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 1.13 2008/01/05 14:02:41 swildner 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 static long numnfsrvcache; 62 static long desirednfsrvcache = NFSRVCACHESIZ; 63 64 #define NFSRCHASH(xid) \ 65 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 66 static LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 67 static TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 68 static u_long nfsrvhash; 69 70 #define TRUE 1 71 #define FALSE 0 72 73 #define NETFAMILY(rp) \ 74 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 75 76 /* 77 * Static array that defines which nfs rpc's are nonidempotent 78 */ 79 static int nonidempotent[NFS_NPROCS] = { 80 FALSE, 81 FALSE, 82 TRUE, 83 FALSE, 84 FALSE, 85 FALSE, 86 FALSE, 87 TRUE, 88 TRUE, 89 TRUE, 90 TRUE, 91 TRUE, 92 TRUE, 93 TRUE, 94 TRUE, 95 TRUE, 96 FALSE, 97 FALSE, 98 FALSE, 99 FALSE, 100 FALSE, 101 FALSE, 102 FALSE, 103 FALSE, 104 FALSE, 105 FALSE, 106 }; 107 108 /* True iff the rpc reply is an nfs status ONLY! */ 109 static int nfsv2_repstat[NFS_NPROCS] = { 110 FALSE, 111 FALSE, 112 FALSE, 113 FALSE, 114 FALSE, 115 FALSE, 116 FALSE, 117 FALSE, 118 FALSE, 119 FALSE, 120 TRUE, 121 TRUE, 122 TRUE, 123 TRUE, 124 FALSE, 125 TRUE, 126 FALSE, 127 FALSE, 128 }; 129 130 /* 131 * Initialize the server request cache list 132 */ 133 void 134 nfsrv_initcache(void) 135 { 136 137 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash); 138 TAILQ_INIT(&nfsrvlruhead); 139 } 140 141 /* 142 * Look for the request in the cache 143 * If found then 144 * return action and optionally reply 145 * else 146 * insert it in the cache 147 * 148 * The rules are as follows: 149 * - if in progress, return DROP request 150 * - if completed within DELAY of the current time, return DROP it 151 * - if completed a longer time ago return REPLY if the reply was cached or 152 * return DOIT 153 * Update/add new request at end of lru list 154 */ 155 int 156 nfsrv_getcache(struct nfsrv_descript *nd, struct nfssvc_sock *slp, 157 struct mbuf **repp) 158 { 159 struct nfsrvcache *rp; 160 struct mbuf *mb; 161 struct sockaddr_in *saddr; 162 caddr_t bpos; 163 int ret; 164 165 /* 166 * Don't cache recent requests for reliable transport protocols. 167 * (Maybe we should for the case of a reconnect, but..) 168 */ 169 if (!nd->nd_nam2) 170 return (RC_DOIT); 171 loop: 172 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 173 rp = rp->rc_hash.le_next) { 174 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 175 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 176 NFS_DPF(RC, ("H%03x", rp->rc_xid & 0xfff)); 177 if ((rp->rc_flag & RC_LOCKED) != 0) { 178 rp->rc_flag |= RC_WANTED; 179 tsleep((caddr_t)rp, 0, "nfsrc", 0); 180 goto loop; 181 } 182 rp->rc_flag |= RC_LOCKED; 183 /* If not at end of LRU chain, move it there */ 184 if (TAILQ_NEXT(rp, rc_lru) != NULL) { 185 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 186 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 187 } 188 if (rp->rc_state == RC_UNUSED) 189 panic("nfsrv cache"); 190 if (rp->rc_state == RC_INPROG) { 191 nfsstats.srvcache_inproghits++; 192 ret = RC_DROPIT; 193 } else if (rp->rc_flag & RC_REPSTATUS) { 194 nfsstats.srvcache_nonidemdonehits++; 195 nfs_rephead(0, nd, slp, rp->rc_status, 196 repp, &mb, &bpos); 197 ret = RC_REPLY; 198 } else if (rp->rc_flag & RC_REPMBUF) { 199 nfsstats.srvcache_nonidemdonehits++; 200 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 