From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753906AbYE1Iqi (ORCPT ); Wed, 28 May 2008 04:46:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751170AbYE1Iq3 (ORCPT ); Wed, 28 May 2008 04:46:29 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:33553 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750854AbYE1Iq3 (ORCPT ); Wed, 28 May 2008 04:46:29 -0400 Date: Wed, 28 May 2008 01:46:15 -0700 From: Andrew Morton To: Dave Chinner Cc: Guillaume Chazarain , linux-kernel@vger.kernel.org Subject: Re: [PATCH] fs-writeback: handle errors in sync_sb_inodes() Message-Id: <20080528014615.2583e8dc.akpm@linux-foundation.org> In-Reply-To: <20080528084313.GE3819@disturbed> References: <20080523203429.11846.84137.stgit@localhost.localdomain> <20080527223832.f7131761.akpm@linux-foundation.org> <20080528082550.GD3819@disturbed> <20080528013549.9636349c.akpm@linux-foundation.org> <20080528084313.GE3819@disturbed> X-Mailer: Sylpheed 2.4.8 (GTK+ 2.12.5; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 28 May 2008 18:43:13 +1000 Dave Chinner wrote: > On Wed, May 28, 2008 at 01:35:49AM -0700, Andrew Morton wrote: > > On Wed, 28 May 2008 18:25:50 +1000 Dave Chinner wrote: > > > On Tue, May 27, 2008 at 10:38:32PM -0700, Andrew Morton wrote: > > > > On Fri, 23 May 2008 22:34:29 +0200 Guillaume Chazarain wrote: > > > > > diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c > > > > > index 495214d..0e6881e 100644 > > > > > --- a/fs/fs-writeback.c > > > > > +++ b/fs/fs-writeback.c > > > > > @@ -454,6 +454,7 @@ void generic_sync_sb_inodes(struct super_block *sb, > > > > > struct address_space *mapping = inode->i_mapping; > > > > > struct backing_dev_info *bdi = mapping->backing_dev_info; > > > > > long pages_skipped; > > > > > + int err; > > > > > > > > > > if (!bdi_cap_writeback_dirty(bdi)) { > > > > > redirty_tail(inode); > > > > > @@ -498,7 +499,8 @@ void generic_sync_sb_inodes(struct super_block *sb, > > > > > BUG_ON(inode->i_state & I_FREEING); > > > > > __iget(inode); > > > > > pages_skipped = wbc->pages_skipped; > > > > > - __writeback_single_inode(inode, wbc); > > > > > + err = __writeback_single_inode(inode, wbc); > > > > > + mapping_set_error(mapping, err); > > > > > if (wbc->sync_mode == WB_SYNC_HOLD) { > > > > > inode->dirtied_when = jiffies; > > > > > list_move(&inode->i_list, &sb->s_dirty); > > > > > > > > ho hum, I've forgotten why I didn't like this. Let's give it a run. > > > > > > IIRC, it'll produce lots of spurious EIO errors under writeback on > > > XFS as XFS will return EAGAIN if we've been asked for a non-blocking > > > flush and we would have blocked.... > > > > OIC. This, I guess... > > > > --- a/fs/fs-writeback.c~fs-writeback-handle-errors-in-sync_sb_inodes-fix > > +++ a/fs/fs-writeback.c > > @@ -500,7 +500,8 @@ void generic_sync_sb_inodes(struct super > > __iget(inode); > > pages_skipped = wbc->pages_skipped; > > err = __writeback_single_inode(inode, wbc); > > - mapping_set_error(mapping, err); > > + if (err == -EIO || err == -ENOSPC) /* xfs can return -EAGAIN */ > > + mapping_set_error(mapping, err); > > Rapidly gets messy. XFS can also return at least EDQUOT and EUCLEAN > (i.e. EFSCORRUPTED) from here as well, and it's likely that there's > other real errors I can't think of right now as well. > argh. Who said it was allowed to do that :( Give up. We (ie: I) need to fix this one properly.