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         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 460         /*
 461          * The same as the snapshot creation, please see the comment
 462          * of create_snapshot().
 463          */
 464         ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
 465                                                8, &qgroup_reserved, false);
 466         if (ret)
 467                 return ret;
 468
 469         trans = btrfs_start_transaction(root, 0);
 470         if (IS_ERR(trans)) {
 471                 ret = PTR_ERR(trans);
 472                 btrfs_subvolume_release_metadata(root, &block_rsv,
 473                                                  qgroup_reserved);
 474                 return ret;
 475         }
 476         trans->block_rsv = &block_rsv;
 477         trans->bytes_reserved = block_rsv.size;
 478
 479         ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
 480         if (ret)
 481                 goto fail;
 482
 483         leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
 484         if (IS_ERR(leaf)) {
 485                 ret = PTR_ERR(leaf);
 486                 goto fail;
 487         }
 488
 489         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 490         btrfs_set_header_bytenr(leaf, leaf->start);
 491         btrfs_set_header_generation(leaf, trans->transid);
 492         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 493         btrfs_set_header_owner(leaf, objectid);
 494
 495         write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
 496                             BTRFS_FSID_SIZE);
 497         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 498                             btrfs_header_chunk_tree_uuid(leaf),
 499                             BTRFS_UUID_SIZE);
 500         btrfs_mark_buffer_dirty(leaf);
 501
 502         memset(&root_item, 0, sizeof(root_item));
 503
 504         inode_item = &root_item.inode;
 505         btrfs_set_stack_inode_generation(inode_item, 1);
 506         btrfs_set_stack_inode_size(inode_item, 3);
 507         btrfs_set_stack_inode_nlink(inode_item, 1);
 508         btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
 509         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 510
 511         btrfs_set_root_flags(&root_item, 0);
 512         btrfs_set_root_limit(&root_item, 0);
 513         btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 514
 515         btrfs_set_root_bytenr(&root_item, leaf->start);
 516         btrfs_set_root_generation(&root_item, trans->transid);
 517         btrfs_set_root_level(&root_item, 0);
 518         btrfs_set_root_refs(&root_item, 1);
 519         btrfs_set_root_used(&root_item, leaf->len);
 520         btrfs_set_root_last_snapshot(&root_item, 0);
 521
 522         btrfs_set_root_generation_v2(&root_item,
 523                         btrfs_root_generation(&root_item));
 524         uuid_le_gen(&new_uuid);
 525         memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
 526         btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
 527         btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
 528         root_item.ctime = root_item.otime;
 529         btrfs_set_root_ctransid(&root_item, trans->transid);
 530         btrfs_set_root_otransid(&root_item, trans->transid);
 531
 532         btrfs_tree_unlock(leaf);
 533         free_extent_buffer(leaf);
 534         leaf = NULL;
 535
 536         btrfs_set_root_dirid(&root_item, new_dirid);
 537
 538         key.objectid = objectid;
 539         key.offset = 0;
 540         key.type = BTRFS_ROOT_ITEM_KEY;
 541         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 542                                 &root_item);
 543         if (ret)
 544                 goto fail;
 545
 546         key.offset = (u64)-1;
 547         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 548         if (IS_ERR(new_root)) {
 549                 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 550                 ret = PTR_ERR(new_root);
 551                 goto fail;
 552         }
 553
 554         btrfs_record_root_in_trans(trans, new_root);
 555
 556         ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
 557         if (ret) {
 558                 /* We potentially lose an unused inode item here */
 559                 btrfs_abort_transaction(trans, root, ret);
 560                 goto fail;
 561         }
 562
 563         /*
 564          * insert the directory item
 565          */
 566         ret = btrfs_set_inode_index(dir, &index);
 567         if (ret) {
 568                 btrfs_abort_transaction(trans, root, ret);
 569                 goto fail;
 570         }
 571
 572         ret = btrfs_insert_dir_item(trans, root,
 573                                     name, namelen, dir, &key,
 574                                     BTRFS_FT_DIR, index);
 575         if (ret) {
 576                 btrfs_abort_transaction(trans, root, ret);
 577                 goto fail;
 578         }
 579
 580         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 581         ret = btrfs_update_inode(trans, root, dir);
 582         BUG_ON(ret);
 583
 584         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 585                                  objectid, root->root_key.objectid,
 586                                  btrfs_ino(dir), index, name, namelen);
 587         BUG_ON(ret);
 588
 589         ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
 590                                   root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
 591                                   objectid);
 592         if (ret)
 593                 btrfs_abort_transaction(trans, root, ret);
 594
 595 fail:
 596         trans->block_rsv = NULL;
 597         trans->bytes_reserved = 0;
 598         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 599
 600         if (async_transid) {
 601                 *async_transid = trans->transid;
 602                 err = btrfs_commit_transaction_async(trans, root, 1);
 603                 if (err)
 604                         err = btrfs_commit_transaction(trans, root);
 605         } else {
 606                 err = btrfs_commit_transaction(trans, root);
 607         }
 608         if (err && !ret)
 609                 ret = err;
 610
 611         if (!ret) {
 612                 inode = btrfs_lookup_dentry(dir, dentry);
 613                 if (IS_ERR(inode))
 614                         return PTR_ERR(inode);
 615                 d_instantiate(dentry, inode);
 616         }
 617         return ret;
 618 }
 619
 620 static void btrfs_wait_nocow_write(struct btrfs_root *root)
 621 {
 622         s64 writers;
 623         DEFINE_WAIT(wait);
 624
 625         do {
 626                 prepare_to_wait(&root->subv_writers->wait, &wait,
 627                                 TASK_UNINTERRUPTIBLE);
 628
 629                 writers = percpu_counter_sum(&root->subv_writers->counter);
 630                 if (writers)
 631                         schedule();
 632
 633                 finish_wait(&root->subv_writers->wait, &wait);
 634         } while (writers);
 635 }
 636
 637 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 638                            struct dentry *dentry, char *name, int namelen,
 639                            u64 *async_transid, bool readonly,
 640                            struct btrfs_qgroup_inherit *inherit)
 641 {
 642         struct inode *inode;
 643         struct btrfs_pending_snapshot *pending_snapshot;
 644         struct btrfs_trans_handle *trans;
 645         int ret;
 646
 647         if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
 648                 return -EINVAL;
 649
 650         atomic_inc(&root->will_be_snapshoted);
 651         smp_mb__after_atomic();
 652         btrfs_wait_nocow_write(root);
 653
 654         ret = btrfs_start_delalloc_inodes(root, 0);
 655         if (ret)
 656                 goto out;
 657
 658         btrfs_wait_ordered_extents(root, -1);
 659
 660         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 661         if (!pending_snapshot) {
 662                 ret = -ENOMEM;
 663                 goto out;
 664         }
 665
 666         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 667                              BTRFS_BLOCK_RSV_TEMP);
 668         /*
 669          * 1 - parent dir inode
 670          * 2 - dir entries
 671          * 1 - root item
 672          * 2 - root ref/backref
 673          * 1 - root of snapshot
 674          * 1 - UUID item
 675          */
 676         ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 677                                         &pending_snapshot->block_rsv, 8,
 678                                         &pending_snapshot->qgroup_reserved,
 679                                         false);
 680         if (ret)
 681                 goto free;
 682
 683         pending_snapshot->dentry = dentry;
 684         pending_snapshot->root = root;
 685         pending_snapshot->readonly = readonly;
 686         pending_snapshot->dir = dir;
 687         pending_snapshot->inherit = inherit;
 688
 689         trans = btrfs_start_transaction(root, 0);
 690         if (IS_ERR(trans)) {
 691                 ret = PTR_ERR(trans);
 692                 goto fail;
 693         }
 694
 695         spin_lock(&root->fs_info->trans_lock);
 696         list_add(&pending_snapshot->list,
 697                  &trans->transaction->pending_snapshots);
 698         spin_unlock(&root->fs_info->trans_lock);
 699         if (async_transid) {
 700                 *async_transid = trans->transid;
 701                 ret = btrfs_commit_transaction_async(trans,
 702                                      root->fs_info->extent_root, 1);
 703                 if (ret)
 704                         ret = btrfs_commit_transaction(trans, root);
 705         } else {
 706                 ret = btrfs_commit_transaction(trans,
 707                                                root->fs_info->extent_root);
 708         }
 709         if (ret)
 710                 goto fail;
 711
 712         ret = pending_snapshot->error;
 713         if (ret)
 714                 goto fail;
 715
 716         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 717         if (ret)
 718                 goto fail;
 719
 720         /*
 721          * If orphan cleanup did remove any orphans, it means the tree was
 722          * modified and therefore the commit root is not the same as the
 723          * current root anymore. This is a problem, because send uses the
 724          * commit root and therefore can see inode items that don't exist
 725          * in the current root anymore, and for example make calls to
 726          * btrfs_iget, which will do tree lookups based on the current root
 727          * and not on the commit root. Those lookups will fail, returning a
 728          * -ESTALE error, and making send fail with that error. So make sure
 729          * a send does not see any orphans we have just removed, and that it
 730          * will see the same inodes regardless of whether a transaction
 731          * commit happened before it started (meaning that the commit root
 732          * will be the same as the current root) or not.
 733          */
 734         if (readonly && pending_snapshot->snap->node !=
 735             pending_snapshot->snap->commit_root) {
 736                 trans = btrfs_join_transaction(pending_snapshot->snap);
 737                 if (IS_ERR(trans) && PTR_ERR(trans) != -ENOENT) {
 738                         ret = PTR_ERR(trans);
 739                         goto fail;
 740                 }
 741                 if (!IS_ERR(trans)) {
 742                         ret = btrfs_commit_transaction(trans,
 743                                                        pending_snapshot->snap);
 744                         if (ret)
 745                                 goto fail;
 746                 }
 747         }
 748
 749         inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 750         if (IS_ERR(inode)) {
 751                 ret = PTR_ERR(inode);
 752                 goto fail;
 753         }
 754
 755         d_instantiate(dentry, inode);
 756         ret = 0;
 757 fail:
 758         btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
 759                                          &pending_snapshot->block_rsv,
 760                                          pending_snapshot->qgroup_reserved);
 761 free:
 762         kfree(pending_snapshot);
 763 out:
 764         atomic_dec(&root->will_be_snapshoted);
 765         return ret;
 766 }
 767
 768 /*  copy of check_sticky in fs/namei.c()
 769 * It's inline, so penalty for filesystems that don't use sticky bit is
 770 * minimal.
 771 */
 772 static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 773 {
 774         kuid_t fsuid = current_fsuid();
 775
 776         if (!(dir->i_mode & S_ISVTX))
 777                 return 0;
 778         if (uid_eq(inode->i_uid, fsuid))
 779                 return 0;
 780         if (uid_eq(dir->i_uid, fsuid))
 781                 return 0;
 782         return !capable(CAP_FOWNER);
 783 }
 784
 785 /*  copy of may_delete in fs/namei.c()
 786  *      Check whether we can remove a link victim from directory dir, check
 787  *  whether the type of victim is right.
 788  *  1. We can't do it if dir is read-only (done in permission())
 789  *  2. We should have write and exec permissions on dir
 790  *  3. We can't remove anything from append-only dir
 791  *  4. We can't do anything with immutable dir (done in permission())
 792  *  5. If the sticky bit on dir is set we should either
 793  *      a. be owner of dir, or
 794  *      b. be owner of victim, or
 795  *      c. have CAP_FOWNER capability
 796  *  6. If the victim is append-only or immutable we can't do antyhing with
 797  *     links pointing to it.
 798  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 799  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 800  *  9. We can't remove a root or mountpoint.
 801  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 802  *     nfs_async_unlink().
 803  */
 804
 805 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
 806 {
 807         int error;
 808
 809         if (!victim->d_inode)
 810                 return -ENOENT;
 811
 812         BUG_ON(victim->d_parent->d_inode != dir);
 813         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 814
 815         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 816         if (error)
 817                 return error;
 818         if (IS_APPEND(dir))
 819                 return -EPERM;
 820         if (btrfs_check_sticky(dir, victim->d_inode)||
 821                 IS_APPEND(victim->d_inode)||
 822             IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 823                 return -EPERM;
 824         if (isdir) {
 825                 if (!S_ISDIR(victim->d_inode->i_mode))
 826                         return -ENOTDIR;
 827                 if (IS_ROOT(victim))
 828                         return -EBUSY;
 829         } else if (S_ISDIR(victim->d_inode->i_mode))
 830                 return -EISDIR;
 831         if (IS_DEADDIR(dir))
 832                 return -ENOENT;
 833         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 834                 return -EBUSY;
 835         return 0;
 836 }
 837
 838 /* copy of may_create in fs/namei.c() */
 839 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 840 {
 841         if (child->d_inode)
 842                 return -EEXIST;
 843         if (IS_DEADDIR(dir))
 844                 return -ENOENT;
 845         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 846 }
 847
 848 /*
 849  * Create a new subvolume below @parent.  This is largely modeled after
 850  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 851  * inside this filesystem so it's quite a bit simpler.
 852  */
 853 static noinline int btrfs_mksubvol(struct path *parent,
 854                                    char *name, int namelen,
 855                                    struct btrfs_root *snap_src,
 856                                    u64 *async_transid, bool readonly,
 857                                    struct btrfs_qgroup_inherit *inherit)
 858 {
 859         struct inode *dir  = parent->dentry->d_inode;
 860         struct dentry *dentry;
 861         int error;
 862
 863         error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
 864         if (error == -EINTR)
 865                 return error;
 866
 867         dentry = lookup_one_len(name, parent->dentry, namelen);
 868         error = PTR_ERR(dentry);
 869         if (IS_ERR(dentry))
 870                 goto out_unlock;
 871
 872         error = -EEXIST;
 873         if (dentry->d_inode)
 874                 goto out_dput;
 875
 876         error = btrfs_may_create(dir, dentry);
 877         if (error)
 878                 goto out_dput;
 879
 880         /*
 881          * even if this name doesn't exist, we may get hash collisions.
 882          * check for them now when we can safely fail
 883          */
 884         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 885                                                dir->i_ino, name,
 886                                                namelen);
 887         if (error)
 888                 goto out_dput;
 889
 890         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 891
 892         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 893                 goto out_up_read;
 894
 895         if (snap_src) {
 896                 error = create_snapshot(snap_src, dir, dentry, name, namelen,
 897                                         async_transid, readonly, inherit);
 898         } else {
 899                 error = create_subvol(dir, dentry, name, namelen,
 900                                       async_transid, inherit);
 901         }
 902         if (!error)
 903                 fsnotify_mkdir(dir, dentry);
 904 out_up_read:
 905         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 906 out_dput:
 907         dput(dentry);
 908 out_unlock:
 909         mutex_unlock(&dir->i_mutex);
 910         return error;
 911 }
 912
 913 /*
 914  * When we're defragging a range, we don't want to kick it off again
 915  * if it is really just waiting for delalloc to send it down.
 916  * If we find a nice big extent or delalloc range for the bytes in the
 917  * file you want to defrag, we return 0 to let you know to skip this
 918  * part of the file
 919  */
 920 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
 921 {
 922         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 923         struct extent_map *em = NULL;
 924         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 925         u64 end;
 926
 927         read_lock(&em_tree->lock);
 928         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 929         read_unlock(&em_tree->lock);
 930
 931         if (em) {
 932                 end = extent_map_end(em);
 933                 free_extent_map(em);
 934                 if (end - offset > thresh)
 935                         return 0;
 936         }
 937         /* if we already have a nice delalloc here, just stop */
 938         thresh /= 2;
 939         end = count_range_bits(io_tree, &offset, offset + thresh,
 940                                thresh, EXTENT_DELALLOC, 1);
 941         if (end >= thresh)
 942                 return 0;
 943         return 1;
 944 }
 945
 946 /*
 947  * helper function to walk through a file and find extents
 948  * newer than a specific transid, and smaller than thresh.
 949  *
 950  * This is used by the defragging code to find new and small
 951  * extents
 952  */
 953 static int find_new_extents(struct btrfs_root *root,
 954                             struct inode *inode, u64 newer_than,
 955                             u64 *off, u32 thresh)
 956 {
 957         struct btrfs_path *path;
 958         struct btrfs_key min_key;
 959         struct extent_buffer *leaf;
 960         struct btrfs_file_extent_item *extent;
 961         int type;
 962         int ret;
 963         u64 ino = btrfs_ino(inode);
 964
 965         path = btrfs_alloc_path();
 966         if (!path)
 967                 return -ENOMEM;
 968
 969         min_key.objectid = ino;
 970         min_key.type = BTRFS_EXTENT_DATA_KEY;
 971         min_key.offset = *off;
 972
 973         while (1) {
 974                 ret = btrfs_search_forward(root, &min_key, path, newer_than);
 975                 if (ret != 0)
 976                         goto none;
 977 process_slot:
 978                 if (min_key.objectid != ino)
 979                         goto none;
 980                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 981                         goto none;
 982
 983                 leaf = path->nodes[0];
 984                 extent = btrfs_item_ptr(leaf, path->slots[0],
 985                                         struct btrfs_file_extent_item);
 986
 987                 type = btrfs_file_extent_type(leaf, extent);
 988                 if (type == BTRFS_FILE_EXTENT_REG &&
 989                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 990                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 991                         *off = min_key.offset;
 992                         btrfs_free_path(path);
 993                         return 0;
 994                 }
 995
 996                 path->slots[0]++;
 997                 if (path->slots[0] < btrfs_header_nritems(leaf)) {
 998                         btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
 999                         goto process_slot;
1000                 }
1001
1002                 if (min_key.offset == (u64)-1)
1003                         goto none;
1004
1005                 min_key.offset++;
1006                 btrfs_release_path(path);
1007         }
1008 none:
1009         btrfs_free_path(path);
1010         return -ENOENT;
1011 }
1012
1013 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1014 {
1015         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1016         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1017         struct extent_map *em;
1018         u64 len = PAGE_CACHE_SIZE;
1019
1020         /*
1021          * hopefully we have this extent in the tree already, try without
1022          * the full extent lock
1023          */
1024         read_lock(&em_tree->lock);
1025         em = lookup_extent_mapping(em_tree, start, len);
1026         read_unlock(&em_tree->lock);
1027
1028         if (!em) {
1029                 struct extent_state *cached = NULL;
1030                 u64 end = start + len - 1;
1031
1032                 /* get the big lock and read metadata off disk */
1033                 lock_extent_bits(io_tree, start, end, 0, &cached);
1034                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
1035                 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
1036
1037                 if (IS_ERR(em))
1038                         return NULL;
1039         }
1040
1041         return em;
1042 }
1043
1044 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1045 {
1046         struct extent_map *next;
1047         bool ret = true;
1048
1049         /* this is the last extent */
1050         if (em->start + em->len >= i_size_read(inode))
1051                 return false;
1052
1053         next = defrag_lookup_extent(inode, em->start + em->len);
1054         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1055                 ret = false;
1056         else if ((em->block_start + em->block_len == next->block_start) &&
1057                  (em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
1058                 ret = false;
1059
1060         free_extent_map(next);
1061         return ret;
1062 }
1063
1064 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1065                                u64 *last_len, u64 *skip, u64 *defrag_end,
1066                                int compress)
1067 {
1068         struct extent_map *em;
1069         int ret = 1;
1070         bool next_mergeable = true;
1071
1072         /*
1073          * make sure that once we start defragging an extent, we keep on
1074          * defragging it
1075          */
1076         if (start < *defrag_end)
1077                 return 1;
1078
1079         *skip = 0;
1080
1081         em = defrag_lookup_extent(inode, start);
1082         if (!em)
1083                 return 0;
1084
1085         /* this will cover holes, and inline extents */
1086         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1087                 ret = 0;
1088                 goto out;
1089         }
1090
1091         next_mergeable = defrag_check_next_extent(inode, em);
1092         /*
1093          * we hit a real extent, if it is big or the next extent is not a
1094          * real extent, don't bother defragging it
1095          */
1096         if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1097             (em->len >= thresh || !next_mergeable))
1098                 ret = 0;
1099 out:
1100         /*
1101          * last_len ends up being a counter of how many bytes we've defragged.
