block: introduce holder ops

Add a new blk_holder_ops structure, which is passed to blkdev_get_by_* and
installed in the block_device for exclusive claims.  It will be used to
allow the block layer to call back into the user of the block device for
thing like notification of a removed device or a device resize.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

12 files changed, 21 insertions, 18 deletions

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 78696d331639..4de4984fa99b 100644
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -258,7 +258,7 @@ static int btrfs_init_dev_replace_tgtdev(struct btrfs_fs_info *fs_info,
 	}
 
 	bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
-				  fs_info->bdev_holder);
+				  fs_info->bdev_holder, NULL);
 	if (IS_ERR(bdev)) {
 		btrfs_err(fs_info, "target device %s is invalid!", device_path);
 		return PTR_ERR(bdev);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 841e799dece5..784ccc8f6c69 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -496,7 +496,7 @@ btrfs_get_bdev_and_sb(const char *device_path, fmode_t flags, void *holder,
 {
 	int ret;
 
-	*bdev = blkdev_get_by_path(device_path, flags, holder);
+	*bdev = blkdev_get_by_path(device_path, flags, holder, NULL);
 
 	if (IS_ERR(*bdev)) {
 		ret = PTR_ERR(*bdev);
@@ -1377,7 +1377,7 @@ struct btrfs_device *btrfs_scan_one_device(const char *path, fmode_t flags,
 	 * values temporarily, as the device paths of the fsid are the only
 	 * required information for assembling the volume.
 	 */
-	bdev = blkdev_get_by_path(path, flags, holder);
+	bdev = blkdev_get_by_path(path, flags, holder, NULL);
 	if (IS_ERR(bdev))
 		return ERR_CAST(bdev);
 
@@ -2629,7 +2629,7 @@ int btrfs_init_new_device(struct btrfs_fs_info *fs_info, const char *device_path
 		return -EROFS;
 
 	bdev = blkdev_get_by_path(device_path, FMODE_WRITE | FMODE_EXCL,
-				  fs_info->bdev_holder);
+				  fs_info->bdev_holder, NULL);
 	if (IS_ERR(bdev))
 		return PTR_ERR(bdev);
 
diff --git a/fs/erofs/super.c b/fs/erofs/super.c
index 811ab66d805e..6c263e9cd38b 100644
--- a/fs/erofs/super.c
+++ b/fs/erofs/super.c
@@ -254,7 +254,7 @@ static int erofs_init_device(struct erofs_buf *buf, struct super_block *sb,
 		dif->fscache = fscache;
 	} else if (!sbi->devs->flatdev) {
 		bdev = blkdev_get_by_path(dif->path, FMODE_READ | FMODE_EXCL,
-					  sb->s_type);
+					  sb->s_type, NULL);
 		if (IS_ERR(bdev))
 			return PTR_ERR(bdev);
 		dif->bdev = bdev;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 9680fe753e59..865625089ecc 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1103,7 +1103,8 @@ static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 {
 	struct block_device *bdev;
 
-	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
+	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb,
+				 NULL);
 	if (IS_ERR(bdev))
 		goto fail;
 	return bdev;
diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index 9f15b03037db..7c34ab082f13 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -4025,7 +4025,7 @@ static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
 			/* Single zoned block device mount */
 			FDEV(0).bdev =
 				blkdev_get_by_dev(sbi->sb->s_bdev->bd_dev,
-					sbi->sb->s_mode, sbi->sb->s_type);
+					sbi->sb->s_mode, sbi->sb->s_type, NULL);
 		} else {
 			/* Multi-device mount */
 			memcpy(FDEV(i).path, RDEV(i).path, MAX_PATH_LEN);
@@ -4044,7 +4044,7 @@ static int f2fs_scan_devices(struct f2fs_sb_info *sbi)
 					sbi->log_blocks_per_seg) - 1;
 			}
 			FDEV(i).bdev = blkdev_get_by_path(FDEV(i).path,
-					sbi->sb->s_mode, sbi->sb->s_type);
+					sbi->sb->s_mode, sbi->sb->s_type, NULL);
 		}
 		if (IS_ERR(FDEV(i).bdev))
 			return PTR_ERR(FDEV(i).bdev);
diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
index 15c645827dec..46d393c8088a 100644
--- a/fs/jfs/jfs_logmgr.c
+++ b/fs/jfs/jfs_logmgr.c
@@ -1101,7 +1101,7 @@ int lmLogOpen(struct super_block *sb)
 	 */
 
 	bdev = blkdev_get_by_dev(sbi->logdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
-				 log);
+				 log, NULL);
 	if (IS_ERR(bdev)) {
 		rc = PTR_ERR(bdev);
 		goto free;
diff --git a/fs/nfs/blocklayout/dev.c b/fs/nfs/blocklayout/dev.c
index fea5f8821da5..38b066ca699e 100644
--- a/fs/nfs/blocklayout/dev.c
+++ b/fs/nfs/blocklayout/dev.c
@@ -243,7 +243,7 @@ bl_parse_simple(struct nfs_server *server, struct pnfs_block_dev *d,
 	if (!dev)
 		return -EIO;
 
