Merge tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block

Pull block updates from Jens Axboe:
"Another series of killing more code than what is being added, again
thanks to Christoph's relentless cleanups and tech debt tackling.

This contains:

- blk-iocost improvements (Baolin Wang)

- part0 iostat fix (Jeffle Xu)

- Disable iopoll for split bios (Jeffle Xu)

- block tracepoint cleanups (Christoph Hellwig)

- Merging of struct block_device and hd_struct (Christoph Hellwig)

- Rework/cleanup of how block device sizes are updated (Christoph
Hellwig)

- Simplification of gendisk lookup and removal of block device
aliasing (Christoph Hellwig)

- Block device ioctl cleanups (Christoph Hellwig)

- Removal of bdget()/blkdev_get() as exported API (Christoph Hellwig)

- Disk change rework, avoid ->revalidate_disk() (Christoph Hellwig)

- sbitmap improvements (Pavel Begunkov)

- Hybrid polling fix (Pavel Begunkov)

- bvec iteration improvements (Pavel Begunkov)

- Zone revalidation fixes (Damien Le Moal)

- blk-throttle limit fix (Yu Kuai)

- Various little fixes"

* tag 'for-5.11/block-2020-12-14' of git://git.kernel.dk/linux-block: (126 commits)
blk-mq: fix msec comment from micro to milli seconds
blk-mq: update arg in comment of blk_mq_map_queue
blk-mq: add helper allocating tagset->tags
Revert "block: Fix a lockdep complaint triggered by request queue flushing"
nvme-loop: use blk_mq_hctx_set_fq_lock_class to set loop's lock class
blk-mq: add new API of blk_mq_hctx_set_fq_lock_class
block: disable iopoll for split bio
block: Improve blk_revalidate_disk_zones() checks
sbitmap: simplify wrap check
sbitmap: replace CAS with atomic and
sbitmap: remove swap_lock
sbitmap: optimise sbitmap_deferred_clear()
blk-mq: skip hybrid polling if iopoll doesn't spin
blk-iocost: Factor out the base vrate change into a separate function
blk-iocost: Factor out the active iocgs' state check into a separate function
blk-iocost: Move the usage ratio calculation to the correct place
blk-iocost: Remove unnecessary advance declaration
blk-iocost: Fix some typos in comments
blktrace: fix up a kerneldoc comment
block: remove the request_queue to argument request based tracepoints
...

block/bio.c

···
 void guard_bio_eod(struct bio *bio)
 {
 	sector_t maxsector;
-	struct hd_struct *part;
+	struct block_device *part;
 
 	rcu_read_lock();
 	part = __disk_get_part(bio->bi_disk, bio->bi_partno);
 	if (part)
-		maxsector = part_nr_sects_read(part);
-	else
+		maxsector = bdev_nr_sectors(part);
+	else	
 		maxsector = get_capacity(bio->bi_disk);
 	rcu_read_unlock();
 
···
 
 		flush_dcache_page(dst_bv.bv_page);
 
-		bio_advance_iter(src, src_iter, bytes);
-		bio_advance_iter(dst, dst_iter, bytes);
+		bio_advance_iter_single(src, src_iter, bytes);
+		bio_advance_iter_single(dst, dst_iter, bytes);
 	}
 }
 EXPORT_SYMBOL(bio_copy_data_iter);

block/blk-cgroup.c

···
 }
 
 /**
- * blkg_conf_prep - parse and prepare for per-blkg config update
+ * blkcg_conf_open_bdev - parse and open bdev for per-blkg config update
  * @inputp: input string pointer
  *
  * Parse the device node prefix part, MAJ:MIN, of per-blkg config update
- * from @input and get and return the matching gendisk.  *@inputp is
+ * from @input and get and return the matching bdev.  *@inputp is
  * updated to point past the device node prefix.  Returns an ERR_PTR()
  * value on error.
  *
  * Use this function iff blkg_conf_prep() can't be used for some reason.
  */
-struct gendisk *blkcg_conf_get_disk(char **inputp)
+struct block_device *blkcg_conf_open_bdev(char **inputp)
 {
 	char *input = *inputp;
 	unsigned int major, minor;
-	struct gendisk *disk;
-	int key_len, part;
+	struct block_device *bdev;
+	int key_len;
 
 	if (sscanf(input, "%u:%u%n", &major, &minor, &key_len) != 2)
 		return ERR_PTR(-EINVAL);
···
 		return ERR_PTR(-EINVAL);
 	input = skip_spaces(input);
 
-	disk = get_gendisk(MKDEV(major, minor), &part);
-	if (!disk)
+	bdev = blkdev_get_no_open(MKDEV(major, minor));
+	if (!bdev)
 		return ERR_PTR(-ENODEV);
-	if (part) {
-		put_disk_and_module(disk);
+	if (bdev_is_partition(bdev)) {
+		blkdev_put_no_open(bdev);
 		return ERR_PTR(-ENODEV);
 	}
 
 	*inputp = input;
-	return disk;
+	return bdev;
 }
 
 /**
···
  */
 int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
 		   char *input, struct blkg_conf_ctx *ctx)
-	__acquires(rcu) __acquires(&disk->queue->queue_lock)
+	__acquires(rcu) __acquires(&bdev->bd_disk->queue->queue_lock)
 {
-	struct gendisk *disk;
+	struct block_device *bdev;
 	struct request_queue *q;
 	struct blkcg_gq *blkg;
 	int ret;
 
-	disk = blkcg_conf_get_disk(&input);
-	if (IS_ERR(disk))
-		return PTR_ERR(disk);
+	bdev = blkcg_conf_open_bdev(&input);
+	if (IS_ERR(bdev))
+		return PTR_ERR(bdev);
 
-	q = disk->queue;
+	q = bdev->bd_disk->queue;
 
 	rcu_read_lock();
 	spin_lock_irq(&q->queue_lock);
···
 			goto success;
 	}
 success:
-	ctx->disk = disk;
+	ctx->bdev = bdev;
 	ctx->blkg = blkg;
 	ctx->body = input;
 	return 0;
···
 	spin_unlock_irq(&q->queue_lock);
 	rcu_read_unlock();
 fail:
-	put_disk_and_module(disk);
+	blkdev_put_no_open(bdev);
 	/*
 	 * If queue was bypassing, we should retry.  Do so after a
 	 * short msleep().  It isn't strictly necessary but queue
···
  * with blkg_conf_prep().
  */
 void blkg_conf_finish(struct blkg_conf_ctx *ctx)
-	__releases(&ctx->disk->queue->queue_lock) __releases(rcu)
+	__releases(&ctx->bdev->bd_disk->queue->queue_lock) __releases(rcu)
 {
-	spin_unlock_irq(&ctx->disk->queue->queue_lock);
+	spin_unlock_irq(&ctx->bdev->bd_disk->queue->queue_lock);
 	rcu_read_unlock();
-	put_disk_and_module(ctx->disk);
+	blkdev_put_no_open(ctx->bdev);
 }
 EXPORT_SYMBOL_GPL(blkg_conf_finish);
 
···
 
 	class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
 	while ((dev = class_dev_iter_next(&iter))) {
-		struct gendisk *disk = dev_to_disk(dev);
-		struct hd_struct *part = disk_get_part(disk, 0);
-		struct blkcg_gq *blkg = blk_queue_root_blkg(disk->queue);
+		struct block_device *bdev = dev_to_bdev(dev);
+		struct blkcg_gq *blkg =
+			blk_queue_root_blkg(bdev->bd_disk->queue);
 		struct blkg_iostat tmp;
 		int cpu;
 
···
 		for_each_possible_cpu(cpu) {
 			struct disk_stats *cpu_dkstats;
 
-			cpu_dkstats = per_cpu_ptr(part->dkstats, cpu);
+			cpu_dkstats = per_cpu_ptr(bdev->bd_stats, cpu);
 			tmp.ios[BLKG_IOSTAT_READ] +=
 				cpu_dkstats->ios[STAT_READ];
 			tmp.ios[BLKG_IOSTAT_WRITE] +=
···
 			blkg_iostat_set(&blkg->iostat.cur, &tmp);
 			u64_stats_update_end(&blkg->iostat.sync);
 		}
-		disk_put_part(part);
 	}
 }
 

block/blk-core.c

···
 }
 __setup("fail_make_request=", setup_fail_make_request);
 
-static bool should_fail_request(struct hd_struct *part, unsigned int bytes)
+static bool should_fail_request(struct block_device *part, unsigned int bytes)
 {
-	return part->make_it_fail && should_fail(&fail_make_request, bytes);
+	return part->bd_make_it_fail && should_fail(&fail_make_request, bytes);
 }
 
 static int __init fail_make_request_debugfs(void)
···
 
 #else /* CONFIG_FAIL_MAKE_REQUEST */
 
-static inline bool should_fail_request(struct hd_struct *part,
+static inline bool should_fail_request(struct block_device *part,
 					unsigned int bytes)
 {
 	return false;
···
 
 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 
-static inline bool bio_check_ro(struct bio *bio, struct hd_struct *part)
+static inline bool bio_check_ro(struct bio *bio, struct block_device *part)
 {
 	const int op = bio_op(bio);
 
-	if (part->policy && op_is_write(op)) {
+	if (part->bd_read_only && op_is_write(op)) {
 		char b[BDEVNAME_SIZE];
 
 		if (op_is_flush(bio->bi_opf) && !bio_sectors(bio))
···
 
 		WARN_ONCE(1,
 		       "Trying to write to read-only block-device %s (partno %d)\n",
-			bio_devname(bio, b), part->partno);
+			bio_devname(bio, b), part->bd_partno);
 		/* Older lvm-tools actually trigger this */
 		return false;
 	}
···
 
 static noinline int should_fail_bio(struct bio *bio)
 {
-	if (should_fail_request(&bio->bi_disk->part0, bio->bi_iter.bi_size))
+	if (should_fail_request(bio->bi_disk->part0, bio->bi_iter.bi_size))
 		return -EIO;
 	return 0;
 }
···
  */
 static inline int blk_partition_remap(struct bio *bio)
 {
-	struct hd_struct *p;
+	struct block_device *p;
 	int ret = -EIO;
 
 	rcu_read_lock();
···
 		goto out;
 
 	if (bio_sectors(bio)) {
-		if (bio_check_eod(bio, part_nr_sects_read(p)))
+		if (bio_check_eod(bio, bdev_nr_sectors(p)))
 			goto out;
-		bio->bi_iter.bi_sector += p->start_sect;
-		trace_block_bio_remap(bio->bi_disk->queue, bio, part_devt(p),
-				      bio->bi_iter.bi_sector - p->start_sect);
+		bio->bi_iter.bi_sector += p->bd_start_sect;
+		trace_block_bio_remap(bio, p->bd_dev,
+				      bio->bi_iter.bi_sector -
+				      p->bd_start_sect);
 	}
 	bio->bi_partno = 0;
 	ret = 0;
···
 		if (unlikely(blk_partition_remap(bio)))
 			goto end_io;
 	} else {
-		if (unlikely(bio_check_ro(bio, &bio->bi_disk->part0)))
+		if (unlikely(bio_check_ro(bio, bio->bi_disk->part0)))
 			goto end_io;
 		if (unlikely(bio_check_eod(bio, get_capacity(bio->bi_disk))))
 			goto end_io;
···
 	blkcg_bio_issue_init(bio);
 
 	if (!bio_flagged(bio, BIO_TRACE_COMPLETION)) {
-		trace_block_bio_queue(q, bio);
+		trace_block_bio_queue(bio);
 		/* Now that enqueuing has been traced, we need to trace
 		 * completion as well.
 		 */
···
 		return ret;
 
 	if (rq->rq_disk &&
-	    should_fail_request(&rq->rq_disk->part0, blk_rq_bytes(rq)))
+	    should_fail_request(rq->rq_disk->part0, blk_rq_bytes(rq)))
 		return BLK_STS_IOERR;
 
 	if (blk_crypto_insert_cloned_request(rq))
···
 }
 EXPORT_SYMBOL_GPL(blk_rq_err_bytes);
 
-static void update_io_ticks(struct hd_struct *part, unsigned long now, bool end)
+static void update_io_ticks(struct block_device *part, unsigned long now,
+		bool end)
 {
 	unsigned long stamp;
 again:
-	stamp = READ_ONCE(part->stamp);
+	stamp = READ_ONCE(part->bd_stamp);
 	if (unlikely(stamp != now)) {
-		if (likely(cmpxchg(&part->stamp, stamp, now) == stamp))
+		if (likely(cmpxchg(&part->bd_stamp, stamp, now) == stamp))
 			__part_stat_add(part, io_ticks, end ? now - stamp : 1);
 	}
-	if (part->partno) {
-		part = &part_to_disk(part)->part0;
+	if (part->bd_partno) {
+		part = bdev_whole(part);
 		goto again;
 	}
 }
···
 {
 	if (req->part && blk_do_io_stat(req)) {
 		const int sgrp = op_stat_group(req_op(req));
-		struct hd_struct *part;
 
 		part_stat_lock();
-		part = req->part;
-		part_stat_add(part, sectors[sgrp], bytes >> 9);
+		part_stat_add(req->part, sectors[sgrp], bytes >> 9);
 		part_stat_unlock();
 	}
 }
···
 	if (req->part && blk_do_io_stat(req) &&
 	    !(req->rq_flags & RQF_FLUSH_SEQ)) {
 		const int sgrp = op_stat_group(req_op(req));
-		struct hd_struct *part;
 
 		part_stat_lock();
-		part = req->part;
-
-		update_io_ticks(part, jiffies, true);
-		part_stat_inc(part, ios[sgrp]);
-		part_stat_add(part, nsecs[sgrp], now - req->start_time_ns);
+		update_io_ticks(req->part, jiffies, true);
+		part_stat_inc(req->part, ios[sgrp]);
+		part_stat_add(req->part, nsecs[sgrp], now - req->start_time_ns);
 		part_stat_unlock();
-
-		hd_struct_put(part);
 	}
 }
 
···
 	part_stat_unlock();
 }
 
-static unsigned long __part_start_io_acct(struct hd_struct *part,
+static unsigned long __part_start_io_acct(struct block_device *part,
 					  unsigned int sectors, unsigned int op)
 {
 	const int sgrp = op_stat_group(op);
···
 	return now;
 }
 
-unsigned long part_start_io_acct(struct gendisk *disk, struct hd_struct **part,
+unsigned long part_start_io_acct(struct gendisk *disk, struct block_device **part,
 				 struct bio *bio)
 {
 	*part = disk_map_sector_rcu(disk, bio->bi_iter.bi_sector);
···
 unsigned long disk_start_io_acct(struct gendisk *disk, unsigned int sectors,
 				 unsigned int op)
 {
-	return __part_start_io_acct(&disk->part0, sectors, op);
+	return __part_start_io_acct(disk->part0, sectors, op);
 }
 EXPORT_SYMBOL(disk_start_io_acct);
 
-static void __part_end_io_acct(struct hd_struct *part, unsigned int op,
+static void __part_end_io_acct(struct block_device *part, unsigned int op,
 			       unsigned long start_time)
 {
 	const int sgrp = op_stat_group(op);
···
 	part_stat_unlock();
 }
 
-void part_end_io_acct(struct hd_struct *part, struct bio *bio,
+void part_end_io_acct(struct block_device *part, struct bio *bio,
 		      unsigned long start_time)
 {
 	__part_end_io_acct(part, bio_op(bio), start_time);
-	hd_struct_put(part);
 }
 EXPORT_SYMBOL_GPL(part_end_io_acct);
 
 void disk_end_io_acct(struct gendisk *disk, unsigned int op,
 		      unsigned long start_time)
 {
-	__part_end_io_acct(&disk->part0, op, start_time);
+	__part_end_io_acct(disk->part0, op, start_time);
 }
 EXPORT_SYMBOL(disk_end_io_acct);
 

block/blk-flush.c

···
 #include <linux/blkdev.h>
 #include <linux/gfp.h>
 #include <linux/blk-mq.h>
-#include <linux/lockdep.h>
 
 #include "blk.h"
 #include "blk-mq.h"
···
 
 static void blk_account_io_flush(struct request *rq)
 {
-	struct hd_struct *part = &rq->rq_disk->part0;
+	struct block_device *part = rq->rq_disk->part0;
 
 	part_stat_lock();
 	part_stat_inc(part, ios[STAT_FLUSH]);
···
 	INIT_LIST_HEAD(&fq->flush_queue[1]);
 	INIT_LIST_HEAD(&fq->flush_data_in_flight);
 
-	lockdep_register_key(&fq->key);
-	lockdep_set_class(&fq->mq_flush_lock, &fq->key);
-
 	return fq;
 
  fail_rq:
···
 	if (!fq)
 		return;
 
-	lockdep_unregister_key(&fq->key);
 	kfree(fq->flush_rq);
 	kfree(fq);
 }
+
+/*
+ * Allow driver to set its own lock class to fq->mq_flush_lock for
+ * avoiding lockdep complaint.
+ *
+ * flush_end_io() may be called recursively from some driver, such as
+ * nvme-loop, so lockdep may complain 'possible recursive locking' because
+ * all 'struct blk_flush_queue' instance share same mq_flush_lock lock class
+ * key. We need to assign different lock class for these driver's
+ * fq->mq_flush_lock for avoiding the lockdep warning.
+ *
+ * Use dynamically allocated lock class key for each 'blk_flush_queue'
+ * instance is over-kill, and more worse it introduces horrible boot delay
+ * issue because synchronize_rcu() is implied in lockdep_unregister_key which
+ * is called for each hctx release. SCSI probing may synchronously create and
+ * destroy lots of MQ request_queues for non-existent devices, and some robot
+ * test kernel always enable lockdep option. It is observed that more than half
+ * an hour is taken during SCSI MQ probe with per-fq lock class.
+ */
+void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx,
+		struct lock_class_key *key)
+{
+	lockdep_set_class(&hctx->fq->mq_flush_lock, key);
+}
+EXPORT_SYMBOL_GPL(blk_mq_hctx_set_fq_lock_class);

block/blk-iocost.c

···
  * On top of that, a size cost proportional to the length of the IO is
  * added.  While simple, this model captures the operational
  * characteristics of a wide varienty of devices well enough.  Default
- * paramters for several different classes of devices are provided and the
+ * parameters for several different classes of devices are provided and the
  * parameters can be configured from userspace via
  * /sys/fs/cgroup/io.cost.model.
  *
···
  *
  * This constitutes the basis of IO capacity distribution.  Each cgroup's
  * vtime is running at a rate determined by its hweight.  A cgroup tracks
- * the vtime consumed by past IOs and can issue a new IO iff doing so
+ * the vtime consumed by past IOs and can issue a new IO if doing so
  * wouldn't outrun the current device vtime.  Otherwise, the IO is
  * suspended until the vtime has progressed enough to cover it.
  *
···
  * Instead of debugfs or other clumsy monitoring mechanisms, this
  * controller uses a drgn based monitoring script -
  * tools/cgroup/iocost_monitor.py.  For details on drgn, please see
- * https://github.com/osandov/drgn.  The ouput looks like the following.
+ * https://github.com/osandov/drgn.  The output looks like the following.
  *
  *  sdb RUN   per=300ms cur_per=234.218:v203.695 busy= +1 vrate= 62.12%
  *                 active      weight      hweight% inflt% dbt  delay usages%
···
 	AUTOP_SSD_FAST,
 };
 
-struct ioc_gq;
-
 struct ioc_params {
 	u32				qos[NR_QOS_PARAMS];
 	u64				i_lcoefs[NR_I_LCOEFS];
···
 	/*
 	 * `vtime` is this iocg's vtime cursor which progresses as IOs are
 	 * issued.  If lagging behind device vtime, the delta represents
-	 * the currently available IO budget.  If runnning ahead, the
+	 * the currently available IO budget.  If running ahead, the
 	 * overage.
 	 *
 	 * `vtime_done` is the same but progressed on completion rather
···
 	ioc->vtime_err = clamp(ioc->vtime_err, -vperiod, vperiod);
 }
 
+static void ioc_adjust_base_vrate(struct ioc *ioc, u32 rq_wait_pct,
+				  int nr_lagging, int nr_shortages,
+				  int prev_busy_level, u32 *missed_ppm)
+{
+	u64 vrate = ioc->vtime_base_rate;
+	u64 vrate_min = ioc->vrate_min, vrate_max = ioc->vrate_max;
+
+	if (!ioc->busy_level || (ioc->busy_level < 0 && nr_lagging)) {
+		if (ioc->busy_level != prev_busy_level || nr_lagging)
+			trace_iocost_ioc_vrate_adj(ioc, atomic64_read(&ioc->vtime_rate),
+						   missed_ppm, rq_wait_pct,
+						   nr_lagging, nr_shortages);
+
+		return;
+	}
+
+	/* rq_wait signal is always reliable, ignore user vrate_min */
+	if (rq_wait_pct > RQ_WAIT_BUSY_PCT)
+		vrate_min = VRATE_MIN;
+
+	/*
+	 * If vrate is out of bounds, apply clamp gradually as the
+	 * bounds can change abruptly.  Otherwise, apply busy_level
+	 * based adjustment.
+	 */
+	if (vrate < vrate_min) {
+		vrate = div64_u64(vrate * (100 + VRATE_CLAMP_ADJ_PCT), 100);
+		vrate = min(vrate, vrate_min);
+	} else if (vrate > vrate_max) {
+		vrate = div64_u64(vrate * (100 - VRATE_CLAMP_ADJ_PCT), 100);
+		vrate = max(vrate, vrate_max);
+	} else {
+		int idx = min_t(int, abs(ioc->busy_level),
+				ARRAY_SIZE(vrate_adj_pct) - 1);
+		u32 adj_pct = vrate_adj_pct[idx];
+
+		if (ioc->busy_level > 0)
+			adj_pct = 100 - adj_pct;
+		else
+			adj_pct = 100 + adj_pct;
+
+		vrate = clamp(DIV64_U64_ROUND_UP(vrate * adj_pct, 100),
+			      vrate_min, vrate_max);
+	}
+
+	trace_iocost_ioc_vrate_adj(ioc, vrate, missed_ppm, rq_wait_pct,
+				   nr_lagging, nr_shortages);
+
+	ioc->vtime_base_rate = vrate;
+	ioc_refresh_margins(ioc);
+}
+
 /* take a snapshot of the current [v]time and vrate */
 static void ioc_now(struct ioc *ioc, struct ioc_now *now)
 {
···
 
 		/*
 		 * The delta between inuse and active sums indicates that
-		 * that much of weight is being given away.  Parent's inuse
+		 * much of weight is being given away.  Parent's inuse
 		 * and active should reflect the ratio.
 		 */
 		if (parent->child_active_sum) {
···
 	}
 }
 
+/*
+ * Check the active iocgs' state to avoid oversleeping and deactive
+ * idle iocgs.
+ *
+ * Since waiters determine the sleep durations based on the vrate
+ * they saw at the time of sleep, if vrate has increased, some
+ * waiters could be sleeping for too long. Wake up tardy waiters
+ * which should have woken up in the last period and expire idle
+ * iocgs.
+ */
+static int ioc_check_iocgs(struct ioc *ioc, struct ioc_now *now)
+{
+	int nr_debtors = 0;
+	struct ioc_gq *iocg, *tiocg;
+
+	list_for_each_entry_safe(iocg, tiocg, &ioc->active_iocgs, active_list) {
+		if (!waitqueue_active(&iocg->waitq) && !iocg->abs_vdebt &&
+		    !iocg->delay && !iocg_is_idle(iocg))
+			continue;
+
+		spin_lock(&iocg->waitq.lock);
+
+		/* flush wait and indebt stat deltas */
+		if (iocg->wait_since) {
+			iocg->local_stat.wait_us += now->now - iocg->wait_since;
+			iocg->wait_since = now->now;
+		}
+		if (iocg->indebt_since) {
+			iocg->local_stat.indebt_us +=
+				now->now - iocg->indebt_since;
+			iocg->indebt_since = now->now;
+		}
+		if (iocg->indelay_since) {
+			iocg->local_stat.indelay_us +=
+				now->now - iocg->indelay_since;
+			iocg->indelay_since = now->now;
+		}
+
+		if (waitqueue_active(&iocg->waitq) || iocg->abs_vdebt ||
+		    iocg->delay) {
+			/* might be oversleeping vtime / hweight changes, kick */
+			iocg_kick_waitq(iocg, true, now);
+			if (iocg->abs_vdebt || iocg->delay)
+				nr_debtors++;
+		} else if (iocg_is_idle(iocg)) {
+			/* no waiter and idle, deactivate */
+			u64 vtime = atomic64_read(&iocg->vtime);
+			s64 excess;
+
+			/*
+			 * @iocg has been inactive for a full duration and will
+			 * have a high budget. Account anything above target as
+			 * error and throw away. On reactivation, it'll start
+			 * with the target budget.
+			 */
+			excess = now->vnow - vtime - ioc->margins.target;
+			if (excess > 0) {
+				u32 old_hwi;
+
+				current_hweight(iocg, NULL, &old_hwi);
+				ioc->vtime_err -= div64_u64(excess * old_hwi,
+							    WEIGHT_ONE);
+			}
+
+			__propagate_weights(iocg, 0, 0, false, now);
+			list_del_init(&iocg->active_list);
+		}
+
+		spin_unlock(&iocg->waitq.lock);
+	}
+
+	commit_weights(ioc);
+	return nr_debtors;
+}
+
 static void ioc_timer_fn(struct timer_list *timer)
 {
 	struct ioc *ioc = container_of(timer, struct ioc, timer);
 	struct ioc_gq *iocg, *tiocg;
 	struct ioc_now now;
 	LIST_HEAD(surpluses);
-	int nr_debtors = 0, nr_shortages = 0, nr_lagging = 0;
+	int nr_debtors, nr_shortages = 0, nr_lagging = 0;
 	u64 usage_us_sum = 0;
 	u32 ppm_rthr = MILLION - ioc->params.qos[QOS_RPPM];
 	u32 ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM];
···
 		return;
 	}
 
-	/*
-	 * Waiters determine the sleep durations based on the vrate they
-	 * saw at the time of sleep.  If vrate has increased, some waiters
-	 * could be sleeping for too long.  Wake up tardy waiters which
-	 * should have woken up in the last period and expire idle iocgs.
-	 */
-	list_for_each_entry_safe(iocg, tiocg, &ioc->active_iocgs, active_list) {
-		if (!waitqueue_active(&iocg->waitq) && !iocg->abs_vdebt &&
-		    !iocg->delay && !iocg_is_idle(iocg))
-			continue;
-
-		spin_lock(&iocg->waitq.lock);
-
-		/* flush wait and indebt stat deltas */
-		if (iocg->wait_since) {
-			iocg->local_stat.wait_us += now.now - iocg->wait_since;
-			iocg->wait_since = now.now;
-		}
-		if (iocg->indebt_since) {
-			iocg->local_stat.indebt_us +=
-				now.now - iocg->indebt_since;
-			iocg->indebt_since = now.now;
-		}
-		if (iocg->indelay_since) {
-			iocg->local_stat.indelay_us +=
-				now.now - iocg->indelay_since;
-			iocg->indelay_since = now.now;
-		}
-
-		if (waitqueue_active(&iocg->waitq) || iocg->abs_vdebt ||
-		    iocg->delay) {
-			/* might be oversleeping vtime / hweight changes, kick */
-			iocg_kick_waitq(iocg, true, &now);
-			if (iocg->abs_vdebt || iocg->delay)
-				nr_debtors++;
-		} else if (iocg_is_idle(iocg)) {
-			/* no waiter and idle, deactivate */
-			u64 vtime = atomic64_read(&iocg->vtime);
-			s64 excess;
-
-			/*
-			 * @iocg has been inactive for a full duration and will
-			 * have a high budget. Account anything above target as
-			 * error and throw away. On reactivation, it'll start
-			 * with the target budget.
-			 */
-			excess = now.vnow - vtime - ioc->margins.target;
-			if (excess > 0) {
-				u32 old_hwi;
-
-				current_hweight(iocg, NULL, &old_hwi);
-				ioc->vtime_err -= div64_u64(excess * old_hwi,
-							    WEIGHT_ONE);
-			}
-
-			__propagate_weights(iocg, 0, 0, false, &now);
-			list_del_init(&iocg->active_list);
-		}
-
-		spin_unlock(&iocg->waitq.lock);
-	}
-	commit_weights(ioc);
+	nr_debtors = ioc_check_iocgs(ioc, &now);
 
 	/*
 	 * Wait and indebt stat are flushed above and the donation calculation
···
 
 	/* calc usage and see whether some weights need to be moved around */
 	list_for_each_entry(iocg, &ioc->active_iocgs, active_list) {
-		u64 vdone, vtime, usage_us, usage_dur;
-		u32 usage, hw_active, hw_inuse;
+		u64 vdone, vtime, usage_us;
+		u32 hw_active, hw_inuse;
 
 		/*
 		 * Collect unused and wind vtime closer to vnow to prevent
···
 		usage_us = iocg->usage_delta_us;
 		usage_us_sum += usage_us;
 
-		if (vdone != vtime) {
-			u64 inflight_us = DIV64_U64_ROUND_UP(
-				cost_to_abs_cost(vtime - vdone, hw_inuse),
-				ioc->vtime_base_rate);
-			usage_us = max(usage_us, inflight_us);
-		}
-
-		/* convert to hweight based usage ratio */
-		if (time_after64(iocg->activated_at, ioc->period_at))
-			usage_dur = max_t(u64, now.now - iocg->activated_at, 1);
-		else
-			usage_dur = max_t(u64, now.now - ioc->period_at, 1);
-
-		usage = clamp_t(u32,
-				DIV64_U64_ROUND_UP(usage_us * WEIGHT_ONE,
-						   usage_dur),
-				1, WEIGHT_ONE);
-
 		/* see whether there's surplus vtime */
 		WARN_ON_ONCE(!list_empty(&iocg->surplus_list));
 		if (hw_inuse < hw_active ||
 		    (!waitqueue_active(&iocg->waitq) &&
 		     time_before64(vtime, now.vnow - ioc->margins.low))) {
-			u32 hwa, old_hwi, hwm, new_hwi;
+			u32 hwa, old_hwi, hwm, new_hwi, usage;
+			u64 usage_dur;
+
+			if (vdone != vtime) {
+				u64 inflight_us = DIV64_U64_ROUND_UP(
+					cost_to_abs_cost(vtime - vdone, hw_inuse),
+					ioc->vtime_base_rate);
+
+				usage_us = max(usage_us, inflight_us);
+			}
+
+			/* convert to hweight based usage ratio */
+			if (time_after64(iocg->activated_at, ioc->period_at))
+				usage_dur = max_t(u64, now.now - iocg->activated_at, 1);
+			else
+				usage_dur = max_t(u64, now.now - ioc->period_at, 1);
+
+			usage = clamp_t(u32,
+				DIV64_U64_ROUND_UP(usage_us * WEIGHT_ONE,
+						   usage_dur),
+				1, WEIGHT_ONE);
 
 			/*
 			 * Already donating or accumulated enough to start.
···
 
 	ioc->busy_level = clamp(ioc->busy_level, -1000, 1000);
 
-	if (ioc->busy_level > 0 || (ioc->busy_level < 0 && !nr_lagging)) {
-		u64 vrate = ioc->vtime_base_rate;
-		u64 vrate_min = ioc->vrate_min, vrate_max = ioc->vrate_max;
-
-		/* rq_wait signal is always reliable, ignore user vrate_min */
-		if (rq_wait_pct > RQ_WAIT_BUSY_PCT)
-			vrate_min = VRATE_MIN;
-
-		/*
-		 * If vrate is out of bounds, apply clamp gradually as the
-		 * bounds can change abruptly.  Otherwise, apply busy_level
-		 * based adjustment.
-		 */
-		if (vrate < vrate_min) {
-			vrate = div64_u64(vrate * (100 + VRATE_CLAMP_ADJ_PCT),
-					  100);
-			vrate = min(vrate, vrate_min);
-		} else if (vrate > vrate_max) {
-			vrate = div64_u64(vrate * (100 - VRATE_CLAMP_ADJ_PCT),
-					  100);
-			vrate = max(vrate, vrate_max);
-		} else {
-			int idx = min_t(int, abs(ioc->busy_level),
-					ARRAY_SIZE(vrate_adj_pct) - 1);
-			u32 adj_pct = vrate_adj_pct[idx];
-
-			if (ioc->busy_level > 0)
-				adj_pct = 100 - adj_pct;
-			else
-				adj_pct = 100 + adj_pct;
-
-			vrate = clamp(DIV64_U64_ROUND_UP(vrate * adj_pct, 100),
-				      vrate_min, vrate_max);
-		}
-
-		trace_iocost_ioc_vrate_adj(ioc, vrate, missed_ppm, rq_wait_pct,
-					   nr_lagging, nr_shortages);
-
-		ioc->vtime_base_rate = vrate;
-		ioc_refresh_margins(ioc);
-	} else if (ioc->busy_level != prev_busy_level || nr_lagging) {
-		trace_iocost_ioc_vrate_adj(ioc, atomic64_read(&ioc->vtime_rate),
-					   missed_ppm, rq_wait_pct, nr_lagging,
-					   nr_shortages);
-	}
+	ioc_adjust_base_vrate(ioc, rq_wait_pct, nr_lagging, nr_shortages,
+			      prev_busy_level, missed_ppm);
 
 	ioc_refresh_params(ioc, false);
 
···
 		return cost;
 
 	/*
-	 * We only increase inuse during period and do so iff the margin has
+	 * We only increase inuse during period and do so if the margin has
 	 * deteriorated since the previous adjustment.
 	 */
 	if (margin >= iocg->saved_margin || margin >= margins->low ||
···
 static ssize_t ioc_qos_write(struct kernfs_open_file *of, char *input,
 			     size_t nbytes, loff_t off)
 {
-	struct gendisk *disk;
+	struct block_device *bdev;
 	struct ioc *ioc;
 	u32 qos[NR_QOS_PARAMS];
 	bool enable, user;
 	char *p;
 	int ret;
 
-	disk = blkcg_conf_get_disk(&input);
-	if (IS_ERR(disk))
-		return PTR_ERR(disk);
+	bdev = blkcg_conf_open_bdev(&input);
+	if (IS_ERR(bdev))
+		return PTR_ERR(bdev);
 
-	ioc = q_to_ioc(disk->queue);
+	ioc = q_to_ioc(bdev->bd_disk->queue);
 	if (!ioc) {
-		ret = blk_iocost_init(disk->queue);
+		ret = blk_iocost_init(bdev->bd_disk->queue);
 		if (ret)
 			goto err;
-		ioc = q_to_ioc(disk->queue);
+		ioc = q_to_ioc(bdev->bd_disk->queue);
 	}
 
 	spin_lock_irq(&ioc->lock);
···
 	ioc_refresh_params(ioc, true);
 	spin_unlock_irq(&ioc->lock);
 
-	put_disk_and_module(disk);
+	blkdev_put_no_open(bdev);
 	return nbytes;
 einval:
 	ret = -EINVAL;
 err:
-	put_disk_and_module(disk);
+	blkdev_put_no_open(bdev);
 	return ret;
 }
 
···
 static ssize_t ioc_cost_model_write(struct kernfs_open_file *of, char *input,
 				    size_t nbytes, loff_t off)
 {
-	struct gendisk *disk;
+	struct block_device *bdev;
 	struct ioc *ioc;
 	u64 u[NR_I_LCOEFS];
 	bool user;
 	char *p;
 	int ret;
 
-	disk = blkcg_conf_get_disk(&input);
-	if (IS_ERR(disk))
-		return PTR_ERR(disk);
+	bdev = blkcg_conf_open_bdev(&input);
+	if (IS_ERR(bdev))
+		return PTR_ERR(bdev);
 
-	ioc = q_to_ioc(disk->queue);
+	ioc = q_to_ioc(bdev->bd_disk->queue);
 	if (!ioc) {
-		ret = blk_iocost_init(disk->queue);
+		ret = blk_iocost_init(bdev->bd_disk->queue);
 		if (ret)
 			goto err;
-		ioc = q_to_ioc(disk->queue);
+		ioc = q_to_ioc(bdev->bd_disk->queue);
 	}
 
 	spin_lock_irq(&ioc->lock);
···
 	ioc_refresh_params(ioc, true);
 	spin_unlock_irq(&ioc->lock);
 
-	put_disk_and_module(disk);
+	blkdev_put_no_open(bdev);
 	return nbytes;
 
 einval:
 	ret = -EINVAL;
 err:
-	put_disk_and_module(disk);
+	blkdev_put_no_open(bdev);
 	return ret;
 }
 

block/blk-lib.c

···
 
 	/* In case the discard request is in a partition */
 	if (bdev_is_partition(bdev))
-		part_offset = bdev->bd_part->start_sect;
+		part_offset = bdev->bd_start_sect;
 
 	while (nr_sects) {
 		sector_t granularity_aligned_lba, req_sects;

block/blk-merge.c

···
 	return NULL;
 split:
 	*segs = nsegs;
+
+	/*
+	 * Bio splitting may cause subtle trouble such as hang when doing sync
+	 * iopoll in direct IO routine. Given performance gain of iopoll for
+	 * big IO can be trival, disable iopoll when split needed.
+	 */
+	bio->bi_opf &= ~REQ_HIPRI;
+
 	return bio_split(bio, sectors, GFP_NOIO, bs);
 }
 
···
 		split->bi_opf |= REQ_NOMERGE;
 
 		bio_chain(split, *bio);
-		trace_block_split(q, split, (*bio)->bi_iter.bi_sector);
+		trace_block_split(split, (*bio)->bi_iter.bi_sector);
 		submit_bio_noacct(*bio);
 		*bio = split;
 	}
···
 		part_stat_lock();
 		part_stat_inc(req->part, merges[op_stat_group(req_op(req))]);
 		part_stat_unlock();
-
-		hd_struct_put(req->part);
 	}
 }
 
···
 	 */
 	blk_account_io_merge_request(next);
 
-	trace_block_rq_merge(q, next);
+	trace_block_rq_merge(next);
 
 	/*
 	 * ownership of bio passed from next to req, return 'next' for
···
 	if (!ll_back_merge_fn(req, bio, nr_segs))
 		return BIO_MERGE_FAILED;
 
-	trace_block_bio_backmerge(req->q, req, bio);
+	trace_block_bio_backmerge(bio);
 	rq_qos_merge(req->q, req, bio);
 
 	if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
···
 	if (!ll_front_merge_fn(req, bio, nr_segs))
 		return BIO_MERGE_FAILED;
 
-	trace_block_bio_frontmerge(req->q, req, bio);
+	trace_block_bio_frontmerge(bio);
 	rq_qos_merge(req->q, req, bio);
 
 	if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)

block/blk-mq-sched.c

···
 
 void blk_mq_sched_request_inserted(struct request *rq)
 {
-	trace_block_rq_insert(rq->q, rq);
+	trace_block_rq_insert(rq);
 }
 EXPORT_SYMBOL_GPL(blk_mq_sched_request_inserted);
 

block/blk-mq.c

···
 }
 
 struct mq_inflight {
-	struct hd_struct *part;
+	struct block_device *part;
 	unsigned int inflight[2];
 };
 
···
 {
 	struct mq_inflight *mi = priv;
 
-	if (rq->part == mi->part && blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT)
+	if ((!mi->part->bd_partno || rq->part == mi->part) &&
+	    blk_mq_rq_state(rq) == MQ_RQ_IN_FLIGHT)
 		mi->inflight[rq_data_dir(rq)]++;
 
 	return true;
 }
 
-unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part)
+unsigned int blk_mq_in_flight(struct request_queue *q,
+		struct block_device *part)
 {
 	struct mq_inflight mi = { .part = part };
 
···
 	return mi.inflight[0] + mi.inflight[1];
 }
 
-void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
-			 unsigned int inflight[2])
+void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
+		unsigned int inflight[2])
 {
 	struct mq_inflight mi = { .part = part };
 
···
 {
 	struct request_queue *q = rq->q;
 
-	trace_block_rq_issue(q, rq);
+	trace_block_rq_issue(rq);
 
 	if (test_bit(QUEUE_FLAG_STATS, &q->queue_flags)) {
 		rq->io_start_time_ns = ktime_get_ns();
···
 
 	blk_mq_put_driver_tag(rq);
 
-	trace_block_rq_requeue(q, rq);
+	trace_block_rq_requeue(rq);
 	rq_qos_requeue(q, rq);
 
 	if (blk_mq_request_started(rq)) {
···
  * __blk_mq_delay_run_hw_queue - Run (or schedule to run) a hardware queue.
  * @hctx: Pointer to the hardware queue to run.
  * @async: If we want to run the queue asynchronously.
- * @msecs: Microseconds of delay to wait before running the queue.
+ * @msecs: Milliseconds of delay to wait before running the queue.
  *
  * If !@async, try to run the queue now. Else, run the queue asynchronously and
  * with a delay of @msecs.
···
 /**
  * blk_mq_delay_run_hw_queue - Run a hardware queue asynchronously.
  * @hctx: Pointer to the hardware queue to run.
- * @msecs: Microseconds of delay to wait before running the queue.
+ * @msecs: Milliseconds of delay to wait before running the queue.
  *
  * Run a hardware queue asynchronously with a delay of @msecs.
  */
···
 /**
  * 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.
+ * @msecs: Milliseconds of delay to wait before running the queues.
  */
 void blk_mq_delay_run_hw_queues(struct request_queue *q, unsigned long msecs)
 {
···
 
 	lockdep_assert_held(&ctx->lock);
 
-	trace_block_rq_insert(hctx->queue, rq);
+	trace_block_rq_insert(rq);
 
 	if (at_head)
 		list_add(&rq->queuelist, &ctx->rq_lists[type]);
···
 	 */
 	list_for_each_entry(rq, list, queuelist) {
 		BUG_ON(rq->mq_ctx != ctx);
-		trace_block_rq_insert(hctx->queue, rq);
+		trace_block_rq_insert(rq);
 	}
 
 	spin_lock(&ctx->lock);
···
 	unsigned int nr_segs;
 	blk_qc_t cookie;
 	blk_status_t ret;
+	bool hipri;
 
 	blk_queue_bounce(q, &bio);
 	__blk_queue_split(&bio, &nr_segs);
···
 
 	rq_qos_throttle(q, bio);
 
+	hipri = bio->bi_opf & REQ_HIPRI;
+
 	data.cmd_flags = bio->bi_opf;
 	rq = __blk_mq_alloc_request(&data);
 	if (unlikely(!rq)) {
···
 		goto queue_exit;
 	}
 
