Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / fs / btrfs / ioctl.c
1 /*
2  * Copyright (C) 2007 Oracle.  All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public
6  * License v2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
11  * General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public
14  * License along with this program; if not, write to the
15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16  * Boston, MA 021110-1307, USA.
17  */
18
19 #include <linux/kernel.h>
20 #include <linux/bio.h>
21 #include <linux/buffer_head.h>
22 #include <linux/file.h>
23 #include <linux/fs.h>
24 #include <linux/fsnotify.h>
25 #include <linux/pagemap.h>
26 #include <linux/highmem.h>
27 #include <linux/time.h>
28 #include <linux/init.h>
29 #include <linux/string.h>
30 #include <linux/backing-dev.h>
31 #include <linux/mount.h>
32 #include <linux/mpage.h>
33 #include <linux/namei.h>
34 #include <linux/swap.h>
35 #include <linux/writeback.h>
36 #include <linux/statfs.h>
37 #include <linux/compat.h>
38 #include <linux/bit_spinlock.h>
39 #include <linux/security.h>
40 #include <linux/xattr.h>
41 #include <linux/vmalloc.h>
42 #include <linux/slab.h>
43 #include "compat.h"
44 #include "ctree.h"
45 #include "disk-io.h"
46 #include "transaction.h"
47 #include "btrfs_inode.h"
48 #include "ioctl.h"
49 #include "print-tree.h"
50 #include "volumes.h"
51 #include "locking.h"
52
53 /* Mask out flags that are inappropriate for the given type of inode. */
54 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
55 {
56         if (S_ISDIR(mode))
57                 return flags;
58         else if (S_ISREG(mode))
59                 return flags & ~FS_DIRSYNC_FL;
60         else
61                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
62 }
63
64 /*
65  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
66  */
67 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
68 {
69         unsigned int iflags = 0;
70
71         if (flags & BTRFS_INODE_SYNC)
72                 iflags |= FS_SYNC_FL;
73         if (flags & BTRFS_INODE_IMMUTABLE)
74                 iflags |= FS_IMMUTABLE_FL;
75         if (flags & BTRFS_INODE_APPEND)
76                 iflags |= FS_APPEND_FL;
77         if (flags & BTRFS_INODE_NODUMP)
78                 iflags |= FS_NODUMP_FL;
79         if (flags & BTRFS_INODE_NOATIME)
80                 iflags |= FS_NOATIME_FL;
81         if (flags & BTRFS_INODE_DIRSYNC)
82                 iflags |= FS_DIRSYNC_FL;
83
84         return iflags;
85 }
86
87 /*
88  * Update inode->i_flags based on the btrfs internal flags.
89  */
90 void btrfs_update_iflags(struct inode *inode)
91 {
92         struct btrfs_inode *ip = BTRFS_I(inode);
93
94         inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
95
96         if (ip->flags & BTRFS_INODE_SYNC)
97                 inode->i_flags |= S_SYNC;
98         if (ip->flags & BTRFS_INODE_IMMUTABLE)
99                 inode->i_flags |= S_IMMUTABLE;
100         if (ip->flags & BTRFS_INODE_APPEND)
101                 inode->i_flags |= S_APPEND;
102         if (ip->flags & BTRFS_INODE_NOATIME)
103                 inode->i_flags |= S_NOATIME;
104         if (ip->flags & BTRFS_INODE_DIRSYNC)
105                 inode->i_flags |= S_DIRSYNC;
106 }
107
108 /*
109  * Inherit flags from the parent inode.
110  *
111  * Unlike extN we don't have any flags we don't want to inherit currently.
112  */
113 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
114 {
115         unsigned int flags;
116
117         if (!dir)
118                 return;
119
120         flags = BTRFS_I(dir)->flags;
121
122         if (S_ISREG(inode->i_mode))
123                 flags &= ~BTRFS_INODE_DIRSYNC;
124         else if (!S_ISDIR(inode->i_mode))
125                 flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);
126
127         BTRFS_I(inode)->flags = flags;
128         btrfs_update_iflags(inode);
129 }
130
131 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
132 {
133         struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
134         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
135
136         if (copy_to_user(arg, &flags, sizeof(flags)))
137                 return -EFAULT;
138         return 0;
139 }
140
141 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
142 {
143         struct inode *inode = file->f_path.dentry->d_inode;
144         struct btrfs_inode *ip = BTRFS_I(inode);
145         struct btrfs_root *root = ip->root;
146         struct btrfs_trans_handle *trans;
147         unsigned int flags, oldflags;
148         int ret;
149
150         if (copy_from_user(&flags, arg, sizeof(flags)))
151                 return -EFAULT;
152
153         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
154                       FS_NOATIME_FL | FS_NODUMP_FL | \
155                       FS_SYNC_FL | FS_DIRSYNC_FL))
156                 return -EOPNOTSUPP;
157
158         if (!is_owner_or_cap(inode))
159                 return -EACCES;
160
161         mutex_lock(&inode->i_mutex);
162
163         flags = btrfs_mask_flags(inode->i_mode, flags);
164         oldflags = btrfs_flags_to_ioctl(ip->flags);
165         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
166                 if (!capable(CAP_LINUX_IMMUTABLE)) {
167                         ret = -EPERM;
168                         goto out_unlock;
169                 }
170         }
171
172         ret = mnt_want_write(file->f_path.mnt);
173         if (ret)
174                 goto out_unlock;
175
176         if (flags & FS_SYNC_FL)
177                 ip->flags |= BTRFS_INODE_SYNC;
178         else
179                 ip->flags &= ~BTRFS_INODE_SYNC;
180         if (flags & FS_IMMUTABLE_FL)
181                 ip->flags |= BTRFS_INODE_IMMUTABLE;
182         else
183                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
184         if (flags & FS_APPEND_FL)
185                 ip->flags |= BTRFS_INODE_APPEND;
186         else
187                 ip->flags &= ~BTRFS_INODE_APPEND;
188         if (flags & FS_NODUMP_FL)
189                 ip->flags |= BTRFS_INODE_NODUMP;
190         else
191                 ip->flags &= ~BTRFS_INODE_NODUMP;
192         if (flags & FS_NOATIME_FL)
193                 ip->flags |= BTRFS_INODE_NOATIME;
194         else
195                 ip->flags &= ~BTRFS_INODE_NOATIME;
196         if (flags & FS_DIRSYNC_FL)
197                 ip->flags |= BTRFS_INODE_DIRSYNC;
198         else
199                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
200
201
202         trans = btrfs_join_transaction(root, 1);
203         BUG_ON(!trans);
204
205         ret = btrfs_update_inode(trans, root, inode);
206         BUG_ON(ret);
207
208         btrfs_update_iflags(inode);
209         inode->i_ctime = CURRENT_TIME;
210         btrfs_end_transaction(trans, root);
211
212         mnt_drop_write(file->f_path.mnt);
213  out_unlock:
214         mutex_unlock(&inode->i_mutex);
215         return 0;
216 }
217
218 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
219 {
220         struct inode *inode = file->f_path.dentry->d_inode;
221
222         return put_user(inode->i_generation, arg);
223 }
224
225 static noinline int create_subvol(struct btrfs_root *root,
226                                   struct dentry *dentry,
227                                   char *name, int namelen)
228 {
229         struct btrfs_trans_handle *trans;
230         struct btrfs_key key;
231         struct btrfs_root_item root_item;
232         struct btrfs_inode_item *inode_item;
233         struct extent_buffer *leaf;
234         struct btrfs_root *new_root;
235         struct inode *dir = dentry->d_parent->d_inode;
236         int ret;
237         int err;
238         u64 objectid;
239         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
240         u64 index = 0;
241
242         ret = btrfs_find_free_objectid(NULL, root->fs_info->tree_root,
243                                        0, &objectid);
244         if (ret)
245                 return ret;
246         /*
247          * 1 - inode item
248          * 2 - refs
249          * 1 - root item
250          * 2 - dir items
251          */
252         trans = btrfs_start_transaction(root, 6);
253         if (IS_ERR(trans))
254                 return PTR_ERR(trans);
255
256         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
257                                       0, objectid, NULL, 0, 0, 0);
258         if (IS_ERR(leaf)) {
259                 ret = PTR_ERR(leaf);
260                 goto fail;
261         }
262
263         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
264         btrfs_set_header_bytenr(leaf, leaf->start);
265         btrfs_set_header_generation(leaf, trans->transid);
266         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
267         btrfs_set_header_owner(leaf, objectid);
268
269         write_extent_buffer(leaf, root->fs_info->fsid,
270                             (unsigned long)btrfs_header_fsid(leaf),
