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 <linux/blkdev.h>
  44 #include "compat.h"
  45 #include "ctree.h"
  46 #include "disk-io.h"
  47 #include "transaction.h"
  48 #include "btrfs_inode.h"
  49 #include "ioctl.h"
  50 #include "print-tree.h"
  51 #include "volumes.h"
  52 #include "locking.h"
  53 #include "inode-map.h"
  54 #include "backref.h"
  55
  56 /* Mask out flags that are inappropriate for the given type of inode. */
  57 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
  58 {
  59         if (S_ISDIR(mode))
  60                 return flags;
  61         else if (S_ISREG(mode))
  62                 return flags & ~FS_DIRSYNC_FL;
  63         else
  64                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
  65 }
  66
  67 /*
  68  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
  69  */
  70 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
  71 {
  72         unsigned int iflags = 0;
  73
  74         if (flags & BTRFS_INODE_SYNC)
  75                 iflags |= FS_SYNC_FL;
  76         if (flags & BTRFS_INODE_IMMUTABLE)
  77                 iflags |= FS_IMMUTABLE_FL;
  78         if (flags & BTRFS_INODE_APPEND)
  79                 iflags |= FS_APPEND_FL;
  80         if (flags & BTRFS_INODE_NODUMP)
  81                 iflags |= FS_NODUMP_FL;
  82         if (flags & BTRFS_INODE_NOATIME)
  83                 iflags |= FS_NOATIME_FL;
  84         if (flags & BTRFS_INODE_DIRSYNC)
  85                 iflags |= FS_DIRSYNC_FL;
  86         if (flags & BTRFS_INODE_NODATACOW)
  87                 iflags |= FS_NOCOW_FL;
  88
  89         if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
  90                 iflags |= FS_COMPR_FL;
  91         else if (flags & BTRFS_INODE_NOCOMPRESS)
  92                 iflags |= FS_NOCOMP_FL;
  93
  94         return iflags;
  95 }
  96
  97 /*
  98  * Update inode->i_flags based on the btrfs internal flags.
  99  */
 100 void btrfs_update_iflags(struct inode *inode)
 101 {
 102         struct btrfs_inode *ip = BTRFS_I(inode);
 103
 104         inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
 105
 106         if (ip->flags & BTRFS_INODE_SYNC)
 107                 inode->i_flags |= S_SYNC;
 108         if (ip->flags & BTRFS_INODE_IMMUTABLE)
 109                 inode->i_flags |= S_IMMUTABLE;
 110         if (ip->flags & BTRFS_INODE_APPEND)
 111                 inode->i_flags |= S_APPEND;
 112         if (ip->flags & BTRFS_INODE_NOATIME)
 113                 inode->i_flags |= S_NOATIME;
 114         if (ip->flags & BTRFS_INODE_DIRSYNC)
 115                 inode->i_flags |= S_DIRSYNC;
 116 }
 117
 118 /*
 119  * Inherit flags from the parent inode.
 120  *
 121  * Currently only the compression flags and the cow flags are inherited.
 122  */
 123 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 124 {
 125         unsigned int flags;
 126
 127         if (!dir)
 128                 return;
 129
 130         flags = BTRFS_I(dir)->flags;
 131
 132         if (flags & BTRFS_INODE_NOCOMPRESS) {
 133                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 134                 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 135         } else if (flags & BTRFS_INODE_COMPRESS) {
 136                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 137                 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 138         }
 139
 140         if (flags & BTRFS_INODE_NODATACOW)
 141                 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 142
 143         btrfs_update_iflags(inode);
 144 }
 145
 146 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 147 {
 148         struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
 149         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 150
 151         if (copy_to_user(arg, &flags, sizeof(flags)))
 152                 return -EFAULT;
 153         return 0;
 154 }
 155
 156 static int check_flags(unsigned int flags)
 157 {
 158         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 159                       FS_NOATIME_FL | FS_NODUMP_FL | \
 160                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 161                       FS_NOCOMP_FL | FS_COMPR_FL |
 162                       FS_NOCOW_FL))
 163                 return -EOPNOTSUPP;
 164
 165         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 166                 return -EINVAL;
 167
 168         return 0;
 169 }
 170
 171 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 172 {
 173         struct inode *inode = file->f_path.dentry->d_inode;
 174         struct btrfs_inode *ip = BTRFS_I(inode);
 175         struct btrfs_root *root = ip->root;
 176         struct btrfs_trans_handle *trans;
 177         unsigned int flags, oldflags;
 178         int ret;
 179         u64 ip_oldflags;
 180         unsigned int i_oldflags;
 181
 182         if (btrfs_root_readonly(root))
 183                 return -EROFS;
 184
 185         if (copy_from_user(&flags, arg, sizeof(flags)))
 186                 return -EFAULT;
 187
 188         ret = check_flags(flags);
 189         if (ret)
 190                 return ret;
 191
 192         if (!inode_owner_or_capable(inode))
 193                 return -EACCES;
 194
 195         mutex_lock(&inode->i_mutex);
 196
 197         ip_oldflags = ip->flags;
 198         i_oldflags = inode->i_flags;
 199
 200         flags = btrfs_mask_flags(inode->i_mode, flags);
 201         oldflags = btrfs_flags_to_ioctl(ip->flags);
 202         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 203                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 204                         ret = -EPERM;
 205                         goto out_unlock;
 206                 }
 207         }
 208
 209         ret = mnt_want_write(file->f_path.mnt);
 210         if (ret)
 211                 goto out_unlock;
 212
 213         if (flags & FS_SYNC_FL)
 214                 ip->flags |= BTRFS_INODE_SYNC;
 215         else
 216                 ip->flags &= ~BTRFS_INODE_SYNC;
 217         if (flags & FS_IMMUTABLE_FL)
 218                 ip->flags |= BTRFS_INODE_IMMUTABLE;
 219         else
 220                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 221         if (flags & FS_APPEND_FL)
 222                 ip->flags |= BTRFS_INODE_APPEND;
 223         else
 224                 ip->flags &= ~BTRFS_INODE_APPEND;
 225         if (flags & FS_NODUMP_FL)
 226                 ip->flags |= BTRFS_INODE_NODUMP;
 227         else
 228                 ip->flags &= ~BTRFS_INODE_NODUMP;
 229         if (flags & FS_NOATIME_FL)
 230                 ip->flags |= BTRFS_INODE_NOATIME;
 231         else
 232                 ip->flags &= ~BTRFS_INODE_NOATIME;
 233         if (flags & FS_DIRSYNC_FL)
 234                 ip->flags |= BTRFS_INODE_DIRSYNC;
 235         else
 236                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
 237         if (flags & FS_NOCOW_FL)
 238                 ip->flags |= BTRFS_INODE_NODATACOW;
 239         else
 240                 ip->flags &= ~BTRFS_INODE_NODATACOW;
 241
 242         /*
 243          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 244          * flag may be changed automatically if compression code won't make
 245          * things smaller.
 246          */
 247         if (flags & FS_NOCOMP_FL) {
 248                 ip->flags &= ~BTRFS_INODE_COMPRESS;
 249                 ip->flags |= BTRFS_INODE_NOCOMPRESS;
 250         } else if (flags & FS_COMPR_FL) {
 251                 ip->flags |= BTRFS_INODE_COMPRESS;
 252                 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 253         } else {
 254                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 255         }
 256
 257         trans = btrfs_start_transaction(root, 1);
 258         if (IS_ERR(trans)) {
 259                 ret = PTR_ERR(trans);
 260                 goto out_drop;
 261         }
 262
 263         btrfs_update_iflags(inode);
 264         inode->i_ctime = CURRENT_TIME;
 265         ret = btrfs_update_inode(trans, root, inode);
 266
 267         btrfs_end_transaction(trans, root);
 268  out_drop:
 269         if (ret) {
 270                 ip->flags = ip_oldflags;
 271                 inode->i_flags = i_oldflags;
 272         }
 273
 274         mnt_drop_write(file->f_path.mnt);
 275  out_unlock:
 276         mutex_unlock(&inode->i_mutex);
 277         return ret;
 278 }
 279
 280 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 281 {
 282         struct inode *inode = file->f_path.dentry->d_inode;
 283
 284         return put_user(inode->i_generation, arg);
 285 }
 286
 287 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 288 {
 289         struct btrfs_root *root = fdentry(file)->d_sb->s_fs_info;
 290         struct btrfs_fs_info *fs_info = root->fs_info;
 291         struct btrfs_device *device;
 292         struct request_queue *q;
 293         struct fstrim_range range;
 294         u64 minlen = ULLONG_MAX;
 295         u64 num_devices = 0;
 296         u64 total_bytes = btrfs_super_total_bytes(root->fs_info->super_copy);
 297         int ret;
 298
 299         if (!capable(CAP_SYS_ADMIN))
 300                 return -EPERM;
 301
 302         rcu_read_lock();
 303         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 304                                 dev_list) {
 305                 if (!device->bdev)
 306                         continue;
 307                 q = bdev_get_queue(device->bdev);
 308                 if (blk_queue_discard(q)) {
 309                         num_devices++;
 310                         minlen = min((u64)q->limits.discard_granularity,
 311                                      minlen);
 312                 }
 313         }
 314         rcu_read_unlock();
 315
 316         if (!num_devices)
 317                 return -EOPNOTSUPP;
 318         if (copy_from_user(&range, arg, sizeof(range)))
 319                 return -EFAULT;
 320         if (range.start > total_bytes)
 321                 return -EINVAL;
 322
 323         range.len = min(range.len, total_bytes - range.start);
 324         range.minlen = max(range.minlen, minlen);
 325         ret = btrfs_trim_fs(root, &range);
 326         if (ret < 0)
 327                 return ret;
 328
 329         if (copy_to_user(arg, &range, sizeof(range)))
 330                 return -EFAULT;
 331
 332         return 0;
 333 }
 334
 335 static noinline int create_subvol(struct btrfs_root *root,
 336                                   struct dentry *dentry,
 337                                   char *name, int namelen,
 338                                   u64 *async_transid)
 339 {
 340         struct btrfs_trans_handle *trans;
 341         struct btrfs_key key;
 342         struct btrfs_root_item root_item;
 343         struct btrfs_inode_item *inode_item;
 344         struct extent_buffer *leaf;
 345         struct btrfs_root *new_root;
 346         struct dentry *parent = dentry->d_parent;
 347         struct inode *dir;
 348         int ret;
 349         int err;
 350         u64 objectid;
 351         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 352         u64 index = 0;
 353
 354         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 355         if (ret)
 356                 return ret;
 357
 358         dir = parent->d_inode;
 359
 360         /*
 361          * 1 - inode item
 362          * 2 - refs
 363          * 1 - root item
 364          * 2 - dir items
 365          */
 366         trans = btrfs_start_transaction(root, 6);
 367         if (IS_ERR(trans))
 368                 return PTR_ERR(trans);
 369
 370         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
 371                                       0, objectid, NULL, 0, 0, 0, 0);
 372         if (IS_ERR(leaf)) {
 373                 ret = PTR_ERR(leaf);
 374                 goto fail;
 375         }
 376
 377         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 378         btrfs_set_header_bytenr(leaf, leaf->start);
 379         btrfs_set_header_generation(leaf, trans->transid);
 380         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 381         btrfs_set_header_owner(leaf, objectid);
 382
 383         write_extent_buffer(leaf, root->fs_info->fsid,
 384                             (unsigned long)btrfs_header_fsid(leaf),
 385                             BTRFS_FSID_SIZE);
 386         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 387                             (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
 388                             BTRFS_UUID_SIZE);
 389         btrfs_mark_buffer_dirty(leaf);
 390
 391         inode_item = &root_item.inode;
 392         memset(inode_item, 0, sizeof(*inode_item));
 393         inode_item->generation = cpu_to_le64(1);
 394         inode_item->size = cpu_to_le64(3);
 395         inode_item->nlink = cpu_to_le32(1);
 396         inode_item->nbytes = cpu_to_le64(root->leafsize);
 397         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 398
 399         root_item.flags = 0;
 400         root_item.byte_limit = 0;
 401         inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
 402
 403         btrfs_set_root_bytenr(&root_item, leaf->start);
 404         btrfs_set_root_generation(&root_item, trans->transid);
 405         btrfs_set_root_level(&root_item, 0);
 406         btrfs_set_root_refs(&root_item, 1);
 407         btrfs_set_root_used(&root_item, leaf->len);
 408         btrfs_set_root_last_snapshot(&root_item, 0);
 409
 410         memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
 411         root_item.drop_level = 0;
 412
 413         btrfs_tree_unlock(leaf);
 414         free_extent_buffer(leaf);
 415         leaf = NULL;
 416
 417         btrfs_set_root_dirid(&root_item, new_dirid);
 418
 419         key.objectid = objectid;
 420         key.offset = 0;
 421         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 422         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 423                                 &root_item);
 424         if (ret)
 425                 goto fail;
 426
 427         key.offset = (u64)-1;
 428         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 429         BUG_ON(IS_ERR(new_root));
 430
 431         btrfs_record_root_in_trans(trans, new_root);
 432
 433         ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
 434         /*
 435          * insert the directory item
 436          */
 437         ret = btrfs_set_inode_index(dir, &index);
 438         BUG_ON(ret);
 439
 440         ret = btrfs_insert_dir_item(trans, root,
 441                                     name, namelen, dir, &key,
 442                                     BTRFS_FT_DIR, index);
 443         if (ret)
 444                 goto fail;
 445
 446         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 447         ret = btrfs_update_inode(trans, root, dir);
 448         BUG_ON(ret);
 449
 450         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 451                                  objectid, root->root_key.objectid,
 452                                  btrfs_ino(dir), index, name, namelen);
 453
 454         BUG_ON(ret);
 455
 456         d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 457 fail:
 458         if (async_transid) {
 459                 *async_transid = trans->transid;
 460                 err = btrfs_commit_transaction_async(trans, root, 1);
 461         } else {
 462                 err = btrfs_commit_transaction(trans, root);
 463         }
 464         if (err && !ret)
 465                 ret = err;
 466         return ret;
 467 }
 468
 469 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
 470                            char *name, int namelen, u64 *async_transid,
 471                            bool readonly)
 472 {
 473         struct inode *inode;
 474         struct btrfs_pending_snapshot *pending_snapshot;
 475         struct btrfs_trans_handle *trans;
 476         int ret;
 477
 478         if (!root->ref_cows)
 479                 return -EINVAL;
 480
 481         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 482         if (!pending_snapshot)
 483                 return -ENOMEM;
 484
 485         btrfs_init_block_rsv(&pending_snapshot->block_rsv);
 486         pending_snapshot->dentry = dentry;
 487         pending_snapshot->root = root;
 488         pending_snapshot->readonly = readonly;
 489
 490         trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
 491         if (IS_ERR(trans)) {
 492                 ret = PTR_ERR(trans);
 493                 goto fail;
 494         }
 495
 496         ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
 497         BUG_ON(ret);
 498
 499         spin_lock(&root->fs_info->trans_lock);
 500         list_add(&pending_snapshot->list,
 501                  &trans->transaction->pending_snapshots);
 502         spin_unlock(&root->fs_info->trans_lock);
 503         if (async_transid) {
 504                 *async_transid = trans->transid;
 505                 ret = btrfs_commit_transaction_async(trans,
 506                                      root->fs_info->extent_root, 1);
 507         } else {
 508                 ret = btrfs_commit_transaction(trans,
 509                                                root->fs_info->extent_root);
 510         }
 511         BUG_ON(ret);
 512
 513         ret = pending_snapshot->error;
 514         if (ret)
 515                 goto fail;
 516
 517         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 518         if (ret)
 519                 goto fail;
 520
 521         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 522         if (IS_ERR(inode)) {
 523                 ret = PTR_ERR(inode);
 524                 goto fail;
 525         }
 526         BUG_ON(!inode);
 527         d_instantiate(dentry, inode);
 528         ret = 0;
 529 fail:
 530         kfree(pending_snapshot);
 531         return ret;
 532 }
 533
 534 /*  copy of check_sticky in fs/namei.c()
 535 * It's inline, so penalty for filesystems that don't use sticky bit is
 536 * minimal.
