block: change ->make_request_fn() and users to return a queue cookie

No functional changes in this patch, but it prepares us for returning
a more useful cookie related to the IO that was queued up.

Signed-off-by: Jens Axboe <axboe@fb.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Keith Busch <keith.busch@intel.com>

19 files changed, 62 insertions, 41 deletions

diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index b9794aeeb878c..c9f9c30d64675 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -323,7 +323,7 @@ out:
 	return err;
 }
 
-static void brd_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct block_device *bdev = bio->bi_bdev;
 	struct brd_device *brd = bdev->bd_disk->private_data;
@@ -358,9 +358,10 @@ static void brd_make_request(struct request_queue *q, struct bio *bio)
 
 out:
 	bio_endio(bio);
-	return;
+	return BLK_QC_T_NONE;
 io_error:
 	bio_io_error(bio);
+	return BLK_QC_T_NONE;
 }
 
 static int brd_rw_page(struct block_device *bdev, sector_t sector,
diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index 015c6e91b7568..e66d453a5f2b1 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -1448,7 +1448,7 @@ extern int proc_details;
 /* drbd_req */
 extern void do_submit(struct work_struct *ws);
 extern void __drbd_make_request(struct drbd_device *, struct bio *, unsigned long);
-extern void drbd_make_request(struct request_queue *q, struct bio *bio);
+extern blk_qc_t drbd_make_request(struct request_queue *q, struct bio *bio);
 extern int drbd_read_remote(struct drbd_device *device, struct drbd_request *req);
 extern int is_valid_ar_handle(struct drbd_request *, sector_t);
 
diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index 2115926821696..3ae2c00865635 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -1494,7 +1494,7 @@ void do_submit(struct work_struct *ws)
 	}
 }
 
-void drbd_make_request(struct request_queue *q, struct bio *bio)
+blk_qc_t drbd_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct drbd_device *device = (struct drbd_device *) q->queuedata;
 	unsigned long start_jif;
@@ -1510,6 +1510,7 @@ void drbd_make_request(struct request_queue *q, struct bio *bio)
 
 	inc_ap_bio(device);
 	__drbd_make_request(device, bio, start_jif);
+	return BLK_QC_T_NONE;
 }
 
 void request_timer_fn(unsigned long data)
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 1c9e4fe5aa440..6255d1c4bba46 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -321,7 +321,7 @@ static struct nullb_queue *nullb_to_queue(struct nullb *nullb)
 	return &nullb->queues[index];
 }
 
-static void null_queue_bio(struct request_queue *q, struct bio *bio)
+static blk_qc_t null_queue_bio(struct request_queue *q, struct bio *bio)
 {
 	struct nullb *nullb = q->queuedata;
 	struct nullb_queue *nq = nullb_to_queue(nullb);
@@ -331,6 +331,7 @@ static void null_queue_bio(struct request_queue *q, struct bio *bio)
 	cmd->bio = bio;
 
 	null_handle_cmd(cmd);
+	return BLK_QC_T_NONE;
 }
 
 static int null_rq_prep_fn(struct request_queue *q, struct request *req)
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 7be2375db7f26..a7f4abcedee18 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2441,7 +2441,7 @@ static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
 	}
 }
 
-static void pkt_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t pkt_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct pktcdvd_device *pd;
 	char b[BDEVNAME_SIZE];
@@ -2467,7 +2467,7 @@ static void pkt_make_request(struct request_queue *q, struct bio *bio)
 	 */
 	if (bio_data_dir(bio) == READ) {
 		pkt_make_request_read(pd, bio);
-		return;
+		return BLK_QC_T_NONE;
 	}
 
 	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
@@ -2499,13 +2499,12 @@ static void pkt_make_request(struct request_queue *q, struct bio *bio)
 		pkt_make_request_write(q, split);
 	} while (split != bio);
 
-	return;
+	return BLK_QC_T_NONE;
 end_io:
 	bio_io_error(bio);
+	return BLK_QC_T_NONE;
 }
 
