Merge tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux

Pull block updates from Jens Axboe:

 - NVMe pull request via Keith:
      - Various cleanups all around (Irvin, Chaitanya, Christophe)
      - Better struct packing (Christophe JAILLET)
      - Reduce controller error logs for optional commands (Keith)
      - Support for >=64KiB block sizes (Daniel Gomez)
      - Fabrics fixes and code organization (Max, Chaitanya, Daniel
        Wagner)

 - bcache updates via Coly:
      - Fix a race at init time (Mingzhe Zou)
      - Misc fixes and cleanups (Andrea, Thomas, Zheng, Ye)

 - use page pinning in the block layer for dio (David)

 - convert old block dio code to page pinning (David, Christoph)

 - cleanups for pktcdvd (Andy)

 - cleanups for rnbd (Guoqing)

 - use the unchecked __bio_add_page() for the initial single page
   additions (Johannes)

 - fix overflows in the Amiga partition handling code (Michael)

 - improve mq-deadline zoned device support (Bart)

 - keep passthrough requests out of the IO schedulers (Christoph, Ming)

 - improve support for flush requests, making them less special to deal
   with (Christoph)

 - add bdev holder ops and shutdown methods (Christoph)

 - fix the name_to_dev_t() situation and use cases (Christoph)

 - decouple the block open flags from fmode_t (Christoph)

 - ublk updates and cleanups, including adding user copy support (Ming)

 - BFQ sanity checking (Bart)

 - convert brd from radix to xarray (Pankaj)

 - constify various structures (Thomas, Ivan)

 - more fine grained persistent reservation ioctl capability checks
   (Jingbo)

 - misc fixes and cleanups (Arnd, Azeem, Demi, Ed, Hengqi, Hou, Jan,
   Jordy, Li, Min, Yu, Zhong, Waiman)

* tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux: (266 commits)
  scsi/sg: don't grab scsi host module reference
  ext4: Fix warning in blkdev_put()
  block: don't return -EINVAL for not found names in devt_from_devname
  cdrom: Fix spectre-v1 gadget
  block: Improve kernel-doc headers
  blk-mq: don't insert passthrough request into sw queue
  bsg: make bsg_class a static const structure
  ublk: make ublk_chr_class a static const structure
  aoe: make aoe_class a static const structure
  block/rnbd: make all 'class' structures const
  block: fix the exclusive open mask in disk_scan_partitions
  block: add overflow checks for Amiga partition support
  block: change all __u32 annotations to __be32 in affs_hardblocks.h
  block: fix signed int overflow in Amiga partition support
  block: add capacity validation in bdev_add_partition()
  block: fine-granular CAP_SYS_ADMIN for Persistent Reservation
  block: disallow Persistent Reservation on partitions
  reiserfs: fix blkdev_put() warning from release_journal_dev()
  block: fix wrong mode for blkdev_get_by_dev() from disk_scan_partitions()
  block: document the holder argument to blkdev_get_by_path
  ...

31 files changed, 922 insertions, 785 deletions

diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 4c8b2ba579ee..e460c9799d9f 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -1532,7 +1532,7 @@ static int fd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 	return 0;
 }
 
-static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
+static int fd_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
 		    unsigned int cmd, unsigned long param)
 {
 	struct amiga_floppy_struct *p = bdev->bd_disk->private_data;
@@ -1607,7 +1607,7 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
 	return 0;
 }
 
-static int fd_ioctl(struct block_device *bdev, fmode_t mode,
+static int fd_ioctl(struct block_device *bdev, blk_mode_t mode,
 			     unsigned int cmd, unsigned long param)
 {
 	int ret;
@@ -1654,10 +1654,10 @@ static void fd_probe(int dev)
  * /dev/PS0 etc), and disallows simultaneous access to the same
  * drive with different device numbers.
  */
-static int floppy_open(struct block_device *bdev, fmode_t mode)
+static int floppy_open(struct gendisk *disk, blk_mode_t mode)
 {
-	int drive = MINOR(bdev->bd_dev) & 3;
-	int system =  (MINOR(bdev->bd_dev) & 4) >> 2;
+	int drive = disk->first_minor & 3;
+	int system = (disk->first_minor & 4) >> 2;
 	int old_dev;
 	unsigned long flags;
 
@@ -1673,10 +1673,9 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 		mutex_unlock(&amiflop_mutex);
 		return -ENXIO;
 	}
-
-	if (mode & (FMODE_READ|FMODE_WRITE)) {
-		bdev_check_media_change(bdev);
-		if (mode & FMODE_WRITE) {
+	if (mode & (BLK_OPEN_READ | BLK_OPEN_WRITE)) {
+		disk_check_media_change(disk);
+		if (mode & BLK_OPEN_WRITE) {
 			int wrprot;
 
 			get_fdc(drive);
@@ -1691,7 +1690,6 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 			}
 		}
 	}
-
 	local_irq_save(flags);
 	fd_ref[drive]++;
 	fd_device[drive] = system;
@@ -1709,7 +1707,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
-static void floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk)
 {
 	struct amiga_floppy_struct *p = disk->private_data;
 	int drive = p - unit;
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 128722cf6c3c..cf6883756155 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -204,9 +204,9 @@ aoedisk_rm_debugfs(struct aoedev *d)
 }
 
 static int
-aoeblk_open(struct block_device *bdev, fmode_t mode)
+aoeblk_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct aoedev *d = bdev->bd_disk->private_data;
+	struct aoedev *d = disk->private_data;
 	ulong flags;
 
 	if (!virt_addr_valid(d)) {
@@ -232,7 +232,7 @@ aoeblk_open(struct block_device *bdev, fmode_t mode)
 }
 
 static void
-aoeblk_release(struct gendisk *disk, fmode_t mode)
+aoeblk_release(struct gendisk *disk)
 {
 	struct aoedev *d = disk->private_data;
 	ulong flags;
@@ -285,7 +285,7 @@ aoeblk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 }
 
 static int
-aoeblk_ioctl(struct block_device *bdev, fmode_t mode, uint cmd, ulong arg)
+aoeblk_ioctl(struct block_device *bdev, blk_mode_t mode, uint cmd, ulong arg)
 {
 	struct aoedev *d;
 
diff --git a/drivers/block/aoe/aoechr.c b/drivers/block/aoe/aoechr.c
index 4c666f72203f..a42c4bcc85ba 100644
--- a/drivers/block/aoe/aoechr.c
+++ b/drivers/block/aoe/aoechr.c
@@ -49,7 +49,7 @@ static int emsgs_head_idx, emsgs_tail_idx;
 static struct completion emsgs_comp;
 static spinlock_t emsgs_lock;
 static int nblocked_emsgs_readers;
-static struct class *aoe_class;
+
 static struct aoe_chardev chardevs[] = {
 	{ MINOR_ERR, "err" },
 	{ MINOR_DISCOVER, "discover" },
@@ -58,6 +58,16 @@ static struct aoe_chardev chardevs[] = {
 	{ MINOR_FLUSH, "flush" },
 };
 
+static char *aoe_devnode(const struct device *dev, umode_t *mode)
+{
+	return kasprintf(GFP_KERNEL, "etherd/%s", dev_name(dev));
+}
+
+static const struct class aoe_class = {
+	.name = "aoe",
+	.devnode = aoe_devnode,
+};
+
 static int
 discover(void)
 {
@@ -273,11 +283,6 @@ static const struct file_operations aoe_fops = {
 	.llseek = noop_llseek,
 };
 
-static char *aoe_devnode(const struct device *dev, umode_t *mode)
-{
-	return kasprintf(GFP_KERNEL, "etherd/%s", dev_name(dev));
-}
-
 int __init
 aoechr_init(void)
 {
@@ -290,15 +295,14 @@ aoechr_init(void)
 	}
 	init_completion(&emsgs_comp);
 	spin_lock_init(&emsgs_lock);
-	aoe_class = class_create("aoe");
-	if (IS_ERR(aoe_class)) {
+	n = class_register(&aoe_class);
+	if (n) {
 		unregister_chrdev(AOE_MAJOR, "aoechr");
-		return PTR_ERR(aoe_class);
+		return n;
 	}
-	aoe_class->devnode = aoe_devnode;
 
 	for (i = 0; i < ARRAY_SIZE(chardevs); ++i)
-		device_create(aoe_class, NULL,
+		device_create(&aoe_class, NULL,
 			      MKDEV(AOE_MAJOR, chardevs[i].minor), NULL,
 			      chardevs[i].name);
 
@@ -311,8 +315,8 @@ aoechr_exit(void)
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(chardevs); ++i)
-		device_destroy(aoe_class, MKDEV(AOE_MAJOR, chardevs[i].minor));
-	class_destroy(aoe_class);
+		device_destroy(&aoe_class, MKDEV(AOE_MAJOR, chardevs[i].minor));
+	class_unregister(&aoe_class);
 	unregister_chrdev(AOE_MAJOR, "aoechr");
 }
 
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 9deb4df6bdb8..cd738cab725f 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -442,13 +442,13 @@ static void fd_times_out(struct timer_list *unused);
 static void finish_fdc( void );
 static void finish_fdc_done( int dummy );
 static void setup_req_params( int drive );
-static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
-                     cmd, unsigned long param);
+static int fd_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
+		unsigned int cmd, unsigned long param);
 static void fd_probe( int drive );
 static int fd_test_drive_present( int drive );
 static void config_types( void );
-static int floppy_open(struct block_device *bdev, fmode_t mode);
-static void floppy_release(struct gendisk *disk, fmode_t mode);
+static int floppy_open(struct gendisk *disk, blk_mode_t mode);
+static void floppy_release(struct gendisk *disk);
 
 /************************* End of Prototypes **************************/
 
@@ -1581,7 +1581,7 @@ out:
 	return BLK_STS_OK;
 }
 
-static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
+static int fd_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
 		    unsigned int cmd, unsigned long param)
 {
 	struct gendisk *disk = bdev->bd_disk;
@@ -1760,15 +1760,15 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode,
 		/* invalidate the buffer track to force a reread */
 		BufferDrive = -1;
 		set_bit(drive, &fake_change);
-		if (bdev_check_media_change(bdev))
-			floppy_revalidate(bdev->bd_disk);
+		if (disk_check_media_change(disk))
+			floppy_revalidate(disk);
 		return 0;
 	default:
 		return -EINVAL;
 	}
 }
 
-static int fd_ioctl(struct block_device *bdev, fmode_t mode,
+static int fd_ioctl(struct block_device *bdev, blk_mode_t mode,
 			     unsigned int cmd, unsigned long arg)
 {
 	int ret;
@@ -1915,32 +1915,31 @@ static void __init config_types( void )
  * drive with different device numbers.
  */
 
-static int floppy_open(struct block_device *bdev, fmode_t mode)
+static int floppy_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct atari_floppy_struct *p = bdev->bd_disk->private_data;
-	int type  = MINOR(bdev->bd_dev) >> 2;
+	struct atari_floppy_struct *p = disk->private_data;
+	int type = disk->first_minor >> 2;
 
 	DPRINT(("fd_open: type=%d\n",type));
 	if (p->ref && p->type != type)
 		return -EBUSY;
 
-	if (p->ref == -1 || (p->ref && mode & FMODE_EXCL))
+	if (p->ref == -1 || (p->ref && mode & BLK_OPEN_EXCL))
 		return -EBUSY;
-
-	if (mode & FMODE_EXCL)
+	if (mode & BLK_OPEN_EXCL)
 		p->ref = -1;
 	else
 		p->ref++;
 
 	p->type = type;
 
-	if (mode & FMODE_NDELAY)
+	if (mode & BLK_OPEN_NDELAY)
 		return 0;
 
-	if (mode & (FMODE_READ|FMODE_WRITE)) {
-		if (bdev_check_media_change(bdev))
-			floppy_revalidate(bdev->bd_disk);
-		if (mode & FMODE_WRITE) {
+	if (mode & (BLK_OPEN_READ | BLK_OPEN_WRITE)) {
+		if (disk_check_media_change(disk))
+			floppy_revalidate(disk);
+		if (mode & BLK_OPEN_WRITE) {
 			if (p->wpstat) {
 				if (p->ref < 0)
 					p->ref = 0;
@@ -1953,18 +1952,18 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
-static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+static int floppy_unlocked_open(struct gendisk *disk, blk_mode_t mode)
 {
 	int ret;
 
 	mutex_lock(&ataflop_mutex);
-	ret = floppy_open(bdev, mode);
+	ret = floppy_open(disk, mode);
 	mutex_unlock(&ataflop_mutex);
 
 	return ret;
 }
 
-static void floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk)
 {
 	struct atari_floppy_struct *p = disk->private_data;
 	mutex_lock(&ataflop_mutex);
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index bcad9b926b0c..970bd6ff38c4 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -19,7 +19,7 @@
 #include <linux/highmem.h>
 #include <linux/mutex.h>
 #include <linux/pagemap.h>
-#include <linux/radix-tree.h>
+#include <linux/xarray.h>
 #include <linux/fs.h>
 #include <linux/slab.h>
 #include <linux/backing-dev.h>
@@ -28,7 +28,7 @@
 #include <linux/uaccess.h>
 
 /*
- * Each block ramdisk device has a radix_tree brd_pages of pages that stores
+ * Each block ramdisk device has a xarray brd_pages of pages that stores
  * the pages containing the block device's contents. A brd page's ->index is
  * its offset in PAGE_SIZE units. This is similar to, but in no way connected
  * with, the kernel's pagecache or buffer cache (which sit above our block
@@ -40,11 +40,9 @@ struct brd_device {
 	struct list_head	brd_list;
 
 	/*
-	 * Backing store of pages and lock to protect it. This is the contents
-	 * of the block device.
+	 * Backing store of pages. This is the contents of the block device.
 	 */
-	spinlock_t		brd_lock;
-	struct radix_tree_root	brd_pages;
+	struct xarray	        brd_pages;
 	u64			brd_nr_pages;
 };
 
@@ -56,21 +54,8 @@ static struct page *brd_lookup_page(struct brd_device *brd, sector_t sector)
 	pgoff_t idx;
 	struct page *page;
 
-	/*
-	 * The page lifetime is protected by the fact that we have opened the
-	 * device node -- brd pages will never be deleted under us, so we
-	 * don't need any further locking or refcounting.
-	 *
-	 * This is strictly true for the radix-tree nodes as well (ie. we
-	 * don't actually need the rcu_read_lock()), however that is not a
-	 * documented feature of the radix-tree API so it is better to be
-	 * safe here (we don't have total exclusion from radix tree updates
-	 * here, only deletes).
-	 */
-	rcu_read_lock();
 	idx = sector >> PAGE_SECTORS_SHIFT; /* sector to page index */
-	page = radix_tree_lookup(&brd->brd_pages, idx);
-	rcu_read_unlock();
+	page = xa_load(&brd->brd_pages, idx);
 
 	BUG_ON(page && page->index != idx);
 
@@ -83,7 +68,7 @@ static struct page *brd_lookup_page(struct brd_device *brd, sector_t sector)
 static int brd_insert_page(struct brd_device *brd, sector_t sector, gfp_t gfp)
 {
 	pgoff_t idx;
-	struct page *page;
+	struct page *page, *cur;
 	int ret = 0;
 
 	page = brd_lookup_page(brd, sector);
@@ -94,71 +79,42 @@ static int brd_insert_page(struct brd_device *brd, sector_t sector, gfp_t gfp)
 	if (!page)
 		return -ENOMEM;
 
-	if (radix_tree_maybe_preload(gfp)) {
-		__free_page(page);
-		return -ENOMEM;
-	}
+	xa_lock(&brd->brd_pages);
 
-	spin_lock(&brd->brd_lock);
 	idx = sector >> PAGE_SECTORS_SHIFT;
 	page->index = idx;
-	if (radix_tree_insert(&brd->brd_pages, idx, page)) {
+
+	cur = __xa_cmpxchg(&brd->brd_pages, idx, NULL, page, gfp);
+
+	if (unlikely(cur)) {
 		__free_page(page);
-		page = radix_tree_lookup(&brd->brd_pages, idx);
-		if (!page)
-			ret = -ENOMEM;
-		else if (page->index != idx)
+		ret = xa_err(cur);
+		if (!ret && (cur->index != idx))
 			ret = -EIO;
 	} else {
 		brd->brd_nr_pages++;
 	}
-	spin_unlock(&brd->brd_lock);
 
-	radix_tree_preload_end();
+	xa_unlock(&brd->brd_pages);
+
 	return ret;
 }
 
 /*
- * Free all backing store pages and radix tree. This must only be called when
+ * Free all backing store pages and xarray. This must only be called when
  * there are no other users of the device.
  */
-#define FREE_BATCH 16
 static void brd_free_pages(struct brd_device *brd)
 {
-	unsigned long pos = 0;
-	struct page *pages[FREE_BATCH];
-	int nr_pages;
-
-	do {
-		int i;
-
-		nr_pages = radix_tree_gang_lookup(&brd->brd_pages,
-				(void **)pages, pos, FREE_BATCH);
-
-		for (i = 0; i < nr_pages; i++) {
-			void *ret;
-
-			BUG_ON(pages[i]->index < pos);
-			pos = pages[i]->index;
-			ret = radix_tree_delete(&brd->brd_pages, pos);
-			BUG_ON(!ret || ret != pages[i]);
-			__free_page(pages[i]);
-		}
-
-		pos++;
+	struct page *page;
+	pgoff_t idx;
 
-		/*
-		 * It takes 3.4 seconds to remove 80GiB ramdisk.
-		 * So, we need cond_resched to avoid stalling the CPU.
-		 */
+	xa_for_each(&brd->brd_pages, idx, page) {
+		__free_page(page);
 		cond_resched();
+	}
 
-		/*
-		 * This assumes radix_tree_gang_lookup always returns as
-		 * many pages as possible. If the radix-tree code changes,
-		 * so will this have to.
-		 */
-	} while (nr_pages == FREE_BATCH);
+	xa_destroy(&brd->brd_pages);
 }
 
 /*
@@ -372,8 +328,7 @@ static int brd_alloc(int i)
 	brd->brd_number		= i;
 	list_add_tail(&brd->brd_list, &brd_devices);
 
-	spin_lock_init(&brd->brd_lock);
-	INIT_RADIX_TREE(&brd->brd_pages, GFP_ATOMIC);
+	xa_init(&brd->brd_pages);
 
 	snprintf(buf, DISK_NAME_LEN, "ram%d", i);
 	if (!IS_ERR_OR_NULL(brd_debugfs_dir))
diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index 6ac8c54b44c7..85ca000a0564 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -1043,9 +1043,7 @@ static void bm_page_io_async(struct drbd_bm_aio_ctx *ctx, int page_nr) __must_ho
 	bio = bio_alloc_bioset(device->ldev->md_bdev, 1, op, GFP_NOIO,
 			&drbd_md_io_bio_set);
 	bio->bi_iter.bi_sector = on_disk_sector;
-	/* bio_add_page of a single page to an empty bio will always succeed,
-	 * according to api.  Do we want to assert that? */
-	bio_add_page(bio, page, len, 0);
+	__bio_add_page(bio, page, len, 0);
 	bio->bi_private = ctx;
 	bio->bi_end_io = drbd_bm_endio;
 
