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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
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> | |
1b2e122d | 23 | #include <linux/string_helpers.h> |
1da177e4 LT |
24 | #include <asm/uaccess.h> |
25 | #include <linux/poll.h> | |
26 | #include <linux/seq_file.h> | |
27 | #include <linux/proc_fs.h> | |
28 | #include <linux/net.h> | |
29 | #include <linux/workqueue.h> | |
4a3e2f71 | 30 | #include <linux/mutex.h> |
da77005f | 31 | #include <linux/pagemap.h> |
1da177e4 LT |
32 | #include <asm/ioctls.h> |
33 | #include <linux/sunrpc/types.h> | |
34 | #include <linux/sunrpc/cache.h> | |
35 | #include <linux/sunrpc/stats.h> | |
8854e82d | 36 | #include <linux/sunrpc/rpc_pipe_fs.h> |
4f42d0d5 | 37 | #include "netns.h" |
1da177e4 LT |
38 | |
39 | #define RPCDBG_FACILITY RPCDBG_CACHE | |
40 | ||
d76d1815 | 41 | static bool cache_defer_req(struct cache_req *req, struct cache_head *item); |
1da177e4 LT |
42 | static void cache_revisit_request(struct cache_head *item); |
43 | ||
77862036 | 44 | static void cache_init(struct cache_head *h, struct cache_detail *detail) |
1da177e4 | 45 | { |
c5b29f88 | 46 | time_t now = seconds_since_boot(); |
129e5824 | 47 | INIT_HLIST_NODE(&h->cache_list); |
1da177e4 | 48 | h->flags = 0; |
baab935f | 49 | kref_init(&h->ref); |
1da177e4 | 50 | h->expiry_time = now + CACHE_NEW_EXPIRY; |
77862036 NB |
51 | if (now <= detail->flush_time) |
52 | /* ensure it isn't already expired */ | |
53 | now = detail->flush_time + 1; | |
1da177e4 LT |
54 | h->last_refresh = now; |
55 | } | |
56 | ||
15a5f6bd N |
57 | struct cache_head *sunrpc_cache_lookup(struct cache_detail *detail, |
58 | struct cache_head *key, int hash) | |
59 | { | |
129e5824 KM |
60 | struct cache_head *new = NULL, *freeme = NULL, *tmp = NULL; |
61 | struct hlist_head *head; | |
15a5f6bd N |
62 | |
63 | head = &detail->hash_table[hash]; | |
64 | ||
65 | read_lock(&detail->hash_lock); | |
66 | ||
129e5824 | 67 | hlist_for_each_entry(tmp, head, cache_list) { |
15a5f6bd | 68 | if (detail->match(tmp, key)) { |
d202cce8 N |
69 | if (cache_is_expired(detail, tmp)) |
70 | /* This entry is expired, we will discard it. */ | |
71 | break; | |
15a5f6bd N |
72 | cache_get(tmp); |
73 | read_unlock(&detail->hash_lock); | |
74 | return tmp; | |
75 | } | |
76 | } | |
77 | read_unlock(&detail->hash_lock); | |
78 | /* Didn't find anything, insert an empty entry */ | |
79 | ||
80 | new = detail->alloc(); | |
81 | if (!new) | |
82 | return NULL; | |
2f34931f NB |
83 | /* must fully initialise 'new', else |
84 | * we might get lose if we need to | |
85 | * cache_put it soon. | |
86 | */ | |
77862036 | 87 | cache_init(new, detail); |
2f34931f | 88 | detail->init(new, key); |
15a5f6bd N |
89 | |
90 | write_lock(&detail->hash_lock); | |
91 | ||
92 | /* check if entry appeared while we slept */ | |
129e5824 | 93 | hlist_for_each_entry(tmp, head, cache_list) { |
15a5f6bd | 94 | if (detail->match(tmp, key)) { |
d202cce8 | 95 | if (cache_is_expired(detail, tmp)) { |
129e5824 | 96 | hlist_del_init(&tmp->cache_list); |
d202cce8 N |
97 | detail->entries --; |
98 | freeme = tmp; | |
99 | break; | |
100 | } | |
15a5f6bd N |
101 | cache_get(tmp); |
102 | write_unlock(&detail->hash_lock); | |
baab935f | 103 | cache_put(new, detail); |
15a5f6bd N |
104 | return tmp; |
105 | } | |
106 | } | |
129e5824 KM |
107 | |
108 | hlist_add_head(&new->cache_list, head); | |
15a5f6bd N |
109 | detail->entries++; |
110 | cache_get(new); | |
111 | write_unlock(&detail->hash_lock); | |
112 | ||
d202cce8 N |
113 | if (freeme) |
114 | cache_put(freeme, detail); | |
15a5f6bd N |
115 | return new; |
116 | } | |
24c3767e | 117 | EXPORT_SYMBOL_GPL(sunrpc_cache_lookup); |
15a5f6bd | 118 | |
ebd0cb1a | 119 | |
f866a819 | 120 | static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch); |
ebd0cb1a | 121 | |
77862036 NB |
122 | static void cache_fresh_locked(struct cache_head *head, time_t expiry, |
123 | struct cache_detail *detail) | |
ebd0cb1a | 124 | { |
77862036 NB |
125 | time_t now = seconds_since_boot(); |
126 | if (now <= detail->flush_time) | |
127 | /* ensure it isn't immediately treated as expired */ | |
128 | now = detail->flush_time + 1; | |
ebd0cb1a | 129 | head->expiry_time = expiry; |
77862036 | 130 | head->last_refresh = now; |
fdef7aa5 | 131 | smp_wmb(); /* paired with smp_rmb() in cache_is_valid() */ |
908329f2 | 132 | set_bit(CACHE_VALID, &head->flags); |
ebd0cb1a N |
133 | } |
134 | ||
135 | static void cache_fresh_unlocked(struct cache_head *head, | |
908329f2 | 136 | struct cache_detail *detail) |
ebd0cb1a | 137 | { |
ebd0cb1a N |
138 | if (test_and_clear_bit(CACHE_PENDING, &head->flags)) { |
139 | cache_revisit_request(head); | |
f866a819 | 140 | cache_dequeue(detail, head); |
ebd0cb1a N |
141 | } |
142 | } | |
143 | ||
15a5f6bd N |
144 | struct cache_head *sunrpc_cache_update(struct cache_detail *detail, |
145 | struct cache_head *new, struct cache_head *old, int hash) | |
146 | { | |
147 | /* The 'old' entry is to be replaced by 'new'. | |
148 | * If 'old' is not VALID, we update it directly, | |
149 | * otherwise we need to replace it | |
150 | */ | |
15a5f6bd N |
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); | |
77862036 | 160 | cache_fresh_locked(old, new->expiry_time, detail); |
15a5f6bd | 161 | write_unlock(&detail->hash_lock); |
908329f2 | 162 | cache_fresh_unlocked(old, detail); |
15a5f6bd N |
163 | 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) { | |
baab935f | 170 | cache_put(old, detail); |
15a5f6bd N |
171 | return NULL; |
172 | } | |
77862036 | 173 | cache_init(tmp, detail); |
15a5f6bd | 174 | detail->init(tmp, old); |
15a5f6bd N |
175 | |
176 | write_lock(&detail->hash_lock); | |
177 | if (test_bit(CACHE_NEGATIVE, &new->flags)) | |
178 | set_bit(CACHE_NEGATIVE, &tmp->flags); | |
179 | else | |
180 | detail->update(tmp, new); | |
129e5824 | 181 | hlist_add_head(&tmp->cache_list, &detail->hash_table[hash]); |
f2d39586 | 182 | detail->entries++; |
15a5f6bd | 183 | cache_get(tmp); |
77862036 NB |
184 | cache_fresh_locked(tmp, new->expiry_time, detail); |
185 | cache_fresh_locked(old, 0, detail); | |
15a5f6bd | 186 | write_unlock(&detail->hash_lock); |
908329f2 N |
187 | cache_fresh_unlocked(tmp, detail); |
188 | cache_fresh_unlocked(old, detail); | |
baab935f | 189 | cache_put(old, detail); |
15a5f6bd N |
190 | return tmp; |
191 | } | |
24c3767e | 192 | EXPORT_SYMBOL_GPL(sunrpc_cache_update); |
1da177e4 | 193 | |
bc74b4f5 TM |
194 | static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h) |
195 | { | |
2d438338 SK |
196 | if (cd->cache_upcall) |
197 | return cd->cache_upcall(cd, h); | |
21cd1254 | 198 | return sunrpc_cache_pipe_upcall(cd, h); |
bc74b4f5 | 199 | } |
989a19b9 | 200 | |
b6040f97 | 201 | static inline int cache_is_valid(struct cache_head *h) |
989a19b9 | 202 | { |
d202cce8 | 203 | if (!test_bit(CACHE_VALID, &h->flags)) |
989a19b9 N |
204 | return -EAGAIN; |
205 | else { | |
206 | /* entry is valid */ | |
207 | if (test_bit(CACHE_NEGATIVE, &h->flags)) | |
208 | return -ENOENT; | |
fdef7aa5 BF |
209 | else { |
210 | /* | |
211 | * In combination with write barrier in | |
212 | * sunrpc_cache_update, ensures that anyone | |
213 | * using the cache entry after this sees the | |
214 | * updated contents: | |
215 | */ | |
216 | smp_rmb(); | |
989a19b9 | 217 | return 0; |
fdef7aa5 | 218 | } |
989a19b9 N |
219 | } |
220 | } | |
e9dc1221 | 221 | |
6bab93f8 BF |
222 | static int try_to_negate_entry(struct cache_detail *detail, struct cache_head *h) |
223 | { | |
224 | int rv; | |
225 | ||
226 | write_lock(&detail->hash_lock); | |
b6040f97 | 227 | rv = cache_is_valid(h); |
2a1c7f53 N |
228 | if (rv == -EAGAIN) { |
229 | set_bit(CACHE_NEGATIVE, &h->flags); | |
77862036 NB |
230 | cache_fresh_locked(h, seconds_since_boot()+CACHE_NEW_EXPIRY, |
231 | detail); | |
2a1c7f53 | 232 | rv = -ENOENT; |
6bab93f8 | 233 | } |
6bab93f8 BF |
234 | write_unlock(&detail->hash_lock); |
235 | cache_fresh_unlocked(h, detail); | |
2a1c7f53 | 236 | return rv; |
6bab93f8 BF |
237 | } |
238 | ||
1da177e4 LT |
239 | /* |
240 | * This is the generic cache management routine for all | |
241 | * the authentication caches. | |
242 | * It checks the currency of a cache item and will (later) | |
243 | * initiate an upcall to fill it if needed. | |
244 | * | |
245 | * | |
246 | * Returns 0 if the cache_head can be used, or cache_puts it and returns | |
989a19b9 N |
