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David Howells9ae326a2009-04-03 16:42:41 +01001/* General netfs cache on cache files internal defs
2 *
3 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public Licence
8 * as published by the Free Software Foundation; either version
9 * 2 of the Licence, or (at your option) any later version.
10 */
11
Fabian Frederick0227d6ab2014-06-06 14:37:33 -070012#ifdef pr_fmt
13#undef pr_fmt
14#endif
15
16#define pr_fmt(fmt) "CacheFiles: " fmt
17
18
David Howells9ae326a2009-04-03 16:42:41 +010019#include <linux/fscache-cache.h>
20#include <linux/timer.h>
21#include <linux/wait.h>
22#include <linux/workqueue.h>
23#include <linux/security.h>
24
25struct cachefiles_cache;
26struct cachefiles_object;
27
28extern unsigned cachefiles_debug;
29#define CACHEFILES_DEBUG_KENTER 1
30#define CACHEFILES_DEBUG_KLEAVE 2
31#define CACHEFILES_DEBUG_KDEBUG 4
32
Mel Gorman71baba42015-11-06 16:28:28 -080033#define cachefiles_gfp (__GFP_RECLAIM | __GFP_NORETRY | __GFP_NOMEMALLOC)
David Howells5f4f9f42012-12-20 21:52:33 +000034
David Howells9ae326a2009-04-03 16:42:41 +010035/*
36 * node records
37 */
38struct cachefiles_object {
39 struct fscache_object fscache; /* fscache handle */
40 struct cachefiles_lookup_data *lookup_data; /* cached lookup data */
41 struct dentry *dentry; /* the file/dir representing this object */
42 struct dentry *backer; /* backing file */
43 loff_t i_size; /* object size */
44 unsigned long flags;
45#define CACHEFILES_OBJECT_ACTIVE 0 /* T if marked active */
46 atomic_t usage; /* object usage count */
47 uint8_t type; /* object type */
48 uint8_t new; /* T if object new */
49 spinlock_t work_lock;
50 struct rb_node active_node; /* link in active tree (dentry is key) */
51};
52
53extern struct kmem_cache *cachefiles_object_jar;
54
55/*
56 * Cache files cache definition
57 */
58struct cachefiles_cache {
59 struct fscache_cache cache; /* FS-Cache record */
60 struct vfsmount *mnt; /* mountpoint holding the cache */
61 struct dentry *graveyard; /* directory into which dead objects go */
62 struct file *cachefilesd; /* manager daemon handle */
63 const struct cred *cache_cred; /* security override for accessing cache */
64 struct mutex daemon_mutex; /* command serialisation mutex */
65 wait_queue_head_t daemon_pollwq; /* poll waitqueue for daemon */
66 struct rb_root active_nodes; /* active nodes (can't be culled) */
67 rwlock_t active_lock; /* lock for active_nodes */
68 atomic_t gravecounter; /* graveyard uniquifier */
69 unsigned frun_percent; /* when to stop culling (% files) */
70 unsigned fcull_percent; /* when to start culling (% files) */
71 unsigned fstop_percent; /* when to stop allocating (% files) */
72 unsigned brun_percent; /* when to stop culling (% blocks) */
73 unsigned bcull_percent; /* when to start culling (% blocks) */
74 unsigned bstop_percent; /* when to stop allocating (% blocks) */
75 unsigned bsize; /* cache's block size */
76 unsigned bshift; /* min(ilog2(PAGE_SIZE / bsize), 0) */
77 uint64_t frun; /* when to stop culling */
78 uint64_t fcull; /* when to start culling */
79 uint64_t fstop; /* when to stop allocating */
80 sector_t brun; /* when to stop culling */
81 sector_t bcull; /* when to start culling */
82 sector_t bstop; /* when to stop allocating */
83 unsigned long flags;
