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 "ctree.h"
  30#include "disk-io.h"
  31#include "export.h"
  32#include "transaction.h"
  33#include "btrfs_inode.h"
  34#include "print-tree.h"
  35#include "volumes.h"
  36#include "locking.h"
  37#include "inode-map.h"
  38#include "backref.h"
  39#include "rcu-string.h"
  40#include "send.h"
  41#include "dev-replace.h"
  42#include "props.h"
  43#include "sysfs.h"
  44#include "qgroup.h"
  45#include "tree-log.h"
  46#include "compression.h"
  47#include "space-info.h"
  48#include "delalloc-space.h"
  49#include "block-group.h"
  50
  51#ifdef CONFIG_64BIT
  52/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
  53 * structures are incorrect, as the timespec structure from userspace
  54 * is 4 bytes too small. We define these alternatives here to teach
  55 * the kernel about the 32-bit struct packing.
  56 */
  57struct btrfs_ioctl_timespec_32 {
  58	__u64 sec;
  59	__u32 nsec;
  60} __attribute__ ((__packed__));
  61
  62struct btrfs_ioctl_received_subvol_args_32 {
  63	char	uuid[BTRFS_UUID_SIZE];	/* in */
  64	__u64	stransid;		/* in */
  65	__u64	rtransid;		/* out */
  66	struct btrfs_ioctl_timespec_32 stime; /* in */
  67	struct btrfs_ioctl_timespec_32 rtime; /* out */
  68	__u64	flags;			/* in */
  69	__u64	reserved[16];		/* in */
  70} __attribute__ ((__packed__));
  71
  72#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
  73				struct btrfs_ioctl_received_subvol_args_32)
  74#endif
  75
  76#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
  77struct btrfs_ioctl_send_args_32 {
  78	__s64 send_fd;			/* in */
  79	__u64 clone_sources_count;	/* in */
  80	compat_uptr_t clone_sources;	/* in */
  81	__u64 parent_root;		/* in */
  82	__u64 flags;			/* in */
  83	__u64 reserved[4];		/* in */
  84} __attribute__ ((__packed__));
  85
  86#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
  87			       struct btrfs_ioctl_send_args_32)
  88#endif
  89
  90/* Mask out flags that are inappropriate for the given type of inode. */
  91static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
  92		unsigned int flags)
  93{
  94	if (S_ISDIR(inode->i_mode))
  95		return flags;
  96	else if (S_ISREG(inode->i_mode))
  97		return flags & ~FS_DIRSYNC_FL;
  98	else
  99		return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
 100}
 101
 102/*
 103 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
 104 * ioctl.
 105 */
 106static unsigned int btrfs_inode_flags_to_fsflags(unsigned int flags)
 107{
 108	unsigned int iflags = 0;
 109
 110	if (flags & BTRFS_INODE_SYNC)
 111		iflags |= FS_SYNC_FL;
 112	if (flags & BTRFS_INODE_IMMUTABLE)
 113		iflags |= FS_IMMUTABLE_FL;
 114	if (flags & BTRFS_INODE_APPEND)
 115		iflags |= FS_APPEND_FL;
 116	if (flags & BTRFS_INODE_NODUMP)
 117		iflags |= FS_NODUMP_FL;
 118	if (flags & BTRFS_INODE_NOATIME)
 119		iflags |= FS_NOATIME_FL;
 120	if (flags & BTRFS_INODE_DIRSYNC)
 121		iflags |= FS_DIRSYNC_FL;
 122	if (flags & BTRFS_INODE_NODATACOW)
 123		iflags |= FS_NOCOW_FL;
 124
 125	if (flags & BTRFS_INODE_NOCOMPRESS)
 126		iflags |= FS_NOCOMP_FL;
 127	else if (flags & BTRFS_INODE_COMPRESS)
 128		iflags |= FS_COMPR_FL;
 129
 130	return iflags;
 131}
 132
 133/*
 134 * Update inode->i_flags based on the btrfs internal flags.
 135 */
 136void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
 137{
 138	struct btrfs_inode *binode = BTRFS_I(inode);
 139	unsigned int new_fl = 0;
 140
 141	if (binode->flags & BTRFS_INODE_SYNC)
 142		new_fl |= S_SYNC;
 143	if (binode->flags & BTRFS_INODE_IMMUTABLE)
 144		new_fl |= S_IMMUTABLE;
 145	if (binode->flags & BTRFS_INODE_APPEND)
 146		new_fl |= S_APPEND;
 147	if (binode->flags & BTRFS_INODE_NOATIME)
 148		new_fl |= S_NOATIME;
 149	if (binode->flags & BTRFS_INODE_DIRSYNC)
 150		new_fl |= S_DIRSYNC;
 151
 152	set_mask_bits(&inode->i_flags,
 153		      S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC,
 154		      new_fl);
 155}
 156
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 157static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 158{
 159	struct btrfs_inode *binode = BTRFS_I(file_inode(file));
 160	unsigned int flags = btrfs_inode_flags_to_fsflags(binode->flags);
 161
 162	if (copy_to_user(arg, &flags, sizeof(flags)))
 163		return -EFAULT;
 164	return 0;
 165}
 166
 167/*
 168 * Check if @flags are a supported and valid set of FS_*_FL flags and that
 169 * the old and new flags are not conflicting
 170 */
 171static int check_fsflags(unsigned int old_flags, unsigned int flags)
 172{
 173	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 174		      FS_NOATIME_FL | FS_NODUMP_FL | \
 175		      FS_SYNC_FL | FS_DIRSYNC_FL | \
 176		      FS_NOCOMP_FL | FS_COMPR_FL |
 177		      FS_NOCOW_FL))
 178		return -EOPNOTSUPP;
 179
 180	/* COMPR and NOCOMP on new/old are valid */
 181	if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 182		return -EINVAL;
 183
 184	if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
 185		return -EINVAL;
 186
 187	/* NOCOW and compression options are mutually exclusive */
 188	if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
 189		return -EINVAL;
 190	if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
 191		return -EINVAL;
 192
 193	return 0;
 194}
 195
 196static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 197{
 198	struct inode *inode = file_inode(file);
 199	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 200	struct btrfs_inode *binode = BTRFS_I(inode);
 201	struct btrfs_root *root = binode->root;
 202	struct btrfs_trans_handle *trans;
 203	unsigned int fsflags, old_fsflags;
 204	int ret;
 205	const char *comp = NULL;
 206	u32 binode_flags;
 
 207
 208	if (!inode_owner_or_capable(inode))
 209		return -EPERM;
 210
 211	if (btrfs_root_readonly(root))
 212		return -EROFS;
 213
 214	if (copy_from_user(&fsflags, arg, sizeof(fsflags)))
 215		return -EFAULT;
 216
 
 
 
 
 217	ret = mnt_want_write_file(file);
 218	if (ret)
 219		return ret;
 220
 221	inode_lock(inode);
 222	fsflags = btrfs_mask_fsflags_for_type(inode, fsflags);
 223	old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags);
 224
 225	ret = vfs_ioc_setflags_prepare(inode, old_fsflags, fsflags);
 226	if (ret)
 227		goto out_unlock;
 228
 229	ret = check_fsflags(old_fsflags, fsflags);
 230	if (ret)
 231		goto out_unlock;
 
 
 
 
 
 232
 233	binode_flags = binode->flags;
 234	if (fsflags & FS_SYNC_FL)
 235		binode_flags |= BTRFS_INODE_SYNC;
 236	else
 237		binode_flags &= ~BTRFS_INODE_SYNC;
 238	if (fsflags & FS_IMMUTABLE_FL)
 239		binode_flags |= BTRFS_INODE_IMMUTABLE;
 240	else
 241		binode_flags &= ~BTRFS_INODE_IMMUTABLE;
 242	if (fsflags & FS_APPEND_FL)
 243		binode_flags |= BTRFS_INODE_APPEND;
 244	else
 245		binode_flags &= ~BTRFS_INODE_APPEND;
 246	if (fsflags & FS_NODUMP_FL)
 247		binode_flags |= BTRFS_INODE_NODUMP;
 248	else
 249		binode_flags &= ~BTRFS_INODE_NODUMP;
 250	if (fsflags & FS_NOATIME_FL)
 251		binode_flags |= BTRFS_INODE_NOATIME;
 252	else
 253		binode_flags &= ~BTRFS_INODE_NOATIME;
 254	if (fsflags & FS_DIRSYNC_FL)
 255		binode_flags |= BTRFS_INODE_DIRSYNC;
 256	else
 257		binode_flags &= ~BTRFS_INODE_DIRSYNC;
 258	if (fsflags & FS_NOCOW_FL) {
 259		if (S_ISREG(inode->i_mode)) {
 260			/*
 261			 * It's safe to turn csums off here, no extents exist.
 262			 * Otherwise we want the flag to reflect the real COW
 263			 * status of the file and will not set it.
 264			 */
 265			if (inode->i_size == 0)
 266				binode_flags |= BTRFS_INODE_NODATACOW |
 267						BTRFS_INODE_NODATASUM;
 268		} else {
 269			binode_flags |= BTRFS_INODE_NODATACOW;
 270		}
 271	} else {
 272		/*
 273		 * Revert back under same assumptions as above
 274		 */
 275		if (S_ISREG(inode->i_mode)) {
 276			if (inode->i_size == 0)
 277				binode_flags &= ~(BTRFS_INODE_NODATACOW |
 278						  BTRFS_INODE_NODATASUM);
 279		} else {
 280			binode_flags &= ~BTRFS_INODE_NODATACOW;
 281		}
 282	}
 283
 284	/*
 285	 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 286	 * flag may be changed automatically if compression code won't make
 287	 * things smaller.
 288	 */
 289	if (fsflags & FS_NOCOMP_FL) {
 290		binode_flags &= ~BTRFS_INODE_COMPRESS;
 291		binode_flags |= BTRFS_INODE_NOCOMPRESS;
 292	} else if (fsflags & FS_COMPR_FL) {
 
 
 
 
 
 293
 294		if (IS_SWAPFILE(inode)) {
 295			ret = -ETXTBSY;
 296			goto out_unlock;
 297		}
 298
 299		binode_flags |= BTRFS_INODE_COMPRESS;
 300		binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
 
 
 
 
 
 
 301
 302		comp = btrfs_compress_type2str(fs_info->compress_type);
 303		if (!comp || comp[0] == 0)
 304			comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
 305	} else {
 306		binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 
 
 
 307	}
 308
 309	/*
 310	 * 1 for inode item
 311	 * 2 for properties
 312	 */
 313	trans = btrfs_start_transaction(root, 3);
 314	if (IS_ERR(trans)) {
 315		ret = PTR_ERR(trans);
 316		goto out_unlock;
 317	}
 318
 319	if (comp) {
 320		ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
 321				     strlen(comp), 0);
 322		if (ret) {
 323			btrfs_abort_transaction(trans, ret);
 324			goto out_end_trans;
 325		}
 326	} else {
 327		ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
 328				     0, 0);
 329		if (ret && ret != -ENODATA) {
 330			btrfs_abort_transaction(trans, ret);
 331			goto out_end_trans;
 332		}
 333	}
 334
 335	binode->flags = binode_flags;
 336	btrfs_sync_inode_flags_to_i_flags(inode);
 337	inode_inc_iversion(inode);
 338	inode->i_ctime = current_time(inode);
 339	ret = btrfs_update_inode(trans, root, inode);
 340
 341 out_end_trans:
 342	btrfs_end_transaction(trans);
 343 out_unlock:
 344	inode_unlock(inode);
 345	mnt_drop_write_file(file);
 346	return ret;
 347}
 348
 349/*
 350 * Translate btrfs internal inode flags to xflags as expected by the
 351 * FS_IOC_FSGETXATT ioctl. Filter only the supported ones, unknown flags are
 352 * silently dropped.
 353 */
 354static unsigned int btrfs_inode_flags_to_xflags(unsigned int flags)
 355{
 356	unsigned int xflags = 0;
 357
 358	if (flags & BTRFS_INODE_APPEND)
 359		xflags |= FS_XFLAG_APPEND;
 360	if (flags & BTRFS_INODE_IMMUTABLE)
 361		xflags |= FS_XFLAG_IMMUTABLE;
 362	if (flags & BTRFS_INODE_NOATIME)
 363		xflags |= FS_XFLAG_NOATIME;
 364	if (flags & BTRFS_INODE_NODUMP)
 365		xflags |= FS_XFLAG_NODUMP;
 366	if (flags & BTRFS_INODE_SYNC)
 367		xflags |= FS_XFLAG_SYNC;
 368
 369	return xflags;
 370}
 371
 372/* Check if @flags are a supported and valid set of FS_XFLAGS_* flags */
 373static int check_xflags(unsigned int flags)
 374{
 375	if (flags & ~(FS_XFLAG_APPEND | FS_XFLAG_IMMUTABLE | FS_XFLAG_NOATIME |
 376		      FS_XFLAG_NODUMP | FS_XFLAG_SYNC))
 377		return -EOPNOTSUPP;
 378	return 0;
 379}
 380
 381/*
 382 * Set the xflags from the internal inode flags. The remaining items of fsxattr
 383 * are zeroed.
 384 */
 385static int btrfs_ioctl_fsgetxattr(struct file *file, void __user *arg)
 386{
 387	struct btrfs_inode *binode = BTRFS_I(file_inode(file));
 388	struct fsxattr fa;
 389
 390	simple_fill_fsxattr(&fa, btrfs_inode_flags_to_xflags(binode->flags));
 391	if (copy_to_user(arg, &fa, sizeof(fa)))
 392		return -EFAULT;
 393
 394	return 0;
 395}
 396
 397static int btrfs_ioctl_fssetxattr(struct file *file, void __user *arg)
 398{
 399	struct inode *inode = file_inode(file);
 400	struct btrfs_inode *binode = BTRFS_I(inode);
 401	struct btrfs_root *root = binode->root;
 402	struct btrfs_trans_handle *trans;
 403	struct fsxattr fa, old_fa;
 404	unsigned old_flags;
 405	unsigned old_i_flags;
 406	int ret = 0;
 407
 408	if (!inode_owner_or_capable(inode))
 409		return -EPERM;
 410
 411	if (btrfs_root_readonly(root))
 412		return -EROFS;
 413
 414	if (copy_from_user(&fa, arg, sizeof(fa)))
 415		return -EFAULT;
 416
 417	ret = check_xflags(fa.fsx_xflags);
 418	if (ret)
 419		return ret;
 420
 421	if (fa.fsx_extsize != 0 || fa.fsx_projid != 0 || fa.fsx_cowextsize != 0)
 422		return -EOPNOTSUPP;
 423
 424	ret = mnt_want_write_file(file);
 425	if (ret)
 426		return ret;
 427
 428	inode_lock(inode);
 429
 430	old_flags = binode->flags;
 431	old_i_flags = inode->i_flags;
 432
 433	simple_fill_fsxattr(&old_fa,
 434			    btrfs_inode_flags_to_xflags(binode->flags));
 435	ret = vfs_ioc_fssetxattr_check(inode, &old_fa, &fa);
 436	if (ret)
 437		goto out_unlock;
 438
 439	if (fa.fsx_xflags & FS_XFLAG_SYNC)
 440		binode->flags |= BTRFS_INODE_SYNC;
 441	else
 442		binode->flags &= ~BTRFS_INODE_SYNC;
 443	if (fa.fsx_xflags & FS_XFLAG_IMMUTABLE)
 444		binode->flags |= BTRFS_INODE_IMMUTABLE;
 445	else
 446		binode->flags &= ~BTRFS_INODE_IMMUTABLE;
 447	if (fa.fsx_xflags & FS_XFLAG_APPEND)
 448		binode->flags |= BTRFS_INODE_APPEND;
 449	else
 450		binode->flags &= ~BTRFS_INODE_APPEND;
 451	if (fa.fsx_xflags & FS_XFLAG_NODUMP)
 452		binode->flags |= BTRFS_INODE_NODUMP;
 453	else
 454		binode->flags &= ~BTRFS_INODE_NODUMP;
 455	if (fa.fsx_xflags & FS_XFLAG_NOATIME)
 456		binode->flags |= BTRFS_INODE_NOATIME;
 457	else
 458		binode->flags &= ~BTRFS_INODE_NOATIME;
 459
 460	/* 1 item for the inode */
 461	trans = btrfs_start_transaction(root, 1);
 462	if (IS_ERR(trans)) {
 463		ret = PTR_ERR(trans);
 464		goto out_unlock;
 465	}
 466
 467	btrfs_sync_inode_flags_to_i_flags(inode);
 468	inode_inc_iversion(inode);
 469	inode->i_ctime = current_time(inode);
 470	ret = btrfs_update_inode(trans, root, inode);
 471
 472	btrfs_end_transaction(trans);
 473
 474out_unlock:
 475	if (ret) {
 476		binode->flags = old_flags;
 477		inode->i_flags = old_i_flags;
 478	}
 479
 
 480	inode_unlock(inode);
 481	mnt_drop_write_file(file);
 482
 483	return ret;
 484}
 485
 486static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 487{
 488	struct inode *inode = file_inode(file);
 489
 490	return put_user(inode->i_generation, arg);
 491}
 492
 493static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
 494					void __user *arg)
 495{
 
 
 496	struct btrfs_device *device;
 497	struct request_queue *q;
 498	struct fstrim_range range;
 499	u64 minlen = ULLONG_MAX;
 500	u64 num_devices = 0;
 
 501	int ret;
 502
 503	if (!capable(CAP_SYS_ADMIN))
 504		return -EPERM;
 505
 506	/*
 507	 * If the fs is mounted with nologreplay, which requires it to be
 508	 * mounted in RO mode as well, we can not allow discard on free space
 509	 * inside block groups, because log trees refer to extents that are not
 510	 * pinned in a block group's free space cache (pinning the extents is
 511	 * precisely the first phase of replaying a log tree).
 512	 */
 513	if (btrfs_test_opt(fs_info, NOLOGREPLAY))
 514		return -EROFS;
 515
 516	rcu_read_lock();
 517	list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 518				dev_list) {
 519		if (!device->bdev)
 520			continue;
 521		q = bdev_get_queue(device->bdev);
 522		if (blk_queue_discard(q)) {
 523			num_devices++;
 524			minlen = min_t(u64, q->limits.discard_granularity,
 525				     minlen);
 526		}
 527	}
 528	rcu_read_unlock();
 529
 530	if (!num_devices)
 531		return -EOPNOTSUPP;
 532	if (copy_from_user(&range, arg, sizeof(range)))
 533		return -EFAULT;
 534
 535	/*
 536	 * NOTE: Don't truncate the range using super->total_bytes.  Bytenr of
 537	 * block group is in the logical address space, which can be any
 538	 * sectorsize aligned bytenr in  the range [0, U64_MAX].
 539	 */
 540	if (range.len < fs_info->sb->s_blocksize)
 541		return -EINVAL;
 542
 
 543	range.minlen = max(range.minlen, minlen);
 544	ret = btrfs_trim_fs(fs_info, &range);
 545	if (ret < 0)
 546		return ret;
 547
 548	if (copy_to_user(arg, &range, sizeof(range)))
 549		return -EFAULT;
 550
 551	return 0;
 552}
 553
 554int __pure btrfs_is_empty_uuid(u8 *uuid)
 555{
 556	int i;
 557
 558	for (i = 0; i < BTRFS_UUID_SIZE; i++) {
 559		if (uuid[i])
 560			return 0;
 561	}
 562	return 1;
 563}
 564
 565static noinline int create_subvol(struct inode *dir,
 566				  struct dentry *dentry,
 567				  const char *name, int namelen,
 
 568				  struct btrfs_qgroup_inherit *inherit)
 569{
 570	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 571	struct btrfs_trans_handle *trans;
 572	struct btrfs_key key;
 573	struct btrfs_root_item *root_item;
 574	struct btrfs_inode_item *inode_item;
 575	struct extent_buffer *leaf;
 576	struct btrfs_root *root = BTRFS_I(dir)->root;
 577	struct btrfs_root *new_root;
 578	struct btrfs_block_rsv block_rsv;
 579	struct timespec64 cur_time = current_time(dir);
 580	struct inode *inode;
 581	int ret;
 582	int err;
 583	dev_t anon_dev = 0;
 584	u64 objectid;
 585	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 586	u64 index = 0;
 