271                             BTRFS_FSID_SIZE);
272         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
273                             (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
274                             BTRFS_UUID_SIZE);
275         btrfs_mark_buffer_dirty(leaf);
276
277         inode_item = &root_item.inode;
278         memset(inode_item, 0, sizeof(*inode_item));
279         inode_item->generation = cpu_to_le64(1);
280         inode_item->size = cpu_to_le64(3);
281         inode_item->nlink = cpu_to_le32(1);
282         inode_item->nbytes = cpu_to_le64(root->leafsize);
283         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
284
285         btrfs_set_root_bytenr(&root_item, leaf->start);
286         btrfs_set_root_generation(&root_item, trans->transid);
287         btrfs_set_root_level(&root_item, 0);
288         btrfs_set_root_refs(&root_item, 1);
289         btrfs_set_root_used(&root_item, leaf->len);
290         btrfs_set_root_last_snapshot(&root_item, 0);
291
292         memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
293         root_item.drop_level = 0;
294
295         btrfs_tree_unlock(leaf);
296         free_extent_buffer(leaf);
297         leaf = NULL;
298
299         btrfs_set_root_dirid(&root_item, new_dirid);
300
301         key.objectid = objectid;
302         key.offset = 0;
303         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
304         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
305                                 &root_item);
306         if (ret)
307                 goto fail;
308
309         key.offset = (u64)-1;
310         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
311         BUG_ON(IS_ERR(new_root));
312
313         btrfs_record_root_in_trans(trans, new_root);
314
315         ret = btrfs_create_subvol_root(trans, new_root, new_dirid,
316                                        BTRFS_I(dir)->block_group);
317         /*
318          * insert the directory item
319          */
320         ret = btrfs_set_inode_index(dir, &index);
321         BUG_ON(ret);
322
323         ret = btrfs_insert_dir_item(trans, root,
324                                     name, namelen, dir->i_ino, &key,
325                                     BTRFS_FT_DIR, index);
326         if (ret)
327                 goto fail;
328
329         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
330         ret = btrfs_update_inode(trans, root, dir);
331         BUG_ON(ret);
332
333         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
334                                  objectid, root->root_key.objectid,
335                                  dir->i_ino, index, name, namelen);
336
337         BUG_ON(ret);
338
339         d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
340 fail:
341         err = btrfs_commit_transaction(trans, root);
342         if (err && !ret)
343                 ret = err;
344         return ret;
345 }
346
347 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry)
348 {
349         struct inode *inode;
350         struct btrfs_pending_snapshot *pending_snapshot;
351         struct btrfs_trans_handle *trans;
352         int ret;
353
354         if (!root->ref_cows)
355                 return -EINVAL;
356
357         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
358         if (!pending_snapshot)
359                 return -ENOMEM;
360
361         btrfs_init_block_rsv(&pending_snapshot->block_rsv);
362         pending_snapshot->dentry = dentry;
363         pending_snapshot->root = root;
364
365         trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
366         if (IS_ERR(trans)) {
367                 ret = PTR_ERR(trans);
368                 goto fail;
369         }
370
371         ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
372         BUG_ON(ret);
373
374         list_add(&pending_snapshot->list,
375                  &trans->transaction->pending_snapshots);
376         ret = btrfs_commit_transaction(trans, root->fs_info->extent_root);
377         BUG_ON(ret);
378
379         ret = pending_snapshot->error;
380         if (ret)
381                 goto fail;
382
383         btrfs_orphan_cleanup(pending_snapshot->snap);
384
385         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
386         if (IS_ERR(inode)) {
387                 ret = PTR_ERR(inode);
388                 goto fail;
389         }
390         BUG_ON(!inode);
391         d_instantiate(dentry, inode);
392         ret = 0;
393 fail:
394         kfree(pending_snapshot);
395         return ret;
396 }
397
398 /* copy of may_create in fs/namei.c() */
399 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
400 {
401         if (child->d_inode)
402                 return -EEXIST;
403         if (IS_DEADDIR(dir))
404                 return -ENOENT;
405         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
406 }
407
408 /*
409  * Create a new subvolume below @parent.  This is largely modeled after
410  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
411  * inside this filesystem so it's quite a bit simpler.
412  */
413 static noinline int btrfs_mksubvol(struct path *parent,
414                                    char *name, int namelen,
415                                    struct btrfs_root *snap_src)
416 {
417         struct inode *dir  = parent->dentry->d_inode;
418         struct dentry *dentry;
419         int error;
420
421         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
422
423         dentry = lookup_one_len(name, parent->dentry, namelen);
424         error = PTR_ERR(dentry);
425         if (IS_ERR(dentry))
426                 goto out_unlock;
427
428         error = -EEXIST;
429         if (dentry->d_inode)
430                 goto out_dput;
431
432         error = mnt_want_write(parent->mnt);
433         if (error)
434                 goto out_dput;
435
436         error = btrfs_may_create(dir, dentry);
437         if (error)
438                 goto out_drop_write;
439
440         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
441
442         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
443                 goto out_up_read;
444
445         if (snap_src) {
446                 error = create_snapshot(snap_src, dentry);
447         } else {
448                 error = create_subvol(BTRFS_I(dir)->root, dentry,
449                                       name, namelen);
450         }
451         if (!error)
452                 fsnotify_mkdir(dir, dentry);
453 out_up_read:
454         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
455 out_drop_write:
456         mnt_drop_write(parent->mnt);
457 out_dput:
458         dput(dentry);
459 out_unlock:
460         mutex_unlock(&dir->i_mutex);
461         return error;
462 }
463
464 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
465                                int thresh, u64 *last_len, u64 *skip,
466                                u64 *defrag_end)
467 {
468         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
469         struct extent_map *em = NULL;
470         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
471         int ret = 1;
472
473
474         if (thresh == 0)
475                 thresh = 256 * 1024;
476
477         /*
478          * make sure that once we start defragging and extent, we keep on
479          * defragging it
480          */
481         if (start < *defrag_end)
482                 return 1;
483
484         *skip = 0;
485
486         /*
487          * hopefully we have this extent in the tree already, try without
488          * the full extent lock
489          */
490         read_lock(&em_tree->lock);
491         em = lookup_extent_mapping(em_tree, start, len);
492         read_unlock(&em_tree->lock);
493
494         if (!em) {
495                 /* get the big lock and read metadata off disk */
496                 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
497                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
498                 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
499
500                 if (IS_ERR(em))
501                         return 0;
502         }
503
504         /* this will cover holes, and inline extents */
505         if (em->block_start >= EXTENT_MAP_LAST_BYTE)
506                 ret = 0;
507
508         /*
509          * we hit a real extent, if it is big don't bother defragging it again
510          */
511         if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
512                 ret = 0;
513
514         /*
515          * last_len ends up being a counter of how many bytes we've defragged.
516          * every time we choose not to defrag an extent, we reset *last_len
517          * so that the next tiny extent will force a defrag.
518          *
519          * The end result of this is that tiny extents before a single big
520          * extent will force at least part of that big extent to be defragged.
