xref: /openbmc/linux/fs/ext4/ioctl.c (revision 293d5b43)
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/capability.h>
12 #include <linux/time.h>
13 #include <linux/compat.h>
14 #include <linux/mount.h>
15 #include <linux/file.h>
16 #include <linux/quotaops.h>
17 #include <linux/uuid.h>
18 #include <asm/uaccess.h>
19 #include "ext4_jbd2.h"
20 #include "ext4.h"
21 
22 #define MAX_32_NUM ((((unsigned long long) 1) << 32) - 1)
23 
24 /**
25  * Swap memory between @a and @b for @len bytes.
26  *
27  * @a:          pointer to first memory area
28  * @b:          pointer to second memory area
29  * @len:        number of bytes to swap
30  *
31  */
32 static void memswap(void *a, void *b, size_t len)
33 {
34 	unsigned char *ap, *bp;
35 
36 	ap = (unsigned char *)a;
37 	bp = (unsigned char *)b;
38 	while (len-- > 0) {
39 		swap(*ap, *bp);
40 		ap++;
41 		bp++;
42 	}
43 }
44 
45 /**
46  * Swap i_data and associated attributes between @inode1 and @inode2.
47  * This function is used for the primary swap between inode1 and inode2
48  * and also to revert this primary swap in case of errors.
49  *
50  * Therefore you have to make sure, that calling this method twice
51  * will revert all changes.
52  *
53  * @inode1:     pointer to first inode
54  * @inode2:     pointer to second inode
55  */
56 static void swap_inode_data(struct inode *inode1, struct inode *inode2)
57 {
58 	loff_t isize;
59 	struct ext4_inode_info *ei1;
60 	struct ext4_inode_info *ei2;
61 
62 	ei1 = EXT4_I(inode1);
63 	ei2 = EXT4_I(inode2);
64 
65 	memswap(&inode1->i_flags, &inode2->i_flags, sizeof(inode1->i_flags));
66 	memswap(&inode1->i_version, &inode2->i_version,
67 		  sizeof(inode1->i_version));
68 	memswap(&inode1->i_blocks, &inode2->i_blocks,
69 		  sizeof(inode1->i_blocks));
70 	memswap(&inode1->i_bytes, &inode2->i_bytes, sizeof(inode1->i_bytes));
71 	memswap(&inode1->i_atime, &inode2->i_atime, sizeof(inode1->i_atime));
72 	memswap(&inode1->i_mtime, &inode2->i_mtime, sizeof(inode1->i_mtime));
73 
74 	memswap(ei1->i_data, ei2->i_data, sizeof(ei1->i_data));
75 	memswap(&ei1->i_flags, &ei2->i_flags, sizeof(ei1->i_flags));
76 	memswap(&ei1->i_disksize, &ei2->i_disksize, sizeof(ei1->i_disksize));
77 	ext4_es_remove_extent(inode1, 0, EXT_MAX_BLOCKS);
78 	ext4_es_remove_extent(inode2, 0, EXT_MAX_BLOCKS);
79 
80 	isize = i_size_read(inode1);
81 	i_size_write(inode1, i_size_read(inode2));
82 	i_size_write(inode2, isize);
83 }
84 
85 /**
86  * Swap the information from the given @inode and the inode
87  * EXT4_BOOT_LOADER_INO. It will basically swap i_data and all other
88  * important fields of the inodes.
