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952efe7b DH |
1 | /* FS-Cache worker operation management routines |
2 | * | |
3 | * Copyright (C) 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 | * See Documentation/filesystems/caching/operations.txt | |
12 | */ | |
13 | ||
14 | #define FSCACHE_DEBUG_LEVEL OPERATION | |
15 | #include <linux/module.h> | |
440f0aff | 16 | #include <linux/seq_file.h> |
5a0e3ad6 | 17 | #include <linux/slab.h> |
952efe7b DH |
18 | #include "internal.h" |
19 | ||
20 | atomic_t fscache_op_debug_id; | |
21 | EXPORT_SYMBOL(fscache_op_debug_id); | |
22 | ||
1339ec98 DH |
23 | /** |
24 | * fscache_operation_init - Do basic initialisation of an operation | |
25 | * @op: The operation to initialise | |
26 | * @release: The release function to assign | |
27 | * | |
28 | * Do basic initialisation of an operation. The caller must still set flags, | |
29 | * object and processor if needed. | |
30 | */ | |
31 | void fscache_operation_init(struct fscache_operation *op, | |
32 | fscache_operation_processor_t processor, | |
33 | fscache_operation_release_t release) | |
34 | { | |
35 | INIT_WORK(&op->work, fscache_op_work_func); | |
36 | atomic_set(&op->usage, 1); | |
37 | op->state = FSCACHE_OP_ST_INITIALISED; | |
38 | op->debug_id = atomic_inc_return(&fscache_op_debug_id); | |
39 | op->processor = processor; | |
40 | op->release = release; | |
41 | INIT_LIST_HEAD(&op->pend_link); | |
03cdd0e4 | 42 | fscache_stat(&fscache_n_op_initialised); |
1339ec98 DH |
43 | } |
44 | EXPORT_SYMBOL(fscache_operation_init); | |
45 | ||
952efe7b DH |
46 | /** |
47 | * fscache_enqueue_operation - Enqueue an operation for processing | |
48 | * @op: The operation to enqueue | |
49 | * | |
50 | * Enqueue an operation for processing by the FS-Cache thread pool. | |
51 | * | |
52 | * This will get its own ref on the object. | |
53 | */ | |
54 | void fscache_enqueue_operation(struct fscache_operation *op) | |
55 | { | |
56 | _enter("{OBJ%x OP%x,%u}", | |
57 | op->object->debug_id, op->debug_id, atomic_read(&op->usage)); | |
58 | ||
5753c441 | 59 | ASSERT(list_empty(&op->pend_link)); |
952efe7b | 60 | ASSERT(op->processor != NULL); |
493f7bc1 | 61 | ASSERT(fscache_object_is_available(op->object)); |
952efe7b | 62 | ASSERTCMP(atomic_read(&op->usage), >, 0); |
9f10523f | 63 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS); |
952efe7b | 64 | |
5753c441 DH |
65 | fscache_stat(&fscache_n_op_enqueue); |
66 | switch (op->flags & FSCACHE_OP_TYPE) { | |
8af7c124 TH |
67 | case FSCACHE_OP_ASYNC: |
68 | _debug("queue async"); | |
5753c441 | 69 | atomic_inc(&op->usage); |
8af7c124 | 70 | if (!queue_work(fscache_op_wq, &op->work)) |
5753c441 DH |
71 | fscache_put_operation(op); |
72 | break; | |
5753c441 DH |
73 | case FSCACHE_OP_MYTHREAD: |
74 | _debug("queue for caller's attention"); | |
75 | break; | |
76 | default: | |
36dfd116 | 77 | pr_err("Unexpected op type %lx", op->flags); |
5753c441 DH |
78 | BUG(); |
79 | break; | |
952efe7b DH |
80 | } |
81 | } | |
82 | EXPORT_SYMBOL(fscache_enqueue_operation); | |
83 | ||
84 | /* | |
85 | * start an op running | |
86 | */ | |
87 | static void fscache_run_op(struct fscache_object *object, | |
