xref: /linux/fs/netfs/internal.h (revision 9e56ff53b4115875667760445b028357848b4748)
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 struct netfs_io_request *netfs_begin_writethrough(struct kiocb *iocb, size_t len);
99 int netfs_advance_writethrough(struct netfs_io_request *wreq, size_t copied, bool to_page_end);
100 int netfs_end_writethrough(struct netfs_io_request *wreq, struct kiocb *iocb);
101 
102 /*
103  * stats.c
104  */
105 #ifdef CONFIG_NETFS_STATS
106 extern atomic_t netfs_n_rh_dio_read;
107 extern atomic_t netfs_n_rh_dio_write;
108 extern atomic_t netfs_n_rh_readahead;
109 extern atomic_t netfs_n_rh_readpage;
110 extern atomic_t netfs_n_rh_rreq;
111 extern atomic_t netfs_n_rh_sreq;
112 extern atomic_t netfs_n_rh_download;
113 extern atomic_t netfs_n_rh_download_done;
114 extern atomic_t netfs_n_rh_download_failed;
115 extern atomic_t netfs_n_rh_download_instead;
116 extern atomic_t netfs_n_rh_read;
117 extern atomic_t netfs_n_rh_read_done;
118 extern atomic_t netfs_n_rh_read_failed;
119 extern atomic_t netfs_n_rh_zero;
120 extern atomic_t netfs_n_rh_short_read;
121 extern atomic_t netfs_n_rh_write;
122 extern atomic_t netfs_n_rh_write_begin;
123 extern atomic_t netfs_n_rh_write_done;
124 extern atomic_t netfs_n_rh_write_failed;
125 extern atomic_t netfs_n_rh_write_zskip;
126 extern atomic_t netfs_n_wh_wstream_conflict;
127 extern atomic_t netfs_n_wh_upload;
128 extern atomic_t netfs_n_wh_upload_done;
129 extern atomic_t netfs_n_wh_upload_failed;
130 extern atomic_t netfs_n_wh_write;
131 extern atomic_t netfs_n_wh_write_done;
132 extern atomic_t netfs_n_wh_write_failed;
133 
134 int netfs_stats_show(struct seq_file *m, void *v);
135 
136 static inline void netfs_stat(atomic_t *stat)
137 {
138 	atomic_inc(stat);
139 }
140 
141 static inline void netfs_stat_d(atomic_t *stat)
142 {
143 	atomic_dec(stat);
144 }
145 
146 #else
147 #define netfs_stat(x) do {} while(0)
148 #define netfs_stat_d(x) do {} while(0)
149 #endif
150 
151 /*
152  * Miscellaneous functions.
153  */
154 static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
155 {
156 #if IS_ENABLED(CONFIG_FSCACHE)
157 	struct fscache_cookie *cookie = ctx->cache;
158 
159 	return fscache_cookie_valid(cookie) && cookie->cache_priv &&
160 		fscache_cookie_enabled(cookie);
161 #else
162 	return false;
163 #endif
164 }
165 
166 /*
167  * Get a ref on a netfs group attached to a dirty page (e.g. a ceph snap).
168  */
169 static inline struct netfs_group *netfs_get_group(struct netfs_group *netfs_group)
170 {
171 	if (netfs_group)
172 		refcount_inc(&netfs_group->ref);
173 	return netfs_group;
174 }
175 
176 /*
177  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
178  */
179 static inline void netfs_put_group(struct netfs_group *netfs_group)
180 {
181 	if (netfs_group && refcount_dec_and_test(&netfs_group->ref))
182 		netfs_group->free(netfs_group);
183 }
184 
185 /*
186  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
187  */
188 static inline void netfs_put_group_many(struct netfs_group *netfs_group, int nr)
189 {
190 	if (netfs_group && refcount_sub_and_test(nr, &netfs_group->ref))
191 		netfs_group->free(netfs_group);
192 }
193 
194 /*
195  * fscache-cache.c
196  */
197 #ifdef CONFIG_PROC_FS
198 extern const struct seq_operations fscache_caches_seq_ops;
199 #endif
200 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
201 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
202 struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
203 void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
204 
205 static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
206 {
207 	return smp_load_acquire(&cache->state);
208 }
209 
210 static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
211 {
212 	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
213 }
214 
215 static inline void fscache_set_cache_state(struct fscache_cache *cache,
216 					   enum fscache_cache_state new_state)
217 {
218 	smp_store_release(&cache->state, new_state);
219 
220 }
221 
222 static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
223 						 enum fscache_cache_state old_state,
224 						 enum fscache_cache_state new_state)
225 {
226 	return try_cmpxchg_release(&cache->state, &old_state, new_state);
227 }
228 
229 /*
230  * fscache-cookie.c
231  */
232 extern struct kmem_cache *fscache_cookie_jar;
233 #ifdef CONFIG_PROC_FS
234 extern const struct seq_operations fscache_cookies_seq_ops;
235 #endif
236 extern struct timer_list fscache_cookie_lru_timer;
237 
238 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
239 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
240 					enum fscache_access_trace why);
241 
242 static inline void fscache_see_cookie(struct fscache_cookie *cookie,
243 				      enum fscache_cookie_trace where)
244 {
245 	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
246 			     where);
247 }
248 
249 /*
250  * fscache-main.c
251  */
252 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
253 #ifdef CONFIG_FSCACHE
254 int __init fscache_init(void);
