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 <linux/uaccess.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 #include "props.h"
  60 #include "sysfs.h"
  61 #include "qgroup.h"
  62
  63 #ifdef CONFIG_64BIT
  64 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
  65  * structures are incorrect, as the timespec structure from userspace
  66  * is 4 bytes too small. We define these alternatives here to teach
  67  * the kernel about the 32-bit struct packing.
  68  */
  69 struct btrfs_ioctl_timespec_32 {
  70         __u64 sec;
  71         __u32 nsec;
  72 } __attribute__ ((__packed__));
  73
  74 struct btrfs_ioctl_received_subvol_args_32 {
  75         char    uuid[BTRFS_UUID_SIZE];  /* in */
  76         __u64   stransid;               /* in */
  77         __u64   rtransid;               /* out */
  78         struct btrfs_ioctl_timespec_32 stime; /* in */
  79         struct btrfs_ioctl_timespec_32 rtime; /* out */
  80         __u64   flags;                  /* in */
  81         __u64   reserved[16];           /* in */
  82 } __attribute__ ((__packed__));
  83
  84 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
  85                                 struct btrfs_ioctl_received_subvol_args_32)
  86 #endif
  87
  88
  89 static int btrfs_clone(struct inode *src, struct inode *inode,
  90                        u64 off, u64 olen, u64 olen_aligned, u64 destoff);
  91
  92 /* Mask out flags that are inappropriate for the given type of inode. */
  93 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
  94 {
  95         if (S_ISDIR(mode))
  96                 return flags;
  97         else if (S_ISREG(mode))
  98                 return flags & ~FS_DIRSYNC_FL;
  99         else
 100                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
 101 }
 102
 103 /*
 104  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
 105  */
 106 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
 107 {
 108         unsigned int iflags = 0;
 109
 110         if (flags & BTRFS_INODE_SYNC)
 111                 iflags |= FS_SYNC_FL;
 112         if (flags & BTRFS_INODE_IMMUTABLE)
 113                 iflags |= FS_IMMUTABLE_FL;
 114         if (flags & BTRFS_INODE_APPEND)
 115                 iflags |= FS_APPEND_FL;
 116         if (flags & BTRFS_INODE_NODUMP)
 117                 iflags |= FS_NODUMP_FL;
 118         if (flags & BTRFS_INODE_NOATIME)
 119                 iflags |= FS_NOATIME_FL;
 120         if (flags & BTRFS_INODE_DIRSYNC)
 121                 iflags |= FS_DIRSYNC_FL;
 122         if (flags & BTRFS_INODE_NODATACOW)
 123                 iflags |= FS_NOCOW_FL;
 124
 125         if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
 126                 iflags |= FS_COMPR_FL;
 127         else if (flags & BTRFS_INODE_NOCOMPRESS)
 128                 iflags |= FS_NOCOMP_FL;
 129
 130         return iflags;
 131 }
 132
 133 /*
 134  * Update inode->i_flags based on the btrfs internal flags.
 135  */
 136 void btrfs_update_iflags(struct inode *inode)
 137 {
 138         struct btrfs_inode *ip = BTRFS_I(inode);
 139         unsigned int new_fl = 0;
 140
 141         if (ip->flags & BTRFS_INODE_SYNC)
 142                 new_fl |= S_SYNC;
 143         if (ip->flags & BTRFS_INODE_IMMUTABLE)
 144                 new_fl |= S_IMMUTABLE;
 145         if (ip->flags & BTRFS_INODE_APPEND)
 146                 new_fl |= S_APPEND;
 147         if (ip->flags & BTRFS_INODE_NOATIME)
 148                 new_fl |= S_NOATIME;
 149         if (ip->flags & BTRFS_INODE_DIRSYNC)
 150                 new_fl |= S_DIRSYNC;
 151
 152         set_mask_bits(&inode->i_flags,
 153                       S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
 154                       new_fl);
 155 }
 156
 157 /*
 158  * Inherit flags from the parent inode.
 159  *
 160  * Currently only the compression flags and the cow flags are inherited.
 161  */
 162 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 163 {
 164         unsigned int flags;
 165
 166         if (!dir)
 167                 return;
 168
 169         flags = BTRFS_I(dir)->flags;
 170
 171         if (flags & BTRFS_INODE_NOCOMPRESS) {
 172                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 173                 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 174         } else if (flags & BTRFS_INODE_COMPRESS) {
 175                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 176                 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 177         }
 178
 179         if (flags & BTRFS_INODE_NODATACOW) {
 180                 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 181                 if (S_ISREG(inode->i_mode))
 182                         BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
 183         }
 184
 185         btrfs_update_iflags(inode);
 186 }
 187
 188 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 189 {
 190         struct btrfs_inode *ip = BTRFS_I(file_inode(file));
 191         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 192
 193         if (copy_to_user(arg, &flags, sizeof(flags)))
 194                 return -EFAULT;
 195         return 0;
 196 }
 197
 198 static int check_flags(unsigned int flags)
 199 {
 200         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 201                       FS_NOATIME_FL | FS_NODUMP_FL | \
 202                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 203                       FS_NOCOMP_FL | FS_COMPR_FL |
 204                       FS_NOCOW_FL))
 205                 return -EOPNOTSUPP;
 206
 207         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 208                 return -EINVAL;
 209
 210         return 0;
 211 }
 212
 213 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 214 {
 215         struct inode *inode = file_inode(file);
 216         struct btrfs_inode *ip = BTRFS_I(inode);
 217         struct btrfs_root *root = ip->root;
 218         struct btrfs_trans_handle *trans;
 219         unsigned int flags, oldflags;
 220         int ret;
 221         u64 ip_oldflags;
 222         unsigned int i_oldflags;
 223         umode_t mode;
 224
 225         if (!inode_owner_or_capable(inode))
 226                 return -EPERM;
 227
 228         if (btrfs_root_readonly(root))
 229                 return -EROFS;
 230
 231         if (copy_from_user(&flags, arg, sizeof(flags)))
 232                 return -EFAULT;
 233
 234         ret = check_flags(flags);
 235         if (ret)
 236                 return ret;
 237
 238         ret = mnt_want_write_file(file);
 239         if (ret)
 240                 return ret;
 241
 242         mutex_lock(&inode->i_mutex);
 243
 244         ip_oldflags = ip->flags;
 245         i_oldflags = inode->i_flags;
 246         mode = inode->i_mode;
 247
 248         flags = btrfs_mask_flags(inode->i_mode, flags);
 249         oldflags = btrfs_flags_to_ioctl(ip->flags);
 250         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 251                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 252                         ret = -EPERM;
 253                         goto out_unlock;
 254                 }
 255         }
 256
 257         if (flags & FS_SYNC_FL)
 258                 ip->flags |= BTRFS_INODE_SYNC;
 259         else
 260                 ip->flags &= ~BTRFS_INODE_SYNC;
 261         if (flags & FS_IMMUTABLE_FL)
 262                 ip->flags |= BTRFS_INODE_IMMUTABLE;
 263         else
 264                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 265         if (flags & FS_APPEND_FL)
 266                 ip->flags |= BTRFS_INODE_APPEND;
 267         else
 268                 ip->flags &= ~BTRFS_INODE_APPEND;
 269         if (flags & FS_NODUMP_FL)
 270                 ip->flags |= BTRFS_INODE_NODUMP;
 271         else
 272                 ip->flags &= ~BTRFS_INODE_NODUMP;
 273         if (flags & FS_NOATIME_FL)
 274                 ip->flags |= BTRFS_INODE_NOATIME;
 275         else
 276                 ip->flags &= ~BTRFS_INODE_NOATIME;
 277         if (flags & FS_DIRSYNC_FL)
 278                 ip->flags |= BTRFS_INODE_DIRSYNC;
 279         else
 280                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
 281         if (flags & FS_NOCOW_FL) {
 282                 if (S_ISREG(mode)) {
 283                         /*
 284                          * It's safe to turn csums off here, no extents exist.
 285                          * Otherwise we want the flag to reflect the real COW
 286                          * status of the file and will not set it.
 287                          */
 288                         if (inode->i_size == 0)
 289                                 ip->flags |= BTRFS_INODE_NODATACOW
 290                                            | BTRFS_INODE_NODATASUM;
 291                 } else {
 292                         ip->flags |= BTRFS_INODE_NODATACOW;
 293                 }
 294         } else {
 295                 /*
 296                  * Revert back under same assuptions as above
 297                  */
 298                 if (S_ISREG(mode)) {
 299                         if (inode->i_size == 0)
 300                                 ip->flags &= ~(BTRFS_INODE_NODATACOW
 301                                              | BTRFS_INODE_NODATASUM);
 302                 } else {
 303                         ip->flags &= ~BTRFS_INODE_NODATACOW;
 304                 }
 305         }
 306
 307         /*
 308          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 309          * flag may be changed automatically if compression code won't make
 310          * things smaller.
 311          */
 312         if (flags & FS_NOCOMP_FL) {
 313                 ip->flags &= ~BTRFS_INODE_COMPRESS;
 314                 ip->flags |= BTRFS_INODE_NOCOMPRESS;
 315
 316                 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
 317                 if (ret && ret != -ENODATA)
 318                         goto out_drop;
 319         } else if (flags & FS_COMPR_FL) {
 320                 const char *comp;
 321
 322                 ip->flags |= BTRFS_INODE_COMPRESS;
 323                 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 324
 325                 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
 326                         comp = "lzo";
 327                 else
 328                         comp = "zlib";
 329                 ret = btrfs_set_prop(inode, "btrfs.compression",
 330                                      comp, strlen(comp), 0);
 331                 if (ret)
 332                         goto out_drop;
 333
 334         } else {
 335                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 336         }
 337
 338         trans = btrfs_start_transaction(root, 1);
 339         if (IS_ERR(trans)) {
 340                 ret = PTR_ERR(trans);
 341                 goto out_drop;
 342         }
 343
 344         btrfs_update_iflags(inode);
 345         inode_inc_iversion(inode);
 346         inode->i_ctime = CURRENT_TIME;
 347         ret = btrfs_update_inode(trans, root, inode);
 348
 349         btrfs_end_transaction(trans, root);
 350  out_drop:
 351         if (ret) {
 352                 ip->flags = ip_oldflags;
 353                 inode->i_flags = i_oldflags;
 354         }
 355
 356  out_unlock:
 357         mutex_unlock(&inode->i_mutex);
 358         mnt_drop_write_file(file);
 359         return ret;
 360 }
 361
 362 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 363 {
 364         struct inode *inode = file_inode(file);
 365
 366         return put_user(inode->i_generation, arg);
 367 }
 368
 369 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 370 {
 371         struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
 372         struct btrfs_device *device;
 373         struct request_queue *q;
 374         struct fstrim_range range;
 375         u64 minlen = ULLONG_MAX;
 376         u64 num_devices = 0;
 377         u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 378         int ret;
 379
 380         if (!capable(CAP_SYS_ADMIN))
 381                 return -EPERM;
 382
 383         rcu_read_lock();
 384         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 385                                 dev_list) {
 386                 if (!device->bdev)
 387                         continue;
 388                 q = bdev_get_queue(device->bdev);
 389                 if (blk_queue_discard(q)) {
 390                         num_devices++;
 391                         minlen = min((u64)q->limits.discard_granularity,
 392                                      minlen);
 393                 }
 394         }
 395         rcu_read_unlock();
 396
 397         if (!num_devices)
 398                 return -EOPNOTSUPP;
 399         if (copy_from_user(&range, arg, sizeof(range)))
 400                 return -EFAULT;
 401         if (range.start > total_bytes ||
 402             range.len < fs_info->sb->s_blocksize)
 403                 return -EINVAL;
 404
 405         range.len = min(range.len, total_bytes - range.start);
 406         range.minlen = max(range.minlen, minlen);
 407         ret = btrfs_trim_fs(fs_info->tree_root, &range);
 408         if (ret < 0)
 409                 return ret;
 410
 411         if (copy_to_user(arg, &range, sizeof(range)))
 412                 return -EFAULT;
 413
 414         return 0;
 415 }
 416
 417 int btrfs_is_empty_uuid(u8 *uuid)
 418 {
 419         int i;
 420
 421         for (i = 0; i < BTRFS_UUID_SIZE; i++) {
 422                 if (uuid[i])
 423                         return 0;
 424         }
 425         return 1;
 426 }
 427
 428 static noinline int create_subvol(struct inode *dir,
 429                                   struct dentry *dentry,
 430                                   char *name, int namelen,
 431                                   u64 *async_transid,
 432                                   struct btrfs_qgroup_inherit *inherit)
 433 {
 434         struct btrfs_trans_handle *trans;
 435         struct btrfs_key key;
 436         struct btrfs_root_item root_item;
 437         struct btrfs_inode_item *inode_item;
 438         struct extent_buffer *leaf;
 439         struct btrfs_root *root = BTRFS_I(dir)->root;
 440         struct btrfs_root *new_root;
 441         struct btrfs_block_rsv block_rsv;
 442         struct timespec cur_time = CURRENT_TIME;
 443         struct inode *inode;
 444         int ret;
 445         int err;
 446         u64 objectid;
 447         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 448         u64 index = 0;
 449         u64 qgroup_reserved;
 450         uuid_le new_uuid;
 451
 452         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 453         if (ret)
 454                 return ret;
 455
 456         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 457         /*
 458          * The same as the snapshot creation, please see the comment
 459          * of create_snapshot().
 460          */
 461         ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
 462                                                8, &qgroup_reserved, false);
 463         if (ret)
 464                 return ret;
 465
 466         trans = btrfs_start_transaction(root, 0);
 467         if (IS_ERR(trans)) {
 468                 ret = PTR_ERR(trans);
 469                 btrfs_subvolume_release_metadata(root, &block_rsv,
 470                                                  qgroup_reserved);
 471                 return ret;
 472         }
 473         trans->block_rsv = &block_rsv;
 474         trans->bytes_reserved = block_rsv.size;
 475
 476         ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
 477         if (ret)
 478                 goto fail;
 479
 480         leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
 481                                       0, objectid, NULL, 0, 0, 0);
 482         if (IS_ERR(leaf)) {
 483                 ret = PTR_ERR(leaf);
 484                 goto fail;
 485         }
 486
 487         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 488         btrfs_set_header_bytenr(leaf, leaf->start);
 489         btrfs_set_header_generation(leaf, trans->transid);
 490         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 491         btrfs_set_header_owner(leaf, objectid);
 492
 493         write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
 494                             BTRFS_FSID_SIZE);
 495         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 496                             btrfs_header_chunk_tree_uuid(leaf),
 497                             BTRFS_UUID_SIZE);
 498         btrfs_mark_buffer_dirty(leaf);
 499
 500         memset(&root_item, 0, sizeof(root_item));
 501
 502         inode_item = &root_item.inode;
 503         btrfs_set_stack_inode_generation(inode_item, 1);
 504         btrfs_set_stack_inode_size(inode_item, 3);
 505         btrfs_set_stack_inode_nlink(inode_item, 1);
 506         btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
 507         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 508
 509         btrfs_set_root_flags(&root_item, 0);
 510         btrfs_set_root_limit(&root_item, 0);
 511         btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 512
 513         btrfs_set_root_bytenr(&root_item, leaf->start);
 514         btrfs_set_root_generation(&root_item, trans->transid);
 515         btrfs_set_root_level(&root_item, 0);
 516         btrfs_set_root_refs(&root_item, 1);
 517         btrfs_set_root_used(&root_item, leaf->len);
 518         btrfs_set_root_last_snapshot(&root_item, 0);
 519
 520         btrfs_set_root_generation_v2(&root_item,
 521                         btrfs_root_generation(&root_item));
 522         uuid_le_gen(&new_uuid);
 523         memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
 524         btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
 525         btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
 526         root_item.ctime = root_item.otime;
 527         btrfs_set_root_ctransid(&root_item, trans->transid);
 528         btrfs_set_root_otransid(&root_item, trans->transid);
 529
 530         btrfs_tree_unlock(leaf);
 531         free_extent_buffer(leaf);
 532         leaf = NULL;
 533
 534         btrfs_set_root_dirid(&root_item, new_dirid);
 535
 536         key.objectid = objectid;
 537         key.offset = 0;
 538         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 539         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 540                                 &root_item);
 541         if (ret)
 542                 goto fail;
 543
 544         key.offset = (u64)-1;
 545         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 546         if (IS_ERR(new_root)) {
 547                 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 548                 ret = PTR_ERR(new_root);
 549                 goto fail;
 550         }
 551
 552         btrfs_record_root_in_trans(trans, new_root);
 553
 554         ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
 555         if (ret) {
 556                 /* We potentially lose an unused inode item here */
 557                 btrfs_abort_transaction(trans, root, ret);
 558                 goto fail;
 559         }
 560
 561         /*
 562          * insert the directory item
 563          */
 564         ret = btrfs_set_inode_index(dir, &index);
 565         if (ret) {
 566                 btrfs_abort_transaction(trans, root, ret);
 567                 goto fail;
 568         }
 569
 570         ret = btrfs_insert_dir_item(trans, root,
 571                                     name, namelen, dir, &key,
 572                                     BTRFS_FT_DIR, index);
 573         if (ret) {
 574                 btrfs_abort_transaction(trans, root, ret);
 575                 goto fail;
 576         }
 577
 578         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 579         ret = btrfs_update_inode(trans, root, dir);
 580         BUG_ON(ret);
 581
 582         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 583                                  objectid, root->root_key.objectid,
 584                                  btrfs_ino(dir), index, name, namelen);
 585         BUG_ON(ret);
 586
 587         ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
 588                                   root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
 589                                   objectid);
 590         if (ret)
 591                 btrfs_abort_transaction(trans, root, ret);
 592
 593 fail:
 594         trans->block_rsv = NULL;
 595         trans->bytes_reserved = 0;
 596         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 597
 598         if (async_transid) {
 599                 *async_transid = trans->transid;
 600                 err = btrfs_commit_transaction_async(trans, root, 1);
 601                 if (err)
 602                         err = btrfs_commit_transaction(trans, root);
 603         } else {
 604                 err = btrfs_commit_transaction(trans, root);
 605         }
 606         if (err && !ret)
 607                 ret = err;
 608
 609         if (!ret) {
 610                 inode = btrfs_lookup_dentry(dir, dentry);
 611                 if (IS_ERR(inode))
 612                         return PTR_ERR(inode);
 613                 d_instantiate(dentry, inode);
 614         }
 615         return ret;
 616 }
 617
 618 static void btrfs_wait_nocow_write(struct btrfs_root *root)
 619 {
 620         s64 writers;
 621         DEFINE_WAIT(wait);
 622
 623         do {
 624                 prepare_to_wait(&root->subv_writers->wait, &wait,
 625                                 TASK_UNINTERRUPTIBLE);
 626
 627                 writers = percpu_counter_sum(&root->subv_writers->counter);
 628                 if (writers)
 629                         schedule();
 630
 631                 finish_wait(&root->subv_writers->wait, &wait);
 632         } while (writers);
 633 }
 634
 635 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 636                            struct dentry *dentry, char *name, int namelen,
 637                            u64 *async_transid, bool readonly,
 638                            struct btrfs_qgroup_inherit *inherit)
 639 {
 640         struct inode *inode;
 641         struct btrfs_pending_snapshot *pending_snapshot;
 642         struct btrfs_trans_handle *trans;
 643         int ret;
 644
 645         if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
 646                 return -EINVAL;
 647
 648         atomic_inc(&root->will_be_snapshoted);
 649         smp_mb__after_atomic();
 650         btrfs_wait_nocow_write(root);
 651
 652         ret = btrfs_start_delalloc_inodes(root, 0);
 653         if (ret)
 654                 goto out;
 655
 656         btrfs_wait_ordered_extents(root, -1);
 657
 658         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 659         if (!pending_snapshot) {
 660                 ret = -ENOMEM;
 661                 goto out;
 662         }
 663
 664         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 665                              BTRFS_BLOCK_RSV_TEMP);
 666         /*
 667          * 1 - parent dir inode
 668          * 2 - dir entries
 669          * 1 - root item
 670          * 2 - root ref/backref
 671          * 1 - root of snapshot
 672          * 1 - UUID item
 673          */
 674         ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 675                                         &pending_snapshot->block_rsv, 8,
 676                                         &pending_snapshot->qgroup_reserved,
 677                                         false);
 678         if (ret)
 679                 goto free;
 680
 681         pending_snapshot->dentry = dentry;
 682         pending_snapshot->root = root;
 683         pending_snapshot->readonly = readonly;
 684         pending_snapshot->dir = dir;
 685         pending_snapshot->inherit = inherit;
 686
 687         trans = btrfs_start_transaction(root, 0);
 688         if (IS_ERR(trans)) {
 689                 ret = PTR_ERR(trans);
 690                 goto fail;
 691         }
 692
 693         spin_lock(&root->fs_info->trans_lock);
 694         list_add(&pending_snapshot->list,
 695                  &trans->transaction->pending_snapshots);
 696         spin_unlock(&root->fs_info->trans_lock);
 697         if (async_transid) {
 698                 *async_transid = trans->transid;
 699                 ret = btrfs_commit_transaction_async(trans,
 700                                      root->fs_info->extent_root, 1);
 701                 if (ret)
 702                         ret = btrfs_commit_transaction(trans, root);
 703         } else {
 704                 ret = btrfs_commit_transaction(trans,
 705                                                root->fs_info->extent_root);
 706         }
 707         if (ret)
 708                 goto fail;
 709
 710         ret = pending_snapshot->error;
 711         if (ret)
 712                 goto fail;
 713
 714         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 715         if (ret)
 716                 goto fail;
 717
 718         /*
 719          * If orphan cleanup did remove any orphans, it means the tree was
 720          * modified and therefore the commit root is not the same as the
 721          * current root anymore. This is a problem, because send uses the
 722          * commit root and therefore can see inode items that don't exist
 723          * in the current root anymore, and for example make calls to
 724          * btrfs_iget, which will do tree lookups based on the current root
 725          * and not on the commit root. Those lookups will fail, returning a
 726          * -ESTALE error, and making send fail with that error. So make sure
 727          * a send does not see any orphans we have just removed, and that it
 728          * will see the same inodes regardless of whether a transaction
 729          * commit happened before it started (meaning that the commit root
 730          * will be the same as the current root) or not.
