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                 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
 336                 if (ret && ret != -ENODATA)
 337                         goto out_drop;
 338                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 339         }
 340
 341         trans = btrfs_start_transaction(root, 1);
 342         if (IS_ERR(trans)) {
 343                 ret = PTR_ERR(trans);
 344                 goto out_drop;
 345         }
 346
 347         btrfs_update_iflags(inode);
 348         inode_inc_iversion(inode);
 349         inode->i_ctime = CURRENT_TIME;
 350         ret = btrfs_update_inode(trans, root, inode);
 351
 352         btrfs_end_transaction(trans, root);
 353  out_drop:
 354         if (ret) {
 355                 ip->flags = ip_oldflags;
 356                 inode->i_flags = i_oldflags;
 357         }
 358
 359  out_unlock:
 360         mutex_unlock(&inode->i_mutex);
 361         mnt_drop_write_file(file);
 362         return ret;
 363 }
 364
 365 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 366 {
 367         struct inode *inode = file_inode(file);
 368
 369         return put_user(inode->i_generation, arg);
 370 }
 371
 372 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 373 {
 374         struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
 375         struct btrfs_device *device;
 376         struct request_queue *q;
 377         struct fstrim_range range;
 378         u64 minlen = ULLONG_MAX;
 379         u64 num_devices = 0;
 380         u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 381         int ret;
 382
 383         if (!capable(CAP_SYS_ADMIN))
 384                 return -EPERM;
 385
 386         rcu_read_lock();
 387         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 388                                 dev_list) {
 389                 if (!device->bdev)
 390                         continue;
 391                 q = bdev_get_queue(device->bdev);
 392                 if (blk_queue_discard(q)) {
 393                         num_devices++;
 394                         minlen = min((u64)q->limits.discard_granularity,
 395                                      minlen);
 396                 }
 397         }
 398         rcu_read_unlock();
 399
 400         if (!num_devices)
 401                 return -EOPNOTSUPP;
 402         if (copy_from_user(&range, arg, sizeof(range)))
 403                 return -EFAULT;
 404         if (range.start > total_bytes ||
 405             range.len < fs_info->sb->s_blocksize)
 406                 return -EINVAL;
 407
 408         range.len = min(range.len, total_bytes - range.start);
 409         range.minlen = max(range.minlen, minlen);
 410         ret = btrfs_trim_fs(fs_info->tree_root, &range);
 411         if (ret < 0)
 412                 return ret;
 413
 414         if (copy_to_user(arg, &range, sizeof(range)))
 415                 return -EFAULT;
 416
 417         return 0;
 418 }
 419
 420 int btrfs_is_empty_uuid(u8 *uuid)
 421 {
 422         int i;
 423
 424         for (i = 0; i < BTRFS_UUID_SIZE; i++) {
 425                 if (uuid[i])
 426                         return 0;
 427         }
 428         return 1;
 429 }
 430
 431 static noinline int create_subvol(struct inode *dir,
 432                                   struct dentry *dentry,
 433                                   char *name, int namelen,
 434                                   u64 *async_transid,
 435                                   struct btrfs_qgroup_inherit *inherit)
 436 {
 437         struct btrfs_trans_handle *trans;
 438         struct btrfs_key key;
 439         struct btrfs_root_item root_item;
 440         struct btrfs_inode_item *inode_item;
 441         struct extent_buffer *leaf;
 442         struct btrfs_root *root = BTRFS_I(dir)->root;
 443         struct btrfs_root *new_root;
 444         struct btrfs_block_rsv block_rsv;
 445         struct timespec cur_time = CURRENT_TIME;
 446         struct inode *inode;
 447         int ret;
 448         int err;
 449         u64 objectid;
 450         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 451         u64 index = 0;
 452         u64 qgroup_reserved;
 453         uuid_le new_uuid;
 454
 455         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 456         if (ret)
 457                 return ret;
 458
 459         /*
 460          * Don't create subvolume whose level is not zero. Or qgroup will be
 461          * screwed up since it assume subvolme qgroup's level to be 0.
 462          */
 463         if (btrfs_qgroup_level(objectid))
 464                 return -ENOSPC;
 465
 466         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 467         /*
 468          * The same as the snapshot creation, please see the comment
 469          * of create_snapshot().
 470          */
 471         ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
 472                                                8, &qgroup_reserved, false);
 473         if (ret)
 474                 return ret;
 475
 476         trans = btrfs_start_transaction(root, 0);
 477         if (IS_ERR(trans)) {
 478                 ret = PTR_ERR(trans);
 479                 btrfs_subvolume_release_metadata(root, &block_rsv,
 480                                                  qgroup_reserved);
 481                 return ret;
 482         }
 483         trans->block_rsv = &block_rsv;
 484         trans->bytes_reserved = block_rsv.size;
 485
 486         ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
 487         if (ret)
 488                 goto fail;
 489
 490         leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
 491         if (IS_ERR(leaf)) {
 492                 ret = PTR_ERR(leaf);
 493                 goto fail;
 494         }
 495
 496         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 497         btrfs_set_header_bytenr(leaf, leaf->start);
 498         btrfs_set_header_generation(leaf, trans->transid);
 499         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 500         btrfs_set_header_owner(leaf, objectid);
 501
 502         write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
 503                             BTRFS_FSID_SIZE);
 504         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 505                             btrfs_header_chunk_tree_uuid(leaf),
 506                             BTRFS_UUID_SIZE);
 507         btrfs_mark_buffer_dirty(leaf);
 508
 509         memset(&root_item, 0, sizeof(root_item));
 510
 511         inode_item = &root_item.inode;
 512         btrfs_set_stack_inode_generation(inode_item, 1);
 513         btrfs_set_stack_inode_size(inode_item, 3);
 514         btrfs_set_stack_inode_nlink(inode_item, 1);
 515         btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
 516         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 517
 518         btrfs_set_root_flags(&root_item, 0);
 519         btrfs_set_root_limit(&root_item, 0);
 520         btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 521
 522         btrfs_set_root_bytenr(&root_item, leaf->start);
 523         btrfs_set_root_generation(&root_item, trans->transid);
 524         btrfs_set_root_level(&root_item, 0);
 525         btrfs_set_root_refs(&root_item, 1);
 526         btrfs_set_root_used(&root_item, leaf->len);
 527         btrfs_set_root_last_snapshot(&root_item, 0);
 528
 529         btrfs_set_root_generation_v2(&root_item,
 530                         btrfs_root_generation(&root_item));
 531         uuid_le_gen(&new_uuid);
 532         memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
 533         btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
 534         btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
 535         root_item.ctime = root_item.otime;
 536         btrfs_set_root_ctransid(&root_item, trans->transid);
 537         btrfs_set_root_otransid(&root_item, trans->transid);
 538
 539         btrfs_tree_unlock(leaf);
 540         free_extent_buffer(leaf);
 541         leaf = NULL;
 542
 543         btrfs_set_root_dirid(&root_item, new_dirid);
 544
 545         key.objectid = objectid;
 546         key.offset = 0;
 547         key.type = BTRFS_ROOT_ITEM_KEY;
 548         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 549                                 &root_item);
 550         if (ret)
 551                 goto fail;
 552
 553         key.offset = (u64)-1;
 554         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 555         if (IS_ERR(new_root)) {
 556                 ret = PTR_ERR(new_root);
 557                 btrfs_abort_transaction(trans, root, ret);
 558                 goto fail;
 559         }
 560
 561         btrfs_record_root_in_trans(trans, new_root);
 562
 563         ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
 564         if (ret) {
 565                 /* We potentially lose an unused inode item here */
 566                 btrfs_abort_transaction(trans, root, ret);
 567                 goto fail;
 568         }
 569
 570         /*
 571          * insert the directory item
 572          */
 573         ret = btrfs_set_inode_index(dir, &index);
 574         if (ret) {
 575                 btrfs_abort_transaction(trans, root, ret);
 576                 goto fail;
 577         }
 578
 579         ret = btrfs_insert_dir_item(trans, root,
 580                                     name, namelen, dir, &key,
 581                                     BTRFS_FT_DIR, index);
 582         if (ret) {
 583                 btrfs_abort_transaction(trans, root, ret);
 584                 goto fail;
 585         }
 586
 587         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 588         ret = btrfs_update_inode(trans, root, dir);
 589         BUG_ON(ret);
 590
 591         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 592                                  objectid, root->root_key.objectid,
 593                                  btrfs_ino(dir), index, name, namelen);
 594         BUG_ON(ret);
 595
 596         ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
 597                                   root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
 598                                   objectid);
 599         if (ret)
 600                 btrfs_abort_transaction(trans, root, ret);
 601
 602 fail:
 603         trans->block_rsv = NULL;
 604         trans->bytes_reserved = 0;
 605         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 606
 607         if (async_transid) {
 608                 *async_transid = trans->transid;
 609                 err = btrfs_commit_transaction_async(trans, root, 1);
 610                 if (err)
 611                         err = btrfs_commit_transaction(trans, root);
 612         } else {
 613                 err = btrfs_commit_transaction(trans, root);
 614         }
 615         if (err && !ret)
 616                 ret = err;
 617
 618         if (!ret) {
 619                 inode = btrfs_lookup_dentry(dir, dentry);
 620                 if (IS_ERR(inode))
 621                         return PTR_ERR(inode);
 622                 d_instantiate(dentry, inode);
 623         }
 624         return ret;
 625 }
 626
 627 static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
 628 {
 629         s64 writers;
 630         DEFINE_WAIT(wait);
 631
 632         do {
 633                 prepare_to_wait(&root->subv_writers->wait, &wait,
 634                                 TASK_UNINTERRUPTIBLE);
 635
 636                 writers = percpu_counter_sum(&root->subv_writers->counter);
 637                 if (writers)
 638                         schedule();
 639
 640                 finish_wait(&root->subv_writers->wait, &wait);
 641         } while (writers);
 642 }
 643
 644 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 645                            struct dentry *dentry, char *name, int namelen,
 646                            u64 *async_transid, bool readonly,
 647                            struct btrfs_qgroup_inherit *inherit)
 648 {
 649         struct inode *inode;
 650         struct btrfs_pending_snapshot *pending_snapshot;
 651         struct btrfs_trans_handle *trans;
 652         int ret;
 653
 654         if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
 655                 return -EINVAL;
 656
 657         atomic_inc(&root->will_be_snapshoted);
 658         smp_mb__after_atomic();
 659         btrfs_wait_for_no_snapshoting_writes(root);
 660
 661         ret = btrfs_start_delalloc_inodes(root, 0);
 662         if (ret)
 663                 goto out;
 664
 665         btrfs_wait_ordered_extents(root, -1);
 666
 667         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 668         if (!pending_snapshot) {
 669                 ret = -ENOMEM;
 670                 goto out;
 671         }
 672
 673         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 674                              BTRFS_BLOCK_RSV_TEMP);
 675         /*
 676          * 1 - parent dir inode
 677          * 2 - dir entries
 678          * 1 - root item
 679          * 2 - root ref/backref
 680          * 1 - root of snapshot
 681          * 1 - UUID item
 682          */
 683         ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 684                                         &pending_snapshot->block_rsv, 8,
 685                                         &pending_snapshot->qgroup_reserved,
 686                                         false);
 687         if (ret)
 688                 goto free;
 689
 690         pending_snapshot->dentry = dentry;
 691         pending_snapshot->root = root;
 692         pending_snapshot->readonly = readonly;
 693         pending_snapshot->dir = dir;
 694         pending_snapshot->inherit = inherit;
 695
 696         trans = btrfs_start_transaction(root, 0);
 697         if (IS_ERR(trans)) {
 698                 ret = PTR_ERR(trans);
 699                 goto fail;
 700         }
 701
 702         spin_lock(&root->fs_info->trans_lock);
 703         list_add(&pending_snapshot->list,
 704                  &trans->transaction->pending_snapshots);
 705         spin_unlock(&root->fs_info->trans_lock);
 706         if (async_transid) {
 707                 *async_transid = trans->transid;
 708                 ret = btrfs_commit_transaction_async(trans,
 709                                      root->fs_info->extent_root, 1);
 710                 if (ret)
 711                         ret = btrfs_commit_transaction(trans, root);
 712         } else {
 713                 ret = btrfs_commit_transaction(trans,
 714                                                root->fs_info->extent_root);
 715         }
 716         if (ret)
 717                 goto fail;
 718
 719         ret = pending_snapshot->error;
 720         if (ret)
 721                 goto fail;
 722
 723         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 724         if (ret)
 725                 goto fail;
 726
 727         inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
 728         if (IS_ERR(inode)) {
 729                 ret = PTR_ERR(inode);
 730                 goto fail;
 731         }
 732
 733         d_instantiate(dentry, inode);
 734         ret = 0;
 735 fail:
 736         btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
 737                                          &pending_snapshot->block_rsv,
 738                                          pending_snapshot->qgroup_reserved);
 739 free:
 740         kfree(pending_snapshot);
 741 out:
 742         if (atomic_dec_and_test(&root->will_be_snapshoted))
 743                 wake_up_atomic_t(&root->will_be_snapshoted);
 744         return ret;
 745 }
 746
 747 /*  copy of may_delete in fs/namei.c()
 748  *      Check whether we can remove a link victim from directory dir, check
 749  *  whether the type of victim is right.
 750  *  1. We can't do it if dir is read-only (done in permission())
 751  *  2. We should have write and exec permissions on dir
 752  *  3. We can't remove anything from append-only dir
 753  *  4. We can't do anything with immutable dir (done in permission())
 754  *  5. If the sticky bit on dir is set we should either
 755  *      a. be owner of dir, or
 756  *      b. be owner of victim, or
 757  *      c. have CAP_FOWNER capability
 758  *  6. If the victim is append-only or immutable we can't do antyhing with
 759  *     links pointing to it.
 760  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 761  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 762  *  9. We can't remove a root or mountpoint.
 763  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 764  *     nfs_async_unlink().
 765  */
 766
 767 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
 768 {
 769         int error;
 770
 771         if (d_really_is_negative(victim))
 772                 return -ENOENT;
 773
 774         BUG_ON(d_inode(victim->d_parent) != dir);
 775         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 776
 777         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 778         if (error)
 779                 return error;
 780         if (IS_APPEND(dir))
 781                 return -EPERM;
 782         if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
 783             IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
 784                 return -EPERM;
 785         if (isdir) {
 786                 if (!d_is_dir(victim))
 787                         return -ENOTDIR;
 788                 if (IS_ROOT(victim))
 789                         return -EBUSY;
 790         } else if (d_is_dir(victim))
 791                 return -EISDIR;
 792         if (IS_DEADDIR(dir))
 793                 return -ENOENT;
 794         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 795                 return -EBUSY;
 796         return 0;
 797 }
 798
 799 /* copy of may_create in fs/namei.c() */
 800 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 801 {
 802         if (d_really_is_positive(child))
 803                 return -EEXIST;
 804         if (IS_DEADDIR(dir))
 805                 return -ENOENT;
 806         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 807 }
 808
 809 /*
 810  * Create a new subvolume below @parent.  This is largely modeled after
 811  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 812  * inside this filesystem so it's quite a bit simpler.
 813  */
 814 static noinline int btrfs_mksubvol(struct path *parent,
 815                                    char *name, int namelen,
 816                                    struct btrfs_root *snap_src,
 817                                    u64 *async_transid, bool readonly,
 818                                    struct btrfs_qgroup_inherit *inherit)
 819 {
 820         struct inode *dir  = d_inode(parent->dentry);
 821         struct dentry *dentry;
 822         int error;
 823
 824         error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
 825         if (error == -EINTR)
 826                 return error;
 827
 828         dentry = lookup_one_len(name, parent->dentry, namelen);
 829         error = PTR_ERR(dentry);
 830         if (IS_ERR(dentry))
 831                 goto out_unlock;
 832
 833         error = -EEXIST;
 834         if (d_really_is_positive(dentry))
 835                 goto out_dput;
 836
 837         error = btrfs_may_create(dir, dentry);
 838         if (error)
 839                 goto out_dput;
 840
 841         /*
 842          * even if this name doesn't exist, we may get hash collisions.
 843          * check for them now when we can safely fail
 844          */
 845         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 846                                                dir->i_ino, name,
 847                                                namelen);
 848         if (error)
 849                 goto out_dput;
 850
 851         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 852
 853         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 854                 goto out_up_read;
 855
 856         if (snap_src) {
 857                 error = create_snapshot(snap_src, dir, dentry, name, namelen,
 858                                         async_transid, readonly, inherit);
 859         } else {
 860                 error = create_subvol(dir, dentry, name, namelen,
 861                                       async_transid, inherit);
 862         }
 863         if (!error)
 864                 fsnotify_mkdir(dir, dentry);
 865 out_up_read:
 866         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 867 out_dput:
 868         dput(dentry);
 869 out_unlock:
 870         mutex_unlock(&dir->i_mutex);
 871         return error;
 872 }
 873
 874 /*
 875  * When we're defragging a range, we don't want to kick it off again
 876  * if it is really just waiting for delalloc to send it down.
 877  * If we find a nice big extent or delalloc range for the bytes in the
 878  * file you want to defrag, we return 0 to let you know to skip this
 879  * part of the file
 880  */
 881 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
 882 {
 883         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 884         struct extent_map *em = NULL;
 885         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 886         u64 end;
 887
 888         read_lock(&em_tree->lock);
 889         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 890         read_unlock(&em_tree->lock);
 891
 892         if (em) {
 893                 end = extent_map_end(em);
 894                 free_extent_map(em);
 895                 if (end - offset > thresh)
 896                         return 0;
 897         }
 898         /* if we already have a nice delalloc here, just stop */
 899         thresh /= 2;
 900         end = count_range_bits(io_tree, &offset, offset + thresh,
 901                                thresh, EXTENT_DELALLOC, 1);
 902         if (end >= thresh)
 903                 return 0;
 904         return 1;
 905 }
 906
 907 /*
 908  * helper function to walk through a file and find extents
 909  * newer than a specific transid, and smaller than thresh.
