Merge tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block

Pull more block updates from Jens Axboe:
 "A few stragglers (and one due to me missing it originally), and fixes
  for changes in this merge window mostly. In particular:

   - blktrace cleanups (Chaitanya, Greg)

   - Kill dead blk_pm_* functions (Bart)

   - Fixes for the bio alloc changes (Christoph)

   - Fix for the partition changes (Christoph, Ming)

   - Fix for turning off iopoll with polled IO inflight (Jeffle)

   - nbd disconnect fix (Josef)

   - loop fsync error fix (Mauricio)

   - kyber update depth fix (Yang)

   - max_sectors alignment fix (Mikulas)

   - Add bio_max_segs helper (Matthew)"

* tag 'block-5.12-2021-02-27' of git://git.kernel.dk/linux-block: (21 commits)
  block: Add bio_max_segs
  blktrace: fix documentation for blk_fill_rw()
  block: memory allocations in bounce_clone_bio must not fail
  block: remove the gfp_mask argument to bounce_clone_bio
  block: fix bounce_clone_bio for passthrough bios
  block-crypto-fallback: use a bio_set for splitting bios
  block: fix logging on capacity change
  blk-settings: align max_sectors on "logical_block_size" boundary
  block: reopen the device in blkdev_reread_part
  block: don't skip empty device in in disk_uevent
  blktrace: remove debugfs file dentries from struct blk_trace
  nbd: handle device refs for DESTROY_ON_DISCONNECT properly
  kyber: introduce kyber_depth_updated()
  loop: fix I/O error on fsync() in detached loop devices
  block: fix potential IO hang when turning off io_poll
  block: get rid of the trace rq insert wrapper
  blktrace: fix blk_rq_merge documentation
  blktrace: fix blk_rq_issue documentation
  blktrace: add blk_fill_rwbs documentation comment
  block: remove superfluous param in blk_fill_rwbs()
  ...

40 files changed, 173 insertions, 180 deletions

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index b398dde53af9..ec482e6641ff 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -125,6 +125,8 @@
 #include <linux/delay.h>
 #include <linux/backing-dev.h>
 
+#include <trace/events/block.h>
+
 #include "blk.h"
 #include "blk-mq.h"
 #include "blk-mq-tag.h"
@@ -5621,7 +5623,7 @@ static void bfq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
 
 	spin_unlock_irq(&bfqd->lock);
 
-	blk_mq_sched_request_inserted(rq);
+	trace_block_rq_insert(rq);
 
 	spin_lock_irq(&bfqd->lock);
 	bfqq = bfq_init_rq(rq);
diff --git a/block/blk-core.c b/block/blk-core.c
index 5e752840b41a..fc60ff208497 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -59,6 +59,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_split);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug);
+EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_insert);
 
 DEFINE_IDA(blk_queue_ida);
 
diff --git a/block/blk-crypto-fallback.c b/block/blk-crypto-fallback.c
index e8327c50d7c9..c176b7af56a7 100644
--- a/block/blk-crypto-fallback.c
+++ b/block/blk-crypto-fallback.c
@@ -80,6 +80,7 @@ static struct blk_crypto_keyslot {
 static struct blk_keyslot_manager blk_crypto_ksm;
 static struct workqueue_struct *blk_crypto_wq;
 static mempool_t *blk_crypto_bounce_page_pool;
+static struct bio_set crypto_bio_split;
 
 /*
  * This is the key we set when evicting a keyslot. This *should* be the all 0's
@@ -224,7 +225,8 @@ static bool blk_crypto_split_bio_if_needed(struct bio **bio_ptr)
 	if (num_sectors < bio_sectors(bio)) {
 		struct bio *split_bio;
 
-		split_bio = bio_split(bio, num_sectors, GFP_NOIO, NULL);
+		split_bio = bio_split(bio, num_sectors, GFP_NOIO,
+				      &crypto_bio_split);
 		if (!split_bio) {
 			bio->bi_status = BLK_STS_RESOURCE;
 			return false;
@@ -538,9 +540,13 @@ static int blk_crypto_fallback_init(void)
 
 	prandom_bytes(blank_key, BLK_CRYPTO_MAX_KEY_SIZE);
 
-	err = blk_ksm_init(&blk_crypto_ksm, blk_crypto_num_keyslots);
+	err = bioset_init(&crypto_bio_split, 64, 0, 0);
 	if (err)
 		goto out;
+
+	err = blk_ksm_init(&blk_crypto_ksm, blk_crypto_num_keyslots);
+	if (err)
+		goto fail_free_bioset;
 	err = -ENOMEM;
 
 	blk_crypto_ksm.ksm_ll_ops = blk_crypto_ksm_ll_ops;
@@ -591,6 +597,8 @@ fail_free_wq:
 	destroy_workqueue(blk_crypto_wq);
 fail_free_ksm:
 	blk_ksm_destroy(&blk_crypto_ksm);
+fail_free_bioset:
+	bioset_exit(&crypto_bio_split);
 out:
 	return err;
 }
diff --git a/block/blk-map.c b/block/blk-map.c
index 21630dccac62..369e204d14d0 100644
--- a/block/blk-map.c
+++ b/block/blk-map.c
@@ -150,9 +150,7 @@ static int bio_copy_user_iov(struct request *rq, struct rq_map_data *map_data,
 	bmd->is_our_pages = !map_data;
 	bmd->is_null_mapped = (map_data && map_data->null_mapped);
 
-	nr_pages = DIV_ROUND_UP(offset + len, PAGE_SIZE);
-	if (nr_pages > BIO_MAX_PAGES)
-		nr_pages = BIO_MAX_PAGES;
+	nr_pages = bio_max_segs(DIV_ROUND_UP(offset + len, PAGE_SIZE));
 
 	ret = -ENOMEM;
 	bio = bio_kmalloc(gfp_mask, nr_pages);
diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index deff4e826e23..ddb65e9e6fd9 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -384,12 +384,6 @@ bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq)
 }
 EXPORT_SYMBOL_GPL(blk_mq_sched_try_insert_merge);
 
