[PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Jan Kara]

Hello,

this is a v2 of the patch series which implements the idea of blkdev_get_by_*()
calls returning bdev_handle which is then passed to blkdev_put() [1]. This
makes the get and put calls for bdevs more obviously matching and allows us to
propagate context from get to put without having to modify all the users
(again!).  In particular I need to propagate used open flags to blkdev_put() to
be able count writeable opens and add support for blocking writes to mounted
block devices. I'll send that series separately.

The series is based on Christian's vfs tree as of yesterday as there is quite
some overlap. Patches have passed some reasonable testing - I've tested block
changes, md, dm, bcache, xfs, btrfs, ext4, swap. This obviously doesn't cover
everything so I'd like to ask respective maintainers to review / test their
changes. Thanks! I've pushed out the full branch to:

git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git bdev_handle

to ease review / testing.

Changes since v1:
* Rebased on top of current vfs tree
* Renamed final functions to bdev_open_by_*() and bdev_release()
* Fixed detection of exclusive open in blkdev_ioctl() and blkdev_fallocate()
* Fixed swap conversion to properly reinitialize swap_info->bdev_handle
* Fixed xfs conversion to not oops with rtdev without logdev
* Couple other minor fixups

								Honza

[1] https://lore.kernel.org/all/ZJGNsVDhZx0Xgs2H@infradead.org

CC: Alasdair Kergon <agk@redhat.com>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: Anna Schumaker <anna@kernel.org>
CC: Chao Yu <chao@kernel.org>
CC: Christian Borntraeger <borntraeger@linux.ibm.com>
CC: Coly Li <colyli@suse.de
CC: "Darrick J. Wong" <djwong@kernel.org>
CC: Dave Kleikamp <shaggy@kernel.org>
CC: David Sterba <dsterba@suse.com>
CC: dm-devel@redhat.com
CC: drbd-dev@lists.linbit.com
CC: Gao Xiang <xiang@kernel.org>
CC: Jack Wang <jinpu.wang@ionos.com>
CC: Jaegeuk Kim <jaegeuk@kernel.org>
CC: jfs-discussion@lists.sourceforge.net
CC: Joern Engel <joern@lazybastard.org>
CC: Joseph Qi <joseph.qi@linux.alibaba.com>
CC: Kent Overstreet <kent.overstreet@gmail.com>
CC: linux-bcache@vger.kernel.org
CC: linux-btrfs@vger.kernel.org
CC: linux-erofs@lists.ozlabs.org
CC: <linux-ext4@vger.kernel.org>
CC: linux-f2fs-devel@lists.sourceforge.net
CC: linux-mm@kvack.org
CC: linux-mtd@lists.infradead.org
CC: linux-nfs@vger.kernel.org
CC: linux-nilfs@vger.kernel.org
CC: linux-nvme@lists.infradead.org
CC: linux-pm@vger.kernel.org
CC: linux-raid@vger.kernel.org
CC: linux-s390@vger.kernel.org
CC: linux-scsi@vger.kernel.org
CC: linux-xfs@vger.kernel.org
CC: "Md. Haris Iqbal" <haris.iqbal@ionos.com>
CC: Mike Snitzer <snitzer@kernel.org>
CC: Minchan Kim <minchan@kernel.org>
CC: ocfs2-devel@oss.oracle.com
CC: reiserfs-devel@vger.kernel.org
CC: Sergey Senozhatsky <senozhatsky@chromium.org>
CC: Song Liu <song@kernel.org>
CC: Sven Schnelle <svens@linux.ibm.com>
CC: target-devel@vger.kernel.org
CC: Ted Tso <tytso@mit.edu>
CC: Trond Myklebust <trond.myklebust@hammerspace.com>
CC: xen-devel@lists.xenproject.org

Previous versions:
Link: http://lore.kernel.org/r/20230629165206.383-1-jack@suse.cz # v1

[PATCH 01/29] block: Provide bdev_open_* functions

[Jan Kara]

Create struct bdev_handle that contains all parameters that need to be
passed to blkdev_put() and provide bdev_open_* functions that return
this structure instead of plain bdev pointer. This will eventually allow
us to pass one more argument to blkdev_put() (renamed to bdev_release())
without too much hassle.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 block/bdev.c           | 48 ++++++++++++++++++++++++++++++++++++++++++
 include/linux/blkdev.h | 10 +++++++++
 2 files changed, 58 insertions(+)

diff --git a/block/bdev.c b/block/bdev.c
index 979e28a46b98..74fc2aeaab2c 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -846,6 +846,25 @@ struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 }
 EXPORT_SYMBOL(blkdev_get_by_dev);
 
+struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
+				     const struct blk_holder_ops *hops)
+{
+	struct bdev_handle *handle = kmalloc(sizeof(*handle), GFP_KERNEL);
+	struct block_device *bdev;
+
+	if (!handle)
+		return ERR_PTR(-ENOMEM);
+	bdev = blkdev_get_by_dev(dev, mode, holder, hops);
+	if (IS_ERR(bdev)) {
+		kfree(handle);
+		return ERR_CAST(bdev);
+	}
+	handle->bdev = bdev;
+	handle->holder = holder;
+	return handle;
+}
+EXPORT_SYMBOL(bdev_open_by_dev);
+
 /**
  * blkdev_get_by_path - open a block device by name
  * @path: path to the block device to open
@@ -884,6 +903,28 @@ struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
 }
 EXPORT_SYMBOL(blkdev_get_by_path);
 
+struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
+		void *holder, const struct blk_holder_ops *hops)
+{
+	struct bdev_handle *handle;
+	dev_t dev;
+	int error;
+
+	error = lookup_bdev(path, &dev);
+	if (error)
+		return ERR_PTR(error);
+
+	handle = bdev_open_by_dev(dev, mode, holder, hops);
+	if (!IS_ERR(handle) && (mode & BLK_OPEN_WRITE) &&
+	    bdev_read_only(handle->bdev)) {
+		bdev_release(handle);
+		return ERR_PTR(-EACCES);
+	}
+
+	return handle;
+}
+EXPORT_SYMBOL(bdev_open_by_path);
+
 void blkdev_put(struct block_device *bdev, void *holder)
 {
 	struct gendisk *disk = bdev->bd_disk;
@@ -920,6 +961,13 @@ void blkdev_put(struct block_device *bdev, void *holder)
 }
 EXPORT_SYMBOL(blkdev_put);
 
+void bdev_release(struct bdev_handle *handle)
+{
+	blkdev_put(handle->bdev, handle->holder);
+	kfree(handle);
+}
+EXPORT_SYMBOL(bdev_release);
+
 /**
  * lookup_bdev() - Look up a struct block_device by name.
  * @pathname: Name of the block device in the filesystem.
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 83262702eea7..8bdaf89fd879 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1473,14 +1473,24 @@ extern const struct blk_holder_ops fs_holder_ops;
 #define sb_open_mode(flags) \
 	(BLK_OPEN_READ | (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE))
 
+struct bdev_handle {
+	struct block_device *bdev;
+	void *holder;
+};
+
 struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 		const struct blk_holder_ops *hops);
 struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
 		void *holder, const struct blk_holder_ops *hops);
+struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
+		const struct blk_holder_ops *hops);
+struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
+		void *holder, const struct blk_holder_ops *hops);
 int bd_prepare_to_claim(struct block_device *bdev, void *holder,
 		const struct blk_holder_ops *hops);
 void bd_abort_claiming(struct block_device *bdev, void *holder);
 void blkdev_put(struct block_device *bdev, void *holder);
+void bdev_release(struct bdev_handle *handle);
 
 /* just for blk-cgroup, don't use elsewhere */
 struct block_device *blkdev_get_no_open(dev_t dev);
-- 
2.35.3

[PATCH 02/29] block: Use bdev_open_by_dev() in blkdev_open()

[Jan Kara]

Convert blkdev_open() to use bdev_open_by_dev(). To be able to propagate
handle from blkdev_open() to blkdev_release() we need to stop using
existence of file->private_data to determine exclusive block device
opens. Use bdev_handle->mode for this purpose since file->f_flags
isn't usable for this (O_EXCL is cleared from the flags during open).

Signed-off-by: Jan Kara <jack@suse.cz>
---
 block/bdev.c           |  3 +++
 block/blk.h            |  1 -
 block/fops.c           | 33 +++++++++++++++------------------
 block/ioctl.c          |  4 ++--
 include/linux/blkdev.h |  1 +
 5 files changed, 21 insertions(+), 21 deletions(-)

diff --git a/block/bdev.c b/block/bdev.c
index 74fc2aeaab2c..32c0ef5abad4 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -861,6 +861,9 @@ struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 	}
 	handle->bdev = bdev;
 	handle->holder = holder;
+	if (holder)
+		mode |= BLK_OPEN_EXCL;
+	handle->mode = mode;
 	return handle;
 }
 EXPORT_SYMBOL(bdev_open_by_dev);
diff --git a/block/blk.h b/block/blk.h
index 608c5dcc516b..43b80dc78918 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -464,7 +464,6 @@ extern struct device_attribute dev_attr_events_poll_msecs;
 
 extern struct attribute_group blk_trace_attr_group;
 
-blk_mode_t file_to_blk_mode(struct file *file);
 int truncate_bdev_range(struct block_device *bdev, blk_mode_t mode,
 		loff_t lstart, loff_t lend);
 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg);
diff --git a/block/fops.c b/block/fops.c
index a286bf3325c5..6a3bc2b7d4f3 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -470,7 +470,7 @@ static int blkdev_fsync(struct file *filp, loff_t start, loff_t end,
 	return error;
 }
 
-blk_mode_t file_to_blk_mode(struct file *file)
+static blk_mode_t file_to_blk_mode(struct file *file)
 {
 	blk_mode_t mode = 0;
 
@@ -478,7 +478,7 @@ blk_mode_t file_to_blk_mode(struct file *file)
 		mode |= BLK_OPEN_READ;
 	if (file->f_mode & FMODE_WRITE)
 		mode |= BLK_OPEN_WRITE;
-	if (file->private_data)
+	if (file->f_flags & O_EXCL)
 		mode |= BLK_OPEN_EXCL;
 	if (file->f_flags & O_NDELAY)
 		mode |= BLK_OPEN_NDELAY;
@@ -496,7 +496,8 @@ blk_mode_t file_to_blk_mode(struct file *file)
 
 static int blkdev_open(struct inode *inode, struct file *filp)
 {
-	struct block_device *bdev;
+	struct bdev_handle *handle;
+	blk_mode_t mode;
 
 	/*
 	 * Preserve backwards compatibility and allow large file access
@@ -507,29 +508,24 @@ static int blkdev_open(struct inode *inode, struct file *filp)
 	filp->f_flags |= O_LARGEFILE;
 	filp->f_mode |= FMODE_BUF_RASYNC;
 
-	/*
-	 * Use the file private data to store the holder for exclusive openes.
-	 * file_to_blk_mode relies on it being present to set BLK_OPEN_EXCL.
-	 */
-	if (filp->f_flags & O_EXCL)
-		filp->private_data = filp;
-
-	bdev = blkdev_get_by_dev(inode->i_rdev, file_to_blk_mode(filp),
-				 filp->private_data, NULL);
-	if (IS_ERR(bdev))
-		return PTR_ERR(bdev);
+	mode = file_to_blk_mode(filp);
+	handle = bdev_open_by_dev(inode->i_rdev, mode,
+			mode & BLK_OPEN_EXCL ? filp : NULL, NULL);
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
 
-	if (bdev_nowait(bdev))
+	if (bdev_nowait(handle->bdev))
 		filp->f_mode |= FMODE_NOWAIT;
 
-	filp->f_mapping = bdev->bd_inode->i_mapping;
+	filp->f_mapping = handle->bdev->bd_inode->i_mapping;
 	filp->f_wb_err = filemap_sample_wb_err(filp->f_mapping);
+	filp->private_data = handle;
 	return 0;
 }
 
 static int blkdev_release(struct inode *inode, struct file *filp)
 {
-	blkdev_put(I_BDEV(filp->f_mapping->host), filp->private_data);
+	bdev_release(filp->private_data);
 	return 0;
 }
 
@@ -630,6 +626,7 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start,
 {
 	struct inode *inode = bdev_file_inode(file);
 	struct block_device *bdev = I_BDEV(inode);
+	blk_mode_t open_mode = ((struct bdev_handle *)file->private_data)->mode;
 	loff_t end = start + len - 1;
 	loff_t isize;
 	int error;
@@ -659,7 +656,7 @@ static long blkdev_fallocate(struct file *file, int mode, loff_t start,
 	filemap_invalidate_lock(inode->i_mapping);
 
 	/* Invalidate the page cache, including dirty pages. */
-	error = truncate_bdev_range(bdev, file_to_blk_mode(file), start, end);
+	error = truncate_bdev_range(bdev, open_mode, start, end);
 	if (error)
 		goto fail;
 
diff --git a/block/ioctl.c b/block/ioctl.c
index 3be11941fb2d..47f216d8697f 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -575,7 +575,7 @@ long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 {
 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
 	void __user *argp = (void __user *)arg;
-	blk_mode_t mode = file_to_blk_mode(file);
+	blk_mode_t mode = ((struct bdev_handle *)file->private_data)->mode;
 	int ret;
 
 	switch (cmd) {
@@ -636,7 +636,7 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 	void __user *argp = compat_ptr(arg);
 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
 	struct gendisk *disk = bdev->bd_disk;
-	blk_mode_t mode = file_to_blk_mode(file);
+	blk_mode_t mode = ((struct bdev_handle *)file->private_data)->mode;
 
 	switch (cmd) {
 	/* These need separate implementations for the data structure */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8bdaf89fd879..0e89ad5c645c 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1476,6 +1476,7 @@ extern const struct blk_holder_ops fs_holder_ops;
 struct bdev_handle {
 	struct block_device *bdev;
 	void *holder;
+	blk_mode_t mode;
 };
 
 struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
-- 
2.35.3

[PATCH 03/29] block: Use bdev_open_by_dev() in disk_scan_partitions() and blkdev_bszset()

[Jan Kara]

Convert disk_scan_partitions() and blkdev_bszset() to use
bdev_open_by_dev().

Signed-off-by: Jan Kara <jack@suse.cz>
---
 block/genhd.c | 12 ++++++------
 block/ioctl.c |  6 ++++--
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/block/genhd.c b/block/genhd.c
index 3d287b32d50d..ebb9cd3ec8c2 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -342,7 +342,7 @@ EXPORT_SYMBOL_GPL(disk_uevent);
 
 int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode)
 {
-	struct block_device *bdev;
+	struct bdev_handle *handle;
 	int ret = 0;
 
 	if (disk->flags & (GENHD_FL_NO_PART | GENHD_FL_HIDDEN))
@@ -366,12 +366,12 @@ int disk_scan_partitions(struct gendisk *disk, blk_mode_t mode)
 	}
 
 	set_bit(GD_NEED_PART_SCAN, &disk->state);
-	bdev = blkdev_get_by_dev(disk_devt(disk), mode & ~BLK_OPEN_EXCL, NULL,
-				 NULL);
-	if (IS_ERR(bdev))
-		ret =  PTR_ERR(bdev);
+	handle = bdev_open_by_dev(disk_devt(disk), mode & ~BLK_OPEN_EXCL, NULL,
+				  NULL);
+	if (IS_ERR(handle))
+		ret = PTR_ERR(handle);
 	else
-		blkdev_put(bdev, NULL);
+		bdev_release(handle);
 
 	/*
 	 * If blkdev_get_by_dev() failed early, GD_NEED_PART_SCAN is still set,
diff --git a/block/ioctl.c b/block/ioctl.c
index 47f216d8697f..e53a23007073 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -458,6 +458,7 @@ static int blkdev_bszset(struct block_device *bdev, blk_mode_t mode,
 		int __user *argp)
 {
 	int ret, n;
+	struct bdev_handle *handle;
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EACCES;
@@ -469,10 +470,11 @@ static int blkdev_bszset(struct block_device *bdev, blk_mode_t mode,
 	if (mode & BLK_OPEN_EXCL)
 		return set_blocksize(bdev, n);
 
-	if (IS_ERR(blkdev_get_by_dev(bdev->bd_dev, mode, &bdev, NULL)))
+	handle = bdev_open_by_dev(bdev->bd_dev, mode, &bdev, NULL);
+	if (IS_ERR(handle))
 		return -EBUSY;
 	ret = set_blocksize(bdev, n);
-	blkdev_put(bdev, &bdev);
+	bdev_release(handle);
 
 	return ret;
 }
-- 
2.35.3

[PATCH 04/29] drdb: Convert to use bdev_open_by_path()

[Jan Kara]

Convert drdb to use bdev_open_by_path().

CC: drbd-dev@lists.linbit.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/block/drbd/drbd_int.h |  2 ++
 drivers/block/drbd/drbd_nl.c  | 65 +++++++++++++++++------------------
 2 files changed, 34 insertions(+), 33 deletions(-)

diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h
index a30a5ed811be..f017e917612b 100644
--- a/drivers/block/drbd/drbd_int.h
+++ b/drivers/block/drbd/drbd_int.h
@@ -524,7 +524,9 @@ struct drbd_md {
 
 struct drbd_backing_dev {
 	struct block_device *backing_bdev;
+	struct bdev_handle *backing_bdev_handle;
 	struct block_device *md_bdev;
+	struct bdev_handle *md_bdev_handle;
 	struct drbd_md md;
 	struct disk_conf *disk_conf; /* RCU, for updates: resource->conf_update */
 	sector_t known_size; /* last known size of that backing device */
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c
index cddae6f4b00f..3a0052abf25c 100644
--- a/drivers/block/drbd/drbd_nl.c
+++ b/drivers/block/drbd/drbd_nl.c
@@ -82,7 +82,7 @@ static atomic_t notify_genl_seq = ATOMIC_INIT(2); /* two. */
 
 DEFINE_MUTEX(notification_mutex);
 
-/* used blkdev_get_by_path, to claim our meta data device(s) */
+/* used bdev_open_by_path, to claim our meta data device(s) */
 static char *drbd_m_holder = "Hands off! this is DRBD's meta data device.";
 
 static void drbd_adm_send_reply(struct sk_buff *skb, struct genl_info *info)
@@ -1634,43 +1634,45 @@ int drbd_adm_disk_opts(struct sk_buff *skb, struct genl_info *info)
 	return 0;
 }
 
-static struct block_device *open_backing_dev(struct drbd_device *device,
+static struct bdev_handle *open_backing_dev(struct drbd_device *device,
 		const char *bdev_path, void *claim_ptr, bool do_bd_link)
 {
-	struct block_device *bdev;
+	struct bdev_handle *handle;
 	int err = 0;
 
-	bdev = blkdev_get_by_path(bdev_path, BLK_OPEN_READ | BLK_OPEN_WRITE,
-				  claim_ptr, NULL);
-	if (IS_ERR(bdev)) {
+	handle = bdev_open_by_path(bdev_path, BLK_OPEN_READ | BLK_OPEN_WRITE,
+				   claim_ptr, NULL);
+	if (IS_ERR(handle)) {
 		drbd_err(device, "open(\"%s\") failed with %ld\n",
-				bdev_path, PTR_ERR(bdev));
-		return bdev;
+				bdev_path, PTR_ERR(handle));
+		return handle;
 	}
 
 	if (!do_bd_link)
-		return bdev;
+		return handle;
 
-	err = bd_link_disk_holder(bdev, device->vdisk);
+	err = bd_link_disk_holder(handle->bdev, device->vdisk);
 	if (err) {
-		blkdev_put(bdev, claim_ptr);
+		bdev_release(handle);
 		drbd_err(device, "bd_link_disk_holder(\"%s\", ...) failed with %d\n",
 				bdev_path, err);
-		bdev = ERR_PTR(err);
+		handle = ERR_PTR(err);
 	}
-	return bdev;
+	return handle;
 }
 
 static int open_backing_devices(struct drbd_device *device,
 		struct disk_conf *new_disk_conf,
 		struct drbd_backing_dev *nbc)
 {
-	struct block_device *bdev;
+	struct bdev_handle *handle;
 
-	bdev = open_backing_dev(device, new_disk_conf->backing_dev, device, true);
-	if (IS_ERR(bdev))
+	handle = open_backing_dev(device, new_disk_conf->backing_dev, device,
+				  true);
+	if (IS_ERR(handle))
 		return ERR_OPEN_DISK;
-	nbc->backing_bdev = bdev;
+	nbc->backing_bdev = handle->bdev;
+	nbc->backing_bdev_handle = handle;
 
 	/*
 	 * meta_dev_idx >= 0: external fixed size, possibly multiple
@@ -1680,7 +1682,7 @@ static int open_backing_devices(struct drbd_device *device,
 	 * should check it for you already; but if you don't, or
 	 * someone fooled it, we need to double check here)
 	 */
-	bdev = open_backing_dev(device, new_disk_conf->meta_dev,
+	handle = open_backing_dev(device, new_disk_conf->meta_dev,
 		/* claim ptr: device, if claimed exclusively; shared drbd_m_holder,
 		 * if potentially shared with other drbd minors */
 			(new_disk_conf->meta_dev_idx < 0) ? (void*)device : (void*)drbd_m_holder,
@@ -1688,20 +1690,21 @@ static int open_backing_devices(struct drbd_device *device,
 		 * as would happen with internal metadata. */
 			(new_disk_conf->meta_dev_idx != DRBD_MD_INDEX_FLEX_INT &&
 			 new_disk_conf->meta_dev_idx != DRBD_MD_INDEX_INTERNAL));
-	if (IS_ERR(bdev))
+	if (IS_ERR(handle))
 		return ERR_OPEN_MD_DISK;
-	nbc->md_bdev = bdev;
+	nbc->md_bdev = handle->bdev;
+	nbc->md_bdev_handle = handle;
 	return NO_ERROR;
 }
 
-static void close_backing_dev(struct drbd_device *device, struct block_device *bdev,
-		void *claim_ptr, bool do_bd_unlink)
+static void close_backing_dev(struct drbd_device *device,
+		struct bdev_handle *handle, bool do_bd_unlink)
 {
-	if (!bdev)
+	if (!handle)
 		return;
 	if (do_bd_unlink)
-		bd_unlink_disk_holder(bdev, device->vdisk);
-	blkdev_put(bdev, claim_ptr);
+		bd_unlink_disk_holder(handle->bdev, device->vdisk);
+	bdev_release(handle);
 }
 
 void drbd_backing_dev_free(struct drbd_device *device, struct drbd_backing_dev *ldev)
@@ -1709,11 +1712,9 @@ 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.meta_dev_idx < 0 ?
-				(void *)device : (void *)drbd_m_holder,
+	close_backing_dev(device, ldev->md_bdev_handle,
 			  ldev->md_bdev != ldev->backing_bdev);
-	close_backing_dev(device, ldev->backing_bdev, device, true);
+	close_backing_dev(device, ldev->backing_bdev_handle, true);
 
 	kfree(ldev->disk_conf);
 	kfree(ldev);
@@ -2129,11 +2130,9 @@ 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->disk_conf->meta_dev_idx < 0 ?
-				(void *)device : (void *)drbd_m_holder,
+		close_backing_dev(device, nbc->md_bdev_handle,
 			  nbc->md_bdev != nbc->backing_bdev);
-		close_backing_dev(device, nbc->backing_bdev, device, true);
+		close_backing_dev(device, nbc->backing_bdev_handle, true);
 		kfree(nbc);
 	}
 	kfree(new_disk_conf);
-- 
2.35.3

[PATCH 05/29] pktcdvd: Convert to bdev_open_by_dev()

[Jan Kara]

Convert pktcdvd to use bdev_open_by_dev().

Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/block/pktcdvd.c | 76 ++++++++++++++++++++++-------------------
 include/linux/pktcdvd.h |  4 ++-
 2 files changed, 44 insertions(+), 36 deletions(-)

diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index a1428538bda5..d56d972aadb3 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -340,8 +340,8 @@ static ssize_t device_map_show(const struct class *c, const struct class_attribu
 		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));
+			MAJOR(pd->bdev_handle->bdev->bd_dev),
+			MINOR(pd->bdev_handle->bdev->bd_dev));
 	}
 	mutex_unlock(&ctl_mutex);
 	return n;
@@ -437,7 +437,8 @@ static int pkt_seq_show(struct seq_file *m, void *p)
 	char *msg;
 	int states[PACKET_NUM_STATES];
 
-	seq_printf(m, "Writer %s mapped to %pg:\n", pd->disk->disk_name, pd->bdev);
+	seq_printf(m, "Writer %s mapped to %pg:\n", pd->disk->disk_name,
+		   pd->bdev_handle->bdev);
 
 	seq_printf(m, "\nSettings:\n");
 	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
@@ -714,7 +715,7 @@ static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *nod
  */
 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 {
-	struct request_queue *q = bdev_get_queue(pd->bdev);
+	struct request_queue *q = bdev_get_queue(pd->bdev_handle->bdev);
 	struct scsi_cmnd *scmd;
 	struct request *rq;
 	int ret = 0;
@@ -1047,7 +1048,8 @@ static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 			continue;
 
 		bio = pkt->r_bios[f];
-		bio_init(bio, pd->bdev, bio->bi_inline_vecs, 1, REQ_OP_READ);
+		bio_init(bio, pd->bdev_handle->bdev, bio->bi_inline_vecs, 1,
+			 REQ_OP_READ);
 		bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 		bio->bi_end_io = pkt_end_io_read;
 		bio->bi_private = pkt;
@@ -1262,8 +1264,8 @@ 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,
-		 REQ_OP_WRITE);
+	bio_init(pkt->w_bio, pd->bdev_handle->bdev, pkt->w_bio->bi_inline_vecs,
+		 pkt->frames, REQ_OP_WRITE);
 	pkt->w_bio->bi_iter.bi_sector = pkt->sector;
 	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
 	pkt->w_bio->bi_private = pkt;
@@ -2160,18 +2162,20 @@ static int pkt_open_dev(struct pktcdvd_device *pd, bool write)
 	int ret;
 	long lba;
 	struct request_queue *q;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 
 	/*
 	 * We need to re-open the cdrom device without O_NONBLOCK to be able
 	 * 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, BLK_OPEN_READ, pd, NULL);
-	if (IS_ERR(bdev)) {
-		ret = PTR_ERR(bdev);
+	bdev_handle = bdev_open_by_dev(pd->bdev_handle->bdev->bd_dev,
+				       BLK_OPEN_READ, pd, NULL);
+	if (IS_ERR(bdev_handle)) {
+		ret = PTR_ERR(bdev_handle);
 		goto out;
 	}
+	pd->open_bdev_handle = bdev_handle;
 
 	ret = pkt_get_last_written(pd, &lba);
 	if (ret) {
@@ -2180,9 +2184,9 @@ static int pkt_open_dev(struct pktcdvd_device *pd, bool write)
 	}
 
 	set_capacity(pd->disk, lba << 2);
-	set_capacity_and_notify(pd->bdev->bd_disk, lba << 2);
+	set_capacity_and_notify(pd->bdev_handle->bdev->bd_disk, lba << 2);
 
-	q = bdev_get_queue(pd->bdev);
+	q = bdev_get_queue(pd->bdev_handle->bdev);
 	if (write) {
 		ret = pkt_open_write(pd);
 		if (ret)
@@ -2214,7 +2218,7 @@ static int pkt_open_dev(struct pktcdvd_device *pd, bool write)
 	return 0;
 
 out_putdev:
-	blkdev_put(bdev, pd);
+	bdev_release(bdev_handle);
 out:
 	return ret;
 }
@@ -2233,7 +2237,8 @@ static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
 	pkt_lock_door(pd, 0);
 
 	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
-	blkdev_put(pd->bdev, pd);
+	bdev_release(pd->open_bdev_handle);
+	pd->open_bdev_handle = NULL;
 
 	pkt_shrink_pktlist(pd);
 }
@@ -2321,8 +2326,8 @@ static void pkt_end_io_read_cloned(struct bio *bio)
 
 static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
 {
-	struct bio *cloned_bio =
-		bio_alloc_clone(pd->bdev, bio, GFP_NOIO, &pkt_bio_set);
+	struct bio *cloned_bio = bio_alloc_clone(pd->bdev_handle->bdev, bio,
+		GFP_NOIO, &pkt_bio_set);
 	struct packet_stacked_data *psd = mempool_alloc(&psd_pool, GFP_NOIO);
 
 	psd->pd = pd;
@@ -2492,7 +2497,7 @@ 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 bdev_handle *bdev_handle;
 	struct scsi_device *sdev;
 
 	if (pd->pkt_dev == dev) {
@@ -2503,8 +2508,9 @@ static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 		struct pktcdvd_device *pd2 = pkt_devs[i];
 		if (!pd2)
 			continue;
-		if (pd2->bdev->bd_dev == dev) {
-			dev_err(ddev, "%pg already setup\n", pd2->bdev);
+		if (pd2->bdev_handle->bdev->bd_dev == dev) {
+			dev_err(ddev, "%pg already setup\n",
+				pd2->bdev_handle->bdev);
 			return -EBUSY;
 		}
 		if (pd2->pkt_dev == dev) {
@@ -2513,13 +2519,13 @@ static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 		}
 	}
 
-	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);
+	bdev_handle = bdev_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_NDELAY,
+				       NULL, NULL);
+	if (IS_ERR(bdev_handle))
+		return PTR_ERR(bdev_handle);
+	sdev = scsi_device_from_queue(bdev_handle->bdev->bd_disk->queue);
 	if (!sdev) {
-		blkdev_put(bdev, NULL);
+		bdev_release(bdev_handle);
 		return -EINVAL;
 	}
 	put_device(&sdev->sdev_gendev);
@@ -2527,8 +2533,8 @@ static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 	/* This is safe, since we have a reference from open(). */
 	__module_get(THIS_MODULE);
 
-	pd->bdev = bdev;
-	set_blocksize(bdev, CD_FRAMESIZE);
+	pd->bdev_handle = bdev_handle;
+	set_blocksize(bdev_handle->bdev, CD_FRAMESIZE);
 
 	pkt_init_queue(pd);
 
@@ -2540,11 +2546,11 @@ static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
 	}
 
 	proc_create_single_data(pd->disk->disk_name, 0, pkt_proc, pkt_seq_show, pd);
-	dev_notice(ddev, "writer mapped to %pg\n", bdev);
+	dev_notice(ddev, "writer mapped to %pg\n", bdev_handle->bdev);
 	return 0;
 
 out_mem:
-	blkdev_put(bdev, NULL);
+	bdev_release(bdev_handle);
 	/* This is safe: open() is still holding a reference. */
 	module_put(THIS_MODULE);
 	return -ENOMEM;
@@ -2599,9 +2605,9 @@ static unsigned int pkt_check_events(struct gendisk *disk,
 
 	if (!pd)
 		return 0;
-	if (!pd->bdev)
+	if (!pd->bdev_handle)
 		return 0;
-	attached_disk = pd->bdev->bd_disk;
+	attached_disk = pd->bdev_handle->bdev->bd_disk;
 	if (!attached_disk || !attached_disk->fops->check_events)
 		return 0;
 	return attached_disk->fops->check_events(attached_disk, clearing);
@@ -2686,7 +2692,7 @@ static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
 		goto out_mem2;
 
 	/* inherit events of the host device */
-	disk->events = pd->bdev->bd_disk->events;
+	disk->events = pd->bdev_handle->bdev->bd_disk->events;
 
 	ret = add_disk(disk);
 	if (ret)
@@ -2751,7 +2757,7 @@ static int pkt_remove_dev(dev_t pkt_dev)
 	pkt_debugfs_dev_remove(pd);
 	pkt_sysfs_dev_remove(pd);
 
-	blkdev_put(pd->bdev, NULL);
+	bdev_release(pd->bdev_handle);
 
 	remove_proc_entry(pd->disk->disk_name, pkt_proc);
 	dev_notice(ddev, "writer unmapped\n");
@@ -2778,7 +2784,7 @@ static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
 
 	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
 	if (pd) {
-		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
+		ctrl_cmd->dev = new_encode_dev(pd->bdev_handle->bdev->bd_dev);
 		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
 	} else {
 		ctrl_cmd->dev = 0;
diff --git a/include/linux/pktcdvd.h b/include/linux/pktcdvd.h
index 80cb00db42a4..79594aeb160d 100644
--- a/include/linux/pktcdvd.h
+++ b/include/linux/pktcdvd.h
@@ -154,7 +154,9 @@ struct packet_stacked_data
 
 struct pktcdvd_device
 {
-	struct block_device	*bdev;		/* dev attached */
+	struct bdev_handle	*bdev_handle;	/* dev attached */
+	/* handle acquired for bdev during pkt_open_dev() */
+	struct bdev_handle	*open_bdev_handle;
 	dev_t			pkt_dev;	/* our dev */
 	struct packet_settings	settings;
 	struct packet_stats	stats;
-- 
2.35.3

[PATCH 06/29] rnbd-srv: Convert to use bdev_open_by_path()

[Jan Kara]

Convert rnbd-srv to use bdev_open_by_path() and pass the handle
around.

