umount.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* -----------------------------------------------------------------
*
* umount.c
*
* CFS specific umount command.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <limits.h>
#include <errno.h>
#include <wait.h>
#include <ctype.h>
#include <fcntl.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/fcntl.h>
#include <sys/mount.h>
#include <sys/mntent.h>
#include <sys/mnttab.h>
#include <sys/fs/cachefs_fs.h>
#include <fslib.h>
#include <sys/utsname.h>
#include <rpc/rpc.h>
#include "../common/subr.h"
#include "../common/cachefsd.h"
/* forward references */
void pr_err(char *fmt, ...);
void usage(char *msgp);
int daemon_unmount(char *mntptp, int);
/*
*
* main
*
* Description:
* Main routine for the cfs umount program.
* Arguments:
* argc number of command line arguments
* argv list of command line arguments
* Returns:
* Returns 0 for success or 1 if an error occurs.
* Preconditions:
*/
int
main(int argc, char **argv)
{
char *strp;
int xx;
int ret;
struct mnttab mget;
struct mnttab mref;
FILE *finp;
char mnt_front[PATH_MAX];
char mnt_back[PATH_MAX];
char *p, mnt_frontns[PATH_MAX];
pid_t pid;
int stat_loc;
char *cachedirp, *s;
int ufd, c;
int flag = 0;
(void) setlocale(LC_ALL, "");
#if !defined(TEXT_DOMAIN)
#define TEXT_DOMAIN "SYS_TEST"
#endif
(void) textdomain(TEXT_DOMAIN);
/*
* Set options
*/
while ((c = getopt(argc, argv, "f")) != EOF) {
switch (c) {
case 'f':
flag |= MS_FORCE; /* forced unmount is desired */
break;
default:
usage("Incorrect number of arguments specified");
return (1);
}
}
if (flag & MS_FORCE)
strcpy(mnt_front, argv[2]);
else
strcpy(mnt_front, argv[1]);
mnt_back[0] = '\0';
if (strlen(argv[1]) >= (size_t)PATH_MAX) {
pr_err(gettext("name too long"));
return (1);
}
/*
* An unmount from autofs may have a
* space appended to the path.
* Trim it off before attempting to
* match the mountpoint in mnttab
*/
strcpy(mnt_frontns, mnt_front);
p = &mnt_frontns[strlen(mnt_frontns) - 1];
if (*p == ' ')
*p = '\0';
/* get the mount point and the back file system mount point */
finp = fopen(MNTTAB, "r");
if (finp) {
mntnull(&mref);
mref.mnt_mountp = mnt_frontns;
mref.mnt_fstype = "cachefs";
ret = getmntany(finp, &mget, &mref);
cachedirp = (char *)malloc(strlen(mget.mnt_special) + 1);
strcpy(cachedirp, mget.mnt_special);
/*
* AutoClient mounts do not have .cfs_mnt_points string in
* them, so strstr would return NULL. So .cfs_unmnt file
* is not updated.
*/
if ((s = strstr(cachedirp, ".cfs_mnt_points")) != NULL) {
time32_t btime;
xx = -1;
cachedirp[s-cachedirp] = '\0';
strcat(cachedirp, CACHEFS_UNMNT_FILE);
if ((ufd = open(cachedirp, O_WRONLY|O_CREAT|O_TRUNC,
0600)) > 0) {
if ((btime = get_boottime()) != -1)
xx = write(ufd, &btime, sizeof (time32_t));
close(ufd);
}
if (xx < 0)
pr_err(gettext(".cfs_unmnt error"));
}
if (ret != -1) {
if (mget.mnt_special)
strcpy(mnt_back, mget.mnt_special);
} else {
mref.mnt_special = mref.mnt_mountp;
mref.mnt_mountp = NULL;
rewind(finp);
ret = getmntany(finp, &mget, &mref);
if (ret != -1) {
strcpy(mnt_front, mget.mnt_mountp);
if (mget.mnt_special)
strcpy(mnt_back, mget.mnt_special);
} else {
pr_err(gettext("warning: %s not in mnttab"),
mref.mnt_special);
}
}
fclose(finp);
}
/* try to get the daemon to unmount this file system for us */
xx = daemon_unmount(mnt_front, flag);
if (xx == ENOTSUP)
return (1);
if (xx == EBUSY) {
pr_err(gettext("%s %s"), mnt_front, strerror(xx));
return (1);
}
if (xx == EIO) {
/* try to unmount the file system directly */
if (umount2(mnt_front, flag) == -1) {
pr_err(gettext("%s %s"), mnt_front, strerror(errno));
return (1);
}
}
/* if we do not know the name of the back file system mount point */
if (mnt_back[0] == '\0') {
/* all done */
return (0);
}
/*
* If the back file system was mounted on a directory with a
* parent name of BACKMNT_NAME then we assume that we
* mounted it and that it is okay to try to umount it.
