/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (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
*/
/*
* Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
* Copyright (c) 2011 Lawrence Livermore National Security, LLC.
*/
#include <libintl.h>
#include <unistd.h>
#include <sys/file.h>
#include <sys/mount.h>
#include <sys/mntent.h>
#include <sys/stat.h>
#include <libzfs.h>
#include <libzutil.h>
#include <locale.h>
#include <getopt.h>
#include <fcntl.h>
#include <errno.h>
#define ZS_COMMENT 0x00000000 /* comment */
#define ZS_ZFSUTIL 0x00000001 /* caller is zfs(8) */
libzfs_handle_t *g_zfs;
/*
* Return the pool/dataset to mount given the name passed to mount. This
* is expected to be of the form pool/dataset, however may also refer to
* a block device if that device contains a valid zfs label.
*/
static char *
parse_dataset(char *dataset)
{
char cwd[PATH_MAX];
struct stat64 statbuf;
int error;
int len;
/*
* We expect a pool/dataset to be provided, however if we're
* given a device which is a member of a zpool we attempt to
* extract the pool name stored in the label. Given the pool
* name we can mount the root dataset.
*/
error = stat64(dataset, &statbuf);
if (error == 0) {
nvlist_t *config;
char *name;
int fd;
fd = open(dataset, O_RDONLY);
if (fd < 0)
goto out;
error = zpool_read_label(fd, &config, NULL);
(void) close(fd);
if (error)
goto out;
error = nvlist_lookup_string(config,
ZPOOL_CONFIG_POOL_NAME, &name);
if (error) {
nvlist_free(config);
} else {
dataset = strdup(name);
nvlist_free(config);
return (dataset);
}
}
out:
/*
* If a file or directory in your current working directory is
* named 'dataset' then mount(8) will prepend your current working
* directory to the dataset. There is no way to prevent this
* behavior so we simply check for it and strip the prepended
* patch when it is added.
*/
if (getcwd(cwd, PATH_MAX) == NULL)
return (dataset);
len = strlen(cwd);
/* Do not add one when cwd already ends in a trailing '/' */
if (strncmp(cwd, dataset, len) == 0)
return (dataset + len + (cwd[len-1] != '/'));
return (dataset);
}
/*
* Update the mtab_* code to use the libmount library when it is commonly
* available otherwise fallback to legacy mode. The mount(8) utility will
* manage the lock file for us to prevent racing updates to /etc/mtab.
*/
static int
mtab_is_writeable(void)
{
struct stat st;
int error, fd;
error = lstat("/etc/mtab", &st);
if (error || S_ISLNK(st.st_mode))
return (0);
fd = open("/etc/mtab", O_RDWR | O_CREAT, 0644);
if (fd < 0)
return (0);
close(fd);
return (1);
}
static int
mtab_update(char *dataset, char *mntpoint, char *type, char *mntopts)
{
struct mntent mnt;
FILE *fp;
int error;
mnt.mnt_fsname = dataset;
mnt.mnt_dir = mntpoint;
mnt.mnt_type = type;
mnt.mnt_opts = mntopts ? mntopts : "";
mnt.mnt_freq = 0;
mnt.mnt_passno = 0;
fp = setmntent("/etc/mtab", "a+");
if (!fp) {
(void) fprintf(stderr, gettext(
"filesystem '%s' was mounted, but /etc/mtab "
"could not be opened due to error %d\n"),
dataset, errno);
return (MOUNT_FILEIO);
}
error = addmntent(fp, &mnt);
if (error) {
(void) fprintf(stderr, gettext(
"filesystem '%s' was mounted, but /etc/mtab "
"could not be updated due to error %d\n"),
dataset, errno);
return (MOUNT_FILEIO);
}
(void) endmntent(fp);
return (MOUNT_SUCCESS);
}
int
main(int argc, char **argv)
{
zfs_handle_t *zhp;
char prop[ZFS_MAXPROPLEN];
uint64_t zfs_version = 0;
char mntopts[MNT_LINE_MAX] = { '\0' };
char badopt[MNT_LINE_MAX] = { '\0' };
