1 /* $NetBSD: nfs_srvcache.c,v 1.19 2001/11/10 10:59:10 lukem 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 47 #include <sys/cdefs.h> 48 __KERNEL_RCSID(0, "$NetBSD: nfs_srvcache.c,v 1.19 2001/11/10 10:59:10 lukem Exp $"); 49 50 #include "opt_iso.h" 51 52 #include <sys/param.h> 53 #include <sys/vnode.h> 54 #include <sys/mount.h> 55 #include <sys/kernel.h> 56 #include <sys/systm.h> 57 #include <sys/proc.h> 58 #include <sys/mbuf.h> 59 #include <sys/malloc.h> 60 #include <sys/socket.h> 61 #include <sys/socketvar.h> 62 63 #include <netinet/in.h> 64 #ifdef ISO 65 #include <netiso/iso.h> 66 #endif 67 #include <nfs/nfsm_subs.h> 68 #include <nfs/rpcv2.h> 69 #include <nfs/nfsproto.h> 70 #include <nfs/nfs.h> 71 #include <nfs/nfsrvcache.h> 72 #include <nfs/nqnfs.h> 73 #include <nfs/nfs_var.h> 74 75 extern struct nfsstats nfsstats; 76 extern int nfsv2_procid[NFS_NPROCS]; 77 long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; 78 79 #define NFSRCHASH(xid) \ 80 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 81 LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 82 TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 83 u_long nfsrvhash; 84 85 #define TRUE 1 86 #define FALSE 0 87 88 #define NETFAMILY(rp) \ 89 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 90 91 /* 92 * Static array that defines which nfs rpc's are nonidempotent 93 */ 94 const int nonidempotent[NFS_NPROCS] = { 95 FALSE, 96 FALSE, 97 TRUE, 98 FALSE, 99 FALSE, 100 FALSE, 101 FALSE, 102 TRUE, 103 TRUE, 104 TRUE, 105 TRUE, 106 TRUE, 107 TRUE, 108 TRUE, 109 TRUE, 110 TRUE, 111 FALSE, 112 FALSE, 113 FALSE, 114 FALSE, 115 FALSE, 116 FALSE, 117 FALSE, 118 FALSE, 119 FALSE, 120 FALSE, 121 }; 122 123 /* True iff the rpc reply is an nfs status ONLY! */ 124 static const int nfsv2_repstat[NFS_NPROCS] = { 125 FALSE, 126 FALSE, 127 FALSE, 128 FALSE, 129 FALSE, 130 FALSE, 131 FALSE, 132 FALSE, 133 FALSE, 134 FALSE, 135 TRUE, 136 TRUE, 137 TRUE, 138 TRUE, 139 FALSE, 140 TRUE, 141 FALSE, 142 FALSE, 143 }; 144 145 /* 146 * Initialize the server request cache list 147 */ 148 void 149 nfsrv_initcache() 150 { 151 152 nfsrvhashtbl = hashinit(desirednfsrvcache, HASH_LIST, M_NFSD, 153 M_WAITOK, &nfsrvhash); 154 TAILQ_INIT(&nfsrvlruhead); 155 } 156 157 /* 158 * Look for the request in the cache 159 * If found then 160 * return action and optionally reply 161 * else 162 * insert it in the cache 163 * 164 * The rules are as follows: 165 * - if in progress, return DROP request 166 * - if completed within DELAY of the current time, return DROP it 167 * - if completed a longer time ago return REPLY if the reply was cached or 168 * return DOIT 169 * Update/add new request at end of lru list 170 */ 171 int 172 nfsrv_getcache(nd, slp, repp) 173 struct nfsrv_descript *nd; 174 struct nfssvc_sock *slp; 175 struct mbuf **repp; 176 { 177 struct nfsrvcache *rp; 178 struct mbuf *mb; 179 struct sockaddr_in *saddr; 180 caddr_t bpos; 181 int ret; 182 183 /* 184 * Don't cache recent requests for reliable transport protocols. 185 * (Maybe we should for the case of a reconnect, but..) 186 */ 187 if (!nd->nd_nam2) 188 return (RC_DOIT); 189 loop: 190 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 191 rp = rp->rc_hash.le_next) { 192 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 193 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 194 if ((rp->rc_flag & RC_LOCKED) != 0) { 195 rp->rc_flag |= RC_WANTED; 196 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 197 goto loop; 198 } 199 rp->rc_flag |= RC_LOCKED; 200 /* If not at end of LRU chain, move it there */ 201 if (rp->rc_lru.tqe_next) { 202 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 203 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 204 } 205 if (rp->rc_state == RC_UNUSED) 206 panic("nfsrv cache"); 207 if (rp->rc_state == RC_INPROG) { 208 nfsstats.srvcache_inproghits++; 