netfilter: remove IPvX specific parts from nf_conntrack_l4proto.h

[pandora-kernel.git] / block / blk-barrier.c

diff --git a/block/blk-barrier.c b/block/blk-barrier.c
index b03d880..f7dae57 100644 (file)
--- a/block/blk-barrier.c
+++ b/block/blk-barrier.c
@@ -162,6 +162,26 @@ static inline bool start_ordered(struct request_queue *q, struct request **rqp)
        q->ordered = q->next_ordered;
        q->ordseq |= QUEUE_ORDSEQ_STARTED;
 
+       /*
+        * For an empty barrier, there's no actual BAR request, which
+        * in turn makes POSTFLUSH unnecessary.  Mask them off.
+        */
+       if (!rq->hard_nr_sectors) {
+               q->ordered &= ~(QUEUE_ORDERED_DO_BAR |
+                               QUEUE_ORDERED_DO_POSTFLUSH);
+               /*
+                * Empty barrier on a write-through device w/ ordered
+                * tag has no command to issue and without any command
+                * to issue, ordering by tag can't be used.  Drain
+                * instead.
+                */
+               if ((q->ordered & QUEUE_ORDERED_BY_TAG) &&
+                   !(q->ordered & QUEUE_ORDERED_DO_PREFLUSH)) {
+                       q->ordered &= ~QUEUE_ORDERED_BY_TAG;
+                       q->ordered |= QUEUE_ORDERED_BY_DRAIN;
+               }
+       }
+
        /* stash away the original request */
        elv_dequeue_request(q, rq);
        q->orig_bar_rq = rq;
@@ -171,13 +191,9 @@ static inline bool start_ordered(struct request_queue *q, struct request **rqp)
         * Queue ordered sequence.  As we stack them at the head, we
         * need to queue in reverse order.  Note that we rely on that
         * no fs request uses ELEVATOR_INSERT_FRONT and thus no fs
-        * request gets inbetween ordered sequence. If this request is
-        * an empty barrier, we don't need to do a postflush ever since
-        * there will be no data written between the pre and post flush.
-        * Hence a single flush will suffice.
+        * request gets inbetween ordered sequence.
         */
-       if ((q->ordered & QUEUE_ORDERED_DO_POSTFLUSH) &&
-           !blk_empty_barrier(q->orig_bar_rq)) {
+       if (q->ordered & QUEUE_ORDERED_DO_POSTFLUSH) {
                queue_flush(q, QUEUE_ORDERED_DO_POSTFLUSH);
                rq = &q->post_flush_rq;
        } else
@@ -286,7 +302,7 @@ static void bio_end_empty_barrier(struct bio *bio, int err)
  * Description:
  *    Issue a flush for the block device in question. Caller can supply
  *    room for storing the error offset in case of a flush error, if they
- *    wish to.  Caller must run wait_for_completion() on its own.
+ *    wish to.
  */
 int blkdev_issue_flush(struct block_device *bdev, sector_t *error_sector)
 {