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 83987e7a5ef2..965f672557f2 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -37,7 +37,6 @@
 #include <linux/notifier.h>
 #include <linux/kthread.h>
 #include <linux/workqueue.h>
-#define __KERNEL_SYSCALLS__
 #include <linux/unistd.h>
 #include <linux/vmalloc.h>
 #include <linux/sched/signal.h>
@@ -50,8 +49,8 @@
 #include "drbd_debugfs.h"
 
 static DEFINE_MUTEX(drbd_main_mutex);
-static int drbd_open(struct block_device *bdev, fmode_t mode);
-static void drbd_release(struct gendisk *gd, fmode_t mode);
+static int drbd_open(struct gendisk *disk, blk_mode_t mode);
+static void drbd_release(struct gendisk *gd);
 static void md_sync_timer_fn(struct timer_list *t);
 static int w_bitmap_io(struct drbd_work *w, int unused);
 
@@ -1883,9 +1882,9 @@ int drbd_send_all(struct drbd_connection *connection, struct socket *sock, void
 	return 0;
 }
 
-static int drbd_open(struct block_device *bdev, fmode_t mode)
+static int drbd_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct drbd_device *device = bdev->bd_disk->private_data;
+	struct drbd_device *device = disk->private_data;
 	unsigned long flags;
 	int rv = 0;
 
@@ -1895,7 +1894,7 @@ static int drbd_open(struct block_device *bdev, fmode_t mode)
 	 * and no race with updating open_cnt */
 
 	if (device->state.role != R_PRIMARY) {
-		if (mode & FMODE_WRITE)
+		if (mode & BLK_OPEN_WRITE)
 			rv = -EROFS;
 		else if (!drbd_allow_oos)
 			rv = -EMEDIUMTYPE;
@@ -1909,9 +1908,10 @@ static int drbd_open(struct block_device *bdev, fmode_t mode)
 	return rv;
 }
 
-static void drbd_release(struct gendisk *gd, fmode_t mode)
+static void drbd_release(struct gendisk *gd)
 {
 	struct drbd_device *device = gd->private_data;
+
 	mutex_lock(&drbd_main_mutex);
 	device->open_cnt--;
 	mutex_unlock(&drbd_main_mutex);
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index 1a5d3d72d91d..cddae6f4b00f 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -1640,8 +1640,8 @@ static struct block_device *open_backing_dev(struct drbd_device *device,
 	struct block_device *bdev;
 	int err = 0;
 
-	bdev = blkdev_get_by_path(bdev_path,
-				  FMODE_READ | FMODE_WRITE | FMODE_EXCL, claim_ptr);
+	bdev = blkdev_get_by_path(bdev_path, BLK_OPEN_READ | BLK_OPEN_WRITE,
+				  claim_ptr, NULL);
 	if (IS_ERR(bdev)) {
 		drbd_err(device, "open(\"%s\") failed with %ld\n",
 				bdev_path, PTR_ERR(bdev));
@@ -1653,7 +1653,7 @@ static struct block_device *open_backing_dev(struct drbd_device *device,
 
 	err = bd_link_disk_holder(bdev, device->vdisk);
 	if (err) {
-		blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+		blkdev_put(bdev, claim_ptr);
 		drbd_err(device, "bd_link_disk_holder(\"%s\", ...) failed with %d\n",
 				bdev_path, err);
 		bdev = ERR_PTR(err);
@@ -1695,13 +1695,13 @@ static int open_backing_devices(struct drbd_device *device,
 }
 
 static void close_backing_dev(struct drbd_device *device, struct block_device *bdev,
-	bool do_bd_unlink)
+		void *claim_ptr, bool do_bd_unlink)
 {
 	if (!bdev)
 		return;
 	if (do_bd_unlink)
 		bd_unlink_disk_holder(bdev, device->vdisk);
-	blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+	blkdev_put(bdev, claim_ptr);
 }
 
 void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *ldev)
@@ -1709,8 +1709,11 @@ void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *
 	if (ldev == NULL)
 		return;
 
-	close_backing_dev(device, ldev->md_bdev, ldev->md_bdev != ldev->backing_bdev);
-	close_backing_dev(device, ldev->backing_bdev, true);
+	close_backing_dev(device, ldev->md_bdev,
+			  ldev->md.meta_dev_idx < 0 ?
+				(void *)device : (void *)drbd_m_holder,
+			  ldev->md_bdev != ldev->backing_bdev);
+	close_backing_dev(device, ldev->backing_bdev, device, true);
 
 	kfree(ldev->disk_conf);
 	kfree(ldev);
@@ -2126,8 +2129,11 @@ int drbd_adm_attach(struct sk_buff *skb, struct genl_info *info)
  fail:
 	conn_reconfig_done(connection);
 	if (nbc) {
-		close_backing_dev(device, nbc->md_bdev, nbc->md_bdev != nbc->backing_bdev);
-		close_backing_dev(device, nbc->backing_bdev, true);
+		close_backing_dev(device, nbc->md_bdev,
+			  nbc->disk_conf->meta_dev_idx < 0 ?
+				(void *)device : (void *)drbd_m_holder,
+			  nbc->md_bdev != nbc->backing_bdev);
+		close_backing_dev(device, nbc->backing_bdev, device, true);
 		kfree(nbc);
 	}
 	kfree(new_disk_conf);
diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c
index 8c2bc47de473..0c9f54197768 100644
--- a/drivers/block/drbd/drbd_receiver.c
+++ b/drivers/block/drbd/drbd_receiver.c
@@ -27,7 +27,6 @@
 #include <uapi/linux/sched/types.h>
 #include <linux/sched/signal.h>
 #include <linux/pkt_sched.h>
-#define __KERNEL_SYSCALLS__
 #include <linux/unistd.h>
 #include <linux/vmalloc.h>
 #include <linux/random.h>
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index cec2c20f5e59..2db9b186b977 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -402,7 +402,7 @@ 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 blk_mq_tag_set tag_sets[N_DRIVE];
-static struct block_device *opened_bdev[N_DRIVE];
+static struct gendisk *opened_disk[N_DRIVE];
 static DEFINE_MUTEX(open_lock);
 static struct floppy_raw_cmd *raw_cmd, default_raw_cmd;
 
@@ -3210,13 +3210,13 @@ static int floppy_raw_cmd_ioctl(int type, int drive, int cmd,
 
 #endif
 
-static int invalidate_drive(struct block_device *bdev)
+static int invalidate_drive(struct gendisk *disk)
 {
 	/* invalidate the buffer track to force a reread */
-	set_bit((long)bdev->bd_disk->private_data, &fake_change);
+	set_bit((long)disk->private_data, &fake_change);
 	process_fd_request();
-	if (bdev_check_media_change(bdev))
-		floppy_revalidate(bdev->bd_disk);
+	if (disk_check_media_change(disk))
+		floppy_revalidate(disk);
 	return 0;
 }
 
@@ -3251,10 +3251,11 @@ static int set_geometry(unsigned int cmd, struct floppy_struct *g,
 			    floppy_type[type].size + 1;
 		process_fd_request();
 		for (cnt = 0; cnt < N_DRIVE; cnt++) {
-			struct block_device *bdev = opened_bdev[cnt];
-			if (!bdev || ITYPE(drive_state[cnt].fd_device) != type)
+			struct gendisk *disk = opened_disk[cnt];
+
+			if (!disk || ITYPE(drive_state[cnt].fd_device) != type)
 				continue;
-			__invalidate_device(bdev, true);
+			__invalidate_device(disk->part0, true);
 		}
 		mutex_unlock(&open_lock);
 	} else {
@@ -3287,7 +3288,7 @@ static int set_geometry(unsigned int cmd, struct floppy_struct *g,
 		    drive_state[current_drive].maxtrack ||
 		    ((user_params[drive].sect ^ oldStretch) &
 		     (FD_SWAPSIDES | FD_SECTBASEMASK)))
-			invalidate_drive(bdev);
+			invalidate_drive(bdev->bd_disk);
 		else
 			process_fd_request();
 	}
@@ -3393,8 +3394,8 @@ static bool valid_floppy_drive_params(const short autodetect[FD_AUTODETECT_SIZE]
 	return true;
 }
 
-static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
-		    unsigned long param)
+static int fd_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
+		unsigned int cmd, unsigned long param)
 {
 	int drive = (long)bdev->bd_disk->private_data;
 	int type = ITYPE(drive_state[drive].fd_device);
@@ -3427,7 +3428,8 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
 		return ret;
 
 	/* permission checks */
-	if (((cmd & 0x40) && !(mode & (FMODE_WRITE | FMODE_WRITE_IOCTL))) ||
+	if (((cmd & 0x40) &&
+	     !(mode & (BLK_OPEN_WRITE | BLK_OPEN_WRITE_IOCTL))) ||
 	    ((cmd & 0x80) && !capable(CAP_SYS_ADMIN)))
 		return -EPERM;
 
@@ -3464,7 +3466,7 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
 		current_type[drive] = NULL;
 		floppy_sizes[drive] = MAX_DISK_SIZE << 1;
 		drive_state[drive].keep_data = 0;
-		return invalidate_drive(bdev);
+		return invalidate_drive(bdev->bd_disk);
 	case FDSETPRM:
 	case FDDEFPRM:
 		return set_geometry(cmd, &inparam.g, drive, type, bdev);
@@ -3503,7 +3505,7 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
 	case FDFLUSH:
 		if (lock_fdc(drive))
 			return -EINTR;
-		return invalidate_drive(bdev);
+		return invalidate_drive(bdev->bd_disk);
 	case FDSETEMSGTRESH:
 		drive_params[drive].max_errors.reporting = (unsigned short)(param & 0x0f);
 		return 0;
@@ -3565,7 +3567,7 @@ static int fd_locked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int
 	return 0;
 }
 
-static int fd_ioctl(struct block_device *bdev, fmode_t mode,
+static int fd_ioctl(struct block_device *bdev, blk_mode_t mode,
 			     unsigned int cmd, unsigned long param)
 {
 	int ret;
@@ -3653,8 +3655,8 @@ struct compat_floppy_write_errors {
 #define FDGETFDCSTAT32 _IOR(2, 0x15, struct compat_floppy_fdc_state)
 #define FDWERRORGET32  _IOR(2, 0x17, struct compat_floppy_write_errors)
 
-static int compat_set_geometry(struct block_device *bdev, fmode_t mode, unsigned int cmd,
-		    struct compat_floppy_struct __user *arg)
+static int compat_set_geometry(struct block_device *bdev, blk_mode_t mode,
+		unsigned int cmd, struct compat_floppy_struct __user *arg)
 {
 	struct floppy_struct v;
 	int drive, type;
@@ -3663,7 +3665,7 @@ static int compat_set_geometry(struct block_device *bdev, fmode_t mode, unsigned
 	BUILD_BUG_ON(offsetof(struct floppy_struct, name) !=
 		     offsetof(struct compat_floppy_struct, name));
 
-	if (!(mode & (FMODE_WRITE | FMODE_WRITE_IOCTL)))
+	if (!(mode & (BLK_OPEN_WRITE | BLK_OPEN_WRITE_IOCTL)))
 		return -EPERM;
 
 	memset(&v, 0, sizeof(struct floppy_struct));
@@ -3860,8 +3862,8 @@ static int compat_werrorget(int drive,
 	return 0;
 }
 
-static int fd_compat_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
-		    unsigned long param)
+static int fd_compat_ioctl(struct block_device *bdev, blk_mode_t mode,
+		unsigned int cmd, unsigned long param)
 {
 	int drive = (long)bdev->bd_disk->private_data;
 	switch (cmd) {
@@ -3962,7 +3964,7 @@ static void __init config_types(void)
 		pr_cont("\n");
 }
 
-static void floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk)
 {
 	int drive = (long)disk->private_data;
 
@@ -3973,7 +3975,7 @@ static void floppy_release(struct gendisk *disk, fmode_t mode)
 		drive_state[drive].fd_ref = 0;
 	}
 	if (!drive_state[drive].fd_ref)
-		opened_bdev[drive] = NULL;
+		opened_disk[drive] = NULL;
 	mutex_unlock(&open_lock);
 	mutex_unlock(&floppy_mutex);
 }
@@ -3983,9 +3985,9 @@ static void floppy_release(struct gendisk *disk, fmode_t mode)
  * /dev/PS0 etc), and disallows simultaneous access to the same
  * drive with different device numbers.
  */
-static int floppy_open(struct block_device *bdev, fmode_t mode)
+static int floppy_open(struct gendisk *disk, blk_mode_t mode)
 {
-	int drive = (long)bdev->bd_disk->private_data;
+	int drive = (long)disk->private_data;
 	int old_dev, new_dev;
 	int try;
 	int res = -EBUSY;
@@ -3994,7 +3996,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	mutex_lock(&floppy_mutex);
 	mutex_lock(&open_lock);
 	old_dev = drive_state[drive].fd_device;
-	if (opened_bdev[drive] && opened_bdev[drive] != bdev)
+	if (opened_disk[drive] && opened_disk[drive] != disk)
 		goto out2;
 
 	if (!drive_state[drive].fd_ref && (drive_params[drive].flags & FD_BROKEN_DCL)) {
@@ -4004,7 +4006,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 
 	drive_state[drive].fd_ref++;
 
-	opened_bdev[drive] = bdev;
+	opened_disk[drive] = disk;
 
 	res = -ENXIO;
 
@@ -4038,7 +4040,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 		}
 	}
 
-	new_dev = MINOR(bdev->bd_dev);
+	new_dev = disk->first_minor;
 	drive_state[drive].fd_device = new_dev;
 	set_capacity(disks[drive][ITYPE(new_dev)], floppy_sizes[new_dev]);
 	if (old_dev != -1 && old_dev != new_dev) {
@@ -4048,21 +4050,20 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 
 	if (fdc_state[FDC(drive)].rawcmd == 1)
 		fdc_state[FDC(drive)].rawcmd = 2;
-
-	if (!(mode & FMODE_NDELAY)) {
-		if (mode & (FMODE_READ|FMODE_WRITE)) {
+	if (!(mode & BLK_OPEN_NDELAY)) {
+		if (mode & (BLK_OPEN_READ | BLK_OPEN_WRITE)) {
 			drive_state[drive].last_checked = 0;
 			clear_bit(FD_OPEN_SHOULD_FAIL_BIT,
 				  &drive_state[drive].flags);
-			if (bdev_check_media_change(bdev))
-				floppy_revalidate(bdev->bd_disk);
+			if (disk_check_media_change(disk))
+				floppy_revalidate(disk);
 			if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags))
 				goto out;
 			if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags))
 				goto out;
 		}
 		res = -EROFS;
-		if ((mode & FMODE_WRITE) &&
+		if ((mode & BLK_OPEN_WRITE) &&
 		    !test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags))
 			goto out;
 	}
@@ -4073,7 +4074,7 @@ out:
 	drive_state[drive].fd_ref--;
 
 	if (!drive_state[drive].fd_ref)
-		opened_bdev[drive] = NULL;
+		opened_disk[drive] = NULL;
 out2:
 	mutex_unlock(&open_lock);
 	mutex_unlock(&floppy_mutex);
@@ -4147,7 +4148,7 @@ static int __floppy_read_block_0(struct block_device *bdev, int drive)
 	cbdata.drive = drive;
 
 	bio_init(&bio, bdev, &bio_vec, 1, REQ_OP_READ);
-	bio_add_page(&bio, page, block_size(bdev), 0);
+	__bio_add_page(&bio, page, block_size(bdev), 0);
 
 	bio.bi_iter.bi_sector = 0;
 	bio.bi_flags |= (1 << BIO_QUIET);
@@ -4203,7 +4204,8 @@ static int floppy_revalidate(struct gendisk *disk)
 			drive_state[drive].generation++;
 		if (drive_no_geom(drive)) {
 			/* auto-sensing */
-			res = __floppy_read_block_0(opened_bdev[drive], drive);
+			res = __floppy_read_block_0(opened_disk[drive]->part0,
+						    drive);
 		} else {
 			if (cf)
 				poll_drive(false, FD_RAW_NEED_DISK);
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index bc31bb7072a2..37511d2b2caf 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -990,7 +990,7 @@ loop_set_status_from_info(struct loop_device *lo,
 	return 0;
 }
 
-static int loop_configure(struct loop_device *lo, fmode_t mode,
+static int loop_configure(struct loop_device *lo, blk_mode_t mode,
 			  struct block_device *bdev,
 			  const struct loop_config *config)
 {
@@ -1014,8 +1014,8 @@ static int loop_configure(struct loop_device *lo, fmode_t mode,
 	 * If we don't hold exclusive handle for the device, upgrade to it
 	 * here to avoid changing device under exclusive owner.
 	 */
-	if (!(mode & FMODE_EXCL)) {
-		error = bd_prepare_to_claim(bdev, loop_configure);
+	if (!(mode & BLK_OPEN_EXCL)) {
+		error = bd_prepare_to_claim(bdev, loop_configure, NULL);
 		if (error)
 			goto out_putf;
 	}
@@ -1050,7 +1050,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode,
 	if (error)
 		goto out_unlock;
 
-	if (!(file->f_mode & FMODE_WRITE) || !(mode & FMODE_WRITE) ||
+	if (!(file->f_mode & FMODE_WRITE) || !(mode & BLK_OPEN_WRITE) ||
 	    !file->f_op->write_iter)
 		lo->lo_flags |= LO_FLAGS_READ_ONLY;
 
@@ -1116,7 +1116,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode,
 	if (partscan)
 		loop_reread_partitions(lo);
 
-	if (!(mode & FMODE_EXCL))
+	if (!(mode & BLK_OPEN_EXCL))
 		bd_abort_claiming(bdev, loop_configure);
 
 	return 0;
@@ -1124,7 +1124,7 @@ static int loop_configure(struct loop_device *lo, fmode_t mode,
 out_unlock:
 	loop_global_unlock(lo, is_loop);
 out_bdev:
-	if (!(mode & FMODE_EXCL))
+	if (!(mode & BLK_OPEN_EXCL))
 		bd_abort_claiming(bdev, loop_configure);
 out_putf:
 	fput(file);
@@ -1528,7 +1528,7 @@ static int lo_simple_ioctl(struct loop_device *lo, unsigned int cmd,
 	return err;
 }
 
-static int lo_ioctl(struct block_device *bdev, fmode_t mode,
+static int lo_ioctl(struct block_device *bdev, blk_mode_t mode,
 	unsigned int cmd, unsigned long arg)
 {
 	struct loop_device *lo = bdev->bd_disk->private_data;
@@ -1563,24 +1563,22 @@ static int lo_ioctl(struct block_device *bdev, fmode_t mode,
 		return loop_clr_fd(lo);
 	case LOOP_SET_STATUS:
 		err = -EPERM;
-		if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) {
+		if ((mode & BLK_OPEN_WRITE) || capable(CAP_SYS_ADMIN))
 			err = loop_set_status_old(lo, argp);
-		}
 		break;
 	case LOOP_GET_STATUS:
 		return loop_get_status_old(lo, argp);
 	case LOOP_SET_STATUS64:
 		err = -EPERM;
-		if ((mode & FMODE_WRITE) || capable(CAP_SYS_ADMIN)) {
+		if ((mode & BLK_OPEN_WRITE) || capable(CAP_SYS_ADMIN))
 			err = loop_set_status64(lo, argp);
-		}
 		break;
 	case LOOP_GET_STATUS64:
 		return loop_get_status64(lo, argp);
 	case LOOP_SET_CAPACITY:
 	case LOOP_SET_DIRECT_IO:
 	case LOOP_SET_BLOCK_SIZE:
-		if (!(mode & FMODE_WRITE) && !capable(CAP_SYS_ADMIN))
+		if (!(mode & BLK_OPEN_WRITE) && !capable(CAP_SYS_ADMIN))
 			return -EPERM;
 		fallthrough;
 	default:
@@ -1691,7 +1689,7 @@ loop_get_status_compat(struct loop_device *lo,
 	return err;
 }
 
