1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2017-2018 Netronome Systems, Inc. */
3 
4 #include <linux/hash.h>
5 #include <linux/hashtable.h>
6 #include <linux/jhash.h>
7 #include <linux/math64.h>
8 #include <linux/vmalloc.h>
9 #include <net/pkt_cls.h>
10 
11 #include "cmsg.h"
12 #include "main.h"
13 #include "../nfp_app.h"
14 
15 struct nfp_mask_id_table {
16 	struct hlist_node link;
17 	u32 hash_key;
18 	u32 ref_cnt;
19 	u8 mask_id;
20 };
21 
22 struct nfp_fl_flow_table_cmp_arg {
23 	struct net_device *netdev;
24 	unsigned long cookie;
25 };
26 
27 struct nfp_fl_stats_ctx_to_flow {
28 	struct rhash_head ht_node;
29 	u32 stats_cxt;
30 	struct nfp_fl_payload *flow;
31 };
32 
33 static const struct rhashtable_params stats_ctx_table_params = {
34 	.key_offset	= offsetof(struct nfp_fl_stats_ctx_to_flow, stats_cxt),
35 	.head_offset	= offsetof(struct nfp_fl_stats_ctx_to_flow, ht_node),
36 	.key_len	= sizeof(u32),
37 };
38 
39 static int nfp_release_stats_entry(struct nfp_app *app, u32 stats_context_id)
40 {
41 	struct nfp_flower_priv *priv = app->priv;
42 	struct circ_buf *ring;
43 
44 	ring = &priv->stats_ids.free_list;
45 	/* Check if buffer is full. */
46 	if (!CIRC_SPACE(ring->head, ring->tail,
47 			priv->stats_ring_size * NFP_FL_STATS_ELEM_RS -
48 			NFP_FL_STATS_ELEM_RS + 1))
49 		return -ENOBUFS;
50 
51 	memcpy(&ring->buf[ring->head], &stats_context_id, NFP_FL_STATS_ELEM_RS);
52 	ring->head = (ring->head + NFP_FL_STATS_ELEM_RS) %
53 		     (priv->stats_ring_size * NFP_FL_STATS_ELEM_RS);
54 
55 	return 0;
56 }
57 
58 static int nfp_get_stats_entry(struct nfp_app *app, u32 *stats_context_id)
59 {
60 	struct nfp_flower_priv *priv = app->priv;
61 	u32 freed_stats_id, temp_stats_id;
62 	struct circ_buf *ring;
63 
64 	ring = &priv->stats_ids.free_list;
65 	freed_stats_id = priv->stats_ring_size;
66 	/* Check for unallocated entries first. */
67 	if (priv->stats_ids.init_unalloc > 0) {
68 		*stats_context_id =
69 			FIELD_PREP(NFP_FL_STAT_ID_STAT,
70 				   priv->stats_ids.init_unalloc - 1) |
71 			FIELD_PREP(NFP_FL_STAT_ID_MU_NUM,
72 				   priv->active_mem_unit);
73 
74 		if (++priv->active_mem_unit == priv->total_mem_units) {
75 			priv->stats_ids.init_unalloc--;
76 			priv->active_mem_unit = 0;
77 		}
78 
79 		return 0;
80 	}
81 
82 	/* Check if buffer is empty. */
83 	if (ring->head == ring->tail) {
84 		*stats_context_id = freed_stats_id;
85 		return -ENOENT;
86 	}
87 
88 	memcpy(&temp_stats_id, &ring->buf[ring->tail], NFP_FL_STATS_ELEM_RS);
89 	*stats_context_id = temp_stats_id;
90 	memcpy(&ring->buf[ring->tail], &freed_stats_id, NFP_FL_STATS_ELEM_RS);
91 	ring->tail = (ring->tail + NFP_FL_STATS_ELEM_RS) %
92 		     (priv->stats_ring_size * NFP_FL_STATS_ELEM_RS);
93 
94 	return 0;
95 }
96 
97 /* Must be called with either RTNL or rcu_read_lock */
98 struct nfp_fl_payload *
99 nfp_flower_search_fl_table(struct nfp_app *app, unsigned long tc_flower_cookie,