-void blk_mq_sched_request_inserted(struct request *rq)
-{
-	trace_block_rq_insert(rq);
-}
-EXPORT_SYMBOL_GPL(blk_mq_sched_request_inserted);
-
 static bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx,
 				       bool has_sched,
 				       struct request *rq)
diff --git a/block/blk-mq-sched.h b/block/blk-mq-sched.h
index 0476360f05f1..5b18ab915c65 100644
--- a/block/blk-mq-sched.h
+++ b/block/blk-mq-sched.h
@@ -7,7 +7,6 @@
 
 void blk_mq_sched_assign_ioc(struct request *rq);
 
-void blk_mq_sched_request_inserted(struct request *rq);
 bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,
 		unsigned int nr_segs, struct request **merged_request);
 bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
diff --git a/block/blk-pm.h b/block/blk-pm.h
index a2283cc9f716..8a5a0d4b357f 100644
--- a/block/blk-pm.h
+++ b/block/blk-pm.h
@@ -21,31 +21,6 @@ static inline void blk_pm_mark_last_busy(struct request *rq)
 	if (rq->q->dev && !(rq->rq_flags & RQF_PM))
 		pm_runtime_mark_last_busy(rq->q->dev);
 }
-
-static inline void blk_pm_requeue_request(struct request *rq)
-{
-	lockdep_assert_held(&rq->q->queue_lock);
-
-	if (rq->q->dev && !(rq->rq_flags & RQF_PM))
-		rq->q->nr_pending--;
-}
-
-static inline void blk_pm_add_request(struct request_queue *q,
-				      struct request *rq)
-{
-	lockdep_assert_held(&q->queue_lock);
-
-	if (q->dev && !(rq->rq_flags & RQF_PM))
-		q->nr_pending++;
-}
-
-static inline void blk_pm_put_request(struct request *rq)
-{
-	lockdep_assert_held(&rq->q->queue_lock);
-
-	if (rq->q->dev && !(rq->rq_flags & RQF_PM))
-		--rq->q->nr_pending;
-}
 #else
 static inline int blk_pm_resume_queue(const bool pm, struct request_queue *q)
 {
@@ -55,19 +30,6 @@ static inline int blk_pm_resume_queue(const bool pm, struct request_queue *q)
 static inline void blk_pm_mark_last_busy(struct request *rq)
 {
 }
-
-static inline void blk_pm_requeue_request(struct request *rq)
-{
-}
-
-static inline void blk_pm_add_request(struct request_queue *q,
-				      struct request *rq)
-{
-}
-
-static inline void blk_pm_put_request(struct request *rq)
-{
-}
 #endif
 
 #endif /* _BLOCK_BLK_PM_H_ */
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 7dd8be314ac6..b4aa2f37fab6 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -504,6 +504,14 @@ void blk_queue_io_opt(struct request_queue *q, unsigned int opt)
 }
 EXPORT_SYMBOL(blk_queue_io_opt);
 
+static unsigned int blk_round_down_sectors(unsigned int sectors, unsigned int lbs)
+{
+	sectors = round_down(sectors, lbs >> SECTOR_SHIFT);
+	if (sectors < PAGE_SIZE >> SECTOR_SHIFT)
+		sectors = PAGE_SIZE >> SECTOR_SHIFT;
+	return sectors;
+}
+
 /**
  * blk_stack_limits - adjust queue_limits for stacked devices
  * @t:	the stacking driver limits (top device)
@@ -630,6 +638,10 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 		ret = -1;
 	}
 
+	t->max_sectors = blk_round_down_sectors(t->max_sectors, t->logical_block_size);
+	t->max_hw_sectors = blk_round_down_sectors(t->max_hw_sectors, t->logical_block_size);
+	t->max_dev_sectors = blk_round_down_sectors(t->max_dev_sectors, t->logical_block_size);
+
 	/* Discard alignment and granularity */
 	if (b->discard_granularity) {
 		alignment = queue_limit_discard_alignment(b, start);
diff --git a/block/blk-sysfs.c b/block/blk-sysfs.c
index ae39c7f3d83d..0f4f0c8a7825 100644
--- a/block/blk-sysfs.c
+++ b/block/blk-sysfs.c
@@ -434,10 +434,13 @@ static ssize_t queue_poll_store(struct request_queue *q, const char *page,
 	if (ret < 0)
 		return ret;
 
-	if (poll_on)
+	if (poll_on) {
 		blk_queue_flag_set(QUEUE_FLAG_POLL, q);
-	else
+	} else {
+		blk_mq_freeze_queue(q);
 		blk_queue_flag_clear(QUEUE_FLAG_POLL, q);
+		blk_mq_unfreeze_queue(q);
+	}
 
 	return ret;
 }
diff --git a/block/bounce.c b/block/bounce.c
index fc55314aa426..87983a35079c 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -214,8 +214,7 @@ static void bounce_end_io_read_isa(struct bio *bio)
 	__bounce_end_io_read(bio, &isa_page_pool);
 }
 
-static struct bio *bounce_clone_bio(struct bio *bio_src, gfp_t gfp_mask,
-		struct bio_set *bs)
+static struct bio *bounce_clone_bio(struct bio *bio_src)
 {
 	struct bvec_iter iter;
 	struct bio_vec bv;
@@ -242,10 +241,12 @@ static struct bio *bounce_clone_bio(struct bio *bio_src, gfp_t gfp_mask,
 	 *    asking for trouble and would force extra work on
 	 *    __bio_clone_fast() anyways.
 	 */
-
-	bio = bio_alloc_bioset(gfp_mask, bio_segments(bio_src), bs);
-	if (!bio)
-		return NULL;
+	if (bio_is_passthrough(bio_src))
+		bio = bio_kmalloc(GFP_NOIO | __GFP_NOFAIL,
+				  bio_segments(bio_src));
+	else
+		bio = bio_alloc_bioset(GFP_NOIO, bio_segments(bio_src),
+				       &bounce_bio_set);
 	bio->bi_bdev		= bio_src->bi_bdev;
 	if (bio_flagged(bio_src, BIO_REMAPPED))
 		bio_set_flag(bio, BIO_REMAPPED);
@@ -269,11 +270,11 @@ static struct bio *bounce_clone_bio(struct bio *bio_src, gfp_t gfp_mask,
 		break;
 	}
 