89  *
90  * @sb:         the super block of the filesystem
91  * @inode:      the inode to swap with EXT4_BOOT_LOADER_INO
92  *
93  */
94 static long swap_inode_boot_loader(struct super_block *sb,
95 				struct inode *inode)
96 {
97 	handle_t *handle;
98 	int err;
99 	struct inode *inode_bl;
100 	struct ext4_inode_info *ei_bl;
101 	struct ext4_sb_info *sbi = EXT4_SB(sb);
102 
103 	if (inode->i_nlink != 1 || !S_ISREG(inode->i_mode))
104 		return -EINVAL;
105 
106 	if (!inode_owner_or_capable(inode) || !capable(CAP_SYS_ADMIN))
107 		return -EPERM;
108 
109 	inode_bl = ext4_iget(sb, EXT4_BOOT_LOADER_INO);
110 	if (IS_ERR(inode_bl))
111 		return PTR_ERR(inode_bl);
112 	ei_bl = EXT4_I(inode_bl);
113 
114 	filemap_flush(inode->i_mapping);
115 	filemap_flush(inode_bl->i_mapping);
116 
117 	/* Protect orig inodes against a truncate and make sure,
118 	 * that only 1 swap_inode_boot_loader is running. */
119 	lock_two_nondirectories(inode, inode_bl);
120 
121 	truncate_inode_pages(&inode->i_data, 0);
122 	truncate_inode_pages(&inode_bl->i_data, 0);
123 
124 	/* Wait for all existing dio workers */
125 	ext4_inode_block_unlocked_dio(inode);
126 	ext4_inode_block_unlocked_dio(inode_bl);
127 	inode_dio_wait(inode);
128 	inode_dio_wait(inode_bl);
129 
130 	handle = ext4_journal_start(inode_bl, EXT4_HT_MOVE_EXTENTS, 2);
131 	if (IS_ERR(handle)) {
132 		err = -EINVAL;
133 		goto journal_err_out;
134 	}
135 
136 	/* Protect extent tree against block allocations via delalloc */
137 	ext4_double_down_write_data_sem(inode, inode_bl);
138 
139 	if (inode_bl->i_nlink == 0) {
140 		/* this inode has never been used as a BOOT_LOADER */
141 		set_nlink(inode_bl, 1);
142 		i_uid_write(inode_bl, 0);
143 		i_gid_write(inode_bl, 0);
144 		inode_bl->i_flags = 0;
145 		ei_bl->i_flags = 0;
146 		inode_bl->i_version = 1;
147 		i_size_write(inode_bl, 0);
148 		inode_bl->i_mode = S_IFREG;
149 		if (ext4_has_feature_extents(sb)) {
150 			ext4_set_inode_flag(inode_bl, EXT4_INODE_EXTENTS);
151 			ext4_ext_tree_init(handle, inode_bl);
152 		} else
153 			memset(ei_bl->i_data, 0, sizeof(ei_bl->i_data));
154 	}
155 
156 	swap_inode_data(inode, inode_bl);
157 
158 	inode->i_ctime = inode_bl->i_ctime = ext4_current_time(inode);
159 
160 	spin_lock(&sbi->s_next_gen_lock);
161 	inode->i_generation = sbi->s_next_generation++;
162 	inode_bl->i_generation = sbi->s_next_generation++;
163 	spin_unlock(&sbi->s_next_gen_lock);
164 
165 	ext4_discard_preallocations(inode);
166 
167 	err = ext4_mark_inode_dirty(handle, inode);
168 	if (err < 0) {
169 		ext4_warning(inode->i_sb,
170 			"couldn't mark inode #%lu dirty (err %d)",
171 			inode->i_ino, err);
172 		/* Revert all changes: */
173 		swap_inode_data(inode, inode_bl);
174 	} else {
175 		err = ext4_mark_inode_dirty(handle, inode_bl);
176 		if (err < 0) {
177 			ext4_warning(inode_bl->i_sb,
178 				"couldn't mark inode #%lu dirty (err %d)",
179 				inode_bl->i_ino, err);
180 			/* Revert all changes: */
181 			swap_inode_data(inode, inode_bl);
182 			ext4_mark_inode_dirty(handle, inode);
183 		}
184 	}
185 	ext4_journal_stop(handle);
186 	ext4_double_up_write_data_sem(inode, inode_bl);
187 
188 journal_err_out:
189 	ext4_inode_resume_unlocked_dio(inode);
190 	ext4_inode_resume_unlocked_dio(inode_bl);
191 	unlock_two_nondirectories(inode, inode_bl);
192 	iput(inode_bl);
193 	return err;
194 }
195 
196 static int uuid_is_zero(__u8 u[16])
197 {
198 	int	i;
199 
200 	for (i = 0; i < 16; i++)
201 		if (u[i])
202 			return 0;
203 	return 1;
204 }
205 
206 static int ext4_ioctl_setflags(struct inode *inode,
207 			       unsigned int flags)
208 {
209 	struct ext4_inode_info *ei = EXT4_I(inode);
210 	handle_t *handle = NULL;
211 	int err = -EPERM, migrate = 0;
212 	struct ext4_iloc iloc;
213 	unsigned int oldflags, mask, i;
214 	unsigned int jflag;
215 
216 	/* Is it quota file? Do not allow user to mess with it */
217 	if (IS_NOQUOTA(inode))
218 		goto flags_out;
219 
220 	oldflags = ei->i_flags;
221 
222 	/* The JOURNAL_DATA flag is modifiable only by root */
223 	jflag = flags & EXT4_JOURNAL_DATA_FL;
224 
225 	/*
226 	 * The IMMUTABLE and APPEND_ONLY flags can only be changed by
227 	 * the relevant capability.
