diff options
Diffstat (limited to 'lib/librte_vhost/virtio_net.c')
| -rw-r--r-- | lib/librte_vhost/virtio_net.c | 1182 |
1 files changed, 1182 insertions, 0 deletions
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c new file mode 100644 index 00000000..595f67c4 --- /dev/null +++ b/lib/librte_vhost/virtio_net.c @@ -0,0 +1,1182 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2010-2016 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <stdint.h> +#include <stdbool.h> +#include <linux/virtio_net.h> + +#include <rte_mbuf.h> +#include <rte_memcpy.h> +#include <rte_ether.h> +#include <rte_ip.h> +#include <rte_virtio_net.h> +#include <rte_tcp.h> +#include <rte_udp.h> +#include <rte_sctp.h> +#include <rte_arp.h> + +#include "vhost.h" + +#define MAX_PKT_BURST 32 +#define VHOST_LOG_PAGE 4096 + +static inline void __attribute__((always_inline)) +vhost_log_page(uint8_t *log_base, uint64_t page) +{ + log_base[page / 8] |= 1 << (page % 8); +} + +static inline void __attribute__((always_inline)) +vhost_log_write(struct virtio_net *dev, uint64_t addr, uint64_t len) +{ + uint64_t page; + + if (likely(((dev->features & (1ULL << VHOST_F_LOG_ALL)) == 0) || + !dev->log_base || !len)) + return; + + if (unlikely(dev->log_size <= ((addr + len - 1) / VHOST_LOG_PAGE / 8))) + return; + + /* To make sure guest memory updates are committed before logging */ + rte_smp_wmb(); + + page = addr / VHOST_LOG_PAGE; + while (page * VHOST_LOG_PAGE < addr + len) { + vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page); + page += 1; + } +} + +static inline void __attribute__((always_inline)) +vhost_log_used_vring(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint64_t offset, uint64_t len) +{ + vhost_log_write(dev, vq->log_guest_addr + offset, len); +} + +static bool +is_valid_virt_queue_idx(uint32_t idx, int is_tx, uint32_t qp_nb) +{ + return (is_tx ^ (idx & 1)) == 0 && idx < qp_nb * VIRTIO_QNUM; +} + +static inline void __attribute__((always_inline)) +do_flush_shadow_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint16_t to, uint16_t from, uint16_t size) +{ + rte_memcpy(&vq->used->ring[to], + &vq->shadow_used_ring[from], + size * sizeof(struct vring_used_elem)); + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, ring[to]), + size * sizeof(struct vring_used_elem)); +} + +static inline void __attribute__((always_inline)) +flush_shadow_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq) +{ + uint16_t used_idx = vq->last_used_idx & (vq->size - 1); + + if (used_idx + vq->shadow_used_idx <= vq->size) { + do_flush_shadow_used_ring(dev, vq, used_idx, 0, + vq->shadow_used_idx); + } else { + uint16_t size; + + /* update used ring interval [used_idx, vq->size] */ + size = vq->size - used_idx; + do_flush_shadow_used_ring(dev, vq, used_idx, 0, size); + + /* update the left half used ring interval [0, left_size] */ + do_flush_shadow_used_ring(dev, vq, 0, size, + vq->shadow_used_idx - size); + } + vq->last_used_idx += vq->shadow_used_idx; + + rte_smp_wmb(); + + *(volatile uint16_t *)&vq->used->idx += vq->shadow_used_idx; + vhost_log_used_vring(dev, vq, offsetof(struct vring_used, idx), + sizeof(vq->used->idx)); +} + +static inline void __attribute__((always_inline)) +update_shadow_used_ring(struct vhost_virtqueue *vq, + uint16_t desc_idx, uint16_t len) +{ + uint16_t i = vq->shadow_used_idx++; + + vq->shadow_used_ring[i].id = desc_idx; + vq->shadow_used_ring[i].len = len; +} + +static void +virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr) +{ + if (m_buf->ol_flags & PKT_TX_L4_MASK) { + net_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; + net_hdr->csum_start = m_buf->l2_len + m_buf->l3_len; + + switch (m_buf->ol_flags & PKT_TX_L4_MASK) { + case PKT_TX_TCP_CKSUM: + net_hdr->csum_offset = (offsetof(struct