summaryrefslogtreecommitdiff
path: root/fs/fscache/internal.h
blob: c483863b740adee564f9df12022fa13c9848050a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Internal definitions for FS-Cache
 *
 * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

/*
 * Lock order, in the order in which multiple locks should be obtained:
 * - fscache_addremove_sem
 * - cookie->lock
 * - cookie->parent->lock
 * - cache->object_list_lock
 * - object->lock
 * - object->parent->lock
 * - cookie->stores_lock
 * - fscache_thread_lock
 *
 */

#ifdef pr_fmt
#undef pr_fmt
#endif

#define pr_fmt(fmt) "FS-Cache: " fmt

#include <linux/fscache-cache.h>
#include <trace/events/fscache.h>
#include <linux/sched.h>
#include <linux/seq_file.h>

#define FSCACHE_MIN_THREADS	4
#define FSCACHE_MAX_THREADS	32

/*
 * cache.c
 */
extern struct list_head fscache_cache_list;
extern struct rw_semaphore fscache_addremove_sem;

extern struct fscache_cache *fscache_select_cache_for_object(
	struct fscache_cookie *);

/*
 * cookie.c
 */
extern struct kmem_cache *fscache_cookie_jar;

extern void fscache_free_cookie(struct fscache_cookie *);
extern struct fscache_cookie *fscache_alloc_cookie(struct fscache_cookie *,
						   const struct fscache_cookie_def *,
						   const void *, size_t,
						   const void *, size_t,
						   void *, loff_t);
extern struct fscache_cookie *fscache_hash_cookie(struct fscache_cookie *);
extern void fscache_cookie_put(struct fscache_cookie *,
			       enum fscache_cookie_trace);

/*
 * fsdef.c
 */
extern struct fscache_cookie fscache_fsdef_index;
extern struct fscache_cookie_def fscache_fsdef_netfs_def;

/*
 * histogram.c
 */
#ifdef CONFIG_FSCACHE_HISTOGRAM
extern atomic_t fscache_obj_instantiate_histogram[HZ];
extern atomic_t fscache_objs_histogram[HZ];
extern atomic_t fscache_ops_histogram[HZ];
extern atomic_t fscache_retrieval_delay_histogram[HZ];
extern atomic_t fscache_retrieval_histogram[HZ];

static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif)
{
	unsigned long jif = jiffies - start_jif;
	if (jif >= HZ)
		jif = HZ - 1;
	atomic_inc(&histogram[jif]);
}

extern const struct seq_operations fscache_histogram_ops;

#else
#define fscache_hist(hist, start_jif) do {} while (0)
#endif

/*
 * main.c
 */
extern unsigned fscache_defer_lookup;
extern unsigned fscache_defer_create;
extern unsigned fscache_debug;
extern struct kobject *fscache_root;
extern struct workqueue_struct *fscache_object_wq;
extern struct workqueue_struct *fscache_op_wq;
DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);

static inline bool fscache_object_congested(void)
{
	return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq);
}

/*
 * object.c
 */
extern void fscache_enqueue_object(struct fscache_object *);

/*
 * object-list.c
 */
#ifdef CONFIG_FSCACHE_OBJECT_LIST
extern const struct proc_ops fscache_objlist_proc_ops;

extern void fscache_objlist_add(struct fscache_object *);
extern void fscache_objlist_remove(struct fscache_object *);
#else
#define fscache_objlist_add(object) do {} while(0)
#define fscache_objlist_remove(object) do {} while(0)
#endif

/*
 * operation.c
 */
extern int fscache_submit_exclusive_op(struct fscache_object *,
				       struct fscache_operation *);
extern int fscache_submit_op(struct fscache_object *,
			     struct fscache_operation *);
extern int fscache_cancel_op(struct fscache_operation *, bool);
extern void fscache_cancel_all_ops(struct fscache_object *);
extern void fscache_abort_object(struct fscache_object *);
extern void fscache_start_operations(struct fscache_object *);
extern void fscache_operation_gc(struct work_struct *);