1102          * every time we choose not to defrag an extent, we reset *last_len
1103          * so that the next tiny extent will force a defrag.
1104          *
1105          * The end result of this is that tiny extents before a single big
1106          * extent will force at least part of that big extent to be defragged.
1107          */
1108         if (ret) {
1109                 *defrag_end = extent_map_end(em);
1110         } else {
1111                 *last_len = 0;
1112                 *skip = extent_map_end(em);
1113                 *defrag_end = 0;
1114         }
1115
1116         free_extent_map(em);
1117         return ret;
1118 }
1119
1120 /*
1121  * it doesn't do much good to defrag one or two pages
1122  * at a time.  This pulls in a nice chunk of pages
1123  * to COW and defrag.
1124  *
1125  * It also makes sure the delalloc code has enough
1126  * dirty data to avoid making new small extents as part
1127  * of the defrag
1128  *
1129  * It's a good idea to start RA on this range
1130  * before calling this.
1131  */
1132 static int cluster_pages_for_defrag(struct inode *inode,
1133                                     struct page **pages,
1134                                     unsigned long start_index,
1135                                     unsigned long num_pages)
1136 {
1137         unsigned long file_end;
1138         u64 isize = i_size_read(inode);
1139         u64 page_start;
1140         u64 page_end;
1141         u64 page_cnt;
1142         int ret;
1143         int i;
1144         int i_done;
1145         struct btrfs_ordered_extent *ordered;
1146         struct extent_state *cached_state = NULL;
1147         struct extent_io_tree *tree;
1148         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1149
1150         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1151         if (!isize || start_index > file_end)
1152                 return 0;
1153
1154         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1155
1156         ret = btrfs_delalloc_reserve_space(inode,
1157                                            page_cnt << PAGE_CACHE_SHIFT);
1158         if (ret)
1159                 return ret;
1160         i_done = 0;
1161         tree = &BTRFS_I(inode)->io_tree;
1162
1163         /* step one, lock all the pages */
1164         for (i = 0; i < page_cnt; i++) {
1165                 struct page *page;
1166 again:
1167                 page = find_or_create_page(inode->i_mapping,
1168                                            start_index + i, mask);
1169                 if (!page)
1170                         break;
1171
1172                 page_start = page_offset(page);
1173                 page_end = page_start + PAGE_CACHE_SIZE - 1;
1174                 while (1) {
1175                         lock_extent_bits(tree, page_start, page_end,
1176                                          0, &cached_state);
1177                         ordered = btrfs_lookup_ordered_extent(inode,
1178                                                               page_start);
1179                         unlock_extent_cached(tree, page_start, page_end,
1180                                              &cached_state, GFP_NOFS);
1181                         if (!ordered)
1182                                 break;
1183
1184                         unlock_page(page);
1185                         btrfs_start_ordered_extent(inode, ordered, 1);
1186                         btrfs_put_ordered_extent(ordered);
1187                         lock_page(page);
1188                         /*
1189                          * we unlocked the page above, so we need check if
1190                          * it was released or not.
1191                          */
1192                         if (page->mapping != inode->i_mapping) {
1193                                 unlock_page(page);
1194                                 page_cache_release(page);
1195                                 goto again;
1196                         }
1197                 }
1198
1199                 if (!PageUptodate(page)) {
1200                         btrfs_readpage(NULL, page);
1201                         lock_page(page);
1202                         if (!PageUptodate(page)) {
1203                                 unlock_page(page);
1204                                 page_cache_release(page);
1205                                 ret = -EIO;
1206                                 break;
1207                         }
1208                 }
1209
1210                 if (page->mapping != inode->i_mapping) {
1211                         unlock_page(page);
1212                         page_cache_release(page);
1213                         goto again;
1214                 }
1215
1216                 pages[i] = page;
1217                 i_done++;
1218         }
1219         if (!i_done || ret)
1220                 goto out;
1221
1222         if (!(inode->i_sb->s_flags & MS_ACTIVE))
1223                 goto out;
1224
1225         /*
1226          * so now we have a nice long stream of locked
1227          * and up to date pages, lets wait on them
1228          */
1229         for (i = 0; i < i_done; i++)
1230                 wait_on_page_writeback(pages[i]);
1231
1232         page_start = page_offset(pages[0]);
1233         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1234
1235         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1236                          page_start, page_end - 1, 0, &cached_state);
1237         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1238                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1239                           EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1240                           &cached_state, GFP_NOFS);
1241
1242         if (i_done != page_cnt) {
1243                 spin_lock(&BTRFS_I(inode)->lock);
1244                 BTRFS_I(inode)->outstanding_extents++;
1245                 spin_unlock(&BTRFS_I(inode)->lock);
1246                 btrfs_delalloc_release_space(inode,
1247                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1248         }
1249
1250
1251         set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1252                           &cached_state, GFP_NOFS);
1253
1254         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1255                              page_start, page_end - 1, &cached_state,
1256                              GFP_NOFS);
1257
1258         for (i = 0; i < i_done; i++) {
1259                 clear_page_dirty_for_io(pages[i]);
1260                 ClearPageChecked(pages[i]);
1261                 set_page_extent_mapped(pages[i]);
1262                 set_page_dirty(pages[i]);
1263                 unlock_page(pages[i]);
1264                 page_cache_release(pages[i]);
1265         }
1266         return i_done;
1267 out:
1268         for (i = 0; i < i_done; i++) {
1269                 unlock_page(pages[i]);
1270                 page_cache_release(pages[i]);
1271         }
1272         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1273         return ret;
1274
1275 }
1276
1277 int btrfs_defrag_file(struct inode *inode, struct file *file,
1278                       struct btrfs_ioctl_defrag_range_args *range,
1279                       u64 newer_than, unsigned long max_to_defrag)
1280 {
1281         struct btrfs_root *root = BTRFS_I(inode)->root;
1282         struct file_ra_state *ra = NULL;
1283         unsigned long last_index;
1284         u64 isize = i_size_read(inode);
1285         u64 last_len = 0;
1286         u64 skip = 0;
1287         u64 defrag_end = 0;
1288         u64 newer_off = range->start;
1289         unsigned long i;
1290         unsigned long ra_index = 0;
1291         int ret;
1292         int defrag_count = 0;
1293         int compress_type = BTRFS_COMPRESS_ZLIB;
1294         u32 extent_thresh = range->extent_thresh;
1295         unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1296         unsigned long cluster = max_cluster;
1297         u64 new_align = ~((u64)128 * 1024 - 1);
1298         struct page **pages = NULL;
1299
1300         if (isize == 0)
1301                 return 0;
1302
1303         if (range->start >= isize)
1304                 return -EINVAL;
1305
1306         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1307                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1308                         return -EINVAL;
1309                 if (range->compress_type)
1310                         compress_type = range->compress_type;
1311         }
1312
1313         if (extent_thresh == 0)
1314                 extent_thresh = 256 * 1024;
1315
1316         /*
1317          * if we were not given a file, allocate a readahead
1318          * context
1319          */
1320         if (!file) {
1321                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1322                 if (!ra)
1323                         return -ENOMEM;
1324                 file_ra_state_init(ra, inode->i_mapping);
1325         } else {
1326                 ra = &file->f_ra;
1327         }
1328
1329         pages = kmalloc_array(max_cluster, sizeof(struct page *),
1330                         GFP_NOFS);
1331         if (!pages) {
1332                 ret = -ENOMEM;
1333                 goto out_ra;
1334         }
1335
1336         /* find the last page to defrag */
1337         if (range->start + range->len > range->start) {
1338                 last_index = min_t(u64, isize - 1,
1339                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1340         } else {
1341                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1342         }
1343
1344         if (newer_than) {
1345                 ret = find_new_extents(root, inode, newer_than,
1346                                        &newer_off, 64 * 1024);
1347                 if (!ret) {
1348                         range->start = newer_off;
1349                         /*
1350                          * we always align our defrag to help keep
1351                          * the extents in the file evenly spaced
1352                          */
1353                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1354                 } else
1355                         goto out_ra;
1356         } else {
1357                 i = range->start >> PAGE_CACHE_SHIFT;
1358         }
1359         if (!max_to_defrag)
1360                 max_to_defrag = last_index + 1;
1361
1362         /*
1363          * make writeback starts from i, so the defrag range can be
1364          * written sequentially.
1365          */
1366         if (i < inode->i_mapping->writeback_index)
1367                 inode->i_mapping->writeback_index = i;
1368
1369         while (i <= last_index && defrag_count < max_to_defrag &&
1370                (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
1371                 /*
1372                  * make sure we stop running if someone unmounts
1373                  * the FS
1374                  */
1375                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1376                         break;
1377
1378                 if (btrfs_defrag_cancelled(root->fs_info)) {
1379                         printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1380                         ret = -EAGAIN;
1381                         break;
1382                 }
1383
1384                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1385                                          extent_thresh, &last_len, &skip,
1386                                          &defrag_end, range->flags &
1387                                          BTRFS_DEFRAG_RANGE_COMPRESS)) {
1388                         unsigned long next;
1389                         /*
1390                          * the should_defrag function tells us how much to skip
1391                          * bump our counter by the suggested amount
1392                          */
1393                         next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
1394                         i = max(i + 1, next);
1395                         continue;
1396                 }
1397
1398                 if (!newer_than) {
1399                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1400                                    PAGE_CACHE_SHIFT) - i;
1401                         cluster = min(cluster, max_cluster);
1402                 } else {
1403                         cluster = max_cluster;
1404                 }
1405
1406                 if (i + cluster > ra_index) {
1407                         ra_index = max(i, ra_index);
1408                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1409                                        cluster);
1410                         ra_index += max_cluster;
1411                 }
1412
1413                 mutex_lock(&inode->i_mutex);
1414                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1415                         BTRFS_I(inode)->force_compress = compress_type;
1416                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1417                 if (ret < 0) {
1418                         mutex_unlock(&inode->i_mutex);
1419                         goto out_ra;
1420                 }
1421
1422                 defrag_count += ret;
1423                 balance_dirty_pages_ratelimited(inode->i_mapping);
1424                 mutex_unlock(&inode->i_mutex);
1425
1426                 if (newer_than) {
1427                         if (newer_off == (u64)-1)
1428                                 break;
1429
1430                         if (ret > 0)
1431                                 i += ret;
1432
1433                         newer_off = max(newer_off + 1,
1434                                         (u64)i << PAGE_CACHE_SHIFT);
1435
1436                         ret = find_new_extents(root, inode,
1437                                                newer_than, &newer_off,
1438                                                64 * 1024);
1439                         if (!ret) {
1440                                 range->start = newer_off;
1441                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1442                         } else {
1443                                 break;
1444                         }
1445                 } else {
1446                         if (ret > 0) {
1447                                 i += ret;
1448                                 last_len += ret << PAGE_CACHE_SHIFT;
1449                         } else {
1450                                 i++;
1451                                 last_len = 0;
1452                         }
1453                 }
1454         }
1455
1456         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1457                 filemap_flush(inode->i_mapping);
1458                 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1459                              &BTRFS_I(inode)->runtime_flags))
1460                         filemap_flush(inode->i_mapping);
1461         }
1462
1463         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1464                 /* the filemap_flush will queue IO into the worker threads, but
1465                  * we have to make sure the IO is actually started and that
1466                  * ordered extents get created before we return
1467                  */
1468                 atomic_inc(&root->fs_info->async_submit_draining);
1469                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1470                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1471                         wait_event(root->fs_info->async_submit_wait,
1472                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1473                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1474                 }
1475                 atomic_dec(&root->fs_info->async_submit_draining);
1476         }
1477
1478         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1479                 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1480         }
1481
1482         ret = defrag_count;
1483
1484 out_ra:
1485         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1486                 mutex_lock(&inode->i_mutex);
1487                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1488                 mutex_unlock(&inode->i_mutex);
1489         }
1490         if (!file)
1491                 kfree(ra);
1492         kfree(pages);
1493         return ret;
1494 }
1495
1496 static noinline int btrfs_ioctl_resize(struct file *file,
1497                                         void __user *arg)
1498 {
1499         u64 new_size;
1500         u64 old_size;
1501         u64 devid = 1;
1502         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1503         struct btrfs_ioctl_vol_args *vol_args;
1504         struct btrfs_trans_handle *trans;
1505         struct btrfs_device *device = NULL;
1506         char *sizestr;
1507         char *retptr;
1508         char *devstr = NULL;
1509         int ret = 0;
1510         int mod = 0;
1511
1512         if (!capable(CAP_SYS_ADMIN))
1513                 return -EPERM;
1514
1515         ret = mnt_want_write_file(file);
1516         if (ret)
1517                 return ret;
1518
1519         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1520                         1)) {
1521                 mnt_drop_write_file(file);
1522                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1523         }
1524
1525         mutex_lock(&root->fs_info->volume_mutex);
1526         vol_args = memdup_user(arg, sizeof(*vol_args));
1527         if (IS_ERR(vol_args)) {
1528                 ret = PTR_ERR(vol_args);
1529                 goto out;
1530         }
1531
1532         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1533
1534         sizestr = vol_args->name;
1535         devstr = strchr(sizestr, ':');
1536         if (devstr) {
1537                 sizestr = devstr + 1;
1538                 *devstr = '\0';
1539                 devstr = vol_args->name;
1540                 ret = kstrtoull(devstr, 10, &devid);
1541                 if (ret)
1542                         goto out_free;
1543                 if (!devid) {
1544                         ret = -EINVAL;
1545                         goto out_free;
1546                 }
1547                 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1548         }
1549
1550         device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1551         if (!device) {
1552                 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1553                        devid);
1554                 ret = -ENODEV;
1555                 goto out_free;
1556         }
1557
1558         if (!device->writeable) {
1559                 btrfs_info(root->fs_info,
1560                            "resizer unable to apply on readonly device %llu",
1561                        devid);
1562                 ret = -EPERM;
1563                 goto out_free;
1564         }
1565
1566         if (!strcmp(sizestr, "max"))
1567                 new_size = device->bdev->bd_inode->i_size;
1568         else {
1569                 if (sizestr[0] == '-') {
1570                         mod = -1;
1571                         sizestr++;
1572                 } else if (sizestr[0] == '+') {
1573                         mod = 1;
1574                         sizestr++;
1575                 }
1576                 new_size = memparse(sizestr, &retptr);
1577                 if (*retptr != '\0' || new_size == 0) {
1578                         ret = -EINVAL;
1579                         goto out_free;
1580                 }
1581         }
1582
1583         if (device->is_tgtdev_for_dev_replace) {
1584                 ret = -EPERM;
1585                 goto out_free;
1586         }
1587
1588         old_size = btrfs_device_get_total_bytes(device);
1589
1590         if (mod < 0) {
1591                 if (new_size > old_size) {
1592                         ret = -EINVAL;
1593                         goto out_free;
1594                 }
1595                 new_size = old_size - new_size;
1596         } else if (mod > 0) {
1597                 if (new_size > ULLONG_MAX - old_size) {
1598                         ret = -ERANGE;
1599                         goto out_free;
1600                 }
1601                 new_size = old_size + new_size;
1602         }
1603
1604         if (new_size < 256 * 1024 * 1024) {
1605                 ret = -EINVAL;
1606                 goto out_free;
1607         }
1608         if (new_size > device->bdev->bd_inode->i_size) {
1609                 ret = -EFBIG;
1610                 goto out_free;
1611         }
1612
1613         do_div(new_size, root->sectorsize);
1614         new_size *= root->sectorsize;
1615
1616         printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1617                       rcu_str_deref(device->name), new_size);
1618
1619         if (new_size > old_size) {
1620                 trans = btrfs_start_transaction(root, 0);
1621                 if (IS_ERR(trans)) {
1622                         ret = PTR_ERR(trans);
1623                         goto out_free;
1624                 }
1625                 ret = btrfs_grow_device(trans, device, new_size);
1626                 btrfs_commit_transaction(trans, root);
1627         } else if (new_size < old_size) {
1628                 ret = btrfs_shrink_device(device, new_size);
1629         } /* equal, nothing need to do */
1630
1631 out_free:
1632         kfree(vol_args);
1633 out:
1634         mutex_unlock(&root->fs_info->volume_mutex);
1635         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1636         mnt_drop_write_file(file);
1637         return ret;
1638 }
1639
1640 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1641                                 char *name, unsigned long fd, int subvol,
1642                                 u64 *transid, bool readonly,
1643                                 struct btrfs_qgroup_inherit *inherit)
1644 {
1645         int namelen;
1646         int ret = 0;
1647
1648         ret = mnt_want_write_file(file);
1649         if (ret)
1650                 goto out;
1651
1652         namelen = strlen(name);
1653         if (strchr(name, '/')) {
1654                 ret = -EINVAL;
1655                 goto out_drop_write;
1656         }
1657
1658         if (name[0] == '.' &&
1659            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1660                 ret = -EEXIST;
1661                 goto out_drop_write;
1662         }
1663
1664         if (subvol) {
1665                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1666                                      NULL, transid, readonly, inherit);
1667         } else {
1668                 struct fd src = fdget(fd);
1669                 struct inode *src_inode;
1670                 if (!src.file) {
1671                         ret = -EINVAL;
1672                         goto out_drop_write;
1673                 }
1674
1675                 src_inode = file_inode(src.file);
1676                 if (src_inode->i_sb != file_inode(file)->i_sb) {
1677                         btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1678                                    "Snapshot src from another FS");
1679                         ret = -EXDEV;
1680                 } else if (!inode_owner_or_capable(src_inode)) {
1681                         /*
1682                          * Subvolume creation is not restricted, but snapshots
1683                          * are limited to own subvolumes only
1684                          */
1685                         ret = -EPERM;
1686                 } else {
1687                         ret = btrfs_mksubvol(&file->f_path, name, namelen,
1688                                              BTRFS_I(src_inode)->root,
1689                                              transid, readonly, inherit);
1690                 }
1691                 fdput(src);
1692         }
1693 out_drop_write:
1694         mnt_drop_write_file(file);
1695 out:
1696         return ret;
1697 }
1698
1699 static noinline int btrfs_ioctl_snap_create(struct file *file,
1700                                             void __user *arg, int subvol)
1701 {
1702         struct btrfs_ioctl_vol_args *vol_args;
1703         int ret;
1704
1705         vol_args = memdup_user(arg, sizeof(*vol_args));
1706         if (IS_ERR(vol_args))
1707                 return PTR_ERR(vol_args);
1708         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1709
1710         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1711                                               vol_args->fd, subvol,
1712                                               NULL, false, NULL);
1713
1714         kfree(vol_args);
1715         return ret;
1716 }
1717
