]> git.baikalelectronics.ru Git - kernel.git/commit
[PATCH] namei fixes (9/19)
authorAl Viro <viro@www.linux.org.uk>
Mon, 6 Jun 2005 20:36:05 +0000 (13:36 -0700)
committerLinus Torvalds <torvalds@ppc970.osdl.org>
Mon, 6 Jun 2005 21:42:25 +0000 (14:42 -0700)
commit971aedb3c50f201f8ded35933bf9bd3cb8251105
treee5d9b39aca2a546bf2b832c5a2a7066e34f9c1b5
parent773a7a824e5d47997564b3845303fc2ec40c5f26
[PATCH] namei fixes (9/19)

New helper: __follow_mount(struct path *path).  Same as follow_mount(), except
that we do *not* do mntput() after the first lookup_mnt().

IOW, original path->mnt stays pinned down.  We also take care to do dput()
before mntput() in the loop body (follow_mount() also needs that reordering,
but that will be done later in the series).

The following are equivalent, assuming that path.mnt == x:
(1)
follow_mount(&path.mnt, &path.dentry)
(2)
__follow_mount(&path);
if (path->mnt != x)
mntput(x);
(3)
if (__follow_mount(&path))
mntput(x);

Callers of follow_mount() in __link_path_walk() converted to (2).

Equivalent transformation + fix for too-late-mntput() race in __follow_mount()
loop.

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
fs/namei.c