[linux-2.6-block.git] / fs / fscache / internal.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
/* Internal definitions for FS-Cache
 *
 * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 */

#ifdef pr_fmt
#undef pr_fmt
#endif

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

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

/*
 * cache.c
 */
#ifdef CONFIG_PROC_FS
extern const struct seq_operations fscache_caches_seq_ops;
#endif
bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);

static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
{
	return smp_load_acquire(&cache->state);
}

static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
{
	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
}

static inline void fscache_set_cache_state(struct fscache_cache *cache,
					   enum fscache_cache_state new_state)
{
	smp_store_release(&cache->state, new_state);

}

static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
						 enum fscache_cache_state old_state,
						 enum fscache_cache_state new_state)
{
	return try_cmpxchg_release(&cache->state, &old_state, new_state);
}

/*
 * cookie.c
 */
extern struct kmem_cache *fscache_cookie_jar;
extern const struct seq_operations fscache_cookies_seq_ops;
extern struct timer_list fscache_cookie_lru_timer;

extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
					enum fscache_access_trace why);

static inline void fscache_see_cookie(struct fscache_cookie *cookie,
				      enum fscache_cookie_trace where)
{
	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
			     where);
}

/*
 * main.c
 */
extern unsigned fscache_debug;

extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);

/*
 * 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_volumes;
extern atomic_t fscache_n_volumes_collision;
extern atomic_t fscache_n_volumes_nomem;
extern atomic_t fscache_n_cookies;
extern atomic_t fscache_n_cookies_lru;
extern atomic_t fscache_n_cookies_lru_expired;
extern atomic_t fscache_n_cookies_lru_removed;
extern atomic_t fscache_n_cookies_lru_dropped;

extern atomic_t fscache_n_acquires;
extern atomic_t fscache_n_acquires_ok;
extern atomic_t fscache_n_acquires_oom;

extern atomic_t fscache_n_invalidates;

extern atomic_t fscache_n_relinquishes;
extern atomic_t fscache_n_relinquishes_retire;
extern atomic_t fscache_n_relinquishes_dropped;

extern atomic_t fscache_n_resizes;
extern atomic_t fscache_n_resizes_null;

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

/*
 * volume.c
 */
extern const struct seq_operations fscache_volumes_seq_ops;

struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
					  enum fscache_volume_trace where);
void fscache_put_volume(struct fscache_volume *volume,
			enum fscache_volume_trace where);
bool fscache_begin_volume_access(struct fscache_volume *volume,
				 struct fscache_cookie *cookie,
				 enum fscache_access_trace why);
void fscache_create_volume(struct fscache_volume *volume, bool wait);


