From ab3cee3762e5e69f27c302c43691289fdfc12316 Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Mon, 20 Apr 2020 09:24:51 -0700 Subject: blk-mq: In blk_mq_dispatch_rq_list() "no budget" is a reason to kick In blk_mq_dispatch_rq_list(), if blk_mq_sched_needs_restart() returns true and the driver returns BLK_STS_RESOURCE then we'll kick the queue. However, there's another case where we might need to kick it. If we were unable to get budget we can be in much the same state as when the driver returns BLK_STS_RESOURCE, so we should treat it the same. It should be noted that even if we add a whole bunch of extra kicking to the queue in other patches this patch is still important. Specifically any kicking that happened before we re-spliced leftover requests into 'hctx->dispatch' wouldn't have found any work, so we really need to make sure we kick ourselves after we've done the splicing. Signed-off-by: Douglas Anderson Reviewed-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-mq.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index a7785df2c944..1c4bedf500c5 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1206,6 +1206,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, bool no_tag = false; int errors, queued; blk_status_t ret = BLK_STS_OK; + bool no_budget_avail = false; if (list_empty(list)) return false; @@ -1224,6 +1225,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, hctx = rq->mq_hctx; if (!got_budget && !blk_mq_get_dispatch_budget(hctx)) { blk_mq_put_driver_tag(rq); + no_budget_avail = true; break; } @@ -1320,13 +1322,15 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, * * If driver returns BLK_STS_RESOURCE and SCHED_RESTART * bit is set, run queue after a delay to avoid IO stalls - * that could otherwise occur if the queue is idle. + * that could otherwise occur if the queue is idle. We'll do + * similar if we couldn't get budget and SCHED_RESTART is set. */ needs_restart = blk_mq_sched_needs_restart(hctx); if (!needs_restart || (no_tag && list_empty_careful(&hctx->dispatch_wait.entry))) blk_mq_run_hw_queue(hctx, true); - else if (needs_restart && (ret == BLK_STS_RESOURCE)) + else if (needs_restart && (ret == BLK_STS_RESOURCE || + no_budget_avail)) blk_mq_delay_run_hw_queue(hctx, BLK_MQ_RESOURCE_DELAY); blk_mq_update_dispatch_busy(hctx, true); -- cgit v1.2.3 From b9151e7bca82a17ff7aa442a168e0f924a07443c Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Mon, 20 Apr 2020 09:24:52 -0700 Subject: blk-mq: Add blk_mq_delay_run_hw_queues() API call We have: * blk_mq_run_hw_queue() * blk_mq_delay_run_hw_queue() * blk_mq_run_hw_queues() ...but not blk_mq_delay_run_hw_queues(), presumably because nobody needed it before now. Since we need it for a later patch in this series, add it. Signed-off-by: Douglas Anderson Reviewed-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-mq.c | 19 +++++++++++++++++++ include/linux/blk-mq.h | 1 + 2 files changed, 20 insertions(+) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 1c4bedf500c5..cf95e8e0881a 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1545,6 +1545,25 @@ void blk_mq_run_hw_queues(struct request_queue *q, bool async) } EXPORT_SYMBOL(blk_mq_run_hw_queues); +/** + * blk_mq_delay_run_hw_queues - Run all hardware queues asynchronously. + * @q: Pointer to the request queue to run. + * @msecs: Microseconds of delay to wait before running the queues. + */ +void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs) +{ + struct blk_mq_hw_ctx *hctx; + int i; + + queue_for_each_hw_ctx(q, hctx, i) { + if (blk_mq_hctx_stopped(hctx)) + continue; + + blk_mq_delay_run_hw_queue(hctx, msecs); + } +} +EXPORT_SYMBOL(blk_mq_delay_run_hw_queues); + /** * blk_mq_queue_stopped() - check whether one or more hctxs have been stopped * @q: request queue. diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index b45148ba3291..51fbf6f76593 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -508,6 +508,7 @@ void blk_mq_unquiesce_queue(struct request_queue *q); void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs); void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); void blk_mq_run_hw_queues(struct request_queue *q, bool async); +void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs); void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, busy_tag_iter_fn *fn, void *priv); void blk_mq_tagset_wait_completed_request(struct blk_mq_tag_set *tagset); -- cgit v1.2.3 From a0823421a4d7264fc91c7b3769612331493cec1b Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Mon, 20 Apr 2020 09:24:53 -0700 Subject: blk-mq: Rerun dispatching in the case of budget contention If ever a thread running blk-mq code tries to get budget and fails it immediately stops doing work and assumes that whenever budget is freed up that queues will be kicked and whatever work the thread was trying to do will be tried again. One path where budget is freed and queues are kicked in the normal case can be seen in scsi_finish_command(). Specifically: - scsi_finish_command() - scsi_device_unbusy() - # Decrement "device_busy", AKA release budget - scsi_io_completion() - scsi_end_request() - blk_mq_run_hw_queues() The above is all well and good. The problem comes up when a thread claims the budget but then releases it without actually dispatching any work. Since we didn't schedule any work we'll never run the path of finishing work / kicking the queues. This isn't often actually a problem which is why this issue has existed for a while and nobody noticed. Specifically we only get into this situation when we unexpectedly found that we weren't going to do any work. Code that later receives new work kicks the queues. All good, right? The problem shows up, however, if timing is just wrong and we hit a race. To see this race let's think about the case where we only have a budget of 1 (only one thread can hold budget). Now imagine that a thread got budget and then decided not to dispatch work. It's about to call put_budget() but then the thread gets context switched out for a long, long time. While in this state, any and all kicks of the queue (like the when we received new work) will be no-ops because nobody can get budget. Finally the thread holding budget gets to run again and returns. All the normal kicks will have been no-ops and we have an I/O stall. As you can see from the above, you need just the right timing to see the race. To start with, the only case it happens if we thought we had work, actually managed to get the budget, but then actually didn't have work. That's pretty rare to start with. Even then, there's usually a very small amount of time between realizing that there's no work and putting the budget. During this small amount of time new work has to come in and the queue kick has to make it all the way to trying to get the budget and fail. It's pretty unlikely. One case where this could have failed is illustrated by an example of threads running blk_mq_do_dispatch_sched(): * Threads A and B both run has_work() at the same time with the same "hctx". Imagine has_work() is exact. There's no lock, so it's OK if Thread A and B both get back true. * Thread B gets interrupted for a long time right after it decides that there is work. Maybe its CPU gets an interrupt and the interrupt handler is slow. * Thread A runs, get budget, dispatches work. * Thread A's work finishes and budget is released. * Thread B finally runs again and gets budget. * Since Thread A already took care of the work and no new work has come in, Thread B will get NULL from dispatch_request(). I believe this is specifically why dispatch_request() is allowed to return NULL in the first place if has_work() must be exact. * Thread B will now be holding the budget and is about to call put_budget(), but hasn't called it yet. * Thread B gets interrupted for a long time (again). Dang interrupts. * Now Thread C (maybe with a different "hctx" but the same queue) comes along and runs blk_mq_do_dispatch_sched(). * Thread C won't do anything because it can't get budget. * Finally Thread B will run again and put the budget without kicking any queues. Even though the example above is with blk_mq_do_dispatch_sched() I believe the race is possible any time someone is holding budget but doesn't do work. Unfortunately, the unlikely has become more likely if you happen to be using the BFQ I/O scheduler. BFQ, by design, sometimes returns "true" for has_work() but then NULL for dispatch_request() and stays in this state for a while (currently up to 9 ms). Suddenly you only need one race to hit, not two races in a row. With my current setup this is easy to reproduce in reboot tests and traces have actually shown that we hit a race similar to the one described above. Note that we only need to fix blk_mq_do_dispatch_sched() and blk_mq_do_dispatch_ctx() and not the other places that put budget. In other cases we know that we have work to do on at least one "hctx" and code already exists to kick that "hctx"'s queue. When that work finally finishes all the queues will be kicked using the normal flow. One last note is that (at least in the SCSI case) budget is shared by all "hctx"s that have the same queue. Thus we need to make sure to kick the whole queue, not just re-run dispatching on a single "hctx". Signed-off-by: Douglas Anderson Reviewed-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'block') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 74cedea56034..eca81bd4010c 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -80,6 +80,8 @@ void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx) blk_mq_run_hw_queue(hctx, true); } +#define BLK_MQ_BUDGET_DELAY 3 /* ms units */ + /* * Only SCSI implements .get_budget and .put_budget, and SCSI restarts * its queue by itself in its completion handler, so we don't need to @@ -103,6 +105,14 @@ static void blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) rq = e->type->ops.dispatch_request(hctx); if (!rq) { blk_mq_put_dispatch_budget(hctx); + /* + * We're releasing without dispatching. Holding the + * budget could have blocked any "hctx"s with the + * same queue and if we didn't dispatch then there's + * no guarantee anyone will kick the queue. Kick it + * ourselves. + */ + blk_mq_delay_run_hw_queues(q, BLK_MQ_BUDGET_DELAY); break; } @@ -149,6 +159,14 @@ static void blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) rq = blk_mq_dequeue_from_ctx(hctx, ctx); if (!rq) { blk_mq_put_dispatch_budget(hctx); + /* + * We're releasing without dispatching. Holding the + * budget could have blocked any "hctx"s with the + * same queue and if we didn't dispatch then there's + * no guarantee anyone will kick the queue. Kick it + * ourselves. + */ + blk_mq_delay_run_hw_queues(q, BLK_MQ_BUDGET_DELAY); break; } -- cgit v1.2.3 From fa9156ae597c244df4e12891dc8329f649970d9a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:53 +0200 Subject: block: refactor blkpg_ioctl Split each sub-command out into a separate helper, and move those helpers to block/partitions/core.c instead of having a lot of partition manipulation logic open coded in block/ioctl.c. Signed-off-by: Christoph Hellwig --- block/blk.h | 8 ++- block/ioctl.c | 150 +++++++++--------------------------------------- block/partitions/core.c | 115 ++++++++++++++++++++++++++++++++++++- 3 files changed, 145 insertions(+), 128 deletions(-) (limited to 'block') diff --git a/block/blk.h b/block/blk.h index 0a94ec68af32..305e0ac22bf7 100644 --- a/block/blk.h +++ b/block/blk.h @@ -389,11 +389,13 @@ char *disk_name(struct gendisk *hd, int partno, char *buf); #define ADDPART_FLAG_NONE 0 #define ADDPART_FLAG_RAID 1 #define ADDPART_FLAG_WHOLEDISK 2 -struct hd_struct *__must_check add_partition(struct gendisk *disk, int partno, - sector_t start, sector_t len, int flags, - struct partition_meta_info *info); void __delete_partition(struct percpu_ref *ref); void delete_partition(struct gendisk *disk, int partno); +int bdev_add_partition(struct block_device *bdev, int partno, + sector_t start, sector_t length); +int bdev_del_partition(struct block_device *bdev, int partno); +int bdev_resize_partition(struct block_device *bdev, int partno, + sector_t start, sector_t length); int disk_expand_part_tbl(struct gendisk *disk, int target); static inline int hd_ref_init(struct hd_struct *part) diff --git a/block/ioctl.c b/block/ioctl.c index 6e827de1a4c4..75c64811b534 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -16,142 +16,44 @@ static int blkpg_do_ioctl(struct block_device *bdev, struct blkpg_partition __user *upart, int op) { - struct block_device *bdevp; - struct gendisk *disk; - struct hd_struct *part, *lpart; struct blkpg_partition p; - struct disk_part_iter piter; long long start, length; - int partno; if (!capable(CAP_SYS_ADMIN)) return -EACCES; if (copy_from_user(&p, upart, sizeof(struct blkpg_partition))) return -EFAULT; - disk = bdev->bd_disk; if (bdev != bdev->bd_contains) return -EINVAL; - partno = p.pno; - if (partno <= 0) + + if (p.pno <= 0) return -EINVAL; + + if (op == BLKPG_DEL_PARTITION) + return bdev_del_partition(bdev, p.pno); + + start = p.start >> SECTOR_SHIFT; + length = p.length >> SECTOR_SHIFT; + + /* check for fit in a hd_struct */ + if (sizeof(sector_t) < sizeof(long long)) { + long pstart = start, plength = length; + + if (pstart != start || plength != length || pstart < 0 || + plength < 0 || p.pno > 65535) + return -EINVAL; + } + switch (op) { - case BLKPG_ADD_PARTITION: - start = p.start >> 9; - length = p.length >> 9; - /* check for fit in a hd_struct */ - if (sizeof(sector_t) == sizeof(long) && - sizeof(long long) > sizeof(long)) { - long pstart = start, plength = length; - if (pstart != start || plength != length - || pstart < 0 || plength < 0 || partno > 65535) - return -EINVAL; - } - /* check if partition is aligned to blocksize */ - if (p.start & (bdev_logical_block_size(bdev) - 1)) - return -EINVAL; - - mutex_lock(&bdev->bd_mutex); - - /* overlap? */ - disk_part_iter_init(&piter, disk, - DISK_PITER_INCL_EMPTY); - while ((part = disk_part_iter_next(&piter))) { - if (!(start + length <= part->start_sect || - start >= part->start_sect + part->nr_sects)) { - disk_part_iter_exit(&piter); - mutex_unlock(&bdev->bd_mutex); - return -EBUSY; - } - } - disk_part_iter_exit(&piter); - - /* all seems OK */ - part = add_partition(disk, partno, start, length, - ADDPART_FLAG_NONE, NULL); - mutex_unlock(&bdev->bd_mutex); - return PTR_ERR_OR_ZERO(part); - case BLKPG_DEL_PARTITION: - part = disk_get_part(disk, partno); - if (!part) - return -ENXIO; - - bdevp = bdget(part_devt(part)); - disk_put_part(part); - if (!bdevp) - return -ENOMEM; - - mutex_lock(&bdevp->bd_mutex); - if (bdevp->bd_openers) { - mutex_unlock(&bdevp->bd_mutex); - bdput(bdevp); - return -EBUSY; - } - /* all seems OK */ - fsync_bdev(bdevp); - invalidate_bdev(bdevp); - - mutex_lock_nested(&bdev->bd_mutex, 1); - delete_partition(disk, partno); - mutex_unlock(&bdev->bd_mutex); - mutex_unlock(&bdevp->bd_mutex); - bdput(bdevp); - - return 0; - case BLKPG_RESIZE_PARTITION: - start = p.start >> 9; - /* new length of partition in bytes */ - length = p.length >> 9; - /* check for fit in a hd_struct */ - if (sizeof(sector_t) == sizeof(long) && - sizeof(long long) > sizeof(long)) { - long pstart = start, plength = length; - if (pstart != start || plength != length - || pstart < 0 || plength < 0) - return -EINVAL; - } - part = disk_get_part(disk, partno); - if (!part) - return -ENXIO; - bdevp = bdget(part_devt(part)); - if (!bdevp) { - disk_put_part(part); - return -ENOMEM; - } - mutex_lock(&bdevp->bd_mutex); - mutex_lock_nested(&bdev->bd_mutex, 1); - if (start != part->start_sect) { - mutex_unlock(&bdevp->bd_mutex); - mutex_unlock(&bdev->bd_mutex); - bdput(bdevp); - disk_put_part(part); - return -EINVAL; - } - /* overlap? */ - disk_part_iter_init(&piter, disk, - DISK_PITER_INCL_EMPTY); - while ((lpart = disk_part_iter_next(&piter))) { - if (lpart->partno != partno && - !(start + length <= lpart->start_sect || - start >= lpart->start_sect + lpart->nr_sects) - ) { - disk_part_iter_exit(&piter); - mutex_unlock(&bdevp->bd_mutex); - mutex_unlock(&bdev->bd_mutex); - bdput(bdevp); - disk_put_part(part); - return -EBUSY; - } - } - disk_part_iter_exit(&piter); - part_nr_sects_write(part, (sector_t)length); - i_size_write(bdevp->bd_inode, p.length); - mutex_unlock(&bdevp->bd_mutex); - mutex_unlock(&bdev->bd_mutex); - bdput(bdevp); - disk_put_part(part); - return 0; - default: + case BLKPG_ADD_PARTITION: + /* check if partition is aligned to blocksize */ + if (p.start & (bdev_logical_block_size(bdev) - 1)) return -EINVAL; + return bdev_add_partition(bdev, p.pno, start, length); + case BLKPG_RESIZE_PARTITION: + return bdev_resize_partition(bdev, p.pno, start, length); + default: + return -EINVAL; } } diff --git a/block/partitions/core.c b/block/partitions/core.c index bc1ded1331b1..7e2f40875166 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -335,7 +335,7 @@ static DEVICE_ATTR(whole_disk, 0444, whole_disk_show, NULL); * Must be called either with bd_mutex held, before a disk can be opened or * after all disk users are gone. */ -struct hd_struct *add_partition(struct gendisk *disk, int partno, +static struct hd_struct *add_partition(struct gendisk *disk, int partno, sector_t start, sector_t len, int flags, struct partition_meta_info *info) { @@ -472,6 +472,119 @@ out_put: return ERR_PTR(err); } +static bool partition_overlaps(struct gendisk *disk, sector_t start, + sector_t length, int skip_partno) +{ + struct disk_part_iter piter; + struct hd_struct *part; + bool overlap = false; + + disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); + while ((part = disk_part_iter_next(&piter))) { + if (part->partno == skip_partno || + start >= part->start_sect + part->nr_sects || + start + length <= part->start_sect) + continue; + overlap = true; + break; + } + + disk_part_iter_exit(&piter); + return overlap; +} + +int bdev_add_partition(struct block_device *bdev, int partno, + sector_t start, sector_t length) +{ + struct hd_struct *part; + + mutex_lock(&bdev->bd_mutex); + if (partition_overlaps(bdev->bd_disk, start, length, -1)) { + mutex_unlock(&bdev->bd_mutex); + return -EBUSY; + } + + part = add_partition(bdev->bd_disk, partno, start, length, + ADDPART_FLAG_NONE, NULL); + mutex_unlock(&bdev->bd_mutex); + return PTR_ERR_OR_ZERO(part); +} + +int bdev_del_partition(struct block_device *bdev, int partno) +{ + struct block_device *bdevp; + struct hd_struct *part; + int ret = 0; + + part = disk_get_part(bdev->bd_disk, partno); + if (!part) + return -ENXIO; + + bdevp = bdget(part_devt(part)); + disk_put_part(part); + if (!bdevp) + return -ENOMEM; + + mutex_lock(&bdevp->bd_mutex); + + ret = -EBUSY; + if (bdevp->bd_openers) + goto out_unlock; + + fsync_bdev(bdevp); + invalidate_bdev(bdevp); + + mutex_lock_nested(&bdev->bd_mutex, 1); + delete_partition(bdev->bd_disk, partno); + mutex_unlock(&bdev->bd_mutex); + + ret = 0; +out_unlock: + mutex_unlock(&bdevp->bd_mutex); + bdput(bdevp); + return ret; +} + +int bdev_resize_partition(struct block_device *bdev, int partno, + sector_t start, sector_t length) +{ + struct block_device *bdevp; + struct hd_struct *part; + int ret = 0; + + part = disk_get_part(bdev->bd_disk, partno); + if (!part) + return -ENXIO; + + ret = -ENOMEM; + bdevp = bdget(part_devt(part)); + if (!bdevp) + goto out_put_part; + + mutex_lock(&bdevp->bd_mutex); + mutex_lock_nested(&bdev->bd_mutex, 1); + + ret = -EINVAL; + if (start != part->start_sect) + goto out_unlock; + + ret = -EBUSY; + if (partition_overlaps(bdev->bd_disk, start, length, partno)) + goto out_unlock; + + part_nr_sects_write(part, (sector_t)length); + i_size_write(bdevp->bd_inode, length << SECTOR_SHIFT); + + ret = 0; +out_unlock: + mutex_unlock(&bdevp->bd_mutex); + mutex_unlock(&bdev->bd_mutex); + bdput(bdevp); +out_put_part: + disk_put_part(part); + return ret; +} + static bool disk_unlock_native_capacity(struct gendisk *disk) { const struct block_device_operations *bdops = disk->fops; -- cgit v1.2.3 From cddae808aeb77e5c29d22a8e0dfbdaed413f9e04 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:54 +0200 Subject: block: pass a hd_struct to delete_partition All callers have the hd_struct at hand, so pass it instead of performing another lookup. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/blk.h | 2 +- block/genhd.c | 2 +- block/partitions/core.c | 22 ++++++++-------------- 3 files changed, 10 insertions(+), 16 deletions(-) (limited to 'block') diff --git a/block/blk.h b/block/blk.h index 305e0ac22bf7..0cbf64108922 100644 --- a/block/blk.h +++ b/block/blk.h @@ -390,7 +390,7 @@ char *disk_name(struct gendisk *hd, int partno, char *buf); #define ADDPART_FLAG_RAID 1 #define ADDPART_FLAG_WHOLEDISK 2 void __delete_partition(struct percpu_ref *ref); -void delete_partition(struct gendisk *disk, int partno); +void delete_partition(struct gendisk *disk, struct hd_struct *part); int bdev_add_partition(struct block_device *bdev, int partno, sector_t start, sector_t length); int bdev_del_partition(struct block_device *bdev, int partno); diff --git a/block/genhd.c b/block/genhd.c index 06b642b23a07..1cc50ad5b191 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -897,7 +897,7 @@ void del_gendisk(struct gendisk *disk) while ((part = disk_part_iter_next(&piter))) { invalidate_partition(disk, part->partno); bdev_unhash_inode(part_devt(part)); - delete_partition(disk, part->partno); + delete_partition(disk, part); } disk_part_iter_exit(&piter); diff --git a/block/partitions/core.c b/block/partitions/core.c index 7e2f40875166..6dc534b502a9 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -296,20 +296,12 @@ void __delete_partition(struct percpu_ref *ref) * Must be called either with bd_mutex held, before a disk can be opened or * after all disk users are gone. */ -void delete_partition(struct gendisk *disk, int partno) +void delete_partition(struct gendisk *disk, struct hd_struct *part) { struct disk_part_tbl *ptbl = rcu_dereference_protected(disk->part_tbl, 1); - struct hd_struct *part; - - if (partno >= ptbl->len) - return; - part = rcu_dereference_protected(ptbl->part[partno], 1); - if (!part) - return; - - rcu_assign_pointer(ptbl->part[partno], NULL); + rcu_assign_pointer(ptbl->part[part->partno], NULL); rcu_assign_pointer(ptbl->last_lookup, NULL); kobject_put(part->holder_dir); device_del(part_to_dev(part)); @@ -520,10 +512,10 @@ int bdev_del_partition(struct block_device *bdev, int partno) if (!part) return -ENXIO; + ret = -ENOMEM; bdevp = bdget(part_devt(part)); - disk_put_part(part); if (!bdevp) - return -ENOMEM; + goto out_put_part; mutex_lock(&bdevp->bd_mutex); @@ -535,13 +527,15 @@ int bdev_del_partition(struct block_device *bdev, int partno) invalidate_bdev(bdevp); mutex_lock_nested(&bdev->bd_mutex, 1); - delete_partition(bdev->bd_disk, partno); + delete_partition(bdev->bd_disk, part); mutex_unlock(&bdev->bd_mutex); ret = 0; out_unlock: mutex_unlock(&bdevp->bd_mutex); bdput(bdevp); +out_put_part: + disk_put_part(part); return ret; } @@ -617,7 +611,7 @@ int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev) disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); while ((part = disk_part_iter_next(&piter))) - delete_partition(disk, part->partno); + delete_partition(disk, part); disk_part_iter_exit(&piter); return 0; -- cgit v1.2.3 From 8da2892e27833c5ee78788a66941e0e96eedad22 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:55 +0200 Subject: block: cleanup hd_struct freeing Move hd_ref_init out of line as there it isn't anywhere near a fast path, and rename the rcu ref freeing callbacks to be more descriptive. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/blk.h | 10 +--------- block/partitions/core.c | 18 +++++++++++++----- 2 files changed, 14 insertions(+), 14 deletions(-) (limited to 'block') diff --git a/block/blk.h b/block/blk.h index 0cbf64108922..b1a0b8cd87f0 100644 --- a/block/blk.h +++ b/block/blk.h @@ -389,7 +389,6 @@ char *disk_name(struct gendisk *hd, int partno, char *buf); #define ADDPART_FLAG_NONE 0 #define ADDPART_FLAG_RAID 1 #define ADDPART_FLAG_WHOLEDISK 2 -void __delete_partition(struct percpu_ref *ref); void delete_partition(struct gendisk *disk, struct hd_struct *part); int bdev_add_partition(struct block_device *bdev, int partno, sector_t start, sector_t length); @@ -397,14 +396,7 @@ int bdev_del_partition(struct block_device *bdev, int partno); int bdev_resize_partition(struct block_device *bdev, int partno, sector_t start, sector_t length); int disk_expand_part_tbl(struct gendisk *disk, int target); - -static inline int hd_ref_init(struct hd_struct *part) -{ - if (percpu_ref_init(&part->ref, __delete_partition, 0, - GFP_KERNEL)) - return -ENOMEM; - return 0; -} +int hd_ref_init(struct hd_struct *part); static inline void hd_struct_get(struct hd_struct *part) { diff --git a/block/partitions/core.c b/block/partitions/core.c index 6dc534b502a9..c5b47627210a 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -274,10 +274,10 @@ struct device_type part_type = { .uevent = part_uevent, }; -static void delete_partition_work_fn(struct work_struct *work) +static void hd_struct_free_work(struct work_struct *work) { - struct hd_struct *part = container_of(to_rcu_work(work), struct hd_struct, - rcu_work); + struct hd_struct *part = + container_of(to_rcu_work(work), struct hd_struct, rcu_work); part->start_sect = 0; part->nr_sects = 0; @@ -285,13 +285,21 @@ static void delete_partition_work_fn(struct work_struct *work) put_device(part_to_dev(part)); } -void __delete_partition(struct percpu_ref *ref) +static void hd_struct_free(struct percpu_ref *ref) { struct hd_struct *part = container_of(ref, struct hd_struct, ref); - INIT_RCU_WORK(&part->rcu_work, delete_partition_work_fn); + + INIT_RCU_WORK(&part->rcu_work, hd_struct_free_work); queue_rcu_work(system_wq, &part->rcu_work); } +int hd_ref_init(struct hd_struct *part) +{ + if (percpu_ref_init(&part->ref, hd_struct_free, 0, GFP_KERNEL)) + return -ENOMEM; + return 0; +} + /* * Must be called either with bd_mutex held, before a disk can be opened or * after all disk users are gone. -- cgit v1.2.3 From 4377b48da6da44360cc76cd3e0562dbb47dd4904 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:56 +0200 Subject: block: remove hd_struct_kill The function has a single caller, so just open code it. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/blk.h | 5 ----- block/partitions/core.c | 2 +- 2 files changed, 1 insertion(+), 6 deletions(-) (limited to 'block') diff --git a/block/blk.h b/block/blk.h index b1a0b8cd87f0..204963bb03e8 100644 --- a/block/blk.h +++ b/block/blk.h @@ -413,11 +413,6 @@ static inline void hd_struct_put(struct hd_struct *part) percpu_ref_put(&part->ref); } -static inline void hd_struct_kill(struct hd_struct *part) -{ - percpu_ref_kill(&part->ref); -} - static inline void hd_free_part(struct hd_struct *part) { free_part_stats(part); diff --git a/block/partitions/core.c b/block/partitions/core.c index c5b47627210a..7d062599aa33 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -321,7 +321,7 @@ void delete_partition(struct gendisk *disk, struct hd_struct *part) * "in-use" until we really free the gendisk. */ blk_invalidate_devt(part_devt(part)); - hd_struct_kill(part); + percpu_ref_kill(&part->ref); } static ssize_t whole_disk_show(struct device *dev, -- cgit v1.2.3 From d46430bf5a2298f55e20f59a90ebe3545d273b2f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:57 +0200 Subject: block: remove the disk argument from blk_drop_partitions The gendisk can be trivially deducted from the block_device. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/partitions/core.c | 10 +++++----- fs/block_dev.c | 2 +- include/linux/genhd.h | 2 +- 3 files changed, 7 insertions(+), 7 deletions(-) (limited to 'block') diff --git a/block/partitions/core.c b/block/partitions/core.c index 7d062599aa33..deccc3fbcd37 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -603,23 +603,23 @@ static bool disk_unlock_native_capacity(struct gendisk *disk) } } -int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev) +int blk_drop_partitions(struct block_device *bdev) { struct disk_part_iter piter; struct hd_struct *part; int res; - if (!disk_part_scan_enabled(disk)) + if (!disk_part_scan_enabled(bdev->bd_disk)) return 0; if (bdev->bd_part_count || bdev->bd_openers > 1) return -EBUSY; - res = invalidate_partition(disk, 0); + res = invalidate_partition(bdev->bd_disk, 0); if (res) return res; - disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); + disk_part_iter_init(&piter, bdev->bd_disk, DISK_PITER_INCL_EMPTY); while ((part = disk_part_iter_next(&piter))) - delete_partition(disk, part); + delete_partition(bdev->bd_disk, part); disk_part_iter_exit(&piter); return 0; diff --git a/fs/block_dev.c b/fs/block_dev.c index 52b6f646cdbd..9c8de54fa0c9 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -1517,7 +1517,7 @@ int bdev_disk_changed(struct block_device *bdev, bool invalidate) lockdep_assert_held(&bdev->bd_mutex); rescan: - ret = blk_drop_partitions(disk, bdev); + ret = blk_drop_partitions(bdev); if (ret) return ret; diff --git a/include/linux/genhd.h b/include/linux/genhd.h index 9b3fffdf4011..058d895544c7 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -339,7 +339,7 @@ extern dev_t blk_lookup_devt(const char *name, int partno); int bdev_disk_changed(struct block_device *bdev, bool invalidate); int blk_add_partitions(struct gendisk *disk, struct block_device *bdev); -int blk_drop_partitions(struct gendisk *disk, struct block_device *bdev); +int blk_drop_partitions(struct block_device *bdev); extern void printk_all_partitions(void); extern struct gendisk *__alloc_disk_node(int minors, int node_id); -- cgit v1.2.3 From 21be6cdc00954b5e5e5842b69ec8e83fb3cb0816 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:58 +0200 Subject: dasd: use blk_drop_partitions instead of badly reimplementing it Use the blk_drop_partitions function instead of messing around with ioctls that get kernel pointers. For this blk_drop_partitions needs to be exported, which it normally shouldn't - make an exception for s390 only. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/partitions/core.c | 4 ++++ drivers/s390/block/dasd_genhd.c | 20 ++++---------------- 2 files changed, 8 insertions(+), 16 deletions(-) (limited to 'block') diff --git a/block/partitions/core.c b/block/partitions/core.c index deccc3fbcd37..8c5295ca8ea6 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -624,6 +624,10 @@ int blk_drop_partitions(struct block_device *bdev) return 0; } +#ifdef CONFIG_S390 +/* for historic reasons in the DASD driver */ +EXPORT_SYMBOL_GPL(blk_drop_partitions); +#endif static bool blk_add_partition(struct gendisk *disk, struct block_device *bdev, struct parsed_partitions *state, int p) diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c index 7d079154f849..af5b0ecb8f89 100644 --- a/drivers/s390/block/dasd_genhd.c +++ b/drivers/s390/block/dasd_genhd.c @@ -143,9 +143,6 @@ int dasd_scan_partitions(struct dasd_block *block) */ void dasd_destroy_partitions(struct dasd_block *block) { - /* The two structs have 168/176 byte on 31/64 bit. */ - struct blkpg_partition bpart; - struct blkpg_ioctl_arg barg; struct block_device *bdev; /* @@ -155,19 +152,10 @@ void dasd_destroy_partitions(struct dasd_block *block) bdev = block->bdev; block->bdev = NULL; - /* - * See fs/partition/check.c:delete_partition - * Can't call delete_partitions directly. Use ioctl. - * The ioctl also does locking and invalidation. - */ - memset(&bpart, 0, sizeof(struct blkpg_partition)); - memset(&barg, 0, sizeof(struct blkpg_ioctl_arg)); - barg.data = (void __force __user *) &bpart; - barg.op = BLKPG_DEL_PARTITION; - for (bpart.pno = block->gdp->minors - 1; bpart.pno > 0; bpart.pno--) - ioctl_by_bdev(bdev, BLKPG, (unsigned long) &barg); - - invalidate_partition(block->gdp, 0); + mutex_lock(&bdev->bd_mutex); + blk_drop_partitions(bdev); + mutex_unlock(&bdev->bd_mutex); + /* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */ blkdev_put(bdev, FMODE_READ); set_capacity(block->gdp, 0); -- cgit v1.2.3 From e669c1da03a9dde0e7d43852a5b6ade8312e8701 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:28:59 +0200 Subject: block: don't call invalidate_partition from blk_drop_partitions Given that the device must not be busy, most of the calls from invalidate_partition that are related to file system metadata are guranteed to not happen. Just open code the calls to sync_blockdev and invalidate_bdev instead. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/partitions/core.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'block') diff --git a/block/partitions/core.c b/block/partitions/core.c index 8c5295ca8ea6..a94d296d7aed 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -607,15 +607,14 @@ int blk_drop_partitions(struct block_device *bdev) { struct disk_part_iter piter; struct hd_struct *part; - int res; if (!disk_part_scan_enabled(bdev->bd_disk)) return 0; if (bdev->bd_part_count || bdev->bd_openers > 1) return -EBUSY; - res = invalidate_partition(bdev->bd_disk, 0); - if (res) - return res; + + sync_blockdev(bdev); + invalidate_bdev(bdev); disk_part_iter_init(&piter, bdev->bd_disk, DISK_PITER_INCL_EMPTY); while ((part = disk_part_iter_next(&piter))) -- cgit v1.2.3 From d5f3178ec9ab8a3a71763310d260e1d2a047baf1 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:29:00 +0200 Subject: block: simplify block device syncing in bdev_del_partition We just checked a little above that the block device for the partition im busy. That implies no file system is mounted, and thus the only thing in fsync_bdev that actually is used is sync_blockdev. Just call sync_blockdev directly. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/partitions/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/partitions/core.c b/block/partitions/core.c index a94d296d7aed..c085bf85509b 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -531,7 +531,7 @@ int bdev_del_partition(struct block_device *bdev, int partno) if (bdevp->bd_openers) goto out_unlock; - fsync_bdev(bdevp); + sync_blockdev(bdevp); invalidate_bdev(bdevp); mutex_lock_nested(&bdev->bd_mutex, 1); -- cgit v1.2.3 From 02d33b6771fcc63c98cb48cad0cd8b8fb033837a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:29:01 +0200 Subject: block: mark invalidate_partition static invalidate_partition is only used in genhd.c, so mark it static. Also drop the return value given that is is always ignored. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/genhd.c | 27 +++++++++++++-------------- include/linux/fs.h | 1 - 2 files changed, 13 insertions(+), 15 deletions(-) (limited to 'block') diff --git a/block/genhd.c b/block/genhd.c index 1cc50ad5b191..980a4609d4a5 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -878,6 +878,19 @@ void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk) } EXPORT_SYMBOL(device_add_disk_no_queue_reg); +static void invalidate_partition(struct gendisk *disk, int partno) +{ + struct block_device *bdev; + + bdev = bdget_disk(disk, partno); + if (!bdev) + return; + + fsync_bdev(bdev); + __invalidate_device(bdev, true); + bdput(bdev); +} + void del_gendisk(struct gendisk *disk) { struct disk_part_iter piter; @@ -1806,20 +1819,6 @@ int bdev_read_only(struct block_device *bdev) EXPORT_SYMBOL(bdev_read_only); -int invalidate_partition(struct gendisk *disk, int partno) -{ - int res = 0; - struct block_device *bdev = bdget_disk(disk, partno); - if (bdev) { - fsync_bdev(bdev); - res = __invalidate_device(bdev, true); - bdput(bdev); - } - return res; -} - -EXPORT_SYMBOL(invalidate_partition); - /* * Disk events - monitor disk events like media change and eject request. */ diff --git a/include/linux/fs.h b/include/linux/fs.h index 4f6f59b4f22a..2b4e9f86b151 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2723,7 +2723,6 @@ extern bool is_bad_inode(struct inode *); extern int revalidate_disk(struct gendisk *); extern int check_disk_change(struct block_device *); extern int __invalidate_device(struct block_device *, bool); -extern int invalidate_partition(struct gendisk *, int); #endif unsigned long invalidate_mapping_pages(struct address_space *mapping, pgoff_t start, pgoff_t end); -- cgit v1.2.3 From 9bc5c397d8384b50c8202f4400bf2f87fe8291d9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:29:02 +0200 Subject: block: fold bdev_unhash_inode into invalidate_partition invalidate_partition and bdev_unhash_inode are always paired, and invalidate_partition already does an icache lookup for the block device inode. Piggy back on that to remove the inode from the hash. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/genhd.c | 8 ++++++-- fs/block_dev.c | 15 --------------- include/linux/fs.h | 1 - 3 files changed, 6 insertions(+), 18 deletions(-) (limited to 'block') diff --git a/block/genhd.c b/block/genhd.c index 980a4609d4a5..c05d509877fa 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -888,6 +888,12 @@ static void invalidate_partition(struct gendisk *disk, int partno) fsync_bdev(bdev); __invalidate_device(bdev, true); + + /* + * Unhash the bdev inode for this device so that it gets evicted as soon + * as last inode reference is dropped. + */ + remove_inode_hash(bdev->bd_inode); bdput(bdev); } @@ -909,13 +915,11 @@ void del_gendisk(struct gendisk *disk) DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE); while ((part = disk_part_iter_next(&piter))) { invalidate_partition(disk, part->partno); - bdev_unhash_inode(part_devt(part)); delete_partition(disk, part); } disk_part_iter_exit(&piter); invalidate_partition(disk, 0); - bdev_unhash_inode(disk_devt(disk)); set_capacity(disk, 0); disk->flags &= ~GENHD_FL_UP; up_write(&disk->lookup_sem); diff --git a/fs/block_dev.c b/fs/block_dev.c index 9c8de54fa0c9..998820174d3e 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -883,21 +883,6 @@ static int bdev_set(struct inode *inode, void *data) static LIST_HEAD(all_bdevs); -/* - * If there is a bdev inode for this device, unhash it so that it gets evicted - * as soon as last inode reference is dropped. - */ -void bdev_unhash_inode(dev_t dev) -{ - struct inode *inode; - - inode = ilookup5(blockdev_superblock, hash(dev), bdev_test, &dev); - if (inode) { - remove_inode_hash(inode); - iput(inode); - } -} - struct block_device *bdget(dev_t dev) { struct block_device *bdev; diff --git a/include/linux/fs.h b/include/linux/fs.h index 2b4e9f86b151..1a95e5158811 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2581,7 +2581,6 @@ extern struct kmem_cache *names_cachep; #ifdef CONFIG_BLOCK extern int register_blkdev(unsigned int, const char *); extern void unregister_blkdev(unsigned int, const char *); -extern void bdev_unhash_inode(dev_t dev); extern struct block_device *bdget(dev_t); extern struct block_device *bdgrab(struct block_device *bdev); extern void bd_set_size(struct block_device *, loff_t size); -- cgit v1.2.3 From e64a0e16928415648d53d721b3d6fc3635eddf92 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:42:21 +0200 Subject: block: remove RQF_COPY_USER The RQF_COPY_USER is set for bio where the passthrough request mapping helpers decided that bounce buffering is required. It is then used to pad scatterlist for drivers that required it. But given that non-passthrough requests are per definition aligned, and directly mapped pass-through request must be aligned it is not actually required at all. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-map.c | 9 +-------- block/blk-merge.c | 3 +-- block/blk-mq-debugfs.c | 1 - include/linux/blkdev.h | 2 -- 4 files changed, 2 insertions(+), 13 deletions(-) (limited to 'block') diff --git a/block/blk-map.c b/block/blk-map.c index b72c361911a4..b6fa343fea9f 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -654,8 +654,6 @@ int blk_rq_map_user_iov(struct request_queue *q, struct request *rq, bio = rq->bio; } while (iov_iter_count(&i)); - if (!bio_flagged(bio, BIO_USER_MAPPED)) - rq->rq_flags |= RQF_COPY_USER; return 0; unmap_rq: @@ -731,7 +729,6 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, { int reading = rq_data_dir(rq) == READ; unsigned long addr = (unsigned long) kbuf; - int do_copy = 0; struct bio *bio, *orig_bio; int ret; @@ -740,8 +737,7 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, if (!len || !kbuf) return -EINVAL; - do_copy = !blk_rq_aligned(q, addr, len) || object_is_on_stack(kbuf); - if (do_copy) + if (!blk_rq_aligned(q, addr, len) || object_is_on_stack(kbuf)) bio = bio_copy_kern(q, kbuf, len, gfp_mask, reading); else bio = bio_map_kern(q, kbuf, len, gfp_mask); @@ -752,9 +748,6 @@ int blk_rq_map_kern(struct request_queue *q, struct request *rq, void *kbuf, bio->bi_opf &= ~REQ_OP_MASK; bio->bi_opf |= req_op(rq); - if (do_copy) - rq->rq_flags |= RQF_COPY_USER; - orig_bio = bio; ret = blk_rq_append_bio(rq, &bio); if (unlikely(ret)) { diff --git a/block/blk-merge.c b/block/blk-merge.c index 1534ed736363..99c9759f3a8a 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -532,8 +532,7 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, else if (rq->bio) nsegs = __blk_bios_map_sg(q, rq->bio, sglist, &sg); - if (unlikely(rq->rq_flags & RQF_COPY_USER) && - (blk_rq_bytes(rq) & q->dma_pad_mask)) { + if (blk_rq_bytes(rq) && (blk_rq_bytes(rq) & q->dma_pad_mask)) { unsigned int pad_len = (q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1; diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index b3f2ba483992..96b7a35c898a 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -292,7 +292,6 @@ static const char *const rqf_name[] = { RQF_NAME(MQ_INFLIGHT), RQF_NAME(DONTPREP), RQF_NAME(PREEMPT), - RQF_NAME(COPY_USER), RQF_NAME(FAILED), RQF_NAME(QUIET), RQF_NAME(ELVPRIV), diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 32868fbedc9e..76da162b6ae9 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -82,8 +82,6 @@ typedef __u32 __bitwise req_flags_t; /* set for "ide_preempt" requests and also for requests for which the SCSI "quiesce" state must be ignored. */ #define RQF_PREEMPT ((__force req_flags_t)(1 << 8)) -/* contains copies of user pages */ -#define RQF_COPY_USER ((__force req_flags_t)(1 << 9)) /* vaguely specified driver internal error. Ignored by the block layer */ #define RQF_FAILED ((__force req_flags_t)(1 << 10)) /* don't warn about errors */ -- cgit v1.2.3 From 89de1504d53b59b12bfff227328ee3e63dd3a112 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:42:22 +0200 Subject: block: provide a blk_rq_map_sg variant that returns the last element To be able to move some of the special purpose hacks in blk_rq_map_sg into the callers we need a variant that returns the last mapped S/G list element to the caller. Add that variant as __blk_rq_map_sg and make blk_rq_map_sg a trivial inline wrapper around it. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-merge.c | 25 ++++++++++++------------- include/linux/blkdev.h | 10 +++++++++- 2 files changed, 21 insertions(+), 14 deletions(-) (limited to 'block') diff --git a/block/blk-merge.c b/block/blk-merge.c index 99c9759f3a8a..ee618cdb141e 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -519,24 +519,23 @@ static int __blk_bios_map_sg(struct request_queue *q, struct bio *bio, * map a request to scatterlist, return number of sg entries setup. Caller * must make sure sg can hold rq->nr_phys_segments entries */ -int blk_rq_map_sg(struct request_queue *q, struct request *rq, - struct scatterlist *sglist) +int __blk_rq_map_sg(struct request_queue *q, struct request *rq, + struct scatterlist *sglist, struct scatterlist **last_sg) { - struct scatterlist *sg = NULL; int nsegs = 0; if (rq->rq_flags & RQF_SPECIAL_PAYLOAD) - nsegs = __blk_bvec_map_sg(rq->special_vec, sglist, &sg); + nsegs = __blk_bvec_map_sg(rq->special_vec, sglist, last_sg); else if (rq->bio && bio_op(rq->bio) == REQ_OP_WRITE_SAME) - nsegs = __blk_bvec_map_sg(bio_iovec(rq->bio), sglist, &sg); + nsegs = __blk_bvec_map_sg(bio_iovec(rq->bio), sglist, last_sg); else if (rq->bio) - nsegs = __blk_bios_map_sg(q, rq->bio, sglist, &sg); + nsegs = __blk_bios_map_sg(q, rq->bio, sglist, last_sg); if (blk_rq_bytes(rq) && (blk_rq_bytes(rq) & q->dma_pad_mask)) { unsigned int pad_len = (q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1; - sg->length += pad_len; + (*last_sg)->length += pad_len; rq->extra_len += pad_len; } @@ -544,9 +543,9 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, if (op_is_write(req_op(rq))) memset(q->dma_drain_buffer, 0, q->dma_drain_size); - sg_unmark_end(sg); - sg = sg_next(sg); - sg_set_page(sg, virt_to_page(q->dma_drain_buffer), + sg_unmark_end(*last_sg); + *last_sg = sg_next(*last_sg); + sg_set_page(*last_sg, virt_to_page(q->dma_drain_buffer), q->dma_drain_size, ((unsigned long)q->dma_drain_buffer) & (PAGE_SIZE - 1)); @@ -554,8 +553,8 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, rq->extra_len += q->dma_drain_size; } - if (sg) - sg_mark_end(sg); + if (*last_sg) + sg_mark_end(*last_sg); /* * Something must have been wrong if the figured number of @@ -565,7 +564,7 @@ int blk_rq_map_sg(struct request_queue *q, struct request *rq, return nsegs; } -EXPORT_SYMBOL(blk_rq_map_sg); +EXPORT_SYMBOL(__blk_rq_map_sg); static inline int ll_new_hw_segment(struct request *req, struct bio *bio, unsigned int nr_phys_segs) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 76da162b6ae9..496dc9491026 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1136,7 +1136,15 @@ static inline unsigned short blk_rq_nr_discard_segments(struct request *rq) return max_t(unsigned short, rq->nr_phys_segments, 1); } -extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); +int __blk_rq_map_sg(struct request_queue *q, struct request *rq, + struct scatterlist *sglist, struct scatterlist **last_sg); +static inline int blk_rq_map_sg(struct request_queue *q, struct request *rq, + struct scatterlist *sglist) +{ + struct scatterlist *last_sg = NULL; + + return __blk_rq_map_sg(q, rq, sglist, &last_sg); +} extern void blk_dump_rq_flags(struct request *, char *); extern long nr_blockdev_pages(void); -- cgit v1.2.3 From cc97923a5bccc776851c242b61015faf288d5c22 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:42:24 +0200 Subject: block: move dma drain handling to scsi Don't burden the common block code with with specifics of the libata DMA draining mechanism. Instead move most of the code to the scsi midlayer. That also means the nr_phys_segments adjustments in the blk-mq fast path can go away entirely, given that SCSI never looks at nr_phys_segments after mapping the request to a scatterlist. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-merge.c | 14 -------------- block/blk-mq.c | 11 ----------- block/blk-settings.c | 37 ------------------------------------- drivers/ata/libata-scsi.c | 28 ++++++++++------------------ drivers/scsi/scsi_lib.c | 39 ++++++++++++++++++++++++++++++++++----- include/linux/blkdev.h | 7 ------- include/linux/libata.h | 2 ++ include/scsi/scsi_device.h | 3 +++ include/scsi/scsi_host.h | 7 +++++++ 9 files changed, 56 insertions(+), 92 deletions(-) (limited to 'block') diff --git a/block/blk-merge.c b/block/blk-merge.c index ee618cdb141e..25f5a5e00ee6 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -539,20 +539,6 @@ int __blk_rq_map_sg(struct request_queue *q, struct request *rq, rq->extra_len += pad_len; } - if (q->dma_drain_size && q->dma_drain_needed(rq)) { - if (op_is_write(req_op(rq))) - memset(q->dma_drain_buffer, 0, q->dma_drain_size); - - sg_unmark_end(*last_sg); - *last_sg = sg_next(*last_sg); - sg_set_page(*last_sg, virt_to_page(q->dma_drain_buffer), - q->dma_drain_size, - ((unsigned long)q->dma_drain_buffer) & - (PAGE_SIZE - 1)); - nsegs++; - rq->extra_len += q->dma_drain_size; - } - if (*last_sg) sg_mark_end(*last_sg); diff --git a/block/blk-mq.c b/block/blk-mq.c index cf95e8e0881a..2c105cb2a75b 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -667,15 +667,6 @@ void blk_mq_start_request(struct request *rq) blk_add_timer(rq); WRITE_ONCE(rq->state, MQ_RQ_IN_FLIGHT); - if (q->dma_drain_size && blk_rq_bytes(rq)) { - /* - * Make sure space for the drain appears. We know we can do - * this because max_hw_segments has been adjusted to be one - * fewer than the device can handle. - */ - rq->nr_phys_segments++; - } - #ifdef CONFIG_BLK_DEV_INTEGRITY if (blk_integrity_rq(rq) && req_op(rq) == REQ_OP_WRITE) q->integrity.profile->prepare_fn(rq); @@ -695,8 +686,6 @@ static void __blk_mq_requeue_request(struct request *rq) if (blk_mq_request_started(rq)) { WRITE_ONCE(rq->state, MQ_RQ_IDLE); rq->rq_flags &= ~RQF_TIMED_OUT; - if (q->dma_drain_size && blk_rq_bytes(rq)) - rq->nr_phys_segments--; } } diff --git a/block/blk-settings.c b/block/blk-settings.c index 14397b4c4b53..2ab1967b9716 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -651,43 +651,6 @@ void blk_queue_update_dma_pad(struct request_queue *q, unsigned int mask) } EXPORT_SYMBOL(blk_queue_update_dma_pad); -/** - * blk_queue_dma_drain - Set up a drain buffer for excess dma. - * @q: the request queue for the device - * @dma_drain_needed: fn which returns non-zero if drain is necessary - * @buf: physically contiguous buffer - * @size: size of the buffer in bytes - * - * Some devices have excess DMA problems and can't simply discard (or - * zero fill) the unwanted piece of the transfer. They have to have a - * real area of memory to transfer it into. The use case for this is - * ATAPI devices in DMA mode. If the packet command causes a transfer - * bigger than the transfer size some HBAs will lock up if there - * aren't DMA elements to contain the excess transfer. What this API - * does is adjust the queue so that the buf is always appended - * silently to the scatterlist. - * - * Note: This routine adjusts max_hw_segments to make room for appending - * the drain buffer. If you call blk_queue_max_segments() after calling - * this routine, you must set the limit to one fewer than your device - * can support otherwise there won't be room for the drain buffer. - */ -int blk_queue_dma_drain(struct request_queue *q, - dma_drain_needed_fn *dma_drain_needed, - void *buf, unsigned int size) -{ - if (queue_max_segments(q) < 2) - return -EINVAL; - /* make room for appending the drain */ - blk_queue_max_segments(q, queue_max_segments(q) - 1); - q->dma_drain_needed = dma_drain_needed; - q->dma_drain_buffer = buf; - q->dma_drain_size = size; - - return 0; -} -EXPORT_SYMBOL_GPL(blk_queue_dma_drain); - /** * blk_queue_segment_boundary - set boundary rules for segment merging * @q: the request queue for the device diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 36e588d88b95..feb13b8f93d7 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -1017,16 +1017,11 @@ void ata_scsi_sdev_config(struct scsi_device *sdev) * RETURNS: * 1 if ; otherwise, 0. */ -static int atapi_drain_needed(struct request *rq) +bool ata_scsi_dma_need_drain(struct request *rq) { - if (likely(!blk_rq_is_passthrough(rq))) - return 0; - - if (!blk_rq_bytes(rq) || op_is_write(req_op(rq))) - return 0; - return atapi_cmd_type(scsi_req(rq)->cmd[0]) == ATAPI_MISC; } +EXPORT_SYMBOL_GPL(ata_scsi_dma_need_drain); int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev) { @@ -1039,21 +1034,21 @@ int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev) blk_queue_max_hw_sectors(q, dev->max_sectors); if (dev->class == ATA_DEV_ATAPI) { - void *buf; - sdev->sector_size = ATA_SECT_SIZE; /* set DMA padding */ blk_queue_update_dma_pad(q, ATA_DMA_PAD_SZ - 1); - /* configure draining */ - buf = kmalloc(ATAPI_MAX_DRAIN, q->bounce_gfp | GFP_KERNEL); - if (!buf) { + /* make room for appending the drain */ + blk_queue_max_segments(q, queue_max_segments(q) - 1); + + sdev->dma_drain_len = ATAPI_MAX_DRAIN; + sdev->dma_drain_buf = kmalloc(sdev->dma_drain_len, + q->bounce_gfp | GFP_KERNEL); + if (!sdev->dma_drain_buf) { ata_dev_err(dev, "drain buffer allocation failed\n"); return -ENOMEM; } - - blk_queue_dma_drain(q, atapi_drain_needed, buf, ATAPI_MAX_DRAIN); } else { sdev->sector_size = ata_id_logical_sector_size(dev->id); sdev->manage_start_stop = 1; @@ -1135,7 +1130,6 @@ EXPORT_SYMBOL_GPL(ata_scsi_slave_config); void ata_scsi_slave_destroy(struct scsi_device *sdev) { struct ata_port *ap = ata_shost_to_port(sdev->host); - struct request_queue *q = sdev->request_queue; unsigned long flags; struct ata_device *dev; @@ -1152,9 +1146,7 @@ void ata_scsi_slave_destroy(struct scsi_device *sdev) } spin_unlock_irqrestore(ap->lock, flags); - kfree(q->dma_drain_buffer); - q->dma_drain_buffer = NULL; - q->dma_drain_size = 0; + kfree(sdev->dma_drain_buf); } EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy); diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 4e42acbb3f32..88cac92fc153 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -978,6 +978,14 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) scsi_io_completion_action(cmd, result); } +static inline bool scsi_cmd_needs_dma_drain(struct scsi_device *sdev, + struct request *rq) +{ + return sdev->dma_drain_len && blk_rq_is_passthrough(rq) && + !op_is_write(req_op(rq)) && + sdev->host->hostt->dma_need_drain(rq); +} + /* * Function: scsi_init_io() * @@ -991,26 +999,47 @@ void scsi_io_completion(struct scsi_cmnd *cmd, unsigned int good_bytes) */ blk_status_t scsi_init_io(struct scsi_cmnd *cmd) { + struct scsi_device *sdev = cmd->device; struct request *rq = cmd->request; + unsigned short nr_segs = blk_rq_nr_phys_segments(rq); + struct scatterlist *last_sg = NULL; blk_status_t ret; + bool need_drain = scsi_cmd_needs_dma_drain(sdev, rq); int count; - if (WARN_ON_ONCE(!blk_rq_nr_phys_segments(rq))) + if (WARN_ON_ONCE(!nr_segs)) return BLK_STS_IOERR; + /* + * Make sure there is space for the drain. The driver must adjust + * max_hw_segments to be prepared for this. + */ + if (need_drain) + nr_segs++; + /* * If sg table allocation fails, requeue request later. */ - if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, - blk_rq_nr_phys_segments(rq), cmd->sdb.table.sgl, - SCSI_INLINE_SG_CNT))) + if (unlikely(sg_alloc_table_chained(&cmd->sdb.table, nr_segs, + cmd->sdb.table.sgl, SCSI_INLINE_SG_CNT))) return BLK_STS_RESOURCE; /* * Next, walk the list, and fill in the addresses and sizes of * each segment. */ - count = blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl); + count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg); + + if (need_drain) { + sg_unmark_end(last_sg); + last_sg = sg_next(last_sg); + sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len); + sg_mark_end(last_sg); + + rq->extra_len += sdev->dma_drain_len; + count++; + } + BUG_ON(count > cmd->sdb.table.nents); cmd->sdb.table.nents = count; cmd->sdb.length = blk_rq_payload_bytes(rq); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 496dc9491026..8e4726bce498 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -288,7 +288,6 @@ struct blk_queue_ctx; typedef blk_qc_t (make_request_fn) (struct request_queue *q, struct bio *bio); struct bio_vec; -typedef int (dma_drain_needed_fn)(struct request *); enum blk_eh_timer_return { BLK_EH_DONE, /* drivers has completed the command */ @@ -397,7 +396,6 @@ struct request_queue { struct rq_qos *rq_qos; make_request_fn *make_request_fn; - dma_drain_needed_fn *dma_drain_needed; const struct blk_mq_ops *mq_ops; @@ -467,8 +465,6 @@ struct request_queue { */ unsigned long nr_requests; /* Max # of requests */ - unsigned int dma_drain_size; - void *dma_drain_buffer; unsigned int dma_pad_mask; unsigned int dma_alignment; @@ -1097,9 +1093,6 @@ extern void disk_stack_limits(struct gendisk *disk, struct block_device *bdev, sector_t offset); extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int); -extern int blk_queue_dma_drain(struct request_queue *q, - dma_drain_needed_fn *dma_drain_needed, - void *buf, unsigned int size); extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); extern void blk_queue_virt_boundary(struct request_queue *, unsigned long); extern void blk_queue_dma_alignment(struct request_queue *, int); diff --git a/include/linux/libata.h b/include/linux/libata.h index cffa4714bfa8..af832852e620 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -1092,6 +1092,7 @@ extern int ata_scsi_ioctl(struct scsi_device *dev, unsigned int cmd, #define ATA_SCSI_COMPAT_IOCTL /* empty */ #endif extern int ata_scsi_queuecmd(struct Scsi_Host *h, struct scsi_cmnd *cmd); +bool ata_scsi_dma_need_drain(struct request *rq); extern int ata_sas_scsi_ioctl(struct ata_port *ap, struct scsi_device *dev, unsigned int cmd, void __user *arg); extern bool ata_link_online(struct ata_link *link); @@ -1387,6 +1388,7 @@ extern struct device_attribute *ata_common_sdev_attrs[]; .ioctl = ata_scsi_ioctl, \ ATA_SCSI_COMPAT_IOCTL \ .queuecommand = ata_scsi_queuecmd, \ + .dma_need_drain = ata_scsi_dma_need_drain, \ .can_queue = ATA_DEF_QUEUE, \ .tag_alloc_policy = BLK_TAG_ALLOC_RR, \ .this_id = ATA_SHT_THIS_ID, \ diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index c3cba2aaf934..bc5909033d13 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -229,6 +229,9 @@ struct scsi_device { struct scsi_device_handler *handler; void *handler_data; + size_t dma_drain_len; + void *dma_drain_buf; + unsigned char access_state; struct mutex state_mutex; enum scsi_device_state sdev_state; diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 822e8cda8d9b..46ef8cccc982 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -270,6 +270,13 @@ struct scsi_host_template { */ int (* map_queues)(struct Scsi_Host *shost); + /* + * Check if scatterlists need to be padded for DMA draining. + * + * Status: OPTIONAL + */ + bool (* dma_need_drain)(struct request *rq); + /* * This function determines the BIOS parameters for a given * harddisk. These tend to be numbers that are made up by -- cgit v1.2.3 From bdf8710d69f82ee6fd41b0166300c3306898b3c1 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 14 Apr 2020 09:42:25 +0200 Subject: block: move dma_pad handling from blk_rq_map_sg into the callers There are only two callers of blk_rq_map_sg/__blk_rq_map_sg that set the dma_pad value in the queue. Move the handling into those callers instead of burdening the common code, and move the ->extra_len field from struct request to struct scsi_cmnd. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 1 - block/blk-merge.c | 8 -------- block/blk-mq.c | 1 - drivers/ata/libata-scsi.c | 2 +- drivers/ide/ide-io.c | 7 +++++-- drivers/scsi/scsi_lib.c | 10 +++++++++- include/linux/blkdev.h | 2 -- include/scsi/scsi_cmnd.h | 1 + 8 files changed, 16 insertions(+), 16 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 7e4a1da0715e..311596d5dbc4 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1638,7 +1638,6 @@ int blk_rq_prep_clone(struct request *rq, struct request *rq_src, } rq->nr_phys_segments = rq_src->nr_phys_segments; rq->ioprio = rq_src->ioprio; - rq->extra_len = rq_src->extra_len; return 0; diff --git a/block/blk-merge.c b/block/blk-merge.c index 25f5a5e00ee6..c49eb3bdd0be 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -531,14 +531,6 @@ int __blk_rq_map_sg(struct request_queue *q, struct request *rq, else if (rq->bio) nsegs = __blk_bios_map_sg(q, rq->bio, sglist, last_sg); - if (blk_rq_bytes(rq) && (blk_rq_bytes(rq) & q->dma_pad_mask)) { - unsigned int pad_len = - (q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1; - - (*last_sg)->length += pad_len; - rq->extra_len += pad_len; - } - if (*last_sg) sg_mark_end(*last_sg); diff --git a/block/blk-mq.c b/block/blk-mq.c index 2c105cb2a75b..71d0894ce1c5 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -318,7 +318,6 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, rq->nr_integrity_segments = 0; #endif /* tag was already set */ - rq->extra_len = 0; WRITE_ONCE(rq->deadline, 0); rq->timeout = 0; diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index feb13b8f93d7..435781a16875 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -649,7 +649,7 @@ static void ata_qc_set_pc_nbytes(struct ata_queued_cmd *qc) { struct scsi_cmnd *scmd = qc->scsicmd; - qc->extrabytes = scmd->request->extra_len; + qc->extrabytes = scmd->extra_len; qc->nbytes = scsi_bufflen(scmd) + qc->extrabytes; } diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c index b137f27a34d5..c31f1d2b3b07 100644 --- a/drivers/ide/ide-io.c +++ b/drivers/ide/ide-io.c @@ -233,10 +233,13 @@ static ide_startstop_t do_special(ide_drive_t *drive) void ide_map_sg(ide_drive_t *drive, struct ide_cmd *cmd) { ide_hwif_t *hwif = drive->hwif; - struct scatterlist *sg = hwif->sg_table; + struct scatterlist *sg = hwif->sg_table, *last_sg = NULL; struct request *rq = cmd->rq; - cmd->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); + cmd->sg_nents = __blk_rq_map_sg(drive->queue, rq, sg, &last_sg); + if (blk_rq_bytes(rq) && (blk_rq_bytes(rq) & rq->q->dma_pad_mask)) + last_sg->length += + (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1; } EXPORT_SYMBOL_GPL(ide_map_sg); diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 88cac92fc153..0a73230a8f16 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1030,13 +1030,21 @@ blk_status_t scsi_init_io(struct scsi_cmnd *cmd) */ count = __blk_rq_map_sg(rq->q, rq, cmd->sdb.table.sgl, &last_sg); + if (blk_rq_bytes(rq) & rq->q->dma_pad_mask) { + unsigned int pad_len = + (rq->q->dma_pad_mask & ~blk_rq_bytes(rq)) + 1; + + last_sg->length += pad_len; + cmd->extra_len += pad_len; + } + if (need_drain) { sg_unmark_end(last_sg); last_sg = sg_next(last_sg); sg_set_buf(last_sg, sdev->dma_drain_buf, sdev->dma_drain_len); sg_mark_end(last_sg); - rq->extra_len += sdev->dma_drain_len; + cmd->extra_len += sdev->dma_drain_len; count++; } diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 8e4726bce498..f00bd4042295 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -224,8 +224,6 @@ struct request { unsigned short write_hint; unsigned short ioprio; - unsigned int extra_len; /* length of alignment and padding */ - enum mq_rq_state state; refcount_t ref; diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 80ac89e47b47..f93c0b800790 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -142,6 +142,7 @@ struct scsi_cmnd { unsigned long state; /* Command completion state */ unsigned char tag; /* SCSI-II queued command tag */ + unsigned int extra_len; /* length of alignment and padding */ }; /* -- cgit v1.2.3 From 28d65729b050977d8a9125e6726871e83bd22124 Mon Sep 17 00:00:00 2001 From: Salman Qazi Date: Fri, 24 Apr 2020 08:03:21 -0700 Subject: block: Limit number of items taken from the I/O scheduler in one go Flushes bypass the I/O scheduler and get added to hctx->dispatch in blk_mq_sched_bypass_insert. This can happen while a kworker is running hctx->run_work work item and is past the point in blk_mq_sched_dispatch_requests where hctx->dispatch is checked. The blk_mq_do_dispatch_sched call is not guaranteed to end in bounded time, because the I/O scheduler can feed an arbitrary number of commands. Since we have only one hctx->run_work, the commands waiting in hctx->dispatch will wait an arbitrary length of time for run_work to be rerun. A similar phenomenon exists with dispatches from the software queue. The solution is to poll hctx->dispatch in blk_mq_do_dispatch_sched and blk_mq_do_dispatch_ctx and return from the run_work handler and let it rerun. Signed-off-by: Salman Qazi Reviewed-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 64 +++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 51 insertions(+), 13 deletions(-) (limited to 'block') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index eca81bd4010c..702ce525933c 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -86,12 +86,16 @@ void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx) * Only SCSI implements .get_budget and .put_budget, and SCSI restarts * its queue by itself in its completion handler, so we don't need to * restart queue if .get_budget() returns BLK_STS_NO_RESOURCE. + * + * Returns -EAGAIN if hctx->dispatch was found non-empty and run_work has to + * be run again. This is necessary to avoid starving flushes. */ -static void blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) +static int blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; struct elevator_queue *e = q->elevator; LIST_HEAD(rq_list); + int ret = 0; do { struct request *rq; @@ -99,6 +103,11 @@ static void blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) if (e->type->ops.has_work && !e->type->ops.has_work(hctx)) break; + if (!list_empty_careful(&hctx->dispatch)) { + ret = -EAGAIN; + break; + } + if (!blk_mq_get_dispatch_budget(hctx)) break; @@ -123,6 +132,8 @@ static void blk_mq_do_dispatch_sched(struct blk_mq_hw_ctx *hctx) */ list_add(&rq->queuelist, &rq_list); } while (blk_mq_dispatch_rq_list(q, &rq_list, true)); + + return ret; } static struct blk_mq_ctx *blk_mq_next_ctx(struct blk_mq_hw_ctx *hctx, @@ -140,16 +151,25 @@ static struct blk_mq_ctx *blk_mq_next_ctx(struct blk_mq_hw_ctx *hctx, * Only SCSI implements .get_budget and .put_budget, and SCSI restarts * its queue by itself in its completion handler, so we don't need to * restart queue if .get_budget() returns BLK_STS_NO_RESOURCE. + * + * Returns -EAGAIN if hctx->dispatch was found non-empty and run_work has to + * to be run again. This is necessary to avoid starving flushes. */ -static void blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) +static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; LIST_HEAD(rq_list); struct blk_mq_ctx *ctx = READ_ONCE(hctx->dispatch_from); + int ret = 0; do { struct request *rq; + if (!list_empty_careful(&hctx->dispatch)) { + ret = -EAGAIN; + break; + } + if (!sbitmap_any_bit_set(&hctx->ctx_map)) break; @@ -183,21 +203,17 @@ static void blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) } while (blk_mq_dispatch_rq_list(q, &rq_list, true)); WRITE_ONCE(hctx->dispatch_from, ctx); + return ret; } -void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) +int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; struct elevator_queue *e = q->elevator; const bool has_sched_dispatch = e && e->type->ops.dispatch_request; + int ret = 0; LIST_HEAD(rq_list); - /* RCU or SRCU read lock is needed before checking quiesced flag */ - if (unlikely(blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q))) - return; - - hctx->run++; - /* * If we have previous entries on our dispatch list, grab them first for * more fair dispatch. @@ -226,19 +242,41 @@ void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) blk_mq_sched_mark_restart_hctx(hctx); if (blk_mq_dispatch_rq_list(q, &rq_list, false)) { if (has_sched_dispatch) - blk_mq_do_dispatch_sched(hctx); + ret = blk_mq_do_dispatch_sched(hctx); else - blk_mq_do_dispatch_ctx(hctx); + ret = blk_mq_do_dispatch_ctx(hctx); } } else if (has_sched_dispatch) { - blk_mq_do_dispatch_sched(hctx); + ret = blk_mq_do_dispatch_sched(hctx); } else if (hctx->dispatch_busy) { /* dequeue request one by one from sw queue if queue is busy */ - blk_mq_do_dispatch_ctx(hctx); + ret = blk_mq_do_dispatch_ctx(hctx); } else { blk_mq_flush_busy_ctxs(hctx, &rq_list); blk_mq_dispatch_rq_list(q, &rq_list, false); } + + return ret; +} + +void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) +{ + struct request_queue *q = hctx->queue; + + /* RCU or SRCU read lock is needed before checking quiesced flag */ + if (unlikely(blk_mq_hctx_stopped(hctx) || blk_queue_quiesced(q))) + return; + + hctx->run++; + + /* + * A return of -EAGAIN is an indication that hctx->dispatch is not + * empty and we must run again in order to avoid starving flushes. + */ + if (__blk_mq_sched_dispatch_requests(hctx) == -EAGAIN) { + if (__blk_mq_sched_dispatch_requests(hctx) == -EAGAIN) + blk_mq_run_hw_queue(hctx, true); + } } bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio, -- cgit v1.2.3 From 3e82c3485e835b4dc7374316357fa388676201d7 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 25 Apr 2020 09:55:51 +0200 Subject: block: remove create_io_context create_io_context just has a single caller, which also happens to not even use the return value. Just open code it there. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 11 ++++++----- block/blk.h | 20 -------------------- 2 files changed, 6 insertions(+), 25 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 311596d5dbc4..38e984d95e84 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -963,12 +963,13 @@ generic_make_request_checks(struct bio *bio) } /* - * Various block parts want %current->io_context and lazy ioc - * allocation ends up trading a lot of pain for a small amount of - * memory. Just allocate it upfront. This may fail and block - * layer knows how to live with it. + * Various block parts want %current->io_context, so allocate it up + * front rather than dealing with lots of pain to allocate it only + * where needed. This may fail and the block layer knows how to live + * with it. */ - create_io_context(GFP_ATOMIC, q->node); + if (unlikely(!current->io_context)) + create_task_io_context(current, GFP_ATOMIC, q->node); if (!blkcg_bio_issue_check(q, bio)) return false; diff --git a/block/blk.h b/block/blk.h index 204963bb03e8..73bd3b1c6938 100644 --- a/block/blk.h +++ b/block/blk.h @@ -303,26 +303,6 @@ void ioc_clear_queue(struct request_queue *q); int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node); -/** - * create_io_context - try to create task->io_context - * @gfp_mask: allocation mask - * @node: allocation node - * - * If %current->io_context is %NULL, allocate a new io_context and install - * it. Returns the current %current->io_context which may be %NULL if - * allocation failed. - * - * Note that this function can't be called with IRQ disabled because - * task_lock which protects %current->io_context is IRQ-unsafe. - */ -static inline struct io_context *create_io_context(gfp_t gfp_mask, int node) -{ - WARN_ON_ONCE(irqs_disabled()); - if (unlikely(!current->io_context)) - create_task_io_context(current, gfp_mask, node); - return current->io_context; -} - /* * Internal throttling interface */ -- cgit v1.2.3 From 8cf7961dab42c9177a556b719c15f5b9449c24d1 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 25 Apr 2020 09:53:36 +0200 Subject: block: bypass ->make_request_fn for blk-mq drivers Call blk_mq_make_request when no ->make_request_fn is set. This is safe now that blk_alloc_queue always sets up the pointer for make_request based drivers. This avoids an indirect call in the blk-mq driver I/O fast path, which is rather expensive due to spectre mitigations. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 26 +++++++++++++++++--------- block/blk-mq.c | 4 ++-- drivers/md/dm.c | 3 +++ include/linux/blk-mq.h | 2 ++ 4 files changed, 24 insertions(+), 11 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 38e984d95e84..dffff2100888 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1073,7 +1073,10 @@ blk_qc_t generic_make_request(struct bio *bio) /* Create a fresh bio_list for all subordinate requests */ bio_list_on_stack[1] = bio_list_on_stack[0]; bio_list_init(&bio_list_on_stack[0]); - ret = q->make_request_fn(q, bio); + if (q->make_request_fn) + ret = q->make_request_fn(q, bio); + else + ret = blk_mq_make_request(q, bio); blk_queue_exit(q); @@ -1113,9 +1116,7 @@ EXPORT_SYMBOL(generic_make_request); * * This function behaves like generic_make_request(), but does not protect * against recursion. Must only be used if the called driver is known - * to not call generic_make_request (or direct_make_request) again from - * its make_request function. (Calling direct_make_request again from - * a workqueue is perfectly fine as that doesn't recurse). + * to be blk-mq based. */ blk_qc_t direct_make_request(struct bio *bio) { @@ -1123,20 +1124,27 @@ blk_qc_t direct_make_request(struct bio *bio) bool nowait = bio->bi_opf & REQ_NOWAIT; blk_qc_t ret; + if (WARN_ON_ONCE(q->make_request_fn)) + goto io_error; if (!generic_make_request_checks(bio)) return BLK_QC_T_NONE; if (unlikely(blk_queue_enter(q, nowait ? BLK_MQ_REQ_NOWAIT : 0))) { if (nowait && !blk_queue_dying(q)) - bio_wouldblock_error(bio); - else - bio_io_error(bio); - return BLK_QC_T_NONE; + goto would_block; + goto io_error; } - ret = q->make_request_fn(q, bio); + ret = blk_mq_make_request(q, bio); blk_queue_exit(q); return ret; + +would_block: + bio_wouldblock_error(bio); + return BLK_QC_T_NONE; +io_error: + bio_io_error(bio); + return BLK_QC_T_NONE; } EXPORT_SYMBOL_GPL(direct_make_request); diff --git a/block/blk-mq.c b/block/blk-mq.c index 71d0894ce1c5..bcc3a2397d4a 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1984,7 +1984,7 @@ static void blk_add_rq_to_plug(struct blk_plug *plug, struct request *rq) * * Returns: Request queue cookie. */ -static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) +blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) { const int is_sync = op_is_sync(bio->bi_opf); const int is_flush_fua = op_is_flush(bio->bi_opf); @@ -2096,6 +2096,7 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) return cookie; } +EXPORT_SYMBOL_GPL(blk_mq_make_request); /* only for request based dm */ void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, unsigned int hctx_idx) @@ -2955,7 +2956,6 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, INIT_LIST_HEAD(&q->requeue_list); spin_lock_init(&q->requeue_lock); - q->make_request_fn = blk_mq_make_request; q->nr_requests = set->queue_depth; /* diff --git a/drivers/md/dm.c b/drivers/md/dm.c index db9e46114653..0eb93da44ea2 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1788,6 +1788,9 @@ static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio) int srcu_idx; struct dm_table *map; + if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) + return blk_mq_make_request(q, bio); + map = dm_get_live_table(md, &srcu_idx); /* if we're suspended, we have to queue this io for later */ diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 51fbf6f76593..d7307795439a 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -578,4 +578,6 @@ static inline void blk_mq_cleanup_rq(struct request *rq) rq->q->mq_ops->cleanup_rq(rq); } +blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio); + #endif -- cgit v1.2.3 From e1b586f2b83d56f40faa5f23d5ecac866d61320d Mon Sep 17 00:00:00 2001 From: Zheng Bin Date: Wed, 29 Apr 2020 09:36:32 +0800 Subject: blk-mq: make function '__blk_mq_sched_dispatch_requests' static Fix sparse warnings: block/blk-mq-sched.c:209:5: warning: symbol '__blk_mq_sched_dispatch_requests' was not declared. Should it be static? Reported-by: Hulk Robot Signed-off-by: Zheng Bin Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-mq-sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c index 702ce525933c..fdcc2c1dd178 100644 --- a/block/blk-mq-sched.c +++ b/block/blk-mq-sched.c @@ -206,7 +206,7 @@ static int blk_mq_do_dispatch_ctx(struct blk_mq_hw_ctx *hctx) return ret; } -int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) +static int __blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx) { struct request_queue *q = hctx->queue; struct elevator_queue *e = q->elevator; -- cgit v1.2.3 From 3fdd40861d800a4e1eb67c5158e8ab90076e2f93 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 28 Apr 2020 13:27:53 +0200 Subject: block: improve the submit_bio and generic_make_request documentation The current documentation is a little weird, as it doesn't clearly explain which function to use, and also has the guts of the information on generic_make_request, which is the internal interface for stacking drivers. Fix this up by properly documenting submit_bio, and only documenting the differences and the use case for generic_make_request. Signed-off-by: Christoph Hellwig Reviewed-by: Keith Busch Signed-off-by: Jens Axboe --- block/blk-core.c | 35 ++++++++++++----------------------- 1 file changed, 12 insertions(+), 23 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index dffff2100888..68351ee94ad2 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -992,28 +992,13 @@ end_io: } /** - * generic_make_request - hand a buffer to its device driver for I/O + * generic_make_request - re-submit a bio to the block device layer for I/O * @bio: The bio describing the location in memory and on the device. * - * generic_make_request() is used to make I/O requests of block - * devices. It is passed a &struct bio, which describes the I/O that needs - * to be done. - * - * generic_make_request() does not return any status. The - * success/failure status of the request, along with notification of - * completion, is delivered asynchronously through the bio->bi_end_io - * function described (one day) else where. - * - * The caller of generic_make_request must make sure that bi_io_vec - * are set to describe the memory buffer, and that bi_dev and bi_sector are - * set to describe the device address, and the - * bi_end_io and optionally bi_private are set to describe how - * completion notification should be signaled. - * - * generic_make_request and the drivers it calls may use bi_next if this - * bio happens to be merged with someone else, and may resubmit the bio to - * a lower device by calling into generic_make_request recursively, which - * means the bio should NOT be touched after the call to ->make_request_fn. + * This is a version of submit_bio() that shall only be used for I/O that is + * resubmitted to lower level drivers by stacking block drivers. All file + * systems and other upper level users of the block layer should use + * submit_bio() instead. */ blk_qc_t generic_make_request(struct bio *bio) { @@ -1152,10 +1137,14 @@ EXPORT_SYMBOL_GPL(direct_make_request); * submit_bio - submit a bio to the block device layer for I/O * @bio: The &struct bio which describes the I/O * - * submit_bio() is very similar in purpose to generic_make_request(), and - * uses that function to do most of the work. Both are fairly rough - * interfaces; @bio must be presetup and ready for I/O. + * submit_bio() is used to submit I/O requests to block devices. It is passed a + * fully set up &struct bio that describes the I/O that needs to be done. The + * bio will be send to the device described by the bi_disk and bi_partno fields. * + * The success/failure status of the request, along with notification of + * completion, is delivered asynchronously through the ->bi_end_io() callback + * in @bio. The bio must NOT be touched by thecaller until ->bi_end_io() has + * been called. */ blk_qc_t submit_bio(struct bio *bio) { -- cgit v1.2.3 From 760f83ea63a7b2c12b3b1e656b24cbb880b6b814 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 28 Apr 2020 13:27:54 +0200 Subject: block: cleanup the memory stall accounting in submit_bio Instead of a convoluted chain just check for REQ_OP_READ directly, and keep all the memory stall code together in a single unlikely branch. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Weiner Signed-off-by: Jens Axboe --- block/blk-core.c | 30 ++++++++++++++---------------- 1 file changed, 14 insertions(+), 16 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 68351ee94ad2..81a291085c6c 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1148,10 +1148,6 @@ EXPORT_SYMBOL_GPL(direct_make_request); */ blk_qc_t submit_bio(struct bio *bio) { - bool workingset_read = false; - unsigned long pflags; - blk_qc_t ret; - if (blkcg_punt_bio_submit(bio)) return BLK_QC_T_NONE; @@ -1170,8 +1166,6 @@ blk_qc_t submit_bio(struct bio *bio) if (op_is_write(bio_op(bio))) { count_vm_events(PGPGOUT, count); } else { - if (bio_flagged(bio, BIO_WORKINGSET)) - workingset_read = true; task_io_account_read(bio->bi_iter.bi_size); count_vm_events(PGPGIN, count); } @@ -1187,20 +1181,24 @@ blk_qc_t submit_bio(struct bio *bio) } /* - * If we're reading data that is part of the userspace - * workingset, count submission time as memory stall. When the - * device is congested, or the submitting cgroup IO-throttled, - * submission can be a significant part of overall IO time. + * If we're reading data that is part of the userspace workingset, count + * submission time as memory stall. When the device is congested, or + * the submitting cgroup IO-throttled, submission can be a significant + * part of overall IO time. */ - if (workingset_read) - psi_memstall_enter(&pflags); - - ret = generic_make_request(bio); + if (unlikely(bio_op(bio) == REQ_OP_READ && + bio_flagged(bio, BIO_WORKINGSET))) { + unsigned long pflags; + blk_qc_t ret; - if (workingset_read) + psi_memstall_enter(&pflags); + ret = generic_make_request(bio); psi_memstall_leave(&pflags); - return ret; + return ret; + } + + return generic_make_request(bio); } EXPORT_SYMBOL(submit_bio); -- cgit v1.2.3 From 0376e9efe18388bd486a65edbc16d34b84bddc8f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 28 Apr 2020 13:27:55 +0200 Subject: block: replace BIO_QUEUE_ENTERED with BIO_CGROUP_ACCT BIO_QUEUE_ENTERED is only used for cgroup accounting now, so rename the flag and move setting it into the cgroup code. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-merge.c | 10 ---------- include/linux/blk-cgroup.h | 10 ++++++---- include/linux/blk_types.h | 2 +- 3 files changed, 7 insertions(+), 15 deletions(-) (limited to 'block') diff --git a/block/blk-merge.c b/block/blk-merge.c index c49eb3bdd0be..a04e991b5ded 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -336,16 +336,6 @@ void __blk_queue_split(struct request_queue *q, struct bio **bio, /* there isn't chance to merge the splitted bio */ split->bi_opf |= REQ_NOMERGE; - /* - * Since we're recursing into make_request here, ensure - * that we mark this bio as already having entered the queue. - * If not, and the queue is going away, we can get stuck - * forever on waiting for the queue reference to drop. But - * that will never happen, as we're already holding a - * reference to it. - */ - bio_set_flag(*bio, BIO_QUEUE_ENTERED); - bio_chain(split, *bio); trace_block_split(q, split, (*bio)->bi_iter.bi_sector); generic_make_request(*bio); diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 35f8ffe92b70..4deb8bb7b6af 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -607,12 +607,14 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q, u64_stats_update_begin(&bis->sync); /* - * If the bio is flagged with BIO_QUEUE_ENTERED it means this - * is a split bio and we would have already accounted for the - * size of the bio. + * If the bio is flagged with BIO_CGROUP_ACCT it means this is a + * split bio and we would have already accounted for the size of + * the bio. */ - if (!bio_flagged(bio, BIO_QUEUE_ENTERED)) + if (!bio_flagged(bio, BIO_CGROUP_ACCT)) { + bio_set_flag(bio, BIO_CGROUP_ACCT); bis->cur.bytes[rwd] += bio->bi_iter.bi_size; + } bis->cur.ios[rwd]++; u64_stats_update_end(&bis->sync); diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 31eb92876be7..90895d594e64 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -220,7 +220,7 @@ enum { * throttling rules. Don't do it again. */ BIO_TRACE_COMPLETION, /* bio_endio() should trace the final completion * of this bio. */ - BIO_QUEUE_ENTERED, /* can use blk_queue_enter_live() */ + BIO_CGROUP_ACCT, /* has been accounted to a cgroup */ BIO_TRACKED, /* set if bio goes through the rq_qos path */ BIO_FLAG_LAST }; -- cgit v1.2.3 From accea322f5439df22b19465bbe67b836f36165e8 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 28 Apr 2020 13:27:56 +0200 Subject: block: add a bio_queue_enter helper Add a little helper that passes the right nowait flag to blk_queue_enter based on the bio flag, and terminates the bio with the right error code if entering the queue fails. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 50 ++++++++++++++++++++++++-------------------------- 1 file changed, 24 insertions(+), 26 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 81a291085c6c..7f11560bfddb 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -440,6 +440,23 @@ int blk_queue_enter(struct request_queue *q, blk_mq_req_flags_t flags) } } +static inline int bio_queue_enter(struct bio *bio) +{ + struct request_queue *q = bio->bi_disk->queue; + bool nowait = bio->bi_opf & REQ_NOWAIT; + int ret; + + ret = blk_queue_enter(q, nowait ? BLK_MQ_REQ_NOWAIT : 0); + if (unlikely(ret)) { + if (nowait && !blk_queue_dying(q)) + bio_wouldblock_error(bio); + else + bio_io_error(bio); + } + + return ret; +} + void blk_queue_exit(struct request_queue *q) { percpu_ref_put(&q->q_usage_counter); @@ -1049,10 +1066,8 @@ blk_qc_t generic_make_request(struct bio *bio) current->bio_list = bio_list_on_stack; do { struct request_queue *q = bio->bi_disk->queue; - blk_mq_req_flags_t flags = bio->bi_opf & REQ_NOWAIT ? - BLK_MQ_REQ_NOWAIT : 0; - if (likely(blk_queue_enter(q, flags) == 0)) { + if (likely(bio_queue_enter(bio) == 0)) { struct bio_list lower, same; /* Create a fresh bio_list for all subordinate requests */ @@ -1079,12 +1094,6 @@ blk_qc_t generic_make_request(struct bio *bio) bio_list_merge(&bio_list_on_stack[0], &lower); bio_list_merge(&bio_list_on_stack[0], &same); bio_list_merge(&bio_list_on_stack[0], &bio_list_on_stack[1]); - } else { - if (unlikely(!blk_queue_dying(q) && - (bio->bi_opf & REQ_NOWAIT))) - bio_wouldblock_error(bio); - else - bio_io_error(bio); } bio = bio_list_pop(&bio_list_on_stack[0]); } while (bio); @@ -1106,30 +1115,19 @@ EXPORT_SYMBOL(generic_make_request); blk_qc_t direct_make_request(struct bio *bio) { struct request_queue *q = bio->bi_disk->queue; - bool nowait = bio->bi_opf & REQ_NOWAIT; blk_qc_t ret; - if (WARN_ON_ONCE(q->make_request_fn)) - goto io_error; - if (!generic_make_request_checks(bio)) + if (WARN_ON_ONCE(q->make_request_fn)) { + bio_io_error(bio); return BLK_QC_T_NONE; - - if (unlikely(blk_queue_enter(q, nowait ? BLK_MQ_REQ_NOWAIT : 0))) { - if (nowait && !blk_queue_dying(q)) - goto would_block; - goto io_error; } - + if (!generic_make_request_checks(bio)) + return BLK_QC_T_NONE; + if (unlikely(bio_queue_enter(bio))) + return BLK_QC_T_NONE; ret = blk_mq_make_request(q, bio); blk_queue_exit(q); return ret; - -would_block: - bio_wouldblock_error(bio); - return BLK_QC_T_NONE; -io_error: - bio_io_error(bio); - return BLK_QC_T_NONE; } EXPORT_SYMBOL_GPL(direct_make_request); -- cgit v1.2.3 From 54c52e10dc9b939084a7e6e3d32ce8fd8dee7898 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 13 Apr 2020 12:27:55 -0400 Subject: blk-iocost: switch to fixed non-auto-decaying use_delay The use_delay mechanism was introduced by blk-iolatency to hold memory allocators accountable for the reclaim and other shared IOs they cause. The duration of the delay is dynamically balanced between iolatency increasing the value on each target miss and it auto-decaying as time passes and threads get delayed on it. While this works well for iolatency, iocost's control model isn't compatible with it. There is no repeated "violation" events which can be balanced against auto-decaying. iocost instead knows how much a given cgroup is over budget and wants to prevent that cgroup from issuing IOs while over budget. Until now, iocost has been adding the cost of force-issued IOs. However, this doesn't reflect the amount which is already over budget and is simply not enough to counter the auto-decaying allowing anon-memory leaking low priority cgroup to go over its alloted share of IOs. As auto-decaying doesn't make much sense for iocost, this patch introduces a different mode of operation for use_delay - when blkcg_set_delay() are used insted of blkcg_add/use_delay(), the delay duration is not auto-decayed until it is explicitly cleared with blkcg_clear_delay(). iocost is updated to keep the delay duration synchronized to the budget overage amount. With this change, iocost can effectively police cgroups which generate significant amount of force-issued IOs. Signed-off-by: Tejun Heo Cc: Josef Bacik Signed-off-by: Jens Axboe --- block/blk-cgroup.c | 6 ++++++ block/blk-iocost.c | 23 +++++++++-------------- include/linux/blk-cgroup.h | 43 +++++++++++++++++++++++++++++++++---------- 3 files changed, 48 insertions(+), 24 deletions(-) (limited to 'block') diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c index c5dc833212e1..0a63c6cbbcb1 100644 --- a/block/blk-cgroup.c +++ b/block/blk-cgroup.c @@ -1530,6 +1530,10 @@ static void blkcg_scale_delay(struct blkcg_gq *blkg, u64 now) { u64 old = atomic64_read(&blkg->delay_start); + /* negative use_delay means no scaling, see blkcg_set_delay() */ + if (atomic_read(&blkg->use_delay) < 0) + return; + /* * We only want to scale down every second. The idea here is that we * want to delay people for min(delay_nsec, NSEC_PER_SEC) in a certain @@ -1717,6 +1721,8 @@ void blkcg_schedule_throttle(struct request_queue *q, bool use_memdelay) */ void blkcg_add_delay(struct blkcg_gq *blkg, u64 now, u64 delta) { + if (WARN_ON_ONCE(atomic_read(&blkg->use_delay) < 0)) + return; blkcg_scale_delay(blkg, now); atomic64_add(delta, &blkg->delay_nsec); } diff --git a/block/blk-iocost.c b/block/blk-iocost.c index db35ee682294..a8e99ef76a08 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -1209,14 +1209,14 @@ static enum hrtimer_restart iocg_waitq_timer_fn(struct hrtimer *timer) return HRTIMER_NORESTART; } -static bool iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now, u64 cost) +static bool iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now) { struct ioc *ioc = iocg->ioc; struct blkcg_gq *blkg = iocg_to_blkg(iocg); u64 vtime = atomic64_read(&iocg->vtime); u64 vmargin = ioc->margin_us * now->vrate; u64 margin_ns = ioc->margin_us * NSEC_PER_USEC; - u64 expires, oexpires; + u64 delta_ns, expires, oexpires; u32 hw_inuse; /* debt-adjust vtime */ @@ -1233,15 +1233,10 @@ static bool iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now, u64 cost) return false; /* use delay */ - if (cost) { - u64 cost_ns = DIV64_U64_ROUND_UP(cost * NSEC_PER_USEC, - now->vrate); - blkcg_add_delay(blkg, now->now_ns, cost_ns); - } - blkcg_use_delay(blkg); - - expires = now->now_ns + DIV64_U64_ROUND_UP(vtime - now->vnow, - now->vrate) * NSEC_PER_USEC; + delta_ns = DIV64_U64_ROUND_UP(vtime - now->vnow, + now->vrate) * NSEC_PER_USEC; + blkcg_set_delay(blkg, delta_ns); + expires = now->now_ns + delta_ns; /* if already active and close enough, don't bother */ oexpires = ktime_to_ns(hrtimer_get_softexpires(&iocg->delay_timer)); @@ -1260,7 +1255,7 @@ static enum hrtimer_restart iocg_delay_timer_fn(struct hrtimer *timer) struct ioc_now now; ioc_now(iocg->ioc, &now); - iocg_kick_delay(iocg, &now, 0); + iocg_kick_delay(iocg, &now); return HRTIMER_NORESTART; } @@ -1378,7 +1373,7 @@ static void ioc_timer_fn(struct timer_list *timer) atomic64_read(&iocg->abs_vdebt)) { /* might be oversleeping vtime / hweight changes, kick */ iocg_kick_waitq(iocg, &now); - iocg_kick_delay(iocg, &now, 0); + iocg_kick_delay(iocg, &now); } else if (iocg_is_idle(iocg)) { /* no waiter and idle, deactivate */ iocg->last_inuse = iocg->inuse; @@ -1737,7 +1732,7 @@ static void ioc_rqos_throttle(struct rq_qos *rqos, struct bio *bio) */ if (bio_issue_as_root_blkg(bio) || fatal_signal_pending(current)) { atomic64_add(abs_cost, &iocg->abs_vdebt); - if (iocg_kick_delay(iocg, &now, cost)) + if (iocg_kick_delay(iocg, &now)) blkcg_schedule_throttle(rqos->q, (bio->bi_opf & REQ_SWAP) == REQ_SWAP); return; diff --git a/include/linux/blk-cgroup.h b/include/linux/blk-cgroup.h index 4deb8bb7b6af..a57ebe2f00ab 100644 --- a/include/linux/blk-cgroup.h +++ b/include/linux/blk-cgroup.h @@ -631,6 +631,8 @@ static inline bool blkcg_bio_issue_check(struct request_queue *q, static inline void blkcg_use_delay(struct blkcg_gq *blkg) { + if (WARN_ON_ONCE(atomic_read(&blkg->use_delay) < 0)) + return; if (atomic_add_return(1, &blkg->use_delay) == 1) atomic_inc(&blkg->blkcg->css.cgroup->congestion_count); } @@ -639,6 +641,8 @@ static inline int blkcg_unuse_delay(struct blkcg_gq *blkg) { int old = atomic_read(&blkg->use_delay); + if (WARN_ON_ONCE(old < 0)) + return 0; if (old == 0) return 0; @@ -663,20 +667,39 @@ static inline int blkcg_unuse_delay(struct blkcg_gq *blkg) return 1; } +/** + * blkcg_set_delay - Enable allocator delay mechanism with the specified delay amount + * @blkg: target blkg + * @delay: delay duration in nsecs + * + * When enabled with this function, the delay is not decayed and must be + * explicitly cleared with blkcg_clear_delay(). Must not be mixed with + * blkcg_[un]use_delay() and blkcg_add_delay() usages. + */ +static inline void blkcg_set_delay(struct blkcg_gq *blkg, u64 delay) +{ + int old = atomic_read(&blkg->use_delay); + + /* We only want 1 person setting the congestion count for this blkg. */ + if (!old && atomic_cmpxchg(&blkg->use_delay, old, -1) == old) + atomic_inc(&blkg->blkcg->css.cgroup->congestion_count); + + atomic64_set(&blkg->delay_nsec, delay); +} + +/** + * blkcg_clear_delay - Disable allocator delay mechanism + * @blkg: target blkg + * + * Disable use_delay mechanism. See blkcg_set_delay(). + */ static inline void blkcg_clear_delay(struct blkcg_gq *blkg) { int old = atomic_read(&blkg->use_delay); - if (!old) - return; + /* We only want 1 person clearing the congestion count for this blkg. */ - while (old) { - int cur = atomic_cmpxchg(&blkg->use_delay, old, 0); - if (cur == old) { - atomic_dec(&blkg->blkcg->css.cgroup->congestion_count); - break; - } - old = cur; - } + if (old && atomic_cmpxchg(&blkg->use_delay, old, 0) == old) + atomic_dec(&blkg->blkcg->css.cgroup->congestion_count); } void blkcg_add_delay(struct blkcg_gq *blkg, u64 now, u64 delta); -- cgit v1.2.3 From cd006509b0a93cb7ee9d9fd50ae274098997a460 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 13 Apr 2020 12:27:56 -0400 Subject: blk-iocost: account for IO size when testing latencies On each IO completion, iocost decides whether the IO met or missed its latency target. Currently, the targets are fixed numbers per IO type. While this can be good enough for loose latency targets way higher than typical completion latencies, the effect of IO size makes it difficult to tighten the latency target - a target adequate for 4k IOs might be too tight for 512k IOs and vice-versa. iocost already has all the necessary information to account for different IO sizes when testing whether the latency target is met as iocost can calculate the size vtime cost of a given IO. This patch updates the completion path to calculate the size vtime cost of the IO, deduct the nsec equivalent from the observed latency and use the adjusted value to decide whether the target is met. This makes latency targets independent from IO size and enables determining adequate latency targets with fixed size fio runs. Signed-off-by: Tejun Heo Cc: Andy Newell Signed-off-by: Jens Axboe --- block/Kconfig | 1 + block/blk-iocost.c | 33 +++++++++++++++++++++++++++++++-- 2 files changed, 32 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/Kconfig b/block/Kconfig index 3bc76bb113a0..41cb34b0fcd1 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -146,6 +146,7 @@ config BLK_CGROUP_IOLATENCY config BLK_CGROUP_IOCOST bool "Enable support for cost model based cgroup IO controller" depends on BLK_CGROUP=y + select BLK_RQ_IO_DATA_LEN select BLK_RQ_ALLOC_TIME ---help--- Enabling this option enables the .weight interface for cost diff --git a/block/blk-iocost.c b/block/blk-iocost.c index a8e99ef76a08..9a667dd75eef 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -260,6 +260,7 @@ enum { VTIME_PER_SEC_SHIFT = 37, VTIME_PER_SEC = 1LLU << VTIME_PER_SEC_SHIFT, VTIME_PER_USEC = VTIME_PER_SEC / USEC_PER_SEC, + VTIME_PER_NSEC = VTIME_PER_SEC / NSEC_PER_SEC, /* bound vrate adjustments within two orders of magnitude */ VRATE_MIN_PPM = 10000, /* 1% */ @@ -1668,6 +1669,31 @@ static u64 calc_vtime_cost(struct bio *bio, struct ioc_gq *iocg, bool is_merge) return cost; } +static void calc_size_vtime_cost_builtin(struct request *rq, struct ioc *ioc, + u64 *costp) +{ + unsigned int pages = blk_rq_stats_sectors(rq) >> IOC_SECT_TO_PAGE_SHIFT; + + switch (req_op(rq)) { + case REQ_OP_READ: + *costp = pages * ioc->params.lcoefs[LCOEF_RPAGE]; + break; + case REQ_OP_WRITE: + *costp = pages * ioc->params.lcoefs[LCOEF_WPAGE]; + break; + default: + *costp = 0; + } +} + +static u64 calc_size_vtime_cost(struct request *rq, struct ioc *ioc) +{ + u64 cost; + + calc_size_vtime_cost_builtin(rq, ioc, &cost); + return cost; +} + static void ioc_rqos_throttle(struct rq_qos *rqos, struct bio *bio) { struct blkcg_gq *blkg = bio->bi_blkg; @@ -1837,7 +1863,7 @@ static void ioc_rqos_done_bio(struct rq_qos *rqos, struct bio *bio) static void ioc_rqos_done(struct rq_qos *rqos, struct request *rq) { struct ioc *ioc = rqos_to_ioc(rqos); - u64 on_q_ns, rq_wait_ns; + u64 on_q_ns, rq_wait_ns, size_nsec; int pidx, rw; if (!ioc->enabled || !rq->alloc_time_ns || !rq->start_time_ns) @@ -1858,8 +1884,10 @@ static void ioc_rqos_done(struct rq_qos *rqos, struct request *rq) on_q_ns = ktime_get_ns() - rq->alloc_time_ns; rq_wait_ns = rq->start_time_ns - rq->alloc_time_ns; + size_nsec = div64_u64(calc_size_vtime_cost(rq, ioc), VTIME_PER_NSEC); - if (on_q_ns <= ioc->params.qos[pidx] * NSEC_PER_USEC) + if (on_q_ns <= size_nsec || + on_q_ns - size_nsec <= ioc->params.qos[pidx] * NSEC_PER_USEC) this_cpu_inc(ioc->pcpu_stat->missed[rw].nr_met); else this_cpu_inc(ioc->pcpu_stat->missed[rw].nr_missed); @@ -2267,6 +2295,7 @@ static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input, spin_lock_irq(&ioc->lock); if (enable) { + blk_stat_enable_accounting(ioc->rqos.q); blk_queue_flag_set(QUEUE_FLAG_RQ_ALLOC_TIME, ioc->rqos.q); ioc->enabled = true; } else { -- cgit v1.2.3 From 2e194422f1eb4cdf5d6697bcfe0bbaf3059bbb5e Mon Sep 17 00:00:00 2001 From: Weiping Zhang Date: Thu, 7 May 2020 21:03:39 +0800 Subject: block: free both rq_map and request Allocation: __blk_mq_alloc_rq_map blk_mq_alloc_rq_map blk_mq_alloc_rq_map tags = blk_mq_init_tags : kzalloc_node: tags->rqs = kcalloc_node tags->static_rqs = kcalloc_node blk_mq_alloc_rqs p = alloc_pages_node tags->static_rqs[i] = p + offset; Free: blk_mq_free_rq_map kfree(tags->rqs); kfree(tags->static_rqs); blk_mq_free_tags kfree(tags); The page allocated in blk_mq_alloc_rqs cannot be released, so we should use blk_mq_free_map_and_requests here. blk_mq_free_map_and_requests blk_mq_free_rqs __free_pages : cleanup for blk_mq_alloc_rqs blk_mq_free_rq_map : cleanup for blk_mq_alloc_rq_map Signed-off-by: Weiping Zhang Reviewed-by: Ming Lei Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index bcc3a2397d4a..e9643b0d6860 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3006,7 +3006,7 @@ static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) out_unwind: while (--i >= 0) - blk_mq_free_rq_map(set->tags[i]); + blk_mq_free_map_and_requests(set, i); return -ENOMEM; } -- cgit v1.2.3 From a2584e43f5672e2715c0c5ca28ccff3b9f381581 Mon Sep 17 00:00:00 2001 From: Weiping Zhang Date: Thu, 7 May 2020 21:03:56 +0800 Subject: block: save previous hardware queue count before udpate blk_mq_realloc_tag_set_tags will update set->nr_hw_queues, so save old set->nr_hw_queues before call this function. Signed-off-by: Weiping Zhang Reviewed-by: Bart Van Assche Reviewed-by: Ming Lei Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index e9643b0d6860..9e518aefc04b 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3358,11 +3358,11 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, blk_mq_sysfs_unregister(q); } + prev_nr_hw_queues = set->nr_hw_queues; if (blk_mq_realloc_tag_set_tags(set, set->nr_hw_queues, nr_hw_queues) < 0) goto reregister; - prev_nr_hw_queues = set->nr_hw_queues; set->nr_hw_queues = nr_hw_queues; blk_mq_update_queue_map(set); fallback: -- cgit v1.2.3 From fd689871bbfbb41cd77379d3e9e5f4def0f7d6c6 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 7 May 2020 21:04:08 +0800 Subject: block: alloc map and request for new hardware queue Alloc new map and request for new hardware queue when increse hardware queue count. Before this patch, it will show a warning for each new hardware queue, but it's not enough, these hctx have no maps and reqeust, when a bio was mapped to these hardware queue, it will trigger kernel panic when get request from these hctx. Test environment: * A NVMe disk supports 128 io queues * 96 cpus in system A corner case can always trigger this panic, there are 96 io queues allocated for HCTX_TYPE_DEFAULT type, the corresponding kernel log: nvme nvme0: 96/0/0 default/read/poll queues. Now we set nvme write queues to 96, then nvme will alloc others(32) queues for read, but blk_mq_update_nr_hw_queues does not alloc map and request for these new added io queues. So when process read nvme disk, it will trigger kernel panic when get request from these hardware context. Reproduce script: nr=$(expr `cat /sys/block/nvme0n1/device/queue_count` - 1) echo $nr > /sys/module/nvme/parameters/write_queues echo 1 > /sys/block/nvme0n1/device/reset_controller dd if=/dev/nvme0n1 of=/dev/null bs=4K count=1 [ 8040.805626] ------------[ cut here ]------------ [ 8040.805627] WARNING: CPU: 82 PID: 12921 at block/blk-mq.c:2578 blk_mq_map_swqueue+0x2b6/0x2c0 [ 8040.805627] Modules linked in: nvme nvme_core nf_conntrack_netlink xt_addrtype br_netfilter overlay xt_CHECKSUM xt_MASQUERADE xt_conntrack ipt_REJECT nft_counter nf_nat_tftp nf_conntrack_tftp nft_masq nf_tables_set nft_fib_inet nft_f ib_ipv4 nft_fib_ipv6 nft_fib nft_reject_inet nf_reject_ipv4 nf_reject_ipv6 nft_reject nft_ct nft_chain_nat nf_nat nf_conntrack tun bridge nf_defrag_ipv6 nf_defrag_ipv4 stp llc ip6_tables ip_tables nft_compat rfkill ip_set nf_tables nfne tlink sunrpc intel_rapl_msr intel_rapl_common skx_edac nfit libnvdimm x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass ipmi_ssif crct10dif_pclmul crc32_pclmul iTCO_wdt iTCO_vendor_support ghash_clmulni_intel intel_ cstate intel_uncore raid0 joydev intel_rapl_perf ipmi_si pcspkr mei_me ioatdma sg ipmi_devintf mei i2c_i801 dca lpc_ich ipmi_msghandler acpi_power_meter acpi_pad xfs libcrc32c sd_mod ast i2c_algo_bit drm_vram_helper drm_ttm_helper ttm d rm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops [ 8040.805637] ahci drm i40e libahci crc32c_intel libata t10_pi wmi dm_mirror dm_region_hash dm_log dm_mod [last unloaded: nvme_core] [ 8040.805640] CPU: 82 PID: 12921 Comm: kworker/u194:2 Kdump: loaded Tainted: G W 5.6.0-rc5.78317c+ #2 [ 8040.805640] Hardware name: Inspur SA5212M5/YZMB-00882-104, BIOS 4.0.9 08/27/2019 [ 8040.805641] Workqueue: nvme-reset-wq nvme_reset_work [nvme] [ 8040.805642] RIP: 0010:blk_mq_map_swqueue+0x2b6/0x2c0 [ 8040.805643] Code: 00 00 00 00 00 41 83 c5 01 44 39 6d 50 77 b8 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 8b bb 98 00 00 00 89 d6 e8 8c 81 03 00 eb 83 <0f> 0b e9 52 ff ff ff 0f 1f 00 0f 1f 44 00 00 41 57 48 89 f1 41 56 [ 8040.805643] RSP: 0018:ffffba590d2e7d48 EFLAGS: 00010246 [ 8040.805643] RAX: 0000000000000000 RBX: ffff9f013e1ba800 RCX: 000000000000003d [ 8040.805644] RDX: ffff9f00ffff6000 RSI: 0000000000000003 RDI: ffff9ed200246d90 [ 8040.805644] RBP: ffff9f00f6a79860 R08: 0000000000000000 R09: 000000000000003d [ 8040.805645] R10: 0000000000000001 R11: ffff9f0138c3d000 R12: ffff9f00fb3a9008 [ 8040.805645] R13: 000000000000007f R14: ffffffff96822660 R15: 000000000000005f [ 8040.805645] FS: 0000000000000000(0000) GS:ffff9f013fa80000(0000) knlGS:0000000000000000 [ 8040.805646] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8040.805646] CR2: 00007f7f397fa6f8 CR3: 0000003d8240a002 CR4: 00000000007606e0 [ 8040.805647] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 8040.805647] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 8040.805647] PKRU: 55555554 [ 8040.805647] Call Trace: [ 8040.805649] blk_mq_update_nr_hw_queues+0x31b/0x390 [ 8040.805650] nvme_reset_work+0xb4b/0xeab [nvme] [ 8040.805651] process_one_work+0x1a7/0x370 [ 8040.805652] worker_thread+0x1c9/0x380 [ 8040.805653] ? max_active_store+0x80/0x80 [ 8040.805655] kthread+0x112/0x130 [ 8040.805656] ? __kthread_parkme+0x70/0x70 [ 8040.805657] ret_from_fork+0x35/0x40 [ 8040.805658] ---[ end trace b5f13b1e73ccb5d3 ]--- [ 8229.365135] BUG: kernel NULL pointer dereference, address: 0000000000000004 [ 8229.365165] #PF: supervisor read access in kernel mode [ 8229.365178] #PF: error_code(0x0000) - not-present page [ 8229.365191] PGD 0 P4D 0 [ 8229.365201] Oops: 0000 [#1] SMP PTI [ 8229.365212] CPU: 77 PID: 13024 Comm: dd Kdump: loaded Tainted: G W 5.6.0-rc5.78317c+ #2 [ 8229.365232] Hardware name: Inspur SA5212M5/YZMB-00882-104, BIOS 4.0.9 08/27/2019 [ 8229.365253] RIP: 0010:blk_mq_get_tag+0x227/0x250 [ 8229.365265] Code: 44 24 04 44 01 e0 48 8b 74 24 38 65 48 33 34 25 28 00 00 00 75 33 48 83 c4 40 5b 5d 41 5c 41 5d 41 5e c3 48 8d 68 10 4c 89 ef <44> 8b 60 04 48 89 ee e8 dd f9 ff ff 83 f8 ff 75 c8 e9 67 fe ff ff [ 8229.365304] RSP: 0018:ffffba590e977970 EFLAGS: 00010246 [ 8229.365317] RAX: 0000000000000000 RBX: ffff9f00f6a79860 RCX: ffffba590e977998 [ 8229.365333] RDX: 0000000000000000 RSI: ffff9f012039b140 RDI: ffffba590e977a38 [ 8229.365349] RBP: 0000000000000010 R08: ffffda58ff94e190 R09: ffffda58ff94e198 [ 8229.365365] R10: 0000000000000011 R11: ffff9f00f6a79860 R12: 0000000000000000 [ 8229.365381] R13: ffffba590e977a38 R14: ffff9f012039b140 R15: 0000000000000001 [ 8229.365397] FS: 00007f481c230580(0000) GS:ffff9f013f940000(0000) knlGS:0000000000000000 [ 8229.365415] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 8229.365428] CR2: 0000000000000004 CR3: 0000005f35e26004 CR4: 00000000007606e0 [ 8229.365444] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 8229.365460] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 8229.365476] PKRU: 55555554 [ 8229.365484] Call Trace: [ 8229.365498] ? finish_wait+0x80/0x80 [ 8229.365512] blk_mq_get_request+0xcb/0x3f0 [ 8229.365525] blk_mq_make_request+0x143/0x5d0 [ 8229.365538] generic_make_request+0xcf/0x310 [ 8229.365553] ? scan_shadow_nodes+0x30/0x30 [ 8229.365564] submit_bio+0x3c/0x150 [ 8229.365576] mpage_readpages+0x163/0x1a0 [ 8229.365588] ? blkdev_direct_IO+0x490/0x490 [ 8229.365601] read_pages+0x6b/0x190 [ 8229.365612] __do_page_cache_readahead+0x1c1/0x1e0 [ 8229.365626] ondemand_readahead+0x182/0x2f0 [ 8229.365639] generic_file_buffered_read+0x590/0xab0 [ 8229.365655] new_sync_read+0x12a/0x1c0 [ 8229.365666] vfs_read+0x8a/0x140 [ 8229.365676] ksys_read+0x59/0xd0 [ 8229.365688] do_syscall_64+0x55/0x1d0 [ 8229.365700] entry_SYSCALL_64_after_hwframe+0x44/0xa9 Signed-off-by: Ming Lei Signed-off-by: Weiping Zhang Tested-by: Weiping Zhang Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-mq.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 9e518aefc04b..d0fda6cf38f5 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2533,18 +2533,6 @@ static void blk_mq_map_swqueue(struct request_queue *q) * If the cpu isn't present, the cpu is mapped to first hctx. */ for_each_possible_cpu(i) { - hctx_idx = set->map[HCTX_TYPE_DEFAULT].mq_map[i]; - /* unmapped hw queue can be remapped after CPU topo changed */ - if (!set->tags[hctx_idx] && - !__blk_mq_alloc_rq_map(set, hctx_idx)) { - /* - * If tags initialization fail for some hctx, - * that hctx won't be brought online. In this - * case, remap the current ctx to hctx[0] which - * is guaranteed to always have tags allocated - */ - set->map[HCTX_TYPE_DEFAULT].mq_map[i] = 0; - } ctx = per_cpu_ptr(q->queue_ctx, i); for (j = 0; j < set->nr_maps; j++) { @@ -2553,6 +2541,18 @@ static void blk_mq_map_swqueue(struct request_queue *q) HCTX_TYPE_DEFAULT, i); continue; } + hctx_idx = set->map[j].mq_map[i]; + /* unmapped hw queue can be remapped after CPU topo changed */ + if (!set->tags[hctx_idx] && + !__blk_mq_alloc_rq_map(set, hctx_idx)) { + /* + * If tags initialization fail for some hctx, + * that hctx won't be brought online. In this + * case, remap the current ctx to hctx[0] which + * is guaranteed to always have tags allocated + */ + set->map[j].mq_map[i] = 0; + } hctx = blk_mq_map_queue_type(q, j, i); ctx->hctxs[j] = hctx; -- cgit v1.2.3 From 03b63b029dcb394c00736c4ce1a8d07e13e458da Mon Sep 17 00:00:00 2001 From: Weiping Zhang Date: Thu, 7 May 2020 21:04:22 +0800 Subject: block: rename __blk_mq_alloc_rq_map rename __blk_mq_alloc_rq_map to __blk_mq_alloc_map_and_request, actually it alloc both map and request, make function name align with function. Signed-off-by: Weiping Zhang Reviewed-by: Ming Lei Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-mq.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index d0fda6cf38f5..4c456a23a4bf 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2485,7 +2485,8 @@ static void blk_mq_init_cpu_queues(struct request_queue *q, } } -static bool __blk_mq_alloc_rq_map(struct blk_mq_tag_set *set, int hctx_idx) +static bool __blk_mq_alloc_map_and_request(struct blk_mq_tag_set *set, + int hctx_idx) { int ret = 0; @@ -2544,7 +2545,7 @@ static void blk_mq_map_swqueue(struct request_queue *q) hctx_idx = set->map[j].mq_map[i]; /* unmapped hw queue can be remapped after CPU topo changed */ if (!set->tags[hctx_idx] && - !__blk_mq_alloc_rq_map(set, hctx_idx)) { + !__blk_mq_alloc_map_and_request(set, hctx_idx)) { /* * If tags initialization fail for some hctx, * that hctx won't be brought online. In this @@ -2999,7 +3000,7 @@ static int __blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) int i; for (i = 0; i < set->nr_hw_queues; i++) - if (!__blk_mq_alloc_rq_map(set, i)) + if (!__blk_mq_alloc_map_and_request(set, i)) goto out_unwind; return 0; -- cgit v1.2.3 From 79fab5287922900725df1394034de2e04b058907 Mon Sep 17 00:00:00 2001 From: Weiping Zhang Date: Thu, 7 May 2020 21:04:42 +0800 Subject: block: rename blk_mq_alloc_rq_maps rename blk_mq_alloc_rq_maps to blk_mq_alloc_map_and_requests, this function allocs both map and request, make function name align with funtion. Signed-off-by: Weiping Zhang Reviewed-by: Ming Lei Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-mq.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 4c456a23a4bf..bc34d6b572b6 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3017,7 +3017,7 @@ out_unwind: * may reduce the depth asked for, if memory is tight. set->queue_depth * will be updated to reflect the allocated depth. */ -static int blk_mq_alloc_rq_maps(struct blk_mq_tag_set *set) +static int blk_mq_alloc_map_and_requests(struct blk_mq_tag_set *set) { unsigned int depth; int err; @@ -3177,7 +3177,7 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set) if (ret) goto out_free_mq_map; - ret = blk_mq_alloc_rq_maps(set); + ret = blk_mq_alloc_map_and_requests(set); if (ret) goto out_free_mq_map; -- cgit v1.2.3 From 3c5d202b55d3fa9106607f99cdd5044b02b5929b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 4 May 2020 14:47:59 +0200 Subject: bdi: remove bdi_register_owner Split out a new bdi_set_owner helper to set the owner, and move the policy for creating the bdi name back into genhd.c, where it belongs. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Greg Kroah-Hartman Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/genhd.c | 8 +++++--- include/linux/backing-dev.h | 2 +- mm/backing-dev.c | 12 ++---------- 3 files changed, 8 insertions(+), 14 deletions(-) (limited to 'block') diff --git a/block/genhd.c b/block/genhd.c index c05d509877fa..27511b3d164d 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -840,13 +840,15 @@ static void __device_add_disk(struct device *parent, struct gendisk *disk, disk->flags |= GENHD_FL_SUPPRESS_PARTITION_INFO; disk->flags |= GENHD_FL_NO_PART_SCAN; } else { + struct backing_dev_info *bdi = disk->queue->backing_dev_info; + struct device *dev = disk_to_dev(disk); int ret; /* Register BDI before referencing it from bdev */ - disk_to_dev(disk)->devt = devt; - ret = bdi_register_owner(disk->queue->backing_dev_info, - disk_to_dev(disk)); + dev->devt = devt; + ret = bdi_register(bdi, "%u:%u", MAJOR(devt), MINOR(devt)); WARN_ON(ret); + bdi_set_owner(bdi, dev); blk_register_region(disk_devt(disk), disk->minors, NULL, exact_match, exact_lock, disk); } diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index c9ad5c3b7b4b..4098ed6ba6b4 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -33,7 +33,7 @@ int bdi_register(struct backing_dev_info *bdi, const char *fmt, ...); __printf(2, 0) int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args); -int bdi_register_owner(struct backing_dev_info *bdi, struct device *owner); +void bdi_set_owner(struct backing_dev_info *bdi, struct device *owner); void bdi_unregister(struct backing_dev_info *bdi); struct backing_dev_info *bdi_alloc_node(gfp_t gfp_mask, int node_id); diff --git a/mm/backing-dev.c b/mm/backing-dev.c index eb6b51e49d11..bb993f99d424 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -977,20 +977,12 @@ int bdi_register(struct backing_dev_info *bdi, const char *fmt, ...) } EXPORT_SYMBOL(bdi_register); -int bdi_register_owner(struct backing_dev_info *bdi, struct device *owner) +void bdi_set_owner(struct backing_dev_info *bdi, struct device *owner) { - int rc; - - rc = bdi_register(bdi, "%u:%u", MAJOR(owner->devt), MINOR(owner->devt)); - if (rc) - return rc; - /* Leaking owner reference... */ - WARN_ON(bdi->owner); + WARN_ON_ONCE(bdi->owner); bdi->owner = owner; get_device(owner); - return 0; } -EXPORT_SYMBOL(bdi_register_owner); /* * Remove bdi from bdi_list, and ensure that it is no longer visible -- cgit v1.2.3 From aef33c2ff8aa5e24f3f7d93806aa84ca1c2b6832 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 4 May 2020 14:48:00 +0200 Subject: bdi: simplify bdi_alloc Merge the _node vs normal version and drop the superflous gfp_t argument. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Greg Kroah-Hartman Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/blk-core.c | 2 +- drivers/mtd/mtdcore.c | 2 +- fs/super.c | 2 +- include/linux/backing-dev.h | 6 +----- mm/backing-dev.c | 7 +++---- 5 files changed, 7 insertions(+), 12 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 7f11560bfddb..285a2f8ee8d3 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -501,7 +501,7 @@ struct request_queue *__blk_alloc_queue(int node_id) if (ret) goto fail_id; - q->backing_dev_info = bdi_alloc_node(GFP_KERNEL, node_id); + q->backing_dev_info = bdi_alloc(node_id); if (!q->backing_dev_info) goto fail_split; diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 2916674208b3..39ec563d9a14 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -2036,7 +2036,7 @@ static struct backing_dev_info * __init mtd_bdi_init(char *name) struct backing_dev_info *bdi; int ret; - bdi = bdi_alloc(GFP_KERNEL); + bdi = bdi_alloc(NUMA_NO_NODE); if (!bdi) return ERR_PTR(-ENOMEM); diff --git a/fs/super.c b/fs/super.c index cd352530eca9..dd28fcd706ff 100644 --- a/fs/super.c +++ b/fs/super.c @@ -1598,7 +1598,7 @@ int super_setup_bdi_name(struct super_block *sb, char *fmt, ...) int err; va_list args; - bdi = bdi_alloc(GFP_KERNEL); + bdi = bdi_alloc(NUMA_NO_NODE); if (!bdi) return -ENOMEM; diff --git a/include/linux/backing-dev.h b/include/linux/backing-dev.h index 4098ed6ba6b4..6b3504bf7a42 100644 --- a/include/linux/backing-dev.h +++ b/include/linux/backing-dev.h @@ -36,11 +36,7 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, void bdi_set_owner(struct backing_dev_info *bdi, struct device *owner); void bdi_unregister(struct backing_dev_info *bdi); -struct backing_dev_info *bdi_alloc_node(gfp_t gfp_mask, int node_id); -static inline struct backing_dev_info *bdi_alloc(gfp_t gfp_mask) -{ - return bdi_alloc_node(gfp_mask, NUMA_NO_NODE); -} +struct backing_dev_info *bdi_alloc(int node_id); void wb_start_background_writeback(struct bdi_writeback *wb); void wb_workfn(struct work_struct *work); diff --git a/mm/backing-dev.c b/mm/backing-dev.c index bb993f99d424..1f55d5b8269f 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -865,12 +865,11 @@ static int bdi_init(struct backing_dev_info *bdi) return ret; } -struct backing_dev_info *bdi_alloc_node(gfp_t gfp_mask, int node_id) +struct backing_dev_info *bdi_alloc(int node_id) { struct backing_dev_info *bdi; - bdi = kmalloc_node(sizeof(struct backing_dev_info), - gfp_mask | __GFP_ZERO, node_id); + bdi = kzalloc_node(sizeof(*bdi), GFP_KERNEL, node_id); if (!bdi) return NULL; @@ -880,7 +879,7 @@ struct backing_dev_info *bdi_alloc_node(gfp_t gfp_mask, int node_id) } return bdi; } -EXPORT_SYMBOL(bdi_alloc_node); +EXPORT_SYMBOL(bdi_alloc); static struct rb_node **bdi_lookup_rb_node(u64 id, struct rb_node **parentp) { -- cgit v1.2.3 From 1cd925d583857ee3ead6cfbf1e4b1cd067d28591 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 4 May 2020 14:48:01 +0200 Subject: bdi: remove the name field in struct backing_dev_info The name is only printed for a not registered bdi in writeback. Use the device name there as is more useful anyway for the unlike case that the warning triggers. Signed-off-by: Christoph Hellwig Reviewed-by: Jan Kara Reviewed-by: Greg Kroah-Hartman Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/blk-core.c | 1 - drivers/mtd/mtdcore.c | 1 - fs/fs-writeback.c | 2 +- fs/super.c | 2 -- include/linux/backing-dev-defs.h | 2 -- mm/backing-dev.c | 1 - 6 files changed, 1 insertion(+), 8 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 285a2f8ee8d3..538cbc725620 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -511,7 +511,6 @@ struct request_queue *__blk_alloc_queue(int node_id) q->backing_dev_info->ra_pages = VM_READAHEAD_PAGES; q->backing_dev_info->capabilities = BDI_CAP_CGROUP_WRITEBACK; - q->backing_dev_info->name = "block"; q->node = node_id; timer_setup(&q->backing_dev_info->laptop_mode_wb_timer, diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 39ec563d9a14..fcb018ce17c3 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c @@ -2040,7 +2040,6 @@ static struct backing_dev_info * __init mtd_bdi_init(char *name) if (!bdi) return ERR_PTR(-ENOMEM); - bdi->name = name; /* * We put '-0' suffix to the name to get the same name format as we * used to get. Since this is called only once, we get a unique name. diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 76ac9c7d32ec..d85323607b49 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -2320,7 +2320,7 @@ void __mark_inode_dirty(struct inode *inode, int flags) WARN(bdi_cap_writeback_dirty(wb->bdi) && !test_bit(WB_registered, &wb->state), - "bdi-%s not registered\n", wb->bdi->name); + "bdi-%s not registered\n", bdi_dev_name(wb->bdi)); inode->dirtied_when = jiffies; if (dirtytime) diff --git a/fs/super.c b/fs/super.c index dd28fcd706ff..4991f441988e 100644 --- a/fs/super.c +++ b/fs/super.c @@ -1602,8 +1602,6 @@ int super_setup_bdi_name(struct super_block *sb, char *fmt, ...) if (!bdi) return -ENOMEM; - bdi->name = sb->s_type->name; - va_start(args, fmt); err = bdi_register_va(bdi, fmt, args); va_end(args); diff --git a/include/linux/backing-dev-defs.h b/include/linux/backing-dev-defs.h index 7367150f962a..90a7e844a098 100644 --- a/include/linux/backing-dev-defs.h +++ b/include/linux/backing-dev-defs.h @@ -193,8 +193,6 @@ struct backing_dev_info { congested_fn *congested_fn; /* Function pointer if device is md/dm */ void *congested_data; /* Pointer to aux data for congested func */ - const char *name; - struct kref refcnt; /* Reference counter for the structure */ unsigned int capabilities; /* Device capabilities */ unsigned int min_ratio; diff --git a/mm/backing-dev.c b/mm/backing-dev.c index 1f55d5b8269f..d382272bcc31 100644 --- a/mm/backing-dev.c +++ b/mm/backing-dev.c @@ -15,7 +15,6 @@ #include struct backing_dev_info noop_backing_dev_info = { - .name = "noop", .capabilities = BDI_CAP_NO_ACCT_AND_WRITEBACK, }; EXPORT_SYMBOL_GPL(noop_backing_dev_info); -- cgit v1.2.3 From aa880ad690ab6d4c53934af85fb5a43e69ecb0f5 Mon Sep 17 00:00:00 2001 From: Weiping Zhang Date: Wed, 13 May 2020 08:44:05 +0800 Subject: block: reset mapping if failed to update hardware queue count When we increase hardware queue count, blk_mq_update_queue_map will reset the mapping between cpu and hardware queue base on the hardware queue count(set->nr_hw_queues). The mapping cannot be reset if it encounters error in blk_mq_realloc_hw_ctxs, but the fallback flow will continue using it, then blk_mq_map_swqueue will touch a invalid memory, because the mapping points to a wrong hctx. blktest block/030: null_blk: module loaded Increasing nr_hw_queues to 8 fails, fallback to 1 ================================================================== BUG: KASAN: null-ptr-deref in blk_mq_map_swqueue+0x2f2/0x830 Read of size 8 at addr 0000000000000128 by task nproc/8541 CPU: 5 PID: 8541 Comm: nproc Not tainted 5.7.0-rc4-dbg+ #3 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014 Call Trace: dump_stack+0xa5/0xe6 __kasan_report.cold+0x65/0xbb kasan_report+0x45/0x60 check_memory_region+0x15e/0x1c0 __kasan_check_read+0x15/0x20 blk_mq_map_swqueue+0x2f2/0x830 __blk_mq_update_nr_hw_queues+0x3df/0x690 blk_mq_update_nr_hw_queues+0x32/0x50 nullb_device_submit_queues_store+0xde/0x160 [null_blk] configfs_write_file+0x1c4/0x250 [configfs] __vfs_write+0x4c/0x90 vfs_write+0x14b/0x2d0 ksys_write+0xdd/0x180 __x64_sys_write+0x47/0x50 do_syscall_64+0x6f/0x310 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Signed-off-by: Weiping Zhang Tested-by: Bart van Assche Signed-off-by: Jens Axboe --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index bc34d6b572b6..d82cefb0474f 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3365,8 +3365,8 @@ static void __blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, goto reregister; set->nr_hw_queues = nr_hw_queues; - blk_mq_update_queue_map(set); fallback: + blk_mq_update_queue_map(set); list_for_each_entry(q, &set->tag_list, tag_set_list) { blk_mq_realloc_hw_ctxs(set, q); if (q->nr_hw_queues != set->nr_hw_queues) { -- cgit v1.2.3 From b7d6c30333239f77f8e51423064a623acc7fd127 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 8 May 2020 16:17:55 +0800 Subject: block: fix use-after-free on cached last_lookup partition delete_partition() clears the cached last_lookup partition. However the .last_lookup cache may be overwritten by one IO path after it is cleared from delete_partition(). Then another IO path may use the cached deleting partition after hd_struct_free() is called, then use-after-free is triggered on the cached partition. Fixes the issue by the following approach: 1) always get the partition's refcount via hd_struct_try_get() before setting .last_lookup 2) move clearing .last_lookup from delete_partition() to hd_struct_free() which is the release handle of the partition's percpu-refcount, so that no IO path can cache deleteing partition via .last_lookup. It is one candidate approach of Yufen's patch[1] which adds overhead in fast path by indirect lookup which may introduce one extra cacheline in IO path. Also this patch relies on percpu-refcount's protection, and it is easier to understand and verify. [1] https://lore.kernel.org/linux-block/20200109013551.GB9655@ming.t460p/T/#t Reported-by: Yufen Yu Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig Cc: Christoph Hellwig Cc: Hou Tao Signed-off-by: Jens Axboe --- block/blk-core.c | 12 ------------ block/genhd.c | 15 ++++++++++++--- block/partitions/core.c | 12 +++++++++++- 3 files changed, 23 insertions(+), 16 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 538cbc725620..409e1a6b73b0 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1362,18 +1362,6 @@ void blk_account_io_start(struct request *rq, bool new_io) part_stat_inc(part, merges[rw]); } else { part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); - if (!hd_struct_try_get(part)) { - /* - * The partition is already being removed, - * the request will be accounted on the disk only - * - * We take a reference on disk->part0 although that - * partition will never be deleted, so we can treat - * it as any other partition. - */ - part = &rq->rq_disk->part0; - hd_struct_get(part); - } part_inc_in_flight(rq->q, part, rw); rq->part = part; } diff --git a/block/genhd.c b/block/genhd.c index 27511b3d164d..af6cba2a9332 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -344,11 +344,12 @@ static inline int sector_in_part(struct hd_struct *part, sector_t sector) * primarily used for stats accounting. * * CONTEXT: - * RCU read locked. The returned partition pointer is valid only - * while preemption is disabled. + * RCU read locked. The returned partition pointer is always valid + * because its refcount is grabbed. * * RETURNS: * Found partition on success, part0 is returned if no partition matches + * or the matched partition is being deleted. */ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) { @@ -359,17 +360,25 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) ptbl = rcu_dereference(disk->part_tbl); part = rcu_dereference(ptbl->last_lookup); - if (part && sector_in_part(part, sector)) + if (part && sector_in_part(part, sector) && hd_struct_try_get(part)) return part; for (i = 1; i < ptbl->len; i++) { part = rcu_dereference(ptbl->part[i]); if (part && sector_in_part(part, sector)) { + /* + * only live partition can be cached for lookup, + * so use-after-free on cached & deleting partition + * can be avoided + */ + if (!hd_struct_try_get(part)) + break; rcu_assign_pointer(ptbl->last_lookup, part); return part; } } + hd_struct_get(&disk->part0); return &disk->part0; } diff --git a/block/partitions/core.c b/block/partitions/core.c index 873999e2e2f2..8d8c87207fc2 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -288,6 +288,12 @@ static void hd_struct_free_work(struct work_struct *work) static void hd_struct_free(struct percpu_ref *ref) { struct hd_struct *part = container_of(ref, struct hd_struct, ref); + struct gendisk *disk = part_to_disk(part); + struct disk_part_tbl *ptbl = + rcu_dereference_protected(disk->part_tbl, 1); + + rcu_assign_pointer(ptbl->last_lookup, NULL); + put_device(disk_to_dev(disk)); INIT_RCU_WORK(&part->rcu_work, hd_struct_free_work); queue_rcu_work(system_wq, &part->rcu_work); @@ -309,8 +315,12 @@ void delete_partition(struct gendisk *disk, struct hd_struct *part) struct disk_part_tbl *ptbl = rcu_dereference_protected(disk->part_tbl, 1); + /* + * ->part_tbl is referenced in this part's release handler, so + * we have to hold the disk device + */ + get_device(disk_to_dev(part_to_disk(part))); rcu_assign_pointer(ptbl->part[part->partno], NULL); - rcu_assign_pointer(ptbl->last_lookup, NULL); kobject_put(part->holder_dir); device_del(part_to_dev(part)); -- cgit v1.2.3 From 07c4e1e834f8e7c991aa6dcb5ee0b7f2842e495d Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 8 May 2020 16:17:56 +0800 Subject: block: only define 'nr_sects_seq' in hd_part for 32bit SMP The seqcount of 'nr_sects_seq' is only needed in case of 32bit SMP, so define it just for 32bit SMP. Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig Cc: Yufen Yu Cc: Christoph Hellwig Cc: Hou Tao Signed-off-by: Jens Axboe --- block/genhd.c | 2 +- block/partitions/core.c | 2 +- include/linux/genhd.h | 9 +++++++++ 3 files changed, 11 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/genhd.c b/block/genhd.c index af6cba2a9332..1a51a9ad1035 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -1731,7 +1731,7 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) * TODO: Ideally set_capacity() and get_capacity() should be * converted to make use of bd_mutex and sequence counters. */ - seqcount_init(&disk->part0.nr_sects_seq); + hd_sects_seq_init(&disk->part0); if (hd_ref_init(&disk->part0)) { hd_free_part(&disk->part0); kfree(disk); diff --git a/block/partitions/core.c b/block/partitions/core.c index 8d8c87207fc2..297004fd2264 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -392,7 +392,7 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno, goto out_free; } - seqcount_init(&p->nr_sects_seq); + hd_sects_seq_init(p); pdev = part_to_dev(p); p->start_sect = start; diff --git a/include/linux/genhd.h b/include/linux/genhd.h index f9c226f9546a..b4744035ae58 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -68,7 +68,9 @@ struct hd_struct { * can be non-atomic on 32bit machines with 64bit sector_t. */ sector_t nr_sects; +#if BITS_PER_LONG==32 && defined(CONFIG_SMP) seqcount_t nr_sects_seq; +#endif sector_t alignment_offset; unsigned int discard_alignment; struct device __dev; @@ -274,6 +276,13 @@ static inline void disk_put_part(struct hd_struct *part) put_device(part_to_dev(part)); } +static inline void hd_sects_seq_init(struct hd_struct *p) +{ +#if BITS_PER_LONG==32 && defined(CONFIG_SMP) + seqcount_init(&p->nr_sects_seq); +#endif +} + /* * Smarter partition iterator without context limits. */ -- cgit v1.2.3 From 27eb3af9a37a85ca35f82830a8fc29753700058a Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 8 May 2020 16:17:58 +0800 Subject: block: don't hold part0's refcount in IO path gendisk can't be gone when there is IO activity, so not hold part0's refcount in IO path. Signed-off-by: Ming Lei Reviewed-by: Christoph Hellwig Cc: Yufen Yu Cc: Christoph Hellwig Cc: Hou Tao Signed-off-by: Jens Axboe --- block/blk.h | 13 ++++++------- block/genhd.c | 4 ++-- 2 files changed, 8 insertions(+), 9 deletions(-) (limited to 'block') diff --git a/block/blk.h b/block/blk.h index 73bd3b1c6938..8c3f557dd898 100644 --- a/block/blk.h +++ b/block/blk.h @@ -378,19 +378,18 @@ int bdev_resize_partition(struct block_device *bdev, int partno, int disk_expand_part_tbl(struct gendisk *disk, int target); int hd_ref_init(struct hd_struct *part); -static inline void hd_struct_get(struct hd_struct *part) -{ - percpu_ref_get(&part->ref); -} - +/* no need to get/put refcount of part0 */ static inline int hd_struct_try_get(struct hd_struct *part) { - return percpu_ref_tryget_live(&part->ref); + if (part->partno) + return percpu_ref_tryget_live(&part->ref); + return 1; } static inline void hd_struct_put(struct hd_struct *part) { - percpu_ref_put(&part->ref); + if (part->partno) + percpu_ref_put(&part->ref); } static inline void hd_free_part(struct hd_struct *part) diff --git a/block/genhd.c b/block/genhd.c index 1a51a9ad1035..afdb2c3e5b22 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -345,7 +345,8 @@ static inline int sector_in_part(struct hd_struct *part, sector_t sector) * * CONTEXT: * RCU read locked. The returned partition pointer is always valid - * because its refcount is grabbed. + * because its refcount is grabbed except for part0, which lifetime + * is same with the disk. * * RETURNS: * Found partition on success, part0 is returned if no partition matches @@ -378,7 +379,6 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) return part; } } - hd_struct_get(&disk->part0); return &disk->part0; } -- cgit v1.2.3 From e4581105771b3523ced88f781eb2672195d217aa Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 12 May 2020 17:55:46 +0900 Subject: block: rename __bio_add_pc_page to bio_add_hw_page Rename __bio_add_pc_page() to bio_add_hw_page() and explicitly pass in a max_sectors argument. This max_sectors argument can be used to specify constraints from the hardware. Signed-off-by: Christoph Hellwig [ jth: rebased and made public for blk-map.c ] Signed-off-by: Johannes Thumshirn Reviewed-by: Daniel Wagner Reviewed-by: Martin K. Petersen Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/bio.c | 65 +++++++++++++++++++++++++++++++++++---------------------- block/blk-map.c | 5 +++-- block/blk.h | 4 ++-- 3 files changed, 45 insertions(+), 29 deletions(-) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index 21cbaa6a1c20..aad0a6dad4f9 100644 --- a/block/bio.c +++ b/block/bio.c @@ -748,9 +748,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, return true; } -static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, - struct page *page, unsigned len, unsigned offset, - bool *same_page) +/* + * Try to merge a page into a segment, while obeying the hardware segment + * size limit. This is not for normal read/write bios, but for passthrough + * or Zone Append operations that we can't split. + */ +static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio, + struct page *page, unsigned len, + unsigned offset, bool *same_page) { struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; unsigned long mask = queue_segment_boundary(q); @@ -765,38 +770,32 @@ static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, } /** - * __bio_add_pc_page - attempt to add page to passthrough bio - * @q: the target queue - * @bio: destination bio - * @page: page to add - * @len: vec entry length - * @offset: vec entry offset - * @same_page: return if the merge happen inside the same page - * - * Attempt to add a page to the bio_vec maplist. This can fail for a - * number of reasons, such as the bio being full or target block device - * limitations. The target block device must allow bio's up to PAGE_SIZE, - * so it is always possible to add a single page to an empty bio. + * bio_add_hw_page - attempt to add a page to a bio with hw constraints + * @q: the target queue + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * @max_sectors: maximum number of sectors that can be added + * @same_page: return if the segment has been merged inside the same page * - * This should only be used by passthrough bios. + * Add a page to a bio while respecting the hardware max_sectors, max_segment + * and gap limitations. */ -int __bio_add_pc_page(struct request_queue *q, struct bio *bio, +int bio_add_hw_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, - bool *same_page) + unsigned int max_sectors, bool *same_page) { struct bio_vec *bvec; - /* - * cloned bio must not modify vec list - */ - if (unlikely(bio_flagged(bio, BIO_CLONED))) + if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) return 0; - if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q)) + if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors) return 0; if (bio->bi_vcnt > 0) { - if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page)) + if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page)) return len; /* @@ -823,11 +822,27 @@ int __bio_add_pc_page(struct request_queue *q, struct bio *bio, return len; } +/** + * bio_add_pc_page - attempt to add page to passthrough bio + * @q: the target queue + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * + * Attempt to add a page to the bio_vec maplist. This can fail for a + * number of reasons, such as the bio being full or target block device + * limitations. The target block device must allow bio's up to PAGE_SIZE, + * so it is always possible to add a single page to an empty bio. + * + * This should only be used by passthrough bios. + */ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { bool same_page = false; - return __bio_add_pc_page(q, bio, page, len, offset, &same_page); + return bio_add_hw_page(q, bio, page, len, offset, + queue_max_hw_sectors(q), &same_page); } EXPORT_SYMBOL(bio_add_pc_page); diff --git a/block/blk-map.c b/block/blk-map.c index b6fa343fea9f..e3e4ac48db45 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -257,6 +257,7 @@ out_bmd: static struct bio *bio_map_user_iov(struct request_queue *q, struct iov_iter *iter, gfp_t gfp_mask) { + unsigned int max_sectors = queue_max_hw_sectors(q); int j; struct bio *bio; int ret; @@ -294,8 +295,8 @@ static struct bio *bio_map_user_iov(struct request_queue *q, if (n > bytes) n = bytes; - if (!