xref: /openbmc/linux/fs/fscache/internal.h (revision 04dc82e1)
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 
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 
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 
281 static inline void fscache_stat(atomic_t *stat)
282 {
283 	atomic_inc(stat);
284 }
285 
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  */
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 
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
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
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
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