 731          */
 732         if (readonly && pending_snapshot->snap->node !=
 733             pending_snapshot->snap->commit_root) {
 734                 trans = btrfs_join_transaction(pending_snapshot->snap);
 735                 if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) {
 736                         ret = PTR_ERR(trans);
 737                         goto fail;
 738                 }
 739                 if (!IS_ERR(trans)) {
 740                         ret = btrfs_commit_transaction(trans,
 741                                                        pending_snapshot->snap);
 742                         if (ret)
 743                                 goto fail;
 744                 }
 745         }
 746
 747         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 748         if (IS_ERR(inode)) {
 749                 ret = PTR_ERR(inode);
 750                 goto fail;
 751         }
 752
 753         d_instantiate(dentry, inode);
 754         ret = 0;
 755 fail:
 756         btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
 757                                          &pending_snapshot->block_rsv,
 758                                          pending_snapshot->qgroup_reserved);
 759 free:
 760         kfree(pending_snapshot);
 761 out:
 762         atomic_dec(&root->will_be_snapshoted);
 763         return ret;
 764 }
 765
 766 /*  copy of check_sticky in fs/namei.c()
 767 * It's inline, so penalty for filesystems that don't use sticky bit is
 768 * minimal.
 769 */
 770 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 771 {
 772         kuid_t fsuid = current_fsuid();
 773
 774         if (!(dir->i_mode & S_ISVTX))
 775                 return 0;
 776         if (uid_eq(inode->i_uid, fsuid))
 777                 return 0;
 778         if (uid_eq(dir->i_uid, fsuid))
 779                 return 0;
 780         return !capable(CAP_FOWNER);
 781 }
 782
 783 /*  copy of may_delete in fs/namei.c()
 784  *      Check whether we can remove a link victim from directory dir, check
 785  *  whether the type of victim is right.
 786  *  1. We can't do it if dir is read-only (done in permission())
 787  *  2. We should have write and exec permissions on dir
 788  *  3. We can't remove anything from append-only dir
 789  *  4. We can't do anything with immutable dir (done in permission())
 790  *  5. If the sticky bit on dir is set we should either
 791  *      a. be owner of dir, or
 792  *      b. be owner of victim, or
 793  *      c. have CAP_FOWNER capability
 794  *  6. If the victim is append-only or immutable we can't do antyhing with
 795  *     links pointing to it.
 796  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 797  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 798  *  9. We can't remove a root or mountpoint.
 799  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 800  *     nfs_async_unlink().
 801  */
 802
 803 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
 804 {
 805         int error;
 806
 807         if (!victim->d_inode)
 808                 return -ENOENT;
 809
 810         BUG_ON(victim->d_parent->d_inode != dir);
 811         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 812
 813         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 814         if (error)
 815                 return error;
 816         if (IS_APPEND(dir))
 817                 return -EPERM;
 818         if (btrfs_check_sticky(dir, victim->d_inode)||
 819                 IS_APPEND(victim->d_inode)||
 820             IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 821                 return -EPERM;
 822         if (isdir) {
 823                 if (!S_ISDIR(victim->d_inode->i_mode))
 824                         return -ENOTDIR;
 825                 if (IS_ROOT(victim))
 826                         return -EBUSY;
 827         } else if (S_ISDIR(victim->d_inode->i_mode))
 828                 return -EISDIR;
 829         if (IS_DEADDIR(dir))
 830                 return -ENOENT;
 831         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 832                 return -EBUSY;
 833         return 0;
 834 }
 835
 836 /* copy of may_create in fs/namei.c() */
 837 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 838 {
 839         if (child->d_inode)
 840                 return -EEXIST;
 841         if (IS_DEADDIR(dir))
 842                 return -ENOENT;
 843         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 844 }
 845
 846 /*
 847  * Create a new subvolume below @parent.  This is largely modeled after
 848  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 849  * inside this filesystem so it's quite a bit simpler.
 850  */
 851 static noinline int btrfs_mksubvol(struct path *parent,
 852                                    char *name, int namelen,
 853                                    struct btrfs_root *snap_src,
 854                                    u64 *async_transid, bool readonly,
 855                                    struct btrfs_qgroup_inherit *inherit)
 856 {
 857         struct inode *dir  = parent->dentry->d_inode;
 858         struct dentry *dentry;
 859         int error;
 860
 861         error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
 862         if (error == -EINTR)
 863                 return error;
 864
 865         dentry = lookup_one_len(name, parent->dentry, namelen);
 866         error = PTR_ERR(dentry);
 867         if (IS_ERR(dentry))
 868                 goto out_unlock;
 869
 870         error = -EEXIST;
 871         if (dentry->d_inode)
 872                 goto out_dput;
 873
 874         error = btrfs_may_create(dir, dentry);
 875         if (error)
 876                 goto out_dput;
 877
 878         /*
 879          * even if this name doesn't exist, we may get hash collisions.
 880          * check for them now when we can safely fail
 881          */
 882         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 883                                                dir->i_ino, name,
 884                                                namelen);
 885         if (error)
 886                 goto out_dput;
 887
 888         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 889
 890         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 891                 goto out_up_read;
 892
 893         if (snap_src) {
 894                 error = create_snapshot(snap_src, dir, dentry, name, namelen,
 895                                         async_transid, readonly, inherit);
 896         } else {
 897                 error = create_subvol(dir, dentry, name, namelen,
 898                                       async_transid, inherit);
 899         }
 900         if (!error)
 901                 fsnotify_mkdir(dir, dentry);
 902 out_up_read:
 903         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 904 out_dput:
 905         dput(dentry);
 906 out_unlock:
 907         mutex_unlock(&dir->i_mutex);
 908         return error;
 909 }
 910
 911 /*
 912  * When we're defragging a range, we don't want to kick it off again
 913  * if it is really just waiting for delalloc to send it down.
 914  * If we find a nice big extent or delalloc range for the bytes in the
 915  * file you want to defrag, we return 0 to let you know to skip this
 916  * part of the file
 917  */
 918 static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
 919 {
 920         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 921         struct extent_map *em = NULL;
 922         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 923         u64 end;
 924
 925         read_lock(&em_tree->lock);
 926         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 927         read_unlock(&em_tree->lock);
 928
 929         if (em) {
 930                 end = extent_map_end(em);
 931                 free_extent_map(em);
 932                 if (end - offset > thresh)
 933                         return 0;
 934         }
 935         /* if we already have a nice delalloc here, just stop */
 936         thresh /= 2;
 937         end = count_range_bits(io_tree, &offset, offset + thresh,
 938                                thresh, EXTENT_DELALLOC, 1);
 939         if (end >= thresh)
 940                 return 0;
 941         return 1;
 942 }
 943
 944 /*
 945  * helper function to walk through a file and find extents
 946  * newer than a specific transid, and smaller than thresh.
 947  *
 948  * This is used by the defragging code to find new and small
 949  * extents
 950  */
 951 static int find_new_extents(struct btrfs_root *root,
 952                             struct inode *inode, u64 newer_than,
 953                             u64 *off, int thresh)
 954 {
 955         struct btrfs_path *path;
 956         struct btrfs_key min_key;
 957         struct extent_buffer *leaf;
 958         struct btrfs_file_extent_item *extent;
 959         int type;
 960         int ret;
 961         u64 ino = btrfs_ino(inode);
 962
 963         path = btrfs_alloc_path();
 964         if (!path)
 965                 return -ENOMEM;
 966
 967         min_key.objectid = ino;
 968         min_key.type = BTRFS_EXTENT_DATA_KEY;
 969         min_key.offset = *off;
 970
 971         while (1) {
 972                 path->keep_locks = 1;
 973                 ret = btrfs_search_forward(root, &min_key, path, newer_than);
 974                 if (ret != 0)
 975                         goto none;
 976                 path->keep_locks = 0;
 977                 btrfs_unlock_up_safe(path, 1);
 978 process_slot:
 979                 if (min_key.objectid != ino)
 980                         goto none;
 981                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 982                         goto none;
 983
 984                 leaf = path->nodes[0];
 985                 extent = btrfs_item_ptr(leaf, path->slots[0],
 986                                         struct btrfs_file_extent_item);
 987
 988                 type = btrfs_file_extent_type(leaf, extent);
 989                 if (type == BTRFS_FILE_EXTENT_REG &&
 990                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 991                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 992                         *off = min_key.offset;
 993                         btrfs_free_path(path);
 994                         return 0;
 995                 }
 996
 997                 path->slots[0]++;
 998                 if (path->slots[0] < btrfs_header_nritems(leaf)) {
 999                         btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1000                         goto process_slot;
1001                 }
1002
1003                 if (min_key.offset == (u64)-1)
1004                         goto none;
1005
1006                 min_key.offset++;
1007                 btrfs_release_path(path);
1008         }
1009 none:
1010         btrfs_free_path(path);
1011         return -ENOENT;
1012 }
1013
1014 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1015 {
1016         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1017         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1018         struct extent_map *em;
1019         u64 len = PAGE_CACHE_SIZE;
1020
1021         /*
1022          * hopefully we have this extent in the tree already, try without
1023          * the full extent lock
1024          */
1025         read_lock(&em_tree->lock);
1026         em = lookup_extent_mapping(em_tree, start, len);
1027         read_unlock(&em_tree->lock);
1028
1029         if (!em) {
1030                 struct extent_state *cached = NULL;
1031                 u64 end = start + len - 1;
1032
1033                 /* get the big lock and read metadata off disk */
1034                 lock_extent_bits(io_tree, start, end, 0, &cached);
1035                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1036                 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1037
1038                 if (IS_ERR(em))
1039                         return NULL;
1040         }
1041
1042         return em;
1043 }
1044
1045 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1046 {
1047         struct extent_map *next;
1048         bool ret = true;
1049
1050         /* this is the last extent */
1051         if (em->start + em->len >= i_size_read(inode))
1052                 return false;
1053
1054         next = defrag_lookup_extent(inode, em->start + em->len);
1055         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE ||
1056             (em->block_start + em->block_len == next->block_start))
1057                 ret = false;
1058
1059         free_extent_map(next);
1060         return ret;
1061 }
1062
1063 static int should_defrag_range(struct inode *inode, u64 start, int thresh,
1064                                u64 *last_len, u64 *skip, u64 *defrag_end,
1065                                int compress)
1066 {
1067         struct extent_map *em;
1068         int ret = 1;
1069         bool next_mergeable = true;
1070
1071         /*
1072          * make sure that once we start defragging an extent, we keep on
1073          * defragging it
1074          */
1075         if (start < *defrag_end)
1076                 return 1;
1077
1078         *skip = 0;
1079
1080         em = defrag_lookup_extent(inode, start);
1081         if (!em)
1082                 return 0;
1083
1084         /* this will cover holes, and inline extents */
1085         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1086                 ret = 0;
1087                 goto out;
1088         }
1089
1090         next_mergeable = defrag_check_next_extent(inode, em);
1091
1092         /*
1093          * we hit a real extent, if it is big or the next extent is not a
1094          * real extent, don't bother defragging it
1095          */
1096         if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1097             (em->len >= thresh || !next_mergeable))
1098                 ret = 0;
1099 out:
1100         /*
1101          * last_len ends up being a counter of how many bytes we've defragged.
1102          * every time we choose not to defrag an extent, we reset *last_len
1103          * so that the next tiny extent will force a defrag.
1104          *
1105          * The end result of this is that tiny extents before a single big
1106          * extent will force at least part of that big extent to be defragged.
1107          */
1108         if (ret) {
1109                 *defrag_end = extent_map_end(em);
1110         } else {
1111                 *last_len = 0;
1112                 *skip = extent_map_end(em);
1113                 *defrag_end = 0;
1114         }
1115
1116         free_extent_map(em);
1117         return ret;
1118 }
1119
1120 /*
1121  * it doesn't do much good to defrag one or two pages
1122  * at a time.  This pulls in a nice chunk of pages
1123  * to COW and defrag.
1124  *
1125  * It also makes sure the delalloc code has enough
1126  * dirty data to avoid making new small extents as part
1127  * of the defrag
1128  *
1129  * It's a good idea to start RA on this range
1130  * before calling this.
1131  */
1132 static int cluster_pages_for_defrag(struct inode *inode,
1133                                     struct page **pages,
1134                                     unsigned long start_index,
1135                                     unsigned long num_pages)
1136 {
1137         unsigned long file_end;
1138         u64 isize = i_size_read(inode);
1139         u64 page_start;
1140         u64 page_end;
1141         u64 page_cnt;
1142         int ret;
1143         int i;
1144         int i_done;
1145         struct btrfs_ordered_extent *ordered;
1146         struct extent_state *cached_state = NULL;
1147         struct extent_io_tree *tree;
1148         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1149
1150         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1151         if (!isize || start_index > file_end)
1152                 return 0;
1153
1154         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1155
1156         ret = btrfs_delalloc_reserve_space(inode,
1157                                            page_cnt << PAGE_CACHE_SHIFT);
1158         if (ret)
1159                 return ret;
1160         i_done = 0;
1161         tree = &BTRFS_I(inode)->io_tree;
1162
1163         /* step one, lock all the pages */
1164         for (i = 0; i < page_cnt; i++) {
1165                 struct page *page;
1166 again:
1167                 page = find_or_create_page(inode->i_mapping,
1168                                            start_index + i, mask);
1169                 if (!page)
1170                         break;
1171
1172                 page_start = page_offset(page);
1173                 page_end = page_start + PAGE_CACHE_SIZE - 1;
1174                 while (1) {
1175                         lock_extent_bits(tree, page_start, page_end,
1176                                          0, &cached_state);
1177                         ordered = btrfs_lookup_ordered_extent(inode,
1178                                                               page_start);
1179                         unlock_extent_cached(tree, page_start, page_end,
1180                                              &cached_state, GFP_NOFS);
1181                         if (!ordered)
1182                                 break;
1183
1184                         unlock_page(page);
1185                         btrfs_start_ordered_extent(inode, ordered, 1);
1186                         btrfs_put_ordered_extent(ordered);
1187                         lock_page(page);
1188                         /*
1189                          * we unlocked the page above, so we need check if
1190                          * it was released or not.
1191                          */
1192                         if (page->mapping != inode->i_mapping) {
1193                                 unlock_page(page);
1194                                 page_cache_release(page);
1195                                 goto again;
1196                         }
1197                 }
1198
1199                 if (!PageUptodate(page)) {
1200                         btrfs_readpage(NULL, page);
1201                         lock_page(page);
1202                         if (!PageUptodate(page)) {
1203                                 unlock_page(page);
1204                                 page_cache_release(page);
1205                                 ret = -EIO;
1206                                 break;
1207                         }
1208                 }
1209
1210                 if (page->mapping != inode->i_mapping) {
1211                         unlock_page(page);
1212                         page_cache_release(page);
1213                         goto again;
1214                 }
1215
1216                 pages[i] = page;
1217                 i_done++;
1218         }
1219         if (!i_done || ret)
1220                 goto out;
1221
1222         if (!(inode->i_sb->s_flags & MS_ACTIVE))
1223                 goto out;
1224
1225         /*
1226          * so now we have a nice long stream of locked
1227          * and up to date pages, lets wait on them
1228          */
1229         for (i = 0; i < i_done; i++)
1230                 wait_on_page_writeback(pages[i]);
1231
1232         page_start = page_offset(pages[0]);
1233         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1234
1235         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1236                          page_start, page_end - 1, 0, &cached_state);
1237         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1238                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1239                           EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1240                           &cached_state, GFP_NOFS);
1241
1242         if (i_done != page_cnt) {
1243                 spin_lock(&BTRFS_I(inode)->lock);
1244                 BTRFS_I(inode)->outstanding_extents++;
1245                 spin_unlock(&BTRFS_I(inode)->lock);
1246                 btrfs_delalloc_release_space(inode,
1247                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1248         }
1249
1250
1251         set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1252                           &cached_state, GFP_NOFS);
1253
1254         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1255                              page_start, page_end - 1, &cached_state,
1256                              GFP_NOFS);
1257
1258         for (i = 0; i < i_done; i++) {
1259                 clear_page_dirty_for_io(pages[i]);
1260                 ClearPageChecked(pages[i]);
1261                 set_page_extent_mapped(pages[i]);
1262                 set_page_dirty(pages[i]);
1263                 unlock_page(pages[i]);
1264                 page_cache_release(pages[i]);
1265         }
1266         return i_done;
1267 out:
1268         for (i = 0; i < i_done; i++) {
1269                 unlock_page(pages[i]);
1270                 page_cache_release(pages[i]);
1271         }
1272         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1273         return ret;
1274
1275 }
1276
1277 int btrfs_defrag_file(struct inode *inode, struct file *file,
1278                       struct btrfs_ioctl_defrag_range_args *range,
1279                       u64 newer_than, unsigned long max_to_defrag)
1280 {
1281         struct btrfs_root *root = BTRFS_I(inode)->root;
1282         struct file_ra_state *ra = NULL;
1283         unsigned long last_index;
1284         u64 isize = i_size_read(inode);
1285         u64 last_len = 0;
1286         u64 skip = 0;
1287         u64 defrag_end = 0;
1288         u64 newer_off = range->start;
1289         unsigned long i;
1290         unsigned long ra_index = 0;
1291         int ret;
1292         int defrag_count = 0;
1293         int compress_type = BTRFS_COMPRESS_ZLIB;
1294         int extent_thresh = range->extent_thresh;
1295         unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1296         unsigned long cluster = max_cluster;
1297         u64 new_align = ~((u64)128 * 1024 - 1);
1298         struct page **pages = NULL;
1299
1300         if (isize == 0)
1301                 return 0;
1302
1303         if (range->start >= isize)
1304                 return -EINVAL;
1305
1306         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1307                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1308                         return -EINVAL;
1309                 if (range->compress_type)
1310                         compress_type = range->compress_type;
1311         }
1312
1313         if (extent_thresh == 0)
1314                 extent_thresh = 256 * 1024;
1315
1316         /*
1317          * if we were not given a file, allocate a readahead
1318          * context
1319          */
1320         if (!file) {
1321                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1322                 if (!ra)
1323                         return -ENOMEM;
1324                 file_ra_state_init(ra, inode->i_mapping);
1325         } else {
1326                 ra = &file->f_ra;
1327         }
1328
1329         pages = kmalloc_array(max_cluster, sizeof(struct page *),
1330                         GFP_NOFS);
1331         if (!pages) {
1332                 ret = -ENOMEM;
1333                 goto out_ra;
1334         }
1335
1336         /* find the last page to defrag */
1337         if (range->start + range->len > range->start) {
1338                 last_index = min_t(u64, isize - 1,
1339                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1340         } else {
1341                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1342         }
1343
1344         if (newer_than) {
1345                 ret = find_new_extents(root, inode, newer_than,
1346                                        &newer_off, 64 * 1024);
1347                 if (!ret) {
1348                         range->start = newer_off;
1349                         /*
1350                          * we always align our defrag to help keep
1351                          * the extents in the file evenly spaced
1352                          */
1353                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1354                 } else
1355                         goto out_ra;
1356         } else {
1357                 i = range->start >> PAGE_CACHE_SHIFT;
1358         }
1359         if (!max_to_defrag)
1360                 max_to_defrag = last_index + 1;
1361
1362         /*
1363          * make writeback starts from i, so the defrag range can be
1364          * written sequentially.
