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 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * @(#)nfs_srvcache.c 8.3 (Berkeley) 3/30/95
33 * $FreeBSD: src/sys/nfs/nfs_srvcache.c,v 1.21 2000/02/13 03:32:06 peter Exp $
37 * Reference: Chet Juszczak, "Improving the Performance and Correctness
38 * of an NFS Server", in Proc. Winter 1989 USENIX Conference,
39 * pages 53-63. San Diego, February 1989.
41 #include <sys/param.h>
42 #include <sys/malloc.h>
43 #include <sys/mount.h>
44 #include <sys/systm.h>
46 #include <sys/socket.h>
47 #include <sys/socketvar.h> /* for dup_sockaddr */
49 #include <netinet/in.h>
53 #include "nfsrvcache.h"
56 static long numnfsrvcache
;
57 static long desirednfsrvcache
;
59 #define NFSRCHASH(xid) \
60 (&nfsrvhashtbl[((xid) + ((xid) >> 24)) & nfsrvhash])
61 static LIST_HEAD(nfsrvhash
, nfsrvcache
) *nfsrvhashtbl
;
62 static TAILQ_HEAD(nfsrvlru
, nfsrvcache
) nfsrvlruhead
;
63 static u_long nfsrvhash
;
68 #define NETFAMILY(rp) \
69 (((rp)->rc_flag & RC_INETADDR) ? AF_INET : AF_ISO)
71 struct lwkt_token srvcache_token
= LWKT_TOKEN_INITIALIZER(srvcache_token
);
74 * Static array that defines which nfs rpc's are nonidempotent
76 static int nonidempotent
[NFS_NPROCS
] = {
105 /* True iff the rpc reply is an nfs status ONLY! */
106 static int nfsv2_repstat
[NFS_NPROCS
] = {
128 * Size the NFS server's duplicate request cache at 1/2 the nmbclusters,
129 * within a (64, 2048) range. This is to prevent all mbuf clusters being
130 * tied up in the NFS dupreq cache for small values of nmbclusters.
133 nfsrvcache_size_change(void)
135 desirednfsrvcache
= nmbclusters
/ 2;
136 desirednfsrvcache
= MIN(desirednfsrvcache
, NFSRVCACHE_MAX_SIZE
);
137 desirednfsrvcache
= MAX(desirednfsrvcache
, NFSRVCACHE_MIN_SIZE
);
141 * Initialize the server request cache list
144 nfsrv_initcache(void)
146 nfsrvcache_size_change();
147 nfsrvhashtbl
= hashinit(desirednfsrvcache
, M_NFSD
, &nfsrvhash
);
148 TAILQ_INIT(&nfsrvlruhead
);
152 * Look for the request in the cache
154 * return action and optionally reply
156 * insert it in the cache
158 * The rules are as follows:
159 * - if in progress, return DROP request
160 * - if completed within DELAY of the current time, return DROP it
161 * - if completed a longer time ago return REPLY if the reply was cached or
163 * Update/add new request at end of lru list
166 nfsrv_getcache(struct nfsrv_descript
*nd
, struct nfssvc_sock
*slp
,
169 struct nfsrvcache
*rp
;
171 struct sockaddr_in
*saddr
;
176 * Don't cache recent requests for reliable transport protocols.
177 * (Maybe we should for the case of a reconnect, but..)
