[linux-2.6-block.git] / fs / ext2 / ioctl.c

/*
 * 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)
 */

#include "ext2.h"
#include <linux/capability.h>
#include <linux/time.h>
#include <linux/sched.h>
#include <linux/compat.h>
#include <linux/mount.h>
#include <linux/smp_lock.h>
#include <asm/current.h>
#include <asm/uaccess.h>


long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct ext2_inode_info *ei = EXT2_I(inode);
	unsigned int flags;
	unsigned short rsv_window_size;
	int ret;

	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);

	switch (cmd) {
	case EXT2_IOC_GETFLAGS:
		ext2_get_inode_flags(ei);
		flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
		return put_user(flags, (int __user *) arg);
	case EXT2_IOC_SETFLAGS: {
		unsigned int oldflags;

		ret = mnt_want_write(filp->f_path.mnt);
		if (ret)
			return ret;

		if (!is_owner_or_cap(inode)) {
			ret = -EACCES;
			goto setflags_out;
		}

		if (get_user(flags, (int __user *) arg)) {
			ret = -EFAULT;
			goto setflags_out;
		}

		flags = ext2_mask_flags(inode->i_mode, flags);

		mutex_lock(&inode->i_mutex);
		/* Is it quota file? Do not allow user to mess with it */
		if (IS_NOQUOTA(inode)) {
			mutex_unlock(&inode->i_mutex);
			ret = -EPERM;
			goto setflags_out;
		}
		oldflags = ei->i_flags;

		/*
		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
		 * the relevant capability.
		 *
		 * This test looks nicer. Thanks to Pauline Middelink
		 */
		if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
			if (!capable(CAP_LINUX_IMMUTABLE)) {
				mutex_unlock(&inode->i_mutex);
				ret = -EPERM;
				goto setflags_out;
			}
		}

		flags = flags & EXT2_FL_USER_MODIFIABLE;
		flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
		ei->i_flags = flags;
		mutex_unlock(&inode->i_mutex);

		ext2_set_inode_flags(inode);
		inode->i_ctime = CURRENT_TIME_SEC;
		mark_inode_dirty(inode);
setflags_out:
		mnt_drop_write(filp->f_path.mnt);
		return ret;
	}
	case EXT2_IOC_GETVERSION:
		return put_user(inode->i_generation, (int __user *) arg);
	case EXT2_IOC_SETVERSION:
		if (!is_owner_or_cap(inode))
			return -EPERM;
		ret = mnt_want_write(filp->f_path.mnt);
		if (ret)
			return ret;
		if (get_user(inode->i_generation, (int __user *) arg)) {
			ret = -EFAULT;
		} else {
			inode->i_ctime = CURRENT_TIME_SEC;
			mark_inode_dirty(inode);
		}
		mnt_drop_write(filp->f_path.mnt);
		return ret;
	case EXT2_IOC_GETRSVSZ:
		if (test_opt(inode->i_sb, RESERVATION)
			&& S_ISREG(inode->i_mode)
			&& ei->i_block_alloc_info) {
			rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
			return put_user(rsv_window_size, (int __user *)arg);
		}
		return -ENOTTY;
	case EXT2_IOC_SETRSVSZ: {

		if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
			return -ENOTTY;

		if (!is_owner_or_cap(inode))
			return -EACCES;

		if (get_user(rsv_window_size, (int __user *)arg))
			return -EFAULT;

		ret = mnt_want_write(filp->f_path.mnt);
		if (ret)
			return ret;

		if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
			rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;

