gems-kernel/source/THIRDPARTY/xnu/bsd/nfs/nfs_srvcache.c
2024-06-03 11:29:39 -05:00

456 lines
13 KiB
C

/*
* Copyright (c) 2000-2010 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* This file contains Original Code and/or Modifications of Original Code
* as defined in and that are subject to the Apple Public Source License
* Version 2.0 (the 'License'). You may not use this file except in
* compliance with the License. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* Please obtain a copy of the License at
* http://www.opensource.apple.com/apsl/ and read it before using this file.
*
* The Original Code and all software distributed under the License are
* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
* Please see the License for the specific language governing rights and
* limitations under the License.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rick Macklem at The University of Guelph.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)nfs_srvcache.c 8.3 (Berkeley) 3/30/95
* FreeBSD-Id: nfs_srvcache.c,v 1.15 1997/10/12 20:25:46 phk Exp $
*/
#include <nfs/nfs_conf.h>
#if CONFIG_NFS_SERVER
/*
* Reference: Chet Juszczak, "Improving the Performance and Correctness
* of an NFS Server", in Proc. Winter 1989 USENIX Conference,
* pages 53-63. San Diego, February 1989.
*/
#include <sys/param.h>
#include <sys/vnode.h>
#include <sys/mount_internal.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/kpi_mbuf.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <libkern/OSAtomic.h>
#include <netinet/in.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfsrvcache.h>
extern int nfsv2_procid[NFS_NPROCS];
static int nfsrv_reqcache_count;
int nfsrv_reqcache_size = NFSRVCACHESIZ;
#define NFSRCHASH(xid) \
(&nfsrv_reqcache_hashtbl[((xid) + ((xid) >> 24)) & nfsrv_reqcache_hash])
static LIST_HEAD(nfsrv_reqcache_hash, nfsrvcache) * nfsrv_reqcache_hashtbl;
static TAILQ_HEAD(nfsrv_reqcache_lru, nfsrvcache) nfsrv_reqcache_lruhead;
static u_long nfsrv_reqcache_hash;
static LCK_GRP_DECLARE(nfsrv_reqcache_lck_grp, "nfsrv_reqcache");
static LCK_MTX_DECLARE(nfsrv_reqcache_mutex, &nfsrv_reqcache_lck_grp);
/*
* Static array that defines which nfs rpc's are nonidempotent
*/
static int nonidempotent[NFS_NPROCS] = {
FALSE,
FALSE,
TRUE,
FALSE,
FALSE,
FALSE,
FALSE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
TRUE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
};
/* True iff the rpc reply is an nfs status ONLY! */
static int nfsv2_repstat[NFS_NPROCS] = {
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
FALSE,
TRUE,
TRUE,
TRUE,
TRUE,
FALSE,
TRUE,
FALSE,
FALSE,
};
/*
* Initialize the server request cache list
*/
void
nfsrv_initcache(void)
{
if (nfsrv_reqcache_size <= 0) {
return;
}
lck_mtx_lock(&nfsrv_reqcache_mutex);
/* init nfs server request cache hash table */
nfsrv_reqcache_hashtbl = hashinit(nfsrv_reqcache_size, M_NFSD, &nfsrv_reqcache_hash);
TAILQ_INIT(&nfsrv_reqcache_lruhead);
lck_mtx_unlock(&nfsrv_reqcache_mutex);
}
/*
* This function compares two net addresses by family and returns TRUE
* if they are the same host.
* If there is any doubt, return FALSE.
* The AF_INET family is handled as a special case so that address mbufs
* don't need to be saved to store "struct in_addr", which is only 4 bytes.
* Ditto for AF_INET6 which is only 16 bytes.
*/
static int
netaddr_match(
int family,
union nethostaddr *haddr,
mbuf_t nam)
{
struct sockaddr_in *inetaddr;
struct sockaddr_in6 *inet6addr;
switch (family) {
case AF_INET:
inetaddr = mbuf_data(nam);
if ((inetaddr->sin_family == AF_INET) &&
(inetaddr->sin_addr.s_addr == haddr->had_inetaddr)) {
return 1;
}
break;
case AF_INET6:
inet6addr = mbuf_data(nam);
if ((inet6addr->sin6_family == AF_INET6) &&
!bcmp(&inet6addr->sin6_addr, &haddr->had_inet6addr, sizeof(inet6addr->sin6_addr))) {
return 1;
}
break;
}
return 0;
}
/*
* Look for the request in the cache
* If found then
* return action and optionally reply
* else
* insert it in the cache
*
* The rules are as follows:
* - if in progress, return DROP request
* - if completed within DELAY of the current time, return DROP it
* - if completed a longer time ago return REPLY if the reply was cached or
* return DOIT
* Update/add new request at end of lru list
*/
int
nfsrv_getcache(
struct nfsrv_descript *nd,
struct nfsrv_sock *slp,
mbuf_t *mrepp)
{
struct nfsrvcache *rp;
struct nfsm_chain nmrep;
struct sockaddr *saddr;
int ret, error;
/*
* Don't cache recent requests for reliable transport protocols.
