1 /* 2 * QEMU TX packets abstractions 3 * 4 * Copyright (c) 2012 Ravello Systems LTD (http://ravellosystems.com) 5 * 6 * Developed by Daynix Computing LTD (http://www.daynix.com) 7 * 8 * Authors: 9 * Dmitry Fleytman <dmitry@daynix.com> 10 * Tamir Shomer <tamirs@daynix.com> 11 * Yan Vugenfirer <yan@daynix.com> 12 * 13 * This work is licensed under the terms of the GNU GPL, version 2 or later. 14 * See the COPYING file in the top-level directory. 15 * 16 */ 17 18 #include "qemu/osdep.h" 19 #include "net_tx_pkt.h" 20 #include "net/eth.h" 21 #include "net/checksum.h" 22 #include "net/tap.h" 23 #include "net/net.h" 24 #include "hw/pci/pci.h" 25 26 enum { 27 NET_TX_PKT_VHDR_FRAG = 0, 28 NET_TX_PKT_L2HDR_FRAG, 29 NET_TX_PKT_L3HDR_FRAG, 30 NET_TX_PKT_PL_START_FRAG 31 }; 32 33 /* TX packet private context */ 34 struct NetTxPkt { 35 PCIDevice *pci_dev; 36 37 struct virtio_net_hdr virt_hdr; 38 bool has_virt_hdr; 39 40 struct iovec *raw; 41 uint32_t raw_frags; 42 uint32_t max_raw_frags; 43 44 struct iovec *vec; 45 46 uint8_t l2_hdr[ETH_MAX_L2_HDR_LEN]; 47 uint8_t l3_hdr[ETH_MAX_IP_DGRAM_LEN]; 48 49 uint32_t payload_len; 50 51 uint32_t payload_frags; 52 uint32_t max_payload_frags; 53 54 uint16_t hdr_len; 55 eth_pkt_types_e packet_type; 56 uint8_t l4proto; 57 58 bool is_loopback; 59 }; 60 61 void net_tx_pkt_init(struct NetTxPkt **pkt, PCIDevice *pci_dev, 62 uint32_t max_frags, bool has_virt_hdr) 63 { 64 struct NetTxPkt *p = g_malloc0(sizeof *p); 65 66 p->pci_dev = pci_dev; 67 68 p->vec = g_new(struct iovec, max_frags + NET_TX_PKT_PL_START_FRAG); 69 70 p->raw = g_new(struct iovec, max_frags); 71 72 p->max_payload_frags = max_frags; 73 p->max_raw_frags = max_frags; 74 p->has_virt_hdr = has_virt_hdr; 75 p->vec[NET_TX_PKT_VHDR_FRAG].iov_base = &p->virt_hdr; 76 p->vec[NET_TX_PKT_VHDR_FRAG].iov_len = 77 p->has_virt_hdr ? sizeof p->virt_hdr : 0; 78 p->vec[NET_TX_PKT_L2HDR_FRAG].iov_base = &p->l2_hdr; 79 p->vec[NET_TX_PKT_L3HDR_FRAG].iov_base = &p->l3_hdr; 80 81 *pkt = p; 82 } 83 84 void net_tx_pkt_uninit(struct NetTxPkt *pkt) 85 { 86 if (pkt) { 87 g_free(pkt->vec); 88 g_free(pkt->raw); 89 g_free(pkt); 90 } 91 } 92 93 void net_tx_pkt_update_ip_hdr_checksum(struct NetTxPkt *pkt) 94 { 95 uint16_t csum; 96 assert(pkt); 97 struct ip_header *ip_hdr; 98 ip_hdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; 99 100 ip_hdr->ip_len = cpu_to_be16(pkt->payload_len + 101 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len); 102 103 ip_hdr->ip_sum = 0; 104 csum = net_raw_checksum((uint8_t *)ip_hdr, 105 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len); 106 ip_hdr->ip_sum = cpu_to_be16(csum); 107 } 108 109 void net_tx_pkt_update_ip_checksums(struct NetTxPkt *pkt) 110 { 111 uint16_t csum; 112 uint32_t cntr, cso; 113 assert(pkt); 114 uint8_t gso_type = pkt->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN; 115 void *ip_hdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; 116 117 if (pkt->payload_len + pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len > 118 ETH_MAX_IP_DGRAM_LEN) { 119 return; 120 } 121 122 if (gso_type == VIRTIO_NET_HDR_GSO_TCPV4 || 123 gso_type == VIRTIO_NET_HDR_GSO_UDP) { 124 /* Calculate IP header checksum */ 125 net_tx_pkt_update_ip_hdr_checksum(pkt); 126 127 /* Calculate IP pseudo header checksum */ 128 cntr = eth_calc_ip4_pseudo_hdr_csum(ip_hdr, pkt->payload_len, &cso); 129 csum = cpu_to_be16(~net_checksum_finish(cntr)); 130 } else if (gso_type == VIRTIO_NET_HDR_GSO_TCPV6) { 131 /* Calculate IP pseudo header checksum */ 132 cntr = eth_calc_ip6_pseudo_hdr_csum(ip_hdr, pkt->payload_len, 133 IP_PROTO_TCP, &cso); 134 csum = cpu_to_be16(~net_checksum_finish(cntr)); 135 } else { 136 return; 137 } 138 139 iov_from_buf(&pkt->vec[NET_TX_PKT_PL_START_FRAG], pkt->payload_frags, 140 pkt->virt_hdr.csum_offset, &csum, sizeof(csum)); 141 } 142 143 static void net_tx_pkt_calculate_hdr_len(struct NetTxPkt *pkt) 144 { 145 pkt->hdr_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len + 146 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; 147 } 148 149 static bool net_tx_pkt_parse_headers(struct NetTxPkt *pkt) 150 { 151 struct iovec *l2_hdr, *l3_hdr; 152 size_t bytes_read; 153 size_t full_ip6hdr_len; 154 uint16_t l3_proto; 155 156 assert(pkt); 157 158 l2_hdr = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; 159 l3_hdr = &pkt->vec[NET_TX_PKT_L3HDR_FRAG]; 160 161 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, 0, l2_hdr->iov_base, 162 ETH_MAX_L2_HDR_LEN); 163 if (bytes_read < sizeof(struct eth_header)) { 164 l2_hdr->iov_len = 0; 165 return false; 166 } 167 168 l2_hdr->iov_len = sizeof(struct eth_header); 169 switch (be16_to_cpu(PKT_GET_ETH_HDR(l2_hdr->iov_base)->h_proto)) { 170 case ETH_P_VLAN: 171 l2_hdr->iov_len += sizeof(struct vlan_header); 172 break; 173 case ETH_P_DVLAN: 174 l2_hdr->iov_len += 2 * sizeof(struct vlan_header); 175 break; 176 } 177 178 if (bytes_read < l2_hdr->iov_len) { 179 l2_hdr->iov_len = 0; 180 l3_hdr->iov_len = 0; 181 pkt->packet_type = ETH_PKT_UCAST; 182 return false; 183 } else { 184 l2_hdr->iov_len = ETH_MAX_L2_HDR_LEN; 185 l2_hdr->iov_len = eth_get_l2_hdr_length(l2_hdr->iov_base); 186 pkt->packet_type = get_eth_packet_type(l2_hdr->iov_base); 187 } 188 189 l3_proto = eth_get_l3_proto(l2_hdr, 1, l2_hdr->iov_len); 190 191 switch (l3_proto) { 192 case ETH_P_IP: 193 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, 194 l3_hdr->iov_base, sizeof(struct ip_header)); 195 196 if (bytes_read < sizeof(struct ip_header)) { 197 l3_hdr->iov_len = 0; 198 return false; 199 } 200 201 l3_hdr->iov_len = IP_HDR_GET_LEN(l3_hdr->iov_base); 202 203 if (l3_hdr->iov_len < sizeof(struct ip_header)) { 204 l3_hdr->iov_len = 0; 205 return false; 206 } 207 208 pkt->l4proto = IP_HDR_GET_P(l3_hdr->iov_base); 209 210 if (IP_HDR_GET_LEN(l3_hdr->iov_base) != sizeof(struct ip_header)) { 211 /* copy optional IPv4 header data if any*/ 212 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, 213 l2_hdr->iov_len + sizeof(struct ip_header), 214 l3_hdr->iov_base + sizeof(struct ip_header), 215 l3_hdr->iov_len - sizeof(struct ip_header)); 216 if (bytes_read < l3_hdr->iov_len - sizeof(struct ip_header)) { 217 l3_hdr->iov_len = 0; 218 return false; 219 } 220 } 221 