diff mbox

[2/6] ibmvscsi: Add and use enums for valid CRQ header values

Message ID 1454542114-1797-3-git-send-email-tyreld@linux.vnet.ibm.com (mailing list archive)
State Changes Requested, archived
Headers show

Commit Message

Tyrel Datwyler Feb. 3, 2016, 11:28 p.m. UTC
The PAPR defines four valid header values for the first byte of a
CRQ message. Namely, an unused/empty message (0x00), a valid
command/response entry (0x80), a valid initialization entry (0xC0),
and a transport event (0xFF). Define these values as enums and use
them in the code in place of their magic number equivalents.

Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
---
 drivers/scsi/ibmvscsi/ibmvscsi.c | 14 +++++++-------
 drivers/scsi/ibmvscsi/viosrp.h   |  7 +++++++
 2 files changed, 14 insertions(+), 7 deletions(-)

Comments

Johannes Thumshirn Feb. 4, 2016, 8:39 a.m. UTC | #1
On Wed, Feb 03, 2016 at 05:28:30PM -0600, Tyrel Datwyler wrote:
> The PAPR defines four valid header values for the first byte of a
> CRQ message. Namely, an unused/empty message (0x00), a valid
> command/response entry (0x80), a valid initialization entry (0xC0),
> and a transport event (0xFF). Define these values as enums and use
> them in the code in place of their magic number equivalents.
> 
> Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
> ---
>  drivers/scsi/ibmvscsi/ibmvscsi.c | 14 +++++++-------
>  drivers/scsi/ibmvscsi/viosrp.h   |  7 +++++++
>  2 files changed, 14 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
> index adfef9d..176260d 100644
> --- a/drivers/scsi/ibmvscsi/ibmvscsi.c
> +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
> @@ -182,7 +182,7 @@ static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
>  
>  	spin_lock_irqsave(&queue->lock, flags);
>  	crq = &queue->msgs[queue->cur];
> -	if (crq->valid & 0x80) {
> +	if (crq->valid & VIOSRP_CRQ_VALID) {
>  		if (++queue->cur == queue->size)
>  			queue->cur = 0;
>  
> @@ -231,7 +231,7 @@ static void ibmvscsi_task(void *data)
>  		/* Pull all the valid messages off the CRQ */
>  		while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
>  			ibmvscsi_handle_crq(crq, hostdata);
> -			crq->valid = 0x00;
> +			crq->valid = VIOSRP_CRQ_FREE;
>  		}
>  
>  		vio_enable_interrupts(vdev);
> @@ -239,7 +239,7 @@ static void ibmvscsi_task(void *data)
>  		if (crq != NULL) {
>  			vio_disable_interrupts(vdev);
>  			ibmvscsi_handle_crq(crq, hostdata);
> -			crq->valid = 0x00;
> +			crq->valid = VIOSRP_CRQ_FREE;
>  		} else {
>  			done = 1;
>  		}
> @@ -474,7 +474,7 @@ static int initialize_event_pool(struct event_pool *pool,
>  		struct srp_event_struct *evt = &pool->events[i];
>  		memset(&evt->crq, 0x00, sizeof(evt->crq));
>  		atomic_set(&evt->free, 1);
> -		evt->crq.valid = 0x80;
> +		evt->crq.valid = VIOSRP_CRQ_VALID;
>  		evt->crq.IU_length = cpu_to_be16(sizeof(*evt->xfer_iu));
>  		evt->crq.IU_data_ptr = cpu_to_be64(pool->iu_token +
>  			sizeof(*evt->xfer_iu) * i);
> @@ -1767,7 +1767,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>  	struct srp_event_struct *evt_struct =
>  			(__force struct srp_event_struct *)crq->IU_data_ptr;
>  	switch (crq->valid) {
> -	case 0xC0:		/* initialization */
> +	case VIOSRP_CRQ_INIT:		/* initialization */
>  		switch (crq->format) {
>  		case 0x01:	/* Initialization message */
>  			dev_info(hostdata->dev, "partner initialized\n");
> @@ -1791,7 +1791,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>  			dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
>  		}
>  		return;
> -	case 0xFF:	/* Hypervisor telling us the connection is closed */
> +	case VIOSRP_CRQ_TRANSPORT:	/* Hypervisor telling us the connection is closed */
>  		scsi_block_requests(hostdata->host);
>  		atomic_set(&hostdata->request_limit, 0);
>  		if (crq->format == 0x06) {
> @@ -1807,7 +1807,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>  			ibmvscsi_reset_host(hostdata);
>  		}
>  		return;
> -	case 0x80:		/* real payload */
> +	case VIOSRP_CRQ_VALID:		/* real payload */
>  		break;
>  	default:
>  		dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
> diff --git a/drivers/scsi/ibmvscsi/viosrp.h b/drivers/scsi/ibmvscsi/viosrp.h
> index d1044e9..17f2de0 100644
> --- a/drivers/scsi/ibmvscsi/viosrp.h
> +++ b/drivers/scsi/ibmvscsi/viosrp.h
> @@ -51,6 +51,13 @@ union srp_iu {
>  	u8 reserved[SRP_MAX_IU_LEN];
>  };
>  
> +enum viosrp_crq_headers {
> +	VIOSRP_CRQ_FREE = 0x00,
> +	VIOSRP_CRQ_VALID = 0x80,
> +	VIOSRP_CRQ_INIT = 0xC0,
> +	VIOSRP_CRQ_TRANSPORT = 0xFF
> +};
> +
>  enum viosrp_crq_formats {
>  	VIOSRP_SRP_FORMAT = 0x01,
>  	VIOSRP_MAD_FORMAT = 0x02,
> -- 
> 2.5.0
> 
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Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Manoj Kumar Feb. 4, 2016, 7:55 p.m. UTC | #2
On 2/3/2016 5:28 PM, Tyrel Datwyler wrote:
> The PAPR defines four valid header values for the first byte of a
> CRQ message. Namely, an unused/empty message (0x00), a valid
> command/response entry (0x80), a valid initialization entry (0xC0),
> and a transport event (0xFF). Define these values as enums and use
> them in the code in place of their magic number equivalents.
>
> Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
> ---
>   drivers/scsi/ibmvscsi/ibmvscsi.c | 14 +++++++-------
>   drivers/scsi/ibmvscsi/viosrp.h   |  7 +++++++
>   2 files changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
> index adfef9d..176260d 100644
> --- a/drivers/scsi/ibmvscsi/ibmvscsi.c
> +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
> @@ -182,7 +182,7 @@ static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
>
>   	spin_lock_irqsave(&queue->lock, flags);
>   	crq = &queue->msgs[queue->cur];
> -	if (crq->valid & 0x80) {
> +	if (crq->valid & VIOSRP_CRQ_VALID) {

