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18#ifndef _LINUX_FSCACHE_CACHE_H
19#define _LINUX_FSCACHE_CACHE_H
20
21#include <linux/fscache.h>
22#include <linux/sched.h>
23#include <linux/workqueue.h>
24
25#define NR_MAXCACHES BITS_PER_LONG
26
27struct fscache_cache;
28struct fscache_cache_ops;
29struct fscache_object;
30struct fscache_operation;
31
32
33
34
35struct fscache_cache_tag {
36 struct list_head link;
37 struct fscache_cache *cache;
38 unsigned long flags;
39#define FSCACHE_TAG_RESERVED 0
40 atomic_t usage;
41 char name[0];
42};
43
44
45
46
47struct fscache_cache {
48 const struct fscache_cache_ops *ops;
49 struct fscache_cache_tag *tag;
50 struct kobject *kobj;
51 struct list_head link;
52 size_t max_index_size;
53 char identifier[36];
54
55
56 struct work_struct op_gc;
57 struct list_head object_list;
58 struct list_head op_gc_list;
59 spinlock_t object_list_lock;
60 spinlock_t op_gc_list_lock;
61 atomic_t object_count;
62 struct fscache_object *fsdef;
63 unsigned long flags;
64#define FSCACHE_IOERROR 0
65#define FSCACHE_CACHE_WITHDRAWN 1
66};
67
68extern wait_queue_head_t fscache_cache_cleared_wq;
69
70
71
72
73
74
75typedef void (*fscache_operation_release_t)(struct fscache_operation *op);
76typedef void (*fscache_operation_processor_t)(struct fscache_operation *op);
77
78struct fscache_operation {
79 struct work_struct work;
80 struct list_head pend_link;
81 struct fscache_object *object;
82
83 unsigned long flags;
84#define FSCACHE_OP_TYPE 0x000f
85#define FSCACHE_OP_ASYNC 0x0001
86#define FSCACHE_OP_MYTHREAD 0x0002
87#define FSCACHE_OP_WAITING 4
88#define FSCACHE_OP_EXCLUSIVE 5
89#define FSCACHE_OP_DEAD 6
90#define FSCACHE_OP_DEC_READ_CNT 7
91#define FSCACHE_OP_KEEP_FLAGS 0xc0
92
93 atomic_t usage;
94 unsigned debug_id;
95
96
97
98
99 fscache_operation_processor_t processor;
100
101
102 fscache_operation_release_t release;
103
104#ifdef CONFIG_WORKQUEUE_DEBUGFS
105 struct work_struct put_work;
106 const char *name;
107 const char *state;
108#define fscache_set_op_name(OP, N) do { (OP)->name = (N); } while(0)
109#define fscache_set_op_state(OP, S) do { (OP)->state = (S); } while(0)
110#else
111#define fscache_set_op_name(OP, N) do { } while(0)
112#define fscache_set_op_state(OP, S) do { } while(0)
113#endif
114};
115
116extern atomic_t fscache_op_debug_id;
117extern void fscache_op_work_func(struct work_struct *work);
118
119extern void fscache_enqueue_operation(struct fscache_operation *);
120extern void fscache_put_operation(struct fscache_operation *);
121
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127
128
129
130static inline void fscache_operation_init(struct fscache_operation *op,
131 fscache_operation_processor_t processor,
132 fscache_operation_release_t release)
133{
134 INIT_WORK(&op->work, fscache_op_work_func);
135 atomic_set(&op->usage, 1);
136 op->debug_id = atomic_inc_return(&fscache_op_debug_id);
137 op->processor = processor;
138 op->release = release;
139 INIT_LIST_HEAD(&op->pend_link);
140 fscache_set_op_state(op, "Init");
141}
142
143
144
145
146struct fscache_retrieval {
147 struct fscache_operation op;
148 struct address_space *mapping;
149 fscache_rw_complete_t end_io_func;
150 void *context;
151 struct list_head to_do;
152 unsigned long start_time;
153};
154
155typedef int (*fscache_page_retrieval_func_t)(struct fscache_retrieval *op,
156 struct page *page,
157 gfp_t gfp);
158
159typedef int (*fscache_pages_retrieval_func_t)(struct fscache_retrieval *op,
160 struct list_head *pages,
161 unsigned *nr_pages,
162 gfp_t gfp);
163
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168
169
170static inline
171struct fscache_retrieval *fscache_get_retrieval(struct fscache_retrieval *op)
172{
173 atomic_inc(&op->op.usage);
174 return op;
175}
176
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181
182
183static inline void fscache_enqueue_retrieval(struct fscache_retrieval *op)
184{
185 fscache_enqueue_operation(&op->op);
