blob: 2b06410e584e10d3f557b3b4bb58d0c660f56283 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * net/sunrpc/cache.c
3 *
4 * Generic code for various authentication-related caches
5 * used by sunrpc clients and servers.
6 *
7 * Copyright (C) 2002 Neil Brown <neilb@cse.unsw.edu.au>
8 *
9 * Released under terms in GPL version 2. See COPYING.
10 *
11 */
12
13#include <linux/types.h>
14#include <linux/fs.h>
15#include <linux/file.h>
16#include <linux/slab.h>
17#include <linux/signal.h>
18#include <linux/sched.h>
19#include <linux/kmod.h>
20#include <linux/list.h>
21#include <linux/module.h>
22#include <linux/ctype.h>
23#include <asm/uaccess.h>
24#include <linux/poll.h>
25#include <linux/seq_file.h>
26#include <linux/proc_fs.h>
27#include <linux/net.h>
28#include <linux/workqueue.h>
Arjan van de Ven4a3e2f72006-03-20 22:33:17 -080029#include <linux/mutex.h>
Trond Myklebustda770052009-08-09 15:14:28 -040030#include <linux/pagemap.h>
Frederic Weisbecker99df95a2010-04-13 22:46:36 +020031#include <linux/smp_lock.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070032#include <asm/ioctls.h>
33#include <linux/sunrpc/types.h>
34#include <linux/sunrpc/cache.h>
35#include <linux/sunrpc/stats.h>
Trond Myklebust8854e822009-08-09 15:14:30 -040036#include <linux/sunrpc/rpc_pipe_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070037
38#define RPCDBG_FACILITY RPCDBG_CACHE
39
J.Bruce Fieldse0bb89e2006-12-13 00:35:25 -080040static int cache_defer_req(struct cache_req *req, struct cache_head *item);
Linus Torvalds1da177e2005-04-16 15:20:36 -070041static void cache_revisit_request(struct cache_head *item);
42
Adrian Bunk74cae612006-03-27 01:15:10 -080043static void cache_init(struct cache_head *h)
Linus Torvalds1da177e2005-04-16 15:20:36 -070044{
45 time_t now = get_seconds();
46 h->next = NULL;
47 h->flags = 0;
NeilBrownbaab9352006-03-27 01:15:09 -080048 kref_init(&h->ref);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 h->expiry_time = now + CACHE_NEW_EXPIRY;
50 h->last_refresh = now;
51}
52
NeilBrown2f50d8b2010-02-03 17:31:31 +110053static inline int cache_is_expired(struct cache_detail *detail, struct cache_head *h)
54{
55 return (h->expiry_time < get_seconds()) ||
56 (detail->flush_time > h->last_refresh);
57}
58
NeilBrown15a5f6b2006-03-27 01:15:02 -080059struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail,
60 struct cache_head *key, int hash)
61{
62 struct cache_head **head, **hp;
NeilBrownd202cce2010-02-03 17:31:31 +110063 struct cache_head *new = NULL, *freeme = NULL;
NeilBrown15a5f6b2006-03-27 01:15:02 -080064
65 head = &detail->hash_table[hash];
66
67 read_lock(&detail->hash_lock);
68
69 for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
70 struct cache_head *tmp = *hp;
71 if (detail->match(tmp, key)) {
NeilBrownd202cce2010-02-03 17:31:31 +110072 if (cache_is_expired(detail, tmp))
73 /* This entry is expired, we will discard it. */
74 break;
NeilBrown15a5f6b2006-03-27 01:15:02 -080075 cache_get(tmp);
76 read_unlock(&detail->hash_lock);
77 return tmp;
78 }
79 }
80 read_unlock(&detail->hash_lock);
81 /* Didn't find anything, insert an empty entry */
82
83 new = detail->alloc();
84 if (!new)
85 return NULL;
Neil Brown2f349312006-08-05 12:14:29 -070086 /* must fully initialise 'new', else
87 * we might get lose if we need to
88 * cache_put it soon.
89 */
NeilBrown15a5f6b2006-03-27 01:15:02 -080090 cache_init(new);
Neil Brown2f349312006-08-05 12:14:29 -070091 detail->init(new, key);
NeilBrown15a5f6b2006-03-27 01:15:02 -080092
93 write_lock(&detail->hash_lock);
94
95 /* check if entry appeared while we slept */
96 for (hp=head; *hp != NULL ; hp = &(*hp)->next) {
97 struct cache_head *tmp = *hp;
98 if (detail->match(tmp, key)) {
NeilBrownd202cce2010-02-03 17:31:31 +110099 if (cache_is_expired(detail, tmp)) {
100 *hp = tmp->next;
101 tmp->next = NULL;
102 detail->entries --;
103 freeme = tmp;
104 break;
105 }
NeilBrown15a5f6b2006-03-27 01:15:02 -0800106 cache_get(tmp);
107 write_unlock(&detail->hash_lock);
NeilBrownbaab9352006-03-27 01:15:09 -0800108 cache_put(new, detail);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800109 return tmp;
110 }
111 }
NeilBrown15a5f6b2006-03-27 01:15:02 -0800112 new->next = *head;
113 *head = new;
114 detail->entries++;
115 cache_get(new);
116 write_unlock(&detail->hash_lock);
117
NeilBrownd202cce2010-02-03 17:31:31 +1100118 if (freeme)
119 cache_put(freeme, detail);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800120 return new;
121}
Trond Myklebust24c37672008-12-23 16:30:12 -0500122EXPORT_SYMBOL_GPL(sunrpc_cache_lookup);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800123
NeilBrownebd0cb12006-03-27 01:15:08 -0800124
NeilBrownf866a812009-08-04 15:22:38 +1000125static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch);
NeilBrownebd0cb12006-03-27 01:15:08 -0800126
NeilBrown908329f2009-09-09 16:32:54 +1000127static void cache_fresh_locked(struct cache_head *head, time_t expiry)
NeilBrownebd0cb12006-03-27 01:15:08 -0800128{
129 head->expiry_time = expiry;
130 head->last_refresh = get_seconds();
NeilBrown908329f2009-09-09 16:32:54 +1000131 set_bit(CACHE_VALID, &head->flags);
NeilBrownebd0cb12006-03-27 01:15:08 -0800132}
133
134static void cache_fresh_unlocked(struct cache_head *head,
NeilBrown908329f2009-09-09 16:32:54 +1000135 struct cache_detail *detail)
NeilBrownebd0cb12006-03-27 01:15:08 -0800136{
NeilBrownebd0cb12006-03-27 01:15:08 -0800137 if (test_and_clear_bit(CACHE_PENDING, &head->flags)) {
138 cache_revisit_request(head);
NeilBrownf866a812009-08-04 15:22:38 +1000139 cache_dequeue(detail, head);
NeilBrownebd0cb12006-03-27 01:15:08 -0800140 }
141}
142
NeilBrown15a5f6b2006-03-27 01:15:02 -0800143struct cache_head *sunrpc_cache_update(struct cache_detail *detail,
144 struct cache_head *new, struct cache_head *old, int hash)
145{
146 /* The 'old' entry is to be replaced by 'new'.
