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 <linux/uuid.h>
  45 #include <linux/btrfs.h>
  46 #include "compat.h"
  47 #include "ctree.h"
  48 #include "disk-io.h"
  49 #include "transaction.h"
  50 #include "btrfs_inode.h"
  51 #include "print-tree.h"
  52 #include "volumes.h"
  53 #include "locking.h"
  54 #include "inode-map.h"
  55 #include "backref.h"
  56 #include "rcu-string.h"
  57 #include "send.h"
  58 #include "dev-replace.h"
  59
  60 /* Mask out flags that are inappropriate for the given type of inode. */
  61 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
  62 {
  63         if (S_ISDIR(mode))
  64                 return flags;
  65         else if (S_ISREG(mode))
  66                 return flags & ~FS_DIRSYNC_FL;
  67         else
  68                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
  69 }
  70
  71 /*
  72  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
  73  */
  74 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
  75 {
  76         unsigned int iflags = 0;
  77
  78         if (flags & BTRFS_INODE_SYNC)
  79                 iflags |= FS_SYNC_FL;
  80         if (flags & BTRFS_INODE_IMMUTABLE)
  81                 iflags |= FS_IMMUTABLE_FL;
  82         if (flags & BTRFS_INODE_APPEND)
  83                 iflags |= FS_APPEND_FL;
  84         if (flags & BTRFS_INODE_NODUMP)
  85                 iflags |= FS_NODUMP_FL;
  86         if (flags & BTRFS_INODE_NOATIME)
  87                 iflags |= FS_NOATIME_FL;
  88         if (flags & BTRFS_INODE_DIRSYNC)
  89                 iflags |= FS_DIRSYNC_FL;
  90         if (flags & BTRFS_INODE_NODATACOW)
  91                 iflags |= FS_NOCOW_FL;
  92
  93         if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
  94                 iflags |= FS_COMPR_FL;
  95         else if (flags & BTRFS_INODE_NOCOMPRESS)
  96                 iflags |= FS_NOCOMP_FL;
  97
  98         return iflags;
  99 }
 100
 101 /*
 102  * Update inode->i_flags based on the btrfs internal flags.
 103  */
 104 void btrfs_update_iflags(struct inode *inode)
 105 {
 106         struct btrfs_inode *ip = BTRFS_I(inode);
 107
 108         inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
 109
 110         if (ip->flags & BTRFS_INODE_SYNC)
 111                 inode->i_flags |= S_SYNC;
 112         if (ip->flags & BTRFS_INODE_IMMUTABLE)
 113                 inode->i_flags |= S_IMMUTABLE;
 114         if (ip->flags & BTRFS_INODE_APPEND)
 115                 inode->i_flags |= S_APPEND;
 116         if (ip->flags & BTRFS_INODE_NOATIME)
 117                 inode->i_flags |= S_NOATIME;
 118         if (ip->flags & BTRFS_INODE_DIRSYNC)
 119                 inode->i_flags |= S_DIRSYNC;
 120 }
 121
 122 /*
 123  * Inherit flags from the parent inode.
 124  *
 125  * Currently only the compression flags and the cow flags are inherited.
 126  */
 127 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 128 {
 129         unsigned int flags;
 130
 131         if (!dir)
 132                 return;
 133
 134         flags = BTRFS_I(dir)->flags;
 135
 136         if (flags & BTRFS_INODE_NOCOMPRESS) {
 137                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 138                 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 139         } else if (flags & BTRFS_INODE_COMPRESS) {
 140                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 141                 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 142         }
 143
 144         if (flags & BTRFS_INODE_NODATACOW) {
 145                 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 146                 if (S_ISREG(inode->i_mode))
 147                         BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
 148         }
 149
 150         btrfs_update_iflags(inode);
 151 }
 152
 153 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 154 {
 155         struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
 156         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 157
 158         if (copy_to_user(arg, &flags, sizeof(flags)))
 159                 return -EFAULT;
 160         return 0;
 161 }
 162
 163 static int check_flags(unsigned int flags)
 164 {
 165         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 166                       FS_NOATIME_FL | FS_NODUMP_FL | \
 167                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 168                       FS_NOCOMP_FL | FS_COMPR_FL |
 169                       FS_NOCOW_FL))
 170                 return -EOPNOTSUPP;
 171
 172         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 173                 return -EINVAL;
 174
 175         return 0;
 176 }
 177
 178 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 179 {
 180         struct inode *inode = file->f_path.dentry->d_inode;
 181         struct btrfs_inode *ip = BTRFS_I(inode);
 182         struct btrfs_root *root = ip->root;
 183         struct btrfs_trans_handle *trans;
 184         unsigned int flags, oldflags;
 185         int ret;
 186         u64 ip_oldflags;
 187         unsigned int i_oldflags;
 188         umode_t mode;
 189
 190         if (btrfs_root_readonly(root))
 191                 return -EROFS;
 192
 193         if (copy_from_user(&flags, arg, sizeof(flags)))
 194                 return -EFAULT;
 195
 196         ret = check_flags(flags);
 197         if (ret)
 198                 return ret;
 199
 200         if (!inode_owner_or_capable(inode))
 201                 return -EACCES;
 202
 203         ret = mnt_want_write_file(file);
 204         if (ret)
 205                 return ret;
 206
 207         mutex_lock(&inode->i_mutex);
 208
 209         ip_oldflags = ip->flags;
 210         i_oldflags = inode->i_flags;
 211         mode = inode->i_mode;
 212
 213         flags = btrfs_mask_flags(inode->i_mode, flags);
 214         oldflags = btrfs_flags_to_ioctl(ip->flags);
 215         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 216                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 217                         ret = -EPERM;
 218                         goto out_unlock;
 219                 }
 220         }
 221
 222         if (flags & FS_SYNC_FL)
 223                 ip->flags |= BTRFS_INODE_SYNC;
 224         else
 225                 ip->flags &= ~BTRFS_INODE_SYNC;
 226         if (flags & FS_IMMUTABLE_FL)
 227                 ip->flags |= BTRFS_INODE_IMMUTABLE;
 228         else
 229                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 230         if (flags & FS_APPEND_FL)
 231                 ip->flags |= BTRFS_INODE_APPEND;
 232         else
 233                 ip->flags &= ~BTRFS_INODE_APPEND;
 234         if (flags & FS_NODUMP_FL)
 235                 ip->flags |= BTRFS_INODE_NODUMP;
 236         else
 237                 ip->flags &= ~BTRFS_INODE_NODUMP;
 238         if (flags & FS_NOATIME_FL)
 239                 ip->flags |= BTRFS_INODE_NOATIME;
 240         else
 241                 ip->flags &= ~BTRFS_INODE_NOATIME;
 242         if (flags & FS_DIRSYNC_FL)
 243                 ip->flags |= BTRFS_INODE_DIRSYNC;
 244         else
 245                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
 246         if (flags & FS_NOCOW_FL) {
 247                 if (S_ISREG(mode)) {
 248                         /*
 249                          * It's safe to turn csums off here, no extents exist.
 250                          * Otherwise we want the flag to reflect the real COW
 251                          * status of the file and will not set it.
 252                          */
 253                         if (inode->i_size == 0)
 254                                 ip->flags |= BTRFS_INODE_NODATACOW
 255                                            | BTRFS_INODE_NODATASUM;
 256                 } else {
 257                         ip->flags |= BTRFS_INODE_NODATACOW;
 258                 }
 259         } else {
 260                 /*
 261                  * Revert back under same assuptions as above
 262                  */
 263                 if (S_ISREG(mode)) {
 264                         if (inode->i_size == 0)
 265                                 ip->flags &= ~(BTRFS_INODE_NODATACOW
 266                                              | BTRFS_INODE_NODATASUM);
 267                 } else {
 268                         ip->flags &= ~BTRFS_INODE_NODATACOW;
 269                 }
 270         }
 271
 272         /*
 273          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 274          * flag may be changed automatically if compression code won't make
 275          * things smaller.
 276          */
 277         if (flags & FS_NOCOMP_FL) {
 278                 ip->flags &= ~BTRFS_INODE_COMPRESS;
 279                 ip->flags |= BTRFS_INODE_NOCOMPRESS;
 280         } else if (flags & FS_COMPR_FL) {
 281                 ip->flags |= BTRFS_INODE_COMPRESS;
 282                 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 283         } else {
 284                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 285         }
 286
 287         trans = btrfs_start_transaction(root, 1);
 288         if (IS_ERR(trans)) {
 289                 ret = PTR_ERR(trans);
 290                 goto out_drop;
 291         }
 292
 293         btrfs_update_iflags(inode);
 294         inode_inc_iversion(inode);
 295         inode->i_ctime = CURRENT_TIME;
 296         ret = btrfs_update_inode(trans, root, inode);
 297
 298         btrfs_end_transaction(trans, root);
 299  out_drop:
 300         if (ret) {
 301                 ip->flags = ip_oldflags;
 302                 inode->i_flags = i_oldflags;
 303         }
 304
 305  out_unlock:
 306         mutex_unlock(&inode->i_mutex);
 307         mnt_drop_write_file(file);
 308         return ret;
 309 }
 310
 311 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 312 {
 313         struct inode *inode = file->f_path.dentry->d_inode;
 314
 315         return put_user(inode->i_generation, arg);
 316 }
 317
 318 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 319 {
 320         struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
 321         struct btrfs_device *device;
 322         struct request_queue *q;
 323         struct fstrim_range range;
 324         u64 minlen = ULLONG_MAX;
 325         u64 num_devices = 0;
 326         u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 327         int ret;
 328
 329         if (!capable(CAP_SYS_ADMIN))
 330                 return -EPERM;
 331
 332         rcu_read_lock();
 333         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 334                                 dev_list) {
 335                 if (!device->bdev)
 336                         continue;
 337                 q = bdev_get_queue(device->bdev);
 338                 if (blk_queue_discard(q)) {
 339                         num_devices++;
 340                         minlen = min((u64)q->limits.discard_granularity,
 341                                      minlen);
 342                 }
 343         }
 344         rcu_read_unlock();
 345
 346         if (!num_devices)
 347                 return -EOPNOTSUPP;
 348         if (copy_from_user(&range, arg, sizeof(range)))
 349                 return -EFAULT;
 350         if (range.start > total_bytes ||
 351             range.len < fs_info->sb->s_blocksize)
 352                 return -EINVAL;
 353
 354         range.len = min(range.len, total_bytes - range.start);
 355         range.minlen = max(range.minlen, minlen);
 356         ret = btrfs_trim_fs(fs_info->tree_root, &range);
 357         if (ret < 0)
 358                 return ret;
 359
 360         if (copy_to_user(arg, &range, sizeof(range)))
 361                 return -EFAULT;
 362
 363         return 0;
 364 }
 365
 366 static noinline int create_subvol(struct btrfs_root *root,
 367                                   struct dentry *dentry,
 368                                   char *name, int namelen,
 369                                   u64 *async_transid,
 370                                   struct btrfs_qgroup_inherit *inherit)
 371 {
 372         struct btrfs_trans_handle *trans;
 373         struct btrfs_key key;
 374         struct btrfs_root_item root_item;
 375         struct btrfs_inode_item *inode_item;
 376         struct extent_buffer *leaf;
 377         struct btrfs_root *new_root;
 378         struct dentry *parent = dentry->d_parent;
 379         struct inode *dir;
 380         struct timespec cur_time = CURRENT_TIME;
 381         int ret;
 382         int err;
 383         u64 objectid;
 384         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 385         u64 index = 0;
 386         uuid_le new_uuid;
 387
 388         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 389         if (ret)
 390                 return ret;
 391
 392         dir = parent->d_inode;
 393
 394         /*
 395          * 1 - inode item
 396          * 2 - refs
 397          * 1 - root item
 398          * 2 - dir items
 399          */
 400         trans = btrfs_start_transaction(root, 6);
 401         if (IS_ERR(trans))
 402                 return PTR_ERR(trans);
 403
 404         ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
 405         if (ret)
 406                 goto fail;
 407
 408         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
 409                                       0, objectid, NULL, 0, 0, 0);
 410         if (IS_ERR(leaf)) {
 411                 ret = PTR_ERR(leaf);
 412                 goto fail;
 413         }
 414
 415         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 416         btrfs_set_header_bytenr(leaf, leaf->start);
 417         btrfs_set_header_generation(leaf, trans->transid);
 418         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 419         btrfs_set_header_owner(leaf, objectid);
 420
 421         write_extent_buffer(leaf, root->fs_info->fsid,
 422                             (unsigned long)btrfs_header_fsid(leaf),
 423                             BTRFS_FSID_SIZE);
 424         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 425                             (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
 426                             BTRFS_UUID_SIZE);
 427         btrfs_mark_buffer_dirty(leaf);
 428
 429         memset(&root_item, 0, sizeof(root_item));
 430
 431         inode_item = &root_item.inode;
 432         inode_item->generation = cpu_to_le64(1);
 433         inode_item->size = cpu_to_le64(3);
 434         inode_item->nlink = cpu_to_le32(1);
 435         inode_item->nbytes = cpu_to_le64(root->leafsize);
 436         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 437
 438         root_item.flags = 0;
 439         root_item.byte_limit = 0;
 440         inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
 441
 442         btrfs_set_root_bytenr(&root_item, leaf->start);
 443         btrfs_set_root_generation(&root_item, trans->transid);
 444         btrfs_set_root_level(&root_item, 0);
 445         btrfs_set_root_refs(&root_item, 1);
 446         btrfs_set_root_used(&root_item, leaf->len);
 447         btrfs_set_root_last_snapshot(&root_item, 0);
 448
 449         btrfs_set_root_generation_v2(&root_item,
 450                         btrfs_root_generation(&root_item));
 451         uuid_le_gen(&new_uuid);
 452         memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
 453         root_item.otime.sec = cpu_to_le64(cur_time.tv_sec);
 454         root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec);
 455         root_item.ctime = root_item.otime;
 456         btrfs_set_root_ctransid(&root_item, trans->transid);
 457         btrfs_set_root_otransid(&root_item, trans->transid);
 458
 459         btrfs_tree_unlock(leaf);
 460         free_extent_buffer(leaf);
 461         leaf = NULL;
 462
 463         btrfs_set_root_dirid(&root_item, new_dirid);
 464
 465         key.objectid = objectid;
 466         key.offset = 0;
 467         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 468         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 469                                 &root_item);
 470         if (ret)
 471                 goto fail;
 472
 473         key.offset = (u64)-1;
 474         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 475         if (IS_ERR(new_root)) {
 476                 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 477                 ret = PTR_ERR(new_root);
 478                 goto fail;
 479         }
 480
 481         btrfs_record_root_in_trans(trans, new_root);
 482
 483         ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
 484         if (ret) {
 485                 /* We potentially lose an unused inode item here */
 486                 btrfs_abort_transaction(trans, root, ret);
 487                 goto fail;
 488         }
 489
 490         /*
 491          * insert the directory item
 492          */
 493         ret = btrfs_set_inode_index(dir, &index);
 494         if (ret) {
 495                 btrfs_abort_transaction(trans, root, ret);
 496                 goto fail;
 497         }
 498
 499         ret = btrfs_insert_dir_item(trans, root,
 500                                     name, namelen, dir, &key,
 501                                     BTRFS_FT_DIR, index);
 502         if (ret) {
 503                 btrfs_abort_transaction(trans, root, ret);
 504                 goto fail;
 505         }
 506
 507         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 508         ret = btrfs_update_inode(trans, root, dir);
 509         BUG_ON(ret);
 510
 511         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 512                                  objectid, root->root_key.objectid,
 513                                  btrfs_ino(dir), index, name, namelen);
 514
 515         BUG_ON(ret);
 516
 517 fail:
 518         if (async_transid) {
 519                 *async_transid = trans->transid;
 520                 err = btrfs_commit_transaction_async(trans, root, 1);
 521         } else {
 522                 err = btrfs_commit_transaction(trans, root);
 523         }
 524         if (err && !ret)
 525                 ret = err;
 526
 527         if (!ret)
 528                 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 529
 530         return ret;
 531 }
 532
 533 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
 534                            char *name, int namelen, u64 *async_transid,
 535                            bool readonly, struct btrfs_qgroup_inherit *inherit)
 536 {
 537         struct inode *inode;
 538         struct btrfs_pending_snapshot *pending_snapshot;
 539         struct btrfs_trans_handle *trans;
 540         int ret;
 541
 542         if (!root->ref_cows)
 543                 return -EINVAL;
 544
 545         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 546         if (!pending_snapshot)
 547                 return -ENOMEM;
 548
 549         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 550                              BTRFS_BLOCK_RSV_TEMP);
 551         pending_snapshot->dentry = dentry;
 552         pending_snapshot->root = root;
 553         pending_snapshot->readonly = readonly;
 554         pending_snapshot->inherit = inherit;
 555
 556         trans = btrfs_start_transaction(root->fs_info->extent_root, 6);
 557         if (IS_ERR(trans)) {
 558                 ret = PTR_ERR(trans);
 559                 goto fail;
 560         }
 561
 562         ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
 563         BUG_ON(ret);
 564
 565         spin_lock(&root->fs_info->trans_lock);
 566         list_add(&pending_snapshot->list,
 567                  &trans->transaction->pending_snapshots);
 568         spin_unlock(&root->fs_info->trans_lock);
 569         if (async_transid) {
 570                 *async_transid = trans->transid;
 571                 ret = btrfs_commit_transaction_async(trans,
 572                                      root->fs_info->extent_root, 1);
 573         } else {
 574                 ret = btrfs_commit_transaction(trans,
 575                                                root->fs_info->extent_root);
 576         }
 577         if (ret) {
 578                 /* cleanup_transaction has freed this for us */
 579                 if (trans->aborted)
 580                         pending_snapshot = NULL;
 581                 goto fail;
 582         }
 583
 584         ret = pending_snapshot->error;
 585         if (ret)
 586                 goto fail;
 587
 588         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 589         if (ret)
 590                 goto fail;
 591
 592         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 593         if (IS_ERR(inode)) {
 594                 ret = PTR_ERR(inode);
 595                 goto fail;
 596         }
 597         BUG_ON(!inode);
 598         d_instantiate(dentry, inode);
 599         ret = 0;
 600 fail:
 601         kfree(pending_snapshot);
 602         return ret;
 603 }
 604
 605 /*  copy of check_sticky in fs/namei.c()
 606 * It's inline, so penalty for filesystems that don't use sticky bit is
 607 * minimal.
