| 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 1.9 2004/08/02 13:22:34 joerg 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 | extern struct nfsstats nfsstats; |
| 62 | extern int nfsv2_procid[NFS_NPROCS]; |
| 63 | static long numnfsrvcache; |
| 64 | static long desirednfsrvcache = NFSRVCACHESIZ; |
| 65 | |
| 66 | #define NFSRCHASH(xid) \ |
| 67 | (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash]) |
| 68 | static LIST_HEAD(nfsrvhash, nfsrvcache) *nfsrvhashtbl; |
| 69 | static TAILQ_HEAD(nfsrvlru, nfsrvcache) nfsrvlruhead; |
| 70 | static u_long nfsrvhash; |
| 71 | |
| 72 | #define TRUE 1 |
| 73 | #define FALSE 0 |
| 74 | |
| 75 | #define NETFAMILY(rp) \ |
| 76 | (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO) |
| 77 | |
| 78 | /* |
| 79 | * Static array that defines which nfs rpc's are nonidempotent |
| 80 | */ |
| 81 | static int nonidempotent[NFS_NPROCS] = { |
| 82 | FALSE, |
| 83 | FALSE, |
| 84 | TRUE, |
| 85 | FALSE, |
| 86 | FALSE, |
| 87 | FALSE, |
| 88 | FALSE, |
| 89 | TRUE, |
| 90 | TRUE, |
| 91 | TRUE, |
| 92 | TRUE, |
| 93 | TRUE, |
| 94 | TRUE, |
| 95 | TRUE, |
| 96 | TRUE, |
| 97 | TRUE, |
| 98 | FALSE, |
| 99 | FALSE, |
| 100 | FALSE, |
| 101 | FALSE, |
| 102 | FALSE, |
| 103 | FALSE, |
| 104 | FALSE, |
| 105 | FALSE, |
| 106 | FALSE, |
| 107 | FALSE, |
| 108 | }; |
| 109 | |
| 110 | /* True iff the rpc reply is an nfs status ONLY! */ |
| 111 | static int nfsv2_repstat[NFS_NPROCS] = { |
| 112 | FALSE, |
| 113 | FALSE, |
| 114 | FALSE, |
| 115 | FALSE, |
| 116 | FALSE, |
| 117 | FALSE, |
| 118 | FALSE, |
| 119 | FALSE, |
| 120 | FALSE, |
| 121 | FALSE, |
| 122 | TRUE, |
| 123 | TRUE, |
| 124 | TRUE, |
| 125 | TRUE, |
| 126 | FALSE, |
| 127 | TRUE, |
| 128 | FALSE, |
| 129 | FALSE, |
| 130 | }; |
| 131 | |
| 132 | /* |
| 133 | * Initialize the server request cache list |
| 134 | */ |
| 135 | void |
| 136 | nfsrv_initcache(void) |
| 137 | { |
| 138 | |
| 139 | nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash); |
| 140 | TAILQ_INIT(&nfsrvlruhead); |
| 141 | } |
| 142 | |
| 143 | /* |
| 144 | * Look for the request in the cache |
| 145 | * If found then |
| 146 | * return action and optionally reply |
| 147 | * else |
| 148 | * insert it in the cache |
| 149 | * |
| 150 | * The rules are as follows: |
| 151 | * - if in progress, return DROP request |
| 152 | * - if completed within DELAY of the current time, return DROP it |
| 153 | * - if completed a longer time ago return REPLY if the reply was cached or |
| 154 | * return DOIT |
| 155 | * Update/add new request at end of lru list |
| 156 | */ |
| 157 | int |
| 158 | nfsrv_getcache(struct nfsrv_descript *nd, struct nfssvc_sock *slp, |
| 159 | struct mbuf **repp) |
| 160 | { |
| 161 | struct nfsrvcache *rp; |
| 162 | struct mbuf *mb; |
| 163 | struct sockaddr_in *saddr; |
| 164 | caddr_t bpos; |
| 165 | int ret; |
| 166 | |
| 167 | /* |
| 168 | * Don't cache recent requests for reliable transport protocols. |
| 169 | * (Maybe we should for the case of a reconnect, but..) |
| 170 | */ |
| 171 | if (!nd->nd_nam2) |
| 172 | return (RC_DOIT); |
| 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 | (void) 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 | 0, (u_quad_t *)0, 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 | return (ret); |
| 216 | } |
| 217 | } |
| 218 | nfsstats.srvcache_misses++; |
| 219 | NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff)); |
| 220 | if (numnfsrvcache < desirednfsrvcache) { |
| 221 | rp = (struct nfsrvcache *)malloc((u_long)sizeof *rp, |
| 222 | M_NFSD, M_WAITOK); |
| 223 | bzero((char *)rp, sizeof *rp); |
| 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 | (void) 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 | if (rp->rc_flag & RC_NAM) |
