fs/btrfs/ioctl.c

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #include <linux/kernel.h>
  20 #include <linux/bio.h>
  21 #include <linux/buffer_head.h>
  22 #include <linux/file.h>
  23 #include <linux/fs.h>
  24 #include <linux/fsnotify.h>
  25 #include <linux/pagemap.h>
  26 #include <linux/highmem.h>
  27 #include <linux/time.h>
  28 #include <linux/init.h>
  29 #include <linux/string.h>
  30 #include <linux/backing-dev.h>
  31 #include <linux/mount.h>
  32 #include <linux/mpage.h>
  33 #include <linux/namei.h>
  34 #include <linux/swap.h>
  35 #include <linux/writeback.h>
  36 #include <linux/statfs.h>
  37 #include <linux/compat.h>
  38 #include <linux/bit_spinlock.h>
  39 #include <linux/security.h>
  40 #include <linux/xattr.h>
  41 #include <linux/vmalloc.h>
  42 #include <linux/slab.h>
  43 #include <linux/blkdev.h>
  44 #include <linux/uuid.h>
  45 #include <linux/btrfs.h>
  46 #include <linux/uaccess.h>
  47 #include "ctree.h"
  48 #include "disk-io.h"
  49 #include "transaction.h"
  50 #include "btrfs_inode.h"
  51 #include "print-tree.h"
  52 #include "volumes.h"
  53 #include "locking.h"
  54 #include "inode-map.h"
  55 #include "backref.h"
  56 #include "rcu-string.h"
  57 #include "send.h"
  58 #include "dev-replace.h"
  59 #include "props.h"
  60 #include "sysfs.h"
  61 #include "qgroup.h"
  62
  63 #ifdef CONFIG_64BIT
  64 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
  65  * structures are incorrect, as the timespec structure from userspace
  66  * is 4 bytes too small. We define these alternatives here to teach
  67  * the kernel about the 32-bit struct packing.
  68  */
  69 struct btrfs_ioctl_timespec_32 {
  70         __u64 sec;
  71         __u32 nsec;
  72 } __attribute__ ((__packed__));
  73
  74 struct btrfs_ioctl_received_subvol_args_32 {
  75         char    uuid[BTRFS_UUID_SIZE];  /* in */
  76         __u64   stransid;               /* in */
  77         __u64   rtransid;               /* out */
  78         struct btrfs_ioctl_timespec_32 stime; /* in */
  79         struct btrfs_ioctl_timespec_32 rtime; /* out */
  80         __u64   flags;                  /* in */
  81         __u64   reserved[16];           /* in */
  82 } __attribute__ ((__packed__));
  83
  84 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
  85                                 struct btrfs_ioctl_received_subvol_args_32)
  86 #endif
  87
  88
  89 static int btrfs_clone(struct inode *src, struct inode *inode,
  90                        u64 off, u64 olen, u64 olen_aligned, u64 destoff);
  91
  92 /* Mask out flags that are inappropriate for the given type of inode. */
  93 static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
  94 {
  95         if (S_ISDIR(mode))
  96                 return flags;
  97         else if (S_ISREG(mode))
  98                 return flags & ~FS_DIRSYNC_FL;
  99         else
 100                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
 101 }
 102
 103 /*
 104  * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
 105  */
 106 static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
 107 {
 108         unsigned int iflags = 0;
 109
 110         if (flags & BTRFS_INODE_SYNC)
 111                 iflags |= FS_SYNC_FL;
 112         if (flags & BTRFS_INODE_IMMUTABLE)
 113                 iflags |= FS_IMMUTABLE_FL;
 114         if (flags & BTRFS_INODE_APPEND)
 115                 iflags |= FS_APPEND_FL;
 116         if (flags & BTRFS_INODE_NODUMP)
 117                 iflags |= FS_NODUMP_FL;
 118         if (flags & BTRFS_INODE_NOATIME)
 119                 iflags |= FS_NOATIME_FL;
 120         if (flags & BTRFS_INODE_DIRSYNC)
 121                 iflags |= FS_DIRSYNC_FL;
 122         if (flags & BTRFS_INODE_NODATACOW)
 123                 iflags |= FS_NOCOW_FL;
 124
 125         if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
 126                 iflags |= FS_COMPR_FL;
 127         else if (flags & BTRFS_INODE_NOCOMPRESS)
 128                 iflags |= FS_NOCOMP_FL;
 129
 130         return iflags;
 131 }
 132
 133 /*
 134  * Update inode->i_flags based on the btrfs internal flags.
 135  */
 136 void btrfs_update_iflags(struct inode *inode)
 137 {
 138         struct btrfs_inode *ip = BTRFS_I(inode);
 139         unsigned int new_fl = 0;
 140
 141         if (ip->flags & BTRFS_INODE_SYNC)
 142                 new_fl |= S_SYNC;
 143         if (ip->flags & BTRFS_INODE_IMMUTABLE)
 144                 new_fl |= S_IMMUTABLE;
 145         if (ip->flags & BTRFS_INODE_APPEND)
 146                 new_fl |= S_APPEND;
 147         if (ip->flags & BTRFS_INODE_NOATIME)
 148                 new_fl |= S_NOATIME;
 149         if (ip->flags & BTRFS_INODE_DIRSYNC)
 150                 new_fl |= S_DIRSYNC;
 151
 152         set_mask_bits(&inode->i_flags,
 153                       S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
 154                       new_fl);
 155 }
 156
 157 /*
 158  * Inherit flags from the parent inode.
 159  *
 160  * Currently only the compression flags and the cow flags are inherited.
 161  */
 162 void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 163 {
 164         unsigned int flags;
 165
 166         if (!dir)
 167                 return;
 168
 169         flags = BTRFS_I(dir)->flags;
 170
 171         if (flags & BTRFS_INODE_NOCOMPRESS) {
 172                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 173                 BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 174         } else if (flags & BTRFS_INODE_COMPRESS) {
 175                 BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 176                 BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 177         }
 178
 179         if (flags & BTRFS_INODE_NODATACOW) {
 180                 BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 181                 if (S_ISREG(inode->i_mode))
 182                         BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
 183         }
 184
 185         btrfs_update_iflags(inode);
 186 }
 187
 188 static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 189 {
 190         struct btrfs_inode *ip = BTRFS_I(file_inode(file));
 191         unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 192
 193         if (copy_to_user(arg, &flags, sizeof(flags)))
 194                 return -EFAULT;
 195         return 0;
 196 }
 197
 198 static int check_flags(unsigned int flags)
 199 {
 200         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 201                       FS_NOATIME_FL | FS_NODUMP_FL | \
 202                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 203                       FS_NOCOMP_FL | FS_COMPR_FL |
 204                       FS_NOCOW_FL))
 205                 return -EOPNOTSUPP;
 206
 207         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 208                 return -EINVAL;
 209
 210         return 0;
 211 }
 212
 213 static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 214 {
 215         struct inode *inode = file_inode(file);
 216         struct btrfs_inode *ip = BTRFS_I(inode);
 217         struct btrfs_root *root = ip->root;
 218         struct btrfs_trans_handle *trans;
 219         unsigned int flags, oldflags;
 220         int ret;
 221         u64 ip_oldflags;
 222         unsigned int i_oldflags;
 223         umode_t mode;
 224
 225         if (!inode_owner_or_capable(inode))
 226                 return -EPERM;
 227
 228         if (btrfs_root_readonly(root))
 229                 return -EROFS;
 230
 231         if (copy_from_user(&flags, arg, sizeof(flags)))
 232                 return -EFAULT;
 233
 234         ret = check_flags(flags);
 235         if (ret)
 236                 return ret;
 237
 238         ret = mnt_want_write_file(file);
 239         if (ret)
 240                 return ret;
 241
 242         mutex_lock(&inode->i_mutex);
 243
 244         ip_oldflags = ip->flags;
 245         i_oldflags = inode->i_flags;
 246         mode = inode->i_mode;
 247
 248         flags = btrfs_mask_flags(inode->i_mode, flags);
 249         oldflags = btrfs_flags_to_ioctl(ip->flags);
 250         if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 251                 if (!capable(CAP_LINUX_IMMUTABLE)) {
 252                         ret = -EPERM;
 253                         goto out_unlock;
 254                 }
 255         }
 256
 257         if (flags & FS_SYNC_FL)
 258                 ip->flags |= BTRFS_INODE_SYNC;
 259         else
 260                 ip->flags &= ~BTRFS_INODE_SYNC;
 261         if (flags & FS_IMMUTABLE_FL)
 262                 ip->flags |= BTRFS_INODE_IMMUTABLE;
 263         else
 264                 ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 265         if (flags & FS_APPEND_FL)
 266                 ip->flags |= BTRFS_INODE_APPEND;
 267         else
 268                 ip->flags &= ~BTRFS_INODE_APPEND;
 269         if (flags & FS_NODUMP_FL)
 270                 ip->flags |= BTRFS_INODE_NODUMP;
 271         else
 272                 ip->flags &= ~BTRFS_INODE_NODUMP;
 273         if (flags & FS_NOATIME_FL)
 274                 ip->flags |= BTRFS_INODE_NOATIME;
 275         else
 276                 ip->flags &= ~BTRFS_INODE_NOATIME;
 277         if (flags & FS_DIRSYNC_FL)
 278                 ip->flags |= BTRFS_INODE_DIRSYNC;
 279         else
 280                 ip->flags &= ~BTRFS_INODE_DIRSYNC;
 281         if (flags & FS_NOCOW_FL) {
 282                 if (S_ISREG(mode)) {
 283                         /*
 284                          * It's safe to turn csums off here, no extents exist.
 285                          * Otherwise we want the flag to reflect the real COW
 286                          * status of the file and will not set it.
 287                          */
 288                         if (inode->i_size == 0)
 289                                 ip->flags |= BTRFS_INODE_NODATACOW
 290                                            | BTRFS_INODE_NODATASUM;
 291                 } else {
 292                         ip->flags |= BTRFS_INODE_NODATACOW;
 293                 }
 294         } else {
 295                 /*
 296                  * Revert back under same assuptions as above
 297                  */
 298                 if (S_ISREG(mode)) {
 299                         if (inode->i_size == 0)
 300                                 ip->flags &= ~(BTRFS_INODE_NODATACOW
 301                                              | BTRFS_INODE_NODATASUM);
 302                 } else {
 303                         ip->flags &= ~BTRFS_INODE_NODATACOW;
 304                 }
 305         }
 306
 307         /*
 308          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 309          * flag may be changed automatically if compression code won't make
 310          * things smaller.
 311          */
 312         if (flags & FS_NOCOMP_FL) {
 313                 ip->flags &= ~BTRFS_INODE_COMPRESS;
 314                 ip->flags |= BTRFS_INODE_NOCOMPRESS;
 315
 316                 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
 317                 if (ret && ret != -ENODATA)
 318                         goto out_drop;
 319         } else if (flags & FS_COMPR_FL) {
 320                 const char *comp;
 321
 322                 ip->flags |= BTRFS_INODE_COMPRESS;
 323                 ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 324
 325                 if (root->fs_info->compress_type == BTRFS_COMPRESS_LZO)
 326                         comp = "lzo";
 327                 else
 328                         comp = "zlib";
 329                 ret = btrfs_set_prop(inode, "btrfs.compression",
 330                                      comp, strlen(comp), 0);
 331                 if (ret)
 332                         goto out_drop;
 333
 334         } else {
 335                 ret = btrfs_set_prop(inode, "btrfs.compression", NULL, 0, 0);
 336                 if (ret && ret != -ENODATA)
 337                         goto out_drop;
 338                 ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 339         }
 340
 341         trans = btrfs_start_transaction(root, 1);
 342         if (IS_ERR(trans)) {
 343                 ret = PTR_ERR(trans);
 344                 goto out_drop;
 345         }
 346
 347         btrfs_update_iflags(inode);
 348         inode_inc_iversion(inode);
 349         inode->i_ctime = CURRENT_TIME;
 350         ret = btrfs_update_inode(trans, root, inode);
 351
 352         btrfs_end_transaction(trans, root);
 353  out_drop:
 354         if (ret) {
 355                 ip->flags = ip_oldflags;
 356                 inode->i_flags = i_oldflags;
 357         }
 358
 359  out_unlock:
 360         mutex_unlock(&inode->i_mutex);
 361         mnt_drop_write_file(file);
 362         return ret;
 363 }
 364
 365 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 366 {
 367         struct inode *inode = file_inode(file);
 368
 369         return put_user(inode->i_generation, arg);
 370 }
 371
 372 static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 373 {
 374         struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
 375         struct btrfs_device *device;
 376         struct request_queue *q;
 377         struct fstrim_range range;
 378         u64 minlen = ULLONG_MAX;
 379         u64 num_devices = 0;
 380         u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 381         int ret;
 382
 383         if (!capable(CAP_SYS_ADMIN))
 384                 return -EPERM;
 385
 386         rcu_read_lock();
 387         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 388                                 dev_list) {
 389                 if (!device->bdev)
 390                         continue;
 391                 q = bdev_get_queue(device->bdev);
 392                 if (blk_queue_discard(q)) {
 393                         num_devices++;
 394                         minlen = min((u64)q->limits.discard_granularity,
 395                                      minlen);
 396                 }
 397         }
 398         rcu_read_unlock();
 399
 400         if (!num_devices)
 401                 return -EOPNOTSUPP;
 402         if (copy_from_user(&range, arg, sizeof(range)))
 403                 return -EFAULT;
 404         if (range.start > total_bytes ||
 405             range.len < fs_info->sb->s_blocksize)
 406                 return -EINVAL;
 407
 408         range.len = min(range.len, total_bytes - range.start);
 409         range.minlen = max(range.minlen, minlen);
 410         ret = btrfs_trim_fs(fs_info->tree_root, &range);
 411         if (ret < 0)
 412                 return ret;
 413
 414         if (copy_to_user(arg, &range, sizeof(range)))
 415                 return -EFAULT;
 416
 417         return 0;
 418 }
 419
 420 int btrfs_is_empty_uuid(u8 *uuid)
 421 {
 422         int i;
 423
 424         for (i = 0; i < BTRFS_UUID_SIZE; i++) {
 425                 if (uuid[i])
 426                         return 0;
 427         }
 428         return 1;
 429 }
 430
 431 static noinline int create_subvol(struct inode *dir,
 432                                   struct dentry *dentry,
 433                                   char *name, int namelen,
 434                                   u64 *async_transid,
 435                                   struct btrfs_qgroup_inherit *inherit)
 436 {
 437         struct btrfs_trans_handle *trans;
 438         struct btrfs_key key;
 439         struct btrfs_root_item root_item;
 440         struct btrfs_inode_item *inode_item;
 441         struct extent_buffer *leaf;
 442         struct btrfs_root *root = BTRFS_I(dir)->root;
 443         struct btrfs_root *new_root;
 444         struct btrfs_block_rsv block_rsv;
 445         struct timespec cur_time = CURRENT_TIME;
 446         struct inode *inode;
 447         int ret;
 448         int err;
 449         u64 objectid;
 450         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 451         u64 index = 0;
 452         u64 qgroup_reserved;
 453         uuid_le new_uuid;
 454
 455         ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 456         if (ret)
 457                 return ret;
 458
 459         /*
 460          * Don't create subvolume whose level is not zero. Or qgroup will be
 461          * screwed up since it assume subvolme qgroup's level to be 0.
 462          */
 463         if (btrfs_qgroup_level(objectid))
 464                 return -ENOSPC;
 465
 466         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 467         /*
 468          * The same as the snapshot creation, please see the comment
 469          * of create_snapshot().
 470          */
 471         ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
 472                                                8, &qgroup_reserved, false);
 473         if (ret)
 474                 return ret;
 475
 476         trans = btrfs_start_transaction(root, 0);
 477         if (IS_ERR(trans)) {
 478                 ret = PTR_ERR(trans);
 479                 btrfs_subvolume_release_metadata(root, &block_rsv,
 480                                                  qgroup_reserved);
 481                 return ret;
 482         }
 483         trans->block_rsv = &block_rsv;
 484         trans->bytes_reserved = block_rsv.size;
 485
 486         ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
 487         if (ret)
 488                 goto fail;
 489
 490         leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
 491         if (IS_ERR(leaf)) {
 492                 ret = PTR_ERR(leaf);
 493                 goto fail;
 494         }
 495
 496         memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 497         btrfs_set_header_bytenr(leaf, leaf->start);
 498         btrfs_set_header_generation(leaf, trans->transid);
 499         btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 500         btrfs_set_header_owner(leaf, objectid);
 501
 502         write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(),
 503                             BTRFS_FSID_SIZE);
 504         write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 505                             btrfs_header_chunk_tree_uuid(leaf),
 506                             BTRFS_UUID_SIZE);
 507         btrfs_mark_buffer_dirty(leaf);
 508
 509         memset(&root_item, 0, sizeof(root_item));
 510
 511         inode_item = &root_item.inode;
 512         btrfs_set_stack_inode_generation(inode_item, 1);
 513         btrfs_set_stack_inode_size(inode_item, 3);
 514         btrfs_set_stack_inode_nlink(inode_item, 1);
 515         btrfs_set_stack_inode_nbytes(inode_item, root->nodesize);
 516         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 517
 518         btrfs_set_root_flags(&root_item, 0);
 519         btrfs_set_root_limit(&root_item, 0);
 520         btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 521
 522         btrfs_set_root_bytenr(&root_item, leaf->start);
 523         btrfs_set_root_generation(&root_item, trans->transid);
 524         btrfs_set_root_level(&root_item, 0);
 525         btrfs_set_root_refs(&root_item, 1);
 526         btrfs_set_root_used(&root_item, leaf->len);
 527         btrfs_set_root_last_snapshot(&root_item, 0);
 528
 529         btrfs_set_root_generation_v2(&root_item,
 530                         btrfs_root_generation(&root_item));
 531         uuid_le_gen(&new_uuid);
 532         memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
 533         btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
 534         btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
 535         root_item.ctime = root_item.otime;
 536         btrfs_set_root_ctransid(&root_item, trans->transid);
 537         btrfs_set_root_otransid(&root_item, trans->transid);
 538
 539         btrfs_tree_unlock(leaf);
 540         free_extent_buffer(leaf);
 541         leaf = NULL;
 542
 543         btrfs_set_root_dirid(&root_item, new_dirid);
 544
 545         key.objectid = objectid;
 546         key.offset = 0;
 547         key.type = BTRFS_ROOT_ITEM_KEY;
 548         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 549                                 &root_item);
 550         if (ret)
 551                 goto fail;
 552
 553         key.offset = (u64)-1;
 554         new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 555         if (IS_ERR(new_root)) {
 556                 btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 557                 ret = PTR_ERR(new_root);
 558                 goto fail;
 559         }
 560
 561         btrfs_record_root_in_trans(trans, new_root);
 562
 563         ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
 564         if (ret) {
 565                 /* We potentially lose an unused inode item here */
 566                 btrfs_abort_transaction(trans, root, ret);
 567                 goto fail;
 568         }
 569
 570         /*
 571          * insert the directory item
 572          */
 573         ret = btrfs_set_inode_index(dir, &index);
 574         if (ret) {
 575                 btrfs_abort_transaction(trans, root, ret);
 576                 goto fail;
 577         }
 578
 579         ret = btrfs_insert_dir_item(trans, root,
 580                                     name, namelen, dir, &key,
 581                                     BTRFS_FT_DIR, index);
 582         if (ret) {
 583                 btrfs_abort_transaction(trans, root, ret);
 584                 goto fail;
 585         }
 586
 587         btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 588         ret = btrfs_update_inode(trans, root, dir);
 589         BUG_ON(ret);
 590
 591         ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 592                                  objectid, root->root_key.objectid,
 593                                  btrfs_ino(dir), index, name, namelen);
 594         BUG_ON(ret);
 595
 596         ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
 597                                   root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
 598                                   objectid);
 599         if (ret)
 600                 btrfs_abort_transaction(trans, root, ret);
 601
 602 fail:
 603         trans->block_rsv = NULL;
 604         trans->bytes_reserved = 0;
 605         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
 606
 607         if (async_transid) {
 608                 *async_transid = trans->transid;
 609                 err = btrfs_commit_transaction_async(trans, root, 1);
 610                 if (err)
 611                         err = btrfs_commit_transaction(trans, root);
 612         } else {
 613                 err = btrfs_commit_transaction(trans, root);
 614         }
 615         if (err && !ret)
 616                 ret = err;
 617
 618         if (!ret) {
 619                 inode = btrfs_lookup_dentry(dir, dentry);
 620                 if (IS_ERR(inode))
 621                         return PTR_ERR(inode);
 622                 d_instantiate(dentry, inode);
 623         }
 624         return ret;
 625 }
 626
 627 static void btrfs_wait_for_no_snapshoting_writes(struct btrfs_root *root)
 628 {
 629         s64 writers;
 630         DEFINE_WAIT(wait);
 631
 632         do {
 633                 prepare_to_wait(&root->subv_writers->wait, &wait,
 634                                 TASK_UNINTERRUPTIBLE);
 635
 636                 writers = percpu_counter_sum(&root->subv_writers->counter);
 637                 if (writers)
 638                         schedule();
 639
 640                 finish_wait(&root->subv_writers->wait, &wait);
 641         } while (writers);
 642 }
 643
 644 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 645                            struct dentry *dentry, char *name, int namelen,
 646                            u64 *async_transid, bool readonly,
 647                            struct btrfs_qgroup_inherit *inherit)
 648 {
 649         struct inode *inode;
 650         struct btrfs_pending_snapshot *pending_snapshot;
 651         struct btrfs_trans_handle *trans;
 652         int ret;
 653
 654         if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
 655                 return -EINVAL;
 656
 657         atomic_inc(&root->will_be_snapshoted);
 658         smp_mb__after_atomic();
 659         btrfs_wait_for_no_snapshoting_writes(root);
 660
 661         ret = btrfs_start_delalloc_inodes(root, 0);
 662         if (ret)
 663                 goto out;
 664
 665         btrfs_wait_ordered_extents(root, -1);
 666
 667         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 668         if (!pending_snapshot) {
 669                 ret = -ENOMEM;
 670                 goto out;
 671         }
 672
 673         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 674                              BTRFS_BLOCK_RSV_TEMP);
 675         /*
 676          * 1 - parent dir inode
 677          * 2 - dir entries
 678          * 1 - root item
 679          * 2 - root ref/backref
 680          * 1 - root of snapshot
 681          * 1 - UUID item
 682          */
 683         ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 684                                         &pending_snapshot->block_rsv, 8,
 685                                         &pending_snapshot->qgroup_reserved,
 686                                         false);
 687         if (ret)
 688                 goto free;
 689
 690         pending_snapshot->dentry = dentry;
 691         pending_snapshot->root = root;
 692         pending_snapshot->readonly = readonly;
 693         pending_snapshot->dir = dir;
 694         pending_snapshot->inherit = inherit;
 695
 696         trans = btrfs_start_transaction(root, 0);
 697         if (IS_ERR(trans)) {
 698                 ret = PTR_ERR(trans);
 699                 goto fail;
 700         }
 701
 702         spin_lock(&root->fs_info->trans_lock);
 703         list_add(&pending_snapshot->list,
 704                  &trans->transaction->pending_snapshots);
 705         spin_unlock(&root->fs_info->trans_lock);
 706         if (async_transid) {
 707                 *async_transid = trans->transid;
 708                 ret = btrfs_commit_transaction_async(trans,
 709                                      root->fs_info->extent_root, 1);
 710                 if (ret)
 711                         ret = btrfs_commit_transaction(trans, root);
 712         } else {
 713                 ret = btrfs_commit_transaction(trans,
 714                                                root->fs_info->extent_root);
 715         }
 716         if (ret)
 717                 goto fail;
 718
 719         ret = pending_snapshot->error;
 720         if (ret)
 721                 goto fail;
 722
 723         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 724         if (ret)
 725                 goto fail;
 726
 727         inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
 728         if (IS_ERR(inode)) {
 729                 ret = PTR_ERR(inode);
 730                 goto fail;
 731         }
 732
 733         d_instantiate(dentry, inode);
 734         ret = 0;
 735 fail:
 736         btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
 737                                          &pending_snapshot->block_rsv,
 738                                          pending_snapshot->qgroup_reserved);
 739 free:
 740         kfree(pending_snapshot);
 741 out:
 742         if (atomic_dec_and_test(&root->will_be_snapshoted))
 743                 wake_up_atomic_t(&root->will_be_snapshoted);
 744         return ret;
 745 }
 746
 747 /*  copy of may_delete in fs/namei.c()
 748  *      Check whether we can remove a link victim from directory dir, check
 749  *  whether the type of victim is right.
