1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24
25 #include <sys/systm.h>
26 #include <sys/cmn_err.h>
27 #include <sys/kmem.h>
28 #include <sys/disp.h>
29 #include <sys/id_space.h>
30 #include <sys/atomic.h>
31 #include <rpc/rpc.h>
32 #include <nfs/nfs4.h>
33 #include <nfs/nfs4_db_impl.h>
34 #include <sys/sdt.h>
35
36 static int rfs4_reap_interval = RFS4_REAP_INTERVAL;
37
38 static void rfs4_dbe_reap(rfs4_table_t *, time_t, uint32_t);
39 static void rfs4_dbe_destroy(rfs4_dbe_t *);
40 static rfs4_dbe_t *rfs4_dbe_create(rfs4_table_t *, id_t, rfs4_entry_t);
41 static void rfs4_start_reaper(rfs4_table_t *);
42
43 /*
44 * t_lowat - integer percentage of table entries /etc/system only
45 * t_hiwat - integer percentage of table entries /etc/system only
46 * t_lreap - integer percentage of table reap time mdb or /etc/system
47 * t_hreap - integer percentage of table reap time mdb or /etc/system
48 */
49 uint32_t t_lowat = 50; /* reap at t_lreap when id's in use hit 50% */
50 uint32_t t_hiwat = 75; /* reap at t_hreap when id's in use hit 75% */
51 time_t t_lreap = 50; /* default to 50% of table's reap interval */
52 time_t t_hreap = 10; /* default to 10% of table's reap interval */
53
54 id_t
rfs4_dbe_getid(rfs4_dbe_t * entry)55 rfs4_dbe_getid(rfs4_dbe_t *entry)
56 {
57 return (entry->dbe_id);
58 }
59
60 void
rfs4_dbe_hold(rfs4_dbe_t * entry)61 rfs4_dbe_hold(rfs4_dbe_t *entry)
62 {
63 atomic_inc_32(&entry->dbe_refcnt);
64 }
65
66 /*
67 * rfs4_dbe_rele_nolock only decrements the reference count of the entry.
68 */
69 void
rfs4_dbe_rele_nolock(rfs4_dbe_t * entry)70 rfs4_dbe_rele_nolock(rfs4_dbe_t *entry)
71 {
72 atomic_dec_32(&entry->dbe_refcnt);
73 }
74
75
76 uint32_t
rfs4_dbe_refcnt(rfs4_dbe_t * entry)77 rfs4_dbe_refcnt(rfs4_dbe_t *entry)
78 {
79 return (entry->dbe_refcnt);
80 }
81
82 /*
83 * Mark an entry such that the dbsearch will skip it.
84 * Caller does not want this entry to be found any longer
85 */
86 void
rfs4_dbe_invalidate(rfs4_dbe_t * entry)87 rfs4_dbe_invalidate(rfs4_dbe_t *entry)
88 {
89 entry->dbe_invalid = TRUE;
90 entry->dbe_skipsearch = TRUE;
91 }
92
93 /*
94 * Is this entry invalid?
95 */
96 bool_t
rfs4_dbe_is_invalid(rfs4_dbe_t * entry)97 rfs4_dbe_is_invalid(rfs4_dbe_t *entry)
98 {
99 return (entry->dbe_invalid);
100 }
101
102 time_t
rfs4_dbe_get_timerele(rfs4_dbe_t * entry)103 rfs4_dbe_get_timerele(rfs4_dbe_t *entry)
104 {
105 return (entry->dbe_time_rele);
106 }
107
108 /*
109 * Use these to temporarily hide/unhide a db entry.
