Merge master.kernel.org:/home/rmk/linux-2.6-mmc
[linux-2.6] / fs / ext3 / ioctl.c
1 /*
2  * linux/fs/ext3/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 <linux/fs.h>
11 #include <linux/jbd.h>
12 #include <linux/capability.h>
13 #include <linux/ext3_fs.h>
14 #include <linux/ext3_jbd.h>
15 #include <linux/time.h>
16 #include <asm/uaccess.h>
17
18
19 int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
20                 unsigned long arg)
21 {
22         struct ext3_inode_info *ei = EXT3_I(inode);
23         unsigned int flags;
24         unsigned short rsv_window_size;
25
26         ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
27
28         switch (cmd) {
29         case EXT3_IOC_GETFLAGS:
30                 flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
31                 return put_user(flags, (int __user *) arg);
32         case EXT3_IOC_SETFLAGS: {
33                 handle_t *handle = NULL;
34                 int err;
35                 struct ext3_iloc iloc;
36                 unsigned int oldflags;
37                 unsigned int jflag;
38
39                 if (IS_RDONLY(inode))
40                         return -EROFS;
41
42                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
43                         return -EACCES;
44
45                 if (get_user(flags, (int __user *) arg))
46                         return -EFAULT;
47
48                 if (!S_ISDIR(inode->i_mode))
49                         flags &= ~EXT3_DIRSYNC_FL;
50
51                 mutex_lock(&inode->i_mutex);
52                 oldflags = ei->i_flags;
53
54                 /* The JOURNAL_DATA flag is modifiable only by root */
55                 jflag = flags & EXT3_JOURNAL_DATA_FL;
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) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) {
64                         if (!capable(CAP_LINUX_IMMUTABLE)) {
65                                 mutex_unlock(&inode->i_mutex);
66                                 return -EPERM;
67                         }
68                 }
69
70                 /*
71                  * The JOURNAL_DATA flag can only be changed by
72                  * the relevant capability.
73                  */
74                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
75                         if (!capable(CAP_SYS_RESOURCE)) {
76                                 mutex_unlock(&inode->i_mutex);
77                                 return -EPERM;
78                         }
79                 }
80
81
82                 handle = ext3_journal_start(inode, 1);
83                 if (IS_ERR(handle)) {
84                         mutex_unlock(&inode->i_mutex);
85                         return PTR_ERR(handle);
86                 }
87                 if (IS_SYNC(inode))
88                         handle->h_sync = 1;
89                 err = ext3_reserve_inode_write(handle, inode, &iloc);
90                 if (err)
91                         goto flags_err;
92
93                 flags = flags & EXT3_FL_USER_MODIFIABLE;
94                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
95                 ei->i_flags = flags;
96
97                 ext3_set_inode_flags(inode);
98                 inode->i_ctime = CURRENT_TIME_SEC;
99
100                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
101 flags_err:
102                 ext3_journal_stop(handle);
103                 if (err) {
104                         mutex_unlock(&inode->i_mutex);
105                         return err;
106                 }
107
108                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
109                         err = ext3_change_inode_journal_flag(inode, jflag);
110                 mutex_unlock(&inode->i_mutex);
111                 return err;
112         }
113         case EXT3_IOC_GETVERSION:
114         case EXT3_IOC_GETVERSION_OLD:
115                 return put_user(inode->i_generation, (int __user *) arg);
116         case EXT3_IOC_SETVERSION:
117         case EXT3_IOC_SETVERSION_OLD: {
118                 handle_t *handle;
119                 struct ext3_iloc iloc;
120                 __u32 generation;
121                 int err;
122
123                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
124                         return -EPERM;
125                 if (IS_RDONLY(inode))
126                         return -EROFS;
127                 if (get_user(generation, (int __user *) arg))
128                         return -EFAULT;
129
130                 handle = ext3_journal_start(inode, 1);
131                 if (IS_ERR(handle))
132                         return PTR_ERR(handle);
133                 err = ext3_reserve_inode_write(handle, inode, &iloc);
134                 if (err == 0) {
135                         inode->i_ctime = CURRENT_TIME_SEC;
136                         inode->i_generation = generation;
137                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
138                 }
139                 ext3_journal_stop(handle);
140                 return err;
141         }
142 #ifdef CONFIG_JBD_DEBUG
143         case EXT3_IOC_WAIT_FOR_READONLY:
144                 /*
145                  * This is racy - by the time we're woken up and running,
146                  * the superblock could be released.  And the module could
147                  * have been unloaded.  So sue me.
148                  *
149                  * Returns 1 if it slept, else zero.
150                  */
151                 {
152                         struct super_block *sb = inode->i_sb;
153                         DECLARE_WAITQUEUE(wait, current);
154                         int ret = 0;
155
156                         set_current_state(TASK_INTERRUPTIBLE);
157                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
158                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
159                                 schedule();
160                                 ret = 1;
161                         }
162                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
163                         return ret;
164                 }
165 #endif
166         case EXT3_IOC_GETRSVSZ:
167                 if (test_opt(inode->i_sb, RESERVATION)
168                         && S_ISREG(inode->i_mode)
169                         && ei->i_block_alloc_info) {
170                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
171                         return put_user(rsv_window_size, (int __user *)arg);
172                 }
173                 return -ENOTTY;
174         case EXT3_IOC_SETRSVSZ: {
175
176                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
177                         return -ENOTTY;
178
179                 if (IS_RDONLY(inode))
180                         return -EROFS;
181
182                 if ((current->fsuid != inode->i_uid) && !capable(CAP_FOWNER))
183                         return -EACCES;
184
185                 if (get_user(rsv_window_size, (int __user *)arg))
186                         return -EFAULT;
187
188                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
189                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
190
191                 /*
192                  * need to allocate reservation structure for this inode
193                  * before set the window size
194                  */
195                 mutex_lock(&ei->truncate_mutex);
196                 if (!ei->i_block_alloc_info)
197                         ext3_init_block_alloc_info(inode);
198
199                 if (ei->i_block_alloc_info){
200                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
201                         rsv->rsv_goal_size = rsv_window_size;
202                 }
203                 mutex_unlock(&ei->truncate_mutex);
204                 return 0;
205         }
206         case EXT3_IOC_GROUP_EXTEND: {
207                 unsigned long n_blocks_count;
208                 struct super_block *sb = inode->i_sb;
209                 int err;
210
211                 if (!capable(CAP_SYS_RESOURCE))
212                         return -EPERM;
213
214                 if (IS_RDONLY(inode))
215                         return -EROFS;
216
217                 if (get_user(n_blocks_count, (__u32 __user *)arg))
218                         return -EFAULT;
219
220                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
221                 journal_lock_updates(EXT3_SB(sb)->s_journal);
222                 journal_flush(EXT3_SB(sb)->s_journal);
223                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
224
225                 return err;
226         }
227         case EXT3_IOC_GROUP_ADD: {
228                 struct ext3_new_group_data input;
229                 struct super_block *sb = inode->i_sb;
230                 int err;
231
232                 if (!capable(CAP_SYS_RESOURCE))
233                         return -EPERM;
234
235                 if (IS_RDONLY(inode))
236                         return -EROFS;
237
238                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
239                                 sizeof(input)))
240                         return -EFAULT;
241
242                 err = ext3_group_add(sb, &input);
243                 journal_lock_updates(EXT3_SB(sb)->s_journal);
244                 journal_flush(EXT3_SB(sb)->s_journal);
245                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
246
247                 return err;
248         }
249
250
251         default:
252                 return -ENOTTY;
253         }
254 }