 
 587
 588	root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
 589	if (!root_item)
 590		return -ENOMEM;
 591
 592	ret = btrfs_find_free_objectid(fs_info->tree_root, &objectid);
 593	if (ret)
 594		goto fail_free;
 595
 596	ret = get_anon_bdev(&anon_dev);
 597	if (ret < 0)
 598		goto fail_free;
 599
 600	/*
 601	 * Don't create subvolume whose level is not zero. Or qgroup will be
 602	 * screwed up since it assumes subvolume qgroup's level to be 0.
 603	 */
 604	if (btrfs_qgroup_level(objectid)) {
 605		ret = -ENOSPC;
 606		goto fail_free;
 607	}
 608
 609	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 610	/*
 611	 * The same as the snapshot creation, please see the comment
 612	 * of create_snapshot().
 613	 */
 614	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
 
 615	if (ret)
 616		goto fail_free;
 617
 618	trans = btrfs_start_transaction(root, 0);
 619	if (IS_ERR(trans)) {
 620		ret = PTR_ERR(trans);
 621		btrfs_subvolume_release_metadata(fs_info, &block_rsv);
 
 622		goto fail_free;
 623	}
 624	trans->block_rsv = &block_rsv;
 625	trans->bytes_reserved = block_rsv.size;
 626
 627	ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
 628	if (ret)
 629		goto fail;
 630
 631	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0);
 632	if (IS_ERR(leaf)) {
 633		ret = PTR_ERR(leaf);
 634		goto fail;
 635	}
 636
 
 
 
 
 
 
 
 
 637	btrfs_mark_buffer_dirty(leaf);
 638
 639	inode_item = &root_item->inode;
 640	btrfs_set_stack_inode_generation(inode_item, 1);
 641	btrfs_set_stack_inode_size(inode_item, 3);
 642	btrfs_set_stack_inode_nlink(inode_item, 1);
 643	btrfs_set_stack_inode_nbytes(inode_item,
 644				     fs_info->nodesize);
 645	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 646
 647	btrfs_set_root_flags(root_item, 0);
 648	btrfs_set_root_limit(root_item, 0);
 649	btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 650
 651	btrfs_set_root_bytenr(root_item, leaf->start);
 652	btrfs_set_root_generation(root_item, trans->transid);
 653	btrfs_set_root_level(root_item, 0);
 654	btrfs_set_root_refs(root_item, 1);
 655	btrfs_set_root_used(root_item, leaf->len);
 656	btrfs_set_root_last_snapshot(root_item, 0);
 657
 658	btrfs_set_root_generation_v2(root_item,
 659			btrfs_root_generation(root_item));
 660	generate_random_guid(root_item->uuid);
 
 661	btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
 662	btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
 663	root_item->ctime = root_item->otime;
 664	btrfs_set_root_ctransid(root_item, trans->transid);
 665	btrfs_set_root_otransid(root_item, trans->transid);
 666
 667	btrfs_tree_unlock(leaf);
 668	free_extent_buffer(leaf);
 669	leaf = NULL;
 670
 671	btrfs_set_root_dirid(root_item, new_dirid);
 672
 673	key.objectid = objectid;
 674	key.offset = 0;
 675	key.type = BTRFS_ROOT_ITEM_KEY;
 676	ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
 677				root_item);
 678	if (ret)
 679		goto fail;
 680
 681	key.offset = (u64)-1;
 682	new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
 683	if (IS_ERR(new_root)) {
 684		free_anon_bdev(anon_dev);
 685		ret = PTR_ERR(new_root);
 686		btrfs_abort_transaction(trans, ret);
 687		goto fail;
 688	}
 689	/* Freeing will be done in btrfs_put_root() of new_root */
 690	anon_dev = 0;
 691
 692	btrfs_record_root_in_trans(trans, new_root);
 693
 694	ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
 695	btrfs_put_root(new_root);
 696	if (ret) {
 697		/* We potentially lose an unused inode item here */
 698		btrfs_abort_transaction(trans, ret);
 699		goto fail;
 700	}
 701
 702	mutex_lock(&new_root->objectid_mutex);
 703	new_root->highest_objectid = new_dirid;
 704	mutex_unlock(&new_root->objectid_mutex);
 705
 706	/*
 707	 * insert the directory item
 708	 */
 709	ret = btrfs_set_inode_index(BTRFS_I(dir), &index);
 710	if (ret) {
 711		btrfs_abort_transaction(trans, ret);
 712		goto fail;
 713	}
 714
 715	ret = btrfs_insert_dir_item(trans, name, namelen, BTRFS_I(dir), &key,
 
 716				    BTRFS_FT_DIR, index);
 717	if (ret) {
 718		btrfs_abort_transaction(trans, ret);
 719		goto fail;
 720	}
 721
 722	btrfs_i_size_write(BTRFS_I(dir), dir->i_size + namelen * 2);
 723	ret = btrfs_update_inode(trans, root, dir);
 724	if (ret) {
 725		btrfs_abort_transaction(trans, ret);
 726		goto fail;
 727	}
 728
 729	ret = btrfs_add_root_ref(trans, objectid, root->root_key.objectid,
 730				 btrfs_ino(BTRFS_I(dir)), index, name, namelen);
 731	if (ret) {
 732		btrfs_abort_transaction(trans, ret);
 733		goto fail;
 734	}
 735
 736	ret = btrfs_uuid_tree_add(trans, root_item->uuid,
 737				  BTRFS_UUID_KEY_SUBVOL, objectid);
 738	if (ret)
 739		btrfs_abort_transaction(trans, ret);
 740
 741fail:
 742	kfree(root_item);
 743	trans->block_rsv = NULL;
 744	trans->bytes_reserved = 0;
 745	btrfs_subvolume_release_metadata(fs_info, &block_rsv);
 746
 747	err = btrfs_commit_transaction(trans);
 
 
 
 
 
 
 
 748	if (err && !ret)
 749		ret = err;
 750
 751	if (!ret) {
 752		inode = btrfs_lookup_dentry(dir, dentry);
 753		if (IS_ERR(inode))
 754			return PTR_ERR(inode);
 755		d_instantiate(dentry, inode);
 756	}
 757	return ret;
 758
 759fail_free:
 760	if (anon_dev)
 761		free_anon_bdev(anon_dev);
 762	kfree(root_item);
 763	return ret;
 764}
 765
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 766static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 767			   struct dentry *dentry, bool readonly,
 
 768			   struct btrfs_qgroup_inherit *inherit)
 769{
 770	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 771	struct inode *inode;
 772	struct btrfs_pending_snapshot *pending_snapshot;
 773	struct btrfs_trans_handle *trans;
 774	int ret;
 775
 776	if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
 777		return -EINVAL;
 778
 779	if (atomic_read(&root->nr_swapfiles)) {
 780		btrfs_warn(fs_info,
 781			   "cannot snapshot subvolume with active swapfile");
 782		return -ETXTBSY;
 783	}
 784
 785	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
 786	if (!pending_snapshot)
 787		return -ENOMEM;
 788
 789	ret = get_anon_bdev(&pending_snapshot->anon_dev);
 790	if (ret < 0)
 791		goto free_pending;
 792	pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
 793			GFP_KERNEL);
 794	pending_snapshot->path = btrfs_alloc_path();
 795	if (!pending_snapshot->root_item || !pending_snapshot->path) {
 796		ret = -ENOMEM;
 797		goto free_pending;
 798	}
 799
 
 
 
 
 
 
 
 
 
 
 800	btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 801			     BTRFS_BLOCK_RSV_TEMP);
 802	/*
 803	 * 1 - parent dir inode
 804	 * 2 - dir entries
 805	 * 1 - root item
 806	 * 2 - root ref/backref
 807	 * 1 - root of snapshot
 808	 * 1 - UUID item
 809	 */
 810	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 811					&pending_snapshot->block_rsv, 8,
 
 812					false);
 813	if (ret)
 814		goto free_pending;
 815
 816	pending_snapshot->dentry = dentry;
 817	pending_snapshot->root = root;
 818	pending_snapshot->readonly = readonly;
 819	pending_snapshot->dir = dir;
 820	pending_snapshot->inherit = inherit;
 821
 822	trans = btrfs_start_transaction(root, 0);
 823	if (IS_ERR(trans)) {
 824		ret = PTR_ERR(trans);
 825		goto fail;
 826	}
 827
 828	spin_lock(&fs_info->trans_lock);
 829	list_add(&pending_snapshot->list,
 830		 &trans->transaction->pending_snapshots);
 831	spin_unlock(&fs_info->trans_lock);
 832
 833	ret = btrfs_commit_transaction(trans);
 
 
 
 
 
 
 834	if (ret)
 835		goto fail;
 836
 837	ret = pending_snapshot->error;
 838	if (ret)
 839		goto fail;
 840
 841	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 842	if (ret)
 843		goto fail;
 844
 845	inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
 846	if (IS_ERR(inode)) {
 847		ret = PTR_ERR(inode);
 848		goto fail;
 849	}
 850
 851	d_instantiate(dentry, inode);
 852	ret = 0;
 853	pending_snapshot->anon_dev = 0;
 854fail:
 855	/* Prevent double freeing of anon_dev */
 856	if (ret && pending_snapshot->snap)
 857		pending_snapshot->snap->anon_dev = 0;
 858	btrfs_put_root(pending_snapshot->snap);
 859	btrfs_subvolume_release_metadata(fs_info, &pending_snapshot->block_rsv);
 
 860free_pending:
 861	if (pending_snapshot->anon_dev)
 862		free_anon_bdev(pending_snapshot->anon_dev);
 863	kfree(pending_snapshot->root_item);
 864	btrfs_free_path(pending_snapshot->path);
 865	kfree(pending_snapshot);
 866
 867	return ret;
 868}
 869
 870/*  copy of may_delete in fs/namei.c()
 871 *	Check whether we can remove a link victim from directory dir, check
 872 *  whether the type of victim is right.
 873 *  1. We can't do it if dir is read-only (done in permission())
 874 *  2. We should have write and exec permissions on dir
 875 *  3. We can't remove anything from append-only dir
 876 *  4. We can't do anything with immutable dir (done in permission())
 877 *  5. If the sticky bit on dir is set we should either
 878 *	a. be owner of dir, or
 879 *	b. be owner of victim, or
 880 *	c. have CAP_FOWNER capability
 881 *  6. If the victim is append-only or immutable we can't do anything with
 882 *     links pointing to it.
 883 *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 884 *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 885 *  9. We can't remove a root or mountpoint.
 886 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 887 *     nfs_async_unlink().
 888 */
 889
 890static int btrfs_may_delete(struct inode *dir, struct dentry *victim, int isdir)
 891{
 892	int error;
 893
 894	if (d_really_is_negative(victim))
 895		return -ENOENT;
 896
 897	BUG_ON(d_inode(victim->d_parent) != dir);
 898	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 899
 900	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 901	if (error)
 902		return error;
 903	if (IS_APPEND(dir))
 904		return -EPERM;
 905	if (check_sticky(dir, d_inode(victim)) || IS_APPEND(d_inode(victim)) ||
 906	    IS_IMMUTABLE(d_inode(victim)) || IS_SWAPFILE(d_inode(victim)))
 907		return -EPERM;
 908	if (isdir) {
 909		if (!d_is_dir(victim))
 910			return -ENOTDIR;
 911		if (IS_ROOT(victim))
 912			return -EBUSY;
 913	} else if (d_is_dir(victim))
 914		return -EISDIR;
 915	if (IS_DEADDIR(dir))
 916		return -ENOENT;
 917	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 918		return -EBUSY;
 919	return 0;
 920}
 921
 922/* copy of may_create in fs/namei.c() */
 923static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 924{
 925	if (d_really_is_positive(child))
 926		return -EEXIST;
 927	if (IS_DEADDIR(dir))
 928		return -ENOENT;
 929	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 930}
 931
 932/*
 933 * Create a new subvolume below @parent.  This is largely modeled after
 934 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 935 * inside this filesystem so it's quite a bit simpler.
 936 */
 937static noinline int btrfs_mksubvol(const struct path *parent,
 938				   const char *name, int namelen,
 939				   struct btrfs_root *snap_src,
 940				   bool readonly,
 941				   struct btrfs_qgroup_inherit *inherit)
 942{
 943	struct inode *dir = d_inode(parent->dentry);
 944	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 945	struct dentry *dentry;
 946	int error;
 947
 948	error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
 949	if (error == -EINTR)
 950		return error;
 951
 952	dentry = lookup_one_len(name, parent->dentry, namelen);
 953	error = PTR_ERR(dentry);
 954	if (IS_ERR(dentry))
 955		goto out_unlock;
 956
 957	error = btrfs_may_create(dir, dentry);
 958	if (error)
 959		goto out_dput;
 960
 961	/*
 962	 * even if this name doesn't exist, we may get hash collisions.
 963	 * check for them now when we can safely fail
 964	 */
 965	error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 966					       dir->i_ino, name,
 967					       namelen);
 968	if (error)
 969		goto out_dput;
 970
 971	down_read(&fs_info->subvol_sem);
 972
 973	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 974		goto out_up_read;
 975
 976	if (snap_src)
 977		error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
 978	else
 979		error = create_subvol(dir, dentry, name, namelen, inherit);
 980
 
 
 981	if (!error)
 982		fsnotify_mkdir(dir, dentry);
 983out_up_read:
 984	up_read(&fs_info->subvol_sem);
 985out_dput:
 986	dput(dentry);
 987out_unlock:
 988	inode_unlock(dir);
 989	return error;
 990}
 991
 992static noinline int btrfs_mksnapshot(const struct path *parent,
 993				   const char *name, int namelen,
 994				   struct btrfs_root *root,
 995				   bool readonly,
 996				   struct btrfs_qgroup_inherit *inherit)
 997{
 998	int ret;
 999	bool snapshot_force_cow = false;
1000
1001	/*
1002	 * Force new buffered writes to reserve space even when NOCOW is
1003	 * possible. This is to avoid later writeback (running dealloc) to
1004	 * fallback to COW mode and unexpectedly fail with ENOSPC.
1005	 */
1006	btrfs_drew_read_lock(&root->snapshot_lock);
1007
1008	ret = btrfs_start_delalloc_snapshot(root);
1009	if (ret)
1010		goto out;
1011
1012	/*
1013	 * All previous writes have started writeback in NOCOW mode, so now
1014	 * we force future writes to fallback to COW mode during snapshot
1015	 * creation.
1016	 */
1017	atomic_inc(&root->snapshot_force_cow);
1018	snapshot_force_cow = true;
1019
1020	btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
1021
1022	ret = btrfs_mksubvol(parent, name, namelen,
1023			     root, readonly, inherit);
1024out:
1025	if (snapshot_force_cow)
1026		atomic_dec(&root->snapshot_force_cow);
1027	btrfs_drew_read_unlock(&root->snapshot_lock);
1028	return ret;
1029}
1030
1031/*
1032 * When we're defragging a range, we don't want to kick it off again
1033 * if it is really just waiting for delalloc to send it down.
1034 * If we find a nice big extent or delalloc range for the bytes in the
1035 * file you want to defrag, we return 0 to let you know to skip this
1036 * part of the file
1037 */
1038static int check_defrag_in_cache(struct inode *inode, u64 offset, u32 thresh)
1039{
1040	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1041	struct extent_map *em = NULL;
1042	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1043	u64 end;
1044
1045	read_lock(&em_tree->lock);
1046	em = lookup_extent_mapping(em_tree, offset, PAGE_SIZE);
1047	read_unlock(&em_tree->lock);
1048
1049	if (em) {
1050		end = extent_map_end(em);
1051		free_extent_map(em);
1052		if (end - offset > thresh)
1053			return 0;
1054	}
1055	/* if we already have a nice delalloc here, just stop */
1056	thresh /= 2;
1057	end = count_range_bits(io_tree, &offset, offset + thresh,
1058			       thresh, EXTENT_DELALLOC, 1);
1059	if (end >= thresh)
1060		return 0;
1061	return 1;
1062}
1063
1064/*
1065 * helper function to walk through a file and find extents
1066 * newer than a specific transid, and smaller than thresh.
1067 *
1068 * This is used by the defragging code to find new and small
1069 * extents
1070 */
1071static int find_new_extents(struct btrfs_root *root,
1072			    struct inode *inode, u64 newer_than,
1073			    u64 *off, u32 thresh)
1074{
1075	struct btrfs_path *path;
1076	struct btrfs_key min_key;
1077	struct extent_buffer *leaf;
1078	struct btrfs_file_extent_item *extent;
1079	int type;
1080	int ret;
1081	u64 ino = btrfs_ino(BTRFS_I(inode));
1082
1083	path = btrfs_alloc_path();
1084	if (!path)
1085		return -ENOMEM;
1086
1087	min_key.objectid = ino;
1088	min_key.type = BTRFS_EXTENT_DATA_KEY;
1089	min_key.offset = *off;
1090
1091	while (1) {
1092		ret = btrfs_search_forward(root, &min_key, path, newer_than);
1093		if (ret != 0)
1094			goto none;
1095process_slot:
1096		if (min_key.objectid != ino)
1097			goto none;
1098		if (min_key.type != BTRFS_EXTENT_DATA_KEY)
1099			goto none;
1100
1101		leaf = path->nodes[0];
1102		extent = btrfs_item_ptr(leaf, path->slots[0],
1103					struct btrfs_file_extent_item);
1104
1105		type = btrfs_file_extent_type(leaf, extent);
1106		if (type == BTRFS_FILE_EXTENT_REG &&
1107		    btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
1108		    check_defrag_in_cache(inode, min_key.offset, thresh)) {
1109			*off = min_key.offset;
1110			btrfs_free_path(path);
1111			return 0;
1112		}
1113
1114		path->slots[0]++;
1115		if (path->slots[0] < btrfs_header_nritems(leaf)) {
1116			btrfs_item_key_to_cpu(leaf, &min_key, path->slots[0]);
1117			goto process_slot;
1118		}
1119
1120		if (min_key.offset == (u64)-1)
1121			goto none;
1122
1123		min_key.offset++;
1124		btrfs_release_path(path);
1125	}
1126none:
1127	btrfs_free_path(path);
1128	return -ENOENT;
1129}
1130
1131static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
1132{
1133	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
1134	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
1135	struct extent_map *em;
1136	u64 len = PAGE_SIZE;
1137
1138	/*
1139	 * hopefully we have this extent in the tree already, try without
1140	 * the full extent lock
1141	 */
1142	read_lock(&em_tree->lock);
1143	em = lookup_extent_mapping(em_tree, start, len);
1144	read_unlock(&em_tree->lock);
1145
1146	if (!em) {
1147		struct extent_state *cached = NULL;
1148		u64 end = start + len - 1;
1149
1150		/* get the big lock and read metadata off disk */
1151		lock_extent_bits(io_tree, start, end, &cached);
1152		em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len);
1153		unlock_extent_cached(io_tree, start, end, &cached);
1154
1155		if (IS_ERR(em))
1156			return NULL;
1157	}
1158
1159	return em;
1160}
1161
1162static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
1163{
1164	struct extent_map *next;
1165	bool ret = true;
1166
1167	/* this is the last extent */
1168	if (em->start + em->len >= i_size_read(inode))
1169		return false;
1170
1171	next = defrag_lookup_extent(inode, em->start + em->len);
1172	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
1173		ret = false;
1174	else if ((em->block_start + em->block_len == next->block_start) &&
1175		 (em->block_len > SZ_128K && next->block_len > SZ_128K))
1176		ret = false;
1177
1178	free_extent_map(next);
1179	return ret;
1180}
1181
1182static int should_defrag_range(struct inode *inode, u64 start, u32 thresh,
1183			       u64 *last_len, u64 *skip, u64 *defrag_end,
1184			       int compress)
1185{
1186	struct extent_map *em;
1187	int ret = 1;
1188	bool next_mergeable = true;
1189	bool prev_mergeable = true;
1190
1191	/*
1192	 * make sure that once we start defragging an extent, we keep on
1193	 * defragging it
1194	 */
1195	if (start < *defrag_end)
1196		return 1;
1197
1198	*skip = 0;
1199
1200	em = defrag_lookup_extent(inode, start);
1201	if (!em)
1202		return 0;
1203
1204	/* this will cover holes, and inline extents */
1205	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
1206		ret = 0;
1207		goto out;
1208	}
1209
1210	if (!*defrag_end)
1211		prev_mergeable = false;
1212
1213	next_mergeable = defrag_check_next_extent(inode, em);
1214	/*
1215	 * we hit a real extent, if it is big or the next extent is not a
1216	 * real extent, don't bother defragging it
1217	 */
1218	if (!compress && (*last_len == 0 || *last_len >= thresh) &&
1219	    (em->len >= thresh || (!next_mergeable && !prev_mergeable)))
1220		ret = 0;
1221out:
1222	/*
1223	 * last_len ends up being a counter of how many bytes we've defragged.
1224	 * every time we choose not to defrag an extent, we reset *last_len
1225	 * so that the next tiny extent will force a defrag.
1226	 *
1227	 * The end result of this is that tiny extents before a single big
1228	 * extent will force at least part of that big extent to be defragged.
1229	 */
1230	if (ret) {
1231		*defrag_end = extent_map_end(em);
1232	} else {
1233		*last_len = 0;
1234		*skip = extent_map_end(em);
1235		*defrag_end = 0;
1236	}
1237
1238	free_extent_map(em);
1239	return ret;
1240}
1241
1242/*
1243 * it doesn't do much good to defrag one or two pages
1244 * at a time.  This pulls in a nice chunk of pages
1245 * to COW and defrag.
1246 *
1247 * It also makes sure the delalloc code has enough
1248 * dirty data to avoid making new small extents as part
1249 * of the defrag
1250 *
1251 * It's a good idea to start RA on this range
1252 * before calling this.
1253 */
1254static int cluster_pages_for_defrag(struct inode *inode,
1255				    struct page **pages,
1256				    unsigned long start_index,
1257				    unsigned long num_pages)
1258{
1259	unsigned long file_end;
1260	u64 isize = i_size_read(inode);
1261	u64 page_start;
1262	u64 page_end;
1263	u64 page_cnt;
1264	int ret;
1265	int i;
1266	int i_done;
1267	struct btrfs_ordered_extent *ordered;
1268	struct extent_state *cached_state = NULL;
1269	struct extent_io_tree *tree;
1270	struct extent_changeset *data_reserved = NULL;
1271	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
1272
1273	file_end = (isize - 1) >> PAGE_SHIFT;
1274	if (!isize || start_index > file_end)
1275		return 0;
1276
1277	page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
1278
1279	ret = btrfs_delalloc_reserve_space(BTRFS_I(inode), &data_reserved,
1280			start_index << PAGE_SHIFT,
1281			page_cnt << PAGE_SHIFT);
1282	if (ret)
1283		return ret;
1284	i_done = 0;
1285	tree = &BTRFS_I(inode)->io_tree;
1286
1287	/* step one, lock all the pages */
1288	for (i = 0; i < page_cnt; i++) {
1289		struct page *page;
1290again:
1291		page = find_or_create_page(inode->i_mapping,
1292					   start_index + i, mask);
1293		if (!page)
1294			break;
1295
1296		page_start = page_offset(page);
1297		page_end = page_start + PAGE_SIZE - 1;
1298		while (1) {
1299			lock_extent_bits(tree, page_start, page_end,
1300					 &cached_state);
1301			ordered = btrfs_lookup_ordered_extent(BTRFS_I(inode),
1302							      page_start);
1303			unlock_extent_cached(tree, page_start, page_end,
1304					     &cached_state);
1305			if (!ordered)
1306				break;
1307
1308			unlock_page(page);
1309			btrfs_start_ordered_extent(inode, ordered, 1);
1310			btrfs_put_ordered_extent(ordered);
1311			lock_page(page);
1312			/*
1313			 * we unlocked the page above, so we need check if
1314			 * it was released or not.
1315			 */
1316			if (page->mapping != inode->i_mapping) {
1317				unlock_page(page);
1318				put_page(page);
1319				goto again;
1320			}
1321		}
1322
1323		if (!PageUptodate(page)) {
1324			btrfs_readpage(NULL, page);
1325			lock_page(page);
1326			if (!PageUptodate(page)) {
1327				unlock_page(page);
1328				put_page(page);
1329				ret = -EIO;
1330				break;
1331			}
1332		}
1333
1334		if (page->mapping != inode->i_mapping) {
1335			unlock_page(page);
1336			put_page(page);
1337			goto again;
1338		}
1339
1340		pages[i] = page;
1341		i_done++;
1342	}
1343	if (!i_done || ret)
1344		goto out;
1345
1346	if (!(inode->i_sb->s_flags & SB_ACTIVE))
1347		goto out;
1348
1349	/*
1350	 * so now we have a nice long stream of locked
1351	 * and up to date pages, lets wait on them
1352	 */
1353	for (i = 0; i < i_done; i++)
1354		wait_on_page_writeback(pages[i]);
1355
1356	page_start = page_offset(pages[0]);
1357	page_end = page_offset(pages[i_done - 1]) + PAGE_SIZE;
1358
1359	lock_extent_bits(&BTRFS_I(inode)->io_tree,
1360			 page_start, page_end - 1, &cached_state);
1361	clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1362			  page_end - 1, EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING |
1363			  EXTENT_DEFRAG, 0, 0, &cached_state);
 
