2 * Copyright (c) 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Rick Macklem at The University of Guelph.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
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 $
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.
46 #include <sys/param.h>
47 #include <sys/malloc.h>
48 #include <sys/mount.h>
49 #include <sys/systm.h>
51 #include <sys/socket.h>
52 #include <sys/socketvar.h> /* for dup_sockaddr */
54 #include <netinet/in.h>
58 #include "nfsrvcache.h"
61 static long numnfsrvcache;
62 static long desirednfsrvcache = NFSRVCACHESIZ;
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;
73 #define NETFAMILY(rp) \
74 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO)
76 struct lwkt_token srvcache_token = LWKT_TOKEN_INITIALIZER(srvcache_token);
79 * Static array that defines which nfs rpc's are nonidempotent
81 static int nonidempotent[NFS_NPROCS] = {
110 /* True iff the rpc reply is an nfs status ONLY! */
111 static int nfsv2_repstat[NFS_NPROCS] = {
133 * Initialize the server request cache list
136 nfsrv_initcache(void)
138 nfsrvhashtbl = hashinit(desirednfsrvcache, M_NFSD, &nfsrvhash);
139 TAILQ_INIT(&nfsrvlruhead);
143 * Look for the request in the cache
145 * return action and optionally reply
147 * insert it in the cache
149 * The rules are as follows:
150 * - if in progress, return DROP request
151 * - if completed within DELAY of the current time, return DROP it
152 * - if completed a longer time ago return REPLY if the reply was cached or
154 * Update/add new request at end of lru list
157 nfsrv_getcache(struct nfsrv_descript *nd, struct nfssvc_sock *slp,
160 struct nfsrvcache *rp;
162 struct sockaddr_in *saddr;
167 * Don't cache recent requests for reliable transport protocols.
168 * (Maybe we should for the case of a reconnect, but..)
173 lwkt_gettoken(&srvcache_token);
175 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0;
176 rp = rp->rc_hash.le_next) {
177 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
178 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) {
179 NFS_DPF(RC, ("H%03x", rp->rc_xid & 0xfff));
180 if ((rp->rc_flag & RC_LOCKED) != 0) {
181 rp->rc_flag |= RC_WANTED;
182 tsleep((caddr_t)rp, 0, "nfsrc", 0);
185 rp->rc_flag |= RC_LOCKED;
186 /* If not at end of LRU chain, move it there */
187 if (TAILQ_NEXT(rp, rc_lru) != NULL) {
188 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
189 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
191 if (rp->rc_state == RC_UNUSED)
192 panic("nfsrv cache");
193 if (rp->rc_state == RC_INPROG) {
194 nfsstats.srvcache_inproghits++;
196 } else if (rp->rc_flag & RC_REPSTATUS) {
197 nfsstats.srvcache_nonidemdonehits++;
198 nfs_rephead(0, nd, slp, rp->rc_status,
201 } else if (rp->rc_flag & RC_REPMBUF) {
202 nfsstats.srvcache_nonidemdonehits++;
203 *repp = m_copym(rp->rc_reply, 0, M_COPYALL,
207 nfsstats.srvcache_idemdonehits++;
208 rp->rc_state = RC_INPROG;
211 rp->rc_flag &= ~RC_LOCKED;
212 if (rp->rc_flag & RC_WANTED) {
213 rp->rc_flag &= ~RC_WANTED;
216 lwkt_reltoken(&srvcache_token);
221 nfsstats.srvcache_misses++;
222 NFS_DPF(RC, ("M%03x", nd->nd_retxid & 0xfff));
223 if (numnfsrvcache < desirednfsrvcache) {
224 rp = kmalloc((u_long)sizeof *rp, M_NFSD, M_WAITOK | M_ZERO);
226 rp->rc_flag = RC_LOCKED;
