freebsd-nq/usr.sbin/rpc.lockd/lockd_lock.c
Alfred Perlstein bad584e319 Implement partial-file NFS lock testing.
Submitted by: "Andrew P. Lentvorski" <andrewl@io.com>
2001-10-14 18:36:35 +00:00

820 lines
22 KiB
C

/* $NetBSD: lockd_lock.c,v 1.5 2000/11/21 03:47:41 enami Exp $ */
/* $FreeBSD$ */
/*
* Copyright (c) 2000 Manuel Bouyer.
*
* 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.
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <syslog.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <rpc/rpc.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/wait.h>
#include <rpcsvc/sm_inter.h>
#include <rpcsvc/nlm_prot.h>
#include "lockd_lock.h"
#include "lockd.h"
/*
* A set of utilities for managing file locking
*
* XXX: All locks are in a linked list, a better structure should be used
* to improve search/access effeciency.
*/
LIST_HEAD(lcklst_head, file_lock);
struct lcklst_head lcklst_head = LIST_HEAD_INITIALIZER(lcklst_head);
/* struct describing a lock */
struct file_lock {
LIST_ENTRY(file_lock) lcklst;
fhandle_t filehandle; /* NFS filehandle */
struct sockaddr *addr;
struct nlm4_holder client; /* lock holder */
netobj client_cookie; /* cookie sent by the client */
char client_name[128];
int nsm_status; /* status from the remote lock manager */
int status; /* lock status, see below */
int flags; /* lock flags, see lockd_lock.h */
pid_t locker; /* pid of the child process trying to get the lock */
int fd; /* file descriptor for this lock */
};
/* lock status */
#define LKST_LOCKED 1 /* lock is locked */
/* XXX: Is this flag file specific or lock specific? */
#define LKST_WAITING 2 /* file is already locked by another host */
#define LKST_PROCESSING 3 /* child is trying to aquire the lock */
#define LKST_DYING 4 /* must dies when we get news from the child */
void lfree __P((struct file_lock *));
enum nlm_stats do_lock __P((struct file_lock *, int));
enum nlm_stats do_unlock __P((struct file_lock *));
void send_granted __P((struct file_lock *, int));
void siglock __P((void));
void sigunlock __P((void));
int regions_overlap __P((u_int64_t start1, u_int64_t len1, u_int64_t start2,
u_int64_t len2));
/* list of hosts we monitor */
LIST_HEAD(hostlst_head, host);
struct hostlst_head hostlst_head = LIST_HEAD_INITIALIZER(hostlst_head);
/* struct describing a lock */
struct host {
LIST_ENTRY(host) hostlst;
char name[SM_MAXSTRLEN];
int refcnt;
};
void do_mon __P((char *));
/*
* regions_overlap(): This function examines the two provided regions for overlap.
* It is non-trivial because start+len *CAN* overflow a 64-bit unsigned integer
* and NFS semantics are unspecified on this account.
*/
int
regions_overlap(start1, len1, start2, len2)
u_int64_t start1, len1, start2, len2;
{
int result;
/* XXX: Need to adjust checks to account for integer overflow */
if (len1 == 0 && len2 == 0) {
/* Regions *must* overlap if they both extend to the end */
result = TRUE;
} else if (len1 == 0 && start2+len2 < start1) {
/* Region 2 is completely to the left of Region 1 */
result = FALSE;
} else if (start1+len1 < start2 && len2 == 0) {
/* Region 1 is completely to the left of region 2 */
result = FALSE;
} else if (start1 + len1 <= start2 || start2+len2 <= start1) {
/* 1 is completely left of 2 or 2 is completely left of 1 */
result = FALSE;
} else {
result = TRUE;
}
return (result);
}
/*
* testlock(): inform the caller if the requested lock would be granted or not
* returns NULL if lock would granted, or pointer to the current nlm4_holder
* otherwise.
*/
struct nlm4_holder *
testlock(lock, exclusive, flags)
struct nlm4_lock *lock;
bool_t exclusive;
int flags;
{
struct file_lock *fl;
fhandle_t filehandle;
/* convert lock to a local filehandle */
memcpy(&filehandle, lock->fh.n_bytes, sizeof(filehandle));
siglock();
/* search through the list for lock holder */
for (fl = LIST_FIRST(&lcklst_head); fl != NULL;
fl = LIST_NEXT(fl, lcklst)) {
if (fl->status != LKST_LOCKED)
continue;
/*
* XXX: Could we possibly have identical filehandles
* on different systems?
