/* $OpenBSD: nfs_srvcache.c,v 1.2 1996/02/29 09:24:55 niklas Exp $ */ /* $NetBSD: nfs_srvcache.c,v 1.11 1996/02/09 21:48:32 christos 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 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. * * @(#)nfs_srvcache.c 8.2 (Berkeley) 8/18/94 */ /* * Reference: Chet Juszczak, "Improving the Performance and Correctness * of an NFS Server", in Proc. Winter 1989 USENIX Conference, * pages 53-63. San Diego, February 1989. */ #include #include #include #include #include #include #include #include #include #include #include #ifdef ISO #include #endif #include #include #include #include #include #include #include long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; #define NFSRCHASH(xid) \ (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; u_long nfsrvhash; #define TRUE 1 #define FALSE 0 #define NETFAMILY(rp) \ (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) /* * Static array that defines which nfs rpc's are nonidempotent */ int nonidempotent[NFS_NPROCS] = { FALSE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, }; /* True iff the rpc reply is an nfs status ONLY! */ static int repliesstatus[NFS_NPROCS] = { FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE, TRUE, TRUE, TRUE, FALSE, TRUE, FALSE, FALSE, FALSE, FALSE, FALSE, FALSE, TRUE, }; /* * Initialize the server request cache list */ void nfsrv_initcache() { nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash); TAILQ_INIT(&nfsrvlruhead); } /* * Look for the request in the cache * If found then * return action and optionally reply * else * insert it in the cache * * The rules are as follows: * - if in progress, return DROP request * - if completed within DELAY of the current time, return DROP it * - if completed a longer time ago return REPLY if the reply was cached or * return DOIT * Update/add new request at end of lru list */ int nfsrv_getcache(nam, nd, repp) struct mbuf *nam; register struct nfsd *nd; struct mbuf **repp; { register struct nfsrvcache *rp; struct mbuf *mb; struct sockaddr_in *saddr; caddr_t bpos; int ret; if (nd->nd_nqlflag != NQL_NOVAL) return (RC_DOIT); loop: for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; rp = rp->rc_hash.le_next) { if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nam)) { if ((rp->rc_flag & RC_LOCKED) != 0) { rp->rc_flag |= RC_WANTED; (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); goto loop; } rp->rc_flag |= RC_LOCKED; /* If not at end of LRU chain, move it there */ if (rp->rc_lru.tqe_next) { TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); } if (rp->rc_state == RC_UNUSED) panic("nfsrv cache"); if (rp->rc_state == RC_INPROG) { nfsstats.srvcache_inproghits++; ret = RC_DROPIT; } else if (rp->rc_flag & RC_REPSTATUS) { nfsstats.srvcache_nonidemdonehits++; nfs_rephead(0, nd, rp->rc_status, 0, (u_quad_t *)0, repp, &mb, &bpos); ret = RC_REPLY; } else if (rp->rc_flag & RC_REPMBUF) { nfsstats.srvcache_nonidemdonehits++; *repp = m_copym(rp->rc_reply, 0, M_COPYALL, M_WAIT); ret = RC_REPLY; } else { nfsstats.srvcache_idemdonehits++; rp->rc_state = RC_INPROG; ret = RC_DOIT; } rp->rc_flag &= ~RC_LOCKED; if (rp->rc_flag & RC_WANTED) { rp->rc_flag &= ~RC_WANTED; wakeup((caddr_t)rp); } return (ret); } } nfsstats.srvcache_misses++; if (numnfsrvcache < desirednfsrvcache) { rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, M_NFSD, M_WAITOK); bzero((char *)rp, sizeof *rp); numnfsrvcache++; rp->rc_flag = RC_LOCKED; } else { rp = nfsrvlruhead.tqh_first; while ((rp->rc_flag & RC_LOCKED) != 0) { rp->rc_flag |= RC_WANTED; (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); rp = nfsrvlruhead.tqh_first; } rp->rc_flag |= RC_LOCKED; LIST_REMOVE(rp, rc_hash); TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); if (rp->rc_flag & RC_REPMBUF) m_freem(rp->rc_reply); if (rp->rc_flag & RC_NAM) MFREE(rp->rc_nam, mb); rp->rc_flag &= (RC_LOCKED | RC_WANTED); } TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); rp->rc_state = RC_INPROG; rp->rc_xid = nd->nd_retxid; saddr = mtod(nam, struct sockaddr_in *); switch (saddr->sin_family) { case AF_INET: rp->rc_flag |= RC_INETADDR; rp->rc_inetaddr = saddr->sin_addr.s_addr; break; case AF_ISO: default: rp->rc_flag |= RC_NAM; rp->rc_nam = m_copym(nam, 0, M_COPYALL, M_WAIT); break; }; rp->rc_proc = nd->nd_procnum; LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); rp->rc_flag &= ~RC_LOCKED; if (rp->rc_flag & RC_WANTED) { rp->rc_flag &= ~RC_WANTED; wakeup((caddr_t)rp); } return (RC_DOIT); } /* * Update a request cache entry after the rpc has been done */ void nfsrv_updatecache(nam, nd, repvalid, repmbuf) struct mbuf *nam; register struct nfsd *nd; int repvalid; struct mbuf *repmbuf; { register struct nfsrvcache *rp; if (nd->nd_nqlflag != NQL_NOVAL) return; loop: for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; rp = rp->rc_hash.le_next) { if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nam)) { if ((rp->rc_flag & RC_LOCKED) != 0) { rp->rc_flag |= RC_WANTED; (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); goto loop; } rp->rc_flag |= RC_LOCKED; rp->rc_state = RC_DONE; /* * If we have a valid reply update status and save * the reply for non-idempotent rpc's. */ if (repvalid && nonidempotent[nd->nd_procnum]) { if (repliesstatus[nd->nd_procnum]) { rp->rc_status = nd->nd_repstat; rp->rc_flag |= RC_REPSTATUS; } else { rp->rc_reply = m_copym(repmbuf, 0, M_COPYALL, M_WAIT); rp->rc_flag |= RC_REPMBUF; } } rp->rc_flag &= ~RC_LOCKED; if (rp->rc_flag & RC_WANTED) { rp->rc_flag &= ~RC_WANTED; wakeup((caddr_t)rp); } return; } } } /* * Clean out the cache. Called when the last nfsd terminates. */ void nfsrv_cleancache() { register struct nfsrvcache *rp, *nextrp; for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { nextrp = rp->rc_lru.tqe_next; LIST_REMOVE(rp, rc_hash); TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); free(rp, M_NFSD); } numnfsrvcache = 0; }