It is OK to let access() go without using a mnt_want/drop_write()
pair because it doesn't actually do writes to the filesystem,
and it is inherently racy anyway.  This is a rare case when it is
OK to use __mnt_is_readonly() directly.

Signed-off-by: Dave Hansen <[EMAIL PROTECTED]>
---

 lxc-dave/fs/open.c |   13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff -puN fs/open.c~make-access-use-helper fs/open.c
--- lxc/fs/open.c~make-access-use-helper        2007-07-10 12:46:07.000000000 
-0700
+++ lxc-dave/fs/open.c  2007-07-10 12:46:07.000000000 -0700
@@ -396,8 +396,17 @@ asmlinkage long sys_faccessat(int dfd, c
        if(res || !(mode & S_IWOTH) ||
           special_file(nd.dentry->d_inode->i_mode))
                goto out_path_release;
-
-       if(IS_RDONLY(nd.dentry->d_inode))
+       /*
+        * This is a rare case where using __mnt_is_readonly()
+        * is OK without a mnt_want/drop_write() pair.  Since
+        * no actual write to the fs is performed here, we do
+        * not need to telegraph to that to anyone.
+        *
+        * By doing this, we accept that this access is
+        * inherently racy and know that the fs may change
+        * state before we even see this result.
+        */
+       if (__mnt_is_readonly(nd.mnt))
                res = -EROFS;
 
 out_path_release:
_
-
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