* ie. Do we need to check more than just the filehandle?
* ie. Could someone artificially create requests which are
* security violations?
*/
if (memcmp(&fl->filehandle, &filehandle, sizeof(filehandle)))
continue;
/* File handles match, look for lock region overlap */
if (regions_overlap(lock->l_offset, lock->l_len,
fl->client.l_offset, fl->client.l_len)) {
syslog(LOG_DEBUG,
"Region overlap found %llu : %llu -- %llu : %llu\n",
lock->l_offset, lock->l_len,
fl->client.l_offset,fl->client.l_len);
/* Regions overlap. Now check for exclusivity. */
if (exclusive || fl->client.exclusive) {
/* Lock test must fail, regions are exclusive */
break;
}
}
/* Continue looping through all locks */
}
sigunlock();
if (fl == NULL) {
syslog(LOG_DEBUG, "test for %s: no lock found",
lock->caller_name);
return NULL;
} else {
syslog(LOG_DEBUG, "test for %s: found lock held by %s",
lock->caller_name, fl->client_name);
return (&fl->client);
}
}
/*
* getlock: try to aquire the lock.
* If file is already locked and we can sleep, put the lock in the list with
* status LKST_WAITING; it'll be processed later.
* Otherwise try to lock. If we're allowed to block, fork a child which
* will do the blocking lock.
*/
enum nlm_stats
getlock(lckarg, rqstp, flags)
nlm4_lockargs * lckarg;
struct svc_req *rqstp;
int flags;
{
struct file_lock *fl, *newfl;
enum nlm_stats retval;
if (grace_expired == 0 && lckarg->reclaim == 0)
return (flags & LOCK_V4) ?
nlm4_denied_grace_period : nlm_denied_grace_period;
/* allocate new file_lock for this request */
newfl = malloc(sizeof(struct file_lock));
if (newfl == NULL) {
syslog(LOG_NOTICE, "malloc failed: %s", strerror(errno));
/* failed */
return (flags & LOCK_V4) ?
nlm4_denied_nolocks : nlm_denied_nolocks;
}
if (lckarg->alock.fh.n_len != sizeof(fhandle_t)) {
syslog(LOG_DEBUG, "recieved fhandle size %d, local size %d",
lckarg->alock.fh.n_len, (int)sizeof(fhandle_t));
}
memcpy(&newfl->filehandle, lckarg->alock.fh.n_bytes, sizeof(fhandle_t));
newfl->addr = (struct sockaddr *)svc_getrpccaller(rqstp->rq_xprt)->buf;
newfl->client.exclusive = lckarg->exclusive;
newfl->client.svid = lckarg->alock.svid;
newfl->client.oh.n_bytes = malloc(lckarg->alock.oh.n_len);
if (newfl->client.oh.n_bytes == NULL) {
syslog(LOG_NOTICE, "malloc failed: %s", strerror(errno));
free(newfl);
return (flags & LOCK_V4) ?
nlm4_denied_nolocks : nlm_denied_nolocks;
}
newfl->client.oh.n_len = lckarg->alock.oh.n_len;
memcpy(newfl->client.oh.n_bytes, lckarg->alock.oh.n_bytes,
lckarg->alock.oh.n_len);
newfl->client.l_offset = lckarg->alock.l_offset;
newfl->client.l_len = lckarg->alock.l_len;
newfl->client_cookie.n_len = lckarg->cookie.n_len;
newfl->client_cookie.n_bytes = malloc(lckarg->cookie.n_len);
if (newfl->client_cookie.n_bytes == NULL) {
syslog(LOG_NOTICE, "malloc failed: %s", strerror(errno));
free(newfl->client.oh.n_bytes);
free(newfl);
return (flags & LOCK_V4) ?
