1 /* $NetBSD: nfs_srvcache.c,v 1.10 1994/12/13 17:17:03 mycroft 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 8.2 (Berkeley) 8/18/94 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/nfsv2.h> 64 #include <nfs/nfs.h> 65 #include <nfs/nfsrvcache.h> 66 #include <nfs/nqnfs.h> 67 68 long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; 69 70 #define NFSRCHASH(xid) \ 71 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 72 LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 73 TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 74 u_long nfsrvhash; 75 76 #define TRUE 1 77 #define FALSE 0 78 79 #define NETFAMILY(rp) \ 80 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 81 82 /* 83 * Static array that defines which nfs rpc's are nonidempotent 84 */ 85 int nonidempotent[NFS_NPROCS] = { 86 FALSE, 87 FALSE, 88 TRUE, 89 FALSE, 90 FALSE, 91 FALSE, 92 FALSE, 93 FALSE, 94 TRUE, 95 TRUE, 96 TRUE, 97 TRUE, 98 TRUE, 99 TRUE, 100 TRUE, 101 TRUE, 102 FALSE, 103 FALSE, 104 FALSE, 105 FALSE, 106 FALSE, 107 FALSE, 108 FALSE, 109 }; 110 111 /* True iff the rpc reply is an nfs status ONLY! */ 112 static int repliesstatus[NFS_NPROCS] = { 113 FALSE, 114 FALSE, 115 FALSE, 116 FALSE, 117 FALSE, 118 FALSE, 119 FALSE, 120 FALSE, 121 FALSE, 122 FALSE, 123 TRUE, 124 TRUE, 125 TRUE, 126 TRUE, 127 FALSE, 128 TRUE, 129 FALSE, 130 FALSE, 131 FALSE, 132 FALSE, 133 FALSE, 134 FALSE, 135 TRUE, 136 }; 137 138 /* 139 * Initialize the server request cache list 140 */ 141 nfsrv_initcache() 142 { 143 144 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash); 145 TAILQ_INIT(&nfsrvlruhead); 146 } 147 148 /* 149 * Look for the request in the cache 150 * If found then 151 * return action and optionally reply 152 * else 153 * insert it in the cache 154 * 155 * The rules are as follows: 156 * - if in progress, return DROP request 157 * - if completed within DELAY of the current time, return DROP it 158 * - if completed a longer time ago return REPLY if the reply was cached or 159 * return DOIT 160 * Update/add new request at end of lru list 161 */ 162 nfsrv_getcache(nam, nd, repp) 163 struct mbuf *nam; 164 register struct nfsd *nd; 165 struct mbuf **repp; 166 { 167 register struct nfsrvcache *rp; 168 struct mbuf *mb; 169 struct sockaddr_in *saddr; 170 caddr_t bpos; 171 int ret; 172 173 if (nd->nd_nqlflag != NQL_NOVAL) 174 return (RC_DOIT); 175 loop: 176 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 177 rp = rp->rc_hash.le_next) { 178 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 179 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nam)) { 180 if ((rp->rc_flag & RC_LOCKED) != 0) { 181 rp->rc_flag |= RC_WANTED; 182 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 183 goto loop; 184 } 185 rp->rc_flag |= RC_LOCKED; 186 /* If not at end of LRU chain, move it there */ 187 if (rp->rc_lru.tqe_next) { 188 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 189 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 190 } 191 if (rp->rc_state == RC_UNUSED) 192 panic("nfsrv cache"); 193 if (rp->rc_state == RC_INPROG) { 194 nfsstats.srvcache_inproghits++; 195 ret = RC_DROPIT; 196 } else if (rp->rc_flag & RC_REPSTATUS) { 197 nfsstats.srvcache_nonidemdonehits++; 198 nfs_rephead(0, nd, rp->rc_status, 199 0, (u_quad_t *)0, repp, &mb, &bpos); 200 ret = RC_REPLY; 201 } else if (rp->rc_flag & RC_REPMBUF) { 202 nfsstats.srvcache_nonidemdonehits++; 203 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 204 