xref: /dpdk/app/test-pmd/csumonly.c (revision f8dbaebbf1c9efcbb2e2354b341ed62175466a57)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation.
3  * Copyright 2014 6WIND S.A.
4  */
5 
6 #include <stdarg.h>
7 #include <stdio.h>
8 #include <errno.h>
9 #include <stdint.h>
10 #include <unistd.h>
11 #include <inttypes.h>
12 
13 #include <sys/queue.h>
14 #include <sys/stat.h>
15 
16 #include <rte_common.h>
17 #include <rte_byteorder.h>
18 #include <rte_log.h>
19 #include <rte_debug.h>
20 #include <rte_cycles.h>
21 #include <rte_memory.h>
22 #include <rte_memcpy.h>
23 #include <rte_launch.h>
24 #include <rte_eal.h>
25 #include <rte_per_lcore.h>
26 #include <rte_lcore.h>
27 #include <rte_branch_prediction.h>
28 #include <rte_mempool.h>
29 #include <rte_mbuf.h>
30 #include <rte_interrupts.h>
31 #include <rte_pci.h>
32 #include <rte_ether.h>
33 #include <rte_ethdev.h>
34 #include <rte_ip.h>
35 #include <rte_tcp.h>
36 #include <rte_udp.h>
37 #include <rte_vxlan.h>
38 #include <rte_sctp.h>
39 #include <rte_gtp.h>
40 #include <rte_prefetch.h>
41 #include <rte_string_fns.h>
42 #include <rte_flow.h>
43 #ifdef RTE_LIB_GRO
44 #include <rte_gro.h>
45 #endif
46 #ifdef RTE_LIB_GSO
47 #include <rte_gso.h>
48 #endif
49 #include <rte_geneve.h>
50 
51 #include "testpmd.h"
52 
53 #define IP_DEFTTL  64   /* from RFC 1340. */
54 
55 #define GRE_CHECKSUM_PRESENT	0x8000
56 #define GRE_KEY_PRESENT		0x2000
57 #define GRE_SEQUENCE_PRESENT	0x1000
58 #define GRE_EXT_LEN		4
59 #define GRE_SUPPORTED_FIELDS	(GRE_CHECKSUM_PRESENT | GRE_KEY_PRESENT |\
60 				 GRE_SEQUENCE_PRESENT)
61 
62 /* We cannot use rte_cpu_to_be_16() on a constant in a switch/case */
63 #if RTE_BYTE_ORDER == RTE_LITTLE_ENDIAN
64 #define _htons(x) ((uint16_t)((((x) & 0x00ffU) << 8) | (((x) & 0xff00U) >> 8)))
65 #else
66 #define _htons(x) (x)
67 #endif
68 
69 uint16_t vxlan_gpe_udp_port = RTE_VXLAN_GPE_DEFAULT_PORT;
70 uint16_t geneve_udp_port = RTE_GENEVE_DEFAULT_PORT;
71 
72 /* structure that caches offload info for the current packet */
73 struct testpmd_offload_info {
74 	uint16_t ethertype;
75 #ifdef RTE_LIB_GSO
76 	uint8_t gso_enable;
77 #endif
78 	uint16_t l2_len;
79 	uint16_t l3_len;
80 	uint16_t l4_len;
81 	uint8_t l4_proto;
82 	uint8_t is_tunnel;
83 	uint16_t outer_ethertype;
84 	uint16_t outer_l2_len;
85 	uint16_t outer_l3_len;
86 	uint8_t outer_l4_proto;
87 	uint16_t tso_segsz;
88 	uint16_t tunnel_tso_segsz;
89 	uint32_t pkt_len;
90 };
91 
92 /* simplified GRE header */
93 struct simple_gre_hdr {
94 	uint16_t flags;
95 	uint16_t proto;
96 } __rte_packed;
97 
98 static uint16_t
99 get_udptcp_checksum(void *l3_hdr, void *l4_hdr, uint16_t ethertype)
100 {
101 	if (ethertype == _htons(RTE_ETHER_TYPE_IPV4))
102 		return rte_ipv4_udptcp_cksum(l3_hdr, l4_hdr);
103 	else /* assume ethertype == RTE_ETHER_TYPE_IPV6 */
104 		return rte_ipv6_udptcp_cksum(l3_hdr, l4_hdr);
105 }
106 
107 /* Parse an IPv4 header to fill l3_len, l4_len, and l4_proto */
108 static void
109 parse_ipv4(struct rte_ipv4_hdr *ipv4_hdr, struct testpmd_offload_info *info)
110 {
111 	struct rte_tcp_hdr *tcp_hdr;
112 
113 	info->l3_len = rte_ipv4_hdr_len(ipv4_hdr);
114 	info->l4_proto = ipv4_hdr->next_proto_id;
115 
116 	/* only fill l4_len for TCP, it's useful for TSO */
117 	if (info->l4_proto == IPPROTO_TCP) {
118 		tcp_hdr = (struct rte_tcp_hdr *)
119 			((char *)ipv4_hdr + info->l3_len);
120 		info->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
121 	} else if (info->l4_proto == IPPROTO_UDP)
122 		info->l4_len = sizeof(struct rte_udp_hdr);
123 	else
124 		info->l4_len = 0;
125 }
126 
127 /* Parse an IPv6 header to fill l3_len, l4_len, and l4_proto */
128 static void
129 parse_ipv6(struct rte_ipv6_hdr *ipv6_hdr, struct testpmd_offload_info *info)
130 {
131 	struct rte_tcp_hdr *tcp_hdr;
132 
133 	info->l3_len = sizeof(struct rte_ipv6_hdr);
134 	info->l4_proto = ipv6_hdr->proto;
135 
136 	/* only fill l4_len for TCP, it's useful for TSO */
137 	if (info->l4_proto == IPPROTO_TCP) {
138 		tcp_hdr = (struct rte_tcp_hdr *)
139 			((char *)ipv6_hdr + info->l3_len);
140 		info->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
141 	} else if (info->l4_proto == IPPROTO_UDP)
142 		info->l4_len = sizeof(struct rte_udp_hdr);
143 	else
144 		info->l4_len = 0;
145 }
146 
147 /*
148  * Parse an ethernet header to fill the ethertype, l2_len, l3_len and
149  * ipproto. This function is able to recognize IPv4/IPv6 with optional VLAN
150  * headers. The l4_len argument is only set in case of TCP (useful for TSO).
