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1/*
2 * linux/fs/ioctl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/syscalls.h>
8#include <linux/mm.h>
9#include <linux/capability.h>
10#include <linux/file.h>
11#include <linux/fs.h>
12#include <linux/security.h>
13#include <linux/export.h>
14#include <linux/uaccess.h>
15#include <linux/writeback.h>
16#include <linux/buffer_head.h>
17#include <linux/falloc.h>
18#include "internal.h"
19
20#include <asm/ioctls.h>
21
22/* So that the fiemap access checks can't overflow on 32 bit machines. */
23#define FIEMAP_MAX_EXTENTS (UINT_MAX / sizeof(struct fiemap_extent))
24
25/**
26 * vfs_ioctl - call filesystem specific ioctl methods
27 * @filp: open file to invoke ioctl method on
28 * @cmd: ioctl command to execute
29 * @arg: command-specific argument for ioctl
30 *
31 * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
32 * returns -ENOTTY.
33 *
34 * Returns 0 on success, -errno on error.
35 */
36long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
37{
38 int error = -ENOTTY;
39
40 if (!filp->f_op->unlocked_ioctl)
41 goto out;
42
43 error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
44 if (error == -ENOIOCTLCMD)
45 error = -ENOTTY;
46 out:
47 return error;
48}
49
50static int ioctl_fibmap(struct file *filp, int __user *p)
51{
52 struct address_space *mapping = filp->f_mapping;
53 int res, block;
54
55 /* do we support this mess? */
56 if (!mapping->a_ops->bmap)
57 return -EINVAL;
58 if (!capable(CAP_SYS_RAWIO))
59 return -EPERM;
60 res = get_user(block, p);
61 if (res)
62 return res;
63 res = mapping->a_ops->bmap(mapping, block);
64 return put_user(res, p);
65}
66
67/**
68 * fiemap_fill_next_extent - Fiemap helper function
69 * @fieinfo: Fiemap context passed into ->fiemap
70 * @logical: Extent logical start offset, in bytes
71 * @phys: Extent physical start offset, in bytes
72 * @len: Extent length, in bytes
73 * @flags: FIEMAP_EXTENT flags that describe this extent
74 *
75 * Called from file system ->fiemap callback. Will populate extent
76 * info as passed in via arguments and copy to user memory. On
77 * success, extent count on fieinfo is incremented.
78 *
79 * Returns 0 on success, -errno on error, 1 if this was the last
80 * extent that will fit in user array.
81 */
82#define SET_UNKNOWN_FLAGS (FIEMAP_EXTENT_DELALLOC)
83#define SET_NO_UNMOUNTED_IO_FLAGS (FIEMAP_EXTENT_DATA_ENCRYPTED)
84#define SET_NOT_ALIGNED_FLAGS (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
85int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
86 u64 phys, u64 len, u32 flags)
87{
88 struct fiemap_extent extent;
89 struct fiemap_extent __user *dest = fieinfo->fi_extents_start;
90
91 /* only count the extents */
92 if (fieinfo->fi_extents_max == 0) {
93 fieinfo->fi_extents_mapped++;
94 return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
95 }
96
97 if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
98 return 1;
99
100 if (flags & SET_UNKNOWN_FLAGS)
101 flags |= FIEMAP_EXTENT_UNKNOWN;
102 if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
103 flags |= FIEMAP_EXTENT_ENCODED;
104 if (flags & SET_NOT_ALIGNED_FLAGS)
105 flags |= FIEMAP_EXTENT_NOT_ALIGNED;
106
107 memset(&extent, 0, sizeof(extent));
108 extent.fe_logical = logical;
109 extent.fe_physical = phys;
110 extent.fe_length = len;
111 extent.fe_flags = flags;
112
113 dest += fieinfo->fi_extents_mapped;
114 if (copy_to_user(dest, &extent, sizeof(extent)))
115 return -EFAULT;
116
117 fieinfo->fi_extents_mapped++;
118 if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
119 return 1;
120 return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
121}
122EXPORT_SYMBOL(fiemap_fill_next_extent);
123
124/**
125 * fiemap_check_flags - check validity of requested flags for fiemap
126 * @fieinfo: Fiemap context passed into ->fiemap
127 * @fs_flags: Set of fiemap flags that the file system understands
128 *
129 * Called from file system ->fiemap callback. This will compute the
130 * intersection of valid fiemap flags and those that the fs supports. That
131 * value is then compared against the user supplied flags. In case of bad user
132 * flags, the invalid values will be written into the fieinfo structure, and
133 * -EBADR is returned, which tells ioctl_fiemap() to return those values to
134 * userspace. For this reason, a return code of -EBADR should be preserved.
135 *
136 * Returns 0 on success, -EBADR on bad flags.
137 */
138int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags)
139{
140 u32 incompat_flags;
141
142 incompat_flags = fieinfo->fi_flags & ~(FIEMAP_FLAGS_COMPAT & fs_flags);
143 if (incompat_flags) {
144 fieinfo->fi_flags = incompat_flags;
145 return -EBADR;
146 }
147 return 0;
148}
149EXPORT_SYMBOL(fiemap_check_flags);
150
151static int fiemap_check_ranges(struct super_block *sb,
152 u64 start, u64 len, u64 *new_len)
153{
154 u64 maxbytes = (u64) sb->s_maxbytes;
155
156 *new_len = len;
157
158 if (len == 0)
159 return -EINVAL;
160
161 if (start > maxbytes)
162 return -EFBIG;
163
164 /*
165 * Shrink request scope to what the fs can actually handle.
