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 void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error);
27 int netfs_prefetch_for_write(struct file *file, struct folio *folio,
28 size_t offset, size_t len);
29
30 /*
31 * buffered_write.c
32 */
33 void netfs_update_i_size(struct netfs_inode *ctx, struct inode *inode,
34 loff_t pos, size_t copied);
35
36 /*
37 * main.c
38 */
39 extern unsigned int netfs_debug;
40 extern struct list_head netfs_io_requests;
41 extern spinlock_t netfs_proc_lock;
42 extern mempool_t netfs_request_pool;
43 extern mempool_t netfs_subrequest_pool;
44
45 #ifdef CONFIG_PROC_FS
netfs_proc_add_rreq(struct netfs_io_request * rreq)46 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq)
47 {
48 spin_lock(&netfs_proc_lock);
49 list_add_tail_rcu(&rreq->proc_link, &netfs_io_requests);
50 spin_unlock(&netfs_proc_lock);
51 }
netfs_proc_del_rreq(struct netfs_io_request * rreq)52 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq)
53 {
54 if (!list_empty(&rreq->proc_link)) {
55 spin_lock(&netfs_proc_lock);
56 list_del_rcu(&rreq->proc_link);
57 spin_unlock(&netfs_proc_lock);
58 }
59 }
60 #else
netfs_proc_add_rreq(struct netfs_io_request * rreq)61 static inline void netfs_proc_add_rreq(struct netfs_io_request *rreq) {}
netfs_proc_del_rreq(struct netfs_io_request * rreq)62 static inline void netfs_proc_del_rreq(struct netfs_io_request *rreq) {}
63 #endif
64
65 /*
66 * misc.c
67 */
68 struct folio_queue *netfs_buffer_make_space(struct netfs_io_request *rreq,
69 enum netfs_folioq_trace trace);
70 void netfs_reset_iter(struct netfs_io_subrequest *subreq);
71 void netfs_wake_collector(struct netfs_io_request *rreq);
72 void netfs_subreq_clear_in_progress(struct netfs_io_subrequest *subreq);
73 void netfs_wait_for_in_progress_stream(struct netfs_io_request *rreq,
74 struct netfs_io_stream *stream);
75 ssize_t netfs_wait_for_read(struct netfs_io_request *rreq);
76 ssize_t netfs_wait_for_write(struct netfs_io_request *rreq);
77 void netfs_wait_for_paused_read(struct netfs_io_request *rreq);
78 void netfs_wait_for_paused_write(struct netfs_io_request *rreq);
79
80 /*
81 * objects.c
82 */
83 struct netfs_io_request *netfs_alloc_request(struct address_space *mapping,
84 struct file *file,
85 loff_t start, size_t len,
86 enum netfs_io_origin origin);
87 void netfs_get_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what);
88 void netfs_clear_subrequests(struct netfs_io_request *rreq);
89 void netfs_put_request(struct netfs_io_request *rreq, enum netfs_rreq_ref_trace what);
90 struct netfs_io_subrequest *netfs_alloc_subrequest(struct netfs_io_request *rreq);
91
netfs_see_request(struct netfs_io_request * rreq,enum netfs_rreq_ref_trace what)92 static inline void netfs_see_request(struct netfs_io_request *rreq,
93 enum netfs_rreq_ref_trace what)
94 {
95 trace_netfs_rreq_ref(rreq->debug_id, refcount_read(&rreq->ref), what);
96 }
97
netfs_see_subrequest(struct netfs_io_subrequest * subreq,enum netfs_sreq_ref_trace what)98 static inline void netfs_see_subrequest(struct netfs_io_subrequest *subreq,
99 enum netfs_sreq_ref_trace what)
100 {
101 trace_netfs_sreq_ref(subreq->rreq->debug_id, subreq->debug_index,
102 refcount_read(&subreq->ref), what);
103 }
104
105 /*
106 * read_collect.c
107 */
108 bool netfs_read_collection(struct netfs_io_request *rreq);
109 void netfs_read_collection_worker(struct work_struct *work);
110 void netfs_cache_read_terminated(void *priv, ssize_t transferred_or_error);
111
112 /*
113 * read_pgpriv2.c
114 */
115 void netfs_pgpriv2_copy_to_cache(struct netfs_io_request *rreq, struct folio *folio);
116 void netfs_pgpriv2_end_copy_to_cache(struct netfs_io_request *rreq);
117 bool netfs_pgpriv2_unlock_copied_folios(struct netfs_io_request *wreq);
