1 | // SPDX-License-Identifier: GPL-2.0 |
2 | #include <linux/types.h> |
3 | #include <linux/atmmpc.h> |
4 | #include <linux/slab.h> |
5 | #include <linux/time.h> |
6 | |
7 | #include "mpoa_caches.h" |
8 | #include "mpc.h" |
9 | |
10 | /* |
11 | * mpoa_caches.c: Implementation of ingress and egress cache |
12 | * handling functions |
13 | */ |
14 | |
15 | #if 0 |
16 | #define dprintk(format, args...) \ |
17 | printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */ |
18 | #else |
19 | #define dprintk(format, args...) \ |
20 | do { if (0) \ |
21 | printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\ |
22 | } while (0) |
23 | #endif |
24 | |
25 | #if 0 |
26 | #define ddprintk(format, args...) \ |
27 | printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */ |
28 | #else |
29 | #define ddprintk(format, args...) \ |
30 | do { if (0) \ |
31 | printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\ |
32 | } while (0) |
33 | #endif |
34 | |
35 | static in_cache_entry *in_cache_get(__be32 dst_ip, |
36 | struct mpoa_client *client) |
37 | { |
38 | in_cache_entry *entry; |
39 | |
40 | read_lock_bh(&client->ingress_lock); |
41 | entry = client->in_cache; |
42 | while (entry != NULL) { |
43 | if (entry->ctrl_info.in_dst_ip == dst_ip) { |
44 | refcount_inc(r: &entry->use); |
45 | read_unlock_bh(&client->ingress_lock); |
46 | return entry; |
47 | } |
48 | entry = entry->next; |
49 | } |
50 | read_unlock_bh(&client->ingress_lock); |
51 | |
52 | return NULL; |
53 | } |
54 | |
55 | static in_cache_entry *in_cache_get_with_mask(__be32 dst_ip, |
56 | struct mpoa_client *client, |
57 | __be32 mask) |
58 | { |
59 | in_cache_entry *entry; |
60 | |
61 | read_lock_bh(&client->ingress_lock); |
62 | entry = client->in_cache; |
63 | while (entry != NULL) { |
64 | if ((entry->ctrl_info.in_dst_ip & mask) == (dst_ip & mask)) { |
65 | refcount_inc(r: &entry->use); |
66 | read_unlock_bh(&client->ingress_lock); |
67 | return entry; |
68 | } |
69 | entry = entry->next; |
70 | } |
71 | read_unlock_bh(&client->ingress_lock); |
72 | |
73 | return NULL; |
74 | |
75 | } |
76 | |
77 | static in_cache_entry *in_cache_get_by_vcc(struct atm_vcc *vcc, |
78 | struct mpoa_client *client) |
79 | { |
80 | in_cache_entry *entry; |
81 | |
82 | read_lock_bh(&client->ingress_lock); |
83 | entry = client->in_cache; |
84 | while (entry != NULL) { |
85 | if (entry->shortcut == vcc) { |
86 | refcount_inc(r: &entry->use); |
87 | read_unlock_bh(&client->ingress_lock); |
88 | return entry; |
89 | } |
90 | entry = entry->next; |
91 | } |
92 | read_unlock_bh(&client->ingress_lock); |
93 | |
94 | return NULL; |
95 | } |
96 | |
97 | static in_cache_entry *in_cache_add_entry(__be32 dst_ip, |
98 | struct mpoa_client *client) |
99 | { |
100 | in_cache_entry *entry = kzalloc(size: sizeof(in_cache_entry), GFP_KERNEL); |
101 | |
102 | if (entry == NULL) { |
103 | pr_info("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n" ); |
104 | return NULL; |
105 | } |
106 | |
107 | dprintk("adding an ingress entry, ip = %pI4\n" , &dst_ip); |
108 | |
109 | refcount_set(r: &entry->use, n: 1); |
110 | dprintk("new_in_cache_entry: about to lock\n" ); |
111 | write_lock_bh(&client->ingress_lock); |
112 | entry->next = client->in_cache; |
113 | entry->prev = NULL; |
114 | if (client->in_cache != NULL) |
115 | client->in_cache->prev = entry; |
116 | client->in_cache = entry; |
117 | |
118 | memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN); |
119 | entry->ctrl_info.in_dst_ip = dst_ip; |
120 | entry->time = ktime_get_seconds(); |
121 | entry->retry_time = client->parameters.mpc_p4; |
122 | entry->count = 1; |