166 */
167 if (len > maxbytes || (maxbytes - len) < start)
168 *new_len = maxbytes - start;
169
170 return 0;
171}
172
173static int ioctl_fiemap(struct file *filp, unsigned long arg)
174{
175 struct fiemap fiemap;
176 struct fiemap __user *ufiemap = (struct fiemap __user *) arg;
177 struct fiemap_extent_info fieinfo = { 0, };
178 struct inode *inode = file_inode(filp);
179 struct super_block *sb = inode->i_sb;
180 u64 len;
181 int error;
182
183 if (!inode->i_op->fiemap)
184 return -EOPNOTSUPP;
185
186 if (copy_from_user(&fiemap, ufiemap, sizeof(fiemap)))
187 return -EFAULT;
188
189 if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
190 return -EINVAL;
191
192 error = fiemap_check_ranges(sb, fiemap.fm_start, fiemap.fm_length,
193 &len);
194 if (error)
195 return error;
196
197 fieinfo.fi_flags = fiemap.fm_flags;
198 fieinfo.fi_extents_max = fiemap.fm_extent_count;
199 fieinfo.fi_extents_start = ufiemap->fm_extents;
200
201 if (fiemap.fm_extent_count != 0 &&
202 !access_ok(VERIFY_WRITE, fieinfo.fi_extents_start,
203 fieinfo.fi_extents_max * sizeof(struct fiemap_extent)))
204 return -EFAULT;
205
206 if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
207 filemap_write_and_wait(inode->i_mapping);
208
209 error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, len);
210 fiemap.fm_flags = fieinfo.fi_flags;
211 fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
212 if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap)))
213 error = -EFAULT;
214
215 return error;
216}
217
218static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
219 u64 off, u64 olen, u64 destoff)
220{
221 struct fd src_file = fdget(srcfd);
222 int ret;
223
224 if (!src_file.file)
225 return -EBADF;
226 ret = -EXDEV;
227 if (src_file.file->f_path.mnt != dst_file->f_path.mnt)
228 goto fdput;
229 ret = do_clone_file_range(src_file.file, off, dst_file, destoff, olen);
230fdput:
231 fdput(src_file);
232 return ret;
233}
234
235static long ioctl_file_clone_range(struct file *file, void __user *argp)
236{
237 struct file_clone_range args;
238
239 if (copy_from_user(&args, argp, sizeof(args)))
240 return -EFAULT;
241 return ioctl_file_clone(file, args.src_fd, args.src_offset,
242 args.src_length, args.dest_offset);
243}
244
245#ifdef CONFIG_BLOCK
246
247static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
248{
249 return (offset >> inode->i_blkbits);
250}
251
252static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
253{
254 return (blk << inode->i_blkbits);
255}
256
257/**
258 * __generic_block_fiemap - FIEMAP for block based inodes (no locking)
259 * @inode: the inode to map
260 * @fieinfo: the fiemap info struct that will be passed back to userspace
261 * @start: where to start mapping in the inode
262 * @len: how much space to map
263 * @get_block: the fs's get_block function
264 *
265 * This does FIEMAP for block based inodes. Basically it will just loop
266 * through get_block until we hit the number of extents we want to map, or we
267 * go past the end of the file and hit a hole.
268 *
269 * If it is possible to have data blocks beyond a hole past @inode->i_size, then
270 * please do not use this function, it will stop at the first unmapped block
271 * beyond i_size.
272 *
273 * If you use this function directly, you need to do your own locking. Use
274 * generic_block_fiemap if you want the locking done for you.
275 */
276
277int __generic_block_fiemap(struct inode *inode,
278 struct fiemap_extent_info *fieinfo, loff_t start,
279 loff_t len, get_block_t *get_block)
280{
281 struct buffer_head map_bh;
282 sector_t start_blk, last_blk;
283 loff_t isize = i_size_read(inode);
284 u64 logical = 0, phys = 0, size = 0;
285 u32 flags = FIEMAP_EXTENT_MERGED;
286 bool past_eof = false, whole_file = false;
287 int ret = 0;
288
289 ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
290 if (ret)
291 return ret;
292
293 /*
294 * Either the i_mutex or other appropriate locking needs to be held
295 * since we expect isize to not change at all through the duration of
296 * this call.
297 */
298 if (len >= isize) {
299 whole_file = true;
300 len = isize;
301 }
302
303 /*
304 * Some filesystems can't deal with being asked to map less than
305 * blocksize, so make sure our len is at least block length.