118
119 /*
120 * read_retry.c
121 */
122 void netfs_retry_reads(struct netfs_io_request *rreq);
123 void netfs_unlock_abandoned_read_pages(struct netfs_io_request *rreq);
124
125 /*
126 * stats.c
127 */
128 #ifdef CONFIG_NETFS_STATS
129 extern atomic_t netfs_n_rh_dio_read;
130 extern atomic_t netfs_n_rh_readahead;
131 extern atomic_t netfs_n_rh_read_folio;
132 extern atomic_t netfs_n_rh_read_single;
133 extern atomic_t netfs_n_rh_rreq;
134 extern atomic_t netfs_n_rh_sreq;
135 extern atomic_t netfs_n_rh_download;
136 extern atomic_t netfs_n_rh_download_done;
137 extern atomic_t netfs_n_rh_download_failed;
138 extern atomic_t netfs_n_rh_download_instead;
139 extern atomic_t netfs_n_rh_read;
140 extern atomic_t netfs_n_rh_read_done;
141 extern atomic_t netfs_n_rh_read_failed;
142 extern atomic_t netfs_n_rh_zero;
143 extern atomic_t netfs_n_rh_short_read;
144 extern atomic_t netfs_n_rh_write;
145 extern atomic_t netfs_n_rh_write_begin;
146 extern atomic_t netfs_n_rh_write_done;
147 extern atomic_t netfs_n_rh_write_failed;
148 extern atomic_t netfs_n_rh_write_zskip;
149 extern atomic_t netfs_n_rh_retry_read_req;
150 extern atomic_t netfs_n_rh_retry_read_subreq;
151 extern atomic_t netfs_n_wh_buffered_write;
152 extern atomic_t netfs_n_wh_writethrough;
153 extern atomic_t netfs_n_wh_dio_write;
154 extern atomic_t netfs_n_wh_writepages;
155 extern atomic_t netfs_n_wh_copy_to_cache;
156 extern atomic_t netfs_n_wh_wstream_conflict;
157 extern atomic_t netfs_n_wh_upload;
158 extern atomic_t netfs_n_wh_upload_done;
159 extern atomic_t netfs_n_wh_upload_failed;
160 extern atomic_t netfs_n_wh_write;
161 extern atomic_t netfs_n_wh_write_done;
162 extern atomic_t netfs_n_wh_write_failed;
163 extern atomic_t netfs_n_wh_retry_write_req;
164 extern atomic_t netfs_n_wh_retry_write_subreq;
165 extern atomic_t netfs_n_wb_lock_skip;
166 extern atomic_t netfs_n_wb_lock_wait;
167 extern atomic_t netfs_n_folioq;
168
169 int netfs_stats_show(struct seq_file *m, void *v);
170
netfs_stat(atomic_t * stat)171 static inline void netfs_stat(atomic_t *stat)
172 {
173 atomic_inc(stat);
174 }
175
netfs_stat_d(atomic_t * stat)176 static inline void netfs_stat_d(atomic_t *stat)
177 {
178 atomic_dec(stat);
179 }
180
181 #else
182 #define netfs_stat(x) do {} while(0)
183 #define netfs_stat_d(x) do {} while(0)
184 #endif
185
186 /*
187 * write_collect.c
188 */
189 int netfs_folio_written_back(struct folio *folio);
190 bool netfs_write_collection(struct netfs_io_request *wreq);
191 void netfs_write_collection_worker(struct work_struct *work);
192
193 /*
194 * write_issue.c
195 */
196 struct netfs_io_request *netfs_create_write_req(struct address_space *mapping,
197 struct file *file,
198 loff_t start,
199 enum netfs_io_origin origin);
200 void netfs_reissue_write(struct netfs_io_stream *stream,
201 struct netfs_io_subrequest *subreq,
202 struct iov_iter *source);
203 void netfs_issue_write(struct netfs_io_request *wreq,
204 struct netfs_io_stream *stream);
205 size_t netfs_advance_write(struct netfs_io_request *wreq,
206 struct netfs_io_stream *stream,
207 loff_t start, size_t len, bool to_eof);
208 struct netfs_io_request *netfs_begin_writethrough(struct kiocb *iocb, size_t len);
209 int netfs_advance_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc,
210 struct folio *folio, size_t copied, bool to_page_end,
211 struct folio **writethrough_cache);
212 ssize_t netfs_end_writethrough(struct netfs_io_request *wreq, struct writeback_control *wbc,
213 struct folio *writethrough_cache);
214 int netfs_unbuffered_write(struct netfs_io_request *wreq, bool may_wait, size_t len);
215
216 /*
217 * write_retry.c
218 */
219 void netfs_retry_writes(struct netfs_io_request *wreq);
220
221 /*
222 * Miscellaneous functions.