-	trace_block_getrq(q, bio, bio->bi_opf);
+	trace_block_getrq(bio);
 
 	rq_qos_track(q, rq, bio);
 
···
 		blk_mq_sched_insert_request(rq, false, true, true);
 	}
 
+	if (!hipri)
+		return BLK_QC_T_NONE;
 	return cookie;
 queue_exit:
 	blk_queue_exit(q);
···
 	return 0;
 }
 
+static int blk_mq_alloc_tag_set_tags(struct blk_mq_tag_set *set,
+				int new_nr_hw_queues)
+{
+	return blk_mq_realloc_tag_set_tags(set, 0, new_nr_hw_queues);
+}
+
 /*
  * Alloc a tag set to be associated with one or more request queues.
  * May fail with EINVAL for various error conditions. May adjust the
···
 	if (set->nr_maps == 1 && set->nr_hw_queues > nr_cpu_ids)
 		set->nr_hw_queues = nr_cpu_ids;
 
-	if (blk_mq_realloc_tag_set_tags(set, 0, set->nr_hw_queues) < 0)
+	if (blk_mq_alloc_tag_set_tags(set, set->nr_hw_queues) < 0)
 		return -ENOMEM;
 
 	ret = -ENOMEM;
···
 	 * the state. Like for the other success return cases, the
 	 * caller is responsible for checking if the IO completed. If
 	 * the IO isn't complete, we'll get called again and will go
-	 * straight to the busy poll loop.
+	 * straight to the busy poll loop. If specified not to spin,
+	 * we also should not sleep.
 	 */
-	if (blk_mq_poll_hybrid(q, hctx, cookie))
+	if (spin && blk_mq_poll_hybrid(q, hctx, cookie))
 		return 1;
 
 	hctx->poll_considered++;

block/blk-mq.h

···
  * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
  * @q: request queue
  * @flags: request command flags
- * @cpu: cpu ctx
+ * @ctx: software queue cpu ctx
  */
 static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
 						     unsigned int flags,
···
 	return hctx->nr_ctx && hctx->tags;
 }
 
-unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
-void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
-			 unsigned int inflight[2]);
+unsigned int blk_mq_in_flight(struct request_queue *q,
+		struct block_device *part);
+void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
+		unsigned int inflight[2]);
 
 static inline void blk_mq_put_dispatch_budget(struct request_queue *q)
 {

block/blk-throttle.c

···
 	tg_update_has_rules(tg);
 }
 
+#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
 static void blk_throtl_update_limit_valid(struct throtl_data *td)
 {
 	struct cgroup_subsys_state *pos_css;
···
 
 	td->limit_valid[LIMIT_LOW] = low_valid;
 }
+#else
+static inline void blk_throtl_update_limit_valid(struct throtl_data *td)
+{
+}
+#endif
 
 static void throtl_upgrade_state(struct throtl_data *td);
 static void throtl_pd_offline(struct blkg_policy_data *pd)

block/blk-wbt.c

···
 	rwb->enable_state = WBT_STATE_ON_DEFAULT;
 	rwb->wc = 1;
 	rwb->rq_depth.default_depth = RWB_DEF_DEPTH;
-	wbt_update_limits(rwb);
 
 	/*
 	 * Assign rwb and add the stats callback.

block/blk-zoned.c

···
 	noio_flag = memalloc_noio_save();
 	ret = disk->fops->report_zones(disk, 0, UINT_MAX,
 				       blk_revalidate_zone_cb, &args);
+	if (!ret) {
+		pr_warn("%s: No zones reported\n", disk->disk_name);
+		ret = -ENODEV;
+	}
 	memalloc_noio_restore(noio_flag);
+
+	/*
+	 * If zones where reported, make sure that the entire disk capacity
+	 * has been checked.
+	 */
+	if (ret > 0 && args.sector != get_capacity(disk)) {
+		pr_warn("%s: Missing zones from sector %llu\n",
+			disk->disk_name, args.sector);
+		ret = -ENODEV;
+	}
 
 	/*
 	 * Install the new bitmaps and update nr_zones only once the queue is
···
 	 * referencing the bitmaps).
 	 */
 	blk_mq_freeze_queue(q);
-	if (ret >= 0) {
+	if (ret > 0) {
 		blk_queue_chunk_sectors(q, args.zone_sectors);
 		q->nr_zones = args.nr_zones;
 		swap(q->seq_zones_wlock, args.seq_zones_wlock);

block/blk.h

···
 	struct list_head	flush_data_in_flight;
 	struct request		*flush_rq;
 
-	struct lock_class_key	key;
 	spinlock_t		mq_flush_lock;
 };
 
···
 	__elevator_exit(q, e);
 }
 
-struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
+struct block_device *__disk_get_part(struct gendisk *disk, int partno);
 
 ssize_t part_size_show(struct device *dev, struct device_attribute *attr,
 		char *buf);
···
 static inline void blk_queue_free_zone_bitmaps(struct request_queue *q) {}
 #endif
 
-struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);
+struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector);
 
-int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
+int blk_alloc_devt(struct block_device *part, dev_t *devt);
 void blk_free_devt(dev_t devt);
-void blk_invalidate_devt(dev_t devt);
 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 hd_struct *part);
+void delete_partition(struct block_device *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);
 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);
-int hd_ref_init(struct hd_struct *part);
-
-/* no need to get/put refcount of part0 */
-static inline int hd_struct_try_get(struct hd_struct *part)
-{
-	if (part->partno)
-		return percpu_ref_tryget_live(&part->ref);
-	return 1;
-}
-
-static inline void hd_struct_put(struct hd_struct *part)
-{
-	if (part->partno)
-		percpu_ref_put(&part->ref);
-}
-
-static inline void hd_free_part(struct hd_struct *part)
-{
-	free_percpu(part->dkstats);
-	kfree(part->info);
-	percpu_ref_exit(&part->ref);
-}
-
-/*
- * Any access of part->nr_sects which is not protected by partition
- * bd_mutex or gendisk bdev bd_mutex, should be done using this
- * accessor function.
- *
- * Code written along the lines of i_size_read() and i_size_write().
- * CONFIG_PREEMPTION case optimizes the case of UP kernel with preemption
- * on.
- */
-static inline sector_t part_nr_sects_read(struct hd_struct *part)
-{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
-	sector_t nr_sects;
-	unsigned seq;
-	do {
-		seq = read_seqcount_begin(&part->nr_sects_seq);
-		nr_sects = part->nr_sects;
-	} while (read_seqcount_retry(&part->nr_sects_seq, seq));
-	return nr_sects;
-#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
-	sector_t nr_sects;
-
-	preempt_disable();
-	nr_sects = part->nr_sects;
-	preempt_enable();
-	return nr_sects;
-#else
-	return part->nr_sects;
-#endif
-}
-
-/*
- * Should be called with mutex lock held (typically bd_mutex) of partition
- * to provide mutual exlusion among writers otherwise seqcount might be
- * left in wrong state leaving the readers spinning infinitely.
- */
-static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
-{
-#if BITS_PER_LONG==32 && defined(CONFIG_SMP)
-	preempt_disable();
-	write_seqcount_begin(&part->nr_sects_seq);
-	part->nr_sects = size;
-	write_seqcount_end(&part->nr_sects_seq);
-	preempt_enable();
-#elif BITS_PER_LONG==32 && defined(CONFIG_PREEMPTION)
-	preempt_disable();
-	part->nr_sects = size;
-	preempt_enable();
-#else
-	part->nr_sects = size;
-#endif
-}
 
 int bio_add_hw_page(struct request_queue *q, struct bio *bio,
 		struct page *page, unsigned int len, unsigned int offset,

block/bounce.c

···
 		}
 	}
 
-	trace_block_bio_bounce(q, *bio_orig);
+	trace_block_bio_bounce(*bio_orig);
 
 	bio->bi_flags |= (1 << BIO_BOUNCED);
 

block/genhd.c

···
 #include <linux/seq_file.h>
 #include <linux/slab.h>
 #include <linux/kmod.h>
-#include <linux/kobj_map.h>
 #include <linux/mutex.h>
 #include <linux/idr.h>
 #include <linux/log2.h>
···
 
 #include "blk.h"
 
-static DEFINE_MUTEX(block_class_lock);
 static struct kobject *block_depr;
+
+DECLARE_RWSEM(bdev_lookup_sem);
 
 /* for extended dynamic devt allocation, currently only one major is used */
 #define NR_EXT_DEVT		(1 << MINORBITS)
-
-/* For extended devt allocation.  ext_devt_lock prevents look up
- * results from going away underneath its user.
- */
-static DEFINE_SPINLOCK(ext_devt_lock);
-static DEFINE_IDR(ext_devt_idr);
+static DEFINE_IDA(ext_devt_ida);
 
 static void disk_check_events(struct disk_events *ev,
 			      unsigned int *clearing_ptr);
···
 static void disk_del_events(struct gendisk *disk);
 static void disk_release_events(struct gendisk *disk);
 
+void set_capacity(struct gendisk *disk, sector_t sectors)
+{
+	struct block_device *bdev = disk->part0;
+
+	spin_lock(&bdev->bd_size_lock);
+	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
+	spin_unlock(&bdev->bd_size_lock);
+}
+EXPORT_SYMBOL(set_capacity);
+
 /*
- * Set disk capacity and notify if the size is not currently
- * zero and will not be set to zero
+ * Set disk capacity and notify if the size is not currently zero and will not
+ * be set to zero.  Returns true if a uevent was sent, otherwise false.
  */
-bool set_capacity_revalidate_and_notify(struct gendisk *disk, sector_t size,
-					bool update_bdev)
+bool set_capacity_and_notify(struct gendisk *disk, sector_t size)
 {
 	sector_t capacity = get_capacity(disk);
+	char *envp[] = { "RESIZE=1", NULL };
 
 	set_capacity(disk, size);
-	if (update_bdev)
-		revalidate_disk_size(disk, true);
 
-	if (capacity != size && capacity != 0 && size != 0) {
-		char *envp[] = { "RESIZE=1", NULL };
+	/*
+	 * Only print a message and send a uevent if the gendisk is user visible
+	 * and alive.  This avoids spamming the log and udev when setting the
+	 * initial capacity during probing.
+	 */
+	if (size == capacity ||
+	    (disk->flags & (GENHD_FL_UP | GENHD_FL_HIDDEN)) != GENHD_FL_UP)
+		return false;
 
-		kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
-		return true;
-	}
+	pr_info("%s: detected capacity change from %lld to %lld\n",
+		disk->disk_name, size, capacity);
 
-	return false;
+	/*
+	 * Historically we did not send a uevent for changes to/from an empty
+	 * device.
+	 */
+	if (!capacity || !size)
+		return false;
+	kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
+	return true;
 }
-
-EXPORT_SYMBOL_GPL(set_capacity_revalidate_and_notify);
+EXPORT_SYMBOL_GPL(set_capacity_and_notify);
 
 /*
  * Format the device name of the indicated disk into the supplied buffer and
···
 }
 EXPORT_SYMBOL(bdevname);
 
-static void part_stat_read_all(struct hd_struct *part, struct disk_stats *stat)
+static void part_stat_read_all(struct block_device *part,
+		struct disk_stats *stat)
 {
 	int cpu;
 
 	memset(stat, 0, sizeof(struct disk_stats));
 	for_each_possible_cpu(cpu) {
-		struct disk_stats *ptr = per_cpu_ptr(part->dkstats, cpu);
+		struct disk_stats *ptr = per_cpu_ptr(part->bd_stats, cpu);
 		int group;
 
 		for (group = 0; group < NR_STAT_GROUPS; group++) {
···
 	}
 }
 
-static unsigned int part_in_flight(struct hd_struct *part)
+static unsigned int part_in_flight(struct block_device *part)
 {
 	unsigned int inflight = 0;
 	int cpu;
···
 	return inflight;
 }
 
-static void part_in_flight_rw(struct hd_struct *part, unsigned int inflight[2])
+static void part_in_flight_rw(struct block_device *part,
+		unsigned int inflight[2])
 {
 	int cpu;
 
···
 		inflight[1] = 0;
 }
 
-struct hd_struct *__disk_get_part(struct gendisk *disk, int partno)
+struct block_device *__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
- * @partno: partition number
- *
- * Look for partition @partno from @disk.  If found, increment
- * reference count and return it.
- *
- * CONTEXT:
- * Don't care.
- *
- * RETURNS:
- * Pointer to the found partition on success, NULL if not found.
- */
-struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
-{
-	struct hd_struct *part;
-
-	rcu_read_lock();
-	part = __disk_get_part(disk, partno);
-	if (part)
-		get_device(part_to_dev(part));
-	rcu_read_unlock();
-
-	return part;
 }
 
 /**
···
  * CONTEXT:
  * Don't care.
  */
-struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
+struct block_device *disk_part_iter_next(struct disk_part_iter *piter)
 {
 	struct disk_part_tbl *ptbl;
 	int inc, end;
 
 	/* put the last partition */
-	disk_put_part(piter->part);
-	piter->part = NULL;
+	disk_part_iter_exit(piter);
 
 	/* get part_tbl */
 	rcu_read_lock();
···
 
 	/* iterate to the next partition */
 	for (; piter->idx != end; piter->idx += inc) {
-		struct hd_struct *part;
+		struct block_device *part;
 
 		part = rcu_dereference(ptbl->part[piter->idx]);
 		if (!part)
 			continue;
-		if (!part_nr_sects_read(part) &&
+		if (!bdev_nr_sectors(part) &&
 		    !(piter->flags & DISK_PITER_INCL_EMPTY) &&
 		    !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
 		      piter->idx == 0))
 			continue;
 
-		get_device(part_to_dev(part));
-		piter->part = part;
+		piter->part = bdgrab(part);
+		if (!piter->part)
+			continue;
 		piter->idx += inc;
 		break;
 	}
···
  */
 void disk_part_iter_exit(struct disk_part_iter *piter)
 {
-	disk_put_part(piter->part);
+	if (piter->part)
+		bdput(piter->part);
 	piter->part = NULL;
 }
 EXPORT_SYMBOL_GPL(disk_part_iter_exit);
 
-static inline int sector_in_part(struct hd_struct *part, sector_t sector)
+static inline int sector_in_part(struct block_device *part, sector_t sector)
 {
-	return part->start_sect <= sector &&
-		sector < part->start_sect + part_nr_sects_read(part);
+	return part->bd_start_sect <= sector &&
+		sector < part->bd_start_sect + bdev_nr_sectors(part);
 }
 
 /**
···
  * primarily used for stats accounting.
  *
  * CONTEXT:
- * RCU read locked.  The returned partition pointer is always valid
- * because its refcount is grabbed except for part0, which lifetime
- * is same with the disk.
+ * RCU read locked.
  *
  * 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)
+struct block_device *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
 {
 	struct disk_part_tbl *ptbl;
-	struct hd_struct *part;
+	struct block_device *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))
+	if (part && sector_in_part(part, sector))
 		goto out_unlock;
 
 	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);
 			goto out_unlock;
 		}
 	}
 
-	part = &disk->part0;
+	part = disk->part0;
 out_unlock:
 	rcu_read_unlock();
 	return part;
···
 	struct blk_major_name *next;
 	int major;
 	char name[16];
+	void (*probe)(dev_t devt);
 } *major_names[BLKDEV_MAJOR_HASH_SIZE];
+static DEFINE_MUTEX(major_names_lock);
 
 /* index in the above - for now: assume no multimajor ranges */
 static inline int major_to_index(unsigned major)
···
 {
 	struct blk_major_name *dp;
 
-	mutex_lock(&block_class_lock);
+	mutex_lock(&major_names_lock);
 	for (dp = major_names[major_to_index(offset)]; dp; dp = dp->next)
 		if (dp->major == offset)
 			seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
-	mutex_unlock(&block_class_lock);
+	mutex_unlock(&major_names_lock);
 }
 #endif /* CONFIG_PROC_FS */
 
 /**
- * register_blkdev - register a new block device
+ * __register_blkdev - register a new block device
  *
  * @major: the requested major device number [1..BLKDEV_MAJOR_MAX-1]. If
  *         @major = 0, try to allocate any unused major number.
  * @name: the name of the new block device as a zero terminated string
+ * @probe: allback that is called on access to any minor number of @major
  *
  * The @name must be unique within the system.
  *
···
  *
  * See Documentation/admin-guide/devices.txt for the list of allocated
  * major numbers.
+ *
+ * Use register_blkdev instead for any new code.
  */
-int register_blkdev(unsigned int major, const char *name)
+int __register_blkdev(unsigned int major, const char *name,
+		void (*probe)(dev_t devt))
 {
 	struct blk_major_name **n, *p;
 	int index, ret = 0;
 
-	mutex_lock(&block_class_lock);
+	mutex_lock(&major_names_lock);
 
 	/* temporary */
 	if (major == 0) {
···
 	}
 
 	p->major = major;
+	p->probe = probe;
 	strlcpy(p->name, name, sizeof(p->name));
 	p->next = NULL;
 	index = major_to_index(major);
···
 		kfree(p);
 	}
 out:
-	mutex_unlock(&block_class_lock);
+	mutex_unlock(&major_names_lock);
 	return ret;
 }
-
-EXPORT_SYMBOL(register_blkdev);
+EXPORT_SYMBOL(__register_blkdev);
 
 void unregister_blkdev(unsigned int major, const char *name)
 {
···
 	struct blk_major_name *p = NULL;
 	int index = major_to_index(major);
 
-	mutex_lock(&block_class_lock);
+	mutex_lock(&major_names_lock);
 	for (n = &major_names[index]; *n; n = &(*n)->next)
 		if ((*n)->major == major)
 			break;
···
 		p = *n;
 		*n = p->next;
 	}
-	mutex_unlock(&block_class_lock);
+	mutex_unlock(&major_names_lock);
 	kfree(p);
 }
 
 EXPORT_SYMBOL(unregister_blkdev);
-
-static struct kobj_map *bdev_map;
 
 /**
  * blk_mangle_minor - scatter minor numbers apart
···
 }
 
 /**
- * blk_alloc_devt - allocate a dev_t for a partition
- * @part: partition to allocate dev_t for
+ * blk_alloc_devt - allocate a dev_t for a block device
+ * @bdev: block device to allocate dev_t for
  * @devt: out parameter for resulting dev_t
  *
  * Allocate a dev_t for block device.
···
  * CONTEXT:
  * Might sleep.
  */
-int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
+int blk_alloc_devt(struct block_device *bdev, dev_t *devt)
 {
-	struct gendisk *disk = part_to_disk(part);
+	struct gendisk *disk = bdev->bd_disk;
 	int idx;
 
 	/* in consecutive minor range? */
-	if (part->partno < disk->minors) {
-		*devt = MKDEV(disk->major, disk->first_minor + part->partno);
+	if (bdev->bd_partno < disk->minors) {
+		*devt = MKDEV(disk->major, disk->first_minor + bdev->bd_partno);
 		return 0;
 	}
 
-	/* allocate ext devt */
-	idr_preload(GFP_KERNEL);
-
-	spin_lock_bh(&ext_devt_lock);
-	idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_NOWAIT);
-	spin_unlock_bh(&ext_devt_lock);
-
-	idr_preload_end();
+	idx = ida_alloc_range(&ext_devt_ida, 0, NR_EXT_DEVT, GFP_KERNEL);
 	if (idx < 0)
 		return idx == -ENOSPC ? -EBUSY : idx;
 
···
  */
 void blk_free_devt(dev_t devt)
 {
-	if (devt == MKDEV(0, 0))
-		return;
-
-	if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
-		spin_lock_bh(&ext_devt_lock);
-		idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
-		spin_unlock_bh(&ext_devt_lock);
-	}
-}
-
-/*
- * We invalidate devt by assigning NULL pointer for devt in idr.
- */
-void blk_invalidate_devt(dev_t devt)
-{
-	if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
-		spin_lock_bh(&ext_devt_lock);
-		idr_replace(&ext_devt_idr, NULL, blk_mangle_minor(MINOR(devt)));
-		spin_unlock_bh(&ext_devt_lock);
-	}
+	if (MAJOR(devt) == BLOCK_EXT_MAJOR)
+		ida_free(&ext_devt_ida, blk_mangle_minor(MINOR(devt)));
 }
 
 static char *bdevt_str(dev_t devt, char *buf)
···
 		snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
 
 	return buf;
-}
-
-/*
- * Register device numbers dev..(dev+range-1)
- * range must be nonzero
- * The hash chain is sorted on range, so that subranges can override.
- */
-void blk_register_region(dev_t devt, unsigned long range, struct module *module,
-			 struct kobject *(*probe)(dev_t, int *, void *),
-			 int (*lock)(dev_t, void *), void *data)
-{
-	kobj_map(bdev_map, devt, range, module, probe, lock, data);
-}
-
-EXPORT_SYMBOL(blk_register_region);
-
-void blk_unregister_region(dev_t devt, unsigned long range)
-{
-	kobj_unmap(bdev_map, devt, range);
-}
-
-EXPORT_SYMBOL(blk_unregister_region);
-
-static struct kobject *exact_match(dev_t devt, int *partno, void *data)
-{
-	struct gendisk *p = data;
-
-	return &disk_to_dev(p)->kobj;
-}
-
-static int exact_lock(dev_t devt, void *data)
-{
-	struct gendisk *p = data;
-
-	if (!get_disk_and_module(p))
-		return -1;
-	return 0;
 }
 
 static void disk_scan_partitions(struct gendisk *disk)
···
 {
 	struct device *ddev = disk_to_dev(disk);
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 	int err;
 
 	ddev->parent = parent;
···
 	 */
 	pm_runtime_set_memalloc_noio(ddev, true);
 
-	disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
+	disk->part0->bd_holder_dir =
+		kobject_create_and_add("holders", &ddev->kobj);
 	disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
 
 	if (disk->flags & GENHD_FL_HIDDEN) {
···
 	/* announce possible partitions */
 	disk_part_iter_init(&piter, disk, 0);
 	while ((part = disk_part_iter_next(&piter)))
-		kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
+		kobject_uevent(bdev_kobj(part), KOBJ_ADD);
 	disk_part_iter_exit(&piter);
 
 	if (disk->queue->backing_dev_info->dev) {
···
 
 	disk->flags |= GENHD_FL_UP;
 
-	retval = blk_alloc_devt(&disk->part0, &devt);
+	retval = blk_alloc_devt(disk->part0, &devt);
 	if (retval) {
 		WARN_ON(1);
 		return;
···
 		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);
+		bdev_add(disk->part0, devt);
 	}
 	register_disk(parent, disk, groups);
 	if (register_queue)
···
 }
 EXPORT_SYMBOL(device_add_disk_no_queue_reg);
 
-static void invalidate_partition(struct gendisk *disk, int partno)
+static void invalidate_partition(struct block_device *bdev)
 {
-	struct block_device *bdev;
-
-	bdev = bdget_disk(disk, partno);
-	if (!bdev)
-		return;
-
 	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.
+	 * Unhash the bdev inode for this device so that it can't be looked
+	 * up any more even if openers still hold references to it.
 	 */
 	remove_inode_hash(bdev->bd_inode);
-	bdput(bdev);
 }
 
 /**
···
 void del_gendisk(struct gendisk *disk)
 {
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 
 	might_sleep();
+
+	if (WARN_ON_ONCE(!disk->queue))
+		return;
 
 	blk_integrity_del(disk);
 	disk_del_events(disk);
···
 	 * Block lookups of the disk until all bdevs are unhashed and the
 	 * disk is marked as dead (GENHD_FL_UP cleared).
 	 */
-	down_write(&disk->lookup_sem);
+	down_write(&bdev_lookup_sem);
+
 	/* invalidate stuff */
 	disk_part_iter_init(&piter, disk,
 			     DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
 	while ((part = disk_part_iter_next(&piter))) {
-		invalidate_partition(disk, part->partno);
+		invalidate_partition(part);
 		delete_partition(part);
 	}
 	disk_part_iter_exit(&piter);
 
-	invalidate_partition(disk, 0);
+	invalidate_partition(disk->part0);
 	set_capacity(disk, 0);
 	disk->flags &= ~GENHD_FL_UP;
-	up_write(&disk->lookup_sem);
+	up_write(&bdev_lookup_sem);
 
-	if (!(disk->flags & GENHD_FL_HIDDEN))
+	if (!(disk->flags & GENHD_FL_HIDDEN)) {
 		sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
-	if (disk->queue) {
+
 		/*
 		 * Unregister bdi before releasing device numbers (as they can
 		 * get reused and we'd get clashes in sysfs).
 		 */
-		if (!(disk->flags & GENHD_FL_HIDDEN))
-			bdi_unregister(disk->queue->backing_dev_info);
-		blk_unregister_queue(disk);
-	} else {
-		WARN_ON(1);
+		bdi_unregister(disk->queue->backing_dev_info);
 	}
 
-	if (!(disk->flags & GENHD_FL_HIDDEN))
-		blk_unregister_region(disk_devt(disk), disk->minors);
-	/*
-	 * Remove gendisk pointer from idr so that it cannot be looked up
-	 * while RCU period before freeing gendisk is running to prevent
-	 * use-after-free issues. Note that the device number stays
-	 * "in-use" until we really free the gendisk.
-	 */
-	blk_invalidate_devt(disk_devt(disk));
+	blk_unregister_queue(disk);
 
-	kobject_put(disk->part0.holder_dir);
+	kobject_put(disk->part0->bd_holder_dir);
 	kobject_put(disk->slave_dir);
 
-	part_stat_set_all(&disk->part0, 0);
-	disk->part0.stamp = 0;
+	part_stat_set_all(disk->part0, 0);
+	disk->part0->bd_stamp = 0;
 	if (!sysfs_deprecated)
 		sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
 	pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
···
 	return badblocks_store(disk->bb, page, len, 0);
 }
 
-/**
- * get_gendisk - get partitioning information for a given device
- * @devt: device to get partitioning information for
- * @partno: returned partition index
- *
- * This function gets the structure containing partitioning
- * information for the given device @devt.
- *
- * Context: can sleep
- */
-struct gendisk *get_gendisk(dev_t devt, int *partno)
+void blk_request_module(dev_t devt)
 {
-	struct gendisk *disk = NULL;
+	unsigned int major = MAJOR(devt);
+	struct blk_major_name **n;
 
-	might_sleep();
-
-	if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
-		struct kobject *kobj;
-
-		kobj = kobj_lookup(bdev_map, devt, partno);
-		if (kobj)
-			disk = dev_to_disk(kobj_to_dev(kobj));
-	} else {
-		struct hd_struct *part;
-
-		spin_lock_bh(&ext_devt_lock);
-		part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
-		if (part && get_disk_and_module(part_to_disk(part))) {
-			*partno = part->partno;
-			disk = part_to_disk(part);
+	mutex_lock(&major_names_lock);
+	for (n = &major_names[major_to_index(major)]; *n; n = &(*n)->next) {
+		if ((*n)->major == major && (*n)->probe) {
+			(*n)->probe(devt);
+			mutex_unlock(&major_names_lock);
+			return;
 		}
-		spin_unlock_bh(&ext_devt_lock);
 	}
+	mutex_unlock(&major_names_lock);
 
-	if (!disk)
-		return NULL;
-
-	/*
-	 * Synchronize with del_gendisk() to not return disk that is being
-	 * destroyed.
-	 */
-	down_read(&disk->lookup_sem);
-	if (unlikely((disk->flags & GENHD_FL_HIDDEN) ||
-		     !(disk->flags & GENHD_FL_UP))) {
-		up_read(&disk->lookup_sem);
-		put_disk_and_module(disk);
-		disk = NULL;
-	} else {
-		up_read(&disk->lookup_sem);
-	}
-	return disk;
+	if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
+		/* Make old-style 2.4 aliases work */
+		request_module("block-major-%d", MAJOR(devt));
 }
 
 /**
···
  */
 struct block_device *bdget_disk(struct gendisk *disk, int partno)
 {
-	struct hd_struct *part;
 	struct block_device *bdev = NULL;
 
-	part = disk_get_part(disk, partno);
-	if (part)
-		bdev = bdget_part(part);
-	disk_put_part(part);
+	rcu_read_lock();
+	bdev = __disk_get_part(disk, partno);
+	if (bdev && !bdgrab(bdev))
+		bdev = NULL;
+	rcu_read_unlock();
 
 	return bdev;
 }
-EXPORT_SYMBOL(bdget_disk);
 
 /*
  * print a full list of all partitions - intended for places where the root
···
 	while ((dev = class_dev_iter_next(&iter))) {
 		struct gendisk *disk = dev_to_disk(dev);
 		struct disk_part_iter piter;
-		struct hd_struct *part;
+		struct block_device *part;
 		char name_buf[BDEVNAME_SIZE];
 		char devt_buf[BDEVT_SIZE];
 
···
 		 */
 		disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
 		while ((part = disk_part_iter_next(&piter))) {
-			bool is_part0 = part == &disk->part0;
+			bool is_part0 = part == disk->part0;
 
 			printk("%s%s %10llu %s %s", is_part0 ? "" : "  ",
-			       bdevt_str(part_devt(part), devt_buf),
-			       (unsigned long long)part_nr_sects_read(part) >> 1
-			       , disk_name(disk, part->partno, name_buf),
-			       part->info ? part->info->uuid : "");
+			       bdevt_str(part->bd_dev, devt_buf),
+			       bdev_nr_sectors(part) >> 1,
+			       disk_name(disk, part->bd_partno, name_buf),
+			       part->bd_meta_info ?
+					part->bd_meta_info->uuid : "");
 			if (is_part0) {
 				if (dev->parent && dev->parent->driver)
 					printk(" driver: %s\n",
···
 {
 	struct gendisk *sgp = v;
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 	char buf[BDEVNAME_SIZE];
 
 	/* Don't show non-partitionable removeable devices or empty devices */
···
 	disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
 	while ((part = disk_part_iter_next(&piter)))
 		seq_printf(seqf, "%4d  %7d %10llu %s\n",
-			   MAJOR(part_devt(part)), MINOR(part_devt(part)),
-			   (unsigned long long)part_nr_sects_read(part) >> 1,
-			   disk_name(sgp, part->partno, buf));
+			   MAJOR(part->bd_dev), MINOR(part->bd_dev),
+			   bdev_nr_sectors(part) >> 1,
+			   disk_name(sgp, part->bd_partno, buf));
 	disk_part_iter_exit(&piter);
 
 	return 0;
···
 };
 #endif
 
-
-static struct kobject *base_probe(dev_t devt, int *partno, void *data)
-{
-	if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
-		/* Make old-style 2.4 aliases work */
-		request_module("block-major-%d", MAJOR(devt));
-	return NULL;
-}
-
 static int __init genhd_device_init(void)
 {
 	int error;
···
 	error = class_register(&block_class);
 	if (unlikely(error))
 		return error;
-	bdev_map = kobj_map_init(base_probe, &block_class_lock);
 	blk_dev_init();
 
 	register_blkdev(BLOCK_EXT_MAJOR, "blkext");
···
 ssize_t part_size_show(struct device *dev,
 		       struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-
-	return sprintf(buf, "%llu\n",
-		(unsigned long long)part_nr_sects_read(p));
+	return sprintf(buf, "%llu\n", bdev_nr_sectors(dev_to_bdev(dev)));
 }
 
 ssize_t part_stat_show(struct device *dev,
 		       struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-	struct request_queue *q = part_to_disk(p)->queue;
+	struct block_device *bdev = dev_to_bdev(dev);
+	struct request_queue *q = bdev->bd_disk->queue;
 	struct disk_stats stat;
 	unsigned int inflight;
 
-	part_stat_read_all(p, &stat);
+	part_stat_read_all(bdev, &stat);
 	if (queue_is_mq(q))
-		inflight = blk_mq_in_flight(q, p);
+		inflight = blk_mq_in_flight(q, bdev);
 	else
-		inflight = part_in_flight(p);
+		inflight = part_in_flight(bdev);
 
 	return sprintf(buf,
 		"%8lu %8lu %8llu %8u "
···
 ssize_t part_inflight_show(struct device *dev, struct device_attribute *attr,
 			   char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-	struct request_queue *q = part_to_disk(p)->queue;
+	struct block_device *bdev = dev_to_bdev(dev);
+	struct request_queue *q = bdev->bd_disk->queue;
 	unsigned int inflight[2];
 
 	if (queue_is_mq(q))
-		blk_mq_in_flight_rw(q, p, inflight);
+		blk_mq_in_flight_rw(q, bdev, inflight);
 	else
-		part_in_flight_rw(p, inflight);
+		part_in_flight_rw(bdev, inflight);
 
 	return sprintf(buf, "%8u %8u\n", inflight[0], inflight[1]);
 }
···
 ssize_t part_fail_show(struct device *dev,
 		       struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-
-	return sprintf(buf, "%d\n", p->make_it_fail);
+	return sprintf(buf, "%d\n", dev_to_bdev(dev)->bd_make_it_fail);
 }
 
 ssize_t part_fail_store(struct device *dev,
 			struct device_attribute *attr,
 			const char *buf, size_t count)
 {
-	struct hd_struct *p = dev_to_part(dev);
 	int i;
 
 	if (count > 0 && sscanf(buf, "%d", &i) > 0)
-		p->make_it_fail = (i == 0) ? 0 : 1;
+		dev_to_bdev(dev)->bd_make_it_fail = i;
 
 	return count;
 }
···
  *
  * This function releases all allocated resources of the gendisk.
  *
- * The struct gendisk refcount is incremented with get_gendisk() or
- * get_disk_and_module(), and its refcount is decremented with
- * put_disk_and_module() or put_disk(). Once the refcount reaches 0 this
- * function is called.
- *
  * Drivers which used __device_add_disk() have a gendisk with a request_queue
  * assigned. Since the request_queue sits on top of the gendisk for these
  * drivers we also call blk_put_queue() for them, and we expect the
···
 	disk_release_events(disk);
 	kfree(disk->random);
 	disk_replace_part_tbl(disk, NULL);
-	hd_free_part(&disk->part0);
+	bdput(disk->part0);
 	if (disk->queue)
 		blk_put_queue(disk->queue);
 	kfree(disk);
···
 {
 	struct gendisk *gp = v;
 	struct disk_part_iter piter;
-	struct hd_struct *hd;
+	struct block_device *hd;
 	char buf[BDEVNAME_SIZE];
 	unsigned int inflight;
 	struct disk_stats stat;
···
 			   "%lu %lu %lu %u "
 			   "%lu %u"
 			   "\n",
-			   MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
-			   disk_name(gp, hd->partno, buf),
+			   MAJOR(hd->bd_dev), MINOR(hd->bd_dev),
+			   disk_name(gp, hd->bd_partno, buf),
 			   stat.ios[STAT_READ],
 			   stat.merges[STAT_READ],
 			   stat.sectors[STAT_READ],
···
 	class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
 	while ((dev = class_dev_iter_next(&iter))) {
 		struct gendisk *disk = dev_to_disk(dev);
-		struct hd_struct *part;
+		struct block_device *part;
 
 		if (strcmp(dev_name(dev), name))
 			continue;
···
 				     MINOR(dev->devt) + partno);
 			break;
 		}
-		part = disk_get_part(disk, partno);
+		part = bdget_disk(disk, partno);
 		if (part) {
-			devt = part_devt(part);
-			disk_put_part(part);
+			devt = part->bd_dev;
+			bdput(part);
 			break;
 		}
-		disk_put_part(part);
 	}
 	class_dev_iter_exit(&iter);
 	return devt;
···
 	if (!disk)
 		return NULL;
 
-	disk->part0.dkstats = alloc_percpu(struct disk_stats);
-	if (!disk->part0.dkstats)
+	disk->part0 = bdev_alloc(disk, 0);
+	if (!disk->part0)
 		goto out_free_disk;
 
-	init_rwsem(&disk->lookup_sem);
 	disk->node_id = node_id;
-	if (disk_expand_part_tbl(disk, 0)) {
-		free_percpu(disk->part0.dkstats);
-		goto out_free_disk;
-	}
+	if (disk_expand_part_tbl(disk, 0))
+		goto out_bdput;
 
 	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
-	 * seqcounter to read/update the part0->nr_sects. Still init
-	 * the counter as we can read the sectors in IO submission
-	 * patch using seqence counters.
-	 *
-	 * TODO: Ideally set_capacity() and get_capacity() should be
-	 * converted to make use of bd_mutex and sequence counters.
-	 */
-	hd_sects_seq_init(&disk->part0);
-	if (hd_ref_init(&disk->part0))
-		goto out_free_part0;
+	rcu_assign_pointer(ptbl->part[0], disk->part0);
 
 	disk->minors = minors;
 	rand_initialize_disk(disk);
···
 	device_initialize(disk_to_dev(disk));
 	return disk;
 
-out_free_part0:
-	hd_free_part(&disk->part0);
+out_bdput:
+	bdput(disk->part0);
 out_free_disk:
 	kfree(disk);
 	return NULL;
 }
 EXPORT_SYMBOL(__alloc_disk_node);
-
-/**
- * get_disk_and_module - increments the gendisk and gendisk fops module refcount
- * @disk: the struct gendisk to increment the refcount for
- *
- * This increments the refcount for the struct gendisk, and the gendisk's
- * fops module owner.
- *
- * Context: Any context.
- */
-struct kobject *get_disk_and_module(struct gendisk *disk)
-{
-	struct module *owner;
-	struct kobject *kobj;
-
-	if (!disk->fops)
-		return NULL;
-	owner = disk->fops->owner;
-	if (owner && !try_module_get(owner))
-		return NULL;
-	kobj = kobject_get_unless_zero(&disk_to_dev(disk)->kobj);
-	if (kobj == NULL) {
-		module_put(owner);
-		return NULL;
-	}
-	return kobj;
-
-}
-EXPORT_SYMBOL(get_disk_and_module);
 
 /**
  * put_disk - decrements the gendisk refcount
···
 void put_disk(struct gendisk *disk)
 {
 	if (disk)
-		kobject_put(&disk_to_dev(disk)->kobj);
+		put_device(disk_to_dev(disk));
 }
 EXPORT_SYMBOL(put_disk);
-
-/**
- * put_disk_and_module - decrements the module and gendisk refcount
- * @disk: the struct gendisk to decrement the refcount for
- *
- * This is a counterpart of get_disk_and_module() and thus also of
- * get_gendisk().
- *
- * Context: Any context, but the last reference must not be dropped from
- *          atomic context.
- */
-void put_disk_and_module(struct gendisk *disk)
-{
-	if (disk) {
-		struct module *owner = disk->fops->owner;
-
-		put_disk(disk);
-		module_put(owner);
-	}
-}
-EXPORT_SYMBOL(put_disk_and_module);
 
 static void set_disk_ro_uevent(struct gendisk *gd, int ro)
 {
···
 	kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
 }
 
-void set_device_ro(struct block_device *bdev, int flag)
-{
-	bdev->bd_part->policy = flag;
-}
-
-EXPORT_SYMBOL(set_device_ro);
-
 void set_disk_ro(struct gendisk *disk, int flag)
 {
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 
-	if (disk->part0.policy != flag) {
+	if (disk->part0->bd_read_only != flag) {
 		set_disk_ro_uevent(disk, flag);
-		disk->part0.policy = flag;
+		disk->part0->bd_read_only = flag;
 	}
 
 	disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
 	while ((part = disk_part_iter_next(&piter)))
-		part->policy = flag;
+		part->bd_read_only = flag;
 	disk_part_iter_exit(&piter);
 }
 
···
 {
 	if (!bdev)
 		return 0;
-	return bdev->bd_part->policy;
+	return bdev->bd_read_only;
 }
 
 EXPORT_SYMBOL(bdev_read_only);

block/ioctl.c

···
 	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:
 		/* check if partition is aligned to blocksize */
···
 }
 #endif
 
-int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
-			unsigned cmd, unsigned long arg)
-{
-	struct gendisk *disk = bdev->bd_disk;
-
-	if (disk->fops->ioctl)
-		return disk->fops->ioctl(bdev, mode, cmd, arg);
-
-	return -ENOTTY;
-}
-/*
- * For the record: _GPL here is only because somebody decided to slap it
- * on the previous export.  Sheer idiocy, since it wasn't copyrightable
- * at all and could be open-coded without any exports by anybody who cares.
- */
-EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
-
 #ifdef CONFIG_COMPAT
 /*
  * This is the equivalent of compat_ptr_ioctl(), to be used by block
···
 	return ops->pr_clear(bdev, c.key);
 }
 
-/*
- * Is it an unrecognized ioctl? The correct returns are either
- * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a
- * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl
- * code before returning.
- *
- * Confused drivers sometimes return EINVAL, which is wrong. It
- * means "I understood the ioctl command, but the parameters to
- * it were wrong".
- *
- * We should aim to just fix the broken drivers, the EINVAL case
- * should go away.
- */
-static inline int is_unrecognized_ioctl(int ret)
-{
-	return	ret == -EINVAL ||
-		ret == -ENOTTY ||
-		ret == -ENOIOCTLCMD;
-}
-
 static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode,
 		unsigned cmd, unsigned long arg)
 {
-	int ret;
-
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
-
-	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
-	if (!is_unrecognized_ioctl(ret))
-		return ret;
-
 	fsync_bdev(bdev);
 	invalidate_bdev(bdev);
 	return 0;
···
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
 
-	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
-	if (!is_unrecognized_ioctl(ret))
-		return ret;
 	if (get_user(n, (int __user *)arg))
 		return -EFAULT;
-	set_device_ro(bdev, n);
+	if (bdev->bd_disk->fops->set_read_only) {
+		ret = bdev->bd_disk->fops->set_read_only(bdev, n);
+		if (ret)
+			return ret;
+	}
+	bdev->bd_read_only = n;
 	return 0;
 }
 
···
 	}
 
 	ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
-	if (ret == -ENOIOCTLCMD)
-		return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
+	if (ret != -ENOIOCTLCMD)
+		return ret;
 
-	return ret;
+	if (!bdev->bd_disk->fops->ioctl)
+		return -ENOTTY;
+	return bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
 }
 EXPORT_SYMBOL_GPL(blkdev_ioctl); /* for /dev/raw */
 
···
 {
 	int ret;
 	void __user *argp = compat_ptr(arg);
-	struct inode *inode = file->f_mapping->host;
-	struct block_device *bdev = inode->i_bdev;
+	struct block_device *bdev = I_BDEV(file->f_mapping->host);
 	struct gendisk *disk = bdev->bd_disk;
 	fmode_t mode = file->f_mode;
 	loff_t size;

block/partitions/core.c

···
 	NULL
 };
 