88 | struct fscache_operation *op) | |
89 | { | |
9f10523f DH |
90 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_PENDING); |
91 | ||
92 | op->state = FSCACHE_OP_ST_IN_PROGRESS; | |
952efe7b DH |
93 | object->n_in_progress++; |
94 | if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags)) | |
95 | wake_up_bit(&op->flags, FSCACHE_OP_WAITING); | |
96 | if (op->processor) | |
97 | fscache_enqueue_operation(op); | |
98 | fscache_stat(&fscache_n_op_run); | |
99 | } | |
100 | ||
3c305984 DH |
101 | /* |
102 | * report an unexpected submission | |
103 | */ | |
104 | static void fscache_report_unexpected_submission(struct fscache_object *object, | |
105 | struct fscache_operation *op, | |
106 | const struct fscache_state *ostate) | |
107 | { | |
108 | static bool once_only; | |
109 | struct fscache_operation *p; | |
110 | unsigned n; | |
111 | ||
112 | if (once_only) | |
113 | return; | |
114 | once_only = true; | |
115 | ||
116 | kdebug("unexpected submission OP%x [OBJ%x %s]", | |
117 | op->debug_id, object->debug_id, object->state->name); | |
118 | kdebug("objstate=%s [%s]", object->state->name, ostate->name); | |
119 | kdebug("objflags=%lx", object->flags); | |
120 | kdebug("objevent=%lx [%lx]", object->events, object->event_mask); | |
121 | kdebug("ops=%u inp=%u exc=%u", | |
122 | object->n_ops, object->n_in_progress, object->n_exclusive); | |
123 | ||
124 | if (!list_empty(&object->pending_ops)) { | |
125 | n = 0; | |
126 | list_for_each_entry(p, &object->pending_ops, pend_link) { | |
127 | ASSERTCMP(p->object, ==, object); | |
128 | kdebug("%p %p", op->processor, op->release); | |
129 | n++; | |
130 | } | |
131 | ||
132 | kdebug("n=%u", n); | |
133 | } | |
134 | ||
135 | dump_stack(); | |
136 | } | |
137 | ||
952efe7b DH |
138 | /* |
139 | * submit an exclusive operation for an object | |
140 | * - other ops are excluded from running simultaneously with this one | |
141 | * - this gets any extra refs it needs on an op | |
142 | */ | |
143 | int fscache_submit_exclusive_op(struct fscache_object *object, | |
144 | struct fscache_operation *op) | |
145 | { | |
30ceec62 DH |
146 | const struct fscache_state *ostate; |
147 | unsigned long flags; | |
8d76349d DH |
148 | int ret; |
149 | ||
952efe7b DH |
150 | _enter("{OBJ%x OP%x},", object->debug_id, op->debug_id); |
151 | ||
9f10523f DH |
152 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_INITIALISED); |
153 | ASSERTCMP(atomic_read(&op->usage), >, 0); | |
154 | ||
952efe7b DH |
155 | spin_lock(&object->lock); |
156 | ASSERTCMP(object->n_ops, >=, object->n_in_progress); | |
157 | ASSERTCMP(object->n_ops, >=, object->n_exclusive); | |
5753c441 | 158 | ASSERT(list_empty(&op->pend_link)); |
952efe7b | 159 | |
30ceec62 DH |
160 | ostate = object->state; |
161 | smp_rmb(); | |
162 | ||
9f10523f | 163 | op->state = FSCACHE_OP_ST_PENDING; |
30ceec62 DH |
164 | flags = READ_ONCE(object->flags); |
165 | if (unlikely(!(flags & BIT(FSCACHE_OBJECT_IS_LIVE)))) { | |
166 | fscache_stat(&fscache_n_op_rejected); | |
167 | op->state = FSCACHE_OP_ST_CANCELLED; | |
168 | ret = -ENOBUFS; | |
169 | } else if (unlikely(fscache_cache_is_broken(object))) { | |
170 | op->state = FSCACHE_OP_ST_CANCELLED; | |
171 | ret = -EIO; | |
