1 /*
2  * Copyright (C) 2017 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 #include <linux/hash.h>
35 #include <linux/hashtable.h>
36 #include <linux/jhash.h>
37 #include <linux/vmalloc.h>
38 #include <net/pkt_cls.h>
39 
40 #include "cmsg.h"
41 #include "main.h"
42 #include "../nfp_app.h"
43 
44 struct nfp_mask_id_table {
45 	struct hlist_node link;
46 	u32 hash_key;
47 	u32 ref_cnt;
48 	u8 mask_id;
49 };
50 
51 static int nfp_release_stats_entry(struct nfp_app *app, u32 stats_context_id)
52 {
53 	struct nfp_flower_priv *priv = app->priv;
54 	struct circ_buf *ring;
55 
56 	ring = &priv->stats_ids.free_list;
57 	/* Check if buffer is full. */
58 	if (!CIRC_SPACE(ring->head, ring->tail, NFP_FL_STATS_ENTRY_RS *
59 			NFP_FL_STATS_ELEM_RS -
60 			NFP_FL_STATS_ELEM_RS + 1))
61 		return -ENOBUFS;
62 
63 	memcpy(&ring->buf[ring->head], &stats_context_id, NFP_FL_STATS_ELEM_RS);
64 	ring->head = (ring->head + NFP_FL_STATS_ELEM_RS) %
65 		     (NFP_FL_STATS_ENTRY_RS * NFP_FL_STATS_ELEM_RS);
66 
67 	return 0;
68 }
69 
70 static int nfp_get_stats_entry(struct nfp_app *app, u32 *stats_context_id)
71 {
72 	struct nfp_flower_priv *priv = app->priv;
73 	u32 freed_stats_id, temp_stats_id;
74 	struct circ_buf *ring;
75 
76 	ring = &priv->stats_ids.free_list;
77 	freed_stats_id = NFP_FL_STATS_ENTRY_RS;
78 	/* Check for unallocated entries first. */
79 	if (priv->stats_ids.init_unalloc > 0) {
80 		*stats_context_id = priv->stats_ids.init_unalloc - 1;
81 		priv->stats_ids.init_unalloc--;
82 		return 0;
83 	}
84 
85 	/* Check if buffer is empty. */
86 	if (ring->head == ring->tail) {
87 		*stats_context_id = freed_stats_id;
88 		return -ENOENT;
89 	}
90 
91 	memcpy(&temp_stats_id, &ring->buf[ring->tail], NFP_FL_STATS_ELEM_RS);
92 	*stats_context_id = temp_stats_id;
93 	memcpy(&ring->buf[ring->tail], &freed_stats_id, NFP_FL_STATS_ELEM_RS);
94 	ring->tail = (ring->tail + NFP_FL_STATS_ELEM_RS) %
95 		     (NFP_FL_STATS_ENTRY_RS * NFP_FL_STATS_ELEM_RS);
96 
97 	return 0;
98 }
99 
100 /* Must be called with either RTNL or rcu_read_lock */
101 struct nfp_fl_payload *
102 nfp_flower_search_fl_table(struct nfp_app *app, unsigned long tc_flower_cookie,
103 			   struct net_device *netdev, __be32 host_ctx)
104 {
105 	struct nfp_flower_priv *priv = app->priv;
106 	struct nfp_fl_payload *flower_entry;
107 
108 	hash_for_each_possible_rcu(priv->flow_table, flower_entry, link,
109 				   tc_flower_cookie)
110 		if (flower_entry->tc_flower_cookie == tc_flower_cookie &&
111 		    (!netdev || flower_entry->ingress_dev == netdev) &&
112 		    (host_ctx == NFP_FL_STATS_CTX_DONT_CARE ||
113 		     flower_entry->meta.host_ctx_id == host_ctx))
114 			return flower_entry;
115 
116 	return NULL;
117 }
118 
119 static void
120 nfp_flower_update_stats(struct nfp_app *app, struct nfp_fl_stats_frame *stats)
121 {
122 	struct nfp_fl_payload *nfp_flow;
123 	unsigned long flower_cookie;
124 
125 	flower_cookie = be64_to_cpu(stats->stats_cookie);
126 
127 	rcu_read_lock();
128 	nfp_flow = nfp_flower_search_fl_table(app, flower_cookie, NULL,
129 					      stats->stats_con_id);
130 	if (!nfp_flow)
131 		goto exit_rcu_unlock;
