fs/btrfs/ioctl.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2007 Oracle.  All rights reserved.
   4  */
   5
   6 #include <linux/kernel.h>
   7 #include <linux/bio.h>
   8 #include <linux/file.h>
   9 #include <linux/fs.h>
  10 #include <linux/fsnotify.h>
  11 #include <linux/pagemap.h>
  12 #include <linux/highmem.h>
  13 #include <linux/time.h>
  14 #include <linux/string.h>
  15 #include <linux/backing-dev.h>
  16 #include <linux/mount.h>
  17 #include <linux/namei.h>
  18 #include <linux/writeback.h>
  19 #include <linux/compat.h>
  20 #include <linux/security.h>
  21 #include <linux/xattr.h>
  22 #include <linux/mm.h>
  23 #include <linux/slab.h>
  24 #include <linux/blkdev.h>
  25 #include <linux/uuid.h>
  26 #include <linux/btrfs.h>
  27 #include <linux/uaccess.h>
  28 #include <linux/iversion.h>
  29 #include <linux/fileattr.h>
  30 #include <linux/fsverity.h>
  31 #include "ctree.h"
  32 #include "disk-io.h"
  33 #include "export.h"
  34 #include "transaction.h"
  35 #include "btrfs_inode.h"
  36 #include "print-tree.h"
  37 #include "volumes.h"
  38 #include "locking.h"
  39 #include "backref.h"
  40 #include "rcu-string.h"
  41 #include "send.h"
  42 #include "dev-replace.h"
  43 #include "props.h"
  44 #include "sysfs.h"
  45 #include "qgroup.h"
  46 #include "tree-log.h"
  47 #include "compression.h"
  48 #include "space-info.h"
  49 #include "delalloc-space.h"
  50 #include "block-group.h"
  51 #include "subpage.h"
  52
  53 #ifdef CONFIG_64BIT
  54 /* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
  55  * structures are incorrect, as the timespec structure from userspace
  56  * is 4 bytes too small. We define these alternatives here to teach
  57  * the kernel about the 32-bit struct packing.
  58  */
  59 struct btrfs_ioctl_timespec_32 {
  60         __u64 sec;
  61         __u32 nsec;
  62 } __attribute__ ((__packed__));
  63
  64 struct btrfs_ioctl_received_subvol_args_32 {
  65         char    uuid[BTRFS_UUID_SIZE];  /* in */
  66         __u64   stransid;               /* in */
  67         __u64   rtransid;               /* out */
  68         struct btrfs_ioctl_timespec_32 stime; /* in */
  69         struct btrfs_ioctl_timespec_32 rtime; /* out */
  70         __u64   flags;                  /* in */
  71         __u64   reserved[16];           /* in */
  72 } __attribute__ ((__packed__));
  73
  74 #define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
  75                                 struct btrfs_ioctl_received_subvol_args_32)
  76 #endif
  77
  78 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
  79 struct btrfs_ioctl_send_args_32 {
  80         __s64 send_fd;                  /* in */
  81         __u64 clone_sources_count;      /* in */
  82         compat_uptr_t clone_sources;    /* in */
  83         __u64 parent_root;              /* in */
  84         __u64 flags;                    /* in */
  85         __u32 version;                  /* in */
  86         __u8  reserved[28];             /* in */
  87 } __attribute__ ((__packed__));
  88
  89 #define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
  90                                struct btrfs_ioctl_send_args_32)
  91 #endif
  92
  93 /* Mask out flags that are inappropriate for the given type of inode. */
  94 static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
  95                 unsigned int flags)
  96 {
  97         if (S_ISDIR(inode->i_mode))
  98                 return flags;
  99         else if (S_ISREG(inode->i_mode))
 100                 return flags & ~FS_DIRSYNC_FL;
 101         else
 102                 return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
 103 }
 104
 105 /*
 106  * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
 107  * ioctl.
 108  */
 109 static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)
 110 {
 111         unsigned int iflags = 0;
 112         u32 flags = binode->flags;
 113         u32 ro_flags = binode->ro_flags;
 114
 115         if (flags & BTRFS_INODE_SYNC)
 116                 iflags |= FS_SYNC_FL;
 117         if (flags & BTRFS_INODE_IMMUTABLE)
 118                 iflags |= FS_IMMUTABLE_FL;
 119         if (flags & BTRFS_INODE_APPEND)
 120                 iflags |= FS_APPEND_FL;
 121         if (flags & BTRFS_INODE_NODUMP)
 122                 iflags |= FS_NODUMP_FL;
 123         if (flags & BTRFS_INODE_NOATIME)
 124                 iflags |= FS_NOATIME_FL;
 125         if (flags & BTRFS_INODE_DIRSYNC)
 126                 iflags |= FS_DIRSYNC_FL;
 127         if (flags & BTRFS_INODE_NODATACOW)
 128                 iflags |= FS_NOCOW_FL;
 129         if (ro_flags & BTRFS_INODE_RO_VERITY)
 130                 iflags |= FS_VERITY_FL;
 131
 132         if (flags & BTRFS_INODE_NOCOMPRESS)
 133                 iflags |= FS_NOCOMP_FL;
 134         else if (flags & BTRFS_INODE_COMPRESS)
 135                 iflags |= FS_COMPR_FL;
 136
 137         return iflags;
 138 }
 139
 140 /*
 141  * Update inode->i_flags based on the btrfs internal flags.
 142  */
 143 void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
 144 {
 145         struct btrfs_inode *binode = BTRFS_I(inode);
 146         unsigned int new_fl = 0;
 147
 148         if (binode->flags & BTRFS_INODE_SYNC)
 149                 new_fl |= S_SYNC;
 150         if (binode->flags & BTRFS_INODE_IMMUTABLE)
 151                 new_fl |= S_IMMUTABLE;
 152         if (binode->flags & BTRFS_INODE_APPEND)
 153                 new_fl |= S_APPEND;
 154         if (binode->flags & BTRFS_INODE_NOATIME)
 155                 new_fl |= S_NOATIME;
 156         if (binode->flags & BTRFS_INODE_DIRSYNC)
 157                 new_fl |= S_DIRSYNC;
 158         if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
 159                 new_fl |= S_VERITY;
 160
 161         set_mask_bits(&inode->i_flags,
 162                       S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
 163                       S_VERITY, new_fl);
 164 }
 165
 166 /*
 167  * Check if @flags are a supported and valid set of FS_*_FL flags and that
 168  * the old and new flags are not conflicting
 169  */
 170 static int check_fsflags(unsigned int old_flags, unsigned int flags)
 171 {
 172         if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 173                       FS_NOATIME_FL | FS_NODUMP_FL | \
 174                       FS_SYNC_FL | FS_DIRSYNC_FL | \
 175                       FS_NOCOMP_FL | FS_COMPR_FL |
 176                       FS_NOCOW_FL))
 177                 return -EOPNOTSUPP;
 178
 179         /* COMPR and NOCOMP on new/old are valid */
 180         if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 181                 return -EINVAL;
 182
 183         if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
 184                 return -EINVAL;
 185
 186         /* NOCOW and compression options are mutually exclusive */
 187         if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
 188                 return -EINVAL;
 189         if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
 190                 return -EINVAL;
 191
 192         return 0;
 193 }
 194
 195 static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,
 196                                     unsigned int flags)
 197 {
 198         if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))
 199                 return -EPERM;
 200
 201         return 0;
 202 }
 203
 204 /*
 205  * Set flags/xflags from the internal inode flags. The remaining items of
 206  * fsxattr are zeroed.
 207  */
 208 int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
 209 {
 210         struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));
 211
 212         fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));
 213         return 0;
 214 }
 215
 216 int btrfs_fileattr_set(struct user_namespace *mnt_userns,
 217                        struct dentry *dentry, struct fileattr *fa)
 218 {
 219         struct inode *inode = d_inode(dentry);
 220         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 221         struct btrfs_inode *binode = BTRFS_I(inode);
 222         struct btrfs_root *root = binode->root;
 223         struct btrfs_trans_handle *trans;
 224         unsigned int fsflags, old_fsflags;
 225         int ret;
 226         const char *comp = NULL;
 227         u32 binode_flags;
 228
 229         if (btrfs_root_readonly(root))
 230                 return -EROFS;
 231
 232         if (fileattr_has_fsx(fa))
 233                 return -EOPNOTSUPP;
 234
 235         fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);
 236         old_fsflags = btrfs_inode_flags_to_fsflags(binode);
 237         ret = check_fsflags(old_fsflags, fsflags);
 238         if (ret)
 239                 return ret;
 240
 241         ret = check_fsflags_compatible(fs_info, fsflags);
 242         if (ret)
 243                 return ret;
 244
 245         binode_flags = binode->flags;
 246         if (fsflags & FS_SYNC_FL)
 247                 binode_flags |= BTRFS_INODE_SYNC;
 248         else
 249                 binode_flags &= ~BTRFS_INODE_SYNC;
 250         if (fsflags & FS_IMMUTABLE_FL)
 251                 binode_flags |= BTRFS_INODE_IMMUTABLE;
 252         else
 253                 binode_flags &= ~BTRFS_INODE_IMMUTABLE;
 254         if (fsflags & FS_APPEND_FL)
 255                 binode_flags |= BTRFS_INODE_APPEND;
 256         else
 257                 binode_flags &= ~BTRFS_INODE_APPEND;
 258         if (fsflags & FS_NODUMP_FL)
 259                 binode_flags |= BTRFS_INODE_NODUMP;
 260         else
 261                 binode_flags &= ~BTRFS_INODE_NODUMP;
 262         if (fsflags & FS_NOATIME_FL)
 263                 binode_flags |= BTRFS_INODE_NOATIME;
 264         else
 265                 binode_flags &= ~BTRFS_INODE_NOATIME;
 266
 267         /* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */
 268         if (!fa->flags_valid) {
 269                 /* 1 item for the inode */
 270                 trans = btrfs_start_transaction(root, 1);
 271                 if (IS_ERR(trans))
 272                         return PTR_ERR(trans);
 273                 goto update_flags;
 274         }
 275
 276         if (fsflags & FS_DIRSYNC_FL)
 277                 binode_flags |= BTRFS_INODE_DIRSYNC;
 278         else
 279                 binode_flags &= ~BTRFS_INODE_DIRSYNC;
 280         if (fsflags & FS_NOCOW_FL) {
 281                 if (S_ISREG(inode->i_mode)) {
 282                         /*
 283                          * It's safe to turn csums off here, no extents exist.
 284                          * Otherwise we want the flag to reflect the real COW
 285                          * status of the file and will not set it.
 286                          */
 287                         if (inode->i_size == 0)
 288                                 binode_flags |= BTRFS_INODE_NODATACOW |
 289                                                 BTRFS_INODE_NODATASUM;
 290                 } else {
 291                         binode_flags |= BTRFS_INODE_NODATACOW;
 292                 }
 293         } else {
 294                 /*
 295                  * Revert back under same assumptions as above
 296                  */
 297                 if (S_ISREG(inode->i_mode)) {
 298                         if (inode->i_size == 0)
 299                                 binode_flags &= ~(BTRFS_INODE_NODATACOW |
 300                                                   BTRFS_INODE_NODATASUM);
 301                 } else {
 302                         binode_flags &= ~BTRFS_INODE_NODATACOW;
 303                 }
 304         }
 305
 306         /*
 307          * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 308          * flag may be changed automatically if compression code won't make
 309          * things smaller.
 310          */
 311         if (fsflags & FS_NOCOMP_FL) {
 312                 binode_flags &= ~BTRFS_INODE_COMPRESS;
 313                 binode_flags |= BTRFS_INODE_NOCOMPRESS;
 314         } else if (fsflags & FS_COMPR_FL) {
 315
 316                 if (IS_SWAPFILE(inode))
 317                         return -ETXTBSY;
 318
 319                 binode_flags |= BTRFS_INODE_COMPRESS;
 320                 binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
 321
 322                 comp = btrfs_compress_type2str(fs_info->compress_type);
 323                 if (!comp || comp[0] == 0)
 324                         comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
 325         } else {
 326                 binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 327         }
 328
 329         /*
 330          * 1 for inode item
 331          * 2 for properties
 332          */
 333         trans = btrfs_start_transaction(root, 3);
 334         if (IS_ERR(trans))
 335                 return PTR_ERR(trans);
 336
 337         if (comp) {
 338                 ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
 339                                      strlen(comp), 0);
 340                 if (ret) {
 341                         btrfs_abort_transaction(trans, ret);
 342                         goto out_end_trans;
 343                 }
 344         } else {
 345                 ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
 346                                      0, 0);
 347                 if (ret && ret != -ENODATA) {
 348                         btrfs_abort_transaction(trans, ret);
 349                         goto out_end_trans;
 350                 }
 351         }
 352
 353 update_flags:
 354         binode->flags = binode_flags;
 355         btrfs_sync_inode_flags_to_i_flags(inode);
 356         inode_inc_iversion(inode);
 357         inode->i_ctime = current_time(inode);
 358         ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
 359
 360  out_end_trans:
 361         btrfs_end_transaction(trans);
 362         return ret;
 363 }
 364
 365 /*
 366  * Start exclusive operation @type, return true on success
 367  */
 368 bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
 369                         enum btrfs_exclusive_operation type)
 370 {
 371         bool ret = false;
 372
 373         spin_lock(&fs_info->super_lock);
 374         if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {
 375                 fs_info->exclusive_operation = type;
 376                 ret = true;
 377         }
 378         spin_unlock(&fs_info->super_lock);
 379
 380         return ret;
 381 }
 382
 383 /*
 384  * Conditionally allow to enter the exclusive operation in case it's compatible
 385  * with the running one.  This must be paired with btrfs_exclop_start_unlock and
 386  * btrfs_exclop_finish.
 387  *
 388  * Compatibility:
 389  * - the same type is already running
 390  * - when trying to add a device and balance has been paused
 391  * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller
 392  *   must check the condition first that would allow none -> @type
 393  */
 394 bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
 395                                  enum btrfs_exclusive_operation type)
 396 {
 397         spin_lock(&fs_info->super_lock);
 398         if (fs_info->exclusive_operation == type ||
 399             (fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED &&
 400              type == BTRFS_EXCLOP_DEV_ADD))
 401                 return true;
 402
 403         spin_unlock(&fs_info->super_lock);
 404         return false;
 405 }
 406
 407 void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)
 408 {
 409         spin_unlock(&fs_info->super_lock);
 410 }
 411
 412 void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)
 413 {
 414         spin_lock(&fs_info->super_lock);
 415         WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);
 416         spin_unlock(&fs_info->super_lock);
 417         sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");
 418 }
 419
 420 void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
 421                           enum btrfs_exclusive_operation op)
 422 {
 423         switch (op) {
 424         case BTRFS_EXCLOP_BALANCE_PAUSED:
 425                 spin_lock(&fs_info->super_lock);
 426                 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE ||
 427                        fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD);
 428                 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED;
 429                 spin_unlock(&fs_info->super_lock);
 430                 break;
 431         case BTRFS_EXCLOP_BALANCE:
 432                 spin_lock(&fs_info->super_lock);
 433                 ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
 434                 fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
 435                 spin_unlock(&fs_info->super_lock);
 436                 break;
 437         default:
 438                 btrfs_warn(fs_info,
 439                         "invalid exclop balance operation %d requested", op);
 440         }
 441 }
 442
 443 static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 444 {
 445         struct inode *inode = file_inode(file);
 446
 447         return put_user(inode->i_generation, arg);
 448 }
 449
 450 static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
 451                                         void __user *arg)
 452 {
 453         struct btrfs_device *device;
 454         struct request_queue *q;
 455         struct fstrim_range range;
 456         u64 minlen = ULLONG_MAX;
 457         u64 num_devices = 0;
 458         int ret;
 459
 460         if (!capable(CAP_SYS_ADMIN))
 461                 return -EPERM;
 462
 463         /*
 464          * btrfs_trim_block_group() depends on space cache, which is not
 465          * available in zoned filesystem. So, disallow fitrim on a zoned
 466          * filesystem for now.
 467          */
 468         if (btrfs_is_zoned(fs_info))
 469                 return -EOPNOTSUPP;
 470
 471         /*
 472          * If the fs is mounted with nologreplay, which requires it to be
 473          * mounted in RO mode as well, we can not allow discard on free space
 474          * inside block groups, because log trees refer to extents that are not
 475          * pinned in a block group's free space cache (pinning the extents is
 476          * precisely the first phase of replaying a log tree).
 477          */
 478         if (btrfs_test_opt(fs_info, NOLOGREPLAY))
 479                 return -EROFS;
 480
 481         rcu_read_lock();
 482         list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 483                                 dev_list) {
 484                 if (!device->bdev)
 485                         continue;
 486                 q = bdev_get_queue(device->bdev);
 487                 if (blk_queue_discard(q)) {
 488                         num_devices++;
 489                         minlen = min_t(u64, q->limits.discard_granularity,
 490                                      minlen);
 491                 }
 492         }
 493         rcu_read_unlock();
 494
 495         if (!num_devices)
 496                 return -EOPNOTSUPP;
 497         if (copy_from_user(&range, arg, sizeof(range)))
 498                 return -EFAULT;
 499
 500         /*
 501          * NOTE: Don't truncate the range using super->total_bytes.  Bytenr of
 502          * block group is in the logical address space, which can be any
 503          * sectorsize aligned bytenr in  the range [0, U64_MAX].
 504          */
 505         if (range.len < fs_info->sb->s_blocksize)
 506                 return -EINVAL;
 507
 508         range.minlen = max(range.minlen, minlen);
 509         ret = btrfs_trim_fs(fs_info, &range);
 510         if (ret < 0)
 511                 return ret;
 512
 513         if (copy_to_user(arg, &range, sizeof(range)))
 514                 return -EFAULT;
 515
 516         return 0;
 517 }
 518
 519 int __pure btrfs_is_empty_uuid(u8 *uuid)
 520 {
 521         int i;
 522
 523         for (i = 0; i < BTRFS_UUID_SIZE; i++) {
 524                 if (uuid[i])
 525                         return 0;
 526         }
 527         return 1;
 528 }
 529
 530 static noinline int create_subvol(struct user_namespace *mnt_userns,
 531                                   struct inode *dir, struct dentry *dentry,
 532                                   const char *name, int namelen,
 533                                   struct btrfs_qgroup_inherit *inherit)
 534 {
 535         struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 536         struct btrfs_trans_handle *trans;
 537         struct btrfs_key key;
 538         struct btrfs_root_item *root_item;
 539         struct btrfs_inode_item *inode_item;
 540         struct extent_buffer *leaf;
 541         struct btrfs_root *root = BTRFS_I(dir)->root;
 542         struct btrfs_root *new_root;
 543         struct btrfs_block_rsv block_rsv;
 544         struct timespec64 cur_time = current_time(dir);
 545         struct inode *inode;
 546         int ret;
 547         dev_t anon_dev = 0;
 548         u64 objectid;
 549         u64 index = 0;
 550
 551         root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
 552         if (!root_item)
 553                 return -ENOMEM;
 554
 555         ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);
 556         if (ret)
 557                 goto fail_free;
 558
 559         ret = get_anon_bdev(&anon_dev);
 560         if (ret < 0)
 561                 goto fail_free;
 562
 563         /*
 564          * Don't create subvolume whose level is not zero. Or qgroup will be
 565          * screwed up since it assumes subvolume qgroup's level to be 0.
 566          */
 567         if (btrfs_qgroup_level(objectid)) {
 568                 ret = -ENOSPC;
 569                 goto fail_free;
 570         }
 571
 572         btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 573         /*
 574          * The same as the snapshot creation, please see the comment
 575          * of create_snapshot().
 576          */
 577         ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
 578         if (ret)
 579                 goto fail_free;
 580
 581         trans = btrfs_start_transaction(root, 0);
 582         if (IS_ERR(trans)) {
 583                 ret = PTR_ERR(trans);
 584                 btrfs_subvolume_release_metadata(root, &block_rsv);
 585                 goto fail_free;
 586         }
 587         trans->block_rsv = &block_rsv;
 588         trans->bytes_reserved = block_rsv.size;
 589
 590         ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
 591         if (ret)
 592                 goto fail;
 593
 594         leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
 595                                       BTRFS_NESTING_NORMAL);
 596         if (IS_ERR(leaf)) {
 597                 ret = PTR_ERR(leaf);
 598                 goto fail;
 599         }
 600
 601         btrfs_mark_buffer_dirty(leaf);
 602
 603         inode_item = &root_item->inode;
 604         btrfs_set_stack_inode_generation(inode_item, 1);
 605         btrfs_set_stack_inode_size(inode_item, 3);
 606         btrfs_set_stack_inode_nlink(inode_item, 1);
 607         btrfs_set_stack_inode_nbytes(inode_item,
 608                                      fs_info->nodesize);
 609         btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 610
 611         btrfs_set_root_flags(root_item, 0);
 612         btrfs_set_root_limit(root_item, 0);
 613         btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 614
 615         btrfs_set_root_bytenr(root_item, leaf->start);
 616         btrfs_set_root_generation(root_item, trans->transid);
 617         btrfs_set_root_level(root_item, 0);
 618         btrfs_set_root_refs(root_item, 1);
 619         btrfs_set_root_used(root_item, leaf->len);
 620         btrfs_set_root_last_snapshot(root_item, 0);
 621
 622         btrfs_set_root_generation_v2(root_item,
 623                         btrfs_root_generation(root_item));
 624         generate_random_guid(root_item->uuid);
 625         btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
 626         btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
 627         root_item->ctime = root_item->otime;
 628         btrfs_set_root_ctransid(root_item, trans->transid);
 629         btrfs_set_root_otransid(root_item, trans->transid);
 630
 631         btrfs_tree_unlock(leaf);
 632
 633         btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);
 634
 635         key.objectid = objectid;
 636         key.offset = 0;
 637         key.type = BTRFS_ROOT_ITEM_KEY;
 638         ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
 639                                 root_item);
 640         if (ret) {
 641                 /*
 642                  * Since we don't abort the transaction in this case, free the
 643                  * tree block so that we don't leak space and leave the
 644                  * filesystem in an inconsistent state (an extent item in the
 645                  * extent tree with a backreference for a root that does not
 646                  * exists).