151  */
152 static void
153 parse_ethernet(struct rte_ether_hdr *eth_hdr, struct testpmd_offload_info *info)
154 {
155 	struct rte_ipv4_hdr *ipv4_hdr;
156 	struct rte_ipv6_hdr *ipv6_hdr;
157 	struct rte_vlan_hdr *vlan_hdr;
158 
159 	info->l2_len = sizeof(struct rte_ether_hdr);
160 	info->ethertype = eth_hdr->ether_type;
161 
162 	while (info->ethertype == _htons(RTE_ETHER_TYPE_VLAN) ||
163 	       info->ethertype == _htons(RTE_ETHER_TYPE_QINQ)) {
164 		vlan_hdr = (struct rte_vlan_hdr *)
165 			((char *)eth_hdr + info->l2_len);
166 		info->l2_len  += sizeof(struct rte_vlan_hdr);
167 		info->ethertype = vlan_hdr->eth_proto;
168 	}
169 
170 	switch (info->ethertype) {
171 	case _htons(RTE_ETHER_TYPE_IPV4):
172 		ipv4_hdr = (struct rte_ipv4_hdr *)
173 			((char *)eth_hdr + info->l2_len);
174 		parse_ipv4(ipv4_hdr, info);
175 		break;
176 	case _htons(RTE_ETHER_TYPE_IPV6):
177 		ipv6_hdr = (struct rte_ipv6_hdr *)
178 			((char *)eth_hdr + info->l2_len);
179 		parse_ipv6(ipv6_hdr, info);
180 		break;
181 	default:
182 		info->l4_len = 0;
183 		info->l3_len = 0;
184 		info->l4_proto = 0;
185 		break;
186 	}
187 }
188 
189 /* Fill in outer layers length */
190 static void
191 update_tunnel_outer(struct testpmd_offload_info *info)
192 {
193 	info->is_tunnel = 1;
194 	info->outer_ethertype = info->ethertype;
195 	info->outer_l2_len = info->l2_len;
196 	info->outer_l3_len = info->l3_len;
197 	info->outer_l4_proto = info->l4_proto;
198 }
199 
200 /*
201  * Parse a GTP protocol header.
202  * No optional fields and next extension header type.
203  */
204 static void
205 parse_gtp(struct rte_udp_hdr *udp_hdr,
206 	  struct testpmd_offload_info *info)
207 {
208 	struct rte_ipv4_hdr *ipv4_hdr;
209 	struct rte_ipv6_hdr *ipv6_hdr;
210 	struct rte_gtp_hdr *gtp_hdr;
211 	uint8_t gtp_len = sizeof(*gtp_hdr);
212 	uint8_t ip_ver;
213 
214 	/* Check udp destination port. */
215 	if (udp_hdr->dst_port != _htons(RTE_GTPC_UDP_PORT) &&
216 	    udp_hdr->src_port != _htons(RTE_GTPC_UDP_PORT) &&
217 	    udp_hdr->dst_port != _htons(RTE_GTPU_UDP_PORT))
218 		return;
219 
220 	update_tunnel_outer(info);
221 	info->l2_len = 0;
222 
223 	gtp_hdr = (struct rte_gtp_hdr *)((char *)udp_hdr +
224 		  sizeof(struct rte_udp_hdr));
225 
226 	/*
227 	 * Check message type. If message type is 0xff, it is
228 	 * a GTP data packet. If not, it is a GTP control packet
229 	 */
230 	if (gtp_hdr->msg_type == 0xff) {
231 		ip_ver = *(uint8_t *)((char *)udp_hdr +
232 			 sizeof(struct rte_udp_hdr) +
233 			 sizeof(struct rte_gtp_hdr));
234 		ip_ver = (ip_ver) & 0xf0;
235 
236 		if (ip_ver == RTE_GTP_TYPE_IPV4) {
237 			ipv4_hdr = (struct rte_ipv4_hdr *)((char *)gtp_hdr +
238 				   gtp_len);
239 			info->ethertype = _htons(RTE_ETHER_TYPE_IPV4);
240 			parse_ipv4(ipv4_hdr, info);
241 		} else if (ip_ver == RTE_GTP_TYPE_IPV6) {
242 			ipv6_hdr = (struct rte_ipv6_hdr *)((char *)gtp_hdr +
243 				   gtp_len);
244 			info->ethertype = _htons(RTE_ETHER_TYPE_IPV6);
245 			parse_ipv6(ipv6_hdr, info);
246 		}
247 	} else {
248 		info->ethertype = 0;
249 		info->l4_len = 0;
250 		info->l3_len = 0;
251 		info->l4_proto = 0;
252 	}
253 
254 	info->l2_len += RTE_ETHER_GTP_HLEN;
255 }
256 
257 /* Parse a vxlan header */
258 static void
259 parse_vxlan(struct rte_udp_hdr *udp_hdr,
260 	    struct testpmd_offload_info *info,
261 	    uint32_t pkt_type)
262 {
263 	struct rte_ether_hdr *eth_hdr;
264 
265 	/* check udp destination port, RTE_VXLAN_DEFAULT_PORT (4789) is the
266 	 * default vxlan port (rfc7348) or that the rx offload flag is set
267 	 * (i40e only currently)
268 	 */
269 	if (udp_hdr->dst_port != _htons(RTE_VXLAN_DEFAULT_PORT) &&
270 		RTE_ETH_IS_TUNNEL_PKT(pkt_type) == 0)
271 		return;
272 
273 	update_tunnel_outer(info);
274 
275 	eth_hdr = (struct rte_ether_hdr *)((char *)udp_hdr +
276 		sizeof(struct rte_udp_hdr) +
277 		sizeof(struct rte_vxlan_hdr));
278 
279 	parse_ethernet(eth_hdr, info);
280 	info->l2_len += RTE_ETHER_VXLAN_HLEN; /* add udp + vxlan */
281 }
282 
283 /* Parse a vxlan-gpe header */
284 static void
285 parse_vxlan_gpe(struct rte_udp_hdr *udp_hdr,
286 	    struct testpmd_offload_info *info)
287 {
288 	struct rte_ether_hdr *eth_hdr;
289 	struct rte_ipv4_hdr *ipv4_hdr;
290 	struct rte_ipv6_hdr *ipv6_hdr;
291 	struct rte_vxlan_gpe_hdr *vxlan_gpe_hdr;
292 	uint8_t vxlan_gpe_len = sizeof(*vxlan_gpe_hdr);
293 
294 	/* Check udp destination port. */
295 	if (udp_hdr->dst_port != _htons(vxlan_gpe_udp_port))
296 		return;
297 
298 	vxlan_gpe_hdr = (struct rte_vxlan_gpe_hdr *)((char *)udp_hdr +
299 				sizeof(struct rte_udp_hdr));
300 
301 	if (!vxlan_gpe_hdr->proto || vxlan_gpe_hdr->proto ==
302 	    RTE_VXLAN_GPE_TYPE_IPV4) {
303 		update_tunnel_outer(info);
304 
305 		ipv4_hdr = (struct rte_ipv4_hdr *)((char *)vxlan_gpe_hdr +
306 			   vxlan_gpe_len);
307 
308 		parse_ipv4(ipv4_hdr, info);