 608 */
 609 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 610 {
 611         kuid_t fsuid = current_fsuid();
 612
 613         if (!(dir->i_mode & S_ISVTX))
 614                 return 0;
 615         if (uid_eq(inode->i_uid, fsuid))
 616                 return 0;
 617         if (uid_eq(dir->i_uid, fsuid))
 618                 return 0;
 619         return !capable(CAP_FOWNER);
 620 }
 621
 622 /*  copy of may_delete in fs/namei.c()
 623  *      Check whether we can remove a link victim from directory dir, check
 624  *  whether the type of victim is right.
 625  *  1. We can't do it if dir is read-only (done in permission())
 626  *  2. We should have write and exec permissions on dir
 627  *  3. We can't remove anything from append-only dir
 628  *  4. We can't do anything with immutable dir (done in permission())
 629  *  5. If the sticky bit on dir is set we should either
 630  *      a. be owner of dir, or
 631  *      b. be owner of victim, or
 632  *      c. have CAP_FOWNER capability
 633  *  6. If the victim is append-only or immutable we can't do antyhing with
 634  *     links pointing to it.
 635  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 636  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 637  *  9. We can't remove a root or mountpoint.
 638  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 639  *     nfs_async_unlink().
 640  */
 641
 642 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
 643 {
 644         int error;
 645
 646         if (!victim->d_inode)
 647                 return -ENOENT;
 648
 649         BUG_ON(victim->d_parent->d_inode != dir);
 650         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 651
 652         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 653         if (error)
 654                 return error;
 655         if (IS_APPEND(dir))
 656                 return -EPERM;
 657         if (btrfs_check_sticky(dir, victim->d_inode)||
 658                 IS_APPEND(victim->d_inode)||
 659             IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 660                 return -EPERM;
 661         if (isdir) {
 662                 if (!S_ISDIR(victim->d_inode->i_mode))
 663                         return -ENOTDIR;
 664                 if (IS_ROOT(victim))
 665                         return -EBUSY;
 666         } else if (S_ISDIR(victim->d_inode->i_mode))
 667                 return -EISDIR;
 668         if (IS_DEADDIR(dir))
 669                 return -ENOENT;
 670         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 671                 return -EBUSY;
 672         return 0;
 673 }
 674
 675 /* copy of may_create in fs/namei.c() */
 676 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 677 {
 678         if (child->d_inode)
 679                 return -EEXIST;
 680         if (IS_DEADDIR(dir))
 681                 return -ENOENT;
 682         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 683 }
 684
 685 /*
 686  * Create a new subvolume below @parent.  This is largely modeled after
 687  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 688  * inside this filesystem so it's quite a bit simpler.
 689  */
 690 static noinline int btrfs_mksubvol(struct path *parent,
 691                                    char *name, int namelen,
 692                                    struct btrfs_root *snap_src,
 693                                    u64 *async_transid, bool readonly,
 694                                    struct btrfs_qgroup_inherit *inherit)
 695 {
 696         struct inode *dir  = parent->dentry->d_inode;
 697         struct dentry *dentry;
 698         int error;
 699
 700         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
 701
 702         dentry = lookup_one_len(name, parent->dentry, namelen);
 703         error = PTR_ERR(dentry);
 704         if (IS_ERR(dentry))
 705                 goto out_unlock;
 706
 707         error = -EEXIST;
 708         if (dentry->d_inode)
 709                 goto out_dput;
 710
 711         error = btrfs_may_create(dir, dentry);
 712         if (error)
 713                 goto out_dput;
 714
 715         /*
 716          * even if this name doesn't exist, we may get hash collisions.
 717          * check for them now when we can safely fail
 718          */
 719         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 720                                                dir->i_ino, name,
 721                                                namelen);
 722         if (error)
 723                 goto out_dput;
 724
 725         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 726
 727         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 728                 goto out_up_read;
 729
 730         if (snap_src) {
 731                 error = create_snapshot(snap_src, dentry, name, namelen,
 732                                         async_transid, readonly, inherit);
 733         } else {
 734                 error = create_subvol(BTRFS_I(dir)->root, dentry,
 735                                       name, namelen, async_transid, inherit);
 736         }
 737         if (!error)
 738                 fsnotify_mkdir(dir, dentry);
 739 out_up_read:
 740         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 741 out_dput:
 742         dput(dentry);
 743 out_unlock:
 744         mutex_unlock(&dir->i_mutex);
 745         return error;
 746 }
 747
 748 /*
 749  * When we're defragging a range, we don't want to kick it off again
 750  * if it is really just waiting for delalloc to send it down.
 751  * If we find a nice big extent or delalloc range for the bytes in the
 752  * file you want to defrag, we return 0 to let you know to skip this
 753  * part of the file
 754  */
 755 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
 756 {
 757         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 758         struct extent_map *em = NULL;
 759         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 760         u64 end;
 761
 762         read_lock(&em_tree->lock);
 763         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 764         read_unlock(&em_tree->lock);
 765
 766         if (em) {
 767                 end = extent_map_end(em);
 768                 free_extent_map(em);
 769                 if (end - offset > thresh)
 770                         return 0;
 771         }
 772         /* if we already have a nice delalloc here, just stop */
 773         thresh /= 2;
 774         end = count_range_bits(io_tree, &offset, offset + thresh,
 775                                thresh, EXTENT_DELALLOC, 1);
 776         if (end >= thresh)
 777                 return 0;
 778         return 1;
 779 }
 780
 781 /*
 782  * helper function to walk through a file and find extents
 783  * newer than a specific transid, and smaller than thresh.
 784  *
 785  * This is used by the defragging code to find new and small
 786  * extents
 787  */
 788 static int find_new_extents(struct btrfs_root *root,
 789                             struct inode *inode, u64 newer_than,
 790                             u64 *off, int thresh)
 791 {
 792         struct btrfs_path *path;
 793         struct btrfs_key min_key;
 794         struct btrfs_key max_key;
 795         struct extent_buffer *leaf;
 796         struct btrfs_file_extent_item *extent;
 797         int type;
 798         int ret;
 799         u64 ino = btrfs_ino(inode);
 800
 801         path = btrfs_alloc_path();
 802         if (!path)
 803                 return -ENOMEM;
 804
 805         min_key.objectid = ino;
 806         min_key.type = BTRFS_EXTENT_DATA_KEY;
 807         min_key.offset = *off;
 808
 809         max_key.objectid = ino;
 810         max_key.type = (u8)-1;
 811         max_key.offset = (u64)-1;
 812
 813         path->keep_locks = 1;
 814
 815         while(1) {
 816                 ret = btrfs_search_forward(root, &min_key, &max_key,
 817                                            path, newer_than);
 818                 if (ret != 0)
 819                         goto none;
 820                 if (min_key.objectid != ino)
 821                         goto none;
 822                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 823                         goto none;
 824
 825                 leaf = path->nodes[0];
 826                 extent = btrfs_item_ptr(leaf, path->slots[0],
 827                                         struct btrfs_file_extent_item);
 828
 829                 type = btrfs_file_extent_type(leaf, extent);
 830                 if (type == BTRFS_FILE_EXTENT_REG &&
 831                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 832                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 833                         *off = min_key.offset;
 834                         btrfs_free_path(path);
 835                         return 0;
 836                 }
 837
 838                 if (min_key.offset == (u64)-1)
 839                         goto none;
 840
 841                 min_key.offset++;
 842                 btrfs_release_path(path);
 843         }
 844 none:
 845         btrfs_free_path(path);
 846         return -ENOENT;
 847 }
 848
 849 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 850 {
 851         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 852         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 853         struct extent_map *em;
 854         u64 len = PAGE_CACHE_SIZE;
 855
 856         /*
 857          * hopefully we have this extent in the tree already, try without
 858          * the full extent lock
 859          */
 860         read_lock(&em_tree->lock);
 861         em = lookup_extent_mapping(em_tree, start, len);
 862         read_unlock(&em_tree->lock);
 863
 864         if (!em) {
 865                 /* get the big lock and read metadata off disk */
 866                 lock_extent(io_tree, start, start + len - 1);
 867                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 868                 unlock_extent(io_tree, start, start + len - 1);
 869
 870                 if (IS_ERR(em))
 871                         return NULL;
 872         }
 873
 874         return em;
 875 }
 876
 877 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
 878 {
 879         struct extent_map *next;
 880         bool ret = true;
 881
 882         /* this is the last extent */
 883         if (em->start + em->len >= i_size_read(inode))
 884                 return false;
 885
 886         next = defrag_lookup_extent(inode, em->start + em->len);
 887         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
 888                 ret = false;
 889
 890         free_extent_map(next);
 891         return ret;
 892 }
 893
 894 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
 895                                u64 *last_len, u64 *skip, u64 *defrag_end,
 896                                int compress)
 897 {
 898         struct extent_map *em;
 899         int ret = 1;
 900         bool next_mergeable = true;
 901
 902         /*
 903          * make sure that once we start defragging an extent, we keep on
 904          * defragging it
 905          */
 906         if (start < *defrag_end)
 907                 return 1;
 908
 909         *skip = 0;
 910
 911         em = defrag_lookup_extent(inode, start);
 912         if (!em)
 913                 return 0;
 914
 915         /* this will cover holes, and inline extents */
 916         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
 917                 ret = 0;
 918                 goto out;
 919         }
 920
 921         next_mergeable = defrag_check_next_extent(inode, em);
 922
 923         /*
 924          * we hit a real extent, if it is big or the next extent is not a
 925          * real extent, don't bother defragging it
 926          */
 927         if (!compress && (*last_len == 0 || *last_len >= thresh) &&
 928             (em->len >= thresh || !next_mergeable))
 929                 ret = 0;
 930 out:
 931         /*
 932          * last_len ends up being a counter of how many bytes we've defragged.
 933          * every time we choose not to defrag an extent, we reset *last_len
 934          * so that the next tiny extent will force a defrag.
 935          *
 936          * The end result of this is that tiny extents before a single big
 937          * extent will force at least part of that big extent to be defragged.
 938          */
 939         if (ret) {
 940                 *defrag_end = extent_map_end(em);
 941         } else {
 942                 *last_len = 0;
 943                 *skip = extent_map_end(em);
 944                 *defrag_end = 0;
 945         }
 946
 947         free_extent_map(em);
 948         return ret;
 949 }
 950
 951 /*
 952  * it doesn't do much good to defrag one or two pages
 953  * at a time.  This pulls in a nice chunk of pages
 954  * to COW and defrag.
 955  *
 956  * It also makes sure the delalloc code has enough
 957  * dirty data to avoid making new small extents as part
 958  * of the defrag
 959  *
 960  * It's a good idea to start RA on this range
 961  * before calling this.
 962  */
 963 static int cluster_pages_for_defrag(struct inode *inode,
 964                                     struct page **pages,
 965                                     unsigned long start_index,
 966                                     int num_pages)
 967 {
 968         unsigned long file_end;
 969         u64 isize = i_size_read(inode);
 970         u64 page_start;
 971         u64 page_end;
 972         u64 page_cnt;
 973         int ret;
 974         int i;
 975         int i_done;
 976         struct btrfs_ordered_extent *ordered;
 977         struct extent_state *cached_state = NULL;
 978         struct extent_io_tree *tree;
 979         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
 980
 981         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
 982         if (!isize || start_index > file_end)
 983                 return 0;
 984
 985         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
 986
 987         ret = btrfs_delalloc_reserve_space(inode,
 988                                            page_cnt << PAGE_CACHE_SHIFT);
 989         if (ret)
 990                 return ret;
 991         i_done = 0;
 992         tree = &BTRFS_I(inode)->io_tree;
 993
 994         /* step one, lock all the pages */
 995         for (i = 0; i < page_cnt; i++) {
 996                 struct page *page;
 997 again:
 998                 page = find_or_create_page(inode->i_mapping,
 999                                            start_index + i, mask);
1000                 if (!page)
1001                         break;
1002
1003                 page_start = page_offset(page);
1004                 page_end = page_start + PAGE_CACHE_SIZE - 1;
1005                 while (1) {
1006                         lock_extent(tree, page_start, page_end);
1007                         ordered = btrfs_lookup_ordered_extent(inode,
1008                                                               page_start);
1009                         unlock_extent(tree, page_start, page_end);
1010                         if (!ordered)
1011                                 break;
1012
1013                         unlock_page(page);
1014                         btrfs_start_ordered_extent(inode, ordered, 1);
1015                         btrfs_put_ordered_extent(ordered);
1016                         lock_page(page);
1017                         /*
1018                          * we unlocked the page above, so we need check if
1019                          * it was released or not.
