Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/hid/hid
[linux-2.6-microblaze.git] / fs / cachefiles / internal.h
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /* General netfs cache on cache files internal defs
3  *
4  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
5  * Written by David Howells (dhowells@redhat.com)
6  */
7
8 #ifdef pr_fmt
9 #undef pr_fmt
10 #endif
11
12 #define pr_fmt(fmt) "CacheFiles: " fmt
13
14
15 #include <linux/fscache-cache.h>
16 #include <linux/timer.h>
17 #include <linux/wait_bit.h>
18 #include <linux/cred.h>
19 #include <linux/workqueue.h>
20 #include <linux/security.h>
21
22 struct cachefiles_cache;
23 struct cachefiles_object;
24
25 extern unsigned cachefiles_debug;
26 #define CACHEFILES_DEBUG_KENTER 1
27 #define CACHEFILES_DEBUG_KLEAVE 2
28 #define CACHEFILES_DEBUG_KDEBUG 4
29
30 #define cachefiles_gfp (__GFP_RECLAIM | __GFP_NORETRY | __GFP_NOMEMALLOC)
31
32 /*
33  * node records
34  */
35 struct cachefiles_object {
36         struct fscache_object           fscache;        /* fscache handle */
37         struct cachefiles_lookup_data   *lookup_data;   /* cached lookup data */
38         struct dentry                   *dentry;        /* the file/dir representing this object */
39         struct dentry                   *backer;        /* backing file */
40         loff_t                          i_size;         /* object size */
41         unsigned long                   flags;
42 #define CACHEFILES_OBJECT_ACTIVE        0               /* T if marked active */
43         atomic_t                        usage;          /* object usage count */
44         uint8_t                         type;           /* object type */
45         uint8_t                         new;            /* T if object new */
46         spinlock_t                      work_lock;
47         struct rb_node                  active_node;    /* link in active tree (dentry is key) */
48 };
49
50 extern struct kmem_cache *cachefiles_object_jar;
51
52 /*
53  * Cache files cache definition
54  */
55 struct cachefiles_cache {
56         struct fscache_cache            cache;          /* FS-Cache record */
57         struct vfsmount                 *mnt;           /* mountpoint holding the cache */
58         struct dentry                   *graveyard;     /* directory into which dead objects go */
59         struct file                     *cachefilesd;   /* manager daemon handle */
60         const struct cred               *cache_cred;    /* security override for accessing cache */
61         struct mutex                    daemon_mutex;   /* command serialisation mutex */
62         wait_queue_head_t               daemon_pollwq;  /* poll waitqueue for daemon */
63         struct rb_root                  active_nodes;   /* active nodes (can't be culled) */
64         rwlock_t                        active_lock;    /* lock for active_nodes */
65         atomic_t                        gravecounter;   /* graveyard uniquifier */
66         atomic_t                        f_released;     /* number of objects released lately */
67         atomic_long_t                   b_released;     /* number of blocks released lately */
68         unsigned                        frun_percent;   /* when to stop culling (% files) */
69         unsigned                        fcull_percent;  /* when to start culling (% files) */
70         unsigned                        fstop_percent;  /* when to stop allocating (% files) */
71         unsigned                        brun_percent;   /* when to stop culling (% blocks) */
72         unsigned                        bcull_percent;  /* when to start culling (% blocks) */
73         unsigned                        bstop_percent;  /* when to stop allocating (% blocks) */
74         unsigned                        bsize;          /* cache's block size */
75         unsigned                        bshift;         /* min(ilog2(PAGE_SIZE / bsize), 0) */
76         uint64_t                        frun;           /* when to stop culling */
77         uint64_t                        fcull;          /* when to start culling */
78         uint64_t                        fstop;          /* when to stop allocating */
79         sector_t                        brun;           /* when to stop culling */
80         sector_t                        bcull;          /* when to start culling */
81         sector_t                        bstop;          /* when to stop allocating */
82         unsigned long                   flags;
83 #define CACHEFILES_READY                0       /* T if cache prepared */
84 #define CACHEFILES_DEAD                 1       /* T if cache dead */
85 #define CACHEFILES_CULLING              2       /* T if cull engaged */
86 #define CACHEFILES_STATE_CHANGED        3       /* T if state changed (poll trigger) */
87         char                            *rootdirname;   /* name of cache root directory */
88         char                            *secctx;        /* LSM security context */
89         char                            *tag;           /* cache binding tag */
90 };
91
92 /*
93  * backing file read tracking
94  */
95 struct cachefiles_one_read {
96         wait_queue_entry_t                      monitor;        /* link into monitored waitqueue */
97         struct page                     *back_page;     /* backing file page we're waiting for */
98         struct page                     *netfs_page;    /* netfs page we're going to fill */
99         struct fscache_retrieval        *op;            /* retrieval op covering this */
100         struct list_head                op_link;        /* link in op's todo list */
101 };
102
103 /*
104  * backing file write tracking