132 
133 	spin_lock(&nfp_flow->lock);
134 	nfp_flow->stats.pkts += be32_to_cpu(stats->pkt_count);
135 	nfp_flow->stats.bytes += be64_to_cpu(stats->byte_count);
136 	nfp_flow->stats.used = jiffies;
137 	spin_unlock(&nfp_flow->lock);
138 
139 exit_rcu_unlock:
140 	rcu_read_unlock();
141 }
142 
143 void nfp_flower_rx_flow_stats(struct nfp_app *app, struct sk_buff *skb)
144 {
145 	unsigned int msg_len = nfp_flower_cmsg_get_data_len(skb);
146 	struct nfp_fl_stats_frame *stats_frame;
147 	unsigned char *msg;
148 	int i;
149 
150 	msg = nfp_flower_cmsg_get_data(skb);
151 
152 	stats_frame = (struct nfp_fl_stats_frame *)msg;
153 	for (i = 0; i < msg_len / sizeof(*stats_frame); i++)
154 		nfp_flower_update_stats(app, stats_frame + i);
155 }
156 
157 static int nfp_release_mask_id(struct nfp_app *app, u8 mask_id)
158 {
159 	struct nfp_flower_priv *priv = app->priv;
160 	struct circ_buf *ring;
161 	struct timespec64 now;
162 
163 	ring = &priv->mask_ids.mask_id_free_list;
164 	/* Checking if buffer is full. */
165 	if (CIRC_SPACE(ring->head, ring->tail, NFP_FLOWER_MASK_ENTRY_RS) == 0)
166 		return -ENOBUFS;
167 
168 	memcpy(&ring->buf[ring->head], &mask_id, NFP_FLOWER_MASK_ELEMENT_RS);
169 	ring->head = (ring->head + NFP_FLOWER_MASK_ELEMENT_RS) %
170 		     (NFP_FLOWER_MASK_ENTRY_RS * NFP_FLOWER_MASK_ELEMENT_RS);
171 
172 	getnstimeofday64(&now);
173 	priv->mask_ids.last_used[mask_id] = now;
174 
175 	return 0;
176 }
177 
178 static int nfp_mask_alloc(struct nfp_app *app, u8 *mask_id)
179 {
180 	struct nfp_flower_priv *priv = app->priv;
181 	struct timespec64 delta, now;
182 	struct circ_buf *ring;
183 	u8 temp_id, freed_id;
184 
185 	ring = &priv->mask_ids.mask_id_free_list;
186 	freed_id = NFP_FLOWER_MASK_ENTRY_RS - 1;
187 	/* Checking for unallocated entries first. */
188 	if (priv->mask_ids.init_unallocated > 0) {
189 		*mask_id = priv->mask_ids.init_unallocated;
190 		priv->mask_ids.init_unallocated--;
191 		return 0;
192 	}
193 
194 	/* Checking if buffer is empty. */
195 	if (ring->head == ring->tail)
196 		goto err_not_found;
197 
198 	memcpy(&temp_id, &ring->buf[ring->tail], NFP_FLOWER_MASK_ELEMENT_RS);
199 	*mask_id = temp_id;
200 
201 	getnstimeofday64(&now);
202 	delta = timespec64_sub(now, priv->mask_ids.last_used[*mask_id]);
203 
204 	if (timespec64_to_ns(&delta) < NFP_FL_MASK_REUSE_TIME_NS)
205 		goto err_not_found;
206 
207 	memcpy(&ring->buf[ring->tail], &freed_id, NFP_FLOWER_MASK_ELEMENT_RS);
208 	ring->tail = (ring->tail + NFP_FLOWER_MASK_ELEMENT_RS) %
209 		     (NFP_FLOWER_MASK_ENTRY_RS * NFP_FLOWER_MASK_ELEMENT_RS);
210 
211 	return 0;
212 
213 err_not_found:
214 	*mask_id = freed_id;
215 	return -ENOENT;
216 }
217 
218 static int
219 nfp_add_mask_table(struct nfp_app *app, char *mask_data, u32 mask_len)
220 {
221 	struct nfp_flower_priv *priv = app->priv;
222 	struct nfp_mask_id_table *mask_entry;
223 	unsigned long hash_key;
224 	u8 mask_id;
225 
226 	if (nfp_mask_alloc(app, &mask_id))
227 		return -ENOENT;
228 
229 	mask_entry = kmalloc(sizeof(*mask_entry), GFP_KERNEL);
230 	if (!mask_entry) {
231 		nfp_release_mask_id(app, mask_id);
232 		return -ENOMEM;
233 	}
