diff options
author | Dave Hansen <haveblue@us.ibm.com> | 2008-02-15 22:37:48 (GMT) |
---|---|---|
committer | Al Viro <viro@zeniv.linux.org.uk> | 2008-04-19 04:29:25 (GMT) |
commit | 4a3fd211ccfc08a88edc824300e25a87785c6a5f (patch) | |
tree | 99f1a76a99fa78464b8de731f7fdb5bcc9667a5e /virt | |
parent | 42a74f206b914db13ee1f5ae932dcd91a77c8579 (diff) | |
download | linux-4a3fd211ccfc08a88edc824300e25a87785c6a5f.tar.xz |
[PATCH] r/o bind mounts: elevate write count for open()s
This is the first really tricky patch in the series. It elevates the writer
count on a mount each time a non-special file is opened for write.
We used to do this in may_open(), but Miklos pointed out that __dentry_open()
is used as well to create filps. This will cover even those cases, while a
call in may_open() would not have.
There is also an elevated count around the vfs_create() call in open_namei().
See the comments for more details, but we need this to fix a 'create, remount,
fail r/w open()' race.
Some filesystems forego the use of normal vfs calls to create
struct files. Make sure that these users elevate the mnt
writer count because they will get __fput(), and we need
to make sure they're balanced.
Acked-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'virt')
0 files changed, 0 insertions, 0 deletions