147 * If 'old' is not VALID, we update it directly,
148 * otherwise we need to replace it
149 */
150 struct cache_head **head;
151 struct cache_head *tmp;
152
153 if (!test_bit(CACHE_VALID, &old->flags)) {
154 write_lock(&detail->hash_lock);
155 if (!test_bit(CACHE_VALID, &old->flags)) {
156 if (test_bit(CACHE_NEGATIVE, &new->flags))
157 set_bit(CACHE_NEGATIVE, &old->flags);
158 else
159 detail->update(old, new);
NeilBrown908329f2009-09-09 16:32:54 +1000160 cache_fresh_locked(old, new->expiry_time);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800161 write_unlock(&detail->hash_lock);
NeilBrown908329f2009-09-09 16:32:54 +1000162 cache_fresh_unlocked(old, detail);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800163 return old;
164 }
165 write_unlock(&detail->hash_lock);
166 }
167 /* We need to insert a new entry */
168 tmp = detail->alloc();
169 if (!tmp) {
NeilBrownbaab9352006-03-27 01:15:09 -0800170 cache_put(old, detail);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800171 return NULL;
172 }
173 cache_init(tmp);
174 detail->init(tmp, old);
175 head = &detail->hash_table[hash];
176
177 write_lock(&detail->hash_lock);
178 if (test_bit(CACHE_NEGATIVE, &new->flags))
179 set_bit(CACHE_NEGATIVE, &tmp->flags);
180 else
181 detail->update(tmp, new);
182 tmp->next = *head;
183 *head = tmp;
NeilBrownf2d39582006-05-22 22:35:25 -0700184 detail->entries++;
NeilBrown15a5f6b2006-03-27 01:15:02 -0800185 cache_get(tmp);
NeilBrown908329f2009-09-09 16:32:54 +1000186 cache_fresh_locked(tmp, new->expiry_time);
NeilBrownebd0cb12006-03-27 01:15:08 -0800187 cache_fresh_locked(old, 0);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800188 write_unlock(&detail->hash_lock);
NeilBrown908329f2009-09-09 16:32:54 +1000189 cache_fresh_unlocked(tmp, detail);
190 cache_fresh_unlocked(old, detail);
NeilBrownbaab9352006-03-27 01:15:09 -0800191 cache_put(old, detail);
NeilBrown15a5f6b2006-03-27 01:15:02 -0800192 return tmp;
193}
Trond Myklebust24c37672008-12-23 16:30:12 -0500194EXPORT_SYMBOL_GPL(sunrpc_cache_update);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700195
Trond Myklebustbc74b4f2009-08-09 15:14:29 -0400196static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
197{
198 if (!cd->cache_upcall)
199 return -EINVAL;
200 return cd->cache_upcall(cd, h);
201}
NeilBrown989a19b2009-08-04 15:22:38 +1000202
203static inline int cache_is_valid(struct cache_detail *detail, struct cache_head *h)
204{
NeilBrownd202cce2010-02-03 17:31:31 +1100205 if (!test_bit(CACHE_VALID, &h->flags))
NeilBrown989a19b2009-08-04 15:22:38 +1000206 return -EAGAIN;
207 else {
208 /* entry is valid */
209 if (test_bit(CACHE_NEGATIVE, &h->flags))
210 return -ENOENT;
211 else
212 return 0;
213 }
214}
J. Bruce Fieldse9dc1222009-08-21 11:27:29 -0400215
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216/*
217 * This is the generic cache management routine for all
218 * the authentication caches.
219 * It checks the currency of a cache item and will (later)
220 * initiate an upcall to fill it if needed.
221 *
222 *
223 * Returns 0 if the cache_head can be used, or cache_puts it and returns
NeilBrown989a19b2009-08-04 15:22:38 +1000224 * -EAGAIN if upcall is pending and request has been queued
225 * -ETIMEDOUT if upcall failed or request could not be queue or
226 * upcall completed but item is still invalid (implying that
227 * the cache item has been replaced with a newer one).
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 * -ENOENT if cache entry was negative
229 */
230int cache_check(struct cache_detail *detail,
231 struct cache_head *h, struct cache_req *rqstp)
232{
233 int rv;
234 long refresh_age, age;
235
236 /* First decide return status as best we can */
NeilBrown989a19b2009-08-04 15:22:38 +1000237 rv = cache_is_valid(detail, h);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238
239 /* now see if we want to start an upcall */
240 refresh_age = (h->expiry_time - h->last_refresh);
241 age = get_seconds() - h->last_refresh;
242
243 if (rqstp == NULL) {
244 if (rv == -EAGAIN)
245 rv = -ENOENT;
246 } else if (rv == -EAGAIN || age > refresh_age/2) {
Chuck Lever46121cf2007-01-31 12:14:08 -0500247 dprintk("RPC: Want update, refage=%ld, age=%ld\n",
248 refresh_age, age);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 if (!test_and_set_bit(CACHE_PENDING, &h->flags)) {
250 switch (cache_make_upcall(detail, h)) {
251 case -EINVAL:
252 clear_bit(CACHE_PENDING, &h->flags);
NeilBrown5c4d2632009-08-04 15:22:38 +1000253 cache_revisit_request(h);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 if (rv == -EAGAIN) {
255 set_bit(CACHE_NEGATIVE, &h->flags);
NeilBrown908329f2009-09-09 16:32:54 +1000256 cache_fresh_locked(h, get_seconds()+CACHE_NEW_EXPIRY);
257 cache_fresh_unlocked(h, detail);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 rv = -ENOENT;
259 }
260 break;
261
262 case -EAGAIN:
263 clear_bit(CACHE_PENDING, &h->flags);
264 cache_revisit_request(h);
265 break;
266 }
267 }
268 }
269
NeilBrown989a19b2009-08-04 15:22:38 +1000270 if (rv == -EAGAIN) {
NeilBrown9e4c6372009-09-09 16:32:54 +1000271 if (cache_defer_req(rqstp, h) < 0) {
NeilBrown989a19b2009-08-04 15:22:38 +1000272 /* Request is not deferred */
273 rv = cache_is_valid(detail, h);
274 if (rv == -EAGAIN)
275 rv = -ETIMEDOUT;
276 }
277 }
NeilBrown4013ede2006-03-27 01:15:07 -0800278 if (rv)
NeilBrownbaab9352006-03-27 01:15:09 -0800279 cache_put(h, detail);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280 return rv;
281}
Trond Myklebust24c37672008-12-23 16:30:12 -0500282EXPORT_SYMBOL_GPL(cache_check);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700283
Linus Torvalds1da177e2005-04-16 15:20:36 -0700284/*
285 * caches need to be periodically cleaned.
286 * For this we maintain a list of cache_detail and
287 * a current pointer into that list and into the table
288 * for that entry.
289 *
290 * Each time clean_cache is called it finds the next non-empty entry
291 * in the current table and walks the list in that entry
292 * looking for entries that can be removed.
293 *
294 * An entry gets removed if:
295 * - The expiry is before current time
296 * - The last_refresh time is before the flush_time for that cache
297 *
298 * later we might drop old entries with non-NEVER expiry if that table
299 * is getting 'full' for some definition of 'full'
300 *
301 * The question of "how often to scan a table" is an interesting one
302 * and is answered in part by the use of the "nextcheck" field in the
303 * cache_detail.
304 * When a scan of a table begins, the nextcheck field is set to a time
305 * that is well into the future.
306 * While scanning, if an expiry time is found that is earlier than the
307 * current nextcheck time, nextcheck is set to that expiry time.
308 * If the flush_time is ever set to a time earlier than the nextcheck
309 * time, the nextcheck time is then set to that flush_time.
310 *
311 * A table is then only scanned if the current time is at least
312 * the nextcheck time.
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800313 *
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 */
315
316static LIST_HEAD(cache_list);
317static DEFINE_SPINLOCK(cache_list_lock);
318static struct cache_detail *current_detail;
319static int current_index;
320
David Howells65f27f32006-11-22 14:55:48 +0000321static void do_cache_clean(struct work_struct *work);
Artem Bityutskiy8eab9452010-07-01 18:05:56 +0300322static struct delayed_work cache_cleaner;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700323
Trond Myklebust5b7a1b92009-08-09 15:14:27 -0400324static void sunrpc_init_cache_detail(struct cache_detail *cd)
J. Bruce Fieldsffe93862007-11-12 17:04:29 -0500325{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326 rwlock_init(&cd->hash_lock);
327 INIT_LIST_HEAD(&cd->queue);
328 spin_lock(&cache_list_lock);
329 cd->nextcheck = 0;
330 cd->entries = 0;
331 atomic_set(&cd->readers, 0);
332 cd->last_close = 0;
333 cd->last_warn = -1;
334 list_add(&cd->others, &cache_list);
335 spin_unlock(&cache_list_lock);
336
337 /* start the cleaning process */
David Howells52bad642006-11-22 14:54:01 +0000338 schedule_delayed_work(&cache_cleaner, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339}
340
Trond Myklebust5b7a1b92009-08-09 15:14:27 -0400341static void sunrpc_destroy_cache_detail(struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342{
343 cache_purge(cd);
344 spin_lock(&cache_list_lock);
345 write_lock(&cd->hash_lock);
346 if (cd->entries || atomic_read(&cd->inuse)) {
347 write_unlock(&cd->hash_lock);
348 spin_unlock(&cache_list_lock);
J. Bruce Fieldsdf95a9d2007-11-08 16:09:59 -0500349 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 }
351 if (current_detail == cd)
352 current_detail = NULL;
353 list_del_init(&cd->others);
354 write_unlock(&cd->hash_lock);
355 spin_unlock(&cache_list_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 if (list_empty(&cache_list)) {
357 /* module must be being unloaded so its safe to kill the worker */
Trond Myklebust4011cd92007-08-07 15:33:01 -0400358 cancel_delayed_work_sync(&cache_cleaner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 }
J. Bruce Fieldsdf95a9d2007-11-08 16:09:59 -0500360 return;
361out:
362 printk(KERN_ERR "nfsd: failed to unregister %s cache\n", cd->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363}
364
365/* clean cache tries to find something to clean
366 * and cleans it.