1020                          */
1021                         if (page->mapping != inode->i_mapping) {
1022                                 unlock_page(page);
1023                                 page_cache_release(page);
1024                                 goto again;
1025                         }
1026                 }
1027
1028                 if (!PageUptodate(page)) {
1029                         btrfs_readpage(NULL, page);
1030                         lock_page(page);
1031                         if (!PageUptodate(page)) {
1032                                 unlock_page(page);
1033                                 page_cache_release(page);
1034                                 ret = -EIO;
1035                                 break;
1036                         }
1037                 }
1038
1039                 if (page->mapping != inode->i_mapping) {
1040                         unlock_page(page);
1041                         page_cache_release(page);
1042                         goto again;
1043                 }
1044
1045                 pages[i] = page;
1046                 i_done++;
1047         }
1048         if (!i_done || ret)
1049                 goto out;
1050
1051         if (!(inode->i_sb->s_flags & MS_ACTIVE))
1052                 goto out;
1053
1054         /*
1055          * so now we have a nice long stream of locked
1056          * and up to date pages, lets wait on them
1057          */
1058         for (i = 0; i < i_done; i++)
1059                 wait_on_page_writeback(pages[i]);
1060
1061         page_start = page_offset(pages[0]);
1062         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1063
1064         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1065                          page_start, page_end - 1, 0, &cached_state);
1066         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1067                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1068                           EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1069                           &cached_state, GFP_NOFS);
1070
1071         if (i_done != page_cnt) {
1072                 spin_lock(&BTRFS_I(inode)->lock);
1073                 BTRFS_I(inode)->outstanding_extents++;
1074                 spin_unlock(&BTRFS_I(inode)->lock);
1075                 btrfs_delalloc_release_space(inode,
1076                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1077         }
1078
1079
1080         set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1081                           &cached_state, GFP_NOFS);
1082
1083         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1084                              page_start, page_end - 1, &cached_state,
1085                              GFP_NOFS);
1086
1087         for (i = 0; i < i_done; i++) {
1088                 clear_page_dirty_for_io(pages[i]);
1089                 ClearPageChecked(pages[i]);
1090                 set_page_extent_mapped(pages[i]);
1091                 set_page_dirty(pages[i]);
1092                 unlock_page(pages[i]);
1093                 page_cache_release(pages[i]);
1094         }
1095         return i_done;
1096 out:
1097         for (i = 0; i < i_done; i++) {
1098                 unlock_page(pages[i]);
1099                 page_cache_release(pages[i]);
1100         }
1101         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1102         return ret;
1103
1104 }
1105
1106 int btrfs_defrag_file(struct inode *inode, struct file *file,
1107                       struct btrfs_ioctl_defrag_range_args *range,
1108                       u64 newer_than, unsigned long max_to_defrag)
1109 {
1110         struct btrfs_root *root = BTRFS_I(inode)->root;
1111         struct file_ra_state *ra = NULL;
1112         unsigned long last_index;
1113         u64 isize = i_size_read(inode);
1114         u64 last_len = 0;
1115         u64 skip = 0;
1116         u64 defrag_end = 0;
1117         u64 newer_off = range->start;
1118         unsigned long i;
1119         unsigned long ra_index = 0;
1120         int ret;
1121         int defrag_count = 0;
1122         int compress_type = BTRFS_COMPRESS_ZLIB;
1123         int extent_thresh = range->extent_thresh;
1124         int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1125         int cluster = max_cluster;
1126         u64 new_align = ~((u64)128 * 1024 - 1);
1127         struct page **pages = NULL;
1128
1129         if (extent_thresh == 0)
1130                 extent_thresh = 256 * 1024;
1131
1132         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1133                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1134                         return -EINVAL;
1135                 if (range->compress_type)
1136                         compress_type = range->compress_type;
1137         }
1138
1139         if (isize == 0)
1140                 return 0;
1141
1142         /*
1143          * if we were not given a file, allocate a readahead
1144          * context
1145          */
1146         if (!file) {
1147                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1148                 if (!ra)
1149                         return -ENOMEM;
1150                 file_ra_state_init(ra, inode->i_mapping);
1151         } else {
1152                 ra = &file->f_ra;
1153         }
1154
1155         pages = kmalloc(sizeof(struct page *) * max_cluster,
1156                         GFP_NOFS);
1157         if (!pages) {
1158                 ret = -ENOMEM;
1159                 goto out_ra;
1160         }
1161
1162         /* find the last page to defrag */
1163         if (range->start + range->len > range->start) {
1164                 last_index = min_t(u64, isize - 1,
1165                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1166         } else {
1167                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1168         }
1169
1170         if (newer_than) {
1171                 ret = find_new_extents(root, inode, newer_than,
1172                                        &newer_off, 64 * 1024);
1173                 if (!ret) {
1174                         range->start = newer_off;
1175                         /*
1176                          * we always align our defrag to help keep
1177                          * the extents in the file evenly spaced
1178                          */
1179                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1180                 } else
1181                         goto out_ra;
1182         } else {
1183                 i = range->start >> PAGE_CACHE_SHIFT;
1184         }
1185         if (!max_to_defrag)
1186                 max_to_defrag = last_index + 1;
1187
1188         /*
1189          * make writeback starts from i, so the defrag range can be
1190          * written sequentially.
1191          */
1192         if (i < inode->i_mapping->writeback_index)
1193                 inode->i_mapping->writeback_index = i;
1194
1195         while (i <= last_index && defrag_count < max_to_defrag &&
1196                (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1197                 PAGE_CACHE_SHIFT)) {
1198                 /*
1199                  * make sure we stop running if someone unmounts
1200                  * the FS
1201                  */
1202                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1203                         break;
1204
1205                 if (btrfs_defrag_cancelled(root->fs_info)) {
1206                         printk(KERN_DEBUG "btrfs: defrag_file cancelled\n");
1207                         ret = -EAGAIN;
1208                         break;
1209                 }
1210
1211                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1212                                          extent_thresh, &last_len, &skip,
1213                                          &defrag_end, range->flags &
1214                                          BTRFS_DEFRAG_RANGE_COMPRESS)) {
1215                         unsigned long next;
1216                         /*
1217                          * the should_defrag function tells us how much to skip
1218                          * bump our counter by the suggested amount
1219                          */
1220                         next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1221                         i = max(i + 1, next);
1222                         continue;
1223                 }
1224
1225                 if (!newer_than) {
1226                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1227                                    PAGE_CACHE_SHIFT) - i;
1228                         cluster = min(cluster, max_cluster);
1229                 } else {
1230                         cluster = max_cluster;
1231                 }
1232
1233                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1234                         BTRFS_I(inode)->force_compress = compress_type;
1235
1236                 if (i + cluster > ra_index) {
1237                         ra_index = max(i, ra_index);
1238                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1239                                        cluster);
1240                         ra_index += max_cluster;
1241                 }
1242
1243                 mutex_lock(&inode->i_mutex);
1244                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1245                 if (ret < 0) {
1246                         mutex_unlock(&inode->i_mutex);
1247                         goto out_ra;
1248                 }
1249
1250                 defrag_count += ret;
1251                 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1252                 mutex_unlock(&inode->i_mutex);
1253
1254                 if (newer_than) {
1255                         if (newer_off == (u64)-1)
1256                                 break;
1257
1258                         if (ret > 0)
1259                                 i += ret;
1260
1261                         newer_off = max(newer_off + 1,
1262                                         (u64)i << PAGE_CACHE_SHIFT);
1263
1264                         ret = find_new_extents(root, inode,
1265                                                newer_than, &newer_off,
1266                                                64 * 1024);
1267                         if (!ret) {
1268                                 range->start = newer_off;
1269                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1270                         } else {
1271                                 break;
1272                         }
1273                 } else {
1274                         if (ret > 0) {
1275                                 i += ret;
1276                                 last_len += ret << PAGE_CACHE_SHIFT;
1277                         } else {
1278                                 i++;
1279                                 last_len = 0;
1280                         }
1281                 }
1282         }
1283
1284         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1285                 filemap_flush(inode->i_mapping);
1286
1287         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1288                 /* the filemap_flush will queue IO into the worker threads, but
1289                  * we have to make sure the IO is actually started and that
1290                  * ordered extents get created before we return
1291                  */
1292                 atomic_inc(&root->fs_info->async_submit_draining);
1293                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1294                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1295                         wait_event(root->fs_info->async_submit_wait,
1296                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1297                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1298                 }
1299                 atomic_dec(&root->fs_info->async_submit_draining);
1300
1301                 mutex_lock(&inode->i_mutex);
1302                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1303                 mutex_unlock(&inode->i_mutex);
1304         }
1305
1306         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1307                 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1308         }
1309
1310         ret = defrag_count;
1311
1312 out_ra:
1313         if (!file)
1314                 kfree(ra);
1315         kfree(pages);
1316         return ret;
1317 }
1318
1319 static noinline int btrfs_ioctl_resize(struct file *file,
1320                                         void __user *arg)
1321 {
1322         u64 new_size;
1323         u64 old_size;
1324         u64 devid = 1;
1325         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1326         struct btrfs_ioctl_vol_args *vol_args;
1327         struct btrfs_trans_handle *trans;
1328         struct btrfs_device *device = NULL;
1329         char *sizestr;
1330         char *devstr = NULL;
1331         int ret = 0;
1332         int mod = 0;
1333
1334         if (!capable(CAP_SYS_ADMIN))
1335                 return -EPERM;
1336
1337         ret = mnt_want_write_file(file);
1338         if (ret)
1339                 return ret;
1340
1341         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1342                         1)) {
1343                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
1344                 mnt_drop_write_file(file);
1345                 return -EINVAL;
1346         }
1347
1348         mutex_lock(&root->fs_info->volume_mutex);
1349         vol_args = memdup_user(arg, sizeof(*vol_args));
1350         if (IS_ERR(vol_args)) {
1351                 ret = PTR_ERR(vol_args);
1352                 goto out;
1353         }
1354
1355         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1356
1357         sizestr = vol_args->name;
1358         devstr = strchr(sizestr, ':');
1359         if (devstr) {
1360                 char *end;
1361                 sizestr = devstr + 1;
1362                 *devstr = '\0';
1363                 devstr = vol_args->name;
1364                 devid = simple_strtoull(devstr, &end, 10);
1365                 if (!devid) {
1366                         ret = -EINVAL;
1367                         goto out_free;
1368                 }
1369                 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1370                        (unsigned long long)devid);
1371         }
1372
1373         device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1374         if (!device) {
1375                 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1376                        (unsigned long long)devid);
1377                 ret = -ENODEV;
1378                 goto out_free;
1379         }
1380
1381         if (!device->writeable) {
1382                 printk(KERN_INFO "btrfs: resizer unable to apply on "
1383                        "readonly device %llu\n",
1384                        (unsigned long long)devid);
1385                 ret = -EPERM;
1386                 goto out_free;
1387         }
1388
1389         if (!strcmp(sizestr, "max"))
1390                 new_size = device->bdev->bd_inode->i_size;
1391         else {
1392                 if (sizestr[0] == '-') {
1393                         mod = -1;
1394                         sizestr++;
1395                 } else if (sizestr[0] == '+') {
1396                         mod = 1;
1397                         sizestr++;
1398                 }
1399                 new_size = memparse(sizestr, NULL);
1400                 if (new_size == 0) {
1401                         ret = -EINVAL;
1402                         goto out_free;
1403                 }
1404         }
1405
1406         if (device->is_tgtdev_for_dev_replace) {
1407                 ret = -EPERM;
1408                 goto out_free;
1409         }
1410
1411         old_size = device->total_bytes;
1412
1413         if (mod < 0) {
1414                 if (new_size > old_size) {
1415                         ret = -EINVAL;
1416                         goto out_free;
1417                 }
1418                 new_size = old_size - new_size;
1419         } else if (mod > 0) {
1420                 new_size = old_size + new_size;
1421         }
1422
1423         if (new_size < 256 * 1024 * 1024) {
1424                 ret = -EINVAL;
1425                 goto out_free;
1426         }
1427         if (new_size > device->bdev->bd_inode->i_size) {
1428                 ret = -EFBIG;
1429                 goto out_free;
1430         }
1431
1432         do_div(new_size, root->sectorsize);
1433         new_size *= root->sectorsize;
1434
1435         printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1436                       rcu_str_deref(device->name),
1437                       (unsigned long long)new_size);
1438
1439         if (new_size > old_size) {
1440                 trans = btrfs_start_transaction(root, 0);
1441                 if (IS_ERR(trans)) {
1442                         ret = PTR_ERR(trans);
1443                         goto out_free;
1444                 }
1445                 ret = btrfs_grow_device(trans, device, new_size);
1446                 btrfs_commit_transaction(trans, root);
1447         } else if (new_size < old_size) {
1448                 ret = btrfs_shrink_device(device, new_size);
1449         } /* equal, nothing need to do */
1450
1451 out_free:
1452         kfree(vol_args);
1453 out:
1454         mutex_unlock(&root->fs_info->volume_mutex);
1455         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1456         mnt_drop_write_file(file);
1457         return ret;
1458 }
1459
1460 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1461                                 char *name, unsigned long fd, int subvol,
1462                                 u64 *transid, bool readonly,
1463                                 struct btrfs_qgroup_inherit *inherit)
1464 {
1465         int namelen;
1466         int ret = 0;
1467
1468         ret = mnt_want_write_file(file);
1469         if (ret)
1470                 goto out;
1471
1472         namelen = strlen(name);
1473         if (strchr(name, '/')) {
1474                 ret = -EINVAL;
1475                 goto out_drop_write;
1476         }
1477
1478         if (name[0] == '.' &&
1479            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1480                 ret = -EEXIST;
1481                 goto out_drop_write;
1482         }
1483
1484         if (subvol) {
1485                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1486                                      NULL, transid, readonly, inherit);
1487         } else {
1488                 struct fd src = fdget(fd);
1489                 struct inode *src_inode;
1490                 if (!src.file) {
1491                         ret = -EINVAL;
1492                         goto out_drop_write;
1493                 }
1494
1495                 src_inode = src.file->f_path.dentry->d_inode;
1496                 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1497                         printk(KERN_INFO "btrfs: Snapshot src from "
1498                                "another FS\n");
1499                         ret = -EINVAL;
1500                 } else {
1501                         ret = btrfs_mksubvol(&file->f_path, name, namelen,
1502                                              BTRFS_I(src_inode)->root,
1503                                              transid, readonly, inherit);
1504                 }
1505                 fdput(src);
1506         }
1507 out_drop_write:
1508         mnt_drop_write_file(file);
1509 out:
1510         return ret;
1511 }
1512
1513 static noinline int btrfs_ioctl_snap_create(struct file *file,
1514                                             void __user *arg, int subvol)
1515 {
1516         struct btrfs_ioctl_vol_args *vol_args;
1517         int ret;
1518
1519         vol_args = memdup_user(arg, sizeof(*vol_args));
1520         if (IS_ERR(vol_args))
