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 (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 (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 (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 | assert(pkt->max_raw_frags > pkt->raw_frags); |
383 | |
384 | if (!len) { |
385 | return true; |
386 | } |
387 | |
388 | ventry = &pkt->raw[pkt->raw_frags]; |
389 | mapped_len = len; |
390 | |
391 | ventry->iov_base = pci_dma_map(pkt->pci_dev, pa, |
392 | &mapped_len, DMA_DIRECTION_TO_DEVICE); |
393 | |
394 | if ((ventry->iov_base != NULL) && (len == mapped_len)) { |
395 | ventry->iov_len = mapped_len; |
396 | pkt->raw_frags++; |
397 | return true; |
398 | } else { |
399 | return false; |
400 | } |
401 | } |
402 | |
403 | bool net_tx_pkt_has_fragments(struct NetTxPkt *pkt) |
404 | { |
405 | return pkt->raw_frags > 0; |
406 | } |
407 | |
408 | eth_pkt_types_e net_tx_pkt_get_packet_type(struct NetTxPkt *pkt) |
409 | { |
410 | assert(pkt); |
411 | |
412 | return pkt->packet_type; |
413 | } |
414 | |
415 | size_t net_tx_pkt_get_total_len(struct NetTxPkt *pkt) |
416 | { |
417 | assert(pkt); |
418 | |
419 | return pkt->hdr_len + pkt->payload_len; |
420 | } |
421 | |
422 | void net_tx_pkt_dump(struct NetTxPkt *pkt) |
423 | { |
424 | #ifdef NET_TX_PKT_DEBUG |
425 | assert(pkt); |
426 | |
427 | printf("TX PKT: hdr_len: %d, pkt_type: 0x%X, l2hdr_len: %lu, " |
428 | "l3hdr_len: %lu, payload_len: %u\n" , pkt->hdr_len, pkt->packet_type, |
429 | pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len, |
430 | pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len, pkt->payload_len); |
431 | #endif |
432 | } |
433 | |
434 | void net_tx_pkt_reset(struct NetTxPkt *pkt) |
435 | { |
436 | int i; |
437 | |
438 | /* no assert, as reset can be called before tx_pkt_init */ |
439 | if (!pkt) { |
440 | return; |
441 | } |
442 | |
443 | memset(&pkt->virt_hdr, 0, sizeof(pkt->virt_hdr)); |
444 | |
445 | assert(pkt->vec); |
446 | |
447 | pkt->payload_len = 0; |
448 | pkt->payload_frags = 0; |
449 | |
450 | assert(pkt->raw); |
451 | for (i = 0; i < pkt->raw_frags; i++) { |
452 | assert(pkt->raw[i].iov_base); |
453 | pci_dma_unmap(pkt->pci_dev, pkt->raw[i].iov_base, pkt->raw[i].iov_len, |
454 | DMA_DIRECTION_TO_DEVICE, 0); |
455 | } |
456 | pkt->raw_frags = 0; |
457 | |
458 | pkt->hdr_len = 0; |
459 | pkt->l4proto = 0; |
460 | } |
461 | |
462 | static void net_tx_pkt_do_sw_csum(struct NetTxPkt *pkt) |
463 | { |
464 | struct iovec *iov = &pkt->vec[NET_TX_PKT_L2HDR_FRAG]; |
465 | uint32_t csum_cntr; |
466 | uint16_t csum = 0; |
467 | uint32_t cso; |
468 | /* num of iovec without vhdr */ |
469 | uint32_t iov_len = pkt->payload_frags + NET_TX_PKT_PL_START_FRAG - 1; |
470 | uint16_t csl; |
471 | struct ip_header *iphdr; |
472 | size_t csum_offset = pkt->virt_hdr.csum_start + pkt->virt_hdr.csum_offset; |
473 | |
474 | /* Put zero to checksum field */ |
475 | iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); |
476 | |
477 | /* Calculate L4 TCP/UDP checksum */ |
478 | csl = pkt->payload_len; |
479 | |
480 | /* add pseudo header to csum */ |
481 | iphdr = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; |
482 | csum_cntr = eth_calc_ip4_pseudo_hdr_csum(iphdr, csl, &cso); |
483 | |
484 | /* data checksum */ |
485 | csum_cntr += |
486 | net_checksum_add_iov(iov, iov_len, pkt->virt_hdr.csum_start, csl, cso); |
487 | |
488 | /* Put the checksum obtained into the packet */ |
489 | csum = cpu_to_be16(net_checksum_finish_nozero(csum_cntr)); |
490 | iov_from_buf(iov, iov_len, csum_offset, &csum, sizeof csum); |
491 | } |
492 | |
493 | enum { |
494 | NET_TX_PKT_FRAGMENT_L2_HDR_POS = 0, |
495 | NET_TX_PKT_FRAGMENT_L3_HDR_POS, |
496 | |
497 | }; |
498 | |
499 | #define NET_MAX_FRAG_SG_LIST (64) |
500 | |
501 | static size_t net_tx_pkt_fetch_fragment(struct NetTxPkt *pkt, |
502 | int *src_idx, size_t *src_offset, struct iovec *dst, int *dst_idx) |
503 | { |
504 | size_t fetched = 0; |
505 | struct iovec *src = pkt->vec; |
506 | |
507 | *dst_idx = NET_TX_PKT_FRAGMENT_HEADER_NUM; |
508 | |
509 | while (fetched < IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size)) { |
510 | |