nlm4_denied_nolocks : nlm_denied_nolocks;
}
memcpy(newfl->client_cookie.n_bytes, lckarg->cookie.n_bytes,
lckarg->cookie.n_len);
strncpy(newfl->client_name, lckarg->alock.caller_name, 128);
newfl->nsm_status = lckarg->state;
newfl->status = 0;
newfl->flags = flags;
siglock();
/* look for a lock rq from this host for this fh */
for (fl = LIST_FIRST(&lcklst_head); fl != NULL;
fl = LIST_NEXT(fl, lcklst)) {
if (memcmp(&newfl->filehandle, &fl->filehandle,
sizeof(fhandle_t)) == 0) {
if (strcmp(newfl->client_name, fl->client_name) == 0 &&
newfl->client.svid == fl->client.svid) {
/* already locked by this host ??? */
sigunlock();
syslog(LOG_NOTICE, "duplicate lock from %s",
newfl->client_name);
lfree(newfl);
switch(fl->status) {
case LKST_LOCKED:
return (flags & LOCK_V4) ?
nlm4_granted : nlm_granted;
case LKST_WAITING:
case LKST_PROCESSING:
return (flags & LOCK_V4) ?
nlm4_blocked : nlm_blocked;
case LKST_DYING:
return (flags & LOCK_V4) ?
nlm4_denied : nlm_denied;
default:
syslog(LOG_NOTICE, "bad status %d",
fl->status);
return (flags & LOCK_V4) ?
nlm4_failed : nlm_denied;
}
}
/*
* We already have a lock for this file. Put this one
* in waiting state if allowed to block
*/
if (lckarg->block) {
syslog(LOG_DEBUG, "lock from %s: already "
"locked, waiting",
lckarg->alock.caller_name);
newfl->status = LKST_WAITING;
LIST_INSERT_HEAD(&lcklst_head, newfl, lcklst);
do_mon(lckarg->alock.caller_name);
sigunlock();
return (flags & LOCK_V4) ?
nlm4_blocked : nlm_blocked;
} else {
sigunlock();
syslog(LOG_DEBUG, "lock from %s: already "
"locked, failed",
lckarg->alock.caller_name);
lfree(newfl);
return (flags & LOCK_V4) ?
nlm4_denied : nlm_denied;
}
}
}
/* no entry for this file yet; add to list */
LIST_INSERT_HEAD(&lcklst_head, newfl, lcklst);
/* do the lock */
retval = do_lock(newfl, lckarg->block);
switch (retval) {
case nlm4_granted:
/* case nlm_granted: is the same as nlm4_granted */
case nlm4_blocked:
/* case nlm_blocked: is the same as nlm4_blocked */
do_mon(lckarg->alock.caller_name);
break;
default:
lfree(newfl);
break;
}
sigunlock();
return retval;
}
/* unlock a filehandle */
enum nlm_stats
unlock(lck, flags)
nlm4_lock *lck;
int flags;
{
struct file_lock *fl;
fhandle_t filehandle;
int err = (flags & LOCK_V4) ? nlm4_granted : nlm_granted;
memcpy(&filehandle, lck->fh.n_bytes, sizeof(fhandle_t));
siglock();
for (fl = LIST_FIRST(&lcklst_head); fl != NULL;
fl = LIST_NEXT(fl, lcklst)) {
if (strcmp(fl->client_name, lck->caller_name) ||
memcmp(&filehandle, &fl->filehandle, sizeof(fhandle_t)) ||
fl->client.oh.n_len != lck->oh.n_len ||
memcmp(fl->client.oh.n_bytes, lck->oh.n_bytes,
fl->client.oh.n_len) != 0 ||
fl->client.svid != lck->svid)
continue;
/* Got it, unlock and remove from the queue */
syslog(LOG_DEBUG, "unlock from %s: found struct, status %d",
lck->caller_name, fl->status);
switch (fl->status) {
case LKST_LOCKED:
err = do_unlock(fl);
break;
case LKST_WAITING:
/* remove from the list */
LIST_REMOVE(fl, lcklst);
lfree(fl);
break;
case LKST_PROCESSING:
/*
* being handled by a child; will clean up
* when the child exits
*/
fl->status = LKST_DYING;
break;
case LKST_DYING:
/* nothing to do */
break;
default:
syslog(LOG_NOTICE, "unknow status %d for %s",
fl->status, fl->client_name);
}
sigunlock();
return err;
}
sigunlock();
/* didn't find a matching entry; log anyway */
syslog(LOG_NOTICE, "no matching entry for %s",
lck->caller_name);
return (flags & LOCK_V4) ? nlm4_granted : nlm_granted;
}
void
lfree(fl)
struct file_lock *fl;
{
free(fl->client.oh.n_bytes);
free(fl->client_cookie.n_bytes);
free(fl);
}
void
sigchild_handler(sig)
int sig;
{
int status;
pid_t pid;
struct file_lock *fl;
while (1) {
pid = wait4(-1, &status, WNOHANG, NULL);
if (pid == -1) {
if (errno != ECHILD)
syslog(LOG_NOTICE, "wait failed: %s",
strerror(errno));
else
syslog(LOG_DEBUG, "wait failed: %s",
strerror(errno));
return;
}
if (pid == 0) {
/* no more child to handle yet */
return;
}
/*
* if we're here we have a child that exited
* Find the associated file_lock.
