On Fri, Jun 2, 2023 at 5:22 PM Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx> wrote:
>
> If the vq is the premapped mode, use the sg_dma_address() directly.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
> ---
> drivers/virtio/virtio_ring.c | 36 ++++++++++++++++++++++++++----------
> 1 file changed, 26 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
> index 18212c3e056b..dc109fbc05a5 100644
> --- a/drivers/virtio/virtio_ring.c
> +++ b/drivers/virtio/virtio_ring.c
> @@ -1299,9 +1299,13 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
>
> for (n = 0; n < out_sgs + in_sgs; n++) {
> for (sg = sgs[n]; sg; sg = sg_next(sg)) {
> - if (vring_map_one_sg(vq, sg, n < out_sgs ?
> - DMA_TO_DEVICE : DMA_FROM_DEVICE, &addr))
> - goto unmap_release;
> + if (vq->premapped) {
> + addr = sg_dma_address(sg);
> + } else {
> + if (vring_map_one_sg(vq, sg, n < out_sgs ?
> + DMA_TO_DEVICE : DMA_FROM_DEVICE, &addr))
> + goto unmap_release;
> + }
>
> desc[i].flags = cpu_to_le16(n < out_sgs ?
> 0 : VRING_DESC_F_WRITE);
> @@ -1369,10 +1373,12 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
> return 0;
>
> unmap_release:
> - err_idx = i;
> + if (!vq->premapped) {
> + err_idx = i;
>
> - for (i = 0; i < err_idx; i++)
> - vring_unmap_desc_packed(vq, &desc[i]);
> + for (i = 0; i < err_idx; i++)
> + vring_unmap_desc_packed(vq, &desc[i]);
> + }
>
> kfree(desc);
>
> @@ -1447,9 +1453,13 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
> for (sg = sgs[n]; sg; sg = sg_next(sg)) {
> dma_addr_t addr;
>
> - if (vring_map_one_sg(vq, sg, n < out_sgs ?
> - DMA_TO_DEVICE : DMA_FROM_DEVICE, &addr))
> - goto unmap_release;
> + if (vq->premapped) {
> + addr = sg_dma_address(sg);
> + } else {
> + if (vring_map_one_sg(vq, sg, n < out_sgs ?
> + DMA_TO_DEVICE : DMA_FROM_DEVICE, &addr))
> + goto unmap_release;
> + }
>
> flags = cpu_to_le16(vq->packed.avail_used_flags |
> (++c == total_sg ? 0 : VRING_DESC_F_NEXT) |
> @@ -1512,11 +1522,17 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
> return 0;
>
> unmap_release:
> + vq->packed.avail_used_flags = avail_used_flags;
> +
> + if (vq->premapped) {
Similar to the split path, I think we can't hit vq->premapped here.
Thanks
> + END_USE(vq);
> + return -EIO;
> + }
> +
> err_idx = i;
> i = head;
> curr = vq->free_head;
>
> - vq->packed.avail_used_flags = avail_used_flags;
>
> for (n = 0; n < total_sg; n++) {
> if (i == err_idx)
> --
> 2.32.0.3.g01195cf9f
>
