On Fri, 1 Jul 2022 16:26:25 +0800, Jason Wang <jasow...@redhat.com> wrote:
>
> 在 2022/6/29 14:56, Xuan Zhuo 写道:
> > Separate the logic of split to create vring queue.
> >
> > This feature is required for subsequent virtuqueue reset vring.
> >
> > Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
> > ---
> >   drivers/virtio/virtio_ring.c | 68 ++++++++++++++++++++++--------------
> >   1 file changed, 42 insertions(+), 26 deletions(-)
> >
> > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> > index 49d61e412dc6..a9ceb9c16c54 100644
> > --- a/drivers/virtio/virtio_ring.c
> > +++ b/drivers/virtio/virtio_ring.c
> > @@ -949,28 +949,19 @@ static void vring_free_split(struct 
> > vring_virtqueue_split *vring,
> >     kfree(vring->desc_extra);
> >   }
> >
> > -static struct virtqueue *vring_create_virtqueue_split(
> > -   unsigned int index,
> > -   unsigned int num,
> > -   unsigned int vring_align,
> > -   struct virtio_device *vdev,
> > -   bool weak_barriers,
> > -   bool may_reduce_num,
> > -   bool context,
> > -   bool (*notify)(struct virtqueue *),
> > -   void (*callback)(struct virtqueue *),
> > -   const char *name)
> > +static int vring_alloc_queue_split(struct vring_virtqueue_split *vring,
> > +                              struct virtio_device *vdev,
> > +                              u32 num,
> > +                              unsigned int vring_align,
> > +                              bool may_reduce_num)
> >   {
> > -   struct virtqueue *vq;
> >     void *queue = NULL;
> >     dma_addr_t dma_addr;
> > -   size_t queue_size_in_bytes;
> > -   struct vring vring;
> >
> >     /* We assume num is a power of 2. */
> >     if (num & (num - 1)) {
> >             dev_warn(&vdev->dev, "Bad virtqueue length %u\n", num);
> > -           return NULL;
> > +           return -EINVAL;
> >     }
> >
> >     /* TODO: allocate each queue chunk individually */
> > @@ -981,11 +972,11 @@ static struct virtqueue *vring_create_virtqueue_split(
> >             if (queue)
> >                     break;
> >             if (!may_reduce_num)
> > -                   return NULL;
> > +                   return -ENOMEM;
> >     }
> >
> >     if (!num)
> > -           return NULL;
> > +           return -ENOMEM;
> >
> >     if (!queue) {
> >             /* Try to get a single page. You are my only hope! */
> > @@ -993,21 +984,46 @@ static struct virtqueue *vring_create_virtqueue_split(
> >                                       &dma_addr, GFP_KERNEL|__GFP_ZERO);
> >     }
> >     if (!queue)
> > -           return NULL;
> > +           return -ENOMEM;
> > +
> > +   vring_init(&vring->vring, num, queue, vring_align);
> >
> > -   queue_size_in_bytes = vring_size(num, vring_align);
> > -   vring_init(&vring, num, queue, vring_align);
> > +   vring->queue_dma_addr = dma_addr;
> > +   vring->queue_size_in_bytes = vring_size(num, vring_align);
> > +
> > +   return 0;
> > +}
> > +
> > +static struct virtqueue *vring_create_virtqueue_split(
> > +   unsigned int index,
> > +   unsigned int num,
> > +   unsigned int vring_align,
> > +   struct virtio_device *vdev,
> > +   bool weak_barriers,
> > +   bool may_reduce_num,
> > +   bool context,
> > +   bool (*notify)(struct virtqueue *),
> > +   void (*callback)(struct virtqueue *),
> > +   const char *name)
> > +{
> > +   struct vring_virtqueue_split vring = {};
> > +   struct virtqueue *vq;
> > +   int err;
> > +
> > +   err = vring_alloc_queue_split(&vring, vdev, num, vring_align,
> > +                                 may_reduce_num);
> > +   if (err)
> > +           return NULL;
> >
> > -   vq = __vring_new_virtqueue(index, vring, vdev, weak_barriers, context,
> > -                              notify, callback, name);
> > +   vq = __vring_new_virtqueue(index, vring.vring, vdev, weak_barriers,
> > +                              context, notify, callback, name);
> >     if (!vq) {
> > -           vring_free_queue(vdev, queue_size_in_bytes, queue,
> > -                            dma_addr);
> > +           vring_free_split(&vring, vdev);
> >             return NULL;
> >     }
> >
> > -   to_vvq(vq)->split.queue_dma_addr = dma_addr;
> > -   to_vvq(vq)->split.queue_size_in_bytes = queue_size_in_bytes;
> > +   to_vvq(vq)->split.queue_dma_addr = vring.queue_dma_addr;
>
>
> Nit: having two queue_dma_addr seems redundant (so did queue_size_in_bytes).

two?

Where is the problem I don't understand?

Thanks.

>
> Thanks
>
>
> > +   to_vvq(vq)->split.queue_size_in_bytes = vring.queue_size_in_bytes;
> >     to_vvq(vq)->we_own_ring = true;
> >
> >     return vq;
>

_______________________________________________
linux-um mailing list
linux-um@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-um

Reply via email to