 537 */
 538 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 539 {
 540         uid_t fsuid = current_fsuid();
 541
 542         if (!(dir->i_mode & S_ISVTX))
 543                 return 0;
 544         if (inode->i_uid == fsuid)
 545                 return 0;
 546         if (dir->i_uid == fsuid)
 547                 return 0;
 548         return !capable(CAP_FOWNER);
 549 }
 550
 551 /*  copy of may_delete in fs/namei.c()
 552  *      Check whether we can remove a link victim from directory dir, check
 553  *  whether the type of victim is right.
 554  *  1. We can't do it if dir is read-only (done in permission())
 555  *  2. We should have write and exec permissions on dir
 556  *  3. We can't remove anything from append-only dir
 557  *  4. We can't do anything with immutable dir (done in permission())
 558  *  5. If the sticky bit on dir is set we should either
 559  *      a. be owner of dir, or
 560  *      b. be owner of victim, or
 561  *      c. have CAP_FOWNER capability
 562  *  6. If the victim is append-only or immutable we can't do antyhing with
 563  *     links pointing to it.
 564  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 565  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 566  *  9. We can't remove a root or mountpoint.
 567  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 568  *     nfs_async_unlink().
 569  */
 570
 571 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
 572 {
 573         int error;
 574
 575         if (!victim->d_inode)
 576                 return -ENOENT;
 577
 578         BUG_ON(victim->d_parent->d_inode != dir);
 579         audit_inode_child(victim, dir);
 580
 581         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 582         if (error)
 583                 return error;
 584         if (IS_APPEND(dir))
 585                 return -EPERM;
 586         if (btrfs_check_sticky(dir, victim->d_inode)||
 587                 IS_APPEND(victim->d_inode)||
 588             IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 589                 return -EPERM;
 590         if (isdir) {
 591                 if (!S_ISDIR(victim->d_inode->i_mode))
 592                         return -ENOTDIR;
 593                 if (IS_ROOT(victim))
 594                         return -EBUSY;
 595         } else if (S_ISDIR(victim->d_inode->i_mode))
 596                 return -EISDIR;
 597         if (IS_DEADDIR(dir))
 598                 return -ENOENT;
 599         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 600                 return -EBUSY;
 601         return 0;
 602 }
 603
 604 /* copy of may_create in fs/namei.c() */
 605 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 606 {
 607         if (child->d_inode)
 608                 return -EEXIST;
 609         if (IS_DEADDIR(dir))
 610                 return -ENOENT;
 611         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 612 }
 613
 614 /*
 615  * Create a new subvolume below @parent.  This is largely modeled after
 616  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 617  * inside this filesystem so it's quite a bit simpler.
 618  */
 619 static noinline int btrfs_mksubvol(struct path *parent,
 620                                    char *name, int namelen,
 621                                    struct btrfs_root *snap_src,
 622                                    u64 *async_transid, bool readonly)
 623 {
 624         struct inode *dir  = parent->dentry->d_inode;
 625         struct dentry *dentry;
 626         int error;
 627
 628         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
 629
 630         dentry = lookup_one_len(name, parent->dentry, namelen);
 631         error = PTR_ERR(dentry);
 632         if (IS_ERR(dentry))
 633                 goto out_unlock;
 634
 635         error = -EEXIST;
 636         if (dentry->d_inode)
 637                 goto out_dput;
 638
 639         error = mnt_want_write(parent->mnt);
 640         if (error)
 641                 goto out_dput;
 642
 643         error = btrfs_may_create(dir, dentry);
 644         if (error)
 645                 goto out_drop_write;
 646
 647         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 648
 649         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 650                 goto out_up_read;
 651
 652         if (snap_src) {
 653                 error = create_snapshot(snap_src, dentry,
 654                                         name, namelen, async_transid, readonly);
 655         } else {
 656                 error = create_subvol(BTRFS_I(dir)->root, dentry,
 657                                       name, namelen, async_transid);
 658         }
 659         if (!error)
 660                 fsnotify_mkdir(dir, dentry);
 661 out_up_read:
 662         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 663 out_drop_write:
 664         mnt_drop_write(parent->mnt);
 665 out_dput:
 666         dput(dentry);
 667 out_unlock:
 668         mutex_unlock(&dir->i_mutex);
 669         return error;
 670 }
 671
 672 /*
 673  * When we're defragging a range, we don't want to kick it off again
 674  * if it is really just waiting for delalloc to send it down.
 675  * If we find a nice big extent or delalloc range for the bytes in the
 676  * file you want to defrag, we return 0 to let you know to skip this
 677  * part of the file
 678  */
 679 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
 680 {
 681         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 682         struct extent_map *em = NULL;
 683         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 684         u64 end;
 685
 686         read_lock(&em_tree->lock);
 687         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 688         read_unlock(&em_tree->lock);
 689
 690         if (em) {
 691                 end = extent_map_end(em);
 692                 free_extent_map(em);
 693                 if (end - offset > thresh)
 694                         return 0;
 695         }
 696         /* if we already have a nice delalloc here, just stop */
 697         thresh /= 2;
 698         end = count_range_bits(io_tree, &offset, offset + thresh,
 699                                thresh, EXTENT_DELALLOC, 1);
 700         if (end >= thresh)
 701                 return 0;
 702         return 1;
 703 }
 704
 705 /*
 706  * helper function to walk through a file and find extents
 707  * newer than a specific transid, and smaller than thresh.
 708  *
 709  * This is used by the defragging code to find new and small
 710  * extents
 711  */
 712 static int find_new_extents(struct btrfs_root *root,
 713                             struct inode *inode, u64 newer_than,
 714                             u64 *off, int thresh)
 715 {
 716         struct btrfs_path *path;
 717         struct btrfs_key min_key;
 718         struct btrfs_key max_key;
 719         struct extent_buffer *leaf;
 720         struct btrfs_file_extent_item *extent;
 721         int type;
 722         int ret;
 723         u64 ino = btrfs_ino(inode);
 724
 725         path = btrfs_alloc_path();
 726         if (!path)
 727                 return -ENOMEM;
 728
 729         min_key.objectid = ino;
 730         min_key.type = BTRFS_EXTENT_DATA_KEY;
 731         min_key.offset = *off;
 732
 733         max_key.objectid = ino;
 734         max_key.type = (u8)-1;
 735         max_key.offset = (u64)-1;
 736
 737         path->keep_locks = 1;
 738
 739         while(1) {
 740                 ret = btrfs_search_forward(root, &min_key, &max_key,
 741                                            path, 0, newer_than);
 742                 if (ret != 0)
 743                         goto none;
 744                 if (min_key.objectid != ino)
 745                         goto none;
 746                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 747                         goto none;
 748
 749                 leaf = path->nodes[0];
 750                 extent = btrfs_item_ptr(leaf, path->slots[0],
 751                                         struct btrfs_file_extent_item);
 752
 753                 type = btrfs_file_extent_type(leaf, extent);
 754                 if (type == BTRFS_FILE_EXTENT_REG &&
 755                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 756                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 757                         *off = min_key.offset;
 758                         btrfs_free_path(path);
 759                         return 0;
 760                 }
 761
 762                 if (min_key.offset == (u64)-1)
 763                         goto none;
 764
 765                 min_key.offset++;
 766                 btrfs_release_path(path);
 767         }
 768 none:
 769         btrfs_free_path(path);
 770         return -ENOENT;
 771 }
 772
 773 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
 774                                int thresh, u64 *last_len, u64 *skip,
 775                                u64 *defrag_end)
 776 {
 777         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 778         struct extent_map *em = NULL;
 779         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 780         int ret = 1;
 781
 782         /*
 783          * make sure that once we start defragging an extent, we keep on
 784          * defragging it
 785          */
 786         if (start < *defrag_end)
 787                 return 1;
 788
 789         *skip = 0;
 790
 791         /*
 792          * hopefully we have this extent in the tree already, try without
 793          * the full extent lock
 794          */
 795         read_lock(&em_tree->lock);
 796         em = lookup_extent_mapping(em_tree, start, len);
 797         read_unlock(&em_tree->lock);
 798
 799         if (!em) {
 800                 /* get the big lock and read metadata off disk */
 801                 lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
 802                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 803                 unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);
 804
 805                 if (IS_ERR(em))
 806                         return 0;
 807         }
 808
 809         /* this will cover holes, and inline extents */
 810         if (em->block_start >= EXTENT_MAP_LAST_BYTE)
 811                 ret = 0;
 812
 813         /*
 814          * we hit a real extent, if it is big don't bother defragging it again
 815          */
 816         if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
 817                 ret = 0;
 818
 819         /*
 820          * last_len ends up being a counter of how many bytes we've defragged.
 821          * every time we choose not to defrag an extent, we reset *last_len
 822          * so that the next tiny extent will force a defrag.
 823          *
 824          * The end result of this is that tiny extents before a single big
 825          * extent will force at least part of that big extent to be defragged.
 826          */
 827         if (ret) {
 828                 *defrag_end = extent_map_end(em);
 829         } else {
 830                 *last_len = 0;
 831                 *skip = extent_map_end(em);
 832                 *defrag_end = 0;
 833         }
 834
 835         free_extent_map(em);
 836         return ret;
 837 }
 838
 839 /*
 840  * it doesn't do much good to defrag one or two pages
 841  * at a time.  This pulls in a nice chunk of pages
 842  * to COW and defrag.
 843  *
 844  * It also makes sure the delalloc code has enough
 845  * dirty data to avoid making new small extents as part
 846  * of the defrag
 847  *
 848  * It's a good idea to start RA on this range
 849  * before calling this.