-static int lo_compat_ioctl(struct block_device *bdev, fmode_t mode,
+static int lo_compat_ioctl(struct block_device *bdev, blk_mode_t mode,
 			   unsigned int cmd, unsigned long arg)
 {
 	struct loop_device *lo = bdev->bd_disk->private_data;
@@ -1727,7 +1725,7 @@ static int lo_compat_ioctl(struct block_device *bdev, fmode_t mode,
 }
 #endif
 
-static void lo_release(struct gendisk *disk, fmode_t mode)
+static void lo_release(struct gendisk *disk)
 {
 	struct loop_device *lo = disk->private_data;
 
diff --git a/drivers/block/mtip32xx/mtip32xx.c b/drivers/block/mtip32xx/mtip32xx.c
index 815d77ba6381..b200950e8fb5 100644
--- a/drivers/block/mtip32xx/mtip32xx.c
+++ b/drivers/block/mtip32xx/mtip32xx.c
@@ -3041,7 +3041,7 @@ static int rssd_disk_name_format(char *prefix,
  *                 structure pointer.
  */
 static int mtip_block_ioctl(struct block_device *dev,
-			    fmode_t mode,
+			    blk_mode_t mode,
 			    unsigned cmd,
 			    unsigned long arg)
 {
@@ -3079,7 +3079,7 @@ static int mtip_block_ioctl(struct block_device *dev,
  *                 structure pointer.
  */
 static int mtip_block_compat_ioctl(struct block_device *dev,
-			    fmode_t mode,
+			    blk_mode_t mode,
 			    unsigned cmd,
 			    unsigned long arg)
 {
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 65ecde3e2a5b..8576d696c7a2 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -1502,7 +1502,7 @@ static int __nbd_ioctl(struct block_device *bdev, struct nbd_device *nbd,
 	return -ENOTTY;
 }
 
-static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
+static int nbd_ioctl(struct block_device *bdev, blk_mode_t mode,
 		     unsigned int cmd, unsigned long arg)
 {
 	struct nbd_device *nbd = bdev->bd_disk->private_data;
@@ -1553,13 +1553,13 @@ static struct nbd_config *nbd_alloc_config(void)
 	return config;
 }
 
-static int nbd_open(struct block_device *bdev, fmode_t mode)
+static int nbd_open(struct gendisk *disk, blk_mode_t mode)
 {
 	struct nbd_device *nbd;
 	int ret = 0;
 
 	mutex_lock(&nbd_index_mutex);
-	nbd = bdev->bd_disk->private_data;
+	nbd = disk->private_data;
 	if (!nbd) {
 		ret = -ENXIO;
 		goto out;
@@ -1587,17 +1587,17 @@ static int nbd_open(struct block_device *bdev, fmode_t mode)
 		refcount_inc(&nbd->refs);
 		mutex_unlock(&nbd->config_lock);
 		if (max_part)
-			set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
+			set_bit(GD_NEED_PART_SCAN, &disk->state);
 	} else if (nbd_disconnected(nbd->config)) {
 		if (max_part)
-			set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
+			set_bit(GD_NEED_PART_SCAN, &disk->state);
 	}
 out:
 	mutex_unlock(&nbd_index_mutex);
 	return ret;
 }
 
-static void nbd_release(struct gendisk *disk, fmode_t mode)
+static void nbd_release(struct gendisk *disk)
 {
 	struct nbd_device *nbd = disk->private_data;
 
@@ -1776,7 +1776,8 @@ static struct nbd_device *nbd_dev_add(int index, unsigned int refs)
 		if (err == -ENOSPC)
 			err = -EEXIST;
 	} else {
-		err = idr_alloc(&nbd_index_idr, nbd, 0, 0, GFP_KERNEL);
+		err = idr_alloc(&nbd_index_idr, nbd, 0,
+				(MINORMASK >> part_shift) + 1, GFP_KERNEL);
 		if (err >= 0)
 			index = err;
 	}
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index d5d7884cedd4..a1428538bda5 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -46,47 +46,34 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
-#include <linux/pktcdvd.h>
-#include <linux/module.h>
-#include <linux/types.h>
-#include <linux/kernel.h>
+#include <linux/backing-dev.h>
 #include <linux/compat.h>
-#include <linux/kthread.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
 #include <linux/errno.h>
-#include <linux/spinlock.h>
 #include <linux/file.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
-#include <linux/miscdevice.h>
 #include <linux/freezer.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
 #include <linux/mutex.h>
+#include <linux/nospec.h>
+#include <linux/pktcdvd.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 #include <linux/slab.h>
-#include <linux/backing-dev.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
 #include <scsi/scsi_ioctl.h>
-#include <scsi/scsi.h>
-#include <linux/debugfs.h>
-#include <linux/device.h>
-#include <linux/nospec.h>
-#include <linux/uaccess.h>
 
-#define DRIVER_NAME	"pktcdvd"
+#include <asm/unaligned.h>
 
-#define pkt_err(pd, fmt, ...)						\
-	pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
-#define pkt_notice(pd, fmt, ...)					\
-	pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
-#define pkt_info(pd, fmt, ...)						\
-	pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
-
-#define pkt_dbg(level, pd, fmt, ...)					\
-do {									\
-	if (level == 2 && PACKET_DEBUG >= 2)				\
-		pr_notice("%s: %s():" fmt,				\
-			  pd->name, __func__, ##__VA_ARGS__);		\
-	else if (level == 1 && PACKET_DEBUG >= 1)			\
-		pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__);		\
-} while (0)
+#define DRIVER_NAME	"pktcdvd"
 
 #define MAX_SPEED 0xffff
 
@@ -107,7 +94,6 @@ static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
 /* forward declaration */
 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 static int pkt_remove_dev(dev_t pkt_dev);
-static int pkt_seq_show(struct seq_file *m, void *p);
 
 static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
 {
@@ -253,15 +239,16 @@ static ssize_t congestion_off_store(struct device *dev,
 				    const char *buf, size_t len)
 {
 	struct pktcdvd_device *pd = dev_get_drvdata(dev);
-	int val;
+	int val, ret;
 
-	if (sscanf(buf, "%d", &val) == 1) {
-		spin_lock(&pd->lock);
-		pd->write_congestion_off = val;
-		init_write_congestion_marks(&pd->write_congestion_off,
-					&pd->write_congestion_on);
-		spin_unlock(&pd->lock);
-	}
+	ret = kstrtoint(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	spin_lock(&pd->lock);
+	pd->write_congestion_off = val;
+	init_write_congestion_marks(&pd->write_congestion_off, &pd->write_congestion_on);
+	spin_unlock(&pd->lock);
 	return len;
 }
 static DEVICE_ATTR_RW(congestion_off);
@@ -283,15 +270,16 @@ static ssize_t congestion_on_store(struct device *dev,
 				   const char *buf, size_t len)
 {
 	struct pktcdvd_device *pd = dev_get_drvdata(dev);
-	int val;
+	int val, ret;
 
-	if (sscanf(buf, "%d", &val) == 1) {
-		spin_lock(&pd->lock);
-		pd->write_congestion_on = val;
-		init_write_congestion_marks(&pd->write_congestion_off,
-					&pd->write_congestion_on);
-		spin_unlock(&pd->lock);
-	}
+	ret = kstrtoint(buf, 10, &val);
+	if (ret)
+		return ret;
+
+	spin_lock(&pd->lock);
+	pd->write_congestion_on = val;
+	init_write_congestion_marks(&pd->write_congestion_off, &pd->write_congestion_on);
+	spin_unlock(&pd->lock);
 	return len;
 }
 static DEVICE_ATTR_RW(congestion_on);
@@ -319,7 +307,7 @@ static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 	if (class_is_registered(&class_pktcdvd)) {
 		pd->dev = device_create_with_groups(&class_pktcdvd, NULL,
 						    MKDEV(0, 0), pd, pkt_groups,
-						    "%s", pd->name);
+						    "%s", pd->disk->disk_name);
 		if (IS_ERR(pd->dev))
 			pd->dev = NULL;
 	}
@@ -349,8 +337,8 @@ static ssize_t device_map_show(const struct class *c, const struct class_attribu
 		struct pktcdvd_device *pd = pkt_devs[idx];
 		if (!pd)
 			continue;
-		n += sprintf(data+n, "%s %u:%u %u:%u\n",
-			pd->name,
+		n += sysfs_emit_at(data, n, "%s %u:%u %u:%u\n",
+			pd->disk->disk_name,
 			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 			MAJOR(pd->bdev->bd_dev),
 			MINOR(pd->bdev->bd_dev));
@@ -428,34 +416,92 @@ static void pkt_sysfs_cleanup(void)
 
  *******************************************************************/
 
-static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
+static void pkt_count_states(struct pktcdvd_device *pd, int *states)
 {
-	return pkt_seq_show(m, p);
+	struct packet_data *pkt;
+	int i;
+
+	for (i = 0; i < PACKET_NUM_STATES; i++)
+		states[i] = 0;
+
+	spin_lock(&pd->cdrw.active_list_lock);
+	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
+		states[pkt->state]++;
+	}
+	spin_unlock(&pd->cdrw.active_list_lock);
 }
 
-static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
+static int pkt_seq_show(struct seq_file *m, void *p)
 {
-	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
-}
+	struct pktcdvd_device *pd = m->private;
+	char *msg;
+	int states[PACKET_NUM_STATES];
 
-static const struct file_operations debug_fops = {
-	.open		= pkt_debugfs_fops_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= single_release,
-	.owner		= THIS_MODULE,
-};
+	seq_printf(m, "Writer %s mapped to %pg:\n", pd->disk->disk_name, pd->bdev);
+
+	seq_printf(m, "\nSettings:\n");
+	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
+
+	if (pd->settings.write_type == 0)
+		msg = "Packet";
+	else
+		msg = "Unknown";
+	seq_printf(m, "\twrite type:\t\t%s\n", msg);
+
+	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
+	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
+
+	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
+
+	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
+		msg = "Mode 1";
+	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
+		msg = "Mode 2";
+	else
+		msg = "Unknown";
+	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
+
+	seq_printf(m, "\nStatistics:\n");
+	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
+	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
+	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
+	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
+	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
+
+	seq_printf(m, "\nMisc:\n");
+	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
+	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
+	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
+	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
+	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
+	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
+
+	seq_printf(m, "\nQueue state:\n");
+	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
+	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
+	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", pd->current_sector);
+
+	pkt_count_states(pd, states);
+	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
+		   states[0], states[1], states[2], states[3], states[4], states[5]);
+
+	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
+			pd->write_congestion_off,
+			pd->write_congestion_on);
+	return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(pkt_seq);
 
 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 {
 	if (!pkt_debugfs_root)
 		return;
-	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
+	pd->dfs_d_root = debugfs_create_dir(pd->disk->disk_name, pkt_debugfs_root);
 	if (!pd->dfs_d_root)
 		return;
 
-	pd->dfs_f_info = debugfs_create_file("info", 0444,
-					     pd->dfs_d_root, pd, &debug_fops);
+	pd->dfs_f_info = debugfs_create_file("info", 0444, pd->dfs_d_root,
+					     pd, &pkt_seq_fops);
 }
 
 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
@@ -484,9 +530,11 @@ static void pkt_debugfs_cleanup(void)
 
 static void pkt_bio_finished(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
+
 	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
-		pkt_dbg(2, pd, "queue empty\n");
+		dev_dbg(ddev, "queue empty\n");
 		atomic_set(&pd->iosched.attention, 1);
 		wake_up(&pd->wqueue);
 	}
@@ -717,15 +765,16 @@ static const char *sense_key_string(__u8 index)
 static void pkt_dump_sense(struct pktcdvd_device *pd,
 			   struct packet_command *cgc)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct scsi_sense_hdr *sshdr = cgc->sshdr;
 
 	if (sshdr)
-		pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
+		dev_err(ddev, "%*ph - sense %02x.%02x.%02x (%s)\n",
 			CDROM_PACKET_SIZE, cgc->cmd,
 			sshdr->sense_key, sshdr->asc, sshdr->ascq,
 			sense_key_string(sshdr->sense_key));
 	else
-		pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
+		dev_err(ddev, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
 }
 
 /*
@@ -762,10 +811,8 @@ static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 	cgc.sshdr = &sshdr;
 	cgc.cmd[0] = GPCMD_SET_SPEED;
-	cgc.cmd[2] = (read_speed >> 8) & 0xff;
-	cgc.cmd[3] = read_speed & 0xff;
-	cgc.cmd[4] = (write_speed >> 8) & 0xff;
-	cgc.cmd[5] = write_speed & 0xff;
+	put_unaligned_be16(read_speed, &cgc.cmd[2]);
+	put_unaligned_be16(write_speed, &cgc.cmd[4]);
 
 	ret = pkt_generic_packet(pd, &cgc);
 	if (ret)
@@ -809,6 +856,7 @@ static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
  */
 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 
 	if (atomic_read(&pd->iosched.attention) == 0)
 		return;
@@ -836,7 +884,7 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 				need_write_seek = 0;
 			if (need_write_seek && reads_queued) {
 				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
-					pkt_dbg(2, pd, "write, waiting\n");
+					dev_dbg(ddev, "write, waiting\n");
 					break;
 				}
 				pkt_flush_cache(pd);
@@ -845,7 +893,7 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 		} else {
 			if (!reads_queued && writes_queued) {
 				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
-					pkt_dbg(2, pd, "read, waiting\n");
+					dev_dbg(ddev, "read, waiting\n");
 					break;
 				}
 				pd->iosched.writing = 1;
@@ -892,25 +940,27 @@ static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
  */
 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 {
-	if ((pd->settings.size << 9) / CD_FRAMESIZE
-	    <= queue_max_segments(q)) {
+	struct device *ddev = disk_to_dev(pd->disk);
+
+	if ((pd->settings.size << 9) / CD_FRAMESIZE <= queue_max_segments(q)) {
 		/*
 		 * The cdrom device can handle one segment/frame
 		 */
 		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 		return 0;
-	} else if ((pd->settings.size << 9) / PAGE_SIZE
-		   <= queue_max_segments(q)) {
+	}
+
+	if ((pd->settings.size << 9) / PAGE_SIZE <= queue_max_segments(q)) {
 		/*
 		 * We can handle this case at the expense of some extra memory
 		 * copies during write operations
 		 */
 		set_bit(PACKET_MERGE_SEGS, &pd->flags);
 		return 0;
-	} else {
-		pkt_err(pd, "cdrom max_phys_segments too small\n");
-		return -EIO;
 	}
+
+	dev_err(ddev, "cdrom max_phys_segments too small\n");
+	return -EIO;
 }
 
 static void pkt_end_io_read(struct bio *bio)
@@ -919,9 +969,8 @@ static void pkt_end_io_read(struct bio *bio)
 	struct pktcdvd_device *pd = pkt->pd;
 	BUG_ON(!pd);
 
-	pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n",
-		bio, (unsigned long long)pkt->sector,
-		(unsigned long long)bio->bi_iter.bi_sector, bio->bi_status);
+	dev_dbg(disk_to_dev(pd->disk), "bio=%p sec0=%llx sec=%llx err=%d\n",
+		bio, pkt->sector, bio->bi_iter.bi_sector, bio->bi_status);
 
 	if (bio->bi_status)
 		atomic_inc(&pkt->io_errors);
@@ -939,7 +988,7 @@ static void pkt_end_io_packet_write(struct bio *bio)
 	struct pktcdvd_device *pd = pkt->pd;
 	BUG_ON(!pd);
 
-	pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, bio->bi_status);
+	dev_dbg(disk_to_dev(pd->disk), "id=%d, err=%d\n", pkt->id, bio->bi_status);
 
 	pd->stats.pkt_ended++;
 
@@ -955,6 +1004,7 @@ static void pkt_end_io_packet_write(struct bio *bio)
  */
 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	int frames_read = 0;
 	struct bio *bio;
 	int f;
@@ -983,8 +1033,7 @@ static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 	spin_unlock(&pkt->lock);
 
 	if (pkt->cache_valid) {
-		pkt_dbg(2, pd, "zone %llx cached\n",
-			(unsigned long long)pkt->sector);
+		dev_dbg(ddev, "zone %llx cached\n", pkt->sector);
 		goto out_account;
 	}
 
@@ -1005,8 +1054,8 @@ static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 
 		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
 		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
-		pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n",
-			f, pkt->pages[p], offset);
+		dev_dbg(ddev, "Adding frame %d, page:%p offs:%d\n", f,
+			pkt->pages[p], offset);
 		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
 			BUG();
 
@@ -1016,8 +1065,7 @@ static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 	}
 
 out_account:
-	pkt_dbg(2, pd, "need %d frames for zone %llx\n",
-		frames_read, (unsigned long long)pkt->sector);
+	dev_dbg(ddev, "need %d frames for zone %llx\n", frames_read, pkt->sector);
 	pd->stats.pkt_started++;
 	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
 }
@@ -1051,17 +1099,17 @@ static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *p
 	}
 }
 
-static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
+static inline void pkt_set_state(struct device *ddev, struct packet_data *pkt,
+				 enum packet_data_state state)
 {
-#if PACKET_DEBUG > 1
 	static const char *state_name[] = {
 		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
 	};
 	enum packet_data_state old_state = pkt->state;
-	pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n",
-		pkt->id, (unsigned long long)pkt->sector,
-		state_name[old_state], state_name[state]);
-#endif
+
+	dev_dbg(ddev, "pkt %2d : s=%6llx %s -> %s\n",
+		pkt->id, pkt->sector, state_name[old_state], state_name[state]);
+
 	pkt->state = state;
 }
 
@@ -1071,6 +1119,7 @@ static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state
  */
 static int pkt_handle_queue(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_data *pkt, *p;
 	struct bio *bio = NULL;
 	sector_t zone = 0; /* Suppress gcc warning */
@@ -1080,7 +1129,7 @@ static int pkt_handle_queue(struct pktcdvd_device *pd)
 	atomic_set(&pd->scan_queue, 0);
 
 	if (list_empty(&pd->cdrw.pkt_free_list)) {
-		pkt_dbg(2, pd, "no pkt\n");
+		dev_dbg(ddev, "no pkt\n");
 		return 0;
 	}
 
@@ -1117,7 +1166,7 @@ try_next_bio:
 	}
 	spin_unlock(&pd->lock);
 	if (!bio) {
-		pkt_dbg(2, pd, "no bio\n");
+		dev_dbg(ddev, "no bio\n");
 		return 0;
 	}
 
