nfs_srvcache.c revision 1.8
1 /* $NetBSD: nfs_srvcache.c,v 1.8 1994/06/29 06:42:19 cgd 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 8.1 (Berkeley) 6/10/93 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) (((xid) + ((xid) >> 24)) & rheadhash) 71 static struct nfsrvcache *nfsrvlruhead, **nfsrvlrutail = &nfsrvlruhead; 72 static struct nfsrvcache **rheadhtbl; 73 static u_long rheadhash; 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 FALSE, 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 }; 109 110 /* True iff the rpc reply is an nfs status ONLY! */ 111 static int repliesstatus[NFS_NPROCS] = { 112 FALSE, 113 FALSE, 114 FALSE, 115 FALSE, 116 FALSE, 117 FALSE, 118 FALSE, 119 FALSE, 120 FALSE, 121 FALSE, 122 TRUE, 123 TRUE, 124 TRUE, 125 TRUE, 126 FALSE, 127 TRUE, 128 FALSE, 129 FALSE, 130 FALSE, 131 FALSE, 132 FALSE, 133 FALSE, 134 TRUE, 135 }; 136 137 /* 138 * Initialize the server request cache list 139 */ 140 nfsrv_initcache() 141 { 142 143 rheadhtbl = hashinit(desirednfsrvcache, M_NFSD, &rheadhash); 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 nfsrv_getcache(nam, nd, repp) 161 struct mbuf *nam; 162 register struct nfsd *nd; 163 struct mbuf **repp; 164 { 165 register struct nfsrvcache *rp, *rq, **rpp; 166 struct mbuf *mb; 167 struct sockaddr_in *saddr; 168 caddr_t bpos; 169 int ret; 170 171 if (nd->nd_nqlflag != NQL_NOVAL) 172 return (RC_DOIT); 173 rpp = &rheadhtbl[NFSRCHASH(nd->nd_retxid)]; 174 loop: 175 for (rp = *rpp; rp; rp = rp->rc_forw) { 176 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 177 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nam)) { 178 if ((rp->rc_flag & RC_LOCKED) != 0) { 179 rp->rc_flag |= RC_WANTED; 180 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 181 goto loop; 182 } 183 rp->rc_flag |= RC_LOCKED; 184 /* If not at end of LRU chain, move it there */ 185 if (rp->rc_next) { 186 /* remove from LRU chain */ 187 *rp->rc_prev = rp->rc_next; 188 rp->rc_next->rc_prev = rp->rc_prev; 189 /* and replace at end of it */ 190 rp->rc_next = NULL; 191 rp->rc_prev = nfsrvlrutail; 192 *nfsrvlrutail = rp; 193 nfsrvlrutail = &rp->rc_next; 194 } 195 if (rp->rc_state == RC_UNUSED) 196 panic("nfsrv cache"); 197 if (rp->rc_state == RC_INPROG) { 198 nfsstats.srvcache_inproghits++; 199 ret = RC_DROPIT; 200 } else if (rp->rc_flag & RC_REPSTATUS) { 201 nfsstats.srvcache_nonidemdonehits++; 202 nfs_rephead(0, nd, rp->rc_status, 203 0, (u_quad_t *)0, repp, &mb, &bpos); 204 ret = RC_REPLY; 205 } else if (rp->rc_flag & RC_REPMBUF) { 206 nfsstats.srvcache_nonidemdonehits++; 207 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 208 M_WAIT); 209 ret = RC_REPLY; 210 } else { 211 nfsstats.srvcache_idemdonehits++; 212 rp->rc_state = RC_INPROG; 213 ret = RC_DOIT; 214 } 215 rp->rc_flag &= ~RC_LOCKED; 216 if (rp->rc_flag & RC_WANTED) { 217 rp->rc_flag &= ~RC_WANTED; 218 wakeup((caddr_t)rp); 219 } 220 return (ret); 221 } 222 } 223 nfsstats.srvcache_misses++; 224 if (numnfsrvcache < desirednfsrvcache) { 225 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 226 M_NFSD, M_WAITOK); 227 bzero((char *)rp, sizeof *rp); 228 numnfsrvcache++; 229 