xref: /linux/fs/netfs/internal.h (revision 570172569238c66a482ec3eb5d766cc9cf255f69)
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/folio_queue.h>
11 #include <linux/netfs.h>
12 #include <linux/fscache.h>
13 #include <linux/fscache-cache.h>
14 #include <trace/events/netfs.h>
15 #include <trace/events/fscache.h>
16 
17 #ifdef pr_fmt
18 #undef pr_fmt
19 #endif
20 
21 #define pr_fmt(fmt) "netfs: " fmt
22 
23 /*
24  * buffered_read.c
25  */
26 int netfs_prefetch_for_write(struct file *file, struct folio *folio,
27 			     size_t offset, size_t len);
28 
29 /*
30  * main.c
31  */
32 extern unsigned int netfs_debug;
33 extern struct list_head netfs_io_requests;
34 extern spinlock_t netfs_proc_lock;
35 extern mempool_t netfs_request_pool;
36 extern mempool_t netfs_subrequest_pool;
37 
38 #ifdef CONFIG_PROC_FS
39 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq)
40 {
41 	spin_lock(&netfs_proc_lock);
42 	list_add_tail_rcu(&rreq->proc_link, &netfs_io_requests);
43 	spin_unlock(&netfs_proc_lock);
44 }
45 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq)
46 {
47 	if (!list_empty(&rreq->proc_link)) {
48 		spin_lock(&netfs_proc_lock);
49 		list_del_rcu(&rreq->proc_link);
50 		spin_unlock(&netfs_proc_lock);
51 	}
52 }
53 #else
54 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) {}
55 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq) {}
56 #endif
57 
58 /*
59  * misc.c
60  */
61 int netfs_buffer_append_folio(struct netfs_io_request *rreq, struct folio *folio,
62 			      bool needs_put);
63 struct folio_queue *netfs_delete_buffer_head(struct netfs_io_request *wreq);
64 void netfs_clear_buffer(struct netfs_io_request *rreq);
65 void netfs_reset_iter(struct netfs_io_subrequest *subreq);
66 
67 /*
68  * objects.c
69  */
70 struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
71 					     struct file *file,
72 					     loff_t start, size_t len,
73 					     enum netfs_io_origin origin);
74 void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what);
75 void netfs_clear_subrequests(struct netfs_io_request *rreq, bool was_async);
76 void netfs_put_request(struct netfs_io_request *rreq, bool was_async,
77 		       enum netfs_rreq_ref_trace what);
78 struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq);
79 
80 static inline void netfs_see_request(struct netfs_io_request *rreq,
81 				     enum netfs_rreq_ref_trace what)
82 {
83 	trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what);
84 }
85 
86 /*
87  * read_collect.c
88  */
89 void netfs_read_termination_worker(struct work_struct *work);
90 void netfs_rreq_terminated(struct netfs_io_request *rreq, bool was_async);
91 
92 /*
93  * read_pgpriv2.c
94  */
95 void netfs_pgpriv2_mark_copy_to_cache(struct netfs_io_subrequest *subreq,
96 				      struct netfs_io_request *rreq,
97 				      struct folio_queue *folioq,
98 				      int slot);
99 void netfs_pgpriv2_write_to_the_cache(struct netfs_io_request *rreq);
100 bool netfs_pgpriv2_unlock_copied_folios(struct netfs_io_request *wreq);
101 
102 /*
103  * read_retry.c
104  */
105 void netfs_retry_reads(struct netfs_io_request *rreq);
106 void netfs_unlock_abandoned_read_pages(struct netfs_io_request *rreq);
107 
108 /*
109  * stats.c
110  */
111 #ifdef CONFIG_NETFS_STATS
112 extern atomic_t netfs_n_rh_dio_read;
113 extern atomic_t netfs_n_rh_readahead;
114 extern atomic_t netfs_n_rh_read_folio;
115 extern atomic_t netfs_n_rh_rreq;
