diff options
Diffstat (limited to 'hw/net/net_tx_pkt.c')
-rw-r--r-- | hw/net/net_tx_pkt.c | 637 |
1 files changed, 637 insertions, 0 deletions
diff --git a/hw/net/net_tx_pkt.c b/hw/net/net_tx_pkt.c new file mode 100644 index 0000000000..e4478bead8 --- /dev/null +++ b/hw/net/net_tx_pkt.c @@ -0,0 +1,637 @@ +/* + * QEMU TX packets abstractions + * + * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com) + * + * Developed by Daynix Computing LTD (http://www.daynix.com) + * + * Authors: + * Dmitry Fleytman <dmitry@daynix.com> + * Tamir Shomer <tamirs@daynix.com> + * Yan Vugenfirer <yan@daynix.com> + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + * + */ + +#include "net_tx_pkt.h" +#include "net/eth.h" +#include "net/checksum.h" +#include "net/tap.h" +#include "net/net.h" +#include "hw/pci/pci.h" + +enum { + NET_TX_PKT_VHDR_FRAG = 0, + NET_TX_PKT_L2HDR_FRAG, + NET_TX_PKT_L3HDR_FRAG, + NET_TX_PKT_PL_START_FRAG +}; + +/* TX packet private context */ +struct NetTxPkt { + PCIDevice *pci_dev; + + struct virtio_net_hdr virt_hdr; + bool has_virt_hdr; + + struct iovec *raw; + uint32_t raw_frags; + uint32_t max_raw_frags; + + struct iovec *vec; + + uint8_t l2_hdr[ETH_MAX_L2_HDR_LEN]; + uint8_t l3_hdr[ETH_MAX_IP_DGRAM_LEN]; + + uint32_t payload_len; + + uint32_t payload_frags; + uint32_t max_payload_frags; + + uint16_t hdr_len; + eth_pkt_types_e packet_type; + uint8_t l4proto; + + bool is_loopback; +}; + +void net_tx_pkt_init(struct NetTxPkt **pkt, PCIDevice *pci_dev, + uint32_t max_frags, bool has_virt_hdr) +{ + struct NetTxPkt *p = g_malloc0(sizeof *p); + + p->pci_dev = pci_dev; + + p->vec = g_malloc((sizeof *p->vec) * + (max_frags + NET_TX_PKT_PL_START_FRAG)); + + p->raw = g_malloc((sizeof *p->raw) * max_frags); + + p->max_payload_frags = max_frags; + p->max_raw_frags = max_frags; + p->has_virt_hdr = has_virt_hdr; + p->vec[NET_TX_PKT_VHDR_FRAG].iov_base = &p->virt_hdr; + p->vec[NET_TX_PKT_VHDR_FRAG].iov_len = + p->has_virt_hdr ? sizeof p->virt_hdr : 0; + p->vec[NET_TX_PKT_L2HDR_FRAG].iov_base = &p->l2_hdr; + p->vec[NET_TX_PKT_L3HDR_FRAG].iov_base = &p->l3_hdr; + + *pkt = p; +} + +void net_tx_pkt_uninit(struct NetTxPkt *pkt) +{ + if (pkt) { + g_free(pkt->vec); + g_free(pkt->raw); + g_free(pkt); + } +} + +void net_tx_pkt_update_ip_hdr_checksum(struct NetTxPkt *pkt) +{ + uint16_t csum; + assert(pkt); + struct ip_header *ip_hdr; + ip_hdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; + + ip_hdr->ip_len = cpu_to_be16(pkt->payload_len + + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len); + + ip_hdr->ip_sum = 0; + csum = net_raw_checksum((uint8_t *)ip_hdr, + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len); + ip_hdr->ip_sum = cpu_to_be16(csum); +} + +void net_tx_pkt_update_ip_checksums(struct NetTxPkt *pkt) +{ + uint16_t csum; + uint32_t cntr, cso; + assert(pkt); + uint8_t gso_type = pkt->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN; + void *ip_hdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; + + if (pkt->payload_len + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len > + ETH_MAX_IP_DGRAM_LEN) { + return; + } + + if (gso_type == VIRTIO_NET_HDR_GSO_TCPV4 || + gso_type == VIRTIO_NET_HDR_GSO_UDP) { + /* Calculate IP header checksum */ + net_tx_pkt_update_ip_hdr_checksum(pkt); + + /* Calculate IP