1364
1365	if (i_done != page_cnt) {
1366		spin_lock(&BTRFS_I(inode)->lock);
1367		btrfs_mod_outstanding_extents(BTRFS_I(inode), 1);
1368		spin_unlock(&BTRFS_I(inode)->lock);
1369		btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved,
1370				start_index << PAGE_SHIFT,
1371				(page_cnt - i_done) << PAGE_SHIFT, true);
1372	}
1373
1374
1375	set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
1376			  &cached_state);
1377
1378	unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1379			     page_start, page_end - 1, &cached_state);
 
1380
1381	for (i = 0; i < i_done; i++) {
1382		clear_page_dirty_for_io(pages[i]);
1383		ClearPageChecked(pages[i]);
1384		set_page_extent_mapped(pages[i]);
1385		set_page_dirty(pages[i]);
1386		unlock_page(pages[i]);
1387		put_page(pages[i]);
1388	}
1389	btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1390	extent_changeset_free(data_reserved);
1391	return i_done;
1392out:
1393	for (i = 0; i < i_done; i++) {
1394		unlock_page(pages[i]);
1395		put_page(pages[i]);
1396	}
1397	btrfs_delalloc_release_space(BTRFS_I(inode), data_reserved,
1398			start_index << PAGE_SHIFT,
1399			page_cnt << PAGE_SHIFT, true);
1400	btrfs_delalloc_release_extents(BTRFS_I(inode), page_cnt << PAGE_SHIFT);
1401	extent_changeset_free(data_reserved);
1402	return ret;
1403
1404}
1405
1406int btrfs_defrag_file(struct inode *inode, struct file *file,
1407		      struct btrfs_ioctl_defrag_range_args *range,
1408		      u64 newer_than, unsigned long max_to_defrag)
1409{
1410	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1411	struct btrfs_root *root = BTRFS_I(inode)->root;
1412	struct file_ra_state *ra = NULL;
1413	unsigned long last_index;
1414	u64 isize = i_size_read(inode);
1415	u64 last_len = 0;
1416	u64 skip = 0;
1417	u64 defrag_end = 0;
1418	u64 newer_off = range->start;
1419	unsigned long i;
1420	unsigned long ra_index = 0;
1421	int ret;
1422	int defrag_count = 0;
1423	int compress_type = BTRFS_COMPRESS_ZLIB;
1424	u32 extent_thresh = range->extent_thresh;
1425	unsigned long max_cluster = SZ_256K >> PAGE_SHIFT;
1426	unsigned long cluster = max_cluster;
1427	u64 new_align = ~((u64)SZ_128K - 1);
1428	struct page **pages = NULL;
1429	bool do_compress = range->flags & BTRFS_DEFRAG_RANGE_COMPRESS;
1430
1431	if (isize == 0)
1432		return 0;
1433
1434	if (range->start >= isize)
1435		return -EINVAL;
1436
1437	if (do_compress) {
1438		if (range->compress_type >= BTRFS_NR_COMPRESS_TYPES)
1439			return -EINVAL;
1440		if (range->compress_type)
1441			compress_type = range->compress_type;
1442	}
1443
1444	if (extent_thresh == 0)
1445		extent_thresh = SZ_256K;
1446
1447	/*
1448	 * If we were not given a file, allocate a readahead context. As
1449	 * readahead is just an optimization, defrag will work without it so
1450	 * we don't error out.
1451	 */
1452	if (!file) {
1453		ra = kzalloc(sizeof(*ra), GFP_KERNEL);
1454		if (ra)
1455			file_ra_state_init(ra, inode->i_mapping);
 
1456	} else {
1457		ra = &file->f_ra;
1458	}
1459
1460	pages = kmalloc_array(max_cluster, sizeof(struct page *), GFP_KERNEL);
 
1461	if (!pages) {
1462		ret = -ENOMEM;
1463		goto out_ra;
1464	}
1465
1466	/* find the last page to defrag */
1467	if (range->start + range->len > range->start) {
1468		last_index = min_t(u64, isize - 1,
1469			 range->start + range->len - 1) >> PAGE_SHIFT;
1470	} else {
1471		last_index = (isize - 1) >> PAGE_SHIFT;
1472	}
1473
1474	if (newer_than) {
1475		ret = find_new_extents(root, inode, newer_than,
1476				       &newer_off, SZ_64K);
1477		if (!ret) {
1478			range->start = newer_off;
1479			/*
1480			 * we always align our defrag to help keep
1481			 * the extents in the file evenly spaced
1482			 */
1483			i = (newer_off & new_align) >> PAGE_SHIFT;
1484		} else
1485			goto out_ra;
1486	} else {
1487		i = range->start >> PAGE_SHIFT;
1488	}
1489	if (!max_to_defrag)
1490		max_to_defrag = last_index - i + 1;
1491
1492	/*
1493	 * make writeback starts from i, so the defrag range can be
1494	 * written sequentially.
1495	 */
1496	if (i < inode->i_mapping->writeback_index)
1497		inode->i_mapping->writeback_index = i;
1498
1499	while (i <= last_index && defrag_count < max_to_defrag &&
1500	       (i < DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE))) {
1501		/*
1502		 * make sure we stop running if someone unmounts
1503		 * the FS
1504		 */
1505		if (!(inode->i_sb->s_flags & SB_ACTIVE))
1506			break;
1507
1508		if (btrfs_defrag_cancelled(fs_info)) {
1509			btrfs_debug(fs_info, "defrag_file cancelled");
1510			ret = -EAGAIN;
1511			break;
1512		}
1513
1514		if (!should_defrag_range(inode, (u64)i << PAGE_SHIFT,
1515					 extent_thresh, &last_len, &skip,
1516					 &defrag_end, do_compress)){
 
1517			unsigned long next;
1518			/*
1519			 * the should_defrag function tells us how much to skip
1520			 * bump our counter by the suggested amount
1521			 */
1522			next = DIV_ROUND_UP(skip, PAGE_SIZE);
1523			i = max(i + 1, next);
1524			continue;
1525		}
1526
1527		if (!newer_than) {
1528			cluster = (PAGE_ALIGN(defrag_end) >>
1529				   PAGE_SHIFT) - i;
1530			cluster = min(cluster, max_cluster);
1531		} else {
1532			cluster = max_cluster;
1533		}
1534
1535		if (i + cluster > ra_index) {
1536			ra_index = max(i, ra_index);
1537			if (ra)
1538				page_cache_sync_readahead(inode->i_mapping, ra,
1539						file, ra_index, cluster);
1540			ra_index += cluster;
1541		}
1542
1543		inode_lock(inode);
1544		if (IS_SWAPFILE(inode)) {
1545			ret = -ETXTBSY;
1546		} else {
1547			if (do_compress)
1548				BTRFS_I(inode)->defrag_compress = compress_type;
1549			ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1550		}
1551		if (ret < 0) {
1552			inode_unlock(inode);
1553			goto out_ra;
1554		}
1555
1556		defrag_count += ret;
1557		balance_dirty_pages_ratelimited(inode->i_mapping);
1558		inode_unlock(inode);
1559
1560		if (newer_than) {
1561			if (newer_off == (u64)-1)
1562				break;
1563
1564			if (ret > 0)
1565				i += ret;
1566
1567			newer_off = max(newer_off + 1,
1568					(u64)i << PAGE_SHIFT);
1569
1570			ret = find_new_extents(root, inode, newer_than,
1571					       &newer_off, SZ_64K);
1572			if (!ret) {
1573				range->start = newer_off;
1574				i = (newer_off & new_align) >> PAGE_SHIFT;
1575			} else {
1576				break;
1577			}
1578		} else {
1579			if (ret > 0) {
1580				i += ret;
1581				last_len += ret << PAGE_SHIFT;
1582			} else {
1583				i++;
1584				last_len = 0;
1585			}
1586		}
1587	}
1588
1589	if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO)) {
1590		filemap_flush(inode->i_mapping);
1591		if (test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT,
1592			     &BTRFS_I(inode)->runtime_flags))
1593			filemap_flush(inode->i_mapping);
1594	}
1595
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1596	if (range->compress_type == BTRFS_COMPRESS_LZO) {
1597		btrfs_set_fs_incompat(fs_info, COMPRESS_LZO);
1598	} else if (range->compress_type == BTRFS_COMPRESS_ZSTD) {
1599		btrfs_set_fs_incompat(fs_info, COMPRESS_ZSTD);
1600	}
1601
1602	ret = defrag_count;
1603
1604out_ra:
1605	if (do_compress) {
1606		inode_lock(inode);
1607		BTRFS_I(inode)->defrag_compress = BTRFS_COMPRESS_NONE;
1608		inode_unlock(inode);
1609	}
1610	if (!file)
1611		kfree(ra);
1612	kfree(pages);
1613	return ret;
1614}
1615
1616static noinline int btrfs_ioctl_resize(struct file *file,
1617					void __user *arg)
1618{
1619	struct inode *inode = file_inode(file);
1620	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1621	u64 new_size;
1622	u64 old_size;
1623	u64 devid = 1;
1624	struct btrfs_root *root = BTRFS_I(inode)->root;
1625	struct btrfs_ioctl_vol_args *vol_args;
1626	struct btrfs_trans_handle *trans;
1627	struct btrfs_device *device = NULL;
1628	char *sizestr;
1629	char *retptr;
1630	char *devstr = NULL;
1631	int ret = 0;
1632	int mod = 0;
1633
1634	if (!capable(CAP_SYS_ADMIN))
1635		return -EPERM;
1636
1637	ret = mnt_want_write_file(file);
1638	if (ret)
1639		return ret;
1640
1641	if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
1642		mnt_drop_write_file(file);
1643		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1644	}
1645
 
1646	vol_args = memdup_user(arg, sizeof(*vol_args));
1647	if (IS_ERR(vol_args)) {
1648		ret = PTR_ERR(vol_args);
1649		goto out;
1650	}
1651
1652	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1653
1654	sizestr = vol_args->name;
1655	devstr = strchr(sizestr, ':');
1656	if (devstr) {
1657		sizestr = devstr + 1;
1658		*devstr = '\0';
1659		devstr = vol_args->name;
1660		ret = kstrtoull(devstr, 10, &devid);
1661		if (ret)
1662			goto out_free;
1663		if (!devid) {
1664			ret = -EINVAL;
1665			goto out_free;
1666		}
1667		btrfs_info(fs_info, "resizing devid %llu", devid);
1668	}
1669
1670	device = btrfs_find_device(fs_info->fs_devices, devid, NULL, NULL, true);
1671	if (!device) {
1672		btrfs_info(fs_info, "resizer unable to find device %llu",
1673			   devid);
1674		ret = -ENODEV;
1675		goto out_free;
1676	}
1677
1678	if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1679		btrfs_info(fs_info,
1680			   "resizer unable to apply on readonly device %llu",
1681		       devid);
1682		ret = -EPERM;
1683		goto out_free;
1684	}
1685
1686	if (!strcmp(sizestr, "max"))
1687		new_size = device->bdev->bd_inode->i_size;
1688	else {
1689		if (sizestr[0] == '-') {
1690			mod = -1;
1691			sizestr++;
1692		} else if (sizestr[0] == '+') {
1693			mod = 1;
1694			sizestr++;
1695		}
1696		new_size = memparse(sizestr, &retptr);
1697		if (*retptr != '\0' || new_size == 0) {
1698			ret = -EINVAL;
1699			goto out_free;
1700		}
1701	}
1702
1703	if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1704		ret = -EPERM;
1705		goto out_free;
1706	}
1707
1708	old_size = btrfs_device_get_total_bytes(device);
1709
1710	if (mod < 0) {
1711		if (new_size > old_size) {
1712			ret = -EINVAL;
1713			goto out_free;
1714		}
1715		new_size = old_size - new_size;
1716	} else if (mod > 0) {
1717		if (new_size > ULLONG_MAX - old_size) {
1718			ret = -ERANGE;
1719			goto out_free;
1720		}
1721		new_size = old_size + new_size;
1722	}
1723
1724	if (new_size < SZ_256M) {
1725		ret = -EINVAL;
1726		goto out_free;
1727	}
1728	if (new_size > device->bdev->bd_inode->i_size) {
1729		ret = -EFBIG;
1730		goto out_free;
1731	}
1732
1733	new_size = round_down(new_size, fs_info->sectorsize);
 
 
 
 
1734
1735	if (new_size > old_size) {
1736		trans = btrfs_start_transaction(root, 0);
1737		if (IS_ERR(trans)) {
1738			ret = PTR_ERR(trans);
1739			goto out_free;
1740		}
1741		ret = btrfs_grow_device(trans, device, new_size);
1742		btrfs_commit_transaction(trans);
1743	} else if (new_size < old_size) {
1744		ret = btrfs_shrink_device(device, new_size);
1745	} /* equal, nothing need to do */
1746
1747	if (ret == 0 && new_size != old_size)
1748		btrfs_info_in_rcu(fs_info,
1749			"resize device %s (devid %llu) from %llu to %llu",
1750			rcu_str_deref(device->name), device->devid,
1751			old_size, new_size);
1752out_free:
1753	kfree(vol_args);
1754out:
1755	clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
 
1756	mnt_drop_write_file(file);
1757	return ret;
1758}
1759
1760static noinline int __btrfs_ioctl_snap_create(struct file *file,
1761				const char *name, unsigned long fd, int subvol,
1762				bool readonly,
1763				struct btrfs_qgroup_inherit *inherit)
1764{
1765	int namelen;
1766	int ret = 0;
1767
1768	if (!S_ISDIR(file_inode(file)->i_mode))
1769		return -ENOTDIR;
1770
1771	ret = mnt_want_write_file(file);
1772	if (ret)
1773		goto out;
1774
1775	namelen = strlen(name);
1776	if (strchr(name, '/')) {
1777		ret = -EINVAL;
1778		goto out_drop_write;
1779	}
1780
1781	if (name[0] == '.' &&
1782	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1783		ret = -EEXIST;
1784		goto out_drop_write;
1785	}
1786
1787	if (subvol) {
1788		ret = btrfs_mksubvol(&file->f_path, name, namelen,
1789				     NULL, readonly, inherit);
1790	} else {
1791		struct fd src = fdget(fd);
1792		struct inode *src_inode;
1793		if (!src.file) {
1794			ret = -EINVAL;
1795			goto out_drop_write;
1796		}
1797
1798		src_inode = file_inode(src.file);
1799		if (src_inode->i_sb != file_inode(file)->i_sb) {
1800			btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1801				   "Snapshot src from another FS");
1802			ret = -EXDEV;
1803		} else if (!inode_owner_or_capable(src_inode)) {
1804			/*
1805			 * Subvolume creation is not restricted, but snapshots
1806			 * are limited to own subvolumes only
1807			 */
1808			ret = -EPERM;
1809		} else {
1810			ret = btrfs_mksnapshot(&file->f_path, name, namelen,
1811					     BTRFS_I(src_inode)->root,
1812					     readonly, inherit);
1813		}
1814		fdput(src);
1815	}
1816out_drop_write:
1817	mnt_drop_write_file(file);
1818out:
1819	return ret;
1820}
1821
1822static noinline int btrfs_ioctl_snap_create(struct file *file,
1823					    void __user *arg, int subvol)
1824{
1825	struct btrfs_ioctl_vol_args *vol_args;
1826	int ret;
1827
1828	if (!S_ISDIR(file_inode(file)->i_mode))
1829		return -ENOTDIR;
1830
1831	vol_args = memdup_user(arg, sizeof(*vol_args));
1832	if (IS_ERR(vol_args))
1833		return PTR_ERR(vol_args);
1834	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1835
1836	ret = __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd,
1837					subvol, false, NULL);
 
