eb3bc2fe647e710de889f04da3afaf5821e00556
[linux-2.6.git] / fs / ext4 / ioctl.c
1 /*
2  * linux/fs/ext4/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/jbd2.h>
12 #include <linux/capability.h>
13 #include <linux/time.h>
14 #include <linux/compat.h>
15 #include <linux/mount.h>
16 #include <linux/file.h>
17 #include <asm/uaccess.h>
18 #include "ext4_jbd2.h"
19 #include "ext4.h"
20
21 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
22 {
23         struct inode *inode = filp->f_dentry->d_inode;
24         struct ext4_inode_info *ei = EXT4_I(inode);
25         unsigned int flags;
26
27         ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
28
29         switch (cmd) {
30         case EXT4_IOC_GETFLAGS:
31                 ext4_get_inode_flags(ei);
32                 flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
33                 return put_user(flags, (int __user *) arg);
34         case EXT4_IOC_SETFLAGS: {
35                 handle_t *handle = NULL;
36                 int err, migrate = 0;
37                 struct ext4_iloc iloc;
38                 unsigned int oldflags;
39                 unsigned int jflag;
40
41                 if (!is_owner_or_cap(inode))
42                         return -EACCES;
43
44                 if (get_user(flags, (int __user *) arg))
45                         return -EFAULT;
46
47                 err = mnt_want_write(filp->f_path.mnt);
48                 if (err)
49                         return err;
50
51                 flags = ext4_mask_flags(inode->i_mode, flags);
52
53                 err = -EPERM;
54                 mutex_lock(&inode->i_mutex);
55                 /* Is it quota file? Do not allow user to mess with it */
56                 if (IS_NOQUOTA(inode))
57                         goto flags_out;
58
59                 oldflags = ei->i_flags;
60
61                 /* The JOURNAL_DATA flag is modifiable only by root */
62                 jflag = flags & EXT4_JOURNAL_DATA_FL;
63
64                 /*
65                  * The IMMUTABLE and APPEND_ONLY flags can only be changed by
66                  * the relevant capability.
67                  *
68                  * This test looks nicer. Thanks to Pauline Middelink
69                  */
70                 if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
71                         if (!capable(CAP_LINUX_IMMUTABLE))
72                                 goto flags_out;
73                 }
74
75                 /*
76                  * The JOURNAL_DATA flag can only be changed by
77                  * the relevant capability.
78                  */
79                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
80                         if (!capable(CAP_SYS_RESOURCE))
81                                 goto flags_out;
82                 }
83                 if (oldflags & EXT4_EXTENTS_FL) {
84                         /* We don't support clearning extent flags */
85                         if (!(flags & EXT4_EXTENTS_FL)) {
86                                 err = -EOPNOTSUPP;
87                                 goto flags_out;
88                         }
89                 } else if (flags & EXT4_EXTENTS_FL) {
90                         /* migrate the file */
91                         migrate = 1;
92                         flags &= ~EXT4_EXTENTS_FL;
93                 }
94
95                 if (flags & EXT4_EOFBLOCKS_FL) {
96                         /* we don't support adding EOFBLOCKS flag */
97                         if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
98                                 err = -EOPNOTSUPP;
99                                 goto flags_out;
100                         }
101                 } else if (oldflags & EXT4_EOFBLOCKS_FL)
102                         ext4_truncate(inode);
103
104                 handle = ext4_journal_start(inode, 1);
105                 if (IS_ERR(handle)) {
106                         err = PTR_ERR(handle);
107                         goto flags_out;
108                 }
109                 if (IS_SYNC(inode))
110                         ext4_handle_sync(handle);
111                 err = ext4_reserve_inode_write(handle, inode, &iloc);
112                 if (err)
113                         goto flags_err;
114
115                 flags = flags & EXT4_FL_USER_MODIFIABLE;
116                 flags |= oldflags & ~EXT4_FL_USER_MODIFIABLE;
117                 ei->i_flags = flags;
118
119                 ext4_set_inode_flags(inode);
120                 inode->i_ctime = ext4_current_time(inode);
121
122                 err = ext4_mark_iloc_dirty(handle, inode, &iloc);
123 flags_err:
124                 ext4_journal_stop(handle);
125                 if (err)
126                         goto flags_out;
127
128                 if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
129                         err = ext4_change_inode_journal_flag(inode, jflag);
130                 if (err)
131                         goto flags_out;
132                 if (migrate)
133                         err = ext4_ext_migrate(inode);
134 flags_out:
135                 mutex_unlock(&inode->i_mutex);
136                 mnt_drop_write(filp->f_path.mnt);
137                 return err;
138         }
139         case EXT4_IOC_GETVERSION:
140         case EXT4_IOC_GETVERSION_OLD:
141                 return put_user(inode->i_generation, (int __user *) arg);
142         case EXT4_IOC_SETVERSION:
143         case EXT4_IOC_SETVERSION_OLD: {
144                 handle_t *handle;
145                 struct ext4_iloc iloc;
146                 __u32 generation;
147                 int err;
148
149                 if (!is_owner_or_cap(inode))
150                         return -EPERM;
151
152                 err = mnt_want_write(filp->f_path.mnt);
153                 if (err)
154                         return err;
155                 if (get_user(generation, (int __user *) arg)) {
156                         err = -EFAULT;
157                         goto setversion_out;
158                 }
159
160                 handle = ext4_journal_start(inode, 1);
161                 if (IS_ERR(handle)) {
162                         err = PTR_ERR(handle);
163                         goto setversion_out;
164                 }
165                 err = ext4_reserve_inode_write(handle, inode, &iloc);
166                 if (err == 0) {
167                         inode->i_ctime = ext4_current_time(inode);
168                         inode->i_generation = generation;
169                         err = ext4_mark_iloc_dirty(handle, inode, &iloc);
170                 }
171                 ext4_journal_stop(handle);
172 setversion_out:
173                 mnt_drop_write(filp->f_path.mnt);
174                 return err;
175         }
176 #ifdef CONFIG_JBD2_DEBUG
177         case EXT4_IOC_WAIT_FOR_READONLY:
178                 /*
179                  * This is racy - by the time we're woken up and running,
180                  * the superblock could be released.  And the module could
181                  * have been unloaded.  So sue me.