+static void bdev_set_nr_sectors(struct block_device *bdev, sector_t sectors)
+{
+	spin_lock(&bdev->bd_size_lock);
+	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
+	spin_unlock(&bdev->bd_size_lock);
+}
+
 static struct parsed_partitions *allocate_partitions(struct gendisk *hd)
 {
 	struct parsed_partitions *state;
···
 static ssize_t part_partition_show(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-
-	return sprintf(buf, "%d\n", p->partno);
+	return sprintf(buf, "%d\n", dev_to_bdev(dev)->bd_partno);
 }
 
 static ssize_t part_start_show(struct device *dev,
 			       struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-
-	return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
+	return sprintf(buf, "%llu\n", dev_to_bdev(dev)->bd_start_sect);
 }
 
 static ssize_t part_ro_show(struct device *dev,
 			    struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
-	return sprintf(buf, "%d\n", p->policy ? 1 : 0);
+	return sprintf(buf, "%d\n", dev_to_bdev(dev)->bd_read_only);
 }
 
 static ssize_t part_alignment_offset_show(struct device *dev,
 					  struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
+	struct block_device *bdev = dev_to_bdev(dev);
 
 	return sprintf(buf, "%u\n",
-		queue_limit_alignment_offset(&part_to_disk(p)->queue->limits,
-				p->start_sect));
+		queue_limit_alignment_offset(&bdev->bd_disk->queue->limits,
+				bdev->bd_start_sect));
 }
 
 static ssize_t part_discard_alignment_show(struct device *dev,
 					   struct device_attribute *attr, char *buf)
 {
-	struct hd_struct *p = dev_to_part(dev);
+	struct block_device *bdev = dev_to_bdev(dev);
 
 	return sprintf(buf, "%u\n",
-		queue_limit_discard_alignment(&part_to_disk(p)->queue->limits,
-				p->start_sect));
+		queue_limit_discard_alignment(&bdev->bd_disk->queue->limits,
+				bdev->bd_start_sect));
 }
 
 static DEVICE_ATTR(partition, 0444, part_partition_show, NULL);
···
 
 static void part_release(struct device *dev)
 {
-	struct hd_struct *p = dev_to_part(dev);
 	blk_free_devt(dev->devt);
-	hd_free_part(p);
-	kfree(p);
+	bdput(dev_to_bdev(dev));
 }
 
 static int part_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
-	struct hd_struct *part = dev_to_part(dev);
+	struct block_device *part = dev_to_bdev(dev);
 
-	add_uevent_var(env, "PARTN=%u", part->partno);
-	if (part->info && part->info->volname[0])
-		add_uevent_var(env, "PARTNAME=%s", part->info->volname);
+	add_uevent_var(env, "PARTN=%u", part->bd_partno);
+	if (part->bd_meta_info && part->bd_meta_info->volname[0])
+		add_uevent_var(env, "PARTNAME=%s", part->bd_meta_info->volname);
 	return 0;
 }
 
···
 	.uevent		= part_uevent,
 };
 
-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 gendisk *disk = part_to_disk(part);
-
-	/*
-	 * Release the disk reference acquired in delete_partition here.
-	 * We can't release it in hd_struct_free because the final put_device
-	 * needs process context and thus can't be run directly from a
-	 * percpu_ref ->release handler.
-	 */
-	put_device(disk_to_dev(disk));
-
-	part->start_sect = 0;
-	part->nr_sects = 0;
-	part_stat_set_all(part, 0);
-	put_device(part_to_dev(part));
-}
-
-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);
-
-	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.
  */
-void delete_partition(struct hd_struct *part)
+void delete_partition(struct block_device *part)
 {
-	struct gendisk *disk = part_to_disk(part);
+	struct gendisk *disk = part->bd_disk;
 	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(disk));
-	rcu_assign_pointer(ptbl->part[part->partno], NULL);
-	kobject_put(part->holder_dir);
-	device_del(part_to_dev(part));
+	rcu_assign_pointer(ptbl->part[part->bd_partno], NULL);
+	rcu_assign_pointer(ptbl->last_lookup, NULL);
+
+	kobject_put(part->bd_holder_dir);
+	device_del(&part->bd_device);
 
 	/*
-	 * Remove gendisk pointer from idr so that it cannot be looked up
-	 * while RCU period before freeing gendisk is running to prevent
-	 * use-after-free issues. Note that the device number stays
-	 * "in-use" until we really free the gendisk.
+	 * Remove the block device from the inode hash, so that it cannot be
+	 * looked up any more even when openers still hold references.
 	 */
-	blk_invalidate_devt(part_devt(part));
-	percpu_ref_kill(&part->ref);
+	remove_inode_hash(part->bd_inode);
+
+	put_device(&part->bd_device);
 }
 
 static ssize_t whole_disk_show(struct device *dev,
···
  * Must be called either with bd_mutex held, before a disk can be opened or
  * after all disk users are gone.
  */
-static struct hd_struct *add_partition(struct gendisk *disk, int partno,
+static struct block_device *add_partition(struct gendisk *disk, int partno,
 				sector_t start, sector_t len, int flags,
 				struct partition_meta_info *info)
 {
-	struct hd_struct *p;
 	dev_t devt = MKDEV(0, 0);
 	struct device *ddev = disk_to_dev(disk);
 	struct device *pdev;
+	struct block_device *bdev;
 	struct disk_part_tbl *ptbl;
 	const char *dname;
 	int err;
···
 	if (ptbl->part[partno])
 		return ERR_PTR(-EBUSY);
 
-	p = kzalloc(sizeof(*p), GFP_KERNEL);
-	if (!p)
-		return ERR_PTR(-EBUSY);
+	bdev = bdev_alloc(disk, partno);
+	if (!bdev)
+		return ERR_PTR(-ENOMEM);
 
-	p->dkstats = alloc_percpu(struct disk_stats);
-	if (!p->dkstats) {
-		err = -ENOMEM;
-		goto out_free;
-	}
-
-	hd_sects_seq_init(p);
-	pdev = part_to_dev(p);
-
-	p->start_sect = start;
-	p->nr_sects = len;
-	p->partno = partno;
-	p->policy = get_disk_ro(disk);
+	bdev->bd_start_sect = start;
+	bdev_set_nr_sectors(bdev, len);
+	bdev->bd_read_only = get_disk_ro(disk);
 
 	if (info) {
-		struct partition_meta_info *pinfo;
-
-		pinfo = kzalloc_node(sizeof(*pinfo), GFP_KERNEL, disk->node_id);
-		if (!pinfo) {
-			err = -ENOMEM;
-			goto out_free_stats;
-		}
-		memcpy(pinfo, info, sizeof(*info));
-		p->info = pinfo;
+		err = -ENOMEM;
+		bdev->bd_meta_info = kmemdup(info, sizeof(*info), GFP_KERNEL);
+		if (!bdev->bd_meta_info)
+			goto out_bdput;
 	}
 
+	pdev = &bdev->bd_device;
 	dname = dev_name(ddev);
 	if (isdigit(dname[strlen(dname) - 1]))
 		dev_set_name(pdev, "%sp%d", dname, partno);
···
 	pdev->type = &part_type;
 	pdev->parent = ddev;
 
-	err = blk_alloc_devt(p, &devt);
+	err = blk_alloc_devt(bdev, &devt);
 	if (err)
-		goto out_free_info;
+		goto out_bdput;
 	pdev->devt = devt;
 
 	/* delay uevent until 'holders' subdir is created */
···
 		goto out_put;
 
 	err = -ENOMEM;
-	p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
-	if (!p->holder_dir)
+	bdev->bd_holder_dir = kobject_create_and_add("holders", &pdev->kobj);
+	if (!bdev->bd_holder_dir)
 		goto out_del;
 
 	dev_set_uevent_suppress(pdev, 0);
···
 			goto out_del;
 	}
 
-	err = hd_ref_init(p);
-	if (err) {
-		if (flags & ADDPART_FLAG_WHOLEDISK)
-			goto out_remove_file;
-		goto out_del;
-	}
-
 	/* everything is up and running, commence */
-	rcu_assign_pointer(ptbl->part[partno], p);
+	bdev_add(bdev, devt);
+	rcu_assign_pointer(ptbl->part[partno], bdev);
 
 	/* suppress uevent if the disk suppresses it */
 	if (!dev_get_uevent_suppress(ddev))
 		kobject_uevent(&pdev->kobj, KOBJ_ADD);
-	return p;
+	return bdev;
 
-out_free_info:
-	kfree(p->info);
-out_free_stats:
-	free_percpu(p->dkstats);
-out_free:
-	kfree(p);
+out_bdput:
+	bdput(bdev);
 	return ERR_PTR(err);
-out_remove_file:
-	device_remove_file(pdev, &dev_attr_whole_disk);
 out_del:
-	kobject_put(p->holder_dir);
+	kobject_put(bdev->bd_holder_dir);
 	device_del(pdev);
 out_put:
 	put_device(pdev);
···
 		sector_t length, int skip_partno)
 {
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *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)
+		if (part->bd_partno == skip_partno ||
+		    start >= part->bd_start_sect + bdev_nr_sectors(part) ||
+		    start + length <= part->bd_start_sect)
 			continue;
 		overlap = true;
 		break;
···
 int bdev_add_partition(struct block_device *bdev, int partno,
 		sector_t start, sector_t length)
 {
-	struct hd_struct *part;
+	struct block_device *part;
 
 	mutex_lock(&bdev->bd_mutex);
 	if (partition_overlaps(bdev->bd_disk, start, length, -1)) {
···
 
 int bdev_del_partition(struct block_device *bdev, int partno)
 {
-	struct block_device *bdevp;
-	struct hd_struct *part = NULL;
+	struct block_device *part;
 	int ret;
 
-	bdevp = bdget_disk(bdev->bd_disk, partno);
-	if (!bdevp)
+	part = bdget_disk(bdev->bd_disk, partno);
+	if (!part)
 		return -ENXIO;
 
-	mutex_lock(&bdevp->bd_mutex);
+	mutex_lock(&part->bd_mutex);
 	mutex_lock_nested(&bdev->bd_mutex, 1);
 
-	ret = -ENXIO;
-	part = disk_get_part(bdev->bd_disk, partno);
-	if (!part)
-		goto out_unlock;
-
 	ret = -EBUSY;
-	if (bdevp->bd_openers)
+	if (part->bd_openers)
 		goto out_unlock;
 
-	sync_blockdev(bdevp);
-	invalidate_bdev(bdevp);
+	sync_blockdev(part);
+	invalidate_bdev(part);
 
 	delete_partition(part);
 	ret = 0;
 out_unlock:
 	mutex_unlock(&bdev->bd_mutex);
-	mutex_unlock(&bdevp->bd_mutex);
-	bdput(bdevp);
-	if (part)
-		disk_put_part(part);
+	mutex_unlock(&part->bd_mutex);
+	bdput(part);
 	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;
+	struct block_device *part;
 	int ret = 0;
 
-	part = disk_get_part(bdev->bd_disk, partno);
+	part = bdget_disk(bdev->bd_disk, partno);
 	if (!part)
 		return -ENXIO;
 
-	ret = -ENOMEM;
-	bdevp = bdget_part(part);
-	if (!bdevp)
-		goto out_put_part;
-
-	mutex_lock(&bdevp->bd_mutex);
+	mutex_lock(&part->bd_mutex);
 	mutex_lock_nested(&bdev->bd_mutex, 1);
-
 	ret = -EINVAL;
-	if (start != part->start_sect)
+	if (start != part->bd_start_sect)
 		goto out_unlock;
 
 	ret = -EBUSY;
 	if (partition_overlaps(bdev->bd_disk, start, length, partno))
 		goto out_unlock;
 
-	part_nr_sects_write(part, length);
-	bd_set_nr_sectors(bdevp, length);
+	bdev_set_nr_sectors(part, length);
 
 	ret = 0;
 out_unlock:
-	mutex_unlock(&bdevp->bd_mutex);
+	mutex_unlock(&part->bd_mutex);
 	mutex_unlock(&bdev->bd_mutex);
-	bdput(bdevp);
-out_put_part:
-	disk_put_part(part);
+	bdput(part);
 	return ret;
 }
 
···
 int blk_drop_partitions(struct block_device *bdev)
 {
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 
 	if (bdev->bd_part_count)
 		return -EBUSY;
···
 {
 	sector_t size = state->parts[p].size;
 	sector_t from = state->parts[p].from;
-	struct hd_struct *part;
+	struct block_device *part;
 
 	if (!size)
 		return true;
···
 
 	if (IS_BUILTIN(CONFIG_BLK_DEV_MD) &&
 	    (state->parts[p].flags & ADDPART_FLAG_RAID))
-		md_autodetect_dev(part_to_dev(part)->devt);
+		md_autodetect_dev(part->bd_dev);
 
 	return true;
 }

drivers/block/amiflop.c

···
 	int busy;			/* true when drive is active */
 	int dirty;			/* true when trackbuf is not on disk */
 	int status;			/* current error code for unit */
-	struct gendisk *gendisk;
+	struct gendisk *gendisk[2];
 	struct blk_mq_tag_set tag_set;
 };
 
···
 		return -EBUSY;
 	}
 
+	if (unit[drive].type->code == FD_NODRIVE) {
+		mutex_unlock(&amiflop_mutex);
+		return -ENXIO;
+	}
+
 	if (mode & (FMODE_READ|FMODE_WRITE)) {
 		bdev_check_media_change(bdev);
 		if (mode & FMODE_WRITE) {
···
 	unit[drive].dtype=&data_types[system];
 	unit[drive].blocks=unit[drive].type->heads*unit[drive].type->tracks*
 		data_types[system].sects*unit[drive].type->sect_mult;
-	set_capacity(unit[drive].gendisk, unit[drive].blocks);
+	set_capacity(unit[drive].gendisk[system], unit[drive].blocks);
 
 	printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
 	       unit[drive].type->name, data_types[system].name);
···
 	.queue_rq = amiflop_queue_rq,
 };
 
-static struct gendisk *fd_alloc_disk(int drive)
+static int fd_alloc_disk(int drive, int system)
 {
 	struct gendisk *disk;
 
 	disk = alloc_disk(1);
 	if (!disk)
 		goto out;
-
-	disk->queue = blk_mq_init_sq_queue(&unit[drive].tag_set, &amiflop_mq_ops,
-						2, BLK_MQ_F_SHOULD_MERGE);
-	if (IS_ERR(disk->queue)) {
-		disk->queue = NULL;
+	disk->queue = blk_mq_init_queue(&unit[drive].tag_set);
+	if (IS_ERR(disk->queue))
 		goto out_put_disk;
-	}
 
-	unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
-	if (!unit[drive].trackbuf)
-		goto out_cleanup_queue;
+	disk->major = FLOPPY_MAJOR;
+	disk->first_minor = drive + system;
+	disk->fops = &floppy_fops;
+	disk->events = DISK_EVENT_MEDIA_CHANGE;
+	if (system)
+		sprintf(disk->disk_name, "fd%d_msdos", drive);
+	else
+		sprintf(disk->disk_name, "fd%d", drive);
+	disk->private_data = &unit[drive];
+	set_capacity(disk, 880 * 2);
 
-	return disk;
+	unit[drive].gendisk[system] = disk;
+	add_disk(disk);
+	return 0;
 
-out_cleanup_queue:
-	blk_cleanup_queue(disk->queue);
-	disk->queue = NULL;
-	blk_mq_free_tag_set(&unit[drive].tag_set);
 out_put_disk:
+	disk->queue = NULL;
 	put_disk(disk);
 out:
+	return -ENOMEM;
+}
+
+static int fd_alloc_drive(int drive)
+{
+	unit[drive].trackbuf = kmalloc(FLOPPY_MAX_SECTORS * 512, GFP_KERNEL);
+	if (!unit[drive].trackbuf)
+		goto out;
+
+	memset(&unit[drive].tag_set, 0, sizeof(unit[drive].tag_set));
+	unit[drive].tag_set.ops = &amiflop_mq_ops;
+	unit[drive].tag_set.nr_hw_queues = 1;
+	unit[drive].tag_set.nr_maps = 1;
+	unit[drive].tag_set.queue_depth = 2;
+	unit[drive].tag_set.numa_node = NUMA_NO_NODE;
+	unit[drive].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+	if (blk_mq_alloc_tag_set(&unit[drive].tag_set))
+		goto out_cleanup_trackbuf;
+
+	pr_cont(" fd%d", drive);
+
+	if (fd_alloc_disk(drive, 0) || fd_alloc_disk(drive, 1))
+		goto out_cleanup_tagset;
+	return 0;
+
+out_cleanup_tagset:
+	blk_mq_free_tag_set(&unit[drive].tag_set);
+out_cleanup_trackbuf:
+	kfree(unit[drive].trackbuf);
+out:
 	unit[drive].type->code = FD_NODRIVE;
-	return NULL;
+	return -ENOMEM;
 }
 
 static int __init fd_probe_drives(void)
···
 	drives=0;
 	nomem=0;
 	for(drive=0;drive<FD_MAX_UNITS;drive++) {
-		struct gendisk *disk;
 		fd_probe(drive);
 		if (unit[drive].type->code == FD_NODRIVE)
 			continue;
 
-		disk = fd_alloc_disk(drive);
-		if (!disk) {
+		if (fd_alloc_drive(drive) < 0) {
 			pr_cont(" no mem for fd%d", drive);
 			nomem = 1;
 			continue;
 		}
-		unit[drive].gendisk = disk;
 		drives++;
-
-		pr_cont(" fd%d",drive);
-		disk->major = FLOPPY_MAJOR;
-		disk->first_minor = drive;
-		disk->fops = &floppy_fops;
-		disk->events = DISK_EVENT_MEDIA_CHANGE;
-		sprintf(disk->disk_name, "fd%d", drive);
-		disk->private_data = &unit[drive];
-		set_capacity(disk, 880*2);
-		add_disk(disk);
 	}
 	if ((drives > 0) || (nomem == 0)) {
 		if (drives == 0)
···
 	return -ENOMEM;
 }
  
-static struct kobject *floppy_find(dev_t dev, int *part, void *data)
-{
-	int drive = *part & 3;
-	if (unit[drive].type->code == FD_NODRIVE)
-		return NULL;
-	*part = 0;
-	return get_disk_and_module(unit[drive].gendisk);
-}
-
 static int __init amiga_floppy_probe(struct platform_device *pdev)
 {
 	int i, ret;
···
 	ret = -ENODEV;
 	if (fd_probe_drives() < 1) /* No usable drives */
 		goto out_probe;
-
-	blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
-				floppy_find, NULL, NULL);
 
 	/* initialize variables */
 	timer_setup(&motor_on_timer, motor_on_callback, 0);

drivers/block/aoe/aoecmd.c

···
 aoecmd_sleepwork(struct work_struct *work)
 {
 	struct aoedev *d = container_of(work, struct aoedev, work);
-	struct block_device *bd;
-	u64 ssize;
 
 	if (d->flags & DEVFL_GDALLOC)
 		aoeblk_gdalloc(d);
 
 	if (d->flags & DEVFL_NEWSIZE) {
-		ssize = get_capacity(d->gd);
-		bd = bdget_disk(d->gd, 0);
-		if (bd) {
-			bd_set_nr_sectors(bd, ssize);
-			bdput(bd);
-		}
+		set_capacity_and_notify(d->gd, d->ssize);
+
 		spin_lock_irq(&d->lock);
 		d->flags |= DEVFL_UP;
 		d->flags &= ~DEVFL_NEWSIZE;
···
 	d->geo.start = 0;
 	if (d->flags & (DEVFL_GDALLOC|DEVFL_NEWSIZE))
 		return;
-	if (d->gd != NULL) {
-		set_capacity(d->gd, ssize);
+	if (d->gd != NULL)
 		d->flags |= DEVFL_NEWSIZE;
-	} else
+	else
 		d->flags |= DEVFL_GDALLOC;
 	schedule_work(&d->work);
 }

drivers/block/ataflop.c

···
 	unsigned int wpstat;	/* current state of WP signal (for
 				   disk change detection) */
 	int flags;		/* flags */
-	struct gendisk *disk;
+	struct gendisk *disk[NUM_DISK_MINORS];
 	int ref;
 	int type;
 	struct blk_mq_tag_set tag_set;
···
 
 static int do_format(int drive, int type, struct atari_format_descr *desc)
 {
-	struct request_queue *q = unit[drive].disk->queue;
+	struct request_queue *q;
 	unsigned char	*p;
 	int sect, nsect;
 	unsigned long	flags;
 	int ret;
 
+	if (type)
+		type--;
+
+	q = unit[drive].disk[type]->queue;
 	blk_mq_freeze_queue(q);
 	blk_mq_quiesce_queue(q);
 
···
 	local_irq_restore(flags);
 
 	if (type) {
-		if (--type >= NUM_DISK_MINORS ||
+		if (type >= NUM_DISK_MINORS ||
 		    minor2disktype[type].drive_types > DriveType) {
 			ret = -EINVAL;
 			goto out;
···
 			    if (SUDT[-1].blocks > ReqBlock) {
 				/* try another disk type */
 				SUDT--;
-				set_capacity(unit[SelectedDrive].disk,
+				set_capacity(unit[SelectedDrive].disk[0],
 							SUDT->blocks);
 			    } else
 				Probing = 0;
···
 /* record not found, but not probing. Maybe stretch wrong ? Restart probing */
 			if (SUD.autoprobe) {
 				SUDT = atari_disk_type + StartDiskType[DriveType];
-				set_capacity(unit[SelectedDrive].disk,
+				set_capacity(unit[SelectedDrive].disk[0],
 							SUDT->blocks);
 				Probing = 1;
 			}
···
 		if (!UDT) {
 			Probing = 1;
 			UDT = atari_disk_type + StartDiskType[DriveType];
-			set_capacity(floppy->disk, UDT->blocks);
+			set_capacity(bd->rq->rq_disk, UDT->blocks);
 			UD.autoprobe = 1;
 		}
 	} 
···
 		}
 		type = minor2disktype[type].index;
 		UDT = &atari_disk_type[type];
-		set_capacity(floppy->disk, UDT->blocks);
+		set_capacity(bd->rq->rq_disk, UDT->blocks);
 		UD.autoprobe = 0;
 	}
 
···
 				    printk (KERN_INFO "floppy%d: setting %s %p!\n",
 				        drive, dtp->name, dtp);
 				UDT = dtp;
-				set_capacity(floppy->disk, UDT->blocks);
+				set_capacity(disk, UDT->blocks);
 
 				if (cmd == FDDEFPRM) {
 				  /* save settings as permanent default type */
···
 			return -EINVAL;
 
 		UDT = dtp;
-		set_capacity(floppy->disk, UDT->blocks);
+		set_capacity(disk, UDT->blocks);
 
 		return 0;
 	case FDMSGON:
···
 		UDT = NULL;
 		/* MSch: invalidate default_params */
 		default_params[drive].blocks  = 0;
-		set_capacity(floppy->disk, MAX_DISK_SIZE * 2);
+		set_capacity(disk, MAX_DISK_SIZE * 2);
 		fallthrough;
 	case FDFMTEND:
 	case FDFLUSH:
···
 	.commit_rqs = ataflop_commit_rqs,
 };
 
-static struct kobject *floppy_find(dev_t dev, int *part, void *data)
+static int ataflop_alloc_disk(unsigned int drive, unsigned int type)
 {
-	int drive = *part & 3;
-	int type  = *part >> 2;
+	struct gendisk *disk;
+	int ret;
+
+	disk = alloc_disk(1);
+	if (!disk)
+		return -ENOMEM;
+
+	disk->queue = blk_mq_init_queue(&unit[drive].tag_set);
+	if (IS_ERR(disk->queue)) {
+		ret = PTR_ERR(disk->queue);
+		disk->queue = NULL;
+		put_disk(disk);
+		return ret;
+	}
+
+	disk->major = FLOPPY_MAJOR;
+	disk->first_minor = drive + (type << 2);
+	sprintf(disk->disk_name, "fd%d", drive);
+	disk->fops = &floppy_fops;
+	disk->events = DISK_EVENT_MEDIA_CHANGE;
+	disk->private_data = &unit[drive];
+	set_capacity(disk, MAX_DISK_SIZE * 2);
+
+	unit[drive].disk[type] = disk;
+	return 0;
+}
+
+static DEFINE_MUTEX(ataflop_probe_lock);
+
+static void ataflop_probe(dev_t dev)
+{
+	int drive = MINOR(dev) & 3;
+	int type  = MINOR(dev) >> 2;
+
 	if (drive >= FD_MAX_UNITS || type > NUM_DISK_MINORS)
-		return NULL;
-	*part = 0;
-	return get_disk_and_module(unit[drive].disk);
+		return;
+	mutex_lock(&ataflop_probe_lock);
+	if (!unit[drive].disk[type]) {
+		if (ataflop_alloc_disk(drive, type) == 0)
+			add_disk(unit[drive].disk[type]);
+	}
+	mutex_unlock(&ataflop_probe_lock);
 }
 
 static int __init atari_floppy_init (void)
···
 		/* Amiga, Mac, ... don't have Atari-compatible floppy :-) */
 		return -ENODEV;
 
-	if (register_blkdev(FLOPPY_MAJOR,"fd"))
-		return -EBUSY;
+	mutex_lock(&ataflop_probe_lock);
+	ret = __register_blkdev(FLOPPY_MAJOR, "fd", ataflop_probe);
+	if (ret)
+		goto out_unlock;
 
 	for (i = 0; i < FD_MAX_UNITS; i++) {
-		unit[i].disk = alloc_disk(1);
-		if (!unit[i].disk) {
-			ret = -ENOMEM;
+		memset(&unit[i].tag_set, 0, sizeof(unit[i].tag_set));
+		unit[i].tag_set.ops = &ataflop_mq_ops;
+		unit[i].tag_set.nr_hw_queues = 1;
+		unit[i].tag_set.nr_maps = 1;
+		unit[i].tag_set.queue_depth = 2;
+		unit[i].tag_set.numa_node = NUMA_NO_NODE;
+		unit[i].tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+		ret = blk_mq_alloc_tag_set(&unit[i].tag_set);
+		if (ret)
 			goto err;
-		}
 
-		unit[i].disk->queue = blk_mq_init_sq_queue(&unit[i].tag_set,
-							   &ataflop_mq_ops, 2,
-							   BLK_MQ_F_SHOULD_MERGE);
-		if (IS_ERR(unit[i].disk->queue)) {
-			put_disk(unit[i].disk);
-			ret = PTR_ERR(unit[i].disk->queue);
-			unit[i].disk->queue = NULL;
+		ret = ataflop_alloc_disk(i, 0);
+		if (ret) {
+			blk_mq_free_tag_set(&unit[i].tag_set);
 			goto err;
 		}
 	}
···
 	for (i = 0; i < FD_MAX_UNITS; i++) {
 		unit[i].track = -1;
 		unit[i].flags = 0;
-		unit[i].disk->major = FLOPPY_MAJOR;
-		unit[i].disk->first_minor = i;
-		sprintf(unit[i].disk->disk_name, "fd%d", i);
-		unit[i].disk->fops = &floppy_fops;
-		unit[i].disk->events = DISK_EVENT_MEDIA_CHANGE;
-		unit[i].disk->private_data = &unit[i];
-		set_capacity(unit[i].disk, MAX_DISK_SIZE * 2);
-		add_disk(unit[i].disk);
+		add_disk(unit[i].disk[0]);
 	}
-
-	blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
-				floppy_find, NULL, NULL);
 
 	printk(KERN_INFO "Atari floppy driver: max. %cD, %strack buffering\n",
 	       DriveType == 0 ? 'D' : DriveType == 1 ? 'H' : 'E',
···
 
 err:
 	while (--i >= 0) {
-		struct gendisk *disk = unit[i].disk;
-
-		blk_cleanup_queue(disk->queue);
+		blk_cleanup_queue(unit[i].disk[0]->queue);
+		put_disk(unit[i].disk[0]);
 		blk_mq_free_tag_set(&unit[i].tag_set);
-		put_disk(unit[i].disk);
 	}
 
 	unregister_blkdev(FLOPPY_MAJOR, "fd");
+out_unlock:
+	mutex_unlock(&ataflop_probe_lock);
 	return ret;
 }
 
···
 
 static void __exit atari_floppy_exit(void)
 {
-	int i;
-	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
+	int i, type;
+
 	for (i = 0; i < FD_MAX_UNITS; i++) {
-		del_gendisk(unit[i].disk);
-		blk_cleanup_queue(unit[i].disk->queue);
+		for (type = 0; type < NUM_DISK_MINORS; type++) {
+			if (!unit[i].disk[type])
+				continue;
+			del_gendisk(unit[i].disk[type]);
+			blk_cleanup_queue(unit[i].disk[type]->queue);
+			put_disk(unit[i].disk[type]);
+		}
 		blk_mq_free_tag_set(&unit[i].tag_set);
-		put_disk(unit[i].disk);
 	}
 	unregister_blkdev(FLOPPY_MAJOR, "fd");
 

drivers/block/brd.c

···
 	kfree(brd);
 }
 
-static struct brd_device *brd_init_one(int i, bool *new)
+static void brd_probe(dev_t dev)
 {
 	struct brd_device *brd;
+	int i = MINOR(dev) / max_part;
 
-	*new = false;
+	mutex_lock(&brd_devices_mutex);
 	list_for_each_entry(brd, &brd_devices, brd_list) {
 		if (brd->brd_number == i)
-			goto out;
+			goto out_unlock;
 	}
 
 	brd = brd_alloc(i);
···
 		add_disk(brd->brd_disk);
 		list_add_tail(&brd->brd_list, &brd_devices);
 	}
-	*new = true;
-out:
-	return brd;
+
+out_unlock:
+	mutex_unlock(&brd_devices_mutex);
 }
 
 static void brd_del_one(struct brd_device *brd)
···
 	list_del(&brd->brd_list);
 	del_gendisk(brd->brd_disk);
 	brd_free(brd);
-}
-
-static struct kobject *brd_probe(dev_t dev, int *part, void *data)
-{
-	struct brd_device *brd;
-	struct kobject *kobj;
-	bool new;
-
-	mutex_lock(&brd_devices_mutex);
-	brd = brd_init_one(MINOR(dev) / max_part, &new);
-	kobj = brd ? get_disk_and_module(brd->brd_disk) : NULL;
-	mutex_unlock(&brd_devices_mutex);
-
-	if (new)
-		*part = 0;
-
-	return kobj;
 }
 
 static inline void brd_check_and_reset_par(void)
···
 	 *	dynamically.
 	 */
 
-	if (register_blkdev(RAMDISK_MAJOR, "ramdisk"))
+	if (__register_blkdev(RAMDISK_MAJOR, "ramdisk", brd_probe))
 		return -EIO;
 
 	brd_check_and_reset_par();
 
+	mutex_lock(&brd_devices_mutex);
 	for (i = 0; i < rd_nr; i++) {
 		brd = brd_alloc(i);
 		if (!brd)
···
 		brd->brd_disk->queue = brd->brd_queue;
 		add_disk(brd->brd_disk);
 	}
-
-	blk_register_region(MKDEV(RAMDISK_MAJOR, 0), 1UL << MINORBITS,
-				  THIS_MODULE, brd_probe, NULL, NULL);
+	mutex_unlock(&brd_devices_mutex);
 
 	pr_info("brd: module loaded\n");
 	return 0;
···
 		list_del(&brd->brd_list);
 		brd_free(brd);
 	}
+	mutex_unlock(&brd_devices_mutex);
 	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
 
 	pr_info("brd: module NOT loaded !!!\n");
···
 	list_for_each_entry_safe(brd, next, &brd_devices, brd_list)
 		brd_del_one(brd);
 
-	blk_unregister_region(MKDEV(RAMDISK_MAJOR, 0), 1UL << MINORBITS);
 	unregister_blkdev(RAMDISK_MAJOR, "ramdisk");
 
 	pr_info("brd: module unloaded\n");

drivers/block/drbd/drbd_main.c

···
 {
 	char ppb[10];
 
-	set_capacity(device->vdisk, size);
-	revalidate_disk_size(device->vdisk, false);
+	set_capacity_and_notify(device->vdisk, size);
 
 	drbd_info(device, "size = %s (%llu KB)\n",
 		ppsize(ppb, size>>1), (unsigned long long)size>>1);
···
 	}
 	D_ASSERT(device, first_peer_device(device)->connection->net_conf == NULL);
 
-	set_capacity(device->vdisk, 0);
-	revalidate_disk_size(device->vdisk, false);
+	set_capacity_and_notify(device->vdisk, 0);
 	if (device->bitmap) {
 		/* maybe never allocated. */
 		drbd_bm_resize(device, 0, 1);

drivers/block/drbd/drbd_receiver.c

···
 	if (c_min_rate == 0)
 		return false;
 
-	curr_events = (int)part_stat_read_accum(&disk->part0, sectors) -
+	curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
 			atomic_read(&device->rs_sect_ev);
 
 	if (atomic_read(&device->ap_actlog_cnt)

drivers/block/drbd/drbd_worker.c

···
 	atomic_set(&device->rs_sect_in, 0);
 	atomic_set(&device->rs_sect_ev, 0);
 	device->rs_in_flight = 0;
-	device->rs_last_events = (int)part_stat_read_accum(&disk->part0, sectors);
+	device->rs_last_events =
+		(int)part_stat_read_accum(disk->part0, sectors);
 
 	/* Updating the RCU protected object in place is necessary since
 	   this function gets called from atomic context.

drivers/block/floppy.c

···
 static struct floppy_drive_struct drive_state[N_DRIVE];
 static struct floppy_write_errors write_errors[N_DRIVE];
 static struct timer_list motor_off_timer[N_DRIVE];
-static struct gendisk *disks[N_DRIVE];
 static struct blk_mq_tag_set tag_sets[N_DRIVE];
 static struct block_device *opened_bdev[N_DRIVE];
 static DEFINE_MUTEX(open_lock);
···
 	{ 1600,10,2,80,0,0x25,0x02,0xDF,0x2E,"D800"  },	/* 30 800KB 3.5"    */
 	{ 3200,20,2,80,0,0x1C,0x00,0xCF,0x2C,"H1600" }, /* 31 1.6MB 3.5"    */
 };
+
+static struct gendisk *disks[N_DRIVE][ARRAY_SIZE(floppy_type)];
 
 #define SECTSIZE (_FD_SECTSIZE(*floppy))
 
···
 
 	new_dev = MINOR(bdev->bd_dev);
 	drive_state[drive].fd_device = new_dev;
-	set_capacity(disks[drive], floppy_sizes[new_dev]);
+	set_capacity(disks[drive][ITYPE(new_dev)], floppy_sizes[new_dev]);
 	if (old_dev != -1 && old_dev != new_dev) {
 		if (buffer_drive == drive)
 			buffer_track = -1;
···
 	return true;
 }
 
-static struct kobject *floppy_find(dev_t dev, int *part, void *data)
+static int floppy_alloc_disk(unsigned int drive, unsigned int type)
 {
-	int drive = (*part & 3) | ((*part & 0x80) >> 5);
-	if (drive >= N_DRIVE || !floppy_available(drive))
-		return NULL;
-	if (((*part >> 2) & 0x1f) >= ARRAY_SIZE(floppy_type))
-		return NULL;
-	*part = 0;
-	return get_disk_and_module(disks[drive]);
+	struct gendisk *disk;
+	int err;
+
+	disk = alloc_disk(1);
+	if (!disk)
+		return -ENOMEM;
+
+	disk->queue = blk_mq_init_queue(&tag_sets[drive]);
+	if (IS_ERR(disk->queue)) {
+		err = PTR_ERR(disk->queue);
+		disk->queue = NULL;
+		put_disk(disk);
+		return err;
+	}
+
+	blk_queue_bounce_limit(disk->queue, BLK_BOUNCE_HIGH);
+	blk_queue_max_hw_sectors(disk->queue, 64);
+	disk->major = FLOPPY_MAJOR;
+	disk->first_minor = TOMINOR(drive) | (type << 2);
+	disk->fops = &floppy_fops;
+	disk->events = DISK_EVENT_MEDIA_CHANGE;
+	if (type)
+		sprintf(disk->disk_name, "fd%d_type%d", drive, type);
+	else
+		sprintf(disk->disk_name, "fd%d", drive);
+	/* to be cleaned up... */
+	disk->private_data = (void *)(long)drive;
+	disk->flags |= GENHD_FL_REMOVABLE;
+
+	disks[drive][type] = disk;
+	return 0;
+}
+
+static DEFINE_MUTEX(floppy_probe_lock);
+
+static void floppy_probe(dev_t dev)
+{
+	unsigned int drive = (MINOR(dev) & 3) | ((MINOR(dev) & 0x80) >> 5);
+	unsigned int type = (MINOR(dev) >> 2) & 0x1f;
+
+	if (drive >= N_DRIVE || !floppy_available(drive) ||
+	    type >= ARRAY_SIZE(floppy_type))
+		return;
+
+	mutex_lock(&floppy_probe_lock);
+	if (!disks[drive][type]) {
+		if (floppy_alloc_disk(drive, type) == 0)
+			add_disk(disks[drive][type]);
+	}
+	mutex_unlock(&floppy_probe_lock);
 }
 
 static int __init do_floppy_init(void)
···
 		return -ENOMEM;
 
 	for (drive = 0; drive < N_DRIVE; drive++) {
-		disks[drive] = alloc_disk(1);
-		if (!disks[drive]) {
-			err = -ENOMEM;
+		memset(&tag_sets[drive], 0, sizeof(tag_sets[drive]));
+		tag_sets[drive].ops = &floppy_mq_ops;
+		tag_sets[drive].nr_hw_queues = 1;
+		tag_sets[drive].nr_maps = 1;
+		tag_sets[drive].queue_depth = 2;
+		tag_sets[drive].numa_node = NUMA_NO_NODE;
+		tag_sets[drive].flags = BLK_MQ_F_SHOULD_MERGE;
+		err = blk_mq_alloc_tag_set(&tag_sets[drive]);
+		if (err)
 			goto out_put_disk;
-		}
 
-		disks[drive]->queue = blk_mq_init_sq_queue(&tag_sets[drive],
-							   &floppy_mq_ops, 2,
-							   BLK_MQ_F_SHOULD_MERGE);
-		if (IS_ERR(disks[drive]->queue)) {
-			err = PTR_ERR(disks[drive]->queue);
-			disks[drive]->queue = NULL;
+		err = floppy_alloc_disk(drive, 0);
+		if (err)
 			goto out_put_disk;
-		}
-
-		blk_queue_bounce_limit(disks[drive]->queue, BLK_BOUNCE_HIGH);
-		blk_queue_max_hw_sectors(disks[drive]->queue, 64);
-		disks[drive]->major = FLOPPY_MAJOR;
-		disks[drive]->first_minor = TOMINOR(drive);
-		disks[drive]->fops = &floppy_fops;
-		disks[drive]->events = DISK_EVENT_MEDIA_CHANGE;
-		sprintf(disks[drive]->disk_name, "fd%d", drive);
 
 		timer_setup(&motor_off_timer[drive], motor_off_callback, 0);
 	}
 
-	err = register_blkdev(FLOPPY_MAJOR, "fd");
+	err = __register_blkdev(FLOPPY_MAJOR, "fd", floppy_probe);
 	if (err)
 		goto out_put_disk;
 
 	err = platform_driver_register(&floppy_driver);
 	if (err)
 		goto out_unreg_blkdev;
-
-	blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
-			    floppy_find, NULL, NULL);
 
 	for (i = 0; i < 256; i++)
 		if (ITYPE(i))
···
 	if (fdc_state[0].address == -1) {
 		cancel_delayed_work(&fd_timeout);
 		err = -ENODEV;
-		goto out_unreg_region;
+		goto out_unreg_driver;
 	}
 #if N_FDC > 1
 	fdc_state[1].address = FDC2;
···
 	if (err) {
 		cancel_delayed_work(&fd_timeout);
 		err = -EBUSY;
-		goto out_unreg_region;
+		goto out_unreg_driver;
 	}
 
 	/* initialise drive state */
···
 		if (err)
 			goto out_remove_drives;
 
-		/* to be cleaned up... */
-		disks[drive]->private_data = (void *)(long)drive;
-		disks[drive]->flags |= GENHD_FL_REMOVABLE;
-		device_add_disk(&floppy_device[drive].dev, disks[drive], NULL);
+		device_add_disk(&floppy_device[drive].dev, disks[drive][0],
+				NULL);
 	}
 
 	return 0;
···
 out_remove_drives:
 	while (drive--) {
 		if (floppy_available(drive)) {
-			del_gendisk(disks[drive]);
+			del_gendisk(disks[drive][0]);
 			platform_device_unregister(&floppy_device[drive]);
 		}
 	}
 out_release_dma:
 	if (atomic_read(&usage_count))
 		floppy_release_irq_and_dma();
-out_unreg_region:
-	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
+out_unreg_driver:
 	platform_driver_unregister(&floppy_driver);
 out_unreg_blkdev:
 	unregister_blkdev(FLOPPY_MAJOR, "fd");
 out_put_disk:
 	destroy_workqueue(floppy_wq);
 	for (drive = 0; drive < N_DRIVE; drive++) {
-		if (!disks[drive])
+		if (!disks[drive][0])
 			break;
-		if (disks[drive]->queue) {
-			del_timer_sync(&motor_off_timer[drive]);
-			blk_cleanup_queue(disks[drive]->queue);
-			disks[drive]->queue = NULL;
-			blk_mq_free_tag_set(&tag_sets[drive]);
-		}
-		put_disk(disks[drive]);
+		del_timer_sync(&motor_off_timer[drive]);
+		blk_cleanup_queue(disks[drive][0]->queue);
+		disks[drive][0]->queue = NULL;
+		blk_mq_free_tag_set(&tag_sets[drive]);
+		put_disk(disks[drive][0]);
 	}
 	return err;
 }
···
 
 static void __exit floppy_module_exit(void)
 {
-	int drive;
+	int drive, i;
 
-	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
 	unregister_blkdev(FLOPPY_MAJOR, "fd");
 	platform_driver_unregister(&floppy_driver);
 