@@ -1133,12 +1182,13 @@ try_next_bio:
 	 * to this packet.
 	 */
 	spin_lock(&pd->lock);
-	pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone);
+	dev_dbg(ddev, "looking for zone %llx\n", zone);
 	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
+		sector_t tmp = get_zone(node->bio->bi_iter.bi_sector, pd);
+
 		bio = node->bio;
-		pkt_dbg(2, pd, "found zone=%llx\n", (unsigned long long)
-			get_zone(bio->bi_iter.bi_sector, pd));
-		if (get_zone(bio->bi_iter.bi_sector, pd) != zone)
+		dev_dbg(ddev, "found zone=%llx\n", tmp);
+		if (tmp != zone)
 			break;
 		pkt_rbtree_erase(pd, node);
 		spin_lock(&pkt->lock);
@@ -1157,7 +1207,7 @@ try_next_bio:
 	spin_unlock(&pd->lock);
 
 	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
-	pkt_set_state(pkt, PACKET_WAITING_STATE);
+	pkt_set_state(ddev, pkt, PACKET_WAITING_STATE);
 	atomic_set(&pkt->run_sm, 1);
 
 	spin_lock(&pd->cdrw.active_list_lock);
@@ -1209,6 +1259,7 @@ static void bio_list_copy_data(struct bio *dst, struct bio *src)
  */
 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	int f;
 
 	bio_init(pkt->w_bio, pd->bdev, pkt->w_bio->bi_inline_vecs, pkt->frames,
@@ -1225,7 +1276,7 @@ static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 		if (!bio_add_page(pkt->w_bio, page, CD_FRAMESIZE, offset))
 			BUG();
 	}
-	pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
+	dev_dbg(ddev, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
 
 	/*
 	 * Fill-in bvec with data from orig_bios.
@@ -1233,11 +1284,10 @@ static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
 	spin_lock(&pkt->lock);
 	bio_list_copy_data(pkt->w_bio, pkt->orig_bios.head);
 
-	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
+	pkt_set_state(ddev, pkt, PACKET_WRITE_WAIT_STATE);
 	spin_unlock(&pkt->lock);
 
-	pkt_dbg(2, pd, "Writing %d frames for zone %llx\n",
-		pkt->write_size, (unsigned long long)pkt->sector);
+	dev_dbg(ddev, "Writing %d frames for zone %llx\n", pkt->write_size, pkt->sector);
 
 	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames))
 		pkt->cache_valid = 1;
@@ -1265,7 +1315,9 @@ static void pkt_finish_packet(struct packet_data *pkt, blk_status_t status)
 
 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
 {
-	pkt_dbg(2, pd, "pkt %d\n", pkt->id);
+	struct device *ddev = disk_to_dev(pd->disk);
+
+	dev_dbg(ddev, "pkt %d\n", pkt->id);
 
 	for (;;) {
 		switch (pkt->state) {
@@ -1275,7 +1327,7 @@ static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data
 
 			pkt->sleep_time = 0;
 			pkt_gather_data(pd, pkt);
-			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
+			pkt_set_state(ddev, pkt, PACKET_READ_WAIT_STATE);
 			break;
 
 		case PACKET_READ_WAIT_STATE:
@@ -1283,7 +1335,7 @@ static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data
 				return;
 
 			if (atomic_read(&pkt->io_errors) > 0) {
-				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
+				pkt_set_state(ddev, pkt, PACKET_RECOVERY_STATE);
 			} else {
 				pkt_start_write(pd, pkt);
 			}
@@ -1294,15 +1346,15 @@ static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data
 				return;
 
 			if (!pkt->w_bio->bi_status) {
-				pkt_set_state(pkt, PACKET_FINISHED_STATE);
+				pkt_set_state(ddev, pkt, PACKET_FINISHED_STATE);
 			} else {
-				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
+				pkt_set_state(ddev, pkt, PACKET_RECOVERY_STATE);
 			}
 			break;
 
 		case PACKET_RECOVERY_STATE:
-			pkt_dbg(2, pd, "No recovery possible\n");
-			pkt_set_state(pkt, PACKET_FINISHED_STATE);
+			dev_dbg(ddev, "No recovery possible\n");
+			pkt_set_state(ddev, pkt, PACKET_FINISHED_STATE);
 			break;
 
 		case PACKET_FINISHED_STATE:
@@ -1318,6 +1370,7 @@ static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data
 
 static void pkt_handle_packets(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_data *pkt, *next;
 
 	/*
@@ -1338,28 +1391,13 @@ static void pkt_handle_packets(struct pktcdvd_device *pd)
 		if (pkt->state == PACKET_FINISHED_STATE) {
 			list_del(&pkt->list);
 			pkt_put_packet_data(pd, pkt);
-			pkt_set_state(pkt, PACKET_IDLE_STATE);
+			pkt_set_state(ddev, pkt, PACKET_IDLE_STATE);
 			atomic_set(&pd->scan_queue, 1);
 		}
 	}
 	spin_unlock(&pd->cdrw.active_list_lock);
 }
 
-static void pkt_count_states(struct pktcdvd_device *pd, int *states)
-{
-	struct packet_data *pkt;
-	int i;
-
-	for (i = 0; i < PACKET_NUM_STATES; i++)
-		states[i] = 0;
-
-	spin_lock(&pd->cdrw.active_list_lock);
-	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
-		states[pkt->state]++;
-	}
-	spin_unlock(&pd->cdrw.active_list_lock);
-}
-
 /*
  * kcdrwd is woken up when writes have been queued for one of our
  * registered devices
@@ -1367,7 +1405,9 @@ static void pkt_count_states(struct pktcdvd_device *pd, int *states)
 static int kcdrwd(void *foobar)
 {
 	struct pktcdvd_device *pd = foobar;
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_data *pkt;
+	int states[PACKET_NUM_STATES];
 	long min_sleep_time, residue;
 
 	set_user_nice(current, MIN_NICE);
@@ -1398,13 +1438,9 @@ static int kcdrwd(void *foobar)
 				goto work_to_do;
 
 			/* Otherwise, go to sleep */
-			if (PACKET_DEBUG > 1) {
-				int states[PACKET_NUM_STATES];
-				pkt_count_states(pd, states);
-				pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
-					states[0], states[1], states[2],
-					states[3], states[4], states[5]);
-			}
+			pkt_count_states(pd, states);
+			dev_dbg(ddev, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
+				states[0], states[1], states[2], states[3], states[4], states[5]);
 
 			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
@@ -1412,9 +1448,9 @@ static int kcdrwd(void *foobar)
 					min_sleep_time = pkt->sleep_time;
 			}
 
-			pkt_dbg(2, pd, "sleeping\n");
+			dev_dbg(ddev, "sleeping\n");
 			residue = schedule_timeout(min_sleep_time);
-			pkt_dbg(2, pd, "wake up\n");
+			dev_dbg(ddev, "wake up\n");
 
 			/* make swsusp happy with our thread */
 			try_to_freeze();
@@ -1462,7 +1498,7 @@ work_to_do:
 
 static void pkt_print_settings(struct pktcdvd_device *pd)
 {
-	pkt_info(pd, "%s packets, %u blocks, Mode-%c disc\n",
+	dev_info(disk_to_dev(pd->disk), "%s packets, %u blocks, Mode-%c disc\n",
 		 pd->settings.fp ? "Fixed" : "Variable",
 		 pd->settings.size >> 2,
 		 pd->settings.block_mode == 8 ? '1' : '2');
@@ -1474,8 +1510,7 @@ static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc,
 
 	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
 	cgc->cmd[2] = page_code | (page_control << 6);
-	cgc->cmd[7] = cgc->buflen >> 8;
-	cgc->cmd[8] = cgc->buflen & 0xff;
+	put_unaligned_be16(cgc->buflen, &cgc->cmd[7]);
 	cgc->data_direction = CGC_DATA_READ;
 	return pkt_generic_packet(pd, cgc);
 }
@@ -1486,8 +1521,7 @@ static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc
 	memset(cgc->buffer, 0, 2);
 	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
 	cgc->cmd[1] = 0x10;		/* PF */
-	cgc->cmd[7] = cgc->buflen >> 8;
-	cgc->cmd[8] = cgc->buflen & 0xff;
+	put_unaligned_be16(cgc->buflen, &cgc->cmd[7]);
 	cgc->data_direction = CGC_DATA_WRITE;
 	return pkt_generic_packet(pd, cgc);
 }
@@ -1528,8 +1562,7 @@ static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type,
 	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
 	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
 	cgc.cmd[1] = type & 3;
-	cgc.cmd[4] = (track & 0xff00) >> 8;
-	cgc.cmd[5] = track & 0xff;
+	put_unaligned_be16(track, &cgc.cmd[4]);
 	cgc.cmd[8] = 8;
 	cgc.quiet = 1;
 
@@ -1590,6 +1623,7 @@ static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
  */
 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_command cgc;
 	struct scsi_sense_hdr sshdr;
 	write_param_page *wp;
@@ -1609,8 +1643,8 @@ static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
 		return ret;
 	}
 
-	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
-	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
+	size = 2 + get_unaligned_be16(&buffer[0]);
+	pd->mode_offset = get_unaligned_be16(&buffer[6]);
 	if (size > sizeof(buffer))
 		size = sizeof(buffer);
 
@@ -1656,7 +1690,7 @@ static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
 		/*
 		 * paranoia
 		 */
-		pkt_err(pd, "write mode wrong %d\n", wp->data_block_type);
+		dev_err(ddev, "write mode wrong %d\n", wp->data_block_type);
 		return 1;
 	}
 	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
@@ -1677,6 +1711,8 @@ static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
  */
 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
+
 	switch (pd->mmc3_profile) {
 		case 0x1a: /* DVD+RW */
 		case 0x12: /* DVD-RAM */
@@ -1701,7 +1737,7 @@ static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
 	if (ti->rt == 1 && ti->blank == 0)
 		return 1;
 
-	pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
+	dev_err(ddev, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
 	return 0;
 }
 
@@ -1710,6 +1746,8 @@ static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
  */
 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
+
 	switch (pd->mmc3_profile) {
 		case 0x0a: /* CD-RW */
 		case 0xffff: /* MMC3 not supported */
@@ -1719,8 +1757,7 @@ static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
 		case 0x12: /* DVD-RAM */
 			return 1;
 		default:
-			pkt_dbg(2, pd, "Wrong disc profile (%x)\n",
-				pd->mmc3_profile);
+			dev_dbg(ddev, "Wrong disc profile (%x)\n", pd->mmc3_profile);
 			return 0;
 	}
 
@@ -1729,22 +1766,22 @@ static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
 	 * but i'm not sure, should we leave this to user apps? probably.
 	 */
 	if (di->disc_type == 0xff) {
-		pkt_notice(pd, "unknown disc - no track?\n");
+		dev_notice(ddev, "unknown disc - no track?\n");
 		return 0;
 	}
 
 	if (di->disc_type != 0x20 && di->disc_type != 0) {
-		pkt_err(pd, "wrong disc type (%x)\n", di->disc_type);
+		dev_err(ddev, "wrong disc type (%x)\n", di->disc_type);
 		return 0;
 	}
 
 	if (di->erasable == 0) {
-		pkt_notice(pd, "disc not erasable\n");
+		dev_err(ddev, "disc not erasable\n");
 		return 0;
 	}
 
 	if (di->border_status == PACKET_SESSION_RESERVED) {
-		pkt_err(pd, "can't write to last track (reserved)\n");
+		dev_err(ddev, "can't write to last track (reserved)\n");
 		return 0;
 	}
 
@@ -1753,6 +1790,7 @@ static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
 
 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_command cgc;
 	unsigned char buf[12];
 	disc_information di;
@@ -1763,14 +1801,14 @@ static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
 	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
 	cgc.cmd[8] = 8;
 	ret = pkt_generic_packet(pd, &cgc);
-	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
+	pd->mmc3_profile = ret ? 0xffff : get_unaligned_be16(&buf[6]);
 
 	memset(&di, 0, sizeof(disc_information));
 	memset(&ti, 0, sizeof(track_information));
 
 	ret = pkt_get_disc_info(pd, &di);
 	if (ret) {
-		pkt_err(pd, "failed get_disc\n");
+		dev_err(ddev, "failed get_disc\n");
 		return ret;
 	}
 
@@ -1782,12 +1820,12 @@ static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
 	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
 	ret = pkt_get_track_info(pd, track, 1, &ti);
 	if (ret) {
-		pkt_err(pd, "failed get_track\n");
+		dev_err(ddev, "failed get_track\n");
 		return ret;
 	}
 
 	if (!pkt_writable_track(pd, &ti)) {
-		pkt_err(pd, "can't write to this track\n");
+		dev_err(ddev, "can't write to this track\n");
 		return -EROFS;
 	}
 
@@ -1797,11 +1835,11 @@ static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
 	 */
 	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
 	if (pd->settings.size == 0) {
-		pkt_notice(pd, "detected zero packet size!\n");
+		dev_notice(ddev, "detected zero packet size!\n");
 		return -ENXIO;
 	}
 	if (pd->settings.size > PACKET_MAX_SECTORS) {
-		pkt_err(pd, "packet size is too big\n");
+		dev_err(ddev, "packet size is too big\n");
 		return -EROFS;
 	}
 	pd->settings.fp = ti.fp;
@@ -1843,7 +1881,7 @@ static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
 			pd->settings.block_mode = PACKET_BLOCK_MODE2;
 			break;
 		default:
-			pkt_err(pd, "unknown data mode\n");
+			dev_err(ddev, "unknown data mode\n");
 			return -EROFS;
 	}
 	return 0;
@@ -1854,6 +1892,7 @@ static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
  */
 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_command cgc;
 	struct scsi_sense_hdr sshdr;
 	unsigned char buf[64];
@@ -1880,13 +1919,13 @@ static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd)
 	 */
 	buf[pd->mode_offset + 10] |= (set << 2);
 
-	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
+	cgc.buflen = cgc.cmd[8] = 2 + get_unaligned_be16(&buf[0]);
 	ret = pkt_mode_select(pd, &cgc);
 	if (ret) {
-		pkt_err(pd, "write caching control failed\n");
+		dev_err(ddev, "write caching control failed\n");
 		pkt_dump_sense(pd, &cgc);
 	} else if (!ret && set)
-		pkt_notice(pd, "enabled write caching\n");
+		dev_notice(ddev, "enabled write caching\n");
 	return ret;
 }
 
@@ -1935,12 +1974,12 @@ static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
 		 * Speed Performance Descriptor Block", use the information
 		 * in the first block. (contains the highest speed)
 		 */
-		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
+		int num_spdb = get_unaligned_be16(&cap_buf[30]);
 		if (num_spdb > 0)
 			offset = 34;
 	}
 
-	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
+	*write_speed = get_unaligned_be16(&cap_buf[offset]);
 	return 0;
 }
 
@@ -1967,6 +2006,7 @@ static char us_clv_to_speed[16] = {
 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
 						unsigned *speed)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_command cgc;
 	struct scsi_sense_hdr sshdr;
 	unsigned char buf[64];
@@ -1984,7 +2024,7 @@ static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
 		pkt_dump_sense(pd, &cgc);
 		return ret;
 	}
-	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
+	size = 2 + get_unaligned_be16(&buf[0]);
 	if (size > sizeof(buf))
 		size = sizeof(buf);
 
@@ -2001,11 +2041,11 @@ static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
 	}
 
 	if (!(buf[6] & 0x40)) {
-		pkt_notice(pd, "disc type is not CD-RW\n");
+		dev_notice(ddev, "disc type is not CD-RW\n");
 		return 1;
 	}
 	if (!(buf[6] & 0x4)) {
-		pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n");
+		dev_notice(ddev, "A1 values on media are not valid, maybe not CDRW?\n");
 		return 1;
 	}
 
@@ -2025,25 +2065,26 @@ static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
 			*speed = us_clv_to_speed[sp];
 			break;
 		default:
-			pkt_notice(pd, "unknown disc sub-type %d\n", st);
+			dev_notice(ddev, "unknown disc sub-type %d\n", st);
 			return 1;
 	}
 	if (*speed) {
-		pkt_info(pd, "maximum media speed: %d\n", *speed);
+		dev_info(ddev, "maximum media speed: %d\n", *speed);
 		return 0;
 	} else {
-		pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st);
+		dev_notice(ddev, "unknown speed %d for sub-type %d\n", sp, st);
 		return 1;
 	}
 }
 
 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct packet_command cgc;
 	struct scsi_sense_hdr sshdr;
 	int ret;
 
-	pkt_dbg(2, pd, "Performing OPC\n");
+	dev_dbg(ddev, "Performing OPC\n");
 
 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 	cgc.sshdr = &sshdr;
@@ -2058,18 +2099,19 @@ static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
 
 static int pkt_open_write(struct pktcdvd_device *pd)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	int ret;
 	unsigned int write_speed, media_write_speed, read_speed;
 
 	ret = pkt_probe_settings(pd);
 	if (ret) {
-		pkt_dbg(2, pd, "failed probe\n");
+		dev_dbg(ddev, "failed probe\n");
 		return ret;
 	}
 
 	ret = pkt_set_write_settings(pd);
 	if (ret) {
-		pkt_dbg(1, pd, "failed saving write settings\n");
+		dev_notice(ddev, "failed saving write settings\n");
 		return -EIO;
 	}
 
@@ -2082,30 +2124,29 @@ static int pkt_open_write(struct pktcdvd_device *pd)
 		case 0x13: /* DVD-RW */
 		case 0x1a: /* DVD+RW */
 		case 0x12: /* DVD-RAM */
-			pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed);
+			dev_notice(ddev, "write speed %ukB/s\n", write_speed);
 			break;
 		default:
 			ret = pkt_media_speed(pd, &media_write_speed);
 			if (ret)
 				media_write_speed = 16;
 			write_speed = min(write_speed, media_write_speed * 177);
-			pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176);
+			dev_notice(ddev, "write speed %ux\n", write_speed / 176);
 			break;
 	}
 	read_speed = write_speed;
 
 	ret = pkt_set_speed(pd, write_speed, read_speed);
 	if (ret) {
-		pkt_dbg(1, pd, "couldn't set write speed\n");
+		dev_notice(ddev, "couldn't set write speed\n");
 		return -EIO;
 	}
 	pd->write_speed = write_speed;
 	pd->read_speed = read_speed;
 
 	ret = pkt_perform_opc(pd);
-	if (ret) {
-		pkt_dbg(1, pd, "Optimum Power Calibration failed\n");
-	}
+	if (ret)
+		dev_notice(ddev, "Optimum Power Calibration failed\n");
 
 	return 0;
 }
@@ -2113,8 +2154,9 @@ static int pkt_open_write(struct pktcdvd_device *pd)
 /*
  * called at open time.
  */
-static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
+static int pkt_open_dev(struct pktcdvd_device *pd, bool write)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	int ret;
 	long lba;
 	struct request_queue *q;
@@ -2125,7 +2167,7 @@ static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
 	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
 	 * so open should not fail.
 	 */
-	bdev = blkdev_get_by_dev(pd->bdev->bd_dev, FMODE_READ | FMODE_EXCL, pd);
+	bdev = blkdev_get_by_dev(pd->bdev->bd_dev, BLK_OPEN_READ, pd, NULL);
 	if (IS_ERR(bdev)) {
 		ret = PTR_ERR(bdev);
 		goto out;
@@ -2133,7 +2175,7 @@ static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
 
 	ret = pkt_get_last_written(pd, &lba);
 	if (ret) {
-		pkt_err(pd, "pkt_get_last_written failed\n");
+		dev_err(ddev, "pkt_get_last_written failed\n");
 		goto out_putdev;
 	}
 
