fs/btrfs/ioctl.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/bio.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/file.h>
  23 #include <linux/fs.h>
  24 #include <linux/fsnotify.h>
  25 #include <linux/pagemap.h>
  26 #include <linux/highmem.h>
  27 #include <linux/time.h>
  28 #include <linux/init.h>
  29 #include <linux/string.h>
  30 #include <linux/backing-dev.h>
  31 #include <linux/mount.h>
  32 #include <linux/mpage.h>
  33 #include <linux/namei.h>
  34 #include <linux/swap.h>
  35 #include <linux/writeback.h>
  36 #include <linux/statfs.h>
  37 #include <linux/compat.h>
  38 #include <linux/bit_spinlock.h>
  39 #include <linux/security.h>
  40 #include <linux/xattr.h>
  41 #include <linux/vmalloc.h>
  42 #include <linux/slab.h>
  43 #include <linux/blkdev.h>
  44 #include "compat.h"
  45 #include "ctree.h"
  46 #include "disk-io.h"
  47 #include "transaction.h"
  48 #include "btrfs_inode.h"
  49 #include "ioctl.h"
  50 #include "print-tree.h"
  51 #include "volumes.h"
  52 #include "locking.h"
  53 #include "inode-map.h"
  54 #include "backref.h"
  55
  56 /* Mask out flags that are inappropriate for the given type of inode. */
  57 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
  58 {
  59         if (S_ISDIR(mode))
  60                 return flags;
  61         else if (S_ISREG(mode))
  62                 return flags & ~FS_DIRSYNC_FL;
  63         else
  64                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
  65 }
  66
  67 /*
  68  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
  69  */
  70 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
  71 {
  72         unsigned int iflags = 0;
  73
  74         if (flags & BTRFS_INODE_SYNC)
  75                 iflags |= FS_SYNC_FL;
  76         if (flags & BTRFS_INODE_IMMUTABLE)
  77                 iflags |= FS_IMMUTABLE_FL;
  78         if (flags & BTRFS_INODE_APPEND)
  79                 iflags |= FS_APPEND_FL;
  80         if (flags & BTRFS_INODE_NODUMP)
  81                 iflags |= FS_NODUMP_FL;
  82         if (flags & BTRFS_INODE_NOATIME)
  83                 iflags |= FS_NOATIME_FL;
  84         if (flags & BTRFS_INODE_DIRSYNC)
  85                 iflags |= FS_DIRSYNC_FL;
  86         if (flags & BTRFS_INODE_NODATACOW)
  87                 iflags |= FS_NOCOW_FL;
  88
  89         if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
  90                 iflags |= FS_COMPR_FL;
  91         else if (flags & BTRFS_INODE_NOCOMPRESS)
  92                 iflags |= FS_NOCOMP_FL;
  93
  94         return iflags;
  95 }
  96
  97 /*
  98  * Update inode->i_flags based on the btrfs internal flags.
  99  */
 100 void btrfs_update_iflags(struct inode *inode)
 101 {
 102         struct btrfs_inode *ip = BTRFS_I(inode);
 103
 104         inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
 105
 106         if (ip->flags & BTRFS_INODE_SYNC)
 107                 inode->i_flags |= S_SYNC;
 108         if (ip->flags & BTRFS_INODE_IMMUTABLE)
 109                 inode->i_flags |= S_IMMUTABLE;
 110         if (ip->flags & BTRFS_INODE_APPEND)
 111                 inode->i_flags |= S_APPEND;
 112         if (ip->flags & BTRFS_INODE_NOATIME)
 113                 inode->i_flags |= S_NOATIME;
 114         if (ip->flags & BTRFS_INODE_DIRSYNC)
 115                 inode->i_flags |= S_DIRSYNC;
 116 }
 117
 118 /*
 119  * Inherit flags from the parent inode.
 120  *
 121  * Currently only the compression flags and the cow flags are inherited.
 122  */
 123 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 124 {
 125         unsigned int flags;
 126
 127         if (!dir)
 128                 return;
 129
 130         flags = BTRFS_I(dir)->flags;
 131
 132         if (flags & BTRFS_INODE_NOCOMPRESS) {
 133                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 134                 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 135         } else if (flags & BTRFS_INODE_COMPRESS) {
 136                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 137                 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 138         }
 139
 140         if (flags & BTRFS_INODE_NODATACOW)
 141                 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 142
 143         btrfs_update_iflags(inode);
 144 }
 145
 146 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 147 {
 148         struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
 149         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 150
 151         if (copy_to_user(arg, &flags, sizeof(flags)))
 152                 return -EFAULT;
 153         return 0;
 154 }
 155
 156 static int check_flags(unsigned int flags)
 157 {
 158         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 159                       FS_NOATIME_FL | FS_NODUMP_FL | \
 160                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 161                       FS_NOCOMP_FL | FS_COMPR_FL |
 162                       FS_NOCOW_FL))
 163                 return -EOPNOTSUPP;
 164
 165         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 166                 return -EINVAL;
 167
 168         return 0;
 169 }
 170
 171 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 172 {
 173         struct inode *inode = file->f_path.dentry->d_inode;
 174         struct btrfs_inode *ip = BTRFS_I(inode);
 175         struct btrfs_root *root = ip->root;
 176         struct btrfs_trans_handle *trans;
 177         unsigned int flags, oldflags;
 178         int ret;
 179         u64 ip_oldflags;
 180         unsigned int i_oldflags;
 181
 182         if (btrfs_root_readonly(root))
 183                 return -EROFS;
 184
 185         if (copy_from_user(&flags, arg, sizeof(flags)))
 186                 return -EFAULT;
 187
 188         ret = check_flags(flags);
 189         if (ret)
 190                 return ret;
 191
 192         if (!inode_owner_or_capable(inode))
 193                 return -EACCES;
 194
 195         mutex_lock(&inode->i_mutex);
 196
 197         ip_oldflags = ip->flags;
 198         i_oldflags = inode->i_flags;
 199
 200         flags = btrfs_mask_flags(inode->i_mode, flags);
 201         oldflags = btrfs_flags_to_ioctl(ip->flags);
 202         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 203                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 204                         ret = -EPERM;
 205                         goto out_unlock;
 206                 }
 207         }
 208
 209         ret = mnt_want_write_file(file);
 210         if (ret)
 211                 goto out_unlock;
 212
 213         if (flags & FS_SYNC_FL)
 214                 ip->flags |= BTRFS_INODE_SYNC;
 215         else
 216                 ip->flags &= ~BTRFS_INODE_SYNC;
 217         if (flags & FS_IMMUTABLE_FL)
 218                 ip->flags |= BTRFS_INODE_IMMUTABLE;
 219         else
 220                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 221         if (flags & FS_APPEND_FL)
 222                 ip->flags |= BTRFS_INODE_APPEND;
 223         else
 224                 ip->flags &= ~BTRFS_INODE_APPEND;
 225         if (flags & FS_NODUMP_FL)
 226                 ip->flags |= BTRFS_INODE_NODUMP;
 227         else
 228                 ip->flags &= ~BTRFS_INODE_NODUMP;
 229         if (flags & FS_NOATIME_FL)
 230                 ip->flags |= BTRFS_INODE_NOATIME;
 231         else
 232                 ip->flags &= ~BTRFS_INODE_NOATIME;
 233         if (flags & FS_DIRSYNC_FL)
 234                 ip->flags |= BTRFS_INODE_DIRSYNC;
 235         else
 236                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
 237         if (flags & FS_NOCOW_FL)
 238                 ip->flags |= BTRFS_INODE_NODATACOW;
 239         else
 240                 ip->flags &= ~BTRFS_INODE_NODATACOW;
 241
 242         /*
 243          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 244          * flag may be changed automatically if compression code won't make
 245          * things smaller.
 246          */
 247         if (flags & FS_NOCOMP_FL) {
 248                 ip->flags &= ~BTRFS_INODE_COMPRESS;
 249                 ip->flags |= BTRFS_INODE_NOCOMPRESS;
 250         } else if (flags & FS_COMPR_FL) {
 251                 ip->flags |= BTRFS_INODE_COMPRESS;
 252                 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 253         } else {
 254                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 255         }
 256
 257         trans = btrfs_start_transaction(root, 1);
 258         if (IS_ERR(trans)) {
 259                 ret = PTR_ERR(trans);
 260                 goto out_drop;
 261         }
 262
 263         btrfs_update_iflags(inode);
 264         inode->i_ctime = CURRENT_TIME;
 265         ret = btrfs_update_inode(trans, root, inode);
 266
 267         btrfs_end_transaction(trans, root);
 268  out_drop:
 269         if (ret) {
 270                 ip->flags = ip_oldflags;
 271                 inode->i_flags = i_oldflags;
 272         }
 273
 274         mnt_drop_write_file(file);
 275  out_unlock:
 276         mutex_unlock(&inode->i_mutex);
 277         return ret;
 278 }
 279
 280 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 281 {
 282         struct inode *inode = file->f_path.dentry->d_inode;
 283
 284         return put_user(inode->i_generation, arg);
 285 }
 286
 287 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 288 {
 289         struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
 290         struct btrfs_device *device;
 291         struct request_queue *q;
 292         struct fstrim_range range;
 293         u64 minlen = ULLONG_MAX;
 294         u64 num_devices = 0;
 295         u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 296         int ret;
 297
 298         if (!capable(CAP_SYS_ADMIN))
 299                 return -EPERM;
 300
 301         rcu_read_lock();
 302         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 303                                 dev_list) {
 304                 if (!device->bdev)
 305                         continue;
 306                 q = bdev_get_queue(device->bdev);
 307                 if (blk_queue_discard(q)) {
 308                         num_devices++;
 309                         minlen = min((u64)q->limits.discard_granularity,
 310                                      minlen);
 311                 }
 312         }
 313         rcu_read_unlock();
 314
 315         if (!num_devices)
 316                 return -EOPNOTSUPP;
 317         if (copy_from_user(&range, arg, sizeof(range)))
 318                 return -EFAULT;
 319         if (range.start > total_bytes)
 320                 return -EINVAL;
 321
 322         range.len = min(range.len, total_bytes - range.start);
 323         range.minlen = max(range.minlen, minlen);
 324         ret = btrfs_trim_fs(fs_info->tree_root, &range);
 325         if (ret < 0)
 326                 return ret;
 327
 328         if (copy_to_user(arg, &range, sizeof(range)))
 329                 return -EFAULT;
 330
 331         return 0;
 332 }
 333
 334 static noinline int create_subvol(struct btrfs_root *root,
 335                                   struct dentry *dentry,
 336                                   char *name, int namelen,
 337                                   u64 *async_transid)
 338 {
 339         struct btrfs_trans_handle *trans;
 340         struct btrfs_key key;
 341         struct btrfs_root_item root_item;
 342         struct btrfs_inode_item *inode_item;
 343         struct extent_buffer *leaf;
 344         struct btrfs_root *new_root;
 345         struct dentry *parent = dentry->d_parent;
 346         struct inode *dir;
 347         int ret;
 348         int err;
 349         u64 objectid;
 350         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 351         u64 index = 0;
 352
 353         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 354         if (ret)
 355                 return ret;
 356
 357         dir = parent->d_inode;
 358
 359         /*
 360          * 1 - inode item
 361          * 2 - refs
 362          * 1 - root item
 363          * 2 - dir items
 364          */
 365         trans = btrfs_start_transaction(root, 6);
 366         if (IS_ERR(trans))
 367                 return PTR_ERR(trans);
 368
 369         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
 370                                       0, objectid, NULL, 0, 0, 0, 0);
 371         if (IS_ERR(leaf)) {
 372                 ret = PTR_ERR(leaf);
 373                 goto fail;
 374         }
 375
 376         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 377         btrfs_set_header_bytenr(leaf, leaf->start);
 378         btrfs_set_header_generation(leaf, trans->transid);
 379         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 380         btrfs_set_header_owner(leaf, objectid);
 381
 382         write_extent_buffer(leaf, root->fs_info->fsid,
 383                             (unsigned long)btrfs_header_fsid(leaf),
 384                             BTRFS_FSID_SIZE);
 385         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 386                             (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
 387                             BTRFS_UUID_SIZE);
 388         btrfs_mark_buffer_dirty(leaf);
 389
 390         inode_item = &root_item.inode;
 391         memset(inode_item, 0, sizeof(*inode_item));
 392         inode_item->generation = cpu_to_le64(1);
 393         inode_item->size = cpu_to_le64(3);
 394         inode_item->nlink = cpu_to_le32(1);
 395         inode_item->nbytes = cpu_to_le64(root->leafsize);
 396         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 397
 398         root_item.flags = 0;
 399         root_item.byte_limit = 0;
 400         inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
 401
 402         btrfs_set_root_bytenr(&root_item, leaf->start);
 403         btrfs_set_root_generation(&root_item, trans->transid);
 404         btrfs_set_root_level(&root_item, 0);
 405         btrfs_set_root_refs(&root_item, 1);
 406         btrfs_set_root_used(&root_item, leaf->len);
 407         btrfs_set_root_last_snapshot(&root_item, 0);
 408
 409         memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
 410         root_item.drop_level = 0;
 411
 412         btrfs_tree_unlock(leaf);
 413         free_extent_buffer(leaf);
 414         leaf = NULL;
 415
 416         btrfs_set_root_dirid(&root_item, new_dirid);
 417
 418         key.objectid = objectid;
 419         key.offset = 0;
 420         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 421         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 422                                 &root_item);
 423         if (ret)
 424                 goto fail;
 425
 426         key.offset = (u64)-1;
 427         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 428         if (IS_ERR(new_root)) {
 429                 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 430                 ret = PTR_ERR(new_root);
 431                 goto fail;
 432         }
 433
 434         btrfs_record_root_in_trans(trans, new_root);
 435
 436         ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
 437         if (ret) {
 438                 /* We potentially lose an unused inode item here */
 439                 btrfs_abort_transaction(trans, root, ret);
 440                 goto fail;
 441         }
 442
 443         /*
 444          * insert the directory item
 445          */
 446         ret = btrfs_set_inode_index(dir, &index);
 447         if (ret) {
 448                 btrfs_abort_transaction(trans, root, ret);
 449                 goto fail;
 450         }
 451
 452         ret = btrfs_insert_dir_item(trans, root,
 453                                     name, namelen, dir, &key,
 454                                     BTRFS_FT_DIR, index);
 455         if (ret) {
 456                 btrfs_abort_transaction(trans, root, ret);
 457                 goto fail;
 458         }
 459
 460         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 461         ret = btrfs_update_inode(trans, root, dir);
 462         BUG_ON(ret);
 463
 464         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 465                                  objectid, root->root_key.objectid,
 466                                  btrfs_ino(dir), index, name, namelen);
 467
 468         BUG_ON(ret);
 469
 470         d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 471 fail:
 472         if (async_transid) {
 473                 *async_transid = trans->transid;
 474                 err = btrfs_commit_transaction_async(trans, root, 1);
 475         } else {
 476                 err = btrfs_commit_transaction(trans, root);
 477         }
 478         if (err && !ret)
 479                 ret = err;
 480         return ret;
 481 }
 482
 483 static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
 484                            char *name, int namelen, u64 *async_transid,
 485                            bool readonly)
 486 {
 487         struct inode *inode;
 488         struct btrfs_pending_snapshot *pending_snapshot;
 489         struct btrfs_trans_handle *trans;
 490         int ret;
 491
 492         if (!root->ref_cows)
 493                 return -EINVAL;
 494
 495         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 496         if (!pending_snapshot)
 497                 return -ENOMEM;
 498
 499         btrfs_init_block_rsv(&pending_snapshot->block_rsv);
 500         pending_snapshot->dentry = dentry;
 501         pending_snapshot->root = root;
 502         pending_snapshot->readonly = readonly;
 503
 504         trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
 505         if (IS_ERR(trans)) {
 506                 ret = PTR_ERR(trans);
 507                 goto fail;
 508         }
 509
 510         ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
 511         BUG_ON(ret);
 512
 513         spin_lock(&root->fs_info->trans_lock);
 514         list_add(&pending_snapshot->list,
 515                  &trans->transaction->pending_snapshots);
 516         spin_unlock(&root->fs_info->trans_lock);
 517         if (async_transid) {
 518                 *async_transid = trans->transid;
 519                 ret = btrfs_commit_transaction_async(trans,
 520                                      root->fs_info->extent_root, 1);
 521         } else {
 522                 ret = btrfs_commit_transaction(trans,
 523                                                root->fs_info->extent_root);
 524         }
 525         BUG_ON(ret);
 526
 527         ret = pending_snapshot->error;
 528         if (ret)
 529                 goto fail;
 530
 531         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 532         if (ret)
 533                 goto fail;
 534
 535         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 536         if (IS_ERR(inode)) {
 537                 ret = PTR_ERR(inode);
 538                 goto fail;
 539         }
 540         BUG_ON(!inode);
 541         d_instantiate(dentry, inode);
 542         ret = 0;
 543 fail:
 544         kfree(pending_snapshot);
 545         return ret;
 546 }
 547
 548 /*  copy of check_sticky in fs/namei.c()
 549 * It's inline, so penalty for filesystems that don't use sticky bit is
 550 * minimal.