 750  *  1. We can't do it if dir is read-only (done in permission())
 751  *  2. We should have write and exec permissions on dir
 752  *  3. We can't remove anything from append-only dir
 753  *  4. We can't do anything with immutable dir (done in permission())
 754  *  5. If the sticky bit on dir is set we should either
 755  *      a. be owner of dir, or
 756  *      b. be owner of victim, or
 757  *      c. have CAP_FOWNER capability
 758  *  6. If the victim is append-only or immutable we can't do antyhing with
 759  *     links pointing to it.
 760  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 761  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 762  *  9. We can't remove a root or mountpoint.
 763  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 764  *     nfs_async_unlink().
 765  */
 766
 767 static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
 768 {
 769         int error;
 770
 771         if (d_really_is_negative(victim))
 772                 return -ENOENT;
 773
 774         BUG_ON(d_inode(victim->d_parent) != dir);
 775         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 776
 777         error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 778         if (error)
 779                 return error;
 780         if (IS_APPEND(dir))
 781                 return -EPERM;
 782         if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
 783             IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
 784                 return -EPERM;
 785         if (isdir) {
 786                 if (!d_is_dir(victim))
 787                         return -ENOTDIR;
 788                 if (IS_ROOT(victim))
 789                         return -EBUSY;
 790         } else if (d_is_dir(victim))
 791                 return -EISDIR;
 792         if (IS_DEADDIR(dir))
 793                 return -ENOENT;
 794         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 795                 return -EBUSY;
 796         return 0;
 797 }
 798
 799 /* copy of may_create in fs/namei.c() */
 800 static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 801 {
 802         if (d_really_is_positive(child))
 803                 return -EEXIST;
 804         if (IS_DEADDIR(dir))
 805                 return -ENOENT;
 806         return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 807 }
 808
 809 /*
 810  * Create a new subvolume below @parent.  This is largely modeled after
 811  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 812  * inside this filesystem so it's quite a bit simpler.
 813  */
 814 static noinline int btrfs_mksubvol(struct path *parent,
 815                                    char *name, int namelen,
 816                                    struct btrfs_root *snap_src,
 817                                    u64 *async_transid, bool readonly,
 818                                    struct btrfs_qgroup_inherit *inherit)
 819 {
 820         struct inode *dir  = d_inode(parent->dentry);
 821         struct dentry *dentry;
 822         int error;
 823
 824         error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
 825         if (error == -EINTR)
 826                 return error;
 827
 828         dentry = lookup_one_len(name, parent->dentry, namelen);
 829         error = PTR_ERR(dentry);
 830         if (IS_ERR(dentry))
 831                 goto out_unlock;
 832
 833         error = -EEXIST;
 834         if (d_really_is_positive(dentry))
 835                 goto out_dput;
 836
 837         error = btrfs_may_create(dir, dentry);
 838         if (error)
 839                 goto out_dput;
 840
 841         /*
 842          * even if this name doesn't exist, we may get hash collisions.
 843          * check for them now when we can safely fail
 844          */
 845         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 846                                                dir->i_ino, name,
 847                                                namelen);
 848         if (error)
 849                 goto out_dput;
 850
 851         down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 852
 853         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 854                 goto out_up_read;
 855
 856         if (snap_src) {
 857                 error = create_snapshot(snap_src, dir, dentry, name, namelen,
 858                                         async_transid, readonly, inherit);
 859         } else {
 860                 error = create_subvol(dir, dentry, name, namelen,
 861                                       async_transid, inherit);
 862         }
 863         if (!error)
 864                 fsnotify_mkdir(dir, dentry);
 865 out_up_read:
 866         up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 867 out_dput:
 868         dput(dentry);
 869 out_unlock:
 870         mutex_unlock(&dir->i_mutex);
 871         return error;
 872 }
 873
 874 /*
 875  * When we're defragging a range, we don't want to kick it off again
 876  * if it is really just waiting for delalloc to send it down.
 877  * If we find a nice big extent or delalloc range for the bytes in the
 878  * file you want to defrag, we return 0 to let you know to skip this
 879  * part of the file
 880  */
 881 static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
 882 {
 883         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 884         struct extent_map *em = NULL;
 885         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 886         u64 end;
 887
 888         read_lock(&em_tree->lock);
 889         em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 890         read_unlock(&em_tree->lock);
 891
 892         if (em) {
 893                 end = extent_map_end(em);
 894                 free_extent_map(em);
 895                 if (end - offset > thresh)
 896                         return 0;
 897         }
 898         /* if we already have a nice delalloc here, just stop */
 899         thresh /= 2;
 900         end = count_range_bits(io_tree, &offset, offset + thresh,
 901                                thresh, EXTENT_DELALLOC, 1);
 902         if (end >= thresh)
 903                 return 0;
 904         return 1;
 905 }
 906
 907 /*
 908  * helper function to walk through a file and find extents
 909  * newer than a specific transid, and smaller than thresh.
 910  *
 911  * This is used by the defragging code to find new and small
 912  * extents
 913  */
 914 static int find_new_extents(struct btrfs_root *root,
 915                             struct inode *inode, u64 newer_than,
 916                             u64 *off, u32 thresh)
 917 {
 918         struct btrfs_path *path;
 919         struct btrfs_key min_key;
 920         struct extent_buffer *leaf;
 921         struct btrfs_file_extent_item *extent;
 922         int type;
 923         int ret;
 924         u64 ino = btrfs_ino(inode);
 925
 926         path = btrfs_alloc_path();
 927         if (!path)
 928                 return -ENOMEM;
 929
 930         min_key.objectid = ino;
 931         min_key.type = BTRFS_EXTENT_DATA_KEY;
 932         min_key.offset = *off;
 933
 934         while (1) {
 935                 ret = btrfs_search_forward(root, &min_key, path, newer_than);
 936                 if (ret != 0)
 937                         goto none;
 938 process_slot:
 939                 if (min_key.objectid != ino)
 940                         goto none;
 941                 if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 942                         goto none;
 943
 944                 leaf = path->nodes[0];
 945                 extent = btrfs_item_ptr(leaf, path->slots[0],
 946                                         struct btrfs_file_extent_item);
 947
 948                 type = btrfs_file_extent_type(leaf, extent);
 949                 if (type == BTRFS_FILE_EXTENT_REG &&
 950                     btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 951                     check_defrag_in_cache(inode, min_key.offset, thresh)) {
 952                         *off = min_key.offset;
 953                         btrfs_free_path(path);
 954                         return 0;
 955                 }
 956
 957                 path->slots[0]++;
 958                 if (path->slots[0] < btrfs_header_nritems(leaf)) {
 959                         btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
 960                         goto process_slot;
 961                 }
 962
 963                 if (min_key.offset == (u64)-1)
 964                         goto none;
 965
 966                 min_key.offset++;
 967                 btrfs_release_path(path);
 968         }
 969 none:
 970         btrfs_free_path(path);
 971         return -ENOENT;
 972 }
 973
 974 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 975 {
 976         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 977         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 978         struct extent_map *em;
 979         u64 len = PAGE_CACHE_SIZE;
 980
 981         /*
 982          * hopefully we have this extent in the tree already, try without
 983          * the full extent lock
 984          */
 985         read_lock(&em_tree->lock);
 986         em = lookup_extent_mapping(em_tree, start, len);
 987         read_unlock(&em_tree->lock);
 988
 989         if (!em) {
 990                 struct extent_state *cached = NULL;
 991                 u64 end = start + len - 1;
 992
 993                 /* get the big lock and read metadata off disk */
 994                 lock_extent_bits(io_tree, start, end, 0, &cached);
 995                 em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 996                 unlock_extent_cached(io_tree, start, end, &cached, GFP_NOFS);
 997
 998                 if (IS_ERR(em))
 999                         return NULL;
1000         }
1001
1002         return em;
1003 }
1004
1005 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1006 {
1007         struct extent_map *next;
1008         bool ret = true;
1009
1010         /* this is the last extent */
1011         if (em->start + em->len >= i_size_read(inode))
1012                 return false;
1013
1014         next = defrag_lookup_extent(inode, em->start + em->len);
1015         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1016                 ret = false;
1017         else if ((em->block_start + em->block_len == next->block_start) &&
1018                  (em->block_len > 128 * 1024 && next->block_len > 128 * 1024))
1019                 ret = false;
1020
1021         free_extent_map(next);
1022         return ret;
1023 }
1024
1025 static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1026                                u64 *last_len, u64 *skip, u64 *defrag_end,
1027                                int compress)
1028 {
1029         struct extent_map *em;
1030         int ret = 1;
1031         bool next_mergeable = true;
1032
1033         /*
1034          * make sure that once we start defragging an extent, we keep on
1035          * defragging it
1036          */
1037         if (start < *defrag_end)
1038                 return 1;
1039
1040         *skip = 0;
1041
1042         em = defrag_lookup_extent(inode, start);
1043         if (!em)
1044                 return 0;
1045
1046         /* this will cover holes, and inline extents */
1047         if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1048                 ret = 0;
1049                 goto out;
1050         }
1051
1052         next_mergeable = defrag_check_next_extent(inode, em);
1053         /*
1054          * we hit a real extent, if it is big or the next extent is not a
1055          * real extent, don't bother defragging it
1056          */
1057         if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1058             (em->len >= thresh || !next_mergeable))
1059                 ret = 0;
1060 out:
1061         /*
1062          * last_len ends up being a counter of how many bytes we've defragged.
1063          * every time we choose not to defrag an extent, we reset *last_len
1064          * so that the next tiny extent will force a defrag.
1065          *
1066          * The end result of this is that tiny extents before a single big
1067          * extent will force at least part of that big extent to be defragged.
1068          */
1069         if (ret) {
1070                 *defrag_end = extent_map_end(em);
1071         } else {
1072                 *last_len = 0;
1073                 *skip = extent_map_end(em);
1074                 *defrag_end = 0;
1075         }
1076
1077         free_extent_map(em);
1078         return ret;
1079 }
1080
1081 /*
1082  * it doesn't do much good to defrag one or two pages
1083  * at a time.  This pulls in a nice chunk of pages
1084  * to COW and defrag.
1085  *
1086  * It also makes sure the delalloc code has enough
1087  * dirty data to avoid making new small extents as part
1088  * of the defrag
1089  *
1090  * It's a good idea to start RA on this range
1091  * before calling this.
1092  */
1093 static int cluster_pages_for_defrag(struct inode *inode,
1094                                     struct page **pages,
1095                                     unsigned long start_index,
1096                                     unsigned long num_pages)
1097 {
1098         unsigned long file_end;
1099         u64 isize = i_size_read(inode);
1100         u64 page_start;
1101         u64 page_end;
1102         u64 page_cnt;
1103         int ret;
1104         int i;
1105         int i_done;
1106         struct btrfs_ordered_extent *ordered;
1107         struct extent_state *cached_state = NULL;
1108         struct extent_io_tree *tree;
1109         gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1110
1111         file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1112         if (!isize || start_index > file_end)
1113                 return 0;
1114
1115         page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1116
1117         ret = btrfs_delalloc_reserve_space(inode,
1118                                            page_cnt << PAGE_CACHE_SHIFT);
1119         if (ret)
1120                 return ret;
1121         i_done = 0;
1122         tree = &BTRFS_I(inode)->io_tree;
1123
1124         /* step one, lock all the pages */
1125         for (i = 0; i < page_cnt; i++) {
1126                 struct page *page;
1127 again:
1128                 page = find_or_create_page(inode->i_mapping,
1129                                            start_index + i, mask);
1130                 if (!page)
1131                         break;
1132
1133                 page_start = page_offset(page);
1134                 page_end = page_start + PAGE_CACHE_SIZE - 1;
1135                 while (1) {
1136                         lock_extent_bits(tree, page_start, page_end,
1137                                          0, &cached_state);
1138                         ordered = btrfs_lookup_ordered_extent(inode,
1139                                                               page_start);
1140                         unlock_extent_cached(tree, page_start, page_end,
1141                                              &cached_state, GFP_NOFS);
1142                         if (!ordered)
1143                                 break;
1144
1145                         unlock_page(page);
1146                         btrfs_start_ordered_extent(inode, ordered, 1);
1147                         btrfs_put_ordered_extent(ordered);
1148                         lock_page(page);
1149                         /*
1150                          * we unlocked the page above, so we need check if
1151                          * it was released or not.
1152                          */
1153                         if (page->mapping != inode->i_mapping) {
1154                                 unlock_page(page);
1155                                 page_cache_release(page);
1156                                 goto again;
1157                         }
1158                 }
1159
1160                 if (!PageUptodate(page)) {
1161                         btrfs_readpage(NULL, page);
1162                         lock_page(page);
1163                         if (!PageUptodate(page)) {
1164                                 unlock_page(page);
1165                                 page_cache_release(page);
1166                                 ret = -EIO;
1167                                 break;
1168                         }
1169                 }
1170
1171                 if (page->mapping != inode->i_mapping) {
1172                         unlock_page(page);
1173                         page_cache_release(page);
1174                         goto again;
1175                 }
1176
1177                 pages[i] = page;
1178                 i_done++;
1179         }
1180         if (!i_done || ret)
1181                 goto out;
1182
1183         if (!(inode->i_sb->s_flags & MS_ACTIVE))
1184                 goto out;
1185
1186         /*
1187          * so now we have a nice long stream of locked
1188          * and up to date pages, lets wait on them
1189          */
1190         for (i = 0; i < i_done; i++)
1191                 wait_on_page_writeback(pages[i]);
1192
1193         page_start = page_offset(pages[0]);
1194         page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1195
1196         lock_extent_bits(&BTRFS_I(inode)->io_tree,
1197                          page_start, page_end - 1, 0, &cached_state);
1198         clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1199                           page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1200                           EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
1201                           &cached_state, GFP_NOFS);
1202
1203         if (i_done != page_cnt) {
1204                 spin_lock(&BTRFS_I(inode)->lock);
1205                 BTRFS_I(inode)->outstanding_extents++;
1206                 spin_unlock(&BTRFS_I(inode)->lock);
1207                 btrfs_delalloc_release_space(inode,
1208                                      (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1209         }
1210
1211
1212         set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1213                           &cached_state, GFP_NOFS);
1214
1215         unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1216                              page_start, page_end - 1, &cached_state,
1217                              GFP_NOFS);
1218
1219         for (i = 0; i < i_done; i++) {
1220                 clear_page_dirty_for_io(pages[i]);
1221                 ClearPageChecked(pages[i]);
1222                 set_page_extent_mapped(pages[i]);
1223                 set_page_dirty(pages[i]);
1224                 unlock_page(pages[i]);
1225                 page_cache_release(pages[i]);
1226         }
1227         return i_done;
1228 out:
1229         for (i = 0; i < i_done; i++) {
1230                 unlock_page(pages[i]);
1231                 page_cache_release(pages[i]);
1232         }
1233         btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1234         return ret;
1235
1236 }
1237
1238 int btrfs_defrag_file(struct inode *inode, struct file *file,
1239                       struct btrfs_ioctl_defrag_range_args *range,
1240                       u64 newer_than, unsigned long max_to_defrag)
1241 {
1242         struct btrfs_root *root = BTRFS_I(inode)->root;
1243         struct file_ra_state *ra = NULL;
1244         unsigned long last_index;
1245         u64 isize = i_size_read(inode);
1246         u64 last_len = 0;
1247         u64 skip = 0;
1248         u64 defrag_end = 0;
1249         u64 newer_off = range->start;
1250         unsigned long i;
1251         unsigned long ra_index = 0;
1252         int ret;
1253         int defrag_count = 0;
1254         int compress_type = BTRFS_COMPRESS_ZLIB;
1255         u32 extent_thresh = range->extent_thresh;
1256         unsigned long max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1257         unsigned long cluster = max_cluster;
1258         u64 new_align = ~((u64)128 * 1024 - 1);
1259         struct page **pages = NULL;
1260
1261         if (isize == 0)
1262                 return 0;
1263
1264         if (range->start >= isize)
1265                 return -EINVAL;
1266
1267         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1268                 if (range->compress_type > BTRFS_COMPRESS_TYPES)
1269                         return -EINVAL;
1270                 if (range->compress_type)
1271                         compress_type = range->compress_type;
1272         }
1273
1274         if (extent_thresh == 0)
1275                 extent_thresh = 256 * 1024;
1276
1277         /*
1278          * if we were not given a file, allocate a readahead
1279          * context
1280          */
1281         if (!file) {
1282                 ra = kzalloc(sizeof(*ra), GFP_NOFS);
1283                 if (!ra)
1284                         return -ENOMEM;
1285                 file_ra_state_init(ra, inode->i_mapping);
1286         } else {
1287                 ra = &file->f_ra;
1288         }
1289
1290         pages = kmalloc_array(max_cluster, sizeof(struct page *),
1291                         GFP_NOFS);
1292         if (!pages) {
1293                 ret = -ENOMEM;
1294                 goto out_ra;
1295         }
1296
1297         /* find the last page to defrag */
1298         if (range->start + range->len > range->start) {
1299                 last_index = min_t(u64, isize - 1,
1300                          range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1301         } else {
1302                 last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1303         }
1304
1305         if (newer_than) {
1306                 ret = find_new_extents(root, inode, newer_than,
1307                                        &newer_off, 64 * 1024);
1308                 if (!ret) {
1309                         range->start = newer_off;
1310                         /*
1311                          * we always align our defrag to help keep
1312                          * the extents in the file evenly spaced
1313                          */
1314                         i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1315                 } else
1316                         goto out_ra;
1317         } else {
1318                 i = range->start >> PAGE_CACHE_SHIFT;
1319         }
1320         if (!max_to_defrag)
1321                 max_to_defrag = last_index + 1;
1322
1323         /*
1324          * make writeback starts from i, so the defrag range can be
1325          * written sequentially.
