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b5108822 DH |
1 | /* Cache page management and data I/O routines |
2 | * | |
3 | * Copyright (C) 2004-2008 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public License | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the License, or (at your option) any later version. | |
10 | */ | |
11 | ||
12 | #define FSCACHE_DEBUG_LEVEL PAGE | |
13 | #include <linux/module.h> | |
14 | #include <linux/fscache-cache.h> | |
15 | #include <linux/buffer_head.h> | |
16 | #include <linux/pagevec.h> | |
5a0e3ad6 | 17 | #include <linux/slab.h> |
b5108822 DH |
18 | #include "internal.h" |
19 | ||
20 | /* | |
21 | * check to see if a page is being written to the cache | |
22 | */ | |
23 | bool __fscache_check_page_write(struct fscache_cookie *cookie, struct page *page) | |
24 | { | |
25 | void *val; | |
26 | ||
27 | rcu_read_lock(); | |
28 | val = radix_tree_lookup(&cookie->stores, page->index); | |
29 | rcu_read_unlock(); | |
30 | ||
31 | return val != NULL; | |
32 | } | |
33 | EXPORT_SYMBOL(__fscache_check_page_write); | |
34 | ||
35 | /* | |
36 | * wait for a page to finish being written to the cache | |
37 | */ | |
38 | void __fscache_wait_on_page_write(struct fscache_cookie *cookie, struct page *page) | |
39 | { | |
40 | wait_queue_head_t *wq = bit_waitqueue(&cookie->flags, 0); | |
41 | ||
42 | wait_event(*wq, !__fscache_check_page_write(cookie, page)); | |
43 | } | |
44 | EXPORT_SYMBOL(__fscache_wait_on_page_write); | |
45 | ||
201a1542 DH |
46 | /* |
47 | * decide whether a page can be released, possibly by cancelling a store to it | |
48 | * - we're allowed to sleep if __GFP_WAIT is flagged | |
49 | */ | |
50 | bool __fscache_maybe_release_page(struct fscache_cookie *cookie, | |
51 | struct page *page, | |
52 | gfp_t gfp) | |
53 | { | |
54 | struct page *xpage; | |
55 | void *val; | |
56 | ||
57 | _enter("%p,%p,%x", cookie, page, gfp); | |
58 | ||
8c209ce7 | 59 | try_again: |
201a1542 DH |
60 | rcu_read_lock(); |
61 | val = radix_tree_lookup(&cookie->stores, page->index); | |
62 | if (!val) { | |
63 | rcu_read_unlock(); | |
64 | fscache_stat(&fscache_n_store_vmscan_not_storing); | |
65 | __fscache_uncache_page(cookie, page); | |
66 | return true; | |
67 | } | |
68 | ||
69 | /* see if the page is actually undergoing storage - if so we can't get | |
70 | * rid of it till the cache has finished with it */ | |
71 | if (radix_tree_tag_get(&cookie->stores, page->index, | |
72 | FSCACHE_COOKIE_STORING_TAG)) { | |
73 | rcu_read_unlock(); | |
74 | goto page_busy; | |
75 | } | |
76 | ||
77 | /* the page is pending storage, so we attempt to cancel the store and | |
78 | * discard the store request so that the page can be reclaimed */ | |
79 | spin_lock(&cookie->stores_lock); | |
80 | rcu_read_unlock(); | |
81 | ||
82 | if (radix_tree_tag_get(&cookie->stores, page->index, | |
83 | FSCACHE_COOKIE_STORING_TAG)) { | |
84 | /* the page started to undergo storage whilst we were looking, | |
85 | * so now we can only wait or return */ | |
86 | spin_unlock(&cookie->stores_lock); | |
87 | goto page_busy; | |
88 | } | |
89 | ||
90 | xpage = radix_tree_delete(&cookie->stores, page->index); | |
91 | spin_unlock(&cookie->stores_lock); | |
92 | ||
93 | if (xpage) { | |
94 | fscache_stat(&fscache_n_store_vmscan_cancelled); | |
95 | fscache_stat(&fscache_n_store_radix_deletes); | |
96 | ASSERTCMP(xpage, ==, page); | |
97 | } else { | |
98 | fscache_stat(&fscache_n_store_vmscan_gone); | |
99 | } | |
100 | ||
101 | wake_up_bit(&cookie->flags, 0); | |
102 | if (xpage) | |
103 | page_cache_release(xpage); | |
104 | __fscache_uncache_page(cookie, page); | |
105 | return true; | |
106 | ||
107 | page_busy: | |
8c209ce7 DH |
108 | /* We will wait here if we're allowed to, but that could deadlock the |
109 | * allocator as the work threads writing to the cache may all end up | |
110 | * sleeping on memory allocation, so we may need to impose a timeout | |
111 | * too. */ | |
112 | if (!(gfp & __GFP_WAIT)) { | |
113 | fscache_stat(&fscache_n_store_vmscan_busy); | |
114 | return false; | |
115 | } | |
116 | ||
117 | fscache_stat(&fscache_n_store_vmscan_wait); | |
118 | __fscache_wait_on_page_write(cookie, page); | |
119 | gfp &= ~__GFP_WAIT; | |
120 | goto try_again; | |
201a1542 DH |
121 | } |
122 | EXPORT_SYMBOL(__fscache_maybe_release_page); | |
123 | ||
b5108822 DH |
124 | /* |
125 | * note that a page has finished being written to the cache | |
126 | */ | |
1bccf513 DH |
127 | static void fscache_end_page_write(struct fscache_object *object, |
128 | struct page *page) | |
b5108822 | 129 | { |
1bccf513 DH |
130 | struct fscache_cookie *cookie; |
131 | struct page *xpage = NULL; | |
b5108822 | 132 | |
1bccf513 DH |
133 | spin_lock(&object->lock); |
134 | cookie = object->cookie; | |
135 | if (cookie) { | |
136 | /* delete the page from the tree if it is now no longer | |
137 | * pending */ | |
138 | spin_lock(&cookie->stores_lock); | |
201a1542 DH |
139 | radix_tree_tag_clear(&cookie->stores, page->index, |