1718 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1719                                                void __user *arg, int subvol)
1720 {
1721         struct btrfs_ioctl_vol_args_v2 *vol_args;
1722         int ret;
1723         u64 transid = 0;
1724         u64 *ptr = NULL;
1725         bool readonly = false;
1726         struct btrfs_qgroup_inherit *inherit = NULL;
1727
1728         vol_args = memdup_user(arg, sizeof(*vol_args));
1729         if (IS_ERR(vol_args))
1730                 return PTR_ERR(vol_args);
1731         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1732
1733         if (vol_args->flags &
1734             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1735               BTRFS_SUBVOL_QGROUP_INHERIT)) {
1736                 ret = -EOPNOTSUPP;
1737                 goto free_args;
1738         }
1739
1740         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1741                 ptr = &transid;
1742         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1743                 readonly = true;
1744         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1745                 if (vol_args->size > PAGE_CACHE_SIZE) {
1746                         ret = -EINVAL;
1747                         goto free_args;
1748                 }
1749                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1750                 if (IS_ERR(inherit)) {
1751                         ret = PTR_ERR(inherit);
1752                         goto free_args;
1753                 }
1754         }
1755
1756         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1757                                               vol_args->fd, subvol, ptr,
1758                                               readonly, inherit);
1759         if (ret)
1760                 goto free_inherit;
1761
1762         if (ptr && copy_to_user(arg +
1763                                 offsetof(struct btrfs_ioctl_vol_args_v2,
1764                                         transid),
1765                                 ptr, sizeof(*ptr)))
1766                 ret = -EFAULT;
1767
1768 free_inherit:
1769         kfree(inherit);
1770 free_args:
1771         kfree(vol_args);
1772         return ret;
1773 }
1774
1775 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1776                                                 void __user *arg)
1777 {
1778         struct inode *inode = file_inode(file);
1779         struct btrfs_root *root = BTRFS_I(inode)->root;
1780         int ret = 0;
1781         u64 flags = 0;
1782
1783         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1784                 return -EINVAL;
1785
1786         down_read(&root->fs_info->subvol_sem);
1787         if (btrfs_root_readonly(root))
1788                 flags |= BTRFS_SUBVOL_RDONLY;
1789         up_read(&root->fs_info->subvol_sem);
1790
1791         if (copy_to_user(arg, &flags, sizeof(flags)))
1792                 ret = -EFAULT;
1793
1794         return ret;
1795 }
1796
1797 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1798                                               void __user *arg)
1799 {
1800         struct inode *inode = file_inode(file);
1801         struct btrfs_root *root = BTRFS_I(inode)->root;
1802         struct btrfs_trans_handle *trans;
1803         u64 root_flags;
1804         u64 flags;
1805         int ret = 0;
1806
1807         if (!inode_owner_or_capable(inode))
1808                 return -EPERM;
1809
1810         ret = mnt_want_write_file(file);
1811         if (ret)
1812                 goto out;
1813
1814         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1815                 ret = -EINVAL;
1816                 goto out_drop_write;
1817         }
1818
1819         if (copy_from_user(&flags, arg, sizeof(flags))) {
1820                 ret = -EFAULT;
1821                 goto out_drop_write;
1822         }
1823
1824         if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1825                 ret = -EINVAL;
1826                 goto out_drop_write;
1827         }
1828
1829         if (flags & ~BTRFS_SUBVOL_RDONLY) {
1830                 ret = -EOPNOTSUPP;
1831                 goto out_drop_write;
1832         }
1833
1834         down_write(&root->fs_info->subvol_sem);
1835
1836         /* nothing to do */
1837         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1838                 goto out_drop_sem;
1839
1840         root_flags = btrfs_root_flags(&root->root_item);
1841         if (flags & BTRFS_SUBVOL_RDONLY) {
1842                 btrfs_set_root_flags(&root->root_item,
1843                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1844         } else {
1845                 /*
1846                  * Block RO -> RW transition if this subvolume is involved in
1847                  * send
1848                  */
1849                 spin_lock(&root->root_item_lock);
1850                 if (root->send_in_progress == 0) {
1851                         btrfs_set_root_flags(&root->root_item,
1852                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1853                         spin_unlock(&root->root_item_lock);
1854                 } else {
1855                         spin_unlock(&root->root_item_lock);
1856                         btrfs_warn(root->fs_info,
1857                         "Attempt to set subvolume %llu read-write during send",
1858                                         root->root_key.objectid);
1859                         ret = -EPERM;
1860                         goto out_drop_sem;
1861                 }
1862         }
1863
1864         trans = btrfs_start_transaction(root, 1);
1865         if (IS_ERR(trans)) {
1866                 ret = PTR_ERR(trans);
1867                 goto out_reset;
1868         }
1869
1870         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1871                                 &root->root_key, &root->root_item);
1872
1873         btrfs_commit_transaction(trans, root);
1874 out_reset:
1875         if (ret)
1876                 btrfs_set_root_flags(&root->root_item, root_flags);
1877 out_drop_sem:
1878         up_write(&root->fs_info->subvol_sem);
1879 out_drop_write:
1880         mnt_drop_write_file(file);
1881 out:
1882         return ret;
1883 }
1884
1885 /*
1886  * helper to check if the subvolume references other subvolumes
1887  */
1888 static noinline int may_destroy_subvol(struct btrfs_root *root)
1889 {
1890         struct btrfs_path *path;
1891         struct btrfs_dir_item *di;
1892         struct btrfs_key key;
1893         u64 dir_id;
1894         int ret;
1895
1896         path = btrfs_alloc_path();
1897         if (!path)
1898                 return -ENOMEM;
1899
1900         /* Make sure this root isn't set as the default subvol */
1901         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1902         di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1903                                    dir_id, "default", 7, 0);
1904         if (di && !IS_ERR(di)) {
1905                 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1906                 if (key.objectid == root->root_key.objectid) {
1907                         ret = -EPERM;
1908                         btrfs_err(root->fs_info, "deleting default subvolume "
1909                                   "%llu is not allowed", key.objectid);
1910                         goto out;
1911                 }
1912                 btrfs_release_path(path);
1913         }
1914
1915         key.objectid = root->root_key.objectid;
1916         key.type = BTRFS_ROOT_REF_KEY;
1917         key.offset = (u64)-1;
1918
1919         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1920                                 &key, path, 0, 0);
1921         if (ret < 0)
1922                 goto out;
1923         BUG_ON(ret == 0);
1924
1925         ret = 0;
1926         if (path->slots[0] > 0) {
1927                 path->slots[0]--;
1928                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1929                 if (key.objectid == root->root_key.objectid &&
1930                     key.type == BTRFS_ROOT_REF_KEY)
1931                         ret = -ENOTEMPTY;
1932         }
1933 out:
1934         btrfs_free_path(path);
1935         return ret;
1936 }
1937
1938 static noinline int key_in_sk(struct btrfs_key *key,
1939                               struct btrfs_ioctl_search_key *sk)
1940 {
1941         struct btrfs_key test;
1942         int ret;
1943
1944         test.objectid = sk->min_objectid;
1945         test.type = sk->min_type;
1946         test.offset = sk->min_offset;
1947
1948         ret = btrfs_comp_cpu_keys(key, &test);
1949         if (ret < 0)
1950                 return 0;
1951
1952         test.objectid = sk->max_objectid;
1953         test.type = sk->max_type;
1954         test.offset = sk->max_offset;
1955
1956         ret = btrfs_comp_cpu_keys(key, &test);
1957         if (ret > 0)
1958                 return 0;
1959         return 1;
1960 }
1961
1962 static noinline int copy_to_sk(struct btrfs_root *root,
1963                                struct btrfs_path *path,
1964                                struct btrfs_key *key,
1965                                struct btrfs_ioctl_search_key *sk,
1966                                size_t *buf_size,
1967                                char __user *ubuf,
1968                                unsigned long *sk_offset,
1969                                int *num_found)
1970 {
1971         u64 found_transid;
1972         struct extent_buffer *leaf;
1973         struct btrfs_ioctl_search_header sh;
1974         unsigned long item_off;
1975         unsigned long item_len;
1976         int nritems;
1977         int i;
1978         int slot;
1979         int ret = 0;
1980
1981         leaf = path->nodes[0];
1982         slot = path->slots[0];
1983         nritems = btrfs_header_nritems(leaf);
1984
1985         if (btrfs_header_generation(leaf) > sk->max_transid) {
1986                 i = nritems;
1987                 goto advance_key;
1988         }
1989         found_transid = btrfs_header_generation(leaf);
1990
1991         for (i = slot; i < nritems; i++) {
1992                 item_off = btrfs_item_ptr_offset(leaf, i);
1993                 item_len = btrfs_item_size_nr(leaf, i);
1994
1995                 btrfs_item_key_to_cpu(leaf, key, i);
1996                 if (!key_in_sk(key, sk))
1997                         continue;
1998
1999                 if (sizeof(sh) + item_len > *buf_size) {
2000                         if (*num_found) {
2001                                 ret = 1;
2002                                 goto out;
2003                         }
2004
2005                         /*
2006                          * return one empty item back for v1, which does not
2007                          * handle -EOVERFLOW
2008                          */
2009
2010                         *buf_size = sizeof(sh) + item_len;
2011                         item_len = 0;
2012                         ret = -EOVERFLOW;
2013                 }
2014
2015                 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2016                         ret = 1;
2017                         goto out;
2018                 }
2019
2020                 sh.objectid = key->objectid;
2021                 sh.offset = key->offset;
2022                 sh.type = key->type;
2023                 sh.len = item_len;
2024                 sh.transid = found_transid;
2025
2026                 /* copy search result header */
2027                 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
2028                         ret = -EFAULT;
2029                         goto out;
2030                 }
2031
2032                 *sk_offset += sizeof(sh);
2033
2034                 if (item_len) {
2035                         char __user *up = ubuf + *sk_offset;
2036                         /* copy the item */
2037                         if (read_extent_buffer_to_user(leaf, up,
2038                                                        item_off, item_len)) {
2039                                 ret = -EFAULT;
2040                                 goto out;
2041                         }
2042
2043                         *sk_offset += item_len;
2044                 }
2045                 (*num_found)++;
2046
2047                 if (ret) /* -EOVERFLOW from above */
2048                         goto out;
2049
2050                 if (*num_found >= sk->nr_items) {
2051                         ret = 1;
2052                         goto out;
2053                 }
2054         }
2055 advance_key:
2056         ret = 0;
2057         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2058                 key->offset++;
2059         else if (key->type < (u8)-1 && key->type < sk->max_type) {
2060                 key->offset = 0;
2061                 key->type++;
2062         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2063                 key->offset = 0;
2064                 key->type = 0;
2065                 key->objectid++;
2066         } else
2067                 ret = 1;
2068 out:
2069         /*
2070          *  0: all items from this leaf copied, continue with next
2071          *  1: * more items can be copied, but unused buffer is too small
2072          *     * all items were found
2073          *     Either way, it will stops the loop which iterates to the next
2074          *     leaf
2075          *  -EOVERFLOW: item was to large for buffer
2076          *  -EFAULT: could not copy extent buffer back to userspace
2077          */
2078         return ret;
2079 }
2080
2081 static noinline int search_ioctl(struct inode *inode,
2082                                  struct btrfs_ioctl_search_key *sk,
2083                                  size_t *buf_size,
2084                                  char __user *ubuf)
2085 {
2086         struct btrfs_root *root;
2087         struct btrfs_key key;
2088         struct btrfs_path *path;
2089         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2090         int ret;
2091         int num_found = 0;
2092         unsigned long sk_offset = 0;
2093
2094         if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2095                 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2096                 return -EOVERFLOW;
2097         }
2098
2099         path = btrfs_alloc_path();
2100         if (!path)
2101                 return -ENOMEM;
2102
2103         if (sk->tree_id == 0) {
2104                 /* search the root of the inode that was passed */
2105                 root = BTRFS_I(inode)->root;
2106         } else {
2107                 key.objectid = sk->tree_id;
2108                 key.type = BTRFS_ROOT_ITEM_KEY;
2109                 key.offset = (u64)-1;
2110                 root = btrfs_read_fs_root_no_name(info, &key);
2111                 if (IS_ERR(root)) {
2112                         printk(KERN_ERR "BTRFS: could not find root %llu\n",
2113                                sk->tree_id);
2114                         btrfs_free_path(path);
2115                         return -ENOENT;
2116                 }
2117         }
2118
2119         key.objectid = sk->min_objectid;
2120         key.type = sk->min_type;
2121         key.offset = sk->min_offset;
2122
2123         while (1) {
2124                 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2125                 if (ret != 0) {
2126                         if (ret > 0)
2127                                 ret = 0;
2128                         goto err;
2129                 }
2130                 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2131                                  &sk_offset, &num_found);
2132                 btrfs_release_path(path);
2133                 if (ret)
2134                         break;
2135
2136         }
2137         if (ret > 0)
2138                 ret = 0;
2139 err:
2140         sk->nr_items = num_found;
2141         btrfs_free_path(path);
2142         return ret;
2143 }
2144
2145 static noinline int btrfs_ioctl_tree_search(struct file *file,
2146                                            void __user *argp)
2147 {
2148         struct btrfs_ioctl_search_args __user *uargs;
2149         struct btrfs_ioctl_search_key sk;
2150         struct inode *inode;
2151         int ret;
2152         size_t buf_size;
2153
2154         if (!capable(CAP_SYS_ADMIN))
2155                 return -EPERM;
2156
2157         uargs = (struct btrfs_ioctl_search_args __user *)argp;
2158
2159         if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2160                 return -EFAULT;
2161
2162         buf_size = sizeof(uargs->buf);
2163
2164         inode = file_inode(file);
2165         ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2166
2167         /*
2168          * In the origin implementation an overflow is handled by returning a
2169          * search header with a len of zero, so reset ret.
2170          */
2171         if (ret == -EOVERFLOW)
2172                 ret = 0;
2173
2174         if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2175                 ret = -EFAULT;
2176         return ret;
2177 }
2178
2179 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2180                                                void __user *argp)
2181 {
2182         struct btrfs_ioctl_search_args_v2 __user *uarg;
2183         struct btrfs_ioctl_search_args_v2 args;
2184         struct inode *inode;
2185         int ret;
2186         size_t buf_size;
2187         const size_t buf_limit = 16 * 1024 * 1024;
2188
2189         if (!capable(CAP_SYS_ADMIN))
2190                 return -EPERM;
2191
2192         /* copy search header and buffer size */
2193         uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2194         if (copy_from_user(&args, uarg, sizeof(args)))
2195                 return -EFAULT;
2196
2197         buf_size = args.buf_size;
2198
2199         if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2200                 return -EOVERFLOW;
2201
2202         /* limit result size to 16MB */
2203         if (buf_size > buf_limit)
2204                 buf_size = buf_limit;
2205
2206         inode = file_inode(file);
2207         ret = search_ioctl(inode, &args.key, &buf_size,
2208                            (char *)(&uarg->buf[0]));
2209         if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2210                 ret = -EFAULT;
2211         else if (ret == -EOVERFLOW &&
2212                 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2213                 ret = -EFAULT;
2214
2215         return ret;
2216 }
2217
2218 /*
2219  * Search INODE_REFs to identify path name of 'dirid' directory
2220  * in a 'tree_id' tree. and sets path name to 'name'.
2221  */
2222 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2223                                 u64 tree_id, u64 dirid, char *name)
2224 {
2225         struct btrfs_root *root;
2226         struct btrfs_key key;
2227         char *ptr;
2228         int ret = -1;
2229         int slot;
2230         int len;
2231         int total_len = 0;
2232         struct btrfs_inode_ref *iref;
2233         struct extent_buffer *l;
2234         struct btrfs_path *path;
2235
2236         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2237                 name[0]='\0';
2238                 return 0;
2239         }
2240
2241         path = btrfs_alloc_path();
2242         if (!path)
2243                 return -ENOMEM;
2244
2245         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2246
2247         key.objectid = tree_id;
2248         key.type = BTRFS_ROOT_ITEM_KEY;
2249         key.offset = (u64)-1;
2250         root = btrfs_read_fs_root_no_name(info, &key);
2251         if (IS_ERR(root)) {
2252                 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2253                 ret = -ENOENT;
2254                 goto out;
2255         }
2256
2257         key.objectid = dirid;
2258         key.type = BTRFS_INODE_REF_KEY;
2259         key.offset = (u64)-1;
2260
2261         while (1) {
2262                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2263                 if (ret < 0)
2264                         goto out;
2265                 else if (ret > 0) {
2266                         ret = btrfs_previous_item(root, path, dirid,
2267                                                   BTRFS_INODE_REF_KEY);
2268                         if (ret < 0)
2269                                 goto out;
2270                         else if (ret > 0) {
2271                                 ret = -ENOENT;
2272                                 goto out;
2273                         }
2274                 }
2275
2276                 l = path->nodes[0];
2277                 slot = path->slots[0];
2278                 btrfs_item_key_to_cpu(l, &key, slot);
2279
2280                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2281                 len = btrfs_inode_ref_name_len(l, iref);
2282                 ptr -= len + 1;
2283                 total_len += len + 1;
2284                 if (ptr < name) {
2285                         ret = -ENAMETOOLONG;
2286                         goto out;
2287                 }
2288
2289                 *(ptr + len) = '/';
2290                 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2291
2292                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2293                         break;
2294
2295                 btrfs_release_path(path);
2296                 key.objectid = key.offset;
2297                 key.offset = (u64)-1;
2298                 dirid = key.objectid;
2299         }
2300         memmove(name, ptr, total_len);
2301         name[total_len] = '\0';
2302         ret = 0;
2303 out:
2304         btrfs_free_path(path);
2305         return ret;
2306 }
2307
2308 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2309                                            void __user *argp)
2310 {
2311          struct btrfs_ioctl_ino_lookup_args *args;
2312          struct inode *inode;
2313          int ret;
2314
2315         if (!capable(CAP_SYS_ADMIN))
2316                 return -EPERM;
2317
2318         args = memdup_user(argp, sizeof(*args));
2319         if (IS_ERR(args))
2320                 return PTR_ERR(args);
2321
2322         inode = file_inode(file);
2323
2324         if (args->treeid == 0)
2325                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2326
2327         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2328                                         args->treeid, args->objectid,
2329                                         args->name);
2330
2331         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2332                 ret = -EFAULT;
2333
2334         kfree(args);
2335         return ret;
2336 }
2337
2338 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2339                                              void __user *arg)
2340 {
2341         struct dentry *parent = file->f_path.dentry;
2342         struct dentry *dentry;
2343         struct inode *dir = parent->d_inode;
2344         struct inode *inode;
2345         struct btrfs_root *root = BTRFS_I(dir)->root;
2346         struct btrfs_root *dest = NULL;
2347         struct btrfs_ioctl_vol_args *vol_args;
2348         struct btrfs_trans_handle *trans;
2349         struct btrfs_block_rsv block_rsv;
2350         u64 root_flags;
2351         u64 qgroup_reserved;
2352         int namelen;
2353         int ret;
2354         int err = 0;
2355
2356         vol_args = memdup_user(arg, sizeof(*vol_args));
2357         if (IS_ERR(vol_args))
2358                 return PTR_ERR(vol_args);
2359
2360         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2361         namelen = strlen(vol_args->name);
2362         if (strchr(vol_args->name, '/') ||
2363             strncmp(vol_args->name, "..", namelen) == 0) {
2364                 err = -EINVAL;
2365                 goto out;
2366         }
2367
2368         err = mnt_want_write_file(file);
2369         if (err)
2370                 goto out;
2371
2372
2373         err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2374         if (err == -EINTR)
2375                 goto out_drop_write;
2376         dentry = lookup_one_len(vol_args->name, parent, namelen);
2377         if (IS_ERR(dentry)) {
2378                 err = PTR_ERR(dentry);
2379                 goto out_unlock_dir;
2380         }
2381
2382         if (!dentry->d_inode) {
2383                 err = -ENOENT;
2384                 goto out_dput;
2385         }
2386
2387         inode = dentry->d_inode;
2388         dest = BTRFS_I(inode)->root;
2389         if (!capable(CAP_SYS_ADMIN)) {
2390                 /*
2391                  * Regular user.  Only allow this with a special mount
2392                  * option, when the user has write+exec access to the
2393                  * subvol root, and when rmdir(2) would have been
2394                  * allowed.