 647                  */
 648                 btrfs_tree_lock(leaf);
 649                 btrfs_clean_tree_block(leaf);
 650                 btrfs_tree_unlock(leaf);
 651                 btrfs_free_tree_block(trans, objectid, leaf, 0, 1);
 652                 free_extent_buffer(leaf);
 653                 goto fail;
 654         }
 655
 656         free_extent_buffer(leaf);
 657         leaf = NULL;
 658
 659         key.offset = (u64)-1;
 660         new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
 661         if (IS_ERR(new_root)) {
 662                 free_anon_bdev(anon_dev);
 663                 ret = PTR_ERR(new_root);
 664                 btrfs_abort_transaction(trans, ret);
 665                 goto fail;
 666         }
 667         /* Freeing will be done in btrfs_put_root() of new_root */
 668         anon_dev = 0;
 669
 670         ret = btrfs_record_root_in_trans(trans, new_root);
 671         if (ret) {
 672                 btrfs_put_root(new_root);
 673                 btrfs_abort_transaction(trans, ret);
 674                 goto fail;
 675         }
 676
 677         ret = btrfs_create_subvol_root(trans, new_root, root, mnt_userns);
 678         btrfs_put_root(new_root);
 679         if (ret) {
 680                 /* We potentially lose an unused inode item here */
 681                 btrfs_abort_transaction(trans, ret);
 682                 goto fail;
 683         }
 684
 685         /*
 686          * insert the directory item
 687          */
 688         ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
 689         if (ret) {
 690                 btrfs_abort_transaction(trans, ret);
 691                 goto fail;
 692         }
 693
 694         ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
 695                                     BTRFS_FT_DIR, index);
 696         if (ret) {
 697                 btrfs_abort_transaction(trans, ret);
 698                 goto fail;
 699         }
 700
 701         btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
 702         ret = btrfs_update_inode(trans, root, BTRFS_I(dir));
 703         if (ret) {
 704                 btrfs_abort_transaction(trans, ret);
 705                 goto fail;
 706         }
 707
 708         ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
 709                                  btrfs_ino(BTRFS_I(dir)), index, name, namelen);
 710         if (ret) {
 711                 btrfs_abort_transaction(trans, ret);
 712                 goto fail;
 713         }
 714
 715         ret = btrfs_uuid_tree_add(trans, root_item->uuid,
 716                                   BTRFS_UUID_KEY_SUBVOL, objectid);
 717         if (ret)
 718                 btrfs_abort_transaction(trans, ret);
 719
 720 fail:
 721         kfree(root_item);
 722         trans->block_rsv = NULL;
 723         trans->bytes_reserved = 0;
 724         btrfs_subvolume_release_metadata(root, &block_rsv);
 725
 726         if (ret)
 727                 btrfs_end_transaction(trans);
 728         else
 729                 ret = btrfs_commit_transaction(trans);
 730
 731         if (!ret) {
 732                 inode = btrfs_lookup_dentry(dir, dentry);
 733                 if (IS_ERR(inode))
 734                         return PTR_ERR(inode);
 735                 d_instantiate(dentry, inode);
 736         }
 737         return ret;
 738
 739 fail_free:
 740         if (anon_dev)
 741                 free_anon_bdev(anon_dev);
 742         kfree(root_item);
 743         return ret;
 744 }
 745
 746 static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 747                            struct dentry *dentry, bool readonly,
 748                            struct btrfs_qgroup_inherit *inherit)
 749 {
 750         struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 751         struct inode *inode;
 752         struct btrfs_pending_snapshot *pending_snapshot;
 753         struct btrfs_trans_handle *trans;
 754         int ret;
 755
 756         if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
 757                 return -EINVAL;
 758
 759         if (atomic_read(&root->nr_swapfiles)) {
 760                 btrfs_warn(fs_info,
 761                            "cannot snapshot subvolume with active swapfile");
 762                 return -ETXTBSY;
 763         }
 764
 765         pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
 766         if (!pending_snapshot)
 767                 return -ENOMEM;
 768
 769         ret = get_anon_bdev(&pending_snapshot->anon_dev);
 770         if (ret < 0)
 771                 goto free_pending;
 772         pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
 773                         GFP_KERNEL);
 774         pending_snapshot->path = btrfs_alloc_path();
 775         if (!pending_snapshot->root_item || !pending_snapshot->path) {
 776                 ret = -ENOMEM;
 777                 goto free_pending;
 778         }
 779
 780         btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 781                              BTRFS_BLOCK_RSV_TEMP);
 782         /*
 783          * 1 - parent dir inode
 784          * 2 - dir entries
 785          * 1 - root item
 786          * 2 - root ref/backref
 787          * 1 - root of snapshot
 788          * 1 - UUID item
 789          */
 790         ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 791                                         &pending_snapshot->block_rsv, 8,
 792                                         false);
 793         if (ret)
 794                 goto free_pending;
 795
 796         pending_snapshot->dentry = dentry;
 797         pending_snapshot->root = root;
 798         pending_snapshot->readonly = readonly;
 799         pending_snapshot->dir = dir;
 800         pending_snapshot->inherit = inherit;
 801
 802         trans = btrfs_start_transaction(root, 0);
 803         if (IS_ERR(trans)) {
 804                 ret = PTR_ERR(trans);
 805                 goto fail;
 806         }
 807
 808         trans->pending_snapshot = pending_snapshot;
 809
 810         ret = btrfs_commit_transaction(trans);
 811         if (ret)
 812                 goto fail;
 813
 814         ret = pending_snapshot->error;
 815         if (ret)
 816                 goto fail;
 817
 818         ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 819         if (ret)
 820                 goto fail;
 821
 822         inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
 823         if (IS_ERR(inode)) {
 824                 ret = PTR_ERR(inode);
 825                 goto fail;
 826         }
 827
 828         d_instantiate(dentry, inode);
 829         ret = 0;
 830         pending_snapshot->anon_dev = 0;
 831 fail:
 832         /* Prevent double freeing of anon_dev */
 833         if (ret && pending_snapshot->snap)
 834                 pending_snapshot->snap->anon_dev = 0;
 835         btrfs_put_root(pending_snapshot->snap);
 836         btrfs_subvolume_release_metadata(root, &pending_snapshot->block_rsv);
 837 free_pending:
 838         if (pending_snapshot->anon_dev)
 839                 free_anon_bdev(pending_snapshot->anon_dev);
 840         kfree(pending_snapshot->root_item);
 841         btrfs_free_path(pending_snapshot->path);
 842         kfree(pending_snapshot);
 843
 844         return ret;
 845 }
 846
 847 /*  copy of may_delete in fs/namei.c()
 848  *      Check whether we can remove a link victim from directory dir, check
 849  *  whether the type of victim is right.
 850  *  1. We can't do it if dir is read-only (done in permission())
 851  *  2. We should have write and exec permissions on dir
 852  *  3. We can't remove anything from append-only dir
 853  *  4. We can't do anything with immutable dir (done in permission())
 854  *  5. If the sticky bit on dir is set we should either
 855  *      a. be owner of dir, or
 856  *      b. be owner of victim, or
 857  *      c. have CAP_FOWNER capability
 858  *  6. If the victim is append-only or immutable we can't do anything with
 859  *     links pointing to it.
 860  *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 861  *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 862  *  9. We can't remove a root or mountpoint.
 863  * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 864  *     nfs_async_unlink().
 865  */
 866
 867 static int btrfs_may_delete(struct user_namespace *mnt_userns,
 868                             struct inode *dir, struct dentry *victim, int isdir)
 869 {
 870         int error;
 871
 872         if (d_really_is_negative(victim))
 873                 return -ENOENT;
 874
 875         BUG_ON(d_inode(victim->d_parent) != dir);
 876         audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 877
 878         error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 879         if (error)
 880                 return error;
 881         if (IS_APPEND(dir))
 882                 return -EPERM;
 883         if (check_sticky(mnt_userns, dir, d_inode(victim)) ||
 884             IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
 885             IS_SWAPFILE(d_inode(victim)))
 886                 return -EPERM;
 887         if (isdir) {
 888                 if (!d_is_dir(victim))
 889                         return -ENOTDIR;
 890                 if (IS_ROOT(victim))
 891                         return -EBUSY;
 892         } else if (d_is_dir(victim))
 893                 return -EISDIR;
 894         if (IS_DEADDIR(dir))
 895                 return -ENOENT;
 896         if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 897                 return -EBUSY;
 898         return 0;
 899 }
 900
 901 /* copy of may_create in fs/namei.c() */
 902 static inline int btrfs_may_create(struct user_namespace *mnt_userns,
 903                                    struct inode *dir, struct dentry *child)
 904 {
 905         if (d_really_is_positive(child))
 906                 return -EEXIST;
 907         if (IS_DEADDIR(dir))
 908                 return -ENOENT;
 909         if (!fsuidgid_has_mapping(dir->i_sb, mnt_userns))
 910                 return -EOVERFLOW;
 911         return inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 912 }
 913
 914 /*
 915  * Create a new subvolume below @parent.  This is largely modeled after
 916  * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 917  * inside this filesystem so it's quite a bit simpler.
 918  */
 919 static noinline int btrfs_mksubvol(const struct path *parent,
 920                                    struct user_namespace *mnt_userns,
 921                                    const char *name, int namelen,
 922                                    struct btrfs_root *snap_src,
 923                                    bool readonly,
 924                                    struct btrfs_qgroup_inherit *inherit)
 925 {
 926         struct inode *dir = d_inode(parent->dentry);
 927         struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 928         struct dentry *dentry;
 929         int error;
 930
 931         error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
 932         if (error == -EINTR)
 933                 return error;
 934
 935         dentry = lookup_one(mnt_userns, name, parent->dentry, namelen);
 936         error = PTR_ERR(dentry);
 937         if (IS_ERR(dentry))
 938                 goto out_unlock;
 939
 940         error = btrfs_may_create(mnt_userns, dir, dentry);
 941         if (error)
 942                 goto out_dput;
 943
 944         /*
 945          * even if this name doesn't exist, we may get hash collisions.
 946          * check for them now when we can safely fail
 947          */
 948         error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 949                                                dir->i_ino, name,
 950                                                namelen);
 951         if (error)
 952                 goto out_dput;
 953
 954         down_read(&fs_info->subvol_sem);
 955
 956         if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 957                 goto out_up_read;
 958
 959         if (snap_src)
 960                 error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
 961         else
 962                 error = create_subvol(mnt_userns, dir, dentry, name, namelen, inherit);
 963
 964         if (!error)
 965                 fsnotify_mkdir(dir, dentry);
 966 out_up_read:
 967         up_read(&fs_info->subvol_sem);
 968 out_dput:
 969         dput(dentry);
 970 out_unlock:
 971         btrfs_inode_unlock(dir, 0);
 972         return error;
 973 }
 974
 975 static noinline int btrfs_mksnapshot(const struct path *parent,
 976                                    struct user_namespace *mnt_userns,
 977                                    const char *name, int namelen,
 978                                    struct btrfs_root *root,
 979                                    bool readonly,
 980                                    struct btrfs_qgroup_inherit *inherit)
 981 {
 982         int ret;
 983         bool snapshot_force_cow = false;
 984
 985         /*
 986          * Force new buffered writes to reserve space even when NOCOW is
 987          * possible. This is to avoid later writeback (running dealloc) to
 988          * fallback to COW mode and unexpectedly fail with ENOSPC.
 989          */
 990         btrfs_drew_read_lock(&root->snapshot_lock);
 991
 992         ret = btrfs_start_delalloc_snapshot(root, false);
 993         if (ret)
 994                 goto out;
 995
 996         /*
 997          * All previous writes have started writeback in NOCOW mode, so now
 998          * we force future writes to fallback to COW mode during snapshot
 999          * creation.
1000          */
1001         atomic_inc(&root->snapshot_force_cow);
1002         snapshot_force_cow = true;
1003
1004         btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
1005
1006         ret = btrfs_mksubvol(parent, mnt_userns, name, namelen,
1007                              root, readonly, inherit);
1008 out:
1009         if (snapshot_force_cow)
1010                 atomic_dec(&root->snapshot_force_cow);
1011         btrfs_drew_read_unlock(&root->snapshot_lock);
1012         return ret;
1013 }
1014
1015 static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start,
1016                                                bool locked)
1017 {
1018         struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1019         struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1020         struct extent_map *em;
1021         const u32 sectorsize = BTRFS_I(inode)->root->fs_info->sectorsize;
1022
1023         /*
1024          * hopefully we have this extent in the tree already, try without
1025          * the full extent lock
1026          */
1027         read_lock(&em_tree->lock);
1028         em = lookup_extent_mapping(em_tree, start, sectorsize);
1029         read_unlock(&em_tree->lock);
1030
1031         if (!em) {
1032                 struct extent_state *cached = NULL;
1033                 u64 end = start + sectorsize - 1;
1034
1035                 /* get the big lock and read metadata off disk */
1036                 if (!locked)
1037                         lock_extent_bits(io_tree, start, end, &cached);
1038                 em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, sectorsize);
1039                 if (!locked)
1040                         unlock_extent_cached(io_tree, start, end, &cached);
1041
1042                 if (IS_ERR(em))
1043                         return NULL;
1044         }
1045
1046         return em;
1047 }
1048
1049 static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em,
1050                                      bool locked)
1051 {
1052         struct extent_map *next;
1053         bool ret = true;
1054
1055         /* this is the last extent */
1056         if (em->start + em->len >= i_size_read(inode))
1057                 return false;
1058
1059         next = defrag_lookup_extent(inode, em->start + em->len, locked);
1060         if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1061                 ret = false;
1062         else if ((em->block_start + em->block_len == next->block_start) &&
1063                  (em->block_len > SZ_128K && next->block_len > SZ_128K))
1064                 ret = false;
1065
1066         free_extent_map(next);
1067         return ret;
1068 }
1069
1070 /*
1071  * Prepare one page to be defragged.
1072  *
1073  * This will ensure:
1074  *
1075  * - Returned page is locked and has been set up properly.
1076  * - No ordered extent exists in the page.
1077  * - The page is uptodate.
1078  *
1079  * NOTE: Caller should also wait for page writeback after the cluster is
1080  * prepared, here we don't do writeback wait for each page.
1081  */
1082 static struct page *defrag_prepare_one_page(struct btrfs_inode *inode,
1083                                             pgoff_t index)
1084 {
1085         struct address_space *mapping = inode->vfs_inode.i_mapping;
1086         gfp_t mask = btrfs_alloc_write_mask(mapping);
1087         u64 page_start = (u64)index << PAGE_SHIFT;
1088         u64 page_end = page_start + PAGE_SIZE - 1;
1089         struct extent_state *cached_state = NULL;
1090         struct page *page;
1091         int ret;
1092
1093 again:
1094         page = find_or_create_page(mapping, index, mask);
1095         if (!page)
1096                 return ERR_PTR(-ENOMEM);
1097
1098         /*
1099          * Since we can defragment files opened read-only, we can encounter
1100          * transparent huge pages here (see CONFIG_READ_ONLY_THP_FOR_FS). We
1101          * can't do I/O using huge pages yet, so return an error for now.
1102          * Filesystem transparent huge pages are typically only used for
1103          * executables that explicitly enable them, so this isn't very
1104          * restrictive.
1105          */
1106         if (PageCompound(page)) {
1107                 unlock_page(page);
1108                 put_page(page);
1109                 return ERR_PTR(-ETXTBSY);
1110         }
1111
1112         ret = set_page_extent_mapped(page);
1113         if (ret < 0) {
1114                 unlock_page(page);
1115                 put_page(page);
1116                 return ERR_PTR(ret);
1117         }
1118
1119         /* Wait for any existing ordered extent in the range */
1120         while (1) {
1121                 struct btrfs_ordered_extent *ordered;
1122
1123                 lock_extent_bits(&inode->io_tree, page_start, page_end, &cached_state);
1124                 ordered = btrfs_lookup_ordered_range(inode, page_start, PAGE_SIZE);
1125                 unlock_extent_cached(&inode->io_tree, page_start, page_end,
1126                                      &cached_state);
1127                 if (!ordered)
1128                         break;
1129
1130                 unlock_page(page);
1131                 btrfs_start_ordered_extent(ordered, 1);
1132                 btrfs_put_ordered_extent(ordered);
1133                 lock_page(page);
1134                 /*
1135                  * We unlocked the page above, so we need check if it was
1136                  * released or not.
1137                  */
1138                 if (page->mapping != mapping || !PagePrivate(page)) {
1139                         unlock_page(page);
1140                         put_page(page);
1141                         goto again;
1142                 }
1143         }
1144
1145         /*
1146          * Now the page range has no ordered extent any more.  Read the page to
1147          * make it uptodate.
1148          */
1149         if (!PageUptodate(page)) {
1150                 btrfs_readpage(NULL, page);
1151                 lock_page(page);
1152                 if (page->mapping != mapping || !PagePrivate(page)) {
1153                         unlock_page(page);
1154                         put_page(page);
1155                         goto again;
1156                 }
1157                 if (!PageUptodate(page)) {
1158                         unlock_page(page);
1159                         put_page(page);
1160                         return ERR_PTR(-EIO);
1161                 }
1162         }
1163         return page;
1164 }
1165
1166 struct defrag_target_range {
1167         struct list_head list;
1168         u64 start;
1169         u64 len;
1170 };
1171
1172 /*
1173  * Collect all valid target extents.
1174  *
1175  * @start:         file offset to lookup
1176  * @len:           length to lookup
1177  * @extent_thresh: file extent size threshold, any extent size >= this value
1178  *                 will be ignored
1179  * @newer_than:    only defrag extents newer than this value
1180  * @do_compress:   whether the defrag is doing compression
1181  *                 if true, @extent_thresh will be ignored and all regular
1182  *                 file extents meeting @newer_than will be targets.
1183  * @locked:        if the range has already held extent lock
1184  * @target_list:   list of targets file extents
1185  */
1186 static int defrag_collect_targets(struct btrfs_inode *inode,
1187                                   u64 start, u64 len, u32 extent_thresh,
1188                                   u64 newer_than, bool do_compress,
1189                                   bool locked, struct list_head *target_list)
1190 {
1191         u64 cur = start;
1192         int ret = 0;
1193
1194         while (cur < start + len) {
1195                 struct extent_map *em;
1196                 struct defrag_target_range *new;
1197                 bool next_mergeable = true;
1198                 u64 range_len;
1199
1200                 em = defrag_lookup_extent(&inode->vfs_inode, cur, locked);
1201                 if (!em)
1202                         break;
1203
1204                 /* Skip hole/inline/preallocated extents */
1205                 if (em->block_start >= EXTENT_MAP_LAST_BYTE ||
1206                     test_bit(EXTENT_FLAG_PREALLOC, &em->flags))
1207                         goto next;
1208
1209                 /* Skip older extent */
1210                 if (em->generation < newer_than)
1211                         goto next;
1212
1213                 /* This em is under writeback, no need to defrag */
1214                 if (em->generation == (u64)-1)
1215                         goto next;
1216
1217                 /*
1218                  * Our start offset might be in the middle of an existing extent
1219                  * map, so take that into account.
1220                  */
1221                 range_len = em->len - (cur - em->start);
1222                 /*
1223                  * If this range of the extent map is already flagged for delalloc,
1224                  * skip it, because:
1225                  *
1226                  * 1) We could deadlock later, when trying to reserve space for
1227                  *    delalloc, because in case we can't immediately reserve space
1228                  *    the flusher can start delalloc and wait for the respective
1229                  *    ordered extents to complete. The deadlock would happen
1230                  *    because we do the space reservation while holding the range
1231                  *    locked, and starting writeback, or finishing an ordered
1232                  *    extent, requires locking the range;
1233                  *
1234                  * 2) If there's delalloc there, it means there's dirty pages for
1235                  *    which writeback has not started yet (we clean the delalloc
1236                  *    flag when starting writeback and after creating an ordered
1237                  *    extent). If we mark pages in an adjacent range for defrag,
1238                  *    then we will have a larger contiguous range for delalloc,
1239                  *    very likely resulting in a larger extent after writeback is
1240                  *    triggered (except in a case of free space fragmentation).