140 | FSCACHE_COOKIE_STORING_TAG); | |
285e728b DH |
141 | if (!radix_tree_tag_get(&cookie->stores, page->index, |
142 | FSCACHE_COOKIE_PENDING_TAG)) { | |
143 | fscache_stat(&fscache_n_store_radix_deletes); | |
144 | xpage = radix_tree_delete(&cookie->stores, page->index); | |
145 | } | |
1bccf513 DH |
146 | spin_unlock(&cookie->stores_lock); |
147 | wake_up_bit(&cookie->flags, 0); | |
148 | } | |
149 | spin_unlock(&object->lock); | |
150 | if (xpage) | |
151 | page_cache_release(xpage); | |
b5108822 DH |
152 | } |
153 | ||
154 | /* | |
155 | * actually apply the changed attributes to a cache object | |
156 | */ | |
157 | static void fscache_attr_changed_op(struct fscache_operation *op) | |
158 | { | |
159 | struct fscache_object *object = op->object; | |
440f0aff | 160 | int ret; |
b5108822 DH |
161 | |
162 | _enter("{OBJ%x OP%x}", object->debug_id, op->debug_id); | |
163 | ||
164 | fscache_stat(&fscache_n_attr_changed_calls); | |
165 | ||
440f0aff | 166 | if (fscache_object_is_active(object)) { |
52bd75fd | 167 | fscache_stat(&fscache_n_cop_attr_changed); |
440f0aff | 168 | ret = object->cache->ops->attr_changed(object); |
52bd75fd | 169 | fscache_stat_d(&fscache_n_cop_attr_changed); |
440f0aff DH |
170 | if (ret < 0) |
171 | fscache_abort_object(object); | |
172 | } | |
b5108822 | 173 | |
9f10523f | 174 | fscache_op_complete(op); |
b5108822 DH |
175 | _leave(""); |
176 | } | |
177 | ||
178 | /* | |
179 | * notification that the attributes on an object have changed | |
180 | */ | |
181 | int __fscache_attr_changed(struct fscache_cookie *cookie) | |
182 | { | |
183 | struct fscache_operation *op; | |
184 | struct fscache_object *object; | |
185 | ||
186 | _enter("%p", cookie); | |
187 | ||
188 | ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); | |
189 | ||
190 | fscache_stat(&fscache_n_attr_changed); | |
191 | ||
192 | op = kzalloc(sizeof(*op), GFP_KERNEL); | |
193 | if (!op) { | |
194 | fscache_stat(&fscache_n_attr_changed_nomem); | |
195 | _leave(" = -ENOMEM"); | |
196 | return -ENOMEM; | |
197 | } | |
198 | ||
8af7c124 TH |
199 | fscache_operation_init(op, fscache_attr_changed_op, NULL); |
200 | op->flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_EXCLUSIVE); | |
b5108822 DH |
201 | |
202 | spin_lock(&cookie->lock); | |
203 | ||
204 | if (hlist_empty(&cookie->backing_objects)) | |
205 | goto nobufs; | |
206 | object = hlist_entry(cookie->backing_objects.first, | |
207 | struct fscache_object, cookie_link); | |
208 | ||
209 | if (fscache_submit_exclusive_op(object, op) < 0) | |
210 | goto nobufs; | |
211 | spin_unlock(&cookie->lock); | |
212 | fscache_stat(&fscache_n_attr_changed_ok); | |
213 | fscache_put_operation(op); | |
214 | _leave(" = 0"); | |
215 | return 0; | |
216 | ||
217 | nobufs: | |
218 | spin_unlock(&cookie->lock); | |
219 | kfree(op); | |
220 | fscache_stat(&fscache_n_attr_changed_nobufs); | |
221 | _leave(" = %d", -ENOBUFS); | |
222 | return -ENOBUFS; | |
223 | } | |
224 | EXPORT_SYMBOL(__fscache_attr_changed); | |
225 | ||
b5108822 DH |
226 | /* |
227 | * release a retrieval op reference | |
228 | */ | |
229 | static void fscache_release_retrieval_op(struct fscache_operation *_op) | |
230 | { | |
231 | struct fscache_retrieval *op = | |
232 | container_of(_op, struct fscache_retrieval, op); | |
233 | ||
234 | _enter("{OP%x}", op->op.debug_id); | |
235 | ||
9f10523f DH |
236 | ASSERTCMP(op->n_pages, ==, 0); |
237 | ||
b5108822 DH |
238 | fscache_hist(fscache_retrieval_histogram, op->start_time); |
239 | if (op->context) | |
240 | fscache_put_context(op->op.object->cookie, op->context); | |
241 | ||
242 | _leave(""); | |
243 | } | |
244 | ||
245 | /* | |
246 | * allocate a retrieval op | |
247 | */ | |
248 | static struct fscache_retrieval *fscache_alloc_retrieval( | |
249 | struct address_space *mapping, | |
250 | fscache_rw_complete_t end_io_func, | |
251 | void *context) | |
252 | { | |
253 | struct fscache_retrieval *op; | |
254 | ||
255 | /* allocate a retrieval operation and attempt to submit it */ | |
256 | op = kzalloc(sizeof(*op), GFP_NOIO); | |
257 | if (!op) { | |
258 | fscache_stat(&fscache_n_retrievals_nomem); | |
259 | return NULL; | |
260 | } | |
261 | ||
8af7c124 | 262 | fscache_operation_init(&op->op, NULL, fscache_release_retrieval_op); |
b5108822 DH |
263 | op->op.flags = FSCACHE_OP_MYTHREAD | (1 << FSCACHE_OP_WAITING); |
264 | op->mapping = mapping; | |
265 | op->end_io_func = end_io_func; | |
266 | op->context = context; | |
267 | op->start_time = jiffies; | |
b5108822 DH |
268 | INIT_LIST_HEAD(&op->to_do); |
269 | return op; | |
270 | } | |
271 | ||
272 | /* | |
273 | * wait for a deferred lookup to complete | |
274 | */ | |
275 | static int fscache_wait_for_deferred_lookup(struct fscache_cookie *cookie) | |
276 | { | |
277 | unsigned long jif; | |
278 | ||
279 | _enter(""); | |
280 | ||
281 | if (!test_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags)) { | |
282 | _leave(" = 0 [imm]"); | |
283 | return 0; | |
284 | } | |
285 | ||
286 | fscache_stat(&fscache_n_retrievals_wait); | |
