[PATCH] new helper - inotify_clone_watch()
[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 <linux/compat.h>
17 #include <linux/smp_lock.h>
18 #include <asm/uaccess.h>
19
20 int ext3_ioctl (struct inode * inode, struct file * filp, unsigned int cmd,
21                 unsigned long arg)
22 {
23         struct ext3_inode_info *ei = EXT3_I(inode);
24         unsigned int flags;
25         unsigned short rsv_window_size;
26
27         ext3_debug ("cmd = %u, arg = %lu\n", cmd, arg);
28
29         switch (cmd) {
30         case EXT3_IOC_GETFLAGS:
31                 ext3_get_inode_flags(ei);
32                 flags = ei->i_flags & EXT3_FL_USER_VISIBLE;
33                 return put_user(flags, (int __user *) arg);
34         case EXT3_IOC_SETFLAGS: {
35                 handle_t *handle = NULL;
36                 int err;
37                 struct ext3_iloc iloc;
38                 unsigned int oldflags;
39                 unsigned int jflag;
40
41                 if (IS_RDONLY(inode))
42                         return -EROFS;
43
44                 if (!is_owner_or_cap(inode))
45                         return -EACCES;
46
47                 if (get_user(flags, (int __user *) arg))
48                         return -EFAULT;
49
50                 if (!S_ISDIR(inode->i_mode))
51                         flags &= ~EXT3_DIRSYNC_FL;
52
53                 mutex_lock(&inode->i_mutex);
54                 oldflags = ei->i_flags;
55
56                 /* The JOURNAL_DATA flag is modifiable only by root */
57                 jflag = flags & EXT3_JOURNAL_DATA_FL;
58
59                 /*
60                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
61                  * the relevant capability.
62                  *
63                  * This test looks nicer. Thanks to Pauline Middelink
64                  */
65                 if ((flags ^ oldflags) & (EXT3_APPEND_FL | EXT3_IMMUTABLE_FL)) {
66                         if (!capable(CAP_LINUX_IMMUTABLE)) {
67                                 mutex_unlock(&inode->i_mutex);
68                                 return -EPERM;
69                         }
70                 }
71
72                 /*
73                  * The JOURNAL_DATA flag can only be changed by
74                  * the relevant capability.
75                  */
76                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL)) {
77                         if (!capable(CAP_SYS_RESOURCE)) {
78                                 mutex_unlock(&inode->i_mutex);
79                                 return -EPERM;
80                         }
81                 }
82
83
84                 handle = ext3_journal_start(inode, 1);
85                 if (IS_ERR(handle)) {
86                         mutex_unlock(&inode->i_mutex);
87                         return PTR_ERR(handle);
88                 }
89                 if (IS_SYNC(inode))
90                         handle->h_sync = 1;
91                 err = ext3_reserve_inode_write(handle, inode, &iloc);
92                 if (err)
93                         goto flags_err;
94
95                 flags = flags & EXT3_FL_USER_MODIFIABLE;
96                 flags |= oldflags & ~EXT3_FL_USER_MODIFIABLE;
97                 ei->i_flags = flags;
98
99                 ext3_set_inode_flags(inode);
100                 inode->i_ctime = CURRENT_TIME_SEC;
101
102                 err = ext3_mark_iloc_dirty(handle, inode, &iloc);
103 flags_err:
104                 ext3_journal_stop(handle);
105                 if (err) {
106                         mutex_unlock(&inode->i_mutex);
107                         return err;
108                 }
109
110                 if ((jflag ^ oldflags) & (EXT3_JOURNAL_DATA_FL))
111                         err = ext3_change_inode_journal_flag(inode, jflag);
112                 mutex_unlock(&inode->i_mutex);
113                 return err;
114         }
115         case EXT3_IOC_GETVERSION:
116         case EXT3_IOC_GETVERSION_OLD:
117                 return put_user(inode->i_generation, (int __user *) arg);
118         case EXT3_IOC_SETVERSION:
119         case EXT3_IOC_SETVERSION_OLD: {
120                 handle_t *handle;
121                 struct ext3_iloc iloc;
122                 __u32 generation;
123                 int err;
124
125                 if (!is_owner_or_cap(inode))
126                         return -EPERM;
127                 if (IS_RDONLY(inode))
128                         return -EROFS;
129                 if (get_user(generation, (int __user *) arg))
130                         return -EFAULT;
131
132                 handle = ext3_journal_start(inode, 1);
133                 if (IS_ERR(handle))
134                         return PTR_ERR(handle);
135                 err = ext3_reserve_inode_write(handle, inode, &iloc);
136                 if (err == 0) {
137                         inode->i_ctime = CURRENT_TIME_SEC;
138                         inode->i_generation = generation;
139                         err = ext3_mark_iloc_dirty(handle, inode, &iloc);
140                 }
141                 ext3_journal_stop(handle);
142                 return err;
143         }
144 #ifdef CONFIG_JBD_DEBUG
145         case EXT3_IOC_WAIT_FOR_READONLY:
146                 /*
147                  * This is racy - by the time we're woken up and running,
148                  * the superblock could be released.  And the module could
149                  * have been unloaded.  So sue me.
150                  *
151                  * Returns 1 if it slept, else zero.