306 */
307 if (logical_to_blk(inode, len) == 0)
308 len = blk_to_logical(inode, 1);
309
310 start_blk = logical_to_blk(inode, start);
311 last_blk = logical_to_blk(inode, start + len - 1);
312
313 do {
314 /*
315 * we set b_size to the total size we want so it will map as
316 * many contiguous blocks as possible at once
317 */
318 memset(&map_bh, 0, sizeof(struct buffer_head));
319 map_bh.b_size = len;
320
321 ret = get_block(inode, start_blk, &map_bh, 0);
322 if (ret)
323 break;
324
325 /* HOLE */
326 if (!buffer_mapped(&map_bh)) {
327 start_blk++;
328
329 /*
330 * We want to handle the case where there is an
331 * allocated block at the front of the file, and then
332 * nothing but holes up to the end of the file properly,
333 * to make sure that extent at the front gets properly
334 * marked with FIEMAP_EXTENT_LAST
335 */
336 if (!past_eof &&
337 blk_to_logical(inode, start_blk) >= isize)
338 past_eof = 1;
339
340 /*
341 * First hole after going past the EOF, this is our
342 * last extent
343 */
344 if (past_eof && size) {
345 flags = FIEMAP_EXTENT_MERGED|FIEMAP_EXTENT_LAST;
346 ret = fiemap_fill_next_extent(fieinfo, logical,
347 phys, size,
348 flags);
349 } else if (size) {
350 ret = fiemap_fill_next_extent(fieinfo, logical,
351 phys, size, flags);
352 size = 0;
353 }
354
355 /* if we have holes up to/past EOF then we're done */
356 if (start_blk > last_blk || past_eof || ret)
357 break;
358 } else {
359 /*
360 * We have gone over the length of what we wanted to
361 * map, and it wasn't the entire file, so add the extent
362 * we got last time and exit.
363 *
364 * This is for the case where say we want to map all the
365 * way up to the second to the last block in a file, but
366 * the last block is a hole, making the second to last
367 * block FIEMAP_EXTENT_LAST. In this case we want to
368 * see if there is a hole after the second to last block
369 * so we can mark it properly. If we found data after
370 * we exceeded the length we were requesting, then we
371 * are good to go, just add the extent to the fieinfo
372 * and break
373 */
374 if (start_blk > last_blk && !whole_file) {
375 ret = fiemap_fill_next_extent(fieinfo, logical,
376 phys, size,
377 flags);
378 break;
379 }
380
381 /*
382 * if size != 0 then we know we already have an extent
383 * to add, so add it.
384 */
385 if (size) {
386 ret = fiemap_fill_next_extent(fieinfo, logical,
387 phys, size,
388 flags);
389 if (ret)
390 break;
391 }
392
393 logical = blk_to_logical(inode, start_blk);
394 phys = blk_to_logical(inode, map_bh.b_blocknr);
395 size = map_bh.b_size;
396 flags = FIEMAP_EXTENT_MERGED;
397
398 start_blk += logical_to_blk(inode, size);
399
400 /*
401 * If we are past the EOF, then we need to make sure as
402 * soon as we find a hole that the last extent we found
403 * is marked with FIEMAP_EXTENT_LAST
404 */
405 if (!past_eof && logical + size >= isize)
406 past_eof = true;
407 }
408 cond_resched();
409 if (fatal_signal_pending(current)) {
410 ret = -EINTR;
411 break;
412 }
413
414 } while (1);
415
416 /* If ret is 1 then we just hit the end of the extent array */
417 if (ret == 1)
418 ret = 0;
419
420 return ret;
421}
422EXPORT_SYMBOL(__generic_block_fiemap);
423
424/**
425 * generic_block_fiemap - FIEMAP for block based inodes
426 * @inode: The inode to map
427 * @fieinfo: The mapping information
428 * @start: The initial block to map
429 * @len: The length of the extect to attempt to map
430 * @get_block: The block mapping function for the fs
431 *
432 * Calls __generic_block_fiemap to map the inode, after taking
433 * the inode's mutex lock.
434 */
435
436int generic_block_fiemap(struct inode *inode,
437 struct fiemap_extent_info *fieinfo, u64 start,
438 u64 len, get_block_t *get_block)
439{
440 int ret;
441 inode_lock(inode);
442 ret = __generic_block_fiemap(inode, fieinfo, start, len, get_block);
443 inode_unlock(inode);
444 return ret;
445}
446EXPORT_SYMBOL(generic_block_fiemap);
447
448#endif /* CONFIG_BLOCK */
449
450/*
451 * This provides compatibility with legacy XFS pre-allocation ioctls
452 * which predate the fallocate syscall.
453 *
454 * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
455 * are used here, rest are ignored.
