1 /* $NetBSD: nfs_srvcache.c,v 1.12 1996/02/18 11:53:49 fvdl Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)nfs_srvcache.c 8.3 (Berkeley) 3/30/95 39 */ 40 41 /* 42 * Reference: Chet Juszczak, "Improving the Performance and Correctness 43 * of an NFS Server", in Proc. Winter 1989 USENIX Conference, 44 * pages 53-63. San Diego, February 1989. 45 */ 46 #include <sys/param.h> 47 #include <sys/vnode.h> 48 #include <sys/mount.h> 49 #include <sys/kernel.h> 50 #include <sys/systm.h> 51 #include <sys/proc.h> 52 #include <sys/mbuf.h> 53 #include <sys/malloc.h> 54 #include <sys/socket.h> 55 #include <sys/socketvar.h> 56 57 #include <netinet/in.h> 58 #ifdef ISO 59 #include <netiso/iso.h> 60 #endif 61 #include <nfs/nfsm_subs.h> 62 #include <nfs/rpcv2.h> 63 #include <nfs/nfsproto.h> 64 #include <nfs/nfs.h> 65 #include <nfs/nfsrvcache.h> 66 #include <nfs/nqnfs.h> 67 #include <nfs/nfs_var.h> 68 69 extern struct nfsstats nfsstats; 70 extern int nfsv2_procid[NFS_NPROCS]; 71 long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; 72 73 #define NFSRCHASH(xid) \ 74 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 75 LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 76 TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 77 u_long nfsrvhash; 78 79 #define TRUE 1 80 #define FALSE 0 81 82 #define NETFAMILY(rp) \ 83 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 84 85 /* 86 * Static array that defines which nfs rpc's are nonidempotent 87 */ 88 int nonidempotent[NFS_NPROCS] = { 89 FALSE, 90 FALSE, 91 TRUE, 92 FALSE, 93 FALSE, 94 FALSE, 95 FALSE, 96 TRUE, 97 TRUE, 98 TRUE, 99 TRUE, 100 TRUE, 101 TRUE, 102 TRUE, 103 TRUE, 104 TRUE, 105 FALSE, 106 FALSE, 107 FALSE, 108 FALSE, 109 FALSE, 110 FALSE, 111 FALSE, 112 FALSE, 113 FALSE, 114 FALSE, 115 }; 116 117 /* True iff the rpc reply is an nfs status ONLY! */ 118 static int nfsv2_repstat[NFS_NPROCS] = { 119 FALSE, 120 FALSE, 121 FALSE, 122 FALSE, 123 FALSE, 124 FALSE, 125 FALSE, 126 FALSE, 127 FALSE, 128 FALSE, 129 TRUE, 130 TRUE, 131 TRUE, 132 TRUE, 133 FALSE, 134 TRUE, 135 FALSE, 136 FALSE, 137 }; 138 139 /* 140 * Initialize the server request cache list 141 */ 142 void 143 nfsrv_initcache() 144 { 145 146 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash); 147 TAILQ_INIT(&nfsrvlruhead); 148 } 149 150 /* 151 * Look for the request in the cache 152 * If found then 153 * return action and optionally reply 154 * else 155 * insert it in the cache 156 * 157 * The rules are as follows: 158 * - if in progress, return DROP request 159 * - if completed within DELAY of the current time, return DROP it 160 * - if completed a longer time ago return REPLY if the reply was cached or 161 * return DOIT 162 * Update/add new request at end of lru list 163 */ 164 int 165 nfsrv_getcache(nd, slp, repp) 166 register struct nfsrv_descript *nd; 167 struct nfssvc_sock *slp; 168 struct mbuf **repp; 169 { 170 register struct nfsrvcache *rp; 171 struct mbuf *mb; 172 struct sockaddr_in *saddr; 173 caddr_t bpos; 174 int ret; 175 176 /* 177 * Don't cache recent requests for reliable transport protocols. 178 * (Maybe we should for the case of a reconnect, but..) 179 */ 180 if (!nd->nd_nam2) 181 return (RC_DOIT); 182 loop: 183 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 184 rp = rp->rc_hash.le_next) { 185 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 186 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 187 if ((rp->rc_flag & RC_LOCKED) != 0) { 188 rp->rc_flag |= RC_WANTED; 189 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 190 goto loop; 191 } 192 rp->rc_flag |= RC_LOCKED; 193 /* If not at end of LRU chain, move it there */ 194 if (rp->rc_lru.tqe_next) { 195 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 196 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 197 } 198 if (rp->rc_state == RC_UNUSED) 199 panic("nfsrv cache"); 200 if (rp->rc_state == RC_INPROG) { 