 910  *
 911  * This is used by the defragging code to find new and small
 912  * extents
 913  */
 914 static int find_new_extents(struct btrfs_root *root,
 915                             struct inode *inode, u64 newer_than,
 916                             u64 *off, u32 thresh)
 917 {
 918         struct btrfs_path *path;
 919         struct btrfs_key min_key;
 920         struct extent_buffer *leaf;
 921         struct btrfs_file_extent_item *extent;
 922         int type;
 923         int ret;
 924         u64 ino = btrfs_ino(inode);
 925
 926         path = btrfs_alloc_path();
 927         if (!path)
 928                 return -ENOMEM;
 929
 930         min_key.objectid = ino;
 931         min_key.type = BTRFS_EXTENT_DATA_KEY;
 932         min_key.offset = *off;
 933
 934         while (1) {
 935                 ret = btrfs_search_forward(root, &min_key, path, newer_than);
 936                 if (ret != 0)
 937                         goto none;
 938 process_slot:
 939                 if (min_key.objectid != ino)
 940                         goto none;
 941                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 942                         goto none;
 943
 944                 leaf = path->nodes[0];
 945                 extent = btrfs_item_ptr(leaf, path->slots[0],
 946                                         struct btrfs_file_extent_item);
 947
 948                 type = btrfs_file_extent_type(leaf, extent);
 949                 if (type == BTRFS_FILE_EXTENT_REG &&
 950                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 951                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 952                         *off = min_key.offset;
 953                         btrfs_free_path(path);
 954                         return 0;
 955                 }
 956
 957                 path->slots[0]++;
 958                 if (path->slots[0] < btrfs_header_nritems(leaf)) {
 959                         btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
 960                         goto process_slot;
 961                 }
 962
 963                 if (min_key.offset == (u64)-1)
 964                         goto none;
 965
 966                 min_key.offset++;
 967                 btrfs_release_path(path);
 968         }
 969 none:
 970         btrfs_free_path(path);
 971         return -ENOENT;
 972 }
 973
 974 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 975 {
 976         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 977         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 978         struct extent_map *em;
 979         u64 len = PAGE_CACHE_SIZE;
 980
 981         /*
 982          * hopefully we have this extent in the tree already, try without
 983          * the full extent lock
 984          */
 985         read_lock(&em_tree->lock);
 986         em = lookup_extent_mapping(em_tree, start, len);
 987         read_unlock(&em_tree->lock);
 988
 989         if (!em) {
 990                 struct extent_state *cached = NULL;
 991                 u64 end = start + len - 1;
 992
 993                 /* get the big lock and read metadata off disk */
 994                 lock_extent_bits(io_tree, start, end, 0, &cached);
 995                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 996                 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
 997
 998                 if (IS_ERR(em))
 999                         return NULL;
1000         }
1001
1002         return em;
1003 }
1004
1005 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1006 {
1007         struct extent_map *next;
1008         bool ret = true;
1009
1010         /* this is the last extent */
1011         if (em->start + em->len >= i_size_read(inode))
1012                 return false;
1013
1014         next = defrag_lookup_extent(inode, em->start + em->len);
1015         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1016                 ret = false;
1017         else if ((em->block_start + em->block_len == next->block_start) &&
1018                  (em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
1019                 ret = false;
1020
1021         free_extent_map(next);
1022         return ret;
1023 }
1024
1025 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1026                                u64 *last_len, u64 *skip, u64 *defrag_end,
1027                                int compress)
1028 {
1029         struct extent_map *em;
1030         int ret = 1;
1031         bool next_mergeable = true;
1032
1033         /*
1034          * make sure that once we start defragging an extent, we keep on
1035          * defragging it
1036          */
1037         if (start < *defrag_end)
1038                 return 1;
1039
1040         *skip = 0;
1041
1042         em = defrag_lookup_extent(inode, start);
1043         if (!em)
1044                 return 0;
1045
1046         /* this will cover holes, and inline extents */
1047         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1048                 ret = 0;
1049                 goto out;
1050         }
1051
1052         next_mergeable = defrag_check_next_extent(inode, em);
1053         /*
1054          * we hit a real extent, if it is big or the next extent is not a
1055          * real extent, don't bother defragging it
1056          */
1057         if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1058             (em->len >= thresh || !next_mergeable))
1059                 ret = 0;
1060 out:
1061         /*
1062          * last_len ends up being a counter of how many bytes we've defragged.
1063          * every time we choose not to defrag an extent, we reset *last_len
1064          * so that the next tiny extent will force a defrag.
1065          *
1066          * The end result of this is that tiny extents before a single big
1067          * extent will force at least part of that big extent to be defragged.
1068          */
1069         if (ret) {
1070                 *defrag_end = extent_map_end(em);
1071         } else {
1072                 *last_len = 0;
1073                 *skip = extent_map_end(em);
1074                 *defrag_end = 0;
1075         }
1076
1077         free_extent_map(em);
1078         return ret;
1079 }
1080
1081 /*
1082  * it doesn't do much good to defrag one or two pages
1083  * at a time.  This pulls in a nice chunk of pages
1084  * to COW and defrag.
1085  *
1086  * It also makes sure the delalloc code has enough
1087  * dirty data to avoid making new small extents as part
1088  * of the defrag
1089  *
1090  * It's a good idea to start RA on this range
1091  * before calling this.
1092  */
1093 static int cluster_pages_for_defrag(struct inode *inode,
1094                                     struct page **pages,
1095                                     unsigned long start_index,
1096                                     unsigned long num_pages)
1097 {
1098         unsigned long file_end;
1099         u64 isize = i_size_read(inode);
1100         u64 page_start;
1101         u64 page_end;
1102         u64 page_cnt;
1103         int ret;
1104         int i;
1105         int i_done;
1106         struct btrfs_ordered_extent *ordered;
1107         struct extent_state *cached_state = NULL;
1108         struct extent_io_tree *tree;
1109         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1110
1111         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1112         if (!isize || start_index > file_end)
1113                 return 0;
1114
1115         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1116
1117         ret = btrfs_delalloc_reserve_space(inode,
1118                                            page_cnt << PAGE_CACHE_SHIFT);
1119         if (ret)
1120                 return ret;
1121         i_done = 0;
1122         tree = &BTRFS_I(inode)->io_tree;
1123
1124         /* step one, lock all the pages */
1125         for (i = 0; i < page_cnt; i++) {
1126                 struct page *page;
1127 again:
1128                 page = find_or_create_page(inode->i_mapping,
1129                                            start_index + i, mask);
1130                 if (!page)
1131                         break;
1132
1133                 page_start = page_offset(page);
1134                 page_end = page_start + PAGE_CACHE_SIZE - 1;
1135                 while (1) {
1136                         lock_extent_bits(tree, page_start, page_end,
1137                                          0, &cached_state);
1138                         ordered = btrfs_lookup_ordered_extent(inode,
1139                                                               page_start);
1140                         unlock_extent_cached(tree, page_start, page_end,
1141                                              &cached_state, GFP_NOFS);
1142                         if (!ordered)
1143                                 break;
1144
1145                         unlock_page(page);
1146                         btrfs_start_ordered_extent(inode, ordered, 1);
1147                         btrfs_put_ordered_extent(ordered);
1148                         lock_page(page);
1149                         /*
1150                          * we unlocked the page above, so we need check if
1151                          * it was released or not.
1152                          */
1153                         if (page->mapping != inode->i_mapping) {
1154                                 unlock_page(page);
1155                                 page_cache_release(page);
1156                                 goto again;
1157                         }
1158                 }
1159
1160                 if (!PageUptodate(page)) {
1161                         btrfs_readpage(NULL, page);
1162                         lock_page(page);
1163                         if (!PageUptodate(page)) {
1164                                 unlock_page(page);
1165                                 page_cache_release(page);
1166                                 ret = -EIO;
1167                                 break;
1168                         }
1169                 }
1170
1171                 if (page->mapping != inode->i_mapping) {
1172                         unlock_page(page);
1173                         page_cache_release(page);
1174                         goto again;
1175                 }
1176
1177                 pages[i] = page;
1178                 i_done++;
1179         }
1180         if (!i_done || ret)
1181                 goto out;
1182
1183         if (!(inode->i_sb->s_flags & MS_ACTIVE))
1184                 goto out;
1185
1186         /*
1187          * so now we have a nice long stream of locked
1188          * and up to date pages, lets wait on them
1189          */
1190         for (i = 0; i < i_done; i++)
1191                 wait_on_page_writeback(pages[i]);
1192
1193         page_start = page_offset(pages[0]);
1194         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1195
1196         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1197                          page_start, page_end - 1, 0, &cached_state);
1198         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1199                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1200                           EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1201                           &cached_state, GFP_NOFS);
1202
1203         if (i_done != page_cnt) {
1204                 spin_lock(&BTRFS_I(inode)->lock);
1205                 BTRFS_I(inode)->outstanding_extents++;
1206                 spin_unlock(&BTRFS_I(inode)->lock);
1207                 btrfs_delalloc_release_space(inode,
1208                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1209         }
1210
1211
1212         set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1213                           &cached_state, GFP_NOFS);
1214
1215         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1216                              page_start, page_end - 1, &cached_state,
1217                              GFP_NOFS);
1218
1219         for (i = 0; i < i_done; i++) {
1220                 clear_page_dirty_for_io(pages[i]);
1221                 ClearPageChecked(pages[i]);
1222                 set_page_extent_mapped(pages[i]);
1223                 set_page_dirty(pages[i]);
1224                 unlock_page(pages[i]);
1225                 page_cache_release(pages[i]);
1226         }
1227         return i_done;
1228 out:
1229         for (i = 0; i < i_done; i++) {
1230                 unlock_page(pages[i]);
1231                 page_cache_release(pages[i]);
1232         }
1233         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1234         return ret;
1235
1236 }
1237
1238 int btrfs_defrag_file(struct inode *inode, struct file *file,
1239                       struct btrfs_ioctl_defrag_range_args *range,
1240                       u64 newer_than, unsigned long max_to_defrag)
1241 {
1242         struct btrfs_root *root = BTRFS_I(inode)->root;
1243         struct file_ra_state *ra = NULL;
1244         unsigned long last_index;
1245         u64 isize = i_size_read(inode);
1246         u64 last_len = 0;
1247         u64 skip = 0;
1248         u64 defrag_end = 0;
1249         u64 newer_off = range->start;
1250         unsigned long i;
1251         unsigned long ra_index = 0;
1252         int ret;
1253         int defrag_count = 0;
1254         int compress_type = BTRFS_COMPRESS_ZLIB;
1255         u32 extent_thresh = range->extent_thresh;
1256         unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1257         unsigned long cluster = max_cluster;
1258         u64 new_align = ~((u64)128 * 1024 - 1);
1259         struct page **pages = NULL;
1260
1261         if (isize == 0)
1262                 return 0;
1263
1264         if (range->start >= isize)
1265                 return -EINVAL;
1266
1267         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1268                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1269                         return -EINVAL;
1270                 if (range->compress_type)
1271                         compress_type = range->compress_type;
1272         }
1273
1274         if (extent_thresh == 0)
1275                 extent_thresh = 256 * 1024;
1276
1277         /*
1278          * if we were not given a file, allocate a readahead
1279          * context
1280          */
1281         if (!file) {
1282                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1283                 if (!ra)
1284                         return -ENOMEM;
1285                 file_ra_state_init(ra, inode->i_mapping);
1286         } else {
1287                 ra = &file->f_ra;
1288         }
1289
1290         pages = kmalloc_array(max_cluster, sizeof(struct page *),
1291                         GFP_NOFS);
1292         if (!pages) {
1293                 ret = -ENOMEM;
1294                 goto out_ra;
1295         }
1296
1297         /* find the last page to defrag */
1298         if (range->start + range->len > range->start) {
1299                 last_index = min_t(u64, isize - 1,
1300                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1301         } else {
1302                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1303         }
1304
1305         if (newer_than) {
1306                 ret = find_new_extents(root, inode, newer_than,
1307                                        &newer_off, 64 * 1024);
1308                 if (!ret) {
1309                         range->start = newer_off;
1310                         /*
1311                          * we always align our defrag to help keep
1312                          * the extents in the file evenly spaced
1313                          */
1314                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1315                 } else
1316                         goto out_ra;
1317         } else {
1318                 i = range->start >> PAGE_CACHE_SHIFT;
1319         }
1320         if (!max_to_defrag)
1321                 max_to_defrag = last_index - i + 1;
1322
1323         /*
1324          * make writeback starts from i, so the defrag range can be
1325          * written sequentially.
1326          */
1327         if (i < inode->i_mapping->writeback_index)
1328                 inode->i_mapping->writeback_index = i;
1329
1330         while (i <= last_index && defrag_count < max_to_defrag &&
1331                (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
1332                 /*
1333                  * make sure we stop running if someone unmounts
1334                  * the FS
1335                  */
1336                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1337                         break;
1338
1339                 if (btrfs_defrag_cancelled(root->fs_info)) {
1340                         printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1341                         ret = -EAGAIN;
1342                         break;
1343                 }
1344
1345                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1346                                          extent_thresh, &last_len, &skip,
1347                                          &defrag_end, range->flags &
1348                                          BTRFS_DEFRAG_RANGE_COMPRESS)) {
1349                         unsigned long next;
1350                         /*
1351                          * the should_defrag function tells us how much to skip
1352                          * bump our counter by the suggested amount
1353                          */
1354                         next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
1355                         i = max(i + 1, next);
1356                         continue;
1357                 }
1358
1359                 if (!newer_than) {
1360                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1361                                    PAGE_CACHE_SHIFT) - i;
1362                         cluster = min(cluster, max_cluster);
1363                 } else {
1364                         cluster = max_cluster;
1365                 }
1366
1367                 if (i + cluster > ra_index) {
1368                         ra_index = max(i, ra_index);
1369                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1370                                        cluster);
1371                         ra_index += cluster;
1372                 }
1373
1374                 mutex_lock(&inode->i_mutex);
1375                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1376                         BTRFS_I(inode)->force_compress = compress_type;
1377                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1378                 if (ret < 0) {
1379                         mutex_unlock(&inode->i_mutex);
1380                         goto out_ra;
1381                 }
1382
1383                 defrag_count += ret;
1384                 balance_dirty_pages_ratelimited(inode->i_mapping);
1385                 mutex_unlock(&inode->i_mutex);
1386
1387                 if (newer_than) {
1388                         if (newer_off == (u64)-1)
1389                                 break;
1390
1391                         if (ret > 0)
1392                                 i += ret;
1393
1394                         newer_off = max(newer_off + 1,
1395                                         (u64)i << PAGE_CACHE_SHIFT);
1396
1397                         ret = find_new_extents(root, inode,
1398                                                newer_than, &newer_off,
1399                                                64 * 1024);
1400                         if (!ret) {
1401                                 range->start = newer_off;
1402                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1403                         } else {
1404                                 break;
1405                         }
1406                 } else {
1407                         if (ret > 0) {
1408                                 i += ret;
1409                                 last_len += ret << PAGE_CACHE_SHIFT;
1410                         } else {
1411                                 i++;
1412                                 last_len = 0;
1413                         }
1414                 }
1415         }
1416
1417         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1418                 filemap_flush(inode->i_mapping);
1419                 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1420                              &BTRFS_I(inode)->runtime_flags))
1421                         filemap_flush(inode->i_mapping);
1422         }
1423
1424         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1425                 /* the filemap_flush will queue IO into the worker threads, but
1426                  * we have to make sure the IO is actually started and that
1427                  * ordered extents get created before we return
1428                  */
1429                 atomic_inc(&root->fs_info->async_submit_draining);
1430                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1431                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1432                         wait_event(root->fs_info->async_submit_wait,
1433                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1434                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1435                 }
1436                 atomic_dec(&root->fs_info->async_submit_draining);
1437         }
1438
1439         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1440                 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1441         }
1442
1443         ret = defrag_count;
1444
1445 out_ra:
1446         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1447                 mutex_lock(&inode->i_mutex);
1448                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1449                 mutex_unlock(&inode->i_mutex);
1450         }
1451         if (!file)
1452                 kfree(ra);
1453         kfree(pages);
1454         return ret;
1455 }
1456
1457 static noinline int btrfs_ioctl_resize(struct file *file,
1458                                         void __user *arg)
1459 {
1460         u64 new_size;
1461         u64 old_size;
1462         u64 devid = 1;
1463         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1464         struct btrfs_ioctl_vol_args *vol_args;
1465         struct btrfs_trans_handle *trans;
1466         struct btrfs_device *device = NULL;
1467         char *sizestr;
1468         char *retptr;
1469         char *devstr = NULL;
1470         int ret = 0;
1471         int mod = 0;
1472
1473         if (!capable(CAP_SYS_ADMIN))
1474                 return -EPERM;
1475
1476         ret = mnt_want_write_file(file);
1477         if (ret)
1478                 return ret;
1479
1480         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1481                         1)) {
1482                 mnt_drop_write_file(file);
1483                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1484         }
1485
1486         mutex_lock(&root->fs_info->volume_mutex);
1487         vol_args = memdup_user(arg, sizeof(*vol_args));
1488         if (IS_ERR(vol_args)) {
1489                 ret = PTR_ERR(vol_args);
1490                 goto out;
1491         }
1492
1493         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1494
1495         sizestr = vol_args->name;
1496         devstr = strchr(sizestr, ':');
1497         if (devstr) {
1498                 sizestr = devstr + 1;
1499                 *devstr = '\0';
1500                 devstr = vol_args->name;
1501                 ret = kstrtoull(devstr, 10, &devid);
1502                 if (ret)
1503                         goto out_free;
1504                 if (!devid) {
1505                         ret = -EINVAL;
1506                         goto out_free;
1507                 }
1508                 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1509         }
1510
1511         device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1512         if (!device) {
1513                 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1514                        devid);
1515                 ret = -ENODEV;
1516                 goto out_free;
1517         }
1518
1519         if (!device->writeable) {
1520                 btrfs_info(root->fs_info,
1521                            "resizer unable to apply on readonly device %llu",
1522                        devid);
1523                 ret = -EPERM;
1524                 goto out_free;
1525         }
1526
1527         if (!strcmp(sizestr, "max"))
1528                 new_size = device->bdev->bd_inode->i_size;
1529         else {
1530                 if (sizestr[0] == '-') {
1531                         mod = -1;
1532                         sizestr++;
1533                 } else if (sizestr[0] == '+') {
1534                         mod = 1;
1535                         sizestr++;
1536                 }
1537                 new_size = memparse(sizestr, &retptr);
1538                 if (*retptr != '\0' || new_size == 0) {
1539                         ret = -EINVAL;
1540                         goto out_free;
1541                 }
1542         }
1543
1544         if (device->is_tgtdev_for_dev_replace) {
1545                 ret = -EPERM;
1546                 goto out_free;
1547         }
1548
1549         old_size = btrfs_device_get_total_bytes(device);
1550
1551         if (mod < 0) {
1552                 if (new_size > old_size) {
1553                         ret = -EINVAL;
1554                         goto out_free;
1555                 }
1556                 new_size = old_size - new_size;
1557         } else if (mod > 0) {
1558                 if (new_size > ULLONG_MAX - old_size) {
1559                         ret = -ERANGE;
1560                         goto out_free;
1561                 }
1562                 new_size = old_size + new_size;
1563         }
1564
1565         if (new_size < 256 * 1024 * 1024) {
1566                 ret = -EINVAL;
1567                 goto out_free;
1568         }
1569         if (new_size > device->bdev->bd_inode->i_size) {
1570                 ret = -EFBIG;
1571                 goto out_free;
1572         }
1573
1574         new_size = div_u64(new_size, root->sectorsize);
1575         new_size *= root->sectorsize;
1576