1838
1839	kfree(vol_args);
1840	return ret;
1841}
1842
1843static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1844					       void __user *arg, int subvol)
1845{
1846	struct btrfs_ioctl_vol_args_v2 *vol_args;
1847	int ret;
 
 
1848	bool readonly = false;
1849	struct btrfs_qgroup_inherit *inherit = NULL;
1850
1851	if (!S_ISDIR(file_inode(file)->i_mode))
1852		return -ENOTDIR;
1853
1854	vol_args = memdup_user(arg, sizeof(*vol_args));
1855	if (IS_ERR(vol_args))
1856		return PTR_ERR(vol_args);
1857	vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1858
1859	if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
 
 
1860		ret = -EOPNOTSUPP;
1861		goto free_args;
1862	}
1863
 
 
1864	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1865		readonly = true;
1866	if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1867		if (vol_args->size > PAGE_SIZE) {
1868			ret = -EINVAL;
1869			goto free_args;
1870		}
1871		inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1872		if (IS_ERR(inherit)) {
1873			ret = PTR_ERR(inherit);
1874			goto free_args;
1875		}
1876	}
1877
1878	ret = __btrfs_ioctl_snap_create(file, vol_args->name, vol_args->fd,
1879					subvol, readonly, inherit);
 
1880	if (ret)
1881		goto free_inherit;
 
 
 
 
 
 
 
1882free_inherit:
1883	kfree(inherit);
1884free_args:
1885	kfree(vol_args);
1886	return ret;
1887}
1888
1889static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1890						void __user *arg)
1891{
1892	struct inode *inode = file_inode(file);
1893	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1894	struct btrfs_root *root = BTRFS_I(inode)->root;
1895	int ret = 0;
1896	u64 flags = 0;
1897
1898	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1899		return -EINVAL;
1900
1901	down_read(&fs_info->subvol_sem);
1902	if (btrfs_root_readonly(root))
1903		flags |= BTRFS_SUBVOL_RDONLY;
1904	up_read(&fs_info->subvol_sem);
1905
1906	if (copy_to_user(arg, &flags, sizeof(flags)))
1907		ret = -EFAULT;
1908
1909	return ret;
1910}
1911
1912static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1913					      void __user *arg)
1914{
1915	struct inode *inode = file_inode(file);
1916	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1917	struct btrfs_root *root = BTRFS_I(inode)->root;
1918	struct btrfs_trans_handle *trans;
1919	u64 root_flags;
1920	u64 flags;
1921	int ret = 0;
1922
1923	if (!inode_owner_or_capable(inode))
1924		return -EPERM;
1925
1926	ret = mnt_want_write_file(file);
1927	if (ret)
1928		goto out;
1929
1930	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1931		ret = -EINVAL;
1932		goto out_drop_write;
1933	}
1934
1935	if (copy_from_user(&flags, arg, sizeof(flags))) {
1936		ret = -EFAULT;
1937		goto out_drop_write;
1938	}
1939
 
 
 
 
 
1940	if (flags & ~BTRFS_SUBVOL_RDONLY) {
1941		ret = -EOPNOTSUPP;
1942		goto out_drop_write;
1943	}
1944
1945	down_write(&fs_info->subvol_sem);
1946
1947	/* nothing to do */
1948	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1949		goto out_drop_sem;
1950
1951	root_flags = btrfs_root_flags(&root->root_item);
1952	if (flags & BTRFS_SUBVOL_RDONLY) {
1953		btrfs_set_root_flags(&root->root_item,
1954				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1955	} else {
1956		/*
1957		 * Block RO -> RW transition if this subvolume is involved in
1958		 * send
1959		 */
1960		spin_lock(&root->root_item_lock);
1961		if (root->send_in_progress == 0) {
1962			btrfs_set_root_flags(&root->root_item,
1963				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1964			spin_unlock(&root->root_item_lock);
1965		} else {
1966			spin_unlock(&root->root_item_lock);
1967			btrfs_warn(fs_info,
1968				   "Attempt to set subvolume %llu read-write during send",
1969				   root->root_key.objectid);
1970			ret = -EPERM;
1971			goto out_drop_sem;
1972		}
1973	}
1974
1975	trans = btrfs_start_transaction(root, 1);
1976	if (IS_ERR(trans)) {
1977		ret = PTR_ERR(trans);
1978		goto out_reset;
1979	}
1980
1981	ret = btrfs_update_root(trans, fs_info->tree_root,
1982				&root->root_key, &root->root_item);
1983	if (ret < 0) {
1984		btrfs_end_transaction(trans);
1985		goto out_reset;
1986	}
1987
1988	ret = btrfs_commit_transaction(trans);
1989
 
1990out_reset:
1991	if (ret)
1992		btrfs_set_root_flags(&root->root_item, root_flags);
1993out_drop_sem:
1994	up_write(&fs_info->subvol_sem);
1995out_drop_write:
1996	mnt_drop_write_file(file);
1997out:
1998	return ret;
1999}
2000
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2001static noinline int key_in_sk(struct btrfs_key *key,
2002			      struct btrfs_ioctl_search_key *sk)
2003{
2004	struct btrfs_key test;
2005	int ret;
2006
2007	test.objectid = sk->min_objectid;
2008	test.type = sk->min_type;
2009	test.offset = sk->min_offset;
2010
2011	ret = btrfs_comp_cpu_keys(key, &test);
2012	if (ret < 0)
2013		return 0;
2014
2015	test.objectid = sk->max_objectid;
2016	test.type = sk->max_type;
2017	test.offset = sk->max_offset;
2018
2019	ret = btrfs_comp_cpu_keys(key, &test);
2020	if (ret > 0)
2021		return 0;
2022	return 1;
2023}
2024
2025static noinline int copy_to_sk(struct btrfs_path *path,
2026			       struct btrfs_key *key,
2027			       struct btrfs_ioctl_search_key *sk,
2028			       size_t *buf_size,
2029			       char __user *ubuf,
2030			       unsigned long *sk_offset,
2031			       int *num_found)
2032{
2033	u64 found_transid;
2034	struct extent_buffer *leaf;
2035	struct btrfs_ioctl_search_header sh;
2036	struct btrfs_key test;
2037	unsigned long item_off;
2038	unsigned long item_len;
2039	int nritems;
2040	int i;
2041	int slot;
2042	int ret = 0;
2043
2044	leaf = path->nodes[0];
2045	slot = path->slots[0];
2046	nritems = btrfs_header_nritems(leaf);
2047
2048	if (btrfs_header_generation(leaf) > sk->max_transid) {
2049		i = nritems;
2050		goto advance_key;
2051	}
2052	found_transid = btrfs_header_generation(leaf);
2053
2054	for (i = slot; i < nritems; i++) {
2055		item_off = btrfs_item_ptr_offset(leaf, i);
2056		item_len = btrfs_item_size_nr(leaf, i);
2057
2058		btrfs_item_key_to_cpu(leaf, key, i);
2059		if (!key_in_sk(key, sk))
2060			continue;
2061
2062		if (sizeof(sh) + item_len > *buf_size) {
2063			if (*num_found) {
2064				ret = 1;
2065				goto out;
2066			}
2067
2068			/*
2069			 * return one empty item back for v1, which does not
2070			 * handle -EOVERFLOW
2071			 */
2072
2073			*buf_size = sizeof(sh) + item_len;
2074			item_len = 0;
2075			ret = -EOVERFLOW;
2076		}
2077
2078		if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
2079			ret = 1;
2080			goto out;
2081		}
2082
2083		sh.objectid = key->objectid;
2084		sh.offset = key->offset;
2085		sh.type = key->type;
2086		sh.len = item_len;
2087		sh.transid = found_transid;
2088
2089		/*
2090		 * Copy search result header. If we fault then loop again so we
2091		 * can fault in the pages and -EFAULT there if there's a
2092		 * problem. Otherwise we'll fault and then copy the buffer in
2093		 * properly this next time through
2094		 */
2095		if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
2096			ret = 0;
2097			goto out;
2098		}
2099
2100		*sk_offset += sizeof(sh);
2101
2102		if (item_len) {
2103			char __user *up = ubuf + *sk_offset;
2104			/*
2105			 * Copy the item, same behavior as above, but reset the
2106			 * * sk_offset so we copy the full thing again.
2107			 */
2108			if (read_extent_buffer_to_user_nofault(leaf, up,
2109						item_off, item_len)) {
2110				ret = 0;
2111				*sk_offset -= sizeof(sh);
2112				goto out;
2113			}
2114
2115			*sk_offset += item_len;
2116		}
2117		(*num_found)++;
2118
2119		if (ret) /* -EOVERFLOW from above */
2120			goto out;
2121
2122		if (*num_found >= sk->nr_items) {
2123			ret = 1;
2124			goto out;
2125		}
2126	}
2127advance_key:
2128	ret = 0;
2129	test.objectid = sk->max_objectid;
2130	test.type = sk->max_type;
2131	test.offset = sk->max_offset;
2132	if (btrfs_comp_cpu_keys(key, &test) >= 0)
2133		ret = 1;
2134	else if (key->offset < (u64)-1)
2135		key->offset++;
2136	else if (key->type < (u8)-1) {
2137		key->offset = 0;
2138		key->type++;
2139	} else if (key->objectid < (u64)-1) {
2140		key->offset = 0;
2141		key->type = 0;
2142		key->objectid++;
2143	} else
2144		ret = 1;
2145out:
2146	/*
2147	 *  0: all items from this leaf copied, continue with next
2148	 *  1: * more items can be copied, but unused buffer is too small
2149	 *     * all items were found
2150	 *     Either way, it will stops the loop which iterates to the next
2151	 *     leaf
2152	 *  -EOVERFLOW: item was to large for buffer
2153	 *  -EFAULT: could not copy extent buffer back to userspace
2154	 */
2155	return ret;
2156}
2157
2158static noinline int search_ioctl(struct inode *inode,
2159				 struct btrfs_ioctl_search_key *sk,
2160				 size_t *buf_size,
2161				 char __user *ubuf)
2162{
2163	struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
2164	struct btrfs_root *root;
2165	struct btrfs_key key;
2166	struct btrfs_path *path;
2167	int ret;
2168	int num_found = 0;
2169	unsigned long sk_offset = 0;
2170
2171	if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
2172		*buf_size = sizeof(struct btrfs_ioctl_search_header);
2173		return -EOVERFLOW;
2174	}
2175
2176	path = btrfs_alloc_path();
2177	if (!path)
2178		return -ENOMEM;
2179
2180	if (sk->tree_id == 0) {
2181		/* search the root of the inode that was passed */
2182		root = btrfs_grab_root(BTRFS_I(inode)->root);
2183	} else {
2184		root = btrfs_get_fs_root(info, sk->tree_id, true);
 
 
 
2185		if (IS_ERR(root)) {
2186			btrfs_free_path(path);
2187			return PTR_ERR(root);
2188		}
2189	}
2190
2191	key.objectid = sk->min_objectid;
2192	key.type = sk->min_type;
2193	key.offset = sk->min_offset;
2194
2195	while (1) {
2196		ret = fault_in_pages_writeable(ubuf + sk_offset,
2197					       *buf_size - sk_offset);
2198		if (ret)
2199			break;
2200
2201		ret = btrfs_search_forward(root, &key, path, sk->min_transid);
2202		if (ret != 0) {
2203			if (ret > 0)
2204				ret = 0;
2205			goto err;
2206		}
2207		ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
2208				 &sk_offset, &num_found);
2209		btrfs_release_path(path);
2210		if (ret)
2211			break;
2212
2213	}
2214	if (ret > 0)
2215		ret = 0;
2216err:
2217	sk->nr_items = num_found;
2218	btrfs_put_root(root);
2219	btrfs_free_path(path);
2220	return ret;
2221}
2222
2223static noinline int btrfs_ioctl_tree_search(struct file *file,
2224					   void __user *argp)
2225{
2226	struct btrfs_ioctl_search_args __user *uargs;
2227	struct btrfs_ioctl_search_key sk;
2228	struct inode *inode;
2229	int ret;
2230	size_t buf_size;
2231
2232	if (!capable(CAP_SYS_ADMIN))
2233		return -EPERM;
2234
2235	uargs = (struct btrfs_ioctl_search_args __user *)argp;
2236
2237	if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
2238		return -EFAULT;
2239
2240	buf_size = sizeof(uargs->buf);
2241
2242	inode = file_inode(file);
2243	ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
2244
2245	/*
2246	 * In the origin implementation an overflow is handled by returning a
2247	 * search header with a len of zero, so reset ret.
2248	 */
2249	if (ret == -EOVERFLOW)
2250		ret = 0;
2251
2252	if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
2253		ret = -EFAULT;
2254	return ret;
2255}
2256
2257static noinline int btrfs_ioctl_tree_search_v2(struct file *file,
2258					       void __user *argp)
2259{
2260	struct btrfs_ioctl_search_args_v2 __user *uarg;
2261	struct btrfs_ioctl_search_args_v2 args;
2262	struct inode *inode;
2263	int ret;
2264	size_t buf_size;
2265	const size_t buf_limit = SZ_16M;
2266
2267	if (!capable(CAP_SYS_ADMIN))
2268		return -EPERM;
2269
2270	/* copy search header and buffer size */
2271	uarg = (struct btrfs_ioctl_search_args_v2 __user *)argp;
2272	if (copy_from_user(&args, uarg, sizeof(args)))
2273		return -EFAULT;
2274
2275	buf_size = args.buf_size;
2276
 
 
 
2277	/* limit result size to 16MB */
2278	if (buf_size > buf_limit)
2279		buf_size = buf_limit;
2280
2281	inode = file_inode(file);
2282	ret = search_ioctl(inode, &args.key, &buf_size,
2283			   (char __user *)(&uarg->buf[0]));
2284	if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
2285		ret = -EFAULT;
2286	else if (ret == -EOVERFLOW &&
2287		copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
2288		ret = -EFAULT;
2289
2290	return ret;
2291}
2292
2293/*
2294 * Search INODE_REFs to identify path name of 'dirid' directory
2295 * in a 'tree_id' tree. and sets path name to 'name'.
2296 */
2297static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
2298				u64 tree_id, u64 dirid, char *name)
2299{
2300	struct btrfs_root *root;
2301	struct btrfs_key key;
2302	char *ptr;
2303	int ret = -1;
2304	int slot;
2305	int len;
2306	int total_len = 0;
2307	struct btrfs_inode_ref *iref;
2308	struct extent_buffer *l;
2309	struct btrfs_path *path;
2310
2311	if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
2312		name[0]='\0';
2313		return 0;
2314	}
2315
2316	path = btrfs_alloc_path();
2317	if (!path)
2318		return -ENOMEM;
2319
2320	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
2321
2322	root = btrfs_get_fs_root(info, tree_id, true);
 
 
 
