default_acl and acl of newly created inode will be initiated as
ACL_NOT_CACHED in vfs function inode_init_always() and later will be
updated by calling xxx_init_acl() in specific filesystems.  However,
when default_acl and acl are NULL then they keep the value of
ACL_NOT_CACHED.  This patch changes the code to cache NULL for acl /
default_acl in this case to save unnecessary ACL lookup attempt.
Signed-off-by: Chengguang Xu <cgxu519@gmx.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
                error = __ext4_set_acl(handle, inode, ACL_TYPE_DEFAULT,
                                       default_acl, XATTR_CREATE);
                posix_acl_release(default_acl);
+       } else {
+               inode->i_default_acl = NULL;
        }
        if (acl) {
                if (!error)
                        error = __ext4_set_acl(handle, inode, ACL_TYPE_ACCESS,
                                               acl, XATTR_CREATE);
                posix_acl_release(acl);
+       } else {
+               inode->i_acl = NULL;
        }
        return error;
 }