1521                 return PTR_ERR(vol_args);
1522         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1523
1524         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1525                                               vol_args->fd, subvol,
1526                                               NULL, false, NULL);
1527
1528         kfree(vol_args);
1529         return ret;
1530 }
1531
1532 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1533                                                void __user *arg, int subvol)
1534 {
1535         struct btrfs_ioctl_vol_args_v2 *vol_args;
1536         int ret;
1537         u64 transid = 0;
1538         u64 *ptr = NULL;
1539         bool readonly = false;
1540         struct btrfs_qgroup_inherit *inherit = NULL;
1541
1542         vol_args = memdup_user(arg, sizeof(*vol_args));
1543         if (IS_ERR(vol_args))
1544                 return PTR_ERR(vol_args);
1545         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1546
1547         if (vol_args->flags &
1548             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1549               BTRFS_SUBVOL_QGROUP_INHERIT)) {
1550                 ret = -EOPNOTSUPP;
1551                 goto out;
1552         }
1553
1554         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1555                 ptr = &transid;
1556         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1557                 readonly = true;
1558         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1559                 if (vol_args->size > PAGE_CACHE_SIZE) {
1560                         ret = -EINVAL;
1561                         goto out;
1562                 }
1563                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1564                 if (IS_ERR(inherit)) {
1565                         ret = PTR_ERR(inherit);
1566                         goto out;
1567                 }
1568         }
1569
1570         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1571                                               vol_args->fd, subvol, ptr,
1572                                               readonly, inherit);
1573
1574         if (ret == 0 && ptr &&
1575             copy_to_user(arg +
1576                          offsetof(struct btrfs_ioctl_vol_args_v2,
1577                                   transid), ptr, sizeof(*ptr)))
1578                 ret = -EFAULT;
1579 out:
1580         kfree(vol_args);
1581         kfree(inherit);
1582         return ret;
1583 }
1584
1585 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1586                                                 void __user *arg)
1587 {
1588         struct inode *inode = fdentry(file)->d_inode;
1589         struct btrfs_root *root = BTRFS_I(inode)->root;
1590         int ret = 0;
1591         u64 flags = 0;
1592
1593         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1594                 return -EINVAL;
1595
1596         down_read(&root->fs_info->subvol_sem);
1597         if (btrfs_root_readonly(root))
1598                 flags |= BTRFS_SUBVOL_RDONLY;
1599         up_read(&root->fs_info->subvol_sem);
1600
1601         if (copy_to_user(arg, &flags, sizeof(flags)))
1602                 ret = -EFAULT;
1603
1604         return ret;
1605 }
1606
1607 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1608                                               void __user *arg)
1609 {
1610         struct inode *inode = fdentry(file)->d_inode;
1611         struct btrfs_root *root = BTRFS_I(inode)->root;
1612         struct btrfs_trans_handle *trans;
1613         u64 root_flags;
1614         u64 flags;
1615         int ret = 0;
1616
1617         ret = mnt_want_write_file(file);
1618         if (ret)
1619                 goto out;
1620
1621         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1622                 ret = -EINVAL;
1623                 goto out_drop_write;
1624         }
1625
1626         if (copy_from_user(&flags, arg, sizeof(flags))) {
1627                 ret = -EFAULT;
1628                 goto out_drop_write;
1629         }
1630
1631         if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1632                 ret = -EINVAL;
1633                 goto out_drop_write;
1634         }
1635
1636         if (flags & ~BTRFS_SUBVOL_RDONLY) {
1637                 ret = -EOPNOTSUPP;
1638                 goto out_drop_write;
1639         }
1640
1641         if (!inode_owner_or_capable(inode)) {
1642                 ret = -EACCES;
1643                 goto out_drop_write;
1644         }
1645
1646         down_write(&root->fs_info->subvol_sem);
1647
1648         /* nothing to do */
1649         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1650                 goto out_drop_sem;
1651
1652         root_flags = btrfs_root_flags(&root->root_item);
1653         if (flags & BTRFS_SUBVOL_RDONLY)
1654                 btrfs_set_root_flags(&root->root_item,
1655                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1656         else
1657                 btrfs_set_root_flags(&root->root_item,
1658                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1659
1660         trans = btrfs_start_transaction(root, 1);
1661         if (IS_ERR(trans)) {
1662                 ret = PTR_ERR(trans);
1663                 goto out_reset;
1664         }
1665
1666         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1667                                 &root->root_key, &root->root_item);
1668
1669         btrfs_commit_transaction(trans, root);
1670 out_reset:
1671         if (ret)
1672                 btrfs_set_root_flags(&root->root_item, root_flags);
1673 out_drop_sem:
1674         up_write(&root->fs_info->subvol_sem);
1675 out_drop_write:
1676         mnt_drop_write_file(file);
1677 out:
1678         return ret;
1679 }
1680
1681 /*
1682  * helper to check if the subvolume references other subvolumes
1683  */
1684 static noinline int may_destroy_subvol(struct btrfs_root *root)
1685 {
1686         struct btrfs_path *path;
1687         struct btrfs_key key;
1688         int ret;
1689
1690         path = btrfs_alloc_path();
1691         if (!path)
1692                 return -ENOMEM;
1693
1694         key.objectid = root->root_key.objectid;
1695         key.type = BTRFS_ROOT_REF_KEY;
1696         key.offset = (u64)-1;
1697
1698         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1699                                 &key, path, 0, 0);
1700         if (ret < 0)
1701                 goto out;
1702         BUG_ON(ret == 0);
1703
1704         ret = 0;
1705         if (path->slots[0] > 0) {
1706                 path->slots[0]--;
1707                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1708                 if (key.objectid == root->root_key.objectid &&
1709                     key.type == BTRFS_ROOT_REF_KEY)
1710                         ret = -ENOTEMPTY;
1711         }
1712 out:
1713         btrfs_free_path(path);
1714         return ret;
1715 }
1716
1717 static noinline int key_in_sk(struct btrfs_key *key,
1718                               struct btrfs_ioctl_search_key *sk)
1719 {
1720         struct btrfs_key test;
1721         int ret;
1722
1723         test.objectid = sk->min_objectid;
1724         test.type = sk->min_type;
1725         test.offset = sk->min_offset;
1726
1727         ret = btrfs_comp_cpu_keys(key, &test);
1728         if (ret < 0)
1729                 return 0;
1730
1731         test.objectid = sk->max_objectid;
1732         test.type = sk->max_type;
1733         test.offset = sk->max_offset;
1734
1735         ret = btrfs_comp_cpu_keys(key, &test);
1736         if (ret > 0)
1737                 return 0;
1738         return 1;
1739 }
1740
1741 static noinline int copy_to_sk(struct btrfs_root *root,
1742                                struct btrfs_path *path,
1743                                struct btrfs_key *key,
1744                                struct btrfs_ioctl_search_key *sk,
1745                                char *buf,
1746                                unsigned long *sk_offset,
1747                                int *num_found)
1748 {
1749         u64 found_transid;
1750         struct extent_buffer *leaf;
1751         struct btrfs_ioctl_search_header sh;
1752         unsigned long item_off;
1753         unsigned long item_len;
1754         int nritems;
1755         int i;
1756         int slot;
1757         int ret = 0;
1758
1759         leaf = path->nodes[0];
1760         slot = path->slots[0];
1761         nritems = btrfs_header_nritems(leaf);
1762
1763         if (btrfs_header_generation(leaf) > sk->max_transid) {
1764                 i = nritems;
1765                 goto advance_key;
1766         }
1767         found_transid = btrfs_header_generation(leaf);
1768
1769         for (i = slot; i < nritems; i++) {
1770                 item_off = btrfs_item_ptr_offset(leaf, i);
1771                 item_len = btrfs_item_size_nr(leaf, i);
1772
1773                 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1774                         item_len = 0;
1775
1776                 if (sizeof(sh) + item_len + *sk_offset >
1777                     BTRFS_SEARCH_ARGS_BUFSIZE) {
1778                         ret = 1;
1779                         goto overflow;
1780                 }
1781
1782                 btrfs_item_key_to_cpu(leaf, key, i);
1783                 if (!key_in_sk(key, sk))
1784                         continue;
1785
1786                 sh.objectid = key->objectid;
1787                 sh.offset = key->offset;
1788                 sh.type = key->type;
1789                 sh.len = item_len;
1790                 sh.transid = found_transid;
1791
1792                 /* copy search result header */
1793                 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1794                 *sk_offset += sizeof(sh);
1795
1796                 if (item_len) {
1797                         char *p = buf + *sk_offset;
1798                         /* copy the item */
1799                         read_extent_buffer(leaf, p,
1800                                            item_off, item_len);
1801                         *sk_offset += item_len;
1802                 }
1803                 (*num_found)++;
1804
1805                 if (*num_found >= sk->nr_items)
1806                         break;
1807         }
1808 advance_key:
1809         ret = 0;
1810         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1811                 key->offset++;
1812         else if (key->type < (u8)-1 && key->type < sk->max_type) {
1813                 key->offset = 0;
1814                 key->type++;
1815         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1816                 key->offset = 0;
1817                 key->type = 0;
1818                 key->objectid++;
1819         } else
1820                 ret = 1;
1821 overflow:
1822         return ret;
1823 }
1824
1825 static noinline int search_ioctl(struct inode *inode,
1826                                  struct btrfs_ioctl_search_args *args)
1827 {
1828         struct btrfs_root *root;
1829         struct btrfs_key key;
1830         struct btrfs_key max_key;
1831         struct btrfs_path *path;
1832         struct btrfs_ioctl_search_key *sk = &args->key;
1833         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1834         int ret;
1835         int num_found = 0;
1836         unsigned long sk_offset = 0;
1837
1838         path = btrfs_alloc_path();
1839         if (!path)
1840                 return -ENOMEM;
1841
1842         if (sk->tree_id == 0) {
1843                 /* search the root of the inode that was passed */
1844                 root = BTRFS_I(inode)->root;
1845         } else {
1846                 key.objectid = sk->tree_id;
1847                 key.type = BTRFS_ROOT_ITEM_KEY;
1848                 key.offset = (u64)-1;
1849                 root = btrfs_read_fs_root_no_name(info, &key);
1850                 if (IS_ERR(root)) {
1851                         printk(KERN_ERR "could not find root %llu\n",
1852                                sk->tree_id);
1853                         btrfs_free_path(path);
1854                         return -ENOENT;
1855                 }
1856         }
1857
1858         key.objectid = sk->min_objectid;
1859         key.type = sk->min_type;
1860         key.offset = sk->min_offset;
1861
1862         max_key.objectid = sk->max_objectid;
1863         max_key.type = sk->max_type;
1864         max_key.offset = sk->max_offset;
1865
1866         path->keep_locks = 1;
1867
1868         while(1) {
1869                 ret = btrfs_search_forward(root, &key, &max_key, path,
1870                                            sk->min_transid);
1871                 if (ret != 0) {
1872                         if (ret > 0)
1873                                 ret = 0;
1874                         goto err;
1875                 }
1876                 ret = copy_to_sk(root, path, &key, sk, args->buf,
1877                                  &sk_offset, &num_found);
1878                 btrfs_release_path(path);
1879                 if (ret || num_found >= sk->nr_items)
1880                         break;
1881
1882         }
1883         ret = 0;
1884 err:
1885         sk->nr_items = num_found;
1886         btrfs_free_path(path);
1887         return ret;
1888 }
1889
1890 static noinline int btrfs_ioctl_tree_search(struct file *file,
1891                                            void __user *argp)
1892 {
1893          struct btrfs_ioctl_search_args *args;
1894          struct inode *inode;
1895          int ret;
1896
1897         if (!capable(CAP_SYS_ADMIN))
1898                 return -EPERM;
1899
1900         args = memdup_user(argp, sizeof(*args));
1901         if (IS_ERR(args))
1902                 return PTR_ERR(args);
1903
1904         inode = fdentry(file)->d_inode;
1905         ret = search_ioctl(inode, args);
1906         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1907                 ret = -EFAULT;
1908         kfree(args);
1909         return ret;
1910 }
1911
1912 /*
1913  * Search INODE_REFs to identify path name of 'dirid' directory
1914  * in a 'tree_id' tree. and sets path name to 'name'.
1915  */
1916 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1917                                 u64 tree_id, u64 dirid, char *name)
1918 {
1919         struct btrfs_root *root;
1920         struct btrfs_key key;
1921         char *ptr;
1922         int ret = -1;
1923         int slot;
1924         int len;
1925         int total_len = 0;
1926         struct btrfs_inode_ref *iref;
1927         struct extent_buffer *l;
1928         struct btrfs_path *path;
1929
1930         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1931                 name[0]='\0';
1932                 return 0;
1933         }
1934
1935         path = btrfs_alloc_path();
1936         if (!path)
1937                 return -ENOMEM;
1938
1939         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1940
1941         key.objectid = tree_id;
1942         key.type = BTRFS_ROOT_ITEM_KEY;
1943         key.offset = (u64)-1;
1944         root = btrfs_read_fs_root_no_name(info, &key);
1945         if (IS_ERR(root)) {
1946                 printk(KERN_ERR "could not find root %llu\n", tree_id);
1947                 ret = -ENOENT;
1948                 goto out;
1949         }
1950
1951         key.objectid = dirid;
1952         key.type = BTRFS_INODE_REF_KEY;
1953         key.offset = (u64)-1;
1954
1955         while(1) {
1956                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1957                 if (ret < 0)
1958                         goto out;
1959
1960                 l = path->nodes[0];
1961                 slot = path->slots[0];
1962                 if (ret > 0 && slot > 0)
1963                         slot--;
1964                 btrfs_item_key_to_cpu(l, &key, slot);
1965
1966                 if (ret > 0 && (key.objectid != dirid ||
1967                                 key.type != BTRFS_INODE_REF_KEY)) {
1968                         ret = -ENOENT;
1969                         goto out;
1970                 }
1971
1972                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1973                 len = btrfs_inode_ref_name_len(l, iref);
1974                 ptr -= len + 1;
1975                 total_len += len + 1;
1976                 if (ptr < name)
1977                         goto out;
1978
1979                 *(ptr + len) = '/';
1980                 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1981
1982                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1983                         break;
1984
1985                 btrfs_release_path(path);
1986                 key.objectid = key.offset;
1987                 key.offset = (u64)-1;
1988                 dirid = key.objectid;
1989         }
1990         if (ptr < name)
1991                 goto out;
1992         memmove(name, ptr, total_len);
1993         name[total_len]='\0';
1994         ret = 0;
1995 out:
1996         btrfs_free_path(path);
1997         return ret;
1998 }
1999
2000 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2001                                            void __user *argp)
2002 {
2003          struct btrfs_ioctl_ino_lookup_args *args;
2004          struct inode *inode;
2005          int ret;
2006
2007         if (!capable(CAP_SYS_ADMIN))
2008                 return -EPERM;
2009
2010         args = memdup_user(argp, sizeof(*args));
2011         if (IS_ERR(args))
2012                 return PTR_ERR(args);
2013
2014         inode = fdentry(file)->d_inode;
2015
2016         if (args->treeid == 0)
2017                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2018
2019         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2020                                         args->treeid, args->objectid,
2021                                         args->name);
2022
2023         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2024                 ret = -EFAULT;
2025
2026         kfree(args);
2027         return ret;
2028 }
2029
2030 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2031                                              void __user *arg)
2032 {
2033         struct dentry *parent = fdentry(file);
2034         struct dentry *dentry;
2035         struct inode *dir = parent->d_inode;
2036         struct inode *inode;
2037         struct btrfs_root *root = BTRFS_I(dir)->root;
2038         struct btrfs_root *dest = NULL;
2039         struct btrfs_ioctl_vol_args *vol_args;
2040         struct btrfs_trans_handle *trans;
2041         int namelen;
2042         int ret;
2043         int err = 0;
2044
2045         vol_args = memdup_user(arg, sizeof(*vol_args));
2046         if (IS_ERR(vol_args))
2047                 return PTR_ERR(vol_args);
2048
2049         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2050         namelen = strlen(vol_args->name);
2051         if (strchr(vol_args->name, '/') ||
2052             strncmp(vol_args->name, "..", namelen) == 0) {
2053                 err = -EINVAL;
2054                 goto out;
2055         }
2056
2057         err = mnt_want_write_file(file);
2058         if (err)
2059                 goto out;
2060
2061         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
2062         dentry = lookup_one_len(vol_args->name, parent, namelen);
2063         if (IS_ERR(dentry)) {
2064                 err = PTR_ERR(dentry);
2065                 goto out_unlock_dir;
2066         }
2067
2068         if (!dentry->d_inode) {
2069                 err = -ENOENT;
2070                 goto out_dput;
2071         }
2072
2073         inode = dentry->d_inode;
2074         dest = BTRFS_I(inode)->root;
2075         if (!capable(CAP_SYS_ADMIN)){
2076                 /*
2077                  * Regular user.  Only allow this with a special mount
2078                  * option, when the user has write+exec access to the
2079                  * subvol root, and when rmdir(2) would have been
2080                  * allowed.