2395                  *
2396                  * Note that this is _not_ check that the subvol is
2397                  * empty or doesn't contain data that we wouldn't
2398                  * otherwise be able to delete.
2399                  *
2400                  * Users who want to delete empty subvols should try
2401                  * rmdir(2).
2402                  */
2403                 err = -EPERM;
2404                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2405                         goto out_dput;
2406
2407                 /*
2408                  * Do not allow deletion if the parent dir is the same
2409                  * as the dir to be deleted.  That means the ioctl
2410                  * must be called on the dentry referencing the root
2411                  * of the subvol, not a random directory contained
2412                  * within it.
2413                  */
2414                 err = -EINVAL;
2415                 if (root == dest)
2416                         goto out_dput;
2417
2418                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2419                 if (err)
2420                         goto out_dput;
2421         }
2422
2423         /* check if subvolume may be deleted by a user */
2424         err = btrfs_may_delete(dir, dentry, 1);
2425         if (err)
2426                 goto out_dput;
2427
2428         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2429                 err = -EINVAL;
2430                 goto out_dput;
2431         }
2432
2433         mutex_lock(&inode->i_mutex);
2434
2435         /*
2436          * Don't allow to delete a subvolume with send in progress. This is
2437          * inside the i_mutex so the error handling that has to drop the bit
2438          * again is not run concurrently.
2439          */
2440         spin_lock(&dest->root_item_lock);
2441         root_flags = btrfs_root_flags(&dest->root_item);
2442         if (dest->send_in_progress == 0) {
2443                 btrfs_set_root_flags(&dest->root_item,
2444                                 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2445                 spin_unlock(&dest->root_item_lock);
2446         } else {
2447                 spin_unlock(&dest->root_item_lock);
2448                 btrfs_warn(root->fs_info,
2449                         "Attempt to delete subvolume %llu during send",
2450                         dest->root_key.objectid);
2451                 err = -EPERM;
2452                 goto out_dput;
2453         }
2454
2455         d_invalidate(dentry);
2456
2457         down_write(&root->fs_info->subvol_sem);
2458
2459         err = may_destroy_subvol(dest);
2460         if (err)
2461                 goto out_up_write;
2462
2463         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2464         /*
2465          * One for dir inode, two for dir entries, two for root
2466          * ref/backref.
2467          */
2468         err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2469                                                5, &qgroup_reserved, true);
2470         if (err)
2471                 goto out_up_write;
2472
2473         trans = btrfs_start_transaction(root, 0);
2474         if (IS_ERR(trans)) {
2475                 err = PTR_ERR(trans);
2476                 goto out_release;
2477         }
2478         trans->block_rsv = &block_rsv;
2479         trans->bytes_reserved = block_rsv.size;
2480
2481         ret = btrfs_unlink_subvol(trans, root, dir,
2482                                 dest->root_key.objectid,
2483                                 dentry->d_name.name,
2484                                 dentry->d_name.len);
2485         if (ret) {
2486                 err = ret;
2487                 btrfs_abort_transaction(trans, root, ret);
2488                 goto out_end_trans;
2489         }
2490
2491         btrfs_record_root_in_trans(trans, dest);
2492
2493         memset(&dest->root_item.drop_progress, 0,
2494                 sizeof(dest->root_item.drop_progress));
2495         dest->root_item.drop_level = 0;
2496         btrfs_set_root_refs(&dest->root_item, 0);
2497
2498         if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2499                 ret = btrfs_insert_orphan_item(trans,
2500                                         root->fs_info->tree_root,
2501                                         dest->root_key.objectid);
2502                 if (ret) {
2503                         btrfs_abort_transaction(trans, root, ret);
2504                         err = ret;
2505                         goto out_end_trans;
2506                 }
2507         }
2508
2509         ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2510                                   dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2511                                   dest->root_key.objectid);
2512         if (ret && ret != -ENOENT) {
2513                 btrfs_abort_transaction(trans, root, ret);
2514                 err = ret;
2515                 goto out_end_trans;
2516         }
2517         if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2518                 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2519                                           dest->root_item.received_uuid,
2520                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2521                                           dest->root_key.objectid);
2522                 if (ret && ret != -ENOENT) {
2523                         btrfs_abort_transaction(trans, root, ret);
2524                         err = ret;
2525                         goto out_end_trans;
2526                 }
2527         }
2528
2529 out_end_trans:
2530         trans->block_rsv = NULL;
2531         trans->bytes_reserved = 0;
2532         ret = btrfs_end_transaction(trans, root);
2533         if (ret && !err)
2534                 err = ret;
2535         inode->i_flags |= S_DEAD;
2536 out_release:
2537         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2538 out_up_write:
2539         up_write(&root->fs_info->subvol_sem);
2540         if (err) {
2541                 spin_lock(&dest->root_item_lock);
2542                 root_flags = btrfs_root_flags(&dest->root_item);
2543                 btrfs_set_root_flags(&dest->root_item,
2544                                 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2545                 spin_unlock(&dest->root_item_lock);
2546         }
2547         mutex_unlock(&inode->i_mutex);
2548         if (!err) {
2549                 shrink_dcache_sb(root->fs_info->sb);
2550                 btrfs_invalidate_inodes(dest);
2551                 d_delete(dentry);
2552                 ASSERT(dest->send_in_progress == 0);
2553
2554                 /* the last ref */
2555                 if (dest->ino_cache_inode) {
2556                         iput(dest->ino_cache_inode);
2557                         dest->ino_cache_inode = NULL;
2558                 }
2559         }
2560 out_dput:
2561         dput(dentry);
2562 out_unlock_dir:
2563         mutex_unlock(&dir->i_mutex);
2564 out_drop_write:
2565         mnt_drop_write_file(file);
2566 out:
2567         kfree(vol_args);
2568         return err;
2569 }
2570
2571 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2572 {
2573         struct inode *inode = file_inode(file);
2574         struct btrfs_root *root = BTRFS_I(inode)->root;
2575         struct btrfs_ioctl_defrag_range_args *range;
2576         int ret;
2577
2578         ret = mnt_want_write_file(file);
2579         if (ret)
2580                 return ret;
2581
2582         if (btrfs_root_readonly(root)) {
2583                 ret = -EROFS;
2584                 goto out;
2585         }
2586
2587         switch (inode->i_mode & S_IFMT) {
2588         case S_IFDIR:
2589                 if (!capable(CAP_SYS_ADMIN)) {
2590                         ret = -EPERM;
2591                         goto out;
2592                 }
2593                 ret = btrfs_defrag_root(root);
2594                 if (ret)
2595                         goto out;
2596                 ret = btrfs_defrag_root(root->fs_info->extent_root);
2597                 break;
2598         case S_IFREG:
2599                 if (!(file->f_mode & FMODE_WRITE)) {
2600                         ret = -EINVAL;
2601                         goto out;
2602                 }
2603
2604                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2605                 if (!range) {
2606                         ret = -ENOMEM;
2607                         goto out;
2608                 }
2609
2610                 if (argp) {
2611                         if (copy_from_user(range, argp,
2612                                            sizeof(*range))) {
2613                                 ret = -EFAULT;
2614                                 kfree(range);
2615                                 goto out;
2616                         }
2617                         /* compression requires us to start the IO */
2618                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2619                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2620                                 range->extent_thresh = (u32)-1;
2621                         }
2622                 } else {
2623                         /* the rest are all set to zero by kzalloc */
2624                         range->len = (u64)-1;
2625                 }
2626                 ret = btrfs_defrag_file(file_inode(file), file,
2627                                         range, 0, 0);
2628                 if (ret > 0)
2629                         ret = 0;
2630                 kfree(range);
2631                 break;
2632         default:
2633                 ret = -EINVAL;
2634         }
2635 out:
2636         mnt_drop_write_file(file);
2637         return ret;
2638 }
2639
2640 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2641 {
2642         struct btrfs_ioctl_vol_args *vol_args;
2643         int ret;
2644
2645         if (!capable(CAP_SYS_ADMIN))
2646                 return -EPERM;
2647
2648         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2649                         1)) {
2650                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2651         }
2652
2653         mutex_lock(&root->fs_info->volume_mutex);
2654         vol_args = memdup_user(arg, sizeof(*vol_args));
2655         if (IS_ERR(vol_args)) {
2656                 ret = PTR_ERR(vol_args);
2657                 goto out;
2658         }
2659
2660         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2661         ret = btrfs_init_new_device(root, vol_args->name);
2662
2663         if (!ret)
2664                 btrfs_info(root->fs_info, "disk added %s",vol_args->name);
2665
2666         kfree(vol_args);
2667 out:
2668         mutex_unlock(&root->fs_info->volume_mutex);
2669         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2670         return ret;
2671 }
2672
2673 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2674 {
2675         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2676         struct btrfs_ioctl_vol_args *vol_args;
2677         int ret;
2678
2679         if (!capable(CAP_SYS_ADMIN))
2680                 return -EPERM;
2681
2682         ret = mnt_want_write_file(file);
2683         if (ret)
2684                 return ret;
2685
2686         vol_args = memdup_user(arg, sizeof(*vol_args));
2687         if (IS_ERR(vol_args)) {
2688                 ret = PTR_ERR(vol_args);
2689                 goto err_drop;
2690         }
2691
2692         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2693
2694         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2695                         1)) {
2696                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2697                 goto out;
2698         }
2699
2700         mutex_lock(&root->fs_info->volume_mutex);
2701         ret = btrfs_rm_device(root, vol_args->name);
2702         mutex_unlock(&root->fs_info->volume_mutex);
2703         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2704
2705         if (!ret)
2706                 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
2707
2708 out:
2709         kfree(vol_args);
2710 err_drop:
2711         mnt_drop_write_file(file);
2712         return ret;
2713 }
2714
2715 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2716 {
2717         struct btrfs_ioctl_fs_info_args *fi_args;
2718         struct btrfs_device *device;
2719         struct btrfs_device *next;
2720         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2721         int ret = 0;
2722
2723         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2724         if (!fi_args)
2725                 return -ENOMEM;
2726
2727         mutex_lock(&fs_devices->device_list_mutex);
2728         fi_args->num_devices = fs_devices->num_devices;
2729         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2730
2731         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2732                 if (device->devid > fi_args->max_id)
2733                         fi_args->max_id = device->devid;
2734         }
2735         mutex_unlock(&fs_devices->device_list_mutex);
2736
2737         fi_args->nodesize = root->fs_info->super_copy->nodesize;
2738         fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2739         fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2740
2741         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2742                 ret = -EFAULT;
2743
2744         kfree(fi_args);
2745         return ret;
2746 }
2747
2748 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2749 {
2750         struct btrfs_ioctl_dev_info_args *di_args;
2751         struct btrfs_device *dev;
2752         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2753         int ret = 0;
2754         char *s_uuid = NULL;
2755
2756         di_args = memdup_user(arg, sizeof(*di_args));
2757         if (IS_ERR(di_args))
2758                 return PTR_ERR(di_args);
2759
2760         if (!btrfs_is_empty_uuid(di_args->uuid))
2761                 s_uuid = di_args->uuid;
2762
2763         mutex_lock(&fs_devices->device_list_mutex);
2764         dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2765
2766         if (!dev) {
2767                 ret = -ENODEV;
2768                 goto out;
2769         }
2770
2771         di_args->devid = dev->devid;
2772         di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2773         di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2774         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2775         if (dev->name) {
2776                 struct rcu_string *name;
2777
2778                 rcu_read_lock();
2779                 name = rcu_dereference(dev->name);
2780                 strncpy(di_args->path, name->str, sizeof(di_args->path));
2781                 rcu_read_unlock();
2782                 di_args->path[sizeof(di_args->path) - 1] = 0;
2783         } else {
2784                 di_args->path[0] = '\0';
2785         }
2786
2787 out:
2788         mutex_unlock(&fs_devices->device_list_mutex);
2789         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2790                 ret = -EFAULT;
2791
2792         kfree(di_args);
2793         return ret;
2794 }
2795
2796 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2797 {
2798         struct page *page;
2799         pgoff_t index;
2800         struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2801
2802         index = off >> PAGE_CACHE_SHIFT;
2803
2804         page = grab_cache_page(inode->i_mapping, index);
2805         if (!page)
2806                 return NULL;
2807
2808         if (!PageUptodate(page)) {
2809                 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2810                                                  0))
2811                         return NULL;
2812                 lock_page(page);
2813                 if (!PageUptodate(page)) {
2814                         unlock_page(page);
2815                         page_cache_release(page);
2816                         return NULL;
2817                 }
2818         }
2819         unlock_page(page);
2820
2821         return page;
2822 }
2823
2824 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2825 {
2826         /* do any pending delalloc/csum calc on src, one way or
2827            another, and lock file content */
2828         while (1) {
2829                 struct btrfs_ordered_extent *ordered;
2830                 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2831                 ordered = btrfs_lookup_first_ordered_extent(inode,
2832                                                             off + len - 1);
2833                 if ((!ordered ||
2834                      ordered->file_offset + ordered->len <= off ||
2835                      ordered->file_offset >= off + len) &&
2836                     !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2837                                     off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2838                         if (ordered)
2839                                 btrfs_put_ordered_extent(ordered);
2840                         break;
2841                 }
2842                 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2843                 if (ordered)
2844                         btrfs_put_ordered_extent(ordered);
2845                 btrfs_wait_ordered_range(inode, off, len);
2846         }
2847 }
2848
2849 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2850                                 struct inode *inode2, u64 loff2, u64 len)
2851 {
2852         unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2853         unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2854
2855         mutex_unlock(&inode1->i_mutex);
2856         mutex_unlock(&inode2->i_mutex);
2857 }
2858
2859 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2860                               struct inode *inode2, u64 loff2, u64 len)
2861 {
2862         if (inode1 < inode2) {
2863                 swap(inode1, inode2);
2864                 swap(loff1, loff2);
2865         }
2866
2867         mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2868         lock_extent_range(inode1, loff1, len);
2869         if (inode1 != inode2) {
2870                 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2871                 lock_extent_range(inode2, loff2, len);
2872         }
2873 }
2874
2875 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2876                           u64 dst_loff, u64 len)
2877 {
2878         int ret = 0;
2879         struct page *src_page, *dst_page;
2880         unsigned int cmp_len = PAGE_CACHE_SIZE;
2881         void *addr, *dst_addr;
2882
2883         while (len) {
2884                 if (len < PAGE_CACHE_SIZE)
2885                         cmp_len = len;
2886
2887                 src_page = extent_same_get_page(src, loff);
2888                 if (!src_page)
2889                         return -EINVAL;
2890                 dst_page = extent_same_get_page(dst, dst_loff);
2891                 if (!dst_page) {
2892                         page_cache_release(src_page);
2893                         return -EINVAL;
2894                 }
2895                 addr = kmap_atomic(src_page);
2896                 dst_addr = kmap_atomic(dst_page);
2897
2898                 flush_dcache_page(src_page);
2899                 flush_dcache_page(dst_page);
2900
2901                 if (memcmp(addr, dst_addr, cmp_len))
2902                         ret = BTRFS_SAME_DATA_DIFFERS;
2903
2904                 kunmap_atomic(addr);
2905                 kunmap_atomic(dst_addr);
2906                 page_cache_release(src_page);
2907                 page_cache_release(dst_page);
2908
2909                 if (ret)
2910                         break;
2911
2912                 loff += cmp_len;
2913                 dst_loff += cmp_len;
2914                 len -= cmp_len;
2915         }
2916
2917         return ret;
2918 }
2919
2920 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2921 {
2922         u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2923
2924         if (off + len > inode->i_size || off + len < off)
2925                 return -EINVAL;
2926         /* Check that we are block aligned - btrfs_clone() requires this */
2927         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2928                 return -EINVAL;
2929
2930         return 0;
2931 }
2932
2933 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2934                              struct inode *dst, u64 dst_loff)
2935 {
2936         int ret;
2937
2938         /*
2939          * btrfs_clone() can't handle extents in the same file
2940          * yet. Once that works, we can drop this check and replace it
2941          * with a check for the same inode, but overlapping extents.
2942          */
2943         if (src == dst)
2944                 return -EINVAL;
2945
2946         btrfs_double_lock(src, loff, dst, dst_loff, len);
2947
2948         ret = extent_same_check_offsets(src, loff, len);
2949         if (ret)
2950                 goto out_unlock;
2951
2952         ret = extent_same_check_offsets(dst, dst_loff, len);
2953         if (ret)
2954                 goto out_unlock;
2955
2956         /* don't make the dst file partly checksummed */
2957         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2958             (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2959                 ret = -EINVAL;
2960                 goto out_unlock;
2961         }
2962
2963         ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2964         if (ret == 0)
2965                 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2966
2967 out_unlock:
2968         btrfs_double_unlock(src, loff, dst, dst_loff, len);
2969
2970         return ret;
2971 }
2972
2973 #define BTRFS_MAX_DEDUPE_LEN    (16 * 1024 * 1024)
2974
2975 static long btrfs_ioctl_file_extent_same(struct file *file,
2976                         struct btrfs_ioctl_same_args __user *argp)
2977 {
2978         struct btrfs_ioctl_same_args *same;
2979         struct btrfs_ioctl_same_extent_info *info;
2980         struct inode *src = file_inode(file);
2981         u64 off;
2982         u64 len;
2983         int i;
2984         int ret;
2985         unsigned long size;
2986         u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2987         bool is_admin = capable(CAP_SYS_ADMIN);
2988         u16 count;
2989
2990         if (!(file->f_mode & FMODE_READ))
2991                 return -EINVAL;
2992
2993         ret = mnt_want_write_file(file);
2994         if (ret)
2995                 return ret;
2996
2997         if (get_user(count, &argp->dest_count)) {
2998                 ret = -EFAULT;
2999                 goto out;
3000         }
3001
3002         size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
3003
3004         same = memdup_user(argp, size);
3005
3006         if (IS_ERR(same)) {
3007                 ret = PTR_ERR(same);
3008                 goto out;
3009         }
3010
3011         off = same->logical_offset;
3012         len = same->length;
3013
3014         /*
3015          * Limit the total length we will dedupe for each operation.
