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