DMA-related logic is separated from the virtqueue_add_vring_packed() to
prepare for subsequent support for premapped.
DMA address will be saved as sg->dma_address, then
virtqueue_add_vring_packed() will use it directly.
If it is a premapped scene, the transmitted sgs should have saved DMA
address in dma_address, and in virtio core, we need to pass
virtqueue_map_sgs().
Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
---
drivers/virtio/virtio_ring.c | 59 ++++++++----------------------------
1 file changed, 12 insertions(+), 47 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 6796cbee0207..81a9c0692fec 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1350,7 +1350,7 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
struct vring_packed_desc *desc)
{
struct scatterlist *sg;
- unsigned int i, n, err_idx;
+ unsigned int i, n;
u16 head, id;
dma_addr_t addr;
@@ -1362,14 +1362,9 @@ 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)) {
- addr = vring_map_one_sg(vq, sg, n < out_sgs ?
- DMA_TO_DEVICE : DMA_FROM_DEVICE);
- if (vring_mapping_error(vq, addr))
- goto unmap_release;
-
desc[i].flags = cpu_to_le16(n < out_sgs ?
0 : VRING_DESC_F_WRITE);
- desc[i].addr = cpu_to_le64(addr);
+ desc[i].addr = cpu_to_le64(sg->dma_address);
desc[i].len = cpu_to_le32(sg->length);
i++;
}
@@ -1380,7 +1375,7 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
total_sg * sizeof(struct vring_packed_desc),
DMA_TO_DEVICE);
if (vring_mapping_error(vq, addr))
- goto unmap_release;
+ return -ENOMEM;
vq->packed.vring.desc[head].addr = cpu_to_le64(addr);
vq->packed.vring.desc[head].len = cpu_to_le32(total_sg *
@@ -1429,16 +1424,6 @@ static int virtqueue_add_indirect_packed(struct vring_virtqueue *vq,
pr_debug("Added buffer head %i to %p\n", head, vq);
return 0;
-
-unmap_release:
- err_idx = i;
-
- for (i = 0; i < err_idx; i++)
- vring_unmap_desc_packed(vq, &desc[i]);
-
- kfree(desc);
-
- return -ENOMEM;
}
static inline struct vring_packed_desc *virtqueue_get_desc_packed(struct vring_virtqueue *vq,
@@ -1498,15 +1483,14 @@ static inline int virtqueue_add_vring_packed(struct vring_virtqueue *vq,
{
struct vring_packed_desc *desc;
struct scatterlist *sg;
- unsigned int i, n, c, descs_used, err_idx;
+ unsigned int i, n, c, descs_used;
__le16 head_flags, flags;
- u16 head, id, prev, curr, avail_used_flags;
+ u16 head, id, prev, curr;
desc = vq->packed.vring.desc;
head = vq->packed.next_avail_idx;
i = head;
descs_used = total_sg;
- avail_used_flags = vq->packed.avail_used_flags;
id = vq->free_head;
BUG_ON(id == vq->packed.vring.num);
@@ -1515,11 +1499,6 @@ static inline int virtqueue_add_vring_packed(struct vring_virtqueue *vq,
c = 0;
for (n = 0; n < out_sgs + in_sgs; n++) {
for (sg = sgs[n]; sg; sg = sg_next(sg)) {
- dma_addr_t addr = vring_map_one_sg(vq, sg, n < out_sgs ?
- DMA_TO_DEVICE : DMA_FROM_DEVICE);
- if (vring_mapping_error(vq, addr))
- goto unmap_release;
-
flags = cpu_to_le16(vq->packed.avail_used_flags |
(++c == total_sg ? 0 : VRING_DESC_F_NEXT) |
(n < out_sgs ? 0 : VRING_DESC_F_WRITE));
@@ -1528,12 +1507,12 @@ static inline int virtqueue_add_vring_packed(struct vring_virtqueue *vq,
else
desc[i].flags = flags;
- desc[i].addr = cpu_to_le64(addr);
+ desc[i].addr = cpu_to_le64(sg->dma_address);
desc[i].len = cpu_to_le32(sg->length);
desc[i].id = cpu_to_le16(id);
if (unlikely(vq->use_dma_api)) {
- vq->packed.desc_extra[curr].addr = addr;
+ vq->packed.desc_extra[curr].addr = sg->dma_address;
vq->packed.desc_extra[curr].len = sg->length;
vq->packed.desc_extra[curr].flags =
le16_to_cpu(flags);
@@ -1576,25 +1555,6 @@ static inline int virtqueue_add_vring_packed(struct vring_virtqueue *vq,
pr_debug("Added buffer head %i to %p\n", head, vq);
return 0;
-
-unmap_release:
- 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)
- break;
- vring_unmap_extra_packed(vq, &vq->packed.desc_extra[curr]);
- curr = vq->packed.desc_extra[curr].next;
- i++;
- if (i >= vq->packed.vring.num)
- i = 0;
- }
-
- return -EIO;
}
static inline int virtqueue_add_packed(struct virtqueue *_vq,
@@ -1621,6 +1581,10 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
goto end;
}
+ err = virtqueue_map_sgs(vq, sgs, total_sg, out_sgs, in_sgs);
+ if (err)
+ goto err;
+
id = vq->free_head;
if (desc) {
@@ -1637,6 +1601,7 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
goto end;
err:
+ virtqueue_unmap_sgs(vq, sgs, total_sg, out_sgs, in_sgs);
kfree(desc);
end:
--
2.32.0.3.g01195cf9f
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