*/
for (fl = LIST_FIRST(&lcklst_head); fl != NULL;
fl = LIST_NEXT(fl, lcklst)) {
if (pid == fl->locker)
break;
}
if (pid != fl->locker) {
syslog(LOG_NOTICE, "unknow child %d", pid);
} else {
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
syslog(LOG_NOTICE, "child %d failed", pid);
/*
* can't do much here; we can't reply
* anything but OK for blocked locks
* Eventually the client will time out
* and retry.
*/
do_unlock(fl);
return;
}
/* check lock status */
syslog(LOG_DEBUG, "processing child %d, status %d",
pid, fl->status);
switch(fl->status) {
case LKST_PROCESSING:
fl->status = LKST_LOCKED;
send_granted(fl, (fl->flags & LOCK_V4) ?
nlm4_granted : nlm_granted);
break;
case LKST_DYING:
do_unlock(fl);
break;
default:
syslog(LOG_NOTICE, "bad lock status (%d) for"
" child %d", fl->status, pid);
}
}
}
}
/*
*
* try to aquire the lock described by fl. Eventually fock a child to do a
* blocking lock if allowed and required.
*/
enum nlm_stats
do_lock(fl, block)
struct file_lock *fl;
int block;
{
int lflags, error;
struct stat st;
fl->fd = fhopen(&fl->filehandle, O_RDWR);
if (fl->fd < 0) {
switch (errno) {
case ESTALE:
error = nlm4_stale_fh;
break;
case EROFS:
error = nlm4_rofs;
break;
default:
error = nlm4_failed;
}
if ((fl->flags & LOCK_V4) == 0)
error = nlm_denied;
syslog(LOG_NOTICE, "fhopen failed (from %s): %s",
fl->client_name, strerror(errno));
LIST_REMOVE(fl, lcklst);
return error;;
}
if (fstat(fl->fd, &st) < 0) {
syslog(LOG_NOTICE, "fstat failed (from %s): %s",
fl->client_name, strerror(errno));
}
syslog(LOG_DEBUG, "lock from %s for file%s%s: dev %d ino %d (uid %d), "
"flags %d",
fl->client_name, fl->client.exclusive ? " (exclusive)":"",
block ? " (block)":"",
st.st_dev, st.st_ino, st.st_uid, fl->flags);
lflags = LOCK_NB;
if (fl->client.exclusive == 0)
lflags |= LOCK_SH;
else
lflags |= LOCK_EX;
error = flock(fl->fd, lflags);
if (error != 0 && errno == EAGAIN && block) {
switch (fl->locker = fork()) {
case -1: /* fork failed */
syslog(LOG_NOTICE, "fork failed: %s", strerror(errno));
LIST_REMOVE(fl, lcklst);
close(fl->fd);
return (fl->flags & LOCK_V4) ?
nlm4_denied_nolocks : nlm_denied_nolocks;
case 0:
/*
* Attempt a blocking lock. Will have to call
* NLM_GRANTED later.
*/
setproctitle("%s", fl->client_name);
lflags &= ~LOCK_NB;
if(flock(fl->fd, lflags) != 0) {
syslog(LOG_NOTICE, "flock failed: %s",
strerror(errno));
exit(-1);
}
/* lock granted */
exit(0);
default:
syslog(LOG_DEBUG, "lock request from %s: forked %d",
fl->client_name, fl->locker);
fl->status = LKST_PROCESSING;
return (fl->flags & LOCK_V4) ?