228 	 *
229 	 * This test looks nicer. Thanks to Pauline Middelink
230 	 */
231 	if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) {
232 		if (!capable(CAP_LINUX_IMMUTABLE))
233 			goto flags_out;
234 	}
235 
236 	/*
237 	 * The JOURNAL_DATA flag can only be changed by
238 	 * the relevant capability.
239 	 */
240 	if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL)) {
241 		if (!capable(CAP_SYS_RESOURCE))
242 			goto flags_out;
243 	}
244 	if ((flags ^ oldflags) & EXT4_EXTENTS_FL)
245 		migrate = 1;
246 
247 	if (flags & EXT4_EOFBLOCKS_FL) {
248 		/* we don't support adding EOFBLOCKS flag */
249 		if (!(oldflags & EXT4_EOFBLOCKS_FL)) {
250 			err = -EOPNOTSUPP;
251 			goto flags_out;
252 		}
253 	} else if (oldflags & EXT4_EOFBLOCKS_FL)
254 		ext4_truncate(inode);
255 
256 	handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
257 	if (IS_ERR(handle)) {
258 		err = PTR_ERR(handle);
259 		goto flags_out;
260 	}
261 	if (IS_SYNC(inode))
262 		ext4_handle_sync(handle);
263 	err = ext4_reserve_inode_write(handle, inode, &iloc);
264 	if (err)
265 		goto flags_err;
266 
267 	for (i = 0, mask = 1; i < 32; i++, mask <<= 1) {
268 		if (!(mask & EXT4_FL_USER_MODIFIABLE))
269 			continue;
270 		if (mask & flags)
271 			ext4_set_inode_flag(inode, i);
272 		else
273 			ext4_clear_inode_flag(inode, i);
274 	}
275 
276 	ext4_set_inode_flags(inode);
277 	inode->i_ctime = ext4_current_time(inode);
278 
279 	err = ext4_mark_iloc_dirty(handle, inode, &iloc);
280 flags_err:
281 	ext4_journal_stop(handle);
282 	if (err)
283 		goto flags_out;
284 
285 	if ((jflag ^ oldflags) & (EXT4_JOURNAL_DATA_FL))
286 		err = ext4_change_inode_journal_flag(inode, jflag);
287 	if (err)
288 		goto flags_out;
289 	if (migrate) {
290 		if (flags & EXT4_EXTENTS_FL)
291 			err = ext4_ext_migrate(inode);
292 		else
293 			err = ext4_ind_migrate(inode);
294 	}
295 
296 flags_out:
297 	return err;
298 }
299 
300 #ifdef CONFIG_QUOTA
301 static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
302 {
303 	struct inode *inode = file_inode(filp);
304 	struct super_block *sb = inode->i_sb;
305 	struct ext4_inode_info *ei = EXT4_I(inode);
306 	int err, rc;
307 	handle_t *handle;
308 	kprojid_t kprojid;
309 	struct ext4_iloc iloc;
310 	struct ext4_inode *raw_inode;
311 	struct dquot *transfer_to[MAXQUOTAS] = { };
312 
313 	if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
314 			EXT4_FEATURE_RO_COMPAT_PROJECT)) {
315 		if (projid != EXT4_DEF_PROJID)
316 			return -EOPNOTSUPP;
317 		else
318 			return 0;
319 	}
320 
321 	if (EXT4_INODE_SIZE(sb) <= EXT4_GOOD_OLD_INODE_SIZE)
322 		return -EOPNOTSUPP;
323 
324 	kprojid = make_kprojid(&init_user_ns, (projid_t)projid);
325 
326 	if (projid_eq(kprojid, EXT4_I(inode)->i_projid))
327 		return 0;
328 
329 	err = mnt_want_write_file(filp);
330 	if (err)
331 		return err;
332 
333 	err = -EPERM;
334 	inode_lock(inode);
335 	/* Is it quota file? Do not allow user to mess with it */
336 	if (IS_NOQUOTA(inode))
337 		goto out_unlock;
338 
339 	err = ext4_get_inode_loc(inode, &iloc);
340 	if (err)
341 		goto out_unlock;
342 
343 	raw_inode = ext4_raw_inode(&iloc);
344 	if (!EXT4_FITS_IN_INODE(raw_inode, ei, i_projid)) {
345 		err = -EOVERFLOW;
346 		brelse(iloc.bh);
347 		goto out_unlock;
348 	}
349 	brelse(iloc.bh);
350 
351 	dquot_initialize(inode);
352 
