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v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Copyright (C) 2007 Oracle.  All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   4 */
   5
   6#include <linux/kernel.h>
   7#include <linux/bio.h>
 
   8#include <linux/file.h>
   9#include <linux/fs.h>
  10#include <linux/fsnotify.h>
  11#include <linux/pagemap.h>
  12#include <linux/highmem.h>
  13#include <linux/time.h>
 
  14#include <linux/string.h>
  15#include <linux/backing-dev.h>
  16#include <linux/mount.h>
 
  17#include <linux/namei.h>
 
  18#include <linux/writeback.h>
 
  19#include <linux/compat.h>
 
  20#include <linux/security.h>
  21#include <linux/xattr.h>
  22#include <linux/mm.h>
  23#include <linux/slab.h>
  24#include <linux/blkdev.h>
  25#include <linux/uuid.h>
  26#include <linux/btrfs.h>
  27#include <linux/uaccess.h>
  28#include <linux/iversion.h>
  29#include <linux/fileattr.h>
  30#include <linux/fsverity.h>
  31#include <linux/sched/xacct.h>
  32#include "ctree.h"
  33#include "disk-io.h"
  34#include "export.h"
  35#include "transaction.h"
  36#include "btrfs_inode.h"
 
  37#include "print-tree.h"
  38#include "volumes.h"
  39#include "locking.h"
 
  40#include "backref.h"
  41#include "rcu-string.h"
  42#include "send.h"
  43#include "dev-replace.h"
  44#include "props.h"
  45#include "sysfs.h"
  46#include "qgroup.h"
  47#include "tree-log.h"
  48#include "compression.h"
  49#include "space-info.h"
  50#include "delalloc-space.h"
  51#include "block-group.h"
  52#include "subpage.h"
  53#include "fs.h"
  54#include "accessors.h"
  55#include "extent-tree.h"
  56#include "root-tree.h"
  57#include "defrag.h"
  58#include "dir-item.h"
  59#include "uuid-tree.h"
  60#include "ioctl.h"
  61#include "file.h"
  62#include "scrub.h"
  63#include "super.h"
  64
  65#ifdef CONFIG_64BIT
  66/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
  67 * structures are incorrect, as the timespec structure from userspace
  68 * is 4 bytes too small. We define these alternatives here to teach
  69 * the kernel about the 32-bit struct packing.
  70 */
  71struct btrfs_ioctl_timespec_32 {
  72	__u64 sec;
  73	__u32 nsec;
  74} __attribute__ ((__packed__));
  75
  76struct btrfs_ioctl_received_subvol_args_32 {
  77	char	uuid[BTRFS_UUID_SIZE];	/* in */
  78	__u64	stransid;		/* in */
  79	__u64	rtransid;		/* out */
  80	struct btrfs_ioctl_timespec_32 stime; /* in */
  81	struct btrfs_ioctl_timespec_32 rtime; /* out */
  82	__u64	flags;			/* in */
  83	__u64	reserved[16];		/* in */
  84} __attribute__ ((__packed__));
  85
  86#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
  87				struct btrfs_ioctl_received_subvol_args_32)
  88#endif
  89
  90#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
  91struct btrfs_ioctl_send_args_32 {
  92	__s64 send_fd;			/* in */
  93	__u64 clone_sources_count;	/* in */
  94	compat_uptr_t clone_sources;	/* in */
  95	__u64 parent_root;		/* in */
  96	__u64 flags;			/* in */
  97	__u32 version;			/* in */
  98	__u8  reserved[28];		/* in */
  99} __attribute__ ((__packed__));
 100
 101#define BTRFS_IOC_SEND_32 _IOW(BTRFS_IOCTL_MAGIC, 38, \
 102			       struct btrfs_ioctl_send_args_32)
 103
 104struct btrfs_ioctl_encoded_io_args_32 {
 105	compat_uptr_t iov;
 106	compat_ulong_t iovcnt;
 107	__s64 offset;
 108	__u64 flags;
 109	__u64 len;
 110	__u64 unencoded_len;
 111	__u64 unencoded_offset;
 112	__u32 compression;
 113	__u32 encryption;
 114	__u8 reserved[64];
 115};
 116
 117#define BTRFS_IOC_ENCODED_READ_32 _IOR(BTRFS_IOCTL_MAGIC, 64, \
 118				       struct btrfs_ioctl_encoded_io_args_32)
 119#define BTRFS_IOC_ENCODED_WRITE_32 _IOW(BTRFS_IOCTL_MAGIC, 64, \
 120					struct btrfs_ioctl_encoded_io_args_32)
 121#endif
 122
 123/* Mask out flags that are inappropriate for the given type of inode. */
 124static unsigned int btrfs_mask_fsflags_for_type(struct inode *inode,
 125		unsigned int flags)
 126{
 127	if (S_ISDIR(inode->i_mode))
 128		return flags;
 129	else if (S_ISREG(inode->i_mode))
 130		return flags & ~FS_DIRSYNC_FL;
 131	else
 132		return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
 133}
 134
 135/*
 136 * Export internal inode flags to the format expected by the FS_IOC_GETFLAGS
 137 * ioctl.
 138 */
 139static unsigned int btrfs_inode_flags_to_fsflags(struct btrfs_inode *binode)
 140{
 141	unsigned int iflags = 0;
 142	u32 flags = binode->flags;
 143	u32 ro_flags = binode->ro_flags;
 144
 145	if (flags & BTRFS_INODE_SYNC)
 146		iflags |= FS_SYNC_FL;
 147	if (flags & BTRFS_INODE_IMMUTABLE)
 148		iflags |= FS_IMMUTABLE_FL;
 149	if (flags & BTRFS_INODE_APPEND)
 150		iflags |= FS_APPEND_FL;
 151	if (flags & BTRFS_INODE_NODUMP)
 152		iflags |= FS_NODUMP_FL;
 153	if (flags & BTRFS_INODE_NOATIME)
 154		iflags |= FS_NOATIME_FL;
 155	if (flags & BTRFS_INODE_DIRSYNC)
 156		iflags |= FS_DIRSYNC_FL;
 157	if (flags & BTRFS_INODE_NODATACOW)
 158		iflags |= FS_NOCOW_FL;
 159	if (ro_flags & BTRFS_INODE_RO_VERITY)
 160		iflags |= FS_VERITY_FL;
 161
 162	if (flags & BTRFS_INODE_NOCOMPRESS)
 163		iflags |= FS_NOCOMP_FL;
 164	else if (flags & BTRFS_INODE_COMPRESS)
 165		iflags |= FS_COMPR_FL;
 
 
 166
 167	return iflags;
 168}
 169
 170/*
 171 * Update inode->i_flags based on the btrfs internal flags.
 172 */
 173void btrfs_sync_inode_flags_to_i_flags(struct inode *inode)
 174{
 175	struct btrfs_inode *binode = BTRFS_I(inode);
 176	unsigned int new_fl = 0;
 177
 178	if (binode->flags & BTRFS_INODE_SYNC)
 179		new_fl |= S_SYNC;
 180	if (binode->flags & BTRFS_INODE_IMMUTABLE)
 181		new_fl |= S_IMMUTABLE;
 182	if (binode->flags & BTRFS_INODE_APPEND)
 183		new_fl |= S_APPEND;
 184	if (binode->flags & BTRFS_INODE_NOATIME)
 185		new_fl |= S_NOATIME;
 186	if (binode->flags & BTRFS_INODE_DIRSYNC)
 187		new_fl |= S_DIRSYNC;
 188	if (binode->ro_flags & BTRFS_INODE_RO_VERITY)
 189		new_fl |= S_VERITY;
 190
 191	set_mask_bits(&inode->i_flags,
 192		      S_SYNC | S_APPEND | S_IMMUTABLE | S_NOATIME | S_DIRSYNC |
 193		      S_VERITY, new_fl);
 194}
 195
 196/*
 197 * Check if @flags are a supported and valid set of FS_*_FL flags and that
 198 * the old and new flags are not conflicting
 
 199 */
 200static int check_fsflags(unsigned int old_flags, unsigned int flags)
 201{
 202	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 203		      FS_NOATIME_FL | FS_NODUMP_FL | \
 204		      FS_SYNC_FL | FS_DIRSYNC_FL | \
 205		      FS_NOCOMP_FL | FS_COMPR_FL |
 206		      FS_NOCOW_FL))
 207		return -EOPNOTSUPP;
 208
 209	/* COMPR and NOCOMP on new/old are valid */
 210	if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 211		return -EINVAL;
 212
 213	if ((flags & FS_COMPR_FL) && (flags & FS_NOCOW_FL))
 214		return -EINVAL;
 215
 216	/* NOCOW and compression options are mutually exclusive */
 217	if ((old_flags & FS_NOCOW_FL) && (flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
 218		return -EINVAL;
 219	if ((flags & FS_NOCOW_FL) && (old_flags & (FS_COMPR_FL | FS_NOCOMP_FL)))
 220		return -EINVAL;
 
 
 221
 222	return 0;
 
 
 
 223}
 224
 225static int check_fsflags_compatible(struct btrfs_fs_info *fs_info,
 226				    unsigned int flags)
 227{
 228	if (btrfs_is_zoned(fs_info) && (flags & FS_NOCOW_FL))
 229		return -EPERM;
 230
 
 
 231	return 0;
 232}
 233
 234/*
 235 * Set flags/xflags from the internal inode flags. The remaining items of
 236 * fsxattr are zeroed.
 237 */
 238int btrfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
 239{
 240	struct btrfs_inode *binode = BTRFS_I(d_inode(dentry));
 
 
 
 
 
 
 
 
 241
 242	fileattr_fill_flags(fa, btrfs_inode_flags_to_fsflags(binode));
 243	return 0;
 244}
 245
 246int btrfs_fileattr_set(struct user_namespace *mnt_userns,
 247		       struct dentry *dentry, struct fileattr *fa)
 248{
 249	struct inode *inode = d_inode(dentry);
 250	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 251	struct btrfs_inode *binode = BTRFS_I(inode);
 252	struct btrfs_root *root = binode->root;
 253	struct btrfs_trans_handle *trans;
 254	unsigned int fsflags, old_fsflags;
 255	int ret;
 256	const char *comp = NULL;
 257	u32 binode_flags;
 258
 259	if (btrfs_root_readonly(root))
 260		return -EROFS;
 261
 262	if (fileattr_has_fsx(fa))
 263		return -EOPNOTSUPP;
 264
 265	fsflags = btrfs_mask_fsflags_for_type(inode, fa->flags);
 266	old_fsflags = btrfs_inode_flags_to_fsflags(binode);
 267	ret = check_fsflags(old_fsflags, fsflags);
 268	if (ret)
 269		return ret;
 270
 271	ret = check_fsflags_compatible(fs_info, fsflags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 272	if (ret)
 273		return ret;
 274
 275	binode_flags = binode->flags;
 276	if (fsflags & FS_SYNC_FL)
 277		binode_flags |= BTRFS_INODE_SYNC;
 278	else
 279		binode_flags &= ~BTRFS_INODE_SYNC;
 280	if (fsflags & FS_IMMUTABLE_FL)
 281		binode_flags |= BTRFS_INODE_IMMUTABLE;
 282	else
 283		binode_flags &= ~BTRFS_INODE_IMMUTABLE;
 284	if (fsflags & FS_APPEND_FL)
 285		binode_flags |= BTRFS_INODE_APPEND;
 286	else
 287		binode_flags &= ~BTRFS_INODE_APPEND;
 288	if (fsflags & FS_NODUMP_FL)
 289		binode_flags |= BTRFS_INODE_NODUMP;
 290	else
 291		binode_flags &= ~BTRFS_INODE_NODUMP;
 292	if (fsflags & FS_NOATIME_FL)
 293		binode_flags |= BTRFS_INODE_NOATIME;
 294	else
 295		binode_flags &= ~BTRFS_INODE_NOATIME;
 296
 297	/* If coming from FS_IOC_FSSETXATTR then skip unconverted flags */
 298	if (!fa->flags_valid) {
 299		/* 1 item for the inode */
 300		trans = btrfs_start_transaction(root, 1);
 301		if (IS_ERR(trans))
 302			return PTR_ERR(trans);
 303		goto update_flags;
 304	}
 305
 306	if (fsflags & FS_DIRSYNC_FL)
 307		binode_flags |= BTRFS_INODE_DIRSYNC;
 308	else
 309		binode_flags &= ~BTRFS_INODE_DIRSYNC;
 310	if (fsflags & FS_NOCOW_FL) {
 311		if (S_ISREG(inode->i_mode)) {
 312			/*
 313			 * It's safe to turn csums off here, no extents exist.
 314			 * Otherwise we want the flag to reflect the real COW
 315			 * status of the file and will not set it.
 316			 */
 317			if (inode->i_size == 0)
 318				binode_flags |= BTRFS_INODE_NODATACOW |
 319						BTRFS_INODE_NODATASUM;
 320		} else {
 321			binode_flags |= BTRFS_INODE_NODATACOW;
 322		}
 323	} else {
 324		/*
 325		 * Revert back under same assumptions as above
 326		 */
 327		if (S_ISREG(inode->i_mode)) {
 328			if (inode->i_size == 0)
 329				binode_flags &= ~(BTRFS_INODE_NODATACOW |
 330						  BTRFS_INODE_NODATASUM);
 331		} else {
 332			binode_flags &= ~BTRFS_INODE_NODATACOW;
 333		}
 334	}
 335
 336	/*
 337	 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 338	 * flag may be changed automatically if compression code won't make
 339	 * things smaller.
 340	 */
 341	if (fsflags & FS_NOCOMP_FL) {
 342		binode_flags &= ~BTRFS_INODE_COMPRESS;
 343		binode_flags |= BTRFS_INODE_NOCOMPRESS;
 344	} else if (fsflags & FS_COMPR_FL) {
 345
 346		if (IS_SWAPFILE(inode))
 347			return -ETXTBSY;
 348
 349		binode_flags |= BTRFS_INODE_COMPRESS;
 350		binode_flags &= ~BTRFS_INODE_NOCOMPRESS;
 351
 352		comp = btrfs_compress_type2str(fs_info->compress_type);
 353		if (!comp || comp[0] == 0)
 354			comp = btrfs_compress_type2str(BTRFS_COMPRESS_ZLIB);
 355	} else {
 356		binode_flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 357	}
 358
 359	/*
 360	 * 1 for inode item
 361	 * 2 for properties
 362	 */
 363	trans = btrfs_start_transaction(root, 3);
 364	if (IS_ERR(trans))
 365		return PTR_ERR(trans);
 366
 367	if (comp) {
 368		ret = btrfs_set_prop(trans, inode, "btrfs.compression", comp,
 369				     strlen(comp), 0);
 370		if (ret) {
 371			btrfs_abort_transaction(trans, ret);
 372			goto out_end_trans;
 373		}
 374	} else {
 375		ret = btrfs_set_prop(trans, inode, "btrfs.compression", NULL,
 376				     0, 0);
 377		if (ret && ret != -ENODATA) {
 378			btrfs_abort_transaction(trans, ret);
 379			goto out_end_trans;
 380		}
 381	}
 382
 383update_flags:
 384	binode->flags = binode_flags;
 385	btrfs_sync_inode_flags_to_i_flags(inode);
 386	inode_inc_iversion(inode);
 387	inode->i_ctime = current_time(inode);
 388	ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
 389
 390 out_end_trans:
 391	btrfs_end_transaction(trans);
 392	return ret;
 393}
 394
 395/*
 396 * Start exclusive operation @type, return true on success
 397 */
 398bool btrfs_exclop_start(struct btrfs_fs_info *fs_info,
 399			enum btrfs_exclusive_operation type)
 400{
 401	bool ret = false;
 402
 403	spin_lock(&fs_info->super_lock);
 404	if (fs_info->exclusive_operation == BTRFS_EXCLOP_NONE) {
 405		fs_info->exclusive_operation = type;
 406		ret = true;
 
 407	}
 408	spin_unlock(&fs_info->super_lock);
 409
 
 
 
 410	return ret;
 411}
 412
 413/*
 414 * Conditionally allow to enter the exclusive operation in case it's compatible
 415 * with the running one.  This must be paired with btrfs_exclop_start_unlock and
 416 * btrfs_exclop_finish.
 417 *
 418 * Compatibility:
 419 * - the same type is already running
 420 * - when trying to add a device and balance has been paused
 421 * - not BTRFS_EXCLOP_NONE - this is intentionally incompatible and the caller
 422 *   must check the condition first that would allow none -> @type
 423 */
 424bool btrfs_exclop_start_try_lock(struct btrfs_fs_info *fs_info,
 425				 enum btrfs_exclusive_operation type)
 426{
 427	spin_lock(&fs_info->super_lock);
 428	if (fs_info->exclusive_operation == type ||
 429	    (fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED &&
 430	     type == BTRFS_EXCLOP_DEV_ADD))
 431		return true;
 432
 433	spin_unlock(&fs_info->super_lock);
 434	return false;
 435}
 436
 437void btrfs_exclop_start_unlock(struct btrfs_fs_info *fs_info)
 438{
 439	spin_unlock(&fs_info->super_lock);
 440}
 441
 442void btrfs_exclop_finish(struct btrfs_fs_info *fs_info)
 443{
 444	spin_lock(&fs_info->super_lock);
 445	WRITE_ONCE(fs_info->exclusive_operation, BTRFS_EXCLOP_NONE);
 446	spin_unlock(&fs_info->super_lock);
 447	sysfs_notify(&fs_info->fs_devices->fsid_kobj, NULL, "exclusive_operation");
 448}
 449
 450void btrfs_exclop_balance(struct btrfs_fs_info *fs_info,
 451			  enum btrfs_exclusive_operation op)
 452{
 453	switch (op) {
 454	case BTRFS_EXCLOP_BALANCE_PAUSED:
 455		spin_lock(&fs_info->super_lock);
 456		ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE ||
 457		       fs_info->exclusive_operation == BTRFS_EXCLOP_DEV_ADD);
 458		fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE_PAUSED;
 459		spin_unlock(&fs_info->super_lock);
 460		break;
 461	case BTRFS_EXCLOP_BALANCE:
 462		spin_lock(&fs_info->super_lock);
 463		ASSERT(fs_info->exclusive_operation == BTRFS_EXCLOP_BALANCE_PAUSED);
 464		fs_info->exclusive_operation = BTRFS_EXCLOP_BALANCE;
 465		spin_unlock(&fs_info->super_lock);
 466		break;
 467	default:
 468		btrfs_warn(fs_info,
 469			"invalid exclop balance operation %d requested", op);
 470	}
 471}
 472
 473static int btrfs_ioctl_getversion(struct inode *inode, int __user *arg)
 474{
 475	return put_user(inode->i_generation, arg);
 476}
 477
 478static noinline int btrfs_ioctl_fitrim(struct btrfs_fs_info *fs_info,
 479					void __user *arg)
 480{
 
 481	struct btrfs_device *device;
 
 482	struct fstrim_range range;
 483	u64 minlen = ULLONG_MAX;
 484	u64 num_devices = 0;
 
 485	int ret;
 486
 487	if (!capable(CAP_SYS_ADMIN))
 488		return -EPERM;
 489
 490	/*
 491	 * btrfs_trim_block_group() depends on space cache, which is not
 492	 * available in zoned filesystem. So, disallow fitrim on a zoned
 493	 * filesystem for now.
 494	 */
 495	if (btrfs_is_zoned(fs_info))
 496		return -EOPNOTSUPP;
 497
 498	/*
 499	 * If the fs is mounted with nologreplay, which requires it to be
 500	 * mounted in RO mode as well, we can not allow discard on free space
 501	 * inside block groups, because log trees refer to extents that are not
 502	 * pinned in a block group's free space cache (pinning the extents is
 503	 * precisely the first phase of replaying a log tree).
 504	 */
 505	if (btrfs_test_opt(fs_info, NOLOGREPLAY))
 506		return -EROFS;
 507
 508	rcu_read_lock();
 509	list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 510				dev_list) {
 511		if (!device->bdev || !bdev_max_discard_sectors(device->bdev))
 512			continue;
 513		num_devices++;
 514		minlen = min_t(u64, bdev_discard_granularity(device->bdev),
 515				    minlen);
 
 
 
 516	}
 517	rcu_read_unlock();
 518
 519	if (!num_devices)
 520		return -EOPNOTSUPP;
 521	if (copy_from_user(&range, arg, sizeof(range)))
 522		return -EFAULT;
 523
 524	/*
 525	 * NOTE: Don't truncate the range using super->total_bytes.  Bytenr of
 526	 * block group is in the logical address space, which can be any
 527	 * sectorsize aligned bytenr in  the range [0, U64_MAX].
 528	 */
 529	if (range.len < fs_info->sb->s_blocksize)
 530		return -EINVAL;
 531
 
 532	range.minlen = max(range.minlen, minlen);
 533	ret = btrfs_trim_fs(fs_info, &range);
 534	if (ret < 0)
 535		return ret;
 536
 537	if (copy_to_user(arg, &range, sizeof(range)))
 538		return -EFAULT;
 539
 540	return 0;
 541}
 542
 543int __pure btrfs_is_empty_uuid(u8 *uuid)
 544{
 545	int i;
 546
 547	for (i = 0; i < BTRFS_UUID_SIZE; i++) {
 548		if (uuid[i])
 549			return 0;
 550	}
 551	return 1;
 552}
 553
 554/*
 555 * Calculate the number of transaction items to reserve for creating a subvolume
 556 * or snapshot, not including the inode, directory entries, or parent directory.
 557 */
 558static unsigned int create_subvol_num_items(struct btrfs_qgroup_inherit *inherit)
 559{
 560	/*
 561	 * 1 to add root block
 562	 * 1 to add root item
 563	 * 1 to add root ref
 564	 * 1 to add root backref
 565	 * 1 to add UUID item
 566	 * 1 to add qgroup info
 567	 * 1 to add qgroup limit
 568	 *
 569	 * Ideally the last two would only be accounted if qgroups are enabled,
 570	 * but that can change between now and the time we would insert them.
 571	 */
 572	unsigned int num_items = 7;
 573
 574	if (inherit) {
 575		/* 2 to add qgroup relations for each inherited qgroup */
 576		num_items += 2 * inherit->num_qgroups;
 577	}
 578	return num_items;
 579}
 580
 581static noinline int create_subvol(struct user_namespace *mnt_userns,
 582				  struct inode *dir, struct dentry *dentry,
 583				  struct btrfs_qgroup_inherit *inherit)
 584{
 585	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 586	struct btrfs_trans_handle *trans;
 587	struct btrfs_key key;
 588	struct btrfs_root_item *root_item;
 589	struct btrfs_inode_item *inode_item;
 590	struct extent_buffer *leaf;
 591	struct btrfs_root *root = BTRFS_I(dir)->root;
 592	struct btrfs_root *new_root;
 593	struct btrfs_block_rsv block_rsv;
 594	struct timespec64 cur_time = current_time(dir);
 595	struct btrfs_new_inode_args new_inode_args = {
 596		.dir = dir,
 597		.dentry = dentry,
 598		.subvol = true,
 599	};
 600	unsigned int trans_num_items;
 601	int ret;
 602	dev_t anon_dev;
 603	u64 objectid;
 
 
 604
 605	root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
 606	if (!root_item)
 607		return -ENOMEM;
 608
 609	ret = btrfs_get_free_objectid(fs_info->tree_root, &objectid);
 610	if (ret)
 611		goto out_root_item;
 
 
 612
 613	/*
 614	 * Don't create subvolume whose level is not zero. Or qgroup will be
 615	 * screwed up since it assumes subvolume qgroup's level to be 0.
 
 
 616	 */
 617	if (btrfs_qgroup_level(objectid)) {
 618		ret = -ENOSPC;
 619		goto out_root_item;
 620	}
 621
 622	ret = get_anon_bdev(&anon_dev);
 623	if (ret < 0)
 624		goto out_root_item;
 625
 626	new_inode_args.inode = btrfs_new_subvol_inode(mnt_userns, dir);
 627	if (!new_inode_args.inode) {
 628		ret = -ENOMEM;
 629		goto out_anon_dev;
 630	}
 631	ret = btrfs_new_inode_prepare(&new_inode_args, &trans_num_items);
 632	if (ret)
 633		goto out_inode;
 634	trans_num_items += create_subvol_num_items(inherit);
 635
 636	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
 637	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
 638					       trans_num_items, false);
 639	if (ret)
 640		goto out_new_inode_args;
 641
 642	trans = btrfs_start_transaction(root, 0);
 643	if (IS_ERR(trans)) {
 644		ret = PTR_ERR(trans);
 645		btrfs_subvolume_release_metadata(root, &block_rsv);
 646		goto out_new_inode_args;
 647	}
 648	trans->block_rsv = &block_rsv;
 649	trans->bytes_reserved = block_rsv.size;
 650
 651	ret = btrfs_qgroup_inherit(trans, 0, objectid, inherit);
 652	if (ret)
 653		goto out;
 654
 655	leaf = btrfs_alloc_tree_block(trans, root, 0, objectid, NULL, 0, 0, 0,
 656				      BTRFS_NESTING_NORMAL);
 657	if (IS_ERR(leaf)) {
 658		ret = PTR_ERR(leaf);
 659		goto out;
 660	}
 661
 
 
 
 
 
 
 
 
 
 
 
 
 662	btrfs_mark_buffer_dirty(leaf);
 663
 664	inode_item = &root_item->inode;
 665	btrfs_set_stack_inode_generation(inode_item, 1);
 666	btrfs_set_stack_inode_size(inode_item, 3);
 667	btrfs_set_stack_inode_nlink(inode_item, 1);
 668	btrfs_set_stack_inode_nbytes(inode_item,
 669				     fs_info->nodesize);
 670	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
 671
 672	btrfs_set_root_flags(root_item, 0);
 673	btrfs_set_root_limit(root_item, 0);
 674	btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
 675
 676	btrfs_set_root_bytenr(root_item, leaf->start);
 677	btrfs_set_root_generation(root_item, trans->transid);
 678	btrfs_set_root_level(root_item, 0);
 679	btrfs_set_root_refs(root_item, 1);
 680	btrfs_set_root_used(root_item, leaf->len);
 681	btrfs_set_root_last_snapshot(root_item, 0);
 682
 683	btrfs_set_root_generation_v2(root_item,
 684			btrfs_root_generation(root_item));
 685	generate_random_guid(root_item->uuid);
 686	btrfs_set_stack_timespec_sec(&root_item->otime, cur_time.tv_sec);
 687	btrfs_set_stack_timespec_nsec(&root_item->otime, cur_time.tv_nsec);
 688	root_item->ctime = root_item->otime;
 689	btrfs_set_root_ctransid(root_item, trans->transid);
 690	btrfs_set_root_otransid(root_item, trans->transid);
 691
 692	btrfs_tree_unlock(leaf);
 
 
 693
 694	btrfs_set_root_dirid(root_item, BTRFS_FIRST_FREE_OBJECTID);
 695
 696	key.objectid = objectid;
 697	key.offset = 0;
 698	key.type = BTRFS_ROOT_ITEM_KEY;
 699	ret = btrfs_insert_root(trans, fs_info->tree_root, &key,
 700				root_item);
 701	if (ret) {
 702		/*
 703		 * Since we don't abort the transaction in this case, free the
 704		 * tree block so that we don't leak space and leave the
 705		 * filesystem in an inconsistent state (an extent item in the
 706		 * extent tree with a backreference for a root that does not
 707		 * exists).
 708		 */
 709		btrfs_tree_lock(leaf);
 710		btrfs_clean_tree_block(leaf);
 711		btrfs_tree_unlock(leaf);
 712		btrfs_free_tree_block(trans, objectid, leaf, 0, 1);
 713		free_extent_buffer(leaf);
 714		goto out;
 715	}
 716
 717	free_extent_buffer(leaf);
 718	leaf = NULL;
 719
 720	new_root = btrfs_get_new_fs_root(fs_info, objectid, anon_dev);
 
 721	if (IS_ERR(new_root)) {
 
 722		ret = PTR_ERR(new_root);
 723		btrfs_abort_transaction(trans, ret);
 724		goto out;
 725	}
 726	/* anon_dev is owned by new_root now. */
 727	anon_dev = 0;
 728	BTRFS_I(new_inode_args.inode)->root = new_root;
 729	/* ... and new_root is owned by new_inode_args.inode now. */
 730
 731	ret = btrfs_record_root_in_trans(trans, new_root);
 
 
 732	if (ret) {
 733		btrfs_abort_transaction(trans, ret);
 734		goto out;
 
 735	}
 736
 737	ret = btrfs_uuid_tree_add(trans, root_item->uuid,
 738				  BTRFS_UUID_KEY_SUBVOL, objectid);
 
 
 739	if (ret) {
 740		btrfs_abort_transaction(trans, ret);
 741		goto out;
 742	}
 743
 744	ret = btrfs_create_new_inode(trans, &new_inode_args);
 
 
 745	if (ret) {
 746		btrfs_abort_transaction(trans, ret);
 747		goto out;
 748	}
 749
 750	d_instantiate_new(dentry, new_inode_args.inode);
 751	new_inode_args.inode = NULL;
 
