1 #include <linux/types.h>
2 #include <linux/atmmpc.h>
3 #include <linux/slab.h>
4 #include <linux/time.h>
5
6 #include "mpoa_caches.h"
7 #include "mpc.h"
8
9 /*
10 * mpoa_caches.c: Implementation of ingress and egress cache
11 * handling functions
12 */
13
14 #if 0
15 #define dprintk(format, args...) \
16 printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */
17 #else
18 #define dprintk(format, args...) \
19 do { if (0) \
20 printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\
21 } while (0)
22 #endif
23
24 #if 0
25 #define ddprintk(format, args...) \
26 printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args) /* debug */
27 #else
28 #define ddprintk(format, args...) \
29 do { if (0) \
30 printk(KERN_DEBUG "mpoa:%s: " format, __FILE__, ##args);\
31 } while (0)
32 #endif
33
in_cache_get(__be32 dst_ip,struct mpoa_client * client)34 static in_cache_entry *in_cache_get(__be32 dst_ip,
35 struct mpoa_client *client)
36 {
37 in_cache_entry *entry;
38
39 read_lock_bh(&client->ingress_lock);
40 entry = client->in_cache;
41 while (entry != NULL) {
42 if (entry->ctrl_info.in_dst_ip == dst_ip) {
43 atomic_inc(&entry->use);
44 read_unlock_bh(&client->ingress_lock);
45 return entry;
46 }
47 entry = entry->next;
48 }
49 read_unlock_bh(&client->ingress_lock);
50
51 return NULL;
52 }
53
in_cache_get_with_mask(__be32 dst_ip,struct mpoa_client * client,__be32 mask)54 static in_cache_entry *in_cache_get_with_mask(__be32 dst_ip,
55 struct mpoa_client *client,
56 __be32 mask)
57 {
58 in_cache_entry *entry;
59
60 read_lock_bh(&client->ingress_lock);
61 entry = client->in_cache;
62 while (entry != NULL) {
63 if ((entry->ctrl_info.in_dst_ip & mask) == (dst_ip & mask)) {
64 atomic_inc(&entry->use);
65 read_unlock_bh(&client->ingress_lock);
66 return entry;
67 }
68 entry = entry->next;
69 }
70 read_unlock_bh(&client->ingress_lock);
71
72 return NULL;
73
74 }
75
in_cache_get_by_vcc(struct atm_vcc * vcc,struct mpoa_client * client)76 static in_cache_entry *in_cache_get_by_vcc(struct atm_vcc *vcc,
77 struct mpoa_client *client)
78 {
79 in_cache_entry *entry;
80
81 read_lock_bh(&client->ingress_lock);
82 entry = client->in_cache;
83 while (entry != NULL) {
84 if (entry->shortcut == vcc) {
85 atomic_inc(&entry->use);
86 read_unlock_bh(&client->ingress_lock);
87 return entry;
88 }
89 entry = entry->next;
90 }
91 read_unlock_bh(&client->ingress_lock);
92
93 return NULL;
94 }
95
in_cache_add_entry(__be32 dst_ip,struct mpoa_client * client)96 static in_cache_entry *in_cache_add_entry(__be32 dst_ip,
97 struct mpoa_client *client)
98 {
99 in_cache_entry *entry = kzalloc(sizeof(in_cache_entry), GFP_KERNEL);
100
101 if (entry == NULL) {
102 pr_info("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n");
103 return NULL;
104 }
105
106 dprintk("adding an ingress entry, ip = %pI4\n", &dst_ip);
107
108 atomic_set(&entry->use, 1);
109 dprintk("new_in_cache_entry: about to lock\n");
110 write_lock_bh(&client->ingress_lock);
111 entry->next = client->in_cache;
112 entry->prev = NULL;
113 if (client->in_cache != NULL)
114 client->in_cache->prev = entry;
115 client->in_cache = entry;
116
117 memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
118 entry->ctrl_info.in_dst_ip = dst_ip;
119 do_gettimeofday(&(entry->tv));
120 entry->retry_time = client->parameters.mpc_p4;
121 entry->count = 1;
122 entry->entry_state = INGRESS_INVALID;
123 entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT;
124 atomic_inc(&entry->use);
125
126 write_unlock_bh(&client->ingress_lock);
127 dprintk("new_in_cache_entry: unlocked\n");
128
