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13#ifndef _LINUX_SUNRPC_CACHE_H_
14#define _LINUX_SUNRPC_CACHE_H_
15
16#include <linux/kref.h>
17#include <linux/slab.h>
18#include <linux/atomic.h>
19#include <linux/proc_fs.h>
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48struct cache_head {
49 struct hlist_node cache_list;
50 time_t expiry_time;
51 time_t last_refresh;
52
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54
55
56 struct kref ref;
57 unsigned long flags;
58};
59#define CACHE_VALID 0
60#define CACHE_NEGATIVE 1
61#define CACHE_PENDING 2
62#define CACHE_CLEANED 3
63
64#define CACHE_NEW_EXPIRY 120
65
66struct cache_detail {
67 struct module * owner;
68 int hash_size;
69 struct hlist_head * hash_table;
70 spinlock_t hash_lock;
71
72 char *name;
73 void (*cache_put)(struct kref *);
74
75 int (*cache_upcall)(struct cache_detail *,
76 struct cache_head *);
77
78 void (*cache_request)(struct cache_detail *cd,
79 struct cache_head *ch,
80 char **bpp, int *blen);
81
82 int (*cache_parse)(struct cache_detail *,
83 char *buf, int len);
84
85 int (*cache_show)(struct seq_file *m,
86 struct cache_detail *cd,
87 struct cache_head *h);
88 void (*warn_no_listener)(struct cache_detail *cd,
89 int has_died);
90
91 struct cache_head * (*alloc)(void);
92 int (*match)(struct cache_head *orig, struct cache_head *new);
93 void (*init)(struct cache_head *orig, struct cache_head *new);
94 void (*update)(struct cache_head *orig, struct cache_head *new);
95
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99 time_t flush_time;
100
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103
104
105 struct list_head others;
106 time_t nextcheck;
107 int entries;
108
109
110 struct list_head queue;
111
112 atomic_t readers;
113 time_t last_close;
114 time_t last_warn;
115
116 union {
117 struct proc_dir_entry *procfs;
118 struct dentry *pipefs;
119 };
120 struct net *net;
121};
122
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126
127
128struct cache_req {
129 struct cache_deferred_req *(*defer)(struct cache_req *req);
130 int thread_wait;
131
132
133};
134
135
136
137struct cache_deferred_req {
138 struct hlist_node hash;
139 struct list_head recent;
140 struct cache_head *item;
141 void *owner;
142
143 void (*revisit)(struct cache_deferred_req *req,
144 int too_many);
145};
146
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151
152static inline time_t seconds_since_boot(void)
153{
154 struct timespec boot;
155 getboottime(&boot);
156 return get_seconds() - boot.tv_sec;
157}
158
159static inline time_t convert_to_wallclock(time_t sinceboot)
160{
161 struct timespec boot;
162 getboottime(&boot);
163 return boot.tv_sec + sinceboot;
164}
165
166extern const struct file_operations cache_file_operations_pipefs;
167extern const struct file_operations content_file_operations_pipefs;
168extern const struct file_operations cache_flush_operations_pipefs;
169
170extern struct cache_head *
171sunrpc_cache_lookup_rcu(struct cache_detail *detail,
172 struct cache_head *key, int hash);
173extern struct cache_head *
174sunrpc_cache_update(struct cache_detail *detail,
175 struct cache_head *new, struct cache_head *old, int hash);
176
177extern int
178sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h);
179
180
181extern void cache_clean_deferred(void *owner);
182
183static inline struct cache_head *cache_get(struct cache_head *h)
184{
185 kref_get(&h->ref);
186 return h;
187}
188
189static inline struct cache_head *cache_get_rcu(struct cache_head *h)
190{
191 if (kref_get_unless_zero(&h->ref))
192 return h;
193 return NULL;
194}
195
196static inline void cache_put(struct cache_head *h, struct cache_detail *cd)
197{
198 if (kref_read(&h->ref) <= 2 &&
199 h->expiry_time < cd->nextcheck)
200 cd->nextcheck = h->expiry_time;
201 kref_put(&h->ref, cd->cache_put);
202}
203
204static inline bool cache_is_expired(struct cache_detail *detail, struct cache_head *h)
205{
206 if (!test_bit(CACHE_VALID, &h->flags))
207 return false;
208
209 return (h->expiry_time < seconds_since_boot()) ||
210 (detail->flush_time >= h->last_refresh);
211}
212
213extern int cache_check(struct cache_detail *detail,
214 struct cache_head *h, struct cache_req *rqstp);
215extern void cache_flush(void);
216extern void cache_purge(struct cache_detail *detail);
217#define NEVER (0x7FFFFFFF)
218extern void __init cache_initialize(void);
219extern int cache_register_net(struct cache_detail *cd, struct net *net);
220extern void cache_unregister_net(struct cache_detail *cd, struct net *net);
221
222extern struct cache_detail *cache_create_net(const struct cache_detail *tmpl, struct net *net);
223extern void cache_destroy_net(struct cache_detail *cd, struct net *net);
224
225extern void sunrpc_init_cache_detail(struct cache_detail *cd);
226extern void sunrpc_destroy_cache_detail(struct cache_detail *cd);
227extern int sunrpc_cache_register_pipefs(struct dentry *parent, const char *,
228 umode_t, struct cache_detail *);
229extern void sunrpc_cache_unregister_pipefs(struct cache_detail *);
230extern void sunrpc_cache_unhash(struct cache_detail *, struct cache_head *);
231
232
233extern void *cache_seq_start_rcu(struct seq_file *file, loff_t *pos);
234extern void *cache_seq_next_rcu(struct seq_file *file, void *p, loff_t *pos);
235extern void cache_seq_stop_rcu(struct seq_file *file, void *p);
236
237extern void qword_add(char **bpp, int *lp, char *str);
238extern void qword_addhex(char **bpp, int *lp, char *buf, int blen);
239extern int qword_get(char **bpp, char *dest, int bufsize);
240
241static inline int get_int(char **bpp, int *anint)
242{
243 char buf[50];
244 char *ep;
245 int rv;
246 int len = qword_get(bpp, buf, sizeof(buf));
247
248 if (len < 0)
249 return -EINVAL;
250 if (len == 0)
251 return -ENOENT;
252
253 rv = simple_strtol(buf, &ep, 0);
254 if (*ep)
255 return -EINVAL;
256
257 *anint = rv;
258 return 0;
259}
260
261static inline int get_uint(char **bpp, unsigned int *anint)
262{
263 char buf[50];
264 int len = qword_get(bpp, buf, sizeof(buf));
265
266 if (len < 0)
267 return -EINVAL;
268 if (len == 0)
269 return -ENOENT;
270
271 if (kstrtouint(buf, 0, anint))
272 return -EINVAL;
273
274 return 0;
275}
276
277static inline int get_time(char **bpp, time_t *time)
278{
279 char buf[50];
280 long long ll;
281 int len = qword_get(bpp, buf, sizeof(buf));
282
283 if (len < 0)
284 return -EINVAL;
285 if (len == 0)
286 return -ENOENT;
287
288 if (kstrtoll(buf, 0, &ll))
289 return -EINVAL;
290
291 *time = (time_t)ll;
292 return 0;
293}
294
295static inline time_t get_expiry(char **bpp)
296{
297 time_t rv;
298 struct timespec boot;
299
300 if (get_time(bpp, &rv))
301 return 0;
302 if (rv < 0)
303 return 0;
304 getboottime(&boot);
305 return rv - boot.tv_sec;
306}
307
308#endif
309