 551 */
 552 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 553 {
 554         uid_t fsuid = current_fsuid();
 555
 556         if (!(dir->i_mode & S_ISVTX))
 557                 return 0;
 558         if (inode->i_uid == fsuid)
 559                 return 0;
 560         if (dir->i_uid == fsuid)
 561                 return 0;
 562         return !capable(CAP_FOWNER);
 563 }
 564
 565 /*  copy of may_delete in fs/namei.c()
 566  *      Check whether we can remove a link victim from directory dir, check
 567  *  whether the type of victim is right.
 568  *  1. We can't do it if dir is read-only (done in permission())
 569  *  2. We should have write and exec permissions on dir
 570  *  3. We can't remove anything from append-only dir
 571  *  4. We can't do anything with immutable dir (done in permission())
 572  *  5. If the sticky bit on dir is set we should either
 573  *      a. be owner of dir, or
 574  *      b. be owner of victim, or
 575  *      c. have CAP_FOWNER capability
 576  *  6. If the victim is append-only or immutable we can't do antyhing with
 577  *     links pointing to it.
 578  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 579  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 580  *  9. We can't remove a root or mountpoint.
 581  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 582  *     nfs_async_unlink().
 583  */
 584
 585 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
 586 {
 587         int error;
 588
 589         if (!victim->d_inode)
 590                 return -ENOENT;
 591
 592         BUG_ON(victim->d_parent->d_inode != dir);
 593         audit_inode_child(victim, dir);
 594
 595         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 596         if (error)
 597                 return error;
 598         if (IS_APPEND(dir))
 599                 return -EPERM;
 600         if (btrfs_check_sticky(dir, victim->d_inode)||
 601                 IS_APPEND(victim->d_inode)||
 602             IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 603                 return -EPERM;
 604         if (isdir) {
 605                 if (!S_ISDIR(victim->d_inode->i_mode))
 606                         return -ENOTDIR;
 607                 if (IS_ROOT(victim))
 608                         return -EBUSY;
 609         } else if (S_ISDIR(victim->d_inode->i_mode))
 610                 return -EISDIR;
 611         if (IS_DEADDIR(dir))
 612                 return -ENOENT;
 613         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 614                 return -EBUSY;
 615         return 0;
 616 }
 617
 618 /* copy of may_create in fs/namei.c() */
 619 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 620 {
 621         if (child->d_inode)
 622                 return -EEXIST;
 623         if (IS_DEADDIR(dir))
 624                 return -ENOENT;
 625         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 626 }
 627
 628 /*
 629  * Create a new subvolume below @parent.  This is largely modeled after
 630  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 631  * inside this filesystem so it's quite a bit simpler.
 632  */
 633 static noinline int btrfs_mksubvol(struct path *parent,
 634                                    char *name, int namelen,
 635                                    struct btrfs_root *snap_src,
 636                                    u64 *async_transid, bool readonly)
 637 {
 638         struct inode *dir  = parent->dentry->d_inode;
 639         struct dentry *dentry;
 640         int error;
 641
 642         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
 643
 644         dentry = lookup_one_len(name, parent->dentry, namelen);
 645         error = PTR_ERR(dentry);
 646         if (IS_ERR(dentry))
 647                 goto out_unlock;
 648
 649         error = -EEXIST;
 650         if (dentry->d_inode)
 651                 goto out_dput;
 652
 653         error = mnt_want_write(parent->mnt);
 654         if (error)
 655                 goto out_dput;
 656
 657         error = btrfs_may_create(dir, dentry);
 658         if (error)
 659                 goto out_drop_write;
 660
 661         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 662
 663         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 664                 goto out_up_read;
 665
 666         if (snap_src) {
 667                 error = create_snapshot(snap_src, dentry,
 668                                         name, namelen, async_transid, readonly);
 669         } else {
 670                 error = create_subvol(BTRFS_I(dir)->root, dentry,
 671                                       name, namelen, async_transid);
 672         }
 673         if (!error)
 674                 fsnotify_mkdir(dir, dentry);
 675 out_up_read:
 676         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 677 out_drop_write:
 678         mnt_drop_write(parent->mnt);
 679 out_dput:
 680         dput(dentry);
 681 out_unlock:
 682         mutex_unlock(&dir->i_mutex);
 683         return error;
 684 }
 685
 686 /*
 687  * When we're defragging a range, we don't want to kick it off again
 688  * if it is really just waiting for delalloc to send it down.
 689  * If we find a nice big extent or delalloc range for the bytes in the
 690  * file you want to defrag, we return 0 to let you know to skip this
 691  * part of the file
 692  */
 693 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
 694 {
 695         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 696         struct extent_map *em = NULL;
 697         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 698         u64 end;
 699
 700         read_lock(&em_tree->lock);
 701         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 702         read_unlock(&em_tree->lock);
 703
 704         if (em) {
 705                 end = extent_map_end(em);
 706                 free_extent_map(em);
 707                 if (end - offset > thresh)
 708                         return 0;
 709         }
 710         /* if we already have a nice delalloc here, just stop */
 711         thresh /= 2;
 712         end = count_range_bits(io_tree, &offset, offset + thresh,
 713                                thresh, EXTENT_DELALLOC, 1);
 714         if (end >= thresh)
 715                 return 0;
 716         return 1;
 717 }
 718
 719 /*
 720  * helper function to walk through a file and find extents
 721  * newer than a specific transid, and smaller than thresh.
 722  *
 723  * This is used by the defragging code to find new and small
 724  * extents
 725  */
 726 static int find_new_extents(struct btrfs_root *root,
 727                             struct inode *inode, u64 newer_than,
 728                             u64 *off, int thresh)
 729 {
 730         struct btrfs_path *path;
 731         struct btrfs_key min_key;
 732         struct btrfs_key max_key;
 733         struct extent_buffer *leaf;
 734         struct btrfs_file_extent_item *extent;
 735         int type;
 736         int ret;
 737         u64 ino = btrfs_ino(inode);
 738
 739         path = btrfs_alloc_path();
 740         if (!path)
 741                 return -ENOMEM;
 742
 743         min_key.objectid = ino;
 744         min_key.type = BTRFS_EXTENT_DATA_KEY;
 745         min_key.offset = *off;
 746
 747         max_key.objectid = ino;
 748         max_key.type = (u8)-1;
 749         max_key.offset = (u64)-1;
 750
 751         path->keep_locks = 1;
 752
 753         while(1) {
 754                 ret = btrfs_search_forward(root, &min_key, &max_key,
 755                                            path, 0, newer_than);
 756                 if (ret != 0)
 757                         goto none;
 758                 if (min_key.objectid != ino)
 759                         goto none;
 760                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 761                         goto none;
 762
 763                 leaf = path->nodes[0];
 764                 extent = btrfs_item_ptr(leaf, path->slots[0],
 765                                         struct btrfs_file_extent_item);
 766
 767                 type = btrfs_file_extent_type(leaf, extent);
 768                 if (type == BTRFS_FILE_EXTENT_REG &&
 769                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 770                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 771                         *off = min_key.offset;
 772                         btrfs_free_path(path);
 773                         return 0;
 774                 }
 775
 776                 if (min_key.offset == (u64)-1)
 777                         goto none;
 778
 779                 min_key.offset++;
 780                 btrfs_release_path(path);
 781         }
 782 none:
 783         btrfs_free_path(path);
 784         return -ENOENT;
 785 }
 786
 787 /*
 788  * Validaty check of prev em and next em:
 789  * 1) no prev/next em
 790  * 2) prev/next em is an hole/inline extent
 791  */
 792 static int check_adjacent_extents(struct inode *inode, struct extent_map *em)
 793 {
 794         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 795         struct extent_map *prev = NULL, *next = NULL;
 796         int ret = 0;
 797
 798         read_lock(&em_tree->lock);
 799         prev = lookup_extent_mapping(em_tree, em->start - 1, (u64)-1);
 800         next = lookup_extent_mapping(em_tree, em->start + em->len, (u64)-1);
 801         read_unlock(&em_tree->lock);
 802
 803         if ((!prev || prev->block_start >= EXTENT_MAP_LAST_BYTE) &&
 804             (!next || next->block_start >= EXTENT_MAP_LAST_BYTE))
 805                 ret = 1;
 806         free_extent_map(prev);
 807         free_extent_map(next);
 808
 809         return ret;
 810 }
 811
 812 static int should_defrag_range(struct inode *inode, u64 start, u64 len,
 813                                int thresh, u64 *last_len, u64 *skip,
 814                                u64 *defrag_end)
 815 {
 816         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 817         struct extent_map *em = NULL;
 818         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 819         int ret = 1;
 820
 821         /*
 822          * make sure that once we start defragging an extent, we keep on
 823          * defragging it
 824          */
 825         if (start < *defrag_end)
 826                 return 1;
 827
 828         *skip = 0;
 829
 830         /*
 831          * hopefully we have this extent in the tree already, try without
 832          * the full extent lock
 833          */
 834         read_lock(&em_tree->lock);
 835         em = lookup_extent_mapping(em_tree, start, len);
 836         read_unlock(&em_tree->lock);
 837
 838         if (!em) {
 839                 /* get the big lock and read metadata off disk */
 840                 lock_extent(io_tree, start, start + len - 1);
 841                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 842                 unlock_extent(io_tree, start, start + len - 1);
 843
 844                 if (IS_ERR(em))
 845                         return 0;
 846         }
 847
 848         /* this will cover holes, and inline extents */
 849         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
 850                 ret = 0;
 851                 goto out;
 852         }
 853
 854         /* If we have nothing to merge with us, just skip. */
 855         if (check_adjacent_extents(inode, em)) {
 856                 ret = 0;
 857                 goto out;
 858         }
 859
 860         /*
 861          * we hit a real extent, if it is big don't bother defragging it again
 862          */
 863         if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
 864                 ret = 0;
 865
 866 out:
 867         /*
 868          * last_len ends up being a counter of how many bytes we've defragged.