1577         printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1578                       rcu_str_deref(device->name), new_size);
1579
1580         if (new_size > old_size) {
1581                 trans = btrfs_start_transaction(root, 0);
1582                 if (IS_ERR(trans)) {
1583                         ret = PTR_ERR(trans);
1584                         goto out_free;
1585                 }
1586                 ret = btrfs_grow_device(trans, device, new_size);
1587                 btrfs_commit_transaction(trans, root);
1588         } else if (new_size < old_size) {
1589                 ret = btrfs_shrink_device(device, new_size);
1590         } /* equal, nothing need to do */
1591
1592 out_free:
1593         kfree(vol_args);
1594 out:
1595         mutex_unlock(&root->fs_info->volume_mutex);
1596         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1597         mnt_drop_write_file(file);
1598         return ret;
1599 }
1600
1601 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1602                                 char *name, unsigned long fd, int subvol,
1603                                 u64 *transid, bool readonly,
1604                                 struct btrfs_qgroup_inherit *inherit)
1605 {
1606         int namelen;
1607         int ret = 0;
1608
1609         ret = mnt_want_write_file(file);
1610         if (ret)
1611                 goto out;
1612
1613         namelen = strlen(name);
1614         if (strchr(name, '/')) {
1615                 ret = -EINVAL;
1616                 goto out_drop_write;
1617         }
1618
1619         if (name[0] == '.' &&
1620            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1621                 ret = -EEXIST;
1622                 goto out_drop_write;
1623         }
1624
1625         if (subvol) {
1626                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1627                                      NULL, transid, readonly, inherit);
1628         } else {
1629                 struct fd src = fdget(fd);
1630                 struct inode *src_inode;
1631                 if (!src.file) {
1632                         ret = -EINVAL;
1633                         goto out_drop_write;
1634                 }
1635
1636                 src_inode = file_inode(src.file);
1637                 if (src_inode->i_sb != file_inode(file)->i_sb) {
1638                         btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1639                                    "Snapshot src from another FS");
1640                         ret = -EXDEV;
1641                 } else if (!inode_owner_or_capable(src_inode)) {
1642                         /*
1643                          * Subvolume creation is not restricted, but snapshots
1644                          * are limited to own subvolumes only
1645                          */
1646                         ret = -EPERM;
1647                 } else {
1648                         ret = btrfs_mksubvol(&file->f_path, name, namelen,
1649                                              BTRFS_I(src_inode)->root,
1650                                              transid, readonly, inherit);
1651                 }
1652                 fdput(src);
1653         }
1654 out_drop_write:
1655         mnt_drop_write_file(file);
1656 out:
1657         return ret;
1658 }
1659
1660 static noinline int btrfs_ioctl_snap_create(struct file *file,
1661                                             void __user *arg, int subvol)
1662 {
1663         struct btrfs_ioctl_vol_args *vol_args;
1664         int ret;
1665
1666         vol_args = memdup_user(arg, sizeof(*vol_args));
1667         if (IS_ERR(vol_args))
1668                 return PTR_ERR(vol_args);
1669         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1670
1671         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1672                                               vol_args->fd, subvol,
1673                                               NULL, false, NULL);
1674
1675         kfree(vol_args);
1676         return ret;
1677 }
1678
1679 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1680                                                void __user *arg, int subvol)
1681 {
1682         struct btrfs_ioctl_vol_args_v2 *vol_args;
1683         int ret;
1684         u64 transid = 0;
1685         u64 *ptr = NULL;
1686         bool readonly = false;
1687         struct btrfs_qgroup_inherit *inherit = NULL;
1688
1689         vol_args = memdup_user(arg, sizeof(*vol_args));
1690         if (IS_ERR(vol_args))
1691                 return PTR_ERR(vol_args);
1692         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1693
1694         if (vol_args->flags &
1695             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1696               BTRFS_SUBVOL_QGROUP_INHERIT)) {
1697                 ret = -EOPNOTSUPP;
1698                 goto free_args;
1699         }
1700
1701         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1702                 ptr = &transid;
1703         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1704                 readonly = true;
1705         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1706                 if (vol_args->size > PAGE_CACHE_SIZE) {
1707                         ret = -EINVAL;
1708                         goto free_args;
1709                 }
1710                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1711                 if (IS_ERR(inherit)) {
1712                         ret = PTR_ERR(inherit);
1713                         goto free_args;
1714                 }
1715         }
1716
1717         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1718                                               vol_args->fd, subvol, ptr,
1719                                               readonly, inherit);
1720         if (ret)
1721                 goto free_inherit;
1722
1723         if (ptr && copy_to_user(arg +
1724                                 offsetof(struct btrfs_ioctl_vol_args_v2,
1725                                         transid),
1726                                 ptr, sizeof(*ptr)))
1727                 ret = -EFAULT;
1728
1729 free_inherit:
1730         kfree(inherit);
1731 free_args:
1732         kfree(vol_args);
1733         return ret;
1734 }
1735
1736 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1737                                                 void __user *arg)
1738 {
1739         struct inode *inode = file_inode(file);
1740         struct btrfs_root *root = BTRFS_I(inode)->root;
1741         int ret = 0;
1742         u64 flags = 0;
1743
1744         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1745                 return -EINVAL;
1746
1747         down_read(&root->fs_info->subvol_sem);
1748         if (btrfs_root_readonly(root))
1749                 flags |= BTRFS_SUBVOL_RDONLY;
1750         up_read(&root->fs_info->subvol_sem);
1751
1752         if (copy_to_user(arg, &flags, sizeof(flags)))
1753                 ret = -EFAULT;
1754
1755         return ret;
1756 }
1757
1758 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1759                                               void __user *arg)
1760 {
1761         struct inode *inode = file_inode(file);
1762         struct btrfs_root *root = BTRFS_I(inode)->root;
1763         struct btrfs_trans_handle *trans;
1764         u64 root_flags;
1765         u64 flags;
1766         int ret = 0;
1767
1768         if (!inode_owner_or_capable(inode))
1769                 return -EPERM;
1770
1771         ret = mnt_want_write_file(file);
1772         if (ret)
1773                 goto out;
1774
1775         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1776                 ret = -EINVAL;
1777                 goto out_drop_write;
1778         }
1779
1780         if (copy_from_user(&flags, arg, sizeof(flags))) {
1781                 ret = -EFAULT;
1782                 goto out_drop_write;
1783         }
1784
1785         if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1786                 ret = -EINVAL;
1787                 goto out_drop_write;
1788         }
1789
1790         if (flags & ~BTRFS_SUBVOL_RDONLY) {
1791                 ret = -EOPNOTSUPP;
1792                 goto out_drop_write;
1793         }
1794
1795         down_write(&root->fs_info->subvol_sem);
1796
1797         /* nothing to do */
1798         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1799                 goto out_drop_sem;
1800
1801         root_flags = btrfs_root_flags(&root->root_item);
1802         if (flags & BTRFS_SUBVOL_RDONLY) {
1803                 btrfs_set_root_flags(&root->root_item,
1804                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1805         } else {
1806                 /*
1807                  * Block RO -> RW transition if this subvolume is involved in
1808                  * send
1809                  */
1810                 spin_lock(&root->root_item_lock);
1811                 if (root->send_in_progress == 0) {
1812                         btrfs_set_root_flags(&root->root_item,
1813                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1814                         spin_unlock(&root->root_item_lock);
1815                 } else {
1816                         spin_unlock(&root->root_item_lock);
1817                         btrfs_warn(root->fs_info,
1818                         "Attempt to set subvolume %llu read-write during send",
1819                                         root->root_key.objectid);
1820                         ret = -EPERM;
1821                         goto out_drop_sem;
1822                 }
1823         }
1824
1825         trans = btrfs_start_transaction(root, 1);
1826         if (IS_ERR(trans)) {
1827                 ret = PTR_ERR(trans);
1828                 goto out_reset;
1829         }
1830
1831         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1832                                 &root->root_key, &root->root_item);
1833
1834         btrfs_commit_transaction(trans, root);
1835 out_reset:
1836         if (ret)
1837                 btrfs_set_root_flags(&root->root_item, root_flags);
1838 out_drop_sem:
1839         up_write(&root->fs_info->subvol_sem);
1840 out_drop_write:
1841         mnt_drop_write_file(file);
1842 out:
1843         return ret;
1844 }
1845
1846 /*
1847  * helper to check if the subvolume references other subvolumes
1848  */
1849 static noinline int may_destroy_subvol(struct btrfs_root *root)
1850 {
1851         struct btrfs_path *path;
1852         struct btrfs_dir_item *di;
1853         struct btrfs_key key;
1854         u64 dir_id;
1855         int ret;
1856
1857         path = btrfs_alloc_path();
1858         if (!path)
1859                 return -ENOMEM;
1860
1861         /* Make sure this root isn't set as the default subvol */
1862         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1863         di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1864                                    dir_id, "default", 7, 0);
1865         if (di && !IS_ERR(di)) {
1866                 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1867                 if (key.objectid == root->root_key.objectid) {
1868                         ret = -EPERM;
1869                         btrfs_err(root->fs_info, "deleting default subvolume "
1870                                   "%llu is not allowed", key.objectid);
1871                         goto out;
1872                 }
1873                 btrfs_release_path(path);
1874         }
1875
1876         key.objectid = root->root_key.objectid;
1877         key.type = BTRFS_ROOT_REF_KEY;
1878         key.offset = (u64)-1;
1879
1880         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1881                                 &key, path, 0, 0);
1882         if (ret < 0)
1883                 goto out;
1884         BUG_ON(ret == 0);
1885
1886         ret = 0;
1887         if (path->slots[0] > 0) {
1888                 path->slots[0]--;
1889                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1890                 if (key.objectid == root->root_key.objectid &&
1891                     key.type == BTRFS_ROOT_REF_KEY)
1892                         ret = -ENOTEMPTY;
1893         }
1894 out:
1895         btrfs_free_path(path);
1896         return ret;
1897 }
1898
1899 static noinline int key_in_sk(struct btrfs_key *key,
1900                               struct btrfs_ioctl_search_key *sk)
1901 {
1902         struct btrfs_key test;
1903         int ret;
1904
1905         test.objectid = sk->min_objectid;
1906         test.type = sk->min_type;
1907         test.offset = sk->min_offset;
1908
1909         ret = btrfs_comp_cpu_keys(key, &test);
1910         if (ret < 0)
1911                 return 0;
1912
1913         test.objectid = sk->max_objectid;
1914         test.type = sk->max_type;
1915         test.offset = sk->max_offset;
1916
1917         ret = btrfs_comp_cpu_keys(key, &test);
1918         if (ret > 0)
1919                 return 0;
1920         return 1;
1921 }
1922
1923 static noinline int copy_to_sk(struct btrfs_root *root,
1924                                struct btrfs_path *path,
1925                                struct btrfs_key *key,
1926                                struct btrfs_ioctl_search_key *sk,
1927                                size_t *buf_size,
1928                                char __user *ubuf,
1929                                unsigned long *sk_offset,
1930                                int *num_found)
1931 {
1932         u64 found_transid;
1933         struct extent_buffer *leaf;
1934         struct btrfs_ioctl_search_header sh;
1935         unsigned long item_off;
1936         unsigned long item_len;
1937         int nritems;
1938         int i;
1939         int slot;
1940         int ret = 0;
1941
1942         leaf = path->nodes[0];
1943         slot = path->slots[0];
1944         nritems = btrfs_header_nritems(leaf);
1945
1946         if (btrfs_header_generation(leaf) > sk->max_transid) {
1947                 i = nritems;
1948                 goto advance_key;
1949         }
1950         found_transid = btrfs_header_generation(leaf);
1951
1952         for (i = slot; i < nritems; i++) {
1953                 item_off = btrfs_item_ptr_offset(leaf, i);
1954                 item_len = btrfs_item_size_nr(leaf, i);
1955
1956                 btrfs_item_key_to_cpu(leaf, key, i);
1957                 if (!key_in_sk(key, sk))
1958                         continue;
1959
1960                 if (sizeof(sh) + item_len > *buf_size) {
1961                         if (*num_found) {
1962                                 ret = 1;
1963                                 goto out;
1964                         }
1965
1966                         /*
1967                          * return one empty item back for v1, which does not
1968                          * handle -EOVERFLOW
1969                          */
1970
1971                         *buf_size = sizeof(sh) + item_len;
1972                         item_len = 0;
1973                         ret = -EOVERFLOW;
1974                 }
1975
1976                 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
1977                         ret = 1;
1978                         goto out;
1979                 }
1980
1981                 sh.objectid = key->objectid;
1982                 sh.offset = key->offset;
1983                 sh.type = key->type;
1984                 sh.len = item_len;
1985                 sh.transid = found_transid;
1986
1987                 /* copy search result header */
1988                 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
1989                         ret = -EFAULT;
1990                         goto out;
1991                 }
1992
1993                 *sk_offset += sizeof(sh);
1994
1995                 if (item_len) {
1996                         char __user *up = ubuf + *sk_offset;
1997                         /* copy the item */
1998                         if (read_extent_buffer_to_user(leaf, up,
1999                                                        item_off, item_len)) {
2000                                 ret = -EFAULT;
2001                                 goto out;
2002                         }
2003
2004                         *sk_offset += item_len;
2005                 }
2006                 (*num_found)++;
2007
2008                 if (ret) /* -EOVERFLOW from above */
2009                         goto out;
2010
2011                 if (*num_found >= sk->nr_items) {
2012                         ret = 1;
2013                         goto out;
2014                 }
2015         }
2016 advance_key:
2017         ret = 0;
2018         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2019                 key->offset++;
2020         else if (key->type < (u8)-1 && key->type < sk->max_type) {
2021                 key->offset = 0;
2022                 key->type++;
2023         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2024                 key->offset = 0;
2025                 key->type = 0;
2026                 key->objectid++;
2027         } else
2028                 ret = 1;
2029 out:
2030         /*
2031          *  0: all items from this leaf copied, continue with next
2032          *  1: * more items can be copied, but unused buffer is too small
2033          *     * all items were found
2034          *     Either way, it will stops the loop which iterates to the next
2035          *     leaf
2036          *  -EOVERFLOW: item was to large for buffer
2037          *  -EFAULT: could not copy extent buffer back to userspace
2038          */
2039         return ret;
2040 }
2041
2042 static noinline int search_ioctl(struct inode *inode,
2043                                  struct btrfs_ioctl_search_key *sk,
2044                                  size_t *buf_size,
2045                                  char __user *ubuf)
2046 {
2047         struct btrfs_root *root;
2048         struct btrfs_key key;
2049         struct btrfs_path *path;
2050         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2051         int ret;
2052         int num_found = 0;
2053         unsigned long sk_offset = 0;
2054
2055         if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2056                 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2057                 return -EOVERFLOW;
2058         }
2059
2060         path = btrfs_alloc_path();
2061         if (!path)
2062                 return -ENOMEM;
2063
2064         if (sk->tree_id == 0) {
2065                 /* search the root of the inode that was passed */
2066                 root = BTRFS_I(inode)->root;
2067         } else {
2068                 key.objectid = sk->tree_id;
2069                 key.type = BTRFS_ROOT_ITEM_KEY;
2070                 key.offset = (u64)-1;
2071                 root = btrfs_read_fs_root_no_name(info, &key);
2072                 if (IS_ERR(root)) {
2073                         printk(KERN_ERR "BTRFS: could not find root %llu\n",
2074                                sk->tree_id);
2075                         btrfs_free_path(path);
2076                         return -ENOENT;
2077                 }
2078         }
2079
2080         key.objectid = sk->min_objectid;
2081         key.type = sk->min_type;
2082         key.offset = sk->min_offset;
2083
2084         while (1) {
2085                 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2086                 if (ret != 0) {
2087                         if (ret > 0)
2088                                 ret = 0;
2089                         goto err;
2090                 }
2091                 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2092                                  &sk_offset, &num_found);
2093                 btrfs_release_path(path);
2094                 if (ret)
2095                         break;
2096
2097         }
2098         if (ret > 0)
2099                 ret = 0;
2100 err:
2101         sk->nr_items = num_found;
2102         btrfs_free_path(path);
2103         return ret;
2104 }
2105
2106 static noinline int btrfs_ioctl_tree_search(struct file *file,
2107                                            void __user *argp)
2108 {
2109         struct btrfs_ioctl_search_args __user *uargs;
2110         struct btrfs_ioctl_search_key sk;
2111         struct inode *inode;
2112         int ret;
2113         size_t buf_size;
2114
2115         if (!capable(CAP_SYS_ADMIN))
2116                 return -EPERM;
2117
2118         uargs = (struct btrfs_ioctl_search_args __user *)argp;
2119
2120         if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2121                 return -EFAULT;
2122
2123         buf_size = sizeof(uargs->buf);
2124
2125         inode = file_inode(file);
2126         ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2127
2128         /*
2129          * In the origin implementation an overflow is handled by returning a
2130          * search header with a len of zero, so reset ret.
2131          */
2132         if (ret == -EOVERFLOW)
2133                 ret = 0;
2134
2135         if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2136                 ret = -EFAULT;
2137         return ret;
2138 }
2139
2140 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2141                                                void __user *argp)
2142 {
2143         struct btrfs_ioctl_search_args_v2 __user *uarg;
2144         struct btrfs_ioctl_search_args_v2 args;
2145         struct inode *inode;
2146         int ret;
2147         size_t buf_size;
2148         const size_t buf_limit = 16 * 1024 * 1024;
2149
2150         if (!capable(CAP_SYS_ADMIN))
2151                 return -EPERM;
2152
2153         /* copy search header and buffer size */
2154         uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2155         if (copy_from_user(&args, uarg, sizeof(args)))
2156                 return -EFAULT;
2157
2158         buf_size = args.buf_size;
2159
2160         if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2161                 return -EOVERFLOW;
2162
2163         /* limit result size to 16MB */
2164         if (buf_size > buf_limit)
2165                 buf_size = buf_limit;
2166
2167         inode = file_inode(file);
2168         ret = search_ioctl(inode, &args.key, &buf_size,
2169                            (char *)(&uarg->buf[0]));
2170         if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2171                 ret = -EFAULT;
2172         else if (ret == -EOVERFLOW &&
2173                 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2174                 ret = -EFAULT;
2175
2176         return ret;
2177 }
2178
2179 /*
2180  * Search INODE_REFs to identify path name of 'dirid' directory
2181  * in a 'tree_id' tree. and sets path name to 'name'.
2182  */
2183 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2184                                 u64 tree_id, u64 dirid, char *name)
2185 {
2186         struct btrfs_root *root;
2187         struct btrfs_key key;
2188         char *ptr;
2189         int ret = -1;
2190         int slot;
2191         int len;
2192         int total_len = 0;
2193         struct btrfs_inode_ref *iref;
2194         struct extent_buffer *l;
2195         struct btrfs_path *path;
2196
2197         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2198                 name[0]='\0';
2199                 return 0;
2200         }
2201
2202         path = btrfs_alloc_path();
2203         if (!path)
2204                 return -ENOMEM;
2205
2206         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2207
2208         key.objectid = tree_id;
2209         key.type = BTRFS_ROOT_ITEM_KEY;
2210         key.offset = (u64)-1;
2211         root = btrfs_read_fs_root_no_name(info, &key);
2212         if (IS_ERR(root)) {
2213                 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2214                 ret = -ENOENT;
2215                 goto out;
2216         }
2217
2218         key.objectid = dirid;
2219         key.type = BTRFS_INODE_REF_KEY;
2220         key.offset = (u64)-1;
2221
2222         while (1) {
2223                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2224                 if (ret < 0)
2225                         goto out;
2226                 else if (ret > 0) {
2227                         ret = btrfs_previous_item(root, path, dirid,
2228                                                   BTRFS_INODE_REF_KEY);
2229                         if (ret < 0)
2230                                 goto out;
2231                         else if (ret > 0) {
2232                                 ret = -ENOENT;
2233                                 goto out;
2234                         }
2235                 }
2236
2237                 l = path->nodes[0];
2238                 slot = path->slots[0];
2239                 btrfs_item_key_to_cpu(l, &key, slot);
2240
2241                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2242                 len = btrfs_inode_ref_name_len(l, iref);
2243                 ptr -= len + 1;
2244                 total_len += len + 1;
2245                 if (ptr < name) {
2246                         ret = -ENAMETOOLONG;
2247                         goto out;
2248                 }
2249
2250                 *(ptr + len) = '/';
2251                 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2252
2253                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2254                         break;
2255
2256                 btrfs_release_path(path);
2257                 key.objectid = key.offset;
2258                 key.offset = (u64)-1;
2259                 dirid = key.objectid;
2260         }
2261         memmove(name, ptr, total_len);
2262         name[total_len] = '\0';
2263         ret = 0;
2264 out:
2265         btrfs_free_path(path);
2266         return ret;
2267 }
2268
2269 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2270                                            void __user *argp)
2271 {
2272          struct btrfs_ioctl_ino_lookup_args *args;
2273          struct inode *inode;
2274         int ret = 0;
2275
2276         args = memdup_user(argp, sizeof(*args));
2277         if (IS_ERR(args))
2278                 return PTR_ERR(args);
2279
2280         inode = file_inode(file);
2281
2282         /*
2283          * Unprivileged query to obtain the containing subvolume root id. The
2284          * path is reset so it's consistent with btrfs_search_path_in_tree.
