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 (void) 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 = (struct nfsrvcache *)kmalloc((u_long)sizeof *rp, 220 M_NFSD, M_WAITOK | M_ZERO); 221 numnfsrvcache++; 222 rp->rc_flag = RC_LOCKED; 223 } else { 224 rp = TAILQ_FIRST(&nfsrvlruhead); 225 while ((rp->rc_flag & RC_LOCKED) != 0) { 226 rp->rc_flag |= RC_WANTED; 227 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 228 rp = TAILQ_FIRST(&nfsrvlruhead); 229 } 230 rp->rc_flag |= RC_LOCKED; 231 LIST_REMOVE(rp, rc_hash); 232 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 233 if (rp->rc_flag & RC_REPMBUF) 234 m_freem(rp->rc_reply); 235 if (rp->rc_flag & RC_NAM) 236 FREE(rp->rc_nam, M_SONAME); 237 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 238 } 239 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 240 rp->rc_state = RC_INPROG; 241 rp->rc_xid = nd->nd_retxid; 242 saddr = (struct sockaddr_in *)nd->nd_nam; 243 switch (saddr->sin_family) { 244 case AF_INET: 245 rp->rc_flag |= RC_INETADDR; 246 rp->rc_inetaddr = saddr->sin_addr.s_addr; 247 break; 248 case AF_ISO: 249 default: 250 rp->rc_flag |= RC_NAM; 251 rp->rc_nam = dup_sockaddr(nd->nd_nam); 252 break; 253 }; 254 rp->rc_proc = nd->nd_procnum; 255 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 256 rp->rc_flag &= ~RC_LOCKED; 257 if (rp->rc_flag & RC_WANTED) { 258 rp->rc_flag &= ~RC_WANTED; 259 wakeup((caddr_t)rp); 260 } 261 return (RC_DOIT); 262 } 263 264 /* 265 * Update a request cache entry after the rpc has been done 266 */ 267 void 268 nfsrv_updatecache(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf) 269 { 270 struct nfsrvcache *rp; 271 272 if (!nd->nd_nam2) 273 return; 274 loop: 275 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; 276 rp = rp->rc_hash.le_next) { 277 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && 278 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 279 NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff)); 280 if ((rp->rc_flag & RC_LOCKED) != 0) { 281 rp->rc_flag |= RC_WANTED; 282 (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); 283 goto loop; 284 } 285 rp->rc_flag |= RC_LOCKED; 286 if (rp->rc_state == RC_DONE) { 287 /* 288 * This can occur if the cache is too small. 289 * Retransmits of the same request aren't 290 * dropped so we may see the operation 291 * complete more then once. 292 */ 293 if (rp->rc_flag & RC_REPMBUF) { 294 m_freem(rp->rc_reply); 295 rp->rc_flag &= ~RC_REPMBUF; 296 } 297 } 298 rp->rc_state = RC_DONE; 299 /* 300 * If we have a valid reply update status and save 301 * the reply for non-idempotent rpc's. 302 */ 303 if (repvalid && nonidempotent[nd->nd_procnum]) { 304 if ((nd->nd_flag & ND_NFSV3) == 0 && 305 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 306 rp->rc_status = nd->nd_repstat; 307 rp->rc_flag |= RC_REPSTATUS; 308 } else { 309 rp->rc_reply = m_copym(repmbuf, 310 0, M_COPYALL, MB_WAIT); 311 rp->rc_flag |= RC_REPMBUF; 312 } 313 } 314 rp->rc_flag &= ~RC_LOCKED; 315 if (rp->rc_flag & RC_WANTED) { 316 rp->rc_flag &= ~RC_WANTED; 317 wakeup((caddr_t)rp); 318 } 319 return; 320 } 321 } 322 NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff)); 323 } 324 325 /* 326 * Clean out the cache. Called when the last nfsd terminates. 327 */ 328 void 329 nfsrv_cleancache(void) 330 { 331 struct nfsrvcache *rp, *nextrp; 332 333 TAILQ_FOREACH_MUTABLE(rp, &nfsrvlruhead, rc_lru, nextrp) { 334 LIST_REMOVE(rp, rc_hash); 335 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 336 if (rp->rc_flag & RC_REPMBUF) 337 m_freem(rp->rc_reply); 338 if (rp->rc_flag & RC_NAM) 339 kfree(rp->rc_nam, M_SONAME); 340 kfree(rp, M_NFSD); 341 } 342 numnfsrvcache = 0; 343 } 344 345 #endif /* NFS_NOSERVER */ 346