diff options
Diffstat (limited to 'hw/virtio-net.c')
| -rw-r--r-- | hw/virtio-net.c | 176 |
1 files changed, 97 insertions, 79 deletions
diff --git a/hw/virtio-net.c b/hw/virtio-net.c index 50ba728c02..108ce07cfc 100644 --- a/hw/virtio-net.c +++ b/hw/virtio-net.c @@ -41,6 +41,8 @@ typedef struct VirtIONet int32_t tx_burst; int tx_waiting; uint32_t has_vnet_hdr; + size_t host_hdr_len; + size_t guest_hdr_len; uint8_t has_ufo; struct { VirtQueueElement elem; @@ -200,16 +202,19 @@ static void virtio_net_reset(VirtIODevice *vdev) memset(n->vlans, 0, MAX_VLAN >> 3); } -static int peer_has_vnet_hdr(VirtIONet *n) +static void peer_test_vnet_hdr(VirtIONet *n) { if (!n->nic->nc.peer) - return 0; + return; if (n->nic->nc.peer->info->type != NET_CLIENT_OPTIONS_KIND_TAP) - return 0; + return; n->has_vnet_hdr = tap_has_vnet_hdr(n->nic->nc.peer); +} +static int peer_has_vnet_hdr(VirtIONet *n) +{ return n->has_vnet_hdr; } @@ -223,15 +228,27 @@ static int peer_has_ufo(VirtIONet *n) return n->has_ufo; } +static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs) +{ + n->mergeable_rx_bufs = mergeable_rx_bufs; + + n->guest_hdr_len = n->mergeable_rx_bufs ? + sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr); + + if (peer_has_vnet_hdr(n) && + tap_has_vnet_hdr_len(n->nic->nc.peer, n->guest_hdr_len)) { + tap_set_vnet_hdr_len(n->nic->nc.peer, n->guest_hdr_len); + n->host_hdr_len = n->guest_hdr_len; + } +} + static uint32_t virtio_net_get_features(VirtIODevice *vdev, uint32_t features) { VirtIONet *n = to_virtio_net(vdev); features |= (1 << VIRTIO_NET_F_MAC); - if (peer_has_vnet_hdr(n)) { - tap_using_vnet_hdr(n->nic->nc.peer, 1); - } else { + if (!peer_has_vnet_hdr(n)) { features &= ~(0x1 << VIRTIO_NET_F_CSUM); features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO4); features &= ~(0x1 << VIRTIO_NET_F_HOST_TSO6); @@ -277,7 +294,7 @@ static void virtio_net_set_features(VirtIODevice *vdev, uint32_t features) { VirtIONet *n = to_virtio_net(vdev); - n->mergeable_rx_bufs = !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF)); + virtio_net_set_mrg_rx_bufs(n, !!(features & (1 << VIRTIO_NET_F_MRG_RXBUF))); if (n->has_vnet_hdr) { tap_set_offload(n->nic->nc.peer, @@ -499,41 +516,34 @@ static int virtio_net_has_buffers(VirtIONet *n, int bufsize) * cache. */ static void work_around_broken_dhclient(struct virtio_net_hdr *hdr, - const uint8_t *buf, size_t size) + uint8_t *buf, size_t size) { if ((hdr->flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && /* missing csum */ (size > 27 && size < 1500) && /* normal sized MTU */ (buf[12] == 0x08 && buf[13] == 0x00) && /* ethertype == IPv4 */ (buf[23] == 17) && /* ip.protocol == UDP */ (buf[34] == 0 && buf[35] == 67)) { /* udp.srcport == bootps */ - /* FIXME this cast is evil */ - net_checksum_calculate((uint8_t *)buf, size); + net_checksum_calculate(buf, size); hdr->flags &= ~VIRTIO_NET_HDR_F_NEEDS_CSUM; } } -static int receive_header(VirtIONet *n, struct iovec *iov, int iovcnt, - const void *buf, size_t size, size_t hdr_len) +static void receive_header(VirtIONet *n, const struct iovec *iov, int iov_cnt, + const void *buf, size_t size) { - struct virtio_net_hdr *hdr = (struct virtio_net_hdr *)iov[0].iov_base; - int offset = 0; - - hdr->flags = 0; - hdr->gso_type = VIRTIO_NET_HDR_GSO_NONE; - if (n->has_vnet_hdr) { - memcpy(hdr, buf, sizeof(*hdr)); - offset = sizeof(*hdr); - work_around_broken_dhclient(hdr, buf + offset, size - offset); + /* FIXME this cast is evil */ + void *wbuf = (void *)buf; + work_around_broken_dhclient(wbuf, wbuf + n->host_hdr_len, + size - n->host_hdr_len); + iov_from_buf(iov, iov_cnt, 0, buf, sizeof(struct virtio_net_hdr)); + } else { + struct virtio_net_hdr hdr = { + .flags = 0, + .gso_type = VIRTIO_NET_HDR_GSO_NONE + }; + iov_from_buf(iov, iov_cnt, 0, &hdr, sizeof hdr); } - - /* We only ever receive a struct virtio_net_hdr from the tapfd, - * but we may be passing along a larger header to the guest. - */ - iov[0].iov_base += hdr_len; - iov[0].iov_len -= hdr_len; - - return offset; } static int receive_filter(VirtIONet *n, const uint8_t *buf, int size) @@ -546,9 +556,7 @@ static int receive_filter(VirtIONet *n, const uint8_t *buf, int size) if (n->promisc) return 1; - if (n->has_vnet_hdr) { - ptr += sizeof(struct virtio_net_hdr); - } + ptr += n->host_hdr_len; if (!memcmp(&ptr[12], vlan, sizeof(vlan))) { int vid = be16_to_cpup((uint16_t *)(ptr + 14)) & 0xfff; @@ -592,19 +600,16 @@ static int receive_filter(VirtIONet *n, const uint8_t *buf, int size) static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t size) { VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque; - struct virtio_net_hdr_mrg_rxbuf *mhdr = NULL; - size_t guest_hdr_len, offset, i, host_hdr_len; + struct iovec mhdr_sg[VIRTQUEUE_MAX_SIZE]; + struct virtio_net_hdr_mrg_rxbuf mhdr; + unsigned mhdr_cnt = 0; + size_t offset, i, guest_offset; if (!virtio_net_can_receive(&n->nic->nc)) return -1; /* hdr_len refers to the header we supply to the guest */ - guest_hdr_len = n->mergeable_rx_bufs ? - sizeof(struct virtio_net_hdr_mrg_rxbuf) : sizeof(struct virtio_net_hdr); - - - host_hdr_len = n->has_vnet_hdr ? sizeof(struct virtio_net_hdr) : 0; - if (!virtio_net_has_buffers(n, size + guest_hdr_len - host_hdr_len)) + if (!virtio_net_has_buffers(n, size + n->guest_hdr_len - n->host_hdr_len)) return 0; if (!receive_filter(n, buf, size)) @@ -615,7 +620,7 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t while (offset < size) { VirtQueueElement elem; int len, total; - struct iovec sg[VIRTQUEUE_MAX_SIZE]; + const struct iovec *sg = elem.in_sg; total = 0; @@ -626,7 +631,7 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t "i %zd mergeable %d offset %zd, size %zd, " "guest hdr len %zd, host hdr len %zd guest features 0x%x", i, n->mergeable_rx_bufs, offset, size, - guest_hdr_len, host_hdr_len, n->vdev.guest_features); + n->guest_hdr_len, n->host_hdr_len, n->vdev.guest_features); exit(1); } @@ -635,24 +640,25 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t exit(1); } - if (!n->mergeable_rx_bufs && elem.in_sg[0].iov_len != guest_hdr_len) { - error_report("virtio-net header not in first element"); - exit(1); - } - - memcpy(&sg, &elem.in_sg[0], sizeof(sg[0]) * elem.in_num); - if (i == 0) { - if (n->mergeable_rx_bufs) - mhdr = (struct virtio_net_hdr_mrg_rxbuf *)sg[0].iov_base; + assert(offset == 0); + if (n->mergeable_rx_bufs) { + mhdr_cnt = iov_copy(mhdr_sg, ARRAY_SIZE(mhdr_sg), + sg, elem.in_num, + offsetof(typeof(mhdr), num_buffers), + sizeof(mhdr.num_buffers)); + } - offset += receive_header(n, sg, elem.in_num, - buf + offset, size - offset, guest_hdr_len); - total += guest_hdr_len; + receive_header(n, sg, elem.in_num, buf, size); + offset = n->host_hdr_len; + total += n->guest_hdr_len; + guest_offset = n->guest_hdr_len; + } else { + guest_offset = 0; } /* copy in packet. ugh */ - len = iov_from_buf(sg, elem.in_num, 0, + len = iov_from_buf(sg, elem.in_num, guest_offset, buf + offset, size - offset); total += len; offset += len; @@ -665,7 +671,7 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t "i %zd mergeable %d offset %zd, size %zd, " "guest hdr len %zd, host hdr len %zd", i, n->mergeable_rx_bufs, - offset, size, guest_hdr_len, host_hdr_len); + offset, size, n->guest_hdr_len, n->host_hdr_len); #endif return size; } @@ -674,8 +680,11 @@ static ssize_t virtio_net_receive(NetClientState *nc, const uint8_t *buf, size_t virtqueue_fill(n->rx_vq, &elem, total, i++); } - if (mhdr) { - stw_p(&mhdr->num_buffers, i); + if (mhdr_cnt) { + stw_p(&mhdr.num_buffers, i); + iov_from_buf(mhdr_sg, mhdr_cnt, + 0, + &mhdr.num_buffers, sizeof mhdr.num_buffers); } virtqueue_flush(n->rx_vq, i); @@ -716,33 +725,35 @@ static int32_t virtio_net_flush_tx(VirtIONet *n, VirtQueue *vq) } while (virtqueue_pop(vq, &elem)) { - ssize_t ret, len = 0; + ssize_t ret, len; unsigned int out_num = elem.out_num; struct iovec *out_sg = &elem.out_sg[0]; - unsigned hdr_len; - - /* hdr_len refers to the header received from the guest */ - hdr_len = n->mergeable_rx_bufs ? - sizeof(struct virtio_net_hdr_mrg_rxbuf) : - sizeof(struct virtio_net_hdr); + struct iovec sg[VIRTQUEUE_MAX_SIZE]; - if (out_num < 1 || out_sg->iov_len != hdr_len) { + if (out_num < 1) { error_report("virtio-net header not in first element"); exit(1); } - /* ignore the header if GSO is not supported */ - if (!n->has_vnet_hdr) { - out_num--; - out_sg++; - len += hdr_len; - } else if (n->mergeable_rx_bufs) { - /* tapfd expects a struct virtio_net_hdr */ - hdr_len -= sizeof(struct virtio_net_hdr); - out_sg->iov_len -= hdr_len; - len += hdr_len; + /* + * If host wants to see the guest header as is, we can + * pass it on unchanged. Otherwise, copy just the parts + * that host is interested in. + */ + assert(n->host_hdr_len <= n->guest_hdr_len); + if (n->host_hdr_len != n->guest_hdr_len) { + unsigned sg_num = iov_copy(sg, ARRAY_SIZE(sg), + out_sg, out_num, + 0, n->host_hdr_len); + sg_num += iov_copy(sg + sg_num, ARRAY_SIZE(sg) - sg_num, + out_sg, out_num, + n->guest_hdr_len, -1); + out_num = sg_num; + out_sg = sg; } + len = n->guest_hdr_len; + ret = qemu_sendv_packet_async(&n->nic->nc, out_sg, out_num, virtio_net_tx_complete); if (ret == 0) { @@ -899,7 +910,8 @@ static int virtio_net_load(QEMUFile *f, void *opaque, int version_id) qemu_get_buffer(f, n->mac, ETH_ALEN); n->tx_waiting = qemu_get_be32(f); - n->mergeable_rx_bufs = qemu_get_be32(f); + + virtio_net_set_mrg_rx_bufs(n, qemu_get_be32(f)); if (version_id >= 3) n->status = qemu_get_be16(f); @@ -939,7 +951,6 @@ static int virtio_net_load(QEMUFile *f, void *opaque, int version_id) } if (n->has_vnet_hdr) { - tap_using_vnet_hdr(n->nic->nc.peer, 1); tap_set_offload(n->nic->nc.peer, (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_CSUM) & 1, (n->vdev.guest_features >> VIRTIO_NET_F_GUEST_TSO4) & 1, @@ -1038,12 +1049,19 @@ VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf, n->status = VIRTIO_NET_S_LINK_UP; n->nic = qemu_new_nic(&net_virtio_info, conf, object_get_typename(OBJECT(dev)), dev->id, n); + peer_test_vnet_hdr(n); + if (peer_has_vnet_hdr(n)) { + tap_using_vnet_hdr(n->nic->nc.peer, 1); + n->host_hdr_len = sizeof(struct virtio_net_hdr); + } else { + n->host_hdr_len = 0; + } qemu_format_nic_info_str(&n->nic->nc, conf->macaddr.a); n->tx_waiting = 0; n->tx_burst = net->txburst; - n->mergeable_rx_bufs = 0; + virtio_net_set_mrg_rx_bufs(n, 0); n->promisc = 1; /* for compatibility */ n->mac_table.macs = g_malloc0(MAC_TABLE_ENTRIES * ETH_ALEN); |