CC: Jack Wang <jinpu.wang@ionos.com>
CC: "Md. Haris Iqbal" <haris.iqbal@ionos.com>
Acked-by: "Md. Haris Iqbal" <haris.iqbal@ionos.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/block/rnbd/rnbd-srv.c | 27 ++++++++++++++-------------
 drivers/block/rnbd/rnbd-srv.h |  2 +-
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/drivers/block/rnbd/rnbd-srv.c b/drivers/block/rnbd/rnbd-srv.c
index c186df0ec641..65de51f3dfd9 100644
--- a/drivers/block/rnbd/rnbd-srv.c
+++ b/drivers/block/rnbd/rnbd-srv.c
@@ -145,7 +145,7 @@ static int process_rdma(struct rnbd_srv_session *srv_sess,
 	priv->sess_dev = sess_dev;
 	priv->id = id;
 
-	bio = bio_alloc(sess_dev->bdev, 1,
+	bio = bio_alloc(sess_dev->bdev_handle->bdev, 1,
 			rnbd_to_bio_flags(le32_to_cpu(msg->rw)), GFP_KERNEL);
 	if (bio_add_page(bio, virt_to_page(data), datalen,
 			offset_in_page(data)) != datalen) {
@@ -219,7 +219,7 @@ 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, NULL);
+	bdev_release(sess_dev->bdev_handle);
 	mutex_lock(&sess_dev->dev->lock);
 	list_del(&sess_dev->dev_list);
 	if (!sess_dev->readonly)
@@ -534,7 +534,7 @@ rnbd_srv_get_or_create_srv_dev(struct block_device *bdev,
 static void rnbd_srv_fill_msg_open_rsp(struct rnbd_msg_open_rsp *rsp,
 					struct rnbd_srv_sess_dev *sess_dev)
 {
-	struct block_device *bdev = sess_dev->bdev;
+	struct block_device *bdev = sess_dev->bdev_handle->bdev;
 
 	rsp->hdr.type = cpu_to_le16(RNBD_MSG_OPEN_RSP);
 	rsp->device_id = cpu_to_le32(sess_dev->device_id);
@@ -559,7 +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, bool readonly,
+			      struct bdev_handle *handle, bool readonly,
 			      struct rnbd_srv_dev *srv_dev)
 {
 	struct rnbd_srv_sess_dev *sdev = rnbd_sess_dev_alloc(srv_sess);
@@ -571,7 +571,7 @@ rnbd_srv_create_set_sess_dev(struct rnbd_srv_session *srv_sess,
 
 	strscpy(sdev->pathname, open_msg->dev_name, sizeof(sdev->pathname));
 
-	sdev->bdev		= bdev;
+	sdev->bdev_handle	= handle;
 	sdev->sess		= srv_sess;
 	sdev->dev		= srv_dev;
 	sdev->readonly		= readonly;
@@ -676,7 +676,7 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 	struct rnbd_srv_dev *srv_dev;
 	struct rnbd_srv_sess_dev *srv_sess_dev;
 	const struct rnbd_msg_open *open_msg = msg;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	blk_mode_t open_flags = BLK_OPEN_READ;
 	char *full_path;
 	struct rnbd_msg_open_rsp *rsp = data;
@@ -714,15 +714,15 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 		goto reject;
 	}
 
-	bdev = blkdev_get_by_path(full_path, open_flags, NULL, NULL);
-	if (IS_ERR(bdev)) {
-		ret = PTR_ERR(bdev);
+	bdev_handle = bdev_open_by_path(full_path, open_flags, NULL, NULL);
+	if (IS_ERR(bdev_handle)) {
+		ret = PTR_ERR(bdev_handle);
 		pr_err("Opening device '%s' on session %s failed, failed to open the block device, err: %d\n",
 		       full_path, srv_sess->sessname, ret);
 		goto free_path;
 	}
 
-	srv_dev = rnbd_srv_get_or_create_srv_dev(bdev, srv_sess,
+	srv_dev = rnbd_srv_get_or_create_srv_dev(bdev_handle->bdev, srv_sess,
 						  open_msg->access_mode);
 	if (IS_ERR(srv_dev)) {
 		pr_err("Opening device '%s' on session %s failed, creating srv_dev failed, err: %ld\n",
@@ -731,7 +731,8 @@ 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,
+	srv_sess_dev = rnbd_srv_create_set_sess_dev(srv_sess, open_msg,
+				bdev_handle,
 				open_msg->access_mode == RNBD_ACCESS_RO,
 				srv_dev);
 	if (IS_ERR(srv_sess_dev)) {
@@ -747,7 +748,7 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 	 */
 	mutex_lock(&srv_dev->lock);
 	if (!srv_dev->dev_kobj.state_in_sysfs) {
-		ret = rnbd_srv_create_dev_sysfs(srv_dev, bdev);
+		ret = rnbd_srv_create_dev_sysfs(srv_dev, bdev_handle->bdev);
 		if (ret) {
 			mutex_unlock(&srv_dev->lock);
 			rnbd_srv_err(srv_sess_dev,
@@ -790,7 +791,7 @@ static int process_msg_open(struct rnbd_srv_session *srv_sess,
 	}
 	rnbd_put_srv_dev(srv_dev);
 blkdev_put:
-	blkdev_put(bdev, NULL);
+	bdev_release(bdev_handle);
 free_path:
 	kfree(full_path);
 reject:
diff --git a/drivers/block/rnbd/rnbd-srv.h b/drivers/block/rnbd/rnbd-srv.h
index 1027656dedb0..343cc682b617 100644
--- a/drivers/block/rnbd/rnbd-srv.h
+++ b/drivers/block/rnbd/rnbd-srv.h
@@ -46,7 +46,7 @@ struct rnbd_srv_dev {
 struct rnbd_srv_sess_dev {
 	/* Entry inside rnbd_srv_dev struct */
 	struct list_head		dev_list;
-	struct block_device		*bdev;
+	struct bdev_handle		*bdev_handle;
 	struct rnbd_srv_session		*sess;
 	struct rnbd_srv_dev		*dev;
 	struct kobject                  kobj;
-- 
2.35.3

[PATCH 07/29] xen/blkback: Convert to bdev_open_by_dev()

[Jan Kara]

Convert xen/blkback to use bdev_open_by_dev() and pass the
handle around.

CC: xen-devel@lists.xenproject.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/block/xen-blkback/blkback.c |  4 +--
 drivers/block/xen-blkback/common.h  |  4 +--
 drivers/block/xen-blkback/xenbus.c  | 40 +++++++++++++++--------------
 3 files changed, 25 insertions(+), 23 deletions(-)

diff --git a/drivers/block/xen-blkback/blkback.c b/drivers/block/xen-blkback/blkback.c
index c362f4ad80ab..4defd7f387c7 100644
--- a/drivers/block/xen-blkback/blkback.c
+++ b/drivers/block/xen-blkback/blkback.c
@@ -465,7 +465,7 @@ static int xen_vbd_translate(struct phys_req *req, struct xen_blkif *blkif,
 	}
 
 	req->dev  = vbd->pdevice;
-	req->bdev = vbd->bdev;
+	req->bdev = vbd->bdev_handle->bdev;
 	rc = 0;
 
  out:
@@ -969,7 +969,7 @@ static int dispatch_discard_io(struct xen_blkif_ring *ring,
 	int err = 0;
 	int status = BLKIF_RSP_OKAY;
 	struct xen_blkif *blkif = ring->blkif;
-	struct block_device *bdev = blkif->vbd.bdev;
+	struct block_device *bdev = blkif->vbd.bdev_handle->bdev;
 	struct phys_req preq;
 
 	xen_blkif_get(blkif);
diff --git a/drivers/block/xen-blkback/common.h b/drivers/block/xen-blkback/common.h
index 40f67bfc052d..5ff50e76cee5 100644
--- a/drivers/block/xen-blkback/common.h
+++ b/drivers/block/xen-blkback/common.h
@@ -221,7 +221,7 @@ struct xen_vbd {
 	unsigned char		type;
 	/* phys device that this vbd maps to. */
 	u32			pdevice;
-	struct block_device	*bdev;
+	struct bdev_handle	*bdev_handle;
 	/* Cached size parameter. */
 	sector_t		size;
 	unsigned int		flush_support:1;
@@ -360,7 +360,7 @@ struct pending_req {
 };
 
 
-#define vbd_sz(_v)	bdev_nr_sectors((_v)->bdev)
+#define vbd_sz(_v)	bdev_nr_sectors((_v)->bdev_handle->bdev)
 
 #define xen_blkif_get(_b) (atomic_inc(&(_b)->refcnt))
 #define xen_blkif_put(_b)				\
diff --git a/drivers/block/xen-blkback/xenbus.c b/drivers/block/xen-blkback/xenbus.c
index bb66178c432b..e34219ea2b05 100644
--- a/drivers/block/xen-blkback/xenbus.c
+++ b/drivers/block/xen-blkback/xenbus.c
@@ -81,7 +81,7 @@ static void xen_update_blkif_status(struct xen_blkif *blkif)
 	int i;
 
 	/* Not ready to connect? */
-	if (!blkif->rings || !blkif->rings[0].irq || !blkif->vbd.bdev)
+	if (!blkif->rings || !blkif->rings[0].irq || !blkif->vbd.bdev_handle)
 		return;
 
 	/* Already connected? */
@@ -99,12 +99,13 @@ static void xen_update_blkif_status(struct xen_blkif *blkif)
 		return;
 	}
 
-	err = sync_blockdev(blkif->vbd.bdev);
+	err = sync_blockdev(blkif->vbd.bdev_handle->bdev);
 	if (err) {
 		xenbus_dev_error(blkif->be->dev, err, "block flush");
 		return;
 	}
-	invalidate_inode_pages2(blkif->vbd.bdev->bd_inode->i_mapping);
+	invalidate_inode_pages2(
+			blkif->vbd.bdev_handle->bdev->bd_inode->i_mapping);
 
 	for (i = 0; i < blkif->nr_rings; i++) {
 		ring = &blkif->rings[i];
@@ -472,9 +473,9 @@ 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, NULL);
-	vbd->bdev = NULL;
+	if (vbd->bdev_handle)
+		bdev_release(vbd->bdev_handle);
+	vbd->bdev_handle = NULL;
 }
 
 static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
@@ -482,7 +483,7 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 			  int cdrom)
 {
 	struct xen_vbd *vbd;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 
 	vbd = &blkif->vbd;
 	vbd->handle   = handle;
@@ -491,17 +492,17 @@ 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 ?
+	bdev_handle = bdev_open_by_dev(vbd->pdevice, vbd->readonly ?
 				 BLK_OPEN_READ : BLK_OPEN_WRITE, NULL, NULL);
 
-	if (IS_ERR(bdev)) {
+	if (IS_ERR(bdev_handle)) {
 		pr_warn("xen_vbd_create: device %08x could not be opened\n",
 			vbd->pdevice);
 		return -ENOENT;
 	}
 
-	vbd->bdev = bdev;
-	if (vbd->bdev->bd_disk == NULL) {
+	vbd->bdev_handle = bdev_handle;
+	if (vbd->bdev_handle->bdev->bd_disk == NULL) {
 		pr_warn("xen_vbd_create: device %08x doesn't exist\n",
 			vbd->pdevice);
 		xen_vbd_free(vbd);
@@ -509,14 +510,14 @@ static int xen_vbd_create(struct xen_blkif *blkif, blkif_vdev_t handle,
 	}
 	vbd->size = vbd_sz(vbd);
 
-	if (cdrom || disk_to_cdi(vbd->bdev->bd_disk))
+	if (cdrom || disk_to_cdi(vbd->bdev_handle->bdev->bd_disk))
 		vbd->type |= VDISK_CDROM;
-	if (vbd->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
+	if (vbd->bdev_handle->bdev->bd_disk->flags & GENHD_FL_REMOVABLE)
 		vbd->type |= VDISK_REMOVABLE;
 
-	if (bdev_write_cache(bdev))
+	if (bdev_write_cache(bdev_handle->bdev))
 		vbd->flush_support = true;
-	if (bdev_max_secure_erase_sectors(bdev))
+	if (bdev_max_secure_erase_sectors(bdev_handle->bdev))
 		vbd->discard_secure = true;
 
 	pr_debug("Successful creation of handle=%04x (dom=%u)\n",
@@ -569,7 +570,7 @@ static void xen_blkbk_discard(struct xenbus_transaction xbt, struct backend_info
 	struct xen_blkif *blkif = be->blkif;
 	int err;
 	int state = 0;
-	struct block_device *bdev = be->blkif->vbd.bdev;
+	struct block_device *bdev = be->blkif->vbd.bdev_handle->bdev;
 
 	if (!xenbus_read_unsigned(dev->nodename, "discard-enable", 1))
 		return;
@@ -930,15 +931,16 @@ static void connect(struct backend_info *be)
 		goto abort;
 	}
 	err = xenbus_printf(xbt, dev->nodename, "sector-size", "%lu",
-			    (unsigned long)
-			    bdev_logical_block_size(be->blkif->vbd.bdev));
+			    (unsigned long)bdev_logical_block_size(
+					be->blkif->vbd.bdev_handle->bdev));
 	if (err) {
 		xenbus_dev_fatal(dev, err, "writing %s/sector-size",
 				 dev->nodename);
 		goto abort;
 	}
 	err = xenbus_printf(xbt, dev->nodename, "physical-sector-size", "%u",
-			    bdev_physical_block_size(be->blkif->vbd.bdev));
+			    bdev_physical_block_size(
+					be->blkif->vbd.bdev_handle->bdev));
 	if (err)
 		xenbus_dev_error(dev, err, "writing %s/physical-sector-size",
 				 dev->nodename);
-- 
2.35.3

[PATCH 08/29] zram: Convert to use bdev_open_by_dev()

[Jan Kara]

Convert zram to use bdev_open_by_dev() and pass the handle around.

CC: Minchan Kim <minchan@kernel.org>
CC: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/block/zram/zram_drv.c | 31 ++++++++++++++-----------------
 drivers/block/zram/zram_drv.h |  2 +-
 2 files changed, 15 insertions(+), 18 deletions(-)

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index 5676e6dd5b16..dfbb102d9c79 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -414,17 +414,14 @@ static ssize_t writeback_limit_show(struct device *dev,
 
 static void reset_bdev(struct zram *zram)
 {
-	struct block_device *bdev;
-
 	if (!zram->backing_dev)
 		return;
 
-	bdev = zram->bdev;
-	blkdev_put(bdev, zram);
+	bdev_release(zram->bdev_handle);
 	/* hope filp_close flush all of IO */
 	filp_close(zram->backing_dev, NULL);
 	zram->backing_dev = NULL;
-	zram->bdev = NULL;
+	zram->bdev_handle = NULL;
 	zram->disk->fops = &zram_devops;
 	kvfree(zram->bitmap);
 	zram->bitmap = NULL;
@@ -470,7 +467,7 @@ static ssize_t backing_dev_store(struct device *dev,
 	struct address_space *mapping;
 	unsigned int bitmap_sz;
 	unsigned long nr_pages, *bitmap = NULL;
-	struct block_device *bdev = NULL;
+	struct bdev_handle *bdev_handle = NULL;
 	int err;
 	struct zram *zram = dev_to_zram(dev);
 
@@ -507,11 +504,11 @@ static ssize_t backing_dev_store(struct device *dev,
 		goto out;
 	}
 
-	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;
+	bdev_handle = bdev_open_by_dev(inode->i_rdev,
+				BLK_OPEN_READ | BLK_OPEN_WRITE, zram, NULL);
+	if (IS_ERR(bdev_handle)) {
+		err = PTR_ERR(bdev_handle);
+		bdev_handle = NULL;
 		goto out;
 	}
 
@@ -525,7 +522,7 @@ static ssize_t backing_dev_store(struct device *dev,
 
 	reset_bdev(zram);
 
-	zram->bdev = bdev;
+	zram->bdev_handle = bdev_handle;
 	zram->backing_dev = backing_dev;
 	zram->bitmap = bitmap;
 	zram->nr_pages = nr_pages;
@@ -538,8 +535,8 @@ static ssize_t backing_dev_store(struct device *dev,
 out:
 	kvfree(bitmap);
 
-	if (bdev)
-		blkdev_put(bdev, zram);
+	if (bdev_handle)
+		bdev_release(bdev_handle);
 
 	if (backing_dev)
 		filp_close(backing_dev, NULL);
@@ -581,7 +578,7 @@ static void read_from_bdev_async(struct zram *zram, struct page *page,
 {
 	struct bio *bio;
 
-	bio = bio_alloc(zram->bdev, 1, parent->bi_opf, GFP_NOIO);
+	bio = bio_alloc(zram->bdev_handle->bdev, 1, parent->bi_opf, GFP_NOIO);
 	bio->bi_iter.bi_sector = entry * (PAGE_SIZE >> 9);
 	__bio_add_page(bio, page, PAGE_SIZE, 0);
 	bio_chain(bio, parent);
@@ -697,7 +694,7 @@ static ssize_t writeback_store(struct device *dev,
 			continue;
 		}
 
-		bio_init(&bio, zram->bdev, &bio_vec, 1,
+		bio_init(&bio, zram->bdev_handle->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);
@@ -779,7 +776,7 @@ static void zram_sync_read(struct work_struct *work)
 	struct bio_vec bv;
 	struct bio bio;
 
-	bio_init(&bio, zw->zram->bdev, &bv, 1, REQ_OP_READ);
+	bio_init(&bio, zw->zram->bdev_handle->bdev, &bv, 1, REQ_OP_READ);
 	bio.bi_iter.bi_sector = zw->entry * (PAGE_SIZE >> 9);
 	__bio_add_page(&bio, zw->page, PAGE_SIZE, 0);
 	zw->error = submit_bio_wait(&bio);
diff --git a/drivers/block/zram/zram_drv.h b/drivers/block/zram/zram_drv.h
index ca7a15bd4845..d090753f97be 100644
--- a/drivers/block/zram/zram_drv.h
+++ b/drivers/block/zram/zram_drv.h
@@ -132,7 +132,7 @@ struct zram {
 	spinlock_t wb_limit_lock;
 	bool wb_limit_enable;
 	u64 bd_wb_limit;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	unsigned long *bitmap;
 	unsigned long nr_pages;
 #endif
-- 
2.35.3

[PATCH 09/29] bcache: Convert to bdev_open_by_path()

[Jan Kara]

Convert bcache to use bdev_open_by_path() and pass the handle around.

CC: linux-bcache@vger.kernel.org
CC: Coly Li <colyli@suse.de
CC: Kent Overstreet <kent.overstreet@gmail.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/md/bcache/bcache.h |  2 +
 drivers/md/bcache/super.c  | 78 ++++++++++++++++++++------------------
 2 files changed, 43 insertions(+), 37 deletions(-)

diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
index 5a79bb3c272f..2aa3f2c1f719 100644
--- a/drivers/md/bcache/bcache.h
+++ b/drivers/md/bcache/bcache.h
@@ -299,6 +299,7 @@ struct cached_dev {
 	struct list_head	list;
 	struct bcache_device	disk;
 	struct block_device	*bdev;
+	struct bdev_handle	*bdev_handle;
 
 	struct cache_sb		sb;
 	struct cache_sb_disk	*sb_disk;
@@ -421,6 +422,7 @@ struct cache {
 
 	struct kobject		kobj;
 	struct block_device	*bdev;
+	struct bdev_handle	*bdev_handle;
 
 	struct task_struct	*alloc_thread;
 
diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 0ae2b3676293..c11ac86be72b 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -1368,8 +1368,8 @@ static void cached_dev_free(struct closure *cl)
 	if (dc->sb_disk)
 		put_page(virt_to_page(dc->sb_disk));
 
-	if (!IS_ERR_OR_NULL(dc->bdev))
-		blkdev_put(dc->bdev, dc);
+	if (dc->bdev_handle)
+		bdev_release(dc->bdev_handle);
 
 	wake_up(&unregister_wait);
 
@@ -1444,7 +1444,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
 /* Cached device - bcache superblock */
 
 static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
-				 struct block_device *bdev,
+				 struct bdev_handle *bdev_handle,
 				 struct cached_dev *dc)
 {
 	const char *err = "cannot allocate memory";
@@ -1452,14 +1452,15 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 	int ret = -ENOMEM;
 
 	memcpy(&dc->sb, sb, sizeof(struct cache_sb));
-	dc->bdev = bdev;
+	dc->bdev_handle = bdev_handle;
+	dc->bdev = bdev_handle->bdev;
 	dc->sb_disk = sb_disk;
 
 	if (cached_dev_init(dc, sb->block_size << 9))
 		goto err;
 
 	err = "error creating kobject";
-	if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache"))
+	if (kobject_add(&dc->disk.kobj, bdev_kobj(dc->bdev), "bcache"))
 		goto err;
 	if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
 		goto err;
@@ -2216,8 +2217,8 @@ void bch_cache_release(struct kobject *kobj)
 	if (ca->sb_disk)
 		put_page(virt_to_page(ca->sb_disk));
 
-	if (!IS_ERR_OR_NULL(ca->bdev))
-		blkdev_put(ca->bdev, ca);
+	if (ca->bdev_handle)
+		bdev_release(ca->bdev_handle);
 
 	kfree(ca);
 	module_put(THIS_MODULE);
@@ -2337,16 +2338,18 @@ static int cache_alloc(struct cache *ca)
 }
 
 static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
-				struct block_device *bdev, struct cache *ca)
+				struct bdev_handle *bdev_handle,
+				struct cache *ca)
 {
 	const char *err = NULL; /* must be set for any error case */
 	int ret = 0;
 
 	memcpy(&ca->sb, sb, sizeof(struct cache_sb));
-	ca->bdev = bdev;
+	ca->bdev_handle = bdev_handle;
+	ca->bdev = bdev_handle->bdev;
 	ca->sb_disk = sb_disk;
 
-	if (bdev_max_discard_sectors((bdev)))
+	if (bdev_max_discard_sectors((bdev_handle->bdev)))
 		ca->discard = CACHE_DISCARD(&ca->sb);
 
 	ret = cache_alloc(ca);
@@ -2354,10 +2357,10 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 		/*
 		 * If we failed here, it means ca->kobj is not initialized yet,
 		 * kobject_put() won't be called and there is no chance to
-		 * call blkdev_put() to bdev in bch_cache_release(). So we
-		 * explicitly call blkdev_put() here.
+		 * call bdev_release() to bdev in bch_cache_release(). So
+		 * we explicitly call bdev_release() here.
 		 */
-		blkdev_put(bdev, ca);
+		bdev_release(bdev_handle);
 		if (ret == -ENOMEM)
 			err = "cache_alloc(): -ENOMEM";
 		else if (ret == -EPERM)
@@ -2367,7 +2370,7 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 		goto err;
 	}
 
-	if (kobject_add(&ca->kobj, bdev_kobj(bdev), "bcache")) {
+	if (kobject_add(&ca->kobj, bdev_kobj(bdev_handle->bdev), "bcache")) {
 		err = "error calling kobject_add";
 		ret = -ENOMEM;
 		goto out;
@@ -2382,14 +2385,14 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
 		goto out;
 	}
 
-	pr_info("registered cache device %pg\n", ca->bdev);
+	pr_info("registered cache device %pg\n", ca->bdev_handle->bdev);
 
 out:
 	kobject_put(&ca->kobj);
 
 err:
 	if (err)
-		pr_notice("error %pg: %s\n", ca->bdev, err);
+		pr_notice("error %pg: %s\n", ca->bdev_handle->bdev, err);
 
 	return ret;
 }
@@ -2445,7 +2448,7 @@ struct async_reg_args {
 	char *path;
 	struct cache_sb *sb;
 	struct cache_sb_disk *sb_disk;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	void *holder;
 };
 
@@ -2456,8 +2459,8 @@ static void register_bdev_worker(struct work_struct *work)
 		container_of(work, struct async_reg_args, reg_work.work);
 
 	mutex_lock(&bch_register_lock);
-	if (register_bdev(args->sb, args->sb_disk, args->bdev, args->holder)
-	    < 0)
+	if (register_bdev(args->sb, args->sb_disk, args->bdev_handle,
+			  args->holder) < 0)
 		fail = true;
 	mutex_unlock(&bch_register_lock);
 
@@ -2477,7 +2480,8 @@ static void register_cache_worker(struct work_struct *work)
 		container_of(work, struct async_reg_args, reg_work.work);
 
 	/* blkdev_put() will be called in bch_cache_release() */
-	if (register_cache(args->sb, args->sb_disk, args->bdev, args->holder))
+	if (register_cache(args->sb, args->sb_disk, args->bdev_handle,
+			   args->holder))
 		fail = true;
 
 	if (fail)
@@ -2514,7 +2518,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 	char *path = NULL;
 	struct cache_sb *sb;
 	struct cache_sb_disk *sb_disk;
-	struct block_device *bdev, *bdev2;
+	struct bdev_handle *bdev_handle, *bdev_handle2;
 	void *holder = NULL;
 	ssize_t ret;
 	bool async_registration = false;
@@ -2547,15 +2551,15 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 
 	ret = -EINVAL;
 	err = "failed to open device";
-	bdev = blkdev_get_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
-	if (IS_ERR(bdev))
+	bdev_handle = bdev_open_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
+	if (IS_ERR(bdev_handle))
 		goto out_free_sb;
 
 	err = "failed to set blocksize";
-	if (set_blocksize(bdev, 4096))
+	if (set_blocksize(bdev_handle->bdev, 4096))
 		goto out_blkdev_put;
 
-	err = read_super(sb, bdev, &sb_disk);
+	err = read_super(sb, bdev_handle->bdev, &sb_disk);
 	if (err)
 		goto out_blkdev_put;
 
@@ -2567,13 +2571,13 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 	}
 
 	/* Now reopen in exclusive mode with proper holder */
-	bdev2 = blkdev_get_by_dev(bdev->bd_dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
-				  holder, NULL);
-	blkdev_put(bdev, NULL);
-	bdev = bdev2;
-	if (IS_ERR(bdev)) {
-		ret = PTR_ERR(bdev);
-		bdev = NULL;
+	bdev_handle2 = bdev_open_by_dev(bdev_handle->bdev->bd_dev,
+			BLK_OPEN_READ | BLK_OPEN_WRITE, holder, NULL);
+	bdev_release(bdev_handle);
+	bdev_handle = bdev_handle2;
+	if (IS_ERR(bdev_handle)) {
+		ret = PTR_ERR(bdev_handle);
+		bdev_handle = NULL;
 		if (ret == -EBUSY) {
 			dev_t dev;
 
@@ -2608,7 +2612,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 		args->path	= path;
 		args->sb	= sb;
 		args->sb_disk	= sb_disk;
-		args->bdev	= bdev;
+		args->bdev_handle	= bdev_handle;
 		args->holder	= holder;
 		register_device_async(args);
 		/* No wait and returns to user space */
@@ -2617,14 +2621,14 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 
 	if (SB_IS_BDEV(sb)) {
 		mutex_lock(&bch_register_lock);
-		ret = register_bdev(sb, sb_disk, bdev, holder);
+		ret = register_bdev(sb, sb_disk, bdev_handle, holder);
 		mutex_unlock(&bch_register_lock);
 		/* blkdev_put() will be called in cached_dev_free() */
 		if (ret < 0)
 			goto out_free_sb;
 	} else {
 		/* blkdev_put() will be called in bch_cache_release() */
-		ret = register_cache(sb, sb_disk, bdev, holder);
+		ret = register_cache(sb, sb_disk, bdev_handle, holder);
 		if (ret)
 			goto out_free_sb;
 	}
@@ -2640,8 +2644,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
 out_put_sb_page:
 	put_page(virt_to_page(sb_disk));
 out_blkdev_put:
-	if (bdev)
-		blkdev_put(bdev, holder);
+	if (bdev_handle)
+		bdev_release(bdev_handle);
 out_free_sb:
 	kfree(sb);
 out_free_path:
-- 
2.35.3

[PATCH 10/29] dm: Convert to bdev_open_by_dev()

[Jan Kara]

Convert device mapper to use bdev_open_by_dev() and pass the handle
around.

CC: Alasdair Kergon <agk@redhat.com>
CC: Mike Snitzer <snitzer@kernel.org>
CC: dm-devel@redhat.com
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/md/dm.c               | 20 +++++++++++---------
 include/linux/device-mapper.h |  1 +
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index f0f118ab20fa..efde77d34f15 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -742,7 +742,7 @@ static struct table_device *open_table_device(struct mapped_device *md,
 		dev_t dev, blk_mode_t mode)
 {
 	struct table_device *td;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	u64 part_off;
 	int r;
 
@@ -751,9 +751,9 @@ static struct table_device *open_table_device(struct mapped_device *md,
 		return ERR_PTR(-ENOMEM);
 	refcount_set(&td->count, 1);
 
-	bdev = blkdev_get_by_dev(dev, mode, _dm_claim_ptr, NULL);
-	if (IS_ERR(bdev)) {
-		r = PTR_ERR(bdev);
+	bdev_handle = bdev_open_by_dev(dev, mode, _dm_claim_ptr, NULL);
+	if (IS_ERR(bdev_handle)) {
+		r = PTR_ERR(bdev_handle);
 		goto out_free_td;
 	}
 
@@ -763,20 +763,22 @@ static struct table_device *open_table_device(struct mapped_device *md,
 	 * called.
 	 */
 	if (md->disk->slave_dir) {
-		r = bd_link_disk_holder(bdev, md->disk);
+		r = bd_link_disk_holder(bdev_handle->bdev, md->disk);
 		if (r)
 			goto out_blkdev_put;
 	}
 
 	td->dm_dev.mode = mode;
-	td->dm_dev.bdev = bdev;
-	td->dm_dev.dax_dev = fs_dax_get_by_bdev(bdev, &part_off, NULL, NULL);
+	td->dm_dev.bdev = bdev_handle->bdev;
+	td->dm_dev.bdev_handle = bdev_handle;
+	td->dm_dev.dax_dev = fs_dax_get_by_bdev(bdev_handle->bdev, &part_off,
+						NULL, NULL);
 	format_dev_t(td->dm_dev.name, dev);
 	list_add(&td->list, &md->table_devices);
 	return td;
 
 out_blkdev_put:
-	blkdev_put(bdev, _dm_claim_ptr);
+	bdev_release(bdev_handle);
 out_free_td:
 	kfree(td);
 	return ERR_PTR(r);
@@ -789,7 +791,7 @@ static void close_table_device(struct table_device *td, struct mapped_device *md
 {
 	if (md->disk->slave_dir)
 		bd_unlink_disk_holder(td->dm_dev.bdev, md->disk);
-	blkdev_put(td->dm_dev.bdev, _dm_claim_ptr);
+	bdev_release(td->dm_dev.bdev_handle);
 	put_dax(td->dm_dev.dax_dev);
 	list_del(&td->list);
 	kfree(td);
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 69d0435c7ebb..772ab4d74d94 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -165,6 +165,7 @@ void dm_error(const char *message);
 
 struct dm_dev {
 	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	struct dax_device *dax_dev;
 	blk_mode_t mode;
 	char name[16];
-- 
2.35.3

[PATCH 11/29] md: Convert to bdev_open_by_dev()

[Jan Kara]

Convert md to use bdev_open_by_dev() and pass the handle around.

