1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* Internal definitions for FS-Cache
3 *
4 * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
5 * Written by David Howells (dhowells@redhat.com)
6 */
7
8 /*
9 * Lock order, in the order in which multiple locks should be obtained:
10 * - fscache_addremove_sem
11 * - cookie->lock
12 * - cookie->parent->lock
13 * - cache->object_list_lock
14 * - object->lock
15 * - object->parent->lock
16 * - cookie->stores_lock
17 * - fscache_thread_lock
18 *
19 */
20
21 #ifdef pr_fmt
22 #undef pr_fmt
23 #endif
24
25 #define pr_fmt(fmt) "FS-Cache: " fmt
26
27 #include <linux/fscache-cache.h>
28 #include <trace/events/fscache.h>
29 #include <linux/sched.h>
30 #include <linux/seq_file.h>
31
32 #define FSCACHE_MIN_THREADS 4
33 #define FSCACHE_MAX_THREADS 32
34
35 /*
36 * cache.c
37 */
38 extern struct list_head fscache_cache_list;
39 extern struct rw_semaphore fscache_addremove_sem;
40
41 extern struct fscache_cache *fscache_select_cache_for_object(
42 struct fscache_cookie *);
43
44 /*
45 * cookie.c
46 */
47 extern struct kmem_cache *fscache_cookie_jar;
48
49 extern void fscache_free_cookie(struct fscache_cookie *);
50 extern struct fscache_cookie *fscache_alloc_cookie(struct fscache_cookie *,
51 const struct fscache_cookie_def *,
52 const void *, size_t,
53 const void *, size_t,
54 void *, loff_t);
55 extern struct fscache_cookie *fscache_hash_cookie(struct fscache_cookie *);
56 extern void fscache_cookie_put(struct fscache_cookie *,
57 enum fscache_cookie_trace);
58
59 /*
60 * fsdef.c
61 */
62 extern struct fscache_cookie fscache_fsdef_index;
63 extern struct fscache_cookie_def fscache_fsdef_netfs_def;
64
65 /*
66 * histogram.c
67 */
68 #ifdef CONFIG_FSCACHE_HISTOGRAM
69 extern atomic_t fscache_obj_instantiate_histogram[HZ];
70 extern atomic_t fscache_objs_histogram[HZ];
71 extern atomic_t fscache_ops_histogram[HZ];
72 extern atomic_t fscache_retrieval_delay_histogram[HZ];
73 extern atomic_t fscache_retrieval_histogram[HZ];
74
fscache_hist(atomic_t histogram[],unsigned long start_jif)75 static inline void fscache_hist(atomic_t histogram[], unsigned long start_jif)
76 {
77 unsigned long jif = jiffies - start_jif;
78 if (jif >= HZ)
79 jif = HZ - 1;
80 atomic_inc(&histogram[jif]);
81 }
82
83 extern const struct seq_operations fscache_histogram_ops;
84
85 #else
86 #define fscache_hist(hist, start_jif) do {} while (0)
87 #endif
88
89 /*
90 * main.c
91 */
92 extern unsigned fscache_defer_lookup;
93 extern unsigned fscache_defer_create;
94 extern unsigned fscache_debug;
95 extern struct kobject *fscache_root;
96 extern struct workqueue_struct *fscache_object_wq;
97 extern struct workqueue_struct *fscache_op_wq;
98 DECLARE_PER_CPU(wait_queue_head_t, fscache_object_cong_wait);
99
fscache_object_congested(void)100 static inline bool fscache_object_congested(void)
101 {
102 return workqueue_congested(WORK_CPU_UNBOUND, fscache_object_wq);
103 }
104
105 /*
106 * object.c
107 */
108 extern void fscache_enqueue_object(struct fscache_object *);
109
110 /*
111 * object-list.c
112 */
113 #ifdef CONFIG_FSCACHE_OBJECT_LIST
114 extern const struct file_operations fscache_objlist_fops;
115
116 extern void fscache_objlist_add(struct fscache_object *);
117 extern void fscache_objlist_remove(struct fscache_object *);
118 #else
119 #define fscache_objlist_add(object) do {} while(0)
120 #define fscache_objlist_remove(object) do {} while(0)
121 #endif
122
123 /*
124 * operation.c
125 */
126 extern int fscache_submit_exclusive_op(struct fscache_object *,
127 struct fscache_operation *);
128 extern int fscache_submit_op(struct fscache_object *,
129 struct fscache_operation *);
130 extern int fscache_cancel_op(struct fscache_operation *, bool);
131 extern void fscache_cancel_all_ops(struct fscache_object *);
132 extern void fscache_abort_object(struct fscache_object *);
133 extern void fscache_start_operations(struct fscache_object *);