 850  */
 851 static int cluster_pages_for_defrag(struct inode *inode,
 852                                     struct page **pages,
 853                                     unsigned long start_index,
 854                                     int num_pages)
 855 {
 856         unsigned long file_end;
 857         u64 isize = i_size_read(inode);
 858         u64 page_start;
 859         u64 page_end;
 860         int ret;
 861         int i;
 862         int i_done;
 863         struct btrfs_ordered_extent *ordered;
 864         struct extent_state *cached_state = NULL;
 865         struct extent_io_tree *tree;
 866         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
 867
 868         if (isize == 0)
 869                 return 0;
 870         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
 871
 872         ret = btrfs_delalloc_reserve_space(inode,
 873                                            num_pages << PAGE_CACHE_SHIFT);
 874         if (ret)
 875                 return ret;
 876         i_done = 0;
 877         tree = &BTRFS_I(inode)->io_tree;
 878
 879         /* step one, lock all the pages */
 880         for (i = 0; i < num_pages; i++) {
 881                 struct page *page;
 882 again:
 883                 page = find_or_create_page(inode->i_mapping,
 884                                            start_index + i, mask);
 885                 if (!page)
 886                         break;
 887
 888                 page_start = page_offset(page);
 889                 page_end = page_start + PAGE_CACHE_SIZE - 1;
 890                 while (1) {
 891                         lock_extent(tree, page_start, page_end, GFP_NOFS);
 892                         ordered = btrfs_lookup_ordered_extent(inode,
 893                                                               page_start);
 894                         unlock_extent(tree, page_start, page_end, GFP_NOFS);
 895                         if (!ordered)
 896                                 break;
 897
 898                         unlock_page(page);
 899                         btrfs_start_ordered_extent(inode, ordered, 1);
 900                         btrfs_put_ordered_extent(ordered);
 901                         lock_page(page);
 902                 }
 903
 904                 if (!PageUptodate(page)) {
 905                         btrfs_readpage(NULL, page);
 906                         lock_page(page);
 907                         if (!PageUptodate(page)) {
 908                                 unlock_page(page);
 909                                 page_cache_release(page);
 910                                 ret = -EIO;
 911                                 break;
 912                         }
 913                 }
 914
 915                 isize = i_size_read(inode);
 916                 file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
 917                 if (!isize || page->index > file_end) {
 918                         /* whoops, we blew past eof, skip this page */
 919                         unlock_page(page);
 920                         page_cache_release(page);
 921                         break;
 922                 }
 923
 924                 if (page->mapping != inode->i_mapping) {
 925                         unlock_page(page);
 926                         page_cache_release(page);
 927                         goto again;
 928                 }
 929
 930                 pages[i] = page;
 931                 i_done++;
 932         }
 933         if (!i_done || ret)
 934                 goto out;
 935
 936         if (!(inode->i_sb->s_flags & MS_ACTIVE))
 937                 goto out;
 938
 939         /*
 940          * so now we have a nice long stream of locked
 941          * and up to date pages, lets wait on them
 942          */
 943         for (i = 0; i < i_done; i++)
 944                 wait_on_page_writeback(pages[i]);
 945
 946         page_start = page_offset(pages[0]);
 947         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
 948
 949         lock_extent_bits(&BTRFS_I(inode)->io_tree,
 950                          page_start, page_end - 1, 0, &cached_state,
 951                          GFP_NOFS);
 952         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
 953                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
 954                           EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
 955                           GFP_NOFS);
 956
 957         if (i_done != num_pages) {
 958                 spin_lock(&BTRFS_I(inode)->lock);
 959                 BTRFS_I(inode)->outstanding_extents++;
 960                 spin_unlock(&BTRFS_I(inode)->lock);
 961                 btrfs_delalloc_release_space(inode,
 962                                      (num_pages - i_done) << PAGE_CACHE_SHIFT);
 963         }
 964
 965
 966         btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
 967                                   &cached_state);
 968
 969         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
 970                              page_start, page_end - 1, &cached_state,
 971                              GFP_NOFS);
 972
 973         for (i = 0; i < i_done; i++) {
 974                 clear_page_dirty_for_io(pages[i]);
 975                 ClearPageChecked(pages[i]);
 976                 set_page_extent_mapped(pages[i]);
 977                 set_page_dirty(pages[i]);
 978                 unlock_page(pages[i]);
 979                 page_cache_release(pages[i]);
 980         }
 981         return i_done;
 982 out:
 983         for (i = 0; i < i_done; i++) {
 984                 unlock_page(pages[i]);
 985                 page_cache_release(pages[i]);
 986         }
 987         btrfs_delalloc_release_space(inode, num_pages << PAGE_CACHE_SHIFT);
 988         return ret;
 989
 990 }
 991
 992 int btrfs_defrag_file(struct inode *inode, struct file *file,
 993                       struct btrfs_ioctl_defrag_range_args *range,
 994                       u64 newer_than, unsigned long max_to_defrag)
 995 {
 996         struct btrfs_root *root = BTRFS_I(inode)->root;
 997         struct btrfs_super_block *disk_super;
 998         struct file_ra_state *ra = NULL;
 999         unsigned long last_index;
1000         u64 isize = i_size_read(inode);
1001         u64 features;
1002         u64 last_len = 0;
1003         u64 skip = 0;
1004         u64 defrag_end = 0;
1005         u64 newer_off = range->start;
1006         unsigned long i;
1007         unsigned long ra_index = 0;
1008         int ret;
1009         int defrag_count = 0;
1010         int compress_type = BTRFS_COMPRESS_ZLIB;
1011         int extent_thresh = range->extent_thresh;
1012         int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1013         int cluster = max_cluster;
1014         u64 new_align = ~((u64)128 * 1024 - 1);
1015         struct page **pages = NULL;
1016
1017         if (extent_thresh == 0)
1018                 extent_thresh = 256 * 1024;
1019
1020         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1021                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1022                         return -EINVAL;
1023                 if (range->compress_type)
1024                         compress_type = range->compress_type;
1025         }
1026
1027         if (isize == 0)
1028                 return 0;
1029
1030         /*
1031          * if we were not given a file, allocate a readahead
1032          * context
1033          */
1034         if (!file) {
1035                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1036                 if (!ra)
1037                         return -ENOMEM;
1038                 file_ra_state_init(ra, inode->i_mapping);
1039         } else {
1040                 ra = &file->f_ra;
1041         }
1042
1043         pages = kmalloc(sizeof(struct page *) * max_cluster,
1044                         GFP_NOFS);
1045         if (!pages) {
1046                 ret = -ENOMEM;
1047                 goto out_ra;
1048         }
1049
1050         /* find the last page to defrag */
1051         if (range->start + range->len > range->start) {
1052                 last_index = min_t(u64, isize - 1,
1053                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1054         } else {
1055                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1056         }
1057
1058         if (newer_than) {
1059                 ret = find_new_extents(root, inode, newer_than,
1060                                        &newer_off, 64 * 1024);
1061                 if (!ret) {
1062                         range->start = newer_off;
1063                         /*
1064                          * we always align our defrag to help keep
1065                          * the extents in the file evenly spaced
1066                          */
1067                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1068                 } else
1069                         goto out_ra;
1070         } else {
1071                 i = range->start >> PAGE_CACHE_SHIFT;
1072         }
1073         if (!max_to_defrag)
1074                 max_to_defrag = last_index + 1;
1075
1076         /*
1077          * make writeback starts from i, so the defrag range can be
1078          * written sequentially.
1079          */
1080         if (i < inode->i_mapping->writeback_index)
1081                 inode->i_mapping->writeback_index = i;
1082
1083         while (i <= last_index && defrag_count < max_to_defrag &&
1084                (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1085                 PAGE_CACHE_SHIFT)) {
1086                 /*
1087                  * make sure we stop running if someone unmounts
1088                  * the FS
1089                  */
1090                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1091                         break;
1092
1093                 if (!newer_than &&
1094                     !should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1095                                         PAGE_CACHE_SIZE,
1096                                         extent_thresh,
1097                                         &last_len, &skip,
1098                                         &defrag_end)) {
1099                         unsigned long next;
1100                         /*
1101                          * the should_defrag function tells us how much to skip
1102                          * bump our counter by the suggested amount
1103                          */
1104                         next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1105                         i = max(i + 1, next);
1106                         continue;
1107                 }
1108
1109                 if (!newer_than) {
1110                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1111                                    PAGE_CACHE_SHIFT) - i;
1112                         cluster = min(cluster, max_cluster);
1113                 } else {
1114                         cluster = max_cluster;
1115                 }
1116
1117                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1118                         BTRFS_I(inode)->force_compress = compress_type;
1119
1120                 if (i + cluster > ra_index) {
1121                         ra_index = max(i, ra_index);
1122                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1123                                        cluster);
1124                         ra_index += max_cluster;
1125                 }
1126
1127                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1128                 if (ret < 0)
1129                         goto out_ra;
1130
1131                 defrag_count += ret;
1132                 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1133
1134                 if (newer_than) {
1135                         if (newer_off == (u64)-1)
1136                                 break;
1137
1138                         newer_off = max(newer_off + 1,
1139                                         (u64)i << PAGE_CACHE_SHIFT);
1140
1141                         ret = find_new_extents(root, inode,
1142                                                newer_than, &newer_off,
1143                                                64 * 1024);
1144                         if (!ret) {
1145                                 range->start = newer_off;
1146                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1147                         } else {
1148                                 break;
1149                         }
1150                 } else {
1151                         if (ret > 0) {
1152                                 i += ret;
1153                                 last_len += ret << PAGE_CACHE_SHIFT;
1154                         } else {
1155                                 i++;
1156                                 last_len = 0;
1157                         }
1158                 }
1159         }
1160
1161         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1162                 filemap_flush(inode->i_mapping);
1163
1164         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1165                 /* the filemap_flush will queue IO into the worker threads, but
1166                  * we have to make sure the IO is actually started and that
1167                  * ordered extents get created before we return
1168                  */
1169                 atomic_inc(&root->fs_info->async_submit_draining);
1170                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1171                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1172                         wait_event(root->fs_info->async_submit_wait,
1173                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1174                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1175                 }
1176                 atomic_dec(&root->fs_info->async_submit_draining);
1177
1178                 mutex_lock(&inode->i_mutex);
1179                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1180                 mutex_unlock(&inode->i_mutex);
1181         }
1182
1183         disk_super = root->fs_info->super_copy;
1184         features = btrfs_super_incompat_flags(disk_super);
1185         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1186                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1187                 btrfs_set_super_incompat_flags(disk_super, features);
1188         }
1189
1190         ret = defrag_count;
1191
1192 out_ra:
1193         if (!file)
1194                 kfree(ra);
1195         kfree(pages);
1196         return ret;
1197 }
1198
1199 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1200                                         void __user *arg)
1201 {
1202         u64 new_size;
1203         u64 old_size;
1204         u64 devid = 1;
1205         struct btrfs_ioctl_vol_args *vol_args;
1206         struct btrfs_trans_handle *trans;
1207         struct btrfs_device *device = NULL;
1208         char *sizestr;
1209         char *devstr = NULL;
1210         int ret = 0;
1211         int mod = 0;
1212
1213         if (root->fs_info->sb->s_flags & MS_RDONLY)
1214                 return -EROFS;
1215
1216         if (!capable(CAP_SYS_ADMIN))
1217                 return -EPERM;
1218
1219         mutex_lock(&root->fs_info->volume_mutex);
1220         if (root->fs_info->balance_ctl) {
1221                 printk(KERN_INFO "btrfs: balance in progress\n");
1222                 ret = -EINVAL;
1223                 goto out;
1224         }
1225
1226         vol_args = memdup_user(arg, sizeof(*vol_args));
1227         if (IS_ERR(vol_args)) {
1228                 ret = PTR_ERR(vol_args);
1229                 goto out;
1230         }
1231
1232         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1233
1234         sizestr = vol_args->name;
1235         devstr = strchr(sizestr, ':');
1236         if (devstr) {
1237                 char *end;
1238                 sizestr = devstr + 1;
1239                 *devstr = '\0';
1240                 devstr = vol_args->name;
1241                 devid = simple_strtoull(devstr, &end, 10);
1242                 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1243                        (unsigned long long)devid);
1244         }
1245         device = btrfs_find_device(root, devid, NULL, NULL);
1246         if (!device) {
1247                 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1248                        (unsigned long long)devid);
1249                 ret = -EINVAL;
1250                 goto out_free;
1251         }
1252         if (!strcmp(sizestr, "max"))
1253                 new_size = device->bdev->bd_inode->i_size;
1254         else {
1255                 if (sizestr[0] == '-') {
1256                         mod = -1;
1257                         sizestr++;
1258                 } else if (sizestr[0] == '+') {
1259                         mod = 1;
1260                         sizestr++;
1261                 }
1262                 new_size = memparse(sizestr, NULL);
1263                 if (new_size == 0) {
1264                         ret = -EINVAL;
1265                         goto out_free;
1266                 }