2285          */
2286         if (args->treeid == 0)
2287                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2288
2289         if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2290                 args->name[0] = 0;
2291                 goto out;
2292         }
2293
2294         if (!capable(CAP_SYS_ADMIN)) {
2295                 ret = -EPERM;
2296                 goto out;
2297         }
2298
2299         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2300                                         args->treeid, args->objectid,
2301                                         args->name);
2302
2303 out:
2304         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2305                 ret = -EFAULT;
2306
2307         kfree(args);
2308         return ret;
2309 }
2310
2311 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2312                                              void __user *arg)
2313 {
2314         struct dentry *parent = file->f_path.dentry;
2315         struct dentry *dentry;
2316         struct inode *dir = d_inode(parent);
2317         struct inode *inode;
2318         struct btrfs_root *root = BTRFS_I(dir)->root;
2319         struct btrfs_root *dest = NULL;
2320         struct btrfs_ioctl_vol_args *vol_args;
2321         struct btrfs_trans_handle *trans;
2322         struct btrfs_block_rsv block_rsv;
2323         u64 root_flags;
2324         u64 qgroup_reserved;
2325         int namelen;
2326         int ret;
2327         int err = 0;
2328
2329         vol_args = memdup_user(arg, sizeof(*vol_args));
2330         if (IS_ERR(vol_args))
2331                 return PTR_ERR(vol_args);
2332
2333         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2334         namelen = strlen(vol_args->name);
2335         if (strchr(vol_args->name, '/') ||
2336             strncmp(vol_args->name, "..", namelen) == 0) {
2337                 err = -EINVAL;
2338                 goto out;
2339         }
2340
2341         err = mnt_want_write_file(file);
2342         if (err)
2343                 goto out;
2344
2345
2346         err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2347         if (err == -EINTR)
2348                 goto out_drop_write;
2349         dentry = lookup_one_len(vol_args->name, parent, namelen);
2350         if (IS_ERR(dentry)) {
2351                 err = PTR_ERR(dentry);
2352                 goto out_unlock_dir;
2353         }
2354
2355         if (d_really_is_negative(dentry)) {
2356                 err = -ENOENT;
2357                 goto out_dput;
2358         }
2359
2360         inode = d_inode(dentry);
2361         dest = BTRFS_I(inode)->root;
2362         if (!capable(CAP_SYS_ADMIN)) {
2363                 /*
2364                  * Regular user.  Only allow this with a special mount
2365                  * option, when the user has write+exec access to the
2366                  * subvol root, and when rmdir(2) would have been
2367                  * allowed.
2368                  *
2369                  * Note that this is _not_ check that the subvol is
2370                  * empty or doesn't contain data that we wouldn't
2371                  * otherwise be able to delete.
2372                  *
2373                  * Users who want to delete empty subvols should try
2374                  * rmdir(2).
2375                  */
2376                 err = -EPERM;
2377                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2378                         goto out_dput;
2379
2380                 /*
2381                  * Do not allow deletion if the parent dir is the same
2382                  * as the dir to be deleted.  That means the ioctl
2383                  * must be called on the dentry referencing the root
2384                  * of the subvol, not a random directory contained
2385                  * within it.
2386                  */
2387                 err = -EINVAL;
2388                 if (root == dest)
2389                         goto out_dput;
2390
2391                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2392                 if (err)
2393                         goto out_dput;
2394         }
2395
2396         /* check if subvolume may be deleted by a user */
2397         err = btrfs_may_delete(dir, dentry, 1);
2398         if (err)
2399                 goto out_dput;
2400
2401         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2402                 err = -EINVAL;
2403                 goto out_dput;
2404         }
2405
2406         mutex_lock(&inode->i_mutex);
2407
2408         /*
2409          * Don't allow to delete a subvolume with send in progress. This is
2410          * inside the i_mutex so the error handling that has to drop the bit
2411          * again is not run concurrently.
2412          */
2413         spin_lock(&dest->root_item_lock);
2414         root_flags = btrfs_root_flags(&dest->root_item);
2415         if (dest->send_in_progress == 0) {
2416                 btrfs_set_root_flags(&dest->root_item,
2417                                 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2418                 spin_unlock(&dest->root_item_lock);
2419         } else {
2420                 spin_unlock(&dest->root_item_lock);
2421                 btrfs_warn(root->fs_info,
2422                         "Attempt to delete subvolume %llu during send",
2423                         dest->root_key.objectid);
2424                 err = -EPERM;
2425                 goto out_unlock_inode;
2426         }
2427
2428         down_write(&root->fs_info->subvol_sem);
2429
2430         err = may_destroy_subvol(dest);
2431         if (err)
2432                 goto out_up_write;
2433
2434         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2435         /*
2436          * One for dir inode, two for dir entries, two for root
2437          * ref/backref.
2438          */
2439         err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2440                                                5, &qgroup_reserved, true);
2441         if (err)
2442                 goto out_up_write;
2443
2444         trans = btrfs_start_transaction(root, 0);
2445         if (IS_ERR(trans)) {
2446                 err = PTR_ERR(trans);
2447                 goto out_release;
2448         }
2449         trans->block_rsv = &block_rsv;
2450         trans->bytes_reserved = block_rsv.size;
2451
2452         ret = btrfs_unlink_subvol(trans, root, dir,
2453                                 dest->root_key.objectid,
2454                                 dentry->d_name.name,
2455                                 dentry->d_name.len);
2456         if (ret) {
2457                 err = ret;
2458                 btrfs_abort_transaction(trans, root, ret);
2459                 goto out_end_trans;
2460         }
2461
2462         btrfs_record_root_in_trans(trans, dest);
2463
2464         memset(&dest->root_item.drop_progress, 0,
2465                 sizeof(dest->root_item.drop_progress));
2466         dest->root_item.drop_level = 0;
2467         btrfs_set_root_refs(&dest->root_item, 0);
2468
2469         if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2470                 ret = btrfs_insert_orphan_item(trans,
2471                                         root->fs_info->tree_root,
2472                                         dest->root_key.objectid);
2473                 if (ret) {
2474                         btrfs_abort_transaction(trans, root, ret);
2475                         err = ret;
2476                         goto out_end_trans;
2477                 }
2478         }
2479
2480         ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2481                                   dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2482                                   dest->root_key.objectid);
2483         if (ret && ret != -ENOENT) {
2484                 btrfs_abort_transaction(trans, root, ret);
2485                 err = ret;
2486                 goto out_end_trans;
2487         }
2488         if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2489                 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2490                                           dest->root_item.received_uuid,
2491                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2492                                           dest->root_key.objectid);
2493                 if (ret && ret != -ENOENT) {
2494                         btrfs_abort_transaction(trans, root, ret);
2495                         err = ret;
2496                         goto out_end_trans;
2497                 }
2498         }
2499
2500 out_end_trans:
2501         trans->block_rsv = NULL;
2502         trans->bytes_reserved = 0;
2503         ret = btrfs_end_transaction(trans, root);
2504         if (ret && !err)
2505                 err = ret;
2506         inode->i_flags |= S_DEAD;
2507 out_release:
2508         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2509 out_up_write:
2510         up_write(&root->fs_info->subvol_sem);
2511         if (err) {
2512                 spin_lock(&dest->root_item_lock);
2513                 root_flags = btrfs_root_flags(&dest->root_item);
2514                 btrfs_set_root_flags(&dest->root_item,
2515                                 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2516                 spin_unlock(&dest->root_item_lock);
2517         }
2518 out_unlock_inode:
2519         mutex_unlock(&inode->i_mutex);
2520         if (!err) {
2521                 d_invalidate(dentry);
2522                 btrfs_invalidate_inodes(dest);
2523                 d_delete(dentry);
2524                 ASSERT(dest->send_in_progress == 0);
2525
2526                 /* the last ref */
2527                 if (dest->ino_cache_inode) {
2528                         iput(dest->ino_cache_inode);
2529                         dest->ino_cache_inode = NULL;
2530                 }
2531         }
2532 out_dput:
2533         dput(dentry);
2534 out_unlock_dir:
2535         mutex_unlock(&dir->i_mutex);
2536 out_drop_write:
2537         mnt_drop_write_file(file);
2538 out:
2539         kfree(vol_args);
2540         return err;
2541 }
2542
2543 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2544 {
2545         struct inode *inode = file_inode(file);
2546         struct btrfs_root *root = BTRFS_I(inode)->root;
2547         struct btrfs_ioctl_defrag_range_args *range;
2548         int ret;
2549
2550         ret = mnt_want_write_file(file);
2551         if (ret)
2552                 return ret;
2553
2554         if (btrfs_root_readonly(root)) {
2555                 ret = -EROFS;
2556                 goto out;
2557         }
2558
2559         switch (inode->i_mode & S_IFMT) {
2560         case S_IFDIR:
2561                 if (!capable(CAP_SYS_ADMIN)) {
2562                         ret = -EPERM;
2563                         goto out;
2564                 }
2565                 ret = btrfs_defrag_root(root);
2566                 if (ret)
2567                         goto out;
2568                 ret = btrfs_defrag_root(root->fs_info->extent_root);
2569                 break;
2570         case S_IFREG:
2571                 if (!(file->f_mode & FMODE_WRITE)) {
2572                         ret = -EINVAL;
2573                         goto out;
2574                 }
2575
2576                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2577                 if (!range) {
2578                         ret = -ENOMEM;
2579                         goto out;
2580                 }
2581
2582                 if (argp) {
2583                         if (copy_from_user(range, argp,
2584                                            sizeof(*range))) {
2585                                 ret = -EFAULT;
2586                                 kfree(range);
2587                                 goto out;
2588                         }
2589                         /* compression requires us to start the IO */
2590                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2591                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2592                                 range->extent_thresh = (u32)-1;
2593                         }
2594                 } else {
2595                         /* the rest are all set to zero by kzalloc */
2596                         range->len = (u64)-1;
2597                 }
2598                 ret = btrfs_defrag_file(file_inode(file), file,
2599                                         range, 0, 0);
2600                 if (ret > 0)
2601                         ret = 0;
2602                 kfree(range);
2603                 break;
2604         default:
2605                 ret = -EINVAL;
2606         }
2607 out:
2608         mnt_drop_write_file(file);
2609         return ret;
2610 }
2611
2612 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2613 {
2614         struct btrfs_ioctl_vol_args *vol_args;
2615         int ret;
2616
2617         if (!capable(CAP_SYS_ADMIN))
2618                 return -EPERM;
2619
2620         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2621                         1)) {
2622                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2623         }
2624
2625         mutex_lock(&root->fs_info->volume_mutex);
2626         vol_args = memdup_user(arg, sizeof(*vol_args));
2627         if (IS_ERR(vol_args)) {
2628                 ret = PTR_ERR(vol_args);
2629                 goto out;
2630         }
2631
2632         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2633         ret = btrfs_init_new_device(root, vol_args->name);
2634
2635         if (!ret)
2636                 btrfs_info(root->fs_info, "disk added %s",vol_args->name);
2637
2638         kfree(vol_args);
2639 out:
2640         mutex_unlock(&root->fs_info->volume_mutex);
2641         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2642         return ret;
2643 }
2644
2645 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2646 {
2647         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2648         struct btrfs_ioctl_vol_args *vol_args;
2649         int ret;
2650
2651         if (!capable(CAP_SYS_ADMIN))
2652                 return -EPERM;
2653
2654         ret = mnt_want_write_file(file);
2655         if (ret)
2656                 return ret;
2657
2658         vol_args = memdup_user(arg, sizeof(*vol_args));
2659         if (IS_ERR(vol_args)) {
2660                 ret = PTR_ERR(vol_args);
2661                 goto err_drop;
2662         }
2663
2664         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2665
2666         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2667                         1)) {
2668                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2669                 goto out;
2670         }
2671
2672         mutex_lock(&root->fs_info->volume_mutex);
2673         ret = btrfs_rm_device(root, vol_args->name);
2674         mutex_unlock(&root->fs_info->volume_mutex);
2675         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2676
2677         if (!ret)
2678                 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
2679
2680 out:
2681         kfree(vol_args);
2682 err_drop:
2683         mnt_drop_write_file(file);
2684         return ret;
2685 }
2686
2687 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2688 {
2689         struct btrfs_ioctl_fs_info_args *fi_args;
2690         struct btrfs_device *device;
2691         struct btrfs_device *next;
2692         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2693         int ret = 0;
2694
2695         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2696         if (!fi_args)
2697                 return -ENOMEM;
2698
2699         mutex_lock(&fs_devices->device_list_mutex);
2700         fi_args->num_devices = fs_devices->num_devices;
2701         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2702
2703         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2704                 if (device->devid > fi_args->max_id)
2705                         fi_args->max_id = device->devid;
2706         }
2707         mutex_unlock(&fs_devices->device_list_mutex);
2708
2709         fi_args->nodesize = root->fs_info->super_copy->nodesize;
2710         fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2711         fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2712
2713         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2714                 ret = -EFAULT;
2715
2716         kfree(fi_args);
2717         return ret;
2718 }
2719
2720 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2721 {
2722         struct btrfs_ioctl_dev_info_args *di_args;
2723         struct btrfs_device *dev;
2724         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2725         int ret = 0;
2726         char *s_uuid = NULL;
2727
2728         di_args = memdup_user(arg, sizeof(*di_args));
2729         if (IS_ERR(di_args))
2730                 return PTR_ERR(di_args);
2731
2732         if (!btrfs_is_empty_uuid(di_args->uuid))
2733                 s_uuid = di_args->uuid;
2734
2735         mutex_lock(&fs_devices->device_list_mutex);
2736         dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2737
2738         if (!dev) {
2739                 ret = -ENODEV;
2740                 goto out;
2741         }
2742
2743         di_args->devid = dev->devid;
2744         di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2745         di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2746         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2747         if (dev->name) {
2748                 struct rcu_string *name;
2749
2750                 rcu_read_lock();
2751                 name = rcu_dereference(dev->name);
2752                 strncpy(di_args->path, name->str, sizeof(di_args->path));
2753                 rcu_read_unlock();
2754                 di_args->path[sizeof(di_args->path) - 1] = 0;
2755         } else {
2756                 di_args->path[0] = '\0';
2757         }
2758
2759 out:
2760         mutex_unlock(&fs_devices->device_list_mutex);
2761         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2762                 ret = -EFAULT;
2763
2764         kfree(di_args);
2765         return ret;
2766 }
2767
2768 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2769 {
2770         struct page *page;
2771         pgoff_t index;
2772         struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2773
2774         index = off >> PAGE_CACHE_SHIFT;
2775
2776         page = grab_cache_page(inode->i_mapping, index);
2777         if (!page)
2778                 return NULL;
2779
2780         if (!PageUptodate(page)) {
2781                 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2782                                                  0))
2783                         return NULL;
2784                 lock_page(page);
2785                 if (!PageUptodate(page)) {
2786                         unlock_page(page);
2787                         page_cache_release(page);
2788                         return NULL;
2789                 }
2790         }
2791         unlock_page(page);
2792
2793         return page;
2794 }
2795
2796 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2797 {
2798         /* do any pending delalloc/csum calc on src, one way or
2799            another, and lock file content */
2800         while (1) {
2801                 struct btrfs_ordered_extent *ordered;
2802                 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2803                 ordered = btrfs_lookup_first_ordered_extent(inode,
2804                                                             off + len - 1);
2805                 if ((!ordered ||
2806                      ordered->file_offset + ordered->len <= off ||
2807                      ordered->file_offset >= off + len) &&
2808                     !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2809                                     off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2810                         if (ordered)
2811                                 btrfs_put_ordered_extent(ordered);
2812                         break;
2813                 }
2814                 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2815                 if (ordered)
2816                         btrfs_put_ordered_extent(ordered);
2817                 btrfs_wait_ordered_range(inode, off, len);
2818         }
2819 }
2820
2821 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2822                                 struct inode *inode2, u64 loff2, u64 len)
2823 {
2824         unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2825         unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2826
2827         mutex_unlock(&inode1->i_mutex);
2828         mutex_unlock(&inode2->i_mutex);
2829 }
2830
2831 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2832                               struct inode *inode2, u64 loff2, u64 len)
2833 {
2834         if (inode1 < inode2) {
2835                 swap(inode1, inode2);
2836                 swap(loff1, loff2);
2837         }
2838
2839         mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2840         lock_extent_range(inode1, loff1, len);
2841         if (inode1 != inode2) {
2842                 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2843                 lock_extent_range(inode2, loff2, len);
2844         }
2845 }
2846
2847 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2848                           u64 dst_loff, u64 len)
2849 {
2850         int ret = 0;
2851         struct page *src_page, *dst_page;
2852         unsigned int cmp_len = PAGE_CACHE_SIZE;
2853         void *addr, *dst_addr;
2854
2855         while (len) {
2856                 if (len < PAGE_CACHE_SIZE)
2857                         cmp_len = len;
2858
2859                 src_page = extent_same_get_page(src, loff);
2860                 if (!src_page)
2861                         return -EINVAL;
2862                 dst_page = extent_same_get_page(dst, dst_loff);
2863                 if (!dst_page) {
2864                         page_cache_release(src_page);
2865                         return -EINVAL;
2866                 }
2867                 addr = kmap_atomic(src_page);
2868                 dst_addr = kmap_atomic(dst_page);
2869
2870                 flush_dcache_page(src_page);
2871                 flush_dcache_page(dst_page);
2872
2873                 if (memcmp(addr, dst_addr, cmp_len))
2874                         ret = BTRFS_SAME_DATA_DIFFERS;
2875
2876                 kunmap_atomic(addr);
2877                 kunmap_atomic(dst_addr);
2878                 page_cache_release(src_page);
2879                 page_cache_release(dst_page);
2880
2881                 if (ret)
2882                         break;
2883
2884                 loff += cmp_len;
2885                 dst_loff += cmp_len;
2886                 len -= cmp_len;
2887         }
2888
2889         return ret;
2890 }
2891
2892 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 *plen,
2893                                      u64 olen)
2894 {
2895         u64 len = *plen;
2896         u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2897
2898         if (off + olen > inode->i_size || off + olen < off)
2899                 return -EINVAL;
2900
2901         /* if we extend to eof, continue to block boundary */
2902         if (off + len == inode->i_size)
2903                 *plen = len = ALIGN(inode->i_size, bs) - off;
2904
2905         /* Check that we are block aligned - btrfs_clone() requires this */
2906         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2907                 return -EINVAL;
2908
2909         return 0;
2910 }
2911
2912 static int btrfs_extent_same(struct inode *src, u64 loff, u64 olen,
2913                              struct inode *dst, u64 dst_loff)
2914 {
2915         int ret;
2916         u64 len = olen;
2917
2918         /*
2919          * btrfs_clone() can't handle extents in the same file
2920          * yet. Once that works, we can drop this check and replace it
2921          * with a check for the same inode, but overlapping extents.
