fs/btrfs/ioctl.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/bio.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/file.h>
  23 #include <linux/fs.h>
  24 #include <linux/fsnotify.h>
  25 #include <linux/pagemap.h>
  26 #include <linux/highmem.h>
  27 #include <linux/time.h>
  28 #include <linux/init.h>
  29 #include <linux/string.h>
  30 #include <linux/backing-dev.h>
  31 #include <linux/mount.h>
  32 #include <linux/mpage.h>
  33 #include <linux/namei.h>
  34 #include <linux/swap.h>
  35 #include <linux/writeback.h>
  36 #include <linux/statfs.h>
  37 #include <linux/compat.h>
  38 #include <linux/bit_spinlock.h>
  39 #include <linux/security.h>
  40 #include <linux/xattr.h>
  41 #include <linux/vmalloc.h>
  42 #include <linux/slab.h>
  43 #include <linux/blkdev.h>
  44 #include <linux/uuid.h>
  45 #include <linux/btrfs.h>
  46 #include "compat.h"
  47 #include "ctree.h"
  48 #include "disk-io.h"
  49 #include "transaction.h"
  50 #include "btrfs_inode.h"
  51 #include "print-tree.h"
  52 #include "volumes.h"
  53 #include "locking.h"
  54 #include "inode-map.h"
  55 #include "backref.h"
  56 #include "rcu-string.h"
  57 #include "send.h"
  58 #include "dev-replace.h"
  59
  60 /* Mask out flags that are inappropriate for the given type of inode. */
  61 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
  62 {
  63         if (S_ISDIR(mode))
  64                 return flags;
  65         else if (S_ISREG(mode))
  66                 return flags & ~FS_DIRSYNC_FL;
  67         else
  68                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
  69 }
  70
  71 /*
  72  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
  73  */
  74 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
  75 {
  76         unsigned int iflags = 0;
  77
  78         if (flags & BTRFS_INODE_SYNC)
  79                 iflags |= FS_SYNC_FL;
  80         if (flags & BTRFS_INODE_IMMUTABLE)
  81                 iflags |= FS_IMMUTABLE_FL;
  82         if (flags & BTRFS_INODE_APPEND)
  83                 iflags |= FS_APPEND_FL;
  84         if (flags & BTRFS_INODE_NODUMP)
  85                 iflags |= FS_NODUMP_FL;
  86         if (flags & BTRFS_INODE_NOATIME)
  87                 iflags |= FS_NOATIME_FL;
  88         if (flags & BTRFS_INODE_DIRSYNC)
  89                 iflags |= FS_DIRSYNC_FL;
  90         if (flags & BTRFS_INODE_NODATACOW)
  91                 iflags |= FS_NOCOW_FL;
  92
  93         if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
  94                 iflags |= FS_COMPR_FL;
  95         else if (flags & BTRFS_INODE_NOCOMPRESS)
  96                 iflags |= FS_NOCOMP_FL;
  97
  98         return iflags;
  99 }
 100
 101 /*
 102  * Update inode->i_flags based on the btrfs internal flags.
 103  */
 104 void btrfs_update_iflags(struct inode *inode)
 105 {
 106         struct btrfs_inode *ip = BTRFS_I(inode);
 107
 108         inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
 109
 110         if (ip->flags & BTRFS_INODE_SYNC)
 111                 inode->i_flags |= S_SYNC;
 112         if (ip->flags & BTRFS_INODE_IMMUTABLE)
 113                 inode->i_flags |= S_IMMUTABLE;
 114         if (ip->flags & BTRFS_INODE_APPEND)
 115                 inode->i_flags |= S_APPEND;
 116         if (ip->flags & BTRFS_INODE_NOATIME)
 117                 inode->i_flags |= S_NOATIME;
 118         if (ip->flags & BTRFS_INODE_DIRSYNC)
 119                 inode->i_flags |= S_DIRSYNC;
 120 }
 121
 122 /*
 123  * Inherit flags from the parent inode.
 124  *
 125  * Currently only the compression flags and the cow flags are inherited.
 126  */
 127 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 128 {
 129         unsigned int flags;
 130
 131         if (!dir)
 132                 return;
 133
 134         flags = BTRFS_I(dir)->flags;
 135
 136         if (flags & BTRFS_INODE_NOCOMPRESS) {
 137                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 138                 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 139         } else if (flags & BTRFS_INODE_COMPRESS) {
 140                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 141                 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 142         }
 143
 144         if (flags & BTRFS_INODE_NODATACOW) {
 145                 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 146                 if (S_ISREG(inode->i_mode))
 147                         BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
 148         }
 149
 150         btrfs_update_iflags(inode);
 151 }
 152
 153 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 154 {
 155         struct btrfs_inode *ip = BTRFS_I(file_inode(file));
 156         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 157
 158         if (copy_to_user(arg, &flags, sizeof(flags)))
 159                 return -EFAULT;
 160         return 0;
 161 }
 162
 163 static int check_flags(unsigned int flags)
 164 {
 165         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 166                       FS_NOATIME_FL | FS_NODUMP_FL | \
 167                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 168                       FS_NOCOMP_FL | FS_COMPR_FL |
 169                       FS_NOCOW_FL))
 170                 return -EOPNOTSUPP;
 171
 172         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 173                 return -EINVAL;
 174
 175         return 0;
 176 }
 177
 178 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 179 {
 180         struct inode *inode = file_inode(file);
 181         struct btrfs_inode *ip = BTRFS_I(inode);
 182         struct btrfs_root *root = ip->root;
 183         struct btrfs_trans_handle *trans;
 184         unsigned int flags, oldflags;
 185         int ret;
 186         u64 ip_oldflags;
 187         unsigned int i_oldflags;
 188         umode_t mode;
 189
 190         if (btrfs_root_readonly(root))
 191                 return -EROFS;
 192
 193         if (copy_from_user(&flags, arg, sizeof(flags)))
 194                 return -EFAULT;
 195
 196         ret = check_flags(flags);
 197         if (ret)
 198                 return ret;
 199
 200         if (!inode_owner_or_capable(inode))
 201                 return -EACCES;
 202
 203         ret = mnt_want_write_file(file);
 204         if (ret)
 205                 return ret;
 206
 207         mutex_lock(&inode->i_mutex);
 208
 209         ip_oldflags = ip->flags;
 210         i_oldflags = inode->i_flags;
 211         mode = inode->i_mode;
 212
 213         flags = btrfs_mask_flags(inode->i_mode, flags);
 214         oldflags = btrfs_flags_to_ioctl(ip->flags);
 215         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 216                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 217                         ret = -EPERM;
 218                         goto out_unlock;
 219                 }
 220         }
 221
 222         if (flags & FS_SYNC_FL)
 223                 ip->flags |= BTRFS_INODE_SYNC;
 224         else
 225                 ip->flags &= ~BTRFS_INODE_SYNC;
 226         if (flags & FS_IMMUTABLE_FL)
 227                 ip->flags |= BTRFS_INODE_IMMUTABLE;
 228         else
 229                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 230         if (flags & FS_APPEND_FL)
 231                 ip->flags |= BTRFS_INODE_APPEND;
 232         else
 233                 ip->flags &= ~BTRFS_INODE_APPEND;
 234         if (flags & FS_NODUMP_FL)
 235                 ip->flags |= BTRFS_INODE_NODUMP;
 236         else
 237                 ip->flags &= ~BTRFS_INODE_NODUMP;
 238         if (flags & FS_NOATIME_FL)
 239                 ip->flags |= BTRFS_INODE_NOATIME;
 240         else
 241                 ip->flags &= ~BTRFS_INODE_NOATIME;
 242         if (flags & FS_DIRSYNC_FL)
 243                 ip->flags |= BTRFS_INODE_DIRSYNC;
 244         else
 245                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
 246         if (flags & FS_NOCOW_FL) {
 247                 if (S_ISREG(mode)) {
 248                         /*
 249                          * It's safe to turn csums off here, no extents exist.
 250                          * Otherwise we want the flag to reflect the real COW
 251                          * status of the file and will not set it.
 252                          */
 253                         if (inode->i_size == 0)
 254                                 ip->flags |= BTRFS_INODE_NODATACOW
 255                                            | BTRFS_INODE_NODATASUM;
 256                 } else {
 257                         ip->flags |= BTRFS_INODE_NODATACOW;
 258                 }
 259         } else {
 260                 /*
 261                  * Revert back under same assuptions as above
 262                  */
 263                 if (S_ISREG(mode)) {
 264                         if (inode->i_size == 0)
 265                                 ip->flags &= ~(BTRFS_INODE_NODATACOW
 266                                              | BTRFS_INODE_NODATASUM);
 267                 } else {
 268                         ip->flags &= ~BTRFS_INODE_NODATACOW;
 269                 }
 270         }
 271
 272         /*
 273          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 274          * flag may be changed automatically if compression code won't make
 275          * things smaller.
 276          */
 277         if (flags & FS_NOCOMP_FL) {
 278                 ip->flags &= ~BTRFS_INODE_COMPRESS;
 279                 ip->flags |= BTRFS_INODE_NOCOMPRESS;
 280         } else if (flags & FS_COMPR_FL) {
 281                 ip->flags |= BTRFS_INODE_COMPRESS;
 282                 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 283         } else {
 284                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 285         }
 286
 287         trans = btrfs_start_transaction(root, 1);
 288         if (IS_ERR(trans)) {
 289                 ret = PTR_ERR(trans);
 290                 goto out_drop;
 291         }
 292
 293         btrfs_update_iflags(inode);
 294         inode_inc_iversion(inode);
 295         inode->i_ctime = CURRENT_TIME;
 296         ret = btrfs_update_inode(trans, root, inode);
 297
 298         btrfs_end_transaction(trans, root);
 299  out_drop:
 300         if (ret) {
 301                 ip->flags = ip_oldflags;
 302                 inode->i_flags = i_oldflags;
 303         }
 304
 305  out_unlock:
 306         mutex_unlock(&inode->i_mutex);
 307         mnt_drop_write_file(file);
 308         return ret;
 309 }
 310
 311 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 312 {
 313         struct inode *inode = file_inode(file);
 314
 315         return put_user(inode->i_generation, arg);
 316 }
 317
 318 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 319 {
 320         struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
 321         struct btrfs_device *device;
 322         struct request_queue *q;
 323         struct fstrim_range range;
 324         u64 minlen = ULLONG_MAX;
 325         u64 num_devices = 0;
 326         u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 327         int ret;
 328
 329         if (!capable(CAP_SYS_ADMIN))
 330                 return -EPERM;
 331
 332         rcu_read_lock();
 333         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 334                                 dev_list) {
 335                 if (!device->bdev)
 336                         continue;
 337                 q = bdev_get_queue(device->bdev);
 338                 if (blk_queue_discard(q)) {
 339                         num_devices++;
 340                         minlen = min((u64)q->limits.discard_granularity,
 341                                      minlen);
 342                 }
 343         }
 344         rcu_read_unlock();
 345
 346         if (!num_devices)
 347                 return -EOPNOTSUPP;
 348         if (copy_from_user(&range, arg, sizeof(range)))
 349                 return -EFAULT;
 350         if (range.start > total_bytes ||
 351             range.len < fs_info->sb->s_blocksize)
 352                 return -EINVAL;
 353
 354         range.len = min(range.len, total_bytes - range.start);
 355         range.minlen = max(range.minlen, minlen);
 356         ret = btrfs_trim_fs(fs_info->tree_root, &range);
 357         if (ret < 0)
 358                 return ret;
 359
 360         if (copy_to_user(arg, &range, sizeof(range)))
 361                 return -EFAULT;
 362
 363         return 0;
 364 }
 365
 366 static noinline int create_subvol(struct inode *dir,
 367                                   struct dentry *dentry,
 368                                   char *name, int namelen,
 369                                   u64 *async_transid,
 370                                   struct btrfs_qgroup_inherit *inherit)
 371 {
 372         struct btrfs_trans_handle *trans;
 373         struct btrfs_key key;
 374         struct btrfs_root_item root_item;
 375         struct btrfs_inode_item *inode_item;
 376         struct extent_buffer *leaf;
 377         struct btrfs_root *root = BTRFS_I(dir)->root;
 378         struct btrfs_root *new_root;
 379         struct btrfs_block_rsv block_rsv;
 380         struct timespec cur_time = CURRENT_TIME;
 381         int ret;
 382         int err;
 383         u64 objectid;
 384         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 385         u64 index = 0;
 386         u64 qgroup_reserved;
 387         uuid_le new_uuid;
 388
 389         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 390         if (ret)
 391                 return ret;
 392
 393         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 394         /*
 395          * The same as the snapshot creation, please see the comment
 396          * of create_snapshot().