209 ret = RC_DROPIT; 210 } else if (rp->rc_flag & RC_REPSTATUS) { 211 nfsstats.srvcache_nonidemdonehits++; 212 nfs_rephead(0, nd, slp, rp->rc_status, 213 0, (u_quad_t *)0, repp, &mb, &bpos); 214 ret = RC_REPLY; 215 } else if (rp->rc_flag & RC_REPMBUF) { 216 nfsstats.srvcache_nonidemdonehits++; 217 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 218 M_WAIT); 219 ret = RC_REPLY; 220 } else { 221 nfsstats.srvcache_idemdonehits++; 222 rp->rc_state = RC_INPROG; 223 ret = RC_DOIT; 224 } 225 rp->rc_flag &= ~RC_LOCKED; 226 if (rp->rc_flag & RC_WANTED) { 227 rp->rc_flag &= ~RC_WANTED; 228 wakeup((caddr_t)rp); 229 } 230 return (ret); 231 } 232 } 233 nfsstats.srvcache_misses++; 234 if (numnfsrvcache < desirednfsrvcache) { 235 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 236 M_NFSD, M_WAITOK); 237 memset((char *)rp, 0, sizeof *rp); 238 numnfsrvcache++; 239 rp->rc_flag = RC_LOCKED; 240 } else { 241 rp = nfsrvlruhead.tqh_first; 242 while ((rp->rc_flag & RC_LOCKED) != 0) { 243 rp->rc_flag |= RC_WANTED; 244 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 245 rp = nfsrvlruhead.tqh_first; 246 } 247 rp->rc_flag |= RC_LOCKED; 248 LIST_REMOVE(rp, rc_hash); 249 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 250 if (rp->rc_flag & RC_REPMBUF) 251 m_freem(rp->rc_reply); 252 if (rp->rc_flag & RC_NAM) 253 MFREE(rp->rc_nam, mb); 254 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 255 } 256 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 257 rp->rc_state = RC_INPROG; 258 rp->rc_xid = nd->nd_retxid; 259 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 260 switch (saddr->sin_family) { 261 case AF_INET: 262 rp->rc_flag |= RC_INETADDR; 263 rp->rc_inetaddr = saddr->sin_addr.s_addr; 264 break; 265 case AF_ISO: 266 default: 267 rp->rc_flag |= RC_NAM; 268 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 269 break; 270 }; 271 rp->rc_proc = nd->nd_procnum; 272 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 273 rp->rc_flag &= ~RC_LOCKED; 274 if (rp->rc_flag & RC_WANTED) { 275 rp->rc_flag &= ~RC_WANTED; 276 wakeup((caddr_t)rp); 277 } 278 return (RC_DOIT); 279 } 280 281 /* 282 * Update a request cache entry after the rpc has been done 283 */ 284 void 285 nfsrv_updatecache(nd, repvalid, repmbuf) 286 struct nfsrv_descript *nd; 287 int repvalid; 288 struct mbuf *repmbuf; 289 { 290 struct nfsrvcache *rp; 291 292 if (!nd->nd_nam2) 293 return; 294 loop: 295 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 296 rp = rp->rc_hash.le_next) { 297 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 298 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 299 if ((rp->rc_flag & RC_LOCKED) != 0) { 300 rp->rc_flag |= RC_WANTED; 301 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 302 goto loop; 303 } 304 rp->rc_flag |= RC_LOCKED; 305 rp->rc_state = RC_DONE; 306 /* 307 * If we have a valid reply update status and save 308 * the reply for non-idempotent rpc's. 309 */ 310 if (repvalid && nonidempotent[nd->nd_procnum]) { 311 if ((nd->nd_flag & ND_NFSV3) == 0 && 312 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 313 rp->rc_status = nd->nd_repstat; 314 rp->rc_flag |= RC_REPSTATUS; 315 } else { 316 rp->rc_reply = m_copym(repmbuf, 317 0, M_COPYALL, M_WAIT); 318 rp->rc_flag |= RC_REPMBUF; 319 } 320 } 321 rp->rc_flag &= ~RC_LOCKED; 322 if (rp->rc_flag & RC_WANTED) { 323 rp->rc_flag &= ~RC_WANTED; 324 wakeup((caddr_t)rp); 325 } 326 return; 327 } 328 } 329 } 330 331 /* 332 * Clean out the cache. Called when the last nfsd terminates. 333 */ 334 void 335 nfsrv_cleancache() 336 { 337 struct nfsrvcache *rp, *nextrp; 338 339 for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { 340 nextrp = rp->rc_lru.tqe_next; 341 LIST_REMOVE(rp, rc_hash); 342 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 343 free(rp, M_NFSD); 344 } 345 numnfsrvcache = 0; 346 } 347