228 rp = TAILQ_FIRST(&nfsrvlruhead);
229 while ((rp->rc_flag & RC_LOCKED) != 0) {
230 rp->rc_flag |= RC_WANTED;
231 tsleep((caddr_t)rp, 0, "nfsrc", 0);
232 rp = TAILQ_FIRST(&nfsrvlruhead);
234 rp->rc_flag |= RC_LOCKED;
235 LIST_REMOVE(rp, rc_hash);
236 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
237 if (rp->rc_flag & RC_REPMBUF) {
238 m_freem(rp->rc_reply);
240 rp->rc_flag &= ~RC_REPMBUF;
242 if (rp->rc_flag & RC_NAM) {
243 FREE(rp->rc_nam, M_SONAME);
245 rp->rc_flag &= ~RC_NAM;
248 TAILQ_INSERT_TAIL(&nfsrvlruhead, rp, rc_lru);
250 rp->rc_state = RC_INPROG;
251 rp->rc_xid = nd->nd_retxid;
252 saddr = (struct sockaddr_in *)nd->nd_nam;
253 switch (saddr->sin_family) {
255 rp->rc_flag |= RC_INETADDR;
256 rp->rc_inetaddr = saddr->sin_addr.s_addr;
260 rp->rc_flag |= RC_NAM;
261 rp->rc_nam = dup_sockaddr(nd->nd_nam);
264 rp->rc_proc = nd->nd_procnum;
265 LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash);
266 rp->rc_flag &= ~RC_LOCKED;
267 if (rp->rc_flag & RC_WANTED) {
268 rp->rc_flag &= ~RC_WANTED;
271 lwkt_reltoken(&srvcache_token);
277 * Update a request cache entry after the rpc has been done
280 nfsrv_updatecache(struct nfsrv_descript *nd, int repvalid, struct mbuf *repmbuf)
282 struct nfsrvcache *rp;
287 lwkt_gettoken(&srvcache_token);
289 for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0;
290 rp = rp->rc_hash.le_next) {
291 if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
292 netaddr_match(NETFAMILY(rp), &rp->rc_haddr, nd->nd_nam)) {
293 NFS_DPF(RC, ("U%03x", rp->rc_xid & 0xfff));
294 if ((rp->rc_flag & RC_LOCKED) != 0) {
295 rp->rc_flag |= RC_WANTED;
296 tsleep((caddr_t)rp, 0, "nfsrc", 0);
299 rp->rc_flag |= RC_LOCKED;
300 if (rp->rc_state == RC_DONE) {
302 * This can occur if the cache is too small.
303 * Retransmits of the same request aren't
304 * dropped so we may see the operation
305 * complete more then once.
307 if (rp->rc_flag & RC_REPMBUF) {
308 m_freem(rp->rc_reply);
310 rp->rc_flag &= ~RC_REPMBUF;
313 rp->rc_state = RC_DONE;
316 * If we have a valid reply update status and save
317 * the reply for non-idempotent rpc's.
319 if (repvalid && nonidempotent[nd->nd_procnum]) {
320 if ((nd->nd_flag & ND_NFSV3) == 0 &&
321 nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) {
322 rp->rc_status = nd->nd_repstat;
323 rp->rc_flag |= RC_REPSTATUS;
325 if (rp->rc_flag & RC_REPMBUF) {
326 m_freem(rp->rc_reply);
328 rp->rc_flag &= ~RC_REPMBUF;
330 rp->rc_reply = m_copym(repmbuf, 0,
332 rp->rc_flag |= RC_REPMBUF;
335 rp->rc_flag &= ~RC_LOCKED;
336 if (rp->rc_flag & RC_WANTED) {
337 rp->rc_flag &= ~RC_WANTED;
343 lwkt_reltoken(&srvcache_token);
344 NFS_DPF(RC, ("L%03x", nd->nd_retxid & 0xfff));
348 * Clean out the cache. Called when the last nfsd terminates.
351 nfsrv_cleancache(void)
353 struct nfsrvcache *rp;
355 lwkt_gettoken(&srvcache_token);
356 while ((rp = TAILQ_FIRST(&nfsrvlruhead)) != NULL) {
357 if (rp->rc_flag & RC_LOCKED) {
358 rp->rc_flag |= RC_WANTED;
359 tsleep((caddr_t)rp, 0, "nfsrc", 0);
362 LIST_REMOVE(rp, rc_hash);
363 TAILQ_REMOVE(&nfsrvlruhead, rp, rc_lru);
364 if (rp->rc_flag & RC_REPMBUF) {
365 m_freem(rp->rc_reply);
367 rp->rc_flag &= ~RC_REPMBUF;
369 if (rp->rc_flag & RC_NAM) {
370 kfree(rp->rc_nam, M_SONAME);
372 rp->rc_flag &= ~RC_NAM;
377 lwkt_reltoken(&srvcache_token);
380 #endif /* NFS_NOSERVER */