NetBSD/sys/nfs/nfs_iod.c

445 lines
12 KiB
C

/* $NetBSD: nfs_iod.c,v 1.4 2009/12/31 19:38:16 christos Exp $ */
/*
* 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. 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_syscalls.c 8.5 (Berkeley) 3/30/95
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: nfs_iod.c,v 1.4 2009/12/31 19:38:16 christos Exp $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/file.h>
#include <sys/stat.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/uio.h>
#include <sys/malloc.h>
#include <sys/kmem.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/signalvar.h>
#include <sys/domain.h>
#include <sys/protosw.h>
#include <sys/namei.h>
#include <sys/syslog.h>
#include <sys/filedesc.h>
#include <sys/kthread.h>
#include <sys/kauth.h>
#include <sys/syscallargs.h>
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <nfs/xdr_subs.h>
#include <nfs/rpcv2.h>
#include <nfs/nfsproto.h>
#include <nfs/nfs.h>
#include <nfs/nfsm_subs.h>
#include <nfs/nfsrvcache.h>
#include <nfs/nfsmount.h>
#include <nfs/nfsnode.h>
#include <nfs/nfsrtt.h>
#include <nfs/nfs_var.h>
extern int nuidhash_max;
/*
* locking order:
* nfs_iodlist_lock -> nid_lock -> nm_lock
*/
kmutex_t nfs_iodlist_lock;
struct nfs_iodlist nfs_iodlist_idle;
struct nfs_iodlist nfs_iodlist_all;
int nfs_niothreads = -1; /* == "0, and has never been set" */
int nfs_defect = 0;
/*
* Asynchronous I/O threads for client nfs.
* They do read-ahead and write-behind operations on the block I/O cache.
* Never returns unless it fails or gets killed.
*/
static void
nfssvc_iod(void *arg)
{
struct buf *bp;
struct nfs_iod *myiod;
struct nfsmount *nmp;
myiod = kmem_alloc(sizeof(*myiod), KM_SLEEP);
mutex_init(&myiod->nid_lock, MUTEX_DEFAULT, IPL_NONE);
cv_init(&myiod->nid_cv, "nfsiod");
myiod->nid_exiting = false;
myiod->nid_mount = NULL;
mutex_enter(&nfs_iodlist_lock);
LIST_INSERT_HEAD(&nfs_iodlist_all, myiod, nid_all);
mutex_exit(&nfs_iodlist_lock);
for (;;) {
mutex_enter(&nfs_iodlist_lock);
LIST_INSERT_HEAD(&nfs_iodlist_idle, myiod, nid_idle);
mutex_exit(&nfs_iodlist_lock);
mutex_enter(&myiod->nid_lock);
while (/*CONSTCOND*/ true) {
nmp = myiod->nid_mount;
if (nmp) {
myiod->nid_mount = NULL;
break;
}
if (__predict_false(myiod->nid_exiting)) {
/*
* drop nid_lock to preserve locking order.
*/
mutex_exit(&myiod->nid_lock);
mutex_enter(&nfs_iodlist_lock);
mutex_enter(&myiod->nid_lock);
/*
* recheck nid_mount because nfs_asyncio can
* pick us in the meantime as we are still on
* nfs_iodlist_lock.
*/
if (myiod->nid_mount != NULL) {
mutex_exit(&nfs_iodlist_lock);
continue;
}
LIST_REMOVE(myiod, nid_idle);
mutex_exit(&nfs_iodlist_lock);
goto quit;
}
cv_wait(&myiod->nid_cv, &myiod->nid_lock);
}
mutex_exit(&myiod->nid_lock);
mutex_enter(&nmp->nm_lock);
while ((bp = TAILQ_FIRST(&nmp->nm_bufq)) != NULL) {
/* Take one off the front of the list */
TAILQ_REMOVE(&nmp->nm_bufq, bp, b_freelist);
nmp->nm_bufqlen--;
if (nmp->nm_bufqlen < 2 * nmp->nm_bufqiods) {
cv_broadcast(&nmp->nm_aiocv);
}
mutex_exit(&nmp->nm_lock);
KERNEL_LOCK(1, curlwp);
(void)nfs_doio(bp);
KERNEL_UNLOCK_LAST(curlwp);
mutex_enter(&nmp->nm_lock);
/*
* If there are more than one iod on this mount,
* then defect so that the iods can be shared out
* fairly between the mounts
*/
if (nfs_defect && nmp->nm_bufqiods > 1) {
break;
}
}
KASSERT(nmp->nm_bufqiods > 0);
nmp->nm_bufqiods--;
mutex_exit(&nmp->nm_lock);
}
quit:
KASSERT(myiod->nid_mount == NULL);
mutex_exit(&myiod->nid_lock);
cv_destroy(&myiod->nid_cv);
mutex_destroy(&myiod->nid_lock);
kmem_free(myiod, sizeof(*myiod));
kthread_exit(0);
}
void
nfs_iodinit(void)
{
mutex_init(&nfs_iodlist_lock, MUTEX_DEFAULT, IPL_NONE);
LIST_INIT(&nfs_iodlist_all);
LIST_INIT(&nfs_iodlist_idle);
}
void
nfs_iodfini(void)
{
int error;
error = nfs_set_niothreads(0);
KASSERT(error == 0);
mutex_destroy(&nfs_iodlist_lock);
}
int
nfs_set_niothreads(int newval)
{
struct nfs_iod *nid;
int error = 0;
int hold_count;
KERNEL_UNLOCK_ALL(curlwp, &hold_count);
mutex_enter(&nfs_iodlist_lock);
/* clamp to sane range */
nfs_niothreads = max(0, min(newval, NFS_MAXASYNCDAEMON));
while (nfs_numasync != nfs_niothreads && error == 0) {
while (nfs_numasync < nfs_niothreads) {
/*
* kthread_create can wait for pagedaemon and
* pagedaemon can wait for nfsiod which needs to acquire
* nfs_iodlist_lock.
