[linux-block.git] / fs / hfsplus / ioctl.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;
	}
}
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/hfsplus/ioctl.c
	4	*
	5	* Copyright (C) 2003
	6	* Ethan Benson <erbenson@alaska.net>
	7	* partially derived from linux/fs/ext2/ioctl.c
	8	* Copyright (C) 1993, 1994, 1995
	9	* Remy Card (card@masi.ibp.fr)
	10	* Laboratoire MASI - Institut Blaise Pascal
	11	* Universite Pierre et Marie Curie (Paris VI)
	12	*
	13	* hfsplus ioctls
	14	*/
	15
16f7e0fe	16	#include <linux/capability.h>
1da177e4	17	#include <linux/fs.h>
42a74f20	18	#include <linux/mount.h>
1da177e4	19	#include <linux/sched.h>
7c0f6ba6	20	#include <linux/uaccess.h>
1da177e4 LT	21	#include "hfsplus_fs.h"
1da177e4 LT	22
a051f71c MG	23	/*
	24	* "Blessing" an HFS+ filesystem writes metadata to the superblock informing
	25	* the platform firmware which file to boot from
	26	*/
	27	static int hfsplus_ioctl_bless(struct file file, int __user user_flags)
	28	{
	29	struct dentry *dentry = file->f_path.dentry;
2b0143b5	30	struct inode *inode = d_inode(dentry);
a051f71c MG	31	struct hfsplus_sb_info *sbi = HFSPLUS_SB(inode->i_sb);
	32	struct hfsplus_vh *vh = sbi->s_vhdr;
	33	struct hfsplus_vh *bvh = sbi->s_backup_vhdr;
7dea9665	34	u32 cnid = (unsigned long)dentry->d_fsdata;
a051f71c MG	35
	36	if (!capable(CAP_SYS_ADMIN))
	37	return -EPERM;
	38
	39	mutex_lock(&sbi->vh_mutex);
	40
	41	/* Directory containing the bootable system */
	42	vh->finder_info[0] = bvh->finder_info[0] =
	43	cpu_to_be32(parent_ino(dentry));
	44
7dea9665 MG	45	/*
	46	* Bootloader. Just using the inode here breaks in the case of
	47	* hard links - the firmware wants the ID of the hard link file,
	48	* but the inode points at the indirect inode
	49	*/
	50	vh->finder_info[1] = bvh->finder_info[1] = cpu_to_be32(cnid);
a051f71c MG	51
	52	/* Per spec, the OS X system folder - same as finder_info[0] here */
	53	vh->finder_info[5] = bvh->finder_info[5] =
	54	cpu_to_be32(parent_ino(dentry));
	55
	56	mutex_unlock(&sbi->vh_mutex);
	57	return 0;
	58	}
	59
94744567 CH	60	long hfsplus_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	61	{
	62	void __user argp = (void __user )arg;
	63
	64	switch (cmd) {
a051f71c MG	65	case HFSPLUS_IOC_BLESS:
a051f71c MG	66	return hfsplus_ioctl_bless(file, argp);
1da177e4 LT	67	default:
	68	return -ENOTTY;
	69	}
	70	}