 752
 753out:
 754	trans->block_rsv = NULL;
 755	trans->bytes_reserved = 0;
 756	btrfs_subvolume_release_metadata(root, &block_rsv);
 757
 758	if (ret)
 759		btrfs_end_transaction(trans);
 760	else
 761		ret = btrfs_commit_transaction(trans);
 762out_new_inode_args:
 763	btrfs_new_inode_args_destroy(&new_inode_args);
 764out_inode:
 765	iput(new_inode_args.inode);
 766out_anon_dev:
 767	if (anon_dev)
 768		free_anon_bdev(anon_dev);
 769out_root_item:
 770	kfree(root_item);
 771	return ret;
 772}
 773
 774static int create_snapshot(struct btrfs_root *root, struct inode *dir,
 775			   struct dentry *dentry, bool readonly,
 776			   struct btrfs_qgroup_inherit *inherit)
 777{
 778	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 779	struct inode *inode;
 780	struct btrfs_pending_snapshot *pending_snapshot;
 781	unsigned int trans_num_items;
 782	struct btrfs_trans_handle *trans;
 783	int ret;
 784
 785	/* We do not support snapshotting right now. */
 786	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
 787		btrfs_warn(fs_info,
 788			   "extent tree v2 doesn't support snapshotting yet");
 789		return -EOPNOTSUPP;
 790	}
 791
 792	if (!test_bit(BTRFS_ROOT_SHAREABLE, &root->state))
 793		return -EINVAL;
 794
 795	if (atomic_read(&root->nr_swapfiles)) {
 796		btrfs_warn(fs_info,
 797			   "cannot snapshot subvolume with active swapfile");
 798		return -ETXTBSY;
 799	}
 800
 801	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_KERNEL);
 802	if (!pending_snapshot)
 803		return -ENOMEM;
 804
 805	ret = get_anon_bdev(&pending_snapshot->anon_dev);
 806	if (ret < 0)
 807		goto free_pending;
 808	pending_snapshot->root_item = kzalloc(sizeof(struct btrfs_root_item),
 809			GFP_KERNEL);
 810	pending_snapshot->path = btrfs_alloc_path();
 811	if (!pending_snapshot->root_item || !pending_snapshot->path) {
 812		ret = -ENOMEM;
 813		goto free_pending;
 814	}
 815
 816	btrfs_init_block_rsv(&pending_snapshot->block_rsv,
 817			     BTRFS_BLOCK_RSV_TEMP);
 818	/*
 819	 * 1 to add dir item
 820	 * 1 to add dir index
 821	 * 1 to update parent inode item
 822	 */
 823	trans_num_items = create_subvol_num_items(inherit) + 3;
 824	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 825					       &pending_snapshot->block_rsv,
 826					       trans_num_items, false);
 827	if (ret)
 828		goto free_pending;
 829
 830	pending_snapshot->dentry = dentry;
 831	pending_snapshot->root = root;
 832	pending_snapshot->readonly = readonly;
 833	pending_snapshot->dir = dir;
 834	pending_snapshot->inherit = inherit;
 835
 836	trans = btrfs_start_transaction(root, 0);
 837	if (IS_ERR(trans)) {
 838		ret = PTR_ERR(trans);
 839		goto fail;
 840	}
 841
 842	trans->pending_snapshot = pending_snapshot;
 
 843
 844	ret = btrfs_commit_transaction(trans);
 845	if (ret)
 846		goto fail;
 
 
 
 
 
 
 
 
 
 
 847
 848	ret = pending_snapshot->error;
 849	if (ret)
 850		goto fail;
 851
 852	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 853	if (ret)
 854		goto fail;
 855
 856	inode = btrfs_lookup_dentry(d_inode(dentry->d_parent), dentry);
 857	if (IS_ERR(inode)) {
 858		ret = PTR_ERR(inode);
 859		goto fail;
 860	}
 861
 862	d_instantiate(dentry, inode);
 863	ret = 0;
 864	pending_snapshot->anon_dev = 0;
 865fail:
 866	/* Prevent double freeing of anon_dev */
 867	if (ret && pending_snapshot->snap)
 868		pending_snapshot->snap->anon_dev = 0;
 869	btrfs_put_root(pending_snapshot->snap);
 870	btrfs_subvolume_release_metadata(root, &pending_snapshot->block_rsv);
 871free_pending:
 872	if (pending_snapshot->anon_dev)
 873		free_anon_bdev(pending_snapshot->anon_dev);
 874	kfree(pending_snapshot->root_item);
 875	btrfs_free_path(pending_snapshot->path);
 876	kfree(pending_snapshot);
 877
 878	return ret;
 879}
 880
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 881/*  copy of may_delete in fs/namei.c()
 882 *	Check whether we can remove a link victim from directory dir, check
 883 *  whether the type of victim is right.
 884 *  1. We can't do it if dir is read-only (done in permission())
 885 *  2. We should have write and exec permissions on dir
 886 *  3. We can't remove anything from append-only dir
 887 *  4. We can't do anything with immutable dir (done in permission())
 888 *  5. If the sticky bit on dir is set we should either
 889 *	a. be owner of dir, or
 890 *	b. be owner of victim, or
 891 *	c. have CAP_FOWNER capability
 892 *  6. If the victim is append-only or immutable we can't do anything with
 893 *     links pointing to it.
 894 *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 895 *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 896 *  9. We can't remove a root or mountpoint.
 897 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 898 *     nfs_async_unlink().
 899 */
 900
 901static int btrfs_may_delete(struct user_namespace *mnt_userns,
 902			    struct inode *dir, struct dentry *victim, int isdir)
 903{
 904	int error;
 905
 906	if (d_really_is_negative(victim))
 907		return -ENOENT;
 908
 909	BUG_ON(d_inode(victim->d_parent) != dir);
 910	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
 911
 912	error = inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 913	if (error)
 914		return error;
 915	if (IS_APPEND(dir))
 916		return -EPERM;
 917	if (check_sticky(mnt_userns, dir, d_inode(victim)) ||
 918	    IS_APPEND(d_inode(victim)) || IS_IMMUTABLE(d_inode(victim)) ||
 919	    IS_SWAPFILE(d_inode(victim)))
 920		return -EPERM;
 921	if (isdir) {
 922		if (!d_is_dir(victim))
 923			return -ENOTDIR;
 924		if (IS_ROOT(victim))
 925			return -EBUSY;
 926	} else if (d_is_dir(victim))
 927		return -EISDIR;
 928	if (IS_DEADDIR(dir))
 929		return -ENOENT;
 930	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 931		return -EBUSY;
 932	return 0;
 933}
 934
 935/* copy of may_create in fs/namei.c() */
 936static inline int btrfs_may_create(struct user_namespace *mnt_userns,
 937				   struct inode *dir, struct dentry *child)
 938{
 939	if (d_really_is_positive(child))
 940		return -EEXIST;
 941	if (IS_DEADDIR(dir))
 942		return -ENOENT;
 943	if (!fsuidgid_has_mapping(dir->i_sb, mnt_userns))
 944		return -EOVERFLOW;
 945	return inode_permission(mnt_userns, dir, MAY_WRITE | MAY_EXEC);
 946}
 947
 948/*
 949 * Create a new subvolume below @parent.  This is largely modeled after
 950 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 951 * inside this filesystem so it's quite a bit simpler.
 952 */
 953static noinline int btrfs_mksubvol(const struct path *parent,
 954				   struct user_namespace *mnt_userns,
 955				   const char *name, int namelen,
 956				   struct btrfs_root *snap_src,
 957				   bool readonly,
 958				   struct btrfs_qgroup_inherit *inherit)
 959{
 960	struct inode *dir = d_inode(parent->dentry);
 961	struct btrfs_fs_info *fs_info = btrfs_sb(dir->i_sb);
 962	struct dentry *dentry;
 963	struct fscrypt_str name_str = FSTR_INIT((char *)name, namelen);
 964	int error;
 965
 966	error = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
 967	if (error == -EINTR)
 968		return error;
 969
 970	dentry = lookup_one(mnt_userns, name, parent->dentry, namelen);
 971	error = PTR_ERR(dentry);
 972	if (IS_ERR(dentry))
 973		goto out_unlock;
 974
 975	error = btrfs_may_create(mnt_userns, dir, dentry);
 976	if (error)
 977		goto out_dput;
 978
 979	/*
 980	 * even if this name doesn't exist, we may get hash collisions.
 981	 * check for them now when we can safely fail
 982	 */
 983	error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
 984					       dir->i_ino, &name_str);
 985	if (error)
 986		goto out_dput;
 987
 988	down_read(&fs_info->subvol_sem);
 
 
 
 
 989
 990	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 991		goto out_up_read;
 992
 993	if (snap_src)
 994		error = create_snapshot(snap_src, dir, dentry, readonly, inherit);
 995	else
 996		error = create_subvol(mnt_userns, dir, dentry, inherit);
 997
 
 
 998	if (!error)
 999		fsnotify_mkdir(dir, dentry);
1000out_up_read:
1001	up_read(&fs_info->subvol_sem);
 
 
1002out_dput:
1003	dput(dentry);
1004out_unlock:
1005	btrfs_inode_unlock(BTRFS_I(dir), 0);
1006	return error;
1007}
1008
1009static noinline int btrfs_mksnapshot(const struct path *parent,
1010				   struct user_namespace *mnt_userns,
1011				   const char *name, int namelen,
1012				   struct btrfs_root *root,
1013				   bool readonly,
1014				   struct btrfs_qgroup_inherit *inherit)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1015{
 
 
 
 
 
 
1016	int ret;
1017	bool snapshot_force_cow = false;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1018
1019	/*
1020	 * Force new buffered writes to reserve space even when NOCOW is
1021	 * possible. This is to avoid later writeback (running dealloc) to
1022	 * fallback to COW mode and unexpectedly fail with ENOSPC.
1023	 */
1024	btrfs_drew_read_lock(&root->snapshot_lock);
 
 
1025
1026	ret = btrfs_start_delalloc_snapshot(root, false);
1027	if (ret)
1028		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1029
1030	/*
1031	 * All previous writes have started writeback in NOCOW mode, so now
1032	 * we force future writes to fallback to COW mode during snapshot
1033	 * creation.
1034	 */
1035	atomic_inc(&root->snapshot_force_cow);
1036	snapshot_force_cow = true;
 
 
1037
1038	btrfs_wait_ordered_extents(root, U64_MAX, 0, (u64)-1);
 
 
1039
1040	ret = btrfs_mksubvol(parent, mnt_userns, name, namelen,
1041			     root, readonly, inherit);
 
 
 
 
 
 
 
 
 
 
 
 
 
1042out:
1043	if (snapshot_force_cow)
1044		atomic_dec(&root->snapshot_force_cow);
1045	btrfs_drew_read_unlock(&root->snapshot_lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1046	return ret;
1047}
1048
1049/*
1050 * Try to start exclusive operation @type or cancel it if it's running.
 
 
1051 *
1052 * Return:
1053 *   0        - normal mode, newly claimed op started
1054 *  >0        - normal mode, something else is running,
1055 *              return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS to user space
1056 * ECANCELED  - cancel mode, successful cancel
1057 * ENOTCONN   - cancel mode, operation not running anymore
1058 */
1059static int exclop_start_or_cancel_reloc(struct btrfs_fs_info *fs_info,
1060			enum btrfs_exclusive_operation type, bool cancel)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1061{
1062	if (!cancel) {
1063		/* Start normal op */
1064		if (!btrfs_exclop_start(fs_info, type))
1065			return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
1066		/* Exclusive operation is now claimed */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1067		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
1068	}
1069
1070	/* Cancel running op */
1071	if (btrfs_exclop_start_try_lock(fs_info, type)) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1072		/*
1073		 * This blocks any exclop finish from setting it to NONE, so we
1074		 * request cancellation. Either it runs and we will wait for it,
1075		 * or it has finished and no waiting will happen.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1076		 */
1077		atomic_inc(&fs_info->reloc_cancel_req);
1078		btrfs_exclop_start_unlock(fs_info);
 
 
 
 
 
 
1079
1080		if (test_bit(BTRFS_FS_RELOC_RUNNING, &fs_info->flags))
1081			wait_on_bit(&fs_info->flags, BTRFS_FS_RELOC_RUNNING,
1082				    TASK_INTERRUPTIBLE);
 
1083
1084		return -ECANCELED;
 
 
 
 
1085	}
1086
1087	/* Something else is running or none */
1088	return -ENOTCONN;
 
 
 
 
 
1089}
1090
1091static noinline int btrfs_ioctl_resize(struct file *file,
1092					void __user *arg)
1093{
1094	BTRFS_DEV_LOOKUP_ARGS(args);
1095	struct inode *inode = file_inode(file);
1096	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1097	u64 new_size;
1098	u64 old_size;
1099	u64 devid = 1;
1100	struct btrfs_root *root = BTRFS_I(inode)->root;
1101	struct btrfs_ioctl_vol_args *vol_args;
1102	struct btrfs_trans_handle *trans;
1103	struct btrfs_device *device = NULL;
1104	char *sizestr;
1105	char *retptr;
1106	char *devstr = NULL;
1107	int ret = 0;
1108	int mod = 0;
1109	bool cancel;
 
 
1110
1111	if (!capable(CAP_SYS_ADMIN))
1112		return -EPERM;
1113
1114	ret = mnt_want_write_file(file);
1115	if (ret)
1116		return ret;
 
 
 
1117
1118	/*
1119	 * Read the arguments before checking exclusivity to be able to
1120	 * distinguish regular resize and cancel
1121	 */
1122	vol_args = memdup_user(arg, sizeof(*vol_args));
1123	if (IS_ERR(vol_args)) {
1124		ret = PTR_ERR(vol_args);
1125		goto out_drop;
1126	}
 
1127	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1128	sizestr = vol_args->name;
1129	cancel = (strcmp("cancel", sizestr) == 0);
1130	ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_RESIZE, cancel);
1131	if (ret)
1132		goto out_free;
1133	/* Exclusive operation is now claimed */
1134
 
1135	devstr = strchr(sizestr, ':');
1136	if (devstr) {
 
1137		sizestr = devstr + 1;
1138		*devstr = '\0';
1139		devstr = vol_args->name;
1140		ret = kstrtoull(devstr, 10, &devid);
1141		if (ret)
1142			goto out_finish;
1143		if (!devid) {
1144			ret = -EINVAL;
1145			goto out_finish;
1146		}
1147		btrfs_info(fs_info, "resizing devid %llu", devid);
1148	}
1149
1150	args.devid = devid;
1151	device = btrfs_find_device(fs_info->fs_devices, &args);
1152	if (!device) {
1153		btrfs_info(fs_info, "resizer unable to find device %llu",
1154			   devid);
1155		ret = -ENODEV;
1156		goto out_finish;
1157	}
1158
1159	if (!test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) {
1160		btrfs_info(fs_info,
1161			   "resizer unable to apply on readonly device %llu",
1162		       devid);
1163		ret = -EPERM;
1164		goto out_finish;
1165	}
1166
1167	if (!strcmp(sizestr, "max"))
1168		new_size = bdev_nr_bytes(device->bdev);
1169	else {
1170		if (sizestr[0] == '-') {
1171			mod = -1;
1172			sizestr++;
1173		} else if (sizestr[0] == '+') {
1174			mod = 1;
1175			sizestr++;
1176		}
1177		new_size = memparse(sizestr, &retptr);
1178		if (*retptr != '\0' || new_size == 0) {
1179			ret = -EINVAL;
1180			goto out_finish;
1181		}
1182	}
1183
1184	if (test_bit(BTRFS_DEV_STATE_REPLACE_TGT, &device->dev_state)) {
1185		ret = -EPERM;
1186		goto out_finish;
1187	}
1188
1189	old_size = btrfs_device_get_total_bytes(device);
1190
1191	if (mod < 0) {
1192		if (new_size > old_size) {
1193			ret = -EINVAL;
1194			goto out_finish;
1195		}
1196		new_size = old_size - new_size;
1197	} else if (mod > 0) {
1198		if (new_size > ULLONG_MAX - old_size) {
1199			ret = -ERANGE;
1200			goto out_finish;
1201		}
1202		new_size = old_size + new_size;
1203	}
1204
1205	if (new_size < SZ_256M) {
1206		ret = -EINVAL;
1207		goto out_finish;
1208	}
1209	if (new_size > bdev_nr_bytes(device->bdev)) {
1210		ret = -EFBIG;
1211		goto out_finish;
1212	}
1213
1214	new_size = round_down(new_size, fs_info->sectorsize);
 
 
 
 
 
1215
1216	if (new_size > old_size) {
1217		trans = btrfs_start_transaction(root, 0);
1218		if (IS_ERR(trans)) {
1219			ret = PTR_ERR(trans);
1220			goto out_finish;
1221		}
1222		ret = btrfs_grow_device(trans, device, new_size);
1223		btrfs_commit_transaction(trans);
1224	} else if (new_size < old_size) {
1225		ret = btrfs_shrink_device(device, new_size);
1226	} /* equal, nothing need to do */
1227
1228	if (ret == 0 && new_size != old_size)
1229		btrfs_info_in_rcu(fs_info,
1230			"resize device %s (devid %llu) from %llu to %llu",
1231			btrfs_dev_name(device), device->devid,
1232			old_size, new_size);
1233out_finish:
1234	btrfs_exclop_finish(fs_info);
1235out_free:
1236	kfree(vol_args);
1237out_drop:
1238	mnt_drop_write_file(file);
1239	return ret;
1240}
1241
1242static noinline int __btrfs_ioctl_snap_create(struct file *file,
1243				struct user_namespace *mnt_userns,
1244				const char *name, unsigned long fd, int subvol,
1245				bool readonly,
1246				struct btrfs_qgroup_inherit *inherit)
 
1247{
 
 
1248	int namelen;
1249	int ret = 0;
1250
1251	if (!S_ISDIR(file_inode(file)->i_mode))
1252		return -ENOTDIR;
1253
1254	ret = mnt_want_write_file(file);
1255	if (ret)
1256		goto out;
1257
1258	namelen = strlen(name);
1259	if (strchr(name, '/')) {
1260		ret = -EINVAL;
1261		goto out_drop_write;
1262	}
1263
1264	if (name[0] == '.' &&
1265	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1266		ret = -EEXIST;
1267		goto out_drop_write;
1268	}
1269
1270	if (subvol) {
1271		ret = btrfs_mksubvol(&file->f_path, mnt_userns, name,
1272				     namelen, NULL, readonly, inherit);
1273	} else {
1274		struct fd src = fdget(fd);
1275		struct inode *src_inode;
1276		if (!src.file) {
 
1277			ret = -EINVAL;
1278			goto out_drop_write;
1279		}
1280
1281		src_inode = file_inode(src.file);
1282		if (src_inode->i_sb != file_inode(file)->i_sb) {
1283			btrfs_info(BTRFS_I(file_inode(file))->root->fs_info,
1284				   "Snapshot src from another FS");
1285			ret = -EXDEV;
1286		} else if (!inode_owner_or_capable(mnt_userns, src_inode)) {
1287			/*
1288			 * Subvolume creation is not restricted, but snapshots
1289			 * are limited to own subvolumes only
1290			 */
1291			ret = -EPERM;
1292		} else {
1293			ret = btrfs_mksnapshot(&file->f_path, mnt_userns,
1294					       name, namelen,
1295					       BTRFS_I(src_inode)->root,
1296					       readonly, inherit);
1297		}
1298		fdput(src);
 
 
 
1299	}
1300out_drop_write:
1301	mnt_drop_write_file(file);
1302out:
1303	return ret;
1304}
1305
1306static noinline int btrfs_ioctl_snap_create(struct file *file,
1307					    void __user *arg, int subvol)
1308{
1309	struct btrfs_ioctl_vol_args *vol_args;
1310	int ret;
1311
1312	if (!S_ISDIR(file_inode(file)->i_mode))
1313		return -ENOTDIR;
1314
1315	vol_args = memdup_user(arg, sizeof(*vol_args));
1316	if (IS_ERR(vol_args))
1317		return PTR_ERR(vol_args);
1318	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1319
1320	ret = __btrfs_ioctl_snap_create(file, file_mnt_user_ns(file),
1321					vol_args->name, vol_args->fd, subvol,
1322					false, NULL);
1323
1324	kfree(vol_args);
1325	return ret;
1326}
1327
1328static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1329					       void __user *arg, int subvol)
1330{
1331	struct btrfs_ioctl_vol_args_v2 *vol_args;
1332	int ret;
 
 
1333	bool readonly = false;
1334	struct btrfs_qgroup_inherit *inherit = NULL;
1335
1336	if (!S_ISDIR(file_inode(file)->i_mode))
1337		return -ENOTDIR;
1338
1339	vol_args = memdup_user(arg, sizeof(*vol_args));
1340	if (IS_ERR(vol_args))
1341		return PTR_ERR(vol_args);
1342	vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1343
1344	if (vol_args->flags & ~BTRFS_SUBVOL_CREATE_ARGS_MASK) {
 
1345		ret = -EOPNOTSUPP;
1346		goto free_args;
1347	}
1348
 
 
1349	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1350		readonly = true;
1351	if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
1352		u64 nums;
1353
1354		if (vol_args->size < sizeof(*inherit) ||
1355		    vol_args->size > PAGE_SIZE) {
1356			ret = -EINVAL;
1357			goto free_args;
1358		}
1359		inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
1360		if (IS_ERR(inherit)) {
1361			ret = PTR_ERR(inherit);
1362			goto free_args;
1363		}
1364
1365		if (inherit->num_qgroups > PAGE_SIZE ||
1366		    inherit->num_ref_copies > PAGE_SIZE ||
1367		    inherit->num_excl_copies > PAGE_SIZE) {
1368			ret = -EINVAL;
1369			goto free_inherit;
1370		}
1371
1372		nums = inherit->num_qgroups + 2 * inherit->num_ref_copies +
1373		       2 * inherit->num_excl_copies;
1374		if (vol_args->size != struct_size(inherit, qgroups, nums)) {
1375			ret = -EINVAL;
1376			goto free_inherit;
1377		}
1378	}
1379
1380	ret = __btrfs_ioctl_snap_create(file, file_mnt_user_ns(file),
1381					vol_args->name, vol_args->fd, subvol,
1382					readonly, inherit);
1383	if (ret)
1384		goto free_inherit;
1385free_inherit:
1386	kfree(inherit);
1387free_args:
1388	kfree(vol_args);
1389	return ret;
1390}
1391
1392static noinline int btrfs_ioctl_subvol_getflags(struct inode *inode,
1393						void __user *arg)
1394{
1395	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1396	struct btrfs_root *root = BTRFS_I(inode)->root;
1397	int ret = 0;
1398	u64 flags = 0;
1399
1400	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID)
1401		return -EINVAL;
1402
1403	down_read(&fs_info->subvol_sem);
1404	if (btrfs_root_readonly(root))
1405		flags |= BTRFS_SUBVOL_RDONLY;
1406	up_read(&fs_info->subvol_sem);
1407
1408	if (copy_to_user(arg, &flags, sizeof(flags)))
1409		ret = -EFAULT;
1410
1411	return ret;
1412}
1413
1414static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1415					      void __user *arg)
1416{
1417	struct inode *inode = file_inode(file);
1418	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
1419	struct btrfs_root *root = BTRFS_I(inode)->root;
1420	struct btrfs_trans_handle *trans;
1421	u64 root_flags;
1422	u64 flags;
1423	int ret = 0;
1424
1425	if (!inode_owner_or_capable(file_mnt_user_ns(file), inode))
1426		return -EPERM;
1427
1428	ret = mnt_want_write_file(file);
1429	if (ret)
1430		goto out;
1431
1432	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
1433		ret = -EINVAL;
1434		goto out_drop_write;
1435	}
1436
1437	if (copy_from_user(&flags, arg, sizeof(flags))) {
1438		ret = -EFAULT;
1439		goto out_drop_write;
1440	}
1441
1442	if (flags & ~BTRFS_SUBVOL_RDONLY) {
1443		ret = -EOPNOTSUPP;
1444		goto out_drop_write;
1445	}
 
1446
1447	down_write(&fs_info->subvol_sem);
1448
1449	/* nothing to do */
1450	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1451		goto out_drop_sem;
1452
1453	root_flags = btrfs_root_flags(&root->root_item);
1454	if (flags & BTRFS_SUBVOL_RDONLY) {
1455		btrfs_set_root_flags(&root->root_item,
1456				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1457	} else {
1458		/*
1459		 * Block RO -> RW transition if this subvolume is involved in
1460		 * send
1461		 */
1462		spin_lock(&root->root_item_lock);
1463		if (root->send_in_progress == 0) {
1464			btrfs_set_root_flags(&root->root_item,
1465				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
1466			spin_unlock(&root->root_item_lock);
1467		} else {
1468			spin_unlock(&root->root_item_lock);
1469			btrfs_warn(fs_info,
1470				   "Attempt to set subvolume %llu read-write during send",
1471				   root->root_key.objectid);
1472			ret = -EPERM;
1473			goto out_drop_sem;
1474		}
1475	}
1476
1477	trans = btrfs_start_transaction(root, 1);
1478	if (IS_ERR(trans)) {
1479		ret = PTR_ERR(trans);
1480		goto out_reset;
1481	}
1482
1483	ret = btrfs_update_root(trans, fs_info->tree_root,
1484				&root->root_key, &root->root_item);
1485	if (ret < 0) {
1486		btrfs_end_transaction(trans);
1487		goto out_reset;
1488	}
1489
1490	ret = btrfs_commit_transaction(trans);
1491
 
1492out_reset:
1493	if (ret)
1494		btrfs_set_root_flags(&root->root_item, root_flags);
1495out_drop_sem:
1496	up_write(&fs_info->subvol_sem);
1497out_drop_write:
1498	mnt_drop_write_file(file);
1499out:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1500	return ret;
1501}
1502
1503static noinline int key_in_sk(struct btrfs_key *key,
1504			      struct btrfs_ioctl_search_key *sk)
1505{
1506	struct btrfs_key test;
1507	int ret;
1508
1509	test.objectid = sk->min_objectid;
1510	test.type = sk->min_type;
1511	test.offset = sk->min_offset;
1512
1513	ret = btrfs_comp_cpu_keys(key, &test);
1514	if (ret < 0)
1515		return 0;
1516
1517	test.objectid = sk->max_objectid;
1518	test.type = sk->max_type;
1519	test.offset = sk->max_offset;
1520
1521	ret = btrfs_comp_cpu_keys(key, &test);
1522	if (ret > 0)
1523		return 0;
1524	return 1;
1525}
1526
1527static noinline int copy_to_sk(struct btrfs_path *path,
 
1528			       struct btrfs_key *key,
1529			       struct btrfs_ioctl_search_key *sk,
1530			       size_t *buf_size,
1531			       char __user *ubuf,
1532			       unsigned long *sk_offset,
1533			       int *num_found)
1534{
1535	u64 found_transid;
1536	struct extent_buffer *leaf;
1537	struct btrfs_ioctl_search_header sh;
1538	struct btrfs_key test;
1539	unsigned long item_off;
1540	unsigned long item_len;
1541	int nritems;
1542	int i;
1543	int slot;
1544	int ret = 0;
1545
1546	leaf = path->nodes[0];
1547	slot = path->slots[0];
1548	nritems = btrfs_header_nritems(leaf);
1549
1550	if (btrfs_header_generation(leaf) > sk->max_transid) {
1551		i = nritems;
1552		goto advance_key;
1553	}
1554	found_transid = btrfs_header_generation(leaf);
1555
1556	for (i = slot; i < nritems; i++) {
1557		item_off = btrfs_item_ptr_offset(leaf, i);
1558		item_len = btrfs_item_size(leaf, i);
1559
1560		btrfs_item_key_to_cpu(leaf, key, i);
1561		if (!key_in_sk(key, sk))
1562			continue;
1563
1564		if (sizeof(sh) + item_len > *buf_size) {
1565			if (*num_found) {
1566				ret = 1;
1567				goto out;
1568			}
1569
1570			/*
1571			 * return one empty item back for v1, which does not
1572			 * handle -EOVERFLOW
1573			 */
1574
1575			*buf_size = sizeof(sh) + item_len;
1576			item_len = 0;
1577			ret = -EOVERFLOW;
1578		}
1579
1580		if (sizeof(sh) + item_len + *sk_offset > *buf_size) {
 
1581			ret = 1;
1582			goto out;
1583		}
1584
 
 
 
 
1585		sh.objectid = key->objectid;
1586		sh.offset = key->offset;
1587		sh.type = key->type;
1588		sh.len = item_len;
1589		sh.transid = found_transid;
1590
1591		/*
1592		 * Copy search result header. If we fault then loop again so we
1593		 * can fault in the pages and -EFAULT there if there's a
1594		 * problem. Otherwise we'll fault and then copy the buffer in
1595		 * properly this next time through
1596		 */
1597		if (copy_to_user_nofault(ubuf + *sk_offset, &sh, sizeof(sh))) {
1598			ret = 0;
1599			goto out;
1600		}
1601
1602		*sk_offset += sizeof(sh);
1603
1604		if (item_len) {
1605			char __user *up = ubuf + *sk_offset;
1606			/*
1607			 * Copy the item, same behavior as above, but reset the
1608			 * * sk_offset so we copy the full thing again.
1609			 */
1610			if (read_extent_buffer_to_user_nofault(leaf, up,
1611						item_off, item_len)) {
1612				ret = 0;
1613				*sk_offset -= sizeof(sh);
1614				goto out;
1615			}
1616
1617			*sk_offset += item_len;
1618		}
1619		(*num_found)++;
1620
1621		if (ret) /* -EOVERFLOW from above */
1622			goto out;
1623
1624		if (*num_found >= sk->nr_items) {
1625			ret = 1;
1626			goto out;
1627		}
1628	}
1629advance_key:
1630	ret = 0;
1631	test.objectid = sk->max_objectid;
1632	test.type = sk->max_type;
1633	test.offset = sk->max_offset;
1634	if (btrfs_comp_cpu_keys(key, &test) >= 0)
1635		ret = 1;
1636	else if (key->offset < (u64)-1)
1637		key->offset++;
1638	else if (key->type < (u8)-1) {
1639		key->offset = 0;
1640		key->type++;
1641	} else if (key->objectid < (u64)-1) {
1642		key->offset = 0;
1643		key->type = 0;
1644		key->objectid++;
1645	} else
1646		ret = 1;
1647out:
1648	/*
1649	 *  0: all items from this leaf copied, continue with next
1650	 *  1: * more items can be copied, but unused buffer is too small
1651	 *     * all items were found
1652	 *     Either way, it will stops the loop which iterates to the next
1653	 *     leaf
1654	 *  -EOVERFLOW: item was to large for buffer
1655	 *  -EFAULT: could not copy extent buffer back to userspace
1656	 */
1657	return ret;
1658}
1659
1660static noinline int search_ioctl(struct inode *inode,
1661				 struct btrfs_ioctl_search_key *sk,
1662				 size_t *buf_size,
1663				 char __user *ubuf)
1664{
1665	struct btrfs_fs_info *info = btrfs_sb(inode->i_sb);
1666	struct btrfs_root *root;
1667	struct btrfs_key key;
 