 397          */
 398         ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
 399                                                7, &qgroup_reserved);
 400         if (ret)
 401                 return ret;
 402
 403         trans = btrfs_start_transaction(root, 0);
 404         if (IS_ERR(trans)) {
 405                 ret = PTR_ERR(trans);
 406                 goto out;
 407         }
 408         trans->block_rsv = &block_rsv;
 409         trans->bytes_reserved = block_rsv.size;
 410
 411         ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
 412         if (ret)
 413                 goto fail;
 414
 415         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
 416                                       0, objectid, NULL, 0, 0, 0);
 417         if (IS_ERR(leaf)) {
 418                 ret = PTR_ERR(leaf);
 419                 goto fail;
 420         }
 421
 422         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 423         btrfs_set_header_bytenr(leaf, leaf->start);
 424         btrfs_set_header_generation(leaf, trans->transid);
 425         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 426         btrfs_set_header_owner(leaf, objectid);
 427
 428         write_extent_buffer(leaf, root->fs_info->fsid,
 429                             (unsigned long)btrfs_header_fsid(leaf),
 430                             BTRFS_FSID_SIZE);
 431         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 432                             (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
 433                             BTRFS_UUID_SIZE);
 434         btrfs_mark_buffer_dirty(leaf);
 435
 436         memset(&root_item, 0, sizeof(root_item));
 437
 438         inode_item = &root_item.inode;
 439         inode_item->generation = cpu_to_le64(1);
 440         inode_item->size = cpu_to_le64(3);
 441         inode_item->nlink = cpu_to_le32(1);
 442         inode_item->nbytes = cpu_to_le64(root->leafsize);
 443         inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 444
 445         root_item.flags = 0;
 446         root_item.byte_limit = 0;
 447         inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
 448
 449         btrfs_set_root_bytenr(&root_item, leaf->start);
 450         btrfs_set_root_generation(&root_item, trans->transid);
 451         btrfs_set_root_level(&root_item, 0);
 452         btrfs_set_root_refs(&root_item, 1);
 453         btrfs_set_root_used(&root_item, leaf->len);
 454         btrfs_set_root_last_snapshot(&root_item, 0);
 455
 456         btrfs_set_root_generation_v2(&root_item,
 457                         btrfs_root_generation(&root_item));
 458         uuid_le_gen(&new_uuid);
 459         memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
 460         root_item.otime.sec = cpu_to_le64(cur_time.tv_sec);
 461         root_item.otime.nsec = cpu_to_le32(cur_time.tv_nsec);
 462         root_item.ctime = root_item.otime;
 463         btrfs_set_root_ctransid(&root_item, trans->transid);
 464         btrfs_set_root_otransid(&root_item, trans->transid);
 465
 466         btrfs_tree_unlock(leaf);
 467         free_extent_buffer(leaf);
 468         leaf = NULL;
 469
 470         btrfs_set_root_dirid(&root_item, new_dirid);
 471
 472         key.objectid = objectid;
 473         key.offset = 0;
 474         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 475         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 476                                 &root_item);
 477         if (ret)
 478                 goto fail;
 479
 480         key.offset = (u64)-1;
 481         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 482         if (IS_ERR(new_root)) {
 483                 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 484                 ret = PTR_ERR(new_root);
 485                 goto fail;
 486         }
 487
 488         btrfs_record_root_in_trans(trans, new_root);
 489
 490         ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
 491         if (ret) {
 492                 /* We potentially lose an unused inode item here */
 493                 btrfs_abort_transaction(trans, root, ret);
 494                 goto fail;
 495         }
 496
 497         /*
 498          * insert the directory item
 499          */
 500         ret = btrfs_set_inode_index(dir, &index);
 501         if (ret) {
 502                 btrfs_abort_transaction(trans, root, ret);
 503                 goto fail;
 504         }
 505
 506         ret = btrfs_insert_dir_item(trans, root,
 507                                     name, namelen, dir, &key,
 508                                     BTRFS_FT_DIR, index);
 509         if (ret) {
 510                 btrfs_abort_transaction(trans, root, ret);
 511                 goto fail;
 512         }
 513
 514         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 515         ret = btrfs_update_inode(trans, root, dir);
 516         BUG_ON(ret);
 517
 518         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 519                                  objectid, root->root_key.objectid,
 520                                  btrfs_ino(dir), index, name, namelen);
 521
 522         BUG_ON(ret);
 523
 524 fail:
 525         trans->block_rsv = NULL;
 526         trans->bytes_reserved = 0;
 527         if (async_transid) {
 528                 *async_transid = trans->transid;
 529                 err = btrfs_commit_transaction_async(trans, root, 1);
 530         } else {
 531                 err = btrfs_commit_transaction(trans, root);
 532         }
 533         if (err && !ret)
 534                 ret = err;
 535
 536         if (!ret)
 537                 d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 538 out:
 539         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 540         return ret;
 541 }
 542
 543 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 544                            struct dentry *dentry, char *name, int namelen,
 545                            u64 *async_transid, bool readonly,
 546                            struct btrfs_qgroup_inherit *inherit)
 547 {
 548         struct inode *inode;
 549         struct btrfs_pending_snapshot *pending_snapshot;
 550         struct btrfs_trans_handle *trans;
 551         int ret;
 552
 553         if (!root->ref_cows)
 554                 return -EINVAL;
 555
 556         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 557         if (!pending_snapshot)
 558                 return -ENOMEM;
 559
 560         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 561                              BTRFS_BLOCK_RSV_TEMP);
 562         /*
 563          * 1 - parent dir inode
 564          * 2 - dir entries
 565          * 1 - root item
 566          * 2 - root ref/backref
 567          * 1 - root of snapshot
 568          */
 569         ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 570                                         &pending_snapshot->block_rsv, 7,
 571                                         &pending_snapshot->qgroup_reserved);
 572         if (ret)
 573                 goto out;
 574
 575         pending_snapshot->dentry = dentry;
 576         pending_snapshot->root = root;
 577         pending_snapshot->readonly = readonly;
 578         pending_snapshot->dir = dir;
 579         pending_snapshot->inherit = inherit;
 580
 581         trans = btrfs_start_transaction(root, 0);
 582         if (IS_ERR(trans)) {
 583                 ret = PTR_ERR(trans);
 584                 goto fail;
 585         }
 586
 587         spin_lock(&root->fs_info->trans_lock);
 588         list_add(&pending_snapshot->list,
 589                  &trans->transaction->pending_snapshots);
 590         spin_unlock(&root->fs_info->trans_lock);
 591         if (async_transid) {
 592                 *async_transid = trans->transid;
 593                 ret = btrfs_commit_transaction_async(trans,
 594                                      root->fs_info->extent_root, 1);
 595         } else {
 596                 ret = btrfs_commit_transaction(trans,
 597                                                root->fs_info->extent_root);
 598         }
 599         if (ret) {
 600                 /* cleanup_transaction has freed this for us */
 601                 if (trans->aborted)
 602                         pending_snapshot = NULL;
 603                 goto fail;
 604         }
 605
 606         ret = pending_snapshot->error;
 607         if (ret)
 608                 goto fail;
 609
 610         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 611         if (ret)
 612                 goto fail;
 613
 614         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 615         if (IS_ERR(inode)) {
 616                 ret = PTR_ERR(inode);
 617                 goto fail;
 618         }
 619         BUG_ON(!inode);
 620         d_instantiate(dentry, inode);
 621         ret = 0;
 622 fail:
 623         btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
 624                                          &pending_snapshot->block_rsv,
 625                                          pending_snapshot->qgroup_reserved);
 626 out:
 627         kfree(pending_snapshot);
 628         return ret;
 629 }
 630
 631 /*  copy of check_sticky in fs/namei.c()
 632 * It's inline, so penalty for filesystems that don't use sticky bit is
 633 * minimal.
 634 */
 635 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 636 {
 637         kuid_t fsuid = current_fsuid();
 638
 639         if (!(dir->i_mode & S_ISVTX))
 640                 return 0;
 641         if (uid_eq(inode->i_uid, fsuid))
 642                 return 0;
 643         if (uid_eq(dir->i_uid, fsuid))
 644                 return 0;
 645         return !capable(CAP_FOWNER);
 646 }
 647
 648 /*  copy of may_delete in fs/namei.c()
 649  *      Check whether we can remove a link victim from directory dir, check
 650  *  whether the type of victim is right.
 651  *  1. We can't do it if dir is read-only (done in permission())
 652  *  2. We should have write and exec permissions on dir
 653  *  3. We can't remove anything from append-only dir
 654  *  4. We can't do anything with immutable dir (done in permission())
 655  *  5. If the sticky bit on dir is set we should either
 656  *      a. be owner of dir, or
 657  *      b. be owner of victim, or
 658  *      c. have CAP_FOWNER capability
 659  *  6. If the victim is append-only or immutable we can't do antyhing with
 660  *     links pointing to it.
 661  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 662  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 663  *  9. We can't remove a root or mountpoint.
 664  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 665  *     nfs_async_unlink().
 666  */
 667
 668 static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
 669 {
 670         int error;
 671
 672         if (!victim->d_inode)
 673                 return -ENOENT;
 674
 675         BUG_ON(victim->d_parent->d_inode != dir);
 676         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 677
 678         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 679         if (error)
 680                 return error;
 681         if (IS_APPEND(dir))
 682                 return -EPERM;
 683         if (btrfs_check_sticky(dir, victim->d_inode)||
 684                 IS_APPEND(victim->d_inode)||
 685             IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 686                 return -EPERM;
 687         if (isdir) {
 688                 if (!S_ISDIR(victim->d_inode->i_mode))
 689                         return -ENOTDIR;
 690                 if (IS_ROOT(victim))
 691                         return -EBUSY;
 692         } else if (S_ISDIR(victim->d_inode->i_mode))
 693                 return -EISDIR;
 694         if (IS_DEADDIR(dir))
 695                 return -ENOENT;
 696         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 697                 return -EBUSY;
 698         return 0;
 699 }
 700
 701 /* copy of may_create in fs/namei.c() */
 702 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 703 {
 704         if (child->d_inode)
 705                 return -EEXIST;
 706         if (IS_DEADDIR(dir))
 707                 return -ENOENT;
 708         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 709 }
 710
 711 /*
 712  * Create a new subvolume below @parent.  This is largely modeled after
 713  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 714  * inside this filesystem so it's quite a bit simpler.
 715  */
 716 static noinline int btrfs_mksubvol(struct path *parent,
 717                                    char *name, int namelen,
 718                                    struct btrfs_root *snap_src,
 719                                    u64 *async_transid, bool readonly,
 720                                    struct btrfs_qgroup_inherit *inherit)
 721 {
 722         struct inode *dir  = parent->dentry->d_inode;
 723         struct dentry *dentry;
 724         int error;
 725
 726         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
 727
 728         dentry = lookup_one_len(name, parent->dentry, namelen);
 729         error = PTR_ERR(dentry);
 730         if (IS_ERR(dentry))
 731                 goto out_unlock;
 732
 733         error = -EEXIST;
 734         if (dentry->d_inode)
 735                 goto out_dput;
 736
 737         error = btrfs_may_create(dir, dentry);
 738         if (error)
 739                 goto out_dput;
 740
 741         /*
 742          * even if this name doesn't exist, we may get hash collisions.
 743          * check for them now when we can safely fail
 744          */
 745         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 746                                                dir->i_ino, name,
 747                                                namelen);
 748         if (error)
 749                 goto out_dput;
 750
 751         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 752
 753         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 754                 goto out_up_read;
 755
 756         if (snap_src) {
 757                 error = create_snapshot(snap_src, dir, dentry, name, namelen,
 758                                         async_transid, readonly, inherit);
 759         } else {
 760                 error = create_subvol(dir, dentry, name, namelen,
 761                                       async_transid, inherit);
 762         }
 763         if (!error)
 764                 fsnotify_mkdir(dir, dentry);
 765 out_up_read:
 766         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 767 out_dput:
 768         dput(dentry);
 769 out_unlock:
 770         mutex_unlock(&dir->i_mutex);
 771         return error;
 772 }
 773
 774 /*
 775  * When we're defragging a range, we don't want to kick it off again
 776  * if it is really just waiting for delalloc to send it down.
 777  * If we find a nice big extent or delalloc range for the bytes in the
 778  * file you want to defrag, we return 0 to let you know to skip this
 779  * part of the file
 780  */
 781 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
 782 {
 783         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 784         struct extent_map *em = NULL;
 785         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 786         u64 end;
 787
 788         read_lock(&em_tree->lock);
 789         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 790         read_unlock(&em_tree->lock);
 791
 792         if (em) {
 793                 end = extent_map_end(em);
 794                 free_extent_map(em);
 795                 if (end - offset > thresh)
 796                         return 0;
 797         }
 798         /* if we already have a nice delalloc here, just stop */
 799         thresh /= 2;
 800         end = count_range_bits(io_tree, &offset, offset + thresh,
 801                                thresh, EXTENT_DELALLOC, 1);
 802         if (end >= thresh)
 803                 return 0;
 804         return 1;
 805 }
 806
 807 /*
 808  * helper function to walk through a file and find extents
 809  * newer than a specific transid, and smaller than thresh.
 810  *
 811  * This is used by the defragging code to find new and small
 812  * extents
 813  */
 814 static int find_new_extents(struct btrfs_root *root,
 815                             struct inode *inode, u64 newer_than,
 816                             u64 *off, int thresh)
 817 {
 818         struct btrfs_path *path;
 819         struct btrfs_key min_key;
 820         struct btrfs_key max_key;
 821         struct extent_buffer *leaf;
 822         struct btrfs_file_extent_item *extent;
 823         int type;
 824         int ret;
 825         u64 ino = btrfs_ino(inode);
 826
 827         path = btrfs_alloc_path();
 828         if (!path)
 829                 return -ENOMEM;
 830
 831         min_key.objectid = ino;
 832         min_key.type = BTRFS_EXTENT_DATA_KEY;
 833         min_key.offset = *off;
 834
 835         max_key.objectid = ino;
 836         max_key.type = (u8)-1;
 837         max_key.offset = (u64)-1;
 838
 839         path->keep_locks = 1;
 840
 841         while(1) {
 842                 ret = btrfs_search_forward(root, &min_key, &max_key,
 843                                            path, newer_than);
 844                 if (ret != 0)
 845                         goto none;
 846                 if (min_key.objectid != ino)
 847                         goto none;
 848                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 849                         goto none;
 850
 851                 leaf = path->nodes[0];
 852                 extent = btrfs_item_ptr(leaf, path->slots[0],
 853                                         struct btrfs_file_extent_item);
 854
 855                 type = btrfs_file_extent_type(leaf, extent);
 856                 if (type == BTRFS_FILE_EXTENT_REG &&
 857                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 858                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 859                         *off = min_key.offset;
 860                         btrfs_free_path(path);
 861                         return 0;
 862                 }
 863
 864                 if (min_key.offset == (u64)-1)
 865                         goto none;
 866
 867                 min_key.offset++;
 868                 btrfs_release_path(path);
 869         }
 870 none:
 871         btrfs_free_path(path);
 872         return -ENOENT;
 873 }
 874
 875 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 876 {
 877         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 878         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 879         struct extent_map *em;
 880         u64 len = PAGE_CACHE_SIZE;
 881
 882         /*
 883          * hopefully we have this extent in the tree already, try without
 884          * the full extent lock
 885          */
 886         read_lock(&em_tree->lock);
 887         em = lookup_extent_mapping(em_tree, start, len);
 888         read_unlock(&em_tree->lock);
 889
 890         if (!em) {
 891                 /* get the big lock and read metadata off disk */
 892                 lock_extent(io_tree, start, start + len - 1);
 893                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 894                 unlock_extent(io_tree, start, start + len - 1);
 895
 896                 if (IS_ERR(em))
 897                         return NULL;
 898         }
 899
 900         return em;
 901 }
 902
 903 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
 904 {
 905         struct extent_map *next;
 906         bool ret = true;
 907
 908         /* this is the last extent */
 909         if (em->start + em->len >= i_size_read(inode))
 910                 return false;
 911
 912         next = defrag_lookup_extent(inode, em->start + em->len);
 913         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
 914                 ret = false;
 915
 916         free_extent_map(next);
 917         return ret;
 918 }
 919
 920 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
 921                                u64 *last_len, u64 *skip, u64 *defrag_end,
 922                                int compress)
 923 {
 924         struct extent_map *em;
 925         int ret = 1;
 926         bool next_mergeable = true;
 927
 928         /*
 929          * make sure that once we start defragging an extent, we keep on
 930          * defragging it
 931          */
 932         if (start < *defrag_end)
 933                 return 1;
 934
 935         *skip = 0;
 936
 937         em = defrag_lookup_extent(inode, start);
 938         if (!em)
 939                 return 0;
 940
 941         /* this will cover holes, and inline extents */
 942         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
 943                 ret = 0;
 944                 goto out;
 945         }
 946
 947         next_mergeable = defrag_check_next_extent(inode, em);
 948
 949         /*
 950          * we hit a real extent, if it is big or the next extent is not a
 951          * real extent, don't bother defragging it
 952          */
 953         if (!compress && (*last_len == 0 || *last_len >= thresh) &&
 954             (em->len >= thresh || !next_mergeable))
 955                 ret = 0;
 956 out:
 957         /*
 958          * last_len ends up being a counter of how many bytes we've defragged.
 959          * every time we choose not to defrag an extent, we reset *last_len
 960          * so that the next tiny extent will force a defrag.
 961          *
 962          * The end result of this is that tiny extents before a single big
 963          * extent will force at least part of that big extent to be defragged.
 964          */
 965         if (ret) {
 966                 *defrag_end = extent_map_end(em);
 967         } else {
 968                 *last_len = 0;
 969                 *skip = extent_map_end(em);
 970                 *defrag_end = 0;
 971         }
 972
 973         free_extent_map(em);
 974         return ret;
 975 }
 976
 977 /*
 978  * it doesn't do much good to defrag one or two pages
 979  * at a time.  This pulls in a nice chunk of pages
 980  * to COW and defrag.
 981  *
 982  * It also makes sure the delalloc code has enough
 983  * dirty data to avoid making new small extents as part
 984  * of the defrag
 985  *
 986  * It's a good idea to start RA on this range
 987  * before calling this.
 988  */
 989 static int cluster_pages_for_defrag(struct inode *inode,
 990                                     struct page **pages,
 991                                     unsigned long start_index,
 992                                     int num_pages)
 993 {
 994         unsigned long file_end;
 995         u64 isize = i_size_read(inode);
 996         u64 page_start;
 997         u64 page_end;
 998         u64 page_cnt;
 999         int ret;
1000         int i;
1001         int i_done;
1002         struct btrfs_ordered_extent *ordered;
1003         struct extent_state *cached_state = NULL;
1004         struct extent_io_tree *tree;
1005         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1006
1007         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1008         if (!isize || start_index > file_end)
1009                 return 0;
1010
1011         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1012
1013         ret = btrfs_delalloc_reserve_space(inode,
1014                                            page_cnt << PAGE_CACHE_SHIFT);
1015         if (ret)
1016                 return ret;
1017         i_done = 0;
1018         tree = &BTRFS_I(inode)->io_tree;
1019
1020         /* step one, lock all the pages */
1021         for (i = 0; i < page_cnt; i++) {
1022                 struct page *page;
1023 again:
1024                 page = find_or_create_page(inode->i_mapping,
1025                                            start_index + i, mask);
1026                 if (!page)
1027                         break;
1028
1029                 page_start = page_offset(page);
1030                 page_end = page_start + PAGE_CACHE_SIZE - 1;
1031                 while (1) {
1032                         lock_extent(tree, page_start, page_end);
1033                         ordered = btrfs_lookup_ordered_extent(inode,
1034                                                               page_start);
1035                         unlock_extent(tree, page_start, page_end);
1036                         if (!ordered)
1037                                 break;
1038
1039                         unlock_page(page);
1040                         btrfs_start_ordered_extent(inode, ordered, 1);
1041                         btrfs_put_ordered_extent(ordered);
1042                         lock_page(page);
1043                         /*
1044                          * we unlocked the page above, so we need check if
1045                          * it was released or not.