1326          */
1327         if (i < inode->i_mapping->writeback_index)
1328                 inode->i_mapping->writeback_index = i;
1329
1330         while (i <= last_index && defrag_count < max_to_defrag &&
1331                (i < DIV_ROUND_UP(i_size_read(inode), PAGE_CACHE_SIZE))) {
1332                 /*
1333                  * make sure we stop running if someone unmounts
1334                  * the FS
1335                  */
1336                 if (!(inode->i_sb->s_flags & MS_ACTIVE))
1337                         break;
1338
1339                 if (btrfs_defrag_cancelled(root->fs_info)) {
1340                         printk(KERN_DEBUG "BTRFS: defrag_file cancelled\n");
1341                         ret = -EAGAIN;
1342                         break;
1343                 }
1344
1345                 if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1346                                          extent_thresh, &last_len, &skip,
1347                                          &defrag_end, range->flags &
1348                                          BTRFS_DEFRAG_RANGE_COMPRESS)) {
1349                         unsigned long next;
1350                         /*
1351                          * the should_defrag function tells us how much to skip
1352                          * bump our counter by the suggested amount
1353                          */
1354                         next = DIV_ROUND_UP(skip, PAGE_CACHE_SIZE);
1355                         i = max(i + 1, next);
1356                         continue;
1357                 }
1358
1359                 if (!newer_than) {
1360                         cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1361                                    PAGE_CACHE_SHIFT) - i;
1362                         cluster = min(cluster, max_cluster);
1363                 } else {
1364                         cluster = max_cluster;
1365                 }
1366
1367                 if (i + cluster > ra_index) {
1368                         ra_index = max(i, ra_index);
1369                         btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1370                                        cluster);
1371                         ra_index += max_cluster;
1372                 }
1373
1374                 mutex_lock(&inode->i_mutex);
1375                 if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1376                         BTRFS_I(inode)->force_compress = compress_type;
1377                 ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1378                 if (ret < 0) {
1379                         mutex_unlock(&inode->i_mutex);
1380                         goto out_ra;
1381                 }
1382
1383                 defrag_count += ret;
1384                 balance_dirty_pages_ratelimited(inode->i_mapping);
1385                 mutex_unlock(&inode->i_mutex);
1386
1387                 if (newer_than) {
1388                         if (newer_off == (u64)-1)
1389                                 break;
1390
1391                         if (ret > 0)
1392                                 i += ret;
1393
1394                         newer_off = max(newer_off + 1,
1395                                         (u64)i << PAGE_CACHE_SHIFT);
1396
1397                         ret = find_new_extents(root, inode,
1398                                                newer_than, &newer_off,
1399                                                64 * 1024);
1400                         if (!ret) {
1401                                 range->start = newer_off;
1402                                 i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1403                         } else {
1404                                 break;
1405                         }
1406                 } else {
1407                         if (ret > 0) {
1408                                 i += ret;
1409                                 last_len += ret << PAGE_CACHE_SHIFT;
1410                         } else {
1411                                 i++;
1412                                 last_len = 0;
1413                         }
1414                 }
1415         }
1416
1417         if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1418                 filemap_flush(inode->i_mapping);
1419                 if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1420                              &BTRFS_I(inode)->runtime_flags))
1421                         filemap_flush(inode->i_mapping);
1422         }
1423
1424         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1425                 /* the filemap_flush will queue IO into the worker threads, but
1426                  * we have to make sure the IO is actually started and that
1427                  * ordered extents get created before we return
1428                  */
1429                 atomic_inc(&root->fs_info->async_submit_draining);
1430                 while (atomic_read(&root->fs_info->nr_async_submits) ||
1431                       atomic_read(&root->fs_info->async_delalloc_pages)) {
1432                         wait_event(root->fs_info->async_submit_wait,
1433                            (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1434                             atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1435                 }
1436                 atomic_dec(&root->fs_info->async_submit_draining);
1437         }
1438
1439         if (range->compress_type == BTRFS_COMPRESS_LZO) {
1440                 btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1441         }
1442
1443         ret = defrag_count;
1444
1445 out_ra:
1446         if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1447                 mutex_lock(&inode->i_mutex);
1448                 BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1449                 mutex_unlock(&inode->i_mutex);
1450         }
1451         if (!file)
1452                 kfree(ra);
1453         kfree(pages);
1454         return ret;
1455 }
1456
1457 static noinline int btrfs_ioctl_resize(struct file *file,
1458                                         void __user *arg)
1459 {
1460         u64 new_size;
1461         u64 old_size;
1462         u64 devid = 1;
1463         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
1464         struct btrfs_ioctl_vol_args *vol_args;
1465         struct btrfs_trans_handle *trans;
1466         struct btrfs_device *device = NULL;
1467         char *sizestr;
1468         char *retptr;
1469         char *devstr = NULL;
1470         int ret = 0;
1471         int mod = 0;
1472
1473         if (!capable(CAP_SYS_ADMIN))
1474                 return -EPERM;
1475
1476         ret = mnt_want_write_file(file);
1477         if (ret)
1478                 return ret;
1479
1480         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
1481                         1)) {
1482                 mnt_drop_write_file(file);
1483                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1484         }
1485
1486         mutex_lock(&root->fs_info->volume_mutex);
1487         vol_args = memdup_user(arg, sizeof(*vol_args));
1488         if (IS_ERR(vol_args)) {
1489                 ret = PTR_ERR(vol_args);
1490                 goto out;
1491         }
1492
1493         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1494
1495         sizestr = vol_args->name;
1496         devstr = strchr(sizestr, ':');
1497         if (devstr) {
1498                 sizestr = devstr + 1;
1499                 *devstr = '\0';
1500                 devstr = vol_args->name;
1501                 ret = kstrtoull(devstr, 10, &devid);
1502                 if (ret)
1503                         goto out_free;
1504                 if (!devid) {
1505                         ret = -EINVAL;
1506                         goto out_free;
1507                 }
1508                 btrfs_info(root->fs_info, "resizing devid %llu", devid);
1509         }
1510
1511         device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
1512         if (!device) {
1513                 btrfs_info(root->fs_info, "resizer unable to find device %llu",
1514                        devid);
1515                 ret = -ENODEV;
1516                 goto out_free;
1517         }
1518
1519         if (!device->writeable) {
1520                 btrfs_info(root->fs_info,
1521                            "resizer unable to apply on readonly device %llu",
1522                        devid);
1523                 ret = -EPERM;
1524                 goto out_free;
1525         }
1526
1527         if (!strcmp(sizestr, "max"))
1528                 new_size = device->bdev->bd_inode->i_size;
1529         else {
1530                 if (sizestr[0] == '-') {
1531                         mod = -1;
1532                         sizestr++;
1533                 } else if (sizestr[0] == '+') {
1534                         mod = 1;
1535                         sizestr++;
1536                 }
1537                 new_size = memparse(sizestr, &retptr);
1538                 if (*retptr != '\0' || new_size == 0) {
1539                         ret = -EINVAL;
1540                         goto out_free;
1541                 }
1542         }
1543
1544         if (device->is_tgtdev_for_dev_replace) {
1545                 ret = -EPERM;
1546                 goto out_free;
1547         }
1548
1549         old_size = btrfs_device_get_total_bytes(device);
1550
1551         if (mod < 0) {
1552                 if (new_size > old_size) {
1553                         ret = -EINVAL;
1554                         goto out_free;
1555                 }
1556                 new_size = old_size - new_size;
1557         } else if (mod > 0) {
1558                 if (new_size > ULLONG_MAX - old_size) {
1559                         ret = -ERANGE;
1560                         goto out_free;
1561                 }
1562                 new_size = old_size + new_size;
1563         }
1564
1565         if (new_size < 256 * 1024 * 1024) {
1566                 ret = -EINVAL;
1567                 goto out_free;
1568         }
1569         if (new_size > device->bdev->bd_inode->i_size) {
1570                 ret = -EFBIG;
1571                 goto out_free;
1572         }
1573
1574         new_size = div_u64(new_size, root->sectorsize);
1575         new_size *= root->sectorsize;
1576
1577         printk_in_rcu(KERN_INFO "BTRFS: new size for %s is %llu\n",
1578                       rcu_str_deref(device->name), new_size);
1579
1580         if (new_size > old_size) {
1581                 trans = btrfs_start_transaction(root, 0);
1582                 if (IS_ERR(trans)) {
1583                         ret = PTR_ERR(trans);
1584                         goto out_free;
1585                 }
1586                 ret = btrfs_grow_device(trans, device, new_size);
1587                 btrfs_commit_transaction(trans, root);
1588         } else if (new_size < old_size) {
1589                 ret = btrfs_shrink_device(device, new_size);
1590         } /* equal, nothing need to do */
1591
1592 out_free:
1593         kfree(vol_args);
1594 out:
1595         mutex_unlock(&root->fs_info->volume_mutex);
1596         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1597         mnt_drop_write_file(file);
1598         return ret;
1599 }
1600
1601 static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1602                                 char *name, unsigned long fd, int subvol,
1603                                 u64 *transid, bool readonly,
1604                                 struct btrfs_qgroup_inherit *inherit)
1605 {
1606         int namelen;
1607         int ret = 0;
1608
1609         ret = mnt_want_write_file(file);
1610         if (ret)
1611                 goto out;
1612
1613         namelen = strlen(name);
1614         if (strchr(name, '/')) {
1615                 ret = -EINVAL;
1616                 goto out_drop_write;
1617         }
1618
1619         if (name[0] == '.' &&
1620            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1621                 ret = -EEXIST;
1622                 goto out_drop_write;
1623         }
1624
1625         if (subvol) {
1626                 ret = btrfs_mksubvol(&file->f_path, name, namelen,
1627                                      NULL, transid, readonly, inherit);
1628         } else {
1629                 struct fd src = fdget(fd);
1630                 struct inode *src_inode;
1631                 if (!src.file) {
1632                         ret = -EINVAL;
1633                         goto out_drop_write;
1634                 }
1635
1636                 src_inode = file_inode(src.file);
1637                 if (src_inode->i_sb != file_inode(file)->i_sb) {
1638                         btrfs_info(BTRFS_I(src_inode)->root->fs_info,
1639                                    "Snapshot src from another FS");
1640                         ret = -EXDEV;
1641                 } else if (!inode_owner_or_capable(src_inode)) {
1642                         /*
1643                          * Subvolume creation is not restricted, but snapshots
1644                          * are limited to own subvolumes only
1645                          */
1646                         ret = -EPERM;
1647                 } else {
1648                         ret = btrfs_mksubvol(&file->f_path, name, namelen,
1649                                              BTRFS_I(src_inode)->root,
1650                                              transid, readonly, inherit);
1651                 }
1652                 fdput(src);
1653         }
1654 out_drop_write:
1655         mnt_drop_write_file(file);
1656 out:
1657         return ret;
1658 }
1659
1660 static noinline int btrfs_ioctl_snap_create(struct file *file,
1661                                             void __user *arg, int subvol)
1662 {
1663         struct btrfs_ioctl_vol_args *vol_args;
1664         int ret;
1665
1666         vol_args = memdup_user(arg, sizeof(*vol_args));
1667         if (IS_ERR(vol_args))
1668                 return PTR_ERR(vol_args);
1669         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1670
1671         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1672                                               vol_args->fd, subvol,
1673                                               NULL, false, NULL);
1674
1675         kfree(vol_args);
1676         return ret;
1677 }
1678
1679 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1680                                                void __user *arg, int subvol)
1681 {
1682         struct btrfs_ioctl_vol_args_v2 *vol_args;
1683         int ret;
1684         u64 transid = 0;
1685         u64 *ptr = NULL;
1686         bool readonly = false;
1687         struct btrfs_qgroup_inherit *inherit = NULL;
1688
1689         vol_args = memdup_user(arg, sizeof(*vol_args));
1690         if (IS_ERR(vol_args))
1691                 return PTR_ERR(vol_args);
1692         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1693
1694         if (vol_args->flags &
1695             ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
1696               BTRFS_SUBVOL_QGROUP_INHERIT)) {
1697                 ret = -EOPNOTSUPP;
1698                 goto free_args;
1699         }
1700
1701         if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1702                 ptr = &transid;
1703         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1704                 readonly = true;
1705         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1706                 if (vol_args->size > PAGE_CACHE_SIZE) {
1707                         ret = -EINVAL;
1708                         goto free_args;
1709                 }
1710                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1711                 if (IS_ERR(inherit)) {
1712                         ret = PTR_ERR(inherit);
1713                         goto free_args;
1714                 }
1715         }
1716
1717         ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1718                                               vol_args->fd, subvol, ptr,
1719                                               readonly, inherit);
1720         if (ret)
1721                 goto free_inherit;
1722
1723         if (ptr && copy_to_user(arg +
1724                                 offsetof(struct btrfs_ioctl_vol_args_v2,
1725                                         transid),
1726                                 ptr, sizeof(*ptr)))
1727                 ret = -EFAULT;
1728
1729 free_inherit:
1730         kfree(inherit);
1731 free_args:
1732         kfree(vol_args);
1733         return ret;
1734 }
1735
1736 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1737                                                 void __user *arg)
1738 {
1739         struct inode *inode = file_inode(file);
1740         struct btrfs_root *root = BTRFS_I(inode)->root;
1741         int ret = 0;
1742         u64 flags = 0;
1743
1744         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1745                 return -EINVAL;
1746
1747         down_read(&root->fs_info->subvol_sem);
1748         if (btrfs_root_readonly(root))
1749                 flags |= BTRFS_SUBVOL_RDONLY;
1750         up_read(&root->fs_info->subvol_sem);
1751
1752         if (copy_to_user(arg, &flags, sizeof(flags)))
1753                 ret = -EFAULT;
1754
1755         return ret;
1756 }
1757
1758 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1759                                               void __user *arg)
1760 {
1761         struct inode *inode = file_inode(file);
1762         struct btrfs_root *root = BTRFS_I(inode)->root;
1763         struct btrfs_trans_handle *trans;
1764         u64 root_flags;
1765         u64 flags;
1766         int ret = 0;
1767
1768         if (!inode_owner_or_capable(inode))
1769                 return -EPERM;
1770
1771         ret = mnt_want_write_file(file);
1772         if (ret)
1773                 goto out;
1774
1775         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
1776                 ret = -EINVAL;
1777                 goto out_drop_write;
1778         }
1779
1780         if (copy_from_user(&flags, arg, sizeof(flags))) {
1781                 ret = -EFAULT;
1782                 goto out_drop_write;
1783         }
1784
1785         if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
1786                 ret = -EINVAL;
1787                 goto out_drop_write;
1788         }
1789
1790         if (flags & ~BTRFS_SUBVOL_RDONLY) {
1791                 ret = -EOPNOTSUPP;
1792                 goto out_drop_write;
1793         }
1794
1795         down_write(&root->fs_info->subvol_sem);
1796
1797         /* nothing to do */
1798         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1799                 goto out_drop_sem;
1800
1801         root_flags = btrfs_root_flags(&root->root_item);
1802         if (flags & BTRFS_SUBVOL_RDONLY) {
1803                 btrfs_set_root_flags(&root->root_item,
1804                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1805         } else {
1806                 /*
1807                  * Block RO -> RW transition if this subvolume is involved in
1808                  * send
1809                  */
1810                 spin_lock(&root->root_item_lock);
1811                 if (root->send_in_progress == 0) {
1812                         btrfs_set_root_flags(&root->root_item,
1813                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1814                         spin_unlock(&root->root_item_lock);
1815                 } else {
1816                         spin_unlock(&root->root_item_lock);
1817                         btrfs_warn(root->fs_info,
1818                         "Attempt to set subvolume %llu read-write during send",
1819                                         root->root_key.objectid);
1820                         ret = -EPERM;
1821                         goto out_drop_sem;
1822                 }
1823         }
1824
1825         trans = btrfs_start_transaction(root, 1);
1826         if (IS_ERR(trans)) {
1827                 ret = PTR_ERR(trans);
1828                 goto out_reset;
1829         }
1830
1831         ret = btrfs_update_root(trans, root->fs_info->tree_root,
1832                                 &root->root_key, &root->root_item);
1833
1834         btrfs_commit_transaction(trans, root);
1835 out_reset:
1836         if (ret)
1837                 btrfs_set_root_flags(&root->root_item, root_flags);
1838 out_drop_sem:
1839         up_write(&root->fs_info->subvol_sem);
1840 out_drop_write:
1841         mnt_drop_write_file(file);
1842 out:
1843         return ret;
1844 }
1845
1846 /*
1847  * helper to check if the subvolume references other subvolumes
1848  */
1849 static noinline int may_destroy_subvol(struct btrfs_root *root)
1850 {
1851         struct btrfs_path *path;
1852         struct btrfs_dir_item *di;
1853         struct btrfs_key key;
1854         u64 dir_id;
1855         int ret;
1856
1857         path = btrfs_alloc_path();
1858         if (!path)
1859                 return -ENOMEM;
1860
1861         /* Make sure this root isn't set as the default subvol */
1862         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
1863         di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
1864                                    dir_id, "default", 7, 0);
1865         if (di && !IS_ERR(di)) {
1866                 btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
1867                 if (key.objectid == root->root_key.objectid) {
1868                         ret = -EPERM;
1869                         btrfs_err(root->fs_info, "deleting default subvolume "
1870                                   "%llu is not allowed", key.objectid);
1871                         goto out;
1872                 }
1873                 btrfs_release_path(path);
1874         }
1875
1876         key.objectid = root->root_key.objectid;
1877         key.type = BTRFS_ROOT_REF_KEY;
1878         key.offset = (u64)-1;
1879
1880         ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1881                                 &key, path, 0, 0);
1882         if (ret < 0)
1883                 goto out;
1884         BUG_ON(ret == 0);
1885
1886         ret = 0;
1887         if (path->slots[0] > 0) {
1888                 path->slots[0]--;
1889                 btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1890                 if (key.objectid == root->root_key.objectid &&
1891                     key.type == BTRFS_ROOT_REF_KEY)
1892                         ret = -ENOTEMPTY;
1893         }
1894 out:
1895         btrfs_free_path(path);
1896         return ret;
1897 }
1898
1899 static noinline int key_in_sk(struct btrfs_key *key,
1900                               struct btrfs_ioctl_search_key *sk)
1901 {
1902         struct btrfs_key test;
1903         int ret;
1904
1905         test.objectid = sk->min_objectid;
1906         test.type = sk->min_type;
1907         test.offset = sk->min_offset;
1908
1909         ret = btrfs_comp_cpu_keys(key, &test);
1910         if (ret < 0)
1911                 return 0;
1912
1913         test.objectid = sk->max_objectid;
1914         test.type = sk->max_type;
1915         test.offset = sk->max_offset;
1916
1917         ret = btrfs_comp_cpu_keys(key, &test);
1918         if (ret > 0)
1919                 return 0;
1920         return 1;
1921 }
1922
1923 static noinline int copy_to_sk(struct btrfs_root *root,
1924                                struct btrfs_path *path,
1925                                struct btrfs_key *key,
1926                                struct btrfs_ioctl_search_key *sk,
1927                                size_t *buf_size,
1928                                char __user *ubuf,
1929                                unsigned long *sk_offset,
1930                                int *num_found)
1931 {
1932         u64 found_transid;
1933         struct extent_buffer *leaf;
1934         struct btrfs_ioctl_search_header sh;
1935         unsigned long item_off;
1936         unsigned long item_len;
1937         int nritems;
1938         int i;
1939         int slot;
1940         int ret = 0;
1941
1942         leaf = path->nodes[0];
1943         slot = path->slots[0];
1944         nritems = btrfs_header_nritems(leaf);
1945
1946         if (btrfs_header_generation(leaf) > sk->max_transid) {
1947                 i = nritems;
1948                 goto advance_key;
1949         }
1950         found_transid = btrfs_header_generation(leaf);
1951
1952         for (i = slot; i < nritems; i++) {
1953                 item_off = btrfs_item_ptr_offset(leaf, i);
1954                 item_len = btrfs_item_size_nr(leaf, i);
1955
1956                 btrfs_item_key_to_cpu(leaf, key, i);
1957                 if (!key_in_sk(key, sk))
1958                         continue;
1959
1960                 if (sizeof(sh) + item_len > *buf_size) {
1961                         if (*num_found) {
1962                                 ret = 1;
1963                                 goto out;
1964                         }
1965
1966                         /*
1967                          * return one empty item back for v1, which does not
1968                          * handle -EOVERFLOW
1969                          */
1970
1971                         *buf_size = sizeof(sh) + item_len;
1972                         item_len = 0;
1973                         ret = -EOVERFLOW;
1974                 }
1975
1976                 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
1977                         ret = 1;
1978                         goto out;
1979                 }
1980
1981                 sh.objectid = key->objectid;
1982                 sh.offset = key->offset;
1983                 sh.type = key->type;
1984                 sh.len = item_len;
1985                 sh.transid = found_transid;
1986
1987                 /* copy search result header */
1988                 if (copy_to_user(ubuf + *sk_offset, &sh, sizeof(sh))) {
1989                         ret = -EFAULT;
1990                         goto out;
1991                 }
1992
1993                 *sk_offset += sizeof(sh);
1994
1995                 if (item_len) {
1996                         char __user *up = ubuf + *sk_offset;
1997                         /* copy the item */
1998                         if (read_extent_buffer_to_user(leaf, up,
1999                                                        item_off, item_len)) {
2000                                 ret = -EFAULT;
2001                                 goto out;
2002                         }
2003
2004                         *sk_offset += item_len;
2005                 }
2006                 (*num_found)++;
2007
2008                 if (ret) /* -EOVERFLOW from above */
2009                         goto out;
2010
2011                 if (*num_found >= sk->nr_items) {
2012                         ret = 1;
2013                         goto out;
2014                 }
2015         }
2016 advance_key:
2017         ret = 0;
2018         if (key->offset < (u64)-1 && key->offset < sk->max_offset)
2019                 key->offset++;
2020         else if (key->type < (u8)-1 && key->type < sk->max_type) {
2021                 key->offset = 0;
2022                 key->type++;
2023         } else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
2024                 key->offset = 0;
2025                 key->type = 0;
2026                 key->objectid++;
2027         } else
2028                 ret = 1;
2029 out:
2030         /*
2031          *  0: all items from this leaf copied, continue with next
2032          *  1: * more items can be copied, but unused buffer is too small
2033          *     * all items were found
2034          *     Either way, it will stops the loop which iterates to the next
2035          *     leaf
2036          *  -EOVERFLOW: item was to large for buffer
2037          *  -EFAULT: could not copy extent buffer back to userspace
2038          */
2039         return ret;
2040 }
2041
2042 static noinline int search_ioctl(struct inode *inode,
2043                                  struct btrfs_ioctl_search_key *sk,
2044                                  size_t *buf_size,
2045                                  char __user *ubuf)
2046 {
2047         struct btrfs_root *root;
2048         struct btrfs_key key;
2049         struct btrfs_path *path;
2050         struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
2051         int ret;
2052         int num_found = 0;
2053         unsigned long sk_offset = 0;
2054
2055         if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2056                 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2057                 return -EOVERFLOW;
2058         }
2059
2060         path = btrfs_alloc_path();
2061         if (!path)
2062                 return -ENOMEM;
2063
2064         if (sk->tree_id == 0) {
2065                 /* search the root of the inode that was passed */
2066                 root = BTRFS_I(inode)->root;
2067         } else {
2068                 key.objectid = sk->tree_id;
2069                 key.type = BTRFS_ROOT_ITEM_KEY;
2070                 key.offset = (u64)-1;
2071                 root = btrfs_read_fs_root_no_name(info, &key);
2072                 if (IS_ERR(root)) {
2073                         printk(KERN_ERR "BTRFS: could not find root %llu\n",
2074                                sk->tree_id);
2075                         btrfs_free_path(path);
2076                         return -ENOENT;
2077                 }
2078         }
2079
2080         key.objectid = sk->min_objectid;
2081         key.type = sk->min_type;
2082         key.offset = sk->min_offset;
2083
2084         while (1) {
2085                 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2086                 if (ret != 0) {
2087                         if (ret > 0)
2088                                 ret = 0;
2089                         goto err;
2090                 }
2091                 ret = copy_to_sk(root, path, &key, sk, buf_size, ubuf,
2092                                  &sk_offset, &num_found);
2093                 btrfs_release_path(path);
2094                 if (ret)
2095                         break;
2096
2097         }
2098         if (ret > 0)
2099                 ret = 0;
2100 err:
2101         sk->nr_items = num_found;
2102         btrfs_free_path(path);
2103         return ret;
2104 }
2105
2106 static noinline int btrfs_ioctl_tree_search(struct file *file,
2107                                            void __user *argp)
2108 {
2109         struct btrfs_ioctl_search_args __user *uargs;
2110         struct btrfs_ioctl_search_key sk;
2111         struct inode *inode;
2112         int ret;
2113         size_t buf_size;
2114
2115         if (!capable(CAP_SYS_ADMIN))
2116                 return -EPERM;
2117
2118         uargs = (struct btrfs_ioctl_search_args __user *)argp;
2119
2120         if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2121                 return -EFAULT;
2122
2123         buf_size = sizeof(uargs->buf);
2124
2125         inode = file_inode(file);
2126         ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2127
2128         /*
2129          * In the origin implementation an overflow is handled by returning a
2130          * search header with a len of zero, so reset ret.