367 * It returns 1 if it cleaned something,
368 * 0 if it didn't find anything this time
369 * -1 if it fell off the end of the list.
370 */
371static int cache_clean(void)
372{
373 int rv = 0;
374 struct list_head *next;
375
376 spin_lock(&cache_list_lock);
377
378 /* find a suitable table if we don't already have one */
379 while (current_detail == NULL ||
380 current_index >= current_detail->hash_size) {
381 if (current_detail)
382 next = current_detail->others.next;
383 else
384 next = cache_list.next;
385 if (next == &cache_list) {
386 current_detail = NULL;
387 spin_unlock(&cache_list_lock);
388 return -1;
389 }
390 current_detail = list_entry(next, struct cache_detail, others);
391 if (current_detail->nextcheck > get_seconds())
392 current_index = current_detail->hash_size;
393 else {
394 current_index = 0;
395 current_detail->nextcheck = get_seconds()+30*60;
396 }
397 }
398
399 /* find a non-empty bucket in the table */
400 while (current_detail &&
401 current_index < current_detail->hash_size &&
402 current_detail->hash_table[current_index] == NULL)
403 current_index++;
404
405 /* find a cleanable entry in the bucket and clean it, or set to next bucket */
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800406
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407 if (current_detail && current_index < current_detail->hash_size) {
408 struct cache_head *ch, **cp;
409 struct cache_detail *d;
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800410
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411 write_lock(&current_detail->hash_lock);
412
413 /* Ok, now to clean this strand */
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800414
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 cp = & current_detail->hash_table[current_index];
NeilBrown3af49742010-02-03 17:31:31 +1100416 for (ch = *cp ; ch ; cp = & ch->next, ch = *cp) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417 if (current_detail->nextcheck > ch->expiry_time)
418 current_detail->nextcheck = ch->expiry_time+1;
NeilBrown2f50d8b2010-02-03 17:31:31 +1100419 if (!cache_is_expired(current_detail, ch))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700420 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
Linus Torvalds1da177e2005-04-16 15:20:36 -0700422 *cp = ch->next;
423 ch->next = NULL;
424 current_detail->entries--;
425 rv = 1;
NeilBrown3af49742010-02-03 17:31:31 +1100426 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427 }
NeilBrown3af49742010-02-03 17:31:31 +1100428
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429 write_unlock(&current_detail->hash_lock);
430 d = current_detail;
431 if (!ch)
432 current_index ++;
433 spin_unlock(&cache_list_lock);
NeilBrown5c4d2632009-08-04 15:22:38 +1000434 if (ch) {
NeilBrown3af49742010-02-03 17:31:31 +1100435 if (test_and_clear_bit(CACHE_PENDING, &ch->flags))
436 cache_dequeue(current_detail, ch);
NeilBrown5c4d2632009-08-04 15:22:38 +1000437 cache_revisit_request(ch);
NeilBrownbaab9352006-03-27 01:15:09 -0800438 cache_put(ch, d);
NeilBrown5c4d2632009-08-04 15:22:38 +1000439 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700440 } else
441 spin_unlock(&cache_list_lock);
442
443 return rv;
444}
445
446/*
447 * We want to regularly clean the cache, so we need to schedule some work ...
448 */
David Howells65f27f32006-11-22 14:55:48 +0000449static void do_cache_clean(struct work_struct *work)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700450{
451 int delay = 5;
452 if (cache_clean() == -1)
Anton Blanchard6aad89c2009-06-10 12:52:21 -0700453 delay = round_jiffies_relative(30*HZ);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700454
455 if (list_empty(&cache_list))
456 delay = 0;
457
458 if (delay)
459 schedule_delayed_work(&cache_cleaner, delay);
460}
461
462
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800463/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464 * Clean all caches promptly. This just calls cache_clean
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800465 * repeatedly until we are sure that every cache has had a chance to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466 * be fully cleaned
467 */
468void cache_flush(void)
469{
470 while (cache_clean() != -1)
471 cond_resched();
472 while (cache_clean() != -1)
473 cond_resched();
474}
Trond Myklebust24c37672008-12-23 16:30:12 -0500475EXPORT_SYMBOL_GPL(cache_flush);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700476
477void cache_purge(struct cache_detail *detail)
478{
479 detail->flush_time = LONG_MAX;
480 detail->nextcheck = get_seconds();
481 cache_flush();
482 detail->flush_time = 1;
483}
Trond Myklebust24c37672008-12-23 16:30:12 -0500484EXPORT_SYMBOL_GPL(cache_purge);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485
486
487/*
488 * Deferral and Revisiting of Requests.
489 *
490 * If a cache lookup finds a pending entry, we
491 * need to defer the request and revisit it later.
492 * All deferred requests are stored in a hash table,
493 * indexed by "struct cache_head *".
494 * As it may be wasteful to store a whole request
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800495 * structure, we allow the request to provide a
Linus Torvalds1da177e2005-04-16 15:20:36 -0700496 * deferred form, which must contain a
497 * 'struct cache_deferred_req'
498 * This cache_deferred_req contains a method to allow
499 * it to be revisited when cache info is available
500 */
501
502#define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head))
503#define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE)
504
505#define DFR_MAX 300 /* ??? */
506
507static DEFINE_SPINLOCK(cache_defer_lock);
508static LIST_HEAD(cache_defer_list);
509static struct list_head cache_defer_hash[DFR_HASHSIZE];
510static int cache_defer_cnt;
511
J.Bruce Fieldse0bb89e2006-12-13 00:35:25 -0800512static int cache_defer_req(struct cache_req *req, struct cache_head *item)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513{
NeilBrowncd68c3742009-09-09 16:32:54 +1000514 struct cache_deferred_req *dreq, *discard;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700515 int hash = DFR_HASH(item);
516
J.Bruce Fields01f3bd12006-12-13 00:35:26 -0800517 if (cache_defer_cnt >= DFR_MAX) {
518 /* too much in the cache, randomly drop this one,
519 * or continue and drop the oldest below
520 */
521 if (net_random()&1)
NeilBrown9e4c6372009-09-09 16:32:54 +1000522 return -ENOMEM;
J.Bruce Fields01f3bd12006-12-13 00:35:26 -0800523 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 dreq = req->defer(req);
525 if (dreq == NULL)
NeilBrown9e4c6372009-09-09 16:32:54 +1000526 return -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527
528 dreq->item = item;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
530 spin_lock(&cache_defer_lock);
531
532 list_add(&dreq->recent, &cache_defer_list);
533
534 if (cache_defer_hash[hash].next == NULL)
535 INIT_LIST_HEAD(&cache_defer_hash[hash]);
536 list_add(&dreq->hash, &cache_defer_hash[hash]);
537
538 /* it is in, now maybe clean up */
NeilBrowncd68c3742009-09-09 16:32:54 +1000539 discard = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 if (++cache_defer_cnt > DFR_MAX) {
NeilBrowncd68c3742009-09-09 16:32:54 +1000541 discard = list_entry(cache_defer_list.prev,
542 struct cache_deferred_req, recent);
543 list_del_init(&discard->recent);
544 list_del_init(&discard->hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 cache_defer_cnt--;
546 }
547 spin_unlock(&cache_defer_lock);
548
NeilBrowncd68c3742009-09-09 16:32:54 +1000549 if (discard)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550 /* there was one too many */
NeilBrowncd68c3742009-09-09 16:32:54 +1000551 discard->revisit(discard, 1);
552
NeilBrown4013ede2006-03-27 01:15:07 -0800553 if (!test_bit(CACHE_PENDING, &item->flags)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700554 /* must have just been validated... */
555 cache_revisit_request(item);
NeilBrown9e4c6372009-09-09 16:32:54 +1000556 return -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 }
NeilBrown9e4c6372009-09-09 16:32:54 +1000558 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559}
560
561static void cache_revisit_request(struct cache_head *item)
562{
563 struct cache_deferred_req *dreq;
564 struct list_head pending;
565
566 struct list_head *lp;
567 int hash = DFR_HASH(item);
568
569 INIT_LIST_HEAD(&pending);
570 spin_lock(&cache_defer_lock);
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800571
Linus Torvalds1da177e2005-04-16 15:20:36 -0700572 lp = cache_defer_hash[hash].next;
573 if (lp) {
574 while (lp != &cache_defer_hash[hash]) {
575 dreq = list_entry(lp, struct cache_deferred_req, hash);
576 lp = lp->next;
577 if (dreq->item == item) {
NeilBrown67e73282009-09-09 16:32:54 +1000578 list_del_init(&dreq->hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 list_move(&dreq->recent, &pending);
580 cache_defer_cnt--;
581 }
582 }
583 }
584 spin_unlock(&cache_defer_lock);
585
586 while (!list_empty(&pending)) {
587 dreq = list_entry(pending.next, struct cache_deferred_req, recent);
588 list_del_init(&dreq->recent);
589 dreq->revisit(dreq, 0);
590 }
591}
592
593void cache_clean_deferred(void *owner)
594{
595 struct cache_deferred_req *dreq, *tmp;
596 struct list_head pending;
597
598
599 INIT_LIST_HEAD(&pending);
600 spin_lock(&cache_defer_lock);
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800601
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) {
603 if (dreq->owner == owner) {
NeilBrown67e73282009-09-09 16:32:54 +1000604 list_del_init(&dreq->hash);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 list_move(&dreq->recent, &pending);
606 cache_defer_cnt--;
607 }
608 }
609 spin_unlock(&cache_defer_lock);
610
611 while (!list_empty(&pending)) {
612 dreq = list_entry(pending.next, struct cache_deferred_req, recent);
613 list_del_init(&dreq->recent);
614 dreq->revisit(dreq, 1);