rp->rc_flag = RC_LOCKED; 230 } else { 231 rp = nfsrvlruhead; 232 while ((rp->rc_flag & RC_LOCKED) != 0) { 233 rp->rc_flag |= RC_WANTED; 234 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 235 rp = nfsrvlruhead; 236 } 237 rp->rc_flag |= RC_LOCKED; 238 /* remove from hash chain */ 239 if (rq = rp->rc_forw) 240 rq->rc_back = rp->rc_back; 241 *rp->rc_back = rq; 242 /* remove from LRU chain */ 243 *rp->rc_prev = rp->rc_next; 244 rp->rc_next->rc_prev = rp->rc_prev; 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 /* place at end of LRU list */ 252 rp->rc_next = NULL; 253 rp->rc_prev = nfsrvlrutail; 254 *nfsrvlrutail = rp; 255 nfsrvlrutail = &rp->rc_next; 256 rp->rc_state = RC_INPROG; 257 rp->rc_xid = nd->nd_retxid; 258 saddr = mtod(nam, struct sockaddr_in *); 259 switch (saddr->sin_family) { 260 case AF_INET: 261 rp->rc_flag |= RC_INETADDR; 262 rp->rc_inetaddr = saddr->sin_addr.s_addr; 263 break; 264 case AF_ISO: 265 default: 266 rp->rc_flag |= RC_NAM; 267 rp->rc_nam = m_copym(nam, 0, M_COPYALL, M_WAIT); 268 break; 269 }; 270 rp->rc_proc = nd->nd_procnum; 271 /* insert into hash chain */ 272 if (rq = *rpp) 273 rq->rc_back = &rp->rc_forw; 274 rp->rc_forw = rq; 275 rp->rc_back = rpp; 276 *rpp = rp; 277 rp->rc_flag &= ~RC_LOCKED; 278 if (rp->rc_flag & RC_WANTED) { 279 rp->rc_flag &= ~RC_WANTED; 280 wakeup((caddr_t)rp); 281 } 282 return (RC_DOIT); 283 } 284 285 /* 286 * Update a request cache entry after the rpc has been done 287 */ 288 void 289 nfsrv_updatecache(nam, nd, repvalid, repmbuf) 290 struct mbuf *nam; 291 register struct nfsd *nd; 292 int repvalid; 293 struct mbuf *repmbuf; 294 { 295 register struct nfsrvcache *rp; 296 297 if (nd->nd_nqlflag != NQL_NOVAL) 298 return; 299 loop: 300 for (rp = rheadhtbl[NFSRCHASH(nd->nd_retxid)]; rp; rp = rp->rc_forw) { 301 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 302 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nam)) { 303 if ((rp->rc_flag & RC_LOCKED) != 0) { 304 rp->rc_flag |= RC_WANTED; 305 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 306 goto loop; 307 } 308 rp->rc_flag |= RC_LOCKED; 309 rp->rc_state = RC_DONE; 310 /* 311 * If we have a valid reply update status and save 312 * the reply for non-idempotent rpc's. 313 */ 314 if (repvalid && nonidempotent[nd->nd_procnum]) { 315 if (repliesstatus[nd->nd_procnum]) { 316 rp->rc_status = nd->nd_repstat; 317 rp->rc_flag |= RC_REPSTATUS; 318 } else { 319 rp->rc_reply = m_copym(repmbuf, 320 0, M_COPYALL, M_WAIT); 321 rp->rc_flag |= RC_REPMBUF; 322 } 323 } 324 rp->rc_flag &= ~RC_LOCKED; 325 if (rp->rc_flag & RC_WANTED) { 326 rp->rc_flag &= ~RC_WANTED; 327 wakeup((caddr_t)rp); 328 } 329 return; 330 } 331 } 332 } 333 334 /* 335 * Clean out the cache. Called when the last nfsd terminates. 336 */ 337 void 338 nfsrv_cleancache() 339 { 340 register struct nfsrvcache *rp, *nextrp; 341 342 for (rp = nfsrvlruhead; rp; rp = nextrp) { 343 nextrp = rp->rc_next; 344 free(rp, M_NFSD); 345 } 346 bzero((char *)rheadhtbl, (rheadhash + 1) * sizeof(void *)); 347 nfsrvlruhead = NULL; 348 nfsrvlrutail = &nfsrvlruhead; 349 numnfsrvcache = 0; 350 } 351
Indexes created Tue Sep 23 07:09:52 GMT 2025