M_WAIT); 205 ret = RC_REPLY; 206 } else { 207 nfsstats.srvcache_idemdonehits++; 208 rp->rc_state = RC_INPROG; 209 ret = RC_DOIT; 210 } 211 rp->rc_flag &= ~RC_LOCKED; 212 if (rp->rc_flag & RC_WANTED) { 213 rp->rc_flag &= ~RC_WANTED; 214 wakeup((caddr_t)rp); 215 } 216 return (ret); 217 } 218 } 219 nfsstats.srvcache_misses++; 220 if (numnfsrvcache < desirednfsrvcache) { 221 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 222 M_NFSD, M_WAITOK); 223 bzero((char *)rp, sizeof *rp); 224 numnfsrvcache++; 225 rp->rc_flag = RC_LOCKED; 226 } else { 227 rp = nfsrvlruhead.tqh_first; 228 while ((rp->rc_flag & RC_LOCKED) != 0) { 229 rp->rc_flag |= RC_WANTED; 230 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 231 rp = nfsrvlruhead.tqh_first; 232 } 233 rp->rc_flag |= RC_LOCKED; 234 LIST_REMOVE(rp, rc_hash); 235 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 236 if (rp->rc_flag & RC_REPMBUF) 237 m_freem(rp->rc_reply); 238 if (rp->rc_flag & RC_NAM) 239 MFREE(rp->rc_nam, mb); 240 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 241 } 242 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 243 rp->rc_state = RC_INPROG; 244 rp->rc_xid = nd->nd_retxid; 245 saddr = mtod(nam, struct sockaddr_in *); 246 switch (saddr->sin_family) { 247 case AF_INET: 248 rp->rc_flag |= RC_INETADDR; 249 rp->rc_inetaddr = saddr->sin_addr.s_addr; 250 break; 251 case AF_ISO: 252 default: 253 rp->rc_flag |= RC_NAM; 254 rp->rc_nam = m_copym(nam, 0, M_COPYALL, M_WAIT); 255 break; 256 }; 257 rp->rc_proc = nd->nd_procnum; 258 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 259 rp->rc_flag &= ~RC_LOCKED; 260 if (rp->rc_flag & RC_WANTED) { 261 rp->rc_flag &= ~RC_WANTED; 262 wakeup((caddr_t)rp); 263 } 264 return (RC_DOIT); 265 } 266 267 /* 268 * Update a request cache entry after the rpc has been done 269 */ 270 void 271 nfsrv_updatecache(nam, nd, repvalid, repmbuf) 272 struct mbuf *nam; 273 register struct nfsd *nd; 274 int repvalid; 275 struct mbuf *repmbuf; 276 { 277 register struct nfsrvcache *rp; 278 279 if (nd->nd_nqlflag != NQL_NOVAL) 280 return; 281 loop: 282 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 283 rp = rp->rc_hash.le_next) { 284 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 285 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nam)) { 286 if ((rp->rc_flag & RC_LOCKED) != 0) { 287 rp->rc_flag |= RC_WANTED; 288 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 289 goto loop; 290 } 291 rp->rc_flag |= RC_LOCKED; 292 rp->rc_state = RC_DONE; 293 /* 294 * If we have a valid reply update status and save 295 * the reply for non-idempotent rpc's. 296 */ 297 if (repvalid && nonidempotent[nd->nd_procnum]) { 298 if (repliesstatus[nd->nd_procnum]) { 299 rp->rc_status = nd->nd_repstat; 300 rp->rc_flag |= RC_REPSTATUS; 301 } else { 302 rp->rc_reply = m_copym(repmbuf, 303 0, M_COPYALL, M_WAIT); 304 rp->rc_flag |= RC_REPMBUF; 305 } 306 } 307 rp->rc_flag &= ~RC_LOCKED; 308 if (rp->rc_flag & RC_WANTED) { 309 rp->rc_flag &= ~RC_WANTED; 310 wakeup((caddr_t)rp); 311 } 312 return; 313 } 314 } 315 } 316 317 /* 318 * Clean out the cache. Called when the last nfsd terminates. 319 */ 320 void 321 nfsrv_cleancache() 322 { 323 register struct nfsrvcache *rp, *nextrp; 324 325 for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { 326 nextrp = rp->rc_lru.tqe_next; 327 LIST_REMOVE(rp, rc_hash); 328 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 329 free(rp, M_NFSD); 330 } 331 numnfsrvcache = 0; 332 } 333