 869          * every time we choose not to defrag an extent, we reset *last_len
 870          * so that the next tiny extent will force a defrag.
 871          *
 872          * The end result of this is that tiny extents before a single big
 873          * extent will force at least part of that big extent to be defragged.
 874          */
 875         if (ret) {
 876                 *defrag_end = extent_map_end(em);
 877         } else {
 878                 *last_len = 0;
 879                 *skip = extent_map_end(em);
 880                 *defrag_end = 0;
 881         }
 882
 883         free_extent_map(em);
 884         return ret;
 885 }
 886
 887 /*
 888  * it doesn't do much good to defrag one or two pages
 889  * at a time.  This pulls in a nice chunk of pages
 890  * to COW and defrag.
 891  *
 892  * It also makes sure the delalloc code has enough
 893  * dirty data to avoid making new small extents as part
 894  * of the defrag
 895  *
 896  * It's a good idea to start RA on this range
 897  * before calling this.
 898  */
 899 static int cluster_pages_for_defrag(struct inode *inode,
 900                                     struct page **pages,
 901                                     unsigned long start_index,
 902                                     int num_pages)
 903 {
 904         unsigned long file_end;
 905         u64 isize = i_size_read(inode);
 906         u64 page_start;
 907         u64 page_end;
 908         u64 page_cnt;
 909         int ret;
 910         int i;
 911         int i_done;
 912         struct btrfs_ordered_extent *ordered;
 913         struct extent_state *cached_state = NULL;
 914         struct extent_io_tree *tree;
 915         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
 916
 917         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
 918         if (!isize || start_index > file_end)
 919                 return 0;
 920
 921         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
 922
 923         ret = btrfs_delalloc_reserve_space(inode,
 924                                            page_cnt << PAGE_CACHE_SHIFT);
 925         if (ret)
 926                 return ret;
 927         i_done = 0;
 928         tree = &BTRFS_I(inode)->io_tree;
 929
 930         /* step one, lock all the pages */
 931         for (i = 0; i < page_cnt; i++) {
 932                 struct page *page;
 933 again:
 934                 page = find_or_create_page(inode->i_mapping,
 935                                            start_index + i, mask);
 936                 if (!page)
 937                         break;
 938
 939                 page_start = page_offset(page);
 940                 page_end = page_start + PAGE_CACHE_SIZE - 1;
 941                 while (1) {
 942                         lock_extent(tree, page_start, page_end);
 943                         ordered = btrfs_lookup_ordered_extent(inode,
 944                                                               page_start);
 945                         unlock_extent(tree, page_start, page_end);
 946                         if (!ordered)
 947                                 break;
 948
 949                         unlock_page(page);
 950                         btrfs_start_ordered_extent(inode, ordered, 1);
 951                         btrfs_put_ordered_extent(ordered);
 952                         lock_page(page);
 953                         /*
 954                          * we unlocked the page above, so we need check if
 955                          * it was released or not.
 956                          */
 957                         if (page->mapping != inode->i_mapping) {
 958                                 unlock_page(page);
 959                                 page_cache_release(page);
 960                                 goto again;
 961                         }
 962                 }
 963
 964                 if (!PageUptodate(page)) {
 965                         btrfs_readpage(NULL, page);
 966                         lock_page(page);
 967                         if (!PageUptodate(page)) {
 968                                 unlock_page(page);
 969                                 page_cache_release(page);
 970                                 ret = -EIO;
 971                                 break;
 972                         }
 973                 }
 974
 975                 if (page->mapping != inode->i_mapping) {
 976                         unlock_page(page);
 977                         page_cache_release(page);
 978                         goto again;
 979                 }
 980
 981                 pages[i] = page;
 982                 i_done++;
 983         }
 984         if (!i_done || ret)
 985                 goto out;
 986
 987         if (!(inode->i_sb->s_flags & MS_ACTIVE))
 988                 goto out;
 989
 990         /*
 991          * so now we have a nice long stream of locked
 992          * and up to date pages, lets wait on them
 993          */
 994         for (i = 0; i < i_done; i++)
 995                 wait_on_page_writeback(pages[i]);
 996
 997         page_start = page_offset(pages[0]);
 998         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
 999
1000         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1001                          page_start, page_end - 1, 0, &cached_state);
1002         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1003                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1004                           EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
1005                           GFP_NOFS);
1006
1007         if (i_done != page_cnt) {
1008                 spin_lock(&BTRFS_I(inode)->lock);
1009                 BTRFS_I(inode)->outstanding_extents++;
1010                 spin_unlock(&BTRFS_I(inode)->lock);
1011                 btrfs_delalloc_release_space(inode,
1012                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1013         }
1014
1015
1016         btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
1017                                   &cached_state);
1018
1019         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1020                              page_start, page_end - 1, &cached_state,
1021                              GFP_NOFS);
1022
1023         for (i = 0; i < i_done; i++) {
1024                 clear_page_dirty_for_io(pages[i]);
1025                 ClearPageChecked(pages[i]);
1026                 set_page_extent_mapped(pages[i]);
1027                 set_page_dirty(pages[i]);
1028                 unlock_page(pages[i]);
1029                 page_cache_release(pages[i]);
1030         }
1031         return i_done;
1032 out:
1033         for (i = 0; i < i_done; i++) {
1034                 unlock_page(pages[i]);
1035                 page_cache_release(pages[i]);
1036         }
1037         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1038         return ret;
1039
1040 }
1041
1042 int btrfs_defrag_file(struct inode *inode, struct file *file,
1043                       struct btrfs_ioctl_defrag_range_args *range,
1044                       u64 newer_than, unsigned long max_to_defrag)
1045 {
1046         struct btrfs_root *root = BTRFS_I(inode)->root;
1047         struct btrfs_super_block *disk_super;
1048         struct file_ra_state *ra = NULL;
1049         unsigned long last_index;
1050         u64 isize = i_size_read(inode);
1051         u64 features;
1052         u64 last_len = 0;
1053         u64 skip = 0;
1054         u64 defrag_end = 0;
1055         u64 newer_off = range->start;
1056         unsigned long i;
1057         unsigned long ra_index = 0;
1058         int ret;
1059         int defrag_count = 0;
1060         int compress_type = BTRFS_COMPRESS_ZLIB;
1061         int extent_thresh = range->extent_thresh;
1062         int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1063         int cluster = max_cluster;
1064         u64 new_align = ~((u64)128 * 1024 - 1);
1065         struct page **pages = NULL;
1066
1067         if (extent_thresh == 0)
1068                 extent_thresh = 256 * 1024;
1069
1070         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1071                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1072                         return -EINVAL;
1073                 if (range->compress_type)
1074                         compress_type = range->compress_type;
1075         }
1076
1077         if (isize == 0)
1078                 return 0;
1079
1080         /*
1081          * if we were not given a file, allocate a readahead
1082          * context
1083          */
1084         if (!file) {
1085                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1086                 if (!ra)
1087                         return -ENOMEM;
1088                 file_ra_state_init(ra, inode->i_mapping);
1089         } else {
1090                 ra = &file->f_ra;
1091         }
1092
1093         pages = kmalloc(sizeof(struct page *) * max_cluster,
1094                         GFP_NOFS);
1095         if (!pages) {
1096                 ret = -ENOMEM;
1097                 goto out_ra;
1098         }
1099
1100         /* find the last page to defrag */
1101         if (range->start + range->len > range->start) {
1102                 last_index = min_t(u64, isize - 1,
1103                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1104         } else {
1105                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1106         }
1107
1108         if (newer_than) {
1109                 ret = find_new_extents(root, inode, newer_than,
1110                                        &newer_off, 64 * 1024);
1111                 if (!ret) {
1112                         range->start = newer_off;
1113                         /*
1114                          * we always align our defrag to help keep
1115                          * the extents in the file evenly spaced
1116                          */
1117                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1118                 } else
1119                         goto out_ra;
1120         } else {
1121                 i = range->start >> PAGE_CACHE_SHIFT;
1122         }
1123         if (!max_to_defrag)
1124                 max_to_defrag = last_index + 1;
1125
1126         /*
1127          * make writeback starts from i, so the defrag range can be
1128          * written sequentially.
1129          */
1130         if (i < inode->i_mapping->writeback_index)
1131                 inode->i_mapping->writeback_index = i;
1132
1133         while (i <= last_index && defrag_count < max_to_defrag &&
1134                (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1135                 PAGE_CACHE_SHIFT)) {
1136                 /*
1137                  * make sure we stop running if someone unmounts
1138                  * the FS
1139                  */
1140                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1141                         break;
1142
1143                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1144                                          PAGE_CACHE_SIZE, extent_thresh,
1145                                          &last_len, &skip, &defrag_end)) {
1146                         unsigned long next;
1147                         /*
1148                          * the should_defrag function tells us how much to skip
1149                          * bump our counter by the suggested amount
1150                          */
1151                         next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1152                         i = max(i + 1, next);
1153                         continue;
1154                 }
1155
1156                 if (!newer_than) {
1157                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1158                                    PAGE_CACHE_SHIFT) - i;
1159                         cluster = min(cluster, max_cluster);
1160                 } else {
1161                         cluster = max_cluster;
1162                 }
1163
1164                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1165                         BTRFS_I(inode)->force_compress = compress_type;
1166
1167                 if (i + cluster > ra_index) {
1168                         ra_index = max(i, ra_index);
1169                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1170                                        cluster);
1171                         ra_index += max_cluster;
1172                 }
1173
1174                 mutex_lock(&inode->i_mutex);
1175                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1176                 if (ret < 0) {
1177                         mutex_unlock(&inode->i_mutex);
1178                         goto out_ra;
1179                 }
1180
1181                 defrag_count += ret;
1182                 balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1183                 mutex_unlock(&inode->i_mutex);
1184
1185                 if (newer_than) {
1186                         if (newer_off == (u64)-1)
1187                                 break;
1188
1189                         if (ret > 0)
1190                                 i += ret;
1191
1192                         newer_off = max(newer_off + 1,
1193                                         (u64)i << PAGE_CACHE_SHIFT);
1194
1195                         ret = find_new_extents(root, inode,
1196                                                newer_than, &newer_off,
1197                                                64 * 1024);
1198                         if (!ret) {
1199                                 range->start = newer_off;
1200                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1201                         } else {
1202                                 break;
1203                         }
1204                 } else {
1205                         if (ret > 0) {
1206                                 i += ret;
1207                                 last_len += ret << PAGE_CACHE_SHIFT;
1208                         } else {
1209                                 i++;
1210                                 last_len = 0;
1211                         }
1212                 }
1213         }
1214
1215         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1216                 filemap_flush(inode->i_mapping);
1217
1218         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1219                 /* the filemap_flush will queue IO into the worker threads, but
1220                  * we have to make sure the IO is actually started and that
1221                  * ordered extents get created before we return
1222                  */
1223                 atomic_inc(&root->fs_info->async_submit_draining);
1224                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1225                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1226                         wait_event(root->fs_info->async_submit_wait,
1227                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1228                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1229                 }
1230                 atomic_dec(&root->fs_info->async_submit_draining);
1231
1232                 mutex_lock(&inode->i_mutex);
1233                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1234                 mutex_unlock(&inode->i_mutex);
1235         }
1236
1237         disk_super = root->fs_info->super_copy;
1238         features = btrfs_super_incompat_flags(disk_super);
1239         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1240                 features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1241                 btrfs_set_super_incompat_flags(disk_super, features);
1242         }
1243
1244         ret = defrag_count;
1245
1246 out_ra:
1247         if (!file)
1248                 kfree(ra);
1249         kfree(pages);
1250         return ret;
1251 }
1252
1253 static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1254                                         void __user *arg)
1255 {
1256         u64 new_size;
1257         u64 old_size;
1258         u64 devid = 1;
1259         struct btrfs_ioctl_vol_args *vol_args;
1260         struct btrfs_trans_handle *trans;
1261         struct btrfs_device *device = NULL;
1262         char *sizestr;
1263         char *devstr = NULL;
1264         int ret = 0;
1265         int mod = 0;
1266
1267         if (root->fs_info->sb->s_flags & MS_RDONLY)
1268                 return -EROFS;
1269
1270         if (!capable(CAP_SYS_ADMIN))
1271                 return -EPERM;
1272
1273         mutex_lock(&root->fs_info->volume_mutex);
1274         if (root->fs_info->balance_ctl) {
1275                 printk(KERN_INFO "btrfs: balance in progress\n");
1276                 ret = -EINVAL;
1277                 goto out;
1278         }
1279
1280         vol_args = memdup_user(arg, sizeof(*vol_args));
1281         if (IS_ERR(vol_args)) {
1282                 ret = PTR_ERR(vol_args);
1283                 goto out;
1284         }
1285
1286         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1287
1288         sizestr = vol_args->name;
1289         devstr = strchr(sizestr, ':');
1290         if (devstr) {
1291                 char *end;
1292                 sizestr = devstr + 1;
1293                 *devstr = '\0';
1294                 devstr = vol_args->name;
1295                 devid = simple_strtoull(devstr, &end, 10);
1296                 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1297                        (unsigned long long)devid);
1298         }
1299         device = btrfs_find_device(root, devid, NULL, NULL);
1300         if (!device) {
1301                 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1302                        (unsigned long long)devid);
1303                 ret = -EINVAL;
1304                 goto out_free;