134 extern void fscache_operation_gc(struct work_struct *);
135
136 /*
137 * page.c
138 */
139 extern int fscache_wait_for_deferred_lookup(struct fscache_cookie *);
140 extern int fscache_wait_for_operation_activation(struct fscache_object *,
141 struct fscache_operation *,
142 atomic_t *,
143 atomic_t *);
144 extern void fscache_invalidate_writes(struct fscache_cookie *);
145
146 /*
147 * proc.c
148 */
149 #ifdef CONFIG_PROC_FS
150 extern int __init fscache_proc_init(void);
151 extern void fscache_proc_cleanup(void);
152 #else
153 #define fscache_proc_init() (0)
154 #define fscache_proc_cleanup() do {} while (0)
155 #endif
156
157 /*
158 * stats.c
159 */
160 #ifdef CONFIG_FSCACHE_STATS
161 extern atomic_t fscache_n_ops_processed[FSCACHE_MAX_THREADS];
162 extern atomic_t fscache_n_objs_processed[FSCACHE_MAX_THREADS];
163
164 extern atomic_t fscache_n_op_pend;
165 extern atomic_t fscache_n_op_run;
166 extern atomic_t fscache_n_op_enqueue;
167 extern atomic_t fscache_n_op_deferred_release;
168 extern atomic_t fscache_n_op_initialised;
169 extern atomic_t fscache_n_op_release;
170 extern atomic_t fscache_n_op_gc;
171 extern atomic_t fscache_n_op_cancelled;
172 extern atomic_t fscache_n_op_rejected;
173
174 extern atomic_t fscache_n_attr_changed;
175 extern atomic_t fscache_n_attr_changed_ok;
176 extern atomic_t fscache_n_attr_changed_nobufs;
177 extern atomic_t fscache_n_attr_changed_nomem;
178 extern atomic_t fscache_n_attr_changed_calls;
179
180 extern atomic_t fscache_n_allocs;
181 extern atomic_t fscache_n_allocs_ok;
182 extern atomic_t fscache_n_allocs_wait;
183 extern atomic_t fscache_n_allocs_nobufs;
184 extern atomic_t fscache_n_allocs_intr;
185 extern atomic_t fscache_n_allocs_object_dead;
186 extern atomic_t fscache_n_alloc_ops;
187 extern atomic_t fscache_n_alloc_op_waits;
188
189 extern atomic_t fscache_n_retrievals;
190 extern atomic_t fscache_n_retrievals_ok;
191 extern atomic_t fscache_n_retrievals_wait;
192 extern atomic_t fscache_n_retrievals_nodata;
193 extern atomic_t fscache_n_retrievals_nobufs;
194 extern atomic_t fscache_n_retrievals_intr;
195 extern atomic_t fscache_n_retrievals_nomem;
196 extern atomic_t fscache_n_retrievals_object_dead;
197 extern atomic_t fscache_n_retrieval_ops;
198 extern atomic_t fscache_n_retrieval_op_waits;
199
200 extern atomic_t fscache_n_stores;
201 extern atomic_t fscache_n_stores_ok;
202 extern atomic_t fscache_n_stores_again;
203 extern atomic_t fscache_n_stores_nobufs;
204 extern atomic_t fscache_n_stores_oom;
205 extern atomic_t fscache_n_store_ops;
206 extern atomic_t fscache_n_store_calls;
207 extern atomic_t fscache_n_store_pages;
208 extern atomic_t fscache_n_store_radix_deletes;
209 extern atomic_t fscache_n_store_pages_over_limit;
210
211 extern atomic_t fscache_n_store_vmscan_not_storing;
212 extern atomic_t fscache_n_store_vmscan_gone;
213 extern atomic_t fscache_n_store_vmscan_busy;
214 extern atomic_t fscache_n_store_vmscan_cancelled;
215 extern atomic_t fscache_n_store_vmscan_wait;
216
217 extern atomic_t fscache_n_marks;
218 extern atomic_t fscache_n_uncaches;
219
220 extern atomic_t fscache_n_acquires;
221 extern atomic_t fscache_n_acquires_null;
222 extern atomic_t fscache_n_acquires_no_cache;
223 extern atomic_t fscache_n_acquires_ok;
224 extern atomic_t fscache_n_acquires_nobufs;
225 extern atomic_t fscache_n_acquires_oom;
226
227 extern atomic_t fscache_n_invalidates;
228 extern atomic_t fscache_n_invalidates_run;
229
230 extern atomic_t fscache_n_updates;
231 extern atomic_t fscache_n_updates_null;
232 extern atomic_t fscache_n_updates_run;
233
234 extern atomic_t fscache_n_relinquishes;
235 extern atomic_t fscache_n_relinquishes_null;
236 extern atomic_t fscache_n_relinquishes_waitcrt;
237 extern atomic_t fscache_n_relinquishes_retire;
238
239 extern atomic_t fscache_n_cookie_index;
240 extern atomic_t fscache_n_cookie_data;
241 extern atomic_t fscache_n_cookie_special;