287 | ||
288 | jif = jiffies; | |
289 | if (wait_on_bit(&cookie->flags, FSCACHE_COOKIE_LOOKING_UP, | |
290 | fscache_wait_bit_interruptible, | |
291 | TASK_INTERRUPTIBLE) != 0) { | |
292 | fscache_stat(&fscache_n_retrievals_intr); | |
293 | _leave(" = -ERESTARTSYS"); | |
294 | return -ERESTARTSYS; | |
295 | } | |
296 | ||
297 | ASSERT(!test_bit(FSCACHE_COOKIE_LOOKING_UP, &cookie->flags)); | |
298 | ||
299 | smp_rmb(); | |
300 | fscache_hist(fscache_retrieval_delay_histogram, jif); | |
301 | _leave(" = 0 [dly]"); | |
302 | return 0; | |
303 | } | |
304 | ||
60d543ca DH |
305 | /* |
306 | * wait for an object to become active (or dead) | |
307 | */ | |
308 | static int fscache_wait_for_retrieval_activation(struct fscache_object *object, | |
309 | struct fscache_retrieval *op, | |
310 | atomic_t *stat_op_waits, | |
311 | atomic_t *stat_object_dead) | |
312 | { | |
313 | int ret; | |
314 | ||
315 | if (!test_bit(FSCACHE_OP_WAITING, &op->op.flags)) | |
316 | goto check_if_dead; | |
317 | ||
318 | _debug(">>> WT"); | |
319 | fscache_stat(stat_op_waits); | |
320 | if (wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING, | |
321 | fscache_wait_bit_interruptible, | |
9c04caa8 | 322 | TASK_INTERRUPTIBLE) != 0) { |
60d543ca DH |
323 | ret = fscache_cancel_op(&op->op); |
324 | if (ret == 0) | |
325 | return -ERESTARTSYS; | |
326 | ||
327 | /* it's been removed from the pending queue by another party, | |
328 | * so we should get to run shortly */ | |
329 | wait_on_bit(&op->op.flags, FSCACHE_OP_WAITING, | |
330 | fscache_wait_bit, TASK_UNINTERRUPTIBLE); | |
331 | } | |
332 | _debug("<<< GO"); | |
333 | ||
334 | check_if_dead: | |
9f10523f DH |
335 | if (op->op.state == FSCACHE_OP_ST_CANCELLED) { |
336 | fscache_stat(stat_object_dead); | |
337 | _leave(" = -ENOBUFS [cancelled]"); | |
338 | return -ENOBUFS; | |
339 | } | |
60d543ca | 340 | if (unlikely(fscache_object_is_dead(object))) { |
b4cf1e08 DH |
341 | pr_err("%s() = -ENOBUFS [obj dead %d]", __func__, op->op.state); |
342 | fscache_cancel_op(&op->op); | |
60d543ca DH |
343 | fscache_stat(stat_object_dead); |
344 | return -ENOBUFS; | |
345 | } | |
346 | return 0; | |
347 | } | |
348 | ||
b5108822 DH |
349 | /* |
350 | * read a page from the cache or allocate a block in which to store it | |
351 | * - we return: | |
352 | * -ENOMEM - out of memory, nothing done | |
353 | * -ERESTARTSYS - interrupted | |
354 | * -ENOBUFS - no backing object available in which to cache the block | |
355 | * -ENODATA - no data available in the backing object for this block | |
356 | * 0 - dispatched a read - it'll call end_io_func() when finished | |
357 | */ | |
358 | int __fscache_read_or_alloc_page(struct fscache_cookie *cookie, | |
359 | struct page *page, | |
360 | fscache_rw_complete_t end_io_func, | |
361 | void *context, | |
362 | gfp_t gfp) | |
363 | { | |
364 | struct fscache_retrieval *op; | |
365 | struct fscache_object *object; | |
366 | int ret; | |
367 | ||
368 | _enter("%p,%p,,,", cookie, page); | |
369 | ||
370 | fscache_stat(&fscache_n_retrievals); | |
371 | ||
372 | if (hlist_empty(&cookie->backing_objects)) | |
373 | goto nobufs; | |
374 | ||
ef778e7a DH |
375 | if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { |
376 | _leave(" = -ENOBUFS [invalidating]"); | |
377 | return -ENOBUFS; | |
378 | } | |
379 | ||
b5108822 DH |
380 | ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); |
381 | ASSERTCMP(page, !=, NULL); | |
382 | ||
383 | if (fscache_wait_for_deferred_lookup(cookie) < 0) | |
384 | return -ERESTARTSYS; | |
385 | ||
386 | op = fscache_alloc_retrieval(page->mapping, end_io_func, context); | |
387 | if (!op) { | |
388 | _leave(" = -ENOMEM"); | |
389 | return -ENOMEM; | |
390 | } | |
9f10523f | 391 | op->n_pages = 1; |
b5108822 DH |
392 | |
393 | spin_lock(&cookie->lock); | |
394 | ||
395 | if (hlist_empty(&cookie->backing_objects)) | |
396 | goto nobufs_unlock; | |
397 | object = hlist_entry(cookie->backing_objects.first, | |
398 | struct fscache_object, cookie_link); | |
399 | ||
400 | ASSERTCMP(object->state, >, FSCACHE_OBJECT_LOOKING_UP); | |
401 | ||
4fbf4291 | 402 | atomic_inc(&object->n_reads); |
9f10523f | 403 | __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); |
4fbf4291 | 404 | |
b5108822 | 405 | if (fscache_submit_op(object, &op->op) < 0) |
9f10523f | 406 | goto nobufs_unlock_dec; |
b5108822 DH |
407 | spin_unlock(&cookie->lock); |
408 | ||
409 | fscache_stat(&fscache_n_retrieval_ops); | |
410 | ||
411 | /* pin the netfs read context in case we need to do the actual netfs | |
412 | * read because we've encountered a cache read failure */ | |
413 | fscache_get_context(object->cookie, op->context); | |
414 | ||
415 | /* we wait for the operation to become active, and then process it | |
416 | * *here*, in this thread, and not in the thread pool */ | |
60d543ca DH |
417 | ret = fscache_wait_for_retrieval_activation( |
418 | object, op, | |
419 | __fscache_stat(&fscache_n_retrieval_op_waits), | |
420 | __fscache_stat(&fscache_n_retrievals_object_dead)); | |
