Merge git://git.infradead.org/~dwmw2/cafe-2.6
[linux-2.6] / net / atm / mpoa_caches.c
1 #include <linux/types.h>
2 #include <linux/atmmpc.h>
3 #include <linux/time.h>
4
5 #include "mpoa_caches.h"
6 #include "mpc.h"
7
8 /*
9  * mpoa_caches.c: Implementation of ingress and egress cache
10  * handling functions
11  */
12
13 #if 0
14 #define dprintk printk    /* debug */
15 #else
16 #define dprintk(format,args...)
17 #endif
18
19 #if 0
20 #define ddprintk printk  /* more debug */
21 #else
22 #define ddprintk(format,args...)
23 #endif
24
25 static in_cache_entry *in_cache_get(uint32_t dst_ip,
26                                     struct mpoa_client *client)
27 {
28         in_cache_entry *entry;
29
30         read_lock_bh(&client->ingress_lock);
31         entry = client->in_cache;
32         while(entry != NULL){
33                 if( entry->ctrl_info.in_dst_ip == dst_ip ){
34                         atomic_inc(&entry->use);
35                         read_unlock_bh(&client->ingress_lock);
36                         return entry;
37                 }
38                 entry = entry->next;
39         }
40         read_unlock_bh(&client->ingress_lock);
41
42         return NULL;
43 }
44
45 static in_cache_entry *in_cache_get_with_mask(uint32_t dst_ip,
46                                               struct mpoa_client *client,
47                                               uint32_t mask)
48 {
49         in_cache_entry *entry;
50
51         read_lock_bh(&client->ingress_lock);
52         entry = client->in_cache;
53         while(entry != NULL){
54                 if((entry->ctrl_info.in_dst_ip & mask)  == (dst_ip & mask )){
55                         atomic_inc(&entry->use);
56                         read_unlock_bh(&client->ingress_lock);
57                         return entry;
58                 }
59                 entry = entry->next;
60         }
61         read_unlock_bh(&client->ingress_lock);
62
63         return NULL;
64
65 }
66
67 static in_cache_entry *in_cache_get_by_vcc(struct atm_vcc *vcc,
68                                            struct mpoa_client *client )
69 {
70         in_cache_entry *entry;
71
72         read_lock_bh(&client->ingress_lock);
73         entry = client->in_cache;
74         while(entry != NULL){
75                 if(entry->shortcut == vcc) {
76                         atomic_inc(&entry->use);
77                         read_unlock_bh(&client->ingress_lock);
78                         return entry;
79                 }
80                 entry = entry->next;
81         }
82         read_unlock_bh(&client->ingress_lock);
83
84         return NULL;
85 }
86
87 static in_cache_entry *in_cache_add_entry(uint32_t dst_ip,
88                                           struct mpoa_client *client)
89 {
90         in_cache_entry* entry = kmalloc(sizeof(in_cache_entry), GFP_KERNEL);
91
92         if (entry == NULL) {
93                 printk("mpoa: mpoa_caches.c: new_in_cache_entry: out of memory\n");
94                 return NULL;
95         }
96
97         dprintk("mpoa: mpoa_caches.c: adding an ingress entry, ip = %u.%u.%u.%u\n", NIPQUAD(dst_ip));
98         memset(entry,0,sizeof(in_cache_entry));
99
100         atomic_set(&entry->use, 1);
101         dprintk("mpoa: mpoa_caches.c: new_in_cache_entry: about to lock\n");
102         write_lock_bh(&client->ingress_lock);
103         entry->next = client->in_cache;
104         entry->prev = NULL;
105         if (client->in_cache != NULL)
106                 client->in_cache->prev = entry;
107         client->in_cache = entry;
108
109         memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
110         entry->ctrl_info.in_dst_ip = dst_ip;
111         do_gettimeofday(&(entry->tv));
112         entry->retry_time = client->parameters.mpc_p4;
113         entry->count = 1;
114         entry->entry_state = INGRESS_INVALID;
115         entry->ctrl_info.holding_time = HOLDING_TIME_DEFAULT;
116         atomic_inc(&entry->use);
117
118         write_unlock_bh(&client->ingress_lock);
119         dprintk("mpoa: mpoa_caches.c: new_in_cache_entry: unlocked\n");
120
121         return entry;
122 }
123
124 static int cache_hit(in_cache_entry *entry, struct mpoa_client *mpc)
125 {
126         struct atm_mpoa_qos *qos;
127         struct k_message msg;
128
129         entry->count++;
130         if(entry->entry_state == INGRESS_RESOLVED && entry->shortcut != NULL)