186}
187
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193
194static inline void fscache_put_retrieval(struct fscache_retrieval *op)
195{
196 fscache_put_operation(&op->op);
197}
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205
206struct fscache_storage {
207 struct fscache_operation op;
208 pgoff_t store_limit;
209};
210
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213
214struct fscache_cache_ops {
215
216 const char *name;
217
218
219 struct fscache_object *(*alloc_object)(struct fscache_cache *cache,
220 struct fscache_cookie *cookie);
221
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223
224
225 int (*lookup_object)(struct fscache_object *object);
226
227
228 void (*lookup_complete)(struct fscache_object *object);
229
230
231 struct fscache_object *(*grab_object)(struct fscache_object *object);
232
233
234 int (*pin_object)(struct fscache_object *object);
235
236
237 void (*unpin_object)(struct fscache_object *object);
238
239
240 void (*update_object)(struct fscache_object *object);
241
242
243
244 void (*drop_object)(struct fscache_object *object);
245
246
247 void (*put_object)(struct fscache_object *object);
248
249
250 void (*sync_cache)(struct fscache_cache *cache);
251
252
253
254 int (*attr_changed)(struct fscache_object *object);
255
256
257 int (*reserve_space)(struct fscache_object *object, loff_t i_size);
258
259
260
261 fscache_page_retrieval_func_t read_or_alloc_page;
262
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264
265 fscache_pages_retrieval_func_t read_or_alloc_pages;
266
267
268
269 fscache_page_retrieval_func_t allocate_page;
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272
273 fscache_pages_retrieval_func_t allocate_pages;
274
275
276 int (*write_page)(struct fscache_storage *op, struct page *page);
277
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281
282 void (*uncache_page)(struct fscache_object *object,
283 struct page *page);
284
285
286 void (*dissociate_pages)(struct fscache_cache *cache);
287};
288
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295
296struct fscache_cookie {
297 atomic_t usage;
298 atomic_t n_children;
299 spinlock_t lock;
300 spinlock_t stores_lock;
301 struct hlist_head backing_objects;
302 const struct fscache_cookie_def *def;
303 struct fscache_cookie *parent;
304 void *netfs_data;
305 struct radix_tree_root stores;
306#define FSCACHE_COOKIE_PENDING_TAG 0
307#define FSCACHE_COOKIE_STORING_TAG 1
308
309 unsigned long flags;
310#define FSCACHE_COOKIE_LOOKING_UP 0
311#define FSCACHE_COOKIE_CREATING 1
312#define FSCACHE_COOKIE_NO_DATA_YET 2
313#define FSCACHE_COOKIE_PENDING_FILL 3
314#define FSCACHE_COOKIE_FILLING 4
315#define FSCACHE_COOKIE_UNAVAILABLE 5
316};
317
318extern struct fscache_cookie fscache_fsdef_index;
319
320
321
322
323struct fscache_object {
324 enum fscache_object_state {
325 FSCACHE_OBJECT_INIT,
326 FSCACHE_OBJECT_LOOKING_UP,
327 FSCACHE_OBJECT_CREATING,
328
329
330 FSCACHE_OBJECT_AVAILABLE,
331 FSCACHE_OBJECT_ACTIVE,
332 FSCACHE_OBJECT_UPDATING,
333
334
335 FSCACHE_OBJECT_DYING,
336 FSCACHE_OBJECT_LC_DYING,
337 FSCACHE_OBJECT_ABORT_INIT,
338 FSCACHE_OBJECT_RELEASING,
339 FSCACHE_OBJECT_RECYCLING,
340 FSCACHE_OBJECT_WITHDRAWING,
341 FSCACHE_OBJECT_DEAD,
342 FSCACHE_OBJECT__NSTATES
343 } state;
344
345 int debug_id;
346 int n_children;
347 int n_ops;
348 int n_obj_ops;
349 int n_in_progress;
350 int n_exclusive;
351 atomic_t n_reads;
352 spinlock_t lock;
353
354 unsigned long lookup_jif;
355 unsigned long event_mask;
356 unsigned long events;
357
358#define FSCACHE_OBJECT_EV_REQUEUE 0
359#define FSCACHE_OBJECT_EV_UPDATE 1
360#define FSCACHE_OBJECT_EV_CLEARED 2
361#define FSCACHE_OBJECT_EV_ERROR 3
362#define FSCACHE_OBJECT_EV_RELEASE 4
363#define FSCACHE_OBJECT_EV_RETIRE 5
364#define FSCACHE_OBJECT_EV_WITHDRAW 6
365#define FSCACHE_OBJECT_EVENTS_MASK 0x7f
366
367 unsigned long flags;
368#define FSCACHE_OBJECT_LOCK 0
369#define FSCACHE_OBJECT_PENDING_WRITE 1