421 | if (ret < 0) | |
422 | goto error; | |
b5108822 DH |
423 | |
424 | /* ask the cache to honour the operation */ | |
425 | if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) { | |
52bd75fd | 426 | fscache_stat(&fscache_n_cop_allocate_page); |
b5108822 | 427 | ret = object->cache->ops->allocate_page(op, page, gfp); |
52bd75fd | 428 | fscache_stat_d(&fscache_n_cop_allocate_page); |
b5108822 DH |
429 | if (ret == 0) |
430 | ret = -ENODATA; | |
431 | } else { | |
52bd75fd | 432 | fscache_stat(&fscache_n_cop_read_or_alloc_page); |
b5108822 | 433 | ret = object->cache->ops->read_or_alloc_page(op, page, gfp); |
52bd75fd | 434 | fscache_stat_d(&fscache_n_cop_read_or_alloc_page); |
b5108822 DH |
435 | } |
436 | ||
5753c441 | 437 | error: |
b5108822 DH |
438 | if (ret == -ENOMEM) |
439 | fscache_stat(&fscache_n_retrievals_nomem); | |
440 | else if (ret == -ERESTARTSYS) | |
441 | fscache_stat(&fscache_n_retrievals_intr); | |
442 | else if (ret == -ENODATA) | |
443 | fscache_stat(&fscache_n_retrievals_nodata); | |
444 | else if (ret < 0) | |
445 | fscache_stat(&fscache_n_retrievals_nobufs); | |
446 | else | |
447 | fscache_stat(&fscache_n_retrievals_ok); | |
448 | ||
449 | fscache_put_retrieval(op); | |
450 | _leave(" = %d", ret); | |
451 | return ret; | |
452 | ||
9f10523f DH |
453 | nobufs_unlock_dec: |
454 | atomic_dec(&object->n_reads); | |
b5108822 DH |
455 | nobufs_unlock: |
456 | spin_unlock(&cookie->lock); | |
457 | kfree(op); | |
458 | nobufs: | |
459 | fscache_stat(&fscache_n_retrievals_nobufs); | |
460 | _leave(" = -ENOBUFS"); | |
461 | return -ENOBUFS; | |
462 | } | |
463 | EXPORT_SYMBOL(__fscache_read_or_alloc_page); | |
464 | ||
465 | /* | |
466 | * read a list of page from the cache or allocate a block in which to store | |
467 | * them | |
468 | * - we return: | |
469 | * -ENOMEM - out of memory, some pages may be being read | |
470 | * -ERESTARTSYS - interrupted, some pages may be being read | |
471 | * -ENOBUFS - no backing object or space available in which to cache any | |
472 | * pages not being read | |
473 | * -ENODATA - no data available in the backing object for some or all of | |
474 | * the pages | |
475 | * 0 - dispatched a read on all pages | |
476 | * | |
477 | * end_io_func() will be called for each page read from the cache as it is | |
478 | * finishes being read | |
479 | * | |
480 | * any pages for which a read is dispatched will be removed from pages and | |
481 | * nr_pages | |
482 | */ | |
483 | int __fscache_read_or_alloc_pages(struct fscache_cookie *cookie, | |
484 | struct address_space *mapping, | |
485 | struct list_head *pages, | |
486 | unsigned *nr_pages, | |
487 | fscache_rw_complete_t end_io_func, | |
488 | void *context, | |
489 | gfp_t gfp) | |
490 | { | |
b5108822 DH |
491 | struct fscache_retrieval *op; |
492 | struct fscache_object *object; | |
493 | int ret; | |
494 | ||
495 | _enter("%p,,%d,,,", cookie, *nr_pages); | |
496 | ||
497 | fscache_stat(&fscache_n_retrievals); | |
498 | ||
499 | if (hlist_empty(&cookie->backing_objects)) | |
500 | goto nobufs; | |
501 | ||
ef778e7a DH |
502 | if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { |
503 | _leave(" = -ENOBUFS [invalidating]"); | |
504 | return -ENOBUFS; | |
505 | } | |
506 | ||
b5108822 DH |
507 | ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); |
508 | ASSERTCMP(*nr_pages, >, 0); | |
509 | ASSERT(!list_empty(pages)); | |
510 | ||
511 | if (fscache_wait_for_deferred_lookup(cookie) < 0) | |
512 | return -ERESTARTSYS; | |
513 | ||
514 | op = fscache_alloc_retrieval(mapping, end_io_func, context); | |
515 | if (!op) | |
516 | return -ENOMEM; | |
9f10523f | 517 | op->n_pages = *nr_pages; |
b5108822 DH |
518 | |
519 | spin_lock(&cookie->lock); | |
520 | ||
521 | if (hlist_empty(&cookie->backing_objects)) | |
522 | goto nobufs_unlock; | |
523 | object = hlist_entry(cookie->backing_objects.first, | |
524 | struct fscache_object, cookie_link); | |
525 | ||
4fbf4291 | 526 | atomic_inc(&object->n_reads); |
9f10523f | 527 | __set_bit(FSCACHE_OP_DEC_READ_CNT, &op->op.flags); |
4fbf4291 | 528 | |
b5108822 | 529 | if (fscache_submit_op(object, &op->op) < 0) |
9f10523f | 530 | goto nobufs_unlock_dec; |
b5108822 DH |
531 | spin_unlock(&cookie->lock); |
532 | ||
533 | fscache_stat(&fscache_n_retrieval_ops); | |
534 | ||
535 | /* pin the netfs read context in case we need to do the actual netfs | |
536 | * read because we've encountered a cache read failure */ | |
537 | fscache_get_context(object->cookie, op->context); | |
538 | ||
539 | /* we wait for the operation to become active, and then process it | |
540 | * *here*, in this thread, and not in the thread pool */ | |
60d543ca DH |
541 | ret = fscache_wait_for_retrieval_activation( |
542 | object, op, | |
543 | __fscache_stat(&fscache_n_retrieval_op_waits), | |
544 | __fscache_stat(&fscache_n_retrievals_object_dead)); | |
545 | if (ret < 0) | |
546 | goto error; | |
b5108822 DH |
547 | |
548 | /* ask the cache to honour the operation */ | |
52bd75fd DH |