2131          */
2132         if (ret == -EOVERFLOW)
2133                 ret = 0;
2134
2135         if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2136                 ret = -EFAULT;
2137         return ret;
2138 }
2139
2140 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2141                                                void __user *argp)
2142 {
2143         struct btrfs_ioctl_search_args_v2 __user *uarg;
2144         struct btrfs_ioctl_search_args_v2 args;
2145         struct inode *inode;
2146         int ret;
2147         size_t buf_size;
2148         const size_t buf_limit = 16 * 1024 * 1024;
2149
2150         if (!capable(CAP_SYS_ADMIN))
2151                 return -EPERM;
2152
2153         /* copy search header and buffer size */
2154         uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2155         if (copy_from_user(&args, uarg, sizeof(args)))
2156                 return -EFAULT;
2157
2158         buf_size = args.buf_size;
2159
2160         if (buf_size < sizeof(struct btrfs_ioctl_search_header))
2161                 return -EOVERFLOW;
2162
2163         /* limit result size to 16MB */
2164         if (buf_size > buf_limit)
2165                 buf_size = buf_limit;
2166
2167         inode = file_inode(file);
2168         ret = search_ioctl(inode, &args.key, &buf_size,
2169                            (char *)(&uarg->buf[0]));
2170         if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2171                 ret = -EFAULT;
2172         else if (ret == -EOVERFLOW &&
2173                 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2174                 ret = -EFAULT;
2175
2176         return ret;
2177 }
2178
2179 /*
2180  * Search INODE_REFs to identify path name of 'dirid' directory
2181  * in a 'tree_id' tree. and sets path name to 'name'.
2182  */
2183 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2184                                 u64 tree_id, u64 dirid, char *name)
2185 {
2186         struct btrfs_root *root;
2187         struct btrfs_key key;
2188         char *ptr;
2189         int ret = -1;
2190         int slot;
2191         int len;
2192         int total_len = 0;
2193         struct btrfs_inode_ref *iref;
2194         struct extent_buffer *l;
2195         struct btrfs_path *path;
2196
2197         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2198                 name[0]='\0';
2199                 return 0;
2200         }
2201
2202         path = btrfs_alloc_path();
2203         if (!path)
2204                 return -ENOMEM;
2205
2206         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2207
2208         key.objectid = tree_id;
2209         key.type = BTRFS_ROOT_ITEM_KEY;
2210         key.offset = (u64)-1;
2211         root = btrfs_read_fs_root_no_name(info, &key);
2212         if (IS_ERR(root)) {
2213                 printk(KERN_ERR "BTRFS: could not find root %llu\n", tree_id);
2214                 ret = -ENOENT;
2215                 goto out;
2216         }
2217
2218         key.objectid = dirid;
2219         key.type = BTRFS_INODE_REF_KEY;
2220         key.offset = (u64)-1;
2221
2222         while (1) {
2223                 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2224                 if (ret < 0)
2225                         goto out;
2226                 else if (ret > 0) {
2227                         ret = btrfs_previous_item(root, path, dirid,
2228                                                   BTRFS_INODE_REF_KEY);
2229                         if (ret < 0)
2230                                 goto out;
2231                         else if (ret > 0) {
2232                                 ret = -ENOENT;
2233                                 goto out;
2234                         }
2235                 }
2236
2237                 l = path->nodes[0];
2238                 slot = path->slots[0];
2239                 btrfs_item_key_to_cpu(l, &key, slot);
2240
2241                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2242                 len = btrfs_inode_ref_name_len(l, iref);
2243                 ptr -= len + 1;
2244                 total_len += len + 1;
2245                 if (ptr < name) {
2246                         ret = -ENAMETOOLONG;
2247                         goto out;
2248                 }
2249
2250                 *(ptr + len) = '/';
2251                 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2252
2253                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2254                         break;
2255
2256                 btrfs_release_path(path);
2257                 key.objectid = key.offset;
2258                 key.offset = (u64)-1;
2259                 dirid = key.objectid;
2260         }
2261         memmove(name, ptr, total_len);
2262         name[total_len] = '\0';
2263         ret = 0;
2264 out:
2265         btrfs_free_path(path);
2266         return ret;
2267 }
2268
2269 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2270                                            void __user *argp)
2271 {
2272          struct btrfs_ioctl_ino_lookup_args *args;
2273          struct inode *inode;
2274          int ret;
2275
2276         if (!capable(CAP_SYS_ADMIN))
2277                 return -EPERM;
2278
2279         args = memdup_user(argp, sizeof(*args));
2280         if (IS_ERR(args))
2281                 return PTR_ERR(args);
2282
2283         inode = file_inode(file);
2284
2285         if (args->treeid == 0)
2286                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2287
2288         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2289                                         args->treeid, args->objectid,
2290                                         args->name);
2291
2292         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2293                 ret = -EFAULT;
2294
2295         kfree(args);
2296         return ret;
2297 }
2298
2299 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2300                                              void __user *arg)
2301 {
2302         struct dentry *parent = file->f_path.dentry;
2303         struct dentry *dentry;
2304         struct inode *dir = d_inode(parent);
2305         struct inode *inode;
2306         struct btrfs_root *root = BTRFS_I(dir)->root;
2307         struct btrfs_root *dest = NULL;
2308         struct btrfs_ioctl_vol_args *vol_args;
2309         struct btrfs_trans_handle *trans;
2310         struct btrfs_block_rsv block_rsv;
2311         u64 root_flags;
2312         u64 qgroup_reserved;
2313         int namelen;
2314         int ret;
2315         int err = 0;
2316
2317         vol_args = memdup_user(arg, sizeof(*vol_args));
2318         if (IS_ERR(vol_args))
2319                 return PTR_ERR(vol_args);
2320
2321         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2322         namelen = strlen(vol_args->name);
2323         if (strchr(vol_args->name, '/') ||
2324             strncmp(vol_args->name, "..", namelen) == 0) {
2325                 err = -EINVAL;
2326                 goto out;
2327         }
2328
2329         err = mnt_want_write_file(file);
2330         if (err)
2331                 goto out;
2332
2333
2334         err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
2335         if (err == -EINTR)
2336                 goto out_drop_write;
2337         dentry = lookup_one_len(vol_args->name, parent, namelen);
2338         if (IS_ERR(dentry)) {
2339                 err = PTR_ERR(dentry);
2340                 goto out_unlock_dir;
2341         }
2342
2343         if (d_really_is_negative(dentry)) {
2344                 err = -ENOENT;
2345                 goto out_dput;
2346         }
2347
2348         inode = d_inode(dentry);
2349         dest = BTRFS_I(inode)->root;
2350         if (!capable(CAP_SYS_ADMIN)) {
2351                 /*
2352                  * Regular user.  Only allow this with a special mount
2353                  * option, when the user has write+exec access to the
2354                  * subvol root, and when rmdir(2) would have been
2355                  * allowed.
2356                  *
2357                  * Note that this is _not_ check that the subvol is
2358                  * empty or doesn't contain data that we wouldn't
2359                  * otherwise be able to delete.
2360                  *
2361                  * Users who want to delete empty subvols should try
2362                  * rmdir(2).
2363                  */
2364                 err = -EPERM;
2365                 if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
2366                         goto out_dput;
2367
2368                 /*
2369                  * Do not allow deletion if the parent dir is the same
2370                  * as the dir to be deleted.  That means the ioctl
2371                  * must be called on the dentry referencing the root
2372                  * of the subvol, not a random directory contained
2373                  * within it.
2374                  */
2375                 err = -EINVAL;
2376                 if (root == dest)
2377                         goto out_dput;
2378
2379                 err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2380                 if (err)
2381                         goto out_dput;
2382         }
2383
2384         /* check if subvolume may be deleted by a user */
2385         err = btrfs_may_delete(dir, dentry, 1);
2386         if (err)
2387                 goto out_dput;
2388
2389         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2390                 err = -EINVAL;
2391                 goto out_dput;
2392         }
2393
2394         mutex_lock(&inode->i_mutex);
2395
2396         /*
2397          * Don't allow to delete a subvolume with send in progress. This is
2398          * inside the i_mutex so the error handling that has to drop the bit
2399          * again is not run concurrently.
2400          */
2401         spin_lock(&dest->root_item_lock);
2402         root_flags = btrfs_root_flags(&dest->root_item);
2403         if (dest->send_in_progress == 0) {
2404                 btrfs_set_root_flags(&dest->root_item,
2405                                 root_flags | BTRFS_ROOT_SUBVOL_DEAD);
2406                 spin_unlock(&dest->root_item_lock);
2407         } else {
2408                 spin_unlock(&dest->root_item_lock);
2409                 btrfs_warn(root->fs_info,
2410                         "Attempt to delete subvolume %llu during send",
2411                         dest->root_key.objectid);
2412                 err = -EPERM;
2413                 goto out_unlock_inode;
2414         }
2415
2416         d_invalidate(dentry);
2417
2418         down_write(&root->fs_info->subvol_sem);
2419
2420         err = may_destroy_subvol(dest);
2421         if (err)
2422                 goto out_up_write;
2423
2424         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
2425         /*
2426          * One for dir inode, two for dir entries, two for root
2427          * ref/backref.
2428          */
2429         err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2430                                                5, &qgroup_reserved, true);
2431         if (err)
2432                 goto out_up_write;
2433
2434         trans = btrfs_start_transaction(root, 0);
2435         if (IS_ERR(trans)) {
2436                 err = PTR_ERR(trans);
2437                 goto out_release;
2438         }
2439         trans->block_rsv = &block_rsv;
2440         trans->bytes_reserved = block_rsv.size;
2441
2442         ret = btrfs_unlink_subvol(trans, root, dir,
2443                                 dest->root_key.objectid,
2444                                 dentry->d_name.name,
2445                                 dentry->d_name.len);
2446         if (ret) {
2447                 err = ret;
2448                 btrfs_abort_transaction(trans, root, ret);
2449                 goto out_end_trans;
2450         }
2451
2452         btrfs_record_root_in_trans(trans, dest);
2453
2454         memset(&dest->root_item.drop_progress, 0,
2455                 sizeof(dest->root_item.drop_progress));
2456         dest->root_item.drop_level = 0;
2457         btrfs_set_root_refs(&dest->root_item, 0);
2458
2459         if (!test_and_set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &dest->state)) {
2460                 ret = btrfs_insert_orphan_item(trans,
2461                                         root->fs_info->tree_root,
2462                                         dest->root_key.objectid);
2463                 if (ret) {
2464                         btrfs_abort_transaction(trans, root, ret);
2465                         err = ret;
2466                         goto out_end_trans;
2467                 }
2468         }
2469
2470         ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2471                                   dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
2472                                   dest->root_key.objectid);
2473         if (ret && ret != -ENOENT) {
2474                 btrfs_abort_transaction(trans, root, ret);
2475                 err = ret;
2476                 goto out_end_trans;
2477         }
2478         if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
2479                 ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
2480                                           dest->root_item.received_uuid,
2481                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
2482                                           dest->root_key.objectid);
2483                 if (ret && ret != -ENOENT) {
2484                         btrfs_abort_transaction(trans, root, ret);
2485                         err = ret;
2486                         goto out_end_trans;
2487                 }
2488         }
2489
2490 out_end_trans:
2491         trans->block_rsv = NULL;
2492         trans->bytes_reserved = 0;
2493         ret = btrfs_end_transaction(trans, root);
2494         if (ret && !err)
2495                 err = ret;
2496         inode->i_flags |= S_DEAD;
2497 out_release:
2498         btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2499 out_up_write:
2500         up_write(&root->fs_info->subvol_sem);
2501         if (err) {
2502                 spin_lock(&dest->root_item_lock);
2503                 root_flags = btrfs_root_flags(&dest->root_item);
2504                 btrfs_set_root_flags(&dest->root_item,
2505                                 root_flags & ~BTRFS_ROOT_SUBVOL_DEAD);
2506                 spin_unlock(&dest->root_item_lock);
2507         }
2508 out_unlock_inode:
2509         mutex_unlock(&inode->i_mutex);
2510         if (!err) {
2511                 shrink_dcache_sb(root->fs_info->sb);
2512                 btrfs_invalidate_inodes(dest);
2513                 d_delete(dentry);
2514                 ASSERT(dest->send_in_progress == 0);
2515
2516                 /* the last ref */
2517                 if (dest->ino_cache_inode) {
2518                         iput(dest->ino_cache_inode);
2519                         dest->ino_cache_inode = NULL;
2520                 }
2521         }
2522 out_dput:
2523         dput(dentry);
2524 out_unlock_dir:
2525         mutex_unlock(&dir->i_mutex);
2526 out_drop_write:
2527         mnt_drop_write_file(file);
2528 out:
2529         kfree(vol_args);
2530         return err;
2531 }
2532
2533 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2534 {
2535         struct inode *inode = file_inode(file);
2536         struct btrfs_root *root = BTRFS_I(inode)->root;
2537         struct btrfs_ioctl_defrag_range_args *range;
2538         int ret;
2539
2540         ret = mnt_want_write_file(file);
2541         if (ret)
2542                 return ret;
2543
2544         if (btrfs_root_readonly(root)) {
2545                 ret = -EROFS;
2546                 goto out;
2547         }
2548
2549         switch (inode->i_mode & S_IFMT) {
2550         case S_IFDIR:
2551                 if (!capable(CAP_SYS_ADMIN)) {
2552                         ret = -EPERM;
2553                         goto out;
2554                 }
2555                 ret = btrfs_defrag_root(root);
2556                 if (ret)
2557                         goto out;
2558                 ret = btrfs_defrag_root(root->fs_info->extent_root);
2559                 break;
2560         case S_IFREG:
2561                 if (!(file->f_mode & FMODE_WRITE)) {
2562                         ret = -EINVAL;
2563                         goto out;
2564                 }
2565
2566                 range = kzalloc(sizeof(*range), GFP_KERNEL);
2567                 if (!range) {
2568                         ret = -ENOMEM;
2569                         goto out;
2570                 }
2571
2572                 if (argp) {
2573                         if (copy_from_user(range, argp,
2574                                            sizeof(*range))) {
2575                                 ret = -EFAULT;
2576                                 kfree(range);
2577                                 goto out;
2578                         }
2579                         /* compression requires us to start the IO */
2580                         if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2581                                 range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2582                                 range->extent_thresh = (u32)-1;
2583                         }
2584                 } else {
2585                         /* the rest are all set to zero by kzalloc */
2586                         range->len = (u64)-1;
2587                 }
2588                 ret = btrfs_defrag_file(file_inode(file), file,
2589                                         range, 0, 0);
2590                 if (ret > 0)
2591                         ret = 0;
2592                 kfree(range);
2593                 break;
2594         default:
2595                 ret = -EINVAL;
2596         }
2597 out:
2598         mnt_drop_write_file(file);
2599         return ret;
2600 }
2601
2602 static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2603 {
2604         struct btrfs_ioctl_vol_args *vol_args;
2605         int ret;
2606
2607         if (!capable(CAP_SYS_ADMIN))
2608                 return -EPERM;
2609
2610         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2611                         1)) {
2612                 return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2613         }
2614
2615         mutex_lock(&root->fs_info->volume_mutex);
2616         vol_args = memdup_user(arg, sizeof(*vol_args));
2617         if (IS_ERR(vol_args)) {
2618                 ret = PTR_ERR(vol_args);
2619                 goto out;
2620         }
2621
2622         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2623         ret = btrfs_init_new_device(root, vol_args->name);
2624
2625         if (!ret)
2626                 btrfs_info(root->fs_info, "disk added %s",vol_args->name);
2627
2628         kfree(vol_args);
2629 out:
2630         mutex_unlock(&root->fs_info->volume_mutex);
2631         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2632         return ret;
2633 }
2634
2635 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2636 {
2637         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
2638         struct btrfs_ioctl_vol_args *vol_args;
2639         int ret;
2640
2641         if (!capable(CAP_SYS_ADMIN))
2642                 return -EPERM;
2643
2644         ret = mnt_want_write_file(file);
2645         if (ret)
2646                 return ret;
2647
2648         vol_args = memdup_user(arg, sizeof(*vol_args));
2649         if (IS_ERR(vol_args)) {
2650                 ret = PTR_ERR(vol_args);
2651                 goto err_drop;
2652         }
2653
2654         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2655
2656         if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
2657                         1)) {
2658                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2659                 goto out;
2660         }
2661
2662         mutex_lock(&root->fs_info->volume_mutex);
2663         ret = btrfs_rm_device(root, vol_args->name);
2664         mutex_unlock(&root->fs_info->volume_mutex);
2665         atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2666
2667         if (!ret)
2668                 btrfs_info(root->fs_info, "disk deleted %s",vol_args->name);
2669
2670 out:
2671         kfree(vol_args);
2672 err_drop:
2673         mnt_drop_write_file(file);
2674         return ret;
2675 }
2676
2677 static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
2678 {
2679         struct btrfs_ioctl_fs_info_args *fi_args;
2680         struct btrfs_device *device;
2681         struct btrfs_device *next;
2682         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2683         int ret = 0;
2684
2685         fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2686         if (!fi_args)
2687                 return -ENOMEM;
2688
2689         mutex_lock(&fs_devices->device_list_mutex);
2690         fi_args->num_devices = fs_devices->num_devices;
2691         memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2692
2693         list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2694                 if (device->devid > fi_args->max_id)
2695                         fi_args->max_id = device->devid;
2696         }
2697         mutex_unlock(&fs_devices->device_list_mutex);
2698
2699         fi_args->nodesize = root->fs_info->super_copy->nodesize;
2700         fi_args->sectorsize = root->fs_info->super_copy->sectorsize;
2701         fi_args->clone_alignment = root->fs_info->super_copy->sectorsize;
2702
2703         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2704                 ret = -EFAULT;
2705
2706         kfree(fi_args);
2707         return ret;
2708 }
2709
2710 static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
2711 {
2712         struct btrfs_ioctl_dev_info_args *di_args;
2713         struct btrfs_device *dev;
2714         struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2715         int ret = 0;
2716         char *s_uuid = NULL;
2717
2718         di_args = memdup_user(arg, sizeof(*di_args));
2719         if (IS_ERR(di_args))
2720                 return PTR_ERR(di_args);
2721
2722         if (!btrfs_is_empty_uuid(di_args->uuid))
2723                 s_uuid = di_args->uuid;
2724
2725         mutex_lock(&fs_devices->device_list_mutex);
2726         dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
2727
2728         if (!dev) {
2729                 ret = -ENODEV;
2730                 goto out;
2731         }
2732
2733         di_args->devid = dev->devid;
2734         di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2735         di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2736         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2737         if (dev->name) {
2738                 struct rcu_string *name;
2739
2740                 rcu_read_lock();
2741                 name = rcu_dereference(dev->name);
2742                 strncpy(di_args->path, name->str, sizeof(di_args->path));
2743                 rcu_read_unlock();
2744                 di_args->path[sizeof(di_args->path) - 1] = 0;
2745         } else {
2746                 di_args->path[0] = '\0';
2747         }
2748
2749 out:
2750         mutex_unlock(&fs_devices->device_list_mutex);
2751         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2752                 ret = -EFAULT;
2753
2754         kfree(di_args);
2755         return ret;
2756 }
2757
2758 static struct page *extent_same_get_page(struct inode *inode, u64 off)
2759 {
2760         struct page *page;
2761         pgoff_t index;
2762         struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
2763
2764         index = off >> PAGE_CACHE_SHIFT;
2765
2766         page = grab_cache_page(inode->i_mapping, index);
2767         if (!page)
2768                 return NULL;
2769
2770         if (!PageUptodate(page)) {
2771                 if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
2772                                                  0))
2773                         return NULL;
2774                 lock_page(page);
2775                 if (!PageUptodate(page)) {
2776                         unlock_page(page);
2777                         page_cache_release(page);
2778                         return NULL;
2779                 }
2780         }
2781         unlock_page(page);
2782
2783         return page;
2784 }
2785
2786 static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
2787 {
2788         /* do any pending delalloc/csum calc on src, one way or
2789            another, and lock file content */
2790         while (1) {
2791                 struct btrfs_ordered_extent *ordered;
2792                 lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2793                 ordered = btrfs_lookup_first_ordered_extent(inode,
2794                                                             off + len - 1);
2795                 if ((!ordered ||
2796                      ordered->file_offset + ordered->len <= off ||
2797                      ordered->file_offset >= off + len) &&
2798                     !test_range_bit(&BTRFS_I(inode)->io_tree, off,
2799                                     off + len - 1, EXTENT_DELALLOC, 0, NULL)) {
2800                         if (ordered)
2801                                 btrfs_put_ordered_extent(ordered);
2802                         break;
2803                 }
2804                 unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
2805                 if (ordered)
2806                         btrfs_put_ordered_extent(ordered);
2807                 btrfs_wait_ordered_range(inode, off, len);
2808         }
2809 }
2810
2811 static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
2812                                 struct inode *inode2, u64 loff2, u64 len)
2813 {
2814         unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
2815         unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);
2816
2817         mutex_unlock(&inode1->i_mutex);
2818         mutex_unlock(&inode2->i_mutex);
2819 }
2820
2821 static void btrfs_double_lock(struct inode *inode1, u64 loff1,
2822                               struct inode *inode2, u64 loff2, u64 len)
2823 {
2824         if (inode1 < inode2) {
2825                 swap(inode1, inode2);
2826                 swap(loff1, loff2);
2827         }
2828
2829         mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
2830         lock_extent_range(inode1, loff1, len);
2831         if (inode1 != inode2) {
2832                 mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
2833                 lock_extent_range(inode2, loff2, len);
2834         }
2835 }
2836
2837 static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
2838                           u64 dst_loff, u64 len)
2839 {
2840         int ret = 0;
2841         struct page *src_page, *dst_page;
2842         unsigned int cmp_len = PAGE_CACHE_SIZE;
2843         void *addr, *dst_addr;
2844
2845         while (len) {
2846                 if (len < PAGE_CACHE_SIZE)
2847                         cmp_len = len;
2848
2849                 src_page = extent_same_get_page(src, loff);
2850                 if (!src_page)
2851                         return -EINVAL;
2852                 dst_page = extent_same_get_page(dst, dst_loff);
2853                 if (!dst_page) {
2854                         page_cache_release(src_page);
2855                         return -EINVAL;
2856                 }
2857                 addr = kmap_atomic(src_page);
2858                 dst_addr = kmap_atomic(dst_page);
2859
2860                 flush_dcache_page(src_page);
2861                 flush_dcache_page(dst_page);
2862
2863                 if (memcmp(addr, dst_addr, cmp_len))
2864                         ret = BTRFS_SAME_DATA_DIFFERS;
2865
2866                 kunmap_atomic(addr);
2867                 kunmap_atomic(dst_addr);
2868                 page_cache_release(src_page);
2869                 page_cache_release(dst_page);
2870
2871                 if (ret)
2872                         break;
2873
2874                 loff += cmp_len;
2875                 dst_loff += cmp_len;
2876                 len -= cmp_len;
2877         }
2878
2879         return ret;
2880 }
2881
2882 static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
2883 {
2884         u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;
2885
2886         if (off + len > inode->i_size || off + len < off)
2887                 return -EINVAL;
2888         /* Check that we are block aligned - btrfs_clone() requires this */
2889         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
2890                 return -EINVAL;
2891
2892         return 0;
2893 }
2894
2895 static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
2896                              struct inode *dst, u64 dst_loff)
2897 {
2898         int ret;
2899
2900         /*
2901          * btrfs_clone() can't handle extents in the same file
2902          * yet. Once that works, we can drop this check and replace it
2903          * with a check for the same inode, but overlapping extents.