*/
mutex_exit(&nfs_iodlist_lock);
error = kthread_create(PRI_NONE, KTHREAD_MPSAFE, NULL,
nfssvc_iod, NULL, NULL, "nfsio");
mutex_enter(&nfs_iodlist_lock);
if (error) {
/* give up */
nfs_niothreads = nfs_numasync;
break;
}
nfs_numasync++;
}
while (nfs_numasync > nfs_niothreads) {
nid = LIST_FIRST(&nfs_iodlist_all);
if (nid == NULL) {
/* iod has not started yet. */
kpause("nfsiorm", false, hz, &nfs_iodlist_lock);
continue;
}
LIST_REMOVE(nid, nid_all);
mutex_enter(&nid->nid_lock);
KASSERT(!nid->nid_exiting);
nid->nid_exiting = true;
cv_signal(&nid->nid_cv);
mutex_exit(&nid->nid_lock);
nfs_numasync--;
}
}
mutex_exit(&nfs_iodlist_lock);
KERNEL_LOCK(hold_count, curlwp);
return error;
}
/*
* Get an authorization string for the uid by having the mount_nfs sitting
* on this mount point porpous out of the kernel and do it.
*/
int
nfs_getauth(struct nfsmount *nmp, struct nfsreq *rep, kauth_cred_t cred, char **auth_str, int *auth_len, char *verf_str, int *verf_len, NFSKERBKEY_T key)
/* key: return session key */
{
int error = 0;
while ((nmp->nm_iflag & NFSMNT_WAITAUTH) == 0) {
nmp->nm_iflag |= NFSMNT_WANTAUTH;
(void) tsleep((void *)&nmp->nm_authtype, PSOCK,
"nfsauth1", 2 * hz);
error = nfs_sigintr(nmp, rep, rep->r_lwp);
if (error) {
nmp->nm_iflag &= ~NFSMNT_WANTAUTH;
return (error);
}
}
nmp->nm_iflag &= ~(NFSMNT_WAITAUTH | NFSMNT_WANTAUTH);
nmp->nm_authstr = *auth_str = (char *)malloc(RPCAUTH_MAXSIZ, M_TEMP, M_WAITOK);
nmp->nm_authlen = RPCAUTH_MAXSIZ;
nmp->nm_verfstr = verf_str;
nmp->nm_verflen = *verf_len;
nmp->nm_authuid = kauth_cred_geteuid(cred);
wakeup((void *)&nmp->nm_authstr);
/*
* And wait for mount_nfs to do its stuff.
*/
while ((nmp->nm_iflag & NFSMNT_HASAUTH) == 0 && error == 0) {
(void) tsleep((void *)&nmp->nm_authlen, PSOCK,
"nfsauth2", 2 * hz);
error = nfs_sigintr(nmp, rep, rep->r_lwp);
}
if (nmp->nm_iflag & NFSMNT_AUTHERR) {
nmp->nm_iflag &= ~NFSMNT_AUTHERR;
error = EAUTH;
}
if (error)
free((void *)*auth_str, M_TEMP);
else {
*auth_len = nmp->nm_authlen;
*verf_len = nmp->nm_verflen;
memcpy(key, nmp->nm_key, sizeof (NFSKERBKEY_T));
}
nmp->nm_iflag &= ~NFSMNT_HASAUTH;
nmp->nm_iflag |= NFSMNT_WAITAUTH;
if (nmp->nm_iflag & NFSMNT_WANTAUTH) {
nmp->nm_iflag &= ~NFSMNT_WANTAUTH;
wakeup((void *)&nmp->nm_authtype);
}
return (error);
}
/*
* Get a nickname authenticator and verifier.