110 */
111 void
rfs4_dbe_hide(rfs4_dbe_t * entry)112 rfs4_dbe_hide(rfs4_dbe_t *entry)
113 {
114 rfs4_dbe_lock(entry);
115 entry->dbe_skipsearch = TRUE;
116 rfs4_dbe_unlock(entry);
117 }
118
119 void
rfs4_dbe_unhide(rfs4_dbe_t * entry)120 rfs4_dbe_unhide(rfs4_dbe_t *entry)
121 {
122 rfs4_dbe_lock(entry);
123 entry->dbe_skipsearch = FALSE;
124 rfs4_dbe_unlock(entry);
125 }
126
127 void
rfs4_dbe_rele(rfs4_dbe_t * entry)128 rfs4_dbe_rele(rfs4_dbe_t *entry)
129 {
130 mutex_enter(entry->dbe_lock);
131 ASSERT(entry->dbe_refcnt > 1);
132 atomic_dec_32(&entry->dbe_refcnt);
133 entry->dbe_time_rele = gethrestime_sec();
134 mutex_exit(entry->dbe_lock);
135 }
136
137 void
rfs4_dbe_lock(rfs4_dbe_t * entry)138 rfs4_dbe_lock(rfs4_dbe_t *entry)
139 {
140 mutex_enter(entry->dbe_lock);
141 }
142
143 void
rfs4_dbe_unlock(rfs4_dbe_t * entry)144 rfs4_dbe_unlock(rfs4_dbe_t *entry)
145 {
146 mutex_exit(entry->dbe_lock);
147 }
148
149 bool_t
rfs4_dbe_islocked(rfs4_dbe_t * entry)150 rfs4_dbe_islocked(rfs4_dbe_t *entry)
151 {
152 return (mutex_owned(entry->dbe_lock));
153 }
154
155 clock_t
rfs4_dbe_twait(rfs4_dbe_t * entry,clock_t timeout)156 rfs4_dbe_twait(rfs4_dbe_t *entry, clock_t timeout)
157 {
158 return (cv_timedwait(entry->dbe_cv, entry->dbe_lock, timeout));
159 }
160
161 void
rfs4_dbe_cv_broadcast(rfs4_dbe_t * entry)162 rfs4_dbe_cv_broadcast(rfs4_dbe_t *entry)
163 {
164 cv_broadcast(entry->dbe_cv);
165 }
166
167 /* ARGSUSED */
168 static int
rfs4_dbe_kmem_constructor(void * obj,void * private,int kmflag)169 rfs4_dbe_kmem_constructor(void *obj, void *private, int kmflag)
170 {
171 rfs4_dbe_t *entry = obj;
172
173 mutex_init(entry->dbe_lock, NULL, MUTEX_DEFAULT, NULL);
174 cv_init(entry->dbe_cv, NULL, CV_DEFAULT, NULL);
175
176 return (0);
177 }
178
179 static void
rfs4_dbe_kmem_destructor(void * obj,void * private)180 rfs4_dbe_kmem_destructor(void *obj, void *private)
181 {
182 rfs4_dbe_t *entry = obj;
183 /*LINTED*/
184 rfs4_table_t *table = private;
185
186 mutex_destroy(entry->dbe_lock);
187 cv_destroy(entry->dbe_cv);
188 }
189
190 rfs4_database_t *
rfs4_database_create(uint32_t flags)191 rfs4_database_create(uint32_t flags)
192 {
193 rfs4_database_t *db;
194
195 db = kmem_alloc(sizeof (rfs4_database_t), KM_SLEEP);
196 mutex_init(db->db_lock, NULL, MUTEX_DEFAULT, NULL);
197 db->db_tables = NULL;
198 db->db_debug_flags = flags;
199 db->db_shutdown_count = 0;
200 cv_init(&db->db_shutdown_wait, NULL, CV_DEFAULT, NULL);
201 return (db);
202 }
203
204
205 /*
206 * The reaper threads that have been created for the tables in this
207 * database must be stopped and the entries in the tables released.
208 * Each table will be marked as "shutdown" and the reaper threads
209 * poked and they will see that a shutdown is in progress and cleanup
210 * and exit. This function waits for all reaper threads to stop
211 * before returning to the caller.
212 */
213 void
rfs4_database_shutdown(rfs4_database_t * db)214 rfs4_database_shutdown(rfs4_database_t *db)
215 {
216 rfs4_table_t *table;
217
218 mutex_enter(db->db_lock);
219 for (table = db->db_tables; table; table = table->dbt_tnext) {
220 mutex_enter(&table->dbt_reaper_cv_lock);
221 table->dbt_reaper_shutdown = TRUE;
222 cv_broadcast(&table->dbt_reaper_wait);
223 db->db_shutdown_count++;
224 mutex_exit(&table->dbt_reaper_cv_lock);
225 }
226 while (db->db_shutdown_count > 0) {
227 cv_wait(&db->db_shutdown_wait, db->db_lock);
228 }
229 mutex_exit(db->db_lock);
230 }
231
232 /*
233 * Given a database that has been "shutdown" by the function above all
234 * of the table tables are destroyed and then the database itself
235 * freed.
