[SLOF] [PATCH v1 20/27] virtio: make virtio_fill_desc 1.0 aware

[Nikunj A Dadhania]

Alexey Kardashevskiy <aik at ozlabs.ru> writes:

> On 01/13/2016 10:17 PM, Nikunj A Dadhania wrote:
>> Signed-off-by: Nikunj A Dadhania <nikunj at linux.vnet.ibm.com>
>> ---
>>   lib/libvirtio/virtio-blk.c |  6 +++---
>>   lib/libvirtio/virtio.c     | 21 +++++++++++++++------
>>   lib/libvirtio/virtio.h     |  2 +-
>>   3 files changed, 19 insertions(+), 10 deletions(-)
>>
>> diff --git a/lib/libvirtio/virtio-blk.c b/lib/libvirtio/virtio-blk.c
>> index 2d8982d..19819cf 100644
>> --- a/lib/libvirtio/virtio-blk.c
>> +++ b/lib/libvirtio/virtio-blk.c
>> @@ -152,17 +152,17 @@ virtioblk_read(struct virtio_device *dev, char *buf, long blocknum, long cnt)
>>
>>   	/* Set up virtqueue descriptor for header */
>>   	desc = &vq_desc[id];
>> -	virtio_fill_desc(desc, (uint64_t)&blkhdr, sizeof(struct virtio_blk_req),
>> +	virtio_fill_desc(desc, 0, (uint64_t)&blkhdr, sizeof(struct virtio_blk_req),
>>   		  VRING_DESC_F_NEXT, (id + 1) % vq_size);
>>
>>   	/* Set up virtqueue descriptor for data */
>>   	desc = &vq_desc[(id + 1) % vq_size];
>> -	virtio_fill_desc(desc, (uint64_t)buf, cnt * blk_size,
>> +	virtio_fill_desc(desc, 0, (uint64_t)buf, cnt * blk_size,
>>   		  VRING_DESC_F_NEXT | VRING_DESC_F_WRITE, (id + 2) % vq_size);
>>
>>   	/* Set up virtqueue descriptor for status */
>>   	desc = &vq_desc[(id + 2) % vq_size];
>> -	virtio_fill_desc(desc, (uint64_t)&status, 1, VRING_DESC_F_WRITE, 0);
>> +	virtio_fill_desc(desc, 0, (uint64_t)&status, 1, VRING_DESC_F_WRITE, 0);
>>
>>   	vq_avail->ring[vq_avail->idx % vq_size] = id;
>>   	mb();
>> diff --git a/lib/libvirtio/virtio.c b/lib/libvirtio/virtio.c
>> index e81d78e..e1ab97f 100644
>> --- a/lib/libvirtio/virtio.c
>> +++ b/lib/libvirtio/virtio.c
>> @@ -304,15 +304,24 @@ struct vring_used *virtio_get_vring_used(struct virtio_device *dev, int queue)
>>   	}
>>   }
>>
>> -
>> -void virtio_fill_desc(struct vring_desc *desc,
>> +/**
>> + * Fill the virtio ring descriptor depending on the legacy mode or virtio 1.0
>> + */
>> +void virtio_fill_desc(struct vring_desc *desc, uint32_t is_modern,
>
>
> s/uint32_t is_modern/bool is_modern/

Sure

> And it belongs to 03/27. Or 03/27 is better be merged into this.

There are common changes that I did not want to mix with virtio
1.0. That was the reason to separate this.

> Up to you. 
> Please avoid changing same bits of code several times in the same patchset, 
> it is confusing.

There will be unrelated changes in the driver  if I mix them in 03 or
bring them here.

>
>
>>                         uint64_t addr, uint32_t len,
>>                         uint16_t flags, uint16_t next)
>>   {
>> -	desc->addr = addr;
>> -	desc->len = len;
>> -	desc->flags = flags;
>> -	desc->next = next;
>> +	if (is_modern) {
>> +		desc->addr = cpu_to_le64(addr);
>> +		desc->len = cpu_to_le32(len);
>> +		desc->flags = cpu_to_le16(flags);
>> +		desc->next = cpu_to_le16(next);
>> +	} else {
>> +		desc->addr = addr;
>> +		desc->len = len;
>> +		desc->flags = flags;
>> +		desc->next = next;
>> +	}
>>   }
>>
>>   /**
>> diff --git a/lib/libvirtio/virtio.h b/lib/libvirtio/virtio.h
>> index 07bd28c..afa3c9c 100644
>> --- a/lib/libvirtio/virtio.h
>> +++ b/lib/libvirtio/virtio.h
>> @@ -113,7 +113,7 @@ 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);
>> -extern void virtio_fill_desc(struct vring_desc *desc,
>> +extern void virtio_fill_desc(struct vring_desc *desc, uint32_t is_modern,
>>                                uint64_t addr, uint32_t len,
>>                                uint16_t flags, uint16_t next);
>>   extern int virtio_queue_init_vq(struct virtio_device *dev, struct vqs *vq, unsigned int id);
>>
>
>
> -- 
> Alexey