1267         }
1268
1269         old_size = device->total_bytes;
1270
1271         if (mod < 0) {
1272                 if (new_size > old_size) {
1273                         ret = -EINVAL;
1274                         goto out_free;
1275                 }
1276                 new_size = old_size - new_size;
1277         } else if (mod > 0) {
1278                 new_size = old_size + new_size;
1279         }
1280
1281         if (new_size < 256 * 1024 * 1024) {
1282                 ret = -EINVAL;
1283                 goto out_free;
1284         }
1285         if (new_size > device->bdev->bd_inode->i_size) {
1286                 ret = -EFBIG;
1287                 goto out_free;
1288         }
1289
1290         do_div(new_size, root->sectorsize);
1291         new_size *= root->sectorsize;
1292
1293         printk(KERN_INFO "btrfs: new size for %s is %llu\n",
1294                 device->name, (unsigned long long)new_size);
1295
1296         if (new_size > old_size) {
1297                 trans = btrfs_start_transaction(root, 0);
1298                 if (IS_ERR(trans)) {
1299                         ret = PTR_ERR(trans);
1300                         goto out_free;
1301                 }
1302                 ret = btrfs_grow_device(trans, device, new_size);
1303                 btrfs_commit_transaction(trans, root);
1304         } else if (new_size < old_size) {
1305                 ret = btrfs_shrink_device(device, new_size);
1306         }
1307
1308 out_free:
1309         kfree(vol_args);
1310 out:
1311         mutex_unlock(&root->fs_info->volume_mutex);
1312         return ret;
1313 }
1314
1315 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1316                                                     char *name,
1317                                                     unsigned long fd,
1318                                                     int subvol,
1319                                                     u64 *transid,
1320                                                     bool readonly)
1321 {
1322         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1323         struct file *src_file;
1324         int namelen;
1325         int ret = 0;
1326
1327         if (root->fs_info->sb->s_flags & MS_RDONLY)
1328                 return -EROFS;
1329
1330         namelen = strlen(name);
1331         if (strchr(name, '/')) {
1332                 ret = -EINVAL;
1333                 goto out;
1334         }
1335
1336         if (name[0] == '.' &&
1337            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1338                 ret = -EEXIST;
1339                 goto out;
1340         }
1341
1342         if (subvol) {
1343                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1344                                      NULL, transid, readonly);
1345         } else {
1346                 struct inode *src_inode;
1347                 src_file = fget(fd);
1348                 if (!src_file) {
1349                         ret = -EINVAL;
1350                         goto out;
1351                 }
1352
1353                 src_inode = src_file->f_path.dentry->d_inode;
1354                 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1355                         printk(KERN_INFO "btrfs: Snapshot src from "
1356                                "another FS\n");
1357                         ret = -EINVAL;
1358                         fput(src_file);
1359                         goto out;
1360                 }
1361                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1362                                      BTRFS_I(src_inode)->root,
1363                                      transid, readonly);
1364                 fput(src_file);
1365         }
1366 out:
1367         return ret;
1368 }
1369
1370 static noinline int btrfs_ioctl_snap_create(struct file *file,
1371                                             void __user *arg, int subvol)
1372 {
1373         struct btrfs_ioctl_vol_args *vol_args;
1374         int ret;
1375
1376         vol_args = memdup_user(arg, sizeof(*vol_args));
1377         if (IS_ERR(vol_args))
1378                 return PTR_ERR(vol_args);
1379         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1380
1381         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1382                                               vol_args->fd, subvol,
1383                                               NULL, false);
1384
1385         kfree(vol_args);
1386         return ret;
1387 }
1388
1389 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1390                                                void __user *arg, int subvol)
1391 {
1392         struct btrfs_ioctl_vol_args_v2 *vol_args;
1393         int ret;
1394         u64 transid = 0;
1395         u64 *ptr = NULL;
1396         bool readonly = false;
1397
1398         vol_args = memdup_user(arg, sizeof(*vol_args));
1399         if (IS_ERR(vol_args))
1400                 return PTR_ERR(vol_args);
1401         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1402
1403         if (vol_args->flags &
1404             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1405                 ret = -EOPNOTSUPP;
1406                 goto out;
1407         }
1408
1409         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1410                 ptr = &transid;
1411         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1412                 readonly = true;
1413
1414         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1415                                               vol_args->fd, subvol,
1416                                               ptr, readonly);
1417
1418         if (ret == 0 && ptr &&
1419             copy_to_user(arg +
1420                          offsetof(struct btrfs_ioctl_vol_args_v2,
1421                                   transid), ptr, sizeof(*ptr)))
1422                 ret = -EFAULT;
1423 out:
1424         kfree(vol_args);
1425         return ret;
1426 }
1427
1428 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1429                                                 void __user *arg)
1430 {
1431         struct inode *inode = fdentry(file)->d_inode;
1432         struct btrfs_root *root = BTRFS_I(inode)->root;
1433         int ret = 0;
1434         u64 flags = 0;
1435
1436         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1437                 return -EINVAL;
1438
1439         down_read(&root->fs_info->subvol_sem);
1440         if (btrfs_root_readonly(root))
1441                 flags |= BTRFS_SUBVOL_RDONLY;
1442         up_read(&root->fs_info->subvol_sem);
1443
1444         if (copy_to_user(arg, &flags, sizeof(flags)))
1445                 ret = -EFAULT;
1446
1447         return ret;
1448 }
1449
1450 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1451                                               void __user *arg)
1452 {
1453         struct inode *inode = fdentry(file)->d_inode;
1454         struct btrfs_root *root = BTRFS_I(inode)->root;
1455         struct btrfs_trans_handle *trans;
1456         u64 root_flags;
1457         u64 flags;
1458         int ret = 0;
1459
1460         if (root->fs_info->sb->s_flags & MS_RDONLY)
1461                 return -EROFS;
1462
1463         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1464                 return -EINVAL;
1465
1466         if (copy_from_user(&flags, arg, sizeof(flags)))
1467                 return -EFAULT;
1468
1469         if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1470                 return -EINVAL;
1471
1472         if (flags & ~BTRFS_SUBVOL_RDONLY)
1473                 return -EOPNOTSUPP;
1474
1475         if (!inode_owner_or_capable(inode))
1476                 return -EACCES;
1477
1478         down_write(&root->fs_info->subvol_sem);
1479
1480         /* nothing to do */
1481         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1482                 goto out;
1483
1484         root_flags = btrfs_root_flags(&root->root_item);
1485         if (flags & BTRFS_SUBVOL_RDONLY)
1486                 btrfs_set_root_flags(&root->root_item,
1487                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1488         else
1489                 btrfs_set_root_flags(&root->root_item,
1490                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1491
1492         trans = btrfs_start_transaction(root, 1);
1493         if (IS_ERR(trans)) {
1494                 ret = PTR_ERR(trans);
1495                 goto out_reset;
1496         }
1497
1498         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1499                                 &root->root_key, &root->root_item);
1500
1501         btrfs_commit_transaction(trans, root);
1502 out_reset:
1503         if (ret)
1504                 btrfs_set_root_flags(&root->root_item, root_flags);
1505 out:
1506         up_write(&root->fs_info->subvol_sem);
1507         return ret;
1508 }
1509
1510 /*
1511  * helper to check if the subvolume references other subvolumes
1512  */
1513 static noinline int may_destroy_subvol(struct btrfs_root *root)
1514 {
1515         struct btrfs_path *path;
1516         struct btrfs_key key;
1517         int ret;
1518
1519         path = btrfs_alloc_path();
1520         if (!path)
1521                 return -ENOMEM;
1522
1523         key.objectid = root->root_key.objectid;
1524         key.type = BTRFS_ROOT_REF_KEY;
1525         key.offset = (u64)-1;
1526
1527         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1528                                 &key, path, 0, 0);
1529         if (ret < 0)
1530                 goto out;
1531         BUG_ON(ret == 0);
1532
1533         ret = 0;
1534         if (path->slots[0] > 0) {
1535                 path->slots[0]--;
1536                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1537                 if (key.objectid == root->root_key.objectid &&
1538                     key.type == BTRFS_ROOT_REF_KEY)
1539                         ret = -ENOTEMPTY;
1540         }
1541 out:
1542         btrfs_free_path(path);
1543         return ret;
1544 }
1545
1546 static noinline int key_in_sk(struct btrfs_key *key,
1547                               struct btrfs_ioctl_search_key *sk)
1548 {
1549         struct btrfs_key test;
1550         int ret;
1551
1552         test.objectid = sk->min_objectid;
1553         test.type = sk->min_type;
1554         test.offset = sk->min_offset;
1555
1556         ret = btrfs_comp_cpu_keys(key, &test);
1557         if (ret < 0)
1558                 return 0;
1559
1560         test.objectid = sk->max_objectid;
1561         test.type = sk->max_type;
1562         test.offset = sk->max_offset;
1563
1564         ret = btrfs_comp_cpu_keys(key, &test);
1565         if (ret > 0)
1566                 return 0;
1567         return 1;
1568 }
1569
1570 static noinline int copy_to_sk(struct btrfs_root *root,
1571                                struct btrfs_path *path,
1572                                struct btrfs_key *key,
1573                                struct btrfs_ioctl_search_key *sk,
1574                                char *buf,
1575                                unsigned long *sk_offset,
1576                                int *num_found)
1577 {
1578         u64 found_transid;
1579         struct extent_buffer *leaf;
1580         struct btrfs_ioctl_search_header sh;
1581         unsigned long item_off;
1582         unsigned long item_len;
1583         int nritems;
1584         int i;
1585         int slot;
1586         int ret = 0;
1587
1588         leaf = path->nodes[0];
1589         slot = path->slots[0];
1590         nritems = btrfs_header_nritems(leaf);
1591
1592         if (btrfs_header_generation(leaf) > sk->max_transid) {
1593                 i = nritems;
1594                 goto advance_key;
1595         }
1596         found_transid = btrfs_header_generation(leaf);
1597
1598         for (i = slot; i < nritems; i++) {
1599                 item_off = btrfs_item_ptr_offset(leaf, i);
1600                 item_len = btrfs_item_size_nr(leaf, i);
1601
1602                 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1603                         item_len = 0;
1604
1605                 if (sizeof(sh) + item_len + *sk_offset >
1606                     BTRFS_SEARCH_ARGS_BUFSIZE) {
1607                         ret = 1;
1608                         goto overflow;
1609                 }
1610
1611                 btrfs_item_key_to_cpu(leaf, key, i);
1612                 if (!key_in_sk(key, sk))
1613                         continue;
1614
1615                 sh.objectid = key->objectid;
1616                 sh.offset = key->offset;
1617                 sh.type = key->type;
1618                 sh.len = item_len;
1619                 sh.transid = found_transid;
1620
1621                 /* copy search result header */
1622                 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1623                 *sk_offset += sizeof(sh);
1624
1625                 if (item_len) {
1626                         char *p = buf + *sk_offset;
1627                         /* copy the item */
1628                         read_extent_buffer(leaf, p,
1629                                            item_off, item_len);
1630                         *sk_offset += item_len;
1631                 }
1632                 (*num_found)++;
1633
1634                 if (*num_found >= sk->nr_items)
1635                         break;
1636         }
1637 advance_key:
1638         ret = 0;
1639         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1640                 key->offset++;
1641         else if (key->type < (u8)-1 && key->type < sk->max_type) {
1642                 key->offset = 0;
1643                 key->type++;
1644         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1645                 key->offset = 0;
1646                 key->type = 0;
1647                 key->objectid++;
1648         } else
1649                 ret = 1;
1650 overflow:
1651         return ret;
1652 }
1653
1654 static noinline int search_ioctl(struct inode *inode,
1655                                  struct btrfs_ioctl_search_args *args)
1656 {
1657         struct btrfs_root *root;
1658         struct btrfs_key key;
1659         struct btrfs_key max_key;
1660         struct btrfs_path *path;
1661         struct btrfs_ioctl_search_key *sk = &args->key;
1662         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1663         int ret;
1664         int num_found = 0;
1665         unsigned long sk_offset = 0;
1666
1667         path = btrfs_alloc_path();
1668         if (!path)
1669                 return -ENOMEM;
1670
1671         if (sk->tree_id == 0) {
1672                 /* search the root of the inode that was passed */
1673                 root = BTRFS_I(inode)->root;
1674         } else {
1675                 key.objectid = sk->tree_id;
1676                 key.type = BTRFS_ROOT_ITEM_KEY;
1677                 key.offset = (u64)-1;
1678                 root = btrfs_read_fs_root_no_name(info, &key);
1679                 if (IS_ERR(root)) {
1680                         printk(KERN_ERR "could not find root %llu\n",
1681                                sk->tree_id);
1682                         btrfs_free_path(path);
1683                         return -ENOENT;
1684                 }
1685         }
1686
1687         key.objectid = sk->min_objectid;
1688         key.type = sk->min_type;
1689         key.offset = sk->min_offset;
1690
1691         max_key.objectid = sk->max_objectid;
1692         max_key.type = sk->max_type;
1693         max_key.offset = sk->max_offset;
1694
1695         path->keep_locks = 1;
1696
1697         while(1) {
1698                 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1699                                            sk->min_transid);
1700                 if (ret != 0) {
1701                         if (ret > 0)
1702                                 ret = 0;
1703                         goto err;
1704                 }
1705                 ret = copy_to_sk(root, path, &key, sk, args->buf,
1706                                  &sk_offset, &num_found);
1707                 btrfs_release_path(path);
1708                 if (ret || num_found >= sk->nr_items)
1709                         break;
1710
1711         }
1712         ret = 0;
1713 err:
1714         sk->nr_items = num_found;
1715         btrfs_free_path(path);
1716         return ret;
1717 }
1718
1719 static noinline int btrfs_ioctl_tree_search(struct file *file,
1720                                            void __user *argp)
1721 {
1722          struct btrfs_ioctl_search_args *args;
1723          struct inode *inode;
1724          int ret;
1725
1726         if (!capable(CAP_SYS_ADMIN))
1727                 return -EPERM;
1728
1729         args = memdup_user(argp, sizeof(*args));
1730         if (IS_ERR(args))
1731                 return PTR_ERR(args);
1732
1733         inode = fdentry(file)->d_inode;
1734         ret = search_ioctl(inode, args);
1735         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1736                 ret = -EFAULT;
1737         kfree(args);
1738         return ret;
1739 }
1740
1741 /*
1742  * Search INODE_REFs to identify path name of 'dirid' directory
1743  * in a 'tree_id' tree. and sets path name to 'name'.