549 | if (test_bit(FSCACHE_COOKIE_NO_DATA_YET, &object->cookie->flags)) { |
550 | fscache_stat(&fscache_n_cop_allocate_pages); | |
551 | ret = object->cache->ops->allocate_pages( | |
552 | op, pages, nr_pages, gfp); | |
553 | fscache_stat_d(&fscache_n_cop_allocate_pages); | |
554 | } else { | |
555 | fscache_stat(&fscache_n_cop_read_or_alloc_pages); | |
556 | ret = object->cache->ops->read_or_alloc_pages( | |
557 | op, pages, nr_pages, gfp); | |
558 | fscache_stat_d(&fscache_n_cop_read_or_alloc_pages); | |
559 | } | |
b5108822 | 560 | |
5753c441 | 561 | error: |
b5108822 DH |
562 | if (ret == -ENOMEM) |
563 | fscache_stat(&fscache_n_retrievals_nomem); | |
564 | else if (ret == -ERESTARTSYS) | |
565 | fscache_stat(&fscache_n_retrievals_intr); | |
566 | else if (ret == -ENODATA) | |
567 | fscache_stat(&fscache_n_retrievals_nodata); | |
568 | else if (ret < 0) | |
569 | fscache_stat(&fscache_n_retrievals_nobufs); | |
570 | else | |
571 | fscache_stat(&fscache_n_retrievals_ok); | |
572 | ||
573 | fscache_put_retrieval(op); | |
574 | _leave(" = %d", ret); | |
575 | return ret; | |
576 | ||
9f10523f DH |
577 | nobufs_unlock_dec: |
578 | atomic_dec(&object->n_reads); | |
b5108822 DH |
579 | nobufs_unlock: |
580 | spin_unlock(&cookie->lock); | |
581 | kfree(op); | |
582 | nobufs: | |
583 | fscache_stat(&fscache_n_retrievals_nobufs); | |
584 | _leave(" = -ENOBUFS"); | |
585 | return -ENOBUFS; | |
586 | } | |
587 | EXPORT_SYMBOL(__fscache_read_or_alloc_pages); | |
588 | ||
589 | /* | |
590 | * allocate a block in the cache on which to store a page | |
591 | * - we return: | |
592 | * -ENOMEM - out of memory, nothing done | |
593 | * -ERESTARTSYS - interrupted | |
594 | * -ENOBUFS - no backing object available in which to cache the block | |
595 | * 0 - block allocated | |
596 | */ | |
597 | int __fscache_alloc_page(struct fscache_cookie *cookie, | |
598 | struct page *page, | |
599 | gfp_t gfp) | |
600 | { | |
601 | struct fscache_retrieval *op; | |
602 | struct fscache_object *object; | |
603 | int ret; | |
604 | ||
605 | _enter("%p,%p,,,", cookie, page); | |
606 | ||
607 | fscache_stat(&fscache_n_allocs); | |
608 | ||
609 | if (hlist_empty(&cookie->backing_objects)) | |
610 | goto nobufs; | |
611 | ||
612 | ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); | |
613 | ASSERTCMP(page, !=, NULL); | |
614 | ||
ef778e7a DH |
615 | if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { |
616 | _leave(" = -ENOBUFS [invalidating]"); | |
617 | return -ENOBUFS; | |
618 | } | |
619 | ||
b5108822 DH |
620 | if (fscache_wait_for_deferred_lookup(cookie) < 0) |
621 | return -ERESTARTSYS; | |
622 | ||
623 | op = fscache_alloc_retrieval(page->mapping, NULL, NULL); | |
624 | if (!op) | |
625 | return -ENOMEM; | |
9f10523f | 626 | op->n_pages = 1; |
b5108822 DH |
627 | |
628 | spin_lock(&cookie->lock); | |
629 | ||
630 | if (hlist_empty(&cookie->backing_objects)) | |
631 | goto nobufs_unlock; | |
632 | object = hlist_entry(cookie->backing_objects.first, | |
633 | struct fscache_object, cookie_link); | |
634 | ||
635 | if (fscache_submit_op(object, &op->op) < 0) | |
636 | goto nobufs_unlock; | |
637 | spin_unlock(&cookie->lock); | |
638 | ||
639 | fscache_stat(&fscache_n_alloc_ops); | |
640 | ||
60d543ca DH |
641 | ret = fscache_wait_for_retrieval_activation( |
642 | object, op, | |
643 | __fscache_stat(&fscache_n_alloc_op_waits), | |
644 | __fscache_stat(&fscache_n_allocs_object_dead)); | |
645 | if (ret < 0) | |
646 | goto error; | |
b5108822 DH |
647 | |
648 | /* ask the cache to honour the operation */ | |
52bd75fd | 649 | fscache_stat(&fscache_n_cop_allocate_page); |
b5108822 | 650 | ret = object->cache->ops->allocate_page(op, page, gfp); |
52bd75fd | 651 | fscache_stat_d(&fscache_n_cop_allocate_page); |
b5108822 | 652 | |
5753c441 DH |
653 | error: |
654 | if (ret == -ERESTARTSYS) | |
655 | fscache_stat(&fscache_n_allocs_intr); | |
656 | else if (ret < 0) | |
b5108822 DH |
657 | fscache_stat(&fscache_n_allocs_nobufs); |
658 | else | |
659 | fscache_stat(&fscache_n_allocs_ok); | |
660 | ||
661 | fscache_put_retrieval(op); | |
662 | _leave(" = %d", ret); | |
663 | return ret; | |
664 | ||
665 | nobufs_unlock: | |
666 | spin_unlock(&cookie->lock); | |
667 | kfree(op); | |
668 | nobufs: | |
669 | fscache_stat(&fscache_n_allocs_nobufs); | |
670 | _leave(" = -ENOBUFS"); | |
671 | return -ENOBUFS; | |
672 | } | |
673 | EXPORT_SYMBOL(__fscache_alloc_page); | |
674 | ||
675 | /* | |
676 | * release a write op reference | |
677 | */ | |
678 | static void fscache_release_write_op(struct fscache_operation *_op) | |
679 | { | |
680 | _enter("{OP%x}", _op->debug_id); | |
681 | } | |
682 | ||
683 | /* | |
684 | * perform the background storage of a page into the cache | |
685 | */ | |
686 | static void fscache_write_op(struct fscache_operation *_op) | |
687 | { | |
688 | struct fscache_storage *op = | |
689 | container_of(_op, struct fscache_storage, op); | |
690 | struct fscache_object *object = op->op.object; | |
1bccf513 | 691 | struct fscache_cookie *cookie; |
b5108822 DH |
