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)
77 * Static array that defines which nfs rpc's are nonidempotent
79 static int nonidempotent
[NFS_NPROCS
] = {
108 /* True iff the rpc reply is an nfs status ONLY! */
109 static int nfsv2_repstat
[NFS_NPROCS
] = {
131 * Initialize the server request cache list
134 nfsrv_initcache(void)
137 nfsrvhashtbl
= hashinit(desirednfsrvcache
, M_NFSD
, &nfsrvhash
);
138 TAILQ_INIT(&nfsrvlruhead
);
142 * Look for the request in the cache
144 * return action and optionally reply
146 * insert it in the cache
148 * The rules are as follows:
149 * - if in progress, return DROP request
150 * - if completed within DELAY of the current time, return DROP it
151 * - if completed a longer time ago return REPLY if the reply was cached or
153 * Update/add new request at end of lru list
156 nfsrv_getcache(struct nfsrv_descript
*nd
, struct nfssvc_sock
*slp
,
159 struct nfsrvcache
*rp
;
161 struct sockaddr_in
*saddr
;
166 * Don't cache recent requests for reliable transport protocols.
167 * (Maybe we should for the case of a reconnect, but..)
172 for (rp
= NFSRCHASH(nd
->nd_retxid
)->lh_first
; rp
!= 0;
173 rp
= rp
->rc_hash
.le_next
) {
174 if (nd
->nd_retxid
== rp
->rc_xid
&& nd
->nd_procnum
== rp
->rc_proc
&&
175 netaddr_match(NETFAMILY(rp
), &rp
->rc_haddr
, nd
->nd_nam
)) {
176 NFS_DPF(RC
, ("H%03x", rp
->rc_xid
& 0xfff));
177 if ((rp
->rc_flag
& RC_LOCKED
) != 0) {
178 rp
->rc_flag
|= RC_WANTED
;
179 (void) tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
182 rp
->rc_flag
|= RC_LOCKED
;
183 /* If not at end of LRU chain, move it there */
184 if (TAILQ_NEXT(rp
, rc_lru
) != NULL
) {
185 TAILQ_REMOVE(&nfsrvlruhead
, rp
, rc_lru
);
186 TAILQ_INSERT_TAIL(&nfsrvlruhead
, rp
, rc_lru
);
188 if (rp
->rc_state
== RC_UNUSED
)
189 panic("nfsrv cache");
190 if (rp
->rc_state
== RC_INPROG
) {
191 nfsstats
.srvcache_inproghits
++;
193 } else if (rp
->rc_flag
& RC_REPSTATUS
) {
194 nfsstats
.srvcache_nonidemdonehits
++;
195 nfs_rephead(0, nd
, slp
, rp
->rc_status
,
198 } else if (rp
->rc_flag
& RC_REPMBUF
) {
199 nfsstats
.srvcache_nonidemdonehits
++;
200 *repp
= m_copym(rp
->rc_reply
, 0, M_COPYALL
,
204 nfsstats
.srvcache_idemdonehits
++;
205 rp
->rc_state
= RC_INPROG
;
208 rp
->rc_flag
&= ~RC_LOCKED
;
209 if (rp
->rc_flag
& RC_WANTED
) {
210 rp
->rc_flag
&= ~RC_WANTED
;
216 nfsstats
.srvcache_misses
++;
217 NFS_DPF(RC
, ("M%03x", nd
->nd_retxid
& 0xfff));
218 if (numnfsrvcache
< desirednfsrvcache
) {
219 rp
= (struct nfsrvcache
*)kmalloc((u_long
)sizeof *rp
,
220 M_NFSD
, M_WAITOK
| M_ZERO
);
222 rp
->rc_flag
= RC_LOCKED
;
224 rp
= TAILQ_FIRST(&nfsrvlruhead
);
225 while ((rp
->rc_flag
& RC_LOCKED
) != 0) {
226 rp
->rc_flag
|= RC_WANTED
;
227 (void) tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
228 rp
= TAILQ_FIRST(&nfsrvlruhead
);
230 rp
