diff mbox series

[v3,06/18] ibmvfc: add handlers to drain and complete Sub-CRQ responses

Message ID 20201203020806.14747-7-tyreld@linux.ibm.com (mailing list archive)
State Changes Requested
Headers show
Series ibmvfc: initial MQ development | expand

Commit Message

Tyrel Datwyler Dec. 3, 2020, 2:07 a.m. UTC
The logic for iterating over the Sub-CRQ responses is similiar to that
of the primary CRQ. Add the necessary handlers for processing those
responses.

Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
 drivers/scsi/ibmvscsi/ibmvfc.c | 80 ++++++++++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)

Comments

Brian King Dec. 4, 2020, 2:51 p.m. UTC | #1
On 12/2/20 8:07 PM, Tyrel Datwyler wrote:
> The logic for iterating over the Sub-CRQ responses is similiar to that
> of the primary CRQ. Add the necessary handlers for processing those
> responses.
> 
> Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
> ---
>  drivers/scsi/ibmvscsi/ibmvfc.c | 80 ++++++++++++++++++++++++++++++++++
>  1 file changed, 80 insertions(+)
> 
> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
> index e082935f56cf..b61ae1df21e5 100644
> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c
> @@ -3381,6 +3381,86 @@ static int ibmvfc_toggle_scrq_irq(struct ibmvfc_sub_queue *scrq, int enable)
>  	return rc;
>  }
>  
> +static void ibmvfc_handle_scrq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost)
> +{
> +	struct ibmvfc_event *evt = (struct ibmvfc_event *)be64_to_cpu(crq->ioba);
> +	unsigned long flags;
> +
> +	switch (crq->valid) {
> +	case IBMVFC_CRQ_CMD_RSP:
> +		break;
> +	case IBMVFC_CRQ_XPORT_EVENT:
> +		return;
> +	default:
> +		dev_err(vhost->dev, "Got and invalid message type 0x%02x\n", crq->valid);
> +		return;
> +	}
> +
> +	/* The only kind of payload CRQs we should get are responses to
> +	 * things we send. Make sure this response is to something we
> +	 * actually sent
> +	 */
> +	if (unlikely(!ibmvfc_valid_event(&vhost->pool, evt))) {
> +		dev_err(vhost->dev, "Returned correlation_token 0x%08llx is invalid!\n",
> +			crq->ioba);
> +		return;
> +	}
> +
> +	if (unlikely(atomic_read(&evt->free))) {
> +		dev_err(vhost->dev, "Received duplicate correlation_token 0x%08llx!\n",
> +			crq->ioba);
> +		return;
> +	}
> +
> +	del_timer(&evt->timer);
> +	list_del(&evt->queue);
> +	ibmvfc_trc_end(evt);> +	spin_unlock_irqrestore(vhost->host->host_lock, flags);

You can't do this here... You are grabbing the host lock in ibmvfc_drain_sub_crq
and saving the irqflags to a local in that function, then doing a spin_unlock_irqrestore
and restoring irqflags using an uninitialized local in this function...

I'm assuming this will get sorted out with the locking changes we've been discussing off-list...