105  */
106 struct cachefiles_one_write {
107         struct page                     *netfs_page;    /* netfs page to copy */
108         struct cachefiles_object        *object;
109         struct list_head                obj_link;       /* link in object's lists */
110         fscache_rw_complete_t           end_io_func;
111         void                            *context;
112 };
113
114 /*
115  * auxiliary data xattr buffer
116  */
117 struct cachefiles_xattr {
118         uint16_t                        len;
119         uint8_t                         type;
120         uint8_t                         data[];
121 };
122
123 #include <trace/events/cachefiles.h>
124
125 /*
126  * note change of state for daemon
127  */
128 static inline void cachefiles_state_changed(struct cachefiles_cache *cache)
129 {
130         set_bit(CACHEFILES_STATE_CHANGED, &cache->flags);
131         wake_up_all(&cache->daemon_pollwq);
132 }
133
134 /*
135  * bind.c
136  */
137 extern int cachefiles_daemon_bind(struct cachefiles_cache *cache, char *args);
138 extern void cachefiles_daemon_unbind(struct cachefiles_cache *cache);
139
140 /*
141  * daemon.c
142  */
143 extern const struct file_operations cachefiles_daemon_fops;
144
145 extern int cachefiles_has_space(struct cachefiles_cache *cache,
146                                 unsigned fnr, unsigned bnr);
147
148 /*
149  * interface.c
150  */
151 extern const struct fscache_cache_ops cachefiles_cache_ops;
152
153 /*
154  * key.c
155  */
156 extern char *cachefiles_cook_key(const u8 *raw, int keylen, uint8_t type);
157
158 /*
159  * namei.c
160  */
161 extern void cachefiles_mark_object_inactive(struct cachefiles_cache *cache,
162                                             struct cachefiles_object *object,
163                                             blkcnt_t i_blocks);
164 extern int cachefiles_delete_object(struct cachefiles_cache *cache,
165                                     struct cachefiles_object *object);
166 extern int cachefiles_walk_to_object(struct cachefiles_object *parent,
167                                      struct cachefiles_object *object,
168                                      const char *key,
169                                      struct cachefiles_xattr *auxdata);
170 extern struct dentry *cachefiles_get_directory(struct cachefiles_cache *cache,
171                                                struct dentry *dir,
172                                                const char *name);
173
174 extern int cachefiles_cull(struct cachefiles_cache *cache, struct dentry *dir,
175                            char *filename);
176
177 extern int cachefiles_check_in_use(struct cachefiles_cache *cache,
178                                    struct dentry *dir, char *filename);
179
180 /*
181  * proc.c
182  */
183 #ifdef CONFIG_CACHEFILES_HISTOGRAM
184 extern atomic_t cachefiles_lookup_histogram[HZ];
185 extern atomic_t cachefiles_mkdir_histogram[HZ];
186 extern atomic_t cachefiles_create_histogram[HZ];
187
188 extern int __init cachefiles_proc_init(void);
189 extern void cachefiles_proc_cleanup(void);
190 static inline
191 void cachefiles_hist(atomic_t histogram[], unsigned long start_jif)
192 {
193         unsigned long jif = jiffies - start_jif;
194         if (jif >= HZ)
195                 jif = HZ - 1;
196         atomic_inc(&histogram[jif]);
197 }
198
199 #else
200 #define cachefiles_proc_init()          (0)
201 #define cachefiles_proc_cleanup()       do {} while (0)
202 #define cachefiles_hist(hist, start_jif) do {} while (0)
203 #endif
204
205 /*
206  * rdwr.c
207  */
208 extern int cachefiles_read_or_alloc_page(struct fscache_retrieval *,
209                                          struct page *, gfp_t);
210 extern int cachefiles_read_or_alloc_pages(struct fscache_retrieval *,
211                                           struct list_head *, unsigned *,
212                                           gfp_t);
213 extern int cachefiles_allocate_page(struct fscache_retrieval *, struct page *,
214                                     gfp_t);
215 extern int cachefiles_allocate_pages(struct fscache_retrieval *,
216                                      struct list_head *, unsigned *, gfp_t);
217 extern int cachefiles_write_page(struct fscache_storage *, struct page *);
218 extern void cachefiles_uncache_page(struct fscache_object *, struct page *);
219
220 /*
221  * security.c
222  */
223 extern int cachefiles_get_security_ID(struct cachefiles_cache *cache);
224 extern int cachefiles_determine_cache_security(struct cachefiles_cache *cache,
225                                                struct dentry *root,
226                                                const struct cred **_saved_cred);
227
228 static inline void cachefiles_begin_secure(struct cachefiles_cache *cache,
229                                            const struct cred **_saved_cred)
230 {
231         *_saved_cred = override_creds(cache->cache_cred);
232 }
233
234 static inline void cachefiles_end_secure(struct cachefiles_cache *cache,
235                                          const struct cred *saved_cred)
236 {
237         revert_creds(saved_cred);
238 }
239
240 /*
241  * xattr.c
242  */
243 extern int cachefiles_check_object_type(struct cachefiles_object *object);
244 extern int cachefiles_set_object_xattr(struct cachefiles_object *object,
245                                        struct cachefiles_xattr *auxdata);
246 extern int cachefiles_update_object_xattr(struct cachefiles_object *object,
247                                           struct cachefiles_xattr *auxdata);
248 extern int cachefiles_check_auxdata(struct cachefiles_object *object);