116 extern atomic_t netfs_n_rh_sreq;
117 extern atomic_t netfs_n_rh_download;
118 extern atomic_t netfs_n_rh_download_done;
119 extern atomic_t netfs_n_rh_download_failed;
120 extern atomic_t netfs_n_rh_download_instead;
121 extern atomic_t netfs_n_rh_read;
122 extern atomic_t netfs_n_rh_read_done;
123 extern atomic_t netfs_n_rh_read_failed;
124 extern atomic_t netfs_n_rh_zero;
125 extern atomic_t netfs_n_rh_short_read;
126 extern atomic_t netfs_n_rh_write;
127 extern atomic_t netfs_n_rh_write_begin;
128 extern atomic_t netfs_n_rh_write_done;
129 extern atomic_t netfs_n_rh_write_failed;
130 extern atomic_t netfs_n_rh_write_zskip;
131 extern atomic_t netfs_n_wh_buffered_write;
132 extern atomic_t netfs_n_wh_writethrough;
133 extern atomic_t netfs_n_wh_dio_write;
134 extern atomic_t netfs_n_wh_writepages;
135 extern atomic_t netfs_n_wh_copy_to_cache;
136 extern atomic_t netfs_n_wh_wstream_conflict;
137 extern atomic_t netfs_n_wh_upload;
138 extern atomic_t netfs_n_wh_upload_done;
139 extern atomic_t netfs_n_wh_upload_failed;
140 extern atomic_t netfs_n_wh_write;
141 extern atomic_t netfs_n_wh_write_done;
142 extern atomic_t netfs_n_wh_write_failed;
143 extern atomic_t netfs_n_wb_lock_skip;
144 extern atomic_t netfs_n_wb_lock_wait;
145 extern atomic_t netfs_n_folioq;
146 
147 int netfs_stats_show(struct seq_file *m, void *v);
148 
149 static inline void netfs_stat(atomic_t *stat)
150 {
151 	atomic_inc(stat);
152 }
153 
154 static inline void netfs_stat_d(atomic_t *stat)
155 {
156 	atomic_dec(stat);
157 }
158 
159 #else
160 #define netfs_stat(x) do {} while(0)
161 #define netfs_stat_d(x) do {} while(0)
162 #endif
163 
164 /*
165  * write_collect.c
166  */
167 int netfs_folio_written_back(struct folio *folio);
168 void netfs_write_collection_worker(struct work_struct *work);
169 void netfs_wake_write_collector(struct netfs_io_request *wreq, bool was_async);
170 
171 /*
172  * write_issue.c
173  */
174 struct netfs_io_request *netfs_create_write_req(struct address_space *mapping,
175 						struct file *file,
176 						loff_t start,
177 						enum netfs_io_origin origin);
178 void netfs_reissue_write(struct netfs_io_stream *stream,
179 			 struct netfs_io_subrequest *subreq,
180 			 struct iov_iter *source);
181 void netfs_issue_write(struct netfs_io_request *wreq,
182 		       struct netfs_io_stream *stream);
183 int netfs_advance_write(struct netfs_io_request *wreq,
184 			struct netfs_io_stream *stream,
185 			loff_t start, size_t len, bool to_eof);
186 struct netfs_io_request *netfs_begin_writethrough(struct kiocb *iocb, size_t len);
187 int netfs_advance_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc,
188 			       struct folio *folio, size_t copied, bool to_page_end,
189 			       struct folio **writethrough_cache);
190 int netfs_end_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc,
191 			   struct folio *writethrough_cache);
192 int netfs_unbuffered_write(struct netfs_io_request *wreq, bool may_wait, size_t len);
193 
194 /*
195  * Miscellaneous functions.
196  */
197 static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
198 {
199 #if IS_ENABLED(CONFIG_FSCACHE)
200 	struct fscache_cookie *cookie = ctx->cache;
201 
202 	return fscache_cookie_valid(cookie) && cookie->cache_priv &&
203 		fscache_cookie_enabled(cookie);
204 #else
205 	return false;
206 #endif
207 }
208 
209 /*
210  * Get a ref on a netfs group attached to a dirty page (e.g. a ceph snap).