1305         }
1306         if (!strcmp(sizestr, "max"))
1307                 new_size = device->bdev->bd_inode->i_size;
1308         else {
1309                 if (sizestr[0] == '-') {
1310                         mod = -1;
1311                         sizestr++;
1312                 } else if (sizestr[0] == '+') {
1313                         mod = 1;
1314                         sizestr++;
1315                 }
1316                 new_size = memparse(sizestr, NULL);
1317                 if (new_size == 0) {
1318                         ret = -EINVAL;
1319                         goto out_free;
1320                 }
1321         }
1322
1323         old_size = device->total_bytes;
1324
1325         if (mod < 0) {
1326                 if (new_size > old_size) {
1327                         ret = -EINVAL;
1328                         goto out_free;
1329                 }
1330                 new_size = old_size - new_size;
1331         } else if (mod > 0) {
1332                 new_size = old_size + new_size;
1333         }
1334
1335         if (new_size < 256 * 1024 * 1024) {
1336                 ret = -EINVAL;
1337                 goto out_free;
1338         }
1339         if (new_size > device->bdev->bd_inode->i_size) {
1340                 ret = -EFBIG;
1341                 goto out_free;
1342         }
1343
1344         do_div(new_size, root->sectorsize);
1345         new_size *= root->sectorsize;
1346
1347         printk(KERN_INFO "btrfs: new size for %s is %llu\n",
1348                 device->name, (unsigned long long)new_size);
1349
1350         if (new_size > old_size) {
1351                 trans = btrfs_start_transaction(root, 0);
1352                 if (IS_ERR(trans)) {
1353                         ret = PTR_ERR(trans);
1354                         goto out_free;
1355                 }
1356                 ret = btrfs_grow_device(trans, device, new_size);
1357                 btrfs_commit_transaction(trans, root);
1358         } else if (new_size < old_size) {
1359                 ret = btrfs_shrink_device(device, new_size);
1360         }
1361
1362 out_free:
1363         kfree(vol_args);
1364 out:
1365         mutex_unlock(&root->fs_info->volume_mutex);
1366         return ret;
1367 }
1368
1369 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1370                                                     char *name,
1371                                                     unsigned long fd,
1372                                                     int subvol,
1373                                                     u64 *transid,
1374                                                     bool readonly)
1375 {
1376         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1377         struct file *src_file;
1378         int namelen;
1379         int ret = 0;
1380
1381         if (root->fs_info->sb->s_flags & MS_RDONLY)
1382                 return -EROFS;
1383
1384         namelen = strlen(name);
1385         if (strchr(name, '/')) {
1386                 ret = -EINVAL;
1387                 goto out;
1388         }
1389
1390         if (name[0] == '.' &&
1391            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1392                 ret = -EEXIST;
1393                 goto out;
1394         }
1395
1396         if (subvol) {
1397                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1398                                      NULL, transid, readonly);
1399         } else {
1400                 struct inode *src_inode;
1401                 src_file = fget(fd);
1402                 if (!src_file) {
1403                         ret = -EINVAL;
1404                         goto out;
1405                 }
1406
1407                 src_inode = src_file->f_path.dentry->d_inode;
1408                 if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1409                         printk(KERN_INFO "btrfs: Snapshot src from "
1410                                "another FS\n");
1411                         ret = -EINVAL;
1412                         fput(src_file);
1413                         goto out;
1414                 }
1415                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1416                                      BTRFS_I(src_inode)->root,
1417                                      transid, readonly);
1418                 fput(src_file);
1419         }
1420 out:
1421         return ret;
1422 }
1423
1424 static noinline int btrfs_ioctl_snap_create(struct file *file,
1425                                             void __user *arg, int subvol)
1426 {
1427         struct btrfs_ioctl_vol_args *vol_args;
1428         int ret;
1429
1430         vol_args = memdup_user(arg, sizeof(*vol_args));
1431         if (IS_ERR(vol_args))
1432                 return PTR_ERR(vol_args);
1433         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1434
1435         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1436                                               vol_args->fd, subvol,
1437                                               NULL, false);
1438
1439         kfree(vol_args);
1440         return ret;
1441 }
1442
1443 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1444                                                void __user *arg, int subvol)
1445 {
1446         struct btrfs_ioctl_vol_args_v2 *vol_args;
1447         int ret;
1448         u64 transid = 0;
1449         u64 *ptr = NULL;
1450         bool readonly = false;
1451
1452         vol_args = memdup_user(arg, sizeof(*vol_args));
1453         if (IS_ERR(vol_args))
1454                 return PTR_ERR(vol_args);
1455         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1456
1457         if (vol_args->flags &
1458             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1459                 ret = -EOPNOTSUPP;
1460                 goto out;
1461         }
1462
1463         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1464                 ptr = &transid;
1465         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1466                 readonly = true;
1467
1468         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1469                                               vol_args->fd, subvol,
1470                                               ptr, readonly);
1471
1472         if (ret == 0 && ptr &&
1473             copy_to_user(arg +
1474                          offsetof(struct btrfs_ioctl_vol_args_v2,
1475                                   transid), ptr, sizeof(*ptr)))
1476                 ret = -EFAULT;
1477 out:
1478         kfree(vol_args);
1479         return ret;
1480 }
1481
1482 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1483                                                 void __user *arg)
1484 {
1485         struct inode *inode = fdentry(file)->d_inode;
1486         struct btrfs_root *root = BTRFS_I(inode)->root;
1487         int ret = 0;
1488         u64 flags = 0;
1489
1490         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1491                 return -EINVAL;
1492
1493         down_read(&root->fs_info->subvol_sem);
1494         if (btrfs_root_readonly(root))
1495                 flags |= BTRFS_SUBVOL_RDONLY;
1496         up_read(&root->fs_info->subvol_sem);
1497
1498         if (copy_to_user(arg, &flags, sizeof(flags)))
1499                 ret = -EFAULT;
1500
1501         return ret;
1502 }
1503
1504 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1505                                               void __user *arg)
1506 {
1507         struct inode *inode = fdentry(file)->d_inode;
1508         struct btrfs_root *root = BTRFS_I(inode)->root;
1509         struct btrfs_trans_handle *trans;
1510         u64 root_flags;
1511         u64 flags;
1512         int ret = 0;
1513
1514         if (root->fs_info->sb->s_flags & MS_RDONLY)
1515                 return -EROFS;
1516
1517         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1518                 return -EINVAL;
1519
1520         if (copy_from_user(&flags, arg, sizeof(flags)))
1521                 return -EFAULT;
1522
1523         if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1524                 return -EINVAL;
1525
1526         if (flags & ~BTRFS_SUBVOL_RDONLY)
1527                 return -EOPNOTSUPP;
1528
1529         if (!inode_owner_or_capable(inode))
1530                 return -EACCES;
1531
1532         down_write(&root->fs_info->subvol_sem);
1533
1534         /* nothing to do */
1535         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1536                 goto out;
1537
1538         root_flags = btrfs_root_flags(&root->root_item);
1539         if (flags & BTRFS_SUBVOL_RDONLY)
1540                 btrfs_set_root_flags(&root->root_item,
1541                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1542         else
1543                 btrfs_set_root_flags(&root->root_item,
1544                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1545
1546         trans = btrfs_start_transaction(root, 1);
1547         if (IS_ERR(trans)) {
1548                 ret = PTR_ERR(trans);
1549                 goto out_reset;
1550         }
1551
1552         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1553                                 &root->root_key, &root->root_item);
1554
1555         btrfs_commit_transaction(trans, root);
1556 out_reset:
1557         if (ret)
1558                 btrfs_set_root_flags(&root->root_item, root_flags);
1559 out:
1560         up_write(&root->fs_info->subvol_sem);
1561         return ret;
1562 }
1563
1564 /*
1565  * helper to check if the subvolume references other subvolumes
1566  */
1567 static noinline int may_destroy_subvol(struct btrfs_root *root)
1568 {
1569         struct btrfs_path *path;
1570         struct btrfs_key key;
1571         int ret;
1572
1573         path = btrfs_alloc_path();
1574         if (!path)
1575                 return -ENOMEM;
1576
1577         key.objectid = root->root_key.objectid;
1578         key.type = BTRFS_ROOT_REF_KEY;
1579         key.offset = (u64)-1;
1580
1581         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1582                                 &key, path, 0, 0);
1583         if (ret < 0)
1584                 goto out;
1585         BUG_ON(ret == 0);
1586
1587         ret = 0;
1588         if (path->slots[0] > 0) {
1589                 path->slots[0]--;
1590                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1591                 if (key.objectid == root->root_key.objectid &&
1592                     key.type == BTRFS_ROOT_REF_KEY)
1593                         ret = -ENOTEMPTY;
1594         }
1595 out:
1596         btrfs_free_path(path);
1597         return ret;
1598 }
1599
1600 static noinline int key_in_sk(struct btrfs_key *key,
1601                               struct btrfs_ioctl_search_key *sk)
1602 {
1603         struct btrfs_key test;
1604         int ret;
1605
1606         test.objectid = sk->min_objectid;
1607         test.type = sk->min_type;
1608         test.offset = sk->min_offset;
1609
1610         ret = btrfs_comp_cpu_keys(key, &test);
1611         if (ret < 0)
1612                 return 0;
1613
1614         test.objectid = sk->max_objectid;
1615         test.type = sk->max_type;
1616         test.offset = sk->max_offset;
1617
1618         ret = btrfs_comp_cpu_keys(key, &test);
1619         if (ret > 0)
1620                 return 0;
1621         return 1;
1622 }
1623
1624 static noinline int copy_to_sk(struct btrfs_root *root,
1625                                struct btrfs_path *path,
1626                                struct btrfs_key *key,
1627                                struct btrfs_ioctl_search_key *sk,
1628                                char *buf,
1629                                unsigned long *sk_offset,
1630                                int *num_found)
1631 {
1632         u64 found_transid;
1633         struct extent_buffer *leaf;
1634         struct btrfs_ioctl_search_header sh;
1635         unsigned long item_off;
1636         unsigned long item_len;
1637         int nritems;
1638         int i;
1639         int slot;
1640         int ret = 0;
1641
1642         leaf = path->nodes[0];
1643         slot = path->slots[0];
1644         nritems = btrfs_header_nritems(leaf);
1645
1646         if (btrfs_header_generation(leaf) > sk->max_transid) {
1647                 i = nritems;
1648                 goto advance_key;
1649         }
1650         found_transid = btrfs_header_generation(leaf);
1651
1652         for (i = slot; i < nritems; i++) {
1653                 item_off = btrfs_item_ptr_offset(leaf, i);
1654                 item_len = btrfs_item_size_nr(leaf, i);
1655
1656                 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1657                         item_len = 0;
1658
1659                 if (sizeof(sh) + item_len + *sk_offset >
1660                     BTRFS_SEARCH_ARGS_BUFSIZE) {
1661                         ret = 1;
1662                         goto overflow;
1663                 }
1664
1665                 btrfs_item_key_to_cpu(leaf, key, i);
1666                 if (!key_in_sk(key, sk))
1667                         continue;
1668
1669                 sh.objectid = key->objectid;
1670                 sh.offset = key->offset;
1671                 sh.type = key->type;
1672                 sh.len = item_len;
1673                 sh.transid = found_transid;
1674
1675                 /* copy search result header */
1676                 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1677                 *sk_offset += sizeof(sh);
1678
1679                 if (item_len) {
1680                         char *p = buf + *sk_offset;
1681                         /* copy the item */
1682                         read_extent_buffer(leaf, p,
1683                                            item_off, item_len);
1684                         *sk_offset += item_len;
1685                 }
1686                 (*num_found)++;
1687
1688                 if (*num_found >= sk->nr_items)
1689                         break;
1690         }
1691 advance_key:
1692         ret = 0;
1693         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1694                 key->offset++;
1695         else if (key->type < (u8)-1 && key->type < sk->max_type) {
1696                 key->offset = 0;
1697                 key->type++;
1698         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1699                 key->offset = 0;
1700                 key->type = 0;
1701                 key->objectid++;
1702         } else
1703                 ret = 1;
1704 overflow:
1705         return ret;
1706 }
1707
1708 static noinline int search_ioctl(struct inode *inode,
1709                                  struct btrfs_ioctl_search_args *args)
1710 {
1711         struct btrfs_root *root;
1712         struct btrfs_key key;
1713         struct btrfs_key max_key;
1714         struct btrfs_path *path;
1715         struct btrfs_ioctl_search_key *sk = &args->key;
1716         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1717         int ret;
1718         int num_found = 0;
1719         unsigned long sk_offset = 0;
1720
1721         path = btrfs_alloc_path();
1722         if (!path)
1723                 return -ENOMEM;
1724
1725         if (sk->tree_id == 0) {
1726                 /* search the root of the inode that was passed */
1727                 root = BTRFS_I(inode)->root;
1728         } else {
1729                 key.objectid = sk->tree_id;
1730                 key.type = BTRFS_ROOT_ITEM_KEY;
1731                 key.offset = (u64)-1;
1732                 root = btrfs_read_fs_root_no_name(info, &key);
1733                 if (IS_ERR(root)) {
1734                         printk(KERN_ERR "could not find root %llu\n",
1735                                sk->tree_id);
1736                         btrfs_free_path(path);
1737                         return -ENOENT;
1738                 }
1739         }
1740
1741         key.objectid = sk->min_objectid;
1742         key.type = sk->min_type;
1743         key.offset = sk->min_offset;
1744
1745         max_key.objectid = sk->max_objectid;
1746         max_key.type = sk->max_type;
1747         max_key.offset = sk->max_offset;
1748
1749         path->keep_locks = 1;
1750
1751         while(1) {
1752                 ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1753                                            sk->min_transid);
1754                 if (ret != 0) {
1755                         if (ret > 0)
1756                                 ret = 0;
1757                         goto err;
1758                 }
1759                 ret = copy_to_sk(root, path, &key, sk, args->buf,
1760                                  &sk_offset, &num_found);
1761                 btrfs_release_path(path);
1762                 if (ret || num_found >= sk->nr_items)
1763                         break;
1764
1765         }
1766         ret = 0;
1767 err:
1768         sk->nr_items = num_found;
1769         btrfs_free_path(path);
1770         return ret;
1771 }
1772
1773 static noinline int btrfs_ioctl_tree_search(struct file *file,
1774                                            void __user *argp)
1775 {
1776          struct btrfs_ioctl_search_args *args;
1777          struct inode *inode;
1778          int ret;
1779
1780         if (!capable(CAP_SYS_ADMIN))
1781                 return -EPERM;
1782
1783         args = memdup_user(argp, sizeof(*args));
1784         if (IS_ERR(args))
1785                 return PTR_ERR(args);
1786
1787         inode = fdentry(file)->d_inode;
1788         ret = search_ioctl(inode, args);
1789         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1790                 ret = -EFAULT;
1791         kfree(args);
1792         return ret;
1793 }
1794
1795 /*
1796  * Search INODE_REFs to identify path name of 'dirid' directory
1797  * in a 'tree_id' tree. and sets path name to 'name'.