1668	struct btrfs_path *path;
 
 
1669	int ret;
1670	int num_found = 0;
1671	unsigned long sk_offset = 0;
1672
1673	if (*buf_size < sizeof(struct btrfs_ioctl_search_header)) {
1674		*buf_size = sizeof(struct btrfs_ioctl_search_header);
1675		return -EOVERFLOW;
1676	}
1677
1678	path = btrfs_alloc_path();
1679	if (!path)
1680		return -ENOMEM;
1681
1682	if (sk->tree_id == 0) {
1683		/* search the root of the inode that was passed */
1684		root = btrfs_grab_root(BTRFS_I(inode)->root);
1685	} else {
1686		root = btrfs_get_fs_root(info, sk->tree_id, true);
 
 
 
1687		if (IS_ERR(root)) {
 
 
1688			btrfs_free_path(path);
1689			return PTR_ERR(root);
1690		}
1691	}
1692
1693	key.objectid = sk->min_objectid;
1694	key.type = sk->min_type;
1695	key.offset = sk->min_offset;
1696
1697	while (1) {
1698		ret = -EFAULT;
1699		/*
1700		 * Ensure that the whole user buffer is faulted in at sub-page
1701		 * granularity, otherwise the loop may live-lock.
1702		 */
1703		if (fault_in_subpage_writeable(ubuf + sk_offset,
1704					       *buf_size - sk_offset))
1705			break;
1706
1707		ret = btrfs_search_forward(root, &key, path, sk->min_transid);
1708		if (ret != 0) {
1709			if (ret > 0)
1710				ret = 0;
1711			goto err;
1712		}
1713		ret = copy_to_sk(path, &key, sk, buf_size, ubuf,
1714				 &sk_offset, &num_found);
1715		btrfs_release_path(path);
1716		if (ret)
1717			break;
1718
1719	}
1720	if (ret > 0)
1721		ret = 0;
1722err:
1723	sk->nr_items = num_found;
1724	btrfs_put_root(root);
1725	btrfs_free_path(path);
1726	return ret;
1727}
1728
1729static noinline int btrfs_ioctl_tree_search(struct inode *inode,
1730					    void __user *argp)
1731{
1732	struct btrfs_ioctl_search_args __user *uargs = argp;
1733	struct btrfs_ioctl_search_key sk;
1734	int ret;
1735	size_t buf_size;
1736
1737	if (!capable(CAP_SYS_ADMIN))
1738		return -EPERM;
1739
1740	if (copy_from_user(&sk, &uargs->key, sizeof(sk)))
1741		return -EFAULT;
1742
1743	buf_size = sizeof(uargs->buf);
1744
1745	ret = search_ioctl(inode, &sk, &buf_size, uargs->buf);
1746
1747	/*
1748	 * In the origin implementation an overflow is handled by returning a
1749	 * search header with a len of zero, so reset ret.
1750	 */
1751	if (ret == -EOVERFLOW)
1752		ret = 0;
1753
1754	if (ret == 0 && copy_to_user(&uargs->key, &sk, sizeof(sk)))
1755		ret = -EFAULT;
1756	return ret;
1757}
1758
1759static noinline int btrfs_ioctl_tree_search_v2(struct inode *inode,
1760					       void __user *argp)
1761{
1762	struct btrfs_ioctl_search_args_v2 __user *uarg = argp;
1763	struct btrfs_ioctl_search_args_v2 args;
1764	int ret;
1765	size_t buf_size;
1766	const size_t buf_limit = SZ_16M;
1767
1768	if (!capable(CAP_SYS_ADMIN))
1769		return -EPERM;
1770
1771	/* copy search header and buffer size */
1772	if (copy_from_user(&args, uarg, sizeof(args)))
1773		return -EFAULT;
1774
1775	buf_size = args.buf_size;
1776
1777	/* limit result size to 16MB */
1778	if (buf_size > buf_limit)
1779		buf_size = buf_limit;
1780
1781	ret = search_ioctl(inode, &args.key, &buf_size,
1782			   (char __user *)(&uarg->buf[0]));
1783	if (ret == 0 && copy_to_user(&uarg->key, &args.key, sizeof(args.key)))
1784		ret = -EFAULT;
1785	else if (ret == -EOVERFLOW &&
1786		copy_to_user(&uarg->buf_size, &buf_size, sizeof(buf_size)))
1787		ret = -EFAULT;
1788
1789	return ret;
1790}
1791
1792/*
1793 * Search INODE_REFs to identify path name of 'dirid' directory
1794 * in a 'tree_id' tree. and sets path name to 'name'.
1795 */
1796static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1797				u64 tree_id, u64 dirid, char *name)
1798{
1799	struct btrfs_root *root;
1800	struct btrfs_key key;
1801	char *ptr;
1802	int ret = -1;
1803	int slot;
1804	int len;
1805	int total_len = 0;
1806	struct btrfs_inode_ref *iref;
1807	struct extent_buffer *l;
1808	struct btrfs_path *path;
1809
1810	if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1811		name[0]='\0';
1812		return 0;
1813	}
1814
1815	path = btrfs_alloc_path();
1816	if (!path)
1817		return -ENOMEM;
1818
1819	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX - 1];
1820
1821	root = btrfs_get_fs_root(info, tree_id, true);
 
 
 
1822	if (IS_ERR(root)) {
1823		ret = PTR_ERR(root);
1824		root = NULL;
1825		goto out;
1826	}
1827
1828	key.objectid = dirid;
1829	key.type = BTRFS_INODE_REF_KEY;
1830	key.offset = (u64)-1;
1831
1832	while (1) {
1833		ret = btrfs_search_backwards(root, &key, path);
1834		if (ret < 0)
1835			goto out;
1836		else if (ret > 0) {
1837			ret = -ENOENT;
1838			goto out;
1839		}
1840
1841		l = path->nodes[0];
1842		slot = path->slots[0];
 
 
 
 
 
 
 
 
 
1843
1844		iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1845		len = btrfs_inode_ref_name_len(l, iref);
1846		ptr -= len + 1;
1847		total_len += len + 1;
1848		if (ptr < name) {
1849			ret = -ENAMETOOLONG;
1850			goto out;
1851		}
1852
1853		*(ptr + len) = '/';
1854		read_extent_buffer(l, ptr, (unsigned long)(iref + 1), len);
1855
1856		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1857			break;
1858
1859		btrfs_release_path(path);
1860		key.objectid = key.offset;
1861		key.offset = (u64)-1;
1862		dirid = key.objectid;
1863	}
 
 
1864	memmove(name, ptr, total_len);
1865	name[total_len] = '\0';
1866	ret = 0;
1867out:
1868	btrfs_put_root(root);
1869	btrfs_free_path(path);
1870	return ret;
1871}
1872
1873static int btrfs_search_path_in_tree_user(struct user_namespace *mnt_userns,
1874				struct inode *inode,
1875				struct btrfs_ioctl_ino_lookup_user_args *args)
1876{
1877	struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
1878	struct super_block *sb = inode->i_sb;
1879	struct btrfs_key upper_limit = BTRFS_I(inode)->location;
1880	u64 treeid = BTRFS_I(inode)->root->root_key.objectid;
1881	u64 dirid = args->dirid;
1882	unsigned long item_off;
1883	unsigned long item_len;
1884	struct btrfs_inode_ref *iref;
1885	struct btrfs_root_ref *rref;
1886	struct btrfs_root *root = NULL;
1887	struct btrfs_path *path;
1888	struct btrfs_key key, key2;
1889	struct extent_buffer *leaf;
1890	struct inode *temp_inode;
1891	char *ptr;
1892	int slot;
1893	int len;
1894	int total_len = 0;
1895	int ret;
1896
1897	path = btrfs_alloc_path();
1898	if (!path)
1899		return -ENOMEM;
1900
1901	/*
1902	 * If the bottom subvolume does not exist directly under upper_limit,
1903	 * construct the path in from the bottom up.
1904	 */
1905	if (dirid != upper_limit.objectid) {
1906		ptr = &args->path[BTRFS_INO_LOOKUP_USER_PATH_MAX - 1];
1907
1908		root = btrfs_get_fs_root(fs_info, treeid, true);
1909		if (IS_ERR(root)) {
1910			ret = PTR_ERR(root);
1911			goto out;
1912		}
1913
1914		key.objectid = dirid;
1915		key.type = BTRFS_INODE_REF_KEY;
1916		key.offset = (u64)-1;
1917		while (1) {
1918			ret = btrfs_search_backwards(root, &key, path);
1919			if (ret < 0)
1920				goto out_put;
1921			else if (ret > 0) {
1922				ret = -ENOENT;
1923				goto out_put;
1924			}
1925
1926			leaf = path->nodes[0];
1927			slot = path->slots[0];
1928
1929			iref = btrfs_item_ptr(leaf, slot, struct btrfs_inode_ref);
1930			len = btrfs_inode_ref_name_len(leaf, iref);
1931			ptr -= len + 1;
1932			total_len += len + 1;
1933			if (ptr < args->path) {
1934				ret = -ENAMETOOLONG;
1935				goto out_put;
1936			}
1937
1938			*(ptr + len) = '/';
1939			read_extent_buffer(leaf, ptr,
1940					(unsigned long)(iref + 1), len);
1941
1942			/* Check the read+exec permission of this directory */
1943			ret = btrfs_previous_item(root, path, dirid,
1944						  BTRFS_INODE_ITEM_KEY);
1945			if (ret < 0) {
1946				goto out_put;
1947			} else if (ret > 0) {
1948				ret = -ENOENT;
1949				goto out_put;
1950			}
1951
1952			leaf = path->nodes[0];
1953			slot = path->slots[0];
1954			btrfs_item_key_to_cpu(leaf, &key2, slot);
1955			if (key2.objectid != dirid) {
1956				ret = -ENOENT;
1957				goto out_put;
1958			}
1959
1960			temp_inode = btrfs_iget(sb, key2.objectid, root);
1961			if (IS_ERR(temp_inode)) {
1962				ret = PTR_ERR(temp_inode);
1963				goto out_put;
1964			}
1965			ret = inode_permission(mnt_userns, temp_inode,
1966					       MAY_READ | MAY_EXEC);
1967			iput(temp_inode);
1968			if (ret) {
1969				ret = -EACCES;
1970				goto out_put;
1971			}
1972
1973			if (key.offset == upper_limit.objectid)
1974				break;
1975			if (key.objectid == BTRFS_FIRST_FREE_OBJECTID) {
1976				ret = -EACCES;
1977				goto out_put;
1978			}
1979
1980			btrfs_release_path(path);
1981			key.objectid = key.offset;
1982			key.offset = (u64)-1;
1983			dirid = key.objectid;
1984		}
1985
1986		memmove(args->path, ptr, total_len);
1987		args->path[total_len] = '\0';
1988		btrfs_put_root(root);
1989		root = NULL;
1990		btrfs_release_path(path);
1991	}
1992
1993	/* Get the bottom subvolume's name from ROOT_REF */
1994	key.objectid = treeid;
1995	key.type = BTRFS_ROOT_REF_KEY;
1996	key.offset = args->treeid;
1997	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
1998	if (ret < 0) {
1999		goto out;
2000	} else if (ret > 0) {
2001		ret = -ENOENT;
2002		goto out;
2003	}
2004
2005	leaf = path->nodes[0];
2006	slot = path->slots[0];
2007	btrfs_item_key_to_cpu(leaf, &key, slot);
2008
2009	item_off = btrfs_item_ptr_offset(leaf, slot);
2010	item_len = btrfs_item_size(leaf, slot);
2011	/* Check if dirid in ROOT_REF corresponds to passed dirid */
2012	rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2013	if (args->dirid != btrfs_root_ref_dirid(leaf, rref)) {
2014		ret = -EINVAL;
2015		goto out;
2016	}
2017
2018	/* Copy subvolume's name */
2019	item_off += sizeof(struct btrfs_root_ref);
2020	item_len -= sizeof(struct btrfs_root_ref);
2021	read_extent_buffer(leaf, args->name, item_off, item_len);
2022	args->name[item_len] = 0;
2023
2024out_put:
2025	btrfs_put_root(root);
2026out:
2027	btrfs_free_path(path);
2028	return ret;
2029}
2030
2031static noinline int btrfs_ioctl_ino_lookup(struct btrfs_root *root,
2032					   void __user *argp)
2033{
2034	struct btrfs_ioctl_ino_lookup_args *args;
2035	int ret = 0;
 
 
 
 
2036
2037	args = memdup_user(argp, sizeof(*args));
2038	if (IS_ERR(args))
2039		return PTR_ERR(args);
2040
2041	/*
2042	 * Unprivileged query to obtain the containing subvolume root id. The
2043	 * path is reset so it's consistent with btrfs_search_path_in_tree.
2044	 */
2045	if (args->treeid == 0)
2046		args->treeid = root->root_key.objectid;
2047
2048	if (args->objectid == BTRFS_FIRST_FREE_OBJECTID) {
2049		args->name[0] = 0;
2050		goto out;
2051	}
2052
2053	if (!capable(CAP_SYS_ADMIN)) {
2054		ret = -EPERM;
2055		goto out;
2056	}
2057
2058	ret = btrfs_search_path_in_tree(root->fs_info,
2059					args->treeid, args->objectid,
2060					args->name);
2061
2062out:
2063	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2064		ret = -EFAULT;
2065
2066	kfree(args);
2067	return ret;
2068}
2069
2070/*
2071 * Version of ino_lookup ioctl (unprivileged)
2072 *
2073 * The main differences from ino_lookup ioctl are:
2074 *
2075 *   1. Read + Exec permission will be checked using inode_permission() during
2076 *      path construction. -EACCES will be returned in case of failure.
2077 *   2. Path construction will be stopped at the inode number which corresponds
2078 *      to the fd with which this ioctl is called. If constructed path does not
2079 *      exist under fd's inode, -EACCES will be returned.
2080 *   3. The name of bottom subvolume is also searched and filled.
2081 */
2082static int btrfs_ioctl_ino_lookup_user(struct file *file, void __user *argp)
2083{
2084	struct btrfs_ioctl_ino_lookup_user_args *args;
2085	struct inode *inode;
2086	int ret;
2087
2088	args = memdup_user(argp, sizeof(*args));
2089	if (IS_ERR(args))
2090		return PTR_ERR(args);
2091
2092	inode = file_inode(file);
2093
2094	if (args->dirid == BTRFS_FIRST_FREE_OBJECTID &&
2095	    BTRFS_I(inode)->location.objectid != BTRFS_FIRST_FREE_OBJECTID) {
2096		/*
2097		 * The subvolume does not exist under fd with which this is
2098		 * called
2099		 */
2100		kfree(args);
2101		return -EACCES;
2102	}
2103
2104	ret = btrfs_search_path_in_tree_user(file_mnt_user_ns(file), inode, args);
2105
2106	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
2107		ret = -EFAULT;
2108
2109	kfree(args);
2110	return ret;
2111}
2112
2113/* Get the subvolume information in BTRFS_ROOT_ITEM and BTRFS_ROOT_BACKREF */
2114static int btrfs_ioctl_get_subvol_info(struct inode *inode, void __user *argp)
2115{
2116	struct btrfs_ioctl_get_subvol_info_args *subvol_info;
2117	struct btrfs_fs_info *fs_info;
2118	struct btrfs_root *root;
2119	struct btrfs_path *path;
2120	struct btrfs_key key;
2121	struct btrfs_root_item *root_item;
2122	struct btrfs_root_ref *rref;
2123	struct extent_buffer *leaf;
2124	unsigned long item_off;
2125	unsigned long item_len;
2126	int slot;
2127	int ret = 0;
2128
2129	path = btrfs_alloc_path();
2130	if (!path)
2131		return -ENOMEM;
2132
2133	subvol_info = kzalloc(sizeof(*subvol_info), GFP_KERNEL);
2134	if (!subvol_info) {
2135		btrfs_free_path(path);
2136		return -ENOMEM;
2137	}
2138
2139	fs_info = BTRFS_I(inode)->root->fs_info;
2140
2141	/* Get root_item of inode's subvolume */
2142	key.objectid = BTRFS_I(inode)->root->root_key.objectid;
2143	root = btrfs_get_fs_root(fs_info, key.objectid, true);
2144	if (IS_ERR(root)) {
2145		ret = PTR_ERR(root);
2146		goto out_free;
2147	}
2148	root_item = &root->root_item;
2149
2150	subvol_info->treeid = key.objectid;
2151
2152	subvol_info->generation = btrfs_root_generation(root_item);
2153	subvol_info->flags = btrfs_root_flags(root_item);
2154
2155	memcpy(subvol_info->uuid, root_item->uuid, BTRFS_UUID_SIZE);
2156	memcpy(subvol_info->parent_uuid, root_item->parent_uuid,
2157						    BTRFS_UUID_SIZE);
2158	memcpy(subvol_info->received_uuid, root_item->received_uuid,
2159						    BTRFS_UUID_SIZE);
2160
2161	subvol_info->ctransid = btrfs_root_ctransid(root_item);
2162	subvol_info->ctime.sec = btrfs_stack_timespec_sec(&root_item->ctime);
2163	subvol_info->ctime.nsec = btrfs_stack_timespec_nsec(&root_item->ctime);
2164
2165	subvol_info->otransid = btrfs_root_otransid(root_item);
2166	subvol_info->otime.sec = btrfs_stack_timespec_sec(&root_item->otime);
2167	subvol_info->otime.nsec = btrfs_stack_timespec_nsec(&root_item->otime);
2168
2169	subvol_info->stransid = btrfs_root_stransid(root_item);
2170	subvol_info->stime.sec = btrfs_stack_timespec_sec(&root_item->stime);
2171	subvol_info->stime.nsec = btrfs_stack_timespec_nsec(&root_item->stime);
2172
2173	subvol_info->rtransid = btrfs_root_rtransid(root_item);
2174	subvol_info->rtime.sec = btrfs_stack_timespec_sec(&root_item->rtime);
2175	subvol_info->rtime.nsec = btrfs_stack_timespec_nsec(&root_item->rtime);
2176
2177	if (key.objectid != BTRFS_FS_TREE_OBJECTID) {
2178		/* Search root tree for ROOT_BACKREF of this subvolume */
2179		key.type = BTRFS_ROOT_BACKREF_KEY;
2180		key.offset = 0;
2181		ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
2182		if (ret < 0) {
2183			goto out;
2184		} else if (path->slots[0] >=
2185			   btrfs_header_nritems(path->nodes[0])) {
2186			ret = btrfs_next_leaf(fs_info->tree_root, path);
2187			if (ret < 0) {
2188				goto out;
2189			} else if (ret > 0) {
2190				ret = -EUCLEAN;
2191				goto out;
2192			}
2193		}
2194
2195		leaf = path->nodes[0];
2196		slot = path->slots[0];
2197		btrfs_item_key_to_cpu(leaf, &key, slot);
2198		if (key.objectid == subvol_info->treeid &&
2199		    key.type == BTRFS_ROOT_BACKREF_KEY) {
2200			subvol_info->parent_id = key.offset;
2201
2202			rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2203			subvol_info->dirid = btrfs_root_ref_dirid(leaf, rref);
2204
2205			item_off = btrfs_item_ptr_offset(leaf, slot)
2206					+ sizeof(struct btrfs_root_ref);
2207			item_len = btrfs_item_size(leaf, slot)
2208					- sizeof(struct btrfs_root_ref);
2209			read_extent_buffer(leaf, subvol_info->name,
2210					   item_off, item_len);
2211		} else {
2212			ret = -ENOENT;
2213			goto out;
2214		}
2215	}
2216
2217	btrfs_free_path(path);
2218	path = NULL;
2219	if (copy_to_user(argp, subvol_info, sizeof(*subvol_info)))
2220		ret = -EFAULT;
2221
2222out:
2223	btrfs_put_root(root);
2224out_free:
2225	btrfs_free_path(path);
2226	kfree(subvol_info);
2227	return ret;
2228}
2229
2230/*
2231 * Return ROOT_REF information of the subvolume containing this inode
2232 * except the subvolume name.
2233 */
2234static int btrfs_ioctl_get_subvol_rootref(struct btrfs_root *root,
2235					  void __user *argp)
2236{
2237	struct btrfs_ioctl_get_subvol_rootref_args *rootrefs;
2238	struct btrfs_root_ref *rref;
2239	struct btrfs_path *path;
2240	struct btrfs_key key;
2241	struct extent_buffer *leaf;
2242	u64 objectid;
2243	int slot;
2244	int ret;
2245	u8 found;
2246
2247	path = btrfs_alloc_path();
2248	if (!path)
2249		return -ENOMEM;
2250
2251	rootrefs = memdup_user(argp, sizeof(*rootrefs));
2252	if (IS_ERR(rootrefs)) {
2253		btrfs_free_path(path);
2254		return PTR_ERR(rootrefs);
2255	}
2256
2257	objectid = root->root_key.objectid;
2258	key.objectid = objectid;
2259	key.type = BTRFS_ROOT_REF_KEY;
2260	key.offset = rootrefs->min_treeid;
2261	found = 0;
2262
2263	root = root->fs_info->tree_root;
2264	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2265	if (ret < 0) {
2266		goto out;
2267	} else if (path->slots[0] >=
2268		   btrfs_header_nritems(path->nodes[0])) {
2269		ret = btrfs_next_leaf(root, path);
2270		if (ret < 0) {
2271			goto out;
2272		} else if (ret > 0) {
2273			ret = -EUCLEAN;
2274			goto out;
2275		}
2276	}
2277	while (1) {
2278		leaf = path->nodes[0];
2279		slot = path->slots[0];
2280
2281		btrfs_item_key_to_cpu(leaf, &key, slot);
2282		if (key.objectid != objectid || key.type != BTRFS_ROOT_REF_KEY) {
2283			ret = 0;
2284			goto out;
2285		}
2286
2287		if (found == BTRFS_MAX_ROOTREF_BUFFER_NUM) {
2288			ret = -EOVERFLOW;
2289			goto out;
2290		}
2291
2292		rref = btrfs_item_ptr(leaf, slot, struct btrfs_root_ref);
2293		rootrefs->rootref[found].treeid = key.offset;
2294		rootrefs->rootref[found].dirid =
2295				  btrfs_root_ref_dirid(leaf, rref);
2296		found++;
2297
2298		ret = btrfs_next_item(root, path);
2299		if (ret < 0) {
2300			goto out;
2301		} else if (ret > 0) {
2302			ret = -EUCLEAN;
2303			goto out;
2304		}
2305	}
2306
2307out:
2308	btrfs_free_path(path);
2309
2310	if (!ret || ret == -EOVERFLOW) {
2311		rootrefs->num_items = found;
2312		/* update min_treeid for next search */
2313		if (found)
2314			rootrefs->min_treeid =
2315				rootrefs->rootref[found - 1].treeid + 1;
2316		if (copy_to_user(argp, rootrefs, sizeof(*rootrefs)))
2317			ret = -EFAULT;
2318	}
2319
2320	kfree(rootrefs);
2321
2322	return ret;
2323}
2324
2325static noinline int btrfs_ioctl_snap_destroy(struct file *file,
2326					     void __user *arg,
2327					     bool destroy_v2)
2328{
2329	struct dentry *parent = file->f_path.dentry;
2330	struct btrfs_fs_info *fs_info = btrfs_sb(parent->d_sb);
2331	struct dentry *dentry;
2332	struct inode *dir = d_inode(parent);
2333	struct inode *inode;
2334	struct btrfs_root *root = BTRFS_I(dir)->root;
2335	struct btrfs_root *dest = NULL;
2336	struct btrfs_ioctl_vol_args *vol_args = NULL;
2337	struct btrfs_ioctl_vol_args_v2 *vol_args2 = NULL;
2338	struct user_namespace *mnt_userns = file_mnt_user_ns(file);
2339	char *subvol_name, *subvol_name_ptr = NULL;
2340	int subvol_namelen;
2341	int err = 0;
2342	bool destroy_parent = false;
2343
2344	/* We don't support snapshots with extent tree v2 yet. */
2345	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
2346		btrfs_err(fs_info,
2347			  "extent tree v2 doesn't support snapshot deletion yet");
2348		return -EOPNOTSUPP;
2349	}
2350
2351	if (destroy_v2) {
2352		vol_args2 = memdup_user(arg, sizeof(*vol_args2));
2353		if (IS_ERR(vol_args2))
2354			return PTR_ERR(vol_args2);
2355
2356		if (vol_args2->flags & ~BTRFS_SUBVOL_DELETE_ARGS_MASK) {
2357			err = -EOPNOTSUPP;
2358			goto out;
2359		}
2360
2361		/*
2362		 * If SPEC_BY_ID is not set, we are looking for the subvolume by
2363		 * name, same as v1 currently does.
2364		 */
2365		if (!(vol_args2->flags & BTRFS_SUBVOL_SPEC_BY_ID)) {
2366			vol_args2->name[BTRFS_SUBVOL_NAME_MAX] = 0;
2367			subvol_name = vol_args2->name;
2368
2369			err = mnt_want_write_file(file);
2370			if (err)
2371				goto out;
2372		} else {
2373			struct inode *old_dir;
2374
2375			if (vol_args2->subvolid < BTRFS_FIRST_FREE_OBJECTID) {
2376				err = -EINVAL;
2377				goto out;
2378			}
2379
2380			err = mnt_want_write_file(file);
2381			if (err)
2382				goto out;
2383
2384			dentry = btrfs_get_dentry(fs_info->sb,
2385					BTRFS_FIRST_FREE_OBJECTID,
2386					vol_args2->subvolid, 0);
2387			if (IS_ERR(dentry)) {
2388				err = PTR_ERR(dentry);
2389				goto out_drop_write;
2390			}
2391
2392			/*
2393			 * Change the default parent since the subvolume being
2394			 * deleted can be outside of the current mount point.
2395			 */
2396			parent = btrfs_get_parent(dentry);
2397
2398			/*
2399			 * At this point dentry->d_name can point to '/' if the
2400			 * subvolume we want to destroy is outsite of the
2401			 * current mount point, so we need to release the
2402			 * current dentry and execute the lookup to return a new
2403			 * one with ->d_name pointing to the
2404			 * <mount point>/subvol_name.
2405			 */
2406			dput(dentry);
2407			if (IS_ERR(parent)) {
2408				err = PTR_ERR(parent);
2409				goto out_drop_write;
2410			}
2411			old_dir = dir;
2412			dir = d_inode(parent);
2413
2414			/*
2415			 * If v2 was used with SPEC_BY_ID, a new parent was
2416			 * allocated since the subvolume can be outside of the
2417			 * current mount point. Later on we need to release this
2418			 * new parent dentry.
2419			 */
2420			destroy_parent = true;
2421
2422			/*
2423			 * On idmapped mounts, deletion via subvolid is
2424			 * restricted to subvolumes that are immediate
2425			 * ancestors of the inode referenced by the file
2426			 * descriptor in the ioctl. Otherwise the idmapping
2427			 * could potentially be abused to delete subvolumes
2428			 * anywhere in the filesystem the user wouldn't be able
2429			 * to delete without an idmapped mount.
2430			 */
2431			if (old_dir != dir && mnt_userns != &init_user_ns) {
2432				err = -EOPNOTSUPP;
2433				goto free_parent;
2434			}
2435
2436			subvol_name_ptr = btrfs_get_subvol_name_from_objectid(
2437						fs_info, vol_args2->subvolid);
2438			if (IS_ERR(subvol_name_ptr)) {
2439				err = PTR_ERR(subvol_name_ptr);
2440				goto free_parent;
2441			}
2442			/* subvol_name_ptr is already nul terminated */
2443			subvol_name = (char *)kbasename(subvol_name_ptr);
2444		}
2445	} else {
2446		vol_args = memdup_user(arg, sizeof(*vol_args));
2447		if (IS_ERR(vol_args))
2448			return PTR_ERR(vol_args);
2449
2450		vol_args->name[BTRFS_PATH_NAME_MAX] = 0;
2451		subvol_name = vol_args->name;
2452
2453		err = mnt_want_write_file(file);
2454		if (err)
2455			goto out;
2456	}
2457
2458	subvol_namelen = strlen(subvol_name);
2459
2460	if (strchr(subvol_name, '/') ||
2461	    strncmp(subvol_name, "..", subvol_namelen) == 0) {
 
 
2462		err = -EINVAL;
2463		goto free_subvol_name;
2464	}
2465
2466	if (!S_ISDIR(dir->i_mode)) {
2467		err = -ENOTDIR;
2468		goto free_subvol_name;
2469	}
2470
2471	err = down_write_killable_nested(&dir->i_rwsem, I_MUTEX_PARENT);
2472	if (err == -EINTR)
2473		goto free_subvol_name;
2474	dentry = lookup_one(mnt_userns, subvol_name, parent, subvol_namelen);
2475	if (IS_ERR(dentry)) {
2476		err = PTR_ERR(dentry);
2477		goto out_unlock_dir;
2478	}
2479
2480	if (d_really_is_negative(dentry)) {
2481		err = -ENOENT;
2482		goto out_dput;
2483	}
2484
2485	inode = d_inode(dentry);
2486	dest = BTRFS_I(inode)->root;
2487	if (!capable(CAP_SYS_ADMIN)) {
2488		/*
2489		 * Regular user.  Only allow this with a special mount
2490		 * option, when the user has write+exec access to the
2491		 * subvol root, and when rmdir(2) would have been
2492		 * allowed.
2493		 *
2494		 * Note that this is _not_ check that the subvol is
2495		 * empty or doesn't contain data that we wouldn't
2496		 * otherwise be able to delete.
2497		 *
2498		 * Users who want to delete empty subvols should try
2499		 * rmdir(2).
2500		 */
2501		err = -EPERM;
2502		if (!btrfs_test_opt(fs_info, USER_SUBVOL_RM_ALLOWED))
2503			goto out_dput;
2504
2505		/*
2506		 * Do not allow deletion if the parent dir is the same
2507		 * as the dir to be deleted.  That means the ioctl
2508		 * must be called on the dentry referencing the root
2509		 * of the subvol, not a random directory contained
2510		 * within it.
2511		 */
2512		err = -EINVAL;
2513		if (root == dest)
2514			goto out_dput;
2515
2516		err = inode_permission(mnt_userns, inode, MAY_WRITE | MAY_EXEC);
2517		if (err)
2518			goto out_dput;
2519	}
2520
2521	/* check if subvolume may be deleted by a user */
2522	err = btrfs_may_delete(mnt_userns, dir, dentry, 1);
2523	if (err)
2524		goto out_dput;
 