		/*
		 * need to allocate reservation structure for this inode
		 * before set the window size
		 */
		/*
		 * XXX What lock should protect the rsv_goal_size?
		 * Accessed in ext2_get_block only.  ext3 uses i_truncate.
		 */
		mutex_lock(&ei->truncate_mutex);
		if (!ei->i_block_alloc_info)
			ext2_init_block_alloc_info(inode);

		if (ei->i_block_alloc_info){
			struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
			rsv->rsv_goal_size = rsv_window_size;
		}
		mutex_unlock(&ei->truncate_mutex);
		mnt_drop_write(filp->f_path.mnt);
		return 0;
	}
	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
	/* These are just misnamed, they actually get/put from/to user an int */
	switch (cmd) {
	case EXT2_IOC32_GETFLAGS:
		cmd = EXT2_IOC_GETFLAGS;
		break;
	case EXT2_IOC32_SETFLAGS:
		cmd = EXT2_IOC_SETFLAGS;
		break;
	case EXT2_IOC32_GETVERSION:
		cmd = EXT2_IOC_GETVERSION;
		break;
	case EXT2_IOC32_SETVERSION:
		cmd = EXT2_IOC_SETVERSION;
		break;
	default:
		return -ENOIOCTLCMD;
	}
	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
}
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/ext2/ioctl.c
	3	*
	4	* Copyright (C) 1993, 1994, 1995
	5	* Remy Card (card@masi.ibp.fr)
	6	* Laboratoire MASI - Institut Blaise Pascal
	7	* Universite Pierre et Marie Curie (Paris VI)
	8	*/
	9
	10	#include "ext2.h"
16f7e0fe	11	#include <linux/capability.h>
1da177e4 LT	12	#include <linux/time.h>
1da177e4 LT	13	#include <linux/sched.h>
e322ff07	14	#include <linux/compat.h>
42a74f20	15	#include <linux/mount.h>
e322ff07	16	#include <linux/smp_lock.h>
1da177e4 LT	17	#include <asm/current.h>
	18	#include <asm/uaccess.h>
	19
	20
14f9f7b2	21	long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
1da177e4	22	{
14f9f7b2	23	struct inode *inode = filp->f_dentry->d_inode;
1da177e4 LT	24	struct ext2_inode_info *ei = EXT2_I(inode);
1da177e4 LT	25	unsigned int flags;
a686cd89	26	unsigned short rsv_window_size;
42a74f20	27	int ret;
1da177e4 LT	28
	29	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
	30
	31	switch (cmd) {
	32	case EXT2_IOC_GETFLAGS:
4f99ed67	33	ext2_get_inode_flags(ei);
1da177e4 LT	34	flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
	35	return put_user(flags, (int __user *) arg);
	36	case EXT2_IOC_SETFLAGS: {
	37	unsigned int oldflags;
	38
42a74f20 DH	39	ret = mnt_want_write(filp->f_path.mnt);
	40	if (ret)
	41	return ret;
1da177e4	42
42a74f20 DH	43	if (!is_owner_or_cap(inode)) {
	44	ret = -EACCES;
	45	goto setflags_out;
	46	}
1da177e4	47
42a74f20 DH	48	if (get_user(flags, (int __user *) arg)) {
	49	ret = -EFAULT;
	50	goto setflags_out;
	51	}
1da177e4	52
ef8b6461	53	flags = ext2_mask_flags(inode->i_mode, flags);
1da177e4	54
93f210dd	55	mutex_lock(&inode->i_mutex);
e47776a0 JK	56	/* Is it quota file? Do not allow user to mess with it */
	57	if (IS_NOQUOTA(inode)) {
	58	mutex_unlock(&inode->i_mutex);
42a74f20 DH	59	ret = -EPERM;
42a74f20 DH	60	goto setflags_out;
e47776a0	61	}
1da177e4 LT	62	oldflags = ei->i_flags;
	63
	64	/*
	65	* The IMMUTABLE and APPEND_ONLY flags can only be changed by
	66	* the relevant capability.
	67	*
	68	* This test looks nicer. Thanks to Pauline Middelink
	69	*/
	70	if ((flags ^ oldflags) & (EXT2_APPEND_FL \| EXT2_IMMUTABLE_FL)) {
93f210dd AM	71	if (!capable(CAP_LINUX_IMMUTABLE)) {
