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"
11#include <linux/capability.h>
12#include <linux/time.h>
13#include <linux/sched.h>
14#include <linux/compat.h>
15#include <linux/smp_lock.h>
16#include <asm/current.h>
17#include <asm/uaccess.h>
18
19
20int ext2_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
21		unsigned long arg)
22{
23	struct ext2_inode_info *ei = EXT2_I(inode);
24	unsigned int flags;
25
26	ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
27
28	switch (cmd) {
29	case EXT2_IOC_GETFLAGS:
30		ext2_get_inode_flags(ei);
31		flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
32		return put_user(flags, (int __user *) arg);
33	case EXT2_IOC_SETFLAGS: {
34		unsigned int oldflags;
35
36		if (IS_RDONLY(inode))
37			return -EROFS;
38
39		if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
40			return -EACCES;
41
42		if (get_user(flags, (int __user *) arg))
43			return -EFAULT;
44
45		if (!S_ISDIR(inode->i_mode))
46			flags &= ~EXT2_DIRSYNC_FL;
47
48		mutex_lock(&inode->i_mutex);
49		oldflags = ei->i_flags;
50
51		/*
52		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
53		 * the relevant capability.
54		 *
55		 * This test looks nicer. Thanks to Pauline Middelink
56		 */
57		if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
58			if (!capable(CAP_LINUX_IMMUTABLE)) {
59				mutex_unlock(&inode->i_mutex);
60				return -EPERM;
61			}
62		}
63
64		flags = flags & EXT2_FL_USER_MODIFIABLE;
65		flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
66		ei->i_flags = flags;
67		mutex_unlock(&inode->i_mutex);
68
69		ext2_set_inode_flags(inode);
70		inode->i_ctime = CURRENT_TIME_SEC;
71		mark_inode_dirty(inode);
72		return 0;
73	}
74	case EXT2_IOC_GETVERSION:
75		return put_user(inode->i_generation, (int __user *) arg);
76	case EXT2_IOC_SETVERSION:
77		if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
78			return -EPERM;
79		if (IS_RDONLY(inode))
80			return -EROFS;
81		if (get_user(inode->i_generation, (int __user *) arg))
82			return -EFAULT;
83		inode->i_ctime = CURRENT_TIME_SEC;
84		mark_inode_dirty(inode);
85		return 0;
86	default:
87		return -ENOTTY;
88	}
89}
90
91#ifdef CONFIG_COMPAT
92long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
93{
94	struct inode *inode = file->f_path.dentry->d_inode;
95	int ret;
96
97	/* These are just misnamed, they actually get/put from/to user an int */
98	switch (cmd) {
99	case EXT2_IOC32_GETFLAGS:
100		cmd = EXT2_IOC_GETFLAGS;
101		break;
102	case EXT2_IOC32_SETFLAGS:
103		cmd = EXT2_IOC_SETFLAGS;
104		break;
105	case EXT2_IOC32_GETVERSION:
106		cmd = EXT2_IOC_GETVERSION;
107		break;
108	case EXT2_IOC32_SETVERSION:
109		cmd = EXT2_IOC_SETVERSION;
110		break;
111	default:
112		return -ENOIOCTLCMD;
113	}
114	lock_kernel();
115	ret = ext2_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
116	unlock_kernel();
117	return ret;
118}
119#endif
120