From: Eric Sandeen Subject: Re: [PATCH] ext4: sync the directory inode in ext4_sync_parent() Date: Tue, 05 Apr 2011 12:35:38 -0700 Message-ID: <4D9B6F0A.5080705@redhat.com> References: <1302031663-13547-1-git-send-email-curtw@google.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: tytso@mit.edu, linux-ext4@vger.kernel.org To: Curt Wohlgemuth Return-path: Received: from mx1.redhat.com ([209.132.183.28]:48356 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753709Ab1DETfm (ORCPT ); Tue, 5 Apr 2011 15:35:42 -0400 In-Reply-To: <1302031663-13547-1-git-send-email-curtw@google.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 4/5/11 12:27 PM, Curt Wohlgemuth wrote: > ext4 has taken the stance that, in the absence of a journal, > when an fsync/fdatasync of an inode is done, the parent > directory should be sync'ed if this inode entry is new. > ext4_sync_parent(), which implements this, does indeed sync > the dirent pages for parent directories, but it does not > sync the directory *inode*. This patch fixes this. > > I tested this using a power fail test, which panics a > machine running a file server getting requests from a > client. Without this patch, on about every other test run, > the server is missing many, many files that had been synced. > With this patch, on > 6 runs, I see zero files being lost. > > Signed-off-by: Curt Wohlgemuth > --- > fs/ext4/fsync.c | 11 ++++++++++- > 1 files changed, 10 insertions(+), 1 deletions(-) > > diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c > index 7f74019..a276348 100644 > --- a/fs/ext4/fsync.c > +++ b/fs/ext4/fsync.c > @@ -128,6 +128,7 @@ extern int ext4_flush_completed_IO(struct inode *inode) > static void ext4_sync_parent(struct inode *inode) > { > struct dentry *dentry = NULL; > + int ret; > > while (inode && ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) { > ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY); > @@ -136,7 +137,15 @@ static void ext4_sync_parent(struct inode *inode) > if (!dentry || !dentry->d_parent || !dentry->d_parent->d_inode) > break; > inode = dentry->d_parent->d_inode; > - sync_mapping_buffers(inode->i_mapping); > + ret = sync_mapping_buffers(inode->i_mapping); > + if (! ret) { > + struct writeback_control wbc = { > + .sync_mode = WB_SYNC_ALL, > + .nr_to_write = 0, /* metadata-only; caller > + takes care of data */ > + }; > + (void)sync_inode(inode, &wbc); I know ext4_sync_parent was a void already, but why don't we send errors back up through ext4_sync_file? -Eric > + } > } > } >