2525
2526	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
2527		err = -EINVAL;
2528		goto out_dput;
2529	}
2530
2531	btrfs_inode_lock(BTRFS_I(inode), 0);
2532	err = btrfs_delete_subvolume(BTRFS_I(dir), dentry);
2533	btrfs_inode_unlock(BTRFS_I(inode), 0);
2534	if (!err)
2535		d_delete_notify(dir, dentry);
 
 
 
 
 
 
 
 
 
 
 
 
2536
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2537out_dput:
2538	dput(dentry);
2539out_unlock_dir:
2540	btrfs_inode_unlock(BTRFS_I(dir), 0);
2541free_subvol_name:
2542	kfree(subvol_name_ptr);
2543free_parent:
2544	if (destroy_parent)
2545		dput(parent);
2546out_drop_write:
2547	mnt_drop_write_file(file);
2548out:
2549	kfree(vol_args2);
2550	kfree(vol_args);
2551	return err;
2552}
2553
2554static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2555{
2556	struct inode *inode = file_inode(file);
2557	struct btrfs_root *root = BTRFS_I(inode)->root;
2558	struct btrfs_ioctl_defrag_range_args range = {0};
2559	int ret;
2560
 
 
 
2561	ret = mnt_want_write_file(file);
2562	if (ret)
2563		return ret;
2564
2565	if (btrfs_root_readonly(root)) {
2566		ret = -EROFS;
2567		goto out;
2568	}
2569
2570	switch (inode->i_mode & S_IFMT) {
2571	case S_IFDIR:
2572		if (!capable(CAP_SYS_ADMIN)) {
2573			ret = -EPERM;
2574			goto out;
2575		}
2576		ret = btrfs_defrag_root(root);
 
 
 
2577		break;
2578	case S_IFREG:
2579		/*
2580		 * Note that this does not check the file descriptor for write
2581		 * access. This prevents defragmenting executables that are
2582		 * running and allows defrag on files open in read-only mode.
2583		 */
2584		if (!capable(CAP_SYS_ADMIN) &&
2585		    inode_permission(&init_user_ns, inode, MAY_WRITE)) {
2586			ret = -EPERM;
2587			goto out;
2588		}
2589
2590		if (argp) {
2591			if (copy_from_user(&range, argp, sizeof(range))) {
 
2592				ret = -EFAULT;
 
2593				goto out;
2594			}
2595			/* compression requires us to start the IO */
2596			if ((range.flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2597				range.flags |= BTRFS_DEFRAG_RANGE_START_IO;
2598				range.extent_thresh = (u32)-1;
2599			}
2600		} else {
2601			/* the rest are all set to zero by kzalloc */
2602			range.len = (u64)-1;
2603		}
2604		ret = btrfs_defrag_file(file_inode(file), &file->f_ra,
2605					&range, BTRFS_OLDEST_GENERATION, 0);
2606		if (ret > 0)
2607			ret = 0;
 
2608		break;
2609	default:
2610		ret = -EINVAL;
2611	}
2612out:
2613	mnt_drop_write_file(file);
2614	return ret;
2615}
2616
2617static long btrfs_ioctl_add_dev(struct btrfs_fs_info *fs_info, void __user *arg)
2618{
2619	struct btrfs_ioctl_vol_args *vol_args;
2620	bool restore_op = false;
2621	int ret;
2622
2623	if (!capable(CAP_SYS_ADMIN))
2624		return -EPERM;
2625
2626	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
2627		btrfs_err(fs_info, "device add not supported on extent tree v2 yet");
2628		return -EINVAL;
2629	}
2630
2631	if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_ADD)) {
2632		if (!btrfs_exclop_start_try_lock(fs_info, BTRFS_EXCLOP_DEV_ADD))
2633			return BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
2634
2635		/*
2636		 * We can do the device add because we have a paused balanced,
2637		 * change the exclusive op type and remember we should bring
2638		 * back the paused balance
2639		 */
2640		fs_info->exclusive_operation = BTRFS_EXCLOP_DEV_ADD;
2641		btrfs_exclop_start_unlock(fs_info);
2642		restore_op = true;
2643	}
2644
2645	vol_args = memdup_user(arg, sizeof(*vol_args));
2646	if (IS_ERR(vol_args)) {
2647		ret = PTR_ERR(vol_args);
2648		goto out;
2649	}
2650
2651	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2652	ret = btrfs_init_new_device(fs_info, vol_args->name);
2653
2654	if (!ret)
2655		btrfs_info(fs_info, "disk added %s", vol_args->name);
2656
2657	kfree(vol_args);
2658out:
2659	if (restore_op)
2660		btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE_PAUSED);
2661	else
2662		btrfs_exclop_finish(fs_info);
2663	return ret;
2664}
2665
2666static long btrfs_ioctl_rm_dev_v2(struct file *file, void __user *arg)
2667{
2668	BTRFS_DEV_LOOKUP_ARGS(args);
2669	struct inode *inode = file_inode(file);
2670	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2671	struct btrfs_ioctl_vol_args_v2 *vol_args;
2672	struct block_device *bdev = NULL;
2673	fmode_t mode;
2674	int ret;
2675	bool cancel = false;
2676
2677	if (!capable(CAP_SYS_ADMIN))
2678		return -EPERM;
2679
2680	vol_args = memdup_user(arg, sizeof(*vol_args));
2681	if (IS_ERR(vol_args))
2682		return PTR_ERR(vol_args);
2683
2684	if (vol_args->flags & ~BTRFS_DEVICE_REMOVE_ARGS_MASK) {
2685		ret = -EOPNOTSUPP;
 
 
2686		goto out;
2687	}
2688
2689	vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
2690	if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID) {
2691		args.devid = vol_args->devid;
2692	} else if (!strcmp("cancel", vol_args->name)) {
2693		cancel = true;
2694	} else {
2695		ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
2696		if (ret)
2697			goto out;
2698	}
2699
2700	ret = mnt_want_write_file(file);
2701	if (ret)
2702		goto out;
2703
2704	ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
2705					   cancel);
2706	if (ret)
2707		goto err_drop;
2708
2709	/* Exclusive operation is now claimed */
2710	ret = btrfs_rm_device(fs_info, &args, &bdev, &mode);
2711
2712	btrfs_exclop_finish(fs_info);
2713
2714	if (!ret) {
2715		if (vol_args->flags & BTRFS_DEVICE_SPEC_BY_ID)
2716			btrfs_info(fs_info, "device deleted: id %llu",
2717					vol_args->devid);
2718		else
2719			btrfs_info(fs_info, "device deleted: %s",
2720					vol_args->name);
2721	}
2722err_drop:
2723	mnt_drop_write_file(file);
2724	if (bdev)
2725		blkdev_put(bdev, mode);
2726out:
2727	btrfs_put_dev_args_from_path(&args);
2728	kfree(vol_args);
2729	return ret;
2730}
2731
2732static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
2733{
2734	BTRFS_DEV_LOOKUP_ARGS(args);
2735	struct inode *inode = file_inode(file);
2736	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2737	struct btrfs_ioctl_vol_args *vol_args;
2738	struct block_device *bdev = NULL;
2739	fmode_t mode;
2740	int ret;
2741	bool cancel = false;
2742
2743	if (!capable(CAP_SYS_ADMIN))
2744		return -EPERM;
2745
2746	vol_args = memdup_user(arg, sizeof(*vol_args));
2747	if (IS_ERR(vol_args))
2748		return PTR_ERR(vol_args);
2749
2750	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2751	if (!strcmp("cancel", vol_args->name)) {
2752		cancel = true;
2753	} else {
2754		ret = btrfs_get_dev_args_from_path(fs_info, &args, vol_args->name);
2755		if (ret)
2756			goto out;
2757	}
2758
2759	ret = mnt_want_write_file(file);
2760	if (ret)
2761		goto out;
2762
2763	ret = exclop_start_or_cancel_reloc(fs_info, BTRFS_EXCLOP_DEV_REMOVE,
2764					   cancel);
2765	if (ret == 0) {
2766		ret = btrfs_rm_device(fs_info, &args, &bdev, &mode);
2767		if (!ret)
2768			btrfs_info(fs_info, "disk deleted %s", vol_args->name);
2769		btrfs_exclop_finish(fs_info);
2770	}
2771
2772	mnt_drop_write_file(file);
2773	if (bdev)
2774		blkdev_put(bdev, mode);
2775out:
2776	btrfs_put_dev_args_from_path(&args);
2777	kfree(vol_args);
 
 
2778	return ret;
2779}
2780
2781static long btrfs_ioctl_fs_info(struct btrfs_fs_info *fs_info,
2782				void __user *arg)
2783{
2784	struct btrfs_ioctl_fs_info_args *fi_args;
2785	struct btrfs_device *device;
2786	struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
2787	u64 flags_in;
2788	int ret = 0;
2789
2790	fi_args = memdup_user(arg, sizeof(*fi_args));
2791	if (IS_ERR(fi_args))
2792		return PTR_ERR(fi_args);
2793
2794	flags_in = fi_args->flags;
2795	memset(fi_args, 0, sizeof(*fi_args));
 
2796
2797	rcu_read_lock();
2798	fi_args->num_devices = fs_devices->num_devices;
 
2799
2800	list_for_each_entry_rcu(device, &fs_devices->devices, dev_list) {
 
2801		if (device->devid > fi_args->max_id)
2802			fi_args->max_id = device->devid;
2803	}
2804	rcu_read_unlock();
2805
2806	memcpy(&fi_args->fsid, fs_devices->fsid, sizeof(fi_args->fsid));
2807	fi_args->nodesize = fs_info->nodesize;
2808	fi_args->sectorsize = fs_info->sectorsize;
2809	fi_args->clone_alignment = fs_info->sectorsize;
2810
2811	if (flags_in & BTRFS_FS_INFO_FLAG_CSUM_INFO) {
2812		fi_args->csum_type = btrfs_super_csum_type(fs_info->super_copy);
2813		fi_args->csum_size = btrfs_super_csum_size(fs_info->super_copy);
2814		fi_args->flags |= BTRFS_FS_INFO_FLAG_CSUM_INFO;
2815	}
2816
2817	if (flags_in & BTRFS_FS_INFO_FLAG_GENERATION) {
2818		fi_args->generation = fs_info->generation;
2819		fi_args->flags |= BTRFS_FS_INFO_FLAG_GENERATION;
2820	}
2821
2822	if (flags_in & BTRFS_FS_INFO_FLAG_METADATA_UUID) {
2823		memcpy(&fi_args->metadata_uuid, fs_devices->metadata_uuid,
2824		       sizeof(fi_args->metadata_uuid));
2825		fi_args->flags |= BTRFS_FS_INFO_FLAG_METADATA_UUID;
2826	}
2827
2828	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2829		ret = -EFAULT;
2830
2831	kfree(fi_args);
2832	return ret;
2833}
2834
2835static long btrfs_ioctl_dev_info(struct btrfs_fs_info *fs_info,
2836				 void __user *arg)
2837{
2838	BTRFS_DEV_LOOKUP_ARGS(args);
2839	struct btrfs_ioctl_dev_info_args *di_args;
2840	struct btrfs_device *dev;
 
2841	int ret = 0;
 
 
 
 
 
2842
2843	di_args = memdup_user(arg, sizeof(*di_args));
2844	if (IS_ERR(di_args))
2845		return PTR_ERR(di_args);
2846
2847	args.devid = di_args->devid;
2848	if (!btrfs_is_empty_uuid(di_args->uuid))
2849		args.uuid = di_args->uuid;
 
 
 
2850
2851	rcu_read_lock();
2852	dev = btrfs_find_device(fs_info->fs_devices, &args);
2853	if (!dev) {
2854		ret = -ENODEV;
2855		goto out;
2856	}
2857
2858	di_args->devid = dev->devid;
2859	di_args->bytes_used = btrfs_device_get_bytes_used(dev);
2860	di_args->total_bytes = btrfs_device_get_total_bytes(dev);
2861	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2862	if (dev->name)
2863		strscpy(di_args->path, btrfs_dev_name(dev), sizeof(di_args->path));
2864	else
 
 
 
 
 
 
2865		di_args->path[0] = '\0';
 
2866
2867out:
2868	rcu_read_unlock();
2869	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2870		ret = -EFAULT;
2871
2872	kfree(di_args);
2873	return ret;
2874}
2875
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2876static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2877{
2878	struct inode *inode = file_inode(file);
2879	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
2880	struct btrfs_root *root = BTRFS_I(inode)->root;
2881	struct btrfs_root *new_root;
2882	struct btrfs_dir_item *di;
2883	struct btrfs_trans_handle *trans;
2884	struct btrfs_path *path = NULL;
 
2885	struct btrfs_disk_key disk_key;
2886	struct fscrypt_str name = FSTR_INIT("default", 7);
 
2887	u64 objectid = 0;
2888	u64 dir_id;
2889	int ret;
2890
2891	if (!capable(CAP_SYS_ADMIN))
2892		return -EPERM;
2893
2894	ret = mnt_want_write_file(file);
2895	if (ret)
2896		return ret;
2897
2898	if (copy_from_user(&objectid, argp, sizeof(objectid))) {
2899		ret = -EFAULT;
2900		goto out;
2901	}
2902
2903	if (!objectid)
2904		objectid = BTRFS_FS_TREE_OBJECTID;
2905
2906	new_root = btrfs_get_fs_root(fs_info, objectid, true);
2907	if (IS_ERR(new_root)) {
2908		ret = PTR_ERR(new_root);
2909		goto out;
2910	}
2911	if (!is_fstree(new_root->root_key.objectid)) {
2912		ret = -ENOENT;
2913		goto out_free;
2914	}
 
2915
2916	path = btrfs_alloc_path();
2917	if (!path) {
2918		ret = -ENOMEM;
2919		goto out_free;
2920	}
2921
2922	trans = btrfs_start_transaction(root, 1);
2923	if (IS_ERR(trans)) {
2924		ret = PTR_ERR(trans);
2925		goto out_free;
2926	}
2927
2928	dir_id = btrfs_super_root_dir(fs_info->super_copy);
2929	di = btrfs_lookup_dir_item(trans, fs_info->tree_root, path,
2930				   dir_id, &name, 1);
2931	if (IS_ERR_OR_NULL(di)) {
2932		btrfs_release_path(path);
2933		btrfs_end_transaction(trans);
2934		btrfs_err(fs_info,
2935			  "Umm, you don't have the default diritem, this isn't going to work");
2936		ret = -ENOENT;
2937		goto out_free;
2938	}
2939
2940	btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2941	btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2942	btrfs_mark_buffer_dirty(path->nodes[0]);
2943	btrfs_release_path(path);
2944
2945	btrfs_set_fs_incompat(fs_info, DEFAULT_SUBVOL);
2946	btrfs_end_transaction(trans);
2947out_free:
2948	btrfs_put_root(new_root);
2949	btrfs_free_path(path);
2950out:
2951	mnt_drop_write_file(file);
2952	return ret;
 
 
 
 
 
 
 
2953}
2954
2955static void get_block_group_info(struct list_head *groups_list,
2956				 struct btrfs_ioctl_space_info *space)
2957{
2958	struct btrfs_block_group *block_group;
2959
2960	space->total_bytes = 0;
2961	space->used_bytes = 0;
2962	space->flags = 0;
2963	list_for_each_entry(block_group, groups_list, list) {
2964		space->flags = block_group->flags;
2965		space->total_bytes += block_group->length;
2966		space->used_bytes += block_group->used;
 
2967	}
2968}
2969
2970static long btrfs_ioctl_space_info(struct btrfs_fs_info *fs_info,
2971				   void __user *arg)
2972{
2973	struct btrfs_ioctl_space_args space_args;
2974	struct btrfs_ioctl_space_info space;
2975	struct btrfs_ioctl_space_info *dest;
2976	struct btrfs_ioctl_space_info *dest_orig;
2977	struct btrfs_ioctl_space_info __user *user_dest;
2978	struct btrfs_space_info *info;
2979	static const u64 types[] = {
2980		BTRFS_BLOCK_GROUP_DATA,
2981		BTRFS_BLOCK_GROUP_SYSTEM,
2982		BTRFS_BLOCK_GROUP_METADATA,
2983		BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA
2984	};
2985	int num_types = 4;
2986	int alloc_size;
2987	int ret = 0;
2988	u64 slot_count = 0;
2989	int i, c;
2990
2991	if (copy_from_user(&space_args,
2992			   (struct btrfs_ioctl_space_args __user *)arg,
2993			   sizeof(space_args)))
2994		return -EFAULT;
2995
2996	for (i = 0; i < num_types; i++) {
2997		struct btrfs_space_info *tmp;
2998
2999		info = NULL;
3000		list_for_each_entry(tmp, &fs_info->space_info, list) {
 
 
3001			if (tmp->flags == types[i]) {
3002				info = tmp;
3003				break;
3004			}
3005		}
 
3006
3007		if (!info)
3008			continue;
3009
3010		down_read(&info->groups_sem);
3011		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3012			if (!list_empty(&info->block_groups[c]))
3013				slot_count++;
3014		}
3015		up_read(&info->groups_sem);
3016	}
3017
3018	/*
3019	 * Global block reserve, exported as a space_info
3020	 */
3021	slot_count++;
3022
3023	/* space_slots == 0 means they are asking for a count */
3024	if (space_args.space_slots == 0) {
3025		space_args.total_spaces = slot_count;
3026		goto out;
3027	}
3028
3029	slot_count = min_t(u64, space_args.space_slots, slot_count);
3030
3031	alloc_size = sizeof(*dest) * slot_count;
3032
3033	/* we generally have at most 6 or so space infos, one for each raid
3034	 * level.  So, a whole page should be more than enough for everyone
3035	 */
3036	if (alloc_size > PAGE_SIZE)
3037		return -ENOMEM;
3038
3039	space_args.total_spaces = 0;
3040	dest = kmalloc(alloc_size, GFP_KERNEL);
3041	if (!dest)
3042		return -ENOMEM;
3043	dest_orig = dest;
3044
3045	/* now we have a buffer to copy into */
3046	for (i = 0; i < num_types; i++) {
3047		struct btrfs_space_info *tmp;
3048
3049		if (!slot_count)
3050			break;
3051
3052		info = NULL;
3053		list_for_each_entry(tmp, &fs_info->space_info, list) {
 
 
3054			if (tmp->flags == types[i]) {
3055				info = tmp;
3056				break;
3057			}
3058		}
 
3059
3060		if (!info)
3061			continue;
3062		down_read(&info->groups_sem);
3063		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
3064			if (!list_empty(&info->block_groups[c])) {
3065				get_block_group_info(&info->block_groups[c],
3066						     &space);
3067				memcpy(dest, &space, sizeof(space));
3068				dest++;
3069				space_args.total_spaces++;
3070				slot_count--;
3071			}
3072			if (!slot_count)
3073				break;
3074		}
3075		up_read(&info->groups_sem);
3076	}
3077
3078	/*
3079	 * Add global block reserve
3080	 */
3081	if (slot_count) {
3082		struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
3083
3084		spin_lock(&block_rsv->lock);
3085		space.total_bytes = block_rsv->size;
3086		space.used_bytes = block_rsv->size - block_rsv->reserved;
3087		spin_unlock(&block_rsv->lock);
3088		space.flags = BTRFS_SPACE_INFO_GLOBAL_RSV;
3089		memcpy(dest, &space, sizeof(space));
3090		space_args.total_spaces++;
3091	}
3092
3093	user_dest = (struct btrfs_ioctl_space_info __user *)
3094		(arg + sizeof(struct btrfs_ioctl_space_args));
3095
3096	if (copy_to_user(user_dest, dest_orig, alloc_size))
3097		ret = -EFAULT;
3098
3099	kfree(dest_orig);
3100out:
3101	if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
3102		ret = -EFAULT;
3103
3104	return ret;
3105}
3106
3107static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
3108					    void __user *argp)
 
 
 
 
 
3109{
 
 
3110	struct btrfs_trans_handle *trans;
3111	u64 transid;
3112
3113	trans = btrfs_attach_transaction_barrier(root);
3114	if (IS_ERR(trans)) {
3115		if (PTR_ERR(trans) != -ENOENT)
3116			return PTR_ERR(trans);
3117
3118		/* No running transaction, don't bother */
3119		transid = root->fs_info->last_trans_committed;
3120		goto out;
3121	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3122	transid = trans->transid;
3123	btrfs_commit_transaction_async(trans);
3124out:
 
 
 
 
3125	if (argp)
3126		if (copy_to_user(argp, &transid, sizeof(transid)))
3127			return -EFAULT;
3128	return 0;
3129}
3130
3131static noinline long btrfs_ioctl_wait_sync(struct btrfs_fs_info *fs_info,
3132					   void __user *argp)
3133{
 
3134	u64 transid;
3135
3136	if (argp) {
3137		if (copy_from_user(&transid, argp, sizeof(transid)))
3138			return -EFAULT;
3139	} else {
3140		transid = 0;  /* current trans */
3141	}
3142	return btrfs_wait_for_commit(fs_info, transid);
3143}
3144
3145static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
3146{
3147	struct btrfs_fs_info *fs_info = btrfs_sb(file_inode(file)->i_sb);
3148	struct btrfs_ioctl_scrub_args *sa;
3149	int ret;
 
3150
3151	if (!capable(CAP_SYS_ADMIN))
3152		return -EPERM;
3153
3154	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3155		btrfs_err(fs_info, "scrub is not supported on extent tree v2 yet");
3156		return -EINVAL;
3157	}
3158
3159	sa = memdup_user(arg, sizeof(*sa));
3160	if (IS_ERR(sa))
3161		return PTR_ERR(sa);
3162
3163	if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
3164		ret = mnt_want_write_file(file);
3165		if (ret)
3166			goto out;
3167	}
3168
3169	ret = btrfs_scrub_dev(fs_info, sa->devid, sa->start, sa->end,
3170			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
3171			      0);
3172
3173	/*
3174	 * Copy scrub args to user space even if btrfs_scrub_dev() returned an
3175	 * error. This is important as it allows user space to know how much
3176	 * progress scrub has done. For example, if scrub is canceled we get
3177	 * -ECANCELED from btrfs_scrub_dev() and return that error back to user
3178	 * space. Later user space can inspect the progress from the structure
3179	 * btrfs_ioctl_scrub_args and resume scrub from where it left off
3180	 * previously (btrfs-progs does this).
3181	 * If we fail to copy the btrfs_ioctl_scrub_args structure to user space
3182	 * then return -EFAULT to signal the structure was not copied or it may
3183	 * be corrupt and unreliable due to a partial copy.
3184	 */
3185	if (copy_to_user(arg, sa, sizeof(*sa)))
3186		ret = -EFAULT;
3187
3188	if (!(sa->flags & BTRFS_SCRUB_READONLY))
3189		mnt_drop_write_file(file);
3190out:
3191	kfree(sa);
3192	return ret;
3193}
3194
3195static long btrfs_ioctl_scrub_cancel(struct btrfs_fs_info *fs_info)
3196{
3197	if (!capable(CAP_SYS_ADMIN))
3198		return -EPERM;
3199
3200	return btrfs_scrub_cancel(fs_info);
3201}
3202
3203static long btrfs_ioctl_scrub_progress(struct btrfs_fs_info *fs_info,
3204				       void __user *arg)
3205{
3206	struct btrfs_ioctl_scrub_args *sa;
3207	int ret;
3208
3209	if (!capable(CAP_SYS_ADMIN))
3210		return -EPERM;
3211
3212	sa = memdup_user(arg, sizeof(*sa));
3213	if (IS_ERR(sa))
3214		return PTR_ERR(sa);
3215
3216	ret = btrfs_scrub_progress(fs_info, sa->devid, &sa->progress);
3217
3218	if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3219		ret = -EFAULT;
3220
3221	kfree(sa);
3222	return ret;
3223}
3224
3225static long btrfs_ioctl_get_dev_stats(struct btrfs_fs_info *fs_info,
3226				      void __user *arg)
3227{
3228	struct btrfs_ioctl_get_dev_stats *sa;
3229	int ret;
3230
 
 
 
3231	sa = memdup_user(arg, sizeof(*sa));
3232	if (IS_ERR(sa))
3233		return PTR_ERR(sa);
3234
3235	if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
3236		kfree(sa);
3237		return -EPERM;
3238	}
3239
3240	ret = btrfs_get_dev_stats(fs_info, sa);
3241
3242	if (ret == 0 && copy_to_user(arg, sa, sizeof(*sa)))
3243		ret = -EFAULT;
3244
3245	kfree(sa);
3246	return ret;
3247}
3248
3249static long btrfs_ioctl_dev_replace(struct btrfs_fs_info *fs_info,
3250				    void __user *arg)
3251{
3252	struct btrfs_ioctl_dev_replace_args *p;
3253	int ret;
3254
3255	if (!capable(CAP_SYS_ADMIN))
3256		return -EPERM;
3257
3258	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2)) {
3259		btrfs_err(fs_info, "device replace not supported on extent tree v2 yet");
3260		return -EINVAL;
3261	}
3262
3263	p = memdup_user(arg, sizeof(*p));
3264	if (IS_ERR(p))
3265		return PTR_ERR(p);
3266
3267	switch (p->cmd) {
3268	case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3269		if (sb_rdonly(fs_info->sb)) {
3270			ret = -EROFS;
3271			goto out;
3272		}
3273		if (!btrfs_exclop_start(fs_info, BTRFS_EXCLOP_DEV_REPLACE)) {
3274			ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3275		} else {
3276			ret = btrfs_dev_replace_by_ioctl(fs_info, p);
3277			btrfs_exclop_finish(fs_info);
3278		}
3279		break;
3280	case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
3281		btrfs_dev_replace_status(fs_info, p);
3282		ret = 0;
3283		break;
3284	case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
3285		p->result = btrfs_dev_replace_cancel(fs_info);
3286		ret = 0;
3287		break;
3288	default:
3289		ret = -EINVAL;
3290		break;
3291	}
3292
3293	if ((ret == 0 || ret == -ECANCELED) && copy_to_user(arg, p, sizeof(*p)))
3294		ret = -EFAULT;
3295out:
3296	kfree(p);
3297	return ret;
3298}
3299
3300static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3301{
3302	int ret = 0;
3303	int i;
3304	u64 rel_ptr;
3305	int size;
3306	struct btrfs_ioctl_ino_path_args *ipa = NULL;
3307	struct inode_fs_paths *ipath = NULL;
3308	struct btrfs_path *path;
3309
3310	if (!capable(CAP_DAC_READ_SEARCH))
3311		return -EPERM;
3312
3313	path = btrfs_alloc_path();
3314	if (!path) {
3315		ret = -ENOMEM;
3316		goto out;
3317	}
3318
3319	ipa = memdup_user(arg, sizeof(*ipa));
3320	if (IS_ERR(ipa)) {
3321		ret = PTR_ERR(ipa);
3322		ipa = NULL;
3323		goto out;
3324	}
3325
3326	size = min_t(u32, ipa->size, 4096);
3327	ipath = init_ipath(size, root, path);
3328	if (IS_ERR(ipath)) {
3329		ret = PTR_ERR(ipath);
3330		ipath = NULL;
3331		goto out;
3332	}
3333
3334	ret = paths_from_inode(ipa->inum, ipath);
3335	if (ret < 0)
3336		goto out;
3337
3338	for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3339		rel_ptr = ipath->fspath->val[i] -
3340			  (u64)(unsigned long)ipath->fspath->val;
3341		ipath->fspath->val[i] = rel_ptr;
3342	}
3343
3344	btrfs_free_path(path);
3345	path = NULL;
3346	ret = copy_to_user((void __user *)(unsigned long)ipa->fspath,
3347			   ipath->fspath, size);
3348	if (ret) {
3349		ret = -EFAULT;
3350		goto out;
3351	}
3352
3353out:
3354	btrfs_free_path(path);
3355	free_ipath(ipath);
3356	kfree(ipa);
3357
3358	return ret;
3359}
3360
3361static long btrfs_ioctl_logical_to_ino(struct btrfs_fs_info *fs_info,
3362					void __user *arg, int version)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3363{
3364	int ret = 0;
3365	int size;
 
3366	struct btrfs_ioctl_logical_ino_args *loi;
3367	struct btrfs_data_container *inodes = NULL;
3368	struct btrfs_path *path = NULL;
3369	bool ignore_offset;
3370
3371	if (!capable(CAP_SYS_ADMIN))
3372		return -EPERM;
3373
3374	loi = memdup_user(arg, sizeof(*loi));
3375	if (IS_ERR(loi))
3376		return PTR_ERR(loi);
 
 
 
3377
3378	if (version == 1) {
3379		ignore_offset = false;
3380		size = min_t(u32, loi->size, SZ_64K);
3381	} else {
3382		/* All reserved bits must be 0 for now */
3383		if (memchr_inv(loi->reserved, 0, sizeof(loi->reserved))) {
3384			ret = -EINVAL;
3385			goto out_loi;
3386		}
3387		/* Only accept flags we have defined so far */
3388		if (loi->flags & ~(BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET)) {
3389			ret = -EINVAL;
3390			goto out_loi;
3391		}
3392		ignore_offset = loi->flags & BTRFS_LOGICAL_INO_ARGS_IGNORE_OFFSET;
3393		size = min_t(u32, loi->size, SZ_16M);
3394	}
3395
 
3396	inodes = init_data_container(size);
3397	if (IS_ERR(inodes)) {
3398		ret = PTR_ERR(inodes);
3399		goto out_loi;
3400	}
3401
3402	path = btrfs_alloc_path();
3403	if (!path) {
3404		ret = -ENOMEM;
3405		goto out;
3406	}
3407	ret = iterate_inodes_from_logical(loi->logical, fs_info, path,
3408					  inodes, ignore_offset);
3409	btrfs_free_path(path);
3410	if (ret == -EINVAL)
 
