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