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