block: remove REQ_HARDBARRIER
REQ_HARDBARRIER is dead now, so remove the leftovers. What's left
at this point is:
- various checks inside the block layer.
- sanity checks in bio based drivers.
- now unused bio_empty_barrier helper.
- Xen blockfront use of BLKIF_OP_WRITE_BARRIER - it's dead for a while,
but Xen really needs to sort out it's barrier situaton.
- setting of ordered tags in uas - dead code copied from old scsi
drivers.
- scsi different retry for barriers - it's dead and should have been
removed when flushes were converted to FS requests.
- blktrace handling of barriers - removed. Someone who knows blktrace
better should add support for REQ_FLUSH and REQ_FUA, though.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
diff --git a/block/elevator.c b/block/elevator.c
index 282e830..2569512 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -429,7 +429,7 @@
q->nr_sorted--;
boundary = q->end_sector;
- stop_flags = REQ_SOFTBARRIER | REQ_HARDBARRIER | REQ_STARTED;
+ stop_flags = REQ_SOFTBARRIER | REQ_STARTED;
list_for_each_prev(entry, &q->queue_head) {
struct request *pos = list_entry_rq(entry);
@@ -691,7 +691,7 @@
void __elv_add_request(struct request_queue *q, struct request *rq, int where,
int plug)
{
- if (rq->cmd_flags & (REQ_SOFTBARRIER | REQ_HARDBARRIER)) {
+ if (rq->cmd_flags & REQ_SOFTBARRIER) {
/* barriers are scheduling boundary, update end_sector */
if (rq->cmd_type == REQ_TYPE_FS ||
(rq->cmd_flags & REQ_DISCARD)) {