[PATCH v3 15/18] ibmvfc: send Cancel MAD down each hw scsi channel

[Tyrel Datwyler <tyreld@linux.ibm.com>]

In general the client needs to send Cancel MADs and task management
commands down the same channel as the command(s) intended to cancel or
abort. The client assigns cancel keys per LUN and thus must send a
Cancel down each channel commands were submitted for that LUN. Further,
the client then must wait for those cancel completions prior to
submitting a LUN RESET or ABORT TASK SET.

Add a cancel event pointer and cancel rsp iu storage to the
ibmvfc_sub_queue struct such that the cancel routine can assign a cancel
event to each applicable queue. When in legacy CRQ mode we fake treating
it as a subqueue by using a subqueue struct allocated on the stack. Wait
for completion of each submitted cancel.

Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
 drivers/scsi/ibmvscsi/ibmvfc.c | 104 ++++++++++++++++++++++-----------
 drivers/scsi/ibmvscsi/ibmvfc.h |  38 ++++++------
 2 files changed, 90 insertions(+), 52 deletions(-)

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index ec3db5a6baf3..e353b9e88104 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -2339,67 +2339,103 @@ static int ibmvfc_cancel_all(struct scsi_device *sdev, int type)
 {
 	struct ibmvfc_host *vhost = shost_priv(sdev->host);
 	struct ibmvfc_event *evt, *found_evt;
-	union ibmvfc_iu rsp;
-	int rsp_rc = -EBUSY;
+	struct ibmvfc_sub_queue *scrqs;
+	struct ibmvfc_sub_queue legacy_crq;
+	int rsp_rc = 0;
 	unsigned long flags;
 	u16 status;
+	int cancel_cnt = 0;
+	int num_hwq;
+	int ret = 0;
+	int i;
 
 	ENTER;
 	spin_lock_irqsave(vhost->host->host_lock, flags);
-	found_evt = NULL;
-	list_for_each_entry(evt, &vhost->sent, queue) {
-		if (evt->cmnd && evt->cmnd->device == sdev) {
-			found_evt = evt;
+	if (vhost->using_channels && vhost->scsi_scrqs.active_queues) {
+		num_hwq = vhost->scsi_scrqs.active_queues;
+		scrqs = vhost->scsi_scrqs.scrqs;
+	} else {
+		/* Use ibmvfc_sub_queue on the stack to fake legacy CRQ as a subqueue */
+		num_hwq = 1;
+		scrqs = &legacy_crq;
+	}
+
+	for (i = 0; i < num_hwq; i++) {
+		scrqs[i].cancel_event = NULL;
+		found_evt = NULL;
+		list_for_each_entry(evt, &vhost->sent, queue) {
+			if (evt->cmnd && evt->cmnd->device == sdev && evt->hwq == i) {
+				found_evt = evt;
+				cancel_cnt++;
+				break;
+			}
+		}
+
+		if (!found_evt)
+			continue;
+
+		if (vhost->logged_in) {
+			scrqs[i].cancel_event = ibmvfc_init_tmf(vhost, sdev, type);
+			scrqs[i].cancel_event->hwq = i;
+			scrqs[i].cancel_event->sync_iu = &scrqs[i].cancel_rsp;
+			rsp_rc = ibmvfc_send_event(scrqs[i].cancel_event, vhost, default_timeout);
+			if (rsp_rc)
+				break;
+		} else {
+			rsp_rc = -EBUSY;
 			break;
 		}
 	}
 
-	if (!found_evt) {
+	spin_unlock_irqrestore(vhost->host->host_lock, flags);
+
+	if (!cancel_cnt) {
 		if (vhost->log_level > IBMVFC_DEFAULT_LOG_LEVEL)
 			sdev_printk(KERN_INFO, sdev, "No events found to cancel\n");
-		spin_unlock_irqrestore(vhost->host->host_lock, flags);
 		return 0;
 	}
 
-	if (vhost->logged_in) {
-		evt = ibmvfc_init_tmf(vhost, sdev, type);
-		evt->sync_iu = &rsp;
-		rsp_rc = ibmvfc_send_event(evt, vhost, default_timeout);
-	}
-
-	spin_unlock_irqrestore(vhost->host->host_lock, flags);
-
 	if (rsp_rc != 0) {
 		sdev_printk(KERN_ERR, sdev, "Failed to send cancel event. rc=%d\n", rsp_rc);
 		/* If failure is received, the host adapter is most likely going
 		 through reset, return success so the caller will wait for the command
 		 being cancelled to get returned */
-		return 0;
+		goto free_events;
 	}
 
 	sdev_printk(KERN_INFO, sdev, "Cancelling outstanding commands.\n");
 
