fs: take the ACL checks to common code

Replace the ->check_acl method with a ->get_acl method that simply reads an
ACL from disk after having a cache miss.  This means we can replace the ACL
checking boilerplate code with a single implementation in namei.c.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ext2/acl.c b/fs/ext2/acl.c
index ba99fa4..52c0537 100644
--- a/fs/ext2/acl.c
+++ b/fs/ext2/acl.c
@@ -128,7 +128,7 @@
 /*
  * inode->i_mutex: don't care
  */
-static struct posix_acl *
+struct posix_acl *
 ext2_get_acl(struct inode *inode, int type)
 {
 	int name_index;
@@ -231,23 +231,6 @@
 	return error;
 }
 
-int
-ext2_check_acl(struct inode *inode, int mask)
-{
-	struct posix_acl *acl;
-
-	acl = ext2_get_acl(inode, ACL_TYPE_ACCESS);
-	if (IS_ERR(acl))
-		return PTR_ERR(acl);
-	if (acl) {
-		int error = posix_acl_permission(inode, acl, mask);
-		posix_acl_release(acl);
-		return error;
-	}
-
-	return -EAGAIN;
-}
-
 /*
  * Initialize the ACLs of a new inode. Called from ext2_new_inode.
  *