692 | struct page *page; |
693 | unsigned n; | |
694 | void *results[1]; | |
695 | int ret; | |
696 | ||
697 | _enter("{OP%x,%d}", op->op.debug_id, atomic_read(&op->op.usage)); | |
698 | ||
b5108822 | 699 | spin_lock(&object->lock); |
1bccf513 | 700 | cookie = object->cookie; |
b5108822 | 701 | |
7ef001e9 DH |
702 | if (!fscache_object_is_active(object)) { |
703 | /* If we get here, then the on-disk cache object likely longer | |
704 | * exists, so we should just cancel this write operation. | |
705 | */ | |
b5108822 | 706 | spin_unlock(&object->lock); |
7ef001e9 DH |
707 | op->op.state = FSCACHE_OP_ST_CANCELLED; |
708 | _leave(" [inactive]"); | |
709 | return; | |
710 | } | |
711 | ||
712 | if (!cookie) { | |
713 | /* If we get here, then the cookie belonging to the object was | |
714 | * detached, probably by the cookie being withdrawn due to | |
715 | * memory pressure, which means that the pages we might write | |
716 | * to the cache from no longer exist - therefore, we can just | |
717 | * cancel this write operation. | |
718 | */ | |
719 | spin_unlock(&object->lock); | |
720 | op->op.state = FSCACHE_OP_ST_CANCELLED; | |
721 | _leave(" [cancel] op{f=%lx s=%u} obj{s=%u f=%lx}", | |
722 | _op->flags, _op->state, object->state, object->flags); | |
b5108822 DH |
723 | return; |
724 | } | |
725 | ||
1bccf513 DH |
726 | spin_lock(&cookie->stores_lock); |
727 | ||
b5108822 DH |
728 | fscache_stat(&fscache_n_store_calls); |
729 | ||
730 | /* find a page to store */ | |
731 | page = NULL; | |
732 | n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, 1, | |
733 | FSCACHE_COOKIE_PENDING_TAG); | |
734 | if (n != 1) | |
735 | goto superseded; | |
736 | page = results[0]; | |
737 | _debug("gang %d [%lx]", n, page->index); | |
1bccf513 DH |
738 | if (page->index > op->store_limit) { |
739 | fscache_stat(&fscache_n_store_pages_over_limit); | |
b5108822 | 740 | goto superseded; |
1bccf513 | 741 | } |
b5108822 | 742 | |
08a66859 DC |
743 | radix_tree_tag_set(&cookie->stores, page->index, |
744 | FSCACHE_COOKIE_STORING_TAG); | |
745 | radix_tree_tag_clear(&cookie->stores, page->index, | |
746 | FSCACHE_COOKIE_PENDING_TAG); | |
b5108822 | 747 | |
1bccf513 | 748 | spin_unlock(&cookie->stores_lock); |
b5108822 | 749 | spin_unlock(&object->lock); |
b5108822 | 750 | |
08a66859 DC |
751 | fscache_stat(&fscache_n_store_pages); |
752 | fscache_stat(&fscache_n_cop_write_page); | |
753 | ret = object->cache->ops->write_page(op, page); | |
754 | fscache_stat_d(&fscache_n_cop_write_page); | |
08a66859 DC |
755 | fscache_end_page_write(object, page); |
756 | if (ret < 0) { | |
08a66859 | 757 | fscache_abort_object(object); |
9f10523f | 758 | fscache_op_complete(&op->op); |
08a66859 DC |
759 | } else { |
760 | fscache_enqueue_operation(&op->op); | |
b5108822 DH |
761 | } |
762 | ||
763 | _leave(""); | |
764 | return; | |
765 | ||
766 | superseded: | |
767 | /* this writer is going away and there aren't any more things to | |
768 | * write */ | |
769 | _debug("cease"); | |
1bccf513 | 770 | spin_unlock(&cookie->stores_lock); |
b5108822 DH |
771 | clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); |
772 | spin_unlock(&object->lock); | |
9f10523f | 773 | fscache_op_complete(&op->op); |
b5108822 DH |
774 | _leave(""); |
775 | } | |
776 | ||
ef778e7a DH |
777 | /* |
778 | * Clear the pages pending writing for invalidation | |
779 | */ | |
780 | void fscache_invalidate_writes(struct fscache_cookie *cookie) | |
781 | { | |
782 | struct page *page; | |
783 | void *results[16]; | |
784 | int n, i; | |
785 | ||
786 | _enter(""); | |
787 | ||
788 | while (spin_lock(&cookie->stores_lock), | |
789 | n = radix_tree_gang_lookup_tag(&cookie->stores, results, 0, | |
790 | ARRAY_SIZE(results), | |
791 | FSCACHE_COOKIE_PENDING_TAG), | |
792 | n > 0) { | |
793 | for (i = n - 1; i >= 0; i--) { | |
794 | page = results[i]; | |
795 | radix_tree_delete(&cookie->stores, page->index); | |
796 | } | |
797 | ||
798 | spin_unlock(&cookie->stores_lock); | |
799 | ||
800 | for (i = n - 1; i >= 0; i--) | |
801 | page_cache_release(results[i]); | |
802 | } | |
803 | ||
804 | spin_unlock(&cookie->stores_lock); | |
805 | _leave(""); | |
806 | } | |
807 | ||
b5108822 DH |
808 | /* |
809 | * request a page be stored in the cache | |
810 | * - returns: | |
811 | * -ENOMEM - out of memory, nothing done | |
812 | * -ENOBUFS - no backing object available in which to cache the page | |
813 | * 0 - dispatched a write - it'll call end_io_func() when finished | |
814 | * | |
815 | * if the cookie still has a backing object at this point, that object can be | |
816 | * in one of a few states with respect to storage processing: | |
817 | * | |
818 | * (1) negative lookup, object not yet created (FSCACHE_COOKIE_CREATING is | |
819 | * set) | |
820 | * | |
821 | * (a) no writes yet (set FSCACHE_COOKIE_PENDING_FILL and queue deferred | |
822 | * fill op) | |
823 | * | |
824 | * (b) writes deferred till post-creation (mark page for writing and | |
825 | * return immediately) | |
826 | * | |