236 */
237 void
rfs4_database_destroy(rfs4_database_t * db)238 rfs4_database_destroy(rfs4_database_t *db)
239 {
240 rfs4_table_t *next, *tmp;
241
242 for (next = db->db_tables; next; ) {
243 tmp = next;
244 next = tmp->dbt_tnext;
245 rfs4_table_destroy(db, tmp);
246 }
247
248 mutex_destroy(db->db_lock);
249 kmem_free(db, sizeof (rfs4_database_t));
250 }
251
252 rfs4_table_t *
rfs4_table_create(rfs4_database_t * db,char * tabname,time_t max_cache_time,uint32_t idxcnt,bool_t (* create)(rfs4_entry_t,void *),void (* destroy)(rfs4_entry_t),bool_t (* expiry)(rfs4_entry_t),uint32_t size,uint32_t hashsize,uint32_t maxentries,id_t start)253 rfs4_table_create(rfs4_database_t *db, char *tabname, time_t max_cache_time,
254 uint32_t idxcnt, bool_t (*create)(rfs4_entry_t, void *),
255 void (*destroy)(rfs4_entry_t),
256 bool_t (*expiry)(rfs4_entry_t),
257 uint32_t size, uint32_t hashsize,
258 uint32_t maxentries, id_t start)
259 {
260 rfs4_table_t *table;
261 int len;
262 char *cache_name;
263 char *id_name;
264
265 table = kmem_alloc(sizeof (rfs4_table_t), KM_SLEEP);
266 table->dbt_db = db;
267 rw_init(table->dbt_t_lock, NULL, RW_DEFAULT, NULL);
268 mutex_init(table->dbt_lock, NULL, MUTEX_DEFAULT, NULL);
269 mutex_init(&table->dbt_reaper_cv_lock, NULL, MUTEX_DEFAULT, NULL);
270 cv_init(&table->dbt_reaper_wait, NULL, CV_DEFAULT, NULL);
271
272 len = strlen(tabname);
273 table->dbt_name = kmem_alloc(len+1, KM_SLEEP);
274 cache_name = kmem_alloc(len + 12 /* "_entry_cache" */ + 1, KM_SLEEP);
275 (void) strcpy(table->dbt_name, tabname);
276 (void) sprintf(cache_name, "%s_entry_cache", table->dbt_name);
277 table->dbt_max_cache_time = max_cache_time;
278 table->dbt_usize = size;
279 table->dbt_len = hashsize;
280 table->dbt_count = 0;
281 table->dbt_idxcnt = 0;
282 table->dbt_ccnt = 0;
283 table->dbt_maxcnt = idxcnt;
284 table->dbt_indices = NULL;
285 table->dbt_id_space = NULL;
286 table->dbt_reaper_shutdown = FALSE;
287
288 if (start >= 0) {
289 if (maxentries + (uint32_t)start > (uint32_t)INT32_MAX)
290 maxentries = INT32_MAX - start;
291 id_name = kmem_alloc(len + 9 /* "_id_space" */ + 1, KM_SLEEP);
292 (void) sprintf(id_name, "%s_id_space", table->dbt_name);
293 table->dbt_id_space = id_space_create(id_name, start,
294 maxentries + start);
295 kmem_free(id_name, len + 10);
296 }
297 ASSERT(t_lowat != 0);
298 table->dbt_id_lwat = (maxentries * t_lowat) / 100;
299 ASSERT(t_hiwat != 0);
300 table->dbt_id_hwat = (maxentries * t_hiwat) / 100;
301 table->dbt_id_reap = MIN(rfs4_reap_interval, max_cache_time);
302 table->dbt_maxentries = maxentries;
303 table->dbt_create = create;
304 table->dbt_destroy = destroy;
305 table->dbt_expiry = expiry;
306
307 table->dbt_mem_cache = kmem_cache_create(cache_name,
308 sizeof (rfs4_dbe_t) + idxcnt * sizeof (rfs4_link_t) + size,
309 0,
310 rfs4_dbe_kmem_constructor,
311 rfs4_dbe_kmem_destructor,
312 NULL,
313 table,
314 NULL,
315 0);
316 kmem_free(cache_name, len+13);
317
318 table->dbt_debug = db->db_debug_flags;
319
320 mutex_enter(db->db_lock);
321 table->dbt_tnext = db->db_tables;
322 db->db_tables = table;
323 mutex_exit(db->db_lock);
324
325 rfs4_start_reaper(table);
326
327 return (table);
328 }
329
330 void
rfs4_table_destroy(rfs4_database_t * db,rfs4_table_t * table)331 rfs4_table_destroy(rfs4_database_t *db, rfs4_table_t *table)
332 {
333 rfs4_table_t *p;
334 rfs4_index_t *idx;
335
336 ASSERT(table->dbt_count == 0);
337
338 mutex_enter(db->db_lock);
339 if (table == db->db_tables)
340 db->db_tables = table->dbt_tnext;