172 | } else if (flags & BIT(FSCACHE_OBJECT_IS_AVAILABLE)) { | |
952efe7b DH |
173 | op->object = object; |
174 | object->n_ops++; | |
175 | object->n_exclusive++; /* reads and writes must wait */ | |
176 | ||
9f10523f | 177 | if (object->n_in_progress > 0) { |
952efe7b DH |
178 | atomic_inc(&op->usage); |
179 | list_add_tail(&op->pend_link, &object->pending_ops); | |
180 | fscache_stat(&fscache_n_op_pend); | |
181 | } else if (!list_empty(&object->pending_ops)) { | |
182 | atomic_inc(&op->usage); | |
183 | list_add_tail(&op->pend_link, &object->pending_ops); | |
184 | fscache_stat(&fscache_n_op_pend); | |
185 | fscache_start_operations(object); | |
186 | } else { | |
187 | ASSERTCMP(object->n_in_progress, ==, 0); | |
188 | fscache_run_op(object, op); | |
189 | } | |
190 | ||
191 | /* need to issue a new write op after this */ | |
192 | clear_bit(FSCACHE_OBJECT_PENDING_WRITE, &object->flags); | |
8d76349d | 193 | ret = 0; |
30ceec62 | 194 | } else if (flags & BIT(FSCACHE_OBJECT_IS_LOOKED_UP)) { |
952efe7b DH |
195 | op->object = object; |
196 | object->n_ops++; | |
197 | object->n_exclusive++; /* reads and writes must wait */ | |
198 | atomic_inc(&op->usage); | |
199 | list_add_tail(&op->pend_link, &object->pending_ops); | |
200 | fscache_stat(&fscache_n_op_pend); | |
8d76349d | 201 | ret = 0; |
6515d1db DH |
202 | } else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) { |
203 | op->state = FSCACHE_OP_ST_CANCELLED; | |
204 | ret = -ENOBUFS; | |
952efe7b | 205 | } else { |
30ceec62 DH |
206 | fscache_report_unexpected_submission(object, op, ostate); |
207 | op->state = FSCACHE_OP_ST_CANCELLED; | |
208 | ret = -ENOBUFS; | |
952efe7b DH |
209 | } |
210 | ||
211 | spin_unlock(&object->lock); | |
8d76349d | 212 | return ret; |
952efe7b DH |
213 | } |
214 | ||
952efe7b DH |
215 | /* |
216 | * submit an operation for an object | |
217 | * - objects may be submitted only in the following states: | |
218 | * - during object creation (write ops may be submitted) | |
219 | * - whilst the object is active | |
220 | * - after an I/O error incurred in one of the two above states (op rejected) | |
221 | * - this gets any extra refs it needs on an op | |
222 | */ | |
223 | int fscache_submit_op(struct fscache_object *object, | |
224 | struct fscache_operation *op) | |
225 | { | |
caaef690 | 226 | const struct fscache_state *ostate; |
30ceec62 | 227 | unsigned long flags; |
952efe7b DH |
228 | int ret; |
229 | ||
230 | _enter("{OBJ%x OP%x},{%u}", | |
231 | object->debug_id, op->debug_id, atomic_read(&op->usage)); | |
232 | ||
9f10523f | 233 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_INITIALISED); |
952efe7b DH |
234 | ASSERTCMP(atomic_read(&op->usage), >, 0); |
235 | ||
236 | spin_lock(&object->lock); | |
237 | ASSERTCMP(object->n_ops, >=, object->n_in_progress); | |
238 | ASSERTCMP(object->n_ops, >=, object->n_exclusive); | |
5753c441 | 239 | ASSERT(list_empty(&op->pend_link)); |
952efe7b DH |
240 | |
241 | ostate = object->state; | |
242 | smp_rmb(); | |
243 | ||
9f10523f | 244 | op->state = FSCACHE_OP_ST_PENDING; |
30ceec62 DH |
245 | flags = READ_ONCE(object->flags); |
246 | if (unlikely(!(flags & BIT(FSCACHE_OBJECT_IS_LIVE)))) { | |