131                 return OPEN;
132
133         if(entry->entry_state == INGRESS_REFRESHING){
134                 if(entry->count > mpc->parameters.mpc_p1){
135                         msg.type = SND_MPOA_RES_RQST;
136                         msg.content.in_info = entry->ctrl_info;
137                         memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN);
138                         qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
139                         if (qos != NULL) msg.qos = qos->qos;
140                         msg_to_mpoad(&msg, mpc);
141                         do_gettimeofday(&(entry->reply_wait));
142                         entry->entry_state = INGRESS_RESOLVING;
143                 }
144                 if(entry->shortcut != NULL)
145                         return OPEN;
146                 return CLOSED;
147         }
148
149         if(entry->entry_state == INGRESS_RESOLVING && entry->shortcut != NULL)
150                 return OPEN;
151
152         if( entry->count > mpc->parameters.mpc_p1 &&
153             entry->entry_state == INGRESS_INVALID){
154                 dprintk("mpoa: (%s) mpoa_caches.c: threshold exceeded for ip %u.%u.%u.%u, sending MPOA res req\n", mpc->dev->name, NIPQUAD(entry->ctrl_info.in_dst_ip));
155                 entry->entry_state = INGRESS_RESOLVING;
156                 msg.type =  SND_MPOA_RES_RQST;
157                 memcpy(msg.MPS_ctrl, mpc->mps_ctrl_addr, ATM_ESA_LEN );
158                 msg.content.in_info = entry->ctrl_info;
159                 qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
160                 if (qos != NULL) msg.qos = qos->qos;
161                 msg_to_mpoad( &msg, mpc);
162                 do_gettimeofday(&(entry->reply_wait));
163         }
164
165         return CLOSED;
166 }
167
168 static void in_cache_put(in_cache_entry *entry)
169 {
170         if (atomic_dec_and_test(&entry->use)) {
171                 memset(entry, 0, sizeof(in_cache_entry));
172                 kfree(entry);
173         }
174
175         return;
176 }
177
178 /*
179  * This should be called with write lock on
180  */
181 static void in_cache_remove_entry(in_cache_entry *entry,
182                                   struct mpoa_client *client)
183 {
184         struct atm_vcc *vcc;
185         struct k_message msg;
186
187         vcc = entry->shortcut;
188         dprintk("mpoa: mpoa_caches.c: removing an ingress entry, ip = %u.%u.%u.%u\n",NIPQUAD(entry->ctrl_info.in_dst_ip));
189
190         if (entry->prev != NULL)
191                 entry->prev->next = entry->next;
192         else
193                 client->in_cache = entry->next;
194         if (entry->next != NULL)
195                 entry->next->prev = entry->prev;
196         client->in_ops->put(entry);
197         if(client->in_cache == NULL && client->eg_cache == NULL){
198                 msg.type = STOP_KEEP_ALIVE_SM;
199                 msg_to_mpoad(&msg,client);
200         }
201
202         /* Check if the egress side still uses this VCC */
203         if (vcc != NULL) {
204                 eg_cache_entry *eg_entry = client->eg_ops->get_by_vcc(vcc, client);
205                 if (eg_entry != NULL) {
206                         client->eg_ops->put(eg_entry);
207                         return;
208                 }
209                 vcc_release_async(vcc, -EPIPE);
210         }
211
212         return;
213 }
214
215
216 /* Call this every MPC-p2 seconds... Not exactly correct solution,
217    but an easy one... */
218 static void clear_count_and_expired(struct mpoa_client *client)
219 {
220         in_cache_entry *entry, *next_entry;
221         struct timeval now;
222
223         do_gettimeofday(&now);
224
225         write_lock_bh(&client->ingress_lock);
226         entry = client->in_cache;
227         while(entry != NULL){
228                 entry->count=0;
229                 next_entry = entry->next;
230                 if((now.tv_sec - entry->tv.tv_sec)
231                    > entry->ctrl_info.holding_time){
232                         dprintk("mpoa: mpoa_caches.c: holding time expired, ip = %u.%u.%u.%u\n", NIPQUAD(entry->ctrl_info.in_dst_ip));
233                         client->in_ops->remove_entry(entry, client);
234                 }
235                 entry = next_entry;
236         }
237         write_unlock_bh(&client->ingress_lock);
