xref: /linux/fs/ext4/ioctl.c (revision 861e10be08c69808065d755d3e3cab5d520a2d32)
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 #define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)
22 
23 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
24 {
25 	struct inode *inode = filp->f_dentry->d_inode;
26 	struct super_block *sb = inode->i_sb;
27 	struct ext4_inode_info *ei = EXT4_I(inode);
28 	unsigned int flags;
29 
30 	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
31 
32 	switch (cmd) {
33 	case EXT4_IOC_GETFLAGS:
34 		ext4_get_inode_flags(ei);
35 		flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
36 		return put_user(flags, (int __user *) arg);
37 	case EXT4_IOC_SETFLAGS: {
38 		handle_t *handle = NULL;
39 		int err, migrate = 0;
40 		struct ext4_iloc iloc;
41 		unsigned int oldflags, mask, i;
42 		unsigned int jflag;
43 
44 		if (!inode_owner_or_capable(inode))
45 			return -EACCES;
46 
47 		if (get_user(flags, (int __user *) arg))
48 			return -EFAULT;
49 
50 		err = mnt_want_write_file(filp);
51 		if (err)
52 			return err;
53 
54 		flags = ext4_mask_flags(inode->i_mode, flags);
55 
56 		err = -EPERM;
57 		mutex_lock(&inode->i_mutex);
58 		/* Is it quota file? Do not allow user to mess with it */
59 		if (IS_NOQUOTA(inode))
60 			goto flags_out;
61 
62 		oldflags = ei->i_flags;
63 
64 		/* The JOURNAL_DATA flag is modifiable only by root */
65 		jflag = flags & EXT4_JOURNAL_DATA_FL;
66 
67 		/*
68 		 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
69 		 * the relevant capability.
70 		 *
71 		 * This test looks nicer. Thanks to Pauline Middelink
72 		 */
73 		if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
74 			if (!capable(CAP_LINUX_IMMUTABLE))
75 				goto flags_out;
76 		}
77 
78 		/*
79 		 * The JOURNAL_DATA flag can only be changed by
80 		 * the relevant capability.
81 		 */
82 		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
83 			if (!capable(CAP_SYS_RESOURCE))
84 				goto flags_out;
85 		}
86 		if (oldflags & EXT4_EXTENTS_FL) {
87 			/* We don't support clearning extent flags */
88 			if (!(flags & EXT4_EXTENTS_FL)) {
89 				err = -EOPNOTSUPP;
90 				goto flags_out;
91 			}
92 		} else if (flags & EXT4_EXTENTS_FL) {
93 			/* migrate the file */
94 			migrate = 1;
95 			flags &= ~EXT4_EXTENTS_FL;
96 		}
97 
98 		if (flags & EXT4_EOFBLOCKS_FL) {
99 			/* we don't support adding EOFBLOCKS flag */
100 			if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
101 				err = -EOPNOTSUPP;
102 				goto flags_out;
103 			}
104 		} else if (oldflags & EXT4_EOFBLOCKS_FL)
105 			ext4_truncate(inode);
106 
107 		handle = ext4_journal_start(inode, 1);
108 		if (IS_ERR(handle)) {
109 			err = PTR_ERR(handle);
110 			goto flags_out;
111 		}
112 		if (IS_SYNC(inode))
113 			ext4_handle_sync(handle);
114 		err = ext4_reserve_inode_write(handle, inode, &iloc);
115 		if (err)
116 			goto flags_err;
117 
118 		for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
119 			if (!(mask & EXT4_FL_USER_MODIFIABLE))
120 				continue;
121 			if (mask & flags)
122 				ext4_set_inode_flag(inode, i);
123 			else
124 				ext4_clear_inode_flag(inode, i);
125 		}
126 
127 		ext4_set_inode_flags(inode);
128 		inode->i_ctime = ext4_current_time(inode);
129 
130 		err = ext4_mark_iloc_dirty(handle, inode, &iloc);
131 flags_err:
