nfs_srvcache.c revision 1.31.12.1
1 /* $NetBSD: nfs_srvcache.c,v 1.31.12.1 2006/12/30 20:50:52 yamt Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software contributed to Berkeley by 8 * Rick Macklem at The University of Guelph. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)nfs_srvcache.c 8.3 (Berkeley) 3/30/95 35 */ 36 37 /* 38 * Reference: Chet Juszczak, "Improving the Performance and Correctness 39 * of an NFS Server", in Proc. Winter 1989 USENIX Conference, 40 * pages 53-63. San Diego, February 1989. 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: nfs_srvcache.c,v 1.31.12.1 2006/12/30 20:50:52 yamt Exp $"); 45 46 #include "opt_iso.h" 47 48 #include <sys/param.h> 49 #include <sys/vnode.h> 50 #include <sys/mount.h> 51 #include <sys/kernel.h> 52 #include <sys/systm.h> 53 #include <sys/lock.h> 54 #include <sys/proc.h> 55 #include <sys/pool.h> 56 #include <sys/mbuf.h> 57 #include <sys/malloc.h> 58 #include <sys/socket.h> 59 #include <sys/socketvar.h> 60 61 #include <netinet/in.h> 62 #ifdef ISO 63 #include <netiso/iso.h> 64 #endif 65 #include <nfs/nfsm_subs.h> 66 #include <nfs/rpcv2.h> 67 #include <nfs/nfsproto.h> 68 #include <nfs/nfs.h> 69 #include <nfs/nfsrvcache.h> 70 #include <nfs/nfs_var.h> 71 72 extern struct nfsstats nfsstats; 73 extern const int nfsv2_procid[NFS_NPROCS]; 74 long numnfsrvcache, desirednfsrvcache = NFSRVCACHESIZ; 75 struct pool nfs_reqcache_pool; 76 77 #define NFSRCHASH(xid) \ 78 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) 79 LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; 80 TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; 81 struct simplelock nfsrv_reqcache_lock = SIMPLELOCK_INITIALIZER; 82 u_long nfsrvhash; 83 84 #define NETFAMILY(rp) \ 85 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) 86 87 static struct nfsrvcache *nfsrv_lookupcache(struct nfsrv_descript *nd); 88 static void nfsrv_unlockcache(struct nfsrvcache *rp); 89 90 /* 91 * Static array that defines which nfs rpc's are nonidempotent 92 */ 93 const int nonidempotent[NFS_NPROCS] = { 94 FALSE, /* NULL */ 95 FALSE, /* GETATTR */ 96 TRUE, /* SETATTR */ 97 FALSE, /* LOOKUP */ 98 FALSE, /* ACCESS */ 99 FALSE, /* READLINK */ 100 FALSE, /* READ */ 101 TRUE, /* WRITE */ 102 TRUE, /* CREATE */ 103 TRUE, /* MKDIR */ 104 TRUE, /* SYMLINK */ 105 TRUE, /* MKNOD */ 106 TRUE, /* REMOVE */ 107 TRUE, /* RMDIR */ 108 TRUE, /* RENAME */ 109 TRUE, /* LINK */ 110 FALSE, /* READDIR */ 111 FALSE, /* READDIRPLUS */ 112 FALSE, /* FSSTAT */ 113 FALSE, /* FSINFO */ 114 FALSE, /* PATHCONF */ 115 FALSE, /* COMMIT */ 116 FALSE, /* NOOP */ 117 }; 118 119 /* True iff the rpc reply is an nfs status ONLY! */ 120 static const int nfsv2_repstat[NFS_NPROCS] = { 121 FALSE, /* NULL */ 122 FALSE, /* GETATTR */ 123 FALSE, /* SETATTR */ 124 FALSE, /* NOOP */ 125 FALSE, /* LOOKUP */ 126 FALSE, /* READLINK */ 127 FALSE, /* READ */ 128 FALSE, /* Obsolete WRITECACHE */ 129 FALSE, /* WRITE */ 130 FALSE, /* CREATE */ 131 TRUE, /* REMOVE */ 132 TRUE, /* RENAME */ 133 TRUE, /* LINK */ 134 TRUE, /* SYMLINK */ 135 FALSE, /* MKDIR */ 136 TRUE, /* RMDIR */ 137 FALSE, /* READDIR */ 138 FALSE, /* STATFS */ 139 }; 140 141 /* 142 * Initialize the server request cache list 143 */ 144 void 145 