2323	if (IS_ERR(root)) {
2324		ret = PTR_ERR(root);
2325		root = NULL;
2326		goto out;
2327	}
2328
2329	key.objectid = dirid;
2330	key.type = BTRFS_INODE_REF_KEY;
2331	key.offset = (u64)-1;
2332
2333	while (1) {
2334		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2335		if (ret < 0)
2336			goto out;
2337		else if (ret > 0) {
2338			ret = btrfs_previous_item(root, path, dirid,
2339						  BTRFS_INODE_REF_KEY);
2340			if (ret < 0)
2341				goto out;
2342			else if (ret > 0) {
2343				ret = -ENOENT;
2344				goto out;
2345			}
2346		}
2347
2348		l = path->nodes[0];
2349		slot = path->slots[0];
2350		btrfs_item_key_to_cpu(l, &key, slot);
2351
2352		iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
2353		len = btrfs_inode_ref_name_len(l, iref);
2354		ptr -= len + 1;
2355		total_len += len + 1;
2356		if (ptr < name) {
2357			ret = -ENAMETOOLONG;
2358			goto out;
2359		}
2360
2361		*(ptr + len) = '/';
2362		read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
2363
2364		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
2365			break;
2366
2367		btrfs_release_path(path);
2368		key.objectid = key.offset;
2369		key.offset = (u64)-1;
2370		dirid = key.objectid;
2371	}
2372	memmove(name, ptr, total_len);
2373	name[total_len] = '\0';
2374	ret = 0;
2375out:
2376	btrfs_put_root(root);
2377	btrfs_free_path(path);
2378	return ret;
2379}
2380
2381static int btrfs_search_path_in_tree_user(struct inode *inode,
2382				struct btrfs_ioctl_ino_lookup_user_args *args)
2383{
2384	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
2385	struct super_block *sb = inode->i_sb;
2386	struct btrfs_key upper_limit = BTRFS_I(inode)->location;
2387	u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
2388	u64 dirid = args->dirid;
2389	unsigned long item_off;
2390	unsigned long item_len;
2391	struct btrfs_inode_ref *iref;
2392	struct btrfs_root_ref *rref;
2393	struct btrfs_root *root = NULL;
2394	struct btrfs_path *path;
2395	struct btrfs_key key, key2;
2396	struct extent_buffer *leaf;
2397	struct inode *temp_inode;
2398	char *ptr;
2399	int slot;
2400	int len;
2401	int total_len = 0;
2402	int ret;
2403
2404	path = btrfs_alloc_path();
2405	if (!path)
2406		return -ENOMEM;
2407
2408	/*
2409	 * If the bottom subvolume does not exist directly under upper_limit,
2410	 * construct the path in from the bottom up.
2411	 */
2412	if (dirid != upper_limit.objectid) {
2413		ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
2414
2415		root = btrfs_get_fs_root(fs_info, treeid, true);
2416		if (IS_ERR(root)) {
2417			ret = PTR_ERR(root);
2418			goto out;
2419		}
2420
2421		key.objectid = dirid;
2422		key.type = BTRFS_INODE_REF_KEY;
2423		key.offset = (u64)-1;
2424		while (1) {
2425			ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2426			if (ret < 0) {
2427				goto out_put;
2428			} else if (ret > 0) {
2429				ret = btrfs_previous_item(root, path, dirid,
2430							  BTRFS_INODE_REF_KEY);
2431				if (ret < 0) {
2432					goto out_put;
2433				} else if (ret > 0) {
2434					ret = -ENOENT;
2435					goto out_put;
2436				}
2437			}
2438
2439			leaf = path->nodes[0];
2440			slot = path->slots[0];
2441			btrfs_item_key_to_cpu(leaf, &key, slot);
2442
2443			iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
2444			len = btrfs_inode_ref_name_len(leaf, iref);
2445			ptr -= len + 1;
2446			total_len += len + 1;
2447			if (ptr < args->path) {
2448				ret = -ENAMETOOLONG;
2449				goto out_put;
2450			}
2451
2452			*(ptr + len) = '/';
2453			read_extent_buffer(leaf, ptr,
2454					(unsigned long)(iref + 1), len);
2455
2456			/* Check the read+exec permission of this directory */
2457			ret = btrfs_previous_item(root, path, dirid,
2458						  BTRFS_INODE_ITEM_KEY);
2459			if (ret < 0) {
2460				goto out_put;
2461			} else if (ret > 0) {
2462				ret = -ENOENT;
2463				goto out_put;
2464			}
2465
2466			leaf = path->nodes[0];
2467			slot = path->slots[0];
2468			btrfs_item_key_to_cpu(leaf, &key2, slot);
2469			if (key2.objectid != dirid) {
2470				ret = -ENOENT;
2471				goto out_put;
2472			}
2473
2474			temp_inode = btrfs_iget(sb, key2.objectid, root);
2475			if (IS_ERR(temp_inode)) {
2476				ret = PTR_ERR(temp_inode);
2477				goto out_put;
2478			}
2479			ret = inode_permission(temp_inode, MAY_READ | MAY_EXEC);
2480			iput(temp_inode);
2481			if (ret) {
2482				ret = -EACCES;
2483				goto out_put;
2484			}
2485
2486			if (key.offset == upper_limit.objectid)
2487				break;
2488			if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
2489				ret = -EACCES;
2490				goto out_put;
2491			}
2492
2493			btrfs_release_path(path);
2494			key.objectid = key.offset;
2495			key.offset = (u64)-1;
2496			dirid = key.objectid;
2497		}
2498
2499		memmove(args->path, ptr, total_len);
2500		args->path[total_len] = '\0';
2501		btrfs_put_root(root);
2502		root = NULL;
2503		btrfs_release_path(path);
2504	}
2505
2506	/* Get the bottom subvolume's name from ROOT_REF */
2507	key.objectid = treeid;
2508	key.type = BTRFS_ROOT_REF_KEY;
2509	key.offset = args->treeid;
2510	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2511	if (ret < 0) {
2512		goto out;
2513	} else if (ret > 0) {
2514		ret = -ENOENT;
2515		goto out;
2516	}
2517
2518	leaf = path->nodes[0];
2519	slot = path->slots[0];
2520	btrfs_item_key_to_cpu(leaf, &key, slot);
2521
2522	item_off = btrfs_item_ptr_offset(leaf, slot);
2523	item_len = btrfs_item_size_nr(leaf, slot);
2524	/* Check if dirid in ROOT_REF corresponds to passed dirid */
2525	rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2526	if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2527		ret = -EINVAL;
2528		goto out;
2529	}
2530
2531	/* Copy subvolume's name */
2532	item_off += sizeof(struct btrfs_root_ref);
2533	item_len -= sizeof(struct btrfs_root_ref);
2534	read_extent_buffer(leaf, args->name, item_off, item_len);
2535	args->name[item_len] = 0;
2536
2537out_put:
2538	btrfs_put_root(root);
2539out:
2540	btrfs_free_path(path);
2541	return ret;
2542}
2543
2544static noinline int btrfs_ioctl_ino_lookup(struct file *file,
2545					   void __user *argp)
2546{
2547	struct btrfs_ioctl_ino_lookup_args *args;
2548	struct inode *inode;
2549	int ret = 0;
2550
2551	args = memdup_user(argp, sizeof(*args));
2552	if (IS_ERR(args))
2553		return PTR_ERR(args);
2554
2555	inode = file_inode(file);
2556
2557	/*
2558	 * Unprivileged query to obtain the containing subvolume root id. The
2559	 * path is reset so it's consistent with btrfs_search_path_in_tree.
2560	 */
2561	if (args->treeid == 0)
2562		args->treeid = BTRFS_I(inode)->root->root_key.objectid;
2563
2564	if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2565		args->name[0] = 0;
2566		goto out;
2567	}
2568
2569	if (!capable(CAP_SYS_ADMIN)) {
2570		ret = -EPERM;
2571		goto out;
2572	}
2573
2574	ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
2575					args->treeid, args->objectid,
2576					args->name);
2577
2578out:
2579	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2580		ret = -EFAULT;
2581
2582	kfree(args);
2583	return ret;
2584}
2585
2586/*
2587 * Version of ino_lookup ioctl (unprivileged)
2588 *
2589 * The main differences from ino_lookup ioctl are:
2590 *
2591 *   1. Read + Exec permission will be checked using inode_permission() during
2592 *      path construction. -EACCES will be returned in case of failure.
2593 *   2. Path construction will be stopped at the inode number which corresponds
2594 *      to the fd with which this ioctl is called. If constructed path does not
2595 *      exist under fd's inode, -EACCES will be returned.
2596 *   3. The name of bottom subvolume is also searched and filled.
2597 */
2598static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2599{
2600	struct btrfs_ioctl_ino_lookup_user_args *args;
2601	struct inode *inode;
2602	int ret;
2603
2604	args = memdup_user(argp, sizeof(*args));
2605	if (IS_ERR(args))
2606		return PTR_ERR(args);
2607
2608	inode = file_inode(file);
2609
2610	if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2611	    BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2612		/*
2613		 * The subvolume does not exist under fd with which this is
2614		 * called
2615		 */
2616		kfree(args);
2617		return -EACCES;
2618	}
2619
2620	ret = btrfs_search_path_in_tree_user(inode, args);
2621
2622	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2623		ret = -EFAULT;
2624
2625	kfree(args);
2626	return ret;
2627}
2628
2629/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2630static int btrfs_ioctl_get_subvol_info(struct file *file, void __user *argp)
2631{
2632	struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2633	struct btrfs_fs_info *fs_info;
2634	struct btrfs_root *root;
2635	struct btrfs_path *path;
2636	struct btrfs_key key;
2637	struct btrfs_root_item *root_item;
2638	struct btrfs_root_ref *rref;
2639	struct extent_buffer *leaf;
2640	unsigned long item_off;
2641	unsigned long item_len;
2642	struct inode *inode;
2643	int slot;
2644	int ret = 0;
2645
2646	path = btrfs_alloc_path();
2647	if (!path)
2648		return -ENOMEM;
2649
2650	subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2651	if (!subvol_info) {
2652		btrfs_free_path(path);
2653		return -ENOMEM;
2654	}
2655
2656	inode = file_inode(file);
2657	fs_info = BTRFS_I(inode)->root->fs_info;
2658
2659	/* Get root_item of inode's subvolume */
2660	key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2661	root = btrfs_get_fs_root(fs_info, key.objectid, true);
2662	if (IS_ERR(root)) {
2663		ret = PTR_ERR(root);
2664		goto out_free;
2665	}
2666	root_item = &root->root_item;
2667
2668	subvol_info->treeid = key.objectid;
2669
2670	subvol_info->generation = btrfs_root_generation(root_item);
2671	subvol_info->flags = btrfs_root_flags(root_item);
2672
2673	memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2674	memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2675						    BTRFS_UUID_SIZE);
2676	memcpy(subvol_info->received_uuid, root_item->received_uuid,
2677						    BTRFS_UUID_SIZE);
2678
2679	subvol_info->ctransid = btrfs_root_ctransid(root_item);
2680	subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2681	subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2682
2683	subvol_info->otransid = btrfs_root_otransid(root_item);
2684	subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2685	subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2686
2687	subvol_info->stransid = btrfs_root_stransid(root_item);
2688	subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2689	subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2690
2691	subvol_info->rtransid = btrfs_root_rtransid(root_item);
2692	subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2693	subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2694
2695	if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2696		/* Search root tree for ROOT_BACKREF of this subvolume */
2697		key.type = BTRFS_ROOT_BACKREF_KEY;
2698		key.offset = 0;
2699		ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2700		if (ret < 0) {
2701			goto out;
2702		} else if (path->slots[0] >=
2703			   btrfs_header_nritems(path->nodes[0])) {
2704			ret = btrfs_next_leaf(fs_info->tree_root, path);
2705			if (ret < 0) {
2706				goto out;
2707			} else if (ret > 0) {
2708				ret = -EUCLEAN;
2709				goto out;
2710			}
2711		}
2712
2713		leaf = path->nodes[0];
2714		slot = path->slots[0];
2715		btrfs_item_key_to_cpu(leaf, &key, slot);
2716		if (key.objectid == subvol_info->treeid &&
2717		    key.type == BTRFS_ROOT_BACKREF_KEY) {
2718			subvol_info->parent_id = key.offset;
2719
2720			rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2721			subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2722
2723			item_off = btrfs_item_ptr_offset(leaf, slot)
2724					+ sizeof(struct btrfs_root_ref);
2725			item_len = btrfs_item_size_nr(leaf, slot)
2726					- sizeof(struct btrfs_root_ref);
2727			read_extent_buffer(leaf, subvol_info->name,
2728					   item_off, item_len);
2729		} else {
2730			ret = -ENOENT;
2731			goto out;
2732		}
2733	}
2734
2735	if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2736		ret = -EFAULT;
2737
2738out:
2739	btrfs_put_root(root);
2740out_free:
2741	btrfs_free_path(path);
2742	kfree(subvol_info);
2743	return ret;
2744}
2745
2746/*
2747 * Return ROOT_REF information of the subvolume containing this inode
2748 * except the subvolume name.
2749 */
2750static int btrfs_ioctl_get_subvol_rootref(struct file *file, void __user *argp)
2751{
2752	struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2753	struct btrfs_root_ref *rref;
2754	struct btrfs_root *root;
2755	struct btrfs_path *path;
2756	struct btrfs_key key;
2757	struct extent_buffer *leaf;
2758	struct inode *inode;
2759	u64 objectid;
2760	int slot;
2761	int ret;
2762	u8 found;
2763
2764	path = btrfs_alloc_path();
2765	if (!path)
2766		return -ENOMEM;
2767
2768	rootrefs = memdup_user(argp, sizeof(*rootrefs));
2769	if (IS_ERR(rootrefs)) {
2770		btrfs_free_path(path);
2771		return PTR_ERR(rootrefs);
2772	}
2773
2774	inode = file_inode(file);
2775	root = BTRFS_I(inode)->root->fs_info->tree_root;
2776	objectid = BTRFS_I(inode)->root->root_key.objectid;
2777
2778	key.objectid = objectid;
2779	key.type = BTRFS_ROOT_REF_KEY;
2780	key.offset = rootrefs->min_treeid;
2781	found = 0;
2782
2783	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2784	if (ret < 0) {
2785		goto out;
2786	} else if (path->slots[0] >=
2787		   btrfs_header_nritems(path->nodes[0])) {
2788		ret = btrfs_next_leaf(root, path);
2789		if (ret < 0) {
2790			goto out;
2791		} else if (ret > 0) {
2792			ret = -EUCLEAN;
2793			goto out;
2794		}
2795	}
2796	while (1) {
2797		leaf = path->nodes[0];
2798		slot = path->slots[0];
2799
2800		btrfs_item_key_to_cpu(leaf, &key, slot);
2801		if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2802			ret = 0;
2803			goto out;
2804		}
2805
2806		if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2807			ret = -EOVERFLOW;
2808			goto out;
2809		}
2810
2811		rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2812		rootrefs->rootref[found].treeid = key.offset;
2813		rootrefs->rootref[found].dirid =
2814				  btrfs_root_ref_dirid(leaf, rref);
2815		found++;
2816
2817		ret = btrfs_next_item(root, path);
2818		if (ret < 0) {
2819			goto out;
2820		} else if (ret > 0) {
2821			ret = -EUCLEAN;
2822			goto out;
2823		}
2824	}
2825
2826out:
2827	if (!ret || ret == -EOVERFLOW) {
2828		rootrefs->num_items = found;
2829		/* update min_treeid for next search */
2830		if (found)
2831			rootrefs->min_treeid =
2832				rootrefs->rootref[found - 1].treeid + 1;
2833		if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2834			ret = -EFAULT;
2835	}
2836
2837	kfree(rootrefs);
2838	btrfs_free_path(path);
2839
2840	return ret;
2841}
2842
2843static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2844					     void __user *arg,
2845					     bool destroy_v2)
2846{
2847	struct dentry *parent = file->f_path.dentry;
2848	struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2849	struct dentry *dentry;
2850	struct inode *dir = d_inode(parent);
2851	struct inode *inode;
2852	struct btrfs_root *root = BTRFS_I(dir)->root;
2853	struct btrfs_root *dest = NULL;
2854	struct btrfs_ioctl_vol_args *vol_args = NULL;
2855	struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
2856	char *subvol_name, *subvol_name_ptr = NULL;
2857	int subvol_namelen;
 
 
 
2858	int err = 0;
2859	bool destroy_parent = false;
2860
2861	if (destroy_v2) {
2862		vol_args2 = memdup_user(arg, sizeof(*vol_args2));
2863		if (IS_ERR(vol_args2))
2864			return PTR_ERR(vol_args2);
2865
2866		if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
2867			err = -EOPNOTSUPP;
2868			goto out;
2869		}
2870
2871		/*
2872		 * If SPEC_BY_ID is not set, we are looking for the subvolume by
2873		 * name, same as v1 currently does.
2874		 */
2875		if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
2876			vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
2877			subvol_name = vol_args2->name;
2878
2879			err = mnt_want_write_file(file);
2880			if (err)
2881				goto out;
2882		} else {
2883			if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
2884				err = -EINVAL;
2885				goto out;
2886			}
2887
2888			err = mnt_want_write_file(file);
2889			if (err)
2890				goto out;
2891
2892			dentry = btrfs_get_dentry(fs_info->sb,
2893					BTRFS_FIRST_FREE_OBJECTID,
2894					vol_args2->subvolid, 0, 0);
2895			if (IS_ERR(dentry)) {
2896				err = PTR_ERR(dentry);
2897				goto out_drop_write;
2898			}
2899
2900			/*
2901			 * Change the default parent since the subvolume being
2902			 * deleted can be outside of the current mount point.
2903			 */
2904			parent = btrfs_get_parent(dentry);
2905
2906			/*
2907			 * At this point dentry->d_name can point to '/' if the
2908			 * subvolume we want to destroy is outsite of the
2909			 * current mount point, so we need to release the
2910			 * current dentry and execute the lookup to return a new
2911			 * one with ->d_name pointing to the
2912			 * <mount point>/subvol_name.
2913			 */
2914			dput(dentry);
2915			if (IS_ERR(parent)) {
2916				err = PTR_ERR(parent);
2917				goto out_drop_write;
2918			}
2919			dir = d_inode(parent);
2920
2921			/*
2922			 * If v2 was used with SPEC_BY_ID, a new parent was
2923			 * allocated since the subvolume can be outside of the
2924			 * current mount point. Later on we need to release this
2925			 * new parent dentry.
2926			 */
2927			destroy_parent = true;
2928
2929			subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
2930						fs_info, vol_args2->subvolid);
2931			if (IS_ERR(subvol_name_ptr)) {
2932				err = PTR_ERR(subvol_name_ptr);
2933				goto free_parent;
2934			}
2935			/* subvol_name_ptr is already NULL termined */
2936			subvol_name = (char *)kbasename(subvol_name_ptr);
2937		}
2938	} else {
2939		vol_args = memdup_user(arg, sizeof(*vol_args));
2940		if (IS_ERR(vol_args))
2941			return PTR_ERR(vol_args);
2942
2943		vol_args->name[BTRFS_PATH_NAME_MAX] = 0;
2944		subvol_name = vol_args->name;
2945
2946		err = mnt_want_write_file(file);
2947		if (err)
2948			goto out;
2949	}
2950
2951	subvol_namelen = strlen(subvol_name);
 
 
2952
2953	if (strchr(subvol_name, '/') ||
2954	    strncmp(subvol_name, "..", subvol_namelen) == 0) {
 
 
2955		err = -EINVAL;
2956		goto free_subvol_name;
2957	}
2958
2959	if (!S_ISDIR(dir->i_mode)) {
2960		err = -ENOTDIR;
2961		goto free_subvol_name;
2962	}
2963
2964	err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2965	if (err == -EINTR)
2966		goto free_subvol_name;
2967	dentry = lookup_one_len(subvol_name, parent, subvol_namelen);
2968	if (IS_ERR(dentry)) {
2969		err = PTR_ERR(dentry);
2970		goto out_unlock_dir;
2971	}
2972
2973	if (d_really_is_negative(dentry)) {
2974		err = -ENOENT;
2975		goto out_dput;
2976	}
2977
2978	inode = d_inode(dentry);
2979	dest = BTRFS_I(inode)->root;
2980	if (!capable(CAP_SYS_ADMIN)) {
2981		/*
2982		 * Regular user.  Only allow this with a special mount
2983		 * option, when the user has write+exec access to the
2984		 * subvol root, and when rmdir(2) would have been
2985		 * allowed.
2986		 *
2987		 * Note that this is _not_ check that the subvol is
2988		 * empty or doesn't contain data that we wouldn't
2989		 * otherwise be able to delete.
2990		 *
2991		 * Users who want to delete empty subvols should try
2992		 * rmdir(2).
2993		 */
2994		err = -EPERM;
2995		if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2996			goto out_dput;
2997
2998		/*
2999		 * Do not allow deletion if the parent dir is the same
3000		 * as the dir to be deleted.  That means the ioctl
3001		 * must be called on the dentry referencing the root
3002		 * of the subvol, not a random directory contained
3003		 * within it.
3004		 */
3005		err = -EINVAL;
3006		if (root == dest)
3007			goto out_dput;
3008
3009		err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
3010		if (err)
3011			goto out_dput;
3012	}
3013
3014	/* check if subvolume may be deleted by a user */
3015	err = btrfs_may_delete(dir, dentry, 1);
3016	if (err)
3017		goto out_dput;
3018
3019	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
3020		err = -EINVAL;
3021		goto out_dput;
3022	}
3023
3024	inode_lock(inode);
3025	err = btrfs_delete_subvolume(dir, dentry);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3026	inode_unlock(inode);
3027	if (!err) {
3028		fsnotify_rmdir(dir, dentry);
 
3029		d_delete(dentry);
3030	}
3031
 
 
 
 
 
 
3032out_dput:
3033	dput(dentry);
3034out_unlock_dir:
3035	inode_unlock(dir);
3036free_subvol_name:
3037	kfree(subvol_name_ptr);
3038free_parent:
3039	if (destroy_parent)
3040		dput(parent);
3041out_drop_write:
3042	mnt_drop_write_file(file);
3043out:
3044	kfree(vol_args2);
3045	kfree(vol_args);
3046	return err;
3047}
3048
3049static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
3050{
3051	struct inode *inode = file_inode(file);
3052	struct btrfs_root *root = BTRFS_I(inode)->root;
3053	struct btrfs_ioctl_defrag_range_args *range;
3054	int ret;
3055
3056	ret = mnt_want_write_file(file);
3057	if (ret)
3058		return ret;
3059
3060	if (btrfs_root_readonly(root)) {
3061		ret = -EROFS;
3062		goto out;
3063	}
3064
3065	switch (inode->i_mode & S_IFMT) {
3066	case S_IFDIR:
3067		if (!capable(CAP_SYS_ADMIN)) {
3068			ret = -EPERM;
3069			goto out;
3070		}
3071		ret = btrfs_defrag_root(root);
 
 
 
3072		break;
3073	case S_IFREG:
3074		/*
3075		 * Note that this does not check the file descriptor for write
3076		 * access. This prevents defragmenting executables that are
3077		 * running and allows defrag on files open in read-only mode.
3078		 */
3079		if (!capable(CAP_SYS_ADMIN) &&
3080		    inode_permission(inode, MAY_WRITE)) {
3081			ret = -EPERM;
3082			goto out;
3083		}
3084
3085		range = kzalloc(sizeof(*range), GFP_KERNEL);
3086		if (!range) {
3087			ret = -ENOMEM;
3088			goto out;
3089		}
3090
3091		if (argp) {
3092			if (copy_from_user(range, argp,
3093					   sizeof(*range))) {
3094				ret = -EFAULT;
3095				kfree(range);
3096				goto out;
3097			}
3098			/* compression requires us to start the IO */
3099			if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
3100				range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
3101				range->extent_thresh = (u32)-1;
3102			}
3103		} else {
3104			/* the rest are all set to zero by kzalloc */
3105			range->len = (u64)-1;
3106		}
3107		ret = btrfs_defrag_file(file_inode(file), file,
3108					range, BTRFS_OLDEST_GENERATION, 0);
3109		if (ret > 0)
3110			ret = 0;
3111		kfree(range);
3112		break;
3113	default:
3114		ret = -EINVAL;
3115	}
3116out:
3117	mnt_drop_write_file(file);
3118	return ret;
3119}
3120
3121static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
3122{
3123	struct btrfs_ioctl_vol_args *vol_args;
3124	int ret;
3125
3126	if (!capable(CAP_SYS_ADMIN))
3127		return -EPERM;
3128
3129	if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags))
3130		return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3131
 