@@ -2162,17 +2204,17 @@ static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
 
 	if (write) {
 		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
-			pkt_err(pd, "not enough memory for buffers\n");
+			dev_err(ddev, "not enough memory for buffers\n");
 			ret = -ENOMEM;
 			goto out_putdev;
 		}
-		pkt_info(pd, "%lukB available on disc\n", lba << 1);
+		dev_info(ddev, "%lukB available on disc\n", lba << 1);
 	}
 
 	return 0;
 
 out_putdev:
-	blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
+	blkdev_put(bdev, pd);
 out:
 	return ret;
 }
@@ -2183,13 +2225,15 @@ out:
  */
 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
+
 	if (flush && pkt_flush_cache(pd))
-		pkt_dbg(1, pd, "not flushing cache\n");
+		dev_notice(ddev, "not flushing cache\n");
 
 	pkt_lock_door(pd, 0);
 
 	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
-	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
+	blkdev_put(pd->bdev, pd);
 
 	pkt_shrink_pktlist(pd);
 }
@@ -2203,14 +2247,14 @@ static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
 	return pkt_devs[dev_minor];
 }
 
-static int pkt_open(struct block_device *bdev, fmode_t mode)
+static int pkt_open(struct gendisk *disk, blk_mode_t mode)
 {
 	struct pktcdvd_device *pd = NULL;
 	int ret;
 
 	mutex_lock(&pktcdvd_mutex);
 	mutex_lock(&ctl_mutex);
-	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
+	pd = pkt_find_dev_from_minor(disk->first_minor);
 	if (!pd) {
 		ret = -ENODEV;
 		goto out;
@@ -2219,22 +2263,21 @@ static int pkt_open(struct block_device *bdev, fmode_t mode)
 
 	pd->refcnt++;
 	if (pd->refcnt > 1) {
-		if ((mode & FMODE_WRITE) &&
+		if ((mode & BLK_OPEN_WRITE) &&
 		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
 			ret = -EBUSY;
 			goto out_dec;
 		}
 	} else {
-		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
+		ret = pkt_open_dev(pd, mode & BLK_OPEN_WRITE);
 		if (ret)
 			goto out_dec;
 		/*
 		 * needed here as well, since ext2 (among others) may change
 		 * the blocksize at mount time
 		 */
-		set_blocksize(bdev, CD_FRAMESIZE);
+		set_blocksize(disk->part0, CD_FRAMESIZE);
 	}
-
 	mutex_unlock(&ctl_mutex);
 	mutex_unlock(&pktcdvd_mutex);
 	return 0;
@@ -2247,7 +2290,7 @@ out:
 	return ret;
 }
 
-static void pkt_close(struct gendisk *disk, fmode_t mode)
+static void pkt_release(struct gendisk *disk)
 {
 	struct pktcdvd_device *pd = disk->private_data;
 
@@ -2385,15 +2428,15 @@ static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
 static void pkt_submit_bio(struct bio *bio)
 {
 	struct pktcdvd_device *pd = bio->bi_bdev->bd_disk->queue->queuedata;
+	struct device *ddev = disk_to_dev(pd->disk);
 	struct bio *split;
 
 	bio = bio_split_to_limits(bio);
 	if (!bio)
 		return;
 
-	pkt_dbg(2, pd, "start = %6llx stop = %6llx\n",
-		(unsigned long long)bio->bi_iter.bi_sector,
-		(unsigned long long)bio_end_sector(bio));
+	dev_dbg(ddev, "start = %6llx stop = %6llx\n",
+		bio->bi_iter.bi_sector, bio_end_sector(bio));
 
 	/*
 	 * Clone READ bios so we can have our own bi_end_io callback.
@@ -2404,13 +2447,12 @@ static void pkt_submit_bio(struct bio *bio)
 	}
 
 	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
-		pkt_notice(pd, "WRITE for ro device (%llu)\n",
-			   (unsigned long long)bio->bi_iter.bi_sector);
+		dev_notice(ddev, "WRITE for ro device (%llu)\n", bio->bi_iter.bi_sector);
 		goto end_io;
 	}
 
 	if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
-		pkt_err(pd, "wrong bio size\n");
+		dev_err(ddev, "wrong bio size\n");
 		goto end_io;
 	}
 
@@ -2446,74 +2488,15 @@ static void pkt_init_queue(struct pktcdvd_device *pd)
 	q->queuedata = pd;
 }
 
-static int pkt_seq_show(struct seq_file *m, void *p)
-{
-	struct pktcdvd_device *pd = m->private;
-	char *msg;
-	int states[PACKET_NUM_STATES];
-
-	seq_printf(m, "Writer %s mapped to %pg:\n", pd->name, pd->bdev);
-
-	seq_printf(m, "\nSettings:\n");
-	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
-
-	if (pd->settings.write_type == 0)
-		msg = "Packet";
-	else
-		msg = "Unknown";
-	seq_printf(m, "\twrite type:\t\t%s\n", msg);
-
-	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
-	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
-
-	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
-
-	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
-		msg = "Mode 1";
-	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
-		msg = "Mode 2";
-	else
-		msg = "Unknown";
-	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
-
-	seq_printf(m, "\nStatistics:\n");
-	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
-	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
-	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
-	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
-	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
-
-	seq_printf(m, "\nMisc:\n");
-	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
-	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
-	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
-	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
-	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
-	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
-
-	seq_printf(m, "\nQueue state:\n");
-	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
-	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
-	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
-
-	pkt_count_states(pd, states);
-	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
-		   states[0], states[1], states[2], states[3], states[4], states[5]);
-
-	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
-			pd->write_congestion_off,
-			pd->write_congestion_on);
-	return 0;
-}
-
 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 {
+	struct device *ddev = disk_to_dev(pd->disk);
 	int i;
 	struct block_device *bdev;
 	struct scsi_device *sdev;
 
 	if (pd->pkt_dev == dev) {
-		pkt_err(pd, "recursive setup not allowed\n");
+		dev_err(ddev, "recursive setup not allowed\n");
 		return -EBUSY;
 	}
 	for (i = 0; i < MAX_WRITERS; i++) {
@@ -2521,21 +2504,22 @@ static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 		if (!pd2)
 			continue;
 		if (pd2->bdev->bd_dev == dev) {
-			pkt_err(pd, "%pg already setup\n", pd2->bdev);
+			dev_err(ddev, "%pg already setup\n", pd2->bdev);
 			return -EBUSY;
 		}
 		if (pd2->pkt_dev == dev) {
-			pkt_err(pd, "can't chain pktcdvd devices\n");
+			dev_err(ddev, "can't chain pktcdvd devices\n");
 			return -EBUSY;
 		}
 	}
 
-	bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_NDELAY, NULL);
+	bdev = blkdev_get_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_NDELAY, NULL,
+				 NULL);
 	if (IS_ERR(bdev))
 		return PTR_ERR(bdev);
 	sdev = scsi_device_from_queue(bdev->bd_disk->queue);
 	if (!sdev) {
-		blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
+		blkdev_put(bdev, NULL);
 		return -EINVAL;
 	}
 	put_device(&sdev->sdev_gendev);
@@ -2549,30 +2533,31 @@ static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 	pkt_init_queue(pd);
 
 	atomic_set(&pd->cdrw.pending_bios, 0);
-	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
+	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->disk->disk_name);
 	if (IS_ERR(pd->cdrw.thread)) {
-		pkt_err(pd, "can't start kernel thread\n");
+		dev_err(ddev, "can't start kernel thread\n");
 		goto out_mem;
 	}
 
-	proc_create_single_data(pd->name, 0, pkt_proc, pkt_seq_show, pd);
-	pkt_dbg(1, pd, "writer mapped to %pg\n", bdev);
+	proc_create_single_data(pd->disk->disk_name, 0, pkt_proc, pkt_seq_show, pd);
+	dev_notice(ddev, "writer mapped to %pg\n", bdev);
 	return 0;
 
 out_mem:
-	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
+	blkdev_put(bdev, NULL);
 	/* This is safe: open() is still holding a reference. */
 	module_put(THIS_MODULE);
 	return -ENOMEM;
 }
 
-static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
+static int pkt_ioctl(struct block_device *bdev, blk_mode_t mode,
+		unsigned int cmd, unsigned long arg)
 {
 	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
+	struct device *ddev = disk_to_dev(pd->disk);
 	int ret;
 
-	pkt_dbg(2, pd, "cmd %x, dev %d:%d\n",
-		cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
+	dev_dbg(ddev, "cmd %x, dev %d:%d\n", cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
 
 	mutex_lock(&pktcdvd_mutex);
 	switch (cmd) {
@@ -2598,7 +2583,7 @@ static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
 			ret = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
 		break;
 	default:
-		pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
+		dev_dbg(ddev, "Unknown ioctl (%x)\n", cmd);
 		ret = -ENOTTY;
 	}
 	mutex_unlock(&pktcdvd_mutex);
@@ -2631,7 +2616,7 @@ static const struct block_device_operations pktcdvd_ops = {
 	.owner =		THIS_MODULE,
 	.submit_bio =		pkt_submit_bio,
 	.open =			pkt_open,
-	.release =		pkt_close,
+	.release =		pkt_release,
 	.ioctl =		pkt_ioctl,
 	.compat_ioctl =		blkdev_compat_ptr_ioctl,
 	.check_events =		pkt_check_events,
@@ -2676,7 +2661,6 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 	spin_lock_init(&pd->iosched.lock);
 	bio_list_init(&pd->iosched.read_queue);
 	bio_list_init(&pd->iosched.write_queue);
-	sprintf(pd->name, DRIVER_NAME"%d", idx);
 	init_waitqueue_head(&pd->wqueue);
 	pd->bio_queue = RB_ROOT;
 
@@ -2693,7 +2677,7 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 	disk->minors = 1;
 	disk->fops = &pktcdvd_ops;
 	disk->flags = GENHD_FL_REMOVABLE | GENHD_FL_NO_PART;
-	strcpy(disk->disk_name, pd->name);
+	snprintf(disk->disk_name, sizeof(disk->disk_name), DRIVER_NAME"%d", idx);
 	disk->private_data = pd;
 
 	pd->pkt_dev = MKDEV(pktdev_major, idx);
@@ -2735,6 +2719,7 @@ out_mutex:
 static int pkt_remove_dev(dev_t pkt_dev)
 {
 	struct pktcdvd_device *pd;
+	struct device *ddev;
 	int idx;
 	int ret = 0;
 
@@ -2755,6 +2740,9 @@ static int pkt_remove_dev(dev_t pkt_dev)
 		ret = -EBUSY;
 		goto out;
 	}
+
+	ddev = disk_to_dev(pd->disk);
+
 	if (!IS_ERR(pd->cdrw.thread))
 		kthread_stop(pd->cdrw.thread);
 
@@ -2763,10 +2751,10 @@ static int pkt_remove_dev(dev_t pkt_dev)
 	pkt_debugfs_dev_remove(pd);
 	pkt_sysfs_dev_remove(pd);
 
-	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
+	blkdev_put(pd->bdev, NULL);
 
-	remove_proc_entry(pd->name, pkt_proc);
-	pkt_dbg(1, pd, "writer unmapped\n");
+	remove_proc_entry(pd->disk->disk_name, pkt_proc);
+	dev_notice(ddev, "writer unmapped\n");
 
 	del_gendisk(pd->disk);
 	put_disk(pd->disk);
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c
index 632751ddb287..bd0e075a5d89 100644
--- a/drivers/block/rbd.c
+++ b/drivers/block/rbd.c
@@ -660,9 +660,9 @@ static bool pending_result_dec(struct pending_result *pending, int *result)
 	return true;
 }
 
-static int rbd_open(struct block_device *bdev, fmode_t mode)
+static int rbd_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct rbd_device *rbd_dev = bdev->bd_disk->private_data;
+	struct rbd_device *rbd_dev = disk->private_data;
 	bool removing = false;
 
 	spin_lock_irq(&rbd_dev->lock);
@@ -679,7 +679,7 @@ static int rbd_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
-static void rbd_release(struct gendisk *disk, fmode_t mode)
+static void rbd_release(struct gendisk *disk)
 {
 	struct rbd_device *rbd_dev = disk->private_data;
 	unsigned long open_count_before;
diff --git a/drivers/block/rnbd/Makefile b/drivers/block/rnbd/Makefile
index 40b31630822c..208e5f865497 100644
--- a/drivers/block/rnbd/Makefile
+++ b/drivers/block/rnbd/Makefile
@@ -3,13 +3,11 @@
 ccflags-y := -I$(srctree)/drivers/infiniband/ulp/rtrs
 
 rnbd-client-y := rnbd-clt.o \
-		  rnbd-clt-sysfs.o \
-		  rnbd-common.o
+		  rnbd-clt-sysfs.o
 
 CFLAGS_rnbd-srv-trace.o = -I$(src)
 
-rnbd-server-y := rnbd-common.o \
-		  rnbd-srv.o \
+rnbd-server-y := rnbd-srv.o \
 		  rnbd-srv-sysfs.o \
 		  rnbd-srv-trace.o
 
diff --git a/drivers/block/rnbd/rnbd-clt-sysfs.c b/drivers/block/rnbd/rnbd-clt-sysfs.c
index 8c6087949794..c36d8b1ceeed 100644
--- a/drivers/block/rnbd/rnbd-clt-sysfs.c
+++ b/drivers/block/rnbd/rnbd-clt-sysfs.c
@@ -24,7 +24,9 @@
 #include "rnbd-clt.h"
 
 static struct device *rnbd_dev;
-static struct class *rnbd_dev_class;
+static const struct class rnbd_dev_class = {
+	.name = "rnbd_client",
+};
 static struct kobject *rnbd_devs_kobj;
 
 enum {
@@ -278,7 +280,7 @@ static ssize_t access_mode_show(struct kobject *kobj,
 
 	dev = container_of(kobj, struct rnbd_clt_dev, kobj);
 
-	return sysfs_emit(page, "%s\n", rnbd_access_mode_str(dev->access_mode));
+	return sysfs_emit(page, "%s\n", rnbd_access_modes[dev->access_mode].str);
 }
 
 static struct kobj_attribute rnbd_clt_access_mode =
@@ -596,7 +598,7 @@ static ssize_t rnbd_clt_map_device_store(struct kobject *kobj,
 
 	pr_info("Mapping device %s on session %s, (access_mode: %s, nr_poll_queues: %d)\n",
 		pathname, sessname,
-		rnbd_access_mode_str(access_mode),
+		rnbd_access_modes[access_mode].str,
 		nr_poll_queues);
 
 	dev = rnbd_clt_map_device(sessname, paths, path_cnt, port_nr, pathname,
@@ -646,11 +648,11 @@ int rnbd_clt_create_sysfs_files(void)
 {
 	int err;
 
-	rnbd_dev_class = class_create("rnbd-client");
-	if (IS_ERR(rnbd_dev_class))
-		return PTR_ERR(rnbd_dev_class);
+	err = class_register(&rnbd_dev_class);
+	if (err)
+		return err;
 
-	rnbd_dev = device_create_with_groups(rnbd_dev_class, NULL,
+	rnbd_dev = device_create_with_groups(&rnbd_dev_class, NULL,
 					      MKDEV(0, 0), NULL,
 					      default_attr_groups, "ctl");
 	if (IS_ERR(rnbd_dev)) {
@@ -666,9 +668,9 @@ int rnbd_clt_create_sysfs_files(void)
 	return 0;
 
 dev_destroy:
-	device_destroy(rnbd_dev_class, MKDEV(0, 0));
+	device_destroy(&rnbd_dev_class, MKDEV(0, 0));
 cls_destroy:
-	class_destroy(rnbd_dev_class);
+	class_unregister(&rnbd_dev_class);
 
 	return err;
 }
@@ -678,6 +680,6 @@ void rnbd_clt_destroy_sysfs_files(void)
 	sysfs_remove_group(&rnbd_dev->kobj, &default_attr_group);
 	kobject_del(rnbd_devs_kobj);
 	kobject_put(rnbd_devs_kobj);
-	device_destroy(rnbd_dev_class, MKDEV(0, 0));
-	class_destroy(rnbd_dev_class);
+	device_destroy(&rnbd_dev_class, MKDEV(0, 0));
+	class_unregister(&rnbd_dev_class);
 }
diff --git a/drivers/block/rnbd/rnbd-clt.c b/drivers/block/rnbd/rnbd-clt.c
index 5eb8c7855970..b0550b68645d 100644
--- a/drivers/block/rnbd/rnbd-clt.c
+++ b/drivers/block/rnbd/rnbd-clt.c
@@ -921,11 +921,11 @@ rnbd_clt_session *find_or_create_sess(const char *sessname, bool *first)
 	return sess;
 }
 
-static int rnbd_client_open(struct block_device *block_device, fmode_t mode)
+static int rnbd_client_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct rnbd_clt_dev *dev = block_device->bd_disk->private_data;
+	struct rnbd_clt_dev *dev = disk->private_data;
 
-	if (get_disk_ro(dev->gd) && (mode & FMODE_WRITE))
+	if (get_disk_ro(dev->gd) && (mode & BLK_OPEN_WRITE))
 		return -EPERM;
 
 	if (dev->dev_state == DEV_STATE_UNMAPPED ||
@@ -935,7 +935,7 @@ static int rnbd_client_open(struct block_device *block_device, fmode_t mode)
 	return 0;
 }
 
-static void rnbd_client_release(struct gendisk *gen, fmode_t mode)
+static void rnbd_client_release(struct gendisk *gen)
 {
 	struct rnbd_clt_dev *dev = gen->private_data;
 
diff --git a/drivers/block/rnbd/rnbd-common.c b/drivers/block/rnbd/rnbd-common.c
deleted file mode 100644
index 596c3f732403..000000000000
--- a/drivers/block/rnbd/rnbd-common.c
+++ /dev/null
@@ -1,23 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * RDMA Network Block Driver
- *
- * Copyright (c) 2014 - 2018 ProfitBricks GmbH. All rights reserved.
- * Copyright (c) 2018 - 2019 1&1 IONOS Cloud GmbH. All rights reserved.
- * Copyright (c) 2019 - 2020 1&1 IONOS SE. All rights reserved.
- */
-#include "rnbd-proto.h"
-
-const char *rnbd_access_mode_str(enum rnbd_access_mode mode)
-{
-	switch (mode) {
-	case RNBD_ACCESS_RO:
-		return "ro";
-	case RNBD_ACCESS_RW:
-		return "rw";
-	case RNBD_ACCESS_MIGRATION:
-		return "migration";
-	default:
-		return "unknown";
-	}
-}
diff --git a/drivers/block/rnbd/rnbd-proto.h b/drivers/block/rnbd/rnbd-proto.h
index da1d0542d7e2..e32f8f2c868a 100644
--- a/drivers/block/rnbd/rnbd-proto.h
+++ b/drivers/block/rnbd/rnbd-proto.h
@@ -61,6 +61,15 @@ enum rnbd_access_mode {
 	RNBD_ACCESS_MIGRATION,
 };
 
+static const __maybe_unused struct {
+	enum rnbd_access_mode mode;
+	const char *str;
+} rnbd_access_modes[] = {
+	[RNBD_ACCESS_RO] = {RNBD_ACCESS_RO, "ro"},
+	[RNBD_ACCESS_RW] = {RNBD_ACCESS_RW, "rw"},
+	[RNBD_ACCESS_MIGRATION] = {RNBD_ACCESS_MIGRATION, "migration"},
+};
+
 /**
  * struct rnbd_msg_sess_info - initial session info from client to server
  * @hdr:		message header
@@ -185,7 +194,6 @@ struct rnbd_msg_io {
 enum rnbd_io_flags {
 