> +	evt->done(evt);
> +	spin_lock_irqsave(vhost->host->host_lock, flags);
> +}
> +
> +static struct ibmvfc_crq *ibmvfc_next_scrq(struct ibmvfc_sub_queue *scrq)
> +{
> +	struct ibmvfc_crq *crq;
> +
> +	crq = &scrq->msgs[scrq->cur].crq;
> +	if (crq->valid & 0x80) {
> +		if (++scrq->cur == scrq->size)
> +			scrq->cur = 0;
> +		rmb();
> +	} else
> +		crq = NULL;
> +
> +	return crq;
> +}
> +
> +static void ibmvfc_drain_sub_crq(struct ibmvfc_sub_queue *scrq)
> +{
> +	struct ibmvfc_crq *crq;
> +	unsigned long flags;
> +	int done = 0;
> +
> +	spin_lock_irqsave(scrq->vhost->host->host_lock, flags);
> +	while (!done) {
> +		while ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
> +			ibmvfc_handle_scrq(crq, scrq->vhost);
> +			crq->valid = 0;
> +			wmb();
> +		}
> +
> +		ibmvfc_toggle_scrq_irq(scrq, 1);
> +		if ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
> +			ibmvfc_toggle_scrq_irq(scrq, 0);
> +			ibmvfc_handle_scrq(crq, scrq->vhost);
> +			crq->valid = 0;
> +			wmb();
> +		} else
> +			done = 1;
> +	}
> +	spin_unlock_irqrestore(scrq->vhost->host->host_lock, flags);
> +}
> +
>  /**
>   * ibmvfc_init_tgt - Set the next init job step for the target
>   * @tgt:		ibmvfc target struct
>
Tyrel Datwyler Dec. 5, 2020, 12:16 a.m. UTC | #2
On 12/4/20 6:51 AM, Brian King wrote:
> On 12/2/20 8:07 PM, Tyrel Datwyler wrote:
>> The logic for iterating over the Sub-CRQ responses is similiar to that
>> of the primary CRQ. Add the necessary handlers for processing those
>> responses.
>>
>> Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
>> ---
>>  drivers/scsi/ibmvscsi/ibmvfc.c | 80 ++++++++++++++++++++++++++++++++++
>>  1 file changed, 80 insertions(+)
>>
>> diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
>> index e082935f56cf..b61ae1df21e5 100644
>> --- a/drivers/scsi/ibmvscsi/ibmvfc.c
>> +++ b/drivers/scsi/ibmvscsi/ibmvfc.c
>> @@ -3381,6 +3381,86 @@ static int ibmvfc_toggle_scrq_irq(struct ibmvfc_sub_queue *scrq, int enable)
>>  	return rc;
>>  }
>>  
>> +static void ibmvfc_handle_scrq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost)
>> +{
>> +	struct ibmvfc_event *evt = (struct ibmvfc_event *)be64_to_cpu(crq->ioba);
>> +	unsigned long flags;
>> +
>> +	switch (crq->valid) {
>> +	case IBMVFC_CRQ_CMD_RSP:
>> +		break;
>> +	case IBMVFC_CRQ_XPORT_EVENT:
>> +		return;
>> +	default:
>> +		dev_err(vhost->dev, "Got and invalid message type 0x%02x\n", crq->valid);
>> +		return;
>> +	}
>> +
>> +	/* The only kind of payload CRQs we should get are responses to
>> +	 * things we send. Make sure this response is to something we
>> +	 * actually sent
>> +	 */
>> +	if (unlikely(!ibmvfc_valid_event(&vhost->pool, evt))) {
>> +		dev_err(vhost->dev, "Returned correlation_token 0x%08llx is invalid!\n",
>> +			crq->ioba);
>> +		return;
>> +	}
>> +
>> +	if (unlikely(atomic_read(&evt->free))) {
>> +		dev_err(vhost->dev, "Received duplicate correlation_token 0x%08llx!\n",
>> +			crq->ioba);
>> +		return;
>> +	}
>> +
>> +	del_timer(&evt->timer);
>> +	list_del(&evt->queue);
>> +	ibmvfc_trc_end(evt);> +	spin_unlock_irqrestore(vhost->host->host_lock, flags);
> 
> You can't do this here... You are grabbing the host lock in ibmvfc_drain_sub_crq
> and saving the irqflags to a local in that function, then doing a spin_unlock_irqrestore
> and restoring irqflags using an uninitialized local in this function...
> 
> I'm assuming this will get sorted out with the locking changes we've been discussing off-list...

Correct, moving to per-queue locks and flags stored in the queue struct.

-Tyrel

> 
> 
>> +	evt->done(evt);
>> +	spin_lock_irqsave(vhost->host->host_lock, flags);
>> +}
>> +
>> +static struct ibmvfc_crq *ibmvfc_next_scrq(struct ibmvfc_sub_queue *scrq)
>> +{
>> +	struct ibmvfc_crq *crq;
>> +
>> +	crq = &scrq->msgs[scrq->cur].crq;
>> +	if (crq->valid & 0x80) {
>> +		if (++scrq->cur == scrq->size)
>> +			scrq->cur = 0;
>> +		rmb();
>> +	} else
>> +		crq = NULL;
>> +
>> +	return crq;
>> +}
>> +
>> +static void ibmvfc_drain_sub_crq(struct ibmvfc_sub_queue *scrq)
>> +{
>> +	struct ibmvfc_crq *crq;
>> +	unsigned long flags;
>> +	int done = 0;
>> +
>> +	spin_lock_irqsave(scrq->vhost->host->host_lock, flags);
>> +	while (!done) {
>> +		while ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
>> +			ibmvfc_handle_scrq(crq, scrq->vhost);
>> +			crq->valid = 0;
>> +			wmb();
>> +		}
>> +
>> +		ibmvfc_toggle_scrq_irq(scrq, 1);
>> +		if ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
>> +			ibmvfc_toggle_scrq_irq(scrq, 0);
>> +			ibmvfc_handle_scrq(crq, scrq->vhost);
>> +			crq->valid = 0;
>> +			wmb();
>> +		} else
>> +			done = 1;
>> +	}
>> +	spin_unlock_irqrestore(scrq->vhost->host->host_lock, flags);
>> +}
>> +
>>  /**
>>   * ibmvfc_init_tgt - Set the next init job step for the target
>>   * @tgt:		ibmvfc target struct
>>
> 
>
diff mbox series