···
 		del_timer_sync(&motor_off_timer[drive]);
 
 		if (floppy_available(drive)) {
-			del_gendisk(disks[drive]);
+			for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
+				if (disks[drive][i])
+					del_gendisk(disks[drive][i]);
+			}
 			platform_device_unregister(&floppy_device[drive]);
 		}
-		blk_cleanup_queue(disks[drive]->queue);
+		for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
+			if (disks[drive][i])
+				blk_cleanup_queue(disks[drive][i]->queue);
+		}
 		blk_mq_free_tag_set(&tag_sets[drive]);
 
 		/*
···
 		 * queue reference in put_disk().
 		 */
 		if (!(allowed_drive_mask & (1 << drive)) ||
-		    fdc_state[FDC(drive)].version == FDC_NONE)
-			disks[drive]->queue = NULL;
+		    fdc_state[FDC(drive)].version == FDC_NONE) {
+			for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
+				if (disks[drive][i])
+					disks[drive][i]->queue = NULL;
+			}
+		}
 
-		put_disk(disks[drive]);
+		for (i = 0; i < ARRAY_SIZE(floppy_type); i++) {
+			if (disks[drive][i])
+				put_disk(disks[drive][i]);
+		}
 	}
 
 	cancel_delayed_work_sync(&fd_timeout);

drivers/block/loop.c

···
  */
 static void loop_set_size(struct loop_device *lo, loff_t size)
 {
-	struct block_device *bdev = lo->lo_device;
-
-	bd_set_nr_sectors(bdev, size);
-
-	if (!set_capacity_revalidate_and_notify(lo->lo_disk, size, false))
-		kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
+	if (!set_capacity_and_notify(lo->lo_disk, size))
+		kobject_uevent(&disk_to_dev(lo->lo_disk)->kobj, KOBJ_CHANGE);
 }
 
 static inline int
···
 	while (is_loop_device(f)) {
 		struct loop_device *l;
 
-		if (f->f_mapping->host->i_bdev == bdev)
+		if (f->f_mapping->host->i_rdev == bdev->bd_dev)
 			return -EBADF;
 
-		l = f->f_mapping->host->i_bdev->bd_disk->private_data;
+		l = I_BDEV(f->f_mapping->host)->bd_disk->private_data;
 		if (l->lo_state != Lo_bound) {
 			return -EINVAL;
 		}
···
 	 * file-backed loop devices: discarded regions read back as zero.
 	 */
 	if (S_ISBLK(inode->i_mode) && !lo->lo_encrypt_key_size) {
-		struct request_queue *backingq;
-
-		backingq = bdev_get_queue(inode->i_bdev);
+		struct request_queue *backingq = bdev_get_queue(I_BDEV(inode));
 
 		max_discard_sectors = backingq->limits.max_write_zeroes_sectors;
 		granularity = backingq->limits.discard_granularity ?:
···
 	struct file	*file;
 	struct inode	*inode;
 	struct address_space *mapping;
-	struct block_device *claimed_bdev = NULL;
 	int		error;
 	loff_t		size;
 	bool		partscan;
···
 	 * here to avoid changing device under exclusive owner.
 	 */
 	if (!(mode & FMODE_EXCL)) {
-		claimed_bdev = bdev->bd_contains;
-		error = bd_prepare_to_claim(bdev, claimed_bdev, loop_configure);
+		error = bd_prepare_to_claim(bdev, loop_configure);
 		if (error)
 			goto out_putf;
 	}
···
 	if (error)
 		goto out_unlock;
 
-	set_device_ro(bdev, (lo->lo_flags & LO_FLAGS_READ_ONLY) != 0);
+	set_disk_ro(lo->lo_disk, (lo->lo_flags & LO_FLAGS_READ_ONLY) != 0);
 
 	lo->use_dio = lo->lo_flags & LO_FLAGS_DIRECT_IO;
 	lo->lo_device = bdev;
···
 	size = get_loop_size(lo, file);
 	loop_set_size(lo, size);
 
-	set_blocksize(bdev, S_ISBLK(inode->i_mode) ?
-		      block_size(inode->i_bdev) : PAGE_SIZE);
-
 	lo->lo_state = Lo_bound;
 	if (part_shift)
 		lo->lo_flags |= LO_FLAGS_PARTSCAN;
···
 	mutex_unlock(&loop_ctl_mutex);
 	if (partscan)
 		loop_reread_partitions(lo, bdev);
-	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, loop_configure);
+	if (!(mode & FMODE_EXCL))
+		bd_abort_claiming(bdev, loop_configure);
 	return 0;
 
 out_unlock:
 	mutex_unlock(&loop_ctl_mutex);
 out_bdev:
-	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, loop_configure);
+	if (!(mode & FMODE_EXCL))
+		bd_abort_claiming(bdev, loop_configure);
 out_putf:
 	fput(file);
 out:
···
 	set_capacity(lo->lo_disk, 0);
 	loop_sysfs_exit(lo);
 	if (bdev) {
-		bd_set_nr_sectors(bdev, 0);
 		/* let user-space know about this change */
 		kobject_uevent(&disk_to_dev(bdev->bd_disk)->kobj, KOBJ_CHANGE);
 	}
···
 	return ret;
 }
 
-static struct kobject *loop_probe(dev_t dev, int *part, void *data)
+static void loop_probe(dev_t dev)
 {
+	int idx = MINOR(dev) >> part_shift;
 	struct loop_device *lo;
-	struct kobject *kobj;
-	int err;
+
+	if (max_loop && idx >= max_loop)
+		return;
 
 	mutex_lock(&loop_ctl_mutex);
-	err = loop_lookup(&lo, MINOR(dev) >> part_shift);
-	if (err < 0)
-		err = loop_add(&lo, MINOR(dev) >> part_shift);
-	if (err < 0)
-		kobj = NULL;
-	else
-		kobj = get_disk_and_module(lo->lo_disk);
+	if (loop_lookup(&lo, idx) < 0)
+		loop_add(&lo, idx);
 	mutex_unlock(&loop_ctl_mutex);
-
-	*part = 0;
-	return kobj;
 }
 
 static long loop_control_ioctl(struct file *file, unsigned int cmd,
···
 		goto err_out;
 
 
-	if (register_blkdev(LOOP_MAJOR, "loop")) {
+	if (__register_blkdev(LOOP_MAJOR, "loop", loop_probe)) {
 		err = -EIO;
 		goto misc_out;
 	}
-
-	blk_register_region(MKDEV(LOOP_MAJOR, 0), range,
-				  THIS_MODULE, loop_probe, NULL, NULL);
 
 	/* pre-create number of devices given by config or max_loop */
 	mutex_lock(&loop_ctl_mutex);
···
 
 static void __exit loop_exit(void)
 {
-	unsigned long range;
-
-	range = max_loop ? max_loop << part_shift : 1UL << MINORBITS;
-
 	mutex_lock(&loop_ctl_mutex);
 
 	idr_for_each(&loop_index_idr, &loop_exit_cb, NULL);
 	idr_destroy(&loop_index_idr);
 
-	blk_unregister_region(MKDEV(LOOP_MAJOR, 0), range);
 	unregister_blkdev(LOOP_MAJOR, "loop");
 
 	misc_deregister(&loop_misc);

drivers/block/mtip32xx/mtip32xx.c

···
 	/* Enable the block device and add it to /dev */
 	device_add_disk(&dd->pdev->dev, dd->disk, NULL);
 
-	dd->bdev = bdget_disk(dd->disk, 0);
 	/*
 	 * Now that the disk is active, initialize any sysfs attributes
 	 * managed by the protocol layer.
···
 	return rv;
 
 kthread_run_error:
-	bdput(dd->bdev);
-	dd->bdev = NULL;
-
 	/* Delete our gendisk. This also removes the device from /dev */
 	del_gendisk(dd->disk);
 
···
 	blk_mq_tagset_busy_iter(&dd->tags, mtip_no_dev_cleanup, dd);
 	blk_mq_unquiesce_queue(dd->queue);
 
-	/*
-	 * Delete our gendisk structure. This also removes the device
-	 * from /dev
-	 */
-	if (dd->bdev) {
-		bdput(dd->bdev);
-		dd->bdev = NULL;
-	}
 	if (dd->disk) {
 		if (test_bit(MTIP_DDF_INIT_DONE_BIT, &dd->dd_flag))
 			del_gendisk(dd->disk);
···
 		msleep(20);
 	} while (atomic_read(&dd->irq_workers_active) != 0 &&
 		time_before(jiffies, to));
-
-	if (!dd->sr)
-		fsync_bdev(dd->bdev);
 
 	if (atomic_read(&dd->irq_workers_active) != 0) {
 		dev_warn(&dd->pdev->dev,

drivers/block/mtip32xx/mtip32xx.h

···
 
 	int isr_binding;
 
-	struct block_device *bdev;
-
 	struct list_head online_list; /* linkage for online list */
 
 	struct list_head remove_list; /* linkage for removing list */

drivers/block/nbd.c

···
 	}
 }
 
-static void nbd_size_update(struct nbd_device *nbd, bool start)
+static int nbd_set_size(struct nbd_device *nbd, loff_t bytesize,
+		loff_t blksize)
 {
-	struct nbd_config *config = nbd->config;
-	struct block_device *bdev = bdget_disk(nbd->disk, 0);
-	sector_t nr_sectors = config->bytesize >> 9;
+	if (!blksize)
+		blksize = NBD_DEF_BLKSIZE;
+	if (blksize < 512 || blksize > PAGE_SIZE || !is_power_of_2(blksize))
+		return -EINVAL;
 
-	if (config->flags & NBD_FLAG_SEND_TRIM) {
-		nbd->disk->queue->limits.discard_granularity = config->blksize;
-		nbd->disk->queue->limits.discard_alignment = config->blksize;
+	nbd->config->bytesize = bytesize;
+	nbd->config->blksize = blksize;
+
+	if (!nbd->task_recv)
+		return 0;
+
+	if (nbd->config->flags & NBD_FLAG_SEND_TRIM) {
+		nbd->disk->queue->limits.discard_granularity = blksize;
+		nbd->disk->queue->limits.discard_alignment = blksize;
 		blk_queue_max_discard_sectors(nbd->disk->queue, UINT_MAX);
 	}
-	blk_queue_logical_block_size(nbd->disk->queue, config->blksize);
-	blk_queue_physical_block_size(nbd->disk->queue, config->blksize);
-	set_capacity(nbd->disk, nr_sectors);
-	if (bdev) {
-		if (bdev->bd_disk) {
-			bd_set_nr_sectors(bdev, nr_sectors);
-			if (start)
-				set_blocksize(bdev, config->blksize);
-		} else
-			set_bit(GD_NEED_PART_SCAN, &nbd->disk->state);
-		bdput(bdev);
-	}
-	kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE);
-}
+	blk_queue_logical_block_size(nbd->disk->queue, blksize);
+	blk_queue_physical_block_size(nbd->disk->queue, blksize);
 
-static void nbd_size_set(struct nbd_device *nbd, loff_t blocksize,
-			 loff_t nr_blocks)
-{
-	struct nbd_config *config = nbd->config;
-	config->blksize = blocksize;
-	config->bytesize = blocksize * nr_blocks;
-	if (nbd->task_recv != NULL)
-		nbd_size_update(nbd, false);
+	set_bit(GD_NEED_PART_SCAN, &nbd->disk->state);
+	if (!set_capacity_and_notify(nbd->disk, bytesize >> 9))
+		kobject_uevent(&nbd_to_dev(nbd)->kobj, KOBJ_CHANGE);
+	return 0;
 }
 
 static void nbd_complete_rq(struct request *req)
···
 {
 	if (bdev->bd_openers > 1)
 		return;
-	bd_set_nr_sectors(bdev, 0);
+	set_capacity(bdev->bd_disk, 0);
 }
 
 static void nbd_parse_flags(struct nbd_device *nbd)
···
 		args->index = i;
 		queue_work(nbd->recv_workq, &args->work);
 	}
-	nbd_size_update(nbd, true);
-	return error;
+	return nbd_set_size(nbd, config->bytesize, config->blksize);
 }
 
 static int nbd_start_device_ioctl(struct nbd_device *nbd, struct block_device *bdev)
···
 		nbd_config_put(nbd);
 }
 
-static bool nbd_is_valid_blksize(unsigned long blksize)
-{
-	if (!blksize || !is_power_of_2(blksize) || blksize < 512 ||
-	    blksize > PAGE_SIZE)
-		return false;
-	return true;
-}
-
 static void nbd_set_cmd_timeout(struct nbd_device *nbd, u64 timeout)
 {
 	nbd->tag_set.timeout = timeout * HZ;
···
 	case NBD_SET_SOCK:
 		return nbd_add_socket(nbd, arg, false);
 	case NBD_SET_BLKSIZE:
-		if (!arg)
-			arg = NBD_DEF_BLKSIZE;
-		if (!nbd_is_valid_blksize(arg))
-			return -EINVAL;
-		nbd_size_set(nbd, arg,
-			     div_s64(config->bytesize, arg));
-		return 0;
+		return nbd_set_size(nbd, config->bytesize, arg);
 	case NBD_SET_SIZE:
-		nbd_size_set(nbd, config->blksize,
-			     div_s64(arg, config->blksize));
-		return 0;
+		return nbd_set_size(nbd, arg, config->blksize);
 	case NBD_SET_SIZE_BLOCKS:
-		nbd_size_set(nbd, config->blksize, arg);
-		return 0;
+		return nbd_set_size(nbd, arg * config->blksize,
+				    config->blksize);
 	case NBD_SET_TIMEOUT:
 		nbd_set_cmd_timeout(nbd, arg);
 		return 0;
···
 static void nbd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct nbd_device *nbd = disk->private_data;
-	struct block_device *bdev = bdget_disk(disk, 0);
 
 	if (test_bit(NBD_RT_DISCONNECT_ON_CLOSE, &nbd->config->runtime_flags) &&
-			bdev->bd_openers == 0)
+			disk->part0->bd_openers == 0)
 		nbd_disconnect_and_put(nbd);
-	bdput(bdev);
 
 	nbd_config_put(nbd);
 	nbd_put(nbd);
···
 	if (info->attrs[NBD_ATTR_SIZE_BYTES])
 		bytes = nla_get_u64(info->attrs[NBD_ATTR_SIZE_BYTES]);
 
-	if (info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]) {
+	if (info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES])
 		bsize = nla_get_u64(info->attrs[NBD_ATTR_BLOCK_SIZE_BYTES]);
-		if (!bsize)
-			bsize = NBD_DEF_BLKSIZE;
-		if (!nbd_is_valid_blksize(bsize)) {
-			printk(KERN_ERR "Invalid block size %llu\n", bsize);
-			return -EINVAL;
-		}
-	}
 
 	if (bytes != config->bytesize || bsize != config->blksize)
-		nbd_size_set(nbd, bsize, div64_u64(bytes, bsize));
+		return nbd_set_size(nbd, bytes, bsize);
 	return 0;
 }
 

drivers/block/pktcdvd.c

···
 	}
 
 	set_capacity(pd->disk, lba << 2);
-	set_capacity(pd->bdev->bd_disk, lba << 2);
-	bd_set_nr_sectors(pd->bdev, lba << 2);
+	set_capacity_and_notify(pd->bdev->bd_disk, lba << 2);
 
 	q = bdev_get_queue(pd->bdev);
 	if (write) {
···
 	case CDROM_LAST_WRITTEN:
 	case CDROM_SEND_PACKET:
 	case SCSI_IOCTL_SEND_COMMAND:
-		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
+		if (!bdev->bd_disk->fops->ioctl)
+			ret = -ENOTTY;
+		else
+			ret = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
 		break;
-
 	default:
 		pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
 		ret = -ENOTTY;

drivers/block/rbd.c

···
 	put_device(&rbd_dev->dev);
 }
 
-static int rbd_ioctl_set_ro(struct rbd_device *rbd_dev, unsigned long arg)
+static int rbd_set_read_only(struct block_device *bdev, bool ro)
 {
-	int ro;
-
-	if (get_user(ro, (int __user *)arg))
-		return -EFAULT;
+	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
 
 	/*
 	 * Both images mapped read-only and snapshots can't be marked
···
 		rbd_assert(!rbd_is_snap(rbd_dev));
 	}
 
-	/* Let blkdev_roset() handle it */
-	return -ENOTTY;
+	return 0;
 }
-
-static int rbd_ioctl(struct block_device *bdev, fmode_t mode,
-			unsigned int cmd, unsigned long arg)
-{
-	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
-	int ret;
-
-	switch (cmd) {
-	case BLKROSET:
-		ret = rbd_ioctl_set_ro(rbd_dev, arg);
-		break;
-	default:
-		ret = -ENOTTY;
-	}
-
-	return ret;
-}
-
-#ifdef CONFIG_COMPAT
-static int rbd_compat_ioctl(struct block_device *bdev, fmode_t mode,
-				unsigned int cmd, unsigned long arg)
-{
-	return rbd_ioctl(bdev, mode, cmd, arg);
-}
-#endif /* CONFIG_COMPAT */
 
 static const struct block_device_operations rbd_bd_ops = {
 	.owner			= THIS_MODULE,
 	.open			= rbd_open,
 	.release		= rbd_release,
-	.ioctl			= rbd_ioctl,
-#ifdef CONFIG_COMPAT
-	.compat_ioctl		= rbd_compat_ioctl,
-#endif
+	.set_read_only		= rbd_set_read_only,
 };
 
 /*
···
 	    !test_bit(RBD_DEV_FLAG_REMOVING, &rbd_dev->flags)) {
 		size = (sector_t)rbd_dev->mapping.size / SECTOR_SIZE;
 		dout("setting size to %llu sectors", (unsigned long long)size);
-		set_capacity(rbd_dev->disk, size);
-		revalidate_disk_size(rbd_dev->disk, true);
+		set_capacity_and_notify(rbd_dev->disk, size);
 	}
 }
 

drivers/block/rnbd/rnbd-clt.c

···
 	rnbd_clt_info(dev, "Device size changed from %zu to %zu sectors\n",
 		       dev->nsectors, new_nsectors);
 	dev->nsectors = new_nsectors;
-	set_capacity(dev->gd, dev->nsectors);
-	revalidate_disk_size(dev->gd, true);
+	set_capacity_and_notify(dev->gd, dev->nsectors);
 	return 0;
 }
 

drivers/block/swim.c

···
 	.check_events	 = floppy_check_events,
 };
 
-static struct kobject *floppy_find(dev_t dev, int *part, void *data)
-{
-	struct swim_priv *swd = data;
-	int drive = (*part & 3);
-
-	if (drive >= swd->floppy_count)
-		return NULL;
-
-	*part = 0;
-	return get_disk_and_module(swd->unit[drive].disk);
-}
-
 static int swim_add_floppy(struct swim_priv *swd, enum drive_location location)
 {
 	struct floppy_state *fs = &swd->unit[swd->floppy_count];
···
 		add_disk(swd->unit[drive].disk);
 	}
 
-	blk_register_region(MKDEV(FLOPPY_MAJOR, 0), 256, THIS_MODULE,
-			    floppy_find, NULL, swd);
-
 	return 0;
 
 exit_put_disks:
···
 	struct swim_priv *swd = platform_get_drvdata(dev);
 	int drive;
 	struct resource *res;
-
-	blk_unregister_region(MKDEV(FLOPPY_MAJOR, 0), 256);
 
 	for (drive = 0; drive < swd->floppy_count; drive++) {
 		del_gendisk(swd->unit[drive].disk);

drivers/block/virtio_blk.c

···
 		   cap_str_10,
 		   cap_str_2);
 
-	set_capacity_revalidate_and_notify(vblk->disk, capacity, true);
+	set_capacity_and_notify(vblk->disk, capacity);
 }
 
 static void virtblk_config_changed_work(struct work_struct *work)
···
 	struct virtio_blk *vblk = vdev->priv;
 
 	blk_queue_write_cache(vblk->disk->queue, writeback, false);
-	revalidate_disk_size(vblk->disk, true);
 }
 
 static const char *const virtblk_cache_types[] = {

drivers/block/xen-blkback/common.h

···
 };
 
 
-#define vbd_sz(_v)	((_v)->bdev->bd_part ? \
-			 (_v)->bdev->bd_part->nr_sects : \
-			  get_capacity((_v)->bdev->bd_disk))
+#define vbd_sz(_v)	bdev_nr_sectors((_v)->bdev)
 
 #define xen_blkif_get(_b) (atomic_inc(&(_b)->refcnt))
 #define xen_blkif_put(_b)				\

drivers/block/xen-blkfront.c

···
 	}
 
 	if (info->gd)
-		bdev = bdget_disk(info->gd, 0);
+		bdev = bdgrab(info->gd->part0);
 
 	mutex_unlock(&info->mutex);
 
···
 			return;
 		printk(KERN_INFO "Setting capacity to %Lu\n",
 		       sectors);
-		set_capacity_revalidate_and_notify(info->gd, sectors, true);
+		set_capacity_and_notify(info->gd, sectors);
 
 		return;
 	case BLKIF_STATE_SUSPENDED:
···
 
 	disk = info->gd;
 	if (disk)
-		bdev = bdget_disk(disk, 0);
+		bdev = bdgrab(disk->part0);
 
 	info->xbdev = NULL;
 	mutex_unlock(&info->mutex);
···
 static void blkif_release(struct gendisk *disk, fmode_t mode)
 {
 	struct blkfront_info *info = disk->private_data;
-	struct block_device *bdev;
 	struct xenbus_device *xbdev;
 
 	mutex_lock(&blkfront_mutex);
-
-	bdev = bdget_disk(disk, 0);
-
-	if (!bdev) {
-		WARN(1, "Block device %s yanked out from us!\n", disk->disk_name);
+	if (disk->part0->bd_openers)
 		goto out_mutex;
-	}
-	if (bdev->bd_openers)
-		goto out;
 
 	/*
 	 * Check if we have been instructed to close. We will have
···
 
 	if (xbdev && xbdev->state == XenbusStateClosing) {
 		/* pending switch to state closed */
-		dev_info(disk_to_dev(bdev->bd_disk), "releasing disk\n");
+		dev_info(disk_to_dev(disk), "releasing disk\n");
 		xlvbd_release_gendisk(info);
 		xenbus_frontend_closed(info->xbdev);
  	}
···
 
 	if (!xbdev) {
 		/* sudden device removal */
-		dev_info(disk_to_dev(bdev->bd_disk), "releasing disk\n");
+		dev_info(disk_to_dev(disk), "releasing disk\n");
 		xlvbd_release_gendisk(info);
 		disk->private_data = NULL;
 		free_info(info);
 	}
 
-out:
-	bdput(bdev);
 out_mutex:
 	mutex_unlock(&blkfront_mutex);
 }

drivers/block/z2ram.c

···
 
 #include <linux/zorro.h>
 
-
 #define Z2MINOR_COMBINED      (0)
 #define Z2MINOR_Z2ONLY        (1)
 #define Z2MINOR_CHIPONLY      (2)
···
 #define Z2MINOR_MEMLIST2      (5)
 #define Z2MINOR_MEMLIST3      (6)
 #define Z2MINOR_MEMLIST4      (7)
-#define Z2MINOR_COUNT         (8) /* Move this down when adding a new minor */
+#define Z2MINOR_COUNT         (8)	/* Move this down when adding a new minor */
 
 #define Z2RAM_CHUNK1024       ( Z2RAM_CHUNKSIZE >> 10 )
 
 static DEFINE_MUTEX(z2ram_mutex);
-static u_long *z2ram_map    = NULL;
-static u_long z2ram_size    = 0;
-static int z2_count         = 0;
-static int chip_count       = 0;
-static int list_count       = 0;
-static int current_device   = -1;
+static u_long *z2ram_map = NULL;
+static u_long z2ram_size = 0;
+static int z2_count = 0;
+static int chip_count = 0;
+static int list_count = 0;
+static int current_device = -1;
 
 static DEFINE_SPINLOCK(z2ram_lock);
 
-static struct gendisk *z2ram_gendisk;
+static struct gendisk *z2ram_gendisk[Z2MINOR_COUNT];
 
 static blk_status_t z2_queue_rq(struct blk_mq_hw_ctx *hctx,
 				const struct blk_mq_queue_data *bd)
 {
 	struct request *req = bd->rq;
 	unsigned long start = blk_rq_pos(req) << 9;
-	unsigned long len  = blk_rq_cur_bytes(req);
+	unsigned long len = blk_rq_cur_bytes(req);
 
 	blk_mq_start_request(req);
 
···
 
 		if (len < size)
 			size = len;
-		addr += z2ram_map[ start >> Z2RAM_CHUNKSHIFT ];
+		addr += z2ram_map[start >> Z2RAM_CHUNKSHIFT];
 		if (rq_data_dir(req) == READ)
 			memcpy(buffer, (char *)addr, size);
 		else
···
 	return BLK_STS_OK;
 }
 
-static void
-get_z2ram( void )
+static void get_z2ram(void)
 {
-    int i;
+	int i;
 
-    for ( i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++ )
-    {
-	if ( test_bit( i, zorro_unused_z2ram ) )
-	{
-	    z2_count++;
-	    z2ram_map[z2ram_size++] = (unsigned long)ZTWO_VADDR(Z2RAM_START) +
-				      (i << Z2RAM_CHUNKSHIFT);
-	    clear_bit( i, zorro_unused_z2ram );
+	for (i = 0; i < Z2RAM_SIZE / Z2RAM_CHUNKSIZE; i++) {
+		if (test_bit(i, zorro_unused_z2ram)) {
+			z2_count++;
+			z2ram_map[z2ram_size++] =
+			    (unsigned long)ZTWO_VADDR(Z2RAM_START) +
+			    (i << Z2RAM_CHUNKSHIFT);
+			clear_bit(i, zorro_unused_z2ram);
+		}
 	}
-    }
 
-    return;
+	return;
 }
 
-static void
-get_chipram( void )
+static void get_chipram(void)
 {
 
-    while ( amiga_chip_avail() > ( Z2RAM_CHUNKSIZE * 4 ) )
-    {
-	chip_count++;
-	z2ram_map[ z2ram_size ] =
-	    (u_long)amiga_chip_alloc( Z2RAM_CHUNKSIZE, "z2ram" );
+	while (amiga_chip_avail() > (Z2RAM_CHUNKSIZE * 4)) {
+		chip_count++;
+		z2ram_map[z2ram_size] =
+		    (u_long) amiga_chip_alloc(Z2RAM_CHUNKSIZE, "z2ram");
 
-	if ( z2ram_map[ z2ram_size ] == 0 )
-	{
-	    break;
+		if (z2ram_map[z2ram_size] == 0) {
+			break;
+		}
+
+		z2ram_size++;
 	}
 
-	z2ram_size++;
-    }
-	
-    return;
+	return;
 }
 
 static int z2_open(struct block_device *bdev, fmode_t mode)
 {
-    int device;
-    int max_z2_map = ( Z2RAM_SIZE / Z2RAM_CHUNKSIZE ) *
-	sizeof( z2ram_map[0] );
-    int max_chip_map = ( amiga_chip_size / Z2RAM_CHUNKSIZE ) *
-	sizeof( z2ram_map[0] );
-    int rc = -ENOMEM;
+	int device;
+	int max_z2_map = (Z2RAM_SIZE / Z2RAM_CHUNKSIZE) * sizeof(z2ram_map[0]);
+	int max_chip_map = (amiga_chip_size / Z2RAM_CHUNKSIZE) *
+	    sizeof(z2ram_map[0]);
+	int rc = -ENOMEM;
 
-    device = MINOR(bdev->bd_dev);
+	device = MINOR(bdev->bd_dev);
 
-    mutex_lock(&z2ram_mutex);
-    if ( current_device != -1 && current_device != device )
-    {
-	rc = -EBUSY;
-	goto err_out;
-    }
+	mutex_lock(&z2ram_mutex);
+	if (current_device != -1 && current_device != device) {
+		rc = -EBUSY;
+		goto err_out;
+	}
 
-    if ( current_device == -1 )
-    {
-	z2_count   = 0;
-	chip_count = 0;
-	list_count = 0;
-	z2ram_size = 0;
+	if (current_device == -1) {
+		z2_count = 0;
+		chip_count = 0;
+		list_count = 0;
+		z2ram_size = 0;
 
-	/* Use a specific list entry. */
-	if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
-		int index = device - Z2MINOR_MEMLIST1 + 1;
-		unsigned long size, paddr, vaddr;
+		/* Use a specific list entry. */
+		if (device >= Z2MINOR_MEMLIST1 && device <= Z2MINOR_MEMLIST4) {
+			int index = device - Z2MINOR_MEMLIST1 + 1;
+			unsigned long size, paddr, vaddr;
 
-		if (index >= m68k_realnum_memory) {
-			printk( KERN_ERR DEVICE_NAME
-				": no such entry in z2ram_map\n" );
-		        goto err_out;
-		}
+			if (index >= m68k_realnum_memory) {
+				printk(KERN_ERR DEVICE_NAME
+				       ": no such entry in z2ram_map\n");
+				goto err_out;
+			}
 
-		paddr = m68k_memory[index].addr;
-		size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE-1);
+			paddr = m68k_memory[index].addr;
+			size = m68k_memory[index].size & ~(Z2RAM_CHUNKSIZE - 1);
 
 #ifdef __powerpc__
-		/* FIXME: ioremap doesn't build correct memory tables. */
-		{
-			vfree(vmalloc (size));
-		}
+			/* FIXME: ioremap doesn't build correct memory tables. */
+			{
+				vfree(vmalloc(size));
+			}
 
-		vaddr = (unsigned long)ioremap_wt(paddr, size);
+			vaddr = (unsigned long)ioremap_wt(paddr, size);
 
 #else
-		vaddr = (unsigned long)z_remap_nocache_nonser(paddr, size);
+			vaddr =
+			    (unsigned long)z_remap_nocache_nonser(paddr, size);
 #endif
-		z2ram_map = 
-			kmalloc_array(size / Z2RAM_CHUNKSIZE,
-                                      sizeof(z2ram_map[0]),
-                                      GFP_KERNEL);
-		if ( z2ram_map == NULL )
-		{
-		    printk( KERN_ERR DEVICE_NAME
-			": cannot get mem for z2ram_map\n" );
-		    goto err_out;
+			z2ram_map =
+			    kmalloc_array(size / Z2RAM_CHUNKSIZE,
+					  sizeof(z2ram_map[0]), GFP_KERNEL);
+			if (z2ram_map == NULL) {
+				printk(KERN_ERR DEVICE_NAME
+				       ": cannot get mem for z2ram_map\n");
+				goto err_out;
+			}
+
+			while (size) {
+				z2ram_map[z2ram_size++] = vaddr;
+				size -= Z2RAM_CHUNKSIZE;
+				vaddr += Z2RAM_CHUNKSIZE;
+				list_count++;
+			}
+
+			if (z2ram_size != 0)
+				printk(KERN_INFO DEVICE_NAME
+				       ": using %iK List Entry %d Memory\n",
+				       list_count * Z2RAM_CHUNK1024, index);
+		} else
+			switch (device) {
+			case Z2MINOR_COMBINED:
+
+				z2ram_map =
+				    kmalloc(max_z2_map + max_chip_map,
+					    GFP_KERNEL);
+				if (z2ram_map == NULL) {
+					printk(KERN_ERR DEVICE_NAME
+					       ": cannot get mem for z2ram_map\n");
+					goto err_out;
+				}
+
+				get_z2ram();
+				get_chipram();
+
+				if (z2ram_size != 0)
+					printk(KERN_INFO DEVICE_NAME
+					       ": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
+					       z2_count * Z2RAM_CHUNK1024,
+					       chip_count * Z2RAM_CHUNK1024,
+					       (z2_count +
+						chip_count) * Z2RAM_CHUNK1024);
+
+				break;
+
+			case Z2MINOR_Z2ONLY:
+				z2ram_map = kmalloc(max_z2_map, GFP_KERNEL);
+				if (z2ram_map == NULL) {
+					printk(KERN_ERR DEVICE_NAME
+					       ": cannot get mem for z2ram_map\n");
+					goto err_out;
+				}
+
+				get_z2ram();
+
+				if (z2ram_size != 0)
+					printk(KERN_INFO DEVICE_NAME
+					       ": using %iK of Zorro II RAM\n",
+					       z2_count * Z2RAM_CHUNK1024);
+
+				break;
+
+			case Z2MINOR_CHIPONLY:
+				z2ram_map = kmalloc(max_chip_map, GFP_KERNEL);
+				if (z2ram_map == NULL) {
+					printk(KERN_ERR DEVICE_NAME
+					       ": cannot get mem for z2ram_map\n");
+					goto err_out;
+				}
+
+				get_chipram();
+
+				if (z2ram_size != 0)
+					printk(KERN_INFO DEVICE_NAME
+					       ": using %iK Chip RAM\n",
+					       chip_count * Z2RAM_CHUNK1024);
+
+				break;
+
+			default:
+				rc = -ENODEV;
+				goto err_out;
+
+				break;
+			}
+
+		if (z2ram_size == 0) {
+			printk(KERN_NOTICE DEVICE_NAME
+			       ": no unused ZII/Chip RAM found\n");
+			goto err_out_kfree;
 		}
 
-		while (size) {
-			z2ram_map[ z2ram_size++ ] = vaddr;
-			size -= Z2RAM_CHUNKSIZE;
-			vaddr += Z2RAM_CHUNKSIZE;
-			list_count++;
-		}
-
-		if ( z2ram_size != 0 )
-		    printk( KERN_INFO DEVICE_NAME
-			": using %iK List Entry %d Memory\n",
-			list_count * Z2RAM_CHUNK1024, index );
-	} else
-
-	switch ( device )
-	{
-	    case Z2MINOR_COMBINED:
-
-		z2ram_map = kmalloc( max_z2_map + max_chip_map, GFP_KERNEL );
-		if ( z2ram_map == NULL )
-		{
-		    printk( KERN_ERR DEVICE_NAME
-			": cannot get mem for z2ram_map\n" );
-		    goto err_out;
-		}
-
-		get_z2ram();
-		get_chipram();
-
-		if ( z2ram_size != 0 )
-		    printk( KERN_INFO DEVICE_NAME 
-			": using %iK Zorro II RAM and %iK Chip RAM (Total %dK)\n",
-			z2_count * Z2RAM_CHUNK1024,
-			chip_count * Z2RAM_CHUNK1024,
-			( z2_count + chip_count ) * Z2RAM_CHUNK1024 );
-
-	    break;
-
-    	    case Z2MINOR_Z2ONLY:
-		z2ram_map = kmalloc( max_z2_map, GFP_KERNEL );
-		if ( z2ram_map == NULL )
-		{
-		    printk( KERN_ERR DEVICE_NAME
-			": cannot get mem for z2ram_map\n" );
-		    goto err_out;
-		}
-
-		get_z2ram();
-
-		if ( z2ram_size != 0 )
-		    printk( KERN_INFO DEVICE_NAME 
-			": using %iK of Zorro II RAM\n",
-			z2_count * Z2RAM_CHUNK1024 );
-
-	    break;
-
-	    case Z2MINOR_CHIPONLY:
-		z2ram_map = kmalloc( max_chip_map, GFP_KERNEL );
-		if ( z2ram_map == NULL )
-		{
-		    printk( KERN_ERR DEVICE_NAME
-			": cannot get mem for z2ram_map\n" );
-		    goto err_out;
-		}
-
-		get_chipram();
-
-		if ( z2ram_size != 0 )
-		    printk( KERN_INFO DEVICE_NAME 
-			": using %iK Chip RAM\n",
-			chip_count * Z2RAM_CHUNK1024 );
-		    
-	    break;
-
-	    default:
-		rc = -ENODEV;
-		goto err_out;
-	
-	    break;
+		current_device = device;
+		z2ram_size <<= Z2RAM_CHUNKSHIFT;
+		set_capacity(z2ram_gendisk[device], z2ram_size >> 9);
 	}
 
-	if ( z2ram_size == 0 )
-	{
-	    printk( KERN_NOTICE DEVICE_NAME
-		": no unused ZII/Chip RAM found\n" );
-	    goto err_out_kfree;
-	}
-
-	current_device = device;
-	z2ram_size <<= Z2RAM_CHUNKSHIFT;
-	set_capacity(z2ram_gendisk, z2ram_size >> 9);
-    }
-
-    mutex_unlock(&z2ram_mutex);
-    return 0;
+	mutex_unlock(&z2ram_mutex);
+	return 0;
 
 err_out_kfree:
-    kfree(z2ram_map);
+	kfree(z2ram_map);
 err_out:
-    mutex_unlock(&z2ram_mutex);
-    return rc;
+	mutex_unlock(&z2ram_mutex);
+	return rc;
 }
 
-static void
-z2_release(struct gendisk *disk, fmode_t mode)
+static void z2_release(struct gendisk *disk, fmode_t mode)
 {
-    mutex_lock(&z2ram_mutex);
-    if ( current_device == -1 ) {
-    	mutex_unlock(&z2ram_mutex);
-    	return;
-    }
-    mutex_unlock(&z2ram_mutex);
-    /*
-     * FIXME: unmap memory
-     */
+	mutex_lock(&z2ram_mutex);
+	if (current_device == -1) {
+		mutex_unlock(&z2ram_mutex);
+		return;
+	}
+	mutex_unlock(&z2ram_mutex);
+	/*
+	 * FIXME: unmap memory
+	 */
 }
 
-static const struct block_device_operations z2_fops =
-{
-	.owner		= THIS_MODULE,
-	.open		= z2_open,
-	.release	= z2_release,
+static const struct block_device_operations z2_fops = {
+	.owner = THIS_MODULE,
+	.open = z2_open,
+	.release = z2_release,
 };
 
-static struct kobject *z2_find(dev_t dev, int *part, void *data)
-{
-	*part = 0;
-	return get_disk_and_module(z2ram_gendisk);
-}
-
-static struct request_queue *z2_queue;
 static struct blk_mq_tag_set tag_set;
 
 static const struct blk_mq_ops z2_mq_ops = {
-	.queue_rq	= z2_queue_rq,
+	.queue_rq = z2_queue_rq,
 };
 
-static int __init 
-z2_init(void)
+static int z2ram_register_disk(int minor)
 {
-    int ret;
+	struct request_queue *q;
+	struct gendisk *disk;
 
-    if (!MACH_IS_AMIGA)
-	return -ENODEV;
+	disk = alloc_disk(1);
+	if (!disk)
+		return -ENOMEM;
 
-    ret = -EBUSY;
-    if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
-	goto err;
+	q = blk_mq_init_queue(&tag_set);
+	if (IS_ERR(q)) {
+		put_disk(disk);
+		return PTR_ERR(q);
+	}
 
-    ret = -ENOMEM;
-    z2ram_gendisk = alloc_disk(1);
-    if (!z2ram_gendisk)
-	goto out_disk;
+	disk->major = Z2RAM_MAJOR;
+	disk->first_minor = minor;
+	disk->fops = &z2_fops;
+	if (minor)
+		sprintf(disk->disk_name, "z2ram%d", minor);
+	else
+		sprintf(disk->disk_name, "z2ram");
+	disk->queue = q;
 
-    z2_queue = blk_mq_init_sq_queue(&tag_set, &z2_mq_ops, 16,
-					BLK_MQ_F_SHOULD_MERGE);
-    if (IS_ERR(z2_queue)) {
-	ret = PTR_ERR(z2_queue);
-	z2_queue = NULL;
-	goto out_queue;
-    }
+	z2ram_gendisk[minor] = disk;
+	add_disk(disk);
+	return 0;
+}
 
-    z2ram_gendisk->major = Z2RAM_MAJOR;
-    z2ram_gendisk->first_minor = 0;
-    z2ram_gendisk->fops = &z2_fops;
-    sprintf(z2ram_gendisk->disk_name, "z2ram");
+static int __init z2_init(void)
+{
+	int ret, i;
 
-    z2ram_gendisk->queue = z2_queue;
-    add_disk(z2ram_gendisk);
-    blk_register_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT, THIS_MODULE,
-				z2_find, NULL, NULL);
+	if (!MACH_IS_AMIGA)
+		return -ENODEV;
 
-    return 0;
+	if (register_blkdev(Z2RAM_MAJOR, DEVICE_NAME))
+		return -EBUSY;
 
-out_queue:
-    put_disk(z2ram_gendisk);
-out_disk:
-    unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
-err:
-    return ret;
+	tag_set.ops = &z2_mq_ops;
+	tag_set.nr_hw_queues = 1;
+	tag_set.nr_maps = 1;
+	tag_set.queue_depth = 16;
+	tag_set.numa_node = NUMA_NO_NODE;
+	tag_set.flags = BLK_MQ_F_SHOULD_MERGE;
+	ret = blk_mq_alloc_tag_set(&tag_set);
+	if (ret)
+		goto out_unregister_blkdev;
+
+	for (i = 0; i < Z2MINOR_COUNT; i++) {
+		ret = z2ram_register_disk(i);
+		if (ret && i == 0)
+			goto out_free_tagset;
+	}
+
+	return 0;
+
+out_free_tagset:
+	blk_mq_free_tag_set(&tag_set);
+out_unregister_blkdev:
+	unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
+	return ret;
 }
 
 static void __exit z2_exit(void)
 {
-    int i, j;
-    blk_unregister_region(MKDEV(Z2RAM_MAJOR, 0), Z2MINOR_COUNT);
-    unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
-    del_gendisk(z2ram_gendisk);
-    put_disk(z2ram_gendisk);
-    blk_cleanup_queue(z2_queue);
-    blk_mq_free_tag_set(&tag_set);
+	int i, j;
 
-    if ( current_device != -1 )
-    {
-	i = 0;
+	unregister_blkdev(Z2RAM_MAJOR, DEVICE_NAME);
 
-	for ( j = 0 ; j < z2_count; j++ )
-	{
-	    set_bit( i++, zorro_unused_z2ram ); 
+	for (i = 0; i < Z2MINOR_COUNT; i++) {
+		del_gendisk(z2ram_gendisk[i]);
+		blk_cleanup_queue(z2ram_gendisk[i]->queue);
+		put_disk(z2ram_gendisk[i]);
+	}
+	blk_mq_free_tag_set(&tag_set);
+
+	if (current_device != -1) {
+		i = 0;
+
+		for (j = 0; j < z2_count; j++) {
+			set_bit(i++, zorro_unused_z2ram);
+		}
+
+		for (j = 0; j < chip_count; j++) {
+			if (z2ram_map[i]) {
+				amiga_chip_free((void *)z2ram_map[i++]);
+			}
+		}
+
+		if (z2ram_map != NULL) {
+			kfree(z2ram_map);
+		}
 	}
 