 	/* Operations */
-
 	RNBD_OP_READ		= 0,
 	RNBD_OP_WRITE		= 1,
 	RNBD_OP_FLUSH		= 2,
@@ -193,15 +201,9 @@ enum rnbd_io_flags {
 	RNBD_OP_SECURE_ERASE	= 4,
 	RNBD_OP_WRITE_SAME	= 5,
 
-	RNBD_OP_LAST,
-
 	/* Flags */
-
 	RNBD_F_SYNC  = 1<<(RNBD_OP_BITS + 0),
 	RNBD_F_FUA   = 1<<(RNBD_OP_BITS + 1),
-
-	RNBD_F_ALL   = (RNBD_F_SYNC | RNBD_F_FUA)
-
 };
 
 static inline u32 rnbd_op(u32 flags)
@@ -214,21 +216,6 @@ static inline u32 rnbd_flags(u32 flags)
 	return flags & ~RNBD_OP_MASK;
 }
 
-static inline bool rnbd_flags_supported(u32 flags)
-{
-	u32 op;
-
-	op = rnbd_op(flags);
-	flags = rnbd_flags(flags);
-
-	if (op >= RNBD_OP_LAST)
-		return false;
-	if (flags & ~RNBD_F_ALL)
-		return false;
-
-	return true;
-}
-
 static inline blk_opf_t rnbd_to_bio_flags(u32 rnbd_opf)
 {
 	blk_opf_t bio_opf;
diff --git a/drivers/block/rnbd/rnbd-srv-sysfs.c b/drivers/block/rnbd/rnbd-srv-sysfs.c
index d5d9267e1fa5..cba6ba43c2c2 100644
--- a/drivers/block/rnbd/rnbd-srv-sysfs.c
+++ b/drivers/block/rnbd/rnbd-srv-sysfs.c
@@ -9,7 +9,6 @@
 #undef pr_fmt
 #define pr_fmt(fmt) KBUILD_MODNAME " L" __stringify(__LINE__) ": " fmt
 
-#include <uapi/linux/limits.h>
 #include <linux/kobject.h>
 #include <linux/sysfs.h>
 #include <linux/stat.h>
@@ -20,7 +19,9 @@
 #include "rnbd-srv.h"
 
 static struct device *rnbd_dev;
-static struct class *rnbd_dev_class;
+static const struct class rnbd_dev_class = {
+	.name = "rnbd-server",
+};
 static struct kobject *rnbd_devs_kobj;
 
 static void rnbd_srv_dev_release(struct kobject *kobj)
@@ -88,8 +89,7 @@ static ssize_t read_only_show(struct kobject *kobj, struct kobj_attribute *attr,
 
 	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
 
-	return sysfs_emit(page, "%d\n",
-			  !(sess_dev->open_flags & FMODE_WRITE));
+	return sysfs_emit(page, "%d\n", sess_dev->readonly);
 }
 
 static struct kobj_attribute rnbd_srv_dev_session_ro_attr =
@@ -104,7 +104,7 @@ static ssize_t access_mode_show(struct kobject *kobj,
 	sess_dev = container_of(kobj, struct rnbd_srv_sess_dev, kobj);
 
 	return sysfs_emit(page, "%s\n",
-			  rnbd_access_mode_str(sess_dev->access_mode));
+			  rnbd_access_modes[sess_dev->access_mode].str);
 }
 
 static struct kobj_attribute rnbd_srv_dev_session_access_mode_attr =
@@ -215,12 +215,12 @@ int rnbd_srv_create_sysfs_files(void)
 {
 	int err;
 
-	rnbd_dev_class = class_create("rnbd-server");
-	if (IS_ERR(rnbd_dev_class))
-		return PTR_ERR(rnbd_dev_class);
+	err = class_register(&rnbd_dev_class);
+	if (err)
+		return err;
 
-	rnbd_dev = device_create(rnbd_dev_class, NULL,
-				  MKDEV(0, 0), NULL, "ctl");
+	rnbd_dev = device_create(&rnbd_dev_class, NULL,
+				 MKDEV(0, 0), NULL, "ctl");
 	if (IS_ERR(rnbd_dev)) {
 		err = PTR_ERR(rnbd_dev);
 		goto cls_destroy;
@@ -234,9 +234,9 @@ int rnbd_srv_create_sysfs_files(void)
 	return 0;
 
 dev_destroy:
-	device_destroy(rnbd_dev_class, MKDEV(0, 0));
+	device_destroy(&rnbd_dev_class, MKDEV(0, 0));
 cls_destroy:
-	class_destroy(rnbd_dev_class);
+	class_unregister(&rnbd_dev_class);
 
 	return err;
 }
@@ -245,6 +245,6 @@ void rnbd_srv_destroy_sysfs_files(void)
 {
 	kobject_del(rnbd_devs_kobj);
 	kobject_put(rnbd_devs_kobj);
-	device_destroy(rnbd_dev_class, MKDEV(0, 0));
-	class_destroy(rnbd_dev_class);
+	device_destroy(&rnbd_dev_class, MKDEV(0, 0));
+	class_unregister(&rnbd_dev_class);
 }
diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index 2cfed2e58d64..c186df0ec641 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -96,7 +96,7 @@ rnbd_get_sess_dev(int dev_id, struct rnbd_srv_session *srv_sess)
 		ret = kref_get_unless_zero(&sess_dev->kref);
 	rcu_read_unlock();
 
-	if (!sess_dev || !ret)
+	if (!ret)
 		return ERR_PTR(-ENXIO);
 
 	return sess_dev;
@@ -180,7 +180,7 @@ static void destroy_device(struct kref *kref)
 
 	WARN_ONCE(!list_empty(&dev->sess_dev_list),
 		  "Device %s is being destroyed but still in use!\n",
-		  dev->id);
+		  dev->name);
 
 	spin_lock(&dev_lock);
 	list_del(&dev->list);
@@ -219,10 +219,10 @@ void rnbd_destroy_sess_dev(struct rnbd_srv_sess_dev *sess_dev, bool keep_id)
 	rnbd_put_sess_dev(sess_dev);
 	wait_for_completion(&dc); /* wait for inflights to drop to zero */
 
-	blkdev_put(sess_dev->bdev, sess_dev->open_flags);
+	blkdev_put(sess_dev->bdev, NULL);
 	mutex_lock(&sess_dev->dev->lock);
 	list_del(&sess_dev->dev_list);
-	if (sess_dev->open_flags & FMODE_WRITE)
+	if (!sess_dev->readonly)
 		sess_dev->dev->open_write_cnt--;
 	mutex_unlock(&sess_dev->dev->lock);
 
@@ -356,7 +356,7 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 			    const void *msg, size_t len,
 			    void *data, size_t datalen);
 
-static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
+static void process_msg_sess_info(struct rnbd_srv_session *srv_sess,
 				 const void *msg, size_t len,
 				 void *data, size_t datalen);
 
@@ -384,8 +384,7 @@ static int rnbd_srv_rdma_ev(void *priv, struct rtrs_srv_op *id,
 		ret = process_msg_open(srv_sess, usr, usrlen, data, datalen);
 		break;
 	case RNBD_MSG_SESS_INFO:
-		ret = process_msg_sess_info(srv_sess, usr, usrlen, data,
-					    datalen);
+		process_msg_sess_info(srv_sess, usr, usrlen, data, datalen);
 		break;
 	default:
 		pr_warn("Received unexpected message type %d from session %s\n",
@@ -431,7 +430,7 @@ static struct rnbd_srv_dev *rnbd_srv_init_srv_dev(struct block_device *bdev)
 	if (!dev)
 		return ERR_PTR(-ENOMEM);
 
-	snprintf(dev->id, sizeof(dev->id), "%pg", bdev);
+	snprintf(dev->name, sizeof(dev->name), "%pg", bdev);
 	kref_init(&dev->kref);
 	INIT_LIST_HEAD(&dev->sess_dev_list);
 	mutex_init(&dev->lock);
@@ -446,7 +445,7 @@ rnbd_srv_find_or_add_srv_dev(struct rnbd_srv_dev *new_dev)
 
 	spin_lock(&dev_lock);
 	list_for_each_entry(dev, &dev_list, list) {
-		if (!strncmp(dev->id, new_dev->id, sizeof(dev->id))) {
+		if (!strncmp(dev->name, new_dev->name, sizeof(dev->name))) {
 			if (!kref_get_unless_zero(&dev->kref))
 				/*
 				 * We lost the race, device is almost dead.
@@ -467,39 +466,38 @@ static int rnbd_srv_check_update_open_perm(struct rnbd_srv_dev *srv_dev,
 					    struct rnbd_srv_session *srv_sess,
 					    enum rnbd_access_mode access_mode)
 {
-	int ret = -EPERM;
+	int ret = 0;
 
 	mutex_lock(&srv_dev->lock);
 
 	switch (access_mode) {
 	case RNBD_ACCESS_RO:
-		ret = 0;
 		break;
 	case RNBD_ACCESS_RW:
 		if (srv_dev->open_write_cnt == 0)  {
 			srv_dev->open_write_cnt++;
-			ret = 0;
 		} else {
 			pr_err("Mapping device '%s' for session %s with RW permissions failed. Device already opened as 'RW' by %d client(s), access mode %s.\n",
-			       srv_dev->id, srv_sess->sessname,
+			       srv_dev->name, srv_sess->sessname,
 			       srv_dev->open_write_cnt,
-			       rnbd_access_mode_str(access_mode));
+			       rnbd_access_modes[access_mode].str);
+			ret = -EPERM;
 		}
 		break;
 	case RNBD_ACCESS_MIGRATION:
 		if (srv_dev->open_write_cnt < 2) {
 			srv_dev->open_write_cnt++;
-			ret = 0;
 		} else {
 			pr_err("Mapping device '%s' for session %s with migration permissions failed. Device already opened as 'RW' by %d client(s), access mode %s.\n",
-			       srv_dev->id, srv_sess->sessname,
+			       srv_dev->name, srv_sess->sessname,
 			       srv_dev->open_write_cnt,
-			       rnbd_access_mode_str(access_mode));
+			       rnbd_access_modes[access_mode].str);
+			ret = -EPERM;
 		}
 		break;
 	default:
 		pr_err("Received mapping request for device '%s' on session %s with invalid access mode: %d\n",
-		       srv_dev->id, srv_sess->sessname, access_mode);
+		       srv_dev->name, srv_sess->sessname, access_mode);
 		ret = -EINVAL;
 	}
 
@@ -561,7 +559,7 @@ static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp,
 static struct rnbd_srv_sess_dev *
 rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess,
 			      const struct rnbd_msg_open *open_msg,
-			      struct block_device *bdev, fmode_t open_flags,
+			      struct block_device *bdev, bool readonly,
 			      struct rnbd_srv_dev *srv_dev)
 {
 	struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess);
@@ -576,7 +574,7 @@ rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess,
 	sdev->bdev		= bdev;
 	sdev->sess		= srv_sess;
 	sdev->dev		= srv_dev;
-	sdev->open_flags	= open_flags;
+	sdev->readonly		= readonly;
 	sdev->access_mode	= open_msg->access_mode;
 
 	return sdev;
@@ -631,7 +629,7 @@ static char *rnbd_srv_get_full_path(struct rnbd_srv_session *srv_sess,
 	return full_path;
 }
 
-static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
+static void process_msg_sess_info(struct rnbd_srv_session *srv_sess,
 				 const void *msg, size_t len,
 				 void *data, size_t datalen)
 {
@@ -644,8 +642,6 @@ static int process_msg_sess_info(struct rnbd_srv_session *srv_sess,
 
 	rsp->hdr.type = cpu_to_le16(RNBD_MSG_SESS_INFO_RSP);
 	rsp->ver = srv_sess->ver;
-
-	return 0;
 }
 
 /**
@@ -681,15 +677,14 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 	struct rnbd_srv_sess_dev *srv_sess_dev;
 	const struct rnbd_msg_open *open_msg = msg;
 	struct block_device *bdev;
-	fmode_t open_flags;
+	blk_mode_t open_flags = BLK_OPEN_READ;
 	char *full_path;
 	struct rnbd_msg_open_rsp *rsp = data;
 
 	trace_process_msg_open(srv_sess, open_msg);
 
-	open_flags = FMODE_READ;
 	if (open_msg->access_mode != RNBD_ACCESS_RO)
-		open_flags |= FMODE_WRITE;
+		open_flags |= BLK_OPEN_WRITE;
 
 	mutex_lock(&srv_sess->lock);
 
@@ -719,7 +714,7 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 		goto reject;
 	}
 
-	bdev = blkdev_get_by_path(full_path, open_flags, THIS_MODULE);
+	bdev = blkdev_get_by_path(full_path, open_flags, NULL, NULL);
 	if (IS_ERR(bdev)) {
 		ret = PTR_ERR(bdev);
 		pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %d\n",
@@ -736,9 +731,9 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 		goto blkdev_put;
 	}
 
-	srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg,
-						     bdev, open_flags,
-						     srv_dev);
+	srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg, bdev,
+				open_msg->access_mode == RNBD_ACCESS_RO,
+				srv_dev);
 	if (IS_ERR(srv_sess_dev)) {
 		pr_err("Opening device '%s' on session %s failed, creating sess_dev failed, err: %ld\n",
 		       full_path, srv_sess->sessname, PTR_ERR(srv_sess_dev));
@@ -774,7 +769,7 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 	list_add(&srv_sess_dev->dev_list, &srv_dev->sess_dev_list);
 	mutex_unlock(&srv_dev->lock);
 
-	rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->id);
+	rnbd_srv_info(srv_sess_dev, "Opened device '%s'\n", srv_dev->name);
 
 	kfree(full_path);
 
@@ -795,7 +790,7 @@ srv_dev_put:
 	}
 	rnbd_put_srv_dev(srv_dev);
 blkdev_put:
-	blkdev_put(bdev, open_flags);
+	blkdev_put(bdev, NULL);
 free_path:
 	kfree(full_path);
 reject:
@@ -808,7 +803,7 @@ static struct rtrs_srv_ctx *rtrs_ctx;
 static struct rtrs_srv_ops rtrs_ops;
 static int __init rnbd_srv_init_module(void)
 {
-	int err;
+	int err = 0;
 
 	BUILD_BUG_ON(sizeof(struct rnbd_msg_hdr) != 4);
 	BUILD_BUG_ON(sizeof(struct rnbd_msg_sess_info) != 36);
@@ -822,19 +817,17 @@ static int __init rnbd_srv_init_module(void)
 	};
 	rtrs_ctx = rtrs_srv_open(&rtrs_ops, port_nr);
 	if (IS_ERR(rtrs_ctx)) {
-		err = PTR_ERR(rtrs_ctx);
 		pr_err("rtrs_srv_open(), err: %d\n", err);
-		return err;
+		return PTR_ERR(rtrs_ctx);
 	}
 
 	err = rnbd_srv_create_sysfs_files();
 	if (err) {
 		pr_err("rnbd_srv_create_sysfs_files(), err: %d\n", err);
 		rtrs_srv_close(rtrs_ctx);
-		return err;
 	}
 
-	return 0;
+	return err;
 }
 
 static void __exit rnbd_srv_cleanup_module(void)
diff --git a/drivers/block/rnbd/rnbd-srv.h b/drivers/block/rnbd/rnbd-srv.h
index f5962fd31d62..1027656dedb0 100644
--- a/drivers/block/rnbd/rnbd-srv.h
+++ b/drivers/block/rnbd/rnbd-srv.h
@@ -35,7 +35,7 @@ struct rnbd_srv_dev {
 	struct kobject                  dev_kobj;
 	struct kobject                  *dev_sessions_kobj;
 	struct kref                     kref;
-	char				id[NAME_MAX];
+	char				name[NAME_MAX];
 	/* List of rnbd_srv_sess_dev structs */
 	struct list_head		sess_dev_list;
 	struct mutex			lock;
@@ -52,7 +52,7 @@ struct rnbd_srv_sess_dev {
 	struct kobject                  kobj;
 	u32                             device_id;
 	bool				keep_id;
-	fmode_t                         open_flags;
+	bool				readonly;
 	struct kref			kref;
 	struct completion               *destroy_comp;
 	char				pathname[NAME_MAX];
diff --git a/drivers/block/sunvdc.c b/drivers/block/sunvdc.c
index 9fa821fa76b0..7bf4b48e2282 100644
--- a/drivers/block/sunvdc.c
+++ b/drivers/block/sunvdc.c
@@ -139,7 +139,7 @@ static int vdc_getgeo(struct block_device *bdev, struct hd_geometry *geo)
  * when vdisk_mtype is VD_MEDIA_TYPE_CD or VD_MEDIA_TYPE_DVD.
  * Needed to be able to install inside an ldom from an iso image.
  */
-static int vdc_ioctl(struct block_device *bdev, fmode_t mode,
+static int vdc_ioctl(struct block_device *bdev, blk_mode_t mode,
 		     unsigned command, unsigned long argument)
 {
 	struct vdc_port *port = bdev->bd_disk->private_data;
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index 42b4b6828690..f85b6af414b4 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -608,20 +608,18 @@ static void setup_medium(struct floppy_state *fs)
 	}
 }
 
-static int floppy_open(struct block_device *bdev, fmode_t mode)
+static int floppy_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct floppy_state *fs = bdev->bd_disk->private_data;
+	struct floppy_state *fs = disk->private_data;
 	struct swim __iomem *base = fs->swd->base;
 	int err;
 
-	if (fs->ref_count == -1 || (fs->ref_count && mode & FMODE_EXCL))
+	if (fs->ref_count == -1 || (fs->ref_count && mode & BLK_OPEN_EXCL))
 		return -EBUSY;
-
-	if (mode & FMODE_EXCL)
+	if (mode & BLK_OPEN_EXCL)
 		fs->ref_count = -1;
 	else
 		fs->ref_count++;
-
 	swim_write(base, setup, S_IBM_DRIVE  | S_FCLK_DIV2);
 	udelay(10);
 	swim_drive(base, fs->location);
@@ -636,13 +634,13 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 
 	set_capacity(fs->disk, fs->total_secs);
 
-	if (mode & FMODE_NDELAY)
+	if (mode & BLK_OPEN_NDELAY)
 		return 0;
 
-	if (mode & (FMODE_READ|FMODE_WRITE)) {
-		if (bdev_check_media_change(bdev) && fs->disk_in)
+	if (mode & (BLK_OPEN_READ | BLK_OPEN_WRITE)) {
+		if (disk_check_media_change(disk) && fs->disk_in)
 			fs->ejected = 0;
-		if ((mode & FMODE_WRITE) && fs->write_protected) {
+		if ((mode & BLK_OPEN_WRITE) && fs->write_protected) {
 			err = -EROFS;
 			goto out;
 		}
@@ -659,18 +657,18 @@ out:
 	return err;
 }
 