132 		ext4_journal_stop(handle);
133 		if (err)
134 			goto flags_out;
135 
136 		if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
137 			err = ext4_change_inode_journal_flag(inode, jflag);
138 		if (err)
139 			goto flags_out;
140 		if (migrate)
141 			err = ext4_ext_migrate(inode);
142 flags_out:
143 		mutex_unlock(&inode->i_mutex);
144 		mnt_drop_write_file(filp);
145 		return err;
146 	}
147 	case EXT4_IOC_GETVERSION:
148 	case EXT4_IOC_GETVERSION_OLD:
149 		return put_user(inode->i_generation, (int __user *) arg);
150 	case EXT4_IOC_SETVERSION:
151 	case EXT4_IOC_SETVERSION_OLD: {
152 		handle_t *handle;
153 		struct ext4_iloc iloc;
154 		__u32 generation;
155 		int err;
156 
157 		if (!inode_owner_or_capable(inode))
158 			return -EPERM;
159 
160 		if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
161 				EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
162 			ext4_warning(sb, "Setting inode version is not "
163 				     "supported with metadata_csum enabled.");
164 			return -ENOTTY;
165 		}
166 
167 		err = mnt_want_write_file(filp);
168 		if (err)
169 			return err;
170 		if (get_user(generation, (int __user *) arg)) {
171 			err = -EFAULT;
172 			goto setversion_out;
173 		}
174 
175 		mutex_lock(&inode->i_mutex);
176 		handle = ext4_journal_start(inode, 1);
177 		if (IS_ERR(handle)) {
178 			err = PTR_ERR(handle);
179 			goto unlock_out;
180 		}
181 		err = ext4_reserve_inode_write(handle, inode, &iloc);
182 		if (err == 0) {
183 			inode->i_ctime = ext4_current_time(inode);
184 			inode->i_generation = generation;
185 			err = ext4_mark_iloc_dirty(handle, inode, &iloc);
186 		}
187 		ext4_journal_stop(handle);
188 
189 unlock_out:
190 		mutex_unlock(&inode->i_mutex);
191 setversion_out:
192 		mnt_drop_write_file(filp);
193 		return err;
194 	}
195 	case EXT4_IOC_GROUP_EXTEND: {
196 		ext4_fsblk_t n_blocks_count;
197 		int err, err2=0;
198 
199 		err = ext4_resize_begin(sb);
200 		if (err)
201 			return err;
202 
203 		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
204 			err = -EFAULT;
205 			goto group_extend_out;
206 		}
207 
208 		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
209 			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
210 			ext4_msg(sb, KERN_ERR,
211 				 "Online resizing not supported with bigalloc");
212 			err = -EOPNOTSUPP;
213 			goto group_extend_out;
214 		}
215 
216 		err = mnt_want_write_file(filp);
217 		if (err)
218 			goto group_extend_out;
219 
220 		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
221 		if (EXT4_SB(sb)->s_journal) {
222 			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
223 			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
224 			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
225 		}
226 		if (err == 0)
227 			err = err2;
228 		mnt_drop_write_file(filp);
229 group_extend_out:
230 		ext4_resize_end(sb);
231 		return err;
232 	}
233 
234 	case EXT4_IOC_MOVE_EXT: {
235 		struct move_extent me;
236 		struct fd donor;
237 		int err;
238 
239 		if (!(filp->f_mode & FMODE_READ) ||
240 		    !(filp->f_mode & FMODE_WRITE))
241 			return -EBADF;
242 
243 		if (copy_from_user(&me,
244 			(struct move_extent __user *)arg, sizeof(me)))
245 			return -EFAULT;
246 		me.moved_len = 0;
247 
248 		donor = fdget(me.donor_fd);
249 		if (!donor.file)