238
239         return;
240 }
241
242 /* Call this every MPC-p4 seconds. */
243 static void check_resolving_entries(struct mpoa_client *client)
244 {
245
246         struct atm_mpoa_qos *qos;
247         in_cache_entry *entry;
248         struct timeval now;
249         struct k_message msg;
250
251         do_gettimeofday( &now );
252
253         read_lock_bh(&client->ingress_lock);
254         entry = client->in_cache;
255         while( entry != NULL ){
256                 if(entry->entry_state == INGRESS_RESOLVING){
257                         if(now.tv_sec - entry->hold_down.tv_sec < client->parameters.mpc_p6){
258                                 entry = entry->next;                      /* Entry in hold down */
259                                 continue;
260                         }
261                         if( (now.tv_sec - entry->reply_wait.tv_sec) >
262                             entry->retry_time ){
263                                 entry->retry_time = MPC_C1*( entry->retry_time );
264                                 if(entry->retry_time > client->parameters.mpc_p5){
265                                         /* Retry time maximum exceeded, put entry in hold down. */
266                                         do_gettimeofday(&(entry->hold_down));
267                                         entry->retry_time = client->parameters.mpc_p4;
268                                         entry = entry->next;
269                                         continue;
270                                 }
271                                 /* Ask daemon to send a resolution request. */
272                                 memset(&(entry->hold_down),0,sizeof(struct timeval));
273                                 msg.type = SND_MPOA_RES_RTRY;
274                                 memcpy(msg.MPS_ctrl, client->mps_ctrl_addr, ATM_ESA_LEN);
275                                 msg.content.in_info = entry->ctrl_info;
276                                 qos = atm_mpoa_search_qos(entry->ctrl_info.in_dst_ip);
277                                 if (qos != NULL) msg.qos = qos->qos;
278                                 msg_to_mpoad(&msg, client);
279                                 do_gettimeofday(&(entry->reply_wait));
280                         }
281                 }
282                 entry = entry->next;
283         }
284         read_unlock_bh(&client->ingress_lock);
285 }
286
287 /* Call this every MPC-p5 seconds. */
288 static void refresh_entries(struct mpoa_client *client)
289 {
290         struct timeval now;
291         struct in_cache_entry *entry = client->in_cache;
292
293         ddprintk("mpoa: mpoa_caches.c: refresh_entries\n");
294         do_gettimeofday(&now);
295
296         read_lock_bh(&client->ingress_lock);
297         while( entry != NULL ){
298                 if( entry->entry_state == INGRESS_RESOLVED ){
299                         if(!(entry->refresh_time))
300                                 entry->refresh_time = (2*(entry->ctrl_info.holding_time))/3;
301                         if( (now.tv_sec - entry->reply_wait.tv_sec) > entry->refresh_time ){
302                                 dprintk("mpoa: mpoa_caches.c: refreshing an entry.\n");
303                                 entry->entry_state = INGRESS_REFRESHING;
304
305                         }
306                 }
307                 entry = entry->next;
308         }
309         read_unlock_bh(&client->ingress_lock);
310 }
311
312 static void in_destroy_cache(struct mpoa_client *mpc)
313 {
314         write_lock_irq(&mpc->ingress_lock);
315         while(mpc->in_cache != NULL)
316                 mpc->in_ops->remove_entry(mpc->in_cache, mpc);
317         write_unlock_irq(&mpc->ingress_lock);
318
319         return;
320 }
321
322 static eg_cache_entry *eg_cache_get_by_cache_id(uint32_t cache_id, struct mpoa_client *mpc)
323 {
324         eg_cache_entry *entry;
325
326         read_lock_irq(&mpc->egress_lock);
327         entry = mpc->eg_cache;
328         while(entry != NULL){
329                 if(entry->ctrl_info.cache_id == cache_id){
330                         atomic_inc(&entry->use);
331                         read_unlock_irq(&mpc->egress_lock);
332                         return entry;
333                 }
334                 entry = entry->next;
335         }
336         read_unlock_irq(&mpc->egress_lock);
