meson: convert qapi-specific to meson
[qemu.git] / hw / net / net_tx_pkt.c
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 }