__bio_add_pc_page(q, bio, page, n, offs, - &same_page)) { + if (!bio_add_hw_page(q, bio, page, n, offs, + max_sectors, &same_page)) { if (same_page) put_page(page); break; diff --git a/block/blk.h b/block/blk.h index 8c3f557dd898..e5cd350ca379 100644 --- a/block/blk.h +++ b/block/blk.h @@ -452,8 +452,8 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size) struct request_queue *__blk_alloc_queue(int node_id); -int __bio_add_pc_page(struct request_queue *q, struct bio *bio, +int bio_add_hw_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, - bool *same_page); + unsigned int max_sectors, bool *same_page); #endif /* BLK_INTERNAL_H */ -- cgit v1.2.3 From 0512a75b98f847c2e9a4b664013424e603e202f7 Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Tue, 12 May 2020 17:55:47 +0900 Subject: block: Introduce REQ_OP_ZONE_APPEND Define REQ_OP_ZONE_APPEND to append-write sectors to a zone of a zoned block device. This is a no-merge write operation. A zone append write BIO must: * Target a zoned block device * Have a sector position indicating the start sector of the target zone * The target zone must be a sequential write zone * The BIO must not cross a zone boundary * The BIO size must not be split to ensure that a single range of LBAs is written with a single command. Implement these checks in generic_make_request_checks() using the helper function blk_check_zone_append(). To avoid write append BIO splitting, introduce the new max_zone_append_sectors queue limit attribute and ensure that a BIO size is always lower than this limit. Export this new limit through sysfs and check these limits in bio_full(). Also when a LLDD can't dispatch a request to a specific zone, it will return BLK_STS_ZONE_RESOURCE indicating this request needs to be delayed, e.g. because the zone it will be dispatched to is still write-locked. If this happens set the request aside in a local list to continue trying dispatching requests such as READ requests or a WRITE/ZONE_APPEND requests targetting other zones. This way we can still keep a high queue depth without starving other requests even if one request can't be served due to zone write-locking. Finally, make sure that the bio sector position indicates the actual write position as indicated by the device on completion. Signed-off-by: Keith Busch [ jth: added zone-append specific add_page and merge_page helpers ] Signed-off-by: Johannes Thumshirn Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Signed-off-by: Jens Axboe --- block/bio.c | 62 ++++++++++++++++++++++++++++++++++++++++++++--- block/blk-core.c | 52 +++++++++++++++++++++++++++++++++++++++ block/blk-mq.c | 27 +++++++++++++++++++++ block/blk-settings.c | 31 ++++++++++++++++++++++++ block/blk-sysfs.c | 13 ++++++++++ drivers/scsi/scsi_lib.c | 1 + include/linux/blk_types.h | 14 +++++++++++ include/linux/blkdev.h | 11 +++++++++ 8 files changed, 207 insertions(+), 4 deletions(-) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index aad0a6dad4f9..3aa3c4ce2e5e 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1025,6 +1025,50 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) return 0; } +static int __bio_iov_append_get_pages(struct bio *bio, struct iov_iter *iter) +{ + unsigned short nr_pages = bio->bi_max_vecs - bio->bi_vcnt; + unsigned short entries_left = bio->bi_max_vecs - bio->bi_vcnt; + struct request_queue *q = bio->bi_disk->queue; + unsigned int max_append_sectors = queue_max_zone_append_sectors(q); + struct bio_vec *bv = bio->bi_io_vec + bio->bi_vcnt; + struct page **pages = (struct page **)bv; + ssize_t size, left; + unsigned len, i; + size_t offset; + + if (WARN_ON_ONCE(!max_append_sectors)) + return 0; + + /* + * Move page array up in the allocated memory for the bio vecs as far as + * possible so that we can start filling biovecs from the beginning + * without overwriting the temporary page array. + */ + BUILD_BUG_ON(PAGE_PTRS_PER_BVEC < 2); + pages += entries_left * (PAGE_PTRS_PER_BVEC - 1); + + size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset); + if (unlikely(size <= 0)) + return size ? size : -EFAULT; + + for (left = size, i = 0; left > 0; left -= len, i++) { + struct page *page = pages[i]; + bool same_page = false; + + len = min_t(size_t, PAGE_SIZE - offset, left); + if (bio_add_hw_page(q, bio, page, len, offset, + max_append_sectors, &same_page) != len) + return -EINVAL; + if (same_page) + put_page(page); + offset = 0; + } + + iov_iter_advance(iter, size); + return 0; +} + /** * bio_iov_iter_get_pages - add user or kernel pages to a bio * @bio: bio to add pages to @@ -1054,10 +1098,16 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) return -EINVAL; do { - if (is_bvec) - ret = __bio_iov_bvec_add_pages(bio, iter); - else - ret = __bio_iov_iter_get_pages(bio, iter); + if (bio_op(bio) == REQ_OP_ZONE_APPEND) { + if (WARN_ON_ONCE(is_bvec)) + return -EINVAL; + ret = __bio_iov_append_get_pages(bio, iter); + } else { + if (is_bvec) + ret = __bio_iov_bvec_add_pages(bio, iter); + else + ret = __bio_iov_iter_get_pages(bio, iter); + } } while (!ret && iov_iter_count(iter) && !bio_full(bio, 0)); if (is_bvec) @@ -1460,6 +1510,10 @@ struct bio *bio_split(struct bio *bio, int sectors, BUG_ON(sectors <= 0); BUG_ON(sectors >= bio_sectors(bio)); + /* Zone append commands cannot be split */ + if (WARN_ON_ONCE(bio_op(bio) == REQ_OP_ZONE_APPEND)) + return NULL; + split = bio_clone_fast(bio, gfp, bs); if (!split) return NULL; diff --git a/block/blk-core.c b/block/blk-core.c index 409e1a6b73b0..cf5b2163edfe 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -135,6 +135,7 @@ static const char *const blk_op_name[] = { REQ_OP_NAME(ZONE_OPEN), REQ_OP_NAME(ZONE_CLOSE), REQ_OP_NAME(ZONE_FINISH), + REQ_OP_NAME(ZONE_APPEND), REQ_OP_NAME(WRITE_SAME), REQ_OP_NAME(WRITE_ZEROES), REQ_OP_NAME(SCSI_IN), @@ -240,6 +241,17 @@ static void req_bio_endio(struct request *rq, struct bio *bio, bio_advance(bio, nbytes); + if (req_op(rq) == REQ_OP_ZONE_APPEND && error == BLK_STS_OK) { + /* + * Partial zone append completions cannot be supported as the + * BIO fragments may end up not being written sequentially. + */ + if (bio->bi_iter.bi_size) + bio->bi_status = BLK_STS_IOERR; + else + bio->bi_iter.bi_sector = rq->__sector; + } + /* don't actually finish bio if it's part of flush sequence */ if (bio->bi_iter.bi_size == 0 && !(rq->rq_flags & RQF_FLUSH_SEQ)) bio_endio(bio); @@ -887,6 +899,41 @@ out: return ret; } +/* + * Check write append to a zoned block device. + */ +static inline blk_status_t blk_check_zone_append(struct request_queue *q, + struct bio *bio) +{ + sector_t pos = bio->bi_iter.bi_sector; + int nr_sectors = bio_sectors(bio); + + /* Only applicable to zoned block devices */ + if (!blk_queue_is_zoned(q)) + return BLK_STS_NOTSUPP; + + /* The bio sector must point to the start of a sequential zone */ + if (pos & (blk_queue_zone_sectors(q) - 1) || + !blk_queue_zone_is_seq(q, pos)) + return BLK_STS_IOERR; + + /* + * Not allowed to cross zone boundaries. Otherwise, the BIO will be + * split and could result in non-contiguous sectors being written in + * different zones. + */ + if (nr_sectors > q->limits.chunk_sectors) + return BLK_STS_IOERR; + + /* Make sure the BIO is small enough and will not get split */ + if (nr_sectors > q->limits.max_zone_append_sectors) + return BLK_STS_IOERR; + + bio->bi_opf |= REQ_NOMERGE; + + return BLK_STS_OK; +} + static noinline_for_stack bool generic_make_request_checks(struct bio *bio) { @@ -959,6 +1006,11 @@ generic_make_request_checks(struct bio *bio) if (!q->limits.max_write_same_sectors) goto not_supported; break; + case REQ_OP_ZONE_APPEND: + status = blk_check_zone_append(q, bio); + if (status != BLK_STS_OK) + goto end_io; + break; case REQ_OP_ZONE_RESET: case REQ_OP_ZONE_OPEN: case REQ_OP_ZONE_CLOSE: diff --git a/block/blk-mq.c b/block/blk-mq.c index d82cefb0474f..9ee695bdf873 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1183,6 +1183,19 @@ static void blk_mq_handle_dev_resource(struct request *rq, __blk_mq_requeue_request(rq); } +static void blk_mq_handle_zone_resource(struct request *rq, + struct list_head *zone_list) +{ + /* + * If we end up here it is because we cannot dispatch a request to a + * specific zone due to LLD level zone-write locking or other zone + * related resource not being available. In this case, set the request + * aside in zone_list for retrying it later. + */ + list_add(&rq->queuelist, zone_list); + __blk_mq_requeue_request(rq); +} + /* * Returns true if we did some work AND can potentially do more. */ @@ -1195,6 +1208,7 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, int errors, queued; blk_status_t ret = BLK_STS_OK; bool no_budget_avail = false; + LIST_HEAD(zone_list); if (list_empty(list)) return false; @@ -1256,6 +1270,16 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) { blk_mq_handle_dev_resource(rq, list); break; + } else if (ret == BLK_STS_ZONE_RESOURCE) { + /* + * Move the request to zone_list and keep going through + * the dispatch list to find more requests the drive can + * accept. + */ + blk_mq_handle_zone_resource(rq, &zone_list); + if (list_empty(list)) + break; + continue; } if (unlikely(ret != BLK_STS_OK)) { @@ -1267,6 +1291,9 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list, queued++; } while (!list_empty(list)); + if (!list_empty(&zone_list)) + list_splice_tail_init(&zone_list, list); + hctx->dispatched[queued_to_index(queued)]++; /* diff --git a/block/blk-settings.c b/block/blk-settings.c index 2ab1967b9716..9a2c23cd9700 100644 --- a/block/blk-settings.c +++ b/block/blk-settings.c @@ -48,6 +48,7 @@ void blk_set_default_limits(struct queue_limits *lim) lim->chunk_sectors = 0; lim->max_write_same_sectors = 0; lim->max_write_zeroes_sectors = 0; + lim->max_zone_append_sectors = 0; lim->max_discard_sectors = 0; lim->max_hw_discard_sectors = 0; lim->discard_granularity = 0; @@ -83,6 +84,7 @@ void blk_set_stacking_limits(struct queue_limits *lim) lim->max_dev_sectors = UINT_MAX; lim->max_write_same_sectors = UINT_MAX; lim->max_write_zeroes_sectors = UINT_MAX; + lim->max_zone_append_sectors = UINT_MAX; } EXPORT_SYMBOL(blk_set_stacking_limits); @@ -221,6 +223,33 @@ void blk_queue_max_write_zeroes_sectors(struct request_queue *q, } EXPORT_SYMBOL(blk_queue_max_write_zeroes_sectors); +/** + * blk_queue_max_zone_append_sectors - set max sectors for a single zone append + * @q: the request queue for the device + * @max_zone_append_sectors: maximum number of sectors to write per command + **/ +void blk_queue_max_zone_append_sectors(struct request_queue *q, + unsigned int max_zone_append_sectors) +{ + unsigned int max_sectors; + + if (WARN_ON(!blk_queue_is_zoned(q))) + return; + + max_sectors = min(q->limits.max_hw_sectors, max_zone_append_sectors); + max_sectors = min(q->limits.chunk_sectors, max_sectors); + + /* + * Signal eventual driver bugs resulting in the max_zone_append sectors limit + * being 0 due to a 0 argument, the chunk_sectors limit (zone size) not set, + * or the max_hw_sectors limit not set. + */ + WARN_ON(!max_sectors); + + q->limits.max_zone_append_sectors = max_sectors; +} +EXPORT_SYMBOL_GPL(blk_queue_max_zone_append_sectors); + /** * blk_queue_max_segments - set max hw segments for a request for this queue * @q: the request queue for the device @@ -470,6 +499,8 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, b->max_write_same_sectors); t->max_write_zeroes_sectors = min(t->max_write_zeroes_sectors, b->max_write_zeroes_sectors); + t->max_zone_append_sectors = min(t->max_zone_append_sectors, + b->max_zone_append_sectors); t->bounce_pfn = min_not_zero(t->bounce_pfn, b->bounce_pfn); t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask, diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c index fca9b158f4a0..02643e149d5e 100644 --- a/block/blk-sysfs.c +++ b/block/blk-sysfs.c @@ -218,6 +218,13 @@ static ssize_t queue_write_zeroes_max_show(struct request_queue *q, char *page) (unsigned long long)q->limits.max_write_zeroes_sectors << 9); } +static ssize_t queue_zone_append_max_show(struct request_queue *q, char *page) +{ + unsigned long long max_sectors = q->limits.max_zone_append_sectors; + + return sprintf(page, "%llu\n", max_sectors << SECTOR_SHIFT); +} + static ssize_t queue_max_sectors_store(struct request_queue *q, const char *page, size_t count) { @@ -639,6 +646,11 @@ static struct queue_sysfs_entry queue_write_zeroes_max_entry = { .show = queue_write_zeroes_max_show, }; +static struct queue_sysfs_entry queue_zone_append_max_entry = { + .attr = {.name = "zone_append_max_bytes", .mode = 0444 }, + .show = queue_zone_append_max_show, +}; + static struct queue_sysfs_entry queue_nonrot_entry = { .attr = {.name = "rotational", .mode = 0644 }, .show = queue_show_nonrot, @@ -749,6 +761,7 @@ static struct attribute *queue_attrs[] = { &queue_discard_zeroes_data_entry.attr, &queue_write_same_max_entry.attr, &queue_write_zeroes_max_entry.attr, + &queue_zone_append_max_entry.attr, &queue_nonrot_entry.attr, &queue_zoned_entry.attr, &queue_nr_zones_entry.attr, diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 0a73230a8f16..82ad0244b3d0 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1706,6 +1706,7 @@ out_put_budget: case BLK_STS_OK: break; case BLK_STS_RESOURCE: + case BLK_STS_ZONE_RESOURCE: if (atomic_read(&sdev->device_busy) || scsi_device_blocked(sdev)) ret = BLK_STS_DEV_RESOURCE; diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 90895d594e64..b90dca1fa430 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -63,6 +63,18 @@ typedef u8 __bitwise blk_status_t; */ #define BLK_STS_DEV_RESOURCE ((__force blk_status_t)13) +/* + * BLK_STS_ZONE_RESOURCE is returned from the driver to the block layer if zone + * related resources are unavailable, but the driver can guarantee the queue + * will be rerun in the future once the resources become available again. + * + * This is different from BLK_STS_DEV_RESOURCE in that it explicitly references + * a zone specific resource and IO to a different zone on the same device could + * still be served. Examples of that are zones that are write-locked, but a read + * to the same zone could be served. + */ +#define BLK_STS_ZONE_RESOURCE ((__force blk_status_t)14) + /** * blk_path_error - returns true if error may be path related * @error: status the request was completed with @@ -296,6 +308,8 @@ enum req_opf { REQ_OP_ZONE_CLOSE = 11, /* Transition a zone to full */ REQ_OP_ZONE_FINISH = 12, + /* write data at the current zone write pointer */ + REQ_OP_ZONE_APPEND = 13, /* SCSI passthrough using struct scsi_request */ REQ_OP_SCSI_IN = 32, diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index d736acf7f564..5647c78bb876 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -332,6 +332,7 @@ struct queue_limits { unsigned int max_hw_discard_sectors; unsigned int max_write_same_sectors; unsigned int max_write_zeroes_sectors; + unsigned int max_zone_append_sectors; unsigned int discard_granularity; unsigned int discard_alignment; @@ -750,6 +751,9 @@ static inline bool rq_mergeable(struct request *rq) if (req_op(rq) == REQ_OP_WRITE_ZEROES) return false; + if (req_op(rq) == REQ_OP_ZONE_APPEND) + return false; + if (rq->cmd_flags & REQ_NOMERGE_FLAGS) return false; if (rq->rq_flags & RQF_NOMERGE_FLAGS) @@ -1084,6 +1088,8 @@ extern void blk_queue_max_write_same_sectors(struct request_queue *q, extern void blk_queue_max_write_zeroes_sectors(struct request_queue *q, unsigned int max_write_same_sectors); extern void blk_queue_logical_block_size(struct request_queue *, unsigned int); +extern void blk_queue_max_zone_append_sectors(struct request_queue *q, + unsigned int max_zone_append_sectors); extern void blk_queue_physical_block_size(struct request_queue *, unsigned int); extern void blk_queue_alignment_offset(struct request_queue *q, unsigned int alignment); @@ -1301,6 +1307,11 @@ static inline unsigned int queue_max_segment_size(const struct request_queue *q) return q->limits.max_segment_size; } +static inline unsigned int queue_max_zone_append_sectors(const struct request_queue *q) +{ + return q->limits.max_zone_append_sectors; +} + static inline unsigned queue_logical_block_size(const struct request_queue *q) { int retval = 512; -- cgit v1.2.3 From 1392d37018d4f68c5bb2c98dae9a018b73926865 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Tue, 12 May 2020 17:55:48 +0900 Subject: block: introduce blk_req_zone_write_trylock Introduce blk_req_zone_write_trylock(), which either grabs the write-lock for a sequential zone or returns false, if the zone is already locked. Signed-off-by: Johannes Thumshirn Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Signed-off-by: Jens Axboe --- block/blk-zoned.c | 14 ++++++++++++++ include/linux/blkdev.h | 1 + 2 files changed, 15 insertions(+) (limited to 'block') diff --git a/block/blk-zoned.c b/block/blk-zoned.c index f87956e0dcaf..c822cfa7a102 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -82,6 +82,20 @@ bool blk_req_needs_zone_write_lock(struct request *rq) } EXPORT_SYMBOL_GPL(blk_req_needs_zone_write_lock); +bool blk_req_zone_write_trylock(struct request *rq) +{ + unsigned int zno = blk_rq_zone_no(rq); + + if (test_and_set_bit(zno, rq->q->seq_zones_wlock)) + return false; + + WARN_ON_ONCE(rq->rq_flags & RQF_ZONE_WRITE_LOCKED); + rq->rq_flags |= RQF_ZONE_WRITE_LOCKED; + + return true; +} +EXPORT_SYMBOL_GPL(blk_req_zone_write_trylock); + void __blk_req_zone_write_lock(struct request *rq) { if (WARN_ON_ONCE(test_and_set_bit(blk_rq_zone_no(rq), diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 5647c78bb876..73f4f4f1df92 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1738,6 +1738,7 @@ extern int bdev_write_page(struct block_device *, sector_t, struct page *, #ifdef CONFIG_BLK_DEV_ZONED bool blk_req_needs_zone_write_lock(struct request *rq); +bool blk_req_zone_write_trylock(struct request *rq); void __blk_req_zone_write_lock(struct request *rq); void __blk_req_zone_write_unlock(struct request *rq); -- cgit v1.2.3 From e732671aa5f67232cf760666a15242dead003362 Mon Sep 17 00:00:00 2001 From: Damien Le Moal Date: Tue, 12 May 2020 17:55:49 +0900 Subject: block: Modify revalidate zones Modify the interface of blk_revalidate_disk_zones() to add an optional driver callback function that a driver can use to extend processing done during zone revalidation. The callback, if defined, is executed with the device request queue frozen, after all zones have been inspected. Signed-off-by: Damien Le Moal Signed-off-by: Johannes Thumshirn Reviewed-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Martin K. Petersen Signed-off-by: Jens Axboe --- block/blk-zoned.c | 9 ++++++++- drivers/block/null_blk_zoned.c | 2 +- include/linux/blkdev.h | 3 ++- 3 files changed, 11 insertions(+), 3 deletions(-) (limited to 'block') diff --git a/block/blk-zoned.c b/block/blk-zoned.c index c822cfa7a102..23831fa8701d 100644 --- a/block/blk-zoned.c +++ b/block/blk-zoned.c @@ -471,14 +471,19 @@ static int blk_revalidate_zone_cb(struct blk_zone *zone, unsigned int idx, /** * blk_revalidate_disk_zones - (re)allocate and initialize zone bitmaps * @disk: Target disk + * @update_driver_data: Callback to update driver data on the frozen disk * * Helper function for low-level device drivers to (re) allocate and initialize * a disk request queue zone bitmaps. This functions should normally be called * within the disk ->revalidate method for blk-mq based drivers. For BIO based * drivers only q->nr_zones needs to be updated so that the sysfs exposed value * is correct. + * If the @update_driver_data callback function is not NULL, the callback is + * executed with the device request queue frozen after all zones have been + * checked. */ -int blk_revalidate_disk_zones(struct gendisk *disk) +int blk_revalidate_disk_zones(struct gendisk *disk, + void (*update_driver_data)(struct gendisk *disk)) { struct request_queue *q = disk->queue; struct blk_revalidate_zone_args args = { @@ -512,6 +517,8 @@ int blk_revalidate_disk_zones(struct gendisk *disk) q->nr_zones = args.nr_zones; swap(q->seq_zones_wlock, args.seq_zones_wlock); swap(q->conv_zones_bitmap, args.conv_zones_bitmap); + if (update_driver_data) + update_driver_data(disk); ret = 0; } else { pr_warn("%s: failed to revalidate zones\n", disk->disk_name); diff --git a/drivers/block/null_blk_zoned.c b/drivers/block/null_blk_zoned.c index 9e4bcdad1a80..46641df2e58e 100644 --- a/drivers/block/null_blk_zoned.c +++ b/drivers/block/null_blk_zoned.c @@ -73,7 +73,7 @@ int null_register_zoned_dev(struct nullb *nullb) struct request_queue *q = nullb->q; if (queue_is_mq(q)) - return blk_revalidate_disk_zones(nullb->disk); + return blk_revalidate_disk_zones(nullb->disk, NULL); blk_queue_chunk_sectors(q, nullb->dev->zone_size_sects); q->nr_zones = blkdev_nr_zones(nullb->disk); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 73f4f4f1df92..5360696d85ff 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -358,7 +358,8 @@ unsigned int blkdev_nr_zones(struct gendisk *disk); extern int blkdev_zone_mgmt(struct block_device *bdev, enum req_opf op, sector_t sectors, sector_t nr_sectors, gfp_t gfp_mask); -extern int blk_revalidate_disk_zones(struct gendisk *disk); +int blk_revalidate_disk_zones(struct gendisk *disk, + void (*update_driver_data)(struct gendisk *disk)); extern int blkdev_report_zones_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg); -- cgit v1.2.3 From 29b2a3aa296711cfdadafbf627c2d9a388fc84ee Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Tue, 12 May 2020 17:55:53 +0900 Subject: block: export bio_release_pages and bio_iov_iter_get_pages Export bio_release_pages and bio_iov_iter_get_pages, so they can be used from modular code. Signed-off-by: Johannes Thumshirn Reviewed-by: Martin K. Petersen Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/bio.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index 3aa3c4ce2e5e..e4c46e2bd5ba 100644 --- a/block/bio.c +++ b/block/bio.c @@ -951,6 +951,7 @@ void bio_release_pages(struct bio *bio, bool mark_dirty) put_page(bvec->bv_page); } } +EXPORT_SYMBOL_GPL(bio_release_pages); static int __bio_iov_bvec_add_pages(struct bio *bio, struct iov_iter *iter) { @@ -1114,6 +1115,7 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) bio_set_flag(bio, BIO_NO_PAGE_REF); return bio->bi_vcnt ? 0 : ret; } +EXPORT_SYMBOL_GPL(bio_iov_iter_get_pages); static void submit_bio_wait_endio(struct bio *bio) { -- cgit v1.2.3 From 71ac860af824ce9ebbbe8de20044e777c0fc33b9 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Thu, 14 May 2020 16:45:09 +0800 Subject: block: move blk_io_schedule() out of header file blk_io_schedule() isn't called from performance sensitive code path, and it is easier to maintain by exporting it as symbol. Also blk_io_schedule() is only called by CONFIG_BLOCK code, so it is safe to do this way. Meantime fixes build failure when CONFIG_BLOCK is off. Cc: Christoph Hellwig Fixes: e6249cdd46e4 ("block: add blk_io_schedule() for avoiding task hung in sync dio") Reported-by: Satya Tangirala Tested-by: Satya Tangirala Signed-off-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-core.c | 13 +++++++++++++ include/linux/blkdev.h | 14 ++------------ 2 files changed, 15 insertions(+), 12 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index cf5b2163edfe..7c1587b45427 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -38,6 +38,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include @@ -1812,6 +1813,18 @@ void blk_finish_plug(struct blk_plug *plug) } EXPORT_SYMBOL(blk_finish_plug); +void blk_io_schedule(void) +{ + /* Prevent hang_check timer from firing at us during very long I/O */ + unsigned long timeout = sysctl_hung_task_timeout_secs * HZ / 2; + + if (timeout) + io_schedule_timeout(timeout); + else + io_schedule(); +} +EXPORT_SYMBOL_GPL(blk_io_schedule); + int __init blk_dev_init(void) { BUILD_BUG_ON(REQ_OP_LAST >= (1 << REQ_OP_BITS)); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 5360696d85ff..f9e4b21b051b 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -27,7 +27,6 @@ #include #include #include -#include struct module; struct scsi_ioctl_command; @@ -1221,6 +1220,8 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk) !list_empty(&plug->cb_list)); } +extern void blk_io_schedule(void); + extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, struct page *page); @@ -1851,15 +1852,4 @@ static inline void blk_wake_io_task(struct task_struct *waiter) wake_up_process(waiter); } -static inline void blk_io_schedule(void) -{ - /* Prevent hang_check timer from firing at us during very long I/O */ - unsigned long timeout = sysctl_hung_task_timeout_secs * HZ / 2; - - if (timeout) - io_schedule_timeout(timeout); - else - io_schedule(); -} - #endif -- cgit v1.2.3 From 81ca627a933063fa63a6d4c66425de822a2ab7f5 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 14 Oct 2019 17:18:11 -0700 Subject: iocost: don't let vrate run wild while there's no saturation signal When the QoS targets are met and nothing is being throttled, there's no way to tell how saturated the underlying device is - it could be almost entirely idle, at the cusp of saturation or anywhere inbetween. Given that there's no information, it's best to keep vrate as-is in this state. Before 7cd806a9a953 ("iocost: improve nr_lagging handling"), this was the case - if the device isn't missing QoS targets and nothing is being throttled, busy_level was reset to zero. While fixing nr_lagging handling, 7cd806a9a953 ("iocost: improve nr_lagging handling") broke this. Now, while the device is hitting QoS targets and nothing is being throttled, vrate keeps getting adjusted according to the existing busy_level. This led to vrate keeping climing till it hits max when there's an IO issuer with limited request concurrency if the vrate started low. vrate starts getting adjusted upwards until the issuer can issue IOs w/o being throttled. From then on, QoS targets keeps getting met and nothing on the system needs throttling and vrate keeps getting increased due to the existing busy_level. This patch makes the following changes to the busy_level logic. * Reset busy_level if nr_shortages is zero to avoid the above scenario. * Make non-zero nr_lagging block lowering nr_level but still clear positive busy_level if there's clear non-saturation signal - QoS targets are met and nr_shortages is non-zero. nr_lagging's role is preventing adjusting vrate upwards while there are long-running commands and it shouldn't keep busy_level positive while there's clear non-saturation signal. * Restructure code for clarity and add comments. Signed-off-by: Tejun Heo Reported-by: Andy Newell Fixes: 7cd806a9a953 ("iocost: improve nr_lagging handling") Signed-off-by: Jens Axboe --- block/blk-iocost.c | 28 ++++++++++++++++++++++++---- 1 file changed, 24 insertions(+), 4 deletions(-) (limited to 'block') diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 12eefb3d113f..8ac4aad66ebc 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -1539,19 +1539,39 @@ skip_surplus_transfers: if (rq_wait_pct > RQ_WAIT_BUSY_PCT || missed_ppm[READ] > ppm_rthr || missed_ppm[WRITE] > ppm_wthr) { + /* clearly missing QoS targets, slow down vrate */ ioc->busy_level = max(ioc->busy_level, 0); ioc->busy_level++; } else if (rq_wait_pct <= RQ_WAIT_BUSY_PCT * UNBUSY_THR_PCT / 100 && missed_ppm[READ] <= ppm_rthr * UNBUSY_THR_PCT / 100 && missed_ppm[WRITE] <= ppm_wthr * UNBUSY_THR_PCT / 100) { - /* take action iff there is contention */ - if (nr_shortages && !nr_lagging) { + /* QoS targets are being met with >25% margin */ + if (nr_shortages) { + /* + * We're throttling while the device has spare + * capacity. If vrate was being slowed down, stop. + */ ioc->busy_level = min(ioc->busy_level, 0); - /* redistribute surpluses first */ - if (!nr_surpluses) + + /* + * If there are IOs spanning multiple periods, wait + * them out before pushing the device harder. If + * there are surpluses, let redistribution work it + * out first. + */ + if (!nr_lagging && !nr_surpluses) ioc->busy_level--; + } else { + /* + * Nobody is being throttled and the users aren't + * issuing enough IOs to saturate the device. We + * simply don't know how close the device is to + * saturation. Coast. + */ + ioc->busy_level = 0; } } else { + /* inside the hysterisis margin, we're good */ ioc->busy_level = 0; } -- cgit v1.2.3 From 1b2628397058ebce7277480960b29c788138de90 Mon Sep 17 00:00:00 2001 From: Satya Tangirala Date: Thu, 14 May 2020 00:37:17 +0000 Subject: block: Keyslot Manager for Inline Encryption Inline Encryption hardware allows software to specify an encryption context (an encryption key, crypto algorithm, data unit num, data unit size) along with a data transfer request to a storage device, and the inline encryption hardware will use that context to en/decrypt the data. The inline encryption hardware is part of the storage device, and it conceptually sits on the data path between system memory and the storage device. Inline Encryption hardware implementations often function around the concept of "keyslots". These implementations often have a limited number of "keyslots", each of which can hold a key (we say that a key can be "programmed" into a keyslot). Requests made to the storage device may have a keyslot and a data unit number associated with them, and the inline encryption hardware will en/decrypt the data in the requests using the key programmed into that associated keyslot and the data unit number specified with the request. As keyslots are limited, and programming keys may be expensive in many implementations, and multiple requests may use exactly the same encryption contexts, we introduce a Keyslot Manager to efficiently manage keyslots. We also introduce a blk_crypto_key, which will represent the key that's programmed into keyslots managed by keyslot managers. The keyslot manager also functions as the interface that upper layers will use to program keys into inline encryption hardware. For more information on the Keyslot Manager, refer to documentation found in block/keyslot-manager.c and linux/keyslot-manager.h. Co-developed-by: Eric Biggers Signed-off-by: Eric Biggers Signed-off-by: Satya Tangirala Reviewed-by: Eric Biggers Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/Kconfig | 7 + block/Makefile | 1 + block/keyslot-manager.c | 378 ++++++++++++++++++++++++++++++++++++++++ include/linux/blk-crypto.h | 52 ++++++ include/linux/blkdev.h | 6 + include/linux/keyslot-manager.h | 106 +++++++++++ 6 files changed, 550 insertions(+) create mode 100644 block/keyslot-manager.c create mode 100644 include/linux/blk-crypto.h create mode 100644 include/linux/keyslot-manager.h (limited to 'block') diff --git a/block/Kconfig b/block/Kconfig index 41cb34b0fcd1..f8870c316a03 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -186,6 +186,13 @@ config BLK_SED_OPAL Enabling this option enables users to setup/unlock/lock Locking ranges for SED devices using the Opal protocol. +config BLK_INLINE_ENCRYPTION + bool "Enable inline encryption support in block layer" + help + Build the blk-crypto subsystem. Enabling this lets the + block layer handle encryption, so users can take + advantage of inline encryption hardware if present. + menu "Partition Types" source "block/partitions/Kconfig" diff --git a/block/Makefile b/block/Makefile index 206b96e9387f..fc963e4676b0 100644 --- a/block/Makefile +++ b/block/Makefile @@ -36,3 +36,4 @@ obj-$(CONFIG_BLK_DEBUG_FS) += blk-mq-debugfs.o obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o obj-$(CONFIG_BLK_SED_OPAL) += sed-opal.o obj-$(CONFIG_BLK_PM) += blk-pm.o +obj-$(CONFIG_BLK_INLINE_ENCRYPTION) += keyslot-manager.o diff --git a/block/keyslot-manager.c b/block/keyslot-manager.c new file mode 100644 index 000000000000..fcd3fd469d7c --- /dev/null +++ b/block/keyslot-manager.c @@ -0,0 +1,378 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Google LLC + */ + +/** + * DOC: The Keyslot Manager + * + * Many devices with inline encryption support have a limited number of "slots" + * into which encryption contexts may be programmed, and requests can be tagged + * with a slot number to specify the key to use for en/decryption. + * + * As the number of slots is limited, and programming keys is expensive on + * many inline encryption hardware, we don't want to program the same key into + * multiple slots - if multiple requests are using the same key, we want to + * program just one slot with that key and use that slot for all requests. + * + * The keyslot manager manages these keyslots appropriately, and also acts as + * an abstraction between the inline encryption hardware and the upper layers. + * + * Lower layer devices will set up a keyslot manager in their request queue + * and tell it how to perform device specific operations like programming/ + * evicting keys from keyslots. + * + * Upper layers will call blk_ksm_get_slot_for_key() to program a + * key into some slot in the inline encryption hardware. + */ +#include +#include +#include +#include +#include +#include + +struct blk_ksm_keyslot { + atomic_t slot_refs; + struct list_head idle_slot_node; + struct hlist_node hash_node; + const struct blk_crypto_key *key; + struct blk_keyslot_manager *ksm; +}; + +static inline void blk_ksm_hw_enter(struct blk_keyslot_manager *ksm) +{ + /* + * Calling into the driver requires ksm->lock held and the device + * resumed. But we must resume the device first, since that can acquire + * and release ksm->lock via blk_ksm_reprogram_all_keys(). + */ + if (ksm->dev) + pm_runtime_get_sync(ksm->dev); + down_write(&ksm->lock); +} + +static inline void blk_ksm_hw_exit(struct blk_keyslot_manager *ksm) +{ + up_write(&ksm->lock); + if (ksm->dev) + pm_runtime_put_sync(ksm->dev); +} + +/** + * blk_ksm_init() - Initialize a keyslot manager + * @ksm: The keyslot_manager to initialize. + * @num_slots: The number of key slots to manage. + * + * Allocate memory for keyslots and initialize a keyslot manager. Called by + * e.g. storage drivers to set up a keyslot manager in their request_queue. + * + * Return: 0 on success, or else a negative error code. + */ +int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots) +{ + unsigned int slot; + unsigned int i; + unsigned int slot_hashtable_size; + + memset(ksm, 0, sizeof(*ksm)); + + if (num_slots == 0) + return -EINVAL; + + ksm->slots = kvcalloc(num_slots, sizeof(ksm->slots[0]), GFP_KERNEL); + if (!ksm->slots) + return -ENOMEM; + + ksm->num_slots = num_slots; + + init_rwsem(&ksm->lock); + + init_waitqueue_head(&ksm->idle_slots_wait_queue); + INIT_LIST_HEAD(&ksm->idle_slots); + + for (slot = 0; slot < num_slots; slot++) { + ksm->slots[slot].ksm = ksm; + list_add_tail(&ksm->slots[slot].idle_slot_node, + &ksm->idle_slots); + } + + spin_lock_init(&ksm->idle_slots_lock); + + slot_hashtable_size = roundup_pow_of_two(num_slots); + ksm->log_slot_ht_size = ilog2(slot_hashtable_size); + ksm->slot_hashtable = kvmalloc_array(slot_hashtable_size, + sizeof(ksm->slot_hashtable[0]), + GFP_KERNEL); + if (!ksm->slot_hashtable) + goto err_destroy_ksm; + for (i = 0; i < slot_hashtable_size; i++) + INIT_HLIST_HEAD(&ksm->slot_hashtable[i]); + + return 0; + +err_destroy_ksm: + blk_ksm_destroy(ksm); + return -ENOMEM; +} +EXPORT_SYMBOL_GPL(blk_ksm_init); + +static inline struct hlist_head * +blk_ksm_hash_bucket_for_key(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key) +{ + return &ksm->slot_hashtable[hash_ptr(key, ksm->log_slot_ht_size)]; +} + +static void blk_ksm_remove_slot_from_lru_list(struct blk_ksm_keyslot *slot) +{ + struct blk_keyslot_manager *ksm = slot->ksm; + unsigned long flags; + + spin_lock_irqsave(&ksm->idle_slots_lock, flags); + list_del(&slot->idle_slot_node); + spin_unlock_irqrestore(&ksm->idle_slots_lock, flags); +} + +static struct blk_ksm_keyslot *blk_ksm_find_keyslot( + struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key) +{ + const struct hlist_head *head = blk_ksm_hash_bucket_for_key(ksm, key); + struct blk_ksm_keyslot *slotp; + + hlist_for_each_entry(slotp, head, hash_node) { + if (slotp->key == key) + return slotp; + } + return NULL; +} + +static struct blk_ksm_keyslot *blk_ksm_find_and_grab_keyslot( + struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key) +{ + struct blk_ksm_keyslot *slot; + + slot = blk_ksm_find_keyslot(ksm, key); + if (!slot) + return NULL; + if (atomic_inc_return(&slot->slot_refs) == 1) { + /* Took first reference to this slot; remove it from LRU list */ + blk_ksm_remove_slot_from_lru_list(slot); + } + return slot; +} + +unsigned int blk_ksm_get_slot_idx(struct blk_ksm_keyslot *slot) +{ + return slot - slot->ksm->slots; +} +EXPORT_SYMBOL_GPL(blk_ksm_get_slot_idx); + +/** + * blk_ksm_get_slot_for_key() - Program a key into a keyslot. + * @ksm: The keyslot manager to program the key into. + * @key: Pointer to the key object to program, including the raw key, crypto + * mode, and data unit size. + * @slot_ptr: A pointer to return the pointer of the allocated keyslot. + * + * Get a keyslot that's been programmed with the specified key. If one already + * exists, return it with incremented refcount. Otherwise, wait for a keyslot + * to become idle and program it. + * + * Context: Process context. Takes and releases ksm->lock. + * Return: BLK_STS_OK on success (and keyslot is set to the pointer of the + * allocated keyslot), or some other blk_status_t otherwise (and + * keyslot is set to NULL). + */ +blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key, + struct blk_ksm_keyslot **slot_ptr) +{ + struct blk_ksm_keyslot *slot; + int slot_idx; + int err; + + *slot_ptr = NULL; + down_read(&ksm->lock); + slot = blk_ksm_find_and_grab_keyslot(ksm, key); + up_read(&ksm->lock); + if (slot) + goto success; + + for (;;) { + blk_ksm_hw_enter(ksm); + slot = blk_ksm_find_and_grab_keyslot(ksm, key); + if (slot) { + blk_ksm_hw_exit(ksm); + goto success; + } + + /* + * If we're here, that means there wasn't a slot that was + * already programmed with the key. So try to program it. + */ + if (!list_empty(&ksm->idle_slots)) + break; + + blk_ksm_hw_exit(ksm); + wait_event(ksm->idle_slots_wait_queue, + !list_empty(&ksm->idle_slots)); + } + + slot = list_first_entry(&ksm->idle_slots, struct blk_ksm_keyslot, + idle_slot_node); + slot_idx = blk_ksm_get_slot_idx(slot); + + err = ksm->ksm_ll_ops.keyslot_program(ksm, key, slot_idx); + if (err) { + wake_up(&ksm->idle_slots_wait_queue); + blk_ksm_hw_exit(ksm); + return errno_to_blk_status(err); + } + + /* Move this slot to the hash list for the new key. */ + if (slot->key) + hlist_del(&slot->hash_node); + slot->key = key; + hlist_add_head(&slot->hash_node, blk_ksm_hash_bucket_for_key(ksm, key)); + + atomic_set(&slot->slot_refs, 1); + + blk_ksm_remove_slot_from_lru_list(slot); + + blk_ksm_hw_exit(ksm); +success: + *slot_ptr = slot; + return BLK_STS_OK; +} + +/** + * blk_ksm_put_slot() - Release a reference to a slot + * @slot: The keyslot to release the reference of. + * + * Context: Any context. + */ +void blk_ksm_put_slot(struct blk_ksm_keyslot *slot) +{ + struct blk_keyslot_manager *ksm; + unsigned long flags; + + if (!slot) + return; + + ksm = slot->ksm; + + if (atomic_dec_and_lock_irqsave(&slot->slot_refs, + &ksm->idle_slots_lock, flags)) { + list_add_tail(&slot->idle_slot_node, &ksm->idle_slots); + spin_unlock_irqrestore(&ksm->idle_slots_lock, flags); + wake_up(&ksm->idle_slots_wait_queue); + } +} + +/** + * blk_ksm_crypto_cfg_supported() - Find out if a crypto configuration is + * supported by a ksm. + * @ksm: The keyslot manager to check + * @cfg: The crypto configuration to check for. + * + * Checks for crypto_mode/data unit size/dun bytes support. + * + * Return: Whether or not this ksm supports the specified crypto config. + */ +bool blk_ksm_crypto_cfg_supported(struct blk_keyslot_manager *ksm, + const struct blk_crypto_config *cfg) +{ + if (!ksm) + return false; + if (!