tcp_hdr, + cksum)); + break; + case PKT_TX_UDP_CKSUM: + net_hdr->csum_offset = (offsetof(struct udp_hdr, + dgram_cksum)); + break; + case PKT_TX_SCTP_CKSUM: + net_hdr->csum_offset = (offsetof(struct sctp_hdr, + cksum)); + break; + } + } + + if (m_buf->ol_flags & PKT_TX_TCP_SEG) { + if (m_buf->ol_flags & PKT_TX_IPV4) + net_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; + else + net_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; + net_hdr->gso_size = m_buf->tso_segsz; + net_hdr->hdr_len = m_buf->l2_len + m_buf->l3_len + + m_buf->l4_len; + } +} + +static inline void +copy_virtio_net_hdr(struct virtio_net *dev, uint64_t desc_addr, + struct virtio_net_hdr_mrg_rxbuf hdr) +{ + if (dev->vhost_hlen == sizeof(struct virtio_net_hdr_mrg_rxbuf)) + *(struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)desc_addr = hdr; + else + *(struct virtio_net_hdr *)(uintptr_t)desc_addr = hdr.hdr; +} + +static inline int __attribute__((always_inline)) +copy_mbuf_to_desc(struct virtio_net *dev, struct vring_desc *descs, + struct rte_mbuf *m, uint16_t desc_idx, uint32_t size) +{ + uint32_t desc_avail, desc_offset; + uint32_t mbuf_avail, mbuf_offset; + uint32_t cpy_len; + struct vring_desc *desc; + uint64_t desc_addr; + struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0}; + + desc = &descs[desc_idx]; + desc_addr = gpa_to_vva(dev, desc->addr); + /* + * Checking of 'desc_addr' placed outside of 'unlikely' macro to avoid + * performance issue with some versions of gcc (4.8.4 and 5.3.0) which + * otherwise stores offset on the stack instead of in a register. + */ + if (unlikely(desc->len < dev->vhost_hlen) || !desc_addr) + return -1; + + rte_prefetch0((void *)(uintptr_t)desc_addr); + + virtio_enqueue_offload(m, &virtio_hdr.hdr); + copy_virtio_net_hdr(dev, desc_addr, virtio_hdr); + vhost_log_write(dev, desc->addr, dev->vhost_hlen); + PRINT_PACKET(dev, (uintptr_t)desc_addr, dev->vhost_hlen, 0); + + desc_offset = dev->vhost_hlen; + desc_avail = desc->len - dev->vhost_hlen; + + mbuf_avail = rte_pktmbuf_data_len(m); + mbuf_offset = 0; + while (mbuf_avail != 0 || m->next != NULL) { + /* done with current mbuf, fetch next */ + if (mbuf_avail == 0) { + m = m->next; + + mbuf_offset = 0; + mbuf_avail = rte_pktmbuf_data_len(m); + } + + /* done with current desc buf, fetch next */ + if (desc_avail == 0) { + if ((desc->flags & VRING_DESC_F_NEXT) == 0) { + /* Room in vring buffer is not enough */ + return -1; + } + if (unlikely(desc->next >= size)) + return -1; + + desc = &descs[desc->next]; + desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + + desc_offset = 0; + desc_avail = desc->len; + } + + cpy_len = RTE_MIN(desc_avail, mbuf_avail); + rte_memcpy((void *)((uintptr_t)(desc_addr + desc_offset)), + rte_pktmbuf_mtod_offset(m, void *, mbuf_offset), + cpy_len); + vhost_log_write(dev, desc->addr + desc_offset, cpy_len); + PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset), + cpy_len, 0); + + mbuf_avail -= cpy_len; + mbuf_offset += cpy_len; + desc_avail -= cpy_len; + desc_offset += cpy_len; + } + + return 0; +} + +/** + * This function adds buffers to the virtio devices RX virtqueue. Buffers can + * be received from the physical port or from another virtio device. A packet + * count is returned to indicate the number of packets that are succesfully + * added to the RX queue. This function works when the mbuf is scattered, but + * it doesn't support the mergeable feature. + */ +static inline uint32_t __attribute__((always_inline)) +virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id, + struct rte_mbuf **pkts, uint32_t count) +{ + struct vhost_virtqueue *vq; + uint16_t avail_idx, free_entries, start_idx; + uint16_t desc_indexes[MAX_PKT_BURST]; + struct vring_desc *descs; + uint16_t used_idx; + uint32_t