1 /* $NetBSD: nfs_srvcache.c,v 1.18 2001/02/21 21:39:58 jdolecek 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 const 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 const 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, HASH_LIST, M_NFSD, 149 M_WAITOK, &nfsrvhash); 150 TAILQ_INIT(&nfsrvlruhead); 151 } 152 153 /* 154 * Look for the request in the cache 155 * If found then 156 * return action and optionally reply 157 * else 158 * insert it in the cache 159 * 160 * The rules are as follows: 161 * - if in progress, return DROP request 162 * - if completed within DELAY of the current time, return DROP it 163 * - if completed a longer time ago return REPLY if the reply was cached or 164 * return DOIT 165 * Update/add new request at end of lru list 166 */ 167 int 168 nfsrv_getcache(nd, slp, repp) 169 struct nfsrv_descript *nd; 170 struct nfssvc_sock *slp; 171 struct mbuf **repp; 172 { 173 struct nfsrvcache *rp; 174 struct mbuf *mb; 175 struct sockaddr_in *saddr; 176 caddr_t bpos; 177 int ret; 178 179 /* 180 * Don't cache recent requests for reliable transport protocols. 181 * (Maybe we should for the case of a reconnect, but..) 182 */ 183 if (!nd->nd_nam2) 184 return (RC_DOIT); 185 loop: 186 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 187 rp = rp->rc_hash.le_next) { 188 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 189 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 190 if ((rp->rc_flag & RC_LOCKED) != 0) { 191 rp->rc_flag |= RC_WANTED; 192 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 193 goto loop; 194 } 195 rp->rc_flag |= RC_LOCKED; 196 /* If not at end of LRU chain, move it there */ 197 if (rp->rc_lru.tqe_next) { 198 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 199 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 200 } 201 if (rp->rc_state == RC_UNUSED) 202 panic("nfsrv cache"); 203 if (rp->rc_state == RC_INPROG) { 204 nfsstats.srvcache_inproghits++; 205 ret = RC_DROPIT; 206 } else if (rp->rc_flag & RC_REPSTATUS) { 207 nfsstats.srvcache_nonidemdonehits++; 208 nfs_rephead(0, nd, slp, rp->rc_status, 209 0, (u_quad_t *)0, repp, &mb, &bpos); 210 ret = RC_REPLY; 211 } else if (rp->rc_flag & RC_REPMBUF) { 212 nfsstats.srvcache_nonidemdonehits++; 213 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 214 M_WAIT); 215 ret = RC_REPLY; 216 } else { 217 nfsstats.srvcache_idemdonehits++; 218 rp->rc_state = RC_INPROG; 219 ret = RC_DOIT; 220 } 221 rp->rc_flag &= ~RC_LOCKED; 222 if (rp->rc_flag & RC_WANTED) { 223 rp->rc_flag &= ~RC_WANTED; 224 wakeup((caddr_t)rp); 225 } 226 return (ret); 227 } 228 } 229 nfsstats.srvcache_misses++; 230 if (numnfsrvcache < desirednfsrvcache) { 231 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 232 M_NFSD, M_WAITOK); 233 memset((char *)rp, 0, sizeof *rp); 234 numnfsrvcache++; 235 rp->rc_flag = RC_LOCKED; 236 } else { 237 rp = nfsrvlruhead.tqh_first; 238 while ((rp->rc_flag & RC_LOCKED) != 0) { 239 rp->rc_flag |= RC_WANTED; 240 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 241 rp = nfsrvlruhead.tqh_first; 242 } 243 rp->rc_flag |= RC_LOCKED; 244 LIST_REMOVE(rp, rc_hash); 245 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 246 if (rp->rc_flag & RC_REPMBUF) 247 m_freem(rp->rc_reply); 248 if (rp->rc_flag & RC_NAM) 249 MFREE(rp->rc_nam, mb); 250 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 251 } 252 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 253 rp->rc_state = RC_INPROG; 254 rp->rc_xid = nd->nd_retxid; 255 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 256 switch (saddr->sin_family) { 257 case AF_INET: 258 rp->rc_flag |= RC_INETADDR; 259 rp->rc_inetaddr = saddr->sin_addr.s_addr; 260 break; 261 case AF_ISO: 262 default: 263 rp->rc_flag |= RC_NAM; 264 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 265 break; 266 }; 267 rp->rc_proc = nd->nd_procnum; 268 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 269 rp->rc_flag &= ~RC_LOCKED; 270 if (rp->rc_flag & RC_WANTED) { 271 rp->rc_flag &= ~RC_WANTED; 272 wakeup((caddr_t)rp); 273 } 274 return (RC_DOIT); 275 } 276 277 /* 278 * Update a request cache entry after the rpc has been done 279 */ 280 void 281 nfsrv_updatecache(nd, repvalid, repmbuf) 282 struct nfsrv_descript *nd; 283 int repvalid; 284 struct mbuf *repmbuf; 285 { 286 struct nfsrvcache *rp; 287 288 if (!nd->nd_nam2) 289 return; 290 loop: 291 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 292 rp = rp->rc_hash.le_next) { 293 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 294 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 295 if ((rp->rc_flag & RC_LOCKED) != 0) { 296 rp->rc_flag |= RC_WANTED; 297 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 298 goto loop; 299 } 300 rp->rc_flag |= RC_LOCKED; 301 rp->rc_state = RC_DONE; 302 /* 303 * If we have a valid reply update status and save 304 * the reply for non-idempotent rpc's. 305 */ 306 if (repvalid && nonidempotent[nd->nd_procnum]) { 307 if ((nd->nd_flag & ND_NFSV3) == 0 && 308 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 309 rp->rc_status = nd->nd_repstat; 310 rp->rc_flag |= RC_REPSTATUS; 311 } else { 312 rp->rc_reply = m_copym(repmbuf, 313 0, M_COPYALL, M_WAIT); 314 rp->rc_flag |= RC_REPMBUF; 315 } 316 } 317 rp->rc_flag &= ~RC_LOCKED; 318 if (rp->rc_flag & RC_WANTED) { 319 rp->rc_flag &= ~RC_WANTED; 320 wakeup((caddr_t)rp); 321 } 322 return; 323 } 324 } 325 } 326 327 /* 328 * Clean out the cache. Called when the last nfsd terminates. 329 */ 330 void 331 nfsrv_cleancache() 332 { 333 struct nfsrvcache *rp, *nextrp; 334 335 for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { 336 nextrp = rp->rc_lru.tqe_next; 337 LIST_REMOVE(rp, rc_hash); 338 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 339 free(rp, M_NFSD); 340 } 341 numnfsrvcache = 0; 342 } 343