1241                  */
1242                 if (test_range_bit(&inode->io_tree, cur, cur + range_len - 1,
1243                                    EXTENT_DELALLOC, 0, NULL))
1244                         goto next;
1245
1246                 /*
1247                  * For do_compress case, we want to compress all valid file
1248                  * extents, thus no @extent_thresh or mergeable check.
1249                  */
1250                 if (do_compress)
1251                         goto add;
1252
1253                 /* Skip too large extent */
1254                 if (range_len >= extent_thresh)
1255                         goto next;
1256
1257                 next_mergeable = defrag_check_next_extent(&inode->vfs_inode, em,
1258                                                           locked);
1259                 if (!next_mergeable) {
1260                         struct defrag_target_range *last;
1261
1262                         /* Empty target list, no way to merge with last entry */
1263                         if (list_empty(target_list))
1264                                 goto next;
1265                         last = list_entry(target_list->prev,
1266                                           struct defrag_target_range, list);
1267                         /* Not mergeable with last entry */
1268                         if (last->start + last->len != cur)
1269                                 goto next;
1270
1271                         /* Mergeable, fall through to add it to @target_list. */
1272                 }
1273
1274 add:
1275                 range_len = min(extent_map_end(em), start + len) - cur;
1276                 /*
1277                  * This one is a good target, check if it can be merged into
1278                  * last range of the target list.
1279                  */
1280                 if (!list_empty(target_list)) {
1281                         struct defrag_target_range *last;
1282
1283                         last = list_entry(target_list->prev,
1284                                           struct defrag_target_range, list);
1285                         ASSERT(last->start + last->len <= cur);
1286                         if (last->start + last->len == cur) {
1287                                 /* Mergeable, enlarge the last entry */
1288                                 last->len += range_len;
1289                                 goto next;
1290                         }
1291                         /* Fall through to allocate a new entry */
1292                 }
1293
1294                 /* Allocate new defrag_target_range */
1295                 new = kmalloc(sizeof(*new), GFP_NOFS);
1296                 if (!new) {
1297                         free_extent_map(em);
1298                         ret = -ENOMEM;
1299                         break;
1300                 }
1301                 new->start = cur;
1302                 new->len = range_len;
1303                 list_add_tail(&new->list, target_list);
1304
1305 next:
1306                 cur = extent_map_end(em);
1307                 free_extent_map(em);
1308         }
1309         if (ret < 0) {
1310                 struct defrag_target_range *entry;
1311                 struct defrag_target_range *tmp;
1312
1313                 list_for_each_entry_safe(entry, tmp, target_list, list) {
1314                         list_del_init(&entry->list);
1315                         kfree(entry);
1316                 }
1317         }
1318         return ret;
1319 }
1320
1321 #define CLUSTER_SIZE    (SZ_256K)
1322
1323 /*
1324  * Defrag one contiguous target range.
1325  *
1326  * @inode:      target inode
1327  * @target:     target range to defrag
1328  * @pages:      locked pages covering the defrag range
1329  * @nr_pages:   number of locked pages
1330  *
1331  * Caller should ensure:
1332  *
1333  * - Pages are prepared
1334  *   Pages should be locked, no ordered extent in the pages range,
1335  *   no writeback.
1336  *
1337  * - Extent bits are locked
1338  */
1339 static int defrag_one_locked_target(struct btrfs_inode *inode,
1340                                     struct defrag_target_range *target,
1341                                     struct page **pages, int nr_pages,
1342                                     struct extent_state **cached_state)
1343 {
1344         struct btrfs_fs_info *fs_info = inode->root->fs_info;
1345         struct extent_changeset *data_reserved = NULL;
1346         const u64 start = target->start;
1347         const u64 len = target->len;
1348         unsigned long last_index = (start + len - 1) >> PAGE_SHIFT;
1349         unsigned long start_index = start >> PAGE_SHIFT;
1350         unsigned long first_index = page_index(pages[0]);
1351         int ret = 0;
1352         int i;
1353
1354         ASSERT(last_index - first_index + 1 <= nr_pages);
1355
1356         ret = btrfs_delalloc_reserve_space(inode, &data_reserved, start, len);
1357         if (ret < 0)
1358                 return ret;
1359         clear_extent_bit(&inode->io_tree, start, start + len - 1,
1360                          EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
1361                          EXTENT_DEFRAG, 0, 0, cached_state);
1362         set_extent_defrag(&inode->io_tree, start, start + len - 1, cached_state);
1363
1364         /* Update the page status */
1365         for (i = start_index - first_index; i <= last_index - first_index; i++) {
1366                 ClearPageChecked(pages[i]);
1367                 btrfs_page_clamp_set_dirty(fs_info, pages[i], start, len);
1368         }
1369         btrfs_delalloc_release_extents(inode, len);
1370         extent_changeset_free(data_reserved);
1371
1372         return ret;
1373 }
1374
1375 static int defrag_one_range(struct btrfs_inode *inode, u64 start, u32 len,
1376                             u32 extent_thresh, u64 newer_than, bool do_compress)
1377 {
1378         struct extent_state *cached_state = NULL;
1379         struct defrag_target_range *entry;
1380         struct defrag_target_range *tmp;
1381         LIST_HEAD(target_list);
1382         struct page **pages;
1383         const u32 sectorsize = inode->root->fs_info->sectorsize;
1384         u64 last_index = (start + len - 1) >> PAGE_SHIFT;
1385         u64 start_index = start >> PAGE_SHIFT;
1386         unsigned int nr_pages = last_index - start_index + 1;
1387         int ret = 0;
1388         int i;
1389
1390         ASSERT(nr_pages <= CLUSTER_SIZE / PAGE_SIZE);
1391         ASSERT(IS_ALIGNED(start, sectorsize) && IS_ALIGNED(len, sectorsize));
1392
1393         pages = kcalloc(nr_pages, sizeof(struct page *), GFP_NOFS);
1394         if (!pages)
1395                 return -ENOMEM;
1396
1397         /* Prepare all pages */
1398         for (i = 0; i < nr_pages; i++) {
1399                 pages[i] = defrag_prepare_one_page(inode, start_index + i);
1400                 if (IS_ERR(pages[i])) {
1401                         ret = PTR_ERR(pages[i]);
1402                         pages[i] = NULL;
1403                         goto free_pages;
1404                 }
1405         }
1406         for (i = 0; i < nr_pages; i++)
1407                 wait_on_page_writeback(pages[i]);
1408
1409         /* Lock the pages range */
1410         lock_extent_bits(&inode->io_tree, start_index << PAGE_SHIFT,
1411                          (last_index << PAGE_SHIFT) + PAGE_SIZE - 1,
1412                          &cached_state);
1413         /*
1414          * Now we have a consistent view about the extent map, re-check
1415          * which range really needs to be defragged.
1416          *
1417          * And this time we have extent locked already, pass @locked = true
1418          * so that we won't relock the extent range and cause deadlock.
1419          */
1420         ret = defrag_collect_targets(inode, start, len, extent_thresh,
1421                                      newer_than, do_compress, true,
1422                                      &target_list);
1423         if (ret < 0)
1424                 goto unlock_extent;
1425
1426         list_for_each_entry(entry, &target_list, list) {
1427                 ret = defrag_one_locked_target(inode, entry, pages, nr_pages,
1428                                                &cached_state);
1429                 if (ret < 0)
1430                         break;
1431         }
1432
1433         list_for_each_entry_safe(entry, tmp, &target_list, list) {
1434                 list_del_init(&entry->list);
1435                 kfree(entry);
1436         }
1437 unlock_extent:
1438         unlock_extent_cached(&inode->io_tree, start_index << PAGE_SHIFT,
1439                              (last_index << PAGE_SHIFT) + PAGE_SIZE - 1,
1440                              &cached_state);
1441 free_pages:
1442         for (i = 0; i < nr_pages; i++) {
1443                 if (pages[i]) {
1444                         unlock_page(pages[i]);
1445                         put_page(pages[i]);
1446                 }
1447         }
1448         kfree(pages);
1449         return ret;
1450 }
1451
1452 static int defrag_one_cluster(struct btrfs_inode *inode,
1453                               struct file_ra_state *ra,
1454                               u64 start, u32 len, u32 extent_thresh,
1455                               u64 newer_than, bool do_compress,
1456                               unsigned long *sectors_defragged,
1457                               unsigned long max_sectors)
1458 {
1459         const u32 sectorsize = inode->root->fs_info->sectorsize;
1460         struct defrag_target_range *entry;
1461         struct defrag_target_range *tmp;
1462         LIST_HEAD(target_list);
1463         int ret;
1464
1465         BUILD_BUG_ON(!IS_ALIGNED(CLUSTER_SIZE, PAGE_SIZE));
1466         ret = defrag_collect_targets(inode, start, len, extent_thresh,
1467                                      newer_than, do_compress, false,
1468                                      &target_list);
1469         if (ret < 0)
1470                 goto out;
1471
1472         list_for_each_entry(entry, &target_list, list) {
1473                 u32 range_len = entry->len;
1474
1475                 /* Reached or beyond the limit */
1476                 if (max_sectors && *sectors_defragged >= max_sectors) {
1477                         ret = 1;
1478                         break;
1479                 }
1480
1481                 if (max_sectors)
1482                         range_len = min_t(u32, range_len,
1483                                 (max_sectors - *sectors_defragged) * sectorsize);
1484
1485                 if (ra)
1486                         page_cache_sync_readahead(inode->vfs_inode.i_mapping,
1487                                 ra, NULL, entry->start >> PAGE_SHIFT,
1488                                 ((entry->start + range_len - 1) >> PAGE_SHIFT) -
1489                                 (entry->start >> PAGE_SHIFT) + 1);
1490                 /*
1491                  * Here we may not defrag any range if holes are punched before
1492                  * we locked the pages.
1493                  * But that's fine, it only affects the @sectors_defragged
1494                  * accounting.
1495                  */
1496                 ret = defrag_one_range(inode, entry->start, range_len,
1497                                        extent_thresh, newer_than, do_compress);
1498                 if (ret < 0)
1499                         break;
1500                 *sectors_defragged += range_len >>
1501                                       inode->root->fs_info->sectorsize_bits;
1502         }
1503 out:
1504         list_for_each_entry_safe(entry, tmp, &target_list, list) {
1505                 list_del_init(&entry->list);
1506                 kfree(entry);
1507         }
1508         return ret;
1509 }
1510
1511 /*
1512  * Entry point to file defragmentation.
1513  *
1514  * @inode:         inode to be defragged
1515  * @ra:            readahead state (can be NUL)
1516  * @range:         defrag options including range and flags
1517  * @newer_than:    minimum transid to defrag
1518  * @max_to_defrag: max number of sectors to be defragged, if 0, the whole inode
1519  *                 will be defragged.
1520  *
1521  * Return <0 for error.
1522  * Return >=0 for the number of sectors defragged, and range->start will be updated
1523  * to indicate the file offset where next defrag should be started at.
1524  * (Mostly for autodefrag, which sets @max_to_defrag thus we may exit early without
1525  *  defragging all the range).
1526  */
1527 int btrfs_defrag_file(struct inode *inode, struct file_ra_state *ra,
1528                       struct btrfs_ioctl_defrag_range_args *range,
1529                       u64 newer_than, unsigned long max_to_defrag)
1530 {
1531         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1532         unsigned long sectors_defragged = 0;
1533         u64 isize = i_size_read(inode);
1534         u64 cur;
1535         u64 last_byte;
1536         bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1537         bool ra_allocated = false;
1538         int compress_type = BTRFS_COMPRESS_ZLIB;
1539         int ret = 0;
1540         u32 extent_thresh = range->extent_thresh;
1541         pgoff_t start_index;
1542
1543         if (isize == 0)
1544                 return 0;
1545
1546         if (range->start >= isize)
1547                 return -EINVAL;
1548
1549         if (do_compress) {
1550                 if (range->compress_type >= BTRFS_NR_COMPRESS_TYPES)
1551                         return -EINVAL;
1552                 if (range->compress_type)
1553                         compress_type = range->compress_type;
1554         }
1555
1556         if (extent_thresh == 0)
1557                 extent_thresh = SZ_256K;
1558
1559         if (range->start + range->len > range->start) {
1560                 /* Got a specific range */
1561                 last_byte = min(isize, range->start + range->len);
1562         } else {
1563                 /* Defrag until file end */
1564                 last_byte = isize;
1565         }
1566
1567         /* Align the range */
1568         cur = round_down(range->start, fs_info->sectorsize);
1569         last_byte = round_up(last_byte, fs_info->sectorsize) - 1;
1570
1571         /*
1572          * If we were not given a ra, allocate a readahead context. As
1573          * readahead is just an optimization, defrag will work without it so
1574          * we don't error out.
1575          */
1576         if (!ra) {
1577                 ra_allocated = true;
1578                 ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1579                 if (ra)
1580                         file_ra_state_init(ra, inode->i_mapping);
1581         }
1582
1583         /*
1584          * Make writeback start from the beginning of the range, so that the
1585          * defrag range can be written sequentially.
1586          */
1587         start_index = cur >> PAGE_SHIFT;
1588         if (start_index < inode->i_mapping->writeback_index)
1589                 inode->i_mapping->writeback_index = start_index;
1590
1591         while (cur < last_byte) {
1592                 const unsigned long prev_sectors_defragged = sectors_defragged;
1593                 u64 cluster_end;
1594
1595                 /* The cluster size 256K should always be page aligned */
1596                 BUILD_BUG_ON(!IS_ALIGNED(CLUSTER_SIZE, PAGE_SIZE));
1597
1598                 if (btrfs_defrag_cancelled(fs_info)) {
1599                         ret = -EAGAIN;
1600                         break;
1601                 }
1602
1603                 /* We want the cluster end at page boundary when possible */
1604                 cluster_end = (((cur >> PAGE_SHIFT) +
1605                                (SZ_256K >> PAGE_SHIFT)) << PAGE_SHIFT) - 1;
1606                 cluster_end = min(cluster_end, last_byte);
1607
1608                 btrfs_inode_lock(inode, 0);
1609                 if (IS_SWAPFILE(inode)) {
1610                         ret = -ETXTBSY;
1611                         btrfs_inode_unlock(inode, 0);
1612                         break;
1613                 }
1614                 if (!(inode->i_sb->s_flags & SB_ACTIVE)) {
1615                         btrfs_inode_unlock(inode, 0);
1616                         break;
1617                 }
1618                 if (do_compress)
1619                         BTRFS_I(inode)->defrag_compress = compress_type;
1620                 ret = defrag_one_cluster(BTRFS_I(inode), ra, cur,
1621                                 cluster_end + 1 - cur, extent_thresh,
1622                                 newer_than, do_compress,
1623                                 &sectors_defragged, max_to_defrag);
1624
1625                 if (sectors_defragged > prev_sectors_defragged)
1626                         balance_dirty_pages_ratelimited(inode->i_mapping);
1627
1628                 btrfs_inode_unlock(inode, 0);
1629                 if (ret < 0)
1630                         break;
1631                 cur = cluster_end + 1;
1632                 if (ret > 0) {
1633                         ret = 0;
1634                         break;
1635                 }
1636                 cond_resched();
1637         }
1638
1639         if (ra_allocated)
1640                 kfree(ra);
1641         /*
1642          * Update range.start for autodefrag, this will indicate where to start
1643          * in next run.
1644          */
1645         range->start = cur;
1646         if (sectors_defragged) {
1647                 /*
1648                  * We have defragged some sectors, for compression case they
1649                  * need to be written back immediately.
1650                  */
1651                 if (range->flags & BTRFS_DEFRAG_RANGE_START_IO) {
1652                         filemap_flush(inode->i_mapping);
1653                         if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1654                                      &BTRFS_I(inode)->runtime_flags))
1655                                 filemap_flush(inode->i_mapping);
1656                 }
1657                 if (range->compress_type == BTRFS_COMPRESS_LZO)
1658                         btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1659                 else if (range->compress_type == BTRFS_COMPRESS_ZSTD)
1660                         btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1661                 ret = sectors_defragged;
1662         }
1663         if (do_compress) {
1664                 btrfs_inode_lock(inode, 0);
1665                 BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1666                 btrfs_inode_unlock(inode, 0);
1667         }
1668         return ret;
1669 }
1670
1671 /*
1672  * Try to start exclusive operation @type or cancel it if it's running.
1673  *
1674  * Return:
1675  *   0        - normal mode, newly claimed op started
1676  *  >0        - normal mode, something else is running,
1677  *              return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space
1678  * ECANCELED  - cancel mode, successful cancel
1679  * ENOTCONN   - cancel mode, operation not running anymore
1680  */
1681 static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,
1682                         enum btrfs_exclusive_operation type, bool cancel)
1683 {
1684         if (!cancel) {
1685                 /* Start normal op */
1686                 if (!btrfs_exclop_start(fs_info, type))
1687                         return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1688                 /* Exclusive operation is now claimed */
1689                 return 0;
1690         }
1691
1692         /* Cancel running op */
1693         if (btrfs_exclop_start_try_lock(fs_info, type)) {
1694                 /*
1695                  * This blocks any exclop finish from setting it to NONE, so we
1696                  * request cancellation. Either it runs and we will wait for it,
1697                  * or it has finished and no waiting will happen.