234 
235 	INIT_HLIST_NODE(&mask_entry->link);
236 	mask_entry->mask_id = mask_id;
237 	hash_key = jhash(mask_data, mask_len, priv->mask_id_seed);
238 	mask_entry->hash_key = hash_key;
239 	mask_entry->ref_cnt = 1;
240 	hash_add(priv->mask_table, &mask_entry->link, hash_key);
241 
242 	return mask_id;
243 }
244 
245 static struct nfp_mask_id_table *
246 nfp_search_mask_table(struct nfp_app *app, char *mask_data, u32 mask_len)
247 {
248 	struct nfp_flower_priv *priv = app->priv;
249 	struct nfp_mask_id_table *mask_entry;
250 	unsigned long hash_key;
251 
252 	hash_key = jhash(mask_data, mask_len, priv->mask_id_seed);
253 
254 	hash_for_each_possible(priv->mask_table, mask_entry, link, hash_key)
255 		if (mask_entry->hash_key == hash_key)
256 			return mask_entry;
257 
258 	return NULL;
259 }
260 
261 static int
262 nfp_find_in_mask_table(struct nfp_app *app, char *mask_data, u32 mask_len)
263 {
264 	struct nfp_mask_id_table *mask_entry;
265 
266 	mask_entry = nfp_search_mask_table(app, mask_data, mask_len);
267 	if (!mask_entry)
268 		return -ENOENT;
269 
270 	mask_entry->ref_cnt++;
271 
272 	/* Casting u8 to int for later use. */
273 	return mask_entry->mask_id;
274 }
275 
276 static bool
277 nfp_check_mask_add(struct nfp_app *app, char *mask_data, u32 mask_len,
278 		   u8 *meta_flags, u8 *mask_id)
279 {
280 	int id;
281 
282 	id = nfp_find_in_mask_table(app, mask_data, mask_len);
283 	if (id < 0) {
284 		id = nfp_add_mask_table(app, mask_data, mask_len);
285 		if (id < 0)
286 			return false;
287 		*meta_flags |= NFP_FL_META_FLAG_MANAGE_MASK;
288 	}
289 	*mask_id = id;
290 
291 	return true;
292 }
293 
294 static bool
295 nfp_check_mask_remove(struct nfp_app *app, char *mask_data, u32 mask_len,
296 		      u8 *meta_flags, u8 *mask_id)
297 {
298 	struct nfp_mask_id_table *mask_entry;
299 
300 	mask_entry = nfp_search_mask_table(app, mask_data, mask_len);
301 	if (!mask_entry)
302 		return false;
303 
304 	if (meta_flags)
305 		*meta_flags &= ~NFP_FL_META_FLAG_MANAGE_MASK;
306 
307 	*mask_id = mask_entry->mask_id;
308 	mask_entry->ref_cnt--;
309 	if (!mask_entry->ref_cnt) {
310 		hash_del(&mask_entry->link);
311 		nfp_release_mask_id(app, *mask_id);
312 		kfree(mask_entry);
313 		if (meta_flags)
314 			*meta_flags |= NFP_FL_META_FLAG_MANAGE_MASK;
315 	}
316 
317 	return true;
318 }
319 
320 int nfp_compile_flow_metadata(struct nfp_app *app,
321 			      struct tc_cls_flower_offload *flow,
322 			      struct nfp_fl_payload *nfp_flow,
323 			      struct net_device *netdev)
324 {
325 	struct nfp_flower_priv *priv = app->priv;
326 	struct nfp_fl_payload *check_entry;
327 	u8 new_mask_id;
328 	u32 stats_cxt;
329 
330 	if (nfp_get_stats_entry(app, &stats_cxt))
331 		return -ENOENT;
332 
333 	nfp_flow->meta.host_ctx_id = cpu_to_be32(stats_cxt);
334 	nfp_flow->meta.host_cookie = cpu_to_be64(flow->cookie);
335 
336 	new_mask_id = 0;
337 	if (!nfp_check_mask_add(app, nfp_flow->mask_data,
338 				nfp_flow->meta.mask_len,
339 				&nfp_flow->meta.flags, &new_mask_id)) {
340 		if (nfp_release_stats_entry(app, stats_cxt))
341 			return -EINVAL;
342 		return -ENOENT;
343 	}
344 