1798  */
1799 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1800                                 u64 tree_id, u64 dirid, char *name)
1801 {
1802         struct btrfs_root *root;
1803         struct btrfs_key key;
1804         char *ptr;
1805         int ret = -1;
1806         int slot;
1807         int len;
1808         int total_len = 0;
1809         struct btrfs_inode_ref *iref;
1810         struct extent_buffer *l;
1811         struct btrfs_path *path;
1812
1813         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1814                 name[0]='\0';
1815                 return 0;
1816         }
1817
1818         path = btrfs_alloc_path();
1819         if (!path)
1820                 return -ENOMEM;
1821
1822         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1823
1824         key.objectid = tree_id;
1825         key.type = BTRFS_ROOT_ITEM_KEY;
1826         key.offset = (u64)-1;
1827         root = btrfs_read_fs_root_no_name(info, &key);
1828         if (IS_ERR(root)) {
1829                 printk(KERN_ERR "could not find root %llu\n", tree_id);
1830                 ret = -ENOENT;
1831                 goto out;
1832         }
1833
1834         key.objectid = dirid;
1835         key.type = BTRFS_INODE_REF_KEY;
1836         key.offset = (u64)-1;
1837
1838         while(1) {
1839                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1840                 if (ret < 0)
1841                         goto out;
1842
1843                 l = path->nodes[0];
1844                 slot = path->slots[0];
1845                 if (ret > 0 && slot > 0)
1846                         slot--;
1847                 btrfs_item_key_to_cpu(l, &key, slot);
1848
1849                 if (ret > 0 && (key.objectid != dirid ||
1850                                 key.type != BTRFS_INODE_REF_KEY)) {
1851                         ret = -ENOENT;
1852                         goto out;
1853                 }
1854
1855                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1856                 len = btrfs_inode_ref_name_len(l, iref);
1857                 ptr -= len + 1;
1858                 total_len += len + 1;
1859                 if (ptr < name)
1860                         goto out;
1861
1862                 *(ptr + len) = '/';
1863                 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1864
1865                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1866                         break;
1867
1868                 btrfs_release_path(path);
1869                 key.objectid = key.offset;
1870                 key.offset = (u64)-1;
1871                 dirid = key.objectid;
1872         }
1873         if (ptr < name)
1874                 goto out;
1875         memmove(name, ptr, total_len);
1876         name[total_len]='\0';
1877         ret = 0;
1878 out:
1879         btrfs_free_path(path);
1880         return ret;
1881 }
1882
1883 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1884                                            void __user *argp)
1885 {
1886          struct btrfs_ioctl_ino_lookup_args *args;
1887          struct inode *inode;
1888          int ret;
1889
1890         if (!capable(CAP_SYS_ADMIN))
1891                 return -EPERM;
1892
1893         args = memdup_user(argp, sizeof(*args));
1894         if (IS_ERR(args))
1895                 return PTR_ERR(args);
1896
1897         inode = fdentry(file)->d_inode;
1898
1899         if (args->treeid == 0)
1900                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
1901
1902         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1903                                         args->treeid, args->objectid,
1904                                         args->name);
1905
1906         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1907                 ret = -EFAULT;
1908
1909         kfree(args);
1910         return ret;
1911 }
1912
1913 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1914                                              void __user *arg)
1915 {
1916         struct dentry *parent = fdentry(file);
1917         struct dentry *dentry;
1918         struct inode *dir = parent->d_inode;
1919         struct inode *inode;
1920         struct btrfs_root *root = BTRFS_I(dir)->root;
1921         struct btrfs_root *dest = NULL;
1922         struct btrfs_ioctl_vol_args *vol_args;
1923         struct btrfs_trans_handle *trans;
1924         int namelen;
1925         int ret;
1926         int err = 0;
1927
1928         vol_args = memdup_user(arg, sizeof(*vol_args));
1929         if (IS_ERR(vol_args))
1930                 return PTR_ERR(vol_args);
1931
1932         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1933         namelen = strlen(vol_args->name);
1934         if (strchr(vol_args->name, '/') ||
1935             strncmp(vol_args->name, "..", namelen) == 0) {
1936                 err = -EINVAL;
1937                 goto out;
1938         }
1939
1940         err = mnt_want_write_file(file);
1941         if (err)
1942                 goto out;
1943
1944         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1945         dentry = lookup_one_len(vol_args->name, parent, namelen);
1946         if (IS_ERR(dentry)) {
1947                 err = PTR_ERR(dentry);
1948                 goto out_unlock_dir;
1949         }
1950
1951         if (!dentry->d_inode) {
1952                 err = -ENOENT;
1953                 goto out_dput;
1954         }
1955
1956         inode = dentry->d_inode;
1957         dest = BTRFS_I(inode)->root;
1958         if (!capable(CAP_SYS_ADMIN)){
1959                 /*
1960                  * Regular user.  Only allow this with a special mount
1961                  * option, when the user has write+exec access to the
1962                  * subvol root, and when rmdir(2) would have been
1963                  * allowed.
1964                  *
1965                  * Note that this is _not_ check that the subvol is
1966                  * empty or doesn't contain data that we wouldn't
1967                  * otherwise be able to delete.
1968                  *
1969                  * Users who want to delete empty subvols should try
1970                  * rmdir(2).
1971                  */
1972                 err = -EPERM;
1973                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1974                         goto out_dput;
1975
1976                 /*
1977                  * Do not allow deletion if the parent dir is the same
1978                  * as the dir to be deleted.  That means the ioctl
1979                  * must be called on the dentry referencing the root
1980                  * of the subvol, not a random directory contained
1981                  * within it.
1982                  */
1983                 err = -EINVAL;
1984                 if (root == dest)
1985                         goto out_dput;
1986
1987                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
1988                 if (err)
1989                         goto out_dput;
1990
1991                 /* check if subvolume may be deleted by a non-root user */
1992                 err = btrfs_may_delete(dir, dentry, 1);
1993                 if (err)
1994                         goto out_dput;
1995         }
1996
1997         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1998                 err = -EINVAL;
1999                 goto out_dput;
2000         }
2001
2002         mutex_lock(&inode->i_mutex);
2003         err = d_invalidate(dentry);
2004         if (err)
2005                 goto out_unlock;
2006
2007         down_write(&root->fs_info->subvol_sem);
2008
2009         err = may_destroy_subvol(dest);
2010         if (err)
2011                 goto out_up_write;
2012
2013         trans = btrfs_start_transaction(root, 0);
2014         if (IS_ERR(trans)) {
2015                 err = PTR_ERR(trans);
2016                 goto out_up_write;
2017         }
2018         trans->block_rsv = &root->fs_info->global_block_rsv;
2019
2020         ret = btrfs_unlink_subvol(trans, root, dir,
2021                                 dest->root_key.objectid,
2022                                 dentry->d_name.name,
2023                                 dentry->d_name.len);
2024         if (ret) {
2025                 err = ret;
2026                 btrfs_abort_transaction(trans, root, ret);
2027                 goto out_end_trans;
2028         }
2029
2030         btrfs_record_root_in_trans(trans, dest);
2031
2032         memset(&dest->root_item.drop_progress, 0,
2033                 sizeof(dest->root_item.drop_progress));
2034         dest->root_item.drop_level = 0;
2035         btrfs_set_root_refs(&dest->root_item, 0);
2036
2037         if (!xchg(&dest->orphan_item_inserted, 1)) {
2038                 ret = btrfs_insert_orphan_item(trans,
2039                                         root->fs_info->tree_root,
2040                                         dest->root_key.objectid);
2041                 if (ret) {
2042                         btrfs_abort_transaction(trans, root, ret);
2043                         err = ret;
2044                         goto out_end_trans;
2045                 }
2046         }
2047 out_end_trans:
2048         ret = btrfs_end_transaction(trans, root);
2049         if (ret && !err)
2050                 err = ret;
2051         inode->i_flags |= S_DEAD;
2052 out_up_write:
2053         up_write(&root->fs_info->subvol_sem);
2054 out_unlock:
2055         mutex_unlock(&inode->i_mutex);
2056         if (!err) {
2057                 shrink_dcache_sb(root->fs_info->sb);
2058                 btrfs_invalidate_inodes(dest);
2059                 d_delete(dentry);
2060         }
2061 out_dput:
2062         dput(dentry);
2063 out_unlock_dir:
2064         mutex_unlock(&dir->i_mutex);
2065         mnt_drop_write_file(file);
2066 out:
2067         kfree(vol_args);
2068         return err;
2069 }
2070
2071 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2072 {
2073         struct inode *inode = fdentry(file)->d_inode;
2074         struct btrfs_root *root = BTRFS_I(inode)->root;
2075         struct btrfs_ioctl_defrag_range_args *range;
2076         int ret;
2077
2078         if (btrfs_root_readonly(root))
2079                 return -EROFS;
2080
2081         ret = mnt_want_write_file(file);
2082         if (ret)
2083                 return ret;
2084
2085         switch (inode->i_mode & S_IFMT) {
2086         case S_IFDIR:
2087                 if (!capable(CAP_SYS_ADMIN)) {
2088                         ret = -EPERM;
2089                         goto out;
2090                 }
2091                 ret = btrfs_defrag_root(root, 0);
2092                 if (ret)
2093                         goto out;
2094                 ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
2095                 break;
2096         case S_IFREG:
2097                 if (!(file->f_mode & FMODE_WRITE)) {
2098                         ret = -EINVAL;
2099                         goto out;
2100                 }
2101
2102                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2103                 if (!range) {
2104                         ret = -ENOMEM;
2105                         goto out;
2106                 }
2107
2108                 if (argp) {
2109                         if (copy_from_user(range, argp,
2110                                            sizeof(*range))) {
2111                                 ret = -EFAULT;
2112                                 kfree(range);
2113                                 goto out;
2114                         }
2115                         /* compression requires us to start the IO */
2116                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2117                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2118                                 range->extent_thresh = (u32)-1;
2119                         }
2120                 } else {
2121                         /* the rest are all set to zero by kzalloc */
2122                         range->len = (u64)-1;
2123                 }
2124                 ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2125                                         range, 0, 0);
2126                 if (ret > 0)
2127                         ret = 0;
2128                 kfree(range);
2129                 break;
2130         default:
2131                 ret = -EINVAL;
2132         }
2133 out:
2134         mnt_drop_write_file(file);
2135         return ret;
2136 }
2137
2138 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2139 {
2140         struct btrfs_ioctl_vol_args *vol_args;
2141         int ret;
2142
2143         if (!capable(CAP_SYS_ADMIN))
2144                 return -EPERM;
2145
2146         mutex_lock(&root->fs_info->volume_mutex);
2147         if (root->fs_info->balance_ctl) {
2148                 printk(KERN_INFO "btrfs: balance in progress\n");
2149                 ret = -EINVAL;
2150                 goto out;
2151         }
2152
2153         vol_args = memdup_user(arg, sizeof(*vol_args));
2154         if (IS_ERR(vol_args)) {
2155                 ret = PTR_ERR(vol_args);
2156                 goto out;
2157         }
2158
2159         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2160         ret = btrfs_init_new_device(root, vol_args->name);
2161
2162         kfree(vol_args);
2163 out:
2164         mutex_unlock(&root->fs_info->volume_mutex);
2165         return ret;
2166 }
2167
2168 static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2169 {
2170         struct btrfs_ioctl_vol_args *vol_args;
2171         int ret;
2172
2173         if (!capable(CAP_SYS_ADMIN))
2174                 return -EPERM;
2175
2176         if (root->fs_info->sb->s_flags & MS_RDONLY)
2177                 return -EROFS;
2178
2179         mutex_lock(&root->fs_info->volume_mutex);
2180         if (root->fs_info->balance_ctl) {
2181                 printk(KERN_INFO "btrfs: balance in progress\n");
2182                 ret = -EINVAL;
2183                 goto out;
2184         }
2185
2186         vol_args = memdup_user(arg, sizeof(*vol_args));
2187         if (IS_ERR(vol_args)) {
2188                 ret = PTR_ERR(vol_args);
2189                 goto out;
2190         }
2191
2192         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2193         ret = btrfs_rm_device(root, vol_args->name);
2194
2195         kfree(vol_args);
2196 out:
2197         mutex_unlock(&root->fs_info->volume_mutex);
2198         return ret;
2199 }
2200
2201 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2202 {
2203         struct btrfs_ioctl_fs_info_args *fi_args;
2204         struct btrfs_device *device;
2205         struct btrfs_device *next;
2206         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2207         int ret = 0;
2208
2209         if (!capable(CAP_SYS_ADMIN))
2210                 return -EPERM;
2211
2212         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2213         if (!fi_args)
2214                 return -ENOMEM;
2215
2216         fi_args->num_devices = fs_devices->num_devices;
2217         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2218
2219         mutex_lock(&fs_devices->device_list_mutex);
2220         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2221                 if (device->devid > fi_args->max_id)
2222                         fi_args->max_id = device->devid;
2223         }
2224         mutex_unlock(&fs_devices->device_list_mutex);
2225
2226         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2227                 ret = -EFAULT;
2228
2229         kfree(fi_args);
2230         return ret;
2231 }
2232
2233 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2234 {
2235         struct btrfs_ioctl_dev_info_args *di_args;
2236         struct btrfs_device *dev;
2237         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2238         int ret = 0;
2239         char *s_uuid = NULL;
2240         char empty_uuid[BTRFS_UUID_SIZE] = {0};
2241
2242         if (!capable(CAP_SYS_ADMIN))
2243                 return -EPERM;
2244
2245         di_args = memdup_user(arg, sizeof(*di_args));
2246         if (IS_ERR(di_args))
2247                 return PTR_ERR(di_args);
2248
2249         if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2250                 s_uuid = di_args->uuid;
2251
2252         mutex_lock(&fs_devices->device_list_mutex);
2253         dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2254         mutex_unlock(&fs_devices->device_list_mutex);
2255
2256         if (!dev) {
2257                 ret = -ENODEV;
2258                 goto out;
2259         }
2260
2261         di_args->devid = dev->devid;
2262         di_args->bytes_used = dev->bytes_used;
2263         di_args->total_bytes = dev->total_bytes;
2264         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2265         strncpy(di_args->path, dev->name, sizeof(di_args->path));
2266
2267 out:
2268         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2269                 ret = -EFAULT;
2270
2271         kfree(di_args);
2272         return ret;
2273 }
2274
2275 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2276                                        u64 off, u64 olen, u64 destoff)
2277 {
2278         struct inode *inode = fdentry(file)->d_inode;
2279         struct btrfs_root *root = BTRFS_I(inode)->root;
2280         struct file *src_file;
2281         struct inode *src;
2282         struct btrfs_trans_handle *trans;
2283         struct btrfs_path *path;
2284         struct extent_buffer *leaf;
2285         char *buf;
2286         struct btrfs_key key;
2287         u32 nritems;
2288         int slot;
2289         int ret;
2290         u64 len = olen;
2291         u64 bs = root->fs_info->sb->s_blocksize;
2292         u64 hint_byte;
2293
2294         /*
2295          * TODO:
2296          * - split compressed inline extents.  annoying: we need to
2297          *   decompress into destination's address_space (the file offset
2298          *   may change, so source mapping won't do), then recompress (or
2299          *   otherwise reinsert) a subrange.
