nfs_srvcache.c revision 1.34
1 /* $NetBSD: nfs_srvcache.c,v 1.34 2007/01/17 12:40:08 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 1.34 2007/01/17 12:40:08 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 static void 142 cleanentry(struct nfsrvcache *rp) 143 { 144 145 if ((rp->rc_flag & RC_REPMBUF) != 0) { 146 m_freem(rp->rc_reply); 147 } 148 if ((rp->rc_flag & RC_NAM) != 0) { 149 m_free(rp->rc_nam); 150 } 151 rp->rc_flag &= ~(RC_REPSTATUS|RC_REPMBUF); 152 } 153 154 /* 155 * Initialize the server request cache list 156 */ 157 void 158 nfsrv_initcache() 159 { 160 161 nfsrvhashtbl = hashinit(desirednfsrvcache, HASH_LIST, M_NFSD, 162 M_WAITOK, &nfsrvhash); 163 TAILQ_INIT(&nfsrvlruhead); 164 pool_init(&nfs_reqcache_pool, sizeof(struct nfsrvcache), 0, 0, 0, 165 "nfsreqcachepl", &pool_allocator_nointr); 166 } 167 168 /* 169 * Lookup a cache and lock it 170 */ 171 static struct nfsrvcache * 172 nfsrv_lookupcache(nd) 173 struct nfsrv_descript *nd; 174 { 175 struct nfsrvcache *rp; 176 177 LOCK_ASSERT(simple_lock_held(&nfsrv_reqcache_lock)); 178 179 loop: 180 LIST_FOREACH(rp, NFSRCHASH(nd->nd_retxid), rc_hash) { 181 if (nd->nd_retxid == rp->rc_xid && 182 nd->nd_procnum == rp->rc_proc && 183 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { 184 if ((rp->rc_flag & RC_LOCKED) != 0) { 185 rp->rc_flag |= RC_WANTED; 186 (void) ltsleep(rp, PZERO - 1, "nfsrc", 0, 187 &nfsrv_reqcache_lock); 188 goto loop; 189 } 190 rp->rc_flag |= RC_LOCKED; 191 break; 192 } 193 } 194 195 return rp; 196 } 197 198 /* 199 * Unlock a cache 200 */ 201 static void 202 nfsrv_unlockcache(rp) 203 struct nfsrvcache *rp; 204 { 205 206 LOCK_ASSERT(simple_lock_held(&nfsrv_reqcache_lock)); 207 208 rp->rc_flag &= ~RC_LOCKED; 209 if (rp->rc_flag & RC_WANTED) { 210 rp->rc_flag &= ~RC_WANTED; 211 wakeup(rp); 212 } 213 } 214 215 /* 216 * Look for the request in the cache 217 * If found then 218 * return action and optionally reply 219 * else 220 * insert it in the cache 221 * 222 * The rules are as follows: 223 * - if in progress, return DROP request 224 * - if completed within DELAY of the current time, return DROP it 225 * - if completed a longer time ago return REPLY if the reply was cached or 226 * return DOIT 227 * Update/add new request at end of lru list 228 */ 229 int 230 nfsrv_getcache(nd, slp, repp) 231 struct nfsrv_descript *nd; 232 struct nfssvc_sock *slp; 233 struct mbuf **repp; 234 { 235 struct nfsrvcache *rp, *rpdup; 236 struct mbuf *mb; 237 struct sockaddr_in *saddr; 238 caddr_t bpos; 239 int ret; 240 241 simple_lock(&nfsrv_reqcache_lock); 242 rp = nfsrv_lookupcache(nd); 243 if (rp) { 244 simple_unlock(&nfsrv_reqcache_lock); 245 found: 246 /* If not at end of LRU chain, move it there */ 247 if (TAILQ_NEXT(rp, rc_lru)) { /* racy but ok */ 248 simple_lock(&nfsrv_reqcache_lock); 249 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 250 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 251 simple_unlock(&nfsrv_reqcache_lock); 252 } 253 if (rp->rc_state == RC_UNUSED) 254 panic("nfsrv cache"); 255 if (rp->rc_state == RC_INPROG) { 256 nfsstats.srvcache_inproghits++; 257 ret = RC_DROPIT; 258 } else if (rp->rc_flag & RC_REPSTATUS) { 259 nfsstats.srvcache_nonidemdonehits++; 260 nfs_rephead(0, nd, slp, rp->rc_status, 261 0, (u_quad_t *)0, repp, &mb, &bpos); 262 ret = RC_REPLY; 263 } else if (rp->rc_flag & RC_REPMBUF) { 264 nfsstats.srvcache_nonidemdonehits++; 265 *repp = m_copym(rp->rc_reply, 0, M_COPYALL, 266 M_WAIT); 267 ret = RC_REPLY; 268 } else { 269 