84#define CACHEFILES_READY 0 /* T if cache prepared */
85#define CACHEFILES_DEAD 1 /* T if cache dead */
86#define CACHEFILES_CULLING 2 /* T if cull engaged */
87#define CACHEFILES_STATE_CHANGED 3 /* T if state changed (poll trigger) */
88 char *rootdirname; /* name of cache root directory */
89 char *secctx; /* LSM security context */
90 char *tag; /* cache binding tag */
91};
92
93/*
94 * backing file read tracking
95 */
96struct cachefiles_one_read {
97 wait_queue_t monitor; /* link into monitored waitqueue */
98 struct page *back_page; /* backing file page we're waiting for */
99 struct page *netfs_page; /* netfs page we're going to fill */
100 struct fscache_retrieval *op; /* retrieval op covering this */
101 struct list_head op_link; /* link in op's todo list */
102};
103
104/*
105 * backing file write tracking
106 */
107struct cachefiles_one_write {
108 struct page *netfs_page; /* netfs page to copy */
109 struct cachefiles_object *object;
110 struct list_head obj_link; /* link in object's lists */
111 fscache_rw_complete_t end_io_func;
112 void *context;
113};
114
115/*
116 * auxiliary data xattr buffer
117 */
118struct cachefiles_xattr {
119 uint16_t len;
120 uint8_t type;
121 uint8_t data[];
122};
123
124/*
125 * note change of state for daemon
126 */
127static inline void cachefiles_state_changed(struct cachefiles_cache *cache)
128{
129 set_bit(CACHEFILES_STATE_CHANGED, &cache->flags);
130 wake_up_all(&cache->daemon_pollwq);
131}
132
133/*
David Howells911e6902009-05-27 15:46:55 +0100134 * bind.c
David Howells9ae326a2009-04-03 16:42:41 +0100135 */
136extern int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args);
137extern void cachefiles_daemon_unbind(struct cachefiles_cache *cache);
138
139/*
David Howells911e6902009-05-27 15:46:55 +0100140 * daemon.c
David Howells9ae326a2009-04-03 16:42:41 +0100141 */
142extern const struct file_operations cachefiles_daemon_fops;
143
144extern int cachefiles_has_space(struct cachefiles_cache *cache,
145 unsigned fnr, unsigned bnr);
146
147/*
David Howells911e6902009-05-27 15:46:55 +0100148 * interface.c
David Howells9ae326a2009-04-03 16:42:41 +0100149 */
150extern const struct fscache_cache_ops cachefiles_cache_ops;
151
152/*
David Howells911e6902009-05-27 15:46:55 +0100153 * key.c
David Howells9ae326a2009-04-03 16:42:41 +0100154 */
155extern char *cachefiles_cook_key(const u8 *raw, int keylen, uint8_t type);
156
157/*
David Howells911e6902009-05-27 15:46:55 +0100158 * namei.c
David Howells9ae326a2009-04-03 16:42:41 +0100159 */
160extern int cachefiles_delete_object(struct cachefiles_cache *cache,
161 struct cachefiles_object *object);
162extern int cachefiles_walk_to_object(struct cachefiles_object *parent,
163 struct cachefiles_object *object,
164 const char *key,
165 struct cachefiles_xattr *auxdata);
166extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
167 struct dentry *dir,
168 const char *name);
169
170extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir,
171 char *filename);
172
173extern int cachefiles_check_in_use(struct cachefiles_cache *cache,
174 struct dentry *dir, char *filename);
175
176/*
David Howells911e6902009-05-27 15:46:55 +0100177 * proc.c
David Howells9ae326a2009-04-03 16:42:41 +0100178 */
179#ifdef CONFIG_CACHEFILES_HISTOGRAM
180extern atomic_t cachefiles_lookup_histogram[HZ];
