[deliverable/linux.git] / fs / nfsd / cache.h

/*
 * 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.
 */
struct svc_cacherep {
	struct hlist_node	c_hash;
	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_in	c_addr;
	__be32			c_xid;
	u32			c_prot;
	u32			c_proc;
	u32			c_vers;
	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,
	RC_INTR
};

/*
 * 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)

int	nfsd_reply_cache_init(void);
void	nfsd_reply_cache_shutdown(void);
int	nfsd_cache_lookup(struct svc_rqst *, int);
void	nfsd_cache_update(struct svc_rqst *, int, __be32 *);

#ifdef CONFIG_NFSD_V4
void	nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp);
#else  /* CONFIG_NFSD_V4 */
static inline void nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp)
{
}
#endif /* CONFIG_NFSD_V4 */

#endif /* NFSCACHE_H */
Commit	Line	Data
1da177e4	1	/*
1da177e4 LT	2	* 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
72579ac9	11	#include <linux/sunrpc/svc.h>
1da177e4 LT	12
1da177e4 LT	13	/*
fca4217c	14	* Representation of a reply cache entry.
1da177e4 LT	15	*/
	16	struct 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;
c7afef1f	24	__be32 c_xid;
1da177e4 LT	25	u32 c_prot;
	26	u32 c_proc;
	27	u32 c_vers;
	28	unsigned long c_timestamp;
	29	union {
	30	struct kvec u_vec;
c7afef1f	31	__be32 u_status;
1da177e4 LT	32	} 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 */
	39	enum {
	40	RC_UNUSED,
	41	RC_INPROG,
	42	RC_DONE
	43	};
	44
	45	/* return values */
	46	enum {
	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	*/
	59	enum {
	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
d5c3428b BF	70	int nfsd_reply_cache_init(void);
d5c3428b BF	71	void nfsd_reply_cache_shutdown(void);
1da177e4	72	int nfsd_cache_lookup(struct svc_rqst *, int);
c7afef1f	73	void nfsd_cache_update(struct svc_rqst , int, __be32 );
04826f43 BH	74
04826f43 BH	75	#ifdef CONFIG_NFSD_V4
074fe897	76	void nfsd4_set_statp(struct svc_rqst rqstp, __be32 statp);
04826f43 BH	77	#else /* CONFIG_NFSD_V4 */
	78	static inline void nfsd4_set_statp(struct svc_rqst rqstp, __be32 statp)
	79	{
	80	}
	81	#endif /* CONFIG_NFSD_V4 */
1da177e4	82
1da177e4	83	#endif /* NFSCACHE_H */