456 */
457int ioctl_preallocate(struct file *filp, void __user *argp)
458{
459 struct inode *inode = file_inode(filp);
460 struct space_resv sr;
461
462 if (copy_from_user(&sr, argp, sizeof(sr)))
463 return -EFAULT;
464
465 switch (sr.l_whence) {
466 case SEEK_SET:
467 break;
468 case SEEK_CUR:
469 sr.l_start += filp->f_pos;
470 break;
471 case SEEK_END:
472 sr.l_start += i_size_read(inode);
473 break;
474 default:
475 return -EINVAL;
476 }
477
478 return vfs_fallocate(filp, FALLOC_FL_KEEP_SIZE, sr.l_start, sr.l_len);
479}
480
481static int file_ioctl(struct file *filp, unsigned int cmd,
482 unsigned long arg)
483{
484 struct inode *inode = file_inode(filp);
485 int __user *p = (int __user *)arg;
486
487 switch (cmd) {
488 case FIBMAP:
489 return ioctl_fibmap(filp, p);
490 case FIONREAD:
491 return put_user(i_size_read(inode) - filp->f_pos, p);
492 case FS_IOC_RESVSP:
493 case FS_IOC_RESVSP64:
494 return ioctl_preallocate(filp, p);
495 }
496
497 return vfs_ioctl(filp, cmd, arg);
498}
499
500static int ioctl_fionbio(struct file *filp, int __user *argp)
501{
502 unsigned int flag;
503 int on, error;
504
505 error = get_user(on, argp);
506 if (error)
507 return error;
508 flag = O_NONBLOCK;
509#ifdef __sparc__
510 /* SunOS compatibility item. */
511 if (O_NONBLOCK != O_NDELAY)
512 flag |= O_NDELAY;
513#endif
514 spin_lock(&filp->f_lock);
515 if (on)
516 filp->f_flags |= flag;
517 else
518 filp->f_flags &= ~flag;
519 spin_unlock(&filp->f_lock);
520 return error;
521}
522
523static int ioctl_fioasync(unsigned int fd, struct file *filp,
524 int __user *argp)
525{
526 unsigned int flag;
527 int on, error;
528
529 error = get_user(on, argp);
530 if (error)
531 return error;
532 flag = on ? FASYNC : 0;
533
534 /* Did FASYNC state change ? */
535 if ((flag ^ filp->f_flags) & FASYNC) {
536 if (filp->f_op->fasync)
537 /* fasync() adjusts filp->f_flags */
538 error = filp->f_op->fasync(fd, filp, on);
539 else
540 error = -ENOTTY;
541 }
542 return error < 0 ? error : 0;
543}
544
545static int ioctl_fsfreeze(struct file *filp)
546{
547 struct super_block *sb = file_inode(filp)->i_sb;
548
549 if (!capable(CAP_SYS_ADMIN))
550 return -EPERM;
551
552 /* If filesystem doesn't support freeze feature, return. */
553 if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
554 return -EOPNOTSUPP;
555
556 /* Freeze */
557 if (sb->s_op->freeze_super)
558 return sb->s_op->freeze_super(sb);
559 return freeze_super(sb);
560}
561
562static int ioctl_fsthaw(struct file *filp)
563{
564 struct super_block *sb = file_inode(filp)->i_sb;
565
566 if (!capable(CAP_SYS_ADMIN))
567 return -EPERM;
568
569 /* Thaw */
570 if (sb->s_op->thaw_super)
571 return sb->s_op->thaw_super(sb);
572 return thaw_super(sb);
573}
574
575static int ioctl_file_dedupe_range(struct file *file, void __user *arg)
576{
577 struct file_dedupe_range __user *argp = arg;
578 struct file_dedupe_range *same = NULL;
579 int ret;
580 unsigned long size;
581 u16 count;
582
583 if (get_user(count, &argp->dest_count)) {
584 ret = -EFAULT;
585 goto out;
586 }
587
588 size = offsetof(struct file_dedupe_range __user, info[count]);
589 if (size > PAGE_SIZE) {
590 ret = -ENOMEM;
591 goto out;
592 }
593
594 same = memdup_user(argp, size);
595 if (IS_ERR(same)) {
596 ret = PTR_ERR(same);
597 same = NULL;
598 goto out;
599 }
600
601 same->dest_count = count;
602 ret = vfs_dedupe_file_range(file, same);
603 if (ret)
604 goto out;
605
606 ret = copy_to_user(argp, same, size);
607 if (ret)
608 ret = -EFAULT;
609
610out:
611 kfree(same);
612 return ret;
613}
614
615/*
616 * When you add any new common ioctls to the switches above and below
617 * please update compat_sys_ioctl() too.
618 *
619 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
620 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
621 */
622int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
623 unsigned long arg)
624{
625 int error = 0;
626 int __user *argp = (int __user *)arg;
627 struct inode *inode = file_inode(filp);
628
629 switch (cmd) {
630 case FIOCLEX:
631 set_close_on_exec(fd, 1);
632 break;
633
634 case FIONCLEX:
635 set_close_on_exec(fd, 0);
636 break;
637
638 case FIONBIO:
639 error = ioctl_fionbio(filp, argp);
640 break;
641
642 case FIOASYNC:
643 error = ioctl_fioasync(fd, filp, argp);
644 break;
645
646 case FIOQSIZE:
647 if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
648 S_ISLNK(inode->i_mode)) {
649 loff_t res = inode_get_bytes(inode);
650 error = copy_to_user(argp, &res, sizeof(res)) ?