123 | entry->entry_state = INGRESS_INVALID; |
124 | entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT; |
125 | refcount_inc(r: &entry->use); |
126 | |
127 | write_unlock_bh(&client->ingress_lock); |
128 | dprintk("new_in_cache_entry: unlocked\n" ); |
129 | |
130 | return entry; |
131 | } |
132 | |
133 | static int cache_hit(in_cache_entry *entry, struct mpoa_client *mpc) |
134 | { |
135 | struct atm_mpoa_qos *qos; |
136 | struct k_message msg; |
137 | |
138 | entry->count++; |
139 | if (entry->entry_state == INGRESS_RESOLVED && entry->shortcut != NULL) |
140 | return OPEN; |
141 | |
142 | if (entry->entry_state == INGRESS_REFRESHING) { |
143 | if (entry->count > mpc->parameters.mpc_p1) { |
144 | msg.type = SND_MPOA_RES_RQST; |
145 | msg.content.in_info = entry->ctrl_info; |
146 | memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN); |
147 | qos = atm_mpoa_search_qos(dst_ip: entry->ctrl_info.in_dst_ip); |
148 | if (qos != NULL) |
149 | msg.qos = qos->qos; |
150 | msg_to_mpoad(msg: &msg, mpc); |
151 | entry->reply_wait = ktime_get_seconds(); |
152 | entry->entry_state = INGRESS_RESOLVING; |
153 | } |
154 | if (entry->shortcut != NULL) |
155 | return OPEN; |
156 | return CLOSED; |
157 | } |
158 | |
159 | if (entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL) |
160 | return OPEN; |
161 | |
162 | if (entry->count > mpc->parameters.mpc_p1 && |
163 | entry->entry_state == INGRESS_INVALID) { |
164 | dprintk("(%s) threshold exceeded for ip %pI4, sending MPOA res req\n" , |
165 | mpc->dev->name, &entry->ctrl_info.in_dst_ip); |
166 | entry->entry_state = INGRESS_RESOLVING; |
167 | msg.type = SND_MPOA_RES_RQST; |
168 | memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN); |
169 | msg.content.in_info = entry->ctrl_info; |
170 | qos = atm_mpoa_search_qos(dst_ip: entry->ctrl_info.in_dst_ip); |
171 | if (qos != NULL) |
172 | msg.qos = qos->qos; |
173 | msg_to_mpoad(msg: &msg, mpc); |
174 | entry->reply_wait = ktime_get_seconds(); |
175 | } |
176 | |
177 | return CLOSED; |
178 | } |
179 | |
180 | static void in_cache_put(in_cache_entry *entry) |
181 | { |
182 | if (refcount_dec_and_test(r: &entry->use)) { |
183 | kfree_sensitive(objp: entry); |
184 | } |
185 | } |
186 | |
187 | /* |
188 | * This should be called with write lock on |
189 | */ |
190 | static void in_cache_remove_entry(in_cache_entry *entry, |
191 | struct mpoa_client *client) |
192 | { |
193 | struct atm_vcc *vcc; |
194 | struct k_message msg; |
195 | |
196 | vcc = entry->shortcut; |
197 | dprintk("removing an ingress entry, ip = %pI4\n" , |
198 | &entry->ctrl_info.in_dst_ip); |
199 | |
200 | if (entry->prev != NULL) |
201 | entry->prev->next = entry->next; |
202 | else |
203 | client->in_cache = entry->next; |
204 | if (entry->next != NULL) |
205 | entry->next->prev = entry->prev; |
206 | client->in_ops->put(entry); |
207 | if (client->in_cache == NULL && client->eg_cache == NULL) { |
208 | msg.type = STOP_KEEP_ALIVE_SM; |
209 | msg_to_mpoad(msg: &msg, mpc: client); |
210 | } |
211 | |
212 | /* Check if the egress side still uses this VCC */ |
213 | if (vcc != NULL) { |
214 | eg_cache_entry *eg_entry = client->eg_ops->get_by_vcc(vcc, |
215 | client); |
216 | if (eg_entry != NULL) { |
217 | client->eg_ops->put(eg_entry); |
218 | return; |
219 | } |
220 | vcc_release_async(vcc, reply: -EPIPE); |
221 | } |
222 | } |
223 | |
224 | /* Call this every MPC-p2 seconds... Not exactly correct solution, |
225 | but an easy one... */ |
226 | static void clear_count_and_expired(struct mpoa_client *client) |
227 | { |
228 | in_cache_entry *entry, *next_entry; |
229 | time64_t now; |
230 | |
231 | now = ktime_get_seconds(); |