/*****************************************************************************/
/*
 * debug tracing
 */
#define dbgprintk(FMT, ...) \
	printk("[%-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_OBJECT	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 */
Commit	Line	Data
1e1236b8 DH	1	/* SPDX-License-Identifier: GPL-2.0-or-later */
	2	/* Internal definitions for FS-Cache
	3	*
	4	* Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
	5	* Written by David Howells (dhowells@redhat.com)
	6	*/
	7
	8	#ifdef pr_fmt
	9	#undef pr_fmt
	10	#endif
	11
	12	#define pr_fmt(fmt) "FS-Cache: " fmt
	13
	14	#include <linux/slab.h>
	15	#include <linux/fscache-cache.h>
	16	#include <trace/events/fscache.h>
	17	#include <linux/sched.h>
	18	#include <linux/seq_file.h>
	19
9549332d DH	20	/*
	21	* cache.c
	22	*/
	23	#ifdef CONFIG_PROC_FS
	24	extern const struct seq_operations fscache_caches_seq_ops;
	25	#endif
23e12e28 DH	26	bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
23e12e28 DH	27	void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
9549332d DH	28	struct fscache_cache fscache_lookup_cache(const char name, bool is_cache);
	29	void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
	30
	31	static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
	32	{
	33	return smp_load_acquire(&cache->state);
	34	}
	35
	36	static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
	37	{
	38	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
	39	}
	40
	41	static inline void fscache_set_cache_state(struct fscache_cache *cache,
	42	enum fscache_cache_state new_state)
	43	{
	44	smp_store_release(&cache->state, new_state);
	45
	46	}
	47
	48	static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
	49	enum fscache_cache_state old_state,
	50	enum fscache_cache_state new_state)
	51	{
	52	return try_cmpxchg_release(&cache->state, &old_state, new_state);
	53	}
	54
7f3283ab DH	55	/*
	56	* cookie.c
	57	*/
	58	extern struct kmem_cache *fscache_cookie_jar;
	59	extern const struct seq_operations fscache_cookies_seq_ops;
12bb21a2	60	extern struct timer_list fscache_cookie_lru_timer;
7f3283ab DH	61
7f3283ab DH	62	extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
a7733fb6 DH	63	extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
	64	enum fscache_access_trace why);
	65
7f3283ab DH	66	static inline void fscache_see_cookie(struct fscache_cookie *cookie,
	67	enum fscache_cookie_trace where)
	68	{
	69	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
	70	where);
	71	}
	72
1e1236b8 DH	73	/*
	74	* main.c
	75	*/
	76	extern unsigned fscache_debug;
	77
e8a07c9d DH	78	extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
e8a07c9d DH	79
1e1236b8 DH	80	/*
	81	* proc.c
	82	*/
	83	#ifdef CONFIG_PROC_FS
	84	extern int __init fscache_proc_init(void);
	85	extern void fscache_proc_cleanup(void);
	86	#else
	87	#define fscache_proc_init() (0)
	88	#define fscache_proc_cleanup() do {} while (0)
	89	#endif
	90
	91	/*
	92	* stats.c
	93	*/
	94	#ifdef CONFIG_FSCACHE_STATS
62ab6335 DH	95	extern atomic_t fscache_n_volumes;
	96	extern atomic_t fscache_n_volumes_collision;
	97	extern atomic_t fscache_n_volumes_nomem;
7f3283ab	98	extern atomic_t fscache_n_cookies;
12bb21a2 DH	99	extern atomic_t fscache_n_cookies_lru;
	100	extern atomic_t fscache_n_cookies_lru_expired;
	101	extern atomic_t fscache_n_cookies_lru_removed;
	102	extern atomic_t fscache_n_cookies_lru_dropped;
7f3283ab DH	103
	104	extern atomic_t fscache_n_acquires;
	105	extern atomic_t fscache_n_acquires_ok;
	106	extern atomic_t fscache_n_acquires_oom;
	107
d24af13e DH	108	extern atomic_t fscache_n_invalidates;
d24af13e DH	109
7f3283ab DH	110	extern atomic_t fscache_n_relinquishes;
	111	extern atomic_t fscache_n_relinquishes_retire;
	112	extern atomic_t fscache_n_relinquishes_dropped;
1e1236b8	113
16a96bdf DH	114	extern atomic_t fscache_n_resizes;
	115	extern atomic_t fscache_n_resizes_null;
	116
1e1236b8 DH	117	static inline void fscache_stat(atomic_t *stat)
	118	{
	119	atomic_inc(stat);
	120	}
	121
	122	static inline void fscache_stat_d(atomic_t *stat)
	123	{
	124	atomic_dec(stat);
	125	}
	126
	127	#define __fscache_stat(stat) (stat)
	128
	129	int fscache_stats_show(struct seq_file m, void v);
