xref: /linux/fs/netfs/internal.h (revision c38f4e96e605f17990e871214e6ea1496bc4e65f)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* Internal definitions for network filesystem support
3  *
4  * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7 
8 #include <linux/slab.h>
9 #include <linux/seq_file.h>
10 #include <linux/netfs.h>
11 #include <linux/fscache.h>
12 #include <linux/fscache-cache.h>
13 #include <trace/events/netfs.h>
14 #include <trace/events/fscache.h>
15 
16 #ifdef pr_fmt
17 #undef pr_fmt
18 #endif
19 
20 #define pr_fmt(fmt) "netfs: " fmt
21 
22 /*
23  * buffered_read.c
24  */
25 void netfs_rreq_unlock_folios(struct netfs_io_request *rreq);
26 int netfs_prefetch_for_write(struct file *file, struct folio *folio,
27 			     size_t offset, size_t len);
28 
29 /*
30  * io.c
31  */
32 int netfs_begin_read(struct netfs_io_request *rreq, bool sync);
33 
34 /*
35  * main.c
36  */
37 extern unsigned int netfs_debug;
38 extern struct list_head netfs_io_requests;
39 extern spinlock_t netfs_proc_lock;
40 
41 #ifdef CONFIG_PROC_FS
42 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq)
43 {
44 	spin_lock(&netfs_proc_lock);
45 	list_add_tail_rcu(&rreq->proc_link, &netfs_io_requests);
46 	spin_unlock(&netfs_proc_lock);
47 }
48 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq)
49 {
50 	if (!list_empty(&rreq->proc_link)) {
51 		spin_lock(&netfs_proc_lock);
52 		list_del_rcu(&rreq->proc_link);
53 		spin_unlock(&netfs_proc_lock);
54 	}
55 }
56 #else
57 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) {}
58 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq) {}
59 #endif
60 
61 /*
62  * misc.c
63  */
64 #define NETFS_FLAG_PUT_MARK		BIT(0)
65 #define NETFS_FLAG_PAGECACHE_MARK	BIT(1)
66 int netfs_xa_store_and_mark(struct xarray *xa, unsigned long index,
67 			    struct folio *folio, unsigned int flags,
68 			    gfp_t gfp_mask);
69 int netfs_add_folios_to_buffer(struct xarray *buffer,
70 			       struct address_space *mapping,
71 			       pgoff_t index, pgoff_t to, gfp_t gfp_mask);
72 void netfs_clear_buffer(struct xarray *buffer);
73 
74 /*
75  * objects.c
76  */
77 struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
78 					     struct file *file,
79 					     loff_t start, size_t len,
80 					     enum netfs_io_origin origin);
81 void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what);
82 void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async);
83 void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
84 		       enum netfs_rreq_ref_trace what);
85 struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq);
86 
87 static inline void netfs_see_request(struct netfs_io_request *rreq,
88 				     enum netfs_rreq_ref_trace what)
89 {
90 	trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what);
91 }
92 
93 /*
94  * output.c
95  */
96 int netfs_begin_write(struct netfs_io_request *wreq, bool may_wait,
97 		      enum netfs_write_trace what);
98 
99 /*
100  * stats.c
101  */
102 #ifdef CONFIG_NETFS_STATS
103 extern atomic_t netfs_n_rh_readahead;
104 extern atomic_t netfs_n_rh_readpage;
105 extern atomic_t netfs_n_rh_rreq;
106 extern atomic_t netfs_n_rh_sreq;
107 extern atomic_t netfs_n_rh_download;
108 extern atomic_t netfs_n_rh_download_done;
109 extern atomic_t netfs_n_rh_download_failed;
110 extern atomic_t netfs_n_rh_download_instead;
111 extern atomic_t netfs_n_rh_read;
112 extern atomic_t netfs_n_rh_read_done;
113 extern atomic_t netfs_n_rh_read_failed;
114 extern atomic_t netfs_n_rh_zero;
115 extern atomic_t netfs_n_rh_short_read;
116 extern atomic_t netfs_n_rh_write;
117 extern atomic_t netfs_n_rh_write_begin;
118 extern atomic_t netfs_n_rh_write_done;
119 extern atomic_t netfs_n_rh_write_failed;
120 extern atomic_t netfs_n_rh_write_zskip;
121 extern atomic_t netfs_n_wh_upload;
122 extern atomic_t netfs_n_wh_upload_done;
123 extern atomic_t netfs_n_wh_upload_failed;
124 extern atomic_t netfs_n_wh_write;
125 extern atomic_t netfs_n_wh_write_done;
126 extern atomic_t netfs_n_wh_write_failed;
127 
128 int netfs_stats_show(struct seq_file *m, void *v);
129 
130 static inline void netfs_stat(atomic_t *stat)
131 {
132 	atomic_inc(stat);
133 }
134 
135 static inline void netfs_stat_d(atomic_t *stat)
136 {
137 	atomic_dec(stat);
138 }
139 
140 #else
141 #define netfs_stat(x) do {} while(0)
142 #define netfs_stat_d(x) do {} while(0)
143 #endif
144 
145 /*
146  * Miscellaneous functions.