-
-
 static void pkt_init_queue(struct pktcdvd_device *pd)
 {
 	struct request_queue *q = pd->disk->queue;
diff --git a/drivers/block/ps3vram.c b/drivers/block/ps3vram.c
index d89fcac595151..56847fcda0860 100644
--- a/drivers/block/ps3vram.c
+++ b/drivers/block/ps3vram.c
@@ -598,7 +598,7 @@ out:
 	return next;
 }
 
-static void ps3vram_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t ps3vram_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct ps3_system_bus_device *dev = q->queuedata;
 	struct ps3vram_priv *priv = ps3_system_bus_get_drvdata(dev);
@@ -614,11 +614,13 @@ static void ps3vram_make_request(struct request_queue *q, struct bio *bio)
 	spin_unlock_irq(&priv->lock);
 
 	if (busy)
-		return;
+		return BLK_QC_T_NONE;
 
 	do {
 		bio = ps3vram_do_bio(dev, bio);
 	} while (bio);
+
+	return BLK_QC_T_NONE;
 }
 
 static int ps3vram_probe(struct ps3_system_bus_device *dev)
diff --git a/drivers/block/rsxx/dev.c b/drivers/block/rsxx/dev.c
index 3163e4cdc2cc5..e1b8b7061d2f8 100644
--- a/drivers/block/rsxx/dev.c
+++ b/drivers/block/rsxx/dev.c
@@ -145,7 +145,7 @@ static void bio_dma_done_cb(struct rsxx_cardinfo *card,
 	}
 }
 
-static void rsxx_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t rsxx_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct rsxx_cardinfo *card = q->queuedata;
 	struct rsxx_bio_meta *bio_meta;
@@ -199,7 +199,7 @@ static void rsxx_make_request(struct request_queue *q, struct bio *bio)
 	if (st)
 		goto queue_err;
 
-	return;
+	return BLK_QC_T_NONE;
 
 queue_err:
 	kmem_cache_free(bio_meta_pool, bio_meta);
@@ -207,6 +207,7 @@ req_err:
 	if (st)
 		bio->bi_error = st;
 	bio_endio(bio);
+	return BLK_QC_T_NONE;
 }
 
 /*----------------- Device Setup -------------------*/
diff --git a/drivers/block/umem.c b/drivers/block/umem.c
index 04d65790a8862..7939b9f874413 100644
--- a/drivers/block/umem.c
+++ b/drivers/block/umem.c
@@ -524,7 +524,7 @@ static int mm_check_plugged(struct cardinfo *card)
 	return !!blk_check_plugged(mm_unplug, card, sizeof(struct blk_plug_cb));
 }
 
-static void mm_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t mm_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct cardinfo *card = q->queuedata;
 	pr_debug("mm_make_request %llu %u\n",
@@ -541,7 +541,7 @@ static void mm_make_request(struct request_queue *q, struct bio *bio)
 		activate(card);
 	spin_unlock_irq(&card->lock);
 
-	return;
+	return BLK_QC_T_NONE;
 }
 
 static irqreturn_t mm_interrupt(int irq, void *__card)
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 9fa15bb9d118e..4c99b6ba86813 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -894,7 +894,7 @@ out:
 /*
  * Handler function for all zram I/O requests.
  */
-static void zram_make_request(struct request_queue *queue, struct bio *bio)
+static blk_qc_t zram_make_request(struct request_queue *queue, struct bio *bio)
 {
 	struct zram *zram = queue->queuedata;
 
@@ -911,11 +911,12 @@ static void zram_make_request(struct request_queue *queue, struct bio *bio)
 