-	if (bio_crypt_clone(bio, bio_src, gfp_mask) < 0)
+	if (bio_crypt_clone(bio, bio_src, GFP_NOIO) < 0)
 		goto err_put;
 
 	if (bio_integrity(bio_src) &&
-	    bio_integrity_clone(bio, bio_src, gfp_mask) < 0)
+	    bio_integrity_clone(bio, bio_src, GFP_NOIO) < 0)
 		goto err_put;
 
 	bio_clone_blkg_association(bio, bio_src);
@@ -296,7 +297,6 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
 	unsigned i = 0;
 	bool bounce = false;
 	int sectors = 0;
-	bool passthrough = bio_is_passthrough(*bio_orig);
 
 	bio_for_each_segment(from, *bio_orig, iter) {
 		if (i++ < BIO_MAX_PAGES)
@@ -307,14 +307,14 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
 	if (!bounce)
 		return;
 
-	if (!passthrough && sectors < bio_sectors(*bio_orig)) {
+	if (!bio_is_passthrough(*bio_orig) &&
+	    sectors < bio_sectors(*bio_orig)) {
 		bio = bio_split(*bio_orig, sectors, GFP_NOIO, &bounce_bio_split);
 		bio_chain(bio, *bio_orig);
 		submit_bio_noacct(*bio_orig);
 		*bio_orig = bio;
 	}
-	bio = bounce_clone_bio(*bio_orig, GFP_NOIO, passthrough ? NULL :
-			&bounce_bio_set);
+	bio = bounce_clone_bio(*bio_orig);
 
 	/*
 	 * Bvec table can't be updated by bio_for_each_segment_all(),
diff --git a/block/genhd.c b/block/genhd.c
index 36ff45bbaaaf..fcc530164b5a 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -74,7 +74,7 @@ bool set_capacity_and_notify(struct gendisk *disk, sector_t size)
 		return false;
 
 	pr_info("%s: detected capacity change from %lld to %lld\n",
-		disk->disk_name, size, capacity);
+		disk->disk_name, capacity, size);
 
 	/*
 	 * Historically we did not send a uevent for changes to/from an empty
@@ -476,7 +476,7 @@ void disk_uevent(struct gendisk *disk, enum kobject_action action)
 	struct disk_part_iter piter;
 	struct block_device *part;
 
-	disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
+	disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY_PART0);
 	while ((part = disk_part_iter_next(&piter)))
 		kobject_uevent(bdev_kobj(part), action);
 	disk_part_iter_exit(&piter);
diff --git a/block/ioctl.c b/block/ioctl.c
index d61d652078f4..ff241e663c01 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -81,20 +81,27 @@ static int compat_blkpg_ioctl(struct block_device *bdev,
 }
 #endif
 
-static int blkdev_reread_part(struct block_device *bdev)
+static int blkdev_reread_part(struct block_device *bdev, fmode_t mode)
 {
-	int ret;
+	struct block_device *tmp;
 
 	if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev))
 		return -EINVAL;
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	mutex_lock(&bdev->bd_mutex);
-	ret = bdev_disk_changed(bdev, false);
-	mutex_unlock(&bdev->bd_mutex);
+	/*
+	 * Reopen the device to revalidate the driver state and force a
+	 * partition rescan.
+	 */
+	mode &= ~FMODE_EXCL;
+	set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
 
-	return ret;
+	tmp = blkdev_get_by_dev(bdev->bd_dev, mode, NULL);
+	if (IS_ERR(tmp))
+		return PTR_ERR(tmp);
+	blkdev_put(tmp, mode);
+	return 0;
 }
 
 static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
@@ -498,7 +505,7 @@ static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode,
 		bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
 		return 0;
 	case BLKRRPART:
-		return blkdev_reread_part(bdev);
+		return blkdev_reread_part(bdev, mode);
 	case BLKTRACESTART:
 	case BLKTRACESTOP:
 	case BLKTRACETEARDOWN:
diff --git a/block/kyber-iosched.c b/block/kyber-iosched.c
index c25c41d0d061..33d34d69cade 100644
--- a/block/kyber-iosched.c
+++ b/block/kyber-iosched.c
@@ -13,6 +13,8 @@
 #include <linux/module.h>
 #include <linux/sbitmap.h>
 
+#include <trace/events/block.h>
+
 #include "blk.h"
 #include "blk-mq.h"
 #include "blk-mq-debugfs.h"
@@ -353,19 +355,9 @@ static void kyber_timer_fn(struct timer_list *t)
 	}
 }
 
-static unsigned int kyber_sched_tags_shift(struct request_queue *q)
-{
-	/*
-	 * All of the hardware queues have the same depth, so we can just grab
-	 * the shift of the first one.
-	 */
-	return q->queue_hw_ctx[0]->sched_tags->bitmap_tags->sb.shift;
-}
-
 static struct kyber_queue_data *kyber_queue_data_alloc(struct request_queue *q)
 {
 	struct kyber_queue_data *kqd;
-	unsigned int shift;
 	int ret = -ENOMEM;
 	int i;
 
@@ -400,9 +392,6 @@ static struct kyber_queue_data *kyber_queue_data_alloc(struct request_queue *q)
 		kqd->latency_targets[i] = kyber_latency_targets[i];
 	}
 
-	shift = kyber_sched_tags_shift(q);
-	kqd->async_depth = (1U << shift) * KYBER_ASYNC_PERCENT / 100U;
-
 	return kqd;
 
 err_buckets:
@@ -458,9 +447,19 @@ static void kyber_ctx_queue_init(struct kyber_ctx_queue *kcq)
 		INIT_LIST_HEAD(&kcq->rq_list[i]);
 }
 
-static int kyber_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
+static void kyber_depth_updated(struct blk_mq_hw_ctx *hctx)
 {
 	struct kyber_queue_data *kqd = hctx->queue->elevator->elevator_data;
+	struct blk_mq_tags *tags = hctx->sched_tags;
+	unsigned int shift = tags->bitmap_tags->sb.shift;
+
+	kqd->async_depth = (1U << shift) * KYBER_ASYNC_PERCENT / 100U;
+
+	sbitmap_queue_min_shallow_depth(tags->bitmap_tags, kqd->async_depth);
+}
+
+static int kyber_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
+{
 	struct kyber_hctx_data *khd;
 	int i;
 