Patch

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c
index e082935f56cf..b61ae1df21e5 100644
--- a/drivers/scsi/ibmvscsi/ibmvfc.c
+++ b/drivers/scsi/ibmvscsi/ibmvfc.c
@@ -3381,6 +3381,86 @@  static int ibmvfc_toggle_scrq_irq(struct ibmvfc_sub_queue *scrq, int enable)
 	return rc;
 }
 
+static void ibmvfc_handle_scrq(struct ibmvfc_crq *crq, struct ibmvfc_host *vhost)
+{
+	struct ibmvfc_event *evt = (struct ibmvfc_event *)be64_to_cpu(crq->ioba);
+	unsigned long flags;
+
+	switch (crq->valid) {
+	case IBMVFC_CRQ_CMD_RSP:
+		break;
+	case IBMVFC_CRQ_XPORT_EVENT:
+		return;
+	default:
+		dev_err(vhost->dev, "Got and invalid message type 0x%02x\n", crq->valid);
+		return;
+	}
+
+	/* The only kind of payload CRQs we should get are responses to
+	 * things we send. Make sure this response is to something we
+	 * actually sent
+	 */
+	if (unlikely(!ibmvfc_valid_event(&vhost->pool, evt))) {
+		dev_err(vhost->dev, "Returned correlation_token 0x%08llx is invalid!\n",
+			crq->ioba);
+		return;
+	}
+
+	if (unlikely(atomic_read(&evt->free))) {
+		dev_err(vhost->dev, "Received duplicate correlation_token 0x%08llx!\n",
+			crq->ioba);
+		return;
+	}
+
+	del_timer(&evt->timer);
+	list_del(&evt->queue);
+	ibmvfc_trc_end(evt);
+	spin_unlock_irqrestore(vhost->host->host_lock, flags);
+	evt->done(evt);
+	spin_lock_irqsave(vhost->host->host_lock, flags);
+}
+
+static struct ibmvfc_crq *ibmvfc_next_scrq(struct ibmvfc_sub_queue *scrq)
+{
+	struct ibmvfc_crq *crq;
+
+	crq = &scrq->msgs[scrq->cur].crq;
+	if (crq->valid & 0x80) {
+		if (++scrq->cur == scrq->size)
+			scrq->cur = 0;
+		rmb();
+	} else
+		crq = NULL;
+
+	return crq;
+}
+
+static void ibmvfc_drain_sub_crq(struct ibmvfc_sub_queue *scrq)
+{
+	struct ibmvfc_crq *crq;
+	unsigned long flags;
+	int done = 0;
+
+	spin_lock_irqsave(scrq->vhost->host->host_lock, flags);
+	while (!done) {
+		while ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
+			ibmvfc_handle_scrq(crq, scrq->vhost);
+			crq->valid = 0;
+			wmb();
+		}
+
+		ibmvfc_toggle_scrq_irq(scrq, 1);
+		if ((crq = ibmvfc_next_scrq(scrq)) != NULL) {
+			ibmvfc_toggle_scrq_irq(scrq, 0);
+			ibmvfc_handle_scrq(crq, scrq->vhost);
+			crq->valid = 0;
+			wmb();
+		} else
+			done = 1;
+	}
+	spin_unlock_irqrestore(scrq->vhost->host->host_lock, flags);
+}
+
 /**
  * ibmvfc_init_tgt - Set the next init job step for the target
  * @tgt:		ibmvfc target struct