After the switch to enums, bitwise operators are a bit misleading.
Especially in this case since multiple values would satisfy this
condition: VIOSRP_CRQ_VALID, VIOSRP_CRQ_INIT and
VIOSRP_CRQ_TRANSPORT.

If 'valid' will only have one of these four enums defined, would
this be better written as:

	if (crq->valid != VIOSRP_CRQ_FREE)

>   		if (++queue->cur == queue->size)
>   			queue->cur = 0;
>
> @@ -231,7 +231,7 @@ static void ibmvscsi_task(void *data)
>   		/* Pull all the valid messages off the CRQ */
>   		while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
>   			ibmvscsi_handle_crq(crq, hostdata);
> -			crq->valid = 0x00;
> +			crq->valid = VIOSRP_CRQ_FREE;
>   		}
>
>   		vio_enable_interrupts(vdev);
> @@ -239,7 +239,7 @@ static void ibmvscsi_task(void *data)
>   		if (crq != NULL) {
>   			vio_disable_interrupts(vdev);
>   			ibmvscsi_handle_crq(crq, hostdata);
> -			crq->valid = 0x00;
> +			crq->valid = VIOSRP_CRQ_FREE;
>   		} else {
>   			done = 1;
>   		}
> @@ -474,7 +474,7 @@ static int initialize_event_pool(struct event_pool *pool,
>   		struct srp_event_struct *evt = &pool->events[i];
>   		memset(&evt->crq, 0x00, sizeof(evt->crq));
>   		atomic_set(&evt->free, 1);
> -		evt->crq.valid = 0x80;
> +		evt->crq.valid = VIOSRP_CRQ_VALID;
>   		evt->crq.IU_length = cpu_to_be16(sizeof(*evt->xfer_iu));
>   		evt->crq.IU_data_ptr = cpu_to_be64(pool->iu_token +
>   			sizeof(*evt->xfer_iu) * i);
> @@ -1767,7 +1767,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>   	struct srp_event_struct *evt_struct =
>   			(__force struct srp_event_struct *)crq->IU_data_ptr;
>   	switch (crq->valid) {
> -	case 0xC0:		/* initialization */
> +	case VIOSRP_CRQ_INIT:		/* initialization */
>   		switch (crq->format) {
>   		case 0x01:	/* Initialization message */
>   			dev_info(hostdata->dev, "partner initialized\n");
> @@ -1791,7 +1791,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>   			dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
>   		}
>   		return;
> -	case 0xFF:	/* Hypervisor telling us the connection is closed */
> +	case VIOSRP_CRQ_TRANSPORT:	/* Hypervisor telling us the connection is closed */
>   		scsi_block_requests(hostdata->host);
>   		atomic_set(&hostdata->request_limit, 0);
>   		if (crq->format == 0x06) {
> @@ -1807,7 +1807,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>   			ibmvscsi_reset_host(hostdata);
>   		}
>   		return;
> -	case 0x80:		/* real payload */
> +	case VIOSRP_CRQ_VALID:		/* real payload */
>   		break;
>   	default:
>   		dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
> diff --git a/drivers/scsi/ibmvscsi/viosrp.h b/drivers/scsi/ibmvscsi/viosrp.h
> index d1044e9..17f2de0 100644
> --- a/drivers/scsi/ibmvscsi/viosrp.h
> +++ b/drivers/scsi/ibmvscsi/viosrp.h
> @@ -51,6 +51,13 @@ union srp_iu {
>   	u8 reserved[SRP_MAX_IU_LEN];
>   };
>
> +enum viosrp_crq_headers {
> +	VIOSRP_CRQ_FREE = 0x00,
> +	VIOSRP_CRQ_VALID = 0x80,
> +	VIOSRP_CRQ_INIT = 0xC0,
> +	VIOSRP_CRQ_TRANSPORT = 0xFF
> +};
> +
>   enum viosrp_crq_formats {
>   	VIOSRP_SRP_FORMAT = 0x01,
>   	VIOSRP_MAD_FORMAT = 0x02,
>

