virtqueue_add_packed() only supports virtual addresses, dma is completed
in virtqueue_add_packed().
In some scenarios (such as the AF_XDP scenario), the memory is allocated
and DMA is completed in advance, so it is necessary for us to support
passing the DMA address to virtio core.
Signed-off-by: Xuan Zhuo <xuanz...@linux.alibaba.com>
---
drivers/virtio/virtio_ring.c | 36 ++++++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 10 deletions(-)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 81a9c0692fec..5e98f828236d 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -78,6 +78,7 @@ struct vring_desc_state_packed {
struct vring_packed_desc *indir_desc; /* Indirect descriptor, if any. */
u16 num; /* Descriptor list length. */
u16 last; /* The last desc state in a list. */
+ bool dma_map; /* Addr is mapped by virtio core or
not. */
};
struct vring_desc_extra {
@@ -1286,7 +1287,8 @@ static inline u16 packed_last_used(u16 last_used_idx)
}
static void vring_unmap_extra_packed(const struct vring_virtqueue *vq,
- struct vring_desc_extra *extra)
+ struct vring_desc_extra *extra,
+ bool dma_map)
{
u16 flags;
@@ -1301,6 +1303,9 @@ static void vring_unmap_extra_packed(const struct
vring_virtqueue *vq,
(flags & VRING_DESC_F_WRITE) ?
DMA_FROM_DEVICE : DMA_TO_DEVICE);
} else {
+ if (!dma_map)
+ return;
+
dma_unmap_page(vring_dma_dev(vq),
extra->addr, extra->len,
(flags & VRING_DESC_F_WRITE) ?
@@ -1564,6 +1569,7 @@ static inline int virtqueue_add_packed(struct virtqueue
*_vq,
unsigned int in_sgs,
void *data,
void *ctx,
+ bool dma_map,
gfp_t gfp)
{
@@ -1581,9 +1587,11 @@ 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;
+ if (dma_map) {
+ err = virtqueue_map_sgs(vq, sgs, total_sg, out_sgs, in_sgs);
+ if (err)
+ goto err;
+ }
id = vq->free_head;
@@ -1597,11 +1605,14 @@ static inline int virtqueue_add_packed(struct virtqueue
*_vq,
}
vq->packed.desc_state[id].data = data;
+ vq->packed.desc_state[id].dma_map = dma_map;
goto end;
err:
- virtqueue_unmap_sgs(vq, sgs, total_sg, out_sgs, in_sgs);
+ if (dma_map)
+ virtqueue_unmap_sgs(vq, sgs, total_sg, out_sgs, in_sgs);
+
kfree(desc);
end:
@@ -1664,8 +1675,10 @@ 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 dma_map;
state = &vq->packed.desc_state[id];
+ dma_map = state->dma_map;
/* Clear data ptr. */
state->data = NULL;
@@ -1678,7 +1691,8 @@ 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],
+ dma_map);
curr = vq->packed.desc_extra[curr].next;
}
}
@@ -1691,7 +1705,7 @@ static void detach_buf_packed(struct vring_virtqueue *vq,
if (!desc)
return;
- if (vq->use_dma_api) {
+ if (vq->use_dma_api && dma_map) {
len = vq->packed.desc_extra[id].len;
for (i = 0; i < len / sizeof(struct vring_packed_desc);
i++)
@@ -2218,7 +2232,7 @@ 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, true, gfp) :
virtqueue_add_split(_vq, sgs, total_sg,
out_sgs, in_sgs, data, ctx, true, gfp);
}
@@ -2234,8 +2248,10 @@ static inline int virtqueue_add_premapped(struct
virtqueue *_vq,
{
struct vring_virtqueue *vq = to_vvq(_vq);
- return virtqueue_add_split(_vq, sgs, total_sg, out_sgs, in_sgs, data,
- ctx, false, gfp);
+ return vq->packed_ring ? virtqueue_add_packed(_vq, sgs, total_sg,
+ out_sgs, in_sgs, data,
ctx, false, gfp) :
+ virtqueue_add_split(_vq, sgs, total_sg, out_sgs,
+ in_sgs, data, ctx, false,
gfp);
}
/**
--
2.32.0.3.g01195cf9f
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