@@ -502,8 +501,7 @@ static int kyber_init_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_idx)
 	khd->batching = 0;
 
 	hctx->sched_data = khd;
-	sbitmap_queue_min_shallow_depth(hctx->sched_tags->bitmap_tags,
-					kqd->async_depth);
+	kyber_depth_updated(hctx);
 
 	return 0;
 
@@ -602,7 +600,7 @@ static void kyber_insert_requests(struct blk_mq_hw_ctx *hctx,
 			list_move_tail(&rq->queuelist, head);
 		sbitmap_set_bit(&khd->kcq_map[sched_domain],
 				rq->mq_ctx->index_hw[hctx->type]);
-		blk_mq_sched_request_inserted(rq);
+		trace_block_rq_insert(rq);
 		spin_unlock(&kcq->lock);
 	}
 }
@@ -1022,6 +1020,7 @@ static struct elevator_type kyber_sched = {
 		.completed_request = kyber_completed_request,
 		.dispatch_request = kyber_dispatch_request,
 		.has_work = kyber_has_work,
+		.depth_updated = kyber_depth_updated,
 	},
 #ifdef CONFIG_BLK_DEBUG_FS
 	.queue_debugfs_attrs = kyber_queue_debugfs_attrs,
diff --git a/block/mq-deadline.c b/block/mq-deadline.c
index b57470e154c8..f3631a287466 100644
--- a/block/mq-deadline.c
+++ b/block/mq-deadline.c
@@ -18,6 +18,8 @@
 #include <linux/rbtree.h>
 #include <linux/sbitmap.h>
 
+#include <trace/events/block.h>
+
 #include "blk.h"
 #include "blk-mq.h"
 #include "blk-mq-debugfs.h"
@@ -496,7 +498,7 @@ static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
 	if (blk_mq_sched_try_insert_merge(q, rq))
 		return;
 
-	blk_mq_sched_request_inserted(rq);
+	trace_block_rq_insert(rq);
 
 	if (at_head || blk_rq_is_passthrough(rq)) {
 		if (at_head)
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index a06b99473ca0..a370cde3ddd4 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -1212,6 +1212,9 @@ static int __loop_clr_fd(struct loop_device *lo, bool release)
 		goto out_unlock;
 	}
 
+	if (test_bit(QUEUE_FLAG_WC, &lo->lo_queue->queue_flags))
+		blk_queue_write_cache(lo->lo_queue, false, false);
+
 	/* freeze request queue during the transition */
 	blk_mq_freeze_queue(lo->lo_queue);
 
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 8b9622eb0a21..4ff71b579cfc 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -78,8 +78,7 @@ struct link_dead_args {
 #define NBD_RT_HAS_PID_FILE		3
 #define NBD_RT_HAS_CONFIG_REF		4
 #define NBD_RT_BOUND			5
-#define NBD_RT_DESTROY_ON_DISCONNECT	6
-#define NBD_RT_DISCONNECT_ON_CLOSE	7
+#define NBD_RT_DISCONNECT_ON_CLOSE	6
 
 #define NBD_DESTROY_ON_DISCONNECT	0
 #define NBD_DISCONNECT_REQUESTED	1
@@ -1904,12 +1903,21 @@ again:
 	if (info->attrs[NBD_ATTR_CLIENT_FLAGS]) {
 		u64 flags = nla_get_u64(info->attrs[NBD_ATTR_CLIENT_FLAGS]);
 		if (flags & NBD_CFLAG_DESTROY_ON_DISCONNECT) {
-			set_bit(NBD_RT_DESTROY_ON_DISCONNECT,
-				&config->runtime_flags);
-			set_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags);
-			put_dev = true;
+			/*
+			 * We have 1 ref to keep the device around, and then 1
+			 * ref for our current operation here, which will be
+			 * inherited by the config.  If we already have
+			 * DESTROY_ON_DISCONNECT set then we know we don't have
+			 * that extra ref already held so we don't need the
+			 * put_dev.
+			 */
+			if (!test_and_set_bit(NBD_DESTROY_ON_DISCONNECT,
+					      &nbd->flags))
+				put_dev = true;
 		} else {
-			clear_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags);
+			if (test_and_clear_bit(NBD_DESTROY_ON_DISCONNECT,
+					       &nbd->flags))
+				refcount_inc(&nbd->refs);
 		}
 		if (flags & NBD_CFLAG_DISCONNECT_ON_CLOSE) {
 			set_bit(NBD_RT_DISCONNECT_ON_CLOSE,
@@ -2080,15 +2088,13 @@ static int nbd_genl_reconfigure(struct sk_buff *skb, struct genl_info *info)
 	if (info->attrs[NBD_ATTR_CLIENT_FLAGS]) {
 		u64 flags = nla_get_u64(info->attrs[NBD_ATTR_CLIENT_FLAGS]);
 		if (flags & NBD_CFLAG_DESTROY_ON_DISCONNECT) {
-			if (!test_and_set_bit(NBD_RT_DESTROY_ON_DISCONNECT,
-					      &config->runtime_flags))
+			if (!test_and_set_bit(NBD_DESTROY_ON_DISCONNECT,
+					      &nbd->flags))
 				put_dev = true;
-			set_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags);
 		} else {
-			if (test_and_clear_bit(NBD_RT_DESTROY_ON_DISCONNECT,
-					       &config->runtime_flags))
+			if (test_and_clear_bit(NBD_DESTROY_ON_DISCONNECT,
+					       &nbd->flags))
 				refcount_inc(&nbd->refs);
-			clear_bit(NBD_DESTROY_ON_DISCONNECT, &nbd->flags);
 		}
 
 		if (flags & NBD_CFLAG_DISCONNECT_ON_CLOSE) {
diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index da16121140ca..1cdf09ff67b6 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -1326,9 +1326,7 @@ static int dispatch_rw_block_io(struct xen_blkif_ring *ring,
 				     pages[i]->page,
 				     seg[i].nsec << 9,
 				     seg[i].offset) == 0)) {
-
-			int nr_iovecs = min_t(int, (nseg-i), BIO_MAX_PAGES);
-			bio = bio_alloc(GFP_KERNEL, nr_iovecs);
+			bio = bio_alloc(GFP_KERNEL, bio_max_segs(nseg - i));
 			if (unlikely(bio == NULL))
 				goto fail_put_bio;
 
