Function virtqueue_alloc

dpdk/drivers/net/virtio/virtqueue.c:421–509

}

struct virtqueue *
virtqueue_alloc(struct virtio_hw *hw, uint16_t index, uint16_t num, int type,
		int node, const char *name)
{
	struct virtqueue *vq;
	const struct rte_memzone *mz;
	unsigned int size;

	size = sizeof(*vq) + num * sizeof(struct vq_desc_extra);
	size = RTE_ALIGN_CEIL(size, RTE_CACHE_LINE_SIZE);

	vq = rte_zmalloc_socket(name, size, RTE_CACHE_LINE_SIZE, node);
	if (vq == NULL) {
		PMD_INIT_LOG(ERR, "can not allocate vq");
		return NULL;
	}

	vq->hw = hw;
	vq->vq_queue_index = index;
	vq->vq_nentries = num;
	if (virtio_with_packed_queue(hw)) {
		vq->vq_packed.used_wrap_counter = 1;
		vq->vq_packed.cached_flags = VRING_PACKED_DESC_F_AVAIL;
		vq->vq_packed.event_flags_shadow = 0;
		if (type == VTNET_RQ)
			vq->vq_packed.cached_flags |= VRING_DESC_F_WRITE;
	}

	/*
	 * Reserve a memzone for vring elements
	 */
	size = vring_size(hw, num, VIRTIO_VRING_ALIGN);
	vq->vq_ring_size = RTE_ALIGN_CEIL(size, VIRTIO_VRING_ALIGN);
	PMD_INIT_LOG(DEBUG, "vring_size: %d, rounded_vring_size: %d", size, vq->vq_ring_size);

	mz = rte_memzone_reserve_aligned(name, vq->vq_ring_size, node,
			RTE_MEMZONE_IOVA_CONTIG, VIRTIO_VRING_ALIGN);
	if (mz == NULL) {
		if (rte_errno == EEXIST)
			mz = rte_memzone_lookup(name);
		if (mz == NULL)
			goto free_vq;
	}

	memset(mz->addr, 0, mz->len);
	vq->mz = mz;
	vq->vq_ring_virt_mem = mz->addr;

	if (hw->use_va) {
		vq->vq_ring_mem = (uintptr_t)mz->addr;
		vq->mbuf_addr_offset = offsetof(struct rte_mbuf, buf_addr);
		vq->mbuf_addr_mask = UINTPTR_MAX;
	} else {
		vq->vq_ring_mem = mz->iova;
		vq->mbuf_addr_offset = offsetof(struct rte_mbuf, buf_iova);
		vq->mbuf_addr_mask = UINT64_MAX;
	}