247 | fscache_stat(&fscache_n_op_rejected); | |
248 | op->state = FSCACHE_OP_ST_CANCELLED; | |
249 | ret = -ENOBUFS; | |
250 | } else if (unlikely(fscache_cache_is_broken(object))) { | |
251 | op->state = FSCACHE_OP_ST_CANCELLED; | |
252 | ret = -EIO; | |
253 | } else if (flags & BIT(FSCACHE_OBJECT_IS_AVAILABLE)) { | |
952efe7b DH |
254 | op->object = object; |
255 | object->n_ops++; | |
256 | ||
257 | if (object->n_exclusive > 0) { | |
258 | atomic_inc(&op->usage); | |
259 | list_add_tail(&op->pend_link, &object->pending_ops); | |
260 | fscache_stat(&fscache_n_op_pend); | |
261 | } else if (!list_empty(&object->pending_ops)) { | |
262 | atomic_inc(&op->usage); | |
263 | list_add_tail(&op->pend_link, &object->pending_ops); | |
264 | fscache_stat(&fscache_n_op_pend); | |
265 | fscache_start_operations(object); | |
266 | } else { | |
267 | ASSERTCMP(object->n_exclusive, ==, 0); | |
268 | fscache_run_op(object, op); | |
269 | } | |
270 | ret = 0; | |
30ceec62 | 271 | } else if (flags & BIT(FSCACHE_OBJECT_IS_LOOKED_UP)) { |
952efe7b DH |
272 | op->object = object; |
273 | object->n_ops++; | |
274 | atomic_inc(&op->usage); | |
275 | list_add_tail(&op->pend_link, &object->pending_ops); | |
276 | fscache_stat(&fscache_n_op_pend); | |
277 | ret = 0; | |
6515d1db DH |
278 | } else if (flags & BIT(FSCACHE_OBJECT_KILLED_BY_CACHE)) { |
279 | op->state = FSCACHE_OP_ST_CANCELLED; | |
280 | ret = -ENOBUFS; | |
30ceec62 | 281 | } else { |
952efe7b DH |
282 | fscache_report_unexpected_submission(object, op, ostate); |
283 | ASSERT(!fscache_object_is_active(object)); | |
9f10523f | 284 | op->state = FSCACHE_OP_ST_CANCELLED; |
952efe7b | 285 | ret = -ENOBUFS; |
952efe7b DH |
286 | } |
287 | ||
288 | spin_unlock(&object->lock); | |
289 | return ret; | |
290 | } | |
291 | ||
292 | /* | |
293 | * queue an object for withdrawal on error, aborting all following asynchronous | |
294 | * operations | |
295 | */ | |
296 | void fscache_abort_object(struct fscache_object *object) | |
297 | { | |
298 | _enter("{OBJ%x}", object->debug_id); | |
299 | ||
300 | fscache_raise_event(object, FSCACHE_OBJECT_EV_ERROR); | |
301 | } | |
302 | ||
303 | /* | |
dcfae32f DH |
304 | * Jump start the operation processing on an object. The caller must hold |
305 | * object->lock. | |
952efe7b DH |
306 | */ |
307 | void fscache_start_operations(struct fscache_object *object) | |
308 | { | |
309 | struct fscache_operation *op; | |
310 | bool stop = false; | |
311 | ||
312 | while (!list_empty(&object->pending_ops) && !stop) { | |
313 | op = list_entry(object->pending_ops.next, | |
314 | struct fscache_operation, pend_link); | |
315 | ||
316 | if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) { | |
317 | if (object->n_in_progress > 0) | |
318 | break; | |
319 | stop = true; | |
320 | } | |
321 | list_del_init(&op->pend_link); | |
5753c441 | 322 | fscache_run_op(object, op); |
952efe7b DH |
323 | |
324 | /* the pending queue was holding a ref on the object */ | |
325 | fscache_put_operation(op); | |
326 | } | |
327 | ||
328 | ASSERTCMP(object->n_in_progress, <=, object->n_ops); | |
329 | ||
330 | _debug("woke %d ops on OBJ%x", | |
331 | object->n_in_progress, object->debug_id); | |
332 | } | |