309 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV4);
310 		info->l2_len = 0;
311 
312 	} else if (vxlan_gpe_hdr->proto == RTE_VXLAN_GPE_TYPE_IPV6) {
313 		update_tunnel_outer(info);
314 
315 		ipv6_hdr = (struct rte_ipv6_hdr *)((char *)vxlan_gpe_hdr +
316 			   vxlan_gpe_len);
317 
318 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV6);
319 		parse_ipv6(ipv6_hdr, info);
320 		info->l2_len = 0;
321 
322 	} else if (vxlan_gpe_hdr->proto == RTE_VXLAN_GPE_TYPE_ETH) {
323 		update_tunnel_outer(info);
324 
325 		eth_hdr = (struct rte_ether_hdr *)((char *)vxlan_gpe_hdr +
326 			  vxlan_gpe_len);
327 
328 		parse_ethernet(eth_hdr, info);
329 	} else
330 		return;
331 
332 	info->l2_len += RTE_ETHER_VXLAN_GPE_HLEN;
333 }
334 
335 /* Parse a geneve header */
336 static void
337 parse_geneve(struct rte_udp_hdr *udp_hdr,
338 	    struct testpmd_offload_info *info)
339 {
340 	struct rte_ether_hdr *eth_hdr;
341 	struct rte_ipv4_hdr *ipv4_hdr;
342 	struct rte_ipv6_hdr *ipv6_hdr;
343 	struct rte_geneve_hdr *geneve_hdr;
344 	uint16_t geneve_len;
345 
346 	/* Check udp destination port. */
347 	if (udp_hdr->dst_port != _htons(geneve_udp_port))
348 		return;
349 
350 	geneve_hdr = (struct rte_geneve_hdr *)((char *)udp_hdr +
351 				sizeof(struct rte_udp_hdr));
352 	geneve_len = sizeof(struct rte_geneve_hdr) + geneve_hdr->opt_len * 4;
353 	if (!geneve_hdr->proto || geneve_hdr->proto ==
354 	    _htons(RTE_ETHER_TYPE_IPV4)) {
355 		update_tunnel_outer(info);
356 		ipv4_hdr = (struct rte_ipv4_hdr *)((char *)geneve_hdr +
357 			   geneve_len);
358 		parse_ipv4(ipv4_hdr, info);
359 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV4);
360 		info->l2_len = 0;
361 	} else if (geneve_hdr->proto == _htons(RTE_ETHER_TYPE_IPV6)) {
362 		update_tunnel_outer(info);
363 		ipv6_hdr = (struct rte_ipv6_hdr *)((char *)geneve_hdr +
364 			   geneve_len);
365 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV6);
366 		parse_ipv6(ipv6_hdr, info);
367 		info->l2_len = 0;
368 
369 	} else if (geneve_hdr->proto == _htons(RTE_GENEVE_TYPE_ETH)) {
370 		update_tunnel_outer(info);
371 		eth_hdr = (struct rte_ether_hdr *)((char *)geneve_hdr +
372 			  geneve_len);
373 		parse_ethernet(eth_hdr, info);
374 	} else
375 		return;
376 
377 	info->l2_len +=
378 		(sizeof(struct rte_udp_hdr) + sizeof(struct rte_geneve_hdr) +
379 		((struct rte_geneve_hdr *)geneve_hdr)->opt_len * 4);
380 }
381 
382 /* Parse a gre header */
383 static void
384 parse_gre(struct simple_gre_hdr *gre_hdr, struct testpmd_offload_info *info)
385 {
386 	struct rte_ether_hdr *eth_hdr;
387 	struct rte_ipv4_hdr *ipv4_hdr;
388 	struct rte_ipv6_hdr *ipv6_hdr;
389 	uint8_t gre_len = 0;
390 
391 	gre_len += sizeof(struct simple_gre_hdr);
392 
393 	if (gre_hdr->flags & _htons(GRE_KEY_PRESENT))
394 		gre_len += GRE_EXT_LEN;
395 	if (gre_hdr->flags & _htons(GRE_SEQUENCE_PRESENT))
396 		gre_len += GRE_EXT_LEN;
397 	if (gre_hdr->flags & _htons(GRE_CHECKSUM_PRESENT))
398 		gre_len += GRE_EXT_LEN;
399 
400 	if (gre_hdr->proto == _htons(RTE_ETHER_TYPE_IPV4)) {
401 		update_tunnel_outer(info);
402 
403 		ipv4_hdr = (struct rte_ipv4_hdr *)((char *)gre_hdr + gre_len);
404 
405 		parse_ipv4(ipv4_hdr, info);
406 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV4);
407 		info->l2_len = 0;
408 
409 	} else if (gre_hdr->proto == _htons(RTE_ETHER_TYPE_IPV6)) {
410 		update_tunnel_outer(info);
411 
412 		ipv6_hdr = (struct rte_ipv6_hdr *)((char *)gre_hdr + gre_len);
413 
414 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV6);
415 		parse_ipv6(ipv6_hdr, info);
416 		info->l2_len = 0;
417 
418 	} else if (gre_hdr->proto == _htons(RTE_ETHER_TYPE_TEB)) {
419 		update_tunnel_outer(info);
420 
421 		eth_hdr = (struct rte_ether_hdr *)((char *)gre_hdr + gre_len);
422 
423 		parse_ethernet(eth_hdr, info);
424 	} else
425 		return;
426 
427 	info->l2_len += gre_len;
428 }
429 
430 
431 /* Parse an encapsulated ip or ipv6 header */
432 static void
433 parse_encap_ip(void *encap_ip, struct testpmd_offload_info *info)
434 {
435 	struct rte_ipv4_hdr *ipv4_hdr = encap_ip;
436 	struct rte_ipv6_hdr *ipv6_hdr = encap_ip;
437 	uint8_t ip_version;
438 
439 	ip_version = (ipv4_hdr->version_ihl & 0xf0) >> 4;
440 
441 	if (ip_version != 4 && ip_version != 6)
442 		return;
443 
444 	info->is_tunnel = 1;
445 	info->outer_ethertype = info->ethertype;
446 	info->outer_l2_len = info->l2_len;
447 	info->outer_l3_len = info->l3_len;
448 
449 	if (ip_version == 4) {
450 		parse_ipv4(ipv4_hdr, info);
451 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV4);
452 	} else {
453 		parse_ipv6(ipv6_hdr, info);
454 		info->ethertype = _htons(RTE_ETHER_TYPE_IPV6);
455 	}
456 	info->l2_len = 0;
457 }
458 
459 /* if possible, calculate the checksum of a packet in hw or sw,
460  * depending on the testpmd command line configuration */