3411		ret = -ENOENT;
3412	if (ret < 0)
3413		goto out;
3414
3415	ret = copy_to_user((void __user *)(unsigned long)loi->inodes, inodes,
3416			   size);
 
 
 
 
 
 
 
 
3417	if (ret)
3418		ret = -EFAULT;
3419
3420out:
3421	kvfree(inodes);
3422out_loi:
3423	kfree(loi);
3424
3425	return ret;
3426}
3427
3428void btrfs_update_ioctl_balance_args(struct btrfs_fs_info *fs_info,
3429			       struct btrfs_ioctl_balance_args *bargs)
3430{
3431	struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3432
3433	bargs->flags = bctl->flags;
3434
3435	if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags))
3436		bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3437	if (atomic_read(&fs_info->balance_pause_req))
3438		bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3439	if (atomic_read(&fs_info->balance_cancel_req))
3440		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3441
3442	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3443	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3444	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3445
3446	spin_lock(&fs_info->balance_lock);
3447	memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3448	spin_unlock(&fs_info->balance_lock);
3449}
3450
3451/*
3452 * Try to acquire fs_info::balance_mutex as well as set BTRFS_EXLCOP_BALANCE as
3453 * required.
3454 *
3455 * @fs_info:       the filesystem
3456 * @excl_acquired: ptr to boolean value which is set to false in case balance
3457 *                 is being resumed
3458 *
3459 * Return 0 on success in which case both fs_info::balance is acquired as well
3460 * as exclusive ops are blocked. In case of failure return an error code.
3461 */
3462static int btrfs_try_lock_balance(struct btrfs_fs_info *fs_info, bool *excl_acquired)
3463{
3464	int ret;
3465
3466	/*
3467	 * Exclusive operation is locked. Three possibilities:
3468	 *   (1) some other op is running
3469	 *   (2) balance is running
3470	 *   (3) balance is paused -- special case (think resume)
3471	 */
3472	while (1) {
3473		if (btrfs_exclop_start(fs_info, BTRFS_EXCLOP_BALANCE)) {
3474			*excl_acquired = true;
3475			mutex_lock(&fs_info->balance_mutex);
3476			return 0;
3477		}
3478
3479		mutex_lock(&fs_info->balance_mutex);
3480		if (fs_info->balance_ctl) {
3481			/* This is either (2) or (3) */
3482			if (test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3483				/* This is (2) */
3484				ret = -EINPROGRESS;
3485				goto out_failure;
3486
3487			} else {
3488				mutex_unlock(&fs_info->balance_mutex);
3489				/*
3490				 * Lock released to allow other waiters to
3491				 * continue, we'll reexamine the status again.
3492				 */
3493				mutex_lock(&fs_info->balance_mutex);
3494
3495				if (fs_info->balance_ctl &&
3496				    !test_bit(BTRFS_FS_BALANCE_RUNNING, &fs_info->flags)) {
3497					/* This is (3) */
3498					*excl_acquired = false;
3499					return 0;
3500				}
3501			}
3502		} else {
3503			/* This is (1) */
3504			ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
3505			goto out_failure;
3506		}
3507
3508		mutex_unlock(&fs_info->balance_mutex);
3509	}
3510
3511out_failure:
3512	mutex_unlock(&fs_info->balance_mutex);
3513	*excl_acquired = false;
3514	return ret;
3515}
3516
3517static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3518{
3519	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3520	struct btrfs_fs_info *fs_info = root->fs_info;
3521	struct btrfs_ioctl_balance_args *bargs;
3522	struct btrfs_balance_control *bctl;
3523	bool need_unlock = true;
3524	int ret;
3525
3526	if (!capable(CAP_SYS_ADMIN))
3527		return -EPERM;
3528
3529	ret = mnt_want_write_file(file);
3530	if (ret)
3531		return ret;
3532
3533	bargs = memdup_user(arg, sizeof(*bargs));
3534	if (IS_ERR(bargs)) {
3535		ret = PTR_ERR(bargs);
3536		bargs = NULL;
3537		goto out;
3538	}
3539
3540	ret = btrfs_try_lock_balance(fs_info, &need_unlock);
3541	if (ret)
3542		goto out;
3543
3544	lockdep_assert_held(&fs_info->balance_mutex);
 
3545
3546	if (bargs->flags & BTRFS_BALANCE_RESUME) {
3547		if (!fs_info->balance_ctl) {
3548			ret = -ENOTCONN;
3549			goto out_unlock;
 
3550		}
3551
3552		bctl = fs_info->balance_ctl;
3553		spin_lock(&fs_info->balance_lock);
3554		bctl->flags |= BTRFS_BALANCE_RESUME;
3555		spin_unlock(&fs_info->balance_lock);
3556		btrfs_exclop_balance(fs_info, BTRFS_EXCLOP_BALANCE);
3557
3558		goto do_balance;
3559	}
 
 
3560
3561	if (bargs->flags & ~(BTRFS_BALANCE_ARGS_MASK | BTRFS_BALANCE_TYPE_MASK)) {
3562		ret = -EINVAL;
3563		goto out_unlock;
 
3564	}
3565
3566	if (fs_info->balance_ctl) {
3567		ret = -EINPROGRESS;
3568		goto out_unlock;
3569	}
3570
3571	bctl = kzalloc(sizeof(*bctl), GFP_KERNEL);
3572	if (!bctl) {
3573		ret = -ENOMEM;
3574		goto out_unlock;
3575	}
3576
3577	memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3578	memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3579	memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
 
 
 
 
 
 
 
 
3580
3581	bctl->flags = bargs->flags;
3582do_balance:
 
3583	/*
3584	 * Ownership of bctl and exclusive operation goes to btrfs_balance.
3585	 * bctl is freed in reset_balance_state, or, if restriper was paused
3586	 * all the way until unmount, in free_fs_info.  The flag should be
3587	 * cleared after reset_balance_state.
3588	 */
3589	need_unlock = false;
3590
3591	ret = btrfs_balance(fs_info, bctl, bargs);
3592	bctl = NULL;
3593
3594	if (ret == 0 || ret == -ECANCELED) {
3595		if (copy_to_user(arg, bargs, sizeof(*bargs)))
3596			ret = -EFAULT;
3597	}
3598
3599	kfree(bctl);
3600out_unlock:
3601	mutex_unlock(&fs_info->balance_mutex);
3602	if (need_unlock)
3603		btrfs_exclop_finish(fs_info);
3604out:
3605	mnt_drop_write_file(file);
3606	kfree(bargs);
 
 
 
 
3607	return ret;
3608}
3609
3610static long btrfs_ioctl_balance_ctl(struct btrfs_fs_info *fs_info, int cmd)
3611{
3612	if (!capable(CAP_SYS_ADMIN))
3613		return -EPERM;
3614
3615	switch (cmd) {
3616	case BTRFS_BALANCE_CTL_PAUSE:
3617		return btrfs_pause_balance(fs_info);
3618	case BTRFS_BALANCE_CTL_CANCEL:
3619		return btrfs_cancel_balance(fs_info);
3620	}
3621
3622	return -EINVAL;
3623}
3624
3625static long btrfs_ioctl_balance_progress(struct btrfs_fs_info *fs_info,
3626					 void __user *arg)
3627{
 
3628	struct btrfs_ioctl_balance_args *bargs;
3629	int ret = 0;
3630
3631	if (!capable(CAP_SYS_ADMIN))
3632		return -EPERM;
3633
3634	mutex_lock(&fs_info->balance_mutex);
3635	if (!fs_info->balance_ctl) {
3636		ret = -ENOTCONN;
3637		goto out;
3638	}
3639
3640	bargs = kzalloc(sizeof(*bargs), GFP_KERNEL);
3641	if (!bargs) {
3642		ret = -ENOMEM;
3643		goto out;
3644	}
3645
3646	btrfs_update_ioctl_balance_args(fs_info, bargs);
3647
3648	if (copy_to_user(arg, bargs, sizeof(*bargs)))
3649		ret = -EFAULT;
3650
3651	kfree(bargs);
3652out:
3653	mutex_unlock(&fs_info->balance_mutex);
3654	return ret;
3655}
3656
3657static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
3658{
3659	struct inode *inode = file_inode(file);
3660	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3661	struct btrfs_ioctl_quota_ctl_args *sa;
3662	int ret;
3663
3664	if (!capable(CAP_SYS_ADMIN))
3665		return -EPERM;
3666
3667	ret = mnt_want_write_file(file);
3668	if (ret)
3669		return ret;
3670
3671	sa = memdup_user(arg, sizeof(*sa));
3672	if (IS_ERR(sa)) {
3673		ret = PTR_ERR(sa);
3674		goto drop_write;
3675	}
3676
3677	down_write(&fs_info->subvol_sem);
3678
3679	switch (sa->cmd) {
3680	case BTRFS_QUOTA_CTL_ENABLE:
3681		ret = btrfs_quota_enable(fs_info);
3682		break;
3683	case BTRFS_QUOTA_CTL_DISABLE:
3684		ret = btrfs_quota_disable(fs_info);
3685		break;
3686	default:
3687		ret = -EINVAL;
3688		break;
3689	}
3690
3691	kfree(sa);
3692	up_write(&fs_info->subvol_sem);
3693drop_write:
3694	mnt_drop_write_file(file);
3695	return ret;
3696}
3697
3698static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
3699{
3700	struct inode *inode = file_inode(file);
3701	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3702	struct btrfs_root *root = BTRFS_I(inode)->root;
3703	struct btrfs_ioctl_qgroup_assign_args *sa;
3704	struct btrfs_trans_handle *trans;
3705	int ret;
3706	int err;
3707
3708	if (!capable(CAP_SYS_ADMIN))
3709		return -EPERM;
3710
3711	ret = mnt_want_write_file(file);
3712	if (ret)
3713		return ret;
3714
3715	sa = memdup_user(arg, sizeof(*sa));
3716	if (IS_ERR(sa)) {
3717		ret = PTR_ERR(sa);
3718		goto drop_write;
3719	}
3720
3721	trans = btrfs_join_transaction(root);
3722	if (IS_ERR(trans)) {
3723		ret = PTR_ERR(trans);
3724		goto out;
3725	}
3726
3727	if (sa->assign) {
3728		ret = btrfs_add_qgroup_relation(trans, sa->src, sa->dst);
3729	} else {
3730		ret = btrfs_del_qgroup_relation(trans, sa->src, sa->dst);
3731	}
3732
3733	/* update qgroup status and info */
3734	err = btrfs_run_qgroups(trans);
3735	if (err < 0)
3736		btrfs_handle_fs_error(fs_info, err,
3737				      "failed to update qgroup status and info");
3738	err = btrfs_end_transaction(trans);
3739	if (err && !ret)
3740		ret = err;
3741
3742out:
3743	kfree(sa);
3744drop_write:
3745	mnt_drop_write_file(file);
3746	return ret;
3747}
3748
3749static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
3750{
3751	struct inode *inode = file_inode(file);
3752	struct btrfs_root *root = BTRFS_I(inode)->root;
3753	struct btrfs_ioctl_qgroup_create_args *sa;
3754	struct btrfs_trans_handle *trans;
3755	int ret;
3756	int err;
3757
3758	if (!capable(CAP_SYS_ADMIN))
3759		return -EPERM;
3760
3761	ret = mnt_want_write_file(file);
3762	if (ret)
3763		return ret;
3764
3765	sa = memdup_user(arg, sizeof(*sa));
3766	if (IS_ERR(sa)) {
3767		ret = PTR_ERR(sa);
3768		goto drop_write;
3769	}
3770
3771	if (!sa->qgroupid) {
3772		ret = -EINVAL;
3773		goto out;
3774	}
3775
3776	trans = btrfs_join_transaction(root);
3777	if (IS_ERR(trans)) {
3778		ret = PTR_ERR(trans);
3779		goto out;
3780	}
3781
3782	if (sa->create) {
3783		ret = btrfs_create_qgroup(trans, sa->qgroupid);
3784	} else {
3785		ret = btrfs_remove_qgroup(trans, sa->qgroupid);
3786	}
3787
3788	err = btrfs_end_transaction(trans);
3789	if (err && !ret)
3790		ret = err;
3791
3792out:
3793	kfree(sa);
3794drop_write:
3795	mnt_drop_write_file(file);
3796	return ret;
3797}
3798
3799static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
3800{
3801	struct inode *inode = file_inode(file);
3802	struct btrfs_root *root = BTRFS_I(inode)->root;
3803	struct btrfs_ioctl_qgroup_limit_args *sa;
3804	struct btrfs_trans_handle *trans;
3805	int ret;
3806	int err;
3807	u64 qgroupid;
3808
3809	if (!capable(CAP_SYS_ADMIN))
3810		return -EPERM;
3811
3812	ret = mnt_want_write_file(file);
3813	if (ret)
3814		return ret;
3815
3816	sa = memdup_user(arg, sizeof(*sa));
3817	if (IS_ERR(sa)) {
3818		ret = PTR_ERR(sa);
3819		goto drop_write;
3820	}
3821
3822	trans = btrfs_join_transaction(root);
3823	if (IS_ERR(trans)) {
3824		ret = PTR_ERR(trans);
3825		goto out;
3826	}
3827
3828	qgroupid = sa->qgroupid;
3829	if (!qgroupid) {
3830		/* take the current subvol as qgroup */
3831		qgroupid = root->root_key.objectid;
3832	}
3833
3834	ret = btrfs_limit_qgroup(trans, qgroupid, &sa->lim);
3835
3836	err = btrfs_end_transaction(trans);
3837	if (err && !ret)
3838		ret = err;
3839
3840out:
3841	kfree(sa);
3842drop_write:
3843	mnt_drop_write_file(file);
3844	return ret;
3845}
3846
3847static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
3848{
3849	struct inode *inode = file_inode(file);
3850	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3851	struct btrfs_ioctl_quota_rescan_args *qsa;
3852	int ret;
3853
3854	if (!capable(CAP_SYS_ADMIN))
3855		return -EPERM;
3856
3857	ret = mnt_want_write_file(file);
3858	if (ret)
3859		return ret;
3860
3861	qsa = memdup_user(arg, sizeof(*qsa));
3862	if (IS_ERR(qsa)) {
3863		ret = PTR_ERR(qsa);
3864		goto drop_write;
3865	}
3866
3867	if (qsa->flags) {
3868		ret = -EINVAL;
3869		goto out;
3870	}
3871
3872	ret = btrfs_qgroup_rescan(fs_info);
3873
3874out:
3875	kfree(qsa);
3876drop_write:
3877	mnt_drop_write_file(file);
3878	return ret;
3879}
3880
3881static long btrfs_ioctl_quota_rescan_status(struct btrfs_fs_info *fs_info,
3882						void __user *arg)
3883{
3884	struct btrfs_ioctl_quota_rescan_args qsa = {0};
3885
3886	if (!capable(CAP_SYS_ADMIN))
3887		return -EPERM;
3888
3889	if (fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
3890		qsa.flags = 1;
3891		qsa.progress = fs_info->qgroup_rescan_progress.objectid;
3892	}
3893
3894	if (copy_to_user(arg, &qsa, sizeof(qsa)))
3895		return -EFAULT;
3896
3897	return 0;
3898}
3899
3900static long btrfs_ioctl_quota_rescan_wait(struct btrfs_fs_info *fs_info,
3901						void __user *arg)
3902{
3903	if (!capable(CAP_SYS_ADMIN))
3904		return -EPERM;
3905
3906	return btrfs_qgroup_wait_for_completion(fs_info, true);
3907}
3908
3909static long _btrfs_ioctl_set_received_subvol(struct file *file,
3910					    struct user_namespace *mnt_userns,
3911					    struct btrfs_ioctl_received_subvol_args *sa)
3912{
3913	struct inode *inode = file_inode(file);
3914	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3915	struct btrfs_root *root = BTRFS_I(inode)->root;
3916	struct btrfs_root_item *root_item = &root->root_item;
3917	struct btrfs_trans_handle *trans;
3918	struct timespec64 ct = current_time(inode);
3919	int ret = 0;
3920	int received_uuid_changed;
3921
3922	if (!inode_owner_or_capable(mnt_userns, inode))
3923		return -EPERM;
3924
3925	ret = mnt_want_write_file(file);
3926	if (ret < 0)
3927		return ret;
3928
3929	down_write(&fs_info->subvol_sem);
3930
3931	if (btrfs_ino(BTRFS_I(inode)) != BTRFS_FIRST_FREE_OBJECTID) {
3932		ret = -EINVAL;
3933		goto out;
3934	}
3935
3936	if (btrfs_root_readonly(root)) {
3937		ret = -EROFS;
3938		goto out;
3939	}
3940
3941	/*
3942	 * 1 - root item
3943	 * 2 - uuid items (received uuid + subvol uuid)
3944	 */
3945	trans = btrfs_start_transaction(root, 3);
3946	if (IS_ERR(trans)) {
3947		ret = PTR_ERR(trans);
3948		trans = NULL;
3949		goto out;
3950	}
3951
3952	sa->rtransid = trans->transid;
3953	sa->rtime.sec = ct.tv_sec;
3954	sa->rtime.nsec = ct.tv_nsec;
3955
3956	received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
3957				       BTRFS_UUID_SIZE);
3958	if (received_uuid_changed &&
3959	    !btrfs_is_empty_uuid(root_item->received_uuid)) {
3960		ret = btrfs_uuid_tree_remove(trans, root_item->received_uuid,
3961					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3962					  root->root_key.objectid);
3963		if (ret && ret != -ENOENT) {
3964		        btrfs_abort_transaction(trans, ret);
3965		        btrfs_end_transaction(trans);
3966		        goto out;
3967		}
3968	}
3969	memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
3970	btrfs_set_root_stransid(root_item, sa->stransid);
3971	btrfs_set_root_rtransid(root_item, sa->rtransid);
3972	btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
3973	btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
3974	btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
3975	btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
3976
3977	ret = btrfs_update_root(trans, fs_info->tree_root,
3978				&root->root_key, &root->root_item);
3979	if (ret < 0) {
3980		btrfs_end_transaction(trans);
3981		goto out;
3982	}
3983	if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
3984		ret = btrfs_uuid_tree_add(trans, sa->uuid,
3985					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
3986					  root->root_key.objectid);
3987		if (ret < 0 && ret != -EEXIST) {
3988			btrfs_abort_transaction(trans, ret);
3989			btrfs_end_transaction(trans);
3990			goto out;
3991		}
3992	}
3993	ret = btrfs_commit_transaction(trans);
3994out:
3995	up_write(&fs_info->subvol_sem);
3996	mnt_drop_write_file(file);
3997	return ret;
3998}
3999
4000#ifdef CONFIG_64BIT
4001static long btrfs_ioctl_set_received_subvol_32(struct file *file,
4002						void __user *arg)
4003{
4004	struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
4005	struct btrfs_ioctl_received_subvol_args *args64 = NULL;
4006	int ret = 0;
4007
4008	args32 = memdup_user(arg, sizeof(*args32));
4009	if (IS_ERR(args32))
4010		return PTR_ERR(args32);
4011
4012	args64 = kmalloc(sizeof(*args64), GFP_KERNEL);
4013	if (!args64) {
4014		ret = -ENOMEM;
4015		goto out;
4016	}
4017
4018	memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
4019	args64->stransid = args32->stransid;
4020	args64->rtransid = args32->rtransid;
4021	args64->stime.sec = args32->stime.sec;
4022	args64->stime.nsec = args32->stime.nsec;
4023	args64->rtime.sec = args32->rtime.sec;
4024	args64->rtime.nsec = args32->rtime.nsec;
4025	args64->flags = args32->flags;
4026
4027	ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_user_ns(file), args64);
4028	if (ret)
4029		goto out;
4030
4031	memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
4032	args32->stransid = args64->stransid;
4033	args32->rtransid = args64->rtransid;
4034	args32->stime.sec = args64->stime.sec;
4035	args32->stime.nsec = args64->stime.nsec;
4036	args32->rtime.sec = args64->rtime.sec;
4037	args32->rtime.nsec = args64->rtime.nsec;
4038	args32->flags = args64->flags;
4039
4040	ret = copy_to_user(arg, args32, sizeof(*args32));
4041	if (ret)
4042		ret = -EFAULT;
4043
4044out:
4045	kfree(args32);
4046	kfree(args64);
4047	return ret;
4048}
4049#endif
4050
4051static long btrfs_ioctl_set_received_subvol(struct file *file,
4052					    void __user *arg)
4053{
4054	struct btrfs_ioctl_received_subvol_args *sa = NULL;
4055	int ret = 0;
4056
4057	sa = memdup_user(arg, sizeof(*sa));
4058	if (IS_ERR(sa))
4059		return PTR_ERR(sa);
4060
4061	ret = _btrfs_ioctl_set_received_subvol(file, file_mnt_user_ns(file), sa);
4062
4063	if (ret)
4064		goto out;
4065
4066	ret = copy_to_user(arg, sa, sizeof(*sa));
4067	if (ret)
4068		ret = -EFAULT;
4069
4070out:
4071	kfree(sa);
4072	return ret;
4073}
4074
4075static int btrfs_ioctl_get_fslabel(struct btrfs_fs_info *fs_info,
4076					void __user *arg)
4077{
4078	size_t len;
4079	int ret;
4080	char label[BTRFS_LABEL_SIZE];
4081
4082	spin_lock(&fs_info->super_lock);
4083	memcpy(label, fs_info->super_copy->label, BTRFS_LABEL_SIZE);
4084	spin_unlock(&fs_info->super_lock);
4085
4086	len = strnlen(label, BTRFS_LABEL_SIZE);
4087
4088	if (len == BTRFS_LABEL_SIZE) {
4089		btrfs_warn(fs_info,
4090			   "label is too long, return the first %zu bytes",
4091			   --len);
4092	}
4093
4094	ret = copy_to_user(arg, label, len);
4095
4096	return ret ? -EFAULT : 0;
4097}
4098
4099static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
4100{
4101	struct inode *inode = file_inode(file);
4102	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4103	struct btrfs_root *root = BTRFS_I(inode)->root;
4104	struct btrfs_super_block *super_block = fs_info->super_copy;
4105	struct btrfs_trans_handle *trans;
4106	char label[BTRFS_LABEL_SIZE];
4107	int ret;
4108
4109	if (!capable(CAP_SYS_ADMIN))
4110		return -EPERM;
4111
4112	if (copy_from_user(label, arg, sizeof(label)))
4113		return -EFAULT;
4114
4115	if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
4116		btrfs_err(fs_info,
4117			  "unable to set label with more than %d bytes",
4118			  BTRFS_LABEL_SIZE - 1);
4119		return -EINVAL;
4120	}
4121
4122	ret = mnt_want_write_file(file);
4123	if (ret)
4124		return ret;
4125
4126	trans = btrfs_start_transaction(root, 0);
4127	if (IS_ERR(trans)) {
4128		ret = PTR_ERR(trans);
4129		goto out_unlock;
4130	}
4131
4132	spin_lock(&fs_info->super_lock);
4133	strcpy(super_block->label, label);
4134	spin_unlock(&fs_info->super_lock);
4135	ret = btrfs_commit_transaction(trans);
4136
4137out_unlock:
4138	mnt_drop_write_file(file);
4139	return ret;
4140}
4141
4142#define INIT_FEATURE_FLAGS(suffix) \
4143	{ .compat_flags = BTRFS_FEATURE_COMPAT_##suffix, \
4144	  .compat_ro_flags = BTRFS_FEATURE_COMPAT_RO_##suffix, \
4145	  .incompat_flags = BTRFS_FEATURE_INCOMPAT_##suffix }
4146
4147int btrfs_ioctl_get_supported_features(void __user *arg)
4148{
4149	static const struct btrfs_ioctl_feature_flags features[3] = {
4150		INIT_FEATURE_FLAGS(SUPP),
4151		INIT_FEATURE_FLAGS(SAFE_SET),
4152		INIT_FEATURE_FLAGS(SAFE_CLEAR)
4153	};
4154
4155	if (copy_to_user(arg, &features, sizeof(features)))
4156		return -EFAULT;
4157
4158	return 0;
4159}
4160
4161static int btrfs_ioctl_get_features(struct btrfs_fs_info *fs_info,
4162					void __user *arg)
4163{
4164	struct btrfs_super_block *super_block = fs_info->super_copy;
4165	struct btrfs_ioctl_feature_flags features;
4166
4167	features.compat_flags = btrfs_super_compat_flags(super_block);
4168	features.compat_ro_flags = btrfs_super_compat_ro_flags(super_block);
4169	features.incompat_flags = btrfs_super_incompat_flags(super_block);
4170
4171	if (copy_to_user(arg, &features, sizeof(features)))
4172		return -EFAULT;
4173
4174	return 0;
4175}
4176
4177static int check_feature_bits(struct btrfs_fs_info *fs_info,
4178			      enum btrfs_feature_set set,
4179			      u64 change_mask, u64 flags, u64 supported_flags,
4180			      u64 safe_set, u64 safe_clear)
4181{
4182	const char *type = btrfs_feature_set_name(set);
4183	char *names;
4184	u64 disallowed, unsupported;
4185	u64 set_mask = flags & change_mask;
4186	u64 clear_mask = ~flags & change_mask;
4187
4188	unsupported = set_mask & ~supported_flags;
4189	if (unsupported) {
4190		names = btrfs_printable_features(set, unsupported);
4191		if (names) {
4192			btrfs_warn(fs_info,
4193				   "this kernel does not support the %s feature bit%s",
4194				   names, strchr(names, ',') ? "s" : "");
4195			kfree(names);
4196		} else
4197			btrfs_warn(fs_info,
4198				   "this kernel does not support %s bits 0x%llx",
4199				   type, unsupported);
4200		return -EOPNOTSUPP;
4201	}
4202
4203	disallowed = set_mask & ~safe_set;
4204	if (disallowed) {
4205		names = btrfs_printable_features(set, disallowed);
4206		if (names) {
4207			btrfs_warn(fs_info,
4208				   "can't set the %s feature bit%s while mounted",
4209				   names, strchr(names, ',') ? "s" : "");
4210			kfree(names);
4211		} else
4212			btrfs_warn(fs_info,
4213				   "can't set %s bits 0x%llx while mounted",
4214				   type, disallowed);
4215		return -EPERM;
4216	}
4217
4218	disallowed = clear_mask & ~safe_clear;
4219	if (disallowed) {
4220		names = btrfs_printable_features(set, disallowed);
4221		if (names) {
4222			btrfs_warn(fs_info,
4223				   "can't clear the %s feature bit%s while mounted",
4224				   names, strchr(names, ',') ? "s" : "");
4225			kfree(names);
4226		} else
4227			btrfs_warn(fs_info,
4228				   "can't clear %s bits 0x%llx while mounted",
4229				   type, disallowed);
4230		return -EPERM;
4231	}
4232
4233	return 0;
4234}
4235
4236#define check_feature(fs_info, change_mask, flags, mask_base)	\
4237check_feature_bits(fs_info, FEAT_##mask_base, change_mask, flags,	\
4238		   BTRFS_FEATURE_ ## mask_base ## _SUPP,	\
4239		   BTRFS_FEATURE_ ## mask_base ## _SAFE_SET,	\
4240		   BTRFS_FEATURE_ ## mask_base ## _SAFE_CLEAR)
4241
4242static int btrfs_ioctl_set_features(struct file *file, void __user *arg)
4243{
4244	struct inode *inode = file_inode(file);
4245	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4246	struct btrfs_root *root = BTRFS_I(inode)->root;
4247	struct btrfs_super_block *super_block = fs_info->super_copy;
4248	struct btrfs_ioctl_feature_flags flags[2];
4249	struct btrfs_trans_handle *trans;
4250	u64 newflags;
4251	int ret;
4252
4253	if (!capable(CAP_SYS_ADMIN))
4254		return -EPERM;
4255
4256	if (copy_from_user(flags, arg, sizeof(flags)))
4257		return -EFAULT;
4258
4259	/* Nothing to do */
4260	if (!flags[0].compat_flags && !flags[0].compat_ro_flags &&
4261	    !flags[0].incompat_flags)
4262		return 0;
4263
4264	ret = check_feature(fs_info, flags[0].compat_flags,
4265			    flags[1].compat_flags, COMPAT);
4266	if (ret)
4267		return ret;
4268
4269	ret = check_feature(fs_info, flags[0].compat_ro_flags,
4270			    flags[1].compat_ro_flags, COMPAT_RO);
4271	if (ret)
4272		return ret;
4273
4274	ret = check_feature(fs_info, flags[0].incompat_flags,
4275			    flags[1].incompat_flags, INCOMPAT);
4276	if (ret)
4277		return ret;
4278
4279	ret = mnt_want_write_file(file);
4280	if (ret)
4281		return ret;
4282
4283	trans = btrfs_start_transaction(root, 0);
4284	if (IS_ERR(trans)) {
4285		ret = PTR_ERR(trans);
4286		goto out_drop_write;
4287	}
4288
4289	spin_lock(&fs_info->super_lock);
4290	newflags = btrfs_super_compat_flags(super_block);
4291	newflags |= flags[0].compat_flags & flags[1].compat_flags;
4292	newflags &= ~(flags[0].compat_flags & ~flags[1].compat_flags);
4293	btrfs_set_super_compat_flags(super_block, newflags);
4294
4295	newflags = btrfs_super_compat_ro_flags(super_block);
4296	newflags |= flags[0].compat_ro_flags & flags[1].compat_ro_flags;
4297	newflags &= ~(flags[0].compat_ro_flags & ~flags[1].compat_ro_flags);
4298	btrfs_set_super_compat_ro_flags(super_block, newflags);
4299
4300	newflags = btrfs_super_incompat_flags(super_block);
4301	newflags |= flags[0].incompat_flags & flags[1].incompat_flags;
4302	newflags &= ~(flags[0].incompat_flags & ~flags[1].incompat_flags);
4303	btrfs_set_super_incompat_flags(super_block, newflags);
4304	spin_unlock(&fs_info->super_lock);
4305
4306	ret = btrfs_commit_transaction(trans);
4307out_drop_write:
4308	mnt_drop_write_file(file);
4309
4310	return ret;
4311}
4312
4313static int _btrfs_ioctl_send(struct inode *inode, void __user *argp, bool compat)
4314{
4315	struct btrfs_ioctl_send_args *arg;
4316	int ret;
4317
4318	if (compat) {
4319#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4320		struct btrfs_ioctl_send_args_32 args32;
4321
4322		ret = copy_from_user(&args32, argp, sizeof(args32));
4323		if (ret)
4324			return -EFAULT;
4325		arg = kzalloc(sizeof(*arg), GFP_KERNEL);
4326		if (!arg)
4327			return -ENOMEM;
4328		arg->send_fd = args32.send_fd;
4329		arg->clone_sources_count = args32.clone_sources_count;
4330		arg->clone_sources = compat_ptr(args32.clone_sources);
4331		arg->parent_root = args32.parent_root;
4332		arg->flags = args32.flags;
4333		memcpy(arg->reserved, args32.reserved,
4334		       sizeof(args32.reserved));
4335#else
4336		return -ENOTTY;
4337#endif
4338	} else {
4339		arg = memdup_user(argp, sizeof(*arg));
4340		if (IS_ERR(arg))
4341			return PTR_ERR(arg);
4342	}
4343	ret = btrfs_ioctl_send(inode, arg);
4344	kfree(arg);
4345	return ret;
4346}
4347
4348static int btrfs_ioctl_encoded_read(struct file *file, void __user *argp,
4349				    bool compat)
4350{
4351	struct btrfs_ioctl_encoded_io_args args = { 0 };
4352	size_t copy_end_kernel = offsetofend(struct btrfs_ioctl_encoded_io_args,
4353					     flags);
4354	size_t copy_end;
4355	struct iovec iovstack[UIO_FASTIOV];
4356	struct iovec *iov = iovstack;
4357	struct iov_iter iter;
4358	loff_t pos;
4359	struct kiocb kiocb;
4360	ssize_t ret;
4361
4362	if (!capable(CAP_SYS_ADMIN)) {
4363		ret = -EPERM;
4364		goto out_acct;
4365	}
4366
4367	if (compat) {
4368#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4369		struct btrfs_ioctl_encoded_io_args_32 args32;
4370
4371		copy_end = offsetofend(struct btrfs_ioctl_encoded_io_args_32,
4372				       flags);
4373		if (copy_from_user(&args32, argp, copy_end)) {
4374			ret = -EFAULT;
4375			goto out_acct;
4376		}
4377		args.iov = compat_ptr(args32.iov);
4378		args.iovcnt = args32.iovcnt;
4379		args.offset = args32.offset;
4380		args.flags = args32.flags;
4381#else
4382		return -ENOTTY;
4383#endif
4384	} else {
4385		copy_end = copy_end_kernel;
4386		if (copy_from_user(&args, argp, copy_end)) {
4387			ret = -EFAULT;
4388			goto out_acct;
4389		}
4390	}
4391	if (args.flags != 0) {
4392		ret = -EINVAL;
4393		goto out_acct;
4394	}
4395
4396	ret = import_iovec(ITER_DEST, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
4397			   &iov, &iter);
4398	if (ret < 0)
4399		goto out_acct;
4400
4401	if (iov_iter_count(&iter) == 0) {
4402		ret = 0;
4403		goto out_iov;
4404	}
4405	pos = args.offset;
4406	ret = rw_verify_area(READ, file, &pos, args.len);
4407	if (ret < 0)
4408		goto out_iov;
4409
4410	init_sync_kiocb(&kiocb, file);
4411	kiocb.ki_pos = pos;
4412
4413	ret = btrfs_encoded_read(&kiocb, &iter, &args);
4414	if (ret >= 0) {
4415		fsnotify_access(file);
4416		if (copy_to_user(argp + copy_end,
4417				 (char *)&args + copy_end_kernel,
4418				 sizeof(args) - copy_end_kernel))
4419			ret = -EFAULT;
4420	}
4421
4422out_iov:
4423	kfree(iov);
4424out_acct:
4425	if (ret > 0)
4426		add_rchar(current, ret);
4427	inc_syscr(current);
4428	return ret;
4429}
4430
4431static int btrfs_ioctl_encoded_write(struct file *file, void __user *argp, bool compat)
4432{
4433	struct btrfs_ioctl_encoded_io_args args;
4434	struct iovec iovstack[UIO_FASTIOV];
4435	struct iovec *iov = iovstack;
4436	struct iov_iter iter;
4437	loff_t pos;
4438	struct kiocb kiocb;
4439	ssize_t ret;
4440
4441	if (!capable(CAP_SYS_ADMIN)) {
4442		ret = -EPERM;
4443		goto out_acct;
4444	}
4445
4446	if (!(file->f_mode & FMODE_WRITE)) {
4447		ret = -EBADF;
4448		goto out_acct;
4449	}
4450
4451	if (compat) {
4452#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4453		struct btrfs_ioctl_encoded_io_args_32 args32;
4454
4455		if (copy_from_user(&args32, argp, sizeof(args32))) {
4456			ret = -EFAULT;
4457			goto out_acct;
4458		}
4459		args.iov = compat_ptr(args32.iov);
4460		args.iovcnt = args32.iovcnt;
4461		args.offset = args32.offset;
4462		args.flags = args32.flags;
4463		args.len = args32.len;
4464		args.unencoded_len = args32.unencoded_len;
4465		args.unencoded_offset = args32.unencoded_offset;
4466		args.compression = args32.compression;
4467		args.encryption = args32.encryption;
4468		memcpy(args.reserved, args32.reserved, sizeof(args.reserved));
4469#else
4470		return -ENOTTY;
4471#endif
4472	} else {
4473		if (copy_from_user(&args, argp, sizeof(args))) {
4474			ret = -EFAULT;
4475			goto out_acct;
4476		}
4477	}
4478
4479	ret = -EINVAL;
4480	if (args.flags != 0)
4481		goto out_acct;
4482	if (memchr_inv(args.reserved, 0, sizeof(args.reserved)))
4483		goto out_acct;
4484	if (args.compression == BTRFS_ENCODED_IO_COMPRESSION_NONE &&
4485	    args.encryption == BTRFS_ENCODED_IO_ENCRYPTION_NONE)
4486		goto out_acct;
4487	if (args.compression >= BTRFS_ENCODED_IO_COMPRESSION_TYPES ||
4488	    args.encryption >= BTRFS_ENCODED_IO_ENCRYPTION_TYPES)
4489		goto out_acct;
4490	if (args.unencoded_offset > args.unencoded_len)
4491		goto out_acct;
4492	if (args.len > args.unencoded_len - args.unencoded_offset)
4493		goto out_acct;
4494
4495	ret = import_iovec(ITER_SOURCE, args.iov, args.iovcnt, ARRAY_SIZE(iovstack),
4496			   &iov, &iter);
4497	if (ret < 0)
4498		goto out_acct;
4499
4500	file_start_write(file);
4501
4502	if (iov_iter_count(&iter) == 0) {
4503		ret = 0;
4504		goto out_end_write;
4505	}
4506	pos = args.offset;
4507	ret = rw_verify_area(WRITE, file, &pos, args.len);
4508	if (ret < 0)
4509		goto out_end_write;
4510
4511	init_sync_kiocb(&kiocb, file);
4512	ret = kiocb_set_rw_flags(&kiocb, 0);
4513	if (ret)
4514		goto out_end_write;
4515	kiocb.ki_pos = pos;
4516
4517	ret = btrfs_do_write_iter(&kiocb, &iter, &args);
4518	if (ret > 0)
4519		fsnotify_modify(file);
4520
4521out_end_write:
4522	file_end_write(file);
4523	kfree(iov);
4524out_acct:
4525	if (ret > 0)
4526		add_wchar(current, ret);
4527	inc_syscw(current);
4528	return ret;
4529}
4530
4531long btrfs_ioctl(struct file *file, unsigned int
4532		cmd, unsigned long arg)
4533{
4534	struct inode *inode = file_inode(file);
4535	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4536	struct btrfs_root *root = BTRFS_I(inode)->root;
4537	void __user *argp = (void __user *)arg;
4538
4539	switch (cmd) {
 