333 | ||
5753c441 DH |
334 | /* |
335 | * cancel an operation that's pending on an object | |
336 | */ | |
91c7fbbf | 337 | int fscache_cancel_op(struct fscache_operation *op, |
418b7eb9 DH |
338 | void (*do_cancel)(struct fscache_operation *), |
339 | bool cancel_in_progress_op) | |
5753c441 DH |
340 | { |
341 | struct fscache_object *object = op->object; | |
418b7eb9 | 342 | bool put = false; |
5753c441 DH |
343 | int ret; |
344 | ||
345 | _enter("OBJ%x OP%x}", op->object->debug_id, op->debug_id); | |
346 | ||
9f10523f DH |
347 | ASSERTCMP(op->state, >=, FSCACHE_OP_ST_PENDING); |
348 | ASSERTCMP(op->state, !=, FSCACHE_OP_ST_CANCELLED); | |
349 | ASSERTCMP(atomic_read(&op->usage), >, 0); | |
350 | ||
5753c441 DH |
351 | spin_lock(&object->lock); |
352 | ||
353 | ret = -EBUSY; | |
9f10523f DH |
354 | if (op->state == FSCACHE_OP_ST_PENDING) { |
355 | ASSERT(!list_empty(&op->pend_link)); | |
5753c441 | 356 | list_del_init(&op->pend_link); |
418b7eb9 DH |
357 | put = true; |
358 | fscache_stat(&fscache_n_op_cancelled); | |
359 | if (do_cancel) | |
360 | do_cancel(op); | |
361 | op->state = FSCACHE_OP_ST_CANCELLED; | |
362 | if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) | |
363 | object->n_exclusive--; | |
364 | if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags)) | |
365 | wake_up_bit(&op->flags, FSCACHE_OP_WAITING); | |
366 | ret = 0; | |
367 | } else if (op->state == FSCACHE_OP_ST_IN_PROGRESS && cancel_in_progress_op) { | |
73c04a47 DH |
368 | ASSERTCMP(object->n_in_progress, >, 0); |
369 | if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) | |
370 | object->n_exclusive--; | |
371 | object->n_in_progress--; | |
372 | if (object->n_in_progress == 0) | |
373 | fscache_start_operations(object); | |
374 | ||
418b7eb9 | 375 | fscache_stat(&fscache_n_op_cancelled); |
91c7fbbf DH |
376 | if (do_cancel) |
377 | do_cancel(op); | |
9f10523f | 378 | op->state = FSCACHE_OP_ST_CANCELLED; |
5753c441 DH |
379 | if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) |
380 | object->n_exclusive--; | |
381 | if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags)) | |
382 | wake_up_bit(&op->flags, FSCACHE_OP_WAITING); | |
5753c441 DH |
383 | ret = 0; |
384 | } | |
385 | ||
418b7eb9 DH |
386 | if (put) |
387 | fscache_put_operation(op); | |
5753c441 DH |
388 | spin_unlock(&object->lock); |
389 | _leave(" = %d", ret); | |
390 | return ret; | |
391 | } | |
392 | ||
ef778e7a DH |
393 | /* |
394 | * Cancel all pending operations on an object | |
395 | */ | |
396 | void fscache_cancel_all_ops(struct fscache_object *object) | |
397 | { | |
398 | struct fscache_operation *op; | |
399 | ||
400 | _enter("OBJ%x", object->debug_id); | |
401 | ||
402 | spin_lock(&object->lock); | |
403 | ||
404 | while (!list_empty(&object->pending_ops)) { | |
405 | op = list_entry(object->pending_ops.next, | |
406 | struct fscache_operation, pend_link); | |
407 | fscache_stat(&fscache_n_op_cancelled); | |
408 | list_del_init(&op->pend_link); | |
409 | ||
410 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_PENDING); | |
411 | op->state = FSCACHE_OP_ST_CANCELLED; | |
412 | ||
413 | if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) | |