129 return entry;
130 }
131
cache_hit(in_cache_entry * entry,struct mpoa_client * mpc)132 static int cache_hit(in_cache_entry *entry, struct mpoa_client *mpc)
133 {
134 struct atm_mpoa_qos *qos;
135 struct k_message msg;
136
137 entry->count++;
138 if (entry->entry_state == INGRESS_RESOLVED && entry->shortcut != NULL)
139 return OPEN;
140
141 if (entry->entry_state == INGRESS_REFRESHING) {
142 if (entry->count > mpc->parameters.mpc_p1) {
143 msg.type = SND_MPOA_RES_RQST;
144 msg.content.in_info = entry->ctrl_info;
145 memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN);
146 qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
147 if (qos != NULL)
148 msg.qos = qos->qos;
149 msg_to_mpoad(&msg, mpc);
150 do_gettimeofday(&(entry->reply_wait));
151 entry->entry_state = INGRESS_RESOLVING;
152 }
153 if (entry->shortcut != NULL)
154 return OPEN;
155 return CLOSED;
156 }
157
158 if (entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL)
159 return OPEN;
160
161 if (entry->count > mpc->parameters.mpc_p1 &&
162 entry->entry_state == INGRESS_INVALID) {
163 dprintk("(%s) threshold exceeded for ip %pI4, sending MPOA res req\n",
164 mpc->dev->name, &entry->ctrl_info.in_dst_ip);
165 entry->entry_state = INGRESS_RESOLVING;
166 msg.type = SND_MPOA_RES_RQST;
167 memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN);
168 msg.content.in_info = entry->ctrl_info;
169 qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
170 if (qos != NULL)
171 msg.qos = qos->qos;
172 msg_to_mpoad(&msg, mpc);
173 do_gettimeofday(&(entry->reply_wait));
174 }
175
176 return CLOSED;
177 }
178
in_cache_put(in_cache_entry * entry)179 static void in_cache_put(in_cache_entry *entry)
180 {
181 if (atomic_dec_and_test(&entry->use)) {
182 memset(entry, 0, sizeof(in_cache_entry));
183 kfree(entry);
184 }
185 }
186
187 /*
188 * This should be called with write lock on
189 */
in_cache_remove_entry(in_cache_entry * entry,struct mpoa_client * client)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, 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, -EPIPE);
221 }
222 }
223
224 /* Call this every MPC-p2 seconds... Not exactly correct solution,
225 but an easy one... */
clear_count_and_expired(struct mpoa_client * client)226 static void clear_count_and_expired(struct mpoa_client *client)
227 {
228 in_cache_entry *entry, *next_entry;
229 struct timeval now;
230
231 do_gettimeofday(&now);
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.tv_sec - entry->tv.tv_sec)
239 > entry->ctrl_info.holding_time) {
240 dprintk("holding time expired, ip = %pI4\n",
241 &entry->ctrl_info.in_dst_ip);
242 client->in_ops->remove_entry(entry, client);
243 }
244 entry = next_entry;
245 }
246 write_unlock_bh(&client->ingress_lock);
247 }
248
249 /* Call this every MPC-p4 seconds. */
check_resolving_entries(struct mpoa_client * client)250 static void check_resolving_entries(struct mpoa_client *client)
251 {
252
253 struct atm_mpoa_qos *qos;
254 in_cache_entry *entry;
255 struct timeval now;
256 struct k_message msg;
257
258 do_gettimeofday(&now);
259
260 read_lock_bh(&client->ingress_lock);
261 entry = client->in_cache;
262 while (entry != NULL) {
263 if (entry->entry_state == INGRESS_RESOLVING) {
264 if ((now.tv_sec - entry->hold_down.tv_sec) <
265 client->parameters.mpc_p6) {
266 entry = entry->next; /* Entry in hold down */
267 continue;
268 }
269 if ((now.tv_sec - entry->reply_wait.tv_sec) >
270 entry->retry_time) {
271 entry->retry_time = MPC_C1 * (entry->retry_time);
272 /*
273 * Retry time maximum exceeded,
274 * put entry in hold down.