223 */
netfs_is_cache_enabled(struct netfs_inode * ctx)224 static inline bool netfs_is_cache_enabled(struct netfs_inode *ctx)
225 {
226 #if IS_ENABLED(CONFIG_FSCACHE)
227 struct fscache_cookie *cookie = ctx->cache;
228
229 return fscache_cookie_valid(cookie) && cookie->cache_priv &&
230 fscache_cookie_enabled(cookie);
231 #else
232 return false;
233 #endif
234 }
235
236 /*
237 * Get a ref on a netfs group attached to a dirty page (e.g. a ceph snap).
238 */
netfs_get_group(struct netfs_group * netfs_group)239 static inline struct netfs_group *netfs_get_group(struct netfs_group *netfs_group)
240 {
241 if (netfs_group && netfs_group != NETFS_FOLIO_COPY_TO_CACHE)
242 refcount_inc(&netfs_group->ref);
243 return netfs_group;
244 }
245
246 /*
247 * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
248 */
netfs_put_group(struct netfs_group * netfs_group)249 static inline void netfs_put_group(struct netfs_group *netfs_group)
250 {
251 if (netfs_group &&
252 netfs_group != NETFS_FOLIO_COPY_TO_CACHE &&
253 refcount_dec_and_test(&netfs_group->ref))
254 netfs_group->free(netfs_group);
255 }
256
257 /*
258 * Dispose of a netfs group attached to a dirty page (e.g. a ceph snap).
259 */
netfs_put_group_many(struct netfs_group * netfs_group,int nr)260 static inline void netfs_put_group_many(struct netfs_group *netfs_group, int nr)
261 {
262 if (netfs_group &&
263 netfs_group != NETFS_FOLIO_COPY_TO_CACHE &&
264 refcount_sub_and_test(nr, &netfs_group->ref))
265 netfs_group->free(netfs_group);
266 }
267
268 /*
269 * Clear and wake up a NETFS_RREQ_* flag bit on a request.
270 */
netfs_wake_rreq_flag(struct netfs_io_request * rreq,unsigned int rreq_flag,enum netfs_rreq_trace trace)271 static inline void netfs_wake_rreq_flag(struct netfs_io_request *rreq,
272 unsigned int rreq_flag,
273 enum netfs_rreq_trace trace)
274 {
275 if (test_bit(rreq_flag, &rreq->flags)) {
276 clear_bit_unlock(rreq_flag, &rreq->flags);
277 smp_mb__after_atomic(); /* Set flag before task state */
278 trace_netfs_rreq(rreq, trace);
279 wake_up(&rreq->waitq);
280 }
281 }
282
283 /*
284 * Test the NETFS_RREQ_IN_PROGRESS flag, inserting an appropriate barrier.
285 */
netfs_check_rreq_in_progress(const struct netfs_io_request * rreq)286 static inline bool netfs_check_rreq_in_progress(const struct netfs_io_request *rreq)
287 {
288 /* Order read of flags before read of anything else, such as error. */
289 return test_bit_acquire(NETFS_RREQ_IN_PROGRESS, &rreq->flags);
290 }
291
292 /*
293 * Test the NETFS_SREQ_IN_PROGRESS flag, inserting an appropriate barrier.