char mtabopt[MNT_LINE_MAX] = { '\0' };
char mntpoint[PATH_MAX];
char *dataset;
unsigned long mntflags = 0, zfsflags = 0, remount = 0;
int sloppy = 0, fake = 0, verbose = 0, nomtab = 0, zfsutil = 0;
int error, c;
(void) setlocale(LC_ALL, "");
(void) setlocale(LC_NUMERIC, "C");
(void) textdomain(TEXT_DOMAIN);
opterr = 0;
/* check options */
while ((c = getopt_long(argc, argv, "sfnvo:h?", 0, 0)) != -1) {
switch (c) {
case 's':
sloppy = 1;
break;
case 'f':
fake = 1;
break;
case 'n':
nomtab = 1;
break;
case 'v':
verbose++;
break;
case 'o':
(void) strlcpy(mntopts, optarg, sizeof (mntopts));
break;
case 'h':
case '?':
(void) fprintf(stderr, gettext("Invalid option '%c'\n"),
optopt);
(void) fprintf(stderr, gettext("Usage: mount.zfs "
"[-sfnv] [-o options] <dataset> <mountpoint>\n"));
return (MOUNT_USAGE);
}
}
argc -= optind;
argv += optind;
/* check that we only have two arguments */
if (argc != 2) {
if (argc == 0)
(void) fprintf(stderr, gettext("missing dataset "
"argument\n"));
else if (argc == 1)
(void) fprintf(stderr,
gettext("missing mountpoint argument\n"));
else
(void) fprintf(stderr, gettext("too many arguments\n"));
(void) fprintf(stderr, "usage: mount <dataset> <mountpoint>\n");
return (MOUNT_USAGE);
}
dataset = parse_dataset(argv[0]);
/* canonicalize the mount point */
if (realpath(argv[1], mntpoint) == NULL) {
(void) fprintf(stderr, gettext("filesystem '%s' cannot be "
"mounted at '%s' due to canonicalization error %d.\n"),
dataset, argv[1], errno);
return (MOUNT_SYSERR);
}
/* validate mount options and set mntflags */
error = zfs_parse_mount_options(mntopts, &mntflags, &zfsflags, sloppy,
badopt, mtabopt);
if (error) {
switch (error) {
case ENOMEM:
(void) fprintf(stderr, gettext("filesystem '%s' "
"cannot be mounted due to a memory allocation "
"failure.\n"), dataset);
return (MOUNT_SYSERR);
case ENOENT:
(void) fprintf(stderr, gettext("filesystem '%s' "
"cannot be mounted due to invalid option "
"'%s'.\n"), dataset, badopt);
(void) fprintf(stderr, gettext("Use the '-s' option "
"to ignore the bad mount option.\n"));
return (MOUNT_USAGE);
default:
(void) fprintf(stderr, gettext("filesystem '%s' "
"cannot be mounted due to internal error %d.\n"),
dataset, error);
return (MOUNT_SOFTWARE);
}
}
if (verbose)
(void) fprintf(stdout, gettext("mount.zfs:\n"
" dataset: \"%s\"\n mountpoint: \"%s\"\n"
" mountflags: 0x%lx\n zfsflags: 0x%lx\n"
" mountopts: \"%s\"\n mtabopts: \"%s\"\n"),
dataset, mntpoint, mntflags, zfsflags, mntopts, mtabopt);
if (mntflags & MS_REMOUNT) {
nomtab = 1;
remount = 1;
}
if (zfsflags & ZS_ZFSUTIL)
zfsutil = 1;
if ((g_zfs = libzfs_init()) == NULL) {
(void) fprintf(stderr, "%s\n", libzfs_error_init(errno));
return (MOUNT_SYSERR);
}
/* try to open the dataset to access the mount point */
if ((zhp = zfs_open(g_zfs, dataset,
ZFS_TYPE_FILESYSTEM | ZFS_TYPE_SNAPSHOT)) == NULL) {
(void) fprintf(stderr, gettext("filesystem '%s' cannot be "
"mounted, unable to open the dataset\n"), dataset);
libzfs_fini(g_zfs);
return (MOUNT_USAGE);
}
zfs_adjust_mount_options(zhp, mntpoint, mntopts, mtabopt);
/* treat all snapshots as legacy mount points */
if (zfs_get_type(zhp) == ZFS_TYPE_SNAPSHOT)
(void) strlcpy(prop, ZFS_MOUNTPOINT_LEGACY, ZFS_MAXPROPLEN);
else
(void) zfs_prop_get(zhp, ZFS_PROP_MOUNTPOINT, prop,
sizeof (prop), NULL, NULL, 0, B_FALSE);
/*
* Fetch the max supported zfs version in case we get ENOTSUP
* back from the mount command, since we need the zfs handle
* to do so.
