vfs: move ACL cache lookup into generic code

This moves logic for checking the cached ACL values from low-level
filesystems into generic code.  The end result is a streamlined ACL
check that doesn't need to load the inode->i_op->check_acl pointer at
all for the common cached case.

The filesystems also don't need to check for a non-blocking RCU walk
case in their acl_check() functions, because that is all handled at a
VFS layer.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 2 insertions, 6 deletions

diff --git a/fs/xfs/linux-2.6/xfs_acl.c b/fs/xfs/linux-2.6/xfs_acl.c
index cac48fe22ad5..f6d065ac56b5 100644
--- a/fs/xfs/linux-2.6/xfs_acl.c
+++ b/fs/xfs/linux-2.6/xfs_acl.c
@@ -231,16 +231,12 @@ xfs_check_acl(struct inode *inode, int mask)
         /*
          * If there is no attribute fork no ACL exists on this inode and
          * we can skip the whole exercise.
+         *
+         * FIXME! Fill the cache! Locking?
          */
         if (!XFS_IFORK_Q(ip))
                 return -EAGAIN;
 
-        if (mask & MAY_NOT_BLOCK) {
-                if (!negative_cached_acl(inode, ACL_TYPE_ACCESS))
-                        return -ECHILD;
-                return -EAGAIN;
-        }
-
         acl = xfs_get_acl(inode, ACL_TYPE_ACCESS);
         if (IS_ERR(acl))
                 return PTR_ERR(acl);