| 239 | FREE(rp->rc_nam, M_SONAME); |
| 240 | rp->rc_flag &= (RC_LOCKED | RC_WANTED); |
| 241 | } |
| 242 | TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru); |
| 243 | rp->rc_state = RC_INPROG; |
| 244 | rp->rc_xid = nd->nd_retxid; |
| 245 | saddr = (struct sockaddr_in *)nd->nd_nam; |
| 246 | switch (saddr->sin_family) { |
| 247 | case AF_INET: |
| 248 | rp->rc_flag |= RC_INETADDR; |
| 249 | rp->rc_inetaddr = saddr->sin_addr.s_addr; |
| 250 | break; |
| 251 | case AF_ISO: |
| 252 | default: |
| 253 | rp->rc_flag |= RC_NAM; |
| 254 | rp->rc_nam = dup_sockaddr(nd->nd_nam); |
| 255 | break; |
| 256 | }; |
| 257 | rp->rc_proc = nd->nd_procnum; |
| 258 | LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash); |
| 259 | rp->rc_flag &= ~RC_LOCKED; |
| 260 | if (rp->rc_flag & RC_WANTED) { |
| 261 | rp->rc_flag &= ~RC_WANTED; |
| 262 | wakeup((caddr_t)rp); |
| 263 | } |
| 264 | return (RC_DOIT); |
| 265 | } |
| 266 | |
| 267 | /* |
| 268 | * Update a request cache entry after the rpc has been done |
| 269 | */ |
| 270 | void |
| 271 | nfsrv_updatecache(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf) |
| 272 | { |
| 273 | struct nfsrvcache *rp; |
| 274 | |
| 275 | if (!nd->nd_nam2) |
| 276 | return; |
| 277 | loop: |
| 278 | for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0; |
| 279 | rp = rp->rc_hash.le_next) { |
| 280 | if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc && |
| 281 | netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) { |
| 282 | NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff)); |
| 283 | if ((rp->rc_flag & RC_LOCKED) != 0) { |
| 284 | rp->rc_flag |= RC_WANTED; |
| 285 | (void) tsleep((caddr_t)rp, 0, "nfsrc", 0); |
| 286 | goto loop; |
| 287 | } |
| 288 | rp->rc_flag |= RC_LOCKED; |
| 289 | if (rp->rc_state == RC_DONE) { |
| 290 | /* |
| 291 | * This can occur if the cache is too small. |
| 292 | * Retransmits of the same request aren't |
| 293 | * dropped so we may see the operation |
| 294 | * complete more then once. |
| 295 | */ |
| 296 | if (rp->rc_flag & RC_REPMBUF) { |
| 297 | m_freem(rp->rc_reply); |
| 298 | rp->rc_flag &= ~RC_REPMBUF; |
| 299 | } |
| 300 | } |
| 301 | rp->rc_state = RC_DONE; |
| 302 | /* |
| 303 | * If we have a valid reply update status and save |
| 304 | * the reply for non-idempotent rpc's. |
| 305 | */ |
| 306 | if (repvalid && nonidempotent[nd->nd_procnum]) { |
| 307 | if ((nd->nd_flag & ND_NFSV3) == 0 && |
| 308 | nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) { |
| 309 | rp->rc_status = nd->nd_repstat; |
| 310 | rp->rc_flag |= RC_REPSTATUS; |
| 311 | } else { |
| 312 | rp->rc_reply = m_copym(repmbuf, |
| 313 | 0, M_COPYALL, MB_WAIT); |
| 314 | rp->rc_flag |= RC_REPMBUF; |
| 315 | } |
| 316 | } |
| 317 | rp->rc_flag &= ~RC_LOCKED; |
| 318 | if (rp->rc_flag & RC_WANTED) { |
| 319 | rp->rc_flag &= ~RC_WANTED; |
| 320 | wakeup((caddr_t)rp); |
| 321 | } |
| 322 | return; |
| 323 | } |
| 324 | } |
| 325 | NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff)); |
| 326 | } |
| 327 | |
| 328 | /* |
| 329 | * Clean out the cache. Called when the last nfsd terminates. |
| 330 | */ |
| 331 | void |
| 332 | nfsrv_cleancache(void) |
| 333 | { |
| 334 | struct nfsrvcache *rp, *nextrp; |
| 335 | |
| 336 | TAILQ_FOREACH_MUTABLE(rp, &nfsrvlruhead, rc_lru, nextrp) { |
| 337 | LIST_REMOVE(rp, rc_hash); |
| 338 | TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru); |
| 339 | if (rp->rc_flag & RC_REPMBUF) |
| 340 | m_freem(rp->rc_reply); |
| 341 | if (rp->rc_flag & RC_NAM) |
| 342 | free(rp->rc_nam, M_SONAME); |
| 343 | free(rp, M_NFSD); |
| 344 | } |
| 345 | numnfsrvcache = 0; |
| 346 | } |
| 347 | |
| 348 | #endif /* NFS_NOSERVER */ |