2922          */
2923         if (src == dst)
2924                 return -EINVAL;
2925
2926         if (len == 0)
2927                 return 0;
2928
2929         btrfs_double_lock(src, loff, dst, dst_loff, len);
2930
2931         ret = extent_same_check_offsets(src, loff, &len, olen);
2932         if (ret)
2933                 goto out_unlock;
2934
2935         ret = extent_same_check_offsets(dst, dst_loff, &len, olen);
2936         if (ret)
2937                 goto out_unlock;
2938
2939         /* don't make the dst file partly checksummed */
2940         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2941             (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2942                 ret = -EINVAL;
2943                 goto out_unlock;
2944         }
2945
2946         ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2947         if (ret == 0)
2948                 ret = btrfs_clone(src, dst, loff, olen, len, dst_loff);
2949
2950 out_unlock:
2951         btrfs_double_unlock(src, loff, dst, dst_loff, len);
2952
2953         return ret;
2954 }
2955
2956 #define BTRFS_MAX_DEDUPE_LEN    (16 * 1024 * 1024)
2957
2958 static long btrfs_ioctl_file_extent_same(struct file *file,
2959                         struct btrfs_ioctl_same_args __user *argp)
2960 {
2961         struct btrfs_ioctl_same_args *same;
2962         struct btrfs_ioctl_same_extent_info *info;
2963         struct inode *src = file_inode(file);
2964         u64 off;
2965         u64 len;
2966         int i;
2967         int ret;
2968         unsigned long size;
2969         u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2970         bool is_admin = capable(CAP_SYS_ADMIN);
2971         u16 count;
2972
2973         if (!(file->f_mode & FMODE_READ))
2974                 return -EINVAL;
2975
2976         ret = mnt_want_write_file(file);
2977         if (ret)
2978                 return ret;
2979
2980         if (get_user(count, &argp->dest_count)) {
2981                 ret = -EFAULT;
2982                 goto out;
2983         }
2984
2985         size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2986
2987         same = memdup_user(argp, size);
2988
2989         if (IS_ERR(same)) {
2990                 ret = PTR_ERR(same);
2991                 goto out;
2992         }
2993
2994         off = same->logical_offset;
2995         len = same->length;
2996
2997         /*
2998          * Limit the total length we will dedupe for each operation.
2999          * This is intended to bound the total time spent in this
3000          * ioctl to something sane.
3001          */
3002         if (len > BTRFS_MAX_DEDUPE_LEN)
3003                 len = BTRFS_MAX_DEDUPE_LEN;
3004
3005         if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
3006                 /*
3007                  * Btrfs does not support blocksize < page_size. As a
3008                  * result, btrfs_cmp_data() won't correctly handle
3009                  * this situation without an update.
3010                  */
3011                 ret = -EINVAL;
3012                 goto out;
3013         }
3014
3015         ret = -EISDIR;
3016         if (S_ISDIR(src->i_mode))
3017                 goto out;
3018
3019         ret = -EACCES;
3020         if (!S_ISREG(src->i_mode))
3021                 goto out;
3022
3023         /* pre-format output fields to sane values */
3024         for (i = 0; i < count; i++) {
3025                 same->info[i].bytes_deduped = 0ULL;
3026                 same->info[i].status = 0;
3027         }
3028
3029         for (i = 0, info = same->info; i < count; i++, info++) {
3030                 struct inode *dst;
3031                 struct fd dst_file = fdget(info->fd);
3032                 if (!dst_file.file) {
3033                         info->status = -EBADF;
3034                         continue;
3035                 }
3036                 dst = file_inode(dst_file.file);
3037
3038                 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3039                         info->status = -EINVAL;
3040                 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3041                         info->status = -EXDEV;
3042                 } else if (S_ISDIR(dst->i_mode)) {
3043                         info->status = -EISDIR;
3044                 } else if (!S_ISREG(dst->i_mode)) {
3045                         info->status = -EACCES;
3046                 } else {
3047                         info->status = btrfs_extent_same(src, off, len, dst,
3048                                                         info->logical_offset);
3049                         if (info->status == 0)
3050                                 info->bytes_deduped += len;
3051                 }
3052                 fdput(dst_file);
3053         }
3054
3055         ret = copy_to_user(argp, same, size);
3056         if (ret)
3057                 ret = -EFAULT;
3058
3059 out:
3060         mnt_drop_write_file(file);
3061         return ret;
3062 }
3063
3064 /* Helper to check and see if this root currently has a ref on the given disk
3065  * bytenr.  If it does then we need to update the quota for this root.  This
3066  * doesn't do anything if quotas aren't enabled.
3067  */
3068 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3069                      u64 disko)
3070 {
3071         struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
3072         struct ulist *roots;
3073         struct ulist_iterator uiter;
3074         struct ulist_node *root_node = NULL;
3075         int ret;
3076
3077         if (!root->fs_info->quota_enabled)
3078                 return 1;
3079
3080         btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3081         ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3082                                    tree_mod_seq_elem.seq, &roots);
3083         if (ret < 0)
3084                 goto out;
3085         ret = 0;
3086         ULIST_ITER_INIT(&uiter);
3087         while ((root_node = ulist_next(roots, &uiter))) {
3088                 if (root_node->val == root->objectid) {
3089                         ret = 1;
3090                         break;
3091                 }
3092         }
3093         ulist_free(roots);
3094 out:
3095         btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3096         return ret;
3097 }
3098
3099 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3100                                      struct inode *inode,
3101                                      u64 endoff,
3102                                      const u64 destoff,
3103                                      const u64 olen)
3104 {
3105         struct btrfs_root *root = BTRFS_I(inode)->root;
3106         int ret;
3107
3108         inode_inc_iversion(inode);
3109         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3110         /*
3111          * We round up to the block size at eof when determining which
3112          * extents to clone above, but shouldn't round up the file size.
3113          */
3114         if (endoff > destoff + olen)
3115                 endoff = destoff + olen;
3116         if (endoff > inode->i_size)
3117                 btrfs_i_size_write(inode, endoff);
3118
3119         ret = btrfs_update_inode(trans, root, inode);
3120         if (ret) {
3121                 btrfs_abort_transaction(trans, root, ret);
3122                 btrfs_end_transaction(trans, root);
3123                 goto out;
3124         }
3125         ret = btrfs_end_transaction(trans, root);
3126 out:
3127         return ret;
3128 }
3129
3130 static void clone_update_extent_map(struct inode *inode,
3131                                     const struct btrfs_trans_handle *trans,
3132                                     const struct btrfs_path *path,
3133                                     const u64 hole_offset,
3134                                     const u64 hole_len)
3135 {
3136         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3137         struct extent_map *em;
3138         int ret;
3139
3140         em = alloc_extent_map();
3141         if (!em) {
3142                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3143                         &BTRFS_I(inode)->runtime_flags);
3144                 return;
3145         }
3146
3147         if (path) {
3148                 struct btrfs_file_extent_item *fi;
3149
3150                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3151                                     struct btrfs_file_extent_item);
3152                 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3153                 em->generation = -1;
3154                 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3155                     BTRFS_FILE_EXTENT_INLINE)
3156                         set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3157                                 &BTRFS_I(inode)->runtime_flags);
3158         } else {
3159                 em->start = hole_offset;
3160                 em->len = hole_len;
3161                 em->ram_bytes = em->len;
3162                 em->orig_start = hole_offset;
3163                 em->block_start = EXTENT_MAP_HOLE;
3164                 em->block_len = 0;
3165                 em->orig_block_len = 0;
3166                 em->compress_type = BTRFS_COMPRESS_NONE;
3167                 em->generation = trans->transid;
3168         }
3169
3170         while (1) {
3171                 write_lock(&em_tree->lock);
3172                 ret = add_extent_mapping(em_tree, em, 1);
3173                 write_unlock(&em_tree->lock);
3174                 if (ret != -EEXIST) {
3175                         free_extent_map(em);
3176                         break;
3177                 }
3178                 btrfs_drop_extent_cache(inode, em->start,
3179                                         em->start + em->len - 1, 0);
3180         }
3181
3182         if (ret)
3183                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3184                         &BTRFS_I(inode)->runtime_flags);
3185 }
3186
3187 /**
3188  * btrfs_clone() - clone a range from inode file to another
3189  *
3190  * @src: Inode to clone from
3191  * @inode: Inode to clone to
3192  * @off: Offset within source to start clone from
3193  * @olen: Original length, passed by user, of range to clone
3194  * @olen_aligned: Block-aligned value of olen, extent_same uses
3195  *               identical values here
3196  * @destoff: Offset within @inode to start clone
3197  */
3198 static int btrfs_clone(struct inode *src, struct inode *inode,
3199                        const u64 off, const u64 olen, const u64 olen_aligned,
3200                        const u64 destoff)
3201 {
3202         struct btrfs_root *root = BTRFS_I(inode)->root;
3203         struct btrfs_path *path = NULL;
3204         struct extent_buffer *leaf;
3205         struct btrfs_trans_handle *trans;
3206         char *buf = NULL;
3207         struct btrfs_key key;
3208         u32 nritems;
3209         int slot;
3210         int ret;
3211         int no_quota;
3212         const u64 len = olen_aligned;
3213         u64 last_disko = 0;
3214         u64 last_dest_end = destoff;
3215
3216         ret = -ENOMEM;
3217         buf = vmalloc(root->nodesize);
3218         if (!buf)
3219                 return ret;
3220
3221         path = btrfs_alloc_path();
3222         if (!path) {
3223                 vfree(buf);
3224                 return ret;
3225         }
3226
3227         path->reada = 2;
3228         /* clone data */
3229         key.objectid = btrfs_ino(src);
3230         key.type = BTRFS_EXTENT_DATA_KEY;
3231         key.offset = off;
3232
3233         while (1) {
3234                 u64 next_key_min_offset = key.offset + 1;
3235
3236                 /*
3237                  * note the key will change type as we walk through the
3238                  * tree.
3239                  */
3240                 path->leave_spinning = 1;
3241                 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3242                                 0, 0);
3243                 if (ret < 0)
3244                         goto out;
3245                 /*
3246                  * First search, if no extent item that starts at offset off was
3247                  * found but the previous item is an extent item, it's possible
3248                  * it might overlap our target range, therefore process it.
3249                  */
3250                 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3251                         btrfs_item_key_to_cpu(path->nodes[0], &key,
3252                                               path->slots[0] - 1);
3253                         if (key.type == BTRFS_EXTENT_DATA_KEY)
3254                                 path->slots[0]--;
3255                 }
3256
3257                 nritems = btrfs_header_nritems(path->nodes[0]);
3258 process_slot:
3259                 no_quota = 1;
3260                 if (path->slots[0] >= nritems) {
3261                         ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3262                         if (ret < 0)
3263                                 goto out;
3264                         if (ret > 0)
3265                                 break;
3266                         nritems = btrfs_header_nritems(path->nodes[0]);
3267                 }
3268                 leaf = path->nodes[0];
3269                 slot = path->slots[0];
3270
3271                 btrfs_item_key_to_cpu(leaf, &key, slot);
3272                 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3273                     key.objectid != btrfs_ino(src))
3274                         break;
3275
3276                 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3277                         struct btrfs_file_extent_item *extent;
3278                         int type;
3279                         u32 size;
3280                         struct btrfs_key new_key;
3281                         u64 disko = 0, diskl = 0;
3282                         u64 datao = 0, datal = 0;
3283                         u8 comp;
3284                         u64 drop_start;
3285
3286                         extent = btrfs_item_ptr(leaf, slot,
3287                                                 struct btrfs_file_extent_item);
3288                         comp = btrfs_file_extent_compression(leaf, extent);
3289                         type = btrfs_file_extent_type(leaf, extent);
3290                         if (type == BTRFS_FILE_EXTENT_REG ||
3291                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3292                                 disko = btrfs_file_extent_disk_bytenr(leaf,
3293                                                                       extent);
3294                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3295                                                                  extent);
3296                                 datao = btrfs_file_extent_offset(leaf, extent);
3297                                 datal = btrfs_file_extent_num_bytes(leaf,
3298                                                                     extent);
3299                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3300                                 /* take upper bound, may be compressed */
3301                                 datal = btrfs_file_extent_ram_bytes(leaf,
3302                                                                     extent);
3303                         }
3304
3305                         /*
3306                          * The first search might have left us at an extent
3307                          * item that ends before our target range's start, can
3308                          * happen if we have holes and NO_HOLES feature enabled.
3309                          */
3310                         if (key.offset + datal <= off) {
3311                                 path->slots[0]++;
3312                                 goto process_slot;
3313                         } else if (key.offset >= off + len) {
3314                                 break;
3315                         }
3316                         next_key_min_offset = key.offset + datal;
3317                         size = btrfs_item_size_nr(leaf, slot);
3318                         read_extent_buffer(leaf, buf,
3319                                            btrfs_item_ptr_offset(leaf, slot),
3320                                            size);
3321
3322                         btrfs_release_path(path);
3323                         path->leave_spinning = 0;
3324
3325                         memcpy(&new_key, &key, sizeof(new_key));
3326                         new_key.objectid = btrfs_ino(inode);
3327                         if (off <= key.offset)
3328                                 new_key.offset = key.offset + destoff - off;
3329                         else
3330                                 new_key.offset = destoff;
3331
3332                         /*
3333                          * Deal with a hole that doesn't have an extent item
3334                          * that represents it (NO_HOLES feature enabled).
3335                          * This hole is either in the middle of the cloning
3336                          * range or at the beginning (fully overlaps it or
3337                          * partially overlaps it).
3338                          */
3339                         if (new_key.offset != last_dest_end)
3340                                 drop_start = last_dest_end;
3341                         else
3342                                 drop_start = new_key.offset;
3343
3344                         /*
3345                          * 1 - adjusting old extent (we may have to split it)
3346                          * 1 - add new extent
3347                          * 1 - inode update
3348                          */
3349                         trans = btrfs_start_transaction(root, 3);
3350                         if (IS_ERR(trans)) {
3351                                 ret = PTR_ERR(trans);
3352                                 goto out;
3353                         }
3354
3355                         if (type == BTRFS_FILE_EXTENT_REG ||
3356                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3357                                 /*
3358                                  *    a  | --- range to clone ---|  b
3359                                  * | ------------- extent ------------- |
3360                                  */
3361
3362                                 /* subtract range b */
3363                                 if (key.offset + datal > off + len)
3364                                         datal = off + len - key.offset;
3365
3366                                 /* subtract range a */
3367                                 if (off > key.offset) {
3368                                         datao += off - key.offset;
3369                                         datal -= off - key.offset;
3370                                 }
3371
3372                                 ret = btrfs_drop_extents(trans, root, inode,
3373                                                          drop_start,
3374                                                          new_key.offset + datal,
3375                                                          1);
3376                                 if (ret) {
3377                                         if (ret != -EOPNOTSUPP)
3378                                                 btrfs_abort_transaction(trans,
3379                                                                 root, ret);
3380                                         btrfs_end_transaction(trans, root);
3381                                         goto out;
3382                                 }
3383
3384                                 ret = btrfs_insert_empty_item(trans, root, path,
3385                                                               &new_key, size);
3386                                 if (ret) {
3387                                         btrfs_abort_transaction(trans, root,
3388                                                                 ret);
3389                                         btrfs_end_transaction(trans, root);
3390                                         goto out;
3391                                 }
3392
3393                                 leaf = path->nodes[0];
3394                                 slot = path->slots[0];
3395                                 write_extent_buffer(leaf, buf,
3396                                             btrfs_item_ptr_offset(leaf, slot),
3397                                             size);
3398
3399                                 extent = btrfs_item_ptr(leaf, slot,
3400                                                 struct btrfs_file_extent_item);
3401
3402                                 /* disko == 0 means it's a hole */
3403                                 if (!disko)
3404                                         datao = 0;
3405
3406                                 btrfs_set_file_extent_offset(leaf, extent,
3407                                                              datao);
3408                                 btrfs_set_file_extent_num_bytes(leaf, extent,
3409                                                                 datal);
3410
3411                                 /*
3412                                  * We need to look up the roots that point at
3413                                  * this bytenr and see if the new root does.  If
3414                                  * it does not we need to make sure we update
3415                                  * quotas appropriately.
3416                                  */
3417                                 if (disko && root != BTRFS_I(src)->root &&
3418                                     disko != last_disko) {
3419                                         no_quota = check_ref(trans, root,
3420                                                              disko);
3421                                         if (no_quota < 0) {
3422                                                 btrfs_abort_transaction(trans,
3423                                                                         root,
3424                                                                         ret);
3425                                                 btrfs_end_transaction(trans,
3426                                                                       root);
3427                                                 ret = no_quota;
3428                                                 goto out;
3429                                         }
3430                                 }
3431
3432                                 if (disko) {
3433                                         inode_add_bytes(inode, datal);
3434                                         ret = btrfs_inc_extent_ref(trans, root,
3435                                                         disko, diskl, 0,
3436                                                         root->root_key.objectid,
3437                                                         btrfs_ino(inode),
3438                                                         new_key.offset - datao,
3439                                                         no_quota);
3440                                         if (ret) {
3441                                                 btrfs_abort_transaction(trans,
3442                                                                         root,
3443                                                                         ret);
3444                                                 btrfs_end_transaction(trans,
3445                                                                       root);
3446                                                 goto out;
3447
3448                                         }
3449                                 }
3450                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3451                                 u64 skip = 0;
3452                                 u64 trim = 0;
3453                                 u64 aligned_end = 0;
3454
3455                                 if (off > key.offset) {
3456                                         skip = off - key.offset;
3457                                         new_key.offset += skip;
3458                                 }
3459
3460                                 if (key.offset + datal > off + len)
3461                                         trim = key.offset + datal - (off + len);
3462
3463                                 if (comp && (skip || trim)) {
3464                                         ret = -EINVAL;
3465                                         btrfs_end_transaction(trans, root);
3466                                         goto out;
3467                                 }
3468                                 size -= skip + trim;
3469                                 datal -= skip + trim;
3470
3471                                 aligned_end = ALIGN(new_key.offset + datal,
3472                                                     root->sectorsize);
3473                                 ret = btrfs_drop_extents(trans, root, inode,
3474                                                          drop_start,
3475                                                          aligned_end,
3476                                                          1);
3477                                 if (ret) {
3478                                         if (ret != -EOPNOTSUPP)
3479                                                 btrfs_abort_transaction(trans,
3480                                                         root, ret);
3481                                         btrfs_end_transaction(trans, root);
3482                                         goto out;
3483                                 }
3484
3485                                 ret = btrfs_insert_empty_item(trans, root, path,
3486                                                               &new_key, size);
3487                                 if (ret) {
3488                                         btrfs_abort_transaction(trans, root,
3489                                                                 ret);
3490                                         btrfs_end_transaction(trans, root);
3491                                         goto out;
3492                                 }
3493
3494                                 if (skip) {
3495                                         u32 start =
3496                                           btrfs_file_extent_calc_inline_size(0);
3497                                         memmove(buf+start, buf+start+skip,
3498                                                 datal);
3499                                 }
3500
3501                                 leaf = path->nodes[0];
3502                                 slot = path->slots[0];
3503                                 write_extent_buffer(leaf, buf,
3504                                             btrfs_item_ptr_offset(leaf, slot),
3505                                             size);
3506                                 inode_add_bytes(inode, datal);
3507                         }
3508
3509                         /* If we have an implicit hole (NO_HOLES feature). */
3510                         if (drop_start < new_key.offset)
3511                                 clone_update_extent_map(inode, trans,
3512                                                 NULL, drop_start,
3513                                                 new_key.offset - drop_start);
3514
3515                         clone_update_extent_map(inode, trans, path, 0, 0);
3516
3517                         btrfs_mark_buffer_dirty(leaf);
3518                         btrfs_release_path(path);
3519
3520                         last_dest_end = ALIGN(new_key.offset + datal,
3521                                               root->sectorsize);
3522                         ret = clone_finish_inode_update(trans, inode,
3523                                                         last_dest_end,
3524                                                         destoff, olen);
3525                         if (ret)
3526                                 goto out;
3527                         if (new_key.offset + datal >= destoff + len)
3528                                 break;
3529                 }
3530                 btrfs_release_path(path);
3531                 key.offset = next_key_min_offset;
3532         }
3533         ret = 0;
3534
3535         if (last_dest_end < destoff + len) {
3536                 /*
3537                  * We have an implicit hole (NO_HOLES feature is enabled) that
3538                  * fully or partially overlaps our cloning range at its end.