615 }
616}
617
618/*
619 * communicate with user-space
620 *
J. Bruce Fieldsa490c682007-11-06 14:15:19 -0500621 * We have a magic /proc file - /proc/sunrpc/<cachename>/channel.
622 * On read, you get a full request, or block.
623 * On write, an update request is processed.
624 * Poll works if anything to read, and always allows write.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 *
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800626 * Implemented by linked list of requests. Each open file has
J. Bruce Fieldsa490c682007-11-06 14:15:19 -0500627 * a ->private that also exists in this list. New requests are added
Linus Torvalds1da177e2005-04-16 15:20:36 -0700628 * to the end and may wakeup and preceding readers.
629 * New readers are added to the head. If, on read, an item is found with
630 * CACHE_UPCALLING clear, we free it from the list.
631 *
632 */
633
634static DEFINE_SPINLOCK(queue_lock);
Arjan van de Ven4a3e2f72006-03-20 22:33:17 -0800635static DEFINE_MUTEX(queue_io_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636
637struct cache_queue {
638 struct list_head list;
639 int reader; /* if 0, then request */
640};
641struct cache_request {
642 struct cache_queue q;
643 struct cache_head *item;
644 char * buf;
645 int len;
646 int readers;
647};
648struct cache_reader {
649 struct cache_queue q;
650 int offset; /* if non-0, we have a refcnt on next request */
651};
652
Trond Myklebust173912a2009-08-09 15:14:29 -0400653static ssize_t cache_read(struct file *filp, char __user *buf, size_t count,
654 loff_t *ppos, struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700655{
656 struct cache_reader *rp = filp->private_data;
657 struct cache_request *rq;
Trond Myklebustda770052009-08-09 15:14:28 -0400658 struct inode *inode = filp->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700659 int err;
660
661 if (count == 0)
662 return 0;
663
Trond Myklebustda770052009-08-09 15:14:28 -0400664 mutex_lock(&inode->i_mutex); /* protect against multiple concurrent
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 * readers on this file */
666 again:
667 spin_lock(&queue_lock);
668 /* need to find next request */
669 while (rp->q.list.next != &cd->queue &&
670 list_entry(rp->q.list.next, struct cache_queue, list)
671 ->reader) {
672 struct list_head *next = rp->q.list.next;
673 list_move(&rp->q.list, next);
674 }
675 if (rp->q.list.next == &cd->queue) {
676 spin_unlock(&queue_lock);
Trond Myklebustda770052009-08-09 15:14:28 -0400677 mutex_unlock(&inode->i_mutex);
Kris Katterjohn09a62662006-01-08 22:24:28 -0800678 BUG_ON(rp->offset);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700679 return 0;
680 }
681 rq = container_of(rp->q.list.next, struct cache_request, q.list);
Kris Katterjohn09a62662006-01-08 22:24:28 -0800682 BUG_ON(rq->q.reader);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700683 if (rp->offset == 0)
684 rq->readers++;
685 spin_unlock(&queue_lock);
686
687 if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) {
688 err = -EAGAIN;
689 spin_lock(&queue_lock);
690 list_move(&rp->q.list, &rq->q.list);
691 spin_unlock(&queue_lock);
692 } else {
693 if (rp->offset + count > rq->len)
694 count = rq->len - rp->offset;
695 err = -EFAULT;
696 if (copy_to_user(buf, rq->buf + rp->offset, count))
697 goto out;
698 rp->offset += count;
699 if (rp->offset >= rq->len) {
700 rp->offset = 0;
701 spin_lock(&queue_lock);
702 list_move(&rp->q.list, &rq->q.list);
703 spin_unlock(&queue_lock);
704 }
705 err = 0;
706 }
707 out:
708 if (rp->offset == 0) {
709 /* need to release rq */
710 spin_lock(&queue_lock);
711 rq->readers--;
712 if (rq->readers == 0 &&
713 !test_bit(CACHE_PENDING, &rq->item->flags)) {
714 list_del(&rq->q.list);
715 spin_unlock(&queue_lock);
NeilBrownbaab9352006-03-27 01:15:09 -0800716 cache_put(rq->item, cd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717 kfree(rq->buf);
718 kfree(rq);
719 } else
720 spin_unlock(&queue_lock);
721 }
722 if (err == -EAGAIN)
723 goto again;
Trond Myklebustda770052009-08-09 15:14:28 -0400724 mutex_unlock(&inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700725 return err ? err : count;
726}
727
Trond Myklebustda770052009-08-09 15:14:28 -0400728static ssize_t cache_do_downcall(char *kaddr, const char __user *buf,
729 size_t count, struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730{
Trond Myklebustda770052009-08-09 15:14:28 -0400731 ssize_t ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732
Trond Myklebustda770052009-08-09 15:14:28 -0400733 if (copy_from_user(kaddr, buf, count))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700734 return -EFAULT;
Trond Myklebustda770052009-08-09 15:14:28 -0400735 kaddr[count] = '\0';
736 ret = cd->cache_parse(cd, kaddr, count);
737 if (!ret)
738 ret = count;
739 return ret;
740}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741
Trond Myklebustda770052009-08-09 15:14:28 -0400742static ssize_t cache_slow_downcall(const char __user *buf,
743 size_t count, struct cache_detail *cd)
744{
745 static char write_buf[8192]; /* protected by queue_io_mutex */
746 ssize_t ret = -EINVAL;
747
748 if (count >= sizeof(write_buf))
749 goto out;
750 mutex_lock(&queue_io_mutex);
751 ret = cache_do_downcall(write_buf, buf, count, cd);
Arjan van de Ven4a3e2f72006-03-20 22:33:17 -0800752 mutex_unlock(&queue_io_mutex);
Trond Myklebustda770052009-08-09 15:14:28 -0400753out:
754 return ret;
755}
756
757static ssize_t cache_downcall(struct address_space *mapping,
758 const char __user *buf,
759 size_t count, struct cache_detail *cd)
760{
761 struct page *page;
762 char *kaddr;
763 ssize_t ret = -ENOMEM;
764
765 if (count >= PAGE_CACHE_SIZE)
766 goto out_slow;
767
768 page = find_or_create_page(mapping, 0, GFP_KERNEL);
769 if (!page)
770 goto out_slow;
771
772 kaddr = kmap(page);
773 ret = cache_do_downcall(kaddr, buf, count, cd);
774 kunmap(page);
775 unlock_page(page);
776 page_cache_release(page);
777 return ret;
778out_slow:
779 return cache_slow_downcall(buf, count, cd);
780}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781
Trond Myklebust173912a2009-08-09 15:14:29 -0400782static ssize_t cache_write(struct file *filp, const char __user *buf,
783 size_t count, loff_t *ppos,
784 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785{
Trond Myklebustda770052009-08-09 15:14:28 -0400786 struct address_space *mapping = filp->f_mapping;
787 struct inode *inode = filp->f_path.dentry->d_inode;
Trond Myklebustda770052009-08-09 15:14:28 -0400788 ssize_t ret = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
Trond Myklebustda770052009-08-09 15:14:28 -0400790 if (!cd->cache_parse)
791 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792