651 -EFAULT : 0;
652 } else
653 error = -ENOTTY;
654 break;
655
656 case FIFREEZE:
657 error = ioctl_fsfreeze(filp);
658 break;
659
660 case FITHAW:
661 error = ioctl_fsthaw(filp);
662 break;
663
664 case FS_IOC_FIEMAP:
665 return ioctl_fiemap(filp, arg);
666
667 case FIGETBSZ:
668 return put_user(inode->i_sb->s_blocksize, argp);
669
670 case FICLONE:
671 return ioctl_file_clone(filp, arg, 0, 0, 0);
672
673 case FICLONERANGE:
674 return ioctl_file_clone_range(filp, argp);
675
676 case FIDEDUPERANGE:
677 return ioctl_file_dedupe_range(filp, argp);
678
679 default:
680 if (S_ISREG(inode->i_mode))
681 error = file_ioctl(filp, cmd, arg);
682 else
683 error = vfs_ioctl(filp, cmd, arg);
684 break;
685 }
686 return error;
687}
688
689SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
690{
691 int error;
692 struct fd f = fdget(fd);
693
694 if (!f.file)
695 return -EBADF;
696 error = security_file_ioctl(f.file, cmd, arg);
697 if (!error)
698 error = do_vfs_ioctl(f.file, fd, cmd, arg);
699 fdput(f);
700 return error;
701}
1/*
2 * linux/fs/ioctl.c
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 */
6
7#include <linux/syscalls.h>
8#include <linux/mm.h>
9#include <linux/capability.h>
10#include <linux/file.h>
11#include <linux/fs.h>
12#include <linux/security.h>
13#include <linux/module.h>
14#include <linux/uaccess.h>
15#include <linux/writeback.h>
16#include <linux/buffer_head.h>
17#include <linux/falloc.h>
18
19#include <asm/ioctls.h>
20
21/* So that the fiemap access checks can't overflow on 32 bit machines. */
22#define FIEMAP_MAX_EXTENTS (UINT_MAX / sizeof(struct fiemap_extent))
23
24/**
25 * vfs_ioctl - call filesystem specific ioctl methods
26 * @filp: open file to invoke ioctl method on
27 * @cmd: ioctl command to execute
28 * @arg: command-specific argument for ioctl
29 *
30 * Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
31 * returns -ENOTTY.
32 *
33 * Returns 0 on success, -errno on error.
34 */
35static long vfs_ioctl(struct file *filp, unsigned int cmd,
36 unsigned long arg)
37{
38 int error = -ENOTTY;
39
40 if (!filp->f_op || !filp->f_op->unlocked_ioctl)
41 goto out;
42
43 error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
44 if (error == -ENOIOCTLCMD)
45 error = -EINVAL;
46 out:
47 return error;
48}
49
50static int ioctl_fibmap(struct file *filp, int __user *p)
51{
52 struct address_space *mapping = filp->f_mapping;
53 int res, block;
54
55 /* do we support this mess? */
56 if (!mapping->a_ops->bmap)
57 return -EINVAL;
58 if (!capable(CAP_SYS_RAWIO))
59 return -EPERM;
60 res = get_user(block, p);
61 if (res)
62 return res;
63 res = mapping->a_ops->bmap(mapping, block);
64 return put_user(res, p);
65}
66
67/**
68 * fiemap_fill_next_extent - Fiemap helper function
69 * @fieinfo: Fiemap context passed into ->fiemap
70 * @logical: Extent logical start offset, in bytes
71 * @phys: Extent physical start offset, in bytes
72 * @len: Extent length, in bytes
73 * @flags: FIEMAP_EXTENT flags that describe this extent
74 *
75 * Called from file system ->fiemap callback. Will populate extent
76 * info as passed in via arguments and copy to user memory. On
77 * success, extent count on fieinfo is incremented.
78 *
79 * Returns 0 on success, -errno on error, 1 if this was the last
80 * extent that will fit in user array.
81 */
82#define SET_UNKNOWN_FLAGS (FIEMAP_EXTENT_DELALLOC)
83#define SET_NO_UNMOUNTED_IO_FLAGS (FIEMAP_EXTENT_DATA_ENCRYPTED)
84#define SET_NOT_ALIGNED_FLAGS (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
85int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
86 u64 phys, u64 len, u32 flags)
87{
88 struct fiemap_extent extent;
89 struct fiemap_extent __user *dest = fieinfo->fi_extents_start;
90
91 /* only count the extents */
92 if (fieinfo->fi_extents_max == 0) {
93 fieinfo->fi_extents_mapped++;
94 return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
95 }
96
97 if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
98 return 1;
99
100 if (flags & SET_UNKNOWN_FLAGS)
101 flags |= FIEMAP_EXTENT_UNKNOWN;
102 if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
103 flags |= FIEMAP_EXTENT_ENCODED;
104 if (flags & SET_NOT_ALIGNED_FLAGS)
105 flags |= FIEMAP_EXTENT_NOT_ALIGNED;
106
107 memset(&extent, 0, sizeof(extent));
108 extent.fe_logical = logical;
109 extent.fe_physical = phys;
110 extent.fe_length = len;
111 extent.fe_flags = flags;
112
113 dest += fieinfo->fi_extents_mapped;
114 if (copy_to_user(dest, &extent, sizeof(extent)))
115 return -EFAULT;
116
117 fieinfo->fi_extents_mapped++;
118 if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
119 return 1;
120 return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
121}
122EXPORT_SYMBOL(fiemap_fill_next_extent);
123
124/**
125 * fiemap_check_flags - check validity of requested flags for fiemap
126 * @fieinfo: Fiemap context passed into ->fiemap
127 * @fs_flags: Set of fiemap flags that the file system understands
128 *
129 * Called from file system ->fiemap callback. This will compute the
130 * intersection of valid fiemap flags and those that the fs supports. That
131 * value is then compared against the user supplied flags. In case of bad user
132 * flags, the invalid values will be written into the fieinfo structure, and
133 * -EBADR is returned, which tells ioctl_fiemap() to return those values to
134 * userspace. For this reason, a return code of -EBADR should be preserved.