 
 
 
4540	case FS_IOC_GETVERSION:
4541		return btrfs_ioctl_getversion(inode, argp);
4542	case FS_IOC_GETFSLABEL:
4543		return btrfs_ioctl_get_fslabel(fs_info, argp);
4544	case FS_IOC_SETFSLABEL:
4545		return btrfs_ioctl_set_fslabel(file, argp);
4546	case FITRIM:
4547		return btrfs_ioctl_fitrim(fs_info, argp);
4548	case BTRFS_IOC_SNAP_CREATE:
4549		return btrfs_ioctl_snap_create(file, argp, 0);
4550	case BTRFS_IOC_SNAP_CREATE_V2:
4551		return btrfs_ioctl_snap_create_v2(file, argp, 0);
4552	case BTRFS_IOC_SUBVOL_CREATE:
4553		return btrfs_ioctl_snap_create(file, argp, 1);
4554	case BTRFS_IOC_SUBVOL_CREATE_V2:
4555		return btrfs_ioctl_snap_create_v2(file, argp, 1);
4556	case BTRFS_IOC_SNAP_DESTROY:
4557		return btrfs_ioctl_snap_destroy(file, argp, false);
4558	case BTRFS_IOC_SNAP_DESTROY_V2:
4559		return btrfs_ioctl_snap_destroy(file, argp, true);
4560	case BTRFS_IOC_SUBVOL_GETFLAGS:
4561		return btrfs_ioctl_subvol_getflags(inode, argp);
4562	case BTRFS_IOC_SUBVOL_SETFLAGS:
4563		return btrfs_ioctl_subvol_setflags(file, argp);
4564	case BTRFS_IOC_DEFAULT_SUBVOL:
4565		return btrfs_ioctl_default_subvol(file, argp);
4566	case BTRFS_IOC_DEFRAG:
4567		return btrfs_ioctl_defrag(file, NULL);
4568	case BTRFS_IOC_DEFRAG_RANGE:
4569		return btrfs_ioctl_defrag(file, argp);
4570	case BTRFS_IOC_RESIZE:
4571		return btrfs_ioctl_resize(file, argp);
4572	case BTRFS_IOC_ADD_DEV:
4573		return btrfs_ioctl_add_dev(fs_info, argp);
4574	case BTRFS_IOC_RM_DEV:
4575		return btrfs_ioctl_rm_dev(file, argp);
4576	case BTRFS_IOC_RM_DEV_V2:
4577		return btrfs_ioctl_rm_dev_v2(file, argp);
4578	case BTRFS_IOC_FS_INFO:
4579		return btrfs_ioctl_fs_info(fs_info, argp);
4580	case BTRFS_IOC_DEV_INFO:
4581		return btrfs_ioctl_dev_info(fs_info, argp);
 
 
 
 
 
 
 
 
 
 
4582	case BTRFS_IOC_TREE_SEARCH:
4583		return btrfs_ioctl_tree_search(inode, argp);
4584	case BTRFS_IOC_TREE_SEARCH_V2:
4585		return btrfs_ioctl_tree_search_v2(inode, argp);
4586	case BTRFS_IOC_INO_LOOKUP:
4587		return btrfs_ioctl_ino_lookup(root, argp);
4588	case BTRFS_IOC_INO_PATHS:
4589		return btrfs_ioctl_ino_to_path(root, argp);
4590	case BTRFS_IOC_LOGICAL_INO:
4591		return btrfs_ioctl_logical_to_ino(fs_info, argp, 1);
4592	case BTRFS_IOC_LOGICAL_INO_V2:
4593		return btrfs_ioctl_logical_to_ino(fs_info, argp, 2);
4594	case BTRFS_IOC_SPACE_INFO:
4595		return btrfs_ioctl_space_info(fs_info, argp);
4596	case BTRFS_IOC_SYNC: {
4597		int ret;
4598
4599		ret = btrfs_start_delalloc_roots(fs_info, LONG_MAX, false);
4600		if (ret)
4601			return ret;
4602		ret = btrfs_sync_fs(inode->i_sb, 1);
4603		/*
4604		 * The transaction thread may want to do more work,
4605		 * namely it pokes the cleaner kthread that will start
4606		 * processing uncleaned subvols.
4607		 */
4608		wake_up_process(fs_info->transaction_kthread);
4609		return ret;
4610	}
4611	case BTRFS_IOC_START_SYNC:
4612		return btrfs_ioctl_start_sync(root, argp);
4613	case BTRFS_IOC_WAIT_SYNC:
4614		return btrfs_ioctl_wait_sync(fs_info, argp);
4615	case BTRFS_IOC_SCRUB:
4616		return btrfs_ioctl_scrub(file, argp);
4617	case BTRFS_IOC_SCRUB_CANCEL:
4618		return btrfs_ioctl_scrub_cancel(fs_info);
4619	case BTRFS_IOC_SCRUB_PROGRESS:
4620		return btrfs_ioctl_scrub_progress(fs_info, argp);
4621	case BTRFS_IOC_BALANCE_V2:
4622		return btrfs_ioctl_balance(file, argp);
4623	case BTRFS_IOC_BALANCE_CTL:
4624		return btrfs_ioctl_balance_ctl(fs_info, arg);
4625	case BTRFS_IOC_BALANCE_PROGRESS:
4626		return btrfs_ioctl_balance_progress(fs_info, argp);
4627	case BTRFS_IOC_SET_RECEIVED_SUBVOL:
4628		return btrfs_ioctl_set_received_subvol(file, argp);
4629#ifdef CONFIG_64BIT
4630	case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
4631		return btrfs_ioctl_set_received_subvol_32(file, argp);
4632#endif
4633	case BTRFS_IOC_SEND:
4634		return _btrfs_ioctl_send(inode, argp, false);
4635#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4636	case BTRFS_IOC_SEND_32:
4637		return _btrfs_ioctl_send(inode, argp, true);
4638#endif
4639	case BTRFS_IOC_GET_DEV_STATS:
4640		return btrfs_ioctl_get_dev_stats(fs_info, argp);
4641	case BTRFS_IOC_QUOTA_CTL:
4642		return btrfs_ioctl_quota_ctl(file, argp);
4643	case BTRFS_IOC_QGROUP_ASSIGN:
4644		return btrfs_ioctl_qgroup_assign(file, argp);
4645	case BTRFS_IOC_QGROUP_CREATE:
4646		return btrfs_ioctl_qgroup_create(file, argp);
4647	case BTRFS_IOC_QGROUP_LIMIT:
4648		return btrfs_ioctl_qgroup_limit(file, argp);
4649	case BTRFS_IOC_QUOTA_RESCAN:
4650		return btrfs_ioctl_quota_rescan(file, argp);
4651	case BTRFS_IOC_QUOTA_RESCAN_STATUS:
4652		return btrfs_ioctl_quota_rescan_status(fs_info, argp);
4653	case BTRFS_IOC_QUOTA_RESCAN_WAIT:
4654		return btrfs_ioctl_quota_rescan_wait(fs_info, argp);
4655	case BTRFS_IOC_DEV_REPLACE:
4656		return btrfs_ioctl_dev_replace(fs_info, argp);
4657	case BTRFS_IOC_GET_SUPPORTED_FEATURES:
4658		return btrfs_ioctl_get_supported_features(argp);
4659	case BTRFS_IOC_GET_FEATURES:
4660		return btrfs_ioctl_get_features(fs_info, argp);
4661	case BTRFS_IOC_SET_FEATURES:
4662		return btrfs_ioctl_set_features(file, argp);
4663	case BTRFS_IOC_GET_SUBVOL_INFO:
4664		return btrfs_ioctl_get_subvol_info(inode, argp);
4665	case BTRFS_IOC_GET_SUBVOL_ROOTREF:
4666		return btrfs_ioctl_get_subvol_rootref(root, argp);
4667	case BTRFS_IOC_INO_LOOKUP_USER:
4668		return btrfs_ioctl_ino_lookup_user(file, argp);
4669	case FS_IOC_ENABLE_VERITY:
4670		return fsverity_ioctl_enable(file, (const void __user *)argp);
4671	case FS_IOC_MEASURE_VERITY:
4672		return fsverity_ioctl_measure(file, argp);
4673	case BTRFS_IOC_ENCODED_READ:
4674		return btrfs_ioctl_encoded_read(file, argp, false);
4675	case BTRFS_IOC_ENCODED_WRITE:
4676		return btrfs_ioctl_encoded_write(file, argp, false);
4677#if defined(CONFIG_64BIT) && defined(CONFIG_COMPAT)
4678	case BTRFS_IOC_ENCODED_READ_32:
4679		return btrfs_ioctl_encoded_read(file, argp, true);
4680	case BTRFS_IOC_ENCODED_WRITE_32:
4681		return btrfs_ioctl_encoded_write(file, argp, true);
4682#endif
4683	}
4684
4685	return -ENOTTY;
4686}
4687
4688#ifdef CONFIG_COMPAT
4689long btrfs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
4690{
4691	/*
4692	 * These all access 32-bit values anyway so no further
4693	 * handling is necessary.
4694	 */
4695	switch (cmd) {
4696	case FS_IOC32_GETVERSION:
4697		cmd = FS_IOC_GETVERSION;
4698		break;
4699	}
4700
4701	return btrfs_ioctl(file, cmd, (unsigned long) compat_ptr(arg));
4702}
4703#endif
v3.5.6
 
   1/*
   2 * Copyright (C) 2007 Oracle.  All rights reserved.
   3 *
   4 * This program is free software; you can redistribute it and/or
   5 * modify it under the terms of the GNU General Public
   6 * License v2 as published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11 * General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public
  14 * License along with this program; if not, write to the
  15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16 * Boston, MA 021110-1307, USA.
  17 */
  18
  19#include <linux/kernel.h>
  20#include <linux/bio.h>
  21#include <linux/buffer_head.h>
  22#include <linux/file.h>
  23#include <linux/fs.h>
  24#include <linux/fsnotify.h>
  25#include <linux/pagemap.h>
  26#include <linux/highmem.h>
  27#include <linux/time.h>
  28#include <linux/init.h>
  29#include <linux/string.h>
  30#include <linux/backing-dev.h>
  31#include <linux/mount.h>
  32#include <linux/mpage.h>
  33#include <linux/namei.h>
  34#include <linux/swap.h>
  35#include <linux/writeback.h>
  36#include <linux/statfs.h>
  37#include <linux/compat.h>
  38#include <linux/bit_spinlock.h>
  39#include <linux/security.h>
  40#include <linux/xattr.h>
  41#include <linux/vmalloc.h>
  42#include <linux/slab.h>
  43#include <linux/blkdev.h>
  44#include "compat.h"
 
 
 
 
 
 
  45#include "ctree.h"
  46#include "disk-io.h"
 
  47#include "transaction.h"
  48#include "btrfs_inode.h"
  49#include "ioctl.h"
  50#include "print-tree.h"
  51#include "volumes.h"
  52#include "locking.h"
  53#include "inode-map.h"
  54#include "backref.h"
  55#include "rcu-string.h"
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  56
  57/* Mask out flags that are inappropriate for the given type of inode. */
  58static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
 
  59{
  60	if (S_ISDIR(mode))
  61		return flags;
  62	else if (S_ISREG(mode))
  63		return flags & ~FS_DIRSYNC_FL;
  64	else
  65		return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
  66}
  67
  68/*
  69 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
 
  70 */
  71static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
  72{
  73	unsigned int iflags = 0;
 
 
  74
  75	if (flags & BTRFS_INODE_SYNC)
  76		iflags |= FS_SYNC_FL;
  77	if (flags & BTRFS_INODE_IMMUTABLE)
  78		iflags |= FS_IMMUTABLE_FL;
  79	if (flags & BTRFS_INODE_APPEND)
  80		iflags |= FS_APPEND_FL;
  81	if (flags & BTRFS_INODE_NODUMP)
  82		iflags |= FS_NODUMP_FL;
  83	if (flags & BTRFS_INODE_NOATIME)
  84		iflags |= FS_NOATIME_FL;
  85	if (flags & BTRFS_INODE_DIRSYNC)
  86		iflags |= FS_DIRSYNC_FL;
  87	if (flags & BTRFS_INODE_NODATACOW)
  88		iflags |= FS_NOCOW_FL;
 
 
  89
  90	if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
 
 
  91		iflags |= FS_COMPR_FL;
  92	else if (flags & BTRFS_INODE_NOCOMPRESS)
  93		iflags |= FS_NOCOMP_FL;
  94
  95	return iflags;
  96}
  97
  98/*
  99 * Update inode->i_flags based on the btrfs internal flags.
 100 */
 101void btrfs_update_iflags(struct inode *inode)
 102{
 103	struct btrfs_inode *ip = BTRFS_I(inode);
 
 104
 105	inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);
 106
 107	if (ip->flags & BTRFS_INODE_SYNC)
 108		inode->i_flags |= S_SYNC;
 109	if (ip->flags & BTRFS_INODE_IMMUTABLE)
 110		inode->i_flags |= S_IMMUTABLE;
 111	if (ip->flags & BTRFS_INODE_APPEND)
 112		inode->i_flags |= S_APPEND;
 113	if (ip->flags & BTRFS_INODE_NOATIME)
 114		inode->i_flags |= S_NOATIME;
 115	if (ip->flags & BTRFS_INODE_DIRSYNC)
 116		inode->i_flags |= S_DIRSYNC;
 
 
 
 
 117}
 118
 119/*
 120 * Inherit flags from the parent inode.
 121 *
 122 * Currently only the compression flags and the cow flags are inherited.
 123 */
 124void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
 125{
 126	unsigned int flags;
 
 
 
 
 
 127
 128	if (!dir)
 129		return;
 
 130
 131	flags = BTRFS_I(dir)->flags;
 
 132
 133	if (flags & BTRFS_INODE_NOCOMPRESS) {
 134		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
 135		BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
 136	} else if (flags & BTRFS_INODE_COMPRESS) {
 137		BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
 138		BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
 139	}
 140
 141	if (flags & BTRFS_INODE_NODATACOW)
 142		BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
 143
 144	btrfs_update_iflags(inode);
 145}
 146
 147static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
 
 148{
 149	struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
 150	unsigned int flags = btrfs_flags_to_ioctl(ip->flags);
 151
 152	if (copy_to_user(arg, &flags, sizeof(flags)))
 153		return -EFAULT;
 154	return 0;
 155}
 156
 157static int check_flags(unsigned int flags)
 
 
 
 
 158{
 159	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
 160		      FS_NOATIME_FL | FS_NODUMP_FL | \
 161		      FS_SYNC_FL | FS_DIRSYNC_FL | \
 162		      FS_NOCOMP_FL | FS_COMPR_FL |
 163		      FS_NOCOW_FL))
 164		return -EOPNOTSUPP;
 165
 166	if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
 167		return -EINVAL;
 168
 
 169	return 0;
 170}
 171
 172static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
 
 173{
 174	struct inode *inode = file->f_path.dentry->d_inode;
 175	struct btrfs_inode *ip = BTRFS_I(inode);
 176	struct btrfs_root *root = ip->root;
 
 177	struct btrfs_trans_handle *trans;
 178	unsigned int flags, oldflags;
 179	int ret;
 180	u64 ip_oldflags;
 181	unsigned int i_oldflags;
 182
 183	if (btrfs_root_readonly(root))
 184		return -EROFS;
 185
 186	if (copy_from_user(&flags, arg, sizeof(flags)))
 187		return -EFAULT;
 188
 189	ret = check_flags(flags);
 
 
 190	if (ret)
 191		return ret;
 192
 193	if (!inode_owner_or_capable(inode))
 194		return -EACCES;
 195
 196	mutex_lock(&inode->i_mutex);
 197
 198	ip_oldflags = ip->flags;
 199	i_oldflags = inode->i_flags;
 200
 201	flags = btrfs_mask_flags(inode->i_mode, flags);
 202	oldflags = btrfs_flags_to_ioctl(ip->flags);
 203	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
 204		if (!capable(CAP_LINUX_IMMUTABLE)) {
 205			ret = -EPERM;
 206			goto out_unlock;
 207		}
 208	}
 209
 210	ret = mnt_want_write_file(file);
 211	if (ret)
 212		goto out_unlock;
 213
 214	if (flags & FS_SYNC_FL)
 215		ip->flags |= BTRFS_INODE_SYNC;
 
 216	else
 217		ip->flags &= ~BTRFS_INODE_SYNC;
 218	if (flags & FS_IMMUTABLE_FL)
 219		ip->flags |= BTRFS_INODE_IMMUTABLE;
 220	else
 221		ip->flags &= ~BTRFS_INODE_IMMUTABLE;
 222	if (flags & FS_APPEND_FL)
 223		ip->flags |= BTRFS_INODE_APPEND;
 224	else
 225		ip->flags &= ~BTRFS_INODE_APPEND;
 226	if (flags & FS_NODUMP_FL)
 227		ip->flags |= BTRFS_INODE_NODUMP;
 228	else
 229		ip->flags &= ~BTRFS_INODE_NODUMP;
 230	if (flags & FS_NOATIME_FL)
 231		ip->flags |= BTRFS_INODE_NOATIME;
 232	else
 233		ip->flags &= ~BTRFS_INODE_NOATIME;
 234	if (flags & FS_DIRSYNC_FL)
 235		ip->flags |= BTRFS_INODE_DIRSYNC;
 
 
 
 
 
 
 
 
 
 
 236	else
 237		ip->flags &= ~BTRFS_INODE_DIRSYNC;
 238	if (flags & FS_NOCOW_FL)
 239		ip->flags |= BTRFS_INODE_NODATACOW;
 240	else
 241		ip->flags &= ~BTRFS_INODE_NODATACOW;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 242
 243	/*
 244	 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
 245	 * flag may be changed automatically if compression code won't make
 246	 * things smaller.
 247	 */
 248	if (flags & FS_NOCOMP_FL) {
 249		ip->flags &= ~BTRFS_INODE_COMPRESS;
 250		ip->flags |= BTRFS_INODE_NOCOMPRESS;
 251	} else if (flags & FS_COMPR_FL) {
 252		ip->flags |= BTRFS_INODE_COMPRESS;
 253		ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
 
 
 
 
 
 
 
 
 254	} else {
 255		ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
 256	}
 257
 258	trans = btrfs_start_transaction(root, 1);
 259	if (IS_ERR(trans)) {
 260		ret = PTR_ERR(trans);
 261		goto out_drop;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 262	}
 263
 264	btrfs_update_iflags(inode);
 
 
 265	inode_inc_iversion(inode);
 266	inode->i_ctime = CURRENT_TIME;
 267	ret = btrfs_update_inode(trans, root, inode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 268
 269	btrfs_end_transaction(trans, root);
 270 out_drop:
 271	if (ret) {
 272		ip->flags = ip_oldflags;
 273		inode->i_flags = i_oldflags;
 274	}
 
 275
 276	mnt_drop_write_file(file);
 277 out_unlock:
 278	mutex_unlock(&inode->i_mutex);
 279	return ret;
 280}
 281
 282static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
 
 
 
 
 
 
 
 
 
 
 
 
 283{
 284	struct inode *inode = file->f_path.dentry->d_inode;
 
 
 
 
 
 
 
 
 285
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 286	return put_user(inode->i_generation, arg);
 287}
 288
 289static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
 
 290{
 291	struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
 292	struct btrfs_device *device;
 293	struct request_queue *q;
 294	struct fstrim_range range;
 295	u64 minlen = ULLONG_MAX;
 296	u64 num_devices = 0;
 297	u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
 298	int ret;
 299
 300	if (!capable(CAP_SYS_ADMIN))
 301		return -EPERM;
 302
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 303	rcu_read_lock();
 304	list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
 305				dev_list) {
 306		if (!device->bdev)
 307			continue;
 308		q = bdev_get_queue(device->bdev);
 309		if (blk_queue_discard(q)) {
 310			num_devices++;
 311			minlen = min((u64)q->limits.discard_granularity,
 312				     minlen);
 313		}
 314	}
 315	rcu_read_unlock();
 316
 317	if (!num_devices)
 318		return -EOPNOTSUPP;
 319	if (copy_from_user(&range, arg, sizeof(range)))
 320		return -EFAULT;
 321	if (range.start > total_bytes)
 
 
 
 
 
 
 322		return -EINVAL;
 323
 324	range.len = min(range.len, total_bytes - range.start);
 325	range.minlen = max(range.minlen, minlen);
 326	ret = btrfs_trim_fs(fs_info->tree_root, &range);
 327	if (ret < 0)
 328		return ret;
 329
 330	if (copy_to_user(arg, &range, sizeof(range)))
 331		return -EFAULT;
 332
 333	return 0;
 334}
 335
 336static noinline int create_subvol(struct btrfs_root *root,
 337				  struct dentry *dentry,
 338				  char *name, int namelen,
 339				  u64 *async_transid)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 340{
 
 341	struct btrfs_trans_handle *trans;
 342	struct btrfs_key key;
 343	struct btrfs_root_item root_item;
 344	struct btrfs_inode_item *inode_item;
 345	struct extent_buffer *leaf;
 
 346	struct btrfs_root *new_root;
 347	struct dentry *parent = dentry->d_parent;
 348	struct inode *dir;
 
 
 
 
 
 
 349	int ret;
 350	int err;
 351	u64 objectid;
 352	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 353	u64 index = 0;
 354
 355	ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
 
 
 