1698                  */
1699                 atomic_inc(&fs_info->reloc_cancel_req);
1700                 btrfs_exclop_start_unlock(fs_info);
1701
1702                 if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))
1703                         wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,
1704                                     TASK_INTERRUPTIBLE);
1705
1706                 return -ECANCELED;
1707         }
1708
1709         /* Something else is running or none */
1710         return -ENOTCONN;
1711 }
1712
1713 static noinline int btrfs_ioctl_resize(struct file *file,
1714                                         void __user *arg)
1715 {
1716         BTRFS_DEV_LOOKUP_ARGS(args);
1717         struct inode *inode = file_inode(file);
1718         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1719         u64 new_size;
1720         u64 old_size;
1721         u64 devid = 1;
1722         struct btrfs_root *root = BTRFS_I(inode)->root;
1723         struct btrfs_ioctl_vol_args *vol_args;
1724         struct btrfs_trans_handle *trans;
1725         struct btrfs_device *device = NULL;
1726         char *sizestr;
1727         char *retptr;
1728         char *devstr = NULL;
1729         int ret = 0;
1730         int mod = 0;
1731         bool cancel;
1732
1733         if (!capable(CAP_SYS_ADMIN))
1734                 return -EPERM;
1735
1736         ret = mnt_want_write_file(file);
1737         if (ret)
1738                 return ret;
1739
1740         /*
1741          * Read the arguments before checking exclusivity to be able to
1742          * distinguish regular resize and cancel
1743          */
1744         vol_args = memdup_user(arg, sizeof(*vol_args));
1745         if (IS_ERR(vol_args)) {
1746                 ret = PTR_ERR(vol_args);
1747                 goto out_drop;
1748         }
1749         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1750         sizestr = vol_args->name;
1751         cancel = (strcmp("cancel", sizestr) == 0);
1752         ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);
1753         if (ret)
1754                 goto out_free;
1755         /* Exclusive operation is now claimed */
1756
1757         devstr = strchr(sizestr, ':');
1758         if (devstr) {
1759                 sizestr = devstr + 1;
1760                 *devstr = '\0';
1761                 devstr = vol_args->name;
1762                 ret = kstrtoull(devstr, 10, &devid);
1763                 if (ret)
1764                         goto out_finish;
1765                 if (!devid) {
1766                         ret = -EINVAL;
1767                         goto out_finish;
1768                 }
1769                 btrfs_info(fs_info, "resizing devid %llu", devid);
1770         }
1771
1772         args.devid = devid;
1773         device = btrfs_find_device(fs_info->fs_devices, &args);
1774         if (!device) {
1775                 btrfs_info(fs_info, "resizer unable to find device %llu",
1776                            devid);
1777                 ret = -ENODEV;
1778                 goto out_finish;
1779         }
1780
1781         if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1782                 btrfs_info(fs_info,
1783                            "resizer unable to apply on readonly device %llu",
1784                        devid);
1785                 ret = -EPERM;
1786                 goto out_finish;
1787         }
1788
1789         if (!strcmp(sizestr, "max"))
1790                 new_size = bdev_nr_bytes(device->bdev);
1791         else {
1792                 if (sizestr[0] == '-') {
1793                         mod = -1;
1794                         sizestr++;
1795                 } else if (sizestr[0] == '+') {
1796                         mod = 1;
1797                         sizestr++;
1798                 }
1799                 new_size = memparse(sizestr, &retptr);
1800                 if (*retptr != '\0' || new_size == 0) {
1801                         ret = -EINVAL;
1802                         goto out_finish;
1803                 }
1804         }
1805
1806         if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1807                 ret = -EPERM;
1808                 goto out_finish;
1809         }
1810
1811         old_size = btrfs_device_get_total_bytes(device);
1812
1813         if (mod < 0) {
1814                 if (new_size > old_size) {
1815                         ret = -EINVAL;
1816                         goto out_finish;
1817                 }
1818                 new_size = old_size - new_size;
1819         } else if (mod > 0) {
1820                 if (new_size > ULLONG_MAX - old_size) {
1821                         ret = -ERANGE;
1822                         goto out_finish;
1823                 }
1824                 new_size = old_size + new_size;
1825         }
1826
1827         if (new_size < SZ_256M) {
1828                 ret = -EINVAL;
1829                 goto out_finish;
1830         }
1831         if (new_size > bdev_nr_bytes(device->bdev)) {
1832                 ret = -EFBIG;
1833                 goto out_finish;
1834         }
1835
1836         new_size = round_down(new_size, fs_info->sectorsize);
1837
1838         if (new_size > old_size) {
1839                 trans = btrfs_start_transaction(root, 0);
1840                 if (IS_ERR(trans)) {
1841                         ret = PTR_ERR(trans);
1842                         goto out_finish;
1843                 }
1844                 ret = btrfs_grow_device(trans, device, new_size);
1845                 btrfs_commit_transaction(trans);
1846         } else if (new_size < old_size) {
1847                 ret = btrfs_shrink_device(device, new_size);
1848         } /* equal, nothing need to do */
1849
1850         if (ret == 0 && new_size != old_size)
1851                 btrfs_info_in_rcu(fs_info,
1852                         "resize device %s (devid %llu) from %llu to %llu",
1853                         rcu_str_deref(device->name), device->devid,
1854                         old_size, new_size);
1855 out_finish:
1856         btrfs_exclop_finish(fs_info);
1857 out_free:
1858         kfree(vol_args);
1859 out_drop:
1860         mnt_drop_write_file(file);
1861         return ret;
1862 }
1863
1864 static noinline int __btrfs_ioctl_snap_create(struct file *file,
1865                                 struct user_namespace *mnt_userns,
1866                                 const char *name, unsigned long fd, int subvol,
1867                                 bool readonly,
1868                                 struct btrfs_qgroup_inherit *inherit)
1869 {
1870         int namelen;
1871         int ret = 0;
1872
1873         if (!S_ISDIR(file_inode(file)->i_mode))
1874                 return -ENOTDIR;
1875
1876         ret = mnt_want_write_file(file);
1877         if (ret)
1878                 goto out;
1879
1880         namelen = strlen(name);
1881         if (strchr(name, '/')) {
1882                 ret = -EINVAL;
1883                 goto out_drop_write;
1884         }
1885
1886         if (name[0] == '.' &&
1887            (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1888                 ret = -EEXIST;
1889                 goto out_drop_write;
1890         }
1891
1892         if (subvol) {
1893                 ret = btrfs_mksubvol(&file->f_path, mnt_userns, name,
1894                                      namelen, NULL, readonly, inherit);
1895         } else {
1896                 struct fd src = fdget(fd);
1897                 struct inode *src_inode;
1898                 if (!src.file) {
1899                         ret = -EINVAL;
1900                         goto out_drop_write;
1901                 }
1902
1903                 src_inode = file_inode(src.file);
1904                 if (src_inode->i_sb != file_inode(file)->i_sb) {
1905                         btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1906                                    "Snapshot src from another FS");
1907                         ret = -EXDEV;
1908                 } else if (!inode_owner_or_capable(mnt_userns, src_inode)) {
1909                         /*
1910                          * Subvolume creation is not restricted, but snapshots
1911                          * are limited to own subvolumes only
1912                          */
1913                         ret = -EPERM;
1914                 } else {
1915                         ret = btrfs_mksnapshot(&file->f_path, mnt_userns,
1916                                                name, namelen,
1917                                                BTRFS_I(src_inode)->root,
1918                                                readonly, inherit);
1919                 }
1920                 fdput(src);
1921         }
1922 out_drop_write:
1923         mnt_drop_write_file(file);
1924 out:
1925         return ret;
1926 }
1927
1928 static noinline int btrfs_ioctl_snap_create(struct file *file,
1929                                             void __user *arg, int subvol)
1930 {
1931         struct btrfs_ioctl_vol_args *vol_args;
1932         int ret;
1933
1934         if (!S_ISDIR(file_inode(file)->i_mode))
1935                 return -ENOTDIR;
1936
1937         vol_args = memdup_user(arg, sizeof(*vol_args));
1938         if (IS_ERR(vol_args))
1939                 return PTR_ERR(vol_args);
1940         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1941
1942         ret = __btrfs_ioctl_snap_create(file, file_mnt_user_ns(file),
1943                                         vol_args->name, vol_args->fd, subvol,
1944                                         false, NULL);
1945
1946         kfree(vol_args);
1947         return ret;
1948 }
1949
1950 static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1951                                                void __user *arg, int subvol)
1952 {
1953         struct btrfs_ioctl_vol_args_v2 *vol_args;
1954         int ret;
1955         bool readonly = false;
1956         struct btrfs_qgroup_inherit *inherit = NULL;
1957
1958         if (!S_ISDIR(file_inode(file)->i_mode))
1959                 return -ENOTDIR;
1960
1961         vol_args = memdup_user(arg, sizeof(*vol_args));
1962         if (IS_ERR(vol_args))
1963                 return PTR_ERR(vol_args);
1964         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1965
1966         if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
1967                 ret = -EOPNOTSUPP;
1968                 goto free_args;
1969         }
1970
1971         if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1972                 readonly = true;
1973         if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1974                 u64 nums;
1975
1976                 if (vol_args->size < sizeof(*inherit) ||
1977                     vol_args->size > PAGE_SIZE) {
1978                         ret = -EINVAL;
1979                         goto free_args;
1980                 }
1981                 inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1982                 if (IS_ERR(inherit)) {
1983                         ret = PTR_ERR(inherit);
1984                         goto free_args;
1985                 }
1986
1987                 if (inherit->num_qgroups > PAGE_SIZE ||
1988                     inherit->num_ref_copies > PAGE_SIZE ||
1989                     inherit->num_excl_copies > PAGE_SIZE) {
1990                         ret = -EINVAL;
1991                         goto free_inherit;
1992                 }
1993
1994                 nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
1995                        2 * inherit->num_excl_copies;
1996                 if (vol_args->size != struct_size(inherit, qgroups, nums)) {
1997                         ret = -EINVAL;
1998                         goto free_inherit;
1999                 }
2000         }
2001
2002         ret = __btrfs_ioctl_snap_create(file, file_mnt_user_ns(file),
2003                                         vol_args->name, vol_args->fd, subvol,
2004                                         readonly, inherit);
2005         if (ret)
2006                 goto free_inherit;
2007 free_inherit:
2008         kfree(inherit);
2009 free_args:
2010         kfree(vol_args);
2011         return ret;
2012 }
2013
2014 static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
2015                                                 void __user *arg)
2016 {
2017         struct inode *inode = file_inode(file);
2018         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2019         struct btrfs_root *root = BTRFS_I(inode)->root;
2020         int ret = 0;
2021         u64 flags = 0;
2022
2023         if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
2024                 return -EINVAL;
2025
2026         down_read(&fs_info->subvol_sem);
2027         if (btrfs_root_readonly(root))
2028                 flags |= BTRFS_SUBVOL_RDONLY;
2029         up_read(&fs_info->subvol_sem);
2030
2031         if (copy_to_user(arg, &flags, sizeof(flags)))
2032                 ret = -EFAULT;
2033
2034         return ret;
2035 }
2036
2037 static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
2038                                               void __user *arg)
2039 {
2040         struct inode *inode = file_inode(file);
2041         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2042         struct btrfs_root *root = BTRFS_I(inode)->root;
2043         struct btrfs_trans_handle *trans;
2044         u64 root_flags;
2045         u64 flags;
2046         int ret = 0;
2047
2048         if (!inode_owner_or_capable(file_mnt_user_ns(file), inode))
2049                 return -EPERM;
2050
2051         ret = mnt_want_write_file(file);
2052         if (ret)
2053                 goto out;
2054
2055         if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2056                 ret = -EINVAL;
2057                 goto out_drop_write;
2058         }
2059
2060         if (copy_from_user(&flags, arg, sizeof(flags))) {
2061                 ret = -EFAULT;
2062                 goto out_drop_write;
2063         }
2064
2065         if (flags & ~BTRFS_SUBVOL_RDONLY) {
2066                 ret = -EOPNOTSUPP;
2067                 goto out_drop_write;
2068         }
2069
2070         down_write(&fs_info->subvol_sem);
2071
2072         /* nothing to do */
2073         if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
2074                 goto out_drop_sem;
2075
2076         root_flags = btrfs_root_flags(&root->root_item);
2077         if (flags & BTRFS_SUBVOL_RDONLY) {
2078                 btrfs_set_root_flags(&root->root_item,
2079                                      root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
2080         } else {
2081                 /*
2082                  * Block RO -> RW transition if this subvolume is involved in
2083                  * send
2084                  */
2085                 spin_lock(&root->root_item_lock);
2086                 if (root->send_in_progress == 0) {
2087                         btrfs_set_root_flags(&root->root_item,
2088                                      root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
2089                         spin_unlock(&root->root_item_lock);
2090                 } else {
2091                         spin_unlock(&root->root_item_lock);
2092                         btrfs_warn(fs_info,
2093                                    "Attempt to set subvolume %llu read-write during send",
2094                                    root->root_key.objectid);
2095                         ret = -EPERM;
2096                         goto out_drop_sem;
2097                 }
2098         }
2099
2100         trans = btrfs_start_transaction(root, 1);
2101         if (IS_ERR(trans)) {
2102                 ret = PTR_ERR(trans);
2103                 goto out_reset;
2104         }
2105
2106         ret = btrfs_update_root(trans, fs_info->tree_root,
2107                                 &root->root_key, &root->root_item);
2108         if (ret < 0) {
2109                 btrfs_end_transaction(trans);
2110                 goto out_reset;
2111         }
2112
2113         ret = btrfs_commit_transaction(trans);
2114
2115 out_reset:
2116         if (ret)
2117                 btrfs_set_root_flags(&root->root_item, root_flags);
2118 out_drop_sem:
2119         up_write(&fs_info->subvol_sem);
2120 out_drop_write:
2121         mnt_drop_write_file(file);
2122 out:
2123         return ret;
2124 }
2125
2126 static noinline int key_in_sk(struct btrfs_key *key,
2127                               struct btrfs_ioctl_search_key *sk)
2128 {
2129         struct btrfs_key test;
2130         int ret;
2131
2132         test.objectid = sk->min_objectid;
2133         test.type = sk->min_type;
2134         test.offset = sk->min_offset;
2135
2136         ret = btrfs_comp_cpu_keys(key, &test);
2137         if (ret < 0)
2138                 return 0;
2139
2140         test.objectid = sk->max_objectid;
2141         test.type = sk->max_type;
2142         test.offset = sk->max_offset;
2143
2144         ret = btrfs_comp_cpu_keys(key, &test);
2145         if (ret > 0)
2146                 return 0;
2147         return 1;
2148 }
2149
2150 static noinline int copy_to_sk(struct btrfs_path *path,
2151                                struct btrfs_key *key,
2152                                struct btrfs_ioctl_search_key *sk,
2153                                size_t *buf_size,
2154                                char __user *ubuf,
2155                                unsigned long *sk_offset,
2156                                int *num_found)
2157 {
2158         u64 found_transid;
2159         struct extent_buffer *leaf;
2160         struct btrfs_ioctl_search_header sh;
2161         struct btrfs_key test;
2162         unsigned long item_off;
2163         unsigned long item_len;
2164         int nritems;
2165         int i;
2166         int slot;
2167         int ret = 0;
2168
2169         leaf = path->nodes[0];
2170         slot = path->slots[0];
2171         nritems = btrfs_header_nritems(leaf);
2172
2173         if (btrfs_header_generation(leaf) > sk->max_transid) {
2174                 i = nritems;
2175                 goto advance_key;
2176         }
2177         found_transid = btrfs_header_generation(leaf);
2178
2179         for (i = slot; i < nritems; i++) {
2180                 item_off = btrfs_item_ptr_offset(leaf, i);
2181                 item_len = btrfs_item_size(leaf, i);
2182
2183                 btrfs_item_key_to_cpu(leaf, key, i);
2184                 if (!key_in_sk(key, sk))
2185                         continue;
2186
2187                 if (sizeof(sh) + item_len > *buf_size) {
2188                         if (*num_found) {
2189                                 ret = 1;
2190                                 goto out;
2191                         }
2192
2193                         /*
2194                          * return one empty item back for v1, which does not
2195                          * handle -EOVERFLOW
2196                          */
2197
2198                         *buf_size = sizeof(sh) + item_len;
2199                         item_len = 0;
2200                         ret = -EOVERFLOW;
2201                 }
2202
2203                 if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2204                         ret = 1;
2205                         goto out;
2206                 }
2207
2208                 sh.objectid = key->objectid;
2209                 sh.offset = key->offset;
2210                 sh.type = key->type;
2211                 sh.len = item_len;
2212                 sh.transid = found_transid;
2213
2214                 /*
2215                  * Copy search result header. If we fault then loop again so we
2216                  * can fault in the pages and -EFAULT there if there's a
2217                  * problem. Otherwise we'll fault and then copy the buffer in
2218                  * properly this next time through
2219                  */
2220                 if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
2221                         ret = 0;
2222                         goto out;
2223                 }
2224
2225                 *sk_offset += sizeof(sh);
2226
2227                 if (item_len) {
2228                         char __user *up = ubuf + *sk_offset;
2229                         /*
2230                          * Copy the item, same behavior as above, but reset the
2231                          * * sk_offset so we copy the full thing again.
2232                          */
2233                         if (read_extent_buffer_to_user_nofault(leaf, up,
2234                                                 item_off, item_len)) {
2235                                 ret = 0;
2236                                 *sk_offset -= sizeof(sh);
2237                                 goto out;
2238                         }
2239
2240                         *sk_offset += item_len;
2241                 }
2242                 (*num_found)++;
2243
2244                 if (ret) /* -EOVERFLOW from above */
2245                         goto out;
2246
2247                 if (*num_found >= sk->nr_items) {
2248                         ret = 1;
2249                         goto out;
2250                 }
2251         }
2252 advance_key:
2253         ret = 0;
2254         test.objectid = sk->max_objectid;
2255         test.type = sk->max_type;
2256         test.offset = sk->max_offset;
2257         if (btrfs_comp_cpu_keys(key, &test) >= 0)
2258                 ret = 1;
2259         else if (key->offset < (u64)-1)
2260                 key->offset++;
2261         else if (key->type < (u8)-1) {
2262                 key->offset = 0;
2263                 key->type++;
2264         } else if (key->objectid < (u64)-1) {
2265                 key->offset = 0;
2266                 key->type = 0;
2267                 key->objectid++;
2268         } else
2269                 ret = 1;
2270 out:
2271         /*
2272          *  0: all items from this leaf copied, continue with next
2273          *  1: * more items can be copied, but unused buffer is too small
2274          *     * all items were found
2275          *     Either way, it will stops the loop which iterates to the next
2276          *     leaf
2277          *  -EOVERFLOW: item was to large for buffer
2278          *  -EFAULT: could not copy extent buffer back to userspace
2279          */
2280         return ret;
2281 }
2282
2283 static noinline int search_ioctl(struct inode *inode,
2284                                  struct btrfs_ioctl_search_key *sk,
2285                                  size_t *buf_size,
2286                                  char __user *ubuf)
2287 {
2288         struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2289         struct btrfs_root *root;
2290         struct btrfs_key key;
2291         struct btrfs_path *path;
2292         int ret;
2293         int num_found = 0;
2294         unsigned long sk_offset = 0;
2295
2296         if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2297                 *buf_size = sizeof(struct btrfs_ioctl_search_header);
2298                 return -EOVERFLOW;
2299         }
2300
2301         path = btrfs_alloc_path();
2302         if (!path)
2303                 return -ENOMEM;
2304
2305         if (sk->tree_id == 0) {
2306                 /* search the root of the inode that was passed */
2307                 root = btrfs_grab_root(BTRFS_I(inode)->root);
2308         } else {
2309                 root = btrfs_get_fs_root(info, sk->tree_id, true);
2310                 if (IS_ERR(root)) {
2311                         btrfs_free_path(path);
2312                         return PTR_ERR(root);
2313                 }
2314         }
2315
2316         key.objectid = sk->min_objectid;
2317         key.type = sk->min_type;
2318         key.offset = sk->min_offset;
2319
2320         while (1) {
2321                 ret = -EFAULT;
2322                 if (fault_in_writeable(ubuf + sk_offset, *buf_size - sk_offset))
2323                         break;
2324
2325                 ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2326                 if (ret != 0) {
2327                         if (ret > 0)
2328                                 ret = 0;
2329                         goto err;
2330                 }
2331                 ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2332                                  &sk_offset, &num_found);
2333                 btrfs_release_path(path);
2334                 if (ret)
2335                         break;
2336
2337         }
2338         if (ret > 0)
2339                 ret = 0;
2340 err:
2341         sk->nr_items = num_found;
2342         btrfs_put_root(root);
2343         btrfs_free_path(path);
2344         return ret;
2345 }
2346
2347 static noinline int btrfs_ioctl_tree_search(struct file *file,
2348                                            void __user *argp)
2349 {
2350         struct btrfs_ioctl_search_args __user *uargs;
2351         struct btrfs_ioctl_search_key sk;
2352         struct inode *inode;
2353         int ret;
2354         size_t buf_size;
2355
2356         if (!capable(CAP_SYS_ADMIN))
2357                 return -EPERM;
2358
2359         uargs = (struct btrfs_ioctl_search_args __user *)argp;
2360
2361         if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2362                 return -EFAULT;
2363
2364         buf_size = sizeof(uargs->buf);
2365
2366         inode = file_inode(file);
2367         ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2368
2369         /*
2370          * In the origin implementation an overflow is handled by returning a
2371          * search header with a len of zero, so reset ret.
2372          */
2373         if (ret == -EOVERFLOW)
2374                 ret = 0;
2375
2376         if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2377                 ret = -EFAULT;
2378         return ret;
2379 }
2380
2381 static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2382                                                void __user *argp)
2383 {
2384         struct btrfs_ioctl_search_args_v2 __user *uarg;
2385         struct btrfs_ioctl_search_args_v2 args;
2386         struct inode *inode;
2387         int ret;
2388         size_t buf_size;
2389         const size_t buf_limit = SZ_16M;
2390
2391         if (!capable(CAP_SYS_ADMIN))
2392                 return -EPERM;
2393
2394         /* copy search header and buffer size */
2395         uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2396         if (copy_from_user(&args, uarg, sizeof(args)))
2397                 return -EFAULT;
2398
2399         buf_size = args.buf_size;
2400
2401         /* limit result size to 16MB */
2402         if (buf_size > buf_limit)
2403                 buf_size = buf_limit;
2404
2405         inode = file_inode(file);
2406         ret = search_ioctl(inode, &args.key, &buf_size,
2407                            (char __user *)(&uarg->buf[0]));
2408         if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2409                 ret = -EFAULT;
2410         else if (ret == -EOVERFLOW &&
2411                 copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2412                 ret = -EFAULT;
2413
2414         return ret;
2415 }
2416
2417 /*
2418  * Search INODE_REFs to identify path name of 'dirid' directory
2419  * in a 'tree_id' tree. and sets path name to 'name'.
2420  */
2421 static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2422                                 u64 tree_id, u64 dirid, char *name)
2423 {
2424         struct btrfs_root *root;
2425         struct btrfs_key key;
2426         char *ptr;
2427         int ret = -1;
2428         int slot;
2429         int len;
2430         int total_len = 0;
2431         struct btrfs_inode_ref *iref;
2432         struct extent_buffer *l;
2433         struct btrfs_path *path;
2434
2435         if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2436                 name[0]='\0';
2437                 return 0;
2438         }
2439
2440         path = btrfs_alloc_path();
2441         if (!path)
2442                 return -ENOMEM;
2443
2444         ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2445
2446         root = btrfs_get_fs_root(info, tree_id, true);
2447         if (IS_ERR(root)) {
2448                 ret = PTR_ERR(root);
2449                 root = NULL;
2450                 goto out;
2451         }
2452
2453         key.objectid = dirid;
2454         key.type = BTRFS_INODE_REF_KEY;
2455         key.offset = (u64)-1;
2456
2457         while (1) {
2458                 ret = btrfs_search_backwards(root, &key, path);
2459                 if (ret < 0)
2460                         goto out;
2461                 else if (ret > 0) {
2462                         ret = -ENOENT;
2463                         goto out;
2464                 }
2465
2466                 l = path->nodes[0];
2467                 slot = path->slots[0];
2468
2469                 iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2470                 len = btrfs_inode_ref_name_len(l, iref);
2471                 ptr -= len + 1;
2472                 total_len += len + 1;
2473                 if (ptr < name) {
2474                         ret = -ENAMETOOLONG;
2475                         goto out;
2476                 }
2477
2478                 *(ptr + len) = '/';
2479                 read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2480
2481                 if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2482                         break;
2483
2484                 btrfs_release_path(path);
2485                 key.objectid = key.offset;
2486                 key.offset = (u64)-1;
2487                 dirid = key.objectid;
2488         }
2489         memmove(name, ptr, total_len);
2490         name[total_len] = '\0';
2491         ret = 0;
2492 out:
2493         btrfs_put_root(root);
2494         btrfs_free_path(path);
2495         return ret;
2496 }
2497
2498 static int btrfs_search_path_in_tree_user(struct user_namespace *mnt_userns,
2499                                 struct inode *inode,
2500                                 struct btrfs_ioctl_ino_lookup_user_args *args)
2501 {
2502         struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2503         struct super_block *sb = inode->i_sb;
2504         struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2505         u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2506         u64 dirid = args->dirid;
2507         unsigned long item_off;
2508         unsigned long item_len;
2509         struct btrfs_inode_ref *iref;
2510         struct btrfs_root_ref *rref;
2511         struct btrfs_root *root = NULL;
2512         struct btrfs_path *path;
2513         struct btrfs_key key, key2;
2514         struct extent_buffer *leaf;
2515         struct inode *temp_inode;
2516         char *ptr;
2517         int slot;
2518         int len;
2519         int total_len = 0;
2520         int ret;
2521
2522         path = btrfs_alloc_path();
2523         if (!path)
2524                 return -ENOMEM;
2525
2526         /*
2527          * If the bottom subvolume does not exist directly under upper_limit,
2528          * construct the path in from the bottom up.