135 *
136 * Returns 0 on success, -EBADR on bad flags.
137 */
138int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags)
139{
140 u32 incompat_flags;
141
142 incompat_flags = fieinfo->fi_flags & ~(FIEMAP_FLAGS_COMPAT & fs_flags);
143 if (incompat_flags) {
144 fieinfo->fi_flags = incompat_flags;
145 return -EBADR;
146 }
147 return 0;
148}
149EXPORT_SYMBOL(fiemap_check_flags);
150
151static int fiemap_check_ranges(struct super_block *sb,
152 u64 start, u64 len, u64 *new_len)
153{
154 u64 maxbytes = (u64) sb->s_maxbytes;
155
156 *new_len = len;
157
158 if (len == 0)
159 return -EINVAL;
160
161 if (start > maxbytes)
162 return -EFBIG;
163
164 /*
165 * Shrink request scope to what the fs can actually handle.
166 */
167 if (len > maxbytes || (maxbytes - len) < start)
168 *new_len = maxbytes - start;
169
170 return 0;
171}
172
173static int ioctl_fiemap(struct file *filp, unsigned long arg)
174{
175 struct fiemap fiemap;
176 struct fiemap __user *ufiemap = (struct fiemap __user *) arg;
177 struct fiemap_extent_info fieinfo = { 0, };
178 struct inode *inode = filp->f_path.dentry->d_inode;
179 struct super_block *sb = inode->i_sb;
180 u64 len;
181 int error;
182
183 if (!inode->i_op->fiemap)
184 return -EOPNOTSUPP;
185
186 if (copy_from_user(&fiemap, ufiemap, sizeof(fiemap)))
187 return -EFAULT;
188
189 if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
190 return -EINVAL;
191
192 error = fiemap_check_ranges(sb, fiemap.fm_start, fiemap.fm_length,
193 &len);
194 if (error)
195 return error;
196
197 fieinfo.fi_flags = fiemap.fm_flags;
198 fieinfo.fi_extents_max = fiemap.fm_extent_count;
199 fieinfo.fi_extents_start = ufiemap->fm_extents;
200
201 if (fiemap.fm_extent_count != 0 &&
202 !access_ok(VERIFY_WRITE, fieinfo.fi_extents_start,
203 fieinfo.fi_extents_max * sizeof(struct fiemap_extent)))
204 return -EFAULT;
205
206 if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC)
207 filemap_write_and_wait(inode->i_mapping);
208
209 error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, len);
210 fiemap.fm_flags = fieinfo.fi_flags;
211 fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped;
212 if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap)))
213 error = -EFAULT;
214
215 return error;
216}
217
218#ifdef CONFIG_BLOCK
219
220static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
221{
222 return (offset >> inode->i_blkbits);
223}
224
225static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
226{
227 return (blk << inode->i_blkbits);
228}
229
230/**
231 * __generic_block_fiemap - FIEMAP for block based inodes (no locking)
232 * @inode: the inode to map
233 * @fieinfo: the fiemap info struct that will be passed back to userspace
234 * @start: where to start mapping in the inode
235 * @len: how much space to map
236 * @get_block: the fs's get_block function
237 *
238 * This does FIEMAP for block based inodes. Basically it will just loop
239 * through get_block until we hit the number of extents we want to map, or we
240 * go past the end of the file and hit a hole.
241 *
242 * If it is possible to have data blocks beyond a hole past @inode->i_size, then
243 * please do not use this function, it will stop at the first unmapped block
244 * beyond i_size.
245 *
246 * If you use this function directly, you need to do your own locking. Use
247 * generic_block_fiemap if you want the locking done for you.
248 */
249
250int __generic_block_fiemap(struct inode *inode,
251 struct fiemap_extent_info *fieinfo, loff_t start,
252 loff_t len, get_block_t *get_block)
253{
254 struct buffer_head map_bh;
255 sector_t start_blk, last_blk;
256 loff_t isize = i_size_read(inode);
257 u64 logical = 0, phys = 0, size = 0;
258 u32 flags = FIEMAP_EXTENT_MERGED;
259 bool past_eof = false, whole_file = false;
260 int ret = 0;
261
262 ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
263 if (ret)
264 return ret;
265
266 /*
267 * Either the i_mutex or other appropriate locking needs to be held
268 * since we expect isize to not change at all through the duration of
269 * this call.
270 */
271 if (len >= isize) {
272 whole_file = true;
273 len = isize;
274 }
275
276 /*
277 * Some filesystems can't deal with being asked to map less than
278 * blocksize, so make sure our len is at least block length.