1365          */
1366         if (i < inode->i_mapping->writeback_index)
1367                 inode->i_mapping->writeback_index = i;
1368
1369         while (i <= last_index && defrag_count < max_to_defrag &&
1370                (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1371                 PAGE_CACHE_SHIFT)) {
1372                 /*
1373                  * make sure we stop running if someone unmounts
1374                  * the FS
1375                  */
1376                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1377                         break;
1378
1379                 if (btrfs_defrag_cancelled(root->fs_info)) {
1380                         printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1381                         ret = -EAGAIN;
1382                         break;
1383                 }
1384
1385                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1386                                          extent_thresh, &last_len, &skip,
1387                                          &defrag_end, range->flags &
1388                                          BTRFS_DEFRAG_RANGE_COMPRESS)) {
1389                         unsigned long next;
1390                         /*
1391                          * the should_defrag function tells us how much to skip
1392                          * bump our counter by the suggested amount
1393                          */
1394                         next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1395                         i = max(i + 1, next);
1396                         continue;
1397                 }
1398
1399                 if (!newer_than) {
1400                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1401                                    PAGE_CACHE_SHIFT) - i;
1402                         cluster = min(cluster, max_cluster);
1403                 } else {
1404                         cluster = max_cluster;
1405                 }
1406
1407                 if (i + cluster > ra_index) {
1408                         ra_index = max(i, ra_index);
1409                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1410                                        cluster);
1411                         ra_index += max_cluster;
1412                 }
1413
1414                 mutex_lock(&inode->i_mutex);
1415                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1416                         BTRFS_I(inode)->force_compress = compress_type;
1417                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1418                 if (ret < 0) {
1419                         mutex_unlock(&inode->i_mutex);
1420                         goto out_ra;
1421                 }
1422
1423                 defrag_count += ret;
1424                 balance_dirty_pages_ratelimited(inode->i_mapping);
1425                 mutex_unlock(&inode->i_mutex);
1426
1427                 if (newer_than) {
1428                         if (newer_off == (u64)-1)
1429                                 break;
1430
1431                         if (ret > 0)
1432                                 i += ret;
1433
1434                         newer_off = max(newer_off + 1,
1435                                         (u64)i << PAGE_CACHE_SHIFT);
1436
1437                         ret = find_new_extents(root, inode,
1438                                                newer_than, &newer_off,
1439                                                64 * 1024);
1440                         if (!ret) {
1441                                 range->start = newer_off;
1442                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1443                         } else {
1444                                 break;
1445                         }
1446                 } else {
1447                         if (ret > 0) {
1448                                 i += ret;
1449                                 last_len += ret << PAGE_CACHE_SHIFT;
1450                         } else {
1451                                 i++;
1452                                 last_len = 0;
1453                         }
1454                 }
1455         }
1456
1457         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1458                 filemap_flush(inode->i_mapping);
1459                 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1460                              &BTRFS_I(inode)->runtime_flags))
1461                         filemap_flush(inode->i_mapping);
1462         }
1463
1464         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1465                 /* the filemap_flush will queue IO into the worker threads, but
1466                  * we have to make sure the IO is actually started and that
1467                  * ordered extents get created before we return
1468                  */
1469                 atomic_inc(&root->fs_info->async_submit_draining);
1470                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1471                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1472                         wait_event(root->fs_info->async_submit_wait,
1473                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1474                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1475                 }
1476                 atomic_dec(&root->fs_info->async_submit_draining);
1477         }
1478
1479         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1480                 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1481         }
1482
1483         ret = defrag_count;
1484
1485 out_ra:
1486         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1487                 mutex_lock(&inode->i_mutex);
1488                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1489                 mutex_unlock(&inode->i_mutex);
1490         }
1491         if (!file)
1492                 kfree(ra);
1493         kfree(pages);
1494         return ret;
1495 }
1496
1497 static noinline int btrfs_ioctl_resize(struct file *file,
1498                                         void __user *arg)
1499 {
1500         u64 new_size;
1501         u64 old_size;
1502         u64 devid = 1;
1503         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1504         struct btrfs_ioctl_vol_args *vol_args;
1505         struct btrfs_trans_handle *trans;
1506         struct btrfs_device *device = NULL;
1507         char *sizestr;
1508         char *retptr;
1509         char *devstr = NULL;
1510         int ret = 0;
1511         int mod = 0;
1512
1513         if (!capable(CAP_SYS_ADMIN))
1514                 return -EPERM;
1515
1516         ret = mnt_want_write_file(file);
1517         if (ret)
1518                 return ret;
1519
1520         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1521                         1)) {
1522                 mnt_drop_write_file(file);
1523                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1524         }
1525
1526         mutex_lock(&root->fs_info->volume_mutex);
1527         vol_args = memdup_user(arg, sizeof(*vol_args));
1528         if (IS_ERR(vol_args)) {
1529                 ret = PTR_ERR(vol_args);
1530                 goto out;
1531         }
1532
1533         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1534
1535         sizestr = vol_args->name;
1536         devstr = strchr(sizestr, ':');
1537         if (devstr) {
1538                 sizestr = devstr + 1;
1539                 *devstr = '\0';
1540                 devstr = vol_args->name;
1541                 ret = kstrtoull(devstr, 10, &devid);
1542                 if (ret)
1543                         goto out_free;
1544                 if (!devid) {
1545                         ret = -EINVAL;
1546                         goto out_free;
1547                 }
1548                 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1549         }
1550
1551         device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1552         if (!device) {
1553                 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1554                        devid);
1555                 ret = -ENODEV;
1556                 goto out_free;
1557         }
1558
1559         if (!device->writeable) {
1560                 btrfs_info(root->fs_info,
1561                            "resizer unable to apply on readonly device %llu",
1562                        devid);
1563                 ret = -EPERM;
1564                 goto out_free;
1565         }
1566
1567         if (!strcmp(sizestr, "max"))
1568                 new_size = device->bdev->bd_inode->i_size;
1569         else {
1570                 if (sizestr[0] == '-') {
1571                         mod = -1;
1572                         sizestr++;
1573                 } else if (sizestr[0] == '+') {
1574                         mod = 1;
1575                         sizestr++;
1576                 }
1577                 new_size = memparse(sizestr, &retptr);
1578                 if (*retptr != '\0' || new_size == 0) {
1579                         ret = -EINVAL;
1580                         goto out_free;
1581                 }
1582         }
1583
1584         if (device->is_tgtdev_for_dev_replace) {
1585                 ret = -EPERM;
1586                 goto out_free;
1587         }
1588
1589         old_size = device->total_bytes;
1590
1591         if (mod < 0) {
1592                 if (new_size > old_size) {
1593                         ret = -EINVAL;
1594                         goto out_free;
1595                 }
1596                 new_size = old_size - new_size;
1597         } else if (mod > 0) {
1598                 if (new_size > ULLONG_MAX - old_size) {
1599                         ret = -ERANGE;
1600                         goto out_free;
1601                 }
1602                 new_size = old_size + new_size;
1603         }
1604
1605         if (new_size < 256 * 1024 * 1024) {
1606                 ret = -EINVAL;
1607                 goto out_free;
1608         }
1609         if (new_size > device->bdev->bd_inode->i_size) {
1610                 ret = -EFBIG;
1611                 goto out_free;
1612         }
1613
1614         do_div(new_size, root->sectorsize);
1615         new_size *= root->sectorsize;
1616
1617         printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1618                       rcu_str_deref(device->name), new_size);
1619
1620         if (new_size > old_size) {
1621                 trans = btrfs_start_transaction(root, 0);
1622                 if (IS_ERR(trans)) {
1623                         ret = PTR_ERR(trans);
1624                         goto out_free;
1625                 }
1626                 ret = btrfs_grow_device(trans, device, new_size);
1627                 btrfs_commit_transaction(trans, root);
1628         } else if (new_size < old_size) {
1629                 ret = btrfs_shrink_device(device, new_size);
1630         } /* equal, nothing need to do */
1631
1632 out_free:
1633         kfree(vol_args);
1634 out:
1635         mutex_unlock(&root->fs_info->volume_mutex);
1636         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1637         mnt_drop_write_file(file);
1638         return ret;
1639 }
1640
1641 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1642                                 char *name, unsigned long fd, int subvol,
1643                                 u64 *transid, bool readonly,
1644                                 struct btrfs_qgroup_inherit *inherit)
1645 {
1646         int namelen;
1647         int ret = 0;
1648
1649         ret = mnt_want_write_file(file);
1650         if (ret)
1651                 goto out;
1652
1653         namelen = strlen(name);
1654         if (strchr(name, '/')) {
1655                 ret = -EINVAL;
1656                 goto out_drop_write;
1657         }
1658
1659         if (name[0] == '.' &&
1660            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1661                 ret = -EEXIST;
1662                 goto out_drop_write;
1663         }
1664
1665         if (subvol) {
1666                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1667                                      NULL, transid, readonly, inherit);
1668         } else {
1669                 struct fd src = fdget(fd);
1670                 struct inode *src_inode;
1671                 if (!src.file) {
1672                         ret = -EINVAL;
1673                         goto out_drop_write;
1674                 }
1675
1676                 src_inode = file_inode(src.file);
1677                 if (src_inode->i_sb != file_inode(file)->i_sb) {
1678                         btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1679                                    "Snapshot src from another FS");
1680                         ret = -EXDEV;
1681                 } else if (!inode_owner_or_capable(src_inode)) {
1682                         /*
1683                          * Subvolume creation is not restricted, but snapshots
1684                          * are limited to own subvolumes only
1685                          */
1686                         ret = -EPERM;
1687                 } else {
1688                         ret = btrfs_mksubvol(&file->f_path, name, namelen,
1689                                              BTRFS_I(src_inode)->root,
1690                                              transid, readonly, inherit);
1691                 }
1692                 fdput(src);
1693         }
1694 out_drop_write:
1695         mnt_drop_write_file(file);
1696 out:
1697         return ret;
1698 }
1699
1700 static noinline int btrfs_ioctl_snap_create(struct file *file,
1701                                             void __user *arg, int subvol)
1702 {
1703         struct btrfs_ioctl_vol_args *vol_args;
1704         int ret;
1705
1706         vol_args = memdup_user(arg, sizeof(*vol_args));
1707         if (IS_ERR(vol_args))
1708                 return PTR_ERR(vol_args);
1709         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1710
1711         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1712                                               vol_args->fd, subvol,
1713                                               NULL, false, NULL);
1714
1715         kfree(vol_args);
1716         return ret;
1717 }
1718
1719 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1720                                                void __user *arg, int subvol)
1721 {
1722         struct btrfs_ioctl_vol_args_v2 *vol_args;
1723         int ret;
1724         u64 transid = 0;
1725         u64 *ptr = NULL;
1726         bool readonly = false;
1727         struct btrfs_qgroup_inherit *inherit = NULL;
1728
1729         vol_args = memdup_user(arg, sizeof(*vol_args));
1730         if (IS_ERR(vol_args))
1731                 return PTR_ERR(vol_args);
1732         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1733
1734         if (vol_args->flags &
1735             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1736               BTRFS_SUBVOL_QGROUP_INHERIT)) {
1737                 ret = -EOPNOTSUPP;
1738                 goto out;
1739         }
1740
1741         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1742                 ptr = &transid;
1743         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1744                 readonly = true;
1745         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1746                 if (vol_args->size > PAGE_CACHE_SIZE) {
1747                         ret = -EINVAL;
1748                         goto out;
1749                 }
1750                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1751                 if (IS_ERR(inherit)) {
1752                         ret = PTR_ERR(inherit);
1753                         goto out;
1754                 }
1755         }
1756
1757         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1758                                               vol_args->fd, subvol, ptr,
1759                                               readonly, inherit);
1760
1761         if (ret == 0 && ptr &&
1762             copy_to_user(arg +
1763                          offsetof(struct btrfs_ioctl_vol_args_v2,
1764                                   transid), ptr, sizeof(*ptr)))
1765                 ret = -EFAULT;
1766 out:
1767         kfree(vol_args);
1768         kfree(inherit);
1769         return ret;
1770 }
1771
1772 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1773                                                 void __user *arg)
1774 {
1775         struct inode *inode = file_inode(file);
1776         struct btrfs_root *root = BTRFS_I(inode)->root;
1777         int ret = 0;
1778         u64 flags = 0;
1779
1780         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1781                 return -EINVAL;
1782
1783         down_read(&root->fs_info->subvol_sem);
1784         if (btrfs_root_readonly(root))
1785                 flags |= BTRFS_SUBVOL_RDONLY;
1786         up_read(&root->fs_info->subvol_sem);
1787
1788         if (copy_to_user(arg, &flags, sizeof(flags)))
1789                 ret = -EFAULT;
1790
1791         return ret;
1792 }
1793
1794 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1795                                               void __user *arg)
1796 {
1797         struct inode *inode = file_inode(file);
1798         struct btrfs_root *root = BTRFS_I(inode)->root;
1799         struct btrfs_trans_handle *trans;
1800         u64 root_flags;
1801         u64 flags;
1802         int ret = 0;
1803
1804         if (!inode_owner_or_capable(inode))
1805                 return -EPERM;
1806
1807         ret = mnt_want_write_file(file);
1808         if (ret)
1809                 goto out;
1810
1811         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1812                 ret = -EINVAL;
1813                 goto out_drop_write;
1814         }
1815
1816         if (copy_from_user(&flags, arg, sizeof(flags))) {
1817                 ret = -EFAULT;
1818                 goto out_drop_write;
1819         }
1820
1821         if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1822                 ret = -EINVAL;
1823                 goto out_drop_write;
1824         }
1825
1826         if (flags & ~BTRFS_SUBVOL_RDONLY) {
1827                 ret = -EOPNOTSUPP;
1828                 goto out_drop_write;
1829         }
1830
1831         down_write(&root->fs_info->subvol_sem);
1832
1833         /* nothing to do */
1834         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1835                 goto out_drop_sem;
1836
1837         root_flags = btrfs_root_flags(&root->root_item);
1838         if (flags & BTRFS_SUBVOL_RDONLY) {
1839                 btrfs_set_root_flags(&root->root_item,
1840                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1841         } else {
1842                 /*
1843                  * Block RO -> RW transition if this subvolume is involved in
1844                  * send
1845                  */
1846                 spin_lock(&root->root_item_lock);
1847                 if (root->send_in_progress == 0) {
1848                         btrfs_set_root_flags(&root->root_item,
1849                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1850                         spin_unlock(&root->root_item_lock);
1851                 } else {
1852                         spin_unlock(&root->root_item_lock);
1853                         btrfs_warn(root->fs_info,
1854                         "Attempt to set subvolume %llu read-write during send",
1855                                         root->root_key.objectid);
1856                         ret = -EPERM;
1857                         goto out_drop_sem;
1858                 }
1859         }
1860
1861         trans = btrfs_start_transaction(root, 1);
1862         if (IS_ERR(trans)) {
1863                 ret = PTR_ERR(trans);
1864                 goto out_reset;
1865         }
1866
1867         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1868                                 &root->root_key, &root->root_item);
1869
1870         btrfs_commit_transaction(trans, root);
1871 out_reset:
1872         if (ret)
1873                 btrfs_set_root_flags(&root->root_item, root_flags);
1874 out_drop_sem:
1875         up_write(&root->fs_info->subvol_sem);
1876 out_drop_write:
1877         mnt_drop_write_file(file);
1878 out:
1879         return ret;
1880 }
1881
1882 /*
1883  * helper to check if the subvolume references other subvolumes
1884  */
1885 static noinline int may_destroy_subvol(struct btrfs_root *root)
1886 {
1887         struct btrfs_path *path;
1888         struct btrfs_dir_item *di;
1889         struct btrfs_key key;
1890         u64 dir_id;
1891         int ret;
1892
1893         path = btrfs_alloc_path();
1894         if (!path)
1895                 return -ENOMEM;
1896
1897         /* Make sure this root isn't set as the default subvol */
1898         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1899         di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1900                                    dir_id, "default", 7, 0);
1901         if (di && !IS_ERR(di)) {
1902                 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1903                 if (key.objectid == root->root_key.objectid) {
1904                         ret = -EPERM;
1905                         btrfs_err(root->fs_info, "deleting default subvolume "
1906                                   "%llu is not allowed", key.objectid);
1907                         goto out;
1908                 }
1909                 btrfs_release_path(path);
1910         }
1911
1912         key.objectid = root->root_key.objectid;
1913         key.type = BTRFS_ROOT_REF_KEY;
1914         key.offset = (u64)-1;
1915
1916         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1917                                 &key, path, 0, 0);
1918         if (ret < 0)
1919                 goto out;
1920         BUG_ON(ret == 0);
1921
1922         ret = 0;
1923         if (path->slots[0] > 0) {
1924                 path->slots[0]--;
1925                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1926                 if (key.objectid == root->root_key.objectid &&
1927                     key.type == BTRFS_ROOT_REF_KEY)
1928                         ret = -ENOTEMPTY;
1929         }
1930 out:
1931         btrfs_free_path(path);
1932         return ret;
1933 }
1934
1935 static noinline int key_in_sk(struct btrfs_key *key,
1936                               struct btrfs_ioctl_search_key *sk)
1937 {
1938         struct btrfs_key test;
1939         int ret;
1940
1941         test.objectid = sk->min_objectid;
1942         test.type = sk->min_type;
1943         test.offset = sk->min_offset;
1944
1945         ret = btrfs_comp_cpu_keys(key, &test);
1946         if (ret < 0)
1947                 return 0;
1948
1949         test.objectid = sk->max_objectid;
1950         test.type = sk->max_type;
1951         test.offset = sk->max_offset;
1952
1953         ret = btrfs_comp_cpu_keys(key, &test);
1954         if (ret > 0)
1955                 return 0;
1956         return 1;
1957 }
1958
1959 static noinline int copy_to_sk(struct btrfs_root *root,
1960                                struct btrfs_path *path,
1961                                struct btrfs_key *key,
1962                                struct btrfs_ioctl_search_key *sk,
1963                                size_t *buf_size,
1964                                char __user *ubuf,
1965                                unsigned long *sk_offset,
1966                                int *num_found)
1967 {
1968         u64 found_transid;
1969         struct extent_buffer *leaf;
1970         struct btrfs_ioctl_search_header sh;
1971         unsigned long item_off;
1972         unsigned long item_len;
1973         int nritems;
1974         int i;
1975         int slot;
1976         int ret = 0;
1977
1978         leaf = path->nodes[0];
1979         slot = path->slots[0];
1980         nritems = btrfs_header_nritems(leaf);
1981
1982         if (btrfs_header_generation(leaf) > sk->max_transid) {
1983                 i = nritems;
1984                 goto advance_key;
1985         }
1986         found_transid = btrfs_header_generation(leaf);
1987
1988         for (i = slot; i < nritems; i++) {
1989                 item_off = btrfs_item_ptr_offset(leaf, i);
1990                 item_len = btrfs_item_size_nr(leaf, i);
1991
1992                 btrfs_item_key_to_cpu(leaf, key, i);
1993                 if (!key_in_sk(key, sk))
1994                         continue;
1995
1996                 if (sizeof(sh) + item_len > *buf_size) {
1997                         if (*num_found) {
1998                                 ret = 1;
1999                                 goto out;
2000                         }
2001
2002                         /*
2003                          * return one empty item back for v1, which does not
2004                          * handle -EOVERFLOW
2005                          */
2006
2007                         *buf_size = sizeof(sh) + item_len;
2008                         item_len = 0;
2009                         ret = -EOVERFLOW;
2010                 }
2011
2012                 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2013                         ret = 1;
2014                         goto out;
2015                 }
2016
2017                 sh.objectid = key->objectid;
2018                 sh.offset = key->offset;
2019                 sh.type = key->type;
2020                 sh.len = item_len;
2021                 sh.transid = found_transid;
2022
2023                 /* copy search result header */
2024                 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2025                         ret = -EFAULT;
2026                         goto out;
2027                 }
2028
2029                 *sk_offset += sizeof(sh);
2030
2031                 if (item_len) {
2032                         char __user *up = ubuf + *sk_offset;
2033                         /* copy the item */
2034                         if (read_extent_buffer_to_user(leaf, up,
2035                                                        item_off, item_len)) {
2036                                 ret = -EFAULT;
2037                                 goto out;
2038                         }
2039
2040                         *sk_offset += item_len;
2041                 }
2042                 (*num_found)++;
2043
2044                 if (ret) /* -EOVERFLOW from above */
2045                         goto out;
2046
2047                 if (*num_found >= sk->nr_items) {
2048                         ret = 1;
2049                         goto out;
2050                 }
2051         }
2052 advance_key:
2053         ret = 0;
2054         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2055                 key->offset++;
2056         else if (key->type < (u8)-1 && key->type < sk->max_type) {
2057                 key->offset = 0;
2058                 key->type++;
2059         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2060                 key->offset = 0;
2061                 key->type = 0;
2062                 key->objectid++;
2063         } else
2064                 ret = 1;
2065 out:
2066         /*
2067          *  0: all items from this leaf copied, continue with next
2068          *  1: * more items can be copied, but unused buffer is too small
2069          *     * all items were found
2070          *     Either way, it will stops the loop which iterates to the next
2071          *     leaf
2072          *  -EOVERFLOW: item was to large for buffer
2073          *  -EFAULT: could not copy extent buffer back to userspace
2074          */
2075         return ret;
2076 }
2077
2078 static noinline int search_ioctl(struct inode *inode,
2079                                  struct btrfs_ioctl_search_key *sk,
2080                                  size_t *buf_size,
2081                                  char __user *ubuf)
2082 {
2083         struct btrfs_root *root;
2084         struct btrfs_key key;
2085         struct btrfs_path *path;
2086         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2087         int ret;
2088         int num_found = 0;
2089         unsigned long sk_offset = 0;
2090
2091         if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2092                 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2093                 return -EOVERFLOW;
2094         }
2095
2096         path = btrfs_alloc_path();
2097         if (!path)
2098                 return -ENOMEM;
2099
2100         if (sk->tree_id == 0) {
2101                 /* search the root of the inode that was passed */
2102                 root = BTRFS_I(inode)->root;
2103         } else {
2104                 key.objectid = sk->tree_id;
2105                 key.type = BTRFS_ROOT_ITEM_KEY;
2106                 key.offset = (u64)-1;
2107                 root = btrfs_read_fs_root_no_name(info, &key);
2108                 if (IS_ERR(root)) {
2109                         printk(KERN_ERR "BTRFS: could not find root %llu\n",
2110                                sk->tree_id);
2111                         btrfs_free_path(path);
2112                         return -ENOENT;
2113                 }
2114         }
2115
2116         key.objectid = sk->min_objectid;
2117         key.type = sk->min_type;
2118         key.offset = sk->min_offset;
2119
2120         path->keep_locks = 1;
2121
2122         while (1) {
2123                 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2124                 if (ret != 0) {
2125                         if (ret > 0)
2126                                 ret = 0;
2127                         goto err;
2128                 }
2129                 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2130                                  &sk_offset, &num_found);
2131                 btrfs_release_path(path);
2132                 if (ret)
2133                         break;
2134
2135         }
2136         if (ret > 0)
2137                 ret = 0;
2138 err:
2139         sk->nr_items = num_found;
2140         btrfs_free_path(path);
2141         return ret;
2142 }
2143
2144 static noinline int btrfs_ioctl_tree_search(struct file *file,
2145                                            void __user *argp)
2146 {
2147         struct btrfs_ioctl_search_args __user *uargs;
2148         struct btrfs_ioctl_search_key sk;
2149         struct inode *inode;
2150         int ret;
2151         size_t buf_size;
2152
2153         if (!capable(CAP_SYS_ADMIN))
2154                 return -EPERM;
2155
2156         uargs = (struct btrfs_ioctl_search_args __user *)argp;
2157
2158         if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2159                 return -EFAULT;
2160
2161         buf_size = sizeof(uargs->buf);
2162
2163         inode = file_inode(file);
2164         ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2165
2166         /*
2167          * In the origin implementation an overflow is handled by returning a
2168          * search header with a len of zero, so reset ret.
