From: Jan Kara Subject: Re: [PATCH] mm: have filemap_check_and_advance_wb_err clear AS_EIO/AS_ENOSPC Date: Mon, 25 Sep 2017 10:17:48 +0200 Message-ID: <20170925081748.GA5741@quack2.suse.cz> References: <20170918112312.GN8034@eguan.usersys.redhat.com> <20170922133331.28812-1-jlayton@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linux-fsdevel@vger.kernel.org, Eryu Guan , Jan Kara , linux-ext4@vger.kernel.org To: Jeff Layton Return-path: Content-Disposition: inline In-Reply-To: <20170922133331.28812-1-jlayton@kernel.org> Sender: linux-fsdevel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org On Fri 22-09-17 09:33:31, Jeff Layton wrote: > From: Jeff Layton > > Eryu noticed that he could sometimes get a leftover error reported when > it shouldn't be on fsync with ext2 and non-journalled ext4. The problem > is that writeback_single_inode still uses filemap_fdatawait. That picks > up a previously set AS_EIO flag, which would ordinarily have been > cleared before. > > Since we're mostly using this function as a replacement for > filemap_check_errors, have filemap_check_and_advance_wb_err clear AS_EIO > and AS_ENOSPC when reporting an error. That should allow the new > function to better emulate the behavior of the old with respect to these > flags. > > Reported-by: Eryu Guan > Signed-off-by: Jeff Layton Looks good. You can add: Reviewed-by: Jan Kara Honza > --- > mm/filemap.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/mm/filemap.c b/mm/filemap.c > index 870971e20967..404722ea0fdd 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -620,6 +620,14 @@ int file_check_and_advance_wb_err(struct file *file) > trace_file_check_and_advance_wb_err(file, old); > spin_unlock(&file->f_lock); > } > + > + /* > + * We're mostly using this function as a drop in replacement for > + * filemap_check_errors. Clear AS_EIO/AS_ENOSPC to emulate the effect > + * that the legacy code would have had on these flags. > + */ > + clear_bit(AS_EIO, &mapping->flags); > + clear_bit(AS_ENOSPC, &mapping->flags); > return err; > } > EXPORT_SYMBOL(file_check_and_advance_wb_err); > -- > 2.13.5 > -- Jan Kara SUSE Labs, CR