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 */ 39 40 /* 41 * Reference: Chet Juszczak, "Improving the Performance and Correctness 42 * of an NFS Server", in Proc. Winter 1989 USENIX Conference, 43 * pages 53-63. San Diego, February 1989. 44 */ 45 #include <sys/param.h> 46 #include <sys/malloc.h> 47 #include <sys/mount.h> 48 #include <sys/systm.h> 49 #include <sys/mbuf.h> 50 #include <sys/socket.h> 51 #include <sys/socketvar.h> /* for dup_sockaddr */ 52 53 #include <netinet/in.h> 54 #include "rpcv2.h" 55 #include "nfsproto.h" 56 #include "nfs.h" 57 #include "nfsrvcache.h" 58 59 #ifndef NFS_NOSERVER 60 static long numnfsrvcache; 61 static long desirednfsrvcache = NFSRVCACHESIZ; 62 63 #define NFSRCHASH(xid) \ 64 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 65 static LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 66 static TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 67 static u_long nfsrvhash; 68 69 #define TRUE 1 70 #define FALSE 0 71 72 #define NETFAMILY(rp) \ 73 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 74 75 struct lwkt_token srvcache_token = LWKT_TOKEN_INITIALIZER(srvcache_token); 76 77 /* 78 * Static array that defines which nfs rpc's are nonidempotent 79 */ 80 static int nonidempotent[NFS_NPROCS] = { 81 FALSE, 82 FALSE, 83 TRUE, 84 FALSE, 85 FALSE, 86 FALSE, 87 FALSE, 88 TRUE, 89 TRUE, 90 TRUE, 91 TRUE, 92 TRUE, 93 TRUE, 94 TRUE, 95 TRUE, 96 TRUE, 97 FALSE, 98 FALSE, 99 FALSE, 100 FALSE, 101 FALSE, 102 FALSE, 103 FALSE, 104 FALSE, 105 FALSE, 106 FALSE, 107 }; 108 109 /* True iff the rpc reply is an nfs status ONLY! */ 110 static int nfsv2_repstat[NFS_NPROCS] = { 111 FALSE, 112 FALSE, 113 FALSE, 114 FALSE, 115 FALSE, 116 FALSE, 117 FALSE, 118 FALSE, 119 FALSE, 120 FALSE, 121 TRUE, 122 TRUE, 123 TRUE, 124 TRUE, 125 FALSE, 126 TRUE, 127 FALSE, 128 FALSE, 129 }; 130 131 /* 132 * Initialize the server request cache list 133 */ 134 void 135 nfsrv_initcache(void) 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); 171 172 lwkt_gettoken(&srvcache_token); 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 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 lwkt_reltoken(&srvcache_token); 216 return (ret); 217 } 218 } 219 220 nfsstats.srvcache_misses++; 221 NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff)); 222 if (numnfsrvcache < desirednfsrvcache) { 223 rp = kmalloc((u_long)sizeof *rp, M_NFSD, M_WAITOK | M_ZERO); 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 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 rp->rc_reply = NULL; 239 rp->rc_flag &= ~RC_REPMBUF; 240 } 241 if (rp->rc_flag & RC_NAM) { 242 kfree(rp->rc_nam, M_SONAME); 243 rp->rc_nam = NULL; 244 rp->rc_flag &= ~RC_NAM; 245 } 246 } 247 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 248 249 rp->rc_state = RC_INPROG; 250 rp->rc_xid = nd->nd_retxid; 251 saddr = (struct sockaddr_in *)nd->nd_nam; 252 switch (saddr->sin_family) { 253 case AF_INET: 254 rp->rc_flag |= RC_INETADDR; 255 rp->rc_inetaddr = saddr->sin_addr.s_addr; 256 break; 257 case AF_ISO: 258 default: 259 rp->rc_flag |= RC_NAM; 260 rp->rc_nam = dup_sockaddr(nd->nd_nam); 261 break; 262 }; 263 rp->rc_proc = nd->nd_procnum; 264 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 265 rp->rc_flag &= ~RC_LOCKED; 266 if (rp->rc_flag & RC_WANTED) { 267 rp->rc_flag &= ~RC_WANTED; 268 wakeup((caddr_t)rp); 269 } 270 lwkt_reltoken(&srvcache_token); 271 272 return (RC_DOIT); 273 } 274 275 /* 276 * Update a request cache entry after the rpc has been done 277 */ 278 void 279 nfsrv_updatecache(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf) 280 { 281 struct nfsrvcache *rp; 282 283 if (!nd->nd_nam2) 284 return; 285 286 lwkt_gettoken(&srvcache_token); 287 loop: 288 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 289 rp = rp->rc_hash.le_next) { 290 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 291 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 292 NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff)); 293 if ((rp->rc_flag & RC_LOCKED) != 0) { 294 rp->rc_flag |= RC_WANTED; 295 tsleep((caddr_t)rp, 0, "nfsrc", 0); 296 goto loop; 297 } 298 rp->rc_flag |= RC_LOCKED; 299 if (rp->rc_state == RC_DONE) { 300 /* 301 * This can occur if the cache is too small. 302 * Retransmits of the same request aren't 303 * dropped so we may see the operation 304 * complete more then once. 305 */ 306 if (rp->rc_flag & RC_REPMBUF) { 307 m_freem(rp->rc_reply); 308 rp->rc_reply = NULL; 309 rp->rc_flag &= ~RC_REPMBUF; 310 } 311 } 312 rp->rc_state = RC_DONE; 313 314 /* 315 * If we have a valid reply update status and save 316 * the reply for non-idempotent rpc's. 317 */ 318 if (repvalid && nonidempotent[nd->nd_procnum]) { 319 if ((nd->nd_flag & ND_NFSV3) == 0 && 320 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 321 rp->rc_status = nd->nd_repstat; 322 rp->rc_flag |= RC_REPSTATUS; 323 } else { 324 if (rp->rc_flag & RC_REPMBUF) { 325 m_freem(rp->rc_reply); 326 rp->rc_reply = NULL; 327 rp->rc_flag &= ~RC_REPMBUF; 328 } 329 rp->rc_reply = m_copym(repmbuf, 0, 330 M_COPYALL, MB_WAIT); 331 rp->rc_flag |= RC_REPMBUF; 332 } 333 } 334 rp->rc_flag &= ~RC_LOCKED; 335 if (rp->rc_flag & RC_WANTED) { 336 rp->rc_flag &= ~RC_WANTED; 337 wakeup((caddr_t)rp); 338 } 339 break; 340 } 341 } 342 lwkt_reltoken(&srvcache_token); 343 NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff)); 344 } 345 346 /* 347 * Clean out the cache. Called when the last nfsd terminates. 348 */ 349 void 350 nfsrv_cleancache(void) 351 { 352 struct nfsrvcache *rp; 353 354 lwkt_gettoken(&srvcache_token); 355 while ((rp = TAILQ_FIRST(&nfsrvlruhead)) != NULL) { 356 if (rp->rc_flag & RC_LOCKED) { 357 rp->rc_flag |= RC_WANTED; 358 tsleep((caddr_t)rp, 0, "nfsrc", 0); 359 continue; 360 } 361 LIST_REMOVE(rp, rc_hash); 362 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 363 if (rp->rc_flag & RC_REPMBUF) { 364 m_freem(rp->rc_reply); 365 rp->rc_reply = NULL; 366 rp->rc_flag &= ~RC_REPMBUF; 367 } 368 if (rp->rc_flag & RC_NAM) { 369 kfree(rp->rc_nam, M_SONAME); 370 rp->rc_nam = NULL; 371 rp->rc_flag &= ~RC_NAM; 372 } 373 kfree(rp, M_NFSD); 374 } 375 numnfsrvcache = 0; 376 lwkt_reltoken(&srvcache_token); 377 } 378 379 #endif /* NFS_NOSERVER */ 380