247 | * -EAGAIN if upcall is pending and request has been queued |
248 | * -ETIMEDOUT if upcall failed or request could not be queue or | |
249 | * upcall completed but item is still invalid (implying that | |
250 | * the cache item has been replaced with a newer one). | |
1da177e4 LT |
251 | * -ENOENT if cache entry was negative |
252 | */ | |
253 | int cache_check(struct cache_detail *detail, | |
254 | struct cache_head *h, struct cache_req *rqstp) | |
255 | { | |
256 | int rv; | |
257 | long refresh_age, age; | |
258 | ||
259 | /* First decide return status as best we can */ | |
b6040f97 | 260 | rv = cache_is_valid(h); |
1da177e4 LT |
261 | |
262 | /* now see if we want to start an upcall */ | |
263 | refresh_age = (h->expiry_time - h->last_refresh); | |
c5b29f88 | 264 | age = seconds_since_boot() - h->last_refresh; |
1da177e4 LT |
265 | |
266 | if (rqstp == NULL) { | |
267 | if (rv == -EAGAIN) | |
268 | rv = -ENOENT; | |
0bebc633 N |
269 | } else if (rv == -EAGAIN || |
270 | (h->expiry_time != 0 && age > refresh_age/2)) { | |
46121cf7 CL |
271 | dprintk("RPC: Want update, refage=%ld, age=%ld\n", |
272 | refresh_age, age); | |
1da177e4 LT |
273 | if (!test_and_set_bit(CACHE_PENDING, &h->flags)) { |
274 | switch (cache_make_upcall(detail, h)) { | |
275 | case -EINVAL: | |
6bab93f8 | 276 | rv = try_to_negate_entry(detail, h); |
1da177e4 | 277 | break; |
1da177e4 | 278 | case -EAGAIN: |
2a1c7f53 | 279 | cache_fresh_unlocked(h, detail); |
1da177e4 LT |
280 | break; |
281 | } | |
282 | } | |
283 | } | |
284 | ||
989a19b9 | 285 | if (rv == -EAGAIN) { |
d76d1815 BF |
286 | if (!cache_defer_req(rqstp, h)) { |
287 | /* | |
288 | * Request was not deferred; handle it as best | |
289 | * we can ourselves: | |
290 | */ | |
b6040f97 | 291 | rv = cache_is_valid(h); |
989a19b9 N |
292 | if (rv == -EAGAIN) |
293 | rv = -ETIMEDOUT; | |
294 | } | |
295 | } | |
4013edea | 296 | if (rv) |
baab935f | 297 | cache_put(h, detail); |
1da177e4 LT |
298 | return rv; |
299 | } | |
24c3767e | 300 | EXPORT_SYMBOL_GPL(cache_check); |
1da177e4 | 301 | |
1da177e4 LT |
302 | /* |
303 | * caches need to be periodically cleaned. | |
304 | * For this we maintain a list of cache_detail and | |
305 | * a current pointer into that list and into the table | |
306 | * for that entry. | |
307 | * | |
013920eb | 308 | * Each time cache_clean is called it finds the next non-empty entry |
1da177e4 LT |
309 | * in the current table and walks the list in that entry |
310 | * looking for entries that can be removed. | |
311 | * | |
312 | * An entry gets removed if: | |
313 | * - The expiry is before current time | |
314 | * - The last_refresh time is before the flush_time for that cache | |
315 | * | |
316 | * later we might drop old entries with non-NEVER expiry if that table | |
317 | * is getting 'full' for some definition of 'full' | |
318 | * | |
319 | * The question of "how often to scan a table" is an interesting one | |
320 | * and is answered in part by the use of the "nextcheck" field in the | |
321 | * cache_detail. | |
322 | * When a scan of a table begins, the nextcheck field is set to a time | |
323 | * that is well into the future. | |
324 | * While scanning, if an expiry time is found that is earlier than the | |
325 | * current nextcheck time, nextcheck is set to that expiry time. | |
326 | * If the flush_time is ever set to a time earlier than the nextcheck | |
327 | * time, the nextcheck time is then set to that flush_time. | |
328 | * | |
329 | * A table is then only scanned if the current time is at least | |
330 | * the nextcheck time. | |
cca5172a | 331 | * |
1da177e4 LT |
332 | */ |
333 | ||
334 | static LIST_HEAD(cache_list); | |
335 | static DEFINE_SPINLOCK(cache_list_lock); | |
336 | static struct cache_detail *current_detail; | |
337 | static int current_index; | |
338 | ||
65f27f38 | 339 | static void do_cache_clean(struct work_struct *work); |
8eab945c | 340 | static struct delayed_work cache_cleaner; |
1da177e4 | 341 | |
820f9442 | 342 | void sunrpc_init_cache_detail(struct cache_detail *cd) |
ffe9386b | 343 | { |
1da177e4 LT |
344 | rwlock_init(&cd->hash_lock); |
345 | INIT_LIST_HEAD(&cd->queue); | |
346 | spin_lock(&cache_list_lock); | |
347 | cd->nextcheck = 0; | |
348 | cd->entries = 0; | |
349 | atomic_set(&cd->readers, 0); | |
350 | cd->last_close = 0; | |
351 | cd->last_warn = -1; | |
352 | list_add(&cd->others, &cache_list); | |
353 | spin_unlock(&cache_list_lock); | |
354 | ||
355 | /* start the cleaning process */ | |
77b00bc0 | 356 | queue_delayed_work(system_power_efficient_wq, &cache_cleaner, 0); |
1da177e4 | 357 | } |
820f9442 | 358 | EXPORT_SYMBOL_GPL(sunrpc_init_cache_detail); |
1da177e4 | 359 | |
820f9442 | 360 | void sunrpc_destroy_cache_detail(struct cache_detail *cd) |
1da177e4 LT |
361 | { |
362 | cache_purge(cd); | |
363 | spin_lock(&cache_list_lock); | |
364 | write_lock(&cd->hash_lock); | |
d8d29138 | 365 | if (cd->entries) { |
1da177e4 LT |
366 | write_unlock(&cd->hash_lock); |
367 | spin_unlock(&cache_list_lock); | |
df95a9d4 | 368 | goto out; |
1da177e4 LT |
369 | } |
370 | if (current_detail == cd) | |
371 | current_detail = NULL; | |
372 | list_del_init(&cd->others); | |
373 | write_unlock(&cd->hash_lock); | |
374 | spin_unlock(&cache_list_lock); | |
1da177e4 LT |
375 | if (list_empty(&cache_list)) { |
376 | /* module must be being unloaded so its safe to kill the worker */ | |
4011cd97 | 377 | cancel_delayed_work_sync(&cache_cleaner); |
1da177e4 | 378 | } |
df95a9d4 BF |
379 | return; |
380 | out: | |
ecca063b | 381 | printk(KERN_ERR "RPC: failed to unregister %s cache\n", cd->name); |
1da177e4 | 382 | } |
820f9442 | 383 | EXPORT_SYMBOL_GPL(sunrpc_destroy_cache_detail); |
1da177e4 LT |
384 | |
385 | /* clean cache tries to find something to clean | |
386 | * and cleans it. | |
387 | * It returns 1 if it cleaned something, | |
388 | * 0 if it didn't find anything this time | |
389 | * -1 if it fell off the end of the list. | |
390 | */ | |
391 | static int cache_clean(void) | |
392 | { | |
393 | int rv = 0; | |
394 | struct list_head *next; | |
395 | ||
396 | spin_lock(&cache_list_lock); | |
397 | ||
398 | /* find a suitable table if we don't already have one */ | |
399 | while (current_detail == NULL || | |
400 | current_index >= current_detail->hash_size) { | |
401 | if (current_detail) | |
402 | next = current_detail->others.next; | |
403 | else | |
404 | next = cache_list.next; | |
405 | if (next == &cache_list) { | |
406 | current_detail = NULL; | |
407 | spin_unlock(&cache_list_lock); | |
408 | return -1; | |
409 | } | |
410 | current_detail = list_entry(next, struct cache_detail, others); | |
c5b29f88 | 411 | if (current_detail->nextcheck > seconds_since_boot()) |
1da177e4 LT |
412 | current_index = current_detail->hash_size; |
413 | else { | |
414 | current_index = 0; | |
c5b29f88 | 415 | current_detail->nextcheck = seconds_since_boot()+30*60; |
1da177e4 LT |
416 | } |
417 | } | |
418 | ||
419 | /* find a non-empty bucket in the table */ | |
420 | while (current_detail && | |
421 | current_index < current_detail->hash_size && | |
129e5824 | 422 | hlist_empty(¤t_detail->hash_table[current_index])) |
1da177e4 LT |
423 | current_index++; |
424 | ||
425 | /* find a cleanable entry in the bucket and clean it, or set to next bucket */ | |
cca5172a | 426 | |
1da177e4 | 427 | if (current_detail && current_index < current_detail->hash_size) { |
129e5824 | 428 | struct cache_head *ch = NULL; |
1da177e4 | 429 | struct cache_detail *d; |
129e5824 KM |
430 | struct hlist_head *head; |
431 | struct hlist_node *tmp; | |
cca5172a | 432 | |
1da177e4 LT |
433 | write_lock(¤t_detail->hash_lock); |
434 | ||
435 | /* Ok, now to clean this strand */ | |
cca5172a | 436 | |
129e5824 KM |
437 | head = ¤t_detail->hash_table[current_index]; |
438 | hlist_for_each_entry_safe(ch, tmp, head, cache_list) { | |
1da177e4 LT |
439 | if (current_detail->nextcheck > ch->expiry_time) |
440 | current_detail->nextcheck = ch->expiry_time+1; | |
2f50d8b6 | 441 | if (!cache_is_expired(current_detail, ch)) |
1da177e4 | 442 | continue; |
1da177e4 | 443 | |
129e5824 | 444 | hlist_del_init(&ch->cache_list); |
1da177e4 LT |
445 | current_detail->entries--; |
446 | rv = 1; | |
3af4974e | 447 | break; |
1da177e4 | 448 | } |
3af4974e | 449 | |
1da177e4 LT |
450 | write_unlock(¤t_detail->hash_lock); |
451 | d = current_detail; | |
452 | if (!ch) | |
453 | current_index ++; | |
454 | spin_unlock(&cache_list_lock); | |