i, sz; + + LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__); + if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->virt_qp_nb))) { + RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n", + dev->vid, __func__, queue_id); + return 0; + } + + vq = dev->virtqueue[queue_id]; + if (unlikely(vq->enabled == 0)) + return 0; + + avail_idx = *((volatile uint16_t *)&vq->avail->idx); + start_idx = vq->last_used_idx; + free_entries = avail_idx - start_idx; + count = RTE_MIN(count, free_entries); + count = RTE_MIN(count, (uint32_t)MAX_PKT_BURST); + if (count == 0) + return 0; + + LOG_DEBUG(VHOST_DATA, "(%d) start_idx %d | end_idx %d\n", + dev->vid, start_idx, start_idx + count); + + /* Retrieve all of the desc indexes first to avoid caching issues. */ + rte_prefetch0(&vq->avail->ring[start_idx & (vq->size - 1)]); + for (i = 0; i < count; i++) { + used_idx = (start_idx + i) & (vq->size - 1); + desc_indexes[i] = vq->avail->ring[used_idx]; + vq->used->ring[used_idx].id = desc_indexes[i]; + vq->used->ring[used_idx].len = pkts[i]->pkt_len + + dev->vhost_hlen; + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, ring[used_idx]), + sizeof(vq->used->ring[used_idx])); + } + + rte_prefetch0(&vq->desc[desc_indexes[0]]); + for (i = 0; i < count; i++) { + uint16_t desc_idx = desc_indexes[i]; + int err; + + if (vq->desc[desc_idx].flags & VRING_DESC_F_INDIRECT) { + descs = (struct vring_desc *)(uintptr_t)gpa_to_vva(dev, + vq->desc[desc_idx].addr); + if (unlikely(!descs)) { + count = i; + break; + } + + desc_idx = 0; + sz = vq->desc[desc_idx].len / sizeof(*descs); + } else { + descs = vq->desc; + sz = vq->size; + } + + err = copy_mbuf_to_desc(dev, descs, pkts[i], desc_idx, sz); + if (unlikely(err)) { + used_idx = (start_idx + i) & (vq->size - 1); + vq->used->ring[used_idx].len = dev->vhost_hlen; + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, ring[used_idx]), + sizeof(vq->used->ring[used_idx])); + } + + if (i + 1 < count) + rte_prefetch0(&vq->desc[desc_indexes[i+1]]); + } + + rte_smp_wmb(); + + *(volatile uint16_t *)&vq->used->idx += count; + vq->last_used_idx += count; + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, idx), + sizeof(vq->used->idx)); + + /* flush used->idx update before we read avail->flags. */ + rte_mb(); + + /* Kick the guest if necessary. */ + if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT) + && (vq->callfd >= 0)) + eventfd_write(vq->callfd, (eventfd_t)1); + return count; +} + +static inline int __attribute__((always_inline)) +fill_vec_buf(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint32_t avail_idx, uint32_t *vec_idx, + struct buf_vector *buf_vec, uint16_t *desc_chain_head, + uint16_t *desc_chain_len) +{ + uint16_t idx = vq->avail->ring[avail_idx & (vq->size - 1)]; + uint32_t vec_id = *vec_idx; + uint32_t len = 0; + struct vring_desc *descs = vq->desc; + + *desc_chain_head = idx; + + if (vq->desc[idx].flags & VRING_DESC_F_INDIRECT) { + descs = (struct vring_desc *)(uintptr_t) + gpa_to_vva(dev, vq->desc[idx].addr); + if (unlikely(!descs)) + return -1; + + idx = 0; + } + + while (1) { + if (unlikely(vec_id >= BUF_VECTOR_MAX || idx >= vq->size)) + return -1; + + len += descs[idx].len; + buf_vec[vec_id].buf_addr = descs[idx].addr; + buf_vec[vec_id].buf_len = descs[idx].len; + buf_vec[vec_id].desc_idx = idx; + vec_id++; + + if ((descs[idx].flags & VRING_DESC_F_NEXT) == 0) + break; + + idx = descs[idx].next; + } + + *desc_chain_len = len; + *vec_idx = vec_id; + + return 0; +} + +/* + * Returns -1 on fail, 0 on success + */ +static inline int +reserve_avail_buf_mergeable(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint32_t size, struct buf_vector *buf_vec, + uint16_t *num_buffers, uint16_t avail_head) +{ + uint16_t cur_idx; + uint32_t vec_idx = 0; + uint16_t tries = 0; + + uint16_t head_idx = 0; + uint16_t