275 */
276 if (entry->retry_time > client->parameters.mpc_p5) {
277 do_gettimeofday(&(entry->hold_down));
278 entry->retry_time = client->parameters.mpc_p4;
279 entry = entry->next;
280 continue;
281 }
282 /* Ask daemon to send a resolution request. */
283 memset(&(entry->hold_down), 0, sizeof(struct timeval));
284 msg.type = SND_MPOA_RES_RTRY;
285 memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN);
286 msg.content.in_info = entry->ctrl_info;
287 qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
288 if (qos != NULL)
289 msg.qos = qos->qos;
290 msg_to_mpoad(&msg, client);
291 do_gettimeofday(&(entry->reply_wait));
292 }
293 }
294 entry = entry->next;
295 }
296 read_unlock_bh(&client->ingress_lock);
297 }
298
299 /* Call this every MPC-p5 seconds. */
refresh_entries(struct mpoa_client * client)300 static void refresh_entries(struct mpoa_client *client)
301 {
302 struct timeval now;
303 struct in_cache_entry *entry = client->in_cache;
304
305 ddprintk("refresh_entries\n");
306 do_gettimeofday(&now);
307
308 read_lock_bh(&client->ingress_lock);
309 while (entry != NULL) {
310 if (entry->entry_state == INGRESS_RESOLVED) {
311 if (!(entry->refresh_time))
312 entry->refresh_time = (2 * (entry->ctrl_info.holding_time))/3;
313 if ((now.tv_sec - entry->reply_wait.tv_sec) >
314 entry->refresh_time) {
315 dprintk("refreshing an entry.\n");
316 entry->entry_state = INGRESS_REFRESHING;
317
318 }
319 }
320 entry = entry->next;
321 }
322 read_unlock_bh(&client->ingress_lock);
323 }
324
in_destroy_cache(struct mpoa_client * mpc)325 static void in_destroy_cache(struct mpoa_client *mpc)
326 {
327 write_lock_irq(&mpc->ingress_lock);
328 while (mpc->in_cache != NULL)
329 mpc->in_ops->remove_entry(mpc->in_cache, mpc);
330 write_unlock_irq(&mpc->ingress_lock);
331 }
332
eg_cache_get_by_cache_id(__be32 cache_id,struct mpoa_client * mpc)333 static eg_cache_entry *eg_cache_get_by_cache_id(__be32 cache_id,
334 struct mpoa_client *mpc)
335 {
336 eg_cache_entry *entry;
337
338 read_lock_irq(&mpc->egress_lock);
339 entry = mpc->eg_cache;
340 while (entry != NULL) {
341 if (entry->ctrl_info.cache_id == cache_id) {
342 atomic_inc(&entry->use);
343 read_unlock_irq(&mpc->egress_lock);
344 return entry;
345 }
346 entry = entry->next;
347 }
348 read_unlock_irq(&mpc->egress_lock);
349
350 return NULL;
351 }
352
353 /* This can be called from any context since it saves CPU flags */
eg_cache_get_by_tag(__be32 tag,struct mpoa_client * mpc)354 static eg_cache_entry *eg_cache_get_by_tag(__be32 tag, struct mpoa_client *mpc)
355 {
356 unsigned long flags;
357 eg_cache_entry *entry;
358
359 read_lock_irqsave(&mpc->egress_lock, flags);
360 entry = mpc->eg_cache;
361 while (entry != NULL) {
362 if (entry->ctrl_info.tag == tag) {
363 atomic_inc(&entry->use);
364 read_unlock_irqrestore(&mpc->egress_lock, flags);
365 return entry;
366 }
367 entry = entry->next;
368 }
369 read_unlock_irqrestore(&mpc->egress_lock, flags);
370
371 return NULL;
372 }
373
374 /* This can be called from any context since it saves CPU flags */