CC: linux-raid@vger.kernel.org
CC: Song Liu <song@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/md/md.c | 12 +++++++-----
 drivers/md/md.h |  1 +
 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 78be7811a89f..20d6cefda3e8 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2450,7 +2450,7 @@ static void export_rdev(struct md_rdev *rdev, struct mddev *mddev)
 	if (test_bit(AutoDetected, &rdev->flags))
 		md_autodetect_dev(rdev->bdev->bd_dev);
 #endif
-	blkdev_put(rdev->bdev, mddev->external ? &claim_rdev : rdev);
+	bdev_release(rdev->bdev_handle);
 	rdev->bdev = NULL;
 	kobject_put(&rdev->kobj);
 }
@@ -3644,14 +3644,16 @@ static struct md_rdev *md_import_device(dev_t newdev, int super_format, int supe
 	if (err)
 		goto out_clear_rdev;
 
-	rdev->bdev = blkdev_get_by_dev(newdev, BLK_OPEN_READ | BLK_OPEN_WRITE,
+	rdev->bdev_handle = bdev_open_by_dev(newdev,
+			BLK_OPEN_READ | BLK_OPEN_WRITE,
 			super_format == -2 ? &claim_rdev : rdev, NULL);
-	if (IS_ERR(rdev->bdev)) {
+	if (IS_ERR(rdev->bdev_handle)) {
 		pr_warn("md: could not open device unknown-block(%u,%u).\n",
 			MAJOR(newdev), MINOR(newdev));
-		err = PTR_ERR(rdev->bdev);
+		err = PTR_ERR(rdev->bdev_handle);
 		goto out_clear_rdev;
 	}
+	rdev->bdev = rdev->bdev_handle->bdev;
 
 	kobject_init(&rdev->kobj, &rdev_ktype);
 
@@ -3682,7 +3684,7 @@ static struct md_rdev *md_import_device(dev_t newdev, int super_format, int supe
 	return rdev;
 
 out_blkdev_put:
-	blkdev_put(rdev->bdev, super_format == -2 ? &claim_rdev : rdev);
+	bdev_release(rdev->bdev_handle);
 out_clear_rdev:
 	md_rdev_clear(rdev);
 out_free_rdev:
diff --git a/drivers/md/md.h b/drivers/md/md.h
index 1aef86bf3fc3..e8108845157b 100644
--- a/drivers/md/md.h
+++ b/drivers/md/md.h
@@ -59,6 +59,7 @@ struct md_rdev {
 	 */
 	struct block_device *meta_bdev;
 	struct block_device *bdev;	/* block device handle */
+	struct bdev_handle *bdev_handle;	/* Handle from open for bdev */
 
 	struct page	*sb_page, *bb_page;
 	int		sb_loaded;
-- 
2.35.3

[PATCH 12/29] mtd: block2mtd: Convert to bdev_open_by_dev/path()

[Jan Kara]

Convert block2mtd to use bdev_open_by_dev() and bdev_open_by_path() and
pass the handle around.

CC: Joern Engel <joern@lazybastard.org>
CC: linux-mtd@lists.infradead.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/mtd/devices/block2mtd.c | 51 +++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 22 deletions(-)

diff --git a/drivers/mtd/devices/block2mtd.c b/drivers/mtd/devices/block2mtd.c
index be106dc20ff3..aa44a23ec045 100644
--- a/drivers/mtd/devices/block2mtd.c
+++ b/drivers/mtd/devices/block2mtd.c
@@ -37,7 +37,7 @@
 /* Info for the block device */
 struct block2mtd_dev {
 	struct list_head list;
-	struct block_device *blkdev;
+	struct bdev_handle *bdev_handle;
 	struct mtd_info mtd;
 	struct mutex write_mutex;
 };
@@ -55,7 +55,8 @@ static struct page *page_read(struct address_space *mapping, pgoff_t index)
 /* erase a specified part of the device */
 static int _block2mtd_erase(struct block2mtd_dev *dev, loff_t to, size_t len)
 {
-	struct address_space *mapping = dev->blkdev->bd_inode->i_mapping;
+	struct address_space *mapping =
+				dev->bdev_handle->bdev->bd_inode->i_mapping;
 	struct page *page;
 	pgoff_t index = to >> PAGE_SHIFT;	// page index
 	int pages = len >> PAGE_SHIFT;
@@ -105,6 +106,8 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
 		size_t *retlen, u_char *buf)
 {
 	struct block2mtd_dev *dev = mtd->priv;
+	struct address_space *mapping =
+				dev->bdev_handle->bdev->bd_inode->i_mapping;
 	struct page *page;
 	pgoff_t index = from >> PAGE_SHIFT;
 	int offset = from & (PAGE_SIZE-1);
@@ -117,7 +120,7 @@ static int block2mtd_read(struct mtd_info *mtd, loff_t from, size_t len,
 			cpylen = len;	// this page
 		len = len - cpylen;
 
-		page = page_read(dev->blkdev->bd_inode->i_mapping, index);
+		page = page_read(mapping, index);
 		if (IS_ERR(page))
 			return PTR_ERR(page);
 
@@ -139,7 +142,8 @@ static int _block2mtd_write(struct block2mtd_dev *dev, const u_char *buf,
 		loff_t to, size_t len, size_t *retlen)
 {
 	struct page *page;
-	struct address_space *mapping = dev->blkdev->bd_inode->i_mapping;
+	struct address_space *mapping =
+				dev->bdev_handle->bdev->bd_inode->i_mapping;
 	pgoff_t index = to >> PAGE_SHIFT;	// page index
 	int offset = to & ~PAGE_MASK;	// page offset
 	int cpylen;
@@ -194,7 +198,7 @@ static int block2mtd_write(struct mtd_info *mtd, loff_t to, size_t len,
 static void block2mtd_sync(struct mtd_info *mtd)
 {
 	struct block2mtd_dev *dev = mtd->priv;
-	sync_blockdev(dev->blkdev);
+	sync_blockdev(dev->bdev_handle->bdev);
 	return;
 }
 
@@ -206,10 +210,10 @@ static void block2mtd_free_device(struct block2mtd_dev *dev)
 
 	kfree(dev->mtd.name);
 
-	if (dev->blkdev) {
-		invalidate_mapping_pages(dev->blkdev->bd_inode->i_mapping,
-					0, -1);
-		blkdev_put(dev->blkdev, NULL);
+	if (dev->bdev_handle) {
+		invalidate_mapping_pages(
+			dev->bdev_handle->bdev->bd_inode->i_mapping, 0, -1);
+		bdev_release(dev->bdev_handle);
 	}
 
 	kfree(dev);
@@ -219,10 +223,10 @@ static void block2mtd_free_device(struct block2mtd_dev *dev)
  * This function is marked __ref because it calls the __init marked
  * early_lookup_bdev when called from the early boot code.
  */
-static struct block_device __ref *mdtblock_early_get_bdev(const char *devname,
+static struct bdev_handle __ref *mdtblock_early_get_bdev(const char *devname,
 		blk_mode_t mode, int timeout, struct block2mtd_dev *dev)
 {
-	struct block_device *bdev = ERR_PTR(-ENODEV);
+	struct bdev_handle *bdev_handle = ERR_PTR(-ENODEV);
 #ifndef MODULE
 	int i;
 
@@ -230,7 +234,7 @@ static struct block_device __ref *mdtblock_early_get_bdev(const char *devname,
 	 * We can't use early_lookup_bdev from a running system.
 	 */
 	if (system_state >= SYSTEM_RUNNING)
-		return bdev;
+		return bdev_handle;
 
 	/*
 	 * We might not have the root device mounted at this point.
@@ -249,19 +253,20 @@ static struct block_device __ref *mdtblock_early_get_bdev(const char *devname,
 		wait_for_device_probe();
 
 		if (!early_lookup_bdev(devname, &devt)) {
-			bdev = blkdev_get_by_dev(devt, mode, dev, NULL);
-			if (!IS_ERR(bdev))
+			bdev_handle = bdev_open_by_dev(devt, mode, dev, NULL);
+			if (!IS_ERR(bdev_handle))
 				break;
 		}
 	}
 #endif
-	return bdev;
+	return bdev_handle;
 }
 
 static struct block2mtd_dev *add_device(char *devname, int erase_size,
 		char *label, int timeout)
 {
 	const blk_mode_t mode = BLK_OPEN_READ | BLK_OPEN_WRITE;
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 	struct block2mtd_dev *dev;
 	char *name;
@@ -274,21 +279,23 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size,
 		return NULL;
 
 	/* Get a handle on the device */
-	bdev = blkdev_get_by_path(devname, mode, dev, NULL);
-	if (IS_ERR(bdev))
-		bdev = mdtblock_early_get_bdev(devname, mode, timeout, dev);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_path(devname, mode, dev, NULL);
+	if (IS_ERR(bdev_handle))
+		bdev_handle = mdtblock_early_get_bdev(devname, mode, timeout,
+						      dev);
+	if (IS_ERR(bdev_handle)) {
 		pr_err("error: cannot open device %s\n", devname);
 		goto err_free_block2mtd;
 	}
-	dev->blkdev = bdev;
+	dev->bdev_handle = bdev_handle;
+	bdev = bdev_handle->bdev;
 
 	if (MAJOR(bdev->bd_dev) == MTD_BLOCK_MAJOR) {
 		pr_err("attempting to use an MTD device as a block device\n");
 		goto err_free_block2mtd;
 	}
 
-	if ((long)dev->blkdev->bd_inode->i_size % erase_size) {
+	if ((long)bdev->bd_inode->i_size % erase_size) {
 		pr_err("erasesize must be a divisor of device size\n");
 		goto err_free_block2mtd;
 	}
@@ -306,7 +313,7 @@ static struct block2mtd_dev *add_device(char *devname, int erase_size,
 
 	dev->mtd.name = name;
 
-	dev->mtd.size = dev->blkdev->bd_inode->i_size & PAGE_MASK;
+	dev->mtd.size = bdev->bd_inode->i_size & PAGE_MASK;
 	dev->mtd.erasesize = erase_size;
 	dev->mtd.writesize = 1;
 	dev->mtd.writebufsize = PAGE_SIZE;
-- 
2.35.3

[PATCH 13/29] nvmet: Convert to bdev_open_by_path()

[Jan Kara]

Convert nvmet to use bdev_open_by_path() and pass the handle around.

CC: linux-nvme@lists.infradead.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/nvme/target/io-cmd-bdev.c | 20 +++++++++++---------
 drivers/nvme/target/nvmet.h       |  1 +
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index 2733e0158585..0bf05c19d8b5 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -50,9 +50,10 @@ void nvmet_bdev_set_limits(struct block_device *bdev, struct nvme_id_ns *id)
 
 void nvmet_bdev_ns_disable(struct nvmet_ns *ns)
 {
-	if (ns->bdev) {
-		blkdev_put(ns->bdev, NULL);
+	if (ns->bdev_handle) {
+		bdev_release(ns->bdev_handle);
 		ns->bdev = NULL;
+		ns->bdev_handle = NULL;
 	}
 }
 
@@ -84,17 +85,18 @@ int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
 	if (ns->buffered_io)
 		return -ENOTBLK;
 
-	ns->bdev = blkdev_get_by_path(ns->device_path,
-			BLK_OPEN_READ | BLK_OPEN_WRITE, NULL, NULL);
-	if (IS_ERR(ns->bdev)) {
-		ret = PTR_ERR(ns->bdev);
+	ns->bdev_handle = bdev_open_by_path(ns->device_path,
+				BLK_OPEN_READ | BLK_OPEN_WRITE, NULL, NULL);
+	if (IS_ERR(ns->bdev_handle)) {
+		ret = PTR_ERR(ns->bdev_handle);
 		if (ret != -ENOTBLK) {
-			pr_err("failed to open block device %s: (%ld)\n",
-					ns->device_path, PTR_ERR(ns->bdev));
+			pr_err("failed to open block device %s: (%d)\n",
+					ns->device_path, ret);
 		}
-		ns->bdev = NULL;
+		ns->bdev_handle = NULL;
 		return ret;
 	}
+	ns->bdev = ns->bdev_handle->bdev;
 	ns->size = bdev_nr_bytes(ns->bdev);
 	ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
 
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 8cfd60f3b564..360e385be33b 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -58,6 +58,7 @@
 
 struct nvmet_ns {
 	struct percpu_ref	ref;
+	struct bdev_handle	*bdev_handle;
 	struct block_device	*bdev;
 	struct file		*file;
 	bool			readonly;
-- 
2.35.3

[PATCH 14/29] s390/dasd: Convert to bdev_open_by_path()

[Jan Kara]

Convert dasd to use bdev_open_by_path() and pass the handle around.

CC: linux-s390@vger.kernel.org
CC: Christian Borntraeger <borntraeger@linux.ibm.com>
CC: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/s390/block/dasd.c       | 12 +++++----
 drivers/s390/block/dasd_genhd.c | 45 ++++++++++++++++-----------------
 drivers/s390/block/dasd_int.h   |  2 +-
 drivers/s390/block/dasd_ioctl.c |  2 +-
 4 files changed, 31 insertions(+), 30 deletions(-)

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 50a5ff70814a..b12f5719193f 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -412,7 +412,8 @@ dasd_state_ready_to_online(struct dasd_device * device)
 					KOBJ_CHANGE);
 			return 0;
 		}
-		disk_uevent(device->block->bdev->bd_disk, KOBJ_CHANGE);
+		disk_uevent(device->block->bdev_handle->bdev->bd_disk,
+			    KOBJ_CHANGE);
 	}
 	return 0;
 }
@@ -432,7 +433,8 @@ static int dasd_state_online_to_ready(struct dasd_device *device)
 
 	device->state = DASD_STATE_READY;
 	if (device->block && !(device->features & DASD_FEATURE_USERAW))
-		disk_uevent(device->block->bdev->bd_disk, KOBJ_CHANGE);
+		disk_uevent(device->block->bdev_handle->bdev->bd_disk,
+			    KOBJ_CHANGE);
 	return 0;
 }
 
@@ -3590,7 +3592,7 @@ int dasd_generic_set_offline(struct ccw_device *cdev)
 	 * in the other openers.
 	 */
 	if (device->block) {
-		max_count = device->block->bdev ? 0 : -1;
+		max_count = device->block->bdev_handle ? 0 : -1;
 		open_count = atomic_read(&device->block->open_count);
 		if (open_count > max_count) {
 			if (open_count > 0)
@@ -3636,8 +3638,8 @@ int dasd_generic_set_offline(struct ccw_device *cdev)
 		 * so sync bdev first and then wait for our queues to become
 		 * empty
 		 */
-		if (device->block) {
-			rc = fsync_bdev(device->block->bdev);
+		if (device->block && device->block->bdev_handle) {
+			rc = fsync_bdev(device->block->bdev_handle->bdev);
 			if (rc != 0)
 				goto interrupted;
 		}
diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index fe5108a1b332..55e3abe94cde 100644
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -127,15 +127,15 @@ void dasd_gendisk_free(struct dasd_block *block)
  */
 int dasd_scan_partitions(struct dasd_block *block)
 {
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	int rc;
 
-	bdev = blkdev_get_by_dev(disk_devt(block->gdp), BLK_OPEN_READ, NULL,
-				 NULL);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_dev(disk_devt(block->gdp), BLK_OPEN_READ,
+				       NULL, NULL);
+	if (IS_ERR(bdev_handle)) {
 		DBF_DEV_EVENT(DBF_ERR, block->base,
 			      "scan partitions error, blkdev_get returned %ld",
-			      PTR_ERR(bdev));
+			      PTR_ERR(bdev_handle));
 		return -ENODEV;
 	}
 
@@ -147,16 +147,15 @@ int dasd_scan_partitions(struct dasd_block *block)
 				"scan partitions error, rc %d", rc);
 
 	/*
-	 * Since the matching blkdev_put call to the blkdev_get in
-	 * this function is not called before dasd_destroy_partitions
-	 * the offline open_count limit needs to be increased from
-	 * 0 to 1. This is done by setting device->bdev (see
-	 * dasd_generic_set_offline). As long as the partition
-	 * detection is running no offline should be allowed. That
-	 * is why the assignment to device->bdev is done AFTER
-	 * the BLKRRPART ioctl.
+	 * Since the matching bdev_release() call to the
+	 * bdev_open_by_path() in this function is not called before
+	 * dasd_destroy_partitions the offline open_count limit needs to be
+	 * increased from 0 to 1. This is done by setting device->bdev_handle
+	 * (see dasd_generic_set_offline). As long as the partition detection
+	 * is running no offline should be allowed. That is why the assignment
+	 * to block->bdev_handle is done AFTER the BLKRRPART ioctl.
 	 */
-	block->bdev = bdev;
+	block->bdev_handle = bdev_handle;
 	return 0;
 }
 
@@ -166,21 +165,21 @@ int dasd_scan_partitions(struct dasd_block *block)
  */
 void dasd_destroy_partitions(struct dasd_block *block)
 {
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 
 	/*
-	 * Get the bdev pointer from the device structure and clear
-	 * device->bdev to lower the offline open_count limit again.
+	 * Get the bdev_handle pointer from the device structure and clear
+	 * device->bdev_handle to lower the offline open_count limit again.
 	 */
-	bdev = block->bdev;
-	block->bdev = NULL;
+	bdev_handle = block->bdev_handle;
+	block->bdev_handle = NULL;
 
-	mutex_lock(&bdev->bd_disk->open_mutex);
-	bdev_disk_changed(bdev->bd_disk, true);
-	mutex_unlock(&bdev->bd_disk->open_mutex);
+	mutex_lock(&bdev_handle->bdev->bd_disk->open_mutex);
+	bdev_disk_changed(bdev_handle->bdev->bd_disk, true);
+	mutex_unlock(&bdev_handle->bdev->bd_disk->open_mutex);
 
 	/* Matching blkdev_put to the blkdev_get in dasd_scan_partitions. */
-	blkdev_put(bdev, NULL);
+	bdev_release(bdev_handle);
 }
 
 int dasd_gendisk_init(void)
diff --git a/drivers/s390/block/dasd_int.h b/drivers/s390/block/dasd_int.h
index 0aa56351da72..73c5eb0ae6ad 100644
--- a/drivers/s390/block/dasd_int.h
+++ b/drivers/s390/block/dasd_int.h
@@ -646,7 +646,7 @@ struct dasd_block {
 	struct gendisk *gdp;
 	spinlock_t request_queue_lock;
 	struct blk_mq_tag_set tag_set;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	atomic_t open_count;
 
 	unsigned long blocks;	   /* size of volume in blocks */
diff --git a/drivers/s390/block/dasd_ioctl.c b/drivers/s390/block/dasd_ioctl.c
index d55862605b82..61b9675e2a67 100644
--- a/drivers/s390/block/dasd_ioctl.c
+++ b/drivers/s390/block/dasd_ioctl.c
@@ -537,7 +537,7 @@ static int __dasd_ioctl_information(struct dasd_block *block,
 	 * This must be hidden from user-space.
 	 */
 	dasd_info->open_count = atomic_read(&block->open_count);
-	if (!block->bdev)
+	if (!block->bdev_handle)
 		dasd_info->open_count++;
 
 	/*
-- 
2.35.3

[PATCH 15/29] scsi: target: Convert to bdev_open_by_path()

[Jan Kara]

Convert iblock and pscsi drivers to use bdev_open_by_path() and pass the
handle around.

CC: target-devel@vger.kernel.org
CC: linux-scsi@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 drivers/target/target_core_iblock.c | 19 +++++++++++--------
 drivers/target/target_core_iblock.h |  1 +
 drivers/target/target_core_pscsi.c  | 26 +++++++++++++-------------
 drivers/target/target_core_pscsi.h  |  2 +-
 4 files changed, 26 insertions(+), 22 deletions(-)

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 3d1b511ea284..3695a9f8d8a5 100644
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -91,7 +91,8 @@ static int iblock_configure_device(struct se_device *dev)
 {
 	struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 	struct request_queue *q;
-	struct block_device *bd = NULL;
+	struct bdev_handle *bdev_handle;
+	struct block_device *bd;
 	struct blk_integrity *bi;
 	blk_mode_t mode = BLK_OPEN_READ;
 	unsigned int max_write_zeroes_sectors;
@@ -116,12 +117,14 @@ static int iblock_configure_device(struct se_device *dev)
 	else
 		dev->dev_flags |= DF_READ_ONLY;
 
-	bd = blkdev_get_by_path(ib_dev->ibd_udev_path, mode, ib_dev, NULL);
-	if (IS_ERR(bd)) {
-		ret = PTR_ERR(bd);
+	bdev_handle = bdev_open_by_path(ib_dev->ibd_udev_path, mode, ib_dev,
+					NULL);
+	if (IS_ERR(bdev_handle)) {
+		ret = PTR_ERR(bdev_handle);
 		goto out_free_bioset;
 	}
-	ib_dev->ibd_bd = bd;
+	ib_dev->ibd_bdev_handle = bdev_handle;
+	ib_dev->ibd_bd = bd = bdev_handle->bdev;
 
 	q = bdev_get_queue(bd);
 
@@ -177,7 +180,7 @@ static int iblock_configure_device(struct se_device *dev)
 	return 0;
 
 out_blkdev_put:
-	blkdev_put(ib_dev->ibd_bd, ib_dev);
+	bdev_release(ib_dev->ibd_bdev_handle);
 out_free_bioset:
 	bioset_exit(&ib_dev->ibd_bio_set);
 out:
@@ -202,8 +205,8 @@ static void iblock_destroy_device(struct se_device *dev)
 {
 	struct iblock_dev *ib_dev = IBLOCK_DEV(dev);
 
-	if (ib_dev->ibd_bd != NULL)
-		blkdev_put(ib_dev->ibd_bd, ib_dev);
+	if (ib_dev->ibd_bdev_handle)
+		bdev_release(ib_dev->ibd_bdev_handle);
 	bioset_exit(&ib_dev->ibd_bio_set);
 }
 
diff --git a/drivers/target/target_core_iblock.h b/drivers/target/target_core_iblock.h
index 8c55375d2f75..683f9a55945b 100644
--- a/drivers/target/target_core_iblock.h
+++ b/drivers/target/target_core_iblock.h
@@ -32,6 +32,7 @@ struct iblock_dev {
 	u32	ibd_flags;
 	struct bio_set	ibd_bio_set;
 	struct block_device *ibd_bd;
+	struct bdev_handle *ibd_bdev_handle;
 	bool ibd_readonly;
 	struct iblock_dev_plug *ibd_plug;
 } ____cacheline_aligned;
diff --git a/drivers/target/target_core_pscsi.c b/drivers/target/target_core_pscsi.c
index 0d4f09693ef4..41b7489d37ce 100644
--- a/drivers/target/target_core_pscsi.c
+++ b/drivers/target/target_core_pscsi.c
@@ -352,7 +352,7 @@ static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 	struct pscsi_hba_virt *phv = dev->se_hba->hba_ptr;
 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 	struct Scsi_Host *sh = sd->host;
-	struct block_device *bd;
+	struct bdev_handle *bdev_handle;
 	int ret;
 
 	if (scsi_device_get(sd)) {
@@ -366,18 +366,18 @@ static int pscsi_create_type_disk(struct se_device *dev, struct scsi_device *sd)
 	 * Claim exclusive struct block_device access to struct scsi_device
 	 * for TYPE_DISK and TYPE_ZBC using supplied udev_path
 	 */
-	bd = blkdev_get_by_path(dev->udev_path, BLK_OPEN_WRITE | BLK_OPEN_READ,
-				pdv, NULL);
-	if (IS_ERR(bd)) {
-		pr_err("pSCSI: blkdev_get_by_path() failed\n");
+	bdev_handle = bdev_open_by_path(dev->udev_path,
+				BLK_OPEN_WRITE | BLK_OPEN_READ, pdv, NULL);
+	if (IS_ERR(bdev_handle)) {
+		pr_err("pSCSI: bdev_open_by_path() failed\n");
 		scsi_device_put(sd);
-		return PTR_ERR(bd);
+		return PTR_ERR(bdev_handle);
 	}
-	pdv->pdv_bd = bd;
+	pdv->pdv_bdev_handle = bdev_handle;
 
 	ret = pscsi_add_device_to_list(dev, sd);
 	if (ret) {
-		blkdev_put(pdv->pdv_bd, pdv);
+		bdev_release(bdev_handle);
 		scsi_device_put(sd);
 		return ret;
 	}
@@ -564,9 +564,9 @@ static void pscsi_destroy_device(struct se_device *dev)
 		 * from pscsi_create_type_disk()
 		 */
 		if ((sd->type == TYPE_DISK || sd->type == TYPE_ZBC) &&
-		    pdv->pdv_bd) {
-			blkdev_put(pdv->pdv_bd, pdv);
-			pdv->pdv_bd = NULL;
+		    pdv->pdv_bdev_handle) {
+			bdev_release(pdv->pdv_bdev_handle);
+			pdv->pdv_bdev_handle = NULL;
 		}
 		/*
 		 * For HBA mode PHV_LLD_SCSI_HOST_NO, release the reference
@@ -994,8 +994,8 @@ static sector_t pscsi_get_blocks(struct se_device *dev)
 {
 	struct pscsi_dev_virt *pdv = PSCSI_DEV(dev);
 
-	if (pdv->pdv_bd)
-		return bdev_nr_sectors(pdv->pdv_bd);
+	if (pdv->pdv_bdev_handle)
+		return bdev_nr_sectors(pdv->pdv_bdev_handle->bdev);
 	return 0;
 }
 
diff --git a/drivers/target/target_core_pscsi.h b/drivers/target/target_core_pscsi.h
index 23d9a6e340d4..b0a3ef136592 100644
--- a/drivers/target/target_core_pscsi.h
+++ b/drivers/target/target_core_pscsi.h
@@ -37,7 +37,7 @@ struct pscsi_dev_virt {
 	int	pdv_channel_id;
 	int	pdv_target_id;
 	int	pdv_lun_id;
-	struct block_device *pdv_bd;
+	struct bdev_handle *pdv_bdev_handle;
 	struct scsi_device *pdv_sd;
 	struct Scsi_Host *pdv_lld_host;
 } ____cacheline_aligned;
-- 
2.35.3

[PATCH 16/29] PM: hibernate: Convert to bdev_open_by_dev()

[Jan Kara]

Convert hibernation code to use bdev_open_by_dev().

CC: linux-pm@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 kernel/power/swap.c | 31 ++++++++++++++++---------------
 1 file changed, 16 insertions(+), 15 deletions(-)

diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index f6ebcd00c410..b475bee282ff 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -222,7 +222,7 @@ int swsusp_swap_in_use(void)
  */
 
 static unsigned short root_swap = 0xffff;
-static struct block_device *hib_resume_bdev;
+static struct bdev_handle *hib_resume_bdev_handle;
 
 struct hib_bio_batch {
 	atomic_t		count;
@@ -276,7 +276,8 @@ static int hib_submit_io(blk_opf_t opf, pgoff_t page_off, void *addr,
 	struct bio *bio;
 	int error = 0;
 
-	bio = bio_alloc(hib_resume_bdev, 1, opf, GFP_NOIO | __GFP_HIGH);
+	bio = bio_alloc(hib_resume_bdev_handle->bdev, 1, opf,
+			GFP_NOIO | __GFP_HIGH);
 	bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
 
 	if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
@@ -356,14 +357,14 @@ static int swsusp_swap_check(void)
 		return res;
 	root_swap = res;
 
-	hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
+	hib_resume_bdev_handle = bdev_open_by_dev(swsusp_resume_device,
 			BLK_OPEN_WRITE, NULL, NULL);
-	if (IS_ERR(hib_resume_bdev))
-		return PTR_ERR(hib_resume_bdev);
+	if (IS_ERR(hib_resume_bdev_handle))
+		return PTR_ERR(hib_resume_bdev_handle);
 
-	res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
+	res = set_blocksize(hib_resume_bdev_handle->bdev, PAGE_SIZE);
 	if (res < 0)
-		blkdev_put(hib_resume_bdev, NULL);
+		bdev_release(hib_resume_bdev_handle);
 
 	return res;
 }
@@ -1521,10 +1522,10 @@ int swsusp_check(bool snapshot_test)
 	void *holder = snapshot_test ? &swsusp_holder : NULL;
 	int error;
 
-	hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, BLK_OPEN_READ,
-					    holder, NULL);
-	if (!IS_ERR(hib_resume_bdev)) {
-		set_blocksize(hib_resume_bdev, PAGE_SIZE);
+	hib_resume_bdev_handle = bdev_open_by_dev(swsusp_resume_device,
+				BLK_OPEN_READ, holder, NULL);
+	if (!IS_ERR(hib_resume_bdev_handle)) {
+		set_blocksize(hib_resume_bdev_handle->bdev, PAGE_SIZE);
 		clear_page(swsusp_header);
 		error = hib_submit_io(REQ_OP_READ, swsusp_resume_block,
 					swsusp_header, NULL);
@@ -1549,11 +1550,11 @@ int swsusp_check(bool snapshot_test)
 
 put:
 		if (error)
-			blkdev_put(hib_resume_bdev, holder);
+			bdev_release(hib_resume_bdev_handle);
 		else
 			pr_debug("Image signature found, resuming\n");
 	} else {
-		error = PTR_ERR(hib_resume_bdev);
+		error = PTR_ERR(hib_resume_bdev_handle);
 	}
 
 	if (error)
@@ -1568,12 +1569,12 @@ int swsusp_check(bool snapshot_test)
 
 void swsusp_close(bool snapshot_test)
 {
-	if (IS_ERR(hib_resume_bdev)) {
+	if (IS_ERR(hib_resume_bdev_handle)) {
 		pr_debug("Image device not initialised\n");
 		return;
 	}
 
-	blkdev_put(hib_resume_bdev, snapshot_test ? &swsusp_holder : NULL);
+	bdev_release(hib_resume_bdev_handle);
 }
 
 /**
-- 
2.35.3

[PATCH 17/29] PM: hibernate: Drop unused snapshot_test argument

[Jan Kara]

snapshot_test argument is now unused in swsusp_close() and
load_image_and_restore(). Drop it

CC: linux-pm@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 kernel/power/hibernate.c | 14 +++++++-------
 kernel/power/power.h     |  2 +-
 kernel/power/swap.c      |  6 +++---
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index e1b4bfa938dd..6abeec0ae084 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -684,7 +684,7 @@ static void power_down(void)
 		cpu_relax();
 }
 
-static int load_image_and_restore(bool snapshot_test)
+static int load_image_and_restore(void)
 {
 	int error;
 	unsigned int flags;
@@ -694,12 +694,12 @@ static int load_image_and_restore(bool snapshot_test)
 	lock_device_hotplug();
 	error = create_basic_memory_bitmaps();
 	if (error) {
-		swsusp_close(snapshot_test);
+		swsusp_close();
 		goto Unlock;
 	}
 
 	error = swsusp_read(&flags);
-	swsusp_close(snapshot_test);
+	swsusp_close();
 	if (!error)
 		error = hibernation_restore(flags & SF_PLATFORM_MODE);
 
@@ -788,7 +788,7 @@ int hibernate(void)
 		pm_pr_dbg("Checking hibernation image\n");
 		error = swsusp_check(snapshot_test);
 		if (!error)
-			error = load_image_and_restore(snapshot_test);
+			error = load_image_and_restore();
 	}
 	thaw_processes();
 
@@ -952,7 +952,7 @@ static int software_resume(void)
 	/* The snapshot device should not be opened while we're running */
 	if (!hibernate_acquire()) {
 		error = -EBUSY;
-		swsusp_close(false);
+		swsusp_close();
 		goto Unlock;
 	}
 
@@ -973,7 +973,7 @@ static int software_resume(void)
 		goto Close_Finish;
 	}
 
-	error = load_image_and_restore(false);
+	error = load_image_and_restore();
 	thaw_processes();
  Finish:
 	pm_notifier_call_chain(PM_POST_RESTORE);
@@ -987,7 +987,7 @@ static int software_resume(void)
 	pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
 	return error;
  Close_Finish:
-	swsusp_close(false);
+	swsusp_close();
 	goto Finish;
 }
 
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 46eb14dc50c3..bebf049a51c1 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -172,7 +172,7 @@ int swsusp_check(bool snapshot_test);
 extern void swsusp_free(void);
 extern int swsusp_read(unsigned int *flags_p);
 extern int swsusp_write(unsigned int flags);
-void swsusp_close(bool snapshot_test);
+void swsusp_close(void);
 #ifdef CONFIG_SUSPEND
 extern int swsusp_unmark(void);
 #endif
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index b475bee282ff..17e0dad5008e 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -444,7 +444,7 @@ static int get_swap_writer(struct swap_map_handle *handle)
 err_rel:
 	release_swap_writer(handle);
 err_close:
-	swsusp_close(false);
+	swsusp_close();
 	return ret;
 }
 
@@ -509,7 +509,7 @@ static int swap_writer_finish(struct swap_map_handle *handle,
 	if (error)
 		free_all_swap_pages(root_swap);
 	release_swap_writer(handle);
-	swsusp_close(false);
+	swsusp_close();
 
 	return error;
 }
@@ -1567,7 +1567,7 @@ int swsusp_check(bool snapshot_test)
  *	swsusp_close - close swap device.
  */
 
-void swsusp_close(bool snapshot_test)
+void swsusp_close(void)
 {
 	if (IS_ERR(hib_resume_bdev_handle)) {
 		pr_debug("Image device not initialised\n");
-- 
2.35.3

[PATCH 18/29] mm/swap: Convert to use bdev_open_by_dev()

[Jan Kara]

Convert swapping code to use bdev_open_by_dev() and pass the handle
around.