3539                  */
3540                 btrfs_release_path(path);
3541
3542                 /*
3543                  * 1 - remove extent(s)
3544                  * 1 - inode update
3545                  */
3546                 trans = btrfs_start_transaction(root, 2);
3547                 if (IS_ERR(trans)) {
3548                         ret = PTR_ERR(trans);
3549                         goto out;
3550                 }
3551                 ret = btrfs_drop_extents(trans, root, inode,
3552                                          last_dest_end, destoff + len, 1);
3553                 if (ret) {
3554                         if (ret != -EOPNOTSUPP)
3555                                 btrfs_abort_transaction(trans, root, ret);
3556                         btrfs_end_transaction(trans, root);
3557                         goto out;
3558                 }
3559                 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3560                                         destoff + len - last_dest_end);
3561                 ret = clone_finish_inode_update(trans, inode, destoff + len,
3562                                                 destoff, olen);
3563         }
3564
3565 out:
3566         btrfs_free_path(path);
3567         vfree(buf);
3568         return ret;
3569 }
3570
3571 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3572                                        u64 off, u64 olen, u64 destoff)
3573 {
3574         struct inode *inode = file_inode(file);
3575         struct btrfs_root *root = BTRFS_I(inode)->root;
3576         struct fd src_file;
3577         struct inode *src;
3578         int ret;
3579         u64 len = olen;
3580         u64 bs = root->fs_info->sb->s_blocksize;
3581         int same_inode = 0;
3582
3583         /*
3584          * TODO:
3585          * - split compressed inline extents.  annoying: we need to
3586          *   decompress into destination's address_space (the file offset
3587          *   may change, so source mapping won't do), then recompress (or
3588          *   otherwise reinsert) a subrange.
3589          *
3590          * - split destination inode's inline extents.  The inline extents can
3591          *   be either compressed or non-compressed.
3592          */
3593
3594         /* the destination must be opened for writing */
3595         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3596                 return -EINVAL;
3597
3598         if (btrfs_root_readonly(root))
3599                 return -EROFS;
3600
3601         ret = mnt_want_write_file(file);
3602         if (ret)
3603                 return ret;
3604
3605         src_file = fdget(srcfd);
3606         if (!src_file.file) {
3607                 ret = -EBADF;
3608                 goto out_drop_write;
3609         }
3610
3611         ret = -EXDEV;
3612         if (src_file.file->f_path.mnt != file->f_path.mnt)
3613                 goto out_fput;
3614
3615         src = file_inode(src_file.file);
3616
3617         ret = -EINVAL;
3618         if (src == inode)
3619                 same_inode = 1;
3620
3621         /* the src must be open for reading */
3622         if (!(src_file.file->f_mode & FMODE_READ))
3623                 goto out_fput;
3624
3625         /* don't make the dst file partly checksummed */
3626         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3627             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3628                 goto out_fput;
3629
3630         ret = -EISDIR;
3631         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3632                 goto out_fput;
3633
3634         ret = -EXDEV;
3635         if (src->i_sb != inode->i_sb)
3636                 goto out_fput;
3637
3638         if (!same_inode) {
3639                 if (inode < src) {
3640                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3641                         mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3642                 } else {
3643                         mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3644                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3645                 }
3646         } else {
3647                 mutex_lock(&src->i_mutex);
3648         }
3649
3650         /* determine range to clone */
3651         ret = -EINVAL;
3652         if (off + len > src->i_size || off + len < off)
3653                 goto out_unlock;
3654         if (len == 0)
3655                 olen = len = src->i_size - off;
3656         /* if we extend to eof, continue to block boundary */
3657         if (off + len == src->i_size)
3658                 len = ALIGN(src->i_size, bs) - off;
3659
3660         if (len == 0) {
3661                 ret = 0;
3662                 goto out_unlock;
3663         }
3664
3665         /* verify the end result is block aligned */
3666         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3667             !IS_ALIGNED(destoff, bs))
3668                 goto out_unlock;
3669
3670         /* verify if ranges are overlapped within the same file */
3671         if (same_inode) {
3672                 if (destoff + len > off && destoff < off + len)
3673                         goto out_unlock;
3674         }
3675
3676         if (destoff > inode->i_size) {
3677                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3678                 if (ret)
3679                         goto out_unlock;
3680         }
3681
3682         /*
3683          * Lock the target range too. Right after we replace the file extent
3684          * items in the fs tree (which now point to the cloned data), we might
3685          * have a worker replace them with extent items relative to a write
3686          * operation that was issued before this clone operation (i.e. confront
3687          * with inode.c:btrfs_finish_ordered_io).
3688          */
3689         if (same_inode) {
3690                 u64 lock_start = min_t(u64, off, destoff);
3691                 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3692
3693                 lock_extent_range(src, lock_start, lock_len);
3694         } else {
3695                 lock_extent_range(src, off, len);
3696                 lock_extent_range(inode, destoff, len);
3697         }
3698
3699         ret = btrfs_clone(src, inode, off, olen, len, destoff);
3700
3701         if (same_inode) {
3702                 u64 lock_start = min_t(u64, off, destoff);
3703                 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3704
3705                 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3706         } else {
3707                 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3708                 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3709                               destoff + len - 1);
3710         }
3711         /*
3712          * Truncate page cache pages so that future reads will see the cloned
3713          * data immediately and not the previous data.
3714          */
3715         truncate_inode_pages_range(&inode->i_data, destoff,
3716                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
3717 out_unlock:
3718         if (!same_inode) {
3719                 if (inode < src) {
3720                         mutex_unlock(&src->i_mutex);
3721                         mutex_unlock(&inode->i_mutex);
3722                 } else {
3723                         mutex_unlock(&inode->i_mutex);
3724                         mutex_unlock(&src->i_mutex);
3725                 }
3726         } else {
3727                 mutex_unlock(&src->i_mutex);
3728         }
3729 out_fput:
3730         fdput(src_file);
3731 out_drop_write:
3732         mnt_drop_write_file(file);
3733         return ret;
3734 }
3735
3736 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3737 {
3738         struct btrfs_ioctl_clone_range_args args;
3739
3740         if (copy_from_user(&args, argp, sizeof(args)))
3741                 return -EFAULT;
3742         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3743                                  args.src_length, args.dest_offset);
3744 }
3745
3746 /*
3747  * there are many ways the trans_start and trans_end ioctls can lead
3748  * to deadlocks.  They should only be used by applications that
3749  * basically own the machine, and have a very in depth understanding
3750  * of all the possible deadlocks and enospc problems.
3751  */
3752 static long btrfs_ioctl_trans_start(struct file *file)
3753 {
3754         struct inode *inode = file_inode(file);
3755         struct btrfs_root *root = BTRFS_I(inode)->root;
3756         struct btrfs_trans_handle *trans;
3757         int ret;
3758
3759         ret = -EPERM;
3760         if (!capable(CAP_SYS_ADMIN))
3761                 goto out;
3762
3763         ret = -EINPROGRESS;
3764         if (file->private_data)
3765                 goto out;
3766
3767         ret = -EROFS;
3768         if (btrfs_root_readonly(root))
3769                 goto out;
3770
3771         ret = mnt_want_write_file(file);
3772         if (ret)
3773                 goto out;
3774
3775         atomic_inc(&root->fs_info->open_ioctl_trans);
3776
3777         ret = -ENOMEM;
3778         trans = btrfs_start_ioctl_transaction(root);
3779         if (IS_ERR(trans))
3780                 goto out_drop;
3781
3782         file->private_data = trans;
3783         return 0;
3784
3785 out_drop:
3786         atomic_dec(&root->fs_info->open_ioctl_trans);
3787         mnt_drop_write_file(file);
3788 out:
3789         return ret;
3790 }
3791
3792 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3793 {
3794         struct inode *inode = file_inode(file);
3795         struct btrfs_root *root = BTRFS_I(inode)->root;
3796         struct btrfs_root *new_root;
3797         struct btrfs_dir_item *di;
3798         struct btrfs_trans_handle *trans;
3799         struct btrfs_path *path;
3800         struct btrfs_key location;
3801         struct btrfs_disk_key disk_key;
3802         u64 objectid = 0;
3803         u64 dir_id;
3804         int ret;
3805
3806         if (!capable(CAP_SYS_ADMIN))
3807                 return -EPERM;
3808
3809         ret = mnt_want_write_file(file);
3810         if (ret)
3811                 return ret;
3812
3813         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3814                 ret = -EFAULT;
3815                 goto out;
3816         }
3817
3818         if (!objectid)
3819                 objectid = BTRFS_FS_TREE_OBJECTID;
3820
3821         location.objectid = objectid;
3822         location.type = BTRFS_ROOT_ITEM_KEY;
3823         location.offset = (u64)-1;
3824
3825         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3826         if (IS_ERR(new_root)) {
3827                 ret = PTR_ERR(new_root);
3828                 goto out;
3829         }
3830
3831         path = btrfs_alloc_path();
3832         if (!path) {
3833                 ret = -ENOMEM;
3834                 goto out;
3835         }
3836         path->leave_spinning = 1;
3837
3838         trans = btrfs_start_transaction(root, 1);
3839         if (IS_ERR(trans)) {
3840                 btrfs_free_path(path);
3841                 ret = PTR_ERR(trans);
3842                 goto out;
3843         }
3844
3845         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3846         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3847                                    dir_id, "default", 7, 1);
3848         if (IS_ERR_OR_NULL(di)) {
3849                 btrfs_free_path(path);
3850                 btrfs_end_transaction(trans, root);
3851                 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3852                            "item, this isn't going to work");
3853                 ret = -ENOENT;
3854                 goto out;
3855         }
3856
3857         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3858         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3859         btrfs_mark_buffer_dirty(path->nodes[0]);
3860         btrfs_free_path(path);
3861
3862         btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3863         btrfs_end_transaction(trans, root);
3864 out:
3865         mnt_drop_write_file(file);
3866         return ret;
3867 }
3868
3869 void btrfs_get_block_group_info(struct list_head *groups_list,
3870                                 struct btrfs_ioctl_space_info *space)
3871 {
3872         struct btrfs_block_group_cache *block_group;
3873
3874         space->total_bytes = 0;
3875         space->used_bytes = 0;
3876         space->flags = 0;
3877         list_for_each_entry(block_group, groups_list, list) {
3878                 space->flags = block_group->flags;
3879                 space->total_bytes += block_group->key.offset;
3880                 space->used_bytes +=
3881                         btrfs_block_group_used(&block_group->item);
3882         }
3883 }
3884
3885 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3886 {
3887         struct btrfs_ioctl_space_args space_args;
3888         struct btrfs_ioctl_space_info space;
3889         struct btrfs_ioctl_space_info *dest;
3890         struct btrfs_ioctl_space_info *dest_orig;
3891         struct btrfs_ioctl_space_info __user *user_dest;
3892         struct btrfs_space_info *info;
3893         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3894                        BTRFS_BLOCK_GROUP_SYSTEM,
3895                        BTRFS_BLOCK_GROUP_METADATA,
3896                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3897         int num_types = 4;
3898         int alloc_size;
3899         int ret = 0;
3900         u64 slot_count = 0;
3901         int i, c;
3902
3903         if (copy_from_user(&space_args,
3904                            (struct btrfs_ioctl_space_args __user *)arg,
3905                            sizeof(space_args)))
3906                 return -EFAULT;
3907
3908         for (i = 0; i < num_types; i++) {
3909                 struct btrfs_space_info *tmp;
3910
3911                 info = NULL;
3912                 rcu_read_lock();
3913                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3914                                         list) {
3915                         if (tmp->flags == types[i]) {
3916                                 info = tmp;
3917                                 break;
3918                         }
3919                 }
3920                 rcu_read_unlock();
3921
3922                 if (!info)
3923                         continue;
3924
3925                 down_read(&info->groups_sem);
3926                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3927                         if (!list_empty(&info->block_groups[c]))
3928                                 slot_count++;
3929                 }
3930                 up_read(&info->groups_sem);
3931         }
3932
3933         /*
3934          * Global block reserve, exported as a space_info
3935          */
3936         slot_count++;
3937
3938         /* space_slots == 0 means they are asking for a count */
3939         if (space_args.space_slots == 0) {
3940                 space_args.total_spaces = slot_count;
3941                 goto out;
3942         }
3943
3944         slot_count = min_t(u64, space_args.space_slots, slot_count);
3945
3946         alloc_size = sizeof(*dest) * slot_count;
3947
3948         /* we generally have at most 6 or so space infos, one for each raid
3949          * level.  So, a whole page should be more than enough for everyone
3950          */
3951         if (alloc_size > PAGE_CACHE_SIZE)
3952                 return -ENOMEM;
3953
3954         space_args.total_spaces = 0;
3955         dest = kmalloc(alloc_size, GFP_NOFS);
3956         if (!dest)
3957                 return -ENOMEM;
3958         dest_orig = dest;
3959
3960         /* now we have a buffer to copy into */
3961         for (i = 0; i < num_types; i++) {
3962                 struct btrfs_space_info *tmp;
3963
3964                 if (!slot_count)
3965                         break;
3966
3967                 info = NULL;
3968                 rcu_read_lock();
3969                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3970                                         list) {
3971                         if (tmp->flags == types[i]) {
3972                                 info = tmp;
3973                                 break;
3974                         }
3975                 }
3976                 rcu_read_unlock();
3977
3978                 if (!info)
3979                         continue;
3980                 down_read(&info->groups_sem);
3981                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3982                         if (!list_empty(&info->block_groups[c])) {
3983                                 btrfs_get_block_group_info(
3984                                         &info->block_groups[c], &space);
3985                                 memcpy(dest, &space, sizeof(space));
3986                                 dest++;
3987                                 space_args.total_spaces++;
3988                                 slot_count--;
3989                         }
3990                         if (!slot_count)
3991                                 break;
3992                 }
3993                 up_read(&info->groups_sem);
3994         }
3995
3996         /*
3997          * Add global block reserve
3998          */
3999         if (slot_count) {
4000                 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
4001
4002                 spin_lock(&block_rsv->lock);
4003                 space.total_bytes = block_rsv->size;
4004                 space.used_bytes = block_rsv->size - block_rsv->reserved;
4005                 spin_unlock(&block_rsv->lock);
4006                 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4007                 memcpy(dest, &space, sizeof(space));
4008                 space_args.total_spaces++;
4009         }
4010
4011         user_dest = (struct btrfs_ioctl_space_info __user *)
4012                 (arg + sizeof(struct btrfs_ioctl_space_args));
4013
4014         if (copy_to_user(user_dest, dest_orig, alloc_size))
4015                 ret = -EFAULT;
4016
4017         kfree(dest_orig);
4018 out:
4019         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4020                 ret = -EFAULT;
4021
4022         return ret;
4023 }
4024
4025 /*
4026  * there are many ways the trans_start and trans_end ioctls can lead
4027  * to deadlocks.  They should only be used by applications that
4028  * basically own the machine, and have a very in depth understanding
4029  * of all the possible deadlocks and enospc problems.