1046                          */
1047                         if (page->mapping != inode->i_mapping) {
1048                                 unlock_page(page);
1049                                 page_cache_release(page);
1050                                 goto again;
1051                         }
1052                 }
1053
1054                 if (!PageUptodate(page)) {
1055                         btrfs_readpage(NULL, page);
1056                         lock_page(page);
1057                         if (!PageUptodate(page)) {
1058                                 unlock_page(page);
1059                                 page_cache_release(page);
1060                                 ret = -EIO;
1061                                 break;
1062                         }
1063                 }
1064
1065                 if (page->mapping != inode->i_mapping) {
1066                         unlock_page(page);
1067                         page_cache_release(page);
1068                         goto again;
1069                 }
1070
1071                 pages[i] = page;
1072                 i_done++;
1073         }
1074         if (!i_done || ret)
1075                 goto out;
1076
1077         if (!(inode->i_sb->s_flags & MS_ACTIVE))
1078                 goto out;
1079
1080         /*
1081          * so now we have a nice long stream of locked
1082          * and up to date pages, lets wait on them
1083          */
1084         for (i = 0; i < i_done; i++)
1085                 wait_on_page_writeback(pages[i]);
1086
1087         page_start = page_offset(pages[0]);
1088         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1089
1090         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1091                          page_start, page_end - 1, 0, &cached_state);
1092         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1093                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1094                           EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1095                           &cached_state, GFP_NOFS);
1096
1097         if (i_done != page_cnt) {
1098                 spin_lock(&BTRFS_I(inode)->lock);
1099                 BTRFS_I(inode)->outstanding_extents++;
1100                 spin_unlock(&BTRFS_I(inode)->lock);
1101                 btrfs_delalloc_release_space(inode,
1102                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1103         }
1104
1105
1106         set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1107                           &cached_state, GFP_NOFS);
1108
1109         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1110                              page_start, page_end - 1, &cached_state,
1111                              GFP_NOFS);
1112
1113         for (i = 0; i < i_done; i++) {
1114                 clear_page_dirty_for_io(pages[i]);
1115                 ClearPageChecked(pages[i]);
1116                 set_page_extent_mapped(pages[i]);
1117                 set_page_dirty(pages[i]);
1118                 unlock_page(pages[i]);
1119                 page_cache_release(pages[i]);
1120         }
1121         return i_done;
1122 out:
1123         for (i = 0; i < i_done; i++) {
1124                 unlock_page(pages[i]);
1125                 page_cache_release(pages[i]);
1126         }
1127         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1128         return ret;
1129
1130 }
1131
1132 int btrfs_defrag_file(struct inode *inode, struct file *file,
1133                       struct btrfs_ioctl_defrag_range_args *range,
1134                       u64 newer_than, unsigned long max_to_defrag)
1135 {
1136         struct btrfs_root *root = BTRFS_I(inode)->root;
1137         struct file_ra_state *ra = NULL;
1138         unsigned long last_index;
1139         u64 isize = i_size_read(inode);
1140         u64 last_len = 0;
1141         u64 skip = 0;
1142         u64 defrag_end = 0;
1143         u64 newer_off = range->start;
1144         unsigned long i;
1145         unsigned long ra_index = 0;
1146         int ret;
1147         int defrag_count = 0;
1148         int compress_type = BTRFS_COMPRESS_ZLIB;
1149         int extent_thresh = range->extent_thresh;
1150         int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1151         int cluster = max_cluster;
1152         u64 new_align = ~((u64)128 * 1024 - 1);
1153         struct page **pages = NULL;
1154
1155         if (extent_thresh == 0)
1156                 extent_thresh = 256 * 1024;
1157
1158         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1159                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1160                         return -EINVAL;
1161                 if (range->compress_type)
1162                         compress_type = range->compress_type;
1163         }
1164
1165         if (isize == 0)
1166                 return 0;
1167
1168         /*
1169          * if we were not given a file, allocate a readahead
1170          * context
1171          */
1172         if (!file) {
1173                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1174                 if (!ra)
1175                         return -ENOMEM;
1176                 file_ra_state_init(ra, inode->i_mapping);
1177         } else {
1178                 ra = &file->f_ra;
1179         }
1180
1181         pages = kmalloc(sizeof(struct page *) * max_cluster,
1182                         GFP_NOFS);
1183         if (!pages) {
1184                 ret = -ENOMEM;
1185                 goto out_ra;
1186         }
1187
1188         /* find the last page to defrag */
1189         if (range->start + range->len > range->start) {
1190                 last_index = min_t(u64, isize - 1,
1191                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1192         } else {
1193                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1194         }
1195
1196         if (newer_than) {
1197                 ret = find_new_extents(root, inode, newer_than,
1198                                        &newer_off, 64 * 1024);
1199                 if (!ret) {
1200                         range->start = newer_off;
1201                         /*
1202                          * we always align our defrag to help keep
1203                          * the extents in the file evenly spaced
1204                          */
1205                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1206                 } else
1207                         goto out_ra;
1208         } else {
1209                 i = range->start >> PAGE_CACHE_SHIFT;
1210         }
1211         if (!max_to_defrag)
1212                 max_to_defrag = last_index + 1;
1213
1214         /*
1215          * make writeback starts from i, so the defrag range can be
1216          * written sequentially.
1217          */
1218         if (i < inode->i_mapping->writeback_index)
1219                 inode->i_mapping->writeback_index = i;
1220
1221         while (i <= last_index && defrag_count < max_to_defrag &&
1222                (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1223                 PAGE_CACHE_SHIFT)) {
1224                 /*
1225                  * make sure we stop running if someone unmounts
1226                  * the FS
1227                  */
1228                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1229                         break;
1230
1231                 if (btrfs_defrag_cancelled(root->fs_info)) {
1232                         printk(KERN_DEBUG "btrfs: defrag_file cancelled\n");
1233                         ret = -EAGAIN;
1234                         break;
1235                 }
1236
1237                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1238                                          extent_thresh, &last_len, &skip,
1239                                          &defrag_end, range->flags &
1240                                          BTRFS_DEFRAG_RANGE_COMPRESS)) {
1241                         unsigned long next;
1242                         /*
1243                          * the should_defrag function tells us how much to skip
1244                          * bump our counter by the suggested amount
1245                          */
1246                         next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1247                         i = max(i + 1, next);
1248                         continue;
1249                 }
1250
1251                 if (!newer_than) {
1252                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1253                                    PAGE_CACHE_SHIFT) - i;
1254                         cluster = min(cluster, max_cluster);
1255                 } else {
1256                         cluster = max_cluster;
1257                 }
1258
1259                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1260                         BTRFS_I(inode)->force_compress = compress_type;
1261
1262                 if (i + cluster > ra_index) {
1263                         ra_index = max(i, ra_index);
1264                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1265                                        cluster);
1266                         ra_index += max_cluster;
1267                 }
1268
1269                 mutex_lock(&inode->i_mutex);
1270                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1271                 if (ret < 0) {
1272                         mutex_unlock(&inode->i_mutex);
1273                         goto out_ra;
1274                 }
1275
1276                 defrag_count += ret;
1277                 balance_dirty_pages_ratelimited(inode->i_mapping);
1278                 mutex_unlock(&inode->i_mutex);
1279
1280                 if (newer_than) {
1281                         if (newer_off == (u64)-1)
1282                                 break;
1283
1284                         if (ret > 0)
1285                                 i += ret;
1286
1287                         newer_off = max(newer_off + 1,
1288                                         (u64)i << PAGE_CACHE_SHIFT);
1289
1290                         ret = find_new_extents(root, inode,
1291                                                newer_than, &newer_off,
1292                                                64 * 1024);
1293                         if (!ret) {
1294                                 range->start = newer_off;
1295                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1296                         } else {
1297                                 break;
1298                         }
1299                 } else {
1300                         if (ret > 0) {
1301                                 i += ret;
1302                                 last_len += ret << PAGE_CACHE_SHIFT;
1303                         } else {
1304                                 i++;
1305                                 last_len = 0;
1306                         }
1307                 }
1308         }
1309
1310         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1311                 filemap_flush(inode->i_mapping);
1312
1313         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1314                 /* the filemap_flush will queue IO into the worker threads, but
1315                  * we have to make sure the IO is actually started and that
1316                  * ordered extents get created before we return
1317                  */
1318                 atomic_inc(&root->fs_info->async_submit_draining);
1319                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1320                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1321                         wait_event(root->fs_info->async_submit_wait,
1322                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1323                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1324                 }
1325                 atomic_dec(&root->fs_info->async_submit_draining);
1326
1327                 mutex_lock(&inode->i_mutex);
1328                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1329                 mutex_unlock(&inode->i_mutex);
1330         }
1331
1332         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1333                 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1334         }
1335
1336         ret = defrag_count;
1337
1338 out_ra:
1339         if (!file)
1340                 kfree(ra);
1341         kfree(pages);
1342         return ret;
1343 }
1344
1345 static noinline int btrfs_ioctl_resize(struct file *file,
1346                                         void __user *arg)
1347 {
1348         u64 new_size;
1349         u64 old_size;
1350         u64 devid = 1;
1351         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1352         struct btrfs_ioctl_vol_args *vol_args;
1353         struct btrfs_trans_handle *trans;
1354         struct btrfs_device *device = NULL;
1355         char *sizestr;
1356         char *devstr = NULL;
1357         int ret = 0;
1358         int mod = 0;
1359
1360         if (!capable(CAP_SYS_ADMIN))
1361                 return -EPERM;
1362
1363         ret = mnt_want_write_file(file);
1364         if (ret)
1365                 return ret;
1366
1367         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1368                         1)) {
1369                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
1370                 mnt_drop_write_file(file);
1371                 return -EINVAL;
1372         }
1373
1374         mutex_lock(&root->fs_info->volume_mutex);
1375         vol_args = memdup_user(arg, sizeof(*vol_args));
1376         if (IS_ERR(vol_args)) {
1377                 ret = PTR_ERR(vol_args);
1378                 goto out;
1379         }
1380
1381         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1382
1383         sizestr = vol_args->name;
1384         devstr = strchr(sizestr, ':');
1385         if (devstr) {
1386                 char *end;
1387                 sizestr = devstr + 1;
1388                 *devstr = '\0';
1389                 devstr = vol_args->name;
1390                 devid = simple_strtoull(devstr, &end, 10);
1391                 if (!devid) {
1392                         ret = -EINVAL;
1393                         goto out_free;
1394                 }
1395                 printk(KERN_INFO "btrfs: resizing devid %llu\n",
1396                        (unsigned long long)devid);
1397         }
1398
1399         device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1400         if (!device) {
1401                 printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1402                        (unsigned long long)devid);
1403                 ret = -ENODEV;
1404                 goto out_free;
1405         }
1406
1407         if (!device->writeable) {
1408                 printk(KERN_INFO "btrfs: resizer unable to apply on "
1409                        "readonly device %llu\n",
1410                        (unsigned long long)devid);
1411                 ret = -EPERM;
1412                 goto out_free;
1413         }
1414
1415         if (!strcmp(sizestr, "max"))
1416                 new_size = device->bdev->bd_inode->i_size;
1417         else {
1418                 if (sizestr[0] == '-') {
1419                         mod = -1;
1420                         sizestr++;
1421                 } else if (sizestr[0] == '+') {
1422                         mod = 1;
1423                         sizestr++;
1424                 }
1425                 new_size = memparse(sizestr, NULL);
1426                 if (new_size == 0) {
1427                         ret = -EINVAL;
1428                         goto out_free;
1429                 }
1430         }
1431
1432         if (device->is_tgtdev_for_dev_replace) {
1433                 ret = -EPERM;
1434                 goto out_free;
1435         }
1436
1437         old_size = device->total_bytes;
1438
1439         if (mod < 0) {
1440                 if (new_size > old_size) {
1441                         ret = -EINVAL;
1442                         goto out_free;
1443                 }
1444                 new_size = old_size - new_size;
1445         } else if (mod > 0) {
1446                 new_size = old_size + new_size;
1447         }
1448
1449         if (new_size < 256 * 1024 * 1024) {
1450                 ret = -EINVAL;
1451                 goto out_free;
1452         }
1453         if (new_size > device->bdev->bd_inode->i_size) {
1454                 ret = -EFBIG;
1455                 goto out_free;
1456         }
1457
1458         do_div(new_size, root->sectorsize);
1459         new_size *= root->sectorsize;
1460
1461         printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1462                       rcu_str_deref(device->name),
1463                       (unsigned long long)new_size);
1464
1465         if (new_size > old_size) {
1466                 trans = btrfs_start_transaction(root, 0);
1467                 if (IS_ERR(trans)) {
1468                         ret = PTR_ERR(trans);
1469                         goto out_free;
1470                 }
1471                 ret = btrfs_grow_device(trans, device, new_size);
1472                 btrfs_commit_transaction(trans, root);
1473         } else if (new_size < old_size) {
1474                 ret = btrfs_shrink_device(device, new_size);
1475         } /* equal, nothing need to do */
1476
1477 out_free:
1478         kfree(vol_args);
1479 out:
1480         mutex_unlock(&root->fs_info->volume_mutex);
1481         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1482         mnt_drop_write_file(file);
1483         return ret;
1484 }
1485
1486 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1487                                 char *name, unsigned long fd, int subvol,
1488                                 u64 *transid, bool readonly,
1489                                 struct btrfs_qgroup_inherit *inherit)
1490 {
1491         int namelen;
1492         int ret = 0;
1493
1494         ret = mnt_want_write_file(file);
1495         if (ret)
1496                 goto out;
1497
1498         namelen = strlen(name);
1499         if (strchr(name, '/')) {
1500                 ret = -EINVAL;
1501                 goto out_drop_write;
1502         }
1503
1504         if (name[0] == '.' &&
1505            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1506                 ret = -EEXIST;
1507                 goto out_drop_write;
1508         }
1509
1510         if (subvol) {
1511                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1512                                      NULL, transid, readonly, inherit);
1513         } else {
1514                 struct fd src = fdget(fd);
1515                 struct inode *src_inode;
1516                 if (!src.file) {
1517                         ret = -EINVAL;
1518                         goto out_drop_write;
1519                 }
1520
1521                 src_inode = file_inode(src.file);
1522                 if (src_inode->i_sb != file_inode(file)->i_sb) {
1523                         printk(KERN_INFO "btrfs: Snapshot src from "
1524                                "another FS\n");
1525                         ret = -EINVAL;
1526                 } else {
1527                         ret = btrfs_mksubvol(&file->f_path, name, namelen,
1528                                              BTRFS_I(src_inode)->root,
1529                                              transid, readonly, inherit);
1530                 }
1531                 fdput(src);
1532         }
1533 out_drop_write:
1534         mnt_drop_write_file(file);
1535 out:
1536         return ret;
1537 }
1538
1539 static noinline int btrfs_ioctl_snap_create(struct file *file,
1540                                             void __user *arg, int subvol)
1541 {
1542         struct btrfs_ioctl_vol_args *vol_args;
1543         int ret;
1544
1545         vol_args = memdup_user(arg, sizeof(*vol_args));
1546         if (IS_ERR(vol_args))
1547                 return PTR_ERR(vol_args);
