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 1.12 2006/09/05 03:48:13 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(void) 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(struct nfsrv_descript *nd, struct nfssvc_sock *slp, 159 struct mbuf **repp) 160 { 161 struct nfsrvcache *rp; 162 struct mbuf *mb; 163 struct sockaddr_in *saddr; 164 caddr_t bpos; 165 int ret; 166 167 /* 168 * Don't cache recent requests for reliable transport protocols. 169 * (Maybe we should for the case of a reconnect, but..) 170 */ 171 if (!nd->nd_nam2) 172 return (RC_DOIT); 173 loop: 174 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 175 rp = rp->rc_hash.le_next) { 176 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 177 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 178 NFS_DPF(RC, ("H%03x", rp->rc_xid & 0xfff)); 179 if ((rp->rc_flag & RC_LOCKED) != 0) { 180 rp->rc_flag |= RC_WANTED; 181 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 182 goto loop; 183 } 184 rp->rc_flag |= RC_LOCKED; 185 /* If not at end of LRU chain, move it there */ 186 if (TAILQ_NEXT(rp, rc_lru) != NULL) { 187 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 188 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 189 } 190 if (rp->rc_state == RC_UNUSED) 191 panic("nfsrv cache"); 192 if (rp->rc_state == RC_INPROG) { 193 nfsstats.srvcache_inproghits++; 194 ret = RC_DROPIT; 195 } else if (rp->rc_flag & RC_REPSTATUS) { 196 nfsstats.srvcache_nonidemdonehits++; 197 nfs_rephead(0, nd, slp, rp->rc_status, 198 repp, &mb, &bpos); 199 ret = RC_REPLY; 200 } else if (rp->rc_flag & RC_REPMBUF) { 201 nfsstats.srvcache_nonidemdonehits++; 202 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 203 MB_WAIT); 204 ret = RC_REPLY; 205 } else { 206 nfsstats.srvcache_idemdonehits++; 207 rp->rc_state = RC_INPROG; 208 ret = RC_DOIT; 209 } 210 rp->rc_flag &= ~RC_LOCKED; 211 if (rp->rc_flag & RC_WANTED) { 212 rp->rc_flag &= ~RC_WANTED; 213 wakeup((caddr_t)rp); 214 } 215 return (ret); 216 } 217 } 218 nfsstats.srvcache_misses++; 219 NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff)); 220 if (numnfsrvcache < desirednfsrvcache) { 221 rp = (struct nfsrvcache *)kmalloc((u_long)sizeof *rp, 222 M_NFSD, M_WAITOK); 223 bzero((char *)rp, sizeof *rp); 224 numnfsrvcache++; 225 rp->rc_flag = RC_LOCKED; 226 } else { 227 rp = TAILQ_FIRST(&nfsrvlruhead); 228 while ((rp->rc_flag & RC_LOCKED) != 0) { 229 rp->rc_flag |= RC_WANTED; 230 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 231 rp = TAILQ_FIRST(&nfsrvlruhead); 232 } 233 rp->rc_flag |= RC_LOCKED; 234 LIST_REMOVE(rp, rc_hash); 235 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 236 if (rp->rc_flag & RC_REPMBUF) 237 m_freem(rp->rc_reply); 238 if (rp->rc_flag & RC_NAM) 239 FREE(rp->rc_nam, M_SONAME); 240 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 241 } 242 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 243 rp->rc_state = RC_INPROG; 244 rp->rc_xid = nd->nd_retxid; 245 saddr = (struct sockaddr_in *)nd->nd_nam; 246 switch (saddr->sin_family) { 247 case AF_INET: 248 rp->rc_flag |= RC_INETADDR; 249 rp->rc_inetaddr = saddr->sin_addr.s_addr; 250 break; 251 case AF_ISO: 252 default: 253 rp->rc_flag |= RC_NAM; 254 rp->rc_nam = dup_sockaddr(nd->nd_nam); 255 break; 256 }; 257 rp->rc_proc = nd->nd_procnum; 258 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 259 rp->rc_flag &= ~RC_LOCKED; 260 if (rp->rc_flag & RC_WANTED) { 261 rp->rc_flag &= ~RC_WANTED; 262 wakeup((caddr_t)rp); 263 } 264 return (RC_DOIT); 265 } 266 267 /* 268 * Update a request cache entry after the rpc has been done 269 */ 270 void 271 nfsrv_updatecache(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf) 272 { 273 struct nfsrvcache *rp; 274 275 if (!nd->nd_nam2) 276 return; 277 loop: 278 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 279 rp = rp->rc_hash.le_next) { 280 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 281 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 282 NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff)); 283 if ((rp->rc_flag & RC_LOCKED) != 0) { 284 rp->rc_flag |= RC_WANTED; 285 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 286 goto loop; 287 } 288 rp->rc_flag |= RC_LOCKED; 289 if (rp->rc_state == RC_DONE) { 290 /* 291 * This can occur if the cache is too small. 292 * Retransmits of the same request aren't 293 * dropped so we may see the operation 294 * complete more then once. 295 */ 296 if (rp->rc_flag & RC_REPMBUF) { 297 m_freem(rp->rc_reply); 298 rp->rc_flag &= ~RC_REPMBUF; 299 } 300 } 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, MB_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 NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff)); 326 } 327 328 /* 329 * Clean out the cache. Called when the last nfsd terminates. 330 */ 331 void 332 nfsrv_cleancache(void) 333 { 334 struct nfsrvcache *rp, *nextrp; 335 336 TAILQ_FOREACH_MUTABLE(rp, &nfsrvlruhead, rc_lru, nextrp) { 337 LIST_REMOVE(rp, rc_hash); 338 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 339 if (rp->rc_flag & RC_REPMBUF) 340 m_freem(rp->rc_reply); 341 if (rp->rc_flag & RC_NAM) 342 kfree(rp->rc_nam, M_SONAME); 343 kfree(rp, M_NFSD); 344 } 345 numnfsrvcache = 0; 346 } 347 348 #endif /* NFS_NOSERVER */ 349