xref: /dpdk/lib/gro/gro_udp4.c (revision 03ab51eafda992874a48c392ca66ffb577fe2b71)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2020 Inspur Corporation
3  */
4 
5 #include <rte_malloc.h>
6 #include <rte_mbuf.h>
7 #include <rte_cycles.h>
8 #include <rte_ethdev.h>
9 
10 #include "gro_udp4.h"
11 
12 void *
13 gro_udp4_tbl_create(uint16_t socket_id,
14 		uint16_t max_flow_num,
15 		uint16_t max_item_per_flow)
16 {
17 	struct gro_udp4_tbl *tbl;
18 	size_t size;
19 	uint32_t entries_num, i;
20 
21 	entries_num = max_flow_num * max_item_per_flow;
22 	entries_num = RTE_MIN(entries_num, GRO_UDP4_TBL_MAX_ITEM_NUM);
23 
24 	if (entries_num == 0)
25 		return NULL;
26 
27 	tbl = rte_zmalloc_socket(__func__,
28 			sizeof(struct gro_udp4_tbl),
29 			RTE_CACHE_LINE_SIZE,
30 			socket_id);
31 	if (tbl == NULL)
32 		return NULL;
33 
34 	size = sizeof(struct gro_udp4_item) * entries_num;
35 	tbl->items = rte_zmalloc_socket(__func__,
36 			size,
37 			RTE_CACHE_LINE_SIZE,
38 			socket_id);
39 	if (tbl->items == NULL) {
40 		rte_free(tbl);
41 		return NULL;
42 	}
43 	tbl->max_item_num = entries_num;
44 
45 	size = sizeof(struct gro_udp4_flow) * entries_num;
46 	tbl->flows = rte_zmalloc_socket(__func__,
47 			size,
48 			RTE_CACHE_LINE_SIZE,
49 			socket_id);
50 	if (tbl->flows == NULL) {
51 		rte_free(tbl->items);
52 		rte_free(tbl);
53 		return NULL;
54 	}
55 	/* INVALID_ARRAY_INDEX indicates an empty flow */
56 	for (i = 0; i < entries_num; i++)
57 		tbl->flows[i].start_index = INVALID_ARRAY_INDEX;
58 	tbl->max_flow_num = entries_num;
59 
60 	return tbl;
61 }
62 
63 void
64 gro_udp4_tbl_destroy(void *tbl)
65 {
66 	struct gro_udp4_tbl *udp_tbl = tbl;
67 
68 	if (udp_tbl) {
69 		rte_free(udp_tbl->items);
70 		rte_free(udp_tbl->flows);
71 	}
72 	rte_free(udp_tbl);
73 }
74 
75 static inline uint32_t
76 find_an_empty_item(struct gro_udp4_tbl *tbl)
77 {
78 	uint32_t i;
79 	uint32_t max_item_num = tbl->max_item_num;
80 
81 	for (i = 0; i < max_item_num; i++)
82 		if (tbl->items[i].firstseg == NULL)
83 			return i;
84 	return INVALID_ARRAY_INDEX;
85 }
86 
87 static inline uint32_t
88 find_an_empty_flow(struct gro_udp4_tbl *tbl)
89 {
90 	uint32_t i;
91 	uint32_t max_flow_num = tbl->max_flow_num;
92 
93 	for (i = 0; i < max_flow_num; i++)
94 		if (tbl->flows[i].start_index == INVALID_ARRAY_INDEX)
95 			return i;
96 	return INVALID_ARRAY_INDEX;
97 }
98 
99 static inline uint32_t
100 insert_new_item(struct gro_udp4_tbl *tbl,
101 		struct rte_mbuf *pkt,
102 		uint64_t start_time,
103 		uint32_t prev_idx,
104 		uint16_t frag_offset,
105 		uint8_t is_last_frag)
106 {
107 	uint32_t item_idx;
108 
109 	item_idx = find_an_empty_item(tbl);
110 	if (unlikely(item_idx == INVALID_ARRAY_INDEX))
111 		return INVALID_ARRAY_INDEX;
112 
113 	tbl->items[item_idx].firstseg = pkt;
114 	tbl->items[item_idx].lastseg = rte_pktmbuf_lastseg(pkt);
115 	tbl->items[item_idx].start_time = start_time;
116 	tbl->items[item_idx].next_pkt_idx = INVALID_ARRAY_INDEX;
117 	tbl->items[item_idx].frag_offset = frag_offset;