201 nfsstats.srvcache_inproghits++; 202 ret = RC_DROPIT; 203 } else if (rp->rc_flag & RC_REPSTATUS) { 204 nfsstats.srvcache_nonidemdonehits++; 205 nfs_rephead(0, nd, slp, rp->rc_status, 206 0, (u_quad_t *)0, repp, &mb, &bpos); 207 ret = RC_REPLY; 208 } else if (rp->rc_flag & RC_REPMBUF) { 209 nfsstats.srvcache_nonidemdonehits++; 210 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 211 M_WAIT); 212 ret = RC_REPLY; 213 } else { 214 nfsstats.srvcache_idemdonehits++; 215 rp->rc_state = RC_INPROG; 216 ret = RC_DOIT; 217 } 218 rp->rc_flag &= ~RC_LOCKED; 219 if (rp->rc_flag & RC_WANTED) { 220 rp->rc_flag &= ~RC_WANTED; 221 wakeup((caddr_t)rp); 222 } 223 return (ret); 224 } 225 } 226 nfsstats.srvcache_misses++; 227 if (numnfsrvcache < desirednfsrvcache) { 228 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 229 M_NFSD, M_WAITOK); 230 bzero((char *)rp, sizeof *rp); 231 numnfsrvcache++; 232 rp->rc_flag = RC_LOCKED; 233 } else { 234 rp = nfsrvlruhead.tqh_first; 235 while ((rp->rc_flag & RC_LOCKED) != 0) { 236 rp->rc_flag |= RC_WANTED; 237 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 238 rp = nfsrvlruhead.tqh_first; 239 } 240 rp->rc_flag |= RC_LOCKED; 241 LIST_REMOVE(rp, rc_hash); 242 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 243 if (rp->rc_flag & RC_REPMBUF) 244 m_freem(rp->rc_reply); 245 if (rp->rc_flag & RC_NAM) 246 MFREE(rp->rc_nam, mb); 247 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 248 } 249 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 250 rp->rc_state = RC_INPROG; 251 rp->rc_xid = nd->nd_retxid; 252 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 253 switch (saddr->sin_family) { 254 case AF_INET: 255 rp->rc_flag |= RC_INETADDR; 256 rp->rc_inetaddr = saddr->sin_addr.s_addr; 257 break; 258 case AF_ISO: 259 default: 260 rp->rc_flag |= RC_NAM; 261 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 262 break; 263 }; 264 rp->rc_proc = nd->nd_procnum; 265 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 266 rp->rc_flag &= ~RC_LOCKED; 267 if (rp->rc_flag & RC_WANTED) { 268 rp->rc_flag &= ~RC_WANTED; 269 wakeup((caddr_t)rp); 270 } 271 return (RC_DOIT); 272 } 273 274 /* 275 * Update a request cache entry after the rpc has been done 276 */ 277 void 278 nfsrv_updatecache(nd, repvalid, repmbuf) 279 register struct nfsrv_descript *nd; 280 int repvalid; 281 struct mbuf *repmbuf; 282 { 283 register struct nfsrvcache *rp; 284 285 if (!nd->nd_nam2) 286 return; 287 loop: 288 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 289 rp = rp->rc_hash.le_next) { 290 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 291 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 292 if ((rp->rc_flag & RC_LOCKED) != 0) { 293 rp->rc_flag |= RC_WANTED; 294 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 295 goto loop; 296 } 297 rp->rc_flag |= RC_LOCKED; 298 rp->rc_state = RC_DONE; 299 /* 300 * If we have a valid reply update status and save 301 * the reply for non-idempotent rpc's. 302 */ 303 if (repvalid && nonidempotent[nd->nd_procnum]) { 304 if ((nd->nd_flag & ND_NFSV3) == 0 && 305 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 306 rp->rc_status = nd->nd_repstat; 307 rp->rc_flag |= RC_REPSTATUS; 308 } else { 309 rp->rc_reply = m_copym(repmbuf, 310 0, M_COPYALL, M_WAIT); 311 rp->rc_flag |= RC_REPMBUF; 312 } 313 } 314 rp->rc_flag &= ~RC_LOCKED; 315 if (rp->rc_flag & RC_WANTED) { 316 rp->rc_flag &= ~RC_WANTED; 317 wakeup((caddr_t)rp); 318 } 319 return; 320 } 321 } 322 } 323 324 /* 325 * Clean out the cache. Called when the last nfsd terminates. 326 */ 327 void 328 nfsrv_cleancache() 329 { 330 register struct nfsrvcache *rp, *nextrp; 331 332 for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { 333 nextrp = rp->rc_lru.tqe_next; 334 LIST_REMOVE(rp, rc_hash); 335 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 336 free(rp, M_NFSD); 337 } 338 numnfsrvcache = 0; 339 } 340