btrfs-progs/props.c
Alexander Block 85be2aaf91 Btrfs-progs: introduce btrfs property subgroup
"btrfs filesystem property" is a generic interface to set/get
properties on filesystem objects (inodes/subvolumes/filesystems
/devs).

This patch adds the generic framework for properties and also
implements two properties. The first is the read-only property
for subvolumes and the second is the label property for devices.

Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: David Sterba <dsterba@suse.cz>
Signed-off-by: Chris Mason <clm@fb.com>
2014-01-31 08:22:31 -08:00

111 lines
2.5 KiB
C

/*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <unistd.h>
#include "ctree.h"
#include "commands.h"
#include "utils.h"
#include "props.h"
static int prop_read_only(enum prop_object_type type,
const char *object,
const char *name,
const char *value)
{
int ret = 0;
int fd = -1;
u64 flags = 0;
fd = open(object, O_RDONLY);
if (fd < 0) {
ret = -errno;
fprintf(stderr, "ERROR: open %s failed. %s\n",
object, strerror(-ret));
goto out;
}
ret = ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags);
if (ret < 0) {
ret = -errno;
fprintf(stderr, "ERROR: failed to get flags for %s. %s\n",
object, strerror(-ret));
goto out;
}
if (!value) {
if (flags & BTRFS_SUBVOL_RDONLY)
fprintf(stdout, "ro=true\n");
else
fprintf(stdout, "ro=false\n");
ret = 0;
goto out;
}
if (!strcmp(value, "true")) {
flags |= BTRFS_SUBVOL_RDONLY;
} else if (!strcmp(value, "false")) {
flags = flags & ~BTRFS_SUBVOL_RDONLY;
} else {
ret = -EINVAL;
fprintf(stderr, "ERROR: invalid value for property.\n");
goto out;
}
ret = ioctl(fd, BTRFS_IOC_SUBVOL_SETFLAGS, &flags);
if (ret < 0) {
ret = -errno;
fprintf(stderr, "ERROR: failed to set flags for %s. %s\n",
object, strerror(-ret));
goto out;
}
out:
if (fd != -1)
close(fd);
return ret;
}
static int prop_label(enum prop_object_type type,
const char *object,
const char *name,
const char *value)
{
int ret;
if (value) {
ret = set_label((char *) object, (char *) value);
} else {
char label[BTRFS_LABEL_SIZE];
ret = get_label((char *) object, label);
if (!ret)
fprintf(stdout, "label=%s\n", label);
}
return ret;
}
const struct prop_handler prop_handlers[] = {
{"ro", "Set/get read-only flag of subvolume.", 0, prop_object_subvol,
prop_read_only},
{"label", "Set/get label of device.", 0, prop_object_dev, prop_label},
{0, 0, 0, 0, 0}
};