nfsrv_initcache() 146 { 147 148 nfsrvhashtbl = hashinit(desirednfsrvcache, HASH_LIST, M_NFSD, 149 M_WAITOK, &nfsrvhash); 150 TAILQ_INIT(&nfsrvlruhead); 151 pool_init(&nfs_reqcache_pool, sizeof(struct nfsrvcache), 0, 0, 0, 152 "nfsreqcachepl", &pool_allocator_nointr); 153 } 154 155 /* 156 * Lookup a cache and lock it 157 */ 158 static struct nfsrvcache * 159 nfsrv_lookupcache(nd) 160 struct nfsrv_descript *nd; 161 { 162 struct nfsrvcache *rp; 163 164 LOCK_ASSERT(simple_lock_held(&nfsrv_reqcache_lock)); 165 166 loop: 167 LIST_FOREACH(rp, NFSRCHASH(nd->nd_retxid), rc_hash) { 168 if (nd->nd_retxid == rp->rc_xid && 169 nd->nd_procnum == rp->rc_proc && 170 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 171 if ((rp->rc_flag & RC_LOCKED) != 0) { 172 rp->rc_flag |= RC_WANTED; 173 (void) ltsleep(rp, PZERO - 1, "nfsrc", 0, 174 &nfsrv_reqcache_lock); 175 goto loop; 176 } 177 rp->rc_flag |= RC_LOCKED; 178 break; 179 } 180 } 181 182 return rp; 183 } 184 185 /* 186 * Unlock a cache 187 */ 188 static void 189 nfsrv_unlockcache(rp) 190 struct nfsrvcache *rp; 191 { 192 193 LOCK_ASSERT(simple_lock_held(&nfsrv_reqcache_lock)); 194 195 rp->rc_flag &= ~RC_LOCKED; 196 if (rp->rc_flag & RC_WANTED) { 197 rp->rc_flag &= ~RC_WANTED; 198 wakeup(rp); 199 } 200 } 201 202 /* 203 * Look for the request in the cache 204 * If found then 205 * return action and optionally reply 206 * else 207 * insert it in the cache 208 * 209 * The rules are as follows: 210 * - if in progress, return DROP request 211 * - if completed within DELAY of the current time, return DROP it 212 * - if completed a longer time ago return REPLY if the reply was cached or 213 * return DOIT 214 * Update/add new request at end of lru list 215 */ 216 int 217 nfsrv_getcache(nd, slp, repp) 218 struct nfsrv_descript *nd; 219 struct nfssvc_sock *slp; 220 struct mbuf **repp; 221 { 222 struct nfsrvcache *rp, *rpdup; 223 struct mbuf *mb; 224 struct sockaddr_in *saddr; 225 caddr_t bpos; 226 int ret; 227 228 simple_lock(&nfsrv_reqcache_lock); 229 rp = nfsrv_lookupcache(nd); 230 if (rp) { 231 simple_unlock(&nfsrv_reqcache_lock); 232 found: 233 /* If not at end of LRU chain, move it there */ 234 if (TAILQ_NEXT(rp, rc_lru)) { /* racy but ok */ 235 simple_lock(&nfsrv_reqcache_lock); 236 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 237 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 238 simple_unlock(&nfsrv_reqcache_lock); 239 } 240 if (rp->rc_state == RC_UNUSED) 241 panic("nfsrv cache"); 242 if (rp->rc_state == RC_INPROG) { 243 nfsstats.srvcache_inproghits++; 244 ret = RC_DROPIT; 245 } else if (rp->rc_flag & RC_REPSTATUS) { 246 nfsstats.srvcache_nonidemdonehits++; 247 nfs_rephead(0, nd, slp, rp->rc_status, 248 0, (u_quad_t *)0, repp, &mb, &bpos); 249 ret = RC_REPLY; 250 } else if (rp->rc_flag & RC_REPMBUF) { 251 nfsstats.srvcache_nonidemdonehits++; 252 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 253 M_WAIT); 254 ret = RC_REPLY; 255 } else { 256 nfsstats.srvcache_idemdonehits++; 257 rp->rc_state = RC_INPROG; 258 ret = RC_DOIT; 259 } 260 simple_lock(&nfsrv_reqcache_lock); 261 nfsrv_unlockcache(rp); 262 simple_unlock(&nfsrv_reqcache_lock); 263 return ret; 264 } 265 nfsstats.srvcache_misses++; 266 if (numnfsrvcache < desirednfsrvcache) { 