353 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
354 		EXT4_QUOTA_INIT_BLOCKS(sb) +
355 		EXT4_QUOTA_DEL_BLOCKS(sb) + 3);
356 	if (IS_ERR(handle)) {
357 		err = PTR_ERR(handle);
358 		goto out_unlock;
359 	}
360 
361 	err = ext4_reserve_inode_write(handle, inode, &iloc);
362 	if (err)
363 		goto out_stop;
364 
365 	transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
366 	if (!IS_ERR(transfer_to[PRJQUOTA])) {
367 		err = __dquot_transfer(inode, transfer_to);
368 		dqput(transfer_to[PRJQUOTA]);
369 		if (err)
370 			goto out_dirty;
371 	}
372 
373 	EXT4_I(inode)->i_projid = kprojid;
374 	inode->i_ctime = ext4_current_time(inode);
375 out_dirty:
376 	rc = ext4_mark_iloc_dirty(handle, inode, &iloc);
377 	if (!err)
378 		err = rc;
379 out_stop:
380 	ext4_journal_stop(handle);
381 out_unlock:
382 	inode_unlock(inode);
383 	mnt_drop_write_file(filp);
384 	return err;
385 }
386 #else
387 static int ext4_ioctl_setproject(struct file *filp, __u32 projid)
388 {
389 	if (projid != EXT4_DEF_PROJID)
390 		return -EOPNOTSUPP;
391 	return 0;
392 }
393 #endif
394 
395 /* Transfer internal flags to xflags */
396 static inline __u32 ext4_iflags_to_xflags(unsigned long iflags)
397 {
398 	__u32 xflags = 0;
399 
400 	if (iflags & EXT4_SYNC_FL)
401 		xflags |= FS_XFLAG_SYNC;
402 	if (iflags & EXT4_IMMUTABLE_FL)
403 		xflags |= FS_XFLAG_IMMUTABLE;
404 	if (iflags & EXT4_APPEND_FL)
405 		xflags |= FS_XFLAG_APPEND;
406 	if (iflags & EXT4_NODUMP_FL)
407 		xflags |= FS_XFLAG_NODUMP;
408 	if (iflags & EXT4_NOATIME_FL)
409 		xflags |= FS_XFLAG_NOATIME;
410 	if (iflags & EXT4_PROJINHERIT_FL)
411 		xflags |= FS_XFLAG_PROJINHERIT;
412 	return xflags;
413 }
414 
415 /* Transfer xflags flags to internal */
416 static inline unsigned long ext4_xflags_to_iflags(__u32 xflags)
417 {
418 	unsigned long iflags = 0;
419 
420 	if (xflags & FS_XFLAG_SYNC)
421 		iflags |= EXT4_SYNC_FL;
422 	if (xflags & FS_XFLAG_IMMUTABLE)
423 		iflags |= EXT4_IMMUTABLE_FL;
424 	if (xflags & FS_XFLAG_APPEND)
425 		iflags |= EXT4_APPEND_FL;
426 	if (xflags & FS_XFLAG_NODUMP)
427 		iflags |= EXT4_NODUMP_FL;
428 	if (xflags & FS_XFLAG_NOATIME)
429 		iflags |= EXT4_NOATIME_FL;
430 	if (xflags & FS_XFLAG_PROJINHERIT)
431 		iflags |= EXT4_PROJINHERIT_FL;
432 
433 	return iflags;
434 }
435 
436 long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
437 {
438 	struct inode *inode = file_inode(filp);
439 	struct super_block *sb = inode->i_sb;
440 	struct ext4_inode_info *ei = EXT4_I(inode);
441 	unsigned int flags;
442 
443 	ext4_debug("cmd = %u, arg = %lu\n", cmd, arg);
444 
445 	switch (cmd) {
446 	case EXT4_IOC_GETFLAGS:
447 		ext4_get_inode_flags(ei);
448 		flags = ei->i_flags & EXT4_FL_USER_VISIBLE;
449 		return put_user(flags, (int __user *) arg);
450 	case EXT4_IOC_SETFLAGS: {
451 		int err;
452 
453 		if (!inode_owner_or_capable(inode))
454 			return -EACCES;
455 
456 		if (get_user(flags, (int __user *) arg))
457 			return -EFAULT;
458 
459 		err = mnt_want_write_file(filp);
460 		if (err)
461 			return err;
462 
463 		flags = ext4_mask_flags(inode->i_mode, flags);
464 
465 		inode_lock(inode);
466 		err = ext4_ioctl_setflags(inode, flags);
467 		inode_unlock(inode);
468 		mnt_drop_write_file(filp);
469 		return err;
470 	}
471 	case EXT4_IOC_GETVERSION:
472 	case EXT4_IOC_GETVERSION_OLD:
473 		return put_user(inode->i_generation, (int __user *) arg);