nlm4_blocked : nlm_blocked;
}
}
/* non block case */
if (error != 0) {
switch (errno) {
case EAGAIN:
error = nlm4_denied;
break;
case ESTALE:
error = nlm4_stale_fh;
break;
case EROFS:
error = nlm4_rofs;
break;
default:
error = nlm4_failed;
}
if ((fl->flags & LOCK_V4) == 0)
error = nlm_denied;
if (errno != EAGAIN)
syslog(LOG_NOTICE, "flock for %s failed: %s",
fl->client_name, strerror(errno));
else syslog(LOG_DEBUG, "flock for %s failed: %s",
fl->client_name, strerror(errno));
LIST_REMOVE(fl, lcklst);
close(fl->fd);
return error;
}
fl->status = LKST_LOCKED;
return (fl->flags & LOCK_V4) ? nlm4_granted : nlm_granted;
}
void
send_granted(fl, opcode)
struct file_lock *fl;
int opcode;
{
CLIENT *cli;
static char dummy;
struct timeval timeo;
int success;
static struct nlm_res retval;
static struct nlm4_res retval4;
cli = get_client(fl->addr,
(fl->flags & LOCK_V4) ? NLM_VERS4 : NLM_VERS);
if (cli == NULL) {
syslog(LOG_NOTICE, "failed to get CLIENT for %s",
fl->client_name);
/*
* We fail to notify remote that the lock has been granted.
* The client will timeout and retry, the lock will be
* granted at this time.
*/
return;
}
timeo.tv_sec = 0;
timeo.tv_usec = (fl->flags & LOCK_ASYNC) ? 0 : 500000; /* 0.5s */
if (fl->flags & LOCK_V4) {
static nlm4_testargs res;
res.cookie = fl->client_cookie;
res.exclusive = fl->client.exclusive;
res.alock.caller_name = fl->client_name;
res.alock.fh.n_len = sizeof(fhandle_t);
res.alock.fh.n_bytes = (char*)&fl->filehandle;
res.alock.oh = fl->client.oh;
res.alock.svid = fl->client.svid;
res.alock.l_offset = fl->client.l_offset;
res.alock.l_len = fl->client.l_len;
syslog(LOG_DEBUG, "sending v4 reply%s",
(fl->flags & LOCK_ASYNC) ? " (async)":"");
if (fl->flags & LOCK_ASYNC) {
success = clnt_call(cli, NLM4_GRANTED_MSG,
xdr_nlm4_testargs, &res, xdr_void, &dummy, timeo);
} else {
success = clnt_call(cli, NLM4_GRANTED,
xdr_nlm4_testargs, &res, xdr_nlm4_res,
&retval4, timeo);
}
} else {
static nlm_testargs res;
res.cookie = fl->client_cookie;
res.exclusive = fl->client.exclusive;
res.alock.caller_name = fl->client_name;
res.alock.fh.n_len = sizeof(fhandle_t);
res.alock.fh.n_bytes = (char*)&fl->filehandle;
res.alock.oh = fl->client.oh;
res.alock.svid = fl->client.svid;
res.alock.l_offset = fl->client.l_offset;
res.alock.l_len = fl->client.l_len;
syslog(LOG_DEBUG, "sending v1 reply%s",
(fl->flags & LOCK_ASYNC) ? " (async)":"");
if (fl->flags & LOCK_ASYNC) {
success = clnt_call(cli, NLM_GRANTED_MSG,
xdr_nlm_testargs, &res, xdr_void, &dummy, timeo);
} else {
success = clnt_call(cli, NLM_GRANTED,
xdr_nlm_testargs, &res, xdr_nlm_res,
&retval, timeo);
}
}
if (debug_level > 2)
syslog(LOG_DEBUG, "clnt_call returns %d(%s) for granted",
success, clnt_sperrno(success));
}
enum nlm_stats
do_unlock(rfl)
struct file_lock *rfl;
{
struct file_lock *fl;
int error;
int lockst;
/* unlock the file: closing is enouth ! */
if (close(rfl->fd) < 0) {
if (errno == ESTALE)
error = nlm4_stale_fh;
else
error = nlm4_failed;
if ((fl->flags & LOCK_V4) == 0)
error = nlm_denied;
syslog(LOG_NOTICE,
"close failed (from %s): %s",
rfl->client_name, strerror(errno));
} else {
error = (fl->flags & LOCK_V4) ?