337
338         return NULL;
339 }
340
341 /* This can be called from any context since it saves CPU flags */
342 static eg_cache_entry *eg_cache_get_by_tag(uint32_t tag, struct mpoa_client *mpc)
343 {
344         unsigned long flags;
345         eg_cache_entry *entry;
346
347         read_lock_irqsave(&mpc->egress_lock, flags);
348         entry = mpc->eg_cache;
349         while (entry != NULL){
350                 if (entry->ctrl_info.tag == tag) {
351                         atomic_inc(&entry->use);
352                         read_unlock_irqrestore(&mpc->egress_lock, flags);
353                         return entry;
354                 }
355                 entry = entry->next;
356         }
357         read_unlock_irqrestore(&mpc->egress_lock, flags);
358
359         return NULL;
360 }
361
362 /* This can be called from any context since it saves CPU flags */
363 static eg_cache_entry *eg_cache_get_by_vcc(struct atm_vcc *vcc, struct mpoa_client *mpc)
364 {
365         unsigned long flags;
366         eg_cache_entry *entry;
367
368         read_lock_irqsave(&mpc->egress_lock, flags);
369         entry = mpc->eg_cache;
370         while (entry != NULL){
371                 if (entry->shortcut == vcc) {
372                         atomic_inc(&entry->use);
373                         read_unlock_irqrestore(&mpc->egress_lock, flags);
374                         return entry;
375                 }
376                 entry = entry->next;
377         }
378         read_unlock_irqrestore(&mpc->egress_lock, flags);
379
380         return NULL;
381 }
382
383 static eg_cache_entry *eg_cache_get_by_src_ip(uint32_t ipaddr, struct mpoa_client *mpc)
384 {
385         eg_cache_entry *entry;
386
387         read_lock_irq(&mpc->egress_lock);
388         entry = mpc->eg_cache;
389         while(entry != NULL){
390                 if(entry->latest_ip_addr == ipaddr) {
391                         atomic_inc(&entry->use);
392                         read_unlock_irq(&mpc->egress_lock);
393                         return entry;
394                 }
395                 entry = entry->next;
396         }
397         read_unlock_irq(&mpc->egress_lock);
398
399         return NULL;
400 }
401
402 static void eg_cache_put(eg_cache_entry *entry)
403 {
404         if (atomic_dec_and_test(&entry->use)) {
405                 memset(entry, 0, sizeof(eg_cache_entry));
406                 kfree(entry);
407         }
408
409         return;
410 }
411
412 /*
413  * This should be called with write lock on
414  */
415 static void eg_cache_remove_entry(eg_cache_entry *entry,
416                                   struct mpoa_client *client)
417 {
418         struct atm_vcc *vcc;
419         struct k_message msg;
420
421         vcc = entry->shortcut;
422         dprintk("mpoa: mpoa_caches.c: removing an egress entry.\n");
423         if (entry->prev != NULL)
424                 entry->prev->next = entry->next;
425         else
426                 client->eg_cache = entry->next;
427         if (entry->next != NULL)
428                 entry->next->prev = entry->prev;
429         client->eg_ops->put(entry);
430         if(client->in_cache == NULL && client->eg_cache == NULL){
431                 msg.type = STOP_KEEP_ALIVE_SM;
432                 msg_to_mpoad(&msg,client);
433         }
434
435         /* Check if the ingress side still uses this VCC */
436         if (vcc != NULL) {
437                 in_cache_entry *in_entry = client->in_ops->get_by_vcc(vcc, client);
438                 if (in_entry != NULL) {
439                         client->in_ops->put(in_entry);
440                         return;
441                 }
442                 vcc_release_async(vcc, -EPIPE);
443         }
444
445         return;
446 }
447
448 static eg_cache_entry *eg_cache_add_entry(struct k_message *msg, struct mpoa_client *client)
449 {
450         eg_cache_entry *entry = kmalloc(sizeof(eg_cache_entry), GFP_KERNEL);
451
452         if (entry == NULL) {
453                 printk("mpoa: mpoa_caches.c: new_eg_cache_entry: out of memory\n");
454                 return NULL;
455         }
456
457         dprintk("mpoa: mpoa_caches.c: adding an egress entry, ip = %u.%u.%u.%u, this should be our IP\n", NIPQUAD(msg->content.eg_info.eg_dst_ip));
458         memset(entry, 0, sizeof(eg_cache_entry));
459
460         atomic_set(&entry->use, 1);