294 */
netfs_check_subreq_in_progress(const struct netfs_io_subrequest * subreq)295 static inline bool netfs_check_subreq_in_progress(const struct netfs_io_subrequest *subreq)
296 {
297 /* Order read of flags before read of anything else, such as error. */
298 return test_bit_acquire(NETFS_SREQ_IN_PROGRESS, &subreq->flags);
299 }
300
301 /*
302 * fscache-cache.c
303 */
304 #ifdef CONFIG_PROC_FS
305 extern const struct seq_operations fscache_caches_seq_ops;
306 #endif
307 bool fscache_begin_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
308 void fscache_end_cache_access(struct fscache_cache *cache, enum fscache_access_trace why);
309 struct fscache_cache *fscache_lookup_cache(const char *name, bool is_cache);
310 void fscache_put_cache(struct fscache_cache *cache, enum fscache_cache_trace where);
311
fscache_cache_state(const struct fscache_cache * cache)312 static inline enum fscache_cache_state fscache_cache_state(const struct fscache_cache *cache)
313 {
314 return smp_load_acquire(&cache->state);
315 }
316
fscache_cache_is_live(const struct fscache_cache * cache)317 static inline bool fscache_cache_is_live(const struct fscache_cache *cache)
318 {
319 return fscache_cache_state(cache) == FSCACHE_CACHE_IS_ACTIVE;
320 }
321
fscache_set_cache_state(struct fscache_cache * cache,enum fscache_cache_state new_state)322 static inline void fscache_set_cache_state(struct fscache_cache *cache,
323 enum fscache_cache_state new_state)
324 {
325 smp_store_release(&cache->state, new_state);
326
327 }
328
fscache_set_cache_state_maybe(struct fscache_cache * cache,enum fscache_cache_state old_state,enum fscache_cache_state new_state)329 static inline bool fscache_set_cache_state_maybe(struct fscache_cache *cache,
330 enum fscache_cache_state old_state,
331 enum fscache_cache_state new_state)
332 {
333 return try_cmpxchg_release(&cache->state, &old_state, new_state);
334 }
335
336 /*
337 * fscache-cookie.c
338 */
339 extern struct kmem_cache *fscache_cookie_jar;
340 #ifdef CONFIG_PROC_FS
341 extern const struct seq_operations fscache_cookies_seq_ops;
342 #endif
343 extern struct timer_list fscache_cookie_lru_timer;
344
345 extern void fscache_print_cookie(struct fscache_cookie *cookie, char prefix);
346 extern bool fscache_begin_cookie_access(struct fscache_cookie *cookie,
347 enum fscache_access_trace why);
348
fscache_see_cookie(struct fscache_cookie * cookie,enum fscache_cookie_trace where)349 static inline void fscache_see_cookie(struct fscache_cookie *cookie,
350 enum fscache_cookie_trace where)
351 {
352 trace_fscache_cookie(cookie->debug_id, refcount_read(&cookie->ref),
353 where);
354 }
355
356 /*
357 * fscache-main.c
358 */
359 extern unsigned int fscache_hash(unsigned int salt, const void *data, size_t len);
360 #ifdef CONFIG_FSCACHE
361 int __init fscache_init(void);
362 void __exit fscache_exit(void);
363 #else
fscache_init(void)364 static inline int fscache_init(void) { return 0; }
fscache_exit(void)365 static inline void fscache_exit(void) {}
366 #endif
367
368 /*
369 * fscache-proc.c
370 */
371 #ifdef CONFIG_PROC_FS
372 extern int __init fscache_proc_init(void);
373 extern void fscache_proc_cleanup(void);
374 #else
375 #define fscache_proc_init() (0)
376 #define fscache_proc_cleanup() do {} while (0)
377 #endif
378
379 /*
380 * fscache-stats.c
381 */
382 #ifdef CONFIG_FSCACHE_STATS
383 extern atomic_t fscache_n_volumes;
384 extern atomic_t fscache_n_volumes_collision;
385 extern atomic_t fscache_n_volumes_nomem;
386 extern atomic_t fscache_n_cookies;
387 extern atomic_t fscache_n_cookies_lru;
388 extern atomic_t fscache_n_cookies_lru_expired;
389 extern atomic_t fscache_n_cookies_lru_removed;
390 extern atomic_t fscache_n_cookies_lru_dropped;
391
392 extern atomic_t fscache_n_acquires;
393 extern atomic_t fscache_n_acquires_ok;
