xref: /dpdk/lib/node/ip6_rewrite.c (revision 7917b0d38e92e8b9ec5a870415b791420e10f11a)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(C) 2023 Marvell.
3  */
4 
5 #include <rte_ethdev.h>
6 #include <rte_ether.h>
7 #include <rte_graph.h>
8 #include <rte_graph_worker.h>
9 #include <rte_ip.h>
10 #include <rte_malloc.h>
11 #include <rte_vect.h>
12 
13 #include "rte_node_ip6_api.h"
14 
15 #include "ip6_rewrite_priv.h"
16 #include "node_private.h"
17 
18 struct ip6_rewrite_node_ctx {
19 	/* Dynamic offset to mbuf priv1 */
20 	int mbuf_priv1_off;
21 	/* Cached next index */
22 	uint16_t next_index;
23 };
24 
25 static struct ip6_rewrite_node_main *ip6_rewrite_nm;
26 
27 #define IP6_REWRITE_NODE_LAST_NEXT(ctx) \
28 	(((struct ip6_rewrite_node_ctx *)ctx)->next_index)
29 
30 #define IP6_REWRITE_NODE_PRIV1_OFF(ctx) \
31 	(((struct ip6_rewrite_node_ctx *)ctx)->mbuf_priv1_off)
32 
33 static uint16_t
34 ip6_rewrite_node_process(struct rte_graph *graph, struct rte_node *node,
35 			 void **objs, uint16_t nb_objs)
36 {
37 	struct rte_mbuf *mbuf0, *mbuf1, *mbuf2, *mbuf3, **pkts;
38 	struct ip6_rewrite_nh_header *nh = ip6_rewrite_nm->nh;
39 	const int dyn = IP6_REWRITE_NODE_PRIV1_OFF(node->ctx);
40 	uint16_t next0, next1, next2, next3, next_index;
41 	uint16_t n_left_from, held = 0, last_spec = 0;
42 	struct rte_ipv6_hdr *ip0, *ip1, *ip2, *ip3;
43 	void *d0, *d1, *d2, *d3;
44 	void **to_next, **from;
45 	rte_xmm_t priv01;
46 	rte_xmm_t priv23;
47 	int i;
48 
49 	/* Speculative next as last next */
50 	next_index = IP6_REWRITE_NODE_LAST_NEXT(node->ctx);
51 	rte_prefetch0(nh);
52 
53 	pkts = (struct rte_mbuf **)objs;
54 	from = objs;
55 	n_left_from = nb_objs;
56 
57 	for (i = 0; i < 4 && i < n_left_from; i++)
58 		rte_prefetch0(pkts[i]);
59 
60 	/* Get stream for the speculated next node */
61 	to_next = rte_node_next_stream_get(graph, node, next_index, nb_objs);
62 	/* Update Ethernet header of pkts */
63 	while (n_left_from >= 4) {
64 		if (likely(n_left_from > 7)) {
65 			/* Prefetch only next-mbuf struct and priv area.
66 			 * Data need not be prefetched as we only write.
67 			 */
68 			rte_prefetch0(pkts[4]);
69 			rte_prefetch0(pkts[5]);
70 			rte_prefetch0(pkts[6]);
71 			rte_prefetch0(pkts[7]);
72 		}
73 
74 		mbuf0 = pkts[0];
75 		mbuf1 = pkts[1];
76 		mbuf2 = pkts[2];
77 		mbuf3 = pkts[3];
78 
79 		pkts += 4;
80 		n_left_from -= 4;
81 		priv01.u64[0] = node_mbuf_priv1(mbuf0, dyn)->u;
82 		priv01.u64[1] = node_mbuf_priv1(mbuf1, dyn)->u;
83 		priv23.u64[0] = node_mbuf_priv1(mbuf2, dyn)->u;
84 		priv23.u64[1] = node_mbuf_priv1(mbuf3, dyn)->u;
85 
86 		/* Update next_hop rewrite ethernet hdr on mbuf0 */
87 		d0 = rte_pktmbuf_mtod(mbuf0, void *);
88 		rte_memcpy(d0, nh[priv01.u16[0]].rewrite_data,
89 			   nh[priv01.u16[0]].rewrite_len);
90 
91 		next0 = nh[priv01.u16[0]].tx_node;
92 		ip0 = (struct rte_ipv6_hdr *)((uint8_t *)d0 +
93 					      sizeof(struct rte_ether_hdr));
94 		ip0->hop_limits = priv01.u16[1] - 1;
95 
96 		/* Update next_hop rewrite ethernet hdr on mbuf1 */
97 		d1 = rte_pktmbuf_mtod(mbuf1, void *);
98 		rte_memcpy(d1, nh[priv01.u16[4]].rewrite_data,
99 			   nh[priv01.u16[4]].rewrite_len);
100 
101 		next1 = nh[priv01.u16[4]].tx_node;
102 		ip1 = (struct rte_ipv6_hdr *)((uint8_t *)d1 +