Trond Myklebustda770052009-08-09 15:14:28 -0400793 mutex_lock(&inode->i_mutex);
794 ret = cache_downcall(mapping, buf, count, cd);
795 mutex_unlock(&inode->i_mutex);
796out:
797 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798}
799
800static DECLARE_WAIT_QUEUE_HEAD(queue_wait);
801
Trond Myklebust173912a2009-08-09 15:14:29 -0400802static unsigned int cache_poll(struct file *filp, poll_table *wait,
803 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804{
805 unsigned int mask;
806 struct cache_reader *rp = filp->private_data;
807 struct cache_queue *cq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808
809 poll_wait(filp, &queue_wait, wait);
810
811 /* alway allow write */
812 mask = POLL_OUT | POLLWRNORM;
813
814 if (!rp)
815 return mask;
816
817 spin_lock(&queue_lock);
818
819 for (cq= &rp->q; &cq->list != &cd->queue;
820 cq = list_entry(cq->list.next, struct cache_queue, list))
821 if (!cq->reader) {
822 mask |= POLLIN | POLLRDNORM;
823 break;
824 }
825 spin_unlock(&queue_lock);
826 return mask;
827}
828
Trond Myklebust173912a2009-08-09 15:14:29 -0400829static int cache_ioctl(struct inode *ino, struct file *filp,
830 unsigned int cmd, unsigned long arg,
831 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700832{
833 int len = 0;
834 struct cache_reader *rp = filp->private_data;
835 struct cache_queue *cq;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836
837 if (cmd != FIONREAD || !rp)
838 return -EINVAL;
839
840 spin_lock(&queue_lock);
841
842 /* only find the length remaining in current request,
843 * or the length of the next request
844 */
845 for (cq= &rp->q; &cq->list != &cd->queue;
846 cq = list_entry(cq->list.next, struct cache_queue, list))
847 if (!cq->reader) {
848 struct cache_request *cr =
849 container_of(cq, struct cache_request, q);
850 len = cr->len - rp->offset;
851 break;
852 }
853 spin_unlock(&queue_lock);
854
855 return put_user(len, (int __user *)arg);
856}
857
Trond Myklebust173912a2009-08-09 15:14:29 -0400858static int cache_open(struct inode *inode, struct file *filp,
859 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860{
861 struct cache_reader *rp = NULL;
862
Trond Myklebustf7e86ab2009-08-19 18:13:00 -0400863 if (!cd || !try_module_get(cd->owner))
864 return -EACCES;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700865 nonseekable_open(inode, filp);
866 if (filp->f_mode & FMODE_READ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 rp = kmalloc(sizeof(*rp), GFP_KERNEL);
868 if (!rp)
869 return -ENOMEM;
870 rp->offset = 0;
871 rp->q.reader = 1;
872 atomic_inc(&cd->readers);
873 spin_lock(&queue_lock);
874 list_add(&rp->q.list, &cd->queue);
875 spin_unlock(&queue_lock);
876 }
877 filp->private_data = rp;
878 return 0;
879}
880
Trond Myklebust173912a2009-08-09 15:14:29 -0400881static int cache_release(struct inode *inode, struct file *filp,
882 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700883{
884 struct cache_reader *rp = filp->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885
886 if (rp) {
887 spin_lock(&queue_lock);
888 if (rp->offset) {
889 struct cache_queue *cq;
890 for (cq= &rp->q; &cq->list != &cd->queue;
891 cq = list_entry(cq->list.next, struct cache_queue, list))
892 if (!cq->reader) {
893 container_of(cq, struct cache_request, q)
894 ->readers--;
895 break;
896 }
897 rp->offset = 0;
898 }
899 list_del(&rp->q.list);
900 spin_unlock(&queue_lock);
901
902 filp->private_data = NULL;
903 kfree(rp);
904
905 cd->last_close = get_seconds();
906 atomic_dec(&cd->readers);
907 }
Trond Myklebustf7e86ab2009-08-19 18:13:00 -0400908 module_put(cd->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 return 0;
910}
911
912
913
NeilBrownf866a812009-08-04 15:22:38 +1000914static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915{
916 struct cache_queue *cq;
917 spin_lock(&queue_lock);
918 list_for_each_entry(cq, &detail->queue, list)
919 if (!cq->reader) {
920 struct cache_request *cr = container_of(cq, struct cache_request, q);
921 if (cr->item != ch)
922 continue;
923 if (cr->readers != 0)
NeilBrown4013ede2006-03-27 01:15:07 -0800924 continue;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700925 list_del(&cr->q.list);
926 spin_unlock(&queue_lock);
NeilBrownbaab9352006-03-27 01:15:09 -0800927 cache_put(cr->item, detail);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928 kfree(cr->buf);
929 kfree(cr);
930 return;
931 }
932 spin_unlock(&queue_lock);
933}
934
935/*
936 * Support routines for text-based upcalls.
937 * Fields are separated by spaces.
938 * Fields are either mangled to quote space tab newline slosh with slosh
939 * or a hexified with a leading \x
940 * Record is terminated with newline.
941 *
942 */
943
944void qword_add(char **bpp, int *lp, char *str)
945{
946 char *bp = *bpp;
947 int len = *lp;
948 char c;
949
950 if (len < 0) return;
951
952 while ((c=*str++) && len)
953 switch(c) {
954 case ' ':
955 case '\t':
956 case '\n':
957 case '\\':
958 if (len >= 4) {
959 *bp++ = '\\';
960 *bp++ = '0' + ((c & 0300)>>6);
961 *bp++ = '0' + ((c & 0070)>>3);
962 *bp++ = '0' + ((c & 0007)>>0);
963 }
964 len -= 4;
965 break;
966 default:
967 *bp++ = c;
968 len--;
969 }
970 if (c || len <1) len = -1;
971 else {
972 *bp++ = ' ';
973 len--;
974 }
975 *bpp = bp;
976 *lp = len;
977}
Trond Myklebust24c37672008-12-23 16:30:12 -0500978EXPORT_SYMBOL_GPL(qword_add);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700979
980void qword_addhex(char **bpp, int *lp, char *buf, int blen)
981{
982 char *bp = *bpp;
983 int len = *lp;
984
985 if (len < 0) return;
986
987 if (len > 2) {
988 *bp++ = '\\';
989 *bp++ = 'x';
990 len -= 2;
991 while (blen && len >= 2) {
992 unsigned char c = *buf++;
993 *bp++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1);
994 *bp++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1);
995 len -= 2;
996 blen--;
997 }
998 }
999 if (blen || len<1) len = -1;
1000 else {
1001 *bp++ = ' ';
1002 len--;
1003 }
1004 *bpp = bp;
1005 *lp = len;
1006}
Trond Myklebust24c37672008-12-23 16:30:12 -05001007EXPORT_SYMBOL_GPL(qword_addhex);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008
1009static void warn_no_listener(struct cache_detail *detail)
1010{
1011 if (detail->last_warn != detail->last_close) {
1012 detail->last_warn = detail->last_close;
1013 if (detail->warn_no_listener)
Trond Myklebust2da8ca22009-08-09 15:14:26 -04001014 detail->warn_no_listener(detail, detail->last_close != 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001015 }
1016}
1017
1018/*
Trond Myklebustbc74b4f2009-08-09 15:14:29 -04001019 * register an upcall request to user-space and queue it up for read() by the
1020 * upcall daemon.
1021 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07001022 * Each request is at most one page long.
