xref: /linux/fs/netfs/internal.h (revision 906fd46a65383cd639e5eec72a047efc33045d86)
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 extern mempool_t netfs_request_pool;
41 extern mempool_t netfs_subrequest_pool;
42 
43 #ifdef CONFIG_PROC_FS
44 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq)
45 {
46 	spin_lock(&netfs_proc_lock);
47 	list_add_tail_rcu(&rreq->proc_link, &netfs_io_requests);
48 	spin_unlock(&netfs_proc_lock);
49 }
50 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq)
51 {
52 	if (!list_empty(&rreq->proc_link)) {
53 		spin_lock(&netfs_proc_lock);
54 		list_del_rcu(&rreq->proc_link);
55 		spin_unlock(&netfs_proc_lock);
56 	}
57 }
58 #else
59 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) {}
60 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq) {}
61 #endif
62 
63 /*
64  * misc.c
65  */
66 #define NETFS_FLAG_PUT_MARK		BIT(0)
67 #define NETFS_FLAG_PAGECACHE_MARK	BIT(1)
68 int netfs_xa_store_and_mark(struct xarray *xa, unsigned long index,
69 			    struct folio *folio, unsigned int flags,
70 			    gfp_t gfp_mask);
71 int netfs_add_folios_to_buffer(struct xarray *buffer,
72 			       struct address_space *mapping,
73 			       pgoff_t index, pgoff_t to, gfp_t gfp_mask);
74 void netfs_clear_buffer(struct xarray *buffer);
75 
76 /*
77  * objects.c
78  */
79 struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
80 					     struct file *file,
81 					     loff_t start, size_t len,
82 					     enum netfs_io_origin origin);
83 void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what);
84 void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async);
85 void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
86 		       enum netfs_rreq_ref_trace what);
87 struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq);
88 
89 static inline void netfs_see_request(struct netfs_io_request *rreq,
90 				     enum netfs_rreq_ref_trace what)
91 {
92 	trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what);
93 }
94 
95 /*
96  * stats.c
97  */
98 #ifdef CONFIG_NETFS_STATS
99 extern atomic_t netfs_n_rh_dio_read;
100 extern atomic_t netfs_n_rh_readahead;
101 extern atomic_t netfs_n_rh_read_folio;
102 extern atomic_t netfs_n_rh_rreq;
103 extern atomic_t netfs_n_rh_sreq;
104 extern atomic_t netfs_n_rh_download;
105 extern atomic_t netfs_n_rh_download_done;
106 extern atomic_t netfs_n_rh_download_failed;
107 extern atomic_t netfs_n_rh_download_instead;
108 extern atomic_t netfs_n_rh_read;
109 extern atomic_t netfs_n_rh_read_done;
110 extern atomic_t netfs_n_rh_read_failed;
111 extern atomic_t netfs_n_rh_zero;
112 extern atomic_t netfs_n_rh_short_read;
113 extern atomic_t netfs_n_rh_write;
114 extern atomic_t netfs_n_rh_write_begin;
115 extern atomic_t netfs_n_rh_write_done;
116 extern atomic_t netfs_n_rh_write_failed;
117 extern atomic_t netfs_n_rh_write_zskip;
118 extern atomic_t netfs_n_wh_buffered_write;
119 extern atomic_t netfs_n_wh_writethrough;
120 extern atomic_t netfs_n_wh_dio_write;
121 extern atomic_t netfs_n_wh_writepages;
122 extern atomic_t netfs_n_wh_wstream_conflict;
123 extern atomic_t netfs_n_wh_upload;
124 extern atomic_t netfs_n_wh_upload_done;
125 extern atomic_t netfs_n_wh_upload_failed;
126 extern atomic_t netfs_n_wh_write;
127 extern atomic_t netfs_n_wh_write_done;
128 extern atomic_t netfs_n_wh_write_failed;
129 
130 int netfs_stats_show(struct seq_file *m, void *v);
131 
132 static inline void netfs_stat(atomic_t *stat)
133 {
134 	atomic_inc(stat);
135 }
136 
137 static inline void netfs_stat_d(atomic_t *stat)
138 {
139 	atomic_dec(stat);
140 }
141 
142 #else
143 #define netfs_stat(x) do {} while(0)
144 #define netfs_stat_d(x) do {} while(0)
145 #endif
146 
147 /*
148  * write_collect.c
149  */
150 int netfs_folio_written_back(struct folio *folio);
151 void netfs_write_collection_worker(struct work_struct *work);
152 void netfs_wake_write_collector(struct netfs_io_request *wreq, bool was_async);
153 
154 /*
155  * write_issue.c
156  */
157 struct netfs_io_request *netfs_create_write_req(struct address_space *mapping,
158 						struct file *file,
159 						loff_t start,
160 						enum netfs_io_origin origin);
161 void netfs_reissue_write(struct netfs_io_stream *stream,
162 			 struct netfs_io_subrequest *subreq);
163 int netfs_advance_write(struct netfs_io_request *wreq,
164 			struct netfs_io_stream *stream,
165 			loff_t start, size_t len, bool to_eof);
166 struct netfs_io_request *netfs_begin_writethrough(struct kiocb *iocb, size_t len);
167 int netfs_advance_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc,
168 			       struct folio *folio, size_t copied, bool to_page_end,
169 			       struct folio **writethrough_cache);
170 int netfs_end_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc,
171 			   struct folio *writethrough_cache);
172 int netfs_unbuffered_write(struct netfs_io_request *wreq, bool may_wait, size_t len);
173 
174 /*
175  * Miscellaneous functions.