2529          */
2530         if (dirid != upper_limit.objectid) {
2531                 ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2532
2533                 root = btrfs_get_fs_root(fs_info, treeid, true);
2534                 if (IS_ERR(root)) {
2535                         ret = PTR_ERR(root);
2536                         goto out;
2537                 }
2538
2539                 key.objectid = dirid;
2540                 key.type = BTRFS_INODE_REF_KEY;
2541                 key.offset = (u64)-1;
2542                 while (1) {
2543                         ret = btrfs_search_backwards(root, &key, path);
2544                         if (ret < 0)
2545                                 goto out_put;
2546                         else if (ret > 0) {
2547                                 ret = -ENOENT;
2548                                 goto out_put;
2549                         }
2550
2551                         leaf = path->nodes[0];
2552                         slot = path->slots[0];
2553
2554                         iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2555                         len = btrfs_inode_ref_name_len(leaf, iref);
2556                         ptr -= len + 1;
2557                         total_len += len + 1;
2558                         if (ptr < args->path) {
2559                                 ret = -ENAMETOOLONG;
2560                                 goto out_put;
2561                         }
2562
2563                         *(ptr + len) = '/';
2564                         read_extent_buffer(leaf, ptr,
2565                                         (unsigned long)(iref + 1), len);
2566
2567                         /* Check the read+exec permission of this directory */
2568                         ret = btrfs_previous_item(root, path, dirid,
2569                                                   BTRFS_INODE_ITEM_KEY);
2570                         if (ret < 0) {
2571                                 goto out_put;
2572                         } else if (ret > 0) {
2573                                 ret = -ENOENT;
2574                                 goto out_put;
2575                         }
2576
2577                         leaf = path->nodes[0];
2578                         slot = path->slots[0];
2579                         btrfs_item_key_to_cpu(leaf, &key2, slot);
2580                         if (key2.objectid != dirid) {
2581                                 ret = -ENOENT;
2582                                 goto out_put;
2583                         }
2584
2585                         temp_inode = btrfs_iget(sb, key2.objectid, root);
2586                         if (IS_ERR(temp_inode)) {
2587                                 ret = PTR_ERR(temp_inode);
2588                                 goto out_put;
2589                         }
2590                         ret = inode_permission(mnt_userns, temp_inode,
2591                                                MAY_READ | MAY_EXEC);
2592                         iput(temp_inode);
2593                         if (ret) {
2594                                 ret = -EACCES;
2595                                 goto out_put;
2596                         }
2597
2598                         if (key.offset == upper_limit.objectid)
2599                                 break;
2600                         if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2601                                 ret = -EACCES;
2602                                 goto out_put;
2603                         }
2604
2605                         btrfs_release_path(path);
2606                         key.objectid = key.offset;
2607                         key.offset = (u64)-1;
2608                         dirid = key.objectid;
2609                 }
2610
2611                 memmove(args->path, ptr, total_len);
2612                 args->path[total_len] = '\0';
2613                 btrfs_put_root(root);
2614                 root = NULL;
2615                 btrfs_release_path(path);
2616         }
2617
2618         /* Get the bottom subvolume's name from ROOT_REF */
2619         key.objectid = treeid;
2620         key.type = BTRFS_ROOT_REF_KEY;
2621         key.offset = args->treeid;
2622         ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2623         if (ret < 0) {
2624                 goto out;
2625         } else if (ret > 0) {
2626                 ret = -ENOENT;
2627                 goto out;
2628         }
2629
2630         leaf = path->nodes[0];
2631         slot = path->slots[0];
2632         btrfs_item_key_to_cpu(leaf, &key, slot);
2633
2634         item_off = btrfs_item_ptr_offset(leaf, slot);
2635         item_len = btrfs_item_size(leaf, slot);
2636         /* Check if dirid in ROOT_REF corresponds to passed dirid */
2637         rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2638         if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2639                 ret = -EINVAL;
2640                 goto out;
2641         }
2642
2643         /* Copy subvolume's name */
2644         item_off += sizeof(struct btrfs_root_ref);
2645         item_len -= sizeof(struct btrfs_root_ref);
2646         read_extent_buffer(leaf, args->name, item_off, item_len);
2647         args->name[item_len] = 0;
2648
2649 out_put:
2650         btrfs_put_root(root);
2651 out:
2652         btrfs_free_path(path);
2653         return ret;
2654 }
2655
2656 static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2657                                            void __user *argp)
2658 {
2659         struct btrfs_ioctl_ino_lookup_args *args;
2660         struct inode *inode;
2661         int ret = 0;
2662
2663         args = memdup_user(argp, sizeof(*args));
2664         if (IS_ERR(args))
2665                 return PTR_ERR(args);
2666
2667         inode = file_inode(file);
2668
2669         /*
2670          * Unprivileged query to obtain the containing subvolume root id. The
2671          * path is reset so it's consistent with btrfs_search_path_in_tree.
2672          */
2673         if (args->treeid == 0)
2674                 args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2675
2676         if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2677                 args->name[0] = 0;
2678                 goto out;
2679         }
2680
2681         if (!capable(CAP_SYS_ADMIN)) {
2682                 ret = -EPERM;
2683                 goto out;
2684         }
2685
2686         ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2687                                         args->treeid, args->objectid,
2688                                         args->name);
2689
2690 out:
2691         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2692                 ret = -EFAULT;
2693
2694         kfree(args);
2695         return ret;
2696 }
2697
2698 /*
2699  * Version of ino_lookup ioctl (unprivileged)
2700  *
2701  * The main differences from ino_lookup ioctl are:
2702  *
2703  *   1. Read + Exec permission will be checked using inode_permission() during
2704  *      path construction. -EACCES will be returned in case of failure.
2705  *   2. Path construction will be stopped at the inode number which corresponds
2706  *      to the fd with which this ioctl is called. If constructed path does not
2707  *      exist under fd's inode, -EACCES will be returned.
2708  *   3. The name of bottom subvolume is also searched and filled.
2709  */
2710 static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2711 {
2712         struct btrfs_ioctl_ino_lookup_user_args *args;
2713         struct inode *inode;
2714         int ret;
2715
2716         args = memdup_user(argp, sizeof(*args));
2717         if (IS_ERR(args))
2718                 return PTR_ERR(args);
2719
2720         inode = file_inode(file);
2721
2722         if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2723             BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2724                 /*
2725                  * The subvolume does not exist under fd with which this is
2726                  * called
2727                  */
2728                 kfree(args);
2729                 return -EACCES;
2730         }
2731
2732         ret = btrfs_search_path_in_tree_user(file_mnt_user_ns(file), inode, args);
2733
2734         if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2735                 ret = -EFAULT;
2736
2737         kfree(args);
2738         return ret;
2739 }
2740
2741 /* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2742 static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2743 {
2744         struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2745         struct btrfs_fs_info *fs_info;
2746         struct btrfs_root *root;
2747         struct btrfs_path *path;
2748         struct btrfs_key key;
2749         struct btrfs_root_item *root_item;
2750         struct btrfs_root_ref *rref;
2751         struct extent_buffer *leaf;
2752         unsigned long item_off;
2753         unsigned long item_len;
2754         struct inode *inode;
2755         int slot;
2756         int ret = 0;
2757
2758         path = btrfs_alloc_path();
2759         if (!path)
2760                 return -ENOMEM;
2761
2762         subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2763         if (!subvol_info) {
2764                 btrfs_free_path(path);
2765                 return -ENOMEM;
2766         }
2767
2768         inode = file_inode(file);
2769         fs_info = BTRFS_I(inode)->root->fs_info;
2770
2771         /* Get root_item of inode's subvolume */
2772         key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2773         root = btrfs_get_fs_root(fs_info, key.objectid, true);
2774         if (IS_ERR(root)) {
2775                 ret = PTR_ERR(root);
2776                 goto out_free;
2777         }
2778         root_item = &root->root_item;
2779
2780         subvol_info->treeid = key.objectid;
2781
2782         subvol_info->generation = btrfs_root_generation(root_item);
2783         subvol_info->flags = btrfs_root_flags(root_item);
2784
2785         memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2786         memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2787                                                     BTRFS_UUID_SIZE);
2788         memcpy(subvol_info->received_uuid, root_item->received_uuid,
2789                                                     BTRFS_UUID_SIZE);
2790
2791         subvol_info->ctransid = btrfs_root_ctransid(root_item);
2792         subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2793         subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2794
2795         subvol_info->otransid = btrfs_root_otransid(root_item);
2796         subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2797         subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2798
2799         subvol_info->stransid = btrfs_root_stransid(root_item);
2800         subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2801         subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2802
2803         subvol_info->rtransid = btrfs_root_rtransid(root_item);
2804         subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2805         subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2806
2807         if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2808                 /* Search root tree for ROOT_BACKREF of this subvolume */
2809                 key.type = BTRFS_ROOT_BACKREF_KEY;
2810                 key.offset = 0;
2811                 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2812                 if (ret < 0) {
2813                         goto out;
2814                 } else if (path->slots[0] >=
2815                            btrfs_header_nritems(path->nodes[0])) {
2816                         ret = btrfs_next_leaf(fs_info->tree_root, path);
2817                         if (ret < 0) {
2818                                 goto out;
2819                         } else if (ret > 0) {
2820                                 ret = -EUCLEAN;
2821                                 goto out;
2822                         }
2823                 }
2824
2825                 leaf = path->nodes[0];
2826                 slot = path->slots[0];
2827                 btrfs_item_key_to_cpu(leaf, &key, slot);
2828                 if (key.objectid == subvol_info->treeid &&
2829                     key.type == BTRFS_ROOT_BACKREF_KEY) {
2830                         subvol_info->parent_id = key.offset;
2831
2832                         rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2833                         subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2834
2835                         item_off = btrfs_item_ptr_offset(leaf, slot)
2836                                         + sizeof(struct btrfs_root_ref);
2837                         item_len = btrfs_item_size(leaf, slot)
2838                                         - sizeof(struct btrfs_root_ref);
2839                         read_extent_buffer(leaf, subvol_info->name,
2840                                            item_off, item_len);
2841                 } else {
2842                         ret = -ENOENT;
2843                         goto out;
2844                 }
2845         }
2846
2847         if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2848                 ret = -EFAULT;
2849
2850 out:
2851         btrfs_put_root(root);
2852 out_free:
2853         btrfs_free_path(path);
2854         kfree(subvol_info);
2855         return ret;
2856 }
2857
2858 /*
2859  * Return ROOT_REF information of the subvolume containing this inode
2860  * except the subvolume name.
2861  */
2862 static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2863 {
2864         struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2865         struct btrfs_root_ref *rref;
2866         struct btrfs_root *root;
2867         struct btrfs_path *path;
2868         struct btrfs_key key;
2869         struct extent_buffer *leaf;
2870         struct inode *inode;
2871         u64 objectid;
2872         int slot;
2873         int ret;
2874         u8 found;
2875
2876         path = btrfs_alloc_path();
2877         if (!path)
2878                 return -ENOMEM;
2879
2880         rootrefs = memdup_user(argp, sizeof(*rootrefs));
2881         if (IS_ERR(rootrefs)) {
2882                 btrfs_free_path(path);
2883                 return PTR_ERR(rootrefs);
2884         }
2885
2886         inode = file_inode(file);
2887         root = BTRFS_I(inode)->root->fs_info->tree_root;
2888         objectid = BTRFS_I(inode)->root->root_key.objectid;
2889
2890         key.objectid = objectid;
2891         key.type = BTRFS_ROOT_REF_KEY;
2892         key.offset = rootrefs->min_treeid;
2893         found = 0;
2894
2895         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2896         if (ret < 0) {
2897                 goto out;
2898         } else if (path->slots[0] >=
2899                    btrfs_header_nritems(path->nodes[0])) {
2900                 ret = btrfs_next_leaf(root, path);
2901                 if (ret < 0) {
2902                         goto out;
2903                 } else if (ret > 0) {
2904                         ret = -EUCLEAN;
2905                         goto out;
2906                 }
2907         }
2908         while (1) {
2909                 leaf = path->nodes[0];
2910                 slot = path->slots[0];
2911
2912                 btrfs_item_key_to_cpu(leaf, &key, slot);
2913                 if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2914                         ret = 0;
2915                         goto out;
2916                 }
2917
2918                 if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2919                         ret = -EOVERFLOW;
2920                         goto out;
2921                 }
2922
2923                 rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2924                 rootrefs->rootref[found].treeid = key.offset;
2925                 rootrefs->rootref[found].dirid =
2926                                   btrfs_root_ref_dirid(leaf, rref);
2927                 found++;
2928
2929                 ret = btrfs_next_item(root, path);
2930                 if (ret < 0) {
2931                         goto out;
2932                 } else if (ret > 0) {
2933                         ret = -EUCLEAN;
2934                         goto out;
2935                 }
2936         }
2937
2938 out:
2939         if (!ret || ret == -EOVERFLOW) {
2940                 rootrefs->num_items = found;
2941                 /* update min_treeid for next search */
2942                 if (found)
2943                         rootrefs->min_treeid =
2944                                 rootrefs->rootref[found - 1].treeid + 1;
2945                 if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2946                         ret = -EFAULT;
2947         }
2948
2949         kfree(rootrefs);
2950         btrfs_free_path(path);
2951
2952         return ret;
2953 }
2954
2955 static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2956                                              void __user *arg,
2957                                              bool destroy_v2)
2958 {
2959         struct dentry *parent = file->f_path.dentry;
2960         struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2961         struct dentry *dentry;
2962         struct inode *dir = d_inode(parent);
2963         struct inode *inode;
2964         struct btrfs_root *root = BTRFS_I(dir)->root;
2965         struct btrfs_root *dest = NULL;
2966         struct btrfs_ioctl_vol_args *vol_args = NULL;
2967         struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
2968         struct user_namespace *mnt_userns = file_mnt_user_ns(file);
2969         char *subvol_name, *subvol_name_ptr = NULL;
2970         int subvol_namelen;
2971         int err = 0;
2972         bool destroy_parent = false;
2973
2974         if (destroy_v2) {
2975                 vol_args2 = memdup_user(arg, sizeof(*vol_args2));
2976                 if (IS_ERR(vol_args2))
2977                         return PTR_ERR(vol_args2);
2978
2979                 if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
2980                         err = -EOPNOTSUPP;
2981                         goto out;
2982                 }
2983
2984                 /*
2985                  * If SPEC_BY_ID is not set, we are looking for the subvolume by
2986                  * name, same as v1 currently does.
2987                  */
2988                 if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
2989                         vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
2990                         subvol_name = vol_args2->name;
2991
2992                         err = mnt_want_write_file(file);
2993                         if (err)
2994                                 goto out;
2995                 } else {
2996                         struct inode *old_dir;
2997
2998                         if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
2999                                 err = -EINVAL;
3000                                 goto out;
3001                         }
3002
3003                         err = mnt_want_write_file(file);
3004                         if (err)
3005                                 goto out;
3006
3007                         dentry = btrfs_get_dentry(fs_info->sb,
3008                                         BTRFS_FIRST_FREE_OBJECTID,
3009                                         vol_args2->subvolid, 0, 0);
3010                         if (IS_ERR(dentry)) {
3011                                 err = PTR_ERR(dentry);
3012                                 goto out_drop_write;
3013                         }
3014
3015                         /*
3016                          * Change the default parent since the subvolume being
3017                          * deleted can be outside of the current mount point.
3018                          */
3019                         parent = btrfs_get_parent(dentry);
3020
3021                         /*
3022                          * At this point dentry->d_name can point to '/' if the
3023                          * subvolume we want to destroy is outsite of the
3024                          * current mount point, so we need to release the
3025                          * current dentry and execute the lookup to return a new
3026                          * one with ->d_name pointing to the
3027                          * <mount point>/subvol_name.
3028                          */
3029                         dput(dentry);
3030                         if (IS_ERR(parent)) {
3031                                 err = PTR_ERR(parent);
3032                                 goto out_drop_write;
3033                         }
3034                         old_dir = dir;
3035                         dir = d_inode(parent);
3036
3037                         /*
3038                          * If v2 was used with SPEC_BY_ID, a new parent was
3039                          * allocated since the subvolume can be outside of the
3040                          * current mount point. Later on we need to release this
3041                          * new parent dentry.
3042                          */
3043                         destroy_parent = true;
3044
3045                         /*
3046                          * On idmapped mounts, deletion via subvolid is
3047                          * restricted to subvolumes that are immediate
3048                          * ancestors of the inode referenced by the file
3049                          * descriptor in the ioctl. Otherwise the idmapping
3050                          * could potentially be abused to delete subvolumes
3051                          * anywhere in the filesystem the user wouldn't be able
3052                          * to delete without an idmapped mount.
3053                          */
3054                         if (old_dir != dir && mnt_userns != &init_user_ns) {
3055                                 err = -EOPNOTSUPP;
3056                                 goto free_parent;
3057                         }
3058
3059                         subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
3060                                                 fs_info, vol_args2->subvolid);
3061                         if (IS_ERR(subvol_name_ptr)) {
3062                                 err = PTR_ERR(subvol_name_ptr);
3063                                 goto free_parent;
3064                         }
3065                         /* subvol_name_ptr is already nul terminated */
3066                         subvol_name = (char *)kbasename(subvol_name_ptr);
3067                 }
3068         } else {
3069                 vol_args = memdup_user(arg, sizeof(*vol_args));
3070                 if (IS_ERR(vol_args))
3071                         return PTR_ERR(vol_args);
3072
3073                 vol_args->name[BTRFS_PATH_NAME_MAX] = 0;
3074                 subvol_name = vol_args->name;
3075
3076                 err = mnt_want_write_file(file);
3077                 if (err)
3078                         goto out;
3079         }
3080
3081         subvol_namelen = strlen(subvol_name);
3082
3083         if (strchr(subvol_name, '/') ||
3084             strncmp(subvol_name, "..", subvol_namelen) == 0) {
3085                 err = -EINVAL;
3086                 goto free_subvol_name;
3087         }
3088
3089         if (!S_ISDIR(dir->i_mode)) {
3090                 err = -ENOTDIR;
3091                 goto free_subvol_name;
3092         }
3093
3094         err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
3095         if (err == -EINTR)
3096                 goto free_subvol_name;
3097         dentry = lookup_one(mnt_userns, subvol_name, parent, subvol_namelen);
3098         if (IS_ERR(dentry)) {
3099                 err = PTR_ERR(dentry);
3100                 goto out_unlock_dir;
3101         }
3102
3103         if (d_really_is_negative(dentry)) {
3104                 err = -ENOENT;
3105                 goto out_dput;
3106         }
3107
3108         inode = d_inode(dentry);
3109         dest = BTRFS_I(inode)->root;
3110         if (!capable(CAP_SYS_ADMIN)) {
3111                 /*
3112                  * Regular user.  Only allow this with a special mount
3113                  * option, when the user has write+exec access to the
3114                  * subvol root, and when rmdir(2) would have been
3115                  * allowed.
3116                  *
3117                  * Note that this is _not_ check that the subvol is
3118                  * empty or doesn't contain data that we wouldn't
3119                  * otherwise be able to delete.
3120                  *
3121                  * Users who want to delete empty subvols should try
3122                  * rmdir(2).
3123                  */
3124                 err = -EPERM;
3125                 if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
3126                         goto out_dput;
3127
3128                 /*
3129                  * Do not allow deletion if the parent dir is the same
3130                  * as the dir to be deleted.  That means the ioctl
3131                  * must be called on the dentry referencing the root
3132                  * of the subvol, not a random directory contained
3133                  * within it.