250 			return -EBADF;
251 
252 		if (!(donor.file->f_mode & FMODE_WRITE)) {
253 			err = -EBADF;
254 			goto mext_out;
255 		}
256 
257 		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
258 			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
259 			ext4_msg(sb, KERN_ERR,
260 				 "Online defrag not supported with bigalloc");
261 			err = -EOPNOTSUPP;
262 			goto mext_out;
263 		}
264 
265 		err = mnt_want_write_file(filp);
266 		if (err)
267 			goto mext_out;
268 
269 		err = ext4_move_extents(filp, donor.file, me.orig_start,
270 					me.donor_start, me.len, &me.moved_len);
271 		mnt_drop_write_file(filp);
272 
273 		if (copy_to_user((struct move_extent __user *)arg,
274 				 &me, sizeof(me)))
275 			err = -EFAULT;
276 mext_out:
277 		fdput(donor);
278 		return err;
279 	}
280 
281 	case EXT4_IOC_GROUP_ADD: {
282 		struct ext4_new_group_data input;
283 		int err, err2=0;
284 
285 		err = ext4_resize_begin(sb);
286 		if (err)
287 			return err;
288 
289 		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
290 				sizeof(input))) {
291 			err = -EFAULT;
292 			goto group_add_out;
293 		}
294 
295 		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
296 			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
297 			ext4_msg(sb, KERN_ERR,
298 				 "Online resizing not supported with bigalloc");
299 			err = -EOPNOTSUPP;
300 			goto group_add_out;
301 		}
302 
303 		err = mnt_want_write_file(filp);
304 		if (err)
305 			goto group_add_out;
306 
307 		err = ext4_group_add(sb, &input);
308 		if (EXT4_SB(sb)->s_journal) {
309 			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
310 			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
311 			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
312 		}
313 		if (err == 0)
314 			err = err2;
315 		mnt_drop_write_file(filp);
316 group_add_out:
317 		ext4_resize_end(sb);
318 		return err;
319 	}
320 
321 	case EXT4_IOC_MIGRATE:
322 	{
323 		int err;
324 		if (!inode_owner_or_capable(inode))
325 			return -EACCES;
326 
327 		err = mnt_want_write_file(filp);
328 		if (err)
329 			return err;
330 		/*
331 		 * inode_mutex prevent write and truncate on the file.
332 		 * Read still goes through. We take i_data_sem in
333 		 * ext4_ext_swap_inode_data before we switch the
334 		 * inode format to prevent read.
335 		 */
336 		mutex_lock(&(inode->i_mutex));
337 		err = ext4_ext_migrate(inode);
338 		mutex_unlock(&(inode->i_mutex));
339 		mnt_drop_write_file(filp);
340 		return err;
341 	}
342 
343 	case EXT4_IOC_ALLOC_DA_BLKS:
344 	{
345 		int err;
346 		if (!inode_owner_or_capable(inode))
347 			return -EACCES;
348 
349 		err = mnt_want_write_file(filp);
350 		if (err)
351 			return err;
352 		err = ext4_alloc_da_blocks(inode);
353 		mnt_drop_write_file(filp);
354 		return err;
355 	}
356 
357 	case EXT4_IOC_RESIZE_FS: {
358 		ext4_fsblk_t n_blocks_count;
359 		struct super_block *sb = inode->i_sb;
360 		int err = 0, err2 = 0;
361 
362 		if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
363 			       EXT4_FEATURE_RO_COMPAT_BIGALLOC)) {
364 			ext4_msg(sb, KERN_ERR,
365 				 "Online resizing not (yet) supported with bigalloc");
366 			return -EOPNOTSUPP;
367 		}
368 
369 		if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
370 				   sizeof(__u64))) {
371 			return -EFAULT;