232 | |
233 | write_lock_bh(&client->ingress_lock); |
234 | entry = client->in_cache; |
235 | while (entry != NULL) { |
236 | entry->count = 0; |
237 | next_entry = entry->next; |
238 | if ((now - entry->time) > entry->ctrl_info.holding_time) { |
239 | dprintk("holding time expired, ip = %pI4\n" , |
240 | &entry->ctrl_info.in_dst_ip); |
241 | client->in_ops->remove_entry(entry, client); |
242 | } |
243 | entry = next_entry; |
244 | } |
245 | write_unlock_bh(&client->ingress_lock); |
246 | } |
247 | |
248 | /* Call this every MPC-p4 seconds. */ |
249 | static void check_resolving_entries(struct mpoa_client *client) |
250 | { |
251 | |
252 | struct atm_mpoa_qos *qos; |
253 | in_cache_entry *entry; |
254 | time64_t now; |
255 | struct k_message msg; |
256 | |
257 | now = ktime_get_seconds(); |
258 | |
259 | read_lock_bh(&client->ingress_lock); |
260 | entry = client->in_cache; |
261 | while (entry != NULL) { |
262 | if (entry->entry_state == INGRESS_RESOLVING) { |
263 | |
264 | if ((now - entry->hold_down) |
265 | < client->parameters.mpc_p6) { |
266 | entry = entry->next; /* Entry in hold down */ |
267 | continue; |
268 | } |
269 | if ((now - entry->reply_wait) > entry->retry_time) { |
270 | entry->retry_time = MPC_C1 * (entry->retry_time); |
271 | /* |
272 | * Retry time maximum exceeded, |
273 | * put entry in hold down. |
274 | */ |
275 | if (entry->retry_time > client->parameters.mpc_p5) { |
276 | entry->hold_down = ktime_get_seconds(); |
277 | entry->retry_time = client->parameters.mpc_p4; |
278 | entry = entry->next; |
279 | continue; |
280 | } |
281 | /* Ask daemon to send a resolution request. */ |
282 | memset(&entry->hold_down, 0, sizeof(time64_t)); |
283 | msg.type = SND_MPOA_RES_RTRY; |
284 | memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN); |
285 | msg.content.in_info = entry->ctrl_info; |
286 | qos = atm_mpoa_search_qos(dst_ip: entry->ctrl_info.in_dst_ip); |
287 | if (qos != NULL) |
288 | msg.qos = qos->qos; |
289 | msg_to_mpoad(msg: &msg, mpc: client); |
290 | entry->reply_wait = ktime_get_seconds(); |
291 | } |
292 | } |
293 | entry = entry->next; |
294 | } |
295 | read_unlock_bh(&client->ingress_lock); |
296 | } |
297 | |
298 | /* Call this every MPC-p5 seconds. */ |
299 | static void refresh_entries(struct mpoa_client *client) |
300 | { |
301 | time64_t now; |
302 | struct in_cache_entry *entry = client->in_cache; |
303 | |
304 | ddprintk("refresh_entries\n" ); |
305 | now = ktime_get_seconds(); |
306 | |
307 | read_lock_bh(&client->ingress_lock); |
308 | while (entry != NULL) { |
309 | if (entry->entry_state == INGRESS_RESOLVED) { |
310 | if (!(entry->refresh_time)) |
311 | entry->refresh_time = (2 * (entry->ctrl_info.holding_time))/3; |
312 | if ((now - entry->reply_wait) > |
313 | entry->refresh_time) { |
314 | dprintk("refreshing an entry.\n" ); |
315 | entry->entry_state = INGRESS_REFRESHING; |
316 | |
317 | } |
318 | } |
319 | entry = entry->next; |
320 | } |
321 | read_unlock_bh(&client->ingress_lock); |
322 | } |
323 | |
324 | static void in_destroy_cache(struct mpoa_client *mpc) |
325 | { |
326 | write_lock_irq(&mpc->ingress_lock); |
327 | while (mpc->in_cache != NULL) |
328 | mpc->in_ops->remove_entry(mpc->in_cache, mpc); |
329 | write_unlock_irq(&mpc->ingress_lock); |
330 | } |
331 | |
332 | static eg_cache_entry *eg_cache_get_by_cache_id(__be32 cache_id, |
333 | struct mpoa_client *mpc) |
334 | { |
335 | eg_cache_entry *entry; |
336 | |
337 | read_lock_irq(&mpc->egress_lock); |
338 | entry = mpc->eg_cache; |
339 | while (entry != NULL) { |
340 | if (entry->ctrl_info.cache_id == cache_id) { |
341 | refcount_inc(r: &entry->use); |