/*
 * page.c
 */
extern int fscache_wait_for_deferred_lookup(struct fscache_cookie *);
extern int fscache_wait_for_operation_activation(struct fscache_object *,
						 struct fscache_operation *,
						 atomic_t *,
						 atomic_t *);
extern void fscache_invalidate_writes(struct fscache_cookie *);
struct fscache_retrieval *fscache_alloc_retrieval(struct fscache_cookie *cookie,
						  struct address_space *mapping,
						  fscache_rw_complete_t end_io_func,
						  void *context);

/*
 * proc.c
 */
#ifdef CONFIG_PROC_FS
extern int __init fscache_proc_init(void);
extern void fscache_proc_cleanup(void);
#else
#define fscache_proc_init()	(0)
#define fscache_proc_cleanup()	do {} while (0)
#endif

/*
 * stats.c
 */
#ifdef CONFIG_FSCACHE_STATS
extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];

extern atomic_t fscache_n_op_pend;
extern atomic_t fscache_n_op_run;
extern atomic_t fscache_n_op_enqueue;
extern atomic_t fscache_n_op_deferred_release;
extern atomic_t fscache_n_op_initialised;
extern atomic_t fscache_n_op_release;
extern atomic_t fscache_n_op_gc;
extern atomic_t fscache_n_op_cancelled;
extern atomic_t fscache_n_op_rejected;

extern atomic_t fscache_n_attr_changed;
extern atomic_t fscache_n_attr_changed_ok;
extern atomic_t fscache_n_attr_changed_nobufs;
extern atomic_t fscache_n_attr_changed_nomem;
extern atomic_t fscache_n_attr_changed_calls;

extern atomic_t fscache_n_allocs;
extern atomic_t fscache_n_allocs_ok;
extern atomic_t fscache_n_allocs_wait;
extern atomic_t fscache_n_allocs_nobufs;
extern atomic_t fscache_n_allocs_intr;
extern atomic_t fscache_n_allocs_object_dead;
extern atomic_t fscache_n_alloc_ops;
extern atomic_t fscache_n_alloc_op_waits;

extern atomic_t fscache_n_retrievals;
extern atomic_t fscache_n_retrievals_ok;
extern atomic_t fscache_n_retrievals_wait;
extern atomic_t fscache_n_retrievals_nodata;
extern atomic_t fscache_n_retrievals_nobufs;
extern atomic_t fscache_n_retrievals_intr;
extern atomic_t fscache_n_retrievals_nomem;
extern atomic_t fscache_n_retrievals_object_dead;
extern atomic_t fscache_n_retrieval_ops;
extern atomic_t fscache_n_retrieval_op_waits;

extern atomic_t fscache_n_stores;
extern atomic_t fscache_n_stores_ok;
extern atomic_t fscache_n_stores_again;
extern atomic_t fscache_n_stores_nobufs;
extern atomic_t fscache_n_stores_oom;
extern atomic_t fscache_n_store_ops;
extern atomic_t fscache_n_store_calls;
extern atomic_t fscache_n_store_pages;
extern atomic_t fscache_n_store_radix_deletes;
extern atomic_t fscache_n_store_pages_over_limit;

extern atomic_t fscache_n_store_vmscan_not_storing;
extern atomic_t fscache_n_store_vmscan_gone;
extern atomic_t fscache_n_store_vmscan_busy;
extern atomic_t fscache_n_store_vmscan_cancelled;
extern atomic_t fscache_n_store_vmscan_wait;

extern atomic_t fscache_n_marks;
extern atomic_t fscache_n_uncaches;

extern atomic_t fscache_n_acquires;
extern atomic_t fscache_n_acquires_null;
extern atomic_t fscache_n_acquires_no_cache;
extern atomic_t fscache_n_acquires_ok;
extern atomic_t fscache_n_acquires_nobufs;
extern atomic_t fscache_n_acquires_oom;

extern atomic_t fscache_n_invalidates;
extern atomic_t fscache_n_invalidates_run;

extern atomic_t fscache_n_updates;
extern atomic_t fscache_n_updates_null;
extern atomic_t fscache_n_updates_run;