201 MB_WAIT); 202 ret = RC_REPLY; 203 } else { 204 nfsstats.srvcache_idemdonehits++; 205 rp->rc_state = RC_INPROG; 206 ret = RC_DOIT; 207 } 208 rp->rc_flag &= ~RC_LOCKED; 209 if (rp->rc_flag & RC_WANTED) { 210 rp->rc_flag &= ~RC_WANTED; 211 wakeup((caddr_t)rp); 212 } 213 return (ret); 214 } 215 } 216 nfsstats.srvcache_misses++; 217 NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff)); 218 if (numnfsrvcache < desirednfsrvcache) { 219 rp = kmalloc((u_long)sizeof *rp, M_NFSD, M_WAITOK | M_ZERO); 220 numnfsrvcache++; 221 rp->rc_flag = RC_LOCKED; 222 } else { 223 rp = TAILQ_FIRST(&nfsrvlruhead); 224 while ((rp->rc_flag & RC_LOCKED) != 0) { 225 rp->rc_flag |= RC_WANTED; 226 tsleep((caddr_t)rp, 0, "nfsrc", 0); 227 rp = TAILQ_FIRST(&nfsrvlruhead); 228 } 229 rp->rc_flag |= RC_LOCKED; 230 LIST_REMOVE(rp, rc_hash); 231 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 232 if (rp->rc_flag & RC_REPMBUF) { 233 m_freem(rp->rc_reply); 234 rp->rc_reply = NULL; 235 rp->rc_flag &= ~RC_REPMBUF; 236 } 237 if (rp->rc_flag & RC_NAM) { 238 FREE(rp->rc_nam, M_SONAME); 239 rp->rc_nam = NULL; 240 rp->rc_flag &= ~RC_NAM; 241 } 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); 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(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf) 274 { 275 struct nfsrvcache *rp; 276 277 if (!nd->nd_nam2) 278 return; 279 loop: 280 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 281 rp = rp->rc_hash.le_next) { 282 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 283 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 284 NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff)); 285 if ((rp->rc_flag & RC_LOCKED) != 0) { 286 rp->rc_flag |= RC_WANTED; 287 tsleep((caddr_t)rp, 0, "nfsrc", 0); 288 goto loop; 289 } 290 rp->rc_flag |= RC_LOCKED; 291 if (rp->rc_state == RC_DONE) { 292 /* 293 * This can occur if the cache is too small. 294 * Retransmits of the same request aren't 295 * dropped so we may see the operation 296 * complete more then once. 297 */ 298 if (rp->rc_flag & RC_REPMBUF) { 299 m_freem(rp->rc_reply); 300 rp->rc_reply = NULL; 301 rp->rc_flag &= ~RC_REPMBUF; 302 } 303 } 304 rp->rc_state = RC_DONE; 305 306 /* 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 if (rp->rc_flag & RC_REPMBUF) { 317 m_freem(rp->rc_reply); 318 rp->rc_reply = NULL; 319 rp->rc_flag &= ~RC_REPMBUF; 320 } 321 rp->rc_reply = m_copym(repmbuf, 0, 322 M_COPYALL, MB_WAIT); 323 rp->rc_flag |= RC_REPMBUF; 324 } 325 } 326 rp->rc_flag &= ~RC_LOCKED; 327 if (rp->rc_flag & RC_WANTED) { 328 rp->rc_flag &= ~RC_WANTED; 329 wakeup((caddr_t)rp); 330 } 331 return; 332 } 333 } 334 NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff)); 335 } 336 337 /* 338 * Clean out the cache. Called when the last nfsd terminates. 339 */ 340 void 341 nfsrv_cleancache(void) 342 { 343 struct nfsrvcache *rp; 344 345 while ((rp = TAILQ_FIRST(&nfsrvlruhead)) != NULL) { 346 if (rp->rc_flag & RC_LOCKED) { 347 rp->rc_flag |= RC_WANTED; 348 tsleep((caddr_t)rp, 0, "nfsrc", 0); 349 continue; 350 } 351 LIST_REMOVE(rp, rc_hash); 352 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 353 if (rp->rc_flag & RC_REPMBUF) { 354 m_freem(rp->rc_reply); 355 rp->rc_reply = NULL; 356 rp->rc_flag &= ~RC_REPMBUF; 357 } 358 if (rp->rc_flag & RC_NAM) { 359 kfree(rp->rc_nam, M_SONAME); 360 rp->rc_nam = NULL; 361 rp->rc_flag &= ~RC_NAM; 362 } 363 kfree(rp, M_NFSD); 364 } 365 numnfsrvcache = 0; 366 } 367 368 #endif /* NFS_NOSERVER */ 369