474 	case EXT4_IOC_SETVERSION:
475 	case EXT4_IOC_SETVERSION_OLD: {
476 		handle_t *handle;
477 		struct ext4_iloc iloc;
478 		__u32 generation;
479 		int err;
480 
481 		if (!inode_owner_or_capable(inode))
482 			return -EPERM;
483 
484 		if (ext4_has_metadata_csum(inode->i_sb)) {
485 			ext4_warning(sb, "Setting inode version is not "
486 				     "supported with metadata_csum enabled.");
487 			return -ENOTTY;
488 		}
489 
490 		err = mnt_want_write_file(filp);
491 		if (err)
492 			return err;
493 		if (get_user(generation, (int __user *) arg)) {
494 			err = -EFAULT;
495 			goto setversion_out;
496 		}
497 
498 		inode_lock(inode);
499 		handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
500 		if (IS_ERR(handle)) {
501 			err = PTR_ERR(handle);
502 			goto unlock_out;
503 		}
504 		err = ext4_reserve_inode_write(handle, inode, &iloc);
505 		if (err == 0) {
506 			inode->i_ctime = ext4_current_time(inode);
507 			inode->i_generation = generation;
508 			err = ext4_mark_iloc_dirty(handle, inode, &iloc);
509 		}
510 		ext4_journal_stop(handle);
511 
512 unlock_out:
513 		inode_unlock(inode);
514 setversion_out:
515 		mnt_drop_write_file(filp);
516 		return err;
517 	}
518 	case EXT4_IOC_GROUP_EXTEND: {
519 		ext4_fsblk_t n_blocks_count;
520 		int err, err2=0;
521 
522 		err = ext4_resize_begin(sb);
523 		if (err)
524 			return err;
525 
526 		if (get_user(n_blocks_count, (__u32 __user *)arg)) {
527 			err = -EFAULT;
528 			goto group_extend_out;
529 		}
530 
531 		if (ext4_has_feature_bigalloc(sb)) {
532 			ext4_msg(sb, KERN_ERR,
533 				 "Online resizing not supported with bigalloc");
534 			err = -EOPNOTSUPP;
535 			goto group_extend_out;
536 		}
537 
538 		err = mnt_want_write_file(filp);
539 		if (err)
540 			goto group_extend_out;
541 
542 		err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
543 		if (EXT4_SB(sb)->s_journal) {
544 			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
545 			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
546 			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
547 		}
548 		if (err == 0)
549 			err = err2;
550 		mnt_drop_write_file(filp);
551 group_extend_out:
552 		ext4_resize_end(sb);
553 		return err;
554 	}
555 
556 	case EXT4_IOC_MOVE_EXT: {
557 		struct move_extent me;
558 		struct fd donor;
559 		int err;
560 
561 		if (!(filp->f_mode & FMODE_READ) ||
562 		    !(filp->f_mode & FMODE_WRITE))
563 			return -EBADF;
564 
565 		if (copy_from_user(&me,
566 			(struct move_extent __user *)arg, sizeof(me)))
567 			return -EFAULT;
568 		me.moved_len = 0;
569 
570 		donor = fdget(me.donor_fd);
571 		if (!donor.file)
572 			return -EBADF;
573 
574 		if (!(donor.file->f_mode & FMODE_WRITE)) {
575 			err = -EBADF;
576 			goto mext_out;
577 		}
578 
579 		if (ext4_has_feature_bigalloc(sb)) {
580 			ext4_msg(sb, KERN_ERR,
581 				 "Online defrag not supported with bigalloc");
582 			err = -EOPNOTSUPP;
583 			goto mext_out;
584 		} else if (IS_DAX(inode)) {
585 			ext4_msg(sb, KERN_ERR,
586 				 "Online defrag not supported with DAX");
587 			err = -EOPNOTSUPP;
588 			goto mext_out;
589 		}
590 
591 		err = mnt_want_write_file(filp);
592 		if (err)
593 			goto mext_out;
594 
595 		err = ext4_move_extents(filp, donor.file, me.orig_start,
596 					me.donor_start, me.len, &me.moved_len);
597 		mnt_drop_write_file(filp);
598 
