Merge tag 'for-linus-20180629' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Small set of fixes for this series. Mostly just minor fixes, the only
  oddball in here is the sg change.

  The sg change came out of the stall fix for NVMe, where we added a
  mempool and limited us to a single page allocation. CONFIG_SG_DEBUG
  sort-of ruins that, since we'd need to account for that. That's
  actually a generic problem, since lots of drivers need to allocate SG
  lists. So this just removes support for CONFIG_SG_DEBUG, which I added
  back in 2007 and to my knowledge it was never useful.

  Anyway, outside of that, this pull contains:

   - clone of request with special payload fix (Bart)

   - drbd discard handling fix (Bart)

   - SATA blk-mq stall fix (me)

   - chunk size fix (Keith)

   - double free nvme rdma fix (Sagi)"

* tag 'for-linus-20180629' of git://git.kernel.dk/linux-block:
  sg: remove ->sg_magic member
  drbd: Fix drbd_request_prepare() discard handling
  blk-mq: don't queue more if we get a busy return
  block: Fix cloning of requests with a special payload
  nvme-rdma: fix possible double free of controller async event buffer
  block: Fix transfer when chunk sectors exceeds max

2 files changed, 16 insertions, 0 deletions

diff --git a/block/blk-core.c b/block/blk-core.c
index afd2596..f84a9b7 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -3473,6 +3473,10 @@ static void __blk_rq_prep_clone(struct request *dst, struct request *src)
 	dst->cpu = src->cpu;
 	dst->__sector = blk_rq_pos(src);
 	dst->__data_len = blk_rq_bytes(src);
+	if (src->rq_flags & RQF_SPECIAL_PAYLOAD) {
+		dst->rq_flags |= RQF_SPECIAL_PAYLOAD;
+		dst->special_vec = src->special_vec;
+	}
 	dst->nr_phys_segments = src->nr_phys_segments;
 	dst->ioprio = src->ioprio;
 	dst->extra_len = src->extra_len;
diff --git a/block/blk-mq.c b/block/blk-mq.c
index b429d51..9591926 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1075,6 +1075,9 @@ static bool blk_mq_mark_tag_wait(struct blk_mq_hw_ctx **hctx,
 
 #define BLK_MQ_RESOURCE_DELAY	3		/* ms units */
 
+/*
+ * Returns true if we did some work AND can potentially do more.
+ */
 bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
 			     bool got_budget)
 {
@@ -1205,8 +1208,17 @@ bool blk_mq_dispatch_rq_list(struct request_queue *q, struct list_head *list,
 			blk_mq_run_hw_queue(hctx, true);
 		else if (needs_restart && (ret == BLK_STS_RESOURCE))
 			blk_mq_delay_run_hw_queue(hctx, BLK_MQ_RESOURCE_DELAY);
+
+		return false;
 	}
 
+	/*
+	 * If the host/device is unable to accept more work, inform the
+	 * caller of that.
+	 */
+	if (ret == BLK_STS_RESOURCE || ret == BLK_STS_DEV_RESOURCE)
+		return false;
+
 	return (queued + errors) != 0;
 }