Commit 69881be3 authored by Christian Brauner's avatar Christian Brauner
Browse files

fs: export sget_dev() 



They will be used for mtd devices as well.

Acked-by: default avatarRichard Weinberger <richard@nod.at>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Message-Id: <20230829-vfs-super-mtd-v1-1-fecb572e5df3@kernel.org>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarChristian Brauner <brauner@kernel.org>
parent b97d64c7

fs/super.c

+45 −19
Original line number Diff line number Diff line
@@ -1373,6 +1373,50 @@ int get_tree_keyed(struct fs_context *fc, 
}

EXPORT_SYMBOL(get_tree_keyed);



static int set_bdev_super(struct super_block *s, void *data)

{

	s->s_dev = *(dev_t *)data;

	return 0;

}



static int super_s_dev_set(struct super_block *s, struct fs_context *fc)

{

	return set_bdev_super(s, fc->sget_key);

}



static int super_s_dev_test(struct super_block *s, struct fs_context *fc)

{

	return !(s->s_iflags & SB_I_RETIRED) &&

		s->s_dev == *(dev_t *)fc->sget_key;

}



/**

 * sget_dev - Find or create a superblock by device number

 * @fc: Filesystem context.

 * @dev: device number

 *

 * Find or create a superblock using the provided device number that

 * will be stored in fc->sget_key.

 *

 * If an extant superblock is matched, then that will be returned with

 * an elevated reference count that the caller must transfer or discard.

 *

 * If no match is made, a new superblock will be allocated and basic

 * initialisation will be performed (s_type, s_fs_info, s_id, s_dev will

 * be set). The superblock will be published and it will be returned in

 * a partially constructed state with SB_BORN and SB_ACTIVE as yet

 * unset.

 *

 * Return: an existing or newly created superblock on success, an error

 *         pointer on failure.

 */

struct super_block *sget_dev(struct fs_context *fc, dev_t dev)

{

	fc->sget_key = &dev;

	return sget_fc(fc, super_s_dev_test, super_s_dev_set);

}

EXPORT_SYMBOL(sget_dev);



#ifdef CONFIG_BLOCK

/*

 * Lock a super block that the callers holds a reference to.
@@ -1431,23 +1475,6 @@ const struct blk_holder_ops fs_holder_ops = { 
};

EXPORT_SYMBOL_GPL(fs_holder_ops);



static int set_bdev_super(struct super_block *s, void *data)

{

	s->s_dev = *(dev_t *)data;

	return 0;

}



static int set_bdev_super_fc(struct super_block *s, struct fs_context *fc)

{

	return set_bdev_super(s, fc->sget_key);

}



static int test_bdev_super_fc(struct super_block *s, struct fs_context *fc)

{

	return !(s->s_iflags & SB_I_RETIRED) &&

		s->s_dev == *(dev_t *)fc->sget_key;

}



int setup_bdev_super(struct super_block *sb, int sb_flags,

		struct fs_context *fc)

{
@@ -1525,8 +1552,7 @@ int get_tree_bdev(struct fs_context *fc, 
	}



	fc->sb_flags |= SB_NOSEC;

	fc->sget_key = &dev;

	s = sget_fc(fc, test_bdev_super_fc, set_bdev_super_fc);

	s = sget_dev(fc, dev);

	if (IS_ERR(s))

		return PTR_ERR(s);

include/linux/fs.h

+1 −0
Original line number Diff line number Diff line
@@ -2397,6 +2397,7 @@ struct super_block *sget(struct file_system_type *type, 
			int (*test)(struct super_block *,void *),

			int (*set)(struct super_block *,void *),

			int flags, void *data);

struct super_block *sget_dev(struct fs_context *fc, dev_t dev);



/* Alas, no aliases. Too much hassle with bringing module.h everywhere */

#define fops_get(fops) \