521          */
522         if (ret) {
523                 *last_len += len;
524                 *defrag_end = extent_map_end(em);
525         } else {
526                 *last_len = 0;
527                 *skip = extent_map_end(em);
528                 *defrag_end = 0;
529         }
530
531         free_extent_map(em);
532         return ret;
533 }
534
535 static int btrfs_defrag_file(struct file *file,
536                              struct btrfs_ioctl_defrag_range_args *range)
537 {
538         struct inode *inode = fdentry(file)->d_inode;
539         struct btrfs_root *root = BTRFS_I(inode)->root;
540         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
541         struct btrfs_ordered_extent *ordered;
542         struct page *page;
543         unsigned long last_index;
544         unsigned long ra_pages = root->fs_info->bdi.ra_pages;
545         unsigned long total_read = 0;
546         u64 page_start;
547         u64 page_end;
548         u64 last_len = 0;
549         u64 skip = 0;
550         u64 defrag_end = 0;
551         unsigned long i;
552         int ret;
553
554         if (inode->i_size == 0)
555                 return 0;
556
557         if (range->start + range->len > range->start) {
558                 last_index = min_t(u64, inode->i_size - 1,
559                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
560         } else {
561                 last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
562         }
563
564         i = range->start >> PAGE_CACHE_SHIFT;
565         while (i <= last_index) {
566                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
567                                         PAGE_CACHE_SIZE,
568                                         range->extent_thresh,
569                                         &last_len, &skip,
570                                         &defrag_end)) {
571                         unsigned long next;
572                         /*
573                          * the should_defrag function tells us how much to skip
574                          * bump our counter by the suggested amount
575                          */
576                         next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
577                         i = max(i + 1, next);
578                         continue;
579                 }
580
581                 if (total_read % ra_pages == 0) {
582                         btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i,
583                                        min(last_index, i + ra_pages - 1));
584                 }
585                 total_read++;
586                 mutex_lock(&inode->i_mutex);
587                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
588                         BTRFS_I(inode)->force_compress = 1;
589
590                 ret  = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
591                 if (ret)
592                         goto err_unlock;
593 again:
594                 if (inode->i_size == 0 ||
595                     i > ((inode->i_size - 1) >> PAGE_CACHE_SHIFT)) {
596                         ret = 0;
597                         goto err_reservations;
598                 }
599
600                 page = grab_cache_page(inode->i_mapping, i);
601                 if (!page) {
602                         ret = -ENOMEM;
603                         goto err_reservations;
604                 }
605
606                 if (!PageUptodate(page)) {
607                         btrfs_readpage(NULL, page);
608                         lock_page(page);
609                         if (!PageUptodate(page)) {
610                                 unlock_page(page);
611                                 page_cache_release(page);
612                                 ret = -EIO;
613                                 goto err_reservations;
614                         }
615                 }
616
617                 if (page->mapping != inode->i_mapping) {
618                         unlock_page(page);
619                         page_cache_release(page);
620                         goto again;
621                 }
622
623                 wait_on_page_writeback(page);
624
625                 if (PageDirty(page)) {
626                         btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
627                         goto loop_unlock;
628                 }
629
630                 page_start = (u64)page->index << PAGE_CACHE_SHIFT;
631                 page_end = page_start + PAGE_CACHE_SIZE - 1;
632                 lock_extent(io_tree, page_start, page_end, GFP_NOFS);
633
634                 ordered = btrfs_lookup_ordered_extent(inode, page_start);
635                 if (ordered) {
636                         unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
637                         unlock_page(page);
638                         page_cache_release(page);
639                         btrfs_start_ordered_extent(inode, ordered, 1);
640                         btrfs_put_ordered_extent(ordered);
641                         goto again;
642                 }
643                 set_page_extent_mapped(page);
644
645                 /*
646                  * this makes sure page_mkwrite is called on the
647                  * page if it is dirtied again later
648                  */
649                 clear_page_dirty_for_io(page);
650                 clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start,
651                                   page_end, EXTENT_DIRTY | EXTENT_DELALLOC |
652                                   EXTENT_DO_ACCOUNTING, GFP_NOFS);
653
654                 btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
655                 ClearPageChecked(page);
656                 set_page_dirty(page);
657                 unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
658
659 loop_unlock:
660                 unlock_page(page);
661                 page_cache_release(page);
662                 mutex_unlock(&inode->i_mutex);
663
664                 balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
665                 i++;
666         }
667
668         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
669                 filemap_flush(inode->i_mapping);
670
671         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
672                 /* the filemap_flush will queue IO into the worker threads, but
673                  * we have to make sure the IO is actually started and that
674                  * ordered extents get created before we return
675                  */
676                 atomic_inc(&root->fs_info->async_submit_draining);
677                 while (atomic_read(&root->fs_info->nr_async_submits) ||
678                       atomic_read(&root->fs_info->async_delalloc_pages)) {
679                         wait_event(root->fs_info->async_submit_wait,
680                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
681                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
682                 }
683                 atomic_dec(&root->fs_info->async_submit_draining);
684
685                 mutex_lock(&inode->i_mutex);
686                 BTRFS_I(inode)->force_compress = 0;
687                 mutex_unlock(&inode->i_mutex);
688         }
689
690         return 0;
691
692 err_reservations:
693         btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
694 err_unlock:
695         mutex_unlock(&inode->i_mutex);
696         return ret;
697 }
698
699 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
700                                         void __user *arg)
701 {
702         u64 new_size;
703         u64 old_size;
704         u64 devid = 1;
705         struct btrfs_ioctl_vol_args *vol_args;
706         struct btrfs_trans_handle *trans;
707         struct btrfs_device *device = NULL;
708         char *sizestr;
709         char *devstr = NULL;
710         int ret = 0;
711         int namelen;
712         int mod = 0;
713
714         if (root->fs_info->sb->s_flags & MS_RDONLY)
715                 return -EROFS;
716
717         if (!capable(CAP_SYS_ADMIN))
718                 return -EPERM;
719
720         vol_args = memdup_user(arg, sizeof(*vol_args));
721         if (IS_ERR(vol_args))
722                 return PTR_ERR(vol_args);
723
724         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
725         namelen = strlen(vol_args->name);
726
727         mutex_lock(&root->fs_info->volume_mutex);
728         sizestr = vol_args->name;
729         devstr = strchr(sizestr, ':');
730         if (devstr) {
731                 char *end;
732                 sizestr = devstr + 1;
733                 *devstr = '\0';
734                 devstr = vol_args->name;
735                 devid = simple_strtoull(devstr, &end, 10);
736                 printk(KERN_INFO "resizing devid %llu\n",
737                        (unsigned long long)devid);
738         }
739         device = btrfs_find_device(root, devid, NULL, NULL);
740         if (!device) {
741                 printk(KERN_INFO "resizer unable to find device %llu\n",
742                        (unsigned long long)devid);
743                 ret = -EINVAL;
744                 goto out_unlock;
745         }
746         if (!strcmp(sizestr, "max"))
747                 new_size = device->bdev->bd_inode->i_size;
748         else {
749                 if (sizestr[0] == '-') {
750                         mod = -1;
751                         sizestr++;
752                 } else if (sizestr[0] == '+') {
753                         mod = 1;
754                         sizestr++;
755                 }
756                 new_size = memparse(sizestr, NULL);
757                 if (new_size == 0) {
758                         ret = -EINVAL;
759                         goto out_unlock;
760                 }
761         }
762
763         old_size = device->total_bytes;
764
765         if (mod < 0) {
766                 if (new_size > old_size) {
767                         ret = -EINVAL;
768                         goto out_unlock;
769                 }
770                 new_size = old_size - new_size;
771         } else if (mod > 0) {
772                 new_size = old_size + new_size;
773         }
774
775         if (new_size < 256 * 1024 * 1024) {
776                 ret = -EINVAL;
777                 goto out_unlock;
778         }
779         if (new_size > device->bdev->bd_inode->i_size) {
780                 ret = -EFBIG;
781                 goto out_unlock;
782         }
783
784         do_div(new_size, root->sectorsize);
785         new_size *= root->sectorsize;
786
787         printk(KERN_INFO "new size for %s is %llu\n",
788                 device->name, (unsigned long long)new_size);
789
790         if (new_size > old_size) {