827 | * (2) negative lookup, object created, initial fill being made from netfs | |
828 | * (FSCACHE_COOKIE_INITIAL_FILL is set) | |
829 | * | |
830 | * (a) fill point not yet reached this page (mark page for writing and | |
831 | * return) | |
832 | * | |
833 | * (b) fill point passed this page (queue op to store this page) | |
834 | * | |
835 | * (3) object extant (queue op to store this page) | |
836 | * | |
837 | * any other state is invalid | |
838 | */ | |
839 | int __fscache_write_page(struct fscache_cookie *cookie, | |
840 | struct page *page, | |
841 | gfp_t gfp) | |
842 | { | |
843 | struct fscache_storage *op; | |
844 | struct fscache_object *object; | |
845 | int ret; | |
846 | ||
847 | _enter("%p,%x,", cookie, (u32) page->flags); | |
848 | ||
849 | ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); | |
850 | ASSERT(PageFsCache(page)); | |
851 | ||
852 | fscache_stat(&fscache_n_stores); | |
853 | ||
ef778e7a DH |
854 | if (test_bit(FSCACHE_COOKIE_INVALIDATING, &cookie->flags)) { |
855 | _leave(" = -ENOBUFS [invalidating]"); | |
856 | return -ENOBUFS; | |
857 | } | |
858 | ||
5f4f9f4a | 859 | op = kzalloc(sizeof(*op), GFP_NOIO | __GFP_NOMEMALLOC | __GFP_NORETRY); |
b5108822 DH |
860 | if (!op) |
861 | goto nomem; | |
862 | ||
8af7c124 TH |
863 | fscache_operation_init(&op->op, fscache_write_op, |
864 | fscache_release_write_op); | |
865 | op->op.flags = FSCACHE_OP_ASYNC | (1 << FSCACHE_OP_WAITING); | |
b5108822 DH |
866 | |
867 | ret = radix_tree_preload(gfp & ~__GFP_HIGHMEM); | |
868 | if (ret < 0) | |
869 | goto nomem_free; | |
870 | ||
871 | ret = -ENOBUFS; | |
872 | spin_lock(&cookie->lock); | |
873 | ||
874 | if (hlist_empty(&cookie->backing_objects)) | |
875 | goto nobufs; | |
876 | object = hlist_entry(cookie->backing_objects.first, | |
877 | struct fscache_object, cookie_link); | |
878 | if (test_bit(FSCACHE_IOERROR, &object->cache->flags)) | |
879 | goto nobufs; | |
880 | ||
881 | /* add the page to the pending-storage radix tree on the backing | |
882 | * object */ | |
883 | spin_lock(&object->lock); | |
1bccf513 | 884 | spin_lock(&cookie->stores_lock); |
b5108822 DH |
885 | |
886 | _debug("store limit %llx", (unsigned long long) object->store_limit); | |
887 | ||
888 | ret = radix_tree_insert(&cookie->stores, page->index, page); | |
889 | if (ret < 0) { | |
890 | if (ret == -EEXIST) | |
891 | goto already_queued; | |
892 | _debug("insert failed %d", ret); | |
893 | goto nobufs_unlock_obj; | |
894 | } | |
895 | ||
896 | radix_tree_tag_set(&cookie->stores, page->index, | |
897 | FSCACHE_COOKIE_PENDING_TAG); | |
898 | page_cache_get(page); | |
899 | ||
900 | /* we only want one writer at a time, but we do need to queue new | |
901 | * writers after exclusive ops */ | |
902 | if (test_and_set_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags)) | |
903 | goto already_pending; | |
904 | ||
1bccf513 | 905 | spin_unlock(&cookie->stores_lock); |
b5108822 DH |
906 | spin_unlock(&object->lock); |
907 | ||
908 | op->op.debug_id = atomic_inc_return(&fscache_op_debug_id); | |
909 | op->store_limit = object->store_limit; | |
910 | ||
911 | if (fscache_submit_op(object, &op->op) < 0) | |
912 | goto submit_failed; | |
913 | ||
914 | spin_unlock(&cookie->lock); | |
915 | radix_tree_preload_end(); | |
916 | fscache_stat(&fscache_n_store_ops); | |
917 | fscache_stat(&fscache_n_stores_ok); | |
918 | ||
8af7c124 | 919 | /* the work queue now carries its own ref on the object */ |
b5108822 DH |
920 | fscache_put_operation(&op->op); |
921 | _leave(" = 0"); | |
922 | return 0; | |
923 | ||
924 | already_queued: | |
925 | fscache_stat(&fscache_n_stores_again); | |
926 | already_pending: | |
1bccf513 | 927 | spin_unlock(&cookie->stores_lock); |
b5108822 DH |
928 | spin_unlock(&object->lock); |
929 | spin_unlock(&cookie->lock); | |
930 | radix_tree_preload_end(); | |
931 | kfree(op); | |
932 | fscache_stat(&fscache_n_stores_ok); | |
933 | _leave(" = 0"); | |
934 | return 0; | |
935 | ||
936 | submit_failed: | |
1bccf513 | 937 | spin_lock(&cookie->stores_lock); |
b5108822 | 938 | radix_tree_delete(&cookie->stores, page->index); |
1bccf513 | 939 | spin_unlock(&cookie->stores_lock); |
b5108822 DH |
940 | page_cache_release(page); |
941 | ret = -ENOBUFS; | |
942 | goto nobufs; | |
943 | ||
944 | nobufs_unlock_obj: | |
1147d0f9 | 945 | spin_unlock(&cookie->stores_lock); |
b5108822 DH |
946 | spin_unlock(&object->lock); |
947 | nobufs: | |
948 | spin_unlock(&cookie->lock); | |
949 | radix_tree_preload_end(); | |
950 | kfree(op); | |
951 | fscache_stat(&fscache_n_stores_nobufs); | |
952 | _leave(" = -ENOBUFS"); | |
953 | return -ENOBUFS; | |
954 | ||
955 | nomem_free: | |
956 | kfree(op); | |
957 | nomem: | |
958 | fscache_stat(&fscache_n_stores_oom); | |
959 | _leave(" = -ENOMEM"); | |
960 | return -ENOMEM; | |
961 | } | |
962 | EXPORT_SYMBOL(__fscache_write_page); | |
963 | ||
964 | /* | |
965 | * remove a page from the cache | |
966 | */ | |
967 | void __fscache_uncache_page(struct fscache_cookie *cookie, struct page *page) | |
968 | { | |