2081                  *
2082                  * Note that this is _not_ check that the subvol is
2083                  * empty or doesn't contain data that we wouldn't
2084                  * otherwise be able to delete.
2085                  *
2086                  * Users who want to delete empty subvols should try
2087                  * rmdir(2).
2088                  */
2089                 err = -EPERM;
2090                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2091                         goto out_dput;
2092
2093                 /*
2094                  * Do not allow deletion if the parent dir is the same
2095                  * as the dir to be deleted.  That means the ioctl
2096                  * must be called on the dentry referencing the root
2097                  * of the subvol, not a random directory contained
2098                  * within it.
2099                  */
2100                 err = -EINVAL;
2101                 if (root == dest)
2102                         goto out_dput;
2103
2104                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2105                 if (err)
2106                         goto out_dput;
2107         }
2108
2109         /* check if subvolume may be deleted by a user */
2110         err = btrfs_may_delete(dir, dentry, 1);
2111         if (err)
2112                 goto out_dput;
2113
2114         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2115                 err = -EINVAL;
2116                 goto out_dput;
2117         }
2118
2119         mutex_lock(&inode->i_mutex);
2120         err = d_invalidate(dentry);
2121         if (err)
2122                 goto out_unlock;
2123
2124         down_write(&root->fs_info->subvol_sem);
2125
2126         err = may_destroy_subvol(dest);
2127         if (err)
2128                 goto out_up_write;
2129
2130         trans = btrfs_start_transaction(root, 0);
2131         if (IS_ERR(trans)) {
2132                 err = PTR_ERR(trans);
2133                 goto out_up_write;
2134         }
2135         trans->block_rsv = &root->fs_info->global_block_rsv;
2136
2137         ret = btrfs_unlink_subvol(trans, root, dir,
2138                                 dest->root_key.objectid,
2139                                 dentry->d_name.name,
2140                                 dentry->d_name.len);
2141         if (ret) {
2142                 err = ret;
2143                 btrfs_abort_transaction(trans, root, ret);
2144                 goto out_end_trans;
2145         }
2146
2147         btrfs_record_root_in_trans(trans, dest);
2148
2149         memset(&dest->root_item.drop_progress, 0,
2150                 sizeof(dest->root_item.drop_progress));
2151         dest->root_item.drop_level = 0;
2152         btrfs_set_root_refs(&dest->root_item, 0);
2153
2154         if (!xchg(&dest->orphan_item_inserted, 1)) {
2155                 ret = btrfs_insert_orphan_item(trans,
2156                                         root->fs_info->tree_root,
2157                                         dest->root_key.objectid);
2158                 if (ret) {
2159                         btrfs_abort_transaction(trans, root, ret);
2160                         err = ret;
2161                         goto out_end_trans;
2162                 }
2163         }
2164 out_end_trans:
2165         ret = btrfs_end_transaction(trans, root);
2166         if (ret && !err)
2167                 err = ret;
2168         inode->i_flags |= S_DEAD;
2169 out_up_write:
2170         up_write(&root->fs_info->subvol_sem);
2171 out_unlock:
2172         mutex_unlock(&inode->i_mutex);
2173         if (!err) {
2174                 shrink_dcache_sb(root->fs_info->sb);
2175                 btrfs_invalidate_inodes(dest);
2176                 d_delete(dentry);
2177         }
2178 out_dput:
2179         dput(dentry);
2180 out_unlock_dir:
2181         mutex_unlock(&dir->i_mutex);
2182         mnt_drop_write_file(file);
2183 out:
2184         kfree(vol_args);
2185         return err;
2186 }
2187
2188 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2189 {
2190         struct inode *inode = fdentry(file)->d_inode;
2191         struct btrfs_root *root = BTRFS_I(inode)->root;
2192         struct btrfs_ioctl_defrag_range_args *range;
2193         int ret;
2194
2195         ret = mnt_want_write_file(file);
2196         if (ret)
2197                 return ret;
2198
2199         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2200                         1)) {
2201                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2202                 mnt_drop_write_file(file);
2203                 return -EINVAL;
2204         }
2205
2206         if (btrfs_root_readonly(root)) {
2207                 ret = -EROFS;
2208                 goto out;
2209         }
2210
2211         switch (inode->i_mode & S_IFMT) {
2212         case S_IFDIR:
2213                 if (!capable(CAP_SYS_ADMIN)) {
2214                         ret = -EPERM;
2215                         goto out;
2216                 }
2217                 ret = btrfs_defrag_root(root);
2218                 if (ret)
2219                         goto out;
2220                 ret = btrfs_defrag_root(root->fs_info->extent_root);
2221                 break;
2222         case S_IFREG:
2223                 if (!(file->f_mode & FMODE_WRITE)) {
2224                         ret = -EINVAL;
2225                         goto out;
2226                 }
2227
2228                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2229                 if (!range) {
2230                         ret = -ENOMEM;
2231                         goto out;
2232                 }
2233
2234                 if (argp) {
2235                         if (copy_from_user(range, argp,
2236                                            sizeof(*range))) {
2237                                 ret = -EFAULT;
2238                                 kfree(range);
2239                                 goto out;
2240                         }
2241                         /* compression requires us to start the IO */
2242                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2243                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2244                                 range->extent_thresh = (u32)-1;
2245                         }
2246                 } else {
2247                         /* the rest are all set to zero by kzalloc */
2248                         range->len = (u64)-1;
2249                 }
2250                 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2251                                         range, 0, 0);
2252                 if (ret > 0)
2253                         ret = 0;
2254                 kfree(range);
2255                 break;
2256         default:
2257                 ret = -EINVAL;
2258         }
2259 out:
2260         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2261         mnt_drop_write_file(file);
2262         return ret;
2263 }
2264
2265 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2266 {
2267         struct btrfs_ioctl_vol_args *vol_args;
2268         int ret;
2269
2270         if (!capable(CAP_SYS_ADMIN))
2271                 return -EPERM;
2272
2273         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2274                         1)) {
2275                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2276                 return -EINVAL;
2277         }
2278
2279         mutex_lock(&root->fs_info->volume_mutex);
2280         vol_args = memdup_user(arg, sizeof(*vol_args));
2281         if (IS_ERR(vol_args)) {
2282                 ret = PTR_ERR(vol_args);
2283                 goto out;
2284         }
2285
2286         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2287         ret = btrfs_init_new_device(root, vol_args->name);
2288
2289         kfree(vol_args);
2290 out:
2291         mutex_unlock(&root->fs_info->volume_mutex);
2292         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2293         return ret;
2294 }
2295
2296 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2297 {
2298         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2299         struct btrfs_ioctl_vol_args *vol_args;
2300         int ret;
2301
2302         if (!capable(CAP_SYS_ADMIN))
2303                 return -EPERM;
2304
2305         ret = mnt_want_write_file(file);
2306         if (ret)
2307                 return ret;
2308
2309         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2310                         1)) {
2311                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2312                 mnt_drop_write_file(file);
2313                 return -EINVAL;
2314         }
2315
2316         mutex_lock(&root->fs_info->volume_mutex);
2317         vol_args = memdup_user(arg, sizeof(*vol_args));
2318         if (IS_ERR(vol_args)) {
2319                 ret = PTR_ERR(vol_args);
2320                 goto out;
2321         }
2322
2323         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2324         ret = btrfs_rm_device(root, vol_args->name);
2325
2326         kfree(vol_args);
2327 out:
2328         mutex_unlock(&root->fs_info->volume_mutex);
2329         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2330         mnt_drop_write_file(file);
2331         return ret;
2332 }
2333
2334 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2335 {
2336         struct btrfs_ioctl_fs_info_args *fi_args;
2337         struct btrfs_device *device;
2338         struct btrfs_device *next;
2339         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2340         int ret = 0;
2341
2342         if (!capable(CAP_SYS_ADMIN))
2343                 return -EPERM;
2344
2345         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2346         if (!fi_args)
2347                 return -ENOMEM;
2348
2349         fi_args->num_devices = fs_devices->num_devices;
2350         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2351
2352         mutex_lock(&fs_devices->device_list_mutex);
2353         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2354                 if (device->devid > fi_args->max_id)
2355                         fi_args->max_id = device->devid;
2356         }
2357         mutex_unlock(&fs_devices->device_list_mutex);
2358
2359         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2360                 ret = -EFAULT;
2361
2362         kfree(fi_args);
2363         return ret;
2364 }
2365
2366 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2367 {
2368         struct btrfs_ioctl_dev_info_args *di_args;
2369         struct btrfs_device *dev;
2370         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2371         int ret = 0;
2372         char *s_uuid = NULL;
2373         char empty_uuid[BTRFS_UUID_SIZE] = {0};
2374
2375         if (!capable(CAP_SYS_ADMIN))
2376                 return -EPERM;
2377
2378         di_args = memdup_user(arg, sizeof(*di_args));
2379         if (IS_ERR(di_args))
2380                 return PTR_ERR(di_args);
2381
2382         if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2383                 s_uuid = di_args->uuid;
2384
2385         mutex_lock(&fs_devices->device_list_mutex);
2386         dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2387         mutex_unlock(&fs_devices->device_list_mutex);
2388
2389         if (!dev) {
2390                 ret = -ENODEV;
2391                 goto out;
2392         }
2393
2394         di_args->devid = dev->devid;
2395         di_args->bytes_used = dev->bytes_used;
2396         di_args->total_bytes = dev->total_bytes;
2397         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2398         if (dev->name) {
2399                 struct rcu_string *name;
2400
2401                 rcu_read_lock();
2402                 name = rcu_dereference(dev->name);
2403                 strncpy(di_args->path, name->str, sizeof(di_args->path));
2404                 rcu_read_unlock();
2405                 di_args->path[sizeof(di_args->path) - 1] = 0;
2406         } else {
2407                 di_args->path[0] = '\0';
2408         }
2409
2410 out:
2411         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2412                 ret = -EFAULT;
2413
2414         kfree(di_args);
2415         return ret;
2416 }
2417
2418 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2419                                        u64 off, u64 olen, u64 destoff)
2420 {
2421         struct inode *inode = fdentry(file)->d_inode;
2422         struct btrfs_root *root = BTRFS_I(inode)->root;
2423         struct fd src_file;
2424         struct inode *src;
2425         struct btrfs_trans_handle *trans;
2426         struct btrfs_path *path;
2427         struct extent_buffer *leaf;
2428         char *buf;
2429         struct btrfs_key key;
2430         u32 nritems;
2431         int slot;
2432         int ret;
2433         u64 len = olen;
2434         u64 bs = root->fs_info->sb->s_blocksize;
2435
2436         /*
2437          * TODO:
2438          * - split compressed inline extents.  annoying: we need to
2439          *   decompress into destination's address_space (the file offset
2440          *   may change, so source mapping won't do), then recompress (or
2441          *   otherwise reinsert) a subrange.
2442          * - allow ranges within the same file to be cloned (provided
2443          *   they don't overlap)?
2444          */
2445
2446         /* the destination must be opened for writing */
2447         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2448                 return -EINVAL;
2449
2450         if (btrfs_root_readonly(root))
2451                 return -EROFS;
2452
2453         ret = mnt_want_write_file(file);
2454         if (ret)
2455                 return ret;
2456
2457         src_file = fdget(srcfd);
2458         if (!src_file.file) {
2459                 ret = -EBADF;
2460                 goto out_drop_write;
2461         }
2462
2463         ret = -EXDEV;
2464         if (src_file.file->f_path.mnt != file->f_path.mnt)
2465                 goto out_fput;
2466
2467         src = src_file.file->f_dentry->d_inode;
2468
2469         ret = -EINVAL;
2470         if (src == inode)
2471                 goto out_fput;
2472
2473         /* the src must be open for reading */
2474         if (!(src_file.file->f_mode & FMODE_READ))
2475                 goto out_fput;
2476
2477         /* don't make the dst file partly checksummed */
2478         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2479             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2480                 goto out_fput;
2481
2482         ret = -EISDIR;
2483         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2484                 goto out_fput;
2485
2486         ret = -EXDEV;
2487         if (src->i_sb != inode->i_sb)
2488                 goto out_fput;
2489
2490         ret = -ENOMEM;
2491         buf = vmalloc(btrfs_level_size(root, 0));
2492         if (!buf)
2493                 goto out_fput;
2494
2495         path = btrfs_alloc_path();
2496         if (!path) {
2497                 vfree(buf);
2498                 goto out_fput;
2499         }
2500         path->reada = 2;
2501
2502         if (inode < src) {
2503                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2504                 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2505         } else {
2506                 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2507                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2508         }
2509
2510         /* determine range to clone */
2511         ret = -EINVAL;
2512         if (off + len > src->i_size || off + len < off)
2513                 goto out_unlock;
2514         if (len == 0)
2515                 olen = len = src->i_size - off;
2516         /* if we extend to eof, continue to block boundary */
2517         if (off + len == src->i_size)
2518                 len = ALIGN(src->i_size, bs) - off;
2519
2520         /* verify the end result is block aligned */
2521         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2522             !IS_ALIGNED(destoff, bs))
2523                 goto out_unlock;
2524
2525         if (destoff > inode->i_size) {
2526                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2527                 if (ret)
2528                         goto out_unlock;
2529         }
2530
2531         /* truncate page cache pages from target inode range */
2532         truncate_inode_pages_range(&inode->i_data, destoff,
2533                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
2534
2535         /* do any pending delalloc/csum calc on src, one way or
2536            another, and lock file content */
2537         while (1) {
2538                 struct btrfs_ordered_extent *ordered;
2539                 lock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2540                 ordered = btrfs_lookup_first_ordered_extent(src, off + len - 1);
2541                 if (!ordered &&
2542                     !test_range_bit(&BTRFS_I(src)->io_tree, off, off + len - 1,
2543                                     EXTENT_DELALLOC, 0, NULL))
2544                         break;
2545                 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2546                 if (ordered)
2547                         btrfs_put_ordered_extent(ordered);
2548                 btrfs_wait_ordered_range(src, off, len);
2549         }
2550
2551         /* clone data */
2552         key.objectid = btrfs_ino(src);
2553         key.type = BTRFS_EXTENT_DATA_KEY;
2554         key.offset = 0;
2555
2556         while (1) {
2557                 /*
2558                  * note the key will change type as we walk through the
2559                  * tree.