CC: linux-mm@kvack.org
CC: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 include/linux/swap.h |  1 +
 mm/swapfile.c        | 23 ++++++++++++-----------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/include/linux/swap.h b/include/linux/swap.h
index 456546443f1f..62334f8d4932 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -298,6 +298,7 @@ struct swap_info_struct {
 	unsigned int __percpu *cluster_next_cpu; /*percpu index for next allocation */
 	struct percpu_cluster __percpu *percpu_cluster; /* per cpu's swap location */
 	struct rb_root swap_extent_root;/* root of the swap extent rbtree */
+	struct bdev_handle *bdev_handle;/* open handle of the bdev */
 	struct block_device *bdev;	/* swap device or bdev of swap file */
 	struct file *swap_file;		/* seldom referenced */
 	unsigned int old_block_size;	/* seldom referenced */
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 8e6dde68b389..621428ee6895 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -2526,11 +2526,10 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile)
 	exit_swap_address_space(p->type);
 
 	inode = mapping->host;
-	if (S_ISBLK(inode->i_mode)) {
-		struct block_device *bdev = I_BDEV(inode);
-
-		set_blocksize(bdev, old_block_size);
-		blkdev_put(bdev, p);
+	if (p->bdev_handle) {
+		set_blocksize(p->bdev, old_block_size);
+		bdev_release(p->bdev_handle);
+		p->bdev_handle = NULL;
 	}
 
 	inode_lock(inode);
@@ -2760,13 +2759,14 @@ static int claim_swapfile(struct swap_info_struct *p, struct inode *inode)
 	int error;
 
 	if (S_ISBLK(inode->i_mode)) {
-		p->bdev = blkdev_get_by_dev(inode->i_rdev,
+		p->bdev_handle = bdev_open_by_dev(inode->i_rdev,
 				BLK_OPEN_READ | BLK_OPEN_WRITE, p, NULL);
-		if (IS_ERR(p->bdev)) {
-			error = PTR_ERR(p->bdev);
-			p->bdev = NULL;
+		if (IS_ERR(p->bdev_handle)) {
+			error = PTR_ERR(p->bdev_handle);
+			p->bdev_handle = NULL;
 			return error;
 		}
+		p->bdev = p->bdev_handle->bdev;
 		p->old_block_size = block_size(p->bdev);
 		error = set_blocksize(p->bdev, PAGE_SIZE);
 		if (error < 0)
@@ -3210,9 +3210,10 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags)
 	p->percpu_cluster = NULL;
 	free_percpu(p->cluster_next_cpu);
 	p->cluster_next_cpu = NULL;
-	if (inode && S_ISBLK(inode->i_mode) && p->bdev) {
+	if (p->bdev_handle) {
 		set_blocksize(p->bdev, p->old_block_size);
-		blkdev_put(p->bdev, p);
+		bdev_release(p->bdev_handle);
+		p->bdev_handle = NULL;
 	}
 	inode = NULL;
 	destroy_swap_extents(p);
-- 
2.35.3

[PATCH 19/29] fs: Convert to bdev_open_by_dev()

[Jan Kara]

Convert mount code to use bdev_open_by_dev() and propagate the handle
around to bdev_release().

Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/super.c         | 15 +++++++++------
 include/linux/fs.h |  1 +
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/fs/super.c b/fs/super.c
index 71fe297a7e90..030e897c2c68 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1270,14 +1270,16 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 		struct fs_context *fc)
 {
 	blk_mode_t mode = sb_open_mode(sb_flags);
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 
-	bdev = blkdev_get_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
+	if (IS_ERR(bdev_handle)) {
 		if (fc)
 			errorf(fc, "%s: Can't open blockdev", fc->source);
-		return PTR_ERR(bdev);
+		return PTR_ERR(bdev_handle);
 	}
+	bdev = bdev_handle->bdev;
 
 	/*
 	 * This really should be in blkdev_get_by_dev, but right now can't due
@@ -1285,7 +1287,7 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 	 * writable from userspace even for a read-only block device.
 	 */
 	if ((mode & BLK_OPEN_WRITE) && bdev_read_only(bdev)) {
-		blkdev_put(bdev, sb);
+		bdev_release(bdev_handle);
 		return -EACCES;
 	}
 
@@ -1301,10 +1303,11 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 		mutex_unlock(&bdev->bd_fsfreeze_mutex);
 		if (fc)
 			warnf(fc, "%pg: Can't mount, blockdev is frozen", bdev);
-		blkdev_put(bdev, sb);
+		bdev_release(bdev_handle);
 		return -EBUSY;
 	}
 	spin_lock(&sb_lock);
+	sb->s_bdev_handle = bdev_handle;
 	sb->s_bdev = bdev;
 	sb->s_bdi = bdi_get(bdev->bd_disk->bdi);
 	if (bdev_stable_writes(bdev))
@@ -1438,7 +1441,7 @@ void kill_block_super(struct super_block *sb)
 	generic_shutdown_super(sb);
 	if (bdev) {
 		sync_blockdev(bdev);
-		blkdev_put(bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 }
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 234ad85a28b5..a77a20955d91 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1187,6 +1187,7 @@ struct super_block {
 	struct hlist_bl_head	s_roots;	/* alternate root dentries for NFS */
 	struct list_head	s_mounts;	/* list of mounts; _not_ for fs use */
 	struct block_device	*s_bdev;
+	struct bdev_handle	*s_bdev_handle;
 	struct backing_dev_info *s_bdi;
 	struct mtd_info		*s_mtd;
 	struct hlist_node	s_instances;
-- 
2.35.3

[PATCH 20/29] btrfs: Convert to bdev_open_by_path()

[Jan Kara]

Convert btrfs to use bdev_open_by_path() and pass the handle around.  We
also drop the holder from struct btrfs_device as it is now not needed
anymore.

CC: David Sterba <dsterba@suse.com>
CC: linux-btrfs@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/btrfs/dev-replace.c |  14 +++---
 fs/btrfs/ioctl.c       |  18 +++----
 fs/btrfs/volumes.c     | 107 +++++++++++++++++++++--------------------
 fs/btrfs/volumes.h     |   6 +--
 4 files changed, 73 insertions(+), 72 deletions(-)

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 5f10965fd72b..fec013c5f26c 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -247,6 +247,7 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 {
 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 	struct btrfs_device *device;
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 	u64 devid = BTRFS_DEV_REPLACE_DEVID;
 	int ret = 0;
@@ -257,12 +258,13 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 		return -EINVAL;
 	}
 
-	bdev = blkdev_get_by_path(device_path, BLK_OPEN_WRITE,
-				  fs_info->bdev_holder, NULL);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_path(device_path, BLK_OPEN_WRITE,
+					fs_info->bdev_holder, NULL);
+	if (IS_ERR(bdev_handle)) {
 		btrfs_err(fs_info, "target device %s is invalid!", device_path);
-		return PTR_ERR(bdev);
+		return PTR_ERR(bdev_handle);
 	}
+	bdev = bdev_handle->bdev;
 
 	if (!btrfs_check_device_zone_type(fs_info, bdev)) {
 		btrfs_err(fs_info,
@@ -313,9 +315,9 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 	device->commit_bytes_used = device->bytes_used;
 	device->fs_info = fs_info;
 	device->bdev = bdev;
+	device->bdev_handle = bdev_handle;
 	set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
 	set_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
-	device->holder = fs_info->bdev_holder;
 	device->dev_stats_valid = 1;
 	set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE);
 	device->fs_devices = fs_devices;
@@ -334,7 +336,7 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 	return 0;
 
 error:
-	blkdev_put(bdev, fs_info->bdev_holder);
+	bdev_release(bdev_handle);
 	return ret;
 }
 
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a18ee7b5a166..b4074191fcc7 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -2670,8 +2670,7 @@ static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
 	struct inode *inode = file_inode(file);
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_ioctl_vol_args_v2 *vol_args;
-	struct block_device *bdev = NULL;
-	void *holder;
+	struct bdev_handle *bdev_handle = NULL;
 	int ret;
 	bool cancel = false;
 
@@ -2708,7 +2707,7 @@ static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
 		goto err_drop;
 
 	/* Exclusive operation is now claimed */
-	ret = btrfs_rm_device(fs_info, &args, &bdev, &holder);
+	ret = btrfs_rm_device(fs_info, &args, &bdev_handle);
 
 	btrfs_exclop_finish(fs_info);
 
@@ -2722,8 +2721,8 @@ static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
 	}
 err_drop:
 	mnt_drop_write_file(file);
-	if (bdev)
-		blkdev_put(bdev, holder);
+	if (bdev_handle)
+		bdev_release(bdev_handle);
 out:
 	btrfs_put_dev_args_from_path(&args);
 	kfree(vol_args);
@@ -2736,8 +2735,7 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
 	struct inode *inode = file_inode(file);
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_ioctl_vol_args *vol_args;
-	struct block_device *bdev = NULL;
-	void *holder;
+	struct bdev_handle *bdev_handle = NULL;
 	int ret;
 	bool cancel = false;
 
@@ -2764,15 +2762,15 @@ static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
 	ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
 					   cancel);
 	if (ret == 0) {
-		ret = btrfs_rm_device(fs_info, &args, &bdev, &holder);
+		ret = btrfs_rm_device(fs_info, &args, &bdev_handle);
 		if (!ret)
 			btrfs_info(fs_info, "disk deleted %s", vol_args->name);
 		btrfs_exclop_finish(fs_info);
 	}
 
 	mnt_drop_write_file(file);
-	if (bdev)
-		blkdev_put(bdev, holder);
+	if (bdev_handle)
+		bdev_release(bdev_handle);
 out:
 	btrfs_put_dev_args_from_path(&args);
 	kfree(vol_args);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index e33ed9810f07..465d9b7252b4 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -511,37 +511,39 @@ static struct btrfs_fs_devices *find_fsid_with_metadata_uuid(
 
 static int
 btrfs_get_bdev_and_sb(const char *device_path, blk_mode_t flags, void *holder,
-		      int flush, struct block_device **bdev,
+		      int flush, struct bdev_handle **bdev_handle,
 		      struct btrfs_super_block **disk_super)
 {
+	struct block_device *bdev;
 	int ret;
 
-	*bdev = blkdev_get_by_path(device_path, flags, holder, NULL);
+	*bdev_handle = bdev_open_by_path(device_path, flags, holder, NULL);
 
-	if (IS_ERR(*bdev)) {
-		ret = PTR_ERR(*bdev);
+	if (IS_ERR(*bdev_handle)) {
+		ret = PTR_ERR(*bdev_handle);
 		goto error;
 	}
+	bdev = (*bdev_handle)->bdev;
 
 	if (flush)
-		sync_blockdev(*bdev);
-	ret = set_blocksize(*bdev, BTRFS_BDEV_BLOCKSIZE);
+		sync_blockdev(bdev);
+	ret = set_blocksize(bdev, BTRFS_BDEV_BLOCKSIZE);
 	if (ret) {
-		blkdev_put(*bdev, holder);
+		bdev_release(*bdev_handle);
 		goto error;
 	}
-	invalidate_bdev(*bdev);
-	*disk_super = btrfs_read_dev_super(*bdev);
+	invalidate_bdev(bdev);
+	*disk_super = btrfs_read_dev_super(bdev);
 	if (IS_ERR(*disk_super)) {
 		ret = PTR_ERR(*disk_super);
-		blkdev_put(*bdev, holder);
+		bdev_release(*bdev_handle);
 		goto error;
 	}
 
 	return 0;
 
 error:
-	*bdev = NULL;
+	*bdev_handle = NULL;
 	return ret;
 }
 
@@ -613,7 +615,7 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
 			struct btrfs_device *device, blk_mode_t flags,
 			void *holder)
 {
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	struct btrfs_super_block *disk_super;
 	u64 devid;
 	int ret;
@@ -624,7 +626,7 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
 		return -EINVAL;
 
 	ret = btrfs_get_bdev_and_sb(device->name->str, flags, holder, 1,
-				    &bdev, &disk_super);
+				    &bdev_handle, &disk_super);
 	if (ret)
 		return ret;
 
@@ -648,21 +650,21 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
 		clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
 		fs_devices->seeding = true;
 	} else {
-		if (bdev_read_only(bdev))
+		if (bdev_read_only(bdev_handle->bdev))
 			clear_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
 		else
 			set_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state);
 	}
 
-	if (!bdev_nonrot(bdev))
+	if (!bdev_nonrot(bdev_handle->bdev))
 		fs_devices->rotating = true;
 
-	if (bdev_max_discard_sectors(bdev))
+	if (bdev_max_discard_sectors(bdev_handle->bdev))
 		fs_devices->discardable = true;
 
-	device->bdev = bdev;
+	device->bdev_handle = bdev_handle;
+	device->bdev = bdev_handle->bdev;
 	clear_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
-	device->holder = holder;
 
 	fs_devices->open_devices++;
 	if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state) &&
@@ -676,7 +678,7 @@ static int btrfs_open_one_device(struct btrfs_fs_devices *fs_devices,
 
 error_free_page:
 	btrfs_release_disk_super(disk_super);
-	blkdev_put(bdev, holder);
+	bdev_release(bdev_handle);
 
 	return -EINVAL;
 }
@@ -1066,9 +1068,10 @@ static void __btrfs_free_extra_devids(struct btrfs_fs_devices *fs_devices,
 		if (device->devid == BTRFS_DEV_REPLACE_DEVID)
 			continue;
 
-		if (device->bdev) {
-			blkdev_put(device->bdev, device->holder);
+		if (device->bdev_handle) {
+			bdev_release(device->bdev_handle);
 			device->bdev = NULL;
+			device->bdev_handle = NULL;
 			fs_devices->open_devices--;
 		}
 		if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
@@ -1113,7 +1116,7 @@ static void btrfs_close_bdev(struct btrfs_device *device)
 		invalidate_bdev(device->bdev);
 	}
 
-	blkdev_put(device->bdev, device->holder);
+	bdev_release(device->bdev_handle);
 }
 
 static void btrfs_close_one_device(struct btrfs_device *device)
@@ -1361,7 +1364,7 @@ struct btrfs_device *btrfs_scan_one_device(const char *path)
 	struct btrfs_super_block *disk_super;
 	bool new_device_added = false;
 	struct btrfs_device *device = NULL;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	u64 bytenr, bytenr_orig;
 	int ret;
 
@@ -1384,18 +1387,19 @@ struct btrfs_device *btrfs_scan_one_device(const char *path)
 	 * values temporarily, as the device paths of the fsid are the only
 	 * required information for assembling the volume.
 	 */
-	bdev = blkdev_get_by_path(path, BLK_OPEN_READ, NULL, NULL);
-	if (IS_ERR(bdev))
-		return ERR_CAST(bdev);
+	bdev_handle = bdev_open_by_path(path, BLK_OPEN_READ, NULL, NULL);
+	if (IS_ERR(bdev_handle))
+		return ERR_CAST(bdev_handle);
 
 	bytenr_orig = btrfs_sb_offset(0);
-	ret = btrfs_sb_log_location_bdev(bdev, 0, READ, &bytenr);
+	ret = btrfs_sb_log_location_bdev(bdev_handle->bdev, 0, READ, &bytenr);
 	if (ret) {
 		device = ERR_PTR(ret);
 		goto error_bdev_put;
 	}
 
-	disk_super = btrfs_read_disk_super(bdev, bytenr, bytenr_orig);
+	disk_super = btrfs_read_disk_super(bdev_handle->bdev, bytenr,
+					   bytenr_orig);
 	if (IS_ERR(disk_super)) {
 		device = ERR_CAST(disk_super);
 		goto error_bdev_put;
@@ -1408,7 +1412,7 @@ struct btrfs_device *btrfs_scan_one_device(const char *path)
 	btrfs_release_disk_super(disk_super);
 
 error_bdev_put:
-	blkdev_put(bdev, NULL);
+	bdev_release(bdev_handle);
 
 	return device;
 }
@@ -2093,7 +2097,7 @@ void btrfs_scratch_superblocks(struct btrfs_fs_info *fs_info,
 
 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 		    struct btrfs_dev_lookup_args *args,
-		    struct block_device **bdev, void **holder)
+		    struct bdev_handle **bdev_handle)
 {
 	struct btrfs_trans_handle *trans;
 	struct btrfs_device *device;
@@ -2202,7 +2206,7 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 
 	btrfs_assign_next_active_device(device, NULL);
 
-	if (device->bdev) {
+	if (device->bdev_handle) {
 		cur_devices->open_devices--;
 		/* remove sysfs entry */
 		btrfs_sysfs_remove_device(device);
@@ -2218,9 +2222,9 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 	 * free the device.
 	 *
 	 * We cannot call btrfs_close_bdev() here because we're holding the sb
-	 * write lock, and blkdev_put() will pull in the ->open_mutex on the
-	 * block device and it's dependencies.  Instead just flush the device
-	 * and let the caller do the final blkdev_put.
+	 * write lock, and bdev_release() will pull in the ->open_mutex on
+	 * the block device and it's dependencies.  Instead just flush the
+	 * device and let the caller do the final bdev_release.
 	 */
 	if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
 		btrfs_scratch_superblocks(fs_info, device->bdev,
@@ -2231,8 +2235,7 @@ int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 		}
 	}
 
-	*bdev = device->bdev;
-	*holder = device->holder;
+	*bdev_handle = device->bdev_handle;
 	synchronize_rcu();
 	btrfs_free_device(device);
 
@@ -2369,7 +2372,7 @@ int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
 				 const char *path)
 {
 	struct btrfs_super_block *disk_super;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	int ret;
 
 	if (!path || !path[0])
@@ -2387,7 +2390,7 @@ int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
 	}
 
 	ret = btrfs_get_bdev_and_sb(path, BLK_OPEN_READ, NULL, 0,
-				    &bdev, &disk_super);
+				    &bdev_handle, &disk_super);
 	if (ret) {
 		btrfs_put_dev_args_from_path(args);
 		return ret;
@@ -2400,7 +2403,7 @@ int btrfs_get_dev_args_from_path(struct btrfs_fs_info *fs_info,
 	else
 		memcpy(args->fsid, disk_super->fsid, BTRFS_FSID_SIZE);
 	btrfs_release_disk_super(disk_super);
-	blkdev_put(bdev, NULL);
+	bdev_release(bdev_handle);
 	return 0;
 }
 
@@ -2620,7 +2623,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 	struct btrfs_root *root = fs_info->dev_root;
 	struct btrfs_trans_handle *trans;
 	struct btrfs_device *device;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	struct super_block *sb = fs_info->sb;
 	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
 	struct btrfs_fs_devices *seed_devices = NULL;
@@ -2633,12 +2636,12 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 	if (sb_rdonly(sb) && !fs_devices->seeding)
 		return -EROFS;
 
-	bdev = blkdev_get_by_path(device_path, BLK_OPEN_WRITE,
-				  fs_info->bdev_holder, NULL);
-	if (IS_ERR(bdev))
-		return PTR_ERR(bdev);
+	bdev_handle = bdev_open_by_path(device_path, BLK_OPEN_WRITE,
+					fs_info->bdev_holder, NULL);
+	if (IS_ERR(bdev_handle))
+		return PTR_ERR(bdev_handle);
 
-	if (!btrfs_check_device_zone_type(fs_info, bdev)) {
+	if (!btrfs_check_device_zone_type(fs_info, bdev_handle->bdev)) {
 		ret = -EINVAL;
 		goto error;
 	}
@@ -2650,11 +2653,11 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 		locked = true;
 	}
 
-	sync_blockdev(bdev);
+	sync_blockdev(bdev_handle->bdev);
 
 	rcu_read_lock();
 	list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
-		if (device->bdev == bdev) {
+		if (device->bdev == bdev_handle->bdev) {
 			ret = -EEXIST;
 			rcu_read_unlock();
 			goto error;
@@ -2670,7 +2673,8 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 	}
 
 	device->fs_info = fs_info;
-	device->bdev = bdev;
+	device->bdev_handle = bdev_handle;
+	device->bdev = bdev_handle->bdev;
 	ret = lookup_bdev(device_path, &device->devt);
 	if (ret)
 		goto error_free_device;
@@ -2691,12 +2695,11 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 	device->io_align = fs_info->sectorsize;
 	device->sector_size = fs_info->sectorsize;
 	device->total_bytes =
-		round_down(bdev_nr_bytes(bdev), fs_info->sectorsize);
+		round_down(bdev_nr_bytes(device->bdev), fs_info->sectorsize);
 	device->disk_total_bytes = device->total_bytes;
 	device->commit_total_bytes = device->total_bytes;
 	set_bit(BTRFS_DEV_STATE_IN_FS_METADATA, &device->dev_state);
 	clear_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state);
-	device->holder = fs_info->bdev_holder;
 	device->dev_stats_valid = 1;
 	set_blocksize(device->bdev, BTRFS_BDEV_BLOCKSIZE);
 
@@ -2732,7 +2735,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 
 	atomic64_add(device->total_bytes, &fs_info->free_chunk_space);
 
-	if (!bdev_nonrot(bdev))
+	if (!bdev_nonrot(device->bdev))
 		fs_devices->rotating = true;
 
 	orig_super_total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
@@ -2854,7 +2857,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 error_free_device:
 	btrfs_free_device(device);
 error:
-	blkdev_put(bdev, fs_info->bdev_holder);
+	bdev_release(bdev_handle);
 	if (locked) {
 		mutex_unlock(&uuid_mutex);
 		up_write(&sb->s_umount);
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h
index 824161c6dd06..ad00017798b1 100644
--- a/fs/btrfs/volumes.h
+++ b/fs/btrfs/volumes.h
@@ -90,13 +90,11 @@ struct btrfs_device {
 
 	u64 generation;
 
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 
 	struct btrfs_zoned_device_info *zone_info;
 
-	/* block device holder for blkdev_get/put */
-	void *holder;
-
 	/*
 	 * Device's major-minor number. Must be set even if the device is not
 	 * opened (bdev == NULL), unless the device is missing.
@@ -629,7 +627,7 @@ struct btrfs_device *btrfs_alloc_device(struct btrfs_fs_info *fs_info,
 void btrfs_put_dev_args_from_path(struct btrfs_dev_lookup_args *args);
 int btrfs_rm_device(struct btrfs_fs_info *fs_info,
 		    struct btrfs_dev_lookup_args *args,
-		    struct block_device **bdev, void **holder);
+		    struct bdev_handle **bdev_handle);
 void __exit btrfs_cleanup_fs_uuids(void);
 int btrfs_num_copies(struct btrfs_fs_info *fs_info, u64 logical, u64 len);
 int btrfs_grow_device(struct btrfs_trans_handle *trans,
-- 
2.35.3

[PATCH 21/29] erofs: Convert to use bdev_open_by_path()

[Jan Kara]

Convert erofs to use bdev_open_by_path() and pass the handle around.

CC: Gao Xiang <xiang@kernel.org>
CC: Chao Yu <chao@kernel.org>
CC: linux-erofs@lists.ozlabs.org
Acked-by: Gao Xiang <hsiangkao@linux.alibaba.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/erofs/data.c     |  4 ++--
 fs/erofs/internal.h |  2 +-
 fs/erofs/super.c    | 20 ++++++++++----------
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/fs/erofs/data.c b/fs/erofs/data.c
index db5e4b7636ec..1fa60cfff267 100644
--- a/fs/erofs/data.c
+++ b/fs/erofs/data.c
@@ -222,7 +222,7 @@ int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *map)
 			up_read(&devs->rwsem);
 			return 0;
 		}
-		map->m_bdev = dif->bdev;
+		map->m_bdev = dif->bdev_handle->bdev;
 		map->m_daxdev = dif->dax_dev;
 		map->m_dax_part_off = dif->dax_part_off;
 		map->m_fscache = dif->fscache;
@@ -240,7 +240,7 @@ int erofs_map_dev(struct super_block *sb, struct erofs_map_dev *map)
 			if (map->m_pa >= startoff &&
 			    map->m_pa < startoff + length) {
 				map->m_pa -= startoff;
-				map->m_bdev = dif->bdev;
+				map->m_bdev = dif->bdev_handle->bdev;
 				map->m_daxdev = dif->dax_dev;
 				map->m_dax_part_off = dif->dax_part_off;
 				map->m_fscache = dif->fscache;
diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h
index 36e32fa542f0..fabd3bb0c194 100644
--- a/fs/erofs/internal.h
+++ b/fs/erofs/internal.h
@@ -47,7 +47,7 @@ typedef u32 erofs_blk_t;
 struct erofs_device_info {
 	char *path;
 	struct erofs_fscache *fscache;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	struct dax_device *dax_dev;
 	u64 dax_part_off;
 
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 9d6a3c6158bd..ce163b456d4a 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -230,7 +230,7 @@ static int erofs_init_device(struct erofs_buf *buf, struct super_block *sb,
 	struct erofs_sb_info *sbi = EROFS_SB(sb);
 	struct erofs_fscache *fscache;
 	struct erofs_deviceslot *dis;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	void *ptr;
 
 	ptr = erofs_read_metabuf(buf, sb, erofs_blknr(sb, *pos), EROFS_KMAP);
@@ -254,13 +254,13 @@ static int erofs_init_device(struct erofs_buf *buf, struct super_block *sb,
 			return PTR_ERR(fscache);
 		dif->fscache = fscache;
 	} else if (!sbi->devs->flatdev) {
-		bdev = blkdev_get_by_path(dif->path, BLK_OPEN_READ, sb->s_type,
-					  NULL);
-		if (IS_ERR(bdev))
-			return PTR_ERR(bdev);
-		dif->bdev = bdev;
-		dif->dax_dev = fs_dax_get_by_bdev(bdev, &dif->dax_part_off,
-						  NULL, NULL);
+		bdev_handle = bdev_open_by_path(dif->path, BLK_OPEN_READ,
+						sb->s_type, NULL);
+		if (IS_ERR(bdev_handle))
+			return PTR_ERR(bdev_handle);
+		dif->bdev_handle = bdev_handle;
+		dif->dax_dev = fs_dax_get_by_bdev(bdev_handle->bdev,
+				&dif->dax_part_off, NULL, NULL);
 	}
 
 	dif->blocks = le32_to_cpu(dis->blocks);
@@ -815,8 +815,8 @@ static int erofs_release_device_info(int id, void *ptr, void *data)
 	struct erofs_device_info *dif = ptr;
 
 	fs_put_dax(dif->dax_dev, NULL);
-	if (dif->bdev)
-		blkdev_put(dif->bdev, &erofs_fs_type);
+	if (dif->bdev_handle)
+		bdev_release(dif->bdev_handle);
 	erofs_fscache_unregister_cookie(dif->fscache);
 	dif->fscache = NULL;
 	kfree(dif->path);
-- 
2.35.3

[PATCH 22/29] ext4: Convert to bdev_open_by_dev()

[Jan Kara]

Convert ext4 to use bdev_open_by_dev() and pass the handle around.

CC: <linux-ext4@vger.kernel.org>
CC: Ted Tso <tytso@mit.edu>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ext4/ext4.h  |  2 +-
 fs/ext4/fsmap.c |  9 +++++----
 fs/ext4/super.c | 40 ++++++++++++++++++++--------------------
 3 files changed, 26 insertions(+), 25 deletions(-)

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 1e2259d9967d..6856e80abf70 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1541,7 +1541,7 @@ struct ext4_sb_info {
 	unsigned long s_commit_interval;
 	u32 s_max_batch_time;
 	u32 s_min_batch_time;
-	struct block_device *s_journal_bdev;
+	struct bdev_handle *s_journal_bdev_handle;
 #ifdef CONFIG_QUOTA
 	/* Names of quota files with journalled quota */
 	char __rcu *s_qf_names[EXT4_MAXQUOTAS];
diff --git a/fs/ext4/fsmap.c b/fs/ext4/fsmap.c
index cdf9bfe10137..11e6f33677a2 100644
--- a/fs/ext4/fsmap.c
+++ b/fs/ext4/fsmap.c
@@ -576,8 +576,9 @@ static bool ext4_getfsmap_is_valid_device(struct super_block *sb,
 	if (fm->fmr_device == 0 || fm->fmr_device == UINT_MAX ||
 	    fm->fmr_device == new_encode_dev(sb->s_bdev->bd_dev))
 		return true;
-	if (EXT4_SB(sb)->s_journal_bdev &&
-	    fm->fmr_device == new_encode_dev(EXT4_SB(sb)->s_journal_bdev->bd_dev))
+	if (EXT4_SB(sb)->s_journal_bdev_handle &&
+	    fm->fmr_device ==
+	    new_encode_dev(EXT4_SB(sb)->s_journal_bdev_handle->bdev->bd_dev))
 		return true;
 	return false;
 }
@@ -647,9 +648,9 @@ int ext4_getfsmap(struct super_block *sb, struct ext4_fsmap_head *head,
 	memset(handlers, 0, sizeof(handlers));
 	handlers[0].gfd_dev = new_encode_dev(sb->s_bdev->bd_dev);
 	handlers[0].gfd_fn = ext4_getfsmap_datadev;
-	if (EXT4_SB(sb)->s_journal_bdev) {
+	if (EXT4_SB(sb)->s_journal_bdev_handle) {
 		handlers[1].gfd_dev = new_encode_dev(
-				EXT4_SB(sb)->s_journal_bdev->bd_dev);
+			EXT4_SB(sb)->s_journal_bdev_handle->bdev->bd_dev);
 		handlers[1].gfd_fn = ext4_getfsmap_logdev;
 	}
 
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 45fd5372bf8a..9ca3665e1b92 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1099,20 +1099,20 @@ void ext4_update_dynamic_rev(struct super_block *sb)
 /*
  * Open the external journal device
  */
-static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
+static struct bdev_handle *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 {
-	struct block_device *bdev;
+	struct bdev_handle *handle;
 
-	bdev = blkdev_get_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE, sb,
-				 &fs_holder_ops);
-	if (IS_ERR(bdev))
+	handle = bdev_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE, sb,
+				  &fs_holder_ops);
+	if (IS_ERR(handle))
 		goto fail;
-	return bdev;
+	return handle;
 
 fail:
 	ext4_msg(sb, KERN_ERR,
 		 "failed to open journal device unknown-block(%u,%u) %ld",
-		 MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
+		 MAJOR(dev), MINOR(dev), PTR_ERR(handle));
 	return NULL;
 }
 
@@ -1121,17 +1121,15 @@ static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
  */
 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 {
-	struct block_device *bdev;
-	bdev = sbi->s_journal_bdev;
-	if (bdev) {
+	if (sbi->s_journal_bdev_handle) {
 		/*
 		 * Invalidate the journal device's buffers.  We don't want them
 		 * floating about in memory - the physical journal device may
 		 * hotswapped, and it breaks the `ro-after' testing code.
 		 */
-		invalidate_bdev(bdev);
-		blkdev_put(bdev, sbi->s_sb);
-		sbi->s_journal_bdev = NULL;
+		invalidate_bdev(sbi->s_journal_bdev_handle->bdev);
+		bdev_release(sbi->s_journal_bdev_handle);
+		sbi->s_journal_bdev_handle = NULL;
 	}
 }
 
@@ -1329,8 +1327,8 @@ static void ext4_put_super(struct super_block *sb)
 
 	sync_blockdev(sb->s_bdev);
 	invalidate_bdev(sb->s_bdev);
-	if (sbi->s_journal_bdev) {
-		sync_blockdev(sbi->s_journal_bdev);
+	if (sbi->s_journal_bdev_handle) {
+		sync_blockdev(sbi->s_journal_bdev_handle->bdev);
 		ext4_blkdev_remove(sbi);
 	}
 
@@ -4218,7 +4216,7 @@ int ext4_calculate_overhead(struct super_block *sb)
 	 * Add the internal journal blocks whether the journal has been
 	 * loaded or not
 	 */
-	if (sbi->s_journal && !sbi->s_journal_bdev)
+	if (sbi->s_journal && !sbi->s_journal_bdev_handle)
 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
 		/* j_inum for internal journal is non-zero */
@@ -5840,17 +5838,19 @@ static journal_t *ext4_get_dev_journal(struct super_block *sb,
 	unsigned long offset;
 	struct ext4_super_block *es;
 	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 
 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
 		return NULL;
 
 	/* see get_tree_bdev why this is needed and safe */
 	up_write(&sb->s_umount);
-	bdev = ext4_blkdev_get(j_dev, sb);
+	bdev_handle = ext4_blkdev_get(j_dev, sb);
 	down_write(&sb->s_umount);
-	if (bdev == NULL)
+	if (!bdev_handle)
 		return NULL;
 
+	bdev = bdev_handle->bdev;
 	blocksize = sb->s_blocksize;
 	hblock = bdev_logical_block_size(bdev);
 	if (blocksize < hblock) {
@@ -5914,14 +5914,14 @@ static journal_t *ext4_get_dev_journal(struct super_block *sb,
 			be32_to_cpu(journal->j_superblock->s_nr_users));
 		goto out_journal;
 	}
-	EXT4_SB(sb)->s_journal_bdev = bdev;
+	EXT4_SB(sb)->s_journal_bdev_handle = bdev_handle;
 	ext4_init_journal_params(sb, journal);
 	return journal;
 
 out_journal:
 	jbd2_journal_destroy(journal);
 out_bdev:
-	blkdev_put(bdev, sb);
+	bdev_release(bdev_handle);
 	return NULL;
 }
 
-- 
2.35.3

[PATCH 23/29] f2fs: Convert to bdev_open_by_dev/path()

[Jan Kara]

Convert f2fs to use bdev_open_by_dev/path() and pass the handle around.

