block: simplify queue allocation

Current make_request based drivers use either blk_alloc_queue_node or
blk_alloc_queue to allocate a queue, and then set up the make_request_fn
function pointer and a few parameters using the blk_queue_make_request
helper.  Simplify this by passing the make_request pointer to
blk_alloc_queue, and while at it merge the _node variant into the main
helper by always passing a node_id, and remove the superfluous gfp_mask
parameter.  A lower-level __blk_alloc_queue is kept for the blk-mq case.

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

5 files changed, 28 insertions, 59 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index a229b94d5390..c15a26096038 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -1010,7 +1010,7 @@ unlock:
  * blkcg_init_queue - initialize blkcg part of request queue
  * @q: request_queue to initialize
  *
- * Called from blk_alloc_queue_node(). Responsible for initializing blkcg
+ * Called from __blk_alloc_queue(). Responsible for initializing blkcg
  * part of new request_queue @q.
  *
  * RETURNS:
diff --git a/block/blk-core.c b/block/blk-core.c
index eaf6cb3887e6..18b8c09d093e 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -388,12 +388,6 @@ void blk_cleanup_queue(struct request_queue *q)
 }
 EXPORT_SYMBOL(blk_cleanup_queue);
 
-struct request_queue *blk_alloc_queue(gfp_t gfp_mask)
-{
-	return blk_alloc_queue_node(gfp_mask, NUMA_NO_NODE);
-}
-EXPORT_SYMBOL(blk_alloc_queue);
-
 /**
  * blk_queue_enter() - try to increase q->q_usage_counter
  * @q: request queue pointer
@@ -470,24 +464,19 @@ static void blk_timeout_work(struct work_struct *work)
 {
 }
 
-/**
- * blk_alloc_queue_node - allocate a request queue
- * @gfp_mask: memory allocation flags
- * @node_id: NUMA node to allocate memory from
- */
-struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
+struct request_queue *__blk_alloc_queue(int node_id)
 {
 	struct request_queue *q;
 	int ret;
 
 	q = kmem_cache_alloc_node(blk_requestq_cachep,
-				gfp_mask | __GFP_ZERO, node_id);
+				GFP_KERNEL | __GFP_ZERO, node_id);
 	if (!q)
 		return NULL;
 
 	q->last_merge = NULL;
 
-	q->id = ida_simple_get(&blk_queue_ida, 0, 0, gfp_mask);
+	q->id = ida_simple_get(&blk_queue_ida, 0, 0, GFP_KERNEL);
 	if (q->id < 0)
 		goto fail_q;
 
@@ -495,7 +484,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 	if (ret)
 		goto fail_id;
 
-	q->backing_dev_info = bdi_alloc_node(gfp_mask, node_id);
+	q->backing_dev_info = bdi_alloc_node(GFP_KERNEL, node_id);
 	if (!q->backing_dev_info)
 		goto fail_split;
 
@@ -541,6 +530,9 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
 	if (blkcg_init_queue(q))
 		goto fail_ref;
 
+	blk_queue_dma_alignment(q, 511);
+	blk_set_default_limits(&q->limits);
+
 	return q;
 
 fail_ref:
@@ -557,7 +549,22 @@ fail_q:
 	kmem_cache_free(blk_requestq_cachep, q);
 	return NULL;
 }
-EXPORT_SYMBOL(blk_alloc_queue_node);
+
+struct request_queue *blk_alloc_queue(make_request_fn make_request, int node_id)
+{
+	struct request_queue *q;
+
+	if (WARN_ON_ONCE(!make_request))
+		return -EINVAL;
+
+	q = __blk_alloc_queue(node_id);
+	if (!q)
+		return NULL;
+	q->make_request_fn = make_request;
+	q->nr_requests = BLKDEV_MAX_RQ;
+	return q;
+}
+EXPORT_SYMBOL(blk_alloc_queue);
 
 bool blk_get_queue(struct request_queue *q)
 {
diff --git a/block/blk-mq.c b/block/blk-mq.c
index 216bf62e88b6..f6291ceedee4 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2729,7 +2729,7 @@ struct request_queue *blk_mq_init_queue_data(struct blk_mq_tag_set *set,
 {
 	struct request_queue *uninit_q, *q;
 
-	uninit_q = blk_alloc_queue_node(GFP_KERNEL, set->numa_node);
+	uninit_q = __blk_alloc_queue(set->numa_node);
 	if (!uninit_q)
 		return ERR_PTR(-ENOMEM);
 	uninit_q->queuedata = queuedata;
@@ -2939,11 +2939,7 @@ struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set,
 	INIT_LIST_HEAD(&q->requeue_list);
 	spin_lock_init(&q->requeue_lock);
 
-	blk_queue_make_request(q, blk_mq_make_request);
-
-	/*
-	 * Do this after blk_queue_make_request() overrides it...
-	 */
+	q->make_request_fn = blk_mq_make_request;
 	q->nr_requests = set->queue_depth;
 
 	/*
diff --git a/block/blk-settings.c b/block/blk-settings.c
index c8eda2e7b91e..126d216a2db6 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -87,42 +87,6 @@ void blk_set_stacking_limits(struct queue_limits *lim)
 EXPORT_SYMBOL(blk_set_stacking_limits);
 
 /**
- * blk_queue_make_request - define an alternate make_request function for a device
- * @q:  the request queue for the device to be affected
- * @mfn: the alternate make_request function
- *
- * Description:
- *    The normal way for &struct bios to be passed to a device
- *    driver is for them to be collected into requests on a request
- *    queue, and then to allow the device driver to select requests
- *    off that queue when it is ready.  This works well for many block
- *    devices. However some block devices (typically virtual devices
- *    such as md or lvm) do not benefit from the processing on the
- *    request queue, and are served best by having the requests passed
- *    directly to them.  This can be achieved by providing a function
- *    to blk_queue_make_request().
- *
- * Caveat:
- *    The driver that does this *must* be able to deal appropriately
- *    with buffers in "highmemory". This can be accomplished by either calling
- *    kmap_atomic() to get a temporary kernel mapping, or by calling
- *    blk_queue_bounce() to create a buffer in normal memory.
- **/
-void blk_queue_make_request(struct request_queue *q, make_request_fn *mfn)
-{
-	/*
-	 * set defaults
-	 */
-	q->nr_requests = BLKDEV_MAX_RQ;
-
-	q->make_request_fn = mfn;
-	blk_queue_dma_alignment(q, 511);
-
-	blk_set_default_limits(&q->limits);
-}
-EXPORT_SYMBOL(blk_queue_make_request);
-
-/**
  * blk_queue_bounce_limit - set bounce buffer limit for queue
  * @q: the request queue for the device
  * @max_addr: the maximum address the device can handle
diff --git a/block/blk.h b/block/blk.h
index d9673164a145..491e52fc0aa6 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -482,4 +482,6 @@ static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
 #endif
 }
 
+struct request_queue *__blk_alloc_queue(int node_id);
+
 #endif /* BLK_INTERNAL_H */