1023 */
Trond Myklebustbc74b4f2009-08-09 15:14:29 -04001024int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
1025 void (*cache_request)(struct cache_detail *,
1026 struct cache_head *,
1027 char **,
1028 int *))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001029{
1030
1031 char *buf;
1032 struct cache_request *crq;
1033 char *bp;
1034 int len;
1035
Linus Torvalds1da177e2005-04-16 15:20:36 -07001036 if (atomic_read(&detail->readers) == 0 &&
1037 detail->last_close < get_seconds() - 30) {
1038 warn_no_listener(detail);
1039 return -EINVAL;
1040 }
1041
1042 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
1043 if (!buf)
1044 return -EAGAIN;
1045
1046 crq = kmalloc(sizeof (*crq), GFP_KERNEL);
1047 if (!crq) {
1048 kfree(buf);
1049 return -EAGAIN;
1050 }
1051
1052 bp = buf; len = PAGE_SIZE;
1053
Trond Myklebustbc74b4f2009-08-09 15:14:29 -04001054 cache_request(detail, h, &bp, &len);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001055
1056 if (len < 0) {
1057 kfree(buf);
1058 kfree(crq);
1059 return -EAGAIN;
1060 }
1061 crq->q.reader = 0;
1062 crq->item = cache_get(h);
1063 crq->buf = buf;
1064 crq->len = PAGE_SIZE - len;
1065 crq->readers = 0;
1066 spin_lock(&queue_lock);
1067 list_add_tail(&crq->q.list, &detail->queue);
1068 spin_unlock(&queue_lock);
1069 wake_up(&queue_wait);
1070 return 0;
1071}
Trond Myklebustbc74b4f2009-08-09 15:14:29 -04001072EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001073
1074/*
1075 * parse a message from user-space and pass it
1076 * to an appropriate cache
1077 * Messages are, like requests, separated into fields by
1078 * spaces and dequotes as \xHEXSTRING or embedded \nnn octal
1079 *
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -08001080 * Message is
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 * reply cachename expiry key ... content....
1082 *
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -08001083 * key and content are both parsed by cache
Linus Torvalds1da177e2005-04-16 15:20:36 -07001084 */
1085
1086#define isodigit(c) (isdigit(c) && c <= '7')
1087int qword_get(char **bpp, char *dest, int bufsize)
1088{
1089 /* return bytes copied, or -1 on error */
1090 char *bp = *bpp;
1091 int len = 0;
1092
1093 while (*bp == ' ') bp++;
1094
1095 if (bp[0] == '\\' && bp[1] == 'x') {
1096 /* HEX STRING */
1097 bp += 2;
1098 while (isxdigit(bp[0]) && isxdigit(bp[1]) && len < bufsize) {
1099 int byte = isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1100 bp++;
1101 byte <<= 4;
1102 byte |= isdigit(*bp) ? *bp-'0' : toupper(*bp)-'A'+10;
1103 *dest++ = byte;
1104 bp++;
1105 len++;
1106 }
1107 } else {
1108 /* text with \nnn octal quoting */
1109 while (*bp != ' ' && *bp != '\n' && *bp && len < bufsize-1) {
1110 if (*bp == '\\' &&
1111 isodigit(bp[1]) && (bp[1] <= '3') &&
1112 isodigit(bp[2]) &&
1113 isodigit(bp[3])) {
1114 int byte = (*++bp -'0');
1115 bp++;
1116 byte = (byte << 3) | (*bp++ - '0');
1117 byte = (byte << 3) | (*bp++ - '0');
1118 *dest++ = byte;
1119 len++;
1120 } else {
1121 *dest++ = *bp++;
1122 len++;
1123 }
1124 }
1125 }
1126
1127 if (*bp != ' ' && *bp != '\n' && *bp != '\0')
1128 return -1;
1129 while (*bp == ' ') bp++;
1130 *bpp = bp;
1131 *dest = '\0';
1132 return len;
1133}
Trond Myklebust24c37672008-12-23 16:30:12 -05001134EXPORT_SYMBOL_GPL(qword_get);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001135
1136
1137/*
1138 * support /proc/sunrpc/cache/$CACHENAME/content
1139 * as a seqfile.
1140 * We call ->cache_show passing NULL for the item to
1141 * get a header, then pass each real item in the cache
1142 */
1143
1144struct handle {
1145 struct cache_detail *cd;
1146};
1147
1148static void *c_start(struct seq_file *m, loff_t *pos)
Eric Dumazet9a429c42008-01-01 21:58:02 -08001149 __acquires(cd->hash_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150{
1151 loff_t n = *pos;
1152 unsigned hash, entry;
1153 struct cache_head *ch;
1154 struct cache_detail *cd = ((struct handle*)m->private)->cd;
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -08001155
Linus Torvalds1da177e2005-04-16 15:20:36 -07001156
1157 read_lock(&cd->hash_lock);
1158 if (!n--)
1159 return SEQ_START_TOKEN;
1160 hash = n >> 32;
1161 entry = n & ((1LL<<32) - 1);
1162
1163 for (ch=cd->hash_table[hash]; ch; ch=ch->next)
1164 if (!entry--)
1165 return ch;
1166 n &= ~((1LL<<32) - 1);
1167 do {
1168 hash++;
1169 n += 1LL<<32;
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -08001170 } while(hash < cd->hash_size &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07001171 cd->hash_table[hash]==NULL);
1172 if (hash >= cd->hash_size)
1173 return NULL;
1174 *pos = n+1;
1175 return cd->hash_table[hash];
1176}
1177
1178static void *c_next(struct seq_file *m, void *p, loff_t *pos)
1179{
1180 struct cache_head *ch = p;
1181 int hash = (*pos >> 32);
1182 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1183
1184 if (p == SEQ_START_TOKEN)
1185 hash = 0;
1186 else if (ch->next == NULL) {
1187 hash++;
1188 *pos += 1LL<<32;
1189 } else {
1190 ++*pos;
1191 return ch->next;
1192 }
1193 *pos &= ~((1LL<<32) - 1);
1194 while (hash < cd->hash_size &&
1195 cd->hash_table[hash] == NULL) {
1196 hash++;
1197 *pos += 1LL<<32;
1198 }
1199 if (hash >= cd->hash_size)
1200 return NULL;
1201 ++*pos;
1202 return cd->hash_table[hash];
1203}
1204
1205static void c_stop(struct seq_file *m, void *p)
Eric Dumazet9a429c42008-01-01 21:58:02 -08001206 __releases(cd->hash_lock)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001207{
1208 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1209 read_unlock(&cd->hash_lock);
1210}
1211
1212static int c_show(struct seq_file *m, void *p)
1213{
1214 struct cache_head *cp = p;
1215 struct cache_detail *cd = ((struct handle*)m->private)->cd;
1216
1217 if (p == SEQ_START_TOKEN)
1218 return cd->cache_show(m, cd, NULL);
1219
1220 ifdebug(CACHE)
NeilBrown4013ede2006-03-27 01:15:07 -08001221 seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n",
NeilBrownbaab9352006-03-27 01:15:09 -08001222 cp->expiry_time, atomic_read(&cp->ref.refcount), cp->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223 cache_get(cp);
1224 if (cache_check(cd, cp, NULL))
1225 /* cache_check does a cache_put on failure */
1226 seq_printf(m, "# ");
1227 else
1228 cache_put(cp, cd);
1229
1230 return cd->cache_show(m, cd, cp);
1231}
1232
Philippe De Muyter56b3d972007-07-10 23:07:31 -07001233static const struct seq_operations cache_content_op = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001234 .start = c_start,
1235 .next = c_next,
1236 .stop = c_stop,
1237 .show = c_show,
1238};
1239
Trond Myklebust173912a2009-08-09 15:14:29 -04001240static int content_open(struct inode *inode, struct file *file,
1241 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001242{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243 struct handle *han;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001244
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001245 if (!cd || !try_module_get(cd->owner))
1246 return -EACCES;
Pavel Emelyanovec931032007-10-10 02:31:07 -07001247 han = __seq_open_private(file, &cache_content_op, sizeof(*han));
Li Zefana5990ea2010-03-11 14:08:10 -08001248 if (han == NULL) {
1249 module_put(cd->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001250 return -ENOMEM;
Li Zefana5990ea2010-03-11 14:08:10 -08001251 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001252