414 | object->n_exclusive--; | |
415 | if (test_and_clear_bit(FSCACHE_OP_WAITING, &op->flags)) | |
416 | wake_up_bit(&op->flags, FSCACHE_OP_WAITING); | |
417 | fscache_put_operation(op); | |
418 | cond_resched_lock(&object->lock); | |
419 | } | |
420 | ||
421 | spin_unlock(&object->lock); | |
422 | _leave(""); | |
423 | } | |
424 | ||
9f10523f | 425 | /* |
1f372dff | 426 | * Record the completion or cancellation of an in-progress operation. |
9f10523f | 427 | */ |
1f372dff | 428 | void fscache_op_complete(struct fscache_operation *op, bool cancelled) |
9f10523f DH |
429 | { |
430 | struct fscache_object *object = op->object; | |
431 | ||
432 | _enter("OBJ%x", object->debug_id); | |
433 | ||
434 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_IN_PROGRESS); | |
435 | ASSERTCMP(object->n_in_progress, >, 0); | |
436 | ASSERTIFCMP(test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags), | |
437 | object->n_exclusive, >, 0); | |
438 | ASSERTIFCMP(test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags), | |
439 | object->n_in_progress, ==, 1); | |
440 | ||
441 | spin_lock(&object->lock); | |
442 | ||
1f372dff DH |
443 | op->state = cancelled ? |
444 | FSCACHE_OP_ST_CANCELLED : FSCACHE_OP_ST_COMPLETE; | |
9f10523f DH |
445 | |
446 | if (test_bit(FSCACHE_OP_EXCLUSIVE, &op->flags)) | |
447 | object->n_exclusive--; | |
448 | object->n_in_progress--; | |
449 | if (object->n_in_progress == 0) | |
450 | fscache_start_operations(object); | |
451 | ||
452 | spin_unlock(&object->lock); | |
453 | _leave(""); | |
454 | } | |
455 | EXPORT_SYMBOL(fscache_op_complete); | |
456 | ||
952efe7b DH |
457 | /* |
458 | * release an operation | |
459 | * - queues pending ops if this is the last in-progress op | |
460 | */ | |
461 | void fscache_put_operation(struct fscache_operation *op) | |
462 | { | |
463 | struct fscache_object *object; | |
464 | struct fscache_cache *cache; | |
465 | ||
466 | _enter("{OBJ%x OP%x,%d}", | |
467 | op->object->debug_id, op->debug_id, atomic_read(&op->usage)); | |
468 | ||
469 | ASSERTCMP(atomic_read(&op->usage), >, 0); | |
470 | ||
471 | if (!atomic_dec_and_test(&op->usage)) | |
472 | return; | |
473 | ||
474 | _debug("PUT OP"); | |
a39caadf DH |
475 | ASSERTIFCMP(op->state != FSCACHE_OP_ST_INITIALISED && |
476 | op->state != FSCACHE_OP_ST_COMPLETE, | |
9f10523f DH |
477 | op->state, ==, FSCACHE_OP_ST_CANCELLED); |
478 | op->state = FSCACHE_OP_ST_DEAD; | |
952efe7b DH |
479 | |
480 | fscache_stat(&fscache_n_op_release); | |
481 | ||
482 | if (op->release) { | |
483 | op->release(op); | |
484 | op->release = NULL; | |
485 | } | |
486 | ||
487 | object = op->object; | |
a39caadf DH |
488 | if (likely(object)) { |
489 | if (test_bit(FSCACHE_OP_DEC_READ_CNT, &op->flags)) | |
490 | atomic_dec(&object->n_reads); | |
491 | if (test_bit(FSCACHE_OP_UNUSE_COOKIE, &op->flags)) | |
492 | fscache_unuse_cookie(object); | |
493 | ||
494 | /* now... we may get called with the object spinlock held, so we | |
495 | * complete the cleanup here only if we can immediately acquire the | |
496 | * lock, and defer it otherwise */ | |
497 | if (!spin_trylock(&object->lock)) { | |
498 | _debug("defer put"); | |
499 | fscache_stat(&fscache_n_op_deferred_release); | |