461 static uint64_t
462 process_inner_cksums(void *l3_hdr, const struct testpmd_offload_info *info,
463 	uint64_t tx_offloads)
464 {
465 	struct rte_ipv4_hdr *ipv4_hdr = l3_hdr;
466 	struct rte_udp_hdr *udp_hdr;
467 	struct rte_tcp_hdr *tcp_hdr;
468 	struct rte_sctp_hdr *sctp_hdr;
469 	uint64_t ol_flags = 0;
470 	uint32_t max_pkt_len, tso_segsz = 0;
471 
472 	/* ensure packet is large enough to require tso */
473 	if (!info->is_tunnel) {
474 		max_pkt_len = info->l2_len + info->l3_len + info->l4_len +
475 			info->tso_segsz;
476 		if (info->tso_segsz != 0 && info->pkt_len > max_pkt_len)
477 			tso_segsz = info->tso_segsz;
478 	} else {
479 		max_pkt_len = info->outer_l2_len + info->outer_l3_len +
480 			info->l2_len + info->l3_len + info->l4_len +
481 			info->tunnel_tso_segsz;
482 		if (info->tunnel_tso_segsz != 0 && info->pkt_len > max_pkt_len)
483 			tso_segsz = info->tunnel_tso_segsz;
484 	}
485 
486 	if (info->ethertype == _htons(RTE_ETHER_TYPE_IPV4)) {
487 		ipv4_hdr = l3_hdr;
488 
489 		ol_flags |= RTE_MBUF_F_TX_IPV4;
490 		if (info->l4_proto == IPPROTO_TCP && tso_segsz) {
491 			ol_flags |= RTE_MBUF_F_TX_IP_CKSUM;
492 		} else {
493 			if (tx_offloads & RTE_ETH_TX_OFFLOAD_IPV4_CKSUM) {
494 				ol_flags |= RTE_MBUF_F_TX_IP_CKSUM;
495 			} else {
496 				ipv4_hdr->hdr_checksum = 0;
497 				ipv4_hdr->hdr_checksum =
498 					rte_ipv4_cksum(ipv4_hdr);
499 			}
500 		}
501 	} else if (info->ethertype == _htons(RTE_ETHER_TYPE_IPV6))
502 		ol_flags |= RTE_MBUF_F_TX_IPV6;
503 	else
504 		return 0; /* packet type not supported, nothing to do */
505 
506 	if (info->l4_proto == IPPROTO_UDP) {
507 		udp_hdr = (struct rte_udp_hdr *)((char *)l3_hdr + info->l3_len);
508 		/* do not recalculate udp cksum if it was 0 */
509 		if (udp_hdr->dgram_cksum != 0) {
510 			if (tx_offloads & RTE_ETH_TX_OFFLOAD_UDP_CKSUM) {
511 				ol_flags |= RTE_MBUF_F_TX_UDP_CKSUM;
512 			} else {
513 				udp_hdr->dgram_cksum = 0;
514 				udp_hdr->dgram_cksum =
515 					get_udptcp_checksum(l3_hdr, udp_hdr,
516 						info->ethertype);
517 			}
518 		}
519 #ifdef RTE_LIB_GSO
520 		if (info->gso_enable)
521 			ol_flags |= RTE_MBUF_F_TX_UDP_SEG;
522 #endif
523 	} else if (info->l4_proto == IPPROTO_TCP) {
524 		tcp_hdr = (struct rte_tcp_hdr *)((char *)l3_hdr + info->l3_len);
525 		if (tso_segsz)
526 			ol_flags |= RTE_MBUF_F_TX_TCP_SEG;
527 		else if (tx_offloads & RTE_ETH_TX_OFFLOAD_TCP_CKSUM) {
528 			ol_flags |= RTE_MBUF_F_TX_TCP_CKSUM;
529 		} else {
530 			tcp_hdr->cksum = 0;
531 			tcp_hdr->cksum =
532 				get_udptcp_checksum(l3_hdr, tcp_hdr,
533 					info->ethertype);
534 		}
535 #ifdef RTE_LIB_GSO
536 		if (info->gso_enable)
537 			ol_flags |= RTE_MBUF_F_TX_TCP_SEG;
538 #endif
539 	} else if (info->l4_proto == IPPROTO_SCTP) {
540 		sctp_hdr = (struct rte_sctp_hdr *)
541 			((char *)l3_hdr + info->l3_len);
542 		/* sctp payload must be a multiple of 4 to be
543 		 * offloaded */
544 		if ((tx_offloads & RTE_ETH_TX_OFFLOAD_SCTP_CKSUM) &&
545 			((ipv4_hdr->total_length & 0x3) == 0)) {
546 			ol_flags |= RTE_MBUF_F_TX_SCTP_CKSUM;
547 		} else {
548 			sctp_hdr->cksum = 0;
549 			/* XXX implement CRC32c, example available in
550 			 * RFC3309 */
551 		}
552 	}
553 
554 	return ol_flags;
555 }
556 
557 /* Calculate the checksum of outer header */
558 static uint64_t
559 process_outer_cksums(void *outer_l3_hdr, struct testpmd_offload_info *info,
560 	uint64_t tx_offloads, int tso_enabled)
561 {
562 	struct rte_ipv4_hdr *ipv4_hdr = outer_l3_hdr;
563 	struct rte_ipv6_hdr *ipv6_hdr = outer_l3_hdr;
564 	struct rte_udp_hdr *udp_hdr;
565 	uint64_t ol_flags = 0;
566 
567 	if (info->outer_ethertype == _htons(RTE_ETHER_TYPE_IPV4)) {
568 		ipv4_hdr->hdr_checksum = 0;
569 		ol_flags |= RTE_MBUF_F_TX_OUTER_IPV4;
570 
571 		if (tx_offloads	& RTE_ETH_TX_OFFLOAD_OUTER_IPV4_CKSUM)
572 			ol_flags |= RTE_MBUF_F_TX_OUTER_IP_CKSUM;
573 		else
574 			ipv4_hdr->hdr_checksum = rte_ipv4_cksum(ipv4_hdr);
575 	} else
576 		ol_flags |= RTE_MBUF_F_TX_OUTER_IPV6;
577 
578 	if (info->outer_l4_proto != IPPROTO_UDP)
579 		return ol_flags;
580 
581 	udp_hdr = (struct rte_udp_hdr *)
582 		((char *)outer_l3_hdr + info->outer_l3_len);
583 
584 	if (tso_enabled)
585 		ol_flags |= RTE_MBUF_F_TX_TCP_SEG;
586 
587 	/* Skip SW outer UDP checksum generation if HW supports it */
588 	if (tx_offloads & RTE_ETH_TX_OFFLOAD_OUTER_UDP_CKSUM) {
589 		if (info->outer_ethertype == _htons(RTE_ETHER_TYPE_IPV4))
590 			udp_hdr->dgram_cksum
591 				= rte_ipv4_phdr_cksum(ipv4_hdr, ol_flags);
592 		else
593 			udp_hdr->dgram_cksum
594 				= rte_ipv6_phdr_cksum(ipv6_hdr, ol_flags);
595 
596 		ol_flags |= RTE_MBUF_F_TX_OUTER_UDP_CKSUM;
597 		return ol_flags;
598 	}
599 
600 	/* outer UDP checksum is done in software. In the other side, for
601 	 * UDP tunneling, like VXLAN or Geneve, outer UDP checksum can be
602 	 * set to zero.
