blocK: Restore barrier support for md and probably other virtual devices.
The next_ordered flag is only meaningful for devices that use __make_request.
So move the test against next_ordered out of generic code and in to
__make_request
Since this test was added, barriers have not worked on md or any
devices that don't use __make_request and so don't bother to set
next_ordered. (dm explicitly sets something other than
QUEUE_ORDERED_NONE since
commit 99360b4c18f7675b50d283301d46d755affe75fd
but notes in the comments that it is otherwise meaningless).
Cc: Ken Milmore <ken.milmore@googlemail.com>
Cc: stable@kernel.org
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/block/blk-core.c b/block/blk-core.c
index 02b8713..4b45435 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1170,6 +1170,11 @@
const int unplug = bio_unplug(bio);
int rw_flags;
+ if (bio_barrier(bio) && bio_has_data(bio) &&
+ (q->next_ordered == QUEUE_ORDERED_NONE)) {
+ bio_endio(bio, -EOPNOTSUPP);
+ return 0;
+ }
/*
* low level driver can indicate that it wants pages above a
* certain limit bounced to low memory (ie for highmem, or even
@@ -1470,11 +1475,6 @@
err = -EOPNOTSUPP;
goto end_io;
}
- if (bio_barrier(bio) && bio_has_data(bio) &&
- (q->next_ordered == QUEUE_ORDERED_NONE)) {
- err = -EOPNOTSUPP;
- goto end_io;
- }
ret = q->make_request_fn(q, bio);
} while (ret);