2300          * - allow ranges within the same file to be cloned (provided
2301          *   they don't overlap)?
2302          */
2303
2304         /* the destination must be opened for writing */
2305         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2306                 return -EINVAL;
2307
2308         if (btrfs_root_readonly(root))
2309                 return -EROFS;
2310
2311         ret = mnt_want_write_file(file);
2312         if (ret)
2313                 return ret;
2314
2315         src_file = fget(srcfd);
2316         if (!src_file) {
2317                 ret = -EBADF;
2318                 goto out_drop_write;
2319         }
2320
2321         src = src_file->f_dentry->d_inode;
2322
2323         ret = -EINVAL;
2324         if (src == inode)
2325                 goto out_fput;
2326
2327         /* the src must be open for reading */
2328         if (!(src_file->f_mode & FMODE_READ))
2329                 goto out_fput;
2330
2331         /* don't make the dst file partly checksummed */
2332         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2333             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2334                 goto out_fput;
2335
2336         ret = -EISDIR;
2337         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2338                 goto out_fput;
2339
2340         ret = -EXDEV;
2341         if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2342                 goto out_fput;
2343
2344         ret = -ENOMEM;
2345         buf = vmalloc(btrfs_level_size(root, 0));
2346         if (!buf)
2347                 goto out_fput;
2348
2349         path = btrfs_alloc_path();
2350         if (!path) {
2351                 vfree(buf);
2352                 goto out_fput;
2353         }
2354         path->reada = 2;
2355
2356         if (inode < src) {
2357                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2358                 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2359         } else {
2360                 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2361                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2362         }
2363
2364         /* determine range to clone */
2365         ret = -EINVAL;
2366         if (off + len > src->i_size || off + len < off)
2367                 goto out_unlock;
2368         if (len == 0)
2369                 olen = len = src->i_size - off;
2370         /* if we extend to eof, continue to block boundary */
2371         if (off + len == src->i_size)
2372                 len = ALIGN(src->i_size, bs) - off;
2373
2374         /* verify the end result is block aligned */
2375         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2376             !IS_ALIGNED(destoff, bs))
2377                 goto out_unlock;
2378
2379         if (destoff > inode->i_size) {
2380                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2381                 if (ret)
2382                         goto out_unlock;
2383         }
2384
2385         /* truncate page cache pages from target inode range */
2386         truncate_inode_pages_range(&inode->i_data, destoff,
2387                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
2388
2389         /* do any pending delalloc/csum calc on src, one way or
2390            another, and lock file content */
2391         while (1) {
2392                 struct btrfs_ordered_extent *ordered;
2393                 lock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2394                 ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2395                 if (!ordered &&
2396                     !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2397                                    EXTENT_DELALLOC, 0, NULL))
2398                         break;
2399                 unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2400                 if (ordered)
2401                         btrfs_put_ordered_extent(ordered);
2402                 btrfs_wait_ordered_range(src, off, len);
2403         }
2404
2405         /* clone data */
2406         key.objectid = btrfs_ino(src);
2407         key.type = BTRFS_EXTENT_DATA_KEY;
2408         key.offset = 0;
2409
2410         while (1) {
2411                 /*
2412                  * note the key will change type as we walk through the
2413                  * tree.
2414                  */
2415                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2416                 if (ret < 0)
2417                         goto out;
2418
2419                 nritems = btrfs_header_nritems(path->nodes[0]);
2420                 if (path->slots[0] >= nritems) {
2421                         ret = btrfs_next_leaf(root, path);
2422                         if (ret < 0)
2423                                 goto out;
2424                         if (ret > 0)
2425                                 break;
2426                         nritems = btrfs_header_nritems(path->nodes[0]);
2427                 }
2428                 leaf = path->nodes[0];
2429                 slot = path->slots[0];
2430
2431                 btrfs_item_key_to_cpu(leaf, &key, slot);
2432                 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2433                     key.objectid != btrfs_ino(src))
2434                         break;
2435
2436                 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2437                         struct btrfs_file_extent_item *extent;
2438                         int type;
2439                         u32 size;
2440                         struct btrfs_key new_key;
2441                         u64 disko = 0, diskl = 0;
2442                         u64 datao = 0, datal = 0;
2443                         u8 comp;
2444                         u64 endoff;
2445
2446                         size = btrfs_item_size_nr(leaf, slot);
2447                         read_extent_buffer(leaf, buf,
2448                                            btrfs_item_ptr_offset(leaf, slot),
2449                                            size);
2450
2451                         extent = btrfs_item_ptr(leaf, slot,
2452                                                 struct btrfs_file_extent_item);
2453                         comp = btrfs_file_extent_compression(leaf, extent);
2454                         type = btrfs_file_extent_type(leaf, extent);
2455                         if (type == BTRFS_FILE_EXTENT_REG ||
2456                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2457                                 disko = btrfs_file_extent_disk_bytenr(leaf,
2458                                                                       extent);
2459                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2460                                                                  extent);
2461                                 datao = btrfs_file_extent_offset(leaf, extent);
2462                                 datal = btrfs_file_extent_num_bytes(leaf,
2463                                                                     extent);
2464                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2465                                 /* take upper bound, may be compressed */
2466                                 datal = btrfs_file_extent_ram_bytes(leaf,
2467                                                                     extent);
2468                         }
2469                         btrfs_release_path(path);
2470
2471                         if (key.offset + datal <= off ||
2472                             key.offset >= off+len)
2473                                 goto next;
2474
2475                         memcpy(&new_key, &key, sizeof(new_key));
2476                         new_key.objectid = btrfs_ino(inode);
2477                         if (off <= key.offset)
2478                                 new_key.offset = key.offset + destoff - off;
2479                         else
2480                                 new_key.offset = destoff;
2481
2482                         /*
2483                          * 1 - adjusting old extent (we may have to split it)
2484                          * 1 - add new extent
2485                          * 1 - inode update
2486                          */
2487                         trans = btrfs_start_transaction(root, 3);
2488                         if (IS_ERR(trans)) {
2489                                 ret = PTR_ERR(trans);
2490                                 goto out;
2491                         }
2492
2493                         if (type == BTRFS_FILE_EXTENT_REG ||
2494                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2495                                 /*
2496                                  *    a  | --- range to clone ---|  b
2497                                  * | ------------- extent ------------- |
2498                                  */
2499
2500                                 /* substract range b */
2501                                 if (key.offset + datal > off + len)
2502                                         datal = off + len - key.offset;
2503
2504                                 /* substract range a */
2505                                 if (off > key.offset) {
2506                                         datao += off - key.offset;
2507                                         datal -= off - key.offset;
2508                                 }
2509
2510                                 ret = btrfs_drop_extents(trans, inode,
2511                                                          new_key.offset,
2512                                                          new_key.offset + datal,
2513                                                          &hint_byte, 1);
2514                                 if (ret) {
2515                                         btrfs_abort_transaction(trans, root,
2516                                                                 ret);
2517                                         btrfs_end_transaction(trans, root);
2518                                         goto out;
2519                                 }
2520
2521                                 ret = btrfs_insert_empty_item(trans, root, path,
2522                                                               &new_key, size);
2523                                 if (ret) {
2524                                         btrfs_abort_transaction(trans, root,
2525                                                                 ret);
2526                                         btrfs_end_transaction(trans, root);
2527                                         goto out;
2528                                 }
2529
2530                                 leaf = path->nodes[0];
2531                                 slot = path->slots[0];
2532                                 write_extent_buffer(leaf, buf,
2533                                             btrfs_item_ptr_offset(leaf, slot),
2534                                             size);
2535
2536                                 extent = btrfs_item_ptr(leaf, slot,
2537                                                 struct btrfs_file_extent_item);
2538
2539                                 /* disko == 0 means it's a hole */
2540                                 if (!disko)
2541                                         datao = 0;
2542
2543                                 btrfs_set_file_extent_offset(leaf, extent,
2544                                                              datao);
2545                                 btrfs_set_file_extent_num_bytes(leaf, extent,
2546                                                                 datal);
2547                                 if (disko) {
2548                                         inode_add_bytes(inode, datal);
2549                                         ret = btrfs_inc_extent_ref(trans, root,
2550                                                         disko, diskl, 0,
2551                                                         root->root_key.objectid,
2552                                                         btrfs_ino(inode),
2553                                                         new_key.offset - datao,
2554                                                         0);
2555                                         if (ret) {
2556                                                 btrfs_abort_transaction(trans,
2557                                                                         root,
2558                                                                         ret);
2559                                                 btrfs_end_transaction(trans,
2560                                                                       root);
2561                                                 goto out;
2562
2563                                         }
2564                                 }
2565                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2566                                 u64 skip = 0;
2567                                 u64 trim = 0;
2568                                 if (off > key.offset) {
2569                                         skip = off - key.offset;
2570                                         new_key.offset += skip;
2571                                 }
2572
2573                                 if (key.offset + datal > off+len)
2574                                         trim = key.offset + datal - (off+len);
2575
2576                                 if (comp && (skip || trim)) {
2577                                         ret = -EINVAL;
2578                                         btrfs_end_transaction(trans, root);
2579                                         goto out;
2580                                 }
2581                                 size -= skip + trim;
2582                                 datal -= skip + trim;
2583
2584                                 ret = btrfs_drop_extents(trans, inode,
2585                                                          new_key.offset,
2586                                                          new_key.offset + datal,
2587                                                          &hint_byte, 1);
2588                                 if (ret) {
2589                                         btrfs_abort_transaction(trans, root,
2590                                                                 ret);
2591                                         btrfs_end_transaction(trans, root);
2592                                         goto out;
2593                                 }
2594
2595                                 ret = btrfs_insert_empty_item(trans, root, path,
2596                                                               &new_key, size);
2597                                 if (ret) {
2598                                         btrfs_abort_transaction(trans, root,
2599                                                                 ret);
2600                                         btrfs_end_transaction(trans, root);
2601                                         goto out;
2602                                 }
2603
2604                                 if (skip) {
2605                                         u32 start =
2606                                           btrfs_file_extent_calc_inline_size(0);
2607                                         memmove(buf+start, buf+start+skip,
2608                                                 datal);
2609                                 }
2610
2611                                 leaf = path->nodes[0];
2612                                 slot = path->slots[0];
2613                                 write_extent_buffer(leaf, buf,
2614                                             btrfs_item_ptr_offset(leaf, slot),
2615                                             size);
2616                                 inode_add_bytes(inode, datal);
2617                         }
2618
2619                         btrfs_mark_buffer_dirty(leaf);
2620                         btrfs_release_path(path);
2621
2622                         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2623
2624                         /*
2625                          * we round up to the block size at eof when
2626                          * determining which extents to clone above,
2627                          * but shouldn't round up the file size
2628                          */
2629                         endoff = new_key.offset + datal;
2630                         if (endoff > destoff+olen)
2631                                 endoff = destoff+olen;
2632                         if (endoff > inode->i_size)
2633                                 btrfs_i_size_write(inode, endoff);
2634
2635                         ret = btrfs_update_inode(trans, root, inode);
2636                         if (ret) {
2637                                 btrfs_abort_transaction(trans, root, ret);
2638                                 btrfs_end_transaction(trans, root);
2639                                 goto out;
2640                         }
2641                         ret = btrfs_end_transaction(trans, root);
2642                 }
2643 next:
2644                 btrfs_release_path(path);
2645                 key.offset++;
2646         }
2647         ret = 0;
2648 out:
2649         btrfs_release_path(path);
2650         unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2651 out_unlock:
2652         mutex_unlock(&src->i_mutex);
2653         mutex_unlock(&inode->i_mutex);
2654         vfree(buf);
2655         btrfs_free_path(path);
2656 out_fput:
2657         fput(src_file);
2658 out_drop_write:
2659         mnt_drop_write_file(file);
2660         return ret;
2661 }
2662
2663 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2664 {
2665         struct btrfs_ioctl_clone_range_args args;
2666
2667         if (copy_from_user(&args, argp, sizeof(args)))
2668                 return -EFAULT;
2669         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2670                                  args.src_length, args.dest_offset);
2671 }
2672
2673 /*
2674  * there are many ways the trans_start and trans_end ioctls can lead
2675  * to deadlocks.  They should only be used by applications that
2676  * basically own the machine, and have a very in depth understanding
2677  * of all the possible deadlocks and enospc problems.