603 	 *
604 	 * If a packet will be TSOed into small packets by NIC, we cannot
605 	 * set/calculate a non-zero checksum, because it will be a wrong
606 	 * value after the packet be split into several small packets.
607 	 */
608 	if (tso_enabled)
609 		udp_hdr->dgram_cksum = 0;
610 
611 	/* do not recalculate udp cksum if it was 0 */
612 	if (udp_hdr->dgram_cksum != 0) {
613 		udp_hdr->dgram_cksum = 0;
614 		if (info->outer_ethertype == _htons(RTE_ETHER_TYPE_IPV4))
615 			udp_hdr->dgram_cksum =
616 				rte_ipv4_udptcp_cksum(ipv4_hdr, udp_hdr);
617 		else
618 			udp_hdr->dgram_cksum =
619 				rte_ipv6_udptcp_cksum(ipv6_hdr, udp_hdr);
620 	}
621 
622 	return ol_flags;
623 }
624 
625 /*
626  * Helper function.
627  * Performs actual copying.
628  * Returns number of segments in the destination mbuf on success,
629  * or negative error code on failure.
630  */
631 static int
632 mbuf_copy_split(const struct rte_mbuf *ms, struct rte_mbuf *md[],
633 	uint16_t seglen[], uint8_t nb_seg)
634 {
635 	uint32_t dlen, slen, tlen;
636 	uint32_t i, len;
637 	const struct rte_mbuf *m;
638 	const uint8_t *src;
639 	uint8_t *dst;
640 
641 	dlen = 0;
642 	slen = 0;
643 	tlen = 0;
644 
645 	dst = NULL;
646 	src = NULL;
647 
648 	m = ms;
649 	i = 0;
650 	while (ms != NULL && i != nb_seg) {
651 
652 		if (slen == 0) {
653 			slen = rte_pktmbuf_data_len(ms);
654 			src = rte_pktmbuf_mtod(ms, const uint8_t *);
655 		}
656 
657 		if (dlen == 0) {
658 			dlen = RTE_MIN(seglen[i], slen);
659 			md[i]->data_len = dlen;
660 			md[i]->next = (i + 1 == nb_seg) ? NULL : md[i + 1];
661 			dst = rte_pktmbuf_mtod(md[i], uint8_t *);
662 		}
663 
664 		len = RTE_MIN(slen, dlen);
665 		memcpy(dst, src, len);
666 		tlen += len;
667 		slen -= len;
668 		dlen -= len;
669 		src += len;
670 		dst += len;
671 
672 		if (slen == 0)
673 			ms = ms->next;
674 		if (dlen == 0)
675 			i++;
676 	}
677 
678 	if (ms != NULL)
679 		return -ENOBUFS;
680 	else if (tlen != m->pkt_len)
681 		return -EINVAL;
682 
683 	md[0]->nb_segs = nb_seg;
684 	md[0]->pkt_len = tlen;
685 	md[0]->vlan_tci = m->vlan_tci;
686 	md[0]->vlan_tci_outer = m->vlan_tci_outer;
687 	md[0]->ol_flags = m->ol_flags;
688 	md[0]->tx_offload = m->tx_offload;
689 
690 	return nb_seg;
691 }
692 
693 /*
694  * Allocate a new mbuf with up to tx_pkt_nb_segs segments.
695  * Copy packet contents and offload information into the new segmented mbuf.
696  */
697 static struct rte_mbuf *
698 pkt_copy_split(const struct rte_mbuf *pkt)
699 {
700 	int32_t n, rc;
701 	uint32_t i, len, nb_seg;
702 	struct rte_mempool *mp;
703 	uint16_t seglen[RTE_MAX_SEGS_PER_PKT];
704 	struct rte_mbuf *p, *md[RTE_MAX_SEGS_PER_PKT];
705 
706 	mp = current_fwd_lcore()->mbp;
707 
708 	if (tx_pkt_split == TX_PKT_SPLIT_RND)
709 		nb_seg = rte_rand() % tx_pkt_nb_segs + 1;
710 	else
711 		nb_seg = tx_pkt_nb_segs;
712 
713 	memcpy(seglen, tx_pkt_seg_lengths, nb_seg * sizeof(seglen[0]));
714 
715 	/* calculate number of segments to use and their length. */
716 	len = 0;
717 	for (i = 0; i != nb_seg && len < pkt->pkt_len; i++) {
718 		len += seglen[i];
719 		md[i] = NULL;
720 	}
721 
722 	n = pkt->pkt_len - len;
723 
724 	/* update size of the last segment to fit rest of the packet */
725 	if (n >= 0) {
726 		seglen[i - 1] += n;
727 		len += n;
728 	}
729 
730 	nb_seg = i;
731 	while (i != 0) {
732 		p = rte_pktmbuf_alloc(mp);
733 		if (p == NULL) {
734 			TESTPMD_LOG(ERR,
735 				"failed to allocate %u-th of %u mbuf "
736 				"from mempool: %s\n",
737 				nb_seg - i, nb_seg, mp->name);
738 			break;
739 		}
740 
741 		md[--i] = p;
742 		if (rte_pktmbuf_tailroom(md[i]) < seglen[i]) {
743 			TESTPMD_LOG(ERR, "mempool %s, %u-th segment: "
744 				"expected seglen: %u, "
745 				"actual mbuf tailroom: %u\n",
746 				mp->name, i, seglen[i],
747 				rte_pktmbuf_tailroom(md[i]));
748 			break;
749 		}
750 	}
751 
752 	/* all mbufs successfully allocated, do copy */
753 	if (i == 0) {
754 		rc = mbuf_copy_split(pkt, md, seglen, nb_seg);
755 		if (rc < 0)
756 			TESTPMD_LOG(ERR,
757 				"mbuf_copy_split for %p(len=%u, nb_seg=%u) "
758 				"into %u segments failed with error code: %d\n",
759 				pkt, pkt->pkt_len, pkt->nb_segs, nb_seg, rc);
760 
761 		/* figure out how many mbufs to free. */
762 		i = RTE_MAX(rc, 0);
763 	}
764 
765 	/* free unused mbufs */
766 	for (; i != nb_seg; i++) {
767 		rte_pktmbuf_free_seg(md[i]);
768 		md[i] = NULL;
769 	}
770 
771 	return md[0];
772 }
773 
774 /*
775  * Receive a burst of packets, and for each packet:
776  *  - parse packet, and try to recognize a supported packet type (1)
777  *  - if it's not a supported packet type, don't touch the packet, else:
778  *  - reprocess the checksum of all supported layers. This is done in SW
779  *    or HW, depending on testpmd command line configuration
780  *  - if TSO is enabled in testpmd command line, also flag the mbuf for TCP
781  *    segmentation offload (this implies HW TCP checksum)
782  * Then transmit packets on the output port.