211  */
212 static inline struct netfs_group *netfs_get_group(struct netfs_group *netfs_group)
213 {
214 	if (netfs_group && netfs_group != NETFS_FOLIO_COPY_TO_CACHE)
215 		refcount_inc(&netfs_group->ref);
216 	return netfs_group;
217 }
218 
219 /*
220  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
221  */
222 static inline void netfs_put_group(struct netfs_group *netfs_group)
223 {
224 	if (netfs_group &&
225 	    netfs_group != NETFS_FOLIO_COPY_TO_CACHE &&
226 	    refcount_dec_and_test(&netfs_group->ref))
227 		netfs_group->free(netfs_group);
228 }
229 
230 /*
231  * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
232  */
233 static inline void netfs_put_group_many(struct netfs_group *netfs_group, int nr)
234 {
235 	if (netfs_group &&
236 	    netfs_group != NETFS_FOLIO_COPY_TO_CACHE &&
237 	    refcount_sub_and_test(nr, &netfs_group->ref))
238 		netfs_group->free(netfs_group);
239 }
240 
241 /*
242  * fscache-cache.c
243  */
244 #ifdef CONFIG_PROC_FS
245 extern const struct seq_operations fscache_caches_seq_ops;
246 #endif
247 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
248 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
249 struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
250 void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
251 
252 static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
253 {
254 	return smp_load_acquire(&cache->state);
255 }
256 
257 static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
258 {
259 	return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
260 }
261 
262 static inline void fscache_set_cache_state(struct fscache_cache *cache,
263 					   enum fscache_cache_state new_state)
264 {
265 	smp_store_release(&cache->state, new_state);
266 
267 }
268 
269 static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
270 						 enum fscache_cache_state old_state,
271 						 enum fscache_cache_state new_state)
272 {
273 	return try_cmpxchg_release(&cache->state, &old_state, new_state);
274 }
275 
276 /*
277  * fscache-cookie.c
278  */
279 extern struct kmem_cache *fscache_cookie_jar;
280 #ifdef CONFIG_PROC_FS
281 extern const struct seq_operations fscache_cookies_seq_ops;
282 #endif
283 extern struct timer_list fscache_cookie_lru_timer;
284 
285 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
286 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
287 					enum fscache_access_trace why);
288 
289 static inline void fscache_see_cookie(struct fscache_cookie *cookie,
290 				      enum fscache_cookie_trace where)
291 {
292 	trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
293 			     where);
294 }
295 
296 /*
297  * fscache-main.c
298  */
299 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
300 #ifdef CONFIG_FSCACHE
301 int __init fscache_init(void);
302 void __exit fscache_exit(void);
303 #else
304 static inline int fscache_init(void) { return 0; }
305 static inline void fscache_exit(void) {}
306 #endif
307 
308 /*
309  * fscache-proc.c
310  */
311 #ifdef CONFIG_PROC_FS
312 extern int __init fscache_proc_init(void);
313 extern void fscache_proc_cleanup(void);
314 #else
315 #define fscache_proc_init()	(0)
316 #define fscache_proc_cleanup()	do {} while (0)
317 #endif
318 
319 /*
320  * fscache-stats.c
321  */
322 #ifdef CONFIG_FSCACHE_STATS
323 extern atomic_t fscache_n_volumes;
324 extern atomic_t fscache_n_volumes_collision;
325 extern atomic_t fscache_n_volumes_nomem;
326 extern atomic_t fscache_n_cookies;
327 extern atomic_t fscache_n_cookies_lru;
328 extern atomic_t fscache_n_cookies_lru_expired;
329 extern atomic_t fscache_n_cookies_lru_removed;
330 extern atomic_t fscache_n_cookies_lru_dropped;
331 
332 extern atomic_t fscache_n_acquires;
333 extern atomic_t fscache_n_acquires_ok;
334 extern atomic_t fscache_n_acquires_oom;
335 
336 extern atomic_t fscache_n_invalidates;
337 