eg_cache_get_by_vcc(struct atm_vcc * vcc,struct mpoa_client * mpc)375 static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc,
376 struct mpoa_client *mpc)
377 {
378 unsigned long flags;
379 eg_cache_entry *entry;
380
381 read_lock_irqsave(&mpc->egress_lock, flags);
382 entry = mpc->eg_cache;
383 while (entry != NULL) {
384 if (entry->shortcut == vcc) {
385 atomic_inc(&entry->use);
386 read_unlock_irqrestore(&mpc->egress_lock, flags);
387 return entry;
388 }
389 entry = entry->next;
390 }
391 read_unlock_irqrestore(&mpc->egress_lock, flags);
392
393 return NULL;
394 }
395
eg_cache_get_by_src_ip(__be32 ipaddr,struct mpoa_client * mpc)396 static eg_cache_entry *eg_cache_get_by_src_ip(__be32 ipaddr,
397 struct mpoa_client *mpc)
398 {
399 eg_cache_entry *entry;
400
401 read_lock_irq(&mpc->egress_lock);
402 entry = mpc->eg_cache;
403 while (entry != NULL) {
404 if (entry->latest_ip_addr == ipaddr) {
405 atomic_inc(&entry->use);
406 read_unlock_irq(&mpc->egress_lock);
407 return entry;
408 }
409 entry = entry->next;
410 }
411 read_unlock_irq(&mpc->egress_lock);
412
413 return NULL;
414 }
415
eg_cache_put(eg_cache_entry * entry)416 static void eg_cache_put(eg_cache_entry *entry)
417 {
418 if (atomic_dec_and_test(&entry->use)) {
419 memset(entry, 0, sizeof(eg_cache_entry));
420 kfree(entry);
421 }
422 }
423
424 /*
425 * This should be called with write lock on
426 */
eg_cache_remove_entry(eg_cache_entry * entry,struct mpoa_client * client)427 static void eg_cache_remove_entry(eg_cache_entry *entry,
428 struct mpoa_client *client)
429 {
430 struct atm_vcc *vcc;
431 struct k_message msg;
432
433 vcc = entry->shortcut;
434 dprintk("removing an egress entry.\n");
435 if (entry->prev != NULL)
436 entry->prev->next = entry->next;
437 else
438 client->eg_cache = entry->next;
439 if (entry->next != NULL)
440 entry->next->prev = entry->prev;
441 client->eg_ops->put(entry);
442 if (client->in_cache == NULL && client->eg_cache == NULL) {
443 msg.type = STOP_KEEP_ALIVE_SM;
444 msg_to_mpoad(&msg, client);
445 }
446
447 /* Check if the ingress side still uses this VCC */
448 if (vcc != NULL) {
449 in_cache_entry *in_entry = client->in_ops->get_by_vcc(vcc, client);
450 if (in_entry != NULL) {
451 client->in_ops->put(in_entry);
452 return;
453 }
454 vcc_release_async(vcc, -EPIPE);
455 }
456 }
457
eg_cache_add_entry(struct k_message * msg,struct mpoa_client * client)458 static eg_cache_entry *eg_cache_add_entry(struct k_message *msg,
459 struct mpoa_client *client)
460 {
461 eg_cache_entry *entry = kzalloc(sizeof(eg_cache_entry), GFP_KERNEL);
462
463 if (entry == NULL) {
464 pr_info("out of memory\n");
465 return NULL;
466 }
467
468 dprintk("adding an egress entry, ip = %pI4, this should be our IP\n",
469 &msg->content.eg_info.eg_dst_ip);
470
471 atomic_set(&entry->use, 1);
472 dprintk("new_eg_cache_entry: about to lock\n");
473 write_lock_irq(&client->egress_lock);
474 entry->next = client->eg_cache;
475 entry->prev = NULL;
476 if (client->eg_cache != NULL)
477 client->eg_cache->prev = entry;