1744  */
1745 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1746                                 u64 tree_id, u64 dirid, char *name)
1747 {
1748         struct btrfs_root *root;
1749         struct btrfs_key key;
1750         char *ptr;
1751         int ret = -1;
1752         int slot;
1753         int len;
1754         int total_len = 0;
1755         struct btrfs_inode_ref *iref;
1756         struct extent_buffer *l;
1757         struct btrfs_path *path;
1758
1759         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1760                 name[0]='\0';
1761                 return 0;
1762         }
1763
1764         path = btrfs_alloc_path();
1765         if (!path)
1766                 return -ENOMEM;
1767
1768         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1769
1770         key.objectid = tree_id;
1771         key.type = BTRFS_ROOT_ITEM_KEY;
1772         key.offset = (u64)-1;
1773         root = btrfs_read_fs_root_no_name(info, &key);
1774         if (IS_ERR(root)) {
1775                 printk(KERN_ERR "could not find root %llu\n", tree_id);
1776                 ret = -ENOENT;
1777                 goto out;
1778         }
1779
1780         key.objectid = dirid;
1781         key.type = BTRFS_INODE_REF_KEY;
1782         key.offset = (u64)-1;
1783
1784         while(1) {
1785                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1786                 if (ret < 0)
1787                         goto out;
1788
1789                 l = path->nodes[0];
1790                 slot = path->slots[0];
1791                 if (ret > 0 && slot > 0)
1792                         slot--;
1793                 btrfs_item_key_to_cpu(l, &key, slot);
1794
1795                 if (ret > 0 && (key.objectid != dirid ||
1796                                 key.type != BTRFS_INODE_REF_KEY)) {
1797                         ret = -ENOENT;
1798                         goto out;
1799                 }
1800
1801                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1802                 len = btrfs_inode_ref_name_len(l, iref);
1803                 ptr -= len + 1;
1804                 total_len += len + 1;
1805                 if (ptr < name)
1806                         goto out;
1807
1808                 *(ptr + len) = '/';
1809                 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1810
1811                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1812                         break;
1813
1814                 btrfs_release_path(path);
1815                 key.objectid = key.offset;
1816                 key.offset = (u64)-1;
1817                 dirid = key.objectid;
1818         }
1819         if (ptr < name)
1820                 goto out;
1821         memmove(name, ptr, total_len);
1822         name[total_len]='\0';
1823         ret = 0;
1824 out:
1825         btrfs_free_path(path);
1826         return ret;
1827 }
1828
1829 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1830                                            void __user *argp)
1831 {
1832          struct btrfs_ioctl_ino_lookup_args *args;
1833          struct inode *inode;
1834          int ret;
1835
1836         if (!capable(CAP_SYS_ADMIN))
1837                 return -EPERM;
1838
1839         args = memdup_user(argp, sizeof(*args));
1840         if (IS_ERR(args))
1841                 return PTR_ERR(args);
1842
1843         inode = fdentry(file)->d_inode;
1844
1845         if (args->treeid == 0)
1846                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1847
1848         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1849                                         args->treeid, args->objectid,
1850                                         args->name);
1851
1852         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1853                 ret = -EFAULT;
1854
1855         kfree(args);
1856         return ret;
1857 }
1858
1859 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1860                                              void __user *arg)
1861 {
1862         struct dentry *parent = fdentry(file);
1863         struct dentry *dentry;
1864         struct inode *dir = parent->d_inode;
1865         struct inode *inode;
1866         struct btrfs_root *root = BTRFS_I(dir)->root;
1867         struct btrfs_root *dest = NULL;
1868         struct btrfs_ioctl_vol_args *vol_args;
1869         struct btrfs_trans_handle *trans;
1870         int namelen;
1871         int ret;
1872         int err = 0;
1873
1874         vol_args = memdup_user(arg, sizeof(*vol_args));
1875         if (IS_ERR(vol_args))
1876                 return PTR_ERR(vol_args);
1877
1878         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1879         namelen = strlen(vol_args->name);
1880         if (strchr(vol_args->name, '/') ||
1881             strncmp(vol_args->name, "..", namelen) == 0) {
1882                 err = -EINVAL;
1883                 goto out;
1884         }
1885
1886         err = mnt_want_write(file->f_path.mnt);
1887         if (err)
1888                 goto out;
1889
1890         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1891         dentry = lookup_one_len(vol_args->name, parent, namelen);
1892         if (IS_ERR(dentry)) {
1893                 err = PTR_ERR(dentry);
1894                 goto out_unlock_dir;
1895         }
1896
1897         if (!dentry->d_inode) {
1898                 err = -ENOENT;
1899                 goto out_dput;
1900         }
1901
1902         inode = dentry->d_inode;
1903         dest = BTRFS_I(inode)->root;
1904         if (!capable(CAP_SYS_ADMIN)){
1905                 /*
1906                  * Regular user.  Only allow this with a special mount
1907                  * option, when the user has write+exec access to the
1908                  * subvol root, and when rmdir(2) would have been
1909                  * allowed.
1910                  *
1911                  * Note that this is _not_ check that the subvol is
1912                  * empty or doesn't contain data that we wouldn't
1913                  * otherwise be able to delete.
1914                  *
1915                  * Users who want to delete empty subvols should try
1916                  * rmdir(2).
1917                  */
1918                 err = -EPERM;
1919                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1920                         goto out_dput;
1921
1922                 /*
1923                  * Do not allow deletion if the parent dir is the same
1924                  * as the dir to be deleted.  That means the ioctl
1925                  * must be called on the dentry referencing the root
1926                  * of the subvol, not a random directory contained
1927                  * within it.
1928                  */
1929                 err = -EINVAL;
1930                 if (root == dest)
1931                         goto out_dput;
1932
1933                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1934                 if (err)
1935                         goto out_dput;
1936
1937                 /* check if subvolume may be deleted by a non-root user */
1938                 err = btrfs_may_delete(dir, dentry, 1);
1939                 if (err)
1940                         goto out_dput;
1941         }
1942
1943         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1944                 err = -EINVAL;
1945                 goto out_dput;
1946         }
1947
1948         mutex_lock(&inode->i_mutex);
1949         err = d_invalidate(dentry);
1950         if (err)
1951                 goto out_unlock;
1952
1953         down_write(&root->fs_info->subvol_sem);
1954
1955         err = may_destroy_subvol(dest);
1956         if (err)
1957                 goto out_up_write;
1958
1959         trans = btrfs_start_transaction(root, 0);
1960         if (IS_ERR(trans)) {
1961                 err = PTR_ERR(trans);
1962                 goto out_up_write;
1963         }
1964         trans->block_rsv = &root->fs_info->global_block_rsv;
1965
1966         ret = btrfs_unlink_subvol(trans, root, dir,
1967                                 dest->root_key.objectid,
1968                                 dentry->d_name.name,
1969                                 dentry->d_name.len);
1970         BUG_ON(ret);
1971
1972         btrfs_record_root_in_trans(trans, dest);
1973
1974         memset(&dest->root_item.drop_progress, 0,
1975                 sizeof(dest->root_item.drop_progress));
1976         dest->root_item.drop_level = 0;
1977         btrfs_set_root_refs(&dest->root_item, 0);
1978
1979         if (!xchg(&dest->orphan_item_inserted, 1)) {
1980                 ret = btrfs_insert_orphan_item(trans,
1981                                         root->fs_info->tree_root,
1982                                         dest->root_key.objectid);
1983                 BUG_ON(ret);
1984         }
1985
1986         ret = btrfs_end_transaction(trans, root);
1987         BUG_ON(ret);
1988         inode->i_flags |= S_DEAD;
1989 out_up_write:
1990         up_write(&root->fs_info->subvol_sem);
1991 out_unlock:
1992         mutex_unlock(&inode->i_mutex);
1993         if (!err) {
1994                 shrink_dcache_sb(root->fs_info->sb);
1995                 btrfs_invalidate_inodes(dest);
1996                 d_delete(dentry);
1997         }
1998 out_dput:
1999         dput(dentry);
2000 out_unlock_dir:
2001         mutex_unlock(&dir->i_mutex);
2002         mnt_drop_write(file->f_path.mnt);
2003 out:
2004         kfree(vol_args);
2005         return err;
2006 }
2007
2008 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2009 {
2010         struct inode *inode = fdentry(file)->d_inode;
2011         struct btrfs_root *root = BTRFS_I(inode)->root;
2012         struct btrfs_ioctl_defrag_range_args *range;
2013         int ret;
2014
2015         if (btrfs_root_readonly(root))
2016                 return -EROFS;
2017
2018         ret = mnt_want_write(file->f_path.mnt);
2019         if (ret)
2020                 return ret;
2021
2022         switch (inode->i_mode & S_IFMT) {
2023         case S_IFDIR:
2024                 if (!capable(CAP_SYS_ADMIN)) {
2025                         ret = -EPERM;
2026                         goto out;
2027                 }
2028                 ret = btrfs_defrag_root(root, 0);
2029                 if (ret)
2030                         goto out;
2031                 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
2032                 break;
2033         case S_IFREG:
2034                 if (!(file->f_mode & FMODE_WRITE)) {
2035                         ret = -EINVAL;
2036                         goto out;
2037                 }
2038
2039                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2040                 if (!range) {
2041                         ret = -ENOMEM;
2042                         goto out;
2043                 }
2044
2045                 if (argp) {
2046                         if (copy_from_user(range, argp,
2047                                            sizeof(*range))) {
2048                                 ret = -EFAULT;
2049                                 kfree(range);
2050                                 goto out;
2051                         }
2052                         /* compression requires us to start the IO */
2053                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2054                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2055                                 range->extent_thresh = (u32)-1;
2056                         }
2057                 } else {
2058                         /* the rest are all set to zero by kzalloc */
2059                         range->len = (u64)-1;
2060                 }
2061                 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2062                                         range, 0, 0);
2063                 if (ret > 0)
2064                         ret = 0;
2065                 kfree(range);
2066                 break;
2067         default:
2068                 ret = -EINVAL;
2069         }
2070 out:
2071         mnt_drop_write(file->f_path.mnt);
2072         return ret;
2073 }
2074
2075 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2076 {
2077         struct btrfs_ioctl_vol_args *vol_args;
2078         int ret;
2079
2080         if (!capable(CAP_SYS_ADMIN))
2081                 return -EPERM;
2082
2083         mutex_lock(&root->fs_info->volume_mutex);
2084         if (root->fs_info->balance_ctl) {
2085                 printk(KERN_INFO "btrfs: balance in progress\n");
2086                 ret = -EINVAL;
2087                 goto out;
2088         }
2089
2090         vol_args = memdup_user(arg, sizeof(*vol_args));
2091         if (IS_ERR(vol_args)) {
2092                 ret = PTR_ERR(vol_args);
2093                 goto out;
2094         }
2095
2096         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2097         ret = btrfs_init_new_device(root, vol_args->name);
2098
2099         kfree(vol_args);
2100 out:
2101         mutex_unlock(&root->fs_info->volume_mutex);
2102         return ret;
2103 }
2104
2105 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2106 {
2107         struct btrfs_ioctl_vol_args *vol_args;
2108         int ret;
2109
2110         if (!capable(CAP_SYS_ADMIN))
2111                 return -EPERM;
2112
2113         if (root->fs_info->sb->s_flags & MS_RDONLY)
2114                 return -EROFS;
2115
2116         mutex_lock(&root->fs_info->volume_mutex);
2117         if (root->fs_info->balance_ctl) {
2118                 printk(KERN_INFO "btrfs: balance in progress\n");
2119                 ret = -EINVAL;
2120                 goto out;
2121         }
2122
2123         vol_args = memdup_user(arg, sizeof(*vol_args));
2124         if (IS_ERR(vol_args)) {
2125                 ret = PTR_ERR(vol_args);
2126                 goto out;
2127         }
2128
2129         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2130         ret = btrfs_rm_device(root, vol_args->name);
2131
2132         kfree(vol_args);
2133 out:
2134         mutex_unlock(&root->fs_info->volume_mutex);
2135         return ret;
2136 }
2137
2138 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2139 {
2140         struct btrfs_ioctl_fs_info_args *fi_args;
2141         struct btrfs_device *device;
2142         struct btrfs_device *next;
2143         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2144         int ret = 0;
2145
2146         if (!capable(CAP_SYS_ADMIN))
2147                 return -EPERM;
2148
2149         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2150         if (!fi_args)
2151                 return -ENOMEM;
2152
2153         fi_args->num_devices = fs_devices->num_devices;
2154         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2155
2156         mutex_lock(&fs_devices->device_list_mutex);
2157         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2158                 if (device->devid > fi_args->max_id)
2159                         fi_args->max_id = device->devid;
2160         }
2161         mutex_unlock(&fs_devices->device_list_mutex);
2162
2163         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2164                 ret = -EFAULT;
2165
2166         kfree(fi_args);
2167         return ret;
2168 }
2169
2170 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2171 {
2172         struct btrfs_ioctl_dev_info_args *di_args;
2173         struct btrfs_device *dev;
2174         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2175         int ret = 0;
2176         char *s_uuid = NULL;
2177         char empty_uuid[BTRFS_UUID_SIZE] = {0};
2178
2179         if (!capable(CAP_SYS_ADMIN))
2180                 return -EPERM;
2181
2182         di_args = memdup_user(arg, sizeof(*di_args));
2183         if (IS_ERR(di_args))
2184                 return PTR_ERR(di_args);
2185
2186         if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2187                 s_uuid = di_args->uuid;
2188
2189         mutex_lock(&fs_devices->device_list_mutex);
2190         dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2191         mutex_unlock(&fs_devices->device_list_mutex);
2192
2193         if (!dev) {
2194                 ret = -ENODEV;
2195                 goto out;
2196         }
2197
2198         di_args->devid = dev->devid;
2199         di_args->bytes_used = dev->bytes_used;
2200         di_args->total_bytes = dev->total_bytes;
2201         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2202         strncpy(di_args->path, dev->name, sizeof(di_args->path));
2203
2204 out:
2205         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2206                 ret = -EFAULT;
2207
2208         kfree(di_args);
2209         return ret;
2210 }
2211
2212 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2213                                        u64 off, u64 olen, u64 destoff)
2214 {
2215         struct inode *inode = fdentry(file)->d_inode;
2216         struct btrfs_root *root = BTRFS_I(inode)->root;
2217         struct file *src_file;
2218         struct inode *src;
2219         struct btrfs_trans_handle *trans;
2220         struct btrfs_path *path;
2221         struct extent_buffer *leaf;
2222         char *buf;
2223         struct btrfs_key key;
2224         u32 nritems;
2225         int slot;
2226         int ret;
2227         u64 len = olen;
2228         u64 bs = root->fs_info->sb->s_blocksize;
2229         u64 hint_byte;
2230
2231         /*
2232          * TODO:
2233          * - split compressed inline extents.  annoying: we need to
2234          *   decompress into destination's address_space (the file offset
2235          *   may change, so source mapping won't do), then recompress (or
2236          *   otherwise reinsert) a subrange.