100 			   struct net_device *netdev)
101 {
102 	struct nfp_fl_flow_table_cmp_arg flower_cmp_arg;
103 	struct nfp_flower_priv *priv = app->priv;
104 
105 	flower_cmp_arg.netdev = netdev;
106 	flower_cmp_arg.cookie = tc_flower_cookie;
107 
108 	return rhashtable_lookup_fast(&priv->flow_table, &flower_cmp_arg,
109 				      nfp_flower_table_params);
110 }
111 
112 void nfp_flower_rx_flow_stats(struct nfp_app *app, struct sk_buff *skb)
113 {
114 	unsigned int msg_len = nfp_flower_cmsg_get_data_len(skb);
115 	struct nfp_flower_priv *priv = app->priv;
116 	struct nfp_fl_stats_frame *stats;
117 	unsigned char *msg;
118 	u32 ctx_id;
119 	int i;
120 
121 	msg = nfp_flower_cmsg_get_data(skb);
122 
123 	spin_lock(&priv->stats_lock);
124 	for (i = 0; i < msg_len / sizeof(*stats); i++) {
125 		stats = (struct nfp_fl_stats_frame *)msg + i;
126 		ctx_id = be32_to_cpu(stats->stats_con_id);
127 		priv->stats[ctx_id].pkts += be32_to_cpu(stats->pkt_count);
128 		priv->stats[ctx_id].bytes += be64_to_cpu(stats->byte_count);
129 		priv->stats[ctx_id].used = jiffies;
130 	}
131 	spin_unlock(&priv->stats_lock);
132 }
133 
134 static int nfp_release_mask_id(struct nfp_app *app, u8 mask_id)
135 {
136 	struct nfp_flower_priv *priv = app->priv;
137 	struct circ_buf *ring;
138 
139 	ring = &priv->mask_ids.mask_id_free_list;
140 	/* Checking if buffer is full. */
141 	if (CIRC_SPACE(ring->head, ring->tail, NFP_FLOWER_MASK_ENTRY_RS) == 0)
142 		return -ENOBUFS;
143 
144 	memcpy(&ring->buf[ring->head], &mask_id, NFP_FLOWER_MASK_ELEMENT_RS);
145 	ring->head = (ring->head + NFP_FLOWER_MASK_ELEMENT_RS) %
146 		     (NFP_FLOWER_MASK_ENTRY_RS * NFP_FLOWER_MASK_ELEMENT_RS);
147 
148 	priv->mask_ids.last_used[mask_id] = ktime_get();
149 
150 	return 0;
151 }
152 
153 static int nfp_mask_alloc(struct nfp_app *app, u8 *mask_id)
154 {
155 	struct nfp_flower_priv *priv = app->priv;
156 	ktime_t reuse_timeout;
157 	struct circ_buf *ring;
158 	u8 temp_id, freed_id;
159 
160 	ring = &priv->mask_ids.mask_id_free_list;
161 	freed_id = NFP_FLOWER_MASK_ENTRY_RS - 1;
162 	/* Checking for unallocated entries first. */
163 	if (priv->mask_ids.init_unallocated > 0) {
164 		*mask_id = priv->mask_ids.init_unallocated;
165 		priv->mask_ids.init_unallocated--;
166 		return 0;
167 	}
168 
169 	/* Checking if buffer is empty. */
170 	if (ring->head == ring->tail)
171 		goto err_not_found;
172 
173 	memcpy(&temp_id, &ring->buf[ring->tail], NFP_FLOWER_MASK_ELEMENT_RS);
174 	*mask_id = temp_id;
175 
176 	reuse_timeout = ktime_add_ns(priv->mask_ids.last_used[*mask_id],
177 				     NFP_FL_MASK_REUSE_TIME_NS);
178 
179 	if (ktime_before(ktime_get(), reuse_timeout))
180 		goto err_not_found;
181 
182 	memcpy(&ring->buf[ring->tail], &freed_id, NFP_FLOWER_MASK_ELEMENT_RS);
183 	ring->tail = (ring->tail + NFP_FLOWER_MASK_ELEMENT_RS) %
184 		     (NFP_FLOWER_MASK_ENTRY_RS * NFP_FLOWER_MASK_ELEMENT_RS);
185 
186 	return 0;
187 
188 err_not_found:
