[PATCH] r/o bind mounts: honor mount writer counts at remount

Originally from: Herbert Poetzl <[email protected]>

This is the core of the read-only bind mount patch set.

Note that this does _not_ add a "ro" option directly to the bind mount
operation.  If you require such a mount, you must first do the bind, then
follow it up with a 'mount -o remount,ro' operation:

If you wish to have a r/o bind mount of /foo on bar:

	mount --bind /foo /bar
	mount -o remount,ro /bar

Acked-by: Al Viro <[email protected]>
Signed-off-by: Christoph Hellwig <[email protected]>
Signed-off-by: Dave Hansen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Al Viro <[email protected]>
This commit is contained in:
Dave Hansen 2008-02-15 14:38:00 -08:00 • committed by Al Viro
commit 2e4b7fcd92
2 changed files with 44 additions and 7 deletions

View file

@ -29,6 +29,7 @@ struct mnt_namespace;
#define MNT_NOATIME 0x08
#define MNT_NODIRATIME 0x10
#define MNT_RELATIME 0x20
#define MNT_READONLY 0x40 /* does the user want this to be r/o? */
#define MNT_SHRINKABLE 0x100
#define MNT_IMBALANCED_WRITE_COUNT 0x200 /* just for debugging */