249 extern int cachefiles_check_object_xattr(struct cachefiles_object *object,
250                                          struct cachefiles_xattr *auxdata);
251 extern int cachefiles_remove_object_xattr(struct cachefiles_cache *cache,
252                                           struct dentry *dentry);
253
254
255 /*
256  * error handling
257  */
258
259 #define cachefiles_io_error(___cache, FMT, ...)         \
260 do {                                                    \
261         pr_err("I/O Error: " FMT"\n", ##__VA_ARGS__);   \
262         fscache_io_error(&(___cache)->cache);           \
263         set_bit(CACHEFILES_DEAD, &(___cache)->flags);   \
264 } while (0)
265
266 #define cachefiles_io_error_obj(object, FMT, ...)                       \
267 do {                                                                    \
268         struct cachefiles_cache *___cache;                              \
269                                                                         \
270         ___cache = container_of((object)->fscache.cache,                \
271                                 struct cachefiles_cache, cache);        \
272         cachefiles_io_error(___cache, FMT, ##__VA_ARGS__);              \
273 } while (0)
274
275
276 /*
277  * debug tracing
278  */
279 #define dbgprintk(FMT, ...) \
280         printk(KERN_DEBUG "[%-6.6s] "FMT"\n", current->comm, ##__VA_ARGS__)
281
282 #define kenter(FMT, ...) dbgprintk("==> %s("FMT")", __func__, ##__VA_ARGS__)
283 #define kleave(FMT, ...) dbgprintk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
284 #define kdebug(FMT, ...) dbgprintk(FMT, ##__VA_ARGS__)
285
286
287 #if defined(__KDEBUG)
288 #define _enter(FMT, ...) kenter(FMT, ##__VA_ARGS__)
289 #define _leave(FMT, ...) kleave(FMT, ##__VA_ARGS__)
290 #define _debug(FMT, ...) kdebug(FMT, ##__VA_ARGS__)
291
292 #elif defined(CONFIG_CACHEFILES_DEBUG)
293 #define _enter(FMT, ...)                                \
294 do {                                                    \
295         if (cachefiles_debug & CACHEFILES_DEBUG_KENTER) \
296                 kenter(FMT, ##__VA_ARGS__);             \
297 } while (0)
298
299 #define _leave(FMT, ...)                                \
300 do {                                                    \
301         if (cachefiles_debug & CACHEFILES_DEBUG_KLEAVE) \
302                 kleave(FMT, ##__VA_ARGS__);             \
303 } while (0)
304
305 #define _debug(FMT, ...)                                \
306 do {                                                    \
307         if (cachefiles_debug & CACHEFILES_DEBUG_KDEBUG) \
308                 kdebug(FMT, ##__VA_ARGS__);             \
309 } while (0)
310
311 #else
312 #define _enter(FMT, ...) no_printk("==> %s("FMT")", __func__, ##__VA_ARGS__)
313 #define _leave(FMT, ...) no_printk("<== %s()"FMT"", __func__, ##__VA_ARGS__)
314 #define _debug(FMT, ...) no_printk(FMT, ##__VA_ARGS__)
315 #endif
316
317 #if 1 /* defined(__KDEBUGALL) */
318
319 #define ASSERT(X)                                                       \
320 do {                                                                    \
321         if (unlikely(!(X))) {                                           \
322                 pr_err("\n");                                           \
323                 pr_err("Assertion failed\n");           \
324                 BUG();                                                  \
325         }                                                               \
326 } while (0)
327
328 #define ASSERTCMP(X, OP, Y)                                             \
329 do {                                                                    \
330         if (unlikely(!((X) OP (Y)))) {                                  \
331                 pr_err("\n");                                           \
332                 pr_err("Assertion failed\n");           \
333                 pr_err("%lx " #OP " %lx is false\n",                    \
334                        (unsigned long)(X), (unsigned long)(Y));         \
335                 BUG();                                                  \
336         }                                                               \
337 } while (0)
338
339 #define ASSERTIF(C, X)                                                  \
340 do {                                                                    \
341         if (unlikely((C) && !(X))) {                                    \
342                 pr_err("\n");                                           \
343                 pr_err("Assertion failed\n");           \
344                 BUG();                                                  \
345         }                                                               \
346 } while (0)
347
348 #define ASSERTIFCMP(C, X, OP, Y)                                        \
349 do {                                                                    \
350         if (unlikely((C) && !((X) OP (Y)))) {                           \
351                 pr_err("\n");                                           \
352                 pr_err("Assertion failed\n");           \
353                 pr_err("%lx " #OP " %lx is false\n",                    \
354                        (unsigned long)(X), (unsigned long)(Y));         \
355                 BUG();                                                  \
356         }                                                               \
357 } while (0)
358
359 #else
360
361 #define ASSERT(X)                       do {} while (0)
362 #define ASSERTCMP(X, OP, Y)             do {} while (0)
363 #define ASSERTIF(C, X)                  do {} while (0)
364 #define ASSERTIFCMP(C, X, OP, Y)        do {} while (0)
365
366 #endif