2237          * - allow ranges within the same file to be cloned (provided
2238          *   they don't overlap)?
2239          */
2240
2241         /* the destination must be opened for writing */
2242         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2243                 return -EINVAL;
2244
2245         if (btrfs_root_readonly(root))
2246                 return -EROFS;
2247
2248         ret = mnt_want_write(file->f_path.mnt);
2249         if (ret)
2250                 return ret;
2251
2252         src_file = fget(srcfd);
2253         if (!src_file) {
2254                 ret = -EBADF;
2255                 goto out_drop_write;
2256         }
2257
2258         src = src_file->f_dentry->d_inode;
2259
2260         ret = -EINVAL;
2261         if (src == inode)
2262                 goto out_fput;
2263
2264         /* the src must be open for reading */
2265         if (!(src_file->f_mode & FMODE_READ))
2266                 goto out_fput;
2267
2268         /* don't make the dst file partly checksummed */
2269         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2270             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2271                 goto out_fput;
2272
2273         ret = -EISDIR;
2274         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2275                 goto out_fput;
2276
2277         ret = -EXDEV;
2278         if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2279                 goto out_fput;
2280
2281         ret = -ENOMEM;
2282         buf = vmalloc(btrfs_level_size(root, 0));
2283         if (!buf)
2284                 goto out_fput;
2285
2286         path = btrfs_alloc_path();
2287         if (!path) {
2288                 vfree(buf);
2289                 goto out_fput;
2290         }
2291         path->reada = 2;
2292
2293         if (inode < src) {
2294                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2295                 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2296         } else {
2297                 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2298                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2299         }
2300
2301         /* determine range to clone */
2302         ret = -EINVAL;
2303         if (off + len > src->i_size || off + len < off)
2304                 goto out_unlock;
2305         if (len == 0)
2306                 olen = len = src->i_size - off;
2307         /* if we extend to eof, continue to block boundary */
2308         if (off + len == src->i_size)
2309                 len = ALIGN(src->i_size, bs) - off;
2310
2311         /* verify the end result is block aligned */
2312         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2313             !IS_ALIGNED(destoff, bs))
2314                 goto out_unlock;
2315
2316         if (destoff > inode->i_size) {
2317                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2318                 if (ret)
2319                         goto out_unlock;
2320         }
2321
2322         /* truncate page cache pages from target inode range */
2323         truncate_inode_pages_range(&inode->i_data, destoff,
2324                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
2325
2326         /* do any pending delalloc/csum calc on src, one way or
2327            another, and lock file content */
2328         while (1) {
2329                 struct btrfs_ordered_extent *ordered;
2330                 lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2331                 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2332                 if (!ordered &&
2333                     !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2334                                    EXTENT_DELALLOC, 0, NULL))
2335                         break;
2336                 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2337                 if (ordered)
2338                         btrfs_put_ordered_extent(ordered);
2339                 btrfs_wait_ordered_range(src, off, len);
2340         }
2341
2342         /* clone data */
2343         key.objectid = btrfs_ino(src);
2344         key.type = BTRFS_EXTENT_DATA_KEY;
2345         key.offset = 0;
2346
2347         while (1) {
2348                 /*
2349                  * note the key will change type as we walk through the
2350                  * tree.
2351                  */
2352                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2353                 if (ret < 0)
2354                         goto out;
2355
2356                 nritems = btrfs_header_nritems(path->nodes[0]);
2357                 if (path->slots[0] >= nritems) {
2358                         ret = btrfs_next_leaf(root, path);
2359                         if (ret < 0)
2360                                 goto out;
2361                         if (ret > 0)
2362                                 break;
2363                         nritems = btrfs_header_nritems(path->nodes[0]);
2364                 }
2365                 leaf = path->nodes[0];
2366                 slot = path->slots[0];
2367
2368                 btrfs_item_key_to_cpu(leaf, &key, slot);
2369                 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2370                     key.objectid != btrfs_ino(src))
2371                         break;
2372
2373                 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2374                         struct btrfs_file_extent_item *extent;
2375                         int type;
2376                         u32 size;
2377                         struct btrfs_key new_key;
2378                         u64 disko = 0, diskl = 0;
2379                         u64 datao = 0, datal = 0;
2380                         u8 comp;
2381                         u64 endoff;
2382
2383                         size = btrfs_item_size_nr(leaf, slot);
2384                         read_extent_buffer(leaf, buf,
2385                                            btrfs_item_ptr_offset(leaf, slot),
2386                                            size);
2387
2388                         extent = btrfs_item_ptr(leaf, slot,
2389                                                 struct btrfs_file_extent_item);
2390                         comp = btrfs_file_extent_compression(leaf, extent);
2391                         type = btrfs_file_extent_type(leaf, extent);
2392                         if (type == BTRFS_FILE_EXTENT_REG ||
2393                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2394                                 disko = btrfs_file_extent_disk_bytenr(leaf,
2395                                                                       extent);
2396                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2397                                                                  extent);
2398                                 datao = btrfs_file_extent_offset(leaf, extent);
2399                                 datal = btrfs_file_extent_num_bytes(leaf,
2400                                                                     extent);
2401                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2402                                 /* take upper bound, may be compressed */
2403                                 datal = btrfs_file_extent_ram_bytes(leaf,
2404                                                                     extent);
2405                         }
2406                         btrfs_release_path(path);
2407
2408                         if (key.offset + datal <= off ||
2409                             key.offset >= off+len)
2410                                 goto next;
2411
2412                         memcpy(&new_key, &key, sizeof(new_key));
2413                         new_key.objectid = btrfs_ino(inode);
2414                         if (off <= key.offset)
2415                                 new_key.offset = key.offset + destoff - off;
2416                         else
2417                                 new_key.offset = destoff;
2418
2419                         /*
2420                          * 1 - adjusting old extent (we may have to split it)
2421                          * 1 - add new extent
2422                          * 1 - inode update
2423                          */
2424                         trans = btrfs_start_transaction(root, 3);
2425                         if (IS_ERR(trans)) {
2426                                 ret = PTR_ERR(trans);
2427                                 goto out;
2428                         }
2429
2430                         if (type == BTRFS_FILE_EXTENT_REG ||
2431                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2432                                 /*
2433                                  *    a  | --- range to clone ---|  b
2434                                  * | ------------- extent ------------- |
2435                                  */
2436
2437                                 /* substract range b */
2438                                 if (key.offset + datal > off + len)
2439                                         datal = off + len - key.offset;
2440
2441                                 /* substract range a */
2442                                 if (off > key.offset) {
2443                                         datao += off - key.offset;
2444                                         datal -= off - key.offset;
2445                                 }
2446
2447                                 ret = btrfs_drop_extents(trans, inode,
2448                                                          new_key.offset,
2449                                                          new_key.offset + datal,
2450                                                          &hint_byte, 1);
2451                                 BUG_ON(ret);
2452
2453                                 ret = btrfs_insert_empty_item(trans, root, path,
2454                                                               &new_key, size);
2455                                 BUG_ON(ret);
2456
2457                                 leaf = path->nodes[0];
2458                                 slot = path->slots[0];
2459                                 write_extent_buffer(leaf, buf,
2460                                             btrfs_item_ptr_offset(leaf, slot),
2461                                             size);
2462
2463                                 extent = btrfs_item_ptr(leaf, slot,
2464                                                 struct btrfs_file_extent_item);
2465
2466                                 /* disko == 0 means it's a hole */
2467                                 if (!disko)
2468                                         datao = 0;
2469
2470                                 btrfs_set_file_extent_offset(leaf, extent,
2471                                                              datao);
2472                                 btrfs_set_file_extent_num_bytes(leaf, extent,
2473                                                                 datal);
2474                                 if (disko) {
2475                                         inode_add_bytes(inode, datal);
2476                                         ret = btrfs_inc_extent_ref(trans, root,
2477                                                         disko, diskl, 0,
2478                                                         root->root_key.objectid,
2479                                                         btrfs_ino(inode),
2480                                                         new_key.offset - datao,
2481                                                         0);
2482                                         BUG_ON(ret);
2483                                 }
2484                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2485                                 u64 skip = 0;
2486                                 u64 trim = 0;
2487                                 if (off > key.offset) {
2488                                         skip = off - key.offset;
2489                                         new_key.offset += skip;
2490                                 }
2491
2492                                 if (key.offset + datal > off+len)
2493                                         trim = key.offset + datal - (off+len);
2494
2495                                 if (comp && (skip || trim)) {
2496                                         ret = -EINVAL;
2497                                         btrfs_end_transaction(trans, root);
2498                                         goto out;
2499                                 }
2500                                 size -= skip + trim;
2501                                 datal -= skip + trim;
2502
2503                                 ret = btrfs_drop_extents(trans, inode,
2504                                                          new_key.offset,
2505                                                          new_key.offset + datal,
2506                                                          &hint_byte, 1);
2507                                 BUG_ON(ret);
2508
2509                                 ret = btrfs_insert_empty_item(trans, root, path,
2510                                                               &new_key, size);
2511                                 BUG_ON(ret);
2512
2513                                 if (skip) {
2514                                         u32 start =
2515                                           btrfs_file_extent_calc_inline_size(0);
2516                                         memmove(buf+start, buf+start+skip,
2517                                                 datal);
2518                                 }
2519
2520                                 leaf = path->nodes[0];
2521                                 slot = path->slots[0];
2522                                 write_extent_buffer(leaf, buf,
2523                                             btrfs_item_ptr_offset(leaf, slot),
2524                                             size);
2525                                 inode_add_bytes(inode, datal);
2526                         }
2527
2528                         btrfs_mark_buffer_dirty(leaf);
2529                         btrfs_release_path(path);
2530
2531                         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2532
2533                         /*
2534                          * we round up to the block size at eof when
2535                          * determining which extents to clone above,
2536                          * but shouldn't round up the file size
2537                          */
2538                         endoff = new_key.offset + datal;
2539                         if (endoff > destoff+olen)
2540                                 endoff = destoff+olen;
2541                         if (endoff > inode->i_size)
2542                                 btrfs_i_size_write(inode, endoff);
2543
2544                         ret = btrfs_update_inode(trans, root, inode);
2545                         BUG_ON(ret);
2546                         btrfs_end_transaction(trans, root);
2547                 }
2548 next:
2549                 btrfs_release_path(path);
2550                 key.offset++;
2551         }
2552         ret = 0;
2553 out:
2554         btrfs_release_path(path);
2555         unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
2556 out_unlock:
2557         mutex_unlock(&src->i_mutex);
2558         mutex_unlock(&inode->i_mutex);
2559         vfree(buf);
2560         btrfs_free_path(path);
2561 out_fput:
2562         fput(src_file);
2563 out_drop_write:
2564         mnt_drop_write(file->f_path.mnt);
2565         return ret;
2566 }
2567
2568 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2569 {
2570         struct btrfs_ioctl_clone_range_args args;
2571
2572         if (copy_from_user(&args, argp, sizeof(args)))
2573                 return -EFAULT;
2574         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2575                                  args.src_length, args.dest_offset);
2576 }
2577
2578 /*
2579  * there are many ways the trans_start and trans_end ioctls can lead
2580  * to deadlocks.  They should only be used by applications that
2581  * basically own the machine, and have a very in depth understanding
2582  * of all the possible deadlocks and enospc problems.
