usr/src/sys/nfs/nfsrvcache.h

/*
 * Copyright (c) 1989 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)nfsrvcache.h        7.3 (Berkeley) %G%
 */

/*
 * Definitions for the server recent request cache
 */

#define NFSRVCACHESIZ   128
#define NFSRCHSZ        32

struct nfsrvcache {
        struct  nfsrvcache *rc_chain[2];        /* Hash chain links */
        struct  nfsrvcache *rc_next;    /* Lru list */
        struct  nfsrvcache *rc_prev;
        int     rc_state;               /* Current state of request */
        int     rc_flag;                /* Flag bits */
        struct  mbuf rc_nam;            /* Sockaddr of requestor */
        u_long  rc_xid;                 /* rpc id number */
        int     rc_proc;                /* rpc proc number */
        long    rc_timestamp;           /* Time stamp */
        union {
                struct mbuf *rc_repmb;  /* Reply mbuf list OR */
                int rc_repstat;         /* Reply status */
        } rc_un;
};

#define rc_forw         rc_chain[0]
#define rc_back         rc_chain[1]
#define rc_status       rc_un.rc_repstat
#define rc_reply        rc_un.rc_repmb

#define put_at_head(rp) \
                (rp)->rc_prev->rc_next = (rp)->rc_next; \
                (rp)->rc_next->rc_prev = (rp)->rc_prev; \
                (rp)->rc_next = nfsrvcachehead.rc_next; \
                (rp)->rc_next->rc_prev = (rp); \
                nfsrvcachehead.rc_next = (rp); \
                (rp)->rc_prev = &nfsrvcachehead

/* Cache entry states */
#define RC_UNUSED       0
#define RC_INPROG       1
#define RC_DONE         2

/* Return values */
#define RC_DROPIT       0
#define RC_REPLY        1
#define RC_DOIT         2

/* Flag bits */
#define RC_LOCKED       0x1
#define RC_WANTED       0x2
#define RC_REPSTATUS    0x4
#define RC_REPMBUF      0x8

/* Delay time after completion that request is dropped */
#define RC_DELAY        2               /* seconds */