222 break; 223 224 case ETH_P_IPV6: 225 { 226 eth_ip6_hdr_info hdrinfo; 227 228 if (!eth_parse_ipv6_hdr(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, 229 &hdrinfo)) { 230 l3_hdr->iov_len = 0; 231 return false; 232 } 233 234 pkt->l4proto = hdrinfo.l4proto; 235 full_ip6hdr_len = hdrinfo.full_hdr_len; 236 237 if (full_ip6hdr_len > ETH_MAX_IP_DGRAM_LEN) { 238 l3_hdr->iov_len = 0; 239 return false; 240 } 241 242 bytes_read = iov_to_buf(pkt->raw, pkt->raw_frags, l2_hdr->iov_len, 243 l3_hdr->iov_base, full_ip6hdr_len); 244 245 if (bytes_read < full_ip6hdr_len) { 246 l3_hdr->iov_len = 0; 247 return false; 248 } else { 249 l3_hdr->iov_len = full_ip6hdr_len; 250 } 251 break; 252 } 253 default: 254 l3_hdr->iov_len = 0; 255 break; 256 } 257 258 net_tx_pkt_calculate_hdr_len(pkt); 259 return true; 260 } 261 262 static void net_tx_pkt_rebuild_payload(struct NetTxPkt *pkt) 263 { 264 pkt->payload_len = iov_size(pkt->raw, pkt->raw_frags) - pkt->hdr_len; 265 pkt->payload_frags = iov_copy(&pkt->vec[NET_TX_PKT_PL_START_FRAG], 266 pkt->max_payload_frags, 267 pkt->raw, pkt->raw_frags, 268 pkt->hdr_len, pkt->payload_len); 269 } 270 271 bool net_tx_pkt_parse(struct NetTxPkt *pkt) 272 { 273 if (net_tx_pkt_parse_headers(pkt)) { 274 net_tx_pkt_rebuild_payload(pkt); 275 return true; 276 } else { 277 return false; 278 } 279 } 280 281 struct virtio_net_hdr *net_tx_pkt_get_vhdr(struct NetTxPkt *pkt) 282 { 283 assert(pkt); 284 return &pkt->virt_hdr; 285 } 286 287 static uint8_t net_tx_pkt_get_gso_type(struct NetTxPkt *pkt, 288 bool tso_enable) 289 { 290 uint8_t rc = VIRTIO_NET_HDR_GSO_NONE; 291 uint16_t l3_proto; 292 293 l3_proto = eth_get_l3_proto(&pkt->vec[NET_TX_PKT_L2HDR_FRAG], 1, 294 pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len); 295 296 if (!tso_enable) { 297 goto func_exit; 298 } 299 300 rc = eth_get_gso_type(l3_proto, pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, 301 pkt->l4proto); 302 303 func_exit: 304 return rc; 305 } 306 307 void net_tx_pkt_build_vheader(struct NetTxPkt *pkt, bool tso_enable, 308 bool csum_enable, uint32_t gso_size) 309 { 310 struct tcp_hdr l4hdr; 311 assert(pkt); 312 313 /* csum has to be enabled if tso is. */ 314 assert(csum_enable || !tso_enable); 315 316 pkt->virt_hdr.gso_type = net_tx_pkt_get_gso_type(pkt, tso_enable); 317 318 switch (pkt->virt_hdr.gso_type & ~VIRTIO_NET_HDR_GSO_ECN) { 319 case VIRTIO_NET_HDR_GSO_NONE: 320 pkt->virt_hdr.hdr_len = 0; 321 pkt->virt_hdr.gso_size = 0; 322 break; 323 324 case VIRTIO_NET_HDR_GSO_UDP: 325 pkt->virt_hdr.gso_size = gso_size; 326 pkt->virt_hdr.hdr_len = pkt->hdr_len + sizeof(struct udp_header); 327 break; 328 329 case VIRTIO_NET_HDR_GSO_TCPV4: 330 case VIRTIO_NET_HDR_GSO_TCPV6: 331 iov_to_buf(&pkt->vec[NET_TX_PKT_PL_START_FRAG], pkt->payload_frags, 332 0, &l4hdr, sizeof(l4hdr)); 333 pkt->virt_hdr.hdr_len = pkt->hdr_len + l4hdr.th_off * sizeof(uint32_t); 334 pkt->virt_hdr.gso_size = gso_size; 335 break; 336 337 default: 338 g_assert_not_reached(); 339 } 340 341 if (csum_enable) { 342 switch (pkt->l4proto) { 343 case IP_PROTO_TCP: 344 pkt->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 