3016          * This is intended to bound the total time spent in this
3017          * ioctl to something sane.
3018          */
3019         if (len > BTRFS_MAX_DEDUPE_LEN)
3020                 len = BTRFS_MAX_DEDUPE_LEN;
3021
3022         if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
3023                 /*
3024                  * Btrfs does not support blocksize < page_size. As a
3025                  * result, btrfs_cmp_data() won't correctly handle
3026                  * this situation without an update.
3027                  */
3028                 ret = -EINVAL;
3029                 goto out;
3030         }
3031
3032         ret = -EISDIR;
3033         if (S_ISDIR(src->i_mode))
3034                 goto out;
3035
3036         ret = -EACCES;
3037         if (!S_ISREG(src->i_mode))
3038                 goto out;
3039
3040         /* pre-format output fields to sane values */
3041         for (i = 0; i < count; i++) {
3042                 same->info[i].bytes_deduped = 0ULL;
3043                 same->info[i].status = 0;
3044         }
3045
3046         for (i = 0, info = same->info; i < count; i++, info++) {
3047                 struct inode *dst;
3048                 struct fd dst_file = fdget(info->fd);
3049                 if (!dst_file.file) {
3050                         info->status = -EBADF;
3051                         continue;
3052                 }
3053                 dst = file_inode(dst_file.file);
3054
3055                 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3056                         info->status = -EINVAL;
3057                 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3058                         info->status = -EXDEV;
3059                 } else if (S_ISDIR(dst->i_mode)) {
3060                         info->status = -EISDIR;
3061                 } else if (!S_ISREG(dst->i_mode)) {
3062                         info->status = -EACCES;
3063                 } else {
3064                         info->status = btrfs_extent_same(src, off, len, dst,
3065                                                         info->logical_offset);
3066                         if (info->status == 0)
3067                                 info->bytes_deduped += len;
3068                 }
3069                 fdput(dst_file);
3070         }
3071
3072         ret = copy_to_user(argp, same, size);
3073         if (ret)
3074                 ret = -EFAULT;
3075
3076 out:
3077         mnt_drop_write_file(file);
3078         return ret;
3079 }
3080
3081 /* Helper to check and see if this root currently has a ref on the given disk
3082  * bytenr.  If it does then we need to update the quota for this root.  This
3083  * doesn't do anything if quotas aren't enabled.
3084  */
3085 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3086                      u64 disko)
3087 {
3088         struct seq_list tree_mod_seq_elem = {};
3089         struct ulist *roots;
3090         struct ulist_iterator uiter;
3091         struct ulist_node *root_node = NULL;
3092         int ret;
3093
3094         if (!root->fs_info->quota_enabled)
3095                 return 1;
3096
3097         btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3098         ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3099                                    tree_mod_seq_elem.seq, &roots);
3100         if (ret < 0)
3101                 goto out;
3102         ret = 0;
3103         ULIST_ITER_INIT(&uiter);
3104         while ((root_node = ulist_next(roots, &uiter))) {
3105                 if (root_node->val == root->objectid) {
3106                         ret = 1;
3107                         break;
3108                 }
3109         }
3110         ulist_free(roots);
3111 out:
3112         btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3113         return ret;
3114 }
3115
3116 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3117                                      struct inode *inode,
3118                                      u64 endoff,
3119                                      const u64 destoff,
3120                                      const u64 olen)
3121 {
3122         struct btrfs_root *root = BTRFS_I(inode)->root;
3123         int ret;
3124
3125         inode_inc_iversion(inode);
3126         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3127         /*
3128          * We round up to the block size at eof when determining which
3129          * extents to clone above, but shouldn't round up the file size.
3130          */
3131         if (endoff > destoff + olen)
3132                 endoff = destoff + olen;
3133         if (endoff > inode->i_size)
3134                 btrfs_i_size_write(inode, endoff);
3135
3136         ret = btrfs_update_inode(trans, root, inode);
3137         if (ret) {
3138                 btrfs_abort_transaction(trans, root, ret);
3139                 btrfs_end_transaction(trans, root);
3140                 goto out;
3141         }
3142         ret = btrfs_end_transaction(trans, root);
3143 out:
3144         return ret;
3145 }
3146
3147 static void clone_update_extent_map(struct inode *inode,
3148                                     const struct btrfs_trans_handle *trans,
3149                                     const struct btrfs_path *path,
3150                                     const u64 hole_offset,
3151                                     const u64 hole_len)
3152 {
3153         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3154         struct extent_map *em;
3155         int ret;
3156
3157         em = alloc_extent_map();
3158         if (!em) {
3159                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3160                         &BTRFS_I(inode)->runtime_flags);
3161                 return;
3162         }
3163
3164         if (path) {
3165                 struct btrfs_file_extent_item *fi;
3166
3167                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3168                                     struct btrfs_file_extent_item);
3169                 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3170                 em->generation = -1;
3171                 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3172                     BTRFS_FILE_EXTENT_INLINE)
3173                         set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3174                                 &BTRFS_I(inode)->runtime_flags);
3175         } else {
3176                 em->start = hole_offset;
3177                 em->len = hole_len;
3178                 em->ram_bytes = em->len;
3179                 em->orig_start = hole_offset;
3180                 em->block_start = EXTENT_MAP_HOLE;
3181                 em->block_len = 0;
3182                 em->orig_block_len = 0;
3183                 em->compress_type = BTRFS_COMPRESS_NONE;
3184                 em->generation = trans->transid;
3185         }
3186
3187         while (1) {
3188                 write_lock(&em_tree->lock);
3189                 ret = add_extent_mapping(em_tree, em, 1);
3190                 write_unlock(&em_tree->lock);
3191                 if (ret != -EEXIST) {
3192                         free_extent_map(em);
3193                         break;
3194                 }
3195                 btrfs_drop_extent_cache(inode, em->start,
3196                                         em->start + em->len - 1, 0);
3197         }
3198
3199         if (ret)
3200                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3201                         &BTRFS_I(inode)->runtime_flags);
3202 }
3203
3204 /**
3205  * btrfs_clone() - clone a range from inode file to another
3206  *
3207  * @src: Inode to clone from
3208  * @inode: Inode to clone to
3209  * @off: Offset within source to start clone from
3210  * @olen: Original length, passed by user, of range to clone
3211  * @olen_aligned: Block-aligned value of olen, extent_same uses
3212  *               identical values here
3213  * @destoff: Offset within @inode to start clone
3214  */
3215 static int btrfs_clone(struct inode *src, struct inode *inode,
3216                        const u64 off, const u64 olen, const u64 olen_aligned,
3217                        const u64 destoff)
3218 {
3219         struct btrfs_root *root = BTRFS_I(inode)->root;
3220         struct btrfs_path *path = NULL;
3221         struct extent_buffer *leaf;
3222         struct btrfs_trans_handle *trans;
3223         char *buf = NULL;
3224         struct btrfs_key key;
3225         u32 nritems;
3226         int slot;
3227         int ret;
3228         int no_quota;
3229         const u64 len = olen_aligned;
3230         u64 last_disko = 0;
3231         u64 last_dest_end = destoff;
3232
3233         ret = -ENOMEM;
3234         buf = vmalloc(root->nodesize);
3235         if (!buf)
3236                 return ret;
3237
3238         path = btrfs_alloc_path();
3239         if (!path) {
3240                 vfree(buf);
3241                 return ret;
3242         }
3243
3244         path->reada = 2;
3245         /* clone data */
3246         key.objectid = btrfs_ino(src);
3247         key.type = BTRFS_EXTENT_DATA_KEY;
3248         key.offset = off;
3249
3250         while (1) {
3251                 /*
3252                  * note the key will change type as we walk through the
3253                  * tree.
3254                  */
3255                 path->leave_spinning = 1;
3256                 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3257                                 0, 0);
3258                 if (ret < 0)
3259                         goto out;
3260                 /*
3261                  * First search, if no extent item that starts at offset off was
3262                  * found but the previous item is an extent item, it's possible
3263                  * it might overlap our target range, therefore process it.
3264                  */
3265                 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3266                         btrfs_item_key_to_cpu(path->nodes[0], &key,
3267                                               path->slots[0] - 1);
3268                         if (key.type == BTRFS_EXTENT_DATA_KEY)
3269                                 path->slots[0]--;
3270                 }
3271
3272                 nritems = btrfs_header_nritems(path->nodes[0]);
3273 process_slot:
3274                 no_quota = 1;
3275                 if (path->slots[0] >= nritems) {
3276                         ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3277                         if (ret < 0)
3278                                 goto out;
3279                         if (ret > 0)
3280                                 break;
3281                         nritems = btrfs_header_nritems(path->nodes[0]);
3282                 }
3283                 leaf = path->nodes[0];
3284                 slot = path->slots[0];
3285
3286                 btrfs_item_key_to_cpu(leaf, &key, slot);
3287                 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3288                     key.objectid != btrfs_ino(src))
3289                         break;
3290
3291                 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3292                         struct btrfs_file_extent_item *extent;
3293                         int type;
3294                         u32 size;
3295                         struct btrfs_key new_key;
3296                         u64 disko = 0, diskl = 0;
3297                         u64 datao = 0, datal = 0;
3298                         u8 comp;
3299                         u64 drop_start;
3300
3301                         extent = btrfs_item_ptr(leaf, slot,
3302                                                 struct btrfs_file_extent_item);
3303                         comp = btrfs_file_extent_compression(leaf, extent);
3304                         type = btrfs_file_extent_type(leaf, extent);
3305                         if (type == BTRFS_FILE_EXTENT_REG ||
3306                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3307                                 disko = btrfs_file_extent_disk_bytenr(leaf,
3308                                                                       extent);
3309                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3310                                                                  extent);
3311                                 datao = btrfs_file_extent_offset(leaf, extent);
3312                                 datal = btrfs_file_extent_num_bytes(leaf,
3313                                                                     extent);
3314                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3315                                 /* take upper bound, may be compressed */
3316                                 datal = btrfs_file_extent_ram_bytes(leaf,
3317                                                                     extent);
3318                         }
3319
3320                         /*
3321                          * The first search might have left us at an extent
3322                          * item that ends before our target range's start, can
3323                          * happen if we have holes and NO_HOLES feature enabled.
3324                          */
3325                         if (key.offset + datal <= off) {
3326                                 path->slots[0]++;
3327                                 goto process_slot;
3328                         } else if (key.offset >= off + len) {
3329                                 break;
3330                         }
3331
3332                         size = btrfs_item_size_nr(leaf, slot);
3333                         read_extent_buffer(leaf, buf,
3334                                            btrfs_item_ptr_offset(leaf, slot),
3335                                            size);
3336
3337                         btrfs_release_path(path);
3338                         path->leave_spinning = 0;
3339
3340                         memcpy(&new_key, &key, sizeof(new_key));
3341                         new_key.objectid = btrfs_ino(inode);
3342                         if (off <= key.offset)
3343                                 new_key.offset = key.offset + destoff - off;
3344                         else
3345                                 new_key.offset = destoff;
3346
3347                         /*
3348                          * Deal with a hole that doesn't have an extent item
3349                          * that represents it (NO_HOLES feature enabled).
3350                          * This hole is either in the middle of the cloning
3351                          * range or at the beginning (fully overlaps it or
3352                          * partially overlaps it).
3353                          */
3354                         if (new_key.offset != last_dest_end)
3355                                 drop_start = last_dest_end;
3356                         else
3357                                 drop_start = new_key.offset;
3358
3359                         /*
3360                          * 1 - adjusting old extent (we may have to split it)
3361                          * 1 - add new extent
3362                          * 1 - inode update
3363                          */
3364                         trans = btrfs_start_transaction(root, 3);
3365                         if (IS_ERR(trans)) {
3366                                 ret = PTR_ERR(trans);
3367                                 goto out;
3368                         }
3369
3370                         if (type == BTRFS_FILE_EXTENT_REG ||
3371                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3372                                 /*
3373                                  *    a  | --- range to clone ---|  b
3374                                  * | ------------- extent ------------- |
3375                                  */
3376
3377                                 /* subtract range b */
3378                                 if (key.offset + datal > off + len)
3379                                         datal = off + len - key.offset;
3380
3381                                 /* subtract range a */
3382                                 if (off > key.offset) {
3383                                         datao += off - key.offset;
3384                                         datal -= off - key.offset;
3385                                 }
3386
3387                                 ret = btrfs_drop_extents(trans, root, inode,
3388                                                          drop_start,
3389                                                          new_key.offset + datal,
3390                                                          1);
3391                                 if (ret) {
3392                                         if (ret != -EOPNOTSUPP)
3393                                                 btrfs_abort_transaction(trans,
3394                                                                 root, ret);
3395                                         btrfs_end_transaction(trans, root);
3396                                         goto out;
3397                                 }
3398
3399                                 ret = btrfs_insert_empty_item(trans, root, path,
3400                                                               &new_key, size);
3401                                 if (ret) {
3402                                         btrfs_abort_transaction(trans, root,
3403                                                                 ret);
3404                                         btrfs_end_transaction(trans, root);
3405                                         goto out;
3406                                 }
3407
3408                                 leaf = path->nodes[0];
3409                                 slot = path->slots[0];
3410                                 write_extent_buffer(leaf, buf,
3411                                             btrfs_item_ptr_offset(leaf, slot),
3412                                             size);
3413
3414                                 extent = btrfs_item_ptr(leaf, slot,
3415                                                 struct btrfs_file_extent_item);
3416
3417                                 /* disko == 0 means it's a hole */
3418                                 if (!disko)
3419                                         datao = 0;
3420
3421                                 btrfs_set_file_extent_offset(leaf, extent,
3422                                                              datao);
3423                                 btrfs_set_file_extent_num_bytes(leaf, extent,
3424                                                                 datal);
3425
3426                                 /*
3427                                  * We need to look up the roots that point at
3428                                  * this bytenr and see if the new root does.  If
3429                                  * it does not we need to make sure we update
3430                                  * quotas appropriately.
3431                                  */
3432                                 if (disko && root != BTRFS_I(src)->root &&
3433                                     disko != last_disko) {
3434                                         no_quota = check_ref(trans, root,
3435                                                              disko);
3436                                         if (no_quota < 0) {
3437                                                 btrfs_abort_transaction(trans,
3438                                                                         root,
3439                                                                         ret);
3440                                                 btrfs_end_transaction(trans,
3441                                                                       root);
3442                                                 ret = no_quota;
3443                                                 goto out;
3444                                         }
3445                                 }
3446
3447                                 if (disko) {
3448                                         inode_add_bytes(inode, datal);
3449                                         ret = btrfs_inc_extent_ref(trans, root,
3450                                                         disko, diskl, 0,
3451                                                         root->root_key.objectid,
3452                                                         btrfs_ino(inode),
3453                                                         new_key.offset - datao,
3454                                                         no_quota);
3455                                         if (ret) {
3456                                                 btrfs_abort_transaction(trans,
3457                                                                         root,
3458                                                                         ret);
3459                                                 btrfs_end_transaction(trans,
3460                                                                       root);
3461                                                 goto out;
3462
3463                                         }
3464                                 }
3465                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3466                                 u64 skip = 0;
3467                                 u64 trim = 0;
3468                                 u64 aligned_end = 0;
3469
3470                                 if (off > key.offset) {
3471                                         skip = off - key.offset;
3472                                         new_key.offset += skip;
3473                                 }
3474
3475                                 if (key.offset + datal > off + len)
3476                                         trim = key.offset + datal - (off + len);
3477
3478                                 if (comp && (skip || trim)) {
3479                                         ret = -EINVAL;
3480                                         btrfs_end_transaction(trans, root);
3481                                         goto out;
3482                                 }
3483                                 size -= skip + trim;
3484                                 datal -= skip + trim;
3485
3486                                 aligned_end = ALIGN(new_key.offset + datal,
3487                                                     root->sectorsize);
3488                                 ret = btrfs_drop_extents(trans, root, inode,
3489                                                          drop_start,
3490                                                          aligned_end,
3491                                                          1);
3492                                 if (ret) {
3493                                         if (ret != -EOPNOTSUPP)
3494                                                 btrfs_abort_transaction(trans,
3495                                                         root, ret);
3496                                         btrfs_end_transaction(trans, root);
3497                                         goto out;
3498                                 }
3499
3500                                 ret = btrfs_insert_empty_item(trans, root, path,
3501                                                               &new_key, size);
3502                                 if (ret) {
3503                                         btrfs_abort_transaction(trans, root,
3504                                                                 ret);
3505                                         btrfs_end_transaction(trans, root);
3506                                         goto out;
3507                                 }
3508
3509                                 if (skip) {
3510                                         u32 start =
3511                                           btrfs_file_extent_calc_inline_size(0);
3512                                         memmove(buf+start, buf+start+skip,
3513                                                 datal);
3514                                 }
3515
3516                                 leaf = path->nodes[0];
3517                                 slot = path->slots[0];
3518                                 write_extent_buffer(leaf, buf,
3519                                             btrfs_item_ptr_offset(leaf, slot),
3520                                             size);
3521                                 inode_add_bytes(inode, datal);
3522                         }
3523
3524                         /* If we have an implicit hole (NO_HOLES feature). */
3525                         if (drop_start < new_key.offset)
3526                                 clone_update_extent_map(inode, trans,
3527                                                 NULL, drop_start,
3528                                                 new_key.offset - drop_start);
3529
3530                         clone_update_extent_map(inode, trans, path, 0, 0);
3531
3532                         btrfs_mark_buffer_dirty(leaf);
3533                         btrfs_release_path(path);
3534
3535                         last_dest_end = ALIGN(new_key.offset + datal,
3536                                               root->sectorsize);
3537                         ret = clone_finish_inode_update(trans, inode,
3538                                                         last_dest_end,
3539                                                         destoff, olen);
3540                         if (ret)
3541                                 goto out;
3542                         if (new_key.offset + datal >= destoff + len)
3543                                 break;
3544                 }
3545                 btrfs_release_path(path);
3546                 key.offset++;
3547         }
3548         ret = 0;
3549
3550         if (last_dest_end < destoff + len) {
3551                 /*
3552                  * We have an implicit hole (NO_HOLES feature is enabled) that
3553                  * fully or partially overlaps our cloning range at its end.