2169          */
2170         if (ret == -EOVERFLOW)
2171                 ret = 0;
2172
2173         if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2174                 ret = -EFAULT;
2175         return ret;
2176 }
2177
2178 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2179                                                void __user *argp)
2180 {
2181         struct btrfs_ioctl_search_args_v2 __user *uarg;
2182         struct btrfs_ioctl_search_args_v2 args;
2183         struct inode *inode;
2184         int ret;
2185         size_t buf_size;
2186         const size_t buf_limit = 16 * 1024 * 1024;
2187
2188         if (!capable(CAP_SYS_ADMIN))
2189                 return -EPERM;
2190
2191         /* copy search header and buffer size */
2192         uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2193         if (copy_from_user(&args, uarg, sizeof(args)))
2194                 return -EFAULT;
2195
2196         buf_size = args.buf_size;
2197
2198         if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2199                 return -EOVERFLOW;
2200
2201         /* limit result size to 16MB */
2202         if (buf_size > buf_limit)
2203                 buf_size = buf_limit;
2204
2205         inode = file_inode(file);
2206         ret = search_ioctl(inode, &args.key, &buf_size,
2207                            (char *)(&uarg->buf[0]));
2208         if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2209                 ret = -EFAULT;
2210         else if (ret == -EOVERFLOW &&
2211                 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2212                 ret = -EFAULT;
2213
2214         return ret;
2215 }
2216
2217 /*
2218  * Search INODE_REFs to identify path name of 'dirid' directory
2219  * in a 'tree_id' tree. and sets path name to 'name'.
2220  */
2221 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2222                                 u64 tree_id, u64 dirid, char *name)
2223 {
2224         struct btrfs_root *root;
2225         struct btrfs_key key;
2226         char *ptr;
2227         int ret = -1;
2228         int slot;
2229         int len;
2230         int total_len = 0;
2231         struct btrfs_inode_ref *iref;
2232         struct extent_buffer *l;
2233         struct btrfs_path *path;
2234
2235         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2236                 name[0]='\0';
2237                 return 0;
2238         }
2239
2240         path = btrfs_alloc_path();
2241         if (!path)
2242                 return -ENOMEM;
2243
2244         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2245
2246         key.objectid = tree_id;
2247         key.type = BTRFS_ROOT_ITEM_KEY;
2248         key.offset = (u64)-1;
2249         root = btrfs_read_fs_root_no_name(info, &key);
2250         if (IS_ERR(root)) {
2251                 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2252                 ret = -ENOENT;
2253                 goto out;
2254         }
2255
2256         key.objectid = dirid;
2257         key.type = BTRFS_INODE_REF_KEY;
2258         key.offset = (u64)-1;
2259
2260         while (1) {
2261                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2262                 if (ret < 0)
2263                         goto out;
2264                 else if (ret > 0) {
2265                         ret = btrfs_previous_item(root, path, dirid,
2266                                                   BTRFS_INODE_REF_KEY);
2267                         if (ret < 0)
2268                                 goto out;
2269                         else if (ret > 0) {
2270                                 ret = -ENOENT;
2271                                 goto out;
2272                         }
2273                 }
2274
2275                 l = path->nodes[0];
2276                 slot = path->slots[0];
2277                 btrfs_item_key_to_cpu(l, &key, slot);
2278
2279                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2280                 len = btrfs_inode_ref_name_len(l, iref);
2281                 ptr -= len + 1;
2282                 total_len += len + 1;
2283                 if (ptr < name) {
2284                         ret = -ENAMETOOLONG;
2285                         goto out;
2286                 }
2287
2288                 *(ptr + len) = '/';
2289                 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2290
2291                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2292                         break;
2293
2294                 btrfs_release_path(path);
2295                 key.objectid = key.offset;
2296                 key.offset = (u64)-1;
2297                 dirid = key.objectid;
2298         }
2299         memmove(name, ptr, total_len);
2300         name[total_len] = '\0';
2301         ret = 0;
2302 out:
2303         btrfs_free_path(path);
2304         return ret;
2305 }
2306
2307 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2308                                            void __user *argp)
2309 {
2310          struct btrfs_ioctl_ino_lookup_args *args;
2311          struct inode *inode;
2312          int ret;
2313
2314         if (!capable(CAP_SYS_ADMIN))
2315                 return -EPERM;
2316
2317         args = memdup_user(argp, sizeof(*args));
2318         if (IS_ERR(args))
2319                 return PTR_ERR(args);
2320
2321         inode = file_inode(file);
2322
2323         if (args->treeid == 0)
2324                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2325
2326         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2327                                         args->treeid, args->objectid,
2328                                         args->name);
2329
2330         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2331                 ret = -EFAULT;
2332
2333         kfree(args);
2334         return ret;
2335 }
2336
2337 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2338                                              void __user *arg)
2339 {
2340         struct dentry *parent = file->f_path.dentry;
2341         struct dentry *dentry;
2342         struct inode *dir = parent->d_inode;
2343         struct inode *inode;
2344         struct btrfs_root *root = BTRFS_I(dir)->root;
2345         struct btrfs_root *dest = NULL;
2346         struct btrfs_ioctl_vol_args *vol_args;
2347         struct btrfs_trans_handle *trans;
2348         struct btrfs_block_rsv block_rsv;
2349         u64 root_flags;
2350         u64 qgroup_reserved;
2351         int namelen;
2352         int ret;
2353         int err = 0;
2354
2355         vol_args = memdup_user(arg, sizeof(*vol_args));
2356         if (IS_ERR(vol_args))
2357                 return PTR_ERR(vol_args);
2358
2359         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2360         namelen = strlen(vol_args->name);
2361         if (strchr(vol_args->name, '/') ||
2362             strncmp(vol_args->name, "..", namelen) == 0) {
2363                 err = -EINVAL;
2364                 goto out;
2365         }
2366
2367         err = mnt_want_write_file(file);
2368         if (err)
2369                 goto out;
2370
2371
2372         err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2373         if (err == -EINTR)
2374                 goto out_drop_write;
2375         dentry = lookup_one_len(vol_args->name, parent, namelen);
2376         if (IS_ERR(dentry)) {
2377                 err = PTR_ERR(dentry);
2378                 goto out_unlock_dir;
2379         }
2380
2381         if (!dentry->d_inode) {
2382                 err = -ENOENT;
2383                 goto out_dput;
2384         }
2385
2386         inode = dentry->d_inode;
2387         dest = BTRFS_I(inode)->root;
2388         if (!capable(CAP_SYS_ADMIN)) {
2389                 /*
2390                  * Regular user.  Only allow this with a special mount
2391                  * option, when the user has write+exec access to the
2392                  * subvol root, and when rmdir(2) would have been
2393                  * allowed.
2394                  *
2395                  * Note that this is _not_ check that the subvol is
2396                  * empty or doesn't contain data that we wouldn't
2397                  * otherwise be able to delete.
2398                  *
2399                  * Users who want to delete empty subvols should try
2400                  * rmdir(2).
2401                  */
2402                 err = -EPERM;
2403                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2404                         goto out_dput;
2405
2406                 /*
2407                  * Do not allow deletion if the parent dir is the same
2408                  * as the dir to be deleted.  That means the ioctl
2409                  * must be called on the dentry referencing the root
2410                  * of the subvol, not a random directory contained
2411                  * within it.
2412                  */
2413                 err = -EINVAL;
2414                 if (root == dest)
2415                         goto out_dput;
2416
2417                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2418                 if (err)
2419                         goto out_dput;
2420         }
2421
2422         /* check if subvolume may be deleted by a user */
2423         err = btrfs_may_delete(dir, dentry, 1);
2424         if (err)
2425                 goto out_dput;
2426
2427         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2428                 err = -EINVAL;
2429                 goto out_dput;
2430         }
2431
2432         mutex_lock(&inode->i_mutex);
2433
2434         /*
2435          * Don't allow to delete a subvolume with send in progress. This is
2436          * inside the i_mutex so the error handling that has to drop the bit
2437          * again is not run concurrently.
2438          */
2439         spin_lock(&dest->root_item_lock);
2440         root_flags = btrfs_root_flags(&dest->root_item);
2441         if (dest->send_in_progress == 0) {
2442                 btrfs_set_root_flags(&dest->root_item,
2443                                 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2444                 spin_unlock(&dest->root_item_lock);
2445         } else {
2446                 spin_unlock(&dest->root_item_lock);
2447                 btrfs_warn(root->fs_info,
2448                         "Attempt to delete subvolume %llu during send",
2449                         dest->root_key.objectid);
2450                 err = -EPERM;
2451                 goto out_dput;
2452         }
2453
2454         err = d_invalidate(dentry);
2455         if (err)
2456                 goto out_unlock;
2457
2458         down_write(&root->fs_info->subvol_sem);
2459
2460         err = may_destroy_subvol(dest);
2461         if (err)
2462                 goto out_up_write;
2463
2464         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2465         /*
2466          * One for dir inode, two for dir entries, two for root
2467          * ref/backref.
2468          */
2469         err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2470                                                5, &qgroup_reserved, true);
2471         if (err)
2472                 goto out_up_write;
2473
2474         trans = btrfs_start_transaction(root, 0);
2475         if (IS_ERR(trans)) {
2476                 err = PTR_ERR(trans);
2477                 goto out_release;
2478         }
2479         trans->block_rsv = &block_rsv;
2480         trans->bytes_reserved = block_rsv.size;
2481
2482         ret = btrfs_unlink_subvol(trans, root, dir,
2483                                 dest->root_key.objectid,
2484                                 dentry->d_name.name,
2485                                 dentry->d_name.len);
2486         if (ret) {
2487                 err = ret;
2488                 btrfs_abort_transaction(trans, root, ret);
2489                 goto out_end_trans;
2490         }
2491
2492         btrfs_record_root_in_trans(trans, dest);
2493
2494         memset(&dest->root_item.drop_progress, 0,
2495                 sizeof(dest->root_item.drop_progress));
2496         dest->root_item.drop_level = 0;
2497         btrfs_set_root_refs(&dest->root_item, 0);
2498
2499         if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2500                 ret = btrfs_insert_orphan_item(trans,
2501                                         root->fs_info->tree_root,
2502                                         dest->root_key.objectid);
2503                 if (ret) {
2504                         btrfs_abort_transaction(trans, root, ret);
2505                         err = ret;
2506                         goto out_end_trans;
2507                 }
2508         }
2509
2510         ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2511                                   dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2512                                   dest->root_key.objectid);
2513         if (ret && ret != -ENOENT) {
2514                 btrfs_abort_transaction(trans, root, ret);
2515                 err = ret;
2516                 goto out_end_trans;
2517         }
2518         if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2519                 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2520                                           dest->root_item.received_uuid,
2521                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2522                                           dest->root_key.objectid);
2523                 if (ret && ret != -ENOENT) {
2524                         btrfs_abort_transaction(trans, root, ret);
2525                         err = ret;
2526                         goto out_end_trans;
2527                 }
2528         }
2529
2530 out_end_trans:
2531         trans->block_rsv = NULL;
2532         trans->bytes_reserved = 0;
2533         ret = btrfs_end_transaction(trans, root);
2534         if (ret && !err)
2535                 err = ret;
2536         inode->i_flags |= S_DEAD;
2537 out_release:
2538         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2539 out_up_write:
2540         up_write(&root->fs_info->subvol_sem);
2541 out_unlock:
2542         if (err) {
2543                 spin_lock(&dest->root_item_lock);
2544                 root_flags = btrfs_root_flags(&dest->root_item);
2545                 btrfs_set_root_flags(&dest->root_item,
2546                                 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2547                 spin_unlock(&dest->root_item_lock);
2548         }
2549         mutex_unlock(&inode->i_mutex);
2550         if (!err) {
2551                 shrink_dcache_sb(root->fs_info->sb);
2552                 btrfs_invalidate_inodes(dest);
2553                 d_delete(dentry);
2554                 ASSERT(dest->send_in_progress == 0);
2555
2556                 /* the last ref */
2557                 if (dest->cache_inode) {
2558                         iput(dest->cache_inode);
2559                         dest->cache_inode = NULL;
2560                 }
2561         }
2562 out_dput:
2563         dput(dentry);
2564 out_unlock_dir:
2565         mutex_unlock(&dir->i_mutex);
2566 out_drop_write:
2567         mnt_drop_write_file(file);
2568 out:
2569         kfree(vol_args);
2570         return err;
2571 }
2572
2573 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2574 {
2575         struct inode *inode = file_inode(file);
2576         struct btrfs_root *root = BTRFS_I(inode)->root;
2577         struct btrfs_ioctl_defrag_range_args *range;
2578         int ret;
2579
2580         ret = mnt_want_write_file(file);
2581         if (ret)
2582                 return ret;
2583
2584         if (btrfs_root_readonly(root)) {
2585                 ret = -EROFS;
2586                 goto out;
2587         }
2588
2589         switch (inode->i_mode & S_IFMT) {
2590         case S_IFDIR:
2591                 if (!capable(CAP_SYS_ADMIN)) {
2592                         ret = -EPERM;
2593                         goto out;
2594                 }
2595                 ret = btrfs_defrag_root(root);
2596                 if (ret)
2597                         goto out;
2598                 ret = btrfs_defrag_root(root->fs_info->extent_root);
2599                 break;
2600         case S_IFREG:
2601                 if (!(file->f_mode & FMODE_WRITE)) {
2602                         ret = -EINVAL;
2603                         goto out;
2604                 }
2605
2606                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2607                 if (!range) {
2608                         ret = -ENOMEM;
2609                         goto out;
2610                 }
2611
2612                 if (argp) {
2613                         if (copy_from_user(range, argp,
2614                                            sizeof(*range))) {
2615                                 ret = -EFAULT;
2616                                 kfree(range);
2617                                 goto out;
2618                         }
2619                         /* compression requires us to start the IO */
2620                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2621                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2622                                 range->extent_thresh = (u32)-1;
2623                         }
2624                 } else {
2625                         /* the rest are all set to zero by kzalloc */
2626                         range->len = (u64)-1;
2627                 }
2628                 ret = btrfs_defrag_file(file_inode(file), file,
2629                                         range, 0, 0);
2630                 if (ret > 0)
2631                         ret = 0;
2632                 kfree(range);
2633                 break;
2634         default:
2635                 ret = -EINVAL;
2636         }
2637 out:
2638         mnt_drop_write_file(file);
2639         return ret;
2640 }
2641
2642 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2643 {
2644         struct btrfs_ioctl_vol_args *vol_args;
2645         int ret;
2646
2647         if (!capable(CAP_SYS_ADMIN))
2648                 return -EPERM;
2649
2650         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2651                         1)) {
2652                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2653         }
2654
2655         mutex_lock(&root->fs_info->volume_mutex);
2656         vol_args = memdup_user(arg, sizeof(*vol_args));
2657         if (IS_ERR(vol_args)) {
2658                 ret = PTR_ERR(vol_args);
2659                 goto out;
2660         }
2661
2662         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2663         ret = btrfs_init_new_device(root, vol_args->name);
2664
2665         kfree(vol_args);
2666 out:
2667         mutex_unlock(&root->fs_info->volume_mutex);
2668         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2669         return ret;
2670 }
2671
2672 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2673 {
2674         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2675         struct btrfs_ioctl_vol_args *vol_args;
2676         int ret;
2677
2678         if (!capable(CAP_SYS_ADMIN))
2679                 return -EPERM;
2680
2681         ret = mnt_want_write_file(file);
2682         if (ret)
2683                 return ret;
2684
2685         vol_args = memdup_user(arg, sizeof(*vol_args));
2686         if (IS_ERR(vol_args)) {
2687                 ret = PTR_ERR(vol_args);
2688                 goto out;
2689         }
2690
2691         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2692
2693         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2694                         1)) {
2695                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2696                 goto out;
2697         }
2698
2699         mutex_lock(&root->fs_info->volume_mutex);
2700         ret = btrfs_rm_device(root, vol_args->name);
2701         mutex_unlock(&root->fs_info->volume_mutex);
2702         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2703
2704 out:
2705         kfree(vol_args);
2706         mnt_drop_write_file(file);
2707         return ret;
2708 }
2709
2710 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2711 {
2712         struct btrfs_ioctl_fs_info_args *fi_args;
2713         struct btrfs_device *device;
2714         struct btrfs_device *next;
2715         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2716         int ret = 0;
2717
2718         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2719         if (!fi_args)
2720                 return -ENOMEM;
2721
2722         mutex_lock(&fs_devices->device_list_mutex);
2723         fi_args->num_devices = fs_devices->num_devices;
2724         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2725
2726         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2727                 if (device->devid > fi_args->max_id)
2728                         fi_args->max_id = device->devid;
2729         }
2730         mutex_unlock(&fs_devices->device_list_mutex);
2731
2732         fi_args->nodesize = root->fs_info->super_copy->nodesize;
2733         fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2734         fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2735
2736         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2737                 ret = -EFAULT;
2738
2739         kfree(fi_args);
2740         return ret;
2741 }
2742
2743 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2744 {
2745         struct btrfs_ioctl_dev_info_args *di_args;
2746         struct btrfs_device *dev;
2747         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2748         int ret = 0;
2749         char *s_uuid = NULL;
2750
2751         di_args = memdup_user(arg, sizeof(*di_args));
2752         if (IS_ERR(di_args))
2753                 return PTR_ERR(di_args);
2754
2755         if (!btrfs_is_empty_uuid(di_args->uuid))
2756                 s_uuid = di_args->uuid;
2757
2758         mutex_lock(&fs_devices->device_list_mutex);
2759         dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2760
2761         if (!dev) {
2762                 ret = -ENODEV;
2763                 goto out;
2764         }
2765
2766         di_args->devid = dev->devid;
2767         di_args->bytes_used = dev->bytes_used;
2768         di_args->total_bytes = dev->total_bytes;
2769         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2770         if (dev->name) {
2771                 struct rcu_string *name;
2772
2773                 rcu_read_lock();
2774                 name = rcu_dereference(dev->name);
2775                 strncpy(di_args->path, name->str, sizeof(di_args->path));
2776                 rcu_read_unlock();
2777                 di_args->path[sizeof(di_args->path) - 1] = 0;
2778         } else {
2779                 di_args->path[0] = '\0';
2780         }
2781
2782 out:
2783         mutex_unlock(&fs_devices->device_list_mutex);
2784         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2785                 ret = -EFAULT;
2786
2787         kfree(di_args);
2788         return ret;
2789 }
2790
2791 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2792 {
2793         struct page *page;
2794         pgoff_t index;
2795         struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2796
2797         index = off >> PAGE_CACHE_SHIFT;
2798
2799         page = grab_cache_page(inode->i_mapping, index);
2800         if (!page)
2801                 return NULL;
2802
2803         if (!PageUptodate(page)) {
2804                 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2805                                                  0))
2806                         return NULL;
2807                 lock_page(page);
2808                 if (!PageUptodate(page)) {
2809                         unlock_page(page);
2810                         page_cache_release(page);
2811                         return NULL;
2812                 }
2813         }
2814         unlock_page(page);
2815
2816         return page;
2817 }
2818
2819 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2820 {
2821         /* do any pending delalloc/csum calc on src, one way or
2822            another, and lock file content */
2823         while (1) {
2824                 struct btrfs_ordered_extent *ordered;
2825                 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2826                 ordered = btrfs_lookup_first_ordered_extent(inode,
2827                                                             off + len - 1);
2828                 if ((!ordered ||
2829                      ordered->file_offset + ordered->len <= off ||
2830                      ordered->file_offset >= off + len) &&
2831                     !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2832                                     off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2833                         if (ordered)
2834                                 btrfs_put_ordered_extent(ordered);
2835                         break;
2836                 }
2837                 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2838                 if (ordered)
2839                         btrfs_put_ordered_extent(ordered);
2840                 btrfs_wait_ordered_range(inode, off, len);
2841         }
2842 }
2843
2844 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2845                                 struct inode *inode2, u64 loff2, u64 len)
2846 {
2847         unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2848         unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2849
2850         mutex_unlock(&inode1->i_mutex);
2851         mutex_unlock(&inode2->i_mutex);
2852 }
2853
2854 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2855                               struct inode *inode2, u64 loff2, u64 len)
2856 {
2857         if (inode1 < inode2) {
2858                 swap(inode1, inode2);
2859                 swap(loff1, loff2);
2860         }
2861
2862         mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2863         lock_extent_range(inode1, loff1, len);
2864         if (inode1 != inode2) {
2865                 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2866                 lock_extent_range(inode2, loff2, len);
2867         }
2868 }
2869
2870 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2871                           u64 dst_loff, u64 len)
2872 {
2873         int ret = 0;
2874         struct page *src_page, *dst_page;
2875         unsigned int cmp_len = PAGE_CACHE_SIZE;
2876         void *addr, *dst_addr;
2877
2878         while (len) {
2879                 if (len < PAGE_CACHE_SIZE)
2880                         cmp_len = len;
2881
2882                 src_page = extent_same_get_page(src, loff);
2883                 if (!src_page)
2884                         return -EINVAL;
2885                 dst_page = extent_same_get_page(dst, dst_loff);
2886                 if (!dst_page) {
2887                         page_cache_release(src_page);
2888                         return -EINVAL;
2889                 }
2890                 addr = kmap_atomic(src_page);
2891                 dst_addr = kmap_atomic(dst_page);
2892
2893                 flush_dcache_page(src_page);
2894                 flush_dcache_page(dst_page);
2895
2896                 if (memcmp(addr, dst_addr, cmp_len))
2897                         ret = BTRFS_SAME_DATA_DIFFERS;
2898
2899                 kunmap_atomic(addr);
2900                 kunmap_atomic(dst_addr);
2901                 page_cache_release(src_page);
2902                 page_cache_release(dst_page);
2903
2904                 if (ret)
2905                         break;
2906
2907                 loff += cmp_len;
2908                 dst_loff += cmp_len;
2909                 len -= cmp_len;
2910         }
2911
2912         return ret;
2913 }
2914
2915 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2916 {
2917         u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2918
2919         if (off + len > inode->i_size || off + len < off)
2920                 return -EINVAL;
2921         /* Check that we are block aligned - btrfs_clone() requires this */
2922         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2923                 return -EINVAL;
2924
2925         return 0;
2926 }
2927
2928 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2929                              struct inode *dst, u64 dst_loff)
2930 {
2931         int ret;
2932
2933         /*
2934          * btrfs_clone() can't handle extents in the same file
2935          * yet. Once that works, we can drop this check and replace it
2936          * with a check for the same inode, but overlapping extents.