342 | read_unlock_irq(&mpc->egress_lock); |
343 | return entry; |
344 | } |
345 | entry = entry->next; |
346 | } |
347 | read_unlock_irq(&mpc->egress_lock); |
348 | |
349 | return NULL; |
350 | } |
351 | |
352 | /* This can be called from any context since it saves CPU flags */ |
353 | static eg_cache_entry *eg_cache_get_by_tag(__be32 tag, struct mpoa_client *mpc) |
354 | { |
355 | unsigned long flags; |
356 | eg_cache_entry *entry; |
357 | |
358 | read_lock_irqsave(&mpc->egress_lock, flags); |
359 | entry = mpc->eg_cache; |
360 | while (entry != NULL) { |
361 | if (entry->ctrl_info.tag == tag) { |
362 | refcount_inc(r: &entry->use); |
363 | read_unlock_irqrestore(&mpc->egress_lock, flags); |
364 | return entry; |
365 | } |
366 | entry = entry->next; |
367 | } |
368 | read_unlock_irqrestore(&mpc->egress_lock, flags); |
369 | |
370 | return NULL; |
371 | } |
372 | |
373 | /* This can be called from any context since it saves CPU flags */ |
374 | static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc, |
375 | struct mpoa_client *mpc) |
376 | { |
377 | unsigned long flags; |
378 | eg_cache_entry *entry; |
379 | |
380 | read_lock_irqsave(&mpc->egress_lock, flags); |
381 | entry = mpc->eg_cache; |
382 | while (entry != NULL) { |
383 | if (entry->shortcut == vcc) { |
384 | refcount_inc(r: &entry->use); |
385 | read_unlock_irqrestore(&mpc->egress_lock, flags); |
386 | return entry; |
387 | } |
388 | entry = entry->next; |
389 | } |
390 | read_unlock_irqrestore(&mpc->egress_lock, flags); |
391 | |
392 | return NULL; |
393 | } |
394 | |
395 | static eg_cache_entry *eg_cache_get_by_src_ip(__be32 ipaddr, |
396 | struct mpoa_client *mpc) |
397 | { |
398 | eg_cache_entry *entry; |
399 | |
400 | read_lock_irq(&mpc->egress_lock); |
401 | entry = mpc->eg_cache; |
402 | while (entry != NULL) { |
403 | if (entry->latest_ip_addr == ipaddr) { |
404 | refcount_inc(r: &entry->use); |
405 | read_unlock_irq(&mpc->egress_lock); |
406 | return entry; |
407 | } |
408 | entry = entry->next; |
409 | } |
410 | read_unlock_irq(&mpc->egress_lock); |
411 | |
412 | return NULL; |
413 | } |
414 | |
415 | static void eg_cache_put(eg_cache_entry *entry) |
416 | { |
417 | if (refcount_dec_and_test(r: &entry->use)) { |
418 | kfree_sensitive(objp: entry); |
419 | } |
420 | } |
421 | |
422 | /* |
423 | * This should be called with write lock on |
424 | */ |
425 | static void eg_cache_remove_entry(eg_cache_entry *entry, |
426 | struct mpoa_client *client) |
427 | { |
428 | struct atm_vcc *vcc; |
429 | struct k_message msg; |
430 | |
431 | vcc = entry->shortcut; |
432 | dprintk("removing an egress entry.\n" ); |
433 | if (entry->prev != NULL) |
434 | entry->prev->next = entry->next; |
435 | else |
436 | client->eg_cache = entry->next; |
437 | if (entry->next != NULL) |
438 | entry->next->prev = entry->prev; |
439 | client->eg_ops->put(entry); |
440 | if (client->in_cache == NULL && client->eg_cache == NULL) { |
441 | msg.type = STOP_KEEP_ALIVE_SM; |
442 | msg_to_mpoad(msg: &msg, mpc: client); |
443 | } |
444 | |
445 | /* Check if the ingress side still uses this VCC */ |
446 | if (vcc != NULL) { |
447 | in_cache_entry *in_entry = client->in_ops->get_by_vcc(vcc, client); |
448 | if (in_entry != NULL) { |
449 | client->in_ops->put(in_entry); |
450 | return; |
451 | } |
452 | vcc_release_async(vcc, reply: -EPIPE); |
453 | } |
454 | } |
455 | |
456 | static eg_cache_entry *eg_cache_add_entry(struct k_message *msg, |
457 | struct mpoa_client *client) |
458 | { |
459 | eg_cache_entry *entry = kzalloc(size: sizeof(eg_cache_entry), GFP_KERNEL); |
460 | |
461 | if (entry == NULL) { |
462 | pr_info("out of memory\n" ); |