1548         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1549
1550         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1551                                               vol_args->fd, subvol,
1552                                               NULL, false, NULL);
1553
1554         kfree(vol_args);
1555         return ret;
1556 }
1557
1558 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1559                                                void __user *arg, int subvol)
1560 {
1561         struct btrfs_ioctl_vol_args_v2 *vol_args;
1562         int ret;
1563         u64 transid = 0;
1564         u64 *ptr = NULL;
1565         bool readonly = false;
1566         struct btrfs_qgroup_inherit *inherit = NULL;
1567
1568         vol_args = memdup_user(arg, sizeof(*vol_args));
1569         if (IS_ERR(vol_args))
1570                 return PTR_ERR(vol_args);
1571         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1572
1573         if (vol_args->flags &
1574             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1575               BTRFS_SUBVOL_QGROUP_INHERIT)) {
1576                 ret = -EOPNOTSUPP;
1577                 goto out;
1578         }
1579
1580         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1581                 ptr = &transid;
1582         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1583                 readonly = true;
1584         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1585                 if (vol_args->size > PAGE_CACHE_SIZE) {
1586                         ret = -EINVAL;
1587                         goto out;
1588                 }
1589                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1590                 if (IS_ERR(inherit)) {
1591                         ret = PTR_ERR(inherit);
1592                         goto out;
1593                 }
1594         }
1595
1596         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1597                                               vol_args->fd, subvol, ptr,
1598                                               readonly, inherit);
1599
1600         if (ret == 0 && ptr &&
1601             copy_to_user(arg +
1602                          offsetof(struct btrfs_ioctl_vol_args_v2,
1603                                   transid), ptr, sizeof(*ptr)))
1604                 ret = -EFAULT;
1605 out:
1606         kfree(vol_args);
1607         kfree(inherit);
1608         return ret;
1609 }
1610
1611 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1612                                                 void __user *arg)
1613 {
1614         struct inode *inode = file_inode(file);
1615         struct btrfs_root *root = BTRFS_I(inode)->root;
1616         int ret = 0;
1617         u64 flags = 0;
1618
1619         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1620                 return -EINVAL;
1621
1622         down_read(&root->fs_info->subvol_sem);
1623         if (btrfs_root_readonly(root))
1624                 flags |= BTRFS_SUBVOL_RDONLY;
1625         up_read(&root->fs_info->subvol_sem);
1626
1627         if (copy_to_user(arg, &flags, sizeof(flags)))
1628                 ret = -EFAULT;
1629
1630         return ret;
1631 }
1632
1633 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1634                                               void __user *arg)
1635 {
1636         struct inode *inode = file_inode(file);
1637         struct btrfs_root *root = BTRFS_I(inode)->root;
1638         struct btrfs_trans_handle *trans;
1639         u64 root_flags;
1640         u64 flags;
1641         int ret = 0;
1642
1643         ret = mnt_want_write_file(file);
1644         if (ret)
1645                 goto out;
1646
1647         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1648                 ret = -EINVAL;
1649                 goto out_drop_write;
1650         }
1651
1652         if (copy_from_user(&flags, arg, sizeof(flags))) {
1653                 ret = -EFAULT;
1654                 goto out_drop_write;
1655         }
1656
1657         if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1658                 ret = -EINVAL;
1659                 goto out_drop_write;
1660         }
1661
1662         if (flags & ~BTRFS_SUBVOL_RDONLY) {
1663                 ret = -EOPNOTSUPP;
1664                 goto out_drop_write;
1665         }
1666
1667         if (!inode_owner_or_capable(inode)) {
1668                 ret = -EACCES;
1669                 goto out_drop_write;
1670         }
1671
1672         down_write(&root->fs_info->subvol_sem);
1673
1674         /* nothing to do */
1675         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1676                 goto out_drop_sem;
1677
1678         root_flags = btrfs_root_flags(&root->root_item);
1679         if (flags & BTRFS_SUBVOL_RDONLY)
1680                 btrfs_set_root_flags(&root->root_item,
1681                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1682         else
1683                 btrfs_set_root_flags(&root->root_item,
1684                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1685
1686         trans = btrfs_start_transaction(root, 1);
1687         if (IS_ERR(trans)) {
1688                 ret = PTR_ERR(trans);
1689                 goto out_reset;
1690         }
1691
1692         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1693                                 &root->root_key, &root->root_item);
1694
1695         btrfs_commit_transaction(trans, root);
1696 out_reset:
1697         if (ret)
1698                 btrfs_set_root_flags(&root->root_item, root_flags);
1699 out_drop_sem:
1700         up_write(&root->fs_info->subvol_sem);
1701 out_drop_write:
1702         mnt_drop_write_file(file);
1703 out:
1704         return ret;
1705 }
1706
1707 /*
1708  * helper to check if the subvolume references other subvolumes
1709  */
1710 static noinline int may_destroy_subvol(struct btrfs_root *root)
1711 {
1712         struct btrfs_path *path;
1713         struct btrfs_key key;
1714         int ret;
1715
1716         path = btrfs_alloc_path();
1717         if (!path)
1718                 return -ENOMEM;
1719
1720         key.objectid = root->root_key.objectid;
1721         key.type = BTRFS_ROOT_REF_KEY;
1722         key.offset = (u64)-1;
1723
1724         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1725                                 &key, path, 0, 0);
1726         if (ret < 0)
1727                 goto out;
1728         BUG_ON(ret == 0);
1729
1730         ret = 0;
1731         if (path->slots[0] > 0) {
1732                 path->slots[0]--;
1733                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1734                 if (key.objectid == root->root_key.objectid &&
1735                     key.type == BTRFS_ROOT_REF_KEY)
1736                         ret = -ENOTEMPTY;
1737         }
1738 out:
1739         btrfs_free_path(path);
1740         return ret;
1741 }
1742
1743 static noinline int key_in_sk(struct btrfs_key *key,
1744                               struct btrfs_ioctl_search_key *sk)
1745 {
1746         struct btrfs_key test;
1747         int ret;
1748
1749         test.objectid = sk->min_objectid;
1750         test.type = sk->min_type;
1751         test.offset = sk->min_offset;
1752
1753         ret = btrfs_comp_cpu_keys(key, &test);
1754         if (ret < 0)
1755                 return 0;
1756
1757         test.objectid = sk->max_objectid;
1758         test.type = sk->max_type;
1759         test.offset = sk->max_offset;
1760
1761         ret = btrfs_comp_cpu_keys(key, &test);
1762         if (ret > 0)
1763                 return 0;
1764         return 1;
1765 }
1766
1767 static noinline int copy_to_sk(struct btrfs_root *root,
1768                                struct btrfs_path *path,
1769                                struct btrfs_key *key,
1770                                struct btrfs_ioctl_search_key *sk,
1771                                char *buf,
1772                                unsigned long *sk_offset,
1773                                int *num_found)
1774 {
1775         u64 found_transid;
1776         struct extent_buffer *leaf;
1777         struct btrfs_ioctl_search_header sh;
1778         unsigned long item_off;
1779         unsigned long item_len;
1780         int nritems;
1781         int i;
1782         int slot;
1783         int ret = 0;
1784
1785         leaf = path->nodes[0];
1786         slot = path->slots[0];
1787         nritems = btrfs_header_nritems(leaf);
1788
1789         if (btrfs_header_generation(leaf) > sk->max_transid) {
1790                 i = nritems;
1791                 goto advance_key;
1792         }
1793         found_transid = btrfs_header_generation(leaf);
1794
1795         for (i = slot; i < nritems; i++) {
1796                 item_off = btrfs_item_ptr_offset(leaf, i);
1797                 item_len = btrfs_item_size_nr(leaf, i);
1798
1799                 if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1800                         item_len = 0;
1801
1802                 if (sizeof(sh) + item_len + *sk_offset >
1803                     BTRFS_SEARCH_ARGS_BUFSIZE) {
1804                         ret = 1;
1805                         goto overflow;
1806                 }
1807
1808                 btrfs_item_key_to_cpu(leaf, key, i);
1809                 if (!key_in_sk(key, sk))
1810                         continue;
1811
1812                 sh.objectid = key->objectid;
1813                 sh.offset = key->offset;
1814                 sh.type = key->type;
1815                 sh.len = item_len;
1816                 sh.transid = found_transid;
1817
1818                 /* copy search result header */
1819                 memcpy(buf + *sk_offset, &sh, sizeof(sh));
1820                 *sk_offset += sizeof(sh);
1821
1822                 if (item_len) {
1823                         char *p = buf + *sk_offset;
1824                         /* copy the item */
1825                         read_extent_buffer(leaf, p,
1826                                            item_off, item_len);
1827                         *sk_offset += item_len;
1828                 }
1829                 (*num_found)++;
1830
1831                 if (*num_found >= sk->nr_items)
1832                         break;
1833         }
1834 advance_key:
1835         ret = 0;
1836         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1837                 key->offset++;
1838         else if (key->type < (u8)-1 && key->type < sk->max_type) {
1839                 key->offset = 0;
1840                 key->type++;
1841         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1842                 key->offset = 0;
1843                 key->type = 0;
1844                 key->objectid++;
1845         } else
1846                 ret = 1;
1847 overflow:
1848         return ret;
1849 }
1850
1851 static noinline int search_ioctl(struct inode *inode,
1852                                  struct btrfs_ioctl_search_args *args)
1853 {
1854         struct btrfs_root *root;
1855         struct btrfs_key key;
1856         struct btrfs_key max_key;
1857         struct btrfs_path *path;
1858         struct btrfs_ioctl_search_key *sk = &args->key;
1859         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1860         int ret;
1861         int num_found = 0;
1862         unsigned long sk_offset = 0;
1863
1864         path = btrfs_alloc_path();
1865         if (!path)
1866                 return -ENOMEM;
1867
1868         if (sk->tree_id == 0) {
1869                 /* search the root of the inode that was passed */
1870                 root = BTRFS_I(inode)->root;
1871         } else {
1872                 key.objectid = sk->tree_id;
1873                 key.type = BTRFS_ROOT_ITEM_KEY;
1874                 key.offset = (u64)-1;
1875                 root = btrfs_read_fs_root_no_name(info, &key);
1876                 if (IS_ERR(root)) {
1877                         printk(KERN_ERR "could not find root %llu\n",
1878                                sk->tree_id);
1879                         btrfs_free_path(path);
1880                         return -ENOENT;
1881                 }
1882         }
1883
1884         key.objectid = sk->min_objectid;
1885         key.type = sk->min_type;
1886         key.offset = sk->min_offset;
1887
1888         max_key.objectid = sk->max_objectid;
1889         max_key.type = sk->max_type;
1890         max_key.offset = sk->max_offset;
1891
1892         path->keep_locks = 1;
1893
1894         while(1) {
1895                 ret = btrfs_search_forward(root, &key, &max_key, path,
1896                                            sk->min_transid);
1897                 if (ret != 0) {
1898                         if (ret > 0)
1899                                 ret = 0;
1900                         goto err;
1901                 }
1902                 ret = copy_to_sk(root, path, &key, sk, args->buf,
1903                                  &sk_offset, &num_found);
1904                 btrfs_release_path(path);
1905                 if (ret || num_found >= sk->nr_items)
1906                         break;
1907
1908         }
1909         ret = 0;
1910 err:
1911         sk->nr_items = num_found;
1912         btrfs_free_path(path);
1913         return ret;
1914 }
1915
1916 static noinline int btrfs_ioctl_tree_search(struct file *file,
1917                                            void __user *argp)
1918 {
1919          struct btrfs_ioctl_search_args *args;
1920          struct inode *inode;
1921          int ret;
1922
1923         if (!capable(CAP_SYS_ADMIN))
1924                 return -EPERM;
1925
1926         args = memdup_user(argp, sizeof(*args));
1927         if (IS_ERR(args))
1928                 return PTR_ERR(args);
1929
1930         inode = file_inode(file);
1931         ret = search_ioctl(inode, args);
1932         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1933                 ret = -EFAULT;
1934         kfree(args);
1935         return ret;
1936 }
1937
1938 /*
1939  * Search INODE_REFs to identify path name of 'dirid' directory
1940  * in a 'tree_id' tree. and sets path name to 'name'.
1941  */
1942 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1943                                 u64 tree_id, u64 dirid, char *name)
1944 {
1945         struct btrfs_root *root;
1946         struct btrfs_key key;
1947         char *ptr;
1948         int ret = -1;
1949         int slot;
1950         int len;
1951         int total_len = 0;
1952         struct btrfs_inode_ref *iref;
1953         struct extent_buffer *l;
1954         struct btrfs_path *path;
1955
1956         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1957                 name[0]='\0';
1958                 return 0;
1959         }
1960
1961         path = btrfs_alloc_path();
1962         if (!path)
1963                 return -ENOMEM;
1964
1965         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1966
1967         key.objectid = tree_id;
1968         key.type = BTRFS_ROOT_ITEM_KEY;
1969         key.offset = (u64)-1;
1970         root = btrfs_read_fs_root_no_name(info, &key);
1971         if (IS_ERR(root)) {
1972                 printk(KERN_ERR "could not find root %llu\n", tree_id);
1973                 ret = -ENOENT;
1974                 goto out;
1975         }
1976
1977         key.objectid = dirid;
1978         key.type = BTRFS_INODE_REF_KEY;
1979         key.offset = (u64)-1;
1980
1981         while(1) {
1982                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1983                 if (ret < 0)
1984                         goto out;
1985
1986                 l = path->nodes[0];
1987                 slot = path->slots[0];
1988                 if (ret > 0 && slot > 0)
1989                         slot--;
1990                 btrfs_item_key_to_cpu(l, &key, slot);
1991
1992                 if (ret > 0 && (key.objectid != dirid ||
1993                                 key.type != BTRFS_INODE_REF_KEY)) {
1994                         ret = -ENOENT;
1995                         goto out;
1996                 }
1997
1998                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1999                 len = btrfs_inode_ref_name_len(l, iref);
2000                 ptr -= len + 1;
2001                 total_len += len + 1;
2002                 if (ptr < name)
2003                         goto out;
2004
2005                 *(ptr + len) = '/';
2006                 read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
2007
2008                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2009                         break;
2010
2011                 btrfs_release_path(path);
2012                 key.objectid = key.offset;
2013                 key.offset = (u64)-1;
2014                 dirid = key.objectid;
2015         }
2016         if (ptr < name)
2017                 goto out;
2018         memmove(name, ptr, total_len);
2019         name[total_len]='\0';
2020         ret = 0;
2021 out:
2022         btrfs_free_path(path);
2023         return ret;
2024 }
2025
2026 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2027                                            void __user *argp)
2028 {
2029          struct btrfs_ioctl_ino_lookup_args *args;
2030          struct inode *inode;
2031          int ret;
2032
2033         if (!capable(CAP_SYS_ADMIN))
2034                 return -EPERM;
2035
2036         args = memdup_user(argp, sizeof(*args));
2037         if (IS_ERR(args))
2038                 return PTR_ERR(args);
2039
2040         inode = file_inode(file);
2041
2042         if (args->treeid == 0)
2043                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2044
2045         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2046                                         args->treeid, args->objectid,
2047                                         args->name);
2048
2049         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2050                 ret = -EFAULT;
2051
2052         kfree(args);
2053         return ret;
2054 }
2055
2056 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2057                                              void __user *arg)
2058 {
2059         struct dentry *parent = fdentry(file);
2060         struct dentry *dentry;
2061         struct inode *dir = parent->d_inode;
2062         struct inode *inode;
2063         struct btrfs_root *root = BTRFS_I(dir)->root;
2064         struct btrfs_root *dest = NULL;
2065         struct btrfs_ioctl_vol_args *vol_args;
2066         struct btrfs_trans_handle *trans;
2067         struct btrfs_block_rsv block_rsv;
2068         u64 qgroup_reserved;
2069         int namelen;
2070         int ret;
2071         int err = 0;
2072
2073         vol_args = memdup_user(arg, sizeof(*vol_args));
2074         if (IS_ERR(vol_args))
2075                 return PTR_ERR(vol_args);
2076
2077         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2078         namelen = strlen(vol_args->name);
2079         if (strchr(vol_args->name, '/') ||
2080             strncmp(vol_args->name, "..", namelen) == 0) {
2081                 err = -EINVAL;
2082                 goto out;
2083         }
2084
2085         err = mnt_want_write_file(file);
2086         if (err)
2087                 goto out;
2088
2089         mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
2090         dentry = lookup_one_len(vol_args->name, parent, namelen);
2091         if (IS_ERR(dentry)) {
2092                 err = PTR_ERR(dentry);
2093                 goto out_unlock_dir;
2094         }
2095
2096         if (!dentry->d_inode) {
2097                 err = -ENOENT;
2098                 goto out_dput;
2099         }
2100
2101         inode = dentry->d_inode;
2102         dest = BTRFS_I(inode)->root;
2103         if (!capable(CAP_SYS_ADMIN)){
2104                 /*
2105                  * Regular user.  Only allow this with a special mount
2106                  * option, when the user has write+exec access to the
2107                  * subvol root, and when rmdir(2) would have been
2108                  * allowed.