599 		if (copy_to_user((struct move_extent __user *)arg,
600 				 &me, sizeof(me)))
601 			err = -EFAULT;
602 mext_out:
603 		fdput(donor);
604 		return err;
605 	}
606 
607 	case EXT4_IOC_GROUP_ADD: {
608 		struct ext4_new_group_data input;
609 		int err, err2=0;
610 
611 		err = ext4_resize_begin(sb);
612 		if (err)
613 			return err;
614 
615 		if (copy_from_user(&input, (struct ext4_new_group_input __user *)arg,
616 				sizeof(input))) {
617 			err = -EFAULT;
618 			goto group_add_out;
619 		}
620 
621 		if (ext4_has_feature_bigalloc(sb)) {
622 			ext4_msg(sb, KERN_ERR,
623 				 "Online resizing not supported with bigalloc");
624 			err = -EOPNOTSUPP;
625 			goto group_add_out;
626 		}
627 
628 		err = mnt_want_write_file(filp);
629 		if (err)
630 			goto group_add_out;
631 
632 		err = ext4_group_add(sb, &input);
633 		if (EXT4_SB(sb)->s_journal) {
634 			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
635 			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
636 			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
637 		}
638 		if (err == 0)
639 			err = err2;
640 		mnt_drop_write_file(filp);
641 		if (!err && ext4_has_group_desc_csum(sb) &&
642 		    test_opt(sb, INIT_INODE_TABLE))
643 			err = ext4_register_li_request(sb, input.group);
644 group_add_out:
645 		ext4_resize_end(sb);
646 		return err;
647 	}
648 
649 	case EXT4_IOC_MIGRATE:
650 	{
651 		int err;
652 		if (!inode_owner_or_capable(inode))
653 			return -EACCES;
654 
655 		err = mnt_want_write_file(filp);
656 		if (err)
657 			return err;
658 		/*
659 		 * inode_mutex prevent write and truncate on the file.
660 		 * Read still goes through. We take i_data_sem in
661 		 * ext4_ext_swap_inode_data before we switch the
662 		 * inode format to prevent read.
663 		 */
664 		inode_lock((inode));
665 		err = ext4_ext_migrate(inode);
666 		inode_unlock((inode));
667 		mnt_drop_write_file(filp);
668 		return err;
669 	}
670 
671 	case EXT4_IOC_ALLOC_DA_BLKS:
672 	{
673 		int err;
674 		if (!inode_owner_or_capable(inode))
675 			return -EACCES;
676 
677 		err = mnt_want_write_file(filp);
678 		if (err)
679 			return err;
680 		err = ext4_alloc_da_blocks(inode);
681 		mnt_drop_write_file(filp);
682 		return err;
683 	}
684 
685 	case EXT4_IOC_SWAP_BOOT:
686 	{
687 		int err;
688 		if (!(filp->f_mode & FMODE_WRITE))
689 			return -EBADF;
690 		err = mnt_want_write_file(filp);
691 		if (err)
692 			return err;
693 		err = swap_inode_boot_loader(sb, inode);
694 		mnt_drop_write_file(filp);
695 		return err;
696 	}
697 
698 	case EXT4_IOC_RESIZE_FS: {
699 		ext4_fsblk_t n_blocks_count;
700 		int err = 0, err2 = 0;
701 		ext4_group_t o_group = EXT4_SB(sb)->s_groups_count;
702 
703 		if (ext4_has_feature_bigalloc(sb)) {
704 			ext4_msg(sb, KERN_ERR,
705 				 "Online resizing not (yet) supported with bigalloc");
706 			return -EOPNOTSUPP;
707 		}
708 
709 		if (copy_from_user(&n_blocks_count, (__u64 __user *)arg,
710 				   sizeof(__u64))) {
711 			return -EFAULT;
712 		}
713 
714 		err = ext4_resize_begin(sb);
715 		if (err)
716 			return err;
717 
718 		err = mnt_want_write_file(filp);
719 		if (err)
720 			goto resizefs_out;
721 
722 		err = ext4_resize_fs(sb, n_blocks_count);
723 		if (EXT4_SB(sb)->s_journal) {
724 			jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
725 			err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
