diff options
| author | Dave Hansen <haveblue@us.ibm.com> | 2008-02-15 14:37:30 -0800 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2008-04-19 00:25:32 -0400 |
| commit | 8366025eb80dfa0d8d94b286d53027081c280ef1 (patch) | |
| tree | 052c9244cd9d763ad8467bb95b25d903d58b7f11 /include/linux/mount.h | |
| parent | a70e65df8812c52252fa07a2eb92a46451a4427f (diff) | |
[PATCH] r/o bind mounts: stub functions
This patch adds two function mnt_want_write() and mnt_drop_write(). These are
used like a lock pair around and fs operations that might cause a write to the
filesystem.
Before these can become useful, we must first cover each place in the VFS
where writes are performed with a want/drop pair. When that is complete, we
can actually introduce code that will safely check the counts before allowing
r/w<->r/o transitions to occur.
Acked-by: Serge Hallyn <serue@us.ibm.com>
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'include/linux/mount.h')
| -rw-r--r-- | include/linux/mount.h | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/include/linux/mount.h b/include/linux/mount.h index 5ee2df217cd..2eecd2c8c76 100644 --- a/include/linux/mount.h +++ b/include/linux/mount.h @@ -71,9 +71,12 @@ static inline struct vfsmount *mntget(struct vfsmount *mnt) return mnt; } +extern int mnt_want_write(struct vfsmount *mnt); +extern void mnt_drop_write(struct vfsmount *mnt); extern void mntput_no_expire(struct vfsmount *mnt); extern void mnt_pin(struct vfsmount *mnt); extern void mnt_unpin(struct vfsmount *mnt); +extern int __mnt_is_readonly(struct vfsmount *mnt); static inline void mntput(struct vfsmount *mnt) { |