2109                  *
2110                  * Note that this is _not_ check that the subvol is
2111                  * empty or doesn't contain data that we wouldn't
2112                  * otherwise be able to delete.
2113                  *
2114                  * Users who want to delete empty subvols should try
2115                  * rmdir(2).
2116                  */
2117                 err = -EPERM;
2118                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2119                         goto out_dput;
2120
2121                 /*
2122                  * Do not allow deletion if the parent dir is the same
2123                  * as the dir to be deleted.  That means the ioctl
2124                  * must be called on the dentry referencing the root
2125                  * of the subvol, not a random directory contained
2126                  * within it.
2127                  */
2128                 err = -EINVAL;
2129                 if (root == dest)
2130                         goto out_dput;
2131
2132                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2133                 if (err)
2134                         goto out_dput;
2135         }
2136
2137         /* check if subvolume may be deleted by a user */
2138         err = btrfs_may_delete(dir, dentry, 1);
2139         if (err)
2140                 goto out_dput;
2141
2142         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2143                 err = -EINVAL;
2144                 goto out_dput;
2145         }
2146
2147         mutex_lock(&inode->i_mutex);
2148         err = d_invalidate(dentry);
2149         if (err)
2150                 goto out_unlock;
2151
2152         down_write(&root->fs_info->subvol_sem);
2153
2154         err = may_destroy_subvol(dest);
2155         if (err)
2156                 goto out_up_write;
2157
2158         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2159         /*
2160          * One for dir inode, two for dir entries, two for root
2161          * ref/backref.
2162          */
2163         err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2164                                                5, &qgroup_reserved);
2165         if (err)
2166                 goto out_up_write;
2167
2168         trans = btrfs_start_transaction(root, 0);
2169         if (IS_ERR(trans)) {
2170                 err = PTR_ERR(trans);
2171                 goto out_release;
2172         }
2173         trans->block_rsv = &block_rsv;
2174         trans->bytes_reserved = block_rsv.size;
2175
2176         ret = btrfs_unlink_subvol(trans, root, dir,
2177                                 dest->root_key.objectid,
2178                                 dentry->d_name.name,
2179                                 dentry->d_name.len);
2180         if (ret) {
2181                 err = ret;
2182                 btrfs_abort_transaction(trans, root, ret);
2183                 goto out_end_trans;
2184         }
2185
2186         btrfs_record_root_in_trans(trans, dest);
2187
2188         memset(&dest->root_item.drop_progress, 0,
2189                 sizeof(dest->root_item.drop_progress));
2190         dest->root_item.drop_level = 0;
2191         btrfs_set_root_refs(&dest->root_item, 0);
2192
2193         if (!xchg(&dest->orphan_item_inserted, 1)) {
2194                 ret = btrfs_insert_orphan_item(trans,
2195                                         root->fs_info->tree_root,
2196                                         dest->root_key.objectid);
2197                 if (ret) {
2198                         btrfs_abort_transaction(trans, root, ret);
2199                         err = ret;
2200                         goto out_end_trans;
2201                 }
2202         }
2203 out_end_trans:
2204         trans->block_rsv = NULL;
2205         trans->bytes_reserved = 0;
2206         ret = btrfs_end_transaction(trans, root);
2207         if (ret && !err)
2208                 err = ret;
2209         inode->i_flags |= S_DEAD;
2210 out_release:
2211         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2212 out_up_write:
2213         up_write(&root->fs_info->subvol_sem);
2214 out_unlock:
2215         mutex_unlock(&inode->i_mutex);
2216         if (!err) {
2217                 shrink_dcache_sb(root->fs_info->sb);
2218                 btrfs_invalidate_inodes(dest);
2219                 d_delete(dentry);
2220
2221                 /* the last ref */
2222                 if (dest->cache_inode) {
2223                         iput(dest->cache_inode);
2224                         dest->cache_inode = NULL;
2225                 }
2226         }
2227 out_dput:
2228         dput(dentry);
2229 out_unlock_dir:
2230         mutex_unlock(&dir->i_mutex);
2231         mnt_drop_write_file(file);
2232 out:
2233         kfree(vol_args);
2234         return err;
2235 }
2236
2237 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2238 {
2239         struct inode *inode = file_inode(file);
2240         struct btrfs_root *root = BTRFS_I(inode)->root;
2241         struct btrfs_ioctl_defrag_range_args *range;
2242         int ret;
2243
2244         ret = mnt_want_write_file(file);
2245         if (ret)
2246                 return ret;
2247
2248         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2249                         1)) {
2250                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2251                 mnt_drop_write_file(file);
2252                 return -EINVAL;
2253         }
2254
2255         if (btrfs_root_readonly(root)) {
2256                 ret = -EROFS;
2257                 goto out;
2258         }
2259
2260         switch (inode->i_mode & S_IFMT) {
2261         case S_IFDIR:
2262                 if (!capable(CAP_SYS_ADMIN)) {
2263                         ret = -EPERM;
2264                         goto out;
2265                 }
2266                 ret = btrfs_defrag_root(root);
2267                 if (ret)
2268                         goto out;
2269                 ret = btrfs_defrag_root(root->fs_info->extent_root);
2270                 break;
2271         case S_IFREG:
2272                 if (!(file->f_mode & FMODE_WRITE)) {
2273                         ret = -EINVAL;
2274                         goto out;
2275                 }
2276
2277                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2278                 if (!range) {
2279                         ret = -ENOMEM;
2280                         goto out;
2281                 }
2282
2283                 if (argp) {
2284                         if (copy_from_user(range, argp,
2285                                            sizeof(*range))) {
2286                                 ret = -EFAULT;
2287                                 kfree(range);
2288                                 goto out;
2289                         }
2290                         /* compression requires us to start the IO */
2291                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2292                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2293                                 range->extent_thresh = (u32)-1;
2294                         }
2295                 } else {
2296                         /* the rest are all set to zero by kzalloc */
2297                         range->len = (u64)-1;
2298                 }
2299                 ret = btrfs_defrag_file(file_inode(file), file,
2300                                         range, 0, 0);
2301                 if (ret > 0)
2302                         ret = 0;
2303                 kfree(range);
2304                 break;
2305         default:
2306                 ret = -EINVAL;
2307         }
2308 out:
2309         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2310         mnt_drop_write_file(file);
2311         return ret;
2312 }
2313
2314 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2315 {
2316         struct btrfs_ioctl_vol_args *vol_args;
2317         int ret;
2318
2319         if (!capable(CAP_SYS_ADMIN))
2320                 return -EPERM;
2321
2322         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2323                         1)) {
2324                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2325                 return -EINVAL;
2326         }
2327
2328         mutex_lock(&root->fs_info->volume_mutex);
2329         vol_args = memdup_user(arg, sizeof(*vol_args));
2330         if (IS_ERR(vol_args)) {
2331                 ret = PTR_ERR(vol_args);
2332                 goto out;
2333         }
2334
2335         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2336         ret = btrfs_init_new_device(root, vol_args->name);
2337
2338         kfree(vol_args);
2339 out:
2340         mutex_unlock(&root->fs_info->volume_mutex);
2341         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2342         return ret;
2343 }
2344
2345 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2346 {
2347         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2348         struct btrfs_ioctl_vol_args *vol_args;
2349         int ret;
2350
2351         if (!capable(CAP_SYS_ADMIN))
2352                 return -EPERM;
2353
2354         ret = mnt_want_write_file(file);
2355         if (ret)
2356                 return ret;
2357
2358         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2359                         1)) {
2360                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2361                 mnt_drop_write_file(file);
2362                 return -EINVAL;
2363         }
2364
2365         mutex_lock(&root->fs_info->volume_mutex);
2366         vol_args = memdup_user(arg, sizeof(*vol_args));
2367         if (IS_ERR(vol_args)) {
2368                 ret = PTR_ERR(vol_args);
2369                 goto out;
2370         }
2371
2372         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2373         ret = btrfs_rm_device(root, vol_args->name);
2374
2375         kfree(vol_args);
2376 out:
2377         mutex_unlock(&root->fs_info->volume_mutex);
2378         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2379         mnt_drop_write_file(file);
2380         return ret;
2381 }
2382
2383 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2384 {
2385         struct btrfs_ioctl_fs_info_args *fi_args;
2386         struct btrfs_device *device;
2387         struct btrfs_device *next;
2388         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2389         int ret = 0;
2390
2391         if (!capable(CAP_SYS_ADMIN))
2392                 return -EPERM;
2393
2394         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2395         if (!fi_args)
2396                 return -ENOMEM;
2397
2398         fi_args->num_devices = fs_devices->num_devices;
2399         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2400
2401         mutex_lock(&fs_devices->device_list_mutex);
2402         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2403                 if (device->devid > fi_args->max_id)
2404                         fi_args->max_id = device->devid;
2405         }
2406         mutex_unlock(&fs_devices->device_list_mutex);
2407
2408         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2409                 ret = -EFAULT;
2410
2411         kfree(fi_args);
2412         return ret;
2413 }
2414
2415 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2416 {
2417         struct btrfs_ioctl_dev_info_args *di_args;
2418         struct btrfs_device *dev;
2419         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2420         int ret = 0;
2421         char *s_uuid = NULL;
2422         char empty_uuid[BTRFS_UUID_SIZE] = {0};
2423
2424         if (!capable(CAP_SYS_ADMIN))
2425                 return -EPERM;
2426
2427         di_args = memdup_user(arg, sizeof(*di_args));
2428         if (IS_ERR(di_args))
2429                 return PTR_ERR(di_args);
2430
2431         if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2432                 s_uuid = di_args->uuid;
2433
2434         mutex_lock(&fs_devices->device_list_mutex);
2435         dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2436         mutex_unlock(&fs_devices->device_list_mutex);
2437
2438         if (!dev) {
2439                 ret = -ENODEV;
2440                 goto out;
2441         }
2442
2443         di_args->devid = dev->devid;
2444         di_args->bytes_used = dev->bytes_used;
2445         di_args->total_bytes = dev->total_bytes;
2446         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2447         if (dev->name) {
2448                 struct rcu_string *name;
2449
2450                 rcu_read_lock();
2451                 name = rcu_dereference(dev->name);
2452                 strncpy(di_args->path, name->str, sizeof(di_args->path));
2453                 rcu_read_unlock();
2454                 di_args->path[sizeof(di_args->path) - 1] = 0;
2455         } else {
2456                 di_args->path[0] = '\0';
2457         }
2458
2459 out:
2460         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2461                 ret = -EFAULT;
2462
2463         kfree(di_args);
2464         return ret;
2465 }
2466
2467 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2468                                        u64 off, u64 olen, u64 destoff)
2469 {
2470         struct inode *inode = file_inode(file);
2471         struct btrfs_root *root = BTRFS_I(inode)->root;
2472         struct fd src_file;
2473         struct inode *src;
2474         struct btrfs_trans_handle *trans;
2475         struct btrfs_path *path;
2476         struct extent_buffer *leaf;
2477         char *buf;
2478         struct btrfs_key key;
2479         u32 nritems;
2480         int slot;
2481         int ret;
2482         u64 len = olen;
2483         u64 bs = root->fs_info->sb->s_blocksize;
2484
2485         /*
2486          * TODO:
2487          * - split compressed inline extents.  annoying: we need to
2488          *   decompress into destination's address_space (the file offset
2489          *   may change, so source mapping won't do), then recompress (or
2490          *   otherwise reinsert) a subrange.
2491          * - allow ranges within the same file to be cloned (provided
2492          *   they don't overlap)?
2493          */
2494
2495         /* the destination must be opened for writing */
2496         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2497                 return -EINVAL;
2498
2499         if (btrfs_root_readonly(root))
2500                 return -EROFS;
2501
2502         ret = mnt_want_write_file(file);
2503         if (ret)
2504                 return ret;
2505
2506         src_file = fdget(srcfd);
2507         if (!src_file.file) {
2508                 ret = -EBADF;
2509                 goto out_drop_write;
2510         }
2511
2512         ret = -EXDEV;
2513         if (src_file.file->f_path.mnt != file->f_path.mnt)
2514                 goto out_fput;
2515
2516         src = file_inode(src_file.file);
2517
2518         ret = -EINVAL;
2519         if (src == inode)
2520                 goto out_fput;
2521
2522         /* the src must be open for reading */
2523         if (!(src_file.file->f_mode & FMODE_READ))
2524                 goto out_fput;
2525
2526         /* don't make the dst file partly checksummed */
2527         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2528             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2529                 goto out_fput;
2530
2531         ret = -EISDIR;
2532         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2533                 goto out_fput;
2534
2535         ret = -EXDEV;
2536         if (src->i_sb != inode->i_sb)
2537                 goto out_fput;
2538
2539         ret = -ENOMEM;
2540         buf = vmalloc(btrfs_level_size(root, 0));
2541         if (!buf)
2542                 goto out_fput;
2543
2544         path = btrfs_alloc_path();
2545         if (!path) {
2546                 vfree(buf);
2547                 goto out_fput;
2548         }
2549         path->reada = 2;
2550
2551         if (inode < src) {
2552                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2553                 mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2554         } else {
2555                 mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2556                 mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2557         }
2558
2559         /* determine range to clone */
2560         ret = -EINVAL;
2561         if (off + len > src->i_size || off + len < off)
2562                 goto out_unlock;
2563         if (len == 0)
2564                 olen = len = src->i_size - off;
2565         /* if we extend to eof, continue to block boundary */
2566         if (off + len == src->i_size)
2567                 len = ALIGN(src->i_size, bs) - off;
2568
2569         /* verify the end result is block aligned */
2570         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2571             !IS_ALIGNED(destoff, bs))
2572                 goto out_unlock;
2573
2574         if (destoff > inode->i_size) {
2575                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2576                 if (ret)
2577                         goto out_unlock;
2578         }
2579
2580         /* truncate page cache pages from target inode range */
2581         truncate_inode_pages_range(&inode->i_data, destoff,
2582                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
2583
2584         /* do any pending delalloc/csum calc on src, one way or
2585            another, and lock file content */
2586         while (1) {
2587                 struct btrfs_ordered_extent *ordered;
2588                 lock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2589                 ordered = btrfs_lookup_first_ordered_extent(src, off + len - 1);
2590                 if (!ordered &&
2591                     !test_range_bit(&BTRFS_I(src)->io_tree, off, off + len - 1,
2592                                     EXTENT_DELALLOC, 0, NULL))
2593                         break;
2594                 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2595                 if (ordered)
2596                         btrfs_put_ordered_extent(ordered);
2597                 btrfs_wait_ordered_range(src, off, len);
2598         }
2599
2600         /* clone data */
2601         key.objectid = btrfs_ino(src);
2602         key.type = BTRFS_EXTENT_DATA_KEY;
2603         key.offset = 0;
2604
2605         while (1) {
2606                 /*
2607                  * note the key will change type as we walk through the
2608                  * tree.