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index 4312007d2d34..2d3cda0acacb 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -341,8 +341,8 @@ static void do_region(int op, int op_flags, unsigned region,
 			num_bvecs = 1;
 			break;
 		default:
-			num_bvecs = min_t(int, BIO_MAX_PAGES,
-					  dm_sector_div_up(remaining, (PAGE_SIZE >> SECTOR_SHIFT)));
+			num_bvecs = bio_max_segs(dm_sector_div_up(remaining,
+						(PAGE_SIZE >> SECTOR_SHIFT)));
 		}
 
 		bio = bio_alloc_bioset(GFP_NOIO, num_bvecs, &io->client->bios);
diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index e3d35c6c9f71..57882654ffee 100644
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -264,15 +264,14 @@ static int write_inline_data(struct log_writes_c *lc, void *entry,
 			     size_t entrylen, void *data, size_t datalen,
 			     sector_t sector)
 {
-	int num_pages, bio_pages, pg_datalen, pg_sectorlen, i;
+	int bio_pages, pg_datalen, pg_sectorlen, i;
 	struct page *page;
 	struct bio *bio;
 	size_t ret;
 	void *ptr;
 
 	while (datalen) {
-		num_pages = ALIGN(datalen, PAGE_SIZE) >> PAGE_SHIFT;
-		bio_pages = min(num_pages, BIO_MAX_PAGES);
+		bio_pages = bio_max_segs(DIV_ROUND_UP(datalen, PAGE_SIZE));
 
 		atomic_inc(&lc->io_blocks);
 
@@ -364,7 +363,7 @@ static int log_one_block(struct log_writes_c *lc,
 		goto out;
 
 	atomic_inc(&lc->io_blocks);
-	bio = bio_alloc(GFP_KERNEL, min(block->vec_cnt, BIO_MAX_PAGES));
+	bio = bio_alloc(GFP_KERNEL, bio_max_segs(block->vec_cnt));
 	if (!bio) {
 		DMERR("Couldn't alloc log bio");
 		goto error;
@@ -386,7 +385,8 @@ static int log_one_block(struct log_writes_c *lc,
 		if (ret != block->vecs[i].bv_len) {
 			atomic_inc(&lc->io_blocks);
 			submit_bio(bio);
-			bio = bio_alloc(GFP_KERNEL, min(block->vec_cnt - i, BIO_MAX_PAGES));
+			bio = bio_alloc(GFP_KERNEL,
+					bio_max_segs(block->vec_cnt - i));
 			if (!bio) {
 				DMERR("Couldn't alloc log bio");
 				goto error;
diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 3d9a5d3ed9cd..9a8b3726a37c 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -185,7 +185,7 @@ static int nvmet_bdev_alloc_bip(struct nvmet_req *req, struct bio *bio,
 	}
 
 	bip = bio_integrity_alloc(bio, GFP_NOIO,
-		min_t(unsigned int, req->metadata_sg_cnt, BIO_MAX_PAGES));
+					bio_max_segs(req->metadata_sg_cnt));
 	if (IS_ERR(bip)) {
 		pr_err("Unable to allocate bio_integrity_payload\n");
 		return PTR_ERR(bip);
@@ -225,7 +225,7 @@ static int nvmet_bdev_alloc_bip(struct nvmet_req *req, struct bio *bio,
 
 static void nvmet_bdev_execute_rw(struct nvmet_req *req)
 {
-	int sg_cnt = req->sg_cnt;
+	unsigned int sg_cnt = req->sg_cnt;
 	struct bio *bio;
 	struct scatterlist *sg;
 	struct blk_plug plug;
@@ -262,7 +262,7 @@ static void nvmet_bdev_execute_rw(struct nvmet_req *req)
 		bio = &req->b.inline_bio;
 		bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
 	} else {
-		bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
+		bio = bio_alloc(GFP_KERNEL, bio_max_segs(sg_cnt));
 	}
 	bio_set_dev(bio, req->ns->bdev);
 	bio->bi_iter.bi_sector = sector;
@@ -289,7 +289,7 @@ static void nvmet_bdev_execute_rw(struct nvmet_req *req)
 				}
 			}
 
-			bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES));
+			bio = bio_alloc(GFP_KERNEL, bio_max_segs(sg_cnt));
 			bio_set_dev(bio, req->ns->bdev);
 			bio->bi_iter.bi_sector = sector;
 			bio->bi_opf = op;
diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c
index f50c7b2bf21c..26c587ccd152 100644
--- a/drivers/nvme/target/passthru.c
+++ b/drivers/nvme/target/passthru.c
@@ -26,7 +26,7 @@ static u16 nvmet_passthru_override_id_ctrl(struct nvmet_req *req)
 	struct nvme_ctrl *pctrl = ctrl->subsys->passthru_ctrl;
 	u16 status = NVME_SC_SUCCESS;
 	struct nvme_id_ctrl *id;
-	int max_hw_sectors;
+	unsigned int max_hw_sectors;
 	int page_shift;
 