783  *
784  * (1) Supported packets are:
785  *   Ether / (vlan) / IP|IP6 / UDP|TCP|SCTP .
786  *   Ether / (vlan) / outer IP|IP6 / outer UDP / VxLAN / Ether / IP|IP6 /
787  *           UDP|TCP|SCTP
788  *   Ether / (vlan) / outer IP|IP6 / outer UDP / VXLAN-GPE / Ether / IP|IP6 /
789  *           UDP|TCP|SCTP
790  *   Ether / (vlan) / outer IP|IP6 / outer UDP / VXLAN-GPE / IP|IP6 /
791  *           UDP|TCP|SCTP
792  *   Ether / (vlan) / outer IP / outer UDP / GTP / IP|IP6 / UDP|TCP|SCTP
793  *   Ether / (vlan) / outer IP|IP6 / GRE / Ether / IP|IP6 / UDP|TCP|SCTP
794  *   Ether / (vlan) / outer IP|IP6 / GRE / IP|IP6 / UDP|TCP|SCTP
795  *   Ether / (vlan) / outer IP|IP6 / IP|IP6 / UDP|TCP|SCTP
796  *
797  * The testpmd command line for this forward engine sets the flags
798  * TESTPMD_TX_OFFLOAD_* in ports[tx_port].tx_ol_flags. They control
799  * wether a checksum must be calculated in software or in hardware. The
800  * IP, UDP, TCP and SCTP flags always concern the inner layer. The
801  * OUTER_IP is only useful for tunnel packets.
802  */
803 static void
804 pkt_burst_checksum_forward(struct fwd_stream *fs)
805 {
806 	struct rte_mbuf *pkts_burst[MAX_PKT_BURST];
807 #ifdef RTE_LIB_GSO
808 	struct rte_mbuf *gso_segments[GSO_MAX_PKT_BURST];
809 	struct rte_gso_ctx *gso_ctx;
810 #endif
811 	struct rte_mbuf **tx_pkts_burst;
812 	struct rte_port *txp;
813 	struct rte_mbuf *m, *p;
814 	struct rte_ether_hdr *eth_hdr;
815 	void *l3_hdr = NULL, *outer_l3_hdr = NULL; /* can be IPv4 or IPv6 */
816 #ifdef RTE_LIB_GRO
817 	void **gro_ctx;
818 	uint16_t gro_pkts_num;
819 	uint8_t gro_enable;
820 #endif
821 	uint16_t nb_rx;
822 	uint16_t nb_tx;
823 	uint16_t nb_prep;
824 	uint16_t i;
825 	uint64_t rx_ol_flags, tx_ol_flags;
826 	uint64_t tx_offloads;
827 	uint32_t retry;
828 	uint32_t rx_bad_ip_csum;
829 	uint32_t rx_bad_l4_csum;
830 	uint32_t rx_bad_outer_l4_csum;
831 	uint32_t rx_bad_outer_ip_csum;
832 	struct testpmd_offload_info info;
833 
834 	uint64_t start_tsc = 0;
835 
836 	get_start_cycles(&start_tsc);
837 
838 	/* receive a burst of packet */
839 	nb_rx = rte_eth_rx_burst(fs->rx_port, fs->rx_queue, pkts_burst,
840 				 nb_pkt_per_burst);
841 	inc_rx_burst_stats(fs, nb_rx);
842 	if (unlikely(nb_rx == 0))
843 		return;
844 
845 	fs->rx_packets += nb_rx;
846 	rx_bad_ip_csum = 0;
847 	rx_bad_l4_csum = 0;
848 	rx_bad_outer_l4_csum = 0;
849 	rx_bad_outer_ip_csum = 0;
850 #ifdef RTE_LIB_GRO
851 	gro_enable = gro_ports[fs->rx_port].enable;
852 #endif
853 
854 	txp = &ports[fs->tx_port];
855 	tx_offloads = txp->dev_conf.txmode.offloads;
856 	memset(&info, 0, sizeof(info));
857 	info.tso_segsz = txp->tso_segsz;
858 	info.tunnel_tso_segsz = txp->tunnel_tso_segsz;
859 #ifdef RTE_LIB_GSO
860 	if (gso_ports[fs->tx_port].enable)
861 		info.gso_enable = 1;
862 #endif
863 
864 	for (i = 0; i < nb_rx; i++) {
865 		if (likely(i < nb_rx - 1))
866 			rte_prefetch0(rte_pktmbuf_mtod(pkts_burst[i + 1],
867 						       void *));
868 
869 		m = pkts_burst[i];
870 		info.is_tunnel = 0;
871 		info.pkt_len = rte_pktmbuf_pkt_len(m);
872 		tx_ol_flags = m->ol_flags &
873 			      (RTE_MBUF_F_INDIRECT | RTE_MBUF_F_EXTERNAL);
874 		rx_ol_flags = m->ol_flags;
875 
876 		/* Update the L3/L4 checksum error packet statistics */
877 		if ((rx_ol_flags & RTE_MBUF_F_RX_IP_CKSUM_MASK) == RTE_MBUF_F_RX_IP_CKSUM_BAD)
878 			rx_bad_ip_csum += 1;
879 		if ((rx_ol_flags & RTE_MBUF_F_RX_L4_CKSUM_MASK) == RTE_MBUF_F_RX_L4_CKSUM_BAD)
880 			rx_bad_l4_csum += 1;
881 		if (rx_ol_flags & RTE_MBUF_F_RX_OUTER_L4_CKSUM_BAD)
882 			rx_bad_outer_l4_csum += 1;
883 		if (rx_ol_flags & RTE_MBUF_F_RX_OUTER_IP_CKSUM_BAD)
884 			rx_bad_outer_ip_csum += 1;
885 
886 		/* step 1: dissect packet, parsing optional vlan, ip4/ip6, vxlan
887 		 * and inner headers */
888 
889 		eth_hdr = rte_pktmbuf_mtod(m, struct rte_ether_hdr *);
890 		rte_ether_addr_copy(&peer_eth_addrs[fs->peer_addr],
891 				&eth_hdr->dst_addr);
892 		rte_ether_addr_copy(&ports[fs->tx_port].eth_addr,
893 				&eth_hdr->src_addr);
894 		parse_ethernet(eth_hdr, &info);
895 		l3_hdr = (char *)eth_hdr + info.l2_len;
896 
897 		/* check if it's a supported tunnel */
898 		if (txp->parse_tunnel) {
899 			if (info.l4_proto == IPPROTO_UDP) {
900 				struct rte_udp_hdr *udp_hdr;
901 
902 				udp_hdr = (struct rte_udp_hdr *)
903 					((char *)l3_hdr + info.l3_len);
904 				parse_gtp(udp_hdr, &info);
905 				if (info.is_tunnel) {
906 					tx_ol_flags |= RTE_MBUF_F_TX_TUNNEL_GTP;
907 					goto tunnel_update;