-static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+static int floppy_unlocked_open(struct gendisk *disk, blk_mode_t mode)
 {
 	int ret;
 
 	mutex_lock(&swim_mutex);
-	ret = floppy_open(bdev, mode);
+	ret = floppy_open(disk, mode);
 	mutex_unlock(&swim_mutex);
 
 	return ret;
 }
 
-static void floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk)
 {
 	struct floppy_state *fs = disk->private_data;
 	struct swim __iomem *base = fs->swd->base;
@@ -686,7 +684,7 @@ static void floppy_release(struct gendisk *disk, fmode_t mode)
 	mutex_unlock(&swim_mutex);
 }
 
-static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
+static int floppy_ioctl(struct block_device *bdev, blk_mode_t mode,
 			unsigned int cmd, unsigned long param)
 {
 	struct floppy_state *fs = bdev->bd_disk->private_data;
diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
index da811a7da03f..dc43a63b3469 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -246,10 +246,9 @@ static int grab_drive(struct floppy_state *fs, enum swim_state state,
 		      int interruptible);
 static void release_drive(struct floppy_state *fs);
 static int fd_eject(struct floppy_state *fs);
-static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
+static int floppy_ioctl(struct block_device *bdev, blk_mode_t mode,
 			unsigned int cmd, unsigned long param);
-static int floppy_open(struct block_device *bdev, fmode_t mode);
-static void floppy_release(struct gendisk *disk, fmode_t mode);
+static int floppy_open(struct gendisk *disk, blk_mode_t mode);
 static unsigned int floppy_check_events(struct gendisk *disk,
 					unsigned int clearing);
 static int floppy_revalidate(struct gendisk *disk);
@@ -883,7 +882,7 @@ static int fd_eject(struct floppy_state *fs)
 static struct floppy_struct floppy_type =
 	{ 2880,18,2,80,0,0x1B,0x00,0xCF,0x6C,NULL };	/*  7 1.44MB 3.5"   */
 
-static int floppy_locked_ioctl(struct block_device *bdev, fmode_t mode,
+static int floppy_locked_ioctl(struct block_device *bdev, blk_mode_t mode,
 			unsigned int cmd, unsigned long param)
 {
 	struct floppy_state *fs = bdev->bd_disk->private_data;
@@ -911,7 +910,7 @@ static int floppy_locked_ioctl(struct block_device *bdev, fmode_t mode,
 	return -ENOTTY;
 }
 
-static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
+static int floppy_ioctl(struct block_device *bdev, blk_mode_t mode,
 				 unsigned int cmd, unsigned long param)
 {
 	int ret;
@@ -923,9 +922,9 @@ static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
 	return ret;
 }
 
-static int floppy_open(struct block_device *bdev, fmode_t mode)
+static int floppy_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct floppy_state *fs = bdev->bd_disk->private_data;
+	struct floppy_state *fs = disk->private_data;
 	struct swim3 __iomem *sw = fs->swim3;
 	int n, err = 0;
 
@@ -958,18 +957,18 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 		swim3_action(fs, SETMFM);
 		swim3_select(fs, RELAX);
 
-	} else if (fs->ref_count == -1 || mode & FMODE_EXCL)
+	} else if (fs->ref_count == -1 || mode & BLK_OPEN_EXCL)
 		return -EBUSY;
 
-	if (err == 0 && (mode & FMODE_NDELAY) == 0
-	    && (mode & (FMODE_READ|FMODE_WRITE))) {
-		if (bdev_check_media_change(bdev))
-			floppy_revalidate(bdev->bd_disk);
+	if (err == 0 && !(mode & BLK_OPEN_NDELAY) &&
+	    (mode & (BLK_OPEN_READ | BLK_OPEN_WRITE))) {
+		if (disk_check_media_change(disk))
+			floppy_revalidate(disk);
 		if (fs->ejected)
 			err = -ENXIO;
 	}
 
-	if (err == 0 && (mode & FMODE_WRITE)) {
+	if (err == 0 && (mode & BLK_OPEN_WRITE)) {
 		if (fs->write_prot < 0)
 			fs->write_prot = swim3_readbit(fs, WRITE_PROT);
 		if (fs->write_prot)
@@ -985,7 +984,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 		return err;
 	}
 
-	if (mode & FMODE_EXCL)
+	if (mode & BLK_OPEN_EXCL)
 		fs->ref_count = -1;
 	else
 		++fs->ref_count;
@@ -993,18 +992,18 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
-static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+static int floppy_unlocked_open(struct gendisk *disk, blk_mode_t mode)
 {
 	int ret;
 
 	mutex_lock(&swim3_mutex);
-	ret = floppy_open(bdev, mode);
+	ret = floppy_open(disk, mode);
 	mutex_unlock(&swim3_mutex);
 
 	return ret;
 }
 
-static void floppy_release(struct gendisk *disk, fmode_t mode)
+static void floppy_release(struct gendisk *disk)
 {
 	struct floppy_state *fs = disk->private_data;
 	struct swim3 __iomem *sw = fs->swim3;
diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index 33d3298a0da1..1c823750c95a 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -43,6 +43,7 @@
 #include <asm/page.h>
 #include <linux/task_work.h>
 #include <linux/namei.h>
+#include <linux/kref.h>
 #include <uapi/linux/ublk_cmd.h>
 
 #define UBLK_MINORS		(1U << MINORBITS)
@@ -54,7 +55,8 @@
 		| UBLK_F_USER_RECOVERY \
 		| UBLK_F_USER_RECOVERY_REISSUE \
 		| UBLK_F_UNPRIVILEGED_DEV \
-		| UBLK_F_CMD_IOCTL_ENCODE)
+		| UBLK_F_CMD_IOCTL_ENCODE \
+		| UBLK_F_USER_COPY)
 
 /* All UBLK_PARAM_TYPE_* should be included here */
 #define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | \
@@ -62,7 +64,8 @@
 
 struct ublk_rq_data {
 	struct llist_node node;
-	struct callback_head work;
+
+	struct kref ref;
 };
 
 struct ublk_uring_cmd_pdu {
@@ -182,8 +185,13 @@ struct ublk_params_header {
 	__u32	types;
 };
 
+static inline void __ublk_complete_rq(struct request *req);
+static void ublk_complete_rq(struct kref *ref);
+
 static dev_t ublk_chr_devt;
-static struct class *ublk_chr_class;
+static const struct class ublk_chr_class = {
+	.name = "ublk-char",
+};
 
 static DEFINE_IDR(ublk_index_idr);
 static DEFINE_SPINLOCK(ublk_idr_lock);
@@ -202,6 +210,23 @@ static unsigned int ublks_added;	/* protected by ublk_ctl_mutex */
 
 static struct miscdevice ublk_misc;
 
+static inline unsigned ublk_pos_to_hwq(loff_t pos)
+{
+	return ((pos - UBLKSRV_IO_BUF_OFFSET) >> UBLK_QID_OFF) &
+		UBLK_QID_BITS_MASK;
+}
+
+static inline unsigned ublk_pos_to_buf_off(loff_t pos)
+{
+	return (pos - UBLKSRV_IO_BUF_OFFSET) & UBLK_IO_BUF_BITS_MASK;
+}
+
+static inline unsigned ublk_pos_to_tag(loff_t pos)
+{
+	return ((pos - UBLKSRV_IO_BUF_OFFSET) >> UBLK_TAG_OFF) &
+		UBLK_TAG_BITS_MASK;
+}
+
 static void ublk_dev_param_basic_apply(struct ublk_device *ub)
 {
 	struct request_queue *q = ub->ub_disk->queue;
@@ -290,12 +315,52 @@ static int ublk_apply_params(struct ublk_device *ub)
 	return 0;
 }
 
-static inline bool ublk_can_use_task_work(const struct ublk_queue *ubq)
+static inline bool ublk_support_user_copy(const struct ublk_queue *ubq)
 {
-	if (IS_BUILTIN(CONFIG_BLK_DEV_UBLK) &&
-			!(ubq->flags & UBLK_F_URING_CMD_COMP_IN_TASK))
-		return true;
-	return false;
+	return ubq->flags & UBLK_F_USER_COPY;
+}
+
+static inline bool ublk_need_req_ref(const struct ublk_queue *ubq)
+{
+	/*
+	 * read()/write() is involved in user copy, so request reference
+	 * has to be grabbed
+	 */
+	return ublk_support_user_copy(ubq);
+}
+
+static inline void ublk_init_req_ref(const struct ublk_queue *ubq,
+		struct request *req)
+{
+	if (ublk_need_req_ref(ubq)) {
+		struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
+
+		kref_init(&data->ref);
+	}
+}
+
+static inline bool ublk_get_req_ref(const struct ublk_queue *ubq,
+		struct request *req)
+{
+	if (ublk_need_req_ref(ubq)) {
+		struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
+
+		return kref_get_unless_zero(&data->ref);
+	}
+
+	return true;
+}
+
+static inline void ublk_put_req_ref(const struct ublk_queue *ubq,
+		struct request *req)
+{
+	if (ublk_need_req_ref(ubq)) {
+		struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
+
+		kref_put(&data->ref, ublk_complete_rq);
+	} else {
+		__ublk_complete_rq(req);
+	}
 }
 
 static inline bool ublk_need_get_data(const struct ublk_queue *ubq)
@@ -384,9 +449,9 @@ static void ublk_store_owner_uid_gid(unsigned int *owner_uid,
 	*owner_gid = from_kgid(&init_user_ns, gid);
 }
 
-static int ublk_open(struct block_device *bdev, fmode_t mode)
+static int ublk_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct ublk_device *ub = bdev->bd_disk->private_data;
+	struct ublk_device *ub = disk->private_data;
 
 	if (capable(CAP_SYS_ADMIN))
 		return 0;
@@ -421,49 +486,39 @@ static const struct block_device_operations ub_fops = {
 
 #define UBLK_MAX_PIN_PAGES	32
 
-struct ublk_map_data {
-	const struct request *rq;
-	unsigned long	ubuf;
-	unsigned int	len;
-};
-
 struct ublk_io_iter {
 	struct page *pages[UBLK_MAX_PIN_PAGES];
-	unsigned pg_off;	/* offset in the 1st page in pages */
-	int nr_pages;		/* how many page pointers in pages */
 	struct bio *bio;
 	struct bvec_iter iter;
 };
 
-static inline unsigned ublk_copy_io_pages(struct ublk_io_iter *data,
-		unsigned max_bytes, bool to_vm)
+/* return how many pages are copied */
+static void ublk_copy_io_pages(struct ublk_io_iter *data,
+		size_t total, size_t pg_off, int dir)
 {
-	const unsigned total = min_t(unsigned, max_bytes,
-			PAGE_SIZE - data->pg_off +
-			((data->nr_pages - 1) << PAGE_SHIFT));
 	unsigned done = 0;
 	unsigned pg_idx = 0;
 
 	while (done < total) {
 		struct bio_vec bv = bio_iter_iovec(data->bio, data->iter);
-		const unsigned int bytes = min3(bv.bv_len, total - done,
-				(unsigned)(PAGE_SIZE - data->pg_off));
+		unsigned int bytes = min3(bv.bv_len, (unsigned)total - done,
+				(unsigned)(PAGE_SIZE - pg_off));
 		void *bv_buf = bvec_kmap_local(&bv);
 		void *pg_buf = kmap_local_page(data->pages[pg_idx]);
 
-		if (to_vm)
-			memcpy(pg_buf + data->pg_off, bv_buf, bytes);
+		if (dir == ITER_DEST)
+			memcpy(pg_buf + pg_off, bv_buf, bytes);
 		else
-			memcpy(bv_buf, pg_buf + data->pg_off, bytes);
+			memcpy(bv_buf, pg_buf + pg_off, bytes);
 
 		kunmap_local(pg_buf);
 		kunmap_local(bv_buf);
 
 		/* advance page array */
-		data->pg_off += bytes;
-		if (data->pg_off == PAGE_SIZE) {
+		pg_off += bytes;
+		if (pg_off == PAGE_SIZE) {
 			pg_idx += 1;
-			data->pg_off = 0;
+			pg_off = 0;
 		}
 
 		done += bytes;
@@ -477,41 +532,58 @@ static inline unsigned ublk_copy_io_pages(struct ublk_io_iter *data,
 			data->iter = data->bio->bi_iter;
 		}
 	}
+}
 
-	return done;
+static bool ublk_advance_io_iter(const struct request *req,
+		struct ublk_io_iter *iter, unsigned int offset)
+{
+	struct bio *bio = req->bio;
+
+	for_each_bio(bio) {
+		if (bio->bi_iter.bi_size > offset) {
+			iter->bio = bio;
+			iter->iter = bio->bi_iter;
+			bio_advance_iter(iter->bio, &iter->iter, offset);
+			return true;
+		}
+		offset -= bio->bi_iter.bi_size;
+	}
+	return false;
 }
 
-static int ublk_copy_user_pages(struct ublk_map_data *data, bool to_vm)
+/*
+ * Copy data between request pages and io_iter, and 'offset'
+ * is the start point of linear offset of request.
+ */
+static size_t ublk_copy_user_pages(const struct request *req,
+		unsigned offset, struct iov_iter *uiter, int dir)
 {
-	const unsigned int gup_flags = to_vm ? FOLL_WRITE : 0;
-	const unsigned long start_vm = data->ubuf;
-	unsigned int done = 0;
-	struct ublk_io_iter iter = {
-		.pg_off	= start_vm & (PAGE_SIZE - 1),
-		.bio	= data->rq->bio,
-		.iter	= data->rq->bio->bi_iter,
-	};
-	const unsigned int nr_pages = round_up(data->len +
-			(start_vm & (PAGE_SIZE - 1)), PAGE_SIZE) >> PAGE_SHIFT;
-
-	while (done < nr_pages) {
-		const unsigned to_pin = min_t(unsigned, UBLK_MAX_PIN_PAGES,
-				nr_pages - done);
-		unsigned i, len;
-
-		iter.nr_pages = get_user_pages_fast(start_vm +
-				(done << PAGE_SHIFT), to_pin, gup_flags,
-				iter.pages);
-		if (iter.nr_pages <= 0)
-			return done == 0 ? iter.nr_pages : done;
-		len = ublk_copy_io_pages(&iter, data->len, to_vm);
-		for (i = 0; i < iter.nr_pages; i++) {
-			if (to_vm)
+	struct ublk_io_iter iter;
+	size_t done = 0;
+
+	if (!ublk_advance_io_iter(req, &iter, offset))
+		return 0;
+
+	while (iov_iter_count(uiter) && iter.bio) {
+		unsigned nr_pages;
+		ssize_t len;
+		size_t off;
+		int i;
+
+		len = iov_iter_get_pages2(uiter, iter.pages,
+				iov_iter_count(uiter),
+				UBLK_MAX_PIN_PAGES, &off);
+		if (len <= 0)
+			return done;
+
+		ublk_copy_io_pages(&iter, len, off, dir);
+		nr_pages = DIV_ROUND_UP(len + off, PAGE_SIZE);
+		for (i = 0; i < nr_pages; i++) {
+			if (dir == ITER_DEST)
 				set_page_dirty(iter.pages[i]);
 			put_page(iter.pages[i]);
 		}
-		data->len -= len;
-		done += iter.nr_pages;
+		done += len;
 	}
 
 	return done;
@@ -532,21 +604,23 @@ static int ublk_map_io(const struct ublk_queue *ubq, const struct request *req,
 {
 	const unsigned int rq_bytes = blk_rq_bytes(req);
 
+	if (ublk_support_user_copy(ubq))
+		return rq_bytes;
+
 	/*
 	 * no zero copy, we delay copy WRITE request data into ublksrv
 	 * context and the big benefit is that pinning pages in current
 	 * context is pretty fast, see ublk_pin_user_pages
 	 */
 	if (ublk_need_map_req(req)) {
-		struct ublk_map_data data = {
-			.rq	=	req,
-			.ubuf	=	io->addr,
-			.len	=	rq_bytes,
-		};
+		struct iov_iter iter;
+		struct iovec iov;
+		const int dir = ITER_DEST;
 
-		ublk_copy_user_pages(&data, true);
+		import_single_range(dir, u64_to_user_ptr(io->addr), rq_bytes,
+				&iov, &iter);
 
-		return rq_bytes - data.len;
+		return ublk_copy_user_pages(req, 0, &iter, dir);
 	}
 	return rq_bytes;
 }
@@ -557,18 +631,19 @@ static int ublk_unmap_io(const struct ublk_queue *ubq,
 {
 	const unsigned int rq_bytes = blk_rq_bytes(req);
 
+	if (ublk_support_user_copy(ubq))
+		return rq_bytes;
+
 	if (ublk_need_unmap_req(req)) {
-		struct ublk_map_data data = {
-			.rq	=	req,
-			.ubuf	=	io->addr,
-			.len	=	io->res,
-		};
+		struct iov_iter iter;
+		struct iovec iov;
+		const int dir = ITER_SOURCE;
 
 		WARN_ON_ONCE(io->res > rq_bytes);
 
-		ublk_copy_user_pages(&data, false);
-
-		return io->res - data.len;
+		import_single_range(dir, u64_to_user_ptr(io->addr), io->res,
+				&iov, &iter);
+		return ublk_copy_user_pages(req, 0, &iter, dir);
 	}
 	return rq_bytes;
 }
@@ -648,13 +723,19 @@ static inline bool ubq_daemon_is_dying(struct ublk_queue *ubq)
 }
 
 /* todo: handle partial completion */
-static void ublk_complete_rq(struct request *req)
+static inline void __ublk_complete_rq(struct request *req)
 {
 	struct ublk_queue *ubq = req->mq_hctx->driver_data;
 	struct ublk_io *io = &ubq->ios[req->tag];
 	unsigned int unmapped_bytes;
 	blk_status_t res = BLK_STS_OK;
 
+	/* called from ublk_abort_queue() code path */
+	if (io->flags & UBLK_IO_FLAG_ABORTED) {
+		res = BLK_STS_IOERR;
+		goto exit;
+	}
+
 	/* failed read IO if nothing is read */
 	if (!io->res && req_op(req) == REQ_OP_READ)
 		io->res = -EIO;
@@ -694,6 +775,15 @@ exit:
 	blk_mq_end_request(req, res);
 }
 
+static void ublk_complete_rq(struct kref *ref)
+{
+	struct ublk_rq_data *data = container_of(ref, struct ublk_rq_data,
+			ref);
+	struct request *req = blk_mq_rq_from_pdu(data);
+
+	__ublk_complete_rq(req);
+}
+
 /*
  * Since __ublk_rq_task_work always fails requests immediately during
  * exiting, __ublk_fail_req() is only called from abort context during
@@ -712,7 +802,7 @@ static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io,
 		if (ublk_queue_can_use_recovery_reissue(ubq))
 			blk_mq_requeue_request(req, false);
 		else
-			blk_mq_end_request(req, BLK_STS_IOERR);
+			ublk_put_req_ref(ubq, req);
 	}
 }
 
@@ -821,6 +911,7 @@ static inline void __ublk_rq_task_work(struct request *req,
 			mapped_bytes >> 9;
 	}
 
+	ublk_init_req_ref(ubq, req);
 	ubq_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags);
 }
 
@@ -852,17 +943,6 @@ static void ublk_rq_task_work_cb(struct io_uring_cmd *cmd, unsigned issue_flags)
 	ublk_forward_io_cmds(ubq, issue_flags);
 }
 