4030  */
4031 long btrfs_ioctl_trans_end(struct file *file)
4032 {
4033         struct inode *inode = file_inode(file);
4034         struct btrfs_root *root = BTRFS_I(inode)->root;
4035         struct btrfs_trans_handle *trans;
4036
4037         trans = file->private_data;
4038         if (!trans)
4039                 return -EINVAL;
4040         file->private_data = NULL;
4041
4042         btrfs_end_transaction(trans, root);
4043
4044         atomic_dec(&root->fs_info->open_ioctl_trans);
4045
4046         mnt_drop_write_file(file);
4047         return 0;
4048 }
4049
4050 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4051                                             void __user *argp)
4052 {
4053         struct btrfs_trans_handle *trans;
4054         u64 transid;
4055         int ret;
4056
4057         trans = btrfs_attach_transaction_barrier(root);
4058         if (IS_ERR(trans)) {
4059                 if (PTR_ERR(trans) != -ENOENT)
4060                         return PTR_ERR(trans);
4061
4062                 /* No running transaction, don't bother */
4063                 transid = root->fs_info->last_trans_committed;
4064                 goto out;
4065         }
4066         transid = trans->transid;
4067         ret = btrfs_commit_transaction_async(trans, root, 0);
4068         if (ret) {
4069                 btrfs_end_transaction(trans, root);
4070                 return ret;
4071         }
4072 out:
4073         if (argp)
4074                 if (copy_to_user(argp, &transid, sizeof(transid)))
4075                         return -EFAULT;
4076         return 0;
4077 }
4078
4079 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4080                                            void __user *argp)
4081 {
4082         u64 transid;
4083
4084         if (argp) {
4085                 if (copy_from_user(&transid, argp, sizeof(transid)))
4086                         return -EFAULT;
4087         } else {
4088                 transid = 0;  /* current trans */
4089         }
4090         return btrfs_wait_for_commit(root, transid);
4091 }
4092
4093 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4094 {
4095         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4096         struct btrfs_ioctl_scrub_args *sa;
4097         int ret;
4098
4099         if (!capable(CAP_SYS_ADMIN))
4100                 return -EPERM;
4101
4102         sa = memdup_user(arg, sizeof(*sa));
4103         if (IS_ERR(sa))
4104                 return PTR_ERR(sa);
4105
4106         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4107                 ret = mnt_want_write_file(file);
4108                 if (ret)
4109                         goto out;
4110         }
4111
4112         ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4113                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4114                               0);
4115
4116         if (copy_to_user(arg, sa, sizeof(*sa)))
4117                 ret = -EFAULT;
4118
4119         if (!(sa->flags & BTRFS_SCRUB_READONLY))
4120                 mnt_drop_write_file(file);
4121 out:
4122         kfree(sa);
4123         return ret;
4124 }
4125
4126 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4127 {
4128         if (!capable(CAP_SYS_ADMIN))
4129                 return -EPERM;
4130
4131         return btrfs_scrub_cancel(root->fs_info);
4132 }
4133
4134 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4135                                        void __user *arg)
4136 {
4137         struct btrfs_ioctl_scrub_args *sa;
4138         int ret;
4139
4140         if (!capable(CAP_SYS_ADMIN))
4141                 return -EPERM;
4142
4143         sa = memdup_user(arg, sizeof(*sa));
4144         if (IS_ERR(sa))
4145                 return PTR_ERR(sa);
4146
4147         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4148
4149         if (copy_to_user(arg, sa, sizeof(*sa)))
4150                 ret = -EFAULT;
4151
4152         kfree(sa);
4153         return ret;
4154 }
4155
4156 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4157                                       void __user *arg)
4158 {
4159         struct btrfs_ioctl_get_dev_stats *sa;
4160         int ret;
4161
4162         sa = memdup_user(arg, sizeof(*sa));
4163         if (IS_ERR(sa))
4164                 return PTR_ERR(sa);
4165
4166         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4167                 kfree(sa);
4168                 return -EPERM;
4169         }
4170
4171         ret = btrfs_get_dev_stats(root, sa);
4172
4173         if (copy_to_user(arg, sa, sizeof(*sa)))
4174                 ret = -EFAULT;
4175
4176         kfree(sa);
4177         return ret;
4178 }
4179
4180 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4181 {
4182         struct btrfs_ioctl_dev_replace_args *p;
4183         int ret;
4184
4185         if (!capable(CAP_SYS_ADMIN))
4186                 return -EPERM;
4187
4188         p = memdup_user(arg, sizeof(*p));
4189         if (IS_ERR(p))
4190                 return PTR_ERR(p);
4191
4192         switch (p->cmd) {
4193         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4194                 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4195                         ret = -EROFS;
4196                         goto out;
4197                 }
4198                 if (atomic_xchg(
4199                         &root->fs_info->mutually_exclusive_operation_running,
4200                         1)) {
4201                         ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4202                 } else {
4203                         ret = btrfs_dev_replace_start(root, p);
4204                         atomic_set(
4205                          &root->fs_info->mutually_exclusive_operation_running,
4206                          0);
4207                 }
4208                 break;
4209         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4210                 btrfs_dev_replace_status(root->fs_info, p);
4211                 ret = 0;
4212                 break;
4213         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4214                 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4215                 break;
4216         default:
4217                 ret = -EINVAL;
4218                 break;
4219         }
4220
4221         if (copy_to_user(arg, p, sizeof(*p)))
4222                 ret = -EFAULT;
4223 out:
4224         kfree(p);
4225         return ret;
4226 }
4227
4228 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4229 {
4230         int ret = 0;
4231         int i;
4232         u64 rel_ptr;
4233         int size;
4234         struct btrfs_ioctl_ino_path_args *ipa = NULL;
4235         struct inode_fs_paths *ipath = NULL;
4236         struct btrfs_path *path;
4237
4238         if (!capable(CAP_DAC_READ_SEARCH))
4239                 return -EPERM;
4240
4241         path = btrfs_alloc_path();
4242         if (!path) {
4243                 ret = -ENOMEM;
4244                 goto out;
4245         }
4246
4247         ipa = memdup_user(arg, sizeof(*ipa));
4248         if (IS_ERR(ipa)) {
4249                 ret = PTR_ERR(ipa);
4250                 ipa = NULL;
4251                 goto out;
4252         }
4253
4254         size = min_t(u32, ipa->size, 4096);
4255         ipath = init_ipath(size, root, path);
4256         if (IS_ERR(ipath)) {
4257                 ret = PTR_ERR(ipath);
4258                 ipath = NULL;
4259                 goto out;
4260         }
4261
4262         ret = paths_from_inode(ipa->inum, ipath);
4263         if (ret < 0)
4264                 goto out;
4265
4266         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4267                 rel_ptr = ipath->fspath->val[i] -
4268                           (u64)(unsigned long)ipath->fspath->val;
4269                 ipath->fspath->val[i] = rel_ptr;
4270         }
4271
4272         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4273                            (void *)(unsigned long)ipath->fspath, size);
4274         if (ret) {
4275                 ret = -EFAULT;
4276                 goto out;
4277         }
4278
4279 out:
4280         btrfs_free_path(path);
4281         free_ipath(ipath);
4282         kfree(ipa);
4283
4284         return ret;
4285 }
4286
4287 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4288 {
4289         struct btrfs_data_container *inodes = ctx;
4290         const size_t c = 3 * sizeof(u64);
4291
4292         if (inodes->bytes_left >= c) {
4293                 inodes->bytes_left -= c;
4294                 inodes->val[inodes->elem_cnt] = inum;
4295                 inodes->val[inodes->elem_cnt + 1] = offset;
4296                 inodes->val[inodes->elem_cnt + 2] = root;
4297                 inodes->elem_cnt += 3;
4298         } else {
4299                 inodes->bytes_missing += c - inodes->bytes_left;
4300                 inodes->bytes_left = 0;
4301                 inodes->elem_missed += 3;
4302         }
4303
4304         return 0;
4305 }
4306
4307 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4308                                         void __user *arg)
4309 {
4310         int ret = 0;
4311         int size;
4312         struct btrfs_ioctl_logical_ino_args *loi;
4313         struct btrfs_data_container *inodes = NULL;
4314         struct btrfs_path *path = NULL;
4315
4316         if (!capable(CAP_SYS_ADMIN))
4317                 return -EPERM;
4318
4319         loi = memdup_user(arg, sizeof(*loi));
4320         if (IS_ERR(loi)) {
4321                 ret = PTR_ERR(loi);
4322                 loi = NULL;
4323                 goto out;
4324         }
4325
4326         path = btrfs_alloc_path();
4327         if (!path) {
4328                 ret = -ENOMEM;
4329                 goto out;
4330         }
4331
4332         size = min_t(u32, loi->size, 64 * 1024);
4333         inodes = init_data_container(size);
4334         if (IS_ERR(inodes)) {
4335                 ret = PTR_ERR(inodes);
4336                 inodes = NULL;
4337                 goto out;
4338         }
4339
4340         ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4341                                           build_ino_list, inodes);
4342         if (ret == -EINVAL)
4343                 ret = -ENOENT;
4344         if (ret < 0)
4345                 goto out;
4346
4347         ret = copy_to_user((void *)(unsigned long)loi->inodes,
4348                            (void *)(unsigned long)inodes, size);
4349         if (ret)
4350                 ret = -EFAULT;
4351
4352 out:
4353         btrfs_free_path(path);
4354         vfree(inodes);
4355         kfree(loi);
4356
4357         return ret;
4358 }
4359
4360 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4361                                struct btrfs_ioctl_balance_args *bargs)
4362 {
4363         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4364
4365         bargs->flags = bctl->flags;
4366
4367         if (atomic_read(&fs_info->balance_running))
4368                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4369         if (atomic_read(&fs_info->balance_pause_req))
4370                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4371         if (atomic_read(&fs_info->balance_cancel_req))
4372                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4373
4374         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4375         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4376         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4377
4378         if (lock) {
4379                 spin_lock(&fs_info->balance_lock);
4380                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4381                 spin_unlock(&fs_info->balance_lock);
4382         } else {
4383                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4384         }
4385 }
4386
4387 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4388 {
4389         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4390         struct btrfs_fs_info *fs_info = root->fs_info;
4391         struct btrfs_ioctl_balance_args *bargs;
4392         struct btrfs_balance_control *bctl;
4393         bool need_unlock; /* for mut. excl. ops lock */
4394         int ret;
4395
4396         if (!capable(CAP_SYS_ADMIN))
4397                 return -EPERM;
4398
4399         ret = mnt_want_write_file(file);
4400         if (ret)
4401                 return ret;
4402
4403 again:
4404         if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4405                 mutex_lock(&fs_info->volume_mutex);
4406                 mutex_lock(&fs_info->balance_mutex);
4407                 need_unlock = true;
4408                 goto locked;
4409         }
4410
4411         /*
4412          * mut. excl. ops lock is locked.  Three possibilites:
4413          *   (1) some other op is running
4414          *   (2) balance is running
4415          *   (3) balance is paused -- special case (think resume)
4416          */
4417         mutex_lock(&fs_info->balance_mutex);
4418         if (fs_info->balance_ctl) {
4419                 /* this is either (2) or (3) */
4420                 if (!atomic_read(&fs_info->balance_running)) {
4421                         mutex_unlock(&fs_info->balance_mutex);
4422                         if (!mutex_trylock(&fs_info->volume_mutex))
4423                                 goto again;
4424                         mutex_lock(&fs_info->balance_mutex);
4425
4426                         if (fs_info->balance_ctl &&
4427                             !atomic_read(&fs_info->balance_running)) {
4428                                 /* this is (3) */
4429                                 need_unlock = false;
4430                                 goto locked;
4431                         }
4432
4433                         mutex_unlock(&fs_info->balance_mutex);
4434                         mutex_unlock(&fs_info->volume_mutex);
4435                         goto again;
4436                 } else {
4437                         /* this is (2) */
4438                         mutex_unlock(&fs_info->balance_mutex);
4439                         ret = -EINPROGRESS;
4440                         goto out;
4441                 }
4442         } else {
4443                 /* this is (1) */
4444                 mutex_unlock(&fs_info->balance_mutex);
4445                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4446                 goto out;
4447         }
4448
4449 locked:
4450         BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4451
4452         if (arg) {
4453                 bargs = memdup_user(arg, sizeof(*bargs));
4454                 if (IS_ERR(bargs)) {
4455                         ret = PTR_ERR(bargs);
4456                         goto out_unlock;
4457                 }
4458
4459                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4460                         if (!fs_info->balance_ctl) {
4461                                 ret = -ENOTCONN;
4462                                 goto out_bargs;
4463                         }
4464
4465                         bctl = fs_info->balance_ctl;
4466                         spin_lock(&fs_info->balance_lock);
4467                         bctl->flags |= BTRFS_BALANCE_RESUME;
4468                         spin_unlock(&fs_info->balance_lock);
4469
4470                         goto do_balance;
4471                 }
4472         } else {
4473                 bargs = NULL;
4474         }
4475
4476         if (fs_info->balance_ctl) {
4477                 ret = -EINPROGRESS;
4478                 goto out_bargs;
4479         }
4480
4481         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4482         if (!bctl) {
4483                 ret = -ENOMEM;
4484                 goto out_bargs;
4485         }
4486
4487         bctl->fs_info = fs_info;
4488         if (arg) {
4489                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4490                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4491                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4492
4493                 bctl->flags = bargs->flags;
4494         } else {
4495                 /* balance everything - no filters */
4496                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4497         }
4498
4499 do_balance:
4500         /*
4501          * Ownership of bctl and mutually_exclusive_operation_running
4502          * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
4503          * or, if restriper was paused all the way until unmount, in
4504          * free_fs_info.  mutually_exclusive_operation_running is
4505          * cleared in __cancel_balance.
4506          */
4507         need_unlock = false;
4508
4509         ret = btrfs_balance(bctl, bargs);
4510
4511         if (arg) {
4512                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4513                         ret = -EFAULT;
4514         }
4515
4516 out_bargs:
4517         kfree(bargs);
4518 out_unlock:
4519         mutex_unlock(&fs_info->balance_mutex);
4520         mutex_unlock(&fs_info->volume_mutex);
4521         if (need_unlock)
4522                 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4523 out:
4524         mnt_drop_write_file(file);
4525         return ret;
4526 }
4527
4528 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4529 {
4530         if (!capable(CAP_SYS_ADMIN))
4531                 return -EPERM;
4532
4533         switch (cmd) {
4534         case BTRFS_BALANCE_CTL_PAUSE:
4535                 return btrfs_pause_balance(root->fs_info);
4536         case BTRFS_BALANCE_CTL_CANCEL:
4537                 return btrfs_cancel_balance(root->fs_info);
4538         }
4539
4540         return -EINVAL;
4541 }
4542
4543 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4544                                          void __user *arg)
4545 {
4546         struct btrfs_fs_info *fs_info = root->fs_info;
4547         struct btrfs_ioctl_balance_args *bargs;
4548         int ret = 0;
4549
4550         if (!capable(CAP_SYS_ADMIN))
4551                 return -EPERM;
4552
4553         mutex_lock(&fs_info->balance_mutex);
4554         if (!fs_info->balance_ctl) {
4555                 ret = -ENOTCONN;
4556                 goto out;
4557         }
4558
4559         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4560         if (!bargs) {
4561                 ret = -ENOMEM;
4562                 goto out;
4563         }
4564
4565         update_ioctl_balance_args(fs_info, 1, bargs);
4566
4567         if (copy_to_user(arg, bargs, sizeof(*bargs)))
4568                 ret = -EFAULT;
4569
4570         kfree(bargs);
4571 out:
4572         mutex_unlock(&fs_info->balance_mutex);
4573         return ret;
4574 }
4575
4576 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4577 {
4578         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4579         struct btrfs_ioctl_quota_ctl_args *sa;
4580         struct btrfs_trans_handle *trans = NULL;
4581         int ret;
4582         int err;
4583
4584         if (!capable(CAP_SYS_ADMIN))
4585                 return -EPERM;
4586
4587         ret = mnt_want_write_file(file);
4588         if (ret)
4589                 return ret;
4590
4591         sa = memdup_user(arg, sizeof(*sa));
4592         if (IS_ERR(sa)) {
4593                 ret = PTR_ERR(sa);
4594                 goto drop_write;
4595         }
4596
4597         down_write(&root->fs_info->subvol_sem);
4598         trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4599         if (IS_ERR(trans)) {
4600                 ret = PTR_ERR(trans);
4601                 goto out;
4602         }
4603
4604         switch (sa->cmd) {
4605         case BTRFS_QUOTA_CTL_ENABLE:
4606                 ret = btrfs_quota_enable(trans, root->fs_info);
4607                 break;
4608         case BTRFS_QUOTA_CTL_DISABLE:
4609                 ret = btrfs_quota_disable(trans, root->fs_info);
4610                 break;
4611         default:
4612                 ret = -EINVAL;
4613                 break;
4614         }
4615
4616         err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4617         if (err && !ret)
4618                 ret = err;
4619 out:
4620         kfree(sa);
4621         up_write(&root->fs_info->subvol_sem);
4622 drop_write:
4623         mnt_drop_write_file(file);
4624         return ret;
4625 }
4626
4627 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4628 {
4629         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4630         struct btrfs_ioctl_qgroup_assign_args *sa;
4631         struct btrfs_trans_handle *trans;
4632         int ret;
4633         int err;
4634
4635         if (!capable(CAP_SYS_ADMIN))
4636                 return -EPERM;
4637
4638         ret = mnt_want_write_file(file);
4639         if (ret)
4640                 return ret;
4641
4642         sa = memdup_user(arg, sizeof(*sa));
4643         if (IS_ERR(sa)) {
4644                 ret = PTR_ERR(sa);
4645                 goto drop_write;
4646         }
4647
4648         trans = btrfs_join_transaction(root);
4649         if (IS_ERR(trans)) {
4650                 ret = PTR_ERR(trans);
4651                 goto out;
4652         }
4653
4654         /* FIXME: check if the IDs really exist */
4655         if (sa->assign) {
4656                 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4657                                                 sa->src, sa->dst);
4658         } else {
4659                 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4660                                                 sa->src, sa->dst);
4661         }
4662
4663         /* update qgroup status and info */
4664         err = btrfs_run_qgroups(trans, root->fs_info);
4665         if (err < 0)
4666                 btrfs_error(root->fs_info, ret,
4667                             "failed to update qgroup status and info\n");
4668         err = btrfs_end_transaction(trans, root);
4669         if (err && !ret)
4670                 ret = err;
4671
4672 out:
4673         kfree(sa);
4674 drop_write:
4675         mnt_drop_write_file(file);
4676         return ret;
4677 }
4678
4679 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4680 {
4681         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4682         struct btrfs_ioctl_qgroup_create_args *sa;
4683         struct btrfs_trans_handle *trans;
4684         int ret;
4685         int err;
4686
4687         if (!capable(CAP_SYS_ADMIN))
4688                 return -EPERM;
4689
4690         ret = mnt_want_write_file(file);
4691         if (ret)
4692                 return ret;
4693
4694         sa = memdup_user(arg, sizeof(*sa));
4695         if (IS_ERR(sa)) {
4696                 ret = PTR_ERR(sa);
4697                 goto drop_write;
4698         }
4699
4700         if (!sa->qgroupid) {
4701                 ret = -EINVAL;
4702                 goto out;
4703         }
4704
4705         trans = btrfs_join_transaction(root);
4706         if (IS_ERR(trans)) {
4707                 ret = PTR_ERR(trans);
4708                 goto out;
4709         }
4710
4711         /* FIXME: check if the IDs really exist */
4712         if (sa->create) {
4713                 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid);
4714         } else {
4715                 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4716         }
4717
4718         err = btrfs_end_transaction(trans, root);
4719         if (err && !ret)
4720                 ret = err;
4721
4722 out:
4723         kfree(sa);
4724 drop_write:
4725         mnt_drop_write_file(file);
4726         return ret;
4727 }
4728
4729 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4730 {
4731         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4732         struct btrfs_ioctl_qgroup_limit_args *sa;
4733         struct btrfs_trans_handle *trans;
4734         int ret;
4735         int err;
4736         u64 qgroupid;
4737
4738         if (!capable(CAP_SYS_ADMIN))
4739                 return -EPERM;
4740
4741         ret = mnt_want_write_file(file);
4742         if (ret)
4743                 return ret;
4744
4745         sa = memdup_user(arg, sizeof(*sa));
4746         if (IS_ERR(sa)) {
4747                 ret = PTR_ERR(sa);
4748                 goto drop_write;
4749         }
4750
4751         trans = btrfs_join_transaction(root);
4752         if (IS_ERR(trans)) {
4753                 ret = PTR_ERR(trans);
4754                 goto out;
4755         }
4756
4757         qgroupid = sa->qgroupid;
4758         if (!qgroupid) {
4759                 /* take the current subvol as qgroup */
4760                 qgroupid = root->root_key.objectid;
4761         }
4762
4763         /* FIXME: check if the IDs really exist */
4764         ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4765