-	for ( j = 0 ; j < chip_count; j++ )
-	{
-	    if ( z2ram_map[ i ] )
-	    {
-		amiga_chip_free( (void *) z2ram_map[ i++ ] );
-	    }
-	}
-
-	if ( z2ram_map != NULL )
-	{
-	    kfree( z2ram_map );
-	}
-    }
-
-    return;
-} 
+	return;
+}
 
 module_init(z2_init);
 module_exit(z2_exit);

drivers/block/zram/zram_drv.c

···
 		return;
 
 	bdev = zram->bdev;
-	if (zram->old_block_size)
-		set_blocksize(bdev, zram->old_block_size);
 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 	/* hope filp_close flush all of IO */
 	filp_close(zram->backing_dev, NULL);
 	zram->backing_dev = NULL;
-	zram->old_block_size = 0;
 	zram->bdev = NULL;
 	zram->disk->fops = &zram_devops;
 	kvfree(zram->bitmap);
···
 	struct file *backing_dev = NULL;
 	struct inode *inode;
 	struct address_space *mapping;
-	unsigned int bitmap_sz, old_block_size = 0;
+	unsigned int bitmap_sz;
 	unsigned long nr_pages, *bitmap = NULL;
 	struct block_device *bdev = NULL;
 	int err;
···
 		goto out;
 	}
 
-	old_block_size = block_size(bdev);
-	err = set_blocksize(bdev, PAGE_SIZE);
-	if (err)
-		goto out;
-
 	reset_bdev(zram);
 
-	zram->old_block_size = old_block_size;
 	zram->bdev = bdev;
 	zram->backing_dev = backing_dev;
 	zram->bitmap = bitmap;
···
 	disksize = zram->disksize;
 	zram->disksize = 0;
 
-	set_capacity(zram->disk, 0);
-	part_stat_set_all(&zram->disk->part0, 0);
+	set_capacity_and_notify(zram->disk, 0);
+	part_stat_set_all(zram->disk->part0, 0);
 
 	up_write(&zram->init_lock);
 	/* I/O operation under all of CPU are done so let's free */
···
 
 	zram->comp = comp;
 	zram->disksize = disksize;
-	set_capacity(zram->disk, zram->disksize >> SECTOR_SHIFT);
-
-	revalidate_disk_size(zram->disk, true);
+	set_capacity_and_notify(zram->disk, zram->disksize >> SECTOR_SHIFT);
 	up_write(&zram->init_lock);
 
 	return len;
···
 		return -EINVAL;
 
 	zram = dev_to_zram(dev);
-	bdev = bdget_disk(zram->disk, 0);
-	if (!bdev)
-		return -ENOMEM;
+	bdev = zram->disk->part0;
 
 	mutex_lock(&bdev->bd_mutex);
 	/* Do not reset an active device or claimed device */
 	if (bdev->bd_openers || zram->claim) {
 		mutex_unlock(&bdev->bd_mutex);
-		bdput(bdev);
 		return -EBUSY;
 	}
 
···
 	/* Make sure all the pending I/O are finished */
 	fsync_bdev(bdev);
 	zram_reset_device(zram);
-	revalidate_disk_size(zram->disk, true);
-	bdput(bdev);
 
 	mutex_lock(&bdev->bd_mutex);
 	zram->claim = false;
···
 
 static int zram_remove(struct zram *zram)
 {
-	struct block_device *bdev;
-
-	bdev = bdget_disk(zram->disk, 0);
-	if (!bdev)
-		return -ENOMEM;
+	struct block_device *bdev = zram->disk->part0;
 
 	mutex_lock(&bdev->bd_mutex);
 	if (bdev->bd_openers || zram->claim) {
 		mutex_unlock(&bdev->bd_mutex);
-		bdput(bdev);
 		return -EBUSY;
 	}
 
···
 	/* Make sure all the pending I/O are finished */
 	fsync_bdev(bdev);
 	zram_reset_device(zram);
-	bdput(bdev);
 
 	pr_info("Removed device: %s\n", zram->disk->disk_name);
 

drivers/block/zram/zram_drv.h

···
 	bool wb_limit_enable;
 	u64 bd_wb_limit;
 	struct block_device *bdev;
-	unsigned int old_block_size;
 	unsigned long *bitmap;
 	unsigned long nr_pages;
 #endif

drivers/ide/ide-probe.c

···
 	return 1;
 }
 
-static int ata_lock(dev_t dev, void *data)
+static void ata_probe(dev_t dev)
 {
-	/* FIXME: we want to pin hwif down */
-	return 0;
+	request_module("ide-disk");
+	request_module("ide-cd");
+	request_module("ide-tape");
+	request_module("ide-floppy");
 }
-
-static struct kobject *ata_probe(dev_t dev, int *part, void *data)
-{
-	ide_hwif_t *hwif = data;
-	int unit = *part >> PARTN_BITS;
-	ide_drive_t *drive = hwif->devices[unit];
-
-	if ((drive->dev_flags & IDE_DFLAG_PRESENT) == 0)
-		return NULL;
-
-	if (drive->media == ide_disk)
-		request_module("ide-disk");
-	if (drive->media == ide_cdrom || drive->media == ide_optical)
-		request_module("ide-cd");
-	if (drive->media == ide_tape)
-		request_module("ide-tape");
-	if (drive->media == ide_floppy)
-		request_module("ide-floppy");
-
-	return NULL;
-}
-
-static struct kobject *exact_match(dev_t dev, int *part, void *data)
-{
-	struct gendisk *p = data;
-	*part &= (1 << PARTN_BITS) - 1;
-	return &disk_to_dev(p)->kobj;
-}
-
-static int exact_lock(dev_t dev, void *data)
-{
-	struct gendisk *p = data;
-
-	if (!get_disk_and_module(p))
-		return -1;
-	return 0;
-}
-
-void ide_register_region(struct gendisk *disk)
-{
-	blk_register_region(MKDEV(disk->major, disk->first_minor),
-			    disk->minors, NULL, exact_match, exact_lock, disk);
-}
-
-EXPORT_SYMBOL_GPL(ide_register_region);
-
-void ide_unregister_region(struct gendisk *disk)
-{
-	blk_unregister_region(MKDEV(disk->major, disk->first_minor),
-			      disk->minors);
-}
-
-EXPORT_SYMBOL_GPL(ide_unregister_region);
 
 void ide_init_disk(struct gendisk *disk, ide_drive_t *drive)
 {
···
 		return 0;
 	}
 
-	if (register_blkdev(hwif->major, hwif->name))
+	if (__register_blkdev(hwif->major, hwif->name, ata_probe))
 		return 0;
 
 	if (!hwif->sg_max_nents)
···
 		goto out;
 	}
 
-	blk_register_region(MKDEV(hwif->major, 0), MAX_DRIVES << PARTN_BITS,
-			    THIS_MODULE, ata_probe, ata_lock, hwif);
 	return 1;
 
 out:
···
 	/*
 	 * Remove us from the kernel's knowledge
 	 */
-	blk_unregister_region(MKDEV(hwif->major, 0), MAX_DRIVES<<PARTN_BITS);
 	kfree(hwif->sg_table);
 	unregister_blkdev(hwif->major, hwif->name);
 

drivers/ide/ide-tape.c

···
 
 	ide_proc_unregister_driver(drive, tape->driver);
 	device_del(&tape->dev);
-	ide_unregister_region(tape->disk);
 
 	mutex_lock(&idetape_ref_mutex);
 	put_device(&tape->dev);
···
 		      "n%s", tape->name);
 
 	g->fops = &idetape_block_ops;
-	ide_register_region(g);
 
 	return 0;
 

drivers/md/bcache/request.c

···
 	unsigned int		read_dirty_data:1;
 	unsigned int		cache_missed:1;
 
-	struct hd_struct	*part;
+	struct block_device	*part;
 	unsigned long		start_time;
 
 	struct btree_op		op;
···
 	unsigned long		start_time;
 	bio_end_io_t		*bi_end_io;
 	void			*bi_private;
-	struct hd_struct	*part;
+	struct block_device	*part;
 };
 
 static void detached_dev_end_io(struct bio *bio)
···
 
 	if (dc->io_disable)
 		return -EIO;
-
-	return __blkdev_driver_ioctl(dc->bdev, mode, cmd, arg);
+	if (!dc->bdev->bd_disk->fops->ioctl)
+		return -ENOTTY;
+	return dc->bdev->bd_disk->fops->ioctl(dc->bdev, mode, cmd, arg);
 }
 
 void bch_cached_dev_request_init(struct cached_dev *dc)

drivers/md/bcache/super.c

···
 			q->limits.raid_partial_stripes_expensive;
 
 	ret = bcache_device_init(&dc->disk, block_size,
-			 dc->bdev->bd_part->nr_sects - dc->sb.data_offset,
+			 bdev_nr_sectors(dc->bdev) - dc->sb.data_offset,
 			 dc->bdev, &bcache_cached_ops);
 	if (ret)
 		return ret;
···
 		goto err;
 
 	err = "error creating kobject";
-	if (kobject_add(&dc->disk.kobj, &part_to_dev(bdev->bd_part)->kobj,
-			"bcache"))
+	if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache"))
 		goto err;
 	if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
 		goto err;
···
 		goto err;
 	}
 
-	if (kobject_add(&ca->kobj,
-			&part_to_dev(bdev->bd_part)->kobj,
-			"bcache")) {
+	if (kobject_add(&ca->kobj, bdev_kobj(bdev), "bcache")) {
 		err = "error calling kobject_add";
 		ret = -ENOMEM;
 		goto out;
···
 kobj_attribute_write(register_quiet,	register_bcache);
 kobj_attribute_write(pendings_cleanup,	bch_pending_bdevs_cleanup);
 
-static bool bch_is_open_backing(struct block_device *bdev)
+static bool bch_is_open_backing(dev_t dev)
 {
 	struct cache_set *c, *tc;
 	struct cached_dev *dc, *t;
 
 	list_for_each_entry_safe(c, tc, &bch_cache_sets, list)
 		list_for_each_entry_safe(dc, t, &c->cached_devs, list)
-			if (dc->bdev == bdev)
+			if (dc->bdev->bd_dev == dev)
 				return true;
 	list_for_each_entry_safe(dc, t, &uncached_devices, list)
-		if (dc->bdev == bdev)
+		if (dc->bdev->bd_dev == dev)
 			return true;
 	return false;
 }
 
-static bool bch_is_open_cache(struct block_device *bdev)
+static bool bch_is_open_cache(dev_t dev)
 {
 	struct cache_set *c, *tc;
 
 	list_for_each_entry_safe(c, tc, &bch_cache_sets, list) {
 		struct cache *ca = c->cache;
 
-		if (ca->bdev == bdev)
+		if (ca->bdev->bd_dev == dev)
 			return true;
 	}
 
 	return false;
 }
 
-static bool bch_is_open(struct block_device *bdev)
+static bool bch_is_open(dev_t dev)
 {
-	return bch_is_open_cache(bdev) || bch_is_open_backing(bdev);
+	return bch_is_open_cache(dev) || bch_is_open_backing(dev);
 }
 
 struct async_reg_args {
···
 				  sb);
 	if (IS_ERR(bdev)) {
 		if (bdev == ERR_PTR(-EBUSY)) {
-			bdev = lookup_bdev(strim(path));
+			dev_t dev;
+
 			mutex_lock(&bch_register_lock);
-			if (!IS_ERR(bdev) && bch_is_open(bdev))
+			if (lookup_bdev(strim(path), &dev) == 0 &&
+			    bch_is_open(dev))
 				err = "device already registered";
 			else
 				err = "device busy";

drivers/md/dm-core.h

···
 	 */
 	struct workqueue_struct *wq;
 
-	/*
-	 * freeze/thaw support require holding onto a super block
-	 */
-	struct super_block *frozen_sb;
-
 	/* forced geometry settings */
 	struct hd_geometry geometry;
 
 	/* kobject and completion */
 	struct dm_kobject_holder kobj_holder;
-
-	struct block_device *bdev;
 
 	struct dm_stats stats;
 

drivers/md/dm-raid.c

···
 {
 	struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
 
-	set_capacity(gendisk, rs->md.array_sectors);
-	revalidate_disk_size(gendisk, true);
+	set_capacity_and_notify(gendisk, rs->md.array_sectors);
 }
 
 /*

drivers/md/dm-rq.c

···
 		}
 
 		/* The target has remapped the I/O so dispatch it */
-		trace_block_rq_remap(clone->q, clone, disk_devt(dm_disk(md)),
+		trace_block_rq_remap(clone, disk_devt(dm_disk(md)),
 				     blk_rq_pos(rq));
 		ret = dm_dispatch_clone_request(clone, rq);
 		if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE) {

drivers/md/dm-table.c

···
 dev_t dm_get_dev_t(const char *path)
 {
 	dev_t dev;
-	struct block_device *bdev;
 
-	bdev = lookup_bdev(path);
-	if (IS_ERR(bdev))
+	if (lookup_bdev(path, &dev))
 		dev = name_to_dev_t(path);
-	else {
-		dev = bdev->bd_dev;
-		bdput(bdev);
-	}
-
 	return dev;
 }
 EXPORT_SYMBOL_GPL(dm_get_dev_t);

drivers/md/dm.c

···
 		}
 	}
 
-	r =  __blkdev_driver_ioctl(bdev, mode, cmd, arg);
+	if (!bdev->bd_disk->fops->ioctl)
+		r = -ENOTTY;
+	else
+		r = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
 out:
 	dm_unprepare_ioctl(md, srcu_idx);
 	return r;
···
 		break;
 	case DM_MAPIO_REMAPPED:
 		/* the bio has been remapped so dispatch it */
-		trace_block_bio_remap(clone->bi_disk->queue, clone,
-				      bio_dev(io->orig_bio), sector);
+		trace_block_bio_remap(clone, bio_dev(io->orig_bio), sector);
 		ret = submit_bio_noacct(clone);
 		break;
 	case DM_MAPIO_KILL:
···
 	 */
 	bio_init(&flush_bio, NULL, 0);
 	flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC;
+	flush_bio.bi_disk = ci->io->md->disk;
+	bio_associate_blkg(&flush_bio);
+
 	ci->bio = &flush_bio;
 	ci->sector_count = 0;
-
-	/*
-	 * Empty flush uses a statically initialized bio, as the base for
-	 * cloning.  However, blkg association requires that a bdev is
-	 * associated with a gendisk, which doesn't happen until the bdev is
-	 * opened.  So, blkg association is done at issue time of the flush
-	 * rather than when the device is created in alloc_dev().
-	 */
-	bio_set_dev(ci->bio, ci->io->md->bdev);
 
 	BUG_ON(bio_has_data(ci->bio));
 	while ((ti = dm_table_get_target(ci->map, target_nr++)))
···
 				 * (by eliminating DM's splitting and just using bio_split)
 				 */
 				part_stat_lock();
-				__dm_part_stat_sub(&dm_disk(md)->part0,
+				__dm_part_stat_sub(dm_disk(md)->part0,
 						   sectors[op_stat_group(bio_op(bio))], ci.sector_count);
 				part_stat_unlock();
 
 				bio_chain(b, bio);
-				trace_block_split(md->queue, b, bio->bi_iter.bi_sector);
+				trace_block_split(b, bio->bi_iter.bi_sector);
 				ret = submit_bio_noacct(bio);
 				break;
 			}
···
 
 	cleanup_srcu_struct(&md->io_barrier);
 
-	if (md->bdev) {
-		bdput(md->bdev);
-		md->bdev = NULL;
-	}
-
 	mutex_destroy(&md->suspend_lock);
 	mutex_destroy(&md->type_lock);
 	mutex_destroy(&md->table_devices_lock);
···
 
 	md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0);
 	if (!md->wq)
-		goto bad;
-
-	md->bdev = bdget_disk(md->disk, 0);
-	if (!md->bdev)
 		goto bad;
 
 	dm_stats_init(&md->stats);
···
 	if (size != dm_get_size(md))
 		memset(&md->geometry, 0, sizeof(md->geometry));
 
-	set_capacity(md->disk, size);
-	bd_set_nr_sectors(md->bdev, size);
+	set_capacity_and_notify(md->disk, size);
 
 	dm_table_event_callback(t, event_callback, md);
 
···
 static bool md_in_flight_bios(struct mapped_device *md)
 {
 	int cpu;
-	struct hd_struct *part = &dm_disk(md)->part0;
+	struct block_device *part = dm_disk(md)->part0;
 	long sum = 0;
 
 	for_each_possible_cpu(cpu) {
···
 {
 	int r;
 
-	WARN_ON(md->frozen_sb);
+	WARN_ON(test_bit(DMF_FROZEN, &md->flags));
 
-	md->frozen_sb = freeze_bdev(md->bdev);
-	if (IS_ERR(md->frozen_sb)) {
-		r = PTR_ERR(md->frozen_sb);
-		md->frozen_sb = NULL;
-		return r;
-	}
-
-	set_bit(DMF_FROZEN, &md->flags);
-
-	return 0;
+	r = freeze_bdev(md->disk->part0);
+	if (!r)
+		set_bit(DMF_FROZEN, &md->flags);
+	return r;
 }
 
 static void unlock_fs(struct mapped_device *md)
 {
 	if (!test_bit(DMF_FROZEN, &md->flags))
 		return;
-
-	thaw_bdev(md->bdev, md->frozen_sb);
-	md->frozen_sb = NULL;
+	thaw_bdev(md->disk->part0);
 	clear_bit(DMF_FROZEN, &md->flags);
 }
 

drivers/md/md-cluster.c

···
 		process_metadata_update(mddev, msg);
 		break;
 	case CHANGE_CAPACITY:
-		set_capacity(mddev->gendisk, mddev->array_sectors);
-		revalidate_disk_size(mddev->gendisk, true);
+		set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 		break;
 	case RESYNCING:
 		set_bit(MD_RESYNCING_REMOTE, &mddev->recovery);
···
 		if (ret)
 			pr_err("%s:%d: failed to send CHANGE_CAPACITY msg\n",
 			       __func__, __LINE__);
-		set_capacity(mddev->gendisk, mddev->array_sectors);
-		revalidate_disk_size(mddev->gendisk, true);
+		set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 	} else {
 		/* revert to previous sectors */
 		ret = mddev->pers->resize(mddev, old_dev_sectors);
-		if (!ret)
-			revalidate_disk_size(mddev->gendisk, true);
 		ret = __sendmsg(cinfo, &cmsg);
 		if (ret)
 			pr_err("%s:%d: failed to send METADATA_UPDATED msg\n",

drivers/md/md-linear.c

···
 		"copied raid_disks doesn't match mddev->raid_disks");
 	rcu_assign_pointer(mddev->private, newconf);
 	md_set_array_sectors(mddev, linear_size(mddev, 0, 0));
-	set_capacity(mddev->gendisk, mddev->array_sectors);
+	set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 	mddev_resume(mddev);
-	revalidate_disk_size(mddev->gendisk, true);
 	kfree_rcu(oldconf, rcu);
 	return 0;
 }
···
 		bio_endio(bio);
 	} else {
 		if (mddev->gendisk)
-			trace_block_bio_remap(bio->bi_disk->queue,
-					      bio, disk_devt(mddev->gendisk),
+			trace_block_bio_remap(bio, disk_devt(mddev->gendisk),
 					      bio_sector);
 		mddev_check_writesame(mddev, bio);
 		mddev_check_write_zeroes(mddev, bio);

drivers/md/md.c

···
 	bio_end_io_t *orig_bi_end_io;
 	void *orig_bi_private;
 	unsigned long start_time;
-	struct hd_struct *part;
+	struct block_device *part;
 };
 
 static void md_end_io(struct bio *bio)
···
 static int bind_rdev_to_array(struct md_rdev *rdev, struct mddev *mddev)
 {
 	char b[BDEVNAME_SIZE];
-	struct kobject *ko;
 	int err;
 
 	/* prevent duplicates */
···
 	if ((err = kobject_add(&rdev->kobj, &mddev->kobj, "dev-%s", b)))
 		goto fail;
 
-	ko = &part_to_dev(rdev->bdev->bd_part)->kobj;
 	/* failure here is OK */
-	err = sysfs_create_link(&rdev->kobj, ko, "block");
+	err = sysfs_create_link(&rdev->kobj, bdev_kobj(rdev->bdev), "block");
 	rdev->sysfs_state = sysfs_get_dirent_safe(rdev->kobj.sd, "state");
 	rdev->sysfs_unack_badblocks =
 		sysfs_get_dirent_safe(rdev->kobj.sd, "unacknowledged_bad_blocks");
···
 
 	if (!err) {
 		mddev->array_sectors = sectors;
-		if (mddev->pers) {
-			set_capacity(mddev->gendisk, mddev->array_sectors);
-			revalidate_disk_size(mddev->gendisk, true);
-		}
+		if (mddev->pers)
+			set_capacity_and_notify(mddev->gendisk,
+						mddev->array_sectors);
 	}
 	mddev_unlock(mddev);
 	return err ?: len;
···
 	return error;
 }
 
-static struct kobject *md_probe(dev_t dev, int *part, void *data)
+static void md_probe(dev_t dev)
 {
+	if (MAJOR(dev) == MD_MAJOR && MINOR(dev) >= 512)
+		return;
 	if (create_on_open)
 		md_alloc(dev, NULL);
-	return NULL;
 }
 
 static int add_named_array(const char *val, const struct kernel_param *kp)
···
 	md_wakeup_thread(mddev->thread);
 	md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
 
-	set_capacity(mddev->gendisk, mddev->array_sectors);
-	revalidate_disk_size(mddev->gendisk, true);
+	set_capacity_and_notify(mddev->gendisk, mddev->array_sectors);
 	clear_bit(MD_NOT_READY, &mddev->flags);
 	mddev->changed = 1;
 	kobject_uevent(&disk_to_dev(mddev->gendisk)->kobj, KOBJ_CHANGE);
···
 			if (rdev->raid_disk >= 0)
 				sysfs_unlink_rdev(mddev, rdev);
 
-		set_capacity(disk, 0);
+		set_capacity_and_notify(disk, 0);
 		mutex_unlock(&mddev->open_mutex);
 		mddev->changed = 1;
-		revalidate_disk_size(disk, true);
 
 		if (mddev->ro)
 			mddev->ro = 0;
···
 			break;
 		}
 
-		md_probe(dev, NULL, NULL);
+		md_probe(dev);
 		mddev = mddev_find(dev);
 		if (!mddev || !mddev->gendisk) {
 			if (mddev)
···
 		if (mddev_is_clustered(mddev))
 			md_cluster_ops->update_size(mddev, old_dev_sectors);
 		else if (mddev->queue) {
-			set_capacity(mddev->gendisk, mddev->array_sectors);
-			revalidate_disk_size(mddev->gendisk, true);
+			set_capacity_and_notify(mddev->gendisk,
+						mddev->array_sectors);
 		}
 	}
 	return rv;
···
 {
 	switch (cmd) {
 	case ADD_NEW_DISK:
-	case BLKROSET:
 	case GET_ARRAY_INFO:
 	case GET_BITMAP_FILE:
 	case GET_DISK_INFO:
···
 	int err = 0;
 	void __user *argp = (void __user *)arg;
 	struct mddev *mddev = NULL;
-	int ro;
 	bool did_set_md_closing = false;
 
 	if (!md_ioctl_valid(cmd))
···
 			goto unlock;
 		}
 		break;
-
-	case BLKROSET:
-		if (get_user(ro, (int __user *)(arg))) {
-			err = -EFAULT;
-			goto unlock;
-		}
-		err = -EINVAL;
-
-		/* if the bdev is going readonly the value of mddev->ro
-		 * does not matter, no writes are coming
-		 */
-		if (ro)
-			goto unlock;
-
-		/* are we are already prepared for writes? */
-		if (mddev->ro != 1)
-			goto unlock;
-
-		/* transitioning to readauto need only happen for
-		 * arrays that call md_write_start
-		 */
-		if (mddev->pers) {
-			err = restart_array(mddev);
-			if (err == 0) {
-				mddev->ro = 2;
-				set_disk_ro(mddev->gendisk, 0);
-			}
-		}
-		goto unlock;
 	}
 
 	/*
···
 }
 #endif /* CONFIG_COMPAT */
 
+static int md_set_read_only(struct block_device *bdev, bool ro)
+{
+	struct mddev *mddev = bdev->bd_disk->private_data;
+	int err;
+
+	err = mddev_lock(mddev);
+	if (err)
+		return err;
+
+	if (!mddev->raid_disks && !mddev->external) {
+		err = -ENODEV;
+		goto out_unlock;
+	}
+
+	/*
+	 * Transitioning to read-auto need only happen for arrays that call
+	 * md_write_start and which are not ready for writes yet.
+	 */
+	if (!ro && mddev->ro == 1 && mddev->pers) {
+		err = restart_array(mddev);
+		if (err)
+			goto out_unlock;
+		mddev->ro = 2;
+	}
+
+out_unlock:
+	mddev_unlock(mddev);
+	return err;
+}
+
 static int md_open(struct block_device *bdev, fmode_t mode)
 {
 	/*
···
 #endif
 	.getgeo		= md_getgeo,
 	.check_events	= md_check_events,
+	.set_read_only	= md_set_read_only,
 };
 
 static int md_thread(void *arg)
···
 	rcu_read_lock();
 	rdev_for_each_rcu(rdev, mddev) {
 		struct gendisk *disk = rdev->bdev->bd_disk;
-		curr_events = (int)part_stat_read_accum(&disk->part0, sectors) -
+		curr_events = (int)part_stat_read_accum(disk->part0, sectors) -
 			      atomic_read(&disk->sync_io);
 		/* sync IO will cause sync_io to increase before the disk_stats
 		 * as sync_io is counted when a request starts, and
···
 		mddev_lock_nointr(mddev);
 		md_set_array_sectors(mddev, mddev->pers->size(mddev, 0, 0));
 		mddev_unlock(mddev);
-		if (!mddev_is_clustered(mddev)) {
-			set_capacity(mddev->gendisk, mddev->array_sectors);
-			revalidate_disk_size(mddev->gendisk, true);
-		}
+		if (!mddev_is_clustered(mddev))
+			set_capacity_and_notify(mddev->gendisk,
+						mddev->array_sectors);
 	}
 
 	spin_lock(&mddev->lock);
···
 	if (!md_rdev_misc_wq)
 		goto err_rdev_misc_wq;
 
-	if ((ret = register_blkdev(MD_MAJOR, "md")) < 0)
+	ret = __register_blkdev(MD_MAJOR, "md", md_probe);
+	if (ret < 0)
 		goto err_md;
 
-	if ((ret = register_blkdev(0, "mdp")) < 0)
+	ret = __register_blkdev(0, "mdp", md_probe);
+	if (ret < 0)
 		goto err_mdp;
 	mdp_major = ret;
-
-	blk_register_region(MKDEV(MD_MAJOR, 0), 512, THIS_MODULE,
-			    md_probe, NULL, NULL);
-	blk_register_region(MKDEV(mdp_major, 0), 1UL<<MINORBITS, THIS_MODULE,
-			    md_probe, NULL, NULL);
 
 	register_reboot_notifier(&md_notifier);
 	raid_table_header = register_sysctl_table(raid_root_table);
···
 	struct mddev *mddev;
 	struct list_head *tmp;
 	int delay = 1;
-
-	blk_unregister_region(MKDEV(MD_MAJOR,0), 512);
-	blk_unregister_region(MKDEV(mdp_major,0), 1U << MINORBITS);
 
 	unregister_blkdev(MD_MAJOR,"md");
 	unregister_blkdev(mdp_major, "mdp");

drivers/md/raid0.c

···
 		bio_chain(discard_bio, bio);
 		bio_clone_blkg_association(discard_bio, bio);
 		if (mddev->gendisk)
-			trace_block_bio_remap(bdev_get_queue(rdev->bdev),
-				discard_bio, disk_devt(mddev->gendisk),
+			trace_block_bio_remap(discard_bio,
+				disk_devt(mddev->gendisk),
 				bio->bi_iter.bi_sector);
 		submit_bio_noacct(discard_bio);
 	}
···
 		tmp_dev->data_offset;
 
 	if (mddev->gendisk)
-		trace_block_bio_remap(bio->bi_disk->queue, bio,
-				disk_devt(mddev->gendisk), bio_sector);
+		trace_block_bio_remap(bio, disk_devt(mddev->gendisk),
+				      bio_sector);
 	mddev_check_writesame(mddev, bio);
 	mddev_check_write_zeroes(mddev, bio);
 	submit_bio_noacct(bio);

drivers/md/raid1.c

···
 	read_bio->bi_private = r1_bio;
 
 	if (mddev->gendisk)
-	        trace_block_bio_remap(read_bio->bi_disk->queue, read_bio,
-				disk_devt(mddev->gendisk), r1_bio->sector);
+	        trace_block_bio_remap(read_bio, disk_devt(mddev->gendisk),
+				      r1_bio->sector);
 
 	submit_bio_noacct(read_bio);
 }
···
 		atomic_inc(&r1_bio->remaining);
 
 		if (mddev->gendisk)
-			trace_block_bio_remap(mbio->bi_disk->queue,
-					      mbio, disk_devt(mddev->gendisk),
+			trace_block_bio_remap(mbio, disk_devt(mddev->gendisk),
 					      r1_bio->sector);
 		/* flush_pending_writes() needs access to the rdev so...*/
 		mbio->bi_disk = (void *)conf->mirrors[i].rdev;

drivers/md/raid10.c

···
 	read_bio->bi_private = r10_bio;
 
 	if (mddev->gendisk)
-	        trace_block_bio_remap(read_bio->bi_disk->queue,
-	                              read_bio, disk_devt(mddev->gendisk),
+	        trace_block_bio_remap(read_bio, disk_devt(mddev->gendisk),
 	                              r10_bio->sector);
 	submit_bio_noacct(read_bio);
 	return;
···
 	mbio->bi_private = r10_bio;
 
 	if (conf->mddev->gendisk)
-		trace_block_bio_remap(mbio->bi_disk->queue,
-				      mbio, disk_devt(conf->mddev->gendisk),
+		trace_block_bio_remap(mbio, disk_devt(conf->mddev->gendisk),
 				      r10_bio->sector);
 	/* flush_pending_writes() needs access to the rdev so...*/
 	mbio->bi_disk = (void *)rdev;

drivers/md/raid5.c

···
 				set_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags);
 
 			if (conf->mddev->gendisk)
-				trace_block_bio_remap(bi->bi_disk->queue,
-						      bi, disk_devt(conf->mddev->gendisk),
-						      sh->dev[i].sector);
+				trace_block_bio_remap(bi,
+						disk_devt(conf->mddev->gendisk),
+						sh->dev[i].sector);
 			if (should_defer && op_is_write(op))
 				bio_list_add(&pending_bios, bi);
 			else
···
 			if (op == REQ_OP_DISCARD)
 				rbi->bi_vcnt = 0;
 			if (conf->mddev->gendisk)
-				trace_block_bio_remap(rbi->bi_disk->queue,
-						      rbi, disk_devt(conf->mddev->gendisk),
-						      sh->dev[i].sector);
+				trace_block_bio_remap(rbi,
+						disk_devt(conf->mddev->gendisk),
+						sh->dev[i].sector);
 			if (should_defer && op_is_write(op))
 				bio_list_add(&pending_bios, rbi);
 			else
···
 		spin_unlock_irq(&conf->device_lock);
 
 		if (mddev->gendisk)
-			trace_block_bio_remap(align_bi->bi_disk->queue,
-					      align_bi, disk_devt(mddev->gendisk),
+			trace_block_bio_remap(align_bi, disk_devt(mddev->gendisk),
 					      raid_bio->bi_iter.bi_sector);
 		submit_bio_noacct(align_bi);
 		return 1;

drivers/mtd/mtd_blkdevs.c

···
 	return ret;
 }
 
-static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
-			      unsigned int cmd, unsigned long arg)
-{
-	struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk);
-	int ret = -ENXIO;
-
-	if (!dev)
-		return ret;
-
-	mutex_lock(&dev->lock);
-
-	if (!dev->mtd)
-		goto unlock;
-
-	switch (cmd) {
-	case BLKFLSBUF:
-		ret = dev->tr->flush ? dev->tr->flush(dev) : 0;
-		break;
-	default:
-		ret = -ENOTTY;
-	}
-unlock:
-	mutex_unlock(&dev->lock);
-	blktrans_dev_put(dev);
-	return ret;
-}
-
 static const struct block_device_operations mtd_block_ops = {
 	.owner		= THIS_MODULE,
 	.open		= blktrans_open,
 	.release	= blktrans_release,
-	.ioctl		= blktrans_ioctl,
 	.getgeo		= blktrans_getgeo,
 };
 

drivers/mtd/mtdsuper.c

···
 				struct fs_context *fc))
 {
 #ifdef CONFIG_BLOCK
-	struct block_device *bdev;
-	int ret, major;
+	dev_t dev;
+	int ret;
 #endif
 	int mtdnr;
 
···
 	/* try the old way - the hack where we allowed users to mount
 	 * /dev/mtdblock$(n) but didn't actually _use_ the blockdev
 	 */
-	bdev = lookup_bdev(fc->source);
-	if (IS_ERR(bdev)) {
-		ret = PTR_ERR(bdev);
+	ret = lookup_bdev(fc->source, &dev);
+	if (ret) {
 		errorf(fc, "MTD: Couldn't look up '%s': %d", fc->source, ret);
 		return ret;
 	}
 	pr_debug("MTDSB: lookup_bdev() returned 0\n");
 
-	major = MAJOR(bdev->bd_dev);
-	mtdnr = MINOR(bdev->bd_dev);
-	bdput(bdev);
-
-	if (major == MTD_BLOCK_MAJOR)
-		return mtd_get_sb_by_nr(fc, mtdnr, fill_super);
+	if (MAJOR(dev) == MTD_BLOCK_MAJOR)
+		return mtd_get_sb_by_nr(fc, MINOR(dev), fill_super);
 
 #endif /* CONFIG_BLOCK */
 

drivers/nvme/host/core.c

···
 static void nvme_remove_invalid_namespaces(struct nvme_ctrl *ctrl,
 					   unsigned nsid);
 
-static void nvme_update_bdev_size(struct gendisk *disk)
-{
-	struct block_device *bdev = bdget_disk(disk, 0);
-
-	if (bdev) {
-		bd_set_nr_sectors(bdev, get_capacity(disk));
-		bdput(bdev);
-	}
-}
-
 /*
  * Prepare a queue for teardown.
  *
···
 	blk_set_queue_dying(ns->queue);
 	blk_mq_unquiesce_queue(ns->queue);
 
-	set_capacity(ns->disk, 0);
-	nvme_update_bdev_size(ns->disk);
+	set_capacity_and_notify(ns->disk, 0);
 }
 
 static void nvme_queue_scan(struct nvme_ctrl *ctrl)
···
 			capacity = 0;
 	}
 
-	set_capacity_revalidate_and_notify(disk, capacity, false);
+	set_capacity_and_notify(disk, capacity);
 
 	nvme_config_discard(disk, ns);
 	nvme_config_write_zeroes(disk, ns);
···
 		blk_stack_limits(&ns->head->disk->queue->limits,
 				 &ns->queue->limits, 0);
 		blk_queue_update_readahead(ns->head->disk->queue);
-		nvme_update_bdev_size(ns->head->disk);
 		blk_mq_unfreeze_queue(ns->head->disk->queue);
 	}
 #endif
···
 	 */
 	if (ret && ret != -ENOMEM && !(ret > 0 && !(ret & NVME_SC_DNR)))
 		nvme_ns_remove(ns);
-	else
-		revalidate_disk_size(ns->disk, true);
 }
 
 static void nvme_validate_or_alloc_ns(struct nvme_ctrl *ctrl, unsigned nsid)

drivers/nvme/host/multipath.c

···
 	if (likely(ns)) {
 		bio->bi_disk = ns->disk;
 		bio->bi_opf |= REQ_NVME_MPATH;
-		trace_block_bio_remap(bio->bi_disk->queue, bio,
-				      disk_devt(ns->head->disk),
+		trace_block_bio_remap(bio, disk_devt(ns->head->disk),
 				      bio->bi_iter.bi_sector);
 		ret = submit_bio_noacct(bio);
 	} else if (nvme_available_path(head)) {

drivers/nvme/target/admin-cmd.c

···
 	if (!ns->bdev)
 		goto out;
 
-	host_reads = part_stat_read(ns->bdev->bd_part, ios[READ]);
-	data_units_read = DIV_ROUND_UP(part_stat_read(ns->bdev->bd_part,
-		sectors[READ]), 1000);
-	host_writes = part_stat_read(ns->bdev->bd_part, ios[WRITE]);
-	data_units_written = DIV_ROUND_UP(part_stat_read(ns->bdev->bd_part,
-		sectors[WRITE]), 1000);
+	host_reads = part_stat_read(ns->bdev, ios[READ]);
+	data_units_read =
+		DIV_ROUND_UP(part_stat_read(ns->bdev, sectors[READ]), 1000);
+	host_writes = part_stat_read(ns->bdev, ios[WRITE]);
+	data_units_written =
+		DIV_ROUND_UP(part_stat_read(ns->bdev, sectors[WRITE]), 1000);
 
 	put_unaligned_le64(host_reads, &slog->host_reads[0]);
 	put_unaligned_le64(data_units_read, &slog->data_units_read[0]);
···
 		/* we don't have the right data for file backed ns */
 		if (!ns->bdev)
 			continue;
-		host_reads += part_stat_read(ns->bdev->bd_part, ios[READ]);
+		host_reads += part_stat_read(ns->bdev, ios[READ]);
 		data_units_read += DIV_ROUND_UP(
-			part_stat_read(ns->bdev->bd_part, sectors[READ]), 1000);
-		host_writes += part_stat_read(ns->bdev->bd_part, ios[WRITE]);
+			part_stat_read(ns->bdev, sectors[READ]), 1000);
+		host_writes += part_stat_read(ns->bdev, ios[WRITE]);
 		data_units_written += DIV_ROUND_UP(
-			part_stat_read(ns->bdev->bd_part, sectors[WRITE]), 1000);
+			part_stat_read(ns->bdev, sectors[WRITE]), 1000);
 	}
 
 	put_unaligned_le64(host_reads, &slog->host_reads[0]);

drivers/nvme/target/loop.c

···
 			(set == &ctrl->tag_set) ? hctx_idx + 1 : 0);
 }
 
+static struct lock_class_key loop_hctx_fq_lock_key;
+
 static int nvme_loop_init_hctx(struct blk_mq_hw_ctx *hctx, void *data,
 		unsigned int hctx_idx)
 {
···
 	struct nvme_loop_queue *queue = &ctrl->queues[hctx_idx + 1];
 
 	BUG_ON(hctx_idx >= ctrl->ctrl.queue_count);
+
+	/*
+	 * flush_end_io() can be called recursively for us, so use our own
+	 * lock class key for avoiding lockdep possible recursive locking,
+	 * then we can remove the dynamically allocated lock class for each
+	 * flush queue, that way may cause horrible boot delay.
+	 */
+	blk_mq_hctx_set_fq_lock_class(hctx, &loop_hctx_fq_lock_key);
 
 	hctx->driver_data = queue;
 	return 0;

drivers/s390/block/dasd.c

···
 {
 	struct gendisk *disk;
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 
 	device->state = DASD_STATE_ONLINE;
 	if (device->block) {
···
 		disk = device->block->bdev->bd_disk;
 		disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
 		while ((part = disk_part_iter_next(&piter)))
-			kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
+			kobject_uevent(bdev_kobj(part), KOBJ_CHANGE);
 		disk_part_iter_exit(&piter);
 	}
 	return 0;
···
 	int rc;
 	struct gendisk *disk;
 	struct disk_part_iter piter;
-	struct hd_struct *part;
+	struct block_device *part;
 
 	if (device->discipline->online_to_ready) {
 		rc = device->discipline->online_to_ready(device);
···
 		disk = device->block->bdev->bd_disk;
 		disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
 		while ((part = disk_part_iter_next(&piter)))
-			kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
+			kobject_uevent(bdev_kobj(part), KOBJ_CHANGE);
 		disk_part_iter_exit(&piter);
 	}
 	return 0;
···
 	.ioctl		= dasd_ioctl,
 	.compat_ioctl	= dasd_ioctl,
 	.getgeo		= dasd_getgeo,
+	.set_read_only	= dasd_set_read_only,
 };
 
 /*******************************************************************************

drivers/s390/block/dasd_int.h

···
 void dasd_destroy_partitions(struct dasd_block *);
 
 /* externals in dasd_ioctl.c */
-int  dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);
+int dasd_ioctl(struct block_device *, fmode_t, unsigned int, unsigned long);
+int dasd_set_read_only(struct block_device *bdev, bool ro);
 
 /* externals in dasd_proc.c */
 int dasd_proc_init(void);

drivers/s390/block/dasd_ioctl.c

···
 		return -ENODEV;
 
 	dasd_enable_device(base);
-	/* Formatting the dasd device can change the capacity. */
-	bd_set_nr_sectors(bdev, get_capacity(base->block->gdp));
 	dasd_put_device(base);
 	return 0;
 }
···
 	 * Set i_size to zero, since read, write, etc. check against this
 	 * value.
 	 */
-	bd_set_nr_sectors(bdev, 0);
+	set_capacity(bdev->bd_disk, 0);
 	dasd_put_device(base);
 	return 0;
 }
···
 	 * enabling the device later.
 	 */
 	if (fdata->start_unit == 0) {
-		struct block_device *bdev = bdget_disk(block->gdp, 0);
-		bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
-		bdput(bdev);
+		block->gdp->part0->bd_inode->i_blkbits =
+			blksize_bits(fdata->blksize);
 	}
 
 	rc = base->discipline->format_device(base, fdata, 1);
···
 /*
  * Set read only
  */
-static int
-dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
+int dasd_set_read_only(struct block_device *bdev, bool ro)
 {
 	struct dasd_device *base;
-	int intval, rc;
+	int rc;
 