nlm4_granted : nlm_granted;
}
LIST_REMOVE(rfl, lcklst);
/* process the next LKST_WAITING lock request for this fh */
for (fl = LIST_FIRST(&lcklst_head); fl != NULL;
fl = LIST_NEXT(fl, lcklst)) {
if (fl->status != LKST_WAITING ||
memcmp(&rfl->filehandle, &fl->filehandle,
sizeof(fhandle_t)) != 0)
continue;
lockst = do_lock(fl, 1); /* If it's LKST_WAITING we can block */
switch (lockst) {
case nlm4_granted:
/* case nlm_granted: same as nlm4_granted */
send_granted(fl, (fl->flags & LOCK_V4) ?
nlm4_granted : nlm_granted);
break;
case nlm4_blocked:
/* case nlm_blocked: same as nlm4_blocked */
break;
default:
lfree(fl);
break;
}
break;
}
return error;
}
void
siglock()
{
sigset_t block;
sigemptyset(&block);
sigaddset(&block, SIGCHLD);
if (sigprocmask(SIG_BLOCK, &block, NULL) < 0) {
syslog(LOG_WARNING, "siglock failed: %s", strerror(errno));
}
}
void
sigunlock()
{
sigset_t block;
sigemptyset(&block);
sigaddset(&block, SIGCHLD);
if (sigprocmask(SIG_UNBLOCK, &block, NULL) < 0) {
syslog(LOG_WARNING, "sigunlock failed: %s", strerror(errno));
}
}
/* monitor a host through rpc.statd, and keep a ref count */
void
do_mon(hostname)
char *hostname;
{
struct host *hp;
struct mon my_mon;
struct sm_stat_res res;
int retval;
for (hp = LIST_FIRST(&hostlst_head); hp != NULL;
hp = LIST_NEXT(hp, hostlst)) {
if (strcmp(hostname, hp->name) == 0) {
/* already monitored, just bump refcnt */
hp->refcnt++;
return;
}
}
/* not found, have to create an entry for it */
hp = malloc(sizeof(struct host));
strncpy(hp->name, hostname, SM_MAXSTRLEN);
hp->refcnt = 1;
syslog(LOG_DEBUG, "monitoring host %s",
hostname);
memset(&my_mon, 0, sizeof(my_mon));
my_mon.mon_id.mon_name = hp->name;
my_mon.mon_id.my_id.my_name = "localhost";
my_mon.mon_id.my_id.my_prog = NLM_PROG;
my_mon.mon_id.my_id.my_vers = NLM_SM;
my_mon.mon_id.my_id.my_proc = NLM_SM_NOTIFY;
if ((retval =
callrpc("localhost", SM_PROG, SM_VERS, SM_MON, xdr_mon,
(char*)&my_mon, xdr_sm_stat_res, (char*)&res)) != 0) {
syslog(LOG_WARNING, "rpc to statd failed: %s",
clnt_sperrno((enum clnt_stat)retval));
free(hp);
return;
}
if (res.res_stat == stat_fail) {
syslog(LOG_WARNING, "statd failed");
free(hp);
return;
}
LIST_INSERT_HEAD(&hostlst_head, hp, hostlst);
}
void
notify(hostname, state)
char *hostname;
int state;
{
struct file_lock *fl, *next_fl;
int err;
syslog(LOG_DEBUG, "notify from %s, new state %d", hostname, state);
/* search all lock for this host; if status changed, release the lock */
siglock();
for (fl = LIST_FIRST(&lcklst_head); fl != NULL; fl = next_fl) {
next_fl = LIST_NEXT(fl, lcklst);
if (strcmp(hostname, fl->client_name) == 0 &&
fl->nsm_status != state) {
syslog(LOG_DEBUG, "state %d, nsm_state %d, unlocking",
fl->status, fl->nsm_status);
switch(fl->status) {
case LKST_LOCKED:
err = do_unlock(fl);
if (err != nlm_granted)
syslog(LOG_DEBUG,
"notify: unlock failed for %s (%d)",
hostname, err);
break;
case LKST_WAITING:
LIST_REMOVE(fl, lcklst);
lfree(fl);
break;
case LKST_PROCESSING:
fl->status = LKST_DYING;
break;
case LKST_DYING:
break;
default:
syslog(LOG_NOTICE, "unknow status %d for %s",
fl->status, fl->client_name);
}
}
}
sigunlock();
}