4766         err = btrfs_end_transaction(trans, root);
4767         if (err && !ret)
4768                 ret = err;
4769
4770 out:
4771         kfree(sa);
4772 drop_write:
4773         mnt_drop_write_file(file);
4774         return ret;
4775 }
4776
4777 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4778 {
4779         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4780         struct btrfs_ioctl_quota_rescan_args *qsa;
4781         int ret;
4782
4783         if (!capable(CAP_SYS_ADMIN))
4784                 return -EPERM;
4785
4786         ret = mnt_want_write_file(file);
4787         if (ret)
4788                 return ret;
4789
4790         qsa = memdup_user(arg, sizeof(*qsa));
4791         if (IS_ERR(qsa)) {
4792                 ret = PTR_ERR(qsa);
4793                 goto drop_write;
4794         }
4795
4796         if (qsa->flags) {
4797                 ret = -EINVAL;
4798                 goto out;
4799         }
4800
4801         ret = btrfs_qgroup_rescan(root->fs_info);
4802
4803 out:
4804         kfree(qsa);
4805 drop_write:
4806         mnt_drop_write_file(file);
4807         return ret;
4808 }
4809
4810 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4811 {
4812         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4813         struct btrfs_ioctl_quota_rescan_args *qsa;
4814         int ret = 0;
4815
4816         if (!capable(CAP_SYS_ADMIN))
4817                 return -EPERM;
4818
4819         qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4820         if (!qsa)
4821                 return -ENOMEM;
4822
4823         if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4824                 qsa->flags = 1;
4825                 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4826         }
4827
4828         if (copy_to_user(arg, qsa, sizeof(*qsa)))
4829                 ret = -EFAULT;
4830
4831         kfree(qsa);
4832         return ret;
4833 }
4834
4835 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4836 {
4837         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4838
4839         if (!capable(CAP_SYS_ADMIN))
4840                 return -EPERM;
4841
4842         return btrfs_qgroup_wait_for_completion(root->fs_info);
4843 }
4844
4845 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4846                                             struct btrfs_ioctl_received_subvol_args *sa)
4847 {
4848         struct inode *inode = file_inode(file);
4849         struct btrfs_root *root = BTRFS_I(inode)->root;
4850         struct btrfs_root_item *root_item = &root->root_item;
4851         struct btrfs_trans_handle *trans;
4852         struct timespec ct = CURRENT_TIME;
4853         int ret = 0;
4854         int received_uuid_changed;
4855
4856         if (!inode_owner_or_capable(inode))
4857                 return -EPERM;
4858
4859         ret = mnt_want_write_file(file);
4860         if (ret < 0)
4861                 return ret;
4862
4863         down_write(&root->fs_info->subvol_sem);
4864
4865         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4866                 ret = -EINVAL;
4867                 goto out;
4868         }
4869
4870         if (btrfs_root_readonly(root)) {
4871                 ret = -EROFS;
4872                 goto out;
4873         }
4874
4875         /*
4876          * 1 - root item
4877          * 2 - uuid items (received uuid + subvol uuid)
4878          */
4879         trans = btrfs_start_transaction(root, 3);
4880         if (IS_ERR(trans)) {
4881                 ret = PTR_ERR(trans);
4882                 trans = NULL;
4883                 goto out;
4884         }
4885
4886         sa->rtransid = trans->transid;
4887         sa->rtime.sec = ct.tv_sec;
4888         sa->rtime.nsec = ct.tv_nsec;
4889
4890         received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4891                                        BTRFS_UUID_SIZE);
4892         if (received_uuid_changed &&
4893             !btrfs_is_empty_uuid(root_item->received_uuid))
4894                 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4895                                     root_item->received_uuid,
4896                                     BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4897                                     root->root_key.objectid);
4898         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4899         btrfs_set_root_stransid(root_item, sa->stransid);
4900         btrfs_set_root_rtransid(root_item, sa->rtransid);
4901         btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4902         btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4903         btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4904         btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4905
4906         ret = btrfs_update_root(trans, root->fs_info->tree_root,
4907                                 &root->root_key, &root->root_item);
4908         if (ret < 0) {
4909                 btrfs_end_transaction(trans, root);
4910                 goto out;
4911         }
4912         if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4913                 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4914                                           sa->uuid,
4915                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4916                                           root->root_key.objectid);
4917                 if (ret < 0 && ret != -EEXIST) {
4918                         btrfs_abort_transaction(trans, root, ret);
4919                         goto out;
4920                 }
4921         }
4922         ret = btrfs_commit_transaction(trans, root);
4923         if (ret < 0) {
4924                 btrfs_abort_transaction(trans, root, ret);
4925                 goto out;
4926         }
4927
4928 out:
4929         up_write(&root->fs_info->subvol_sem);
4930         mnt_drop_write_file(file);
4931         return ret;
4932 }
4933
4934 #ifdef CONFIG_64BIT
4935 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4936                                                 void __user *arg)
4937 {
4938         struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4939         struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4940         int ret = 0;
4941
4942         args32 = memdup_user(arg, sizeof(*args32));
4943         if (IS_ERR(args32)) {
4944                 ret = PTR_ERR(args32);
4945                 args32 = NULL;
4946                 goto out;
4947         }
4948
4949         args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4950         if (!args64) {
4951                 ret = -ENOMEM;
4952                 goto out;
4953         }
4954
4955         memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4956         args64->stransid = args32->stransid;
4957         args64->rtransid = args32->rtransid;
4958         args64->stime.sec = args32->stime.sec;
4959         args64->stime.nsec = args32->stime.nsec;
4960         args64->rtime.sec = args32->rtime.sec;
4961         args64->rtime.nsec = args32->rtime.nsec;
4962         args64->flags = args32->flags;
4963
4964         ret = _btrfs_ioctl_set_received_subvol(file, args64);
4965         if (ret)
4966                 goto out;
4967
4968         memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4969         args32->stransid = args64->stransid;
4970         args32->rtransid = args64->rtransid;
4971         args32->stime.sec = args64->stime.sec;
4972         args32->stime.nsec = args64->stime.nsec;
4973         args32->rtime.sec = args64->rtime.sec;
4974         args32->rtime.nsec = args64->rtime.nsec;
4975         args32->flags = args64->flags;
4976
4977         ret = copy_to_user(arg, args32, sizeof(*args32));
4978         if (ret)
4979                 ret = -EFAULT;
4980
4981 out:
4982         kfree(args32);
4983         kfree(args64);
4984         return ret;
4985 }
4986 #endif
4987
4988 static long btrfs_ioctl_set_received_subvol(struct file *file,
4989                                             void __user *arg)
4990 {
4991         struct btrfs_ioctl_received_subvol_args *sa = NULL;
4992         int ret = 0;
4993
4994         sa = memdup_user(arg, sizeof(*sa));
4995         if (IS_ERR(sa)) {
4996                 ret = PTR_ERR(sa);
4997                 sa = NULL;
4998                 goto out;
4999         }
5000
5001         ret = _btrfs_ioctl_set_received_subvol(file, sa);
5002
5003         if (ret)
5004                 goto out;
5005
5006         ret = copy_to_user(arg, sa, sizeof(*sa));
5007         if (ret)
5008                 ret = -EFAULT;
5009
5010 out:
5011         kfree(sa);
5012         return ret;
5013 }
5014
5015 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5016 {
5017         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5018         size_t len;
5019         int ret;
5020         char label[BTRFS_LABEL_SIZE];
5021
5022         spin_lock(&root->fs_info->super_lock);
5023         memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5024         spin_unlock(&root->fs_info->super_lock);
5025
5026         len = strnlen(label, BTRFS_LABEL_SIZE);
5027
5028         if (len == BTRFS_LABEL_SIZE) {
5029                 btrfs_warn(root->fs_info,
5030                         "label is too long, return the first %zu bytes", --len);
5031         }
5032
5033         ret = copy_to_user(arg, label, len);
5034
5035         return ret ? -EFAULT : 0;
5036 }
5037
5038 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5039 {
5040         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5041         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5042         struct btrfs_trans_handle *trans;
5043         char label[BTRFS_LABEL_SIZE];
5044         int ret;
5045
5046         if (!capable(CAP_SYS_ADMIN))
5047                 return -EPERM;
5048
5049         if (copy_from_user(label, arg, sizeof(label)))
5050                 return -EFAULT;
5051
5052         if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5053                 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5054                        BTRFS_LABEL_SIZE - 1);
5055                 return -EINVAL;
5056         }
5057
5058         ret = mnt_want_write_file(file);
5059         if (ret)
5060                 return ret;
5061
5062         trans = btrfs_start_transaction(root, 0);
5063         if (IS_ERR(trans)) {
5064                 ret = PTR_ERR(trans);
5065                 goto out_unlock;
5066         }
5067
5068         spin_lock(&root->fs_info->super_lock);
5069         strcpy(super_block->label, label);
5070         spin_unlock(&root->fs_info->super_lock);
5071         ret = btrfs_commit_transaction(trans, root);
5072
5073 out_unlock:
5074         mnt_drop_write_file(file);
5075         return ret;
5076 }
5077
5078 #define INIT_FEATURE_FLAGS(suffix) \
5079         { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5080           .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5081           .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5082
5083 static int btrfs_ioctl_get_supported_features(struct file *file,
5084                                               void __user *arg)
5085 {
5086         static struct btrfs_ioctl_feature_flags features[3] = {
5087                 INIT_FEATURE_FLAGS(SUPP),
5088                 INIT_FEATURE_FLAGS(SAFE_SET),
5089                 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5090         };
5091
5092         if (copy_to_user(arg, &features, sizeof(features)))
5093                 return -EFAULT;
5094
5095         return 0;
5096 }
5097
5098 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5099 {
5100         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5101         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5102         struct btrfs_ioctl_feature_flags features;
5103
5104         features.compat_flags = btrfs_super_compat_flags(super_block);
5105         features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5106         features.incompat_flags = btrfs_super_incompat_flags(super_block);
5107
5108         if (copy_to_user(arg, &features, sizeof(features)))
5109                 return -EFAULT;
5110
5111         return 0;
5112 }
5113
5114 static int check_feature_bits(struct btrfs_root *root,
5115                               enum btrfs_feature_set set,
5116                               u64 change_mask, u64 flags, u64 supported_flags,
5117                               u64 safe_set, u64 safe_clear)
5118 {
5119         const char *type = btrfs_feature_set_names[set];
5120         char *names;
5121         u64 disallowed, unsupported;
5122         u64 set_mask = flags & change_mask;
5123         u64 clear_mask = ~flags & change_mask;
5124
5125         unsupported = set_mask & ~supported_flags;
5126         if (unsupported) {
5127                 names = btrfs_printable_features(set, unsupported);
5128                 if (names) {
5129                         btrfs_warn(root->fs_info,
5130                            "this kernel does not support the %s feature bit%s",
5131                            names, strchr(names, ',') ? "s" : "");
5132                         kfree(names);
5133                 } else
5134                         btrfs_warn(root->fs_info,
5135                            "this kernel does not support %s bits 0x%llx",
5136                            type, unsupported);
5137                 return -EOPNOTSUPP;
5138         }
5139
5140         disallowed = set_mask & ~safe_set;
5141         if (disallowed) {
5142                 names = btrfs_printable_features(set, disallowed);
5143                 if (names) {
5144                         btrfs_warn(root->fs_info,
5145                            "can't set the %s feature bit%s while mounted",
5146                            names, strchr(names, ',') ? "s" : "");
5147                         kfree(names);
5148                 } else
5149                         btrfs_warn(root->fs_info,
5150                            "can't set %s bits 0x%llx while mounted",
5151                            type, disallowed);
5152                 return -EPERM;
5153         }
5154
5155         disallowed = clear_mask & ~safe_clear;
5156         if (disallowed) {
5157                 names = btrfs_printable_features(set, disallowed);
5158                 if (names) {
5159                         btrfs_warn(root->fs_info,
5160                            "can't clear the %s feature bit%s while mounted",
5161                            names, strchr(names, ',') ? "s" : "");
5162                         kfree(names);
5163                 } else
5164                         btrfs_warn(root->fs_info,
5165                            "can't clear %s bits 0x%llx while mounted",
5166                            type, disallowed);
5167                 return -EPERM;
5168         }
5169
5170         return 0;
5171 }
5172
5173 #define check_feature(root, change_mask, flags, mask_base)      \
5174 check_feature_bits(root, FEAT_##mask_base, change_mask, flags,  \
5175                    BTRFS_FEATURE_ ## mask_base ## _SUPP,        \
5176                    BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,    \
5177                    BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5178
5179 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5180 {
5181         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5182         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5183         struct btrfs_ioctl_feature_flags flags[2];
5184         struct btrfs_trans_handle *trans;
5185         u64 newflags;
5186         int ret;
5187
5188         if (!capable(CAP_SYS_ADMIN))
5189                 return -EPERM;
5190
5191         if (copy_from_user(flags, arg, sizeof(flags)))
5192                 return -EFAULT;
5193
5194         /* Nothing to do */
5195         if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5196             !flags[0].incompat_flags)
5197                 return 0;
5198
5199         ret = check_feature(root, flags[0].compat_flags,
5200                             flags[1].compat_flags, COMPAT);
5201         if (ret)
5202                 return ret;
5203
5204         ret = check_feature(root, flags[0].compat_ro_flags,
5205                             flags[1].compat_ro_flags, COMPAT_RO);
5206         if (ret)
5207                 return ret;
5208
5209         ret = check_feature(root, flags[0].incompat_flags,
5210                             flags[1].incompat_flags, INCOMPAT);
5211         if (ret)
5212                 return ret;
5213
5214         trans = btrfs_start_transaction(root, 0);
5215         if (IS_ERR(trans))
5216                 return PTR_ERR(trans);
5217
5218         spin_lock(&root->fs_info->super_lock);
5219         newflags = btrfs_super_compat_flags(super_block);
5220         newflags |= flags[0].compat_flags & flags[1].compat_flags;
5221         newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5222         btrfs_set_super_compat_flags(super_block, newflags);
5223
5224         newflags = btrfs_super_compat_ro_flags(super_block);
5225         newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5226         newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5227         btrfs_set_super_compat_ro_flags(super_block, newflags);
5228
5229         newflags = btrfs_super_incompat_flags(super_block);
5230         newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5231         newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5232         btrfs_set_super_incompat_flags(super_block, newflags);
5233         spin_unlock(&root->fs_info->super_lock);
5234
5235         return btrfs_commit_transaction(trans, root);
5236 }
5237
5238 long btrfs_ioctl(struct file *file, unsigned int
5239                 cmd, unsigned long arg)
5240 {
5241         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5242         void __user *argp = (void __user *)arg;
5243
5244         switch (cmd) {
5245         case FS_IOC_GETFLAGS:
5246                 return btrfs_ioctl_getflags(file, argp);
5247         case FS_IOC_SETFLAGS:
5248                 return btrfs_ioctl_setflags(file, argp);
5249         case FS_IOC_GETVERSION:
5250                 return btrfs_ioctl_getversion(file, argp);
5251         case FITRIM:
5252                 return btrfs_ioctl_fitrim(file, argp);
5253         case BTRFS_IOC_SNAP_CREATE:
5254                 return btrfs_ioctl_snap_create(file, argp, 0);
5255         case BTRFS_IOC_SNAP_CREATE_V2:
5256                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5257         case BTRFS_IOC_SUBVOL_CREATE:
5258                 return btrfs_ioctl_snap_create(file, argp, 1);
5259         case BTRFS_IOC_SUBVOL_CREATE_V2:
5260                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5261         case BTRFS_IOC_SNAP_DESTROY:
5262                 return btrfs_ioctl_snap_destroy(file, argp);
5263         case BTRFS_IOC_SUBVOL_GETFLAGS:
5264                 return btrfs_ioctl_subvol_getflags(file, argp);
5265         case BTRFS_IOC_SUBVOL_SETFLAGS:
5266                 return btrfs_ioctl_subvol_setflags(file, argp);
5267         case BTRFS_IOC_DEFAULT_SUBVOL:
5268                 return btrfs_ioctl_default_subvol(file, argp);
5269         case BTRFS_IOC_DEFRAG:
5270                 return btrfs_ioctl_defrag(file, NULL);
5271         case BTRFS_IOC_DEFRAG_RANGE:
5272                 return btrfs_ioctl_defrag(file, argp);
5273         case BTRFS_IOC_RESIZE:
5274                 return btrfs_ioctl_resize(file, argp);
5275         case BTRFS_IOC_ADD_DEV:
5276                 return btrfs_ioctl_add_dev(root, argp);
5277         case BTRFS_IOC_RM_DEV:
5278                 return btrfs_ioctl_rm_dev(file, argp);
5279         case BTRFS_IOC_FS_INFO:
5280                 return btrfs_ioctl_fs_info(root, argp);
5281         case BTRFS_IOC_DEV_INFO:
5282                 return btrfs_ioctl_dev_info(root, argp);
5283         case BTRFS_IOC_BALANCE:
5284                 return btrfs_ioctl_balance(file, NULL);
5285         case BTRFS_IOC_CLONE:
5286                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5287         case BTRFS_IOC_CLONE_RANGE:
5288                 return btrfs_ioctl_clone_range(file, argp);
5289         case BTRFS_IOC_TRANS_START:
5290                 return btrfs_ioctl_trans_start(file);
5291         case BTRFS_IOC_TRANS_END:
5292                 return btrfs_ioctl_trans_end(file);
5293         case BTRFS_IOC_TREE_SEARCH:
5294                 return btrfs_ioctl_tree_search(file, argp);
5295         case BTRFS_IOC_TREE_SEARCH_V2:
5296                 return btrfs_ioctl_tree_search_v2(file, argp);
5297         case BTRFS_IOC_INO_LOOKUP:
5298                 return btrfs_ioctl_ino_lookup(file, argp);
5299         case BTRFS_IOC_INO_PATHS:
5300                 return btrfs_ioctl_ino_to_path(root, argp);
5301         case BTRFS_IOC_LOGICAL_INO:
5302                 return btrfs_ioctl_logical_to_ino(root, argp);
5303         case BTRFS_IOC_SPACE_INFO:
5304                 return btrfs_ioctl_space_info(root, argp);
5305         case BTRFS_IOC_SYNC: {
5306                 int ret;
5307
5308                 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5309                 if (ret)
5310                         return ret;
5311                 ret = btrfs_sync_fs(file_inode(file)->i_sb, 1);
5312                 /*
5313                  * The transaction thread may want to do more work,
5314                  * namely it pokes the cleaner ktread that will start
5315                  * processing uncleaned subvols.
5316                  */
5317                 wake_up_process(root->fs_info->transaction_kthread);
5318                 return ret;
5319         }
5320         case BTRFS_IOC_START_SYNC:
5321                 return btrfs_ioctl_start_sync(root, argp);
5322         case BTRFS_IOC_WAIT_SYNC:
5323                 return btrfs_ioctl_wait_sync(root, argp);
5324         case BTRFS_IOC_SCRUB:
5325                 return btrfs_ioctl_scrub(file, argp);
5326         case BTRFS_IOC_SCRUB_CANCEL:
5327                 return btrfs_ioctl_scrub_cancel(root, argp);
5328         case BTRFS_IOC_SCRUB_PROGRESS:
5329                 return btrfs_ioctl_scrub_progress(root, argp);
5330         case BTRFS_IOC_BALANCE_V2:
5331                 return btrfs_ioctl_balance(file, argp);
5332         case BTRFS_IOC_BALANCE_CTL:
5333                 return btrfs_ioctl_balance_ctl(root, arg);
5334         case BTRFS_IOC_BALANCE_PROGRESS:
5335                 return btrfs_ioctl_balance_progress(root, argp);
5336         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5337                 return btrfs_ioctl_set_received_subvol(file, argp);
5338 #ifdef CONFIG_64BIT
5339         case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5340                 return btrfs_ioctl_set_received_subvol_32(file, argp);
5341 #endif
5342         case BTRFS_IOC_SEND:
5343                 return btrfs_ioctl_send(file, argp);
5344         case BTRFS_IOC_GET_DEV_STATS:
5345                 return btrfs_ioctl_get_dev_stats(root, argp);
5346         case BTRFS_IOC_QUOTA_CTL:
5347                 return btrfs_ioctl_quota_ctl(file, argp);
5348         case BTRFS_IOC_QGROUP_ASSIGN:
5349                 return btrfs_ioctl_qgroup_assign(file, argp);
5350         case BTRFS_IOC_QGROUP_CREATE:
5351                 return btrfs_ioctl_qgroup_create(file, argp);
5352         case BTRFS_IOC_QGROUP_LIMIT:
5353                 return btrfs_ioctl_qgroup_limit(file, argp);
5354         case BTRFS_IOC_QUOTA_RESCAN:
5355                 return btrfs_ioctl_quota_rescan(file, argp);
5356         case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5357                 return btrfs_ioctl_quota_rescan_status(file, argp);
5358         case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5359                 return btrfs_ioctl_quota_rescan_wait(file, argp);
5360         case BTRFS_IOC_DEV_REPLACE:
5361                 return btrfs_ioctl_dev_replace(root, argp);
5362         case BTRFS_IOC_GET_FSLABEL:
5363                 return btrfs_ioctl_get_fslabel(file, argp);
5364         case BTRFS_IOC_SET_FSLABEL:
5365                 return btrfs_ioctl_set_fslabel(file, argp);
5366         case BTRFS_IOC_FILE_EXTENT_SAME:
5367                 return btrfs_ioctl_file_extent_same(file, argp);
5368         case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5369                 return btrfs_ioctl_get_supported_features(file, argp);
5370         case BTRFS_IOC_GET_FEATURES:
5371                 return btrfs_ioctl_get_features(file, argp);
5372         case BTRFS_IOC_SET_FEATURES:
5373                 return btrfs_ioctl_set_features(file, argp);
5374         }
5375
5376         return -ENOTTY;
5377 }