xref: /openbmc/linux/fs/jfs/ioctl.c (revision f42b3800)
1 /*
2  * linux/fs/jfs/ioctl.c
3  *
4  * Copyright (C) 2006 Herbert Poetzl
5  * adapted from Remy Card's ext2/ioctl.c
6  */
7 
8 #include <linux/fs.h>
9 #include <linux/ctype.h>
10 #include <linux/capability.h>
11 #include <linux/time.h>
12 #include <linux/sched.h>
13 #include <asm/current.h>
14 #include <asm/uaccess.h>
15 
16 #include "jfs_incore.h"
17 #include "jfs_dinode.h"
18 #include "jfs_inode.h"
19 
20 
21 static struct {
22 	long jfs_flag;
23 	long ext2_flag;
24 } jfs_map[] = {
25 	{JFS_NOATIME_FL,	FS_NOATIME_FL},
26 	{JFS_DIRSYNC_FL,	FS_DIRSYNC_FL},
27 	{JFS_SYNC_FL,		FS_SYNC_FL},
28 	{JFS_SECRM_FL,		FS_SECRM_FL},
29 	{JFS_UNRM_FL,		FS_UNRM_FL},
30 	{JFS_APPEND_FL,		FS_APPEND_FL},
31 	{JFS_IMMUTABLE_FL,	FS_IMMUTABLE_FL},
32 	{0, 0},
33 };
34 
35 static long jfs_map_ext2(unsigned long flags, int from)
36 {
37 	int index=0;
38 	long mapped=0;
39 
40 	while (jfs_map[index].jfs_flag) {
41 		if (from) {
42 			if (jfs_map[index].ext2_flag & flags)
43 				mapped |= jfs_map[index].jfs_flag;
44 		} else {
45 			if (jfs_map[index].jfs_flag & flags)
46 				mapped |= jfs_map[index].ext2_flag;
47 		}
48 		index++;
49 	}
50 	return mapped;
51 }
52 
53 
54 long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
55 {
56 	struct inode *inode = filp->f_dentry->d_inode;
57 	struct jfs_inode_info *jfs_inode = JFS_IP(inode);
58 	unsigned int flags;
59 
60 	switch (cmd) {
61 	case JFS_IOC_GETFLAGS:
62 		jfs_get_inode_flags(jfs_inode);
63 		flags = jfs_inode->mode2 & JFS_FL_USER_VISIBLE;
64 		flags = jfs_map_ext2(flags, 0);
65 		return put_user(flags, (int __user *) arg);
66 	case JFS_IOC_SETFLAGS: {
67 		unsigned int oldflags;
68 
69 		if (IS_RDONLY(inode))
70 			return -EROFS;
71 
72 		if (!is_owner_or_cap(inode))
73 			return -EACCES;
74 
75 		if (get_user(flags, (int __user *) arg))
76 			return -EFAULT;
77 
78 		flags = jfs_map_ext2(flags, 1);
79 		if (!S_ISDIR(inode->i_mode))
80 			flags &= ~JFS_DIRSYNC_FL;
81 
82 		/* Is it quota file? Do not allow user to mess with it */
83 		if (IS_NOQUOTA(inode))
84 			return -EPERM;
85 
86 		/* Lock against other parallel changes of flags */
87 		mutex_lock(&inode->i_mutex);
88 
89 		jfs_get_inode_flags(jfs_inode);
90 		oldflags = jfs_inode->mode2;
91 
92 		/*
93 		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
94 		 * the relevant capability.
95 		 */
96 		if ((oldflags & JFS_IMMUTABLE_FL) ||
97 			((flags ^ oldflags) &
98 			(JFS_APPEND_FL | JFS_IMMUTABLE_FL))) {
99 			if (!capable(CAP_LINUX_IMMUTABLE)) {
100 				mutex_unlock(&inode->i_mutex);
101 				return -EPERM;
102 			}
103 		}
104 
105 		flags = flags & JFS_FL_USER_MODIFIABLE;
106 		flags |= oldflags & ~JFS_FL_USER_MODIFIABLE;
107 		jfs_inode->mode2 = flags;
108 
109 		jfs_set_inode_flags(inode);
110 		mutex_unlock(&inode->i_mutex);
111 		inode->i_ctime = CURRENT_TIME_SEC;
112 		mark_inode_dirty(inode);
113 		return 0;
114 	}
115 	default:
116 		return -ENOTTY;
117 	}
118 }
119 
120 #ifdef CONFIG_COMPAT
121 long jfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
122 {
123 	/* While these ioctl numbers defined with 'long' and have different
124 	 * numbers than the 64bit ABI,
125 	 * the actual implementation only deals with ints and is compatible.
126 	 */
127 	switch (cmd) {
128 	case JFS_IOC_GETFLAGS32:
129 		cmd = JFS_IOC_GETFLAGS;
130 		break;
131 	case JFS_IOC_SETFLAGS32:
132 		cmd = JFS_IOC_SETFLAGS;
133 		break;
134 	}
135 	return jfs_ioctl(filp, cmd, arg);
136 }
137 #endif
138