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