pseudo header checksum */ + cntr = eth_calc_ip4_pseudo_hdr_csum(ip_hdr, pkt->payload_len, &cso); + csum = cpu_to_be16(~net_checksum_finish(cntr)); + } else if (gso_type == VIRTIO_NET_HDR_GSO_TCPV6) { + /* Calculate IP pseudo header checksum */ + cntr = eth_calc_ip6_pseudo_hdr_csum(ip_hdr, pkt->payload_len, + IP_PROTO_TCP, &cso); + csum = cpu_to_be16(~net_checksum_finish(cntr)); + } else { + return; + } + + iov_from_buf(&pkt->vec[NET_TX_PKT_PL_START_FRAG], pkt->payload_frags, + pkt->virt_hdr.csum_offset, &csum, sizeof(csum)); +} + +static void net_tx_pkt_calculate_hdr_len(struct NetTxPkt *pkt) +{ + pkt->hdr_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len + + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; +} + +static bool net_tx_pkt_parse_headers(struct NetTxPkt *pkt) +{ + struct iovec *l2_hdr, *l3_hdr; + size_t bytes_read; + size_t full_ip6hdr_len; + uint16_t l3_proto; + + assert(pkt); + + l2_hdr = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; + l3_hdr = &pkt->vec[NET_TX_PKT_L3HDR_FRAG]; + + bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, 0, l2_hdr->iov_base, + ETH_MAX_L2_HDR_LEN); + if (bytes_read < sizeof(struct eth_header)) { + l2_hdr->iov_len = 0; + return false; + } + + l2_hdr->iov_len = sizeof(struct eth_header); + switch (be16_to_cpu(PKT_GET_ETH_HDR(l2_hdr->iov_base)->h_proto)) { + case ETH_P_VLAN: + l2_hdr->iov_len += sizeof(struct vlan_header); + break; + case ETH_P_DVLAN: + l2_hdr->iov_len += 2 * sizeof(struct vlan_header); + break; + } + + if (bytes_read < l2_hdr->iov_len) { + l2_hdr->iov_len = 0; + l3_hdr->iov_len = 0; + pkt->packet_type = ETH_PKT_UCAST; + return false; + } else { + l2_hdr->iov_len = ETH_MAX_L2_HDR_LEN; + l2_hdr->iov_len = eth_get_l2_hdr_length(l2_hdr->iov_base); + pkt->packet_type = get_eth_packet_type(l2_hdr->iov_base); + } + + l3_proto = eth_get_l3_proto(l2_hdr, 1, l2_hdr->iov_len); + + switch (l3_proto) { + case ETH_P_IP: + bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, + l3_hdr->iov_base, sizeof(struct ip_header)); + + if (bytes_read < sizeof(struct ip_header)) { + l3_hdr->iov_len = 0; + return false; + } + + l3_hdr->iov_len = IP_HDR_GET_LEN(l3_hdr->iov_base); + + if (l3_hdr->iov_len < sizeof(struct ip_header)) { + l3_hdr->iov_len = 0; + return false; + } + + pkt->l4proto = ((struct ip_header *) l3_hdr->iov_base)->ip_p; + + if (IP_HDR_GET_LEN(l3_hdr->iov_base) != sizeof(struct ip_header)) { + /* copy optional IPv4 header data if any*/ + bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, + l2_hdr->iov_len + sizeof(struct ip_header), + l3_hdr->iov_base + sizeof(struct ip_header), + l3_hdr->iov_len - sizeof(struct ip_header)); + if (bytes_read < l3_hdr->iov_len - sizeof(struct ip_header)) { + l3_hdr->iov_len = 0; + return false; + } + } + + break; + + case ETH_P_IPV6: + { + eth_ip6_hdr_info hdrinfo; + + if (!eth_parse_ipv6_hdr(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, + &hdrinfo)) { + l3_hdr->iov_len = 0; + return false; + } + + pkt->l4proto = hdrinfo.l4proto; + full_ip6hdr_len = hdrinfo.full_hdr_len; + + if (full_ip6hdr_len > ETH_MAX_IP_DGRAM_LEN) { + l3_hdr->iov_len = 0; + return false; + } + + bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, + l3_hdr->iov_base, full_ip6hdr_len); + + if (bytes_read < full_ip6hdr_len) { + l3_hdr->iov_len = 0; + return false; + } else { + l3_hdr->iov_len = full_ip6hdr_len; + } + break; + } + default: + l3_hdr->iov_len = 0; + break; + } + + net_tx_pkt_calculate_hdr_len(pkt); + return true; +} + +static void net_tx_pkt_rebuild_payload(struct NetTxPkt *pkt) +{ + pkt->payload_len = iov_size(pkt->raw, pkt->raw_frags) - pkt->hdr_len; + pkt->payload_frags = iov_copy(&pkt->vec[NET_TX_PKT_PL_START_FRAG], + pkt->max_payload_frags, + pkt->raw, pkt->raw_frags, + pkt->hdr_len, pkt->payload_len); +} + +bool net_tx_pkt_parse(struct NetTxPkt *pkt) +{ + if (net_tx_pkt_parse_headers(pkt)) { + net_tx_pkt_rebuild_payload(pkt); + return true; + } else { + return false; + } +} + +struct virtio_net_hdr *net_tx_pkt_get_vhdr(struct NetTxPkt *pkt) +{ + assert(pkt); + return &pkt->virt_hdr; +} + +static uint8_t net_tx_pkt_get_gso_type(struct NetTxPkt *pkt, + bool tso_enable) +{ + uint8_t rc = VIRTIO_NET_HDR_GSO_NONE; + uint16_t l3_proto; + + l3_proto = eth_get_l3_proto(&pkt->vec[NET_TX_PKT_L2HDR_FRAG], 1, + pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len); + + if (!tso_enable) { + goto func_exit; + } + + rc = eth_get_gso_type(l3_proto, pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, + pkt->l4proto); + +func_exit: + return rc; +} + +void net_tx_pkt_build_vheader(struct NetTxPkt *pkt, bool tso_enable, + bool csum_enable, uint32_t gso_size) +{ + struct tcp_hdr l4hdr; + assert(pkt); + + /* csum has to be enabled if tso is. */ + assert(csum_enable || !tso_enable); + + pkt->virt_hdr.gso_type = net_tx_pkt_get_gso_type(pkt, tso_enable); + + switch (pkt->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { + case VIRTIO_NET_HDR_GSO_NONE: + pkt->virt_hdr.hdr_len = 0; + pkt->virt_hdr.gso_size = 0; + break; + + case VIRTIO_NET_HDR_GSO_UDP: + pkt->virt_hdr.gso_size = gso_size; + pkt->virt_hdr.hdr_len = pkt->hdr_len + sizeof(struct udp_header); + break; + + case VIRTIO_NET_HDR_GSO_TCPV4: + case VIRTIO_NET_HDR_GSO_TCPV6: + iov_to_buf(&pkt->vec[NET_TX_PKT_PL_START_FRAG], pkt->payload_frags, + 0, &l4hdr, sizeof(l4hdr)); + pkt->virt_hdr.hdr_len = pkt->hdr_len + l4hdr.th_off * sizeof(uint32_t); + pkt->virt_hdr.gso_size = gso_size; + break; + + default: + g_assert_not_reached(); + } + + if (csum_enable) { + switch (pkt->l4proto) { + case IP_PROTO_TCP: + pkt->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; + pkt->virt_hdr.csum_start = pkt->hdr_len; + pkt->virt_hdr.csum_offset = offsetof(struct tcp_hdr, th_sum); + break; + case IP_PROTO_UDP: + pkt->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; + pkt->virt_hdr.csum_start = pkt->hdr_len; + pkt->virt_hdr.csum_offset = offsetof(struct udp_hdr, uh_sum); + break; + default: + break; + } + } +} + +void net_tx_pkt_setup_vlan_header_ex(struct NetTxPkt *pkt, + uint16_t vlan, uint16_t vlan_ethtype) +{ + bool is_new; + assert(pkt); + + eth_setup_vlan_headers_ex(pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base, + vlan, vlan_ethtype, &is_new); + + /* update l2hdrlen */ + if (is_new) { + pkt->hdr_len += sizeof(struct vlan_header); + pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len += + sizeof(struct vlan_header); + } +} + +bool net_tx_pkt_add_raw_fragment(struct NetTxPkt *pkt, hwaddr pa, + size_t len) +{ + hwaddr mapped_len = 0; + struct iovec *ventry; + assert(pkt); + assert(pkt->max_raw_frags > pkt->raw_frags); + + if (!len) { + return true; + } + + ventry = &pkt->raw[pkt->raw_frags]; + mapped_len = len; + + ventry->iov_base = pci_dma_map(pkt->pci_dev, pa, + &mapped_len, DMA_DIRECTION_TO_DEVICE); + + if ((ventry->iov_base != NULL) && (len == mapped_len)) { + ventry->iov_len = mapped_len; + pkt->raw_frags++; + return true; + } else { + return false; + } +} + +bool net_tx_pkt_has_fragments(struct NetTxPkt *pkt) +{ + return pkt->raw_frags > 0; +} + +eth_pkt_types_e net_tx_pkt_get_packet_type(struct NetTxPkt *pkt) +{ + assert(pkt); + + return pkt->packet_type; +} + +size_t net_tx_pkt_get_total_len(struct NetTxPkt *pkt) +{ + assert(pkt); + + return pkt->hdr_len + pkt->payload_len; +} + +void net_tx_pkt_dump(struct NetTxPkt *pkt) +{ +#ifdef NET_TX_PKT_DEBUG + assert(pkt); + + printf("TX PKT: hdr_len: %d, pkt_type: 0x%X, l2hdr_len: %lu, " + "l3hdr_len: %lu, payload_len: %u\n", pkt->hdr_len, pkt->packet_type, + pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len, + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len, pkt->payload_len); +#endif +} + +void net_tx_pkt_reset(struct NetTxPkt *pkt) +{ + int i; + + /* no assert, as reset can be called before tx_pkt_init */ + if (!pkt) { + return; + } + + memset(&pkt->virt_hdr, 0, sizeof(pkt->virt_hdr)); + + assert(pkt->vec); + + pkt->payload_len = 0; + pkt->payload_frags = 0; + + assert(pkt->raw); + for (i = 0; i < pkt->raw_frags; i++) { + assert(pkt->raw[i].iov_base); + pci_dma_unmap(pkt->pci_dev, pkt->raw[i].iov_base, pkt->raw[i].iov_len, + DMA_DIRECTION_TO_DEVICE, 0); + } + pkt->raw_frags = 0; + + pkt->hdr_len = 0; + pkt->l4proto = 0; +} + +static void net_tx_pkt_do_sw_csum(struct NetTxPkt *pkt) +{ + struct iovec *iov = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; + uint32_t csum_cntr; + uint16_t csum = 0; + uint32_t cso; + /* num of iovec without vhdr */ + uint32_t iov_len = pkt->payload_frags + NET_TX_PKT_PL_START_FRAG - 1; + uint16_t csl; + struct ip_header *iphdr; + size_t csum_offset = pkt->virt_hdr.csum_start + pkt->virt_hdr.csum_offset; + + /* Put zero to checksum field */ + iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); + + /* Calculate L4 TCP/UDP checksum */ + csl = pkt->payload_len; + + /* add pseudo header to csum */ + iphdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; + csum_cntr = eth_calc_ip4_pseudo_hdr_csum(iphdr, csl, &cso); + + /* data checksum */ + csum_cntr += + net_checksum_add_iov(iov, iov_len, pkt->virt_hdr.csum_start, csl, cso); + + /* Put the checksum obtained into the packet */ + csum = cpu_to_be16(net_checksum_finish(csum_cntr)); + iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); +} + +enum { + NET_TX_PKT_FRAGMENT_L2_HDR_POS = 0, + NET_TX_PKT_FRAGMENT_L3_HDR_POS, + NET_TX_PKT_FRAGMENT_HEADER_NUM +}; + +#define NET_MAX_FRAG_SG_LIST (64) + +static size_t net_tx_pkt_fetch_fragment(struct NetTxPkt *pkt, + int *src_idx, size_t *src_offset, struct iovec *dst, int *dst_idx) +{ + size_t fetched = 0; + struct iovec *src = pkt->vec; + + *dst_idx = NET_TX_PKT_FRAGMENT_HEADER_NUM; + + while (fetched < IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size)) { + + /* no more place in fragment iov */ + if (*dst_idx == NET_MAX_FRAG_SG_LIST) { + break; + } + + /* no more data in iovec */ + if (*src_idx == (pkt->payload_frags + NET_TX_PKT_PL_START_FRAG)) { + break; + } + + + dst[*dst_idx].iov_base = src[*src_idx].iov_base + *src_offset; + dst[*dst_idx].iov_len = MIN(src[*src_idx].iov_len - *src_offset, + IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size) - fetched); + + *src_offset += dst[*dst_idx].iov_len; + fetched += dst[*dst_idx].iov_len; + + if (*src_offset == src[*src_idx].iov_len) { + *src_offset = 0; + (*src_idx)++; + } + + (*dst_idx)++; + } + + return fetched; +} + +static inline void net_tx_pkt_sendv(struct NetTxPkt *pkt, + NetClientState *nc, const struct iovec *iov, int iov_cnt) +{ + if (pkt->is_loopback) { + nc->info->receive_iov(nc, iov, iov_cnt); + } else { + qemu_sendv_packet(nc, iov, iov_cnt); + } +} + +static bool net_tx_pkt_do_sw_fragmentation(struct NetTxPkt *pkt, + NetClientState *nc) +{ + struct iovec fragment[NET_MAX_FRAG_SG_LIST]; + size_t fragment_len = 0; + bool more_frags = false; + + /* some pointers for shorter code */ + void *l2_iov_base, *l3_iov_base; + size_t l2_iov_len, l3_iov_len; + int src_idx = NET_TX_PKT_PL_START_FRAG, dst_idx; + size_t src_offset = 0; + size_t fragment_offset = 0; + + l2_iov_base = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base; + l2_iov_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len; + l3_iov_base = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; + l3_iov_len = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; + + /* Copy headers */ + fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_base = l2_iov_base; + fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_len = l2_iov_len; + fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_base = l3_iov_base; + fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_len = l3_iov_len; + + + /* Put as much data as possible and send */ + do { + fragment_len = net_tx_pkt_fetch_fragment(pkt, &src_idx, &src_offset, + fragment, &dst_idx); + + more_frags = (fragment_offset + fragment_len < pkt->payload_len); + + eth_setup_ip4_fragmentation(l2_iov_base, l2_iov_len, l3_iov_base, + l3_iov_len, fragment_len, fragment_offset, more_frags); + + eth_fix_ip4_checksum(l3_iov_base, l3_iov_len); + + net_tx_pkt_sendv(pkt, nc, fragment, dst_idx); + + fragment_offset += fragment_len; + + } while (more_frags); + + return true; +} + +bool net_tx_pkt_send(struct NetTxPkt *pkt, NetClientState *nc) +{ + assert(pkt); + + if (!pkt->has_virt_hdr && + pkt->virt_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { + net_tx_pkt_do_sw_csum(pkt); + } + + /* + * Since underlying infrastructure does not support IP datagrams longer + * than 64K we should drop such packets and don't even try to send + */ + if (VIRTIO_NET_HDR_GSO_NONE != pkt->virt_hdr.gso_type) { + if (pkt->payload_len > + ETH_MAX_IP_DGRAM_LEN - + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len) { + return false; + } + } + + if (pkt->has_virt_hdr || + pkt->virt_hdr.gso_type == VIRTIO_NET_HDR_GSO_NONE) { + net_tx_pkt_sendv(pkt, nc, pkt->vec, + pkt->payload_frags + NET_TX_PKT_PL_START_FRAG); + return true; + } + + return net_tx_pkt_do_sw_fragmentation(pkt, nc); +} + +bool net_tx_pkt_send_loopback(struct NetTxPkt *pkt, NetClientState *nc) +{ + bool res; + + pkt->is_loopback = true; + res = net_tx_pkt_send(pkt, nc); + pkt->is_loopback = false; + + return res; +} |