(ksm->crypto_modes_supported[cfg->crypto_mode] & + cfg->data_unit_size)) + return false; + if (ksm->max_dun_bytes_supported < cfg->dun_bytes) + return false; + return true; +} + +/** + * blk_ksm_evict_key() - Evict a key from the lower layer device. + * @ksm: The keyslot manager to evict from + * @key: The key to evict + * + * Find the keyslot that the specified key was programmed into, and evict that + * slot from the lower layer device. The slot must not be in use by any + * in-flight IO when this function is called. + * + * Context: Process context. Takes and releases ksm->lock. + * Return: 0 on success or if there's no keyslot with the specified key, -EBUSY + * if the keyslot is still in use, or another -errno value on other + * error. + */ +int blk_ksm_evict_key(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key) +{ + struct blk_ksm_keyslot *slot; + int err = 0; + + blk_ksm_hw_enter(ksm); + slot = blk_ksm_find_keyslot(ksm, key); + if (!slot) + goto out_unlock; + + if (WARN_ON_ONCE(atomic_read(&slot->slot_refs) != 0)) { + err = -EBUSY; + goto out_unlock; + } + err = ksm->ksm_ll_ops.keyslot_evict(ksm, key, + blk_ksm_get_slot_idx(slot)); + if (err) + goto out_unlock; + + hlist_del(&slot->hash_node); + slot->key = NULL; + err = 0; +out_unlock: + blk_ksm_hw_exit(ksm); + return err; +} + +/** + * blk_ksm_reprogram_all_keys() - Re-program all keyslots. + * @ksm: The keyslot manager + * + * Re-program all keyslots that are supposed to have a key programmed. This is + * intended only for use by drivers for hardware that loses its keys on reset. + * + * Context: Process context. Takes and releases ksm->lock. + */ +void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm) +{ + unsigned int slot; + + /* This is for device initialization, so don't resume the device */ + down_write(&ksm->lock); + for (slot = 0; slot < ksm->num_slots; slot++) { + const struct blk_crypto_key *key = ksm->slots[slot].key; + int err; + + if (!key) + continue; + + err = ksm->ksm_ll_ops.keyslot_program(ksm, key, slot); + WARN_ON(err); + } + up_write(&ksm->lock); +} +EXPORT_SYMBOL_GPL(blk_ksm_reprogram_all_keys); + +void blk_ksm_destroy(struct blk_keyslot_manager *ksm) +{ + if (!ksm) + return; + kvfree(ksm->slot_hashtable); + memzero_explicit(ksm->slots, sizeof(ksm->slots[0]) * ksm->num_slots); + kvfree(ksm->slots); + memzero_explicit(ksm, sizeof(*ksm)); +} +EXPORT_SYMBOL_GPL(blk_ksm_destroy); diff --git a/include/linux/blk-crypto.h b/include/linux/blk-crypto.h new file mode 100644 index 000000000000..4e77938c3d0e --- /dev/null +++ b/include/linux/blk-crypto.h @@ -0,0 +1,52 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright 2019 Google LLC + */ + +#ifndef __LINUX_BLK_CRYPTO_H +#define __LINUX_BLK_CRYPTO_H + +enum blk_crypto_mode_num { + BLK_ENCRYPTION_MODE_INVALID, + BLK_ENCRYPTION_MODE_AES_256_XTS, + BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV, + BLK_ENCRYPTION_MODE_ADIANTUM, + BLK_ENCRYPTION_MODE_MAX, +}; + +#define BLK_CRYPTO_MAX_KEY_SIZE 64 +/** + * struct blk_crypto_config - an inline encryption key's crypto configuration + * @crypto_mode: encryption algorithm this key is for + * @data_unit_size: the data unit size for all encryption/decryptions with this + * key. This is the size in bytes of each individual plaintext and + * ciphertext. This is always a power of 2. It might be e.g. the + * filesystem block size or the disk sector size. + * @dun_bytes: the maximum number of bytes of DUN used when using this key + */ +struct blk_crypto_config { + enum blk_crypto_mode_num crypto_mode; + unsigned int data_unit_size; + unsigned int dun_bytes; +}; + +/** + * struct blk_crypto_key - an inline encryption key + * @crypto_cfg: the crypto configuration (like crypto_mode, key size) for this + * key + * @data_unit_size_bits: log2 of data_unit_size + * @size: size of this key in bytes (determined by @crypto_cfg.crypto_mode) + * @raw: the raw bytes of this key. Only the first @size bytes are used. + * + * A blk_crypto_key is immutable once created, and many bios can reference it at + * the same time. It must not be freed until all bios using it have completed + * and it has been evicted from all devices on which it may have been used. + */ +struct blk_crypto_key { + struct blk_crypto_config crypto_cfg; + unsigned int data_unit_size_bits; + unsigned int size; + u8 raw[BLK_CRYPTO_MAX_KEY_SIZE]; +}; + +#endif /* __LINUX_BLK_CRYPTO_H */ diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index f9e4b21b051b..354e44eebef9 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -43,6 +43,7 @@ struct pr_ops; struct rq_qos; struct blk_queue_stats; struct blk_stat_callback; +struct blk_keyslot_manager; #define BLKDEV_MIN_RQ 4 #define BLKDEV_MAX_RQ 128 /* Default maximum */ @@ -468,6 +469,11 @@ struct request_queue { unsigned int dma_pad_mask; unsigned int dma_alignment; +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + /* Inline crypto capabilities */ + struct blk_keyslot_manager *ksm; +#endif + unsigned int rq_timeout; int poll_nsec; diff --git a/include/linux/keyslot-manager.h b/include/linux/keyslot-manager.h new file mode 100644 index 000000000000..18f3f5346843 --- /dev/null +++ b/include/linux/keyslot-manager.h @@ -0,0 +1,106 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright 2019 Google LLC + */ + +#ifndef __LINUX_KEYSLOT_MANAGER_H +#define __LINUX_KEYSLOT_MANAGER_H + +#include +#include + +struct blk_keyslot_manager; + +/** + * struct blk_ksm_ll_ops - functions to manage keyslots in hardware + * @keyslot_program: Program the specified key into the specified slot in the + * inline encryption hardware. + * @keyslot_evict: Evict key from the specified keyslot in the hardware. + * The key is provided so that e.g. dm layers can evict + * keys from the devices that they map over. + * Returns 0 on success, -errno otherwise. + * + * This structure should be provided by storage device drivers when they set up + * a keyslot manager - this structure holds the function ptrs that the keyslot + * manager will use to manipulate keyslots in the hardware. + */ +struct blk_ksm_ll_ops { + int (*keyslot_program)(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key, + unsigned int slot); + int (*keyslot_evict)(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key, + unsigned int slot); +}; + +struct blk_keyslot_manager { + /* + * The struct blk_ksm_ll_ops that this keyslot manager will use + * to perform operations like programming and evicting keys on the + * device + */ + struct blk_ksm_ll_ops ksm_ll_ops; + + /* + * The maximum number of bytes supported for specifying the data unit + * number. + */ + unsigned int max_dun_bytes_supported; + + /* + * Array of size BLK_ENCRYPTION_MODE_MAX of bitmasks that represents + * whether a crypto mode and data unit size are supported. The i'th + * bit of crypto_mode_supported[crypto_mode] is set iff a data unit + * size of (1 << i) is supported. We only support data unit sizes + * that are powers of 2. + */ + unsigned int crypto_modes_supported[BLK_ENCRYPTION_MODE_MAX]; + + /* Device for runtime power management (NULL if none) */ + struct device *dev; + + /* Here onwards are *private* fields for internal keyslot manager use */ + + unsigned int num_slots; + + /* Protects programming and evicting keys from the device */ + struct rw_semaphore lock; + + /* List of idle slots, with least recently used slot at front */ + wait_queue_head_t idle_slots_wait_queue; + struct list_head idle_slots; + spinlock_t idle_slots_lock; + + /* + * Hash table which maps struct *blk_crypto_key to keyslots, so that we + * can find a key's keyslot in O(1) time rather than O(num_slots). + * Protected by 'lock'. + */ + struct hlist_head *slot_hashtable; + unsigned int log_slot_ht_size; + + /* Per-keyslot data */ + struct blk_ksm_keyslot *slots; +}; + +int blk_ksm_init(struct blk_keyslot_manager *ksm, unsigned int num_slots); + +blk_status_t blk_ksm_get_slot_for_key(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key, + struct blk_ksm_keyslot **slot_ptr); + +unsigned int blk_ksm_get_slot_idx(struct blk_ksm_keyslot *slot); + +void blk_ksm_put_slot(struct blk_ksm_keyslot *slot); + +bool blk_ksm_crypto_cfg_supported(struct blk_keyslot_manager *ksm, + const struct blk_crypto_config *cfg); + +int blk_ksm_evict_key(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key); + +void blk_ksm_reprogram_all_keys(struct blk_keyslot_manager *ksm); + +void blk_ksm_destroy(struct blk_keyslot_manager *ksm); + +#endif /* __LINUX_KEYSLOT_MANAGER_H */ -- cgit v1.2.3 From a892c8d52c02284076fbbacae6692aa5c5807d11 Mon Sep 17 00:00:00 2001 From: Satya Tangirala Date: Thu, 14 May 2020 00:37:18 +0000 Subject: block: Inline encryption support for blk-mq We must have some way of letting a storage device driver know what encryption context it should use for en/decrypting a request. However, it's the upper layers (like the filesystem/fscrypt) that know about and manages encryption contexts. As such, when the upper layer submits a bio to the block layer, and this bio eventually reaches a device driver with support for inline encryption, the device driver will need to have been told the encryption context for that bio. We want to communicate the encryption context from the upper layer to the storage device along with the bio, when the bio is submitted to the block layer. To do this, we add a struct bio_crypt_ctx to struct bio, which can represent an encryption context (note that we can't use the bi_private field in struct bio to do this because that field does not function to pass information across layers in the storage stack). We also introduce various functions to manipulate the bio_crypt_ctx and make the bio/request merging logic aware of the bio_crypt_ctx. We also make changes to blk-mq to make it handle bios with encryption contexts. blk-mq can merge many bios into the same request. These bios need to have contiguous data unit numbers (the necessary changes to blk-merge are also made to ensure this) - as such, it suffices to keep the data unit number of just the first bio, since that's all a storage driver needs to infer the data unit number to use for each data block in each bio in a request. blk-mq keeps track of the encryption context to be used for all the bios in a request with the request's rq_crypt_ctx. When the first bio is added to an empty request, blk-mq will program the encryption context of that bio into the request_queue's keyslot manager, and store the returned keyslot in the request's rq_crypt_ctx. All the functions to operate on encryption contexts are in blk-crypto.c. Upper layers only need to call bio_crypt_set_ctx with the encryption key, algorithm and data_unit_num; they don't have to worry about getting a keyslot for each encryption context, as blk-mq/blk-crypto handles that. Blk-crypto also makes it possible for request-based layered devices like dm-rq to make use of inline encryption hardware by cloning the rq_crypt_ctx and programming a keyslot in the new request_queue when necessary. Note that any user of the block layer can submit bios with an encryption context, such as filesystems, device-mapper targets, etc. Signed-off-by: Satya Tangirala Reviewed-by: Eric Biggers Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/Makefile | 2 +- block/bio.c | 6 + block/blk-core.c | 27 +++- block/blk-crypto-internal.h | 166 +++++++++++++++++++ block/blk-crypto.c | 376 ++++++++++++++++++++++++++++++++++++++++++++ block/blk-map.c | 1 + block/blk-merge.c | 11 ++ block/blk-mq.c | 13 ++ block/blk.h | 2 + block/bounce.c | 2 + drivers/md/dm.c | 3 + include/linux/blk-crypto.h | 71 +++++++++ include/linux/blk_types.h | 6 + include/linux/blkdev.h | 5 + 14 files changed, 684 insertions(+), 7 deletions(-) create mode 100644 block/blk-crypto-internal.h create mode 100644 block/blk-crypto.c (limited to 'block') diff --git a/block/Makefile b/block/Makefile index fc963e4676b0..3ee88d3e807d 100644 --- a/block/Makefile +++ b/block/Makefile @@ -36,4 +36,4 @@ obj-$(CONFIG_BLK_DEBUG_FS) += blk-mq-debugfs.o obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o obj-$(CONFIG_BLK_SED_OPAL) += sed-opal.o obj-$(CONFIG_BLK_PM) += blk-pm.o -obj-$(CONFIG_BLK_INLINE_ENCRYPTION) += keyslot-manager.o +obj-$(CONFIG_BLK_INLINE_ENCRYPTION) += keyslot-manager.o blk-crypto.o diff --git a/block/bio.c b/block/bio.c index e4c46e2bd5ba..1594804fe8bc 100644 --- a/block/bio.c +++ b/block/bio.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include "blk.h" @@ -237,6 +238,8 @@ void bio_uninit(struct bio *bio) if (bio_integrity(bio)) bio_integrity_free(bio); + + bio_crypt_free_ctx(bio); } EXPORT_SYMBOL(bio_uninit); @@ -708,6 +711,8 @@ struct bio *bio_clone_fast(struct bio *bio, gfp_t gfp_mask, struct bio_set *bs) __bio_clone_fast(b, bio); + bio_crypt_clone(b, bio, gfp_mask); + if (bio_integrity(bio)) { int ret; @@ -1172,6 +1177,7 @@ void bio_advance(struct bio *bio, unsigned bytes) if (bio_integrity(bio)) bio_integrity_advance(bio, bytes); + bio_crypt_advance(bio, bytes); bio_advance_iter(bio, &bio->bi_iter, bytes); } EXPORT_SYMBOL(bio_advance); diff --git a/block/blk-core.c b/block/blk-core.c index 7c1587b45427..1e97f9973523 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -39,6 +39,7 @@ #include #include #include +#include #define CREATE_TRACE_POINTS #include @@ -121,6 +122,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq) rq->start_time_ns = ktime_get_ns(); rq->part = NULL; refcount_set(&rq->ref, 1); + blk_crypto_rq_set_defaults(rq); } EXPORT_SYMBOL(blk_rq_init); @@ -652,6 +654,8 @@ bool bio_attempt_back_merge(struct request *req, struct bio *bio, req->biotail = bio; req->__data_len += bio->bi_iter.bi_size; + bio_crypt_free_ctx(bio); + blk_account_io_start(req, false); return true; } @@ -676,6 +680,8 @@ bool bio_attempt_front_merge(struct request *req, struct bio *bio, req->__sector = bio->bi_iter.bi_sector; req->__data_len += bio->bi_iter.bi_size; + bio_crypt_do_front_merge(req, bio); + blk_account_io_start(req, false); return true; } @@ -1125,10 +1131,12 @@ blk_qc_t generic_make_request(struct bio *bio) /* Create a fresh bio_list for all subordinate requests */ bio_list_on_stack[1] = bio_list_on_stack[0]; bio_list_init(&bio_list_on_stack[0]); - if (q->make_request_fn) - ret = q->make_request_fn(q, bio); - else - ret = blk_mq_make_request(q, bio); + if (blk_crypto_bio_prep(&bio)) { + if (q->make_request_fn) + ret = q->make_request_fn(q, bio); + else + ret = blk_mq_make_request(q, bio); + } blk_queue_exit(q); @@ -1167,7 +1175,7 @@ EXPORT_SYMBOL(generic_make_request); blk_qc_t direct_make_request(struct bio *bio) { struct request_queue *q = bio->bi_disk->queue; - blk_qc_t ret; + blk_qc_t ret = BLK_QC_T_NONE; if (WARN_ON_ONCE(q->make_request_fn)) { bio_io_error(bio); @@ -1177,7 +1185,8 @@ blk_qc_t direct_make_request(struct bio *bio) return BLK_QC_T_NONE; if (unlikely(bio_queue_enter(bio))) return BLK_QC_T_NONE; - ret = blk_mq_make_request(q, bio); + if (blk_crypto_bio_prep(&bio)) + ret = blk_mq_make_request(q, bio); blk_queue_exit(q); return ret; } @@ -1309,6 +1318,9 @@ blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request * should_fail_request(&rq->rq_disk->part0, blk_rq_bytes(rq))) return BLK_STS_IOERR; + if (blk_crypto_insert_cloned_request(rq)) + return BLK_STS_IOERR; + if (blk_queue_io_stat(q)) blk_account_io_start(rq, true); @@ -1673,6 +1685,9 @@ int blk_rq_prep_clone(struct request *rq, struct request *rq_src, rq->nr_phys_segments = rq_src->nr_phys_segments; rq->ioprio = rq_src->ioprio; + if (rq->bio) + blk_crypto_rq_bio_prep(rq, rq->bio, gfp_mask); + return 0; free_and_out: diff --git a/block/blk-crypto-internal.h b/block/blk-crypto-internal.h new file mode 100644 index 000000000000..796f757fe8e9 --- /dev/null +++ b/block/blk-crypto-internal.h @@ -0,0 +1,166 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright 2019 Google LLC + */ + +#ifndef __LINUX_BLK_CRYPTO_INTERNAL_H +#define __LINUX_BLK_CRYPTO_INTERNAL_H + +#include +#include + +/* Represents a crypto mode supported by blk-crypto */ +struct blk_crypto_mode { + unsigned int keysize; /* key size in bytes */ + unsigned int ivsize; /* iv size in bytes */ +}; + +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + +void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], + unsigned int inc); + +bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio); + +bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes, + struct bio_crypt_ctx *bc2); + +static inline bool bio_crypt_ctx_back_mergeable(struct request *req, + struct bio *bio) +{ + return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req), + bio->bi_crypt_context); +} + +static inline bool bio_crypt_ctx_front_mergeable(struct request *req, + struct bio *bio) +{ + return bio_crypt_ctx_mergeable(bio->bi_crypt_context, + bio->bi_iter.bi_size, req->crypt_ctx); +} + +static inline bool bio_crypt_ctx_merge_rq(struct request *req, + struct request *next) +{ + return bio_crypt_ctx_mergeable(req->crypt_ctx, blk_rq_bytes(req), + next->crypt_ctx); +} + +static inline void blk_crypto_rq_set_defaults(struct request *rq) +{ + rq->crypt_ctx = NULL; + rq->crypt_keyslot = NULL; +} + +static inline bool blk_crypto_rq_is_encrypted(struct request *rq) +{ + return rq->crypt_ctx; +} + +#else /* CONFIG_BLK_INLINE_ENCRYPTION */ + +static inline bool bio_crypt_rq_ctx_compatible(struct request *rq, + struct bio *bio) +{ + return true; +} + +static inline bool bio_crypt_ctx_front_mergeable(struct request *req, + struct bio *bio) +{ + return true; +} + +static inline bool bio_crypt_ctx_back_mergeable(struct request *req, + struct bio *bio) +{ + return true; +} + +static inline bool bio_crypt_ctx_merge_rq(struct request *req, + struct request *next) +{ + return true; +} + +static inline void blk_crypto_rq_set_defaults(struct request *rq) { } + +static inline bool blk_crypto_rq_is_encrypted(struct request *rq) +{ + return false; +} + +#endif /* CONFIG_BLK_INLINE_ENCRYPTION */ + +void __bio_crypt_advance(struct bio *bio, unsigned int bytes); +static inline void bio_crypt_advance(struct bio *bio, unsigned int bytes) +{ + if (bio_has_crypt_ctx(bio)) + __bio_crypt_advance(bio, bytes); +} + +void __bio_crypt_free_ctx(struct bio *bio); +static inline void bio_crypt_free_ctx(struct bio *bio) +{ + if (bio_has_crypt_ctx(bio)) + __bio_crypt_free_ctx(bio); +} + +static inline void bio_crypt_do_front_merge(struct request *rq, + struct bio *bio) +{ +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + if (bio_has_crypt_ctx(bio)) + memcpy(rq->crypt_ctx->bc_dun, bio->bi_crypt_context->bc_dun, + sizeof(rq->crypt_ctx->bc_dun)); +#endif +} + +bool __blk_crypto_bio_prep(struct bio **bio_ptr); +static inline bool blk_crypto_bio_prep(struct bio **bio_ptr) +{ + if (bio_has_crypt_ctx(*bio_ptr)) + return __blk_crypto_bio_prep(bio_ptr); + return true; +} + +blk_status_t __blk_crypto_init_request(struct request *rq); +static inline blk_status_t blk_crypto_init_request(struct request *rq) +{ + if (blk_crypto_rq_is_encrypted(rq)) + return __blk_crypto_init_request(rq); + return BLK_STS_OK; +} + +void __blk_crypto_free_request(struct request *rq); +static inline void blk_crypto_free_request(struct request *rq) +{ + if (blk_crypto_rq_is_encrypted(rq)) + __blk_crypto_free_request(rq); +} + +void __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, + gfp_t gfp_mask); +static inline void blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, + gfp_t gfp_mask) +{ + if (bio_has_crypt_ctx(bio)) + __blk_crypto_rq_bio_prep(rq, bio, gfp_mask); +} + +/** + * blk_crypto_insert_cloned_request - Prepare a cloned request to be inserted + * into a request queue. + * @rq: the request being queued + * + * Return: BLK_STS_OK on success, nonzero on error. + */ +static inline blk_status_t blk_crypto_insert_cloned_request(struct request *rq) +{ + + if (blk_crypto_rq_is_encrypted(rq)) + return blk_crypto_init_request(rq); + return BLK_STS_OK; +} + +#endif /* __LINUX_BLK_CRYPTO_INTERNAL_H */ diff --git a/block/blk-crypto.c b/block/blk-crypto.c new file mode 100644 index 000000000000..25b981257f5f --- /dev/null +++ b/block/blk-crypto.c @@ -0,0 +1,376 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Google LLC + */ + +/* + * Refer to Documentation/block/inline-encryption.rst for detailed explanation. + */ + +#define pr_fmt(fmt) "blk-crypto: " fmt + +#include +#include +#include +#include +#include + +#include "blk-crypto-internal.h" + +const struct blk_crypto_mode blk_crypto_modes[] = { + [BLK_ENCRYPTION_MODE_AES_256_XTS] = { + .keysize = 64, + .ivsize = 16, + }, + [BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV] = { + .keysize = 16, + .ivsize = 16, + }, + [BLK_ENCRYPTION_MODE_ADIANTUM] = { + .keysize = 32, + .ivsize = 32, + }, +}; + +/* + * This number needs to be at least (the number of threads doing IO + * concurrently) * (maximum recursive depth of a bio), so that we don't + * deadlock on crypt_ctx allocations. The default is chosen to be the same + * as the default number of post read contexts in both EXT4 and F2FS. + */ +static int num_prealloc_crypt_ctxs = 128; + +module_param(num_prealloc_crypt_ctxs, int, 0444); +MODULE_PARM_DESC(num_prealloc_crypt_ctxs, + "Number of bio crypto contexts to preallocate"); + +static struct kmem_cache *bio_crypt_ctx_cache; +static mempool_t *bio_crypt_ctx_pool; + +static int __init bio_crypt_ctx_init(void) +{ + size_t i; + + bio_crypt_ctx_cache = KMEM_CACHE(bio_crypt_ctx, 0); + if (!bio_crypt_ctx_cache) + goto out_no_mem; + + bio_crypt_ctx_pool = mempool_create_slab_pool(num_prealloc_crypt_ctxs, + bio_crypt_ctx_cache); + if (!bio_crypt_ctx_pool) + goto out_no_mem; + + /* This is assumed in various places. */ + BUILD_BUG_ON(BLK_ENCRYPTION_MODE_INVALID != 0); + + /* Sanity check that no algorithm exceeds the defined limits. */ + for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++) { + BUG_ON(blk_crypto_modes[i].keysize > BLK_CRYPTO_MAX_KEY_SIZE); + BUG_ON(blk_crypto_modes[i].ivsize > BLK_CRYPTO_MAX_IV_SIZE); + } + + return 0; +out_no_mem: + panic("Failed to allocate mem for bio crypt ctxs\n"); +} +subsys_initcall(bio_crypt_ctx_init); + +void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key, + const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], gfp_t gfp_mask) +{ + struct bio_crypt_ctx *bc = mempool_alloc(bio_crypt_ctx_pool, gfp_mask); + + bc->bc_key = key; + memcpy(bc->bc_dun, dun, sizeof(bc->bc_dun)); + + bio->bi_crypt_context = bc; +} + +void __bio_crypt_free_ctx(struct bio *bio) +{ + mempool_free(bio->bi_crypt_context, bio_crypt_ctx_pool); + bio->bi_crypt_context = NULL; +} + +void __bio_crypt_clone(struct bio *dst, struct bio *src, gfp_t gfp_mask) +{ + dst->bi_crypt_context = mempool_alloc(bio_crypt_ctx_pool, gfp_mask); + *dst->bi_crypt_context = *src->bi_crypt_context; +} +EXPORT_SYMBOL_GPL(__bio_crypt_clone); + +/* Increments @dun by @inc, treating @dun as a multi-limb integer. */ +void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], + unsigned int inc) +{ + int i; + + for (i = 0; inc && i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) { + dun[i] += inc; + /* + * If the addition in this limb overflowed, then we need to + * carry 1 into the next limb. Else the carry is 0. + */ + if (dun[i] < inc) + inc = 1; + else + inc = 0; + } +} + +void __bio_crypt_advance(struct bio *bio, unsigned int bytes) +{ + struct bio_crypt_ctx *bc = bio->bi_crypt_context; + + bio_crypt_dun_increment(bc->bc_dun, + bytes >> bc->bc_key->data_unit_size_bits); +} + +/* + * Returns true if @bc->bc_dun plus @bytes converted to data units is equal to + * @next_dun, treating the DUNs as multi-limb integers. + */ +bool bio_crypt_dun_is_contiguous(const struct bio_crypt_ctx *bc, + unsigned int bytes, + const u64 next_dun[BLK_CRYPTO_DUN_ARRAY_SIZE]) +{ + int i; + unsigned int carry = bytes >> bc->bc_key->data_unit_size_bits; + + for (i = 0; i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) { + if (bc->bc_dun[i] + carry != next_dun[i]) + return false; + /* + * If the addition in this limb overflowed, then we need to + * carry 1 into the next limb. Else the carry is 0. + */ + if ((bc->bc_dun[i] + carry) < carry) + carry = 1; + else + carry = 0; + } + + /* If the DUN wrapped through 0, don't treat it as contiguous. */ + return carry == 0; +} + +/* + * Checks that two bio crypt contexts are compatible - i.e. that + * they are mergeable except for data_unit_num continuity. + */ +static bool bio_crypt_ctx_compatible(struct bio_crypt_ctx *bc1, + struct bio_crypt_ctx *bc2) +{ + if (!bc1) + return !bc2; + + return bc2 && bc1->bc_key == bc2->bc_key; +} + +bool bio_crypt_rq_ctx_compatible(struct request *rq, struct bio *bio) +{ + return bio_crypt_ctx_compatible(rq->crypt_ctx, bio->bi_crypt_context); +} + +/* + * Checks that two bio crypt contexts are compatible, and also + * that their data_unit_nums are continuous (and can hence be merged) + * in the order @bc1 followed by @bc2. + */ +bool bio_crypt_ctx_mergeable(struct bio_crypt_ctx *bc1, unsigned int bc1_bytes, + struct bio_crypt_ctx *bc2) +{ + if (!bio_crypt_ctx_compatible(bc1, bc2)) + return false; + + return !bc1 || bio_crypt_dun_is_contiguous(bc1, bc1_bytes, bc2->bc_dun); +} + +/* Check that all I/O segments are data unit aligned. */ +static bool bio_crypt_check_alignment(struct bio *bio) +{ + const unsigned int data_unit_size = + bio->bi_crypt_context->bc_key->crypto_cfg.data_unit_size; + struct bvec_iter iter; + struct bio_vec bv; + + bio_for_each_segment(bv, bio, iter) { + if (!IS_ALIGNED(bv.bv_len | bv.bv_offset, data_unit_size)) + return false; + } + + return true; +} + +blk_status_t __blk_crypto_init_request(struct request *rq) +{ + return blk_ksm_get_slot_for_key(rq->q->ksm, rq->crypt_ctx->bc_key, + &rq->crypt_keyslot); +} + +/** + * __blk_crypto_free_request - Uninitialize the crypto fields of a request. + * + * @rq: The request whose crypto fields to uninitialize. + * + * Completely uninitializes the crypto fields of a request. If a keyslot has + * been programmed into some inline encryption hardware, that keyslot is + * released. The rq->crypt_ctx is also freed. + */ +void __blk_crypto_free_request(struct request *rq) +{ + blk_ksm_put_slot(rq->crypt_keyslot); + mempool_free(rq->crypt_ctx, bio_crypt_ctx_pool); + blk_crypto_rq_set_defaults(rq); +} + +/** + * __blk_crypto_bio_prep - Prepare bio for inline encryption + * + * @bio_ptr: pointer to original bio pointer + * + * Succeeds if the bio doesn't have inline encryption enabled or if the bio + * crypt context provided for the bio is supported by the underlying device's + * inline encryption hardware. Ends the bio with error otherwise. + * + * Caller must ensure bio has bio_crypt_ctx. + * + * Return: true on success; false on error (and bio->bi_status will be set + * appropriately, and bio_endio() will have been called so bio + * submission should abort). + */ +bool __blk_crypto_bio_prep(struct bio **bio_ptr) +{ + struct bio *bio = *bio_ptr; + const struct blk_crypto_key *bc_key = bio->bi_crypt_context->bc_key; + blk_status_t blk_st = BLK_STS_IOERR; + + /* Error if bio has no data. */ + if (WARN_ON_ONCE(!bio_has_data(bio))) + goto fail; + + if (!bio_crypt_check_alignment(bio)) + goto fail; + + /* + * Success if device supports the encryption context. + */ + if (!blk_ksm_crypto_cfg_supported(bio->bi_disk->queue->ksm, + &bc_key->crypto_cfg)) { + blk_st = BLK_STS_NOTSUPP; + goto fail; + } + + return true; +fail: + (*bio_ptr)->bi_status = blk_st; + bio_endio(*bio_ptr); + return false; +} + +/** + * __blk_crypto_rq_bio_prep - Prepare a request's crypt_ctx when its first bio + * is inserted + * + * @rq: The request to prepare + * @bio: The first bio being inserted into the request + * @gfp_mask: gfp mask + */ +void __blk_crypto_rq_bio_prep(struct request *rq, struct bio *bio, + gfp_t gfp_mask) +{ + if (!rq->crypt_ctx) + rq->crypt_ctx = mempool_alloc(bio_crypt_ctx_pool, gfp_mask); + *rq->crypt_ctx = *bio->bi_crypt_context; +} + +/** + * blk_crypto_init_key() - Prepare a key for use with blk-crypto + * @blk_key: Pointer to the blk_crypto_key to initialize. + * @raw_key: Pointer to the raw key. Must be the correct length for the chosen + * @crypto_mode; see blk_crypto_modes[]. + * @crypto_mode: identifier for the encryption algorithm to use + * @dun_bytes: number of bytes that will be used to specify the DUN when this + * key is used + * @data_unit_size: the data unit size to use for en/decryption + * + * Return: 0 on success, -errno on failure. The caller is responsible for + * zeroizing both blk_key and raw_key when done with them. + */ +int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key, + enum blk_crypto_mode_num crypto_mode, + unsigned int dun_bytes, + unsigned int data_unit_size) +{ + const struct blk_crypto_mode *mode; + + memset(blk_key, 0, sizeof(*blk_key)); + + if (crypto_mode >= ARRAY_SIZE(blk_crypto_modes)) + return -EINVAL; + + mode = &blk_crypto_modes[crypto_mode]; + if (mode->keysize == 0) + return -EINVAL; + + if (dun_bytes == 0 || dun_bytes > BLK_CRYPTO_MAX_IV_SIZE) + return -EINVAL; + + if (!is_power_of_2(data_unit_size)) + return -EINVAL; + + blk_key->crypto_cfg.crypto_mode = crypto_mode; + blk_key->crypto_cfg.dun_bytes = dun_bytes; + blk_key->crypto_cfg.data_unit_size = data_unit_size; + blk_key->data_unit_size_bits = ilog2(data_unit_size); + blk_key->size = mode->keysize; + memcpy(blk_key->raw, raw_key, mode->keysize); + + return 0; +} + +bool blk_crypto_config_supported(struct request_queue *q, + const struct blk_crypto_config *cfg) +{ + return blk_ksm_crypto_cfg_supported(q->ksm, cfg); +} + +/** + * blk_crypto_start_using_key() - Start using a blk_crypto_key on a device + * @key: A key to use on the device + * @q: the request queue for the device + * + * Upper layers must call this function to ensure that the hardware supports + * the key's crypto settings. + * + * Return: 0 on success; -ENOPKG if the hardware doesn't support the key + */ +int blk_crypto_start_using_key(const struct blk_crypto_key *key, + struct request_queue *q) +{ + if (blk_ksm_crypto_cfg_supported(q->ksm, &key->crypto_cfg)) + return 0; + return -ENOPKG; +} + +/** + * blk_crypto_evict_key() - Evict a key from any inline encryption hardware + * it may have been programmed into + * @q: The request queue who's associated inline encryption hardware this key + * might have been programmed into + * @key: The key to evict + * + * Upper layers (filesystems) must call this function to ensure that a key is + * evicted from any hardware that it might have been programmed into. The key + * must not be in use by any in-flight IO when this function is called. + * + * Return: 0 on success or if key is not present in the q's ksm, -err on error. + */ +int blk_crypto_evict_key(struct request_queue *q, + const struct blk_crypto_key *key) +{ + if (blk_ksm_crypto_cfg_supported(q->ksm, &key->crypto_cfg)) + return blk_ksm_evict_key(q->ksm, key); + + return 0; +} diff --git a/block/blk-map.c b/block/blk-map.c index e3e4ac48db45..6e804892d5ec 100644 --- a/block/blk-map.c +++ b/block/blk-map.c @@ -550,6 +550,7 @@ int blk_rq_append_bio(struct request *rq, struct bio **bio) rq->biotail->bi_next = *bio; rq->biotail = *bio; rq->__data_len += (*bio)->bi_iter.bi_size; + bio_crypt_free_ctx(*bio); } return 0; diff --git a/block/blk-merge.c b/block/blk-merge.c index a04e991b5ded..1a9036398214 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -562,6 +562,8 @@ int ll_back_merge_fn(struct request *req, struct bio *bio, unsigned int nr_segs) if (blk_integrity_rq(req) && integrity_req_gap_back_merge(req, bio)) return 0; + if (!bio_crypt_ctx_back_mergeable(req, bio)) + return 0; if (blk_rq_sectors(req) + bio_sectors(bio) > blk_rq_get_max_sectors(req, blk_rq_pos(req))) { req_set_nomerge(req->q, req); @@ -578,6 +580,8 @@ int ll_front_merge_fn(struct request *req, struct bio *bio, unsigned int nr_segs if (blk_integrity_rq(req) && integrity_req_gap_front_merge(req, bio)) return 0; + if (!bio_crypt_ctx_front_mergeable(req, bio)) + return 0; if (blk_rq_sectors(req) + bio_sectors(bio) > blk_rq_get_max_sectors(req, bio->bi_iter.bi_sector)) { req_set_nomerge(req->q, req); @@ -627,6 +631,9 @@ static int ll_merge_requests_fn(struct request_queue *q, struct request *req, if (blk_integrity_merge_rq(q, req, next) == false) return 0; + if (!bio_crypt_ctx_merge_rq(req, next)) + return 0; + /* Merge is OK... */ req->nr_phys_segments = total_phys_segments; return 1; @@ -851,6 +858,10 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio) if (blk_integrity_merge_bio(rq->q, rq, bio) == false) return false; + /* Only merge if the crypt contexts are compatible */ + if (!bio_crypt_rq_ctx_compatible(rq, bio)) + return false; + /* must be using the same buffer */ if (req_op(rq) == REQ_OP_WRITE_SAME && !blk_write_same_mergeable(rq->bio, bio)) diff --git a/block/blk-mq.c b/block/blk-mq.c index 9ee695bdf873..4f8adef7fd0d 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -26,6 +26,7 @@ #include #include #include +#include #include @@ -317,6 +318,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, #if defined(CONFIG_BLK_DEV_INTEGRITY) rq->nr_integrity_segments = 0; #endif + blk_crypto_rq_set_defaults(rq); /* tag was already set */ WRITE_ONCE(rq->deadline, 0); @@ -473,6 +475,7 @@ static void __blk_mq_free_request(struct request *rq) struct blk_mq_hw_ctx *hctx = rq->mq_hctx; const int sched_tag = rq->internal_tag; + blk_crypto_free_request(rq); blk_pm_mark_last_busy(rq); rq->mq_hctx = NULL; if (rq->tag != -1) @@ -1820,6 +1823,7 @@ static void blk_mq_bio_to_request(struct request *rq, struct bio *bio, rq->__sector = bio->bi_iter.bi_sector; rq->write_hint = bio->bi_write_hint; blk_rq_bio_prep(rq, bio, nr_segs); + blk_crypto_rq_bio_prep(rq, bio, GFP_NOIO); blk_account_io_start(rq, true); } @@ -2021,6 +2025,7 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) struct request *same_queue_rq = NULL; unsigned int nr_segs; blk_qc_t cookie; + blk_status_t ret; blk_queue_bounce(q, &bio); __blk_queue_split(q, &bio, &nr_segs); @@ -2054,6 +2059,14 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) blk_mq_bio_to_request(rq, bio, nr_segs); + ret = blk_crypto_init_request(rq); + if (ret != BLK_STS_OK) { + bio->bi_status = ret; + bio_endio(bio); + blk_mq_free_request(rq); + return BLK_QC_T_NONE; + } + plug = blk_mq_plug(q, bio); if (unlikely(is_flush_fua)) { /* Bypass scheduler for flush requests */ diff --git a/block/blk.h b/block/blk.h index e5cd350ca379..fc00537026a0 100644 --- a/block/blk.h +++ b/block/blk.h @@ -5,7 +5,9 @@ #include #include #include +#include #include +#include "blk-crypto-internal.h" #include "blk-mq.h" #include "blk-mq-sched.h" diff --git a/block/bounce.c b/block/bounce.c index f8ed677a1bf7..c3aaed070124 100644 --- a/block/bounce.c +++ b/block/bounce.c @@ -267,6 +267,8 @@ static struct bio *bounce_clone_bio(struct bio *bio_src, gfp_t gfp_mask, break; } + bio_crypt_clone(bio, bio_src, gfp_mask); + if (bio_integrity(bio_src)) { int ret; diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 0eb93da44ea2..8921cd79422c 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -26,6 +26,7 @@ #include #include #include +#include #define DM_MSG_PREFIX "core" @@ -1334,6 +1335,8 @@ static int clone_bio(struct dm_target_io *tio, struct bio *bio, __bio_clone_fast(clone, bio); + bio_crypt_clone(clone, bio, GFP_NOIO); + if (bio_integrity(bio)) { int r; diff --git a/include/linux/blk-crypto.h b/include/linux/blk-crypto.h index 4e77938c3d0e..76095b07dd90 100644 --- a/include/linux/blk-crypto.h +++ b/include/linux/blk-crypto.h @@ -6,6 +6,8 @@ #ifndef __LINUX_BLK_CRYPTO_H #define __LINUX_BLK_CRYPTO_H +#include + enum blk_crypto_mode_num { BLK_ENCRYPTION_MODE_INVALID, BLK_ENCRYPTION_MODE_AES_256_XTS, @@ -49,4 +51,73 @@ struct blk_crypto_key { u8 raw[BLK_CRYPTO_MAX_KEY_SIZE]; }; +#define BLK_CRYPTO_MAX_IV_SIZE 32 +#define BLK_CRYPTO_DUN_ARRAY_SIZE (BLK_CRYPTO_MAX_IV_SIZE / sizeof(u64)) + +/** + * struct bio_crypt_ctx - an inline encryption context + * @bc_key: the key, algorithm, and data unit size to use + * @bc_dun: the data unit number (starting IV) to use + * + * A bio_crypt_ctx specifies that the contents of the bio will be encrypted (for + * write requests) or decrypted (for read requests) inline by the storage device + * or controller. + */ +struct bio_crypt_ctx { + const struct blk_crypto_key *bc_key; + u64 bc_dun[BLK_CRYPTO_DUN_ARRAY_SIZE]; +}; + +#include +#include + +struct request; +struct request_queue; + +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + +static inline bool bio_has_crypt_ctx(struct bio *bio) +{ + return bio->bi_crypt_context; +} + +void bio_crypt_set_ctx(struct bio *bio, const struct blk_crypto_key *key, + const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], + gfp_t gfp_mask); + +bool bio_crypt_dun_is_contiguous(const struct bio_crypt_ctx *bc, + unsigned int bytes, + const u64 next_dun[BLK_CRYPTO_DUN_ARRAY_SIZE]); + +int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key, + enum blk_crypto_mode_num crypto_mode, + unsigned int dun_bytes, + unsigned int data_unit_size); + +int blk_crypto_start_using_key(const struct blk_crypto_key *key, + struct request_queue *q); + +int blk_crypto_evict_key(struct request_queue *q, + const struct blk_crypto_key *key); + +bool blk_crypto_config_supported(struct request_queue *q, + const struct blk_crypto_config *cfg); + +#else /* CONFIG_BLK_INLINE_ENCRYPTION */ + +static inline bool bio_has_crypt_ctx(struct bio *bio) +{ + return false; +} + +#endif /* CONFIG_BLK_INLINE_ENCRYPTION */ + +void __bio_crypt_clone(struct bio *dst, struct bio *src, gfp_t gfp_mask); +static inline void bio_crypt_clone(struct bio *dst, struct bio *src, + gfp_t gfp_mask) +{ + if (bio_has_crypt_ctx(src)) + __bio_crypt_clone(dst, src, gfp_mask); +} + #endif /* __LINUX_BLK_CRYPTO_H */ diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index b90dca1fa430..9322261fb316 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -18,6 +18,7 @@ struct block_device; struct io_context; struct cgroup_subsys_state; typedef void (bio_end_io_t) (struct bio *); +struct bio_crypt_ctx; /* * Block error status values. See block/blk-core:blk_errors for the details. @@ -185,6 +186,11 @@ struct bio { u64 bi_iocost_cost; #endif #endif + +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + struct bio_crypt_ctx *bi_crypt_context; +#endif + union { #if defined(CONFIG_BLK_DEV_INTEGRITY) struct bio_integrity_payload *bi_integrity; /* data integrity */ diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 354e44eebef9..52a9f456cadf 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -222,6 +222,11 @@ struct request { unsigned short nr_integrity_segments; #endif +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + struct bio_crypt_ctx *crypt_ctx; + struct blk_ksm_keyslot *crypt_keyslot; +#endif + unsigned short write_hint; unsigned short ioprio; -- cgit v1.2.3 From d145dc23030bbf2de3a8ca5e0c29c2e568f69737 Mon Sep 17 00:00:00 2001 From: Satya Tangirala Date: Thu, 14 May 2020 00:37:19 +0000 Subject: block: Make blk-integrity preclude hardware inline encryption Whenever a device supports blk-integrity, make the kernel pretend that the device doesn't support inline encryption (essentially by setting the keyslot manager in the request queue to NULL). There's no hardware currently that supports both integrity and inline encryption. However, it seems possible that there will be such hardware in the near future (like the NVMe key per I/O support that might support both inline encryption and PI). But properly integrating both features is not trivial, and without real hardware that implements both, it is difficult to tell if it will be done correctly by the majority of hardware that support both. So it seems best not to support both features together right now, and to decide what to do at probe time. Signed-off-by: Satya Tangirala Reviewed-by: Eric Biggers Reviewed-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/bio-integrity.c | 3 +++ block/blk-integrity.c | 7 +++++++ block/keyslot-manager.c | 19 +++++++++++++++++++ include/linux/blkdev.h | 30 ++++++++++++++++++++++++++++++ 4 files changed, 59 insertions(+) (limited to 'block') diff --git a/block/bio-integrity.c b/block/bio-integrity.c index bf62c25cde8f..3579ac0f6ec1 100644 --- a/block/bio-integrity.c +++ b/block/bio-integrity.c @@ -42,6 +42,9 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, struct bio_set *bs = bio->bi_pool; unsigned inline_vecs; + if (WARN_ON_ONCE(bio_has_crypt_ctx(bio))) + return ERR_PTR(-EOPNOTSUPP); + if (!bs || !mempool_initialized(&bs->bio_integrity_pool)) { bip = kmalloc(struct_size(bip, bip_inline_vecs, nr_vecs), gfp_mask); inline_vecs = nr_vecs; diff --git a/block/blk-integrity.c b/block/blk-integrity.c index ff1070edbb40..c03705cbb9c9 100644 --- a/block/blk-integrity.c +++ b/block/blk-integrity.c @@ -409,6 +409,13 @@ void blk_integrity_register(struct gendisk *disk, struct blk_integrity *template bi->tag_size = template->tag_size; disk->queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES; + +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + if (disk->queue->ksm) { + pr_warn("blk-integrity: Integrity and hardware inline encryption are not supported together. Disabling hardware inline encryption.\n"); + blk_ksm_unregister(disk->queue); + } +#endif } EXPORT_SYMBOL(blk_integrity_register); diff --git a/block/keyslot-manager.c b/block/keyslot-manager.c index fcd3fd469d7c..c2ef41b3147b 100644 --- a/block/keyslot-manager.c +++ b/block/keyslot-manager.c @@ -25,6 +25,9 @@ * Upper layers will call blk_ksm_get_slot_for_key() to program a * key into some slot in the inline encryption hardware. */ + +#define pr_fmt(fmt) "blk-crypto: " fmt + #include #include #include @@ -376,3 +379,19 @@ void blk_ksm_destroy(struct blk_keyslot_manager *ksm) memzero_explicit(ksm, sizeof(*ksm)); } EXPORT_SYMBOL_GPL(blk_ksm_destroy); + +bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q) +{ + if (blk_integrity_queue_supports_integrity(q)) { + pr_warn("Integrity and hardware inline encryption are not supported together. Disabling hardware inline encryption.