182                  *
183                  * Returns 1 if it slept, else zero.
184                  */
185                 {
186                         struct super_block *sb = inode->i_sb;
187                         DECLARE_WAITQUEUE(wait, current);
188                         int ret = 0;
189
190                         set_current_state(TASK_INTERRUPTIBLE);
191                         add_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
192                         if (timer_pending(&EXT4_SB(sb)->turn_ro_timer)) {
193                                 schedule();
194                                 ret = 1;
195                         }
196                         remove_wait_queue(&EXT4_SB(sb)->ro_wait_queue, &wait);
197                         return ret;
198                 }
199 #endif
200         case EXT4_IOC_GROUP_EXTEND: {
201                 ext4_fsblk_t n_blocks_count;
202                 struct super_block *sb = inode->i_sb;
203                 int err, err2=0;
204
205                 if (!capable(CAP_SYS_RESOURCE))
206                         return -EPERM;
207
208                 if (get_user(n_blocks_count, (__u32 __user *)arg))
209                         return -EFAULT;
210
211                 err = mnt_want_write(filp->f_path.mnt);
212                 if (err)
213                         return err;
214
215                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
216                 if (EXT4_SB(sb)->s_journal) {
217                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
218                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
219                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
220                 }
221                 if (err == 0)
222                         err = err2;
223                 mnt_drop_write(filp->f_path.mnt);
224
225                 return err;
226         }
227
228         case EXT4_IOC_MOVE_EXT: {
229                 struct move_extent me;
230                 struct file *donor_filp;
231                 int err;
232
233                 if (!(filp->f_mode & FMODE_READ) ||
234                     !(filp->f_mode & FMODE_WRITE))
235                         return -EBADF;
236
237                 if (copy_from_user(&me,
238                         (struct move_extent __user *)arg, sizeof(me)))
239                         return -EFAULT;
240                 me.moved_len = 0;
241
242                 donor_filp = fget(me.donor_fd);
243                 if (!donor_filp)
244                         return -EBADF;
245
246                 if (!(donor_filp->f_mode & FMODE_WRITE)) {
247                         err = -EBADF;
248                         goto mext_out;
249                 }
250
251                 err = mnt_want_write(filp->f_path.mnt);
252                 if (err)
253                         goto mext_out;
254
255                 err = ext4_move_extents(filp, donor_filp, me.orig_start,
256                                         me.donor_start, me.len, &me.moved_len);
257                 mnt_drop_write(filp->f_path.mnt);
258                 if (me.moved_len > 0)
259                         file_remove_suid(donor_filp);
260
261                 if (copy_to_user((struct move_extent __user *)arg,
262                                  &me, sizeof(me)))
263                         err = -EFAULT;
264 mext_out:
265                 fput(donor_filp);
266                 return err;
267         }
268
269         case EXT4_IOC_GROUP_ADD: {
270                 struct ext4_new_group_data input;
271                 struct super_block *sb = inode->i_sb;
272                 int err, err2=0;
273
274                 if (!capable(CAP_SYS_RESOURCE))
275                         return -EPERM;
276
277                 if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
278                                 sizeof(input)))
279                         return -EFAULT;
280
281                 err = mnt_want_write(filp->f_path.mnt);
282                 if (err)
283                         return err;
284
285                 err = ext4_group_add(sb, &input);
286                 if (EXT4_SB(sb)->s_journal) {
287                         jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
288                         err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
289                         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
290                 }
291                 if (err == 0)
292                         err = err2;
293                 mnt_drop_write(filp->f_path.mnt);
294
295                 return err;
296         }
297
298         case EXT4_IOC_MIGRATE:
299         {
300                 int err;
301                 if (!is_owner_or_cap(inode))
302                         return -EACCES;
303
304                 err = mnt_want_write(filp->f_path.mnt);
305                 if (err)
306                         return err;
307                 /*
308                  * inode_mutex prevent write and truncate on the file.