908 				}
909 				parse_vxlan_gpe(udp_hdr, &info);
910 				if (info.is_tunnel) {
911 					tx_ol_flags |=
912 						RTE_MBUF_F_TX_TUNNEL_VXLAN_GPE;
913 					goto tunnel_update;
914 				}
915 				parse_vxlan(udp_hdr, &info,
916 					    m->packet_type);
917 				if (info.is_tunnel) {
918 					tx_ol_flags |=
919 						RTE_MBUF_F_TX_TUNNEL_VXLAN;
920 					goto tunnel_update;
921 				}
922 				parse_geneve(udp_hdr, &info);
923 				if (info.is_tunnel) {
924 					tx_ol_flags |=
925 						RTE_MBUF_F_TX_TUNNEL_GENEVE;
926 					goto tunnel_update;
927 				}
928 			} else if (info.l4_proto == IPPROTO_GRE) {
929 				struct simple_gre_hdr *gre_hdr;
930 
931 				gre_hdr = (struct simple_gre_hdr *)
932 					((char *)l3_hdr + info.l3_len);
933 				parse_gre(gre_hdr, &info);
934 				if (info.is_tunnel)
935 					tx_ol_flags |= RTE_MBUF_F_TX_TUNNEL_GRE;
936 			} else if (info.l4_proto == IPPROTO_IPIP) {
937 				void *encap_ip_hdr;
938 
939 				encap_ip_hdr = (char *)l3_hdr + info.l3_len;
940 				parse_encap_ip(encap_ip_hdr, &info);
941 				if (info.is_tunnel)
942 					tx_ol_flags |= RTE_MBUF_F_TX_TUNNEL_IPIP;
943 			}
944 		}
945 
946 tunnel_update:
947 		/* update l3_hdr and outer_l3_hdr if a tunnel was parsed */
948 		if (info.is_tunnel) {
949 			outer_l3_hdr = l3_hdr;
950 			l3_hdr = (char *)l3_hdr + info.outer_l3_len + info.l2_len;
951 		}
952 
953 		/* step 2: depending on user command line configuration,
954 		 * recompute checksum either in software or flag the
955 		 * mbuf to offload the calculation to the NIC. If TSO
956 		 * is configured, prepare the mbuf for TCP segmentation. */
957 
958 		/* process checksums of inner headers first */
959 		tx_ol_flags |= process_inner_cksums(l3_hdr, &info,
960 			tx_offloads);
961 
962 		/* Then process outer headers if any. Note that the software
963 		 * checksum will be wrong if one of the inner checksums is
964 		 * processed in hardware. */
965 		if (info.is_tunnel == 1) {
966 			tx_ol_flags |= process_outer_cksums(outer_l3_hdr, &info,
967 					tx_offloads,
968 					!!(tx_ol_flags & RTE_MBUF_F_TX_TCP_SEG));
969 		}
970 
971 		/* step 3: fill the mbuf meta data (flags and header lengths) */
972 
973 		m->tx_offload = 0;
974 		if (info.is_tunnel == 1) {
975 			if (info.tunnel_tso_segsz ||
976 			    (tx_offloads &
977 			     RTE_ETH_TX_OFFLOAD_OUTER_IPV4_CKSUM) ||
978 			    (tx_offloads &
979 			     RTE_ETH_TX_OFFLOAD_OUTER_UDP_CKSUM)) {
980 				m->outer_l2_len = info.outer_l2_len;
981 				m->outer_l3_len = info.outer_l3_len;
982 				m->l2_len = info.l2_len;
983 				m->l3_len = info.l3_len;
984 				m->l4_len = info.l4_len;
985 				m->tso_segsz = info.tunnel_tso_segsz;
986 			}
987 			else {
988 				/* if there is a outer UDP cksum
989 				   processed in sw and the inner in hw,
990 				   the outer checksum will be wrong as
991 				   the payload will be modified by the
992 				   hardware */
993 				m->l2_len = info.outer_l2_len +
994 					info.outer_l3_len + info.l2_len;
995 				m->l3_len = info.l3_len;
996 				m->l4_len = info.l4_len;
997 			}
998 		} else {
999 			/* this is only useful if an offload flag is
1000 			 * set, but it does not hurt to fill it in any
1001 			 * case */
1002 			m->l2_len = info.l2_len;
1003 			m->l3_len = info.l3_len;
1004 			m->l4_len = info.l4_len;
1005 			m->tso_segsz = info.tso_segsz;
1006 		}
1007 		m->ol_flags = tx_ol_flags;
1008 
1009 		/* Do split & copy for the packet. */
1010 		if (tx_pkt_split != TX_PKT_SPLIT_OFF) {
1011 			p = pkt_copy_split(m);
1012 			if (p != NULL) {
1013 				rte_pktmbuf_free(m);
1014 				m = p;
1015 				pkts_burst[i] = m;
1016 			}
1017 		}
1018 
1019 		/* if verbose mode is enabled, dump debug info */
1020 		if (verbose_level > 0) {
1021 			char buf[256];
1022 
1023 			printf("-----------------\n");
1024 			printf("port=%u, mbuf=%p, pkt_len=%u, nb_segs=%u:\n",
1025 				fs->rx_port, m, m->pkt_len, m->nb_segs);
1026 			/* dump rx parsed packet info */
1027 			rte_get_rx_ol_flag_list(rx_ol_flags, buf, sizeof(buf));
1028 			printf("rx: l2_len=%d ethertype=%x l3_len=%d "
1029 				"l4_proto=%d l4_len=%d flags=%s\n",
1030 				info.l2_len, rte_be_to_cpu_16(info.ethertype),
1031 				info.l3_len, info.l4_proto, info.l4_len, buf);
1032 			if (rx_ol_flags & RTE_MBUF_F_RX_LRO)
1033 				printf("rx: m->lro_segsz=%u\n", m->tso_segsz);
1034 			if (info.is_tunnel == 1)
1035 				printf("rx: outer_l2_len=%d outer_ethertype=%x "
1036 					"outer_l3_len=%d\n", info.outer_l2_len,
1037 					rte_be_to_cpu_16(info.outer_ethertype),
