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