176  */
177 static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
178 {
179 #if IS_ENABLED(CONFIG_FSCACHE)
180 	struct fscache_cookie *cookie = ctx->cache;
181 
182 	return fscache_cookie_valid(cookie) && cookie->cache_priv &&
183 		fscache_cookie_enabled(cookie);
184 #else
185 	return false;
186 #endif
187 }
188 
189 /*
190  * Get a ref on a netfs group attached to a dirty page (e.g. a ceph snap).
191  */
192 static inline struct netfs_group *netfs_get_group(struct netfs_group *netfs_group)
193 {
194 	if (netfs_group && netfs_group != NETFS_FOLIO_COPY_TO_CACHE)
195 		refcount_inc(&netfs_group->ref);
196 	return netfs_group;
197 }
198 
199 /*
200  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
201  */
202 static inline void netfs_put_group(struct netfs_group *netfs_group)
203 {
204 	if (netfs_group &&
205 	    netfs_group != NETFS_FOLIO_COPY_TO_CACHE &&
206 	    refcount_dec_and_test(&netfs_group->ref))
207 		netfs_group->free(netfs_group);
208 }
209 
210 /*
211  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
212  */
213 static inline void netfs_put_group_many(struct netfs_group *netfs_group, int nr)
214 {
215 	if (netfs_group &&
216 	    netfs_group != NETFS_FOLIO_COPY_TO_CACHE &&
217 	    refcount_sub_and_test(nr, &netfs_group->ref))
218 		netfs_group->free(netfs_group);
219 }
220 
221 /*
222  * fscache-cache.c
223  */
224 #ifdef CONFIG_PROC_FS
225 extern const struct seq_operations fscache_caches_seq_ops;
226 #endif
227 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
228 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
229 struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
230 void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
231 
232 static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
233 {
234 	return smp_load_acquire(&cache->state);
235 }
236 
237 static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
238 {
239 	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
240 }
241 
242 static inline void fscache_set_cache_state(struct fscache_cache *cache,
243 					   enum fscache_cache_state new_state)
244 {
245 	smp_store_release(&cache->state, new_state);
246 
247 }
248 
249 static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
250 						 enum fscache_cache_state old_state,
251 						 enum fscache_cache_state new_state)
252 {
253 	return try_cmpxchg_release(&cache->state, &old_state, new_state);
254 }
255 
256 /*
257  * fscache-cookie.c
258  */
259 extern struct kmem_cache *fscache_cookie_jar;
260 #ifdef CONFIG_PROC_FS
261 extern const struct seq_operations fscache_cookies_seq_ops;
262 #endif
263 extern struct timer_list fscache_cookie_lru_timer;
264 
265 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
266 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
267 					enum fscache_access_trace why);
268 
269 static inline void fscache_see_cookie(struct fscache_cookie *cookie,
270 				      enum fscache_cookie_trace where)
271 {
272 	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
273 			     where);
274 }
275 
276 /*
277  * fscache-main.c
278  */
279 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
280 #ifdef CONFIG_FSCACHE
281 int __init fscache_init(void);
282 void __exit fscache_exit(void);
283 #else
284 static inline int fscache_init(void) { return 0; }
285 static inline void fscache_exit(void) {}
286 #endif
287 
288 /*
289  * fscache-proc.c
290  */
291 #ifdef CONFIG_PROC_FS
292 extern int __init fscache_proc_init(void);
293 extern void fscache_proc_cleanup(void);
294 #else
295 #define fscache_proc_init()	(0)
296 #define fscache_proc_cleanup()	do {} while (0)
297 #endif
298 
299 /*
300  * fscache-stats.c
301  */
302 #ifdef CONFIG_FSCACHE_STATS
303 extern atomic_t fscache_n_volumes;
304 extern atomic_t fscache_n_volumes_collision;
305 extern atomic_t fscache_n_volumes_nomem;
306 extern atomic_t fscache_n_cookies;
307 extern atomic_t fscache_n_cookies_lru;
308 extern atomic_t fscache_n_cookies_lru_expired;
309 extern atomic_t fscache_n_cookies_lru_removed;
310 extern atomic_t fscache_n_cookies_lru_dropped;
311 
312 extern atomic_t fscache_n_acquires;