 	id = kzalloc(sizeof(*id), GFP_KERNEL);
@@ -198,7 +198,7 @@ static int nvmet_passthru_map_sg(struct nvmet_req *req, struct request *rq)
 		bio = &req->p.inline_bio;
 		bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec));
 	} else {
-		bio = bio_alloc(GFP_KERNEL, min(req->sg_cnt, BIO_MAX_PAGES));
+		bio = bio_alloc(GFP_KERNEL, bio_max_segs(req->sg_cnt));
 		bio->bi_end_io = bio_put;
 	}
 	bio->bi_opf = req_op(rq);
diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 8ed93fd205c7..ee3d52061281 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -315,10 +315,8 @@ iblock_get_bio(struct se_cmd *cmd, sector_t lba, u32 sg_num, int op,
 	 * Only allocate as many vector entries as the bio code allows us to,
 	 * we'll loop later on until we have handled the whole request.
 	 */
-	if (sg_num > BIO_MAX_PAGES)
-		sg_num = BIO_MAX_PAGES;
-
-	bio = bio_alloc_bioset(GFP_NOIO, sg_num, &ib_dev->ibd_bio_set);
+	bio = bio_alloc_bioset(GFP_NOIO, bio_max_segs(sg_num),
+				&ib_dev->ibd_bio_set);
 	if (!bio) {
 		pr_err("Unable to allocate memory for bio\n");
 		return NULL;
@@ -638,8 +636,7 @@ iblock_alloc_bip(struct se_cmd *cmd, struct bio *bio,
 		return -ENODEV;
 	}
 
-	bip = bio_integrity_alloc(bio, GFP_NOIO,
-			min_t(unsigned int, cmd->t_prot_nents, BIO_MAX_PAGES));
+	bip = bio_integrity_alloc(bio, GFP_NOIO, bio_max_segs(cmd->t_prot_nents));
 	if (IS_ERR(bip)) {
 		pr_err("Unable to allocate bio_integrity_payload\n");
 		return PTR_ERR(bip);
diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c
index 33770e5808ce..3cbc074992bc 100644
--- a/drivers/target/target_core_pscsi.c
+++ b/drivers/target/target_core_pscsi.c
@@ -881,7 +881,7 @@ pscsi_map_sg(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents,
 
 			if (!bio) {
 new_bio:
-				nr_vecs = min_t(int, BIO_MAX_PAGES, nr_pages);
+				nr_vecs = bio_max_segs(nr_pages);
 				nr_pages -= nr_vecs;
 				/*
 				 * Calls bio_kmalloc() and sets bio->bi_end_io()
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 91ff9bfd7c1a..4aa1f88d5bf8 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -221,7 +221,7 @@ static void blkdev_bio_end_io_simple(struct bio *bio)
 
 static ssize_t
 __blkdev_direct_IO_simple(struct kiocb *iocb, struct iov_iter *iter,
-		int nr_pages)
+		unsigned int nr_pages)
 {
 	struct file *file = iocb->ki_filp;
 	struct block_device *bdev = I_BDEV(bdev_file_inode(file));
@@ -355,8 +355,8 @@ static void blkdev_bio_end_io(struct bio *bio)
 	}
 }
 
-static ssize_t
-__blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
+static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
+		unsigned int nr_pages)
 {
 	struct file *file = iocb->ki_filp;
 	struct inode *inode = bdev_file_inode(file);
@@ -486,7 +486,7 @@ __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, int nr_pages)
 static ssize_t
 blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 {
-	int nr_pages;
+	unsigned int nr_pages;
 
 	if (!iov_iter_count(iter))
 		return 0;
@@ -495,7 +495,7 @@ blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 	if (is_sync_kiocb(iocb) && nr_pages <= BIO_MAX_PAGES)
 		return __blkdev_direct_IO_simple(iocb, iter, nr_pages);
 
-	return __blkdev_direct_IO(iocb, iter, min(nr_pages, BIO_MAX_PAGES));
+	return __blkdev_direct_IO(iocb, iter, bio_max_segs(nr_pages));
 }
 
 static __init int blkdev_init(void)
diff --git a/fs/direct-io.c b/fs/direct-io.c
index 0957e1bb8eb2..b61491bf3166 100644
--- a/fs/direct-io.c
+++ b/fs/direct-io.c
@@ -695,7 +695,7 @@ static inline int dio_new_bio(struct dio *dio, struct dio_submit *sdio,
 	if (ret)
 		goto out;
 	sector = start_sector << (sdio->blkbits - 9);
-	nr_pages = min(sdio->pages_in_io, BIO_MAX_PAGES);
+	nr_pages = bio_max_segs(sdio->pages_in_io);
 	BUG_ON(nr_pages <= 0);
 	dio_bio_alloc(dio, sdio, map_bh->b_bdev, sector, nr_pages);
 	sdio->boundary = 0;
diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index ea4f693bee22..f88851c5c250 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -215,10 +215,8 @@ submit_bio_retry:
 		/* max # of continuous pages */
 		if (nblocks > DIV_ROUND_UP(map.m_plen, PAGE_SIZE))
 			nblocks = DIV_ROUND_UP(map.m_plen, PAGE_SIZE);
-		if (nblocks > BIO_MAX_PAGES)
-			nblocks = BIO_MAX_PAGES;
 
-		bio = bio_alloc(GFP_NOIO, nblocks);
+		bio = bio_alloc(GFP_NOIO, bio_max_segs(nblocks));
 
 		bio->bi_end_io = erofs_readendio;
 		bio_set_dev(bio, sb->s_bdev);
diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
index f014c5e473a9..3db923403505 100644
--- a/fs/ext4/readpage.c
+++ b/fs/ext4/readpage.c
@@ -371,8 +371,7 @@ int ext4_mpage_readpages(struct inode *inode,
 			 * bio_alloc will _always_ be able to allocate a bio if
 			 * __GFP_DIRECT_RECLAIM is set, see bio_alloc_bioset().
 			 */
-			bio = bio_alloc(GFP_KERNEL,
-				min_t(int, nr_pages, BIO_MAX_PAGES));
+			bio = bio_alloc(GFP_KERNEL, bio_max_segs(nr_pages));
 			fscrypt_set_bio_crypt_ctx(bio, inode, next_block,
 						  GFP_KERNEL);
 			ext4_set_bio_post_read_ctx(bio, inode, page->index);
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index b9721c8f116c..7c95818639a6 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -969,8 +969,7 @@ static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
 	unsigned int post_read_steps = 0;
 
 	bio = bio_alloc_bioset(for_write ? GFP_NOIO : GFP_KERNEL,
-			       min_t(int, nr_pages, BIO_MAX_PAGES),
-			       &f2fs_bioset);
+			       bio_max_segs(nr_pages), &f2fs_bioset);
 	if (!bio)
 		return ERR_PTR(-ENOMEM);
 