* (Maybe we should for the case of a reconnect, but..)
*/
if (!nd->nd_nam2) {
return RC_DOIT;
}
lck_mtx_lock(&nfsrv_reqcache_mutex);
loop:
for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0;
rp = rp->rc_hash.le_next) {
if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
netaddr_match(rp->rc_family, &rp->rc_haddr, nd->nd_nam)) {
if ((rp->rc_flag & RC_LOCKED) != 0) {
rp->rc_flag |= RC_WANTED;
msleep(rp, &nfsrv_reqcache_mutex, PZERO - 1, "nfsrc", NULL);
goto loop;
}
rp->rc_flag |= RC_LOCKED;
/* If not at end of LRU chain, move it there */
if (rp->rc_lru.tqe_next) {
TAILQ_REMOVE(&nfsrv_reqcache_lruhead, rp, rc_lru);
TAILQ_INSERT_TAIL(&nfsrv_reqcache_lruhead, rp, rc_lru);
}
if (rp->rc_state == RC_UNUSED) {
panic("nfsrv cache");
}
if (rp->rc_state == RC_INPROG) {
OSAddAtomic64(1, &nfsrvstats.srvcache_inproghits);
ret = RC_DROPIT;
} else if (rp->rc_flag & RC_REPSTATUS) {
OSAddAtomic64(1, &nfsrvstats.srvcache_nonidemdonehits);
nd->nd_repstat = rp->rc_status;
error = nfsrv_rephead(nd, slp, &nmrep, 0);
if (error) {
printf("nfsrv cache: reply alloc failed for nonidem request hit\n");
ret = RC_DROPIT;
*mrepp = NULL;
} else {
ret = RC_REPLY;
*mrepp = nmrep.nmc_mhead;
}
} else if (rp->rc_flag & RC_REPMBUF) {
OSAddAtomic64(1, &nfsrvstats.srvcache_nonidemdonehits);
error = mbuf_copym(rp->rc_reply, 0, MBUF_COPYALL, MBUF_WAITOK, mrepp);
if (error) {
printf("nfsrv cache: reply copym failed for nonidem request hit\n");
ret = RC_DROPIT;
} else {
ret = RC_REPLY;
}
} else {
OSAddAtomic64(1, &nfsrvstats.srvcache_idemdonehits);
rp->rc_state = RC_INPROG;
ret = RC_DOIT;
}
rp->rc_flag &= ~RC_LOCKED;
if (rp->rc_flag & RC_WANTED) {
rp->rc_flag &= ~RC_WANTED;
wakeup(rp);
}
lck_mtx_unlock(&nfsrv_reqcache_mutex);
return ret;
}
}
OSAddAtomic64(1, &nfsrvstats.srvcache_misses);
if (nfsrv_reqcache_count < nfsrv_reqcache_size) {
/* try to allocate a new entry */
rp = kalloc_type(struct nfsrvcache, Z_WAITOK | Z_ZERO | Z_NOFAIL);
rp->rc_flag = RC_LOCKED;
nfsrv_reqcache_count++;
} else {
rp = NULL;
}
if (!rp) {
/* try to reuse the least recently used entry */
rp = nfsrv_reqcache_lruhead.tqh_first;
if (!rp) {
/* no entry to reuse? */
/* OK, we just won't be able to cache this request */
lck_mtx_unlock(&nfsrv_reqcache_mutex);
return RC_DOIT;
}
while ((rp->rc_flag & RC_LOCKED) != 0) {
rp->rc_flag |= RC_WANTED;
msleep(rp, &nfsrv_reqcache_mutex, PZERO - 1, "nfsrc", NULL);
rp = nfsrv_reqcache_lruhead.tqh_first;
}
rp->rc_flag |= RC_LOCKED;
LIST_REMOVE(rp, rc_hash);
TAILQ_REMOVE(&nfsrv_reqcache_lruhead, rp, rc_lru);
if (rp->rc_flag & RC_REPMBUF) {
mbuf_freem(rp->rc_reply);
}
if (rp->rc_flag & RC_NAM) {
mbuf_freem(rp->rc_nam);
}
rp->rc_flag &= (RC_LOCKED | RC_WANTED);
}
TAILQ_INSERT_TAIL(&nfsrv_reqcache_lruhead, rp, rc_lru);
rp->rc_state = RC_INPROG;
rp->rc_xid = nd->nd_retxid;