-static void ublk_rq_task_work_fn(struct callback_head *work)
-{
-	struct ublk_rq_data *data = container_of(work,
-			struct ublk_rq_data, work);
-	struct request *req = blk_mq_rq_from_pdu(data);
-	struct ublk_queue *ubq = req->mq_hctx->driver_data;
-	unsigned issue_flags = IO_URING_F_UNLOCKED;
-
-	ublk_forward_io_cmds(ubq, issue_flags);
-}
-
 static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
 {
 	struct ublk_rq_data *data = blk_mq_rq_to_pdu(rq);
@@ -886,10 +966,6 @@ static void ublk_queue_cmd(struct ublk_queue *ubq, struct request *rq)
 	 */
 	if (unlikely(io->flags & UBLK_IO_FLAG_ABORTED)) {
 		ublk_abort_io_cmds(ubq);
-	} else if (ublk_can_use_task_work(ubq)) {
-		if (task_work_add(ubq->ubq_daemon, &data->work,
-					TWA_SIGNAL_NO_IPI))
-			ublk_abort_io_cmds(ubq);
 	} else {
 		struct io_uring_cmd *cmd = io->cmd;
 		struct ublk_uring_cmd_pdu *pdu = ublk_get_uring_cmd_pdu(cmd);
@@ -961,19 +1037,9 @@ static int ublk_init_hctx(struct blk_mq_hw_ctx *hctx, void *driver_data,
 	return 0;
 }
 
-static int ublk_init_rq(struct blk_mq_tag_set *set, struct request *req,
-		unsigned int hctx_idx, unsigned int numa_node)
-{
-	struct ublk_rq_data *data = blk_mq_rq_to_pdu(req);
-
-	init_task_work(&data->work, ublk_rq_task_work_fn);
-	return 0;
-}
-
 static const struct blk_mq_ops ublk_mq_ops = {
 	.queue_rq       = ublk_queue_rq,
 	.init_hctx	= ublk_init_hctx,
-	.init_request   = ublk_init_rq,
 	.timeout	= ublk_timeout,
 };
 
@@ -1050,7 +1116,7 @@ static void ublk_commit_completion(struct ublk_device *ub,
 	req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag);
 
 	if (req && likely(!blk_should_fake_timeout(req->q)))
-		ublk_complete_rq(req);
+		ublk_put_req_ref(ubq, req);
 }
 
 /*
@@ -1295,6 +1361,14 @@ static inline int ublk_check_cmd_op(u32 cmd_op)
 	return 0;
 }
 
+static inline void ublk_fill_io_cmd(struct ublk_io *io,
+		struct io_uring_cmd *cmd, unsigned long buf_addr)
+{
+	io->cmd = cmd;
+	io->flags |= UBLK_IO_FLAG_ACTIVE;
+	io->addr = buf_addr;
+}
+
 static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 			       unsigned int issue_flags,
 			       const struct ublksrv_io_cmd *ub_cmd)
@@ -1340,6 +1414,11 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 			^ (_IOC_NR(cmd_op) == UBLK_IO_NEED_GET_DATA))
 		goto out;
 
+	if (ublk_support_user_copy(ubq) && ub_cmd->addr) {
+		ret = -EINVAL;
+		goto out;
+	}
+
 	ret = ublk_check_cmd_op(cmd_op);
 	if (ret)
 		goto out;
@@ -1358,36 +1437,41 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 		 */
 		if (io->flags & UBLK_IO_FLAG_OWNED_BY_SRV)
 			goto out;
-		/* FETCH_RQ has to provide IO buffer if NEED GET DATA is not enabled */
-		if (!ub_cmd->addr && !ublk_need_get_data(ubq))
-			goto out;
-		io->cmd = cmd;
-		io->flags |= UBLK_IO_FLAG_ACTIVE;
-		io->addr = ub_cmd->addr;
 
+		if (!ublk_support_user_copy(ubq)) {
+			/*
+			 * FETCH_RQ has to provide IO buffer if NEED GET
+			 * DATA is not enabled
+			 */
+			if (!ub_cmd->addr && !ublk_need_get_data(ubq))
+				goto out;
+		}
+
+		ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
 		ublk_mark_io_ready(ub, ubq);
 		break;
 	case UBLK_IO_COMMIT_AND_FETCH_REQ:
 		req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag);
-		/*
-		 * COMMIT_AND_FETCH_REQ has to provide IO buffer if NEED GET DATA is
-		 * not enabled or it is Read IO.
-		 */
-		if (!ub_cmd->addr && (!ublk_need_get_data(ubq) || req_op(req) == REQ_OP_READ))
-			goto out;
+
 		if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))
 			goto out;
-		io->addr = ub_cmd->addr;
-		io->flags |= UBLK_IO_FLAG_ACTIVE;
-		io->cmd = cmd;
+
+		if (!ublk_support_user_copy(ubq)) {
+			/*
+			 * COMMIT_AND_FETCH_REQ has to provide IO buffer if
+			 * NEED GET DATA is not enabled or it is Read IO.
+			 */
+			if (!ub_cmd->addr && (!ublk_need_get_data(ubq) ||
+						req_op(req) == REQ_OP_READ))
+				goto out;
+		}
+		ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
 		ublk_commit_completion(ub, ub_cmd);
 		break;
 	case UBLK_IO_NEED_GET_DATA:
 		if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))
 			goto out;
-		io->addr = ub_cmd->addr;
-		io->cmd = cmd;
-		io->flags |= UBLK_IO_FLAG_ACTIVE;
+		ublk_fill_io_cmd(io, cmd, ub_cmd->addr);
 		ublk_handle_need_get_data(ub, ub_cmd->q_id, ub_cmd->tag);
 		break;
 	default:
@@ -1402,6 +1486,36 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,
 	return -EIOCBQUEUED;
 }
 
+static inline struct request *__ublk_check_and_get_req(struct ublk_device *ub,
+		struct ublk_queue *ubq, int tag, size_t offset)
+{
+	struct request *req;
+
+	if (!ublk_need_req_ref(ubq))
+		return NULL;
+
+	req = blk_mq_tag_to_rq(ub->tag_set.tags[ubq->q_id], tag);
+	if (!req)
+		return NULL;
+
+	if (!ublk_get_req_ref(ubq, req))
+		return NULL;
+
+	if (unlikely(!blk_mq_request_started(req) || req->tag != tag))
+		goto fail_put;
+
+	if (!ublk_rq_has_data(req))
+		goto fail_put;
+
+	if (offset > blk_rq_bytes(req))
+		goto fail_put;
+
+	return req;
+fail_put:
+	ublk_put_req_ref(ubq, req);
+	return NULL;
+}
+
 static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
 {
 	/*
@@ -1419,11 +1533,112 @@ static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
 	return __ublk_ch_uring_cmd(cmd, issue_flags, &ub_cmd);
 }
 
+static inline bool ublk_check_ubuf_dir(const struct request *req,
+		int ubuf_dir)
+{
+	/* copy ubuf to request pages */
+	if (req_op(req) == REQ_OP_READ && ubuf_dir == ITER_SOURCE)
+		return true;
+
+	/* copy request pages to ubuf */
+	if (req_op(req) == REQ_OP_WRITE && ubuf_dir == ITER_DEST)
+		return true;
+
+	return false;
+}
+
+static struct request *ublk_check_and_get_req(struct kiocb *iocb,
+		struct iov_iter *iter, size_t *off, int dir)
+{
+	struct ublk_device *ub = iocb->ki_filp->private_data;
+	struct ublk_queue *ubq;
+	struct request *req;
+	size_t buf_off;
+	u16 tag, q_id;
+
+	if (!ub)
+		return ERR_PTR(-EACCES);
+
+	if (!user_backed_iter(iter))
+		return ERR_PTR(-EACCES);
+
+	if (ub->dev_info.state == UBLK_S_DEV_DEAD)
+		return ERR_PTR(-EACCES);
+
+	tag = ublk_pos_to_tag(iocb->ki_pos);
+	q_id = ublk_pos_to_hwq(iocb->ki_pos);
+	buf_off = ublk_pos_to_buf_off(iocb->ki_pos);
+
+	if (q_id >= ub->dev_info.nr_hw_queues)
+		return ERR_PTR(-EINVAL);
+
+	ubq = ublk_get_queue(ub, q_id);
+	if (!ubq)
+		return ERR_PTR(-EINVAL);
+
+	if (tag >= ubq->q_depth)
+		return ERR_PTR(-EINVAL);
+
+	req = __ublk_check_and_get_req(ub, ubq, tag, buf_off);
+	if (!req)
+		return ERR_PTR(-EINVAL);
+
+	if (!req->mq_hctx || !req->mq_hctx->driver_data)
+		goto fail;
+
+	if (!ublk_check_ubuf_dir(req, dir))
+		goto fail;
+
+	*off = buf_off;
+	return req;
+fail:
+	ublk_put_req_ref(ubq, req);
+	return ERR_PTR(-EACCES);
+}
+
+static ssize_t ublk_ch_read_iter(struct kiocb *iocb, struct iov_iter *to)
+{
+	struct ublk_queue *ubq;
+	struct request *req;
+	size_t buf_off;
+	size_t ret;
+
+	req = ublk_check_and_get_req(iocb, to, &buf_off, ITER_DEST);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	ret = ublk_copy_user_pages(req, buf_off, to, ITER_DEST);
+	ubq = req->mq_hctx->driver_data;
+	ublk_put_req_ref(ubq, req);
+
+	return ret;
+}
+
+static ssize_t ublk_ch_write_iter(struct kiocb *iocb, struct iov_iter *from)
+{
+	struct ublk_queue *ubq;
+	struct request *req;
+	size_t buf_off;
+	size_t ret;
+
+	req = ublk_check_and_get_req(iocb, from, &buf_off, ITER_SOURCE);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+
+	ret = ublk_copy_user_pages(req, buf_off, from, ITER_SOURCE);
+	ubq = req->mq_hctx->driver_data;
+	ublk_put_req_ref(ubq, req);
+
+	return ret;
+}
+
 static const struct file_operations ublk_ch_fops = {
 	.owner = THIS_MODULE,
 	.open = ublk_ch_open,
 	.release = ublk_ch_release,
 	.llseek = no_llseek,
+	.read_iter = ublk_ch_read_iter,
+	.write_iter = ublk_ch_write_iter,
 	.uring_cmd = ublk_ch_uring_cmd,
 	.mmap = ublk_ch_mmap,
 };
@@ -1547,7 +1762,7 @@ static int ublk_add_chdev(struct ublk_device *ub)
 
 	dev->parent = ublk_misc.this_device;
 	dev->devt = MKDEV(MAJOR(ublk_chr_devt), minor);
-	dev->class = ublk_chr_class;
+	dev->class = &ublk_chr_class;
 	dev->release = ublk_cdev_rel;
 	device_initialize(dev);
 
@@ -1818,10 +2033,12 @@ static int ublk_ctrl_add_dev(struct io_uring_cmd *cmd)
 	 */
 	ub->dev_info.flags &= UBLK_F_ALL;
 
-	if (!IS_BUILTIN(CONFIG_BLK_DEV_UBLK))
-		ub->dev_info.flags |= UBLK_F_URING_CMD_COMP_IN_TASK;
+	ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE |
+		UBLK_F_URING_CMD_COMP_IN_TASK;
 
-	ub->dev_info.flags |= UBLK_F_CMD_IOCTL_ENCODE;
+	/* GET_DATA isn't needed any more with USER_COPY */
+	if (ub->dev_info.flags & UBLK_F_USER_COPY)
+		ub->dev_info.flags &= ~UBLK_F_NEED_GET_DATA;
 
 	/* We are not ready to support zero copy */
 	ub->dev_info.flags &= ~UBLK_F_SUPPORT_ZERO_COPY;
@@ -2133,6 +2350,21 @@ static int ublk_ctrl_end_recovery(struct ublk_device *ub,
 	return ret;
 }
 
+static int ublk_ctrl_get_features(struct io_uring_cmd *cmd)
+{
+	const struct ublksrv_ctrl_cmd *header = io_uring_sqe_cmd(cmd->sqe);
+	void __user *argp = (void __user *)(unsigned long)header->addr;
+	u64 features = UBLK_F_ALL & ~UBLK_F_SUPPORT_ZERO_COPY;
+
+	if (header->len != UBLK_FEATURES_LEN || !header->addr)
+		return -EINVAL;
+
+	if (copy_to_user(argp, &features, UBLK_FEATURES_LEN))
+		return -EFAULT;
+
+	return 0;
+}
+
 /*
  * All control commands are sent via /dev/ublk-control, so we have to check
  * the destination device's permission
@@ -2213,6 +2445,7 @@ static int ublk_ctrl_uring_cmd_permission(struct ublk_device *ub,
 	case UBLK_CMD_GET_DEV_INFO2:
 	case UBLK_CMD_GET_QUEUE_AFFINITY:
 	case UBLK_CMD_GET_PARAMS:
+	case (_IOC_NR(UBLK_U_CMD_GET_FEATURES)):
 		mask = MAY_READ;
 		break;
 	case UBLK_CMD_START_DEV:
@@ -2262,6 +2495,11 @@ static int ublk_ctrl_uring_cmd(struct io_uring_cmd *cmd,
 	if (ret)
 		goto out;
 
+	if (cmd_op == UBLK_U_CMD_GET_FEATURES) {
+		ret = ublk_ctrl_get_features(cmd);
+		goto out;
+	}
+
 	if (_IOC_NR(cmd_op) != UBLK_CMD_ADD_DEV) {
 		ret = -ENODEV;
 		ub = ublk_get_device_from_id(header->dev_id);
@@ -2337,6 +2575,9 @@ static int __init ublk_init(void)
 {
 	int ret;
 
+	BUILD_BUG_ON((u64)UBLKSRV_IO_BUF_OFFSET +
+			UBLKSRV_IO_BUF_TOTAL_SIZE < UBLKSRV_IO_BUF_OFFSET);
+
 	init_waitqueue_head(&ublk_idr_wq);
 
 	ret = misc_register(&ublk_misc);
@@ -2347,11 +2588,10 @@ static int __init ublk_init(void)
 	if (ret)
 		goto unregister_mis;
 
-	ublk_chr_class = class_create("ublk-char");
-	if (IS_ERR(ublk_chr_class)) {
-		ret = PTR_ERR(ublk_chr_class);
+	ret = class_register(&ublk_chr_class);
+	if (ret)
 		goto free_chrdev_region;
-	}
+
 	return 0;
 
 free_chrdev_region:
@@ -2369,7 +2609,7 @@ static void __exit ublk_exit(void)
 	idr_for_each_entry(&ublk_index_idr, ub, id)
 		ublk_remove(ub);
 
-	class_destroy(ublk_chr_class);
+	class_unregister(&ublk_chr_class);
 	misc_deregister(&ublk_misc);
 
 	idr_destroy(&ublk_index_idr);
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index 4807af1d5805..bb66178c432b 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -473,7 +473,7 @@ static void xenvbd_sysfs_delif(struct xenbus_device *dev)
 static void xen_vbd_free(struct xen_vbd *vbd)
 {
 	if (vbd->bdev)
-		blkdev_put(vbd->bdev, vbd->readonly ? FMODE_READ : FMODE_WRITE);
+		blkdev_put(vbd->bdev, NULL);
 	vbd->bdev = NULL;
 }
 
@@ -492,7 +492,7 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 	vbd->pdevice  = MKDEV(major, minor);
 
 	bdev = blkdev_get_by_dev(vbd->pdevice, vbd->readonly ?
-				 FMODE_READ : FMODE_WRITE, NULL);
+				 BLK_OPEN_READ : BLK_OPEN_WRITE, NULL, NULL);
 
 	if (IS_ERR(bdev)) {
 		pr_warn("xen_vbd_create: device %08x could not be opened\n",
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index c1890c8a9f6e..434fab306777 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -509,7 +509,7 @@ static int blkif_getgeo(struct block_device *bd, struct hd_geometry *hg)
 	return 0;
 }
 
-static int blkif_ioctl(struct block_device *bdev, fmode_t mode,
+static int blkif_ioctl(struct block_device *bdev, blk_mode_t mode,
 		       unsigned command, unsigned long argument)
 {
 	struct blkfront_info *info = bdev->bd_disk->private_data;
diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index c1e85f356e4d..11493167b0a8 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -140,16 +140,14 @@ static void get_chipram(void)
 	return;
 }
 
-static int z2_open(struct block_device *bdev, fmode_t mode)
+static int z2_open(struct gendisk *disk, blk_mode_t mode)
 {
-	int device;
+	int device = disk->first_minor;
 	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);
-
 	mutex_lock(&z2ram_mutex);
 	if (current_device != -1 && current_device != device) {
 		rc = -EBUSY;
@@ -290,7 +288,7 @@ err_out:
 	return rc;
 }
 
-static void z2_release(struct gendisk *disk, fmode_t mode)
+static void z2_release(struct gendisk *disk)
 {
 	mutex_lock(&z2ram_mutex);
 	if (current_device == -1) {
diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index f6d90f1ba5cf..1867f378b319 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -420,7 +420,7 @@ static void reset_bdev(struct zram *zram)
 		return;
 
 	bdev = zram->bdev;
-	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
+	blkdev_put(bdev, zram);
 	/* hope filp_close flush all of IO */
 	filp_close(zram->backing_dev, NULL);
 	zram->backing_dev = NULL;
@@ -507,8 +507,8 @@ static ssize_t backing_dev_store(struct device *dev,
 		goto out;
 	}
 
-	bdev = blkdev_get_by_dev(inode->i_rdev,
-			FMODE_READ | FMODE_WRITE | FMODE_EXCL, zram);
+	bdev = blkdev_get_by_dev(inode->i_rdev, BLK_OPEN_READ | BLK_OPEN_WRITE,
+				 zram, NULL);
 	if (IS_ERR(bdev)) {
 		err = PTR_ERR(bdev);
 		bdev = NULL;
@@ -539,7 +539,7 @@ out:
 	kvfree(bitmap);
 
 	if (bdev)
-		blkdev_put(bdev, FMODE_READ | FMODE_WRITE | FMODE_EXCL);
+		blkdev_put(bdev, zram);
 
 	if (backing_dev)
 		filp_close(backing_dev, NULL);
@@ -700,7 +700,7 @@ static ssize_t writeback_store(struct device *dev,
 		bio_init(&bio, zram->bdev, &bio_vec, 1,
 			 REQ_OP_WRITE | REQ_SYNC);
 		bio.bi_iter.bi_sector = blk_idx * (PAGE_SIZE >> 9);
-		bio_add_page(&bio, page, PAGE_SIZE, 0);
+		__bio_add_page(&bio, page, PAGE_SIZE, 0);
 
 		/*
 		 * XXX: A single page IO would be inefficient for write
@@ -2097,19 +2097,16 @@ static ssize_t reset_store(struct device *dev,
 	return len;
 }
 
-static int zram_open(struct block_device *bdev, fmode_t mode)
+static int zram_open(struct gendisk *disk, blk_mode_t mode)
 {
-	int ret = 0;
-	struct zram *zram;
+	struct zram *zram = disk->private_data;
 
-	WARN_ON(!mutex_is_locked(&bdev->bd_disk->open_mutex));
+	WARN_ON(!mutex_is_locked(&disk->open_mutex));
 
-	zram = bdev->bd_disk->private_data;
 	/* zram was claimed to reset so open request fails */
 	if (zram->claim)
-		ret = -EBUSY;
-
-	return ret;
+		return -EBUSY;
+	return 0;
 }
 
 static const struct block_device_operations zram_devops = {