1 /* $OpenBSD: nfs_srvcache.c,v 1.10 2003/06/02 23:28:19 millert Exp $ */ 2 /* $NetBSD: nfs_srvcache.c,v 1.12 1996/02/18 11:53:49 fvdl Exp $ */ 3 4 /* 5 * Copyright (c) 1989, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Rick Macklem at The University of Guelph. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)nfs_srvcache.c 8.3 (Berkeley) 3/30/95 36 */ 37 38 /* 39 * Reference: Chet Juszczak, "Improving the Performance and Correctness 40 * of an NFS Server", in Proc. Winter 1989 USENIX Conference, 41 * pages 53-63. San Diego, February 1989. 42 */ 43 #include <sys/param.h> 44 #include <sys/vnode.h> 45 #include <sys/mount.h> 46 #include <sys/kernel.h> 47 #include <sys/systm.h> 48 #include <sys/proc.h> 49 #include <sys/mbuf.h> 50 #include <sys/malloc.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> 53 54 #include <netinet/in.h> 55 #ifdef ISO 56 #include <netiso/iso.h> 57 #endif 58 #include <nfs/nfsm_subs.h> 59 #include <nfs/rpcv2.h> 60 #include <nfs/nfsproto.h> 61 #include <nfs/nfs.h> 62 #include <nfs/nfsrvcache.h> 63 #include <nfs/nfs_var.h> 64 65 extern struct nfsstats nfsstats; 66 extern int nfsv2_procid[NFS_NPROCS]; 67 long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; 68 69 #define NFSRCHASH(xid) \ 70 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 71 LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 72 TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 73 u_long nfsrvhash; 74 75 #define TRUE 1 76 #define FALSE 0 77 78 #define NETFAMILY(rp) \ 79 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 80 81 /* 82 * Static array that defines which nfs rpc's are nonidempotent 83 */ 84 int nonidempotent[NFS_NPROCS] = { 85 FALSE, 86 FALSE, 87 TRUE, 88 FALSE, 89 FALSE, 90 FALSE, 91 FALSE, 92 TRUE, 93 TRUE, 94 TRUE, 95 TRUE, 96 TRUE, 97 TRUE, 98 TRUE, 99 TRUE, 100 TRUE, 101 FALSE, 102 FALSE, 103 FALSE, 104 FALSE, 105 FALSE, 106 FALSE, 107 FALSE, 108 FALSE, 109 FALSE, 110 FALSE, 111 }; 112 113 /* True iff the rpc reply is an nfs status ONLY! */ 114 static int nfsv2_repstat[NFS_NPROCS] = { 115 FALSE, 116 FALSE, 117 FALSE, 118 FALSE, 119 FALSE, 120 FALSE, 121 FALSE, 122 FALSE, 123 FALSE, 124 FALSE, 125 TRUE, 126 TRUE, 127 TRUE, 128 TRUE, 129 FALSE, 130 TRUE, 131 FALSE, 132 FALSE, 133 }; 134 135 /* 136 * Initialize the server request cache list 137 */ 138 void 139 nfsrv_initcache() 140 { 141 142 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, M_WAITOK, &nfsrvhash); 143 TAILQ_INIT(&nfsrvlruhead); 144 } 145 146 /* 147 * Look for the request in the cache 148 * If found then 149 * return action and optionally reply 150 * else 151 * insert it in the cache 152 * 153 * The rules are as follows: 154 * - if in progress, return DROP request 155 * - if completed within DELAY of the current time, return DROP it 156 * - if completed a longer time ago return REPLY if the reply was cached or 157 * return DOIT 158 * Update/add new request at end of lru list 159 */ 160 int 161 nfsrv_getcache(nd, slp, repp) 162 struct nfsrv_descript *nd; 163 struct nfssvc_sock *slp; 164 struct mbuf **repp; 165 { 166 struct nfsrvcache *rp; 167 struct mbuf *mb; 168 struct sockaddr_in *saddr; 169 caddr_t bpos; 170 int ret; 171 172 /* 173 * Don't cache recent requests for reliable transport protocols. 174 * (Maybe we should for the case of a reconnect, but..) 175 */ 176 if (!nd->nd_nam2) 177 return (RC_DOIT); 178 loop: 179 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != NULL; 180 rp = LIST_NEXT(rp, rc_hash)) { 181 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 182 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 183 if ((rp->rc_flag & RC_LOCKED) != 0) { 184 rp->rc_flag |= RC_WANTED; 185 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 186 goto loop; 187 } 188 rp->rc_flag |= RC_LOCKED; 189 /* If not at end of LRU chain, move it there */ 190 if (TAILQ_NEXT(rp, rc_lru)) { 191 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 192 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 193 } 194 if (rp->rc_state == RC_UNUSED) 195 panic("nfsrv cache"); 196 if (rp->rc_state == RC_INPROG) { 197 nfsstats.srvcache_inproghits++; 198 ret = RC_DROPIT; 199 } else if (rp->rc_flag & RC_REPSTATUS) { 200 nfsstats.srvcache_nonidemdonehits++; 201 nfs_rephead(0, nd, slp, rp->rc_status, 202 (u_quad_t *)0, repp, &mb, &bpos); 203 ret = RC_REPLY; 204 } else if (rp->rc_flag & RC_REPMBUF) { 205 nfsstats.srvcache_nonidemdonehits++; 206 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 207 M_WAIT); 208 ret = RC_REPLY; 209 } else { 210 nfsstats.srvcache_idemdonehits++; 211 rp->rc_state = RC_INPROG; 212 ret = RC_DOIT; 213 } 214 rp->rc_flag &= ~RC_LOCKED; 215 if (rp->rc_flag & RC_WANTED) { 216 rp->rc_flag &= ~RC_WANTED; 217 wakeup((caddr_t)rp); 218 } 219 return (ret); 220 } 221 } 222 nfsstats.srvcache_misses++; 223 if (numnfsrvcache < desirednfsrvcache) { 224 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 225 M_NFSD, M_WAITOK); 226 bzero((char *)rp, sizeof *rp); 227 numnfsrvcache++; 228 rp->rc_flag = RC_LOCKED; 229 } else { 230 rp = TAILQ_FIRST(&nfsrvlruhead); 231 while ((rp->rc_flag & RC_LOCKED) != 0) { 232 rp->rc_flag |= RC_WANTED; 233 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 234 rp = TAILQ_FIRST(&nfsrvlruhead); 235 } 236 rp->rc_flag |= RC_LOCKED; 237 LIST_REMOVE(rp, rc_hash); 238 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 239 if (rp->rc_flag & RC_REPMBUF) 240 m_freem(rp->rc_reply); 241 if (rp->rc_flag & RC_NAM) 242 MFREE(rp->rc_nam, mb); 243 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 244 } 245 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 246 rp->rc_state = RC_INPROG; 247 rp->rc_xid = nd->nd_retxid; 248 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 249 switch (saddr->sin_family) { 250 case AF_INET: 251 rp->rc_flag |= RC_INETADDR; 252 rp->rc_inetaddr = saddr->sin_addr.s_addr; 253 break; 254 case AF_ISO: 255 default: 256 rp->rc_flag |= RC_NAM; 257 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 258 break; 259 }; 260 rp->rc_proc = nd->nd_procnum; 261 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 262 rp->rc_flag &= ~RC_LOCKED; 263 if (rp->rc_flag & RC_WANTED) { 264 rp->rc_flag &= ~RC_WANTED; 265 wakeup((caddr_t)rp); 266 } 267 return (RC_DOIT); 268 } 269 270 /* 271 * Update a request cache entry after the rpc has been done 272 */ 273 void 274 nfsrv_updatecache(nd, repvalid, repmbuf) 275 struct nfsrv_descript *nd; 276 int repvalid; 277 struct mbuf *repmbuf; 278 { 279 struct nfsrvcache *rp; 280 281 if (!nd->nd_nam2) 282 return; 283 loop: 284 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != NULL; 285 rp = LIST_NEXT(rp, rc_hash)) { 286 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 287 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 288 if ((rp->rc_flag & RC_LOCKED) != 0) { 289 rp->rc_flag |= RC_WANTED; 290 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 291 goto loop; 292 } 293 rp->rc_flag |= RC_LOCKED; 294 rp->rc_state = RC_DONE; 295 /* 296 * If we have a valid reply update status and save 297 * the reply for non-idempotent rpc's. 298 */ 299 if (repvalid && nonidempotent[nd->nd_procnum]) { 300 if ((nd->nd_flag & ND_NFSV3) == 0 && 301 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 302 rp->rc_status = nd->nd_repstat; 303 rp->rc_flag |= RC_REPSTATUS; 304 } else { 305 rp->rc_reply = m_copym(repmbuf, 306 0, M_COPYALL, M_WAIT); 307 rp->rc_flag |= RC_REPMBUF; 308 } 309 } 310 rp->rc_flag &= ~RC_LOCKED; 311 if (rp->rc_flag & RC_WANTED) { 312 rp->rc_flag &= ~RC_WANTED; 313 wakeup((caddr_t)rp); 314 } 315 return; 316 } 317 } 318 } 319 320 /* 321 * Clean out the cache. Called when the last nfsd terminates. 322 */ 323 void 324 nfsrv_cleancache() 325 { 326 struct nfsrvcache *rp, *nextrp; 327 328 for (rp = TAILQ_FIRST(&nfsrvlruhead); rp != NULL; rp = nextrp) { 329 nextrp = TAILQ_NEXT(rp, rc_lru); 330 LIST_REMOVE(rp, rc_hash); 331 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 332 free(rp, M_NFSD); 333 } 334 numnfsrvcache = 0; 335 } 336