5c4d2639 | 455 | if (ch) { |
013920eb | 456 | set_bit(CACHE_CLEANED, &ch->flags); |
2a1c7f53 | 457 | cache_fresh_unlocked(ch, d); |
baab935f | 458 | cache_put(ch, d); |
5c4d2639 | 459 | } |
1da177e4 LT |
460 | } else |
461 | spin_unlock(&cache_list_lock); | |
462 | ||
463 | return rv; | |
464 | } | |
465 | ||
466 | /* | |
467 | * We want to regularly clean the cache, so we need to schedule some work ... | |
468 | */ | |
65f27f38 | 469 | static void do_cache_clean(struct work_struct *work) |
1da177e4 LT |
470 | { |
471 | int delay = 5; | |
472 | if (cache_clean() == -1) | |
6aad89c8 | 473 | delay = round_jiffies_relative(30*HZ); |
1da177e4 LT |
474 | |
475 | if (list_empty(&cache_list)) | |
476 | delay = 0; | |
477 | ||
478 | if (delay) | |
77b00bc0 KW |
479 | queue_delayed_work(system_power_efficient_wq, |
480 | &cache_cleaner, delay); | |
1da177e4 LT |
481 | } |
482 | ||
483 | ||
cca5172a | 484 | /* |
1da177e4 | 485 | * Clean all caches promptly. This just calls cache_clean |
cca5172a | 486 | * repeatedly until we are sure that every cache has had a chance to |
1da177e4 LT |
487 | * be fully cleaned |
488 | */ | |
489 | void cache_flush(void) | |
490 | { | |
491 | while (cache_clean() != -1) | |
492 | cond_resched(); | |
493 | while (cache_clean() != -1) | |
494 | cond_resched(); | |
495 | } | |
24c3767e | 496 | EXPORT_SYMBOL_GPL(cache_flush); |
1da177e4 LT |
497 | |
498 | void cache_purge(struct cache_detail *detail) | |
499 | { | |
77862036 NB |
500 | time_t now = seconds_since_boot(); |
501 | if (detail->flush_time >= now) | |
502 | now = detail->flush_time + 1; | |
503 | /* 'now' is the maximum value any 'last_refresh' can have */ | |
504 | detail->flush_time = now; | |
c5b29f88 | 505 | detail->nextcheck = seconds_since_boot(); |
1da177e4 | 506 | cache_flush(); |
1da177e4 | 507 | } |
24c3767e | 508 | EXPORT_SYMBOL_GPL(cache_purge); |
1da177e4 LT |
509 | |
510 | ||
511 | /* | |
512 | * Deferral and Revisiting of Requests. | |
513 | * | |
514 | * If a cache lookup finds a pending entry, we | |
515 | * need to defer the request and revisit it later. | |
516 | * All deferred requests are stored in a hash table, | |
517 | * indexed by "struct cache_head *". | |
518 | * As it may be wasteful to store a whole request | |
cca5172a | 519 | * structure, we allow the request to provide a |
1da177e4 LT |
520 | * deferred form, which must contain a |
521 | * 'struct cache_deferred_req' | |
522 | * This cache_deferred_req contains a method to allow | |
523 | * it to be revisited when cache info is available | |
524 | */ | |
525 | ||
526 | #define DFR_HASHSIZE (PAGE_SIZE/sizeof(struct list_head)) | |
527 | #define DFR_HASH(item) ((((long)item)>>4 ^ (((long)item)>>13)) % DFR_HASHSIZE) | |
528 | ||
529 | #define DFR_MAX 300 /* ??? */ | |
530 | ||
531 | static DEFINE_SPINLOCK(cache_defer_lock); | |
532 | static LIST_HEAD(cache_defer_list); | |
11174492 | 533 | static struct hlist_head cache_defer_hash[DFR_HASHSIZE]; |
1da177e4 LT |
534 | static int cache_defer_cnt; |
535 | ||
6610f720 BF |
536 | static void __unhash_deferred_req(struct cache_deferred_req *dreq) |
537 | { | |
11174492 | 538 | hlist_del_init(&dreq->hash); |
e33534d5 N |
539 | if (!list_empty(&dreq->recent)) { |
540 | list_del_init(&dreq->recent); | |
541 | cache_defer_cnt--; | |
542 | } | |
6610f720 BF |
543 | } |
544 | ||
545 | static void __hash_deferred_req(struct cache_deferred_req *dreq, struct cache_head *item) | |
1da177e4 | 546 | { |
1da177e4 LT |
547 | int hash = DFR_HASH(item); |
548 | ||
e33534d5 | 549 | INIT_LIST_HEAD(&dreq->recent); |
11174492 | 550 | hlist_add_head(&dreq->hash, &cache_defer_hash[hash]); |
6610f720 BF |
551 | } |
552 | ||
e33534d5 N |
553 | static void setup_deferral(struct cache_deferred_req *dreq, |
554 | struct cache_head *item, | |
555 | int count_me) | |
1da177e4 | 556 | { |
1da177e4 LT |
557 | |
558 | dreq->item = item; | |
1da177e4 LT |
559 | |
560 | spin_lock(&cache_defer_lock); | |
561 | ||
6610f720 | 562 | __hash_deferred_req(dreq, item); |
1da177e4 | 563 | |
e33534d5 N |
564 | if (count_me) { |
565 | cache_defer_cnt++; | |
566 | list_add(&dreq->recent, &cache_defer_list); | |
1da177e4 | 567 | } |
e33534d5 | 568 | |
1da177e4 LT |
569 | spin_unlock(&cache_defer_lock); |
570 | ||
3211af11 | 571 | } |
f16b6e8d | 572 | |
3211af11 BF |
573 | struct thread_deferred_req { |
574 | struct cache_deferred_req handle; | |
575 | struct completion completion; | |
576 | }; | |
577 | ||
578 | static void cache_restart_thread(struct cache_deferred_req *dreq, int too_many) | |
579 | { | |
580 | struct thread_deferred_req *dr = | |
581 | container_of(dreq, struct thread_deferred_req, handle); | |
582 | complete(&dr->completion); | |
583 | } | |
584 | ||
d29068c4 | 585 | static void cache_wait_req(struct cache_req *req, struct cache_head *item) |
3211af11 BF |
586 | { |
587 | struct thread_deferred_req sleeper; | |
588 | struct cache_deferred_req *dreq = &sleeper.handle; | |
3211af11 BF |
589 | |
590 | sleeper.completion = COMPLETION_INITIALIZER_ONSTACK(sleeper.completion); | |
591 | dreq->revisit = cache_restart_thread; | |
592 | ||
e33534d5 | 593 | setup_deferral(dreq, item, 0); |
3211af11 | 594 | |
d29068c4 | 595 | if (!test_bit(CACHE_PENDING, &item->flags) || |
277f68db | 596 | wait_for_completion_interruptible_timeout( |
3211af11 BF |
597 | &sleeper.completion, req->thread_wait) <= 0) { |
598 | /* The completion wasn't completed, so we need | |
599 | * to clean up | |
600 | */ | |
601 | spin_lock(&cache_defer_lock); | |
11174492 | 602 | if (!hlist_unhashed(&sleeper.handle.hash)) { |
3211af11 BF |
603 | __unhash_deferred_req(&sleeper.handle); |
604 | spin_unlock(&cache_defer_lock); | |
605 | } else { | |
606 | /* cache_revisit_request already removed | |
607 | * this from the hash table, but hasn't | |
608 | * called ->revisit yet. It will very soon | |
609 | * and we need to wait for it. | |
f16b6e8d | 610 | */ |
3211af11 BF |
611 | spin_unlock(&cache_defer_lock); |
612 | wait_for_completion(&sleeper.completion); | |
f16b6e8d | 613 | } |
3211af11 | 614 | } |
3211af11 BF |
615 | } |
616 | ||
e33534d5 | 617 | static void cache_limit_defers(void) |
3211af11 | 618 | { |
e33534d5 N |
619 | /* Make sure we haven't exceed the limit of allowed deferred |
620 | * requests. | |
621 | */ | |
622 | struct cache_deferred_req *discard = NULL; | |
3211af11 | 623 | |
e33534d5 N |
624 | if (cache_defer_cnt <= DFR_MAX) |
625 | return; | |
d29068c4 | 626 | |
e33534d5 N |
627 | spin_lock(&cache_defer_lock); |
628 | ||
629 | /* Consider removing either the first or the last */ | |
630 | if (cache_defer_cnt > DFR_MAX) { | |
63862b5b | 631 | if (prandom_u32() & 1) |
e33534d5 N |
632 | discard = list_entry(cache_defer_list.next, |
633 | struct cache_deferred_req, recent); | |
634 | else | |
635 | discard = list_entry(cache_defer_list.prev, | |
636 | struct cache_deferred_req, recent); | |
637 | __unhash_deferred_req(discard); | |
638 | } | |
639 | spin_unlock(&cache_defer_lock); | |
cd68c374 | 640 | if (discard) |
cd68c374 | 641 | discard->revisit(discard, 1); |
e33534d5 | 642 | } |
cd68c374 | 643 | |
d76d1815 BF |
644 | /* Return true if and only if a deferred request is queued. */ |
645 | static bool cache_defer_req(struct cache_req *req, struct cache_head *item) | |
e33534d5 N |
646 | { |
647 | struct cache_deferred_req *dreq; | |
d29068c4 | 648 | |
3211af11 | 649 | if (req->thread_wait) { |
d29068c4 N |
650 | cache_wait_req(req, item); |
651 | if (!test_bit(CACHE_PENDING, &item->flags)) | |
d76d1815 | 652 | return false; |
1da177e4 | 653 | } |
3211af11 BF |
654 | dreq = req->defer(req); |
655 | if (dreq == NULL) | |
d76d1815 | 656 | return false; |
e33534d5 | 657 | setup_deferral(dreq, item, 1); |
d29068c4 N |
658 | if (!test_bit(CACHE_PENDING, &item->flags)) |
659 | /* Bit could have been cleared before we managed to | |
660 | * set up the deferral, so need to revisit just in case | |
661 | */ | |
662 | cache_revisit_request(item); | |
e33534d5 N |
663 | |
664 | cache_limit_defers(); | |
d76d1815 | 665 | return true; |
1da177e4 LT |
666 | } |
667 | ||
668 | static void cache_revisit_request(struct cache_head *item) | |
669 | { | |
670 | struct cache_deferred_req *dreq; | |
671 | struct list_head pending; | |
b67bfe0d | 672 | struct hlist_node *tmp; |
1da177e4 LT |
673 | int hash = DFR_HASH(item); |
674 | ||
675 | INIT_LIST_HEAD(&pending); | |
676 | spin_lock(&cache_defer_lock); | |
cca5172a | 677 | |