extern atomic_t fscache_n_relinquishes;
extern atomic_t fscache_n_relinquishes_null;
extern atomic_t fscache_n_relinquishes_waitcrt;
extern atomic_t fscache_n_relinquishes_retire;

extern atomic_t fscache_n_cookie_index;
extern atomic_t fscache_n_cookie_data;
extern atomic_t fscache_n_cookie_special;

extern atomic_t fscache_n_object_alloc;
extern atomic_t fscache_n_object_no_alloc;
extern atomic_t fscache_n_object_lookups;
extern atomic_t fscache_n_object_lookups_negative;
extern atomic_t fscache_n_object_lookups_positive;
extern atomic_t fscache_n_object_lookups_timed_out;
extern atomic_t fscache_n_object_created;
extern atomic_t fscache_n_object_avail;
extern atomic_t fscache_n_object_dead;

extern atomic_t fscache_n_checkaux_none;
extern atomic_t fscache_n_checkaux_okay;
extern atomic_t fscache_n_checkaux_update;
extern atomic_t fscache_n_checkaux_obsolete;

extern atomic_t fscache_n_cop_alloc_object;
extern atomic_t fscache_n_cop_lookup_object;
extern atomic_t fscache_n_cop_lookup_complete;
extern atomic_t fscache_n_cop_grab_object;
extern atomic_t fscache_n_cop_invalidate_object;
extern atomic_t fscache_n_cop_update_object;
extern atomic_t fscache_n_cop_drop_object;
extern atomic_t fscache_n_cop_put_object;
extern atomic_t fscache_n_cop_sync_cache;
extern atomic_t fscache_n_cop_attr_changed;
extern atomic_t fscache_n_cop_read_or_alloc_page;
extern atomic_t fscache_n_cop_read_or_alloc_pages;
extern atomic_t fscache_n_cop_allocate_page;
extern atomic_t fscache_n_cop_allocate_pages;
extern atomic_t fscache_n_cop_write_page;
extern atomic_t fscache_n_cop_uncache_page;
extern atomic_t fscache_n_cop_dissociate_pages;

extern atomic_t fscache_n_cache_no_space_reject;
extern atomic_t fscache_n_cache_stale_objects;
extern atomic_t fscache_n_cache_retired_objects;
extern atomic_t fscache_n_cache_culled_objects;

static inline void fscache_stat(atomic_t *stat)
{
	atomic_inc(stat);
}

static inline void fscache_stat_d(atomic_t *stat)
{
	atomic_dec(stat);
}

#define __fscache_stat(stat) (stat)

int fscache_stats_show(struct seq_file *m, void *v);
#else

#define __fscache_stat(stat) (NULL)
#define fscache_stat(stat) do {} while (0)
#define fscache_stat_d(stat) do {} while (0)
#endif

/*
 * raise an event on an object
 * - if the event is not masked for that object, then the object is
 *   queued for attention by the thread pool.
 */
static inline void fscache_raise_event(struct fscache_object *object,
				       unsigned event)
{
	BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS);
#if 0
	printk("*** fscache_raise_event(OBJ%d{%lx},%x)\n",
	       object->debug_id, object->event_mask, (1 << event));
#endif
	if (!test_and_set_bit(event, &object->events) &&
	    test_bit(event, &object->event_mask))
		fscache_enqueue_object(object);
}

static inline void fscache_cookie_get(struct fscache_cookie *cookie,
				      enum fscache_cookie_trace where)
{
	int usage = atomic_inc_return(&cookie->usage);

	trace_fscache_cookie(cookie, where, usage);
}

/*
 * get an extra reference to a netfs retrieval context
 */
static inline
void *fscache_get_context(struct fscache_cookie *cookie, void *context)
{
	if (cookie->def->get_context)
		cookie->def->get_context(cookie->netfs_data, context);
	return context;
}

/*
 * release a reference to a netfs retrieval context
 */
static inline
void fscache_put_context(struct fscache_cookie *cookie, void *context)
{
	if (cookie->def->put_context)
		cookie->def->put_context(cookie->netfs_data, context);
}