2904          */
2905         if (src == dst)
2906                 return -EINVAL;
2907
2908         if (len == 0)
2909                 return 0;
2910
2911         btrfs_double_lock(src, loff, dst, dst_loff, len);
2912
2913         ret = extent_same_check_offsets(src, loff, len);
2914         if (ret)
2915                 goto out_unlock;
2916
2917         ret = extent_same_check_offsets(dst, dst_loff, len);
2918         if (ret)
2919                 goto out_unlock;
2920
2921         /* don't make the dst file partly checksummed */
2922         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2923             (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
2924                 ret = -EINVAL;
2925                 goto out_unlock;
2926         }
2927
2928         ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
2929         if (ret == 0)
2930                 ret = btrfs_clone(src, dst, loff, len, len, dst_loff);
2931
2932 out_unlock:
2933         btrfs_double_unlock(src, loff, dst, dst_loff, len);
2934
2935         return ret;
2936 }
2937
2938 #define BTRFS_MAX_DEDUPE_LEN    (16 * 1024 * 1024)
2939
2940 static long btrfs_ioctl_file_extent_same(struct file *file,
2941                         struct btrfs_ioctl_same_args __user *argp)
2942 {
2943         struct btrfs_ioctl_same_args *same;
2944         struct btrfs_ioctl_same_extent_info *info;
2945         struct inode *src = file_inode(file);
2946         u64 off;
2947         u64 len;
2948         int i;
2949         int ret;
2950         unsigned long size;
2951         u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
2952         bool is_admin = capable(CAP_SYS_ADMIN);
2953         u16 count;
2954
2955         if (!(file->f_mode & FMODE_READ))
2956                 return -EINVAL;
2957
2958         ret = mnt_want_write_file(file);
2959         if (ret)
2960                 return ret;
2961
2962         if (get_user(count, &argp->dest_count)) {
2963                 ret = -EFAULT;
2964                 goto out;
2965         }
2966
2967         size = offsetof(struct btrfs_ioctl_same_args __user, info[count]);
2968
2969         same = memdup_user(argp, size);
2970
2971         if (IS_ERR(same)) {
2972                 ret = PTR_ERR(same);
2973                 goto out;
2974         }
2975
2976         off = same->logical_offset;
2977         len = same->length;
2978
2979         /*
2980          * Limit the total length we will dedupe for each operation.
2981          * This is intended to bound the total time spent in this
2982          * ioctl to something sane.
2983          */
2984         if (len > BTRFS_MAX_DEDUPE_LEN)
2985                 len = BTRFS_MAX_DEDUPE_LEN;
2986
2987         if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
2988                 /*
2989                  * Btrfs does not support blocksize < page_size. As a
2990                  * result, btrfs_cmp_data() won't correctly handle
2991                  * this situation without an update.
2992                  */
2993                 ret = -EINVAL;
2994                 goto out;
2995         }
2996
2997         ret = -EISDIR;
2998         if (S_ISDIR(src->i_mode))
2999                 goto out;
3000
3001         ret = -EACCES;
3002         if (!S_ISREG(src->i_mode))
3003                 goto out;
3004
3005         /* pre-format output fields to sane values */
3006         for (i = 0; i < count; i++) {
3007                 same->info[i].bytes_deduped = 0ULL;
3008                 same->info[i].status = 0;
3009         }
3010
3011         for (i = 0, info = same->info; i < count; i++, info++) {
3012                 struct inode *dst;
3013                 struct fd dst_file = fdget(info->fd);
3014                 if (!dst_file.file) {
3015                         info->status = -EBADF;
3016                         continue;
3017                 }
3018                 dst = file_inode(dst_file.file);
3019
3020                 if (!(is_admin || (dst_file.file->f_mode & FMODE_WRITE))) {
3021                         info->status = -EINVAL;
3022                 } else if (file->f_path.mnt != dst_file.file->f_path.mnt) {
3023                         info->status = -EXDEV;
3024                 } else if (S_ISDIR(dst->i_mode)) {
3025                         info->status = -EISDIR;
3026                 } else if (!S_ISREG(dst->i_mode)) {
3027                         info->status = -EACCES;
3028                 } else {
3029                         info->status = btrfs_extent_same(src, off, len, dst,
3030                                                         info->logical_offset);
3031                         if (info->status == 0)
3032                                 info->bytes_deduped += len;
3033                 }
3034                 fdput(dst_file);
3035         }
3036
3037         ret = copy_to_user(argp, same, size);
3038         if (ret)
3039                 ret = -EFAULT;
3040
3041 out:
3042         mnt_drop_write_file(file);
3043         return ret;
3044 }
3045
3046 /* Helper to check and see if this root currently has a ref on the given disk
3047  * bytenr.  If it does then we need to update the quota for this root.  This
3048  * doesn't do anything if quotas aren't enabled.
3049  */
3050 static int check_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
3051                      u64 disko)
3052 {
3053         struct seq_list tree_mod_seq_elem = SEQ_LIST_INIT(tree_mod_seq_elem);
3054         struct ulist *roots;
3055         struct ulist_iterator uiter;
3056         struct ulist_node *root_node = NULL;
3057         int ret;
3058
3059         if (!root->fs_info->quota_enabled)
3060                 return 1;
3061
3062         btrfs_get_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3063         ret = btrfs_find_all_roots(trans, root->fs_info, disko,
3064                                    tree_mod_seq_elem.seq, &roots);
3065         if (ret < 0)
3066                 goto out;
3067         ret = 0;
3068         ULIST_ITER_INIT(&uiter);
3069         while ((root_node = ulist_next(roots, &uiter))) {
3070                 if (root_node->val == root->objectid) {
3071                         ret = 1;
3072                         break;
3073                 }
3074         }
3075         ulist_free(roots);
3076 out:
3077         btrfs_put_tree_mod_seq(root->fs_info, &tree_mod_seq_elem);
3078         return ret;
3079 }
3080
3081 static int clone_finish_inode_update(struct btrfs_trans_handle *trans,
3082                                      struct inode *inode,
3083                                      u64 endoff,
3084                                      const u64 destoff,
3085                                      const u64 olen)
3086 {
3087         struct btrfs_root *root = BTRFS_I(inode)->root;
3088         int ret;
3089
3090         inode_inc_iversion(inode);
3091         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3092         /*
3093          * We round up to the block size at eof when determining which
3094          * extents to clone above, but shouldn't round up the file size.
3095          */
3096         if (endoff > destoff + olen)
3097                 endoff = destoff + olen;
3098         if (endoff > inode->i_size)
3099                 btrfs_i_size_write(inode, endoff);
3100
3101         ret = btrfs_update_inode(trans, root, inode);
3102         if (ret) {
3103                 btrfs_abort_transaction(trans, root, ret);
3104                 btrfs_end_transaction(trans, root);
3105                 goto out;
3106         }
3107         ret = btrfs_end_transaction(trans, root);
3108 out:
3109         return ret;
3110 }
3111
3112 static void clone_update_extent_map(struct inode *inode,
3113                                     const struct btrfs_trans_handle *trans,
3114                                     const struct btrfs_path *path,
3115                                     const u64 hole_offset,
3116                                     const u64 hole_len)
3117 {
3118         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3119         struct extent_map *em;
3120         int ret;
3121
3122         em = alloc_extent_map();
3123         if (!em) {
3124                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3125                         &BTRFS_I(inode)->runtime_flags);
3126                 return;
3127         }
3128
3129         if (path) {
3130                 struct btrfs_file_extent_item *fi;
3131
3132                 fi = btrfs_item_ptr(path->nodes[0], path->slots[0],
3133                                     struct btrfs_file_extent_item);
3134                 btrfs_extent_item_to_extent_map(inode, path, fi, false, em);
3135                 em->generation = -1;
3136                 if (btrfs_file_extent_type(path->nodes[0], fi) ==
3137                     BTRFS_FILE_EXTENT_INLINE)
3138                         set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3139                                 &BTRFS_I(inode)->runtime_flags);
3140         } else {
3141                 em->start = hole_offset;
3142                 em->len = hole_len;
3143                 em->ram_bytes = em->len;
3144                 em->orig_start = hole_offset;
3145                 em->block_start = EXTENT_MAP_HOLE;
3146                 em->block_len = 0;
3147                 em->orig_block_len = 0;
3148                 em->compress_type = BTRFS_COMPRESS_NONE;
3149                 em->generation = trans->transid;
3150         }
3151
3152         while (1) {
3153                 write_lock(&em_tree->lock);
3154                 ret = add_extent_mapping(em_tree, em, 1);
3155                 write_unlock(&em_tree->lock);
3156                 if (ret != -EEXIST) {
3157                         free_extent_map(em);
3158                         break;
3159                 }
3160                 btrfs_drop_extent_cache(inode, em->start,
3161                                         em->start + em->len - 1, 0);
3162         }
3163
3164         if (ret)
3165                 set_bit(BTRFS_INODE_NEEDS_FULL_SYNC,
3166                         &BTRFS_I(inode)->runtime_flags);
3167 }
3168
3169 /**
3170  * btrfs_clone() - clone a range from inode file to another
3171  *
3172  * @src: Inode to clone from
3173  * @inode: Inode to clone to
3174  * @off: Offset within source to start clone from
3175  * @olen: Original length, passed by user, of range to clone
3176  * @olen_aligned: Block-aligned value of olen, extent_same uses
3177  *               identical values here
3178  * @destoff: Offset within @inode to start clone
3179  */
3180 static int btrfs_clone(struct inode *src, struct inode *inode,
3181                        const u64 off, const u64 olen, const u64 olen_aligned,
3182                        const u64 destoff)
3183 {
3184         struct btrfs_root *root = BTRFS_I(inode)->root;
3185         struct btrfs_path *path = NULL;
3186         struct extent_buffer *leaf;
3187         struct btrfs_trans_handle *trans;
3188         char *buf = NULL;
3189         struct btrfs_key key;
3190         u32 nritems;
3191         int slot;
3192         int ret;
3193         int no_quota;
3194         const u64 len = olen_aligned;
3195         u64 last_disko = 0;
3196         u64 last_dest_end = destoff;
3197
3198         ret = -ENOMEM;
3199         buf = vmalloc(root->nodesize);
3200         if (!buf)
3201                 return ret;
3202
3203         path = btrfs_alloc_path();
3204         if (!path) {
3205                 vfree(buf);
3206                 return ret;
3207         }
3208
3209         path->reada = 2;
3210         /* clone data */
3211         key.objectid = btrfs_ino(src);
3212         key.type = BTRFS_EXTENT_DATA_KEY;
3213         key.offset = off;
3214
3215         while (1) {
3216                 u64 next_key_min_offset = key.offset + 1;
3217
3218                 /*
3219                  * note the key will change type as we walk through the
3220                  * tree.
3221                  */
3222                 path->leave_spinning = 1;
3223                 ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
3224                                 0, 0);
3225                 if (ret < 0)
3226                         goto out;
3227                 /*
3228                  * First search, if no extent item that starts at offset off was
3229                  * found but the previous item is an extent item, it's possible
3230                  * it might overlap our target range, therefore process it.
3231                  */
3232                 if (key.offset == off && ret > 0 && path->slots[0] > 0) {
3233                         btrfs_item_key_to_cpu(path->nodes[0], &key,
3234                                               path->slots[0] - 1);
3235                         if (key.type == BTRFS_EXTENT_DATA_KEY)
3236                                 path->slots[0]--;
3237                 }
3238
3239                 nritems = btrfs_header_nritems(path->nodes[0]);
3240 process_slot:
3241                 no_quota = 1;
3242                 if (path->slots[0] >= nritems) {
3243                         ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
3244                         if (ret < 0)
3245                                 goto out;
3246                         if (ret > 0)
3247                                 break;
3248                         nritems = btrfs_header_nritems(path->nodes[0]);
3249                 }
3250                 leaf = path->nodes[0];
3251                 slot = path->slots[0];
3252
3253                 btrfs_item_key_to_cpu(leaf, &key, slot);
3254                 if (key.type > BTRFS_EXTENT_DATA_KEY ||
3255                     key.objectid != btrfs_ino(src))
3256                         break;
3257
3258                 if (key.type == BTRFS_EXTENT_DATA_KEY) {
3259                         struct btrfs_file_extent_item *extent;
3260                         int type;
3261                         u32 size;
3262                         struct btrfs_key new_key;
3263                         u64 disko = 0, diskl = 0;
3264                         u64 datao = 0, datal = 0;
3265                         u8 comp;
3266                         u64 drop_start;
3267
3268                         extent = btrfs_item_ptr(leaf, slot,
3269                                                 struct btrfs_file_extent_item);
3270                         comp = btrfs_file_extent_compression(leaf, extent);
3271                         type = btrfs_file_extent_type(leaf, extent);
3272                         if (type == BTRFS_FILE_EXTENT_REG ||
3273                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3274                                 disko = btrfs_file_extent_disk_bytenr(leaf,
3275                                                                       extent);
3276                                 diskl = btrfs_file_extent_disk_num_bytes(leaf,
3277                                                                  extent);
3278                                 datao = btrfs_file_extent_offset(leaf, extent);
3279                                 datal = btrfs_file_extent_num_bytes(leaf,
3280                                                                     extent);
3281                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3282                                 /* take upper bound, may be compressed */
3283                                 datal = btrfs_file_extent_ram_bytes(leaf,
3284                                                                     extent);
3285                         }
3286
3287                         /*
3288                          * The first search might have left us at an extent
3289                          * item that ends before our target range's start, can
3290                          * happen if we have holes and NO_HOLES feature enabled.
3291                          */
3292                         if (key.offset + datal <= off) {
3293                                 path->slots[0]++;
3294                                 goto process_slot;
3295                         } else if (key.offset >= off + len) {
3296                                 break;
3297                         }
3298                         next_key_min_offset = key.offset + datal;
3299                         size = btrfs_item_size_nr(leaf, slot);
3300                         read_extent_buffer(leaf, buf,
3301                                            btrfs_item_ptr_offset(leaf, slot),
3302                                            size);
3303
3304                         btrfs_release_path(path);
3305                         path->leave_spinning = 0;
3306
3307                         memcpy(&new_key, &key, sizeof(new_key));
3308                         new_key.objectid = btrfs_ino(inode);
3309                         if (off <= key.offset)
3310                                 new_key.offset = key.offset + destoff - off;
3311                         else
3312                                 new_key.offset = destoff;
3313
3314                         /*
3315                          * Deal with a hole that doesn't have an extent item
3316                          * that represents it (NO_HOLES feature enabled).
3317                          * This hole is either in the middle of the cloning
3318                          * range or at the beginning (fully overlaps it or
3319                          * partially overlaps it).
3320                          */
3321                         if (new_key.offset != last_dest_end)
3322                                 drop_start = last_dest_end;
3323                         else
3324                                 drop_start = new_key.offset;
3325
3326                         /*
3327                          * 1 - adjusting old extent (we may have to split it)
3328                          * 1 - add new extent
3329                          * 1 - inode update
3330                          */
3331                         trans = btrfs_start_transaction(root, 3);
3332                         if (IS_ERR(trans)) {
3333                                 ret = PTR_ERR(trans);
3334                                 goto out;
3335                         }
3336
3337                         if (type == BTRFS_FILE_EXTENT_REG ||
3338                             type == BTRFS_FILE_EXTENT_PREALLOC) {
3339                                 /*
3340                                  *    a  | --- range to clone ---|  b
3341                                  * | ------------- extent ------------- |
3342                                  */
3343
3344                                 /* subtract range b */
3345                                 if (key.offset + datal > off + len)
3346                                         datal = off + len - key.offset;
3347
3348                                 /* subtract range a */
3349                                 if (off > key.offset) {
3350                                         datao += off - key.offset;
3351                                         datal -= off - key.offset;
3352                                 }
3353
3354                                 ret = btrfs_drop_extents(trans, root, inode,
3355                                                          drop_start,
3356                                                          new_key.offset + datal,
3357                                                          1);
3358                                 if (ret) {
3359                                         if (ret != -EOPNOTSUPP)
3360                                                 btrfs_abort_transaction(trans,
3361                                                                 root, ret);
3362                                         btrfs_end_transaction(trans, root);
3363                                         goto out;
3364                                 }
3365
3366                                 ret = btrfs_insert_empty_item(trans, root, path,
3367                                                               &new_key, size);
3368                                 if (ret) {
3369                                         btrfs_abort_transaction(trans, root,
3370                                                                 ret);
3371                                         btrfs_end_transaction(trans, root);
3372                                         goto out;
3373                                 }
3374
3375                                 leaf = path->nodes[0];
3376                                 slot = path->slots[0];
3377                                 write_extent_buffer(leaf, buf,
3378                                             btrfs_item_ptr_offset(leaf, slot),
3379                                             size);
3380
3381                                 extent = btrfs_item_ptr(leaf, slot,
3382                                                 struct btrfs_file_extent_item);
3383
3384                                 /* disko == 0 means it's a hole */
3385                                 if (!disko)
3386                                         datao = 0;
3387
3388                                 btrfs_set_file_extent_offset(leaf, extent,
3389                                                              datao);
3390                                 btrfs_set_file_extent_num_bytes(leaf, extent,
3391                                                                 datal);
3392
3393                                 /*
3394                                  * We need to look up the roots that point at
3395                                  * this bytenr and see if the new root does.  If
3396                                  * it does not we need to make sure we update
3397                                  * quotas appropriately.