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Tyrel Datwyler Feb. 4, 2016, 9:25 p.m. UTC | #3
On 02/04/2016 11:55 AM, Manoj Kumar wrote:
> On 2/3/2016 5:28 PM, Tyrel Datwyler wrote:
>> The PAPR defines four valid header values for the first byte of a
>> CRQ message. Namely, an unused/empty message (0x00), a valid
>> command/response entry (0x80), a valid initialization entry (0xC0),
>> and a transport event (0xFF). Define these values as enums and use
>> them in the code in place of their magic number equivalents.
>>
>> Signed-off-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com>
>> ---
>>   drivers/scsi/ibmvscsi/ibmvscsi.c | 14 +++++++-------
>>   drivers/scsi/ibmvscsi/viosrp.h   |  7 +++++++
>>   2 files changed, 14 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
>> index adfef9d..176260d 100644
>> --- a/drivers/scsi/ibmvscsi/ibmvscsi.c
>> +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
>> @@ -182,7 +182,7 @@ static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
>>
>>   	spin_lock_irqsave(&queue->lock, flags);
>>   	crq = &queue->msgs[queue->cur];
>> -	if (crq->valid & 0x80) {
>> +	if (crq->valid & VIOSRP_CRQ_VALID) {
> 
> After the switch to enums, bitwise operators are a bit misleading.
> Especially in this case since multiple values would satisfy this
> condition: VIOSRP_CRQ_VALID, VIOSRP_CRQ_INIT and
> VIOSRP_CRQ_TRANSPORT.

Yeah, I can see how that is confusing. Since, all three possible valid
crq message types have the first bit set I think this was originally a
cute hack to grab anything that was likely valid. Then in
ibmvscsi_handle_crq() we explicitly match the full header value in a
switch statement logging anything that turned out actually invalid.

> 
> If 'valid' will only have one of these four enums defined, would
> this be better written as:
> 
> 	if (crq->valid != VIOSRP_CRQ_FREE)

This definitely would make the logic easier to read and follow. Also,
this would make sure any crq with an invalid header that doesn't have
its first bit set will also be logged by the ibmvscsi_handle_crq()
switch statement default block and not silently ignored.