511 | /* no more place in fragment iov */ |
512 | if (*dst_idx == NET_MAX_FRAG_SG_LIST) { |
513 | break; |
514 | } |
515 | |
516 | /* no more data in iovec */ |
517 | if (*src_idx == (pkt->payload_frags + NET_TX_PKT_PL_START_FRAG)) { |
518 | break; |
519 | } |
520 | |
521 | |
522 | dst[*dst_idx].iov_base = src[*src_idx].iov_base + *src_offset; |
523 | dst[*dst_idx].iov_len = MIN(src[*src_idx].iov_len - *src_offset, |
524 | IP_FRAG_ALIGN_SIZE(pkt->virt_hdr.gso_size) - fetched); |
525 | |
526 | *src_offset += dst[*dst_idx].iov_len; |
527 | fetched += dst[*dst_idx].iov_len; |
528 | |
529 | if (*src_offset == src[*src_idx].iov_len) { |
530 | *src_offset = 0; |
531 | (*src_idx)++; |
532 | } |
533 | |
534 | (*dst_idx)++; |
535 | } |
536 | |
537 | return fetched; |
538 | } |
539 | |
540 | static inline void net_tx_pkt_sendv(struct NetTxPkt *pkt, |
541 | NetClientState *nc, const struct iovec *iov, int iov_cnt) |
542 | { |
543 | if (pkt->is_loopback) { |
544 | nc->info->receive_iov(nc, iov, iov_cnt); |
545 | } else { |
546 | qemu_sendv_packet(nc, iov, iov_cnt); |
547 | } |
548 | } |
549 | |
550 | static bool net_tx_pkt_do_sw_fragmentation(struct NetTxPkt *pkt, |
551 | NetClientState *nc) |
552 | { |
553 | struct iovec fragment[NET_MAX_FRAG_SG_LIST]; |
554 | size_t fragment_len = 0; |
555 | bool more_frags = false; |
556 | |
557 | /* some pointers for shorter code */ |
558 | void *l2_iov_base, *l3_iov_base; |
559 | size_t l2_iov_len, l3_iov_len; |
560 | int src_idx = NET_TX_PKT_PL_START_FRAG, dst_idx; |
561 | size_t src_offset = 0; |
562 | size_t fragment_offset = 0; |
563 | |
564 | l2_iov_base = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_base; |
565 | l2_iov_len = pkt->vec[NET_TX_PKT_L2HDR_FRAG].iov_len; |
566 | l3_iov_base = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_base; |
567 | l3_iov_len = pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len; |
568 | |
569 | /* Copy headers */ |
570 | fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_base = l2_iov_base; |
571 | fragment[NET_TX_PKT_FRAGMENT_L2_HDR_POS].iov_len = l2_iov_len; |
572 | fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_base = l3_iov_base; |
573 | fragment[NET_TX_PKT_FRAGMENT_L3_HDR_POS].iov_len = l3_iov_len; |
574 | |
575 | |
576 | /* Put as much data as possible and send */ |
577 | do { |
578 | fragment_len = net_tx_pkt_fetch_fragment(pkt, &src_idx, &src_offset, |
579 | fragment, &dst_idx); |
580 | |
581 | more_frags = (fragment_offset + fragment_len < pkt->payload_len); |
582 | |
583 | eth_setup_ip4_fragmentation(l2_iov_base, l2_iov_len, l3_iov_base, |
584 | l3_iov_len, fragment_len, fragment_offset, more_frags); |
585 | |
586 | eth_fix_ip4_checksum(l3_iov_base, l3_iov_len); |
587 | |
588 | net_tx_pkt_sendv(pkt, nc, fragment, dst_idx); |
589 | |
590 | fragment_offset += fragment_len; |
591 | |
592 | } while (fragment_len && more_frags); |
593 | |
594 | return true; |
595 | } |
596 | |
597 | bool net_tx_pkt_send(struct NetTxPkt *pkt, NetClientState *nc) |
598 | { |
599 | assert(pkt); |
600 | |
601 | if (!pkt->has_virt_hdr && |
602 | pkt->virt_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) { |
603 | net_tx_pkt_do_sw_csum(pkt); |
604 | } |
605 | |
606 | /* |
607 | * Since underlying infrastructure does not support IP datagrams longer |
608 | * than 64K we should drop such packets and don't even try to send |
609 | */ |
610 | if (VIRTIO_NET_HDR_GSO_NONE != pkt->virt_hdr.gso_type) { |
611 | if (pkt->payload_len > |
612 | ETH_MAX_IP_DGRAM_LEN - |
613 | pkt->vec[NET_TX_PKT_L3HDR_FRAG].iov_len) { |
614 | return false; |
615 | } |
616 | } |
617 | |
618 | if (pkt->has_virt_hdr || |
619 | pkt->virt_hdr.gso_type == VIRTIO_NET_HDR_GSO_NONE) { |
620 | net_tx_pkt_sendv(pkt, nc, pkt->vec, |
621 | pkt->payload_frags + NET_TX_PKT_PL_START_FRAG); |
622 | return true; |
623 | } |
624 | |
625 | return net_tx_pkt_do_sw_fragmentation(pkt, nc); |
626 | } |
627 | |
628 | bool net_tx_pkt_send_loopback(struct NetTxPkt *pkt, NetClientState *nc) |
629 | { |
630 | bool res; |
631 | |
632 | pkt->is_loopback = true; |
633 | res = net_tx_pkt_send(pkt, nc); |
634 | pkt->is_loopback = false; |
635 | |
636 | return res; |
637 | } |
638 | |