279 */
280 if (logical_to_blk(inode, len) == 0)
281 len = blk_to_logical(inode, 1);
282
283 start_blk = logical_to_blk(inode, start);
284 last_blk = logical_to_blk(inode, start + len - 1);
285
286 do {
287 /*
288 * we set b_size to the total size we want so it will map as
289 * many contiguous blocks as possible at once
290 */
291 memset(&map_bh, 0, sizeof(struct buffer_head));
292 map_bh.b_size = len;
293
294 ret = get_block(inode, start_blk, &map_bh, 0);
295 if (ret)
296 break;
297
298 /* HOLE */
299 if (!buffer_mapped(&map_bh)) {
300 start_blk++;
301
302 /*
303 * We want to handle the case where there is an
304 * allocated block at the front of the file, and then
305 * nothing but holes up to the end of the file properly,
306 * to make sure that extent at the front gets properly
307 * marked with FIEMAP_EXTENT_LAST
308 */
309 if (!past_eof &&
310 blk_to_logical(inode, start_blk) >= isize)
311 past_eof = 1;
312
313 /*
314 * First hole after going past the EOF, this is our
315 * last extent
316 */
317 if (past_eof && size) {
318 flags = FIEMAP_EXTENT_MERGED|FIEMAP_EXTENT_LAST;
319 ret = fiemap_fill_next_extent(fieinfo, logical,
320 phys, size,
321 flags);
322 } else if (size) {
323 ret = fiemap_fill_next_extent(fieinfo, logical,
324 phys, size, flags);
325 size = 0;
326 }
327
328 /* if we have holes up to/past EOF then we're done */
329 if (start_blk > last_blk || past_eof || ret)
330 break;
331 } else {
332 /*
333 * We have gone over the length of what we wanted to
334 * map, and it wasn't the entire file, so add the extent
335 * we got last time and exit.
336 *
337 * This is for the case where say we want to map all the
338 * way up to the second to the last block in a file, but
339 * the last block is a hole, making the second to last
340 * block FIEMAP_EXTENT_LAST. In this case we want to
341 * see if there is a hole after the second to last block
342 * so we can mark it properly. If we found data after
343 * we exceeded the length we were requesting, then we
344 * are good to go, just add the extent to the fieinfo
345 * and break
346 */
347 if (start_blk > last_blk && !whole_file) {
348 ret = fiemap_fill_next_extent(fieinfo, logical,
349 phys, size,
350 flags);
351 break;
352 }
353
354 /*
355 * if size != 0 then we know we already have an extent
356 * to add, so add it.
357 */
358 if (size) {
359 ret = fiemap_fill_next_extent(fieinfo, logical,
360 phys, size,
361 flags);
362 if (ret)
363 break;
364 }
365
366 logical = blk_to_logical(inode, start_blk);
367 phys = blk_to_logical(inode, map_bh.b_blocknr);
368 size = map_bh.b_size;
369 flags = FIEMAP_EXTENT_MERGED;
370
371 start_blk += logical_to_blk(inode, size);
372
373 /*
374 * If we are past the EOF, then we need to make sure as
375 * soon as we find a hole that the last extent we found
376 * is marked with FIEMAP_EXTENT_LAST
377 */
378 if (!past_eof && logical + size >= isize)
379 past_eof = true;
380 }
381 cond_resched();
382 } while (1);
383
384 /* If ret is 1 then we just hit the end of the extent array */
385 if (ret == 1)
386 ret = 0;
387
388 return ret;
389}
390EXPORT_SYMBOL(__generic_block_fiemap);
391
392/**
393 * generic_block_fiemap - FIEMAP for block based inodes
394 * @inode: The inode to map
395 * @fieinfo: The mapping information
396 * @start: The initial block to map
397 * @len: The length of the extect to attempt to map
398 * @get_block: The block mapping function for the fs
399 *
400 * Calls __generic_block_fiemap to map the inode, after taking
401 * the inode's mutex lock.
402 */
403
404int generic_block_fiemap(struct inode *inode,
405 struct fiemap_extent_info *fieinfo, u64 start,
406 u64 len, get_block_t *get_block)
407{
408 int ret;
409 mutex_lock(&inode->i_mutex);
410 ret = __generic_block_fiemap(inode, fieinfo, start, len, get_block);
411 mutex_unlock(&inode->i_mutex);
412 return ret;
413}
414EXPORT_SYMBOL(generic_block_fiemap);
415
416#endif /* CONFIG_BLOCK */
417
418/*
419 * This provides compatibility with legacy XFS pre-allocation ioctls
420 * which predate the fallocate syscall.
421 *
422 * Only the l_start, l_len and l_whence fields of the 'struct space_resv'
423 * are used here, rest are ignored.