2609                  */
2610                 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
2611                                 0, 0);
2612                 if (ret < 0)
2613                         goto out;
2614
2615                 nritems = btrfs_header_nritems(path->nodes[0]);
2616                 if (path->slots[0] >= nritems) {
2617                         ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
2618                         if (ret < 0)
2619                                 goto out;
2620                         if (ret > 0)
2621                                 break;
2622                         nritems = btrfs_header_nritems(path->nodes[0]);
2623                 }
2624                 leaf = path->nodes[0];
2625                 slot = path->slots[0];
2626
2627                 btrfs_item_key_to_cpu(leaf, &key, slot);
2628                 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2629                     key.objectid != btrfs_ino(src))
2630                         break;
2631
2632                 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2633                         struct btrfs_file_extent_item *extent;
2634                         int type;
2635                         u32 size;
2636                         struct btrfs_key new_key;
2637                         u64 disko = 0, diskl = 0;
2638                         u64 datao = 0, datal = 0;
2639                         u8 comp;
2640                         u64 endoff;
2641
2642                         size = btrfs_item_size_nr(leaf, slot);
2643                         read_extent_buffer(leaf, buf,
2644                                            btrfs_item_ptr_offset(leaf, slot),
2645                                            size);
2646
2647                         extent = btrfs_item_ptr(leaf, slot,
2648                                                 struct btrfs_file_extent_item);
2649                         comp = btrfs_file_extent_compression(leaf, extent);
2650                         type = btrfs_file_extent_type(leaf, extent);
2651                         if (type == BTRFS_FILE_EXTENT_REG ||
2652                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2653                                 disko = btrfs_file_extent_disk_bytenr(leaf,
2654                                                                       extent);
2655                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
2656                                                                  extent);
2657                                 datao = btrfs_file_extent_offset(leaf, extent);
2658                                 datal = btrfs_file_extent_num_bytes(leaf,
2659                                                                     extent);
2660                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2661                                 /* take upper bound, may be compressed */
2662                                 datal = btrfs_file_extent_ram_bytes(leaf,
2663                                                                     extent);
2664                         }
2665                         btrfs_release_path(path);
2666
2667                         if (key.offset + datal <= off ||
2668                             key.offset >= off + len - 1)
2669                                 goto next;
2670
2671                         memcpy(&new_key, &key, sizeof(new_key));
2672                         new_key.objectid = btrfs_ino(inode);
2673                         if (off <= key.offset)
2674                                 new_key.offset = key.offset + destoff - off;
2675                         else
2676                                 new_key.offset = destoff;
2677
2678                         /*
2679                          * 1 - adjusting old extent (we may have to split it)
2680                          * 1 - add new extent
2681                          * 1 - inode update
2682                          */
2683                         trans = btrfs_start_transaction(root, 3);
2684                         if (IS_ERR(trans)) {
2685                                 ret = PTR_ERR(trans);
2686                                 goto out;
2687                         }
2688
2689                         if (type == BTRFS_FILE_EXTENT_REG ||
2690                             type == BTRFS_FILE_EXTENT_PREALLOC) {
2691                                 /*
2692                                  *    a  | --- range to clone ---|  b
2693                                  * | ------------- extent ------------- |
2694                                  */
2695
2696                                 /* substract range b */
2697                                 if (key.offset + datal > off + len)
2698                                         datal = off + len - key.offset;
2699
2700                                 /* substract range a */
2701                                 if (off > key.offset) {
2702                                         datao += off - key.offset;
2703                                         datal -= off - key.offset;
2704                                 }
2705
2706                                 ret = btrfs_drop_extents(trans, root, inode,
2707                                                          new_key.offset,
2708                                                          new_key.offset + datal,
2709                                                          1);
2710                                 if (ret) {
2711                                         btrfs_abort_transaction(trans, root,
2712                                                                 ret);
2713                                         btrfs_end_transaction(trans, root);
2714                                         goto out;
2715                                 }
2716
2717                                 ret = btrfs_insert_empty_item(trans, root, path,
2718                                                               &new_key, size);
2719                                 if (ret) {
2720                                         btrfs_abort_transaction(trans, root,
2721                                                                 ret);
2722                                         btrfs_end_transaction(trans, root);
2723                                         goto out;
2724                                 }
2725
2726                                 leaf = path->nodes[0];
2727                                 slot = path->slots[0];
2728                                 write_extent_buffer(leaf, buf,
2729                                             btrfs_item_ptr_offset(leaf, slot),
2730                                             size);
2731
2732                                 extent = btrfs_item_ptr(leaf, slot,
2733                                                 struct btrfs_file_extent_item);
2734
2735                                 /* disko == 0 means it's a hole */
2736                                 if (!disko)
2737                                         datao = 0;
2738
2739                                 btrfs_set_file_extent_offset(leaf, extent,
2740                                                              datao);
2741                                 btrfs_set_file_extent_num_bytes(leaf, extent,
2742                                                                 datal);
2743                                 if (disko) {
2744                                         inode_add_bytes(inode, datal);
2745                                         ret = btrfs_inc_extent_ref(trans, root,
2746                                                         disko, diskl, 0,
2747                                                         root->root_key.objectid,
2748                                                         btrfs_ino(inode),
2749                                                         new_key.offset - datao,
2750                                                         0);
2751                                         if (ret) {
2752                                                 btrfs_abort_transaction(trans,
2753                                                                         root,
2754                                                                         ret);
2755                                                 btrfs_end_transaction(trans,
2756                                                                       root);
2757                                                 goto out;
2758
2759                                         }
2760                                 }
2761                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
2762                                 u64 skip = 0;
2763                                 u64 trim = 0;
2764                                 if (off > key.offset) {
2765                                         skip = off - key.offset;
2766                                         new_key.offset += skip;
2767                                 }
2768
2769                                 if (key.offset + datal > off + len)
2770                                         trim = key.offset + datal - (off + len);
2771
2772                                 if (comp && (skip || trim)) {
2773                                         ret = -EINVAL;
2774                                         btrfs_end_transaction(trans, root);
2775                                         goto out;
2776                                 }
2777                                 size -= skip + trim;
2778                                 datal -= skip + trim;
2779
2780                                 ret = btrfs_drop_extents(trans, root, inode,
2781                                                          new_key.offset,
2782                                                          new_key.offset + datal,
2783                                                          1);
2784                                 if (ret) {
2785                                         btrfs_abort_transaction(trans, root,
2786                                                                 ret);
2787                                         btrfs_end_transaction(trans, root);
2788                                         goto out;
2789                                 }
2790
2791                                 ret = btrfs_insert_empty_item(trans, root, path,
2792                                                               &new_key, size);
2793                                 if (ret) {
2794                                         btrfs_abort_transaction(trans, root,
2795                                                                 ret);
2796                                         btrfs_end_transaction(trans, root);
2797                                         goto out;
2798                                 }
2799
2800                                 if (skip) {
2801                                         u32 start =
2802                                           btrfs_file_extent_calc_inline_size(0);
2803                                         memmove(buf+start, buf+start+skip,
2804                                                 datal);
2805                                 }
2806
2807                                 leaf = path->nodes[0];
2808                                 slot = path->slots[0];
2809                                 write_extent_buffer(leaf, buf,
2810                                             btrfs_item_ptr_offset(leaf, slot),
2811                                             size);
2812                                 inode_add_bytes(inode, datal);
2813                         }
2814
2815                         btrfs_mark_buffer_dirty(leaf);
2816                         btrfs_release_path(path);
2817
2818                         inode_inc_iversion(inode);
2819                         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2820
2821                         /*
2822                          * we round up to the block size at eof when
2823                          * determining which extents to clone above,
2824                          * but shouldn't round up the file size
2825                          */
2826                         endoff = new_key.offset + datal;
2827                         if (endoff > destoff+olen)
2828                                 endoff = destoff+olen;
2829                         if (endoff > inode->i_size)
2830                                 btrfs_i_size_write(inode, endoff);
2831
2832                         ret = btrfs_update_inode(trans, root, inode);
2833                         if (ret) {
2834                                 btrfs_abort_transaction(trans, root, ret);
2835                                 btrfs_end_transaction(trans, root);
2836                                 goto out;
2837                         }
2838                         ret = btrfs_end_transaction(trans, root);
2839                 }
2840 next:
2841                 btrfs_release_path(path);
2842                 key.offset++;
2843         }
2844         ret = 0;
2845 out:
2846         btrfs_release_path(path);
2847         unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
2848 out_unlock:
2849         mutex_unlock(&src->i_mutex);
2850         mutex_unlock(&inode->i_mutex);
2851         vfree(buf);
2852         btrfs_free_path(path);
2853 out_fput:
2854         fdput(src_file);
2855 out_drop_write:
2856         mnt_drop_write_file(file);
2857         return ret;
2858 }
2859
2860 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2861 {
2862         struct btrfs_ioctl_clone_range_args args;
2863
2864         if (copy_from_user(&args, argp, sizeof(args)))
2865                 return -EFAULT;
2866         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2867                                  args.src_length, args.dest_offset);
2868 }
2869
2870 /*
2871  * there are many ways the trans_start and trans_end ioctls can lead
2872  * to deadlocks.  They should only be used by applications that
2873  * basically own the machine, and have a very in depth understanding
2874  * of all the possible deadlocks and enospc problems.
2875  */
2876 static long btrfs_ioctl_trans_start(struct file *file)
2877 {
2878         struct inode *inode = file_inode(file);
2879         struct btrfs_root *root = BTRFS_I(inode)->root;
2880         struct btrfs_trans_handle *trans;
2881         int ret;
2882
2883         ret = -EPERM;
2884         if (!capable(CAP_SYS_ADMIN))
2885                 goto out;
2886
2887         ret = -EINPROGRESS;
2888         if (file->private_data)
2889                 goto out;
2890
2891         ret = -EROFS;
2892         if (btrfs_root_readonly(root))
2893                 goto out;
2894
2895         ret = mnt_want_write_file(file);
2896         if (ret)
2897                 goto out;
2898
2899         atomic_inc(&root->fs_info->open_ioctl_trans);
2900
2901         ret = -ENOMEM;
2902         trans = btrfs_start_ioctl_transaction(root);
2903         if (IS_ERR(trans))
2904                 goto out_drop;
2905
2906         file->private_data = trans;
2907         return 0;
2908
2909 out_drop:
2910         atomic_dec(&root->fs_info->open_ioctl_trans);
2911         mnt_drop_write_file(file);
2912 out:
2913         return ret;
2914 }
2915
2916 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2917 {
2918         struct inode *inode = file_inode(file);
2919         struct btrfs_root *root = BTRFS_I(inode)->root;
2920         struct btrfs_root *new_root;
2921         struct btrfs_dir_item *di;
2922         struct btrfs_trans_handle *trans;
2923         struct btrfs_path *path;
2924         struct btrfs_key location;
2925         struct btrfs_disk_key disk_key;
2926         u64 objectid = 0;
2927         u64 dir_id;
2928         int ret;
2929
2930         if (!capable(CAP_SYS_ADMIN))
2931                 return -EPERM;
2932
2933         ret = mnt_want_write_file(file);
2934         if (ret)
2935                 return ret;
2936
2937         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
2938                 ret = -EFAULT;
2939                 goto out;
2940         }
2941
2942         if (!objectid)
2943                 objectid = root->root_key.objectid;
2944
2945         location.objectid = objectid;
2946         location.type = BTRFS_ROOT_ITEM_KEY;
2947         location.offset = (u64)-1;
2948
2949         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2950         if (IS_ERR(new_root)) {
2951                 ret = PTR_ERR(new_root);
2952                 goto out;
2953         }
2954
2955         if (btrfs_root_refs(&new_root->root_item) == 0) {
2956                 ret = -ENOENT;
2957                 goto out;
2958         }
2959
2960         path = btrfs_alloc_path();
2961         if (!path) {
2962                 ret = -ENOMEM;
2963                 goto out;
2964         }
2965         path->leave_spinning = 1;
2966
2967         trans = btrfs_start_transaction(root, 1);
2968         if (IS_ERR(trans)) {
2969                 btrfs_free_path(path);
2970                 ret = PTR_ERR(trans);
2971                 goto out;
2972         }
2973
2974         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2975         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2976                                    dir_id, "default", 7, 1);
2977         if (IS_ERR_OR_NULL(di)) {
2978                 btrfs_free_path(path);
2979                 btrfs_end_transaction(trans, root);
2980                 printk(KERN_ERR "Umm, you don't have the default dir item, "
2981                        "this isn't going to work\n");
2982                 ret = -ENOENT;
2983                 goto out;
2984         }
2985
2986         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2987         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2988         btrfs_mark_buffer_dirty(path->nodes[0]);
2989         btrfs_free_path(path);
2990
2991         btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
2992         btrfs_end_transaction(trans, root);
2993 out:
2994         mnt_drop_write_file(file);
2995         return ret;
2996 }
2997
2998 void btrfs_get_block_group_info(struct list_head *groups_list,
2999                                 struct btrfs_ioctl_space_info *space)
3000 {
3001         struct btrfs_block_group_cache *block_group;
3002
3003         space->total_bytes = 0;
3004         space->used_bytes = 0;
3005         space->flags = 0;
3006         list_for_each_entry(block_group, groups_list, list) {
3007                 space->flags = block_group->flags;
3008                 space->total_bytes += block_group->key.offset;
3009                 space->used_bytes +=
3010                         btrfs_block_group_used(&block_group->item);
3011         }
3012 }
3013
3014 long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3015 {
3016         struct btrfs_ioctl_space_args space_args;
3017         struct btrfs_ioctl_space_info space;
3018         struct btrfs_ioctl_space_info *dest;
3019         struct btrfs_ioctl_space_info *dest_orig;
3020         struct btrfs_ioctl_space_info __user *user_dest;
3021         struct btrfs_space_info *info;
3022         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3023                        BTRFS_BLOCK_GROUP_SYSTEM,
3024                        BTRFS_BLOCK_GROUP_METADATA,
3025                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3026         int num_types = 4;
3027         int alloc_size;
3028         int ret = 0;
3029         u64 slot_count = 0;
3030         int i, c;
3031
3032         if (copy_from_user(&space_args,
3033                            (struct btrfs_ioctl_space_args __user *)arg,
3034                            sizeof(space_args)))
3035                 return -EFAULT;
3036
3037         for (i = 0; i < num_types; i++) {
3038                 struct btrfs_space_info *tmp;
3039
3040                 info = NULL;
3041                 rcu_read_lock();
3042                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3043                                         list) {
3044                         if (tmp->flags == types[i]) {
3045                                 info = tmp;
3046                                 break;
3047                         }
3048                 }
3049                 rcu_read_unlock();
3050
3051                 if (!info)
3052                         continue;
3053
3054                 down_read(&info->groups_sem);
3055                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3056                         if (!list_empty(&info->block_groups[c]))
3057                                 slot_count++;
3058                 }
3059                 up_read(&info->groups_sem);
3060         }
3061
3062         /* space_slots == 0 means they are asking for a count */
3063         if (space_args.space_slots == 0) {
3064                 space_args.total_spaces = slot_count;
3065                 goto out;
3066         }
3067
3068         slot_count = min_t(u64, space_args.space_slots, slot_count);
3069
3070         alloc_size = sizeof(*dest) * slot_count;
3071
3072         /* we generally have at most 6 or so space infos, one for each raid
3073          * level.  So, a whole page should be more than enough for everyone
3074          */
3075         if (alloc_size > PAGE_CACHE_SIZE)
3076                 return -ENOMEM;
3077
3078         space_args.total_spaces = 0;
3079         dest = kmalloc(alloc_size, GFP_NOFS);
3080         if (!dest)
3081                 return -ENOMEM;
3082         dest_orig = dest;
3083
3084         /* now we have a buffer to copy into */
3085         for (i = 0; i < num_types; i++) {
3086                 struct btrfs_space_info *tmp;
3087
3088                 if (!slot_count)
3089                         break;
3090
3091                 info = NULL;
3092                 rcu_read_lock();
3093                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3094                                         list) {
3095                         if (tmp->flags == types[i]) {
3096                                 info = tmp;
3097                                 break;
3098                         }
3099                 }
3100                 rcu_read_unlock();
3101
3102                 if (!info)
3103                         continue;
3104                 down_read(&info->groups_sem);
3105                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3106                         if (!list_empty(&info->block_groups[c])) {
3107                                 btrfs_get_block_group_info(
3108                                         &info->block_groups[c], &space);
3109                                 memcpy(dest, &space, sizeof(space));
3110                                 dest++;
3111                                 space_args.total_spaces++;
3112                                 slot_count--;
3113                         }
3114                         if (!slot_count)
3115                                 break;
3116                 }
3117                 up_read(&info->groups_sem);
3118         }
3119
3120         user_dest = (struct btrfs_ioctl_space_info __user *)
3121                 (arg + sizeof(struct btrfs_ioctl_space_args));
3122
3123         if (copy_to_user(user_dest, dest_orig, alloc_size))
3124                 ret = -EFAULT;
3125
3126         kfree(dest_orig);
3127 out:
3128         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3129                 ret = -EFAULT;
3130
3131         return ret;
3132 }
3133
3134 /*
3135  * there are many ways the trans_start and trans_end ioctls can lead
3136  * to deadlocks.  They should only be used by applications that
3137  * basically own the machine, and have a very in depth understanding
3138  * of all the possible deadlocks and enospc problems.