372 		}
373 
374 		err = ext4_resize_begin(sb);
375 		if (err)
376 			return err;
377 
378 		err = mnt_want_write_file(filp);
379 		if (err)
380 			goto resizefs_out;
381 
382 		err = ext4_resize_fs(sb, n_blocks_count);
383 		if (EXT4_SB(sb)->s_journal) {
384 			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
385 			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
386 			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
387 		}
388 		if (err == 0)
389 			err = err2;
390 		mnt_drop_write_file(filp);
391 resizefs_out:
392 		ext4_resize_end(sb);
393 		return err;
394 	}
395 
396 	case FITRIM:
397 	{
398 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
399 		struct fstrim_range range;
400 		int ret = 0;
401 
402 		if (!capable(CAP_SYS_ADMIN))
403 			return -EPERM;
404 
405 		if (!blk_queue_discard(q))
406 			return -EOPNOTSUPP;
407 
408 		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
409 		    sizeof(range)))
410 			return -EFAULT;
411 
412 		range.minlen = max((unsigned int)range.minlen,
413 				   q->limits.discard_granularity);
414 		ret = ext4_trim_fs(sb, &range);
415 		if (ret < 0)
416 			return ret;
417 
418 		if (copy_to_user((struct fstrim_range __user *)arg, &range,
419 		    sizeof(range)))
420 			return -EFAULT;
421 
422 		return 0;
423 	}
424 
425 	default:
426 		return -ENOTTY;
427 	}
428 }
429 
430 #ifdef CONFIG_COMPAT
431 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
432 {
433 	/* These are just misnamed, they actually get/put from/to user an int */
434 	switch (cmd) {
435 	case EXT4_IOC32_GETFLAGS:
436 		cmd = EXT4_IOC_GETFLAGS;
437 		break;
438 	case EXT4_IOC32_SETFLAGS:
439 		cmd = EXT4_IOC_SETFLAGS;
440 		break;
441 	case EXT4_IOC32_GETVERSION:
442 		cmd = EXT4_IOC_GETVERSION;
443 		break;
444 	case EXT4_IOC32_SETVERSION:
445 		cmd = EXT4_IOC_SETVERSION;
446 		break;
447 	case EXT4_IOC32_GROUP_EXTEND:
448 		cmd = EXT4_IOC_GROUP_EXTEND;
449 		break;
450 	case EXT4_IOC32_GETVERSION_OLD:
451 		cmd = EXT4_IOC_GETVERSION_OLD;
452 		break;
453 	case EXT4_IOC32_SETVERSION_OLD:
454 		cmd = EXT4_IOC_SETVERSION_OLD;
455 		break;
456 	case EXT4_IOC32_GETRSVSZ:
457 		cmd = EXT4_IOC_GETRSVSZ;
458 		break;
459 	case EXT4_IOC32_SETRSVSZ:
460 		cmd = EXT4_IOC_SETRSVSZ;
461 		break;
462 	case EXT4_IOC32_GROUP_ADD: {
463 		struct compat_ext4_new_group_input __user *uinput;
464 		struct ext4_new_group_input input;
465 		mm_segment_t old_fs;
466 		int err;
467 
468 		uinput = compat_ptr(arg);
469 		err = get_user(input.group, &uinput->group);
470 		err |= get_user(input.block_bitmap, &uinput->block_bitmap);
471 		err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
472 		err |= get_user(input.inode_table, &uinput->inode_table);
473 		err |= get_user(input.blocks_count, &uinput->blocks_count);
474 		err |= get_user(input.reserved_blocks,
475 				&uinput->reserved_blocks);
476 		if (err)
477 			return -EFAULT;
478 		old_fs = get_fs();
479 		set_fs(KERNEL_DS);
480 		err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
481 				 (unsigned long) &input);
482 		set_fs(old_fs);
483 		return err;
484 	}
485 	case EXT4_IOC_MOVE_EXT:
486 	case FITRIM:
487 	case EXT4_IOC_RESIZE_FS:
488 		break;
489 	default:
490 		return -ENOIOCTLCMD;
491 	}
492 	return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
493 }
494 #endif
495