2560                  */
2561                 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2562                                 0, 0);
2563                 if (ret < 0)
2564                         goto out;
2565
2566                 nritems = btrfs_header_nritems(path->nodes[0]);
2567                 if (path->slots[0] >= nritems) {
2568                         ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2569                         if (ret < 0)
2570                                 goto out;
2571                         if (ret > 0)
2572                                 break;
2573                         nritems = btrfs_header_nritems(path->nodes[0]);
2574                 }
2575                 leaf = path->nodes[0];
2576                 slot = path->slots[0];
2577
2578                 btrfs_item_key_to_cpu(leaf, &key, slot);
2579                 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2580                     key.objectid != btrfs_ino(src))
2581                         break;
2582
2583                 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2584                         struct btrfs_file_extent_item *extent;
2585                         int type;
2586                         u32 size;
2587                         struct btrfs_key new_key;
2588                         u64 disko = 0, diskl = 0;
2589                         u64 datao = 0, datal = 0;
2590                         u8 comp;
2591                         u64 endoff;
2592
2593                         size = btrfs_item_size_nr(leaf, slot);
2594                         read_extent_buffer(leaf, buf,
2595                                            btrfs_item_ptr_offset(leaf, slot),
2596                                            size);
2597
2598                         extent = btrfs_item_ptr(leaf, slot,
2599                                                 struct btrfs_file_extent_item);
2600                         comp = btrfs_file_extent_compression(leaf, extent);
2601                         type = btrfs_file_extent_type(leaf, extent);
2602                         if (type == BTRFS_FILE_EXTENT_REG ||
2603                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2604                                 disko = btrfs_file_extent_disk_bytenr(leaf,
2605                                                                       extent);
2606                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2607                                                                  extent);
2608                                 datao = btrfs_file_extent_offset(leaf, extent);
2609                                 datal = btrfs_file_extent_num_bytes(leaf,
2610                                                                     extent);
2611                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2612                                 /* take upper bound, may be compressed */
2613                                 datal = btrfs_file_extent_ram_bytes(leaf,
2614                                                                     extent);
2615                         }
2616                         btrfs_release_path(path);
2617
2618                         if (key.offset + datal <= off ||
2619                             key.offset >= off + len - 1)
2620                                 goto next;
2621
2622                         memcpy(&new_key, &key, sizeof(new_key));
2623                         new_key.objectid = btrfs_ino(inode);
2624                         if (off <= key.offset)
2625                                 new_key.offset = key.offset + destoff - off;
2626                         else
2627                                 new_key.offset = destoff;
2628
2629                         /*
2630                          * 1 - adjusting old extent (we may have to split it)
2631                          * 1 - add new extent
2632                          * 1 - inode update
2633                          */
2634                         trans = btrfs_start_transaction(root, 3);
2635                         if (IS_ERR(trans)) {
2636                                 ret = PTR_ERR(trans);
2637                                 goto out;
2638                         }
2639
2640                         if (type == BTRFS_FILE_EXTENT_REG ||
2641                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2642                                 /*
2643                                  *    a  | --- range to clone ---|  b
2644                                  * | ------------- extent ------------- |
2645                                  */
2646
2647                                 /* substract range b */
2648                                 if (key.offset + datal > off + len)
2649                                         datal = off + len - key.offset;
2650
2651                                 /* substract range a */
2652                                 if (off > key.offset) {
2653                                         datao += off - key.offset;
2654                                         datal -= off - key.offset;
2655                                 }
2656
2657                                 ret = btrfs_drop_extents(trans, root, inode,
2658                                                          new_key.offset,
2659                                                          new_key.offset + datal,
2660                                                          1);
2661                                 if (ret) {
2662                                         btrfs_abort_transaction(trans, root,
2663                                                                 ret);
2664                                         btrfs_end_transaction(trans, root);
2665                                         goto out;
2666                                 }
2667
2668                                 ret = btrfs_insert_empty_item(trans, root, path,
2669                                                               &new_key, size);
2670                                 if (ret) {
2671                                         btrfs_abort_transaction(trans, root,
2672                                                                 ret);
2673                                         btrfs_end_transaction(trans, root);
2674                                         goto out;
2675                                 }
2676
2677                                 leaf = path->nodes[0];
2678                                 slot = path->slots[0];
2679                                 write_extent_buffer(leaf, buf,
2680                                             btrfs_item_ptr_offset(leaf, slot),
2681                                             size);
2682
2683                                 extent = btrfs_item_ptr(leaf, slot,
2684                                                 struct btrfs_file_extent_item);
2685
2686                                 /* disko == 0 means it's a hole */
2687                                 if (!disko)
2688                                         datao = 0;
2689
2690                                 btrfs_set_file_extent_offset(leaf, extent,
2691                                                              datao);
2692                                 btrfs_set_file_extent_num_bytes(leaf, extent,
2693                                                                 datal);
2694                                 if (disko) {
2695                                         inode_add_bytes(inode, datal);
2696                                         ret = btrfs_inc_extent_ref(trans, root,
2697                                                         disko, diskl, 0,
2698                                                         root->root_key.objectid,
2699                                                         btrfs_ino(inode),
2700                                                         new_key.offset - datao,
2701                                                         0);
2702                                         if (ret) {
2703                                                 btrfs_abort_transaction(trans,
2704                                                                         root,
2705                                                                         ret);
2706                                                 btrfs_end_transaction(trans,
2707                                                                       root);
2708                                                 goto out;
2709
2710                                         }
2711                                 }
2712                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2713                                 u64 skip = 0;
2714                                 u64 trim = 0;
2715                                 if (off > key.offset) {
2716                                         skip = off - key.offset;
2717                                         new_key.offset += skip;
2718                                 }
2719
2720                                 if (key.offset + datal > off + len)
2721                                         trim = key.offset + datal - (off + len);
2722
2723                                 if (comp && (skip || trim)) {
2724                                         ret = -EINVAL;
2725                                         btrfs_end_transaction(trans, root);
2726                                         goto out;
2727                                 }
2728                                 size -= skip + trim;
2729                                 datal -= skip + trim;
2730
2731                                 ret = btrfs_drop_extents(trans, root, inode,
2732                                                          new_key.offset,
2733                                                          new_key.offset + datal,
2734                                                          1);
2735                                 if (ret) {
2736                                         btrfs_abort_transaction(trans, root,
2737                                                                 ret);
2738                                         btrfs_end_transaction(trans, root);
2739                                         goto out;
2740                                 }
2741
2742                                 ret = btrfs_insert_empty_item(trans, root, path,
2743                                                               &new_key, size);
2744                                 if (ret) {
2745                                         btrfs_abort_transaction(trans, root,
2746                                                                 ret);
2747                                         btrfs_end_transaction(trans, root);
2748                                         goto out;
2749                                 }
2750
2751                                 if (skip) {
2752                                         u32 start =
2753                                           btrfs_file_extent_calc_inline_size(0);
2754                                         memmove(buf+start, buf+start+skip,
2755                                                 datal);
2756                                 }
2757
2758                                 leaf = path->nodes[0];
2759                                 slot = path->slots[0];
2760                                 write_extent_buffer(leaf, buf,
2761                                             btrfs_item_ptr_offset(leaf, slot),
2762                                             size);
2763                                 inode_add_bytes(inode, datal);
2764                         }
2765
2766                         btrfs_mark_buffer_dirty(leaf);
2767                         btrfs_release_path(path);
2768
2769                         inode_inc_iversion(inode);
2770                         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2771
2772                         /*
2773                          * we round up to the block size at eof when
2774                          * determining which extents to clone above,
2775                          * but shouldn't round up the file size
2776                          */
2777                         endoff = new_key.offset + datal;
2778                         if (endoff > destoff+olen)
2779                                 endoff = destoff+olen;
2780                         if (endoff > inode->i_size)
2781                                 btrfs_i_size_write(inode, endoff);
2782
2783                         ret = btrfs_update_inode(trans, root, inode);
2784                         if (ret) {
2785                                 btrfs_abort_transaction(trans, root, ret);
2786                                 btrfs_end_transaction(trans, root);
2787                                 goto out;
2788                         }
2789                         ret = btrfs_end_transaction(trans, root);
2790                 }
2791 next:
2792                 btrfs_release_path(path);
2793                 key.offset++;
2794         }
2795         ret = 0;
2796 out:
2797         btrfs_release_path(path);
2798         unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2799 out_unlock:
2800         mutex_unlock(&src->i_mutex);
2801         mutex_unlock(&inode->i_mutex);
2802         vfree(buf);
2803         btrfs_free_path(path);
2804 out_fput:
2805         fdput(src_file);
2806 out_drop_write:
2807         mnt_drop_write_file(file);
2808         return ret;
2809 }
2810
2811 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2812 {
2813         struct btrfs_ioctl_clone_range_args args;
2814
2815         if (copy_from_user(&args, argp, sizeof(args)))
2816                 return -EFAULT;
2817         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2818                                  args.src_length, args.dest_offset);
2819 }
2820
2821 /*
2822  * there are many ways the trans_start and trans_end ioctls can lead
2823  * to deadlocks.  They should only be used by applications that
2824  * basically own the machine, and have a very in depth understanding
2825  * of all the possible deadlocks and enospc problems.
2826  */
2827 static long btrfs_ioctl_trans_start(struct file *file)
2828 {
2829         struct inode *inode = fdentry(file)->d_inode;
2830         struct btrfs_root *root = BTRFS_I(inode)->root;
2831         struct btrfs_trans_handle *trans;
2832         int ret;
2833
2834         ret = -EPERM;
2835         if (!capable(CAP_SYS_ADMIN))
2836                 goto out;
2837
2838         ret = -EINPROGRESS;
2839         if (file->private_data)
2840                 goto out;
2841
2842         ret = -EROFS;
2843         if (btrfs_root_readonly(root))
2844                 goto out;
2845
2846         ret = mnt_want_write_file(file);
2847         if (ret)
2848                 goto out;
2849
2850         atomic_inc(&root->fs_info->open_ioctl_trans);
2851
2852         ret = -ENOMEM;
2853         trans = btrfs_start_ioctl_transaction(root);
2854         if (IS_ERR(trans))
2855                 goto out_drop;
2856
2857         file->private_data = trans;
2858         return 0;
2859
2860 out_drop:
2861         atomic_dec(&root->fs_info->open_ioctl_trans);
2862         mnt_drop_write_file(file);
2863 out:
2864         return ret;
2865 }
2866
2867 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2868 {
2869         struct inode *inode = fdentry(file)->d_inode;
2870         struct btrfs_root *root = BTRFS_I(inode)->root;
2871         struct btrfs_root *new_root;
2872         struct btrfs_dir_item *di;
2873         struct btrfs_trans_handle *trans;
2874         struct btrfs_path *path;
2875         struct btrfs_key location;
2876         struct btrfs_disk_key disk_key;
2877         u64 objectid = 0;
2878         u64 dir_id;
2879         int ret;
2880
2881         if (!capable(CAP_SYS_ADMIN))
2882                 return -EPERM;
2883
2884         ret = mnt_want_write_file(file);
2885         if (ret)
2886                 return ret;
2887
2888         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
2889                 ret = -EFAULT;
2890                 goto out;
2891         }
2892
2893         if (!objectid)
2894                 objectid = root->root_key.objectid;
2895
2896         location.objectid = objectid;
2897         location.type = BTRFS_ROOT_ITEM_KEY;
2898         location.offset = (u64)-1;
2899
2900         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2901         if (IS_ERR(new_root)) {
2902                 ret = PTR_ERR(new_root);
2903                 goto out;
2904         }
2905
2906         if (btrfs_root_refs(&new_root->root_item) == 0) {
2907                 ret = -ENOENT;
2908                 goto out;
2909         }
2910
2911         path = btrfs_alloc_path();
2912         if (!path) {
2913                 ret = -ENOMEM;
2914                 goto out;
2915         }
2916         path->leave_spinning = 1;
2917
2918         trans = btrfs_start_transaction(root, 1);
2919         if (IS_ERR(trans)) {
2920                 btrfs_free_path(path);
2921                 ret = PTR_ERR(trans);
2922                 goto out;
2923         }
2924
2925         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2926         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2927                                    dir_id, "default", 7, 1);
2928         if (IS_ERR_OR_NULL(di)) {
2929                 btrfs_free_path(path);
2930                 btrfs_end_transaction(trans, root);
2931                 printk(KERN_ERR "Umm, you don't have the default dir item, "
2932                        "this isn't going to work\n");
2933                 ret = -ENOENT;
2934                 goto out;
2935         }
2936
2937         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2938         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2939         btrfs_mark_buffer_dirty(path->nodes[0]);
2940         btrfs_free_path(path);
2941
2942         btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
2943         btrfs_end_transaction(trans, root);
2944 out:
2945         mnt_drop_write_file(file);
2946         return ret;
2947 }
2948
2949 void btrfs_get_block_group_info(struct list_head *groups_list,
2950                                 struct btrfs_ioctl_space_info *space)
2951 {
2952         struct btrfs_block_group_cache *block_group;
2953
2954         space->total_bytes = 0;
2955         space->used_bytes = 0;
2956         space->flags = 0;
2957         list_for_each_entry(block_group, groups_list, list) {
2958                 space->flags = block_group->flags;
2959                 space->total_bytes += block_group->key.offset;
2960                 space->used_bytes +=
2961                         btrfs_block_group_used(&block_group->item);
2962         }
2963 }
2964
2965 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2966 {
2967         struct btrfs_ioctl_space_args space_args;
2968         struct btrfs_ioctl_space_info space;
2969         struct btrfs_ioctl_space_info *dest;
2970         struct btrfs_ioctl_space_info *dest_orig;
2971         struct btrfs_ioctl_space_info __user *user_dest;
2972         struct btrfs_space_info *info;
2973         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2974                        BTRFS_BLOCK_GROUP_SYSTEM,
2975                        BTRFS_BLOCK_GROUP_METADATA,
2976                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2977         int num_types = 4;
2978         int alloc_size;
2979         int ret = 0;
2980         u64 slot_count = 0;
2981         int i, c;
2982
2983         if (copy_from_user(&space_args,
2984                            (struct btrfs_ioctl_space_args __user *)arg,
2985                            sizeof(space_args)))
2986                 return -EFAULT;
2987
2988         for (i = 0; i < num_types; i++) {
2989                 struct btrfs_space_info *tmp;
2990
2991                 info = NULL;
2992                 rcu_read_lock();
2993                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2994                                         list) {
2995                         if (tmp->flags == types[i]) {
2996                                 info = tmp;
2997                                 break;
2998                         }
2999                 }
3000                 rcu_read_unlock();
3001
3002                 if (!info)
3003                         continue;
3004
3005                 down_read(&info->groups_sem);
3006                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3007                         if (!list_empty(&info->block_groups[c]))
3008                                 slot_count++;
3009                 }
3010                 up_read(&info->groups_sem);
3011         }
3012
3013         /* space_slots == 0 means they are asking for a count */
3014         if (space_args.space_slots == 0) {
3015                 space_args.total_spaces = slot_count;
3016                 goto out;
3017         }
3018
3019         slot_count = min_t(u64, space_args.space_slots, slot_count);
3020
3021         alloc_size = sizeof(*dest) * slot_count;
3022
3023         /* we generally have at most 6 or so space infos, one for each raid
3024          * level.  So, a whole page should be more than enough for everyone
3025          */
3026         if (alloc_size > PAGE_CACHE_SIZE)
3027                 return -ENOMEM;
3028
3029         space_args.total_spaces = 0;
3030         dest = kmalloc(alloc_size, GFP_NOFS);
3031         if (!dest)
3032                 return -ENOMEM;
3033         dest_orig = dest;
3034
3035         /* now we have a buffer to copy into */
3036         for (i = 0; i < num_types; i++) {
3037                 struct btrfs_space_info *tmp;
3038
3039                 if (!slot_count)
3040                         break;
3041
3042                 info = NULL;
3043                 rcu_read_lock();
3044                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3045                                         list) {
3046                         if (tmp->flags == types[i]) {
3047                                 info = tmp;
3048                                 break;
3049                         }
3050                 }
3051                 rcu_read_unlock();
3052
3053                 if (!info)
3054                         continue;
3055                 down_read(&info->groups_sem);
3056                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3057                         if (!list_empty(&info->block_groups[c])) {
3058                                 btrfs_get_block_group_info(
3059                                         &info->block_groups[c], &space);
3060                                 memcpy(dest, &space, sizeof(space));
3061                                 dest++;
3062                                 space_args.total_spaces++;
3063                                 slot_count--;
3064                         }
3065                         if (!slot_count)
3066                                 break;
3067                 }
3068                 up_read(&info->groups_sem);
3069         }
3070
3071         user_dest = (struct btrfs_ioctl_space_info __user *)
3072                 (arg + sizeof(struct btrfs_ioctl_space_args));
3073
3074         if (copy_to_user(user_dest, dest_orig, alloc_size))
3075                 ret = -EFAULT;
3076
3077         kfree(dest_orig);
3078 out:
3079         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3080                 ret = -EFAULT;
3081
3082         return ret;
3083 }
3084
3085 /*
3086  * there are many ways the trans_start and trans_end ioctls can lead
3087  * to deadlocks.  They should only be used by applications that
3088  * basically own the machine, and have a very in depth understanding
3089  * of all the possible deadlocks and enospc problems.