791                 trans = btrfs_start_transaction(root, 0);
792                 ret = btrfs_grow_device(trans, device, new_size);
793                 btrfs_commit_transaction(trans, root);
794         } else {
795                 ret = btrfs_shrink_device(device, new_size);
796         }
797
798 out_unlock:
799         mutex_unlock(&root->fs_info->volume_mutex);
800         kfree(vol_args);
801         return ret;
802 }
803
804 static noinline int btrfs_ioctl_snap_create(struct file *file,
805                                             void __user *arg, int subvol)
806 {
807         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
808         struct btrfs_ioctl_vol_args *vol_args;
809         struct file *src_file;
810         int namelen;
811         int ret = 0;
812
813         if (root->fs_info->sb->s_flags & MS_RDONLY)
814                 return -EROFS;
815
816         vol_args = memdup_user(arg, sizeof(*vol_args));
817         if (IS_ERR(vol_args))
818                 return PTR_ERR(vol_args);
819
820         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
821         namelen = strlen(vol_args->name);
822         if (strchr(vol_args->name, '/')) {
823                 ret = -EINVAL;
824                 goto out;
825         }
826
827         if (subvol) {
828                 ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
829                                      NULL);
830         } else {
831                 struct inode *src_inode;
832                 src_file = fget(vol_args->fd);
833                 if (!src_file) {
834                         ret = -EINVAL;
835                         goto out;
836                 }
837
838                 src_inode = src_file->f_path.dentry->d_inode;
839                 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
840                         printk(KERN_INFO "btrfs: Snapshot src from "
841                                "another FS\n");
842                         ret = -EINVAL;
843                         fput(src_file);
844                         goto out;
845                 }
846                 ret = btrfs_mksubvol(&file->f_path, vol_args->name, namelen,
847                                      BTRFS_I(src_inode)->root);
848                 fput(src_file);
849         }
850 out:
851         kfree(vol_args);
852         return ret;
853 }
854
855 /*
856  * helper to check if the subvolume references other subvolumes
857  */
858 static noinline int may_destroy_subvol(struct btrfs_root *root)
859 {
860         struct btrfs_path *path;
861         struct btrfs_key key;
862         int ret;
863
864         path = btrfs_alloc_path();
865         if (!path)
866                 return -ENOMEM;
867
868         key.objectid = root->root_key.objectid;
869         key.type = BTRFS_ROOT_REF_KEY;
870         key.offset = (u64)-1;
871
872         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
873                                 &key, path, 0, 0);
874         if (ret < 0)
875                 goto out;
876         BUG_ON(ret == 0);
877
878         ret = 0;
879         if (path->slots[0] > 0) {
880                 path->slots[0]--;
881                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
882                 if (key.objectid == root->root_key.objectid &&
883                     key.type == BTRFS_ROOT_REF_KEY)
884                         ret = -ENOTEMPTY;
885         }
886 out:
887         btrfs_free_path(path);
888         return ret;
889 }
890
891 static noinline int key_in_sk(struct btrfs_key *key,
892                               struct btrfs_ioctl_search_key *sk)
893 {
894         struct btrfs_key test;
895         int ret;
896
897         test.objectid = sk->min_objectid;
898         test.type = sk->min_type;
899         test.offset = sk->min_offset;
900
901         ret = btrfs_comp_cpu_keys(key, &test);
902         if (ret < 0)
903                 return 0;
904
905         test.objectid = sk->max_objectid;
906         test.type = sk->max_type;
907         test.offset = sk->max_offset;
908
909         ret = btrfs_comp_cpu_keys(key, &test);
910         if (ret > 0)
911                 return 0;
912         return 1;
913 }
914
915 static noinline int copy_to_sk(struct btrfs_root *root,
916                                struct btrfs_path *path,
917                                struct btrfs_key *key,
918                                struct btrfs_ioctl_search_key *sk,
919                                char *buf,
920                                unsigned long *sk_offset,
921                                int *num_found)
922 {
923         u64 found_transid;
924         struct extent_buffer *leaf;
925         struct btrfs_ioctl_search_header sh;
926         unsigned long item_off;
927         unsigned long item_len;
928         int nritems;
929         int i;
930         int slot;
931         int found = 0;
932         int ret = 0;
933
934         leaf = path->nodes[0];
935         slot = path->slots[0];
936         nritems = btrfs_header_nritems(leaf);
937
938         if (btrfs_header_generation(leaf) > sk->max_transid) {
939                 i = nritems;
940                 goto advance_key;
941         }
942         found_transid = btrfs_header_generation(leaf);
943
944         for (i = slot; i < nritems; i++) {
945                 item_off = btrfs_item_ptr_offset(leaf, i);
946                 item_len = btrfs_item_size_nr(leaf, i);
947
948                 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
949                         item_len = 0;
950
951                 if (sizeof(sh) + item_len + *sk_offset >
952                     BTRFS_SEARCH_ARGS_BUFSIZE) {
953                         ret = 1;
954                         goto overflow;
955                 }
956
957                 btrfs_item_key_to_cpu(leaf, key, i);
958                 if (!key_in_sk(key, sk))
959                         continue;
960
961                 sh.objectid = key->objectid;
962                 sh.offset = key->offset;
963                 sh.type = key->type;
964                 sh.len = item_len;
965                 sh.transid = found_transid;
966
967                 /* copy search result header */
968                 memcpy(buf + *sk_offset, &sh, sizeof(sh));
969                 *sk_offset += sizeof(sh);
970
971                 if (item_len) {
972                         char *p = buf + *sk_offset;
973                         /* copy the item */
974                         read_extent_buffer(leaf, p,
975                                            item_off, item_len);
976                         *sk_offset += item_len;
977                 }
978                 found++;
979
980                 if (*num_found >= sk->nr_items)
981                         break;
982         }
983 advance_key:
984         ret = 0;
985         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
986                 key->offset++;
987         else if (key->type < (u8)-1 && key->type < sk->max_type) {
988                 key->offset = 0;
989                 key->type++;
990         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
991                 key->offset = 0;
992                 key->type = 0;
993                 key->objectid++;
994         } else
995                 ret = 1;
996 overflow:
997         *num_found += found;
998         return ret;
999 }
1000
1001 static noinline int search_ioctl(struct inode *inode,
1002                                  struct btrfs_ioctl_search_args *args)
1003 {
1004         struct btrfs_root *root;
1005         struct btrfs_key key;
1006         struct btrfs_key max_key;
1007         struct btrfs_path *path;
1008         struct btrfs_ioctl_search_key *sk = &args->key;
1009         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1010         int ret;
1011         int num_found = 0;
1012         unsigned long sk_offset = 0;
1013
1014         path = btrfs_alloc_path();
1015         if (!path)
1016                 return -ENOMEM;
1017
1018         if (sk->tree_id == 0) {
1019                 /* search the root of the inode that was passed */
1020                 root = BTRFS_I(inode)->root;
1021         } else {
1022                 key.objectid = sk->tree_id;
1023                 key.type = BTRFS_ROOT_ITEM_KEY;
1024                 key.offset = (u64)-1;
1025                 root = btrfs_read_fs_root_no_name(info, &key);
1026                 if (IS_ERR(root)) {
1027                         printk(KERN_ERR "could not find root %llu\n",
1028                                sk->tree_id);
1029                         btrfs_free_path(path);
1030                         return -ENOENT;
1031                 }
1032         }
1033
1034         key.objectid = sk->min_objectid;
1035         key.type = sk->min_type;
1036         key.offset = sk->min_offset;
1037
1038         max_key.objectid = sk->max_objectid;
1039         max_key.type = sk->max_type;
1040         max_key.offset = sk->max_offset;
1041
1042         path->keep_locks = 1;
1043
1044         while(1) {
1045                 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1046                                            sk->min_transid);
1047                 if (ret != 0) {
1048                         if (ret > 0)
1049                                 ret = 0;
1050                         goto err;
1051                 }
1052                 ret = copy_to_sk(root, path, &key, sk, args->buf,
1053                                  &sk_offset, &num_found);
1054                 btrfs_release_path(root, path);
1055                 if (ret || num_found >= sk->nr_items)
1056                         break;
1057
1058         }
1059         ret = 0;
1060 err:
1061         sk->nr_items = num_found;
1062         btrfs_free_path(path);
1063         return ret;
1064 }
1065
1066 static noinline int btrfs_ioctl_tree_search(struct file *file,
1067                                            void __user *argp)
1068 {
1069          struct btrfs_ioctl_search_args *args;
1070          struct inode *inode;
1071          int ret;
1072
1073         if (!capable(CAP_SYS_ADMIN))
1074                 return -EPERM;
1075
1076         args = kmalloc(sizeof(*args), GFP_KERNEL);
1077         if (!args)
1078                 return -ENOMEM;
1079
1080         if (copy_from_user(args, argp, sizeof(*args))) {
1081                 kfree(args);
1082                 return -EFAULT;
1083         }
1084         inode = fdentry(file)->d_inode;
1085         ret = search_ioctl(inode, args);
1086         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1087                 ret = -EFAULT;
1088         kfree(args);
1089         return ret;
1090 }
1091
1092 /*
1093  * Search INODE_REFs to identify path name of 'dirid' directory
1094  * in a 'tree_id' tree. and sets path name to 'name'.