CC: Jaegeuk Kim <jaegeuk@kernel.org>
CC: Chao Yu <chao@kernel.org>
CC: linux-f2fs-devel@lists.sourceforge.net
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/f2fs/f2fs.h  |  1 +
 fs/f2fs/super.c | 17 +++++++++--------
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index e18272ae3119..2ec6c10df636 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -1234,6 +1234,7 @@ struct f2fs_bio_info {
 #define FDEV(i)				(sbi->devs[i])
 #define RDEV(i)				(raw_super->devs[i])
 struct f2fs_dev_info {
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 	char path[MAX_PATH_LEN];
 	unsigned int total_segments;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index aa1f9a3a8037..885dcbd81859 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -1561,7 +1561,7 @@ static void destroy_device_list(struct f2fs_sb_info *sbi)
 	int i;
 
 	for (i = 0; i < sbi->s_ndevs; i++) {
-		blkdev_put(FDEV(i).bdev, sbi->sb);
+		bdev_release(FDEV(i).bdev_handle);
 #ifdef CONFIG_BLK_DEV_ZONED
 		kvfree(FDEV(i).blkz_seq);
 #endif
@@ -4196,9 +4196,9 @@ static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
 
 		if (max_devices == 1) {
 			/* Single zoned block device mount */
-			FDEV(0).bdev =
-				blkdev_get_by_dev(sbi->sb->s_bdev->bd_dev, mode,
-						  sbi->sb, NULL);
+			FDEV(0).bdev_handle = bdev_open_by_dev(
+					sbi->sb->s_bdev->bd_dev, mode, sbi->sb,
+					NULL);
 		} else {
 			/* Multi-device mount */
 			memcpy(FDEV(i).path, RDEV(i).path, MAX_PATH_LEN);
@@ -4216,12 +4216,13 @@ static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
 					(FDEV(i).total_segments <<
 					sbi->log_blocks_per_seg) - 1;
 			}
-			FDEV(i).bdev = blkdev_get_by_path(FDEV(i).path, mode,
-							  sbi->sb, NULL);
+			FDEV(i).bdev_handle = bdev_open_by_path(FDEV(i).path,
+					mode, sbi->sb, NULL);
 		}
-		if (IS_ERR(FDEV(i).bdev))
-			return PTR_ERR(FDEV(i).bdev);
+		if (IS_ERR(FDEV(i).bdev_handle))
+			return PTR_ERR(FDEV(i).bdev_handle);
 
+		FDEV(i).bdev = FDEV(i).bdev_handle->bdev;
 		/* to release errored devices */
 		sbi->s_ndevs = i + 1;
 
-- 
2.35.3

[PATCH 24/29] jfs: Convert to bdev_open_by_dev()

[Jan Kara]

Convert jfs to use bdev_open_by_dev() and pass the handle around.

CC: Dave Kleikamp <shaggy@kernel.org>
CC: jfs-discussion@lists.sourceforge.net
Acked-by: Dave Kleikamp <dave.kleikamp@oracle.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/jfs/jfs_logmgr.c | 29 +++++++++++++++--------------
 fs/jfs/jfs_logmgr.h |  2 +-
 fs/jfs/jfs_mount.c  |  3 ++-
 3 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
index e855b8fde76c..c911d838b8ec 100644
--- a/fs/jfs/jfs_logmgr.c
+++ b/fs/jfs/jfs_logmgr.c
@@ -1058,7 +1058,7 @@ void jfs_syncpt(struct jfs_log *log, int hard_sync)
 int lmLogOpen(struct super_block *sb)
 {
 	int rc;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	struct jfs_log *log;
 	struct jfs_sb_info *sbi = JFS_SBI(sb);
 
@@ -1070,7 +1070,7 @@ int lmLogOpen(struct super_block *sb)
 
 	mutex_lock(&jfs_log_mutex);
 	list_for_each_entry(log, &jfs_external_logs, journal_list) {
-		if (log->bdev->bd_dev == sbi->logdev) {
+		if (log->bdev_handle->bdev->bd_dev == sbi->logdev) {
 			if (!uuid_equal(&log->uuid, &sbi->loguuid)) {
 				jfs_warn("wrong uuid on JFS journal");
 				mutex_unlock(&jfs_log_mutex);
@@ -1100,14 +1100,14 @@ int lmLogOpen(struct super_block *sb)
 	 * file systems to log may have n-to-1 relationship;
 	 */
 
-	bdev = blkdev_get_by_dev(sbi->logdev, BLK_OPEN_READ | BLK_OPEN_WRITE,
-				 log, NULL);
-	if (IS_ERR(bdev)) {
-		rc = PTR_ERR(bdev);
+	bdev_handle = bdev_open_by_dev(sbi->logdev,
+			BLK_OPEN_READ | BLK_OPEN_WRITE, log, NULL);
+	if (IS_ERR(bdev_handle)) {
+		rc = PTR_ERR(bdev_handle);
 		goto free;
 	}
 
-	log->bdev = bdev;
+	log->bdev_handle = bdev_handle;
 	uuid_copy(&log->uuid, &sbi->loguuid);
 
 	/*
@@ -1141,7 +1141,7 @@ int lmLogOpen(struct super_block *sb)
 	lbmLogShutdown(log);
 
       close:		/* close external log device */
-	blkdev_put(bdev, log);
+	bdev_release(bdev_handle);
 
       free:		/* free log descriptor */
 	mutex_unlock(&jfs_log_mutex);
@@ -1162,7 +1162,7 @@ static int open_inline_log(struct super_block *sb)
 	init_waitqueue_head(&log->syncwait);
 
 	set_bit(log_INLINELOG, &log->flag);
-	log->bdev = sb->s_bdev;
+	log->bdev_handle = sb->s_bdev_handle;
 	log->base = addressPXD(&JFS_SBI(sb)->logpxd);
 	log->size = lengthPXD(&JFS_SBI(sb)->logpxd) >>
 	    (L2LOGPSIZE - sb->s_blocksize_bits);
@@ -1436,7 +1436,7 @@ int lmLogClose(struct super_block *sb)
 {
 	struct jfs_sb_info *sbi = JFS_SBI(sb);
 	struct jfs_log *log = sbi->log;
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	int rc = 0;
 
 	jfs_info("lmLogClose: log:0x%p", log);
@@ -1482,10 +1482,10 @@ int lmLogClose(struct super_block *sb)
 	 *	external log as separate logical volume
 	 */
 	list_del(&log->journal_list);
-	bdev = log->bdev;
+	bdev_handle = log->bdev_handle;
 	rc = lmLogShutdown(log);
 
-	blkdev_put(bdev, log);
+	bdev_release(bdev_handle);
 
 	kfree(log);
 
@@ -1972,7 +1972,7 @@ static int lbmRead(struct jfs_log * log, int pn, struct lbuf ** bpp)
 
 	bp->l_flag |= lbmREAD;
 
-	bio = bio_alloc(log->bdev, 1, REQ_OP_READ, GFP_NOFS);
+	bio = bio_alloc(log->bdev_handle->bdev, 1, REQ_OP_READ, GFP_NOFS);
 	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
 	__bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
 	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
@@ -2113,7 +2113,8 @@ static void lbmStartIO(struct lbuf * bp)
 
 	jfs_info("lbmStartIO");
 
-	bio = bio_alloc(log->bdev, 1, REQ_OP_WRITE | REQ_SYNC, GFP_NOFS);
+	bio = bio_alloc(log->bdev_handle->bdev, 1, REQ_OP_WRITE | REQ_SYNC,
+			GFP_NOFS);
 	bio->bi_iter.bi_sector = bp->l_blkno << (log->l2bsize - 9);
 	__bio_add_page(bio, bp->l_page, LOGPSIZE, bp->l_offset);
 	BUG_ON(bio->bi_iter.bi_size != LOGPSIZE);
diff --git a/fs/jfs/jfs_logmgr.h b/fs/jfs/jfs_logmgr.h
index 805877ce5020..84aa2d253907 100644
--- a/fs/jfs/jfs_logmgr.h
+++ b/fs/jfs/jfs_logmgr.h
@@ -356,7 +356,7 @@ struct jfs_log {
 				 *    before writing syncpt.
 				 */
 	struct list_head journal_list; /* Global list */
-	struct block_device *bdev; /* 4: log lv pointer */
+	struct bdev_handle *bdev_handle; /* 4: log lv pointer */
 	int serial;		/* 4: log mount serial number */
 
 	s64 base;		/* @8: log extent address (inline log ) */
diff --git a/fs/jfs/jfs_mount.c b/fs/jfs/jfs_mount.c
index b83aae56a1f2..415eb65a36ff 100644
--- a/fs/jfs/jfs_mount.c
+++ b/fs/jfs/jfs_mount.c
@@ -430,7 +430,8 @@ int updateSuper(struct super_block *sb, uint state)
 
 	if (state == FM_MOUNT) {
 		/* record log's dev_t and mount serial number */
-		j_sb->s_logdev = cpu_to_le32(new_encode_dev(sbi->log->bdev->bd_dev));
+		j_sb->s_logdev = cpu_to_le32(
+			new_encode_dev(sbi->log->bdev_handle->bdev->bd_dev));
 		j_sb->s_logserial = cpu_to_le32(sbi->log->serial);
 	} else if (state == FM_CLEAN) {
 		/*
-- 
2.35.3

[PATCH 25/29] nfs/blocklayout: Convert to use bdev_open_by_dev/path()

[Jan Kara]

Convert block device handling to use bdev_open_by_dev/path() and pass
the handle around.

CC: linux-nfs@vger.kernel.org
CC: Trond Myklebust <trond.myklebust@hammerspace.com>
CC: Anna Schumaker <anna@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/nfs/blocklayout/blocklayout.h |  2 +-
 fs/nfs/blocklayout/dev.c         | 76 ++++++++++++++++----------------
 2 files changed, 38 insertions(+), 40 deletions(-)

diff --git a/fs/nfs/blocklayout/blocklayout.h b/fs/nfs/blocklayout/blocklayout.h
index 716bc75e9ed2..b4294a8aa2d4 100644
--- a/fs/nfs/blocklayout/blocklayout.h
+++ b/fs/nfs/blocklayout/blocklayout.h
@@ -108,7 +108,7 @@ struct pnfs_block_dev {
 	struct pnfs_block_dev		*children;
 	u64				chunk_size;
 
-	struct block_device		*bdev;
+	struct bdev_handle		*bdev_handle;
 	u64				disk_offset;
 
 	u64				pr_key;
diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c
index 70f5563a8e81..0b57b8a4b7e2 100644
--- a/fs/nfs/blocklayout/dev.c
+++ b/fs/nfs/blocklayout/dev.c
@@ -25,17 +25,17 @@ bl_free_device(struct pnfs_block_dev *dev)
 	} else {
 		if (dev->pr_registered) {
 			const struct pr_ops *ops =
-				dev->bdev->bd_disk->fops->pr_ops;
+				dev->bdev_handle->bdev->bd_disk->fops->pr_ops;
 			int error;
 
-			error = ops->pr_register(dev->bdev, dev->pr_key, 0,
-				false);
+			error = ops->pr_register(dev->bdev_handle->bdev,
+				dev->pr_key, 0, false);
 			if (error)
 				pr_err("failed to unregister PR key.\n");
 		}
 
-		if (dev->bdev)
-			blkdev_put(dev->bdev, NULL);
+		if (dev->bdev_handle)
+			bdev_release(dev->bdev_handle);
 	}
 }
 
@@ -169,7 +169,7 @@ static bool bl_map_simple(struct pnfs_block_dev *dev, u64 offset,
 	map->start = dev->start;
 	map->len = dev->len;
 	map->disk_offset = dev->disk_offset;
-	map->bdev = dev->bdev;
+	map->bdev = dev->bdev_handle->bdev;
 	return true;
 }
 
@@ -236,28 +236,26 @@ bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 {
 	struct pnfs_block_volume *v = &volumes[idx];
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	dev_t dev;
 
 	dev = bl_resolve_deviceid(server, v, gfp_mask);
 	if (!dev)
 		return -EIO;
 
-	bdev = blkdev_get_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE, NULL,
-				 NULL);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
+				       NULL, NULL);
+	if (IS_ERR(bdev_handle)) {
 		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
-			MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
-		return PTR_ERR(bdev);
+			MAJOR(dev), MINOR(dev), PTR_ERR(bdev_handle));
+		return PTR_ERR(bdev_handle);
 	}
-	d->bdev = bdev;
-
-
-	d->len = bdev_nr_bytes(d->bdev);
+	d->bdev_handle = bdev_handle;
+	d->len = bdev_nr_bytes(bdev_handle->bdev);
 	d->map = bl_map_simple;
 
 	printk(KERN_INFO "pNFS: using block device %s\n",
-		d->bdev->bd_disk->disk_name);
+		bdev_handle->bdev->bd_disk->disk_name);
 	return 0;
 }
 
@@ -302,10 +300,10 @@ bl_validate_designator(struct pnfs_block_volume *v)
 	}
 }
 
-static struct block_device *
+static struct bdev_handle *
 bl_open_path(struct pnfs_block_volume *v, const char *prefix)
 {
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	const char *devname;
 
 	devname = kasprintf(GFP_KERNEL, "/dev/disk/by-id/%s%*phN",
@@ -313,15 +311,15 @@ bl_open_path(struct pnfs_block_volume *v, const char *prefix)
 	if (!devname)
 		return ERR_PTR(-ENOMEM);
 
-	bdev = blkdev_get_by_path(devname, BLK_OPEN_READ | BLK_OPEN_WRITE, NULL,
-				  NULL);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_path(devname, BLK_OPEN_READ | BLK_OPEN_WRITE,
+					NULL, NULL);
+	if (IS_ERR(bdev_handle)) {
 		pr_warn("pNFS: failed to open device %s (%ld)\n",
-			devname, PTR_ERR(bdev));
+			devname, PTR_ERR(bdev_handle));
 	}
 
 	kfree(devname);
-	return bdev;
+	return bdev_handle;
 }
 
 static int
@@ -329,7 +327,7 @@ bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
 		struct pnfs_block_volume *volumes, int idx, gfp_t gfp_mask)
 {
 	struct pnfs_block_volume *v = &volumes[idx];
-	struct block_device *bdev;
+	struct bdev_handle *bdev_handle;
 	const struct pr_ops *ops;
 	int error;
 
@@ -342,32 +340,32 @@ bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
 	 * On other distributions like Debian, the default SCSI by-id path will
 	 * point to the dm-multipath device if one exists.
 	 */
-	bdev = bl_open_path(v, "dm-uuid-mpath-0x");
-	if (IS_ERR(bdev))
-		bdev = bl_open_path(v, "wwn-0x");
-	if (IS_ERR(bdev))
-		return PTR_ERR(bdev);
-	d->bdev = bdev;
-
-	d->len = bdev_nr_bytes(d->bdev);
+	bdev_handle = bl_open_path(v, "dm-uuid-mpath-0x");
+	if (IS_ERR(bdev_handle))
+		bdev_handle = bl_open_path(v, "wwn-0x");
+	if (IS_ERR(bdev_handle))
+		return PTR_ERR(bdev_handle);
+	d->bdev_handle = bdev_handle;
+
+	d->len = bdev_nr_bytes(d->bdev_handle->bdev);
 	d->map = bl_map_simple;
 	d->pr_key = v->scsi.pr_key;
 
 	pr_info("pNFS: using block device %s (reservation key 0x%llx)\n",
-		d->bdev->bd_disk->disk_name, d->pr_key);
+		d->bdev_handle->bdev->bd_disk->disk_name, d->pr_key);
 
-	ops = d->bdev->bd_disk->fops->pr_ops;
+	ops = d->bdev_handle->bdev->bd_disk->fops->pr_ops;
 	if (!ops) {
 		pr_err("pNFS: block device %s does not support reservations.",
-				d->bdev->bd_disk->disk_name);
+				d->bdev_handle->bdev->bd_disk->disk_name);
 		error = -EINVAL;
 		goto out_blkdev_put;
 	}
 
-	error = ops->pr_register(d->bdev, 0, d->pr_key, true);
+	error = ops->pr_register(d->bdev_handle->bdev, 0, d->pr_key, true);
 	if (error) {
 		pr_err("pNFS: failed to register key for block device %s.",
-				d->bdev->bd_disk->disk_name);
+				d->bdev_handle->bdev->bd_disk->disk_name);
 		goto out_blkdev_put;
 	}
 
@@ -375,7 +373,7 @@ bl_parse_scsi(struct nfs_server *server, struct pnfs_block_dev *d,
 	return 0;
 
 out_blkdev_put:
-	blkdev_put(d->bdev, NULL);
+	bdev_release(d->bdev_handle);
 	return error;
 }
 
-- 
2.35.3

[PATCH 26/29] ocfs2: Convert to use bdev_open_by_dev()

[Jan Kara]

Convert ocfs2 heartbeat code to use bdev_open_by_dev() and pass the
handle around.

CC: Joseph Qi <joseph.qi@linux.alibaba.com>
CC: ocfs2-devel@oss.oracle.com
Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/ocfs2/cluster/heartbeat.c | 81 ++++++++++++++++++++----------------
 1 file changed, 45 insertions(+), 36 deletions(-)

diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 21472e3ed182..4d7efefa98c5 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -213,7 +213,7 @@ struct o2hb_region {
 	unsigned int		hr_num_pages;
 
 	struct page             **hr_slot_data;
-	struct block_device	*hr_bdev;
+	struct bdev_handle	*hr_bdev_handle;
 	struct o2hb_disk_slot	*hr_slots;
 
 	/* live node map of this region */
@@ -261,6 +261,11 @@ struct o2hb_region {
 	int			hr_last_hb_status;
 };
 
+static inline struct block_device *reg_bdev(struct o2hb_region *reg)
+{
+	return reg->hr_bdev_handle ? reg->hr_bdev_handle->bdev : NULL;
+}
+
 struct o2hb_bio_wait_ctxt {
 	atomic_t          wc_num_reqs;
 	struct completion wc_io_complete;
@@ -286,7 +291,7 @@ static void o2hb_write_timeout(struct work_struct *work)
 			     hr_write_timeout_work.work);
 
 	mlog(ML_ERROR, "Heartbeat write timeout to device %pg after %u "
-	     "milliseconds\n", reg->hr_bdev,
+	     "milliseconds\n", reg_bdev(reg),
 	     jiffies_to_msecs(jiffies - reg->hr_last_timeout_start));
 
 	if (o2hb_global_heartbeat_active()) {
@@ -383,7 +388,7 @@ static void o2hb_nego_timeout(struct work_struct *work)
 		if (!test_bit(master_node, reg->hr_nego_node_bitmap)) {
 			printk(KERN_NOTICE "o2hb: node %d hb write hung for %ds on region %s (%pg).\n",
 				o2nm_this_node(), O2HB_NEGO_TIMEOUT_MS/1000,
-				config_item_name(&reg->hr_item), reg->hr_bdev);
+				config_item_name(&reg->hr_item), reg_bdev(reg));
 			set_bit(master_node, reg->hr_nego_node_bitmap);
 		}
 		if (!bitmap_equal(reg->hr_nego_node_bitmap, live_node_bitmap,
@@ -398,7 +403,8 @@ static void o2hb_nego_timeout(struct work_struct *work)
 		}
 
 		printk(KERN_NOTICE "o2hb: all nodes hb write hung, maybe region %s (%pg) is down.\n",
-			config_item_name(&reg->hr_item), reg->hr_bdev);
+			config_item_name(&reg->hr_item),
+			reg_bdev(reg));
 		/* approve negotiate timeout request. */
 		o2hb_arm_timeout(reg);
 
@@ -419,7 +425,7 @@ static void o2hb_nego_timeout(struct work_struct *work)
 		/* negotiate timeout with master node. */
 		printk(KERN_NOTICE "o2hb: node %d hb write hung for %ds on region %s (%pg), negotiate timeout with node %d.\n",
 			o2nm_this_node(), O2HB_NEGO_TIMEOUT_MS/1000, config_item_name(&reg->hr_item),
-			reg->hr_bdev, master_node);
+			reg_bdev(reg), master_node);
 		ret = o2hb_send_nego_msg(reg->hr_key, O2HB_NEGO_TIMEOUT_MSG,
 				master_node);
 		if (ret)
@@ -436,7 +442,8 @@ static int o2hb_nego_timeout_handler(struct o2net_msg *msg, u32 len, void *data,
 
 	nego_msg = (struct o2hb_nego_msg *)msg->buf;
 	printk(KERN_NOTICE "o2hb: receive negotiate timeout message from node %d on region %s (%pg).\n",
-		nego_msg->node_num, config_item_name(&reg->hr_item), reg->hr_bdev);
+		nego_msg->node_num, config_item_name(&reg->hr_item),
+		reg_bdev(reg));
 	if (nego_msg->node_num < O2NM_MAX_NODES)
 		set_bit(nego_msg->node_num, reg->hr_nego_node_bitmap);
 	else
@@ -451,7 +458,7 @@ static int o2hb_nego_approve_handler(struct o2net_msg *msg, u32 len, void *data,
 	struct o2hb_region *reg = data;
 
 	printk(KERN_NOTICE "o2hb: negotiate timeout approved by master node on region %s (%pg).\n",
-		config_item_name(&reg->hr_item), reg->hr_bdev);
+		config_item_name(&reg->hr_item), reg_bdev(reg));
 	o2hb_arm_timeout(reg);
 	return 0;
 }
@@ -515,7 +522,7 @@ static struct bio *o2hb_setup_one_bio(struct o2hb_region *reg,
 	 * GFP_KERNEL that the local node can get fenced. It would be
 	 * nicest if we could pre-allocate these bios and avoid this
 	 * all together. */
-	bio = bio_alloc(reg->hr_bdev, 16, opf, GFP_ATOMIC);
+	bio = bio_alloc(reg_bdev(reg), 16, opf, GFP_ATOMIC);
 	if (!bio) {
 		mlog(ML_ERROR, "Could not alloc slots BIO!\n");
 		bio = ERR_PTR(-ENOMEM);
@@ -687,7 +694,7 @@ static int o2hb_check_own_slot(struct o2hb_region *reg)
 		errstr = ERRSTR3;
 
 	mlog(ML_ERROR, "%s (%pg): expected(%u:0x%llx, 0x%llx), "
-	     "ondisk(%u:0x%llx, 0x%llx)\n", errstr, reg->hr_bdev,
+	     "ondisk(%u:0x%llx, 0x%llx)\n", errstr, reg_bdev(reg),
 	     slot->ds_node_num, (unsigned long long)slot->ds_last_generation,
 	     (unsigned long long)slot->ds_last_time, hb_block->hb_node,
 	     (unsigned long long)le64_to_cpu(hb_block->hb_generation),
@@ -861,7 +868,7 @@ static void o2hb_set_quorum_device(struct o2hb_region *reg)
 		goto unlock;
 
 	printk(KERN_NOTICE "o2hb: Region %s (%pg) is now a quorum device\n",
-	       config_item_name(&reg->hr_item), reg->hr_bdev);
+	       config_item_name(&reg->hr_item), reg_bdev(reg));
 
 	set_bit(reg->hr_region_num, o2hb_quorum_region_bitmap);
 
@@ -920,7 +927,7 @@ static int o2hb_check_slot(struct o2hb_region *reg,
 		 * consider it a transient miss but don't populate any
 		 * other values as they may be junk. */
 		mlog(ML_ERROR, "Node %d has written a bad crc to %pg\n",
-		     slot->ds_node_num, reg->hr_bdev);
+		     slot->ds_node_num, reg_bdev(reg));
 		o2hb_dump_slot(hb_block);
 
 		slot->ds_equal_samples++;
@@ -1003,8 +1010,8 @@ static int o2hb_check_slot(struct o2hb_region *reg,
 			     "of %u ms, but our count is %u ms.\n"
 			     "Please double check your configuration values "
 			     "for 'O2CB_HEARTBEAT_THRESHOLD'\n",
-			     slot->ds_node_num, reg->hr_bdev, slot_dead_ms,
-			     dead_ms);
+			     slot->ds_node_num, reg_bdev(reg),
+			     slot_dead_ms, dead_ms);
 		}
 		goto out;
 	}
@@ -1143,7 +1150,7 @@ static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
 		 * can't be sure that the new block ever made it to
 		 * disk */
 		mlog(ML_ERROR, "Write error %d on device \"%pg\"\n",
-		     write_wc.wc_error, reg->hr_bdev);
+		     write_wc.wc_error, reg_bdev(reg));
 		ret = write_wc.wc_error;
 		goto bail;
 	}
@@ -1169,7 +1176,7 @@ static int o2hb_do_disk_heartbeat(struct o2hb_region *reg)
 			printk(KERN_NOTICE "o2hb: Unable to stabilize "
 			       "heartbeat on region %s (%pg)\n",
 			       config_item_name(&reg->hr_item),
-			       reg->hr_bdev);
+			       reg_bdev(reg));
 			atomic_set(&reg->hr_steady_iterations, 0);
 			reg->hr_aborted_start = 1;
 			wake_up(&o2hb_steady_queue);
@@ -1489,7 +1496,7 @@ static void o2hb_region_release(struct config_item *item)
 	struct page *page;
 	struct o2hb_region *reg = to_o2hb_region(item);
 
-	mlog(ML_HEARTBEAT, "hb region release (%pg)\n", reg->hr_bdev);
+	mlog(ML_HEARTBEAT, "hb region release (%pg)\n", reg_bdev(reg));
 
 	kfree(reg->hr_tmp_block);
 
@@ -1502,8 +1509,8 @@ static void o2hb_region_release(struct config_item *item)
 		kfree(reg->hr_slot_data);
 	}
 
-	if (reg->hr_bdev)
-		blkdev_put(reg->hr_bdev, NULL);
+	if (reg->hr_bdev_handle)
+		bdev_release(reg->hr_bdev_handle);
 
 	kfree(reg->hr_slots);
 
@@ -1562,7 +1569,7 @@ static ssize_t o2hb_region_block_bytes_store(struct config_item *item,
 	unsigned long block_bytes;
 	unsigned int block_bits;
 
-	if (reg->hr_bdev)
+	if (reg->hr_bdev_handle)
 		return -EINVAL;
 
 	status = o2hb_read_block_input(reg, page, &block_bytes,
@@ -1591,7 +1598,7 @@ static ssize_t o2hb_region_start_block_store(struct config_item *item,
 	char *p = (char *)page;
 	ssize_t ret;
 
-	if (reg->hr_bdev)
+	if (reg->hr_bdev_handle)
 		return -EINVAL;
 
 	ret = kstrtoull(p, 0, &tmp);
@@ -1616,7 +1623,7 @@ static ssize_t o2hb_region_blocks_store(struct config_item *item,
 	unsigned long tmp;
 	char *p = (char *)page;
 
-	if (reg->hr_bdev)
+	if (reg->hr_bdev_handle)
 		return -EINVAL;
 
 	tmp = simple_strtoul(p, &p, 0);
@@ -1635,8 +1642,8 @@ static ssize_t o2hb_region_dev_show(struct config_item *item, char *page)
 {
 	unsigned int ret = 0;
 
-	if (to_o2hb_region(item)->hr_bdev)
-		ret = sprintf(page, "%pg\n", to_o2hb_region(item)->hr_bdev);
+	if (to_o2hb_region(item)->hr_bdev_handle)
+		ret = sprintf(page, "%pg\n", reg_bdev(to_o2hb_region(item)));
 
 	return ret;
 }
@@ -1745,7 +1752,10 @@ static int o2hb_populate_slot_data(struct o2hb_region *reg)
 	return ret;
 }
 
-/* this is acting as commit; we set up all of hr_bdev and hr_task or nothing */
+/*
+ * this is acting as commit; we set up all of hr_bdev_handle and hr_task or
+ * nothing
+ */
 static ssize_t o2hb_region_dev_store(struct config_item *item,
 				     const char *page,
 				     size_t count)
@@ -1759,7 +1769,7 @@ static ssize_t o2hb_region_dev_store(struct config_item *item,
 	ssize_t ret = -EINVAL;
 	int live_threshold;
 
-	if (reg->hr_bdev)
+	if (reg->hr_bdev_handle)
 		goto out;
 
 	/* We can't heartbeat without having had our node number
@@ -1785,16 +1795,15 @@ static ssize_t o2hb_region_dev_store(struct config_item *item,
 	if (!S_ISBLK(f.file->f_mapping->host->i_mode))
 		goto out2;
 
-	reg->hr_bdev = blkdev_get_by_dev(f.file->f_mapping->host->i_rdev,
-					 BLK_OPEN_WRITE | BLK_OPEN_READ, NULL,
-					 NULL);
-	if (IS_ERR(reg->hr_bdev)) {
-		ret = PTR_ERR(reg->hr_bdev);
-		reg->hr_bdev = NULL;
+	reg->hr_bdev_handle = bdev_open_by_dev(f.file->f_mapping->host->i_rdev,
+			BLK_OPEN_WRITE | BLK_OPEN_READ, NULL, NULL);
+	if (IS_ERR(reg->hr_bdev_handle)) {
+		ret = PTR_ERR(reg->hr_bdev_handle);
+		reg->hr_bdev_handle = NULL;
 		goto out2;
 	}
 
-	sectsize = bdev_logical_block_size(reg->hr_bdev);
+	sectsize = bdev_logical_block_size(reg_bdev(reg));
 	if (sectsize != reg->hr_block_bytes) {
 		mlog(ML_ERROR,
 		     "blocksize %u incorrect for device, expected %d",
@@ -1890,12 +1899,12 @@ static ssize_t o2hb_region_dev_store(struct config_item *item,
 
 	if (hb_task && o2hb_global_heartbeat_active())
 		printk(KERN_NOTICE "o2hb: Heartbeat started on region %s (%pg)\n",
-		       config_item_name(&reg->hr_item), reg->hr_bdev);
+		       config_item_name(&reg->hr_item), reg_bdev(reg));
 
 out3:
 	if (ret < 0) {
-		blkdev_put(reg->hr_bdev, NULL);
-		reg->hr_bdev = NULL;
+		bdev_release(reg->hr_bdev_handle);
+		reg->hr_bdev_handle = NULL;
 	}
 out2:
 	fdput(f);
@@ -2085,7 +2094,7 @@ static void o2hb_heartbeat_group_drop_item(struct config_group *group,
 		printk(KERN_NOTICE "o2hb: Heartbeat %s on region %s (%pg)\n",
 		       ((atomic_read(&reg->hr_steady_iterations) == 0) ?
 			"stopped" : "start aborted"), config_item_name(item),
-		       reg->hr_bdev);
+		       reg_bdev(reg));
 	}
 
 	/*
-- 
2.35.3

[PATCH 27/29] reiserfs: Convert to bdev_open_by_dev/path()

[Jan Kara]

Convert reiserfs to use bdev_open_by_dev/path() and pass the handle
around.