242
243 extern atomic_t fscache_n_object_alloc;
244 extern atomic_t fscache_n_object_no_alloc;
245 extern atomic_t fscache_n_object_lookups;
246 extern atomic_t fscache_n_object_lookups_negative;
247 extern atomic_t fscache_n_object_lookups_positive;
248 extern atomic_t fscache_n_object_lookups_timed_out;
249 extern atomic_t fscache_n_object_created;
250 extern atomic_t fscache_n_object_avail;
251 extern atomic_t fscache_n_object_dead;
252
253 extern atomic_t fscache_n_checkaux_none;
254 extern atomic_t fscache_n_checkaux_okay;
255 extern atomic_t fscache_n_checkaux_update;
256 extern atomic_t fscache_n_checkaux_obsolete;
257
258 extern atomic_t fscache_n_cop_alloc_object;
259 extern atomic_t fscache_n_cop_lookup_object;
260 extern atomic_t fscache_n_cop_lookup_complete;
261 extern atomic_t fscache_n_cop_grab_object;
262 extern atomic_t fscache_n_cop_invalidate_object;
263 extern atomic_t fscache_n_cop_update_object;
264 extern atomic_t fscache_n_cop_drop_object;
265 extern atomic_t fscache_n_cop_put_object;
266 extern atomic_t fscache_n_cop_sync_cache;
267 extern atomic_t fscache_n_cop_attr_changed;
268 extern atomic_t fscache_n_cop_read_or_alloc_page;
269 extern atomic_t fscache_n_cop_read_or_alloc_pages;
270 extern atomic_t fscache_n_cop_allocate_page;
271 extern atomic_t fscache_n_cop_allocate_pages;
272 extern atomic_t fscache_n_cop_write_page;
273 extern atomic_t fscache_n_cop_uncache_page;
274 extern atomic_t fscache_n_cop_dissociate_pages;
275
276 extern atomic_t fscache_n_cache_no_space_reject;
277 extern atomic_t fscache_n_cache_stale_objects;
278 extern atomic_t fscache_n_cache_retired_objects;
279 extern atomic_t fscache_n_cache_culled_objects;
280
fscache_stat(atomic_t * stat)281 static inline void fscache_stat(atomic_t *stat)
282 {
283 atomic_inc(stat);
284 }
285
fscache_stat_d(atomic_t * stat)286 static inline void fscache_stat_d(atomic_t *stat)
287 {
288 atomic_dec(stat);
289 }
290
291 #define __fscache_stat(stat) (stat)
292
293 int fscache_stats_show(struct seq_file *m, void *v);
294 #else
295
296 #define __fscache_stat(stat) (NULL)
297 #define fscache_stat(stat) do {} while (0)
298 #define fscache_stat_d(stat) do {} while (0)
299 #endif
300
301 /*
302 * raise an event on an object
303 * - if the event is not masked for that object, then the object is
304 * queued for attention by the thread pool.
305 */
fscache_raise_event(struct fscache_object * object,unsigned event)306 static inline void fscache_raise_event(struct fscache_object *object,
307 unsigned event)
308 {
309 BUG_ON(event >= NR_FSCACHE_OBJECT_EVENTS);
310 #if 0
311 printk("*** fscache_raise_event(OBJ%d{%lx},%x)\n",
312 object->debug_id, object->event_mask, (1 << event));
313 #endif
314 if (!test_and_set_bit(event, &object->events) &&
315 test_bit(event, &object->event_mask))
316 fscache_enqueue_object(object);
317 }
318
fscache_cookie_get(struct fscache_cookie * cookie,enum fscache_cookie_trace where)319 static inline void fscache_cookie_get(struct fscache_cookie *cookie,
320 enum fscache_cookie_trace where)
321 {
322 int usage = atomic_inc_return(&cookie->usage);
323
324 trace_fscache_cookie(cookie, where, usage);
325 }
326
327 /*
328 * get an extra reference to a netfs retrieval context
329 */
330 static inline
fscache_get_context(struct fscache_cookie * cookie,void * context)331 void *fscache_get_context(struct fscache_cookie *cookie, void *context)
332 {
333 if (cookie->def->get_context)
334 cookie->def->get_context(cookie->netfs_data, context);
335 return context;
336 }
337
338 /*
339 * release a reference to a netfs retrieval context
340 */
341 static inline
fscache_put_context(struct fscache_cookie * cookie,void * context)342 void fscache_put_context(struct fscache_cookie *cookie, void *context)
343 {
344 if (cookie->def->put_context)
345 cookie->def->put_context(cookie->netfs_data, context);
346 }
347
348 /*
349 * Update the auxiliary data on a cookie.