370#define FSCACHE_OBJECT_WAITING 2
371
372 struct list_head cache_link;
373 struct hlist_node cookie_link;
374 struct fscache_cache *cache;
375 struct fscache_cookie *cookie;
376 struct fscache_object *parent;
377 struct work_struct work;
378 struct list_head dependents;
379 struct list_head dep_link;
380 struct list_head pending_ops;
381#ifdef CONFIG_FSCACHE_OBJECT_LIST
382 struct rb_node objlist_link;
383#endif
384 pgoff_t store_limit;
385 loff_t store_limit_l;
386};
387
388extern const char *fscache_object_states[];
389
390#define fscache_object_is_active(obj) \
391 (!test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) && \
392 (obj)->state >= FSCACHE_OBJECT_AVAILABLE && \
393 (obj)->state < FSCACHE_OBJECT_DYING)
394
395#define fscache_object_is_dead(obj) \
396 (test_bit(FSCACHE_IOERROR, &(obj)->cache->flags) && \
397 (obj)->state >= FSCACHE_OBJECT_DYING)
398
399extern void fscache_object_work_func(struct work_struct *work);
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409
410static inline
411void fscache_object_init(struct fscache_object *object,
412 struct fscache_cookie *cookie,
413 struct fscache_cache *cache)
414{
415 atomic_inc(&cache->object_count);
416
417 object->state = FSCACHE_OBJECT_INIT;
418 spin_lock_init(&object->lock);
419 INIT_LIST_HEAD(&object->cache_link);
420 INIT_HLIST_NODE(&object->cookie_link);
421 INIT_WORK(&object->work, fscache_object_work_func);
422 INIT_LIST_HEAD(&object->dependents);
423 INIT_LIST_HEAD(&object->dep_link);
424 INIT_LIST_HEAD(&object->pending_ops);
425 object->n_children = 0;
426 object->n_ops = object->n_in_progress = object->n_exclusive = 0;
427 object->events = object->event_mask = 0;
428 object->flags = 0;
429 object->store_limit = 0;
430 object->store_limit_l = 0;
431 object->cache = cache;
432 object->cookie = cookie;
433 object->parent = NULL;
434}
435
436extern void fscache_object_lookup_negative(struct fscache_object *object);
437extern void fscache_obtained_object(struct fscache_object *object);
438
439#ifdef CONFIG_FSCACHE_OBJECT_LIST
440extern void fscache_object_destroy(struct fscache_object *object);
441#else
442#define fscache_object_destroy(object) do {} while(0)
443#endif
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448
449
450
451static inline void fscache_object_destroyed(struct fscache_cache *cache)
452{
453 if (atomic_dec_and_test(&cache->object_count))
454 wake_up_all(&fscache_cache_cleared_wq);
455}
456
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462
463
464static inline void fscache_object_lookup_error(struct fscache_object *object)
465{
466 set_bit(FSCACHE_OBJECT_EV_ERROR, &object->events);
467}
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478
479
480static inline
481void fscache_set_store_limit(struct fscache_object *object, loff_t i_size)
482{
483 object->store_limit_l = i_size;
484 object->store_limit = i_size >> PAGE_SHIFT;
485 if (i_size & ~PAGE_MASK)
486 object->store_limit++;
487}
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497
498static inline void fscache_end_io(struct fscache_retrieval *op,
499 struct page *page, int error)
500{
501 op->end_io_func(page, op->context, error);
502}
503
504
505
506
507extern void fscache_init_cache(struct fscache_cache *cache,
508 const struct fscache_cache_ops *ops,
509 const char *idfmt,
510 ...) __attribute__ ((format (printf, 3, 4)));
511
512extern int fscache_add_cache(struct fscache_cache *cache,
513 struct fscache_object *fsdef,
514 const char *tagname);
515extern void fscache_withdraw_cache(struct fscache_cache *cache);
516
517extern void fscache_io_error(struct fscache_cache *cache);
518
519extern void fscache_mark_pages_cached(struct fscache_retrieval *op,
520 struct pagevec *pagevec);
521
522extern bool fscache_object_sleep_till_congested(signed long *timeoutp);
523
524extern enum fscache_checkaux fscache_check_aux(struct fscache_object *object,
525 const void *data,
526 uint16_t datalen);
527
528#endif
529