1253 han->cd = cd;
Pavel Emelyanovec931032007-10-10 02:31:07 -07001254 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001255}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001256
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001257static int content_release(struct inode *inode, struct file *file,
1258 struct cache_detail *cd)
1259{
1260 int ret = seq_release_private(inode, file);
1261 module_put(cd->owner);
1262 return ret;
1263}
1264
1265static int open_flush(struct inode *inode, struct file *file,
1266 struct cache_detail *cd)
1267{
1268 if (!cd || !try_module_get(cd->owner))
1269 return -EACCES;
1270 return nonseekable_open(inode, file);
1271}
1272
1273static int release_flush(struct inode *inode, struct file *file,
1274 struct cache_detail *cd)
1275{
1276 module_put(cd->owner);
1277 return 0;
1278}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001279
1280static ssize_t read_flush(struct file *file, char __user *buf,
Trond Myklebust173912a2009-08-09 15:14:29 -04001281 size_t count, loff_t *ppos,
1282 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001284 char tbuf[20];
1285 unsigned long p = *ppos;
Chuck Lever01b29692007-10-26 13:31:20 -04001286 size_t len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001287
1288 sprintf(tbuf, "%lu\n", cd->flush_time);
1289 len = strlen(tbuf);
1290 if (p >= len)
1291 return 0;
1292 len -= p;
Chuck Lever01b29692007-10-26 13:31:20 -04001293 if (len > count)
1294 len = count;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 if (copy_to_user(buf, (void*)(tbuf+p), len))
Chuck Lever01b29692007-10-26 13:31:20 -04001296 return -EFAULT;
1297 *ppos += len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001298 return len;
1299}
1300
Trond Myklebust173912a2009-08-09 15:14:29 -04001301static ssize_t write_flush(struct file *file, const char __user *buf,
1302 size_t count, loff_t *ppos,
1303 struct cache_detail *cd)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304{
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305 char tbuf[20];
1306 char *ep;
1307 long flushtime;
1308 if (*ppos || count > sizeof(tbuf)-1)
1309 return -EINVAL;
1310 if (copy_from_user(tbuf, buf, count))
1311 return -EFAULT;
1312 tbuf[count] = 0;
1313 flushtime = simple_strtoul(tbuf, &ep, 0);
1314 if (*ep && *ep != '\n')
1315 return -EINVAL;
1316
1317 cd->flush_time = flushtime;
1318 cd->nextcheck = get_seconds();
1319 cache_flush();
1320
1321 *ppos += count;
1322 return count;
1323}
1324
Trond Myklebust173912a2009-08-09 15:14:29 -04001325static ssize_t cache_read_procfs(struct file *filp, char __user *buf,
1326 size_t count, loff_t *ppos)
1327{
1328 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1329
1330 return cache_read(filp, buf, count, ppos, cd);
1331}
1332
1333static ssize_t cache_write_procfs(struct file *filp, const char __user *buf,
1334 size_t count, loff_t *ppos)
1335{
1336 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1337
1338 return cache_write(filp, buf, count, ppos, cd);
1339}
1340
1341static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait)
1342{
1343 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1344
1345 return cache_poll(filp, wait, cd);
1346}
1347
Frederic Weisbeckerd79b6f42010-03-30 07:27:50 +02001348static long cache_ioctl_procfs(struct file *filp,
1349 unsigned int cmd, unsigned long arg)
Trond Myklebust173912a2009-08-09 15:14:29 -04001350{
Frederic Weisbeckerd79b6f42010-03-30 07:27:50 +02001351 long ret;
1352 struct inode *inode = filp->f_path.dentry->d_inode;
Trond Myklebust173912a2009-08-09 15:14:29 -04001353 struct cache_detail *cd = PDE(inode)->data;
1354
Frederic Weisbeckerd79b6f42010-03-30 07:27:50 +02001355 lock_kernel();
1356 ret = cache_ioctl(inode, filp, cmd, arg, cd);
1357 unlock_kernel();
1358
1359 return ret;
Trond Myklebust173912a2009-08-09 15:14:29 -04001360}
1361
1362static int cache_open_procfs(struct inode *inode, struct file *filp)
1363{
1364 struct cache_detail *cd = PDE(inode)->data;
1365
1366 return cache_open(inode, filp, cd);
1367}
1368
1369static int cache_release_procfs(struct inode *inode, struct file *filp)
1370{
1371 struct cache_detail *cd = PDE(inode)->data;
1372
1373 return cache_release(inode, filp, cd);
1374}
1375
1376static const struct file_operations cache_file_operations_procfs = {
1377 .owner = THIS_MODULE,
1378 .llseek = no_llseek,
1379 .read = cache_read_procfs,
1380 .write = cache_write_procfs,
1381 .poll = cache_poll_procfs,
Frederic Weisbeckerd79b6f42010-03-30 07:27:50 +02001382 .unlocked_ioctl = cache_ioctl_procfs, /* for FIONREAD */
Trond Myklebust173912a2009-08-09 15:14:29 -04001383 .open = cache_open_procfs,
1384 .release = cache_release_procfs,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001385};
Trond Myklebust173912a2009-08-09 15:14:29 -04001386
1387static int content_open_procfs(struct inode *inode, struct file *filp)
1388{
1389 struct cache_detail *cd = PDE(inode)->data;
1390
1391 return content_open(inode, filp, cd);
1392}
1393
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001394static int content_release_procfs(struct inode *inode, struct file *filp)
1395{
1396 struct cache_detail *cd = PDE(inode)->data;
1397
1398 return content_release(inode, filp, cd);
1399}
1400
Trond Myklebust173912a2009-08-09 15:14:29 -04001401static const struct file_operations content_file_operations_procfs = {
1402 .open = content_open_procfs,
1403 .read = seq_read,
1404 .llseek = seq_lseek,
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001405 .release = content_release_procfs,
Trond Myklebust173912a2009-08-09 15:14:29 -04001406};
1407
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001408static int open_flush_procfs(struct inode *inode, struct file *filp)
1409{
1410 struct cache_detail *cd = PDE(inode)->data;
1411
1412 return open_flush(inode, filp, cd);
1413}
1414
1415static int release_flush_procfs(struct inode *inode, struct file *filp)
1416{
1417 struct cache_detail *cd = PDE(inode)->data;
1418
1419 return release_flush(inode, filp, cd);
1420}
1421
Trond Myklebust173912a2009-08-09 15:14:29 -04001422static ssize_t read_flush_procfs(struct file *filp, char __user *buf,
1423 size_t count, loff_t *ppos)
1424{
1425 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1426
1427 return read_flush(filp, buf, count, ppos, cd);
1428}
1429
1430static ssize_t write_flush_procfs(struct file *filp,
1431 const char __user *buf,
1432 size_t count, loff_t *ppos)
1433{
1434 struct cache_detail *cd = PDE(filp->f_path.dentry->d_inode)->data;
1435
1436 return write_flush(filp, buf, count, ppos, cd);
1437}
1438
1439static const struct file_operations cache_flush_operations_procfs = {
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001440 .open = open_flush_procfs,
Trond Myklebust173912a2009-08-09 15:14:29 -04001441 .read = read_flush_procfs,
1442 .write = write_flush_procfs,
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001443 .release = release_flush_procfs,
Trond Myklebust173912a2009-08-09 15:14:29 -04001444};
1445
1446static void remove_cache_proc_entries(struct cache_detail *cd)
1447{
1448 if (cd->u.procfs.proc_ent == NULL)
1449 return;
1450 if (cd->u.procfs.flush_ent)
1451 remove_proc_entry("flush", cd->u.procfs.proc_ent);
1452 if (cd->u.procfs.channel_ent)
1453 remove_proc_entry("channel", cd->u.procfs.proc_ent);
1454 if (cd->u.procfs.content_ent)
1455 remove_proc_entry("content", cd->u.procfs.proc_ent);
