Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6.git
[linux-2.6] / fs / ext2 / ioctl.c
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
20 int 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         unsigned short rsv_window_size;
26
27         ext2_debug ("cmd = %u, arg = %lu\n", cmd, arg);
28
29         switch (cmd) {
30         case EXT2_IOC_GETFLAGS:
31                 ext2_get_inode_flags(ei);
32                 flags = ei->i_flags & EXT2_FL_USER_VISIBLE;
33                 return put_user(flags, (int __user *) arg);
34         case EXT2_IOC_SETFLAGS: {
35                 unsigned int oldflags;
36
37                 if (IS_RDONLY(inode))
38                         return -EROFS;
39
40                 if (!is_owner_or_cap(inode))
41                         return -EACCES;
42
43                 if (get_user(flags, (int __user *) arg))
44                         return -EFAULT;
45
46                 if (!S_ISDIR(inode->i_mode))
47                         flags &= ~EXT2_DIRSYNC_FL;
48
49                 mutex_lock(&inode->i_mutex);
50                 /* Is it quota file? Do not allow user to mess with it */
51                 if (IS_NOQUOTA(inode)) {
52                         mutex_unlock(&inode->i_mutex);
53                         return -EPERM;
54                 }
55                 oldflags = ei->i_flags;
56
57                 /*
58                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
59                  * the relevant capability.
60                  *
61                  * This test looks nicer. Thanks to Pauline Middelink
62                  */
63                 if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) {
64                         if (!capable(CAP_LINUX_IMMUTABLE)) {
65                                 mutex_unlock(&inode->i_mutex);
66                                 return -EPERM;
67                         }
68                 }
69
70                 flags = flags & EXT2_FL_USER_MODIFIABLE;
71                 flags |= oldflags & ~EXT2_FL_USER_MODIFIABLE;
72                 ei->i_flags = flags;
73                 mutex_unlock(&inode->i_mutex);
74
75                 ext2_set_inode_flags(inode);
76                 inode->i_ctime = CURRENT_TIME_SEC;
77                 mark_inode_dirty(inode);
78                 return 0;
79         }
80         case EXT2_IOC_GETVERSION:
81                 return put_user(inode->i_generation, (int __user *) arg);
82         case EXT2_IOC_SETVERSION:
83                 if (!is_owner_or_cap(inode))
84                         return -EPERM;
85                 if (IS_RDONLY(inode))
86                         return -EROFS;
87                 if (get_user(inode->i_generation, (int __user *) arg))
88                         return -EFAULT; 
89                 inode->i_ctime = CURRENT_TIME_SEC;
90                 mark_inode_dirty(inode);
91                 return 0;
92         case EXT2_IOC_GETRSVSZ:
93                 if (test_opt(inode->i_sb, RESERVATION)
94                         && S_ISREG(inode->i_mode)
95                         && ei->i_block_alloc_info) {
96                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
97                         return put_user(rsv_window_size, (int __user *)arg);
98                 }
99                 return -ENOTTY;
100         case EXT2_IOC_SETRSVSZ: {
101
102                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
103                         return -ENOTTY;
104
105                 if (IS_RDONLY(inode))
106                         return -EROFS;
107
108                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
109                         return -EACCES;
110
111                 if (get_user(rsv_window_size, (int __user *)arg))
112                         return -EFAULT;
113
114                 if (rsv_window_size > EXT2_MAX_RESERVE_BLOCKS)
115                         rsv_window_size = EXT2_MAX_RESERVE_BLOCKS;
116
117                 /*
118                  * need to allocate reservation structure for this inode
119                  * before set the window size
120                  */
121                 /*
122                  * XXX What lock should protect the rsv_goal_size?
123                  * Accessed in ext2_get_block only.  ext3 uses i_truncate.
124                  */
125                 mutex_lock(&ei->truncate_mutex);
126                 if (!ei->i_block_alloc_info)
127                         ext2_init_block_alloc_info(inode);
128
129                 if (ei->i_block_alloc_info){
130                         struct ext2_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
131                         rsv->rsv_goal_size = rsv_window_size;
132                 }
133                 mutex_unlock(&ei->truncate_mutex);
134                 return 0;
135         }
136         default:
137                 return -ENOTTY;
138         }
139 }
140
141 #ifdef CONFIG_COMPAT
142 long ext2_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
143 {
144         struct inode *inode = file->f_path.dentry->d_inode;
145         int ret;
146
147         /* These are just misnamed, they actually get/put from/to user an int */
148         switch (cmd) {
149         case EXT2_IOC32_GETFLAGS:
150                 cmd = EXT2_IOC_GETFLAGS;
151                 break;
152         case EXT2_IOC32_SETFLAGS:
153                 cmd = EXT2_IOC_SETFLAGS;
154                 break;
155         case EXT2_IOC32_GETVERSION:
156                 cmd = EXT2_IOC_GETVERSION;
157                 break;
158         case EXT2_IOC32_SETVERSION:
159                 cmd = EXT2_IOC_SETVERSION;
160                 break;
161         default:
162                 return -ENOIOCTLCMD;
163         }
164         lock_kernel();
165         ret = ext2_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
166         unlock_kernel();
167         return ret;
168 }
169 #endif