b67bfe0d | 678 | hlist_for_each_entry_safe(dreq, tmp, &cache_defer_hash[hash], hash) |
11174492 N |
679 | if (dreq->item == item) { |
680 | __unhash_deferred_req(dreq); | |
681 | list_add(&dreq->recent, &pending); | |
1da177e4 | 682 | } |
11174492 | 683 | |
1da177e4 LT |
684 | spin_unlock(&cache_defer_lock); |
685 | ||
686 | while (!list_empty(&pending)) { | |
687 | dreq = list_entry(pending.next, struct cache_deferred_req, recent); | |
688 | list_del_init(&dreq->recent); | |
689 | dreq->revisit(dreq, 0); | |
690 | } | |
691 | } | |
692 | ||
693 | void cache_clean_deferred(void *owner) | |
694 | { | |
695 | struct cache_deferred_req *dreq, *tmp; | |
696 | struct list_head pending; | |
697 | ||
698 | ||
699 | INIT_LIST_HEAD(&pending); | |
700 | spin_lock(&cache_defer_lock); | |
cca5172a | 701 | |
1da177e4 LT |
702 | list_for_each_entry_safe(dreq, tmp, &cache_defer_list, recent) { |
703 | if (dreq->owner == owner) { | |
6610f720 | 704 | __unhash_deferred_req(dreq); |
e95dffa4 | 705 | list_add(&dreq->recent, &pending); |
1da177e4 LT |
706 | } |
707 | } | |
708 | spin_unlock(&cache_defer_lock); | |
709 | ||
710 | while (!list_empty(&pending)) { | |
711 | dreq = list_entry(pending.next, struct cache_deferred_req, recent); | |
712 | list_del_init(&dreq->recent); | |
713 | dreq->revisit(dreq, 1); | |
714 | } | |
715 | } | |
716 | ||
717 | /* | |
718 | * communicate with user-space | |
719 | * | |
a490c681 BF |
720 | * We have a magic /proc file - /proc/sunrpc/<cachename>/channel. |
721 | * On read, you get a full request, or block. | |
722 | * On write, an update request is processed. | |
723 | * Poll works if anything to read, and always allows write. | |
1da177e4 | 724 | * |
cca5172a | 725 | * Implemented by linked list of requests. Each open file has |
a490c681 | 726 | * a ->private that also exists in this list. New requests are added |
1da177e4 LT |
727 | * to the end and may wakeup and preceding readers. |
728 | * New readers are added to the head. If, on read, an item is found with | |
729 | * CACHE_UPCALLING clear, we free it from the list. | |
730 | * | |
731 | */ | |
732 | ||
733 | static DEFINE_SPINLOCK(queue_lock); | |
4a3e2f71 | 734 | static DEFINE_MUTEX(queue_io_mutex); |
1da177e4 LT |
735 | |
736 | struct cache_queue { | |
737 | struct list_head list; | |
738 | int reader; /* if 0, then request */ | |
739 | }; | |
740 | struct cache_request { | |
741 | struct cache_queue q; | |
742 | struct cache_head *item; | |
743 | char * buf; | |
744 | int len; | |
745 | int readers; | |
746 | }; | |
747 | struct cache_reader { | |
748 | struct cache_queue q; | |
749 | int offset; /* if non-0, we have a refcnt on next request */ | |
750 | }; | |
751 | ||
d94af6de SK |
752 | static int cache_request(struct cache_detail *detail, |
753 | struct cache_request *crq) | |
754 | { | |
755 | char *bp = crq->buf; | |
756 | int len = PAGE_SIZE; | |
757 | ||
758 | detail->cache_request(detail, crq->item, &bp, &len); | |
759 | if (len < 0) | |
760 | return -EAGAIN; | |
761 | return PAGE_SIZE - len; | |
762 | } | |
763 | ||
173912a6 TM |
764 | static ssize_t cache_read(struct file *filp, char __user *buf, size_t count, |
765 | loff_t *ppos, struct cache_detail *cd) | |
1da177e4 LT |
766 | { |
767 | struct cache_reader *rp = filp->private_data; | |
768 | struct cache_request *rq; | |
496ad9aa | 769 | struct inode *inode = file_inode(filp); |
1da177e4 LT |
770 | int err; |
771 | ||
772 | if (count == 0) | |
773 | return 0; | |
774 | ||
5955102c | 775 | inode_lock(inode); /* protect against multiple concurrent |
1da177e4 LT |
776 | * readers on this file */ |
777 | again: | |
778 | spin_lock(&queue_lock); | |
779 | /* need to find next request */ | |
780 | while (rp->q.list.next != &cd->queue && | |
781 | list_entry(rp->q.list.next, struct cache_queue, list) | |
782 | ->reader) { | |
783 | struct list_head *next = rp->q.list.next; | |
784 | list_move(&rp->q.list, next); | |
785 | } | |
786 | if (rp->q.list.next == &cd->queue) { | |
787 | spin_unlock(&queue_lock); | |
5955102c | 788 | inode_unlock(inode); |
0db74d9a | 789 | WARN_ON_ONCE(rp->offset); |
1da177e4 LT |
790 | return 0; |
791 | } | |
792 | rq = container_of(rp->q.list.next, struct cache_request, q.list); | |
0db74d9a | 793 | WARN_ON_ONCE(rq->q.reader); |
1da177e4 LT |
794 | if (rp->offset == 0) |
795 | rq->readers++; | |
796 | spin_unlock(&queue_lock); | |
797 | ||
d94af6de SK |
798 | if (rq->len == 0) { |
799 | err = cache_request(cd, rq); | |
800 | if (err < 0) | |
801 | goto out; | |
802 | rq->len = err; | |
803 | } | |
804 | ||
1da177e4 LT |
805 | if (rp->offset == 0 && !test_bit(CACHE_PENDING, &rq->item->flags)) { |
806 | err = -EAGAIN; | |
807 | spin_lock(&queue_lock); | |
808 | list_move(&rp->q.list, &rq->q.list); | |
809 | spin_unlock(&queue_lock); | |
810 | } else { | |
811 | if (rp->offset + count > rq->len) | |
812 | count = rq->len - rp->offset; | |
813 | err = -EFAULT; | |
814 | if (copy_to_user(buf, rq->buf + rp->offset, count)) | |
815 | goto out; | |
816 | rp->offset += count; | |
817 | if (rp->offset >= rq->len) { | |
818 | rp->offset = 0; | |
819 | spin_lock(&queue_lock); | |
820 | list_move(&rp->q.list, &rq->q.list); | |
821 | spin_unlock(&queue_lock); | |
822 | } | |
823 | err = 0; | |
824 | } | |
825 | out: | |
826 | if (rp->offset == 0) { | |
827 | /* need to release rq */ | |
828 | spin_lock(&queue_lock); | |
829 | rq->readers--; | |
830 | if (rq->readers == 0 && | |
831 | !test_bit(CACHE_PENDING, &rq->item->flags)) { | |
832 | list_del(&rq->q.list); | |
833 | spin_unlock(&queue_lock); | |
baab935f | 834 | cache_put(rq->item, cd); |
1da177e4 LT |
835 | kfree(rq->buf); |
836 | kfree(rq); | |
837 | } else | |
838 | spin_unlock(&queue_lock); | |
839 | } | |
840 | if (err == -EAGAIN) | |
841 | goto again; | |
5955102c | 842 | inode_unlock(inode); |
1da177e4 LT |
843 | return err ? err : count; |
844 | } | |
845 | ||
da77005f TM |
846 | static ssize_t cache_do_downcall(char *kaddr, const char __user *buf, |
847 | size_t count, struct cache_detail *cd) | |
848 | { | |
849 | ssize_t ret; | |
1da177e4 | 850 | |
6d8d1749 DC |
851 | if (count == 0) |
852 | return -EINVAL; | |
da77005f TM |
853 | if (copy_from_user(kaddr, buf, count)) |
854 | return -EFAULT; | |
855 | kaddr[count] = '\0'; | |
856 | ret = cd->cache_parse(cd, kaddr, count); | |
857 | if (!ret) | |
858 | ret = count; | |
859 | return ret; | |
860 | } | |
861 | ||
862 | static ssize_t cache_slow_downcall(const char __user *buf, | |
863 | size_t count, struct cache_detail *cd) | |
1da177e4 | 864 | { |
da77005f TM |
865 | static char write_buf[8192]; /* protected by queue_io_mutex */ |
866 | ssize_t ret = -EINVAL; | |
1da177e4 | 867 | |
1da177e4 | 868 | if (count >= sizeof(write_buf)) |
da77005f | 869 | goto out; |
4a3e2f71 | 870 | mutex_lock(&queue_io_mutex); |
da77005f TM |
871 | ret = cache_do_downcall(write_buf, buf, count, cd); |
872 | mutex_unlock(&queue_io_mutex); | |
873 | out: | |
874 | return ret; | |
875 | } | |
1da177e4 | 876 | |
da77005f TM |
877 | static ssize_t cache_downcall(struct address_space *mapping, |
878 | const char __user *buf, | |
879 | size_t count, struct cache_detail *cd) | |
880 | { | |
881 | struct page *page; | |
882 | char *kaddr; | |
883 | ssize_t ret = -ENOMEM; | |
884 | ||
09cbfeaf | 885 | if (count >= PAGE_SIZE) |
da77005f TM |
886 | goto out_slow; |
887 | ||
888 | page = find_or_create_page(mapping, 0, GFP_KERNEL); | |
889 | if (!page) | |
890 | goto out_slow; | |
891 | ||
892 | kaddr = kmap(page); | |
893 | ret = cache_do_downcall(kaddr, buf, count, cd); | |
894 | kunmap(page); | |
895 | unlock_page(page); | |
09cbfeaf | 896 | put_page(page); |
da77005f TM |
897 | return ret; |
898 | out_slow: | |
899 | return cache_slow_downcall(buf, count, cd); | |
900 | } | |
1da177e4 | 901 | |
173912a6 TM |
902 | static ssize_t cache_write(struct file *filp, const char __user *buf, |
903 | size_t count, loff_t *ppos, | |
904 | struct cache_detail *cd) | |
da77005f TM |
905 | { |
906 | struct address_space *mapping = filp->f_mapping; | |
496ad9aa | 907 | struct inode *inode = file_inode(filp); |
da77005f TM |
908 | ssize_t ret = -EINVAL; |
909 | ||
910 | if (!cd->cache_parse) | |
911 | goto out; | |
912 | ||
5955102c | 913 | inode_lock(inode); |
da77005f | 914 | ret = cache_downcall(mapping, buf, count, cd); |
5955102c | 915 | inode_unlock(inode); |
da77005f TM |
916 | out: |
917 | return ret; | |
1da177e4 LT |
918 | } |
919 | ||
920 | static DECLARE_WAIT_QUEUE_HEAD(queue_wait); | |
