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
20 /*
21 * cache.c
22 */
23 #ifdef CONFIG_PROC_FS
24 extern const struct seq_operations fscache_caches_seq_ops;
25 #endif
26 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
27 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
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
fscache_cache_state(const struct fscache_cache * cache)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
fscache_cache_is_live(const struct fscache_cache * cache)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
fscache_set_cache_state(struct fscache_cache * cache,enum fscache_cache_state new_state)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
fscache_set_cache_state_maybe(struct fscache_cache * cache,enum fscache_cache_state old_state,enum fscache_cache_state new_state)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
55 /*
56 * cookie.c
57 */
58 extern struct kmem_cache *fscache_cookie_jar;
59 #ifdef CONFIG_PROC_FS
60 extern const struct seq_operations fscache_cookies_seq_ops;
61 #endif
62 extern struct timer_list fscache_cookie_lru_timer;
63
64 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
65 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
66 enum fscache_access_trace why);
67
fscache_see_cookie(struct fscache_cookie * cookie,enum fscache_cookie_trace where)68 static inline void fscache_see_cookie(struct fscache_cookie *cookie,
69 enum fscache_cookie_trace where)
70 {
71 trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
72 where);
73 }
74
75 /*
76 * main.c
77 */
78 extern unsigned fscache_debug;
79
80 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
81
82 /*
83 * proc.c
84 */
85 #ifdef CONFIG_PROC_FS
86 extern int __init fscache_proc_init(void);
87 extern void fscache_proc_cleanup(void);
88 #else
89 #define fscache_proc_init() (0)
90 #define fscache_proc_cleanup() do {} while (0)
91 #endif
92
93 /*
94 * stats.c
95 */
96 #ifdef CONFIG_FSCACHE_STATS
97 extern atomic_t fscache_n_volumes;
98 extern atomic_t fscache_n_volumes_collision;
99 extern atomic_t fscache_n_volumes_nomem;
100 extern atomic_t fscache_n_cookies;
101 extern atomic_t fscache_n_cookies_lru;
102 extern atomic_t fscache_n_cookies_lru_expired;
103 extern atomic_t fscache_n_cookies_lru_removed;
104 extern atomic_t fscache_n_cookies_lru_dropped;
105
106 extern atomic_t fscache_n_acquires;
107 extern atomic_t fscache_n_acquires_ok;
108 extern atomic_t fscache_n_acquires_oom;
109
110 extern atomic_t fscache_n_invalidates;
111
112 extern atomic_t fscache_n_relinquishes;
113 extern atomic_t fscache_n_relinquishes_retire;
114 extern atomic_t fscache_n_relinquishes_dropped;
115
116 extern atomic_t fscache_n_resizes;
117 extern atomic_t fscache_n_resizes_null;
118
fscache_stat(atomic_t * stat)119 static inline void fscache_stat(atomic_t *stat)
120 {
121 atomic_inc(stat);
122 }
123
fscache_stat_d(atomic_t * stat)124 static inline void fscache_stat_d(atomic_t *stat)
125 {
126 atomic_dec(stat);
127 }
128
129 #define __fscache_stat(stat) (stat)
130
131 int fscache_stats_show(struct seq_file *m, void *v);
132 #else
133
134 #define __fscache_stat(stat) (NULL)
135 #define fscache_stat(stat) do {} while (0)
136 #define fscache_stat_d(stat) do {} while (0)
137 #endif
138
139 /*
140 * volume.c
141 */
142 #ifdef CONFIG_PROC_FS
143 extern const struct seq_operations fscache_volumes_seq_ops;
144 #endif
145
146 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
147 enum fscache_volume_trace where);
148 bool fscache_begin_volume_access(struct fscache_volume *volume,