-	if (!capable(CAP_SYS_ADMIN))
-		return -EACCES;
+	/* do not manipulate hardware state for partitions */
 	if (bdev_is_partition(bdev))
-		// ro setting is not allowed for partitions
-		return -EINVAL;
-	if (get_user(intval, (int __user *)argp))
-		return -EFAULT;
+		return 0;
+
 	base = dasd_device_from_gendisk(bdev->bd_disk);
 	if (!base)
 		return -ENODEV;
-	if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
-		dasd_put_device(base);
-		return -EROFS;
-	}
-	set_disk_ro(bdev->bd_disk, intval);
-	rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
+	if (!ro && test_bit(DASD_FLAG_DEVICE_RO, &base->flags))
+		rc = -EROFS;
+	else
+		rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, ro);
 	dasd_put_device(base);
 	return rc;
 }
···
 		break;
 	case BIODASDPRRST:
 		rc = dasd_ioctl_reset_profile(block);
-		break;
-	case BLKROSET:
-		rc = dasd_ioctl_set_ro(bdev, argp);
 		break;
 	case DASDAPIVER:
 		rc = dasd_ioctl_api_version(argp);

drivers/s390/scsi/zfcp_fsf.c

···
 		}
 	}
 
-	blk_add_driver_data(scsi->request->q, scsi->request, &blktrc,
-			    sizeof(blktrc));
+	blk_add_driver_data(scsi->request, &blktrc, sizeof(blktrc));
 }
 
 /**

drivers/scsi/scsicam.c

···
  */
 unsigned char *scsi_bios_ptable(struct block_device *dev)
 {
-	struct address_space *mapping = dev->bd_contains->bd_inode->i_mapping;
+	struct address_space *mapping = bdev_whole(dev)->bd_inode->i_mapping;
 	unsigned char *res = NULL;
 	struct page *page;
 

drivers/scsi/sd.c

···
 };
 
 /*
- * Dummy kobj_map->probe function.
- * The default ->probe function will call modprobe, which is
- * pointless as this module is already loaded.
+ * Don't request a new module, as that could deadlock in multipath
+ * environment.
  */
-static struct kobject *sd_default_probe(dev_t devt, int *partno, void *data)
+static void sd_default_probe(dev_t devt)
 {
-	return NULL;
 }
 
 /*
···
 static void sd_rescan(struct device *dev)
 {
 	struct scsi_disk *sdkp = dev_get_drvdata(dev);
-	int ret;
 
-	ret = sd_revalidate_disk(sdkp->disk);
-	revalidate_disk_size(sdkp->disk, ret == 0);
+	sd_revalidate_disk(sdkp->disk);
 }
 
 static int sd_ioctl(struct block_device *bdev, fmode_t mode,
···
 
 	sdkp->first_scan = 0;
 
-	set_capacity_revalidate_and_notify(disk,
-		logical_to_sectors(sdp, sdkp->capacity), false);
+	set_capacity_and_notify(disk, logical_to_sectors(sdp, sdkp->capacity));
 	sd_config_write_same(sdkp);
 	kfree(buffer);
 
···
 	 * capacity to 0.
 	 */
 	if (sd_zbc_revalidate_zones(sdkp))
-		set_capacity_revalidate_and_notify(disk, 0, false);
+		set_capacity_and_notify(disk, 0);
 
  out:
 	return 0;
···
 
 	free_opal_dev(sdkp->opal_dev);
 
-	blk_register_region(devt, SD_MINORS, NULL,
-			    sd_default_probe, NULL, NULL);
-
 	mutex_lock(&sd_ref_mutex);
 	dev_set_drvdata(dev, NULL);
 	put_device(&sdkp->dev);
···
 	SCSI_LOG_HLQUEUE(3, printk("init_sd: sd driver entry point\n"));
 
 	for (i = 0; i < SD_MAJORS; i++) {
-		if (register_blkdev(sd_major(i), "sd") != 0)
+		if (__register_blkdev(sd_major(i), "sd", sd_default_probe))
 			continue;
 		majors++;
-		blk_register_region(sd_major(i), SD_MINORS, NULL,
-				    sd_default_probe, NULL, NULL);
 	}
 
 	if (!majors)
···
 
 	class_unregister(&sd_disk_class);
 
-	for (i = 0; i < SD_MAJORS; i++) {
-		blk_unregister_region(sd_major(i), SD_MINORS);
+	for (i = 0; i < SD_MAJORS; i++)
 		unregister_blkdev(sd_major(i), "sd");
-	}
 }
 
 module_init(init_sd);

drivers/target/target_core_file.c

···
 	 */
 	inode = file->f_mapping->host;
 	if (S_ISBLK(inode->i_mode)) {
-		struct request_queue *q = bdev_get_queue(inode->i_bdev);
+		struct request_queue *q = bdev_get_queue(I_BDEV(inode));
 		unsigned long long dev_size;
 
-		fd_dev->fd_block_size = bdev_logical_block_size(inode->i_bdev);
+		fd_dev->fd_block_size = bdev_logical_block_size(I_BDEV(inode));
 		/*
 		 * Determine the number of bytes from i_size_read() minus
 		 * one (1) logical sector from underlying struct block_device
···
 
 	if (S_ISBLK(inode->i_mode)) {
 		/* The backend is block device, use discard */
-		struct block_device *bdev = inode->i_bdev;
+		struct block_device *bdev = I_BDEV(inode);
 		struct se_device *dev = cmd->se_dev;
 
 		ret = blkdev_issue_discard(bdev,

drivers/target/target_core_pscsi.c

···
 {
 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 
-	if (pdv->pdv_bd && pdv->pdv_bd->bd_part)
-		return pdv->pdv_bd->bd_part->nr_sects;
-
+	if (pdv->pdv_bd)
+		return bdev_nr_sectors(pdv->pdv_bd);
 	return 0;
 }
 

drivers/usb/gadget/function/storage_common.c

···
 	if (!(filp->f_mode & FMODE_WRITE))
 		ro = 1;
 
-	inode = file_inode(filp);
+	inode = filp->f_mapping->host;
 	if ((!S_ISREG(inode->i_mode) && !S_ISBLK(inode->i_mode))) {
 		LINFO(curlun, "invalid file type: %s\n", filename);
 		goto out;
···
 	if (!(filp->f_mode & FMODE_CAN_WRITE))
 		ro = 1;
 
-	size = i_size_read(inode->i_mapping->host);
+	size = i_size_read(inode);
 	if (size < 0) {
 		LINFO(curlun, "unable to find file size: %s\n", filename);
 		rc = (int) size;
···
 	if (curlun->cdrom) {
 		blksize = 2048;
 		blkbits = 11;
-	} else if (inode->i_bdev) {
-		blksize = bdev_logical_block_size(inode->i_bdev);
+	} else if (S_ISBLK(inode->i_mode)) {
+		blksize = bdev_logical_block_size(I_BDEV(inode));
 		blkbits = blksize_bits(blksize);
 	} else {
 		blksize = 512;

fs/block_dev.c

···
 #include <linux/cleancache.h>
 #include <linux/task_io_accounting_ops.h>
 #include <linux/falloc.h>
+#include <linux/part_stat.h>
 #include <linux/uaccess.h>
 #include <linux/suspend.h>
 #include "internal.h"
···
 int truncate_bdev_range(struct block_device *bdev, fmode_t mode,
 			loff_t lstart, loff_t lend)
 {
-	struct block_device *claimed_bdev = NULL;
-	int err;
-
 	/*
 	 * If we don't hold exclusive handle for the device, upgrade to it
 	 * while we discard the buffer cache to avoid discarding buffers
 	 * under live filesystem.
 	 */
 	if (!(mode & FMODE_EXCL)) {
-		claimed_bdev = bdev->bd_contains;
-		err = bd_prepare_to_claim(bdev, claimed_bdev,
-					  truncate_bdev_range);
+		int err = bd_prepare_to_claim(bdev, truncate_bdev_range);
 		if (err)
 			return err;
 	}
+
 	truncate_inode_pages_range(bdev->bd_inode->i_mapping, lstart, lend);
-	if (claimed_bdev)
-		bd_abort_claiming(bdev, claimed_bdev, truncate_bdev_range);
+	if (!(mode & FMODE_EXCL))
+		bd_abort_claiming(bdev, truncate_bdev_range);
 	return 0;
 }
 EXPORT_SYMBOL(truncate_bdev_range);
···
  * count down in thaw_bdev(). When it becomes 0, thaw_bdev() will unfreeze
  * actually.
  */
-struct super_block *freeze_bdev(struct block_device *bdev)
+int freeze_bdev(struct block_device *bdev)
 {
 	struct super_block *sb;
 	int error = 0;
 
 	mutex_lock(&bdev->bd_fsfreeze_mutex);
-	if (++bdev->bd_fsfreeze_count > 1) {
-		/*
-		 * We don't even need to grab a reference - the first call
-		 * to freeze_bdev grab an active reference and only the last
-		 * thaw_bdev drops it.
-		 */
-		sb = get_super(bdev);
-		if (sb)
-			drop_super(sb);
-		mutex_unlock(&bdev->bd_fsfreeze_mutex);
-		return sb;
-	}
+	if (++bdev->bd_fsfreeze_count > 1)
+		goto done;
 
 	sb = get_active_super(bdev);
 	if (!sb)
-		goto out;
+		goto sync;
 	if (sb->s_op->freeze_super)
 		error = sb->s_op->freeze_super(sb);
 	else
 		error = freeze_super(sb);
-	if (error) {
-		deactivate_super(sb);
-		bdev->bd_fsfreeze_count--;
-		mutex_unlock(&bdev->bd_fsfreeze_mutex);
-		return ERR_PTR(error);
-	}
 	deactivate_super(sb);
- out:
+
+	if (error) {
+		bdev->bd_fsfreeze_count--;
+		goto done;
+	}
+	bdev->bd_fsfreeze_sb = sb;
+
+sync:
 	sync_blockdev(bdev);
+done:
 	mutex_unlock(&bdev->bd_fsfreeze_mutex);
-	return sb;	/* thaw_bdev releases s->s_umount */
+	return error;
 }
 EXPORT_SYMBOL(freeze_bdev);
 
 /**
  * thaw_bdev  -- unlock filesystem
  * @bdev:	blockdevice to unlock
- * @sb:		associated superblock
  *
  * Unlocks the filesystem and marks it writeable again after freeze_bdev().
  */
-int thaw_bdev(struct block_device *bdev, struct super_block *sb)
+int thaw_bdev(struct block_device *bdev)
 {
+	struct super_block *sb;
 	int error = -EINVAL;
 
 	mutex_lock(&bdev->bd_fsfreeze_mutex);
···
 	if (--bdev->bd_fsfreeze_count > 0)
 		goto out;
 
+	sb = bdev->bd_fsfreeze_sb;
 	if (!sb)
 		goto out;
 
···
 
 static void bdev_free_inode(struct inode *inode)
 {
+	struct block_device *bdev = I_BDEV(inode);
+
+	free_percpu(bdev->bd_stats);
+	kfree(bdev->bd_meta_info);
+
 	kmem_cache_free(bdev_cachep, BDEV_I(inode));
 }
 
-static void init_once(void *foo)
+static void init_once(void *data)
 {
-	struct bdev_inode *ei = (struct bdev_inode *) foo;
-	struct block_device *bdev = &ei->bdev;
+	struct bdev_inode *ei = data;
 
-	memset(bdev, 0, sizeof(*bdev));
-	mutex_init(&bdev->bd_mutex);
-#ifdef CONFIG_SYSFS
-	INIT_LIST_HEAD(&bdev->bd_holder_disks);
-#endif
-	bdev->bd_bdi = &noop_backing_dev_info;
 	inode_init_once(&ei->vfs_inode);
-	/* Initialize mutex for freeze. */
-	mutex_init(&bdev->bd_fsfreeze_mutex);
 }
 
 static void bdev_evict_inode(struct inode *inode)
···
 	blockdev_superblock = bd_mnt->mnt_sb;   /* For writeback */
 }
 
-/*
- * Most likely _very_ bad one - but then it's hardly critical for small
- * /dev and can be fixed when somebody will need really large one.
- * Keep in mind that it will be fed through icache hash function too.
- */
-static inline unsigned long hash(dev_t dev)
-{
-	return MAJOR(dev)+MINOR(dev);
-}
-
-static int bdev_test(struct inode *inode, void *data)
-{
-	return BDEV_I(inode)->bdev.bd_dev == *(dev_t *)data;
-}
-
-static int bdev_set(struct inode *inode, void *data)
-{
-	BDEV_I(inode)->bdev.bd_dev = *(dev_t *)data;
-	return 0;
-}
-
-static struct block_device *bdget(dev_t dev)
+struct block_device *bdev_alloc(struct gendisk *disk, u8 partno)
 {
 	struct block_device *bdev;
 	struct inode *inode;
 
-	inode = iget5_locked(blockdev_superblock, hash(dev),
-			bdev_test, bdev_set, &dev);
-
+	inode = new_inode(blockdev_superblock);
 	if (!inode)
 		return NULL;
+	inode->i_mode = S_IFBLK;
+	inode->i_rdev = 0;
+	inode->i_data.a_ops = &def_blk_aops;
+	mapping_set_gfp_mask(&inode->i_data, GFP_USER);
 
-	bdev = &BDEV_I(inode)->bdev;
-
-	if (inode->i_state & I_NEW) {
-		spin_lock_init(&bdev->bd_size_lock);
-		bdev->bd_contains = NULL;
-		bdev->bd_super = NULL;
-		bdev->bd_inode = inode;
-		bdev->bd_part_count = 0;
-		inode->i_mode = S_IFBLK;
-		inode->i_rdev = dev;
-		inode->i_bdev = bdev;
-		inode->i_data.a_ops = &def_blk_aops;
-		mapping_set_gfp_mask(&inode->i_data, GFP_USER);
-		unlock_new_inode(inode);
+	bdev = I_BDEV(inode);
+	memset(bdev, 0, sizeof(*bdev));
+	mutex_init(&bdev->bd_mutex);
+	mutex_init(&bdev->bd_fsfreeze_mutex);
+	spin_lock_init(&bdev->bd_size_lock);
+	bdev->bd_disk = disk;
+	bdev->bd_partno = partno;
+	bdev->bd_inode = inode;
+	bdev->bd_bdi = &noop_backing_dev_info;
+#ifdef CONFIG_SYSFS
+	INIT_LIST_HEAD(&bdev->bd_holder_disks);
+#endif
+	bdev->bd_stats = alloc_percpu(struct disk_stats);
+	if (!bdev->bd_stats) {
+		iput(inode);
+		return NULL;
 	}
 	return bdev;
+}
+
+void bdev_add(struct block_device *bdev, dev_t dev)
+{
+	bdev->bd_dev = dev;
+	bdev->bd_inode->i_rdev = dev;
+	bdev->bd_inode->i_ino = dev;
+	insert_inode_hash(bdev->bd_inode);
+}
+
+static struct block_device *bdget(dev_t dev)
+{
+	struct inode *inode;
+
+	inode = ilookup(blockdev_superblock, dev);
+	if (!inode)
+		return NULL;
+	return &BDEV_I(inode)->bdev;
 }
 
 /**
  * bdgrab -- Grab a reference to an already referenced block device
  * @bdev:	Block device to grab a reference to.
+ *
+ * Returns the block_device with an additional reference when successful,
+ * or NULL if the inode is already beeing freed.
  */
 struct block_device *bdgrab(struct block_device *bdev)
 {
-	ihold(bdev->bd_inode);
+	if (!igrab(bdev->bd_inode))
+		return NULL;
 	return bdev;
 }
 EXPORT_SYMBOL(bdgrab);
-
-struct block_device *bdget_part(struct hd_struct *part)
-{
-	return bdget(part_devt(part));
-}
 
 long nr_blockdev_pages(void)
 {
···
 {
 	iput(bdev->bd_inode);
 }
-
 EXPORT_SYMBOL(bdput);
  
-static struct block_device *bd_acquire(struct inode *inode)
-{
-	struct block_device *bdev;
-
-	spin_lock(&bdev_lock);
-	bdev = inode->i_bdev;
-	if (bdev && !inode_unhashed(bdev->bd_inode)) {
-		bdgrab(bdev);
-		spin_unlock(&bdev_lock);
-		return bdev;
-	}
-	spin_unlock(&bdev_lock);
-
-	/*
-	 * i_bdev references block device inode that was already shut down
-	 * (corresponding device got removed).  Remove the reference and look
-	 * up block device inode again just in case new device got
-	 * reestablished under the same device number.
-	 */
-	if (bdev)
-		bd_forget(inode);
-
-	bdev = bdget(inode->i_rdev);
-	if (bdev) {
-		spin_lock(&bdev_lock);
-		if (!inode->i_bdev) {
-			/*
-			 * We take an additional reference to bd_inode,
-			 * and it's released in clear_inode() of inode.
-			 * So, we can access it via ->i_mapping always
-			 * without igrab().
-			 */
-			bdgrab(bdev);
-			inode->i_bdev = bdev;
-			inode->i_mapping = bdev->bd_inode->i_mapping;
-		}
-		spin_unlock(&bdev_lock);
-	}
-	return bdev;
-}
-
-/* Call when you free inode */
-
-void bd_forget(struct inode *inode)
-{
-	struct block_device *bdev = NULL;
-
-	spin_lock(&bdev_lock);
-	if (!sb_is_blkdev_sb(inode->i_sb))
-		bdev = inode->i_bdev;
-	inode->i_bdev = NULL;
-	inode->i_mapping = &inode->i_data;
-	spin_unlock(&bdev_lock);
-
-	if (bdev)
-		bdput(bdev);
-}
-
 /**
  * bd_may_claim - test whether a block device can be claimed
  * @bdev: block device of interest
···
 /**
  * bd_prepare_to_claim - claim a block device
  * @bdev: block device of interest
- * @whole: the whole device containing @bdev, may equal @bdev
  * @holder: holder trying to claim @bdev
  *
  * Claim @bdev.  This function fails if @bdev is already claimed by another
···
  * RETURNS:
  * 0 if @bdev can be claimed, -EBUSY otherwise.
  */
-int bd_prepare_to_claim(struct block_device *bdev, struct block_device *whole,
-		void *holder)
+int bd_prepare_to_claim(struct block_device *bdev, void *holder)
 {
+	struct block_device *whole = bdev_whole(bdev);
+
+	if (WARN_ON_ONCE(!holder))
+		return -EINVAL;
 retry:
 	spin_lock(&bdev_lock);
 	/* if someone else claimed, fail */
···
 }
 EXPORT_SYMBOL_GPL(bd_prepare_to_claim); /* only for the loop driver */
 
-static struct gendisk *bdev_get_gendisk(struct block_device *bdev, int *partno)
-{
-	struct gendisk *disk = get_gendisk(bdev->bd_dev, partno);
-
-	if (!disk)
-		return NULL;
-	/*
-	 * Now that we hold gendisk reference we make sure bdev we looked up is
-	 * not stale. If it is, it means device got removed and created before
-	 * we looked up gendisk and we fail open in such case. Associating
-	 * unhashed bdev with newly created gendisk could lead to two bdevs
-	 * (and thus two independent caches) being associated with one device
-	 * which is bad.
-	 */
-	if (inode_unhashed(bdev->bd_inode)) {
-		put_disk_and_module(disk);
-		return NULL;
-	}
-	return disk;
-}
-
 static void bd_clear_claiming(struct block_device *whole, void *holder)
 {
 	lockdep_assert_held(&bdev_lock);
···
 /**
  * bd_finish_claiming - finish claiming of a block device
  * @bdev: block device of interest
- * @whole: whole block device
  * @holder: holder that has claimed @bdev
  *
  * Finish exclusive open of a block device. Mark the device as exlusively
  * open by the holder and wake up all waiters for exclusive open to finish.
  */
-static void bd_finish_claiming(struct block_device *bdev,
-		struct block_device *whole, void *holder)
+static void bd_finish_claiming(struct block_device *bdev, void *holder)
 {
+	struct block_device *whole = bdev_whole(bdev);
+
 	spin_lock(&bdev_lock);
 	BUG_ON(!bd_may_claim(bdev, whole, holder));
 	/*
···
  * also used when exclusive open is not actually desired and we just needed
  * to block other exclusive openers for a while.
  */
-void bd_abort_claiming(struct block_device *bdev, struct block_device *whole,
-		       void *holder)
+void bd_abort_claiming(struct block_device *bdev, void *holder)
 {
 	spin_lock(&bdev_lock);
-	bd_clear_claiming(whole, holder);
+	bd_clear_claiming(bdev_whole(bdev), holder);
 	spin_unlock(&bdev_lock);
 }
 EXPORT_SYMBOL(bd_abort_claiming);
···
 	WARN_ON_ONCE(!bdev->bd_holder);
 
 	/* FIXME: remove the following once add_disk() handles errors */
-	if (WARN_ON(!disk->slave_dir || !bdev->bd_part->holder_dir))
+	if (WARN_ON(!disk->slave_dir || !bdev->bd_holder_dir))
 		goto out_unlock;
 
 	holder = bd_find_holder_disk(bdev, disk);
···
 	holder->disk = disk;
 	holder->refcnt = 1;
 
-	ret = add_symlink(disk->slave_dir, &part_to_dev(bdev->bd_part)->kobj);
+	ret = add_symlink(disk->slave_dir, bdev_kobj(bdev));
 	if (ret)
 		goto out_free;
 
-	ret = add_symlink(bdev->bd_part->holder_dir, &disk_to_dev(disk)->kobj);
+	ret = add_symlink(bdev->bd_holder_dir, &disk_to_dev(disk)->kobj);
 	if (ret)
 		goto out_del;
 	/*
 	 * bdev could be deleted beneath us which would implicitly destroy
 	 * the holder directory.  Hold on to it.
 	 */
-	kobject_get(bdev->bd_part->holder_dir);
+	kobject_get(bdev->bd_holder_dir);
 
 	list_add(&holder->list, &bdev->bd_holder_disks);
 	goto out_unlock;
 
 out_del:
-	del_symlink(disk->slave_dir, &part_to_dev(bdev->bd_part)->kobj);
+	del_symlink(disk->slave_dir, bdev_kobj(bdev));
 out_free:
 	kfree(holder);
 out_unlock:
···
 	holder = bd_find_holder_disk(bdev, disk);
 
 	if (!WARN_ON_ONCE(holder == NULL) && !--holder->refcnt) {
-		del_symlink(disk->slave_dir, &part_to_dev(bdev->bd_part)->kobj);
-		del_symlink(bdev->bd_part->holder_dir,
-			    &disk_to_dev(disk)->kobj);
-		kobject_put(bdev->bd_part->holder_dir);
+		del_symlink(disk->slave_dir, bdev_kobj(bdev));
+		del_symlink(bdev->bd_holder_dir, &disk_to_dev(disk)->kobj);
+		kobject_put(bdev->bd_holder_dir);
 		list_del_init(&holder->list);
 		kfree(holder);
 	}
···
 }
 EXPORT_SYMBOL_GPL(bd_unlink_disk_holder);
 #endif
-
-/**
- * check_disk_size_change - checks for disk size change and adjusts bdev size.
- * @disk: struct gendisk to check
- * @bdev: struct bdev to adjust.
- * @verbose: if %true log a message about a size change if there is any
- *
- * This routine checks to see if the bdev size does not match the disk size
- * and adjusts it if it differs. When shrinking the bdev size, its all caches
- * are freed.
- */
-static void check_disk_size_change(struct gendisk *disk,
-		struct block_device *bdev, bool verbose)
-{
-	loff_t disk_size, bdev_size;
-
-	spin_lock(&bdev->bd_size_lock);
-	disk_size = (loff_t)get_capacity(disk) << 9;
-	bdev_size = i_size_read(bdev->bd_inode);
-	if (disk_size != bdev_size) {
-		if (verbose) {
-			printk(KERN_INFO
-			       "%s: detected capacity change from %lld to %lld\n",
-			       disk->disk_name, bdev_size, disk_size);
-		}
-		i_size_write(bdev->bd_inode, disk_size);
-	}
-	spin_unlock(&bdev->bd_size_lock);
-
-	if (bdev_size > disk_size) {
-		if (__invalidate_device(bdev, false))
-			pr_warn("VFS: busy inodes on resized disk %s\n",
-				disk->disk_name);
-	}
-}
-
-/**
- * revalidate_disk_size - checks for disk size change and adjusts bdev size.
- * @disk: struct gendisk to check
- * @verbose: if %true log a message about a size change if there is any
- *
- * This routine checks to see if the bdev size does not match the disk size
- * and adjusts it if it differs. When shrinking the bdev size, its all caches
- * are freed.
- */
-void revalidate_disk_size(struct gendisk *disk, bool verbose)
-{
-	struct block_device *bdev;
-
-	/*
-	 * Hidden disks don't have associated bdev so there's no point in
-	 * revalidating them.
-	 */
-	if (disk->flags & GENHD_FL_HIDDEN)
-		return;
-
-	bdev = bdget_disk(disk, 0);
-	if (bdev) {
-		check_disk_size_change(disk, bdev, verbose);
-		bdput(bdev);
-	}
-}
-EXPORT_SYMBOL(revalidate_disk_size);
-
-void bd_set_nr_sectors(struct block_device *bdev, sector_t sectors)
-{
-	spin_lock(&bdev->bd_size_lock);
-	i_size_write(bdev->bd_inode, (loff_t)sectors << SECTOR_SHIFT);
-	spin_unlock(&bdev->bd_size_lock);
-}
-EXPORT_SYMBOL(bd_set_nr_sectors);
 
 static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
 
···
 			disk->fops->revalidate_disk(disk);
 	}
 
-	check_disk_size_change(disk, bdev, !invalidate);
-
 	if (get_capacity(disk)) {
 		ret = blk_add_partitions(disk, bdev);
 		if (ret == -EAGAIN)
···
  *  mutex_lock(part->bd_mutex)
  *    mutex_lock_nested(whole->bd_mutex, 1)
  */
-
-static int __blkdev_get(struct block_device *bdev, fmode_t mode, void *holder,
-		int for_part)
+static int __blkdev_get(struct block_device *bdev, fmode_t mode)
 {
-	struct block_device *whole = NULL, *claiming = NULL;
-	struct gendisk *disk;
-	int ret;
-	int partno;
-	bool first_open = false, unblock_events = true, need_restart;
+	struct gendisk *disk = bdev->bd_disk;
+	int ret = 0;
 
- restart:
-	need_restart = false;
-	ret = -ENXIO;
-	disk = bdev_get_gendisk(bdev, &partno);
-	if (!disk)
-		goto out;
-
-	if (partno) {
-		whole = bdget_disk(disk, 0);
-		if (!whole) {
-			ret = -ENOMEM;
-			goto out_put_disk;
-		}
-	}
-
-	if (!for_part && (mode & FMODE_EXCL)) {
-		WARN_ON_ONCE(!holder);
-		if (whole)
-			claiming = whole;
-		else
-			claiming = bdev;
-		ret = bd_prepare_to_claim(bdev, claiming, holder);
-		if (ret)
-			goto out_put_whole;
-	}
-
-	disk_block_events(disk);
-	mutex_lock_nested(&bdev->bd_mutex, for_part);
 	if (!bdev->bd_openers) {
-		first_open = true;
-		bdev->bd_disk = disk;
-		bdev->bd_contains = bdev;
-		bdev->bd_partno = partno;
-
-		if (!partno) {
-			ret = -ENXIO;
-			bdev->bd_part = disk_get_part(disk, partno);
-			if (!bdev->bd_part)
-				goto out_clear;
-
+		if (!bdev_is_partition(bdev)) {
 			ret = 0;
-			if (disk->fops->open) {
+			if (disk->fops->open)
 				ret = disk->fops->open(bdev, mode);
-				/*
-				 * If we lost a race with 'disk' being deleted,
-				 * try again.  See md.c
-				 */
-				if (ret == -ERESTARTSYS)
-					need_restart = true;
-			}
 
-			if (!ret) {
-				bd_set_nr_sectors(bdev, get_capacity(disk));
+			if (!ret)
 				set_init_blocksize(bdev);
-			}
 
 			/*
 			 * If the device is invalidated, rescan partition
···
 				bdev_disk_changed(bdev, ret == -ENOMEDIUM);
 
 			if (ret)
-				goto out_clear;
+				return ret;
 		} else {
-			BUG_ON(for_part);
-			ret = __blkdev_get(whole, mode, NULL, 1);
-			if (ret)
-				goto out_clear;
-			bdev->bd_contains = bdgrab(whole);
-			bdev->bd_part = disk_get_part(disk, partno);
-			if (!(disk->flags & GENHD_FL_UP) ||
-			    !bdev->bd_part || !bdev->bd_part->nr_sects) {
-				ret = -ENXIO;
-				goto out_clear;
+			struct block_device *whole = bdgrab(disk->part0);
+
+			mutex_lock_nested(&whole->bd_mutex, 1);
+			ret = __blkdev_get(whole, mode);
+			if (ret) {
+				mutex_unlock(&whole->bd_mutex);
+				bdput(whole);
+				return ret;
 			}
-			bd_set_nr_sectors(bdev, bdev->bd_part->nr_sects);
+			whole->bd_part_count++;
+			mutex_unlock(&whole->bd_mutex);
+
+			if (!(disk->flags & GENHD_FL_UP) ||
+			    !bdev_nr_sectors(bdev)) {
+				__blkdev_put(whole, mode, 1);
+				bdput(whole);
+				return -ENXIO;
+			}
 			set_init_blocksize(bdev);
 		}
 
 		if (bdev->bd_bdi == &noop_backing_dev_info)
 			bdev->bd_bdi = bdi_get(disk->queue->backing_dev_info);
 	} else {
-		if (bdev->bd_contains == bdev) {
-			ret = 0;
+		if (!bdev_is_partition(bdev)) {
 			if (bdev->bd_disk->fops->open)
 				ret = bdev->bd_disk->fops->open(bdev, mode);
 			/* the same as first opener case, read comment there */
···
 			    (!ret || ret == -ENOMEDIUM))
 				bdev_disk_changed(bdev, ret == -ENOMEDIUM);
 			if (ret)
-				goto out_unlock_bdev;
+				return ret;
 		}
 	}
 	bdev->bd_openers++;
-	if (for_part)
-		bdev->bd_part_count++;
-	if (claiming)
-		bd_finish_claiming(bdev, claiming, holder);
-
-	/*
-	 * Block event polling for write claims if requested.  Any write holder
-	 * makes the write_holder state stick until all are released.  This is
-	 * good enough and tracking individual writeable reference is too
-	 * fragile given the way @mode is used in blkdev_get/put().
-	 */
-	if (claiming && (mode & FMODE_WRITE) && !bdev->bd_write_holder &&
-	    (disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE)) {
-		bdev->bd_write_holder = true;
-		unblock_events = false;
-	}
-	mutex_unlock(&bdev->bd_mutex);
-
-	if (unblock_events)
-		disk_unblock_events(disk);
-
-	/* only one opener holds refs to the module and disk */
-	if (!first_open)
-		put_disk_and_module(disk);
-	if (whole)
-		bdput(whole);
 	return 0;
-
- out_clear:
-	disk_put_part(bdev->bd_part);
-	bdev->bd_disk = NULL;
-	bdev->bd_part = NULL;
-	if (bdev != bdev->bd_contains)
-		__blkdev_put(bdev->bd_contains, mode, 1);
-	bdev->bd_contains = NULL;
- out_unlock_bdev:
-	if (claiming)
-		bd_abort_claiming(bdev, claiming, holder);
-	mutex_unlock(&bdev->bd_mutex);
-	disk_unblock_events(disk);
- out_put_whole:
- 	if (whole)
-		bdput(whole);
- out_put_disk:
-	put_disk_and_module(disk);
-	if (need_restart)
-		goto restart;
- out:
-	return ret;
 }
 
-/**
- * blkdev_get - open a block device
- * @bdev: block_device to open
- * @mode: FMODE_* mask
- * @holder: exclusive holder identifier
- *
- * Open @bdev with @mode.  If @mode includes %FMODE_EXCL, @bdev is
- * open with exclusive access.  Specifying %FMODE_EXCL with %NULL
- * @holder is invalid.  Exclusive opens may nest for the same @holder.
- *
- * On success, the reference count of @bdev is unchanged.  On failure,
- * @bdev is put.
- *
- * CONTEXT:
- * Might sleep.
- *
- * RETURNS:
- * 0 on success, -errno on failure.
- */
-static int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder)
-{
-	int ret, perm = 0;
-
-	if (mode & FMODE_READ)
-		perm |= MAY_READ;
-	if (mode & FMODE_WRITE)
-		perm |= MAY_WRITE;
-	ret = devcgroup_inode_permission(bdev->bd_inode, perm);
-	if (ret)
-		goto bdput;
-
-	ret =__blkdev_get(bdev, mode, holder, 0);
-	if (ret)
-		goto bdput;
-	return 0;
-
-bdput:
-	bdput(bdev);
-	return ret;
-}
-
-/**
- * blkdev_get_by_path - open a block device by name
- * @path: path to the block device to open
- * @mode: FMODE_* mask
- * @holder: exclusive holder identifier
- *
- * Open the blockdevice described by the device file at @path.  @mode
- * and @holder are identical to blkdev_get().
- *
- * On success, the returned block_device has reference count of one.
- *
- * CONTEXT:
- * Might sleep.
- *
- * RETURNS:
- * Pointer to block_device on success, ERR_PTR(-errno) on failure.
- */
-struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
-					void *holder)
+struct block_device *blkdev_get_no_open(dev_t dev)
 {
 	struct block_device *bdev;
-	int err;
+	struct gendisk *disk;
 
-	bdev = lookup_bdev(path);
-	if (IS_ERR(bdev))
-		return bdev;
+	down_read(&bdev_lookup_sem);
+	bdev = bdget(dev);
+	if (!bdev) {
+		up_read(&bdev_lookup_sem);
+		blk_request_module(dev);
+		down_read(&bdev_lookup_sem);
 
-	err = blkdev_get(bdev, mode, holder);
-	if (err)
-		return ERR_PTR(err);
-
-	if ((mode & FMODE_WRITE) && bdev_read_only(bdev)) {
-		blkdev_put(bdev, mode);
-		return ERR_PTR(-EACCES);
+		bdev = bdget(dev);
+		if (!bdev)
+			goto unlock;
 	}
 
+	disk = bdev->bd_disk;
+	if (!kobject_get_unless_zero(&disk_to_dev(disk)->kobj))
+		goto bdput;
+	if ((disk->flags & (GENHD_FL_UP | GENHD_FL_HIDDEN)) != GENHD_FL_UP)
+		goto put_disk;
+	if (!try_module_get(bdev->bd_disk->fops->owner))
+		goto put_disk;
+	up_read(&bdev_lookup_sem);
 	return bdev;
+put_disk:
+	put_disk(disk);
+bdput:
+	bdput(bdev);
+unlock:
+	up_read(&bdev_lookup_sem);
+	return NULL;
 }
-EXPORT_SYMBOL(blkdev_get_by_path);
+
+void blkdev_put_no_open(struct block_device *bdev)
+{
+	module_put(bdev->bd_disk->fops->owner);
+	put_disk(bdev->bd_disk);
+	bdput(bdev);
+}
 
 /**
  * blkdev_get_by_dev - open a block device by device number
···
  * @mode: FMODE_* mask
  * @holder: exclusive holder identifier
  *
- * Open the blockdevice described by device number @dev.  @mode and
- * @holder are identical to blkdev_get().
+ * Open the block device described by device number @dev. If @mode includes
+ * %FMODE_EXCL, the block device is opened with exclusive access.  Specifying
+ * %FMODE_EXCL with a %NULL @holder is invalid.  Exclusive opens may nest for
+ * the same @holder.
  *
- * Use it ONLY if you really do not have anything better - i.e. when
- * you are behind a truly sucky interface and all you are given is a
- * device number.  _Never_ to be used for internal purposes.  If you
- * ever need it - reconsider your API.
- *
- * On success, the returned block_device has reference count of one.
+ * Use this interface ONLY if you really do not have anything better - i.e. when
+ * you are behind a truly sucky interface and all you are given is a device
+ * number.  Everything else should use blkdev_get_by_path().
  *
  * CONTEXT:
  * Might sleep.
  *
  * RETURNS:
- * Pointer to block_device on success, ERR_PTR(-errno) on failure.
+ * Reference to the block_device on success, ERR_PTR(-errno) on failure.
  */
 struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder)
 {
+	bool unblock_events = true;
 	struct block_device *bdev;
-	int err;
+	struct gendisk *disk;
+	int ret;
 
-	bdev = bdget(dev);
+	ret = devcgroup_check_permission(DEVCG_DEV_BLOCK,
+			MAJOR(dev), MINOR(dev),
+			((mode & FMODE_READ) ? DEVCG_ACC_READ : 0) |
+			((mode & FMODE_WRITE) ? DEVCG_ACC_WRITE : 0));
+	if (ret)
+		return ERR_PTR(ret);
+
+	/*
+	 * If we lost a race with 'disk' being deleted, try again.  See md.c.
+	 */
+retry:
+	bdev = blkdev_get_no_open(dev);
 	if (!bdev)
-		return ERR_PTR(-ENOMEM);
+		return ERR_PTR(-ENXIO);
+	disk = bdev->bd_disk;
 
-	err = blkdev_get(bdev, mode, holder);
-	if (err)
-		return ERR_PTR(err);
+	if (mode & FMODE_EXCL) {
+		ret = bd_prepare_to_claim(bdev, holder);
+		if (ret)
+			goto put_blkdev;
+	}
+
+	disk_block_events(disk);
+
+	mutex_lock(&bdev->bd_mutex);
+	ret =__blkdev_get(bdev, mode);
+	if (ret)
+		goto abort_claiming;
+	if (mode & FMODE_EXCL) {
+		bd_finish_claiming(bdev, holder);
+
+		/*
+		 * Block event polling for write claims if requested.  Any write
+		 * holder makes the write_holder state stick until all are
+		 * released.  This is good enough and tracking individual
+		 * writeable reference is too fragile given the way @mode is
+		 * used in blkdev_get/put().
+		 */
+		if ((mode & FMODE_WRITE) && !bdev->bd_write_holder &&
+		    (disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE)) {
+			bdev->bd_write_holder = true;
+			unblock_events = false;
+		}
+	}
+	mutex_unlock(&bdev->bd_mutex);
+
+	if (unblock_events)
+		disk_unblock_events(disk);
+	return bdev;
+
+abort_claiming:
+	if (mode & FMODE_EXCL)
+		bd_abort_claiming(bdev, holder);
+	mutex_unlock(&bdev->bd_mutex);
+	disk_unblock_events(disk);
+put_blkdev:
+	blkdev_put_no_open(bdev);
+	if (ret == -ERESTARTSYS)
+		goto retry;
+	return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(blkdev_get_by_dev);
+
+/**
+ * blkdev_get_by_path - open a block device by name
+ * @path: path to the block device to open
+ * @mode: FMODE_* mask
+ * @holder: exclusive holder identifier
+ *
+ * Open the block device described by the device file at @path.  If @mode
+ * includes %FMODE_EXCL, the block device is opened with exclusive access.
+ * Specifying %FMODE_EXCL with a %NULL @holder is invalid.  Exclusive opens may
+ * nest for the same @holder.
+ *
+ * CONTEXT:
+ * Might sleep.
+ *
+ * RETURNS:
+ * Reference to the block_device on success, ERR_PTR(-errno) on failure.
+ */
+struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
+					void *holder)
+{
+	struct block_device *bdev;
+	dev_t dev;
+	int error;
+
+	error = lookup_bdev(path, &dev);
+	if (error)
+		return ERR_PTR(error);
+
+	bdev = blkdev_get_by_dev(dev, mode, holder);
+	if (!IS_ERR(bdev) && (mode & FMODE_WRITE) && bdev_read_only(bdev)) {
+		blkdev_put(bdev, mode);
+		return ERR_PTR(-EACCES);
+	}
 
 	return bdev;
 }
-EXPORT_SYMBOL(blkdev_get_by_dev);
+EXPORT_SYMBOL(blkdev_get_by_path);
 
 static int blkdev_open(struct inode * inode, struct file * filp)
 {
···
 	if ((filp->f_flags & O_ACCMODE) == 3)
 		filp->f_mode |= FMODE_WRITE_IOCTL;
 
-	bdev = bd_acquire(inode);
-	if (bdev == NULL)
-		return -ENOMEM;
-
+	bdev = blkdev_get_by_dev(inode->i_rdev, filp->f_mode, filp);
+	if (IS_ERR(bdev))
+		return PTR_ERR(bdev);
 	filp->f_mapping = bdev->bd_inode->i_mapping;
 	filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
-
-	return blkdev_get(bdev, filp->f_mode, filp);
+	return 0;
 }
 
 static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
···
 		WARN_ON_ONCE(bdev->bd_holders);
 		sync_blockdev(bdev);
 		kill_bdev(bdev);
-
 		bdev_write_inode(bdev);
+		if (bdev_is_partition(bdev))
+			victim = bdev_whole(bdev);
 	}
-	if (bdev->bd_contains == bdev) {
-		if (disk->fops->release)
-			disk->fops->release(disk, mode);
-	}
-	if (!bdev->bd_openers) {
-		disk_put_part(bdev->bd_part);
-		bdev->bd_part = NULL;
-		bdev->bd_disk = NULL;
-		if (bdev != bdev->bd_contains)
-			victim = bdev->bd_contains;
-		bdev->bd_contains = NULL;
 
-		put_disk_and_module(disk);
-	}
+	if (!bdev_is_partition(bdev) && disk->fops->release)
+		disk->fops->release(disk, mode);
 	mutex_unlock(&bdev->bd_mutex);
-	bdput(bdev);
-	if (victim)
+	if (victim) {
 		__blkdev_put(victim, mode, 1);
+		bdput(victim);
+	}
 }
 
 void blkdev_put(struct block_device *bdev, fmode_t mode)
 {
+	struct gendisk *disk = bdev->bd_disk;
+
 	mutex_lock(&bdev->bd_mutex);
 
 	if (mode & FMODE_EXCL) {
+		struct block_device *whole = bdev_whole(bdev);
 		bool bdev_free;
 
 		/*
···
 		spin_lock(&bdev_lock);
 
 		WARN_ON_ONCE(--bdev->bd_holders < 0);
-		WARN_ON_ONCE(--bdev->bd_contains->bd_holders < 0);
+		WARN_ON_ONCE(--whole->bd_holders < 0);
 
-		/* bd_contains might point to self, check in a separate step */
 		if ((bdev_free = !bdev->bd_holders))
 			bdev->bd_holder = NULL;
-		if (!bdev->bd_contains->bd_holders)
-			bdev->bd_contains->bd_holder = NULL;
+		if (!whole->bd_holders)
+			whole->bd_holder = NULL;
 
 		spin_unlock(&bdev_lock);
 