3134                  */
3135                 err = -EINVAL;
3136                 if (root == dest)
3137                         goto out_dput;
3138
3139                 err = inode_permission(mnt_userns, inode, MAY_WRITE | MAY_EXEC);
3140                 if (err)
3141                         goto out_dput;
3142         }
3143
3144         /* check if subvolume may be deleted by a user */
3145         err = btrfs_may_delete(mnt_userns, dir, dentry, 1);
3146         if (err)
3147                 goto out_dput;
3148
3149         if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
3150                 err = -EINVAL;
3151                 goto out_dput;
3152         }
3153
3154         btrfs_inode_lock(inode, 0);
3155         err = btrfs_delete_subvolume(dir, dentry);
3156         btrfs_inode_unlock(inode, 0);
3157         if (!err)
3158                 d_delete_notify(dir, dentry);
3159
3160 out_dput:
3161         dput(dentry);
3162 out_unlock_dir:
3163         btrfs_inode_unlock(dir, 0);
3164 free_subvol_name:
3165         kfree(subvol_name_ptr);
3166 free_parent:
3167         if (destroy_parent)
3168                 dput(parent);
3169 out_drop_write:
3170         mnt_drop_write_file(file);
3171 out:
3172         kfree(vol_args2);
3173         kfree(vol_args);
3174         return err;
3175 }
3176
3177 static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
3178 {
3179         struct inode *inode = file_inode(file);
3180         struct btrfs_root *root = BTRFS_I(inode)->root;
3181         struct btrfs_ioctl_defrag_range_args range = {0};
3182         int ret;
3183
3184         ret = mnt_want_write_file(file);
3185         if (ret)
3186                 return ret;
3187
3188         if (btrfs_root_readonly(root)) {
3189                 ret = -EROFS;
3190                 goto out;
3191         }
3192
3193         switch (inode->i_mode & S_IFMT) {
3194         case S_IFDIR:
3195                 if (!capable(CAP_SYS_ADMIN)) {
3196                         ret = -EPERM;
3197                         goto out;
3198                 }
3199                 ret = btrfs_defrag_root(root);
3200                 break;
3201         case S_IFREG:
3202                 /*
3203                  * Note that this does not check the file descriptor for write
3204                  * access. This prevents defragmenting executables that are
3205                  * running and allows defrag on files open in read-only mode.
3206                  */
3207                 if (!capable(CAP_SYS_ADMIN) &&
3208                     inode_permission(&init_user_ns, inode, MAY_WRITE)) {
3209                         ret = -EPERM;
3210                         goto out;
3211                 }
3212
3213                 if (argp) {
3214                         if (copy_from_user(&range, argp, sizeof(range))) {
3215                                 ret = -EFAULT;
3216                                 goto out;
3217                         }
3218                         /* compression requires us to start the IO */
3219                         if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
3220                                 range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
3221                                 range.extent_thresh = (u32)-1;
3222                         }
3223                 } else {
3224                         /* the rest are all set to zero by kzalloc */
3225                         range.len = (u64)-1;
3226                 }
3227                 ret = btrfs_defrag_file(file_inode(file), &file->f_ra,
3228                                         &range, BTRFS_OLDEST_GENERATION, 0);
3229                 if (ret > 0)
3230                         ret = 0;
3231                 break;
3232         default:
3233                 ret = -EINVAL;
3234         }
3235 out:
3236         mnt_drop_write_file(file);
3237         return ret;
3238 }
3239
3240 static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
3241 {
3242         struct btrfs_ioctl_vol_args *vol_args;
3243         bool restore_op = false;
3244         int ret;
3245
3246         if (!capable(CAP_SYS_ADMIN))
3247                 return -EPERM;
3248
3249         if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) {
3250                 if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD))
3251                         return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3252
3253                 /*
3254                  * We can do the device add because we have a paused balanced,
3255                  * change the exclusive op type and remember we should bring
3256                  * back the paused balance
3257                  */
3258                 fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD;
3259                 btrfs_exclop_start_unlock(fs_info);
3260                 restore_op = true;
3261         }
3262
3263         vol_args = memdup_user(arg, sizeof(*vol_args));
3264         if (IS_ERR(vol_args)) {
3265                 ret = PTR_ERR(vol_args);
3266                 goto out;
3267         }
3268
3269         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3270         ret = btrfs_init_new_device(fs_info, vol_args->name);
3271
3272         if (!ret)
3273                 btrfs_info(fs_info, "disk added %s", vol_args->name);
3274
3275         kfree(vol_args);
3276 out:
3277         if (restore_op)
3278                 btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
3279         else
3280                 btrfs_exclop_finish(fs_info);
3281         return ret;
3282 }
3283
3284 static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3285 {
3286         BTRFS_DEV_LOOKUP_ARGS(args);
3287         struct inode *inode = file_inode(file);
3288         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3289         struct btrfs_ioctl_vol_args_v2 *vol_args;
3290         struct block_device *bdev = NULL;
3291         fmode_t mode;
3292         int ret;
3293         bool cancel = false;
3294
3295         if (!capable(CAP_SYS_ADMIN))
3296                 return -EPERM;
3297
3298         vol_args = memdup_user(arg, sizeof(*vol_args));
3299         if (IS_ERR(vol_args))
3300                 return PTR_ERR(vol_args);
3301
3302         if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
3303                 ret = -EOPNOTSUPP;
3304                 goto out;
3305         }
3306
3307         vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3308         if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
3309                 args.devid = vol_args->devid;
3310         } else if (!strcmp("cancel", vol_args->name)) {
3311                 cancel = true;
3312         } else {
3313                 ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
3314                 if (ret)
3315                         goto out;
3316         }
3317
3318         ret = mnt_want_write_file(file);
3319         if (ret)
3320                 goto out;
3321
3322         ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
3323                                            cancel);
3324         if (ret)
3325                 goto err_drop;
3326
3327         /* Exclusive operation is now claimed */
3328         ret = btrfs_rm_device(fs_info, &args, &bdev, &mode);
3329
3330         btrfs_exclop_finish(fs_info);
3331
3332         if (!ret) {
3333                 if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3334                         btrfs_info(fs_info, "device deleted: id %llu",
3335                                         vol_args->devid);
3336                 else
3337                         btrfs_info(fs_info, "device deleted: %s",
3338                                         vol_args->name);
3339         }
3340 err_drop:
3341         mnt_drop_write_file(file);
3342         if (bdev)
3343                 blkdev_put(bdev, mode);
3344 out:
3345         btrfs_put_dev_args_from_path(&args);
3346         kfree(vol_args);
3347         return ret;
3348 }
3349
3350 static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3351 {
3352         BTRFS_DEV_LOOKUP_ARGS(args);
3353         struct inode *inode = file_inode(file);
3354         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3355         struct btrfs_ioctl_vol_args *vol_args;
3356         struct block_device *bdev = NULL;
3357         fmode_t mode;
3358         int ret;
3359         bool cancel = false;
3360
3361         if (!capable(CAP_SYS_ADMIN))
3362                 return -EPERM;
3363
3364         vol_args = memdup_user(arg, sizeof(*vol_args));
3365         if (IS_ERR(vol_args))
3366                 return PTR_ERR(vol_args);
3367
3368         vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3369         if (!strcmp("cancel", vol_args->name)) {
3370                 cancel = true;
3371         } else {
3372                 ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
3373                 if (ret)
3374                         goto out;
3375         }
3376
3377         ret = mnt_want_write_file(file);
3378         if (ret)
3379                 goto out;
3380
3381         ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
3382                                            cancel);
3383         if (ret == 0) {
3384                 ret = btrfs_rm_device(fs_info, &args, &bdev, &mode);
3385                 if (!ret)
3386                         btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3387                 btrfs_exclop_finish(fs_info);
3388         }
3389
3390         mnt_drop_write_file(file);
3391         if (bdev)
3392                 blkdev_put(bdev, mode);
3393 out:
3394         btrfs_put_dev_args_from_path(&args);
3395         kfree(vol_args);
3396         return ret;
3397 }
3398
3399 static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3400                                 void __user *arg)
3401 {
3402         struct btrfs_ioctl_fs_info_args *fi_args;
3403         struct btrfs_device *device;
3404         struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3405         u64 flags_in;
3406         int ret = 0;
3407
3408         fi_args = memdup_user(arg, sizeof(*fi_args));
3409         if (IS_ERR(fi_args))
3410                 return PTR_ERR(fi_args);
3411
3412         flags_in = fi_args->flags;
3413         memset(fi_args, 0, sizeof(*fi_args));
3414
3415         rcu_read_lock();
3416         fi_args->num_devices = fs_devices->num_devices;
3417
3418         list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3419                 if (device->devid > fi_args->max_id)
3420                         fi_args->max_id = device->devid;
3421         }
3422         rcu_read_unlock();
3423
3424         memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
3425         fi_args->nodesize = fs_info->nodesize;
3426         fi_args->sectorsize = fs_info->sectorsize;
3427         fi_args->clone_alignment = fs_info->sectorsize;
3428
3429         if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
3430                 fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
3431                 fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
3432                 fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
3433         }
3434
3435         if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
3436                 fi_args->generation = fs_info->generation;
3437                 fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
3438         }
3439
3440         if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
3441                 memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
3442                        sizeof(fi_args->metadata_uuid));
3443                 fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
3444         }
3445
3446         if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3447                 ret = -EFAULT;
3448
3449         kfree(fi_args);
3450         return ret;
3451 }
3452
3453 static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3454                                  void __user *arg)
3455 {
3456         BTRFS_DEV_LOOKUP_ARGS(args);
3457         struct btrfs_ioctl_dev_info_args *di_args;
3458         struct btrfs_device *dev;
3459         int ret = 0;
3460
3461         di_args = memdup_user(arg, sizeof(*di_args));
3462         if (IS_ERR(di_args))
3463                 return PTR_ERR(di_args);
3464
3465         args.devid = di_args->devid;
3466         if (!btrfs_is_empty_uuid(di_args->uuid))
3467                 args.uuid = di_args->uuid;
3468
3469         rcu_read_lock();
3470         dev = btrfs_find_device(fs_info->fs_devices, &args);
3471         if (!dev) {
3472                 ret = -ENODEV;
3473                 goto out;
3474         }
3475
3476         di_args->devid = dev->devid;
3477         di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3478         di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3479         memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3480         if (dev->name) {
3481                 strncpy(di_args->path, rcu_str_deref(dev->name),
3482                                 sizeof(di_args->path) - 1);
3483                 di_args->path[sizeof(di_args->path) - 1] = 0;
3484         } else {
3485                 di_args->path[0] = '\0';
3486         }
3487
3488 out:
3489         rcu_read_unlock();
3490         if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3491                 ret = -EFAULT;
3492
3493         kfree(di_args);
3494         return ret;
3495 }
3496
3497 static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3498 {
3499         struct inode *inode = file_inode(file);
3500         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3501         struct btrfs_root *root = BTRFS_I(inode)->root;
3502         struct btrfs_root *new_root;
3503         struct btrfs_dir_item *di;
3504         struct btrfs_trans_handle *trans;
3505         struct btrfs_path *path = NULL;
3506         struct btrfs_disk_key disk_key;
3507         u64 objectid = 0;
3508         u64 dir_id;
3509         int ret;
3510
3511         if (!capable(CAP_SYS_ADMIN))
3512                 return -EPERM;
3513
3514         ret = mnt_want_write_file(file);
3515         if (ret)
3516                 return ret;
3517
3518         if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3519                 ret = -EFAULT;
3520                 goto out;
3521         }
3522
3523         if (!objectid)
3524                 objectid = BTRFS_FS_TREE_OBJECTID;
3525
3526         new_root = btrfs_get_fs_root(fs_info, objectid, true);
3527         if (IS_ERR(new_root)) {
3528                 ret = PTR_ERR(new_root);
3529                 goto out;
3530         }
3531         if (!is_fstree(new_root->root_key.objectid)) {
3532                 ret = -ENOENT;
3533                 goto out_free;
3534         }
3535
3536         path = btrfs_alloc_path();
3537         if (!path) {
3538                 ret = -ENOMEM;
3539                 goto out_free;
3540         }
3541
3542         trans = btrfs_start_transaction(root, 1);
3543         if (IS_ERR(trans)) {
3544                 ret = PTR_ERR(trans);
3545                 goto out_free;
3546         }
3547
3548         dir_id = btrfs_super_root_dir(fs_info->super_copy);
3549         di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
3550                                    dir_id, "default", 7, 1);
3551         if (IS_ERR_OR_NULL(di)) {
3552                 btrfs_release_path(path);
3553                 btrfs_end_transaction(trans);
3554                 btrfs_err(fs_info,
3555                           "Umm, you don't have the default diritem, this isn't going to work");
3556                 ret = -ENOENT;
3557                 goto out_free;
3558         }
3559
3560         btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3561         btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3562         btrfs_mark_buffer_dirty(path->nodes[0]);
3563         btrfs_release_path(path);
3564
3565         btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
3566         btrfs_end_transaction(trans);
3567 out_free:
3568         btrfs_put_root(new_root);
3569         btrfs_free_path(path);
3570 out:
3571         mnt_drop_write_file(file);
3572         return ret;
3573 }
3574
3575 static void get_block_group_info(struct list_head *groups_list,
3576                                  struct btrfs_ioctl_space_info *space)
3577 {
3578         struct btrfs_block_group *block_group;
3579
3580         space->total_bytes = 0;
3581         space->used_bytes = 0;
3582         space->flags = 0;
3583         list_for_each_entry(block_group, groups_list, list) {
3584                 space->flags = block_group->flags;
3585                 space->total_bytes += block_group->length;
3586                 space->used_bytes += block_group->used;
3587         }
3588 }
3589
3590 static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
3591                                    void __user *arg)
3592 {
3593         struct btrfs_ioctl_space_args space_args;
3594         struct btrfs_ioctl_space_info space;
3595         struct btrfs_ioctl_space_info *dest;
3596         struct btrfs_ioctl_space_info *dest_orig;
3597         struct btrfs_ioctl_space_info __user *user_dest;
3598         struct btrfs_space_info *info;
3599         static const u64 types[] = {
3600                 BTRFS_BLOCK_GROUP_DATA,
3601                 BTRFS_BLOCK_GROUP_SYSTEM,
3602                 BTRFS_BLOCK_GROUP_METADATA,
3603                 BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
3604         };
3605         int num_types = 4;
3606         int alloc_size;
3607         int ret = 0;
3608         u64 slot_count = 0;
3609         int i, c;
3610
3611         if (copy_from_user(&space_args,
3612                            (struct btrfs_ioctl_space_args __user *)arg,
3613                            sizeof(space_args)))
3614                 return -EFAULT;
3615
3616         for (i = 0; i < num_types; i++) {
3617                 struct btrfs_space_info *tmp;
3618
3619                 info = NULL;
3620                 list_for_each_entry(tmp, &fs_info->space_info, list) {
3621                         if (tmp->flags == types[i]) {
3622                                 info = tmp;
3623                                 break;
3624                         }
3625                 }
3626
3627                 if (!info)
3628                         continue;
3629
3630                 down_read(&info->groups_sem);
3631                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3632                         if (!list_empty(&info->block_groups[c]))
3633                                 slot_count++;
3634                 }
3635                 up_read(&info->groups_sem);
3636         }
3637
3638         /*
3639          * Global block reserve, exported as a space_info
3640          */
3641         slot_count++;
3642
3643         /* space_slots == 0 means they are asking for a count */
3644         if (space_args.space_slots == 0) {
3645                 space_args.total_spaces = slot_count;
3646                 goto out;
3647         }
3648
3649         slot_count = min_t(u64, space_args.space_slots, slot_count);
3650
3651         alloc_size = sizeof(*dest) * slot_count;
3652
3653         /* we generally have at most 6 or so space infos, one for each raid
3654          * level.  So, a whole page should be more than enough for everyone
3655          */
3656         if (alloc_size > PAGE_SIZE)
3657                 return -ENOMEM;
3658
3659         space_args.total_spaces = 0;
3660         dest = kmalloc(alloc_size, GFP_KERNEL);
3661         if (!dest)
3662                 return -ENOMEM;
3663         dest_orig = dest;
3664
3665         /* now we have a buffer to copy into */
3666         for (i = 0; i < num_types; i++) {
3667                 struct btrfs_space_info *tmp;
3668
3669                 if (!slot_count)
3670                         break;
3671
3672                 info = NULL;
3673                 list_for_each_entry(tmp, &fs_info->space_info, list) {
3674                         if (tmp->flags == types[i]) {
3675                                 info = tmp;
3676                                 break;
3677                         }
3678                 }
3679
3680                 if (!info)
3681                         continue;
3682                 down_read(&info->groups_sem);
3683                 for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3684                         if (!list_empty(&info->block_groups[c])) {
3685                                 get_block_group_info(&info->block_groups[c],
3686                                                      &space);
3687                                 memcpy(dest, &space, sizeof(space));
3688                                 dest++;
3689                                 space_args.total_spaces++;
3690                                 slot_count--;
3691                         }
3692                         if (!slot_count)
3693                                 break;
3694                 }
3695                 up_read(&info->groups_sem);
3696         }
3697
3698         /*
3699          * Add global block reserve
3700          */
3701         if (slot_count) {
3702                 struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3703
3704                 spin_lock(&block_rsv->lock);
3705                 space.total_bytes = block_rsv->size;
3706                 space.used_bytes = block_rsv->size - block_rsv->reserved;
3707                 spin_unlock(&block_rsv->lock);
3708                 space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3709                 memcpy(dest, &space, sizeof(space));
3710                 space_args.total_spaces++;
3711         }
3712
3713         user_dest = (struct btrfs_ioctl_space_info __user *)
3714                 (arg + sizeof(struct btrfs_ioctl_space_args));
3715
3716         if (copy_to_user(user_dest, dest_orig, alloc_size))
3717                 ret = -EFAULT;
3718
3719         kfree(dest_orig);
3720 out:
3721         if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3722                 ret = -EFAULT;
3723
3724         return ret;
3725 }
3726
3727 static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3728                                             void __user *argp)
3729 {
3730         struct btrfs_trans_handle *trans;
3731         u64 transid;
3732
3733         trans = btrfs_attach_transaction_barrier(root);
3734         if (IS_ERR(trans)) {
3735                 if (PTR_ERR(trans) != -ENOENT)
3736                         return PTR_ERR(trans);
3737
3738                 /* No running transaction, don't bother */
3739                 transid = root->fs_info->last_trans_committed;
3740                 goto out;
3741         }
3742         transid = trans->transid;
3743         btrfs_commit_transaction_async(trans);
3744 out:
3745         if (argp)
3746                 if (copy_to_user(argp, &transid, sizeof(transid)))
3747                         return -EFAULT;
3748         return 0;
3749 }
3750
3751 static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
3752                                            void __user *argp)
3753 {
3754         u64 transid;
3755
3756         if (argp) {
3757                 if (copy_from_user(&transid, argp, sizeof(transid)))
3758                         return -EFAULT;
3759         } else {
3760                 transid = 0;  /* current trans */
3761         }
3762         return btrfs_wait_for_commit(fs_info, transid);
3763 }
3764
3765 static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3766 {
3767         struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
3768         struct btrfs_ioctl_scrub_args *sa;
3769         int ret;
3770
3771         if (!capable(CAP_SYS_ADMIN))
3772                 return -EPERM;
3773
3774         sa = memdup_user(arg, sizeof(*sa));
3775         if (IS_ERR(sa))
3776                 return PTR_ERR(sa);
3777
3778         if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3779                 ret = mnt_want_write_file(file);
3780                 if (ret)
3781                         goto out;
3782         }
3783
3784         ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
3785                               &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3786                               0);
3787
3788         /*
3789          * Copy scrub args to user space even if btrfs_scrub_dev() returned an
3790          * error. This is important as it allows user space to know how much
3791          * progress scrub has done. For example, if scrub is canceled we get
3792          * -ECANCELED from btrfs_scrub_dev() and return that error back to user
3793          * space. Later user space can inspect the progress from the structure
3794          * btrfs_ioctl_scrub_args and resume scrub from where it left off
3795          * previously (btrfs-progs does this).
3796          * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
3797          * then return -EFAULT to signal the structure was not copied or it may
3798          * be corrupt and unreliable due to a partial copy.