2937          */
2938         if (src == dst)
2939                 return -EINVAL;
2940
2941         btrfs_double_lock(src, loff, dst, dst_loff, len);
2942
2943         ret = extent_same_check_offsets(src, loff, len);
2944         if (ret)
2945                 goto out_unlock;
2946
2947         ret = extent_same_check_offsets(dst, dst_loff, len);
2948         if (ret)
2949                 goto out_unlock;
2950
2951         /* don't make the dst file partly checksummed */
2952         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2953             (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2954                 ret = -EINVAL;
2955                 goto out_unlock;
2956         }
2957
2958         ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2959         if (ret == 0)
2960                 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2961
2962 out_unlock:
2963         btrfs_double_unlock(src, loff, dst, dst_loff, len);
2964
2965         return ret;
2966 }
2967
2968 #define BTRFS_MAX_DEDUPE_LEN    (16 * 1024 * 1024)
2969
2970 static long btrfs_ioctl_file_extent_same(struct file *file,
2971                         struct btrfs_ioctl_same_args __user *argp)
2972 {
2973         struct btrfs_ioctl_same_args *same;
2974         struct btrfs_ioctl_same_extent_info *info;
2975         struct inode *src = file_inode(file);
2976         u64 off;
2977         u64 len;
2978         int i;
2979         int ret;
2980         unsigned long size;
2981         u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2982         bool is_admin = capable(CAP_SYS_ADMIN);
2983         u16 count;
2984
2985         if (!(file->f_mode & FMODE_READ))
2986                 return -EINVAL;
2987
2988         ret = mnt_want_write_file(file);
2989         if (ret)
2990                 return ret;
2991
2992         if (get_user(count, &argp->dest_count)) {
2993                 ret = -EFAULT;
2994                 goto out;
2995         }
2996
2997         size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2998
2999         same = memdup_user(argp, size);
3000
3001         if (IS_ERR(same)) {
3002                 ret = PTR_ERR(same);
3003                 goto out;
3004         }
3005
3006         off = same->logical_offset;
3007         len = same->length;
3008
3009         /*
3010          * Limit the total length we will dedupe for each operation.
3011          * This is intended to bound the total time spent in this
3012          * ioctl to something sane.
3013          */
3014         if (len > BTRFS_MAX_DEDUPE_LEN)
3015                 len = BTRFS_MAX_DEDUPE_LEN;
3016
3017         if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
3018                 /*
3019                  * Btrfs does not support blocksize < page_size. As a
3020                  * result, btrfs_cmp_data() won't correctly handle
3021                  * this situation without an update.
3022                  */
3023                 ret = -EINVAL;
3024                 goto out;
3025         }
3026
3027         ret = -EISDIR;
3028         if (S_ISDIR(src->i_mode))
3029                 goto out;
3030
3031         ret = -EACCES;
3032         if (!S_ISREG(src->i_mode))
3033                 goto out;
3034
3035         /* pre-format output fields to sane values */
3036         for (i = 0; i < count; i++) {
3037                 same->info[i].bytes_deduped = 0ULL;
3038                 same->info[i].status = 0;
3039         }
3040
3041         for (i = 0, info = same->info; i < count; i++, info++) {
3042                 struct inode *dst;
3043                 struct fd dst_file = fdget(info->fd);
3044                 if (!dst_file.file) {
3045                         info->status = -EBADF;
3046                         continue;
3047                 }
3048                 dst = file_inode(dst_file.file);
3049
3050                 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3051                         info->status = -EINVAL;
3052                 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3053                         info->status = -EXDEV;
3054                 } else if (S_ISDIR(dst->i_mode)) {
3055                         info->status = -EISDIR;
3056                 } else if (!S_ISREG(dst->i_mode)) {
3057                         info->status = -EACCES;
3058                 } else {
3059                         info->status = btrfs_extent_same(src, off, len, dst,
3060                                                         info->logical_offset);
3061                         if (info->status == 0)
3062                                 info->bytes_deduped += len;
3063                 }
3064                 fdput(dst_file);
3065         }
3066
3067         ret = copy_to_user(argp, same, size);
3068         if (ret)
3069                 ret = -EFAULT;
3070
3071 out:
3072         mnt_drop_write_file(file);
3073         return ret;
3074 }
3075
3076 /* Helper to check and see if this root currently has a ref on the given disk
3077  * bytenr.  If it does then we need to update the quota for this root.  This
3078  * doesn't do anything if quotas aren't enabled.
3079  */
3080 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3081                      u64 disko)
3082 {
3083         struct seq_list tree_mod_seq_elem = {};
3084         struct ulist *roots;
3085         struct ulist_iterator uiter;
3086         struct ulist_node *root_node = NULL;
3087         int ret;
3088
3089         if (!root->fs_info->quota_enabled)
3090                 return 1;
3091
3092         btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3093         ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3094                                    tree_mod_seq_elem.seq, &roots);
3095         if (ret < 0)
3096                 goto out;
3097         ret = 0;
3098         ULIST_ITER_INIT(&uiter);
3099         while ((root_node = ulist_next(roots, &uiter))) {
3100                 if (root_node->val == root->objectid) {
3101                         ret = 1;
3102                         break;
3103                 }
3104         }
3105         ulist_free(roots);
3106 out:
3107         btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3108         return ret;
3109 }
3110
3111 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3112                                      struct inode *inode,
3113                                      u64 endoff,
3114                                      const u64 destoff,
3115                                      const u64 olen)
3116 {
3117         struct btrfs_root *root = BTRFS_I(inode)->root;
3118         int ret;
3119
3120         inode_inc_iversion(inode);
3121         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3122         /*
3123          * We round up to the block size at eof when determining which
3124          * extents to clone above, but shouldn't round up the file size.
3125          */
3126         if (endoff > destoff + olen)
3127                 endoff = destoff + olen;
3128         if (endoff > inode->i_size)
3129                 btrfs_i_size_write(inode, endoff);
3130
3131         ret = btrfs_update_inode(trans, root, inode);
3132         if (ret) {
3133                 btrfs_abort_transaction(trans, root, ret);
3134                 btrfs_end_transaction(trans, root);
3135                 goto out;
3136         }
3137         ret = btrfs_end_transaction(trans, root);
3138 out:
3139         return ret;
3140 }
3141
3142 static void clone_update_extent_map(struct inode *inode,
3143                                     const struct btrfs_trans_handle *trans,
3144                                     const struct btrfs_path *path,
3145                                     const u64 hole_offset,
3146                                     const u64 hole_len)
3147 {
3148         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3149         struct extent_map *em;
3150         int ret;
3151
3152         em = alloc_extent_map();
3153         if (!em) {
3154                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3155                         &BTRFS_I(inode)->runtime_flags);
3156                 return;
3157         }
3158
3159         if (path) {
3160                 struct btrfs_file_extent_item *fi;
3161
3162                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3163                                     struct btrfs_file_extent_item);
3164                 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3165                 em->generation = -1;
3166                 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3167                     BTRFS_FILE_EXTENT_INLINE)
3168                         set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3169                                 &BTRFS_I(inode)->runtime_flags);
3170         } else {
3171                 em->start = hole_offset;
3172                 em->len = hole_len;
3173                 em->ram_bytes = em->len;
3174                 em->orig_start = hole_offset;
3175                 em->block_start = EXTENT_MAP_HOLE;
3176                 em->block_len = 0;
3177                 em->orig_block_len = 0;
3178                 em->compress_type = BTRFS_COMPRESS_NONE;
3179                 em->generation = trans->transid;
3180         }
3181
3182         while (1) {
3183                 write_lock(&em_tree->lock);
3184                 ret = add_extent_mapping(em_tree, em, 1);
3185                 write_unlock(&em_tree->lock);
3186                 if (ret != -EEXIST) {
3187                         free_extent_map(em);
3188                         break;
3189                 }
3190                 btrfs_drop_extent_cache(inode, em->start,
3191                                         em->start + em->len - 1, 0);
3192         }
3193
3194         if (unlikely(ret))
3195                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3196                         &BTRFS_I(inode)->runtime_flags);
3197 }
3198
3199 /**
3200  * btrfs_clone() - clone a range from inode file to another
3201  *
3202  * @src: Inode to clone from
3203  * @inode: Inode to clone to
3204  * @off: Offset within source to start clone from
3205  * @olen: Original length, passed by user, of range to clone
3206  * @olen_aligned: Block-aligned value of olen, extent_same uses
3207  *               identical values here
3208  * @destoff: Offset within @inode to start clone
3209  */
3210 static int btrfs_clone(struct inode *src, struct inode *inode,
3211                        const u64 off, const u64 olen, const u64 olen_aligned,
3212                        const u64 destoff)
3213 {
3214         struct btrfs_root *root = BTRFS_I(inode)->root;
3215         struct btrfs_path *path = NULL;
3216         struct extent_buffer *leaf;
3217         struct btrfs_trans_handle *trans;
3218         char *buf = NULL;
3219         struct btrfs_key key;
3220         u32 nritems;
3221         int slot;
3222         int ret;
3223         int no_quota;
3224         const u64 len = olen_aligned;
3225         u64 last_disko = 0;
3226         u64 last_dest_end = destoff;
3227
3228         ret = -ENOMEM;
3229         buf = vmalloc(btrfs_level_size(root, 0));
3230         if (!buf)
3231                 return ret;
3232
3233         path = btrfs_alloc_path();
3234         if (!path) {
3235                 vfree(buf);
3236                 return ret;
3237         }
3238
3239         path->reada = 2;
3240         /* clone data */
3241         key.objectid = btrfs_ino(src);
3242         key.type = BTRFS_EXTENT_DATA_KEY;
3243         key.offset = off;
3244
3245         while (1) {
3246                 /*
3247                  * note the key will change type as we walk through the
3248                  * tree.
3249                  */
3250                 path->leave_spinning = 1;
3251                 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3252                                 0, 0);
3253                 if (ret < 0)
3254                         goto out;
3255                 /*
3256                  * First search, if no extent item that starts at offset off was
3257                  * found but the previous item is an extent item, it's possible
3258                  * it might overlap our target range, therefore process it.
3259                  */
3260                 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3261                         btrfs_item_key_to_cpu(path->nodes[0], &key,
3262                                               path->slots[0] - 1);
3263                         if (key.type == BTRFS_EXTENT_DATA_KEY)
3264                                 path->slots[0]--;
3265                 }
3266
3267                 nritems = btrfs_header_nritems(path->nodes[0]);
3268 process_slot:
3269                 no_quota = 1;
3270                 if (path->slots[0] >= nritems) {
3271                         ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3272                         if (ret < 0)
3273                                 goto out;
3274                         if (ret > 0)
3275                                 break;
3276                         nritems = btrfs_header_nritems(path->nodes[0]);
3277                 }
3278                 leaf = path->nodes[0];
3279                 slot = path->slots[0];
3280
3281                 btrfs_item_key_to_cpu(leaf, &key, slot);
3282                 if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
3283                     key.objectid != btrfs_ino(src))
3284                         break;
3285
3286                 if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
3287                         struct btrfs_file_extent_item *extent;
3288                         int type;
3289                         u32 size;
3290                         struct btrfs_key new_key;
3291                         u64 disko = 0, diskl = 0;
3292                         u64 datao = 0, datal = 0;
3293                         u8 comp;
3294                         u64 drop_start;
3295
3296                         extent = btrfs_item_ptr(leaf, slot,
3297                                                 struct btrfs_file_extent_item);
3298                         comp = btrfs_file_extent_compression(leaf, extent);
3299                         type = btrfs_file_extent_type(leaf, extent);
3300                         if (type == BTRFS_FILE_EXTENT_REG ||
3301                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3302                                 disko = btrfs_file_extent_disk_bytenr(leaf,
3303                                                                       extent);
3304                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3305                                                                  extent);
3306                                 datao = btrfs_file_extent_offset(leaf, extent);
3307                                 datal = btrfs_file_extent_num_bytes(leaf,
3308                                                                     extent);
3309                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3310                                 /* take upper bound, may be compressed */
3311                                 datal = btrfs_file_extent_ram_bytes(leaf,
3312                                                                     extent);
3313                         }
3314
3315                         /*
3316                          * The first search might have left us at an extent
3317                          * item that ends before our target range's start, can
3318                          * happen if we have holes and NO_HOLES feature enabled.
3319                          */
3320                         if (key.offset + datal <= off) {
3321                                 path->slots[0]++;
3322                                 goto process_slot;
3323                         } else if (key.offset >= off + len) {
3324                                 break;
3325                         }
3326
3327                         size = btrfs_item_size_nr(leaf, slot);
3328                         read_extent_buffer(leaf, buf,
3329                                            btrfs_item_ptr_offset(leaf, slot),
3330                                            size);
3331
3332                         btrfs_release_path(path);
3333                         path->leave_spinning = 0;
3334
3335                         memcpy(&new_key, &key, sizeof(new_key));
3336                         new_key.objectid = btrfs_ino(inode);
3337                         if (off <= key.offset)
3338                                 new_key.offset = key.offset + destoff - off;
3339                         else
3340                                 new_key.offset = destoff;
3341
3342                         /*
3343                          * Deal with a hole that doesn't have an extent item
3344                          * that represents it (NO_HOLES feature enabled).
3345                          * This hole is either in the middle of the cloning
3346                          * range or at the beginning (fully overlaps it or
3347                          * partially overlaps it).
3348                          */
3349                         if (new_key.offset != last_dest_end)
3350                                 drop_start = last_dest_end;
3351                         else
3352                                 drop_start = new_key.offset;
3353
3354                         /*
3355                          * 1 - adjusting old extent (we may have to split it)
3356                          * 1 - add new extent
3357                          * 1 - inode update
3358                          */
3359                         trans = btrfs_start_transaction(root, 3);
3360                         if (IS_ERR(trans)) {
3361                                 ret = PTR_ERR(trans);
3362                                 goto out;
3363                         }
3364
3365                         if (type == BTRFS_FILE_EXTENT_REG ||
3366                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3367                                 /*
3368                                  *    a  | --- range to clone ---|  b
3369                                  * | ------------- extent ------------- |
3370                                  */
3371
3372                                 /* subtract range b */
3373                                 if (key.offset + datal > off + len)
3374                                         datal = off + len - key.offset;
3375
3376                                 /* subtract range a */
3377                                 if (off > key.offset) {
3378                                         datao += off - key.offset;
3379                                         datal -= off - key.offset;
3380                                 }
3381
3382                                 ret = btrfs_drop_extents(trans, root, inode,
3383                                                          drop_start,
3384                                                          new_key.offset + datal,
3385                                                          1);
3386                                 if (ret) {
3387                                         if (ret != -EOPNOTSUPP)
3388                                                 btrfs_abort_transaction(trans,
3389                                                                 root, ret);
3390                                         btrfs_end_transaction(trans, root);
3391                                         goto out;
3392                                 }
3393
3394                                 ret = btrfs_insert_empty_item(trans, root, path,
3395                                                               &new_key, size);
3396                                 if (ret) {
3397                                         btrfs_abort_transaction(trans, root,
3398                                                                 ret);
3399                                         btrfs_end_transaction(trans, root);
3400                                         goto out;
3401                                 }
3402
3403                                 leaf = path->nodes[0];
3404                                 slot = path->slots[0];
3405                                 write_extent_buffer(leaf, buf,
3406                                             btrfs_item_ptr_offset(leaf, slot),
3407                                             size);
3408
3409                                 extent = btrfs_item_ptr(leaf, slot,
3410                                                 struct btrfs_file_extent_item);
3411
3412                                 /* disko == 0 means it's a hole */
3413                                 if (!disko)
3414                                         datao = 0;
3415
3416                                 btrfs_set_file_extent_offset(leaf, extent,
3417                                                              datao);
3418                                 btrfs_set_file_extent_num_bytes(leaf, extent,
3419                                                                 datal);
3420
3421                                 /*
3422                                  * We need to look up the roots that point at
3423                                  * this bytenr and see if the new root does.  If
3424                                  * it does not we need to make sure we update
3425                                  * quotas appropriately.