->rc_flag
|= RC_LOCKED
;
231 LIST_REMOVE(rp
, rc_hash
);
232 TAILQ_REMOVE(&nfsrvlruhead
, rp
, rc_lru
);
233 if (rp
->rc_flag
& RC_REPMBUF
)
234 m_freem(rp
->rc_reply
);
235 if (rp
->rc_flag
& RC_NAM
)
236 FREE(rp
->rc_nam
, M_SONAME
);
237 rp
->rc_flag
&= (RC_LOCKED
| RC_WANTED
);
239 TAILQ_INSERT_TAIL(&nfsrvlruhead
, rp
, rc_lru
);
240 rp
->rc_state
= RC_INPROG
;
241 rp
->rc_xid
= nd
->nd_retxid
;
242 saddr
= (struct sockaddr_in
*)nd
->nd_nam
;
243 switch (saddr
->sin_family
) {
245 rp
->rc_flag
|= RC_INETADDR
;
246 rp
->rc_inetaddr
= saddr
->sin_addr
.s_addr
;
250 rp
->rc_flag
|= RC_NAM
;
251 rp
->rc_nam
= dup_sockaddr(nd
->nd_nam
);
254 rp
->rc_proc
= nd
->nd_procnum
;
255 LIST_INSERT_HEAD(NFSRCHASH(nd
->nd_retxid
), rp
, rc_hash
);
256 rp
->rc_flag
&= ~RC_LOCKED
;
257 if (rp
->rc_flag
& RC_WANTED
) {
258 rp
->rc_flag
&= ~RC_WANTED
;
265 * Update a request cache entry after the rpc has been done
268 nfsrv_updatecache(struct nfsrv_descript
*nd
, int repvalid
, struct mbuf
*repmbuf
)
270 struct nfsrvcache
*rp
;
275 for (rp
= NFSRCHASH(nd
->nd_retxid
)->lh_first
; rp
!= 0;
276 rp
= rp
->rc_hash
.le_next
) {
277 if (nd
->nd_retxid
== rp
->rc_xid
&& nd
->nd_procnum
== rp
->rc_proc
&&
278 netaddr_match(NETFAMILY(rp
), &rp
->rc_haddr
, nd
->nd_nam
)) {
279 NFS_DPF(RC
, ("U%03x", rp
->rc_xid
& 0xfff));
280 if ((rp
->rc_flag
& RC_LOCKED
) != 0) {
281 rp
->rc_flag
|= RC_WANTED
;
282 (void) tsleep((caddr_t
)rp
, 0, "nfsrc", 0);
285 rp
->rc_flag
|= RC_LOCKED
;
286 if (rp
->rc_state
== RC_DONE
) {
288 * This can occur if the cache is too small.
289 * Retransmits of the same request aren't
290 * dropped so we may see the operation
291 * complete more then once.
293 if (rp
->rc_flag
& RC_REPMBUF
) {
294 m_freem(rp
->rc_reply
);
295 rp
->rc_flag
&= ~RC_REPMBUF
;
298 rp
->rc_state
= RC_DONE
;
300 * If we have a valid reply update status and save
301 * the reply for non-idempotent rpc's.
303 if (repvalid
&& nonidempotent
[nd
->nd_procnum
]) {
304 if ((nd
->nd_flag
& ND_NFSV3
) == 0 &&
305 nfsv2_repstat
[nfsv2_procid
[nd
->nd_procnum
]]) {
306 rp
->rc_status
= nd
->nd_repstat
;
307 rp
->rc_flag
|= RC_REPSTATUS
;
309 rp
->rc_reply
= m_copym(repmbuf
,
310 0, M_COPYALL
, MB_WAIT
);
311 rp
->rc_flag
|= RC_REPMBUF
;
314 rp
->rc_flag
&= ~RC_LOCKED
;
315 if (rp
->rc_flag
& RC_WANTED
) {
316 rp
->rc_flag
&= ~RC_WANTED
;
322 NFS_DPF(RC
, ("L%03x", nd
->nd_retxid
& 0xfff));
326 * Clean out the cache. Called when the last nfsd terminates.
329 nfsrv_cleancache(void)
331 struct nfsrvcache
*rp
, *nextrp
;
333 TAILQ_FOREACH_MUTABLE(rp
, &nfsrvlruhead
, rc_lru
, nextrp
) {
334 LIST_REMOVE(rp
, rc_hash
);
335 TAILQ_REMOVE(&nfsrvlruhead
, rp
, rc_lru
);
336 if (rp
->rc_flag
& RC_REPMBUF
)
337 m_freem(rp
->rc_reply
);
338 if (rp
->rc_flag
& RC_NAM
)
339 kfree(rp
->rc_nam
, M_SONAME
);
345 #endif /* NFS_NOSERVER */