182 lwkt_gettoken(&srvcache_token
);
184 for (rp
= NFSRCHASH(nd
->nd_retxid
)->lh_first
; rp
!= NULL
;
185 rp
= rp
->rc_hash
.le_next
) {
186 if (nd
->nd_retxid
== rp
->rc_xid
&& nd
->nd_procnum
== rp
->rc_proc
&&
187 netaddr_match(NETFAMILY(rp
), &rp
->rc_haddr
, nd
->nd_nam
)) {
188 NFS_DPF(RC
, ("H%03x", rp
->rc_xid
& 0xfff));
189 if ((rp
->rc_flag
& RC_LOCKED
) != 0) {
190 rp
->rc_flag
|= RC_WANTED
;
191 tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
194 rp
->rc_flag
|= RC_LOCKED
;
195 /* If not at end of LRU chain, move it there */
196 if (TAILQ_NEXT(rp
, rc_lru
) != NULL
) {
197 TAILQ_REMOVE(&nfsrvlruhead
, rp
, rc_lru
);
198 TAILQ_INSERT_TAIL(&nfsrvlruhead
, rp
, rc_lru
);
200 if (rp
->rc_state
== RC_UNUSED
)
201 panic("nfsrv cache");
202 if (rp
->rc_state
== RC_INPROG
) {
203 nfsstats
.srvcache_inproghits
++;
205 } else if (rp
->rc_flag
& RC_REPSTATUS
) {
206 nfsstats
.srvcache_nonidemdonehits
++;
207 nfs_rephead(0, nd
, slp
, rp
->rc_status
,
210 } else if (rp
->rc_flag
& RC_REPMBUF
) {
211 nfsstats
.srvcache_nonidemdonehits
++;
212 *repp
= m_copym(rp
->rc_reply
, 0, M_COPYALL
,
216 nfsstats
.srvcache_idemdonehits
++;
217 rp
->rc_state
= RC_INPROG
;
220 rp
->rc_flag
&= ~RC_LOCKED
;
221 if (rp
->rc_flag
& RC_WANTED
) {
222 rp
->rc_flag
&= ~RC_WANTED
;
225 lwkt_reltoken(&srvcache_token
);
230 nfsstats
.srvcache_misses
++;
231 NFS_DPF(RC
, ("M%03x", nd
->nd_retxid
& 0xfff));
232 if (numnfsrvcache
< desirednfsrvcache
) {
233 rp
= kmalloc((u_long
)sizeof *rp
, M_NFSD
, M_WAITOK
| M_ZERO
);
235 rp
->rc_flag
= RC_LOCKED
;
237 rp
= TAILQ_FIRST(&nfsrvlruhead
);
238 while ((rp
->rc_flag
& RC_LOCKED
) != 0) {
239 rp
->rc_flag
|= RC_WANTED
;
240 tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
241 rp
= TAILQ_FIRST(&nfsrvlruhead
);
243 rp
->rc_flag
|= RC_LOCKED
;
244 LIST_REMOVE(rp
, rc_hash
);
245 TAILQ_REMOVE(&nfsrvlruhead
, rp
, rc_lru
);
246 if (rp
->rc_flag
& RC_REPMBUF
) {
247 m_freem(rp
->rc_reply
);
249 rp
->rc_flag
&= ~RC_REPMBUF
;
251 if (rp
->rc_flag
& RC_NAM
) {
252 kfree(rp
->rc_nam
, M_SONAME
);
254 rp
->rc_flag
&= ~RC_NAM
;
257 TAILQ_INSERT_TAIL(&nfsrvlruhead
, rp
, rc_lru
);
259 rp
->rc_state
= RC_INPROG
;
260 rp
->rc_xid
= nd
->nd_retxid
;
261 saddr
= (struct sockaddr_in
*)nd
->nd_nam
;
262 switch (saddr
->sin_family
) {
264 rp
->rc_flag
|= RC_INETADDR
;
265 rp
->rc_inetaddr
= saddr
->sin_addr
.s_addr
;
269 rp
->rc_flag
|= RC_NAM
;
270 rp
->rc_nam
= dup_sockaddr(nd
->nd_nam
);
273 rp
->rc_proc
= nd
->nd_procnum
;
274 LIST_INSERT_HEAD(NFSRCHASH(nd
->nd_retxid
), rp
, rc_hash