3090  */
3091 long btrfs_ioctl_trans_end(struct file *file)
3092 {
3093         struct inode *inode = fdentry(file)->d_inode;
3094         struct btrfs_root *root = BTRFS_I(inode)->root;
3095         struct btrfs_trans_handle *trans;
3096
3097         trans = file->private_data;
3098         if (!trans)
3099                 return -EINVAL;
3100         file->private_data = NULL;
3101
3102         btrfs_end_transaction(trans, root);
3103
3104         atomic_dec(&root->fs_info->open_ioctl_trans);
3105
3106         mnt_drop_write_file(file);
3107         return 0;
3108 }
3109
3110 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3111                                             void __user *argp)
3112 {
3113         struct btrfs_trans_handle *trans;
3114         u64 transid;
3115         int ret;
3116
3117         trans = btrfs_attach_transaction(root);
3118         if (IS_ERR(trans)) {
3119                 if (PTR_ERR(trans) != -ENOENT)
3120                         return PTR_ERR(trans);
3121
3122                 /* No running transaction, don't bother */
3123                 transid = root->fs_info->last_trans_committed;
3124                 goto out;
3125         }
3126         transid = trans->transid;
3127         ret = btrfs_commit_transaction_async(trans, root, 0);
3128         if (ret) {
3129                 btrfs_end_transaction(trans, root);
3130                 return ret;
3131         }
3132 out:
3133         if (argp)
3134                 if (copy_to_user(argp, &transid, sizeof(transid)))
3135                         return -EFAULT;
3136         return 0;
3137 }
3138
3139 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
3140                                            void __user *argp)
3141 {
3142         u64 transid;
3143
3144         if (argp) {
3145                 if (copy_from_user(&transid, argp, sizeof(transid)))
3146                         return -EFAULT;
3147         } else {
3148                 transid = 0;  /* current trans */
3149         }
3150         return btrfs_wait_for_commit(root, transid);
3151 }
3152
3153 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3154 {
3155         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3156         struct btrfs_ioctl_scrub_args *sa;
3157         int ret;
3158
3159         if (!capable(CAP_SYS_ADMIN))
3160                 return -EPERM;
3161
3162         sa = memdup_user(arg, sizeof(*sa));
3163         if (IS_ERR(sa))
3164                 return PTR_ERR(sa);
3165
3166         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3167                 ret = mnt_want_write_file(file);
3168                 if (ret)
3169                         goto out;
3170         }
3171
3172         ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3173                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3174                               0);
3175
3176         if (copy_to_user(arg, sa, sizeof(*sa)))
3177                 ret = -EFAULT;
3178
3179         if (!(sa->flags & BTRFS_SCRUB_READONLY))
3180                 mnt_drop_write_file(file);
3181 out:
3182         kfree(sa);
3183         return ret;
3184 }
3185
3186 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3187 {
3188         if (!capable(CAP_SYS_ADMIN))
3189                 return -EPERM;
3190
3191         return btrfs_scrub_cancel(root->fs_info);
3192 }
3193
3194 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3195                                        void __user *arg)
3196 {
3197         struct btrfs_ioctl_scrub_args *sa;
3198         int ret;
3199
3200         if (!capable(CAP_SYS_ADMIN))
3201                 return -EPERM;
3202
3203         sa = memdup_user(arg, sizeof(*sa));
3204         if (IS_ERR(sa))
3205                 return PTR_ERR(sa);
3206
3207         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3208
3209         if (copy_to_user(arg, sa, sizeof(*sa)))
3210                 ret = -EFAULT;
3211
3212         kfree(sa);
3213         return ret;
3214 }
3215
3216 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3217                                       void __user *arg)
3218 {
3219         struct btrfs_ioctl_get_dev_stats *sa;
3220         int ret;
3221
3222         sa = memdup_user(arg, sizeof(*sa));
3223         if (IS_ERR(sa))
3224                 return PTR_ERR(sa);
3225
3226         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3227                 kfree(sa);
3228                 return -EPERM;
3229         }
3230
3231         ret = btrfs_get_dev_stats(root, sa);
3232
3233         if (copy_to_user(arg, sa, sizeof(*sa)))
3234                 ret = -EFAULT;
3235
3236         kfree(sa);
3237         return ret;
3238 }
3239
3240 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3241 {
3242         struct btrfs_ioctl_dev_replace_args *p;
3243         int ret;
3244
3245         if (!capable(CAP_SYS_ADMIN))
3246                 return -EPERM;
3247
3248         p = memdup_user(arg, sizeof(*p));
3249         if (IS_ERR(p))
3250                 return PTR_ERR(p);
3251
3252         switch (p->cmd) {
3253         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3254                 if (atomic_xchg(
3255                         &root->fs_info->mutually_exclusive_operation_running,
3256                         1)) {
3257                         pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3258                         ret = -EINPROGRESS;
3259                 } else {
3260                         ret = btrfs_dev_replace_start(root, p);
3261                         atomic_set(
3262                          &root->fs_info->mutually_exclusive_operation_running,
3263                          0);
3264                 }
3265                 break;
3266         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3267                 btrfs_dev_replace_status(root->fs_info, p);
3268                 ret = 0;
3269                 break;
3270         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3271                 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3272                 break;
3273         default:
3274                 ret = -EINVAL;
3275                 break;
3276         }
3277
3278         if (copy_to_user(arg, p, sizeof(*p)))
3279                 ret = -EFAULT;
3280
3281         kfree(p);
3282         return ret;
3283 }
3284
3285 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3286 {
3287         int ret = 0;
3288         int i;
3289         u64 rel_ptr;
3290         int size;
3291         struct btrfs_ioctl_ino_path_args *ipa = NULL;
3292         struct inode_fs_paths *ipath = NULL;
3293         struct btrfs_path *path;
3294
3295         if (!capable(CAP_DAC_READ_SEARCH))
3296                 return -EPERM;
3297
3298         path = btrfs_alloc_path();
3299         if (!path) {
3300                 ret = -ENOMEM;
3301                 goto out;
3302         }
3303
3304         ipa = memdup_user(arg, sizeof(*ipa));
3305         if (IS_ERR(ipa)) {
3306                 ret = PTR_ERR(ipa);
3307                 ipa = NULL;
3308                 goto out;
3309         }
3310
3311         size = min_t(u32, ipa->size, 4096);
3312         ipath = init_ipath(size, root, path);
3313         if (IS_ERR(ipath)) {
3314                 ret = PTR_ERR(ipath);
3315                 ipath = NULL;
3316                 goto out;
3317         }
3318
3319         ret = paths_from_inode(ipa->inum, ipath);
3320         if (ret < 0)
3321                 goto out;
3322
3323         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3324                 rel_ptr = ipath->fspath->val[i] -
3325                           (u64)(unsigned long)ipath->fspath->val;
3326                 ipath->fspath->val[i] = rel_ptr;
3327         }
3328
3329         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3330                            (void *)(unsigned long)ipath->fspath, size);
3331         if (ret) {
3332                 ret = -EFAULT;
3333                 goto out;
3334         }
3335
3336 out:
3337         btrfs_free_path(path);
3338         free_ipath(ipath);
3339         kfree(ipa);
3340
3341         return ret;
3342 }
3343
3344 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3345 {
3346         struct btrfs_data_container *inodes = ctx;
3347         const size_t c = 3 * sizeof(u64);
3348
3349         if (inodes->bytes_left >= c) {
3350                 inodes->bytes_left -= c;
3351                 inodes->val[inodes->elem_cnt] = inum;
3352                 inodes->val[inodes->elem_cnt + 1] = offset;
3353                 inodes->val[inodes->elem_cnt + 2] = root;
3354                 inodes->elem_cnt += 3;
3355         } else {
3356                 inodes->bytes_missing += c - inodes->bytes_left;
3357                 inodes->bytes_left = 0;
3358                 inodes->elem_missed += 3;
3359         }
3360
3361         return 0;
3362 }
3363
3364 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3365                                         void __user *arg)
3366 {
3367         int ret = 0;
3368         int size;
3369         struct btrfs_ioctl_logical_ino_args *loi;
3370         struct btrfs_data_container *inodes = NULL;
3371         struct btrfs_path *path = NULL;
3372
3373         if (!capable(CAP_SYS_ADMIN))
3374                 return -EPERM;
3375
3376         loi = memdup_user(arg, sizeof(*loi));
3377         if (IS_ERR(loi)) {
3378                 ret = PTR_ERR(loi);
3379                 loi = NULL;
3380                 goto out;
3381         }
3382
3383         path = btrfs_alloc_path();
3384         if (!path) {
3385                 ret = -ENOMEM;
3386                 goto out;
3387         }
3388
3389         size = min_t(u32, loi->size, 64 * 1024);
3390         inodes = init_data_container(size);
3391         if (IS_ERR(inodes)) {
3392                 ret = PTR_ERR(inodes);
3393                 inodes = NULL;
3394                 goto out;
3395         }
3396
3397         ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3398                                           build_ino_list, inodes);
3399         if (ret == -EINVAL)
3400                 ret = -ENOENT;
3401         if (ret < 0)
3402                 goto out;
3403
3404         ret = copy_to_user((void *)(unsigned long)loi->inodes,
3405                            (void *)(unsigned long)inodes, size);
3406         if (ret)
3407                 ret = -EFAULT;
3408
3409 out:
3410         btrfs_free_path(path);
3411         vfree(inodes);
3412         kfree(loi);
3413
3414         return ret;
3415 }
3416
3417 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3418                                struct btrfs_ioctl_balance_args *bargs)
3419 {
3420         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3421
3422         bargs->flags = bctl->flags;
3423
3424         if (atomic_read(&fs_info->balance_running))
3425                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3426         if (atomic_read(&fs_info->balance_pause_req))
3427                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3428         if (atomic_read(&fs_info->balance_cancel_req))
3429                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3430
3431         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3432         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3433         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3434
3435         if (lock) {
3436                 spin_lock(&fs_info->balance_lock);
3437                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3438                 spin_unlock(&fs_info->balance_lock);
3439         } else {
3440                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3441         }
3442 }
3443
3444 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3445 {
3446         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3447         struct btrfs_fs_info *fs_info = root->fs_info;
3448         struct btrfs_ioctl_balance_args *bargs;
3449         struct btrfs_balance_control *bctl;
3450         bool need_unlock; /* for mut. excl. ops lock */
3451         int ret;
3452
3453         if (!capable(CAP_SYS_ADMIN))
3454                 return -EPERM;
3455
3456         ret = mnt_want_write_file(file);
3457         if (ret)
3458                 return ret;
3459
3460 again:
3461         if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
3462                 mutex_lock(&fs_info->volume_mutex);
3463                 mutex_lock(&fs_info->balance_mutex);
3464                 need_unlock = true;
3465                 goto locked;
3466         }
3467
3468         /*
3469          * mut. excl. ops lock is locked.  Three possibilites:
3470          *   (1) some other op is running
3471          *   (2) balance is running
3472          *   (3) balance is paused -- special case (think resume)
3473          */
3474         mutex_lock(&fs_info->balance_mutex);
3475         if (fs_info->balance_ctl) {
3476                 /* this is either (2) or (3) */
3477                 if (!atomic_read(&fs_info->balance_running)) {
3478                         mutex_unlock(&fs_info->balance_mutex);
3479                         if (!mutex_trylock(&fs_info->volume_mutex))
3480                                 goto again;
3481                         mutex_lock(&fs_info->balance_mutex);
3482
3483                         if (fs_info->balance_ctl &&
3484                             !atomic_read(&fs_info->balance_running)) {
3485                                 /* this is (3) */
3486                                 need_unlock = false;
3487                                 goto locked;
3488                         }
3489
3490                         mutex_unlock(&fs_info->balance_mutex);
3491                         mutex_unlock(&fs_info->volume_mutex);
3492                         goto again;
3493                 } else {
3494                         /* this is (2) */
3495                         mutex_unlock(&fs_info->balance_mutex);
3496                         ret = -EINPROGRESS;
3497                         goto out;
3498                 }
3499         } else {
3500                 /* this is (1) */
3501                 mutex_unlock(&fs_info->balance_mutex);
3502                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3503                 ret = -EINVAL;
3504                 goto out;
3505         }
3506
3507 locked:
3508         BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
3509
3510         if (arg) {
3511                 bargs = memdup_user(arg, sizeof(*bargs));
3512                 if (IS_ERR(bargs)) {
3513                         ret = PTR_ERR(bargs);
3514                         goto out_unlock;
3515                 }
3516
3517                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3518                         if (!fs_info->balance_ctl) {
3519                                 ret = -ENOTCONN;
3520                                 goto out_bargs;
3521                         }
3522
3523                         bctl = fs_info->balance_ctl;
3524                         spin_lock(&fs_info->balance_lock);
3525                         bctl->flags |= BTRFS_BALANCE_RESUME;
3526                         spin_unlock(&fs_info->balance_lock);
3527
3528                         goto do_balance;
3529                 }
3530         } else {
3531                 bargs = NULL;
3532         }
3533
3534         if (fs_info->balance_ctl) {
3535                 ret = -EINPROGRESS;
3536                 goto out_bargs;
3537         }
3538
3539         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3540         if (!bctl) {
3541                 ret = -ENOMEM;
3542                 goto out_bargs;
3543         }
3544
3545         bctl->fs_info = fs_info;
3546         if (arg) {
3547                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3548                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3549                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3550
3551                 bctl->flags = bargs->flags;
3552         } else {
3553                 /* balance everything - no filters */
3554                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3555         }
3556
3557 do_balance:
3558         /*
3559          * Ownership of bctl and mutually_exclusive_operation_running
3560          * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
3561          * or, if restriper was paused all the way until unmount, in
3562          * free_fs_info.  mutually_exclusive_operation_running is
3563          * cleared in __cancel_balance.