3132	vol_args = memdup_user(arg, sizeof(*vol_args));
3133	if (IS_ERR(vol_args)) {
3134		ret = PTR_ERR(vol_args);
3135		goto out;
3136	}
3137
3138	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
3139	ret = btrfs_init_new_device(fs_info, vol_args->name);
3140
3141	if (!ret)
3142		btrfs_info(fs_info, "disk added %s", vol_args->name);
3143
3144	kfree(vol_args);
3145out:
3146	clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
 
3147	return ret;
3148}
3149
3150static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
3151{
3152	struct inode *inode = file_inode(file);
3153	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3154	struct btrfs_ioctl_vol_args_v2 *vol_args;
3155	int ret;
3156
3157	if (!capable(CAP_SYS_ADMIN))
3158		return -EPERM;
3159
3160	ret = mnt_want_write_file(file);
3161	if (ret)
3162		return ret;
3163
3164	vol_args = memdup_user(arg, sizeof(*vol_args));
3165	if (IS_ERR(vol_args)) {
3166		ret = PTR_ERR(vol_args);
3167		goto err_drop;
3168	}
3169
3170	if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
3171		ret = -EOPNOTSUPP;
3172		goto out;
3173	}
3174
3175	if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3176		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3177		goto out;
3178	}
3179
 
3180	if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
3181		ret = btrfs_rm_device(fs_info, NULL, vol_args->devid);
3182	} else {
3183		vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
3184		ret = btrfs_rm_device(fs_info, vol_args->name, 0);
3185	}
3186	clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
 
3187
3188	if (!ret) {
3189		if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
3190			btrfs_info(fs_info, "device deleted: id %llu",
3191					vol_args->devid);
3192		else
3193			btrfs_info(fs_info, "device deleted: %s",
3194					vol_args->name);
3195	}
3196out:
3197	kfree(vol_args);
3198err_drop:
3199	mnt_drop_write_file(file);
3200	return ret;
3201}
3202
3203static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
3204{
3205	struct inode *inode = file_inode(file);
3206	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3207	struct btrfs_ioctl_vol_args *vol_args;
3208	int ret;
3209
3210	if (!capable(CAP_SYS_ADMIN))
3211		return -EPERM;
3212
3213	ret = mnt_want_write_file(file);
3214	if (ret)
3215		return ret;
3216
3217	if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
3218		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3219		goto out_drop_write;
3220	}
3221
3222	vol_args = memdup_user(arg, sizeof(*vol_args));
3223	if (IS_ERR(vol_args)) {
3224		ret = PTR_ERR(vol_args);
3225		goto out;
3226	}
3227
3228	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
 
3229	ret = btrfs_rm_device(fs_info, vol_args->name, 0);
 
3230
3231	if (!ret)
3232		btrfs_info(fs_info, "disk deleted %s", vol_args->name);
3233	kfree(vol_args);
3234out:
3235	clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
3236out_drop_write:
3237	mnt_drop_write_file(file);
3238
3239	return ret;
3240}
3241
3242static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
3243				void __user *arg)
3244{
3245	struct btrfs_ioctl_fs_info_args *fi_args;
3246	struct btrfs_device *device;
3247	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
3248	u64 flags_in;
3249	int ret = 0;
3250
3251	fi_args = memdup_user(arg, sizeof(*fi_args));
3252	if (IS_ERR(fi_args))
3253		return PTR_ERR(fi_args);
3254
3255	flags_in = fi_args->flags;
3256	memset(fi_args, 0, sizeof(*fi_args));
3257
3258	rcu_read_lock();
3259	fi_args->num_devices = fs_devices->num_devices;
 
3260
3261	list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
3262		if (device->devid > fi_args->max_id)
3263			fi_args->max_id = device->devid;
3264	}
3265	rcu_read_unlock();
3266
3267	memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
3268	fi_args->nodesize = fs_info->nodesize;
3269	fi_args->sectorsize = fs_info->sectorsize;
3270	fi_args->clone_alignment = fs_info->sectorsize;
3271
3272	if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
3273		fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
3274		fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
3275		fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
3276	}
3277
3278	if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
3279		fi_args->generation = fs_info->generation;
3280		fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
3281	}
3282
3283	if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
3284		memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
3285		       sizeof(fi_args->metadata_uuid));
3286		fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
3287	}
3288
3289	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
3290		ret = -EFAULT;
3291
3292	kfree(fi_args);
3293	return ret;
3294}
3295
3296static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
3297				 void __user *arg)
3298{
3299	struct btrfs_ioctl_dev_info_args *di_args;
3300	struct btrfs_device *dev;
 
3301	int ret = 0;
3302	char *s_uuid = NULL;
3303
3304	di_args = memdup_user(arg, sizeof(*di_args));
3305	if (IS_ERR(di_args))
3306		return PTR_ERR(di_args);
3307
3308	if (!btrfs_is_empty_uuid(di_args->uuid))
3309		s_uuid = di_args->uuid;
3310
3311	rcu_read_lock();
3312	dev = btrfs_find_device(fs_info->fs_devices, di_args->devid, s_uuid,
3313				NULL, true);
3314
3315	if (!dev) {
3316		ret = -ENODEV;
3317		goto out;
3318	}
3319
3320	di_args->devid = dev->devid;
3321	di_args->bytes_used = btrfs_device_get_bytes_used(dev);
3322	di_args->total_bytes = btrfs_device_get_total_bytes(dev);
3323	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
3324	if (dev->name) {
3325		strncpy(di_args->path, rcu_str_deref(dev->name),
3326				sizeof(di_args->path) - 1);
 
 
 
 
3327		di_args->path[sizeof(di_args->path) - 1] = 0;
3328	} else {
3329		di_args->path[0] = '\0';
3330	}
3331
3332out:
3333	rcu_read_unlock();
3334	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
3335		ret = -EFAULT;
3336
3337	kfree(di_args);
3338	return ret;
3339}
3340
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3341static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
3342{
3343	struct inode *inode = file_inode(file);
3344	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3345	struct btrfs_root *root = BTRFS_I(inode)->root;
3346	struct btrfs_root *new_root;
3347	struct btrfs_dir_item *di;
3348	struct btrfs_trans_handle *trans;
3349	struct btrfs_path *path = NULL;
 
3350	struct btrfs_disk_key disk_key;
3351	u64 objectid = 0;
3352	u64 dir_id;
3353	int ret;
3354
3355	if (!capable(CAP_SYS_ADMIN))
3356		return -EPERM;
3357
3358	ret = mnt_want_write_file(file);
3359	if (ret)
3360		return ret;
3361
3362	if (copy_from_user(&objectid, argp, sizeof(objectid))) {
3363		ret = -EFAULT;
3364		goto out;
3365	}
3366
3367	if (!objectid)
3368		objectid = BTRFS_FS_TREE_OBJECTID;
3369
3370	new_root = btrfs_get_fs_root(fs_info, objectid, true);
 
 
 
 
3371	if (IS_ERR(new_root)) {
3372		ret = PTR_ERR(new_root);
3373		goto out;
3374	}
3375	if (!is_fstree(new_root->root_key.objectid)) {
3376		ret = -ENOENT;
3377		goto out_free;
3378	}
3379
3380	path = btrfs_alloc_path();
3381	if (!path) {
3382		ret = -ENOMEM;
3383		goto out_free;
3384	}
3385	path->leave_spinning = 1;
3386
3387	trans = btrfs_start_transaction(root, 1);
3388	if (IS_ERR(trans)) {
 
3389		ret = PTR_ERR(trans);
3390		goto out_free;
3391	}
3392
3393	dir_id = btrfs_super_root_dir(fs_info->super_copy);
3394	di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
3395				   dir_id, "default", 7, 1);
3396	if (IS_ERR_OR_NULL(di)) {
3397		btrfs_release_path(path);
3398		btrfs_end_transaction(trans);
3399		btrfs_err(fs_info,
3400			  "Umm, you don't have the default diritem, this isn't going to work");
3401		ret = -ENOENT;
3402		goto out_free;
3403	}
3404
3405	btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
3406	btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
3407	btrfs_mark_buffer_dirty(path->nodes[0]);
3408	btrfs_release_path(path);
3409
3410	btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
3411	btrfs_end_transaction(trans);
3412out_free:
3413	btrfs_put_root(new_root);
3414	btrfs_free_path(path);
3415out:
3416	mnt_drop_write_file(file);
3417	return ret;
3418}
3419
3420static void get_block_group_info(struct list_head *groups_list,
3421				 struct btrfs_ioctl_space_info *space)
3422{
3423	struct btrfs_block_group *block_group;
3424
3425	space->total_bytes = 0;
3426	space->used_bytes = 0;
3427	space->flags = 0;
3428	list_for_each_entry(block_group, groups_list, list) {
3429		space->flags = block_group->flags;
3430		space->total_bytes += block_group->length;
3431		space->used_bytes += block_group->used;
 
3432	}
3433}
3434
3435static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
3436				   void __user *arg)
3437{
3438	struct btrfs_ioctl_space_args space_args;
3439	struct btrfs_ioctl_space_info space;
3440	struct btrfs_ioctl_space_info *dest;
3441	struct btrfs_ioctl_space_info *dest_orig;
3442	struct btrfs_ioctl_space_info __user *user_dest;
3443	struct btrfs_space_info *info;
3444	static const u64 types[] = {
3445		BTRFS_BLOCK_GROUP_DATA,
3446		BTRFS_BLOCK_GROUP_SYSTEM,
3447		BTRFS_BLOCK_GROUP_METADATA,
3448		BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
3449	};
3450	int num_types = 4;
3451	int alloc_size;
3452	int ret = 0;
3453	u64 slot_count = 0;
3454	int i, c;
3455
3456	if (copy_from_user(&space_args,
3457			   (struct btrfs_ioctl_space_args __user *)arg,
3458			   sizeof(space_args)))
3459		return -EFAULT;
3460
3461	for (i = 0; i < num_types; i++) {
3462		struct btrfs_space_info *tmp;
3463
3464		info = NULL;
3465		rcu_read_lock();
3466		list_for_each_entry_rcu(tmp, &fs_info->space_info,
3467					list) {
3468			if (tmp->flags == types[i]) {
3469				info = tmp;
3470				break;
3471			}
3472		}
3473		rcu_read_unlock();
3474
3475		if (!info)
3476			continue;
3477
3478		down_read(&info->groups_sem);
3479		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3480			if (!list_empty(&info->block_groups[c]))
3481				slot_count++;
3482		}
3483		up_read(&info->groups_sem);
3484	}
3485
3486	/*
3487	 * Global block reserve, exported as a space_info
3488	 */
3489	slot_count++;
3490
3491	/* space_slots == 0 means they are asking for a count */
3492	if (space_args.space_slots == 0) {
3493		space_args.total_spaces = slot_count;
3494		goto out;
3495	}
3496
3497	slot_count = min_t(u64, space_args.space_slots, slot_count);
3498
3499	alloc_size = sizeof(*dest) * slot_count;
3500
3501	/* we generally have at most 6 or so space infos, one for each raid
3502	 * level.  So, a whole page should be more than enough for everyone
3503	 */
3504	if (alloc_size > PAGE_SIZE)
3505		return -ENOMEM;
3506
3507	space_args.total_spaces = 0;
3508	dest = kmalloc(alloc_size, GFP_KERNEL);
3509	if (!dest)
3510		return -ENOMEM;
3511	dest_orig = dest;
3512
3513	/* now we have a buffer to copy into */
3514	for (i = 0; i < num_types; i++) {
3515		struct btrfs_space_info *tmp;
3516
3517		if (!slot_count)
3518			break;
3519
3520		info = NULL;
3521		rcu_read_lock();
3522		list_for_each_entry_rcu(tmp, &fs_info->space_info,
3523					list) {
3524			if (tmp->flags == types[i]) {
3525				info = tmp;
3526				break;
3527			}
3528		}
3529		rcu_read_unlock();
3530
3531		if (!info)
3532			continue;
3533		down_read(&info->groups_sem);
3534		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3535			if (!list_empty(&info->block_groups[c])) {
3536				get_block_group_info(&info->block_groups[c],
3537						     &space);
3538				memcpy(dest, &space, sizeof(space));
3539				dest++;
3540				space_args.total_spaces++;
3541				slot_count--;
3542			}
3543			if (!slot_count)
3544				break;
3545		}
3546		up_read(&info->groups_sem);
3547	}
3548
3549	/*
3550	 * Add global block reserve
3551	 */
3552	if (slot_count) {
3553		struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3554
3555		spin_lock(&block_rsv->lock);
3556		space.total_bytes = block_rsv->size;
3557		space.used_bytes = block_rsv->size - block_rsv->reserved;
3558		spin_unlock(&block_rsv->lock);
3559		space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3560		memcpy(dest, &space, sizeof(space));
3561		space_args.total_spaces++;
3562	}
3563
3564	user_dest = (struct btrfs_ioctl_space_info __user *)
3565		(arg + sizeof(struct btrfs_ioctl_space_args));
3566
3567	if (copy_to_user(user_dest, dest_orig, alloc_size))
3568		ret = -EFAULT;
3569
3570	kfree(dest_orig);
3571out:
3572	if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3573		ret = -EFAULT;
3574
3575	return ret;
3576}
3577
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3578static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3579					    void __user *argp)
3580{
3581	struct btrfs_trans_handle *trans;
3582	u64 transid;
3583	int ret;
3584
3585	trans = btrfs_attach_transaction_barrier(root);
3586	if (IS_ERR(trans)) {
3587		if (PTR_ERR(trans) != -ENOENT)
3588			return PTR_ERR(trans);
3589
3590		/* No running transaction, don't bother */
3591		transid = root->fs_info->last_trans_committed;
3592		goto out;
3593	}
3594	transid = trans->transid;
3595	ret = btrfs_commit_transaction_async(trans, 0);
3596	if (ret) {
3597		btrfs_end_transaction(trans);
3598		return ret;
3599	}
3600out:
3601	if (argp)
3602		if (copy_to_user(argp, &transid, sizeof(transid)))
3603			return -EFAULT;
3604	return 0;
3605}
3606
3607static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
3608					   void __user *argp)
3609{
3610	u64 transid;
3611
3612	if (argp) {
3613		if (copy_from_user(&transid, argp, sizeof(transid)))
3614			return -EFAULT;
3615	} else {
3616		transid = 0;  /* current trans */
3617	}
3618	return btrfs_wait_for_commit(fs_info, transid);
3619}
3620
3621static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3622{
3623	struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
3624	struct btrfs_ioctl_scrub_args *sa;
3625	int ret;
3626
3627	if (!capable(CAP_SYS_ADMIN))
3628		return -EPERM;
3629
3630	sa = memdup_user(arg, sizeof(*sa));
3631	if (IS_ERR(sa))
3632		return PTR_ERR(sa);
3633
3634	if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3635		ret = mnt_want_write_file(file);
3636		if (ret)
3637			goto out;
3638	}
3639
3640	ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
3641			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3642			      0);
3643
3644	/*
3645	 * Copy scrub args to user space even if btrfs_scrub_dev() returned an
3646	 * error. This is important as it allows user space to know how much
3647	 * progress scrub has done. For example, if scrub is canceled we get
3648	 * -ECANCELED from btrfs_scrub_dev() and return that error back to user
3649	 * space. Later user space can inspect the progress from the structure
3650	 * btrfs_ioctl_scrub_args and resume scrub from where it left off
3651	 * previously (btrfs-progs does this).
3652	 * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
3653	 * then return -EFAULT to signal the structure was not copied or it may
3654	 * be corrupt and unreliable due to a partial copy.
3655	 */
3656	if (copy_to_user(arg, sa, sizeof(*sa)))
3657		ret = -EFAULT;
3658
3659	if (!(sa->flags & BTRFS_SCRUB_READONLY))
3660		mnt_drop_write_file(file);
3661out:
3662	kfree(sa);
3663	return ret;
3664}
3665
3666static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
3667{
3668	if (!capable(CAP_SYS_ADMIN))
3669		return -EPERM;
3670
3671	return btrfs_scrub_cancel(fs_info);
3672}
3673
3674static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
3675				       void __user *arg)
3676{
3677	struct btrfs_ioctl_scrub_args *sa;
3678	int ret;
3679
3680	if (!capable(CAP_SYS_ADMIN))
3681		return -EPERM;
3682
3683	sa = memdup_user(arg, sizeof(*sa));
3684	if (IS_ERR(sa))
3685		return PTR_ERR(sa);
3686
3687	ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
3688
3689	if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3690		ret = -EFAULT;
3691
3692	kfree(sa);
3693	return ret;
3694}
3695
3696static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
3697				      void __user *arg)
3698{
3699	struct btrfs_ioctl_get_dev_stats *sa;
3700	int ret;
3701
3702	sa = memdup_user(arg, sizeof(*sa));
3703	if (IS_ERR(sa))
3704		return PTR_ERR(sa);
3705
3706	if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3707		kfree(sa);
3708		return -EPERM;
3709	}
3710
3711	ret = btrfs_get_dev_stats(fs_info, sa);
3712
3713	if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3714		ret = -EFAULT;
3715
3716	kfree(sa);
3717	return ret;
3718}
3719
3720static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
3721				    void __user *arg)
3722{
3723	struct btrfs_ioctl_dev_replace_args *p;
3724	int ret;
3725
3726	if (!capable(CAP_SYS_ADMIN))
3727		return -EPERM;
3728
3729	p = memdup_user(arg, sizeof(*p));
3730	if (IS_ERR(p))
3731		return PTR_ERR(p);
3732
3733	switch (p->cmd) {
3734	case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3735		if (sb_rdonly(fs_info->sb)) {
3736			ret = -EROFS;
3737			goto out;
3738		}
3739		if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
 
3740			ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3741		} else {
3742			ret = btrfs_dev_replace_by_ioctl(fs_info, p);
3743			clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
 