1038 					info.outer_l3_len);
1039 			/* dump tx packet info */
1040 			if ((tx_offloads & (RTE_ETH_TX_OFFLOAD_IPV4_CKSUM |
1041 					    RTE_ETH_TX_OFFLOAD_UDP_CKSUM |
1042 					    RTE_ETH_TX_OFFLOAD_TCP_CKSUM |
1043 					    RTE_ETH_TX_OFFLOAD_SCTP_CKSUM)) ||
1044 				info.tso_segsz != 0)
1045 				printf("tx: m->l2_len=%d m->l3_len=%d "
1046 					"m->l4_len=%d\n",
1047 					m->l2_len, m->l3_len, m->l4_len);
1048 			if (info.is_tunnel == 1) {
1049 				if ((tx_offloads &
1050 				    RTE_ETH_TX_OFFLOAD_OUTER_IPV4_CKSUM) ||
1051 				    (tx_offloads &
1052 				    RTE_ETH_TX_OFFLOAD_OUTER_UDP_CKSUM) ||
1053 				    (tx_ol_flags & RTE_MBUF_F_TX_OUTER_IPV6))
1054 					printf("tx: m->outer_l2_len=%d "
1055 						"m->outer_l3_len=%d\n",
1056 						m->outer_l2_len,
1057 						m->outer_l3_len);
1058 				if (info.tunnel_tso_segsz != 0 &&
1059 						(m->ol_flags & RTE_MBUF_F_TX_TCP_SEG))
1060 					printf("tx: m->tso_segsz=%d\n",
1061 						m->tso_segsz);
1062 			} else if (info.tso_segsz != 0 &&
1063 					(m->ol_flags & RTE_MBUF_F_TX_TCP_SEG))
1064 				printf("tx: m->tso_segsz=%d\n", m->tso_segsz);
1065 			rte_get_tx_ol_flag_list(m->ol_flags, buf, sizeof(buf));
1066 			printf("tx: flags=%s", buf);
1067 			printf("\n");
1068 		}
1069 	}
1070 
1071 #ifdef RTE_LIB_GRO
1072 	if (unlikely(gro_enable)) {
1073 		if (gro_flush_cycles == GRO_DEFAULT_FLUSH_CYCLES) {
1074 			nb_rx = rte_gro_reassemble_burst(pkts_burst, nb_rx,
1075 					&(gro_ports[fs->rx_port].param));
1076 		} else {
1077 			gro_ctx = current_fwd_lcore()->gro_ctx;
1078 			nb_rx = rte_gro_reassemble(pkts_burst, nb_rx, gro_ctx);
1079 
1080 			if (++fs->gro_times >= gro_flush_cycles) {
1081 				gro_pkts_num = rte_gro_get_pkt_count(gro_ctx);
1082 				if (gro_pkts_num > MAX_PKT_BURST - nb_rx)
1083 					gro_pkts_num = MAX_PKT_BURST - nb_rx;
1084 
1085 				nb_rx += rte_gro_timeout_flush(gro_ctx, 0,
1086 						RTE_GRO_TCP_IPV4,
1087 						&pkts_burst[nb_rx],
1088 						gro_pkts_num);
1089 				fs->gro_times = 0;
1090 			}
1091 		}
1092 	}
1093 #endif
1094 
1095 #ifdef RTE_LIB_GSO
1096 	if (gso_ports[fs->tx_port].enable != 0) {
1097 		uint16_t nb_segments = 0;
1098 
1099 		gso_ctx = &(current_fwd_lcore()->gso_ctx);
1100 		gso_ctx->gso_size = gso_max_segment_size;
1101 		for (i = 0; i < nb_rx; i++) {
1102 			int ret;
1103 
1104 			ret = rte_gso_segment(pkts_burst[i], gso_ctx,
1105 					&gso_segments[nb_segments],
1106 					GSO_MAX_PKT_BURST - nb_segments);
1107 			if (ret >= 1) {
1108 				/* pkts_burst[i] can be freed safely here. */
1109 				rte_pktmbuf_free(pkts_burst[i]);
1110 				nb_segments += ret;
1111 			} else if (ret == 0) {
1112 				/* 0 means it can be transmitted directly
1113 				 * without gso.
1114 				 */
1115 				gso_segments[nb_segments] = pkts_burst[i];
1116 				nb_segments += 1;
1117 			} else {
1118 				TESTPMD_LOG(DEBUG, "Unable to segment packet");
1119 				rte_pktmbuf_free(pkts_burst[i]);
1120 			}
1121 		}
1122 
1123 		tx_pkts_burst = gso_segments;
1124 		nb_rx = nb_segments;
1125 	} else
1126 #endif
1127 		tx_pkts_burst = pkts_burst;
1128 
1129 	nb_prep = rte_eth_tx_prepare(fs->tx_port, fs->tx_queue,
1130 			tx_pkts_burst, nb_rx);
1131 	if (nb_prep != nb_rx)
1132 		fprintf(stderr,
1133 			"Preparing packet burst to transmit failed: %s\n",
1134 			rte_strerror(rte_errno));
1135 
1136 	nb_tx = rte_eth_tx_burst(fs->tx_port, fs->tx_queue, tx_pkts_burst,
1137 			nb_prep);
1138 
1139 	/*
1140 	 * Retry if necessary
1141 	 */
1142 	if (unlikely(nb_tx < nb_rx) && fs->retry_enabled) {
1143 		retry = 0;
1144 		while (nb_tx < nb_rx && retry++ < burst_tx_retry_num) {
1145 			rte_delay_us(burst_tx_delay_time);
1146 			nb_tx += rte_eth_tx_burst(fs->tx_port, fs->tx_queue,
1147 					&tx_pkts_burst[nb_tx], nb_rx - nb_tx);
1148 		}
1149 	}
1150 	fs->tx_packets += nb_tx;
1151 	fs->rx_bad_ip_csum += rx_bad_ip_csum;
1152 	fs->rx_bad_l4_csum += rx_bad_l4_csum;
1153 	fs->rx_bad_outer_l4_csum += rx_bad_outer_l4_csum;
1154 	fs->rx_bad_outer_ip_csum += rx_bad_outer_ip_csum;
1155 
1156 	inc_tx_burst_stats(fs, nb_tx);
1157 	if (unlikely(nb_tx < nb_rx)) {
1158 		fs->fwd_dropped += (nb_rx - nb_tx);
1159 		do {
1160 			rte_pktmbuf_free(tx_pkts_burst[nb_tx]);
1161 		} while (++nb_tx < nb_rx);
1162 	}
1163 
1164 	get_end_cycles(fs, start_tsc);
1165 }
1166 
1167 struct fwd_engine csum_fwd_engine = {
1168 	.fwd_mode_name  = "csum",
1169 	.port_fwd_begin = NULL,
1170 	.port_fwd_end   = NULL,
1171 	.packet_fwd     = pkt_burst_checksum_forward,
1172 };
1173