Merge tag 'for-linus-20180204' of git://git.kernel.dk/linux-block

Pull more block updates from Jens Axboe:
 "Most of this is fixes and not new code/features:

   - skd fix from Arnd, fixing a build error dependent on sla allocator
     type.

   - blk-mq scheduler discard merging fixes, one from me and one from
     Keith. This fixes a segment miscalculation for blk-mq-sched, where
     we mistakenly think two segments are physically contigious even
     though the request isn't carrying real data. Also fixes a bio-to-rq
     merge case.

   - Don't re-set a bit on the buffer_head flags, if it's already set.
     This can cause scalability concerns on bigger machines and
     workloads. From Kemi Wang.

   - Add BLK_STS_DEV_RESOURCE return value to blk-mq, allowing us to
     distuingish between a local (device related) resource starvation
     and a global one. The latter might happen without IO being in
     flight, so it has to be handled a bit differently. From Ming"

* tag 'for-linus-20180204' of git://git.kernel.dk/linux-block:
  block: skd: fix incorrect linux/slab_def.h inclusion
  buffer: Avoid setting buffer bits that are already set
  blk-mq-sched: Enable merging discard bio into request
  blk-mq: fix discard merge with scheduler attached
  blk-mq: introduce BLK_STS_DEV_RESOURCE

4 files changed, 7 insertions, 6 deletions

diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 6655893a3a7a..287a09611c0f 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -1230,7 +1230,7 @@ static blk_status_t null_handle_cmd(struct nullb_cmd *cmd)
 				return BLK_STS_OK;
 			} else
 				/* requeue request */
-				return BLK_STS_RESOURCE;
+				return BLK_STS_DEV_RESOURCE;
 		}
 	}
 
diff --git a/drivers/block/skd_main.c b/drivers/block/skd_main.c
index de0d08133c7e..e41935ab41ef 100644
--- a/drivers/block/skd_main.c
+++ b/drivers/block/skd_main.c
@@ -32,7 +32,6 @@
 #include <linux/aer.h>
 #include <linux/wait.h>
 #include <linux/stringify.h>
-#include <linux/slab_def.h>
 #include <scsi/scsi.h>
 #include <scsi/sg.h>
 #include <linux/io.h>
@@ -2603,7 +2602,8 @@ static void *skd_alloc_dma(struct skd_device *skdev, struct kmem_cache *s,
 	buf = kmem_cache_alloc(s, gfp);
 	if (!buf)
 		return NULL;
-	*dma_handle = dma_map_single(dev, buf, s->size, dir);
+	*dma_handle = dma_map_single(dev, buf,
+				     kmem_cache_size(s), dir);
 	if (dma_mapping_error(dev, *dma_handle)) {
 		kmem_cache_free(s, buf);
 		buf = NULL;
@@ -2618,7 +2618,8 @@ static void skd_free_dma(struct skd_device *skdev, struct kmem_cache *s,
 	if (!vaddr)
 		return;
 
-	dma_unmap_single(&skdev->pdev->dev, dma_handle, s->size, dir);
+	dma_unmap_single(&skdev->pdev->dev, dma_handle,
+			 kmem_cache_size(s), dir);
 	kmem_cache_free(s, vaddr);
 }
 
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 68846897d213..79908e6ddbf2 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -276,7 +276,7 @@ static blk_status_t virtio_queue_rq(struct blk_mq_hw_ctx *hctx,
 		/* Out of mem doesn't actually happen, since we fall back
 		 * to direct descriptors */
 		if (err == -ENOMEM || err == -ENOSPC)
-			return BLK_STS_RESOURCE;
+			return BLK_STS_DEV_RESOURCE;
 		return BLK_STS_IOERR;
 	}
 
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 891265acb10e..e126e4cac2ca 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -911,7 +911,7 @@ out_err:
 out_busy:
 	blk_mq_stop_hw_queue(hctx);
 	spin_unlock_irqrestore(&rinfo->ring_lock, flags);
-	return BLK_STS_RESOURCE;
+	return BLK_STS_DEV_RESOURCE;
 }
 
 static void blkif_complete_rq(struct request *rq)