345 	nfp_flow->meta.flow_version = cpu_to_be64(priv->flower_version);
346 	priv->flower_version++;
347 
348 	/* Update flow payload with mask ids. */
349 	nfp_flow->unmasked_data[NFP_FL_MASK_ID_LOCATION] = new_mask_id;
350 	nfp_flow->stats.pkts = 0;
351 	nfp_flow->stats.bytes = 0;
352 	nfp_flow->stats.used = jiffies;
353 
354 	check_entry = nfp_flower_search_fl_table(app, flow->cookie, netdev,
355 						 NFP_FL_STATS_CTX_DONT_CARE);
356 	if (check_entry) {
357 		if (nfp_release_stats_entry(app, stats_cxt))
358 			return -EINVAL;
359 
360 		if (!nfp_check_mask_remove(app, nfp_flow->mask_data,
361 					   nfp_flow->meta.mask_len,
362 					   NULL, &new_mask_id))
363 			return -EINVAL;
364 
365 		return -EEXIST;
366 	}
367 
368 	return 0;
369 }
370 
371 int nfp_modify_flow_metadata(struct nfp_app *app,
372 			     struct nfp_fl_payload *nfp_flow)
373 {
374 	struct nfp_flower_priv *priv = app->priv;
375 	u8 new_mask_id = 0;
376 	u32 temp_ctx_id;
377 
378 	nfp_check_mask_remove(app, nfp_flow->mask_data,
379 			      nfp_flow->meta.mask_len, &nfp_flow->meta.flags,
380 			      &new_mask_id);
381 
382 	nfp_flow->meta.flow_version = cpu_to_be64(priv->flower_version);
383 	priv->flower_version++;
384 
385 	/* Update flow payload with mask ids. */
386 	nfp_flow->unmasked_data[NFP_FL_MASK_ID_LOCATION] = new_mask_id;
387 
388 	/* Release the stats ctx id. */
389 	temp_ctx_id = be32_to_cpu(nfp_flow->meta.host_ctx_id);
390 
391 	return nfp_release_stats_entry(app, temp_ctx_id);
392 }
393 
394 int nfp_flower_metadata_init(struct nfp_app *app)
395 {
396 	struct nfp_flower_priv *priv = app->priv;
397 
398 	hash_init(priv->mask_table);
399 	hash_init(priv->flow_table);
400 	get_random_bytes(&priv->mask_id_seed, sizeof(priv->mask_id_seed));
401 
402 	/* Init ring buffer and unallocated mask_ids. */
403 	priv->mask_ids.mask_id_free_list.buf =
404 		kmalloc_array(NFP_FLOWER_MASK_ENTRY_RS,
405 			      NFP_FLOWER_MASK_ELEMENT_RS, GFP_KERNEL);
406 	if (!priv->mask_ids.mask_id_free_list.buf)
407 		return -ENOMEM;
408 
409 	priv->mask_ids.init_unallocated = NFP_FLOWER_MASK_ENTRY_RS - 1;
410 
411 	/* Init timestamps for mask id*/
412 	priv->mask_ids.last_used =
413 		kmalloc_array(NFP_FLOWER_MASK_ENTRY_RS,
414 			      sizeof(*priv->mask_ids.last_used), GFP_KERNEL);
415 	if (!priv->mask_ids.last_used)
416 		goto err_free_mask_id;
417 
418 	/* Init ring buffer and unallocated stats_ids. */
419 	priv->stats_ids.free_list.buf =
420 		vmalloc(array_size(NFP_FL_STATS_ELEM_RS,
421 				   NFP_FL_STATS_ENTRY_RS));
422 	if (!priv->stats_ids.free_list.buf)
423 		goto err_free_last_used;
424 
425 	priv->stats_ids.init_unalloc = NFP_FL_REPEATED_HASH_MAX;
426 
427 	return 0;
428 
429 err_free_last_used:
430 	kfree(priv->mask_ids.last_used);
431 err_free_mask_id:
432 	kfree(priv->mask_ids.mask_id_free_list.buf);
433 	return -ENOMEM;
434 }
435 
436 void nfp_flower_metadata_cleanup(struct nfp_app *app)
437 {
438 	struct nfp_flower_priv *priv = app->priv;
439 
440 	if (!priv)
441 		return;
442 
443 	kfree(priv->mask_ids.mask_id_free_list.buf);
444 	kfree(priv->mask_ids.last_used);
445 	vfree(priv->stats_ids.free_list.buf);
446 }
447