 	__zram_make_request(zram, bio);
 	zram_meta_put(zram);
-	return;
+	return BLK_QC_T_NONE;
 put_zram:
 	zram_meta_put(zram);
 error:
 	bio_io_error(bio);
+	return BLK_QC_T_NONE;
 }
 
 static void zram_slot_free_notify(struct block_device *bdev,
diff --git a/drivers/lightnvm/rrpc.c b/drivers/lightnvm/rrpc.c
index 64a888a5e9b3d..7ba64c87ba1c1 100644
--- a/drivers/lightnvm/rrpc.c
+++ b/drivers/lightnvm/rrpc.c
@@ -803,7 +803,7 @@ static int rrpc_submit_io(struct rrpc *rrpc, struct bio *bio,
 	return NVM_IO_OK;
 }
 
-static void rrpc_make_rq(struct request_queue *q, struct bio *bio)
+static blk_qc_t rrpc_make_rq(struct request_queue *q, struct bio *bio)
 {
 	struct rrpc *rrpc = q->queuedata;
 	struct nvm_rq *rqd;
@@ -811,21 +811,21 @@ static void rrpc_make_rq(struct request_queue *q, struct bio *bio)
 
 	if (bio->bi_rw & REQ_DISCARD) {
 		rrpc_discard(rrpc, bio);
-		return;
+		return BLK_QC_T_NONE;
 	}
 
 	rqd = mempool_alloc(rrpc->rq_pool, GFP_KERNEL);
 	if (!rqd) {
 		pr_err_ratelimited("rrpc: not able to queue bio.");
 		bio_io_error(bio);
-		return;
+		return BLK_QC_T_NONE;
 	}
 	memset(rqd, 0, sizeof(struct nvm_rq));
 
 	err = rrpc_submit_io(rrpc, bio, rqd, NVM_IOTYPE_NONE);
 	switch (err) {
 	case NVM_IO_OK:
-		return;
+		return BLK_QC_T_NONE;
 	case NVM_IO_ERR:
 		bio_io_error(bio);
 		break;
@@ -841,6 +841,7 @@ static void rrpc_make_rq(struct request_queue *q, struct bio *bio)
 	}
 
 	mempool_free(rqd, rrpc->rq_pool);
+	return BLK_QC_T_NONE;
 }
 
 static void rrpc_requeue(struct work_struct *work)
diff --git a/drivers/md/bcache/request.c b/drivers/md/bcache/request.c
index 8e9877b046371..25fa8445bb242 100644
--- a/drivers/md/bcache/request.c
+++ b/drivers/md/bcache/request.c
@@ -958,7 +958,8 @@ static void cached_dev_nodata(struct closure *cl)
 
 /* Cached devices - read & write stuff */
 
-static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t cached_dev_make_request(struct request_queue *q,
+					struct bio *bio)
 {
 	struct search *s;
 	struct bcache_device *d = bio->bi_bdev->bd_disk->private_data;
@@ -997,6 +998,8 @@ static void cached_dev_make_request(struct request_queue *q, struct bio *bio)
 		else
 			generic_make_request(bio);
 	}
+
+	return BLK_QC_T_NONE;
 }
 
 static int cached_dev_ioctl(struct bcache_device *d, fmode_t mode,
@@ -1070,7 +1073,8 @@ static void flash_dev_nodata(struct closure *cl)
 	continue_at(cl, search_free, NULL);
 }
 
-static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t flash_dev_make_request(struct request_queue *q,
+					     struct bio *bio)
 {
 	struct search *s;
 	struct closure *cl;
@@ -1093,7 +1097,7 @@ static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
 		continue_at_nobarrier(&s->cl,
 				      flash_dev_nodata,
 				      bcache_wq);
-		return;
+		return BLK_QC_T_NONE;
 	} else if (rw) {
 		bch_keybuf_check_overlapping(&s->iop.c->moving_gc_keys,
 					&KEY(d->id, bio->bi_iter.bi_sector, 0),
@@ -1109,6 +1113,7 @@ static void flash_dev_make_request(struct request_queue *q, struct bio *bio)
 	}
 
 	continue_at(cl, search_free, NULL);
+	return BLK_QC_T_NONE;
 }
 
 static int flash_dev_ioctl(struct bcache_device *d, fmode_t mode,
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 32440ad5f6844..6e15f3565892f 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1755,7 +1755,7 @@ static void __split_and_process_bio(struct mapped_device *md,
  * The request function that just remaps the bio built up by
  * dm_merge_bvec.
  */
-static void dm_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
 {
 	int rw = bio_data_dir(bio);
 	struct mapped_device *md = q->queuedata;
@@ -1774,12 +1774,12 @@ static void dm_make_request(struct request_queue *q, struct bio *bio)
 			queue_io(md, bio);
 		else
 			bio_io_error(bio);
-		return;
+		return BLK_QC_T_NONE;
 	}
 