*/
int
nfs_getnickauth(struct nfsmount *nmp, kauth_cred_t cred, char **auth_str,
int *auth_len, char *verf_str, int verf_len)
{
struct timeval ktvin, ktvout, tv;
struct nfsuid *nuidp;
u_int32_t *nickp, *verfp;
memset(&ktvout, 0, sizeof ktvout); /* XXX gcc */
#ifdef DIAGNOSTIC
if (verf_len < (4 * NFSX_UNSIGNED))
panic("nfs_getnickauth verf too small");
#endif
LIST_FOREACH(nuidp, NMUIDHASH(nmp, kauth_cred_geteuid(cred)), nu_hash) {
if (kauth_cred_geteuid(nuidp->nu_cr) == kauth_cred_geteuid(cred))
break;
}
if (!nuidp || nuidp->nu_expire < time_second)
return (EACCES);
/*
* Move to the end of the lru list (end of lru == most recently used).
*/
TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp, nu_lru);
TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp, nu_lru);
nickp = (u_int32_t *)malloc(2 * NFSX_UNSIGNED, M_TEMP, M_WAITOK);
*nickp++ = txdr_unsigned(RPCAKN_NICKNAME);
*nickp = txdr_unsigned(nuidp->nu_nickname);
*auth_str = (char *)nickp;
*auth_len = 2 * NFSX_UNSIGNED;
/*
* Now we must encrypt the verifier and package it up.
*/
verfp = (u_int32_t *)verf_str;
*verfp++ = txdr_unsigned(RPCAKN_NICKNAME);
getmicrotime(&tv);
if (tv.tv_sec > nuidp->nu_timestamp.tv_sec ||
(tv.tv_sec == nuidp->nu_timestamp.tv_sec &&
tv.tv_usec > nuidp->nu_timestamp.tv_usec))
nuidp->nu_timestamp = tv;
else
nuidp->nu_timestamp.tv_usec++;
ktvin.tv_sec = txdr_unsigned(nuidp->nu_timestamp.tv_sec);
ktvin.tv_usec = txdr_unsigned(nuidp->nu_timestamp.tv_usec);
/*
* Now encrypt the timestamp verifier in ecb mode using the session
* key.
*/
#ifdef NFSKERB
XXX
#endif
*verfp++ = ktvout.tv_sec;
*verfp++ = ktvout.tv_usec;
*verfp = 0;
return (0);
}
/*
* Save the current nickname in a hash list entry on the mount point.
*/
int
nfs_savenickauth(struct nfsmount *nmp, kauth_cred_t cred, int len, NFSKERBKEY_T key, struct mbuf **mdp, char **dposp, struct mbuf *mrep)
{
struct nfsuid *nuidp;
u_int32_t *tl;
int32_t t1;
struct mbuf *md = *mdp;
struct timeval ktvin, ktvout;
u_int32_t nick;
char *dpos = *dposp, *cp2;
int deltasec, error = 0;
memset(&ktvout, 0, sizeof ktvout); /* XXX gcc */
if (len == (3 * NFSX_UNSIGNED)) {
nfsm_dissect(tl, u_int32_t *, 3 * NFSX_UNSIGNED);
ktvin.tv_sec = *tl++;
ktvin.tv_usec = *tl++;
nick = fxdr_unsigned(u_int32_t, *tl);
/*
* Decrypt the timestamp in ecb mode.
*/
#ifdef NFSKERB
XXX
#endif
ktvout.tv_sec = fxdr_unsigned(long, ktvout.tv_sec);
ktvout.tv_usec = fxdr_unsigned(long, ktvout.tv_usec);
deltasec = time_second - ktvout.tv_sec;
if (deltasec < 0)
deltasec = -deltasec;
/*
* If ok, add it to the hash list for the mount point.
*/
if (deltasec <= NFS_KERBCLOCKSKEW) {
if (nmp->nm_numuids < nuidhash_max) {
nmp->nm_numuids++;
nuidp = kmem_alloc(sizeof(*nuidp), KM_SLEEP);
} else {
nuidp = TAILQ_FIRST(&nmp->nm_uidlruhead);
LIST_REMOVE(nuidp, nu_hash);
TAILQ_REMOVE(&nmp->nm_uidlruhead, nuidp,
nu_lru);
}
nuidp->nu_flag = 0;
kauth_cred_seteuid(nuidp->nu_cr, kauth_cred_geteuid(cred));
nuidp->nu_expire = time_second + NFS_KERBTTL;
nuidp->nu_timestamp = ktvout;
nuidp->nu_nickname = nick;
memcpy(nuidp->nu_key, key, sizeof (NFSKERBKEY_T));
TAILQ_INSERT_TAIL(&nmp->nm_uidlruhead, nuidp,
nu_lru);
LIST_INSERT_HEAD(NMUIDHASH(nmp, kauth_cred_geteuid(cred)),
nuidp, nu_hash);
}
} else
nfsm_adv(nfsm_rndup(len));
nfsmout:
*mdp = md;
*dposp = dpos;
return (error);
}