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authorLinus Torvalds <torvalds@linux-foundation.org>2017-09-07 11:59:42 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-07 11:59:42 -0700
commita0725ab0c7536076d5477264420ef420ebb64501 (patch)
tree5c972d46c7f58f634ad74c6e4bc7a2bee24e5956 /block/genhd.c
parent3ee31b89d9b12c01aa03dda7a923ef07a800eedd (diff)
parentef13ecbc134d7e0ca4ab4834d08bd20885b53c62 (diff)
downloadlinux-0-day-a0725ab0c7536076d5477264420ef420ebb64501.tar.gz
Merge branch 'for-4.14/block' of git://git.kernel.dk/linux-block
Pull block layer updates from Jens Axboe: "This is the first pull request for 4.14, containing most of the code changes. It's a quiet series this round, which I think we needed after the churn of the last few series. This contains: - Fix for a registration race in loop, from Anton Volkov. - Overflow complaint fix from Arnd for DAC960. - Series of drbd changes from the usual suspects. - Conversion of the stec/skd driver to blk-mq. From Bart. - A few BFQ improvements/fixes from Paolo. - CFQ improvement from Ritesh, allowing idling for group idle. - A few fixes found by Dan's smatch, courtesy of Dan. - A warning fixup for a race between changing the IO scheduler and device remova. From David Jeffery. - A few nbd fixes from Josef. - Support for cgroup info in blktrace, from Shaohua. - Also from Shaohua, new features in the null_blk driver to allow it to actually hold data, among other things. - Various corner cases and error handling fixes from Weiping Zhang. - Improvements to the IO stats tracking for blk-mq from me. Can drastically improve performance for fast devices and/or big machines. - Series from Christoph removing bi_bdev as being needed for IO submission, in preparation for nvme multipathing code. - Series from Bart, including various cleanups and fixes for switch fall through case complaints" * 'for-4.14/block' of git://git.kernel.dk/linux-block: (162 commits) kernfs: checking for IS_ERR() instead of NULL drbd: remove BIOSET_NEED_RESCUER flag from drbd_{md_,}io_bio_set drbd: Fix allyesconfig build, fix recent commit drbd: switch from kmalloc() to kmalloc_array() drbd: abort drbd_start_resync if there is no connection drbd: move global variables to drbd namespace and make some static drbd: rename "usermode_helper" to "drbd_usermode_helper" drbd: fix race between handshake and admin disconnect/down drbd: fix potential deadlock when trying to detach during handshake drbd: A single dot should be put into a sequence. drbd: fix rmmod cleanup, remove _all_ debugfs entries drbd: Use setup_timer() instead of init_timer() to simplify the code. drbd: fix potential get_ldev/put_ldev refcount imbalance during attach drbd: new disk-option disable-write-same drbd: Fix resource role for newly created resources in events2 drbd: mark symbols static where possible drbd: Send P_NEG_ACK upon write error in protocol != C drbd: add explicit plugging when submitting batches drbd: change list_for_each_safe to while(list_first_entry_or_null) drbd: introduce drbd_recv_header_maybe_unplug ...
Diffstat (limited to 'block/genhd.c')
-rw-r--r--block/genhd.c91
1 files changed, 71 insertions, 20 deletions
diff --git a/block/genhd.c b/block/genhd.c
index 51c1d40..dd305c6 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -45,6 +45,52 @@ static void disk_add_events(struct gendisk *disk);
static void disk_del_events(struct gendisk *disk);
static void disk_release_events(struct gendisk *disk);
+void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, int rw)
+{
+ if (q->mq_ops)
+ return;
+
+ atomic_inc(&part->in_flight[rw]);
+ if (part->partno)
+ atomic_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 (q->mq_ops)
+ return;
+
+ atomic_dec(&part->in_flight[rw]);
+ if (part->partno)
+ atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
+}
+
+void part_in_flight(struct request_queue *q, struct hd_struct *part,
+ unsigned int inflight[2])
+{
+ if (q->mq_ops) {
+ blk_mq_in_flight(q, part, inflight);
+ return;
+ }
+
+ inflight[0] = atomic_read(&part->in_flight[0]) +
+ atomic_read(&part->in_flight[1]);
+ if (part->partno) {
+ part = &part_to_disk(part)->part0;
+ inflight[1] = atomic_read(&part->in_flight[0]) +
+ atomic_read(&part->in_flight[1]);
+ }
+}
+
+struct hd_struct *__disk_get_part(struct gendisk *disk, int partno)
+{
+ struct disk_part_tbl *ptbl = rcu_dereference(disk->part_tbl);
+
+ if (unlikely(partno < 0 || partno >= ptbl->len))
+ return NULL;
+ return rcu_dereference(ptbl->part[partno]);
+}
+
/**
* disk_get_part - get partition
* @disk: disk to look partition from
@@ -61,21 +107,12 @@ static void disk_release_events(struct gendisk *disk);
*/
struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
{
- struct hd_struct *part = NULL;
- struct disk_part_tbl *ptbl;
-
- if (unlikely(partno < 0))
- return NULL;
+ struct hd_struct *part;
rcu_read_lock();
-
- ptbl = rcu_dereference(disk->part_tbl);
- if (likely(partno < ptbl->len)) {
- part = rcu_dereference(ptbl->part[partno]);
- if (part)
- get_device(part_to_dev(part));
- }
-
+ part = __disk_get_part(disk, partno);
+ if (part)
+ get_device(part_to_dev(part));
rcu_read_unlock();
return part;
@@ -1098,12 +1135,13 @@ static const struct attribute_group *disk_attr_groups[] = {
* original ptbl is freed using RCU callback.