3398                                  */
3399                                 if (disko && root != BTRFS_I(src)->root &&
3400                                     disko != last_disko) {
3401                                         no_quota = check_ref(trans, root,
3402                                                              disko);
3403                                         if (no_quota < 0) {
3404                                                 btrfs_abort_transaction(trans,
3405                                                                         root,
3406                                                                         ret);
3407                                                 btrfs_end_transaction(trans,
3408                                                                       root);
3409                                                 ret = no_quota;
3410                                                 goto out;
3411                                         }
3412                                 }
3413
3414                                 if (disko) {
3415                                         inode_add_bytes(inode, datal);
3416                                         ret = btrfs_inc_extent_ref(trans, root,
3417                                                         disko, diskl, 0,
3418                                                         root->root_key.objectid,
3419                                                         btrfs_ino(inode),
3420                                                         new_key.offset - datao,
3421                                                         no_quota);
3422                                         if (ret) {
3423                                                 btrfs_abort_transaction(trans,
3424                                                                         root,
3425                                                                         ret);
3426                                                 btrfs_end_transaction(trans,
3427                                                                       root);
3428                                                 goto out;
3429
3430                                         }
3431                                 }
3432                         } else if (type == BTRFS_FILE_EXTENT_INLINE) {
3433                                 u64 skip = 0;
3434                                 u64 trim = 0;
3435                                 u64 aligned_end = 0;
3436
3437                                 if (off > key.offset) {
3438                                         skip = off - key.offset;
3439                                         new_key.offset += skip;
3440                                 }
3441
3442                                 if (key.offset + datal > off + len)
3443                                         trim = key.offset + datal - (off + len);
3444
3445                                 if (comp && (skip || trim)) {
3446                                         ret = -EINVAL;
3447                                         btrfs_end_transaction(trans, root);
3448                                         goto out;
3449                                 }
3450                                 size -= skip + trim;
3451                                 datal -= skip + trim;
3452
3453                                 aligned_end = ALIGN(new_key.offset + datal,
3454                                                     root->sectorsize);
3455                                 ret = btrfs_drop_extents(trans, root, inode,
3456                                                          drop_start,
3457                                                          aligned_end,
3458                                                          1);
3459                                 if (ret) {
3460                                         if (ret != -EOPNOTSUPP)
3461                                                 btrfs_abort_transaction(trans,
3462                                                         root, ret);
3463                                         btrfs_end_transaction(trans, root);
3464                                         goto out;
3465                                 }
3466
3467                                 ret = btrfs_insert_empty_item(trans, root, path,
3468                                                               &new_key, size);
3469                                 if (ret) {
3470                                         btrfs_abort_transaction(trans, root,
3471                                                                 ret);
3472                                         btrfs_end_transaction(trans, root);
3473                                         goto out;
3474                                 }
3475
3476                                 if (skip) {
3477                                         u32 start =
3478                                           btrfs_file_extent_calc_inline_size(0);
3479                                         memmove(buf+start, buf+start+skip,
3480                                                 datal);
3481                                 }
3482
3483                                 leaf = path->nodes[0];
3484                                 slot = path->slots[0];
3485                                 write_extent_buffer(leaf, buf,
3486                                             btrfs_item_ptr_offset(leaf, slot),
3487                                             size);
3488                                 inode_add_bytes(inode, datal);
3489                         }
3490
3491                         /* If we have an implicit hole (NO_HOLES feature). */
3492                         if (drop_start < new_key.offset)
3493                                 clone_update_extent_map(inode, trans,
3494                                                 NULL, drop_start,
3495                                                 new_key.offset - drop_start);
3496
3497                         clone_update_extent_map(inode, trans, path, 0, 0);
3498
3499                         btrfs_mark_buffer_dirty(leaf);
3500                         btrfs_release_path(path);
3501
3502                         last_dest_end = ALIGN(new_key.offset + datal,
3503                                               root->sectorsize);
3504                         ret = clone_finish_inode_update(trans, inode,
3505                                                         last_dest_end,
3506                                                         destoff, olen);
3507                         if (ret)
3508                                 goto out;
3509                         if (new_key.offset + datal >= destoff + len)
3510                                 break;
3511                 }
3512                 btrfs_release_path(path);
3513                 key.offset = next_key_min_offset;
3514         }
3515         ret = 0;
3516
3517         if (last_dest_end < destoff + len) {
3518                 /*
3519                  * We have an implicit hole (NO_HOLES feature is enabled) that
3520                  * fully or partially overlaps our cloning range at its end.
3521                  */
3522                 btrfs_release_path(path);
3523
3524                 /*
3525                  * 1 - remove extent(s)
3526                  * 1 - inode update
3527                  */
3528                 trans = btrfs_start_transaction(root, 2);
3529                 if (IS_ERR(trans)) {
3530                         ret = PTR_ERR(trans);
3531                         goto out;
3532                 }
3533                 ret = btrfs_drop_extents(trans, root, inode,
3534                                          last_dest_end, destoff + len, 1);
3535                 if (ret) {
3536                         if (ret != -EOPNOTSUPP)
3537                                 btrfs_abort_transaction(trans, root, ret);
3538                         btrfs_end_transaction(trans, root);
3539                         goto out;
3540                 }
3541                 clone_update_extent_map(inode, trans, NULL, last_dest_end,
3542                                         destoff + len - last_dest_end);
3543                 ret = clone_finish_inode_update(trans, inode, destoff + len,
3544                                                 destoff, olen);
3545         }
3546
3547 out:
3548         btrfs_free_path(path);
3549         vfree(buf);
3550         return ret;
3551 }
3552
3553 static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
3554                                        u64 off, u64 olen, u64 destoff)
3555 {
3556         struct inode *inode = file_inode(file);
3557         struct btrfs_root *root = BTRFS_I(inode)->root;
3558         struct fd src_file;
3559         struct inode *src;
3560         int ret;
3561         u64 len = olen;
3562         u64 bs = root->fs_info->sb->s_blocksize;
3563         int same_inode = 0;
3564
3565         /*
3566          * TODO:
3567          * - split compressed inline extents.  annoying: we need to
3568          *   decompress into destination's address_space (the file offset
3569          *   may change, so source mapping won't do), then recompress (or
3570          *   otherwise reinsert) a subrange.
3571          *
3572          * - split destination inode's inline extents.  The inline extents can
3573          *   be either compressed or non-compressed.
3574          */
3575
3576         /* the destination must be opened for writing */
3577         if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
3578                 return -EINVAL;
3579
3580         if (btrfs_root_readonly(root))
3581                 return -EROFS;
3582
3583         ret = mnt_want_write_file(file);
3584         if (ret)
3585                 return ret;
3586
3587         src_file = fdget(srcfd);
3588         if (!src_file.file) {
3589                 ret = -EBADF;
3590                 goto out_drop_write;
3591         }
3592
3593         ret = -EXDEV;
3594         if (src_file.file->f_path.mnt != file->f_path.mnt)
3595                 goto out_fput;
3596
3597         src = file_inode(src_file.file);
3598
3599         ret = -EINVAL;
3600         if (src == inode)
3601                 same_inode = 1;
3602
3603         /* the src must be open for reading */
3604         if (!(src_file.file->f_mode & FMODE_READ))
3605                 goto out_fput;
3606
3607         /* don't make the dst file partly checksummed */
3608         if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
3609             (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
3610                 goto out_fput;
3611
3612         ret = -EISDIR;
3613         if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
3614                 goto out_fput;
3615
3616         ret = -EXDEV;
3617         if (src->i_sb != inode->i_sb)
3618                 goto out_fput;
3619
3620         if (!same_inode) {
3621                 if (inode < src) {
3622                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
3623                         mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
3624                 } else {
3625                         mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
3626                         mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
3627                 }
3628         } else {
3629                 mutex_lock(&src->i_mutex);
3630         }
3631
3632         /* determine range to clone */
3633         ret = -EINVAL;
3634         if (off + len > src->i_size || off + len < off)
3635                 goto out_unlock;
3636         if (len == 0)
3637                 olen = len = src->i_size - off;
3638         /* if we extend to eof, continue to block boundary */
3639         if (off + len == src->i_size)
3640                 len = ALIGN(src->i_size, bs) - off;
3641
3642         if (len == 0) {
3643                 ret = 0;
3644                 goto out_unlock;
3645         }
3646
3647         /* verify the end result is block aligned */
3648         if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
3649             !IS_ALIGNED(destoff, bs))
3650                 goto out_unlock;
3651
3652         /* verify if ranges are overlapped within the same file */
3653         if (same_inode) {
3654                 if (destoff + len > off && destoff < off + len)
3655                         goto out_unlock;
3656         }
3657
3658         if (destoff > inode->i_size) {
3659                 ret = btrfs_cont_expand(inode, inode->i_size, destoff);
3660                 if (ret)
3661                         goto out_unlock;
3662         }
3663
3664         /*
3665          * Lock the target range too. Right after we replace the file extent
3666          * items in the fs tree (which now point to the cloned data), we might
3667          * have a worker replace them with extent items relative to a write
3668          * operation that was issued before this clone operation (i.e. confront
3669          * with inode.c:btrfs_finish_ordered_io).
3670          */
3671         if (same_inode) {
3672                 u64 lock_start = min_t(u64, off, destoff);
3673                 u64 lock_len = max_t(u64, off, destoff) + len - lock_start;
3674
3675                 lock_extent_range(src, lock_start, lock_len);
3676         } else {
3677                 lock_extent_range(src, off, len);
3678                 lock_extent_range(inode, destoff, len);
3679         }
3680
3681         ret = btrfs_clone(src, inode, off, olen, len, destoff);
3682
3683         if (same_inode) {
3684                 u64 lock_start = min_t(u64, off, destoff);
3685                 u64 lock_end = max_t(u64, off, destoff) + len - 1;
3686
3687                 unlock_extent(&BTRFS_I(src)->io_tree, lock_start, lock_end);
3688         } else {
3689                 unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
3690                 unlock_extent(&BTRFS_I(inode)->io_tree, destoff,
3691                               destoff + len - 1);
3692         }
3693         /*
3694          * Truncate page cache pages so that future reads will see the cloned
3695          * data immediately and not the previous data.
3696          */
3697         truncate_inode_pages_range(&inode->i_data, destoff,
3698                                    PAGE_CACHE_ALIGN(destoff + len) - 1);
3699 out_unlock:
3700         if (!same_inode) {
3701                 if (inode < src) {
3702                         mutex_unlock(&src->i_mutex);
3703                         mutex_unlock(&inode->i_mutex);
3704                 } else {
3705                         mutex_unlock(&inode->i_mutex);
3706                         mutex_unlock(&src->i_mutex);
3707                 }
3708         } else {
3709                 mutex_unlock(&src->i_mutex);
3710         }
3711 out_fput:
3712         fdput(src_file);
3713 out_drop_write:
3714         mnt_drop_write_file(file);
3715         return ret;
3716 }
3717
3718 static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3719 {
3720         struct btrfs_ioctl_clone_range_args args;
3721
3722         if (copy_from_user(&args, argp, sizeof(args)))
3723                 return -EFAULT;
3724         return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
3725                                  args.src_length, args.dest_offset);
3726 }
3727
3728 /*
3729  * there are many ways the trans_start and trans_end ioctls can lead
3730  * to deadlocks.  They should only be used by applications that
3731  * basically own the machine, and have a very in depth understanding
3732  * of all the possible deadlocks and enospc problems.
3733  */
3734 static long btrfs_ioctl_trans_start(struct file *file)
3735 {
3736         struct inode *inode = file_inode(file);
3737         struct btrfs_root *root = BTRFS_I(inode)->root;
3738         struct btrfs_trans_handle *trans;
3739         int ret;
3740
3741         ret = -EPERM;
3742         if (!capable(CAP_SYS_ADMIN))
3743                 goto out;
3744
3745         ret = -EINPROGRESS;
3746         if (file->private_data)
3747                 goto out;
3748
3749         ret = -EROFS;
3750         if (btrfs_root_readonly(root))
3751                 goto out;
3752
3753         ret = mnt_want_write_file(file);
3754         if (ret)
3755                 goto out;
3756
3757         atomic_inc(&root->fs_info->open_ioctl_trans);
3758
3759         ret = -ENOMEM;
3760         trans = btrfs_start_ioctl_transaction(root);
3761         if (IS_ERR(trans))
3762                 goto out_drop;
3763
3764         file->private_data = trans;
3765         return 0;
3766
3767 out_drop:
3768         atomic_dec(&root->fs_info->open_ioctl_trans);
3769         mnt_drop_write_file(file);
3770 out:
3771         return ret;
3772 }
3773
3774 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3775 {
3776         struct inode *inode = file_inode(file);
3777         struct btrfs_root *root = BTRFS_I(inode)->root;
3778         struct btrfs_root *new_root;
3779         struct btrfs_dir_item *di;
3780         struct btrfs_trans_handle *trans;
3781         struct btrfs_path *path;
3782         struct btrfs_key location;
3783         struct btrfs_disk_key disk_key;
3784         u64 objectid = 0;
3785         u64 dir_id;
3786         int ret;
3787
3788         if (!capable(CAP_SYS_ADMIN))
3789                 return -EPERM;
3790
3791         ret = mnt_want_write_file(file);
3792         if (ret)
3793                 return ret;
3794
3795         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3796                 ret = -EFAULT;
3797                 goto out;
3798         }
3799
3800         if (!objectid)
3801                 objectid = BTRFS_FS_TREE_OBJECTID;
3802
3803         location.objectid = objectid;
3804         location.type = BTRFS_ROOT_ITEM_KEY;
3805         location.offset = (u64)-1;
3806
3807         new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3808         if (IS_ERR(new_root)) {
3809                 ret = PTR_ERR(new_root);
3810                 goto out;
3811         }
3812
3813         path = btrfs_alloc_path();
3814         if (!path) {
3815                 ret = -ENOMEM;
3816                 goto out;
3817         }
3818         path->leave_spinning = 1;
3819
3820         trans = btrfs_start_transaction(root, 1);
3821         if (IS_ERR(trans)) {
3822                 btrfs_free_path(path);
3823                 ret = PTR_ERR(trans);
3824                 goto out;
3825         }
3826
3827         dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3828         di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
3829                                    dir_id, "default", 7, 1);
3830         if (IS_ERR_OR_NULL(di)) {
3831                 btrfs_free_path(path);
3832                 btrfs_end_transaction(trans, root);
3833                 btrfs_err(new_root->fs_info, "Umm, you don't have the default dir"
3834                            "item, this isn't going to work");
3835                 ret = -ENOENT;
3836                 goto out;
3837         }
3838
3839         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3840         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3841         btrfs_mark_buffer_dirty(path->nodes[0]);
3842         btrfs_free_path(path);
3843
3844         btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3845         btrfs_end_transaction(trans, root);
3846 out:
3847         mnt_drop_write_file(file);
3848         return ret;
3849 }
3850
3851 void btrfs_get_block_group_info(struct list_head *groups_list,
3852                                 struct btrfs_ioctl_space_info *space)
3853 {
3854         struct btrfs_block_group_cache *block_group;
3855
3856         space->total_bytes = 0;
3857         space->used_bytes = 0;
3858         space->flags = 0;
3859         list_for_each_entry(block_group, groups_list, list) {
3860                 space->flags = block_group->flags;
3861                 space->total_bytes += block_group->key.offset;
3862                 space->used_bytes +=
3863                         btrfs_block_group_used(&block_group->item);
3864         }
3865 }
3866
3867 static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
3868 {
3869         struct btrfs_ioctl_space_args space_args;
3870         struct btrfs_ioctl_space_info space;
3871         struct btrfs_ioctl_space_info *dest;
3872         struct btrfs_ioctl_space_info *dest_orig;
3873         struct btrfs_ioctl_space_info __user *user_dest;
3874         struct btrfs_space_info *info;
3875         u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
3876                        BTRFS_BLOCK_GROUP_SYSTEM,
3877                        BTRFS_BLOCK_GROUP_METADATA,
3878                        BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
3879         int num_types = 4;
3880         int alloc_size;
3881         int ret = 0;
3882         u64 slot_count = 0;
3883         int i, c;
3884
3885         if (copy_from_user(&space_args,
3886                            (struct btrfs_ioctl_space_args __user *)arg,
3887                            sizeof(space_args)))
3888                 return -EFAULT;
3889
3890         for (i = 0; i < num_types; i++) {
3891                 struct btrfs_space_info *tmp;
3892
3893                 info = NULL;
3894                 rcu_read_lock();
3895                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3896                                         list) {
3897                         if (tmp->flags == types[i]) {
3898                                 info = tmp;
3899                                 break;
3900                         }
3901                 }
3902                 rcu_read_unlock();
3903
3904                 if (!info)
3905                         continue;
3906
3907                 down_read(&info->groups_sem);
3908                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3909                         if (!list_empty(&info->block_groups[c]))
3910                                 slot_count++;
3911                 }
3912                 up_read(&info->groups_sem);
3913         }
3914
3915         /*
3916          * Global block reserve, exported as a space_info
3917          */
3918         slot_count++;
3919
3920         /* space_slots == 0 means they are asking for a count */
3921         if (space_args.space_slots == 0) {
3922                 space_args.total_spaces = slot_count;
3923                 goto out;
3924         }
3925
3926         slot_count = min_t(u64, space_args.space_slots, slot_count);
3927
3928         alloc_size = sizeof(*dest) * slot_count;
3929
3930         /* we generally have at most 6 or so space infos, one for each raid
3931          * level.  So, a whole page should be more than enough for everyone
3932          */
3933         if (alloc_size > PAGE_CACHE_SIZE)
3934                 return -ENOMEM;
3935
3936         space_args.total_spaces = 0;
3937         dest = kmalloc(alloc_size, GFP_NOFS);
3938         if (!dest)
3939                 return -ENOMEM;
3940         dest_orig = dest;
3941
3942         /* now we have a buffer to copy into */
3943         for (i = 0; i < num_types; i++) {
3944                 struct btrfs_space_info *tmp;
3945
3946                 if (!slot_count)
3947                         break;
3948
3949                 info = NULL;
3950                 rcu_read_lock();
3951                 list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
3952                                         list) {
3953                         if (tmp->flags == types[i]) {
3954                                 info = tmp;
3955                                 break;
3956                         }
3957                 }
3958                 rcu_read_unlock();
3959
3960                 if (!info)
3961                         continue;
3962                 down_read(&info->groups_sem);
3963                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3964                         if (!list_empty(&info->block_groups[c])) {
3965                                 btrfs_get_block_group_info(
3966                                         &info->block_groups[c], &space);
3967                                 memcpy(dest, &space, sizeof(space));
3968                                 dest++;
3969                                 space_args.total_spaces++;
3970                                 slot_count--;
3971                         }
3972                         if (!slot_count)
3973                                 break;
3974                 }
3975                 up_read(&info->groups_sem);
3976         }
3977
3978         /*
3979          * Add global block reserve
3980          */
3981         if (slot_count) {
3982                 struct btrfs_block_rsv *block_rsv = &root->fs_info->global_block_rsv;
3983
3984                 spin_lock(&block_rsv->lock);
3985                 space.total_bytes = block_rsv->size;
3986                 space.used_bytes = block_rsv->size - block_rsv->reserved;
3987                 spin_unlock(&block_rsv->lock);
3988                 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3989                 memcpy(dest, &space, sizeof(space));
3990                 space_args.total_spaces++;
3991         }
3992
3993         user_dest = (struct btrfs_ioctl_space_info __user *)
3994                 (arg + sizeof(struct btrfs_ioctl_space_args));
3995
3996         if (copy_to_user(user_dest, dest_orig, alloc_size))
3997                 ret = -EFAULT;
3998
3999         kfree(dest_orig);
4000 out:
4001         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
4002                 ret = -EFAULT;
4003
4004         return ret;
4005 }
4006
4007 /*
4008  * there are many ways the trans_start and trans_end ioctls can lead
4009  * to deadlocks.  They should only be used by applications that
4010  * basically own the machine, and have a very in depth understanding
4011  * of all the possible deadlocks and enospc problems.