*/
zfs_version = zfs_prop_get_int(zhp, ZFS_PROP_VERSION);
if (zfs_version == 0) {
fprintf(stderr, gettext("unable to fetch "
"ZFS version for filesystem '%s'\n"), dataset);
return (MOUNT_SYSERR);
}
zfs_close(zhp);
libzfs_fini(g_zfs);
/*
* Legacy mount points may only be mounted using 'mount', never using
* 'zfs mount'. However, since 'zfs mount' actually invokes 'mount'
* we differentiate the two cases using the 'zfsutil' mount option.
* This mount option should only be supplied by the 'zfs mount' util.
*
* The only exception to the above rule is '-o remount' which is
* always allowed for non-legacy datasets. This is done because when
* using zfs as your root file system both rc.sysinit/umountroot and
* systemd depend on 'mount -o remount <mountpoint>' to work.
*/
if (zfsutil && (strcmp(prop, ZFS_MOUNTPOINT_LEGACY) == 0)) {
(void) fprintf(stderr, gettext(
"filesystem '%s' cannot be mounted using 'zfs mount'.\n"
"Use 'zfs set mountpoint=%s' or 'mount -t zfs %s %s'.\n"
"See zfs(8) for more information.\n"),
dataset, mntpoint, dataset, mntpoint);
return (MOUNT_USAGE);
}
if (!zfsutil && !(remount || fake) &&
strcmp(prop, ZFS_MOUNTPOINT_LEGACY)) {
(void) fprintf(stderr, gettext(
"filesystem '%s' cannot be mounted using 'mount'.\n"
"Use 'zfs set mountpoint=%s' or 'zfs mount %s'.\n"
"See zfs(8) for more information.\n"),
dataset, "legacy", dataset);
return (MOUNT_USAGE);
}
if (!fake) {
error = mount(dataset, mntpoint, MNTTYPE_ZFS,
mntflags, mntopts);
}
if (error) {
switch (errno) {
case ENOENT:
(void) fprintf(stderr, gettext("mount point "
"'%s' does not exist\n"), mntpoint);
return (MOUNT_SYSERR);
case EBUSY:
(void) fprintf(stderr, gettext("filesystem "
"'%s' is already mounted\n"), dataset);
return (MOUNT_BUSY);
case ENOTSUP:
if (zfs_version > ZPL_VERSION) {
(void) fprintf(stderr,
gettext("filesystem '%s' (v%d) is not "
"supported by this implementation of "
"ZFS (max v%d).\n"), dataset,
(int)zfs_version, (int)ZPL_VERSION);
} else {
(void) fprintf(stderr,
gettext("filesystem '%s' mount "
"failed for unknown reason.\n"), dataset);
}
return (MOUNT_SYSERR);
#ifdef MS_MANDLOCK
case EPERM:
if (mntflags & MS_MANDLOCK) {
(void) fprintf(stderr, gettext("filesystem "
"'%s' has the 'nbmand=on' property set, "
"this mount\noption may be disabled in "
"your kernel. Use 'zfs set nbmand=off'\n"
"to disable this option and try to "
"mount the filesystem again.\n"), dataset);
return (MOUNT_SYSERR);
}
/* fallthru */
#endif
default:
(void) fprintf(stderr, gettext("filesystem "
"'%s' can not be mounted: %s\n"), dataset,
strerror(errno));
return (MOUNT_USAGE);
}
}
if (!nomtab && mtab_is_writeable()) {
error = mtab_update(dataset, mntpoint, MNTTYPE_ZFS, mtabopt);
if (error)
return (error);
}
return (MOUNT_SUCCESS);
}