fs: add a method to shut down the file system

Add a new ->shutdown super operation that can be used to tell the file
system to shut down, and call it from newly created holder ops when the
block device under a file system shuts down.

This only covers the main block device for "simple" file systems using
get_tree_bdev / mount_bdev.  File systems their own get_tree method
or opening additional devices will need to set up their own
blk_holder_ops.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Link: https://lore.kernel.org/r/20230601094459.1350643-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2023-06-01 11:44:54 +02:00 committed by Jens Axboe
parent f55e017c64
commit 87efb39075
2 changed files with 20 additions and 2 deletions

View file

@ -1206,6 +1206,22 @@ int get_tree_keyed(struct fs_context *fc,
EXPORT_SYMBOL(get_tree_keyed);
#ifdef CONFIG_BLOCK
static void fs_mark_dead(struct block_device *bdev)
{
struct super_block *sb;
sb = get_super(bdev);
if (!sb)
return;
if (sb->s_op->shutdown)
sb->s_op->shutdown(sb);
drop_super(sb);
}
static const struct blk_holder_ops fs_holder_ops = {
.mark_dead = fs_mark_dead,
};
static int set_bdev_super(struct super_block *s, void *data)
{
@ -1248,7 +1264,8 @@ 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, NULL);
bdev = blkdev_get_by_path(fc->source, mode, fc->fs_type,
&fs_holder_ops);
if (IS_ERR(bdev)) {
errorf(fc, "%s: Can't open blockdev", fc->source);
return PTR_ERR(bdev);
@ -1333,7 +1350,7 @@ 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, NULL);
bdev = blkdev_get_by_path(dev_name, mode, fs_type, &fs_holder_ops);
if (IS_ERR(bdev))
return ERR_CAST(bdev);

View file

@ -1932,6 +1932,7 @@ struct super_operations {
struct shrink_control *);
long (*free_cached_objects)(struct super_block *,
struct shrink_control *);
void (*shutdown)(struct super_block *sb);
};
/*