block: silently error an unsupported barrier bio

This fixes a "regression" from 2.6.28, where the barrier probes that file
systems may do would trigger additional end request warnings in dmesg.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

diff --git a/block/blk-core.c b/block/blk-core.c
index 9e2e86f..ae75c04 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1451,6 +1451,11 @@ static inline void __generic_make_request(struct bio *bio)
                        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);