3426                                  */
3427                                 if (disko && root != BTRFS_I(src)->root &&
3428                                     disko != last_disko) {
3429                                         no_quota = check_ref(trans, root,
3430                                                              disko);
3431                                         if (no_quota < 0) {
3432                                                 btrfs_abort_transaction(trans,
3433                                                                         root,
3434                                                                         ret);
3435                                                 btrfs_end_transaction(trans,
3436                                                                       root);
3437                                                 ret = no_quota;
3438                                                 goto out;
3439                                         }
3440                                 }
3441
3442                                 if (disko) {
3443                                         inode_add_bytes(inode, datal);
3444                                         ret = btrfs_inc_extent_ref(trans, root,
3445                                                         disko, diskl, 0,
3446                                                         root->root_key.objectid,
3447                                                         btrfs_ino(inode),
3448                                                         new_key.offset - datao,
3449                                                         no_quota);
3450                                         if (ret) {
3451                                                 btrfs_abort_transaction(trans,
3452                                                                         root,
3453                                                                         ret);
3454                                                 btrfs_end_transaction(trans,
3455                                                                       root);
3456                                                 goto out;
3457
3458                                         }
3459                                 }
3460                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3461                                 u64 skip = 0;
3462                                 u64 trim = 0;
3463                                 u64 aligned_end = 0;
3464
3465                                 if (off > key.offset) {
3466                                         skip = off - key.offset;
3467                                         new_key.offset += skip;
3468                                 }
3469
3470                                 if (key.offset + datal > off + len)
3471                                         trim = key.offset + datal - (off + len);
3472
3473                                 if (comp && (skip || trim)) {
3474                                         ret = -EINVAL;
3475                                         btrfs_end_transaction(trans, root);
3476                                         goto out;
3477                                 }
3478                                 size -= skip + trim;
3479                                 datal -= skip + trim;
3480
3481                                 aligned_end = ALIGN(new_key.offset + datal,
3482                                                     root->sectorsize);
3483                                 ret = btrfs_drop_extents(trans, root, inode,
3484                                                          drop_start,
3485                                                          aligned_end,
3486                                                          1);
3487                                 if (ret) {
3488                                         if (ret != -EOPNOTSUPP)
3489                                                 btrfs_abort_transaction(trans,
3490                                                         root, ret);
3491                                         btrfs_end_transaction(trans, root);
3492                                         goto out;
3493                                 }
3494
3495                                 ret = btrfs_insert_empty_item(trans, root, path,
3496                                                               &new_key, size);
3497                                 if (ret) {
3498                                         btrfs_abort_transaction(trans, root,
3499                                                                 ret);
3500                                         btrfs_end_transaction(trans, root);
3501                                         goto out;
3502                                 }
3503
3504                                 if (skip) {
3505                                         u32 start =
3506                                           btrfs_file_extent_calc_inline_size(0);
3507                                         memmove(buf+start, buf+start+skip,
3508                                                 datal);
3509                                 }
3510
3511                                 leaf = path->nodes[0];
3512                                 slot = path->slots[0];
3513                                 write_extent_buffer(leaf, buf,
3514                                             btrfs_item_ptr_offset(leaf, slot),
3515                                             size);
3516                                 inode_add_bytes(inode, datal);
3517                         }
3518
3519                         /* If we have an implicit hole (NO_HOLES feature). */
3520                         if (drop_start < new_key.offset)
3521                                 clone_update_extent_map(inode, trans,
3522                                                 NULL, drop_start,
3523                                                 new_key.offset - drop_start);
3524
3525                         clone_update_extent_map(inode, trans, path, 0, 0);
3526
3527                         btrfs_mark_buffer_dirty(leaf);
3528                         btrfs_release_path(path);
3529
3530                         last_dest_end = new_key.offset + datal;
3531                         ret = clone_finish_inode_update(trans, inode,
3532                                                         last_dest_end,
3533                                                         destoff, olen);
3534                         if (ret)
3535                                 goto out;
3536                         if (new_key.offset + datal >= destoff + len)
3537                                 break;
3538                 }
3539                 btrfs_release_path(path);
3540                 key.offset++;
3541         }
3542         ret = 0;
3543
3544         if (last_dest_end < destoff + len) {
3545                 /*
3546                  * We have an implicit hole (NO_HOLES feature is enabled) that
3547                  * fully or partially overlaps our cloning range at its end.
3548                  */
3549                 btrfs_release_path(path);
3550
3551                 /*
3552                  * 1 - remove extent(s)
3553                  * 1 - inode update
3554                  */
3555                 trans = btrfs_start_transaction(root, 2);
3556                 if (IS_ERR(trans)) {
3557                         ret = PTR_ERR(trans);
3558                         goto out;
3559                 }
3560                 ret = btrfs_drop_extents(trans, root, inode,
3561                                          last_dest_end, destoff + len, 1);
3562                 if (ret) {
3563                         if (ret != -EOPNOTSUPP)
3564                                 btrfs_abort_transaction(trans, root, ret);
3565                         btrfs_end_transaction(trans, root);
3566                         goto out;
3567                 }
3568                 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3569                                         destoff + len - last_dest_end);
3570                 ret = clone_finish_inode_update(trans, inode, destoff + len,
3571                                                 destoff, olen);
3572         }
3573
3574 out:
3575         btrfs_free_path(path);
3576         vfree(buf);
3577         return ret;
3578 }
3579
3580 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3581                                        u64 off, u64 olen, u64 destoff)
3582 {
3583         struct inode *inode = file_inode(file);
3584         struct btrfs_root *root = BTRFS_I(inode)->root;
3585         struct fd src_file;
3586         struct inode *src;
3587         int ret;
3588         u64 len = olen;
3589         u64 bs = root->fs_info->sb->s_blocksize;
3590         int same_inode = 0;
3591
3592         /*
3593          * TODO:
3594          * - split compressed inline extents.  annoying: we need to
3595          *   decompress into destination's address_space (the file offset
3596          *   may change, so source mapping won't do), then recompress (or
3597          *   otherwise reinsert) a subrange.
3598          *
3599          * - split destination inode's inline extents.  The inline extents can
3600          *   be either compressed or non-compressed.
3601          */
3602
3603         /* the destination must be opened for writing */
3604         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3605                 return -EINVAL;
3606
3607         if (btrfs_root_readonly(root))
3608                 return -EROFS;
3609
3610         ret = mnt_want_write_file(file);
3611         if (ret)
3612                 return ret;
3613
3614         src_file = fdget(srcfd);
3615         if (!src_file.file) {
3616                 ret = -EBADF;
3617                 goto out_drop_write;
3618         }
3619
3620         ret = -EXDEV;
3621         if (src_file.file->f_path.mnt != file->f_path.mnt)
3622                 goto out_fput;
3623
3624         src = file_inode(src_file.file);
3625
3626         ret = -EINVAL;
3627         if (src == inode)
3628                 same_inode = 1;
3629
3630         /* the src must be open for reading */
3631         if (!(src_file.file->f_mode & FMODE_READ))
3632                 goto out_fput;
3633
3634         /* don't make the dst file partly checksummed */
3635         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3636             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3637                 goto out_fput;
3638
3639         ret = -EISDIR;
3640         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3641                 goto out_fput;
3642
3643         ret = -EXDEV;
3644         if (src->i_sb != inode->i_sb)
3645                 goto out_fput;
3646
3647         if (!same_inode) {
3648                 if (inode < src) {
3649                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3650                         mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3651                 } else {
3652                         mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3653                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3654                 }
3655         } else {
3656                 mutex_lock(&src->i_mutex);
3657         }
3658
3659         /* determine range to clone */
3660         ret = -EINVAL;
3661         if (off + len > src->i_size || off + len < off)
3662                 goto out_unlock;
3663         if (len == 0)
3664                 olen = len = src->i_size - off;
3665         /* if we extend to eof, continue to block boundary */
3666         if (off + len == src->i_size)
3667                 len = ALIGN(src->i_size, bs) - off;
3668
3669         /* verify the end result is block aligned */
3670         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3671             !IS_ALIGNED(destoff, bs))
3672                 goto out_unlock;
3673
3674         /* verify if ranges are overlapped within the same file */
3675         if (same_inode) {
3676                 if (destoff + len > off && destoff < off + len)
3677                         goto out_unlock;
3678         }
3679
3680         if (destoff > inode->i_size) {
3681                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3682                 if (ret)
3683                         goto out_unlock;
3684         }
3685
3686         /*
3687          * Lock the target range too. Right after we replace the file extent
3688          * items in the fs tree (which now point to the cloned data), we might
3689          * have a worker replace them with extent items relative to a write
3690          * operation that was issued before this clone operation (i.e. confront
3691          * with inode.c:btrfs_finish_ordered_io).
3692          */
3693         if (same_inode) {
3694                 u64 lock_start = min_t(u64, off, destoff);
3695                 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3696
3697                 lock_extent_range(src, lock_start, lock_len);
3698         } else {
3699                 lock_extent_range(src, off, len);
3700                 lock_extent_range(inode, destoff, len);
3701         }
3702
3703         ret = btrfs_clone(src, inode, off, olen, len, destoff);
3704
3705         if (same_inode) {
3706                 u64 lock_start = min_t(u64, off, destoff);
3707                 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3708
3709                 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3710         } else {
3711                 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3712                 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3713                               destoff + len - 1);
3714         }
3715         /*
3716          * Truncate page cache pages so that future reads will see the cloned
3717          * data immediately and not the previous data.
3718          */
3719         truncate_inode_pages_range(&inode->i_data, destoff,
3720                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
3721 out_unlock:
3722         if (!same_inode) {
3723                 if (inode < src) {
3724                         mutex_unlock(&src->i_mutex);
3725                         mutex_unlock(&inode->i_mutex);
3726                 } else {
3727                         mutex_unlock(&inode->i_mutex);
3728                         mutex_unlock(&src->i_mutex);
3729                 }
3730         } else {
3731                 mutex_unlock(&src->i_mutex);
3732         }
3733 out_fput:
3734         fdput(src_file);
3735 out_drop_write:
3736         mnt_drop_write_file(file);
3737         return ret;
3738 }
3739
3740 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3741 {
3742         struct btrfs_ioctl_clone_range_args args;
3743
3744         if (copy_from_user(&args, argp, sizeof(args)))
3745                 return -EFAULT;
3746         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3747                                  args.src_length, args.dest_offset);
3748 }
3749
3750 /*
3751  * there are many ways the trans_start and trans_end ioctls can lead
3752  * to deadlocks.  They should only be used by applications that
3753  * basically own the machine, and have a very in depth understanding
3754  * of all the possible deadlocks and enospc problems.
3755  */
3756 static long btrfs_ioctl_trans_start(struct file *file)
3757 {
3758         struct inode *inode = file_inode(file);
3759         struct btrfs_root *root = BTRFS_I(inode)->root;
3760         struct btrfs_trans_handle *trans;
3761         int ret;
3762
3763         ret = -EPERM;
3764         if (!capable(CAP_SYS_ADMIN))
3765                 goto out;
3766
3767         ret = -EINPROGRESS;
3768         if (file->private_data)
3769                 goto out;
3770
3771         ret = -EROFS;
3772         if (btrfs_root_readonly(root))
3773                 goto out;
3774
3775         ret = mnt_want_write_file(file);
3776         if (ret)
3777                 goto out;
3778
3779         atomic_inc(&root->fs_info->open_ioctl_trans);
3780
3781         ret = -ENOMEM;
3782         trans = btrfs_start_ioctl_transaction(root);
3783         if (IS_ERR(trans))
3784                 goto out_drop;
3785
3786         file->private_data = trans;
3787         return 0;
3788
3789 out_drop:
3790         atomic_dec(&root->fs_info->open_ioctl_trans);
3791         mnt_drop_write_file(file);
3792 out:
3793         return ret;
3794 }
3795
3796 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3797 {
3798         struct inode *inode = file_inode(file);
3799         struct btrfs_root *root = BTRFS_I(inode)->root;
3800         struct btrfs_root *new_root;
3801         struct btrfs_dir_item *di;
3802         struct btrfs_trans_handle *trans;
3803         struct btrfs_path *path;
3804         struct btrfs_key location;
3805         struct btrfs_disk_key disk_key;
3806         u64 objectid = 0;
3807         u64 dir_id;
3808         int ret;
3809
3810         if (!capable(CAP_SYS_ADMIN))
3811                 return -EPERM;
3812
3813         ret = mnt_want_write_file(file);
3814         if (ret)
3815                 return ret;
3816
3817         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3818                 ret = -EFAULT;
3819                 goto out;
3820         }
3821
3822         if (!objectid)
3823                 objectid = BTRFS_FS_TREE_OBJECTID;
3824
3825         location.objectid = objectid;
3826         location.type = BTRFS_ROOT_ITEM_KEY;
3827         location.offset = (u64)-1;
3828
3829         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3830         if (IS_ERR(new_root)) {
3831                 ret = PTR_ERR(new_root);
3832                 goto out;
3833         }
3834
3835         path = btrfs_alloc_path();
3836         if (!path) {
3837                 ret = -ENOMEM;
3838                 goto out;
3839         }
3840         path->leave_spinning = 1;
3841
3842         trans = btrfs_start_transaction(root, 1);
3843         if (IS_ERR(trans)) {
3844                 btrfs_free_path(path);
3845                 ret = PTR_ERR(trans);
3846                 goto out;
3847         }
3848
3849         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3850         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3851                                    dir_id, "default", 7, 1);
3852         if (IS_ERR_OR_NULL(di)) {
3853                 btrfs_free_path(path);
3854                 btrfs_end_transaction(trans, root);
3855                 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3856                            "item, this isn't going to work");
3857                 ret = -ENOENT;
3858                 goto out;
3859         }
3860
3861         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3862         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3863         btrfs_mark_buffer_dirty(path->nodes[0]);
3864         btrfs_free_path(path);
3865
3866         btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3867         btrfs_end_transaction(trans, root);
3868 out:
3869         mnt_drop_write_file(file);
3870         return ret;
3871 }
3872
3873 void btrfs_get_block_group_info(struct list_head *groups_list,
3874                                 struct btrfs_ioctl_space_info *space)
3875 {
3876         struct btrfs_block_group_cache *block_group;
3877
3878         space->total_bytes = 0;
3879         space->used_bytes = 0;
3880         space->flags = 0;
3881         list_for_each_entry(block_group, groups_list, list) {
3882                 space->flags = block_group->flags;
3883                 space->total_bytes += block_group->key.offset;
3884                 space->used_bytes +=
3885                         btrfs_block_group_used(&block_group->item);
3886         }
3887 }
3888
3889 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3890 {
3891         struct btrfs_ioctl_space_args space_args;
3892         struct btrfs_ioctl_space_info space;
3893         struct btrfs_ioctl_space_info *dest;
3894         struct btrfs_ioctl_space_info *dest_orig;
3895         struct btrfs_ioctl_space_info __user *user_dest;
3896         struct btrfs_space_info *info;
3897         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3898                        BTRFS_BLOCK_GROUP_SYSTEM,
3899                        BTRFS_BLOCK_GROUP_METADATA,
3900                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3901         int num_types = 4;
3902         int alloc_size;
3903         int ret = 0;
3904         u64 slot_count = 0;
3905         int i, c;
3906
3907         if (copy_from_user(&space_args,
3908                            (struct btrfs_ioctl_space_args __user *)arg,
3909                            sizeof(space_args)))
3910                 return -EFAULT;
3911
3912         for (i = 0; i < num_types; i++) {
3913                 struct btrfs_space_info *tmp;
3914
3915                 info = NULL;
3916                 rcu_read_lock();
3917                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3918                                         list) {
3919                         if (tmp->flags == types[i]) {
3920                                 info = tmp;
3921                                 break;
3922                         }
3923                 }
3924                 rcu_read_unlock();
3925
3926                 if (!info)
3927                         continue;
3928
3929                 down_read(&info->groups_sem);
3930                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3931                         if (!list_empty(&info->block_groups[c]))
3932                                 slot_count++;
3933                 }
3934                 up_read(&info->groups_sem);
3935         }
3936
3937         /*
3938          * Global block reserve, exported as a space_info
3939          */
3940         slot_count++;
3941
3942         /* space_slots == 0 means they are asking for a count */
3943         if (space_args.space_slots == 0) {
3944                 space_args.total_spaces = slot_count;
3945                 goto out;
3946         }
3947
3948         slot_count = min_t(u64, space_args.space_slots, slot_count);
3949
3950         alloc_size = sizeof(*dest) * slot_count;
3951
3952         /* we generally have at most 6 or so space infos, one for each raid
3953          * level.  So, a whole page should be more than enough for everyone
3954          */
3955         if (alloc_size > PAGE_CACHE_SIZE)
3956                 return -ENOMEM;
3957
3958         space_args.total_spaces = 0;
3959         dest = kmalloc(alloc_size, GFP_NOFS);
3960         if (!dest)
3961                 return -ENOMEM;
3962         dest_orig = dest;
3963
3964         /* now we have a buffer to copy into */
3965         for (i = 0; i < num_types; i++) {
3966                 struct btrfs_space_info *tmp;
3967
3968                 if (!slot_count)
3969                         break;
3970
3971                 info = NULL;
3972                 rcu_read_lock();
3973                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3974                                         list) {
3975                         if (tmp->flags == types[i]) {
3976                                 info = tmp;
3977                                 break;
3978                         }
3979                 }
3980                 rcu_read_unlock();
3981
3982                 if (!info)
3983                         continue;
3984                 down_read(&info->groups_sem);
3985                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3986                         if (!list_empty(&info->block_groups[c])) {
3987                                 btrfs_get_block_group_info(
3988                                         &info->block_groups[c], &space);
3989                                 memcpy(dest, &space, sizeof(space));
3990                                 dest++;
3991                                 space_args.total_spaces++;
3992                                 slot_count--;
3993                         }
3994                         if (!slot_count)
3995                                 break;
3996                 }
3997                 up_read(&info->groups_sem);
3998         }
3999
4000         /*
4001          * Add global block reserve
4002          */
4003         if (slot_count) {
4004                 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
4005
4006                 spin_lock(&block_rsv->lock);
4007                 space.total_bytes = block_rsv->size;
4008                 space.used_bytes = block_rsv->size - block_rsv->reserved;
4009                 spin_unlock(&block_rsv->lock);
4010                 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4011                 memcpy(dest, &space, sizeof(space));
4012                 space_args.total_spaces++;
4013         }
4014
4015         user_dest = (struct btrfs_ioctl_space_info __user *)
4016                 (arg + sizeof(struct btrfs_ioctl_space_args));
4017
4018         if (copy_to_user(user_dest, dest_orig, alloc_size))
4019                 ret = -EFAULT;
4020
4021         kfree(dest_orig);
4022 out:
4023         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4024                 ret = -EFAULT;
4025
4026         return ret;
4027 }
4028
4029 /*
4030  * there are many ways the trans_start and trans_end ioctls can lead
4031  * to deadlocks.  They should only be used by applications that
4032  * basically own the machine, and have a very in depth understanding
4033  * of all the possible deadlocks and enospc problems.