 	__split_and_process_bio(md, map, bio);
 	dm_put_live_table(md, srcu_idx);
-	return;
+	return BLK_QC_T_NONE;
 }
 
 int dm_request_based(struct mapped_device *md)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3f9a514b5b9d7..807095f4c793b 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -250,7 +250,7 @@ static DEFINE_SPINLOCK(all_mddevs_lock);
  * call has finished, the bio has been linked into some internal structure
  * and so is visible to ->quiesce(), so we don't need the refcount any more.
  */
-static void md_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t md_make_request(struct request_queue *q, struct bio *bio)
 {
 	const int rw = bio_data_dir(bio);
 	struct mddev *mddev = q->queuedata;
@@ -262,13 +262,13 @@ static void md_make_request(struct request_queue *q, struct bio *bio)
 	if (mddev == NULL || mddev->pers == NULL
 	    || !mddev->ready) {
 		bio_io_error(bio);
-		return;
+		return BLK_QC_T_NONE;
 	}
 	if (mddev->ro == 1 && unlikely(rw == WRITE)) {
 		if (bio_sectors(bio) != 0)
 			bio->bi_error = -EROFS;
 		bio_endio(bio);
-		return;
+		return BLK_QC_T_NONE;
 	}
 	smp_rmb(); /* Ensure implications of  'active' are visible */
 	rcu_read_lock();
@@ -302,6 +302,8 @@ static void md_make_request(struct request_queue *q, struct bio *bio)
 
 	if (atomic_dec_and_test(&mddev->active_io) && mddev->suspended)
 		wake_up(&mddev->sb_wait);
+
+	return BLK_QC_T_NONE;
 }
 
 /* mddev_suspend makes sure no new requests are submitted
diff --git a/drivers/nvdimm/blk.c b/drivers/nvdimm/blk.c
index 0df77cb07df64..91a336ea8c4f2 100644
--- a/drivers/nvdimm/blk.c
+++ b/drivers/nvdimm/blk.c
@@ -161,7 +161,7 @@ static int nd_blk_do_bvec(struct nd_blk_device *blk_dev,
 	return err;
 }
 
-static void nd_blk_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t nd_blk_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct block_device *bdev = bio->bi_bdev;
 	struct gendisk *disk = bdev->bd_disk;
@@ -208,6 +208,7 @@ static void nd_blk_make_request(struct request_queue *q, struct bio *bio)
 
  out:
 	bio_endio(bio);
+	return BLK_QC_T_NONE;
 }
 
 static int nd_blk_rw_bytes(struct nd_namespace_common *ndns,
diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index eae93ab8ffcde..efb2c1ceef989 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -1150,7 +1150,7 @@ static int btt_do_bvec(struct btt *btt, struct bio_integrity_payload *bip,
 	return ret;
 }
 
-static void btt_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t btt_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct bio_integrity_payload *bip = bio_integrity(bio);
 	struct btt *btt = q->queuedata;
@@ -1198,6 +1198,7 @@ static void btt_make_request(struct request_queue *q, struct bio *bio)
 
 out:
 	bio_endio(bio);
+	return BLK_QC_T_NONE;
 }
 
 static int btt_rw_page(struct block_device *bdev, sector_t sector,
diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index 0ba6a978f227e..3963b7533b652 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -64,7 +64,7 @@ static void pmem_do_bvec(struct pmem_device *pmem, struct page *page,
 	kunmap_atomic(mem);
 }
 