	130	#else
	131
	132	#define __fscache_stat(stat) (NULL)
	133	#define fscache_stat(stat) do {} while (0)
	134	#define fscache_stat_d(stat) do {} while (0)
	135	#endif
	136
62ab6335 DH	137	/*
	138	* volume.c
	139	*/
	140	extern const struct seq_operations fscache_volumes_seq_ops;
	141
	142	struct fscache_volume fscache_get_volume(struct fscache_volume volume,
	143	enum fscache_volume_trace where);
	144	void fscache_put_volume(struct fscache_volume *volume,
	145	enum fscache_volume_trace where);
e6acd329 DH	146	bool fscache_begin_volume_access(struct fscache_volume *volume,
	147	struct fscache_cookie *cookie,
	148	enum fscache_access_trace why);
62ab6335 DH	149	void fscache_create_volume(struct fscache_volume *volume, bool wait);
62ab6335 DH	150
1e1236b8 DH	151
	152	/*****************************************************************************/
	153	/*
	154	* debug tracing
	155	*/
	156	#define dbgprintk(FMT, ...) \
	157	printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
	158
	159	#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
	160	#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
	161	#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
	162
	163	#define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
	164
	165	#ifdef __KDEBUG
	166	#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
	167	#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
	168	#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
	169
	170	#elif defined(CONFIG_FSCACHE_DEBUG)
	171	#define _enter(FMT, ...) \
	172	do { \
	173	if (__do_kdebug(ENTER)) \
	174	kenter(FMT, ##__VA_ARGS__); \
	175	} while (0)
	176
	177	#define _leave(FMT, ...) \
	178	do { \
	179	if (__do_kdebug(LEAVE)) \
	180	kleave(FMT, ##__VA_ARGS__); \
	181	} while (0)
	182
	183	#define _debug(FMT, ...) \
	184	do { \
	185	if (__do_kdebug(DEBUG)) \
	186	kdebug(FMT, ##__VA_ARGS__); \
	187	} while (0)
	188
	189	#else
	190	#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
	191	#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
	192	#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
	193	#endif
	194
	195	/*
	196	* determine whether a particular optional debugging point should be logged
	197	* - we need to go through three steps to persuade cpp to correctly join the
	198	* shorthand in FSCACHE_DEBUG_LEVEL with its prefix
	199	*/
	200	#define ____do_kdebug(LEVEL, POINT) \
	201	unlikely((fscache_debug & \
	202	(FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
	203	#define ___do_kdebug(LEVEL, POINT) \
	204	____do_kdebug(LEVEL, POINT)
	205	#define __do_kdebug(POINT) \
	206	___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
	207
	208	#define FSCACHE_DEBUG_CACHE 0
	209	#define FSCACHE_DEBUG_COOKIE 1
	210	#define FSCACHE_DEBUG_OBJECT 2
	211	#define FSCACHE_DEBUG_OPERATION 3
	212
	213	#define FSCACHE_POINT_ENTER 1
	214	#define FSCACHE_POINT_LEAVE 2
215	#define FSCACHE_POINT_DEBUG 4
216
217	#ifndef FSCACHE_DEBUG_LEVEL
218	#define FSCACHE_DEBUG_LEVEL CACHE
219	#endif
220
221	/*
222	* assertions
223	*/
224	#if 1 /* defined(__KDEBUGALL) */
225
226	#define ASSERT(X) \
227	do { \
228	if (unlikely(!(X))) { \
229	pr_err("\n"); \
230	pr_err("Assertion failed\n"); \
231	BUG(); \
232	} \
233	} while (0)
234
235	#define ASSERTCMP(X, OP, Y) \
236	do { \
237	if (unlikely(!((X) OP (Y)))) { \
238	pr_err("\n"); \
239	pr_err("Assertion failed\n"); \
240	pr_err("%lx " #OP " %lx is false\n", \
241	(unsigned long)(X), (unsigned long)(Y)); \
242	BUG(); \
243	} \
244	} while (0)
245
246	#define ASSERTIF(C, X) \
247	do { \
248	if (unlikely((C) && !(X))) { \
249	pr_err("\n"); \
250	pr_err("Assertion failed\n"); \
251	BUG(); \
252	} \
253	} while (0)
254
255	#define ASSERTIFCMP(C, X, OP, Y) \
256	do { \
257	if (unlikely((C) && !((X) OP (Y)))) { \
258	pr_err("\n"); \
259	pr_err("Assertion failed\n"); \
260	pr_err("%lx " #OP " %lx is false\n", \
261	(unsigned long)(X), (unsigned long)(Y)); \
262	BUG(); \
263	} \
264	} while (0)
265
266	#else
267
268	#define ASSERT(X) do {} while (0)
269	#define ASSERTCMP(X, OP, Y) do {} while (0)
270	#define ASSERTIF(C, X) do {} while (0)
271	#define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
272
273	#endif /* assert or not */