vhost: provide helpers for virtio ring relay

[dpdk.git] / lib / librte_vhost / vdpa.c

diff --git a/lib/librte_vhost/vdpa.c b/lib/librte_vhost/vdpa.c
index e7d849e..240a1fe 100644 (file)
--- a/lib/librte_vhost/vdpa.c
+++ b/lib/librte_vhost/vdpa.c
@@ -122,3 +122,197 @@ rte_vdpa_get_device_num(void)
 {
        return vdpa_device_num;
 }
+
+static bool
+invalid_desc_check(struct virtio_net *dev, struct vhost_virtqueue *vq,
+               uint64_t desc_iova, uint64_t desc_len, uint8_t perm)
+{
+       uint64_t desc_addr, desc_chunck_len;
+
+       while (desc_len) {
+               desc_chunck_len = desc_len;
+               desc_addr = vhost_iova_to_vva(dev, vq,
+                               desc_iova,
+                               &desc_chunck_len,
+                               perm);
+
+               if (!desc_addr)
+                       return true;
+
+               desc_len -= desc_chunck_len;
+               desc_iova += desc_chunck_len;
+       }
+
+       return false;
+}
+
+int __rte_experimental
+rte_vdpa_relay_vring_avail(int vid, uint16_t qid, void *vring_m)
+{
+       struct virtio_net *dev = get_device(vid);
+       uint16_t idx, idx_m, desc_id;
+       struct vring_desc desc;
+       struct vhost_virtqueue *vq;
+       struct vring_desc *desc_ring;
+       struct vring_desc *idesc = NULL;
+       struct vring *s_vring;
+       uint64_t dlen;
+       int ret;
+       uint8_t perm;
+
+       if (!dev || !vring_m)
+               return -1;
+
+       if (qid >= dev->nr_vring)
+               return -1;
+
+       if (vq_is_packed(dev))
+               return -1;
+
+       s_vring = (struct vring *)vring_m;
+       vq = dev->virtqueue[qid];
+       idx = vq->avail->idx;
+       idx_m = s_vring->avail->idx;
+       ret = (uint16_t)(idx - idx_m);
+
+       while (idx_m != idx) {
+               /* avail entry copy */
+               desc_id = vq->avail->ring[idx_m & (vq->size - 1)];
+               s_vring->avail->ring[idx_m & (vq->size - 1)] = desc_id;
+               desc_ring = vq->desc;
+
+               if (vq->desc[desc_id].flags & VRING_DESC_F_INDIRECT) {
+                       dlen = vq->desc[desc_id].len;
+                       desc_ring = (struct vring_desc *)(uintptr_t)
+                               vhost_iova_to_vva(dev, vq,
+                                               vq->desc[desc_id].addr, &dlen,
+                                               VHOST_ACCESS_RO);
+                       if (unlikely(!desc_ring))
+                               return -1;
+
+                       if (unlikely(dlen < vq->desc[idx].len)) {
+                               idesc = alloc_copy_ind_table(dev, vq,
+                                               vq->desc[idx].addr,
+                                               vq->desc[idx].len);
+                               if (unlikely(!idesc))
+                                       return -1;
+
+                               desc_ring = idesc;
+                       }
+
+                       desc_id = 0;
+               }
+
+               /* check if the buf addr is within the guest memory */
+               do {
+                       desc = desc_ring[desc_id];
+                       perm = desc.flags & VRING_DESC_F_WRITE ?
+                               VHOST_ACCESS_WO : VHOST_ACCESS_RO;
+                       if (invalid_desc_check(dev, vq, desc.addr, desc.len,
+                                               perm)) {
+                               if (unlikely(idesc))
+                                       free_ind_table(idesc);
+                               return -1;
+                       }
+                       desc_id = desc.next;
+               } while (desc.flags & VRING_DESC_F_NEXT);
+
+               if (unlikely(idesc)) {
+                       free_ind_table(idesc);
+                       idesc = NULL;
+               }
+
+               idx_m++;
+       }
+
+       rte_smp_wmb();
+       s_vring->avail->idx = idx;
+
+       if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))
+               vhost_avail_event(vq) = idx;
+
+       return ret;
+}
+
+int __rte_experimental
+rte_vdpa_relay_vring_used(int vid, uint16_t qid, void *vring_m)
+{
+       struct virtio_net *dev = get_device(vid);
+       uint16_t idx, idx_m, desc_id;
+       struct vhost_virtqueue *vq;
+       struct vring_desc desc;
+       struct vring_desc *desc_ring;
+       struct vring_desc *idesc = NULL;
+       struct vring *s_vring;
+       uint64_t dlen;
+       int ret;
+
+       if (!dev || !vring_m)
+               return -1;
+
+       if (qid >= dev->nr_vring)
+               return -1;
+
+       if (vq_is_packed(dev))
+               return -1;
+
+       s_vring = (struct vring *)vring_m;
+       vq = dev->virtqueue[qid];
+       idx = vq->used->idx;
+       idx_m = s_vring->used->idx;
+       ret = (uint16_t)(idx_m - idx);
+
+       while (idx != idx_m) {
+               /* copy used entry, used ring logging is not covered here */
+               vq->used->ring[idx & (vq->size - 1)] =
+                       s_vring->used->ring[idx & (vq->size - 1)];
+
+               desc_id = vq->used->ring[idx & (vq->size - 1)].id;
+               desc_ring = vq->desc;
+
+               if (vq->desc[desc_id].flags & VRING_DESC_F_INDIRECT) {
+                       dlen = vq->desc[desc_id].len;
+                       desc_ring = (struct vring_desc *)(uintptr_t)
+                               vhost_iova_to_vva(dev, vq,
+                                               vq->desc[desc_id].addr, &dlen,
+                                               VHOST_ACCESS_RO);
+                       if (unlikely(!desc_ring))
+                               return -1;
+
+                       if (unlikely(dlen < vq->desc[idx].len)) {
+                               idesc = alloc_copy_ind_table(dev, vq,
+                                               vq->desc[idx].addr,
+                                               vq->desc[idx].len);
+                               if (unlikely(!idesc))
+                                       return -1;
+
+                               desc_ring = idesc;
+                       }
+
+                       desc_id = 0;
+               }
+
+               /* dirty page logging for DMA writeable buffer */
+               do {
+                       desc = desc_ring[desc_id];
+                       if (desc.flags & VRING_DESC_F_WRITE)
+                               vhost_log_write(dev, desc.addr, desc.len);
+                       desc_id = desc.next;
+               } while (desc.flags & VRING_DESC_F_NEXT);
+
+               if (unlikely(idesc)) {
+                       free_ind_table(idesc);
+                       idesc = NULL;
+               }
+
+               idx++;
+       }
+
+       rte_smp_wmb();
+       vq->used->idx = idx_m;
+
+       if (dev->features & (1ULL << VIRTIO_RING_F_EVENT_IDX))
+               vring_used_event(s_vring) = idx_m;
+
+       return ret;
+}