3564          */
3565         need_unlock = false;
3566
3567         ret = btrfs_balance(bctl, bargs);
3568
3569         if (arg) {
3570                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3571                         ret = -EFAULT;
3572         }
3573
3574 out_bargs:
3575         kfree(bargs);
3576 out_unlock:
3577         mutex_unlock(&fs_info->balance_mutex);
3578         mutex_unlock(&fs_info->volume_mutex);
3579         if (need_unlock)
3580                 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3581 out:
3582         mnt_drop_write_file(file);
3583         return ret;
3584 }
3585
3586 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3587 {
3588         if (!capable(CAP_SYS_ADMIN))
3589                 return -EPERM;
3590
3591         switch (cmd) {
3592         case BTRFS_BALANCE_CTL_PAUSE:
3593                 return btrfs_pause_balance(root->fs_info);
3594         case BTRFS_BALANCE_CTL_CANCEL:
3595                 return btrfs_cancel_balance(root->fs_info);
3596         }
3597
3598         return -EINVAL;
3599 }
3600
3601 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3602                                          void __user *arg)
3603 {
3604         struct btrfs_fs_info *fs_info = root->fs_info;
3605         struct btrfs_ioctl_balance_args *bargs;
3606         int ret = 0;
3607
3608         if (!capable(CAP_SYS_ADMIN))
3609                 return -EPERM;
3610
3611         mutex_lock(&fs_info->balance_mutex);
3612         if (!fs_info->balance_ctl) {
3613                 ret = -ENOTCONN;
3614                 goto out;
3615         }
3616
3617         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3618         if (!bargs) {
3619                 ret = -ENOMEM;
3620                 goto out;
3621         }
3622
3623         update_ioctl_balance_args(fs_info, 1, bargs);
3624
3625         if (copy_to_user(arg, bargs, sizeof(*bargs)))
3626                 ret = -EFAULT;
3627
3628         kfree(bargs);
3629 out:
3630         mutex_unlock(&fs_info->balance_mutex);
3631         return ret;
3632 }
3633
3634 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
3635 {
3636         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3637         struct btrfs_ioctl_quota_ctl_args *sa;
3638         struct btrfs_trans_handle *trans = NULL;
3639         int ret;
3640         int err;
3641
3642         if (!capable(CAP_SYS_ADMIN))
3643                 return -EPERM;
3644
3645         ret = mnt_want_write_file(file);
3646         if (ret)
3647                 return ret;
3648
3649         sa = memdup_user(arg, sizeof(*sa));
3650         if (IS_ERR(sa)) {
3651                 ret = PTR_ERR(sa);
3652                 goto drop_write;
3653         }
3654
3655         if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
3656                 trans = btrfs_start_transaction(root, 2);
3657                 if (IS_ERR(trans)) {
3658                         ret = PTR_ERR(trans);
3659                         goto out;
3660                 }
3661         }
3662
3663         switch (sa->cmd) {
3664         case BTRFS_QUOTA_CTL_ENABLE:
3665                 ret = btrfs_quota_enable(trans, root->fs_info);
3666                 break;
3667         case BTRFS_QUOTA_CTL_DISABLE:
3668                 ret = btrfs_quota_disable(trans, root->fs_info);
3669                 break;
3670         case BTRFS_QUOTA_CTL_RESCAN:
3671                 ret = btrfs_quota_rescan(root->fs_info);
3672                 break;
3673         default:
3674                 ret = -EINVAL;
3675                 break;
3676         }
3677
3678         if (copy_to_user(arg, sa, sizeof(*sa)))
3679                 ret = -EFAULT;
3680
3681         if (trans) {
3682                 err = btrfs_commit_transaction(trans, root);
3683                 if (err && !ret)
3684                         ret = err;
3685         }
3686 out:
3687         kfree(sa);
3688 drop_write:
3689         mnt_drop_write_file(file);
3690         return ret;
3691 }
3692
3693 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
3694 {
3695         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3696         struct btrfs_ioctl_qgroup_assign_args *sa;
3697         struct btrfs_trans_handle *trans;
3698         int ret;
3699         int err;
3700
3701         if (!capable(CAP_SYS_ADMIN))
3702                 return -EPERM;
3703
3704         ret = mnt_want_write_file(file);
3705         if (ret)
3706                 return ret;
3707
3708         sa = memdup_user(arg, sizeof(*sa));
3709         if (IS_ERR(sa)) {
3710                 ret = PTR_ERR(sa);
3711                 goto drop_write;
3712         }
3713
3714         trans = btrfs_join_transaction(root);
3715         if (IS_ERR(trans)) {
3716                 ret = PTR_ERR(trans);
3717                 goto out;
3718         }
3719
3720         /* FIXME: check if the IDs really exist */
3721         if (sa->assign) {
3722                 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
3723                                                 sa->src, sa->dst);
3724         } else {
3725                 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
3726                                                 sa->src, sa->dst);
3727         }
3728
3729         err = btrfs_end_transaction(trans, root);
3730         if (err && !ret)
3731                 ret = err;
3732
3733 out:
3734         kfree(sa);
3735 drop_write:
3736         mnt_drop_write_file(file);
3737         return ret;
3738 }
3739
3740 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
3741 {
3742         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3743         struct btrfs_ioctl_qgroup_create_args *sa;
3744         struct btrfs_trans_handle *trans;
3745         int ret;
3746         int err;
3747
3748         if (!capable(CAP_SYS_ADMIN))
3749                 return -EPERM;
3750
3751         ret = mnt_want_write_file(file);
3752         if (ret)
3753                 return ret;
3754
3755         sa = memdup_user(arg, sizeof(*sa));
3756         if (IS_ERR(sa)) {
3757                 ret = PTR_ERR(sa);
3758                 goto drop_write;
3759         }
3760
3761         if (!sa->qgroupid) {
3762                 ret = -EINVAL;
3763                 goto out;
3764         }
3765
3766         trans = btrfs_join_transaction(root);
3767         if (IS_ERR(trans)) {
3768                 ret = PTR_ERR(trans);
3769                 goto out;
3770         }
3771
3772         /* FIXME: check if the IDs really exist */
3773         if (sa->create) {
3774                 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
3775                                           NULL);
3776         } else {
3777                 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
3778         }
3779
3780         err = btrfs_end_transaction(trans, root);
3781         if (err && !ret)
3782                 ret = err;
3783
3784 out:
3785         kfree(sa);
3786 drop_write:
3787         mnt_drop_write_file(file);
3788         return ret;
3789 }
3790
3791 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
3792 {
3793         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3794         struct btrfs_ioctl_qgroup_limit_args *sa;
3795         struct btrfs_trans_handle *trans;
3796         int ret;
3797         int err;
3798         u64 qgroupid;
3799
3800         if (!capable(CAP_SYS_ADMIN))
3801                 return -EPERM;
3802
3803         ret = mnt_want_write_file(file);
3804         if (ret)
3805                 return ret;
3806
3807         sa = memdup_user(arg, sizeof(*sa));
3808         if (IS_ERR(sa)) {
3809                 ret = PTR_ERR(sa);
3810                 goto drop_write;
3811         }
3812
3813         trans = btrfs_join_transaction(root);
3814         if (IS_ERR(trans)) {
3815                 ret = PTR_ERR(trans);
3816                 goto out;
3817         }
3818
3819         qgroupid = sa->qgroupid;
3820         if (!qgroupid) {
3821                 /* take the current subvol as qgroup */
3822                 qgroupid = root->root_key.objectid;
3823         }
3824
3825         /* FIXME: check if the IDs really exist */
3826         ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
3827
3828         err = btrfs_end_transaction(trans, root);
3829         if (err && !ret)
3830                 ret = err;
3831
3832 out:
3833         kfree(sa);
3834 drop_write:
3835         mnt_drop_write_file(file);
3836         return ret;
3837 }
3838
3839 static long btrfs_ioctl_set_received_subvol(struct file *file,
3840                                             void __user *arg)
3841 {
3842         struct btrfs_ioctl_received_subvol_args *sa = NULL;
3843         struct inode *inode = fdentry(file)->d_inode;
3844         struct btrfs_root *root = BTRFS_I(inode)->root;
3845         struct btrfs_root_item *root_item = &root->root_item;
3846         struct btrfs_trans_handle *trans;
3847         struct timespec ct = CURRENT_TIME;
3848         int ret = 0;
3849
3850         ret = mnt_want_write_file(file);
3851         if (ret < 0)
3852                 return ret;
3853
3854         down_write(&root->fs_info->subvol_sem);
3855
3856         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
3857                 ret = -EINVAL;
3858                 goto out;
3859         }
3860
3861         if (btrfs_root_readonly(root)) {
3862                 ret = -EROFS;
3863                 goto out;
3864         }
3865
3866         if (!inode_owner_or_capable(inode)) {
3867                 ret = -EACCES;
3868                 goto out;
3869         }
3870
3871         sa = memdup_user(arg, sizeof(*sa));
3872         if (IS_ERR(sa)) {
3873                 ret = PTR_ERR(sa);
3874                 sa = NULL;
3875                 goto out;
3876         }
3877
3878         trans = btrfs_start_transaction(root, 1);
3879         if (IS_ERR(trans)) {
3880                 ret = PTR_ERR(trans);
3881                 trans = NULL;
3882                 goto out;
3883         }
3884
3885         sa->rtransid = trans->transid;
3886         sa->rtime.sec = ct.tv_sec;
3887         sa->rtime.nsec = ct.tv_nsec;
3888
3889         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
3890         btrfs_set_root_stransid(root_item, sa->stransid);
3891         btrfs_set_root_rtransid(root_item, sa->rtransid);
3892         root_item->stime.sec = cpu_to_le64(sa->stime.sec);
3893         root_item->stime.nsec = cpu_to_le32(sa->stime.nsec);
3894         root_item->rtime.sec = cpu_to_le64(sa->rtime.sec);
3895         root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec);
3896
3897         ret = btrfs_update_root(trans, root->fs_info->tree_root,
3898                                 &root->root_key, &root->root_item);
3899         if (ret < 0) {
3900                 btrfs_end_transaction(trans, root);
3901                 trans = NULL;
3902                 goto out;
3903         } else {
3904                 ret = btrfs_commit_transaction(trans, root);
3905                 if (ret < 0)
3906                         goto out;
3907         }
3908
3909         ret = copy_to_user(arg, sa, sizeof(*sa));
3910         if (ret)
3911                 ret = -EFAULT;
3912
3913 out:
3914         kfree(sa);
3915         up_write(&root->fs_info->subvol_sem);
3916         mnt_drop_write_file(file);
3917         return ret;
3918 }
3919
3920 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
3921 {
3922         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3923         const char *label = root->fs_info->super_copy->label;
3924         size_t len = strnlen(label, BTRFS_LABEL_SIZE);
3925         int ret;
3926
3927         if (len == BTRFS_LABEL_SIZE) {
3928                 pr_warn("btrfs: label is too long, return the first %zu bytes\n",
3929                         --len);
3930         }
3931
3932         mutex_lock(&root->fs_info->volume_mutex);
3933         ret = copy_to_user(arg, label, len);
3934         mutex_unlock(&root->fs_info->volume_mutex);
3935
3936         return ret ? -EFAULT : 0;
3937 }
3938
3939 long btrfs_ioctl(struct file *file, unsigned int
3940                 cmd, unsigned long arg)
3941 {
3942         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3943         void __user *argp = (void __user *)arg;
3944
3945         switch (cmd) {
3946         case FS_IOC_GETFLAGS:
3947                 return btrfs_ioctl_getflags(file, argp);
3948         case FS_IOC_SETFLAGS:
3949                 return btrfs_ioctl_setflags(file, argp);
3950         case FS_IOC_GETVERSION:
3951                 return btrfs_ioctl_getversion(file, argp);
3952         case FITRIM:
3953                 return btrfs_ioctl_fitrim(file, argp);
3954         case BTRFS_IOC_SNAP_CREATE:
3955                 return btrfs_ioctl_snap_create(file, argp, 0);
3956         case BTRFS_IOC_SNAP_CREATE_V2:
3957                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
3958         case BTRFS_IOC_SUBVOL_CREATE:
3959                 return btrfs_ioctl_snap_create(file, argp, 1);
3960         case BTRFS_IOC_SUBVOL_CREATE_V2:
3961                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
3962         case BTRFS_IOC_SNAP_DESTROY:
3963                 return btrfs_ioctl_snap_destroy(file, argp);
3964         case BTRFS_IOC_SUBVOL_GETFLAGS:
3965                 return btrfs_ioctl_subvol_getflags(file, argp);
3966         case BTRFS_IOC_SUBVOL_SETFLAGS:
3967                 return btrfs_ioctl_subvol_setflags(file, argp);
3968         case BTRFS_IOC_DEFAULT_SUBVOL:
3969                 return btrfs_ioctl_default_subvol(file, argp);
3970         case BTRFS_IOC_DEFRAG:
3971                 return btrfs_ioctl_defrag(file, NULL);
3972         case BTRFS_IOC_DEFRAG_RANGE:
3973                 return btrfs_ioctl_defrag(file, argp);
3974         case BTRFS_IOC_RESIZE:
3975                 return btrfs_ioctl_resize(file, argp);
3976         case BTRFS_IOC_ADD_DEV:
3977                 return btrfs_ioctl_add_dev(root, argp);
3978         case BTRFS_IOC_RM_DEV:
3979                 return btrfs_ioctl_rm_dev(file, argp);
3980         case BTRFS_IOC_FS_INFO:
3981                 return btrfs_ioctl_fs_info(root, argp);
3982         case BTRFS_IOC_DEV_INFO:
3983                 return btrfs_ioctl_dev_info(root, argp);
3984         case BTRFS_IOC_BALANCE:
3985                 return btrfs_ioctl_balance(file, NULL);
3986         case BTRFS_IOC_CLONE:
3987                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
3988         case BTRFS_IOC_CLONE_RANGE:
3989                 return btrfs_ioctl_clone_range(file, argp);
3990         case BTRFS_IOC_TRANS_START:
3991                 return btrfs_ioctl_trans_start(file);
3992         case BTRFS_IOC_TRANS_END:
3993                 return btrfs_ioctl_trans_end(file);
3994         case BTRFS_IOC_TREE_SEARCH:
3995                 return btrfs_ioctl_tree_search(file, argp);
3996         case BTRFS_IOC_INO_LOOKUP:
3997                 return btrfs_ioctl_ino_lookup(file, argp);
3998         case BTRFS_IOC_INO_PATHS:
3999                 return btrfs_ioctl_ino_to_path(root, argp);
4000         case BTRFS_IOC_LOGICAL_INO:
4001                 return btrfs_ioctl_logical_to_ino(root, argp);
4002         case BTRFS_IOC_SPACE_INFO:
4003                 return btrfs_ioctl_space_info(root, argp);
4004         case BTRFS_IOC_SYNC:
4005                 btrfs_sync_fs(file->f_dentry->d_sb, 1);
4006                 return 0;
4007         case BTRFS_IOC_START_SYNC:
4008                 return btrfs_ioctl_start_sync(root, argp);
4009         case BTRFS_IOC_WAIT_SYNC:
4010                 return btrfs_ioctl_wait_sync(root, argp);
4011         case BTRFS_IOC_SCRUB:
4012                 return btrfs_ioctl_scrub(file, argp);
4013         case BTRFS_IOC_SCRUB_CANCEL:
4014                 return btrfs_ioctl_scrub_cancel(root, argp);
4015         case BTRFS_IOC_SCRUB_PROGRESS:
4016                 return btrfs_ioctl_scrub_progress(root, argp);
4017         case BTRFS_IOC_BALANCE_V2:
4018                 return btrfs_ioctl_balance(file, argp);
4019         case BTRFS_IOC_BALANCE_CTL:
4020                 return btrfs_ioctl_balance_ctl(root, arg);
4021         case BTRFS_IOC_BALANCE_PROGRESS:
4022                 return btrfs_ioctl_balance_progress(root, argp);
4023         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4024                 return btrfs_ioctl_set_received_subvol(file, argp);
4025         case BTRFS_IOC_SEND:
4026                 return btrfs_ioctl_send(file, argp);
4027         case BTRFS_IOC_GET_DEV_STATS:
4028                 return btrfs_ioctl_get_dev_stats(root, argp);
4029         case BTRFS_IOC_QUOTA_CTL:
4030                 return btrfs_ioctl_quota_ctl(file, argp);
4031         case BTRFS_IOC_QGROUP_ASSIGN:
4032                 return btrfs_ioctl_qgroup_assign(file, argp);
4033         case BTRFS_IOC_QGROUP_CREATE:
4034                 return btrfs_ioctl_qgroup_create(file, argp);
4035         case BTRFS_IOC_QGROUP_LIMIT:
4036                 return btrfs_ioctl_qgroup_limit(file, argp);
4037         case BTRFS_IOC_DEV_REPLACE:
4038                 return btrfs_ioctl_dev_replace(root, argp);
4039         case BTRFS_IOC_GET_FSLABEL:
4040                 return btrfs_ioctl_get_fslabel(file, argp);
4041         }
4042
4043         return -ENOTTY;
4044 }