aboutsummaryrefslogtreecommitdiff
path: root/fs/jfs/ioctl.c
blob: f19d1e04a374b39e9dc97779f9539d5598f032dd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
/*
 * linux/fs/jfs/ioctl.c
 *
 * Copyright (C) 2006 Herbert Poetzl
 * adapted from Remy Card's ext2/ioctl.c
 */

#include <linux/fs.h>
#include <linux/ctype.h>
#include <linux/capability.h>
#include <linux/mount.h>
#include <linux/time.h>
#include <linux/sched.h>
#include <asm/current.h>
#include <asm/uaccess.h>

#include "jfs_incore.h"
#include "jfs_dinode.h"
#include "jfs_inode.h"


static struct {
	long jfs_flag;
	long ext2_flag;
} jfs_map[] = {
	{JFS_NOATIME_FL,	FS_NOATIME_FL},
	{JFS_DIRSYNC_FL,	FS_DIRSYNC_FL},
	{JFS_SYNC_FL,		FS_SYNC_FL},
	{JFS_SECRM_FL,		FS_SECRM_FL},
	{JFS_UNRM_FL,		FS_UNRM_FL},
	{JFS_APPEND_FL,		FS_APPEND_FL},
	{JFS_IMMUTABLE_FL,	FS_IMMUTABLE_FL},
	{0, 0},
};

static long jfs_map_ext2(unsigned long flags, int from)
{
	int index=0;
	long mapped=0;

	while (jfs_map[index].jfs_flag) {
		if (from) {
			if (jfs_map[index].ext2_flag & flags)
				mapped |= jfs_map[index].jfs_flag;
		} else {
			if (jfs_map[index].jfs_flag & flags)
				mapped |= jfs_map[index].ext2_flag;
		}
		index++;
	}
	return mapped;
}


long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct inode *inode = filp->f_dentry->d_inode;
	struct jfs_inode_info *jfs_inode = JFS_IP(inode);
	unsigned int flags;

	switch (cmd) {
	case JFS_IOC_GETFLAGS:
		jfs_get_inode_flags(jfs_inode);
		flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;
		flags = jfs_map_ext2(flags, 0);
		return put_user(flags, (int __user *) arg);
	case JFS_IOC_SETFLAGS: {
		unsigned int oldflags;
		int err;

		err = mnt_want_write_file(filp);
		if (err)
			return err;

		if (!inode_owner_or_capable(inode)) {
			err = -EACCES;
			goto setflags_out;
		}
		if (get_user(flags, (int __user *) arg)) {
			err = -EFAULT;
			goto setflags_out;
		}

		flags = jfs_map_ext2(flags, 1);
		if (!S_ISDIR(inode->i_mode))
			flags &= ~JFS_DIRSYNC_FL;

		/* Is it quota file? Do not allow user to mess with it */
		if (IS_NOQUOTA(inode)) {
			err = -EPERM;
			goto setflags_out;
		}

		/* Lock against other parallel changes of flags */
		mutex_lock(&inode->i_mutex);

		jfs_get_inode_flags(jfs_inode);
		oldflags = jfs_inode->mode2;

		/*
		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
		 * the relevant capability.
		 */
		if ((oldflags & JFS_IMMUTABLE_FL) ||
			((flags ^ oldflags) &
			(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
			if (!capable(CAP_LINUX_IMMUTABLE)) {
				mutex_unlock(&inode->i_mutex);
				err = -EPERM;
				goto setflags_out;
			}
		}

		flags = flags & JFS_FL_USER_MODIFIABLE;
		flags |= oldflags & ~JFS_FL_USER_MODIFIABLE;
		jfs_inode->mode2 = flags;

		jfs_set_inode_flags(inode);
		mutex_unlock(&inode->i_mutex);
		inode->i_ctime = CURRENT_TIME_SEC;
		mark_inode_dirty(inode);
setflags_out:
		mnt_drop_write_file(filp);
		return err;
	}
	default:
		return -ENOTTY;
	}
}

#ifdef CONFIG_COMPAT
long jfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	/* While these ioctl numbers defined with 'long' and have different
	 * numbers than the 64bit ABI,
	 * the actual implementation only deals with ints and is compatible.
	 */
	switch (cmd) {
	case JFS_IOC_GETFLAGS32:
		cmd = JFS_IOC_GETFLAGS;
		break;
	case JFS_IOC_SETFLAGS32:
		cmd = JFS_IOC_SETFLAGS;
		break;
	}
	return jfs_ioctl(filp, cmd, arg);
}
#endif