| Message ID | 1255343266-9476-2-git-send-email-apw@canonical.com |
|---|---|
| State | Accepted |
| Commit | eabcb5a2bedd09fae7f49c799b2148382234c2e9 |
| Headers | show |
Returning -EOPNOTSUPP makes sense for queues that do not support barriers regardless of the bio containing data or not. ACK
Should get used to that now... Andy Whitcroft wrote: > BugLink: http://bugs.launchpad.net/bugs/420423 > Patch: http://patchwork.kernel.org/patch/39589/ > > With 2.6.31-rc5 in a KVM guest using dm and virtio_blk, we see the > following errors: > > end_request: I/O error, dev vda, sector 0 > end_request: I/O error, dev vda, sector 0 > > The errors go away if dm stops submitting empty barriers, by reverting: > > commit 52b1fd5a27c625c78373e024bf570af3c9d44a79 > Author: Mikulas Patocka <mpatocka@redhat.com> > dm: send empty barriers to targets in dm_flush > > We should error all barriers, even empty barriers, on devices like > virtio_blk which don't support them. > > See also: > > https://bugzilla.redhat.com/514901 > > Signed-off-by: Mark McLoughlin <markmc@redhat.com> > Cc: Rusty Russell <rusty@rustcorp.com.au> > Cc: Mikulas Patocka <mpatocka@redhat.com> > Cc: Alasdair G Kergon <agk@redhat.com> > Cc: Neil Brown <neilb@suse.de> > Signed-off-by: Andy Whitcroft <apw@canonical.com> Acked-by: Stefan Bader <stefan.bader@canonical.com> > --- > block/blk-core.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/block/blk-core.c b/block/blk-core.c > index e3299a7..af20cbd 100644 > --- a/block/blk-core.c > +++ b/block/blk-core.c > @@ -1163,7 +1163,7 @@ static int __make_request(struct request_queue *q, struct bio *bio) > const int unplug = bio_unplug(bio); > int rw_flags; > > - if (bio_barrier(bio) && bio_has_data(bio) && > + if (bio_barrier(bio) && > (q->next_ordered == QUEUE_ORDERED_NONE)) { > bio_endio(bio, -EOPNOTSUPP); > return 0;
diff --git a/block/blk-core.c b/block/blk-core.c index e3299a7..af20cbd 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1163,7 +1163,7 @@ static int __make_request(struct request_queue *q, struct bio *bio) const int unplug = bio_unplug(bio); int rw_flags; - if (bio_barrier(bio) && bio_has_data(bio) && + if (bio_barrier(bio) && (q->next_ordered == QUEUE_ORDERED_NONE)) { bio_endio(bio, -EOPNOTSUPP); return 0;
BugLink: http://bugs.launchpad.net/bugs/420423 Patch: http://patchwork.kernel.org/patch/39589/ With 2.6.31-rc5 in a KVM guest using dm and virtio_blk, we see the following errors: end_request: I/O error, dev vda, sector 0 end_request: I/O error, dev vda, sector 0 The errors go away if dm stops submitting empty barriers, by reverting: commit 52b1fd5a27c625c78373e024bf570af3c9d44a79 Author: Mikulas Patocka <mpatocka@redhat.com> dm: send empty barriers to targets in dm_flush We should error all barriers, even empty barriers, on devices like virtio_blk which don't support them. See also: https://bugzilla.redhat.com/514901 Signed-off-by: Mark McLoughlin <markmc@redhat.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Mikulas Patocka <mpatocka@redhat.com> Cc: Alasdair G Kergon <agk@redhat.com> Cc: Neil Brown <neilb@suse.de> Signed-off-by: Andy Whitcroft <apw@canonical.com> --- block/blk-core.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)