diff mbox series

[vhost,v10,04/10] virtio_ring: packed: support add premapped buf

Message ID 20230602092206.50108-5-xuanzhuo@linux.alibaba.com (mailing list archive)
State Not Applicable
Headers show
Series virtio core prepares for AF_XDP | expand

Checks

Context Check Description
netdev/tree_selection success Guessing tree name failed - patch did not apply

Commit Message

Xuan Zhuo June 2, 2023, 9:22 a.m. UTC 
If the vq is the premapped mode, use the sg_dma_address() directly.

Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
 drivers/virtio/virtio_ring.c | 36 ++++++++++++++++++++++++++----------
 1 file changed, 26 insertions(+), 10 deletions(-)

Comments

Jason Wang June 27, 2023, 8:03 a.m. UTC | #1 
On Fri, Jun 2, 2023 at 5:22 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
>
> If the vq is the premapped mode, use the sg_dma_address() directly.
>
> Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> ---
>  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
>
Xuan Zhuo June 27, 2023, 9:05 a.m. UTC | #2 
On Tue, 27 Jun 2023 16:03:29 +0800, Jason Wang <jasowang@redhat.com> wrote:
> On Fri, Jun 2, 2023 at 5:22 PM Xuan Zhuo <xuanzhuo@linux.alibaba.com> wrote:
> >
> > If the vq is the premapped mode, use the sg_dma_address() directly.
> >
> > Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
> > ---
> >  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.


YES, similar to the above reply, we can have a better way.

But, we can hit vq->premapped, when we fail doing dma for the indirect desc
array.

Thanks.




>
> 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
> >
>
diff mbox series

Patch

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) {
+		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)