88 lines
1.8 KiB
C
88 lines
1.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Request reply cache. This was heavily inspired by the
|
|
* implementation in 4.3BSD/4.4BSD.
|
|
*
|
|
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
|
|
*/
|
|
|
|
#ifndef NFSCACHE_H
|
|
#define NFSCACHE_H
|
|
|
|
#include <linux/sunrpc/svc.h>
|
|
|
|
/*
|
|
* Representation of a reply cache entry.
|
|
*
|
|
* Note that we use a sockaddr_in6 to hold the address instead of the more
|
|
* typical sockaddr_storage. This is for space reasons, since sockaddr_storage
|
|
* is much larger than a sockaddr_in6.
|
|
*/
|
|
struct svc_cacherep {
|
|
struct list_head c_lru;
|
|
|
|
unsigned char c_state, /* unused, inprog, done */
|
|
c_type, /* status, buffer */
|
|
c_secure : 1; /* req came from port < 1024 */
|
|
struct sockaddr_in6 c_addr;
|
|
__be32 c_xid;
|
|
u32 c_prot;
|
|
u32 c_proc;
|
|
u32 c_vers;
|
|
unsigned int c_len;
|
|
__wsum c_csum;
|
|
unsigned long c_timestamp;
|
|
union {
|
|
struct kvec u_vec;
|
|
__be32 u_status;
|
|
} c_u;
|
|
};
|
|
|
|
#define c_replvec c_u.u_vec
|
|
#define c_replstat c_u.u_status
|
|
|
|
/* cache entry states */
|
|
enum {
|
|
RC_UNUSED,
|
|
RC_INPROG,
|
|
RC_DONE
|
|
};
|
|
|
|
/* return values */
|
|
enum {
|
|
RC_DROPIT,
|
|
RC_REPLY,
|
|
RC_DOIT
|
|
};
|
|
|
|
/*
|
|
* Cache types.
|
|
* We may want to add more types one day, e.g. for diropres and
|
|
* attrstat replies. Using cache entries with fixed length instead
|
|
* of buffer pointers may be more efficient.
|
|
*/
|
|
enum {
|
|
RC_NOCACHE,
|
|
RC_REPLSTAT,
|
|
RC_REPLBUFF,
|
|
};
|
|
|
|
/*
|
|
* If requests are retransmitted within this interval, they're dropped.
|
|
*/
|
|
#define RC_DELAY (HZ/5)
|
|
|
|
/* Cache entries expire after this time period */
|
|
#define RC_EXPIRE (120 * HZ)
|
|
|
|
/* Checksum this amount of the request */
|
|
#define RC_CSUMLEN (256U)
|
|
|
|
int nfsd_reply_cache_init(void);
|
|
void nfsd_reply_cache_shutdown(void);
|
|
int nfsd_cache_lookup(struct svc_rqst *);
|
|
void nfsd_cache_update(struct svc_rqst *, int, __be32 *);
|
|
int nfsd_reply_cache_stats_open(struct inode *, struct file *);
|
|
|
|
#endif /* NFSCACHE_H */
|