saddr = mbuf_data(nd->nd_nam);
rp->rc_family = saddr->sa_family;
switch (saddr->sa_family) {
case AF_INET:
rp->rc_flag |= RC_INETADDR;
rp->rc_inetaddr = ((struct sockaddr_in*)saddr)->sin_addr.s_addr;
break;
case AF_INET6:
rp->rc_flag |= RC_INETADDR;
rp->rc_inet6addr = ((struct sockaddr_in6*)saddr)->sin6_addr;
break;
default:
error = mbuf_copym(nd->nd_nam, 0, MBUF_COPYALL, MBUF_WAITOK, &rp->rc_nam);
if (error) {
printf("nfsrv cache: nam copym failed\n");
} else {
rp->rc_flag |= RC_NAM;
}
break;
}
;
rp->rc_proc = nd->nd_procnum;
LIST_INSERT_HEAD(NFSRCHASH(nd->nd_retxid), rp, rc_hash);
rp->rc_flag &= ~RC_LOCKED;
if (rp->rc_flag & RC_WANTED) {
rp->rc_flag &= ~RC_WANTED;
wakeup(rp);
}
lck_mtx_unlock(&nfsrv_reqcache_mutex);
return RC_DOIT;
}
/*
* Update a request cache entry after the rpc has been done
*/
void
nfsrv_updatecache(
struct nfsrv_descript *nd,
int repvalid,
mbuf_t repmbuf)
{
struct nfsrvcache *rp;
int error;
if (!nd->nd_nam2) {
return;
}
lck_mtx_lock(&nfsrv_reqcache_mutex);
loop:
for (rp = NFSRCHASH(nd->nd_retxid)->lh_first; rp != 0;
rp = rp->rc_hash.le_next) {
if (nd->nd_retxid == rp->rc_xid && nd->nd_procnum == rp->rc_proc &&
netaddr_match(rp->rc_family, &rp->rc_haddr, nd->nd_nam)) {
if ((rp->rc_flag & RC_LOCKED) != 0) {
rp->rc_flag |= RC_WANTED;
msleep(rp, &nfsrv_reqcache_mutex, PZERO - 1, "nfsrc", NULL);
goto loop;
}
rp->rc_flag |= RC_LOCKED;
if (rp->rc_state == RC_DONE) {
/*
* This can occur if the cache is too small.
* Retransmits of the same request aren't
* dropped so we may see the operation
* complete more then once.
*/
if (rp->rc_flag & RC_REPMBUF) {
mbuf_freem(rp->rc_reply);
rp->rc_flag &= ~RC_REPMBUF;
}
}
rp->rc_state = RC_DONE;
/*
* If we have a valid reply update status and save
* the reply for non-idempotent rpc's.
*/
if (repvalid && nonidempotent[nd->nd_procnum]) {
if ((nd->nd_vers == NFS_VER2) &&
nfsv2_repstat[nfsv2_procid[nd->nd_procnum]]) {
rp->rc_status = nd->nd_repstat;
rp->rc_flag |= RC_REPSTATUS;
} else {
error = mbuf_copym(repmbuf, 0, MBUF_COPYALL, MBUF_WAITOK, &rp->rc_reply);
if (!error) {
rp->rc_flag |= RC_REPMBUF;
}
}
}
rp->rc_flag &= ~RC_LOCKED;
if (rp->rc_flag & RC_WANTED) {
rp->rc_flag &= ~RC_WANTED;
wakeup(rp);
}
lck_mtx_unlock(&nfsrv_reqcache_mutex);
return;
}
}
lck_mtx_unlock(&nfsrv_reqcache_mutex);
}
/*
* Clean out the cache. Called when the last nfsd terminates.
*/
void
nfsrv_cleancache(void)
{
struct nfsrvcache *rp, *nextrp;
lck_mtx_lock(&nfsrv_reqcache_mutex);
TAILQ_FOREACH_SAFE(rp, &nfsrv_reqcache_lruhead, rc_lru, nextrp) {
kfree_type(struct nfsrvcache, rp);
}
hashdestroy(nfsrv_reqcache_hashtbl, M_NFSD, nfsrv_reqcache_hash);
nfsrv_reqcache_hash = 0;
nfsrv_reqcache_count = 0;
TAILQ_INIT(&nfsrv_reqcache_lruhead);
lck_mtx_unlock(&nfsrv_reqcache_mutex);
}
#endif /* CONFIG_NFS_SERVER */