freebsd-dev/cmd/zvol_id/zvol_id_main.c
Fajar A. Nugraha a5729f7b22 Fixes to enable zvol symlink creation
This commit fixes issue on
https://github.com/behlendorf/zfs/issues/#issue/172
Changes:
- update BLKZNAME to use _IOR instead of _IO.  Kernel 2.6.32 allows
read parameters (copy_to_user) with _IO, while newer kernels (tested
Archlinux's 2.6.37 kernel) enforces _IOR (which is correct)
- fix return code and message on error

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
2011-03-24 11:48:18 -07:00

94 lines
2.3 KiB
C

/*
* 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) 2011, Fajar A. Nugraha. All rights reserved.
* Use is subject to license terms.
*/
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <linux/ioctl.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/zfs_znode.h>
#include <sys/fs/zfs.h>
int ioctl_get_msg(char *var, int fd)
{
int error = 0;
char msg[ZFS_MAXNAMELEN];
error = ioctl(fd, BLKZNAME, msg);
if (error < 0) {
return (error);
}
snprintf(var, ZFS_MAXNAMELEN, "%s", msg);
return (error);
}
int main(int argc, char **argv)
{
int fd, error = 0;
char zvol_name[ZFS_MAXNAMELEN], zvol_name_part[ZFS_MAXNAMELEN];
char *dev_name;
struct stat64 statbuf;
int dev_minor, dev_part;
if (argc < 2) {
printf("Usage: %s /dev/zvol_device_node\n", argv[0]);
return (EINVAL);
}
dev_name = argv[1];
error = stat64(dev_name, &statbuf);
if (error != 0) {
printf("Unable to access device file: %s\n", dev_name);
return (errno);
}
dev_minor = minor(statbuf.st_rdev);
dev_part = dev_minor % ZVOL_MINORS;
fd = open(dev_name, O_RDONLY);
if (fd < 0) {
printf("Unable to open device file: %s\n", dev_name);
return (errno);
}
error = ioctl_get_msg(zvol_name, fd);
if (error < 0) {
printf("ioctl_get_msg failed:%s\n", strerror(errno));
return (errno);
}
if (dev_part > 0)
snprintf(zvol_name_part, ZFS_MAXNAMELEN, "%s-part%d", zvol_name,
dev_part);
else
snprintf(zvol_name_part, ZFS_MAXNAMELEN, "%s", zvol_name);
printf("%s\n", zvol_name_part);
close(fd);
return (error);
}