1 /* $NetBSD: nfs_srvcache.c,v 1.16 2000/03/30 12:51:16 augustss 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 "opt_iso.h" 47 48 #include <sys/param.h> 49 #include <sys/vnode.h> 50 #include <sys/mount.h> 51 #include <sys/kernel.h> 52 #include <sys/systm.h> 53 #include <sys/proc.h> 54 #include <sys/mbuf.h> 55 #include <sys/malloc.h> 56 #include <sys/socket.h> 57 #include <sys/socketvar.h> 58 59 #include <netinet/in.h> 60 #ifdef ISO 61 #include <netiso/iso.h> 62 #endif 63 #include <nfs/nfsm_subs.h> 64 #include <nfs/rpcv2.h> 65 #include <nfs/nfsproto.h> 66 #include <nfs/nfs.h> 67 #include <nfs/nfsrvcache.h> 68 #include <nfs/nqnfs.h> 69 #include <nfs/nfs_var.h> 70 71 extern struct nfsstats nfsstats; 72 extern int nfsv2_procid[NFS_NPROCS]; 73 long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; 74 75 #define NFSRCHASH(xid) \ 76 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 77 LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 78 TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 79 u_long nfsrvhash; 80 81 #define TRUE 1 82 #define FALSE 0 83 84 #define NETFAMILY(rp) \ 85 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 86 87 /* 88 * Static array that defines which nfs rpc's are nonidempotent 89 */ 90 int nonidempotent[NFS_NPROCS] = { 91 FALSE, 92 FALSE, 93 TRUE, 94 FALSE, 95 FALSE, 96 FALSE, 97 FALSE, 98 TRUE, 99 TRUE, 100 TRUE, 101 TRUE, 102 TRUE, 103 TRUE, 104 TRUE, 105 TRUE, 106 TRUE, 107 FALSE, 108 FALSE, 109 FALSE, 110 FALSE, 111 FALSE, 112 FALSE, 113 FALSE, 114 FALSE, 115 FALSE, 116 FALSE, 117 }; 118 119 /* True iff the rpc reply is an nfs status ONLY! */ 120 static int nfsv2_repstat[NFS_NPROCS] = { 121 FALSE, 122 FALSE, 123 FALSE, 124 FALSE, 125 FALSE, 126 FALSE, 127 FALSE, 128 FALSE, 129 FALSE, 130 FALSE, 131 TRUE, 132 TRUE, 133 TRUE, 134 TRUE, 135 FALSE, 136 TRUE, 137 FALSE, 138 FALSE, 139 }; 140 141 /* 142 * Initialize the server request cache list 143 */ 144 void 145 nfsrv_initcache() 146 { 147 148 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, M_WAITOK, &nfsrvhash); 149 TAILQ_INIT(&nfsrvlruhead); 150 } 151 152 /* 153 * Look for the request in the cache 154 * If found then 155 * return action and optionally reply 156 * else 157 * insert it in the cache 158 * 159 * The rules are as follows: 160 * - if in progress, return DROP request 161 * - if completed within DELAY of the current time, return DROP it 162 * - if completed a longer time ago return REPLY if the reply was cached or 163 * return DOIT 164 * Update/add new request at end of lru list 165 */ 166 int 167 nfsrv_getcache(nd, slp, repp) 168 struct nfsrv_descript *nd; 169 struct nfssvc_sock *slp; 170 struct mbuf **repp; 171 { 172 struct nfsrvcache *rp; 173 struct mbuf *mb; 174 struct sockaddr_in *saddr; 175 caddr_t bpos; 176 int ret; 177 178 /* 179 * Don't cache recent requests for reliable transport protocols. 180 * (Maybe we should for the case of a reconnect, but..) 181 */ 182 if (!nd->nd_nam2) 183 return (RC_DOIT); 184 loop: 185 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 186 rp = rp->rc_hash.le_next) { 187 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 188 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 189 if ((rp->rc_flag & RC_LOCKED) != 0) { 190 rp->rc_flag |= RC_WANTED; 191 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 192 goto loop; 193 } 194 rp->rc_flag |= RC_LOCKED; 195 /* If not at end of LRU chain, move it there */ 196 if (rp->rc_lru.tqe_next) { 197 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 198 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 199 } 200 if (rp->rc_state == RC_UNUSED) 201 panic("nfsrv cache"); 202 if (rp->rc_state == RC_INPROG) { 203 nfsstats.srvcache_inproghits++; 204 ret = RC_DROPIT; 205 } else if (rp->rc_flag & RC_REPSTATUS) { 