313 extern atomic_t fscache_n_acquires_ok;
314 extern atomic_t fscache_n_acquires_oom;
315 
316 extern atomic_t fscache_n_invalidates;
317 
318 extern atomic_t fscache_n_relinquishes;
319 extern atomic_t fscache_n_relinquishes_retire;
320 extern atomic_t fscache_n_relinquishes_dropped;
321 
322 extern atomic_t fscache_n_resizes;
323 extern atomic_t fscache_n_resizes_null;
324 
325 static inline void fscache_stat(atomic_t *stat)
326 {
327 	atomic_inc(stat);
328 }
329 
330 static inline void fscache_stat_d(atomic_t *stat)
331 {
332 	atomic_dec(stat);
333 }
334 
335 #define __fscache_stat(stat) (stat)
336 
337 int fscache_stats_show(struct seq_file *m);
338 #else
339 
340 #define __fscache_stat(stat) (NULL)
341 #define fscache_stat(stat) do {} while (0)
342 #define fscache_stat_d(stat) do {} while (0)
343 
344 static inline int fscache_stats_show(struct seq_file *m) { return 0; }
345 #endif
346 
347 /*
348  * fscache-volume.c
349  */
350 #ifdef CONFIG_PROC_FS
351 extern const struct seq_operations fscache_volumes_seq_ops;
352 #endif
353 
354 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
355 					  enum fscache_volume_trace where);
356 void fscache_put_volume(struct fscache_volume *volume,
357 			enum fscache_volume_trace where);
358 bool fscache_begin_volume_access(struct fscache_volume *volume,
359 				 struct fscache_cookie *cookie,
360 				 enum fscache_access_trace why);
361 void fscache_create_volume(struct fscache_volume *volume, bool wait);
362 
363 /*****************************************************************************/
364 /*
365  * debug tracing
366  */
367 #define dbgprintk(FMT, ...) \
368 	printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
369 
370 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
371 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
372 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
373 
374 #ifdef __KDEBUG
375 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
376 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
377 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
378 
379 #elif defined(CONFIG_NETFS_DEBUG)
380 #define _enter(FMT, ...)			\
381 do {						\
382 	if (netfs_debug)			\
383 		kenter(FMT, ##__VA_ARGS__);	\
384 } while (0)
385 
386 #define _leave(FMT, ...)			\
387 do {						\
388 	if (netfs_debug)			\
389 		kleave(FMT, ##__VA_ARGS__);	\
390 } while (0)
391 
392 #define _debug(FMT, ...)			\
393 do {						\
394 	if (netfs_debug)			\
395 		kdebug(FMT, ##__VA_ARGS__);	\
396 } while (0)
397 
398 #else
399 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
400 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
401 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
402 #endif
403 
404 /*
405  * assertions
406  */
407 #if 1 /* defined(__KDEBUGALL) */
408 
409 #define ASSERT(X)							\
410 do {									\
411 	if (unlikely(!(X))) {						\
412 		pr_err("\n");					\
413 		pr_err("Assertion failed\n");	\
414 		BUG();							\
415 	}								\
416 } while (0)
417 
418 #define ASSERTCMP(X, OP, Y)						\
419 do {									\
420 	if (unlikely(!((X) OP (Y)))) {					\
421 		pr_err("\n");					\
422 		pr_err("Assertion failed\n");	\
423 		pr_err("%lx " #OP " %lx is false\n",		\
424 		       (unsigned long)(X), (unsigned long)(Y));		\
425 		BUG();							\
426 	}								\
427 } while (0)
428 
429 #define ASSERTIF(C, X)							\
430 do {									\
431 	if (unlikely((C) && !(X))) {					\
432 		pr_err("\n");					\
433 		pr_err("Assertion failed\n");	\
434 		BUG();							\
435 	}								\
436 } while (0)
437 
438 #define ASSERTIFCMP(C, X, OP, Y)					\
439 do {									\
440 	if (unlikely((C) && !((X) OP (Y)))) {				\
441 		pr_err("\n");					\
442 		pr_err("Assertion failed\n");	\
443 		pr_err("%lx " #OP " %lx is false\n",		\
444 		       (unsigned long)(X), (unsigned long)(Y));		\
445 		BUG();							\
446 	}								\
447 } while (0)
448 
449 #else
450 
451 #define ASSERT(X)			do {} while (0)
452 #define ASSERTCMP(X, OP, Y)		do {} while (0)
453 #define ASSERTIF(C, X)			do {} while (0)
454 #define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)
455 
456 #endif /* assert or not */
457