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index a8a0fb890e8d..4b0e2e3c2c88 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -2747,7 +2747,7 @@ int f2fs_restore_node_summary(struct f2fs_sb_info *sbi,
 	sum_entry = &sum->entries[0];
 
 	for (i = 0; i < last_offset; i += nrpages, addr += nrpages) {
-		nrpages = min(last_offset - i, BIO_MAX_PAGES);
+		nrpages = bio_max_segs(last_offset - i);
 
 		/* readahead node pages */
 		f2fs_ra_meta_pages(sbi, addr, nrpages, META_POR, true);
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 16a1e82e3aeb..0d9d1a6a947e 100644
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -278,14 +278,14 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data,
 	if (!is_contig || bio_full(ctx->bio, plen)) {
 		gfp_t gfp = mapping_gfp_constraint(page->mapping, GFP_KERNEL);
 		gfp_t orig_gfp = gfp;
-		int nr_vecs = (length + PAGE_SIZE - 1) >> PAGE_SHIFT;
+		unsigned int nr_vecs = DIV_ROUND_UP(length, PAGE_SIZE);
 
 		if (ctx->bio)
 			submit_bio(ctx->bio);
 
 		if (ctx->rac) /* same as readahead_gfp_mask */
 			gfp |= __GFP_NORETRY | __GFP_NOWARN;
-		ctx->bio = bio_alloc(gfp, min(BIO_MAX_PAGES, nr_vecs));
+		ctx->bio = bio_alloc(gfp, bio_max_segs(nr_vecs));
 		/*
 		 * If the bio_alloc fails, try it again for a single page to
 		 * avoid having to deal with partial page reads.  This emulates
diff --git a/fs/mpage.c b/fs/mpage.c
index 830e6cc2a9e7..961234d68779 100644
--- a/fs/mpage.c
+++ b/fs/mpage.c
@@ -304,9 +304,7 @@ alloc_new:
 				goto out;
 		}
 		args->bio = mpage_alloc(bdev, blocks[0] << (blkbits - 9),
-					min_t(int, args->nr_pages,
-					      BIO_MAX_PAGES),
-					gfp);
+					bio_max_segs(args->nr_pages), gfp);
 		if (args->bio == NULL)
 			goto confused;
 	}
diff --git a/fs/nfs/blocklayout/blocklayout.c b/fs/nfs/blocklayout/blocklayout.c
index 1a96ce28efb0..fe860c538747 100644
--- a/fs/nfs/blocklayout/blocklayout.c
+++ b/fs/nfs/blocklayout/blocklayout.c
@@ -115,13 +115,13 @@ bl_submit_bio(struct bio *bio)
 	return NULL;
 }
 
-static struct bio *
-bl_alloc_init_bio(int npg, struct block_device *bdev, sector_t disk_sector,
+static struct bio *bl_alloc_init_bio(unsigned int npg,
+		struct block_device *bdev, sector_t disk_sector,
 		bio_end_io_t end_io, struct parallel_io *par)
 {
 	struct bio *bio;
 
-	npg = min(npg, BIO_MAX_PAGES);
+	npg = bio_max_segs(npg);
 	bio = bio_alloc(GFP_NOIO, npg);
 	if (bio) {
 		bio->bi_iter.bi_sector = disk_sector;
diff --git a/fs/xfs/xfs_bio_io.c b/fs/xfs/xfs_bio_io.c
index e2148f2d5d6b..17f36db2f792 100644
--- a/fs/xfs/xfs_bio_io.c
+++ b/fs/xfs/xfs_bio_io.c
@@ -6,7 +6,7 @@
 
 static inline unsigned int bio_max_vecs(unsigned int count)
 {
-	return min_t(unsigned, howmany(count, PAGE_SIZE), BIO_MAX_PAGES);
+	return bio_max_segs(howmany(count, PAGE_SIZE));
 }
 
 int
diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index f6e5235df7c9..37a1d12762d8 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1480,7 +1480,7 @@ xfs_buf_ioapply_map(
 	int		op)
 {
 	int		page_index;
-	int		total_nr_pages = bp->b_page_count;
+	unsigned int	total_nr_pages = bp->b_page_count;
 	int		nr_pages;
 	struct bio	*bio;
 	sector_t	sector =  bp->b_maps[map].bm_bn;
@@ -1505,7 +1505,7 @@ xfs_buf_ioapply_map(
 
 next_chunk:
 	atomic_inc(&bp->b_io_remaining);
-	nr_pages = min(total_nr_pages, BIO_MAX_PAGES);
+	nr_pages = bio_max_segs(total_nr_pages);
 
 	bio = bio_alloc(GFP_NOIO, nr_pages);
 	bio_set_dev(bio, bp->b_target->bt_bdev);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 5b468f2242ff..983ed2fe7c85 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -20,7 +20,12 @@
 #define BIO_BUG_ON
 #endif
 
-#define BIO_MAX_PAGES		256
+#define BIO_MAX_PAGES		256U
+
+static inline unsigned int bio_max_segs(unsigned int nr_segs)
+{
+	return min(nr_segs, BIO_MAX_PAGES);
+}
 
 #define bio_prio(bio)			(bio)->bi_ioprio
 #define bio_set_prio(bio, prio)		((bio)->bi_ioprio = prio)
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 69035e9f632b..c032cfe133c7 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -462,7 +462,6 @@ struct request_queue {
 #ifdef CONFIG_PM
 	struct device		*dev;
 	enum rpm_status		rpm_status;
-	unsigned int		nr_pending;
 #endif
 
 	/*
diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h
index 05556573b896..a083e15df608 100644
--- a/include/linux/blktrace_api.h
+++ b/include/linux/blktrace_api.h
@@ -23,8 +23,6 @@ struct blk_trace {
 	u32 pid;
 	u32 dev;
 	struct dentry *dir;
-	struct dentry *dropped_file;
-	struct dentry *msg_file;
 	struct list_head running_list;
 	atomic_t dropped;
 };
@@ -119,7 +117,7 @@ struct compat_blk_user_trace_setup {
 
