bdev: add freeze and thaw holder operations

Add block device freeze and thaw holder operations. Follow-up patches
will implement block device freeze and thaw based on stuct
blk_holder_ops.

Link: https://lore.kernel.org/r/20231024-vfs-super-freeze-v2-4-599c19f4faac@kernel.org
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 7a3da7f44afb72fce2d58bd5dd7acb5468013129..1bc776335ff896c126f20adf1da92275599b12b5 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1468,6 +1468,16 @@ struct blk_holder_ops {
         * Sync the file system mounted on the block device.
         */
        void (*sync)(struct block_device *bdev);
+
+       /*
+        * Freeze the file system mounted on the block device.
+        */
+       int (*freeze)(struct block_device *bdev);
+
+       /*
+        * Thaw the file system mounted on the block device.
+        */
+       int (*thaw)(struct block_device *bdev);
 };
 
 extern const struct blk_holder_ops fs_holder_ops;