1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)nfs_srvcache.c 8.3 (Berkeley) 3/30/95 37 * $FreeBSD: src/sys/nfs/nfs_srvcache.c,v 1.21 2000/02/13 03:32:06 peter Exp $ 38 * $DragonFly: src/sys/vfs/nfs/nfs_srvcache.c,v 1.5 2003/08/07 21:17:42 dillon Exp $ 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/malloc.h> 48 #include <sys/mount.h> 49 #include <sys/systm.h> 50 #include <sys/mbuf.h> 51 #include <sys/socket.h> 52 #include <sys/socketvar.h> /* for dup_sockaddr */ 53 54 #include <netinet/in.h> 55 #include "rpcv2.h" 56 #include "nfsproto.h" 57 #include "nfs.h" 58 #include "nfsrvcache.h" 59 60 #ifndef NFS_NOSERVER 61 extern struct nfsstats nfsstats; 62 extern int nfsv2_procid[NFS_NPROCS]; 63 static long numnfsrvcache; 64 static long desirednfsrvcache = NFSRVCACHESIZ; 65 66 #define NFSRCHASH(xid) \ 67 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 68 static LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 69 static TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 70 static u_long nfsrvhash; 71 72 #define TRUE 1 73 #define FALSE 0 74 75 #define NETFAMILY(rp) \ 76 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 77 78 /* 79 * Static array that defines which nfs rpc's are nonidempotent 80 */ 81 static int nonidempotent[NFS_NPROCS] = { 82 FALSE, 83 FALSE, 84 TRUE, 85 FALSE, 86 FALSE, 87 FALSE, 88 FALSE, 89 TRUE, 90 TRUE, 91 TRUE, 92 TRUE, 93 TRUE, 94 TRUE, 95 TRUE, 96 TRUE, 97 TRUE, 98 FALSE, 99 FALSE, 100 FALSE, 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 nfsv2_repstat[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 }; 131 132 /* 133 * Initialize the server request cache list 134 */ 135 void 136 nfsrv_initcache() 137 { 138 139 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash); 140 TAILQ_INIT(&nfsrvlruhead); 141 } 142 143 /* 144 * Look for the request in the cache 145 * If found then 146 * return action and optionally reply 147 * else 148 * insert it in the cache 149 * 150 * The rules are as follows: 151 * - if in progress, return DROP request 152 * - if completed within DELAY of the current time, return DROP it 153 * - if completed a longer time ago return REPLY if the reply was cached or 154 * return DOIT 155 * Update/add new request at end of lru list 156 */ 157 int 158 nfsrv_getcache(nd, slp, repp) 159 struct nfsrv_descript *nd; 160 struct nfssvc_sock *slp; 161 struct mbuf **repp; 162 { 163 struct nfsrvcache *rp; 164 struct mbuf *mb; 165 struct sockaddr_in *saddr; 166 caddr_t bpos; 167 int ret; 168 169 /* 170 * Don't cache recent requests for reliable transport protocols. 171 * (Maybe we should for the case of a reconnect, but..) 172 */ 173 if (!nd->nd_nam2) 174 return (RC_DOIT); 175 loop: 176 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 177 rp = rp->rc_hash.le_next) { 178 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 179 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 180 NFS_DPF(RC, ("H%03x", rp->rc_xid & 0xfff)); 181 if ((rp->rc_flag & RC_LOCKED) != 0) { 182 rp->rc_flag |= RC_WANTED; 183 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 184 goto loop; 185 } 186 rp->rc_flag |= RC_LOCKED; 187 /* If not at end of LRU chain, move it there */ 188 if (rp->rc_lru.tqe_next) { 189 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 190 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 191 } 192 if (rp->rc_state == RC_UNUSED) 193 panic("nfsrv cache"); 194 if (rp->rc_state == RC_INPROG) { 195 nfsstats.srvcache_inproghits++; 196 ret = RC_DROPIT; 197 } else if (rp->rc_flag & RC_REPSTATUS) { 198 nfsstats.srvcache_nonidemdonehits++; 199 nfs_rephead(0, nd, slp, rp->rc_status, 200 0, (u_quad_t *)0, repp, &mb, &bpos); 201 ret = RC_REPLY; 202 } else if (rp->rc_flag & RC_REPMBUF) { 203 nfsstats.srvcache_nonidemdonehits++; 204 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 205 M_WAIT); 206 ret = RC_REPLY; 207 } else { 208 nfsstats.srvcache_idemdonehits++; 209 rp->rc_state = RC_INPROG; 210 ret = RC_DOIT; 211 } 212 rp->rc_flag &= ~RC_LOCKED; 213 if (rp->rc_flag & RC_WANTED) { 214 rp->rc_flag &= ~RC_WANTED; 215 wakeup((caddr_t)rp); 216 } 217 return (ret); 218 } 219 } 220 nfsstats.srvcache_misses++; 221 NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff)); 222 if (numnfsrvcache < desirednfsrvcache) { 223 rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, 224 M_NFSD, M_WAITOK); 225 bzero((char *)rp, sizeof *rp); 226 numnfsrvcache++; 227 rp->rc_flag = RC_LOCKED; 228 } else { 229 rp = nfsrvlruhead.tqh_first; 230 while ((rp->rc_flag & RC_LOCKED) != 0) { 231 rp->rc_flag |= RC_WANTED; 232 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 233 rp = nfsrvlruhead.tqh_first; 234 } 235 rp->rc_flag |= RC_LOCKED; 236 LIST_REMOVE(rp, rc_hash); 237 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 238 if (rp->rc_flag & RC_REPMBUF) 239 m_freem(rp->rc_reply); 240 if (rp->rc_flag & RC_NAM) 241 FREE(rp->rc_nam, M_SONAME); 242 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 243 } 244 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 245 rp->rc_state = RC_INPROG; 246 rp->rc_xid = nd->nd_retxid; 247 saddr = (struct sockaddr_in *)nd->nd_nam; 248 switch (saddr->sin_family) { 249 case AF_INET: 250 rp->rc_flag |= RC_INETADDR; 251 rp->rc_inetaddr = saddr->sin_addr.s_addr; 252 break; 253 case AF_ISO: 254 default: 255 rp->rc_flag |= RC_NAM; 256 rp->rc_nam = dup_sockaddr(nd->nd_nam, 1); 257 break; 258 }; 259 rp->rc_proc = nd->nd_procnum; 260 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 261 rp->rc_flag &= ~RC_LOCKED; 262 if (rp->rc_flag & RC_WANTED) { 263 rp->rc_flag &= ~RC_WANTED; 264 wakeup((caddr_t)rp); 265 } 266 return (RC_DOIT); 267 } 268 269 /* 270 * Update a request cache entry after the rpc has been done 271 */ 272 void 273 nfsrv_updatecache(nd, repvalid, repmbuf) 274 struct nfsrv_descript *nd; 275 int repvalid; 276 struct mbuf *repmbuf; 277 { 278 struct nfsrvcache *rp; 279 280 if (!nd->nd_nam2) 281 return; 282 loop: 283 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 284 rp = rp->rc_hash.le_next) { 285 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 286 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 287 NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff)); 288 if ((rp->rc_flag & RC_LOCKED) != 0) { 289 rp->rc_flag |= RC_WANTED; 290 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 291 goto loop; 292 } 293 rp->rc_flag |= RC_LOCKED; 294 if (rp->rc_state == RC_DONE) { 295 /* 296 * This can occur if the cache is too small. 297 * Retransmits of the same request aren't 298 * dropped so we may see the operation 299 * complete more then once. 300 */ 301 if (rp->rc_flag & RC_REPMBUF) { 302 m_freem(rp->rc_reply); 303 rp->rc_flag &= ~RC_REPMBUF; 304 } 305 } 306 rp->rc_state = RC_DONE; 307 /* 308 * If we have a valid reply update status and save 309 * the reply for non-idempotent rpc's. 310 */ 311 if (repvalid && nonidempotent[nd->nd_procnum]) { 312 if ((nd->nd_flag & ND_NFSV3) == 0 && 313 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 314 rp->rc_status = nd->nd_repstat; 315 rp->rc_flag |= RC_REPSTATUS; 316 } else { 317 rp->rc_reply = m_copym(repmbuf, 318 0, M_COPYALL, M_WAIT); 319 rp->rc_flag |= RC_REPMBUF; 320 } 321 } 322 rp->rc_flag &= ~RC_LOCKED; 323 if (rp->rc_flag & RC_WANTED) { 324 rp->rc_flag &= ~RC_WANTED; 325 wakeup((caddr_t)rp); 326 } 327 return; 328 } 329 } 330 NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff)); 331 } 332 333 /* 334 * Clean out the cache. Called when the last nfsd terminates. 335 */ 336 void 337 nfsrv_cleancache() 338 { 339 struct nfsrvcache *rp, *nextrp; 340 341 for (rp = nfsrvlruhead.tqh_first; rp != 0; rp = nextrp) { 342 nextrp = rp->rc_lru.tqe_next; 343 LIST_REMOVE(rp, rc_hash); 344 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 345 if (rp->rc_flag & RC_REPMBUF) 346 m_freem(rp->rc_reply); 347 if (rp->rc_flag & RC_NAM) 348 free(rp->rc_nam, M_SONAME); 349 free(rp, M_NFSD); 350 } 351 numnfsrvcache = 0; 352 } 353 354 #endif /* NFS_NOSERVER */ 355