341 else {
342 for (p = db->db_tables; p; p = p->dbt_tnext)
343 if (p->dbt_tnext == table) {
344 p->dbt_tnext = table->dbt_tnext;
345 table->dbt_tnext = NULL;
346 break;
347 }
348 ASSERT(p != NULL);
349 }
350 mutex_exit(db->db_lock);
351
352 /* Destroy indices */
353 while (table->dbt_indices) {
354 idx = table->dbt_indices;
355 table->dbt_indices = idx->dbi_inext;
356 rfs4_index_destroy(idx);
357 }
358
359 rw_destroy(table->dbt_t_lock);
360 mutex_destroy(table->dbt_lock);
361 mutex_destroy(&table->dbt_reaper_cv_lock);
362 cv_destroy(&table->dbt_reaper_wait);
363
364 kmem_free(table->dbt_name, strlen(table->dbt_name) + 1);
365 if (table->dbt_id_space)
366 id_space_destroy(table->dbt_id_space);
367 kmem_cache_destroy(table->dbt_mem_cache);
368 kmem_free(table, sizeof (rfs4_table_t));
369 }
370
371 rfs4_index_t *
rfs4_index_create(rfs4_table_t * table,char * keyname,uint32_t (* hash)(void *),bool_t (compare)(rfs4_entry_t,void *),void * (* mkkey)(rfs4_entry_t),bool_t createable)372 rfs4_index_create(rfs4_table_t *table, char *keyname,
373 uint32_t (*hash)(void *),
374 bool_t (compare)(rfs4_entry_t, void *),
375 void *(*mkkey)(rfs4_entry_t),
376 bool_t createable)
377 {
378 rfs4_index_t *idx;
379
380 ASSERT(table->dbt_idxcnt < table->dbt_maxcnt);
381
382 idx = kmem_alloc(sizeof (rfs4_index_t), KM_SLEEP);
383
384 idx->dbi_table = table;
385 idx->dbi_keyname = kmem_alloc(strlen(keyname) + 1, KM_SLEEP);
386 (void) strcpy(idx->dbi_keyname, keyname);
387 idx->dbi_hash = hash;
388 idx->dbi_compare = compare;
389 idx->dbi_mkkey = mkkey;
390 idx->dbi_tblidx = table->dbt_idxcnt;
391 table->dbt_idxcnt++;
392 if (createable) {
393 table->dbt_ccnt++;
394 if (table->dbt_ccnt > 1)
395 panic("Table %s currently can have only have one "
396 "index that will allow creation of entries",
397 table->dbt_name);
398 idx->dbi_createable = TRUE;
399 } else {
400 idx->dbi_createable = FALSE;
401 }
402
403 idx->dbi_inext = table->dbt_indices;
404 table->dbt_indices = idx;
405 idx->dbi_buckets = kmem_zalloc(sizeof (rfs4_bucket_t) * table->dbt_len,
406 KM_SLEEP);
407
408 return (idx);
409 }
410
411 void
rfs4_index_destroy(rfs4_index_t * idx)412 rfs4_index_destroy(rfs4_index_t *idx)
413 {
414 kmem_free(idx->dbi_keyname, strlen(idx->dbi_keyname) + 1);
415 kmem_free(idx->dbi_buckets,
416 sizeof (rfs4_bucket_t) * idx->dbi_table->dbt_len);
417 kmem_free(idx, sizeof (rfs4_index_t));
418 }
419
420 static void
rfs4_dbe_destroy(rfs4_dbe_t * entry)421 rfs4_dbe_destroy(rfs4_dbe_t *entry)
422 {
423 rfs4_index_t *idx;
424 void *key;
425 int i;
426 rfs4_bucket_t *bp;
427 rfs4_table_t *table = entry->dbe_table;
428 rfs4_link_t *l;
429
430 NFS4_DEBUG(table->dbt_debug & DESTROY_DEBUG,
431 (CE_NOTE, "Destroying entry %p from %s",
432 (void*)entry, table->dbt_name));
433
434 mutex_enter(entry->dbe_lock);
435 ASSERT(entry->dbe_refcnt == 0);
436 mutex_exit(entry->dbe_lock);
437
438 /* Unlink from all indices */
439 for (idx = table->dbt_indices; idx; idx = idx->dbi_inext) {
440 l = &entry->dbe_indices[idx->dbi_tblidx];
441 /* check and see if we were ever linked in to the index */
442 if (INVALID_LINK(l)) {
443 ASSERT(l->next == NULL && l->prev == NULL);
444 continue;
445 }
446 key = idx->dbi_mkkey(entry->dbe_data);
447 i = HASH(idx, key);
448 bp = &idx->dbi_buckets[i];
449 ASSERT(bp->dbk_head != NULL);
450 DEQUEUE_IDX(bp, &entry->dbe_indices[idx->dbi_tblidx]);
451 }
452
453 /* Destroy user data */
454 if (table->dbt_destroy)
455 (*table->dbt_destroy)(entry->dbe_data);
456