4034  */
4035 long btrfs_ioctl_trans_end(struct file *file)
4036 {
4037         struct inode *inode = file_inode(file);
4038         struct btrfs_root *root = BTRFS_I(inode)->root;
4039         struct btrfs_trans_handle *trans;
4040
4041         trans = file->private_data;
4042         if (!trans)
4043                 return -EINVAL;
4044         file->private_data = NULL;
4045
4046         btrfs_end_transaction(trans, root);
4047
4048         atomic_dec(&root->fs_info->open_ioctl_trans);
4049
4050         mnt_drop_write_file(file);
4051         return 0;
4052 }
4053
4054 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4055                                             void __user *argp)
4056 {
4057         struct btrfs_trans_handle *trans;
4058         u64 transid;
4059         int ret;
4060
4061         trans = btrfs_attach_transaction_barrier(root);
4062         if (IS_ERR(trans)) {
4063                 if (PTR_ERR(trans) != -ENOENT)
4064                         return PTR_ERR(trans);
4065
4066                 /* No running transaction, don't bother */
4067                 transid = root->fs_info->last_trans_committed;
4068                 goto out;
4069         }
4070         transid = trans->transid;
4071         ret = btrfs_commit_transaction_async(trans, root, 0);
4072         if (ret) {
4073                 btrfs_end_transaction(trans, root);
4074                 return ret;
4075         }
4076 out:
4077         if (argp)
4078                 if (copy_to_user(argp, &transid, sizeof(transid)))
4079                         return -EFAULT;
4080         return 0;
4081 }
4082
4083 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4084                                            void __user *argp)
4085 {
4086         u64 transid;
4087
4088         if (argp) {
4089                 if (copy_from_user(&transid, argp, sizeof(transid)))
4090                         return -EFAULT;
4091         } else {
4092                 transid = 0;  /* current trans */
4093         }
4094         return btrfs_wait_for_commit(root, transid);
4095 }
4096
4097 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4098 {
4099         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4100         struct btrfs_ioctl_scrub_args *sa;
4101         int ret;
4102
4103         if (!capable(CAP_SYS_ADMIN))
4104                 return -EPERM;
4105
4106         sa = memdup_user(arg, sizeof(*sa));
4107         if (IS_ERR(sa))
4108                 return PTR_ERR(sa);
4109
4110         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4111                 ret = mnt_want_write_file(file);
4112                 if (ret)
4113                         goto out;
4114         }
4115
4116         ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4117                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4118                               0);
4119
4120         if (copy_to_user(arg, sa, sizeof(*sa)))
4121                 ret = -EFAULT;
4122
4123         if (!(sa->flags & BTRFS_SCRUB_READONLY))
4124                 mnt_drop_write_file(file);
4125 out:
4126         kfree(sa);
4127         return ret;
4128 }
4129
4130 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4131 {
4132         if (!capable(CAP_SYS_ADMIN))
4133                 return -EPERM;
4134
4135         return btrfs_scrub_cancel(root->fs_info);
4136 }
4137
4138 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4139                                        void __user *arg)
4140 {
4141         struct btrfs_ioctl_scrub_args *sa;
4142         int ret;
4143
4144         if (!capable(CAP_SYS_ADMIN))
4145                 return -EPERM;
4146
4147         sa = memdup_user(arg, sizeof(*sa));
4148         if (IS_ERR(sa))
4149                 return PTR_ERR(sa);
4150
4151         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4152
4153         if (copy_to_user(arg, sa, sizeof(*sa)))
4154                 ret = -EFAULT;
4155
4156         kfree(sa);
4157         return ret;
4158 }
4159
4160 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4161                                       void __user *arg)
4162 {
4163         struct btrfs_ioctl_get_dev_stats *sa;
4164         int ret;
4165
4166         sa = memdup_user(arg, sizeof(*sa));
4167         if (IS_ERR(sa))
4168                 return PTR_ERR(sa);
4169
4170         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4171                 kfree(sa);
4172                 return -EPERM;
4173         }
4174
4175         ret = btrfs_get_dev_stats(root, sa);
4176
4177         if (copy_to_user(arg, sa, sizeof(*sa)))
4178                 ret = -EFAULT;
4179
4180         kfree(sa);
4181         return ret;
4182 }
4183
4184 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4185 {
4186         struct btrfs_ioctl_dev_replace_args *p;
4187         int ret;
4188
4189         if (!capable(CAP_SYS_ADMIN))
4190                 return -EPERM;
4191
4192         p = memdup_user(arg, sizeof(*p));
4193         if (IS_ERR(p))
4194                 return PTR_ERR(p);
4195
4196         switch (p->cmd) {
4197         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4198                 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4199                         ret = -EROFS;
4200                         goto out;
4201                 }
4202                 if (atomic_xchg(
4203                         &root->fs_info->mutually_exclusive_operation_running,
4204                         1)) {
4205                         ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4206                 } else {
4207                         ret = btrfs_dev_replace_start(root, p);
4208                         atomic_set(
4209                          &root->fs_info->mutually_exclusive_operation_running,
4210                          0);
4211                 }
4212                 break;
4213         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4214                 btrfs_dev_replace_status(root->fs_info, p);
4215                 ret = 0;
4216                 break;
4217         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4218                 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4219                 break;
4220         default:
4221                 ret = -EINVAL;
4222                 break;
4223         }
4224
4225         if (copy_to_user(arg, p, sizeof(*p)))
4226                 ret = -EFAULT;
4227 out:
4228         kfree(p);
4229         return ret;
4230 }
4231
4232 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4233 {
4234         int ret = 0;
4235         int i;
4236         u64 rel_ptr;
4237         int size;
4238         struct btrfs_ioctl_ino_path_args *ipa = NULL;
4239         struct inode_fs_paths *ipath = NULL;
4240         struct btrfs_path *path;
4241
4242         if (!capable(CAP_DAC_READ_SEARCH))
4243                 return -EPERM;
4244
4245         path = btrfs_alloc_path();
4246         if (!path) {
4247                 ret = -ENOMEM;
4248                 goto out;
4249         }
4250
4251         ipa = memdup_user(arg, sizeof(*ipa));
4252         if (IS_ERR(ipa)) {
4253                 ret = PTR_ERR(ipa);
4254                 ipa = NULL;
4255                 goto out;
4256         }
4257
4258         size = min_t(u32, ipa->size, 4096);
4259         ipath = init_ipath(size, root, path);
4260         if (IS_ERR(ipath)) {
4261                 ret = PTR_ERR(ipath);
4262                 ipath = NULL;
4263                 goto out;
4264         }
4265
4266         ret = paths_from_inode(ipa->inum, ipath);
4267         if (ret < 0)
4268                 goto out;
4269
4270         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4271                 rel_ptr = ipath->fspath->val[i] -
4272                           (u64)(unsigned long)ipath->fspath->val;
4273                 ipath->fspath->val[i] = rel_ptr;
4274         }
4275
4276         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4277                            (void *)(unsigned long)ipath->fspath, size);
4278         if (ret) {
4279                 ret = -EFAULT;
4280                 goto out;
4281         }
4282
4283 out:
4284         btrfs_free_path(path);
4285         free_ipath(ipath);
4286         kfree(ipa);
4287
4288         return ret;
4289 }
4290
4291 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4292 {
4293         struct btrfs_data_container *inodes = ctx;
4294         const size_t c = 3 * sizeof(u64);
4295
4296         if (inodes->bytes_left >= c) {
4297                 inodes->bytes_left -= c;
4298                 inodes->val[inodes->elem_cnt] = inum;
4299                 inodes->val[inodes->elem_cnt + 1] = offset;
4300                 inodes->val[inodes->elem_cnt + 2] = root;
4301                 inodes->elem_cnt += 3;
4302         } else {
4303                 inodes->bytes_missing += c - inodes->bytes_left;
4304                 inodes->bytes_left = 0;
4305                 inodes->elem_missed += 3;
4306         }
4307
4308         return 0;
4309 }
4310
4311 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4312                                         void __user *arg)
4313 {
4314         int ret = 0;
4315         int size;
4316         struct btrfs_ioctl_logical_ino_args *loi;
4317         struct btrfs_data_container *inodes = NULL;
4318         struct btrfs_path *path = NULL;
4319
4320         if (!capable(CAP_SYS_ADMIN))
4321                 return -EPERM;
4322
4323         loi = memdup_user(arg, sizeof(*loi));
4324         if (IS_ERR(loi)) {
4325                 ret = PTR_ERR(loi);
4326                 loi = NULL;
4327                 goto out;
4328         }
4329
4330         path = btrfs_alloc_path();
4331         if (!path) {
4332                 ret = -ENOMEM;
4333                 goto out;
4334         }
4335
4336         size = min_t(u32, loi->size, 64 * 1024);
4337         inodes = init_data_container(size);
4338         if (IS_ERR(inodes)) {
4339                 ret = PTR_ERR(inodes);
4340                 inodes = NULL;
4341                 goto out;
4342         }
4343
4344         ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4345                                           build_ino_list, inodes);
4346         if (ret == -EINVAL)
4347                 ret = -ENOENT;
4348         if (ret < 0)
4349                 goto out;
4350
4351         ret = copy_to_user((void *)(unsigned long)loi->inodes,
4352                            (void *)(unsigned long)inodes, size);
4353         if (ret)
4354                 ret = -EFAULT;
4355
4356 out:
4357         btrfs_free_path(path);
4358         vfree(inodes);
4359         kfree(loi);
4360
4361         return ret;
4362 }
4363
4364 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4365                                struct btrfs_ioctl_balance_args *bargs)
4366 {
4367         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4368
4369         bargs->flags = bctl->flags;
4370
4371         if (atomic_read(&fs_info->balance_running))
4372                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4373         if (atomic_read(&fs_info->balance_pause_req))
4374                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4375         if (atomic_read(&fs_info->balance_cancel_req))
4376                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4377
4378         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4379         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4380         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4381
4382         if (lock) {
4383                 spin_lock(&fs_info->balance_lock);
4384                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4385                 spin_unlock(&fs_info->balance_lock);
4386         } else {
4387                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4388         }
4389 }
4390
4391 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4392 {
4393         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4394         struct btrfs_fs_info *fs_info = root->fs_info;
4395         struct btrfs_ioctl_balance_args *bargs;
4396         struct btrfs_balance_control *bctl;
4397         bool need_unlock; /* for mut. excl. ops lock */
4398         int ret;
4399
4400         if (!capable(CAP_SYS_ADMIN))
4401                 return -EPERM;
4402
4403         ret = mnt_want_write_file(file);
4404         if (ret)
4405                 return ret;
4406
4407 again:
4408         if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4409                 mutex_lock(&fs_info->volume_mutex);
4410                 mutex_lock(&fs_info->balance_mutex);
4411                 need_unlock = true;
4412                 goto locked;
4413         }
4414
4415         /*
4416          * mut. excl. ops lock is locked.  Three possibilites:
4417          *   (1) some other op is running
4418          *   (2) balance is running
4419          *   (3) balance is paused -- special case (think resume)
4420          */
4421         mutex_lock(&fs_info->balance_mutex);
4422         if (fs_info->balance_ctl) {
4423                 /* this is either (2) or (3) */
4424                 if (!atomic_read(&fs_info->balance_running)) {
4425                         mutex_unlock(&fs_info->balance_mutex);
4426                         if (!mutex_trylock(&fs_info->volume_mutex))
4427                                 goto again;
4428                         mutex_lock(&fs_info->balance_mutex);
4429
4430                         if (fs_info->balance_ctl &&
4431                             !atomic_read(&fs_info->balance_running)) {
4432                                 /* this is (3) */
4433                                 need_unlock = false;
4434                                 goto locked;
4435                         }
4436
4437                         mutex_unlock(&fs_info->balance_mutex);
4438                         mutex_unlock(&fs_info->volume_mutex);
4439                         goto again;
4440                 } else {
4441                         /* this is (2) */
4442                         mutex_unlock(&fs_info->balance_mutex);
4443                         ret = -EINPROGRESS;
4444                         goto out;
4445                 }
4446         } else {
4447                 /* this is (1) */
4448                 mutex_unlock(&fs_info->balance_mutex);
4449                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4450                 goto out;
4451         }
4452
4453 locked:
4454         BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4455
4456         if (arg) {
4457                 bargs = memdup_user(arg, sizeof(*bargs));
4458                 if (IS_ERR(bargs)) {
4459                         ret = PTR_ERR(bargs);
4460                         goto out_unlock;
4461                 }
4462
4463                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4464                         if (!fs_info->balance_ctl) {
4465                                 ret = -ENOTCONN;
4466                                 goto out_bargs;
4467                         }
4468
4469                         bctl = fs_info->balance_ctl;
4470                         spin_lock(&fs_info->balance_lock);
4471                         bctl->flags |= BTRFS_BALANCE_RESUME;
4472                         spin_unlock(&fs_info->balance_lock);
4473
4474                         goto do_balance;
4475                 }
4476         } else {
4477                 bargs = NULL;
4478         }
4479
4480         if (fs_info->balance_ctl) {
4481                 ret = -EINPROGRESS;
4482                 goto out_bargs;
4483         }
4484
4485         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4486         if (!bctl) {
4487                 ret = -ENOMEM;
4488                 goto out_bargs;
4489         }
4490
4491         bctl->fs_info = fs_info;
4492         if (arg) {
4493                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4494                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4495                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4496
4497                 bctl->flags = bargs->flags;
4498         } else {
4499                 /* balance everything - no filters */
4500                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4501         }
4502
4503 do_balance:
4504         /*
4505          * Ownership of bctl and mutually_exclusive_operation_running
4506          * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
4507          * or, if restriper was paused all the way until unmount, in
4508          * free_fs_info.  mutually_exclusive_operation_running is
4509          * cleared in __cancel_balance.
4510          */
4511         need_unlock = false;
4512
4513         ret = btrfs_balance(bctl, bargs);
4514
4515         if (arg) {
4516                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4517                         ret = -EFAULT;
4518         }
4519
4520 out_bargs:
4521         kfree(bargs);
4522 out_unlock:
4523         mutex_unlock(&fs_info->balance_mutex);
4524         mutex_unlock(&fs_info->volume_mutex);
4525         if (need_unlock)
4526                 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4527 out:
4528         mnt_drop_write_file(file);
4529         return ret;
4530 }
4531
4532 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4533 {
4534         if (!capable(CAP_SYS_ADMIN))
4535                 return -EPERM;
4536
4537         switch (cmd) {
4538         case BTRFS_BALANCE_CTL_PAUSE:
4539                 return btrfs_pause_balance(root->fs_info);
4540         case BTRFS_BALANCE_CTL_CANCEL:
4541                 return btrfs_cancel_balance(root->fs_info);
4542         }
4543
4544         return -EINVAL;
4545 }
4546
4547 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4548                                          void __user *arg)
4549 {
4550         struct btrfs_fs_info *fs_info = root->fs_info;
4551         struct btrfs_ioctl_balance_args *bargs;
4552         int ret = 0;
4553
4554         if (!capable(CAP_SYS_ADMIN))
4555                 return -EPERM;
4556
4557         mutex_lock(&fs_info->balance_mutex);
4558         if (!fs_info->balance_ctl) {
4559                 ret = -ENOTCONN;
4560                 goto out;
4561         }
4562
4563         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4564         if (!bargs) {
4565                 ret = -ENOMEM;
4566                 goto out;
4567         }
4568
4569         update_ioctl_balance_args(fs_info, 1, bargs);
4570
4571         if (copy_to_user(arg, bargs, sizeof(*bargs)))
4572                 ret = -EFAULT;
4573
4574         kfree(bargs);
4575 out:
4576         mutex_unlock(&fs_info->balance_mutex);
4577         return ret;
4578 }
4579
4580 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4581 {
4582         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4583         struct btrfs_ioctl_quota_ctl_args *sa;
4584         struct btrfs_trans_handle *trans = NULL;
4585         int ret;
4586         int err;
4587
4588         if (!capable(CAP_SYS_ADMIN))
4589                 return -EPERM;
4590
4591         ret = mnt_want_write_file(file);
4592         if (ret)
4593                 return ret;
4594
4595         sa = memdup_user(arg, sizeof(*sa));
4596         if (IS_ERR(sa)) {
4597                 ret = PTR_ERR(sa);
4598                 goto drop_write;
4599         }
4600
4601         down_write(&root->fs_info->subvol_sem);
4602         trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4603         if (IS_ERR(trans)) {
4604                 ret = PTR_ERR(trans);
4605                 goto out;
4606         }
4607
4608         switch (sa->cmd) {
4609         case BTRFS_QUOTA_CTL_ENABLE:
4610                 ret = btrfs_quota_enable(trans, root->fs_info);
4611                 break;
4612         case BTRFS_QUOTA_CTL_DISABLE:
4613                 ret = btrfs_quota_disable(trans, root->fs_info);
4614                 break;
4615         default:
4616                 ret = -EINVAL;
4617                 break;
4618         }
4619
4620         err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4621         if (err && !ret)
4622                 ret = err;
4623 out:
4624         kfree(sa);
4625         up_write(&root->fs_info->subvol_sem);
4626 drop_write:
4627         mnt_drop_write_file(file);
4628         return ret;
4629 }
4630
4631 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4632 {
4633         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4634         struct btrfs_ioctl_qgroup_assign_args *sa;
4635         struct btrfs_trans_handle *trans;
4636         int ret;
4637         int err;
4638
4639         if (!capable(CAP_SYS_ADMIN))
4640                 return -EPERM;
4641
4642         ret = mnt_want_write_file(file);
4643         if (ret)
4644                 return ret;
4645
4646         sa = memdup_user(arg, sizeof(*sa));
4647         if (IS_ERR(sa)) {
4648                 ret = PTR_ERR(sa);
4649                 goto drop_write;
4650         }
4651
4652         trans = btrfs_join_transaction(root);
4653         if (IS_ERR(trans)) {
4654                 ret = PTR_ERR(trans);
4655                 goto out;
4656         }
4657
4658         /* FIXME: check if the IDs really exist */
4659         if (sa->assign) {
4660                 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4661                                                 sa->src, sa->dst);
4662         } else {
4663                 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4664                                                 sa->src, sa->dst);
4665         }
4666
4667         err = btrfs_end_transaction(trans, root);
4668         if (err && !ret)
4669                 ret = err;
4670
4671 out:
4672         kfree(sa);
4673 drop_write:
4674         mnt_drop_write_file(file);
4675         return ret;
4676 }
4677
4678 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4679 {
4680         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4681         struct btrfs_ioctl_qgroup_create_args *sa;
4682         struct btrfs_trans_handle *trans;
4683         int ret;
4684         int err;
4685
4686         if (!capable(CAP_SYS_ADMIN))
4687                 return -EPERM;
4688
4689         ret = mnt_want_write_file(file);
4690         if (ret)
4691                 return ret;
4692
4693         sa = memdup_user(arg, sizeof(*sa));
4694         if (IS_ERR(sa)) {
4695                 ret = PTR_ERR(sa);
4696                 goto drop_write;
4697         }
4698
4699         if (!sa->qgroupid) {
4700                 ret = -EINVAL;
4701                 goto out;
4702         }
4703
4704         trans = btrfs_join_transaction(root);
4705         if (IS_ERR(trans)) {
4706                 ret = PTR_ERR(trans);
4707                 goto out;
4708         }
4709
4710         /* FIXME: check if the IDs really exist */
4711         if (sa->create) {
4712                 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4713                                           NULL);
4714         } else {
4715                 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4716         }
4717
4718         err = btrfs_end_transaction(trans, root);
4719         if (err && !ret)
4720                 ret = err;
4721
4722 out:
4723         kfree(sa);
4724 drop_write:
4725         mnt_drop_write_file(file);
4726         return ret;
4727 }
4728
4729 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4730 {
4731         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4732         struct btrfs_ioctl_qgroup_limit_args *sa;
4733         struct btrfs_trans_handle *trans;
4734         int ret;
4735         int err;
4736         u64 qgroupid;
4737
4738         if (!capable(CAP_SYS_ADMIN))
4739                 return -EPERM;
4740
4741         ret = mnt_want_write_file(file);
4742         if (ret)
4743                 return ret;
4744
4745         sa = memdup_user(arg, sizeof(*sa));
4746         if (IS_ERR(sa)) {
4747                 ret = PTR_ERR(sa);
4748                 goto drop_write;
4749         }
4750
4751         trans = btrfs_join_transaction(root);
4752         if (IS_ERR(trans)) {
4753                 ret = PTR_ERR(trans);
4754                 goto out;
4755         }
4756
4757         qgroupid = sa->qgroupid;
4758         if (!qgroupid) {
4759                 /* take the current subvol as qgroup */
4760                 qgroupid = root->root_key.objectid;
4761         }
4762
4763         /* FIXME: check if the IDs really exist */
