1 /* $NetBSD: nfs_srvcache.c,v 1.22 2003/04/02 15:14:22 yamt 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 1.22 2003/04/02 15:14:22 yamt 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 const 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 LIST_FOREACH(rp, NFSRCHASH(nd->nd_retxid), rc_hash) { 191 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 192 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 193 if ((rp->rc_flag & RC_LOCKED) != 0) { 194 rp->rc_flag |= RC_WANTED; 195 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 196 goto loop; 197 } 198 rp->rc_flag |= RC_LOCKED; 199 /* If not at end of LRU chain, move it there */ 200 if (TAILQ_NEXT(rp, rc_lru)) { 201 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 202 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 203 } 204 if (rp->rc_state == RC_UNUSED) 205 panic("nfsrv cache"); 206 if (rp->rc_state == RC_INPROG) { 207 nfsstats.srvcache_inproghits++; 208 ret = RC_DROPIT; 209 } else if (rp->rc_flag & RC_REPSTATUS) { 210 nfsstats.srvcache_nonidemdonehits++; 211 nfs_rephead(0, nd, slp, rp->rc_status, 212 0, (u_quad_t *)0, repp, &mb, &bpos); 213 ret = RC_REPLY; 214 } else if (rp->rc_flag & RC_REPMBUF) { 215 nfsstats.srvcache_nonidemdonehits++; 216 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 217 M_WAIT); 218 ret = RC_REPLY; 219 } else { 220 nfsstats.srvcache_idemdonehits++; 221 rp->rc_state = RC_INPROG; 222 ret = RC_DOIT; 223 } 224 rp->rc_flag &= ~RC_LOCKED; 225 if (rp->rc_flag & RC_WANTED) { 226 rp->rc_flag &= ~RC_WANTED; 227 wakeup((caddr_t)rp); 228 } 229 return (ret); 230 } 231 } 232 nfsstats.srvcache_misses++; 233 if (numnfsrvcache < desirednfsrvcache) { 234 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 235 M_NFSD, M_WAITOK); 236 memset((char *)rp, 0, sizeof *rp); 237 numnfsrvcache++; 238 rp->rc_flag = RC_LOCKED; 239 } else { 240 rp = TAILQ_FIRST(&nfsrvlruhead); 241 while ((rp->rc_flag & RC_LOCKED) != 0) { 242 rp->rc_flag |= RC_WANTED; 243 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 244 rp = TAILQ_FIRST(&nfsrvlruhead); 245 } 246 rp->rc_flag |= RC_LOCKED; 247 LIST_REMOVE(rp, rc_hash); 248 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 249 if (rp->rc_flag & RC_REPMBUF) 250 m_freem(rp->rc_reply); 251 if (rp->rc_flag & RC_NAM) 252 (void) m_free(rp->rc_nam); 253 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 254 } 255 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 256 rp->rc_state = RC_INPROG; 257 rp->rc_xid = nd->nd_retxid; 258 saddr = mtod(nd->nd_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(nd->nd_nam, 0, M_COPYALL, M_WAIT); 268 break; 269 }; 270 rp->rc_proc = nd->nd_procnum; 271 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 272 rp->rc_flag &= ~RC_LOCKED; 273 if (rp->rc_flag & RC_WANTED) { 274 rp->rc_flag &= ~RC_WANTED; 275 wakeup((caddr_t)rp); 276 } 277 return (RC_DOIT); 278 } 279 280 /* 281 * Update a request cache entry after the rpc has been done 282 */ 283 void 284 nfsrv_updatecache(nd, repvalid, repmbuf) 285 struct nfsrv_descript *nd; 286 int repvalid; 287 struct mbuf *repmbuf; 288 { 289 struct nfsrvcache *rp; 290 291 if (!nd->nd_nam2) 292 return; 293 loop: 294 LIST_FOREACH(rp, NFSRCHASH(nd->nd_retxid), rc_hash) { 295 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 296 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 297 if ((rp->rc_flag & RC_LOCKED) != 0) { 298 rp->rc_flag |= RC_WANTED; 299 (void) tsleep((caddr_t)rp, PZERO-1, "nfsrc", 0); 300 goto loop; 301 } 302 rp->rc_flag |= RC_LOCKED; 303 rp->rc_state = RC_DONE; 304 /* 305 * If we have a valid reply update status and save 306 * the reply for non-idempotent rpc's. 307 */ 308 if (repvalid && nonidempotent[nd->nd_procnum]) { 309 if ((nd->nd_flag & ND_NFSV3) == 0 && 310 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 311 rp->rc_status = nd->nd_repstat; 312 rp->rc_flag |= RC_REPSTATUS; 313 } else { 314 rp->rc_reply = m_copym(repmbuf, 315 0, M_COPYALL, M_WAIT); 316 rp->rc_flag |= RC_REPMBUF; 317 } 318 } 319 rp->rc_flag &= ~RC_LOCKED; 320 if (rp->rc_flag & RC_WANTED) { 321 rp->rc_flag &= ~RC_WANTED; 322 wakeup((caddr_t)rp); 323 } 324 return; 325 } 326 } 327 } 328 329 /* 330 * Clean out the cache. Called when the last nfsd terminates. 331 */ 332 void 333 nfsrv_cleancache() 334 { 335 struct nfsrvcache *rp, *nextrp; 336 337 for (rp = TAILQ_FIRST(&nfsrvlruhead); rp != 0; rp = nextrp) { 338 nextrp = TAILQ_NEXT(rp, rc_lru); 339 LIST_REMOVE(rp, rc_hash); 340 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 341 free(rp, M_NFSD); 342 } 343 numnfsrvcache = 0; 344 } 345