189 	*mask_id = freed_id;
190 	return -ENOENT;
191 }
192 
193 static int
194 nfp_add_mask_table(struct nfp_app *app, char *mask_data, u32 mask_len)
195 {
196 	struct nfp_flower_priv *priv = app->priv;
197 	struct nfp_mask_id_table *mask_entry;
198 	unsigned long hash_key;
199 	u8 mask_id;
200 
201 	if (nfp_mask_alloc(app, &mask_id))
202 		return -ENOENT;
203 
204 	mask_entry = kmalloc(sizeof(*mask_entry), GFP_KERNEL);
205 	if (!mask_entry) {
206 		nfp_release_mask_id(app, mask_id);
207 		return -ENOMEM;
208 	}
209 
210 	INIT_HLIST_NODE(&mask_entry->link);
211 	mask_entry->mask_id = mask_id;
212 	hash_key = jhash(mask_data, mask_len, priv->mask_id_seed);
213 	mask_entry->hash_key = hash_key;
214 	mask_entry->ref_cnt = 1;
215 	hash_add(priv->mask_table, &mask_entry->link, hash_key);
216 
217 	return mask_id;
218 }
219 
220 static struct nfp_mask_id_table *
221 nfp_search_mask_table(struct nfp_app *app, char *mask_data, u32 mask_len)
222 {
223 	struct nfp_flower_priv *priv = app->priv;
224 	struct nfp_mask_id_table *mask_entry;
225 	unsigned long hash_key;
226 
227 	hash_key = jhash(mask_data, mask_len, priv->mask_id_seed);
228 
229 	hash_for_each_possible(priv->mask_table, mask_entry, link, hash_key)
230 		if (mask_entry->hash_key == hash_key)
231 			return mask_entry;
232 
233 	return NULL;
234 }
235 
236 static int
237 nfp_find_in_mask_table(struct nfp_app *app, char *mask_data, u32 mask_len)
238 {
239 	struct nfp_mask_id_table *mask_entry;
240 
241 	mask_entry = nfp_search_mask_table(app, mask_data, mask_len);
242 	if (!mask_entry)
243 		return -ENOENT;
244 
245 	mask_entry->ref_cnt++;
246 
247 	/* Casting u8 to int for later use. */
248 	return mask_entry->mask_id;
249 }
250 
251 static bool
252 nfp_check_mask_add(struct nfp_app *app, char *mask_data, u32 mask_len,
253 		   u8 *meta_flags, u8 *mask_id)
254 {
255 	int id;
256 
257 	id = nfp_find_in_mask_table(app, mask_data, mask_len);
258 	if (id < 0) {
259 		id = nfp_add_mask_table(app, mask_data, mask_len);
260 		if (id < 0)
261 			return false;
262 		*meta_flags |= NFP_FL_META_FLAG_MANAGE_MASK;
263 	}
264 	*mask_id = id;
265 
266 	return true;
267 }
268 
269 static bool
270 nfp_check_mask_remove(struct nfp_app *app, char *mask_data, u32 mask_len,
271 		      u8 *meta_flags, u8 *mask_id)
272 {
273 	struct nfp_mask_id_table *mask_entry;
274 
275 	mask_entry = nfp_search_mask_table(app, mask_data, mask_len);
276 	if (!mask_entry)
277 		return false;
278 
279 	*mask_id = mask_entry->mask_id;
280 	mask_entry->ref_cnt--;
281 	if (!mask_entry->ref_cnt) {
282 		hash_del(&mask_entry->link);
283 		nfp_release_mask_id(app, *mask_id);
284 		kfree(mask_entry);
285 		if (meta_flags)
286 			*meta_flags |= NFP_FL_META_FLAG_MANAGE_MASK;
287 	}
288 
289 	return true;
290 }
291 
292 int nfp_compile_flow_metadata(struct nfp_app *app,
293 			      struct flow_cls_offload *flow,
294 			      struct nfp_fl_payload *nfp_flow,