3554                  */
3555                 btrfs_release_path(path);
3556
3557                 /*
3558                  * 1 - remove extent(s)
3559                  * 1 - inode update
3560                  */
3561                 trans = btrfs_start_transaction(root, 2);
3562                 if (IS_ERR(trans)) {
3563                         ret = PTR_ERR(trans);
3564                         goto out;
3565                 }
3566                 ret = btrfs_drop_extents(trans, root, inode,
3567                                          last_dest_end, destoff + len, 1);
3568                 if (ret) {
3569                         if (ret != -EOPNOTSUPP)
3570                                 btrfs_abort_transaction(trans, root, ret);
3571                         btrfs_end_transaction(trans, root);
3572                         goto out;
3573                 }
3574                 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3575                                         destoff + len - last_dest_end);
3576                 ret = clone_finish_inode_update(trans, inode, destoff + len,
3577                                                 destoff, olen);
3578         }
3579
3580 out:
3581         btrfs_free_path(path);
3582         vfree(buf);
3583         return ret;
3584 }
3585
3586 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3587                                        u64 off, u64 olen, u64 destoff)
3588 {
3589         struct inode *inode = file_inode(file);
3590         struct btrfs_root *root = BTRFS_I(inode)->root;
3591         struct fd src_file;
3592         struct inode *src;
3593         int ret;
3594         u64 len = olen;
3595         u64 bs = root->fs_info->sb->s_blocksize;
3596         int same_inode = 0;
3597
3598         /*
3599          * TODO:
3600          * - split compressed inline extents.  annoying: we need to
3601          *   decompress into destination's address_space (the file offset
3602          *   may change, so source mapping won't do), then recompress (or
3603          *   otherwise reinsert) a subrange.
3604          *
3605          * - split destination inode's inline extents.  The inline extents can
3606          *   be either compressed or non-compressed.
3607          */
3608
3609         /* the destination must be opened for writing */
3610         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3611                 return -EINVAL;
3612
3613         if (btrfs_root_readonly(root))
3614                 return -EROFS;
3615
3616         ret = mnt_want_write_file(file);
3617         if (ret)
3618                 return ret;
3619
3620         src_file = fdget(srcfd);
3621         if (!src_file.file) {
3622                 ret = -EBADF;
3623                 goto out_drop_write;
3624         }
3625
3626         ret = -EXDEV;
3627         if (src_file.file->f_path.mnt != file->f_path.mnt)
3628                 goto out_fput;
3629
3630         src = file_inode(src_file.file);
3631
3632         ret = -EINVAL;
3633         if (src == inode)
3634                 same_inode = 1;
3635
3636         /* the src must be open for reading */
3637         if (!(src_file.file->f_mode & FMODE_READ))
3638                 goto out_fput;
3639
3640         /* don't make the dst file partly checksummed */
3641         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3642             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3643                 goto out_fput;
3644
3645         ret = -EISDIR;
3646         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3647                 goto out_fput;
3648
3649         ret = -EXDEV;
3650         if (src->i_sb != inode->i_sb)
3651                 goto out_fput;
3652
3653         if (!same_inode) {
3654                 if (inode < src) {
3655                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3656                         mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3657                 } else {
3658                         mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3659                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3660                 }
3661         } else {
3662                 mutex_lock(&src->i_mutex);
3663         }
3664
3665         /* determine range to clone */
3666         ret = -EINVAL;
3667         if (off + len > src->i_size || off + len < off)
3668                 goto out_unlock;
3669         if (len == 0)
3670                 olen = len = src->i_size - off;
3671         /* if we extend to eof, continue to block boundary */
3672         if (off + len == src->i_size)
3673                 len = ALIGN(src->i_size, bs) - off;
3674
3675         /* verify the end result is block aligned */
3676         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3677             !IS_ALIGNED(destoff, bs))
3678                 goto out_unlock;
3679
3680         /* verify if ranges are overlapped within the same file */
3681         if (same_inode) {
3682                 if (destoff + len > off && destoff < off + len)
3683                         goto out_unlock;
3684         }
3685
3686         if (destoff > inode->i_size) {
3687                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3688                 if (ret)
3689                         goto out_unlock;
3690         }
3691
3692         /*
3693          * Lock the target range too. Right after we replace the file extent
3694          * items in the fs tree (which now point to the cloned data), we might
3695          * have a worker replace them with extent items relative to a write
3696          * operation that was issued before this clone operation (i.e. confront
3697          * with inode.c:btrfs_finish_ordered_io).
3698          */
3699         if (same_inode) {
3700                 u64 lock_start = min_t(u64, off, destoff);
3701                 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3702
3703                 lock_extent_range(src, lock_start, lock_len);
3704         } else {
3705                 lock_extent_range(src, off, len);
3706                 lock_extent_range(inode, destoff, len);
3707         }
3708
3709         ret = btrfs_clone(src, inode, off, olen, len, destoff);
3710
3711         if (same_inode) {
3712                 u64 lock_start = min_t(u64, off, destoff);
3713                 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3714
3715                 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3716         } else {
3717                 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3718                 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3719                               destoff + len - 1);
3720         }
3721         /*
3722          * Truncate page cache pages so that future reads will see the cloned
3723          * data immediately and not the previous data.
3724          */
3725         truncate_inode_pages_range(&inode->i_data, destoff,
3726                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
3727 out_unlock:
3728         if (!same_inode) {
3729                 if (inode < src) {
3730                         mutex_unlock(&src->i_mutex);
3731                         mutex_unlock(&inode->i_mutex);
3732                 } else {
3733                         mutex_unlock(&inode->i_mutex);
3734                         mutex_unlock(&src->i_mutex);
3735                 }
3736         } else {
3737                 mutex_unlock(&src->i_mutex);
3738         }
3739 out_fput:
3740         fdput(src_file);
3741 out_drop_write:
3742         mnt_drop_write_file(file);
3743         return ret;
3744 }
3745
3746 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3747 {
3748         struct btrfs_ioctl_clone_range_args args;
3749
3750         if (copy_from_user(&args, argp, sizeof(args)))
3751                 return -EFAULT;
3752         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3753                                  args.src_length, args.dest_offset);
3754 }
3755
3756 /*
3757  * there are many ways the trans_start and trans_end ioctls can lead
3758  * to deadlocks.  They should only be used by applications that
3759  * basically own the machine, and have a very in depth understanding
3760  * of all the possible deadlocks and enospc problems.
3761  */
3762 static long btrfs_ioctl_trans_start(struct file *file)
3763 {
3764         struct inode *inode = file_inode(file);
3765         struct btrfs_root *root = BTRFS_I(inode)->root;
3766         struct btrfs_trans_handle *trans;
3767         int ret;
3768
3769         ret = -EPERM;
3770         if (!capable(CAP_SYS_ADMIN))
3771                 goto out;
3772
3773         ret = -EINPROGRESS;
3774         if (file->private_data)
3775                 goto out;
3776
3777         ret = -EROFS;
3778         if (btrfs_root_readonly(root))
3779                 goto out;
3780
3781         ret = mnt_want_write_file(file);
3782         if (ret)
3783                 goto out;
3784
3785         atomic_inc(&root->fs_info->open_ioctl_trans);
3786
3787         ret = -ENOMEM;
3788         trans = btrfs_start_ioctl_transaction(root);
3789         if (IS_ERR(trans))
3790                 goto out_drop;
3791
3792         file->private_data = trans;
3793         return 0;
3794
3795 out_drop:
3796         atomic_dec(&root->fs_info->open_ioctl_trans);
3797         mnt_drop_write_file(file);
3798 out:
3799         return ret;
3800 }
3801
3802 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3803 {
3804         struct inode *inode = file_inode(file);
3805         struct btrfs_root *root = BTRFS_I(inode)->root;
3806         struct btrfs_root *new_root;
3807         struct btrfs_dir_item *di;
3808         struct btrfs_trans_handle *trans;
3809         struct btrfs_path *path;
3810         struct btrfs_key location;
3811         struct btrfs_disk_key disk_key;
3812         u64 objectid = 0;
3813         u64 dir_id;
3814         int ret;
3815
3816         if (!capable(CAP_SYS_ADMIN))
3817                 return -EPERM;
3818
3819         ret = mnt_want_write_file(file);
3820         if (ret)
3821                 return ret;
3822
3823         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3824                 ret = -EFAULT;
3825                 goto out;
3826         }
3827
3828         if (!objectid)
3829                 objectid = BTRFS_FS_TREE_OBJECTID;
3830
3831         location.objectid = objectid;
3832         location.type = BTRFS_ROOT_ITEM_KEY;
3833         location.offset = (u64)-1;
3834
3835         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3836         if (IS_ERR(new_root)) {
3837                 ret = PTR_ERR(new_root);
3838                 goto out;
3839         }
3840
3841         path = btrfs_alloc_path();
3842         if (!path) {
3843                 ret = -ENOMEM;
3844                 goto out;
3845         }
3846         path->leave_spinning = 1;
3847
3848         trans = btrfs_start_transaction(root, 1);
3849         if (IS_ERR(trans)) {
3850                 btrfs_free_path(path);
3851                 ret = PTR_ERR(trans);
3852                 goto out;
3853         }
3854
3855         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3856         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3857                                    dir_id, "default", 7, 1);
3858         if (IS_ERR_OR_NULL(di)) {
3859                 btrfs_free_path(path);
3860                 btrfs_end_transaction(trans, root);
3861                 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3862                            "item, this isn't going to work");
3863                 ret = -ENOENT;
3864                 goto out;
3865         }
3866
3867         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3868         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3869         btrfs_mark_buffer_dirty(path->nodes[0]);
3870         btrfs_free_path(path);
3871
3872         btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3873         btrfs_end_transaction(trans, root);
3874 out:
3875         mnt_drop_write_file(file);
3876         return ret;
3877 }
3878
3879 void btrfs_get_block_group_info(struct list_head *groups_list,
3880                                 struct btrfs_ioctl_space_info *space)
3881 {
3882         struct btrfs_block_group_cache *block_group;
3883
3884         space->total_bytes = 0;
3885         space->used_bytes = 0;
3886         space->flags = 0;
3887         list_for_each_entry(block_group, groups_list, list) {
3888                 space->flags = block_group->flags;
3889                 space->total_bytes += block_group->key.offset;
3890                 space->used_bytes +=
3891                         btrfs_block_group_used(&block_group->item);
3892         }
3893 }
3894
3895 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3896 {
3897         struct btrfs_ioctl_space_args space_args;
3898         struct btrfs_ioctl_space_info space;
3899         struct btrfs_ioctl_space_info *dest;
3900         struct btrfs_ioctl_space_info *dest_orig;
3901         struct btrfs_ioctl_space_info __user *user_dest;
3902         struct btrfs_space_info *info;
3903         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3904                        BTRFS_BLOCK_GROUP_SYSTEM,
3905                        BTRFS_BLOCK_GROUP_METADATA,
3906                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3907         int num_types = 4;
3908         int alloc_size;
3909         int ret = 0;
3910         u64 slot_count = 0;
3911         int i, c;
3912
3913         if (copy_from_user(&space_args,
3914                            (struct btrfs_ioctl_space_args __user *)arg,
3915                            sizeof(space_args)))
3916                 return -EFAULT;
3917
3918         for (i = 0; i < num_types; i++) {
3919                 struct btrfs_space_info *tmp;
3920
3921                 info = NULL;
3922                 rcu_read_lock();
3923                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3924                                         list) {
3925                         if (tmp->flags == types[i]) {
3926                                 info = tmp;
3927                                 break;
3928                         }
3929                 }
3930                 rcu_read_unlock();
3931
3932                 if (!info)
3933                         continue;
3934
3935                 down_read(&info->groups_sem);
3936                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3937                         if (!list_empty(&info->block_groups[c]))
3938                                 slot_count++;
3939                 }
3940                 up_read(&info->groups_sem);
3941         }
3942
3943         /*
3944          * Global block reserve, exported as a space_info
3945          */
3946         slot_count++;
3947
3948         /* space_slots == 0 means they are asking for a count */
3949         if (space_args.space_slots == 0) {
3950                 space_args.total_spaces = slot_count;
3951                 goto out;
3952         }
3953
3954         slot_count = min_t(u64, space_args.space_slots, slot_count);
3955
3956         alloc_size = sizeof(*dest) * slot_count;
3957
3958         /* we generally have at most 6 or so space infos, one for each raid
3959          * level.  So, a whole page should be more than enough for everyone
3960          */
3961         if (alloc_size > PAGE_CACHE_SIZE)
3962                 return -ENOMEM;
3963
3964         space_args.total_spaces = 0;
3965         dest = kmalloc(alloc_size, GFP_NOFS);
3966         if (!dest)
3967                 return -ENOMEM;
3968         dest_orig = dest;
3969
3970         /* now we have a buffer to copy into */
3971         for (i = 0; i < num_types; i++) {
3972                 struct btrfs_space_info *tmp;
3973
3974                 if (!slot_count)
3975                         break;
3976
3977                 info = NULL;
3978                 rcu_read_lock();
3979                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3980                                         list) {
3981                         if (tmp->flags == types[i]) {
3982                                 info = tmp;
3983                                 break;
3984                         }
3985                 }
3986                 rcu_read_unlock();
3987
3988                 if (!info)
3989                         continue;
3990                 down_read(&info->groups_sem);
3991                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3992                         if (!list_empty(&info->block_groups[c])) {
3993                                 btrfs_get_block_group_info(
3994                                         &info->block_groups[c], &space);
3995                                 memcpy(dest, &space, sizeof(space));
3996                                 dest++;
3997                                 space_args.total_spaces++;
3998                                 slot_count--;
3999                         }
4000                         if (!slot_count)
4001                                 break;
4002                 }
4003                 up_read(&info->groups_sem);
4004         }
4005
4006         /*
4007          * Add global block reserve
4008          */
4009         if (slot_count) {
4010                 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
4011
4012                 spin_lock(&block_rsv->lock);
4013                 space.total_bytes = block_rsv->size;
4014                 space.used_bytes = block_rsv->size - block_rsv->reserved;
4015                 spin_unlock(&block_rsv->lock);
4016                 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
4017                 memcpy(dest, &space, sizeof(space));
4018                 space_args.total_spaces++;
4019         }
4020
4021         user_dest = (struct btrfs_ioctl_space_info __user *)
4022                 (arg + sizeof(struct btrfs_ioctl_space_args));
4023
4024         if (copy_to_user(user_dest, dest_orig, alloc_size))
4025                 ret = -EFAULT;
4026
4027         kfree(dest_orig);
4028 out:
4029         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4030                 ret = -EFAULT;
4031
4032         return ret;
4033 }
4034
4035 /*
4036  * there are many ways the trans_start and trans_end ioctls can lead
4037  * to deadlocks.  They should only be used by applications that
4038  * basically own the machine, and have a very in depth understanding
4039  * of all the possible deadlocks and enospc problems.