CC: reiserfs-devel@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/reiserfs/journal.c  | 56 +++++++++++++++++++-----------------------
 fs/reiserfs/procfs.c   |  2 +-
 fs/reiserfs/reiserfs.h | 11 ++++++---
 3 files changed, 33 insertions(+), 36 deletions(-)

diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index 015bfe4e4524..171c912af50f 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -90,8 +90,7 @@ static int flush_commit_list(struct super_block *s,
 static int can_dirty(struct reiserfs_journal_cnode *cn);
 static int journal_join(struct reiserfs_transaction_handle *th,
 			struct super_block *sb);
-static void release_journal_dev(struct super_block *super,
-			       struct reiserfs_journal *journal);
+static void release_journal_dev(struct reiserfs_journal *journal);
 static void dirty_one_transaction(struct super_block *s,
 				 struct reiserfs_journal_list *jl);
 static void flush_async_commits(struct work_struct *work);
@@ -1893,7 +1892,7 @@ static void free_journal_ram(struct super_block *sb)
 	 * j_header_bh is on the journal dev, make sure
 	 * not to release the journal dev until we brelse j_header_bh
 	 */
-	release_journal_dev(sb, journal);
+	release_journal_dev(journal);
 	vfree(journal);
 }
 
@@ -2387,7 +2386,7 @@ static int journal_read(struct super_block *sb)
 
 	cur_dblock = SB_ONDISK_JOURNAL_1st_BLOCK(sb);
 	reiserfs_info(sb, "checking transaction log (%pg)\n",
-		      journal->j_dev_bd);
+		      journal->j_bdev_handle->bdev);
 	start = ktime_get_seconds();
 
 	/*
@@ -2448,7 +2447,7 @@ static int journal_read(struct super_block *sb)
 		 * device and journal device to be the same
 		 */
 		d_bh =
-		    reiserfs_breada(journal->j_dev_bd, cur_dblock,
+		    reiserfs_breada(journal->j_bdev_handle->bdev, cur_dblock,
 				    sb->s_blocksize,
 				    SB_ONDISK_JOURNAL_1st_BLOCK(sb) +
 				    SB_ONDISK_JOURNAL_SIZE(sb));
@@ -2587,17 +2586,11 @@ static void journal_list_init(struct super_block *sb)
 	SB_JOURNAL(sb)->j_current_jl = alloc_journal_list(sb);
 }
 
-static void release_journal_dev(struct super_block *super,
-			       struct reiserfs_journal *journal)
+static void release_journal_dev(struct reiserfs_journal *journal)
 {
-	if (journal->j_dev_bd != NULL) {
-		void *holder = NULL;
-
-		if (journal->j_dev_bd->bd_dev != super->s_dev)
-			holder = journal;
-
-		blkdev_put(journal->j_dev_bd, holder);
-		journal->j_dev_bd = NULL;
+	if (journal->j_bdev_handle) {
+		bdev_release(journal->j_bdev_handle);
+		journal->j_bdev_handle = NULL;
 	}
 }
 
@@ -2612,7 +2605,7 @@ static int journal_init_dev(struct super_block *super,
 
 	result = 0;
 
-	journal->j_dev_bd = NULL;
+	journal->j_bdev_handle = NULL;
 	jdev = SB_ONDISK_JOURNAL_DEVICE(super) ?
 	    new_decode_dev(SB_ONDISK_JOURNAL_DEVICE(super)) : super->s_dev;
 
@@ -2623,36 +2616,37 @@ static int journal_init_dev(struct super_block *super,
 	if ((!jdev_name || !jdev_name[0])) {
 		if (jdev == super->s_dev)
 			holder = NULL;
-		journal->j_dev_bd = blkdev_get_by_dev(jdev, blkdev_mode, holder,
-						      NULL);
-		if (IS_ERR(journal->j_dev_bd)) {
-			result = PTR_ERR(journal->j_dev_bd);
-			journal->j_dev_bd = NULL;
+		journal->j_bdev_handle = bdev_open_by_dev(jdev, blkdev_mode,
+							  holder, NULL);
+		if (IS_ERR(journal->j_bdev_handle)) {
+			result = PTR_ERR(journal->j_bdev_handle);
+			journal->j_bdev_handle = NULL;
 			reiserfs_warning(super, "sh-458",
 					 "cannot init journal device unknown-block(%u,%u): %i",
 					 MAJOR(jdev), MINOR(jdev), result);
 			return result;
 		} else if (jdev != super->s_dev)
-			set_blocksize(journal->j_dev_bd, super->s_blocksize);
+			set_blocksize(journal->j_bdev_handle->bdev,
+				      super->s_blocksize);
 
 		return 0;
 	}
 
-	journal->j_dev_bd = blkdev_get_by_path(jdev_name, blkdev_mode, holder,
-					       NULL);
-	if (IS_ERR(journal->j_dev_bd)) {
-		result = PTR_ERR(journal->j_dev_bd);
-		journal->j_dev_bd = NULL;
+	journal->j_bdev_handle = bdev_open_by_path(jdev_name, blkdev_mode,
+						   holder, NULL);
+	if (IS_ERR(journal->j_bdev_handle)) {
+		result = PTR_ERR(journal->j_bdev_handle);
+		journal->j_bdev_handle = NULL;
 		reiserfs_warning(super, "sh-457",
 				 "journal_init_dev: Cannot open '%s': %i",
 				 jdev_name, result);
 		return result;
 	}
 
-	set_blocksize(journal->j_dev_bd, super->s_blocksize);
+	set_blocksize(journal->j_bdev_handle->bdev, super->s_blocksize);
 	reiserfs_info(super,
 		      "journal_init_dev: journal device: %pg\n",
-		      journal->j_dev_bd);
+		      journal->j_bdev_handle->bdev);
 	return 0;
 }
 
@@ -2810,7 +2804,7 @@ int journal_init(struct super_block *sb, const char *j_dev_name,
 				 "journal header magic %x (device %pg) does "
 				 "not match to magic found in super block %x",
 				 jh->jh_journal.jp_journal_magic,
-				 journal->j_dev_bd,
+				 journal->j_bdev_handle->bdev,
 				 sb_jp_journal_magic(rs));
 		brelse(bhjh);
 		goto free_and_return;
@@ -2834,7 +2828,7 @@ int journal_init(struct super_block *sb, const char *j_dev_name,
 	reiserfs_info(sb, "journal params: device %pg, size %u, "
 		      "journal first block %u, max trans len %u, max batch %u, "
 		      "max commit age %u, max trans age %u\n",
-		      journal->j_dev_bd,
+		      journal->j_bdev_handle->bdev,
 		      SB_ONDISK_JOURNAL_SIZE(sb),
 		      SB_ONDISK_JOURNAL_1st_BLOCK(sb),
 		      journal->j_trans_max,
diff --git a/fs/reiserfs/procfs.c b/fs/reiserfs/procfs.c
index 3dba8acf4e83..83cb9402e0f9 100644
--- a/fs/reiserfs/procfs.c
+++ b/fs/reiserfs/procfs.c
@@ -354,7 +354,7 @@ static int show_journal(struct seq_file *m, void *unused)
 		   "prepare: \t%12lu\n"
 		   "prepare_retry: \t%12lu\n",
 		   DJP(jp_journal_1st_block),
-		   SB_JOURNAL(sb)->j_dev_bd,
+		   SB_JOURNAL(sb)->j_bdev_handle->bdev,
 		   DJP(jp_journal_dev),
 		   DJP(jp_journal_size),
 		   DJP(jp_journal_trans_max),
diff --git a/fs/reiserfs/reiserfs.h b/fs/reiserfs/reiserfs.h
index 55e85256aae8..8e426392b5c2 100644
--- a/fs/reiserfs/reiserfs.h
+++ b/fs/reiserfs/reiserfs.h
@@ -299,7 +299,7 @@ struct reiserfs_journal {
 	/* oldest journal block.  start here for traverse */
 	struct reiserfs_journal_cnode *j_first;
 
-	struct block_device *j_dev_bd;
+	struct bdev_handle *j_bdev_handle;
 
 	/* first block on s_dev of reserved area journal */
 	int j_1st_reserved_block;
@@ -2809,9 +2809,12 @@ struct reiserfs_journal_header {
 #define journal_hash(t,sb,block) ((t)[_jhashfn((sb),(block)) & JBH_HASH_MASK])
 
 /* We need these to make journal.c code more readable */
-#define journal_find_get_block(s, block) __find_get_block(SB_JOURNAL(s)->j_dev_bd, block, s->s_blocksize)
-#define journal_getblk(s, block) __getblk(SB_JOURNAL(s)->j_dev_bd, block, s->s_blocksize)
-#define journal_bread(s, block) __bread(SB_JOURNAL(s)->j_dev_bd, block, s->s_blocksize)
+#define journal_find_get_block(s, block) __find_get_block(\
+		SB_JOURNAL(s)->j_bdev_handle->bdev, block, s->s_blocksize)
+#define journal_getblk(s, block) __getblk(SB_JOURNAL(s)->j_bdev_handle->bdev,\
+		block, s->s_blocksize)
+#define journal_bread(s, block) __bread(SB_JOURNAL(s)->j_bdev_handle->bdev,\
+		block, s->s_blocksize)
 
 enum reiserfs_bh_state_bits {
 	BH_JDirty = BH_PrivateStart,	/* buffer is in current transaction */
-- 
2.35.3

[PATCH 28/29] xfs: Convert to bdev_open_by_path()

[Jan Kara]

Convert xfs to use bdev_open_by_path() and pass the handle around.

CC: "Darrick J. Wong" <djwong@kernel.org>
CC: linux-xfs@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/xfs/xfs_buf.c   | 11 +++++-----
 fs/xfs/xfs_buf.h   |  3 ++-
 fs/xfs/xfs_super.c | 54 +++++++++++++++++++++++++---------------------
 3 files changed, 37 insertions(+), 31 deletions(-)

diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
index 15d1e5a7c2d3..461a5fb6155b 100644
--- a/fs/xfs/xfs_buf.c
+++ b/fs/xfs/xfs_buf.c
@@ -1989,7 +1989,7 @@ xfs_setsize_buftarg_early(
 struct xfs_buftarg *
 xfs_alloc_buftarg(
 	struct xfs_mount	*mp,
-	struct block_device	*bdev)
+	struct bdev_handle	*bdev_handle)
 {
 	xfs_buftarg_t		*btp;
 	const struct dax_holder_operations *ops = NULL;
@@ -2000,9 +2000,10 @@ xfs_alloc_buftarg(
 	btp = kmem_zalloc(sizeof(*btp), KM_NOFS);
 
 	btp->bt_mount = mp;
-	btp->bt_dev =  bdev->bd_dev;
-	btp->bt_bdev = bdev;
-	btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off,
+	btp->bt_bdev_handle = bdev_handle;
+	btp->bt_dev =  bdev_handle->bdev->bd_dev;
+	btp->bt_bdev = bdev_handle->bdev;
+	btp->bt_daxdev = fs_dax_get_by_bdev(btp->bt_bdev, &btp->bt_dax_part_off,
 					    mp, ops);
 
 	/*
@@ -2012,7 +2013,7 @@ xfs_alloc_buftarg(
 	ratelimit_state_init(&btp->bt_ioerror_rl, 30 * HZ,
 			     DEFAULT_RATELIMIT_BURST);
 
-	if (xfs_setsize_buftarg_early(btp, bdev))
+	if (xfs_setsize_buftarg_early(btp, btp->bt_bdev))
 		goto error_free;
 
 	if (list_lru_init(&btp->bt_lru))
diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
index 549c60942208..f6418c1312f5 100644
--- a/fs/xfs/xfs_buf.h
+++ b/fs/xfs/xfs_buf.h
@@ -92,6 +92,7 @@ typedef unsigned int xfs_buf_flags_t;
  */
 typedef struct xfs_buftarg {
 	dev_t			bt_dev;
+	struct bdev_handle	*bt_bdev_handle;
 	struct block_device	*bt_bdev;
 	struct dax_device	*bt_daxdev;
 	u64			bt_dax_part_off;
@@ -351,7 +352,7 @@ xfs_buf_update_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
  *	Handling of buftargs.
  */
 struct xfs_buftarg *xfs_alloc_buftarg(struct xfs_mount *mp,
-		struct block_device *bdev);
+		struct bdev_handle *bdev_handle);
 extern void xfs_free_buftarg(struct xfs_buftarg *);
 extern void xfs_buftarg_wait(struct xfs_buftarg *);
 extern void xfs_buftarg_drain(struct xfs_buftarg *);
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 5340f2dc28bd..6189f726b309 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -381,14 +381,15 @@ STATIC int
 xfs_blkdev_get(
 	xfs_mount_t		*mp,
 	const char		*name,
-	struct block_device	**bdevp)
+	struct bdev_handle	**handlep)
 {
 	int			error = 0;
 
-	*bdevp = blkdev_get_by_path(name, BLK_OPEN_READ | BLK_OPEN_WRITE,
-				    mp->m_super, &fs_holder_ops);
-	if (IS_ERR(*bdevp)) {
-		error = PTR_ERR(*bdevp);
+	*handlep = bdev_open_by_path(name, BLK_OPEN_READ | BLK_OPEN_WRITE,
+				     mp->m_super, &fs_holder_ops);
+	if (IS_ERR(*handlep)) {
+		error = PTR_ERR(*handlep);
+		*handlep = NULL;
 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
 	}
 
@@ -397,11 +398,10 @@ xfs_blkdev_get(
 
 STATIC void
 xfs_blkdev_put(
-	struct xfs_mount	*mp,
-	struct block_device	*bdev)
+	struct bdev_handle	*handle)
 {
-	if (bdev)
-		blkdev_put(bdev, mp->m_super);
+	if (handle)
+		bdev_release(handle);
 }
 
 STATIC void
@@ -409,16 +409,18 @@ xfs_close_devices(
 	struct xfs_mount	*mp)
 {
 	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
-		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
+		struct bdev_handle *logdev_handle =
+			mp->m_logdev_targp->bt_bdev_handle;
 
 		xfs_free_buftarg(mp->m_logdev_targp);
-		xfs_blkdev_put(mp, logdev);
+		xfs_blkdev_put(logdev_handle);
 	}
 	if (mp->m_rtdev_targp) {
-		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
+		struct bdev_handle *rtdev_handle =
+			mp->m_rtdev_targp->bt_bdev_handle;
 
 		xfs_free_buftarg(mp->m_rtdev_targp);
-		xfs_blkdev_put(mp, rtdev);
+		xfs_blkdev_put(rtdev_handle);
 	}
 	xfs_free_buftarg(mp->m_ddev_targp);
 }
@@ -439,7 +441,7 @@ xfs_open_devices(
 {
 	struct super_block	*sb = mp->m_super;
 	struct block_device	*ddev = sb->s_bdev;
-	struct block_device	*logdev = NULL, *rtdev = NULL;
+	struct bdev_handle	*logdev_handle = NULL, *rtdev_handle = NULL;
 	int			error;
 
 	/*
@@ -452,17 +454,19 @@ xfs_open_devices(
 	 * Open real time and log devices - order is important.
 	 */
 	if (mp->m_logname) {
-		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
+		error = xfs_blkdev_get(mp, mp->m_logname, &logdev_handle);
 		if (error)
 			goto out_relock;
 	}
 
 	if (mp->m_rtname) {
-		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
+		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev_handle);
 		if (error)
 			goto out_close_logdev;
 
-		if (rtdev == ddev || rtdev == logdev) {
+		if (rtdev_handle->bdev == ddev ||
+		    (logdev_handle &&
+		     rtdev_handle->bdev == logdev_handle->bdev)) {
 			xfs_warn(mp,
 	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
 			error = -EINVAL;
@@ -474,18 +478,18 @@ xfs_open_devices(
 	 * Setup xfs_mount buffer target pointers
 	 */
 	error = -ENOMEM;
-	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev);
+	mp->m_ddev_targp = xfs_alloc_buftarg(mp, sb->s_bdev_handle);
 	if (!mp->m_ddev_targp)
 		goto out_close_rtdev;
 
-	if (rtdev) {
-		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev);
+	if (rtdev_handle) {
+		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev_handle);
 		if (!mp->m_rtdev_targp)
 			goto out_free_ddev_targ;
 	}
 
-	if (logdev && logdev != ddev) {
-		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev);
+	if (logdev_handle && logdev_handle->bdev != ddev) {
+		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev_handle);
 		if (!mp->m_logdev_targp)
 			goto out_free_rtdev_targ;
 	} else {
@@ -503,10 +507,10 @@ xfs_open_devices(
  out_free_ddev_targ:
 	xfs_free_buftarg(mp->m_ddev_targp);
  out_close_rtdev:
-	xfs_blkdev_put(mp, rtdev);
+	xfs_blkdev_put(rtdev_handle);
  out_close_logdev:
-	if (logdev && logdev != ddev)
-		xfs_blkdev_put(mp, logdev);
+	if (logdev_handle && logdev_handle->bdev != ddev)
+		xfs_blkdev_put(logdev_handle);
 	goto out_relock;
 }
 
-- 
2.35.3

[PATCH 29/29] block: Remove blkdev_get_by_*() functions

[Jan Kara]

blkdev_get_by_*() and blkdev_put() functions are now unused. Remove
them.

Signed-off-by: Jan Kara <jack@suse.cz>
---
 block/bdev.c           | 94 ++++++++++++++----------------------------
 include/linux/blkdev.h |  5 ---
 2 files changed, 30 insertions(+), 69 deletions(-)

diff --git a/block/bdev.c b/block/bdev.c
index 32c0ef5abad4..0e631c9a75aa 100644
--- a/block/bdev.c
+++ b/block/bdev.c
@@ -746,7 +746,7 @@ void blkdev_put_no_open(struct block_device *bdev)
 }
 	
 /**
- * blkdev_get_by_dev - open a block device by device number
+ * bdev_open_by_dev - open a block device by device number
  * @dev: device number of block device to open
  * @mode: open mode (BLK_OPEN_*)
  * @holder: exclusive holder identifier
@@ -758,32 +758,40 @@ void blkdev_put_no_open(struct block_device *bdev)
  *
  * Use this interface ONLY if you really do not have anything better - i.e. when
  * you are behind a truly sucky interface and all you are given is a device
- * number.  Everything else should use blkdev_get_by_path().
+ * number.  Everything else should use bdev_open_by_path().
  *
  * CONTEXT:
  * Might sleep.
  *
  * RETURNS:
- * Reference to the block_device on success, ERR_PTR(-errno) on failure.
+ * Handle with a reference to the block_device on success, ERR_PTR(-errno) on
+ * failure.
  */
-struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
-		const struct blk_holder_ops *hops)
+struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
+				     const struct blk_holder_ops *hops)
 {
-	bool unblock_events = true;
+	struct bdev_handle *handle = kmalloc(sizeof(struct bdev_handle),
+					     GFP_KERNEL);
 	struct block_device *bdev;
+	bool unblock_events = true;
 	struct gendisk *disk;
 	int ret;
 
+	if (!handle)
+		return ERR_PTR(-ENOMEM);
+
 	ret = devcgroup_check_permission(DEVCG_DEV_BLOCK,
 			MAJOR(dev), MINOR(dev),
 			((mode & BLK_OPEN_READ) ? DEVCG_ACC_READ : 0) |
 			((mode & BLK_OPEN_WRITE) ? DEVCG_ACC_WRITE : 0));
 	if (ret)
-		return ERR_PTR(ret);
+		goto free_handle;
 
 	bdev = blkdev_get_no_open(dev);
-	if (!bdev)
-		return ERR_PTR(-ENXIO);
+	if (!bdev) {
+		ret = -ENXIO;
+		goto free_handle;
+	}
 	disk = bdev->bd_disk;
 
 	if (holder) {
@@ -832,7 +840,10 @@ struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 
 	if (unblock_events)
 		disk_unblock_events(disk);
-	return bdev;
+	handle->bdev = bdev;
+	handle->holder = holder;
+	handle->mode = mode;
+	return handle;
 put_module:
 	module_put(disk->fops->owner);
 abort_claiming:
@@ -842,34 +853,14 @@ struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 	disk_unblock_events(disk);
 put_blkdev:
 	blkdev_put_no_open(bdev);
+free_handle:
+	kfree(handle);
 	return ERR_PTR(ret);
 }
-EXPORT_SYMBOL(blkdev_get_by_dev);
-
-struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
-				     const struct blk_holder_ops *hops)
-{
-	struct bdev_handle *handle = kmalloc(sizeof(*handle), GFP_KERNEL);
-	struct block_device *bdev;
-
-	if (!handle)
-		return ERR_PTR(-ENOMEM);
-	bdev = blkdev_get_by_dev(dev, mode, holder, hops);
-	if (IS_ERR(bdev)) {
-		kfree(handle);
-		return ERR_CAST(bdev);
-	}
-	handle->bdev = bdev;
-	handle->holder = holder;
-	if (holder)
-		mode |= BLK_OPEN_EXCL;
-	handle->mode = mode;
-	return handle;
-}
 EXPORT_SYMBOL(bdev_open_by_dev);
 
 /**
- * blkdev_get_by_path - open a block device by name
+ * bdev_open_by_path - open a block device by name
  * @path: path to the block device to open
  * @mode: open mode (BLK_OPEN_*)
  * @holder: exclusive holder identifier
@@ -883,29 +874,9 @@ EXPORT_SYMBOL(bdev_open_by_dev);
  * Might sleep.
  *
  * RETURNS:
- * Reference to the block_device on success, ERR_PTR(-errno) on failure.
+ * Handle with a reference to the block_device on success, ERR_PTR(-errno) on
+ * failure.
  */
-struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
-		void *holder, const struct blk_holder_ops *hops)
-{
-	struct block_device *bdev;
-	dev_t dev;
-	int error;
-
-	error = lookup_bdev(path, &dev);
-	if (error)
-		return ERR_PTR(error);
-
-	bdev = blkdev_get_by_dev(dev, mode, holder, hops);
-	if (!IS_ERR(bdev) && (mode & BLK_OPEN_WRITE) && bdev_read_only(bdev)) {
-		blkdev_put(bdev, holder);
-		return ERR_PTR(-EACCES);
-	}
-
-	return bdev;
-}
-EXPORT_SYMBOL(blkdev_get_by_path);
-
 struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
 		void *holder, const struct blk_holder_ops *hops)
 {
@@ -928,8 +899,9 @@ struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
 }
 EXPORT_SYMBOL(bdev_open_by_path);
 
-void blkdev_put(struct block_device *bdev, void *holder)
+void bdev_release(struct bdev_handle *handle)
 {
+	struct block_device *bdev = handle->bdev;
 	struct gendisk *disk = bdev->bd_disk;
 
 	/*
@@ -943,8 +915,8 @@ void blkdev_put(struct block_device *bdev, void *holder)
 		sync_blockdev(bdev);
 
 	mutex_lock(&disk->open_mutex);
-	if (holder)
-		bd_end_claim(bdev, holder);
+	if (handle->holder)
+		bd_end_claim(bdev, handle->holder);
 
 	/*
 	 * Trigger event checking and tell drivers to flush MEDIA_CHANGE
@@ -961,12 +933,6 @@ void blkdev_put(struct block_device *bdev, void *holder)
 
 	module_put(disk->fops->owner);
 	blkdev_put_no_open(bdev);
-}
-EXPORT_SYMBOL(blkdev_put);
-
-void bdev_release(struct bdev_handle *handle)
-{
-	blkdev_put(handle->bdev, handle->holder);
 	kfree(handle);
 }
 EXPORT_SYMBOL(bdev_release);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 0e89ad5c645c..28f78bdecae7 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1479,10 +1479,6 @@ struct bdev_handle {
 	blk_mode_t mode;
 };
 
-struct block_device *blkdev_get_by_dev(dev_t dev, blk_mode_t mode, void *holder,
-		const struct blk_holder_ops *hops);
-struct block_device *blkdev_get_by_path(const char *path, blk_mode_t mode,
-		void *holder, const struct blk_holder_ops *hops);
 struct bdev_handle *bdev_open_by_dev(dev_t dev, blk_mode_t mode, void *holder,
 		const struct blk_holder_ops *hops);
 struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
@@ -1490,7 +1486,6 @@ struct bdev_handle *bdev_open_by_path(const char *path, blk_mode_t mode,
 int bd_prepare_to_claim(struct block_device *bdev, void *holder,
 		const struct blk_holder_ops *hops);
 void bd_abort_claiming(struct block_device *bdev, void *holder);
-void blkdev_put(struct block_device *bdev, void *holder);
 void bdev_release(struct bdev_handle *handle);
 
 /* just for blk-cgroup, don't use elsewhere */
-- 
2.35.3

Re: [PATCH 02/29] block: Use bdev_open_by_dev() in blkdev_open()

[Christoph Hellwig]

On Fri, Aug 11, 2023 at 01:04:33PM +0200, Jan Kara wrote:
> +	blk_mode_t open_mode = ((struct bdev_handle *)file->private_data)->mode;

Nit: but I find it much more readable to just have a local bdev_handle
variable vs these deep references including casts.  This also appears
in a few others places.

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Christoph Hellwig]

Except for a mostly cosmetic nitpick this looks good to me:

Acked-by: Christoph Hellwig <hch@lst.de>

That's not eactly the deep review I'd like to do, but as I'm about to
head out for vacation that's probably as good as it gets.

Re: [PATCH 16/29] PM: hibernate: Convert to bdev_open_by_dev()

[Rafael J. Wysocki]

On Fri, Aug 11, 2023 at 1:05 PM Jan Kara <jack@suse.cz> wrote:
>
> Convert hibernation code to use bdev_open_by_dev().
>
> CC: linux-pm@vger.kernel.org
> Signed-off-by: Jan Kara <jack@suse.cz>

Acked-by: Rafael J. Wysocki <rafael@kernel.org>

> ---
>  kernel/power/swap.c | 31 ++++++++++++++++---------------
>  1 file changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/kernel/power/swap.c b/kernel/power/swap.c
> index f6ebcd00c410..b475bee282ff 100644
> --- a/kernel/power/swap.c
> +++ b/kernel/power/swap.c
> @@ -222,7 +222,7 @@ int swsusp_swap_in_use(void)
>   */
>
>  static unsigned short root_swap = 0xffff;
> -static struct block_device *hib_resume_bdev;
> +static struct bdev_handle *hib_resume_bdev_handle;
>
>  struct hib_bio_batch {
>         atomic_t                count;
> @@ -276,7 +276,8 @@ static int hib_submit_io(blk_opf_t opf, pgoff_t page_off, void *addr,
>         struct bio *bio;
>         int error = 0;
>
> -       bio = bio_alloc(hib_resume_bdev, 1, opf, GFP_NOIO | __GFP_HIGH);
> +       bio = bio_alloc(hib_resume_bdev_handle->bdev, 1, opf,
> +                       GFP_NOIO | __GFP_HIGH);
>         bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
>
>         if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
> @@ -356,14 +357,14 @@ static int swsusp_swap_check(void)
>                 return res;
>         root_swap = res;
>
> -       hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device,
> +       hib_resume_bdev_handle = bdev_open_by_dev(swsusp_resume_device,
>                         BLK_OPEN_WRITE, NULL, NULL);
> -       if (IS_ERR(hib_resume_bdev))
> -               return PTR_ERR(hib_resume_bdev);
> +       if (IS_ERR(hib_resume_bdev_handle))
> +               return PTR_ERR(hib_resume_bdev_handle);
>
> -       res = set_blocksize(hib_resume_bdev, PAGE_SIZE);
> +       res = set_blocksize(hib_resume_bdev_handle->bdev, PAGE_SIZE);
>         if (res < 0)
> -               blkdev_put(hib_resume_bdev, NULL);
> +               bdev_release(hib_resume_bdev_handle);
>
>         return res;
>  }
> @@ -1521,10 +1522,10 @@ int swsusp_check(bool snapshot_test)
>         void *holder = snapshot_test ? &swsusp_holder : NULL;
>         int error;
>
> -       hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, BLK_OPEN_READ,
> -                                           holder, NULL);
> -       if (!IS_ERR(hib_resume_bdev)) {
> -               set_blocksize(hib_resume_bdev, PAGE_SIZE);
> +       hib_resume_bdev_handle = bdev_open_by_dev(swsusp_resume_device,
> +                               BLK_OPEN_READ, holder, NULL);
> +       if (!IS_ERR(hib_resume_bdev_handle)) {
> +               set_blocksize(hib_resume_bdev_handle->bdev, PAGE_SIZE);
>                 clear_page(swsusp_header);
>                 error = hib_submit_io(REQ_OP_READ, swsusp_resume_block,
>                                         swsusp_header, NULL);
> @@ -1549,11 +1550,11 @@ int swsusp_check(bool snapshot_test)
>
>  put:
>                 if (error)
> -                       blkdev_put(hib_resume_bdev, holder);
> +                       bdev_release(hib_resume_bdev_handle);
>                 else
>                         pr_debug("Image signature found, resuming\n");
>         } else {
> -               error = PTR_ERR(hib_resume_bdev);
> +               error = PTR_ERR(hib_resume_bdev_handle);
>         }
>
>         if (error)
> @@ -1568,12 +1569,12 @@ int swsusp_check(bool snapshot_test)
>
>  void swsusp_close(bool snapshot_test)
>  {
> -       if (IS_ERR(hib_resume_bdev)) {
> +       if (IS_ERR(hib_resume_bdev_handle)) {
>                 pr_debug("Image device not initialised\n");
>                 return;
>         }
>
> -       blkdev_put(hib_resume_bdev, snapshot_test ? &swsusp_holder : NULL);
> +       bdev_release(hib_resume_bdev_handle);
>  }
>
>  /**
> --
> 2.35.3
>

Re: [PATCH 17/29] PM: hibernate: Drop unused snapshot_test argument

[Rafael J. Wysocki]

On Fri, Aug 11, 2023 at 1:05 PM Jan Kara <jack@suse.cz> wrote:
>
> snapshot_test argument is now unused in swsusp_close() and
> load_image_and_restore(). Drop it
>
> CC: linux-pm@vger.kernel.org
> Signed-off-by: Jan Kara <jack@suse.cz>

Acked-by: Rafael J. Wysocki <rafael@kernel.org>

> ---
>  kernel/power/hibernate.c | 14 +++++++-------
>  kernel/power/power.h     |  2 +-
>  kernel/power/swap.c      |  6 +++---
>  3 files changed, 11 insertions(+), 11 deletions(-)
>
> diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
> index e1b4bfa938dd..6abeec0ae084 100644
> --- a/kernel/power/hibernate.c
> +++ b/kernel/power/hibernate.c
> @@ -684,7 +684,7 @@ static void power_down(void)
>                 cpu_relax();
>  }
>
> -static int load_image_and_restore(bool snapshot_test)
> +static int load_image_and_restore(void)
>  {
>         int error;
>         unsigned int flags;
> @@ -694,12 +694,12 @@ static int load_image_and_restore(bool snapshot_test)
>         lock_device_hotplug();
>         error = create_basic_memory_bitmaps();
>         if (error) {
> -               swsusp_close(snapshot_test);
> +               swsusp_close();
>                 goto Unlock;
>         }
>
>         error = swsusp_read(&flags);
> -       swsusp_close(snapshot_test);
> +       swsusp_close();
>         if (!error)
>                 error = hibernation_restore(flags & SF_PLATFORM_MODE);
>
> @@ -788,7 +788,7 @@ int hibernate(void)
>                 pm_pr_dbg("Checking hibernation image\n");
>                 error = swsusp_check(snapshot_test);
>                 if (!error)
> -                       error = load_image_and_restore(snapshot_test);
> +                       error = load_image_and_restore();
>         }
>         thaw_processes();
>
> @@ -952,7 +952,7 @@ static int software_resume(void)
>         /* The snapshot device should not be opened while we're running */
>         if (!hibernate_acquire()) {
>                 error = -EBUSY;
> -               swsusp_close(false);
> +               swsusp_close();
>                 goto Unlock;
>         }
>
> @@ -973,7 +973,7 @@ static int software_resume(void)
>                 goto Close_Finish;
>         }
>
> -       error = load_image_and_restore(false);
> +       error = load_image_and_restore();
>         thaw_processes();
>   Finish:
>         pm_notifier_call_chain(PM_POST_RESTORE);
> @@ -987,7 +987,7 @@ static int software_resume(void)
>         pm_pr_dbg("Hibernation image not present or could not be loaded.\n");
>         return error;
>   Close_Finish:
> -       swsusp_close(false);
> +       swsusp_close();
>         goto Finish;
>  }
>
> diff --git a/kernel/power/power.h b/kernel/power/power.h
> index 46eb14dc50c3..bebf049a51c1 100644
> --- a/kernel/power/power.h
> +++ b/kernel/power/power.h
> @@ -172,7 +172,7 @@ int swsusp_check(bool snapshot_test);
>  extern void swsusp_free(void);
>  extern int swsusp_read(unsigned int *flags_p);
>  extern int swsusp_write(unsigned int flags);
> -void swsusp_close(bool snapshot_test);
> +void swsusp_close(void);
>  #ifdef CONFIG_SUSPEND
>  extern int swsusp_unmark(void);
>  #endif
> diff --git a/kernel/power/swap.c b/kernel/power/swap.c
> index b475bee282ff..17e0dad5008e 100644
> --- a/kernel/power/swap.c
> +++ b/kernel/power/swap.c
> @@ -444,7 +444,7 @@ static int get_swap_writer(struct swap_map_handle *handle)
>  err_rel:
>         release_swap_writer(handle);
>  err_close:
> -       swsusp_close(false);
> +       swsusp_close();
>         return ret;
>  }
>
> @@ -509,7 +509,7 @@ static int swap_writer_finish(struct swap_map_handle *handle,
>         if (error)
>                 free_all_swap_pages(root_swap);
>         release_swap_writer(handle);
> -       swsusp_close(false);
> +       swsusp_close();
>
>         return error;
>  }
> @@ -1567,7 +1567,7 @@ int swsusp_check(bool snapshot_test)
>   *     swsusp_close - close swap device.
>   */
>
> -void swsusp_close(bool snapshot_test)
> +void swsusp_close(void)
>  {
>         if (IS_ERR(hib_resume_bdev_handle)) {
>                 pr_debug("Image device not initialised\n");
> --
> 2.35.3
>

Re: [PATCH 11/29] md: Convert to bdev_open_by_dev()

[Song Liu]

On Fri, Aug 11, 2023 at 3:05 PM Jan Kara <jack@suse.cz> wrote:
[...]
> diff --git a/drivers/md/md.h b/drivers/md/md.h
> index 1aef86bf3fc3..e8108845157b 100644
> --- a/drivers/md/md.h
> +++ b/drivers/md/md.h
> @@ -59,6 +59,7 @@ struct md_rdev {
>          */
>         struct block_device *meta_bdev;
>         struct block_device *bdev;      /* block device handle */
> +       struct bdev_handle *bdev_handle;        /* Handle from open for bdev */

With bdev_handle, we should eventually get rid of md_rdev->bdev.
But that can be done in a separate patch.