1095  */
1096 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1097                                 u64 tree_id, u64 dirid, char *name)
1098 {
1099         struct btrfs_root *root;
1100         struct btrfs_key key;
1101         char *ptr;
1102         int ret = -1;
1103         int slot;
1104         int len;
1105         int total_len = 0;
1106         struct btrfs_inode_ref *iref;
1107         struct extent_buffer *l;
1108         struct btrfs_path *path;
1109
1110         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1111                 name[0]='\0';
1112                 return 0;
1113         }
1114
1115         path = btrfs_alloc_path();
1116         if (!path)
1117                 return -ENOMEM;
1118
1119         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1120
1121         key.objectid = tree_id;
1122         key.type = BTRFS_ROOT_ITEM_KEY;
1123         key.offset = (u64)-1;
1124         root = btrfs_read_fs_root_no_name(info, &key);
1125         if (IS_ERR(root)) {
1126                 printk(KERN_ERR "could not find root %llu\n", tree_id);
1127                 ret = -ENOENT;
1128                 goto out;
1129         }
1130
1131         key.objectid = dirid;
1132         key.type = BTRFS_INODE_REF_KEY;
1133         key.offset = (u64)-1;
1134
1135         while(1) {
1136                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1137                 if (ret < 0)
1138                         goto out;
1139
1140                 l = path->nodes[0];
1141                 slot = path->slots[0];
1142                 if (ret > 0 && slot > 0)
1143                         slot--;
1144                 btrfs_item_key_to_cpu(l, &key, slot);
1145
1146                 if (ret > 0 && (key.objectid != dirid ||
1147                                 key.type != BTRFS_INODE_REF_KEY)) {
1148                         ret = -ENOENT;
1149                         goto out;
1150                 }
1151
1152                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1153                 len = btrfs_inode_ref_name_len(l, iref);
1154                 ptr -= len + 1;
1155                 total_len += len + 1;
1156                 if (ptr < name)
1157                         goto out;
1158
1159                 *(ptr + len) = '/';
1160                 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1161
1162                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1163                         break;
1164
1165                 btrfs_release_path(root, path);
1166                 key.objectid = key.offset;
1167                 key.offset = (u64)-1;
1168                 dirid = key.objectid;
1169
1170         }
1171         if (ptr < name)
1172                 goto out;
1173         memcpy(name, ptr, total_len);
1174         name[total_len]='\0';
1175         ret = 0;
1176 out:
1177         btrfs_free_path(path);
1178         return ret;
1179 }
1180
1181 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1182                                            void __user *argp)
1183 {
1184          struct btrfs_ioctl_ino_lookup_args *args;
1185          struct inode *inode;
1186          int ret;
1187
1188         if (!capable(CAP_SYS_ADMIN))
1189                 return -EPERM;
1190
1191         args = kmalloc(sizeof(*args), GFP_KERNEL);
1192         if (!args)
1193                 return -ENOMEM;
1194
1195         if (copy_from_user(args, argp, sizeof(*args))) {
1196                 kfree(args);
1197                 return -EFAULT;
1198         }
1199         inode = fdentry(file)->d_inode;
1200
1201         if (args->treeid == 0)
1202                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1203
1204         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1205                                         args->treeid, args->objectid,
1206                                         args->name);
1207
1208         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1209                 ret = -EFAULT;
1210
1211         kfree(args);
1212         return ret;
1213 }
1214
1215 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1216                                              void __user *arg)
1217 {
1218         struct dentry *parent = fdentry(file);
1219         struct dentry *dentry;
1220         struct inode *dir = parent->d_inode;
1221         struct inode *inode;
1222         struct btrfs_root *root = BTRFS_I(dir)->root;
1223         struct btrfs_root *dest = NULL;
1224         struct btrfs_ioctl_vol_args *vol_args;
1225         struct btrfs_trans_handle *trans;
1226         int namelen;
1227         int ret;
1228         int err = 0;
1229
1230         if (!capable(CAP_SYS_ADMIN))
1231                 return -EPERM;
1232
1233         vol_args = memdup_user(arg, sizeof(*vol_args));
1234         if (IS_ERR(vol_args))
1235                 return PTR_ERR(vol_args);
1236
1237         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1238         namelen = strlen(vol_args->name);
1239         if (strchr(vol_args->name, '/') ||
1240             strncmp(vol_args->name, "..", namelen) == 0) {
1241                 err = -EINVAL;
1242                 goto out;
1243         }
1244
1245         err = mnt_want_write(file->f_path.mnt);
1246         if (err)
1247                 goto out;
1248
1249         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1250         dentry = lookup_one_len(vol_args->name, parent, namelen);
1251         if (IS_ERR(dentry)) {
1252                 err = PTR_ERR(dentry);
1253                 goto out_unlock_dir;
1254         }
1255
1256         if (!dentry->d_inode) {
1257                 err = -ENOENT;
1258                 goto out_dput;
1259         }
1260
1261         inode = dentry->d_inode;
1262         if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
1263                 err = -EINVAL;
1264                 goto out_dput;
1265         }
1266
1267         dest = BTRFS_I(inode)->root;
1268
1269         mutex_lock(&inode->i_mutex);
1270         err = d_invalidate(dentry);
1271         if (err)
1272                 goto out_unlock;
1273
1274         down_write(&root->fs_info->subvol_sem);
1275
1276         err = may_destroy_subvol(dest);
1277         if (err)
1278                 goto out_up_write;
1279
1280         trans = btrfs_start_transaction(root, 0);
1281         if (IS_ERR(trans)) {
1282                 err = PTR_ERR(trans);
1283                 goto out_up_write;
1284         }
1285         trans->block_rsv = &root->fs_info->global_block_rsv;
1286
1287         ret = btrfs_unlink_subvol(trans, root, dir,
1288                                 dest->root_key.objectid,
1289                                 dentry->d_name.name,
1290                                 dentry->d_name.len);
1291         BUG_ON(ret);
1292
1293         btrfs_record_root_in_trans(trans, dest);
1294
1295         memset(&dest->root_item.drop_progress, 0,
1296                 sizeof(dest->root_item.drop_progress));
1297         dest->root_item.drop_level = 0;
1298         btrfs_set_root_refs(&dest->root_item, 0);
1299
1300         if (!xchg(&dest->orphan_item_inserted, 1)) {
1301                 ret = btrfs_insert_orphan_item(trans,
1302                                         root->fs_info->tree_root,
1303                                         dest->root_key.objectid);
1304                 BUG_ON(ret);
1305         }
1306
1307         ret = btrfs_commit_transaction(trans, root);
1308         BUG_ON(ret);
1309         inode->i_flags |= S_DEAD;
1310 out_up_write:
1311         up_write(&root->fs_info->subvol_sem);
1312 out_unlock:
1313         mutex_unlock(&inode->i_mutex);
1314         if (!err) {
1315                 shrink_dcache_sb(root->fs_info->sb);
1316                 btrfs_invalidate_inodes(dest);
1317                 d_delete(dentry);
1318         }
1319 out_dput:
1320         dput(dentry);
1321 out_unlock_dir:
1322         mutex_unlock(&dir->i_mutex);
1323         mnt_drop_write(file->f_path.mnt);
1324 out:
1325         kfree(vol_args);
1326         return err;
1327 }
1328