4040  */
4041 long btrfs_ioctl_trans_end(struct file *file)
4042 {
4043         struct inode *inode = file_inode(file);
4044         struct btrfs_root *root = BTRFS_I(inode)->root;
4045         struct btrfs_trans_handle *trans;
4046
4047         trans = file->private_data;
4048         if (!trans)
4049                 return -EINVAL;
4050         file->private_data = NULL;
4051
4052         btrfs_end_transaction(trans, root);
4053
4054         atomic_dec(&root->fs_info->open_ioctl_trans);
4055
4056         mnt_drop_write_file(file);
4057         return 0;
4058 }
4059
4060 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4061                                             void __user *argp)
4062 {
4063         struct btrfs_trans_handle *trans;
4064         u64 transid;
4065         int ret;
4066
4067         trans = btrfs_attach_transaction_barrier(root);
4068         if (IS_ERR(trans)) {
4069                 if (PTR_ERR(trans) != -ENOENT)
4070                         return PTR_ERR(trans);
4071
4072                 /* No running transaction, don't bother */
4073                 transid = root->fs_info->last_trans_committed;
4074                 goto out;
4075         }
4076         transid = trans->transid;
4077         ret = btrfs_commit_transaction_async(trans, root, 0);
4078         if (ret) {
4079                 btrfs_end_transaction(trans, root);
4080                 return ret;
4081         }
4082 out:
4083         if (argp)
4084                 if (copy_to_user(argp, &transid, sizeof(transid)))
4085                         return -EFAULT;
4086         return 0;
4087 }
4088
4089 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4090                                            void __user *argp)
4091 {
4092         u64 transid;
4093
4094         if (argp) {
4095                 if (copy_from_user(&transid, argp, sizeof(transid)))
4096                         return -EFAULT;
4097         } else {
4098                 transid = 0;  /* current trans */
4099         }
4100         return btrfs_wait_for_commit(root, transid);
4101 }
4102
4103 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4104 {
4105         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4106         struct btrfs_ioctl_scrub_args *sa;
4107         int ret;
4108
4109         if (!capable(CAP_SYS_ADMIN))
4110                 return -EPERM;
4111
4112         sa = memdup_user(arg, sizeof(*sa));
4113         if (IS_ERR(sa))
4114                 return PTR_ERR(sa);
4115
4116         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4117                 ret = mnt_want_write_file(file);
4118                 if (ret)
4119                         goto out;
4120         }
4121
4122         ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4123                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4124                               0);
4125
4126         if (copy_to_user(arg, sa, sizeof(*sa)))
4127                 ret = -EFAULT;
4128
4129         if (!(sa->flags & BTRFS_SCRUB_READONLY))
4130                 mnt_drop_write_file(file);
4131 out:
4132         kfree(sa);
4133         return ret;
4134 }
4135
4136 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4137 {
4138         if (!capable(CAP_SYS_ADMIN))
4139                 return -EPERM;
4140
4141         return btrfs_scrub_cancel(root->fs_info);
4142 }
4143
4144 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4145                                        void __user *arg)
4146 {
4147         struct btrfs_ioctl_scrub_args *sa;
4148         int ret;
4149
4150         if (!capable(CAP_SYS_ADMIN))
4151                 return -EPERM;
4152
4153         sa = memdup_user(arg, sizeof(*sa));
4154         if (IS_ERR(sa))
4155                 return PTR_ERR(sa);
4156
4157         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4158
4159         if (copy_to_user(arg, sa, sizeof(*sa)))
4160                 ret = -EFAULT;
4161
4162         kfree(sa);
4163         return ret;
4164 }
4165
4166 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4167                                       void __user *arg)
4168 {
4169         struct btrfs_ioctl_get_dev_stats *sa;
4170         int ret;
4171
4172         sa = memdup_user(arg, sizeof(*sa));
4173         if (IS_ERR(sa))
4174                 return PTR_ERR(sa);
4175
4176         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4177                 kfree(sa);
4178                 return -EPERM;
4179         }
4180
4181         ret = btrfs_get_dev_stats(root, sa);
4182
4183         if (copy_to_user(arg, sa, sizeof(*sa)))
4184                 ret = -EFAULT;
4185
4186         kfree(sa);
4187         return ret;
4188 }
4189
4190 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4191 {
4192         struct btrfs_ioctl_dev_replace_args *p;
4193         int ret;
4194
4195         if (!capable(CAP_SYS_ADMIN))
4196                 return -EPERM;
4197
4198         p = memdup_user(arg, sizeof(*p));
4199         if (IS_ERR(p))
4200                 return PTR_ERR(p);
4201
4202         switch (p->cmd) {
4203         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4204                 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4205                         ret = -EROFS;
4206                         goto out;
4207                 }
4208                 if (atomic_xchg(
4209                         &root->fs_info->mutually_exclusive_operation_running,
4210                         1)) {
4211                         ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4212                 } else {
4213                         ret = btrfs_dev_replace_start(root, p);
4214                         atomic_set(
4215                          &root->fs_info->mutually_exclusive_operation_running,
4216                          0);
4217                 }
4218                 break;
4219         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4220                 btrfs_dev_replace_status(root->fs_info, p);
4221                 ret = 0;
4222                 break;
4223         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4224                 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4225                 break;
4226         default:
4227                 ret = -EINVAL;
4228                 break;
4229         }
4230
4231         if (copy_to_user(arg, p, sizeof(*p)))
4232                 ret = -EFAULT;
4233 out:
4234         kfree(p);
4235         return ret;
4236 }
4237
4238 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4239 {
4240         int ret = 0;
4241         int i;
4242         u64 rel_ptr;
4243         int size;
4244         struct btrfs_ioctl_ino_path_args *ipa = NULL;
4245         struct inode_fs_paths *ipath = NULL;
4246         struct btrfs_path *path;
4247
4248         if (!capable(CAP_DAC_READ_SEARCH))
4249                 return -EPERM;
4250
4251         path = btrfs_alloc_path();
4252         if (!path) {
4253                 ret = -ENOMEM;
4254                 goto out;
4255         }
4256
4257         ipa = memdup_user(arg, sizeof(*ipa));
4258         if (IS_ERR(ipa)) {
4259                 ret = PTR_ERR(ipa);
4260                 ipa = NULL;
4261                 goto out;
4262         }
4263
4264         size = min_t(u32, ipa->size, 4096);
4265         ipath = init_ipath(size, root, path);
4266         if (IS_ERR(ipath)) {
4267                 ret = PTR_ERR(ipath);
4268                 ipath = NULL;
4269                 goto out;
4270         }
4271
4272         ret = paths_from_inode(ipa->inum, ipath);
4273         if (ret < 0)
4274                 goto out;
4275
4276         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4277                 rel_ptr = ipath->fspath->val[i] -
4278                           (u64)(unsigned long)ipath->fspath->val;
4279                 ipath->fspath->val[i] = rel_ptr;
4280         }
4281
4282         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4283                            (void *)(unsigned long)ipath->fspath, size);
4284         if (ret) {
4285                 ret = -EFAULT;
4286                 goto out;
4287         }
4288
4289 out:
4290         btrfs_free_path(path);
4291         free_ipath(ipath);
4292         kfree(ipa);
4293
4294         return ret;
4295 }
4296
4297 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4298 {
4299         struct btrfs_data_container *inodes = ctx;
4300         const size_t c = 3 * sizeof(u64);
4301
4302         if (inodes->bytes_left >= c) {
4303                 inodes->bytes_left -= c;
4304                 inodes->val[inodes->elem_cnt] = inum;
4305                 inodes->val[inodes->elem_cnt + 1] = offset;
4306                 inodes->val[inodes->elem_cnt + 2] = root;
4307                 inodes->elem_cnt += 3;
4308         } else {
4309                 inodes->bytes_missing += c - inodes->bytes_left;
4310                 inodes->bytes_left = 0;
4311                 inodes->elem_missed += 3;
4312         }
4313
4314         return 0;
4315 }
4316
4317 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4318                                         void __user *arg)
4319 {
4320         int ret = 0;
4321         int size;
4322         struct btrfs_ioctl_logical_ino_args *loi;
4323         struct btrfs_data_container *inodes = NULL;
4324         struct btrfs_path *path = NULL;
4325
4326         if (!capable(CAP_SYS_ADMIN))
4327                 return -EPERM;
4328
4329         loi = memdup_user(arg, sizeof(*loi));
4330         if (IS_ERR(loi)) {
4331                 ret = PTR_ERR(loi);
4332                 loi = NULL;
4333                 goto out;
4334         }
4335
4336         path = btrfs_alloc_path();
4337         if (!path) {
4338                 ret = -ENOMEM;
4339                 goto out;
4340         }
4341
4342         size = min_t(u32, loi->size, 64 * 1024);
4343         inodes = init_data_container(size);
4344         if (IS_ERR(inodes)) {
4345                 ret = PTR_ERR(inodes);
4346                 inodes = NULL;
4347                 goto out;
4348         }
4349
4350         ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4351                                           build_ino_list, inodes);
4352         if (ret == -EINVAL)
4353                 ret = -ENOENT;
4354         if (ret < 0)
4355                 goto out;
4356
4357         ret = copy_to_user((void *)(unsigned long)loi->inodes,
4358                            (void *)(unsigned long)inodes, size);
4359         if (ret)
4360                 ret = -EFAULT;
4361
4362 out:
4363         btrfs_free_path(path);
4364         vfree(inodes);
4365         kfree(loi);
4366
4367         return ret;
4368 }
4369
4370 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4371                                struct btrfs_ioctl_balance_args *bargs)
4372 {
4373         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4374
4375         bargs->flags = bctl->flags;
4376
4377         if (atomic_read(&fs_info->balance_running))
4378                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4379         if (atomic_read(&fs_info->balance_pause_req))
4380                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4381         if (atomic_read(&fs_info->balance_cancel_req))
4382                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4383
4384         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4385         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4386         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4387
4388         if (lock) {
4389                 spin_lock(&fs_info->balance_lock);
4390                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4391                 spin_unlock(&fs_info->balance_lock);
4392         } else {
4393                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4394         }
4395 }
4396
4397 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4398 {
4399         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4400         struct btrfs_fs_info *fs_info = root->fs_info;
4401         struct btrfs_ioctl_balance_args *bargs;
4402         struct btrfs_balance_control *bctl;
4403         bool need_unlock; /* for mut. excl. ops lock */
4404         int ret;
4405
4406         if (!capable(CAP_SYS_ADMIN))
4407                 return -EPERM;
4408
4409         ret = mnt_want_write_file(file);
4410         if (ret)
4411                 return ret;
4412
4413 again:
4414         if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4415                 mutex_lock(&fs_info->volume_mutex);
4416                 mutex_lock(&fs_info->balance_mutex);
4417                 need_unlock = true;
4418                 goto locked;
4419         }
4420
4421         /*
4422          * mut. excl. ops lock is locked.  Three possibilites:
4423          *   (1) some other op is running
4424          *   (2) balance is running
4425          *   (3) balance is paused -- special case (think resume)
4426          */
4427         mutex_lock(&fs_info->balance_mutex);
4428         if (fs_info->balance_ctl) {
4429                 /* this is either (2) or (3) */
4430                 if (!atomic_read(&fs_info->balance_running)) {
4431                         mutex_unlock(&fs_info->balance_mutex);
4432                         if (!mutex_trylock(&fs_info->volume_mutex))
4433                                 goto again;
4434                         mutex_lock(&fs_info->balance_mutex);
4435
4436                         if (fs_info->balance_ctl &&
4437                             !atomic_read(&fs_info->balance_running)) {
4438                                 /* this is (3) */
4439                                 need_unlock = false;
4440                                 goto locked;
4441                         }
4442
4443                         mutex_unlock(&fs_info->balance_mutex);
4444                         mutex_unlock(&fs_info->volume_mutex);
4445                         goto again;
4446                 } else {
4447                         /* this is (2) */
4448                         mutex_unlock(&fs_info->balance_mutex);
4449                         ret = -EINPROGRESS;
4450                         goto out;
4451                 }
4452         } else {
4453                 /* this is (1) */
4454                 mutex_unlock(&fs_info->balance_mutex);
4455                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4456                 goto out;
4457         }
4458
4459 locked:
4460         BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4461
4462         if (arg) {
4463                 bargs = memdup_user(arg, sizeof(*bargs));
4464                 if (IS_ERR(bargs)) {
4465                         ret = PTR_ERR(bargs);
4466                         goto out_unlock;
4467                 }
4468
4469                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4470                         if (!fs_info->balance_ctl) {
4471                                 ret = -ENOTCONN;
4472                                 goto out_bargs;
4473                         }
4474
4475                         bctl = fs_info->balance_ctl;
4476                         spin_lock(&fs_info->balance_lock);
4477                         bctl->flags |= BTRFS_BALANCE_RESUME;
4478                         spin_unlock(&fs_info->balance_lock);
4479
4480                         goto do_balance;
4481                 }
4482         } else {
4483                 bargs = NULL;
4484         }
4485
4486         if (fs_info->balance_ctl) {
4487                 ret = -EINPROGRESS;
4488                 goto out_bargs;
4489         }
4490
4491         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4492         if (!bctl) {
4493                 ret = -ENOMEM;
4494                 goto out_bargs;
4495         }
4496
4497         bctl->fs_info = fs_info;
4498         if (arg) {
4499                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4500                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4501                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4502
4503                 bctl->flags = bargs->flags;
4504         } else {
4505                 /* balance everything - no filters */
4506                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4507         }
4508
4509 do_balance:
4510         /*
4511          * Ownership of bctl and mutually_exclusive_operation_running
4512          * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
4513          * or, if restriper was paused all the way until unmount, in
4514          * free_fs_info.  mutually_exclusive_operation_running is
4515          * cleared in __cancel_balance.
4516          */
4517         need_unlock = false;
4518
4519         ret = btrfs_balance(bctl, bargs);
4520
4521         if (arg) {
4522                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4523                         ret = -EFAULT;
4524         }
4525
4526 out_bargs:
4527         kfree(bargs);
4528 out_unlock:
4529         mutex_unlock(&fs_info->balance_mutex);
4530         mutex_unlock(&fs_info->volume_mutex);
4531         if (need_unlock)
4532                 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4533 out:
4534         mnt_drop_write_file(file);
4535         return ret;
4536 }
4537
4538 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4539 {
4540         if (!capable(CAP_SYS_ADMIN))
4541                 return -EPERM;
4542
4543         switch (cmd) {
4544         case BTRFS_BALANCE_CTL_PAUSE:
4545                 return btrfs_pause_balance(root->fs_info);
4546         case BTRFS_BALANCE_CTL_CANCEL:
4547                 return btrfs_cancel_balance(root->fs_info);
4548         }
4549
4550         return -EINVAL;
4551 }
4552
4553 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4554                                          void __user *arg)
4555 {
4556         struct btrfs_fs_info *fs_info = root->fs_info;
4557         struct btrfs_ioctl_balance_args *bargs;
4558         int ret = 0;
4559
4560         if (!capable(CAP_SYS_ADMIN))
4561                 return -EPERM;
4562
4563         mutex_lock(&fs_info->balance_mutex);
4564         if (!fs_info->balance_ctl) {
4565                 ret = -ENOTCONN;
4566                 goto out;
4567         }
4568
4569         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4570         if (!bargs) {
4571                 ret = -ENOMEM;
4572                 goto out;
4573         }
4574
4575         update_ioctl_balance_args(fs_info, 1, bargs);
4576
4577         if (copy_to_user(arg, bargs, sizeof(*bargs)))
4578                 ret = -EFAULT;
4579
4580         kfree(bargs);
4581 out:
4582         mutex_unlock(&fs_info->balance_mutex);
4583         return ret;
4584 }
4585
4586 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4587 {
4588         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4589         struct btrfs_ioctl_quota_ctl_args *sa;
4590         struct btrfs_trans_handle *trans = NULL;
4591         int ret;
4592         int err;
4593
4594         if (!capable(CAP_SYS_ADMIN))
4595                 return -EPERM;
4596
4597         ret = mnt_want_write_file(file);
4598         if (ret)
4599                 return ret;
4600
4601         sa = memdup_user(arg, sizeof(*sa));
4602         if (IS_ERR(sa)) {
4603                 ret = PTR_ERR(sa);
4604                 goto drop_write;
4605         }
4606
4607         down_write(&root->fs_info->subvol_sem);
4608         trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4609         if (IS_ERR(trans)) {
4610                 ret = PTR_ERR(trans);
4611                 goto out;
4612         }
4613
4614         switch (sa->cmd) {
4615         case BTRFS_QUOTA_CTL_ENABLE:
4616                 ret = btrfs_quota_enable(trans, root->fs_info);
4617                 break;
4618         case BTRFS_QUOTA_CTL_DISABLE:
4619                 ret = btrfs_quota_disable(trans, root->fs_info);
4620                 break;
4621         default:
4622                 ret = -EINVAL;
4623                 break;
4624         }
4625
4626         err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4627         if (err && !ret)
4628                 ret = err;
4629 out:
4630         kfree(sa);
4631         up_write(&root->fs_info->subvol_sem);
4632 drop_write:
4633         mnt_drop_write_file(file);
4634         return ret;
4635 }
4636
4637 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4638 {
4639         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4640         struct btrfs_ioctl_qgroup_assign_args *sa;
4641         struct btrfs_trans_handle *trans;
4642         int ret;
4643         int err;
4644
4645         if (!capable(CAP_SYS_ADMIN))
4646                 return -EPERM;
4647
4648         ret = mnt_want_write_file(file);
4649         if (ret)
4650                 return ret;
4651
4652         sa = memdup_user(arg, sizeof(*sa));
4653         if (IS_ERR(sa)) {
4654                 ret = PTR_ERR(sa);
4655                 goto drop_write;
4656         }
4657
4658         trans = btrfs_join_transaction(root);
4659         if (IS_ERR(trans)) {
4660                 ret = PTR_ERR(trans);
4661                 goto out;
4662         }
4663
4664         /* FIXME: check if the IDs really exist */
4665         if (sa->assign) {
4666                 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4667                                                 sa->src, sa->dst);
4668         } else {
4669                 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4670                                                 sa->src, sa->dst);
4671         }
4672
4673         err = btrfs_end_transaction(trans, root);
4674         if (err && !ret)
4675                 ret = err;
4676
4677 out:
4678         kfree(sa);
4679 drop_write:
4680         mnt_drop_write_file(file);
4681         return ret;
4682 }
4683
4684 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4685 {
4686         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4687         struct btrfs_ioctl_qgroup_create_args *sa;
4688         struct btrfs_trans_handle *trans;
4689         int ret;
4690         int err;
4691
4692         if (!capable(CAP_SYS_ADMIN))
4693                 return -EPERM;
4694
4695         ret = mnt_want_write_file(file);
4696         if (ret)
4697                 return ret;
4698
4699         sa = memdup_user(arg, sizeof(*sa));
4700         if (IS_ERR(sa)) {
4701                 ret = PTR_ERR(sa);
4702                 goto drop_write;
4703         }
4704
4705         if (!sa->qgroupid) {
4706                 ret = -EINVAL;
4707                 goto out;
4708         }
4709
4710         trans = btrfs_join_transaction(root);
4711         if (IS_ERR(trans)) {
4712                 ret = PTR_ERR(trans);
4713                 goto out;
4714         }
4715
4716         /* FIXME: check if the IDs really exist */
4717         if (sa->create) {
4718                 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
4719                                           NULL);
4720         } else {
4721                 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4722         }
4723
4724         err = btrfs_end_transaction(trans, root);
4725         if (err && !ret)
4726                 ret = err;
4727
4728 out:
4729         kfree(sa);
4730 drop_write:
4731         mnt_drop_write_file(file);
4732         return ret;
4733 }
4734
4735 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4736 {
4737         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4738         struct btrfs_ioctl_qgroup_limit_args *sa;
4739         struct btrfs_trans_handle *trans;
4740         int ret;
4741         int err;
4742         u64 qgroupid;
4743
4744         if (!capable(CAP_SYS_ADMIN))
4745                 return -EPERM;
4746
4747         ret = mnt_want_write_file(file);
4748         if (ret)
4749                 return ret;
4750
4751         sa = memdup_user(arg, sizeof(*sa));
4752         if (IS_ERR(sa)) {
4753                 ret = PTR_ERR(sa);
4754                 goto drop_write;
4755         }
4756
4757         trans = btrfs_join_transaction(root);
4758         if (IS_ERR(trans)) {
4759                 ret = PTR_ERR(trans);
4760                 goto out;
4761         }
4762
4763         qgroupid = sa->qgroupid;
4764         if (!qgroupid) {
4765                 /* take the current subvol as qgroup */
4766                 qgroupid = root->root_key.objectid;
4767         }
4768
4769         /* FIXME: check if the IDs really exist */
4770         ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4771
4772         err = btrfs_end_transaction(trans, root);
4773         if (err && !ret)