Acked-by: Song Liu <song@kernel.org>

>
>         struct page     *sb_page, *bb_page;
>         int             sb_loaded;
> --
> 2.35.3
>

Re: [PATCH 28/29] xfs: Convert to bdev_open_by_path()

[Daniel Gomez]

Hi Jan,

On Fri, Aug 11, 2023 at 01:04:59PM +0200, Jan Kara wrote:
> Convert xfs to use bdev_open_by_path() and pass the handle around.
>
> CC: "Darrick J. Wong" <djwong@kernel.org>
> CC: linux-xfs@vger.kernel.org
> Signed-off-by: Jan Kara <jack@suse.cz>
> ---
>  fs/xfs/xfs_buf.c   | 11 +++++-----
>  fs/xfs/xfs_buf.h   |  3 ++-
>  fs/xfs/xfs_super.c | 54 +++++++++++++++++++++++++---------------------
>  3 files changed, 37 insertions(+), 31 deletions(-)
>
> diff --git a/fs/xfs/xfs_buf.c b/fs/xfs/xfs_buf.c
> index 15d1e5a7c2d3..461a5fb6155b 100644
> --- a/fs/xfs/xfs_buf.c
> +++ b/fs/xfs/xfs_buf.c
> @@ -1989,7 +1989,7 @@ xfs_setsize_buftarg_early(
>  struct xfs_buftarg *
>  xfs_alloc_buftarg(
>  	struct xfs_mount	*mp,
> -	struct block_device	*bdev)
> +	struct bdev_handle	*bdev_handle)
>  {
>  	xfs_buftarg_t		*btp;
>  	const struct dax_holder_operations *ops = NULL;
> @@ -2000,9 +2000,10 @@ xfs_alloc_buftarg(
>  	btp = kmem_zalloc(sizeof(*btp), KM_NOFS);
>
>  	btp->bt_mount = mp;
> -	btp->bt_dev =  bdev->bd_dev;
> -	btp->bt_bdev = bdev;
> -	btp->bt_daxdev = fs_dax_get_by_bdev(bdev, &btp->bt_dax_part_off,
> +	btp->bt_bdev_handle = bdev_handle;
> +	btp->bt_dev =  bdev_handle->bdev->bd_dev;
> +	btp->bt_bdev = bdev_handle->bdev;
> +	btp->bt_daxdev = fs_dax_get_by_bdev(btp->bt_bdev, &btp->bt_dax_part_off,
>  					    mp, ops);
>
>  	/*
> @@ -2012,7 +2013,7 @@ xfs_alloc_buftarg(
>  	ratelimit_state_init(&btp->bt_ioerror_rl, 30 * HZ,
>  			     DEFAULT_RATELIMIT_BURST);
>
> -	if (xfs_setsize_buftarg_early(btp, bdev))
> +	if (xfs_setsize_buftarg_early(btp, btp->bt_bdev))

This can now be simplified to one parameter. And use the btp->bt_bdev
directly when invoking bdev_logical_block_size.

>  		goto error_free;
>
>  	if (list_lru_init(&btp->bt_lru))
> diff --git a/fs/xfs/xfs_buf.h b/fs/xfs/xfs_buf.h
> index 549c60942208..f6418c1312f5 100644
> --- a/fs/xfs/xfs_buf.h
> +++ b/fs/xfs/xfs_buf.h
> @@ -92,6 +92,7 @@ typedef unsigned int xfs_buf_flags_t;
>   */
>  typedef struct xfs_buftarg {
>  	dev_t			bt_dev;
> +	struct bdev_handle	*bt_bdev_handle;
>  	struct block_device	*bt_bdev;
>  	struct dax_device	*bt_daxdev;
>  	u64			bt_dax_part_off;
> @@ -351,7 +352,7 @@ xfs_buf_update_cksum(struct xfs_buf *bp, unsigned long cksum_offset)
>   *	Handling of buftargs.
>   */
>  struct xfs_buftarg *xfs_alloc_buftarg(struct xfs_mount *mp,
> -		struct block_device *bdev);
> +		struct bdev_handle *bdev_handle);
>  extern void xfs_free_buftarg(struct xfs_buftarg *);
>  extern void xfs_buftarg_wait(struct xfs_buftarg *);
>  extern void xfs_buftarg_drain(struct xfs_buftarg *);
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 5340f2dc28bd..6189f726b309 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -381,14 +381,15 @@ STATIC int
>  xfs_blkdev_get(
>  	xfs_mount_t		*mp,
>  	const char		*name,
> -	struct block_device	**bdevp)
> +	struct bdev_handle	**handlep)
>  {
>  	int			error = 0;
>
> -	*bdevp = blkdev_get_by_path(name, BLK_OPEN_READ | BLK_OPEN_WRITE,
> -				    mp->m_super, &fs_holder_ops);
> -	if (IS_ERR(*bdevp)) {
> -		error = PTR_ERR(*bdevp);
> +	*handlep = bdev_open_by_path(name, BLK_OPEN_READ | BLK_OPEN_WRITE,
> +				     mp->m_super, &fs_holder_ops);
> +	if (IS_ERR(*handlep)) {
> +		error = PTR_ERR(*handlep);
> +		*handlep = NULL;
>  		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);
>  	}
>
> @@ -397,11 +398,10 @@ xfs_blkdev_get(
>
>  STATIC void
>  xfs_blkdev_put(
> -	struct xfs_mount	*mp,
> -	struct block_device	*bdev)
> +	struct bdev_handle	*handle)
>  {
> -	if (bdev)
> -		blkdev_put(bdev, mp->m_super);
> +	if (handle)
> +		bdev_release(handle);
>  }
>
>  STATIC void
> @@ -409,16 +409,18 @@ xfs_close_devices(
>  	struct xfs_mount	*mp)
>  {
>  	if (mp->m_logdev_targp && mp->m_logdev_targp != mp->m_ddev_targp) {
> -		struct block_device *logdev = mp->m_logdev_targp->bt_bdev;
> +		struct bdev_handle *logdev_handle =
> +			mp->m_logdev_targp->bt_bdev_handle;
>
>  		xfs_free_buftarg(mp->m_logdev_targp);
> -		xfs_blkdev_put(mp, logdev);
> +		xfs_blkdev_put(logdev_handle);
>  	}
>  	if (mp->m_rtdev_targp) {
> -		struct block_device *rtdev = mp->m_rtdev_targp->bt_bdev;
> +		struct bdev_handle *rtdev_handle =
> +			mp->m_rtdev_targp->bt_bdev_handle;
>
>  		xfs_free_buftarg(mp->m_rtdev_targp);
> -		xfs_blkdev_put(mp, rtdev);
> +		xfs_blkdev_put(rtdev_handle);
>  	}
>  	xfs_free_buftarg(mp->m_ddev_targp);
>  }
> @@ -439,7 +441,7 @@ xfs_open_devices(
>  {
>  	struct super_block	*sb = mp->m_super;
>  	struct block_device	*ddev = sb->s_bdev;
> -	struct block_device	*logdev = NULL, *rtdev = NULL;
> +	struct bdev_handle	*logdev_handle = NULL, *rtdev_handle = NULL;
>  	int			error;
>
>  	/*
> @@ -452,17 +454,19 @@ xfs_open_devices(
>  	 * Open real time and log devices - order is important.
>  	 */
>  	if (mp->m_logname) {
> -		error = xfs_blkdev_get(mp, mp->m_logname, &logdev);
> +		error = xfs_blkdev_get(mp, mp->m_logname, &logdev_handle);
>  		if (error)
>  			goto out_relock;
>  	}
>
>  	if (mp->m_rtname) {
> -		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev);
> +		error = xfs_blkdev_get(mp, mp->m_rtname, &rtdev_handle);
>  		if (error)
>  			goto out_close_logdev;
>
> -		if (rtdev == ddev || rtdev == logdev) {
> +		if (rtdev_handle->bdev == ddev ||
> +		    (logdev_handle &&
> +		     rtdev_handle->bdev == logdev_handle->bdev)) {
>  			xfs_warn(mp,
>  	"Cannot mount filesystem with identical rtdev and ddev/logdev.");
>  			error = -EINVAL;
> @@ -474,18 +478,18 @@ xfs_open_devices(
>  	 * Setup xfs_mount buffer target pointers
>  	 */
>  	error = -ENOMEM;
> -	mp->m_ddev_targp = xfs_alloc_buftarg(mp, ddev);
> +	mp->m_ddev_targp = xfs_alloc_buftarg(mp, sb->s_bdev_handle);
>  	if (!mp->m_ddev_targp)
>  		goto out_close_rtdev;
>
> -	if (rtdev) {
> -		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev);
> +	if (rtdev_handle) {
> +		mp->m_rtdev_targp = xfs_alloc_buftarg(mp, rtdev_handle);
>  		if (!mp->m_rtdev_targp)
>  			goto out_free_ddev_targ;
>  	}
>
> -	if (logdev && logdev != ddev) {
> -		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev);
> +	if (logdev_handle && logdev_handle->bdev != ddev) {
> +		mp->m_logdev_targp = xfs_alloc_buftarg(mp, logdev_handle);
>  		if (!mp->m_logdev_targp)
>  			goto out_free_rtdev_targ;
>  	} else {
> @@ -503,10 +507,10 @@ xfs_open_devices(
>   out_free_ddev_targ:
>  	xfs_free_buftarg(mp->m_ddev_targp);
>   out_close_rtdev:
> -	xfs_blkdev_put(mp, rtdev);
> +	xfs_blkdev_put(rtdev_handle);
>   out_close_logdev:
> -	if (logdev && logdev != ddev)
> -		xfs_blkdev_put(mp, logdev);
> +	if (logdev_handle && logdev_handle->bdev != ddev)
> +		xfs_blkdev_put(logdev_handle);
>  	goto out_relock;
>  }
>
> --
> 2.35.3
>

Re: [PATCH 11/29] md: Convert to bdev_open_by_dev()

[Jan Kara]

On Sun 13-08-23 19:54:56, Song Liu wrote:
> On Fri, Aug 11, 2023 at 3:05 PM Jan Kara <jack@suse.cz> wrote:
> [...]
> > diff --git a/drivers/md/md.h b/drivers/md/md.h
> > index 1aef86bf3fc3..e8108845157b 100644
> > --- a/drivers/md/md.h
> > +++ b/drivers/md/md.h
> > @@ -59,6 +59,7 @@ struct md_rdev {
> >          */
> >         struct block_device *meta_bdev;
> >         struct block_device *bdev;      /* block device handle */
> > +       struct bdev_handle *bdev_handle;        /* Handle from open for bdev */
> 
> With bdev_handle, we should eventually get rid of md_rdev->bdev.
> But that can be done in a separate patch.

Yeah, we can do that. But in the case of md it would cause a relatively
large amount of churn so at least for this series I've stayed with the
minimal solution.

> Acked-by: Song Liu <song@kernel.org>

Thanks!

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH 28/29] xfs: Convert to bdev_open_by_path()

[Jan Kara]

On Mon 14-08-23 10:27:46, Daniel Gomez wrote:
> 
> Hi Jan,
> 
> On Fri, Aug 11, 2023 at 01:04:59PM +0200, Jan Kara wrote:
> > Convert xfs to use bdev_open_by_path() and pass the handle around.
> >
> > CC: "Darrick J. Wong" <djwong@kernel.org>
> > CC: linux-xfs@vger.kernel.org
> > Signed-off-by: Jan Kara <jack@suse.cz>
...
> > @@ -2012,7 +2013,7 @@ xfs_alloc_buftarg(
> >  	ratelimit_state_init(&btp->bt_ioerror_rl, 30 * HZ,
> >  			     DEFAULT_RATELIMIT_BURST);
> >
> > -	if (xfs_setsize_buftarg_early(btp, bdev))
> > +	if (xfs_setsize_buftarg_early(btp, btp->bt_bdev))
> 
> This can now be simplified to one parameter. And use the btp->bt_bdev
> directly when invoking bdev_logical_block_size.

Fair point. Done.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH 02/29] block: Use bdev_open_by_dev() in blkdev_open()

[Jan Kara]

On Fri 11-08-23 05:25:41, Christoph Hellwig wrote:
> On Fri, Aug 11, 2023 at 01:04:33PM +0200, Jan Kara wrote:
> > +	blk_mode_t open_mode = ((struct bdev_handle *)file->private_data)->mode;
> 
> Nit: but I find it much more readable to just have a local bdev_handle
> variable vs these deep references including casts.  This also appears
> in a few others places.

OK, I've added the local variable to reduce typecasting and the depth of
dereferences.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH 09/29] bcache: Convert to bdev_open_by_path()

[Eric Wheeler]

On Fri, 11 Aug 2023, Jan Kara wrote:
> Convert bcache to use bdev_open_by_path() and pass the handle around.
> 
> CC: linux-bcache@vger.kernel.org
> CC: Coly Li <colyli@suse.de
> CC: Kent Overstreet <kent.overstreet@gmail.com>
> Acked-by: Coly Li <colyli@suse.de>
> Signed-off-by: Jan Kara <jack@suse.cz>
> ---
>  drivers/md/bcache/bcache.h |  2 +
>  drivers/md/bcache/super.c  | 78 ++++++++++++++++++++------------------
>  2 files changed, 43 insertions(+), 37 deletions(-)
> 
> diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
> index 5a79bb3c272f..2aa3f2c1f719 100644
> --- a/drivers/md/bcache/bcache.h
> +++ b/drivers/md/bcache/bcache.h
> @@ -299,6 +299,7 @@ struct cached_dev {
>  	struct list_head	list;
>  	struct bcache_device	disk;
>  	struct block_device	*bdev;
> +	struct bdev_handle	*bdev_handle;

It looks like you've handled most if not all of the `block_device *bdev` 
refactor.  Can we drop `block_device *bdev` and fixup any remaining 
references?  More below.

>  
>  	struct cache_sb		sb;
>  	struct cache_sb_disk	*sb_disk;
> @@ -421,6 +422,7 @@ struct cache {
>  
>  	struct kobject		kobj;
>  	struct block_device	*bdev;
> +	struct bdev_handle	*bdev_handle;

ditto.

>  
>  	struct task_struct	*alloc_thread;
>  
> diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> index 0ae2b3676293..c11ac86be72b 100644
> --- a/drivers/md/bcache/super.c
> +++ b/drivers/md/bcache/super.c
> @@ -1368,8 +1368,8 @@ static void cached_dev_free(struct closure *cl)
>  	if (dc->sb_disk)
>  		put_page(virt_to_page(dc->sb_disk));
>  
> -	if (!IS_ERR_OR_NULL(dc->bdev))
> -		blkdev_put(dc->bdev, dc);
> +	if (dc->bdev_handle)
> +		bdev_release(dc->bdev_handle);

bdev_release does not reset dc->bdev, which could leave a hanging 
reference.

>  
>  	wake_up(&unregister_wait);
>  
> @@ -1444,7 +1444,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
>  /* Cached device - bcache superblock */
>  
>  static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> -				 struct block_device *bdev,
> +				 struct bdev_handle *bdev_handle,
>  				 struct cached_dev *dc)
>  {
>  	const char *err = "cannot allocate memory";
> @@ -1452,14 +1452,15 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
>  	int ret = -ENOMEM;
>  
>  	memcpy(&dc->sb, sb, sizeof(struct cache_sb));
> -	dc->bdev = bdev;
> +	dc->bdev_handle = bdev_handle;
> +	dc->bdev = bdev_handle->bdev;

If I understand correctly, this patch duplicates the dc->bdev reference to 
exist as dc->bdev_handle->bdev _and_ dc->bdev. (Same for changes related 
to `struct cache`.)

This would mean future developers have to understand they are the same 
thing, and someone may not manage it correctly.

If block core is moving to `struct bdev_handle`, then can we drop 
`dc->bdev` and replace all occurances of `dc->bdev` with 
`bdev_handle->bdev`?  Or make an accessor macro/function like 
bdev_handle_get_bdev(dc->bdev_handle)?

Unless I misunderstand something here, I would NACK this as written 
because it increases the liklihood of future developer error.  

I've added a few other comments below, but my comments are not exhaustive:

>  	dc->sb_disk = sb_disk;
>  
>  	if (cached_dev_init(dc, sb->block_size << 9))
>  		goto err;
>  
>  	err = "error creating kobject";
> -	if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache"))
> +	if (kobject_add(&dc->disk.kobj, bdev_kobj(dc->bdev), "bcache"))
>  		goto err;
>  	if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
>  		goto err;
> @@ -2216,8 +2217,8 @@ void bch_cache_release(struct kobject *kobj)
>  	if (ca->sb_disk)
>  		put_page(virt_to_page(ca->sb_disk));
>  
> -	if (!IS_ERR_OR_NULL(ca->bdev))
> -		blkdev_put(ca->bdev, ca);
> +	if (ca->bdev_handle)
> +		bdev_release(ca->bdev_handle);
>  

ca->bdev is not cleaned up

>  	kfree(ca);
>  	module_put(THIS_MODULE);
> @@ -2337,16 +2338,18 @@ static int cache_alloc(struct cache *ca)
>  }
>  
>  static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> -				struct block_device *bdev, struct cache *ca)
> +				struct bdev_handle *bdev_handle,
> +				struct cache *ca)
>  {
>  	const char *err = NULL; /* must be set for any error case */
>  	int ret = 0;
>  
>  	memcpy(&ca->sb, sb, sizeof(struct cache_sb));
> -	ca->bdev = bdev;
> +	ca->bdev_handle = bdev_handle;
> +	ca->bdev = bdev_handle->bdev;
>  	ca->sb_disk = sb_disk;
>  
> -	if (bdev_max_discard_sectors((bdev)))
> +	if (bdev_max_discard_sectors((bdev_handle->bdev)))
>  		ca->discard = CACHE_DISCARD(&ca->sb);
>  
>  	ret = cache_alloc(ca);
> @@ -2354,10 +2357,10 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
>  		/*
>  		 * If we failed here, it means ca->kobj is not initialized yet,
>  		 * kobject_put() won't be called and there is no chance to
> -		 * call blkdev_put() to bdev in bch_cache_release(). So we
> -		 * explicitly call blkdev_put() here.
> +		 * call bdev_release() to bdev in bch_cache_release(). So
> +		 * we explicitly call bdev_release() here.
>  		 */
> -		blkdev_put(bdev, ca);
> +		bdev_release(bdev_handle);

ca->bdev is not cleaned up

>  		if (ret == -ENOMEM)
>  			err = "cache_alloc(): -ENOMEM";
>  		else if (ret == -EPERM)
> @@ -2367,7 +2370,7 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
>  		goto err;
>  	}
>  
> -	if (kobject_add(&ca->kobj, bdev_kobj(bdev), "bcache")) {
> +	if (kobject_add(&ca->kobj, bdev_kobj(bdev_handle->bdev), "bcache")) {
>  		err = "error calling kobject_add";
>  		ret = -ENOMEM;
>  		goto out;
> @@ -2382,14 +2385,14 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
>  		goto out;
>  	}
>  
> -	pr_info("registered cache device %pg\n", ca->bdev);
> +	pr_info("registered cache device %pg\n", ca->bdev_handle->bdev);
>  
>  out:
>  	kobject_put(&ca->kobj);
>  
>  err:
>  	if (err)
> -		pr_notice("error %pg: %s\n", ca->bdev, err);
> +		pr_notice("error %pg: %s\n", ca->bdev_handle->bdev, err);
>  
>  	return ret;
>  }
> @@ -2445,7 +2448,7 @@ struct async_reg_args {
>  	char *path;
>  	struct cache_sb *sb;
>  	struct cache_sb_disk *sb_disk;
> -	struct block_device *bdev;
> +	struct bdev_handle *bdev_handle;
>  	void *holder;
>  };
>  
> @@ -2456,8 +2459,8 @@ static void register_bdev_worker(struct work_struct *work)
>  		container_of(work, struct async_reg_args, reg_work.work);
>  
>  	mutex_lock(&bch_register_lock);
> -	if (register_bdev(args->sb, args->sb_disk, args->bdev, args->holder)
> -	    < 0)
> +	if (register_bdev(args->sb, args->sb_disk, args->bdev_handle,
> +			  args->holder) < 0)
>  		fail = true;
>  	mutex_unlock(&bch_register_lock);
>  
> @@ -2477,7 +2480,8 @@ static void register_cache_worker(struct work_struct *work)
>  		container_of(work, struct async_reg_args, reg_work.work);
>  
>  	/* blkdev_put() will be called in bch_cache_release() */
> -	if (register_cache(args->sb, args->sb_disk, args->bdev, args->holder))
> +	if (register_cache(args->sb, args->sb_disk, args->bdev_handle,
> +			   args->holder))
>  		fail = true;
>  
>  	if (fail)
> @@ -2514,7 +2518,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  	char *path = NULL;
>  	struct cache_sb *sb;
>  	struct cache_sb_disk *sb_disk;
> -	struct block_device *bdev, *bdev2;
> +	struct bdev_handle *bdev_handle, *bdev_handle2;
>  	void *holder = NULL;
>  	ssize_t ret;
>  	bool async_registration = false;
> @@ -2547,15 +2551,15 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  
>  	ret = -EINVAL;
>  	err = "failed to open device";
> -	bdev = blkdev_get_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
> -	if (IS_ERR(bdev))
> +	bdev_handle = bdev_open_by_path(strim(path), BLK_OPEN_READ, NULL, NULL);
> +	if (IS_ERR(bdev_handle))
>  		goto out_free_sb;
>  
>  	err = "failed to set blocksize";
> -	if (set_blocksize(bdev, 4096))
> +	if (set_blocksize(bdev_handle->bdev, 4096))
>  		goto out_blkdev_put;
>  
> -	err = read_super(sb, bdev, &sb_disk);
> +	err = read_super(sb, bdev_handle->bdev, &sb_disk);
>  	if (err)
>  		goto out_blkdev_put;
>  
> @@ -2567,13 +2571,13 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  	}
>  
>  	/* Now reopen in exclusive mode with proper holder */
> -	bdev2 = blkdev_get_by_dev(bdev->bd_dev, BLK_OPEN_READ | BLK_OPEN_WRITE,
> -				  holder, NULL);
> -	blkdev_put(bdev, NULL);
> -	bdev = bdev2;
> -	if (IS_ERR(bdev)) {
> -		ret = PTR_ERR(bdev);
> -		bdev = NULL;
> +	bdev_handle2 = bdev_open_by_dev(bdev_handle->bdev->bd_dev,
> +			BLK_OPEN_READ | BLK_OPEN_WRITE, holder, NULL);
> +	bdev_release(bdev_handle);
> +	bdev_handle = bdev_handle2;
> +	if (IS_ERR(bdev_handle)) {
> +		ret = PTR_ERR(bdev_handle);
> +		bdev_handle = NULL;
>  		if (ret == -EBUSY) {
>  			dev_t dev;
>  
> @@ -2608,7 +2612,7 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  		args->path	= path;
>  		args->sb	= sb;
>  		args->sb_disk	= sb_disk;
> -		args->bdev	= bdev;
> +		args->bdev_handle	= bdev_handle;
>  		args->holder	= holder;
>  		register_device_async(args);
>  		/* No wait and returns to user space */
> @@ -2617,14 +2621,14 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  
>  	if (SB_IS_BDEV(sb)) {
>  		mutex_lock(&bch_register_lock);
> -		ret = register_bdev(sb, sb_disk, bdev, holder);
> +		ret = register_bdev(sb, sb_disk, bdev_handle, holder);
>  		mutex_unlock(&bch_register_lock);
>  		/* blkdev_put() will be called in cached_dev_free() */
>  		if (ret < 0)
>  			goto out_free_sb;
>  	} else {
>  		/* blkdev_put() will be called in bch_cache_release() */
> -		ret = register_cache(sb, sb_disk, bdev, holder);
> +		ret = register_cache(sb, sb_disk, bdev_handle, holder);
>  		if (ret)
>  			goto out_free_sb;
>  	}
> @@ -2640,8 +2644,8 @@ static ssize_t register_bcache(struct kobject *k, struct kobj_attribute *attr,
>  out_put_sb_page:
>  	put_page(virt_to_page(sb_disk));
>  out_blkdev_put:
> -	if (bdev)
> -		blkdev_put(bdev, holder);
> +	if (bdev_handle)
> +		bdev_release(bdev_handle);
>  out_free_sb:
>  	kfree(sb);
>  out_free_path:
> -- 
> 2.35.3
> 
> 


--
Eric Wheeler

Re: [PATCH 09/29] bcache: Convert to bdev_open_by_path()

[Jan Kara]

On Sun 20-08-23 18:06:01, Eric Wheeler wrote:
> On Fri, 11 Aug 2023, Jan Kara wrote:
> > Convert bcache to use bdev_open_by_path() and pass the handle around.
> > 
> > CC: linux-bcache@vger.kernel.org
> > CC: Coly Li <colyli@suse.de
> > CC: Kent Overstreet <kent.overstreet@gmail.com>
> > Acked-by: Coly Li <colyli@suse.de>
> > Signed-off-by: Jan Kara <jack@suse.cz>
> > ---
> >  drivers/md/bcache/bcache.h |  2 +
> >  drivers/md/bcache/super.c  | 78 ++++++++++++++++++++------------------
> >  2 files changed, 43 insertions(+), 37 deletions(-)
> > 
> > diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
> > index 5a79bb3c272f..2aa3f2c1f719 100644
> > --- a/drivers/md/bcache/bcache.h
> > +++ b/drivers/md/bcache/bcache.h
> > @@ -299,6 +299,7 @@ struct cached_dev {
> >  	struct list_head	list;
> >  	struct bcache_device	disk;
> >  	struct block_device	*bdev;
> > +	struct bdev_handle	*bdev_handle;
> 
> It looks like you've handled most if not all of the `block_device *bdev` 
> refactor.  Can we drop `block_device *bdev` and fixup any remaining 
> references?  More below.

Well, we could but it's a lot of churn - like 53 dereferences in bcache.
So if bcache maintainer wants to go this way, sure we can do it. But
preferably as a separate cleanup patch on top of this series because the
series generates enough conflicts as is and this will make it considerably
worse.

> > @@ -421,6 +422,7 @@ struct cache {
> >  
> >  	struct kobject		kobj;
> >  	struct block_device	*bdev;
> > +	struct bdev_handle	*bdev_handle;
> 
> ditto.
> 
> >  
> >  	struct task_struct	*alloc_thread;
> >  
> > diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> > index 0ae2b3676293..c11ac86be72b 100644
> > --- a/drivers/md/bcache/super.c
> > +++ b/drivers/md/bcache/super.c
> > @@ -1368,8 +1368,8 @@ static void cached_dev_free(struct closure *cl)
> >  	if (dc->sb_disk)
> >  		put_page(virt_to_page(dc->sb_disk));
> >  
> > -	if (!IS_ERR_OR_NULL(dc->bdev))
> > -		blkdev_put(dc->bdev, dc);
> > +	if (dc->bdev_handle)
> > +		bdev_release(dc->bdev_handle);
> 
> bdev_release does not reset dc->bdev, which could leave a hanging 
> reference.

So after this, dc->bdev may reference freed block device that is true. But
the original code did not cleanup dc->bdev either so things just stay as
they were.

> > @@ -1444,7 +1444,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
> >  /* Cached device - bcache superblock */
> >  
> >  static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> > -				 struct block_device *bdev,
> > +				 struct bdev_handle *bdev_handle,
> >  				 struct cached_dev *dc)
> >  {
> >  	const char *err = "cannot allocate memory";
> > @@ -1452,14 +1452,15 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> >  	int ret = -ENOMEM;
> >  
> >  	memcpy(&dc->sb, sb, sizeof(struct cache_sb));
> > -	dc->bdev = bdev;
> > +	dc->bdev_handle = bdev_handle;
> > +	dc->bdev = bdev_handle->bdev;
> 
> If I understand correctly, this patch duplicates the dc->bdev reference to 
> exist as dc->bdev_handle->bdev _and_ dc->bdev. (Same for changes related 
> to `struct cache`.)

Well, dc->bdev isn't a reference anymore, just a shortcut so that people
don't have to write the long dc->bdev_handle->bdev (plus it limits the
churn this series generates as I've mentioned above). I can see why some
people needn't like this duplication so sure we can clean it up if that's
the concensus of bcache developers.
 
> This would mean future developers have to understand they are the same 
> thing, and someone may not manage it correctly.
> 
> If block core is moving to `struct bdev_handle`, then can we drop 
> `dc->bdev` and replace all occurances of `dc->bdev` with 
> `bdev_handle->bdev`?  Or make an accessor macro/function like 
> bdev_handle_get_bdev(dc->bdev_handle)?

Accessor is making things even longer and I don't see the benefit. So I'd
just go with dc->bdev_handle->bdev.

> Unless I misunderstand something here, I would NACK this as written 
> because it increases the liklihood of future developer error.  
> 
> I've added a few other comments below, but my comments are not exhaustive:
> 
> >  	dc->sb_disk = sb_disk;
> >  
> >  	if (cached_dev_init(dc, sb->block_size << 9))
> >  		goto err;
> >  
> >  	err = "error creating kobject";
> > -	if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache"))
> > +	if (kobject_add(&dc->disk.kobj, bdev_kobj(dc->bdev), "bcache"))
> >  		goto err;
> >  	if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
> >  		goto err;
> > @@ -2216,8 +2217,8 @@ void bch_cache_release(struct kobject *kobj)
> >  	if (ca->sb_disk)
> >  		put_page(virt_to_page(ca->sb_disk));
> >  
> > -	if (!IS_ERR_OR_NULL(ca->bdev))
> > -		blkdev_put(ca->bdev, ca);
> > +	if (ca->bdev_handle)
> > +		bdev_release(ca->bdev_handle);
> >  
> 
> ca->bdev is not cleaned up

Well, same comment as with dc->bdev - the old code didn't cleanup the
pointer either. Furthermore the structure is kfree()d in the line below so
there is really no point in zeroing the pointer.