\n"); + return false; + } + q->ksm = ksm; + return true; +} +EXPORT_SYMBOL_GPL(blk_ksm_register); + +void blk_ksm_unregister(struct request_queue *q) +{ + q->ksm = NULL; +} diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 52a9f456cadf..2b33166b9daf 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1583,6 +1583,12 @@ struct blk_integrity *bdev_get_integrity(struct block_device *bdev) return blk_get_integrity(bdev->bd_disk); } +static inline bool +blk_integrity_queue_supports_integrity(struct request_queue *q) +{ + return q->integrity.profile; +} + static inline bool blk_integrity_rq(struct request *rq) { return rq->cmd_flags & REQ_INTEGRITY; @@ -1663,6 +1669,11 @@ static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk) { return NULL; } +static inline bool +blk_integrity_queue_supports_integrity(struct request_queue *q) +{ + return false; +} static inline int blk_integrity_compare(struct gendisk *a, struct gendisk *b) { return 0; @@ -1714,6 +1725,25 @@ static inline struct bio_vec *rq_integrity_vec(struct request *rq) #endif /* CONFIG_BLK_DEV_INTEGRITY */ +#ifdef CONFIG_BLK_INLINE_ENCRYPTION + +bool blk_ksm_register(struct blk_keyslot_manager *ksm, struct request_queue *q); + +void blk_ksm_unregister(struct request_queue *q); + +#else /* CONFIG_BLK_INLINE_ENCRYPTION */ + +static inline bool blk_ksm_register(struct blk_keyslot_manager *ksm, + struct request_queue *q) +{ + return true; +} + +static inline void blk_ksm_unregister(struct request_queue *q) { } + +#endif /* CONFIG_BLK_INLINE_ENCRYPTION */ + + struct block_device_operations { int (*open) (struct block_device *, fmode_t); void (*release) (struct gendisk *, fmode_t); -- cgit v1.2.3 From 488f6682c832e9549d28b30075f00c76328eb1be Mon Sep 17 00:00:00 2001 From: Satya Tangirala Date: Thu, 14 May 2020 00:37:20 +0000 Subject: block: blk-crypto-fallback for Inline Encryption Blk-crypto delegates crypto operations to inline encryption hardware when available. The separately configurable blk-crypto-fallback contains a software fallback to the kernel crypto API - when enabled, blk-crypto will use this fallback for en/decryption when inline encryption hardware is not available. This lets upper layers not have to worry about whether or not the underlying device has support for inline encryption before deciding to specify an encryption context for a bio. It also allows for testing without actual inline encryption hardware - in particular, it makes it possible to test the inline encryption code in ext4 and f2fs simply by running xfstests with the inlinecrypt mount option, which in turn allows for things like the regular upstream regression testing of ext4 to cover the inline encryption code paths. For more details, refer to Documentation/block/inline-encryption.rst. Signed-off-by: Satya Tangirala Reviewed-by: Eric Biggers Signed-off-by: Jens Axboe --- block/Kconfig | 10 + block/Makefile | 1 + block/blk-crypto-fallback.c | 657 ++++++++++++++++++++++++++++++++++++++++++++ block/blk-crypto-internal.h | 35 +++ block/blk-crypto.c | 68 +++-- include/linux/blk-crypto.h | 2 +- 6 files changed, 752 insertions(+), 21 deletions(-) create mode 100644 block/blk-crypto-fallback.c (limited to 'block') diff --git a/block/Kconfig b/block/Kconfig index f8870c316a03..9382a4acefc3 100644 --- a/block/Kconfig +++ b/block/Kconfig @@ -193,6 +193,16 @@ config BLK_INLINE_ENCRYPTION block layer handle encryption, so users can take advantage of inline encryption hardware if present. +config BLK_INLINE_ENCRYPTION_FALLBACK + bool "Enable crypto API fallback for blk-crypto" + depends on BLK_INLINE_ENCRYPTION + select CRYPTO + select CRYPTO_SKCIPHER + help + Enabling this lets the block layer handle inline encryption + by falling back to the kernel crypto API when inline + encryption hardware is not present. + menu "Partition Types" source "block/partitions/Kconfig" diff --git a/block/Makefile b/block/Makefile index 3ee88d3e807d..78719169fb2a 100644 --- a/block/Makefile +++ b/block/Makefile @@ -37,3 +37,4 @@ obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o obj-$(CONFIG_BLK_SED_OPAL) += sed-opal.o obj-$(CONFIG_BLK_PM) += blk-pm.o obj-$(CONFIG_BLK_INLINE_ENCRYPTION) += keyslot-manager.o blk-crypto.o +obj-$(CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK) += blk-crypto-fallback.o diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c new file mode 100644 index 000000000000..74ab137ae3ba --- /dev/null +++ b/block/blk-crypto-fallback.c @@ -0,0 +1,657 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright 2019 Google LLC + */ + +/* + * Refer to Documentation/block/inline-encryption.rst for detailed explanation. + */ + +#define pr_fmt(fmt) "blk-crypto-fallback: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "blk-crypto-internal.h" + +static unsigned int num_prealloc_bounce_pg = 32; +module_param(num_prealloc_bounce_pg, uint, 0); +MODULE_PARM_DESC(num_prealloc_bounce_pg, + "Number of preallocated bounce pages for the blk-crypto crypto API fallback"); + +static unsigned int blk_crypto_num_keyslots = 100; +module_param_named(num_keyslots, blk_crypto_num_keyslots, uint, 0); +MODULE_PARM_DESC(num_keyslots, + "Number of keyslots for the blk-crypto crypto API fallback"); + +static unsigned int num_prealloc_fallback_crypt_ctxs = 128; +module_param(num_prealloc_fallback_crypt_ctxs, uint, 0); +MODULE_PARM_DESC(num_prealloc_crypt_fallback_ctxs, + "Number of preallocated bio fallback crypto contexts for blk-crypto to use during crypto API fallback"); + +struct bio_fallback_crypt_ctx { + struct bio_crypt_ctx crypt_ctx; + /* + * Copy of the bvec_iter when this bio was submitted. + * We only want to en/decrypt the part of the bio as described by the + * bvec_iter upon submission because bio might be split before being + * resubmitted + */ + struct bvec_iter crypt_iter; + union { + struct { + struct work_struct work; + struct bio *bio; + }; + struct { + void *bi_private_orig; + bio_end_io_t *bi_end_io_orig; + }; + }; +}; + +static struct kmem_cache *bio_fallback_crypt_ctx_cache; +static mempool_t *bio_fallback_crypt_ctx_pool; + +/* + * Allocating a crypto tfm during I/O can deadlock, so we have to preallocate + * all of a mode's tfms when that mode starts being used. Since each mode may + * need all the keyslots at some point, each mode needs its own tfm for each + * keyslot; thus, a keyslot may contain tfms for multiple modes. However, to + * match the behavior of real inline encryption hardware (which only supports a + * single encryption context per keyslot), we only allow one tfm per keyslot to + * be used at a time - the rest of the unused tfms have their keys cleared. + */ +static DEFINE_MUTEX(tfms_init_lock); +static bool tfms_inited[BLK_ENCRYPTION_MODE_MAX]; + +static struct blk_crypto_keyslot { + enum blk_crypto_mode_num crypto_mode; + struct crypto_skcipher *tfms[BLK_ENCRYPTION_MODE_MAX]; +} *blk_crypto_keyslots; + +static struct blk_keyslot_manager blk_crypto_ksm; +static struct workqueue_struct *blk_crypto_wq; +static mempool_t *blk_crypto_bounce_page_pool; + +/* + * This is the key we set when evicting a keyslot. This *should* be the all 0's + * key, but AES-XTS rejects that key, so we use some random bytes instead. + */ +static u8 blank_key[BLK_CRYPTO_MAX_KEY_SIZE]; + +static void blk_crypto_evict_keyslot(unsigned int slot) +{ + struct blk_crypto_keyslot *slotp = &blk_crypto_keyslots[slot]; + enum blk_crypto_mode_num crypto_mode = slotp->crypto_mode; + int err; + + WARN_ON(slotp->crypto_mode == BLK_ENCRYPTION_MODE_INVALID); + + /* Clear the key in the skcipher */ + err = crypto_skcipher_setkey(slotp->tfms[crypto_mode], blank_key, + blk_crypto_modes[crypto_mode].keysize); + WARN_ON(err); + slotp->crypto_mode = BLK_ENCRYPTION_MODE_INVALID; +} + +static int blk_crypto_keyslot_program(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key, + unsigned int slot) +{ + struct blk_crypto_keyslot *slotp = &blk_crypto_keyslots[slot]; + const enum blk_crypto_mode_num crypto_mode = + key->crypto_cfg.crypto_mode; + int err; + + if (crypto_mode != slotp->crypto_mode && + slotp->crypto_mode != BLK_ENCRYPTION_MODE_INVALID) + blk_crypto_evict_keyslot(slot); + + slotp->crypto_mode = crypto_mode; + err = crypto_skcipher_setkey(slotp->tfms[crypto_mode], key->raw, + key->size); + if (err) { + blk_crypto_evict_keyslot(slot); + return err; + } + return 0; +} + +static int blk_crypto_keyslot_evict(struct blk_keyslot_manager *ksm, + const struct blk_crypto_key *key, + unsigned int slot) +{ + blk_crypto_evict_keyslot(slot); + return 0; +} + +/* + * The crypto API fallback KSM ops - only used for a bio when it specifies a + * blk_crypto_key that was not supported by the device's inline encryption + * hardware. + */ +static const struct blk_ksm_ll_ops blk_crypto_ksm_ll_ops = { + .keyslot_program = blk_crypto_keyslot_program, + .keyslot_evict = blk_crypto_keyslot_evict, +}; + +static void blk_crypto_fallback_encrypt_endio(struct bio *enc_bio) +{ + struct bio *src_bio = enc_bio->bi_private; + int i; + + for (i = 0; i < enc_bio->bi_vcnt; i++) + mempool_free(enc_bio->bi_io_vec[i].bv_page, + blk_crypto_bounce_page_pool); + + src_bio->bi_status = enc_bio->bi_status; + + bio_put(enc_bio); + bio_endio(src_bio); +} + +static struct bio *blk_crypto_clone_bio(struct bio *bio_src) +{ + struct bvec_iter iter; + struct bio_vec bv; + struct bio *bio; + + bio = bio_alloc_bioset(GFP_NOIO, bio_segments(bio_src), NULL); + if (!bio) + return NULL; + bio->bi_disk = bio_src->bi_disk; + bio->bi_opf = bio_src->bi_opf; + bio->bi_ioprio = bio_src->bi_ioprio; + bio->bi_write_hint = bio_src->bi_write_hint; + bio->bi_iter.bi_sector = bio_src->bi_iter.bi_sector; + bio->bi_iter.bi_size = bio_src->bi_iter.bi_size; + + bio_for_each_segment(bv, bio_src, iter) + bio->bi_io_vec[bio->bi_vcnt++] = bv; + + bio_clone_blkg_association(bio, bio_src); + blkcg_bio_issue_init(bio); + + return bio; +} + +static bool blk_crypto_alloc_cipher_req(struct blk_ksm_keyslot *slot, + struct skcipher_request **ciph_req_ret, + struct crypto_wait *wait) +{ + struct skcipher_request *ciph_req; + const struct blk_crypto_keyslot *slotp; + int keyslot_idx = blk_ksm_get_slot_idx(slot); + + slotp = &blk_crypto_keyslots[keyslot_idx]; + ciph_req = skcipher_request_alloc(slotp->tfms[slotp->crypto_mode], + GFP_NOIO); + if (!ciph_req) + return false; + + skcipher_request_set_callback(ciph_req, + CRYPTO_TFM_REQ_MAY_BACKLOG | + CRYPTO_TFM_REQ_MAY_SLEEP, + crypto_req_done, wait); + *ciph_req_ret = ciph_req; + + return true; +} + +static bool blk_crypto_split_bio_if_needed(struct bio **bio_ptr) +{ + struct bio *bio = *bio_ptr; + unsigned int i = 0; + unsigned int num_sectors = 0; + struct bio_vec bv; + struct bvec_iter iter; + + bio_for_each_segment(bv, bio, iter) { + num_sectors += bv.bv_len >> SECTOR_SHIFT; + if (++i == BIO_MAX_PAGES) + break; + } + if (num_sectors < bio_sectors(bio)) { + struct bio *split_bio; + + split_bio = bio_split(bio, num_sectors, GFP_NOIO, NULL); + if (!split_bio) { + bio->bi_status = BLK_STS_RESOURCE; + return false; + } + bio_chain(split_bio, bio); + generic_make_request(bio); + *bio_ptr = split_bio; + } + + return true; +} + +union blk_crypto_iv { + __le64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE]; + u8 bytes[BLK_CRYPTO_MAX_IV_SIZE]; +}; + +static void blk_crypto_dun_to_iv(const u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], + union blk_crypto_iv *iv) +{ + int i; + + for (i = 0; i < BLK_CRYPTO_DUN_ARRAY_SIZE; i++) + iv->dun[i] = cpu_to_le64(dun[i]); +} + +/* + * The crypto API fallback's encryption routine. + * Allocate a bounce bio for encryption, encrypt the input bio using crypto API, + * and replace *bio_ptr with the bounce bio. May split input bio if it's too + * large. Returns true on success. Returns false and sets bio->bi_status on + * error. + */ +static bool blk_crypto_fallback_encrypt_bio(struct bio **bio_ptr) +{ + struct bio *src_bio, *enc_bio; + struct bio_crypt_ctx *bc; + struct blk_ksm_keyslot *slot; + int data_unit_size; + struct skcipher_request *ciph_req = NULL; + DECLARE_CRYPTO_WAIT(wait); + u64 curr_dun[BLK_CRYPTO_DUN_ARRAY_SIZE]; + struct scatterlist src, dst; + union blk_crypto_iv iv; + unsigned int i, j; + bool ret = false; + blk_status_t blk_st; + + /* Split the bio if it's too big for single page bvec */ + if (!blk_crypto_split_bio_if_needed(bio_ptr)) + return false; + + src_bio = *bio_ptr; + bc = src_bio->bi_crypt_context; + data_unit_size = bc->bc_key->crypto_cfg.data_unit_size; + + /* Allocate bounce bio for encryption */ + enc_bio = blk_crypto_clone_bio(src_bio); + if (!enc_bio) { + src_bio->bi_status = BLK_STS_RESOURCE; + return false; + } + + /* + * Use the crypto API fallback keyslot manager to get a crypto_skcipher + * for the algorithm and key specified for this bio. + */ + blk_st = blk_ksm_get_slot_for_key(&blk_crypto_ksm, bc->bc_key, &slot); + if (blk_st != BLK_STS_OK) { + src_bio->bi_status = blk_st; + goto out_put_enc_bio; + } + + /* and then allocate an skcipher_request for it */ + if (!blk_crypto_alloc_cipher_req(slot, &ciph_req, &wait)) { + src_bio->bi_status = BLK_STS_RESOURCE; + goto out_release_keyslot; + } + + memcpy(curr_dun, bc->bc_dun, sizeof(curr_dun)); + sg_init_table(&src, 1); + sg_init_table(&dst, 1); + + skcipher_request_set_crypt(ciph_req, &src, &dst, data_unit_size, + iv.bytes); + + /* Encrypt each page in the bounce bio */ + for (i = 0; i < enc_bio->bi_vcnt; i++) { + struct bio_vec *enc_bvec = &enc_bio->bi_io_vec[i]; + struct page *plaintext_page = enc_bvec->bv_page; + struct page *ciphertext_page = + mempool_alloc(blk_crypto_bounce_page_pool, GFP_NOIO); + + enc_bvec->bv_page = ciphertext_page; + + if (!ciphertext_page) { + src_bio->bi_status = BLK_STS_RESOURCE; + goto out_free_bounce_pages; + } + + sg_set_page(&src, plaintext_page, data_unit_size, + enc_bvec->bv_offset); + sg_set_page(&dst, ciphertext_page, data_unit_size, + enc_bvec->bv_offset); + + /* Encrypt each data unit in this page */ + for (j = 0; j < enc_bvec->bv_len; j += data_unit_size) { + blk_crypto_dun_to_iv(curr_dun, &iv); + if (crypto_wait_req(crypto_skcipher_encrypt(ciph_req), + &wait)) { + i++; + src_bio->bi_status = BLK_STS_IOERR; + goto out_free_bounce_pages; + } + bio_crypt_dun_increment(curr_dun, 1); + src.offset += data_unit_size; + dst.offset += data_unit_size; + } + } + + enc_bio->bi_private = src_bio; + enc_bio->bi_end_io = blk_crypto_fallback_encrypt_endio; + *bio_ptr = enc_bio; + ret = true; + + enc_bio = NULL; + goto out_free_ciph_req; + +out_free_bounce_pages: + while (i > 0) + mempool_free(enc_bio->bi_io_vec[--i].bv_page, + blk_crypto_bounce_page_pool); +out_free_ciph_req: + skcipher_request_free(ciph_req); +out_release_keyslot: + blk_ksm_put_slot(slot); +out_put_enc_bio: + if (enc_bio) + bio_put(enc_bio); + + return ret; +} + +/* + * The crypto API fallback's main decryption routine. + * Decrypts input bio in place, and calls bio_endio on the bio. + */ +static void blk_crypto_fallback_decrypt_bio(struct work_struct *work) +{ + struct bio_fallback_crypt_ctx *f_ctx = + container_of(work, struct bio_fallback_crypt_ctx, work); + struct bio *bio = f_ctx->bio; + struct bio_crypt_ctx *bc = &f_ctx->crypt_ctx; + struct blk_ksm_keyslot *slot; + struct skcipher_request *ciph_req = NULL; + DECLARE_CRYPTO_WAIT(wait); + u64 curr_dun[BLK_CRYPTO_DUN_ARRAY_SIZE]; + union blk_crypto_iv iv; + struct scatterlist sg; + struct bio_vec bv; + struct bvec_iter iter; + const int data_unit_size = bc->bc_key->crypto_cfg.data_unit_size; + unsigned int i; + blk_status_t blk_st; + + /* + * Use the crypto API fallback keyslot manager to get a crypto_skcipher + * for the algorithm and key specified for this bio. + */ + blk_st = blk_ksm_get_slot_for_key(&blk_crypto_ksm, bc->bc_key, &slot); + if (blk_st != BLK_STS_OK) { + bio->bi_status = blk_st; + goto out_no_keyslot; + } + + /* and then allocate an skcipher_request for it */ + if (!blk_crypto_alloc_cipher_req(slot, &ciph_req, &wait)) { + bio->bi_status = BLK_STS_RESOURCE; + goto out; + } + + memcpy(curr_dun, bc->bc_dun, sizeof(curr_dun)); + sg_init_table(&sg, 1); + skcipher_request_set_crypt(ciph_req, &sg, &sg, data_unit_size, + iv.bytes); + + /* Decrypt each segment in the bio */ + __bio_for_each_segment(bv, bio, iter, f_ctx->crypt_iter) { + struct page *page = bv.bv_page; + + sg_set_page(&sg, page, data_unit_size, bv.bv_offset); + + /* Decrypt each data unit in the segment */ + for (i = 0; i < bv.bv_len; i += data_unit_size) { + blk_crypto_dun_to_iv(curr_dun, &iv); + if (crypto_wait_req(crypto_skcipher_decrypt(ciph_req), + &wait)) { + bio->bi_status = BLK_STS_IOERR; + goto out; + } + bio_crypt_dun_increment(curr_dun, 1); + sg.offset += data_unit_size; + } + } + +out: + skcipher_request_free(ciph_req); + blk_ksm_put_slot(slot); +out_no_keyslot: + mempool_free(f_ctx, bio_fallback_crypt_ctx_pool); + bio_endio(bio); +} + +/** + * blk_crypto_fallback_decrypt_endio - queue bio for fallback decryption + * + * @bio: the bio to queue + * + * Restore bi_private and bi_end_io, and queue the bio for decryption into a + * workqueue, since this function will be called from an atomic context. + */ +static void blk_crypto_fallback_decrypt_endio(struct bio *bio) +{ + struct bio_fallback_crypt_ctx *f_ctx = bio->bi_private; + + bio->bi_private = f_ctx->bi_private_orig; + bio->bi_end_io = f_ctx->bi_end_io_orig; + + /* If there was an IO error, don't queue for decrypt. */ + if (bio->bi_status) { + mempool_free(f_ctx, bio_fallback_crypt_ctx_pool); + bio_endio(bio); + return; + } + + INIT_WORK(&f_ctx->work, blk_crypto_fallback_decrypt_bio); + f_ctx->bio = bio; + queue_work(blk_crypto_wq, &f_ctx->work); +} + +/** + * blk_crypto_fallback_bio_prep - Prepare a bio to use fallback en/decryption + * + * @bio_ptr: pointer to the bio to prepare + * + * If bio is doing a WRITE operation, this splits the bio into two parts if it's + * too big (see blk_crypto_split_bio_if_needed). It then allocates a bounce bio + * for the first part, encrypts it, and update bio_ptr to point to the bounce + * bio. + * + * For a READ operation, we mark the bio for decryption by using bi_private and + * bi_end_io. + * + * In either case, this function will make the bio look like a regular bio (i.e. + * as if no encryption context was ever specified) for the purposes of the rest + * of the stack except for blk-integrity (blk-integrity and blk-crypto are not + * currently supported together). + * + * Return: true on success. Sets bio->bi_status and returns false on error. + */ +bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr) +{ + struct bio *bio = *bio_ptr; + struct bio_crypt_ctx *bc = bio->bi_crypt_context; + struct bio_fallback_crypt_ctx *f_ctx; + + if (WARN_ON_ONCE(!tfms_inited[bc->bc_key->crypto_cfg.crypto_mode])) { + /* User didn't call blk_crypto_start_using_key() first */ + bio->bi_status = BLK_STS_IOERR; + return false; + } + + if (!blk_ksm_crypto_cfg_supported(&blk_crypto_ksm, + &bc->bc_key->crypto_cfg)) { + bio->bi_status = BLK_STS_NOTSUPP; + return false; + } + + if (bio_data_dir(bio) == WRITE) + return blk_crypto_fallback_encrypt_bio(bio_ptr); + + /* + * bio READ case: Set up a f_ctx in the bio's bi_private and set the + * bi_end_io appropriately to trigger decryption when the bio is ended. + */ + f_ctx = mempool_alloc(bio_fallback_crypt_ctx_pool, GFP_NOIO); + f_ctx->crypt_ctx = *bc; + f_ctx->crypt_iter = bio->bi_iter; + f_ctx->bi_private_orig = bio->bi_private; + f_ctx->bi_end_io_orig = bio->bi_end_io; + bio->bi_private = (void *)f_ctx; + bio->bi_end_io = blk_crypto_fallback_decrypt_endio; + bio_crypt_free_ctx(bio); + + return true; +} + +int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key) +{ + return blk_ksm_evict_key(&blk_crypto_ksm, key); +} + +static bool blk_crypto_fallback_inited; +static int blk_crypto_fallback_init(void) +{ + int i; + int err = -ENOMEM; + + if (blk_crypto_fallback_inited) + return 0; + + prandom_bytes(blank_key, BLK_CRYPTO_MAX_KEY_SIZE); + + err = blk_ksm_init(&blk_crypto_ksm, blk_crypto_num_keyslots); + if (err) + goto out; + err = -ENOMEM; + + blk_crypto_ksm.ksm_ll_ops = blk_crypto_ksm_ll_ops; + blk_crypto_ksm.max_dun_bytes_supported = BLK_CRYPTO_MAX_IV_SIZE; + + /* All blk-crypto modes have a crypto API fallback. */ + for (i = 0; i < BLK_ENCRYPTION_MODE_MAX; i++) + blk_crypto_ksm.crypto_modes_supported[i] = 0xFFFFFFFF; + blk_crypto_ksm.crypto_modes_supported[BLK_ENCRYPTION_MODE_INVALID] = 0; + + blk_crypto_wq = alloc_workqueue("blk_crypto_wq", + WQ_UNBOUND | WQ_HIGHPRI | + WQ_MEM_RECLAIM, num_online_cpus()); + if (!blk_crypto_wq) + goto fail_free_ksm; + + blk_crypto_keyslots = kcalloc(blk_crypto_num_keyslots, + sizeof(blk_crypto_keyslots[0]), + GFP_KERNEL); + if (!blk_crypto_keyslots) + goto fail_free_wq; + + blk_crypto_bounce_page_pool = + mempool_create_page_pool(num_prealloc_bounce_pg, 0); + if (!blk_crypto_bounce_page_pool) + goto fail_free_keyslots; + + bio_fallback_crypt_ctx_cache = KMEM_CACHE(bio_fallback_crypt_ctx, 0); + if (!bio_fallback_crypt_ctx_cache) + goto fail_free_bounce_page_pool; + + bio_fallback_crypt_ctx_pool = + mempool_create_slab_pool(num_prealloc_fallback_crypt_ctxs, + bio_fallback_crypt_ctx_cache); + if (!bio_fallback_crypt_ctx_pool) + goto fail_free_crypt_ctx_cache; + + blk_crypto_fallback_inited = true; + + return 0; +fail_free_crypt_ctx_cache: + kmem_cache_destroy(bio_fallback_crypt_ctx_cache); +fail_free_bounce_page_pool: + mempool_destroy(blk_crypto_bounce_page_pool); +fail_free_keyslots: + kfree(blk_crypto_keyslots); +fail_free_wq: + destroy_workqueue(blk_crypto_wq); +fail_free_ksm: + blk_ksm_destroy(&blk_crypto_ksm); +out: + return err; +} + +/* + * Prepare blk-crypto-fallback for the specified crypto mode. + * Returns -ENOPKG if the needed crypto API support is missing. + */ +int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num) +{ + const char *cipher_str = blk_crypto_modes[mode_num].cipher_str; + struct blk_crypto_keyslot *slotp; + unsigned int i; + int err = 0; + + /* + * Fast path + * Ensure that updates to blk_crypto_keyslots[i].tfms[mode_num] + * for each i are visible before we try to access them. + */ + if (likely(smp_load_acquire(&tfms_inited[mode_num]))) + return 0; + + mutex_lock(&tfms_init_lock); + if (tfms_inited[mode_num]) + goto out; + + err = blk_crypto_fallback_init(); + if (err) + goto out; + + for (i = 0; i < blk_crypto_num_keyslots; i++) { + slotp = &blk_crypto_keyslots[i]; + slotp->tfms[mode_num] = crypto_alloc_skcipher(cipher_str, 0, 0); + if (IS_ERR(slotp->tfms[mode_num])) { + err = PTR_ERR(slotp->tfms[mode_num]); + if (err == -ENOENT) { + pr_warn_once("Missing crypto API support for \"%s\"\n", + cipher_str); + err = -ENOPKG; + } + slotp->tfms[mode_num] = NULL; + goto out_free_tfms; + } + + crypto_skcipher_set_flags(slotp->tfms[mode_num], + CRYPTO_TFM_REQ_FORBID_WEAK_KEYS); + } + + /* + * Ensure that updates to blk_crypto_keyslots[i].tfms[mode_num] + * for each i are visible before we set tfms_inited[mode_num]. + */ + smp_store_release(&tfms_inited[mode_num], true); + goto out; + +out_free_tfms: + for (i = 0; i < blk_crypto_num_keyslots; i++) { + slotp = &blk_crypto_keyslots[i]; + crypto_free_skcipher(slotp->tfms[mode_num]); + slotp->tfms[mode_num] = NULL; + } +out: + mutex_unlock(&tfms_init_lock); + return err; +} diff --git a/block/blk-crypto-internal.h b/block/blk-crypto-internal.h index 796f757fe8e9..d2b0f565d83c 100644 --- a/block/blk-crypto-internal.h +++ b/block/blk-crypto-internal.h @@ -11,10 +11,13 @@ /* Represents a crypto mode supported by blk-crypto */ struct blk_crypto_mode { + const char *cipher_str; /* crypto API name (for fallback case) */ unsigned int keysize; /* key size in bytes */ unsigned int ivsize; /* iv size in bytes */ }; +extern const struct blk_crypto_mode blk_crypto_modes[]; + #ifdef CONFIG_BLK_INLINE_ENCRYPTION void bio_crypt_dun_increment(u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE], @@ -163,4 +166,36 @@ static inline blk_status_t blk_crypto_insert_cloned_request(struct request *rq) return BLK_STS_OK; } +#ifdef CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK + +int blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num); + +bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr); + +int blk_crypto_fallback_evict_key(const struct blk_crypto_key *key); + +#else /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */ + +static inline int +blk_crypto_fallback_start_using_mode(enum blk_crypto_mode_num mode_num) +{ + pr_warn_once("crypto API fallback is disabled\n"); + return -ENOPKG; +} + +static inline bool blk_crypto_fallback_bio_prep(struct bio **bio_ptr) +{ + pr_warn_once("crypto API fallback disabled; failing request.\n"); + (*bio_ptr)->bi_status = BLK_STS_NOTSUPP; + return false; +} + +static inline int +blk_crypto_fallback_evict_key(const struct blk_crypto_key *key) +{ + return 0; +} + +#endif /* CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK */ + #endif /* __LINUX_BLK_CRYPTO_INTERNAL_H */ diff --git a/block/blk-crypto.c b/block/blk-crypto.c index 25b981257f5f..6533c9b36ab8 100644 --- a/block/blk-crypto.c +++ b/block/blk-crypto.c @@ -19,14 +19,17 @@ const struct blk_crypto_mode blk_crypto_modes[] = { [BLK_ENCRYPTION_MODE_AES_256_XTS] = { + .cipher_str = "xts(aes)", .keysize = 64, .ivsize = 16, }, [BLK_ENCRYPTION_MODE_AES_128_CBC_ESSIV] = { + .cipher_str = "essiv(cbc(aes),sha256)", .keysize = 16, .ivsize = 16, }, [BLK_ENCRYPTION_MODE_ADIANTUM] = { + .cipher_str = "adiantum(xchacha12,aes)", .keysize = 32, .ivsize = 32, }, @@ -229,9 +232,16 @@ void __blk_crypto_free_request(struct request *rq) * * @bio_ptr: pointer to original bio pointer * - * Succeeds if the bio doesn't have inline encryption enabled or if the bio - * crypt context provided for the bio is supported by the underlying device's - * inline encryption hardware. Ends the bio with error otherwise. + * If the bio crypt context provided for the bio is supported by the underlying + * device's inline encryption hardware, do nothing. + * + * Otherwise, try to perform en/decryption for this bio by falling back to the + * kernel crypto API. When the crypto API fallback is used for encryption, + * blk-crypto may choose to split the bio into 2 - the first one that will + * continue to be processed and the second one that will be resubmitted via + * generic_make_request. A bounce bio will be allocated to encrypt the contents + * of the aforementioned "first one", and *bio_ptr will be updated to this + * bounce bio. * * Caller must ensure bio has bio_crypt_ctx. * @@ -243,27 +253,29 @@ bool __blk_crypto_bio_prep(struct bio **bio_ptr) { struct bio *bio = *bio_ptr; const struct blk_crypto_key *bc_key = bio->bi_crypt_context->bc_key; - blk_status_t blk_st = BLK_STS_IOERR; /* Error if bio has no data. */ - if (WARN_ON_ONCE(!bio_has_data(bio))) + if (WARN_ON_ONCE(!bio_has_data(bio))) { + bio->bi_status = BLK_STS_IOERR; goto fail; + } - if (!bio_crypt_check_alignment(bio)) + if (!bio_crypt_check_alignment(bio)) { + bio->bi_status = BLK_STS_IOERR; goto fail; + } /* - * Success if device supports the encryption context. + * Success if device supports the encryption context, or if we succeeded + * in falling back to the crypto API. */ - if (!blk_ksm_crypto_cfg_supported(bio->bi_disk->queue->ksm, - &bc_key->crypto_cfg)) { - blk_st = BLK_STS_NOTSUPP; - goto fail; - } + if (blk_ksm_crypto_cfg_supported(bio->bi_disk->queue->ksm, + &bc_key->crypto_cfg)) + return true; - return true; + if (blk_crypto_fallback_bio_prep(bio_ptr)) + return true; fail: - (*bio_ptr)->bi_status = blk_st; bio_endio(*bio_ptr); return false; } @@ -329,10 +341,16 @@ int blk_crypto_init_key(struct blk_crypto_key *blk_key, const u8 *raw_key, return 0; } +/* + * Check if bios with @cfg can be en/decrypted by blk-crypto (i.e. either the + * request queue it's submitted to supports inline crypto, or the + * blk-crypto-fallback is enabled and supports the cfg). + */ bool blk_crypto_config_supported(struct request_queue *q, const struct blk_crypto_config *cfg) { - return blk_ksm_crypto_cfg_supported(q->ksm, cfg); + return IS_ENABLED(CONFIG_BLK_INLINE_ENCRYPTION_FALLBACK) || + blk_ksm_crypto_cfg_supported(q->ksm, cfg); } /** @@ -340,17 +358,22 @@ bool blk_crypto_config_supported(struct request_queue *q, * @key: A key to use on the device * @q: the request queue for the device * - * Upper layers must call this function to ensure that the hardware supports - * the key's crypto settings. + * Upper layers must call this function to ensure that either the hardware + * supports the key's crypto settings, or the crypto API fallback has transforms + * for the needed mode allocated and ready to go. This function may allocate + * an skcipher, and *should not* be called from the data path, since that might + * cause a deadlock * - * Return: 0 on success; -ENOPKG if the hardware doesn't support the key + * Return: 0 on success; -ENOPKG if the hardware doesn't support the key and + * blk-crypto-fallback is either disabled or the needed algorithm + * is disabled in the crypto API; or another -errno code. */ int blk_crypto_start_using_key(const struct blk_crypto_key *key, struct request_queue *q) { if (blk_ksm_crypto_cfg_supported(q->ksm, &key->crypto_cfg)) return 0; - return -ENOPKG; + return blk_crypto_fallback_start_using_mode(key->crypto_cfg.crypto_mode); } /** @@ -372,5 +395,10 @@ int blk_crypto_evict_key(struct request_queue *q, if (blk_ksm_crypto_cfg_supported(q->ksm, &key->crypto_cfg)) return blk_ksm_evict_key(q->ksm, key); - return 0; + /* + * If the request queue's associated inline encryption hardware didn't + * have support for the key, then the key might have been programmed + * into the fallback keyslot manager, so try to evict from there. + */ + return blk_crypto_fallback_evict_key(key); } diff --git a/include/linux/blk-crypto.h b/include/linux/blk-crypto.h index 76095b07dd90..e82342907f2b 100644 --- a/include/linux/blk-crypto.h +++ b/include/linux/blk-crypto.h @@ -61,7 +61,7 @@ struct blk_crypto_key { * * A bio_crypt_ctx specifies that the contents of the bio will be encrypted (for * write requests) or decrypted (for read requests) inline by the storage device - * or controller. + * or controller, or by the crypto API fallback. */ struct bio_crypt_ctx { const struct blk_crypto_key *bc_key; -- cgit v1.2.3 From a5ea5811058ddb91da604afe77acd5ff29babe29 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 16 May 2020 20:27:58 +0200 Subject: blk-mq: move the call to blk_queue_enter_live out of blk_mq_get_request Move the blk_queue_enter_live calls into the callers, where they can successively be cleaned up. Signed-off-by: Christoph Hellwig Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/blk-mq.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 4f8adef7fd0d..b7e06673a30b 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -342,8 +342,6 @@ static struct request *blk_mq_get_request(struct request_queue *q, bool clear_ctx_on_error = false; u64 alloc_time_ns = 0; - blk_queue_enter_live(q); - /* alloc_time includes depth and tag waits */ if (blk_queue_rq_alloc_time(q)) alloc_time_ns = ktime_get_ns(); @@ -379,7 +377,6 @@ static struct request *blk_mq_get_request(struct request_queue *q, if (tag == BLK_MQ_TAG_FAIL) { if (clear_ctx_on_error) data->ctx = NULL; - blk_queue_exit(q); return NULL; } @@ -409,16 +406,19 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, if (ret) return ERR_PTR(ret); + blk_queue_enter_live(q); rq = blk_mq_get_request(q, NULL, &alloc_data); blk_queue_exit(q); if (!rq) - return ERR_PTR(-EWOULDBLOCK); - + goto out_queue_exit; rq->__data_len = 0; rq->__sector = (sector_t) -1; rq->bio = rq->biotail = NULL; return rq; +out_queue_exit: + blk_queue_exit(q); + return ERR_PTR(-EWOULDBLOCK); } EXPORT_SYMBOL(blk_mq_alloc_request); @@ -450,21 +450,24 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, * Check if the hardware context is actually mapped to anything. * If not tell the caller that it should skip this queue. */ + ret = -EXDEV; alloc_data.hctx = q->queue_hw_ctx[hctx_idx]; - if (!blk_mq_hw_queue_mapped(alloc_data.hctx)) { - blk_queue_exit(q); - return ERR_PTR(-EXDEV); - } + if (!blk_mq_hw_queue_mapped(alloc_data.hctx)) + goto out_queue_exit; cpu = cpumask_first_and(alloc_data.hctx->cpumask, cpu_online_mask); alloc_data.ctx = __blk_mq_get_ctx(q, cpu); + ret = -EWOULDBLOCK; + blk_queue_enter_live(q); rq = blk_mq_get_request(q, NULL, &alloc_data); blk_queue_exit(q); if (!rq) - return ERR_PTR(-EWOULDBLOCK); - + goto out_queue_exit; return rq; +out_queue_exit: + blk_queue_exit(q); + return ERR_PTR(ret); } EXPORT_SYMBOL_GPL(blk_mq_alloc_request_hctx); @@ -2043,8 +2046,10 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) rq_qos_throttle(q, bio); data.cmd_flags = bio->bi_opf; + blk_queue_enter_live(q); rq = blk_mq_get_request(q, bio, &data); if (unlikely(!rq)) { + blk_queue_exit(q); rq_qos_cleanup(q, bio); if (bio->bi_opf & REQ_NOWAIT) bio_wouldblock_error(bio); -- cgit v1.2.3 From 22fa792cd8c67958adbddc9d436b850e148a623b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 16 May 2020 20:27:59 +0200 Subject: blk-mq: remove a pointless queue enter pair in blk_mq_alloc_request No need for two queue references. Signed-off-by: Christoph Hellwig Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/blk-mq.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index b7e06673a30b..4e62b97dceb4 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -406,10 +406,7 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, if (ret) return ERR_PTR(ret); - blk_queue_enter_live(q); rq = blk_mq_get_request(q, NULL, &alloc_data); - blk_queue_exit(q); - if (!rq) goto out_queue_exit; rq->__data_len = 0; -- cgit v1.2.3 From 35b371ff01410ec7c73312f1c1c320de35fcfd0f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 16 May 2020 20:28:00 +0200 Subject: blk-mq: remove a pointless queue enter pair in blk_mq_alloc_request_hctx No need for two queue references. Signed-off-by: Christoph Hellwig Reviewed-by: Bart Van Assche Signed-off-by: Jens Axboe --- block/blk-mq.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 4e62b97dceb4..b1c12de8926e 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -455,10 +455,7 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, alloc_data.ctx = __blk_mq_get_ctx(q, cpu); ret = -EWOULDBLOCK; - blk_queue_enter_live(q); rq = blk_mq_get_request(q, NULL, &alloc_data); - blk_queue_exit(q); - if (!rq) goto out_queue_exit; return rq; -- cgit v1.2.3 From ac7c5675fa45a372fab27d78a72d2e10e4734959 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Sat, 16 May 2020 20:28:01 +0200 Subject: blk-mq: allow blk_mq_make_request to consume the q_usage_counter reference blk_mq_make_request currently needs to grab an q_usage_counter reference when allocating a request. This is because the block layer grabs one before calling blk_mq_make_request, but also releases it as soon as blk_mq_make_request returns. Remove the blk_queue_exit call after blk_mq_make_request returns, and instead let it consume the reference. This works perfectly fine for the block layer caller, just device mapper needs an extra reference as the old problem still persists there. Open code blk_queue_enter_live in device mapper, as there should be no other callers and this allows better documenting why we do a non-try get. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 33 ++++++++++++++++++++------------- block/blk-mq.c | 13 +++++++------ block/blk.h | 11 ----------- drivers/md/dm.c | 11 ++++++++++- 4 files changed, 37 insertions(+), 31 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 1e97f9973523..78683ea61c93 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1066,6 +1066,20 @@ end_io: return false; } +static blk_qc_t do_make_request(struct bio *bio) +{ + struct request_queue *q = bio->bi_disk->queue; + blk_qc_t ret = BLK_QC_T_NONE; + + if (blk_crypto_bio_prep(&bio)) { + if (!q->make_request_fn) + return blk_mq_make_request(q, bio); + ret = q->make_request_fn(q, bio); + } + blk_queue_exit(q); + return ret; +} + /** * generic_make_request - re-submit a bio to the block device layer for I/O * @bio: The bio describing the location in memory and on the device. @@ -1131,14 +1145,7 @@ blk_qc_t generic_make_request(struct bio *bio) /* Create a fresh bio_list for all subordinate requests */ bio_list_on_stack[1] = bio_list_on_stack[0]; bio_list_init(&bio_list_on_stack[0]); - if (blk_crypto_bio_prep(&bio)) { - if (q->make_request_fn) - ret = q->make_request_fn(q, bio); - else - ret = blk_mq_make_request(q, bio); - } - - blk_queue_exit(q); + ret = do_make_request(bio); /* sort new bios into those for a lower level * and those for the same level @@ -1175,7 +1182,6 @@ EXPORT_SYMBOL(generic_make_request); blk_qc_t direct_make_request(struct bio *bio) { struct request_queue *q = bio->bi_disk->queue; - blk_qc_t ret = BLK_QC_T_NONE; if (WARN_ON_ONCE(q->make_request_fn)) { bio_io_error(bio); @@ -1185,10 +1191,11 @@ blk_qc_t direct_make_request(struct bio *bio) return BLK_QC_T_NONE; if (unlikely(bio_queue_enter(bio))) return BLK_QC_T_NONE; - if (blk_crypto_bio_prep(&bio)) - ret = blk_mq_make_request(q, bio); - blk_queue_exit(q); - return ret; + if (!blk_crypto_bio_prep(&bio)) { + blk_queue_exit(q); + return BLK_QC_T_NONE; + } + return blk_mq_make_request(q, bio); } EXPORT_SYMBOL_GPL(direct_make_request); diff --git a/block/blk-mq.c b/block/blk-mq.c index b1c12de8926e..cac11945f602 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -2028,26 +2028,24 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) __blk_queue_split(q, &bio, &nr_segs); if (!bio_integrity_prep(bio)) - return BLK_QC_T_NONE; + goto queue_exit; if (!is_flush_fua && !blk_queue_nomerges(q) && blk_attempt_plug_merge(q, bio, nr_segs, &same_queue_rq)) - return BLK_QC_T_NONE; + goto queue_exit; if (blk_mq_sched_bio_merge(q, bio, nr_segs)) - return BLK_QC_T_NONE; + goto queue_exit; rq_qos_throttle(q, bio); data.cmd_flags = bio->bi_opf; - blk_queue_enter_live(q); rq = blk_mq_get_request(q, bio, &data); if (unlikely(!rq)) { - blk_queue_exit(q); rq_qos_cleanup(q, bio); if (bio->bi_opf & REQ_NOWAIT) bio_wouldblock_error(bio); - return BLK_QC_T_NONE; + goto queue_exit; } trace_block_getrq(q, bio, bio->bi_opf); @@ -2134,6 +2132,9 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) } return cookie; +queue_exit: + blk_queue_exit(q); + return BLK_QC_T_NONE; } EXPORT_SYMBOL_GPL(blk_mq_make_request); /* only for request based dm */ diff --git a/block/blk.h b/block/blk.h index fc00537026a0..9e6ed5f11823 100644 --- a/block/blk.h +++ b/block/blk.h @@ -64,17 +64,6 @@ void blk_free_flush_queue(struct blk_flush_queue *q); void blk_freeze_queue(struct request_queue *q); -static inline void blk_queue_enter_live(struct request_queue *q) -{ - /* - * Given that running in generic_make_request() context - * guarantees that a live reference against q_usage_counter has - * been established, further references under that same context - * need not check that the queue has been frozen (marked dead). - */ - percpu_ref_get(&q->q_usage_counter); -} - static inline bool biovec_phys_mergeable(struct request_queue *q, struct bio_vec *vec1, struct bio_vec *vec2) { diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 8921cd79422c..f215b8666448 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1791,8 +1791,17 @@ static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio) int srcu_idx; struct dm_table *map; - if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) + if (dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) { + /* + * We are called with a live reference on q_usage_counter, but + * that one will be released as soon as we return. Grab an + * extra one as blk_mq_make_request expects to be able to + * consume a reference (which lives until the request is freed + * in case a request is allocated). + */ + percpu_ref_get(&q->q_usage_counter); return blk_mq_make_request(q, bio); + } map = dm_get_live_table(md, &srcu_idx); -- cgit v1.2.3 From f1394b79881458c3cfb12c1cac813085549f2c7d Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 May 2020 12:49:32 +0200 Subject: block: mark blk_account_io_completion static Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 2 +- block/blk.h | 1 - 2 files changed, 1 insertion(+), 2 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 78683ea61c93..d8df56e9bffb 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1381,7 +1381,7 @@ unsigned int blk_rq_err_bytes(const struct request *rq) } EXPORT_SYMBOL_GPL(blk_rq_err_bytes); -void blk_account_io_completion(struct request *req, unsigned int bytes) +static void blk_account_io_completion(struct request *req, unsigned int bytes) { if (req->part && blk_do_io_stat(req)) { const int sgrp = op_stat_group(req_op(req)); diff --git a/block/blk.h b/block/blk.h index 9e6ed5f11823..eb09216b533a 100644 --- a/block/blk.h +++ b/block/blk.h @@ -187,7 +187,6 @@ bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, unsigned int nr_segs, struct request **same_queue_rq); void blk_account_io_start(struct request *req, bool new_io); -void blk_account_io_completion(struct request *req, unsigned int bytes); void blk_account_io_done(struct request *req, u64 now); /* -- cgit v1.2.3 From b2f609e191edc9c7a9dec603318461eeb23f8a6b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 May 2020 12:49:33 +0200 Subject: block: move the blk-mq calls out of part_in_flight{,_rw} Don't bother to call part_in_flight / part_in_flight_rw on blk-mq devices, just call the blk-mq versions directly. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/genhd.c | 28 ++++++++++++++-------------- 1 file changed, 14 insertions(+), 14 deletions(-) (limited to 'block') diff --git a/block/genhd.c b/block/genhd.c index afdb2c3e5b22..56e0560738c4 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -142,14 +142,9 @@ void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw) static unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) { + unsigned int inflight = 0; int cpu; - unsigned int inflight; - - if (queue_is_mq(q)) { - return blk_mq_in_flight(q, part); - } - inflight = 0; for_each_possible_cpu(cpu) { inflight += part_stat_local_read_cpu(part, in_flight[0], cpu) + part_stat_local_read_cpu(part, in_flight[1], cpu); @@ -165,11 +160,6 @@ static void part_in_flight_rw(struct request_queue *q, struct hd_struct *part, { int cpu; - if (queue_is_mq(q)) { - blk_mq_in_flight_rw(q, part, inflight); - return; - } - inflight[0] = 0; inflight[1] = 0; for_each_possible_cpu(cpu) { @@ -1307,7 +1297,10 @@ ssize_t part_stat_show(struct device *dev, unsigned int inflight; part_stat_read_all(p, &stat); - inflight = part_in_flight(q, p); + if (queue_is_mq(q)) + inflight = blk_mq_in_flight(q, p); + else + inflight = part_in_flight(q, p); return sprintf(buf, "%8lu %8lu %8llu %8u " @@ -1346,7 +1339,11 @@ ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr, struct request_queue *q = part_to_disk(p)->queue; unsigned int inflight[2]; - part_in_flight_rw(q, p, inflight); + if (queue_is_mq(q)) + blk_mq_in_flight_rw(q, p, inflight); + else + part_in_flight_rw(q, p, inflight); + return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]); } @@ -1601,7 +1598,10 @@ static int diskstats_show(struct seq_file *seqf, void *v) disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0); while ((hd = disk_part_iter_next(&piter))) { part_stat_read_all(hd, &stat); - inflight = part_in_flight(gp->queue, hd); + if (queue_is_mq(gp->queue)) + inflight = blk_mq_in_flight(gp->queue, hd); + else + inflight = part_in_flight(gp->queue, hd); seq_printf(seqf, "%4d %7d %s " "%lu %lu %lu %u " -- cgit v1.2.3 From 76268f3ac0a69e76270af5f67ab239ccd796ae56 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 May 2020 12:49:34 +0200 Subject: block: don't call part_{inc,dec}_in_flight for blk-mq devices part_inc_in_flight and part_dec_in_flight are no-ops for blk-mq queues, so remove the calls in purely blk-mq callers. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 21 +++++---------------- block/blk-merge.c | 2 -- 2 files changed, 5 insertions(+), 18 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index d8df56e9bffb..77e57c2e8d60 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1412,7 +1412,6 @@ void blk_account_io_done(struct request *req, u64 now) update_io_ticks(part, jiffies, true); part_stat_inc(part, ios[sgrp]); part_stat_add(part, nsecs[sgrp], now - req->start_time_ns); - part_dec_in_flight(req->q, part, rq_data_dir(req)); hd_struct_put(part); part_stat_unlock(); @@ -1421,25 +1420,15 @@ void blk_account_io_done(struct request *req, u64 now) void blk_account_io_start(struct request *rq, bool new_io) { - struct hd_struct *part; - int rw = rq_data_dir(rq); - if (!blk_do_io_stat(rq)) return; part_stat_lock(); - - if (!new_io) { - part = rq->part; - part_stat_inc(part, merges[rw]); - } else { - part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); - part_inc_in_flight(rq->q, part, rw); - rq->part = part; - } - - update_io_ticks(part, jiffies, false); - + if (!new_io) + part_stat_inc(rq->part, merges[rq_data_dir(rq)]); + else + rq->part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); + update_io_ticks(rq->part, jiffies, false); part_stat_unlock(); } diff --git a/block/blk-merge.c b/block/blk-merge.c index 1a9036398214..6a4538d39efd 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -677,8 +677,6 @@ static void blk_account_io_merge(struct request *req) part_stat_lock(); part = req->part; - part_dec_in_flight(req->q, part, rq_data_dir(req)); - hd_struct_put(part); part_stat_unlock(); } -- cgit v1.2.3 From 10ec5e86f9b840b7070b9146257a199dd0227d7e Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 May 2020 12:49:35 +0200 Subject: block: merge part_{inc,dev}_in_flight into their only callers part_inc_in_flight and part_dec_in_flight only have one caller each, and those callers are purely for bio based drivers. Merge each function into the only caller, and remove the superflous blk-mq checks. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/bio.c | 10 ++++++++-- block/blk.h | 4 ---- block/genhd.c | 20 -------------------- 3 files changed, 8 insertions(+), 26 deletions(-) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index 1594804fe8bc..9c101a0572ca 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1396,13 +1396,16 @@ void generic_start_io_acct(struct request_queue *q, int op, unsigned long sectors, struct hd_struct *part) { const int sgrp = op_stat_group(op); + int rw = op_is_write(op); part_stat_lock(); update_io_ticks(part, jiffies, false); part_stat_inc(part, ios[sgrp]); part_stat_add(part, sectors[sgrp], sectors); - part_inc_in_flight(q, part, op_is_write(op)); + part_stat_local_inc(part, in_flight[rw]); + if (part->partno) + part_stat_local_inc(&part_to_disk(part)->part0, in_flight[rw]); part_stat_unlock(); } @@ -1414,12 +1417,15 @@ void generic_end_io_acct(struct request_queue *q, int req_op, unsigned long now = jiffies; unsigned long duration = now - start_time; const int sgrp = op_stat_group(req_op); + int rw = op_is_write(req_op); part_stat_lock(); update_io_ticks(part, now, true); part_stat_add(part, nsecs[sgrp], jiffies_to_nsecs(duration)); - part_dec_in_flight(q, part, op_is_write(req_op)); + part_stat_local_dec(part, in_flight[rw]); + if (part->partno) + part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]); part_stat_unlock(); } diff --git a/block/blk.h b/block/blk.h index eb09216b533a..af11fd400c72 100644 --- a/block/blk.h +++ b/block/blk.h @@ -345,10 +345,6 @@ void blk_queue_free_zone_bitmaps(struct request_queue *q); static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {} #endif -void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, - int rw); -void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, - int rw); void update_io_ticks(struct hd_struct *part, unsigned long now, bool end); struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector); diff --git a/block/genhd.c b/block/genhd.c index 56e0560738c4..094ed9096496 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -119,26 +119,6 @@ static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) } #endif /* CONFIG_SMP */ -void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, int rw) -{ - if (queue_is_mq(q)) - return; - - part_stat_local_inc(part, in_flight[rw]); - if (part->partno) - part_stat_local_inc(&part_to_disk(part)->part0, in_flight[rw]); -} - -void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, int rw) -{ - if (queue_is_mq(q)) - return; - - part_stat_local_dec(part, in_flight[rw]); - if (part->partno) - part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]); -} - static unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) { -- cgit v1.2.3 From c8210a57655a64c0a9b53c58c2ad5d8426c15097 Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Mon, 18 May 2020 21:07:34 -0700 Subject: block: Fix type of first compat_put_{,u}long() argument This patch fixes the following sparse warnings: block/ioctl.c:209:16: warning: incorrect type in argument 1 (different address spaces) block/ioctl.c:209:16: expected void const volatile [noderef] * block/ioctl.c:209:16: got signed int [usertype] *argp block/ioctl.c:214:16: warning: incorrect type in argument 1 (different address spaces) block/ioctl.c:214:16: expected void const volatile [noderef] * block/ioctl.c:214:16: got unsigned int [usertype] *argp block/ioctl.c:666:40: warning: incorrect type in argument 1 (different address spaces) block/ioctl.c:666:40: expected signed int [usertype] *argp block/ioctl.c:666:40: got void [noderef] *argp block/ioctl.c:672:41: warning: incorrect type in argument 1 (different address spaces) block/ioctl.c:672:41: expected unsigned int [usertype] *argp block/ioctl.c:672:41: got void [noderef] *argp Fixes: 9b81648cb5e3 ("compat_ioctl: simplify up block/ioctl.c") Signed-off-by: Bart Van Assche Reviewed-by: Christoph Hellwig Acked-by: Arnd Bergmann Cc: Arnd Bergmann Signed-off-by: Jens Axboe --- block/ioctl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/ioctl.c b/block/ioctl.c index 75c64811b534..bdb3bbb253d9 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -204,12 +204,12 @@ static int put_u64(u64 __user *argp, u64 val) } #ifdef CONFIG_COMPAT -static int compat_put_long(compat_long_t *argp, long val) +static int compat_put_long(compat_long_t __user *argp, long val) { return put_user(val, argp); } -static int compat_put_ulong(compat_ulong_t *argp, compat_ulong_t val) +static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val) { return put_user(val, argp); } -- cgit v1.2.3 From 172ce41db4b2d6fa5956c4baa63475b15f5d4bd8 Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Sun, 17 May 2020 19:49:41 +0800 Subject: block: Remove unused flush_queue_delayed in struct blk_flush_queue The flush_queue_delayed was introdued to hold queue if flush is running for non-queueable flush drive by commit 3ac0cc450870 ("hold queue if flush is running for non-queueable flush drive"), but the non mq parts of the flush code had been removed by commit 7e992f847a08 ("block: remove non mq parts from the flush code"), as well as removing the usage of the flush_queue_delayed flag. Thus remove the unused flush_queue_delayed flag. Signed-off-by: Baolin Wang Reviewed-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-flush.c | 1 - block/blk.h | 1 - 2 files changed, 2 deletions(-) (limited to 'block') diff --git a/block/blk-flush.c b/block/blk-flush.c index c7f396e3d5e2..b733f7ac75c7 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -258,7 +258,6 @@ static void flush_end_io(struct request *flush_rq, blk_status_t error) blk_flush_complete_seq(rq, fq, seq, error); } - fq->flush_queue_delayed = 0; spin_unlock_irqrestore(&fq->mq_flush_lock, flags); } diff --git a/block/blk.h b/block/blk.h index af11fd400c72..5db4ec1e85f7 100644 --- a/block/blk.h +++ b/block/blk.h @@ -19,7 +19,6 @@ extern struct dentry *blk_debugfs_root; #endif struct blk_flush_queue { - unsigned int flush_queue_delayed:1; unsigned int flush_pending_idx:1; unsigned int flush_running_idx:1; blk_status_t rq_status; -- cgit v1.2.3 From 9398554fb3979852512ff4f1405e759889b45c16 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 May 2020 14:36:00 +0200 Subject: block: remove the error_sector argument to blkdev_issue_flush The argument isn't used by any caller, and drivers don't fill out bi_sector for flush requests either. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-flush.c | 17 ++--------------- drivers/md/dm-integrity.c | 2 +- drivers/md/dm-zoned-metadata.c | 6 +++--- drivers/md/raid5-ppl.c | 2 +- drivers/nvme/target/io-cmd-bdev.c | 2 +- fs/block_dev.c | 2 +- fs/ext4/fsync.c | 2 +- fs/ext4/ialloc.c | 2 +- fs/ext4/super.c | 2 +- fs/fat/file.c | 2 +- fs/hfsplus/inode.c | 2 +- fs/hfsplus/super.c | 2 +- fs/jbd2/checkpoint.c | 2 +- fs/jbd2/commit.c | 4 ++-- fs/jbd2/recovery.c | 2 +- fs/libfs.c | 2 +- fs/nilfs2/the_nilfs.h | 2 +- fs/ocfs2/file.c | 2 +- fs/reiserfs/file.c | 2 +- fs/xfs/xfs_super.c | 2 +- fs/zonefs/super.c | 2 +- include/linux/blkdev.h | 5 ++--- 22 files changed, 27 insertions(+), 41 deletions(-) (limited to 'block') diff --git a/block/blk-flush.c b/block/blk-flush.c index b733f7ac75c7..d47a579964fb 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -432,15 +432,11 @@ void blk_insert_flush(struct request *rq) * blkdev_issue_flush - queue a flush * @bdev: blockdev to issue flush for * @gfp_mask: memory allocation flags (for bio_alloc) - * @error_sector: error sector * * Description: - * Issue a flush for the block device in question. Caller can supply - * room for storing the error offset in case of a flush error, if they - * wish to. + * Issue a flush for the block device in question. */ -int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, - sector_t *error_sector) +int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask) { struct request_queue *q; struct bio *bio; @@ -458,15 +454,6 @@ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; ret = submit_bio_wait(bio); - - /* - * The driver must store the error location in ->bi_sector, if - * it supports it. For non-stacked drivers, this should be - * copied from blk_rq_pos(rq). - */ - if (error_sector) - *error_sector = bio->bi_iter.bi_sector; - bio_put(bio); return ret; } diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 4094c47eca7f..84cb04904fab 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -2657,7 +2657,7 @@ static void bitmap_flush_work(struct work_struct *work) dm_integrity_flush_buffers(ic); if (ic->meta_dev) - blkdev_issue_flush(ic->dev->bdev, GFP_NOIO, NULL); + blkdev_issue_flush(ic->dev->bdev, GFP_NOIO); limit = ic->provided_data_sectors; if (ic->sb->flags & cpu_to_le32(SB_FLAG_RECALCULATING)) { diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c index 369de15c4e80..bf2245370305 100644 --- a/drivers/md/dm-zoned-metadata.c +++ b/drivers/md/dm-zoned-metadata.c @@ -661,7 +661,7 @@ static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set) ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page); if (ret == 0) - ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO); return ret; } @@ -703,7 +703,7 @@ static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd, /* Flush drive cache (this will also sync data) */ if (ret == 0) - ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO); return ret; } @@ -772,7 +772,7 @@ int dmz_flush_metadata(struct dmz_metadata *zmd) /* If there are no dirty metadata blocks, just flush the device cache */ if (list_empty(&write_list)) { - ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO); goto err; } diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c index d50238d0a85d..a750f4bbb5d9 100644 --- a/drivers/md/raid5-ppl.c +++ b/drivers/md/raid5-ppl.c @@ -1037,7 +1037,7 @@ static int ppl_recover(struct ppl_log *log, struct ppl_header *pplhdr, } /* flush the disk cache after recovery if necessary */ - ret = blkdev_issue_flush(rdev->bdev, GFP_KERNEL, NULL); + ret = blkdev_issue_flush(rdev->bdev, GFP_KERNEL); out: __free_page(page); return ret; diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c index ea0e596be15d..26f50c23b82e 100644 --- a/drivers/nvme/target/io-cmd-bdev.c +++ b/drivers/nvme/target/io-cmd-bdev.c @@ -226,7 +226,7 @@ static void nvmet_bdev_execute_flush(struct nvmet_req *req) u16 nvmet_bdev_flush(struct nvmet_req *req) { - if (blkdev_issue_flush(req->ns->bdev, GFP_KERNEL, NULL)) + if (blkdev_issue_flush(req->ns->bdev, GFP_KERNEL)) return NVME_SC_INTERNAL | NVME_SC_DNR; return 0; } diff --git a/fs/block_dev.c b/fs/block_dev.c index ebd1507789d2..d1e08bba925a 100644 --- a/fs/block_dev.c +++ b/fs/block_dev.c @@ -672,7 +672,7 @@ int blkdev_fsync(struct file *filp, loff_t start, loff_t end, int datasync) * i_mutex and doing so causes performance issues with concurrent * O_SYNC writers to a block device. */ - error = blkdev_issue_flush(bdev, GFP_KERNEL, NULL); + error = blkdev_issue_flush(bdev, GFP_KERNEL); if (error == -EOPNOTSUPP) error = 0; diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c index e10206e7f4bb..35ff9a56db67 100644 --- a/fs/ext4/fsync.c +++ b/fs/ext4/fsync.c @@ -176,7 +176,7 @@ int ext4_sync_file(struct file *file, loff_t start, loff_t end, int datasync) ret = ext4_fsync_journal(inode, datasync, &needs_barrier); if (needs_barrier) { - err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + err = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); if (!ret) ret = err; } diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 4b8c9a9bdf0c..499f08d8522e 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -1440,7 +1440,7 @@ int ext4_init_inode_table(struct super_block *sb, ext4_group_t group, if (ret < 0) goto err_out; if (barrier) - blkdev_issue_flush(sb->s_bdev, GFP_NOFS, NULL); + blkdev_issue_flush(sb->s_bdev, GFP_NOFS); skip_zeroout: ext4_lock_group(sb, group); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index bf5fcb477f66..629a56b5c859 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5256,7 +5256,7 @@ static int ext4_sync_fs(struct super_block *sb, int wait) needs_barrier = true; if (needs_barrier) { int err; - err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL); + err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL); if (!ret) ret = err; } diff --git a/fs/fat/file.c b/fs/fat/file.c index bdc4503c00a3..42134c58c87e 100644 --- a/fs/fat/file.c +++ b/fs/fat/file.c @@ -195,7 +195,7 @@ int fat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync) if (err) return err; - return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); } diff --git a/fs/hfsplus/inode.c b/fs/hfsplus/inode.c index 94bd83b36644..e3da9e96b835 100644 --- a/fs/hfsplus/inode.c +++ b/fs/hfsplus/inode.c @@ -340,7 +340,7 @@ int hfsplus_file_fsync(struct file *file, loff_t start, loff_t end, } if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags)) - blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); inode_unlock(inode); diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c index 2b9e5743105e..129dca3f4b78 100644 --- a/fs/hfsplus/super.c +++ b/fs/hfsplus/super.c @@ -239,7 +239,7 @@ out: mutex_unlock(&sbi->vh_mutex); if (!test_bit(HFSPLUS_SB_NOBARRIER, &sbi->flags)) - blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL); + blkdev_issue_flush(sb->s_bdev, GFP_KERNEL); return error; } diff --git a/fs/jbd2/checkpoint.c b/fs/jbd2/checkpoint.c index 96bf33986d03..263f02ad8ebf 100644 --- a/fs/jbd2/checkpoint.c +++ b/fs/jbd2/checkpoint.c @@ -414,7 +414,7 @@ int jbd2_cleanup_journal_tail(journal_t *journal) * jbd2_cleanup_journal_tail() doesn't get called all that often. */ if (journal->j_flags & JBD2_BARRIER) - blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS, NULL); + blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS); return __jbd2_update_log_tail(journal, first_tid, blocknr); } diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index e855d8260433..6d2da8ad0e6f 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -775,7 +775,7 @@ start_journal_io: if (commit_transaction->t_need_data_flush && (journal->j_fs_dev != journal->j_dev) && (journal->j_flags & JBD2_BARRIER)) - blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS, NULL); + blkdev_issue_flush(journal->j_fs_dev, GFP_NOFS); /* Done it all: now write the commit record asynchronously. */ if (jbd2_has_feature_async_commit(journal)) { @@ -882,7 +882,7 @@ start_journal_io: stats.run.rs_blocks_logged++; if (jbd2_has_feature_async_commit(journal) && journal->j_flags & JBD2_BARRIER) { - blkdev_issue_flush(journal->j_dev, GFP_NOFS, NULL); + blkdev_issue_flush(journal->j_dev, GFP_NOFS); } if (err) diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c index a4967b27ffb6..2ed278f0dced 100644 --- a/fs/jbd2/recovery.c +++ b/fs/jbd2/recovery.c @@ -286,7 +286,7 @@ int jbd2_journal_recover(journal_t *journal) err = err2; /* Make sure all replayed data is on permanent storage */ if (journal->j_flags & JBD2_BARRIER) { - err2 = blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL, NULL); + err2 = blkdev_issue_flush(journal->j_fs_dev, GFP_KERNEL); if (!err) err = err2; } diff --git a/fs/libfs.c b/fs/libfs.c index 3759fbacf522..4d08edf19c78 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1113,7 +1113,7 @@ int generic_file_fsync(struct file *file, loff_t start, loff_t end, err = __generic_file_fsync(file, start, end, datasync); if (err) return err; - return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); } EXPORT_SYMBOL(generic_file_fsync); diff --git a/fs/nilfs2/the_nilfs.h b/fs/nilfs2/the_nilfs.h index 380a543c5b19..b55cdeb4d169 100644 --- a/fs/nilfs2/the_nilfs.h +++ b/fs/nilfs2/the_nilfs.h @@ -375,7 +375,7 @@ static inline int nilfs_flush_device(struct the_nilfs *nilfs) */ smp_wmb(); - err = blkdev_issue_flush(nilfs->ns_bdev, GFP_KERNEL, NULL); + err = blkdev_issue_flush(nilfs->ns_bdev, GFP_KERNEL); if (err != -EIO) err = 0; return err; diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index 6cd5e4924e4d..85979e2214b3 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -194,7 +194,7 @@ static int ocfs2_sync_file(struct file *file, loff_t start, loff_t end, needs_barrier = true; err = jbd2_complete_transaction(journal, commit_tid); if (needs_barrier) { - ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); if (!err) err = ret; } diff --git a/fs/reiserfs/file.c b/fs/reiserfs/file.c index 84cf8bdbec9c..0b641ae694f1 100644 --- a/fs/reiserfs/file.c +++ b/fs/reiserfs/file.c @@ -159,7 +159,7 @@ static int reiserfs_sync_file(struct file *filp, loff_t start, loff_t end, barrier_done = reiserfs_commit_for_inode(inode); reiserfs_write_unlock(inode->i_sb); if (barrier_done != 1 && reiserfs_barrier_flush(inode->i_sb)) - blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); inode_unlock(inode); if (barrier_done < 0) return barrier_done; diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 424bb9a2d532..a123cd8267d9 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -305,7 +305,7 @@ void xfs_blkdev_issue_flush( xfs_buftarg_t *buftarg) { - blkdev_issue_flush(buftarg->bt_bdev, GFP_NOFS, NULL); + blkdev_issue_flush(buftarg->bt_bdev, GFP_NOFS); } STATIC void diff --git a/fs/zonefs/super.c b/fs/zonefs/super.c index 0bf7009f50a2..25afcf55aa41 100644 --- a/fs/zonefs/super.c +++ b/fs/zonefs/super.c @@ -479,7 +479,7 @@ static int zonefs_file_fsync(struct file *file, loff_t start, loff_t end, if (ZONEFS_I(inode)->i_ztype == ZONEFS_ZTYPE_CNV) ret = file_write_and_wait_range(file, start, end); if (!ret) - ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); + ret = blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL); if (ret) zonefs_io_error(inode, true); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 2b33166b9daf..7d10f4e63232 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1233,7 +1233,7 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk) extern void blk_io_schedule(void); -extern int blkdev_issue_flush(struct block_device *, gfp_t, sector_t *); +int blkdev_issue_flush(struct block_device *, gfp_t); extern int blkdev_issue_write_same(struct block_device *bdev, sector_t sector, sector_t nr_sects, gfp_t gfp_mask, struct page *page); @@ -1872,8 +1872,7 @@ static inline bool blk_needs_flush_plug(struct task_struct *tsk) return false; } -static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask, - sector_t *error_sector) +static inline int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask) { return 0; } -- cgit v1.2.3 From c81b49d4d6ca3876fad42fe99e685605294f757c Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 13 May 2020 14:36:01 +0200 Subject: block: remove the disk and queue NULL checks in blkdev_issue_flush Both of these never can be NULL for a live block device. Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-flush.c | 8 -------- 1 file changed, 8 deletions(-) (limited to 'block') diff --git a/block/blk-flush.c b/block/blk-flush.c index d47a579964fb..15ae0155ec07 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -438,17 +438,9 @@ void blk_insert_flush(struct request *rq) */ int blkdev_issue_flush(struct block_device *bdev, gfp_t gfp_mask) { - struct request_queue *q; struct bio *bio; int ret = 0; - if (bdev->bd_disk == NULL) - return -ENXIO; - - q = bdev_get_queue(bdev); - if (!q) - return -ENXIO; - bio = bio_alloc(gfp_mask, 0); bio_set_dev(bio, bdev); bio->bi_opf = REQ_OP_WRITE | REQ_PREFLUSH; -- cgit v1.2.3 From 956d510ee78caebc83c0eaeb892db5b239a36a06 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 27 May 2020 07:24:04 +0200 Subject: block: add disk/bio-based accounting helpers Add two new helpers to simplify I/O accounting for bio based drivers. Currently these drivers use the generic_start_io_acct and generic_end_io_acct helpers which have very cumbersome calling conventions, don't actually return the time they started accounting, and try to deal with accounting for partitions, which can't happen for bio based drivers. The new helpers will be used to subsequently replace uses of the old helpers. The main API is the bio based wrappes in blkdev.h, but for zram which wants to account rw_page based I/O lower level routines are provided as well. Signed-off-by: Christoph Hellwig Reviewed-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe --- block/blk-core.c | 34 ++++++++++++++++++++++++++++++++++ include/linux/blkdev.h | 28 ++++++++++++++++++++++++++++ 2 files changed, 62 insertions(+) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index 77e57c2e8d60..8973104f88d9 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1432,6 +1432,40 @@ void blk_account_io_start(struct request *rq, bool new_io) part_stat_unlock(); } +unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors, + unsigned int op) +{ + struct hd_struct *part = &disk->part0; + const int sgrp = op_stat_group(op); + unsigned long now = READ_ONCE(jiffies); + + part_stat_lock(); + update_io_ticks(part, now, false); + part_stat_inc(part, ios[sgrp]); + part_stat_add(part, sectors[sgrp], sectors); + part_stat_local_inc(part, in_flight[op_is_write(op)]); + part_stat_unlock(); + + return now; +} +EXPORT_SYMBOL(disk_start_io_acct); + +void disk_end_io_acct(struct gendisk *disk, unsigned int op, + unsigned long start_time) +{ + struct hd_struct *part = &disk->part0; + const int sgrp = op_stat_group(op); + unsigned long now = READ_ONCE(jiffies); + unsigned long duration = now - start_time; + + part_stat_lock(); + update_io_ticks(part, now, true); + part_stat_add(part, nsecs[sgrp], jiffies_to_nsecs(duration)); + part_stat_local_dec(part, in_flight[op_is_write(op)]); + part_stat_unlock(); +} +EXPORT_SYMBOL(disk_end_io_acct); + /* * Steal bios from a request and add them to a bio list. * The request must not have been partially completed before. diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 7d10f4e63232..6f7ff0fa8fcf 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1892,4 +1892,32 @@ static inline void blk_wake_io_task(struct task_struct *waiter) wake_up_process(waiter); } +unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors, + unsigned int op); +void disk_end_io_acct(struct gendisk *disk, unsigned int op, + unsigned long start_time); + +#ifdef CONFIG_BLOCK +/** + * bio_start_io_acct - start I/O accounting for bio based drivers + * @bio: bio to start account for + * + * Returns the start time that should be passed back to bio_end_io_acct(). + */ +static inline unsigned long bio_start_io_acct(struct bio *bio) +{ + return disk_start_io_acct(bio->bi_disk, bio_sectors(bio), bio_op(bio)); +} + +/** + * bio_end_io_acct - end I/O accounting for bio based drivers + * @bio: bio to end account for + * @start: start time returned by bio_start_io_acct() + */ +static inline void bio_end_io_acct(struct bio *bio, unsigned long start_time) +{ + return disk_end_io_acct(bio->bi_disk, bio_op(bio), start_time); +} +#endif /* CONFIG_BLOCK */ + #endif -- cgit v1.2.3 From e722fff238bbfe6308d7778a8c2163c181bf998a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 27 May 2020 07:24:12 +0200 Subject: block: remove generic_{start,end}_io_acct Remove these now unused functions. Signed-off-by: Christoph Hellwig Reviewed-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe --- block/bio.c | 39 --------------------------------------- include/linux/bio.h | 6 ------ 2 files changed, 45 deletions(-) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index 9c101a0572ca..3e89c7b37855 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1392,45 +1392,6 @@ again: } } -void generic_start_io_acct(struct request_queue *q, int op, - unsigned long sectors, struct hd_struct *part) -{ - const int sgrp = op_stat_group(op); - int rw = op_is_write(op); - - part_stat_lock(); - - update_io_ticks(part, jiffies, false); - part_stat_inc(part, ios[sgrp]); - part_stat_add(part, sectors[sgrp], sectors); - part_stat_local_inc(part, in_flight[rw]); - if (part->partno) - part_stat_local_inc(&part_to_disk(part)->part0, in_flight[rw]); - - part_stat_unlock(); -} -EXPORT_SYMBOL(generic_start_io_acct); - -void generic_end_io_acct(struct request_queue *q, int req_op, - struct hd_struct *part, unsigned long start_time) -{ - unsigned long now = jiffies; - unsigned long duration = now - start_time; - const int sgrp = op_stat_group(req_op); - int rw = op_is_write(req_op); - - part_stat_lock(); - - update_io_ticks(part, now, true); - part_stat_add(part, nsecs[sgrp], jiffies_to_nsecs(duration)); - part_stat_local_dec(part, in_flight[rw]); - if (part->partno) - part_stat_local_dec(&part_to_disk(part)->part0, in_flight[rw]); - - part_stat_unlock(); -} -EXPORT_SYMBOL(generic_end_io_acct); - static inline bool bio_remaining_done(struct bio *bio) { /* diff --git a/include/linux/bio.h b/include/linux/bio.h index 950c9dc44c4f..941378ec5b39 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -444,12 +444,6 @@ void bio_release_pages(struct bio *bio, bool mark_dirty); extern void bio_set_pages_dirty(struct bio *bio); extern void bio_check_pages_dirty(struct bio *bio); -void generic_start_io_acct(struct request_queue *q, int op, - unsigned long sectors, struct hd_struct *part); -void generic_end_io_acct(struct request_queue *q, int op, - struct hd_struct *part, - unsigned long start_time); - extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, struct bio *src, struct bvec_iter *src_iter); extern void bio_copy_data(struct bio *dst, struct bio *src); -- cgit v1.2.3 From 9123bf6f21b015cce16f3ce066c72aac9fc78d2f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 27 May 2020 07:24:13 +0200 Subject: block: move update_io_ticks to blk-core.c All callers are in blk-core.c, so move update_io_ticks over. Signed-off-by: Christoph Hellwig Reviewed-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe --- block/bio.c | 16 ---------------- block/blk-core.c | 15 +++++++++++++++ block/blk.h | 1 - 3 files changed, 15 insertions(+), 17 deletions(-) (limited to 'block') diff --git a/block/bio.c b/block/bio.c index 3e89c7b37855..5235da6434aa 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1376,22 +1376,6 @@ defer: schedule_work(&bio_dirty_work); } -void update_io_ticks(struct hd_struct *part, unsigned long now, bool end) -{ - unsigned long stamp; -again: - stamp = READ_ONCE(part->stamp); - if (unlikely(stamp != now)) { - if (likely(cmpxchg(&part->stamp, stamp, now) == stamp)) { - __part_stat_add(part, io_ticks, end ? now - stamp : 1); - } - } - if (part->partno) { - part = &part_to_disk(part)->part0; - goto again; - } -} - static inline bool bio_remaining_done(struct bio *bio) { /* diff --git a/block/blk-core.c b/block/blk-core.c index 8973104f88d9..c1675d43c2da 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1381,6 +1381,21 @@ unsigned int blk_rq_err_bytes(const struct request *rq) } EXPORT_SYMBOL_GPL(blk_rq_err_bytes); +static void update_io_ticks(struct hd_struct *part, unsigned long now, bool end) +{ + unsigned long stamp; +again: + stamp = READ_ONCE(part->stamp); + if (unlikely(stamp != now)) { + if (likely(cmpxchg(&part->stamp, stamp, now) == stamp)) + __part_stat_add(part, io_ticks, end ? now - stamp : 1); + } + if (part->partno) { + part = &part_to_disk(part)->part0; + goto again; + } +} + static void blk_account_io_completion(struct request *req, unsigned int bytes) { if (req->part && blk_do_io_stat(req)) { diff --git a/block/blk.h b/block/blk.h index 5db4ec1e85f7..bdf5e94467aa 100644 --- a/block/blk.h +++ b/block/blk.h @@ -344,7 +344,6 @@ void blk_queue_free_zone_bitmaps(struct request_queue *q); static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {} #endif -void update_io_ticks(struct hd_struct *part, unsigned long now, bool end); struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector); int blk_alloc_devt(struct hd_struct *part, dev_t *devt); -- cgit v1.2.3 From 58d4f14fc30ac26288cfed74d7e566921c22cf59 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 27 May 2020 07:24:14 +0200 Subject: block: always use a percpu variable for disk stats percpu variables have a perfectly fine working stub implementation for UP kernels, so use that. Signed-off-by: Christoph Hellwig Reviewed-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe --- block/blk.h | 2 +- block/genhd.c | 12 +++-------- block/partitions/core.c | 5 +++-- include/linux/genhd.h | 13 ----------- include/linux/part_stat.h | 55 ++++++++++------------------------------------- 5 files changed, 18 insertions(+), 69 deletions(-) (limited to 'block') diff --git a/block/blk.h b/block/blk.h index bdf5e94467aa..0ecba2ab383d 100644 --- a/block/blk.h +++ b/block/blk.h @@ -378,7 +378,7 @@ static inline void hd_struct_put(struct hd_struct *part) static inline void hd_free_part(struct hd_struct *part) { - free_part_stats(part); + free_percpu(part->dkstats); kfree(part->info); percpu_ref_exit(&part->ref); } diff --git a/block/genhd.c b/block/genhd.c index 094ed9096496..3e7df0a3e6bb 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -92,7 +92,6 @@ const char *bdevname(struct block_device *bdev, char *buf) } EXPORT_SYMBOL(bdevname); -#ifdef CONFIG_SMP static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) { int cpu; @@ -112,12 +111,6 @@ static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) stat->io_ticks += ptr->io_ticks; } } -#else /* CONFIG_SMP */ -static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat) -{ - memcpy(stat, &part->dkstats, sizeof(struct disk_stats)); -} -#endif /* CONFIG_SMP */ static unsigned int part_in_flight(struct request_queue *q, struct hd_struct *part) @@ -1688,14 +1681,15 @@ struct gendisk *__alloc_disk_node(int minors, int node_id) disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); if (disk) { - if (!init_part_stats(&disk->part0)) { + disk->part0.dkstats = alloc_percpu(struct disk_stats); + if (!disk->part0.dkstats) { kfree(disk); return NULL; } init_rwsem(&disk->lookup_sem); disk->node_id = node_id; if (disk_expand_part_tbl(disk, 0)) { - free_part_stats(&disk->part0); + free_percpu(disk->part0.dkstats); kfree(disk); return NULL; } diff --git a/block/partitions/core.c b/block/partitions/core.c index 297004fd2264..78951e33b2d7 100644 --- a/block/partitions/core.c +++ b/block/partitions/core.c @@ -387,7 +387,8 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno, if (!p) return ERR_PTR(-EBUSY); - if (!init_part_stats(p)) { + p->dkstats = alloc_percpu(struct disk_stats); + if (!p->dkstats) { err = -ENOMEM; goto out_free; } @@ -468,7 +469,7 @@ static struct hd_struct *add_partition(struct gendisk *disk, int partno, out_free_info: kfree(p->info); out_free_stats: - free_part_stats(p); + free_percpu(p->dkstats); out_free: kfree(p); return ERR_PTR(err); diff --git a/include/linux/genhd.h b/include/linux/genhd.h index a9384449465a..f0d6d77309a5 100644 --- a/include/linux/genhd.h +++ b/include/linux/genhd.h @@ -39,15 +39,6 @@ extern struct class block_class; #include #include -struct disk_stats { - u64 nsecs[NR_STAT_GROUPS]; - unsigned long sectors[NR_STAT_GROUPS]; - unsigned long ios[NR_STAT_GROUPS]; - unsigned long merges[NR_STAT_GROUPS]; - unsigned long io_ticks; - local_t in_flight[2]; -}; - #define PARTITION_META_INFO_VOLNAMELTH 64 /* * Enough for the string representation of any kind of UUID plus NULL. @@ -72,11 +63,7 @@ struct hd_struct { seqcount_t nr_sects_seq; #endif unsigned long stamp; -#ifdef CONFIG_SMP struct disk_stats __percpu *dkstats; -#else - struct disk_stats dkstats; -#endif struct percpu_ref ref; sector_t alignment_offset; diff --git a/include/linux/part_stat.h b/include/linux/part_stat.h index ece607607a86..6644197980b9 100644 --- a/include/linux/part_stat.h +++ b/include/linux/part_stat.h @@ -4,19 +4,23 @@ #include +struct disk_stats { + u64 nsecs[NR_STAT_GROUPS]; + unsigned long sectors[NR_STAT_GROUPS]; + unsigned long ios[NR_STAT_GROUPS]; + unsigned long merges[NR_STAT_GROUPS]; + unsigned long io_ticks; + local_t in_flight[2]; +}; + /* * Macros to operate on percpu disk statistics: * - * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters - * and should be called between disk_stat_lock() and - * disk_stat_unlock(). + * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters and should + * be called between disk_stat_lock() and disk_stat_unlock(). * * part_stat_read() can be called at any time. - * - * part_stat_{add|set_all}() and {init|free}_part_stats are for - * internal use only. */ -#ifdef CONFIG_SMP #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); }) #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0) @@ -44,43 +48,6 @@ static inline void part_stat_set_all(struct hd_struct *part, int value) sizeof(struct disk_stats)); } -static inline int init_part_stats(struct hd_struct *part) -{ - part->dkstats = alloc_percpu(struct disk_stats); - if (!part->dkstats) - return 0; - return 1; -} - -static inline void free_part_stats(struct hd_struct *part) -{ - free_percpu(part->dkstats); -} - -#else /* !CONFIG_SMP */ -#define part_stat_lock() ({ rcu_read_lock(); 0; }) -#define part_stat_unlock() rcu_read_unlock() - -#define part_stat_get(part, field) ((part)->dkstats.field) -#define part_stat_get_cpu(part, field, cpu) part_stat_get(part, field) -#define part_stat_read(part, field) part_stat_get(part, field) - -static inline void part_stat_set_all(struct hd_struct *part, int value) -{ - memset(&part->dkstats, value, sizeof(struct disk_stats)); -} - -static inline int init_part_stats(struct hd_struct *part) -{ - return 1; -} - -static inline void free_part_stats(struct hd_struct *part) -{ -} - -#endif /* CONFIG_SMP */ - #define part_stat_read_accum(part, field) \ (part_stat_read(part, field[STAT_READ]) + \ part_stat_read(part, field[STAT_WRITE]) + \ -- cgit v1.2.3 From b9c54f5660e7eff10dd2ddd1eae554573105b15d Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Wed, 27 May 2020 07:24:15 +0200 Subject: block: account merge of two requests Also rename blk_account_io_merge() into blk_account_io_merge_request() to distinguish it from merging request and bio. [hch: rebased] Signed-off-by: Konstantin Khlebnikov Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-merge.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'block') diff --git a/block/blk-merge.c b/block/blk-merge.c index 6a4538d39efd..c3beae5c1be7 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -669,18 +669,16 @@ void blk_rq_set_mixed_merge(struct request *rq) rq->rq_flags |= RQF_MIXED_MERGE; } -static void blk_account_io_merge(struct request *req) +static void blk_account_io_merge_request(struct request *req) { if (blk_do_io_stat(req)) { - struct hd_struct *part; - part_stat_lock(); - part = req->part; - - hd_struct_put(part); + part_stat_inc(req->part, merges[op_stat_group(req_op(req))]); + hd_struct_put(req->part); part_stat_unlock(); } } + /* * Two cases of handling DISCARD merge: * If max_discard_segments > 1, the driver takes every bio @@ -792,7 +790,7 @@ static struct request *attempt_merge(struct request_queue *q, /* * 'next' is going away, so update stats accordingly */ - blk_account_io_merge(next); + blk_account_io_merge_request(next); /* * ownership of bio passed from next to req, return 'next' for -- cgit v1.2.3 From b5af37ab3a2b143e278340d2c6fa5790d53817e7 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Wed, 27 May 2020 07:24:16 +0200 Subject: block: add a blk_account_io_merge_bio helper Move the non-"new_io" branch of blk_account_io_start() into separate function. Fix merge accounting for discards (they were counted as write merges). The new blk_account_io_merge_bio() doesn't call update_io_ticks() unlike blk_account_io_start(), as there is no reason for that. [hch: rebased] Signed-off-by: Konstantin Khlebnikov Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/blk-core.c | 25 ++++++++++++++++--------- block/blk-exec.c | 2 +- block/blk-mq.c | 2 +- block/blk.h | 2 +- 4 files changed, 19 insertions(+), 12 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index c1675d43c2da..bf2f7d4bc0c1 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -636,6 +636,16 @@ void blk_put_request(struct request *req) } EXPORT_SYMBOL(blk_put_request); +static void blk_account_io_merge_bio(struct request *req) +{ + if (!blk_do_io_stat(req)) + return; + + part_stat_lock(); + part_stat_inc(req->part, merges[op_stat_group(req_op(req))]); + part_stat_unlock(); +} + bool bio_attempt_back_merge(struct request *req, struct bio *bio, unsigned int nr_segs) { @@ -656,7 +666,7 @@ bool bio_attempt_back_merge(struct request *req, struct bio *bio, bio_crypt_free_ctx(bio); - blk_account_io_start(req, false); + blk_account_io_merge_bio(req); return true; } @@ -682,7 +692,7 @@ bool bio_attempt_front_merge(struct request *req, struct bio *bio, bio_crypt_do_front_merge(req, bio); - blk_account_io_start(req, false); + blk_account_io_merge_bio(req); return true; } @@ -704,7 +714,7 @@ bool bio_attempt_discard_merge(struct request_queue *q, struct request *req, req->__data_len += bio->bi_iter.bi_size; req->nr_phys_segments = segments + 1; - blk_account_io_start(req, false); + blk_account_io_merge_bio(req); return true; no_merge: req_set_nomerge(q, req); @@ -1329,7 +1339,7 @@ blk_status_t blk_insert_cloned_request(struct request_queue *q, struct request * return BLK_STS_IOERR; if (blk_queue_io_stat(q)) - blk_account_io_start(rq, true); + blk_account_io_start(rq); /* * Since we have a scheduler attached on the top device, @@ -1433,16 +1443,13 @@ void blk_account_io_done(struct request *req, u64 now) } } -void blk_account_io_start(struct request *rq, bool new_io) +void blk_account_io_start(struct request *rq) { if (!blk_do_io_stat(rq)) return; part_stat_lock(); - if (!new_io) - part_stat_inc(rq->part, merges[rq_data_dir(rq)]); - else - rq->part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); + rq->part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); update_io_ticks(rq->part, jiffies, false); part_stat_unlock(); } diff --git a/block/blk-exec.c b/block/blk-exec.c index e20a852ae432..85324d53d072 100644 --- a/block/blk-exec.c +++ b/block/blk-exec.c @@ -55,7 +55,7 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk, rq->rq_disk = bd_disk; rq->end_io = done; - blk_account_io_start(rq, true); + blk_account_io_start(rq); /* * don't check dying flag for MQ because the request won't diff --git a/block/blk-mq.c b/block/blk-mq.c index cac11945f602..c606c74463cc 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -1822,7 +1822,7 @@ static void blk_mq_bio_to_request(struct request *rq, struct bio *bio, blk_rq_bio_prep(rq, bio, nr_segs); blk_crypto_rq_bio_prep(rq, bio, GFP_NOIO); - blk_account_io_start(rq, true); + blk_account_io_start(rq); } static blk_status_t __blk_mq_issue_directly(struct blk_mq_hw_ctx *hctx, diff --git a/block/blk.h b/block/blk.h index 0ecba2ab383d..428f7e5d70a8 100644 --- a/block/blk.h +++ b/block/blk.h @@ -185,7 +185,7 @@ bool bio_attempt_discard_merge(struct request_queue *q, struct request *req, bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, unsigned int nr_segs, struct request **same_queue_rq); -void blk_account_io_start(struct request *req, bool new_io); +void blk_account_io_start(struct request *req); void blk_account_io_done(struct request *req, u64 now); /* -- cgit v1.2.3 From 8ab1d40a646e753adb6814642432a093d93dbf47 Mon Sep 17 00:00:00 2001 From: Konstantin Khlebnikov Date: Wed, 27 May 2020 07:24:17 +0200 Subject: block: remove rcu_read_lock() from part_stat_lock() The RCU lock is required only in disk_map_sector_rcu() to lookup the partition. After that request holds reference to related hd_struct. Replace get_cpu() with preempt_disable() - returned cpu index is unused. [hch: rebased] Signed-off-by: Konstantin Khlebnikov Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe --- block/genhd.c | 11 ++++++++--- include/linux/part_stat.h | 4 ++-- 2 files changed, 10 insertions(+), 5 deletions(-) (limited to 'block') diff --git a/block/genhd.c b/block/genhd.c index 3e7df0a3e6bb..1a7659327664 100644 --- a/block/genhd.c +++ b/block/genhd.c @@ -321,11 +321,12 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) struct hd_struct *part; int i; + rcu_read_lock(); ptbl = rcu_dereference(disk->part_tbl); part = rcu_dereference(ptbl->last_lookup); if (part && sector_in_part(part, sector) && hd_struct_try_get(part)) - return part; + goto out_unlock; for (i = 1; i < ptbl->len; i++) { part = rcu_dereference(ptbl->part[i]); @@ -339,10 +340,14 @@ struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector) if (!hd_struct_try_get(part)) break; rcu_assign_pointer(ptbl->last_lookup, part); - return part; + goto out_unlock; } } - return &disk->part0; + + part = &disk->part0; +out_unlock: + rcu_read_unlock(); + return part; } /** diff --git a/include/linux/part_stat.h b/include/linux/part_stat.h index 6644197980b9..a6b0938ce82e 100644 --- a/include/linux/part_stat.h +++ b/include/linux/part_stat.h @@ -21,8 +21,8 @@ struct disk_stats { * * part_stat_read() can be called at any time. */ -#define part_stat_lock() ({ rcu_read_lock(); get_cpu(); }) -#define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0) +#define part_stat_lock() preempt_disable() +#define part_stat_unlock() preempt_enable() #define part_stat_get_cpu(part, field, cpu) \ (per_cpu_ptr((part)->dkstats, (cpu))->field) -- cgit v1.2.3 From 524f9ffd6a4d3622aa48ca286ff85a30ed1cdbcf Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 27 May 2020 07:24:19 +0200 Subject: block: reduce part_stat_lock() scope We only need the stats lock (aka preempt_disable()) for updating the states, not for looking up or dropping the hd_struct reference. Signed-off-by: Christoph Hellwig Reviewed-by: Konstantin Khlebnikov Signed-off-by: Jens Axboe --- block/blk-core.c | 5 +++-- block/blk-merge.c | 3 ++- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'block') diff --git a/block/blk-core.c b/block/blk-core.c index bf2f7d4bc0c1..a01fb2b508f0 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1437,9 +1437,9 @@ void blk_account_io_done(struct request *req, u64 now) update_io_ticks(part, jiffies, true); part_stat_inc(part, ios[sgrp]); part_stat_add(part, nsecs[sgrp], now - req->start_time_ns); + part_stat_unlock(); hd_struct_put(part); - part_stat_unlock(); } } @@ -1448,8 +1448,9 @@ void blk_account_io_start(struct request *rq) if (!blk_do_io_stat(rq)) return; - part_stat_lock(); rq->part = disk_map_sector_rcu(rq->rq_disk, blk_rq_pos(rq)); + + part_stat_lock(); update_io_ticks(rq->part, jiffies, false); part_stat_unlock(); } diff --git a/block/blk-merge.c b/block/blk-merge.c index c3beae5c1be7..f0b0bae075a0 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -674,8 +674,9 @@ static void blk_account_io_merge_request(struct request *req) if (blk_do_io_stat(req)) { part_stat_lock(); part_stat_inc(req->part, merges[op_stat_group(req_op(req))]); - hd_struct_put(req->part); part_stat_unlock(); + + hd_struct_put(req->part); } } -- cgit v1.2.3 From e7ecc142e9f33f5a8808b13fb0afa14f36aeeca3 Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Tue, 26 May 2020 23:49:02 +0100 Subject: block: blk-crypto-fallback: remove redundant initialization of variable err The variable err is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Signed-off-by: Colin Ian King Reviewed-by: Eric Biggers Reviewed-by: Satya Tangirala Addresses-Coverity: ("Unused value") Signed-off-by: Jens Axboe --- block/blk-crypto-fallback.