295 			      struct net_device *netdev,
296 			      struct netlink_ext_ack *extack)
297 {
298 	struct nfp_fl_stats_ctx_to_flow *ctx_entry;
299 	struct nfp_flower_priv *priv = app->priv;
300 	struct nfp_fl_payload *check_entry;
301 	u8 new_mask_id;
302 	u32 stats_cxt;
303 	int err;
304 
305 	err = nfp_get_stats_entry(app, &stats_cxt);
306 	if (err) {
307 		NL_SET_ERR_MSG_MOD(extack, "invalid entry: cannot allocate new stats context");
308 		return err;
309 	}
310 
311 	nfp_flow->meta.host_ctx_id = cpu_to_be32(stats_cxt);
312 	nfp_flow->meta.host_cookie = cpu_to_be64(flow->cookie);
313 	nfp_flow->ingress_dev = netdev;
314 
315 	ctx_entry = kzalloc(sizeof(*ctx_entry), GFP_KERNEL);
316 	if (!ctx_entry) {
317 		err = -ENOMEM;
318 		goto err_release_stats;
319 	}
320 
321 	ctx_entry->stats_cxt = stats_cxt;
322 	ctx_entry->flow = nfp_flow;
323 
324 	if (rhashtable_insert_fast(&priv->stats_ctx_table, &ctx_entry->ht_node,
325 				   stats_ctx_table_params)) {
326 		err = -ENOMEM;
327 		goto err_free_ctx_entry;
328 	}
329 
330 	new_mask_id = 0;
331 	if (!nfp_check_mask_add(app, nfp_flow->mask_data,
332 				nfp_flow->meta.mask_len,
333 				&nfp_flow->meta.flags, &new_mask_id)) {
334 		NL_SET_ERR_MSG_MOD(extack, "invalid entry: cannot allocate a new mask id");
335 		if (nfp_release_stats_entry(app, stats_cxt)) {
336 			NL_SET_ERR_MSG_MOD(extack, "invalid entry: cannot release stats context");
337 			err = -EINVAL;
338 			goto err_remove_rhash;
339 		}
340 		err = -ENOENT;
341 		goto err_remove_rhash;
342 	}
343 
344 	nfp_flow->meta.flow_version = cpu_to_be64(priv->flower_version);
345 	priv->flower_version++;
346 
347 	/* Update flow payload with mask ids. */
348 	nfp_flow->unmasked_data[NFP_FL_MASK_ID_LOCATION] = new_mask_id;
349 	priv->stats[stats_cxt].pkts = 0;
350 	priv->stats[stats_cxt].bytes = 0;
351 	priv->stats[stats_cxt].used = jiffies;
352 
353 	check_entry = nfp_flower_search_fl_table(app, flow->cookie, netdev);
354 	if (check_entry) {
355 		NL_SET_ERR_MSG_MOD(extack, "invalid entry: cannot offload duplicate flow entry");
356 		if (nfp_release_stats_entry(app, stats_cxt)) {
357 			NL_SET_ERR_MSG_MOD(extack, "invalid entry: cannot release stats context");
358 			err = -EINVAL;
359 			goto err_remove_mask;
360 		}
361 
362 		if (!nfp_check_mask_remove(app, nfp_flow->mask_data,
363 					   nfp_flow->meta.mask_len,
364 					   NULL, &new_mask_id)) {
365 			NL_SET_ERR_MSG_MOD(extack, "invalid entry: cannot release mask id");
366 			err = -EINVAL;
367 			goto err_remove_mask;
368 		}
369 
370 		err = -EEXIST;
371 		goto err_remove_mask;
372 	}
373 
374 	return 0;
375 
376 err_remove_mask:
377 	nfp_check_mask_remove(app, nfp_flow->mask_data, nfp_flow->meta.mask_len,
378 			      NULL, &new_mask_id);
379 err_remove_rhash:
380 	WARN_ON_ONCE(rhashtable_remove_fast(&priv->stats_ctx_table,
381 					    &ctx_entry->ht_node,
382 					    stats_ctx_table_params));
383 err_free_ctx_entry:
