RCUify freeing acls, let check_acl() go ahead in RCU mode if acl is cached
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namei.c b/fs/namei.c
index 445fd5d..3d607bd 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -179,19 +179,14 @@
#ifdef CONFIG_FS_POSIX_ACL
struct posix_acl *acl;
- /*
- * Under RCU walk, we cannot even do a "get_cached_acl()",
- * because that involves locking and getting a refcount on
- * a cached ACL.
- *
- * So the only case we handle during RCU walking is the
- * case of a cached "no ACL at all", which needs no locks
- * or refcounts.
- */
if (mask & MAY_NOT_BLOCK) {
- if (negative_cached_acl(inode, ACL_TYPE_ACCESS))
+ acl = get_cached_acl_rcu(inode, ACL_TYPE_ACCESS);
+ if (!acl)
return -EAGAIN;
- return -ECHILD;
+ /* no ->get_acl() calls in RCU mode... */
+ if (acl == ACL_NOT_CACHED)
+ return -ECHILD;
+ return posix_acl_permission(inode, acl, mask);
}
acl = get_cached_acl(inode, ACL_TYPE_ACCESS);