2678  */
2679 static long btrfs_ioctl_trans_start(struct file *file)
2680 {
2681         struct inode *inode = fdentry(file)->d_inode;
2682         struct btrfs_root *root = BTRFS_I(inode)->root;
2683         struct btrfs_trans_handle *trans;
2684         int ret;
2685
2686         ret = -EPERM;
2687         if (!capable(CAP_SYS_ADMIN))
2688                 goto out;
2689
2690         ret = -EINPROGRESS;
2691         if (file->private_data)
2692                 goto out;
2693
2694         ret = -EROFS;
2695         if (btrfs_root_readonly(root))
2696                 goto out;
2697
2698         ret = mnt_want_write_file(file);
2699         if (ret)
2700                 goto out;
2701
2702         atomic_inc(&root->fs_info->open_ioctl_trans);
2703
2704         ret = -ENOMEM;
2705         trans = btrfs_start_ioctl_transaction(root);
2706         if (IS_ERR(trans))
2707                 goto out_drop;
2708
2709         file->private_data = trans;
2710         return 0;
2711
2712 out_drop:
2713         atomic_dec(&root->fs_info->open_ioctl_trans);
2714         mnt_drop_write_file(file);
2715 out:
2716         return ret;
2717 }
2718
2719 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2720 {
2721         struct inode *inode = fdentry(file)->d_inode;
2722         struct btrfs_root *root = BTRFS_I(inode)->root;
2723         struct btrfs_root *new_root;
2724         struct btrfs_dir_item *di;
2725         struct btrfs_trans_handle *trans;
2726         struct btrfs_path *path;
2727         struct btrfs_key location;
2728         struct btrfs_disk_key disk_key;
2729         struct btrfs_super_block *disk_super;
2730         u64 features;
2731         u64 objectid = 0;
2732         u64 dir_id;
2733
2734         if (!capable(CAP_SYS_ADMIN))
2735                 return -EPERM;
2736
2737         if (copy_from_user(&objectid, argp, sizeof(objectid)))
2738                 return -EFAULT;
2739
2740         if (!objectid)
2741                 objectid = root->root_key.objectid;
2742
2743         location.objectid = objectid;
2744         location.type = BTRFS_ROOT_ITEM_KEY;
2745         location.offset = (u64)-1;
2746
2747         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2748         if (IS_ERR(new_root))
2749                 return PTR_ERR(new_root);
2750
2751         if (btrfs_root_refs(&new_root->root_item) == 0)
2752                 return -ENOENT;
2753
2754         path = btrfs_alloc_path();
2755         if (!path)
2756                 return -ENOMEM;
2757         path->leave_spinning = 1;
2758
2759         trans = btrfs_start_transaction(root, 1);
2760         if (IS_ERR(trans)) {
2761                 btrfs_free_path(path);
2762                 return PTR_ERR(trans);
2763         }
2764
2765         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2766         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2767                                    dir_id, "default", 7, 1);
2768         if (IS_ERR_OR_NULL(di)) {
2769                 btrfs_free_path(path);
2770                 btrfs_end_transaction(trans, root);
2771                 printk(KERN_ERR "Umm, you don't have the default dir item, "
2772                        "this isn't going to work\n");
2773                 return -ENOENT;
2774         }
2775
2776         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2777         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2778         btrfs_mark_buffer_dirty(path->nodes[0]);
2779         btrfs_free_path(path);
2780
2781         disk_super = root->fs_info->super_copy;
2782         features = btrfs_super_incompat_flags(disk_super);
2783         if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2784                 features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2785                 btrfs_set_super_incompat_flags(disk_super, features);
2786         }
2787         btrfs_end_transaction(trans, root);
2788
2789         return 0;
2790 }
2791
2792 static void get_block_group_info(struct list_head *groups_list,
2793                                  struct btrfs_ioctl_space_info *space)
2794 {
2795         struct btrfs_block_group_cache *block_group;
2796
2797         space->total_bytes = 0;
2798         space->used_bytes = 0;
2799         space->flags = 0;
2800         list_for_each_entry(block_group, groups_list, list) {
2801                 space->flags = block_group->flags;
2802                 space->total_bytes += block_group->key.offset;
2803                 space->used_bytes +=
2804                         btrfs_block_group_used(&block_group->item);
2805         }
2806 }
2807
2808 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
2809 {
2810         struct btrfs_ioctl_space_args space_args;
2811         struct btrfs_ioctl_space_info space;
2812         struct btrfs_ioctl_space_info *dest;
2813         struct btrfs_ioctl_space_info *dest_orig;
2814         struct btrfs_ioctl_space_info __user *user_dest;
2815         struct btrfs_space_info *info;
2816         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2817                        BTRFS_BLOCK_GROUP_SYSTEM,
2818                        BTRFS_BLOCK_GROUP_METADATA,
2819                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
2820         int num_types = 4;
2821         int alloc_size;
2822         int ret = 0;
2823         u64 slot_count = 0;
2824         int i, c;
2825
2826         if (copy_from_user(&space_args,
2827                            (struct btrfs_ioctl_space_args __user *)arg,
2828                            sizeof(space_args)))
2829                 return -EFAULT;
2830
2831         for (i = 0; i < num_types; i++) {
2832                 struct btrfs_space_info *tmp;
2833
2834                 info = NULL;
2835                 rcu_read_lock();
2836                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2837                                         list) {
2838                         if (tmp->flags == types[i]) {
2839                                 info = tmp;
2840                                 break;
2841                         }
2842                 }
2843                 rcu_read_unlock();
2844
2845                 if (!info)
2846                         continue;
2847
2848                 down_read(&info->groups_sem);
2849                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2850                         if (!list_empty(&info->block_groups[c]))
2851                                 slot_count++;
2852                 }
2853                 up_read(&info->groups_sem);
2854         }
2855
2856         /* space_slots == 0 means they are asking for a count */
2857         if (space_args.space_slots == 0) {
2858                 space_args.total_spaces = slot_count;
2859                 goto out;
2860         }
2861
2862         slot_count = min_t(u64, space_args.space_slots, slot_count);
2863
2864         alloc_size = sizeof(*dest) * slot_count;
2865
2866         /* we generally have at most 6 or so space infos, one for each raid
2867          * level.  So, a whole page should be more than enough for everyone
2868          */
2869         if (alloc_size > PAGE_CACHE_SIZE)
2870                 return -ENOMEM;
2871
2872         space_args.total_spaces = 0;
2873         dest = kmalloc(alloc_size, GFP_NOFS);
2874         if (!dest)
2875                 return -ENOMEM;
2876         dest_orig = dest;
2877
2878         /* now we have a buffer to copy into */
2879         for (i = 0; i < num_types; i++) {
2880                 struct btrfs_space_info *tmp;
2881
2882                 if (!slot_count)
2883                         break;
2884
2885                 info = NULL;
2886                 rcu_read_lock();
2887                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2888                                         list) {
2889                         if (tmp->flags == types[i]) {
2890                                 info = tmp;
2891                                 break;
2892                         }
2893                 }
2894                 rcu_read_unlock();
2895
2896                 if (!info)
2897                         continue;
2898                 down_read(&info->groups_sem);
2899                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2900                         if (!list_empty(&info->block_groups[c])) {
2901                                 get_block_group_info(&info->block_groups[c],
2902                                                      &space);
2903                                 memcpy(dest, &space, sizeof(space));
2904                                 dest++;
2905                                 space_args.total_spaces++;
2906                                 slot_count--;
2907                         }
2908                         if (!slot_count)
2909                                 break;
2910                 }
2911                 up_read(&info->groups_sem);
2912         }
2913
2914         user_dest = (struct btrfs_ioctl_space_info *)
2915                 (arg + sizeof(struct btrfs_ioctl_space_args));
2916
2917         if (copy_to_user(user_dest, dest_orig, alloc_size))
2918                 ret = -EFAULT;
2919
2920         kfree(dest_orig);
2921 out:
2922         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2923                 ret = -EFAULT;
2924
2925         return ret;
2926 }
2927
2928 /*
2929  * there are many ways the trans_start and trans_end ioctls can lead
2930  * to deadlocks.  They should only be used by applications that
2931  * basically own the machine, and have a very in depth understanding
2932  * of all the possible deadlocks and enospc problems.