1329 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
1330 {
1331         struct inode *inode = fdentry(file)->d_inode;
1332         struct btrfs_root *root = BTRFS_I(inode)->root;
1333         struct btrfs_ioctl_defrag_range_args *range;
1334         int ret;
1335
1336         ret = mnt_want_write(file->f_path.mnt);
1337         if (ret)
1338                 return ret;
1339
1340         switch (inode->i_mode & S_IFMT) {
1341         case S_IFDIR:
1342                 if (!capable(CAP_SYS_ADMIN)) {
1343                         ret = -EPERM;
1344                         goto out;
1345                 }
1346                 ret = btrfs_defrag_root(root, 0);
1347                 if (ret)
1348                         goto out;
1349                 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
1350                 break;
1351         case S_IFREG:
1352                 if (!(file->f_mode & FMODE_WRITE)) {
1353                         ret = -EINVAL;
1354                         goto out;
1355                 }
1356
1357                 range = kzalloc(sizeof(*range), GFP_KERNEL);
1358                 if (!range) {
1359                         ret = -ENOMEM;
1360                         goto out;
1361                 }
1362
1363                 if (argp) {
1364                         if (copy_from_user(range, argp,
1365                                            sizeof(*range))) {
1366                                 ret = -EFAULT;
1367                                 kfree(range);
1368                                 goto out;
1369                         }
1370                         /* compression requires us to start the IO */
1371                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1372                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
1373                                 range->extent_thresh = (u32)-1;
1374                         }
1375                 } else {
1376                         /* the rest are all set to zero by kzalloc */
1377                         range->len = (u64)-1;
1378                 }
1379                 ret = btrfs_defrag_file(file, range);
1380                 kfree(range);
1381                 break;
1382         default:
1383                 ret = -EINVAL;
1384         }
1385 out:
1386         mnt_drop_write(file->f_path.mnt);
1387         return ret;
1388 }
1389
1390 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
1391 {
1392         struct btrfs_ioctl_vol_args *vol_args;
1393         int ret;
1394
1395         if (!capable(CAP_SYS_ADMIN))
1396                 return -EPERM;
1397
1398         vol_args = memdup_user(arg, sizeof(*vol_args));
1399         if (IS_ERR(vol_args))
1400                 return PTR_ERR(vol_args);
1401
1402         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1403         ret = btrfs_init_new_device(root, vol_args->name);
1404
1405         kfree(vol_args);
1406         return ret;
1407 }
1408
1409 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
1410 {
1411         struct btrfs_ioctl_vol_args *vol_args;
1412         int ret;
1413
1414         if (!capable(CAP_SYS_ADMIN))
1415                 return -EPERM;
1416
1417         if (root->fs_info->sb->s_flags & MS_RDONLY)
1418                 return -EROFS;
1419
1420         vol_args = memdup_user(arg, sizeof(*vol_args));
1421         if (IS_ERR(vol_args))
1422                 return PTR_ERR(vol_args);
1423
1424         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1425         ret = btrfs_rm_device(root, vol_args->name);
1426
1427         kfree(vol_args);
1428         return ret;
1429 }
1430
1431 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
1432                                        u64 off, u64 olen, u64 destoff)
1433 {
1434         struct inode *inode = fdentry(file)->d_inode;
1435         struct btrfs_root *root = BTRFS_I(inode)->root;
1436         struct file *src_file;
1437         struct inode *src;
1438         struct btrfs_trans_handle *trans;
1439         struct btrfs_path *path;
1440         struct extent_buffer *leaf;
1441         char *buf;
1442         struct btrfs_key key;
1443         u32 nritems;
1444         int slot;
1445         int ret;
1446         u64 len = olen;
1447         u64 bs = root->fs_info->sb->s_blocksize;
1448         u64 hint_byte;
1449
1450         /*
1451          * TODO:
1452          * - split compressed inline extents.  annoying: we need to
1453          *   decompress into destination's address_space (the file offset
1454          *   may change, so source mapping won't do), then recompress (or
1455          *   otherwise reinsert) a subrange.
1456          * - allow ranges within the same file to be cloned (provided
1457          *   they don't overlap)?
1458          */
1459
1460         /* the destination must be opened for writing */
1461         if (!(file->f_mode & FMODE_WRITE))
1462                 return -EINVAL;
1463
1464         ret = mnt_want_write(file->f_path.mnt);
1465         if (ret)
1466                 return ret;
1467
1468         src_file = fget(srcfd);
1469         if (!src_file) {
1470                 ret = -EBADF;
1471                 goto out_drop_write;
1472         }
1473
1474         src = src_file->f_dentry->d_inode;
1475
1476         ret = -EINVAL;
1477         if (src == inode)
1478                 goto out_fput;
1479
1480         /* the src must be open for reading */
1481         if (!(src_file->f_mode & FMODE_READ))
1482                 goto out_fput;
1483
1484         ret = -EISDIR;
1485         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
1486                 goto out_fput;
1487
1488         ret = -EXDEV;
1489         if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
1490                 goto out_fput;
1491
1492         ret = -ENOMEM;
1493         buf = vmalloc(btrfs_level_size(root, 0));
1494         if (!buf)
1495                 goto out_fput;
1496
1497         path = btrfs_alloc_path();
1498         if (!path) {
1499                 vfree(buf);
1500                 goto out_fput;
1501         }
1502         path->reada = 2;
1503
1504         if (inode < src) {
1505                 mutex_lock(&inode->i_mutex);
1506                 mutex_lock(&src->i_mutex);
1507         } else {
1508                 mutex_lock(&src->i_mutex);
1509                 mutex_lock(&inode->i_mutex);
1510         }
1511
1512         /* determine range to clone */
1513         ret = -EINVAL;
1514         if (off >= src->i_size || off + len > src->i_size)
1515                 goto out_unlock;
1516         if (len == 0)
1517                 olen = len = src->i_size - off;
1518         /* if we extend to eof, continue to block boundary */
1519         if (off + len == src->i_size)
1520                 len = ((src->i_size + bs-1) & ~(bs-1))
1521                         - off;
1522
1523         /* verify the end result is block aligned */
1524         if ((off & (bs-1)) ||
1525             ((off + len) & (bs-1)))
1526                 goto out_unlock;
1527
1528         /* do any pending delalloc/csum calc on src, one way or
1529            another, and lock file content */
1530         while (1) {
1531                 struct btrfs_ordered_extent *ordered;
1532                 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1533                 ordered = btrfs_lookup_first_ordered_extent(inode, off+len);
1534                 if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered)
1535                         break;
1536                 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1537                 if (ordered)
1538                         btrfs_put_ordered_extent(ordered);
1539                 btrfs_wait_ordered_range(src, off, off+len);
1540         }
1541
1542         /* clone data */
1543         key.objectid = src->i_ino;
1544         key.type = BTRFS_EXTENT_DATA_KEY;
1545         key.offset = 0;
1546
1547         while (1) {
1548                 /*
1549                  * note the key will change type as we walk through the
1550                  * tree.