 #endif
 
-extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);
+void blk_fill_rwbs(char *rwbs, unsigned int op);
 
 static inline sector_t blk_rq_trace_sector(struct request *rq)
 {
diff --git a/include/trace/events/bcache.h b/include/trace/events/bcache.h
index e41c611d6d3b..899fdacf57b9 100644
--- a/include/trace/events/bcache.h
+++ b/include/trace/events/bcache.h
@@ -28,7 +28,7 @@ DECLARE_EVENT_CLASS(bcache_request,
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->orig_sector	= bio->bi_iter.bi_sector - 16;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d %s %llu + %u (from %d,%d @ %llu)",
@@ -102,7 +102,7 @@ DECLARE_EVENT_CLASS(bcache_bio,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d  %s %llu + %u",
@@ -137,7 +137,7 @@ TRACE_EVENT(bcache_read,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		__entry->cache_hit = hit;
 		__entry->bypass = bypass;
 	),
@@ -168,7 +168,7 @@ TRACE_EVENT(bcache_write,
 		__entry->inode		= inode;
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		__entry->writeback = writeback;
 		__entry->bypass = bypass;
 	),
@@ -238,7 +238,7 @@ TRACE_EVENT(bcache_journal_write,
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio->bi_iter.bi_size >> 9;
 		__entry->nr_keys	= keys;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d  %s %llu + %u keys %u",
diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index 0d782663a005..cc5ab96a7471 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -89,7 +89,7 @@ TRACE_EVENT(block_rq_requeue,
 		__entry->sector    = blk_rq_trace_sector(rq);
 		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);
 
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 		__get_str(cmd)[0] = '\0';
 	),
 
@@ -133,7 +133,7 @@ TRACE_EVENT(block_rq_complete,
 		__entry->nr_sector = nr_bytes >> 9;
 		__entry->error     = error;
 
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, nr_bytes);
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 		__get_str(cmd)[0] = '\0';
 	),
 
@@ -166,7 +166,7 @@ DECLARE_EVENT_CLASS(block_rq,
 		__entry->nr_sector = blk_rq_trace_nr_sectors(rq);
 		__entry->bytes     = blk_rq_bytes(rq);
 
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 		__get_str(cmd)[0] = '\0';
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
@@ -196,7 +196,7 @@ DEFINE_EVENT(block_rq, block_rq_insert,
 
 /**
  * block_rq_issue - issue pending block IO request operation to device driver
- * @rq: block IO operation operation request
+ * @rq: block IO operation request
  *
  * Called when block operation request @rq from queue @q is sent to a
  * device driver for processing.
@@ -210,7 +210,7 @@ DEFINE_EVENT(block_rq, block_rq_issue,
 
 /**
  * block_rq_merge - merge request with another one in the elevator
- * @rq: block IO operation operation request
+ * @rq: block IO operation request
  *
  * Called when block operation request @rq from queue @q is merged to another
  * request queued in the elevator.
@@ -249,7 +249,7 @@ TRACE_EVENT(block_bio_complete,
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio_sectors(bio);
 		__entry->error		= blk_status_to_errno(bio->bi_status);
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d %s %llu + %u [%d]",
@@ -276,7 +276,7 @@ DECLARE_EVENT_CLASS(block_bio,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->nr_sector	= bio_sectors(bio);
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
 
@@ -433,7 +433,7 @@ TRACE_EVENT(block_split,
 		__entry->dev		= bio_dev(bio);
 		__entry->sector		= bio->bi_iter.bi_sector;
 		__entry->new_sector	= new_sector;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
 	),
 
@@ -474,7 +474,7 @@ TRACE_EVENT(block_bio_remap,
 		__entry->nr_sector	= bio_sectors(bio);
 		__entry->old_dev	= dev;
 		__entry->old_sector	= from;
-		blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
+		blk_fill_rwbs(__entry->rwbs, bio->bi_opf);
 	),
 
 	TP_printk("%d,%d %s %llu + %u <- (%d,%d) %llu",
@@ -518,7 +518,7 @@ TRACE_EVENT(block_rq_remap,
 		__entry->old_dev	= dev;
 		__entry->old_sector	= from;
 		__entry->nr_bios	= blk_rq_count_bios(rq);
-		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, blk_rq_bytes(rq));
+		blk_fill_rwbs(__entry->rwbs, rq->cmd_flags);
 	),
 
 	TP_printk("%d,%d %s %llu + %u <- (%d,%d) %llu %u",
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index c286c13bd31a..c221e4c3f625 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -312,8 +312,6 @@ record_it:
 
 static void blk_trace_free(struct blk_trace *bt)
 {
-	debugfs_remove(bt->msg_file);
-	debugfs_remove(bt->dropped_file);
 	relay_close(bt->rchan);
 	debugfs_remove(bt->dir);
 	free_percpu(bt->sequence);
@@ -545,10 +543,8 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 	INIT_LIST_HEAD(&bt->running_list);
 
 	ret = -EIO;
-	bt->dropped_file = debugfs_create_file("dropped", 0444, dir, bt,
-					       &blk_dropped_fops);
-
-	bt->msg_file = debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops);
+	debugfs_create_file("dropped", 0444, dir, bt, &blk_dropped_fops);
+	debugfs_create_file("msg", 0222, dir, bt, &blk_msg_fops);
 
 	bt->rchan = relay_open("trace", dir, buts->buf_size,
 				buts->buf_nr, &blk_relay_callbacks, bt);
@@ -1868,7 +1864,17 @@ void blk_trace_remove_sysfs(struct device *dev)
 
 #ifdef CONFIG_EVENT_TRACING
 
-void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes)
+/**
+ * blk_fill_rwbs - Fill the buffer rwbs by mapping op to character string.
+ * @rwbs:	buffer to be filled
+ * @op:		REQ_OP_XXX for the tracepoint
+ *
+ * Description:
+ *     Maps the REQ_OP_XXX to character and fills the buffer provided by the
+ *     caller with resulting string.
+ *
+ **/
+void blk_fill_rwbs(char *rwbs, unsigned int op)
 {
 	int i = 0;