---
drivers/virtio/virtio_ring.c | 79 ++++++++++++++++++++++++++----------
1 file changed, 57 insertions(+), 22 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index d32c0bf6016f..b8c7697e925d 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1011,7 +1011,8 @@ static struct virtqueue *vring_create_virtqueue_split(
*/
static void vring_unmap_extra_packed(const struct vring_virtqueue *vq,
- struct vring_desc_extra *extra)
+ struct vring_desc_extra *extra,
+ bool predma)
{
u16 flags;
@@ -1026,6 +1027,9 @@ static void vring_unmap_extra_packed(const struct vring_virtqueue *vq,
(flags & VRING_DESC_F_WRITE) ?
DMA_FROM_DEVICE : DMA_TO_DEVICE);
} else {
+ if (predma)
+ return;
+
dma_unmap_page(vring_dma_dev(vq),
extra->addr, extra->len,
(flags & VRING_DESC_F_WRITE) ?
@@ -1073,7 +1077,8 @@ static int virtqueue_add_indirect_packed(struct
vring_virtqueue *vq,
unsigned int out_sgs,
unsigned int in_sgs,
void *data,
- gfp_t gfp)
+ gfp_t gfp,
+ bool predma)
{
struct vring_packed_desc *desc;
struct scatterlist *sg;
@@ -1099,10 +1104,15 @@ 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;
+ if (predma) {
+ addr = sg_dma_address(sg);
+
+ } else {
+ 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);
@@ -1132,6 +1142,9 @@ static int virtqueue_add_indirect_packed(struct
vring_virtqueue *vq,
vq->packed.avail_used_flags;
}
+ if (predma)
+ vq->packed.desc_extra[id].flags |= VIRTIO_DESC_F_PREDMA;
+
/*
* A driver MUST NOT make the first descriptor in the list
* available before all subsequent descriptors comprising
@@ -1170,10 +1183,11 @@ static int virtqueue_add_indirect_packed(struct
vring_virtqueue *vq,
return 0;
unmap_release:
- err_idx = i;
-
- for (i = 0; i < err_idx; i++)
- vring_unmap_desc_packed(vq, &desc[i]);
+ if (!predma) {
+ err_idx = i;
+ for (i = 0; i < err_idx; i++)
+ vring_unmap_desc_packed(vq, &desc[i]);
+ }
kfree(desc);
@@ -1188,7 +1202,8 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
unsigned int in_sgs,
void *data,
void *ctx,
- gfp_t gfp)
+ gfp_t gfp,
+ bool predma)
{
struct vring_virtqueue *vq = to_vvq(_vq);
struct vring_packed_desc *desc;
@@ -1214,7 +1229,7 @@ static inline int virtqueue_add_packed(struct virtqueue
*_vq,
if (virtqueue_use_indirect(_vq, total_sg)) {
err = virtqueue_add_indirect_packed(vq, sgs, total_sg, out_sgs,
- in_sgs, data, gfp);
+ in_sgs, data, gfp, predma);
if (err != -ENOMEM) {
END_USE(vq);
return err;
@@ -1246,10 +1261,17 @@ static inline int virtqueue_add_packed(struct 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;
+ dma_addr_t addr;
+
+ if (predma) {
+ addr = sg_dma_address(sg);
+
+ } else {
+ 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) |
@@ -1297,6 +1319,9 @@ static inline int virtqueue_add_packed(struct virtqueue
*_vq,
vq->packed.desc_state[id].indir_desc = ctx;
vq->packed.desc_state[id].last = prev;
+ if (predma)
+ vq->packed.desc_extra[id].flags |= VIRTIO_DESC_F_PREDMA;
+
/*
* A driver MUST NOT make the first descriptor in the list
* available before all subsequent descriptors comprising
@@ -1312,22 +1337,27 @@ static inline int virtqueue_add_packed(struct virtqueue
*_vq,
return 0;
unmap_release:
+ vq->packed.avail_used_flags = avail_used_flags;
+
+ if (predma)
+ goto skip_unmap;
+
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]);
+ vring_unmap_extra_packed(vq, &vq->packed.desc_extra[curr],
false);
curr = vq->packed.desc_extra[curr].next;
i++;
if (i >= vq->packed.vring.num)
i = 0;
}
+skip_unmap:
+
END_USE(vq);
return -EIO;
}
@@ -1387,9 +1417,13 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
struct vring_desc_state_packed *state = NULL;
struct vring_packed_desc *desc;
unsigned int i, curr;
+ bool predma = false;
state = &vq->packed.desc_state[id];
+ if (vq->packed.desc_extra[state->last].flags & VIRTIO_DESC_F_PREDMA)
+ predma = true;
+
/* Clear data ptr. */
state->data = NULL;
@@ -1401,7 +1435,8 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
curr = id;
for (i = 0; i < state->num; i++) {
vring_unmap_extra_packed(vq,
- &vq->packed.desc_extra[curr]);
+ &vq->packed.desc_extra[curr],
+ predma);
curr = vq->packed.desc_extra[curr].next;
}
}
@@ -1414,7 +1449,7 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
if (!desc)
return;
- if (vq->use_dma_api) {
+ if (vq->use_dma_api && !predma) {
len = vq->packed.desc_extra[id].len;
for (i = 0; i < len / sizeof(struct vring_packed_desc);
i++)
@@ -1820,7 +1855,7 @@ static inline int virtqueue_add(struct virtqueue *_vq,
struct vring_virtqueue *vq = to_vvq(_vq);
return vq->packed_ring ? virtqueue_add_packed(_vq, sgs, total_sg,
- out_sgs, in_sgs, data, ctx, gfp) :
+ out_sgs, in_sgs, data, ctx, gfp,
predma) :
virtqueue_add_split(_vq, sgs, total_sg,
out_sgs, in_sgs, data, ctx, gfp,
predma);
}
