freebsd-dev/cmd/mount_zfs/mount_zfs.c

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/*
* 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>
Update build system and packaging Minimal changes required to integrate the SPL sources in to the ZFS repository build infrastructure and packaging. Build system and packaging: * Renamed SPL_* autoconf m4 macros to ZFS_*. * Removed redundant SPL_* autoconf m4 macros. * Updated the RPM spec files to remove SPL package dependency. * The zfs package obsoletes the spl package, and the zfs-kmod package obsoletes the spl-kmod package. * The zfs-kmod-devel* packages were updated to add compatibility symlinks under /usr/src/spl-x.y.z until all dependent packages can be updated. They will be removed in a future release. * Updated copy-builtin script for in-kernel builds. * Updated DKMS package to include the spl.ko. * Updated stale AUTHORS file to include all contributors. * Updated stale COPYRIGHT and included the SPL as an exception. * Renamed README.markdown to README.md * Renamed OPENSOLARIS.LICENSE to LICENSE. * Renamed DISCLAIMER to NOTICE. Required code changes: * Removed redundant HAVE_SPL macro. * Removed _BOOT from nvpairs since it doesn't apply for Linux. * Initial header cleanup (removal of empty headers, refactoring). * Remove SPL repository clone/build from zimport.sh. * Use of DEFINE_RATELIMIT_STATE and DEFINE_SPINLOCK removed due to build issues when forcing C99 compilation. * Replaced legacy ACCESS_ONCE with READ_ONCE. * Include needed headers for `current` and `EXPORT_SYMBOL`. Reviewed-by: Tony Hutter <hutter2@llnl.gov> Reviewed-by: Olaf Faaland <faaland1@llnl.gov> Reviewed-by: Matthew Ahrens <mahrens@delphix.com> Reviewed-by: Pavel Zakharov <pavel.zakharov@delphix.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> TEST_ZIMPORT_SKIP="yes" Closes #7556
2018-02-16 01:53:18 +00:00
#include <errno.h>
#define ZS_COMMENT 0x00000000 /* comment */
#define ZS_ZFSUTIL 0x00000001 /* caller is zfs(8) */
libzfs_handle_t *g_zfs;
/*
* Opportunistically convert a target string into a pool name. If the
* string does not represent a block device with a valid zfs label
* then it is passed through without modification.
*/
static void
parse_dataset(const char *target, char **dataset)
{
/*
* Prior to util-linux 2.36.2, if a file or directory in the
* current working directory was named 'dataset' then mount(8)
* would prepend the current working directory to the dataset.
* Check for it and strip the prepended path when it is added.
*/
char cwd[PATH_MAX];
if (getcwd(cwd, PATH_MAX) == NULL) {
perror("getcwd");
return;
}
int len = strlen(cwd);
if (strncmp(cwd, target, len) == 0)
target += len;
/* Assume pool/dataset is more likely */
strlcpy(*dataset, target, PATH_MAX);
int fd = open(target, O_RDONLY | O_CLOEXEC);
if (fd < 0)
return;
nvlist_t *cfg = NULL;
if (zpool_read_label(fd, &cfg, NULL) == 0) {
char *nm = NULL;
if (!nvlist_lookup_string(cfg, ZPOOL_CONFIG_POOL_NAME, &nm))
strlcpy(*dataset, nm, PATH_MAX);
nvlist_free(cfg);
}
if (close(fd))
perror("close");
}
/*
* 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: %s\n"),
dataset, strerror(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: %s\n"),
dataset, strerror(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[PATH_MAX], *pdataset = 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 '?':
if (optopt)
(void) fprintf(stderr,
gettext("Invalid option '%c'\n"), optopt);
(void) fprintf(stderr, gettext("Usage: mount.zfs "
"[-sfnvh] [-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);
}
parse_dataset(argv[0], &pdataset);
/* 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: %s\n"),
dataset, argv[1], strerror(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 (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);
}
if (!zfsutil || sloppy ||
libzfs_envvar_is_set("ZFS_MOUNT_HELPER")) {
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);
zfs_close(zhp);
libzfs_fini(g_zfs);
return (MOUNT_SYSERR);
}
/*
* 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);
zfs_close(zhp);
libzfs_fini(g_zfs);
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);
zfs_close(zhp);
libzfs_fini(g_zfs);
return (MOUNT_USAGE);
}
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 (!fake) {
if (zfsutil && !sloppy &&
!libzfs_envvar_is_set("ZFS_MOUNT_HELPER")) {
error = zfs_mount_at(zhp, mntopts, mntflags, mntpoint);
if (error) {
(void) fprintf(stderr, "zfs_mount_at() failed: "
"%s", libzfs_error_description(g_zfs));
zfs_close(zhp);
libzfs_fini(g_zfs);
return (MOUNT_SYSERR);
}
} else {
error = mount(dataset, mntpoint, MNTTYPE_ZFS,
mntflags, mntopts);
}
}
zfs_close(zhp);
libzfs_fini(g_zfs);
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);
}
#endif
fallthrough;
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);
}