345 pkt->virt_hdr.csum_start = pkt->hdr_len; 346 pkt->virt_hdr.csum_offset = offsetof(struct tcp_hdr, th_sum); 347 break; 348 case IP_PROTO_UDP: 349 pkt->virt_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 350 pkt->virt_hdr.csum_start = pkt->hdr_len; 351 pkt->virt_hdr.csum_offset = offsetof(struct udp_hdr, uh_sum); 352 break; 353 default: 354 break; 355 } 356 } 357 } 358 359 void net_tx_pkt_setup_vlan_header_ex(struct NetTxPkt *pkt, 360 uint16_t vlan, uint16_t vlan_ethtype) 361 { 362 bool is_new; 363 assert(pkt); 364 365 eth_setup_vlan_headers_ex(pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base, 366 vlan, vlan_ethtype, &is_new); 367 368 /* update l2hdrlen */ 369 if (is_new) { 370 pkt->hdr_len += sizeof(struct vlan_header); 371 pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len += 372 sizeof(struct vlan_header); 373 } 374 } 375 376 bool net_tx_pkt_add_raw_fragment(struct NetTxPkt *pkt, hwaddr pa, 377 size_t len) 378 { 379 hwaddr mapped_len = 0; 380 struct iovec *ventry; 381 assert(pkt); 382 383 if (pkt->raw_frags >= pkt->max_raw_frags) { 384 return false; 385 } 386 387 if (!len) { 388 return true; 389 } 390 391 ventry = &pkt->raw[pkt->raw_frags]; 392 mapped_len = len; 393 394 ventry->iov_base = pci_dma_map(pkt->pci_dev, pa, 395 &mapped_len, DMA_DIRECTION_TO_DEVICE); 396 397 if ((ventry->iov_base != NULL) && (len == mapped_len)) { 398 ventry->iov_len = mapped_len; 399 pkt->raw_frags++; 400 return true; 401 } else { 402 return false; 403 } 404 } 405 406 bool net_tx_pkt_has_fragments(struct NetTxPkt *pkt) 407 { 408 return pkt->raw_frags > 0; 409 } 410 411 eth_pkt_types_e net_tx_pkt_get_packet_type(struct NetTxPkt *pkt) 412 { 413 assert(pkt); 414 415 return pkt->packet_type; 416 } 417 418 size_t net_tx_pkt_get_total_len(struct NetTxPkt *pkt) 419 { 420 assert(pkt); 421 422 return pkt->hdr_len + pkt->payload_len; 423 } 424 425 void net_tx_pkt_dump(struct NetTxPkt *pkt) 426 { 427 #ifdef NET_TX_PKT_DEBUG 428 assert(pkt); 429 430 printf("TX PKT: hdr_len: %d, pkt_type: 0x%X, l2hdr_len: %lu, " 431 "l3hdr_len: %lu, payload_len: %u\n", pkt->hdr_len, pkt->packet_type, 432 pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len, 433 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len, pkt->payload_len); 434 #endif 435 } 436 437 void net_tx_pkt_reset(struct NetTxPkt *pkt) 438 { 439 int i; 440 441 /* no assert, as reset can be called before tx_pkt_init */ 442 if (!pkt) { 443 return; 444 } 445 446 memset(&pkt->virt_hdr, 0, sizeof(pkt->virt_hdr)); 447 448 assert(pkt->vec); 449 450 pkt->payload_len = 0; 451 pkt->payload_frags = 0; 452 453 assert(pkt->raw); 454 for (i = 0; i < pkt->raw_frags; i++) { 455 assert(pkt->raw[i].iov_base); 456 pci_dma_unmap(pkt->pci_dev, pkt->raw[i].iov_base, pkt->raw[i].iov_len, 457 DMA_DIRECTION_TO_DEVICE, 0); 458 } 459 pkt->raw_frags = 0; 460 461 pkt->hdr_len = 0; 462 pkt->l4proto = 0; 463 } 464 465 static void net_tx_pkt_do_sw_csum(struct NetTxPkt *pkt) 466 { 467 struct iovec *iov = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; 468 uint32_t csum_cntr; 469 uint16_t csum = 