Xuan Zhuo
2023-Jul-10 03:42 UTC
[PATCH vhost v11 04/10] virtio_ring: support add premapped buf
If the vq is the premapped mode, use the sg_dma_address() directly.
Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
---
drivers/virtio/virtio_ring.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 5ace4539344c..d471dee3f4f7 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -361,6 +361,11 @@ static struct device *vring_dma_dev(const struct
vring_virtqueue *vq)
static int vring_map_one_sg(const struct vring_virtqueue *vq, struct
scatterlist *sg,
enum dma_data_direction direction, dma_addr_t *addr)
{
+ if (vq->premapped) {
+ *addr = sg_dma_address(sg);
+ return 0;
+ }
+
if (!vq->use_dma_api) {
/*
* If DMA is not used, KMSAN doesn't know that the scatterlist
@@ -639,8 +644,12 @@ static inline int virtqueue_add_split(struct virtqueue
*_vq,
dma_addr_t addr = vring_map_single(
vq, desc, total_sg * sizeof(struct vring_desc),
DMA_TO_DEVICE);
- if (vring_mapping_error(vq, addr))
+ if (vring_mapping_error(vq, addr)) {
+ if (vq->premapped)
+ goto free_indirect;
+
goto unmap_release;
+ }
virtqueue_add_desc_split(_vq, vq->split.vring.desc,
head, addr,
@@ -706,6 +715,7 @@ static inline int virtqueue_add_split(struct virtqueue *_vq,
i = vring_unmap_one_split(vq, i);
}
+free_indirect:
if (indirect)
kfree(desc);
@@ -1307,8 +1317,12 @@ static int virtqueue_add_indirect_packed(struct
vring_virtqueue *vq,
addr = vring_map_single(vq, desc,
total_sg * sizeof(struct vring_packed_desc),
DMA_TO_DEVICE);
- if (vring_mapping_error(vq, addr))
+ if (vring_mapping_error(vq, addr)) {
+ if (vq->premapped)
+ goto free_desc;
+
goto unmap_release;
+ }
vq->packed.vring.desc[head].addr = cpu_to_le64(addr);
vq->packed.vring.desc[head].len = cpu_to_le32(total_sg *
@@ -1366,6 +1380,7 @@ static int virtqueue_add_indirect_packed(struct
vring_virtqueue *vq,
for (i = 0; i < err_idx; i++)
vring_unmap_desc_packed(vq, &desc[i]);
+free_desc:
kfree(desc);
END_USE(vq);
--
2.32.0.3.g01195cf9f
Jason Wang
2023-Jul-12 08:31 UTC
[PATCH vhost v11 04/10] virtio_ring: support add premapped buf
On Mon, Jul 10, 2023 at 11:42?AM Xuan Zhuo <xuanzhuo at linux.alibaba.com> wrote:> > If the vq is the premapped mode, use the sg_dma_address() directly. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > --- > drivers/virtio/virtio_ring.c | 19 +++++++++++++++++-- > 1 file changed, 17 insertions(+), 2 deletions(-) > > diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c > index 5ace4539344c..d471dee3f4f7 100644 > --- a/drivers/virtio/virtio_ring.c > +++ b/drivers/virtio/virtio_ring.c > @@ -361,6 +361,11 @@ static struct device *vring_dma_dev(const struct vring_virtqueue *vq) > static int vring_map_one_sg(const struct vring_virtqueue *vq, struct scatterlist *sg, > enum dma_data_direction direction, dma_addr_t *addr) > { > + if (vq->premapped) { > + *addr = sg_dma_address(sg); > + return 0; > + } > + > if (!vq->use_dma_api) { > /* > * If DMA is not used, KMSAN doesn't know that the scatterlist > @@ -639,8 +644,12 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, > dma_addr_t addr = vring_map_single( > vq, desc, total_sg * sizeof(struct vring_desc), > DMA_TO_DEVICE); > - if (vring_mapping_error(vq, addr)) > + if (vring_mapping_error(vq, addr)) { > + if (vq->premapped) > + goto free_indirect;Under which case could we hit this? A bug of the driver? Thanks> + > goto unmap_release; > + } > > virtqueue_add_desc_split(_vq, vq->split.vring.desc, > head, addr, > @@ -706,6 +715,7 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, > i = vring_unmap_one_split(vq, i); > } > > +free_indirect: > if (indirect) > kfree(desc); > > @@ -1307,8 +1317,12 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, > addr = vring_map_single(vq, desc, > total_sg * sizeof(struct vring_packed_desc), > DMA_TO_DEVICE); > - if (vring_mapping_error(vq, addr)) > + if (vring_mapping_error(vq, addr)) { > + if (vq->premapped) > + goto free_desc; > + > goto unmap_release; > + } > > vq->packed.vring.desc[head].addr = cpu_to_le64(addr); > vq->packed.vring.desc[head].len = cpu_to_le32(total_sg * > @@ -1366,6 +1380,7 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq, > for (i = 0; i < err_idx; i++) > vring_unmap_desc_packed(vq, &desc[i]); > > +free_desc: > kfree(desc); > > END_USE(vq); > -- > 2.32.0.3.g01195cf9f >