726 			jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
727 		}
728 		if (err == 0)
729 			err = err2;
730 		mnt_drop_write_file(filp);
731 		if (!err && (o_group > EXT4_SB(sb)->s_groups_count) &&
732 		    ext4_has_group_desc_csum(sb) &&
733 		    test_opt(sb, INIT_INODE_TABLE))
734 			err = ext4_register_li_request(sb, o_group);
735 
736 resizefs_out:
737 		ext4_resize_end(sb);
738 		return err;
739 	}
740 
741 	case FITRIM:
742 	{
743 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
744 		struct fstrim_range range;
745 		int ret = 0;
746 
747 		if (!capable(CAP_SYS_ADMIN))
748 			return -EPERM;
749 
750 		if (!blk_queue_discard(q))
751 			return -EOPNOTSUPP;
752 
753 		if (copy_from_user(&range, (struct fstrim_range __user *)arg,
754 		    sizeof(range)))
755 			return -EFAULT;
756 
757 		range.minlen = max((unsigned int)range.minlen,
758 				   q->limits.discard_granularity);
759 		ret = ext4_trim_fs(sb, &range);
760 		if (ret < 0)
761 			return ret;
762 
763 		if (copy_to_user((struct fstrim_range __user *)arg, &range,
764 		    sizeof(range)))
765 			return -EFAULT;
766 
767 		return 0;
768 	}
769 	case EXT4_IOC_PRECACHE_EXTENTS:
770 		return ext4_ext_precache(inode);
771 	case EXT4_IOC_SET_ENCRYPTION_POLICY: {
772 #ifdef CONFIG_EXT4_FS_ENCRYPTION
773 		struct fscrypt_policy policy;
774 
775 		if (copy_from_user(&policy,
776 				   (struct fscrypt_policy __user *)arg,
777 				   sizeof(policy)))
778 			return -EFAULT;
779 		return fscrypt_process_policy(inode, &policy);
780 #else
781 		return -EOPNOTSUPP;
782 #endif
783 	}
784 	case EXT4_IOC_GET_ENCRYPTION_PWSALT: {
785 		int err, err2;
786 		struct ext4_sb_info *sbi = EXT4_SB(sb);
787 		handle_t *handle;
788 
789 		if (!ext4_sb_has_crypto(sb))
790 			return -EOPNOTSUPP;
791 		if (uuid_is_zero(sbi->s_es->s_encrypt_pw_salt)) {
792 			err = mnt_want_write_file(filp);
793 			if (err)
794 				return err;
795 			handle = ext4_journal_start_sb(sb, EXT4_HT_MISC, 1);
796 			if (IS_ERR(handle)) {
797 				err = PTR_ERR(handle);
798 				goto pwsalt_err_exit;
799 			}
800 			err = ext4_journal_get_write_access(handle, sbi->s_sbh);
801 			if (err)
802 				goto pwsalt_err_journal;
803 			generate_random_uuid(sbi->s_es->s_encrypt_pw_salt);
804 			err = ext4_handle_dirty_metadata(handle, NULL,
805 							 sbi->s_sbh);
806 		pwsalt_err_journal:
807 			err2 = ext4_journal_stop(handle);
808 			if (err2 && !err)
809 				err = err2;
810 		pwsalt_err_exit:
811 			mnt_drop_write_file(filp);
812 			if (err)
813 				return err;
814 		}
815 		if (copy_to_user((void __user *) arg,
816 				 sbi->s_es->s_encrypt_pw_salt, 16))
817 			return -EFAULT;
818 		return 0;
819 	}
820 	case EXT4_IOC_GET_ENCRYPTION_POLICY: {
821 #ifdef CONFIG_EXT4_FS_ENCRYPTION
822 		struct fscrypt_policy policy;
823 		int err = 0;
824 
825 		if (!ext4_encrypted_inode(inode))
826 			return -ENOENT;
827 		err = fscrypt_get_policy(inode, &policy);
828 		if (err)
829 			return err;
830 		if (copy_to_user((void __user *)arg, &policy, sizeof(policy)))
831 			return -EFAULT;
832 		return 0;
833 #else
834 		return -EOPNOTSUPP;
835 #endif
836 	}
837 	case EXT4_IOC_FSGETXATTR:
838 	{
839 		struct fsxattr fa;
840 
841 		memset(&fa, 0, sizeof(struct fsxattr));
842 		ext4_get_inode_flags(ei);
843 		fa.fsx_xflags = ext4_iflags_to_xflags(ei->i_flags & EXT4_FL_USER_VISIBLE);
844 
