On Wed 11-05-11 11:19:01, Darrick J. Wong wrote: > On Tue, May 10, 2011 at 02:51:24PM +0200, Jan Kara wrote: > > On Mon 09-05-11 16:03:18, Darrick J. Wong wrote: > > > I am still chasing down what exactly is broken in ext3. data=writeback mode > > > passes with no failures. data=ordered, however, does not pass; my current > > > suspicion is that jbd is calling submit_bh on data buffers but doesn't call > > > page_mkclean to kick the userspace programs off the page before writing it. > > Yes, ext3 in data=ordered mode writes pages from > > journal_commit_transaction() via submit_bh() without clearing page dirty > > bits thus page_mkclean() is not called for these pages. Frankly, do you > > really want to bother with adding support for ext2 and ext3? People can use > > ext4 as a fs driver when they want to start using blk-integrity support. > > Especially ext2 patch looks really painful and just from a quick look I can > > see code e.g. in fs/ext2/namei.c which isn't handled by your patch yet. > > Yeah, I agree that ext2 is ugly and ext3/jbd might be more painful. Are there > any other code that wants stable pages that's already running with ext3? In > this months-long discussion I've heard that encryption and raid also like > stable pages during writes. Have those users been broken this whole time, or > have they been stabilizing pages themselves? I believe part of them has been broken (e.g. raid) and part of them do copy-out so they were OK. > I suppose we can cross the "ext3 fails horribly on DIF" bridge when someone > complains about it. Possibly we could try to steer them to btrfs. Well, btrfs might be a bit too advantageous for production servers but ext4 would be definitely viable for them. Honza -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>