206 nfsstats.srvcache_nonidemdonehits++; 207 nfs_rephead(0, nd, slp, rp->rc_status, 208 0, (u_quad_t *)0, repp, &mb, &bpos); 209 ret = RC_REPLY; 210 } else if (rp->rc_flag & RC_REPMBUF) { 211 nfsstats.srvcache_nonidemdonehits++; 212 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 213 M_WAIT); 214 ret = RC_REPLY; 215 } else { 216 nfsstats.srvcache_idemdonehits++; 217 rp->rc_state = RC_INPROG; 218 ret = RC_DOIT; 219 } 220 rp->rc_flag &= ~RC_LOCKED; 221 if (rp->rc_flag & RC_WANTED) { 222 rp->rc_flag &= ~RC_WANTED; 223 wakeup((caddr_t)rp); 224 } 225 return (ret); 226 } 227 } 228 nfsstats.srvcache_misses++; 229 if (numnfsrvcache < desirednfsrvcache) { 230 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 231 M_NFSD, M_WAITOK); 232 memset((char *)rp, 0, sizeof *rp); 233 numnfsrvcache++; 234 rp->rc_flag = RC_LOCKED; 235 } else { 236 rp = nfsrvlruhead.tqh_first; 237 while ((rp->rc_flag & RC_LOCKED) != 0) { 238 rp->rc_flag |= RC_WANTED; 239 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 240 rp = nfsrvlruhead.tqh_first; 241 } 242 rp->rc_flag |= RC_LOCKED; 243 LIST_REMOVE(rp, rc_hash); 244 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 245 if (rp->rc_flag & RC_REPMBUF) 246 m_freem(rp->rc_reply); 247 if (rp->rc_flag & RC_NAM) 248 MFREE(rp->rc_nam, mb); 249 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 250 } 251 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 252 rp->rc_state = RC_INPROG; 253 rp->rc_xid = nd->nd_retxid; 254 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 255 switch (saddr->sin_family) { 256 case AF_INET: 257 rp->rc_flag |= RC_INETADDR; 258 rp->rc_inetaddr = saddr->sin_addr.s_addr; 259 break; 260 case AF_ISO: 261 default: 262 rp->rc_flag |= RC_NAM; 263 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 264 break; 265 }; 266 rp->rc_proc = nd->nd_procnum; 267 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 268 rp->rc_flag &= ~RC_LOCKED; 269 if (rp->rc_flag & RC_WANTED) { 270 rp->rc_flag &= ~RC_WANTED; 271 wakeup((caddr_t)rp); 272 } 273 return (RC_DOIT); 274 } 275 276 /* 277 * Update a request cache entry after the rpc has been done 278 */ 279 void 280 nfsrv_updatecache(nd, repvalid, repmbuf) 281 struct nfsrv_descript *nd; 282 int repvalid; 283 struct mbuf *repmbuf; 284 { 285 struct nfsrvcache *rp; 286 287 if (!nd->nd_nam2) 288 return; 289 loop: 290 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 291 rp = rp->rc_hash.le_next) { 292 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 293 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 294 if ((rp->rc_flag & RC_LOCKED) != 0) { 295 rp->rc_flag |= RC_WANTED; 296 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 297 goto loop; 298 } 299 rp->rc_flag |= RC_LOCKED; 300 rp->rc_state = RC_DONE; 301 /* 302 * If we have a valid reply update status and save 303 * the reply for non-idempotent rpc's. 304 */ 305 if (repvalid && nonidempotent[nd->nd_procnum]) { 306 if ((nd->nd_flag & ND_NFSV3) == 0 && 307 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 308 rp->rc_status = nd->nd_repstat; 309 rp->rc_flag |= RC_REPSTATUS; 310 } else { 311 rp->rc_reply = m_copym(repmbuf, 312 0, M_COPYALL, M_WAIT); 313 rp->rc_flag |= RC_REPMBUF; 314 } 315 } 316 rp->rc_flag &= ~RC_LOCKED; 317 if (rp->rc_flag & RC_WANTED) { 318 rp->rc_flag &= ~RC_WANTED; 319 wakeup((caddr_t)rp); 320 } 321 return; 322 } 323 } 324 } 325 326 /* 327 * Clean out the cache. Called when the last nfsd terminates. 328 */ 329 void 330 nfsrv_cleancache() 331 { 332 struct nfsrvcache *rp, *nextrp; 333 334 for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { 335 nextrp = rp->rc_lru.tqe_next; 336 LIST_REMOVE(rp, rc_hash); 337 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 338 free(rp, M_NFSD); 339 } 340 numnfsrvcache = 0; 341 } 342