255 void __exit fscache_exit(void);
256 #else
257 static inline int fscache_init(void) { return 0; }
258 static inline void fscache_exit(void) {}
259 #endif
260 
261 /*
262  * fscache-proc.c
263  */
264 #ifdef CONFIG_PROC_FS
265 extern int __init fscache_proc_init(void);
266 extern void fscache_proc_cleanup(void);
267 #else
268 #define fscache_proc_init()	(0)
269 #define fscache_proc_cleanup()	do {} while (0)
270 #endif
271 
272 /*
273  * fscache-stats.c
274  */
275 #ifdef CONFIG_FSCACHE_STATS
276 extern atomic_t fscache_n_volumes;
277 extern atomic_t fscache_n_volumes_collision;
278 extern atomic_t fscache_n_volumes_nomem;
279 extern atomic_t fscache_n_cookies;
280 extern atomic_t fscache_n_cookies_lru;
281 extern atomic_t fscache_n_cookies_lru_expired;
282 extern atomic_t fscache_n_cookies_lru_removed;
283 extern atomic_t fscache_n_cookies_lru_dropped;
284 
285 extern atomic_t fscache_n_acquires;
286 extern atomic_t fscache_n_acquires_ok;
287 extern atomic_t fscache_n_acquires_oom;
288 
289 extern atomic_t fscache_n_invalidates;
290 
291 extern atomic_t fscache_n_relinquishes;
292 extern atomic_t fscache_n_relinquishes_retire;
293 extern atomic_t fscache_n_relinquishes_dropped;
294 
295 extern atomic_t fscache_n_resizes;
296 extern atomic_t fscache_n_resizes_null;
297 
298 static inline void fscache_stat(atomic_t *stat)
299 {
300 	atomic_inc(stat);
301 }
302 
303 static inline void fscache_stat_d(atomic_t *stat)
304 {
305 	atomic_dec(stat);
306 }
307 
308 #define __fscache_stat(stat) (stat)
309 
310 int fscache_stats_show(struct seq_file *m);
311 #else
312 
313 #define __fscache_stat(stat) (NULL)
314 #define fscache_stat(stat) do {} while (0)
315 #define fscache_stat_d(stat) do {} while (0)
316 
317 static inline int fscache_stats_show(struct seq_file *m) { return 0; }
318 #endif
319 
320 /*
321  * fscache-volume.c
322  */
323 #ifdef CONFIG_PROC_FS
324 extern const struct seq_operations fscache_volumes_seq_ops;
325 #endif
326 
327 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
328 					  enum fscache_volume_trace where);
329 void fscache_put_volume(struct fscache_volume *volume,
330 			enum fscache_volume_trace where);
331 bool fscache_begin_volume_access(struct fscache_volume *volume,
332 				 struct fscache_cookie *cookie,
333 				 enum fscache_access_trace why);
334 void fscache_create_volume(struct fscache_volume *volume, bool wait);
335 
336 /*****************************************************************************/
337 /*
338  * debug tracing
339  */
340 #define dbgprintk(FMT, ...) \
341 	printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
342 
343 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
344 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
345 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
346 
347 #ifdef __KDEBUG
348 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
349 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
350 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
351 
352 #elif defined(CONFIG_NETFS_DEBUG)
353 #define _enter(FMT, ...)			\
354 do {						\
355 	if (netfs_debug)			\
356 		kenter(FMT, ##__VA_ARGS__);	\
357 } while (0)
358 
359 #define _leave(FMT, ...)			\
360 do {						\
361 	if (netfs_debug)			\
362 		kleave(FMT, ##__VA_ARGS__);	\
363 } while (0)
364 
365 #define _debug(FMT, ...)			\
366 do {						\
367 	if (netfs_debug)			\
368 		kdebug(FMT, ##__VA_ARGS__);	\
369 } while (0)
370 
371 #else
372 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
373 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
374 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
375 #endif
376 
377 /*
378  * assertions
379  */
380 #if 1 /* defined(__KDEBUGALL) */
381 
382 #define ASSERT(X)							\
383 do {									\
384 	if (unlikely(!(X))) {						\
385 		pr_err("\n");					\
386 		pr_err("Assertion failed\n");	\
387 		BUG();							\
388 	}								\
389 } while (0)
390 
391 #define ASSERTCMP(X, OP, Y)						\
392 do {									\
393 	if (unlikely(!((X) OP (Y)))) {					\
394 		pr_err("\n");					\
395 		pr_err("Assertion failed\n");	\
396 		pr_err("%lx " #OP " %lx is false\n",		\
397 		       (unsigned long)(X), (unsigned long)(Y));		\
398 		BUG();							\
399 	}								\
400 } while (0)
401 
402 #define ASSERTIF(C, X)							\
403 do {									\
404 	if (unlikely((C) && !(X))) {					\
405 		pr_err("\n");					\
406 		pr_err("Assertion failed\n");	\
407 		BUG();							\
408 	}								\
409 } while (0)
410 
411 #define ASSERTIFCMP(C, X, OP, Y)					\
412 do {									\
413 	if (unlikely((C) && !((X) OP (Y)))) {				\
414 		pr_err("\n");					\
415 		pr_err("Assertion failed\n");	\
416 		pr_err("%lx " #OP " %lx is false\n",		\
417 		       (unsigned long)(X), (unsigned long)(Y));		\
418 		BUG();							\
419 	}								\
420 } while (0)
421 
422 #else
423 
424 #define ASSERT(X)			do {} while (0)
425 #define ASSERTCMP(X, OP, Y)		do {} while (0)
426 #define ASSERTIF(C, X)			do {} while (0)
427 #define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)
428 
429 #endif /* assert or not */
430