3799          */
3800         if (copy_to_user(arg, sa, sizeof(*sa)))
3801                 ret = -EFAULT;
3802
3803         if (!(sa->flags & BTRFS_SCRUB_READONLY))
3804                 mnt_drop_write_file(file);
3805 out:
3806         kfree(sa);
3807         return ret;
3808 }
3809
3810 static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
3811 {
3812         if (!capable(CAP_SYS_ADMIN))
3813                 return -EPERM;
3814
3815         return btrfs_scrub_cancel(fs_info);
3816 }
3817
3818 static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
3819                                        void __user *arg)
3820 {
3821         struct btrfs_ioctl_scrub_args *sa;
3822         int ret;
3823
3824         if (!capable(CAP_SYS_ADMIN))
3825                 return -EPERM;
3826
3827         sa = memdup_user(arg, sizeof(*sa));
3828         if (IS_ERR(sa))
3829                 return PTR_ERR(sa);
3830
3831         ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
3832
3833         if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3834                 ret = -EFAULT;
3835
3836         kfree(sa);
3837         return ret;
3838 }
3839
3840 static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
3841                                       void __user *arg)
3842 {
3843         struct btrfs_ioctl_get_dev_stats *sa;
3844         int ret;
3845
3846         sa = memdup_user(arg, sizeof(*sa));
3847         if (IS_ERR(sa))
3848                 return PTR_ERR(sa);
3849
3850         if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3851                 kfree(sa);
3852                 return -EPERM;
3853         }
3854
3855         ret = btrfs_get_dev_stats(fs_info, sa);
3856
3857         if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3858                 ret = -EFAULT;
3859
3860         kfree(sa);
3861         return ret;
3862 }
3863
3864 static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
3865                                     void __user *arg)
3866 {
3867         struct btrfs_ioctl_dev_replace_args *p;
3868         int ret;
3869
3870         if (!capable(CAP_SYS_ADMIN))
3871                 return -EPERM;
3872
3873         p = memdup_user(arg, sizeof(*p));
3874         if (IS_ERR(p))
3875                 return PTR_ERR(p);
3876
3877         switch (p->cmd) {
3878         case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3879                 if (sb_rdonly(fs_info->sb)) {
3880                         ret = -EROFS;
3881                         goto out;
3882                 }
3883                 if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {
3884                         ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3885                 } else {
3886                         ret = btrfs_dev_replace_by_ioctl(fs_info, p);
3887                         btrfs_exclop_finish(fs_info);
3888                 }
3889                 break;
3890         case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3891                 btrfs_dev_replace_status(fs_info, p);
3892                 ret = 0;
3893                 break;
3894         case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3895                 p->result = btrfs_dev_replace_cancel(fs_info);
3896                 ret = 0;
3897                 break;
3898         default:
3899                 ret = -EINVAL;
3900                 break;
3901         }
3902
3903         if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
3904                 ret = -EFAULT;
3905 out:
3906         kfree(p);
3907         return ret;
3908 }
3909
3910 static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3911 {
3912         int ret = 0;
3913         int i;
3914         u64 rel_ptr;
3915         int size;
3916         struct btrfs_ioctl_ino_path_args *ipa = NULL;
3917         struct inode_fs_paths *ipath = NULL;
3918         struct btrfs_path *path;
3919
3920         if (!capable(CAP_DAC_READ_SEARCH))
3921                 return -EPERM;
3922
3923         path = btrfs_alloc_path();
3924         if (!path) {
3925                 ret = -ENOMEM;
3926                 goto out;
3927         }
3928
3929         ipa = memdup_user(arg, sizeof(*ipa));
3930         if (IS_ERR(ipa)) {
3931                 ret = PTR_ERR(ipa);
3932                 ipa = NULL;
3933                 goto out;
3934         }
3935
3936         size = min_t(u32, ipa->size, 4096);
3937         ipath = init_ipath(size, root, path);
3938         if (IS_ERR(ipath)) {
3939                 ret = PTR_ERR(ipath);
3940                 ipath = NULL;
3941                 goto out;
3942         }
3943
3944         ret = paths_from_inode(ipa->inum, ipath);
3945         if (ret < 0)
3946                 goto out;
3947
3948         for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3949                 rel_ptr = ipath->fspath->val[i] -
3950                           (u64)(unsigned long)ipath->fspath->val;
3951                 ipath->fspath->val[i] = rel_ptr;
3952         }
3953
3954         ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
3955                            ipath->fspath, size);
3956         if (ret) {
3957                 ret = -EFAULT;
3958                 goto out;
3959         }
3960
3961 out:
3962         btrfs_free_path(path);
3963         free_ipath(ipath);
3964         kfree(ipa);
3965
3966         return ret;
3967 }
3968
3969 static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3970 {
3971         struct btrfs_data_container *inodes = ctx;
3972         const size_t c = 3 * sizeof(u64);
3973
3974         if (inodes->bytes_left >= c) {
3975                 inodes->bytes_left -= c;
3976                 inodes->val[inodes->elem_cnt] = inum;
3977                 inodes->val[inodes->elem_cnt + 1] = offset;
3978                 inodes->val[inodes->elem_cnt + 2] = root;
3979                 inodes->elem_cnt += 3;
3980         } else {
3981                 inodes->bytes_missing += c - inodes->bytes_left;
3982                 inodes->bytes_left = 0;
3983                 inodes->elem_missed += 3;
3984         }
3985
3986         return 0;
3987 }
3988
3989 static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
3990                                         void __user *arg, int version)
3991 {
3992         int ret = 0;
3993         int size;
3994         struct btrfs_ioctl_logical_ino_args *loi;
3995         struct btrfs_data_container *inodes = NULL;
3996         struct btrfs_path *path = NULL;
3997         bool ignore_offset;
3998
3999         if (!capable(CAP_SYS_ADMIN))
4000                 return -EPERM;
4001
4002         loi = memdup_user(arg, sizeof(*loi));
4003         if (IS_ERR(loi))
4004                 return PTR_ERR(loi);
4005
4006         if (version == 1) {
4007                 ignore_offset = false;
4008                 size = min_t(u32, loi->size, SZ_64K);
4009         } else {
4010                 /* All reserved bits must be 0 for now */
4011                 if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
4012                         ret = -EINVAL;
4013                         goto out_loi;
4014                 }
4015                 /* Only accept flags we have defined so far */
4016                 if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
4017                         ret = -EINVAL;
4018                         goto out_loi;
4019                 }
4020                 ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
4021                 size = min_t(u32, loi->size, SZ_16M);
4022         }
4023
4024         path = btrfs_alloc_path();
4025         if (!path) {
4026                 ret = -ENOMEM;
4027                 goto out;
4028         }
4029
4030         inodes = init_data_container(size);
4031         if (IS_ERR(inodes)) {
4032                 ret = PTR_ERR(inodes);
4033                 inodes = NULL;
4034                 goto out;
4035         }
4036
4037         ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
4038                                           build_ino_list, inodes, ignore_offset);
4039         if (ret == -EINVAL)
4040                 ret = -ENOENT;
4041         if (ret < 0)
4042                 goto out;
4043
4044         ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
4045                            size);
4046         if (ret)
4047                 ret = -EFAULT;
4048
4049 out:
4050         btrfs_free_path(path);
4051         kvfree(inodes);
4052 out_loi:
4053         kfree(loi);
4054
4055         return ret;
4056 }
4057
4058 void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
4059                                struct btrfs_ioctl_balance_args *bargs)
4060 {
4061         struct btrfs_balance_control *bctl = fs_info->balance_ctl;
4062
4063         bargs->flags = bctl->flags;
4064
4065         if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
4066                 bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
4067         if (atomic_read(&fs_info->balance_pause_req))
4068                 bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
4069         if (atomic_read(&fs_info->balance_cancel_req))
4070                 bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
4071
4072         memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
4073         memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
4074         memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
4075
4076         spin_lock(&fs_info->balance_lock);
4077         memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
4078         spin_unlock(&fs_info->balance_lock);
4079 }
4080
4081 static long btrfs_ioctl_balance(struct file *file, void __user *arg)
4082 {
4083         struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4084         struct btrfs_fs_info *fs_info = root->fs_info;
4085         struct btrfs_ioctl_balance_args *bargs;
4086         struct btrfs_balance_control *bctl;
4087         bool need_unlock; /* for mut. excl. ops lock */
4088         int ret;
4089
4090         if (!arg)
4091                 btrfs_warn(fs_info,
4092         "IOC_BALANCE ioctl (v1) is deprecated and will be removed in kernel 5.18");
4093
4094         if (!capable(CAP_SYS_ADMIN))
4095                 return -EPERM;
4096
4097         ret = mnt_want_write_file(file);
4098         if (ret)
4099                 return ret;
4100
4101 again:
4102         if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
4103                 mutex_lock(&fs_info->balance_mutex);
4104                 need_unlock = true;
4105                 goto locked;
4106         }
4107
4108         /*
4109          * mut. excl. ops lock is locked.  Three possibilities:
4110          *   (1) some other op is running
4111          *   (2) balance is running
4112          *   (3) balance is paused -- special case (think resume)
4113          */
4114         mutex_lock(&fs_info->balance_mutex);
4115         if (fs_info->balance_ctl) {
4116                 /* this is either (2) or (3) */
4117                 if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4118                         mutex_unlock(&fs_info->balance_mutex);
4119                         /*
4120                          * Lock released to allow other waiters to continue,
4121                          * we'll reexamine the status again.
4122                          */
4123                         mutex_lock(&fs_info->balance_mutex);
4124
4125                         if (fs_info->balance_ctl &&
4126                             !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
4127                                 /* this is (3) */
4128                                 need_unlock = false;
4129                                 goto locked;
4130                         }
4131
4132                         mutex_unlock(&fs_info->balance_mutex);
4133                         goto again;
4134                 } else {
4135                         /* this is (2) */
4136                         mutex_unlock(&fs_info->balance_mutex);
4137                         ret = -EINPROGRESS;
4138                         goto out;
4139                 }
4140         } else {
4141                 /* this is (1) */
4142                 mutex_unlock(&fs_info->balance_mutex);
4143                 ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
4144                 goto out;
4145         }
4146
4147 locked:
4148
4149         if (arg) {
4150                 bargs = memdup_user(arg, sizeof(*bargs));
4151                 if (IS_ERR(bargs)) {
4152                         ret = PTR_ERR(bargs);
4153                         goto out_unlock;
4154                 }
4155
4156                 if (bargs->flags & BTRFS_BALANCE_RESUME) {
4157                         if (!fs_info->balance_ctl) {
4158                                 ret = -ENOTCONN;
4159                                 goto out_bargs;
4160                         }
4161
4162                         bctl = fs_info->balance_ctl;
4163                         spin_lock(&fs_info->balance_lock);
4164                         bctl->flags |= BTRFS_BALANCE_RESUME;
4165                         spin_unlock(&fs_info->balance_lock);
4166                         btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE);
4167
4168                         goto do_balance;
4169                 }
4170         } else {
4171                 bargs = NULL;
4172         }
4173
4174         if (fs_info->balance_ctl) {
4175                 ret = -EINPROGRESS;
4176                 goto out_bargs;
4177         }
4178
4179         bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4180         if (!bctl) {
4181                 ret = -ENOMEM;
4182                 goto out_bargs;
4183         }
4184
4185         if (arg) {
4186                 memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4187                 memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4188                 memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4189
4190                 bctl->flags = bargs->flags;
4191         } else {
4192                 /* balance everything - no filters */
4193                 bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4194         }
4195
4196         if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4197                 ret = -EINVAL;
4198                 goto out_bctl;
4199         }
4200
4201 do_balance:
4202         /*
4203          * Ownership of bctl and exclusive operation goes to btrfs_balance.
4204          * bctl is freed in reset_balance_state, or, if restriper was paused
4205          * all the way until unmount, in free_fs_info.  The flag should be
4206          * cleared after reset_balance_state.
4207          */
4208         need_unlock = false;
4209
4210         ret = btrfs_balance(fs_info, bctl, bargs);
4211         bctl = NULL;
4212
4213         if ((ret == 0 || ret == -ECANCELED) && arg) {
4214                 if (copy_to_user(arg, bargs, sizeof(*bargs)))
4215                         ret = -EFAULT;
4216         }
4217
4218 out_bctl:
4219         kfree(bctl);
4220 out_bargs:
4221         kfree(bargs);
4222 out_unlock:
4223         mutex_unlock(&fs_info->balance_mutex);
4224         if (need_unlock)
4225                 btrfs_exclop_finish(fs_info);
4226 out:
4227         mnt_drop_write_file(file);
4228         return ret;
4229 }
4230
4231 static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4232 {
4233         if (!capable(CAP_SYS_ADMIN))
4234                 return -EPERM;
4235
4236         switch (cmd) {
4237         case BTRFS_BALANCE_CTL_PAUSE:
4238                 return btrfs_pause_balance(fs_info);
4239         case BTRFS_BALANCE_CTL_CANCEL:
4240                 return btrfs_cancel_balance(fs_info);
4241         }
4242
4243         return -EINVAL;
4244 }
4245
4246 static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4247                                          void __user *arg)
4248 {
4249         struct btrfs_ioctl_balance_args *bargs;
4250         int ret = 0;
4251
4252         if (!capable(CAP_SYS_ADMIN))
4253                 return -EPERM;
4254
4255         mutex_lock(&fs_info->balance_mutex);
4256         if (!fs_info->balance_ctl) {
4257                 ret = -ENOTCONN;
4258                 goto out;
4259         }
4260
4261         bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4262         if (!bargs) {
4263                 ret = -ENOMEM;
4264                 goto out;
4265         }
4266
4267         btrfs_update_ioctl_balance_args(fs_info, bargs);
4268
4269         if (copy_to_user(arg, bargs, sizeof(*bargs)))
4270                 ret = -EFAULT;
4271
4272         kfree(bargs);
4273 out:
4274         mutex_unlock(&fs_info->balance_mutex);
4275         return ret;
4276 }
4277
4278 static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4279 {
4280         struct inode *inode = file_inode(file);
4281         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4282         struct btrfs_ioctl_quota_ctl_args *sa;
4283         int ret;
4284
4285         if (!capable(CAP_SYS_ADMIN))
4286                 return -EPERM;
4287
4288         ret = mnt_want_write_file(file);
4289         if (ret)
4290                 return ret;
4291
4292         sa = memdup_user(arg, sizeof(*sa));
4293         if (IS_ERR(sa)) {
4294                 ret = PTR_ERR(sa);
4295                 goto drop_write;
4296         }
4297
4298         down_write(&fs_info->subvol_sem);
4299
4300         switch (sa->cmd) {
4301         case BTRFS_QUOTA_CTL_ENABLE:
4302                 ret = btrfs_quota_enable(fs_info);
4303                 break;
4304         case BTRFS_QUOTA_CTL_DISABLE:
4305                 ret = btrfs_quota_disable(fs_info);
4306                 break;
4307         default:
4308                 ret = -EINVAL;
4309                 break;
4310         }
4311
4312         kfree(sa);
4313         up_write(&fs_info->subvol_sem);
4314 drop_write:
4315         mnt_drop_write_file(file);
4316         return ret;
4317 }
4318
4319 static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4320 {
4321         struct inode *inode = file_inode(file);
4322         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4323         struct btrfs_root *root = BTRFS_I(inode)->root;
4324         struct btrfs_ioctl_qgroup_assign_args *sa;
4325         struct btrfs_trans_handle *trans;
4326         int ret;
4327         int err;
4328
4329         if (!capable(CAP_SYS_ADMIN))
4330                 return -EPERM;
4331
4332         ret = mnt_want_write_file(file);
4333         if (ret)
4334                 return ret;
4335
4336         sa = memdup_user(arg, sizeof(*sa));
4337         if (IS_ERR(sa)) {
4338                 ret = PTR_ERR(sa);
4339                 goto drop_write;
4340         }
4341
4342         trans = btrfs_join_transaction(root);
4343         if (IS_ERR(trans)) {
4344                 ret = PTR_ERR(trans);
4345                 goto out;
4346         }
4347
4348         if (sa->assign) {
4349                 ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
4350         } else {
4351                 ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
4352         }
4353
4354         /* update qgroup status and info */
4355         err = btrfs_run_qgroups(trans);
4356         if (err < 0)
4357                 btrfs_handle_fs_error(fs_info, err,
4358                                       "failed to update qgroup status and info");
4359         err = btrfs_end_transaction(trans);
4360         if (err && !ret)
4361                 ret = err;
4362
4363 out:
4364         kfree(sa);
4365 drop_write:
4366         mnt_drop_write_file(file);
4367         return ret;
4368 }
4369
4370 static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4371 {
4372         struct inode *inode = file_inode(file);
4373         struct btrfs_root *root = BTRFS_I(inode)->root;
4374         struct btrfs_ioctl_qgroup_create_args *sa;
4375         struct btrfs_trans_handle *trans;
4376         int ret;
4377         int err;
4378
4379         if (!capable(CAP_SYS_ADMIN))
4380                 return -EPERM;
4381
4382         ret = mnt_want_write_file(file);
4383         if (ret)
4384                 return ret;
4385
4386         sa = memdup_user(arg, sizeof(*sa));
4387         if (IS_ERR(sa)) {
4388                 ret = PTR_ERR(sa);
4389                 goto drop_write;
4390         }
4391
4392         if (!sa->qgroupid) {
4393                 ret = -EINVAL;
4394                 goto out;
4395         }
4396
4397         trans = btrfs_join_transaction(root);
4398         if (IS_ERR(trans)) {
4399                 ret = PTR_ERR(trans);
4400                 goto out;
4401         }
4402
4403         if (sa->create) {
4404                 ret = btrfs_create_qgroup(trans, sa->qgroupid);
4405         } else {
4406                 ret = btrfs_remove_qgroup(trans, sa->qgroupid);
4407         }
4408
4409         err = btrfs_end_transaction(trans);
4410         if (err && !ret)
4411                 ret = err;
4412
4413 out:
4414         kfree(sa);
4415 drop_write:
4416         mnt_drop_write_file(file);
4417         return ret;
4418 }
4419
4420 static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4421 {
4422         struct inode *inode = file_inode(file);
4423         struct btrfs_root *root = BTRFS_I(inode)->root;
4424         struct btrfs_ioctl_qgroup_limit_args *sa;
4425         struct btrfs_trans_handle *trans;
4426         int ret;
4427         int err;
4428         u64 qgroupid;
4429
4430         if (!capable(CAP_SYS_ADMIN))
4431                 return -EPERM;
4432
4433         ret = mnt_want_write_file(file);
4434         if (ret)
4435                 return ret;
4436
4437         sa = memdup_user(arg, sizeof(*sa));
4438         if (IS_ERR(sa)) {
4439                 ret = PTR_ERR(sa);
4440                 goto drop_write;
4441         }
4442
4443         trans = btrfs_join_transaction(root);
4444         if (IS_ERR(trans)) {
4445                 ret = PTR_ERR(trans);
4446                 goto out;
4447         }
4448
4449         qgroupid = sa->qgroupid;
4450         if (!qgroupid) {
4451                 /* take the current subvol as qgroup */
4452                 qgroupid = root->root_key.objectid;
4453         }
4454
4455         ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
4456
4457         err = btrfs_end_transaction(trans);
4458         if (err && !ret)
4459                 ret = err;
4460
4461 out:
4462         kfree(sa);
4463 drop_write:
4464         mnt_drop_write_file(file);
4465         return ret;
4466 }
4467
4468 static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4469 {
4470         struct inode *inode = file_inode(file);
4471         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4472         struct btrfs_ioctl_quota_rescan_args *qsa;
4473         int ret;
4474
4475         if (!capable(CAP_SYS_ADMIN))
4476                 return -EPERM;
4477
4478         ret = mnt_want_write_file(file);
4479         if (ret)
4480                 return ret;
4481
4482         qsa = memdup_user(arg, sizeof(*qsa));
4483         if (IS_ERR(qsa)) {
4484                 ret = PTR_ERR(qsa);
4485                 goto drop_write;
4486         }
4487
4488         if (qsa->flags) {
4489                 ret = -EINVAL;
4490                 goto out;
4491         }
4492
4493         ret = btrfs_qgroup_rescan(fs_info);
4494
4495 out:
4496         kfree(qsa);
4497 drop_write:
4498         mnt_drop_write_file(file);
4499         return ret;
4500 }
4501
4502 static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
4503                                                 void __user *arg)
4504 {
4505         struct btrfs_ioctl_quota_rescan_args qsa = {0};
4506
4507         if (!capable(CAP_SYS_ADMIN))
4508                 return -EPERM;
4509
4510         if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4511                 qsa.flags = 1;
4512                 qsa.progress = fs_info->qgroup_rescan_progress.objectid;
4513         }
4514
4515         if (copy_to_user(arg, &qsa, sizeof(qsa)))
4516                 return -EFAULT;
4517
4518         return 0;
4519 }
4520
4521 static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
4522                                                 void __user *arg)
4523 {
4524         if (!capable(CAP_SYS_ADMIN))
4525                 return -EPERM;
4526
4527         return btrfs_qgroup_wait_for_completion(fs_info, true);
4528 }
4529
4530 static long _btrfs_ioctl_set_received_subvol(struct file *file,
4531                                             struct user_namespace *mnt_userns,
4532                                             struct btrfs_ioctl_received_subvol_args *sa)
4533 {
4534         struct inode *inode = file_inode(file);
4535         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4536         struct btrfs_root *root = BTRFS_I(inode)->root;
4537         struct btrfs_root_item *root_item = &root->root_item;
4538         struct btrfs_trans_handle *trans;