3744		}
3745		break;
3746	case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3747		btrfs_dev_replace_status(fs_info, p);
3748		ret = 0;
3749		break;
3750	case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3751		p->result = btrfs_dev_replace_cancel(fs_info);
3752		ret = 0;
3753		break;
3754	default:
3755		ret = -EINVAL;
3756		break;
3757	}
3758
3759	if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
3760		ret = -EFAULT;
3761out:
3762	kfree(p);
3763	return ret;
3764}
3765
3766static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3767{
3768	int ret = 0;
3769	int i;
3770	u64 rel_ptr;
3771	int size;
3772	struct btrfs_ioctl_ino_path_args *ipa = NULL;
3773	struct inode_fs_paths *ipath = NULL;
3774	struct btrfs_path *path;
3775
3776	if (!capable(CAP_DAC_READ_SEARCH))
3777		return -EPERM;
3778
3779	path = btrfs_alloc_path();
3780	if (!path) {
3781		ret = -ENOMEM;
3782		goto out;
3783	}
3784
3785	ipa = memdup_user(arg, sizeof(*ipa));
3786	if (IS_ERR(ipa)) {
3787		ret = PTR_ERR(ipa);
3788		ipa = NULL;
3789		goto out;
3790	}
3791
3792	size = min_t(u32, ipa->size, 4096);
3793	ipath = init_ipath(size, root, path);
3794	if (IS_ERR(ipath)) {
3795		ret = PTR_ERR(ipath);
3796		ipath = NULL;
3797		goto out;
3798	}
3799
3800	ret = paths_from_inode(ipa->inum, ipath);
3801	if (ret < 0)
3802		goto out;
3803
3804	for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3805		rel_ptr = ipath->fspath->val[i] -
3806			  (u64)(unsigned long)ipath->fspath->val;
3807		ipath->fspath->val[i] = rel_ptr;
3808	}
3809
3810	ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
3811			   ipath->fspath, size);
3812	if (ret) {
3813		ret = -EFAULT;
3814		goto out;
3815	}
3816
3817out:
3818	btrfs_free_path(path);
3819	free_ipath(ipath);
3820	kfree(ipa);
3821
3822	return ret;
3823}
3824
3825static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3826{
3827	struct btrfs_data_container *inodes = ctx;
3828	const size_t c = 3 * sizeof(u64);
3829
3830	if (inodes->bytes_left >= c) {
3831		inodes->bytes_left -= c;
3832		inodes->val[inodes->elem_cnt] = inum;
3833		inodes->val[inodes->elem_cnt + 1] = offset;
3834		inodes->val[inodes->elem_cnt + 2] = root;
3835		inodes->elem_cnt += 3;
3836	} else {
3837		inodes->bytes_missing += c - inodes->bytes_left;
3838		inodes->bytes_left = 0;
3839		inodes->elem_missed += 3;
3840	}
3841
3842	return 0;
3843}
3844
3845static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
3846					void __user *arg, int version)
3847{
3848	int ret = 0;
3849	int size;
3850	struct btrfs_ioctl_logical_ino_args *loi;
3851	struct btrfs_data_container *inodes = NULL;
3852	struct btrfs_path *path = NULL;
3853	bool ignore_offset;
3854
3855	if (!capable(CAP_SYS_ADMIN))
3856		return -EPERM;
3857
3858	loi = memdup_user(arg, sizeof(*loi));
3859	if (IS_ERR(loi))
3860		return PTR_ERR(loi);
3861
3862	if (version == 1) {
3863		ignore_offset = false;
3864		size = min_t(u32, loi->size, SZ_64K);
3865	} else {
3866		/* All reserved bits must be 0 for now */
3867		if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
3868			ret = -EINVAL;
3869			goto out_loi;
3870		}
3871		/* Only accept flags we have defined so far */
3872		if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
3873			ret = -EINVAL;
3874			goto out_loi;
3875		}
3876		ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
3877		size = min_t(u32, loi->size, SZ_16M);
3878	}
3879
3880	path = btrfs_alloc_path();
3881	if (!path) {
3882		ret = -ENOMEM;
3883		goto out;
3884	}
3885
 
3886	inodes = init_data_container(size);
3887	if (IS_ERR(inodes)) {
3888		ret = PTR_ERR(inodes);
3889		inodes = NULL;
3890		goto out;
3891	}
3892
3893	ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
3894					  build_ino_list, inodes, ignore_offset);
3895	if (ret == -EINVAL)
3896		ret = -ENOENT;
3897	if (ret < 0)
3898		goto out;
3899
3900	ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
3901			   size);
3902	if (ret)
3903		ret = -EFAULT;
3904
3905out:
3906	btrfs_free_path(path);
3907	kvfree(inodes);
3908out_loi:
3909	kfree(loi);
3910
3911	return ret;
3912}
3913
3914void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
3915			       struct btrfs_ioctl_balance_args *bargs)
3916{
3917	struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3918
3919	bargs->flags = bctl->flags;
3920
3921	if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
3922		bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3923	if (atomic_read(&fs_info->balance_pause_req))
3924		bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3925	if (atomic_read(&fs_info->balance_cancel_req))
3926		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3927
3928	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3929	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3930	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3931
3932	spin_lock(&fs_info->balance_lock);
3933	memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3934	spin_unlock(&fs_info->balance_lock);
 
 
 
 
3935}
3936
3937static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3938{
3939	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3940	struct btrfs_fs_info *fs_info = root->fs_info;
3941	struct btrfs_ioctl_balance_args *bargs;
3942	struct btrfs_balance_control *bctl;
3943	bool need_unlock; /* for mut. excl. ops lock */
3944	int ret;
3945
3946	if (!capable(CAP_SYS_ADMIN))
3947		return -EPERM;
3948
3949	ret = mnt_want_write_file(file);
3950	if (ret)
3951		return ret;
3952
3953again:
3954	if (!test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
 
3955		mutex_lock(&fs_info->balance_mutex);
3956		need_unlock = true;
3957		goto locked;
3958	}
3959
3960	/*
3961	 * mut. excl. ops lock is locked.  Three possibilities:
3962	 *   (1) some other op is running
3963	 *   (2) balance is running
3964	 *   (3) balance is paused -- special case (think resume)
3965	 */
3966	mutex_lock(&fs_info->balance_mutex);
3967	if (fs_info->balance_ctl) {
3968		/* this is either (2) or (3) */
3969		if (!test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3970			mutex_unlock(&fs_info->balance_mutex);
3971			/*
3972			 * Lock released to allow other waiters to continue,
3973			 * we'll reexamine the status again.
3974			 */
3975			mutex_lock(&fs_info->balance_mutex);
3976
3977			if (fs_info->balance_ctl &&
3978			    !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3979				/* this is (3) */
3980				need_unlock = false;
3981				goto locked;
3982			}
3983
3984			mutex_unlock(&fs_info->balance_mutex);
 
3985			goto again;
3986		} else {
3987			/* this is (2) */
3988			mutex_unlock(&fs_info->balance_mutex);
3989			ret = -EINPROGRESS;
3990			goto out;
3991		}
3992	} else {
3993		/* this is (1) */
3994		mutex_unlock(&fs_info->balance_mutex);
3995		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3996		goto out;
3997	}
3998
3999locked:
4000	BUG_ON(!test_bit(BTRFS_FS_EXCL_OP, &fs_info->flags));
4001
4002	if (arg) {
4003		bargs = memdup_user(arg, sizeof(*bargs));
4004		if (IS_ERR(bargs)) {
4005			ret = PTR_ERR(bargs);
4006			goto out_unlock;
4007		}
4008
4009		if (bargs->flags & BTRFS_BALANCE_RESUME) {
4010			if (!fs_info->balance_ctl) {
4011				ret = -ENOTCONN;
4012				goto out_bargs;
4013			}
4014
4015			bctl = fs_info->balance_ctl;
4016			spin_lock(&fs_info->balance_lock);
4017			bctl->flags |= BTRFS_BALANCE_RESUME;
4018			spin_unlock(&fs_info->balance_lock);
4019
4020			goto do_balance;
4021		}
4022	} else {
4023		bargs = NULL;
4024	}
4025
4026	if (fs_info->balance_ctl) {
4027		ret = -EINPROGRESS;
4028		goto out_bargs;
4029	}
4030
4031	bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
4032	if (!bctl) {
4033		ret = -ENOMEM;
4034		goto out_bargs;
4035	}
4036
 
4037	if (arg) {
4038		memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
4039		memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
4040		memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
4041
4042		bctl->flags = bargs->flags;
4043	} else {
4044		/* balance everything - no filters */
4045		bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
4046	}
4047
4048	if (bctl->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
4049		ret = -EINVAL;
4050		goto out_bctl;
4051	}
4052
4053do_balance:
4054	/*
4055	 * Ownership of bctl and filesystem flag BTRFS_FS_EXCL_OP goes to
4056	 * btrfs_balance.  bctl is freed in reset_balance_state, or, if
4057	 * restriper was paused all the way until unmount, in free_fs_info.
4058	 * The flag should be cleared after reset_balance_state.
 
4059	 */
4060	need_unlock = false;
4061
4062	ret = btrfs_balance(fs_info, bctl, bargs);
4063	bctl = NULL;
4064
4065	if ((ret == 0 || ret == -ECANCELED) && arg) {
4066		if (copy_to_user(arg, bargs, sizeof(*bargs)))
4067			ret = -EFAULT;
4068	}
4069
4070out_bctl:
4071	kfree(bctl);
4072out_bargs:
4073	kfree(bargs);
4074out_unlock:
4075	mutex_unlock(&fs_info->balance_mutex);
 
4076	if (need_unlock)
4077		clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
4078out:
4079	mnt_drop_write_file(file);
4080	return ret;
4081}
4082
4083static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
4084{
4085	if (!capable(CAP_SYS_ADMIN))
4086		return -EPERM;
4087
4088	switch (cmd) {
4089	case BTRFS_BALANCE_CTL_PAUSE:
4090		return btrfs_pause_balance(fs_info);
4091	case BTRFS_BALANCE_CTL_CANCEL:
4092		return btrfs_cancel_balance(fs_info);
4093	}
4094
4095	return -EINVAL;
4096}
4097
4098static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
4099					 void __user *arg)
4100{
4101	struct btrfs_ioctl_balance_args *bargs;
4102	int ret = 0;
4103
4104	if (!capable(CAP_SYS_ADMIN))
4105		return -EPERM;
4106
4107	mutex_lock(&fs_info->balance_mutex);
4108	if (!fs_info->balance_ctl) {
4109		ret = -ENOTCONN;
4110		goto out;
4111	}
4112
4113	bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
4114	if (!bargs) {
4115		ret = -ENOMEM;
4116		goto out;
4117	}
4118
4119	btrfs_update_ioctl_balance_args(fs_info, bargs);
4120
4121	if (copy_to_user(arg, bargs, sizeof(*bargs)))
4122		ret = -EFAULT;
4123
4124	kfree(bargs);
4125out:
4126	mutex_unlock(&fs_info->balance_mutex);
4127	return ret;
4128}
4129
4130static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
4131{
4132	struct inode *inode = file_inode(file);
4133	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4134	struct btrfs_ioctl_quota_ctl_args *sa;
 
4135	int ret;
 
4136
4137	if (!capable(CAP_SYS_ADMIN))
4138		return -EPERM;
4139
4140	ret = mnt_want_write_file(file);
4141	if (ret)
4142		return ret;
4143
4144	sa = memdup_user(arg, sizeof(*sa));
4145	if (IS_ERR(sa)) {
4146		ret = PTR_ERR(sa);
4147		goto drop_write;
4148	}
4149
4150	down_write(&fs_info->subvol_sem);
 
 
 
 
 
4151
4152	switch (sa->cmd) {
4153	case BTRFS_QUOTA_CTL_ENABLE:
4154		ret = btrfs_quota_enable(fs_info);
4155		break;
4156	case BTRFS_QUOTA_CTL_DISABLE:
4157		ret = btrfs_quota_disable(fs_info);
4158		break;
4159	default:
4160		ret = -EINVAL;
4161		break;
4162	}
4163
 
 
 
 
4164	kfree(sa);
4165	up_write(&fs_info->subvol_sem);
4166drop_write:
4167	mnt_drop_write_file(file);
4168	return ret;
4169}
4170
4171static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
4172{
4173	struct inode *inode = file_inode(file);
4174	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4175	struct btrfs_root *root = BTRFS_I(inode)->root;
4176	struct btrfs_ioctl_qgroup_assign_args *sa;
4177	struct btrfs_trans_handle *trans;
4178	int ret;
4179	int err;
4180
4181	if (!capable(CAP_SYS_ADMIN))
4182		return -EPERM;
4183
4184	ret = mnt_want_write_file(file);
4185	if (ret)
4186		return ret;
4187
4188	sa = memdup_user(arg, sizeof(*sa));
4189	if (IS_ERR(sa)) {
4190		ret = PTR_ERR(sa);
4191		goto drop_write;
4192	}
4193
4194	trans = btrfs_join_transaction(root);
4195	if (IS_ERR(trans)) {
4196		ret = PTR_ERR(trans);
4197		goto out;
4198	}
4199
 
4200	if (sa->assign) {
4201		ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
 
4202	} else {
4203		ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
 
4204	}
4205
4206	/* update qgroup status and info */
4207	err = btrfs_run_qgroups(trans);
4208	if (err < 0)
4209		btrfs_handle_fs_error(fs_info, err,
4210				      "failed to update qgroup status and info");
4211	err = btrfs_end_transaction(trans);
4212	if (err && !ret)
4213		ret = err;
4214
4215out:
4216	kfree(sa);
4217drop_write:
4218	mnt_drop_write_file(file);
4219	return ret;
4220}
4221
4222static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
4223{
4224	struct inode *inode = file_inode(file);
 
4225	struct btrfs_root *root = BTRFS_I(inode)->root;
4226	struct btrfs_ioctl_qgroup_create_args *sa;
4227	struct btrfs_trans_handle *trans;
4228	int ret;
4229	int err;
4230
4231	if (!capable(CAP_SYS_ADMIN))
4232		return -EPERM;
4233
4234	ret = mnt_want_write_file(file);
4235	if (ret)
4236		return ret;
4237
4238	sa = memdup_user(arg, sizeof(*sa));
4239	if (IS_ERR(sa)) {
4240		ret = PTR_ERR(sa);
4241		goto drop_write;
4242	}
4243
4244	if (!sa->qgroupid) {
4245		ret = -EINVAL;
4246		goto out;
4247	}
4248
4249	trans = btrfs_join_transaction(root);
4250	if (IS_ERR(trans)) {
4251		ret = PTR_ERR(trans);
4252		goto out;
4253	}
4254
 
4255	if (sa->create) {
4256		ret = btrfs_create_qgroup(trans, sa->qgroupid);
4257	} else {
4258		ret = btrfs_remove_qgroup(trans, sa->qgroupid);
4259	}
4260
4261	err = btrfs_end_transaction(trans);
4262	if (err && !ret)
4263		ret = err;
4264
4265out:
4266	kfree(sa);
4267drop_write:
4268	mnt_drop_write_file(file);
4269	return ret;
4270}
4271
4272static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
4273{
4274	struct inode *inode = file_inode(file);
 
4275	struct btrfs_root *root = BTRFS_I(inode)->root;
4276	struct btrfs_ioctl_qgroup_limit_args *sa;
4277	struct btrfs_trans_handle *trans;
4278	int ret;
4279	int err;
4280	u64 qgroupid;
4281
4282	if (!capable(CAP_SYS_ADMIN))
4283		return -EPERM;
4284
4285	ret = mnt_want_write_file(file);
4286	if (ret)
4287		return ret;
4288
4289	sa = memdup_user(arg, sizeof(*sa));
4290	if (IS_ERR(sa)) {
4291		ret = PTR_ERR(sa);
4292		goto drop_write;
4293	}
4294
4295	trans = btrfs_join_transaction(root);
4296	if (IS_ERR(trans)) {
4297		ret = PTR_ERR(trans);
4298		goto out;
4299	}
4300
4301	qgroupid = sa->qgroupid;
4302	if (!qgroupid) {
4303		/* take the current subvol as qgroup */
4304		qgroupid = root->root_key.objectid;
4305	}
4306
4307	ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
 
4308
4309	err = btrfs_end_transaction(trans);
4310	if (err && !ret)
4311		ret = err;
4312
4313out:
4314	kfree(sa);
4315drop_write:
4316	mnt_drop_write_file(file);
4317	return ret;
4318}
4319
4320static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
4321{
4322	struct inode *inode = file_inode(file);
4323	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4324	struct btrfs_ioctl_quota_rescan_args *qsa;
4325	int ret;
4326
4327	if (!capable(CAP_SYS_ADMIN))
4328		return -EPERM;
4329
4330	ret = mnt_want_write_file(file);
4331	if (ret)
4332		return ret;
4333
4334	qsa = memdup_user(arg, sizeof(*qsa));
4335	if (IS_ERR(qsa)) {
4336		ret = PTR_ERR(qsa);
4337		goto drop_write;
4338	}
4339
4340	if (qsa->flags) {
4341		ret = -EINVAL;
4342		goto out;
4343	}
4344
4345	ret = btrfs_qgroup_rescan(fs_info);
4346
4347out:
4348	kfree(qsa);
4349drop_write:
4350	mnt_drop_write_file(file);
4351	return ret;
4352}
4353
4354static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
4355						void __user *arg)
4356{
 
 
4357	struct btrfs_ioctl_quota_rescan_args *qsa;
4358	int ret = 0;
4359
4360	if (!capable(CAP_SYS_ADMIN))
4361		return -EPERM;
4362
4363	qsa = kzalloc(sizeof(*qsa), GFP_KERNEL);
4364	if (!qsa)
4365		return -ENOMEM;
4366
4367	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
4368		qsa->flags = 1;
4369		qsa->progress = fs_info->qgroup_rescan_progress.objectid;
4370	}
4371
4372	if (copy_to_user(arg, qsa, sizeof(*qsa)))
4373		ret = -EFAULT;
4374
4375	kfree(qsa);
4376	return ret;
4377}
4378
4379static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
4380						void __user *arg)
4381{
 
 
 
4382	if (!capable(CAP_SYS_ADMIN))
4383		return -EPERM;
4384
4385	return btrfs_qgroup_wait_for_completion(fs_info, true);
4386}
4387
4388static long _btrfs_ioctl_set_received_subvol(struct file *file,
4389					    struct btrfs_ioctl_received_subvol_args *sa)
4390{
4391	struct inode *inode = file_inode(file);
4392	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4393	struct btrfs_root *root = BTRFS_I(inode)->root;
4394	struct btrfs_root_item *root_item = &root->root_item;
4395	struct btrfs_trans_handle *trans;
4396	struct timespec64 ct = current_time(inode);
4397	int ret = 0;
4398	int received_uuid_changed;
4399
4400	if (!inode_owner_or_capable(inode))
4401		return -EPERM;
4402
4403	ret = mnt_want_write_file(file);
4404	if (ret < 0)
4405		return ret;
4406
4407	down_write(&fs_info->subvol_sem);
4408
4409	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
4410		ret = -EINVAL;
4411		goto out;
4412	}
4413
4414	if (btrfs_root_readonly(root)) {
4415		ret = -EROFS;
4416		goto out;
4417	}
4418
4419	/*
4420	 * 1 - root item
4421	 * 2 - uuid items (received uuid + subvol uuid)
4422	 */
4423	trans = btrfs_start_transaction(root, 3);
4424	if (IS_ERR(trans)) {
4425		ret = PTR_ERR(trans);
4426		trans = NULL;
4427		goto out;
4428	}
4429
4430	sa->rtransid = trans->transid;
4431	sa->rtime.sec = ct.tv_sec;
4432	sa->rtime.nsec = ct.tv_nsec;
4433
4434	received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
4435				       BTRFS_UUID_SIZE);
4436	if (received_uuid_changed &&
4437	    !btrfs_is_empty_uuid(root_item->received_uuid)) {
4438		ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
4439					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4440					  root->root_key.objectid);
4441		if (ret && ret != -ENOENT) {
4442		        btrfs_abort_transaction(trans, ret);
4443		        btrfs_end_transaction(trans);
4444		        goto out;
4445		}
4446	}
4447	memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
4448	btrfs_set_root_stransid(root_item, sa->stransid);
4449	btrfs_set_root_rtransid(root_item, sa->rtransid);
4450	btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
4451	btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
4452	btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
4453	btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4454
4455	ret = btrfs_update_root(trans, fs_info->tree_root,
4456				&root->root_key, &root->root_item);
4457	if (ret < 0) {
4458		btrfs_end_transaction(trans);
4459		goto out;
4460	}
4461	if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
4462		ret = btrfs_uuid_tree_add(trans, sa->uuid,
4463					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
4464					  root->root_key.objectid);
4465		if (ret < 0 && ret != -EEXIST) {
4466			btrfs_abort_transaction(trans, ret);
4467			btrfs_end_transaction(trans);
4468			goto out;
4469		}
4470	}
4471	ret = btrfs_commit_transaction(trans);
 
 
 
 
 