921 | ||
173912a6 TM |
922 | static unsigned int cache_poll(struct file *filp, poll_table *wait, |
923 | struct cache_detail *cd) | |
1da177e4 LT |
924 | { |
925 | unsigned int mask; | |
926 | struct cache_reader *rp = filp->private_data; | |
927 | struct cache_queue *cq; | |
1da177e4 LT |
928 | |
929 | poll_wait(filp, &queue_wait, wait); | |
930 | ||
931 | /* alway allow write */ | |
1711fd9a | 932 | mask = POLLOUT | POLLWRNORM; |
1da177e4 LT |
933 | |
934 | if (!rp) | |
935 | return mask; | |
936 | ||
937 | spin_lock(&queue_lock); | |
938 | ||
939 | for (cq= &rp->q; &cq->list != &cd->queue; | |
940 | cq = list_entry(cq->list.next, struct cache_queue, list)) | |
941 | if (!cq->reader) { | |
942 | mask |= POLLIN | POLLRDNORM; | |
943 | break; | |
944 | } | |
945 | spin_unlock(&queue_lock); | |
946 | return mask; | |
947 | } | |
948 | ||
173912a6 TM |
949 | static int cache_ioctl(struct inode *ino, struct file *filp, |
950 | unsigned int cmd, unsigned long arg, | |
951 | struct cache_detail *cd) | |
1da177e4 LT |
952 | { |
953 | int len = 0; | |
954 | struct cache_reader *rp = filp->private_data; | |
955 | struct cache_queue *cq; | |
1da177e4 LT |
956 | |
957 | if (cmd != FIONREAD || !rp) | |
958 | return -EINVAL; | |
959 | ||
960 | spin_lock(&queue_lock); | |
961 | ||
962 | /* only find the length remaining in current request, | |
963 | * or the length of the next request | |
964 | */ | |
965 | for (cq= &rp->q; &cq->list != &cd->queue; | |
966 | cq = list_entry(cq->list.next, struct cache_queue, list)) | |
967 | if (!cq->reader) { | |
968 | struct cache_request *cr = | |
969 | container_of(cq, struct cache_request, q); | |
970 | len = cr->len - rp->offset; | |
971 | break; | |
972 | } | |
973 | spin_unlock(&queue_lock); | |
974 | ||
975 | return put_user(len, (int __user *)arg); | |
976 | } | |
977 | ||
173912a6 TM |
978 | static int cache_open(struct inode *inode, struct file *filp, |
979 | struct cache_detail *cd) | |
1da177e4 LT |
980 | { |
981 | struct cache_reader *rp = NULL; | |
982 | ||
f7e86ab9 TM |
983 | if (!cd || !try_module_get(cd->owner)) |
984 | return -EACCES; | |
1da177e4 LT |
985 | nonseekable_open(inode, filp); |
986 | if (filp->f_mode & FMODE_READ) { | |
1da177e4 | 987 | rp = kmalloc(sizeof(*rp), GFP_KERNEL); |
a7823c79 AK |
988 | if (!rp) { |
989 | module_put(cd->owner); | |
1da177e4 | 990 | return -ENOMEM; |
a7823c79 | 991 | } |
1da177e4 LT |
992 | rp->offset = 0; |
993 | rp->q.reader = 1; | |
994 | atomic_inc(&cd->readers); | |
995 | spin_lock(&queue_lock); | |
996 | list_add(&rp->q.list, &cd->queue); | |
997 | spin_unlock(&queue_lock); | |
998 | } | |
999 | filp->private_data = rp; | |
1000 | return 0; | |
1001 | } | |
1002 | ||
173912a6 TM |
1003 | static int cache_release(struct inode *inode, struct file *filp, |
1004 | struct cache_detail *cd) | |
1da177e4 LT |
1005 | { |
1006 | struct cache_reader *rp = filp->private_data; | |
1da177e4 LT |
1007 | |
1008 | if (rp) { | |
1009 | spin_lock(&queue_lock); | |
1010 | if (rp->offset) { | |
1011 | struct cache_queue *cq; | |
1012 | for (cq= &rp->q; &cq->list != &cd->queue; | |
1013 | cq = list_entry(cq->list.next, struct cache_queue, list)) | |
1014 | if (!cq->reader) { | |
1015 | container_of(cq, struct cache_request, q) | |
1016 | ->readers--; | |
1017 | break; | |
1018 | } | |
1019 | rp->offset = 0; | |
1020 | } | |
1021 | list_del(&rp->q.list); | |
1022 | spin_unlock(&queue_lock); | |
1023 | ||
1024 | filp->private_data = NULL; | |
1025 | kfree(rp); | |
1026 | ||
c5b29f88 | 1027 | cd->last_close = seconds_since_boot(); |
1da177e4 LT |
1028 | atomic_dec(&cd->readers); |
1029 | } | |
f7e86ab9 | 1030 | module_put(cd->owner); |
1da177e4 LT |
1031 | return 0; |
1032 | } | |
1033 | ||
1034 | ||
1035 | ||
f866a819 | 1036 | static void cache_dequeue(struct cache_detail *detail, struct cache_head *ch) |
1da177e4 | 1037 | { |
f9e1aedc N |
1038 | struct cache_queue *cq, *tmp; |
1039 | struct cache_request *cr; | |
1040 | struct list_head dequeued; | |
1041 | ||
1042 | INIT_LIST_HEAD(&dequeued); | |
1da177e4 | 1043 | spin_lock(&queue_lock); |
f9e1aedc | 1044 | list_for_each_entry_safe(cq, tmp, &detail->queue, list) |
1da177e4 | 1045 | if (!cq->reader) { |
f9e1aedc | 1046 | cr = container_of(cq, struct cache_request, q); |
1da177e4 LT |
1047 | if (cr->item != ch) |
1048 | continue; | |
f9e1aedc N |
1049 | if (test_bit(CACHE_PENDING, &ch->flags)) |
1050 | /* Lost a race and it is pending again */ | |
1051 | break; | |
1da177e4 | 1052 | if (cr->readers != 0) |
4013edea | 1053 | continue; |
f9e1aedc | 1054 | list_move(&cr->q.list, &dequeued); |
1da177e4 LT |
1055 | } |
1056 | spin_unlock(&queue_lock); | |
f9e1aedc N |
1057 | while (!list_empty(&dequeued)) { |
1058 | cr = list_entry(dequeued.next, struct cache_request, q.list); | |
1059 | list_del(&cr->q.list); | |
1060 | cache_put(cr->item, detail); | |
1061 | kfree(cr->buf); | |
1062 | kfree(cr); | |
1063 | } | |
1da177e4 LT |
1064 | } |
1065 | ||
1066 | /* | |
1067 | * Support routines for text-based upcalls. | |
1068 | * Fields are separated by spaces. | |
1069 | * Fields are either mangled to quote space tab newline slosh with slosh | |
1070 | * or a hexified with a leading \x | |
1071 | * Record is terminated with newline. | |
1072 | * | |
1073 | */ | |
1074 | ||
1075 | void qword_add(char **bpp, int *lp, char *str) | |
1076 | { | |
1077 | char *bp = *bpp; | |
1078 | int len = *lp; | |
1b2e122d | 1079 | int ret; |
1da177e4 LT |
1080 | |
1081 | if (len < 0) return; | |
1082 | ||
41416f23 RV |
1083 | ret = string_escape_str(str, bp, len, ESCAPE_OCTAL, "\\ \n\t"); |
1084 | if (ret >= len) { | |
1085 | bp += len; | |
1b2e122d | 1086 | len = -1; |
41416f23 RV |
1087 | } else { |
1088 | bp += ret; | |
1b2e122d | 1089 | len -= ret; |
1da177e4 LT |
1090 | *bp++ = ' '; |
1091 | len--; | |
1092 | } | |
1093 | *bpp = bp; | |
1094 | *lp = len; | |
1095 | } | |
24c3767e | 1096 | EXPORT_SYMBOL_GPL(qword_add); |
1da177e4 LT |
1097 | |
1098 | void qword_addhex(char **bpp, int *lp, char *buf, int blen) | |
1099 | { | |
1100 | char *bp = *bpp; | |
1101 | int len = *lp; | |
1102 | ||
1103 | if (len < 0) return; | |
1104 | ||
1105 | if (len > 2) { | |
1106 | *bp++ = '\\'; | |
1107 | *bp++ = 'x'; | |
1108 | len -= 2; | |
1109 | while (blen && len >= 2) { | |
056785ea | 1110 | bp = hex_byte_pack(bp, *buf++); |
1da177e4 LT |
1111 | len -= 2; |
1112 | blen--; | |
1113 | } | |
1114 | } | |
1115 | if (blen || len<1) len = -1; | |
1116 | else { | |
1117 | *bp++ = ' '; | |
1118 | len--; | |
1119 | } | |
1120 | *bpp = bp; | |
1121 | *lp = len; | |
1122 | } | |
24c3767e | 1123 | EXPORT_SYMBOL_GPL(qword_addhex); |
1da177e4 LT |
1124 | |
1125 | static void warn_no_listener(struct cache_detail *detail) | |
1126 | { | |
1127 | if (detail->last_warn != detail->last_close) { | |
1128 | detail->last_warn = detail->last_close; | |
1129 | if (detail->warn_no_listener) | |
2da8ca26 | 1130 | detail->warn_no_listener(detail, detail->last_close != 0); |
1da177e4 LT |
1131 | } |
1132 | } | |
1133 | ||
06497524 BF |
1134 | static bool cache_listeners_exist(struct cache_detail *detail) |
1135 | { | |
1136 | if (atomic_read(&detail->readers)) | |
1137 | return true; | |
1138 | if (detail->last_close == 0) | |
1139 | /* This cache was never opened */ | |
1140 | return false; | |
1141 | if (detail->last_close < seconds_since_boot() - 30) | |
1142 | /* | |
1143 | * We allow for the possibility that someone might | |
1144 | * restart a userspace daemon without restarting the | |
1145 | * server; but after 30 seconds, we give up. | |
1146 | */ | |
1147 | return false; | |
1148 | return true; | |
1149 | } | |
1150 | ||
1da177e4 | 1151 | /* |
bc74b4f5 TM |
1152 | * register an upcall request to user-space and queue it up for read() by the |
1153 | * upcall daemon. | |
1154 | * | |
1da177e4 LT |
1155 | * Each request is at most one page long. |
1156 | */ | |
21cd1254 | 1157 | int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h) |
1da177e4 LT |
1158 | { |
1159 | ||
1160 | char *buf; | |
1161 | struct cache_request *crq; | |
f9e1aedc | 1162 | int ret = 0; |
1da177e4 | 1163 | |
2d438338 SK |
1164 | if (!detail->cache_request) |
1165 | return -EINVAL; | |
1da177e4 | 1166 | |
06497524 BF |
1167 | if (!cache_listeners_exist(detail)) { |
1168 | warn_no_listener(detail); | |
1169 | return -EINVAL; | |
1da177e4 | 1170 | } |
013920eb N |
1171 | if (test_bit(CACHE_CLEANED, &h->flags)) |
1172 | /* Too late to make an upcall */ | |