338 extern atomic_t fscache_n_relinquishes;
339 extern atomic_t fscache_n_relinquishes_retire;
340 extern atomic_t fscache_n_relinquishes_dropped;
341 
342 extern atomic_t fscache_n_resizes;
343 extern atomic_t fscache_n_resizes_null;
344 
345 static inline void fscache_stat(atomic_t *stat)
346 {
347 	atomic_inc(stat);
348 }
349 
350 static inline void fscache_stat_d(atomic_t *stat)
351 {
352 	atomic_dec(stat);
353 }
354 
355 #define __fscache_stat(stat) (stat)
356 
357 int fscache_stats_show(struct seq_file *m);
358 #else
359 
360 #define __fscache_stat(stat) (NULL)
361 #define fscache_stat(stat) do {} while (0)
362 #define fscache_stat_d(stat) do {} while (0)
363 
364 static inline int fscache_stats_show(struct seq_file *m) { return 0; }
365 #endif
366 
367 /*
368  * fscache-volume.c
369  */
370 #ifdef CONFIG_PROC_FS
371 extern const struct seq_operations fscache_volumes_seq_ops;
372 #endif
373 
374 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
375 					  enum fscache_volume_trace where);
376 bool fscache_begin_volume_access(struct fscache_volume *volume,
377 				 struct fscache_cookie *cookie,
378 				 enum fscache_access_trace why);
379 void fscache_create_volume(struct fscache_volume *volume, bool wait);
380 
381 /*****************************************************************************/
382 /*
383  * debug tracing
384  */
385 #define dbgprintk(FMT, ...) \
386 	printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
387 
388 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
389 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
390 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
391 
392 #ifdef __KDEBUG
393 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
394 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
395 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
396 
397 #elif defined(CONFIG_NETFS_DEBUG)
398 #define _enter(FMT, ...)			\
399 do {						\
400 	if (netfs_debug)			\
401 		kenter(FMT, ##__VA_ARGS__);	\
402 } while (0)
403 
404 #define _leave(FMT, ...)			\
405 do {						\
406 	if (netfs_debug)			\
407 		kleave(FMT, ##__VA_ARGS__);	\
408 } while (0)
409 
410 #define _debug(FMT, ...)			\
411 do {						\
412 	if (netfs_debug)			\
413 		kdebug(FMT, ##__VA_ARGS__);	\
414 } while (0)
415 
416 #else
417 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
418 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
419 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
420 #endif
421 
422 /*
423  * assertions
424  */
425 #if 1 /* defined(__KDEBUGALL) */
426 
427 #define ASSERT(X)							\
428 do {									\
429 	if (unlikely(!(X))) {						\
430 		pr_err("\n");					\
431 		pr_err("Assertion failed\n");	\
432 		BUG();							\
433 	}								\
434 } while (0)
435 
436 #define ASSERTCMP(X, OP, Y)						\
437 do {									\
438 	if (unlikely(!((X) OP (Y)))) {					\
439 		pr_err("\n");					\
440 		pr_err("Assertion failed\n");	\
441 		pr_err("%lx " #OP " %lx is false\n",		\
442 		       (unsigned long)(X), (unsigned long)(Y));		\
443 		BUG();							\
444 	}								\
445 } while (0)
446 
447 #define ASSERTIF(C, X)							\
448 do {									\
449 	if (unlikely((C) && !(X))) {					\
450 		pr_err("\n");					\
451 		pr_err("Assertion failed\n");	\
452 		BUG();							\
453 	}								\
454 } while (0)
455 
456 #define ASSERTIFCMP(C, X, OP, Y)					\
457 do {									\
458 	if (unlikely((C) && !((X) OP (Y)))) {				\
459 		pr_err("\n");					\
460 		pr_err("Assertion failed\n");	\
461 		pr_err("%lx " #OP " %lx is false\n",		\
462 		       (unsigned long)(X), (unsigned long)(Y));		\
463 		BUG();							\
464 	}								\
465 } while (0)
466 
467 #else
468 
469 #define ASSERT(X)			do {} while (0)
470 #define ASSERTCMP(X, OP, Y)		do {} while (0)
471 #define ASSERTIF(C, X)			do {} while (0)
472 #define ASSERTIFCMP(C, X, OP, Y)	do {} while (0)
473 
474 #endif /* assert or not */
475