From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.fusionio.com ([66.114.96.30]:50539 "EHLO mx1.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751141Ab2GBMkE (ORCPT ); Mon, 2 Jul 2012 08:40:04 -0400 Date: Mon, 2 Jul 2012 08:40:02 -0400 From: Josef Bacik To: Miao Xie CC: Josef Bacik , "linux-btrfs@vger.kernel.org" Subject: Re: [PATCH] Btrfs: fix dio write vs buffered read race V3 Message-ID: <20120702124002.GA6185@localhost.localdomain> References: <1340888944-9471-1-git-send-email-jbacik@fusionio.com> <4FF027C4.30203@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" In-Reply-To: <4FF027C4.30203@cn.fujitsu.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Sun, Jul 01, 2012 at 04:34:44AM -0600, Miao Xie wrote: > On Thu, 28 Jun 2012 09:09:04 -0400, Josef Bacik wrote: > > fs/btrfs/file.c | 13 ------------ > > fs/btrfs/inode.c | 55 +++++++++++++++++++++++++++++++++++++++++++++++++---- > > 2 files changed, 50 insertions(+), 18 deletions(-) > > > > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > > index 70dc8ca..9aa01ec 100644 > > --- a/fs/btrfs/file.c > > +++ b/fs/btrfs/file.c > > @@ -1334,7 +1334,6 @@ static ssize_t __btrfs_direct_write(struct kiocb *iocb, > > loff_t *ppos, size_t count, size_t ocount) > > { > > struct file *file = iocb->ki_filp; > > - struct inode *inode = fdentry(file)->d_inode; > > struct iov_iter i; > > ssize_t written; > > ssize_t written_buffered; > > @@ -1344,18 +1343,6 @@ static ssize_t __btrfs_direct_write(struct kiocb *iocb, > > written = generic_file_direct_write(iocb, iov, &nr_segs, pos, ppos, > > count, ocount); > > > > - /* > > - * the generic O_DIRECT will update in-memory i_size after the > > - * DIOs are done. But our endio handlers that update the on > > - * disk i_size never update past the in memory i_size. So we > > - * need one more update here to catch any additions to the > > - * file > > - */ > > - if (inode->i_size != BTRFS_I(inode)->disk_i_size) { > > - btrfs_ordered_update_i_size(inode, inode->i_size, NULL); > > - mark_inode_dirty(inode); > > - } > > - > > if (written < 0 || written == count) > > return written; > > We should fall back the i_size in btrfs_direct_IO if we fails to do direct IO, right? > No we would have only updated the i_size in the case that we created new extents, we won't have i_size beyond where we have data. Thanks, Josef