4539         struct timespec64 ct = current_time(inode);
4540         int ret = 0;
4541         int received_uuid_changed;
4542
4543         if (!inode_owner_or_capable(mnt_userns, inode))
4544                 return -EPERM;
4545
4546         ret = mnt_want_write_file(file);
4547         if (ret < 0)
4548                 return ret;
4549
4550         down_write(&fs_info->subvol_sem);
4551
4552         if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
4553                 ret = -EINVAL;
4554                 goto out;
4555         }
4556
4557         if (btrfs_root_readonly(root)) {
4558                 ret = -EROFS;
4559                 goto out;
4560         }
4561
4562         /*
4563          * 1 - root item
4564          * 2 - uuid items (received uuid + subvol uuid)
4565          */
4566         trans = btrfs_start_transaction(root, 3);
4567         if (IS_ERR(trans)) {
4568                 ret = PTR_ERR(trans);
4569                 trans = NULL;
4570                 goto out;
4571         }
4572
4573         sa->rtransid = trans->transid;
4574         sa->rtime.sec = ct.tv_sec;
4575         sa->rtime.nsec = ct.tv_nsec;
4576
4577         received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4578                                        BTRFS_UUID_SIZE);
4579         if (received_uuid_changed &&
4580             !btrfs_is_empty_uuid(root_item->received_uuid)) {
4581                 ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
4582                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4583                                           root->root_key.objectid);
4584                 if (ret && ret != -ENOENT) {
4585                         btrfs_abort_transaction(trans, ret);
4586                         btrfs_end_transaction(trans);
4587                         goto out;
4588                 }
4589         }
4590         memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4591         btrfs_set_root_stransid(root_item, sa->stransid);
4592         btrfs_set_root_rtransid(root_item, sa->rtransid);
4593         btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4594         btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4595         btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4596         btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4597
4598         ret = btrfs_update_root(trans, fs_info->tree_root,
4599                                 &root->root_key, &root->root_item);
4600         if (ret < 0) {
4601                 btrfs_end_transaction(trans);
4602                 goto out;
4603         }
4604         if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4605                 ret = btrfs_uuid_tree_add(trans, sa->uuid,
4606                                           BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4607                                           root->root_key.objectid);
4608                 if (ret < 0 && ret != -EEXIST) {
4609                         btrfs_abort_transaction(trans, ret);
4610                         btrfs_end_transaction(trans);
4611                         goto out;
4612                 }
4613         }
4614         ret = btrfs_commit_transaction(trans);
4615 out:
4616         up_write(&fs_info->subvol_sem);
4617         mnt_drop_write_file(file);
4618         return ret;
4619 }
4620
4621 #ifdef CONFIG_64BIT
4622 static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4623                                                 void __user *arg)
4624 {
4625         struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4626         struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4627         int ret = 0;
4628
4629         args32 = memdup_user(arg, sizeof(*args32));
4630         if (IS_ERR(args32))
4631                 return PTR_ERR(args32);
4632
4633         args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
4634         if (!args64) {
4635                 ret = -ENOMEM;
4636                 goto out;
4637         }
4638
4639         memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4640         args64->stransid = args32->stransid;
4641         args64->rtransid = args32->rtransid;
4642         args64->stime.sec = args32->stime.sec;
4643         args64->stime.nsec = args32->stime.nsec;
4644         args64->rtime.sec = args32->rtime.sec;
4645         args64->rtime.nsec = args32->rtime.nsec;
4646         args64->flags = args32->flags;
4647
4648         ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_user_ns(file), args64);
4649         if (ret)
4650                 goto out;
4651
4652         memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4653         args32->stransid = args64->stransid;
4654         args32->rtransid = args64->rtransid;
4655         args32->stime.sec = args64->stime.sec;
4656         args32->stime.nsec = args64->stime.nsec;
4657         args32->rtime.sec = args64->rtime.sec;
4658         args32->rtime.nsec = args64->rtime.nsec;
4659         args32->flags = args64->flags;
4660
4661         ret = copy_to_user(arg, args32, sizeof(*args32));
4662         if (ret)
4663                 ret = -EFAULT;
4664
4665 out:
4666         kfree(args32);
4667         kfree(args64);
4668         return ret;
4669 }
4670 #endif
4671
4672 static long btrfs_ioctl_set_received_subvol(struct file *file,
4673                                             void __user *arg)
4674 {
4675         struct btrfs_ioctl_received_subvol_args *sa = NULL;
4676         int ret = 0;
4677
4678         sa = memdup_user(arg, sizeof(*sa));
4679         if (IS_ERR(sa))
4680                 return PTR_ERR(sa);
4681
4682         ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_user_ns(file), sa);
4683
4684         if (ret)
4685                 goto out;
4686
4687         ret = copy_to_user(arg, sa, sizeof(*sa));
4688         if (ret)
4689                 ret = -EFAULT;
4690
4691 out:
4692         kfree(sa);
4693         return ret;
4694 }
4695
4696 static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
4697                                         void __user *arg)
4698 {
4699         size_t len;
4700         int ret;
4701         char label[BTRFS_LABEL_SIZE];
4702
4703         spin_lock(&fs_info->super_lock);
4704         memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4705         spin_unlock(&fs_info->super_lock);
4706
4707         len = strnlen(label, BTRFS_LABEL_SIZE);
4708
4709         if (len == BTRFS_LABEL_SIZE) {
4710                 btrfs_warn(fs_info,
4711                            "label is too long, return the first %zu bytes",
4712                            --len);
4713         }
4714
4715         ret = copy_to_user(arg, label, len);
4716
4717         return ret ? -EFAULT : 0;
4718 }
4719
4720 static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4721 {
4722         struct inode *inode = file_inode(file);
4723         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4724         struct btrfs_root *root = BTRFS_I(inode)->root;
4725         struct btrfs_super_block *super_block = fs_info->super_copy;
4726         struct btrfs_trans_handle *trans;
4727         char label[BTRFS_LABEL_SIZE];
4728         int ret;
4729
4730         if (!capable(CAP_SYS_ADMIN))
4731                 return -EPERM;
4732
4733         if (copy_from_user(label, arg, sizeof(label)))
4734                 return -EFAULT;
4735
4736         if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4737                 btrfs_err(fs_info,
4738                           "unable to set label with more than %d bytes",
4739                           BTRFS_LABEL_SIZE - 1);
4740                 return -EINVAL;
4741         }
4742
4743         ret = mnt_want_write_file(file);
4744         if (ret)
4745                 return ret;
4746
4747         trans = btrfs_start_transaction(root, 0);
4748         if (IS_ERR(trans)) {
4749                 ret = PTR_ERR(trans);
4750                 goto out_unlock;
4751         }
4752
4753         spin_lock(&fs_info->super_lock);
4754         strcpy(super_block->label, label);
4755         spin_unlock(&fs_info->super_lock);
4756         ret = btrfs_commit_transaction(trans);
4757
4758 out_unlock:
4759         mnt_drop_write_file(file);
4760         return ret;
4761 }
4762
4763 #define INIT_FEATURE_FLAGS(suffix) \
4764         { .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4765           .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4766           .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4767
4768 int btrfs_ioctl_get_supported_features(void __user *arg)
4769 {
4770         static const struct btrfs_ioctl_feature_flags features[3] = {
4771                 INIT_FEATURE_FLAGS(SUPP),
4772                 INIT_FEATURE_FLAGS(SAFE_SET),
4773                 INIT_FEATURE_FLAGS(SAFE_CLEAR)
4774         };
4775
4776         if (copy_to_user(arg, &features, sizeof(features)))
4777                 return -EFAULT;
4778
4779         return 0;
4780 }
4781
4782 static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
4783                                         void __user *arg)
4784 {
4785         struct btrfs_super_block *super_block = fs_info->super_copy;
4786         struct btrfs_ioctl_feature_flags features;
4787
4788         features.compat_flags = btrfs_super_compat_flags(super_block);
4789         features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4790         features.incompat_flags = btrfs_super_incompat_flags(super_block);
4791
4792         if (copy_to_user(arg, &features, sizeof(features)))
4793                 return -EFAULT;
4794
4795         return 0;
4796 }
4797
4798 static int check_feature_bits(struct btrfs_fs_info *fs_info,
4799                               enum btrfs_feature_set set,
4800                               u64 change_mask, u64 flags, u64 supported_flags,
4801                               u64 safe_set, u64 safe_clear)
4802 {
4803         const char *type = btrfs_feature_set_name(set);
4804         char *names;
4805         u64 disallowed, unsupported;
4806         u64 set_mask = flags & change_mask;
4807         u64 clear_mask = ~flags & change_mask;
4808
4809         unsupported = set_mask & ~supported_flags;
4810         if (unsupported) {
4811                 names = btrfs_printable_features(set, unsupported);
4812                 if (names) {
4813                         btrfs_warn(fs_info,
4814                                    "this kernel does not support the %s feature bit%s",
4815                                    names, strchr(names, ',') ? "s" : "");
4816                         kfree(names);
4817                 } else
4818                         btrfs_warn(fs_info,
4819                                    "this kernel does not support %s bits 0x%llx",
4820                                    type, unsupported);
4821                 return -EOPNOTSUPP;
4822         }
4823
4824         disallowed = set_mask & ~safe_set;
4825         if (disallowed) {
4826                 names = btrfs_printable_features(set, disallowed);
4827                 if (names) {
4828                         btrfs_warn(fs_info,
4829                                    "can't set the %s feature bit%s while mounted",
4830                                    names, strchr(names, ',') ? "s" : "");
4831                         kfree(names);
4832                 } else
4833                         btrfs_warn(fs_info,
4834                                    "can't set %s bits 0x%llx while mounted",
4835                                    type, disallowed);
4836                 return -EPERM;
4837         }
4838
4839         disallowed = clear_mask & ~safe_clear;
4840         if (disallowed) {
4841                 names = btrfs_printable_features(set, disallowed);
4842                 if (names) {
4843                         btrfs_warn(fs_info,
4844                                    "can't clear the %s feature bit%s while mounted",
4845                                    names, strchr(names, ',') ? "s" : "");
4846                         kfree(names);
4847                 } else
4848                         btrfs_warn(fs_info,
4849                                    "can't clear %s bits 0x%llx while mounted",
4850                                    type, disallowed);
4851                 return -EPERM;
4852         }
4853
4854         return 0;
4855 }
4856
4857 #define check_feature(fs_info, change_mask, flags, mask_base)   \
4858 check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags,       \
4859                    BTRFS_FEATURE_ ## mask_base ## _SUPP,        \
4860                    BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,    \
4861                    BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4862
4863 static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4864 {
4865         struct inode *inode = file_inode(file);
4866         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4867         struct btrfs_root *root = BTRFS_I(inode)->root;
4868         struct btrfs_super_block *super_block = fs_info->super_copy;
4869         struct btrfs_ioctl_feature_flags flags[2];
4870         struct btrfs_trans_handle *trans;
4871         u64 newflags;
4872         int ret;
4873
4874         if (!capable(CAP_SYS_ADMIN))
4875                 return -EPERM;
4876
4877         if (copy_from_user(flags, arg, sizeof(flags)))
4878                 return -EFAULT;
4879
4880         /* Nothing to do */
4881         if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4882             !flags[0].incompat_flags)
4883                 return 0;
4884
4885         ret = check_feature(fs_info, flags[0].compat_flags,
4886                             flags[1].compat_flags, COMPAT);
4887         if (ret)
4888                 return ret;
4889
4890         ret = check_feature(fs_info, flags[0].compat_ro_flags,
4891                             flags[1].compat_ro_flags, COMPAT_RO);
4892         if (ret)
4893                 return ret;
4894
4895         ret = check_feature(fs_info, flags[0].incompat_flags,
4896                             flags[1].incompat_flags, INCOMPAT);
4897         if (ret)
4898                 return ret;
4899
4900         ret = mnt_want_write_file(file);
4901         if (ret)
4902                 return ret;
4903
4904         trans = btrfs_start_transaction(root, 0);
4905         if (IS_ERR(trans)) {
4906                 ret = PTR_ERR(trans);
4907                 goto out_drop_write;
4908         }
4909
4910         spin_lock(&fs_info->super_lock);
4911         newflags = btrfs_super_compat_flags(super_block);
4912         newflags |= flags[0].compat_flags & flags[1].compat_flags;
4913         newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4914         btrfs_set_super_compat_flags(super_block, newflags);
4915
4916         newflags = btrfs_super_compat_ro_flags(super_block);
4917         newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4918         newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4919         btrfs_set_super_compat_ro_flags(super_block, newflags);
4920
4921         newflags = btrfs_super_incompat_flags(super_block);
4922         newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4923         newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4924         btrfs_set_super_incompat_flags(super_block, newflags);
4925         spin_unlock(&fs_info->super_lock);
4926
4927         ret = btrfs_commit_transaction(trans);
4928 out_drop_write:
4929         mnt_drop_write_file(file);
4930
4931         return ret;
4932 }
4933
4934 static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
4935 {
4936         struct btrfs_ioctl_send_args *arg;
4937         int ret;
4938
4939         if (compat) {
4940 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4941                 struct btrfs_ioctl_send_args_32 args32;
4942
4943                 ret = copy_from_user(&args32, argp, sizeof(args32));
4944                 if (ret)
4945                         return -EFAULT;
4946                 arg = kzalloc(sizeof(*arg), GFP_KERNEL);
4947                 if (!arg)
4948                         return -ENOMEM;
4949                 arg->send_fd = args32.send_fd;
4950                 arg->clone_sources_count = args32.clone_sources_count;
4951                 arg->clone_sources = compat_ptr(args32.clone_sources);
4952                 arg->parent_root = args32.parent_root;
4953                 arg->flags = args32.flags;
4954                 memcpy(arg->reserved, args32.reserved,
4955                        sizeof(args32.reserved));
4956 #else
4957                 return -ENOTTY;
4958 #endif
4959         } else {
4960                 arg = memdup_user(argp, sizeof(*arg));
4961                 if (IS_ERR(arg))
4962                         return PTR_ERR(arg);
4963         }
4964         ret = btrfs_ioctl_send(file, arg);
4965         kfree(arg);
4966         return ret;
4967 }
4968
4969 long btrfs_ioctl(struct file *file, unsigned int
4970                 cmd, unsigned long arg)
4971 {
4972         struct inode *inode = file_inode(file);
4973         struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4974         struct btrfs_root *root = BTRFS_I(inode)->root;
4975         void __user *argp = (void __user *)arg;
4976
4977         switch (cmd) {
4978         case FS_IOC_GETVERSION:
4979                 return btrfs_ioctl_getversion(file, argp);
4980         case FS_IOC_GETFSLABEL:
4981                 return btrfs_ioctl_get_fslabel(fs_info, argp);
4982         case FS_IOC_SETFSLABEL:
4983                 return btrfs_ioctl_set_fslabel(file, argp);
4984         case FITRIM:
4985                 return btrfs_ioctl_fitrim(fs_info, argp);
4986         case BTRFS_IOC_SNAP_CREATE:
4987                 return btrfs_ioctl_snap_create(file, argp, 0);
4988         case BTRFS_IOC_SNAP_CREATE_V2:
4989                 return btrfs_ioctl_snap_create_v2(file, argp, 0);
4990         case BTRFS_IOC_SUBVOL_CREATE:
4991                 return btrfs_ioctl_snap_create(file, argp, 1);
4992         case BTRFS_IOC_SUBVOL_CREATE_V2:
4993                 return btrfs_ioctl_snap_create_v2(file, argp, 1);
4994         case BTRFS_IOC_SNAP_DESTROY:
4995                 return btrfs_ioctl_snap_destroy(file, argp, false);
4996         case BTRFS_IOC_SNAP_DESTROY_V2:
4997                 return btrfs_ioctl_snap_destroy(file, argp, true);
4998         case BTRFS_IOC_SUBVOL_GETFLAGS:
4999                 return btrfs_ioctl_subvol_getflags(file, argp);
5000         case BTRFS_IOC_SUBVOL_SETFLAGS:
5001                 return btrfs_ioctl_subvol_setflags(file, argp);
5002         case BTRFS_IOC_DEFAULT_SUBVOL:
5003                 return btrfs_ioctl_default_subvol(file, argp);
5004         case BTRFS_IOC_DEFRAG:
5005                 return btrfs_ioctl_defrag(file, NULL);
5006         case BTRFS_IOC_DEFRAG_RANGE:
5007                 return btrfs_ioctl_defrag(file, argp);
5008         case BTRFS_IOC_RESIZE:
5009                 return btrfs_ioctl_resize(file, argp);
5010         case BTRFS_IOC_ADD_DEV:
5011                 return btrfs_ioctl_add_dev(fs_info, argp);
5012         case BTRFS_IOC_RM_DEV:
5013                 return btrfs_ioctl_rm_dev(file, argp);
5014         case BTRFS_IOC_RM_DEV_V2:
5015                 return btrfs_ioctl_rm_dev_v2(file, argp);
5016         case BTRFS_IOC_FS_INFO:
5017                 return btrfs_ioctl_fs_info(fs_info, argp);
5018         case BTRFS_IOC_DEV_INFO:
5019                 return btrfs_ioctl_dev_info(fs_info, argp);
5020         case BTRFS_IOC_BALANCE:
5021                 return btrfs_ioctl_balance(file, NULL);
5022         case BTRFS_IOC_TREE_SEARCH:
5023                 return btrfs_ioctl_tree_search(file, argp);
5024         case BTRFS_IOC_TREE_SEARCH_V2:
5025                 return btrfs_ioctl_tree_search_v2(file, argp);
5026         case BTRFS_IOC_INO_LOOKUP:
5027                 return btrfs_ioctl_ino_lookup(file, argp);
5028         case BTRFS_IOC_INO_PATHS:
5029                 return btrfs_ioctl_ino_to_path(root, argp);
5030         case BTRFS_IOC_LOGICAL_INO:
5031                 return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
5032         case BTRFS_IOC_LOGICAL_INO_V2:
5033                 return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
5034         case BTRFS_IOC_SPACE_INFO:
5035                 return btrfs_ioctl_space_info(fs_info, argp);
5036         case BTRFS_IOC_SYNC: {
5037                 int ret;
5038
5039                 ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
5040                 if (ret)
5041                         return ret;
5042                 ret = btrfs_sync_fs(inode->i_sb, 1);
5043                 /*
5044                  * The transaction thread may want to do more work,
5045                  * namely it pokes the cleaner kthread that will start
5046                  * processing uncleaned subvols.
5047                  */
5048                 wake_up_process(fs_info->transaction_kthread);
5049                 return ret;
5050         }
5051         case BTRFS_IOC_START_SYNC:
5052                 return btrfs_ioctl_start_sync(root, argp);
5053         case BTRFS_IOC_WAIT_SYNC:
5054                 return btrfs_ioctl_wait_sync(fs_info, argp);
5055         case BTRFS_IOC_SCRUB:
5056                 return btrfs_ioctl_scrub(file, argp);
5057         case BTRFS_IOC_SCRUB_CANCEL:
5058                 return btrfs_ioctl_scrub_cancel(fs_info);
5059         case BTRFS_IOC_SCRUB_PROGRESS:
5060                 return btrfs_ioctl_scrub_progress(fs_info, argp);
5061         case BTRFS_IOC_BALANCE_V2:
5062                 return btrfs_ioctl_balance(file, argp);
5063         case BTRFS_IOC_BALANCE_CTL:
5064                 return btrfs_ioctl_balance_ctl(fs_info, arg);
5065         case BTRFS_IOC_BALANCE_PROGRESS:
5066                 return btrfs_ioctl_balance_progress(fs_info, argp);
5067         case BTRFS_IOC_SET_RECEIVED_SUBVOL:
5068                 return btrfs_ioctl_set_received_subvol(file, argp);
5069 #ifdef CONFIG_64BIT
5070         case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
5071                 return btrfs_ioctl_set_received_subvol_32(file, argp);
5072 #endif
5073         case BTRFS_IOC_SEND:
5074                 return _btrfs_ioctl_send(file, argp, false);
5075 #if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
5076         case BTRFS_IOC_SEND_32:
5077                 return _btrfs_ioctl_send(file, argp, true);
5078 #endif
5079         case BTRFS_IOC_GET_DEV_STATS:
5080                 return btrfs_ioctl_get_dev_stats(fs_info, argp);
5081         case BTRFS_IOC_QUOTA_CTL:
5082                 return btrfs_ioctl_quota_ctl(file, argp);
5083         case BTRFS_IOC_QGROUP_ASSIGN:
5084                 return btrfs_ioctl_qgroup_assign(file, argp);
5085         case BTRFS_IOC_QGROUP_CREATE:
5086                 return btrfs_ioctl_qgroup_create(file, argp);
5087         case BTRFS_IOC_QGROUP_LIMIT:
5088                 return btrfs_ioctl_qgroup_limit(file, argp);
5089         case BTRFS_IOC_QUOTA_RESCAN:
5090                 return btrfs_ioctl_quota_rescan(file, argp);
5091         case BTRFS_IOC_QUOTA_RESCAN_STATUS:
5092                 return btrfs_ioctl_quota_rescan_status(fs_info, argp);
5093         case BTRFS_IOC_QUOTA_RESCAN_WAIT:
5094                 return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
5095         case BTRFS_IOC_DEV_REPLACE:
5096                 return btrfs_ioctl_dev_replace(fs_info, argp);
5097         case BTRFS_IOC_GET_SUPPORTED_FEATURES:
5098                 return btrfs_ioctl_get_supported_features(argp);
5099         case BTRFS_IOC_GET_FEATURES:
5100                 return btrfs_ioctl_get_features(fs_info, argp);
5101         case BTRFS_IOC_SET_FEATURES:
5102                 return btrfs_ioctl_set_features(file, argp);
5103         case BTRFS_IOC_GET_SUBVOL_INFO:
5104                 return btrfs_ioctl_get_subvol_info(file, argp);
5105         case BTRFS_IOC_GET_SUBVOL_ROOTREF:
5106                 return btrfs_ioctl_get_subvol_rootref(file, argp);
5107         case BTRFS_IOC_INO_LOOKUP_USER:
5108                 return btrfs_ioctl_ino_lookup_user(file, argp);
5109         case FS_IOC_ENABLE_VERITY:
5110                 return fsverity_ioctl_enable(file, (const void __user *)argp);
5111         case FS_IOC_MEASURE_VERITY:
5112                 return fsverity_ioctl_measure(file, argp);
5113         }
5114
5115         return -ENOTTY;
5116 }
5117
5118 #ifdef CONFIG_COMPAT
5119 long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
5120 {
5121         /*
5122          * These all access 32-bit values anyway so no further
5123          * handling is necessary.
5124          */
5125         switch (cmd) {
5126         case FS_IOC32_GETVERSION:
5127                 cmd = FS_IOC_GETVERSION;
5128                 break;
5129         }
5130
5131         return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
5132 }
5133 #endif