diff options
-rw-r--r-- | drivers/virtio/virtio_ring.c | 112 |
1 files changed, 87 insertions, 25 deletions
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 5faa876df6c6..89bfe46a8a7f 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c @@ -133,6 +133,7 @@ struct vring_virtqueue { /* Per-descriptor state. */ struct vring_desc_state_split *desc_state; + struct vring_desc_extra *desc_extra; /* DMA address and size information */ dma_addr_t queue_dma_addr; @@ -367,8 +368,8 @@ static int vring_mapping_error(const struct vring_virtqueue *vq, * Split ring specific functions - *_split(). */ -static void vring_unmap_one_split(const struct vring_virtqueue *vq, - struct vring_desc *desc) +static void vring_unmap_one_split_indirect(const struct vring_virtqueue *vq, + struct vring_desc *desc) { u16 flags; @@ -392,6 +393,35 @@ static void vring_unmap_one_split(const struct vring_virtqueue *vq, } } +static unsigned int vring_unmap_one_split(const struct vring_virtqueue *vq, + unsigned int i) +{ + struct vring_desc_extra *extra = vq->split.desc_extra; + u16 flags; + + if (!vq->use_dma_api) + goto out; + + flags = extra[i].flags; + + if (flags & VRING_DESC_F_INDIRECT) { + dma_unmap_single(vring_dma_dev(vq), + extra[i].addr, + extra[i].len, + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } else { + dma_unmap_page(vring_dma_dev(vq), + extra[i].addr, + extra[i].len, + (flags & VRING_DESC_F_WRITE) ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + } + +out: + return extra[i].next; +} + static struct vring_desc *alloc_indirect_split(struct virtqueue *_vq, unsigned int total_sg, gfp_t gfp) @@ -420,13 +450,28 @@ static inline unsigned int virtqueue_add_desc_split(struct virtqueue *vq, unsigned int i, dma_addr_t addr, unsigned int len, - u16 flags) + u16 flags, + bool indirect) { + struct vring_virtqueue *vring = to_vvq(vq); + struct vring_desc_extra *extra = vring->split.desc_extra; + u16 next; + desc[i].flags = cpu_to_virtio16(vq->vdev, flags); desc[i].addr = cpu_to_virtio64(vq->vdev, addr); desc[i].len = cpu_to_virtio32(vq->vdev, len); - return virtio16_to_cpu(vq->vdev, desc[i].next); + if (!indirect) { + next = extra[i].next; + desc[i].next = cpu_to_virtio16(vq->vdev, next); + + extra[i].addr = addr; + extra[i].len = len; + extra[i].flags = flags; + } else + next = virtio16_to_cpu(vq->vdev, desc[i].next); + + return next; } static inline int virtqueue_add_split(struct virtqueue *_vq, @@ -502,8 +547,12 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, goto unmap_release; prev = i; + /* Note that we trust indirect descriptor + * table since it use stream DMA mapping. + */ i = virtqueue_add_desc_split(_vq, desc, i, addr, sg->length, - VRING_DESC_F_NEXT); + VRING_DESC_F_NEXT, + indirect); } } for (; n < (out_sgs + in_sgs); n++) { @@ -513,14 +562,21 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, goto unmap_release; prev = i; + /* Note that we trust indirect descriptor + * table since it use stream DMA mapping. + */ i = virtqueue_add_desc_split(_vq, desc, i, addr, sg->length, VRING_DESC_F_NEXT | - VRING_DESC_F_WRITE); + VRING_DESC_F_WRITE, + indirect); } } /* Last one doesn't continue. */ desc[prev].flags &= cpu_to_virtio16(_vq->vdev, ~VRING_DESC_F_NEXT); + if (!indirect && vq->use_dma_api) + vq->split.desc_extra[prev & (vq->split.vring.num - 1)].flags = + ~VRING_DESC_F_NEXT; if (indirect) { /* Now that