[PATCH] r/o bind mounts: stub functions
commit8366025eb80dfa0d8d94b286d53027081c280ef1
authorDave Hansen <haveblue@us.ibm.com>
Fri, 15 Feb 2008 22:37:30 +0000 (15 14:37 -0800)
committerAl Viro <viro@zeniv.linux.org.uk>
Sat, 19 Apr 2008 04:25:32 +0000 (19 00:25 -0400)
tree052c9244cd9d763ad8467bb95b25d903d58b7f11
parenta70e65df8812c52252fa07a2eb92a46451a4427f
[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>
fs/namespace.c
include/linux/mount.h