4472out:
4473	up_write(&fs_info->subvol_sem);
4474	mnt_drop_write_file(file);
4475	return ret;
4476}
4477
4478#ifdef CONFIG_64BIT
4479static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4480						void __user *arg)
4481{
4482	struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4483	struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4484	int ret = 0;
4485
4486	args32 = memdup_user(arg, sizeof(*args32));
4487	if (IS_ERR(args32))
4488		return PTR_ERR(args32);
4489
4490	args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
4491	if (!args64) {
4492		ret = -ENOMEM;
4493		goto out;
4494	}
4495
4496	memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4497	args64->stransid = args32->stransid;
4498	args64->rtransid = args32->rtransid;
4499	args64->stime.sec = args32->stime.sec;
4500	args64->stime.nsec = args32->stime.nsec;
4501	args64->rtime.sec = args32->rtime.sec;
4502	args64->rtime.nsec = args32->rtime.nsec;
4503	args64->flags = args32->flags;
4504
4505	ret = _btrfs_ioctl_set_received_subvol(file, args64);
4506	if (ret)
4507		goto out;
4508
4509	memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4510	args32->stransid = args64->stransid;
4511	args32->rtransid = args64->rtransid;
4512	args32->stime.sec = args64->stime.sec;
4513	args32->stime.nsec = args64->stime.nsec;
4514	args32->rtime.sec = args64->rtime.sec;
4515	args32->rtime.nsec = args64->rtime.nsec;
4516	args32->flags = args64->flags;
4517
4518	ret = copy_to_user(arg, args32, sizeof(*args32));
4519	if (ret)
4520		ret = -EFAULT;
4521
4522out:
4523	kfree(args32);
4524	kfree(args64);
4525	return ret;
4526}
4527#endif
4528
4529static long btrfs_ioctl_set_received_subvol(struct file *file,
4530					    void __user *arg)
4531{
4532	struct btrfs_ioctl_received_subvol_args *sa = NULL;
4533	int ret = 0;
4534
4535	sa = memdup_user(arg, sizeof(*sa));
4536	if (IS_ERR(sa))
4537		return PTR_ERR(sa);
4538
4539	ret = _btrfs_ioctl_set_received_subvol(file, sa);
4540
4541	if (ret)
4542		goto out;
4543
4544	ret = copy_to_user(arg, sa, sizeof(*sa));
4545	if (ret)
4546		ret = -EFAULT;
4547
4548out:
4549	kfree(sa);
4550	return ret;
4551}
4552
4553static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
4554					void __user *arg)
4555{
 
 
4556	size_t len;
4557	int ret;
4558	char label[BTRFS_LABEL_SIZE];
4559
4560	spin_lock(&fs_info->super_lock);
4561	memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4562	spin_unlock(&fs_info->super_lock);
4563
4564	len = strnlen(label, BTRFS_LABEL_SIZE);
4565
4566	if (len == BTRFS_LABEL_SIZE) {
4567		btrfs_warn(fs_info,
4568			   "label is too long, return the first %zu bytes",
4569			   --len);
4570	}
4571
4572	ret = copy_to_user(arg, label, len);
4573
4574	return ret ? -EFAULT : 0;
4575}
4576
4577static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4578{
4579	struct inode *inode = file_inode(file);
4580	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4581	struct btrfs_root *root = BTRFS_I(inode)->root;
4582	struct btrfs_super_block *super_block = fs_info->super_copy;
4583	struct btrfs_trans_handle *trans;
4584	char label[BTRFS_LABEL_SIZE];
4585	int ret;
4586
4587	if (!capable(CAP_SYS_ADMIN))
4588		return -EPERM;
4589
4590	if (copy_from_user(label, arg, sizeof(label)))
4591		return -EFAULT;
4592
4593	if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4594		btrfs_err(fs_info,
4595			  "unable to set label with more than %d bytes",
4596			  BTRFS_LABEL_SIZE - 1);
4597		return -EINVAL;
4598	}
4599
4600	ret = mnt_want_write_file(file);
4601	if (ret)
4602		return ret;
4603
4604	trans = btrfs_start_transaction(root, 0);
4605	if (IS_ERR(trans)) {
4606		ret = PTR_ERR(trans);
4607		goto out_unlock;
4608	}
4609
4610	spin_lock(&fs_info->super_lock);
4611	strcpy(super_block->label, label);
4612	spin_unlock(&fs_info->super_lock);
4613	ret = btrfs_commit_transaction(trans);
4614
4615out_unlock:
4616	mnt_drop_write_file(file);
4617	return ret;
4618}
4619
4620#define INIT_FEATURE_FLAGS(suffix) \
4621	{ .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4622	  .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4623	  .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4624
4625int btrfs_ioctl_get_supported_features(void __user *arg)
4626{
4627	static const struct btrfs_ioctl_feature_flags features[3] = {
4628		INIT_FEATURE_FLAGS(SUPP),
4629		INIT_FEATURE_FLAGS(SAFE_SET),
4630		INIT_FEATURE_FLAGS(SAFE_CLEAR)
4631	};
4632
4633	if (copy_to_user(arg, &features, sizeof(features)))
4634		return -EFAULT;
4635
4636	return 0;
4637}
4638
4639static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
4640					void __user *arg)
4641{
 
 
4642	struct btrfs_super_block *super_block = fs_info->super_copy;
4643	struct btrfs_ioctl_feature_flags features;
4644
4645	features.compat_flags = btrfs_super_compat_flags(super_block);
4646	features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4647	features.incompat_flags = btrfs_super_incompat_flags(super_block);
4648
4649	if (copy_to_user(arg, &features, sizeof(features)))
4650		return -EFAULT;
4651
4652	return 0;
4653}
4654
4655static int check_feature_bits(struct btrfs_fs_info *fs_info,
4656			      enum btrfs_feature_set set,
4657			      u64 change_mask, u64 flags, u64 supported_flags,
4658			      u64 safe_set, u64 safe_clear)
4659{
4660	const char *type = btrfs_feature_set_name(set);
4661	char *names;
4662	u64 disallowed, unsupported;
4663	u64 set_mask = flags & change_mask;
4664	u64 clear_mask = ~flags & change_mask;
4665
4666	unsupported = set_mask & ~supported_flags;
4667	if (unsupported) {
4668		names = btrfs_printable_features(set, unsupported);
4669		if (names) {
4670			btrfs_warn(fs_info,
4671				   "this kernel does not support the %s feature bit%s",
4672				   names, strchr(names, ',') ? "s" : "");
4673			kfree(names);
4674		} else
4675			btrfs_warn(fs_info,
4676				   "this kernel does not support %s bits 0x%llx",
4677				   type, unsupported);
4678		return -EOPNOTSUPP;
4679	}
4680
4681	disallowed = set_mask & ~safe_set;
4682	if (disallowed) {
4683		names = btrfs_printable_features(set, disallowed);
4684		if (names) {
4685			btrfs_warn(fs_info,
4686				   "can't set the %s feature bit%s while mounted",
4687				   names, strchr(names, ',') ? "s" : "");
4688			kfree(names);
4689		} else
4690			btrfs_warn(fs_info,
4691				   "can't set %s bits 0x%llx while mounted",
4692				   type, disallowed);
4693		return -EPERM;
4694	}
4695
4696	disallowed = clear_mask & ~safe_clear;
4697	if (disallowed) {
4698		names = btrfs_printable_features(set, disallowed);
4699		if (names) {
4700			btrfs_warn(fs_info,
4701				   "can't clear the %s feature bit%s while mounted",
4702				   names, strchr(names, ',') ? "s" : "");
4703			kfree(names);
4704		} else
4705			btrfs_warn(fs_info,
4706				   "can't clear %s bits 0x%llx while mounted",
4707				   type, disallowed);
4708		return -EPERM;
4709	}
4710
4711	return 0;
4712}
4713
4714#define check_feature(fs_info, change_mask, flags, mask_base)	\
4715check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags,	\
4716		   BTRFS_FEATURE_ ## mask_base ## _SUPP,	\
4717		   BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,	\
4718		   BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4719
4720static int btrfs_ioctl_set_features(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_ioctl_feature_flags flags[2];
4727	struct btrfs_trans_handle *trans;
4728	u64 newflags;
4729	int ret;
4730
4731	if (!capable(CAP_SYS_ADMIN))
4732		return -EPERM;
4733
4734	if (copy_from_user(flags, arg, sizeof(flags)))
4735		return -EFAULT;
4736
4737	/* Nothing to do */
4738	if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4739	    !flags[0].incompat_flags)
4740		return 0;
4741
4742	ret = check_feature(fs_info, flags[0].compat_flags,
4743			    flags[1].compat_flags, COMPAT);
4744	if (ret)
4745		return ret;
4746
4747	ret = check_feature(fs_info, flags[0].compat_ro_flags,
4748			    flags[1].compat_ro_flags, COMPAT_RO);
4749	if (ret)
4750		return ret;
4751
4752	ret = check_feature(fs_info, flags[0].incompat_flags,
4753			    flags[1].incompat_flags, INCOMPAT);
4754	if (ret)
4755		return ret;
4756
4757	ret = mnt_want_write_file(file);
4758	if (ret)
4759		return ret;
4760
4761	trans = btrfs_start_transaction(root, 0);
4762	if (IS_ERR(trans)) {
4763		ret = PTR_ERR(trans);
4764		goto out_drop_write;
4765	}
4766
4767	spin_lock(&fs_info->super_lock);
4768	newflags = btrfs_super_compat_flags(super_block);
4769	newflags |= flags[0].compat_flags & flags[1].compat_flags;
4770	newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4771	btrfs_set_super_compat_flags(super_block, newflags);
4772
4773	newflags = btrfs_super_compat_ro_flags(super_block);
4774	newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4775	newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4776	btrfs_set_super_compat_ro_flags(super_block, newflags);
4777
4778	newflags = btrfs_super_incompat_flags(super_block);
4779	newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4780	newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4781	btrfs_set_super_incompat_flags(super_block, newflags);
4782	spin_unlock(&fs_info->super_lock);
4783
4784	ret = btrfs_commit_transaction(trans);
4785out_drop_write:
4786	mnt_drop_write_file(file);
4787
4788	return ret;
4789}
4790
4791static int _btrfs_ioctl_send(struct file *file, void __user *argp, bool compat)
4792{
4793	struct btrfs_ioctl_send_args *arg;
4794	int ret;
4795
4796	if (compat) {
4797#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4798		struct btrfs_ioctl_send_args_32 args32;
4799
4800		ret = copy_from_user(&args32, argp, sizeof(args32));
4801		if (ret)
4802			return -EFAULT;
4803		arg = kzalloc(sizeof(*arg), GFP_KERNEL);
4804		if (!arg)
4805			return -ENOMEM;
4806		arg->send_fd = args32.send_fd;
4807		arg->clone_sources_count = args32.clone_sources_count;
4808		arg->clone_sources = compat_ptr(args32.clone_sources);
4809		arg->parent_root = args32.parent_root;
4810		arg->flags = args32.flags;
4811		memcpy(arg->reserved, args32.reserved,
4812		       sizeof(args32.reserved));
4813#else
4814		return -ENOTTY;
4815#endif
4816	} else {
4817		arg = memdup_user(argp, sizeof(*arg));
4818		if (IS_ERR(arg))
4819			return PTR_ERR(arg);
4820	}
4821	ret = btrfs_ioctl_send(file, arg);
4822	kfree(arg);
4823	return ret;
4824}
4825
4826long btrfs_ioctl(struct file *file, unsigned int
4827		cmd, unsigned long arg)
4828{
4829	struct inode *inode = file_inode(file);
4830	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4831	struct btrfs_root *root = BTRFS_I(inode)->root;
4832	void __user *argp = (void __user *)arg;
4833
4834	switch (cmd) {
4835	case FS_IOC_GETFLAGS:
4836		return btrfs_ioctl_getflags(file, argp);
4837	case FS_IOC_SETFLAGS:
4838		return btrfs_ioctl_setflags(file, argp);
4839	case FS_IOC_GETVERSION:
4840		return btrfs_ioctl_getversion(file, argp);
4841	case FS_IOC_GETFSLABEL:
4842		return btrfs_ioctl_get_fslabel(fs_info, argp);
4843	case FS_IOC_SETFSLABEL:
4844		return btrfs_ioctl_set_fslabel(file, argp);
4845	case FITRIM:
4846		return btrfs_ioctl_fitrim(fs_info, argp);
4847	case BTRFS_IOC_SNAP_CREATE:
4848		return btrfs_ioctl_snap_create(file, argp, 0);
4849	case BTRFS_IOC_SNAP_CREATE_V2:
4850		return btrfs_ioctl_snap_create_v2(file, argp, 0);
4851	case BTRFS_IOC_SUBVOL_CREATE:
4852		return btrfs_ioctl_snap_create(file, argp, 1);
4853	case BTRFS_IOC_SUBVOL_CREATE_V2:
4854		return btrfs_ioctl_snap_create_v2(file, argp, 1);
4855	case BTRFS_IOC_SNAP_DESTROY:
4856		return btrfs_ioctl_snap_destroy(file, argp, false);
4857	case BTRFS_IOC_SNAP_DESTROY_V2:
4858		return btrfs_ioctl_snap_destroy(file, argp, true);
4859	case BTRFS_IOC_SUBVOL_GETFLAGS:
4860		return btrfs_ioctl_subvol_getflags(file, argp);
4861	case BTRFS_IOC_SUBVOL_SETFLAGS:
4862		return btrfs_ioctl_subvol_setflags(file, argp);
4863	case BTRFS_IOC_DEFAULT_SUBVOL:
4864		return btrfs_ioctl_default_subvol(file, argp);
4865	case BTRFS_IOC_DEFRAG:
4866		return btrfs_ioctl_defrag(file, NULL);
4867	case BTRFS_IOC_DEFRAG_RANGE:
4868		return btrfs_ioctl_defrag(file, argp);
4869	case BTRFS_IOC_RESIZE:
4870		return btrfs_ioctl_resize(file, argp);
4871	case BTRFS_IOC_ADD_DEV:
4872		return btrfs_ioctl_add_dev(fs_info, argp);
4873	case BTRFS_IOC_RM_DEV:
4874		return btrfs_ioctl_rm_dev(file, argp);
4875	case BTRFS_IOC_RM_DEV_V2:
4876		return btrfs_ioctl_rm_dev_v2(file, argp);
4877	case BTRFS_IOC_FS_INFO:
4878		return btrfs_ioctl_fs_info(fs_info, argp);
4879	case BTRFS_IOC_DEV_INFO:
4880		return btrfs_ioctl_dev_info(fs_info, argp);
4881	case BTRFS_IOC_BALANCE:
4882		return btrfs_ioctl_balance(file, NULL);
 
 
 
 
4883	case BTRFS_IOC_TREE_SEARCH:
4884		return btrfs_ioctl_tree_search(file, argp);
4885	case BTRFS_IOC_TREE_SEARCH_V2:
4886		return btrfs_ioctl_tree_search_v2(file, argp);
4887	case BTRFS_IOC_INO_LOOKUP:
4888		return btrfs_ioctl_ino_lookup(file, argp);
4889	case BTRFS_IOC_INO_PATHS:
4890		return btrfs_ioctl_ino_to_path(root, argp);
4891	case BTRFS_IOC_LOGICAL_INO:
4892		return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
4893	case BTRFS_IOC_LOGICAL_INO_V2:
4894		return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
4895	case BTRFS_IOC_SPACE_INFO:
4896		return btrfs_ioctl_space_info(fs_info, argp);
4897	case BTRFS_IOC_SYNC: {
4898		int ret;
4899
4900		ret = btrfs_start_delalloc_roots(fs_info, -1);
4901		if (ret)
4902			return ret;
4903		ret = btrfs_sync_fs(inode->i_sb, 1);
4904		/*
4905		 * The transaction thread may want to do more work,
4906		 * namely it pokes the cleaner kthread that will start
4907		 * processing uncleaned subvols.
4908		 */
4909		wake_up_process(fs_info->transaction_kthread);
4910		return ret;
4911	}
4912	case BTRFS_IOC_START_SYNC:
4913		return btrfs_ioctl_start_sync(root, argp);
4914	case BTRFS_IOC_WAIT_SYNC:
4915		return btrfs_ioctl_wait_sync(fs_info, argp);
4916	case BTRFS_IOC_SCRUB:
4917		return btrfs_ioctl_scrub(file, argp);
4918	case BTRFS_IOC_SCRUB_CANCEL:
4919		return btrfs_ioctl_scrub_cancel(fs_info);
4920	case BTRFS_IOC_SCRUB_PROGRESS:
4921		return btrfs_ioctl_scrub_progress(fs_info, argp);
4922	case BTRFS_IOC_BALANCE_V2:
4923		return btrfs_ioctl_balance(file, argp);
4924	case BTRFS_IOC_BALANCE_CTL:
4925		return btrfs_ioctl_balance_ctl(fs_info, arg);
4926	case BTRFS_IOC_BALANCE_PROGRESS:
4927		return btrfs_ioctl_balance_progress(fs_info, argp);
4928	case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4929		return btrfs_ioctl_set_received_subvol(file, argp);
4930#ifdef CONFIG_64BIT
4931	case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4932		return btrfs_ioctl_set_received_subvol_32(file, argp);
4933#endif
4934	case BTRFS_IOC_SEND:
4935		return _btrfs_ioctl_send(file, argp, false);
4936#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4937	case BTRFS_IOC_SEND_32:
4938		return _btrfs_ioctl_send(file, argp, true);
4939#endif
4940	case BTRFS_IOC_GET_DEV_STATS:
4941		return btrfs_ioctl_get_dev_stats(fs_info, argp);
4942	case BTRFS_IOC_QUOTA_CTL:
4943		return btrfs_ioctl_quota_ctl(file, argp);
4944	case BTRFS_IOC_QGROUP_ASSIGN:
4945		return btrfs_ioctl_qgroup_assign(file, argp);
4946	case BTRFS_IOC_QGROUP_CREATE:
4947		return btrfs_ioctl_qgroup_create(file, argp);
4948	case BTRFS_IOC_QGROUP_LIMIT:
4949		return btrfs_ioctl_qgroup_limit(file, argp);
4950	case BTRFS_IOC_QUOTA_RESCAN:
4951		return btrfs_ioctl_quota_rescan(file, argp);
4952	case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4953		return btrfs_ioctl_quota_rescan_status(fs_info, argp);
4954	case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4955		return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
4956	case BTRFS_IOC_DEV_REPLACE:
4957		return btrfs_ioctl_dev_replace(fs_info, argp);
 
 
 
 
4958	case BTRFS_IOC_GET_SUPPORTED_FEATURES:
4959		return btrfs_ioctl_get_supported_features(argp);
4960	case BTRFS_IOC_GET_FEATURES:
4961		return btrfs_ioctl_get_features(fs_info, argp);
4962	case BTRFS_IOC_SET_FEATURES:
4963		return btrfs_ioctl_set_features(file, argp);
4964	case FS_IOC_FSGETXATTR:
4965		return btrfs_ioctl_fsgetxattr(file, argp);
4966	case FS_IOC_FSSETXATTR:
4967		return btrfs_ioctl_fssetxattr(file, argp);
4968	case BTRFS_IOC_GET_SUBVOL_INFO:
4969		return btrfs_ioctl_get_subvol_info(file, argp);
4970	case BTRFS_IOC_GET_SUBVOL_ROOTREF:
4971		return btrfs_ioctl_get_subvol_rootref(file, argp);
4972	case BTRFS_IOC_INO_LOOKUP_USER:
4973		return btrfs_ioctl_ino_lookup_user(file, argp);
4974	}
4975
4976	return -ENOTTY;
4977}
4978
4979#ifdef CONFIG_COMPAT
4980long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
4981{
4982	/*
4983	 * These all access 32-bit values anyway so no further
4984	 * handling is necessary.
4985	 */
4986	switch (cmd) {
4987	case FS_IOC32_GETFLAGS:
4988		cmd = FS_IOC_GETFLAGS;
4989		break;
4990	case FS_IOC32_SETFLAGS:
4991		cmd = FS_IOC_SETFLAGS;
4992		break;
4993	case FS_IOC32_GETVERSION:
4994		cmd = FS_IOC_GETVERSION;
4995		break;
4996	}
4997
4998	return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
4999}
5000#endif