152                  */
153                 {
154                         struct super_block *sb = inode->i_sb;
155                         DECLARE_WAITQUEUE(wait, current);
156                         int ret = 0;
157
158                         set_current_state(TASK_INTERRUPTIBLE);
159                         add_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
160                         if (timer_pending(&EXT3_SB(sb)->turn_ro_timer)) {
161                                 schedule();
162                                 ret = 1;
163                         }
164                         remove_wait_queue(&EXT3_SB(sb)->ro_wait_queue, &wait);
165                         return ret;
166                 }
167 #endif
168         case EXT3_IOC_GETRSVSZ:
169                 if (test_opt(inode->i_sb, RESERVATION)
170                         && S_ISREG(inode->i_mode)
171                         && ei->i_block_alloc_info) {
172                         rsv_window_size = ei->i_block_alloc_info->rsv_window_node.rsv_goal_size;
173                         return put_user(rsv_window_size, (int __user *)arg);
174                 }
175                 return -ENOTTY;
176         case EXT3_IOC_SETRSVSZ: {
177
178                 if (!test_opt(inode->i_sb, RESERVATION) ||!S_ISREG(inode->i_mode))
179                         return -ENOTTY;
180
181                 if (IS_RDONLY(inode))
182                         return -EROFS;
183
184                 if (!is_owner_or_cap(inode))
185                         return -EACCES;
186
187                 if (get_user(rsv_window_size, (int __user *)arg))
188                         return -EFAULT;
189
190                 if (rsv_window_size > EXT3_MAX_RESERVE_BLOCKS)
191                         rsv_window_size = EXT3_MAX_RESERVE_BLOCKS;
192
193                 /*
194                  * need to allocate reservation structure for this inode
195                  * before set the window size
196                  */
197                 mutex_lock(&ei->truncate_mutex);
198                 if (!ei->i_block_alloc_info)
199                         ext3_init_block_alloc_info(inode);
200
201                 if (ei->i_block_alloc_info){
202                         struct ext3_reserve_window_node *rsv = &ei->i_block_alloc_info->rsv_window_node;
203                         rsv->rsv_goal_size = rsv_window_size;
204                 }
205                 mutex_unlock(&ei->truncate_mutex);
206                 return 0;
207         }
208         case EXT3_IOC_GROUP_EXTEND: {
209                 ext3_fsblk_t n_blocks_count;
210                 struct super_block *sb = inode->i_sb;
211                 int err;
212
213                 if (!capable(CAP_SYS_RESOURCE))
214                         return -EPERM;
215
216                 if (IS_RDONLY(inode))
217                         return -EROFS;
218
219                 if (get_user(n_blocks_count, (__u32 __user *)arg))
220                         return -EFAULT;
221
222                 err = ext3_group_extend(sb, EXT3_SB(sb)->s_es, n_blocks_count);
223                 journal_lock_updates(EXT3_SB(sb)->s_journal);
224                 journal_flush(EXT3_SB(sb)->s_journal);
225                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
226
227                 return err;
228         }
229         case EXT3_IOC_GROUP_ADD: {
230                 struct ext3_new_group_data input;
231                 struct super_block *sb = inode->i_sb;
232                 int err;
233
234                 if (!capable(CAP_SYS_RESOURCE))
235                         return -EPERM;
236
237                 if (IS_RDONLY(inode))
238                         return -EROFS;
239
240                 if (copy_from_user(&input, (struct ext3_new_group_input __user *)arg,
241                                 sizeof(input)))
242                         return -EFAULT;
243
244                 err = ext3_group_add(sb, &input);
245                 journal_lock_updates(EXT3_SB(sb)->s_journal);
246                 journal_flush(EXT3_SB(sb)->s_journal);
247                 journal_unlock_updates(EXT3_SB(sb)->s_journal);
248
249                 return err;
250         }
251
252
253         default:
254                 return -ENOTTY;
255         }
256 }
257
258 #ifdef CONFIG_COMPAT
259 long ext3_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
260 {
261         struct inode *inode = file->f_path.dentry->d_inode;
262         int ret;
263
264         /* These are just misnamed, they actually get/put from/to user an int */
265         switch (cmd) {
266         case EXT3_IOC32_GETFLAGS:
267                 cmd = EXT3_IOC_GETFLAGS;
268                 break;
269         case EXT3_IOC32_SETFLAGS:
270                 cmd = EXT3_IOC_SETFLAGS;
271                 break;
272         case EXT3_IOC32_GETVERSION:
273                 cmd = EXT3_IOC_GETVERSION;
274                 break;
275         case EXT3_IOC32_SETVERSION:
276                 cmd = EXT3_IOC_SETVERSION;
277                 break;
278         case EXT3_IOC32_GROUP_EXTEND:
279                 cmd = EXT3_IOC_GROUP_EXTEND;
280                 break;
281         case EXT3_IOC32_GETVERSION_OLD:
282                 cmd = EXT3_IOC_GETVERSION_OLD;
283                 break;
284         case EXT3_IOC32_SETVERSION_OLD:
285                 cmd = EXT3_IOC_SETVERSION_OLD;
286                 break;
287 #ifdef CONFIG_JBD_DEBUG
288         case EXT3_IOC32_WAIT_FOR_READONLY:
289                 cmd = EXT3_IOC_WAIT_FOR_READONLY;
290                 break;
291 #endif
292         case EXT3_IOC32_GETRSVSZ:
293                 cmd = EXT3_IOC_GETRSVSZ;
294                 break;
295         case EXT3_IOC32_SETRSVSZ:
296                 cmd = EXT3_IOC_SETRSVSZ;
297                 break;
298         case EXT3_IOC_GROUP_ADD:
299                 break;
300         default:
301                 return -ENOIOCTLCMD;
302         }
303         lock_kernel();
304         ret = ext3_ioctl(inode, file, cmd, (unsigned long) compat_ptr(arg));
305         unlock_kernel();
306         return ret;
307 }
308 #endif