the indirect table is filled in, map it. */ @@ -533,7 +589,8 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, virtqueue_add_desc_split(_vq, vq->split.vring.desc, head, addr, total_sg * sizeof(struct vring_desc), - VRING_DESC_F_INDIRECT); + VRING_DESC_F_INDIRECT, + false); } /* We're using some buffers from the free list. */ @@ -541,8 +598,7 @@ static inline int virtqueue_add_split(struct virtqueue *_vq, /* Update free pointer */ if (indirect) - vq->free_head = virtio16_to_cpu(_vq->vdev, - vq->split.vring.desc[head].next); + vq->free_head = vq->split.desc_extra[head].next; else vq->free_head = i; @@ -587,8 +643,11 @@ unmap_release: for (n = 0; n < total_sg; n++) { if (i == err_idx) break; - vring_unmap_one_split(vq, &desc[i]); - i = virtio16_to_cpu(_vq->vdev, desc[i].next); + if (indirect) { + vring_unmap_one_split_indirect(vq, &desc[i]); + i = virtio16_to_cpu(_vq->vdev, desc[i].next); + } else + i = vring_unmap_one_split(vq, i); } if (indirect) @@ -642,14 +701,13 @@ static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head, i = head; while (vq->split.vring.desc[i].flags & nextflag) { - vring_unmap_one_split(vq, &vq->split.vring.desc[i]); - i = virtio16_to_cpu(vq->vq.vdev, vq->split.vring.desc[i].next); + vring_unmap_one_split(vq, i); + i = vq->split.desc_extra[i].next; vq->vq.num_free++; } - vring_unmap_one_split(vq, &vq->split.vring.desc[i]); - vq->split.vring.desc[i].next = cpu_to_virtio16(vq->vq.vdev, - vq->free_head); + vring_unmap_one_split(vq, i); + vq->split.desc_extra[i].next = vq->free_head; vq->free_head = head; /* Plus final descriptor */ @@ -664,15 +722,14 @@ static void detach_buf_split(struct vring_virtqueue *vq, unsigned int head, if (!indir_desc) return; - len = virtio32_to_cpu(vq->vq.vdev, - vq->split.vring.desc[head].len); + len = vq->split.desc_extra[head].len; - BUG_ON(!(vq->split.vring.desc[head].flags & - cpu_to_virtio16(vq->vq.vdev, VRING_DESC_F_INDIRECT))); + BUG_ON(!(vq->split.desc_extra[head].flags & + VRING_DESC_F_INDIRECT)); BUG_ON(len == 0 || len % sizeof(struct vring_desc)); for (j = 0; j < len / sizeof(struct vring_desc); j++) - vring_unmap_one_split(vq, &indir_desc[j]); + vring_unmap_one_split_indirect(vq, &indir_desc[j]); kfree(indir_desc); vq->split.desc_state[head].indir_desc = NULL; @@ -2108,7 +2165,6 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, void (*callback)(struct virtqueue *), const char *name) { - unsigned int i; struct vring_virtqueue *vq; if (virtio_has_feature(vdev, VIRTIO_F_RING_PACKED)) @@ -2164,16 +2220,20 @@ struct virtqueue *__vring_new_virtqueue(unsigned int index, if (!vq->split.desc_state) goto err_state; + vq->split.desc_extra = vring_alloc_desc_extra(vq, vring.num); + if (!vq->split.desc_extra) + goto err_extra; + /* Put everything in free lists. */ vq->free_head = 0; - for (i = 0; i < vring.num-1; i++) - vq->split.vring.desc[i].next = cpu_to_virtio16(vdev, i + 1); memset(vq->split.desc_state, 0, vring.num * sizeof(struct vring_desc_state_split)); list_add_tail(&vq->vq.list, &vdev->vqs); return &vq->vq; +err_extra: + kfree(vq->split.desc_state); err_state: kfree(vq); return NULL; @@ -2257,8 +2317,10 @@ void vring_del_virtqueue(struct virtqueue *_vq) vq->split.queue_dma_addr); } } - if (!vq->packed_ring) + if (!vq->packed_ring) { kfree(vq->split.desc_state); + kfree(vq->split.desc_extra); + } list_del(&_vq->list); kfree(vq); } |