linux/fs/hfsplus/ioctl.c

71 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/hfsplus/ioctl.c
*
* Copyright (C) 2003
* Ethan Benson <erbenson@alaska.net>
* partially derived from linux/fs/ext2/ioctl.c
* Copyright (C) 1993, 1994, 1995
* Remy Card (card@masi.ibp.fr)
* Laboratoire MASI - Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* hfsplus ioctls
*/
#include <linux/capability.h>
#include <linux/fs.h>
#include <linux/mount.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include "hfsplus_fs.h"
/*
* "Blessing" an HFS+ filesystem writes metadata to the superblock informing
* the platform firmware which file to boot from
*/
static int hfsplus_ioctl_bless(struct file *file, int __user *user_flags)
{
struct dentry *dentry = file->f_path.dentry;
struct inode *inode = d_inode(dentry);
struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
struct hfsplus_vh *vh = sbi->s_vhdr;
struct hfsplus_vh *bvh = sbi->s_backup_vhdr;
u32 cnid = (unsigned long)dentry->d_fsdata;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
mutex_lock(&sbi->vh_mutex);
/* Directory containing the bootable system */
vh->finder_info[0] = bvh->finder_info[0] =
cpu_to_be32(parent_ino(dentry));
/*
* Bootloader. Just using the inode here breaks in the case of
* hard links - the firmware wants the ID of the hard link file,
* but the inode points at the indirect inode
*/
vh->finder_info[1] = bvh->finder_info[1] = cpu_to_be32(cnid);
/* Per spec, the OS X system folder - same as finder_info[0] here */
vh->finder_info[5] = bvh->finder_info[5] =
cpu_to_be32(parent_ino(dentry));
mutex_unlock(&sbi->vh_mutex);
return 0;
}
long hfsplus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
switch (cmd) {
case HFSPLUS_IOC_BLESS:
return hfsplus_ioctl_bless(file, argp);
default:
return -ENOTTY;
}
}