2583  */
2584 static long btrfs_ioctl_trans_start(struct file *file)
2585 {
2586         struct inode *inode = fdentry(file)->d_inode;
2587         struct btrfs_root *root = BTRFS_I(inode)->root;
2588         struct btrfs_trans_handle *trans;
2589         int ret;
2590
2591         ret = -EPERM;
2592         if (!capable(CAP_SYS_ADMIN))
2593                 goto out;
2594
2595         ret = -EINPROGRESS;
2596         if (file->private_data)
2597                 goto out;
2598
2599         ret = -EROFS;
2600         if (btrfs_root_readonly(root))
2601                 goto out;
2602
2603         ret = mnt_want_write(file->f_path.mnt);
2604         if (ret)
2605                 goto out;
2606
2607         atomic_inc(&root->fs_info->open_ioctl_trans);
2608
2609         ret = -ENOMEM;
2610         trans = btrfs_start_ioctl_transaction(root);
2611         if (IS_ERR(trans))
2612                 goto out_drop;
2613
2614         file->private_data = trans;
2615         return 0;
2616
2617 out_drop:
2618         atomic_dec(&root->fs_info->open_ioctl_trans);
2619         mnt_drop_write(file->f_path.mnt);
2620 out:
2621         return ret;
2622 }
2623
2624 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2625 {
2626         struct inode *inode = fdentry(file)->d_inode;
2627         struct btrfs_root *root = BTRFS_I(inode)->root;
2628         struct btrfs_root *new_root;
2629         struct btrfs_dir_item *di;
2630         struct btrfs_trans_handle *trans;
2631         struct btrfs_path *path;
2632         struct btrfs_key location;
2633         struct btrfs_disk_key disk_key;
2634         struct btrfs_super_block *disk_super;
2635         u64 features;
2636         u64 objectid = 0;
2637         u64 dir_id;
2638
2639         if (!capable(CAP_SYS_ADMIN))
2640                 return -EPERM;
2641
2642         if (copy_from_user(&objectid, argp, sizeof(objectid)))
2643                 return -EFAULT;
2644
2645         if (!objectid)
2646                 objectid = root->root_key.objectid;
2647
2648         location.objectid = objectid;
2649         location.type = BTRFS_ROOT_ITEM_KEY;
2650         location.offset = (u64)-1;
2651
2652         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2653         if (IS_ERR(new_root))
2654                 return PTR_ERR(new_root);
2655
2656         if (btrfs_root_refs(&new_root->root_item) == 0)
2657                 return -ENOENT;
2658
2659         path = btrfs_alloc_path();
2660         if (!path)
2661                 return -ENOMEM;
2662         path->leave_spinning = 1;
2663
2664         trans = btrfs_start_transaction(root, 1);
2665         if (IS_ERR(trans)) {
2666                 btrfs_free_path(path);
2667                 return PTR_ERR(trans);
2668         }
2669
2670         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2671         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2672                                    dir_id, "default", 7, 1);
2673         if (IS_ERR_OR_NULL(di)) {
2674                 btrfs_free_path(path);
2675                 btrfs_end_transaction(trans, root);
2676                 printk(KERN_ERR "Umm, you don't have the default dir item, "
2677                        "this isn't going to work\n");
2678                 return -ENOENT;
2679         }
2680
2681         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2682         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2683         btrfs_mark_buffer_dirty(path->nodes[0]);
2684         btrfs_free_path(path);
2685
2686         disk_super = root->fs_info->super_copy;
2687         features = btrfs_super_incompat_flags(disk_super);
2688         if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2689                 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2690                 btrfs_set_super_incompat_flags(disk_super, features);
2691         }
2692         btrfs_end_transaction(trans, root);
2693
2694         return 0;
2695 }
2696
2697 static void get_block_group_info(struct list_head *groups_list,
2698                                  struct btrfs_ioctl_space_info *space)
2699 {
2700         struct btrfs_block_group_cache *block_group;
2701
2702         space->total_bytes = 0;
2703         space->used_bytes = 0;
2704         space->flags = 0;
2705         list_for_each_entry(block_group, groups_list, list) {
2706                 space->flags = block_group->flags;
2707                 space->total_bytes += block_group->key.offset;
2708                 space->used_bytes +=
2709                         btrfs_block_group_used(&block_group->item);
2710         }
2711 }
2712
2713 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2714 {
2715         struct btrfs_ioctl_space_args space_args;
2716         struct btrfs_ioctl_space_info space;
2717         struct btrfs_ioctl_space_info *dest;
2718         struct btrfs_ioctl_space_info *dest_orig;
2719         struct btrfs_ioctl_space_info __user *user_dest;
2720         struct btrfs_space_info *info;
2721         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2722                        BTRFS_BLOCK_GROUP_SYSTEM,
2723                        BTRFS_BLOCK_GROUP_METADATA,
2724                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2725         int num_types = 4;
2726         int alloc_size;
2727         int ret = 0;
2728         u64 slot_count = 0;
2729         int i, c;
2730
2731         if (copy_from_user(&space_args,
2732                            (struct btrfs_ioctl_space_args __user *)arg,
2733                            sizeof(space_args)))
2734                 return -EFAULT;
2735
2736         for (i = 0; i < num_types; i++) {
2737                 struct btrfs_space_info *tmp;
2738
2739                 info = NULL;
2740                 rcu_read_lock();
2741                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2742                                         list) {
2743                         if (tmp->flags == types[i]) {
2744                                 info = tmp;
2745                                 break;
2746                         }
2747                 }
2748                 rcu_read_unlock();
2749
2750                 if (!info)
2751                         continue;
2752
2753                 down_read(&info->groups_sem);
2754                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2755                         if (!list_empty(&info->block_groups[c]))
2756                                 slot_count++;
2757                 }
2758                 up_read(&info->groups_sem);
2759         }
2760
2761         /* space_slots == 0 means they are asking for a count */
2762         if (space_args.space_slots == 0) {
2763                 space_args.total_spaces = slot_count;
2764                 goto out;
2765         }
2766
2767         slot_count = min_t(u64, space_args.space_slots, slot_count);
2768
2769         alloc_size = sizeof(*dest) * slot_count;
2770
2771         /* we generally have at most 6 or so space infos, one for each raid
2772          * level.  So, a whole page should be more than enough for everyone
2773          */
2774         if (alloc_size > PAGE_CACHE_SIZE)
2775                 return -ENOMEM;
2776
2777         space_args.total_spaces = 0;
2778         dest = kmalloc(alloc_size, GFP_NOFS);
2779         if (!dest)
2780                 return -ENOMEM;
2781         dest_orig = dest;
2782
2783         /* now we have a buffer to copy into */
2784         for (i = 0; i < num_types; i++) {
2785                 struct btrfs_space_info *tmp;
2786
2787                 if (!slot_count)
2788                         break;
2789
2790                 info = NULL;
2791                 rcu_read_lock();
2792                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2793                                         list) {
2794                         if (tmp->flags == types[i]) {
2795                                 info = tmp;
2796                                 break;
2797                         }
2798                 }
2799                 rcu_read_unlock();
2800
2801                 if (!info)
2802                         continue;
2803                 down_read(&info->groups_sem);
2804                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2805                         if (!list_empty(&info->block_groups[c])) {
2806                                 get_block_group_info(&info->block_groups[c],
2807                                                      &space);
2808                                 memcpy(dest, &space, sizeof(space));
2809                                 dest++;
2810                                 space_args.total_spaces++;
2811                                 slot_count--;
2812                         }
2813                         if (!slot_count)
2814                                 break;
2815                 }
2816                 up_read(&info->groups_sem);
2817         }
2818
2819         user_dest = (struct btrfs_ioctl_space_info *)
2820                 (arg + sizeof(struct btrfs_ioctl_space_args));
2821
2822         if (copy_to_user(user_dest, dest_orig, alloc_size))
2823                 ret = -EFAULT;
2824
2825         kfree(dest_orig);
2826 out:
2827         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2828                 ret = -EFAULT;
2829
2830         return ret;
2831 }
2832
2833 /*
2834  * there are many ways the trans_start and trans_end ioctls can lead
2835  * to deadlocks.  They should only be used by applications that
2836  * basically own the machine, and have a very in depth understanding
2837  * of all the possible deadlocks and enospc problems.