181extern atomic_t cachefiles_mkdir_histogram[HZ];
182extern atomic_t cachefiles_create_histogram[HZ];
183
184extern int __init cachefiles_proc_init(void);
185extern void cachefiles_proc_cleanup(void);
186static inline
187void cachefiles_hist(atomic_t histogram[], unsigned long start_jif)
188{
189 unsigned long jif = jiffies - start_jif;
190 if (jif >= HZ)
191 jif = HZ - 1;
192 atomic_inc(&histogram[jif]);
193}
194
195#else
196#define cachefiles_proc_init() (0)
197#define cachefiles_proc_cleanup() do {} while (0)
198#define cachefiles_hist(hist, start_jif) do {} while (0)
199#endif
200
201/*
David Howells911e6902009-05-27 15:46:55 +0100202 * rdwr.c
David Howells9ae326a2009-04-03 16:42:41 +0100203 */
204extern int cachefiles_read_or_alloc_page(struct fscache_retrieval *,
205 struct page *, gfp_t);
206extern int cachefiles_read_or_alloc_pages(struct fscache_retrieval *,
207 struct list_head *, unsigned *,
208 gfp_t);
209extern int cachefiles_allocate_page(struct fscache_retrieval *, struct page *,
210 gfp_t);
211extern int cachefiles_allocate_pages(struct fscache_retrieval *,
212 struct list_head *, unsigned *, gfp_t);
213extern int cachefiles_write_page(struct fscache_storage *, struct page *);
214extern void cachefiles_uncache_page(struct fscache_object *, struct page *);
215
216/*
David Howells911e6902009-05-27 15:46:55 +0100217 * security.c
David Howells9ae326a2009-04-03 16:42:41 +0100218 */
219extern int cachefiles_get_security_ID(struct cachefiles_cache *cache);
220extern int cachefiles_determine_cache_security(struct cachefiles_cache *cache,
221 struct dentry *root,
222 const struct cred **_saved_cred);
223
224static inline void cachefiles_begin_secure(struct cachefiles_cache *cache,
225 const struct cred **_saved_cred)
226{
227 *_saved_cred = override_creds(cache->cache_cred);
228}
229
230static inline void cachefiles_end_secure(struct cachefiles_cache *cache,
231 const struct cred *saved_cred)
232{
233 revert_creds(saved_cred);
234}
235
236/*
David Howells911e6902009-05-27 15:46:55 +0100237 * xattr.c
David Howells9ae326a2009-04-03 16:42:41 +0100238 */
239extern int cachefiles_check_object_type(struct cachefiles_object *object);
240extern int cachefiles_set_object_xattr(struct cachefiles_object *object,
241 struct cachefiles_xattr *auxdata);
242extern int cachefiles_update_object_xattr(struct cachefiles_object *object,
243 struct cachefiles_xattr *auxdata);
David Howells5002d7b2013-08-21 17:29:21 -0400244extern int cachefiles_check_auxdata(struct cachefiles_object *object);
David Howells9ae326a2009-04-03 16:42:41 +0100245extern int cachefiles_check_object_xattr(struct cachefiles_object *object,
246 struct cachefiles_xattr *auxdata);
247extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
248 struct dentry *dentry);
249
250
251/*
252 * error handling
253 */
David Howells9ae326a2009-04-03 16:42:41 +0100254
255#define cachefiles_io_error(___cache, FMT, ...) \
256do { \
Fabian Frederick6ff66ac2014-09-25 16:05:27 -0700257 pr_err("I/O Error: " FMT"\n", ##__VA_ARGS__); \
David Howells9ae326a2009-04-03 16:42:41 +0100258 fscache_io_error(&(___cache)->cache); \
259 set_bit(CACHEFILES_DEAD, &(___cache)->flags); \
260} while (0)
261
262#define cachefiles_io_error_obj(object, FMT, ...) \
263do { \
264 struct cachefiles_cache *___cache; \
265 \