len = 0; + + *num_buffers = 0; + cur_idx = vq->last_avail_idx; + + while (size > 0) { + if (unlikely(cur_idx == avail_head)) + return -1; + + if (unlikely(fill_vec_buf(dev, vq, cur_idx, &vec_idx, buf_vec, + &head_idx, &len) < 0)) + return -1; + len = RTE_MIN(len, size); + update_shadow_used_ring(vq, head_idx, len); + size -= len; + + cur_idx++; + tries++; + *num_buffers += 1; + + /* + * if we tried all available ring items, and still + * can't get enough buf, it means something abnormal + * happened. + */ + if (unlikely(tries >= vq->size)) + return -1; + } + + return 0; +} + +static inline int __attribute__((always_inline)) +copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m, + struct buf_vector *buf_vec, uint16_t num_buffers) +{ + struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0}; + uint32_t vec_idx = 0; + uint64_t desc_addr; + uint32_t mbuf_offset, mbuf_avail; + uint32_t desc_offset, desc_avail; + uint32_t cpy_len; + uint64_t hdr_addr, hdr_phys_addr; + struct rte_mbuf *hdr_mbuf; + + if (unlikely(m == NULL)) + return -1; + + desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr); + if (buf_vec[vec_idx].buf_len < dev->vhost_hlen || !desc_addr) + return -1; + + hdr_mbuf = m; + hdr_addr = desc_addr; + hdr_phys_addr = buf_vec[vec_idx].buf_addr; + rte_prefetch0((void *)(uintptr_t)hdr_addr); + + virtio_hdr.num_buffers = num_buffers; + LOG_DEBUG(VHOST_DATA, "(%d) RX: num merge buffers %d\n", + dev->vid, num_buffers); + + desc_avail = buf_vec[vec_idx].buf_len - dev->vhost_hlen; + desc_offset = dev->vhost_hlen; + + mbuf_avail = rte_pktmbuf_data_len(m); + mbuf_offset = 0; + while (mbuf_avail != 0 || m->next != NULL) { + /* done with current desc buf, get the next one */ + if (desc_avail == 0) { + vec_idx++; + desc_addr = gpa_to_vva(dev, buf_vec[vec_idx].buf_addr); + if (unlikely(!desc_addr)) + return -1; + + /* Prefetch buffer address. */ + rte_prefetch0((void *)(uintptr_t)desc_addr); + desc_offset = 0; + desc_avail = buf_vec[vec_idx].buf_len; + } + + /* done with current mbuf, get the next one */ + if (mbuf_avail == 0) { + m = m->next; + + mbuf_offset = 0; + mbuf_avail = rte_pktmbuf_data_len(m); + } + + if (hdr_addr) { + virtio_enqueue_offload(hdr_mbuf, &virtio_hdr.hdr); + copy_virtio_net_hdr(dev, hdr_addr, virtio_hdr); + vhost_log_write(dev, hdr_phys_addr, dev->vhost_hlen); + PRINT_PACKET(dev, (uintptr_t)hdr_addr, + dev->vhost_hlen, 0); + + hdr_addr = 0; + } + + cpy_len = RTE_MIN(desc_avail, mbuf_avail); + rte_memcpy((void *)((uintptr_t)(desc_addr + desc_offset)), + rte_pktmbuf_mtod_offset(m, void *, mbuf_offset), + cpy_len); + vhost_log_write(dev, buf_vec[vec_idx].buf_addr + desc_offset, + cpy_len); + PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset), + cpy_len, 0); + + mbuf_avail -= cpy_len; + mbuf_offset += cpy_len; + desc_avail -= cpy_len; + desc_offset += cpy_len; + } + + return 0; +} + +static inline uint32_t __attribute__((always_inline)) +virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id, + struct rte_mbuf **pkts, uint32_t count) +{ + struct vhost_virtqueue *vq; + uint32_t pkt_idx = 0; + uint16_t num_buffers; + struct buf_vector buf_vec[BUF_VECTOR_MAX]; + uint16_t avail_head; + + LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__); + if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->virt_qp_nb))) { + RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n", + dev->vid, __func__, queue_id); + return 0; + } + + vq = dev->virtqueue[queue_id]; + if (unlikely(vq->enabled == 0)) + return 0; + + count = RTE_MIN((uint32_t)MAX_PKT_BURST, count); + if (count == 0) + return 0; + + rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]); + + vq->shadow_used_idx = 0; + avail_head = *((volatile uint16_t *)&vq->avail->idx); + for (pkt_idx = 0; pkt_idx < count; pkt_idx++) { + uint32_t