384 	kfree(ctx_entry);
385 err_release_stats:
386 	nfp_release_stats_entry(app, stats_cxt);
387 
388 	return err;
389 }
390 
391 void __nfp_modify_flow_metadata(struct nfp_flower_priv *priv,
392 				struct nfp_fl_payload *nfp_flow)
393 {
394 	nfp_flow->meta.flags &= ~NFP_FL_META_FLAG_MANAGE_MASK;
395 	nfp_flow->meta.flow_version = cpu_to_be64(priv->flower_version);
396 	priv->flower_version++;
397 }
398 
399 int nfp_modify_flow_metadata(struct nfp_app *app,
400 			     struct nfp_fl_payload *nfp_flow)
401 {
402 	struct nfp_fl_stats_ctx_to_flow *ctx_entry;
403 	struct nfp_flower_priv *priv = app->priv;
404 	u8 new_mask_id = 0;
405 	u32 temp_ctx_id;
406 
407 	__nfp_modify_flow_metadata(priv, nfp_flow);
408 
409 	nfp_check_mask_remove(app, nfp_flow->mask_data,
410 			      nfp_flow->meta.mask_len, &nfp_flow->meta.flags,
411 			      &new_mask_id);
412 
413 	/* Update flow payload with mask ids. */
414 	nfp_flow->unmasked_data[NFP_FL_MASK_ID_LOCATION] = new_mask_id;
415 
416 	/* Release the stats ctx id and ctx to flow table entry. */
417 	temp_ctx_id = be32_to_cpu(nfp_flow->meta.host_ctx_id);
418 
419 	ctx_entry = rhashtable_lookup_fast(&priv->stats_ctx_table, &temp_ctx_id,
420 					   stats_ctx_table_params);
421 	if (!ctx_entry)
422 		return -ENOENT;
423 
424 	WARN_ON_ONCE(rhashtable_remove_fast(&priv->stats_ctx_table,
425 					    &ctx_entry->ht_node,
426 					    stats_ctx_table_params));
427 	kfree(ctx_entry);
428 
429 	return nfp_release_stats_entry(app, temp_ctx_id);
430 }
431 
432 struct nfp_fl_payload *
433 nfp_flower_get_fl_payload_from_ctx(struct nfp_app *app, u32 ctx_id)
434 {
435 	struct nfp_fl_stats_ctx_to_flow *ctx_entry;
436 	struct nfp_flower_priv *priv = app->priv;
437 
438 	ctx_entry = rhashtable_lookup_fast(&priv->stats_ctx_table, &ctx_id,
439 					   stats_ctx_table_params);
440 	if (!ctx_entry)
441 		return NULL;
442 
443 	return ctx_entry->flow;
444 }
445 
446 static int nfp_fl_obj_cmpfn(struct rhashtable_compare_arg *arg,
447 			    const void *obj)
448 {
449 	const struct nfp_fl_flow_table_cmp_arg *cmp_arg = arg->key;
450 	const struct nfp_fl_payload *flow_entry = obj;
451 
452 	if (flow_entry->ingress_dev == cmp_arg->netdev)
453 		return flow_entry->tc_flower_cookie != cmp_arg->cookie;
454 
455 	return 1;
456 }
457 
458 static u32 nfp_fl_obj_hashfn(const void *data, u32 len, u32 seed)
459 {
460 	const struct nfp_fl_payload *flower_entry = data;
461 
462 	return jhash2((u32 *)&flower_entry->tc_flower_cookie,
463 		      sizeof(flower_entry->tc_flower_cookie) / sizeof(u32),
464 		      seed);
465 }
466 
467 static u32 nfp_fl_key_hashfn(const void *data, u32 len, u32 seed)
468 {
469 	const struct nfp_fl_flow_table_cmp_arg *cmp_arg = data;
470 
471 	return jhash2((u32 *)&cmp_arg->cookie,
472 		      sizeof(cmp_arg->cookie) / sizeof(u32), seed);
473 }
474 
475 const struct rhashtable_params nfp_flower_table_params = {
476 	.head_offset		= offsetof(struct nfp_fl_payload, fl_node),