478 client->eg_cache = entry;
479
480 memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
481 entry->ctrl_info = msg->content.eg_info;
482 do_gettimeofday(&(entry->tv));
483 entry->entry_state = EGRESS_RESOLVED;
484 dprintk("new_eg_cache_entry cache_id %u\n",
485 ntohl(entry->ctrl_info.cache_id));
486 dprintk("mps_ip = %pI4\n", &entry->ctrl_info.mps_ip);
487 atomic_inc(&entry->use);
488
489 write_unlock_irq(&client->egress_lock);
490 dprintk("new_eg_cache_entry: unlocked\n");
491
492 return entry;
493 }
494
update_eg_cache_entry(eg_cache_entry * entry,uint16_t holding_time)495 static void update_eg_cache_entry(eg_cache_entry *entry, uint16_t holding_time)
496 {
497 do_gettimeofday(&(entry->tv));
498 entry->entry_state = EGRESS_RESOLVED;
499 entry->ctrl_info.holding_time = holding_time;
500 }
501
clear_expired(struct mpoa_client * client)502 static void clear_expired(struct mpoa_client *client)
503 {
504 eg_cache_entry *entry, *next_entry;
505 struct timeval now;
506 struct k_message msg;
507
508 do_gettimeofday(&now);
509
510 write_lock_irq(&client->egress_lock);
511 entry = client->eg_cache;
512 while (entry != NULL) {
513 next_entry = entry->next;
514 if ((now.tv_sec - entry->tv.tv_sec)
515 > entry->ctrl_info.holding_time) {
516 msg.type = SND_EGRESS_PURGE;
517 msg.content.eg_info = entry->ctrl_info;
518 dprintk("egress_cache: holding time expired, cache_id = %u.\n",
519 ntohl(entry->ctrl_info.cache_id));
520 msg_to_mpoad(&msg, client);
521 client->eg_ops->remove_entry(entry, client);
522 }
523 entry = next_entry;
524 }
525 write_unlock_irq(&client->egress_lock);
526 }
527
eg_destroy_cache(struct mpoa_client * mpc)528 static void eg_destroy_cache(struct mpoa_client *mpc)
529 {
530 write_lock_irq(&mpc->egress_lock);
531 while (mpc->eg_cache != NULL)
532 mpc->eg_ops->remove_entry(mpc->eg_cache, mpc);
533 write_unlock_irq(&mpc->egress_lock);
534 }
535
536
537 static struct in_cache_ops ingress_ops = {
538 in_cache_add_entry, /* add_entry */
539 in_cache_get, /* get */
540 in_cache_get_with_mask, /* get_with_mask */
541 in_cache_get_by_vcc, /* get_by_vcc */
542 in_cache_put, /* put */
543 in_cache_remove_entry, /* remove_entry */
544 cache_hit, /* cache_hit */
545 clear_count_and_expired, /* clear_count */
546 check_resolving_entries, /* check_resolving */
547 refresh_entries, /* refresh */
548 in_destroy_cache /* destroy_cache */
549 };
550
551 static struct eg_cache_ops egress_ops = {
552 eg_cache_add_entry, /* add_entry */
553 eg_cache_get_by_cache_id, /* get_by_cache_id */
554 eg_cache_get_by_tag, /* get_by_tag */
555 eg_cache_get_by_vcc, /* get_by_vcc */
556 eg_cache_get_by_src_ip, /* get_by_src_ip */
557 eg_cache_put, /* put */
558 eg_cache_remove_entry, /* remove_entry */
559 update_eg_cache_entry, /* update */
560 clear_expired, /* clear_expired */
561 eg_destroy_cache /* destroy_cache */
562 };
563
564
atm_mpoa_init_cache(struct mpoa_client * mpc)565 void atm_mpoa_init_cache(struct mpoa_client *mpc)
566 {
567 mpc->in_ops = &ingress_ops;
568 mpc->eg_ops = &egress_ops;
569 }
570