*
* LOCKING:
- * Matching bd_mutx locked.
+ * Matching bd_mutex locked or the caller is the only user of @disk.
*/
static void disk_replace_part_tbl(struct gendisk *disk,
struct disk_part_tbl *new_ptbl)
{
- struct disk_part_tbl *old_ptbl = disk->part_tbl;
+ struct disk_part_tbl *old_ptbl =
+ rcu_dereference_protected(disk->part_tbl, 1);
rcu_assign_pointer(disk->part_tbl, new_ptbl);
@@ -1122,14 +1160,16 @@ static void disk_replace_part_tbl(struct gendisk *disk,
* uses RCU to allow unlocked dereferencing for stats and other stuff.
*
* LOCKING:
- * Matching bd_mutex locked, might sleep.
+ * Matching bd_mutex locked or the caller is the only user of @disk.
+ * Might sleep.
*
* RETURNS:
* 0 on success, -errno on failure.
*/
int disk_expand_part_tbl(struct gendisk *disk, int partno)
{
- struct disk_part_tbl *old_ptbl = disk->part_tbl;
+ struct disk_part_tbl *old_ptbl =
+ rcu_dereference_protected(disk->part_tbl, 1);
struct disk_part_tbl *new_ptbl;
int len = old_ptbl ? old_ptbl->len : 0;
int i, target;
@@ -1212,6 +1252,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
struct disk_part_iter piter;
struct hd_struct *hd;
char buf[BDEVNAME_SIZE];
+ unsigned int inflight[2];
int cpu;
/*
@@ -1225,8 +1266,9 @@ 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))) {
cpu = part_stat_lock();
- part_round_stats(cpu, hd);
+ part_round_stats(gp->queue, cpu, hd);
part_stat_unlock();
+ part_in_flight(gp->queue, hd, inflight);
seq_printf(seqf, "%4d %7d %s %lu %lu %lu "
"%u %lu %lu %lu %u %u %u %u\n",
MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
@@ -1239,7 +1281,7 @@ static int diskstats_show(struct seq_file *seqf, void *v)
part_stat_read(hd, merges[WRITE]),
part_stat_read(hd, sectors[WRITE]),
jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])),
- part_in_flight(hd),
+ inflight[0],
jiffies_to_msecs(part_stat_read(hd, io_ticks)),
jiffies_to_msecs(part_stat_read(hd, time_in_queue))
);
@@ -1321,6 +1363,14 @@ EXPORT_SYMBOL(alloc_disk);
struct gendisk *alloc_disk_node(int minors, int node_id)
{
struct gendisk *disk;
+ struct disk_part_tbl *ptbl;
+
+ if (minors > DISK_MAX_PARTS) {
+ printk(KERN_ERR
+ "block: can't allocated more than %d partitions\n",
+ DISK_MAX_PARTS);
+ minors = DISK_MAX_PARTS;
+ }
disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
if (disk) {
@@ -1334,7 +1384,8 @@ struct gendisk *alloc_disk_node(int minors, int node_id)
kfree(disk);
return NULL;
}
- disk->part_tbl->part[0] = &disk->part0;
+ ptbl = rcu_dereference_protected(disk->part_tbl, 1);
+ rcu_assign_pointer(ptbl->part[0], &disk->part0);
/*
* set_capacity() and get_capacity() currently don't use