149 struct fscache_cookie *cookie,
150 enum fscache_access_trace why);
151 void fscache_create_volume(struct fscache_volume *volume, bool wait);
152
153
154 /*****************************************************************************/
155 /*
156 * debug tracing
157 */
158 #define dbgprintk(FMT, ...) \
159 printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
160
161 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
162 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
163 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
164
165 #define kjournal(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
166
167 #ifdef __KDEBUG
168 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
169 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
170 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
171
172 #elif defined(CONFIG_FSCACHE_DEBUG)
173 #define _enter(FMT, ...) \
174 do { \
175 if (__do_kdebug(ENTER)) \
176 kenter(FMT, ##__VA_ARGS__); \
177 } while (0)
178
179 #define _leave(FMT, ...) \
180 do { \
181 if (__do_kdebug(LEAVE)) \
182 kleave(FMT, ##__VA_ARGS__); \
183 } while (0)
184
185 #define _debug(FMT, ...) \
186 do { \
187 if (__do_kdebug(DEBUG)) \
188 kdebug(FMT, ##__VA_ARGS__); \
189 } while (0)
190
191 #else
192 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
193 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
194 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
195 #endif
196
197 /*
198 * determine whether a particular optional debugging point should be logged
199 * - we need to go through three steps to persuade cpp to correctly join the
200 * shorthand in FSCACHE_DEBUG_LEVEL with its prefix
201 */
202 #define ____do_kdebug(LEVEL, POINT) \
203 unlikely((fscache_debug & \
204 (FSCACHE_POINT_##POINT << (FSCACHE_DEBUG_ ## LEVEL * 3))))
205 #define ___do_kdebug(LEVEL, POINT) \
206 ____do_kdebug(LEVEL, POINT)
207 #define __do_kdebug(POINT) \
208 ___do_kdebug(FSCACHE_DEBUG_LEVEL, POINT)
209
210 #define FSCACHE_DEBUG_CACHE 0
211 #define FSCACHE_DEBUG_COOKIE 1
212 #define FSCACHE_DEBUG_OBJECT 2
213 #define FSCACHE_DEBUG_OPERATION 3
214
215 #define FSCACHE_POINT_ENTER 1
216 #define FSCACHE_POINT_LEAVE 2
217 #define FSCACHE_POINT_DEBUG 4
218
219 #ifndef FSCACHE_DEBUG_LEVEL
220 #define FSCACHE_DEBUG_LEVEL CACHE
221 #endif
222
223 /*
224 * assertions
225 */
226 #if 1 /* defined(__KDEBUGALL) */
227
228 #define ASSERT(X) \
229 do { \
230 if (unlikely(!(X))) { \
231 pr_err("\n"); \
232 pr_err("Assertion failed\n"); \
233 BUG(); \
234 } \
235 } while (0)
236
237 #define ASSERTCMP(X, OP, Y) \
238 do { \
239 if (unlikely(!((X) OP (Y)))) { \
240 pr_err("\n"); \
241 pr_err("Assertion failed\n"); \
242 pr_err("%lx " #OP " %lx is false\n", \
243 (unsigned long)(X), (unsigned long)(Y)); \
244 BUG(); \
245 } \
246 } while (0)
247
248 #define ASSERTIF(C, X) \
249 do { \
250 if (unlikely((C) && !(X))) { \
251 pr_err("\n"); \
252 pr_err("Assertion failed\n"); \
253 BUG(); \
254 } \
255 } while (0)
256
257 #define ASSERTIFCMP(C, X, OP, Y) \
258 do { \
259 if (unlikely((C) && !((X) OP (Y)))) { \
260 pr_err("\n"); \
261 pr_err("Assertion failed\n"); \
262 pr_err("%lx " #OP " %lx is false\n", \
263 (unsigned long)(X), (unsigned long)(Y)); \
264 BUG(); \
265 } \
266 } while (0)
267
268 #else
269
270 #define ASSERT(X) do {} while (0)
271 #define ASSERTCMP(X, OP, Y) do {} while (0)
272 #define ASSERTIF(C, X) do {} while (0)
273 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
274
275 #endif /* assert or not */
276