103 					      sizeof(struct rte_ether_hdr));
104 		ip1->hop_limits = priv01.u16[5] - 1;
105 
106 		/* Update next_hop rewrite ethernet hdr on mbuf2 */
107 		d2 = rte_pktmbuf_mtod(mbuf2, void *);
108 		rte_memcpy(d2, nh[priv23.u16[0]].rewrite_data,
109 			   nh[priv23.u16[0]].rewrite_len);
110 		next2 = nh[priv23.u16[0]].tx_node;
111 		ip2 = (struct rte_ipv6_hdr *)((uint8_t *)d2 +
112 					      sizeof(struct rte_ether_hdr));
113 		ip2->hop_limits = priv23.u16[1] - 1;
114 
115 		/* Update next_hop rewrite ethernet hdr on mbuf3 */
116 		d3 = rte_pktmbuf_mtod(mbuf3, void *);
117 		rte_memcpy(d3, nh[priv23.u16[4]].rewrite_data,
118 			   nh[priv23.u16[4]].rewrite_len);
119 
120 		next3 = nh[priv23.u16[4]].tx_node;
121 		ip3 = (struct rte_ipv6_hdr *)((uint8_t *)d3 +
122 					      sizeof(struct rte_ether_hdr));
123 		ip3->hop_limits = priv23.u16[5] - 1;
124 
125 		/* Enqueue four packets to next node */
126 		rte_edge_t fix_spec =
127 			((next_index == next0) && (next0 == next1) &&
128 			 (next1 == next2) && (next2 == next3));
129 
130 		if (unlikely(fix_spec == 0)) {
131 			/* Copy things successfully speculated till now */
132 			rte_memcpy(to_next, from, last_spec * sizeof(from[0]));
133 			from += last_spec;
134 			to_next += last_spec;
135 			held += last_spec;
136 			last_spec = 0;
137 
138 			/* next0 */
139 			if (next_index == next0) {
140 				to_next[0] = from[0];
141 				to_next++;
142 				held++;
143 			} else {
144 				rte_node_enqueue_x1(graph, node, next0,
145 						    from[0]);
146 			}
147 
148 			/* next1 */
149 			if (next_index == next1) {
150 				to_next[0] = from[1];
151 				to_next++;
152 				held++;
153 			} else {
154 				rte_node_enqueue_x1(graph, node, next1,
155 						    from[1]);
156 			}
157 
158 			/* next2 */
159 			if (next_index == next2) {
160 				to_next[0] = from[2];
161 				to_next++;
162 				held++;
163 			} else {
164 				rte_node_enqueue_x1(graph, node, next2,
165 						    from[2]);
166 			}
167 
168 			/* next3 */
169 			if (next_index == next3) {
170 				to_next[0] = from[3];
171 				to_next++;
172 				held++;
173 			} else {
174 				rte_node_enqueue_x1(graph, node, next3,
175 						    from[3]);
176 			}
177 
178 			from += 4;
179 
180 			/* Change speculation if last two are same */
181 			if ((next_index != next3) && (next2 == next3)) {
182 				/* Put the current speculated node */
183 				rte_node_next_stream_put(graph, node,
184 							 next_index, held);
185 				held = 0;
186 
187 				/* Get next speculated stream */
188 				next_index = next3;
189 				to_next = rte_node_next_stream_get(
190 					graph, node, next_index, nb_objs);
191 			}
192 		} else {
193 			last_spec += 4;
194 		}
195 	}
196 
197 	while (n_left_from > 0) {
198 		mbuf0 = pkts[0];
199 
200 		pkts += 1;
201 		n_left_from -= 1;
202 
203 		d0 = rte_pktmbuf_mtod(mbuf0, void *);
204 		rte_memcpy(d0, nh[node_mbuf_priv1(mbuf0, dyn)->nh].rewrite_data,
205 			   nh[node_mbuf_priv1(mbuf0, dyn)->nh].rewrite_len);
206 
207 		next0 = nh[node_mbuf_priv1(mbuf0, dyn)->nh].tx_node;
208 		ip0 = (struct rte_ipv6_hdr *)((uint8_t *)d0 +
209 					      sizeof(struct rte_ether_hdr));
210 		ip0->hop_limits = node_mbuf_priv1(mbuf0, dyn)->ttl - 1;
211 
212 		if (unlikely(next_index ^ next0)) {
