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