969 | struct fscache_object *object; | |
970 | ||
971 | _enter(",%p", page); | |
972 | ||
973 | ASSERTCMP(cookie->def->type, !=, FSCACHE_COOKIE_TYPE_INDEX); | |
974 | ASSERTCMP(page, !=, NULL); | |
975 | ||
976 | fscache_stat(&fscache_n_uncaches); | |
977 | ||
978 | /* cache withdrawal may beat us to it */ | |
979 | if (!PageFsCache(page)) | |
980 | goto done; | |
981 | ||
982 | /* get the object */ | |
983 | spin_lock(&cookie->lock); | |
984 | ||
985 | if (hlist_empty(&cookie->backing_objects)) { | |
986 | ClearPageFsCache(page); | |
987 | goto done_unlock; | |
988 | } | |
989 | ||
990 | object = hlist_entry(cookie->backing_objects.first, | |
991 | struct fscache_object, cookie_link); | |
992 | ||
993 | /* there might now be stuff on disk we could read */ | |
994 | clear_bit(FSCACHE_COOKIE_NO_DATA_YET, &cookie->flags); | |
995 | ||
996 | /* only invoke the cache backend if we managed to mark the page | |
997 | * uncached here; this deals with synchronisation vs withdrawal */ | |
998 | if (TestClearPageFsCache(page) && | |
999 | object->cache->ops->uncache_page) { | |
1000 | /* the cache backend releases the cookie lock */ | |
52bd75fd | 1001 | fscache_stat(&fscache_n_cop_uncache_page); |
b5108822 | 1002 | object->cache->ops->uncache_page(object, page); |
52bd75fd | 1003 | fscache_stat_d(&fscache_n_cop_uncache_page); |
b5108822 DH |
1004 | goto done; |
1005 | } | |
1006 | ||
1007 | done_unlock: | |
1008 | spin_unlock(&cookie->lock); | |
1009 | done: | |
1010 | _leave(""); | |
1011 | } | |
1012 | EXPORT_SYMBOL(__fscache_uncache_page); | |
1013 | ||
c4d6d8db DH |
1014 | /** |
1015 | * fscache_mark_page_cached - Mark a page as being cached | |
1016 | * @op: The retrieval op pages are being marked for | |
1017 | * @page: The page to be marked | |
1018 | * | |
1019 | * Mark a netfs page as being cached. After this is called, the netfs | |
1020 | * must call fscache_uncache_page() to remove the mark. | |
1021 | */ | |
1022 | void fscache_mark_page_cached(struct fscache_retrieval *op, struct page *page) | |
1023 | { | |
1024 | struct fscache_cookie *cookie = op->op.object->cookie; | |
1025 | ||
1026 | #ifdef CONFIG_FSCACHE_STATS | |
1027 | atomic_inc(&fscache_n_marks); | |
1028 | #endif | |
1029 | ||
1030 | _debug("- mark %p{%lx}", page, page->index); | |
1031 | if (TestSetPageFsCache(page)) { | |
1032 | static bool once_only; | |
1033 | if (!once_only) { | |
1034 | once_only = true; | |
1035 | printk(KERN_WARNING "FS-Cache:" | |
1036 | " Cookie type %s marked page %lx" | |
1037 | " multiple times\n", | |
1038 | cookie->def->name, page->index); | |
1039 | } | |
1040 | } | |
1041 | ||
1042 | if (cookie->def->mark_page_cached) | |
1043 | cookie->def->mark_page_cached(cookie->netfs_data, | |
1044 | op->mapping, page); | |
1045 | } | |
1046 | EXPORT_SYMBOL(fscache_mark_page_cached); | |
1047 | ||
b5108822 DH |
1048 | /** |
1049 | * fscache_mark_pages_cached - Mark pages as being cached | |
1050 | * @op: The retrieval op pages are being marked for | |
1051 | * @pagevec: The pages to be marked | |
1052 | * | |
1053 | * Mark a bunch of netfs pages as being cached. After this is called, | |
1054 | * the netfs must call fscache_uncache_page() to remove the mark. | |
1055 | */ | |
1056 | void fscache_mark_pages_cached(struct fscache_retrieval *op, | |
1057 | struct pagevec *pagevec) | |
1058 | { | |
b5108822 DH |
1059 | unsigned long loop; |
1060 | ||
c4d6d8db DH |
1061 | for (loop = 0; loop < pagevec->nr; loop++) |
1062 | fscache_mark_page_cached(op, pagevec->pages[loop]); | |
b5108822 | 1063 | |
b5108822 DH |
1064 | pagevec_reinit(pagevec); |
1065 | } | |
1066 | EXPORT_SYMBOL(fscache_mark_pages_cached); | |
c902ce1b DH |
1067 | |
1068 | /* | |
1069 | * Uncache all the pages in an inode that are marked PG_fscache, assuming them | |
1070 | * to be associated with the given cookie. | |
1071 | */ | |
1072 | void __fscache_uncache_all_inode_pages(struct fscache_cookie *cookie, | |
1073 | struct inode *inode) | |
1074 | { | |
1075 | struct address_space *mapping = inode->i_mapping; | |
1076 | struct pagevec pvec; | |
1077 | pgoff_t next; | |
1078 | int i; | |
1079 | ||
1080 | _enter("%p,%p", cookie, inode); | |
1081 | ||
1082 | if (!mapping || mapping->nrpages == 0) { | |
1083 | _leave(" [no pages]"); | |
1084 | return; | |
1085 | } | |
1086 | ||
1087 | pagevec_init(&pvec, 0); | |
1088 | next = 0; | |
b307d465 JB |
1089 | do { |
1090 | if (!pagevec_lookup(&pvec, mapping, next, PAGEVEC_SIZE)) | |
1091 | break; | |
c902ce1b DH |
1092 | for (i = 0; i < pagevec_count(&pvec); i++) { |
1093 | struct page *page = pvec.pages[i]; | |
b307d465 | 1094 | next = page->index; |
c902ce1b DH |
1095 | if (PageFsCache(page)) { |
1096 | __fscache_wait_on_page_write(cookie, page); | |
1097 | __fscache_uncache_page(cookie, page); | |
1098 | } | |
1099 | } | |
1100 | pagevec_release(&pvec); | |
1101 | cond_resched(); | |
b307d465 | 1102 | } while (++next); |
c902ce1b DH |
1103 | |
1104 | _leave(""); | |
1105 | } | |
1106 | EXPORT_SYMBOL(__fscache_uncache_all_inode_pages); |