118 	tbl->items[item_idx].is_last_frag = is_last_frag;
119 	tbl->items[item_idx].nb_merged = 1;
120 	tbl->item_num++;
121 
122 	/* if the previous packet exists, chain them together. */
123 	if (prev_idx != INVALID_ARRAY_INDEX) {
124 		tbl->items[item_idx].next_pkt_idx =
125 			tbl->items[prev_idx].next_pkt_idx;
126 		tbl->items[prev_idx].next_pkt_idx = item_idx;
127 	}
128 
129 	return item_idx;
130 }
131 
132 static inline uint32_t
133 delete_item(struct gro_udp4_tbl *tbl, uint32_t item_idx,
134 		uint32_t prev_item_idx)
135 {
136 	uint32_t next_idx = tbl->items[item_idx].next_pkt_idx;
137 
138 	/* NULL indicates an empty item */
139 	tbl->items[item_idx].firstseg = NULL;
140 	tbl->item_num--;
141 	if (prev_item_idx != INVALID_ARRAY_INDEX)
142 		tbl->items[prev_item_idx].next_pkt_idx = next_idx;
143 
144 	return next_idx;
145 }
146 
147 static inline uint32_t
148 insert_new_flow(struct gro_udp4_tbl *tbl,
149 		struct udp4_flow_key *src,
150 		uint32_t item_idx)
151 {
152 	struct udp4_flow_key *dst;
153 	uint32_t flow_idx;
154 
155 	flow_idx = find_an_empty_flow(tbl);
156 	if (unlikely(flow_idx == INVALID_ARRAY_INDEX))
157 		return INVALID_ARRAY_INDEX;
158 
159 	dst = &(tbl->flows[flow_idx].key);
160 
161 	rte_ether_addr_copy(&(src->eth_saddr), &(dst->eth_saddr));
162 	rte_ether_addr_copy(&(src->eth_daddr), &(dst->eth_daddr));
163 	dst->ip_src_addr = src->ip_src_addr;
164 	dst->ip_dst_addr = src->ip_dst_addr;
165 	dst->ip_id = src->ip_id;
166 
167 	tbl->flows[flow_idx].start_index = item_idx;
168 	tbl->flow_num++;
169 
170 	return flow_idx;
171 }
172 
173 /*
174  * update the packet length for the flushed packet.
175  */
176 static inline void
177 update_header(struct gro_udp4_item *item)
178 {
179 	struct rte_ipv4_hdr *ipv4_hdr;
180 	struct rte_mbuf *pkt = item->firstseg;
181 	uint16_t frag_offset;
182 
183 	ipv4_hdr = (struct rte_ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
184 			pkt->l2_len);
185 	ipv4_hdr->total_length = rte_cpu_to_be_16(pkt->pkt_len -
186 			pkt->l2_len);
187 
188 	/* Clear MF bit if it is last fragment */
189 	if (item->is_last_frag) {
190 		frag_offset = rte_be_to_cpu_16(ipv4_hdr->fragment_offset);
191 		ipv4_hdr->fragment_offset =
192 			rte_cpu_to_be_16(frag_offset & ~RTE_IPV4_HDR_MF_FLAG);
193 	}
194 }
195 
196 int32_t
197 gro_udp4_reassemble(struct rte_mbuf *pkt,
198 		struct gro_udp4_tbl *tbl,
199 		uint64_t start_time)
200 {
201 	struct rte_ether_hdr *eth_hdr;
202 	struct rte_ipv4_hdr *ipv4_hdr;
203 	uint16_t ip_dl;
204 	uint16_t ip_id, hdr_len;
205 	uint16_t frag_offset = 0;
206 	uint8_t is_last_frag;
207 
208 	struct udp4_flow_key key;
209 	uint32_t cur_idx, prev_idx, item_idx;
210 	uint32_t i, max_flow_num, remaining_flow_num;
211 	int cmp;
212 	uint8_t find;
213 
214 	eth_hdr = rte_pktmbuf_mtod(pkt, struct rte_ether_hdr *);
215 	ipv4_hdr = (struct rte_ipv4_hdr *)((char *)eth_hdr + pkt->l2_len);
216 	hdr_len = pkt->l2_len + pkt->l3_len;
217 
218 	/*
219 	 * Don't process non-fragment packet.
