From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from plane.gmane.org ([80.91.229.3]:47718 "EHLO plane.gmane.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933262AbaKMRn0 (ORCPT ); Thu, 13 Nov 2014 12:43:26 -0500 Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1XoyQW-0007RV-0Y for linux-btrfs@vger.kernel.org; Thu, 13 Nov 2014 18:43:24 +0100 Received: from pd953e883.dip0.t-ipconnect.de ([217.83.232.131]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 13 Nov 2014 18:43:24 +0100 Received: from holger.hoffstaette by pd953e883.dip0.t-ipconnect.de with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 13 Nov 2014 18:43:24 +0100 To: linux-btrfs@vger.kernel.org From: Holger =?iso-8859-1?q?Hoffst=E4tte?= Subject: Re: [PATCH] Btrfs: don't ignore log btree writeback errors Date: Thu, 13 Nov 2014 17:43:12 +0000 (UTC) Message-ID: References: <1415897993-7556-1-git-send-email-fdmanana@suse.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Thu, 13 Nov 2014 17:33:19 +0000, Holger Hoffstätte wrote: > On Thu, 13 Nov 2014 16:59:53 +0000, Filipe Manana wrote: > >> If an error happens during writeback of log btree extents, make sure the >> error is returned to the caller (fsync), so that it takes proper action >> (commit current transaction) instead of writing a superblock that points >> to log btrees with all or some nodes that weren't durably persisted. >> >> Signed-off-by: Filipe Manana >> --- >> fs/btrfs/tree-log.c | 21 +++++++++++++++------ >> 1 file changed, 15 insertions(+), 6 deletions(-) >> >> diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c >> index 6d58d72..c8274d3 100644 >> --- a/fs/btrfs/tree-log.c >> +++ b/fs/btrfs/tree-log.c >> @@ -2599,12 +2599,14 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans, >> index2 = root_log_ctx.log_transid % 2; >> if (atomic_read(&log_root_tree->log_commit[index2])) { >> blk_finish_plug(&plug); >> - btrfs_wait_marked_extents(log, &log->dirty_log_pages, mark); >> + ret = btrfs_wait_marked_extents(log, &log->dirty_log_pages, >> + mark); >> wait_log_commit(trans, log_root_tree, >> root_log_ctx.log_transid); >> btrfs_free_logged_extents(log, log_transid); >> mutex_unlock(&log_root_tree->log_mutex); >> - ret = root_log_ctx.log_ret; >> + if (!ret) >> + ret = root_log_ctx.log_ret; >> goto out; >> } >> ASSERT(root_log_ctx.log_transid == log_root_tree->log_transid); > > This first hunk didn't apply to my 3.14.x tree that is 99.999% in sync with > btrfs-3.18+, as a line is missing from the context. See: > > https://git.kernel.org/cgit/linux/kernel/git/mason/linux-btrfs.git/tree/fs/btrfs/tree-log.c?h=for-linus#n2605 > > Any idea where that missing btrfs_free_logged_extents() went? Found it: it went away with Josef's recent patch on Nov 6: "Btrfs: make sure we wait on logged extents when fsycning two subvols" (http://permalink.gmane.org/gmane.comp.file-systems.btrfs/40005) ..which I have applied. boohoo. That patch also adds another call to btrfs_wait_marked_extents(), which should then probably also have its return value handled? thanks, Holger