4774                 ret = err;
4775
4776 out:
4777         kfree(sa);
4778 drop_write:
4779         mnt_drop_write_file(file);
4780         return ret;
4781 }
4782
4783 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4784 {
4785         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4786         struct btrfs_ioctl_quota_rescan_args *qsa;
4787         int ret;
4788
4789         if (!capable(CAP_SYS_ADMIN))
4790                 return -EPERM;
4791
4792         ret = mnt_want_write_file(file);
4793         if (ret)
4794                 return ret;
4795
4796         qsa = memdup_user(arg, sizeof(*qsa));
4797         if (IS_ERR(qsa)) {
4798                 ret = PTR_ERR(qsa);
4799                 goto drop_write;
4800         }
4801
4802         if (qsa->flags) {
4803                 ret = -EINVAL;
4804                 goto out;
4805         }
4806
4807         ret = btrfs_qgroup_rescan(root->fs_info);
4808
4809 out:
4810         kfree(qsa);
4811 drop_write:
4812         mnt_drop_write_file(file);
4813         return ret;
4814 }
4815
4816 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4817 {
4818         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4819         struct btrfs_ioctl_quota_rescan_args *qsa;
4820         int ret = 0;
4821
4822         if (!capable(CAP_SYS_ADMIN))
4823                 return -EPERM;
4824
4825         qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4826         if (!qsa)
4827                 return -ENOMEM;
4828
4829         if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4830                 qsa->flags = 1;
4831                 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4832         }
4833
4834         if (copy_to_user(arg, qsa, sizeof(*qsa)))
4835                 ret = -EFAULT;
4836
4837         kfree(qsa);
4838         return ret;
4839 }
4840
4841 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4842 {
4843         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4844
4845         if (!capable(CAP_SYS_ADMIN))
4846                 return -EPERM;
4847
4848         return btrfs_qgroup_wait_for_completion(root->fs_info);
4849 }
4850
4851 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4852                                             struct btrfs_ioctl_received_subvol_args *sa)
4853 {
4854         struct inode *inode = file_inode(file);
4855         struct btrfs_root *root = BTRFS_I(inode)->root;
4856         struct btrfs_root_item *root_item = &root->root_item;
4857         struct btrfs_trans_handle *trans;
4858         struct timespec ct = CURRENT_TIME;
4859         int ret = 0;
4860         int received_uuid_changed;
4861
4862         if (!inode_owner_or_capable(inode))
4863                 return -EPERM;
4864
4865         ret = mnt_want_write_file(file);
4866         if (ret < 0)
4867                 return ret;
4868
4869         down_write(&root->fs_info->subvol_sem);
4870
4871         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4872                 ret = -EINVAL;
4873                 goto out;
4874         }
4875
4876         if (btrfs_root_readonly(root)) {
4877                 ret = -EROFS;
4878                 goto out;
4879         }
4880
4881         /*
4882          * 1 - root item
4883          * 2 - uuid items (received uuid + subvol uuid)
4884          */
4885         trans = btrfs_start_transaction(root, 3);
4886         if (IS_ERR(trans)) {
4887                 ret = PTR_ERR(trans);
4888                 trans = NULL;
4889                 goto out;
4890         }
4891
4892         sa->rtransid = trans->transid;
4893         sa->rtime.sec = ct.tv_sec;
4894         sa->rtime.nsec = ct.tv_nsec;
4895
4896         received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4897                                        BTRFS_UUID_SIZE);
4898         if (received_uuid_changed &&
4899             !btrfs_is_empty_uuid(root_item->received_uuid))
4900                 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4901                                     root_item->received_uuid,
4902                                     BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4903                                     root->root_key.objectid);
4904         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4905         btrfs_set_root_stransid(root_item, sa->stransid);
4906         btrfs_set_root_rtransid(root_item, sa->rtransid);
4907         btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4908         btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4909         btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4910         btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4911
4912         ret = btrfs_update_root(trans, root->fs_info->tree_root,
4913                                 &root->root_key, &root->root_item);
4914         if (ret < 0) {
4915                 btrfs_end_transaction(trans, root);
4916                 goto out;
4917         }
4918         if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4919                 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4920                                           sa->uuid,
4921                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4922                                           root->root_key.objectid);
4923                 if (ret < 0 && ret != -EEXIST) {
4924                         btrfs_abort_transaction(trans, root, ret);
4925                         goto out;
4926                 }
4927         }
4928         ret = btrfs_commit_transaction(trans, root);
4929         if (ret < 0) {
4930                 btrfs_abort_transaction(trans, root, ret);
4931                 goto out;
4932         }
4933
4934 out:
4935         up_write(&root->fs_info->subvol_sem);
4936         mnt_drop_write_file(file);
4937         return ret;
4938 }
4939
4940 #ifdef CONFIG_64BIT
4941 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4942                                                 void __user *arg)
4943 {
4944         struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4945         struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4946         int ret = 0;
4947
4948         args32 = memdup_user(arg, sizeof(*args32));
4949         if (IS_ERR(args32)) {
4950                 ret = PTR_ERR(args32);
4951                 args32 = NULL;
4952                 goto out;
4953         }
4954
4955         args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4956         if (!args64) {
4957                 ret = -ENOMEM;
4958                 goto out;
4959         }
4960
4961         memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4962         args64->stransid = args32->stransid;
4963         args64->rtransid = args32->rtransid;
4964         args64->stime.sec = args32->stime.sec;
4965         args64->stime.nsec = args32->stime.nsec;
4966         args64->rtime.sec = args32->rtime.sec;
4967         args64->rtime.nsec = args32->rtime.nsec;
4968         args64->flags = args32->flags;
4969
4970         ret = _btrfs_ioctl_set_received_subvol(file, args64);
4971         if (ret)
4972                 goto out;
4973
4974         memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4975         args32->stransid = args64->stransid;
4976         args32->rtransid = args64->rtransid;
4977         args32->stime.sec = args64->stime.sec;
4978         args32->stime.nsec = args64->stime.nsec;
4979         args32->rtime.sec = args64->rtime.sec;
4980         args32->rtime.nsec = args64->rtime.nsec;
4981         args32->flags = args64->flags;
4982
4983         ret = copy_to_user(arg, args32, sizeof(*args32));
4984         if (ret)
4985                 ret = -EFAULT;
4986
4987 out:
4988         kfree(args32);
4989         kfree(args64);
4990         return ret;
4991 }
4992 #endif
4993
4994 static long btrfs_ioctl_set_received_subvol(struct file *file,
4995                                             void __user *arg)
4996 {
4997         struct btrfs_ioctl_received_subvol_args *sa = NULL;
4998         int ret = 0;
4999
5000         sa = memdup_user(arg, sizeof(*sa));
5001         if (IS_ERR(sa)) {
5002                 ret = PTR_ERR(sa);
5003                 sa = NULL;
5004                 goto out;
5005         }
5006
5007         ret = _btrfs_ioctl_set_received_subvol(file, sa);
5008
5009         if (ret)
5010                 goto out;
5011
5012         ret = copy_to_user(arg, sa, sizeof(*sa));
5013         if (ret)
5014                 ret = -EFAULT;
5015
5016 out:
5017         kfree(sa);
5018         return ret;
5019 }
5020
5021 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
5022 {
5023         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5024         size_t len;
5025         int ret;
5026         char label[BTRFS_LABEL_SIZE];
5027
5028         spin_lock(&root->fs_info->super_lock);
5029         memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5030         spin_unlock(&root->fs_info->super_lock);
5031
5032         len = strnlen(label, BTRFS_LABEL_SIZE);
5033
5034         if (len == BTRFS_LABEL_SIZE) {
5035                 btrfs_warn(root->fs_info,
5036                         "label is too long, return the first %zu bytes", --len);
5037         }
5038
5039         ret = copy_to_user(arg, label, len);
5040
5041         return ret ? -EFAULT : 0;
5042 }
5043
5044 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5045 {
5046         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5047         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5048         struct btrfs_trans_handle *trans;
5049         char label[BTRFS_LABEL_SIZE];
5050         int ret;
5051
5052         if (!capable(CAP_SYS_ADMIN))
5053                 return -EPERM;
5054
5055         if (copy_from_user(label, arg, sizeof(label)))
5056                 return -EFAULT;
5057
5058         if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5059                 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5060                        BTRFS_LABEL_SIZE - 1);
5061                 return -EINVAL;
5062         }
5063
5064         ret = mnt_want_write_file(file);
5065         if (ret)
5066                 return ret;
5067
5068         trans = btrfs_start_transaction(root, 0);
5069         if (IS_ERR(trans)) {
5070                 ret = PTR_ERR(trans);
5071                 goto out_unlock;
5072         }
5073
5074         spin_lock(&root->fs_info->super_lock);
5075         strcpy(super_block->label, label);
5076         spin_unlock(&root->fs_info->super_lock);
5077         ret = btrfs_commit_transaction(trans, root);
5078
5079 out_unlock:
5080         mnt_drop_write_file(file);
5081         return ret;
5082 }
5083
5084 #define INIT_FEATURE_FLAGS(suffix) \
5085         { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5086           .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5087           .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5088
5089 static int btrfs_ioctl_get_supported_features(struct file *file,
5090                                               void __user *arg)
5091 {
5092         static struct btrfs_ioctl_feature_flags features[3] = {
5093                 INIT_FEATURE_FLAGS(SUPP),
5094                 INIT_FEATURE_FLAGS(SAFE_SET),
5095                 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5096         };
5097
5098         if (copy_to_user(arg, &features, sizeof(features)))
5099                 return -EFAULT;
5100
5101         return 0;
5102 }
5103
5104 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5105 {
5106         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5107         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5108         struct btrfs_ioctl_feature_flags features;
5109
5110         features.compat_flags = btrfs_super_compat_flags(super_block);
5111         features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5112         features.incompat_flags = btrfs_super_incompat_flags(super_block);
5113
5114         if (copy_to_user(arg, &features, sizeof(features)))
5115                 return -EFAULT;
5116
5117         return 0;
5118 }
5119
5120 static int check_feature_bits(struct btrfs_root *root,
5121                               enum btrfs_feature_set set,
5122                               u64 change_mask, u64 flags, u64 supported_flags,
5123                               u64 safe_set, u64 safe_clear)
5124 {
5125         const char *type = btrfs_feature_set_names[set];
5126         char *names;
5127         u64 disallowed, unsupported;
5128         u64 set_mask = flags & change_mask;
5129         u64 clear_mask = ~flags & change_mask;
5130
5131         unsupported = set_mask & ~supported_flags;
5132         if (unsupported) {
5133                 names = btrfs_printable_features(set, unsupported);
5134                 if (names) {
5135                         btrfs_warn(root->fs_info,
5136                            "this kernel does not support the %s feature bit%s",
5137                            names, strchr(names, ',') ? "s" : "");
5138                         kfree(names);
5139                 } else
5140                         btrfs_warn(root->fs_info,
5141                            "this kernel does not support %s bits 0x%llx",
5142                            type, unsupported);
5143                 return -EOPNOTSUPP;
5144         }
5145
5146         disallowed = set_mask & ~safe_set;
5147         if (disallowed) {
5148                 names = btrfs_printable_features(set, disallowed);
5149                 if (names) {
5150                         btrfs_warn(root->fs_info,
5151                            "can't set the %s feature bit%s while mounted",
5152                            names, strchr(names, ',') ? "s" : "");
5153                         kfree(names);
5154                 } else
5155                         btrfs_warn(root->fs_info,
5156                            "can't set %s bits 0x%llx while mounted",
5157                            type, disallowed);
5158                 return -EPERM;
5159         }
5160
5161         disallowed = clear_mask & ~safe_clear;
5162         if (disallowed) {
5163                 names = btrfs_printable_features(set, disallowed);
5164                 if (names) {
5165                         btrfs_warn(root->fs_info,
5166                            "can't clear the %s feature bit%s while mounted",
5167                            names, strchr(names, ',') ? "s" : "");
5168                         kfree(names);
5169                 } else
5170                         btrfs_warn(root->fs_info,
5171                            "can't clear %s bits 0x%llx while mounted",
5172                            type, disallowed);
5173                 return -EPERM;
5174         }
5175
5176         return 0;
5177 }
5178
5179 #define check_feature(root, change_mask, flags, mask_base)      \
5180 check_feature_bits(root, FEAT_##mask_base, change_mask, flags,  \
5181                    BTRFS_FEATURE_ ## mask_base ## _SUPP,        \
5182                    BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,    \
5183                    BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5184
5185 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5186 {
5187         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5188         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5189         struct btrfs_ioctl_feature_flags flags[2];
5190         struct btrfs_trans_handle *trans;
5191         u64 newflags;
5192         int ret;
5193
5194         if (!capable(CAP_SYS_ADMIN))
5195                 return -EPERM;
5196
5197         if (copy_from_user(flags, arg, sizeof(flags)))
5198                 return -EFAULT;
5199
5200         /* Nothing to do */
5201         if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5202             !flags[0].incompat_flags)
5203                 return 0;
5204
5205         ret = check_feature(root, flags[0].compat_flags,
5206                             flags[1].compat_flags, COMPAT);
5207         if (ret)
5208                 return ret;
5209
5210         ret = check_feature(root, flags[0].compat_ro_flags,
5211                             flags[1].compat_ro_flags, COMPAT_RO);
5212         if (ret)
5213                 return ret;
5214
5215         ret = check_feature(root, flags[0].incompat_flags,
5216                             flags[1].incompat_flags, INCOMPAT);
5217         if (ret)
5218                 return ret;
5219
5220         trans = btrfs_start_transaction(root, 0);
5221         if (IS_ERR(trans))
5222                 return PTR_ERR(trans);
5223
5224         spin_lock(&root->fs_info->super_lock);
5225         newflags = btrfs_super_compat_flags(super_block);
5226         newflags |= flags[0].compat_flags & flags[1].compat_flags;
5227         newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5228         btrfs_set_super_compat_flags(super_block, newflags);
5229
5230         newflags = btrfs_super_compat_ro_flags(super_block);
5231         newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5232         newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5233         btrfs_set_super_compat_ro_flags(super_block, newflags);
5234
5235         newflags = btrfs_super_incompat_flags(super_block);
5236         newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5237         newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5238         btrfs_set_super_incompat_flags(super_block, newflags);
5239         spin_unlock(&root->fs_info->super_lock);
5240
5241         return btrfs_commit_transaction(trans, root);
5242 }
5243
5244 long btrfs_ioctl(struct file *file, unsigned int
5245                 cmd, unsigned long arg)
5246 {
5247         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5248         void __user *argp = (void __user *)arg;
5249
5250         switch (cmd) {
5251         case FS_IOC_GETFLAGS:
5252                 return btrfs_ioctl_getflags(file, argp);
5253         case FS_IOC_SETFLAGS:
5254                 return btrfs_ioctl_setflags(file, argp);
5255         case FS_IOC_GETVERSION:
5256                 return btrfs_ioctl_getversion(file, argp);
5257         case FITRIM:
5258                 return btrfs_ioctl_fitrim(file, argp);
5259         case BTRFS_IOC_SNAP_CREATE:
5260                 return btrfs_ioctl_snap_create(file, argp, 0);
5261         case BTRFS_IOC_SNAP_CREATE_V2:
5262                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5263         case BTRFS_IOC_SUBVOL_CREATE:
5264                 return btrfs_ioctl_snap_create(file, argp, 1);
5265         case BTRFS_IOC_SUBVOL_CREATE_V2:
5266                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5267         case BTRFS_IOC_SNAP_DESTROY:
5268                 return btrfs_ioctl_snap_destroy(file, argp);
5269         case BTRFS_IOC_SUBVOL_GETFLAGS:
5270                 return btrfs_ioctl_subvol_getflags(file, argp);
5271         case BTRFS_IOC_SUBVOL_SETFLAGS:
5272                 return btrfs_ioctl_subvol_setflags(file, argp);
5273         case BTRFS_IOC_DEFAULT_SUBVOL:
5274                 return btrfs_ioctl_default_subvol(file, argp);
5275         case BTRFS_IOC_DEFRAG:
5276                 return btrfs_ioctl_defrag(file, NULL);
5277         case BTRFS_IOC_DEFRAG_RANGE:
5278                 return btrfs_ioctl_defrag(file, argp);
5279         case BTRFS_IOC_RESIZE:
5280                 return btrfs_ioctl_resize(file, argp);
5281         case BTRFS_IOC_ADD_DEV:
5282                 return btrfs_ioctl_add_dev(root, argp);
5283         case BTRFS_IOC_RM_DEV:
5284                 return btrfs_ioctl_rm_dev(file, argp);
5285         case BTRFS_IOC_FS_INFO:
5286                 return btrfs_ioctl_fs_info(root, argp);
5287         case BTRFS_IOC_DEV_INFO:
5288                 return btrfs_ioctl_dev_info(root, argp);
5289         case BTRFS_IOC_BALANCE:
5290                 return btrfs_ioctl_balance(file, NULL);
5291         case BTRFS_IOC_CLONE:
5292                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5293         case BTRFS_IOC_CLONE_RANGE:
5294                 return btrfs_ioctl_clone_range(file, argp);
5295         case BTRFS_IOC_TRANS_START:
5296                 return btrfs_ioctl_trans_start(file);
5297         case BTRFS_IOC_TRANS_END:
5298                 return btrfs_ioctl_trans_end(file);
5299         case BTRFS_IOC_TREE_SEARCH:
5300                 return btrfs_ioctl_tree_search(file, argp);
5301         case BTRFS_IOC_TREE_SEARCH_V2:
5302                 return btrfs_ioctl_tree_search_v2(file, argp);
5303         case BTRFS_IOC_INO_LOOKUP:
5304                 return btrfs_ioctl_ino_lookup(file, argp);
5305         case BTRFS_IOC_INO_PATHS:
5306                 return btrfs_ioctl_ino_to_path(root, argp);
5307         case BTRFS_IOC_LOGICAL_INO:
5308                 return btrfs_ioctl_logical_to_ino(root, argp);
5309         case BTRFS_IOC_SPACE_INFO:
5310                 return btrfs_ioctl_space_info(root, argp);
5311         case BTRFS_IOC_SYNC: {
5312                 int ret;
5313
5314                 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5315                 if (ret)
5316                         return ret;
5317                 ret = btrfs_sync_fs(file->f_dentry->d_sb, 1);
5318                 /*
5319                  * The transaction thread may want to do more work,
5320                  * namely it pokes the cleaner ktread that will start
5321                  * processing uncleaned subvols.
5322                  */
5323                 wake_up_process(root->fs_info->transaction_kthread);
5324                 return ret;
5325         }
5326         case BTRFS_IOC_START_SYNC:
5327                 return btrfs_ioctl_start_sync(root, argp);
5328         case BTRFS_IOC_WAIT_SYNC:
5329                 return btrfs_ioctl_wait_sync(root, argp);
5330         case BTRFS_IOC_SCRUB:
5331                 return btrfs_ioctl_scrub(file, argp);
5332         case BTRFS_IOC_SCRUB_CANCEL:
5333                 return btrfs_ioctl_scrub_cancel(root, argp);
5334         case BTRFS_IOC_SCRUB_PROGRESS:
5335                 return btrfs_ioctl_scrub_progress(root, argp);
5336         case BTRFS_IOC_BALANCE_V2:
5337                 return btrfs_ioctl_balance(file, argp);
5338         case BTRFS_IOC_BALANCE_CTL:
5339                 return btrfs_ioctl_balance_ctl(root, arg);
5340         case BTRFS_IOC_BALANCE_PROGRESS:
5341                 return btrfs_ioctl_balance_progress(root, argp);
5342         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5343                 return btrfs_ioctl_set_received_subvol(file, argp);
5344 #ifdef CONFIG_64BIT
5345         case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5346                 return btrfs_ioctl_set_received_subvol_32(file, argp);
5347 #endif
5348         case BTRFS_IOC_SEND:
5349                 return btrfs_ioctl_send(file, argp);
5350         case BTRFS_IOC_GET_DEV_STATS:
5351                 return btrfs_ioctl_get_dev_stats(root, argp);
5352         case BTRFS_IOC_QUOTA_CTL:
5353                 return btrfs_ioctl_quota_ctl(file, argp);
5354         case BTRFS_IOC_QGROUP_ASSIGN:
5355                 return btrfs_ioctl_qgroup_assign(file, argp);
5356         case BTRFS_IOC_QGROUP_CREATE:
5357                 return btrfs_ioctl_qgroup_create(file, argp);
5358         case BTRFS_IOC_QGROUP_LIMIT:
5359                 return btrfs_ioctl_qgroup_limit(file, argp);
5360         case BTRFS_IOC_QUOTA_RESCAN:
5361                 return btrfs_ioctl_quota_rescan(file, argp);
5362         case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5363                 return btrfs_ioctl_quota_rescan_status(file, argp);
5364         case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5365                 return btrfs_ioctl_quota_rescan_wait(file, argp);
5366         case BTRFS_IOC_DEV_REPLACE:
5367                 return btrfs_ioctl_dev_replace(root, argp);
5368         case BTRFS_IOC_GET_FSLABEL:
5369                 return btrfs_ioctl_get_fslabel(file, argp);
5370         case BTRFS_IOC_SET_FSLABEL:
5371                 return btrfs_ioctl_set_fslabel(file, argp);
5372         case BTRFS_IOC_FILE_EXTENT_SAME:
5373                 return btrfs_ioctl_file_extent_same(file, argp);
5374         case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5375                 return btrfs_ioctl_get_supported_features(file, argp);
5376         case BTRFS_IOC_GET_FEATURES:
5377                 return btrfs_ioctl_get_features(file, argp);
5378         case BTRFS_IOC_SET_FEATURES:
5379                 return btrfs_ioctl_set_features(file, argp);
5380         }
5381
5382         return -ENOTTY;
5383 }