477 	.hashfn			= nfp_fl_key_hashfn,
478 	.obj_cmpfn		= nfp_fl_obj_cmpfn,
479 	.obj_hashfn		= nfp_fl_obj_hashfn,
480 	.automatic_shrinking	= true,
481 };
482 
483 int nfp_flower_metadata_init(struct nfp_app *app, u64 host_ctx_count,
484 			     unsigned int host_num_mems)
485 {
486 	struct nfp_flower_priv *priv = app->priv;
487 	int err, stats_size;
488 
489 	hash_init(priv->mask_table);
490 
491 	err = rhashtable_init(&priv->flow_table, &nfp_flower_table_params);
492 	if (err)
493 		return err;
494 
495 	err = rhashtable_init(&priv->stats_ctx_table, &stats_ctx_table_params);
496 	if (err)
497 		goto err_free_flow_table;
498 
499 	get_random_bytes(&priv->mask_id_seed, sizeof(priv->mask_id_seed));
500 
501 	/* Init ring buffer and unallocated mask_ids. */
502 	priv->mask_ids.mask_id_free_list.buf =
503 		kmalloc_array(NFP_FLOWER_MASK_ENTRY_RS,
504 			      NFP_FLOWER_MASK_ELEMENT_RS, GFP_KERNEL);
505 	if (!priv->mask_ids.mask_id_free_list.buf)
506 		goto err_free_stats_ctx_table;
507 
508 	priv->mask_ids.init_unallocated = NFP_FLOWER_MASK_ENTRY_RS - 1;
509 
510 	/* Init timestamps for mask id*/
511 	priv->mask_ids.last_used =
512 		kmalloc_array(NFP_FLOWER_MASK_ENTRY_RS,
513 			      sizeof(*priv->mask_ids.last_used), GFP_KERNEL);
514 	if (!priv->mask_ids.last_used)
515 		goto err_free_mask_id;
516 
517 	/* Init ring buffer and unallocated stats_ids. */
518 	priv->stats_ids.free_list.buf =
519 		vmalloc(array_size(NFP_FL_STATS_ELEM_RS,
520 				   priv->stats_ring_size));
521 	if (!priv->stats_ids.free_list.buf)
522 		goto err_free_last_used;
523 
524 	priv->stats_ids.init_unalloc = div_u64(host_ctx_count, host_num_mems);
525 
526 	stats_size = FIELD_PREP(NFP_FL_STAT_ID_STAT, host_ctx_count) |
527 		     FIELD_PREP(NFP_FL_STAT_ID_MU_NUM, host_num_mems - 1);
528 	priv->stats = kvmalloc_array(stats_size, sizeof(struct nfp_fl_stats),
529 				     GFP_KERNEL);
530 	if (!priv->stats)
531 		goto err_free_ring_buf;
532 
533 	spin_lock_init(&priv->stats_lock);
534 
535 	return 0;
536 
537 err_free_ring_buf:
538 	vfree(priv->stats_ids.free_list.buf);
539 err_free_last_used:
540 	kfree(priv->mask_ids.last_used);
541 err_free_mask_id:
542 	kfree(priv->mask_ids.mask_id_free_list.buf);
543 err_free_stats_ctx_table:
544 	rhashtable_destroy(&priv->stats_ctx_table);
545 err_free_flow_table:
546 	rhashtable_destroy(&priv->flow_table);
547 	return -ENOMEM;
548 }
549 
550 void nfp_flower_metadata_cleanup(struct nfp_app *app)
551 {
552 	struct nfp_flower_priv *priv = app->priv;
553 
554 	if (!priv)
555 		return;
556 
557 	rhashtable_free_and_destroy(&priv->flow_table,
558 				    nfp_check_rhashtable_empty, NULL);
559 	rhashtable_free_and_destroy(&priv->stats_ctx_table,
560 				    nfp_check_rhashtable_empty, NULL);
561 	kvfree(priv->stats);
562 	kfree(priv->mask_ids.mask_id_free_list.buf);
563 	kfree(priv->mask_ids.last_used);
564 	vfree(priv->stats_ids.free_list.buf);
565 }
566