845 		if (EXT4_HAS_RO_COMPAT_FEATURE(inode->i_sb,
846 				EXT4_FEATURE_RO_COMPAT_PROJECT)) {
847 			fa.fsx_projid = (__u32)from_kprojid(&init_user_ns,
848 				EXT4_I(inode)->i_projid);
849 		}
850 
851 		if (copy_to_user((struct fsxattr __user *)arg,
852 				 &fa, sizeof(fa)))
853 			return -EFAULT;
854 		return 0;
855 	}
856 	case EXT4_IOC_FSSETXATTR:
857 	{
858 		struct fsxattr fa;
859 		int err;
860 
861 		if (copy_from_user(&fa, (struct fsxattr __user *)arg,
862 				   sizeof(fa)))
863 			return -EFAULT;
864 
865 		/* Make sure caller has proper permission */
866 		if (!inode_owner_or_capable(inode))
867 			return -EACCES;
868 
869 		err = mnt_want_write_file(filp);
870 		if (err)
871 			return err;
872 
873 		flags = ext4_xflags_to_iflags(fa.fsx_xflags);
874 		flags = ext4_mask_flags(inode->i_mode, flags);
875 
876 		inode_lock(inode);
877 		flags = (ei->i_flags & ~EXT4_FL_XFLAG_VISIBLE) |
878 			 (flags & EXT4_FL_XFLAG_VISIBLE);
879 		err = ext4_ioctl_setflags(inode, flags);
880 		inode_unlock(inode);
881 		mnt_drop_write_file(filp);
882 		if (err)
883 			return err;
884 
885 		err = ext4_ioctl_setproject(filp, fa.fsx_projid);
886 		if (err)
887 			return err;
888 
889 		return 0;
890 	}
891 	default:
892 		return -ENOTTY;
893 	}
894 }
895 
896 #ifdef CONFIG_COMPAT
897 long ext4_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
898 {
899 	/* These are just misnamed, they actually get/put from/to user an int */
900 	switch (cmd) {
901 	case EXT4_IOC32_GETFLAGS:
902 		cmd = EXT4_IOC_GETFLAGS;
903 		break;
904 	case EXT4_IOC32_SETFLAGS:
905 		cmd = EXT4_IOC_SETFLAGS;
906 		break;
907 	case EXT4_IOC32_GETVERSION:
908 		cmd = EXT4_IOC_GETVERSION;
909 		break;
910 	case EXT4_IOC32_SETVERSION:
911 		cmd = EXT4_IOC_SETVERSION;
912 		break;
913 	case EXT4_IOC32_GROUP_EXTEND:
914 		cmd = EXT4_IOC_GROUP_EXTEND;
915 		break;
916 	case EXT4_IOC32_GETVERSION_OLD:
917 		cmd = EXT4_IOC_GETVERSION_OLD;
918 		break;
919 	case EXT4_IOC32_SETVERSION_OLD:
920 		cmd = EXT4_IOC_SETVERSION_OLD;
921 		break;
922 	case EXT4_IOC32_GETRSVSZ:
923 		cmd = EXT4_IOC_GETRSVSZ;
924 		break;
925 	case EXT4_IOC32_SETRSVSZ:
926 		cmd = EXT4_IOC_SETRSVSZ;
927 		break;
928 	case EXT4_IOC32_GROUP_ADD: {
929 		struct compat_ext4_new_group_input __user *uinput;
930 		struct ext4_new_group_input input;
931 		mm_segment_t old_fs;
932 		int err;
933 
934 		uinput = compat_ptr(arg);
935 		err = get_user(input.group, &uinput->group);
936 		err |= get_user(input.block_bitmap, &uinput->block_bitmap);
937 		err |= get_user(input.inode_bitmap, &uinput->inode_bitmap);
938 		err |= get_user(input.inode_table, &uinput->inode_table);
939 		err |= get_user(input.blocks_count, &uinput->blocks_count);
940 		err |= get_user(input.reserved_blocks,
941 				&uinput->reserved_blocks);
942 		if (err)
943 			return -EFAULT;
944 		old_fs = get_fs();
945 		set_fs(KERNEL_DS);
946 		err = ext4_ioctl(file, EXT4_IOC_GROUP_ADD,
947 				 (unsigned long) &input);
948 		set_fs(old_fs);
949 		return err;
950 	}
951 	case EXT4_IOC_MOVE_EXT:
952 	case EXT4_IOC_RESIZE_FS:
953 	case EXT4_IOC_PRECACHE_EXTENTS:
954 	case EXT4_IOC_SET_ENCRYPTION_POLICY:
955 	case EXT4_IOC_GET_ENCRYPTION_PWSALT:
956 	case EXT4_IOC_GET_ENCRYPTION_POLICY:
957 		break;
958 	default:
959 		return -ENOIOCTLCMD;
960 	}
961 	return ext4_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
962 }
963 #endif
964