1551                  */
1552                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1553                 if (ret < 0)
1554                         goto out;
1555
1556                 nritems = btrfs_header_nritems(path->nodes[0]);
1557                 if (path->slots[0] >= nritems) {
1558                         ret = btrfs_next_leaf(root, path);
1559                         if (ret < 0)
1560                                 goto out;
1561                         if (ret > 0)
1562                                 break;
1563                         nritems = btrfs_header_nritems(path->nodes[0]);
1564                 }
1565                 leaf = path->nodes[0];
1566                 slot = path->slots[0];
1567
1568                 btrfs_item_key_to_cpu(leaf, &key, slot);
1569                 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
1570                     key.objectid != src->i_ino)
1571                         break;
1572
1573                 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
1574                         struct btrfs_file_extent_item *extent;
1575                         int type;
1576                         u32 size;
1577                         struct btrfs_key new_key;
1578                         u64 disko = 0, diskl = 0;
1579                         u64 datao = 0, datal = 0;
1580                         u8 comp;
1581
1582                         size = btrfs_item_size_nr(leaf, slot);
1583                         read_extent_buffer(leaf, buf,
1584                                            btrfs_item_ptr_offset(leaf, slot),
1585                                            size);
1586
1587                         extent = btrfs_item_ptr(leaf, slot,
1588                                                 struct btrfs_file_extent_item);
1589                         comp = btrfs_file_extent_compression(leaf, extent);
1590                         type = btrfs_file_extent_type(leaf, extent);
1591                         if (type == BTRFS_FILE_EXTENT_REG ||
1592                             type == BTRFS_FILE_EXTENT_PREALLOC) {
1593                                 disko = btrfs_file_extent_disk_bytenr(leaf,
1594                                                                       extent);
1595                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
1596                                                                  extent);
1597                                 datao = btrfs_file_extent_offset(leaf, extent);
1598                                 datal = btrfs_file_extent_num_bytes(leaf,
1599                                                                     extent);
1600                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
1601                                 /* take upper bound, may be compressed */
1602                                 datal = btrfs_file_extent_ram_bytes(leaf,
1603                                                                     extent);
1604                         }
1605                         btrfs_release_path(root, path);
1606
1607                         if (key.offset + datal < off ||
1608                             key.offset >= off+len)
1609                                 goto next;
1610
1611                         memcpy(&new_key, &key, sizeof(new_key));
1612                         new_key.objectid = inode->i_ino;
1613                         new_key.offset = key.offset + destoff - off;
1614
1615                         trans = btrfs_start_transaction(root, 1);
1616                         if (IS_ERR(trans)) {
1617                                 ret = PTR_ERR(trans);
1618                                 goto out;
1619                         }
1620
1621                         if (type == BTRFS_FILE_EXTENT_REG ||
1622                             type == BTRFS_FILE_EXTENT_PREALLOC) {
1623                                 if (off > key.offset) {
1624                                         datao += off - key.offset;
1625                                         datal -= off - key.offset;
1626                                 }
1627
1628                                 if (key.offset + datal > off + len)
1629                                         datal = off + len - key.offset;
1630
1631                                 ret = btrfs_drop_extents(trans, inode,
1632                                                          new_key.offset,
1633                                                          new_key.offset + datal,
1634                                                          &hint_byte, 1);
1635                                 BUG_ON(ret);
1636
1637                                 ret = btrfs_insert_empty_item(trans, root, path,
1638                                                               &new_key, size);
1639                                 BUG_ON(ret);
1640
1641                                 leaf = path->nodes[0];
1642                                 slot = path->slots[0];
1643                                 write_extent_buffer(leaf, buf,
1644                                             btrfs_item_ptr_offset(leaf, slot),
1645                                             size);
1646
1647                                 extent = btrfs_item_ptr(leaf, slot,
1648                                                 struct btrfs_file_extent_item);
1649
1650                                 /* disko == 0 means it's a hole */
1651                                 if (!disko)
1652                                         datao = 0;
1653
1654                                 btrfs_set_file_extent_offset(leaf, extent,
1655                                                              datao);
1656                                 btrfs_set_file_extent_num_bytes(leaf, extent,
1657                                                                 datal);
1658                                 if (disko) {
1659                                         inode_add_bytes(inode, datal);
1660                                         ret = btrfs_inc_extent_ref(trans, root,
1661                                                         disko, diskl, 0,
1662                                                         root->root_key.objectid,
1663                                                         inode->i_ino,
1664                                                         new_key.offset - datao);
1665                                         BUG_ON(ret);
1666                                 }
1667                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
1668                                 u64 skip = 0;
1669                                 u64 trim = 0;
1670                                 if (off > key.offset) {
1671                                         skip = off - key.offset;
1672                                         new_key.offset += skip;
1673                                 }
1674
1675                                 if (key.offset + datal > off+len)
1676                                         trim = key.offset + datal - (off+len);
1677
1678                                 if (comp && (skip || trim)) {
1679                                         ret = -EINVAL;
1680                                         btrfs_end_transaction(trans, root);
1681                                         goto out;
1682                                 }
1683                                 size -= skip + trim;
1684                                 datal -= skip + trim;
1685
1686                                 ret = btrfs_drop_extents(trans, inode,
1687                                                          new_key.offset,
1688                                                          new_key.offset + datal,
1689                                                          &hint_byte, 1);
1690                                 BUG_ON(ret);
1691
1692                                 ret = btrfs_insert_empty_item(trans, root, path,
1693                                                               &new_key, size);
1694                                 BUG_ON(ret);
1695
1696                                 if (skip) {
1697                                         u32 start =
1698                                           btrfs_file_extent_calc_inline_size(0);
1699                                         memmove(buf+start, buf+start+skip,
1700                                                 datal);
1701                                 }
1702
1703                                 leaf = path->nodes[0];
1704                                 slot = path->slots[0];
1705                                 write_extent_buffer(leaf, buf,
1706                                             btrfs_item_ptr_offset(leaf, slot),
1707                                             size);
1708                                 inode_add_bytes(inode, datal);
1709                         }
1710
1711                         btrfs_mark_buffer_dirty(leaf);
1712                         btrfs_release_path(root, path);
1713
1714                         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1715                         if (new_key.offset + datal > inode->i_size)
1716                                 btrfs_i_size_write(inode,
1717                                                    new_key.offset + datal);
1718                         BTRFS_I(inode)->flags = BTRFS_I(src)->flags;
1719                         ret = btrfs_update_inode(trans, root, inode);
1720                         BUG_ON(ret);
1721                         btrfs_end_transaction(trans, root);
1722                 }
1723 next:
1724                 btrfs_release_path(root, path);
1725                 key.offset++;
1726         }
1727         ret = 0;
1728 out:
1729         btrfs_release_path(root, path);
1730         unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1731 out_unlock:
1732         mutex_unlock(&src->i_mutex);
1733         mutex_unlock(&inode->i_mutex);
1734         vfree(buf);
1735         btrfs_free_path(path);
1736 out_fput:
1737         fput(src_file);
1738 out_drop_write:
1739         mnt_drop_write(file->f_path.mnt);
1740         return ret;
1741 }
1742
1743 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
1744 {
1745         struct btrfs_ioctl_clone_range_args args;
1746
1747         if (copy_from_user(&args, argp, sizeof(args)))
1748                 return -EFAULT;
1749         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
1750                                  args.src_length, args.dest_offset);
1751 }
1752
1753 /*
1754  * there are many ways the trans_start and trans_end ioctls can lead
1755  * to deadlocks.  They should only be used by applications that
1756  * basically own the machine, and have a very in depth understanding
1757  * of all the possible deadlocks and enospc problems.
