blk-mq: remove alloc_hctx and free_hctx methods

There is no need for drivers to control hardware context allocation
now that we do the context to node mapping in common code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>

4 files changed, 6 insertions, 60 deletions

diff --git a/block/blk-mq.c b/block/blk-mq.c
index 5cc4b871cb11..f27fe44230c2 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -1335,21 +1335,6 @@ struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, const int cpu)
 }
 EXPORT_SYMBOL(blk_mq_map_queue);
 
-struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *set,
-                                                   unsigned int hctx_index,
-                                                   int node)
-{
-        return kzalloc_node(sizeof(struct blk_mq_hw_ctx), GFP_KERNEL, node);
-}
-EXPORT_SYMBOL(blk_mq_alloc_single_hw_queue);
-
-void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *hctx,
-                                 unsigned int hctx_index)
-{
-        kfree(hctx);
-}
-EXPORT_SYMBOL(blk_mq_free_single_hw_queue);
-
 static void blk_mq_free_rq_map(struct blk_mq_tag_set *set,
                 struct blk_mq_tags *tags, unsigned int hctx_idx)
 {
@@ -1590,7 +1575,7 @@ static void blk_mq_free_hw_queues(struct request_queue *q,
 
         queue_for_each_hw_ctx(q, hctx, i) {
                 free_cpumask_var(hctx->cpumask);
-                set->ops->free_hctx(hctx, i);
+                kfree(hctx);
         }
 }
 
@@ -1811,7 +1796,8 @@ struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *set)
         for (i = 0; i < set->nr_hw_queues; i++) {
                 int node = blk_mq_hw_queue_to_node(map, i);
 
-                hctxs[i] = set->ops->alloc_hctx(set, i, node);
+                hctxs[i] = kzalloc_node(sizeof(struct blk_mq_hw_ctx),
+                                        GFP_KERNEL, node);
                 if (!hctxs[i])
                         goto err_hctxs;
 
@@ -1898,7 +1884,7 @@ err_hctxs:
                 if (!hctxs[i])
                         break;
                 free_cpumask_var(hctxs[i]->cpumask);
-                set->ops->free_hctx(hctxs[i], i);
+                kfree(hctxs[i]);
         }
 err_map:
         kfree(hctxs);
@@ -1983,9 +1969,7 @@ int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set)
         if (set->queue_depth < set->reserved_tags + BLK_MQ_TAG_MIN)
                 return -EINVAL;
 
-        if (!set->nr_hw_queues ||
-            !set->ops->queue_rq || !set->ops->map_queue ||
-            !set->ops->alloc_hctx || !set->ops->free_hctx)
+        if (!set->nr_hw_queues || !set->ops->queue_rq || !set->ops->map_queue)
                 return -EINVAL;
 
 
diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 4d33c8c25fbf..b40af63a5476 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -321,18 +321,6 @@ static int null_queue_rq(struct blk_mq_hw_ctx *hctx, struct request *rq)
         return BLK_MQ_RQ_QUEUE_OK;
 }
 
-static struct blk_mq_hw_ctx *null_alloc_hctx(struct blk_mq_tag_set *set,
-                                             unsigned int hctx_index,
-                                             int node)
-{
-        return kzalloc_node(sizeof(struct blk_mq_hw_ctx), GFP_KERNEL, node);
-}
-
-static void null_free_hctx(struct blk_mq_hw_ctx *hctx, unsigned int hctx_index)
-{
-        kfree(hctx);
-}
-
 static void null_init_queue(struct nullb *nullb, struct nullb_queue *nq)
 {
         BUG_ON(!nullb);
@@ -360,17 +348,6 @@ static struct blk_mq_ops null_mq_ops = {
         .map_queue      = blk_mq_map_queue,
         .init_hctx      = null_init_hctx,
         .complete       = null_softirq_done_fn,
-        .alloc_hctx     = blk_mq_alloc_single_hw_queue,
-        .free_hctx      = blk_mq_free_single_hw_queue,
-};
-
-static struct blk_mq_ops null_mq_ops_pernode = {
-        .queue_rq       = null_queue_rq,
-        .map_queue      = blk_mq_map_queue,
-        .init_hctx      = null_init_hctx,
-        .complete       = null_softirq_done_fn,
-        .alloc_hctx     = null_alloc_hctx,
-        .free_hctx      = null_free_hctx,
 };
 
 static void null_del_dev(struct nullb *nullb)
@@ -496,10 +473,7 @@ static int null_add_dev(void)
                 goto out_free_nullb;
 
         if (queue_mode == NULL_Q_MQ) {
-                if (use_per_node_hctx)
-                        nullb->tag_set.ops = &null_mq_ops_pernode;
-                else
-                        nullb->tag_set.ops = &null_mq_ops;
+                nullb->tag_set.ops = &null_mq_ops;
                 nullb->tag_set.nr_hw_queues = submit_queues;
                 nullb->tag_set.queue_depth = hw_queue_depth;
                 nullb->tag_set.numa_node = home_node;
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 7a51f065edcd..16c21c0cb14d 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -497,8 +497,6 @@ static int virtblk_init_request(void *data, struct request *rq,
 static struct blk_mq_ops virtio_mq_ops = {
         .queue_rq       = virtio_queue_rq,
         .map_queue      = blk_mq_map_queue,
-        .alloc_hctx     = blk_mq_alloc_single_hw_queue,
-        .free_hctx      = blk_mq_free_single_hw_queue,
         .complete       = virtblk_request_done,
         .init_request   = virtblk_init_request,
 };
diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index 2bd82f399128..91dfb75ce39f 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -79,9 +79,6 @@ struct blk_mq_tag_set {
 
 typedef int (queue_rq_fn)(struct blk_mq_hw_ctx *, struct request *);
 typedef struct blk_mq_hw_ctx *(map_queue_fn)(struct request_queue *, const int);
-typedef struct blk_mq_hw_ctx *(alloc_hctx_fn)(struct blk_mq_tag_set *,
-                unsigned int, int);
-typedef void (free_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
 typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int);
 typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int);
 typedef int (init_request_fn)(void *, struct request *, unsigned int,
@@ -108,12 +105,6 @@ struct blk_mq_ops {
         softirq_done_fn         *complete;
 
         /*
-         * Override for hctx allocations (should probably go)
-         */
-        alloc_hctx_fn           *alloc_hctx;
-        free_hctx_fn            *free_hctx;
-
-        /*
          * Called when the block layer side of a hardware queue has been
          * set up, allowing the driver to allocate/init matching structures.
          * Ditto for exit/teardown.
@@ -166,7 +157,6 @@ struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag);
 
 struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index);
 struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_tag_set *, unsigned int, int);
-void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *, unsigned int);
 
 void blk_mq_end_io(struct request *rq, int error);
 void __blk_mq_end_io(struct request *rq, int error);