-Tyrel

> 
>>   		if (++queue->cur == queue->size)
>>   			queue->cur = 0;
>>
>> @@ -231,7 +231,7 @@ static void ibmvscsi_task(void *data)
>>   		/* Pull all the valid messages off the CRQ */
>>   		while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
>>   			ibmvscsi_handle_crq(crq, hostdata);
>> -			crq->valid = 0x00;
>> +			crq->valid = VIOSRP_CRQ_FREE;
>>   		}
>>
>>   		vio_enable_interrupts(vdev);
>> @@ -239,7 +239,7 @@ static void ibmvscsi_task(void *data)
>>   		if (crq != NULL) {
>>   			vio_disable_interrupts(vdev);
>>   			ibmvscsi_handle_crq(crq, hostdata);
>> -			crq->valid = 0x00;
>> +			crq->valid = VIOSRP_CRQ_FREE;
>>   		} else {
>>   			done = 1;
>>   		}
>> @@ -474,7 +474,7 @@ static int initialize_event_pool(struct event_pool *pool,
>>   		struct srp_event_struct *evt = &pool->events[i];
>>   		memset(&evt->crq, 0x00, sizeof(evt->crq));
>>   		atomic_set(&evt->free, 1);
>> -		evt->crq.valid = 0x80;
>> +		evt->crq.valid = VIOSRP_CRQ_VALID;
>>   		evt->crq.IU_length = cpu_to_be16(sizeof(*evt->xfer_iu));
>>   		evt->crq.IU_data_ptr = cpu_to_be64(pool->iu_token +
>>   			sizeof(*evt->xfer_iu) * i);
>> @@ -1767,7 +1767,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>>   	struct srp_event_struct *evt_struct =
>>   			(__force struct srp_event_struct *)crq->IU_data_ptr;
>>   	switch (crq->valid) {
>> -	case 0xC0:		/* initialization */
>> +	case VIOSRP_CRQ_INIT:		/* initialization */
>>   		switch (crq->format) {
>>   		case 0x01:	/* Initialization message */
>>   			dev_info(hostdata->dev, "partner initialized\n");
>> @@ -1791,7 +1791,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>>   			dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
>>   		}
>>   		return;
>> -	case 0xFF:	/* Hypervisor telling us the connection is closed */
>> +	case VIOSRP_CRQ_TRANSPORT:	/* Hypervisor telling us the connection is closed */
>>   		scsi_block_requests(hostdata->host);
>>   		atomic_set(&hostdata->request_limit, 0);
>>   		if (crq->format == 0x06) {
>> @@ -1807,7 +1807,7 @@ static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
>>   			ibmvscsi_reset_host(hostdata);
>>   		}
>>   		return;
>> -	case 0x80:		/* real payload */
>> +	case VIOSRP_CRQ_VALID:		/* real payload */
>>   		break;
>>   	default:
>>   		dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
>> diff --git a/drivers/scsi/ibmvscsi/viosrp.h b/drivers/scsi/ibmvscsi/viosrp.h
>> index d1044e9..17f2de0 100644
>> --- a/drivers/scsi/ibmvscsi/viosrp.h
>> +++ b/drivers/scsi/ibmvscsi/viosrp.h
>> @@ -51,6 +51,13 @@ union srp_iu {
>>   	u8 reserved[SRP_MAX_IU_LEN];
>>   };
>>
>> +enum viosrp_crq_headers {
>> +	VIOSRP_CRQ_FREE = 0x00,
>> +	VIOSRP_CRQ_VALID = 0x80,
>> +	VIOSRP_CRQ_INIT = 0xC0,
>> +	VIOSRP_CRQ_TRANSPORT = 0xFF
>> +};
>> +
>>   enum viosrp_crq_formats {
>>   	VIOSRP_SRP_FORMAT = 0x01,
>>   	VIOSRP_MAD_FORMAT = 0x02,
>>
> 
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev
> 

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Manoj Kumar Feb. 9, 2016, 5:41 p.m. UTC | #4
> Yeah, I can see how that is confusing. Since, all three possible valid
> crq message types have the first bit set I think this was originally a
> cute hack to grab anything that was likely valid. Then in
> ibmvscsi_handle_crq() we explicitly match the full header value in a
> switch statement logging anything that turned out actually invalid.
>
>>
>> If 'valid' will only have one of these four enums defined, would
>> this be better written as:
>>
>> 	if (crq->valid != VIOSRP_CRQ_FREE)
>
> This definitely would make the logic easier to read and follow. Also,
> this would make sure any crq with an invalid header that doesn't have
> its first bit set will also be logged by the ibmvscsi_handle_crq()
> switch statement default block and not silently ignored.
>
> -Tyrel

Sounds good, Tyrel. Does this mean I should expect a v2 of this patch
series?

- Manoj N. Kumar

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Tyrel Datwyler Feb. 9, 2016, 6:27 p.m. UTC | #5
On 02/09/2016 09:41 AM, Manoj Kumar wrote:
>> Yeah, I can see how that is confusing. Since, all three possible valid
>> crq message types have the first bit set I think this was originally a
>> cute hack to grab anything that was likely valid. Then in
>> ibmvscsi_handle_crq() we explicitly match the full header value in a
>> switch statement logging anything that turned out actually invalid.
>>
>>>
>>> If 'valid' will only have one of these four enums defined, would
>>> this be better written as:
>>>
>>> 	if (crq->valid != VIOSRP_CRQ_FREE)
>>
>> This definitely would make the logic easier to read and follow. Also,
>> this would make sure any crq with an invalid header that doesn't have
>> its first bit set will also be logged by the ibmvscsi_handle_crq()
>> switch statement default block and not silently ignored.
>>
>> -Tyrel
> 
> Sounds good, Tyrel. Does this mean I should expect a v2 of this patch
> series?
> 
> - Manoj N. Kumar

Haven't had a chance to clean up and resubmit, but yes there will be a
v2 coming along soon.