457 if (table->dbt_id_space)
458 id_free(table->dbt_id_space, entry->dbe_id);
459
460 mutex_enter(table->dbt_lock);
461 table->dbt_count--;
462 mutex_exit(table->dbt_lock);
463
464 /* Destroy the entry itself */
465 kmem_cache_free(table->dbt_mem_cache, entry);
466 }
467
468
469 static rfs4_dbe_t *
rfs4_dbe_create(rfs4_table_t * table,id_t id,rfs4_entry_t data)470 rfs4_dbe_create(rfs4_table_t *table, id_t id, rfs4_entry_t data)
471 {
472 rfs4_dbe_t *entry;
473 int i;
474
475 NFS4_DEBUG(table->dbt_debug & CREATE_DEBUG,
476 (CE_NOTE, "Creating entry in table %s", table->dbt_name));
477
478 entry = kmem_cache_alloc(table->dbt_mem_cache, KM_SLEEP);
479
480 entry->dbe_refcnt = 1;
481 entry->dbe_invalid = FALSE;
482 entry->dbe_skipsearch = FALSE;
483 entry->dbe_time_rele = 0;
484 entry->dbe_id = 0;
485
486 if (table->dbt_id_space)
487 entry->dbe_id = id;
488 entry->dbe_table = table;
489
490 for (i = 0; i < table->dbt_maxcnt; i++) {
491 entry->dbe_indices[i].next = entry->dbe_indices[i].prev = NULL;
492 entry->dbe_indices[i].entry = entry;
493 /*
494 * We mark the entry as not indexed by setting the low
495 * order bit, since address are word aligned. This has
496 * the advantage of causeing a trap if the address is
497 * used. After the entry is linked in to the
498 * corresponding index the bit will be cleared.
499 */
500 INVALIDATE_ADDR(entry->dbe_indices[i].entry);
501 }
502
503 entry->dbe_data = (rfs4_entry_t)&entry->dbe_indices[table->dbt_maxcnt];
504 bzero(entry->dbe_data, table->dbt_usize);
505 entry->dbe_data->dbe = entry;
506
507 if (!(*table->dbt_create)(entry->dbe_data, data)) {
508 kmem_cache_free(table->dbt_mem_cache, entry);
509 return (NULL);
510 }
511
512 mutex_enter(table->dbt_lock);
513 table->dbt_count++;
514 mutex_exit(table->dbt_lock);
515
516 return (entry);
517 }
518
519 static void
rfs4_dbe_tabreap_adjust(rfs4_table_t * table)520 rfs4_dbe_tabreap_adjust(rfs4_table_t *table)
521 {
522 clock_t tabreap;
523 clock_t reap_int;
524 uint32_t in_use;
525
526 /*
527 * Adjust the table's reap interval based on the
528 * number of id's currently in use. Each table's
529 * default remains the same if id usage subsides.
530 */
531 ASSERT(MUTEX_HELD(&table->dbt_reaper_cv_lock));
532 tabreap = MIN(rfs4_reap_interval, table->dbt_max_cache_time);
533
534 in_use = table->dbt_count + 1; /* see rfs4_dbe_create */
535 if (in_use >= table->dbt_id_hwat) {
536 ASSERT(t_hreap != 0);
537 reap_int = (tabreap * t_hreap) / 100;
538 } else if (in_use >= table->dbt_id_lwat) {
539 ASSERT(t_lreap != 0);
540 reap_int = (tabreap * t_lreap) / 100;
541 } else {
542 reap_int = tabreap;
543 }
544 table->dbt_id_reap = reap_int;
545 DTRACE_PROBE2(table__reap__interval, char *,
546 table->dbt_name, time_t, table->dbt_id_reap);
547 }
548
549 rfs4_entry_t
rfs4_dbsearch(rfs4_index_t * idx,void * key,bool_t * create,void * arg,rfs4_dbsearch_type_t dbsearch_type)550 rfs4_dbsearch(rfs4_index_t *idx, void *key, bool_t *create, void *arg,
551 rfs4_dbsearch_type_t dbsearch_type)
552 {
553 int already_done;
554 uint32_t i;
555 rfs4_table_t *table = idx->dbi_table;
556 rfs4_index_t *ip;
557 rfs4_bucket_t *bp;
558 rfs4_link_t *l;
559 rfs4_dbe_t *entry;
560 id_t id = -1;
561
562 i = HASH(idx, key);
563 bp = &idx->dbi_buckets[i];
564
565 NFS4_DEBUG(table->dbt_debug & SEARCH_DEBUG,
566 (CE_NOTE, "Searching for key %p in table %s by %s",
567 key, table->dbt_name, idx->dbi_keyname));
568
569 rw_enter(bp->dbk_lock, RW_READER);
570 retry:
571 for (l = bp->dbk_head; l; l = l->next) {