1456 cd->u.procfs.proc_ent = NULL;
1457 remove_proc_entry(cd->name, proc_net_rpc);
1458}
1459
1460#ifdef CONFIG_PROC_FS
1461static int create_cache_proc_entries(struct cache_detail *cd)
1462{
1463 struct proc_dir_entry *p;
1464
1465 cd->u.procfs.proc_ent = proc_mkdir(cd->name, proc_net_rpc);
1466 if (cd->u.procfs.proc_ent == NULL)
1467 goto out_nomem;
1468 cd->u.procfs.channel_ent = NULL;
1469 cd->u.procfs.content_ent = NULL;
1470
1471 p = proc_create_data("flush", S_IFREG|S_IRUSR|S_IWUSR,
1472 cd->u.procfs.proc_ent,
1473 &cache_flush_operations_procfs, cd);
1474 cd->u.procfs.flush_ent = p;
1475 if (p == NULL)
1476 goto out_nomem;
1477
1478 if (cd->cache_upcall || cd->cache_parse) {
1479 p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR,
1480 cd->u.procfs.proc_ent,
1481 &cache_file_operations_procfs, cd);
1482 cd->u.procfs.channel_ent = p;
1483 if (p == NULL)
1484 goto out_nomem;
1485 }
1486 if (cd->cache_show) {
1487 p = proc_create_data("content", S_IFREG|S_IRUSR|S_IWUSR,
1488 cd->u.procfs.proc_ent,
1489 &content_file_operations_procfs, cd);
1490 cd->u.procfs.content_ent = p;
1491 if (p == NULL)
1492 goto out_nomem;
1493 }
1494 return 0;
1495out_nomem:
1496 remove_cache_proc_entries(cd);
1497 return -ENOMEM;
1498}
1499#else /* CONFIG_PROC_FS */
1500static int create_cache_proc_entries(struct cache_detail *cd)
1501{
1502 return 0;
1503}
1504#endif
1505
Artem Bityutskiy8eab9452010-07-01 18:05:56 +03001506void __init cache_initialize(void)
1507{
1508 INIT_DELAYED_WORK_DEFERRABLE(&cache_cleaner, do_cache_clean);
1509}
1510
Trond Myklebust173912a2009-08-09 15:14:29 -04001511int cache_register(struct cache_detail *cd)
1512{
1513 int ret;
1514
1515 sunrpc_init_cache_detail(cd);
1516 ret = create_cache_proc_entries(cd);
1517 if (ret)
1518 sunrpc_destroy_cache_detail(cd);
1519 return ret;
1520}
1521EXPORT_SYMBOL_GPL(cache_register);
1522
1523void cache_unregister(struct cache_detail *cd)
1524{
1525 remove_cache_proc_entries(cd);
1526 sunrpc_destroy_cache_detail(cd);
1527}
1528EXPORT_SYMBOL_GPL(cache_unregister);
Trond Myklebust8854e822009-08-09 15:14:30 -04001529
1530static ssize_t cache_read_pipefs(struct file *filp, char __user *buf,
1531 size_t count, loff_t *ppos)
1532{
1533 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1534
1535 return cache_read(filp, buf, count, ppos, cd);
1536}
1537
1538static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf,
1539 size_t count, loff_t *ppos)
1540{
1541 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1542
1543 return cache_write(filp, buf, count, ppos, cd);
1544}
1545
1546static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait)
1547{
1548 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1549
1550 return cache_poll(filp, wait, cd);
1551}
1552
Frederic Weisbecker9918ff22010-05-19 15:08:17 +02001553static long cache_ioctl_pipefs(struct file *filp,
Trond Myklebust8854e822009-08-09 15:14:30 -04001554 unsigned int cmd, unsigned long arg)
1555{
Frederic Weisbecker9918ff22010-05-19 15:08:17 +02001556 struct inode *inode = filp->f_dentry->d_inode;
Trond Myklebust8854e822009-08-09 15:14:30 -04001557 struct cache_detail *cd = RPC_I(inode)->private;
Frederic Weisbecker9918ff22010-05-19 15:08:17 +02001558 long ret;
Trond Myklebust8854e822009-08-09 15:14:30 -04001559
Frederic Weisbecker9918ff22010-05-19 15:08:17 +02001560 lock_kernel();
1561 ret = cache_ioctl(inode, filp, cmd, arg, cd);
1562 unlock_kernel();
1563
1564 return ret;
Trond Myklebust8854e822009-08-09 15:14:30 -04001565}
1566
1567static int cache_open_pipefs(struct inode *inode, struct file *filp)
1568{
1569 struct cache_detail *cd = RPC_I(inode)->private;
1570
1571 return cache_open(inode, filp, cd);
1572}
1573
1574static int cache_release_pipefs(struct inode *inode, struct file *filp)
1575{
1576 struct cache_detail *cd = RPC_I(inode)->private;
1577
1578 return cache_release(inode, filp, cd);
1579}
1580
1581const struct file_operations cache_file_operations_pipefs = {
1582 .owner = THIS_MODULE,
1583 .llseek = no_llseek,
1584 .read = cache_read_pipefs,
1585 .write = cache_write_pipefs,
1586 .poll = cache_poll_pipefs,
Frederic Weisbecker9918ff22010-05-19 15:08:17 +02001587 .unlocked_ioctl = cache_ioctl_pipefs, /* for FIONREAD */
Trond Myklebust8854e822009-08-09 15:14:30 -04001588 .open = cache_open_pipefs,
1589 .release = cache_release_pipefs,
1590};
1591
1592static int content_open_pipefs(struct inode *inode, struct file *filp)
1593{
1594 struct cache_detail *cd = RPC_I(inode)->private;
1595
1596 return content_open(inode, filp, cd);
1597}
1598
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001599static int content_release_pipefs(struct inode *inode, struct file *filp)
1600{
1601 struct cache_detail *cd = RPC_I(inode)->private;
1602
1603 return content_release(inode, filp, cd);
1604}
1605
Trond Myklebust8854e822009-08-09 15:14:30 -04001606const struct file_operations content_file_operations_pipefs = {
1607 .open = content_open_pipefs,
1608 .read = seq_read,
1609 .llseek = seq_lseek,
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001610 .release = content_release_pipefs,
Trond Myklebust8854e822009-08-09 15:14:30 -04001611};
1612
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001613static int open_flush_pipefs(struct inode *inode, struct file *filp)
1614{
1615 struct cache_detail *cd = RPC_I(inode)->private;
1616
1617 return open_flush(inode, filp, cd);
1618}
1619
1620static int release_flush_pipefs(struct inode *inode, struct file *filp)
1621{
1622 struct cache_detail *cd = RPC_I(inode)->private;
1623
1624 return release_flush(inode, filp, cd);
1625}
1626
Trond Myklebust8854e822009-08-09 15:14:30 -04001627static ssize_t read_flush_pipefs(struct file *filp, char __user *buf,
1628 size_t count, loff_t *ppos)
1629{
1630 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1631
1632 return read_flush(filp, buf, count, ppos, cd);
1633}
1634
1635static ssize_t write_flush_pipefs(struct file *filp,
1636 const char __user *buf,
1637 size_t count, loff_t *ppos)
1638{
1639 struct cache_detail *cd = RPC_I(filp->f_path.dentry->d_inode)->private;
1640
1641 return write_flush(filp, buf, count, ppos, cd);
1642}
1643
1644const struct file_operations cache_flush_operations_pipefs = {
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001645 .open = open_flush_pipefs,
Trond Myklebust8854e822009-08-09 15:14:30 -04001646 .read = read_flush_pipefs,
1647 .write = write_flush_pipefs,
Trond Myklebustf7e86ab2009-08-19 18:13:00 -04001648 .release = release_flush_pipefs,
Trond Myklebust8854e822009-08-09 15:14:30 -04001649};
1650
1651int sunrpc_cache_register_pipefs(struct dentry *parent,
1652 const char *name, mode_t umode,
1653 struct cache_detail *cd)
1654{
1655 struct qstr q;
1656 struct dentry *dir;
1657 int ret = 0;
1658
1659 sunrpc_init_cache_detail(cd);
1660 q.name = name;
1661 q.len = strlen(name);
1662 q.hash = full_name_hash(q.name, q.len);
1663 dir = rpc_create_cache_dir(parent, &q, umode, cd);
1664 if (!IS_ERR(dir))
1665 cd->u.pipefs.dir = dir;
1666 else {
1667 sunrpc_destroy_cache_detail(cd);
1668 ret = PTR_ERR(dir);
1669 }
1670 return ret;
1671}
1672EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs);
1673
1674void sunrpc_cache_unregister_pipefs(struct cache_detail *cd)
1675{
1676 rpc_remove_cache_dir(cd->u.pipefs.dir);
1677 cd->u.pipefs.dir = NULL;
1678 sunrpc_destroy_cache_detail(cd);
1679}
1680EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs);
1681