3139  */
3140 long btrfs_ioctl_trans_end(struct file *file)
3141 {
3142         struct inode *inode = file_inode(file);
3143         struct btrfs_root *root = BTRFS_I(inode)->root;
3144         struct btrfs_trans_handle *trans;
3145
3146         trans = file->private_data;
3147         if (!trans)
3148                 return -EINVAL;
3149         file->private_data = NULL;
3150
3151         btrfs_end_transaction(trans, root);
3152
3153         atomic_dec(&root->fs_info->open_ioctl_trans);
3154
3155         mnt_drop_write_file(file);
3156         return 0;
3157 }
3158
3159 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3160                                             void __user *argp)
3161 {
3162         struct btrfs_trans_handle *trans;
3163         u64 transid;
3164         int ret;
3165
3166         trans = btrfs_attach_transaction_barrier(root);
3167         if (IS_ERR(trans)) {
3168                 if (PTR_ERR(trans) != -ENOENT)
3169                         return PTR_ERR(trans);
3170
3171                 /* No running transaction, don't bother */
3172                 transid = root->fs_info->last_trans_committed;
3173                 goto out;
3174         }
3175         transid = trans->transid;
3176         ret = btrfs_commit_transaction_async(trans, root, 0);
3177         if (ret) {
3178                 btrfs_end_transaction(trans, root);
3179                 return ret;
3180         }
3181 out:
3182         if (argp)
3183                 if (copy_to_user(argp, &transid, sizeof(transid)))
3184                         return -EFAULT;
3185         return 0;
3186 }
3187
3188 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
3189                                            void __user *argp)
3190 {
3191         u64 transid;
3192
3193         if (argp) {
3194                 if (copy_from_user(&transid, argp, sizeof(transid)))
3195                         return -EFAULT;
3196         } else {
3197                 transid = 0;  /* current trans */
3198         }
3199         return btrfs_wait_for_commit(root, transid);
3200 }
3201
3202 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3203 {
3204         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3205         struct btrfs_ioctl_scrub_args *sa;
3206         int ret;
3207
3208         if (!capable(CAP_SYS_ADMIN))
3209                 return -EPERM;
3210
3211         sa = memdup_user(arg, sizeof(*sa));
3212         if (IS_ERR(sa))
3213                 return PTR_ERR(sa);
3214
3215         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3216                 ret = mnt_want_write_file(file);
3217                 if (ret)
3218                         goto out;
3219         }
3220
3221         ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3222                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3223                               0);
3224
3225         if (copy_to_user(arg, sa, sizeof(*sa)))
3226                 ret = -EFAULT;
3227
3228         if (!(sa->flags & BTRFS_SCRUB_READONLY))
3229                 mnt_drop_write_file(file);
3230 out:
3231         kfree(sa);
3232         return ret;
3233 }
3234
3235 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3236 {
3237         if (!capable(CAP_SYS_ADMIN))
3238                 return -EPERM;
3239
3240         return btrfs_scrub_cancel(root->fs_info);
3241 }
3242
3243 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3244                                        void __user *arg)
3245 {
3246         struct btrfs_ioctl_scrub_args *sa;
3247         int ret;
3248
3249         if (!capable(CAP_SYS_ADMIN))
3250                 return -EPERM;
3251
3252         sa = memdup_user(arg, sizeof(*sa));
3253         if (IS_ERR(sa))
3254                 return PTR_ERR(sa);
3255
3256         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3257
3258         if (copy_to_user(arg, sa, sizeof(*sa)))
3259                 ret = -EFAULT;
3260
3261         kfree(sa);
3262         return ret;
3263 }
3264
3265 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3266                                       void __user *arg)
3267 {
3268         struct btrfs_ioctl_get_dev_stats *sa;
3269         int ret;
3270
3271         sa = memdup_user(arg, sizeof(*sa));
3272         if (IS_ERR(sa))
3273                 return PTR_ERR(sa);
3274
3275         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3276                 kfree(sa);
3277                 return -EPERM;
3278         }
3279
3280         ret = btrfs_get_dev_stats(root, sa);
3281
3282         if (copy_to_user(arg, sa, sizeof(*sa)))
3283                 ret = -EFAULT;
3284
3285         kfree(sa);
3286         return ret;
3287 }
3288
3289 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
3290 {
3291         struct btrfs_ioctl_dev_replace_args *p;
3292         int ret;
3293
3294         if (!capable(CAP_SYS_ADMIN))
3295                 return -EPERM;
3296
3297         p = memdup_user(arg, sizeof(*p));
3298         if (IS_ERR(p))
3299                 return PTR_ERR(p);
3300
3301         switch (p->cmd) {
3302         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3303                 if (atomic_xchg(
3304                         &root->fs_info->mutually_exclusive_operation_running,
3305                         1)) {
3306                         pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3307                         ret = -EINPROGRESS;
3308                 } else {
3309                         ret = btrfs_dev_replace_start(root, p);
3310                         atomic_set(
3311                          &root->fs_info->mutually_exclusive_operation_running,
3312                          0);
3313                 }
3314                 break;
3315         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3316                 btrfs_dev_replace_status(root->fs_info, p);
3317                 ret = 0;
3318                 break;
3319         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3320                 ret = btrfs_dev_replace_cancel(root->fs_info, p);
3321                 break;
3322         default:
3323                 ret = -EINVAL;
3324                 break;
3325         }
3326
3327         if (copy_to_user(arg, p, sizeof(*p)))
3328                 ret = -EFAULT;
3329
3330         kfree(p);
3331         return ret;
3332 }
3333
3334 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3335 {
3336         int ret = 0;
3337         int i;
3338         u64 rel_ptr;
3339         int size;
3340         struct btrfs_ioctl_ino_path_args *ipa = NULL;
3341         struct inode_fs_paths *ipath = NULL;
3342         struct btrfs_path *path;
3343
3344         if (!capable(CAP_DAC_READ_SEARCH))
3345                 return -EPERM;
3346
3347         path = btrfs_alloc_path();
3348         if (!path) {
3349                 ret = -ENOMEM;
3350                 goto out;
3351         }
3352
3353         ipa = memdup_user(arg, sizeof(*ipa));
3354         if (IS_ERR(ipa)) {
3355                 ret = PTR_ERR(ipa);
3356                 ipa = NULL;
3357                 goto out;
3358         }
3359
3360         size = min_t(u32, ipa->size, 4096);
3361         ipath = init_ipath(size, root, path);
3362         if (IS_ERR(ipath)) {
3363                 ret = PTR_ERR(ipath);
3364                 ipath = NULL;
3365                 goto out;
3366         }
3367
3368         ret = paths_from_inode(ipa->inum, ipath);
3369         if (ret < 0)
3370                 goto out;
3371
3372         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3373                 rel_ptr = ipath->fspath->val[i] -
3374                           (u64)(unsigned long)ipath->fspath->val;
3375                 ipath->fspath->val[i] = rel_ptr;
3376         }
3377
3378         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3379                            (void *)(unsigned long)ipath->fspath, size);
3380         if (ret) {
3381                 ret = -EFAULT;
3382                 goto out;
3383         }
3384
3385 out:
3386         btrfs_free_path(path);
3387         free_ipath(ipath);
3388         kfree(ipa);
3389
3390         return ret;
3391 }
3392
3393 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3394 {
3395         struct btrfs_data_container *inodes = ctx;
3396         const size_t c = 3 * sizeof(u64);
3397
3398         if (inodes->bytes_left >= c) {
3399                 inodes->bytes_left -= c;
3400                 inodes->val[inodes->elem_cnt] = inum;
3401                 inodes->val[inodes->elem_cnt + 1] = offset;
3402                 inodes->val[inodes->elem_cnt + 2] = root;
3403                 inodes->elem_cnt += 3;
3404         } else {
3405                 inodes->bytes_missing += c - inodes->bytes_left;
3406                 inodes->bytes_left = 0;
3407                 inodes->elem_missed += 3;
3408         }
3409
3410         return 0;
3411 }
3412
3413 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3414                                         void __user *arg)
3415 {
3416         int ret = 0;
3417         int size;
3418         struct btrfs_ioctl_logical_ino_args *loi;
3419         struct btrfs_data_container *inodes = NULL;
3420         struct btrfs_path *path = NULL;
3421
3422         if (!capable(CAP_SYS_ADMIN))
3423                 return -EPERM;
3424
3425         loi = memdup_user(arg, sizeof(*loi));
3426         if (IS_ERR(loi)) {
3427                 ret = PTR_ERR(loi);
3428                 loi = NULL;
3429                 goto out;
3430         }
3431
3432         path = btrfs_alloc_path();
3433         if (!path) {
3434                 ret = -ENOMEM;
3435                 goto out;
3436         }
3437
3438         size = min_t(u32, loi->size, 64 * 1024);
3439         inodes = init_data_container(size);
3440         if (IS_ERR(inodes)) {
3441                 ret = PTR_ERR(inodes);
3442                 inodes = NULL;
3443                 goto out;
3444         }
3445
3446         ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
3447                                           build_ino_list, inodes);
3448         if (ret == -EINVAL)
3449                 ret = -ENOENT;
3450         if (ret < 0)
3451                 goto out;
3452
3453         ret = copy_to_user((void *)(unsigned long)loi->inodes,
3454                            (void *)(unsigned long)inodes, size);
3455         if (ret)
3456                 ret = -EFAULT;
3457
3458 out:
3459         btrfs_free_path(path);
3460         vfree(inodes);
3461         kfree(loi);
3462
3463         return ret;
3464 }
3465
3466 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3467                                struct btrfs_ioctl_balance_args *bargs)
3468 {
3469         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3470
3471         bargs->flags = bctl->flags;
3472
3473         if (atomic_read(&fs_info->balance_running))
3474                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3475         if (atomic_read(&fs_info->balance_pause_req))
3476                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3477         if (atomic_read(&fs_info->balance_cancel_req))
3478                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3479
3480         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3481         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3482         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3483
3484         if (lock) {
3485                 spin_lock(&fs_info->balance_lock);
3486                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3487                 spin_unlock(&fs_info->balance_lock);
3488         } else {
3489                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3490         }
3491 }
3492
3493 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3494 {
3495         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3496         struct btrfs_fs_info *fs_info = root->fs_info;
3497         struct btrfs_ioctl_balance_args *bargs;
3498         struct btrfs_balance_control *bctl;
3499         bool need_unlock; /* for mut. excl. ops lock */
3500         int ret;
3501
3502         if (!capable(CAP_SYS_ADMIN))
3503                 return -EPERM;
3504
3505         ret = mnt_want_write_file(file);
3506         if (ret)
3507                 return ret;
3508
3509 again:
3510         if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
3511                 mutex_lock(&fs_info->volume_mutex);
3512                 mutex_lock(&fs_info->balance_mutex);
3513                 need_unlock = true;
3514                 goto locked;
3515         }
3516
3517         /*
3518          * mut. excl. ops lock is locked.  Three possibilites:
3519          *   (1) some other op is running
3520          *   (2) balance is running
3521          *   (3) balance is paused -- special case (think resume)
3522          */
3523         mutex_lock(&fs_info->balance_mutex);
3524         if (fs_info->balance_ctl) {
3525                 /* this is either (2) or (3) */
3526                 if (!atomic_read(&fs_info->balance_running)) {
3527                         mutex_unlock(&fs_info->balance_mutex);
3528                         if (!mutex_trylock(&fs_info->volume_mutex))
3529                                 goto again;
3530                         mutex_lock(&fs_info->balance_mutex);
3531
3532                         if (fs_info->balance_ctl &&
3533                             !atomic_read(&fs_info->balance_running)) {
3534                                 /* this is (3) */
3535                                 need_unlock = false;
3536                                 goto locked;
3537                         }
3538
3539                         mutex_unlock(&fs_info->balance_mutex);
3540                         mutex_unlock(&fs_info->volume_mutex);
3541                         goto again;
3542                 } else {
3543                         /* this is (2) */
3544                         mutex_unlock(&fs_info->balance_mutex);
3545                         ret = -EINPROGRESS;
3546                         goto out;
3547                 }
3548         } else {
3549                 /* this is (1) */
3550                 mutex_unlock(&fs_info->balance_mutex);
3551                 pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
3552                 ret = -EINVAL;
3553                 goto out;
3554         }
3555
3556 locked:
3557         BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
3558
3559         if (arg) {
3560                 bargs = memdup_user(arg, sizeof(*bargs));
3561                 if (IS_ERR(bargs)) {
3562                         ret = PTR_ERR(bargs);
3563                         goto out_unlock;
3564                 }
3565
3566                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
3567                         if (!fs_info->balance_ctl) {
3568                                 ret = -ENOTCONN;
3569                                 goto out_bargs;
3570                         }
3571
3572                         bctl = fs_info->balance_ctl;
3573                         spin_lock(&fs_info->balance_lock);
3574                         bctl->flags |= BTRFS_BALANCE_RESUME;
3575                         spin_unlock(&fs_info->balance_lock);
3576
3577                         goto do_balance;
3578                 }
3579         } else {
3580                 bargs = NULL;
3581         }
3582
3583         if (fs_info->balance_ctl) {
3584                 ret = -EINPROGRESS;
3585                 goto out_bargs;
3586         }
3587
3588         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3589         if (!bctl) {
3590                 ret = -ENOMEM;
3591                 goto out_bargs;
3592         }
3593
3594         bctl->fs_info = fs_info;
3595         if (arg) {
3596                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3597                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3598                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3599
3600                 bctl->flags = bargs->flags;
3601         } else {
3602                 /* balance everything - no filters */
3603                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3604         }
3605
3606 do_balance:
3607         /*
3608          * Ownership of bctl and mutually_exclusive_operation_running
3609          * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
3610          * or, if restriper was paused all the way until unmount, in
3611          * free_fs_info.  mutually_exclusive_operation_running is
3612          * cleared in __cancel_balance.