394 extern atomic_t fscache_n_acquires_oom;
395
396 extern atomic_t fscache_n_invalidates;
397
398 extern atomic_t fscache_n_relinquishes;
399 extern atomic_t fscache_n_relinquishes_retire;
400 extern atomic_t fscache_n_relinquishes_dropped;
401
402 extern atomic_t fscache_n_resizes;
403 extern atomic_t fscache_n_resizes_null;
404
fscache_stat(atomic_t * stat)405 static inline void fscache_stat(atomic_t *stat)
406 {
407 atomic_inc(stat);
408 }
409
fscache_stat_d(atomic_t * stat)410 static inline void fscache_stat_d(atomic_t *stat)
411 {
412 atomic_dec(stat);
413 }
414
415 #define __fscache_stat(stat) (stat)
416
417 int fscache_stats_show(struct seq_file *m);
418 #else
419
420 #define __fscache_stat(stat) (NULL)
421 #define fscache_stat(stat) do {} while (0)
422 #define fscache_stat_d(stat) do {} while (0)
423
fscache_stats_show(struct seq_file * m)424 static inline int fscache_stats_show(struct seq_file *m) { return 0; }
425 #endif
426
427 /*
428 * fscache-volume.c
429 */
430 #ifdef CONFIG_PROC_FS
431 extern const struct seq_operations fscache_volumes_seq_ops;
432 #endif
433
434 struct fscache_volume *fscache_get_volume(struct fscache_volume *volume,
435 enum fscache_volume_trace where);
436 bool fscache_begin_volume_access(struct fscache_volume *volume,
437 struct fscache_cookie *cookie,
438 enum fscache_access_trace why);
439 void fscache_create_volume(struct fscache_volume *volume, bool wait);
440
441 /*****************************************************************************/
442 /*
443 * debug tracing
444 */
445 #define dbgprintk(FMT, ...) \
446 printk("[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
447
448 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
449 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
450 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
451
452 #ifdef __KDEBUG
453 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
454 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
455 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
456
457 #elif defined(CONFIG_NETFS_DEBUG)
458 #define _enter(FMT, ...) \
459 do { \
460 if (netfs_debug) \
461 kenter(FMT, ##__VA_ARGS__); \
462 } while (0)
463
464 #define _leave(FMT, ...) \
465 do { \
466 if (netfs_debug) \
467 kleave(FMT, ##__VA_ARGS__); \
468 } while (0)
469
470 #define _debug(FMT, ...) \
471 do { \
472 if (netfs_debug) \
473 kdebug(FMT, ##__VA_ARGS__); \
474 } while (0)
475
476 #else
477 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
478 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
479 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
480 #endif
481
482 /*
483 * assertions
484 */
485 #if 1 /* defined(__KDEBUGALL) */
486
487 #define ASSERT(X) \
488 do { \
489 if (unlikely(!(X))) { \
490 pr_err("\n"); \
491 pr_err("Assertion failed\n"); \
492 BUG(); \
493 } \
494 } while (0)
495
496 #define ASSERTCMP(X, OP, Y) \
497 do { \
498 if (unlikely(!((X) OP (Y)))) { \
499 pr_err("\n"); \
500 pr_err("Assertion failed\n"); \
501 pr_err("%lx " #OP " %lx is false\n", \
502 (unsigned long)(X), (unsigned long)(Y)); \
503 BUG(); \
504 } \
505 } while (0)
506
507 #define ASSERTIF(C, X) \
508 do { \
509 if (unlikely((C) && !(X))) { \
510 pr_err("\n"); \
511 pr_err("Assertion failed\n"); \
512 BUG(); \
513 } \
514 } while (0)
515
516 #define ASSERTIFCMP(C, X, OP, Y) \
517 do { \
518 if (unlikely((C) && !((X) OP (Y)))) { \
519 pr_err("\n"); \
520 pr_err("Assertion failed\n"); \
521 pr_err("%lx " #OP " %lx is false\n", \
522 (unsigned long)(X), (unsigned long)(Y)); \
523 BUG(); \
524 } \
525 } while (0)
526
527 #else
528
529 #define ASSERT(X) do {} while (0)
530 #define ASSERTCMP(X, OP, Y) do {} while (0)
531 #define ASSERTIF(C, X) do {} while (0)
532 #define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
533
534 #endif /* assert or not */
535