pkt_len = pkts[pkt_idx]->pkt_len + dev->vhost_hlen; + + if (unlikely(reserve_avail_buf_mergeable(dev, vq, + pkt_len, buf_vec, &num_buffers, + avail_head) < 0)) { + LOG_DEBUG(VHOST_DATA, + "(%d) failed to get enough desc from vring\n", + dev->vid); + vq->shadow_used_idx -= num_buffers; + break; + } + + LOG_DEBUG(VHOST_DATA, "(%d) current index %d | end index %d\n", + dev->vid, vq->last_avail_idx, + vq->last_avail_idx + num_buffers); + + if (copy_mbuf_to_desc_mergeable(dev, pkts[pkt_idx], + buf_vec, num_buffers) < 0) { + vq->shadow_used_idx -= num_buffers; + break; + } + + vq->last_avail_idx += num_buffers; + } + + if (likely(vq->shadow_used_idx)) { + flush_shadow_used_ring(dev, vq); + + /* flush used->idx update before we read avail->flags. */ + rte_mb(); + + /* Kick the guest if necessary. */ + if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT) + && (vq->callfd >= 0)) + eventfd_write(vq->callfd, (eventfd_t)1); + } + + return pkt_idx; +} + +uint16_t +rte_vhost_enqueue_burst(int vid, uint16_t queue_id, + struct rte_mbuf **pkts, uint16_t count) +{ + struct virtio_net *dev = get_device(vid); + + if (!dev) + return 0; + + if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF)) + return virtio_dev_merge_rx(dev, queue_id, pkts, count); + else + return virtio_dev_rx(dev, queue_id, pkts, count); +} + +static inline bool +virtio_net_with_host_offload(struct virtio_net *dev) +{ + if (dev->features & + (VIRTIO_NET_F_CSUM | VIRTIO_NET_F_HOST_ECN | + VIRTIO_NET_F_HOST_TSO4 | VIRTIO_NET_F_HOST_TSO6 | + VIRTIO_NET_F_HOST_UFO)) + return true; + + return false; +} + +static void +parse_ethernet(struct rte_mbuf *m, uint16_t *l4_proto, void **l4_hdr) +{ + struct ipv4_hdr *ipv4_hdr; + struct ipv6_hdr *ipv6_hdr; + void *l3_hdr = NULL; + struct ether_hdr *eth_hdr; + uint16_t ethertype; + + eth_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *); + + m->l2_len = sizeof(struct ether_hdr); + ethertype = rte_be_to_cpu_16(eth_hdr->ether_type); + + if (ethertype == ETHER_TYPE_VLAN) { + struct vlan_hdr *vlan_hdr = (struct vlan_hdr *)(eth_hdr + 1); + + m->l2_len += sizeof(struct vlan_hdr); + ethertype = rte_be_to_cpu_16(vlan_hdr->eth_proto); + } + + l3_hdr = (char *)eth_hdr + m->l2_len; + + switch (ethertype) { + case ETHER_TYPE_IPv4: + ipv4_hdr = (struct ipv4_hdr *)l3_hdr; + *l4_proto = ipv4_hdr->next_proto_id; + m->l3_len = (ipv4_hdr->version_ihl & 0x0f) * 4; + *l4_hdr = (char *)l3_hdr + m->l3_len; + m->ol_flags |= PKT_TX_IPV4; + break; + case ETHER_TYPE_IPv6: + ipv6_hdr = (struct ipv6_hdr *)l3_hdr; + *l4_proto = ipv6_hdr->proto; + m->l3_len = sizeof(struct ipv6_hdr); + *l4_hdr = (char *)l3_hdr + m->l3_len; + m->ol_flags |= PKT_TX_IPV6; + break; + default: + m->l3_len = 0; + *l4_proto = 0; + break; + } +} + +static inline void __attribute__((always_inline)) +vhost_dequeue_offload(struct virtio_net_hdr *hdr, struct rte_mbuf *m) +{ + uint16_t l4_proto = 0; + void *l4_hdr = NULL; + struct tcp_hdr *tcp_hdr = NULL; + + if (hdr->flags == 0 && hdr->gso_type == VIRTIO_NET_HDR_GSO_NONE) + return; + + parse_ethernet(m, &l4_proto, &l4_hdr); + if (hdr->flags == VIRTIO_NET_HDR_F_NEEDS_CSUM) { + if (hdr->csum_start == (m->l2_len + m->l3_len)) { + switch (hdr->csum_offset) { + case (offsetof(struct tcp_hdr, cksum)): + if (l4_proto == IPPROTO_TCP) + m->ol_flags |= PKT_TX_TCP_CKSUM; + break; + case (offsetof(struct udp_hdr, dgram_cksum)): + if (l4_proto == IPPROTO_UDP) + m->ol_flags |= PKT_TX_UDP_CKSUM; + break; + case (offsetof(struct sctp_hdr, cksum)): + if (l4_proto == IPPROTO_SCTP) + m->ol_flags |= PKT_TX_SCTP_CKSUM; + break; + default: + break; + } + } + } + + if (hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) { + switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { + case VIRTIO_NET_HDR_GSO_TCPV4: + case VIRTIO_NET_HDR_GSO_TCPV6: + tcp_hdr = (struct tcp_hdr *)l4_hdr; + m->ol_flags |= PKT_TX_TCP_SEG; + m->tso_segsz = hdr->gso_size; + m->l4_len = (tcp_hdr->data_off & 0xf0) >> 2; + break; + default: + RTE_LOG(WARNING, VHOST_DATA, + "unsupported gso type %u.