> >  	kfree(ca);
> >  	module_put(THIS_MODULE);
> > @@ -2337,16 +2338,18 @@ static int cache_alloc(struct cache *ca)
> >  }
> >  
> >  static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> > -				struct block_device *bdev, struct cache *ca)
> > +				struct bdev_handle *bdev_handle,
> > +				struct cache *ca)
> >  {
> >  	const char *err = NULL; /* must be set for any error case */
> >  	int ret = 0;
> >  
> >  	memcpy(&ca->sb, sb, sizeof(struct cache_sb));
> > -	ca->bdev = bdev;
> > +	ca->bdev_handle = bdev_handle;
> > +	ca->bdev = bdev_handle->bdev;
> >  	ca->sb_disk = sb_disk;
> >  
> > -	if (bdev_max_discard_sectors((bdev)))
> > +	if (bdev_max_discard_sectors((bdev_handle->bdev)))
> >  		ca->discard = CACHE_DISCARD(&ca->sb);
> >  
> >  	ret = cache_alloc(ca);
> > @@ -2354,10 +2357,10 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> >  		/*
> >  		 * If we failed here, it means ca->kobj is not initialized yet,
> >  		 * kobject_put() won't be called and there is no chance to
> > -		 * call blkdev_put() to bdev in bch_cache_release(). So we
> > -		 * explicitly call blkdev_put() here.
> > +		 * call bdev_release() to bdev in bch_cache_release(). So
> > +		 * we explicitly call bdev_release() here.
> >  		 */
> > -		blkdev_put(bdev, ca);
> > +		bdev_release(bdev_handle);
> 
> ca->bdev is not cleaned up

So ca->bdev doesn't really need to be cleaned up here and the original code
wasn't cleaning it up either. So I don't see a problem here either... But
maybe I miss something.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH 09/29] bcache: Convert to bdev_open_by_path()

[Eric Wheeler]

On Mon, 21 Aug 2023, Jan Kara wrote:
> On Sun 20-08-23 18:06:01, Eric Wheeler wrote:
> > On Fri, 11 Aug 2023, Jan Kara wrote:
> > > Convert bcache to use bdev_open_by_path() and pass the handle around.
> > > 
> > > CC: linux-bcache@vger.kernel.org
> > > CC: Coly Li <colyli@suse.de
> > > CC: Kent Overstreet <kent.overstreet@gmail.com>
> > > Acked-by: Coly Li <colyli@suse.de>
> > > Signed-off-by: Jan Kara <jack@suse.cz>
> > > ---
> > >  drivers/md/bcache/bcache.h |  2 +
> > >  drivers/md/bcache/super.c  | 78 ++++++++++++++++++++------------------
> > >  2 files changed, 43 insertions(+), 37 deletions(-)
> > > 
> > > diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
> > > index 5a79bb3c272f..2aa3f2c1f719 100644
> > > --- a/drivers/md/bcache/bcache.h
> > > +++ b/drivers/md/bcache/bcache.h
> > > @@ -299,6 +299,7 @@ struct cached_dev {
> > >  	struct list_head	list;
> > >  	struct bcache_device	disk;
> > >  	struct block_device	*bdev;
> > > +	struct bdev_handle	*bdev_handle;
> > 
> > It looks like you've handled most if not all of the `block_device *bdev` 
> > refactor.  Can we drop `block_device *bdev` and fixup any remaining 
> > references?  More below.
> 
> Well, we could but it's a lot of churn - like 53 dereferences in bcache.
> So if bcache maintainer wants to go this way, sure we can do it. But
> preferably as a separate cleanup patch on top of this series because the
> series generates enough conflicts as is and this will make it considerably
> worse.

A separate cleanup patch seems reasonable, I'll defer to Coly on this one 
since he's the maintainer.  I just wanted to point out the possible issue.  
Thanks for your work on this.

--
Eric Wheeler



> 
> > > @@ -421,6 +422,7 @@ struct cache {
> > >  
> > >  	struct kobject		kobj;
> > >  	struct block_device	*bdev;
> > > +	struct bdev_handle	*bdev_handle;
> > 
> > ditto.
> > 
> > >  
> > >  	struct task_struct	*alloc_thread;
> > >  
> > > diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
> > > index 0ae2b3676293..c11ac86be72b 100644
> > > --- a/drivers/md/bcache/super.c
> > > +++ b/drivers/md/bcache/super.c
> > > @@ -1368,8 +1368,8 @@ static void cached_dev_free(struct closure *cl)
> > >  	if (dc->sb_disk)
> > >  		put_page(virt_to_page(dc->sb_disk));
> > >  
> > > -	if (!IS_ERR_OR_NULL(dc->bdev))
> > > -		blkdev_put(dc->bdev, dc);
> > > +	if (dc->bdev_handle)
> > > +		bdev_release(dc->bdev_handle);
> > 
> > bdev_release does not reset dc->bdev, which could leave a hanging 
> > reference.
> 
> So after this, dc->bdev may reference freed block device that is true. But
> the original code did not cleanup dc->bdev either so things just stay as
> they were.
> 
> > > @@ -1444,7 +1444,7 @@ static int cached_dev_init(struct cached_dev *dc, unsigned int block_size)
> > >  /* Cached device - bcache superblock */
> > >  
> > >  static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> > > -				 struct block_device *bdev,
> > > +				 struct bdev_handle *bdev_handle,
> > >  				 struct cached_dev *dc)
> > >  {
> > >  	const char *err = "cannot allocate memory";
> > > @@ -1452,14 +1452,15 @@ static int register_bdev(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> > >  	int ret = -ENOMEM;
> > >  
> > >  	memcpy(&dc->sb, sb, sizeof(struct cache_sb));
> > > -	dc->bdev = bdev;
> > > +	dc->bdev_handle = bdev_handle;
> > > +	dc->bdev = bdev_handle->bdev;
> > 
> > If I understand correctly, this patch duplicates the dc->bdev reference to 
> > exist as dc->bdev_handle->bdev _and_ dc->bdev. (Same for changes related 
> > to `struct cache`.)
> 
> Well, dc->bdev isn't a reference anymore, just a shortcut so that people
> don't have to write the long dc->bdev_handle->bdev (plus it limits the
> churn this series generates as I've mentioned above). I can see why some
> people needn't like this duplication so sure we can clean it up if that's
> the concensus of bcache developers.
>  
> > This would mean future developers have to understand they are the same 
> > thing, and someone may not manage it correctly.
> > 
> > If block core is moving to `struct bdev_handle`, then can we drop 
> > `dc->bdev` and replace all occurances of `dc->bdev` with 
> > `bdev_handle->bdev`?  Or make an accessor macro/function like 
> > bdev_handle_get_bdev(dc->bdev_handle)?
> 
> Accessor is making things even longer and I don't see the benefit. So I'd
> just go with dc->bdev_handle->bdev.
> 
> > Unless I misunderstand something here, I would NACK this as written 
> > because it increases the liklihood of future developer error.  
> > 
> > I've added a few other comments below, but my comments are not exhaustive:
> > 
> > >  	dc->sb_disk = sb_disk;
> > >  
> > >  	if (cached_dev_init(dc, sb->block_size << 9))
> > >  		goto err;
> > >  
> > >  	err = "error creating kobject";
> > > -	if (kobject_add(&dc->disk.kobj, bdev_kobj(bdev), "bcache"))
> > > +	if (kobject_add(&dc->disk.kobj, bdev_kobj(dc->bdev), "bcache"))
> > >  		goto err;
> > >  	if (bch_cache_accounting_add_kobjs(&dc->accounting, &dc->disk.kobj))
> > >  		goto err;
> > > @@ -2216,8 +2217,8 @@ void bch_cache_release(struct kobject *kobj)
> > >  	if (ca->sb_disk)
> > >  		put_page(virt_to_page(ca->sb_disk));
> > >  
> > > -	if (!IS_ERR_OR_NULL(ca->bdev))
> > > -		blkdev_put(ca->bdev, ca);
> > > +	if (ca->bdev_handle)
> > > +		bdev_release(ca->bdev_handle);
> > >  
> > 
> > ca->bdev is not cleaned up
> 
> Well, same comment as with dc->bdev - the old code didn't cleanup the
> pointer either. Furthermore the structure is kfree()d in the line below so
> there is really no point in zeroing the pointer.
> 
> > >  	kfree(ca);
> > >  	module_put(THIS_MODULE);
> > > @@ -2337,16 +2338,18 @@ static int cache_alloc(struct cache *ca)
> > >  }
> > >  
> > >  static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> > > -				struct block_device *bdev, struct cache *ca)
> > > +				struct bdev_handle *bdev_handle,
> > > +				struct cache *ca)
> > >  {
> > >  	const char *err = NULL; /* must be set for any error case */
> > >  	int ret = 0;
> > >  
> > >  	memcpy(&ca->sb, sb, sizeof(struct cache_sb));
> > > -	ca->bdev = bdev;
> > > +	ca->bdev_handle = bdev_handle;
> > > +	ca->bdev = bdev_handle->bdev;
> > >  	ca->sb_disk = sb_disk;
> > >  
> > > -	if (bdev_max_discard_sectors((bdev)))
> > > +	if (bdev_max_discard_sectors((bdev_handle->bdev)))
> > >  		ca->discard = CACHE_DISCARD(&ca->sb);
> > >  
> > >  	ret = cache_alloc(ca);
> > > @@ -2354,10 +2357,10 @@ static int register_cache(struct cache_sb *sb, struct cache_sb_disk *sb_disk,
> > >  		/*
> > >  		 * If we failed here, it means ca->kobj is not initialized yet,
> > >  		 * kobject_put() won't be called and there is no chance to
> > > -		 * call blkdev_put() to bdev in bch_cache_release(). So we
> > > -		 * explicitly call blkdev_put() here.
> > > +		 * call bdev_release() to bdev in bch_cache_release(). So
> > > +		 * we explicitly call bdev_release() here.
> > >  		 */
> > > -		blkdev_put(bdev, ca);
> > > +		bdev_release(bdev_handle);
> > 
> > ca->bdev is not cleaned up
> 
> So ca->bdev doesn't really need to be cleaned up here and the original code
> wasn't cleaning it up either. So I don't see a problem here either... But
> maybe I miss something.
> 
> 								Honza
> -- 
> Jan Kara <jack@suse.com>
> SUSE Labs, CR
> 

Re: [PATCH 09/29] bcache: Convert to bdev_open_by_path()

[Coly Li]

> 2023年8月22日 02:54，Eric Wheeler <bcache@lists.ewheeler.net> 写道：
> 
> On Mon, 21 Aug 2023, Jan Kara wrote:
>> On Sun 20-08-23 18:06:01, Eric Wheeler wrote:
>>> On Fri, 11 Aug 2023, Jan Kara wrote:
>>>> Convert bcache to use bdev_open_by_path() and pass the handle around.
>>>> 
>>>> CC: linux-bcache@vger.kernel.org
>>>> CC: Coly Li <colyli@suse.de
>>>> CC: Kent Overstreet <kent.overstreet@gmail.com>
>>>> Acked-by: Coly Li <colyli@suse.de>
>>>> Signed-off-by: Jan Kara <jack@suse.cz>
>>>> ---
>>>> drivers/md/bcache/bcache.h |  2 +
>>>> drivers/md/bcache/super.c  | 78 ++++++++++++++++++++------------------
>>>> 2 files changed, 43 insertions(+), 37 deletions(-)
>>>> 
>>>> diff --git a/drivers/md/bcache/bcache.h b/drivers/md/bcache/bcache.h
>>>> index 5a79bb3c272f..2aa3f2c1f719 100644
>>>> --- a/drivers/md/bcache/bcache.h
>>>> +++ b/drivers/md/bcache/bcache.h
>>>> @@ -299,6 +299,7 @@ struct cached_dev {
>>>> struct list_head list;
>>>> struct bcache_device disk;
>>>> struct block_device *bdev;
>>>> + struct bdev_handle *bdev_handle;
>>> 
>>> It looks like you've handled most if not all of the `block_device *bdev` 
>>> refactor.  Can we drop `block_device *bdev` and fixup any remaining 
>>> references?  More below.
>> 
>> Well, we could but it's a lot of churn - like 53 dereferences in bcache.
>> So if bcache maintainer wants to go this way, sure we can do it. But
>> preferably as a separate cleanup patch on top of this series because the
>> series generates enough conflicts as is and this will make it considerably
>> worse.
> 
> A separate cleanup patch seems reasonable, I'll defer to Coly on this one 
> since he's the maintainer.  I just wanted to point out the possible issue.  
> Thanks for your work on this.

Yes, the challenge of this series is from the block layer core, once the change in core part is accepted, the cleanup can be followed up if necessary.

Thank you all.

Coly Li

Re: [PATCH 02/29] block: Use bdev_open_by_dev() in blkdev_open()

[Al Viro]

On Fri, Aug 11, 2023 at 01:04:33PM +0200, Jan Kara wrote:

> @@ -478,7 +478,7 @@ blk_mode_t file_to_blk_mode(struct file *file)
>  		mode |= BLK_OPEN_READ;
>  	if (file->f_mode & FMODE_WRITE)
>  		mode |= BLK_OPEN_WRITE;
> -	if (file->private_data)
> +	if (file->f_flags & O_EXCL)
>  		mode |= BLK_OPEN_EXCL;
>  	if (file->f_flags & O_NDELAY)
>  		mode |= BLK_OPEN_NDELAY;


> index 3be11941fb2d..47f216d8697f 100644
> --- a/block/ioctl.c
> +++ b/block/ioctl.c
> @@ -575,7 +575,7 @@ long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
>  {
>  	struct block_device *bdev = I_BDEV(file->f_mapping->host);
>  	void __user *argp = (void __user *)arg;
> -	blk_mode_t mode = file_to_blk_mode(file);
> +	blk_mode_t mode = ((struct bdev_handle *)file->private_data)->mode;

Take a look at sd_ioctl() and note that fcntl(2) can be used to set/clear O_NDELAY.
The current variant works since we recalculate mode every time; this one will end up
stuck with whatever we had at open time.  Note that Christoph's series could do this
in blkdev_ioctl()
-       /*
-        * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
-        * to updated it before every ioctl.
-        */
-       if (file->f_flags & O_NDELAY)
-               mode |= FMODE_NDELAY;
-       else
-               mode &= ~FMODE_NDELAY;
precisely because his file_to_blk_mode() picks O_NDELAY from flags when blkdev_ioctl()
calls it.

The same goes for compat counterpart of that thing.  Both need to deal with that
scenario - you need something that would pick the O_NDELAY updates from ->f_flags.

Al, trying to catch up on the awful pile of mail that has accumulated over the 3 months
of being net.dead...

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Al Viro]

On Fri, Aug 11, 2023 at 01:04:31PM +0200, Jan Kara wrote:
> Hello,
> 
> this is a v2 of the patch series which implements the idea of blkdev_get_by_*()
> calls returning bdev_handle which is then passed to blkdev_put() [1]. This
> makes the get and put calls for bdevs more obviously matching and allows us to
> propagate context from get to put without having to modify all the users
> (again!).  In particular I need to propagate used open flags to blkdev_put() to
> be able count writeable opens and add support for blocking writes to mounted
> block devices. I'll send that series separately.
> 
> The series is based on Christian's vfs tree as of yesterday as there is quite
> some overlap. Patches have passed some reasonable testing - I've tested block
> changes, md, dm, bcache, xfs, btrfs, ext4, swap. This obviously doesn't cover
> everything so I'd like to ask respective maintainers to review / test their
> changes. Thanks! I've pushed out the full branch to:
> 
> git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git bdev_handle
> 
> to ease review / testing.

Hmm...  Completely Insane Idea(tm): how about turning that thing inside out and
having your bdev_open_by... return an actual opened struct file?

After all, we do that for sockets and pipes just fine and that's a whole lot
hotter area.

Suppose we leave blkdev_open()/blkdev_release() as-is.  No need to mess with
what we have for normal opened files for block devices.  And have block_open_by_dev()
that would find bdev, etc., same yours does and shove it into anon file.

Paired with plain fput() - no need to bother with new primitives for closing.
With a helper returning I_BDEV(bdev_file_inode(file)) to get from those to bdev.

NOTE: I'm not suggesting replacing ->s_bdev with struct file * if we do that -
we want that value cached, obviously.  Just store both...

Not saying it's a good idea, but... might be interesting to look into.
Comments?

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Jan Kara]

On Fri 25-08-23 02:58:43, Al Viro wrote:
> On Fri, Aug 11, 2023 at 01:04:31PM +0200, Jan Kara wrote:
> > Hello,
> > 
> > this is a v2 of the patch series which implements the idea of blkdev_get_by_*()
> > calls returning bdev_handle which is then passed to blkdev_put() [1]. This
> > makes the get and put calls for bdevs more obviously matching and allows us to
> > propagate context from get to put without having to modify all the users
> > (again!).  In particular I need to propagate used open flags to blkdev_put() to
> > be able count writeable opens and add support for blocking writes to mounted
> > block devices. I'll send that series separately.
> > 
> > The series is based on Christian's vfs tree as of yesterday as there is quite
> > some overlap. Patches have passed some reasonable testing - I've tested block
> > changes, md, dm, bcache, xfs, btrfs, ext4, swap. This obviously doesn't cover
> > everything so I'd like to ask respective maintainers to review / test their
> > changes. Thanks! I've pushed out the full branch to:
> > 
> > git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs.git bdev_handle
> > 
> > to ease review / testing.
> 
> Hmm...  Completely Insane Idea(tm): how about turning that thing inside out and
> having your bdev_open_by... return an actual opened struct file?
> 
> After all, we do that for sockets and pipes just fine and that's a whole lot
> hotter area.
> 
> Suppose we leave blkdev_open()/blkdev_release() as-is.  No need to mess with
> what we have for normal opened files for block devices.  And have block_open_by_dev()
> that would find bdev, etc., same yours does and shove it into anon file.
> 
> Paired with plain fput() - no need to bother with new primitives for closing.
> With a helper returning I_BDEV(bdev_file_inode(file)) to get from those to bdev.
> 
> NOTE: I'm not suggesting replacing ->s_bdev with struct file * if we do that -
> we want that value cached, obviously.  Just store both...
> 
> Not saying it's a good idea, but... might be interesting to look into.
> Comments?

I can see the appeal of not having to introduce the new bdev_handle type
and just using struct file which unifies in-kernel and userspace block
device opens. But I can see downsides too - the last fput() happening from
task work makes me a bit nervous whether it will not break something
somewhere with exclusive bdev opens. Getting from struct file to bdev is
somewhat harder but I guess a helper like F_BDEV() would solve that just
fine.

So besides my last fput() worry about I think this could work and would be
probably a bit nicer than what I have. But before going and redoing the whole
series let me gather some more feedback so that we don't go back and forth.
Christoph, Christian, Jens, any opinion?

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Al Viro]

On Fri, Aug 25, 2023 at 03:47:56PM +0200, Jan Kara wrote:

> I can see the appeal of not having to introduce the new bdev_handle type
> and just using struct file which unifies in-kernel and userspace block
> device opens. But I can see downsides too - the last fput() happening from
> task work makes me a bit nervous whether it will not break something
> somewhere with exclusive bdev opens. Getting from struct file to bdev is
> somewhat harder but I guess a helper like F_BDEV() would solve that just
> fine.
> 
> So besides my last fput() worry about I think this could work and would be
> probably a bit nicer than what I have. But before going and redoing the whole
> series let me gather some more feedback so that we don't go back and forth.
> Christoph, Christian, Jens, any opinion?

Redoing is not an issue - it can be done on top of your series just
as well.  Async behaviour of fput() might be, but...  need to look
through the actual users; for a lot of them it's perfectly fine.

FWIW, from a cursory look there appears to be a missing primitive: take
an opened bdev (or bdev_handle, with your variant, or opened file if we
go that way eventually) and claim it.

I mean, look at claim_swapfile() for example:
                p->bdev = blkdev_get_by_dev(inode->i_rdev,
                                   FMODE_READ | FMODE_WRITE | FMODE_EXCL, p);
                if (IS_ERR(p->bdev)) {
                        error = PTR_ERR(p->bdev);
                        p->bdev = NULL;
                        return error;
                }
                p->old_block_size = block_size(p->bdev);
                error = set_blocksize(p->bdev, PAGE_SIZE);
                if (error < 0)
                        return error;
we already have the file opened, and we keep it opened all the way until
the swapoff(2); here we have noticed that it's a block device and we
	* open the fucker again (by device number), this time claiming
it with our swap_info_struct as holder, to be closed at swapoff(2) time
(just before we close the file)
	* flip the block size to PAGE_SIZE, to be reverted at swapoff(2)
time That really looks like it ought to be
	* take the opened file, see that it's a block device
	* try to claim it with that holder
	* on success, flip the block size
with close_filp() in the swapoff(2) (or failure exit path in swapon(2))
doing what it would've done for an O_EXCL opened block device.
The only difference from O_EXCL userland open is that here we would
end up with holder pointing not to struct file in question, but to our
swap_info_struct.  It will do the right thing.

This extra open is entirely due to "well, we need to claim it and the
primitive that does that happens to be tied to opening"; feels rather
counter-intuitive.

For that matter, we could add an explicit "unclaim" primitive - might
be easier to follow.  That would add another example where that could
be used - in blkdev_bszset() we have an opened block device (it's an
ioctl, after all), we want to change block size and we *really* don't
want to have that happen under a mounted filesystem.  So if it's not
opened exclusive, we do a temporary exclusive open of own and act on
that instead.   Might as well go for a temporary claim...

BTW, what happens if two threads call ioctl(fd, BLKBSZSET, &n)
for the same descriptor that happens to have been opened O_EXCL?
Without O_EXCL they would've been unable to claim the sucker at the same
time - the holder we are using is the address of a function argument,
i.e. something that points to kernel stack of the caller.  Those would
conflict and we either get set_blocksize() calls fully serialized, or
one of the callers would eat -EBUSY.  Not so in "opened with O_EXCL"
case - they can very well overlap and IIRC set_blocksize() does *not*
expect that kind of crap...  It's all under CAP_SYS_ADMIN, so it's not
as if it was a meaningful security hole anyway, but it does look fishy.

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Christian Brauner]

> So besides my last fput() worry about I think this could work and would be
> probably a bit nicer than what I have. But before going and redoing the whole
> series let me gather some more feedback so that we don't go back and forth.
> Christoph, Christian, Jens, any opinion?

I'll be a bit under water for the next few days, I expect but I'll get
back to this. I think not making you redo this whole thing from scratch
is what I'd prefer unless there's really clear advantages. But I don't
want to offer a haphazard opinion in the middle of the merge window.

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Christoph Hellwig]

On Fri, Aug 25, 2023 at 03:47:56PM +0200, Jan Kara wrote:
> I can see the appeal of not having to introduce the new bdev_handle type
> and just using struct file which unifies in-kernel and userspace block
> device opens. But I can see downsides too - the last fput() happening from
> task work makes me a bit nervous whether it will not break something
> somewhere with exclusive bdev opens. Getting from struct file to bdev is
> somewhat harder but I guess a helper like F_BDEV() would solve that just
> fine.
> 
> So besides my last fput() worry about I think this could work and would be
> probably a bit nicer than what I have. But before going and redoing the whole
> series let me gather some more feedback so that we don't go back and forth.
> Christoph, Christian, Jens, any opinion?

I did think about the file a bit.  The fact that we'd need something
like an anon_file for the by_dev open was always a huge turn off for
me, but maybe my concern is overblown.  Having a struct file would
actually be really useful for a bunch of users.

Re: [PATCH v2 0/29] block: Make blkdev_get_by_*() return handle

[Christoph Hellwig]

On Sat, Aug 26, 2023 at 03:28:52AM +0100, Al Viro wrote:
> I mean, look at claim_swapfile() for example:
>                 p->bdev = blkdev_get_by_dev(inode->i_rdev,
>                                    FMODE_READ | FMODE_WRITE | FMODE_EXCL, p);
>                 if (IS_ERR(p->bdev)) {
>                         error = PTR_ERR(p->bdev);
>                         p->bdev = NULL;
>                         return error;
>                 }
>                 p->old_block_size = block_size(p->bdev);
>                 error = set_blocksize(p->bdev, PAGE_SIZE);
>                 if (error < 0)
>                         return error;
> we already have the file opened, and we keep it opened all the way until
> the swapoff(2); here we have noticed that it's a block device and we
> 	* open the fucker again (by device number), this time claiming
> it with our swap_info_struct as holder, to be closed at swapoff(2) time
> (just before we close the file)

Note that some drivers look at FMODE_EXCL/BLK_OPEN_EXCL in ->open.
These are probably bogus and maybe we want to kill them, but that will
need an audit first.

> BTW, what happens if two threads call ioctl(fd, BLKBSZSET, &n)
> for the same descriptor that happens to have been opened O_EXCL?
> Without O_EXCL they would've been unable to claim the sucker at the same
> time - the holder we are using is the address of a function argument,
> i.e. something that points to kernel stack of the caller.  Those would
> conflict and we either get set_blocksize() calls fully serialized, or
> one of the callers would eat -EBUSY.  Not so in "opened with O_EXCL"
> case - they can very well overlap and IIRC set_blocksize() does *not*
> expect that kind of crap...  It's all under CAP_SYS_ADMIN, so it's not
> as if it was a meaningful security hole anyway, but it does look fishy.

The user get to keep the pieces..  BLKBSZSET is kinda bogus anyway
as the soft blocksize only matters for buffer_head-like I/O, and
there only for file systems.  Not idea why anyone would set it manually.

[PATCH 19/29] fs: Convert to bdev_open_by_dev()

[Jan Kara]

Convert mount code to use bdev_open_by_dev() and propagate the handle
around to bdev_release().

Acked-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/cramfs/inode.c  |  2 +-
 fs/romfs/super.c   |  2 +-
 fs/super.c         | 15 +++++++++------
 include/linux/fs.h |  1 +
 4 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 5ee7d7bbb361..2fbf97077ce9 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -495,7 +495,7 @@ static void cramfs_kill_sb(struct super_block *sb)
 		sb->s_mtd = NULL;
 	} else if (IS_ENABLED(CONFIG_CRAMFS_BLOCKDEV) && sb->s_bdev) {
 		sync_blockdev(sb->s_bdev);
-		blkdev_put(sb->s_bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 	kfree(sbi);
 }
diff --git a/fs/romfs/super.c b/fs/romfs/super.c
index 5c35f6c76037..b1bdfbc211c3 100644
--- a/fs/romfs/super.c
+++ b/fs/romfs/super.c
@@ -593,7 +593,7 @@ static void romfs_kill_sb(struct super_block *sb)
 #ifdef CONFIG_ROMFS_ON_BLOCK
 	if (sb->s_bdev) {
 		sync_blockdev(sb->s_bdev);
-		blkdev_put(sb->s_bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 #endif
 }
diff --git a/fs/super.c b/fs/super.c
index 2d762ce67f6e..26b96191e9b3 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1479,14 +1479,16 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 		struct fs_context *fc)
 {
 	blk_mode_t mode = sb_open_mode(sb_flags);
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 
-	bdev = blkdev_get_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
+	if (IS_ERR(bdev_handle)) {
 		if (fc)
 			errorf(fc, "%s: Can't open blockdev", fc->source);
-		return PTR_ERR(bdev);
+		return PTR_ERR(bdev_handle);
 	}
+	bdev = bdev_handle->bdev;
 
 	/*
 	 * This really should be in blkdev_get_by_dev, but right now can't due
@@ -1494,7 +1496,7 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 	 * writable from userspace even for a read-only block device.
 	 */
 	if ((mode & BLK_OPEN_WRITE) && bdev_read_only(bdev)) {
-		blkdev_put(bdev, sb);
+		bdev_release(bdev_handle);
 		return -EACCES;
 	}
 
@@ -1510,10 +1512,11 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 		mutex_unlock(&bdev->bd_fsfreeze_mutex);
 		if (fc)
 			warnf(fc, "%pg: Can't mount, blockdev is frozen", bdev);
-		blkdev_put(bdev, sb);
+		bdev_release(bdev_handle);
 		return -EBUSY;
 	}
 	spin_lock(&sb_lock);
+	sb->s_bdev_handle = bdev_handle;
 	sb->s_bdev = bdev;
 	sb->s_bdi = bdi_get(bdev->bd_disk->bdi);
 	if (bdev_stable_writes(bdev))
@@ -1646,7 +1649,7 @@ void kill_block_super(struct super_block *sb)
 	generic_shutdown_super(sb);
 	if (bdev) {
 		sync_blockdev(bdev);
-		blkdev_put(bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 }
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index b528f063e8ff..03afc8b6f2af 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1221,6 +1221,7 @@ struct super_block {
 	struct hlist_bl_head	s_roots;	/* alternate root dentries for NFS */
 	struct list_head	s_mounts;	/* list of mounts; _not_ for fs use */
 	struct block_device	*s_bdev;
+	struct bdev_handle	*s_bdev_handle;
 	struct backing_dev_info *s_bdi;
 	struct mtd_info		*s_mtd;
 	struct hlist_node	s_instances;
-- 
2.35.3

Re: [PATCH 19/29] fs: Convert to bdev_open_by_dev()

[Christian Brauner]

On Wed, Aug 23, 2023 at 12:48:30PM +0200, Jan Kara wrote:
> Convert mount code to use bdev_open_by_dev() and propagate the handle
> around to bdev_release().
> 
> Acked-by: Christoph Hellwig <hch@lst.de>
> Signed-off-by: Jan Kara <jack@suse.cz>
> ---

Looks good to me,
Reviewed-by: Christian Brauner <brauner@kernel.org>

[PATCH 19/29] fs: Convert to bdev_open_by_dev()

[Jan Kara]

Convert mount code to use bdev_open_by_dev() and propagate the handle
around to bdev_release().

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
---
 fs/cramfs/inode.c  |  2 +-
 fs/romfs/super.c   |  2 +-
 fs/super.c         | 15 +++++++++------
 include/linux/fs.h |  1 +
 4 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 5ee7d7bbb361..2fbf97077ce9 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -495,7 +495,7 @@ static void cramfs_kill_sb(struct super_block *sb)
 		sb->s_mtd = NULL;
 	} else if (IS_ENABLED(CONFIG_CRAMFS_BLOCKDEV) && sb->s_bdev) {
 		sync_blockdev(sb->s_bdev);
-		blkdev_put(sb->s_bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 	kfree(sbi);
 }
diff --git a/fs/romfs/super.c b/fs/romfs/super.c
index 5c35f6c76037..b1bdfbc211c3 100644
--- a/fs/romfs/super.c
+++ b/fs/romfs/super.c
@@ -593,7 +593,7 @@ static void romfs_kill_sb(struct super_block *sb)
 #ifdef CONFIG_ROMFS_ON_BLOCK
 	if (sb->s_bdev) {
 		sync_blockdev(sb->s_bdev);
-		blkdev_put(sb->s_bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 #endif
 }
diff --git a/fs/super.c b/fs/super.c
index 1bea34be5d43..82757f3e0f1b 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1250,14 +1250,16 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 		struct fs_context *fc)
 {
 	blk_mode_t mode = sb_open_mode(sb_flags);
+	struct bdev_handle *bdev_handle;
 	struct block_device *bdev;
 
-	bdev = blkdev_get_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
-	if (IS_ERR(bdev)) {
+	bdev_handle = bdev_open_by_dev(sb->s_dev, mode, sb, &fs_holder_ops);
+	if (IS_ERR(bdev_handle)) {
 		if (fc)
 			errorf(fc, "%s: Can't open blockdev", fc->source);
-		return PTR_ERR(bdev);
+		return PTR_ERR(bdev_handle);
 	}
+	bdev = bdev_handle->bdev;
 
 	/*
 	 * This really should be in blkdev_get_by_dev, but right now can't due
@@ -1265,7 +1267,7 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 	 * writable from userspace even for a read-only block device.
 	 */
 	if ((mode & BLK_OPEN_WRITE) && bdev_read_only(bdev)) {
-		blkdev_put(bdev, sb);
+		bdev_release(bdev_handle);
 		return -EACCES;
 	}
 
@@ -1281,10 +1283,11 @@ int setup_bdev_super(struct super_block *sb, int sb_flags,
 		mutex_unlock(&bdev->bd_fsfreeze_mutex);
 		if (fc)
 			warnf(fc, "%pg: Can't mount, blockdev is frozen", bdev);
-		blkdev_put(bdev, sb);
+		bdev_release(bdev_handle);
 		return -EBUSY;
 	}
 	spin_lock(&sb_lock);
+	sb->s_bdev_handle = bdev_handle;
 	sb->s_bdev = bdev;
 	sb->s_bdi = bdi_get(bdev->bd_disk->bdi);
 	if (bdev_stable_writes(bdev))
@@ -1418,7 +1421,7 @@ void kill_block_super(struct super_block *sb)
 	generic_shutdown_super(sb);
 	if (bdev) {
 		sync_blockdev(bdev);
-		blkdev_put(bdev, sb);
+		bdev_release(sb->s_bdev_handle);
 	}
 }
 
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 22b59cd36963..b5c61107bd6d 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1187,6 +1187,7 @@ struct super_block {
 	struct hlist_bl_head	s_roots;	/* alternate root dentries for NFS */
 	struct list_head	s_mounts;	/* list of mounts; _not_ for fs use */
 	struct block_device	*s_bdev;
+	struct bdev_handle	*s_bdev_handle;
 	struct backing_dev_info *s_bdi;
 	struct mtd_info		*s_mtd;
 	struct hlist_node	s_instances;
-- 
2.35.3