1758  */
1759 static long btrfs_ioctl_trans_start(struct file *file)
1760 {
1761         struct inode *inode = fdentry(file)->d_inode;
1762         struct btrfs_root *root = BTRFS_I(inode)->root;
1763         struct btrfs_trans_handle *trans;
1764         int ret;
1765
1766         ret = -EPERM;
1767         if (!capable(CAP_SYS_ADMIN))
1768                 goto out;
1769
1770         ret = -EINPROGRESS;
1771         if (file->private_data)
1772                 goto out;
1773
1774         ret = mnt_want_write(file->f_path.mnt);
1775         if (ret)
1776                 goto out;
1777
1778         mutex_lock(&root->fs_info->trans_mutex);
1779         root->fs_info->open_ioctl_trans++;
1780         mutex_unlock(&root->fs_info->trans_mutex);
1781
1782         ret = -ENOMEM;
1783         trans = btrfs_start_ioctl_transaction(root, 0);
1784         if (!trans)
1785                 goto out_drop;
1786
1787         file->private_data = trans;
1788         return 0;
1789
1790 out_drop:
1791         mutex_lock(&root->fs_info->trans_mutex);
1792         root->fs_info->open_ioctl_trans--;
1793         mutex_unlock(&root->fs_info->trans_mutex);
1794         mnt_drop_write(file->f_path.mnt);
1795 out:
1796         return ret;
1797 }
1798
1799 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
1800 {
1801         struct inode *inode = fdentry(file)->d_inode;
1802         struct btrfs_root *root = BTRFS_I(inode)->root;
1803         struct btrfs_root *new_root;
1804         struct btrfs_dir_item *di;
1805         struct btrfs_trans_handle *trans;
1806         struct btrfs_path *path;
1807         struct btrfs_key location;
1808         struct btrfs_disk_key disk_key;
1809         struct btrfs_super_block *disk_super;
1810         u64 features;
1811         u64 objectid = 0;
1812         u64 dir_id;
1813
1814         if (!capable(CAP_SYS_ADMIN))
1815                 return -EPERM;
1816
1817         if (copy_from_user(&objectid, argp, sizeof(objectid)))
1818                 return -EFAULT;
1819
1820         if (!objectid)
1821                 objectid = root->root_key.objectid;
1822
1823         location.objectid = objectid;
1824         location.type = BTRFS_ROOT_ITEM_KEY;
1825         location.offset = (u64)-1;
1826
1827         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
1828         if (IS_ERR(new_root))
1829                 return PTR_ERR(new_root);
1830
1831         if (btrfs_root_refs(&new_root->root_item) == 0)
1832                 return -ENOENT;
1833
1834         path = btrfs_alloc_path();
1835         if (!path)
1836                 return -ENOMEM;
1837         path->leave_spinning = 1;
1838
1839         trans = btrfs_start_transaction(root, 1);
1840         if (!trans) {
1841                 btrfs_free_path(path);
1842                 return -ENOMEM;
1843         }
1844
1845         dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
1846         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
1847                                    dir_id, "default", 7, 1);
1848         if (IS_ERR_OR_NULL(di)) {
1849                 btrfs_free_path(path);
1850                 btrfs_end_transaction(trans, root);
1851                 printk(KERN_ERR "Umm, you don't have the default dir item, "
1852                        "this isn't going to work\n");
1853                 return -ENOENT;
1854         }
1855
1856         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
1857         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
1858         btrfs_mark_buffer_dirty(path->nodes[0]);
1859         btrfs_free_path(path);
1860
1861         disk_super = &root->fs_info->super_copy;
1862         features = btrfs_super_incompat_flags(disk_super);
1863         if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
1864                 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
1865                 btrfs_set_super_incompat_flags(disk_super, features);
1866         }
1867         btrfs_end_transaction(trans, root);
1868
1869         return 0;
1870 }
1871
1872 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
1873 {
1874         struct btrfs_ioctl_space_args space_args;
1875         struct btrfs_ioctl_space_info space;
1876         struct btrfs_ioctl_space_info *dest;
1877         struct btrfs_ioctl_space_info *dest_orig;
1878         struct btrfs_ioctl_space_info *user_dest;
1879         struct btrfs_space_info *info;
1880         int alloc_size;
1881         int ret = 0;
1882         int slot_count = 0;
1883
1884         if (copy_from_user(&space_args,
1885                            (struct btrfs_ioctl_space_args __user *)arg,
1886                            sizeof(space_args)))
1887                 return -EFAULT;
1888
1889         /* first we count slots */
1890         rcu_read_lock();
1891         list_for_each_entry_rcu(info, &root->fs_info->space_info, list)
1892                 slot_count++;
1893         rcu_read_unlock();
1894
1895         /* space_slots == 0 means they are asking for a count */
1896         if (space_args.space_slots == 0) {
1897                 space_args.total_spaces = slot_count;
1898                 goto out;
1899         }
1900         alloc_size = sizeof(*dest) * slot_count;
1901         /* we generally have at most 6 or so space infos, one for each raid
1902          * level.  So, a whole page should be more than enough for everyone
1903          */
1904         if (alloc_size > PAGE_CACHE_SIZE)
1905                 return -ENOMEM;
1906
1907         space_args.total_spaces = 0;
1908         dest = kmalloc(alloc_size, GFP_NOFS);
1909         if (!dest)
1910                 return -ENOMEM;
1911         dest_orig = dest;
1912
1913         /* now we have a buffer to copy into */
1914         rcu_read_lock();
1915         list_for_each_entry_rcu(info, &root->fs_info->space_info, list) {
1916                 /* make sure we don't copy more than we allocated
1917                  * in our buffer
1918                  */
1919                 if (slot_count == 0)
1920                         break;
1921                 slot_count--;
1922
1923                 /* make sure userland has enough room in their buffer */
1924                 if (space_args.total_spaces >= space_args.space_slots)
1925                         break;
1926
1927                 space.flags = info->flags;
1928                 space.total_bytes = info->total_bytes;
1929                 space.used_bytes = info->bytes_used;
1930                 memcpy(dest, &space, sizeof(space));
1931                 dest++;
1932                 space_args.total_spaces++;
1933         }
1934         rcu_read_unlock();
1935
1936         user_dest = (struct btrfs_ioctl_space_info *)
1937                 (arg + sizeof(struct btrfs_ioctl_space_args));
1938
1939         if (copy_to_user(user_dest, dest_orig, alloc_size))
1940                 ret = -EFAULT;
1941
1942         kfree(dest_orig);
1943 out:
1944         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
1945                 ret = -EFAULT;
1946
1947         return ret;
1948 }
1949
1950 /*
1951  * there are many ways the trans_start and trans_end ioctls can lead
1952  * to deadlocks.  They should only be used by applications that
1953  * basically own the machine, and have a very in depth understanding
1954  * of all the possible deadlocks and enospc problems.
1955  */
1956 long btrfs_ioctl_trans_end(struct file *file)
1957 {
1958         struct inode *inode = fdentry(file)->d_inode;
1959         struct btrfs_root *root = BTRFS_I(inode)->root;
1960         struct btrfs_trans_handle *trans;
1961
1962         trans = file->private_data;
1963         if (!trans)
1964                 return -EINVAL;
1965         file->private_data = NULL;
1966
1967         btrfs_end_transaction(trans, root);
1968
1969         mutex_lock(&root->fs_info->trans_mutex);
1970         root->fs_info->open_ioctl_trans--;
1971         mutex_unlock(&root->fs_info->trans_mutex);
1972
1973         mnt_drop_write(file->f_path.mnt);
1974         return 0;
1975 }
1976
1977 long btrfs_ioctl(struct file *file, unsigned int
1978                 cmd, unsigned long arg)
1979 {
1980         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1981         void __user *argp = (void __user *)arg;
1982
1983         switch (cmd) {
1984         case FS_IOC_GETFLAGS:
1985                 return btrfs_ioctl_getflags(file, argp);
1986         case FS_IOC_SETFLAGS:
1987                 return btrfs_ioctl_setflags(file, argp);
1988         case FS_IOC_GETVERSION:
1989                 return btrfs_ioctl_getversion(file, argp);
1990         case BTRFS_IOC_SNAP_CREATE:
1991                 return btrfs_ioctl_snap_create(file, argp, 0);
1992         case BTRFS_IOC_SUBVOL_CREATE:
1993                 return btrfs_ioctl_snap_create(file, argp, 1);
1994         case BTRFS_IOC_SNAP_DESTROY:
1995                 return btrfs_ioctl_snap_destroy(file, argp);
1996         case BTRFS_IOC_DEFAULT_SUBVOL:
1997                 return btrfs_ioctl_default_subvol(file, argp);
1998         case BTRFS_IOC_DEFRAG:
1999                 return btrfs_ioctl_defrag(file, NULL);
2000         case BTRFS_IOC_DEFRAG_RANGE:
2001                 return btrfs_ioctl_defrag(file, argp);
2002         case BTRFS_IOC_RESIZE:
2003                 return btrfs_ioctl_resize(root, argp);
2004         case BTRFS_IOC_ADD_DEV:
2005                 return btrfs_ioctl_add_dev(root, argp);
2006         case BTRFS_IOC_RM_DEV:
2007                 return btrfs_ioctl_rm_dev(root, argp);
2008         case BTRFS_IOC_BALANCE:
2009                 return btrfs_balance(root->fs_info->dev_root);
2010         case BTRFS_IOC_CLONE:
2011                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
2012         case BTRFS_IOC_CLONE_RANGE:
2013                 return btrfs_ioctl_clone_range(file, argp);
2014         case BTRFS_IOC_TRANS_START:
2015                 return btrfs_ioctl_trans_start(file);
2016         case BTRFS_IOC_TRANS_END:
2017                 return btrfs_ioctl_trans_end(file);
2018         case BTRFS_IOC_TREE_SEARCH:
2019                 return btrfs_ioctl_tree_search(file, argp);
2020         case BTRFS_IOC_INO_LOOKUP:
2021                 return btrfs_ioctl_ino_lookup(file, argp);
2022         case BTRFS_IOC_SPACE_INFO:
2023                 return btrfs_ioctl_space_info(root, argp);
2024         case BTRFS_IOC_SYNC:
2025                 btrfs_sync_fs(file->f_dentry->d_sb, 1);
2026                 return 0;
2027         }
2028
2029         return -ENOTTY;
2030 }