1173 | return -EAGAIN; | |
1da177e4 LT |
1174 | |
1175 | buf = kmalloc(PAGE_SIZE, GFP_KERNEL); | |
1176 | if (!buf) | |
1177 | return -EAGAIN; | |
1178 | ||
1179 | crq = kmalloc(sizeof (*crq), GFP_KERNEL); | |
1180 | if (!crq) { | |
1181 | kfree(buf); | |
1182 | return -EAGAIN; | |
1183 | } | |
1184 | ||
1da177e4 | 1185 | crq->q.reader = 0; |
1da177e4 | 1186 | crq->buf = buf; |
d94af6de | 1187 | crq->len = 0; |
1da177e4 LT |
1188 | crq->readers = 0; |
1189 | spin_lock(&queue_lock); | |
a6ab1e81 N |
1190 | if (test_bit(CACHE_PENDING, &h->flags)) { |
1191 | crq->item = cache_get(h); | |
f9e1aedc | 1192 | list_add_tail(&crq->q.list, &detail->queue); |
a6ab1e81 | 1193 | } else |
f9e1aedc N |
1194 | /* Lost a race, no longer PENDING, so don't enqueue */ |
1195 | ret = -EAGAIN; | |
1da177e4 LT |
1196 | spin_unlock(&queue_lock); |
1197 | wake_up(&queue_wait); | |
f9e1aedc N |
1198 | if (ret == -EAGAIN) { |
1199 | kfree(buf); | |
1200 | kfree(crq); | |
1201 | } | |
1202 | return ret; | |
1da177e4 | 1203 | } |
bc74b4f5 | 1204 | EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall); |
1da177e4 LT |
1205 | |
1206 | /* | |
1207 | * parse a message from user-space and pass it | |
1208 | * to an appropriate cache | |
1209 | * Messages are, like requests, separated into fields by | |
1210 | * spaces and dequotes as \xHEXSTRING or embedded \nnn octal | |
1211 | * | |
cca5172a | 1212 | * Message is |
1da177e4 LT |
1213 | * reply cachename expiry key ... content.... |
1214 | * | |
cca5172a | 1215 | * key and content are both parsed by cache |
1da177e4 LT |
1216 | */ |
1217 | ||
1da177e4 LT |
1218 | int qword_get(char **bpp, char *dest, int bufsize) |
1219 | { | |
1220 | /* return bytes copied, or -1 on error */ | |
1221 | char *bp = *bpp; | |
1222 | int len = 0; | |
1223 | ||
1224 | while (*bp == ' ') bp++; | |
1225 | ||
1226 | if (bp[0] == '\\' && bp[1] == 'x') { | |
1227 | /* HEX STRING */ | |
1228 | bp += 2; | |
b7052cd7 | 1229 | while (len < bufsize - 1) { |
e7f483ea AS |
1230 | int h, l; |
1231 | ||
1232 | h = hex_to_bin(bp[0]); | |
1233 | if (h < 0) | |
1234 | break; | |
1235 | ||
1236 | l = hex_to_bin(bp[1]); | |
1237 | if (l < 0) | |
1238 | break; | |
1239 | ||
1240 | *dest++ = (h << 4) | l; | |
1241 | bp += 2; | |
1da177e4 LT |
1242 | len++; |
1243 | } | |
1244 | } else { | |
1245 | /* text with \nnn octal quoting */ | |
1246 | while (*bp != ' ' && *bp != '\n' && *bp && len < bufsize-1) { | |
1247 | if (*bp == '\\' && | |
1248 | isodigit(bp[1]) && (bp[1] <= '3') && | |
1249 | isodigit(bp[2]) && | |
1250 | isodigit(bp[3])) { | |
1251 | int byte = (*++bp -'0'); | |
1252 | bp++; | |
1253 | byte = (byte << 3) | (*bp++ - '0'); | |
1254 | byte = (byte << 3) | (*bp++ - '0'); | |
1255 | *dest++ = byte; | |
1256 | len++; | |
1257 | } else { | |
1258 | *dest++ = *bp++; | |
1259 | len++; | |
1260 | } | |
1261 | } | |
1262 | } | |
1263 | ||
1264 | if (*bp != ' ' && *bp != '\n' && *bp != '\0') | |
1265 | return -1; | |
1266 | while (*bp == ' ') bp++; | |
1267 | *bpp = bp; | |
1268 | *dest = '\0'; | |
1269 | return len; | |
1270 | } | |
24c3767e | 1271 | EXPORT_SYMBOL_GPL(qword_get); |
1da177e4 LT |
1272 | |
1273 | ||
1274 | /* | |
1275 | * support /proc/sunrpc/cache/$CACHENAME/content | |
1276 | * as a seqfile. | |
1277 | * We call ->cache_show passing NULL for the item to | |
1278 | * get a header, then pass each real item in the cache | |
1279 | */ | |
1280 | ||
c8c081b7 | 1281 | void *cache_seq_start(struct seq_file *m, loff_t *pos) |
9a429c49 | 1282 | __acquires(cd->hash_lock) |
1da177e4 LT |
1283 | { |
1284 | loff_t n = *pos; | |
95c96174 | 1285 | unsigned int hash, entry; |
1da177e4 | 1286 | struct cache_head *ch; |
9936f2ae | 1287 | struct cache_detail *cd = m->private; |
1da177e4 LT |
1288 | |
1289 | read_lock(&cd->hash_lock); | |
1290 | if (!n--) | |
1291 | return SEQ_START_TOKEN; | |
1292 | hash = n >> 32; | |
1293 | entry = n & ((1LL<<32) - 1); | |
1294 | ||
129e5824 | 1295 | hlist_for_each_entry(ch, &cd->hash_table[hash], cache_list) |
1da177e4 LT |
1296 | if (!entry--) |
1297 | return ch; | |
1298 | n &= ~((1LL<<32) - 1); | |
1299 | do { | |
1300 | hash++; | |
1301 | n += 1LL<<32; | |
cca5172a | 1302 | } while(hash < cd->hash_size && |
129e5824 | 1303 | hlist_empty(&cd->hash_table[hash])); |
1da177e4 LT |
1304 | if (hash >= cd->hash_size) |
1305 | return NULL; | |
1306 | *pos = n+1; | |
129e5824 KM |
1307 | return hlist_entry_safe(cd->hash_table[hash].first, |
1308 | struct cache_head, cache_list); | |
1da177e4 | 1309 | } |
c8c081b7 | 1310 | EXPORT_SYMBOL_GPL(cache_seq_start); |
1da177e4 | 1311 | |
c8c081b7 | 1312 | void *cache_seq_next(struct seq_file *m, void *p, loff_t *pos) |
1da177e4 LT |
1313 | { |
1314 | struct cache_head *ch = p; | |
1315 | int hash = (*pos >> 32); | |
9936f2ae | 1316 | struct cache_detail *cd = m->private; |
1da177e4 LT |
1317 | |
1318 | if (p == SEQ_START_TOKEN) | |
1319 | hash = 0; | |
129e5824 | 1320 | else if (ch->cache_list.next == NULL) { |
1da177e4 LT |
1321 | hash++; |
1322 | *pos += 1LL<<32; | |
1323 | } else { | |
1324 | ++*pos; | |
129e5824 KM |
1325 | return hlist_entry_safe(ch->cache_list.next, |
1326 | struct cache_head, cache_list); | |
1da177e4 LT |
1327 | } |
1328 | *pos &= ~((1LL<<32) - 1); | |
1329 | while (hash < cd->hash_size && | |
129e5824 | 1330 | hlist_empty(&cd->hash_table[hash])) { |
1da177e4 LT |
1331 | hash++; |
1332 | *pos += 1LL<<32; | |
1333 | } | |
1334 | if (hash >= cd->hash_size) | |
1335 | return NULL; | |
1336 | ++*pos; | |
129e5824 KM |
1337 | return hlist_entry_safe(cd->hash_table[hash].first, |
1338 | struct cache_head, cache_list); | |
1da177e4 | 1339 | } |
c8c081b7 | 1340 | EXPORT_SYMBOL_GPL(cache_seq_next); |
1da177e4 | 1341 | |
c8c081b7 | 1342 | void cache_seq_stop(struct seq_file *m, void *p) |
9a429c49 | 1343 | __releases(cd->hash_lock) |
1da177e4 | 1344 | { |
9936f2ae | 1345 | struct cache_detail *cd = m->private; |
1da177e4 LT |
1346 | read_unlock(&cd->hash_lock); |
1347 | } | |
c8c081b7 | 1348 | EXPORT_SYMBOL_GPL(cache_seq_stop); |
1da177e4 LT |
1349 | |
1350 | static int c_show(struct seq_file *m, void *p) | |
1351 | { | |
1352 | struct cache_head *cp = p; | |
9936f2ae | 1353 | struct cache_detail *cd = m->private; |
1da177e4 LT |
1354 | |
1355 | if (p == SEQ_START_TOKEN) | |
1356 | return cd->cache_show(m, cd, NULL); | |
1357 | ||
1358 | ifdebug(CACHE) | |
4013edea | 1359 | seq_printf(m, "# expiry=%ld refcnt=%d flags=%lx\n", |
c5b29f88 N |
1360 | convert_to_wallclock(cp->expiry_time), |
1361 | atomic_read(&cp->ref.refcount), cp->flags); | |
1da177e4 LT |
1362 | cache_get(cp); |
1363 | if (cache_check(cd, cp, NULL)) | |
1364 | /* cache_check does a cache_put on failure */ | |
1365 | seq_printf(m, "# "); | |
200724a7 N |
1366 | else { |
1367 | if (cache_is_expired(cd, cp)) | |
1368 | seq_printf(m, "# "); | |
1da177e4 | 1369 | cache_put(cp, cd); |
200724a7 | 1370 | } |
1da177e4 LT |
1371 | |
1372 | return cd->cache_show(m, cd, cp); | |
1373 | } | |
1374 | ||
56b3d975 | 1375 | static const struct seq_operations cache_content_op = { |
c8c081b7 KM |
1376 | .start = cache_seq_start, |
1377 | .next = cache_seq_next, | |
1378 | .stop = cache_seq_stop, | |
1da177e4 LT |
1379 | .show = c_show, |
1380 | }; | |
1381 | ||
173912a6 TM |
1382 | static int content_open(struct inode *inode, struct file *file, |
1383 | struct cache_detail *cd) | |
1da177e4 | 1384 | { |
9936f2ae KM |
1385 | struct seq_file *seq; |
1386 | int err; | |
1da177e4 | 1387 | |
f7e86ab9 TM |
1388 | if (!cd || !try_module_get(cd->owner)) |
1389 | return -EACCES; | |
9936f2ae KM |
1390 | |
1391 | err = seq_open(file, &cache_content_op); | |
1392 | if (err) { | |
a5990ea1 | 1393 | module_put(cd->owner); |
9936f2ae | 1394 | return err; |
a5990ea1 | 1395 | } |
1da177e4 | 1396 | |
9936f2ae KM |
1397 | seq = file->private_data; |
1398 | seq->private = cd; | |
ec931035 | 1399 | return 0; |
1da177e4 | 1400 | } |
1da177e4 | 1401 | |
f7e86ab9 TM |
1402 | static int content_release(struct inode *inode, struct file *file, |
1403 | struct cache_detail *cd) | |
1404 | { | |
9936f2ae | 1405 | int ret = seq_release(inode, file); |
f7e86ab9 TM |
1406 | module_put(cd->owner); |
1407 | return ret; | |
1408 | } | |
1409 | ||
1410 | static int open_flush(struct inode *inode, struct file *file, | |
1411 | struct cache_detail *cd) | |
1412 | { | |
1413 | if (!cd || !try_module_get(cd->owner)) | |
1414 | return -EACCES; | |
1415 | return nonseekable_open(inode, file); | |
1416 | } | |
