From d7344a2f71e38eb04fc16e3fef4f0580f42cbbd5 Mon Sep 17 00:00:00 2001 From: Xuan Zhuo Date: Thu, 10 Aug 2023 20:30:49 +0800 Subject: virtio_ring: support add premapped buf If the vq is the premapped mode, use the sg_dma_address() directly. Signed-off-by: Xuan Zhuo Message-Id: <20230810123057.43407-5-xuanzhuo@linux.alibaba.com> Signed-off-by: Michael S. Tsirkin --- 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 8e81b01e073505..f9f772e85a38b9 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 @@ unmap_release: 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 @@ unmap_release: for (i = 0; i < err_idx; i++) vring_unmap_desc_packed(vq, &desc[i]); +free_desc: kfree(desc); END_USE(vq); -- cgit 1.2.3-korg