/*
 * Update the auxiliary data on a cookie.
 */
static inline
void fscache_update_aux(struct fscache_cookie *cookie, const void *aux_data)
{
	void *p;

	if (!aux_data)
		return;
	if (cookie->aux_len <= sizeof(cookie->inline_aux))
		p = cookie->inline_aux;
	else
		p = cookie->aux;

	if (memcmp(p, aux_data, cookie->aux_len) != 0) {
		memcpy(p, aux_data, cookie->aux_len);
		set_bit(FSCACHE_COOKIE_AUX_UPDATED, &cookie->flags);
	}
}

/*****************************************************************************/
/*
 * debug tracing
 */
#define dbgprintk(FMT, ...) \
	printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)

#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)

#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)

#ifdef __KDEBUG
#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)

#elif defined(CONFIG_FSCACHE_DEBUG)
#define _enter(FMT, ...)			\
do {						\
	if (__do_kdebug(ENTER))			\
		kenter(FMT, ##__VA_ARGS__);	\
} while (0)

#define _leave(FMT, ...)			\
do {						\
	if (__do_kdebug(LEAVE))			\
		kleave(FMT, ##__VA_ARGS__);	\
} while (0)

#define _debug(FMT, ...)			\
do {						\
	if (__do_kdebug(DEBUG))			\
		kdebug(FMT, ##__VA_ARGS__);	\
} while (0)

#else
#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
#endif

/*
 * determine whether a particular optional debugging point should be logged
 * - we need to go through three steps to persuade cpp to correctly join the
 *   shorthand in FSCACHE_DEBUG_LEVEL with its prefix
 */
#define ____do_kdebug(LEVEL, POINT) \
	unlikely((fscache_debug & \
		  (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
#define ___do_kdebug(LEVEL, POINT) \
	____do_kdebug(LEVEL, POINT)
#define __do_kdebug(POINT) \
	___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)

#define FSCACHE_DEBUG_CACHE	0
#define FSCACHE_DEBUG_COOKIE	1
#define FSCACHE_DEBUG_PAGE	2
#define FSCACHE_DEBUG_OPERATION	3

#define FSCACHE_POINT_ENTER	1
#define FSCACHE_POINT_LEAVE	2
#define FSCACHE_POINT_DEBUG	4

#ifndef FSCACHE_DEBUG_LEVEL
#define FSCACHE_DEBUG_LEVEL CACHE
#endif

/*
 * assertions
 */
#if 1 /* defined(__KDEBUGALL) */

#define ASSERT(X)							\
do {									\
	if (unlikely(!(X))) {						\
		pr_err("\n");					\
		pr_err("Assertion failed\n");	\
		BUG();							\
	}								\
} while (0)

#define ASSERTCMP(X, OP, Y)						\
do {									\
	if (unlikely(!((X) OP (Y)))) {					\
		pr_err("\n");					\
		pr_err("Assertion failed\n");	\
		pr_err("%lx " #OP " %lx is false\n",		\
		       (unsigned long)(X), (unsigned long)(Y));		\
		BUG();							\
	}								\
} while (0)

#define ASSERTIF(C, X)							\
do {									\
	if (unlikely((C) && !(X))) {					\
		pr_err("\n");					\
		pr_err("Assertion failed\n");	\
		BUG();							\
	}								\
} while (0)

#define ASSERTIFCMP(C, X, OP, Y)					\
do {									\
	if (unlikely((C) && !((X) OP (Y)))) {				\
		pr_err("\n");					\
		pr_err("Assertion failed\n");	\
		pr_err("%lx " #OP " %lx is false\n",		\
		       (unsigned long)(X), (unsigned long)(Y));		\
		BUG();							\
	}								\
} while (0)

#else

#define ASSERT(X)			do {} while (0)
#define ASSERTCMP(X, OP, Y)		do {} while (0)
#define ASSERTIF(C, X)			do {} while (0)
#define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)

#endif /* assert or not */