2933  */
2934 long btrfs_ioctl_trans_end(struct file *file)
2935 {
2936         struct inode *inode = fdentry(file)->d_inode;
2937         struct btrfs_root *root = BTRFS_I(inode)->root;
2938         struct btrfs_trans_handle *trans;
2939
2940         trans = file->private_data;
2941         if (!trans)
2942                 return -EINVAL;
2943         file->private_data = NULL;
2944
2945         btrfs_end_transaction(trans, root);
2946
2947         atomic_dec(&root->fs_info->open_ioctl_trans);
2948
2949         mnt_drop_write_file(file);
2950         return 0;
2951 }
2952
2953 static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2954 {
2955         struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2956         struct btrfs_trans_handle *trans;
2957         u64 transid;
2958         int ret;
2959
2960         trans = btrfs_start_transaction(root, 0);
2961         if (IS_ERR(trans))
2962                 return PTR_ERR(trans);
2963         transid = trans->transid;
2964         ret = btrfs_commit_transaction_async(trans, root, 0);
2965         if (ret) {
2966                 btrfs_end_transaction(trans, root);
2967                 return ret;
2968         }
2969
2970         if (argp)
2971                 if (copy_to_user(argp, &transid, sizeof(transid)))
2972                         return -EFAULT;
2973         return 0;
2974 }
2975
2976 static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
2977 {
2978         struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2979         u64 transid;
2980
2981         if (argp) {
2982                 if (copy_from_user(&transid, argp, sizeof(transid)))
2983                         return -EFAULT;
2984         } else {
2985                 transid = 0;  /* current trans */
2986         }
2987         return btrfs_wait_for_commit(root, transid);
2988 }
2989
2990 static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
2991 {
2992         int ret;
2993         struct btrfs_ioctl_scrub_args *sa;
2994
2995         if (!capable(CAP_SYS_ADMIN))
2996                 return -EPERM;
2997
2998         sa = memdup_user(arg, sizeof(*sa));
2999         if (IS_ERR(sa))
3000                 return PTR_ERR(sa);
3001
3002         ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
3003                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
3004
3005         if (copy_to_user(arg, sa, sizeof(*sa)))
3006                 ret = -EFAULT;
3007
3008         kfree(sa);
3009         return ret;
3010 }
3011
3012 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3013 {
3014         if (!capable(CAP_SYS_ADMIN))
3015                 return -EPERM;
3016
3017         return btrfs_scrub_cancel(root);
3018 }
3019
3020 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3021                                        void __user *arg)
3022 {
3023         struct btrfs_ioctl_scrub_args *sa;
3024         int ret;
3025
3026         if (!capable(CAP_SYS_ADMIN))
3027                 return -EPERM;
3028
3029         sa = memdup_user(arg, sizeof(*sa));
3030         if (IS_ERR(sa))
3031                 return PTR_ERR(sa);
3032
3033         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3034
3035         if (copy_to_user(arg, sa, sizeof(*sa)))
3036                 ret = -EFAULT;
3037
3038         kfree(sa);
3039         return ret;
3040 }
3041
3042 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3043 {
3044         int ret = 0;
3045         int i;
3046         u64 rel_ptr;
3047         int size;
3048         struct btrfs_ioctl_ino_path_args *ipa = NULL;
3049         struct inode_fs_paths *ipath = NULL;
3050         struct btrfs_path *path;
3051
3052         if (!capable(CAP_SYS_ADMIN))
3053                 return -EPERM;
3054
3055         path = btrfs_alloc_path();
3056         if (!path) {
3057                 ret = -ENOMEM;
3058                 goto out;
3059         }
3060
3061         ipa = memdup_user(arg, sizeof(*ipa));
3062         if (IS_ERR(ipa)) {
3063                 ret = PTR_ERR(ipa);
3064                 ipa = NULL;
3065                 goto out;
3066         }
3067
3068         size = min_t(u32, ipa->size, 4096);
3069         ipath = init_ipath(size, root, path);
3070         if (IS_ERR(ipath)) {
3071                 ret = PTR_ERR(ipath);
3072                 ipath = NULL;
3073                 goto out;
3074         }
3075
3076         ret = paths_from_inode(ipa->inum, ipath);
3077         if (ret < 0)
3078                 goto out;
3079
3080         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3081                 rel_ptr = ipath->fspath->val[i] -
3082                           (u64)(unsigned long)ipath->fspath->val;
3083                 ipath->fspath->val[i] = rel_ptr;
3084         }
3085
3086         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3087                            (void *)(unsigned long)ipath->fspath, size);
3088         if (ret) {
3089                 ret = -EFAULT;
3090                 goto out;
3091         }
3092
3093 out:
3094         btrfs_free_path(path);
3095         free_ipath(ipath);
3096         kfree(ipa);
3097
3098         return ret;
3099 }
3100
3101 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3102 {
3103         struct btrfs_data_container *inodes = ctx;
3104         const size_t c = 3 * sizeof(u64);
3105
3106         if (inodes->bytes_left >= c) {
3107                 inodes->bytes_left -= c;
3108                 inodes->val[inodes->elem_cnt] = inum;
3109                 inodes->val[inodes->elem_cnt + 1] = offset;
3110                 inodes->val[inodes->elem_cnt + 2] = root;
3111                 inodes->elem_cnt += 3;
3112         } else {
3113                 inodes->bytes_missing += c - inodes->bytes_left;
3114                 inodes->bytes_left = 0;
3115                 inodes->elem_missed += 3;
3116         }
3117
3118         return 0;
3119 }
3120
3121 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3122                                         void __user *arg)
3123 {
3124         int ret = 0;
3125         int size;
3126         u64 extent_item_pos;
3127         struct btrfs_ioctl_logical_ino_args *loi;
3128         struct btrfs_data_container *inodes = NULL;
3129         struct btrfs_path *path = NULL;
3130         struct btrfs_key key;
3131
3132         if (!capable(CAP_SYS_ADMIN))
3133                 return -EPERM;
3134
3135         loi = memdup_user(arg, sizeof(*loi));
3136         if (IS_ERR(loi)) {
3137                 ret = PTR_ERR(loi);
3138                 loi = NULL;
3139                 goto out;
3140         }
3141
3142         path = btrfs_alloc_path();
3143         if (!path) {
3144                 ret = -ENOMEM;
3145                 goto out;
3146         }
3147
3148         size = min_t(u32, loi->size, 4096);
3149         inodes = init_data_container(size);
3150         if (IS_ERR(inodes)) {
3151                 ret = PTR_ERR(inodes);
3152                 inodes = NULL;
3153                 goto out;
3154         }
3155
3156         ret = extent_from_logical(root->fs_info, loi->logical, path, &key);
3157         btrfs_release_path(path);
3158
3159         if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
3160                 ret = -ENOENT;
3161         if (ret < 0)
3162                 goto out;
3163
3164         extent_item_pos = loi->logical - key.objectid;
3165         ret = iterate_extent_inodes(root->fs_info, key.objectid,
3166                                         extent_item_pos, 0, build_ino_list,
3167                                         inodes);
3168
3169         if (ret < 0)
3170                 goto out;
3171
3172         ret = copy_to_user((void *)(unsigned long)loi->inodes,
3173                            (void *)(unsigned long)inodes, size);
3174         if (ret)
3175                 ret = -EFAULT;
3176
3177 out:
3178         btrfs_free_path(path);
3179         kfree(inodes);
3180         kfree(loi);
3181
3182         return ret;
3183 }
3184
3185 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3186                                struct btrfs_ioctl_balance_args *bargs)
3187 {
3188         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3189
3190         bargs->flags = bctl->flags;
3191
3192         if (atomic_read(&fs_info->balance_running))
3193                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3194         if (atomic_read(&fs_info->balance_pause_req))
3195                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3196         if (atomic_read(&fs_info->balance_cancel_req))
3197                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3198
3199         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3200         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3201         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3202
3203         if (lock) {
3204                 spin_lock(&fs_info->balance_lock);
3205                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3206                 spin_unlock(&fs_info->balance_lock);
3207         } else {
3208                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3209         }
3210 }
3211
3212 static long btrfs_ioctl_balance(struct btrfs_root *root, void __user *arg)
3213 {
3214         struct btrfs_fs_info *fs_info = root->fs_info;
3215         struct btrfs_ioctl_balance_args *bargs;
3216         struct btrfs_balance_control *bctl;
3217         int ret;
3218
3219         if (!capable(CAP_SYS_ADMIN))
3220                 return -EPERM;
3221
3222         if (fs_info->sb->s_flags & MS_RDONLY)
3223                 return -EROFS;
3224
3225         mutex_lock(&fs_info->volume_mutex);
3226         mutex_lock(&fs_info->balance_mutex);
3227
3228         if (arg) {
3229                 bargs = memdup_user(arg, sizeof(*bargs));
3230                 if (IS_ERR(bargs)) {
3231                         ret = PTR_ERR(bargs);
3232                         goto out;
3233                 }
3234
3235                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3236                         if (!fs_info->balance_ctl) {
3237                                 ret = -ENOTCONN;
3238                                 goto out_bargs;
3239                         }
3240
3241                         bctl = fs_info->balance_ctl;
3242                         spin_lock(&fs_info->balance_lock);
3243                         bctl->flags |= BTRFS_BALANCE_RESUME;
3244                         spin_unlock(&fs_info->balance_lock);
3245
3246                         goto do_balance;
3247                 }
3248         } else {
3249                 bargs = NULL;
3250         }
3251
3252         if (fs_info->balance_ctl) {
3253                 ret = -EINPROGRESS;
3254                 goto out_bargs;
3255         }
3256
3257         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3258         if (!bctl) {
3259                 ret = -ENOMEM;
3260                 goto out_bargs;
3261         }
3262
3263         bctl->fs_info = fs_info;
3264         if (arg) {
3265                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3266                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3267                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3268
3269                 bctl->flags = bargs->flags;
3270         } else {
3271                 /* balance everything - no filters */
3272                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3273         }
3274
3275 do_balance:
3276         ret = btrfs_balance(bctl, bargs);
3277         /*
3278          * bctl is freed in __cancel_balance or in free_fs_info if
3279          * restriper was paused all the way until unmount
3280          */
3281         if (arg) {
3282                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3283                         ret = -EFAULT;
3284         }
3285
3286 out_bargs:
3287         kfree(bargs);
3288 out:
3289         mutex_unlock(&fs_info->balance_mutex);
3290         mutex_unlock(&fs_info->volume_mutex);
3291         return ret;
3292 }
3293
3294 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3295 {
3296         if (!capable(CAP_SYS_ADMIN))
3297                 return -EPERM;
3298
3299         switch (cmd) {
3300         case BTRFS_BALANCE_CTL_PAUSE:
3301                 return btrfs_pause_balance(root->fs_info);
3302         case BTRFS_BALANCE_CTL_CANCEL:
3303                 return btrfs_cancel_balance(root->fs_info);
3304         }
3305
3306         return -EINVAL;
3307 }
3308
3309 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3310                                          void __user *arg)
3311 {
3312         struct btrfs_fs_info *fs_info = root->fs_info;
3313         struct btrfs_ioctl_balance_args *bargs;
3314         int ret = 0;
3315
3316         if (!capable(CAP_SYS_ADMIN))
3317                 return -EPERM;
3318
3319         mutex_lock(&fs_info->balance_mutex);
3320         if (!fs_info->balance_ctl) {
3321                 ret = -ENOTCONN;
3322                 goto out;
3323         }
3324
3325         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3326         if (!bargs) {
3327                 ret = -ENOMEM;
3328                 goto out;
3329         }
3330
3331         update_ioctl_balance_args(fs_info, 1, bargs);
3332
3333         if (copy_to_user(arg, bargs, sizeof(*bargs)))
3334                 ret = -EFAULT;
3335
3336         kfree(bargs);
3337 out:
3338         mutex_unlock(&fs_info->balance_mutex);
3339         return ret;
3340 }
3341
3342 long btrfs_ioctl(struct file *file, unsigned int
3343                 cmd, unsigned long arg)
3344 {
3345         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3346         void __user *argp = (void __user *)arg;
3347
3348         switch (cmd) {
3349         case FS_IOC_GETFLAGS:
3350                 return btrfs_ioctl_getflags(file, argp);
3351         case FS_IOC_SETFLAGS:
3352                 return btrfs_ioctl_setflags(file, argp);
3353         case FS_IOC_GETVERSION:
3354                 return btrfs_ioctl_getversion(file, argp);
3355         case FITRIM:
3356                 return btrfs_ioctl_fitrim(file, argp);
3357         case BTRFS_IOC_SNAP_CREATE:
3358                 return btrfs_ioctl_snap_create(file, argp, 0);
3359         case BTRFS_IOC_SNAP_CREATE_V2:
3360                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
3361         case BTRFS_IOC_SUBVOL_CREATE:
3362                 return btrfs_ioctl_snap_create(file, argp, 1);
3363         case BTRFS_IOC_SNAP_DESTROY:
3364                 return btrfs_ioctl_snap_destroy(file, argp);
3365         case BTRFS_IOC_SUBVOL_GETFLAGS:
3366                 return btrfs_ioctl_subvol_getflags(file, argp);
3367         case BTRFS_IOC_SUBVOL_SETFLAGS:
3368                 return btrfs_ioctl_subvol_setflags(file, argp);
3369         case BTRFS_IOC_DEFAULT_SUBVOL:
3370                 return btrfs_ioctl_default_subvol(file, argp);
3371         case BTRFS_IOC_DEFRAG:
3372                 return btrfs_ioctl_defrag(file, NULL);
3373         case BTRFS_IOC_DEFRAG_RANGE:
3374                 return btrfs_ioctl_defrag(file, argp);
3375         case BTRFS_IOC_RESIZE:
3376                 return btrfs_ioctl_resize(root, argp);
3377         case BTRFS_IOC_ADD_DEV:
3378                 return btrfs_ioctl_add_dev(root, argp);
3379         case BTRFS_IOC_RM_DEV:
3380                 return btrfs_ioctl_rm_dev(root, argp);
3381         case BTRFS_IOC_FS_INFO:
3382                 return btrfs_ioctl_fs_info(root, argp);
3383         case BTRFS_IOC_DEV_INFO:
3384                 return btrfs_ioctl_dev_info(root, argp);
3385         case BTRFS_IOC_BALANCE:
3386                 return btrfs_ioctl_balance(root, NULL);
3387         case BTRFS_IOC_CLONE:
3388                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
3389         case BTRFS_IOC_CLONE_RANGE:
3390                 return btrfs_ioctl_clone_range(file, argp);
3391         case BTRFS_IOC_TRANS_START:
3392                 return btrfs_ioctl_trans_start(file);
3393         case BTRFS_IOC_TRANS_END:
3394                 return btrfs_ioctl_trans_end(file);
3395         case BTRFS_IOC_TREE_SEARCH:
3396                 return btrfs_ioctl_tree_search(file, argp);
3397         case BTRFS_IOC_INO_LOOKUP:
3398                 return btrfs_ioctl_ino_lookup(file, argp);
3399         case BTRFS_IOC_INO_PATHS:
3400                 return btrfs_ioctl_ino_to_path(root, argp);
3401         case BTRFS_IOC_LOGICAL_INO:
3402                 return btrfs_ioctl_logical_to_ino(root, argp);
3403         case BTRFS_IOC_SPACE_INFO:
3404                 return btrfs_ioctl_space_info(root, argp);
3405         case BTRFS_IOC_SYNC:
3406                 btrfs_sync_fs(file->f_dentry->d_sb, 1);
3407                 return 0;
3408         case BTRFS_IOC_START_SYNC:
3409                 return btrfs_ioctl_start_sync(file, argp);
3410         case BTRFS_IOC_WAIT_SYNC:
3411                 return btrfs_ioctl_wait_sync(file, argp);
3412         case BTRFS_IOC_SCRUB:
3413                 return btrfs_ioctl_scrub(root, argp);
3414         case BTRFS_IOC_SCRUB_CANCEL:
3415                 return btrfs_ioctl_scrub_cancel(root, argp);
3416         case BTRFS_IOC_SCRUB_PROGRESS:
3417                 return btrfs_ioctl_scrub_progress(root, argp);
3418         case BTRFS_IOC_BALANCE_V2:
3419                 return btrfs_ioctl_balance(root, argp);
3420         case BTRFS_IOC_BALANCE_CTL:
3421                 return btrfs_ioctl_balance_ctl(root, arg);
3422         case BTRFS_IOC_BALANCE_PROGRESS:
3423                 return btrfs_ioctl_balance_progress(root, argp);
3424         }
3425
3426         return -ENOTTY;
3427 }