4012  */
4013 long btrfs_ioctl_trans_end(struct file *file)
4014 {
4015         struct inode *inode = file_inode(file);
4016         struct btrfs_root *root = BTRFS_I(inode)->root;
4017         struct btrfs_trans_handle *trans;
4018
4019         trans = file->private_data;
4020         if (!trans)
4021                 return -EINVAL;
4022         file->private_data = NULL;
4023
4024         btrfs_end_transaction(trans, root);
4025
4026         atomic_dec(&root->fs_info->open_ioctl_trans);
4027
4028         mnt_drop_write_file(file);
4029         return 0;
4030 }
4031
4032 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
4033                                             void __user *argp)
4034 {
4035         struct btrfs_trans_handle *trans;
4036         u64 transid;
4037         int ret;
4038
4039         trans = btrfs_attach_transaction_barrier(root);
4040         if (IS_ERR(trans)) {
4041                 if (PTR_ERR(trans) != -ENOENT)
4042                         return PTR_ERR(trans);
4043
4044                 /* No running transaction, don't bother */
4045                 transid = root->fs_info->last_trans_committed;
4046                 goto out;
4047         }
4048         transid = trans->transid;
4049         ret = btrfs_commit_transaction_async(trans, root, 0);
4050         if (ret) {
4051                 btrfs_end_transaction(trans, root);
4052                 return ret;
4053         }
4054 out:
4055         if (argp)
4056                 if (copy_to_user(argp, &transid, sizeof(transid)))
4057                         return -EFAULT;
4058         return 0;
4059 }
4060
4061 static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
4062                                            void __user *argp)
4063 {
4064         u64 transid;
4065
4066         if (argp) {
4067                 if (copy_from_user(&transid, argp, sizeof(transid)))
4068                         return -EFAULT;
4069         } else {
4070                 transid = 0;  /* current trans */
4071         }
4072         return btrfs_wait_for_commit(root, transid);
4073 }
4074
4075 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
4076 {
4077         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4078         struct btrfs_ioctl_scrub_args *sa;
4079         int ret;
4080
4081         if (!capable(CAP_SYS_ADMIN))
4082                 return -EPERM;
4083
4084         sa = memdup_user(arg, sizeof(*sa));
4085         if (IS_ERR(sa))
4086                 return PTR_ERR(sa);
4087
4088         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
4089                 ret = mnt_want_write_file(file);
4090                 if (ret)
4091                         goto out;
4092         }
4093
4094         ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
4095                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
4096                               0);
4097
4098         if (copy_to_user(arg, sa, sizeof(*sa)))
4099                 ret = -EFAULT;
4100
4101         if (!(sa->flags & BTRFS_SCRUB_READONLY))
4102                 mnt_drop_write_file(file);
4103 out:
4104         kfree(sa);
4105         return ret;
4106 }
4107
4108 static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
4109 {
4110         if (!capable(CAP_SYS_ADMIN))
4111                 return -EPERM;
4112
4113         return btrfs_scrub_cancel(root->fs_info);
4114 }
4115
4116 static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
4117                                        void __user *arg)
4118 {
4119         struct btrfs_ioctl_scrub_args *sa;
4120         int ret;
4121
4122         if (!capable(CAP_SYS_ADMIN))
4123                 return -EPERM;
4124
4125         sa = memdup_user(arg, sizeof(*sa));
4126         if (IS_ERR(sa))
4127                 return PTR_ERR(sa);
4128
4129         ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
4130
4131         if (copy_to_user(arg, sa, sizeof(*sa)))
4132                 ret = -EFAULT;
4133
4134         kfree(sa);
4135         return ret;
4136 }
4137
4138 static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
4139                                       void __user *arg)
4140 {
4141         struct btrfs_ioctl_get_dev_stats *sa;
4142         int ret;
4143
4144         sa = memdup_user(arg, sizeof(*sa));
4145         if (IS_ERR(sa))
4146                 return PTR_ERR(sa);
4147
4148         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
4149                 kfree(sa);
4150                 return -EPERM;
4151         }
4152
4153         ret = btrfs_get_dev_stats(root, sa);
4154
4155         if (copy_to_user(arg, sa, sizeof(*sa)))
4156                 ret = -EFAULT;
4157
4158         kfree(sa);
4159         return ret;
4160 }
4161
4162 static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
4163 {
4164         struct btrfs_ioctl_dev_replace_args *p;
4165         int ret;
4166
4167         if (!capable(CAP_SYS_ADMIN))
4168                 return -EPERM;
4169
4170         p = memdup_user(arg, sizeof(*p));
4171         if (IS_ERR(p))
4172                 return PTR_ERR(p);
4173
4174         switch (p->cmd) {
4175         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
4176                 if (root->fs_info->sb->s_flags & MS_RDONLY) {
4177                         ret = -EROFS;
4178                         goto out;
4179                 }
4180                 if (atomic_xchg(
4181                         &root->fs_info->mutually_exclusive_operation_running,
4182                         1)) {
4183                         ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4184                 } else {
4185                         ret = btrfs_dev_replace_start(root, p);
4186                         atomic_set(
4187                          &root->fs_info->mutually_exclusive_operation_running,
4188                          0);
4189                 }
4190                 break;
4191         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
4192                 btrfs_dev_replace_status(root->fs_info, p);
4193                 ret = 0;
4194                 break;
4195         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
4196                 ret = btrfs_dev_replace_cancel(root->fs_info, p);
4197                 break;
4198         default:
4199                 ret = -EINVAL;
4200                 break;
4201         }
4202
4203         if (copy_to_user(arg, p, sizeof(*p)))
4204                 ret = -EFAULT;
4205 out:
4206         kfree(p);
4207         return ret;
4208 }
4209
4210 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
4211 {
4212         int ret = 0;
4213         int i;
4214         u64 rel_ptr;
4215         int size;
4216         struct btrfs_ioctl_ino_path_args *ipa = NULL;
4217         struct inode_fs_paths *ipath = NULL;
4218         struct btrfs_path *path;
4219
4220         if (!capable(CAP_DAC_READ_SEARCH))
4221                 return -EPERM;
4222
4223         path = btrfs_alloc_path();
4224         if (!path) {
4225                 ret = -ENOMEM;
4226                 goto out;
4227         }
4228
4229         ipa = memdup_user(arg, sizeof(*ipa));
4230         if (IS_ERR(ipa)) {
4231                 ret = PTR_ERR(ipa);
4232                 ipa = NULL;
4233                 goto out;
4234         }
4235
4236         size = min_t(u32, ipa->size, 4096);
4237         ipath = init_ipath(size, root, path);
4238         if (IS_ERR(ipath)) {
4239                 ret = PTR_ERR(ipath);
4240                 ipath = NULL;
4241                 goto out;
4242         }
4243
4244         ret = paths_from_inode(ipa->inum, ipath);
4245         if (ret < 0)
4246                 goto out;
4247
4248         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
4249                 rel_ptr = ipath->fspath->val[i] -
4250                           (u64)(unsigned long)ipath->fspath->val;
4251                 ipath->fspath->val[i] = rel_ptr;
4252         }
4253
4254         ret = copy_to_user((void *)(unsigned long)ipa->fspath,
4255                            (void *)(unsigned long)ipath->fspath, size);
4256         if (ret) {
4257                 ret = -EFAULT;
4258                 goto out;
4259         }
4260
4261 out:
4262         btrfs_free_path(path);
4263         free_ipath(ipath);
4264         kfree(ipa);
4265
4266         return ret;
4267 }
4268
4269 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
4270 {
4271         struct btrfs_data_container *inodes = ctx;
4272         const size_t c = 3 * sizeof(u64);
4273
4274         if (inodes->bytes_left >= c) {
4275                 inodes->bytes_left -= c;
4276                 inodes->val[inodes->elem_cnt] = inum;
4277                 inodes->val[inodes->elem_cnt + 1] = offset;
4278                 inodes->val[inodes->elem_cnt + 2] = root;
4279                 inodes->elem_cnt += 3;
4280         } else {
4281                 inodes->bytes_missing += c - inodes->bytes_left;
4282                 inodes->bytes_left = 0;
4283                 inodes->elem_missed += 3;
4284         }
4285
4286         return 0;
4287 }
4288
4289 static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
4290                                         void __user *arg)
4291 {
4292         int ret = 0;
4293         int size;
4294         struct btrfs_ioctl_logical_ino_args *loi;
4295         struct btrfs_data_container *inodes = NULL;
4296         struct btrfs_path *path = NULL;
4297
4298         if (!capable(CAP_SYS_ADMIN))
4299                 return -EPERM;
4300
4301         loi = memdup_user(arg, sizeof(*loi));
4302         if (IS_ERR(loi)) {
4303                 ret = PTR_ERR(loi);
4304                 loi = NULL;
4305                 goto out;
4306         }
4307
4308         path = btrfs_alloc_path();
4309         if (!path) {
4310                 ret = -ENOMEM;
4311                 goto out;
4312         }
4313
4314         size = min_t(u32, loi->size, 64 * 1024);
4315         inodes = init_data_container(size);
4316         if (IS_ERR(inodes)) {
4317                 ret = PTR_ERR(inodes);
4318                 inodes = NULL;
4319                 goto out;
4320         }
4321
4322         ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
4323                                           build_ino_list, inodes);
4324         if (ret == -EINVAL)
4325                 ret = -ENOENT;
4326         if (ret < 0)
4327                 goto out;
4328
4329         ret = copy_to_user((void *)(unsigned long)loi->inodes,
4330                            (void *)(unsigned long)inodes, size);
4331         if (ret)
4332                 ret = -EFAULT;
4333
4334 out:
4335         btrfs_free_path(path);
4336         vfree(inodes);
4337         kfree(loi);
4338
4339         return ret;
4340 }
4341
4342 void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
4343                                struct btrfs_ioctl_balance_args *bargs)
4344 {
4345         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4346
4347         bargs->flags = bctl->flags;
4348
4349         if (atomic_read(&fs_info->balance_running))
4350                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4351         if (atomic_read(&fs_info->balance_pause_req))
4352                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4353         if (atomic_read(&fs_info->balance_cancel_req))
4354                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4355
4356         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4357         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4358         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4359
4360         if (lock) {
4361                 spin_lock(&fs_info->balance_lock);
4362                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4363                 spin_unlock(&fs_info->balance_lock);
4364         } else {
4365                 memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4366         }
4367 }
4368
4369 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4370 {
4371         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4372         struct btrfs_fs_info *fs_info = root->fs_info;
4373         struct btrfs_ioctl_balance_args *bargs;
4374         struct btrfs_balance_control *bctl;
4375         bool need_unlock; /* for mut. excl. ops lock */
4376         int ret;
4377
4378         if (!capable(CAP_SYS_ADMIN))
4379                 return -EPERM;
4380
4381         ret = mnt_want_write_file(file);
4382         if (ret)
4383                 return ret;
4384
4385 again:
4386         if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
4387                 mutex_lock(&fs_info->volume_mutex);
4388                 mutex_lock(&fs_info->balance_mutex);
4389                 need_unlock = true;
4390                 goto locked;
4391         }
4392
4393         /*
4394          * mut. excl. ops lock is locked.  Three possibilites:
4395          *   (1) some other op is running
4396          *   (2) balance is running
4397          *   (3) balance is paused -- special case (think resume)
4398          */
4399         mutex_lock(&fs_info->balance_mutex);
4400         if (fs_info->balance_ctl) {
4401                 /* this is either (2) or (3) */
4402                 if (!atomic_read(&fs_info->balance_running)) {
4403                         mutex_unlock(&fs_info->balance_mutex);
4404                         if (!mutex_trylock(&fs_info->volume_mutex))
4405                                 goto again;
4406                         mutex_lock(&fs_info->balance_mutex);
4407
4408                         if (fs_info->balance_ctl &&
4409                             !atomic_read(&fs_info->balance_running)) {
4410                                 /* this is (3) */
4411                                 need_unlock = false;
4412                                 goto locked;
4413                         }
4414
4415                         mutex_unlock(&fs_info->balance_mutex);
4416                         mutex_unlock(&fs_info->volume_mutex);
4417                         goto again;
4418                 } else {
4419                         /* this is (2) */
4420                         mutex_unlock(&fs_info->balance_mutex);
4421                         ret = -EINPROGRESS;
4422                         goto out;
4423                 }
4424         } else {
4425                 /* this is (1) */
4426                 mutex_unlock(&fs_info->balance_mutex);
4427                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4428                 goto out;
4429         }
4430
4431 locked:
4432         BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
4433
4434         if (arg) {
4435                 bargs = memdup_user(arg, sizeof(*bargs));
4436                 if (IS_ERR(bargs)) {
4437                         ret = PTR_ERR(bargs);
4438                         goto out_unlock;
4439                 }
4440
4441                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4442                         if (!fs_info->balance_ctl) {
4443                                 ret = -ENOTCONN;
4444                                 goto out_bargs;
4445                         }
4446
4447                         bctl = fs_info->balance_ctl;
4448                         spin_lock(&fs_info->balance_lock);
4449                         bctl->flags |= BTRFS_BALANCE_RESUME;
4450                         spin_unlock(&fs_info->balance_lock);
4451
4452                         goto do_balance;
4453                 }
4454         } else {
4455                 bargs = NULL;
4456         }
4457
4458         if (fs_info->balance_ctl) {
4459                 ret = -EINPROGRESS;
4460                 goto out_bargs;
4461         }
4462
4463         bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
4464         if (!bctl) {
4465                 ret = -ENOMEM;
4466                 goto out_bargs;
4467         }
4468
4469         bctl->fs_info = fs_info;
4470         if (arg) {
4471                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4472                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4473                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4474
4475                 bctl->flags = bargs->flags;
4476         } else {
4477                 /* balance everything - no filters */
4478                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4479         }
4480
4481 do_balance:
4482         /*
4483          * Ownership of bctl and mutually_exclusive_operation_running
4484          * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
4485          * or, if restriper was paused all the way until unmount, in
4486          * free_fs_info.  mutually_exclusive_operation_running is
4487          * cleared in __cancel_balance.
4488          */
4489         need_unlock = false;
4490
4491         ret = btrfs_balance(bctl, bargs);
4492
4493         if (arg) {
4494                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4495                         ret = -EFAULT;
4496         }
4497
4498 out_bargs:
4499         kfree(bargs);
4500 out_unlock:
4501         mutex_unlock(&fs_info->balance_mutex);
4502         mutex_unlock(&fs_info->volume_mutex);
4503         if (need_unlock)
4504                 atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
4505 out:
4506         mnt_drop_write_file(file);
4507         return ret;
4508 }
4509
4510 static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
4511 {
4512         if (!capable(CAP_SYS_ADMIN))
4513                 return -EPERM;
4514
4515         switch (cmd) {
4516         case BTRFS_BALANCE_CTL_PAUSE:
4517                 return btrfs_pause_balance(root->fs_info);
4518         case BTRFS_BALANCE_CTL_CANCEL:
4519                 return btrfs_cancel_balance(root->fs_info);
4520         }
4521
4522         return -EINVAL;
4523 }
4524
4525 static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
4526                                          void __user *arg)
4527 {
4528         struct btrfs_fs_info *fs_info = root->fs_info;
4529         struct btrfs_ioctl_balance_args *bargs;
4530         int ret = 0;
4531
4532         if (!capable(CAP_SYS_ADMIN))
4533                 return -EPERM;
4534
4535         mutex_lock(&fs_info->balance_mutex);
4536         if (!fs_info->balance_ctl) {
4537                 ret = -ENOTCONN;
4538                 goto out;
4539         }
4540
4541         bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
4542         if (!bargs) {
4543                 ret = -ENOMEM;
4544                 goto out;
4545         }
4546
4547         update_ioctl_balance_args(fs_info, 1, bargs);
4548
4549         if (copy_to_user(arg, bargs, sizeof(*bargs)))
4550                 ret = -EFAULT;
4551
4552         kfree(bargs);
4553 out:
4554         mutex_unlock(&fs_info->balance_mutex);
4555         return ret;
4556 }
4557
4558 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4559 {
4560         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4561         struct btrfs_ioctl_quota_ctl_args *sa;
4562         struct btrfs_trans_handle *trans = NULL;
4563         int ret;
4564         int err;
4565
4566         if (!capable(CAP_SYS_ADMIN))
4567                 return -EPERM;
4568
4569         ret = mnt_want_write_file(file);
4570         if (ret)
4571                 return ret;
4572
4573         sa = memdup_user(arg, sizeof(*sa));
4574         if (IS_ERR(sa)) {
4575                 ret = PTR_ERR(sa);
4576                 goto drop_write;
4577         }
4578
4579         down_write(&root->fs_info->subvol_sem);
4580         trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
4581         if (IS_ERR(trans)) {
4582                 ret = PTR_ERR(trans);
4583                 goto out;
4584         }
4585
4586         switch (sa->cmd) {
4587         case BTRFS_QUOTA_CTL_ENABLE:
4588                 ret = btrfs_quota_enable(trans, root->fs_info);
4589                 break;
4590         case BTRFS_QUOTA_CTL_DISABLE:
4591                 ret = btrfs_quota_disable(trans, root->fs_info);
4592                 break;
4593         default:
4594                 ret = -EINVAL;
4595                 break;
4596         }
4597
4598         err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
4599         if (err && !ret)
4600                 ret = err;
4601 out:
4602         kfree(sa);
4603         up_write(&root->fs_info->subvol_sem);
4604 drop_write:
4605         mnt_drop_write_file(file);
4606         return ret;
4607 }
4608
4609 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4610 {
4611         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4612         struct btrfs_ioctl_qgroup_assign_args *sa;
4613         struct btrfs_trans_handle *trans;
4614         int ret;
4615         int err;
4616
4617         if (!capable(CAP_SYS_ADMIN))
4618                 return -EPERM;
4619
4620         ret = mnt_want_write_file(file);
4621         if (ret)
4622                 return ret;
4623
4624         sa = memdup_user(arg, sizeof(*sa));
4625         if (IS_ERR(sa)) {
4626                 ret = PTR_ERR(sa);
4627                 goto drop_write;
4628         }
4629
4630         trans = btrfs_join_transaction(root);
4631         if (IS_ERR(trans)) {
4632                 ret = PTR_ERR(trans);
4633                 goto out;
4634         }
4635
4636         /* FIXME: check if the IDs really exist */
4637         if (sa->assign) {
4638                 ret = btrfs_add_qgroup_relation(trans, root->fs_info,
4639                                                 sa->src, sa->dst);
4640         } else {
4641                 ret = btrfs_del_qgroup_relation(trans, root->fs_info,
4642                                                 sa->src, sa->dst);
4643         }
4644
4645         /* update qgroup status and info */
4646         err = btrfs_run_qgroups(trans, root->fs_info);
4647         if (err < 0)
4648                 btrfs_error(root->fs_info, ret,
4649                             "failed to update qgroup status and info\n");
4650         err = btrfs_end_transaction(trans, root);
4651         if (err && !ret)
4652                 ret = err;
4653
4654 out:
4655         kfree(sa);
4656 drop_write:
4657         mnt_drop_write_file(file);
4658         return ret;
4659 }
4660
4661 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4662 {
4663         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4664         struct btrfs_ioctl_qgroup_create_args *sa;
4665         struct btrfs_trans_handle *trans;
4666         int ret;
4667         int err;
4668
4669         if (!capable(CAP_SYS_ADMIN))
4670                 return -EPERM;
4671
4672         ret = mnt_want_write_file(file);
4673         if (ret)
4674                 return ret;
4675
4676         sa = memdup_user(arg, sizeof(*sa));
4677         if (IS_ERR(sa)) {
4678                 ret = PTR_ERR(sa);
4679                 goto drop_write;
4680         }
4681
4682         if (!sa->qgroupid) {
4683                 ret = -EINVAL;
4684                 goto out;
4685         }
4686
4687         trans = btrfs_join_transaction(root);
4688         if (IS_ERR(trans)) {
4689                 ret = PTR_ERR(trans);
4690                 goto out;
4691         }
4692
4693         /* FIXME: check if the IDs really exist */
4694         if (sa->create) {
4695                 ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid);
4696         } else {
4697                 ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
4698         }
4699
4700         err = btrfs_end_transaction(trans, root);
4701         if (err && !ret)
4702                 ret = err;
4703
4704 out:
4705         kfree(sa);
4706 drop_write:
4707         mnt_drop_write_file(file);
4708         return ret;
4709 }
4710
4711 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4712 {
4713         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4714         struct btrfs_ioctl_qgroup_limit_args *sa;
4715         struct btrfs_trans_handle *trans;
4716         int ret;
4717         int err;
4718         u64 qgroupid;
4719
4720         if (!capable(CAP_SYS_ADMIN))
4721                 return -EPERM;
4722
4723         ret = mnt_want_write_file(file);
4724         if (ret)
4725                 return ret;
4726
4727         sa = memdup_user(arg, sizeof(*sa));
4728         if (IS_ERR(sa)) {
4729                 ret = PTR_ERR(sa);
4730                 goto drop_write;
4731         }
4732
4733         trans = btrfs_join_transaction(root);
4734         if (IS_ERR(trans)) {
4735                 ret = PTR_ERR(trans);
4736                 goto out;
4737         }
4738
4739         qgroupid = sa->qgroupid;
4740         if (!qgroupid) {
4741                 /* take the current subvol as qgroup */
4742                 qgroupid = root->root_key.objectid;
4743         }
4744
4745         /* FIXME: check if the IDs really exist */
