scsi: ibmvfc: Add size parameter to ibmvfc_init_event_pool()

With the upcoming addition of Sub-CRQs the event pool size may vary
per-queue.

Add a size parameter to ibmvfc_init_event_pool() such that different size
event pools can be requested by ibmvfc_alloc_queue().

Link: https://lore.kernel.org/r/20210114203148.246656-5-tyreld@linux.ibm.com
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/ibmvscsi/ibmvfc.c

@@ -723,19 +723,23 @@ static int ibmvfc_send_crq_init_complete(struct ibmvfc_host *vhost)
  * Returns zero on success.
  **/
 static int ibmvfc_init_event_pool(struct ibmvfc_host *vhost,
-				  struct ibmvfc_queue *queue)
+				  struct ibmvfc_queue *queue,
+				  unsigned int size)
 {
 	int i;
 	struct ibmvfc_event_pool *pool = &queue->evt_pool;
 
 	ENTER;
-	pool->size = max_requests + IBMVFC_NUM_INTERNAL_REQ;
-	pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
+	if (!size)
+		return 0;
+
+	pool->size = size;
+	pool->events = kcalloc(size, sizeof(*pool->events), GFP_KERNEL);
 	if (!pool->events)
 		return -ENOMEM;
 
 	pool->iu_storage = dma_alloc_coherent(vhost->dev,
-					      pool->size * sizeof(*pool->iu_storage),
+					      size * sizeof(*pool->iu_storage),
 					      &pool->iu_token, 0);
 
 	if (!pool->iu_storage) {
@@ -747,7 +751,7 @@ static int ibmvfc_init_event_pool(struct ibmvfc_host *vhost,
 	INIT_LIST_HEAD(&queue->free);
 	spin_lock_init(&queue->l_lock);
 
-	for (i = 0; i < pool->size; ++i) {
+	for (i = 0; i < size; ++i) {
 		struct ibmvfc_event *evt = &pool->events[i];
 
 		atomic_set(&evt->free, 1);
@@ -5013,6 +5017,7 @@ static int ibmvfc_alloc_queue(struct ibmvfc_host *vhost,
 {
 	struct device *dev = vhost->dev;
 	size_t fmt_size;
+	unsigned int pool_size = 0;
 
 	ENTER;
 	spin_lock_init(&queue->_lock);
@@ -5021,10 +5026,7 @@ static int ibmvfc_alloc_queue(struct ibmvfc_host *vhost,
 	switch (fmt) {
 	case IBMVFC_CRQ_FMT:
 		fmt_size = sizeof(*queue->msgs.crq);
-		if (ibmvfc_init_event_pool(vhost, queue)) {
-			dev_err(dev, "Couldn't initialize event pool.\n");
-			return -ENOMEM;
-		}
+		pool_size = max_requests + IBMVFC_NUM_INTERNAL_REQ;
 		break;
 	case IBMVFC_ASYNC_FMT:
 		fmt_size = sizeof(*queue->msgs.async);
@@ -5034,6 +5036,11 @@ static int ibmvfc_alloc_queue(struct ibmvfc_host *vhost,
 		return -EINVAL;
 	}
 
+	if (ibmvfc_init_event_pool(vhost, queue, pool_size)) {
+		dev_err(dev, "Couldn't initialize event pool.\n");
+		return -ENOMEM;
+	}
+
 	queue->msgs.handle = (void *)get_zeroed_page(GFP_KERNEL);
 	if (!queue->msgs.handle)
 		return -ENOMEM;