From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Layton Subject: [PATCH v6 08/20] vfs: fix linkat to retry on ESTALE errors Date: Fri, 7 Sep 2012 10:18:15 -0400 Message-ID: <1347027507-20956-9-git-send-email-jlayton@redhat.com> References: <1347027507-20956-1-git-send-email-jlayton@redhat.com> Cc: linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, michael.brantley@deshaw.com, hch@infradead.org, miklos@szeredi.hu, pstaubach@exagrid.com To: viro@ZenIV.linux.org.uk Return-path: Received: from mail-vb0-f46.google.com ([209.85.212.46]:42139 "EHLO mail-vb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760696Ab2IGOSs (ORCPT ); Fri, 7 Sep 2012 10:18:48 -0400 Received: by mail-vb0-f46.google.com with SMTP id ff1so3363913vbb.19 for ; Fri, 07 Sep 2012 07:18:48 -0700 (PDT) In-Reply-To: <1347027507-20956-1-git-send-email-jlayton@redhat.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Signed-off-by: Jeff Layton --- fs/namei.c | 46 ++++++++++++++++++++++++++-------------------- 1 file changed, 26 insertions(+), 20 deletions(-) diff --git a/fs/namei.c b/fs/namei.c index ac731fc..e05d6ee 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -3612,6 +3612,7 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, struct path old_path, new_path; int how = 0; int error; + unsigned int try = 0; if ((flags & ~(AT_SYMLINK_FOLLOW | AT_EMPTY_PATH)) != 0) return -EINVAL; @@ -3629,30 +3630,35 @@ SYSCALL_DEFINE5(linkat, int, olddfd, const char __user *, oldname, if (flags & AT_SYMLINK_FOLLOW) how |= LOOKUP_FOLLOW; - error = user_path_at(olddfd, oldname, how, &old_path); - if (error) - return error; + do { + error = user_path_at(olddfd, oldname, how, &old_path); + if (error) + break; - new_dentry = user_path_create(newdfd, newname, &new_path, false, false); - error = PTR_ERR(new_dentry); - if (IS_ERR(new_dentry)) - goto out; + new_dentry = user_path_create(newdfd, newname, &new_path, + false, false); + error = PTR_ERR(new_dentry); + if (IS_ERR(new_dentry)) + goto out; - error = -EXDEV; - if (old_path.mnt != new_path.mnt) - goto out_dput; - error = may_linkat(&old_path); - if (unlikely(error)) - goto out_dput; - error = security_path_link(old_path.dentry, &new_path, new_dentry); - if (error) - goto out_dput; - error = vfs_link(old_path.dentry, new_path.dentry->d_inode, new_dentry); + error = -EXDEV; + if (old_path.mnt != new_path.mnt) + goto out_dput; + error = may_linkat(&old_path); + if (unlikely(error)) + goto out_dput; + error = security_path_link(old_path.dentry, &new_path, + new_dentry); + if (error) + goto out_dput; + error = vfs_link(old_path.dentry, new_path.dentry->d_inode, + new_dentry); out_dput: - done_path_create(&new_path, new_dentry); + done_path_create(&new_path, new_dentry); out: - path_put(&old_path); - + path_put(&old_path); + how |= LOOKUP_REVAL; + } while (retry_estale(error, try++)); return error; } -- 1.7.11.4