0; 470 uint32_t cso; 471 /* num of iovec without vhdr */ 472 uint32_t iov_len = pkt->payload_frags + NET_TX_PKT_PL_START_FRAG - 1; 473 uint16_t csl; 474 size_t csum_offset = pkt->virt_hdr.csum_start + pkt->virt_hdr.csum_offset; 475 uint16_t l3_proto = eth_get_l3_proto(iov, 1, iov->iov_len); 476 477 /* Put zero to checksum field */ 478 iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); 479 480 /* Calculate L4 TCP/UDP checksum */ 481 csl = pkt->payload_len; 482 483 csum_cntr = 0; 484 cso = 0; 485 /* add pseudo header to csum */ 486 if (l3_proto == ETH_P_IP) { 487 csum_cntr = eth_calc_ip4_pseudo_hdr_csum( 488 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, 489 csl, &cso); 490 } else if (l3_proto == ETH_P_IPV6) { 491 csum_cntr = eth_calc_ip6_pseudo_hdr_csum( 492 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base, 493 csl, pkt->l4proto, &cso); 494 } 495 496 /* data checksum */ 497 csum_cntr += 498 net_checksum_add_iov(iov, iov_len, pkt->virt_hdr.csum_start, csl, cso); 499 500 /* Put the checksum obtained into the packet */ 501 csum = cpu_to_be16(net_checksum_finish_nozero(csum_cntr)); 502 iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); 503 } 504 505 enum { 506 NET_TX_PKT_FRAGMENT_L2_HDR_POS = 0, 507 NET_TX_PKT_FRAGMENT_L3_HDR_POS, 508 NET_TX_PKT_FRAGMENT_HEADER_NUM 509 }; 510 511 #define NET_MAX_FRAG_SG_LIST (64) 512 513 static size_t net_tx_pkt_fetch_fragment(struct NetTxPkt *pkt, 514 int *src_idx, size_t *src_offset, struct iovec *dst, int *dst_idx) 515 { 516 size_t fetched = 0; 517 struct iovec *src = pkt->vec; 518 519 *dst_idx = NET_TX_PKT_FRAGMENT_HEADER_NUM; 520 521 while (fetched < IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size)) { 522 523 /* no more place in fragment iov */ 524 if (*dst_idx == NET_MAX_FRAG_SG_LIST) { 525 break; 526 } 527 528 /* no more data in iovec */ 529 if (*src_idx == (pkt->payload_frags + NET_TX_PKT_PL_START_FRAG)) { 530 break; 531 } 532 533 534 dst[*dst_idx].iov_base = src[*src_idx].iov_base + *src_offset; 535 dst[*dst_idx].iov_len = MIN(src[*src_idx].iov_len - *src_offset, 536 IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size) - fetched); 537 538 *src_offset += dst[*dst_idx].iov_len; 539 fetched += dst[*dst_idx].iov_len; 540 541 if (*src_offset == src[*src_idx].iov_len) { 542 *src_offset = 0; 543 (*src_idx)++; 544 } 545 546 (*dst_idx)++; 547 } 548 549 return fetched; 550 } 551 552 static inline void net_tx_pkt_sendv(struct NetTxPkt *pkt, 553 NetClientState *nc, const struct iovec *iov, int iov_cnt) 554 { 555 if (pkt->is_loopback) { 556 nc->info->receive_iov(nc, iov, iov_cnt); 557 } else { 558 qemu_sendv_packet(nc, iov, iov_cnt); 559 } 560 } 561 562 static bool net_tx_pkt_do_sw_fragmentation(struct NetTxPkt *pkt, 563 NetClientState *nc) 564 { 565 struct iovec fragment[NET_MAX_FRAG_SG_LIST]; 566 size_t fragment_len = 0; 567 bool more_frags = false; 568 569 /* some pointers for shorter code */ 570 void *l2_iov_base, *l3_iov_base; 571 size_t l2_iov_len, l3_iov_len; 572 int src_idx = NET_TX_PKT_PL_START_FRAG, dst_idx; 573 size_t src_offset = 0; 574 size_t fragment_offset = 0; 575 576 l2_iov_base = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base; 577 l2_iov_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len; 578 l3_iov_base = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; 579 l3_iov_len = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; 580 581 /* Copy headers */ 582 fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_base = l2_iov_base; 583 fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_len = l2_iov_len; 584 fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_base = l3_iov_base; 585 fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_len = l3_iov_len; 586 587 588 /* Put as much data as possible and send */ 589 do { 590 fragment_len = net_tx_pkt_fetch_fragment(pkt, &src_idx, &src_offset, 591 fragment, &dst_idx); 592 593 more_frags = (fragment_offset + fragment_len < pkt->payload_len); 594 595 eth_setup_ip4_fragmentation(l2_iov_base, l2_iov_len, l3_iov_base, 596 l3_iov_len, fragment_len, fragment_offset, more_frags); 597 598 eth_fix_ip4_checksum(l3_iov_base, l3_iov_len); 599 600 net_tx_pkt_sendv(pkt, nc, fragment, dst_idx); 601 602 fragment_offset += fragment_len; 603 604 } while (fragment_len && more_frags); 605 606 return true; 607 } 608 609 bool net_tx_pkt_send(struct NetTxPkt *pkt, NetClientState *nc) 610 { 611 assert(pkt); 612 613 if (!pkt->has_virt_hdr && 614 pkt->virt_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { 615 net_tx_pkt_do_sw_csum(pkt); 616 } 617 618 /* 619 * Since underlying infrastructure does not support IP datagrams longer 620 * than 64K we should drop such packets and don't even try to send 621 */ 622 if (VIRTIO_NET_HDR_GSO_NONE != pkt->virt_hdr.gso_type) { 623 if (pkt->payload_len > 624 ETH_MAX_IP_DGRAM_LEN - 625 pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len) { 626 return false; 627 } 628 } 629 630 if (pkt->has_virt_hdr || 631 pkt->virt_hdr.gso_type == VIRTIO_NET_HDR_GSO_NONE) { 632 net_tx_pkt_fix_ip6_payload_len(pkt); 633 net_tx_pkt_sendv(pkt, nc, pkt->vec, 634 pkt->payload_frags + NET_TX_PKT_PL_START_FRAG); 635 return true; 636 } 637 638 return net_tx_pkt_do_sw_fragmentation(pkt, nc); 639 } 640 641 bool net_tx_pkt_send_loopback(struct NetTxPkt *pkt, NetClientState *nc) 642 { 643 bool res; 644 645 pkt->is_loopback = true; 646 res = net_tx_pkt_send(pkt, nc); 647 pkt->is_loopback = false; 648 649 return res; 650 } 651 652 void net_tx_pkt_fix_ip6_payload_len(struct NetTxPkt *pkt) 653 { 654 struct iovec *l2 = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; 655 if (eth_get_l3_proto(l2, 1, l2->iov_len) == ETH_P_IPV6) { 656 struct ip6_header *ip6 = (struct ip6_header *) pkt->l3_hdr; 657 /* 658 * TODO: if qemu would support >64K packets - add jumbo option check 659 * something like that: 660 * 'if (ip6->ip6_plen == 0 && !has_jumbo_option(ip6)) {' 661 */ 662 if (ip6->ip6_plen == 0) { 663 if (pkt->payload_len <= ETH_MAX_IP_DGRAM_LEN) { 664 ip6->ip6_plen = htons(pkt->payload_len); 665 } 666 /* 667 * TODO: if qemu would support >64K packets 668 * add jumbo option for packets greater then 65,535 bytes 669 */ 670 } 671 } 672 } 673