147  */
148 static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
149 {
150 #if IS_ENABLED(CONFIG_FSCACHE)
151 	struct fscache_cookie *cookie = ctx->cache;
152 
153 	return fscache_cookie_valid(cookie) && cookie->cache_priv &&
154 		fscache_cookie_enabled(cookie);
155 #else
156 	return false;
157 #endif
158 }
159 
160 /*
161  * Get a ref on a netfs group attached to a dirty page (e.g. a ceph snap).
162  */
163 static inline struct netfs_group *netfs_get_group(struct netfs_group *netfs_group)
164 {
165 	if (netfs_group)
166 		refcount_inc(&netfs_group->ref);
167 	return netfs_group;
168 }
169 
170 /*
171  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
172  */
173 static inline void netfs_put_group(struct netfs_group *netfs_group)
174 {
175 	if (netfs_group && refcount_dec_and_test(&netfs_group->ref))
176 		netfs_group->free(netfs_group);
177 }
178 
179 /*
180  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
181  */
182 static inline void netfs_put_group_many(struct netfs_group *netfs_group, int nr)
183 {
184 	if (netfs_group && refcount_sub_and_test(nr, &netfs_group->ref))
185 		netfs_group->free(netfs_group);
186 }
187 
188 /*
189  * fscache-cache.c
190  */
191 #ifdef CONFIG_PROC_FS
192 extern const struct seq_operations fscache_caches_seq_ops;
193 #endif
194 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
195 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
196 struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
197 void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
198 
199 static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
200 {
201 	return smp_load_acquire(&cache->state);
202 }
203 
204 static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
205 {
206 	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
207 }
208 
209 static inline void fscache_set_cache_state(struct fscache_cache *cache,
210 					   enum fscache_cache_state new_state)
211 {
212 	smp_store_release(&cache->state, new_state);
213 
214 }
215 
216 static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
217 						 enum fscache_cache_state old_state,
218 						 enum fscache_cache_state new_state)
219 {
220 	return try_cmpxchg_release(&cache->state, &old_state, new_state);
221 }
222 
223 /*
224  * fscache-cookie.c
225  */
226 extern struct kmem_cache *fscache_cookie_jar;
227 #ifdef CONFIG_PROC_FS
228 extern const struct seq_operations fscache_cookies_seq_ops;
229 #endif
230 extern struct timer_list fscache_cookie_lru_timer;
231 
232 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
233 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
234 					enum fscache_access_trace why);
235 
236 static inline void fscache_see_cookie(struct fscache_cookie *cookie,
237 				      enum fscache_cookie_trace where)
238 {
239 	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
240 			     where);
241 }
242 
243 /*
244  * fscache-main.c
245  */
246 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
247 #ifdef CONFIG_FSCACHE
248 int __init fscache_init(void);
249 void __exit fscache_exit(void);
250 #else
251 static inline int fscache_init(void) { return 0; }
252 static inline void fscache_exit(void) {}
253 #endif
254 
255 /*
256  * fscache-proc.c
257  */
258 #ifdef CONFIG_PROC_FS
259 extern int __init fscache_proc_init(void);
260 extern void fscache_proc_cleanup(void);
261 #else
262 #define fscache_proc_init()	(0)
263 #define fscache_proc_cleanup()	do {} while (0)
264 #endif
265 
266 /*
267  * fscache-stats.c
268  */
269 #ifdef CONFIG_FSCACHE_STATS
270 extern atomic_t fscache_n_volumes;
271 extern atomic_t fscache_n_volumes_collision;
272 extern atomic_t fscache_n_volumes_nomem;
273 extern atomic_t fscache_n_cookies;
274 extern atomic_t fscache_n_cookies_lru;
275 extern atomic_t fscache_n_cookies_lru_expired;
276 extern atomic_t fscache_n_cookies_lru_removed;
277 extern atomic_t fscache_n_cookies_lru_dropped;
278 
279 extern atomic_t fscache_n_acquires;
280 extern atomic_t fscache_n_acquires_ok;
281 extern atomic_t fscache_n_acquires_oom;
282 
