scsi: ibmvfc: Init/free event pool during queue allocation/free

The event pool and CRQ used to be separate entities of the adapter host
structure and as such were allocated and freed independently of each
other. Recent work as defined a generic queue structure with an event pool
specific to each queue. As such the event pool for each queue shouldn't be
allocated/freed independently, but instead performed as part of the queue
allocation/free routines.

Move the calls to ibmvfc_event_pool_{init|free} into
ibmvfc_{alloc|free}_queue respectively. The only functional change here is
that the CRQ cannot be released in ibmvfc_remove until after the event pool
has been successfully purged since releasing the queue will also free the
event pool.

Link: https://lore.kernel.org/r/20210114203148.246656-4-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

@@ -807,6 +807,8 @@ static void ibmvfc_free_queue(struct ibmvfc_host *vhost,
 	dma_unmap_single(dev, queue->msg_token, PAGE_SIZE, DMA_BIDIRECTIONAL);
 	free_page((unsigned long)queue->msgs.handle);
 	queue->msgs.handle = NULL;
+
+	ibmvfc_free_event_pool(vhost, queue);
 }
 
 /**
@@ -5019,6 +5021,10 @@ 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;
+		}
 		break;
 	case IBMVFC_ASYNC_FMT:
 		fmt_size = sizeof(*queue->msgs.async);
@@ -5333,13 +5339,8 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 		goto kill_kthread;
 	}
 
-	if ((rc = ibmvfc_init_event_pool(vhost, &vhost->crq))) {
-		dev_err(dev, "Couldn't initialize event pool. rc=%d\n", rc);
-		goto release_crq;
-	}
-
 	if ((rc = scsi_add_host(shost, dev)))
-		goto release_event_pool;
+		goto release_crq;
 
 	fc_host_dev_loss_tmo(shost) = IBMVFC_DEV_LOSS_TMO;
 
@@ -5362,8 +5363,6 @@ static int ibmvfc_probe(struct vio_dev *vdev, const struct vio_device_id *id)
 
 remove_shost:
 	scsi_remove_host(shost);
-release_event_pool:
-	ibmvfc_free_event_pool(vhost, &vhost->crq);
 release_crq:
 	ibmvfc_release_crq_queue(vhost);
 kill_kthread:
@@ -5398,7 +5397,6 @@ static int ibmvfc_remove(struct vio_dev *vdev)
 	spin_unlock_irqrestore(vhost->host->host_lock, flags);
 
 	ibmvfc_wait_while_resetting(vhost);
-	ibmvfc_release_crq_queue(vhost);
 	kthread_stop(vhost->work_thread);
 	fc_remove_host(vhost->host);
 	scsi_remove_host(vhost->host);
@@ -5408,7 +5406,7 @@ static int ibmvfc_remove(struct vio_dev *vdev)
 	list_splice_init(&vhost->purge, &purge);
 	spin_unlock_irqrestore(vhost->host->host_lock, flags);
 	ibmvfc_complete_purge(&purge);
-	ibmvfc_free_event_pool(vhost, &vhost->crq);
+	ibmvfc_release_crq_queue(vhost);
 
 	ibmvfc_free_mem(vhost);
 	spin_lock(&ibmvfc_driver_lock);