Merge tag 'for-linus-20190608' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:

 - Allow symlink from the bfq.weight cgroup parameter to the general
   weight (Angelo)

 - Damien is new skd maintainer (Bart)

 - NVMe pull request from Sagi, with a few small fixes.

 - Ensure we set DMA segment size properly, dma-debug is now tripping on
   these (Christoph)

 - Remove useless debugfs_create() return check (Greg)

 - Remove redundant unlikely() check on IS_ERR() (Kefeng)

 - Fixup request freeing on exit (Ming)

* tag 'for-linus-20190608' of git://git.kernel.dk/linux-block:
  block, bfq: add weight symlink to the bfq.weight cgroup parameter
  cgroup: let a symlink too be created with a cftype file
  block: free sched's request pool in blk_cleanup_queue
  nvme-rdma: use dynamic dma mapping per command
  nvme: Fix u32 overflow in the number of namespace list calculation
  mmc: also set max_segment_size in the device
  mtip32xx: also set max_segment_size in the device
  rsxx: don't call dma_set_max_seg_size
  nvme-pci: don't limit DMA segement size
  block: Drop unlikely before IS_ERR(_OR_NULL)
  block: aoe: no need to check return value of debugfs_create functions
  nvmet: fix data_len to 0 for bdev-backed write_zeroes
  MAINTAINERS: Hand over skd maintainership
  nvme-tcp: fix queue mapping when queue count is limited
  nvme-rdma: fix queue mapping when queue count is limited

1 files changed, 27 insertions, 3 deletions

diff --git a/block/blk-mq-sched.c b/block/blk-mq-sched.c
index 74c6bb871f7e..500cb04901cc 100644
--- a/block/blk-mq-sched.c
+++ b/block/blk-mq-sched.c
@@ -475,14 +475,18 @@ static int blk_mq_sched_alloc_tags(struct request_queue *q,
 	return ret;
 }
 
+/* called in queue's release handler, tagset has gone away */
 static void blk_mq_sched_tags_teardown(struct request_queue *q)
 {
-	struct blk_mq_tag_set *set = q->tag_set;
 	struct blk_mq_hw_ctx *hctx;
 	int i;
 
-	queue_for_each_hw_ctx(q, hctx, i)
-		blk_mq_sched_free_tags(set, hctx, i);
+	queue_for_each_hw_ctx(q, hctx, i) {
+		if (hctx->sched_tags) {
+			blk_mq_free_rq_map(hctx->sched_tags);
+			hctx->sched_tags = NULL;
+		}
+	}
 }
 
 int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)
@@ -523,6 +527,7 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)
 			ret = e->ops.init_hctx(hctx, i);
 			if (ret) {
 				eq = q->elevator;
+				blk_mq_sched_free_requests(q);
 				blk_mq_exit_sched(q, eq);
 				kobject_put(&eq->kobj);
 				return ret;
@@ -534,11 +539,30 @@ int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e)
 	return 0;
 
 err:
+	blk_mq_sched_free_requests(q);
 	blk_mq_sched_tags_teardown(q);
 	q->elevator = NULL;
 	return ret;
 }
 
+/*
+ * called in either blk_queue_cleanup or elevator_switch, tagset
+ * is required for freeing requests
+ */
+void blk_mq_sched_free_requests(struct request_queue *q)
+{
+	struct blk_mq_hw_ctx *hctx;
+	int i;
+
+	lockdep_assert_held(&q->sysfs_lock);
+	WARN_ON(!q->elevator);
+
+	queue_for_each_hw_ctx(q, hctx, i) {
+		if (hctx->sched_tags)
+			blk_mq_free_rqs(q->tag_set, hctx->sched_tags, i);
+	}
+}
+
 void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e)
 {
 	struct blk_mq_hw_ctx *hctx;