···
 		 * unblock evpoll if it was a write holder.
 		 */
 		if (bdev_free && bdev->bd_write_holder) {
-			disk_unblock_events(bdev->bd_disk);
+			disk_unblock_events(disk);
 			bdev->bd_write_holder = false;
 		}
 	}
···
 	 * event.  This is to ensure detection of media removal commanded
 	 * from userland - e.g. eject(1).
 	 */
-	disk_flush_events(bdev->bd_disk, DISK_EVENT_MEDIA_CHANGE);
-
+	disk_flush_events(disk, DISK_EVENT_MEDIA_CHANGE);
 	mutex_unlock(&bdev->bd_mutex);
 
 	__blkdev_put(bdev, mode, 0);
+	blkdev_put_no_open(bdev);
 }
 EXPORT_SYMBOL(blkdev_put);
 
···
  * namespace if possible and return it.  Return ERR_PTR(error)
  * otherwise.
  */
-struct block_device *lookup_bdev(const char *pathname)
+int lookup_bdev(const char *pathname, dev_t *dev)
 {
-	struct block_device *bdev;
 	struct inode *inode;
 	struct path path;
 	int error;
 
 	if (!pathname || !*pathname)
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 
 	error = kern_path(pathname, LOOKUP_FOLLOW, &path);
 	if (error)
-		return ERR_PTR(error);
+		return error;
 
 	inode = d_backing_inode(path.dentry);
 	error = -ENOTBLK;
 	if (!S_ISBLK(inode->i_mode))
-		goto fail;
+		goto out_path_put;
 	error = -EACCES;
 	if (!may_open_dev(&path))
-		goto fail;
-	error = -ENOMEM;
-	bdev = bd_acquire(inode);
-	if (!bdev)
-		goto fail;
-out:
+		goto out_path_put;
+
+	*dev = inode->i_rdev;
+	error = 0;
+out_path_put:
 	path_put(&path);
-	return bdev;
-fail:
-	bdev = ERR_PTR(error);
-	goto out;
+	return error;
 }
 EXPORT_SYMBOL(lookup_bdev);
 

fs/btrfs/sysfs.c

···
 
 void btrfs_sysfs_remove_device(struct btrfs_device *device)
 {
-	struct hd_struct *disk;
-	struct kobject *disk_kobj;
 	struct kobject *devices_kobj;
 
 	/*
···
 	devices_kobj = device->fs_info->fs_devices->devices_kobj;
 	ASSERT(devices_kobj);
 
-	if (device->bdev) {
-		disk = device->bdev->bd_part;
-		disk_kobj = &part_to_dev(disk)->kobj;
-		sysfs_remove_link(devices_kobj, disk_kobj->name);
-	}
+	if (device->bdev)
+		sysfs_remove_link(devices_kobj, bdev_kobj(device->bdev)->name);
 
 	if (device->devid_kobj.state_initialized) {
 		kobject_del(&device->devid_kobj);
···
 	nofs_flag = memalloc_nofs_save();
 
 	if (device->bdev) {
-		struct hd_struct *disk;
-		struct kobject *disk_kobj;
-
-		disk = device->bdev->bd_part;
-		disk_kobj = &part_to_dev(disk)->kobj;
+		struct kobject *disk_kobj = bdev_kobj(device->bdev);
 
 		ret = sysfs_create_link(devices_kobj, disk_kobj, disk_kobj->name);
 		if (ret) {

fs/btrfs/volumes.c

···
 		 * make sure it's the same device if the device is mounted
 		 */
 		if (device->bdev) {
-			struct block_device *path_bdev;
+			int error;
+			dev_t path_dev;
 
-			path_bdev = lookup_bdev(path);
-			if (IS_ERR(path_bdev)) {
+			error = lookup_bdev(path, &path_dev);
+			if (error) {
 				mutex_unlock(&fs_devices->device_list_mutex);
-				return ERR_CAST(path_bdev);
+				return ERR_PTR(error);
 			}
 
-			if (device->bdev != path_bdev) {
-				bdput(path_bdev);
+			if (device->bdev->bd_dev != path_dev) {
 				mutex_unlock(&fs_devices->device_list_mutex);
 				/*
 				 * device->fs_info may not be reliable here, so
···
 						  task_pid_nr(current));
 				return ERR_PTR(-EEXIST);
 			}
-			bdput(path_bdev);
 			btrfs_info_in_rcu(device->fs_info,
 	"devid %llu device path %s changed to %s scanned by %s (%d)",
 					  devid, rcu_str_deref(device->name),

fs/btrfs/zoned.c

···
 	if (!zone_info)
 		return -ENOMEM;
 
-	nr_sectors = bdev->bd_part->nr_sects;
+	nr_sectors = bdev_nr_sectors(bdev);
 	zone_sectors = bdev_zone_sectors(bdev);
 	/* Check if it's power of 2 (see is_power_of_2) */
 	ASSERT(zone_sectors != 0 && (zone_sectors & (zone_sectors - 1)) == 0);
···
 		return -EINVAL;
 	zone_size = zone_sectors << SECTOR_SHIFT;
 	zone_sectors_shift = ilog2(zone_sectors);
-	nr_sectors = bdev->bd_part->nr_sects;
+	nr_sectors = bdev_nr_sectors(bdev);
 	nr_zones = nr_sectors >> zone_sectors_shift;
 
 	sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
···
 
 	zone_sectors = bdev_zone_sectors(bdev);
 	zone_sectors_shift = ilog2(zone_sectors);
-	nr_sectors = bdev->bd_part->nr_sects;
+	nr_sectors = bdev_nr_sectors(bdev);
 	nr_zones = nr_sectors >> zone_sectors_shift;
 
 	sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);

fs/buffer.c

···
 
 void emergency_thaw_bdev(struct super_block *sb)
 {
-	while (sb->s_bdev && !thaw_bdev(sb->s_bdev, sb))
+	while (sb->s_bdev && !thaw_bdev(sb->s_bdev))
 		printk(KERN_WARNING "Emergency Thaw on %pg\n", sb->s_bdev);
 }
 

fs/ext4/ioctl.c

···
 	case EXT4_GOING_FLAGS_DEFAULT:
 		freeze_bdev(sb->s_bdev);
 		set_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);
-		thaw_bdev(sb->s_bdev, sb);
+		thaw_bdev(sb->s_bdev);
 		break;
 	case EXT4_GOING_FLAGS_LOGFLUSH:
 		set_bit(EXT4_FLAGS_SHUTDOWN, &sbi->s_ext4_flags);

fs/ext4/super.c

···
 	sbi->s_sb = sb;
 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
 	sbi->s_sb_block = sb_block;
-	if (sb->s_bdev->bd_part)
-		sbi->s_sectors_written_start =
-			part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
+	sbi->s_sectors_written_start =
+		part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
 
 	/* Cleanup superblock name */
 	strreplace(sb->s_id, '/', '!');
···
 	 */
 	if (!(sb->s_flags & SB_RDONLY))
 		ext4_update_tstamp(es, s_wtime);
-	if (sb->s_bdev->bd_part)
-		es->s_kbytes_written =
-			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
-			    ((part_stat_read(sb->s_bdev->bd_part,
-					     sectors[STAT_WRITE]) -
-			      EXT4_SB(sb)->s_sectors_written_start) >> 1));
-	else
-		es->s_kbytes_written =
-			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
+	es->s_kbytes_written =
+		cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
+		    ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
+		      EXT4_SB(sb)->s_sectors_written_start) >> 1));
 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
 		ext4_free_blocks_count_set(es,
 			EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(

fs/ext4/sysfs.c

···
 {
 	struct super_block *sb = sbi->s_buddy_cache->i_sb;
 
-	if (!sb->s_bdev->bd_part)
-		return snprintf(buf, PAGE_SIZE, "0\n");
 	return snprintf(buf, PAGE_SIZE, "%lu\n",
-			(part_stat_read(sb->s_bdev->bd_part,
-					sectors[STAT_WRITE]) -
+			(part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 			 sbi->s_sectors_written_start) >> 1);
 }
 
···
 {
 	struct super_block *sb = sbi->s_buddy_cache->i_sb;
 
-	if (!sb->s_bdev->bd_part)
-		return snprintf(buf, PAGE_SIZE, "0\n");
 	return snprintf(buf, PAGE_SIZE, "%llu\n",
 			(unsigned long long)(sbi->s_kbytes_written +
-			((part_stat_read(sb->s_bdev->bd_part,
-					 sectors[STAT_WRITE]) -
+			((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
 			  EXT4_SB(sb)->s_sectors_written_start) >> 1)));
 }
 

fs/f2fs/checkpoint.c

···
 	__u32 crc32 = 0;
 	int i;
 	int cp_payload_blks = __cp_payload(sbi);
-	struct super_block *sb = sbi->sb;
 	struct curseg_info *seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);
 	u64 kbytes_written;
 	int err;
···
 	start_blk += data_sum_blocks;
 
 	/* Record write statistics in the hot node summary */
-	kbytes_written = sbi->kbytes_written;
-	if (sb->s_bdev->bd_part)
-		kbytes_written += BD_PART_WRITTEN(sbi);
+	kbytes_written = sbi->kbytes_written + BD_PART_WRITTEN(sbi);
 
 	seg_i->journal->info.kbytes_written = cpu_to_le64(kbytes_written);
 

fs/f2fs/f2fs.h

···
  * and the return value is in kbytes. s is of struct f2fs_sb_info.
  */
 #define BD_PART_WRITTEN(s)						 \
-(((u64)part_stat_read((s)->sb->s_bdev->bd_part, sectors[STAT_WRITE]) -   \
+	(((u64)part_stat_read((s)->sb->s_bdev, sectors[STAT_WRITE]) -   \
 		(s)->sectors_written_start) >> 1)
 
 static inline void f2fs_update_time(struct f2fs_sb_info *sbi, int type)

fs/f2fs/file.c

···
 
 	switch (in) {
 	case F2FS_GOING_DOWN_FULLSYNC:
-		sb = freeze_bdev(sb->s_bdev);
-		if (IS_ERR(sb)) {
-			ret = PTR_ERR(sb);
+		ret = freeze_bdev(sb->s_bdev);
+		if (ret)
 			goto out;
-		}
-		if (sb) {
-			f2fs_stop_checkpoint(sbi, false);
-			set_sbi_flag(sbi, SBI_IS_SHUTDOWN);
-			thaw_bdev(sb->s_bdev, sb);
-		}
+		f2fs_stop_checkpoint(sbi, false);
+		set_sbi_flag(sbi, SBI_IS_SHUTDOWN);
+		thaw_bdev(sb->s_bdev);
 		break;
 	case F2FS_GOING_DOWN_METASYNC:
 		/* do checkpoint only */

fs/f2fs/super.c

···
 static int init_blkz_info(struct f2fs_sb_info *sbi, int devi)
 {
 	struct block_device *bdev = FDEV(devi).bdev;
-	sector_t nr_sectors = bdev->bd_part->nr_sects;
+	sector_t nr_sectors = bdev_nr_sectors(bdev);
 	struct f2fs_report_zones_args rep_zone_arg;
 	int ret;
 
···
 	}
 
 	/* For write statistics */
-	if (sb->s_bdev->bd_part)
-		sbi->sectors_written_start =
-			(u64)part_stat_read(sb->s_bdev->bd_part,
-					    sectors[STAT_WRITE]);
+	sbi->sectors_written_start =
+		(u64)part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
 
 	/* Read accumulated write IO statistics if exists */
 	seg_i = CURSEG_I(sbi, CURSEG_HOT_NODE);

fs/f2fs/sysfs.c

···
 static ssize_t lifetime_write_kbytes_show(struct f2fs_attr *a,
 		struct f2fs_sb_info *sbi, char *buf)
 {
-	struct super_block *sb = sbi->sb;
-
-	if (!sb->s_bdev->bd_part)
-		return sprintf(buf, "0\n");
-
 	return sprintf(buf, "%llu\n",
 			(unsigned long long)(sbi->kbytes_written +
 			BD_PART_WRITTEN(sbi)));
···
 static ssize_t features_show(struct f2fs_attr *a,
 		struct f2fs_sb_info *sbi, char *buf)
 {
-	struct super_block *sb = sbi->sb;
 	int len = 0;
-
-	if (!sb->s_bdev->bd_part)
-		return sprintf(buf, "0\n");
 
 	if (f2fs_sb_has_encrypt(sbi))
 		len += scnprintf(buf, PAGE_SIZE - len, "%s",

fs/inode.c

···
 	inode->i_bytes = 0;
 	inode->i_generation = 0;
 	inode->i_pipe = NULL;
-	inode->i_bdev = NULL;
 	inode->i_cdev = NULL;
 	inode->i_link = NULL;
 	inode->i_dir_seq = 0;
···
 		truncate_inode_pages_final(&inode->i_data);
 		clear_inode(inode);
 	}
-	if (S_ISBLK(inode->i_mode) && inode->i_bdev)
-		bd_forget(inode);
 	if (S_ISCHR(inode->i_mode) && inode->i_cdev)
 		cd_forget(inode);
 

fs/internal.h

···
 extern int __sync_blockdev(struct block_device *bdev, int wait);
 void iterate_bdevs(void (*)(struct block_device *, void *), void *);
 void emergency_thaw_bdev(struct super_block *sb);
-void bd_forget(struct inode *inode);
 #else
 static inline void bdev_cache_init(void)
 {
···
 static inline int emergency_thaw_bdev(struct super_block *sb)
 {
 	return 0;
-}
-static inline void bd_forget(struct inode *inode)
-{
 }
 #endif /* CONFIG_BLOCK */
 
···
  */
 extern int reconfigure_super(struct fs_context *);
 extern bool trylock_super(struct super_block *sb);
-extern struct super_block *user_get_super(dev_t);
+struct super_block *user_get_super(dev_t, bool excl);
+void put_super(struct super_block *sb);
 extern bool mount_capable(struct fs_context *);
 
 /*

fs/io_uring.c

···
 
 static bool io_bdev_nowait(struct block_device *bdev)
 {
-#ifdef CONFIG_BLOCK
 	return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
-#else
-	return true;
-#endif
 }
 
 /*
···
 	umode_t mode = file_inode(file)->i_mode;
 
 	if (S_ISBLK(mode)) {
-		if (io_bdev_nowait(file->f_inode->i_bdev))
+		if (IS_ENABLED(CONFIG_BLOCK) &&
+		    io_bdev_nowait(I_BDEV(file->f_mapping->host)))
 			return true;
 		return false;
 	}
 	if (S_ISCHR(mode) || S_ISSOCK(mode))
 		return true;
 	if (S_ISREG(mode)) {
-		if (io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
+		if (IS_ENABLED(CONFIG_BLOCK) &&
+		    io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
 		    file->f_op != &io_uring_fops)
 			return true;
 		return false;

fs/pipe.c

···
 }
 
 /*
- * After the inode slimming patch, i_pipe/i_bdev/i_cdev share the same
- * location, so checking ->i_pipe is not enough to verify that this is a
- * pipe.
+ * Note that i_pipe and i_cdev share the same location, so checking ->i_pipe is
+ * not enough to verify that this is a pipe.
  */
 struct pipe_inode_info *get_pipe_info(struct file *file, bool for_splice)
 {

fs/pstore/blk.c

···
 			return bdev;
 	}
 
-	nr_sects = part_nr_sects_read(bdev->bd_part);
+	nr_sects = bdev_nr_sectors(bdev);
 	if (!nr_sects) {
 		pr_err("not enough space for '%s'\n", blkdev);
 		blkdev_put(bdev, mode);

fs/quota/quota.c

···
 #include <linux/writeback.h>
 #include <linux/nospec.h>
 #include "compat.h"
+#include "../internal.h"
 
 static int check_quotactl_permission(struct super_block *sb, int type, int cmd,
 				     qid_t id)
···
 static struct super_block *quotactl_block(const char __user *special, int cmd)
 {
 #ifdef CONFIG_BLOCK
-	struct block_device *bdev;
 	struct super_block *sb;
 	struct filename *tmp = getname(special);
+	bool excl = false, thawed = false;
+	int error;
+	dev_t dev;
 
 	if (IS_ERR(tmp))
 		return ERR_CAST(tmp);
-	bdev = lookup_bdev(tmp->name);
+	error = lookup_bdev(tmp->name, &dev);
 	putname(tmp);
-	if (IS_ERR(bdev))
-		return ERR_CAST(bdev);
-	if (quotactl_cmd_onoff(cmd))
-		sb = get_super_exclusive_thawed(bdev);
-	else if (quotactl_cmd_write(cmd))
-		sb = get_super_thawed(bdev);
-	else
-		sb = get_super(bdev);
-	bdput(bdev);
+	if (error)
+		return ERR_PTR(error);
+
+	if (quotactl_cmd_onoff(cmd)) {
+		excl = true;
+		thawed = true;
+	} else if (quotactl_cmd_write(cmd)) {
+		thawed = true;
+	}
+
+retry:
+	sb = user_get_super(dev, excl);
 	if (!sb)
 		return ERR_PTR(-ENODEV);
-
+	if (thawed && sb->s_writers.frozen != SB_UNFROZEN) {
+		if (excl)
+			up_write(&sb->s_umount);
+		else
+			up_read(&sb->s_umount);
+		wait_event(sb->s_writers.wait_unfrozen,
+			   sb->s_writers.frozen == SB_UNFROZEN);
+		put_super(sb);
+		goto retry;
+	}
 	return sb;
+
 #else
 	return ERR_PTR(-ENODEV);
 #endif

fs/statfs.c

···
 
 static int vfs_ustat(dev_t dev, struct kstatfs *sbuf)
 {
-	struct super_block *s = user_get_super(dev);
+	struct super_block *s = user_get_super(dev, false);
 	int err;
 	if (!s)
 		return -EINVAL;

fs/super.c

···
  *	Drops a temporary reference, frees superblock if there's no
  *	references left.
  */
-static void put_super(struct super_block *sb)
+void put_super(struct super_block *sb)
 {
 	spin_lock(&sb_lock);
 	__put_super(sb);
···
 
 EXPORT_SYMBOL(iterate_supers_type);
 
-static struct super_block *__get_super(struct block_device *bdev, bool excl)
+/**
+ * get_super - get the superblock of a device
+ * @bdev: device to get the superblock for
+ *
+ * Scans the superblock list and finds the superblock of the file system
+ * mounted on the device given. %NULL is returned if no match is found.
+ */
+struct super_block *get_super(struct block_device *bdev)
 {
 	struct super_block *sb;
 
···
 		if (sb->s_bdev == bdev) {
 			sb->s_count++;
 			spin_unlock(&sb_lock);
-			if (!excl)
-				down_read(&sb->s_umount);
-			else
-				down_write(&sb->s_umount);
+			down_read(&sb->s_umount);
 			/* still alive? */
 			if (sb->s_root && (sb->s_flags & SB_BORN))
 				return sb;
-			if (!excl)
-				up_read(&sb->s_umount);
-			else
-				up_write(&sb->s_umount);
+			up_read(&sb->s_umount);
 			/* nope, got unmounted */
 			spin_lock(&sb_lock);
 			__put_super(sb);
···
 	spin_unlock(&sb_lock);
 	return NULL;
 }
-
-/**
- *	get_super - get the superblock of a device
- *	@bdev: device to get the superblock for
- *
- *	Scans the superblock list and finds the superblock of the file system
- *	mounted on the device given. %NULL is returned if no match is found.
- */
-struct super_block *get_super(struct block_device *bdev)
-{
-	return __get_super(bdev, false);
-}
-EXPORT_SYMBOL(get_super);
-
-static struct super_block *__get_super_thawed(struct block_device *bdev,
-					      bool excl)
-{
-	while (1) {
-		struct super_block *s = __get_super(bdev, excl);
-		if (!s || s->s_writers.frozen == SB_UNFROZEN)
-			return s;
-		if (!excl)
-			up_read(&s->s_umount);
-		else
-			up_write(&s->s_umount);
-		wait_event(s->s_writers.wait_unfrozen,
-			   s->s_writers.frozen == SB_UNFROZEN);
-		put_super(s);
-	}
-}
-
-/**
- *	get_super_thawed - get thawed superblock of a device
- *	@bdev: device to get the superblock for
- *
- *	Scans the superblock list and finds the superblock of the file system
- *	mounted on the device. The superblock is returned once it is thawed
- *	(or immediately if it was not frozen). %NULL is returned if no match
- *	is found.
- */
-struct super_block *get_super_thawed(struct block_device *bdev)
-{
-	return __get_super_thawed(bdev, false);
-}
-EXPORT_SYMBOL(get_super_thawed);
-
-/**
- *	get_super_exclusive_thawed - get thawed superblock of a device
- *	@bdev: device to get the superblock for
- *
- *	Scans the superblock list and finds the superblock of the file system
- *	mounted on the device. The superblock is returned once it is thawed
- *	(or immediately if it was not frozen) and s_umount semaphore is held
- *	in exclusive mode. %NULL is returned if no match is found.
- */
-struct super_block *get_super_exclusive_thawed(struct block_device *bdev)
-{
-	return __get_super_thawed(bdev, true);
-}
-EXPORT_SYMBOL(get_super_exclusive_thawed);
 
 /**
  * get_active_super - get an active reference to the superblock of a device
···
 	return NULL;
 }
 
-struct super_block *user_get_super(dev_t dev)
+struct super_block *user_get_super(dev_t dev, bool excl)
 {
 	struct super_block *sb;
 
···
 		if (sb->s_dev ==  dev) {
 			sb->s_count++;
 			spin_unlock(&sb_lock);
-			down_read(&sb->s_umount);
+			if (excl)
+				down_write(&sb->s_umount);
+			else
+				down_read(&sb->s_umount);
 			/* still alive? */
 			if (sb->s_root && (sb->s_flags & SB_BORN))
 				return sb;
-			up_read(&sb->s_umount);
+			if (excl)
+				up_write(&sb->s_umount);
+			else
+				up_read(&sb->s_umount);
 			/* nope, got unmounted */
 			spin_lock(&sb_lock);
 			__put_super(sb);

fs/xfs/xfs_fsops.c

···
 {
 	switch (inflags) {
 	case XFS_FSOP_GOING_FLAGS_DEFAULT: {
-		struct super_block *sb = freeze_bdev(mp->m_super->s_bdev);
-
-		if (sb && !IS_ERR(sb)) {
+		if (!freeze_bdev(mp->m_super->s_bdev)) {
 			xfs_force_shutdown(mp, SHUTDOWN_FORCE_UMOUNT);
-			thaw_bdev(sb->s_bdev, sb);
+			thaw_bdev(mp->m_super->s_bdev);
 		}
-
 		break;
 	}
 	case XFS_FSOP_GOING_FLAGS_LOGFLUSH:

include/linux/bio.h

···
 		/* TODO: It is reasonable to complete bio with error here. */
 }
 
+/* @bytes should be less or equal to bvec[i->bi_idx].bv_len */
+static inline void bio_advance_iter_single(const struct bio *bio,
+					   struct bvec_iter *iter,
+					   unsigned int bytes)
+{
+	iter->bi_sector += bytes >> 9;
+
+	if (bio_no_advance_iter(bio))
+		iter->bi_size -= bytes;
+	else
+		bvec_iter_advance_single(bio->bi_io_vec, iter, bytes);
+}
+
 #define __bio_for_each_segment(bvl, bio, iter, start)			\
 	for (iter = (start);						\
 	     (iter).bi_size &&						\
 		((bvl = bio_iter_iovec((bio), (iter))), 1);		\
-	     bio_advance_iter((bio), &(iter), (bvl).bv_len))
+	     bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
 
 #define bio_for_each_segment(bvl, bio, iter)				\
 	__bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
···
 	for (iter = (start);						\
 	     (iter).bi_size &&						\
 		((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \
-	     bio_advance_iter((bio), &(iter), (bvl).bv_len))
+	     bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
 
 /* iterate over multi-page bvec */
 #define bio_for_each_bvec(bvl, bio, iter)			\
···
 {
 	return bs->bio_slab != NULL;
 }
-
-/*
- * a small number of entries is fine, not going to be performance critical.
- * basically we just need to survive
- */
-#define BIO_SPLIT_ENTRIES 2
 
 #if defined(CONFIG_BLK_DEV_INTEGRITY)
 

include/linux/blk-cgroup.h

···
 u64 __blkg_prfill_u64(struct seq_file *sf, struct blkg_policy_data *pd, u64 v);
 
 struct blkg_conf_ctx {
-	struct gendisk			*disk;
+	struct block_device		*bdev;
 	struct blkcg_gq			*blkg;
 	char				*body;
 };
 
-struct gendisk *blkcg_conf_get_disk(char **inputp);
+struct block_device *blkcg_conf_open_bdev(char **inputp);
 int blkg_conf_prep(struct blkcg *blkcg, const struct blkcg_policy *pol,
 		   char *input, struct blkg_conf_ctx *ctx);
 void blkg_conf_finish(struct blkg_conf_ctx *ctx);

include/linux/blk-mq.h

···
 #include <linux/blkdev.h>
 #include <linux/sbitmap.h>
 #include <linux/srcu.h>
+#include <linux/lockdep.h>
 
 struct blk_mq_tags;
 struct blk_flush_queue;
···
 }
 
 blk_qc_t blk_mq_submit_bio(struct bio *bio);
+void blk_mq_hctx_set_fq_lock_class(struct blk_mq_hw_ctx *hctx,
+		struct lock_class_key *key);
 
 #endif

include/linux/blk_types.h

···
 
 #include <linux/types.h>
 #include <linux/bvec.h>
+#include <linux/device.h>
 #include <linux/ktime.h>
 
 struct bio_set;
···
 struct bio_crypt_ctx;
 
 struct block_device {
+	sector_t		bd_start_sect;
+	struct disk_stats __percpu *bd_stats;
+	unsigned long		bd_stamp;
+	bool			bd_read_only;	/* read-only policy */
 	dev_t			bd_dev;
 	int			bd_openers;
 	struct inode *		bd_inode;	/* will die */
 	struct super_block *	bd_super;
 	struct mutex		bd_mutex;	/* open/close mutex */
 	void *			bd_claiming;
+	struct device		bd_device;
 	void *			bd_holder;
 	int			bd_holders;
 	bool			bd_write_holder;
 #ifdef CONFIG_SYSFS
 	struct list_head	bd_holder_disks;
 #endif
-	struct block_device *	bd_contains;
+	struct kobject		*bd_holder_dir;
 	u8			bd_partno;
-	struct hd_struct *	bd_part;
 	/* number of times partitions within this device have been opened. */
 	unsigned		bd_part_count;
 
···
 	int			bd_fsfreeze_count;
 	/* Mutex for freeze */
 	struct mutex		bd_fsfreeze_mutex;
+	struct super_block	*bd_fsfreeze_sb;
+
+	struct partition_meta_info *bd_meta_info;
+#ifdef CONFIG_FAIL_MAKE_REQUEST
+	bool			bd_make_it_fail;
+#endif
 } __randomize_layout;
+
+#define bdev_whole(_bdev) \
+	((_bdev)->bd_disk->part0)
+
+#define dev_to_bdev(device) \
+	container_of((device), struct block_device, bd_device)
+
+#define bdev_kobj(_bdev) \
+	(&((_bdev)->bd_device.kobj))
 
 /*
  * Block error status values.  See block/blk-core:blk_errors for the details.

include/linux/blkdev.h

···
 	};
 
 	struct gendisk *rq_disk;
-	struct hd_struct *part;
+	struct block_device *part;
 #ifdef CONFIG_BLK_RQ_ALLOC_TIME
 	/* Time that the first bio started allocating this request. */
 	u64 alloc_time_ns;
···
 		return -1;
 	if (bdev_is_partition(bdev))
 		return queue_limit_alignment_offset(&q->limits,
-				bdev->bd_part->start_sect);
+				bdev->bd_start_sect);
 	return q->limits.alignment_offset;
 }
 
···
 
 	if (bdev_is_partition(bdev))
 		return queue_limit_discard_alignment(&q->limits,
-				bdev->bd_part->start_sect);
+				bdev->bd_start_sect);
 	return q->limits.discard_alignment;
 }
 
···
 	void (*unlock_native_capacity) (struct gendisk *);
 	int (*revalidate_disk) (struct gendisk *);
 	int (*getgeo)(struct block_device *, struct hd_geometry *);
+	int (*set_read_only)(struct block_device *bdev, bool ro);
 	/* this callback is with swap_lock and sometimes page table lock held */
 	void (*swap_slot_free_notify) (struct block_device *, unsigned long);
 	int (*report_zones)(struct gendisk *, sector_t sector,
···
 #define blkdev_compat_ptr_ioctl NULL
 #endif
 
-extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
-				 unsigned long);
 extern int bdev_read_page(struct block_device *, sector_t, struct page *);
 extern int bdev_write_page(struct block_device *, sector_t, struct page *,
 						struct writeback_control *);
···
 void disk_end_io_acct(struct gendisk *disk, unsigned int op,
 		unsigned long start_time);
 
-unsigned long part_start_io_acct(struct gendisk *disk, struct hd_struct **part,
-				 struct bio *bio);
-void part_end_io_acct(struct hd_struct *part, struct bio *bio,
+unsigned long part_start_io_acct(struct gendisk *disk,
+		struct block_device **part, struct bio *bio);
+void part_end_io_acct(struct block_device *part, struct bio *bio,
 		      unsigned long start_time);
 
 /**
···
 int set_blocksize(struct block_device *bdev, int size);
 
 const char *bdevname(struct block_device *bdev, char *buffer);
-struct block_device *lookup_bdev(const char *);
+int lookup_bdev(const char *pathname, dev_t *dev);
 
 void blkdev_show(struct seq_file *seqf, off_t offset);
 
···
 struct block_device *blkdev_get_by_path(const char *path, fmode_t mode,
 		void *holder);
 struct block_device *blkdev_get_by_dev(dev_t dev, fmode_t mode, void *holder);
-int bd_prepare_to_claim(struct block_device *bdev, struct block_device *whole,
-		void *holder);
-void bd_abort_claiming(struct block_device *bdev, struct block_device *whole,
-		void *holder);
+int bd_prepare_to_claim(struct block_device *bdev, void *holder);
+void bd_abort_claiming(struct block_device *bdev, void *holder);
 void blkdev_put(struct block_device *bdev, fmode_t mode);
 
+/* just for blk-cgroup, don't use elsewhere */
+struct block_device *blkdev_get_no_open(dev_t dev);
+void blkdev_put_no_open(struct block_device *bdev);
+
+struct block_device *bdev_alloc(struct gendisk *disk, u8 partno);
+void bdev_add(struct block_device *bdev, dev_t dev);
 struct block_device *I_BDEV(struct inode *inode);
-struct block_device *bdget_part(struct hd_struct *part);
 struct block_device *bdgrab(struct block_device *bdev);
 void bdput(struct block_device *);
 
···
 #endif
 int fsync_bdev(struct block_device *bdev);
 
-struct super_block *freeze_bdev(struct block_device *bdev);
-int thaw_bdev(struct block_device *bdev, struct super_block *sb);
+int freeze_bdev(struct block_device *bdev);
+int thaw_bdev(struct block_device *bdev);
 
 #endif /* _LINUX_BLKDEV_H */

include/linux/blktrace_api.h

···
 	return ret;
 }
 
-extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
-				void *data, size_t len);
+extern void blk_add_driver_data(struct request *rq, void *data, size_t len);
 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 			   struct block_device *bdev,
 			   char __user *arg);
···
 #else /* !CONFIG_BLK_DEV_IO_TRACE */
 # define blk_trace_ioctl(bdev, cmd, arg)		(-ENOTTY)
 # define blk_trace_shutdown(q)				do { } while (0)
-# define blk_add_driver_data(q, rq, data, len)		do {} while (0)
+# define blk_add_driver_data(rq, data, len)		do {} while (0)
 # define blk_trace_setup(q, name, dev, bdev, arg)	(-ENOTTY)
 # define blk_trace_startstop(q, start)			(-ENOTTY)
 # define blk_trace_remove(q)				(-ENOTTY)

include/linux/bvec.h

···
 	return true;
 }
 
-static inline void bvec_iter_skip_zero_bvec(struct bvec_iter *iter)
+/*
+ * A simpler version of bvec_iter_advance(), @bytes should not span
+ * across multiple bvec entries, i.e. bytes <= bv[i->bi_idx].bv_len
+ */
+static inline void bvec_iter_advance_single(const struct bio_vec *bv,
+				struct bvec_iter *iter, unsigned int bytes)
 {
-	iter->bi_bvec_done = 0;
-	iter->bi_idx++;
+	unsigned int done = iter->bi_bvec_done + bytes;
+
+	if (done == bv[iter->bi_idx].bv_len) {
+		done = 0;
+		iter->bi_idx++;
+	}
+	iter->bi_bvec_done = done;
+	iter->bi_size -= bytes;
 }
 
 #define for_each_bvec(bvl, bio_vec, iter, start)			\
 	for (iter = (start);						\
 	     (iter).bi_size &&						\
 		((bvl = bvec_iter_bvec((bio_vec), (iter))), 1);	\
-	     (bvl).bv_len ? (void)bvec_iter_advance((bio_vec), &(iter),	\
-		     (bvl).bv_len) : bvec_iter_skip_zero_bvec(&(iter)))
+	     bvec_iter_advance_single((bio_vec), &(iter), (bvl).bv_len))
 
 /* for iterating one bio from start to end */
 #define BVEC_ITER_ALL_INIT (struct bvec_iter)				\

include/linux/fs.h

···
 	struct list_head	i_devices;
 	union {
 		struct pipe_inode_info	*i_pipe;
-		struct block_device	*i_bdev;
 		struct cdev		*i_cdev;
 		char			*i_link;
 		unsigned		i_dir_seq;
···
 
 struct sb_writers {
 	int				frozen;		/* Is sb frozen? */
-	wait_queue_head_t		wait_unfrozen;	/* for get_super_thawed() */
+	wait_queue_head_t		wait_unfrozen;	/* wait for thaw */
 	struct percpu_rw_semaphore	rw_sem[SB_FREEZE_LEVELS];
 };
 
···
 extern void put_filesystem(struct file_system_type *fs);
 extern struct file_system_type *get_fs_type(const char *name);
 extern struct super_block *get_super(struct block_device *);
-extern struct super_block *get_super_thawed(struct block_device *);
-extern struct super_block *get_super_exclusive_thawed(struct block_device *bdev);
 extern struct super_block *get_active_super(struct block_device *bdev);
 extern void drop_super(struct super_block *sb);
 extern void drop_super_exclusive(struct super_block *sb);

include/linux/genhd.h

···
 #include <linux/blk_types.h>
 #include <asm/local.h>
 
-#define dev_to_disk(device)	container_of((device), struct gendisk, part0.__dev)
-#define dev_to_part(device)	container_of((device), struct hd_struct, __dev)
-#define disk_to_dev(disk)	(&(disk)->part0.__dev)
-#define part_to_dev(part)	(&((part)->__dev))
-
 extern const struct device_type disk_type;
 extern struct device_type part_type;
 extern struct class block_class;
···
 struct partition_meta_info {
 	char uuid[PARTITION_META_INFO_UUIDLTH];
 	u8 volname[PARTITION_META_INFO_VOLNAMELTH];
-};
-
-struct hd_struct {
-	sector_t start_sect;
-	/*
-	 * nr_sects is protected by sequence counter. One might extend a
-	 * partition while IO is happening to it and update of nr_sects
-	 * 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
-	unsigned long stamp;
-	struct disk_stats __percpu *dkstats;
-	struct percpu_ref ref;
-
-	struct device __dev;
-	struct kobject *holder_dir;
-	int policy, partno;
-	struct partition_meta_info *info;
-#ifdef CONFIG_FAIL_MAKE_REQUEST
-	int make_it_fail;
-#endif
-	struct rcu_work rcu_work;
 };
 
 /**
···
 struct disk_part_tbl {
 	struct rcu_head rcu_head;
 	int len;
-	struct hd_struct __rcu *last_lookup;
-	struct hd_struct __rcu *part[];
+	struct block_device __rcu *last_lookup;
+	struct block_device __rcu *part[];
 };
 
 struct disk_events;
···
 	 * helpers.
 	 */
 	struct disk_part_tbl __rcu *part_tbl;
-	struct hd_struct part0;
+	struct block_device *part0;
 
 	const struct block_device_operations *fops;
 	struct request_queue *queue;
···
 	int flags;
 	unsigned long state;
 #define GD_NEED_PART_SCAN		0
-	struct rw_semaphore lookup_sem;
 	struct kobject *slave_dir;
 
 	struct timer_rand_state *random;
···
 	struct lockdep_map lockdep_map;
 };
 
+/*
+ * The gendisk is refcounted by the part0 block_device, and the bd_device
+ * therein is also used for device model presentation in sysfs.
+ */
+#define dev_to_disk(device) \
+	(dev_to_bdev(device)->bd_disk)
+#define disk_to_dev(disk) \
+	(&((disk)->part0->bd_device))
+
 #if IS_REACHABLE(CONFIG_CDROM)
 #define disk_to_cdi(disk)	((disk)->cdi)
 #else
 #define disk_to_cdi(disk)	NULL
 #endif
-
-static inline struct gendisk *part_to_disk(struct hd_struct *part)
-{
-	if (likely(part)) {
-		if (part->partno)
-			return dev_to_disk(part_to_dev(part)->parent);
-		else
-			return dev_to_disk(part_to_dev(part));
-	}
-	return NULL;
-}
 
 static inline int disk_max_parts(struct gendisk *disk)
 {
···
 	return MKDEV(disk->major, disk->first_minor);
 }
 
-static inline dev_t part_devt(struct hd_struct *part)
-{
-	return part_to_dev(part)->devt;
-}
-
-extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
-extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
-
-static inline void disk_put_part(struct hd_struct *part)
-{
-	if (likely(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.
  */
···
 
 struct disk_part_iter {
 	struct gendisk		*disk;
-	struct hd_struct	*part;
+	struct block_device	*part;
 	int			idx;
 	unsigned int		flags;
 };
 
 extern void disk_part_iter_init(struct disk_part_iter *piter,
 				 struct gendisk *disk, unsigned int flags);
-extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
+struct block_device *disk_part_iter_next(struct disk_part_iter *piter);
 extern void disk_part_iter_exit(struct disk_part_iter *piter);
 extern bool disk_has_partitions(struct gendisk *disk);
 
···
 }
 
 extern void del_gendisk(struct gendisk *gp);
-extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 
-extern void set_device_ro(struct block_device *bdev, int flag);
 extern void set_disk_ro(struct gendisk *disk, int flag);
 
 static inline int get_disk_ro(struct gendisk *disk)
 {
-	return disk->part0.policy;
+	return disk->part0->bd_read_only;
 }
 
 extern void disk_block_events(struct gendisk *disk);
 extern void disk_unblock_events(struct gendisk *disk);
 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
-bool set_capacity_revalidate_and_notify(struct gendisk *disk, sector_t size,
-		bool update_bdev);
+bool set_capacity_and_notify(struct gendisk *disk, sector_t size);
 
 /* drivers/char/random.c */
 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
···
 
 static inline sector_t get_start_sect(struct block_device *bdev)
 {
-	return bdev->bd_part->start_sect;
+	return bdev->bd_start_sect;
 }
+
+static inline sector_t bdev_nr_sectors(struct block_device *bdev)
+{
+	return i_size_read(bdev->bd_inode) >> 9;
+}
+
 static inline sector_t get_capacity(struct gendisk *disk)
 {
-	return disk->part0.nr_sects;
-}
-static inline void set_capacity(struct gendisk *disk, sector_t size)
-{
-	disk->part0.nr_sects = size;
+	return bdev_nr_sectors(disk->part0);
 }
 
 int bdev_disk_changed(struct block_device *bdev, bool invalidate);
···
 int blk_drop_partitions(struct block_device *bdev);
 
 extern struct gendisk *__alloc_disk_node(int minors, int node_id);
-extern struct kobject *get_disk_and_module(struct gendisk *disk);
 extern void put_disk(struct gendisk *disk);
-extern void put_disk_and_module(struct gendisk *disk);
-extern void blk_register_region(dev_t devt, unsigned long range,
-			struct module *module,
-			struct kobject *(*probe)(dev_t, int *, void *),
-			int (*lock)(dev_t, void *),
-			void *data);
-extern void blk_unregister_region(dev_t devt, unsigned long range);
 
 #define alloc_disk_node(minors, node_id)				\
 ({									\
···
 
 #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
 
-int register_blkdev(unsigned int major, const char *name);
+int __register_blkdev(unsigned int major, const char *name,
+		void (*probe)(dev_t devt));
+#define register_blkdev(major, name) \
+	__register_blkdev(major, name, NULL)
 void unregister_blkdev(unsigned int major, const char *name);
 
-void revalidate_disk_size(struct gendisk *disk, bool verbose);
 bool bdev_check_media_change(struct block_device *bdev);
 int __invalidate_device(struct block_device *bdev, bool kill_dirty);
-void bd_set_nr_sectors(struct block_device *bdev, sector_t sectors);
+void set_capacity(struct gendisk *disk, sector_t size);
 
 /* for drivers/char/raw.c: */
 int blkdev_ioctl(struct block_device *, fmode_t, unsigned, unsigned long);
···
 }
 #endif /* CONFIG_SYSFS */
 
+extern struct rw_semaphore bdev_lookup_sem;
+
+dev_t blk_lookup_devt(const char *name, int partno);
+void blk_request_module(dev_t devt);
 #ifdef CONFIG_BLOCK
 void printk_all_partitions(void);
-dev_t blk_lookup_devt(const char *name, int partno);
 #else /* CONFIG_BLOCK */
 static inline void printk_all_partitions(void)
 {
-}
-static inline dev_t blk_lookup_devt(const char *name, int partno)
-{
-	dev_t devt = MKDEV(0, 0);
-	return devt;
 }
 #endif /* CONFIG_BLOCK */
 

include/linux/ide.h

···
 static inline void ide_acpi_set_state(ide_hwif_t *hwif, int on) {}
 #endif
 
-void ide_register_region(struct gendisk *);
-void ide_unregister_region(struct gendisk *);
-
 void ide_check_nien_quirk_list(ide_drive_t *);
 void ide_undecoded_slave(ide_drive_t *);
 

include/linux/part_stat.h

···
 #define part_stat_unlock()	preempt_enable()
 
 #define part_stat_get_cpu(part, field, cpu)				\
-	(per_cpu_ptr((part)->dkstats, (cpu))->field)
+	(per_cpu_ptr((part)->bd_stats, (cpu))->field)
 