93f210dd AM	72	mutex_unlock(&inode->i_mutex);
42a74f20 DH	73	ret = -EPERM;
42a74f20 DH	74	goto setflags_out;
93f210dd	75	}
1da177e4 LT	76	}
	77
	78	flags = flags & EXT2_FL_USER_MODIFIABLE;
	79	flags \|= oldflags & ~EXT2_FL_USER_MODIFIABLE;
	80	ei->i_flags = flags;
93f210dd	81	mutex_unlock(&inode->i_mutex);
1da177e4 LT	82
	83	ext2_set_inode_flags(inode);
	84	inode->i_ctime = CURRENT_TIME_SEC;
	85	mark_inode_dirty(inode);
42a74f20 DH	86	setflags_out:
	87	mnt_drop_write(filp->f_path.mnt);
	88	return ret;
1da177e4 LT	89	}
	90	case EXT2_IOC_GETVERSION:
	91	return put_user(inode->i_generation, (int __user *) arg);
	92	case EXT2_IOC_SETVERSION:
3bd858ab	93	if (!is_owner_or_cap(inode))
1da177e4	94	return -EPERM;
42a74f20 DH	95	ret = mnt_want_write(filp->f_path.mnt);
	96	if (ret)
	97	return ret;
	98	if (get_user(inode->i_generation, (int __user *) arg)) {
	99	ret = -EFAULT;
	100	} else {
	101	inode->i_ctime = CURRENT_TIME_SEC;
	102	mark_inode_dirty(inode);
	103	}
	104	mnt_drop_write(filp->f_path.mnt);
	105	return ret;
a686cd89 MB	106	case EXT2_IOC_GETRSVSZ:
	107	if (test_opt(inode->i_sb, RESERVATION)
	108	&& S_ISREG(inode->i_mode)
	109	&& ei->i_block_alloc_info) {
	110	rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
	111	return put_user(rsv_window_size, (int __user *)arg);
	112	}
	113	return -ENOTTY;
	114	case EXT2_IOC_SETRSVSZ: {
	115
	116	if (!test_opt(inode->i_sb, RESERVATION) \|\|!S_ISREG(inode->i_mode))
	117	return -ENOTTY;
	118
42a74f20	119	if (!is_owner_or_cap(inode))
a686cd89 MB	120	return -EACCES;
	121
	122	if (get_user(rsv_window_size, (int __user *)arg))
	123	return -EFAULT;
	124
42a74f20 DH	125	ret = mnt_want_write(filp->f_path.mnt);
	126	if (ret)
	127	return ret;
	128
a686cd89 MB	129	if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
	130	rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;
	131
	132	/*
	133	* need to allocate reservation structure for this inode
	134	* before set the window size
	135	*/
	136	/*
	137	* XXX What lock should protect the rsv_goal_size?
	138	* Accessed in ext2_get_block only. ext3 uses i_truncate.
	139	*/
	140	mutex_lock(&ei->truncate_mutex);
	141	if (!ei->i_block_alloc_info)
	142	ext2_init_block_alloc_info(inode);
	143
	144	if (ei->i_block_alloc_info){
	145	struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
	146	rsv->rsv_goal_size = rsv_window_size;
	147	}
	148	mutex_unlock(&ei->truncate_mutex);
42a74f20	149	mnt_drop_write(filp->f_path.mnt);
a686cd89 MB	150	return 0;
a686cd89 MB	151	}
1da177e4 LT	152	default:
	153	return -ENOTTY;
	154	}
	155	}
e322ff07 DH	156
	157	#ifdef CONFIG_COMPAT
	158	long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
	159	{
e322ff07 DH	160	/* These are just misnamed, they actually get/put from/to user an int */
	161	switch (cmd) {
	162	case EXT2_IOC32_GETFLAGS:
	163	cmd = EXT2_IOC_GETFLAGS;
	164	break;
	165	case EXT2_IOC32_SETFLAGS:
	166	cmd = EXT2_IOC_SETFLAGS;
	167	break;
	168	case EXT2_IOC32_GETVERSION:
	169	cmd = EXT2_IOC_GETVERSION;
	170	break;
	171	case EXT2_IOC32_SETVERSION:
	172	cmd = EXT2_IOC_SETVERSION;
	173	break;
	174	default:
	175	return -ENOIOCTLCMD;
	176	}
14f9f7b2	177	return ext2_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
e322ff07 DH	178	}
e322ff07 DH	179	#endif