[SLOF] [PATCH v1 08/27] virtio: make virtio_get_qsize 1.0 aware

[Nikunj A Dadhania]

Alexey Kardashevskiy <aik at ozlabs.ru> writes:

> On 01/13/2016 10:16 PM, Nikunj A Dadhania wrote:
>> Also return unsigned int
>
> Why?

Size is not negative :-)

>
>
>>
>> Signed-off-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
>> ---
>>   lib/libvirtio/virtio.c | 15 +++++++++++----
>>   lib/libvirtio/virtio.h |  2 +-
>>   2 files changed, 12 insertions(+), 5 deletions(-)
>>
>> diff --git a/lib/libvirtio/virtio.c b/lib/libvirtio/virtio.c
>> index bcf050b..77676c7 100644
>> --- a/lib/libvirtio/virtio.c
>> +++ b/lib/libvirtio/virtio.c
>> @@ -185,17 +185,24 @@ unsigned long virtio_vring_size(unsigned int qsize)
>>    * @param   queue virtio queue number
>>    * @return  number of elements
>>    */
>> -int virtio_get_qsize(struct virtio_device *dev, int queue)
>> +unsigned int virtio_get_qsize(struct virtio_device *dev, int queue)
>>   {
>> -	int size = 0;
>> +	unsigned int size = 0;
>>
>> -	if (dev->type == VIRTIO_TYPE_PCI) {
>> +	if (dev->type != VIRTIO_TYPE_PCI)
>> +		return 0;
>> +	if (dev->is_modern) {
>> +		void *addr = dev->common.addr + offset_of(struct virtio_dev_common, q_select);
>> +		ci_write_16(addr, cpu_to_le16(queue));
>> +		eieio();
>> +		size = le16_to_cpu(ci_read_16(addr + 2));
>
>
> Please add commit log explaining this magic.

Sure.

>
>
>> +	}
>> +	else {
>>   		ci_write_16(dev->base+VIRTIOHDR_QUEUE_SELECT,
>>   			    cpu_to_le16(queue));
>>   		eieio();
>>   		size = le16_to_cpu(ci_read_16(dev->base+VIRTIOHDR_QUEUE_SIZE));
>>   	}
>> -
>
> Unrelated change.

Yep.

>
>
>>   	return size;
>>   }
>>
>> diff --git a/lib/libvirtio/virtio.h b/lib/libvirtio/virtio.h
>> index eee3144..537862b 100644
>> --- a/lib/libvirtio/virtio.h
>> +++ b/lib/libvirtio/virtio.h
>> @@ -107,7 +107,7 @@ struct vqs {
>>   #define VQ_ALIGN(addr)	(((addr) + 0xfff) & ~0xfff)
>>
>>   extern unsigned long virtio_vring_size(unsigned int qsize);
>> -extern int virtio_get_qsize(struct virtio_device *dev, int queue);
>> +extern unsigned int virtio_get_qsize(struct virtio_device *dev, int queue);
>>   extern struct vring_desc *virtio_get_vring_desc(struct virtio_device *dev, int queue);
>>   extern struct vring_avail *virtio_get_vring_avail(struct virtio_device *dev, int queue);
>>   extern struct vring_used *virtio_get_vring_used(struct virtio_device *dev, int queue);
>>
>
>
> -- 
> Alexey