3613          */
3614         need_unlock = false;
3615
3616         ret = btrfs_balance(bctl, bargs);
3617
3618         if (arg) {
3619                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
3620                         ret = -EFAULT;
3621         }
3622
3623 out_bargs:
3624         kfree(bargs);
3625 out_unlock:
3626         mutex_unlock(&fs_info->balance_mutex);
3627         mutex_unlock(&fs_info->volume_mutex);
3628         if (need_unlock)
3629                 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
3630 out:
3631         mnt_drop_write_file(file);
3632         return ret;
3633 }
3634
3635 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3636 {
3637         if (!capable(CAP_SYS_ADMIN))
3638                 return -EPERM;
3639
3640         switch (cmd) {
3641         case BTRFS_BALANCE_CTL_PAUSE:
3642                 return btrfs_pause_balance(root->fs_info);
3643         case BTRFS_BALANCE_CTL_CANCEL:
3644                 return btrfs_cancel_balance(root->fs_info);
3645         }
3646
3647         return -EINVAL;
3648 }
3649
3650 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3651                                          void __user *arg)
3652 {
3653         struct btrfs_fs_info *fs_info = root->fs_info;
3654         struct btrfs_ioctl_balance_args *bargs;
3655         int ret = 0;
3656
3657         if (!capable(CAP_SYS_ADMIN))
3658                 return -EPERM;
3659
3660         mutex_lock(&fs_info->balance_mutex);
3661         if (!fs_info->balance_ctl) {
3662                 ret = -ENOTCONN;
3663                 goto out;
3664         }
3665
3666         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3667         if (!bargs) {
3668                 ret = -ENOMEM;
3669                 goto out;
3670         }
3671
3672         update_ioctl_balance_args(fs_info, 1, bargs);
3673
3674         if (copy_to_user(arg, bargs, sizeof(*bargs)))
3675                 ret = -EFAULT;
3676
3677         kfree(bargs);
3678 out:
3679         mutex_unlock(&fs_info->balance_mutex);
3680         return ret;
3681 }
3682
3683 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
3684 {
3685         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3686         struct btrfs_ioctl_quota_ctl_args *sa;
3687         struct btrfs_trans_handle *trans = NULL;
3688         int ret;
3689         int err;
3690
3691         if (!capable(CAP_SYS_ADMIN))
3692                 return -EPERM;
3693
3694         ret = mnt_want_write_file(file);
3695         if (ret)
3696                 return ret;
3697
3698         sa = memdup_user(arg, sizeof(*sa));
3699         if (IS_ERR(sa)) {
3700                 ret = PTR_ERR(sa);
3701                 goto drop_write;
3702         }
3703
3704         if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
3705                 trans = btrfs_start_transaction(root, 2);
3706                 if (IS_ERR(trans)) {
3707                         ret = PTR_ERR(trans);
3708                         goto out;
3709                 }
3710         }
3711
3712         switch (sa->cmd) {
3713         case BTRFS_QUOTA_CTL_ENABLE:
3714                 ret = btrfs_quota_enable(trans, root->fs_info);
3715                 break;
3716         case BTRFS_QUOTA_CTL_DISABLE:
3717                 ret = btrfs_quota_disable(trans, root->fs_info);
3718                 break;
3719         case BTRFS_QUOTA_CTL_RESCAN:
3720                 ret = btrfs_quota_rescan(root->fs_info);
3721                 break;
3722         default:
3723                 ret = -EINVAL;
3724                 break;
3725         }
3726
3727         if (copy_to_user(arg, sa, sizeof(*sa)))
3728                 ret = -EFAULT;
3729
3730         if (trans) {
3731                 err = btrfs_commit_transaction(trans, root);
3732                 if (err && !ret)
3733                         ret = err;
3734         }
3735 out:
3736         kfree(sa);
3737 drop_write:
3738         mnt_drop_write_file(file);
3739         return ret;
3740 }
3741
3742 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
3743 {
3744         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3745         struct btrfs_ioctl_qgroup_assign_args *sa;
3746         struct btrfs_trans_handle *trans;
3747         int ret;
3748         int err;
3749
3750         if (!capable(CAP_SYS_ADMIN))
3751                 return -EPERM;
3752
3753         ret = mnt_want_write_file(file);
3754         if (ret)
3755                 return ret;
3756
3757         sa = memdup_user(arg, sizeof(*sa));
3758         if (IS_ERR(sa)) {
3759                 ret = PTR_ERR(sa);
3760                 goto drop_write;
3761         }
3762
3763         trans = btrfs_join_transaction(root);
3764         if (IS_ERR(trans)) {
3765                 ret = PTR_ERR(trans);
3766                 goto out;
3767         }
3768
3769         /* FIXME: check if the IDs really exist */
3770         if (sa->assign) {
3771                 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
3772                                                 sa->src, sa->dst);
3773         } else {
3774                 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
3775                                                 sa->src, sa->dst);
3776         }
3777
3778         err = btrfs_end_transaction(trans, root);
3779         if (err && !ret)
3780                 ret = err;
3781
3782 out:
3783         kfree(sa);
3784 drop_write:
3785         mnt_drop_write_file(file);
3786         return ret;
3787 }
3788
3789 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
3790 {
3791         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3792         struct btrfs_ioctl_qgroup_create_args *sa;
3793         struct btrfs_trans_handle *trans;
3794         int ret;
3795         int err;
3796
3797         if (!capable(CAP_SYS_ADMIN))
3798                 return -EPERM;
3799
3800         ret = mnt_want_write_file(file);
3801         if (ret)
3802                 return ret;
3803
3804         sa = memdup_user(arg, sizeof(*sa));
3805         if (IS_ERR(sa)) {
3806                 ret = PTR_ERR(sa);
3807                 goto drop_write;
3808         }
3809
3810         if (!sa->qgroupid) {
3811                 ret = -EINVAL;
3812                 goto out;
3813         }
3814
3815         trans = btrfs_join_transaction(root);
3816         if (IS_ERR(trans)) {
3817                 ret = PTR_ERR(trans);
3818                 goto out;
3819         }
3820
3821         /* FIXME: check if the IDs really exist */
3822         if (sa->create) {
3823                 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
3824                                           NULL);
3825         } else {
3826                 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
3827         }
3828
3829         err = btrfs_end_transaction(trans, root);
3830         if (err && !ret)
3831                 ret = err;
3832
3833 out:
3834         kfree(sa);
3835 drop_write:
3836         mnt_drop_write_file(file);
3837         return ret;
3838 }
3839
3840 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
3841 {
3842         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3843         struct btrfs_ioctl_qgroup_limit_args *sa;
3844         struct btrfs_trans_handle *trans;
3845         int ret;
3846         int err;
3847         u64 qgroupid;
3848
3849         if (!capable(CAP_SYS_ADMIN))
3850                 return -EPERM;
3851
3852         ret = mnt_want_write_file(file);
3853         if (ret)
3854                 return ret;
3855
3856         sa = memdup_user(arg, sizeof(*sa));
3857         if (IS_ERR(sa)) {
3858                 ret = PTR_ERR(sa);
3859                 goto drop_write;
3860         }
3861
3862         trans = btrfs_join_transaction(root);
3863         if (IS_ERR(trans)) {
3864                 ret = PTR_ERR(trans);
3865                 goto out;
3866         }
3867
3868         qgroupid = sa->qgroupid;
3869         if (!qgroupid) {
3870                 /* take the current subvol as qgroup */
3871                 qgroupid = root->root_key.objectid;
3872         }
3873
3874         /* FIXME: check if the IDs really exist */
3875         ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
3876
3877         err = btrfs_end_transaction(trans, root);
3878         if (err && !ret)
3879                 ret = err;
3880
3881 out:
3882         kfree(sa);
3883 drop_write:
3884         mnt_drop_write_file(file);
3885         return ret;
3886 }
3887
3888 static long btrfs_ioctl_set_received_subvol(struct file *file,
3889                                             void __user *arg)
3890 {
3891         struct btrfs_ioctl_received_subvol_args *sa = NULL;
3892         struct inode *inode = file_inode(file);
3893         struct btrfs_root *root = BTRFS_I(inode)->root;
3894         struct btrfs_root_item *root_item = &root->root_item;
3895         struct btrfs_trans_handle *trans;
3896         struct timespec ct = CURRENT_TIME;
3897         int ret = 0;
3898
3899         ret = mnt_want_write_file(file);
3900         if (ret < 0)
3901                 return ret;
3902
3903         down_write(&root->fs_info->subvol_sem);
3904
3905         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
3906                 ret = -EINVAL;
3907                 goto out;
3908         }
3909
3910         if (btrfs_root_readonly(root)) {
3911                 ret = -EROFS;
3912                 goto out;
3913         }
3914
3915         if (!inode_owner_or_capable(inode)) {
3916                 ret = -EACCES;
3917                 goto out;
3918         }
3919
3920         sa = memdup_user(arg, sizeof(*sa));
3921         if (IS_ERR(sa)) {
3922                 ret = PTR_ERR(sa);
3923                 sa = NULL;
3924                 goto out;
3925         }
3926
3927         trans = btrfs_start_transaction(root, 1);
3928         if (IS_ERR(trans)) {
3929                 ret = PTR_ERR(trans);
3930                 trans = NULL;
3931                 goto out;
3932         }
3933
3934         sa->rtransid = trans->transid;
3935         sa->rtime.sec = ct.tv_sec;
3936         sa->rtime.nsec = ct.tv_nsec;
3937
3938         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
3939         btrfs_set_root_stransid(root_item, sa->stransid);
3940         btrfs_set_root_rtransid(root_item, sa->rtransid);
3941         root_item->stime.sec = cpu_to_le64(sa->stime.sec);
3942         root_item->stime.nsec = cpu_to_le32(sa->stime.nsec);
3943         root_item->rtime.sec = cpu_to_le64(sa->rtime.sec);
3944         root_item->rtime.nsec = cpu_to_le32(sa->rtime.nsec);
3945
3946         ret = btrfs_update_root(trans, root->fs_info->tree_root,
3947                                 &root->root_key, &root->root_item);
3948         if (ret < 0) {
3949                 btrfs_end_transaction(trans, root);
3950                 trans = NULL;
3951                 goto out;
3952         } else {
3953                 ret = btrfs_commit_transaction(trans, root);
3954                 if (ret < 0)
3955                         goto out;
3956         }
3957
3958         ret = copy_to_user(arg, sa, sizeof(*sa));
3959         if (ret)
3960                 ret = -EFAULT;
3961
3962 out:
3963         kfree(sa);
3964         up_write(&root->fs_info->subvol_sem);
3965         mnt_drop_write_file(file);
3966         return ret;
3967 }
3968
3969 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
3970 {
3971         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3972         const char *label = root->fs_info->super_copy->label;
3973         size_t len = strnlen(label, BTRFS_LABEL_SIZE);
3974         int ret;
3975
3976         if (len == BTRFS_LABEL_SIZE) {
3977                 pr_warn("btrfs: label is too long, return the first %zu bytes\n",
3978                         --len);
3979         }
3980
3981         mutex_lock(&root->fs_info->volume_mutex);
3982         ret = copy_to_user(arg, label, len);
3983         mutex_unlock(&root->fs_info->volume_mutex);
3984
3985         return ret ? -EFAULT : 0;
3986 }
3987
3988 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
3989 {
3990         struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3991         struct btrfs_super_block *super_block = root->fs_info->super_copy;
3992         struct btrfs_trans_handle *trans;
3993         char label[BTRFS_LABEL_SIZE];
3994         int ret;
3995
3996         if (!capable(CAP_SYS_ADMIN))
3997                 return -EPERM;
3998
3999         if (copy_from_user(label, arg, sizeof(label)))
4000                 return -EFAULT;
4001
4002         if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4003                 pr_err("btrfs: unable to set label with more than %d bytes\n",
4004                        BTRFS_LABEL_SIZE - 1);
4005                 return -EINVAL;
4006         }
4007
4008         ret = mnt_want_write_file(file);
4009         if (ret)
4010                 return ret;
4011
4012         mutex_lock(&root->fs_info->volume_mutex);
4013         trans = btrfs_start_transaction(root, 0);
4014         if (IS_ERR(trans)) {
4015                 ret = PTR_ERR(trans);
4016                 goto out_unlock;
4017         }
4018
4019         strcpy(super_block->label, label);
4020         ret = btrfs_end_transaction(trans, root);
4021
4022 out_unlock:
4023         mutex_unlock(&root->fs_info->volume_mutex);
4024         mnt_drop_write_file(file);
4025         return ret;
4026 }
4027
4028 long btrfs_ioctl(struct file *file, unsigned int
4029                 cmd, unsigned long arg)
4030 {
4031         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4032         void __user *argp = (void __user *)arg;
4033
4034         switch (cmd) {
4035         case FS_IOC_GETFLAGS:
4036                 return btrfs_ioctl_getflags(file, argp);
4037         case FS_IOC_SETFLAGS:
4038                 return btrfs_ioctl_setflags(file, argp);
4039         case FS_IOC_GETVERSION:
4040                 return btrfs_ioctl_getversion(file, argp);
4041         case FITRIM:
4042                 return btrfs_ioctl_fitrim(file, argp);
4043         case BTRFS_IOC_SNAP_CREATE:
4044                 return btrfs_ioctl_snap_create(file, argp, 0);
4045         case BTRFS_IOC_SNAP_CREATE_V2:
4046                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4047         case BTRFS_IOC_SUBVOL_CREATE:
4048                 return btrfs_ioctl_snap_create(file, argp, 1);
4049         case BTRFS_IOC_SUBVOL_CREATE_V2:
4050                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4051         case BTRFS_IOC_SNAP_DESTROY:
4052                 return btrfs_ioctl_snap_destroy(file, argp);
4053         case BTRFS_IOC_SUBVOL_GETFLAGS:
4054                 return btrfs_ioctl_subvol_getflags(file, argp);
4055         case BTRFS_IOC_SUBVOL_SETFLAGS:
4056                 return btrfs_ioctl_subvol_setflags(file, argp);
4057         case BTRFS_IOC_DEFAULT_SUBVOL:
4058                 return btrfs_ioctl_default_subvol(file, argp);
4059         case BTRFS_IOC_DEFRAG:
4060                 return btrfs_ioctl_defrag(file, NULL);
4061         case BTRFS_IOC_DEFRAG_RANGE:
4062                 return btrfs_ioctl_defrag(file, argp);
4063         case BTRFS_IOC_RESIZE:
4064                 return btrfs_ioctl_resize(file, argp);
4065         case BTRFS_IOC_ADD_DEV:
4066                 return btrfs_ioctl_add_dev(root, argp);
4067         case BTRFS_IOC_RM_DEV:
4068                 return btrfs_ioctl_rm_dev(file, argp);
4069         case BTRFS_IOC_FS_INFO:
4070                 return btrfs_ioctl_fs_info(root, argp);
4071         case BTRFS_IOC_DEV_INFO:
4072                 return btrfs_ioctl_dev_info(root, argp);
4073         case BTRFS_IOC_BALANCE:
4074                 return btrfs_ioctl_balance(file, NULL);
4075         case BTRFS_IOC_CLONE:
4076                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
4077         case BTRFS_IOC_CLONE_RANGE:
4078                 return btrfs_ioctl_clone_range(file, argp);
4079         case BTRFS_IOC_TRANS_START:
4080                 return btrfs_ioctl_trans_start(file);
4081         case BTRFS_IOC_TRANS_END:
4082                 return btrfs_ioctl_trans_end(file);
4083         case BTRFS_IOC_TREE_SEARCH:
4084                 return btrfs_ioctl_tree_search(file, argp);
4085         case BTRFS_IOC_INO_LOOKUP:
4086                 return btrfs_ioctl_ino_lookup(file, argp);
4087         case BTRFS_IOC_INO_PATHS:
4088                 return btrfs_ioctl_ino_to_path(root, argp);
4089         case BTRFS_IOC_LOGICAL_INO:
4090                 return btrfs_ioctl_logical_to_ino(root, argp);
4091         case BTRFS_IOC_SPACE_INFO:
4092                 return btrfs_ioctl_space_info(root, argp);
4093         case BTRFS_IOC_SYNC:
4094                 btrfs_sync_fs(file->f_dentry->d_sb, 1);
4095                 return 0;
4096         case BTRFS_IOC_START_SYNC:
4097                 return btrfs_ioctl_start_sync(root, argp);
4098         case BTRFS_IOC_WAIT_SYNC:
4099                 return btrfs_ioctl_wait_sync(root, argp);
4100         case BTRFS_IOC_SCRUB:
4101                 return btrfs_ioctl_scrub(file, argp);
4102         case BTRFS_IOC_SCRUB_CANCEL:
4103                 return btrfs_ioctl_scrub_cancel(root, argp);
4104         case BTRFS_IOC_SCRUB_PROGRESS:
4105                 return btrfs_ioctl_scrub_progress(root, argp);
4106         case BTRFS_IOC_BALANCE_V2:
4107                 return btrfs_ioctl_balance(file, argp);
4108         case BTRFS_IOC_BALANCE_CTL:
4109                 return btrfs_ioctl_balance_ctl(root, arg);
4110         case BTRFS_IOC_BALANCE_PROGRESS:
4111                 return btrfs_ioctl_balance_progress(root, argp);
4112         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4113                 return btrfs_ioctl_set_received_subvol(file, argp);
4114         case BTRFS_IOC_SEND:
4115                 return btrfs_ioctl_send(file, argp);
4116         case BTRFS_IOC_GET_DEV_STATS:
4117                 return btrfs_ioctl_get_dev_stats(root, argp);
4118         case BTRFS_IOC_QUOTA_CTL:
4119                 return btrfs_ioctl_quota_ctl(file, argp);
4120         case BTRFS_IOC_QGROUP_ASSIGN:
4121                 return btrfs_ioctl_qgroup_assign(file, argp);
4122         case BTRFS_IOC_QGROUP_CREATE:
4123                 return btrfs_ioctl_qgroup_create(file, argp);
4124         case BTRFS_IOC_QGROUP_LIMIT:
4125                 return btrfs_ioctl_qgroup_limit(file, argp);
4126         case BTRFS_IOC_DEV_REPLACE:
4127                 return btrfs_ioctl_dev_replace(root, argp);
4128         case BTRFS_IOC_GET_FSLABEL:
4129                 return btrfs_ioctl_get_fslabel(file, argp);
4130         case BTRFS_IOC_SET_FSLABEL:
4131                 return btrfs_ioctl_set_fslabel(file, argp);
4132         }
4133
4134         return -ENOTTY;
4135 }