309                  * Read still goes through. We take i_data_sem in
310                  * ext4_ext_swap_inode_data before we switch the
311                  * inode format to prevent read.
312                  */
313                 mutex_lock(&(inode->i_mutex));
314                 err = ext4_ext_migrate(inode);
315                 mutex_unlock(&(inode->i_mutex));
316                 mnt_drop_write(filp->f_path.mnt);
317                 return err;
318         }
319
320         case EXT4_IOC_ALLOC_DA_BLKS:
321         {
322                 int err;
323                 if (!is_owner_or_cap(inode))
324                         return -EACCES;
325
326                 err = mnt_want_write(filp->f_path.mnt);
327                 if (err)
328                         return err;
329                 err = ext4_alloc_da_blocks(inode);
330                 mnt_drop_write(filp->f_path.mnt);
331                 return err;
332         }
333
334         case FITRIM:
335         {
336                 struct super_block *sb = inode->i_sb;
337                 struct fstrim_range range;
338                 int ret = 0;
339
340                 if (!capable(CAP_SYS_ADMIN))
341                         return -EPERM;
342
343                 if (copy_from_user(&range, (struct fstrim_range *)arg,
344                     sizeof(range)))
345                         return -EFAULT;
346
347                 ret = ext4_trim_fs(sb, &range);
348                 if (ret < 0)
349                         return ret;
350
351                 if (copy_to_user((struct fstrim_range *)arg, &range,
352                     sizeof(range)))
353                         return -EFAULT;
354
355                 return 0;
356         }
357
358         default:
359                 return -ENOTTY;
360         }
361 }
362
363 #ifdef CONFIG_COMPAT
364 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
365 {
366         /* These are just misnamed, they actually get/put from/to user an int */
367         switch (cmd) {
368         case EXT4_IOC32_GETFLAGS:
369                 cmd = EXT4_IOC_GETFLAGS;
370                 break;
371         case EXT4_IOC32_SETFLAGS:
372                 cmd = EXT4_IOC_SETFLAGS;
373                 break;
374         case EXT4_IOC32_GETVERSION:
375                 cmd = EXT4_IOC_GETVERSION;
376                 break;
377         case EXT4_IOC32_SETVERSION:
378                 cmd = EXT4_IOC_SETVERSION;
379                 break;
380         case EXT4_IOC32_GROUP_EXTEND:
381                 cmd = EXT4_IOC_GROUP_EXTEND;
382                 break;
383         case EXT4_IOC32_GETVERSION_OLD:
384                 cmd = EXT4_IOC_GETVERSION_OLD;
385                 break;
386         case EXT4_IOC32_SETVERSION_OLD:
387                 cmd = EXT4_IOC_SETVERSION_OLD;
388                 break;
389 #ifdef CONFIG_JBD2_DEBUG
390         case EXT4_IOC32_WAIT_FOR_READONLY:
391                 cmd = EXT4_IOC_WAIT_FOR_READONLY;
392                 break;
393 #endif
394         case EXT4_IOC32_GETRSVSZ:
395                 cmd = EXT4_IOC_GETRSVSZ;
396                 break;
397         case EXT4_IOC32_SETRSVSZ:
398                 cmd = EXT4_IOC_SETRSVSZ;
399                 break;
400         case EXT4_IOC32_GROUP_ADD: {
401                 struct compat_ext4_new_group_input __user *uinput;
402                 struct ext4_new_group_input input;
403                 mm_segment_t old_fs;
404                 int err;
405
406                 uinput = compat_ptr(arg);
407                 err = get_user(input.group, &uinput->group);
408                 err |= get_user(input.block_bitmap, &uinput->block_bitmap);
409                 err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
410                 err |= get_user(input.inode_table, &uinput->inode_table);
411                 err |= get_user(input.blocks_count, &uinput->blocks_count);
412                 err |= get_user(input.reserved_blocks,
413                                 &uinput->reserved_blocks);
414                 if (err)
415                         return -EFAULT;
416                 old_fs = get_fs();
417                 set_fs(KERNEL_DS);
418                 err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
419                                  (unsigned long) &input);
420                 set_fs(old_fs);
421                 return err;
422         }
423         case EXT4_IOC_MOVE_EXT:
424                 break;
425         default:
426                 return -ENOIOCTLCMD;
427         }
428         return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
429 }
430 #endif