350 */
351 static inline
fscache_update_aux(struct fscache_cookie * cookie,const void * aux_data)352 void fscache_update_aux(struct fscache_cookie *cookie, const void *aux_data)
353 {
354 void *p;
355
356 if (!aux_data)
357 return;
358 if (cookie->aux_len <= sizeof(cookie->inline_aux))
359 p = cookie->inline_aux;
360 else
361 p = cookie->aux;
362
363 if (memcmp(p, aux_data, cookie->aux_len) != 0) {
364 memcpy(p, aux_data, cookie->aux_len);
365 set_bit(FSCACHE_COOKIE_AUX_UPDATED, &cookie->flags);
366 }
367 }
368
369 /*****************************************************************************/
370 /*
371 * debug tracing
372 */
373 #define dbgprintk(FMT, ...) \
374 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
375
376 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
377 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
378 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
379
380 #define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
381
382 #ifdef __KDEBUG
383 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
384 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
385 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
386
387 #elif defined(CONFIG_FSCACHE_DEBUG)
388 #define _enter(FMT, ...) \
389 do { \
390 if (__do_kdebug(ENTER)) \
391 kenter(FMT, ##__VA_ARGS__); \
392 } while (0)
393
394 #define _leave(FMT, ...) \
395 do { \
396 if (__do_kdebug(LEAVE)) \
397 kleave(FMT, ##__VA_ARGS__); \
398 } while (0)
399
400 #define _debug(FMT, ...) \
401 do { \
402 if (__do_kdebug(DEBUG)) \
403 kdebug(FMT, ##__VA_ARGS__); \
404 } while (0)
405
406 #else
407 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
408 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
409 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
410 #endif
411
412 /*
413 * determine whether a particular optional debugging point should be logged
414 * - we need to go through three steps to persuade cpp to correctly join the
415 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix
416 */
417 #define ____do_kdebug(LEVEL, POINT) \
418 unlikely((fscache_debug & \
419 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
420 #define ___do_kdebug(LEVEL, POINT) \
421 ____do_kdebug(LEVEL, POINT)
422 #define __do_kdebug(POINT) \
423 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
424
425 #define FSCACHE_DEBUG_CACHE 0
426 #define FSCACHE_DEBUG_COOKIE 1
427 #define FSCACHE_DEBUG_PAGE 2
428 #define FSCACHE_DEBUG_OPERATION 3
429
430 #define FSCACHE_POINT_ENTER 1
431 #define FSCACHE_POINT_LEAVE 2
432 #define FSCACHE_POINT_DEBUG 4
433
434 #ifndef FSCACHE_DEBUG_LEVEL
435 #define FSCACHE_DEBUG_LEVEL CACHE
436 #endif
437
438 /*
439 * assertions
440 */
441 #if 1 /* defined(__KDEBUGALL) */
442
443 #define ASSERT(X) \
444 do { \
445 if (unlikely(!(X))) { \
446 pr_err("\n"); \
447 pr_err("Assertion failed\n"); \
448 BUG(); \
449 } \
450 } while (0)
451
452 #define ASSERTCMP(X, OP, Y) \
453 do { \
454 if (unlikely(!((X) OP (Y)))) { \
455 pr_err("\n"); \
456 pr_err("Assertion failed\n"); \
457 pr_err("%lx " #OP " %lx is false\n", \
458 (unsigned long)(X), (unsigned long)(Y)); \
459 BUG(); \
460 } \
461 } while (0)
462
463 #define ASSERTIF(C, X) \
464 do { \
465 if (unlikely((C) && !(X))) { \
466 pr_err("\n"); \
467 pr_err("Assertion failed\n"); \
468 BUG(); \
469 } \
470 } while (0)
471
472 #define ASSERTIFCMP(C, X, OP, Y) \
473 do { \
474 if (unlikely((C) && !((X) OP (Y)))) { \
475 pr_err("\n"); \
476 pr_err("Assertion failed\n"); \
477 pr_err("%lx " #OP " %lx is false\n", \
478 (unsigned long)(X), (unsigned long)(Y)); \
479 BUG(); \
480 } \
481 } while (0)
482
483 #else
484
485 #define ASSERT(X) do {} while (0)
486 #define ASSERTCMP(X, OP, Y) do {} while (0)
487 #define ASSERTIF(C, X) do {} while (0)
488 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
489
490 #endif /* assert or not */
491