-	bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL);
+	bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_WRITE, NULL, NULL);
 	if (IS_ERR(bdev)) {
 		printk(KERN_WARNING "pNFS: failed to open device %d:%d (%ld)\n",
 			MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
@@ -312,7 +312,8 @@ bl_open_path(struct pnfs_block_volume *v, const char *prefix)
 	if (!devname)
 		return ERR_PTR(-ENOMEM);
 
-	bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL);
+	bdev = blkdev_get_by_path(devname, FMODE_READ | FMODE_WRITE, NULL,
+				  NULL);
 	if (IS_ERR(bdev)) {
 		pr_warn("pNFS: failed to open device %s (%ld)\n",
 			devname, PTR_ERR(bdev));
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index 77f1e5778d1c..91bfbd973d1d 100644
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1285,7 +1285,7 @@ nilfs_mount(struct file_system_type *fs_type, int flags,
 	if (!(flags & SB_RDONLY))
 		mode |= FMODE_WRITE;
 
-	sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type);
+	sd.bdev = blkdev_get_by_path(dev_name, mode, fs_type, NULL);
 	if (IS_ERR(sd.bdev))
 		return ERR_CAST(sd.bdev);
 
diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c
index 60b97c92e2b2..6b13b8c3f2b8 100644
--- a/fs/ocfs2/cluster/heartbeat.c
+++ b/fs/ocfs2/cluster/heartbeat.c
@@ -1786,7 +1786,7 @@ static ssize_t o2hb_region_dev_store(struct config_item *item,
 		goto out2;
 
 	reg->hr_bdev = blkdev_get_by_dev(f.file->f_mapping->host->i_rdev,
-					 FMODE_WRITE | FMODE_READ, NULL);
+					 FMODE_WRITE | FMODE_READ, NULL, NULL);
 	if (IS_ERR(reg->hr_bdev)) {
 		ret = PTR_ERR(reg->hr_bdev);
 		reg->hr_bdev = NULL;
diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index 4d11d60f493c..5e4db9a0c8e5 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -2616,7 +2616,7 @@ static int journal_init_dev(struct super_block *super,
 		if (jdev == super->s_dev)
 			blkdev_mode &= ~FMODE_EXCL;
 		journal->j_dev_bd = blkdev_get_by_dev(jdev, blkdev_mode,
-						      journal);
+						      journal, NULL);
 		journal->j_dev_mode = blkdev_mode;
 		if (IS_ERR(journal->j_dev_bd)) {
 			result = PTR_ERR(journal->j_dev_bd);
@@ -2632,7 +2632,8 @@ static int journal_init_dev(struct super_block *super,
 	}
 
 	journal->j_dev_mode = blkdev_mode;
-	journal->j_dev_bd = blkdev_get_by_path(jdev_name, blkdev_mode, journal);
+	journal->j_dev_bd = blkdev_get_by_path(jdev_name, blkdev_mode, journal,
+					       NULL);
 	if (IS_ERR(journal->j_dev_bd)) {
 		result = PTR_ERR(journal->j_dev_bd);
 		journal->j_dev_bd = NULL;
diff --git a/fs/super.c b/fs/super.c
index 34afe411cf2b..012ce1400803 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1248,7 +1248,7 @@ int get_tree_bdev(struct fs_context *fc,
 	if (!fc->source)
 		return invalf(fc, "No source specified");
 
-	bdev = blkdev_get_by_path(fc->source, mode, fc->fs_type);
+	bdev = blkdev_get_by_path(fc->source, mode, fc->fs_type, NULL);
 	if (IS_ERR(bdev)) {
 		errorf(fc, "%s: Can't open blockdev", fc->source);
 		return PTR_ERR(bdev);
@@ -1333,7 +1333,7 @@ struct dentry *mount_bdev(struct file_system_type *fs_type,
 	if (!(flags & SB_RDONLY))
 		mode |= FMODE_WRITE;
 
-	bdev = blkdev_get_by_path(dev_name, mode, fs_type);
+	bdev = blkdev_get_by_path(dev_name, mode, fs_type, NULL);
 	if (IS_ERR(bdev))
 		return ERR_CAST(bdev);
 
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 7e706255f165..5684c538eb76 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -386,7 +386,7 @@ xfs_blkdev_get(
 	int			error = 0;
 
 	*bdevp = blkdev_get_by_path(name, FMODE_READ|FMODE_WRITE|FMODE_EXCL,
-				    mp);
+				    mp, NULL);
 	if (IS_ERR(*bdevp)) {
 		error = PTR_ERR(*bdevp);
 		xfs_warn(mp, "Invalid device [%s], error=%d", name, error);