*/
if (strstr(mnt_back, BACKMNT_NAME) == NULL)
return (0);
/* if no back file system mounted */
if (strcmp(mnt_back, "nobackfs") == 0)
return (0);
/* fork */
if ((pid = fork()) == -1) {
pr_err(gettext("could not fork %s"), strerror(errno));
return (1);
}
/* if the child */
if (pid == 0) {
/* invoke the umount command on the back file system */
xx = execl("/sbin/umount", "/sbin/umount", mnt_back, NULL);
pr_err(gettext("could not exec /sbin/umount"
" on back file system %s"), strerror(errno));
}
/* else if the parent */
else {
/* wait for the child to exit */
if (wait(&stat_loc) == -1) {
pr_err(gettext("wait failed %s"), strerror(errno));
return (1);
}
if (!WIFEXITED(stat_loc)) {
pr_err(gettext("back umount did not exit"));
return (1);
}
xx = WEXITSTATUS(stat_loc);
if (xx) {
pr_err(gettext("back umount failed"));
return (xx);
}
}
/* delete the back file system mount point since we created it */
rmdir(mnt_back);
return (xx);
}
/*
*
* pr_err
*
* Description:
* Prints an error message to stderr.
* Arguments:
* fmt printf style format
* ... arguments for fmt
* Returns:
* Preconditions:
* precond(fmt)
*/
void
pr_err(char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
(void) fprintf(stderr, gettext("umount -F cachefs: "));
(void) vfprintf(stderr, fmt, ap);
(void) fprintf(stderr, "\n");
va_end(ap);
}
/*
*
* usage
*
* Description:
* Prints a usage message.
* Arguments:
* An optional additional message to be displayed.
* Returns:
* Preconditions:
*/
void
usage(char *msgp)
{
if (msgp)
pr_err(gettext("%s"), msgp);
fprintf(stderr, gettext("Usage: umount -F cachefs dir"));
}
/*
*
* daemon_unmount
*
* Description:
* Notifies the cachefsd of an unmount request.
* Arguments:
* Mount point to unmount.
* Returns:
* Returns 0 if the cachefsd unmounted the file system
* EIO if should try unmount directly
* EBUSY if did not unmount because busy
* EAGAIN if umounted but should not unmount nfs mount
*
* Preconditions:
* precond(mntptp)
*/
int
daemon_unmount(char *mntptp, int flag)
{
CLIENT *clnt;
enum clnt_stat retval;
int xx;
int result;
char *hostp;
struct utsname info;
static struct timeval TIMEOUT = { 60*60, 0 };
static struct timeval create_timeout = { 5, 0};
struct cachefsd_fs_unmounted uargs;
/* get the host name */
xx = uname(&info);
if (xx == -1) {
pr_err(gettext("cannot get host name, errno %d"), errno);
return (EIO);
}
hostp = info.nodename;
uargs.mntpt = mntptp;
uargs.flag = flag;
/* creat the connection to the daemon */
clnt = clnt_create_timed(hostp, CACHEFSDPROG, CACHEFSDVERS, "local",
&create_timeout);
if (clnt == NULL) {
pr_err(gettext("cachefsd is not running"));
return (EIO);
}
clnt_control(clnt, CLSET_TIMEOUT, (char *)&TIMEOUT);
retval = cachefsd_fs_unmounted_1(&uargs, &result, clnt);
if (retval != RPC_SUCCESS) {
clnt_perror(clnt, gettext("cachefsd is not responding"));
clnt_destroy(clnt);
return (EIO);
}
clnt_destroy(clnt);
return (result);
}