[dm-devel] [PATCH v2] dm: gracefully fail any request beyond the end of the device
Mike Snitzer
snitzer at redhat.com
Mon Sep 24 13:07:11 UTC 2012
On Mon, Sep 24 2012 at 5:38am -0400,
Jun'ichi Nomura <j-nomura at ce.jp.nec.com> wrote:
> On 09/22/12 00:47, Mike Snitzer wrote:
> > @@ -1651,19 +1654,31 @@ static void dm_request_fn(struct request
> > if (!rq)
> > goto delay_and_out;
> >
> > + clone = rq->special;
> > +
> > /* always use block 0 to find the target for flushes for now */
> > pos = 0;
> > if (!(rq->cmd_flags & REQ_FLUSH))
> > pos = blk_rq_pos(rq);
> >
> > ti = dm_table_find_target(map, pos);
> > - BUG_ON(!dm_target_is_valid(ti));
> > + if (!dm_target_is_valid(ti)) {
> > + /*
> > + * Must perform setup, that dm_done() requires,
> > + * before calling dm_kill_unmapped_request
> > + */
> > + DMERR_LIMIT("request attempted access beyond the end of device");
> > + blk_start_request(rq);
> > + atomic_inc(&md->pending[rq_data_dir(clone)]);
> > + dm_get(md);
> > + dm_kill_unmapped_request(clone, -EIO);
> > + goto out;
>
> This "goto out" should be "continue" so that request_fn
> process next requests in the queue.
>
> Also I think introducing a function dm_start_request()
> will make this part of code a little bit easier for reading.
> An edited patch is attached.
Aside from the continue, matches exactly what I was going to do for v3
(based on Mike Christie's feedback -- which was to introduce
dm_start_request too). Anyway, looks great.
I'll get a formal v3 posted so Alasdair can stage it.
Thanks,
Mike
More information about the dm-devel
mailing list