4746         ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);
4747
4748         err = btrfs_end_transaction(trans, root);
4749         if (err && !ret)
4750                 ret = err;
4751
4752 out:
4753         kfree(sa);
4754 drop_write:
4755         mnt_drop_write_file(file);
4756         return ret;
4757 }
4758
4759 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4760 {
4761         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4762         struct btrfs_ioctl_quota_rescan_args *qsa;
4763         int ret;
4764
4765         if (!capable(CAP_SYS_ADMIN))
4766                 return -EPERM;
4767
4768         ret = mnt_want_write_file(file);
4769         if (ret)
4770                 return ret;
4771
4772         qsa = memdup_user(arg, sizeof(*qsa));
4773         if (IS_ERR(qsa)) {
4774                 ret = PTR_ERR(qsa);
4775                 goto drop_write;
4776         }
4777
4778         if (qsa->flags) {
4779                 ret = -EINVAL;
4780                 goto out;
4781         }
4782
4783         ret = btrfs_qgroup_rescan(root->fs_info);
4784
4785 out:
4786         kfree(qsa);
4787 drop_write:
4788         mnt_drop_write_file(file);
4789         return ret;
4790 }
4791
4792 static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
4793 {
4794         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4795         struct btrfs_ioctl_quota_rescan_args *qsa;
4796         int ret = 0;
4797
4798         if (!capable(CAP_SYS_ADMIN))
4799                 return -EPERM;
4800
4801         qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
4802         if (!qsa)
4803                 return -ENOMEM;
4804
4805         if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4806                 qsa->flags = 1;
4807                 qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
4808         }
4809
4810         if (copy_to_user(arg, qsa, sizeof(*qsa)))
4811                 ret = -EFAULT;
4812
4813         kfree(qsa);
4814         return ret;
4815 }
4816
4817 static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
4818 {
4819         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4820
4821         if (!capable(CAP_SYS_ADMIN))
4822                 return -EPERM;
4823
4824         return btrfs_qgroup_wait_for_completion(root->fs_info);
4825 }
4826
4827 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4828                                             struct btrfs_ioctl_received_subvol_args *sa)
4829 {
4830         struct inode *inode = file_inode(file);
4831         struct btrfs_root *root = BTRFS_I(inode)->root;
4832         struct btrfs_root_item *root_item = &root->root_item;
4833         struct btrfs_trans_handle *trans;
4834         struct timespec ct = CURRENT_TIME;
4835         int ret = 0;
4836         int received_uuid_changed;
4837
4838         if (!inode_owner_or_capable(inode))
4839                 return -EPERM;
4840
4841         ret = mnt_want_write_file(file);
4842         if (ret < 0)
4843                 return ret;
4844
4845         down_write(&root->fs_info->subvol_sem);
4846
4847         if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
4848                 ret = -EINVAL;
4849                 goto out;
4850         }
4851
4852         if (btrfs_root_readonly(root)) {
4853                 ret = -EROFS;
4854                 goto out;
4855         }
4856
4857         /*
4858          * 1 - root item
4859          * 2 - uuid items (received uuid + subvol uuid)
4860          */
4861         trans = btrfs_start_transaction(root, 3);
4862         if (IS_ERR(trans)) {
4863                 ret = PTR_ERR(trans);
4864                 trans = NULL;
4865                 goto out;
4866         }
4867
4868         sa->rtransid = trans->transid;
4869         sa->rtime.sec = ct.tv_sec;
4870         sa->rtime.nsec = ct.tv_nsec;
4871
4872         received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4873                                        BTRFS_UUID_SIZE);
4874         if (received_uuid_changed &&
4875             !btrfs_is_empty_uuid(root_item->received_uuid))
4876                 btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
4877                                     root_item->received_uuid,
4878                                     BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4879                                     root->root_key.objectid);
4880         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4881         btrfs_set_root_stransid(root_item, sa->stransid);
4882         btrfs_set_root_rtransid(root_item, sa->rtransid);
4883         btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4884         btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4885         btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4886         btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4887
4888         ret = btrfs_update_root(trans, root->fs_info->tree_root,
4889                                 &root->root_key, &root->root_item);
4890         if (ret < 0) {
4891                 btrfs_end_transaction(trans, root);
4892                 goto out;
4893         }
4894         if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4895                 ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
4896                                           sa->uuid,
4897                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4898                                           root->root_key.objectid);
4899                 if (ret < 0 && ret != -EEXIST) {
4900                         btrfs_abort_transaction(trans, root, ret);
4901                         goto out;
4902                 }
4903         }
4904         ret = btrfs_commit_transaction(trans, root);
4905         if (ret < 0) {
4906                 btrfs_abort_transaction(trans, root, ret);
4907                 goto out;
4908         }
4909
4910 out:
4911         up_write(&root->fs_info->subvol_sem);
4912         mnt_drop_write_file(file);
4913         return ret;
4914 }
4915
4916 #ifdef CONFIG_64BIT
4917 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4918                                                 void __user *arg)
4919 {
4920         struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4921         struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4922         int ret = 0;
4923
4924         args32 = memdup_user(arg, sizeof(*args32));
4925         if (IS_ERR(args32)) {
4926                 ret = PTR_ERR(args32);
4927                 args32 = NULL;
4928                 goto out;
4929         }
4930
4931         args64 = kmalloc(sizeof(*args64), GFP_NOFS);
4932         if (!args64) {
4933                 ret = -ENOMEM;
4934                 goto out;
4935         }
4936
4937         memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4938         args64->stransid = args32->stransid;
4939         args64->rtransid = args32->rtransid;
4940         args64->stime.sec = args32->stime.sec;
4941         args64->stime.nsec = args32->stime.nsec;
4942         args64->rtime.sec = args32->rtime.sec;
4943         args64->rtime.nsec = args32->rtime.nsec;
4944         args64->flags = args32->flags;
4945
4946         ret = _btrfs_ioctl_set_received_subvol(file, args64);
4947         if (ret)
4948                 goto out;
4949
4950         memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4951         args32->stransid = args64->stransid;
4952         args32->rtransid = args64->rtransid;
4953         args32->stime.sec = args64->stime.sec;
4954         args32->stime.nsec = args64->stime.nsec;
4955         args32->rtime.sec = args64->rtime.sec;
4956         args32->rtime.nsec = args64->rtime.nsec;
4957         args32->flags = args64->flags;
4958
4959         ret = copy_to_user(arg, args32, sizeof(*args32));
4960         if (ret)
4961                 ret = -EFAULT;
4962
4963 out:
4964         kfree(args32);
4965         kfree(args64);
4966         return ret;
4967 }
4968 #endif
4969
4970 static long btrfs_ioctl_set_received_subvol(struct file *file,
4971                                             void __user *arg)
4972 {
4973         struct btrfs_ioctl_received_subvol_args *sa = NULL;
4974         int ret = 0;
4975
4976         sa = memdup_user(arg, sizeof(*sa));
4977         if (IS_ERR(sa)) {
4978                 ret = PTR_ERR(sa);
4979                 sa = NULL;
4980                 goto out;
4981         }
4982
4983         ret = _btrfs_ioctl_set_received_subvol(file, sa);
4984
4985         if (ret)
4986                 goto out;
4987
4988         ret = copy_to_user(arg, sa, sizeof(*sa));
4989         if (ret)
4990                 ret = -EFAULT;
4991
4992 out:
4993         kfree(sa);
4994         return ret;
4995 }
4996
4997 static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
4998 {
4999         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5000         size_t len;
5001         int ret;
5002         char label[BTRFS_LABEL_SIZE];
5003
5004         spin_lock(&root->fs_info->super_lock);
5005         memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
5006         spin_unlock(&root->fs_info->super_lock);
5007
5008         len = strnlen(label, BTRFS_LABEL_SIZE);
5009
5010         if (len == BTRFS_LABEL_SIZE) {
5011                 btrfs_warn(root->fs_info,
5012                         "label is too long, return the first %zu bytes", --len);
5013         }
5014
5015         ret = copy_to_user(arg, label, len);
5016
5017         return ret ? -EFAULT : 0;
5018 }
5019
5020 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
5021 {
5022         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5023         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5024         struct btrfs_trans_handle *trans;
5025         char label[BTRFS_LABEL_SIZE];
5026         int ret;
5027
5028         if (!capable(CAP_SYS_ADMIN))
5029                 return -EPERM;
5030
5031         if (copy_from_user(label, arg, sizeof(label)))
5032                 return -EFAULT;
5033
5034         if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
5035                 btrfs_err(root->fs_info, "unable to set label with more than %d bytes",
5036                        BTRFS_LABEL_SIZE - 1);
5037                 return -EINVAL;
5038         }
5039
5040         ret = mnt_want_write_file(file);
5041         if (ret)
5042                 return ret;
5043
5044         trans = btrfs_start_transaction(root, 0);
5045         if (IS_ERR(trans)) {
5046                 ret = PTR_ERR(trans);
5047                 goto out_unlock;
5048         }
5049
5050         spin_lock(&root->fs_info->super_lock);
5051         strcpy(super_block->label, label);
5052         spin_unlock(&root->fs_info->super_lock);
5053         ret = btrfs_commit_transaction(trans, root);
5054
5055 out_unlock:
5056         mnt_drop_write_file(file);
5057         return ret;
5058 }
5059
5060 #define INIT_FEATURE_FLAGS(suffix) \
5061         { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
5062           .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
5063           .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
5064
5065 static int btrfs_ioctl_get_supported_features(struct file *file,
5066                                               void __user *arg)
5067 {
5068         static struct btrfs_ioctl_feature_flags features[3] = {
5069                 INIT_FEATURE_FLAGS(SUPP),
5070                 INIT_FEATURE_FLAGS(SAFE_SET),
5071                 INIT_FEATURE_FLAGS(SAFE_CLEAR)
5072         };
5073
5074         if (copy_to_user(arg, &features, sizeof(features)))
5075                 return -EFAULT;
5076
5077         return 0;
5078 }
5079
5080 static int btrfs_ioctl_get_features(struct file *file, void __user *arg)
5081 {
5082         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5083         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5084         struct btrfs_ioctl_feature_flags features;
5085
5086         features.compat_flags = btrfs_super_compat_flags(super_block);
5087         features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
5088         features.incompat_flags = btrfs_super_incompat_flags(super_block);
5089
5090         if (copy_to_user(arg, &features, sizeof(features)))
5091                 return -EFAULT;
5092
5093         return 0;
5094 }
5095
5096 static int check_feature_bits(struct btrfs_root *root,
5097                               enum btrfs_feature_set set,
5098                               u64 change_mask, u64 flags, u64 supported_flags,
5099                               u64 safe_set, u64 safe_clear)
5100 {
5101         const char *type = btrfs_feature_set_names[set];
5102         char *names;
5103         u64 disallowed, unsupported;
5104         u64 set_mask = flags & change_mask;
5105         u64 clear_mask = ~flags & change_mask;
5106
5107         unsupported = set_mask & ~supported_flags;
5108         if (unsupported) {
5109                 names = btrfs_printable_features(set, unsupported);
5110                 if (names) {
5111                         btrfs_warn(root->fs_info,
5112                            "this kernel does not support the %s feature bit%s",
5113                            names, strchr(names, ',') ? "s" : "");
5114                         kfree(names);
5115                 } else
5116                         btrfs_warn(root->fs_info,
5117                            "this kernel does not support %s bits 0x%llx",
5118                            type, unsupported);
5119                 return -EOPNOTSUPP;
5120         }
5121
5122         disallowed = set_mask & ~safe_set;
5123         if (disallowed) {
5124                 names = btrfs_printable_features(set, disallowed);
5125                 if (names) {
5126                         btrfs_warn(root->fs_info,
5127                            "can't set the %s feature bit%s while mounted",
5128                            names, strchr(names, ',') ? "s" : "");
5129                         kfree(names);
5130                 } else
5131                         btrfs_warn(root->fs_info,
5132                            "can't set %s bits 0x%llx while mounted",
5133                            type, disallowed);
5134                 return -EPERM;
5135         }
5136
5137         disallowed = clear_mask & ~safe_clear;
5138         if (disallowed) {
5139                 names = btrfs_printable_features(set, disallowed);
5140                 if (names) {
5141                         btrfs_warn(root->fs_info,
5142                            "can't clear the %s feature bit%s while mounted",
5143                            names, strchr(names, ',') ? "s" : "");
5144                         kfree(names);
5145                 } else
5146                         btrfs_warn(root->fs_info,
5147                            "can't clear %s bits 0x%llx while mounted",
5148                            type, disallowed);
5149                 return -EPERM;
5150         }
5151
5152         return 0;
5153 }
5154
5155 #define check_feature(root, change_mask, flags, mask_base)      \
5156 check_feature_bits(root, FEAT_##mask_base, change_mask, flags,  \
5157                    BTRFS_FEATURE_ ## mask_base ## _SUPP,        \
5158                    BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,    \
5159                    BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
5160
5161 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
5162 {
5163         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5164         struct btrfs_super_block *super_block = root->fs_info->super_copy;
5165         struct btrfs_ioctl_feature_flags flags[2];
5166         struct btrfs_trans_handle *trans;
5167         u64 newflags;
5168         int ret;
5169
5170         if (!capable(CAP_SYS_ADMIN))
5171                 return -EPERM;
5172
5173         if (copy_from_user(flags, arg, sizeof(flags)))
5174                 return -EFAULT;
5175
5176         /* Nothing to do */
5177         if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
5178             !flags[0].incompat_flags)
5179                 return 0;
5180
5181         ret = check_feature(root, flags[0].compat_flags,
5182                             flags[1].compat_flags, COMPAT);
5183         if (ret)
5184                 return ret;
5185
5186         ret = check_feature(root, flags[0].compat_ro_flags,
5187                             flags[1].compat_ro_flags, COMPAT_RO);
5188         if (ret)
5189                 return ret;
5190
5191         ret = check_feature(root, flags[0].incompat_flags,
5192                             flags[1].incompat_flags, INCOMPAT);
5193         if (ret)
5194                 return ret;
5195
5196         trans = btrfs_start_transaction(root, 0);
5197         if (IS_ERR(trans))
5198                 return PTR_ERR(trans);
5199
5200         spin_lock(&root->fs_info->super_lock);
5201         newflags = btrfs_super_compat_flags(super_block);
5202         newflags |= flags[0].compat_flags & flags[1].compat_flags;
5203         newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
5204         btrfs_set_super_compat_flags(super_block, newflags);
5205
5206         newflags = btrfs_super_compat_ro_flags(super_block);
5207         newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
5208         newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
5209         btrfs_set_super_compat_ro_flags(super_block, newflags);
5210
5211         newflags = btrfs_super_incompat_flags(super_block);
5212         newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
5213         newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
5214         btrfs_set_super_incompat_flags(super_block, newflags);
5215         spin_unlock(&root->fs_info->super_lock);
5216
5217         return btrfs_commit_transaction(trans, root);
5218 }
5219
5220 long btrfs_ioctl(struct file *file, unsigned int
5221                 cmd, unsigned long arg)
5222 {
5223         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
5224         void __user *argp = (void __user *)arg;
5225
5226         switch (cmd) {
5227         case FS_IOC_GETFLAGS:
5228                 return btrfs_ioctl_getflags(file, argp);
5229         case FS_IOC_SETFLAGS:
5230                 return btrfs_ioctl_setflags(file, argp);
5231         case FS_IOC_GETVERSION:
5232                 return btrfs_ioctl_getversion(file, argp);
5233         case FITRIM:
5234                 return btrfs_ioctl_fitrim(file, argp);
5235         case BTRFS_IOC_SNAP_CREATE:
5236                 return btrfs_ioctl_snap_create(file, argp, 0);
5237         case BTRFS_IOC_SNAP_CREATE_V2:
5238                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
5239         case BTRFS_IOC_SUBVOL_CREATE:
5240                 return btrfs_ioctl_snap_create(file, argp, 1);
5241         case BTRFS_IOC_SUBVOL_CREATE_V2:
5242                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
5243         case BTRFS_IOC_SNAP_DESTROY:
5244                 return btrfs_ioctl_snap_destroy(file, argp);
5245         case BTRFS_IOC_SUBVOL_GETFLAGS:
5246                 return btrfs_ioctl_subvol_getflags(file, argp);
5247         case BTRFS_IOC_SUBVOL_SETFLAGS:
5248                 return btrfs_ioctl_subvol_setflags(file, argp);
5249         case BTRFS_IOC_DEFAULT_SUBVOL:
5250                 return btrfs_ioctl_default_subvol(file, argp);
5251         case BTRFS_IOC_DEFRAG:
5252                 return btrfs_ioctl_defrag(file, NULL);
5253         case BTRFS_IOC_DEFRAG_RANGE:
5254                 return btrfs_ioctl_defrag(file, argp);
5255         case BTRFS_IOC_RESIZE:
5256                 return btrfs_ioctl_resize(file, argp);
5257         case BTRFS_IOC_ADD_DEV:
5258                 return btrfs_ioctl_add_dev(root, argp);
5259         case BTRFS_IOC_RM_DEV:
5260                 return btrfs_ioctl_rm_dev(file, argp);
5261         case BTRFS_IOC_FS_INFO:
5262                 return btrfs_ioctl_fs_info(root, argp);
5263         case BTRFS_IOC_DEV_INFO:
5264                 return btrfs_ioctl_dev_info(root, argp);
5265         case BTRFS_IOC_BALANCE:
5266                 return btrfs_ioctl_balance(file, NULL);
5267         case BTRFS_IOC_CLONE:
5268                 return btrfs_ioctl_clone(file, arg, 0, 0, 0);
5269         case BTRFS_IOC_CLONE_RANGE:
5270                 return btrfs_ioctl_clone_range(file, argp);
5271         case BTRFS_IOC_TRANS_START:
5272                 return btrfs_ioctl_trans_start(file);
5273         case BTRFS_IOC_TRANS_END:
5274                 return btrfs_ioctl_trans_end(file);
5275         case BTRFS_IOC_TREE_SEARCH:
5276                 return btrfs_ioctl_tree_search(file, argp);
5277         case BTRFS_IOC_TREE_SEARCH_V2:
5278                 return btrfs_ioctl_tree_search_v2(file, argp);
5279         case BTRFS_IOC_INO_LOOKUP:
5280                 return btrfs_ioctl_ino_lookup(file, argp);
5281         case BTRFS_IOC_INO_PATHS:
5282                 return btrfs_ioctl_ino_to_path(root, argp);
5283         case BTRFS_IOC_LOGICAL_INO:
5284                 return btrfs_ioctl_logical_to_ino(root, argp);
5285         case BTRFS_IOC_SPACE_INFO:
5286                 return btrfs_ioctl_space_info(root, argp);
5287         case BTRFS_IOC_SYNC: {
5288                 int ret;
5289
5290                 ret = btrfs_start_delalloc_roots(root->fs_info, 0, -1);
5291                 if (ret)
5292                         return ret;
5293                 ret = btrfs_sync_fs(file_inode(file)->i_sb, 1);
5294                 /*
5295                  * The transaction thread may want to do more work,
5296                  * namely it pokes the cleaner ktread that will start
5297                  * processing uncleaned subvols.
5298                  */
5299                 wake_up_process(root->fs_info->transaction_kthread);
5300                 return ret;
5301         }
5302         case BTRFS_IOC_START_SYNC:
5303                 return btrfs_ioctl_start_sync(root, argp);
5304         case BTRFS_IOC_WAIT_SYNC:
5305                 return btrfs_ioctl_wait_sync(root, argp);
5306         case BTRFS_IOC_SCRUB:
5307                 return btrfs_ioctl_scrub(file, argp);
5308         case BTRFS_IOC_SCRUB_CANCEL:
5309                 return btrfs_ioctl_scrub_cancel(root, argp);
5310         case BTRFS_IOC_SCRUB_PROGRESS:
5311                 return btrfs_ioctl_scrub_progress(root, argp);
5312         case BTRFS_IOC_BALANCE_V2:
5313                 return btrfs_ioctl_balance(file, argp);
5314         case BTRFS_IOC_BALANCE_CTL:
5315                 return btrfs_ioctl_balance_ctl(root, arg);
5316         case BTRFS_IOC_BALANCE_PROGRESS:
5317                 return btrfs_ioctl_balance_progress(root, argp);
5318         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5319                 return btrfs_ioctl_set_received_subvol(file, argp);
5320 #ifdef CONFIG_64BIT
5321         case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5322                 return btrfs_ioctl_set_received_subvol_32(file, argp);
5323 #endif
5324         case BTRFS_IOC_SEND:
5325                 return btrfs_ioctl_send(file, argp);
5326         case BTRFS_IOC_GET_DEV_STATS:
5327                 return btrfs_ioctl_get_dev_stats(root, argp);
5328         case BTRFS_IOC_QUOTA_CTL:
5329                 return btrfs_ioctl_quota_ctl(file, argp);
5330         case BTRFS_IOC_QGROUP_ASSIGN:
5331                 return btrfs_ioctl_qgroup_assign(file, argp);
5332         case BTRFS_IOC_QGROUP_CREATE:
5333                 return btrfs_ioctl_qgroup_create(file, argp);
5334         case BTRFS_IOC_QGROUP_LIMIT:
5335                 return btrfs_ioctl_qgroup_limit(file, argp);
5336         case BTRFS_IOC_QUOTA_RESCAN:
5337                 return btrfs_ioctl_quota_rescan(file, argp);
5338         case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5339                 return btrfs_ioctl_quota_rescan_status(file, argp);
5340         case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5341                 return btrfs_ioctl_quota_rescan_wait(file, argp);
5342         case BTRFS_IOC_DEV_REPLACE:
5343                 return btrfs_ioctl_dev_replace(root, argp);
5344         case BTRFS_IOC_GET_FSLABEL:
5345                 return btrfs_ioctl_get_fslabel(file, argp);
5346         case BTRFS_IOC_SET_FSLABEL:
5347                 return btrfs_ioctl_set_fslabel(file, argp);
5348         case BTRFS_IOC_FILE_EXTENT_SAME:
5349                 return btrfs_ioctl_file_extent_same(file, argp);
5350         case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5351                 return btrfs_ioctl_get_supported_features(file, argp);
5352         case BTRFS_IOC_GET_FEATURES:
5353                 return btrfs_ioctl_get_features(file, argp);
5354         case BTRFS_IOC_SET_FEATURES:
5355                 return btrfs_ioctl_set_features(file, argp);
5356         }
5357
5358         return -ENOTTY;
5359 }