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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07002 * Request reply cache. This was heavily inspired by the
3 * implementation in 4.3BSD/4.4BSD.
4 *
5 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
6 */
7
8#ifndef NFSCACHE_H
9#define NFSCACHE_H
10
Boaz Harrosh72579ac2009-12-03 20:28:59 +020011#include <linux/sunrpc/svc.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012
13/*
Greg Banksfca42172009-04-01 07:28:13 +110014 * Representation of a reply cache entry.
Linus Torvalds1da177e2005-04-16 15:20:36 -070015 */
16struct svc_cacherep {
17 struct hlist_node c_hash;
18 struct list_head c_lru;
19
20 unsigned char c_state, /* unused, inprog, done */
21 c_type, /* status, buffer */
22 c_secure : 1; /* req came from port < 1024 */
23 struct sockaddr_in c_addr;
Al Viroc7afef12006-10-19 23:29:02 -070024 __be32 c_xid;
Linus Torvalds1da177e2005-04-16 15:20:36 -070025 u32 c_prot;
26 u32 c_proc;
27 u32 c_vers;
28 unsigned long c_timestamp;
29 union {
30 struct kvec u_vec;
Al Viroc7afef12006-10-19 23:29:02 -070031 __be32 u_status;
Linus Torvalds1da177e2005-04-16 15:20:36 -070032 } c_u;
33};
34
35#define c_replvec c_u.u_vec
36#define c_replstat c_u.u_status
37
38/* cache entry states */
39enum {
40 RC_UNUSED,
41 RC_INPROG,
42 RC_DONE
43};
44
45/* return values */
46enum {
47 RC_DROPIT,
48 RC_REPLY,
49 RC_DOIT,
50 RC_INTR
51};
52
53/*
54 * Cache types.
55 * We may want to add more types one day, e.g. for diropres and
56 * attrstat replies. Using cache entries with fixed length instead
57 * of buffer pointers may be more efficient.
58 */
59enum {
60 RC_NOCACHE,
61 RC_REPLSTAT,
62 RC_REPLBUFF,
63};
64
65/*
66 * If requests are retransmitted within this interval, they're dropped.
67 */
68#define RC_DELAY (HZ/5)
69
J. Bruce Fieldsd5c34282007-11-09 14:10:56 -050070int nfsd_reply_cache_init(void);
71void nfsd_reply_cache_shutdown(void);
J. Bruce Fields10910062011-01-24 12:11:02 -050072int nfsd_cache_lookup(struct svc_rqst *);
Al Viroc7afef12006-10-19 23:29:02 -070073void nfsd_cache_update(struct svc_rqst *, int, __be32 *);
Benny Halevy04826f42009-04-06 12:00:49 +030074
75#ifdef CONFIG_NFSD_V4
Andy Adamson074fe892009-04-03 08:28:15 +030076void nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp);
Benny Halevy04826f42009-04-06 12:00:49 +030077#else /* CONFIG_NFSD_V4 */
78static inline void nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp)
79{
80}
81#endif /* CONFIG_NFSD_V4 */
Linus Torvalds1da177e2005-04-16 15:20:36 -070082
Linus Torvalds1da177e2005-04-16 15:20:36 -070083#endif /* NFSCACHE_H */