572 if (l->entry->dbe_refcnt > 0 &&
573 (l->entry->dbe_skipsearch == FALSE ||
574 (l->entry->dbe_skipsearch == TRUE &&
575 dbsearch_type == RFS4_DBS_INVALID)) &&
576 (*idx->dbi_compare)(l->entry->dbe_data, key)) {
577 mutex_enter(l->entry->dbe_lock);
578 if (l->entry->dbe_refcnt == 0) {
579 mutex_exit(l->entry->dbe_lock);
580 continue;
581 }
582
583 /* place an additional hold since we are returning */
584 rfs4_dbe_hold(l->entry);
585
586 mutex_exit(l->entry->dbe_lock);
587 rw_exit(bp->dbk_lock);
588
589 *create = FALSE;
590
591 NFS4_DEBUG((table->dbt_debug & SEARCH_DEBUG),
592 (CE_NOTE, "Found entry %p for %p in table %s",
593 (void *)l->entry, key, table->dbt_name));
594
595 if (id != -1)
596 id_free(table->dbt_id_space, id);
597 return (l->entry->dbe_data);
598 }
599 }
600
601 if (!*create || table->dbt_create == NULL || !idx->dbi_createable ||
602 table->dbt_maxentries == table->dbt_count) {
603 NFS4_DEBUG(table->dbt_debug & SEARCH_DEBUG,
604 (CE_NOTE, "Entry for %p in %s not found",
605 key, table->dbt_name));
606
607 rw_exit(bp->dbk_lock);
608 if (id != -1)
609 id_free(table->dbt_id_space, id);
610 return (NULL);
611 }
612
613 if (table->dbt_id_space && id == -1) {
614 rw_exit(bp->dbk_lock);
615
616 /* get an id, ok to sleep for it here */
617 id = id_alloc(table->dbt_id_space);
618 ASSERT(id != -1);
619
620 mutex_enter(&table->dbt_reaper_cv_lock);
621 rfs4_dbe_tabreap_adjust(table);
622 mutex_exit(&table->dbt_reaper_cv_lock);
623
624 rw_enter(bp->dbk_lock, RW_WRITER);
625 goto retry;
626 }
627
628 /* get an exclusive lock on the bucket */
629 if (rw_read_locked(bp->dbk_lock) && !rw_tryupgrade(bp->dbk_lock)) {
630 NFS4_DEBUG(table->dbt_debug & OTHER_DEBUG,
631 (CE_NOTE, "Trying to upgrade lock on "
632 "hash chain %d (%p) for %s by %s",
633 i, (void*)bp, table->dbt_name, idx->dbi_keyname));
634
635 rw_exit(bp->dbk_lock);
636 rw_enter(bp->dbk_lock, RW_WRITER);
637 goto retry;
638 }
639
640 /* create entry */
641 entry = rfs4_dbe_create(table, id, arg);
642 if (entry == NULL) {
643 rw_exit(bp->dbk_lock);
644 if (id != -1)
645 id_free(table->dbt_id_space, id);
646
647 NFS4_DEBUG(table->dbt_debug & CREATE_DEBUG,
648 (CE_NOTE, "Constructor for table %s failed",
649 table->dbt_name));
650 return (NULL);
651 }
652
653 /*
654 * Add one ref for entry into table's hash - only one
655 * reference added even though there may be multiple indices
656 */
657 rfs4_dbe_hold(entry);
658 ENQUEUE(bp->dbk_head, &entry->dbe_indices[idx->dbi_tblidx]);
659 VALIDATE_ADDR(entry->dbe_indices[idx->dbi_tblidx].entry);
660
661 already_done = idx->dbi_tblidx;
662 rw_exit(bp->dbk_lock);
663
664 for (ip = table->dbt_indices; ip; ip = ip->dbi_inext) {
665 if (ip->dbi_tblidx == already_done)
666 continue;
667 l = &entry->dbe_indices[ip->dbi_tblidx];
668 i = HASH(ip, ip->dbi_mkkey(entry->dbe_data));
669 ASSERT(i < ip->dbi_table->dbt_len);
670 bp = &ip->dbi_buckets[i];
671 ENQUEUE_IDX(bp, l);
672 }
673
674 NFS4_DEBUG(
675 table->dbt_debug & SEARCH_DEBUG || table->dbt_debug & CREATE_DEBUG,
676 (CE_NOTE, "Entry %p created for %s = %p in table %s",
677 (void*)entry, idx->dbi_keyname, (void*)key, table->dbt_name));
678
679 return (entry->dbe_data);
680 }
681
682 /*ARGSUSED*/
683 boolean_t
rfs4_cpr_callb(void * arg,int code)684 rfs4_cpr_callb(void *arg, int code)
685 {
686 rfs4_table_t *table = rfs4_client_tab;
687 rfs4_bucket_t *buckets, *bp;
688 rfs4_link_t *l;
689 rfs4_client_t *cp;
690 int i;
691
692 /*
693 * We get called for Suspend and Resume events.