 #define part_stat_get(part, field)					\
 	part_stat_get_cpu(part, field, smp_processor_id())
 
 #define part_stat_read(part, field)					\
 ({									\
-	typeof((part)->dkstats->field) res = 0;				\
+	typeof((part)->bd_stats->field) res = 0;			\
 	unsigned int _cpu;						\
 	for_each_possible_cpu(_cpu)					\
-		res += per_cpu_ptr((part)->dkstats, _cpu)->field;	\
+		res += per_cpu_ptr((part)->bd_stats, _cpu)->field; \
 	res;								\
 })
 
-static inline void part_stat_set_all(struct hd_struct *part, int value)
+static inline void part_stat_set_all(struct block_device *part, int value)
 {
 	int i;
 
 	for_each_possible_cpu(i)
-		memset(per_cpu_ptr(part->dkstats, i), value,
+		memset(per_cpu_ptr(part->bd_stats, i), value,
 				sizeof(struct disk_stats));
 }
 
···
 	 part_stat_read(part, field[STAT_DISCARD]))
 
 #define __part_stat_add(part, field, addnd)				\
-	__this_cpu_add((part)->dkstats->field, addnd)
+	__this_cpu_add((part)->bd_stats->field, addnd)
 
 #define part_stat_add(part, field, addnd)	do {			\
 	__part_stat_add((part), field, addnd);				\
-	if ((part)->partno)						\
-		__part_stat_add(&part_to_disk((part))->part0,		\
-				field, addnd);				\
+	if ((part)->bd_partno)						\
+		__part_stat_add(bdev_whole(part), field, addnd);	\
 } while (0)
 
-#define part_stat_dec(gendiskp, field)					\
-	part_stat_add(gendiskp, field, -1)
-#define part_stat_inc(gendiskp, field)					\
-	part_stat_add(gendiskp, field, 1)
-#define part_stat_sub(gendiskp, field, subnd)				\
-	part_stat_add(gendiskp, field, -subnd)
+#define part_stat_dec(part, field)					\
+	part_stat_add(part, field, -1)
+#define part_stat_inc(part, field)					\
+	part_stat_add(part, field, 1)
+#define part_stat_sub(part, field, subnd)				\
+	part_stat_add(part, field, -subnd)
 
-#define part_stat_local_dec(gendiskp, field)				\
-	local_dec(&(part_stat_get(gendiskp, field)))
-#define part_stat_local_inc(gendiskp, field)				\
-	local_inc(&(part_stat_get(gendiskp, field)))
-#define part_stat_local_read(gendiskp, field)				\
-	local_read(&(part_stat_get(gendiskp, field)))
-#define part_stat_local_read_cpu(gendiskp, field, cpu)			\
-	local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
+#define part_stat_local_dec(part, field)				\
+	local_dec(&(part_stat_get(part, field)))
+#define part_stat_local_inc(part, field)				\
+	local_inc(&(part_stat_get(part, field)))
+#define part_stat_local_read(part, field)				\
+	local_read(&(part_stat_get(part, field)))
+#define part_stat_local_read_cpu(part, field, cpu)			\
+	local_read(&(part_stat_get_cpu(part, field, cpu)))
 
 #endif /* _LINUX_PART_STAT_H */

include/linux/sbitmap.h

···
 	 * @cleared: word holding cleared bits
 	 */
 	unsigned long cleared ____cacheline_aligned_in_smp;
-
-	/**
-	 * @swap_lock: Held while swapping word <-> cleared
-	 */
-	spinlock_t swap_lock;
 } ____cacheline_aligned_in_smp;
 
 /**

include/trace/events/block.h

···
 
 /**
  * block_rq_requeue - place block IO request back on a queue
- * @q: queue holding operation
  * @rq: block IO operation request
  *
  * The block operation request @rq is being placed back into queue
···
  */
 TRACE_EVENT(block_rq_requeue,
 
-	TP_PROTO(struct request_queue *q, struct request *rq),
+	TP_PROTO(struct request *rq),
 
-	TP_ARGS(q, rq),
+	TP_ARGS(rq),
 
 	TP_STRUCT__entry(
 		__field(  dev_t,	dev			)
···
 
 DECLARE_EVENT_CLASS(block_rq,
 
-	TP_PROTO(struct request_queue *q, struct request *rq),
+	TP_PROTO(struct request *rq),
 
-	TP_ARGS(q, rq),
+	TP_ARGS(rq),
 
 	TP_STRUCT__entry(
 		__field(  dev_t,	dev			)
···
 
 /**
  * block_rq_insert - insert block operation request into queue
- * @q: target queue
  * @rq: block IO operation request
  *
  * Called immediately before block operation request @rq is inserted
···
  */
 DEFINE_EVENT(block_rq, block_rq_insert,
 
-	TP_PROTO(struct request_queue *q, struct request *rq),
+	TP_PROTO(struct request *rq),
 
-	TP_ARGS(q, rq)
+	TP_ARGS(rq)
 );
 
 /**
  * block_rq_issue - issue pending block IO request operation to device driver
- * @q: queue holding operation
  * @rq: block IO operation operation request
  *
  * Called when block operation request @rq from queue @q is sent to a
···
  */
 DEFINE_EVENT(block_rq, block_rq_issue,
 
-	TP_PROTO(struct request_queue *q, struct request *rq),
+	TP_PROTO(struct request *rq),
 
-	TP_ARGS(q, rq)
+	TP_ARGS(rq)
 );
 
 /**
  * block_rq_merge - merge request with another one in the elevator
- * @q: queue holding operation
  * @rq: block IO operation operation request
  *
  * Called when block operation request @rq from queue @q is merged to another
···
  */
 DEFINE_EVENT(block_rq, block_rq_merge,
 
-	TP_PROTO(struct request_queue *q, struct request *rq),
+	TP_PROTO(struct request *rq),
 
-	TP_ARGS(q, rq)
-);
-
-/**
- * block_bio_bounce - used bounce buffer when processing block operation
- * @q: queue holding the block operation
- * @bio: block operation
- *
- * A bounce buffer was used to handle the block operation @bio in @q.
- * This occurs when hardware limitations prevent a direct transfer of
- * data between the @bio data memory area and the IO device.  Use of a
- * bounce buffer requires extra copying of data and decreases
- * performance.
- */
-TRACE_EVENT(block_bio_bounce,
-
-	TP_PROTO(struct request_queue *q, struct bio *bio),
-
-	TP_ARGS(q, bio),
-
-	TP_STRUCT__entry(
-		__field( dev_t,		dev			)
-		__field( sector_t,	sector			)
-		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
-		__array( char,		comm,	TASK_COMM_LEN	)
-	),
-
-	TP_fast_assign(
-		__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);
-		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
-	),
-
-	TP_printk("%d,%d %s %llu + %u [%s]",
-		  MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
-		  (unsigned long long)__entry->sector,
-		  __entry->nr_sector, __entry->comm)
+	TP_ARGS(rq)
 );
 
 /**
···
 		  __entry->nr_sector, __entry->error)
 );
 
-DECLARE_EVENT_CLASS(block_bio_merge,
+DECLARE_EVENT_CLASS(block_bio,
 
-	TP_PROTO(struct request_queue *q, struct request *rq, struct bio *bio),
+	TP_PROTO(struct bio *bio),
 
-	TP_ARGS(q, rq, bio),
+	TP_ARGS(bio),
 
 	TP_STRUCT__entry(
 		__field( dev_t,		dev			)
···
 		  MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
 		  (unsigned long long)__entry->sector,
 		  __entry->nr_sector, __entry->comm)
+);
+
+/**
+ * block_bio_bounce - used bounce buffer when processing block operation
+ * @bio: block operation
+ *
+ * A bounce buffer was used to handle the block operation @bio in @q.
+ * This occurs when hardware limitations prevent a direct transfer of
+ * data between the @bio data memory area and the IO device.  Use of a
+ * bounce buffer requires extra copying of data and decreases
+ * performance.
+ */
+DEFINE_EVENT(block_bio, block_bio_bounce,
+	TP_PROTO(struct bio *bio),
+	TP_ARGS(bio)
 );
 
 /**
  * block_bio_backmerge - merging block operation to the end of an existing operation
- * @q: queue holding operation
- * @rq: request bio is being merged into
  * @bio: new block operation to merge
  *
- * Merging block request @bio to the end of an existing block request
- * in queue @q.
+ * Merging block request @bio to the end of an existing block request.
  */
-DEFINE_EVENT(block_bio_merge, block_bio_backmerge,
-
-	TP_PROTO(struct request_queue *q, struct request *rq, struct bio *bio),
-
-	TP_ARGS(q, rq, bio)
+DEFINE_EVENT(block_bio, block_bio_backmerge,
+	TP_PROTO(struct bio *bio),
+	TP_ARGS(bio)
 );
 
 /**
  * block_bio_frontmerge - merging block operation to the beginning of an existing operation
- * @q: queue holding operation
- * @rq: request bio is being merged into
  * @bio: new block operation to merge
  *
- * Merging block IO operation @bio to the beginning of an existing block
- * operation in queue @q.
+ * Merging block IO operation @bio to the beginning of an existing block request.
  */
-DEFINE_EVENT(block_bio_merge, block_bio_frontmerge,
-
-	TP_PROTO(struct request_queue *q, struct request *rq, struct bio *bio),
-
-	TP_ARGS(q, rq, bio)
+DEFINE_EVENT(block_bio, block_bio_frontmerge,
+	TP_PROTO(struct bio *bio),
+	TP_ARGS(bio)
 );
 
 /**
  * block_bio_queue - putting new block IO operation in queue
- * @q: queue holding operation
  * @bio: new block operation
  *
  * About to place the block IO operation @bio into queue @q.
  */
-TRACE_EVENT(block_bio_queue,
-
-	TP_PROTO(struct request_queue *q, struct bio *bio),
-
-	TP_ARGS(q, bio),
-
-	TP_STRUCT__entry(
-		__field( dev_t,		dev			)
-		__field( sector_t,	sector			)
-		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
-		__array( char,		comm,	TASK_COMM_LEN	)
-	),
-
-	TP_fast_assign(
-		__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);
-		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
-	),
-
-	TP_printk("%d,%d %s %llu + %u [%s]",
-		  MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
-		  (unsigned long long)__entry->sector,
-		  __entry->nr_sector, __entry->comm)
-);
-
-DECLARE_EVENT_CLASS(block_get_rq,
-
-	TP_PROTO(struct request_queue *q, struct bio *bio, int rw),
-
-	TP_ARGS(q, bio, rw),
-
-	TP_STRUCT__entry(
-		__field( dev_t,		dev			)
-		__field( sector_t,	sector			)
-		__field( unsigned int,	nr_sector		)
-		__array( char,		rwbs,	RWBS_LEN	)
-		__array( char,		comm,	TASK_COMM_LEN	)
-        ),
-
-	TP_fast_assign(
-		__entry->dev		= bio ? bio_dev(bio) : 0;
-		__entry->sector		= bio ? bio->bi_iter.bi_sector : 0;
-		__entry->nr_sector	= bio ? bio_sectors(bio) : 0;
-		blk_fill_rwbs(__entry->rwbs,
-			      bio ? bio->bi_opf : 0, __entry->nr_sector);
-		memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
-        ),
-
-	TP_printk("%d,%d %s %llu + %u [%s]",
-		  MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
-		  (unsigned long long)__entry->sector,
-		  __entry->nr_sector, __entry->comm)
+DEFINE_EVENT(block_bio, block_bio_queue,
+	TP_PROTO(struct bio *bio),
+	TP_ARGS(bio)
 );
 
 /**
  * block_getrq - get a free request entry in queue for block IO operations
- * @q: queue for operations
  * @bio: pending block IO operation (can be %NULL)
- * @rw: low bit indicates a read (%0) or a write (%1)
  *
- * A request struct for queue @q has been allocated to handle the
- * block IO operation @bio.
+ * A request struct has been allocated to handle the block IO operation @bio.
  */
-DEFINE_EVENT(block_get_rq, block_getrq,
-
-	TP_PROTO(struct request_queue *q, struct bio *bio, int rw),
-
-	TP_ARGS(q, bio, rw)
-);
-
-/**
- * block_sleeprq - waiting to get a free request entry in queue for block IO operation
- * @q: queue for operation
- * @bio: pending block IO operation (can be %NULL)
- * @rw: low bit indicates a read (%0) or a write (%1)
- *
- * In the case where a request struct cannot be provided for queue @q
- * the process needs to wait for an request struct to become
- * available.  This tracepoint event is generated each time the
- * process goes to sleep waiting for request struct become available.
- */
-DEFINE_EVENT(block_get_rq, block_sleeprq,
-
-	TP_PROTO(struct request_queue *q, struct bio *bio, int rw),
-
-	TP_ARGS(q, bio, rw)
+DEFINE_EVENT(block_bio, block_getrq,
+	TP_PROTO(struct bio *bio),
+	TP_ARGS(bio)
 );
 
 /**
···
 
 /**
  * block_split - split a single bio struct into two bio structs
- * @q: queue containing the bio
  * @bio: block operation being split
  * @new_sector: The starting sector for the new bio
  *
- * The bio request @bio in request queue @q needs to be split into two
- * bio requests. The newly created @bio request starts at
- * @new_sector. This split may be required due to hardware limitation
- * such as operation crossing device boundaries in a RAID system.
+ * The bio request @bio needs to be split into two bio requests.  The newly
+ * created @bio request starts at @new_sector. This split may be required due to
+ * hardware limitations such as operation crossing device boundaries in a RAID
+ * system.
  */
 TRACE_EVENT(block_split,
 
-	TP_PROTO(struct request_queue *q, struct bio *bio,
-		 unsigned int new_sector),
+	TP_PROTO(struct bio *bio, unsigned int new_sector),
 
-	TP_ARGS(q, bio, new_sector),
+	TP_ARGS(bio, new_sector),
 
 	TP_STRUCT__entry(
 		__field( dev_t,		dev				)
···
 
 /**
  * block_bio_remap - map request for a logical device to the raw device
- * @q: queue holding the operation
  * @bio: revised operation
- * @dev: device for the operation
+ * @dev: original device for the operation
  * @from: original sector for the operation
  *
  * An operation for a logical device has been mapped to the
···
  */
 TRACE_EVENT(block_bio_remap,
 
-	TP_PROTO(struct request_queue *q, struct bio *bio, dev_t dev,
-		 sector_t from),
+	TP_PROTO(struct bio *bio, dev_t dev, sector_t from),
 
-	TP_ARGS(q, bio, dev, from),
+	TP_ARGS(bio, dev, from),
 
 	TP_STRUCT__entry(
 		__field( dev_t,		dev		)
···
 
 /**
  * block_rq_remap - map request for a block operation request
- * @q: queue holding the operation
  * @rq: block IO operation request
  * @dev: device for the operation
  * @from: original sector for the operation
···
  */
 TRACE_EVENT(block_rq_remap,
 
-	TP_PROTO(struct request_queue *q, struct request *rq, dev_t dev,
-		 sector_t from),
+	TP_PROTO(struct request *rq, dev_t dev, sector_t from),
 
-	TP_ARGS(q, rq, dev, from),
+	TP_ARGS(rq, dev, from),
 
 	TP_STRUCT__entry(
 		__field( dev_t,		dev		)

init/do_mounts.c

···
  */
 static int match_dev_by_uuid(struct device *dev, const void *data)
 {
+	struct block_device *bdev = dev_to_bdev(dev);
 	const struct uuidcmp *cmp = data;
-	struct hd_struct *part = dev_to_part(dev);
 
-	if (!part->info)
-		goto no_match;
-
-	if (strncasecmp(cmp->uuid, part->info->uuid, cmp->len))
-		goto no_match;
-
+	if (!bdev->bd_meta_info ||
+	    strncasecmp(cmp->uuid, bdev->bd_meta_info->uuid, cmp->len))
+		return 0;
 	return 1;
-no_match:
-	return 0;
 }
-
 
 /**
  * devt_from_partuuid - looks up the dev_t of a partition by its UUID
···
  */
 static dev_t devt_from_partuuid(const char *uuid_str)
 {
-	dev_t res = 0;
 	struct uuidcmp cmp;
 	struct device *dev = NULL;
-	struct gendisk *disk;
-	struct hd_struct *part;
+	dev_t devt = 0;
 	int offset = 0;
-	bool clear_root_wait = false;
 	char *slash;
 
 	cmp.uuid = uuid_str;
···
 	/* Check for optional partition number offset attributes. */
 	if (slash) {
 		char c = 0;
+
 		/* Explicitly fail on poor PARTUUID syntax. */
-		if (sscanf(slash + 1,
-			   "PARTNROFF=%d%c", &offset, &c) != 1) {
-			clear_root_wait = true;
-			goto done;
-		}
+		if (sscanf(slash + 1, "PARTNROFF=%d%c", &offset, &c) != 1)
+			goto clear_root_wait;
 		cmp.len = slash - uuid_str;
 	} else {
 		cmp.len = strlen(uuid_str);
 	}
 
-	if (!cmp.len) {
-		clear_root_wait = true;
-		goto done;
-	}
+	if (!cmp.len)
+		goto clear_root_wait;
 
-	dev = class_find_device(&block_class, NULL, &cmp,
-				&match_dev_by_uuid);
+	dev = class_find_device(&block_class, NULL, &cmp, &match_dev_by_uuid);
 	if (!dev)
-		goto done;
+		return 0;
 
-	res = dev->devt;
+	if (offset) {
+		/*
+		 * Attempt to find the requested partition by adding an offset
+		 * to the partition number found by UUID.
+		 */
+		struct block_device *part;
 
-	/* Attempt to find the partition by offset. */
-	if (!offset)
-		goto no_offset;
-
-	res = 0;
-	disk = part_to_disk(dev_to_part(dev));
-	part = disk_get_part(disk, dev_to_part(dev)->partno + offset);
-	if (part) {
-		res = part_devt(part);
-		put_device(part_to_dev(part));
+		part = bdget_disk(dev_to_disk(dev),
+				  dev_to_bdev(dev)->bd_partno + offset);
+		if (part) {
+			devt = part->bd_dev;
+			bdput(part);
+		}
+	} else {
+		devt = dev->devt;
 	}
 
-no_offset:
 	put_device(dev);
-done:
-	if (clear_root_wait) {
-		pr_err("VFS: PARTUUID= is invalid.\n"
-		       "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
-		if (root_wait)
-			pr_err("Disabling rootwait; root= is invalid.\n");
-		root_wait = 0;
-	}
-	return res;
+	return devt;
+
+clear_root_wait:
+	pr_err("VFS: PARTUUID= is invalid.\n"
+	       "Expected PARTUUID=<valid-uuid-id>[/PARTNROFF=%%d]\n");
+	if (root_wait)
+		pr_err("Disabling rootwait; root= is invalid.\n");
+	root_wait = 0;
+	return 0;
 }
 
 /**
···
  */
 static int match_dev_by_label(struct device *dev, const void *data)
 {
+	struct block_device *bdev = dev_to_bdev(dev);
 	const char *label = data;
-	struct hd_struct *part = dev_to_part(dev);
 
-	if (part->info && !strcmp(label, part->info->volname))
-		return 1;
-
-	return 0;
+	if (!bdev->bd_meta_info || strcmp(label, bdev->bd_meta_info->volname))
+		return 0;
+	return 1;
 }
-#endif
+
+static dev_t devt_from_partlabel(const char *label)
+{
+	struct device *dev;
+	dev_t devt = 0;
+
+	dev = class_find_device(&block_class, NULL, label, &match_dev_by_label);
+	if (dev) {
+		devt = dev->devt;
+		put_device(dev);
+	}
+
+	return devt;
+}
+
+static dev_t devt_from_devname(const char *name)
+{
+	dev_t devt = 0;
+	int part;
+	char s[32];
+	char *p;
+
+	if (strlen(name) > 31)
+		return 0;
+	strcpy(s, name);
+	for (p = s; *p; p++) {
+		if (*p == '/')
+			*p = '!';
+	}
+
+	devt = blk_lookup_devt(s, 0);
+	if (devt)
+		return devt;
+
+	/*
+	 * Try non-existent, but valid partition, which may only exist after
+	 * opening the device, like partitioned md devices.
+	 */
+	while (p > s && isdigit(p[-1]))
+		p--;
+	if (p == s || !*p || *p == '0')
+		return 0;
+
+	/* try disk name without <part number> */
+	part = simple_strtoul(p, NULL, 10);
+	*p = '\0';
+	devt = blk_lookup_devt(s, part);
+	if (devt)
+		return devt;
+
+	/* try disk name without p<part number> */
+	if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
+		return 0;
+	p[-1] = '\0';
+	return blk_lookup_devt(s, part);
+}
+#endif /* CONFIG_BLOCK */
+
+static dev_t devt_from_devnum(const char *name)
+{
+	unsigned maj, min, offset;
+	dev_t devt = 0;
+	char *p, dummy;
+
+	if (sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2 ||
+	    sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3) {
+		devt = MKDEV(maj, min);
+		if (maj != MAJOR(devt) || min != MINOR(devt))
+			return 0;
+	} else {
+		devt = new_decode_dev(simple_strtoul(name, &p, 16));
+		if (*p)
+			return 0;
+	}
+
+	return devt;
+}
 
 /*
  *	Convert a name into device number.  We accept the following variants:
···
  *	name contains slashes, the device name has them replaced with
  *	bangs.
  */
-
 dev_t name_to_dev_t(const char *name)
 {
-	char s[32];
-	char *p;
-	dev_t res = 0;
-	int part;
-
+	if (strcmp(name, "/dev/nfs") == 0)
+		return Root_NFS;
+	if (strcmp(name, "/dev/cifs") == 0)
+		return Root_CIFS;
+	if (strcmp(name, "/dev/ram") == 0)
+		return Root_RAM0;
 #ifdef CONFIG_BLOCK
-	if (strncmp(name, "PARTUUID=", 9) == 0) {
-		name += 9;
-		res = devt_from_partuuid(name);
-		if (!res)
-			goto fail;
-		goto done;
-	} else if (strncmp(name, "PARTLABEL=", 10) == 0) {
-		struct device *dev;
-
-		dev = class_find_device(&block_class, NULL, name + 10,
-					&match_dev_by_label);
-		if (!dev)
-			goto fail;
-
-		res = dev->devt;
-		put_device(dev);
-		goto done;
-	}
+	if (strncmp(name, "PARTUUID=", 9) == 0)
+		return devt_from_partuuid(name + 9);
+	if (strncmp(name, "PARTLABEL=", 10) == 0)
+		return devt_from_partlabel(name + 10);
+	if (strncmp(name, "/dev/", 5) == 0)
+		return devt_from_devname(name + 5);
 #endif
-
-	if (strncmp(name, "/dev/", 5) != 0) {
-		unsigned maj, min, offset;
-		char dummy;
-
-		if ((sscanf(name, "%u:%u%c", &maj, &min, &dummy) == 2) ||
-		    (sscanf(name, "%u:%u:%u:%c", &maj, &min, &offset, &dummy) == 3)) {
-			res = MKDEV(maj, min);
-			if (maj != MAJOR(res) || min != MINOR(res))
-				goto fail;
-		} else {
-			res = new_decode_dev(simple_strtoul(name, &p, 16));
-			if (*p)
-				goto fail;
-		}
-		goto done;
-	}
-
-	name += 5;
-	res = Root_NFS;
-	if (strcmp(name, "nfs") == 0)
-		goto done;
-	res = Root_CIFS;
-	if (strcmp(name, "cifs") == 0)
-		goto done;
-	res = Root_RAM0;
-	if (strcmp(name, "ram") == 0)
-		goto done;
-
-	if (strlen(name) > 31)
-		goto fail;
-	strcpy(s, name);
-	for (p = s; *p; p++)
-		if (*p == '/')
-			*p = '!';
-	res = blk_lookup_devt(s, 0);
-	if (res)
-		goto done;
-
-	/*
-	 * try non-existent, but valid partition, which may only exist
-	 * after revalidating the disk, like partitioned md devices
-	 */
-	while (p > s && isdigit(p[-1]))
-		p--;
-	if (p == s || !*p || *p == '0')
-		goto fail;
-
-	/* try disk name without <part number> */
-	part = simple_strtoul(p, NULL, 10);
-	*p = '\0';
-	res = blk_lookup_devt(s, part);
-	if (res)
-		goto done;
-
-	/* try disk name without p<part number> */
-	if (p < s + 2 || !isdigit(p[-2]) || p[-1] != 'p')
-		goto fail;
-	p[-1] = '\0';
-	res = blk_lookup_devt(s, part);
-	if (res)
-		goto done;
-
-fail:
-	return 0;
-done:
-	return res;
+	return devt_from_devnum(name);
 }
 EXPORT_SYMBOL_GPL(name_to_dev_t);
 

kernel/trace/blktrace.c

···
 static void blk_trace_setup_lba(struct blk_trace *bt,
 				struct block_device *bdev)
 {
-	struct hd_struct *part = NULL;
-
-	if (bdev)
-		part = bdev->bd_part;
-
-	if (part) {
-		bt->start_lba = part->start_sect;
-		bt->end_lba = part->start_sect + part->nr_sects;
+	if (bdev) {
+		bt->start_lba = bdev->bd_start_sect;
+		bt->end_lba = bdev->bd_start_sect + bdev_nr_sectors(bdev);
 	} else {
 		bt->start_lba = 0;
 		bt->end_lba = -1ULL;
···
 #endif
 
 static u64
-blk_trace_request_get_cgid(struct request_queue *q, struct request *rq)
+blk_trace_request_get_cgid(struct request *rq)
 {
 	if (!rq->bio)
 		return 0;
 	/* Use the first bio */
-	return blk_trace_bio_get_cgid(q, rq->bio);
+	return blk_trace_bio_get_cgid(rq->q, rq->bio);
 }
 
 /*
···
 	rcu_read_unlock();
 }
 
-static void blk_add_trace_rq_insert(void *ignore,
-				    struct request_queue *q, struct request *rq)
+static void blk_add_trace_rq_insert(void *ignore, struct request *rq)
 {
 	blk_add_trace_rq(rq, 0, blk_rq_bytes(rq), BLK_TA_INSERT,
-			 blk_trace_request_get_cgid(q, rq));
+			 blk_trace_request_get_cgid(rq));
 }
 
-static void blk_add_trace_rq_issue(void *ignore,
-				   struct request_queue *q, struct request *rq)
+static void blk_add_trace_rq_issue(void *ignore, struct request *rq)
 {
 	blk_add_trace_rq(rq, 0, blk_rq_bytes(rq), BLK_TA_ISSUE,
-			 blk_trace_request_get_cgid(q, rq));
+			 blk_trace_request_get_cgid(rq));
 }
 
-static void blk_add_trace_rq_merge(void *ignore,
-				   struct request_queue *q, struct request *rq)
+static void blk_add_trace_rq_merge(void *ignore, struct request *rq)
 {
 	blk_add_trace_rq(rq, 0, blk_rq_bytes(rq), BLK_TA_BACKMERGE,
-			 blk_trace_request_get_cgid(q, rq));
+			 blk_trace_request_get_cgid(rq));
 }
 
-static void blk_add_trace_rq_requeue(void *ignore,
-				     struct request_queue *q,
-				     struct request *rq)
+static void blk_add_trace_rq_requeue(void *ignore, struct request *rq)
 {
 	blk_add_trace_rq(rq, 0, blk_rq_bytes(rq), BLK_TA_REQUEUE,
-			 blk_trace_request_get_cgid(q, rq));
+			 blk_trace_request_get_cgid(rq));
 }
 
 static void blk_add_trace_rq_complete(void *ignore, struct request *rq,
 			int error, unsigned int nr_bytes)
 {
 	blk_add_trace_rq(rq, error, nr_bytes, BLK_TA_COMPLETE,
-			 blk_trace_request_get_cgid(rq->q, rq));
+			 blk_trace_request_get_cgid(rq));
 }
 
 /**
···
 	rcu_read_unlock();
 }
 
-static void blk_add_trace_bio_bounce(void *ignore,
-				     struct request_queue *q, struct bio *bio)
+static void blk_add_trace_bio_bounce(void *ignore, struct bio *bio)
 {
-	blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0);
+	blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_BOUNCE, 0);
 }
 
 static void blk_add_trace_bio_complete(void *ignore,
···
 			  blk_status_to_errno(bio->bi_status));
 }
 
-static void blk_add_trace_bio_backmerge(void *ignore,
-					struct request_queue *q,
-					struct request *rq,
-					struct bio *bio)
+static void blk_add_trace_bio_backmerge(void *ignore, struct bio *bio)
 {
-	blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0);
+	blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_BACKMERGE, 0);
 }
 
-static void blk_add_trace_bio_frontmerge(void *ignore,
-					 struct request_queue *q,
-					 struct request *rq,
-					 struct bio *bio)
+static void blk_add_trace_bio_frontmerge(void *ignore, struct bio *bio)
 {
-	blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0);
+	blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_FRONTMERGE, 0);
 }
 
-static void blk_add_trace_bio_queue(void *ignore,
-				    struct request_queue *q, struct bio *bio)
+static void blk_add_trace_bio_queue(void *ignore, struct bio *bio)
 {
-	blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0);
+	blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_QUEUE, 0);
 }
 
-static void blk_add_trace_getrq(void *ignore,
-				struct request_queue *q,
-				struct bio *bio, int rw)
+static void blk_add_trace_getrq(void *ignore, struct bio *bio)
 {
-	if (bio)
-		blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0);
-	else {
-		struct blk_trace *bt;
-
-		rcu_read_lock();
-		bt = rcu_dereference(q->blk_trace);
-		if (bt)
-			__blk_add_trace(bt, 0, 0, rw, 0, BLK_TA_GETRQ, 0, 0,
-					NULL, 0);
-		rcu_read_unlock();
-	}
-}
-
-
-static void blk_add_trace_sleeprq(void *ignore,
-				  struct request_queue *q,
-				  struct bio *bio, int rw)
-{
-	if (bio)
-		blk_add_trace_bio(q, bio, BLK_TA_SLEEPRQ, 0);
-	else {
-		struct blk_trace *bt;
-
-		rcu_read_lock();
-		bt = rcu_dereference(q->blk_trace);
-		if (bt)
-			__blk_add_trace(bt, 0, 0, rw, 0, BLK_TA_SLEEPRQ,
-					0, 0, NULL, 0);
-		rcu_read_unlock();
-	}
+	blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_GETRQ, 0);
 }
 
 static void blk_add_trace_plug(void *ignore, struct request_queue *q)
···
 	rcu_read_unlock();
 }
 
-static void blk_add_trace_split(void *ignore,
-				struct request_queue *q, struct bio *bio,
-				unsigned int pdu)
+static void blk_add_trace_split(void *ignore, struct bio *bio, unsigned int pdu)
 {
+	struct request_queue *q = bio->bi_disk->queue;
 	struct blk_trace *bt;
 
 	rcu_read_lock();
···
 /**
  * blk_add_trace_bio_remap - Add a trace for a bio-remap operation
  * @ignore:	trace callback data parameter (not used)
- * @q:		queue the io is for
  * @bio:	the source bio
- * @dev:	target device
+ * @dev:	source device
  * @from:	source sector
  *
- * Description:
- *     Device mapper or raid target sometimes need to split a bio because
- *     it spans a stripe (or similar). Add a trace for that action.
- *
+ * Called after a bio is remapped to a different device and/or sector.
  **/
-static void blk_add_trace_bio_remap(void *ignore,
-				    struct request_queue *q, struct bio *bio,
-				    dev_t dev, sector_t from)
+static void blk_add_trace_bio_remap(void *ignore, struct bio *bio, dev_t dev,
+				    sector_t from)
 {
+	struct request_queue *q = bio->bi_disk->queue;
 	struct blk_trace *bt;
 	struct blk_io_trace_remap r;
 
···
 /**
  * blk_add_trace_rq_remap - Add a trace for a request-remap operation
  * @ignore:	trace callback data parameter (not used)
- * @q:		queue the io is for
  * @rq:		the source request
  * @dev:	target device
  * @from:	source sector
···
  *     Add a trace for that action.
  *
  **/
-static void blk_add_trace_rq_remap(void *ignore,
-				   struct request_queue *q,
-				   struct request *rq, dev_t dev,
+static void blk_add_trace_rq_remap(void *ignore, struct request *rq, dev_t dev,
 				   sector_t from)
 {
 	struct blk_trace *bt;
 	struct blk_io_trace_remap r;
 
 	rcu_read_lock();
-	bt = rcu_dereference(q->blk_trace);
+	bt = rcu_dereference(rq->q->blk_trace);
 	if (likely(!bt)) {
 		rcu_read_unlock();
 		return;
···
 
 	__blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq),
 			rq_data_dir(rq), 0, BLK_TA_REMAP, 0,
-			sizeof(r), &r, blk_trace_request_get_cgid(q, rq));
+			sizeof(r), &r, blk_trace_request_get_cgid(rq));
 	rcu_read_unlock();
 }
 
 /**
  * blk_add_driver_data - Add binary message with driver-specific data
- * @q:		queue the io is for
  * @rq:		io request
  * @data:	driver-specific data
  * @len:	length of driver-specific data
···
  *     Some drivers might want to write driver-specific data per request.
  *
  **/
-void blk_add_driver_data(struct request_queue *q,
-			 struct request *rq,
-			 void *data, size_t len)
+void blk_add_driver_data(struct request *rq, void *data, size_t len)
 {
 	struct blk_trace *bt;
 
 	rcu_read_lock();
-	bt = rcu_dereference(q->blk_trace);
+	bt = rcu_dereference(rq->q->blk_trace);
 	if (likely(!bt)) {
 		rcu_read_unlock();
 		return;
···
 
 	__blk_add_trace(bt, blk_rq_trace_sector(rq), blk_rq_bytes(rq), 0, 0,
 				BLK_TA_DRV_DATA, 0, len, data,
-				blk_trace_request_get_cgid(q, rq));
+				blk_trace_request_get_cgid(rq));
 	rcu_read_unlock();
 }
 EXPORT_SYMBOL_GPL(blk_add_driver_data);
···
 	WARN_ON(ret);
 	ret = register_trace_block_getrq(blk_add_trace_getrq, NULL);
 	WARN_ON(ret);
-	ret = register_trace_block_sleeprq(blk_add_trace_sleeprq, NULL);
-	WARN_ON(ret);
 	ret = register_trace_block_plug(blk_add_trace_plug, NULL);
 	WARN_ON(ret);
 	ret = register_trace_block_unplug(blk_add_trace_unplug, NULL);
···
 	unregister_trace_block_split(blk_add_trace_split, NULL);
 	unregister_trace_block_unplug(blk_add_trace_unplug, NULL);
 	unregister_trace_block_plug(blk_add_trace_plug, NULL);
-	unregister_trace_block_sleeprq(blk_add_trace_sleeprq, NULL);
 	unregister_trace_block_getrq(blk_add_trace_getrq, NULL);
 	unregister_trace_block_bio_queue(blk_add_trace_bio_queue, NULL);
 	unregister_trace_block_bio_frontmerge(blk_add_trace_bio_frontmerge, NULL);
···
 	return p - buf;
 }
 
-static struct request_queue *blk_trace_get_queue(struct block_device *bdev)
-{
-	if (bdev->bd_disk == NULL)
-		return NULL;
-
-	return bdev_get_queue(bdev);
-}
-
 static ssize_t sysfs_blk_trace_attr_show(struct device *dev,
 					 struct device_attribute *attr,
 					 char *buf)
 {
-	struct block_device *bdev = bdget_part(dev_to_part(dev));
-	struct request_queue *q;
+	struct block_device *bdev = dev_to_bdev(dev);
+	struct request_queue *q = bdev_get_queue(bdev);
 	struct blk_trace *bt;
 	ssize_t ret = -ENXIO;
-
-	if (bdev == NULL)
-		goto out;
-
-	q = blk_trace_get_queue(bdev);
-	if (q == NULL)
-		goto out_bdput;
 
 	mutex_lock(&q->debugfs_mutex);
 
···
 
 out_unlock_bdev:
 	mutex_unlock(&q->debugfs_mutex);
-out_bdput:
-	bdput(bdev);
-out:
 	return ret;
 }
 
···
 					  struct device_attribute *attr,
 					  const char *buf, size_t count)
 {
-	struct block_device *bdev;
-	struct request_queue *q;
+	struct block_device *bdev = dev_to_bdev(dev);
+	struct request_queue *q = bdev_get_queue(bdev);
 	struct blk_trace *bt;
 	u64 value;
 	ssize_t ret = -EINVAL;
···
 				goto out;
 			value = ret;
 		}
-	} else if (kstrtoull(buf, 0, &value))
-		goto out;
-
-	ret = -ENXIO;
-	bdev = bdget_part(dev_to_part(dev));
-	if (bdev == NULL)
-		goto out;
-
-	q = blk_trace_get_queue(bdev);
-	if (q == NULL)
-		goto out_bdput;
+	} else {
+		if (kstrtoull(buf, 0, &value))
+			goto out;
+	}
 
 	mutex_lock(&q->debugfs_mutex);
 
···
 
 out_unlock_bdev:
 	mutex_unlock(&q->debugfs_mutex);
-out_bdput:
-	bdput(bdev);
 out:
 	return ret ? ret : count;
 }

lib/sbitmap.c

···
 /*
  * See if we have deferred clears that we can batch move
  */
-static inline bool sbitmap_deferred_clear(struct sbitmap *sb, int index)
+static inline bool sbitmap_deferred_clear(struct sbitmap_word *map)
 {
-	unsigned long mask, val;
-	bool ret = false;
-	unsigned long flags;
+	unsigned long mask;
 
-	spin_lock_irqsave(&sb->map[index].swap_lock, flags);
-
-	if (!sb->map[index].cleared)
-		goto out_unlock;
+	if (!READ_ONCE(map->cleared))
+		return false;
 
 	/*
 	 * First get a stable cleared mask, setting the old mask to 0.
 	 */
-	mask = xchg(&sb->map[index].cleared, 0);
+	mask = xchg(&map->cleared, 0);
 
 	/*
 	 * Now clear the masked bits in our free word
 	 */
-	do {
-		val = sb->map[index].word;
-	} while (cmpxchg(&sb->map[index].word, val, val & ~mask) != val);
-
-	ret = true;
-out_unlock:
-	spin_unlock_irqrestore(&sb->map[index].swap_lock, flags);
-	return ret;
+	atomic_long_andnot(mask, (atomic_long_t *)&map->word);
+	BUILD_BUG_ON(sizeof(atomic_long_t) != sizeof(map->word));
+	return true;
 }
 
 int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift,
···
 	for (i = 0; i < sb->map_nr; i++) {
 		sb->map[i].depth = min(depth, bits_per_word);
 		depth -= sb->map[i].depth;
-		spin_lock_init(&sb->map[i].swap_lock);
 	}
 	return 0;
 }
···
 	unsigned int i;
 
 	for (i = 0; i < sb->map_nr; i++)
-		sbitmap_deferred_clear(sb, i);
+		sbitmap_deferred_clear(&sb->map[i]);
 
 	sb->depth = depth;
 	sb->map_nr = DIV_ROUND_UP(sb->depth, bits_per_word);
···
 static int __sbitmap_get_word(unsigned long *word, unsigned long depth,
 			      unsigned int hint, bool wrap)
 {
-	unsigned int orig_hint = hint;
 	int nr;
+
+	/* don't wrap if starting from 0 */
+	wrap = wrap && hint;
 
 	while (1) {
 		nr = find_next_zero_bit(word, depth, hint);
···
 			 * offset to 0 in a failure case, so start from 0 to
 			 * exhaust the map.
 			 */
-			if (orig_hint && hint && wrap) {
-				hint = orig_hint = 0;
+			if (hint && wrap) {
+				hint = 0;
 				continue;
 			}
 			return -1;
···
 static int sbitmap_find_bit_in_index(struct sbitmap *sb, int index,
 				     unsigned int alloc_hint, bool round_robin)
 {
+	struct sbitmap_word *map = &sb->map[index];
 	int nr;
 
 	do {
-		nr = __sbitmap_get_word(&sb->map[index].word,
-					sb->map[index].depth, alloc_hint,
+		nr = __sbitmap_get_word(&map->word, map->depth, alloc_hint,
 					!round_robin);
 		if (nr != -1)
 			break;
-		if (!sbitmap_deferred_clear(sb, index))
+		if (!sbitmap_deferred_clear(map))
 			break;
 	} while (1);
 
···
 			break;
 		}
 
-		if (sbitmap_deferred_clear(sb, index))
+		if (sbitmap_deferred_clear(&sb->map[index]))
 			goto again;
 
 		/* Jump to next index. */

mm/filemap.c

···
 
 vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf)
 {
+	struct address_space *mapping = vmf->vma->vm_file->f_mapping;
 	struct page *page = vmf->page;
-	struct inode *inode = file_inode(vmf->vma->vm_file);
 	vm_fault_t ret = VM_FAULT_LOCKED;
 
-	sb_start_pagefault(inode->i_sb);
+	sb_start_pagefault(mapping->host->i_sb);
 	file_update_time(vmf->vma->vm_file);
 	lock_page(page);
-	if (page->mapping != inode->i_mapping) {
+	if (page->mapping != mapping) {
 		unlock_page(page);
 		ret = VM_FAULT_NOPAGE;
 		goto out;
···
 	set_page_dirty(page);
 	wait_for_stable_page(page);
 out:
-	sb_end_pagefault(inode->i_sb);
+	sb_end_pagefault(mapping->host->i_sb);
 	return ret;
 }
 
···
 {
 	static DEFINE_RATELIMIT_STATE(_rs, 86400 * HZ, DEFAULT_RATELIMIT_BURST);
 	char pathname[128];
-	struct inode *inode = file_inode(filp);
 	char *path;
 
-	errseq_set(&inode->i_mapping->wb_err, -EIO);
+	errseq_set(&filp->f_mapping->wb_err, -EIO);
 	if (__ratelimit(&_rs)) {
 		path = file_path(filp, pathname, sizeof(pathname));
 		if (IS_ERR(path))
···
 
 	if (iocb->ki_flags & IOCB_NOWAIT) {
 		/* If there are pages to writeback, return */
-		if (filemap_range_has_page(inode->i_mapping, pos,
+		if (filemap_range_has_page(file->f_mapping, pos,
 					   pos + write_len - 1))
 			return -EAGAIN;
 	} else {