diff mbox series

[v2,15/17] ibmvfc: send Cancel MAD down each hw scsi channel

Message ID 20201202005329.4538-16-tyreld@linux.ibm.com
State New
Headers show
Series None | expand

Commit Message

Tyrel Datwyler Dec. 2, 2020, 12:53 a.m. UTC 
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.

Allocate event pointers for each possible scsi channel and assign an
event for each channel that requires a cancel. Wait for completion each
submitted cancel.

Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
 drivers/scsi/ibmvscsi/ibmvfc.c | 106 +++++++++++++++++++++------------
 1 file changed, 68 insertions(+), 38 deletions(-)

Comments

Brian King Dec. 2, 2020, 6:27 p.m. UTC | #1 
On 12/1/20 6:53 PM, Tyrel Datwyler wrote:
> 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.
> 
> Allocate event pointers for each possible scsi channel and assign an
> event for each channel that requires a cancel. Wait for completion each
> submitted cancel.
> 
> Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
> ---
>  drivers/scsi/ibmvscsi/ibmvfc.c | 106 +++++++++++++++++++++------------
>  1 file changed, 68 insertions(+), 38 deletions(-)
> 
> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
> index 0b6284020f06..97e8eed04b01 100644
> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c
> @@ -2339,32 +2339,52 @@ 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_event **evt_list;
> +	union ibmvfc_iu *rsp;
> +	int rsp_rc = 0;
>  	unsigned long flags;
>  	u16 status;
> +	int num_hwq = 1;
> +	int i;
> +	int ret = 0;
>  
>  	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;
> -			break;
> +	if (vhost->using_channels && vhost->scsi_scrqs.active_queues)
> +		num_hwq = vhost->scsi_scrqs.active_queues;
> +
> +	evt_list = kcalloc(num_hwq, sizeof(*evt_list), GFP_KERNE> +	rsp = kcalloc(num_hwq, sizeof(*rsp), GFP_KERNEL);

Can't this just go on the stack? We don't want to be allocating memory
during error recovery. Or, alternatively, you could put this in the
vhost structure and protect it with a mutex. We only have enough events
to single thread these anyway.

> +
> +	for (i = 0; i < num_hwq; i++) {
> +		sdev_printk(KERN_INFO, sdev, "Cancelling outstanding commands on queue %d.\n", i);

Prior to this patch, if there was nothing outstanding to the device and cancel_all was called,
no messages would get printed. This is changing that behavior. Is that intentional? Additionally,
it looks like this will get a lot more vebose, logging a message for each hw queue, regardless
of whether there was anything outstanding. Perhaps you want to move this down to after the check
for !found_evt?

> +
> +		found_evt = NULL;
> +		list_for_each_entry(evt, &vhost->sent, queue) {
> +			if (evt->cmnd && evt->cmnd->device == sdev && evt->hwq == i) {
> +				found_evt = evt;
> +				break;
> +			}
>  		}
> -	}
>
diff mbox series

Patch

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index 0b6284020f06..97e8eed04b01 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -2339,32 +2339,52 @@  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_event **evt_list;
+	union ibmvfc_iu *rsp;
+	int rsp_rc = 0;
 	unsigned long flags;
 	u16 status;
+	int num_hwq = 1;
+	int i;
+	int ret = 0;
 
 	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;
-			break;
+	if (vhost->using_channels && vhost->scsi_scrqs.active_queues)
+		num_hwq = vhost->scsi_scrqs.active_queues;
+
+	evt_list = kcalloc(num_hwq, sizeof(*evt_list), GFP_KERNEL);
+	rsp = kcalloc(num_hwq, sizeof(*rsp), GFP_KERNEL);
+
+	for (i = 0; i < num_hwq; i++) {
+		sdev_printk(KERN_INFO, sdev, "Cancelling outstanding commands on queue %d.\n", i);
+
+		found_evt = NULL;
+		list_for_each_entry(evt, &vhost->sent, queue) {
+			if (evt->cmnd && evt->cmnd->device == sdev && evt->hwq == i) {
+				found_evt = evt;
+				break;
+			}
 		}
-	}
 
-	if (!found_evt) {
-		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 (!found_evt) {
+			if (vhost->log_level > IBMVFC_DEFAULT_LOG_LEVEL)
+				sdev_printk(KERN_INFO, sdev, "No events found to cancel on queue %d\n", i);
+			continue;
+		}
 
-	if (vhost->logged_in) {
-		evt = ibmvfc_init_tmf(vhost, sdev, type);
-		evt->sync_iu = &rsp;
-		rsp_rc = ibmvfc_send_event(evt, vhost, default_timeout);
+
+		if (vhost->logged_in) {
+			evt_list[i] = ibmvfc_init_tmf(vhost, sdev, type);
+			evt_list[i]->hwq = i;
+			evt_list[i]->sync_iu = &rsp[i];
+			rsp_rc = ibmvfc_send_event(evt_list[i], vhost, default_timeout);
+			if (rsp_rc)
+				break;
+		} else {
+			rsp_rc = -EBUSY;
+			break;
+		}
 	}
 
 	spin_unlock_irqrestore(vhost->host->host_lock, flags);
@@ -2374,32 +2394,42 @@  static int ibmvfc_cancel_all(struct scsi_device *sdev, int type)
 		/* 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_mem;
 	}
 
-	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 (!evt_list[i])
+			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(&evt_list[i]->comp);
+		status = be16_to_cpu(rsp[i].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_mem;
+			default:
+				ret = -EIO;
+				goto free_mem;
+			};
+		}
 	}
 
 	sdev_printk(KERN_INFO, sdev, "Successfully cancelled outstanding commands\n");
-	return 0;
+free_mem:
+	spin_lock_irqsave(vhost->host->host_lock, flags);
+	for (i = 0; i < num_hwq; i++)
+		if (evt_list[i])
+			ibmvfc_free_event(evt_list[i]);
+	spin_unlock_irqrestore(vhost->host->host_lock, flags);
+	kfree(evt_list);
+	kfree(rsp);
+
+	return ret;
 }
 
 /**