-Tyrel

> 
> _______________________________________________
> Linuxppc-dev mailing list
> Linuxppc-dev@lists.ozlabs.org
> https://lists.ozlabs.org/listinfo/linuxppc-dev
> 

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diff mbox

Patch

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index adfef9d..176260d 100644
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -182,7 +182,7 @@  static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
 
 	spin_lock_irqsave(&queue->lock, flags);
 	crq = &queue->msgs[queue->cur];
-	if (crq->valid & 0x80) {
+	if (crq->valid & VIOSRP_CRQ_VALID) {
 		if (++queue->cur == queue->size)
 			queue->cur = 0;
 
@@ -231,7 +231,7 @@  static void ibmvscsi_task(void *data)
 		/* Pull all the valid messages off the CRQ */
 		while ((crq = crq_queue_next_crq(&hostdata->queue)) != NULL) {
 			ibmvscsi_handle_crq(crq, hostdata);
-			crq->valid = 0x00;
+			crq->valid = VIOSRP_CRQ_FREE;
 		}
 
 		vio_enable_interrupts(vdev);
@@ -239,7 +239,7 @@  static void ibmvscsi_task(void *data)
 		if (crq != NULL) {
 			vio_disable_interrupts(vdev);
 			ibmvscsi_handle_crq(crq, hostdata);
-			crq->valid = 0x00;
+			crq->valid = VIOSRP_CRQ_FREE;
 		} else {
 			done = 1;
 		}
@@ -474,7 +474,7 @@  static int initialize_event_pool(struct event_pool *pool,
 		struct srp_event_struct *evt = &pool->events[i];
 		memset(&evt->crq, 0x00, sizeof(evt->crq));
 		atomic_set(&evt->free, 1);
-		evt->crq.valid = 0x80;
+		evt->crq.valid = VIOSRP_CRQ_VALID;
 		evt->crq.IU_length = cpu_to_be16(sizeof(*evt->xfer_iu));
 		evt->crq.IU_data_ptr = cpu_to_be64(pool->iu_token +
 			sizeof(*evt->xfer_iu) * i);
@@ -1767,7 +1767,7 @@  static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
 	struct srp_event_struct *evt_struct =
 			(__force struct srp_event_struct *)crq->IU_data_ptr;
 	switch (crq->valid) {
-	case 0xC0:		/* initialization */
+	case VIOSRP_CRQ_INIT:		/* initialization */
 		switch (crq->format) {
 		case 0x01:	/* Initialization message */
 			dev_info(hostdata->dev, "partner initialized\n");
@@ -1791,7 +1791,7 @@  static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
 			dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
 		}
 		return;
-	case 0xFF:	/* Hypervisor telling us the connection is closed */
+	case VIOSRP_CRQ_TRANSPORT:	/* Hypervisor telling us the connection is closed */
 		scsi_block_requests(hostdata->host);
 		atomic_set(&hostdata->request_limit, 0);
 		if (crq->format == 0x06) {
@@ -1807,7 +1807,7 @@  static void ibmvscsi_handle_crq(struct viosrp_crq *crq,
 			ibmvscsi_reset_host(hostdata);
 		}
 		return;
-	case 0x80:		/* real payload */
+	case VIOSRP_CRQ_VALID:		/* real payload */
 		break;
 	default:
 		dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
diff --git a/drivers/scsi/ibmvscsi/viosrp.h b/drivers/scsi/ibmvscsi/viosrp.h
index d1044e9..17f2de0 100644
--- a/drivers/scsi/ibmvscsi/viosrp.h
+++ b/drivers/scsi/ibmvscsi/viosrp.h
@@ -51,6 +51,13 @@  union srp_iu {
 	u8 reserved[SRP_MAX_IU_LEN];
 };
 
+enum viosrp_crq_headers {
+	VIOSRP_CRQ_FREE = 0x00,
+	VIOSRP_CRQ_VALID = 0x80,
+	VIOSRP_CRQ_INIT = 0xC0,
+	VIOSRP_CRQ_TRANSPORT = 0xFF
+};
+
 enum viosrp_crq_formats {
 	VIOSRP_SRP_FORMAT = 0x01,
 	VIOSRP_MAD_FORMAT = 0x02,