694 * For the suspend case we simply don't care! Nor do we care if
695 * there are no clients.
696 */
697 if (code == CB_CODE_CPR_CHKPT || table == NULL) {
698 return (B_TRUE);
699 }
700
701 buckets = table->dbt_indices->dbi_buckets;
702
703 /*
704 * When we get this far we are in the process of
705 * resuming the system from a previous suspend.
706 *
707 * We are going to blast through and update the
708 * last_access time for all the clients and in
709 * doing so extend them by one lease period.
710 */
711 for (i = 0; i < table->dbt_len; i++) {
712 bp = &buckets[i];
713 for (l = bp->dbk_head; l; l = l->next) {
714 cp = (rfs4_client_t *)l->entry->dbe_data;
715 cp->rc_last_access = gethrestime_sec();
716 }
717 }
718
719 return (B_TRUE);
720 }
721
722 /*
723 * Given a table, lock each of the buckets and walk all entries (in
724 * turn locking those) and calling the provided "callout" function
725 * with the provided parameter. Obviously used to iterate across all
726 * entries in a particular table via the database locking hierarchy.
727 * Obviously the caller must not hold locks on any of the entries in
728 * the specified table.
729 */
730 void
rfs4_dbe_walk(rfs4_table_t * table,void (* callout)(rfs4_entry_t,void *),void * data)731 rfs4_dbe_walk(rfs4_table_t *table,
732 void (*callout)(rfs4_entry_t, void *),
733 void *data)
734 {
735 rfs4_bucket_t *buckets = table->dbt_indices->dbi_buckets, *bp;
736 rfs4_link_t *l;
737 rfs4_dbe_t *entry;
738 int i;
739
740 NFS4_DEBUG(table->dbt_debug & WALK_DEBUG,
741 (CE_NOTE, "Walking entries in %s", table->dbt_name));
742
743 /* Walk the buckets looking for entries to release/destroy */
744 for (i = 0; i < table->dbt_len; i++) {
745 bp = &buckets[i];
746 rw_enter(bp->dbk_lock, RW_READER);
747 for (l = bp->dbk_head; l; l = l->next) {
748 entry = l->entry;
749 mutex_enter(entry->dbe_lock);
750 (*callout)(entry->dbe_data, data);
751 mutex_exit(entry->dbe_lock);
752 }
753 rw_exit(bp->dbk_lock);
754 }
755
756 NFS4_DEBUG(table->dbt_debug & WALK_DEBUG,
757 (CE_NOTE, "Walking entries complete %s", table->dbt_name));
758 }
759
760
761 static void
rfs4_dbe_reap(rfs4_table_t * table,time_t cache_time,uint32_t desired)762 rfs4_dbe_reap(rfs4_table_t *table, time_t cache_time, uint32_t desired)
763 {
764 rfs4_index_t *idx = table->dbt_indices;
765 rfs4_bucket_t *buckets = idx->dbi_buckets, *bp;
766 rfs4_link_t *l, *t;
767 rfs4_dbe_t *entry;
768 bool_t found;
769 int i;
770 int count = 0;
771
772 NFS4_DEBUG(table->dbt_debug & REAP_DEBUG,
773 (CE_NOTE, "Reaping %d entries older than %ld seconds in table %s",
774 desired, cache_time, table->dbt_name));
775
776 /* Walk the buckets looking for entries to release/destroy */
777 for (i = 0; i < table->dbt_len; i++) {
778 bp = &buckets[i];
779 do {
780 found = FALSE;
781 rw_enter(bp->dbk_lock, RW_READER);
782 for (l = bp->dbk_head; l; l = l->next) {
783 entry = l->entry;
784 /*
785 * Examine an entry. Ref count of 1 means
786 * that the only reference is for the hash
787 * table reference.