4764         ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4765
4766         err = btrfs_end_transaction(trans, root);
4767         if (err && !ret)
4768                 ret = err;
4769
4770 out:
4771         kfree(sa);
4772 drop_write:
4773         mnt_drop_write_file(file);
4774         return ret;
4775 }
4776
4777 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4778 {
4779         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4780         struct btrfs_ioctl_quota_rescan_args *qsa;
4781         int ret;
4782
4783         if (!capable(CAP_SYS_ADMIN))
4784                 return -EPERM;
4785
4786         ret = mnt_want_write_file(file);
4787         if (ret)
4788                 return ret;
4789
4790         qsa = memdup_user(arg, sizeof(*qsa));
4791         if (IS_ERR(qsa)) {
4792                 ret = PTR_ERR(qsa);
4793                 goto drop_write;
4794         }
4795
4796         if (qsa->flags) {
4797                 ret = -EINVAL;
4798                 goto out;
4799         }
4800
4801         ret = btrfs_qgroup_rescan(root->fs_info);
4802
4803 out:
4804         kfree(qsa);
4805 drop_write:
4806         mnt_drop_write_file(file);
4807         return ret;
4808 }
4809
4810 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4811 {
4812         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4813         struct btrfs_ioctl_quota_rescan_args *qsa;
4814         int ret = 0;
4815
4816         if (!capable(CAP_SYS_ADMIN))
4817                 return -EPERM;
4818
4819         qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4820         if (!qsa)
4821                 return -ENOMEM;
4822
4823         if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4824                 qsa->flags = 1;
4825                 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4826         }
4827
4828         if (copy_to_user(arg, qsa, sizeof(*qsa)))
4829                 ret = -EFAULT;
4830
4831         kfree(qsa);
4832         return ret;
4833 }
4834
4835 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4836 {
4837         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4838
4839         if (!capable(CAP_SYS_ADMIN))
4840                 return -EPERM;
4841
4842         return btrfs_qgroup_wait_for_completion(root->fs_info);
4843 }
4844
4845 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4846                                             struct btrfs_ioctl_received_subvol_args *sa)
4847 {
4848         struct inode *inode = file_inode(file);
4849         struct btrfs_root *root = BTRFS_I(inode)->root;
4850         struct btrfs_root_item *root_item = &root->root_item;
4851         struct btrfs_trans_handle *trans;
4852         struct timespec ct = CURRENT_TIME;
4853         int ret = 0;
4854         int received_uuid_changed;
4855
4856         if (!inode_owner_or_capable(inode))
4857                 return -EPERM;
4858
4859         ret = mnt_want_write_file(file);
4860         if (ret < 0)
4861                 return ret;
4862
4863         down_write(&root->fs_info->subvol_sem);
4864
4865         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4866                 ret = -EINVAL;
4867                 goto out;
4868         }
4869
4870         if (btrfs_root_readonly(root)) {
4871                 ret = -EROFS;
4872                 goto out;
4873         }
4874
4875         /*
4876          * 1 - root item
4877          * 2 - uuid items (received uuid + subvol uuid)
4878          */
4879         trans = btrfs_start_transaction(root, 3);
4880         if (IS_ERR(trans)) {
4881                 ret = PTR_ERR(trans);
4882                 trans = NULL;
4883                 goto out;
4884         }
4885
4886         sa->rtransid = trans->transid;
4887         sa->rtime.sec = ct.tv_sec;
4888         sa->rtime.nsec = ct.tv_nsec;
4889
4890         received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4891                                        BTRFS_UUID_SIZE);
4892         if (received_uuid_changed &&
4893             !btrfs_is_empty_uuid(root_item->received_uuid))
4894                 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4895                                     root_item->received_uuid,
4896                                     BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4897                                     root->root_key.objectid);
4898         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4899         btrfs_set_root_stransid(root_item, sa->stransid);
4900         btrfs_set_root_rtransid(root_item, sa->rtransid);
4901         btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4902         btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4903         btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4904         btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4905
4906         ret = btrfs_update_root(trans, root->fs_info->tree_root,
4907                                 &root->root_key, &root->root_item);
4908         if (ret < 0) {
4909                 btrfs_end_transaction(trans, root);
4910                 goto out;
4911         }
4912         if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4913                 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4914                                           sa->uuid,
4915                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4916                                           root->root_key.objectid);
4917                 if (ret < 0 && ret != -EEXIST) {
4918                         btrfs_abort_transaction(trans, root, ret);
4919                         goto out;
4920                 }
4921         }
4922         ret = btrfs_commit_transaction(trans, root);
4923         if (ret < 0) {
4924                 btrfs_abort_transaction(trans, root, ret);
4925                 goto out;
4926         }
4927
4928 out:
4929         up_write(&root->fs_info->subvol_sem);
4930         mnt_drop_write_file(file);
4931         return ret;
4932 }
4933
4934 #ifdef CONFIG_64BIT
4935 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4936                                                 void __user *arg)
4937 {
4938         struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4939         struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4940         int ret = 0;
4941
4942         args32 = memdup_user(arg, sizeof(*args32));
4943         if (IS_ERR(args32)) {
4944                 ret = PTR_ERR(args32);
4945                 args32 = NULL;
4946                 goto out;
4947         }
4948
4949         args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4950         if (!args64) {
4951                 ret = -ENOMEM;
4952                 goto out;
4953         }
4954
4955         memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4956         args64->stransid = args32->stransid;
4957         args64->rtransid = args32->rtransid;
4958         args64->stime.sec = args32->stime.sec;
4959         args64->stime.nsec = args32->stime.nsec;
4960         args64->rtime.sec = args32->rtime.sec;
4961         args64->rtime.nsec = args32->rtime.nsec;
4962         args64->flags = args32->flags;
4963
4964         ret = _btrfs_ioctl_set_received_subvol(file, args64);
4965         if (ret)
4966                 goto out;
4967
4968         memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4969         args32->stransid = args64->stransid;
4970         args32->rtransid = args64->rtransid;
4971         args32->stime.sec = args64->stime.sec;
4972         args32->stime.nsec = args64->stime.nsec;
4973         args32->rtime.sec = args64->rtime.sec;
4974         args32->rtime.nsec = args64->rtime.nsec;
4975         args32->flags = args64->flags;
4976
4977         ret = copy_to_user(arg, args32, sizeof(*args32));
4978         if (ret)
4979                 ret = -EFAULT;
4980
4981 out:
4982         kfree(args32);
4983         kfree(args64);
4984         return ret;
4985 }
4986 #endif
4987
4988 static long btrfs_ioctl_set_received_subvol(struct file *file,
4989                                             void __user *arg)
4990 {
4991         struct btrfs_ioctl_received_subvol_args *sa = NULL;
4992         int ret = 0;
4993
4994         sa = memdup_user(arg, sizeof(*sa));
4995         if (IS_ERR(sa)) {
4996                 ret = PTR_ERR(sa);
4997                 sa = NULL;
4998                 goto out;
4999         }
5000
5001         ret = _btrfs_ioctl_set_received_subvol(file, sa);
5002
5003         if (ret)
5004                 goto out;
5005
5006         ret = copy_to_user(arg, sa, sizeof(*sa));
5007         if (ret)
5008                 ret = -EFAULT;
5009
5010 out:
5011         kfree(sa);
5012         return ret;
5013 }
5014
5015 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5016 {
5017         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5018         size_t len;
5019         int ret;
5020         char label[BTRFS_LABEL_SIZE];
5021
5022         spin_lock(&root->fs_info->super_lock);
5023         memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5024         spin_unlock(&root->fs_info->super_lock);
5025
5026         len = strnlen(label, BTRFS_LABEL_SIZE);
5027
5028         if (len == BTRFS_LABEL_SIZE) {
5029                 btrfs_warn(root->fs_info,
5030                         "label is too long, return the first %zu bytes", --len);
5031         }
5032
5033         ret = copy_to_user(arg, label, len);
5034
5035         return ret ? -EFAULT : 0;
5036 }
5037
5038 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5039 {
5040         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5041         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5042         struct btrfs_trans_handle *trans;
5043         char label[BTRFS_LABEL_SIZE];
5044         int ret;
5045
5046         if (!capable(CAP_SYS_ADMIN))
5047                 return -EPERM;
5048
5049         if (copy_from_user(label, arg, sizeof(label)))
5050                 return -EFAULT;
5051
5052         if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5053                 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5054                        BTRFS_LABEL_SIZE - 1);
5055                 return -EINVAL;
5056         }
5057
5058         ret = mnt_want_write_file(file);
5059         if (ret)
5060                 return ret;
5061
5062         trans = btrfs_start_transaction(root, 0);
5063         if (IS_ERR(trans)) {
5064                 ret = PTR_ERR(trans);
5065                 goto out_unlock;
5066         }
5067
5068         spin_lock(&root->fs_info->super_lock);
5069         strcpy(super_block->label, label);
5070         spin_unlock(&root->fs_info->super_lock);
5071         ret = btrfs_commit_transaction(trans, root);
5072
5073 out_unlock:
5074         mnt_drop_write_file(file);
5075         return ret;
5076 }
5077
5078 #define INIT_FEATURE_FLAGS(suffix) \
5079         { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5080           .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5081           .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5082
5083 static int btrfs_ioctl_get_supported_features(struct file *file,
5084                                               void __user *arg)
5085 {
5086         static struct btrfs_ioctl_feature_flags features[3] = {
5087                 INIT_FEATURE_FLAGS(SUPP),
5088                 INIT_FEATURE_FLAGS(SAFE_SET),
5089                 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5090         };
5091
5092         if (copy_to_user(arg, &features, sizeof(features)))
5093                 return -EFAULT;
5094
5095         return 0;
5096 }
5097
5098 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5099 {
5100         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5101         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5102         struct btrfs_ioctl_feature_flags features;
5103
5104         features.compat_flags = btrfs_super_compat_flags(super_block);
5105         features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5106         features.incompat_flags = btrfs_super_incompat_flags(super_block);
5107
5108         if (copy_to_user(arg, &features, sizeof(features)))
5109                 return -EFAULT;
5110
5111         return 0;
5112 }
5113
5114 static int check_feature_bits(struct btrfs_root *root,
5115                               enum btrfs_feature_set set,
5116                               u64 change_mask, u64 flags, u64 supported_flags,
5117                               u64 safe_set, u64 safe_clear)
5118 {
5119         const char *type = btrfs_feature_set_names[set];
5120         char *names;
5121         u64 disallowed, unsupported;
5122         u64 set_mask = flags & change_mask;
5123         u64 clear_mask = ~flags & change_mask;
5124
5125         unsupported = set_mask & ~supported_flags;
5126         if (unsupported) {
5127                 names = btrfs_printable_features(set, unsupported);
5128                 if (names) {
5129                         btrfs_warn(root->fs_info,
5130                            "this kernel does not support the %s feature bit%s",
5131                            names, strchr(names, ',') ? "s" : "");
5132                         kfree(names);
5133                 } else
5134                         btrfs_warn(root->fs_info,
5135                            "this kernel does not support %s bits 0x%llx",
5136                            type, unsupported);
5137                 return -EOPNOTSUPP;
5138         }
5139
5140         disallowed = set_mask & ~safe_set;
5141         if (disallowed) {
5142                 names = btrfs_printable_features(set, disallowed);
5143                 if (names) {
5144                         btrfs_warn(root->fs_info,
5145                            "can't set the %s feature bit%s while mounted",
5146                            names, strchr(names, ',') ? "s" : "");
5147                         kfree(names);
5148                 } else
5149                         btrfs_warn(root->fs_info,
5150                            "can't set %s bits 0x%llx while mounted",
5151                            type, disallowed);
5152                 return -EPERM;
5153         }
5154
5155         disallowed = clear_mask & ~safe_clear;
5156         if (disallowed) {
5157                 names = btrfs_printable_features(set, disallowed);
5158                 if (names) {
5159                         btrfs_warn(root->fs_info,
5160                            "can't clear the %s feature bit%s while mounted",
5161                            names, strchr(names, ',') ? "s" : "");
5162                         kfree(names);
5163                 } else
5164                         btrfs_warn(root->fs_info,
5165                            "can't clear %s bits 0x%llx while mounted",
5166                            type, disallowed);
5167                 return -EPERM;
5168         }
5169
5170         return 0;
5171 }
5172
5173 #define check_feature(root, change_mask, flags, mask_base)      \
5174 check_feature_bits(root, FEAT_##mask_base, change_mask, flags,  \
5175                    BTRFS_FEATURE_ ## mask_base ## _SUPP,        \
5176                    BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,    \
5177                    BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5178
5179 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5180 {
5181         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5182         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5183         struct btrfs_ioctl_feature_flags flags[2];
5184         struct btrfs_trans_handle *trans;
5185         u64 newflags;
5186         int ret;
5187
5188         if (!capable(CAP_SYS_ADMIN))
5189                 return -EPERM;
5190
5191         if (copy_from_user(flags, arg, sizeof(flags)))
5192                 return -EFAULT;
5193
5194         /* Nothing to do */
5195         if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5196             !flags[0].incompat_flags)
5197                 return 0;
5198
5199         ret = check_feature(root, flags[0].compat_flags,
5200                             flags[1].compat_flags, COMPAT);
5201         if (ret)
5202                 return ret;
5203
5204         ret = check_feature(root, flags[0].compat_ro_flags,
5205                             flags[1].compat_ro_flags, COMPAT_RO);
5206         if (ret)
5207                 return ret;
5208
5209         ret = check_feature(root, flags[0].incompat_flags,
5210                             flags[1].incompat_flags, INCOMPAT);
5211         if (ret)
5212                 return ret;
5213
5214         trans = btrfs_start_transaction(root, 0);
5215         if (IS_ERR(trans))
5216                 return PTR_ERR(trans);
5217
5218         spin_lock(&root->fs_info->super_lock);
5219         newflags = btrfs_super_compat_flags(super_block);
5220         newflags |= flags[0].compat_flags & flags[1].compat_flags;
5221         newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5222         btrfs_set_super_compat_flags(super_block, newflags);
5223
5224         newflags = btrfs_super_compat_ro_flags(super_block);
5225         newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5226         newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5227         btrfs_set_super_compat_ro_flags(super_block, newflags);
5228
5229         newflags = btrfs_super_incompat_flags(super_block);
5230         newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5231         newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5232         btrfs_set_super_incompat_flags(super_block, newflags);
5233         spin_unlock(&root->fs_info->super_lock);
5234
5235         return btrfs_commit_transaction(trans, root);
5236 }
5237
5238 long btrfs_ioctl(struct file *file, unsigned int
5239                 cmd, unsigned long arg)
5240 {
5241         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5242         void __user *argp = (void __user *)arg;
5243
5244         switch (cmd) {
5245         case FS_IOC_GETFLAGS:
5246                 return btrfs_ioctl_getflags(file, argp);
5247         case FS_IOC_SETFLAGS:
5248                 return btrfs_ioctl_setflags(file, argp);
5249         case FS_IOC_GETVERSION:
5250                 return btrfs_ioctl_getversion(file, argp);
5251         case FITRIM:
5252                 return btrfs_ioctl_fitrim(file, argp);
5253         case BTRFS_IOC_SNAP_CREATE:
5254                 return btrfs_ioctl_snap_create(file, argp, 0);
5255         case BTRFS_IOC_SNAP_CREATE_V2:
5256                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5257         case BTRFS_IOC_SUBVOL_CREATE:
5258                 return btrfs_ioctl_snap_create(file, argp, 1);
5259         case BTRFS_IOC_SUBVOL_CREATE_V2:
5260                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5261         case BTRFS_IOC_SNAP_DESTROY:
5262                 return btrfs_ioctl_snap_destroy(file, argp);
5263         case BTRFS_IOC_SUBVOL_GETFLAGS:
5264                 return btrfs_ioctl_subvol_getflags(file, argp);
5265         case BTRFS_IOC_SUBVOL_SETFLAGS:
5266                 return btrfs_ioctl_subvol_setflags(file, argp);
5267         case BTRFS_IOC_DEFAULT_SUBVOL:
5268                 return btrfs_ioctl_default_subvol(file, argp);
5269         case BTRFS_IOC_DEFRAG:
5270                 return btrfs_ioctl_defrag(file, NULL);
5271         case BTRFS_IOC_DEFRAG_RANGE:
5272                 return btrfs_ioctl_defrag(file, argp);
5273         case BTRFS_IOC_RESIZE:
5274                 return btrfs_ioctl_resize(file, argp);
5275         case BTRFS_IOC_ADD_DEV:
5276                 return btrfs_ioctl_add_dev(root, argp);
5277         case BTRFS_IOC_RM_DEV:
5278                 return btrfs_ioctl_rm_dev(file, argp);
5279         case BTRFS_IOC_FS_INFO:
5280                 return btrfs_ioctl_fs_info(root, argp);
5281         case BTRFS_IOC_DEV_INFO:
5282                 return btrfs_ioctl_dev_info(root, argp);
5283         case BTRFS_IOC_BALANCE:
5284                 return btrfs_ioctl_balance(file, NULL);
5285         case BTRFS_IOC_CLONE:
5286                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5287         case BTRFS_IOC_CLONE_RANGE:
5288                 return btrfs_ioctl_clone_range(file, argp);
5289         case BTRFS_IOC_TRANS_START:
5290                 return btrfs_ioctl_trans_start(file);
5291         case BTRFS_IOC_TRANS_END:
5292                 return btrfs_ioctl_trans_end(file);
5293         case BTRFS_IOC_TREE_SEARCH:
5294                 return btrfs_ioctl_tree_search(file, argp);
5295         case BTRFS_IOC_TREE_SEARCH_V2:
5296                 return btrfs_ioctl_tree_search_v2(file, argp);
5297         case BTRFS_IOC_INO_LOOKUP:
5298                 return btrfs_ioctl_ino_lookup(file, argp);
5299         case BTRFS_IOC_INO_PATHS:
5300                 return btrfs_ioctl_ino_to_path(root, argp);
5301         case BTRFS_IOC_LOGICAL_INO:
5302                 return btrfs_ioctl_logical_to_ino(root, argp);
5303         case BTRFS_IOC_SPACE_INFO:
5304                 return btrfs_ioctl_space_info(root, argp);
5305         case BTRFS_IOC_SYNC: {
5306                 int ret;
5307
5308                 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5309                 if (ret)
5310                         return ret;
5311                 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
5312                 return ret;
5313         }
5314         case BTRFS_IOC_START_SYNC:
5315                 return btrfs_ioctl_start_sync(root, argp);
5316         case BTRFS_IOC_WAIT_SYNC:
5317                 return btrfs_ioctl_wait_sync(root, argp);
5318         case BTRFS_IOC_SCRUB:
5319                 return btrfs_ioctl_scrub(file, argp);
5320         case BTRFS_IOC_SCRUB_CANCEL:
5321                 return btrfs_ioctl_scrub_cancel(root, argp);
5322         case BTRFS_IOC_SCRUB_PROGRESS:
5323                 return btrfs_ioctl_scrub_progress(root, argp);
5324         case BTRFS_IOC_BALANCE_V2:
5325                 return btrfs_ioctl_balance(file, argp);
5326         case BTRFS_IOC_BALANCE_CTL:
5327                 return btrfs_ioctl_balance_ctl(root, arg);
5328         case BTRFS_IOC_BALANCE_PROGRESS:
5329                 return btrfs_ioctl_balance_progress(root, argp);
5330         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5331                 return btrfs_ioctl_set_received_subvol(file, argp);
5332 #ifdef CONFIG_64BIT
5333         case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5334                 return btrfs_ioctl_set_received_subvol_32(file, argp);
5335 #endif
5336         case BTRFS_IOC_SEND:
5337                 return btrfs_ioctl_send(file, argp);
5338         case BTRFS_IOC_GET_DEV_STATS:
5339                 return btrfs_ioctl_get_dev_stats(root, argp);
5340         case BTRFS_IOC_QUOTA_CTL:
5341                 return btrfs_ioctl_quota_ctl(file, argp);
5342         case BTRFS_IOC_QGROUP_ASSIGN:
5343                 return btrfs_ioctl_qgroup_assign(file, argp);
5344         case BTRFS_IOC_QGROUP_CREATE:
5345                 return btrfs_ioctl_qgroup_create(file, argp);
5346         case BTRFS_IOC_QGROUP_LIMIT:
5347                 return btrfs_ioctl_qgroup_limit(file, argp);
5348         case BTRFS_IOC_QUOTA_RESCAN:
5349                 return btrfs_ioctl_quota_rescan(file, argp);
5350         case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5351                 return btrfs_ioctl_quota_rescan_status(file, argp);
5352         case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5353                 return btrfs_ioctl_quota_rescan_wait(file, argp);
5354         case BTRFS_IOC_DEV_REPLACE:
5355                 return btrfs_ioctl_dev_replace(root, argp);
5356         case BTRFS_IOC_GET_FSLABEL:
5357                 return btrfs_ioctl_get_fslabel(file, argp);
5358         case BTRFS_IOC_SET_FSLABEL:
5359                 return btrfs_ioctl_set_fslabel(file, argp);
5360         case BTRFS_IOC_FILE_EXTENT_SAME:
5361                 return btrfs_ioctl_file_extent_same(file, argp);
5362         case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5363                 return btrfs_ioctl_get_supported_features(file, argp);
5364         case BTRFS_IOC_GET_FEATURES:
5365                 return btrfs_ioctl_get_features(file, argp);
5366         case BTRFS_IOC_SET_FEATURES:
5367                 return btrfs_ioctl_set_features(file, argp);
5368         }
5369
5370         return -ENOTTY;
5371 }