\n", hdr->gso_type); + break; + } + } +} + +#define RARP_PKT_SIZE 64 + +static int +make_rarp_packet(struct rte_mbuf *rarp_mbuf, const struct ether_addr *mac) +{ + struct ether_hdr *eth_hdr; + struct arp_hdr *rarp; + + if (rarp_mbuf->buf_len < 64) { + RTE_LOG(WARNING, VHOST_DATA, + "failed to make RARP; mbuf size too small %u (< %d)\n", + rarp_mbuf->buf_len, RARP_PKT_SIZE); + return -1; + } + + /* Ethernet header. */ + eth_hdr = rte_pktmbuf_mtod_offset(rarp_mbuf, struct ether_hdr *, 0); + memset(eth_hdr->d_addr.addr_bytes, 0xff, ETHER_ADDR_LEN); + ether_addr_copy(mac, ð_hdr->s_addr); + eth_hdr->ether_type = htons(ETHER_TYPE_RARP); + + /* RARP header. */ + rarp = (struct arp_hdr *)(eth_hdr + 1); + rarp->arp_hrd = htons(ARP_HRD_ETHER); + rarp->arp_pro = htons(ETHER_TYPE_IPv4); + rarp->arp_hln = ETHER_ADDR_LEN; + rarp->arp_pln = 4; + rarp->arp_op = htons(ARP_OP_REVREQUEST); + + ether_addr_copy(mac, &rarp->arp_data.arp_sha); + ether_addr_copy(mac, &rarp->arp_data.arp_tha); + memset(&rarp->arp_data.arp_sip, 0x00, 4); + memset(&rarp->arp_data.arp_tip, 0x00, 4); + + rarp_mbuf->pkt_len = rarp_mbuf->data_len = RARP_PKT_SIZE; + + return 0; +} + +static inline void __attribute__((always_inline)) +put_zmbuf(struct zcopy_mbuf *zmbuf) +{ + zmbuf->in_use = 0; +} + +static inline int __attribute__((always_inline)) +copy_desc_to_mbuf(struct virtio_net *dev, struct vring_desc *descs, + uint16_t max_desc, struct rte_mbuf *m, uint16_t desc_idx, + struct rte_mempool *mbuf_pool) +{ + struct vring_desc *desc; + uint64_t desc_addr; + uint32_t desc_avail, desc_offset; + uint32_t mbuf_avail, mbuf_offset; + uint32_t cpy_len; + struct rte_mbuf *cur = m, *prev = m; + struct virtio_net_hdr *hdr = NULL; + /* A counter to avoid desc dead loop chain */ + uint32_t nr_desc = 1; + + desc = &descs[desc_idx]; + if (unlikely((desc->len < dev->vhost_hlen)) || + (desc->flags & VRING_DESC_F_INDIRECT)) + return -1; + + desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + + if (virtio_net_with_host_offload(dev)) { + hdr = (struct virtio_net_hdr *)((uintptr_t)desc_addr); + rte_prefetch0(hdr); + } + + /* + * A virtio driver normally uses at least 2 desc buffers + * for Tx: the first for storing the header, and others + * for storing the data. + */ + if (likely((desc->len == dev->vhost_hlen) && + (desc->flags & VRING_DESC_F_NEXT) != 0)) { + desc = &descs[desc->next]; + if (unlikely(desc->flags & VRING_DESC_F_INDIRECT)) + return -1; + + desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + + desc_offset = 0; + desc_avail = desc->len; + nr_desc += 1; + } else { + desc_avail = desc->len - dev->vhost_hlen; + desc_offset = dev->vhost_hlen; + } + + rte_prefetch0((void *)(uintptr_t)(desc_addr + desc_offset)); + + PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset), desc_avail, 0); + + mbuf_offset = 0; + mbuf_avail = m->buf_len - RTE_PKTMBUF_HEADROOM; + while (1) { + uint64_t hpa; + + cpy_len = RTE_MIN(desc_avail, mbuf_avail); + + /* + * A desc buf might across two host physical pages that are + * not continuous. In such case (gpa_to_hpa returns 0), data + * will be copied even though zero copy is enabled. + */ + if (unlikely(dev->dequeue_zero_copy && (hpa = gpa_to_hpa(dev, + desc->addr + desc_offset, cpy_len)))) { + cur->data_len = cpy_len; + cur->data_off = 0; + cur->buf_addr = (void *)(uintptr_t)desc_addr; + cur->buf_physaddr = hpa; + + /* + * In zero copy mode, one mbuf can only reference data + * for one or partial of one desc buff. + */ + mbuf_avail = cpy_len; + } else { + rte_memcpy(rte_pktmbuf_mtod_offset(cur, void *, + mbuf_offset), + (void *)((uintptr_t)(desc_addr + desc_offset)), + cpy_len); + } + + mbuf_avail -= cpy_len; + mbuf_offset += cpy_len; + desc_avail -= cpy_len; + desc_offset += cpy_len; + + /* This desc reaches to its end, get the next one */ + if (desc_avail == 0) { + if ((desc->flags & VRING_DESC_F_NEXT) == 0) + break; + + if (unlikely(desc->next >= max_desc || + ++nr_desc > max_desc)) + return -1; + desc = &descs[desc->next]; + if (unlikely(desc->flags & VRING_DESC_F_INDIRECT)) + return -1; + + desc_addr = gpa_to_vva(dev, desc->addr); + if (unlikely(!desc_addr)) + return -1; + + rte_prefetch0((void *)(uintptr_t)desc_addr); + + desc_offset = 0; + desc_avail = desc->len; + + PRINT_PACKET(dev, (uintptr_t)desc_addr, desc->len, 0); + } + + /* + * This mbuf reaches to its end, get a new one + * to hold more data. + */ + if (mbuf_avail == 0) { + cur = rte_pktmbuf_alloc(mbuf_pool); + if (unlikely(cur == NULL)) { + RTE_LOG(ERR, VHOST_DATA, "Failed to " + "allocate memory for mbuf.\n"); + return -1; + } + + prev->next = cur; + prev->data_len = mbuf_offset; + m->nb_segs += 1; + m->pkt_len += mbuf_offset; + prev = cur; + + mbuf_offset = 0; + mbuf_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM; + } + } + + prev->data_len = mbuf_offset; + m->pkt_len += mbuf_offset; + + if (hdr) + vhost_dequeue_offload(hdr, m); + + return 0; +} + +static inline void __attribute__((always_inline)) +update_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint32_t used_idx, uint32_t desc_idx) +{ + vq->used->ring[used_idx].id = desc_idx; + vq->used->ring[used_idx].len = 0; + vhost_log_used_vring(dev, vq, + offsetof(struct vring_used, ring[used_idx]), + sizeof(vq->used->ring[used_idx])); +} + +static inline void __attribute__((always_inline)) +update_used_idx(struct virtio_net *dev, struct vhost_virtqueue *vq, + uint32_t count) +{ + if (unlikely(count == 0)) + return; + + rte_smp_wmb(); + rte_smp_rmb(); + + vq->used->idx += count; + vhost_log_used_vring(dev, vq, offsetof(struct vring_used, idx), + sizeof(vq->used->idx)); + + /* Kick guest if required. */ + if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT) + && (vq->callfd >= 0)) + eventfd_write(vq->callfd, (eventfd_t)1); +} + +static inline struct zcopy_mbuf *__attribute__((always_inline)) +get_zmbuf(struct vhost_virtqueue *vq) +{ + uint16_t i; + uint16_t last; + int tries = 0; + + /* search [last_zmbuf_idx, zmbuf_size) */ + i = vq->last_zmbuf_idx; + last = vq->zmbuf_size; + +again: + for (; i < last; i++) { + if (vq->zmbufs[i].in_use == 0) { + vq->last_zmbuf_idx = i + 1; + vq->zmbufs[i].in_use = 1; + return &vq->zmbufs[i]; + } + } + + tries++; + if (tries == 1) { + /* search [0, last_zmbuf_idx) */ + i = 0; + last = vq->last_zmbuf_idx; + goto again; + } + + return NULL; +} + +static inline bool __attribute__((always_inline)) +mbuf_is_consumed(struct rte_mbuf *m) +{ + while (m) { + if (rte_mbuf_refcnt_read(m) > 1) + return false; + m = m->next; + } + + return true; +} + +uint16_t +rte_vhost_dequeue_burst(int vid, uint16_t queue_id, + struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count) +{ + struct virtio_net *dev; + struct rte_mbuf *rarp_mbuf = NULL; + struct vhost_virtqueue *vq; + uint32_t desc_indexes[MAX_PKT_BURST]; + uint32_t used_idx; + uint32_t i = 0; + uint16_t free_entries; + uint16_t avail_idx; + + dev = get_device(vid); + if (!dev) + return 0; + + if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->virt_qp_nb))) { + RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n", + dev->vid, __func__, queue_id); + return 0; + } + + vq = dev->virtqueue[queue_id]; + if (unlikely(vq->enabled == 0)) + return 0; + + if (unlikely(dev->dequeue_zero_copy)) { + struct zcopy_mbuf *zmbuf, *next; + int nr_updated = 0; + + for (zmbuf = TAILQ_FIRST(&vq->zmbuf_list); + zmbuf != NULL; zmbuf = next) { + next = TAILQ_NEXT(zmbuf, next); + + if (mbuf_is_consumed(zmbuf->mbuf)) { + used_idx = vq->last_used_idx++ & (vq->size - 1); + update_used_ring(dev, vq, used_idx, + zmbuf->desc_idx); + nr_updated += 1; + + TAILQ_REMOVE(&vq->zmbuf_list, zmbuf, next); + rte_pktmbuf_free(zmbuf->mbuf); + put_zmbuf(zmbuf); + vq->nr_zmbuf -= 1; + } + } + + update_used_idx(dev, vq, nr_updated); + } + + /* + * Construct a RARP broadcast packet, and inject it to the "pkts" + * array, to looks like that guest actually send such packet. + * + * Check user_send_rarp() for more information. + */ + if (unlikely(rte_atomic16_cmpset((volatile uint16_t *) + &dev->broadcast_rarp.cnt, 1, 0))) { + rarp_mbuf = rte_pktmbuf_alloc(mbuf_pool); + if (rarp_mbuf == NULL) { + RTE_LOG(ERR, VHOST_DATA, + "Failed to allocate memory for mbuf.\n"); + return 0; + } + + if (make_rarp_packet(rarp_mbuf, &dev->mac)) { + rte_pktmbuf_free(rarp_mbuf); + rarp_mbuf = NULL; + } else { + count -= 1; + } + } + + free_entries = *((volatile uint16_t *)&vq->avail->idx) - + vq->last_avail_idx; + if (free_entries == 0) + goto out; + + LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__); + + /* Prefetch available and used ring */ + avail_idx = vq->last_avail_idx & (vq->size - 1); + used_idx = vq->last_used_idx & (vq->size - 1); + rte_prefetch0(&vq->avail->ring[avail_idx]); + rte_prefetch0(&vq->used->ring[used_idx]); + + count = RTE_MIN(count, MAX_PKT_BURST); + count = RTE_MIN(count, free_entries); + LOG_DEBUG(VHOST_DATA, "(%d) about to dequeue %u buffers\n", + dev->vid, count); + + /* Retrieve all of the head indexes first to avoid caching issues. */ + for (i = 0; i < count; i++) { + avail_idx = (vq->last_avail_idx + i) & (vq->size - 1); + used_idx = (vq->last_used_idx + i) & (vq->size - 1); + desc_indexes[i] = vq->avail->ring[avail_idx]; + + if (likely(dev->dequeue_zero_copy == 0)) + update_used_ring(dev, vq, used_idx, desc_indexes[i]); + } + + /* Prefetch descriptor index. */ + rte_prefetch0(&vq->desc[desc_indexes[0]]); + for (i = 0; i < count; i++) { + struct vring_desc *desc; + uint16_t sz, idx; + int err; + + if (likely(i + 1 < count)) + rte_prefetch0(&vq->desc[desc_indexes[i + 1]]); + + if (vq->desc[desc_indexes[i]].flags & VRING_DESC_F_INDIRECT) { + desc = (struct vring_desc *)(uintptr_t)gpa_to_vva(dev, + vq->desc[desc_indexes[i]].addr); + if (unlikely(!desc)) + break; + + rte_prefetch0(desc); + sz = vq->desc[desc_indexes[i]].len / sizeof(*desc); + idx = 0; + } else { + desc = vq->desc; + sz = vq->size; + idx = desc_indexes[i]; + } + + pkts[i] = rte_pktmbuf_alloc(mbuf_pool); + if (unlikely(pkts[i] == NULL)) { + RTE_LOG(ERR, VHOST_DATA, + "Failed to allocate memory for mbuf.\n"); + break; + } + + err = copy_desc_to_mbuf(dev, desc, sz, pkts[i], idx, mbuf_pool); + if (unlikely(err)) { + rte_pktmbuf_free(pkts[i]); + break; + } + + if (unlikely(dev->dequeue_zero_copy)) { + struct zcopy_mbuf *zmbuf; + + zmbuf = get_zmbuf(vq); + if (!zmbuf) { + rte_pktmbuf_free(pkts[i]); + break; + } + zmbuf->mbuf = pkts[i]; + zmbuf->desc_idx = desc_indexes[i]; + + /* + * Pin lock the mbuf; we will check later to see + * whether the mbuf is freed (when we are the last + * user) or not. If that's the case, we then could + * update the used ring safely. + */ + rte_mbuf_refcnt_update(pkts[i], 1); + + vq->nr_zmbuf += 1; + TAILQ_INSERT_TAIL(&vq->zmbuf_list, zmbuf, next); + } + } + vq->last_avail_idx += i; + + if (likely(dev->dequeue_zero_copy == 0)) { + vq->last_used_idx += i; + update_used_idx(dev, vq, i); + } + +out: + if (unlikely(rarp_mbuf != NULL)) { + /* + * Inject it to the head of "pkts" array, so that switch's mac + * learning table will get updated first. + */ + memmove(&pkts[1], pkts, i * sizeof(struct rte_mbuf *)); + pkts[0] = rarp_mbuf; + i += 1; + } + + return i; +} |