From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752557AbbCWCjl (ORCPT ); Sun, 22 Mar 2015 22:39:41 -0400 Received: from cantor2.suse.de ([195.135.220.15]:34536 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752530AbbCWCjf (ORCPT ); Sun, 22 Mar 2015 22:39:35 -0400 From: NeilBrown To: Al Viro Date: Mon, 23 Mar 2015 13:37:40 +1100 Subject: [PATCH 16/20] VFS/namei: enable RCU-walk when following symlinks. Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Message-ID: <20150323023740.8161.65198.stgit@notabene.brown> In-Reply-To: <20150323023258.8161.32467.stgit@notabene.brown> References: <20150323023258.8161.32467.stgit@notabene.brown> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that follow_link handles LOOKUP_RCU, we do not need to 'unlazy_walk' when a symlink is found. As we remain in RCU-walk mode, dentry->d_inode can change so the BUG_ON() assertions are no longer appropriate. Signed-off-by: NeilBrown --- fs/namei.c | 21 +++------------------ 1 file changed, 3 insertions(+), 18 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index 40ff4cb04244..0f5b627bd78e 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -1636,16 +1636,9 @@ static inline int walk_component(struct nameidata *nd, struct path *path, if (!inode || d_is_negative(path->dentry)) goto out_path_put; - if (should_follow_link(path->dentry, follow)) { - if (nd->flags & LOOKUP_RCU) { - if (unlikely(unlazy_walk(nd, path->dentry))) { - err = -ECHILD; - goto out_err; - } - } - BUG_ON(inode != path->dentry->d_inode); + if (should_follow_link(path->dentry, follow)) return 1; - } + path_to_nameidata(path, nd); nd->inode = inode; return 0; @@ -3102,16 +3095,8 @@ finish_lookup: goto out; } - if (should_follow_link(path->dentry, !symlink_ok)) { - if (nd->flags & LOOKUP_RCU) { - if (unlikely(unlazy_walk(nd, path->dentry))) { - error = -ECHILD; - goto out; - } - } - BUG_ON(inode != path->dentry->d_inode); + if (should_follow_link(path->dentry, !symlink_ok)) return 1; - } if ((nd->flags & LOOKUP_RCU) || nd->path.mnt != path->mnt) { path_to_nameidata(path, nd);