220 	 */
221 	if (!is_ipv4_fragment(ipv4_hdr))
222 		return -1;
223 
224 	/*
225 	 * Don't process the packet whose payload length is less than or
226 	 * equal to 0.
227 	 */
228 	if (pkt->pkt_len <= hdr_len)
229 		return -1;
230 
231 	ip_dl = rte_be_to_cpu_16(ipv4_hdr->total_length);
232 	if (ip_dl <= pkt->l3_len)
233 		return -1;
234 
235 	ip_dl -= pkt->l3_len;
236 	ip_id = rte_be_to_cpu_16(ipv4_hdr->packet_id);
237 	frag_offset = rte_be_to_cpu_16(ipv4_hdr->fragment_offset);
238 	is_last_frag = ((frag_offset & RTE_IPV4_HDR_MF_FLAG) == 0) ? 1 : 0;
239 	frag_offset = (uint16_t)(frag_offset & RTE_IPV4_HDR_OFFSET_MASK) << 3;
240 
241 	rte_ether_addr_copy(&(eth_hdr->src_addr), &(key.eth_saddr));
242 	rte_ether_addr_copy(&(eth_hdr->dst_addr), &(key.eth_daddr));
243 	key.ip_src_addr = ipv4_hdr->src_addr;
244 	key.ip_dst_addr = ipv4_hdr->dst_addr;
245 	key.ip_id = ip_id;
246 
247 	/* Search for a matched flow. */
248 	max_flow_num = tbl->max_flow_num;
249 	remaining_flow_num = tbl->flow_num;
250 	find = 0;
251 	for (i = 0; i < max_flow_num && remaining_flow_num; i++) {
252 		if (tbl->flows[i].start_index != INVALID_ARRAY_INDEX) {
253 			if (is_same_udp4_flow(tbl->flows[i].key, key)) {
254 				find = 1;
255 				break;
256 			}
257 			remaining_flow_num--;
258 		}
259 	}
260 
261 	/*
262 	 * Fail to find a matched flow. Insert a new flow and store the
263 	 * packet into the flow.
264 	 */
265 	if (find == 0) {
266 		item_idx = insert_new_item(tbl, pkt, start_time,
267 				INVALID_ARRAY_INDEX, frag_offset,
268 				is_last_frag);
269 		if (unlikely(item_idx == INVALID_ARRAY_INDEX))
270 			return -1;
271 		if (insert_new_flow(tbl, &key, item_idx) ==
272 				INVALID_ARRAY_INDEX) {
273 			/*
274 			 * Fail to insert a new flow, so delete the
275 			 * stored packet.
276 			 */
277 			delete_item(tbl, item_idx, INVALID_ARRAY_INDEX);
278 			return -1;
279 		}
280 		return 0;
281 	}
282 
283 	/*
284 	 * Check all packets in the flow and try to find a neighbor for
285 	 * the input packet.
286 	 */
287 	cur_idx = tbl->flows[i].start_index;
288 	prev_idx = cur_idx;
289 	do {
290 		cmp = udp4_check_neighbor(&(tbl->items[cur_idx]),
291 				frag_offset, ip_dl, 0);
292 		if (cmp) {
293 			if (merge_two_udp4_packets(&(tbl->items[cur_idx]),
294 						pkt, cmp, frag_offset,
295 						is_last_frag, 0))
296 				return 1;
297 			/*
298 			 * Fail to merge the two packets, as the packet
299 			 * length is greater than the max value. Store
300 			 * the packet into the flow.