283 extern atomic_t fscache_n_invalidates;
284 
285 extern atomic_t fscache_n_relinquishes;
286 extern atomic_t fscache_n_relinquishes_retire;
287 extern atomic_t fscache_n_relinquishes_dropped;
288 
289 extern atomic_t fscache_n_resizes;
290 extern atomic_t fscache_n_resizes_null;
291 
292 static inline void fscache_stat(atomic_t *stat)
293 {
294 	atomic_inc(stat);
295 }
296 
297 static inline void fscache_stat_d(atomic_t *stat)
298 {
299 	atomic_dec(stat);
300 }
301 
302 #define __fscache_stat(stat) (stat)
303 
304 int fscache_stats_show(struct seq_file *m);
305 #else
306 
307 #define __fscache_stat(stat) (NULL)
308 #define fscache_stat(stat) do {} while (0)
309 #define fscache_stat_d(stat) do {} while (0)
310 
311 static inline int fscache_stats_show(struct seq_file *m) { return 0; }
312 #endif
313 
314 /*
315  * fscache-volume.c
316  */
317 #ifdef CONFIG_PROC_FS
318 extern const struct seq_operations fscache_volumes_seq_ops;
319 #endif
320 
321 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
322 					  enum fscache_volume_trace where);
323 void fscache_put_volume(struct fscache_volume *volume,
324 			enum fscache_volume_trace where);
325 bool fscache_begin_volume_access(struct fscache_volume *volume,
326 				 struct fscache_cookie *cookie,
327 				 enum fscache_access_trace why);
328 void fscache_create_volume(struct fscache_volume *volume, bool wait);
329 
330 /*****************************************************************************/
331 /*
332  * debug tracing
333  */
334 #define dbgprintk(FMT, ...) \
335 	printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
336 
337 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
338 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
339 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
340 
341 #ifdef __KDEBUG
342 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
343 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
344 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
345 
346 #elif defined(CONFIG_NETFS_DEBUG)
347 #define _enter(FMT, ...)			\
348 do {						\
349 	if (netfs_debug)			\
350 		kenter(FMT, ##__VA_ARGS__);	\
351 } while (0)
352 
353 #define _leave(FMT, ...)			\
354 do {						\
355 	if (netfs_debug)			\
356 		kleave(FMT, ##__VA_ARGS__);	\
357 } while (0)
358 
359 #define _debug(FMT, ...)			\
360 do {						\
361 	if (netfs_debug)			\
362 		kdebug(FMT, ##__VA_ARGS__);	\
363 } while (0)
364 
365 #else
366 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
367 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
368 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
369 #endif
370 
371 /*
372  * assertions
373  */
374 #if 1 /* defined(__KDEBUGALL) */
375 
376 #define ASSERT(X)							\
377 do {									\
378 	if (unlikely(!(X))) {						\
379 		pr_err("\n");					\
380 		pr_err("Assertion failed\n");	\
381 		BUG();							\
382 	}								\
383 } while (0)
384 
385 #define ASSERTCMP(X, OP, Y)						\
386 do {									\
387 	if (unlikely(!((X) OP (Y)))) {					\
388 		pr_err("\n");					\
389 		pr_err("Assertion failed\n");	\
390 		pr_err("%lx " #OP " %lx is false\n",		\
391 		       (unsigned long)(X), (unsigned long)(Y));		\
392 		BUG();							\
393 	}								\
394 } while (0)
395 
396 #define ASSERTIF(C, X)							\
397 do {									\
398 	if (unlikely((C) && !(X))) {					\
399 		pr_err("\n");					\
400 		pr_err("Assertion failed\n");	\
401 		BUG();							\
402 	}								\
403 } while (0)
404 
405 #define ASSERTIFCMP(C, X, OP, Y)					\
406 do {									\
407 	if (unlikely((C) && !((X) OP (Y)))) {				\
408 		pr_err("\n");					\
409 		pr_err("Assertion failed\n");	\
410 		pr_err("%lx " #OP " %lx is false\n",		\
411 		       (unsigned long)(X), (unsigned long)(Y));		\
412 		BUG();							\
413 	}								\
414 } while (0)
415 
416 #else
417 
418 #define ASSERT(X)			do {} while (0)
419 #define ASSERTCMP(X, OP, Y)		do {} while (0)
420 #define ASSERTIF(C, X)			do {} while (0)
421 #define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)
422 
423 #endif /* assert or not */
424