vfs: Add a single-or-reconfig keying to vfs_get_super()
Add an additional keying mode to vfs_get_super() to indicate that only a
single superblock should exist in the system, and that, if it does, further
mounts should invoke reconfiguration upon it.
This allows mount_single() to be replaced.
[Fix by Eric Biggers folded in]
Signed-off-by: David Howells <[email protected]>
Signed-off-by: Al Viro <[email protected]>
diff --git a/include/linux/fs_context.h b/include/linux/fs_context.h
index 84a5eaa..0424df7 100644
--- a/include/linux/fs_context.h
+++ b/include/linux/fs_context.h
@@ -141,6 +141,7 @@ extern void put_fs_context(struct fs_context *fc);
*/
enum vfs_get_super_keying {
vfs_get_single_super, /* Only one such superblock may exist */
+ vfs_get_single_reconf_super, /* As above, but reconfigure if it exists */
vfs_get_keyed_super, /* Superblocks with different s_fs_info keys may exist */
vfs_get_independent_super, /* Multiple independent superblocks may exist */
};
@@ -155,6 +156,9 @@ extern int get_tree_nodev(struct fs_context *fc,
extern int get_tree_single(struct fs_context *fc,
int (*fill_super)(struct super_block *sb,
struct fs_context *fc));
+extern int get_tree_single_reconf(struct fs_context *fc,
+ int (*fill_super)(struct super_block *sb,
+ struct fs_context *fc));
extern int get_tree_keyed(struct fs_context *fc,
int (*fill_super)(struct super_block *sb,
struct fs_context *fc),