301 			 */
302 			if (insert_new_item(tbl, pkt, start_time, prev_idx,
303 						frag_offset, is_last_frag) ==
304 					INVALID_ARRAY_INDEX)
305 				return -1;
306 			return 0;
307 		}
308 
309 		/* Ensure inserted items are ordered by frag_offset */
310 		if (frag_offset
311 			< tbl->items[cur_idx].frag_offset) {
312 			break;
313 		}
314 
315 		prev_idx = cur_idx;
316 		cur_idx = tbl->items[cur_idx].next_pkt_idx;
317 	} while (cur_idx != INVALID_ARRAY_INDEX);
318 
319 	/* Fail to find a neighbor, so store the packet into the flow. */
320 	if (cur_idx == tbl->flows[i].start_index) {
321 		/* Insert it before the first packet of the flow */
322 		item_idx = insert_new_item(tbl, pkt, start_time,
323 				INVALID_ARRAY_INDEX, frag_offset,
324 				is_last_frag);
325 		if (unlikely(item_idx == INVALID_ARRAY_INDEX))
326 			return -1;
327 		tbl->items[item_idx].next_pkt_idx = cur_idx;
328 		tbl->flows[i].start_index = item_idx;
329 	} else {
330 		if (insert_new_item(tbl, pkt, start_time, prev_idx,
331 				frag_offset, is_last_frag)
332 			== INVALID_ARRAY_INDEX)
333 			return -1;
334 	}
335 
336 	return 0;
337 }
338 
339 static int
340 gro_udp4_merge_items(struct gro_udp4_tbl *tbl,
341 			   uint32_t start_idx)
342 {
343 	uint16_t frag_offset;
344 	uint8_t is_last_frag;
345 	int16_t ip_dl;
346 	struct rte_mbuf *pkt;
347 	int cmp;
348 	uint32_t item_idx;
349 	uint16_t hdr_len;
350 
351 	item_idx = tbl->items[start_idx].next_pkt_idx;
352 	while (item_idx != INVALID_ARRAY_INDEX) {
353 		pkt = tbl->items[item_idx].firstseg;
354 		hdr_len = pkt->l2_len + pkt->l3_len;
355 		ip_dl = pkt->pkt_len - hdr_len;
356 		frag_offset = tbl->items[item_idx].frag_offset;
357 		is_last_frag = tbl->items[item_idx].is_last_frag;
358 		cmp = udp4_check_neighbor(&(tbl->items[start_idx]),
359 					frag_offset, ip_dl, 0);
360 		if (cmp) {
361 			if (merge_two_udp4_packets(
362 					&(tbl->items[start_idx]),
363 					pkt, cmp, frag_offset,
364 					is_last_frag, 0)) {
365 				item_idx = delete_item(tbl, item_idx,
366 							INVALID_ARRAY_INDEX);
367 				tbl->items[start_idx].next_pkt_idx
368 					= item_idx;
369 			} else
370 				return 0;
371 		} else
372 			return 0;
373 	}
374 
375 	return 0;
376 }
377 
378 uint16_t
379 gro_udp4_tbl_timeout_flush(struct gro_udp4_tbl *tbl,
380 		uint64_t flush_timestamp,
381 		struct rte_mbuf **out,
382 		uint16_t nb_out)
383 {
384 	uint16_t k = 0;
385 	uint32_t i, j;
386 	uint32_t max_flow_num = tbl->max_flow_num;
387 
388 	for (i = 0; i < max_flow_num; i++) {
389 		if (unlikely(tbl->flow_num == 0))
390 			return k;
391 
392 		j = tbl->flows[i].start_index;
393 		while (j != INVALID_ARRAY_INDEX) {
394 			if (tbl->items[j].start_time <= flush_timestamp) {
395 				gro_udp4_merge_items(tbl, j);
396 				out[k++] = tbl->items[j].firstseg;
397 				if (tbl->items[j].nb_merged > 1)
398 					update_header(&(tbl->items[j]));
399 				/*
400 				 * Delete the packet and get the next
401 				 * packet in the flow.
402 				 */
403 				j = delete_item(tbl, j, INVALID_ARRAY_INDEX);
404 				tbl->flows[i].start_index = j;
405 				if (j == INVALID_ARRAY_INDEX)
406 					tbl->flow_num--;
407 
408 				if (unlikely(k == nb_out))
409 					return k;
410 			} else
411 				/*
412 				 * Flushing packets does not strictly follow
413 				 * timestamp. It does not flush left packets of
414 				 * the flow this time once it finds one item
415 				 * whose start_time is greater than
416 				 * flush_timestamp. So go to check other flows.
417 				 */
418 				break;
419 		}
420 	}
421 	return k;
422 }
423 
424 uint32_t
425 gro_udp4_tbl_pkt_count(void *tbl)
426 {
427 	struct gro_udp4_tbl *gro_tbl = tbl;
428 
429 	if (gro_tbl)
430 		return gro_tbl->item_num;
431 
432 	return 0;
433 }
434