788 */
789 if (entry->dbe_refcnt != 1)
790 continue;
791 mutex_enter(entry->dbe_lock);
792 if ((entry->dbe_refcnt == 1) &&
793 (table->dbt_reaper_shutdown ||
794 table->dbt_expiry == NULL ||
795 (*table->dbt_expiry)(entry->dbe_data))) {
796 entry->dbe_refcnt--;
797 count++;
798 found = TRUE;
799 }
800 mutex_exit(entry->dbe_lock);
801 }
802 if (found) {
803 if (!rw_tryupgrade(bp->dbk_lock)) {
804 rw_exit(bp->dbk_lock);
805 rw_enter(bp->dbk_lock, RW_WRITER);
806 }
807
808 l = bp->dbk_head;
809 while (l) {
810 t = l;
811 entry = t->entry;
812 l = l->next;
813 if (entry->dbe_refcnt == 0) {
814 DEQUEUE(bp->dbk_head, t);
815 t->next = NULL;
816 t->prev = NULL;
817 INVALIDATE_ADDR(t->entry);
818 rfs4_dbe_destroy(entry);
819 }
820 }
821 }
822 rw_exit(bp->dbk_lock);
823 /*
824 * delay slightly if there is more work to do
825 * with the expectation that other reaper
826 * threads are freeing data structures as well
827 * and in turn will reduce ref counts on
828 * entries in this table allowing them to be
829 * released. This is only done in the
830 * instance that the tables are being shut down.
831 */
832 if (table->dbt_reaper_shutdown && bp->dbk_head != NULL)
833 delay(hz/100);
834 /*
835 * If this is a table shutdown, keep going until
836 * everything is gone
837 */
838 } while (table->dbt_reaper_shutdown && bp->dbk_head != NULL);
839
840 if (!table->dbt_reaper_shutdown && desired && count >= desired)
841 break;
842 }
843
844 NFS4_DEBUG(table->dbt_debug & REAP_DEBUG,
845 (CE_NOTE, "Reaped %d entries older than %ld seconds in table %s",
846 count, cache_time, table->dbt_name));
847 }
848
849 static void
reaper_thread(caddr_t * arg)850 reaper_thread(caddr_t *arg)
851 {
852 rfs4_table_t *table = (rfs4_table_t *)arg;
853 clock_t rc;
854
855 NFS4_DEBUG(table->dbt_debug,
856 (CE_NOTE, "rfs4_reaper_thread starting for %s", table->dbt_name));
857
858 CALLB_CPR_INIT(&table->dbt_reaper_cpr_info, &table->dbt_reaper_cv_lock,
859 callb_generic_cpr, "nfsv4Reaper");
860
861 mutex_enter(&table->dbt_reaper_cv_lock);
862 do {
863 CALLB_CPR_SAFE_BEGIN(&table->dbt_reaper_cpr_info);
864 rc = cv_reltimedwait_sig(&table->dbt_reaper_wait,
865 &table->dbt_reaper_cv_lock,
866 SEC_TO_TICK(table->dbt_id_reap), TR_CLOCK_TICK);
867 CALLB_CPR_SAFE_END(&table->dbt_reaper_cpr_info,
868 &table->dbt_reaper_cv_lock);
869 rfs4_dbe_reap(table, table->dbt_max_cache_time, 0);
870 } while (rc != 0 && table->dbt_reaper_shutdown == FALSE);
871
872 CALLB_CPR_EXIT(&table->dbt_reaper_cpr_info);
873
874 NFS4_DEBUG(table->dbt_debug,
875 (CE_NOTE, "rfs4_reaper_thread exiting for %s", table->dbt_name));
876
877 /* Notify the database shutdown processing that the table is shutdown */
878 mutex_enter(table->dbt_db->db_lock);
879 table->dbt_db->db_shutdown_count--;
880 cv_signal(&table->dbt_db->db_shutdown_wait);
881 mutex_exit(table->dbt_db->db_lock);
882 }
883
884 static void
rfs4_start_reaper(rfs4_table_t * table)885 rfs4_start_reaper(rfs4_table_t *table)
886 {
887 if (table->dbt_max_cache_time == 0)
888 return;
889
890 (void) thread_create(NULL, 0, reaper_thread, table, 0, &p0, TS_RUN,
891 minclsyspri);
892 }
893
894 #ifdef DEBUG
895 void
rfs4_dbe_debug(rfs4_dbe_t * entry)896 rfs4_dbe_debug(rfs4_dbe_t *entry)
897 {
898 cmn_err(CE_NOTE, "Entry %p from table %s",
899 (void *)entry, entry->dbe_table->dbt_name);
900 cmn_err(CE_CONT, "\trefcnt = %d id = %d",
901 entry->dbe_refcnt, entry->dbe_id);
902 }
903 #endif
904