267 numnfsrvcache++; 268 simple_unlock(&nfsrv_reqcache_lock); 269 rp = pool_get(&nfs_reqcache_pool, PR_WAITOK); 270 memset(rp, 0, sizeof *rp); 271 rp->rc_flag = RC_LOCKED; 272 } else { 273 rp = TAILQ_FIRST(&nfsrvlruhead); 274 while ((rp->rc_flag & RC_LOCKED) != 0) { 275 rp->rc_flag |= RC_WANTED; 276 (void) ltsleep(rp, PZERO-1, "nfsrc", 0, 277 &nfsrv_reqcache_lock); 278 rp = TAILQ_FIRST(&nfsrvlruhead); 279 } 280 rp->rc_flag |= RC_LOCKED; 281 LIST_REMOVE(rp, rc_hash); 282 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 283 simple_unlock(&nfsrv_reqcache_lock); 284 if (rp->rc_flag & RC_REPMBUF) 285 m_freem(rp->rc_reply); 286 if (rp->rc_flag & RC_NAM) 287 (void) m_free(rp->rc_nam); 288 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 289 } 290 rp->rc_state = RC_INPROG; 291 rp->rc_xid = nd->nd_retxid; 292 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 293 switch (saddr->sin_family) { 294 case AF_INET: 295 rp->rc_flag |= RC_INETADDR; 296 rp->rc_inetaddr = saddr->sin_addr.s_addr; 297 break; 298 case AF_ISO: 299 default: 300 rp->rc_flag |= RC_NAM; 301 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 302 break; 303 }; 304 rp->rc_proc = nd->nd_procnum; 305 simple_lock(&nfsrv_reqcache_lock); 306 rpdup = nfsrv_lookupcache(nd); 307 if (rpdup != NULL) { 308 /* 309 * other thread made duplicate cache entry. 310 */ 311 simple_unlock(&nfsrv_reqcache_lock); 312 pool_put(&nfs_reqcache_pool, rp); 313 rp = rpdup; 314 goto found; 315 } 316 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 317 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 318 nfsrv_unlockcache(rp); 319 simple_unlock(&nfsrv_reqcache_lock); 320 return RC_DOIT; 321 } 322 323 /* 324 * Update a request cache entry after the rpc has been done 325 */ 326 void 327 nfsrv_updatecache(nd, repvalid, repmbuf) 328 struct nfsrv_descript *nd; 329 int repvalid; 330 struct mbuf *repmbuf; 331 { 332 struct nfsrvcache *rp; 333 334 if (!nd->nd_nam2) 335 return; 336 simple_lock(&nfsrv_reqcache_lock); 337 rp = nfsrv_lookupcache(nd); 338 simple_unlock(&nfsrv_reqcache_lock); 339 if (rp) { 340 rp->rc_state = RC_DONE; 341 /* 342 * If we have a valid reply update status and save 343 * the reply for non-idempotent rpc's. 344 */ 345 if (repvalid && nonidempotent[nd->nd_procnum]) { 346 if ((nd->nd_flag & ND_NFSV3) == 0 && 347 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 348 rp->rc_status = nd->nd_repstat; 349 rp->rc_flag |= RC_REPSTATUS; 350 } else { 351 rp->rc_reply = m_copym(repmbuf, 352 0, M_COPYALL, M_WAIT); 353 rp->rc_flag |= RC_REPMBUF; 354 } 355 } 356 simple_lock(&nfsrv_reqcache_lock); 357 nfsrv_unlockcache(rp); 358 simple_unlock(&nfsrv_reqcache_lock); 359 } 360 } 361 362 /* 363 * Clean out the cache. Called when the last nfsd terminates. 364 */ 365 void 366 nfsrv_cleancache() 367 { 368 struct nfsrvcache *rp, *nextrp; 369 370 simple_lock(&nfsrv_reqcache_lock); 371 for (rp = TAILQ_FIRST(&nfsrvlruhead); rp != 0; rp = nextrp) { 372 nextrp = TAILQ_NEXT(rp, rc_lru); 373 LIST_REMOVE(rp, rc_hash); 374 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 375 pool_put(&nfs_reqcache_pool, rp); 376 } 377 numnfsrvcache = 0; 378 simple_unlock(&nfsrv_reqcache_lock); 379 } 380
Indexes created Fri Sep 26 20:09:58 GMT 2025