Re: [Qemu-devel] [PULL 20/22] virtio: introduce virtqueue_unmap_sg()

[Jason Wang <jasowang@redhat.com>]

On 09/25/2015 02:58 AM, Michael S. Tsirkin wrote:
> On Thu, Sep 24, 2015 at 04:21:02PM +0300, Michael S. Tsirkin wrote:
>> From: Jason Wang <jasowang@redhat.com>
>>
>> Factor out sg unmapping logic. This will be reused by the patch that
>> can discard descriptor.
>>
>> Cc: Michael S. Tsirkin <mst@redhat.com>
>> Signed-off-by: Jason Wang <jasowang@redhat.com>
>> Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
>> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
>> ---
>>  hw/virtio/virtio.c | 15 ++++++++++-----
>>  1 file changed, 10 insertions(+), 5 deletions(-)
>>
>> diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
>> index 7504f8b..d6a2bca 100644
>> --- a/hw/virtio/virtio.c
>> +++ b/hw/virtio/virtio.c
>> @@ -244,15 +244,12 @@ int virtio_queue_empty(VirtQueue *vq)
>>      return vring_avail_idx(vq) == vq->last_avail_idx;
>>  }
>>  
>> -void virtqueue_fill(VirtQueue *vq, const VirtQueueElement *elem,
>> -                    unsigned int len, unsigned int idx)
>> +static void virtqueue_unmap_sg(VirtQueue *vq, const VirtQueueElement *elem,
>> +                               unsigned int len)
>>  {
>>      unsigned int offset;
>>      int i;
>>  
>> -    trace_virtqueue_fill(vq, elem, len, idx);
>> -
>> -    offset = 0;
>>      for (i = 0; i < elem->in_num; i++) {
>>          size_t size = MIN(len - offset, elem->in_sg[i].iov_len);
>>  
> This part causes an unitialized variable warning to appear.
> I dropped this from the pull request.
> Jason, could you look into this please?
>

Will fix this in V2.

Thanks