500 | ||
501 | cache = object->cache; | |
502 | spin_lock(&cache->op_gc_list_lock); | |
503 | list_add_tail(&op->pend_link, &cache->op_gc_list); | |
504 | spin_unlock(&cache->op_gc_list_lock); | |
505 | schedule_work(&cache->op_gc); | |
506 | _leave(" [defer]"); | |
507 | return; | |
508 | } | |
952efe7b | 509 | |
a39caadf DH |
510 | ASSERTCMP(object->n_ops, >, 0); |
511 | object->n_ops--; | |
512 | if (object->n_ops == 0) | |
513 | fscache_raise_event(object, FSCACHE_OBJECT_EV_CLEARED); | |
952efe7b | 514 | |
a39caadf | 515 | spin_unlock(&object->lock); |
952efe7b DH |
516 | } |
517 | ||
952efe7b DH |
518 | kfree(op); |
519 | _leave(" [done]"); | |
520 | } | |
521 | EXPORT_SYMBOL(fscache_put_operation); | |
522 | ||
523 | /* | |
524 | * garbage collect operations that have had their release deferred | |
525 | */ | |
526 | void fscache_operation_gc(struct work_struct *work) | |
527 | { | |
528 | struct fscache_operation *op; | |
529 | struct fscache_object *object; | |
530 | struct fscache_cache *cache = | |
531 | container_of(work, struct fscache_cache, op_gc); | |
532 | int count = 0; | |
533 | ||
534 | _enter(""); | |
535 | ||
536 | do { | |
537 | spin_lock(&cache->op_gc_list_lock); | |
538 | if (list_empty(&cache->op_gc_list)) { | |
539 | spin_unlock(&cache->op_gc_list_lock); | |
540 | break; | |
541 | } | |
542 | ||
543 | op = list_entry(cache->op_gc_list.next, | |
544 | struct fscache_operation, pend_link); | |
545 | list_del(&op->pend_link); | |
546 | spin_unlock(&cache->op_gc_list_lock); | |
547 | ||
548 | object = op->object; | |
9f10523f | 549 | spin_lock(&object->lock); |
952efe7b DH |
550 | |
551 | _debug("GC DEFERRED REL OBJ%x OP%x", | |
552 | object->debug_id, op->debug_id); | |
553 | fscache_stat(&fscache_n_op_gc); | |
554 | ||
555 | ASSERTCMP(atomic_read(&op->usage), ==, 0); | |
9f10523f | 556 | ASSERTCMP(op->state, ==, FSCACHE_OP_ST_DEAD); |
952efe7b DH |
557 | |
558 | ASSERTCMP(object->n_ops, >, 0); | |
559 | object->n_ops--; | |
560 | if (object->n_ops == 0) | |
561 | fscache_raise_event(object, FSCACHE_OBJECT_EV_CLEARED); | |
562 | ||
563 | spin_unlock(&object->lock); | |
9f10523f | 564 | kfree(op); |
952efe7b DH |
565 | |
566 | } while (count++ < 20); | |
567 | ||
568 | if (!list_empty(&cache->op_gc_list)) | |
569 | schedule_work(&cache->op_gc); | |
570 | ||
571 | _leave(""); | |
572 | } | |
573 | ||
574 | /* | |
8af7c124 TH |
575 | * execute an operation using fs_op_wq to provide processing context - |
576 | * the caller holds a ref to this object, so we don't need to hold one | |
952efe7b | 577 | */ |
8af7c124 | 578 | void fscache_op_work_func(struct work_struct *work) |
952efe7b DH |
579 | { |
580 | struct fscache_operation *op = | |
8af7c124 | 581 | container_of(work, struct fscache_operation, work); |
952efe7b DH |
582 | unsigned long start; |
583 | ||
584 | _enter("{OBJ%x OP%x,%d}", | |
585 | op->object->debug_id, op->debug_id, atomic_read(&op->usage)); | |
586 | ||
587 | ASSERT(op->processor != NULL); | |
588 | start = jiffies; | |
589 | op->processor(op); | |
590 | fscache_hist(fscache_ops_histogram, start); | |
8af7c124 | 591 | fscache_put_operation(op); |
952efe7b DH |
592 | |
593 | _leave(""); | |
594 | } |