1417 | ||
1418 | static int release_flush(struct inode *inode, struct file *file, | |
1419 | struct cache_detail *cd) | |
1420 | { | |
1421 | module_put(cd->owner); | |
1422 | return 0; | |
1423 | } | |
1da177e4 LT |
1424 | |
1425 | static ssize_t read_flush(struct file *file, char __user *buf, | |
173912a6 TM |
1426 | size_t count, loff_t *ppos, |
1427 | struct cache_detail *cd) | |
1da177e4 | 1428 | { |
212ba906 | 1429 | char tbuf[22]; |
1da177e4 | 1430 | unsigned long p = *ppos; |
01b2969a | 1431 | size_t len; |
1da177e4 | 1432 | |
212ba906 | 1433 | snprintf(tbuf, sizeof(tbuf), "%lu\n", convert_to_wallclock(cd->flush_time)); |
1da177e4 LT |
1434 | len = strlen(tbuf); |
1435 | if (p >= len) | |
1436 | return 0; | |
1437 | len -= p; | |
01b2969a CL |
1438 | if (len > count) |
1439 | len = count; | |
1da177e4 | 1440 | if (copy_to_user(buf, (void*)(tbuf+p), len)) |
01b2969a CL |
1441 | return -EFAULT; |
1442 | *ppos += len; | |
1da177e4 LT |
1443 | return len; |
1444 | } | |
1445 | ||
173912a6 TM |
1446 | static ssize_t write_flush(struct file *file, const char __user *buf, |
1447 | size_t count, loff_t *ppos, | |
1448 | struct cache_detail *cd) | |
1da177e4 | 1449 | { |
1da177e4 | 1450 | char tbuf[20]; |
c5b29f88 | 1451 | char *bp, *ep; |
77862036 | 1452 | time_t then, now; |
c5b29f88 | 1453 | |
1da177e4 LT |
1454 | if (*ppos || count > sizeof(tbuf)-1) |
1455 | return -EINVAL; | |
1456 | if (copy_from_user(tbuf, buf, count)) | |
1457 | return -EFAULT; | |
1458 | tbuf[count] = 0; | |
c5b29f88 | 1459 | simple_strtoul(tbuf, &ep, 0); |
1da177e4 LT |
1460 | if (*ep && *ep != '\n') |
1461 | return -EINVAL; | |
1462 | ||
c5b29f88 | 1463 | bp = tbuf; |
77862036 NB |
1464 | then = get_expiry(&bp); |
1465 | now = seconds_since_boot(); | |
1466 | cd->nextcheck = now; | |
1467 | /* Can only set flush_time to 1 second beyond "now", or | |
1468 | * possibly 1 second beyond flushtime. This is because | |
1469 | * flush_time never goes backwards so it mustn't get too far | |
1470 | * ahead of time. | |
1471 | */ | |
1472 | if (then >= now) { | |
1473 | /* Want to flush everything, so behave like cache_purge() */ | |
1474 | if (cd->flush_time >= now) | |
1475 | now = cd->flush_time + 1; | |
1476 | then = now; | |
1477 | } | |
1478 | ||
1479 | cd->flush_time = then; | |
1da177e4 LT |
1480 | cache_flush(); |
1481 | ||
1482 | *ppos += count; | |
1483 | return count; | |
1484 | } | |
1485 | ||
173912a6 TM |
1486 | static ssize_t cache_read_procfs(struct file *filp, char __user *buf, |
1487 | size_t count, loff_t *ppos) | |
1488 | { | |
d9dda78b | 1489 | struct cache_detail *cd = PDE_DATA(file_inode(filp)); |
173912a6 TM |
1490 | |
1491 | return cache_read(filp, buf, count, ppos, cd); | |
1492 | } | |
1493 | ||
1494 | static ssize_t cache_write_procfs(struct file *filp, const char __user *buf, | |
1495 | size_t count, loff_t *ppos) | |
1496 | { | |
d9dda78b | 1497 | struct cache_detail *cd = PDE_DATA(file_inode(filp)); |
173912a6 TM |
1498 | |
1499 | return cache_write(filp, buf, count, ppos, cd); | |
1500 | } | |
1501 | ||
1502 | static unsigned int cache_poll_procfs(struct file *filp, poll_table *wait) | |
1503 | { | |
d9dda78b | 1504 | struct cache_detail *cd = PDE_DATA(file_inode(filp)); |
173912a6 TM |
1505 | |
1506 | return cache_poll(filp, wait, cd); | |
1507 | } | |
1508 | ||
d79b6f4d FW |
1509 | static long cache_ioctl_procfs(struct file *filp, |
1510 | unsigned int cmd, unsigned long arg) | |
173912a6 | 1511 | { |
496ad9aa | 1512 | struct inode *inode = file_inode(filp); |
d9dda78b | 1513 | struct cache_detail *cd = PDE_DATA(inode); |
173912a6 | 1514 | |
a6f8dbc6 | 1515 | return cache_ioctl(inode, filp, cmd, arg, cd); |
173912a6 TM |
1516 | } |
1517 | ||
1518 | static int cache_open_procfs(struct inode *inode, struct file *filp) | |
1519 | { | |
d9dda78b | 1520 | struct cache_detail *cd = PDE_DATA(inode); |
173912a6 TM |
1521 | |
1522 | return cache_open(inode, filp, cd); | |
1523 | } | |
1524 | ||
1525 | static int cache_release_procfs(struct inode *inode, struct file *filp) | |
1526 | { | |
d9dda78b | 1527 | struct cache_detail *cd = PDE_DATA(inode); |
173912a6 TM |
1528 | |
1529 | return cache_release(inode, filp, cd); | |
1530 | } | |
1531 | ||
1532 | static const struct file_operations cache_file_operations_procfs = { | |
1533 | .owner = THIS_MODULE, | |
1534 | .llseek = no_llseek, | |
1535 | .read = cache_read_procfs, | |
1536 | .write = cache_write_procfs, | |
1537 | .poll = cache_poll_procfs, | |
d79b6f4d | 1538 | .unlocked_ioctl = cache_ioctl_procfs, /* for FIONREAD */ |
173912a6 TM |
1539 | .open = cache_open_procfs, |
1540 | .release = cache_release_procfs, | |
1da177e4 | 1541 | }; |
173912a6 TM |
1542 | |
1543 | static int content_open_procfs(struct inode *inode, struct file *filp) | |
1544 | { | |
d9dda78b | 1545 | struct cache_detail *cd = PDE_DATA(inode); |
173912a6 TM |
1546 | |
1547 | return content_open(inode, filp, cd); | |
1548 | } | |
1549 | ||
f7e86ab9 TM |
1550 | static int content_release_procfs(struct inode *inode, struct file *filp) |
1551 | { | |
d9dda78b | 1552 | struct cache_detail *cd = PDE_DATA(inode); |
f7e86ab9 TM |
1553 | |
1554 | return content_release(inode, filp, cd); | |
1555 | } | |
1556 | ||
173912a6 TM |
1557 | static const struct file_operations content_file_operations_procfs = { |
1558 | .open = content_open_procfs, | |
1559 | .read = seq_read, | |
1560 | .llseek = seq_lseek, | |
f7e86ab9 | 1561 | .release = content_release_procfs, |
173912a6 TM |
1562 | }; |
1563 | ||
f7e86ab9 TM |
1564 | static int open_flush_procfs(struct inode *inode, struct file *filp) |
1565 | { | |
d9dda78b | 1566 | struct cache_detail *cd = PDE_DATA(inode); |
f7e86ab9 TM |
1567 | |
1568 | return open_flush(inode, filp, cd); | |
1569 | } | |
1570 | ||
1571 | static int release_flush_procfs(struct inode *inode, struct file *filp) | |
1572 | { | |
d9dda78b | 1573 | struct cache_detail *cd = PDE_DATA(inode); |
f7e86ab9 TM |
1574 | |
1575 | return release_flush(inode, filp, cd); | |
1576 | } | |
1577 | ||
173912a6 TM |
1578 | static ssize_t read_flush_procfs(struct file *filp, char __user *buf, |
1579 | size_t count, loff_t *ppos) | |
1580 | { | |
d9dda78b | 1581 | struct cache_detail *cd = PDE_DATA(file_inode(filp)); |
173912a6 TM |
1582 | |
1583 | return read_flush(filp, buf, count, ppos, cd); | |
1584 | } | |
1585 | ||
1586 | static ssize_t write_flush_procfs(struct file *filp, | |
1587 | const char __user *buf, | |
1588 | size_t count, loff_t *ppos) | |
1589 | { | |
d9dda78b | 1590 | struct cache_detail *cd = PDE_DATA(file_inode(filp)); |
173912a6 TM |
1591 | |
1592 | return write_flush(filp, buf, count, ppos, cd); | |
1593 | } | |
1594 | ||
1595 | static const struct file_operations cache_flush_operations_procfs = { | |
f7e86ab9 | 1596 | .open = open_flush_procfs, |
173912a6 TM |
1597 | .read = read_flush_procfs, |
1598 | .write = write_flush_procfs, | |
f7e86ab9 | 1599 | .release = release_flush_procfs, |
6038f373 | 1600 | .llseek = no_llseek, |
1da177e4 | 1601 | }; |
173912a6 | 1602 | |
593ce16b | 1603 | static void remove_cache_proc_entries(struct cache_detail *cd, struct net *net) |
173912a6 | 1604 | { |
4f42d0d5 PE |
1605 | struct sunrpc_net *sn; |
1606 | ||
173912a6 TM |
1607 | if (cd->u.procfs.proc_ent == NULL) |
1608 | return; | |
1609 | if (cd->u.procfs.flush_ent) | |
1610 | remove_proc_entry("flush", cd->u.procfs.proc_ent); | |
1611 | if (cd->u.procfs.channel_ent) | |
1612 | remove_proc_entry("channel", cd->u.procfs.proc_ent); | |
1613 | if (cd->u.procfs.content_ent) | |
1614 | remove_proc_entry("content", cd->u.procfs.proc_ent); | |
1615 | cd->u.procfs.proc_ent = NULL; | |
4f42d0d5 PE |
1616 | sn = net_generic(net, sunrpc_net_id); |
1617 | remove_proc_entry(cd->name, sn->proc_net_rpc); | |
173912a6 TM |
1618 | } |
1619 | ||
1620 | #ifdef CONFIG_PROC_FS | |
593ce16b | 1621 | static int create_cache_proc_entries(struct cache_detail *cd, struct net *net) |
173912a6 TM |
1622 | { |
1623 | struct proc_dir_entry *p; | |
4f42d0d5 | 1624 | struct sunrpc_net *sn; |
173912a6 | 1625 | |
4f42d0d5 PE |
1626 | sn = net_generic(net, sunrpc_net_id); |
1627 | cd->u.procfs.proc_ent = proc_mkdir(cd->name, sn->proc_net_rpc); | |
173912a6 TM |
1628 | if (cd->u.procfs.proc_ent == NULL) |
1629 | goto out_nomem; | |
1630 | cd->u.procfs.channel_ent = NULL; | |
1631 | cd->u.procfs.content_ent = NULL; | |
1632 | ||
1633 | p = proc_create_data("flush", S_IFREG|S_IRUSR|S_IWUSR, | |