213 			/* Copy things successfully speculated till now */
214 			rte_memcpy(to_next, from, last_spec * sizeof(from[0]));
215 			from += last_spec;
216 			to_next += last_spec;
217 			held += last_spec;
218 			last_spec = 0;
219 
220 			rte_node_enqueue_x1(graph, node, next0, from[0]);
221 			from += 1;
222 		} else {
223 			last_spec += 1;
224 		}
225 	}
226 
227 	/* !!! Home run !!! */
228 	if (likely(last_spec == nb_objs)) {
229 		rte_node_next_stream_move(graph, node, next_index);
230 		return nb_objs;
231 	}
232 
233 	held += last_spec;
234 	rte_memcpy(to_next, from, last_spec * sizeof(from[0]));
235 	rte_node_next_stream_put(graph, node, next_index, held);
236 	/* Save the last next used */
237 	IP6_REWRITE_NODE_LAST_NEXT(node->ctx) = next_index;
238 
239 	return nb_objs;
240 }
241 
242 static int
243 ip6_rewrite_node_init(const struct rte_graph *graph, struct rte_node *node)
244 {
245 	static bool init_once;
246 
247 	RTE_SET_USED(graph);
248 	RTE_BUILD_BUG_ON(sizeof(struct ip6_rewrite_node_ctx) > RTE_NODE_CTX_SZ);
249 
250 	if (!init_once) {
251 		node_mbuf_priv1_dynfield_offset = rte_mbuf_dynfield_register(
252 				&node_mbuf_priv1_dynfield_desc);
253 		if (node_mbuf_priv1_dynfield_offset < 0)
254 			return -rte_errno;
255 		init_once = true;
256 	}
257 	IP6_REWRITE_NODE_PRIV1_OFF(node->ctx) = node_mbuf_priv1_dynfield_offset;
258 
259 	node_dbg("ip6_rewrite", "Initialized ip6_rewrite node");
260 
261 	return 0;
262 }
263 
264 int
265 ip6_rewrite_set_next(uint16_t port_id, uint16_t next_index)
266 {
267 	if (ip6_rewrite_nm == NULL) {
268 		ip6_rewrite_nm = rte_zmalloc(
269 			"ip6_rewrite", sizeof(struct ip6_rewrite_node_main),
270 			RTE_CACHE_LINE_SIZE);
271 		if (ip6_rewrite_nm == NULL)
272 			return -ENOMEM;
273 	}
274 	ip6_rewrite_nm->next_index[port_id] = next_index;
275 
276 	return 0;
277 }
278 
279 int
280 rte_node_ip6_rewrite_add(uint16_t next_hop, uint8_t *rewrite_data,
281 			 uint8_t rewrite_len, uint16_t dst_port)
282 {
283 	struct ip6_rewrite_nh_header *nh;
284 
285 	if (next_hop >= RTE_GRAPH_IP6_REWRITE_MAX_NH)
286 		return -EINVAL;
287 
288 	if (rewrite_len > RTE_GRAPH_IP6_REWRITE_MAX_LEN)
289 		return -EINVAL;
290 
291 	if (ip6_rewrite_nm == NULL) {
292 		ip6_rewrite_nm = rte_zmalloc(
293 			"ip6_rewrite", sizeof(struct ip6_rewrite_node_main),
294 			RTE_CACHE_LINE_SIZE);
295 		if (ip6_rewrite_nm == NULL)
296 			return -ENOMEM;
297 	}
298 
299 	/* Check if dst port doesn't exist as edge */
300 	if (!ip6_rewrite_nm->next_index[dst_port])
301 		return -EINVAL;
302 
303 	/* Update next hop */
304 	nh = &ip6_rewrite_nm->nh[next_hop];
305 
306 	memcpy(nh->rewrite_data, rewrite_data, rewrite_len);
307 	nh->tx_node = ip6_rewrite_nm->next_index[dst_port];
308 	nh->rewrite_len = rewrite_len;
309 	nh->enabled = true;
310 
311 	return 0;
312 }
313 
314 static struct rte_node_register ip6_rewrite_node = {
315 	.process = ip6_rewrite_node_process,
316 	.name = "ip6_rewrite",
317 	/* Default edge i.e '0' is pkt drop */
318 	.nb_edges = 1,
319 	.next_nodes = {
320 		[0] = "pkt_drop",
321 	},
322 	.init = ip6_rewrite_node_init,
323 };
324 
325 struct rte_node_register *
326 ip6_rewrite_node_get(void)
327 {
328 	return &ip6_rewrite_node;
329 }
330 
331 RTE_NODE_REGISTER(ip6_rewrite_node);
332