 
 356	if (ret)
 357		return ret;
 358
 359	dir = parent->d_inode;
 360
 361	/*
 362	 * 1 - inode item
 363	 * 2 - refs
 364	 * 1 - root item
 365	 * 2 - dir items
 366	 */
 367	trans = btrfs_start_transaction(root, 6);
 368	if (IS_ERR(trans))
 369		return PTR_ERR(trans);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 370
 371	leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
 372				      0, objectid, NULL, 0, 0, 0);
 373	if (IS_ERR(leaf)) {
 374		ret = PTR_ERR(leaf);
 375		goto fail;
 376	}
 377
 378	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
 379	btrfs_set_header_bytenr(leaf, leaf->start);
 380	btrfs_set_header_generation(leaf, trans->transid);
 381	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
 382	btrfs_set_header_owner(leaf, objectid);
 383
 384	write_extent_buffer(leaf, root->fs_info->fsid,
 385			    (unsigned long)btrfs_header_fsid(leaf),
 386			    BTRFS_FSID_SIZE);
 387	write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
 388			    (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
 389			    BTRFS_UUID_SIZE);
 390	btrfs_mark_buffer_dirty(leaf);
 391
 392	inode_item = &root_item.inode;
 393	memset(inode_item, 0, sizeof(*inode_item));
 394	inode_item->generation = cpu_to_le64(1);
 395	inode_item->size = cpu_to_le64(3);
 396	inode_item->nlink = cpu_to_le32(1);
 397	inode_item->nbytes = cpu_to_le64(root->leafsize);
 398	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);
 399
 400	root_item.flags = 0;
 401	root_item.byte_limit = 0;
 402	inode_item->flags = cpu_to_le64(BTRFS_INODE_ROOT_ITEM_INIT);
 403
 404	btrfs_set_root_bytenr(&root_item, leaf->start);
 405	btrfs_set_root_generation(&root_item, trans->transid);
 406	btrfs_set_root_level(&root_item, 0);
 407	btrfs_set_root_refs(&root_item, 1);
 408	btrfs_set_root_used(&root_item, leaf->len);
 409	btrfs_set_root_last_snapshot(&root_item, 0);
 410
 411	memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
 412	root_item.drop_level = 0;
 
 
 
 
 
 
 413
 414	btrfs_tree_unlock(leaf);
 415	free_extent_buffer(leaf);
 416	leaf = NULL;
 417
 418	btrfs_set_root_dirid(&root_item, new_dirid);
 419
 420	key.objectid = objectid;
 421	key.offset = 0;
 422	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
 423	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
 424				&root_item);
 425	if (ret)
 426		goto fail;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 427
 428	key.offset = (u64)-1;
 429	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
 430	if (IS_ERR(new_root)) {
 431		btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
 432		ret = PTR_ERR(new_root);
 433		goto fail;
 
 434	}
 
 
 
 
 435
 436	btrfs_record_root_in_trans(trans, new_root);
 437
 438	ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
 439	if (ret) {
 440		/* We potentially lose an unused inode item here */
 441		btrfs_abort_transaction(trans, root, ret);
 442		goto fail;
 443	}
 444
 445	/*
 446	 * insert the directory item
 447	 */
 448	ret = btrfs_set_inode_index(dir, &index);
 449	if (ret) {
 450		btrfs_abort_transaction(trans, root, ret);
 451		goto fail;
 452	}
 453
 454	ret = btrfs_insert_dir_item(trans, root,
 455				    name, namelen, dir, &key,
 456				    BTRFS_FT_DIR, index);
 457	if (ret) {
 458		btrfs_abort_transaction(trans, root, ret);
 459		goto fail;
 460	}
 461
 462	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
 463	ret = btrfs_update_inode(trans, root, dir);
 464	BUG_ON(ret);
 465
 466	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
 467				 objectid, root->root_key.objectid,
 468				 btrfs_ino(dir), index, name, namelen);
 
 469
 470	BUG_ON(ret);
 471
 472	d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
 473fail:
 474	if (async_transid) {
 475		*async_transid = trans->transid;
 476		err = btrfs_commit_transaction_async(trans, root, 1);
 477	} else {
 478		err = btrfs_commit_transaction(trans, root);
 479	}
 480	if (err && !ret)
 481		ret = err;
 
 482	return ret;
 483}
 484
 485static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
 486			   char *name, int namelen, u64 *async_transid,
 487			   bool readonly)
 488{
 
 489	struct inode *inode;
 490	struct btrfs_pending_snapshot *pending_snapshot;
 
 491	struct btrfs_trans_handle *trans;
 492	int ret;
 493
 494	if (!root->ref_cows)
 
 
 
 
 
 
 
 495		return -EINVAL;
 496
 497	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
 
 
 
 
 
 
 498	if (!pending_snapshot)
 499		return -ENOMEM;
 500
 501	btrfs_init_block_rsv(&pending_snapshot->block_rsv);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 502	pending_snapshot->dentry = dentry;
 503	pending_snapshot->root = root;
 504	pending_snapshot->readonly = readonly;
 
 
 505
 506	trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
 507	if (IS_ERR(trans)) {
 508		ret = PTR_ERR(trans);
 509		goto fail;
 510	}
 511
 512	ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
 513	BUG_ON(ret);
 514
 515	spin_lock(&root->fs_info->trans_lock);
 516	list_add(&pending_snapshot->list,
 517		 &trans->transaction->pending_snapshots);
 518	spin_unlock(&root->fs_info->trans_lock);
 519	if (async_transid) {
 520		*async_transid = trans->transid;
 521		ret = btrfs_commit_transaction_async(trans,
 522				     root->fs_info->extent_root, 1);
 523	} else {
 524		ret = btrfs_commit_transaction(trans,
 525					       root->fs_info->extent_root);
 526	}
 527	BUG_ON(ret);
 528
 529	ret = pending_snapshot->error;
 530	if (ret)
 531		goto fail;
 532
 533	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
 534	if (ret)
 535		goto fail;
 536
 537	inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
 538	if (IS_ERR(inode)) {
 539		ret = PTR_ERR(inode);
 540		goto fail;
 541	}
 542	BUG_ON(!inode);
 543	d_instantiate(dentry, inode);
 544	ret = 0;
 
 545fail:
 
 
 
 
 
 
 
 
 
 
 546	kfree(pending_snapshot);
 
 547	return ret;
 548}
 549
 550/*  copy of check_sticky in fs/namei.c()
 551* It's inline, so penalty for filesystems that don't use sticky bit is
 552* minimal.
 553*/
 554static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
 555{
 556	uid_t fsuid = current_fsuid();
 557
 558	if (!(dir->i_mode & S_ISVTX))
 559		return 0;
 560	if (inode->i_uid == fsuid)
 561		return 0;
 562	if (dir->i_uid == fsuid)
 563		return 0;
 564	return !capable(CAP_FOWNER);
 565}
 566
 567/*  copy of may_delete in fs/namei.c()
 568 *	Check whether we can remove a link victim from directory dir, check
 569 *  whether the type of victim is right.
 570 *  1. We can't do it if dir is read-only (done in permission())
 571 *  2. We should have write and exec permissions on dir
 572 *  3. We can't remove anything from append-only dir
 573 *  4. We can't do anything with immutable dir (done in permission())
 574 *  5. If the sticky bit on dir is set we should either
 575 *	a. be owner of dir, or
 576 *	b. be owner of victim, or
 577 *	c. have CAP_FOWNER capability
 578 *  6. If the victim is append-only or immutable we can't do antyhing with
 579 *     links pointing to it.
 580 *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 581 *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 582 *  9. We can't remove a root or mountpoint.
 583 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 584 *     nfs_async_unlink().
 585 */
 586
 587static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
 
 588{
 589	int error;
 590
 591	if (!victim->d_inode)
 592		return -ENOENT;
 593
 594	BUG_ON(victim->d_parent->d_inode != dir);
 595	audit_inode_child(victim, dir);
 596
 597	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
 598	if (error)
 599		return error;
 600	if (IS_APPEND(dir))
 601		return -EPERM;
 602	if (btrfs_check_sticky(dir, victim->d_inode)||
 603		IS_APPEND(victim->d_inode)||
 604	    IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
 605		return -EPERM;
 606	if (isdir) {
 607		if (!S_ISDIR(victim->d_inode->i_mode))
 608			return -ENOTDIR;
 609		if (IS_ROOT(victim))
 610			return -EBUSY;
 611	} else if (S_ISDIR(victim->d_inode->i_mode))
 612		return -EISDIR;
 613	if (IS_DEADDIR(dir))
 614		return -ENOENT;
 615	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
 616		return -EBUSY;
 617	return 0;
 618}
 619
 620/* copy of may_create in fs/namei.c() */
 621static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
 
 622{
 623	if (child->d_inode)
 624		return -EEXIST;
 625	if (IS_DEADDIR(dir))
 626		return -ENOENT;
 627	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
 
 
 628}
 629
 630/*
 631 * Create a new subvolume below @parent.  This is largely modeled after
 632 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 633 * inside this filesystem so it's quite a bit simpler.
 634 */
 635static noinline int btrfs_mksubvol(struct path *parent,
 636				   char *name, int namelen,
 
 637				   struct btrfs_root *snap_src,
 638				   u64 *async_transid, bool readonly)
 
 639{
 640	struct inode *dir  = parent->dentry->d_inode;
 
 641	struct dentry *dentry;
 
 642	int error;
 643
 644	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
 
 
 645
 646	dentry = lookup_one_len(name, parent->dentry, namelen);
 647	error = PTR_ERR(dentry);
 648	if (IS_ERR(dentry))
 649		goto out_unlock;
 650
 651	error = -EEXIST;
 652	if (dentry->d_inode)
 653		goto out_dput;
 654
 655	error = mnt_want_write(parent->mnt);
 
 
 
 
 
 656	if (error)
 657		goto out_dput;
 658
 659	error = btrfs_may_create(dir, dentry);
 660	if (error)
 661		goto out_drop_write;
 662
 663	down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 664
 665	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
 666		goto out_up_read;
 667
 668	if (snap_src) {
 669		error = create_snapshot(snap_src, dentry,
 670					name, namelen, async_transid, readonly);
 671	} else {
 672		error = create_subvol(BTRFS_I(dir)->root, dentry,
 673				      name, namelen, async_transid);
 674	}
 675	if (!error)
 676		fsnotify_mkdir(dir, dentry);
 677out_up_read:
 678	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
 679out_drop_write:
 680	mnt_drop_write(parent->mnt);
 681out_dput:
 682	dput(dentry);
 683out_unlock:
 684	mutex_unlock(&dir->i_mutex);
 685	return error;
 686}
 687
 688/*
 689 * When we're defragging a range, we don't want to kick it off again
 690 * if it is really just waiting for delalloc to send it down.
 691 * If we find a nice big extent or delalloc range for the bytes in the
 692 * file you want to defrag, we return 0 to let you know to skip this
 693 * part of the file
 694 */
 695static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
 696{
 697	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 698	struct extent_map *em = NULL;
 699	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 700	u64 end;
 701
 702	read_lock(&em_tree->lock);
 703	em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
 704	read_unlock(&em_tree->lock);
 705
 706	if (em) {
 707		end = extent_map_end(em);
 708		free_extent_map(em);
 709		if (end - offset > thresh)
 710			return 0;
 711	}
 712	/* if we already have a nice delalloc here, just stop */
 713	thresh /= 2;
 714	end = count_range_bits(io_tree, &offset, offset + thresh,
 715			       thresh, EXTENT_DELALLOC, 1);
 716	if (end >= thresh)
 717		return 0;
 718	return 1;
 719}
 720
 721/*
 722 * helper function to walk through a file and find extents
 723 * newer than a specific transid, and smaller than thresh.
 724 *
 725 * This is used by the defragging code to find new and small
 726 * extents
 727 */
 728static int find_new_extents(struct btrfs_root *root,
 729			    struct inode *inode, u64 newer_than,
 730			    u64 *off, int thresh)
 731{
 732	struct btrfs_path *path;
 733	struct btrfs_key min_key;
 734	struct btrfs_key max_key;
 735	struct extent_buffer *leaf;
 736	struct btrfs_file_extent_item *extent;
 737	int type;
 738	int ret;
 739	u64 ino = btrfs_ino(inode);
 740
 741	path = btrfs_alloc_path();
 742	if (!path)
 743		return -ENOMEM;
 744
 745	min_key.objectid = ino;
 746	min_key.type = BTRFS_EXTENT_DATA_KEY;
 747	min_key.offset = *off;
 748
 749	max_key.objectid = ino;
 750	max_key.type = (u8)-1;
 751	max_key.offset = (u64)-1;
 752
 753	path->keep_locks = 1;
 754
 755	while(1) {
 756		ret = btrfs_search_forward(root, &min_key, &max_key,
 757					   path, 0, newer_than);
 758		if (ret != 0)
 759			goto none;
 760		if (min_key.objectid != ino)
 761			goto none;
 762		if (min_key.type != BTRFS_EXTENT_DATA_KEY)
 763			goto none;
 764
 765		leaf = path->nodes[0];
 766		extent = btrfs_item_ptr(leaf, path->slots[0],
 767					struct btrfs_file_extent_item);
 768
 769		type = btrfs_file_extent_type(leaf, extent);
 770		if (type == BTRFS_FILE_EXTENT_REG &&
 771		    btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
 772		    check_defrag_in_cache(inode, min_key.offset, thresh)) {
 773			*off = min_key.offset;
 774			btrfs_free_path(path);
 775			return 0;
 776		}
 777
 778		if (min_key.offset == (u64)-1)
 779			goto none;
 780
 781		min_key.offset++;
 782		btrfs_release_path(path);
 783	}
 784none:
 785	btrfs_free_path(path);
 786	return -ENOENT;
 787}
 788
 789static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
 790{
 791	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
 792	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 793	struct extent_map *em;
 794	u64 len = PAGE_CACHE_SIZE;
 795
 796	/*
 797	 * hopefully we have this extent in the tree already, try without
 798	 * the full extent lock
 
 799	 */
 800	read_lock(&em_tree->lock);
 801	em = lookup_extent_mapping(em_tree, start, len);
 802	read_unlock(&em_tree->lock);
 803
 804	if (!em) {
 805		/* get the big lock and read metadata off disk */
 806		lock_extent(io_tree, start, start + len - 1);
 807		em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
 808		unlock_extent(io_tree, start, start + len - 1);
 809
 810		if (IS_ERR(em))
 811			return NULL;
 812	}
 813
 814	return em;
 815}
 816
 817static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
 818{
 819	struct extent_map *next;
 820	bool ret = true;
 821
 822	/* this is the last extent */
 823	if (em->start + em->len >= i_size_read(inode))
 824		return false;
 825
 826	next = defrag_lookup_extent(inode, em->start + em->len);
 827	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
 828		ret = false;
 829
 830	free_extent_map(next);
 831	return ret;
 832}
 833
 834static int should_defrag_range(struct inode *inode, u64 start, int thresh,
 835			       u64 *last_len, u64 *skip, u64 *defrag_end)
 836{
 837	struct extent_map *em;
 838	int ret = 1;
 839	bool next_mergeable = true;
 840
 841	/*
 842	 * make sure that once we start defragging an extent, we keep on
 843	 * defragging it
 
 844	 */
 845	if (start < *defrag_end)
 846		return 1;
 847
 848	*skip = 0;
 849
 850	em = defrag_lookup_extent(inode, start);
 851	if (!em)
 852		return 0;
 853
 854	/* this will cover holes, and inline extents */
 855	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
 856		ret = 0;
 857		goto out;
 858	}
 859
 860	next_mergeable = defrag_check_next_extent(inode, em);
 861
 862	/*
 863	 * we hit a real extent, if it is big or the next extent is not a
 864	 * real extent, don't bother defragging it
 865	 */
 866	if ((*last_len == 0 || *last_len >= thresh) &&
 867	    (em->len >= thresh || !next_mergeable))
 868		ret = 0;
 869out:
 870	/*
 871	 * last_len ends up being a counter of how many bytes we've defragged.
 872	 * every time we choose not to defrag an extent, we reset *last_len
 873	 * so that the next tiny extent will force a defrag.
 874	 *
 875	 * The end result of this is that tiny extents before a single big
 876	 * extent will force at least part of that big extent to be defragged.
 877	 */
 878	if (ret) {
 879		*defrag_end = extent_map_end(em);
 880	} else {
 881		*last_len = 0;
 882		*skip = extent_map_end(em);
 883		*defrag_end = 0;
 884	}
 885
 886	free_extent_map(em);
 887	return ret;
 888}
 889
 890/*
 891 * it doesn't do much good to defrag one or two pages
 892 * at a time.  This pulls in a nice chunk of pages
 893 * to COW and defrag.
 894 *
 895 * It also makes sure the delalloc code has enough
 896 * dirty data to avoid making new small extents as part
 897 * of the defrag
 898 *
 899 * It's a good idea to start RA on this range
 900 * before calling this.
 901 */
 902static int cluster_pages_for_defrag(struct inode *inode,
 903				    struct page **pages,
 904				    unsigned long start_index,
 905				    int num_pages)
 906{
 907	unsigned long file_end;
 908	u64 isize = i_size_read(inode);
 909	u64 page_start;
 910	u64 page_end;
 911	u64 page_cnt;
 912	int ret;
 913	int i;
 914	int i_done;
 915	struct btrfs_ordered_extent *ordered;
 916	struct extent_state *cached_state = NULL;
 917	struct extent_io_tree *tree;
 918	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
 919
 920	file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
 921	if (!isize || start_index > file_end)
 922		return 0;
 923
 924	page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
 925
 926	ret = btrfs_delalloc_reserve_space(inode,
 927					   page_cnt << PAGE_CACHE_SHIFT);
 928	if (ret)
 929		return ret;
 930	i_done = 0;
 931	tree = &BTRFS_I(inode)->io_tree;
 932
 933	/* step one, lock all the pages */
 934	for (i = 0; i < page_cnt; i++) {
 935		struct page *page;
 936again:
 937		page = find_or_create_page(inode->i_mapping,
 938					   start_index + i, mask);
 939		if (!page)
 940			break;
 941
 942		page_start = page_offset(page);
 943		page_end = page_start + PAGE_CACHE_SIZE - 1;
 944		while (1) {
 945			lock_extent(tree, page_start, page_end);
 946			ordered = btrfs_lookup_ordered_extent(inode,
 947							      page_start);
 948			unlock_extent(tree, page_start, page_end);
 949			if (!ordered)
 950				break;
 951
 952			unlock_page(page);
 953			btrfs_start_ordered_extent(inode, ordered, 1);
 954			btrfs_put_ordered_extent(ordered);
 955			lock_page(page);
 956			/*
 957			 * we unlocked the page above, so we need check if
 958			 * it was released or not.
 959			 */
 960			if (page->mapping != inode->i_mapping) {
 961				unlock_page(page);
 962				page_cache_release(page);
 963				goto again;
 964			}
 965		}
 966
 967		if (!PageUptodate(page)) {
 968			btrfs_readpage(NULL, page);
 969			lock_page(page);
 970			if (!PageUptodate(page)) {
 971				unlock_page(page);
 972				page_cache_release(page);
 973				ret = -EIO;
 974				break;
 975			}
 976		}
 977
 978		if (page->mapping != inode->i_mapping) {
 979			unlock_page(page);
 980			page_cache_release(page);
 981			goto again;
 982		}
 983
 984		pages[i] = page;
 985		i_done++;
 986	}
 987	if (!i_done || ret)
 988		goto out;
 989
 990	if (!(inode->i_sb->s_flags & MS_ACTIVE))
 991		goto out;
 992
 993	/*
 994	 * so now we have a nice long stream of locked
 995	 * and up to date pages, lets wait on them
 996	 */
 997	for (i = 0; i < i_done; i++)
 998		wait_on_page_writeback(pages[i]);
 999
1000	page_start = page_offset(pages[0]);
1001	page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;
1002
1003	lock_extent_bits(&BTRFS_I(inode)->io_tree,
1004			 page_start, page_end - 1, 0, &cached_state);
1005	clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
1006			  page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1007			  EXTENT_DO_ACCOUNTING, 0, 0, &cached_state,
1008			  GFP_NOFS);
1009
1010	if (i_done != page_cnt) {
1011		spin_lock(&BTRFS_I(inode)->lock);
1012		BTRFS_I(inode)->outstanding_extents++;
1013		spin_unlock(&BTRFS_I(inode)->lock);
1014		btrfs_delalloc_release_space(inode,
1015				     (page_cnt - i_done) << PAGE_CACHE_SHIFT);
1016	}
1017
1018
1019	btrfs_set_extent_delalloc(inode, page_start, page_end - 1,
1020				  &cached_state);
1021
1022	unlock_extent_cached(&BTRFS_I(inode)->io_tree,
1023			     page_start, page_end - 1, &cached_state,
1024			     GFP_NOFS);
1025
1026	for (i = 0; i < i_done; i++) {
1027		clear_page_dirty_for_io(pages[i]);
1028		ClearPageChecked(pages[i]);
1029		set_page_extent_mapped(pages[i]);
1030		set_page_dirty(pages[i]);
1031		unlock_page(pages[i]);
1032		page_cache_release(pages[i]);
1033	}
1034	return i_done;
1035out:
1036	for (i = 0; i < i_done; i++) {
1037		unlock_page(pages[i]);
1038		page_cache_release(pages[i]);
1039	}
1040	btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
1041	return ret;
1042
1043}
1044
1045int btrfs_defrag_file(struct inode *inode, struct file *file,
1046		      struct btrfs_ioctl_defrag_range_args *range,
1047		      u64 newer_than, unsigned long max_to_defrag)
1048{
1049	struct btrfs_root *root = BTRFS_I(inode)->root;
1050	struct btrfs_super_block *disk_super;
1051	struct file_ra_state *ra = NULL;
1052	unsigned long last_index;
1053	u64 isize = i_size_read(inode);
1054	u64 features;
1055	u64 last_len = 0;
1056	u64 skip = 0;
1057	u64 defrag_end = 0;
1058	u64 newer_off = range->start;
1059	unsigned long i;
1060	unsigned long ra_index = 0;
1061	int ret;
1062	int defrag_count = 0;
1063	int compress_type = BTRFS_COMPRESS_ZLIB;
1064	int extent_thresh = range->extent_thresh;
1065	int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
1066	int cluster = max_cluster;
1067	u64 new_align = ~((u64)128 * 1024 - 1);
1068	struct page **pages = NULL;
1069
1070	if (extent_thresh == 0)
1071		extent_thresh = 256 * 1024;
1072
1073	if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
1074		if (range->compress_type > BTRFS_COMPRESS_TYPES)
1075			return -EINVAL;
1076		if (range->compress_type)
1077			compress_type = range->compress_type;
1078	}
1079
1080	if (isize == 0)
1081		return 0;
1082
1083	/*
1084	 * if we were not given a file, allocate a readahead
1085	 * context
1086	 */
1087	if (!file) {
1088		ra = kzalloc(sizeof(*ra), GFP_NOFS);
1089		if (!ra)
1090			return -ENOMEM;
1091		file_ra_state_init(ra, inode->i_mapping);
1092	} else {
1093		ra = &file->f_ra;
1094	}
1095
1096	pages = kmalloc(sizeof(struct page *) * max_cluster,
1097			GFP_NOFS);
1098	if (!pages) {
1099		ret = -ENOMEM;
1100		goto out_ra;
1101	}
1102
1103	/* find the last page to defrag */
1104	if (range->start + range->len > range->start) {
1105		last_index = min_t(u64, isize - 1,
1106			 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
1107	} else {
1108		last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
1109	}
1110
1111	if (newer_than) {
1112		ret = find_new_extents(root, inode, newer_than,
1113				       &newer_off, 64 * 1024);
1114		if (!ret) {
1115			range->start = newer_off;
1116			/*
1117			 * we always align our defrag to help keep
1118			 * the extents in the file evenly spaced
1119			 */
1120			i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1121		} else
1122			goto out_ra;
1123	} else {
1124		i = range->start >> PAGE_CACHE_SHIFT;
1125	}
1126	if (!max_to_defrag)
1127		max_to_defrag = last_index + 1;
1128
1129	/*
1130	 * make writeback starts from i, so the defrag range can be
1131	 * written sequentially.
1132	 */
1133	if (i < inode->i_mapping->writeback_index)
1134		inode->i_mapping->writeback_index = i;
1135
1136	while (i <= last_index && defrag_count < max_to_defrag &&
1137	       (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
1138		PAGE_CACHE_SHIFT)) {
1139		/*
1140		 * make sure we stop running if someone unmounts
1141		 * the FS
1142		 */
1143		if (!(inode->i_sb->s_flags & MS_ACTIVE))
1144			break;
1145
1146		if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
1147					 extent_thresh, &last_len, &skip,
1148					 &defrag_end)) {
1149			unsigned long next;
1150			/*
1151			 * the should_defrag function tells us how much to skip
1152			 * bump our counter by the suggested amount
1153			 */
1154			next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
1155			i = max(i + 1, next);
1156			continue;
1157		}
1158
1159		if (!newer_than) {
1160			cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
1161				   PAGE_CACHE_SHIFT) - i;
1162			cluster = min(cluster, max_cluster);
1163		} else {
1164			cluster = max_cluster;
1165		}
1166
1167		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
1168			BTRFS_I(inode)->force_compress = compress_type;
1169
1170		if (i + cluster > ra_index) {
1171			ra_index = max(i, ra_index);
1172			btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
1173				       cluster);
1174			ra_index += max_cluster;
1175		}
1176
1177		mutex_lock(&inode->i_mutex);
1178		ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1179		if (ret < 0) {
1180			mutex_unlock(&inode->i_mutex);
1181			goto out_ra;
1182		}
1183
1184		defrag_count += ret;
1185		balance_dirty_pages_ratelimited_nr(inode->i_mapping, ret);
1186		mutex_unlock(&inode->i_mutex);
1187
1188		if (newer_than) {
1189			if (newer_off == (u64)-1)
1190				break;
1191
1192			if (ret > 0)
1193				i += ret;
1194
1195			newer_off = max(newer_off + 1,
1196					(u64)i << PAGE_CACHE_SHIFT);
1197
1198			ret = find_new_extents(root, inode,
1199					       newer_than, &newer_off,
1200					       64 * 1024);
1201			if (!ret) {
1202				range->start = newer_off;
1203				i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
1204			} else {
1205				break;
1206			}
1207		} else {
1208			if (ret > 0) {
1209				i += ret;
1210				last_len += ret << PAGE_CACHE_SHIFT;
1211			} else {
1212				i++;
1213				last_len = 0;
1214			}
1215		}
1216	}
1217
1218	if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
1219		filemap_flush(inode->i_mapping);
1220
1221	if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
1222		/* the filemap_flush will queue IO into the worker threads, but
1223		 * we have to make sure the IO is actually started and that
1224		 * ordered extents get created before we return
1225		 */
1226		atomic_inc(&root->fs_info->async_submit_draining);
1227		while (atomic_read(&root->fs_info->nr_async_submits) ||
1228		      atomic_read(&root->fs_info->async_delalloc_pages)) {
1229			wait_event(root->fs_info->async_submit_wait,
1230			   (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
1231			    atomic_read(&root->fs_info->async_delalloc_pages) == 0));
1232		}
1233		atomic_dec(&root->fs_info->async_submit_draining);
1234
1235		mutex_lock(&inode->i_mutex);
1236		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
1237		mutex_unlock(&inode->i_mutex);
1238	}
1239
1240	disk_super = root->fs_info->super_copy;
1241	features = btrfs_super_incompat_flags(disk_super);
1242	if (range->compress_type == BTRFS_COMPRESS_LZO) {
1243		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
1244		btrfs_set_super_incompat_flags(disk_super, features);
1245	}
1246
1247	ret = defrag_count;
1248
1249out_ra:
1250	if (!file)
1251		kfree(ra);
1252	kfree(pages);
1253	return ret;
1254}
1255
1256static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
1257					void __user *arg)
1258{
 
 
 
1259	u64 new_size;
1260	u64 old_size;
1261	u64 devid = 1;
 
1262	struct btrfs_ioctl_vol_args *vol_args;
1263	struct btrfs_trans_handle *trans;
1264	struct btrfs_device *device = NULL;
1265	char *sizestr;
 
1266	char *devstr = NULL;
1267	int ret = 0;
1268	int mod = 0;
1269
1270	if (root->fs_info->sb->s_flags & MS_RDONLY)
1271		return -EROFS;
1272
1273	if (!capable(CAP_SYS_ADMIN))
1274		return -EPERM;
1275
1276	mutex_lock(&root->fs_info->volume_mutex);
1277	if (root->fs_info->balance_ctl) {
1278		printk(KERN_INFO "btrfs: balance in progress\n");
1279		ret = -EINVAL;
1280		goto out;
1281	}
1282
 
 
 
 
1283	vol_args = memdup_user(arg, sizeof(*vol_args));
1284	if (IS_ERR(vol_args)) {
1285		ret = PTR_ERR(vol_args);
1286		goto out;
1287	}
1288
1289	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
 
 
 
 
 
 
1290
1291	sizestr = vol_args->name;
1292	devstr = strchr(sizestr, ':');
1293	if (devstr) {
1294		char *end;
1295		sizestr = devstr + 1;
1296		*devstr = '\0';
1297		devstr = vol_args->name;
1298		devid = simple_strtoull(devstr, &end, 10);
1299		printk(KERN_INFO "btrfs: resizing devid %llu\n",
1300		       (unsigned long long)devid);
 
 
 
 
 
1301	}
1302	device = btrfs_find_device(root, devid, NULL, NULL);
 
 
1303	if (!device) {
1304		printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1305		       (unsigned long long)devid);
1306		ret = -EINVAL;
1307		goto out_free;
1308	}
1309	if (device->fs_devices && device->fs_devices->seeding) {
1310		printk(KERN_INFO "btrfs: resizer unable to apply on "
1311		       "seeding device %llu\n",
1312		       (unsigned long long)devid);
1313		ret = -EINVAL;
1314		goto out_free;
 
1315	}
1316
1317	if (!strcmp(sizestr, "max"))
1318		new_size = device->bdev->bd_inode->i_size;
1319	else {
1320		if (sizestr[0] == '-') {
1321			mod = -1;
1322			sizestr++;
1323		} else if (sizestr[0] == '+') {
1324			mod = 1;
1325			sizestr++;
1326		}
1327		new_size = memparse(sizestr, NULL);
1328		if (new_size == 0) {
1329			ret = -EINVAL;
1330			goto out_free;
1331		}
1332	}
1333
1334	old_size = device->total_bytes;
 
 
 
 
 
1335
1336	if (mod < 0) {
1337		if (new_size > old_size) {
1338			ret = -EINVAL;
1339			goto out_free;
1340		}
1341		new_size = old_size - new_size;
1342	} else if (mod > 0) {
 
 
 