1634 | cd->u.procfs.proc_ent, | |
1635 | &cache_flush_operations_procfs, cd); | |
1636 | cd->u.procfs.flush_ent = p; | |
1637 | if (p == NULL) | |
1638 | goto out_nomem; | |
1639 | ||
2d438338 | 1640 | if (cd->cache_request || cd->cache_parse) { |
173912a6 TM |
1641 | p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR, |
1642 | cd->u.procfs.proc_ent, | |
1643 | &cache_file_operations_procfs, cd); | |
1644 | cd->u.procfs.channel_ent = p; | |
1645 | if (p == NULL) | |
1646 | goto out_nomem; | |
1647 | } | |
1648 | if (cd->cache_show) { | |
ec168676 | 1649 | p = proc_create_data("content", S_IFREG|S_IRUSR, |
173912a6 TM |
1650 | cd->u.procfs.proc_ent, |
1651 | &content_file_operations_procfs, cd); | |
1652 | cd->u.procfs.content_ent = p; | |
1653 | if (p == NULL) | |
1654 | goto out_nomem; | |
1655 | } | |
1656 | return 0; | |
1657 | out_nomem: | |
593ce16b | 1658 | remove_cache_proc_entries(cd, net); |
173912a6 TM |
1659 | return -ENOMEM; |
1660 | } | |
1661 | #else /* CONFIG_PROC_FS */ | |
593ce16b | 1662 | static int create_cache_proc_entries(struct cache_detail *cd, struct net *net) |
173912a6 TM |
1663 | { |
1664 | return 0; | |
1665 | } | |
1666 | #endif | |
1667 | ||
8eab945c AB |
1668 | void __init cache_initialize(void) |
1669 | { | |
203b42f7 | 1670 | INIT_DEFERRABLE_WORK(&cache_cleaner, do_cache_clean); |
8eab945c AB |
1671 | } |
1672 | ||
593ce16b | 1673 | int cache_register_net(struct cache_detail *cd, struct net *net) |
173912a6 TM |
1674 | { |
1675 | int ret; | |
1676 | ||
1677 | sunrpc_init_cache_detail(cd); | |
593ce16b | 1678 | ret = create_cache_proc_entries(cd, net); |
173912a6 TM |
1679 | if (ret) |
1680 | sunrpc_destroy_cache_detail(cd); | |
1681 | return ret; | |
1682 | } | |
f5c8593b | 1683 | EXPORT_SYMBOL_GPL(cache_register_net); |
593ce16b | 1684 | |
593ce16b | 1685 | void cache_unregister_net(struct cache_detail *cd, struct net *net) |
173912a6 | 1686 | { |
593ce16b | 1687 | remove_cache_proc_entries(cd, net); |
173912a6 TM |
1688 | sunrpc_destroy_cache_detail(cd); |
1689 | } | |
f5c8593b | 1690 | EXPORT_SYMBOL_GPL(cache_unregister_net); |
593ce16b | 1691 | |
0a402d5a SK |
1692 | struct cache_detail *cache_create_net(struct cache_detail *tmpl, struct net *net) |
1693 | { | |
1694 | struct cache_detail *cd; | |
129e5824 | 1695 | int i; |
0a402d5a SK |
1696 | |
1697 | cd = kmemdup(tmpl, sizeof(struct cache_detail), GFP_KERNEL); | |
1698 | if (cd == NULL) | |
1699 | return ERR_PTR(-ENOMEM); | |
1700 | ||
129e5824 | 1701 | cd->hash_table = kzalloc(cd->hash_size * sizeof(struct hlist_head), |
0a402d5a SK |
1702 | GFP_KERNEL); |
1703 | if (cd->hash_table == NULL) { | |
1704 | kfree(cd); | |
1705 | return ERR_PTR(-ENOMEM); | |
1706 | } | |
129e5824 KM |
1707 | |
1708 | for (i = 0; i < cd->hash_size; i++) | |
1709 | INIT_HLIST_HEAD(&cd->hash_table[i]); | |
0a402d5a SK |
1710 | cd->net = net; |
1711 | return cd; | |
1712 | } | |
1713 | EXPORT_SYMBOL_GPL(cache_create_net); | |
1714 | ||
1715 | void cache_destroy_net(struct cache_detail *cd, struct net *net) | |
593ce16b | 1716 | { |
0a402d5a SK |
1717 | kfree(cd->hash_table); |
1718 | kfree(cd); | |
593ce16b | 1719 | } |
0a402d5a | 1720 | EXPORT_SYMBOL_GPL(cache_destroy_net); |
8854e82d TM |
1721 | |
1722 | static ssize_t cache_read_pipefs(struct file *filp, char __user *buf, | |
1723 | size_t count, loff_t *ppos) | |
1724 | { | |
496ad9aa | 1725 | struct cache_detail *cd = RPC_I(file_inode(filp))->private; |
8854e82d TM |
1726 | |
1727 | return cache_read(filp, buf, count, ppos, cd); | |
1728 | } | |
1729 | ||
1730 | static ssize_t cache_write_pipefs(struct file *filp, const char __user *buf, | |
1731 | size_t count, loff_t *ppos) | |
1732 | { | |
496ad9aa | 1733 | struct cache_detail *cd = RPC_I(file_inode(filp))->private; |
8854e82d TM |
1734 | |
1735 | return cache_write(filp, buf, count, ppos, cd); | |
1736 | } | |
1737 | ||
1738 | static unsigned int cache_poll_pipefs(struct file *filp, poll_table *wait) | |
1739 | { | |
496ad9aa | 1740 | struct cache_detail *cd = RPC_I(file_inode(filp))->private; |
8854e82d TM |
1741 | |
1742 | return cache_poll(filp, wait, cd); | |
1743 | } | |
1744 | ||
9918ff26 | 1745 | static long cache_ioctl_pipefs(struct file *filp, |
8854e82d TM |
1746 | unsigned int cmd, unsigned long arg) |
1747 | { | |
496ad9aa | 1748 | struct inode *inode = file_inode(filp); |
8854e82d TM |
1749 | struct cache_detail *cd = RPC_I(inode)->private; |
1750 | ||
a6f8dbc6 | 1751 | return cache_ioctl(inode, filp, cmd, arg, cd); |
8854e82d TM |
1752 | } |
1753 | ||
1754 | static int cache_open_pipefs(struct inode *inode, struct file *filp) | |
1755 | { | |
1756 | struct cache_detail *cd = RPC_I(inode)->private; | |
1757 | ||
1758 | return cache_open(inode, filp, cd); | |
1759 | } | |
1760 | ||
1761 | static int cache_release_pipefs(struct inode *inode, struct file *filp) | |
1762 | { | |
1763 | struct cache_detail *cd = RPC_I(inode)->private; | |
1764 | ||
1765 | return cache_release(inode, filp, cd); | |
1766 | } | |
1767 | ||
1768 | const struct file_operations cache_file_operations_pipefs = { | |
1769 | .owner = THIS_MODULE, | |
1770 | .llseek = no_llseek, | |
1771 | .read = cache_read_pipefs, | |
1772 | .write = cache_write_pipefs, | |
1773 | .poll = cache_poll_pipefs, | |
9918ff26 | 1774 | .unlocked_ioctl = cache_ioctl_pipefs, /* for FIONREAD */ |
8854e82d TM |
1775 | .open = cache_open_pipefs, |
1776 | .release = cache_release_pipefs, | |
1777 | }; | |
1778 | ||
1779 | static int content_open_pipefs(struct inode *inode, struct file *filp) | |
1780 | { | |
1781 | struct cache_detail *cd = RPC_I(inode)->private; | |
1782 | ||
1783 | return content_open(inode, filp, cd); | |
1784 | } | |
1785 | ||
f7e86ab9 TM |
1786 | static int content_release_pipefs(struct inode *inode, struct file *filp) |
1787 | { | |
1788 | struct cache_detail *cd = RPC_I(inode)->private; | |
1789 | ||
1790 | return content_release(inode, filp, cd); | |
1791 | } | |
1792 | ||
8854e82d TM |
1793 | const struct file_operations content_file_operations_pipefs = { |
1794 | .open = content_open_pipefs, | |
1795 | .read = seq_read, | |
1796 | .llseek = seq_lseek, | |
f7e86ab9 | 1797 | .release = content_release_pipefs, |
8854e82d TM |
1798 | }; |
1799 | ||
f7e86ab9 TM |
1800 | static int open_flush_pipefs(struct inode *inode, struct file *filp) |
1801 | { | |
1802 | struct cache_detail *cd = RPC_I(inode)->private; | |
1803 | ||
1804 | return open_flush(inode, filp, cd); | |
1805 | } | |
1806 | ||
1807 | static int release_flush_pipefs(struct inode *inode, struct file *filp) | |
1808 | { | |
1809 | struct cache_detail *cd = RPC_I(inode)->private; | |
1810 | ||
1811 | return release_flush(inode, filp, cd); | |
1812 | } | |
1813 | ||
8854e82d TM |
1814 | static ssize_t read_flush_pipefs(struct file *filp, char __user *buf, |
1815 | size_t count, loff_t *ppos) | |
1816 | { | |
496ad9aa | 1817 | struct cache_detail *cd = RPC_I(file_inode(filp))->private; |
8854e82d TM |
1818 | |
1819 | return read_flush(filp, buf, count, ppos, cd); | |
1820 | } | |
1821 | ||
1822 | static ssize_t write_flush_pipefs(struct file *filp, | |
1823 | const char __user *buf, | |
1824 | size_t count, loff_t *ppos) | |
1825 | { | |
496ad9aa | 1826 | struct cache_detail *cd = RPC_I(file_inode(filp))->private; |
8854e82d TM |
1827 | |
1828 | return write_flush(filp, buf, count, ppos, cd); | |
1829 | } | |
1830 | ||
1831 | const struct file_operations cache_flush_operations_pipefs = { | |
f7e86ab9 | 1832 | .open = open_flush_pipefs, |
8854e82d TM |
1833 | .read = read_flush_pipefs, |
1834 | .write = write_flush_pipefs, | |
f7e86ab9 | 1835 | .release = release_flush_pipefs, |
6038f373 | 1836 | .llseek = no_llseek, |
8854e82d TM |
1837 | }; |
1838 | ||
1839 | int sunrpc_cache_register_pipefs(struct dentry *parent, | |
64f1426f | 1840 | const char *name, umode_t umode, |
8854e82d TM |
1841 | struct cache_detail *cd) |
1842 | { | |
a95e691f AV |
1843 | struct dentry *dir = rpc_create_cache_dir(parent, name, umode, cd); |
1844 | if (IS_ERR(dir)) | |
1845 | return PTR_ERR(dir); | |
1846 | cd->u.pipefs.dir = dir; | |
1847 | return 0; | |
8854e82d TM |
1848 | } |
1849 | EXPORT_SYMBOL_GPL(sunrpc_cache_register_pipefs); | |
1850 | ||
1851 | void sunrpc_cache_unregister_pipefs(struct cache_detail *cd) | |
1852 | { | |
1853 | rpc_remove_cache_dir(cd->u.pipefs.dir); | |
1854 | cd->u.pipefs.dir = NULL; | |
8854e82d TM |
1855 | } |
1856 | EXPORT_SYMBOL_GPL(sunrpc_cache_unregister_pipefs); | |
1857 |