nfsstats.srvcache_idemdonehits++; 270 rp->rc_state = RC_INPROG; 271 ret = RC_DOIT; 272 } 273 simple_lock(&nfsrv_reqcache_lock); 274 nfsrv_unlockcache(rp); 275 simple_unlock(&nfsrv_reqcache_lock); 276 return ret; 277 } 278 nfsstats.srvcache_misses++; 279 if (numnfsrvcache < desirednfsrvcache) { 280 numnfsrvcache++; 281 simple_unlock(&nfsrv_reqcache_lock); 282 rp = pool_get(&nfs_reqcache_pool, PR_WAITOK); 283 memset(rp, 0, sizeof *rp); 284 rp->rc_flag = RC_LOCKED; 285 } else { 286 rp = TAILQ_FIRST(&nfsrvlruhead); 287 while ((rp->rc_flag & RC_LOCKED) != 0) { 288 rp->rc_flag |= RC_WANTED; 289 (void) ltsleep(rp, PZERO-1, "nfsrc", 0, 290 &nfsrv_reqcache_lock); 291 rp = TAILQ_FIRST(&nfsrvlruhead); 292 } 293 rp->rc_flag |= RC_LOCKED; 294 LIST_REMOVE(rp, rc_hash); 295 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 296 simple_unlock(&nfsrv_reqcache_lock); 297 cleanentry(rp); 298 rp->rc_flag &= (RC_LOCKED | RC_WANTED); 299 } 300 rp->rc_state = RC_INPROG; 301 rp->rc_xid = nd->nd_retxid; 302 saddr = mtod(nd->nd_nam, struct sockaddr_in *); 303 switch (saddr->sin_family) { 304 case AF_INET: 305 rp->rc_flag |= RC_INETADDR; 306 rp->rc_inetaddr = saddr->sin_addr.s_addr; 307 break; 308 case AF_ISO: 309 default: 310 rp->rc_flag |= RC_NAM; 311 rp->rc_nam = m_copym(nd->nd_nam, 0, M_COPYALL, M_WAIT); 312 break; 313 }; 314 rp->rc_proc = nd->nd_procnum; 315 simple_lock(&nfsrv_reqcache_lock); 316 rpdup = nfsrv_lookupcache(nd); 317 if (rpdup != NULL) { 318 /* 319 * other thread made duplicate cache entry. 320 */ 321 simple_unlock(&nfsrv_reqcache_lock); 322 pool_put(&nfs_reqcache_pool, rp); 323 rp = rpdup; 324 goto found; 325 } 326 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); 327 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); 328 nfsrv_unlockcache(rp); 329 simple_unlock(&nfsrv_reqcache_lock); 330 return RC_DOIT; 331 } 332 333 /* 334 * Update a request cache entry after the rpc has been done 335 */ 336 void 337 nfsrv_updatecache(nd, repvalid, repmbuf) 338 struct nfsrv_descript *nd; 339 int repvalid; 340 struct mbuf *repmbuf; 341 { 342 struct nfsrvcache *rp; 343 344 if (!nd->nd_nam2) 345 return; 346 simple_lock(&nfsrv_reqcache_lock); 347 rp = nfsrv_lookupcache(nd); 348 simple_unlock(&nfsrv_reqcache_lock); 349 if (rp) { 350 cleanentry(rp); 351 rp->rc_state = RC_DONE; 352 /* 353 * If we have a valid reply update status and save 354 * the reply for non-idempotent rpc's. 355 */ 356 if (repvalid && nonidempotent[nd->nd_procnum]) { 357 if ((nd->nd_flag & ND_NFSV3) == 0 && 358 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { 359 rp->rc_status = nd->nd_repstat; 360 rp->rc_flag |= RC_REPSTATUS; 361 } else { 362 rp->rc_reply = m_copym(repmbuf, 363 0, M_COPYALL, M_WAIT); 364 rp->rc_flag |= RC_REPMBUF; 365 } 366 } 367 simple_lock(&nfsrv_reqcache_lock); 368 nfsrv_unlockcache(rp); 369 simple_unlock(&nfsrv_reqcache_lock); 370 } 371 } 372 373 /* 374 * Clean out the cache. Called when the last nfsd terminates. 375 */ 376 void 377 nfsrv_cleancache() 378 { 379 struct nfsrvcache *rp, *nextrp; 380 381 simple_lock(&nfsrv_reqcache_lock); 382 for (rp = TAILQ_FIRST(&nfsrvlruhead); rp != 0; rp = nextrp) { 383 nextrp = TAILQ_NEXT(rp, rc_lru); 384 LIST_REMOVE(rp, rc_hash); 385 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); 386 KASSERT((rp->rc_flag & (RC_LOCKED|RC_WANTED)) == 0); 387 cleanentry(rp); 388 pool_put(&nfs_reqcache_pool, rp); 389 } 390 numnfsrvcache = 0; 391 simple_unlock(&nfsrv_reqcache_lock); 392 } 393
Indexes created Fri Sep 26 08:10:20 GMT 2025