-	wait_for_completion(&evt->comp);
-	status = be16_to_cpu(rsp.mad_common.status);
-	spin_lock_irqsave(vhost->host->host_lock, flags);
-	ibmvfc_free_event(evt);
-	spin_unlock_irqrestore(vhost->host->host_lock, flags);
+	for (i = 0; i < num_hwq; i++) {
+		if (!scrqs[i].cancel_event)
+			continue;
 
-	if (status != IBMVFC_MAD_SUCCESS) {
-		sdev_printk(KERN_WARNING, sdev, "Cancel failed with rc=%x\n", status);
-		switch (status) {
-		case IBMVFC_MAD_DRIVER_FAILED:
-		case IBMVFC_MAD_CRQ_ERROR:
-			/* Host adapter most likely going through reset, return success to
-			 the caller will wait for the command being cancelled to get returned */
-			return 0;
-		default:
-			return -EIO;
-		};
+		wait_for_completion(&scrqs[i].cancel_event->comp);
+		status = be16_to_cpu(scrqs[i].cancel_rsp.mad_common.status);
+
+		if (status != IBMVFC_MAD_SUCCESS) {
+			sdev_printk(KERN_WARNING, sdev, "Cancel failed with rc=%x\n", status);
+			switch (status) {
+			case IBMVFC_MAD_DRIVER_FAILED:
+			case IBMVFC_MAD_CRQ_ERROR:
+				/* Host adapter most likely going through reset, return success to
+				 the caller will wait for the command being cancelled to get returned */
+				goto free_events;
+			default:
+				ret = -EIO;
+				goto free_events;
+			};
+		}
 	}
 
 	sdev_printk(KERN_INFO, sdev, "Successfully cancelled outstanding commands\n");
-	return 0;
+free_events:
+	spin_lock_irqsave(vhost->host->host_lock, flags);
+	for (i = 0; i < num_hwq; i++)
+		if (scrqs[i].cancel_event)
+			ibmvfc_free_event(scrqs[i].cancel_event);
+	spin_unlock_irqrestore(vhost->host->host_lock, flags);
+
+	return ret;
 }
 
 /**
diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h
index e0ffb0416223..980eb9afe93a 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.h
+++ b/drivers/scsi/ibmvscsi/ibmvfc.h
@@ -584,6 +584,24 @@ struct ibmvfc_connection_info {
 	__be64 reserved[16];
 } __packed __aligned(8);
 
+union ibmvfc_iu {
+	struct ibmvfc_mad_common mad_common;
+	struct ibmvfc_npiv_login_mad npiv_login;
+	struct ibmvfc_npiv_logout_mad npiv_logout;
+	struct ibmvfc_discover_targets discover_targets;
+	struct ibmvfc_port_login plogi;
+	struct ibmvfc_process_login prli;
+	struct ibmvfc_move_login move_login;
+	struct ibmvfc_query_tgt query_tgt;
+	struct ibmvfc_implicit_logout implicit_logout;
+	struct ibmvfc_tmf tmf;
+	struct ibmvfc_cmd cmd;
+	struct ibmvfc_passthru_mad passthru;
+	struct ibmvfc_channel_enquiry channel_enquiry;
+	struct ibmvfc_channel_setup_mad channel_setup;
+	struct ibmvfc_connection_info connection_info;
+} __packed __aligned(8);
+
 struct ibmvfc_trace_start_entry {
 	u32 xfer_len;
 } __packed;
@@ -666,6 +684,8 @@ struct ibmvfc_sub_queue {
 	dma_addr_t msg_token;
 	int size, cur;
 	struct ibmvfc_host *vhost;
+	struct ibmvfc_event *cancel_event;
+	union ibmvfc_iu cancel_rsp;
 	unsigned long cookie;
 	unsigned long vios_cookie;
 	unsigned long hw_irq;
@@ -712,24 +732,6 @@ struct ibmvfc_async_crq_queue {
 	dma_addr_t msg_token;
 };
 
-union ibmvfc_iu {
-	struct ibmvfc_mad_common mad_common;
-	struct ibmvfc_npiv_login_mad npiv_login;
-	struct ibmvfc_npiv_logout_mad npiv_logout;
-	struct ibmvfc_discover_targets discover_targets;
-	struct ibmvfc_port_login plogi;
-	struct ibmvfc_process_login prli;
-	struct ibmvfc_move_login move_login;
-	struct ibmvfc_query_tgt query_tgt;
-	struct ibmvfc_implicit_logout implicit_logout;
-	struct ibmvfc_tmf tmf;
-	struct ibmvfc_cmd cmd;
-	struct ibmvfc_passthru_mad passthru;
-	struct ibmvfc_channel_enquiry channel_enquiry;
-	struct ibmvfc_channel_setup_mad channel_setup;
-	struct ibmvfc_connection_info connection_info;
-} __packed __aligned(8);
-
 enum ibmvfc_target_action {
 	IBMVFC_TGT_ACTION_NONE = 0,
 	IBMVFC_TGT_ACTION_INIT,
-- 
2.27.0