266 ___cache = container_of((object)->fscache.cache, \
267 struct cachefiles_cache, cache); \
268 cachefiles_io_error(___cache, FMT, ##__VA_ARGS__); \
269} while (0)
270
271
272/*
273 * debug tracing
274 */
275#define dbgprintk(FMT, ...) \
276 printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
277
David Howells9ae326a2009-04-03 16:42:41 +0100278#define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
279#define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
280#define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
281
282
283#if defined(__KDEBUG)
284#define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
285#define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
286#define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
287
288#elif defined(CONFIG_CACHEFILES_DEBUG)
289#define _enter(FMT, ...) \
290do { \
291 if (cachefiles_debug & CACHEFILES_DEBUG_KENTER) \
292 kenter(FMT, ##__VA_ARGS__); \
293} while (0)
294
295#define _leave(FMT, ...) \
296do { \
297 if (cachefiles_debug & CACHEFILES_DEBUG_KLEAVE) \
298 kleave(FMT, ##__VA_ARGS__); \
299} while (0)
300
301#define _debug(FMT, ...) \
302do { \
303 if (cachefiles_debug & CACHEFILES_DEBUG_KDEBUG) \
304 kdebug(FMT, ##__VA_ARGS__); \
305} while (0)
306
307#else
David Howells12fdff32010-08-12 16:54:57 +0100308#define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
309#define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
310#define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
David Howells9ae326a2009-04-03 16:42:41 +0100311#endif
312
313#if 1 /* defined(__KDEBUGALL) */
314
315#define ASSERT(X) \
316do { \
317 if (unlikely(!(X))) { \
Fabian Frederick4e1eb882014-06-06 14:37:32 -0700318 pr_err("\n"); \
Fabian Frederick0227d6ab2014-06-06 14:37:33 -0700319 pr_err("Assertion failed\n"); \
David Howells9ae326a2009-04-03 16:42:41 +0100320 BUG(); \
321 } \
322} while (0)
323
324#define ASSERTCMP(X, OP, Y) \
325do { \
326 if (unlikely(!((X) OP (Y)))) { \
Fabian Frederick4e1eb882014-06-06 14:37:32 -0700327 pr_err("\n"); \
Fabian Frederick0227d6ab2014-06-06 14:37:33 -0700328 pr_err("Assertion failed\n"); \
Fabian Frederick4e1eb882014-06-06 14:37:32 -0700329 pr_err("%lx " #OP " %lx is false\n", \
David Howells9ae326a2009-04-03 16:42:41 +0100330 (unsigned long)(X), (unsigned long)(Y)); \
331 BUG(); \
332 } \
333} while (0)
334
335#define ASSERTIF(C, X) \
336do { \
337 if (unlikely((C) && !(X))) { \
Fabian Frederick4e1eb882014-06-06 14:37:32 -0700338 pr_err("\n"); \
Fabian Frederick0227d6ab2014-06-06 14:37:33 -0700339 pr_err("Assertion failed\n"); \
David Howells9ae326a2009-04-03 16:42:41 +0100340 BUG(); \
341 } \
342} while (0)
343
344#define ASSERTIFCMP(C, X, OP, Y) \
345do { \
346 if (unlikely((C) && !((X) OP (Y)))) { \
Fabian Frederick4e1eb882014-06-06 14:37:32 -0700347 pr_err("\n"); \
Fabian Frederick0227d6ab2014-06-06 14:37:33 -0700348 pr_err("Assertion failed\n"); \
Fabian Frederick4e1eb882014-06-06 14:37:32 -0700349 pr_err("%lx " #OP " %lx is false\n", \
David Howells9ae326a2009-04-03 16:42:41 +0100350 (unsigned long)(X), (unsigned long)(Y)); \
351 BUG(); \
352 } \
353} while (0)
354
355#else
356
357#define ASSERT(X) do {} while (0)
358#define ASSERTCMP(X, OP, Y) do {} while (0)
359#define ASSERTIF(C, X) do {} while (0)
360#define ASSERTIFCMP(C, X, OP, Y) do {} while (0)
361
362#endif