);
275 rp
->rc_flag
&= ~RC_LOCKED
;
276 if (rp
->rc_flag
& RC_WANTED
) {
277 rp
->rc_flag
&= ~RC_WANTED
;
280 lwkt_reltoken(&srvcache_token
);
286 * Update a request cache entry after the rpc has been done
289 nfsrv_updatecache(struct nfsrv_descript
*nd
, int repvalid
, struct mbuf
*repmbuf
)
291 struct nfsrvcache
*rp
;
296 lwkt_gettoken(&srvcache_token
);
298 for (rp
= NFSRCHASH(nd
->nd_retxid
)->lh_first
; rp
!= NULL
;
299 rp
= rp
->rc_hash
.le_next
) {
300 if (nd
->nd_retxid
== rp
->rc_xid
&& nd
->nd_procnum
== rp
->rc_proc
&&
301 netaddr_match(NETFAMILY(rp
), &rp
->rc_haddr
, nd
->nd_nam
)) {
302 NFS_DPF(RC
, ("U%03x", rp
->rc_xid
& 0xfff));
303 if ((rp
->rc_flag
& RC_LOCKED
) != 0) {
304 rp
->rc_flag
|= RC_WANTED
;
305 tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
308 rp
->rc_flag
|= RC_LOCKED
;
309 if (rp
->rc_state
== RC_DONE
) {
311 * This can occur if the cache is too small.
312 * Retransmits of the same request aren't
313 * dropped so we may see the operation
314 * complete more then once.
316 if (rp
->rc_flag
& RC_REPMBUF
) {
317 m_freem(rp
->rc_reply
);
319 rp
->rc_flag
&= ~RC_REPMBUF
;
322 rp
->rc_state
= RC_DONE
;
325 * If we have a valid reply update status and save
326 * the reply for non-idempotent rpc's.
328 if (repvalid
&& nonidempotent
[nd
->nd_procnum
]) {
329 if ((nd
->nd_flag
& ND_NFSV3
) == 0 &&
330 nfsv2_repstat
[nfsv2_procid
[nd
->nd_procnum
]]) {
331 rp
->rc_status
= nd
->nd_repstat
;
332 rp
->rc_flag
|= RC_REPSTATUS
;
334 if (rp
->rc_flag
& RC_REPMBUF
) {
335 m_freem(rp
->rc_reply
);
337 rp
->rc_flag
&= ~RC_REPMBUF
;
339 rp
->rc_reply
= m_copym(repmbuf
, 0,
341 rp
->rc_flag
|= RC_REPMBUF
;
344 rp
->rc_flag
&= ~RC_LOCKED
;
345 if (rp
->rc_flag
& RC_WANTED
) {
346 rp
->rc_flag
&= ~RC_WANTED
;
352 lwkt_reltoken(&srvcache_token
);
353 NFS_DPF(RC
, ("L%03x", nd
->nd_retxid
& 0xfff));
357 * Clean out the cache. Called when the last nfsd terminates.
360 nfsrv_cleancache(void)
362 struct nfsrvcache
*rp
;
364 lwkt_gettoken(&srvcache_token
);
365 while ((rp
= TAILQ_FIRST(&nfsrvlruhead
)) != NULL
) {
366 if (rp
->rc_flag
& RC_LOCKED
) {
367 rp
->rc_flag
|= RC_WANTED
;
368 tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
371 LIST_REMOVE(rp
, rc_hash
);
372 TAILQ_REMOVE(&nfsrvlruhead
, rp
, rc_lru
);
373 if (rp
->rc_flag
& RC_REPMBUF
) {
374 m_freem(rp
->rc_reply
);
376 rp
->rc_flag
&= ~RC_REPMBUF
;
378 if (rp
->rc_flag
& RC_NAM
) {
379 kfree(rp
->rc_nam
, M_SONAME
);
381 rp
->rc_flag
&= ~RC_NAM
;
386 lwkt_reltoken(&srvcache_token
);
389 #endif /* NFS_NOSERVER */