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'block') diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c index 74ab137ae3ba..6e49688a2d80 100644 --- a/block/blk-crypto-fallback.c +++ b/block/blk-crypto-fallback.c @@ -529,7 +529,7 @@ static bool blk_crypto_fallback_inited; static int blk_crypto_fallback_init(void) { int i; - int err = -ENOMEM; + int err; if (blk_crypto_fallback_inited) return 0; -- cgit v1.2.3 From 7b11eab041dacfeaaa6d27d9183b247a995bc16d Mon Sep 17 00:00:00 2001 From: Keith Busch Date: Fri, 29 May 2020 07:51:59 -0700 Subject: blk-mq: blk-mq: provide forced completion method Drivers may need to bypass error injection for error recovery. Rename __blk_mq_complete_request() to blk_mq_force_complete_rq() and export that function so drivers may skip potential fake timeouts after they've reclaimed lost requests. Signed-off-by: Keith Busch Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/blk-mq.c | 15 +++++++++++++-- include/linux/blk-mq.h | 1 + 2 files changed, 14 insertions(+), 2 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index c606c74463cc..c6dcd390be2d 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -556,7 +556,17 @@ static void __blk_mq_complete_request_remote(void *data) q->mq_ops->complete(rq); } -static void __blk_mq_complete_request(struct request *rq) +/** + * blk_mq_force_complete_rq() - Force complete the request, bypassing any error + * injection that could drop the completion. + * @rq: Request to be force completed + * + * Drivers should use blk_mq_complete_request() to complete requests in their + * normal IO path. For timeout error recovery, drivers may call this forced + * completion routine after they've reclaimed timed out requests to bypass + * potentially subsequent fake timeouts. + */ +void blk_mq_force_complete_rq(struct request *rq) { struct blk_mq_ctx *ctx = rq->mq_ctx; struct request_queue *q = rq->q; @@ -602,6 +612,7 @@ static void __blk_mq_complete_request(struct request *rq) } put_cpu(); } +EXPORT_SYMBOL_GPL(blk_mq_force_complete_rq); static void hctx_unlock(struct blk_mq_hw_ctx *hctx, int srcu_idx) __releases(hctx->srcu) @@ -635,7 +646,7 @@ bool blk_mq_complete_request(struct request *rq) { if (unlikely(blk_should_fake_timeout(rq->q))) return false; - __blk_mq_complete_request(rq); + blk_mq_force_complete_rq(rq); return true; } EXPORT_SYMBOL(blk_mq_complete_request); diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index d7307795439a..856bb10993cf 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -494,6 +494,7 @@ void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list); void blk_mq_kick_requeue_list(struct request_queue *q); void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs); bool blk_mq_complete_request(struct request *rq); +void blk_mq_force_complete_rq(struct request *rq); bool blk_mq_bio_list_merge(struct request_queue *q, struct list_head *list, struct bio *bio, unsigned int nr_segs); bool blk_mq_queue_stopped(struct request_queue *q); -- cgit v1.2.3 From 5d9c305b8ea3fbc95bedfde01f7dd91e68082098 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 May 2020 15:53:08 +0200 Subject: blk-mq: remove the bio argument to ->prepare_request None of the I/O schedulers actually needs it. Signed-off-by: Christoph Hellwig Reviewed-by: Ming Lei Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Bart Van Assche Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/bfq-iosched.c | 2 +- block/blk-mq.c | 2 +- block/kyber-iosched.c | 2 +- block/mq-deadline.c | 2 +- include/linux/elevator.h | 2 +- 5 files changed, 5 insertions(+), 5 deletions(-) (limited to 'block') diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c index 3d411716d7ee..50c8f034c01c 100644 --- a/block/bfq-iosched.c +++ b/block/bfq-iosched.c @@ -6073,7 +6073,7 @@ static struct bfq_queue *bfq_get_bfqq_handle_split(struct bfq_data *bfqd, * comments on bfq_init_rq for the reason behind this delayed * preparation. */ -static void bfq_prepare_request(struct request *rq, struct bio *bio) +static void bfq_prepare_request(struct request *rq) { /* * Regardless of whether we have an icq attached, we have to diff --git a/block/blk-mq.c b/block/blk-mq.c index c6dcd390be2d..f15722cbfac6 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -387,7 +387,7 @@ static struct request *blk_mq_get_request(struct request_queue *q, if (e->type->icq_cache) blk_mq_sched_assign_ioc(rq); - e->type->ops.prepare_request(rq, bio); + e->type->ops.prepare_request(rq); rq->rq_flags |= RQF_ELVPRIV; } } diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c index 34dcea0ef637..a38c5ab103d1 100644 --- a/block/kyber-iosched.c +++ b/block/kyber-iosched.c @@ -579,7 +579,7 @@ static bool kyber_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio, return merged; } -static void kyber_prepare_request(struct request *rq, struct bio *bio) +static void kyber_prepare_request(struct request *rq) { rq_set_domain_token(rq, -1); } diff --git a/block/mq-deadline.c b/block/mq-deadline.c index b490f47fd553..b57470e154c8 100644 --- a/block/mq-deadline.c +++ b/block/mq-deadline.c @@ -541,7 +541,7 @@ static void dd_insert_requests(struct blk_mq_hw_ctx *hctx, * Nothing to do here. This is defined only to ensure that .finish_request * method is called upon request completion. */ -static void dd_prepare_request(struct request *rq, struct bio *bio) +static void dd_prepare_request(struct request *rq) { } diff --git a/include/linux/elevator.h b/include/linux/elevator.h index 901bda352dcb..bacc40a0bdf3 100644 --- a/include/linux/elevator.h +++ b/include/linux/elevator.h @@ -39,7 +39,7 @@ struct elevator_mq_ops { void (*request_merged)(struct request_queue *, struct request *, enum elv_merge); void (*requests_merged)(struct request_queue *, struct request *, struct request *); void (*limit_depth)(unsigned int, struct blk_mq_alloc_data *); - void (*prepare_request)(struct request *, struct bio *bio); + void (*prepare_request)(struct request *); void (*finish_request)(struct request *); void (*insert_requests)(struct blk_mq_hw_ctx *, struct list_head *, bool); struct request *(*dispatch_request)(struct blk_mq_hw_ctx *); -- cgit v1.2.3 From e6e7abffe386b614a194ec32457a00c304c980f4 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 May 2020 15:53:09 +0200 Subject: blk-mq: simplify the blk_mq_get_request calling convention The bio argument is entirely unused, and the request_queue can be passed through the alloc_data, given that it needs to be filled out for the low-level tag allocation anyway. Also rename the function to __blk_mq_alloc_request as the switch between get and alloc in the call chains is rather confusing. Signed-off-by: Christoph Hellwig Reviewed-by: Ming Lei Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Bart Van Assche Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/blk-mq.c | 36 ++++++++++++++++++++++-------------- 1 file changed, 22 insertions(+), 14 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index f15722cbfac6..74ebab41f7d2 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -332,10 +332,9 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, return rq; } -static struct request *blk_mq_get_request(struct request_queue *q, - struct bio *bio, - struct blk_mq_alloc_data *data) +static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) { + struct request_queue *q = data->q; struct elevator_queue *e = q->elevator; struct request *rq; unsigned int tag; @@ -346,7 +345,6 @@ static struct request *blk_mq_get_request(struct request_queue *q, if (blk_queue_rq_alloc_time(q)) alloc_time_ns = ktime_get_ns(); - data->q = q; if (likely(!data->ctx)) { data->ctx = blk_mq_get_ctx(q); clear_ctx_on_error = true; @@ -398,7 +396,11 @@ static struct request *blk_mq_get_request(struct request_queue *q, struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, blk_mq_req_flags_t flags) { - struct blk_mq_alloc_data alloc_data = { .flags = flags, .cmd_flags = op }; + struct blk_mq_alloc_data data = { + .q = q, + .flags = flags, + .cmd_flags = op, + }; struct request *rq; int ret; @@ -406,7 +408,7 @@ struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, if (ret) return ERR_PTR(ret); - rq = blk_mq_get_request(q, NULL, &alloc_data); + rq = __blk_mq_alloc_request(&data); if (!rq) goto out_queue_exit; rq->__data_len = 0; @@ -422,7 +424,11 @@ EXPORT_SYMBOL(blk_mq_alloc_request); struct request *blk_mq_alloc_request_hctx(struct request_queue *q, unsigned int op, blk_mq_req_flags_t flags, unsigned int hctx_idx) { - struct blk_mq_alloc_data alloc_data = { .flags = flags, .cmd_flags = op }; + struct blk_mq_alloc_data data = { + .q = q, + .flags = flags, + .cmd_flags = op, + }; struct request *rq; unsigned int cpu; int ret; @@ -448,14 +454,14 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, * If not tell the caller that it should skip this queue. */ ret = -EXDEV; - alloc_data.hctx = q->queue_hw_ctx[hctx_idx]; - if (!blk_mq_hw_queue_mapped(alloc_data.hctx)) + data.hctx = q->queue_hw_ctx[hctx_idx]; + if (!blk_mq_hw_queue_mapped(data.hctx)) goto out_queue_exit; - cpu = cpumask_first_and(alloc_data.hctx->cpumask, cpu_online_mask); - alloc_data.ctx = __blk_mq_get_ctx(q, cpu); + cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask); + data.ctx = __blk_mq_get_ctx(q, cpu); ret = -EWOULDBLOCK; - rq = blk_mq_get_request(q, NULL, &alloc_data); + rq = __blk_mq_alloc_request(&data); if (!rq) goto out_queue_exit; return rq; @@ -2027,7 +2033,9 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) { const int is_sync = op_is_sync(bio->bi_opf); const int is_flush_fua = op_is_flush(bio->bi_opf); - struct blk_mq_alloc_data data = { .flags = 0}; + struct blk_mq_alloc_data data = { + .q = q, + }; struct request *rq; struct blk_plug *plug; struct request *same_queue_rq = NULL; @@ -2051,7 +2059,7 @@ blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) rq_qos_throttle(q, bio); data.cmd_flags = bio->bi_opf; - rq = blk_mq_get_request(q, bio, &data); + rq = __blk_mq_alloc_request(&data); if (unlikely(!rq)) { rq_qos_cleanup(q, bio); if (bio->bi_opf & REQ_NOWAIT) -- cgit v1.2.3 From 7ea4d8a4d683298abd346abf89567774de2fa34a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 May 2020 15:53:10 +0200 Subject: blk-mq: move more request initialization to blk_mq_rq_ctx_init Don't split request initialization between __blk_mq_alloc_request and blk_mq_rq_ctx_init. Also remove the op argument as it can be derived from the blk_mq_alloc_data structure. Signed-off-by: Christoph Hellwig Reviewed-by: Ming Lei Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Bart Van Assche Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/blk-mq.c | 36 +++++++++++++++++++----------------- 1 file changed, 19 insertions(+), 17 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index 74ebab41f7d2..b20ad88d2d70 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -271,7 +271,7 @@ static inline bool blk_mq_need_time_stamp(struct request *rq) } static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, - unsigned int tag, unsigned int op, u64 alloc_time_ns) + unsigned int tag, u64 alloc_time_ns) { struct blk_mq_tags *tags = blk_mq_tags_from_data(data); struct request *rq = tags->static_rqs[tag]; @@ -295,7 +295,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, rq->mq_ctx = data->ctx; rq->mq_hctx = data->hctx; rq->rq_flags = rq_flags; - rq->cmd_flags = op; + rq->cmd_flags = data->cmd_flags; if (data->flags & BLK_MQ_REQ_PREEMPT) rq->rq_flags |= RQF_PREEMPT; if (blk_queue_io_stat(data->q)) @@ -327,8 +327,23 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, rq->end_io = NULL; rq->end_io_data = NULL; - data->ctx->rq_dispatched[op_is_sync(op)]++; + data->ctx->rq_dispatched[op_is_sync(data->cmd_flags)]++; refcount_set(&rq->ref, 1); + + if (!op_is_flush(data->cmd_flags)) { + struct elevator_queue *e = data->q->elevator; + + rq->elv.icq = NULL; + if (e && e->type->ops.prepare_request) { + if (e->type->icq_cache) + blk_mq_sched_assign_ioc(rq); + + e->type->ops.prepare_request(rq); + rq->rq_flags |= RQF_ELVPRIV; + } + } + + data->hctx->queued++; return rq; } @@ -336,7 +351,6 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) { struct request_queue *q = data->q; struct elevator_queue *e = q->elevator; - struct request *rq; unsigned int tag; bool clear_ctx_on_error = false; u64 alloc_time_ns = 0; @@ -378,19 +392,7 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) return NULL; } - rq = blk_mq_rq_ctx_init(data, tag, data->cmd_flags, alloc_time_ns); - if (!op_is_flush(data->cmd_flags)) { - rq->elv.icq = NULL; - if (e && e->type->ops.prepare_request) { - if (e->type->icq_cache) - blk_mq_sched_assign_ioc(rq); - - e->type->ops.prepare_request(rq); - rq->rq_flags |= RQF_ELVPRIV; - } - } - data->hctx->queued++; - return rq; + return blk_mq_rq_ctx_init(data, tag, alloc_time_ns); } struct request *blk_mq_alloc_request(struct request_queue *q, unsigned int op, -- cgit v1.2.3 From 419c3d5e8012928fbf9a086b07b618146cc9277b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 May 2020 15:53:11 +0200 Subject: blk-mq: rename BLK_MQ_TAG_FAIL to BLK_MQ_NO_TAG To prepare for wider use of this constant give it a more applicable name. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Bart Van Assche Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 4 ++-- block/blk-mq-tag.h | 4 ++-- block/blk-mq.c | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-) (limited to 'block') diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 586c9d6e904a..c76ba4f90fa0 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -111,7 +111,7 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) if (data->flags & BLK_MQ_REQ_RESERVED) { if (unlikely(!tags->nr_reserved_tags)) { WARN_ON_ONCE(1); - return BLK_MQ_TAG_FAIL; + return BLK_MQ_NO_TAG; } bt = &tags->breserved_tags; tag_offset = 0; @@ -125,7 +125,7 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) goto found_tag; if (data->flags & BLK_MQ_REQ_NOWAIT) - return BLK_MQ_TAG_FAIL; + return BLK_MQ_NO_TAG; ws = bt_wait_ptr(bt, data->hctx); do { diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index 2b8321efb682..8a741752af8b 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -44,9 +44,9 @@ static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt, } enum { - BLK_MQ_TAG_FAIL = -1U, + BLK_MQ_NO_TAG = -1U, BLK_MQ_TAG_MIN = 1, - BLK_MQ_TAG_MAX = BLK_MQ_TAG_FAIL - 1, + BLK_MQ_TAG_MAX = BLK_MQ_NO_TAG - 1, }; extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *); diff --git a/block/blk-mq.c b/block/blk-mq.c index b20ad88d2d70..cd2fd7f8524c 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -386,7 +386,7 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) } tag = blk_mq_get_tag(data); - if (tag == BLK_MQ_TAG_FAIL) { + if (tag == BLK_MQ_NO_TAG) { if (clear_ctx_on_error) data->ctx = NULL; return NULL; -- cgit v1.2.3 From 766473681c131f2da81d62472864c8c97e021373 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 May 2020 15:53:12 +0200 Subject: blk-mq: use BLK_MQ_NO_TAG in more places Replace various magic -1 constants for tags with BLK_MQ_NO_TAG. Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Reviewed-by: Bart Van Assche Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 8 ++++---- block/blk-mq.c | 14 +++++++------- block/blk-mq.h | 4 ++-- 3 files changed, 13 insertions(+), 13 deletions(-) (limited to 'block') diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index c76ba4f90fa0..597ff9c27cf6 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -92,7 +92,7 @@ static int __blk_mq_get_tag(struct blk_mq_alloc_data *data, { if (!(data->flags & BLK_MQ_REQ_INTERNAL) && !hctx_may_queue(data->hctx, bt)) - return -1; + return BLK_MQ_NO_TAG; if (data->shallow_depth) return __sbitmap_queue_get_shallow(bt, data->shallow_depth); else @@ -121,7 +121,7 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) } tag = __blk_mq_get_tag(data, bt); - if (tag != -1) + if (tag != BLK_MQ_NO_TAG) goto found_tag; if (data->flags & BLK_MQ_REQ_NOWAIT) @@ -143,13 +143,13 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) * as running the queue may also have found completions. */ tag = __blk_mq_get_tag(data, bt); - if (tag != -1) + if (tag != BLK_MQ_NO_TAG) break; sbitmap_prepare_to_wait(bt, ws, &wait, TASK_UNINTERRUPTIBLE); tag = __blk_mq_get_tag(data, bt); - if (tag != -1) + if (tag != BLK_MQ_NO_TAG) break; bt_prev = bt; diff --git a/block/blk-mq.c b/block/blk-mq.c index cd2fd7f8524c..dcc52859a92c 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -278,7 +278,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, req_flags_t rq_flags = 0; if (data->flags & BLK_MQ_REQ_INTERNAL) { - rq->tag = -1; + rq->tag = BLK_MQ_NO_TAG; rq->internal_tag = tag; } else { if (data->hctx->flags & BLK_MQ_F_TAG_SHARED) { @@ -286,7 +286,7 @@ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, atomic_inc(&data->hctx->nr_active); } rq->tag = tag; - rq->internal_tag = -1; + rq->internal_tag = BLK_MQ_NO_TAG; data->hctx->tags->rqs[rq->tag] = rq; } @@ -483,9 +483,9 @@ static void __blk_mq_free_request(struct request *rq) blk_crypto_free_request(rq); blk_pm_mark_last_busy(rq); rq->mq_hctx = NULL; - if (rq->tag != -1) + if (rq->tag != BLK_MQ_NO_TAG) blk_mq_put_tag(hctx->tags, ctx, rq->tag); - if (sched_tag != -1) + if (sched_tag != BLK_MQ_NO_TAG) blk_mq_put_tag(hctx->sched_tags, ctx, sched_tag); blk_mq_sched_restart(hctx); blk_queue_exit(q); @@ -534,7 +534,7 @@ inline void __blk_mq_end_request(struct request *rq, blk_status_t error) blk_stat_add(rq, now); } - if (rq->internal_tag != -1) + if (rq->internal_tag != BLK_MQ_NO_TAG) blk_mq_sched_completed_request(rq, now); blk_account_io_done(rq, now); @@ -1044,7 +1044,7 @@ bool blk_mq_get_driver_tag(struct request *rq) }; bool shared; - if (rq->tag != -1) + if (rq->tag != BLK_MQ_NO_TAG) return true; if (blk_mq_tag_is_reserved(data.hctx->sched_tags, rq->internal_tag)) @@ -1060,7 +1060,7 @@ bool blk_mq_get_driver_tag(struct request *rq) data.hctx->tags->rqs[rq->tag] = rq; } - return rq->tag != -1; + return rq->tag != BLK_MQ_NO_TAG; } static int blk_mq_dispatch_wake(wait_queue_entry_t *wait, unsigned mode, diff --git a/block/blk-mq.h b/block/blk-mq.h index 10bfdfb494fa..a139b0631817 100644 --- a/block/blk-mq.h +++ b/block/blk-mq.h @@ -201,7 +201,7 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, struct request *rq) { blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag); - rq->tag = -1; + rq->tag = BLK_MQ_NO_TAG; if (rq->rq_flags & RQF_MQ_INFLIGHT) { rq->rq_flags &= ~RQF_MQ_INFLIGHT; @@ -211,7 +211,7 @@ static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, static inline void blk_mq_put_driver_tag(struct request *rq) { - if (rq->tag == -1 || rq->internal_tag == -1) + if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG) return; __blk_mq_put_driver_tag(rq->mq_hctx, rq); -- cgit v1.2.3 From 600c3b0cea784aaba77df3ed4a6b4f2ebfa935ce Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 29 May 2020 15:53:13 +0200 Subject: blk-mq: open code __blk_mq_alloc_request in blk_mq_alloc_request_hctx blk_mq_alloc_request_hctx is only used for NVMeoF connect commands, so tailor it to the specific requirements, and don't bother the general fast path code with its special twinkles. Signed-off-by: Christoph Hellwig Reviewed-by: Ming Lei Reviewed-by: Hannes Reinecke Signed-off-by: Jens Axboe --- block/blk-mq.c | 44 +++++++++++++++++++++++--------------------- 1 file changed, 23 insertions(+), 21 deletions(-) (limited to 'block') diff --git a/block/blk-mq.c b/block/blk-mq.c index dcc52859a92c..560ef5df8993 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -351,21 +351,13 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) { struct request_queue *q = data->q; struct elevator_queue *e = q->elevator; - unsigned int tag; - bool clear_ctx_on_error = false; u64 alloc_time_ns = 0; + unsigned int tag; /* alloc_time includes depth and tag waits */ if (blk_queue_rq_alloc_time(q)) alloc_time_ns = ktime_get_ns(); - if (likely(!data->ctx)) { - data->ctx = blk_mq_get_ctx(q); - clear_ctx_on_error = true; - } - if (likely(!data->hctx)) - data->hctx = blk_mq_map_queue(q, data->cmd_flags, - data->ctx); if (data->cmd_flags & REQ_NOWAIT) data->flags |= BLK_MQ_REQ_NOWAIT; @@ -381,17 +373,16 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) e->type->ops.limit_depth && !(data->flags & BLK_MQ_REQ_RESERVED)) e->type->ops.limit_depth(data->cmd_flags, data); - } else { - blk_mq_tag_busy(data->hctx); } + data->ctx = blk_mq_get_ctx(q); + data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); + if (!(data->flags & BLK_MQ_REQ_INTERNAL)) + blk_mq_tag_busy(data->hctx); + tag = blk_mq_get_tag(data); - if (tag == BLK_MQ_NO_TAG) { - if (clear_ctx_on_error) - data->ctx = NULL; + if (tag == BLK_MQ_NO_TAG) return NULL; - } - return blk_mq_rq_ctx_init(data, tag, alloc_time_ns); } @@ -431,17 +422,22 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, .flags = flags, .cmd_flags = op, }; - struct request *rq; + u64 alloc_time_ns = 0; unsigned int cpu; + unsigned int tag; int ret; + /* alloc_time includes depth and tag waits */ + if (blk_queue_rq_alloc_time(q)) + alloc_time_ns = ktime_get_ns(); + /* * If the tag allocator sleeps we could get an allocation for a * different hardware context. No need to complicate the low level * allocator for this for the rare use case of a command tied to * a specific queue. */ - if (WARN_ON_ONCE(!(flags & BLK_MQ_REQ_NOWAIT))) + if (WARN_ON_ONCE(!(flags & (BLK_MQ_REQ_NOWAIT | BLK_MQ_REQ_RESERVED)))) return ERR_PTR(-EINVAL); if (hctx_idx >= q->nr_hw_queues) @@ -462,11 +458,17 @@ struct request *blk_mq_alloc_request_hctx(struct request_queue *q, cpu = cpumask_first_and(data.hctx->cpumask, cpu_online_mask); data.ctx = __blk_mq_get_ctx(q, cpu); + if (q->elevator) + data.flags |= BLK_MQ_REQ_INTERNAL; + else + blk_mq_tag_busy(data.hctx); + ret = -EWOULDBLOCK; - rq = __blk_mq_alloc_request(&data); - if (!rq) + tag = blk_mq_get_tag(&data); + if (tag == BLK_MQ_NO_TAG) goto out_queue_exit; - return rq; + return blk_mq_rq_ctx_init(&data, tag, alloc_time_ns); + out_queue_exit: blk_queue_exit(q); return ERR_PTR(ret); -- cgit v1.2.3 From 602380d28e28b454683efac41dc4b2862d055d91 Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 29 May 2020 15:53:14 +0200 Subject: blk-mq: add blk_mq_all_tag_iter Add a new blk_mq_all_tag_iter function to iterate over all allocated scheduler tags and driver tags. This is more flexible than the existing blk_mq_all_tag_busy_iter function as it allows the callers to do whatever they want on allocated request instead of being limited to started requests. It will be used to implement draining allocated requests on specified hctx in this patchset. [hch: switch from the two booleans to a more readable flags field and consolidate the tags iter functions] Signed-off-by: Ming Lei Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Daniel Wagner Reviewed-by: Bart van Assche Signed-off-by: Jens Axboe --- block/blk-mq-tag.c | 50 ++++++++++++++++++++++++++++++++------------------ block/blk-mq-tag.h | 2 ++ 2 files changed, 34 insertions(+), 18 deletions(-) (limited to 'block') diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 597ff9c27cf6..762198b62088 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -256,14 +256,17 @@ struct bt_tags_iter_data { struct blk_mq_tags *tags; busy_tag_iter_fn *fn; void *data; - bool reserved; + unsigned int flags; }; +#define BT_TAG_ITER_RESERVED (1 << 0) +#define BT_TAG_ITER_STARTED (1 << 1) + static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) { struct bt_tags_iter_data *iter_data = data; struct blk_mq_tags *tags = iter_data->tags; - bool reserved = iter_data->reserved; + bool reserved = iter_data->flags & BT_TAG_ITER_RESERVED; struct request *rq; if (!reserved) @@ -274,10 +277,12 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) * test and set the bit before assining ->rqs[]. */ rq = tags->rqs[bitnr]; - if (rq && blk_mq_request_started(rq)) - return iter_data->fn(rq, iter_data->data, reserved); - - return true; + if (!rq) + return true; + if ((iter_data->flags & BT_TAG_ITER_STARTED) && + !blk_mq_request_started(rq)) + return true; + return iter_data->fn(rq, iter_data->data, reserved); } /** @@ -290,39 +295,47 @@ static bool bt_tags_iter(struct sbitmap *bitmap, unsigned int bitnr, void *data) * @reserved) where rq is a pointer to a request. Return true * to continue iterating tags, false to stop. * @data: Will be passed as second argument to @fn. - * @reserved: Indicates whether @bt is the breserved_tags member or the - * bitmap_tags member of struct blk_mq_tags. + * @flags: BT_TAG_ITER_* */ static void bt_tags_for_each(struct blk_mq_tags *tags, struct sbitmap_queue *bt, - busy_tag_iter_fn *fn, void *data, bool reserved) + busy_tag_iter_fn *fn, void *data, unsigned int flags) { struct bt_tags_iter_data iter_data = { .tags = tags, .fn = fn, .data = data, - .reserved = reserved, + .flags = flags, }; if (tags->rqs) sbitmap_for_each_set(&bt->sb, bt_tags_iter, &iter_data); } +static void __blk_mq_all_tag_iter(struct blk_mq_tags *tags, + busy_tag_iter_fn *fn, void *priv, unsigned int flags) +{ + WARN_ON_ONCE(flags & BT_TAG_ITER_RESERVED); + + if (tags->nr_reserved_tags) + bt_tags_for_each(tags, &tags->breserved_tags, fn, priv, + flags | BT_TAG_ITER_RESERVED); + bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, flags); +} + /** - * blk_mq_all_tag_busy_iter - iterate over all started requests in a tag map + * blk_mq_all_tag_iter - iterate over all requests in a tag map * @tags: Tag map to iterate over. - * @fn: Pointer to the function that will be called for each started + * @fn: Pointer to the function that will be called for each * request. @fn will be called as follows: @fn(rq, @priv, * reserved) where rq is a pointer to a request. 'reserved' * indicates whether or not @rq is a reserved request. Return * true to continue iterating tags, false to stop. * @priv: Will be passed as second argument to @fn. */ -static void blk_mq_all_tag_busy_iter(struct blk_mq_tags *tags, - busy_tag_iter_fn *fn, void *priv) +void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn, + void *priv) { - if (tags->nr_reserved_tags) - bt_tags_for_each(tags, &tags->breserved_tags, fn, priv, true); - bt_tags_for_each(tags, &tags->bitmap_tags, fn, priv, false); + return __blk_mq_all_tag_iter(tags, fn, priv, 0); } /** @@ -342,7 +355,8 @@ void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, for (i = 0; i < tagset->nr_hw_queues; i++) { if (tagset->tags && tagset->tags[i]) - blk_mq_all_tag_busy_iter(tagset->tags[i], fn, priv); + __blk_mq_all_tag_iter(tagset->tags[i], fn, priv, + BT_TAG_ITER_STARTED); } } EXPORT_SYMBOL(blk_mq_tagset_busy_iter); diff --git a/block/blk-mq-tag.h b/block/blk-mq-tag.h index 8a741752af8b..d38e48f2a0a4 100644 --- a/block/blk-mq-tag.h +++ b/block/blk-mq-tag.h @@ -34,6 +34,8 @@ extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool); void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn, void *priv); +void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn, + void *priv); static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt, struct blk_mq_hw_ctx *hctx) -- cgit v1.2.3 From bf0beec0607db3c6f6fb7bd2c6d503792b05cf3f Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Fri, 29 May 2020 15:53:15 +0200 Subject: blk-mq: drain I/O when all CPUs in a hctx are offline Most of blk-mq drivers depend on managed IRQ's auto-affinity to setup up queue mapping. Thomas mentioned the following point[1]: "That was the constraint of managed interrupts from the very beginning: The driver/subsystem has to quiesce the interrupt line and the associated queue _before_ it gets shutdown in CPU unplug and not fiddle with it until it's restarted by the core when the CPU is plugged in again." However, current blk-mq implementation doesn't quiesce hw queue before the last CPU in the hctx is shutdown. Even worse, CPUHP_BLK_MQ_DEAD is a cpuhp state handled after the CPU is down, so there isn't any chance to quiesce the hctx before shutting down the CPU. Add new CPUHP_AP_BLK_MQ_ONLINE state to stop allocating from blk-mq hctxs where the last CPU goes away, and wait for completion of in-flight requests. This guarantees that there is no inflight I/O before shutting down the managed IRQ. Add a BLK_MQ_F_STACKING and set it for dm-rq and loop, so we don't need to wait for completion of in-flight requests from these drivers to avoid a potential dead-lock. It is safe to do this for stacking drivers as those do not use interrupts at all and their I/O completions are triggered by underlying devices I/O completion. [1] https://lore.kernel.org/linux-block/alpine.DEB.2.21.1904051331270.1802@nanos.tec.linutronix.de/ [hch: different retry mechanism, merged two patches, minor cleanups] Signed-off-by: Ming Lei Signed-off-by: Christoph Hellwig Reviewed-by: Hannes Reinecke Reviewed-by: Daniel Wagner Signed-off-by: Jens Axboe --- block/blk-mq-debugfs.c | 2 + block/blk-mq-tag.c | 8 ++++ block/blk-mq.c | 112 ++++++++++++++++++++++++++++++++++++++++++++- drivers/block/loop.c | 2 +- drivers/md/dm-rq.c | 2 +- include/linux/blk-mq.h | 10 ++++ include/linux/cpuhotplug.h | 1 + 7 files changed, 133 insertions(+), 4 deletions(-) (limited to 'block') diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index 96b7a35c898a..15df3a36e9fa 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -213,6 +213,7 @@ static const char *const hctx_state_name[] = { HCTX_STATE_NAME(STOPPED), HCTX_STATE_NAME(TAG_ACTIVE), HCTX_STATE_NAME(SCHED_RESTART), + HCTX_STATE_NAME(INACTIVE), }; #undef HCTX_STATE_NAME @@ -239,6 +240,7 @@ static const char *const hctx_flag_name[] = { HCTX_FLAG_NAME(TAG_SHARED), HCTX_FLAG_NAME(BLOCKING), HCTX_FLAG_NAME(NO_SCHED), + HCTX_FLAG_NAME(STACKING), }; #undef HCTX_FLAG_NAME diff --git a/block/blk-mq-tag.c b/block/blk-mq-tag.c index 762198b62088..96a39d0724a2 100644 --- a/block/blk-mq-tag.c +++ b/block/blk-mq-tag.c @@ -180,6 +180,14 @@ unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data) sbitmap_finish_wait(bt, ws, &wait); found_tag: + /* + * Give up this allocation if the hctx is inactive. The caller will + * retry on an active hctx. + */ + if (unlikely(test_bit(BLK_MQ_S_INACTIVE, &data->hctx->state))) { + blk_mq_put_tag(tags, data->ctx, tag + tag_offset); + return BLK_MQ_NO_TAG; + } return tag + tag_offset; } diff --git a/block/blk-mq.c b/block/blk-mq.c index 560ef5df8993..9a36ac1c1fa1 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -375,14 +375,30 @@ static struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data) e->type->ops.limit_depth(data->cmd_flags, data); } +retry: data->ctx = blk_mq_get_ctx(q); data->hctx = blk_mq_map_queue(q, data->cmd_flags, data->ctx); if (!(data->flags & BLK_MQ_REQ_INTERNAL)) blk_mq_tag_busy(data->hctx); + /* + * Waiting allocations only fail because of an inactive hctx. In that + * case just retry the hctx assignment and tag allocation as CPU hotplug + * should have migrated us to an online CPU by now. + */ tag = blk_mq_get_tag(data); - if (tag == BLK_MQ_NO_TAG) - return NULL; + if (tag == BLK_MQ_NO_TAG) { + if (data->flags & BLK_MQ_REQ_NOWAIT) + return NULL; + + /* + * Give up the CPU and sleep for a random short time to ensure + * that thread using a realtime scheduling class are migrated + * off the the CPU, and thus off the hctx that is going away. + */ + msleep(3); + goto retry; + } return blk_mq_rq_ctx_init(data, tag, alloc_time_ns); } @@ -2335,6 +2351,86 @@ fail: return -ENOMEM; } +struct rq_iter_data { + struct blk_mq_hw_ctx *hctx; + bool has_rq; +}; + +static bool blk_mq_has_request(struct request *rq, void *data, bool reserved) +{ + struct rq_iter_data *iter_data = data; + + if (rq->mq_hctx != iter_data->hctx) + return true; + iter_data->has_rq = true; + return false; +} + +static bool blk_mq_hctx_has_requests(struct blk_mq_hw_ctx *hctx) +{ + struct blk_mq_tags *tags = hctx->sched_tags ? + hctx->sched_tags : hctx->tags; + struct rq_iter_data data = { + .hctx = hctx, + }; + + blk_mq_all_tag_iter(tags, blk_mq_has_request, &data); + return data.has_rq; +} + +static inline bool blk_mq_last_cpu_in_hctx(unsigned int cpu, + struct blk_mq_hw_ctx *hctx) +{ + if (cpumask_next_and(-1, hctx->cpumask, cpu_online_mask) != cpu) + return false; + if (cpumask_next_and(cpu, hctx->cpumask, cpu_online_mask) < nr_cpu_ids) + return false; + return true; +} + +static int blk_mq_hctx_notify_offline(unsigned int cpu, struct hlist_node *node) +{ + struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node, + struct blk_mq_hw_ctx, cpuhp_online); + + if (!cpumask_test_cpu(cpu, hctx->cpumask) || + !blk_mq_last_cpu_in_hctx(cpu, hctx)) + return 0; + + /* + * Prevent new request from being allocated on the current hctx. + * + * The smp_mb__after_atomic() Pairs with the implied barrier in + * test_and_set_bit_lock in sbitmap_get(). Ensures the inactive flag is + * seen once we return from the tag allocator. + */ + set_bit(BLK_MQ_S_INACTIVE, &hctx->state); + smp_mb__after_atomic(); + + /* + * Try to grab a reference to the queue and wait for any outstanding + * requests. If we could not grab a reference the queue has been + * frozen and there are no requests. + */ + if (percpu_ref_tryget(&hctx->queue->q_usage_counter)) { + while (blk_mq_hctx_has_requests(hctx)) + msleep(5); + percpu_ref_put(&hctx->queue->q_usage_counter); + } + + return 0; +} + +static int blk_mq_hctx_notify_online(unsigned int cpu, struct hlist_node *node) +{ + struct blk_mq_hw_ctx *hctx = hlist_entry_safe(node, + struct blk_mq_hw_ctx, cpuhp_online); + + if (cpumask_test_cpu(cpu, hctx->cpumask)) + clear_bit(BLK_MQ_S_INACTIVE, &hctx->state); + return 0; +} + /* * 'cpu' is going away. splice any existing rq_list entries from this * software queue to the hw queue dispatch list, and ensure that it @@ -2348,6 +2444,9 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) enum hctx_type type; hctx = hlist_entry_safe(node, struct blk_mq_hw_ctx, cpuhp_dead); + if (!cpumask_test_cpu(cpu, hctx->cpumask)) + return 0; + ctx = __blk_mq_get_ctx(hctx->queue, cpu); type = hctx->type; @@ -2371,6 +2470,9 @@ static int blk_mq_hctx_notify_dead(unsigned int cpu, struct hlist_node *node) static void blk_mq_remove_cpuhp(struct blk_mq_hw_ctx *hctx) { + if (!(hctx->flags & BLK_MQ_F_STACKING)) + cpuhp_state_remove_instance_nocalls(CPUHP_AP_BLK_MQ_ONLINE, + &hctx->cpuhp_online); cpuhp_state_remove_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead); } @@ -2430,6 +2532,9 @@ static int blk_mq_init_hctx(struct request_queue *q, { hctx->queue_num = hctx_idx; + if (!(hctx->flags & BLK_MQ_F_STACKING)) + cpuhp_state_add_instance_nocalls(CPUHP_AP_BLK_MQ_ONLINE, + &hctx->cpuhp_online); cpuhp_state_add_instance_nocalls(CPUHP_BLK_MQ_DEAD, &hctx->cpuhp_dead); hctx->tags = set->tags[hctx_idx]; @@ -3684,6 +3789,9 @@ static int __init blk_mq_init(void) { cpuhp_setup_state_multi(CPUHP_BLK_MQ_DEAD, "block/mq:dead", NULL, blk_mq_hctx_notify_dead); + cpuhp_setup_state_multi(CPUHP_AP_BLK_MQ_ONLINE, "block/mq:online", + blk_mq_hctx_notify_online, + blk_mq_hctx_notify_offline); return 0; } subsys_initcall(blk_mq_init); diff --git a/drivers/block/loop.c b/drivers/block/loop.c index da693e6a834e..d7904b4d8d12 100644 --- a/drivers/block/loop.c +++ b/drivers/block/loop.c @@ -2037,7 +2037,7 @@ static int loop_add(struct loop_device **l, int i) lo->tag_set.queue_depth = 128; lo->tag_set.numa_node = NUMA_NO_NODE; lo->tag_set.cmd_size = sizeof(struct loop_cmd); - lo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE; + lo->tag_set.flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_STACKING; lo->tag_set.driver_data = lo; err = blk_mq_alloc_tag_set(&lo->tag_set); diff --git a/drivers/md/dm-rq.c b/drivers/md/dm-rq.c index 3f8577e2c13b..f60c02512121 100644 --- a/drivers/md/dm-rq.c +++ b/drivers/md/dm-rq.c @@ -547,7 +547,7 @@ int dm_mq_init_request_queue(struct mapped_device *md, struct dm_table *t) md->tag_set->ops = &dm_mq_ops; md->tag_set->queue_depth = dm_get_blk_mq_queue_depth(); md->tag_set->numa_node = md->numa_node_id; - md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE; + md->tag_set->flags = BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_STACKING; md->tag_set->nr_hw_queues = dm_get_blk_mq_nr_hw_queues(); md->tag_set->driver_data = md; diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h index 856bb10993cf..d6fcae17da5a 100644 --- a/include/linux/blk-mq.h +++ b/include/linux/blk-mq.h @@ -140,6 +140,8 @@ struct blk_mq_hw_ctx { */ atomic_t nr_active; + /** @cpuhp_online: List to store request if CPU is going to die */ + struct hlist_node cpuhp_online; /** @cpuhp_dead: List to store request if some CPU die. */ struct hlist_node cpuhp_dead; /** @kobj: Kernel object for sysfs. */ @@ -391,6 +393,11 @@ struct blk_mq_ops { enum { BLK_MQ_F_SHOULD_MERGE = 1 << 0, BLK_MQ_F_TAG_SHARED = 1 << 1, + /* + * Set when this device requires underlying blk-mq device for + * completing IO: + */ + BLK_MQ_F_STACKING = 1 << 2, BLK_MQ_F_BLOCKING = 1 << 5, BLK_MQ_F_NO_SCHED = 1 << 6, BLK_MQ_F_ALLOC_POLICY_START_BIT = 8, @@ -400,6 +407,9 @@ enum { BLK_MQ_S_TAG_ACTIVE = 1, BLK_MQ_S_SCHED_RESTART = 2, + /* hw queue is inactive after all its CPUs become offline */ + BLK_MQ_S_INACTIVE = 3, + BLK_MQ_MAX_DEPTH = 10240, BLK_MQ_CPU_WORK_BATCH = 8, diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 77d70b633531..24b3a77810b6 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -152,6 +152,7 @@ enum cpuhp_state { CPUHP_AP_SMPBOOT_THREADS, CPUHP_AP_X86_VDSO_VMA_ONLINE, CPUHP_AP_IRQ_AFFINITY_ONLINE, + CPUHP_AP_BLK_MQ_ONLINE, CPUHP_AP_ARM_MVEBU_SYNC_CLOCKS, CPUHP_AP_X86_INTEL_EPB_ONLINE, CPUHP_AP_PERF_ONLINE, -- cgit v1.2.3 From b77412372b6812a05eaa996e1a93cafa2fa1eec2 Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Sat, 9 May 2020 00:00:12 +0200 Subject: blk-throttle: remove blk_throtl_drain After the commit 5addeae1bedc4 ("blk-cgroup: remove blkcg_drain_queue"), there is no caller of blk_throtl_drain, so let's remove it. Signed-off-by: Guoqing Jiang Signed-off-by: Jens Axboe --- block/blk-throttle.c | 41 ----------------------------------------- block/blk.h | 2 -- 2 files changed, 43 deletions(-) (limited to 'block') diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 98233c9c65a8..0b2ce7fb77a7 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -2380,47 +2380,6 @@ static void tg_drain_bios(struct throtl_service_queue *parent_sq) } } -/** - * blk_throtl_drain - drain throttled bios - * @q: request_queue to drain throttled bios for - * - * Dispatch all currently throttled bios on @q through ->make_request_fn(). - */ -void blk_throtl_drain(struct request_queue *q) - __releases(&q->queue_lock) __acquires(&q->queue_lock) -{ - struct throtl_data *td = q->td; - struct blkcg_gq *blkg; - struct cgroup_subsys_state *pos_css; - struct bio *bio; - int rw; - - rcu_read_lock(); - - /* - * Drain each tg while doing post-order walk on the blkg tree, so - * that all bios are propagated to td->service_queue. It'd be - * better to walk service_queue tree directly but blkg walk is - * easier. - */ - blkg_for_each_descendant_post(blkg, pos_css, td->queue->root_blkg) - tg_drain_bios(&blkg_to_tg(blkg)->service_queue); - - /* finally, transfer bios from top-level tg's into the td */ - tg_drain_bios(&td->service_queue); - - rcu_read_unlock(); - spin_unlock_irq(&q->queue_lock); - - /* all bios now should be in td->service_queue, issue them */ - for (rw = READ; rw <= WRITE; rw++) - while ((bio = throtl_pop_queued(&td->service_queue.queued[rw], - NULL))) - generic_make_request(bio); - - spin_lock_irq(&q->queue_lock); -} - int blk_throtl_init(struct request_queue *q) { struct throtl_data *td; diff --git a/block/blk.h b/block/blk.h index 428f7e5d70a8..aa16e524dc35 100644 --- a/block/blk.h +++ b/block/blk.h @@ -296,12 +296,10 @@ int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node); * Internal throttling interface */ #ifdef CONFIG_BLK_DEV_THROTTLING -extern void blk_throtl_drain(struct request_queue *q); extern int blk_throtl_init(struct request_queue *q); extern void blk_throtl_exit(struct request_queue *q); extern void blk_throtl_register_queue(struct request_queue *q); #else /* CONFIG_BLK_DEV_THROTTLING */ -static inline void blk_throtl_drain(struct request_queue *q) { } static inline int blk_throtl_init(struct request_queue *q) { return 0; } static inline void blk_throtl_exit(struct request_queue *q) { } static inline void blk_throtl_register_queue(struct request_queue *q) { } -- cgit v1.2.3 From 32e3374304c7c317c05a61f3ddc315dbd46424f2 Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Sat, 9 May 2020 00:00:13 +0200 Subject: blk-throttle: remove tg_drain_bios After blk_throtl_drain is removed, there is no caller of tg_drain_bios, so remove it as well. Signed-off-by: Guoqing Jiang Signed-off-by: Jens Axboe --- block/blk-throttle.c | 22 ---------------------- 1 file changed, 22 deletions(-) (limited to 'block') diff --git a/block/blk-throttle.c b/block/blk-throttle.c index 0b2ce7fb77a7..209fdd8939fb 100644 --- a/block/blk-throttle.c +++ b/block/blk-throttle.c @@ -2358,28 +2358,6 @@ void blk_throtl_bio_endio(struct bio *bio) } #endif -/* - * Dispatch all bios from all children tg's queued on @parent_sq. On - * return, @parent_sq is guaranteed to not have any active children tg's - * and all bios from previously active tg's are on @parent_sq->bio_lists[]. - */ -static void tg_drain_bios(struct throtl_service_queue *parent_sq) -{ - struct throtl_grp *tg; - - while ((tg = throtl_rb_first(parent_sq))) { - struct throtl_service_queue *sq = &tg->service_queue; - struct bio *bio; - - throtl_dequeue_tg(tg); - - while ((bio = throtl_peek_queued(&sq->queued[READ]))) - tg_dispatch_one_bio(tg, bio_data_dir(bio)); - while ((bio = throtl_peek_queued(&sq->queued[WRITE]))) - tg_dispatch_one_bio(tg, bio_data_dir(bio)); - } -} - int blk_throtl_init(struct request_queue *q) { struct throtl_data *td; -- cgit v1.2.3 From 26e0ca12e07677ca5946ed98a1e41255016f6910 Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Sat, 9 May 2020 00:00:14 +0200 Subject: blk-wbt: remove wbt_update_limits No one call this function after commit 2af2783f2ea4f ("rq-qos: get rid of redundant wbt_update_limits()"), so remove it. Signed-off-by: Guoqing Jiang Signed-off-by: Jens Axboe --- block/blk-wbt.c | 8 -------- block/blk-wbt.h | 4 ---- 2 files changed, 12 deletions(-) (limited to 'block') diff --git a/block/blk-wbt.c b/block/blk-wbt.c index 9cb082f38b93..78bb624cce53 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -418,14 +418,6 @@ static void __wbt_update_limits(struct rq_wb *rwb) rwb_wake_all(rwb); } -void wbt_update_limits(struct request_queue *q) -{ - struct rq_qos *rqos = wbt_rq_qos(q); - if (!rqos) - return; - __wbt_update_limits(RQWB(rqos)); -} - u64 wbt_get_min_lat(struct request_queue *q) { struct rq_qos *rqos = wbt_rq_qos(q); diff --git a/block/blk-wbt.h b/block/blk-wbt.h index 8e4e37660971..16bdc85b8df9 100644 --- a/block/blk-wbt.h +++ b/block/blk-wbt.h @@ -88,7 +88,6 @@ static inline unsigned int wbt_inflight(struct rq_wb *rwb) #ifdef CONFIG_BLK_WBT int wbt_init(struct request_queue *); -void wbt_update_limits(struct request_queue *); void wbt_disable_default(struct request_queue *); void wbt_enable_default(struct request_queue *); @@ -108,9 +107,6 @@ static inline int wbt_init(struct request_queue *q) { return -EINVAL; } -static inline void wbt_update_limits(struct request_queue *q) -{ -} static inline void wbt_disable_default(struct request_queue *q) { } -- cgit v1.2.3 From 4d89e1d112a90e38032a4a1591c335947f471e95 Mon Sep 17 00:00:00 2001 From: Guoqing Jiang Date: Sat, 9 May 2020 00:00:15 +0200 Subject: blk-wbt: rename __wbt_update_limits to wbt_update_limits Now let's rename __wbt_update_limits to wbt_update_limits after the previous one is deleted. Signed-off-by: Guoqing Jiang Signed-off-by: Jens Axboe --- block/blk-wbt.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'block') diff --git a/block/blk-wbt.c b/block/blk-wbt.c index 78bb624cce53..0fa615eefd52 100644 --- a/block/blk-wbt.c +++ b/block/blk-wbt.c @@ -405,7 +405,7 @@ static void wb_timer_fn(struct blk_stat_callback *cb) rwb_arm_timer(rwb); } -static void __wbt_update_limits(struct rq_wb *rwb) +static void wbt_update_limits(struct rq_wb *rwb) { struct rq_depth *rqd = &rwb->rq_depth; @@ -433,7 +433,7 @@ void wbt_set_min_lat(struct request_queue *q, u64 val) return; RQWB(rqos)->min_lat_nsec = val; RQWB(rqos)->enable_state = WBT_STATE_ON_MANUAL; - __wbt_update_limits(RQWB(rqos)); + wbt_update_limits(RQWB(rqos)); } @@ -677,7 +677,7 @@ static int wbt_data_dir(const struct request *rq) static void wbt_queue_depth_changed(struct rq_qos *rqos) { RQWB(rqos)->rq_depth.queue_depth = blk_queue_depth(rqos->q); - __wbt_update_limits(RQWB(rqos)); + wbt_update_limits(RQWB(rqos)); } static void wbt_exit(struct rq_qos *rqos) @@ -835,7 +835,7 @@ int wbt_init(struct request_queue *q) rwb->enable_state = WBT_STATE_ON_DEFAULT; rwb->wc = 1; rwb->rq_depth.default_depth = RWB_DEF_DEPTH; - __wbt_update_limits(rwb); + wbt_update_limits(rwb); /* * Assign rwb and add the stats callback. -- cgit v1.2.3