424 */
425int ioctl_preallocate(struct file *filp, void __user *argp)
426{
427 struct inode *inode = filp->f_path.dentry->d_inode;
428 struct space_resv sr;
429
430 if (copy_from_user(&sr, argp, sizeof(sr)))
431 return -EFAULT;
432
433 switch (sr.l_whence) {
434 case SEEK_SET:
435 break;
436 case SEEK_CUR:
437 sr.l_start += filp->f_pos;
438 break;
439 case SEEK_END:
440 sr.l_start += i_size_read(inode);
441 break;
442 default:
443 return -EINVAL;
444 }
445
446 return do_fallocate(filp, FALLOC_FL_KEEP_SIZE, sr.l_start, sr.l_len);
447}
448
449static int file_ioctl(struct file *filp, unsigned int cmd,
450 unsigned long arg)
451{
452 struct inode *inode = filp->f_path.dentry->d_inode;
453 int __user *p = (int __user *)arg;
454
455 switch (cmd) {
456 case FIBMAP:
457 return ioctl_fibmap(filp, p);
458 case FIONREAD:
459 return put_user(i_size_read(inode) - filp->f_pos, p);
460 case FS_IOC_RESVSP:
461 case FS_IOC_RESVSP64:
462 return ioctl_preallocate(filp, p);
463 }
464
465 return vfs_ioctl(filp, cmd, arg);
466}
467
468static int ioctl_fionbio(struct file *filp, int __user *argp)
469{
470 unsigned int flag;
471 int on, error;
472
473 error = get_user(on, argp);
474 if (error)
475 return error;
476 flag = O_NONBLOCK;
477#ifdef __sparc__
478 /* SunOS compatibility item. */
479 if (O_NONBLOCK != O_NDELAY)
480 flag |= O_NDELAY;
481#endif
482 spin_lock(&filp->f_lock);
483 if (on)
484 filp->f_flags |= flag;
485 else
486 filp->f_flags &= ~flag;
487 spin_unlock(&filp->f_lock);
488 return error;
489}
490
491static int ioctl_fioasync(unsigned int fd, struct file *filp,
492 int __user *argp)
493{
494 unsigned int flag;
495 int on, error;
496
497 error = get_user(on, argp);
498 if (error)
499 return error;
500 flag = on ? FASYNC : 0;
501
502 /* Did FASYNC state change ? */
503 if ((flag ^ filp->f_flags) & FASYNC) {
504 if (filp->f_op && filp->f_op->fasync)
505 /* fasync() adjusts filp->f_flags */
506 error = filp->f_op->fasync(fd, filp, on);
507 else
508 error = -ENOTTY;
509 }
510 return error < 0 ? error : 0;
511}
512
513static int ioctl_fsfreeze(struct file *filp)
514{
515 struct super_block *sb = filp->f_path.dentry->d_inode->i_sb;
516
517 if (!capable(CAP_SYS_ADMIN))
518 return -EPERM;
519
520 /* If filesystem doesn't support freeze feature, return. */
521 if (sb->s_op->freeze_fs == NULL)
522 return -EOPNOTSUPP;
523
524 /* Freeze */
525 return freeze_super(sb);
526}
527
528static int ioctl_fsthaw(struct file *filp)
529{
530 struct super_block *sb = filp->f_path.dentry->d_inode->i_sb;
531
532 if (!capable(CAP_SYS_ADMIN))
533 return -EPERM;
534
535 /* Thaw */
536 return thaw_super(sb);
537}
538
539/*
540 * When you add any new common ioctls to the switches above and below
541 * please update compat_sys_ioctl() too.
542 *
543 * do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
544 * It's just a simple helper for sys_ioctl and compat_sys_ioctl.
545 */
546int do_vfs_ioctl(struct file *filp, unsigned int fd, unsigned int cmd,
547 unsigned long arg)
548{
549 int error = 0;
550 int __user *argp = (int __user *)arg;
551 struct inode *inode = filp->f_path.dentry->d_inode;
552
553 switch (cmd) {
554 case FIOCLEX:
555 set_close_on_exec(fd, 1);
556 break;
557
558 case FIONCLEX:
559 set_close_on_exec(fd, 0);
560 break;
561
562 case FIONBIO:
563 error = ioctl_fionbio(filp, argp);
564 break;
565
566 case FIOASYNC:
567 error = ioctl_fioasync(fd, filp, argp);
568 break;
569
570 case FIOQSIZE:
571 if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
572 S_ISLNK(inode->i_mode)) {
573 loff_t res = inode_get_bytes(inode);
574 error = copy_to_user(argp, &res, sizeof(res)) ?
575 -EFAULT : 0;
576 } else
577 error = -ENOTTY;
578 break;
579
580 case FIFREEZE:
581 error = ioctl_fsfreeze(filp);
582 break;
583
584 case FITHAW:
585 error = ioctl_fsthaw(filp);
586 break;
587
588 case FS_IOC_FIEMAP:
589 return ioctl_fiemap(filp, arg);
590
591 case FIGETBSZ:
592 return put_user(inode->i_sb->s_blocksize, argp);
593
594 default:
595 if (S_ISREG(inode->i_mode))
596 error = file_ioctl(filp, cmd, arg);
597 else
598 error = vfs_ioctl(filp, cmd, arg);
599 break;
600 }
601 return error;
602}
603
604SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
605{
606 struct file *filp;
607 int error = -EBADF;
608 int fput_needed;
609
610 filp = fget_light(fd, &fput_needed);
611 if (!filp)
612 goto out;
613
614 error = security_file_ioctl(filp, cmd, arg);
615 if (error)
616 goto out_fput;
617
618 error = do_vfs_ioctl(filp, fd, cmd, arg);
619 out_fput:
620 fput_light(filp, fput_needed);
621 out:
622 return error;
623}