2838  */
2839 long btrfs_ioctl_trans_end(struct file *file)
2840 {
2841         struct inode *inode = fdentry(file)->d_inode;
2842         struct btrfs_root *root = BTRFS_I(inode)->root;
2843         struct btrfs_trans_handle *trans;
2844
2845         trans = file->private_data;
2846         if (!trans)
2847                 return -EINVAL;
2848         file->private_data = NULL;
2849
2850         btrfs_end_transaction(trans, root);
2851
2852         atomic_dec(&root->fs_info->open_ioctl_trans);
2853
2854         mnt_drop_write(file->f_path.mnt);
2855         return 0;
2856 }
2857
2858 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2859 {
2860         struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2861         struct btrfs_trans_handle *trans;
2862         u64 transid;
2863         int ret;
2864
2865         trans = btrfs_start_transaction(root, 0);
2866         if (IS_ERR(trans))
2867                 return PTR_ERR(trans);
2868         transid = trans->transid;
2869         ret = btrfs_commit_transaction_async(trans, root, 0);
2870         if (ret) {
2871                 btrfs_end_transaction(trans, root);
2872                 return ret;
2873         }
2874
2875         if (argp)
2876                 if (copy_to_user(argp, &transid, sizeof(transid)))
2877                         return -EFAULT;
2878         return 0;
2879 }
2880
2881 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2882 {
2883         struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2884         u64 transid;
2885
2886         if (argp) {
2887                 if (copy_from_user(&transid, argp, sizeof(transid)))
2888                         return -EFAULT;
2889         } else {
2890                 transid = 0;  /* current trans */
2891         }
2892         return btrfs_wait_for_commit(root, transid);
2893 }
2894
2895 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2896 {
2897         int ret;
2898         struct btrfs_ioctl_scrub_args *sa;
2899
2900         if (!capable(CAP_SYS_ADMIN))
2901                 return -EPERM;
2902
2903         sa = memdup_user(arg, sizeof(*sa));
2904         if (IS_ERR(sa))
2905                 return PTR_ERR(sa);
2906
2907         ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
2908                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
2909
2910         if (copy_to_user(arg, sa, sizeof(*sa)))
2911                 ret = -EFAULT;
2912
2913         kfree(sa);
2914         return ret;
2915 }
2916
2917 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
2918 {
2919         if (!capable(CAP_SYS_ADMIN))
2920                 return -EPERM;
2921
2922         return btrfs_scrub_cancel(root);
2923 }
2924
2925 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
2926                                        void __user *arg)
2927 {
2928         struct btrfs_ioctl_scrub_args *sa;
2929         int ret;
2930
2931         if (!capable(CAP_SYS_ADMIN))
2932                 return -EPERM;
2933
2934         sa = memdup_user(arg, sizeof(*sa));
2935         if (IS_ERR(sa))
2936                 return PTR_ERR(sa);
2937
2938         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
2939
2940         if (copy_to_user(arg, sa, sizeof(*sa)))
2941                 ret = -EFAULT;
2942
2943         kfree(sa);
2944         return ret;
2945 }
2946
2947 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
2948 {
2949         int ret = 0;
2950         int i;
2951         u64 rel_ptr;
2952         int size;
2953         struct btrfs_ioctl_ino_path_args *ipa = NULL;
2954         struct inode_fs_paths *ipath = NULL;
2955         struct btrfs_path *path;
2956
2957         if (!capable(CAP_SYS_ADMIN))
2958                 return -EPERM;
2959
2960         path = btrfs_alloc_path();
2961         if (!path) {
2962                 ret = -ENOMEM;
2963                 goto out;
2964         }
2965
2966         ipa = memdup_user(arg, sizeof(*ipa));
2967         if (IS_ERR(ipa)) {
2968                 ret = PTR_ERR(ipa);
2969                 ipa = NULL;
2970                 goto out;
2971         }
2972
2973         size = min_t(u32, ipa->size, 4096);
2974         ipath = init_ipath(size, root, path);
2975         if (IS_ERR(ipath)) {
2976                 ret = PTR_ERR(ipath);
2977                 ipath = NULL;
2978                 goto out;
2979         }
2980
2981         ret = paths_from_inode(ipa->inum, ipath);
2982         if (ret < 0)
2983                 goto out;
2984
2985         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
2986                 rel_ptr = ipath->fspath->val[i] -
2987                           (u64)(unsigned long)ipath->fspath->val;
2988                 ipath->fspath->val[i] = rel_ptr;
2989         }
2990
2991         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
2992                            (void *)(unsigned long)ipath->fspath, size);
2993         if (ret) {
2994                 ret = -EFAULT;
2995                 goto out;
2996         }
2997
2998 out:
2999         btrfs_free_path(path);
3000         free_ipath(ipath);
3001         kfree(ipa);
3002
3003         return ret;
3004 }
3005
3006 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3007 {
3008         struct btrfs_data_container *inodes = ctx;
3009         const size_t c = 3 * sizeof(u64);
3010
3011         if (inodes->bytes_left >= c) {
3012                 inodes->bytes_left -= c;
3013                 inodes->val[inodes->elem_cnt] = inum;
3014                 inodes->val[inodes->elem_cnt + 1] = offset;
3015                 inodes->val[inodes->elem_cnt + 2] = root;
3016                 inodes->elem_cnt += 3;
3017         } else {
3018                 inodes->bytes_missing += c - inodes->bytes_left;
3019                 inodes->bytes_left = 0;
3020                 inodes->elem_missed += 3;
3021         }
3022
3023         return 0;
3024 }
3025
3026 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3027                                         void __user *arg)
3028 {
3029         int ret = 0;
3030         int size;
3031         u64 extent_item_pos;
3032         struct btrfs_ioctl_logical_ino_args *loi;
3033         struct btrfs_data_container *inodes = NULL;
3034         struct btrfs_path *path = NULL;
3035         struct btrfs_key key;
3036
3037         if (!capable(CAP_SYS_ADMIN))
3038                 return -EPERM;
3039
3040         loi = memdup_user(arg, sizeof(*loi));
3041         if (IS_ERR(loi)) {
3042                 ret = PTR_ERR(loi);
3043                 loi = NULL;
3044                 goto out;
3045         }
3046
3047         path = btrfs_alloc_path();
3048         if (!path) {
3049                 ret = -ENOMEM;
3050                 goto out;
3051         }
3052
3053         size = min_t(u32, loi->size, 4096);
3054         inodes = init_data_container(size);
3055         if (IS_ERR(inodes)) {
3056                 ret = PTR_ERR(inodes);
3057                 inodes = NULL;
3058                 goto out;
3059         }
3060
3061         ret = extent_from_logical(root->fs_info, loi->logical, path, &key);
3062         btrfs_release_path(path);
3063
3064         if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
3065                 ret = -ENOENT;
3066         if (ret < 0)
3067                 goto out;
3068
3069         extent_item_pos = loi->logical - key.objectid;
3070         ret = iterate_extent_inodes(root->fs_info, path, key.objectid,
3071                                         extent_item_pos, build_ino_list,
3072                                         inodes);
3073
3074         if (ret < 0)
3075                 goto out;
3076
3077         ret = copy_to_user((void *)(unsigned long)loi->inodes,
3078                            (void *)(unsigned long)inodes, size);
3079         if (ret)
3080                 ret = -EFAULT;
3081
3082 out:
3083         btrfs_free_path(path);
3084         kfree(inodes);
3085         kfree(loi);
3086
3087         return ret;
3088 }
3089
3090 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3091                                struct btrfs_ioctl_balance_args *bargs)
3092 {
3093         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3094
3095         bargs->flags = bctl->flags;
3096
3097         if (atomic_read(&fs_info->balance_running))
3098                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3099         if (atomic_read(&fs_info->balance_pause_req))
3100                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3101         if (atomic_read(&fs_info->balance_cancel_req))
3102                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3103
3104         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3105         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3106         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3107
3108         if (lock) {
3109                 spin_lock(&fs_info->balance_lock);
3110                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3111                 spin_unlock(&fs_info->balance_lock);
3112         } else {
3113                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3114         }
3115 }
3116
3117 static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg)
3118 {
3119         struct btrfs_fs_info *fs_info = root->fs_info;
3120         struct btrfs_ioctl_balance_args *bargs;
3121         struct btrfs_balance_control *bctl;
3122         int ret;
3123
3124         if (!capable(CAP_SYS_ADMIN))
3125                 return -EPERM;
3126
3127         if (fs_info->sb->s_flags & MS_RDONLY)
3128                 return -EROFS;
3129
3130         mutex_lock(&fs_info->volume_mutex);
3131         mutex_lock(&fs_info->balance_mutex);
3132
3133         if (arg) {
3134                 bargs = memdup_user(arg, sizeof(*bargs));
3135                 if (IS_ERR(bargs)) {
3136                         ret = PTR_ERR(bargs);
3137                         goto out;
3138                 }
3139
3140                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3141                         if (!fs_info->balance_ctl) {
3142                                 ret = -ENOTCONN;
3143                                 goto out_bargs;
3144                         }
3145
3146                         bctl = fs_info->balance_ctl;
3147                         spin_lock(&fs_info->balance_lock);
3148                         bctl->flags |= BTRFS_BALANCE_RESUME;
3149                         spin_unlock(&fs_info->balance_lock);
3150
3151                         goto do_balance;
3152                 }
3153         } else {
3154                 bargs = NULL;
3155         }
3156
3157         if (fs_info->balance_ctl) {
3158                 ret = -EINPROGRESS;
3159                 goto out_bargs;
3160         }
3161
3162         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3163         if (!bctl) {
3164                 ret = -ENOMEM;
3165                 goto out_bargs;
3166         }
3167
3168         bctl->fs_info = fs_info;
3169         if (arg) {
3170                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3171                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3172                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3173
3174                 bctl->flags = bargs->flags;
3175         } else {
3176                 /* balance everything - no filters */
3177                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3178         }
3179
3180 do_balance:
3181         ret = btrfs_balance(bctl, bargs);
3182         /*
3183          * bctl is freed in __cancel_balance or in free_fs_info if
3184          * restriper was paused all the way until unmount
3185          */
3186         if (arg) {
3187                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3188                         ret = -EFAULT;
3189         }
3190
3191 out_bargs:
3192         kfree(bargs);
3193 out:
3194         mutex_unlock(&fs_info->balance_mutex);
3195         mutex_unlock(&fs_info->volume_mutex);
3196         return ret;
3197 }
3198
3199 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3200 {
3201         if (!capable(CAP_SYS_ADMIN))
3202                 return -EPERM;
3203
3204         switch (cmd) {
3205         case BTRFS_BALANCE_CTL_PAUSE:
3206                 return btrfs_pause_balance(root->fs_info);
3207         case BTRFS_BALANCE_CTL_CANCEL:
3208                 return btrfs_cancel_balance(root->fs_info);
3209         }
3210
3211         return -EINVAL;
3212 }
3213
3214 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3215                                          void __user *arg)
3216 {
3217         struct btrfs_fs_info *fs_info = root->fs_info;
3218         struct btrfs_ioctl_balance_args *bargs;
3219         int ret = 0;
3220
3221         if (!capable(CAP_SYS_ADMIN))
3222                 return -EPERM;
3223
3224         mutex_lock(&fs_info->balance_mutex);
3225         if (!fs_info->balance_ctl) {
3226                 ret = -ENOTCONN;
3227                 goto out;
3228         }
3229
3230         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3231         if (!bargs) {
3232                 ret = -ENOMEM;
3233                 goto out;
3234         }
3235
3236         update_ioctl_balance_args(fs_info, 1, bargs);
3237
3238         if (copy_to_user(arg, bargs, sizeof(*bargs)))
3239                 ret = -EFAULT;
3240
3241         kfree(bargs);
3242 out:
3243         mutex_unlock(&fs_info->balance_mutex);
3244         return ret;
3245 }
3246
3247 long btrfs_ioctl(struct file *file, unsigned int
3248                 cmd, unsigned long arg)
3249 {
3250         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3251         void __user *argp = (void __user *)arg;
3252
3253         switch (cmd) {
3254         case FS_IOC_GETFLAGS:
3255                 return btrfs_ioctl_getflags(file, argp);
3256         case FS_IOC_SETFLAGS:
3257                 return btrfs_ioctl_setflags(file, argp);
3258         case FS_IOC_GETVERSION:
3259                 return btrfs_ioctl_getversion(file, argp);
3260         case FITRIM:
3261                 return btrfs_ioctl_fitrim(file, argp);
3262         case BTRFS_IOC_SNAP_CREATE:
3263                 return btrfs_ioctl_snap_create(file, argp, 0);
3264         case BTRFS_IOC_SNAP_CREATE_V2:
3265                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
3266         case BTRFS_IOC_SUBVOL_CREATE:
3267                 return btrfs_ioctl_snap_create(file, argp, 1);
3268         case BTRFS_IOC_SNAP_DESTROY:
3269                 return btrfs_ioctl_snap_destroy(file, argp);
3270         case BTRFS_IOC_SUBVOL_GETFLAGS:
3271                 return btrfs_ioctl_subvol_getflags(file, argp);
3272         case BTRFS_IOC_SUBVOL_SETFLAGS:
3273                 return btrfs_ioctl_subvol_setflags(file, argp);
3274         case BTRFS_IOC_DEFAULT_SUBVOL:
3275                 return btrfs_ioctl_default_subvol(file, argp);
3276         case BTRFS_IOC_DEFRAG:
3277                 return btrfs_ioctl_defrag(file, NULL);
3278         case BTRFS_IOC_DEFRAG_RANGE:
3279                 return btrfs_ioctl_defrag(file, argp);
3280         case BTRFS_IOC_RESIZE:
3281                 return btrfs_ioctl_resize(root, argp);
3282         case BTRFS_IOC_ADD_DEV:
3283                 return btrfs_ioctl_add_dev(root, argp);
3284         case BTRFS_IOC_RM_DEV:
3285                 return btrfs_ioctl_rm_dev(root, argp);
3286         case BTRFS_IOC_FS_INFO:
3287                 return btrfs_ioctl_fs_info(root, argp);
3288         case BTRFS_IOC_DEV_INFO:
3289                 return btrfs_ioctl_dev_info(root, argp);
3290         case BTRFS_IOC_BALANCE:
3291                 return btrfs_ioctl_balance(root, NULL);
3292         case BTRFS_IOC_CLONE:
3293                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
3294         case BTRFS_IOC_CLONE_RANGE:
3295                 return btrfs_ioctl_clone_range(file, argp);
3296         case BTRFS_IOC_TRANS_START:
3297                 return btrfs_ioctl_trans_start(file);
3298         case BTRFS_IOC_TRANS_END:
3299                 return btrfs_ioctl_trans_end(file);
3300         case BTRFS_IOC_TREE_SEARCH:
3301                 return btrfs_ioctl_tree_search(file, argp);
3302         case BTRFS_IOC_INO_LOOKUP:
3303                 return btrfs_ioctl_ino_lookup(file, argp);
3304         case BTRFS_IOC_INO_PATHS:
3305                 return btrfs_ioctl_ino_to_path(root, argp);
3306         case BTRFS_IOC_LOGICAL_INO:
3307                 return btrfs_ioctl_logical_to_ino(root, argp);
3308         case BTRFS_IOC_SPACE_INFO:
3309                 return btrfs_ioctl_space_info(root, argp);
3310         case BTRFS_IOC_SYNC:
3311                 btrfs_sync_fs(file->f_dentry->d_sb, 1);
3312                 return 0;
3313         case BTRFS_IOC_START_SYNC:
3314                 return btrfs_ioctl_start_sync(file, argp);
3315         case BTRFS_IOC_WAIT_SYNC:
3316                 return btrfs_ioctl_wait_sync(file, argp);
3317         case BTRFS_IOC_SCRUB:
3318                 return btrfs_ioctl_scrub(root, argp);
3319         case BTRFS_IOC_SCRUB_CANCEL:
3320                 return btrfs_ioctl_scrub_cancel(root, argp);
3321         case BTRFS_IOC_SCRUB_PROGRESS:
3322                 return btrfs_ioctl_scrub_progress(root, argp);
3323         case BTRFS_IOC_BALANCE_V2:
3324                 return btrfs_ioctl_balance(root, argp);
3325         case BTRFS_IOC_BALANCE_CTL:
3326                 return btrfs_ioctl_balance_ctl(root, arg);
3327         case BTRFS_IOC_BALANCE_PROGRESS:
3328                 return btrfs_ioctl_balance_progress(root, argp);
3329         }
3330
3331         return -ENOTTY;
3332 }