/*      $NetBSD: nfsrvcache.h,v 1.2 2016/12/13 22:52:46 pgoyette Exp $  */
/*-
 * Copyright (c) 1989, 1993
 *      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.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * FreeBSD: head/sys/fs/nfs/nfsrvcache.h 269347 2014-07-31 19:24:44Z kib 
 * $NetBSD: nfsrvcache.h,v 1.2 2016/12/13 22:52:46 pgoyette Exp $
 */

#ifndef _NFS_NFSRVCACHE_H_
#define _NFS_NFSRVCACHE_H_

/*
 * Definitions for the server recent request cache
 */
#define NFSRVCACHE_MAX_SIZE     2048
#define NFSRVCACHE_MIN_SIZE       64

#define NFSRVCACHE_HASHSIZE     500

/* Cache table entry. */
struct nfsrvcache {
        LIST_ENTRY(nfsrvcache) rc_hash;         /* Hash chain */
        LIST_ENTRY(nfsrvcache) rc_ahash;        /* ACK hash chain */
        TAILQ_ENTRY(nfsrvcache) rc_lru;         /* UDP lru chain */
        u_int32_t       rc_xid;                 /* rpc id number */
        time_t          rc_timestamp;           /* Time done */
        union {
                mbuf_t repmb;                   /* Reply mbuf list OR */
                int repstat;                    /* Reply status */
        } rc_un;
        union {
                struct {
                        union nethostaddr haddr; /* Host address */
                } udp;
                struct {
                        u_int64_t       sockref;
                        u_int32_t       len;
                        u_int32_t       tcpseq;
                        int16_t         refcnt;
                        u_int16_t       cksum;
                        time_t          cachetime;
                        int             acked;
                } ot;
        } rc_un2;
        u_int16_t       rc_proc;                /* rpc proc number */
        u_int16_t       rc_flag;                /* Flag bits */
};

#define rc_reply        rc_un.repmb
#define rc_status       rc_un.repstat
#define rc_inet         rc_un2.udp.haddr.had_inet.s_addr
#define rc_inet6        rc_un2.udp.haddr.had_inet6
#define rc_haddr        rc_un2.udp.haddr
#define rc_sockref      rc_un2.ot.sockref
#define rc_tcpseq       rc_un2.ot.tcpseq
#define rc_refcnt       rc_un2.ot.refcnt
#define rc_reqlen       rc_un2.ot.len
#define rc_cksum        rc_un2.ot.cksum
#define rc_cachetime    rc_un2.ot.cachetime
#define rc_acked        rc_un2.ot.acked

/* TCP ACK values */
#define RC_NO_SEQ               0
#define RC_NO_ACK               1
#define RC_ACK                  2
#define RC_NACK                 3

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

/* Flag bits */
#define RC_LOCKED       0x0001
#define RC_WANTED       0x0002
#define RC_REPSTATUS    0x0004
#define RC_REPMBUF      0x0008
#define RC_UDP          0x0010
#define RC_INETIPV6     0x0020
#define RC_INPROG       0x0040
#define RC_NFSV2        0x0100
#define RC_NFSV3        0x0200
#define RC_NFSV4        0x0400
#define RC_NFSVERS      (RC_NFSV2 | RC_NFSV3 | RC_NFSV4)
#define RC_REFCNT       0x0800
#define RC_SAMETCPCONN  0x1000

LIST_HEAD(nfsrvhashhead, nfsrvcache);

/* The fine-grained locked cache hash table for TCP. */
struct nfsrchash_bucket {
        struct kmutex           mtx;
        struct nfsrvhashhead    tbl;
};

#endif  /* _NFS_NFSRVCACHE_H_ */