463 | return NULL; |
464 | } |
465 | |
466 | dprintk("adding an egress entry, ip = %pI4, this should be our IP\n" , |
467 | &msg->content.eg_info.eg_dst_ip); |
468 | |
469 | refcount_set(r: &entry->use, n: 1); |
470 | dprintk("new_eg_cache_entry: about to lock\n" ); |
471 | write_lock_irq(&client->egress_lock); |
472 | entry->next = client->eg_cache; |
473 | entry->prev = NULL; |
474 | if (client->eg_cache != NULL) |
475 | client->eg_cache->prev = entry; |
476 | client->eg_cache = entry; |
477 | |
478 | memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN); |
479 | entry->ctrl_info = msg->content.eg_info; |
480 | entry->time = ktime_get_seconds(); |
481 | entry->entry_state = EGRESS_RESOLVED; |
482 | dprintk("new_eg_cache_entry cache_id %u\n" , |
483 | ntohl(entry->ctrl_info.cache_id)); |
484 | dprintk("mps_ip = %pI4\n" , &entry->ctrl_info.mps_ip); |
485 | refcount_inc(r: &entry->use); |
486 | |
487 | write_unlock_irq(&client->egress_lock); |
488 | dprintk("new_eg_cache_entry: unlocked\n" ); |
489 | |
490 | return entry; |
491 | } |
492 | |
493 | static void update_eg_cache_entry(eg_cache_entry *entry, uint16_t holding_time) |
494 | { |
495 | entry->time = ktime_get_seconds(); |
496 | entry->entry_state = EGRESS_RESOLVED; |
497 | entry->ctrl_info.holding_time = holding_time; |
498 | } |
499 | |
500 | static void clear_expired(struct mpoa_client *client) |
501 | { |
502 | eg_cache_entry *entry, *next_entry; |
503 | time64_t now; |
504 | struct k_message msg; |
505 | |
506 | now = ktime_get_seconds(); |
507 | |
508 | write_lock_irq(&client->egress_lock); |
509 | entry = client->eg_cache; |
510 | while (entry != NULL) { |
511 | next_entry = entry->next; |
512 | if ((now - entry->time) > entry->ctrl_info.holding_time) { |
513 | msg.type = SND_EGRESS_PURGE; |
514 | msg.content.eg_info = entry->ctrl_info; |
515 | dprintk("egress_cache: holding time expired, cache_id = %u.\n" , |
516 | ntohl(entry->ctrl_info.cache_id)); |
517 | msg_to_mpoad(msg: &msg, mpc: client); |
518 | client->eg_ops->remove_entry(entry, client); |
519 | } |
520 | entry = next_entry; |
521 | } |
522 | write_unlock_irq(&client->egress_lock); |
523 | } |
524 | |
525 | static void eg_destroy_cache(struct mpoa_client *mpc) |
526 | { |
527 | write_lock_irq(&mpc->egress_lock); |
528 | while (mpc->eg_cache != NULL) |
529 | mpc->eg_ops->remove_entry(mpc->eg_cache, mpc); |
530 | write_unlock_irq(&mpc->egress_lock); |
531 | } |
532 | |
533 | |
534 | static const struct in_cache_ops ingress_ops = { |
535 | .add_entry = in_cache_add_entry, |
536 | .get = in_cache_get, |
537 | .get_with_mask = in_cache_get_with_mask, |
538 | .get_by_vcc = in_cache_get_by_vcc, |
539 | .put = in_cache_put, |
540 | .remove_entry = in_cache_remove_entry, |
541 | .cache_hit = cache_hit, |
542 | .clear_count = clear_count_and_expired, |
543 | .check_resolving = check_resolving_entries, |
544 | .refresh = refresh_entries, |
545 | .destroy_cache = in_destroy_cache |
546 | }; |
547 | |
548 | static const struct eg_cache_ops egress_ops = { |
549 | .add_entry = eg_cache_add_entry, |
550 | .get_by_cache_id = eg_cache_get_by_cache_id, |
551 | .get_by_tag = eg_cache_get_by_tag, |
552 | .get_by_vcc = eg_cache_get_by_vcc, |
553 | .get_by_src_ip = eg_cache_get_by_src_ip, |
554 | .put = eg_cache_put, |
555 | .remove_entry = eg_cache_remove_entry, |
556 | .update = update_eg_cache_entry, |
557 | .clear_expired = clear_expired, |
558 | .destroy_cache = eg_destroy_cache |
559 | }; |
560 | |
561 | void atm_mpoa_init_cache(struct mpoa_client *mpc) |
562 | { |
563 | mpc->in_ops = &ingress_ops; |
564 | mpc->eg_ops = &egress_ops; |
565 | } |
566 | |