461         dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry: about to lock\n");
462         write_lock_irq(&client->egress_lock);
463         entry->next = client->eg_cache;
464         entry->prev = NULL;
465         if (client->eg_cache != NULL)
466                 client->eg_cache->prev = entry;
467         client->eg_cache = entry;
468
469         memcpy(entry->MPS_ctrl_ATM_addr, client->mps_ctrl_addr, ATM_ESA_LEN);
470         entry->ctrl_info = msg->content.eg_info;
471         do_gettimeofday(&(entry->tv));
472         entry->entry_state = EGRESS_RESOLVED;
473         dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry cache_id %lu\n", ntohl(entry->ctrl_info.cache_id));
474         dprintk("mpoa: mpoa_caches.c: mps_ip = %u.%u.%u.%u\n",
475                 NIPQUAD(entry->ctrl_info.mps_ip));
476         atomic_inc(&entry->use);
477
478         write_unlock_irq(&client->egress_lock);
479         dprintk("mpoa: mpoa_caches.c: new_eg_cache_entry: unlocked\n");
480
481         return entry;
482 }
483
484 static void update_eg_cache_entry(eg_cache_entry * entry, uint16_t holding_time)
485 {
486         do_gettimeofday(&(entry->tv));
487         entry->entry_state = EGRESS_RESOLVED;
488         entry->ctrl_info.holding_time = holding_time;
489
490         return;
491 }
492
493 static void clear_expired(struct mpoa_client *client)
494 {
495         eg_cache_entry *entry, *next_entry;
496         struct timeval now;
497         struct k_message msg;
498
499         do_gettimeofday(&now);
500
501         write_lock_irq(&client->egress_lock);
502         entry = client->eg_cache;
503         while(entry != NULL){
504                 next_entry = entry->next;
505                 if((now.tv_sec - entry->tv.tv_sec)
506                    > entry->ctrl_info.holding_time){
507                         msg.type = SND_EGRESS_PURGE;
508                         msg.content.eg_info = entry->ctrl_info;
509                         dprintk("mpoa: mpoa_caches.c: egress_cache: holding time expired, cache_id = %lu.\n",ntohl(entry->ctrl_info.cache_id));
510                         msg_to_mpoad(&msg, client);
511                         client->eg_ops->remove_entry(entry, client);
512                 }
513                 entry = next_entry;
514         }
515         write_unlock_irq(&client->egress_lock);
516
517         return;
518 }
519
520 static void eg_destroy_cache(struct mpoa_client *mpc)
521 {
522         write_lock_irq(&mpc->egress_lock);
523         while(mpc->eg_cache != NULL)
524                 mpc->eg_ops->remove_entry(mpc->eg_cache, mpc);
525         write_unlock_irq(&mpc->egress_lock);
526
527         return;
528 }
529
530
531
532 static struct in_cache_ops ingress_ops = {
533         in_cache_add_entry,               /* add_entry       */
534         in_cache_get,                     /* get             */
535         in_cache_get_with_mask,           /* get_with_mask   */
536         in_cache_get_by_vcc,              /* get_by_vcc      */
537         in_cache_put,                     /* put             */
538         in_cache_remove_entry,            /* remove_entry    */
539         cache_hit,                        /* cache_hit       */
540         clear_count_and_expired,          /* clear_count     */
541         check_resolving_entries,          /* check_resolving */
542         refresh_entries,                  /* refresh         */
543         in_destroy_cache                  /* destroy_cache   */
544 };
545
546 static struct eg_cache_ops egress_ops = {
547         eg_cache_add_entry,               /* add_entry        */
548         eg_cache_get_by_cache_id,         /* get_by_cache_id  */
549         eg_cache_get_by_tag,              /* get_by_tag       */
550         eg_cache_get_by_vcc,              /* get_by_vcc       */
551         eg_cache_get_by_src_ip,           /* get_by_src_ip    */
552         eg_cache_put,                     /* put              */
553         eg_cache_remove_entry,            /* remove_entry     */
554         update_eg_cache_entry,            /* update           */
555         clear_expired,                    /* clear_expired    */
556         eg_destroy_cache                  /* destroy_cache    */
557 };
558
559
560 void atm_mpoa_init_cache(struct mpoa_client *mpc)
561 {
562         mpc->in_ops = &ingress_ops;
563         mpc->eg_ops = &egress_ops;
564
565         return;
566 }