-static void pmem_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t pmem_make_request(struct request_queue *q, struct bio *bio)
 {
 	bool do_acct;
 	unsigned long start;
@@ -84,6 +84,7 @@ static void pmem_make_request(struct request_queue *q, struct bio *bio)
 		wmb_pmem();
 
 	bio_endio(bio);
+	return BLK_QC_T_NONE;
 }
 
 static int pmem_rw_page(struct block_device *bdev, sector_t sector,
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 5ed44fe213806..94a8f4ab57bc4 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -27,7 +27,8 @@
 
 static int dcssblk_open(struct block_device *bdev, fmode_t mode);
 static void dcssblk_release(struct gendisk *disk, fmode_t mode);
-static void dcssblk_make_request(struct request_queue *q, struct bio *bio);
+static blk_qc_t dcssblk_make_request(struct request_queue *q,
+						struct bio *bio);
 static long dcssblk_direct_access(struct block_device *bdev, sector_t secnum,
 			 void __pmem **kaddr, unsigned long *pfn);
 
@@ -815,7 +816,7 @@ dcssblk_release(struct gendisk *disk, fmode_t mode)
 	up_write(&dcssblk_devices_sem);
 }
 
-static void
+static blk_qc_t
 dcssblk_make_request(struct request_queue *q, struct bio *bio)
 {
 	struct dcssblk_dev_info *dev_info;
@@ -874,9 +875,10 @@ dcssblk_make_request(struct request_queue *q, struct bio *bio)
 		bytes_done += bvec.bv_len;
 	}
 	bio_endio(bio);
-	return;
+	return BLK_QC_T_NONE;
 fail:
 	bio_io_error(bio);
+	return BLK_QC_T_NONE;
 }
 
 static long
diff --git a/drivers/s390/block/xpram.c b/drivers/s390/block/xpram.c
index 02871f1db562e..288f59a4147b1 100644
--- a/drivers/s390/block/xpram.c
+++ b/drivers/s390/block/xpram.c
@@ -181,7 +181,7 @@ static unsigned long xpram_highest_page_index(void)
 /*
  * Block device make request function.
  */
-static void xpram_make_request(struct request_queue *q, struct bio *bio)
+static blk_qc_t xpram_make_request(struct request_queue *q, struct bio *bio)
 {
 	xpram_device_t *xdev = bio->bi_bdev->bd_disk->private_data;
 	struct bio_vec bvec;
@@ -223,9 +223,10 @@ static void xpram_make_request(struct request_queue *q, struct bio *bio)
 		}
 	}
 	bio_endio(bio);
-	return;
+	return BLK_QC_T_NONE;
 fail:
 	bio_io_error(bio);
+	return BLK_QC_T_NONE;
 }
 
 static int xpram_getgeo(struct block_device *bdev, struct hd_geometry *geo)
diff --git a/drivers/staging/lustre/lustre/llite/lloop.c b/drivers/staging/lustre/lustre/llite/lloop.c
index e6974c36276d7..fed50d538a414 100644
--- a/drivers/staging/lustre/lustre/llite/lloop.c
+++ b/drivers/staging/lustre/lustre/llite/lloop.c
@@ -333,7 +333,7 @@ static unsigned int loop_get_bio(struct lloop_device *lo, struct bio **req)
 	return count;
 }
 
-static void loop_make_request(struct request_queue *q, struct bio *old_bio)
+static blk_qc_t loop_make_request(struct request_queue *q, struct bio *old_bio)
 {
 	struct lloop_device *lo = q->queuedata;
 	int rw = bio_rw(old_bio);
@@ -364,9 +364,10 @@ static void loop_make_request(struct request_queue *q, struct bio *old_bio)
 		goto err;
 	}
 	loop_add_bio(lo, old_bio);
-	return;
+	return BLK_QC_T_NONE;
 err:
 	bio_io_error(old_bio);
+	return BLK_QC_T_NONE;
 }
 
 static inline void loop_handle_bio(struct lloop_device *lo, struct bio *bio)