 
1343		new_size = old_size + new_size;
1344	}
1345
1346	if (new_size < 256 * 1024 * 1024) {
1347		ret = -EINVAL;
1348		goto out_free;
1349	}
1350	if (new_size > device->bdev->bd_inode->i_size) {
1351		ret = -EFBIG;
1352		goto out_free;
1353	}
1354
1355	do_div(new_size, root->sectorsize);
1356	new_size *= root->sectorsize;
1357
1358	printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1359		      rcu_str_deref(device->name),
1360		      (unsigned long long)new_size);
1361
1362	if (new_size > old_size) {
1363		trans = btrfs_start_transaction(root, 0);
1364		if (IS_ERR(trans)) {
1365			ret = PTR_ERR(trans);
1366			goto out_free;
1367		}
1368		ret = btrfs_grow_device(trans, device, new_size);
1369		btrfs_commit_transaction(trans, root);
1370	} else if (new_size < old_size) {
1371		ret = btrfs_shrink_device(device, new_size);
1372	}
1373
 
 
 
 
 
 
 
1374out_free:
1375	kfree(vol_args);
1376out:
1377	mutex_unlock(&root->fs_info->volume_mutex);
1378	return ret;
1379}
1380
1381static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
1382						    char *name,
1383						    unsigned long fd,
1384						    int subvol,
1385						    u64 *transid,
1386						    bool readonly)
1387{
1388	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1389	struct file *src_file;
1390	int namelen;
1391	int ret = 0;
1392
1393	if (root->fs_info->sb->s_flags & MS_RDONLY)
1394		return -EROFS;
 
 
 
 
1395
1396	namelen = strlen(name);
1397	if (strchr(name, '/')) {
1398		ret = -EINVAL;
1399		goto out;
1400	}
1401
1402	if (name[0] == '.' &&
1403	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
1404		ret = -EEXIST;
1405		goto out;
1406	}
1407
1408	if (subvol) {
1409		ret = btrfs_mksubvol(&file->f_path, name, namelen,
1410				     NULL, transid, readonly);
1411	} else {
 
1412		struct inode *src_inode;
1413		src_file = fget(fd);
1414		if (!src_file) {
1415			ret = -EINVAL;
1416			goto out;
1417		}
1418
1419		src_inode = src_file->f_path.dentry->d_inode;
1420		if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
1421			printk(KERN_INFO "btrfs: Snapshot src from "
1422			       "another FS\n");
1423			ret = -EINVAL;
1424			fput(src_file);
1425			goto out;
 
 
 
 
 
 
 
 
 
1426		}
1427		ret = btrfs_mksubvol(&file->f_path, name, namelen,
1428				     BTRFS_I(src_inode)->root,
1429				     transid, readonly);
1430		fput(src_file);
1431	}
 
 
1432out:
1433	return ret;
1434}
1435
1436static noinline int btrfs_ioctl_snap_create(struct file *file,
1437					    void __user *arg, int subvol)
1438{
1439	struct btrfs_ioctl_vol_args *vol_args;
1440	int ret;
1441
 
 
 
1442	vol_args = memdup_user(arg, sizeof(*vol_args));
1443	if (IS_ERR(vol_args))
1444		return PTR_ERR(vol_args);
1445	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1446
1447	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1448					      vol_args->fd, subvol,
1449					      NULL, false);
1450
1451	kfree(vol_args);
1452	return ret;
1453}
1454
1455static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
1456					       void __user *arg, int subvol)
1457{
1458	struct btrfs_ioctl_vol_args_v2 *vol_args;
1459	int ret;
1460	u64 transid = 0;
1461	u64 *ptr = NULL;
1462	bool readonly = false;
 
 
 
 
1463
1464	vol_args = memdup_user(arg, sizeof(*vol_args));
1465	if (IS_ERR(vol_args))
1466		return PTR_ERR(vol_args);
1467	vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1468
1469	if (vol_args->flags &
1470	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
1471		ret = -EOPNOTSUPP;
1472		goto out;
1473	}
1474
1475	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
1476		ptr = &transid;
1477	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
1478		readonly = true;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1479
1480	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
1481					      vol_args->fd, subvol,
1482					      ptr, readonly);
1483
1484	if (ret == 0 && ptr &&
1485	    copy_to_user(arg +
1486			 offsetof(struct btrfs_ioctl_vol_args_v2,
1487				  transid), ptr, sizeof(*ptr)))
1488		ret = -EFAULT;
1489out:
 
 
 
 
 
 
1490	kfree(vol_args);
1491	return ret;
1492}
1493
1494static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
1495						void __user *arg)
1496{
1497	struct inode *inode = fdentry(file)->d_inode;
1498	struct btrfs_root *root = BTRFS_I(inode)->root;
1499	int ret = 0;
1500	u64 flags = 0;
1501
1502	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1503		return -EINVAL;
1504
1505	down_read(&root->fs_info->subvol_sem);
1506	if (btrfs_root_readonly(root))
1507		flags |= BTRFS_SUBVOL_RDONLY;
1508	up_read(&root->fs_info->subvol_sem);
1509
1510	if (copy_to_user(arg, &flags, sizeof(flags)))
1511		ret = -EFAULT;
1512
1513	return ret;
1514}
1515
1516static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
1517					      void __user *arg)
1518{
1519	struct inode *inode = fdentry(file)->d_inode;
 
1520	struct btrfs_root *root = BTRFS_I(inode)->root;
1521	struct btrfs_trans_handle *trans;
1522	u64 root_flags;
1523	u64 flags;
1524	int ret = 0;
1525
1526	if (root->fs_info->sb->s_flags & MS_RDONLY)
1527		return -EROFS;
1528
1529	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1530		return -EINVAL;
 
1531
1532	if (copy_from_user(&flags, arg, sizeof(flags)))
1533		return -EFAULT;
 
 
1534
1535	if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1536		return -EINVAL;
 
 
1537
1538	if (flags & ~BTRFS_SUBVOL_RDONLY)
1539		return -EOPNOTSUPP;
1540
1541	if (!inode_owner_or_capable(inode))
1542		return -EACCES;
1543
1544	down_write(&root->fs_info->subvol_sem);
1545
1546	/* nothing to do */
1547	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1548		goto out;
1549
1550	root_flags = btrfs_root_flags(&root->root_item);
1551	if (flags & BTRFS_SUBVOL_RDONLY)
1552		btrfs_set_root_flags(&root->root_item,
1553				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
1554	else
1555		btrfs_set_root_flags(&root->root_item,
 
 
 
 
 
 
1556				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);
 
 
 
 
 
 
 
 
 
 
1557
1558	trans = btrfs_start_transaction(root, 1);
1559	if (IS_ERR(trans)) {
1560		ret = PTR_ERR(trans);
1561		goto out_reset;
1562	}
1563
1564	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1565				&root->root_key, &root->root_item);
 
 
 
 
 
 
1566
1567	btrfs_commit_transaction(trans, root);
1568out_reset:
1569	if (ret)
1570		btrfs_set_root_flags(&root->root_item, root_flags);
 
 
 
 
1571out:
1572	up_write(&root->fs_info->subvol_sem);
1573	return ret;
1574}
1575
1576/*
1577 * helper to check if the subvolume references other subvolumes
1578 */
1579static noinline int may_destroy_subvol(struct btrfs_root *root)
1580{
1581	struct btrfs_path *path;
1582	struct btrfs_key key;
1583	int ret;
1584
1585	path = btrfs_alloc_path();
1586	if (!path)
1587		return -ENOMEM;
1588
1589	key.objectid = root->root_key.objectid;
1590	key.type = BTRFS_ROOT_REF_KEY;
1591	key.offset = (u64)-1;
1592
1593	ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
1594				&key, path, 0, 0);
1595	if (ret < 0)
1596		goto out;
1597	BUG_ON(ret == 0);
1598
1599	ret = 0;
1600	if (path->slots[0] > 0) {
1601		path->slots[0]--;
1602		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
1603		if (key.objectid == root->root_key.objectid &&
1604		    key.type == BTRFS_ROOT_REF_KEY)
1605			ret = -ENOTEMPTY;
1606	}
1607out:
1608	btrfs_free_path(path);
1609	return ret;
1610}
1611
1612static noinline int key_in_sk(struct btrfs_key *key,
1613			      struct btrfs_ioctl_search_key *sk)
1614{
1615	struct btrfs_key test;
1616	int ret;
1617
1618	test.objectid = sk->min_objectid;
1619	test.type = sk->min_type;
1620	test.offset = sk->min_offset;
1621
1622	ret = btrfs_comp_cpu_keys(key, &test);
1623	if (ret < 0)
1624		return 0;
1625
1626	test.objectid = sk->max_objectid;
1627	test.type = sk->max_type;
1628	test.offset = sk->max_offset;
1629
1630	ret = btrfs_comp_cpu_keys(key, &test);
1631	if (ret > 0)
1632		return 0;
1633	return 1;
1634}
1635
1636static noinline int copy_to_sk(struct btrfs_root *root,
1637			       struct btrfs_path *path,
1638			       struct btrfs_key *key,
1639			       struct btrfs_ioctl_search_key *sk,
1640			       char *buf,
 
1641			       unsigned long *sk_offset,
1642			       int *num_found)
1643{
1644	u64 found_transid;
1645	struct extent_buffer *leaf;
1646	struct btrfs_ioctl_search_header sh;
 
1647	unsigned long item_off;
1648	unsigned long item_len;
1649	int nritems;
1650	int i;
1651	int slot;
1652	int ret = 0;
1653
1654	leaf = path->nodes[0];
1655	slot = path->slots[0];
1656	nritems = btrfs_header_nritems(leaf);
1657
1658	if (btrfs_header_generation(leaf) > sk->max_transid) {
1659		i = nritems;
1660		goto advance_key;
1661	}
1662	found_transid = btrfs_header_generation(leaf);
1663
1664	for (i = slot; i < nritems; i++) {
1665		item_off = btrfs_item_ptr_offset(leaf, i);
1666		item_len = btrfs_item_size_nr(leaf, i);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1667
1668		if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1669			item_len = 0;
 
 
1670
1671		if (sizeof(sh) + item_len + *sk_offset >
1672		    BTRFS_SEARCH_ARGS_BUFSIZE) {
1673			ret = 1;
1674			goto overflow;
1675		}
1676
1677		btrfs_item_key_to_cpu(leaf, key, i);
1678		if (!key_in_sk(key, sk))
1679			continue;
1680
1681		sh.objectid = key->objectid;
1682		sh.offset = key->offset;
1683		sh.type = key->type;
1684		sh.len = item_len;
1685		sh.transid = found_transid;
1686
1687		/* copy search result header */
1688		memcpy(buf + *sk_offset, &sh, sizeof(sh));
 
 
 
 
 
 
 
 
 
1689		*sk_offset += sizeof(sh);
1690
1691		if (item_len) {
1692			char *p = buf + *sk_offset;
1693			/* copy the item */
1694			read_extent_buffer(leaf, p,
1695					   item_off, item_len);
 
 
 
 
 
 
 
 
1696			*sk_offset += item_len;
1697		}
1698		(*num_found)++;
1699
1700		if (*num_found >= sk->nr_items)
1701			break;
 
 
 
 
 
1702	}
1703advance_key:
1704	ret = 0;
1705	if (key->offset < (u64)-1 && key->offset < sk->max_offset)
 
 
 
 
 
1706		key->offset++;
1707	else if (key->type < (u8)-1 && key->type < sk->max_type) {
1708		key->offset = 0;
1709		key->type++;
1710	} else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
1711		key->offset = 0;
1712		key->type = 0;
1713		key->objectid++;
1714	} else
1715		ret = 1;
1716overflow:
 
 
 
 
 
 
 
 
 
1717	return ret;
1718}
1719
1720static noinline int search_ioctl(struct inode *inode,
1721				 struct btrfs_ioctl_search_args *args)
 
 
1722{
 
1723	struct btrfs_root *root;
1724	struct btrfs_key key;
1725	struct btrfs_key max_key;
1726	struct btrfs_path *path;
1727	struct btrfs_ioctl_search_key *sk = &args->key;
1728	struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
1729	int ret;
1730	int num_found = 0;
1731	unsigned long sk_offset = 0;
1732
 
 
 
 
 
1733	path = btrfs_alloc_path();
1734	if (!path)
1735		return -ENOMEM;
1736
1737	if (sk->tree_id == 0) {
1738		/* search the root of the inode that was passed */
1739		root = BTRFS_I(inode)->root;
1740	} else {
1741		key.objectid = sk->tree_id;
1742		key.type = BTRFS_ROOT_ITEM_KEY;
1743		key.offset = (u64)-1;
1744		root = btrfs_read_fs_root_no_name(info, &key);
1745		if (IS_ERR(root)) {
1746			printk(KERN_ERR "could not find root %llu\n",
1747			       sk->tree_id);
1748			btrfs_free_path(path);
1749			return -ENOENT;
1750		}
1751	}
1752
1753	key.objectid = sk->min_objectid;
1754	key.type = sk->min_type;
1755	key.offset = sk->min_offset;
1756
1757	max_key.objectid = sk->max_objectid;
1758	max_key.type = sk->max_type;
1759	max_key.offset = sk->max_offset;
1760
1761	path->keep_locks = 1;
1762
1763	while(1) {
1764		ret = btrfs_search_forward(root, &key, &max_key, path, 0,
1765					   sk->min_transid);
 
 
1766		if (ret != 0) {
1767			if (ret > 0)
1768				ret = 0;
1769			goto err;
1770		}
1771		ret = copy_to_sk(root, path, &key, sk, args->buf,
1772				 &sk_offset, &num_found);
1773		btrfs_release_path(path);
1774		if (ret || num_found >= sk->nr_items)
1775			break;
1776
1777	}
1778	ret = 0;
 
1779err:
1780	sk->nr_items = num_found;
 
1781	btrfs_free_path(path);
1782	return ret;
1783}
1784
1785static noinline int btrfs_ioctl_tree_search(struct file *file,
1786					   void __user *argp)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1787{
1788	 struct btrfs_ioctl_search_args *args;
1789	 struct inode *inode;
1790	 int ret;
 
 
1791
1792	if (!capable(CAP_SYS_ADMIN))
1793		return -EPERM;
1794
1795	args = memdup_user(argp, sizeof(*args));
1796	if (IS_ERR(args))
1797		return PTR_ERR(args);
 
 
1798
1799	inode = fdentry(file)->d_inode;
1800	ret = search_ioctl(inode, args);
1801	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
 
 
 
 
 
 
 
1802		ret = -EFAULT;
1803	kfree(args);
1804	return ret;
1805}
1806
1807/*
1808 * Search INODE_REFs to identify path name of 'dirid' directory
1809 * in a 'tree_id' tree. and sets path name to 'name'.
1810 */
1811static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
1812				u64 tree_id, u64 dirid, char *name)
1813{
1814	struct btrfs_root *root;
1815	struct btrfs_key key;
1816	char *ptr;
1817	int ret = -1;
1818	int slot;
1819	int len;
1820	int total_len = 0;
1821	struct btrfs_inode_ref *iref;
1822	struct extent_buffer *l;
1823	struct btrfs_path *path;
1824
1825	if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
1826		name[0]='\0';
1827		return 0;
1828	}
1829
1830	path = btrfs_alloc_path();
1831	if (!path)
1832		return -ENOMEM;
1833
1834	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1835
1836	key.objectid = tree_id;
1837	key.type = BTRFS_ROOT_ITEM_KEY;
1838	key.offset = (u64)-1;
1839	root = btrfs_read_fs_root_no_name(info, &key);
1840	if (IS_ERR(root)) {
1841		printk(KERN_ERR "could not find root %llu\n", tree_id);
1842		ret = -ENOENT;
1843		goto out;
1844	}
1845
1846	key.objectid = dirid;
1847	key.type = BTRFS_INODE_REF_KEY;
1848	key.offset = (u64)-1;
1849
1850	while(1) {
1851		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1852		if (ret < 0)
1853			goto out;
 
 
 
 
1854
1855		l = path->nodes[0];
1856		slot = path->slots[0];
1857		if (ret > 0 && slot > 0)
1858			slot--;
1859		btrfs_item_key_to_cpu(l, &key, slot);
1860
1861		if (ret > 0 && (key.objectid != dirid ||
1862				key.type != BTRFS_INODE_REF_KEY)) {
1863			ret = -ENOENT;
1864			goto out;
1865		}
1866
1867		iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
1868		len = btrfs_inode_ref_name_len(l, iref);
1869		ptr -= len + 1;
1870		total_len += len + 1;
1871		if (ptr < name)
 
1872			goto out;
 
1873
1874		*(ptr + len) = '/';
1875		read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);
1876
1877		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
1878			break;
1879
1880		btrfs_release_path(path);
1881		key.objectid = key.offset;
1882		key.offset = (u64)-1;
1883		dirid = key.objectid;
1884	}
1885	if (ptr < name)
1886		goto out;
1887	memmove(name, ptr, total_len);
1888	name[total_len]='\0';
1889	ret = 0;
1890out:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1891	btrfs_free_path(path);
1892	return ret;
1893}
1894
1895static noinline int btrfs_ioctl_ino_lookup(struct file *file,
1896					   void __user *argp)
1897{
1898	 struct btrfs_ioctl_ino_lookup_args *args;
1899	 struct inode *inode;
1900	 int ret;
1901
1902	if (!capable(CAP_SYS_ADMIN))
1903		return -EPERM;
1904
1905	args = memdup_user(argp, sizeof(*args));
1906	if (IS_ERR(args))
1907		return PTR_ERR(args);
1908
1909	inode = fdentry(file)->d_inode;
 
 
 
 
 
 
 
 
 
 
1910
1911	if (args->treeid == 0)
1912		args->treeid = BTRFS_I(inode)->root->root_key.objectid;
 
 
1913
1914	ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
1915					args->treeid, args->objectid,
1916					args->name);
1917
 
1918	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
1919		ret = -EFAULT;
1920
1921	kfree(args);
1922	return ret;
1923}
1924
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1925static noinline int btrfs_ioctl_snap_destroy(struct file *file,
1926					     void __user *arg)
 
1927{
1928	struct dentry *parent = fdentry(file);
 
1929	struct dentry *dentry;
1930	struct inode *dir = parent->d_inode;
1931	struct inode *inode;
1932	struct btrfs_root *root = BTRFS_I(dir)->root;
1933	struct btrfs_root *dest = NULL;
1934	struct btrfs_ioctl_vol_args *vol_args;
1935	struct btrfs_trans_handle *trans;
1936	int namelen;
1937	int ret;
 
1938	int err = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1939
1940	vol_args = memdup_user(arg, sizeof(*vol_args));
1941	if (IS_ERR(vol_args))
1942		return PTR_ERR(vol_args);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1943
1944	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
1945	namelen = strlen(vol_args->name);
1946	if (strchr(vol_args->name, '/') ||
1947	    strncmp(vol_args->name, "..", namelen) == 0) {
1948		err = -EINVAL;
1949		goto out;
1950	}
1951
1952	err = mnt_want_write_file(file);
1953	if (err)
1954		goto out;
 
1955
1956	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
1957	dentry = lookup_one_len(vol_args->name, parent, namelen);
 
 
1958	if (IS_ERR(dentry)) {
1959		err = PTR_ERR(dentry);
1960		goto out_unlock_dir;
1961	}
1962
1963	if (!dentry->d_inode) {
1964		err = -ENOENT;
1965		goto out_dput;
1966	}
1967
1968	inode = dentry->d_inode;
1969	dest = BTRFS_I(inode)->root;
1970	if (!capable(CAP_SYS_ADMIN)){
1971		/*
1972		 * Regular user.  Only allow this with a special mount
1973		 * option, when the user has write+exec access to the
1974		 * subvol root, and when rmdir(2) would have been
1975		 * allowed.
1976		 *
1977		 * Note that this is _not_ check that the subvol is
1978		 * empty or doesn't contain data that we wouldn't
1979		 * otherwise be able to delete.
1980		 *
1981		 * Users who want to delete empty subvols should try
1982		 * rmdir(2).
1983		 */
1984		err = -EPERM;
1985		if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
1986			goto out_dput;
1987
1988		/*
1989		 * Do not allow deletion if the parent dir is the same
1990		 * as the dir to be deleted.  That means the ioctl
1991		 * must be called on the dentry referencing the root
1992		 * of the subvol, not a random directory contained
1993		 * within it.
1994		 */
1995		err = -EINVAL;
1996		if (root == dest)
1997			goto out_dput;
1998
1999		err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
2000		if (err)
2001			goto out_dput;
 
2002
2003		/* check if subvolume may be deleted by a non-root user */
2004		err = btrfs_may_delete(dir, dentry, 1);
2005		if (err)
2006			goto out_dput;
2007	}
2008
2009	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2010		err = -EINVAL;
2011		goto out_dput;
2012	}
2013
2014	mutex_lock(&inode->i_mutex);
2015	err = d_invalidate(dentry);
2016	if (err)
2017		goto out_unlock;
2018
2019	down_write(&root->fs_info->subvol_sem);
2020
2021	err = may_destroy_subvol(dest);
2022	if (err)
2023		goto out_up_write;
2024
2025	trans = btrfs_start_transaction(root, 0);
2026	if (IS_ERR(trans)) {
2027		err = PTR_ERR(trans);
2028		goto out_up_write;
2029	}
2030	trans->block_rsv = &root->fs_info->global_block_rsv;
2031
2032	ret = btrfs_unlink_subvol(trans, root, dir,
2033				dest->root_key.objectid,
2034				dentry->d_name.name,
2035				dentry->d_name.len);
2036	if (ret) {
2037		err = ret;
2038		btrfs_abort_transaction(trans, root, ret);
2039		goto out_end_trans;
2040	}
2041
2042	btrfs_record_root_in_trans(trans, dest);
2043
2044	memset(&dest->root_item.drop_progress, 0,
2045		sizeof(dest->root_item.drop_progress));
2046	dest->root_item.drop_level = 0;
2047	btrfs_set_root_refs(&dest->root_item, 0);
2048
2049	if (!xchg(&dest->orphan_item_inserted, 1)) {
2050		ret = btrfs_insert_orphan_item(trans,
2051					root->fs_info->tree_root,
2052					dest->root_key.objectid);
2053		if (ret) {
2054			btrfs_abort_transaction(trans, root, ret);
2055			err = ret;
2056			goto out_end_trans;
2057		}
2058	}
2059out_end_trans:
2060	ret = btrfs_end_transaction(trans, root);
2061	if (ret && !err)
2062		err = ret;
2063	inode->i_flags |= S_DEAD;
2064out_up_write:
2065	up_write(&root->fs_info->subvol_sem);
2066out_unlock:
2067	mutex_unlock(&inode->i_mutex);
2068	if (!err) {
2069		shrink_dcache_sb(root->fs_info->sb);
2070		btrfs_invalidate_inodes(dest);
2071		d_delete(dentry);
2072	}
2073out_dput:
2074	dput(dentry);
2075out_unlock_dir:
2076	mutex_unlock(&dir->i_mutex);
 
 
 
 
 
 
2077	mnt_drop_write_file(file);
2078out:
 
2079	kfree(vol_args);
2080	return err;
2081}
2082
2083static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
2084{
2085	struct inode *inode = fdentry(file)->d_inode;
2086	struct btrfs_root *root = BTRFS_I(inode)->root;
2087	struct btrfs_ioctl_defrag_range_args *range;
2088	int ret;
2089
2090	if (btrfs_root_readonly(root))
2091		return -EROFS;
2092
2093	ret = mnt_want_write_file(file);
2094	if (ret)
2095		return ret;
2096
 
 
 
 
 
2097	switch (inode->i_mode & S_IFMT) {
2098	case S_IFDIR:
2099		if (!capable(CAP_SYS_ADMIN)) {
2100			ret = -EPERM;
2101			goto out;
2102		}
2103		ret = btrfs_defrag_root(root, 0);
2104		if (ret)
2105			goto out;
2106		ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
2107		break;
2108	case S_IFREG:
2109		if (!(file->f_mode & FMODE_WRITE)) {
2110			ret = -EINVAL;
2111			goto out;
2112		}
2113
2114		range = kzalloc(sizeof(*range), GFP_KERNEL);
2115		if (!range) {
2116			ret = -ENOMEM;
2117			goto out;
2118		}
2119
2120		if (argp) {
2121			if (copy_from_user(range, argp,
2122					   sizeof(*range))) {
2123				ret = -EFAULT;
2124				kfree(range);
2125				goto out;
2126			}
2127			/* compression requires us to start the IO */
2128			if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
2129				range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
2130				range->extent_thresh = (u32)-1;
2131			}
2132		} else {
2133			/* the rest are all set to zero by kzalloc */
2134			range->len = (u64)-1;
2135		}
2136		ret = btrfs_defrag_file(fdentry(file)->d_inode, file,
2137					range, 0, 0);
2138		if (ret > 0)
2139			ret = 0;
2140		kfree(range);
2141		break;
2142	default:
2143		ret = -EINVAL;
2144	}
2145out:
2146	mnt_drop_write_file(file);
2147	return ret;
2148}
2149
2150static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
2151{
2152	struct btrfs_ioctl_vol_args *vol_args;
 
2153	int ret;
2154
2155	if (!capable(CAP_SYS_ADMIN))
2156		return -EPERM;
2157
2158	mutex_lock(&root->fs_info->volume_mutex);
2159	if (root->fs_info->balance_ctl) {
2160		printk(KERN_INFO "btrfs: balance in progress\n");
2161		ret = -EINVAL;
2162		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
2163	}
2164
2165	vol_args = memdup_user(arg, sizeof(*vol_args));
2166	if (IS_ERR(vol_args)) {
2167		ret = PTR_ERR(vol_args);
2168		goto out;
2169	}
2170
2171	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2172	ret = btrfs_init_new_device(root, vol_args->name);
 
 
 
2173
2174	kfree(vol_args);
2175out:
2176	mutex_unlock(&root->fs_info->volume_mutex);
 
 
 
2177	return ret;
2178}
2179
2180static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
2181{
2182	struct btrfs_ioctl_vol_args *vol_args;
 
 
 
 
 
2183	int ret;
 
2184
2185	if (!capable(CAP_SYS_ADMIN))
2186		return -EPERM;
2187
2188	if (root->fs_info->sb->s_flags & MS_RDONLY)
2189		return -EROFS;
 
2190
2191	mutex_lock(&root->fs_info->volume_mutex);
2192	if (root->fs_info->balance_ctl) {
2193		printk(KERN_INFO "btrfs: balance in progress\n");
2194		ret = -EINVAL;
2195		goto out;
2196	}
2197
2198	vol_args = memdup_user(arg, sizeof(*vol_args));
2199	if (IS_ERR(vol_args)) {
2200		ret = PTR_ERR(vol_args);
 
 
 
 
 
 
 
 
 
 
2201		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2202	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2203
2204	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
2205	ret = btrfs_rm_device(root, vol_args->name);
 
 
 
 
 
 
2206
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2207	kfree(vol_args);
2208out:
2209	mutex_unlock(&root->fs_info->volume_mutex);
2210	return ret;
2211}
2212
2213static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
 
2214{
2215	struct btrfs_ioctl_fs_info_args *fi_args;
2216	struct btrfs_device *device;
2217	struct btrfs_device *next;
2218	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2219	int ret = 0;
2220
2221	if (!capable(CAP_SYS_ADMIN))
2222		return -EPERM;
 
2223
2224	fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
2225	if (!fi_args)
2226		return -ENOMEM;
2227
 
2228	fi_args->num_devices = fs_devices->num_devices;
2229	memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
2230
2231	mutex_lock(&fs_devices->device_list_mutex);
2232	list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2233		if (device->devid > fi_args->max_id)
2234			fi_args->max_id = device->devid;
2235	}
2236	mutex_unlock(&fs_devices->device_list_mutex);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2237
2238	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
2239		ret = -EFAULT;
2240
2241	kfree(fi_args);
2242	return ret;
2243}
2244
2245static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
 
2246{
 
2247	struct btrfs_ioctl_dev_info_args *di_args;
2248	struct btrfs_device *dev;
2249	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2250	int ret = 0;
2251	char *s_uuid = NULL;
2252	char empty_uuid[BTRFS_UUID_SIZE] = {0};
2253
2254	if (!capable(CAP_SYS_ADMIN))
2255		return -EPERM;
2256
2257	di_args = memdup_user(arg, sizeof(*di_args));
2258	if (IS_ERR(di_args))
2259		return PTR_ERR(di_args);
2260
2261	if (memcmp(empty_uuid, di_args->uuid, BTRFS_UUID_SIZE) != 0)
2262		s_uuid = di_args->uuid;
2263
2264	mutex_lock(&fs_devices->device_list_mutex);
2265	dev = btrfs_find_device(root, di_args->devid, s_uuid, NULL);
2266	mutex_unlock(&fs_devices->device_list_mutex);
2267
 
 
2268	if (!dev) {
2269		ret = -ENODEV;
2270		goto out;
2271	}
2272
2273	di_args->devid = dev->devid;
2274	di_args->bytes_used = dev->bytes_used;
2275	di_args->total_bytes = dev->total_bytes;
2276	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2277	if (dev->name) {
2278		struct rcu_string *name;
2279
2280		rcu_read_lock();
2281		name = rcu_dereference(dev->name);
2282		strncpy(di_args->path, name->str, sizeof(di_args->path));
2283		rcu_read_unlock();
2284		di_args->path[sizeof(di_args->path) - 1] = 0;
2285	} else {
2286		di_args->path[0] = '\0';
2287	}
2288
2289out:
 
2290	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
2291		ret = -EFAULT;
2292
2293	kfree(di_args);
2294	return ret;
2295}
2296
2297static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
2298				       u64 off, u64 olen, u64 destoff)
2299{
2300	struct inode *inode = fdentry(file)->d_inode;
2301	struct btrfs_root *root = BTRFS_I(inode)->root;
2302	struct file *src_file;
2303	struct inode *src;
2304	struct btrfs_trans_handle *trans;
2305	struct btrfs_path *path;
2306	struct extent_buffer *leaf;
2307	char *buf;
2308	struct btrfs_key key;
2309	u32 nritems;
2310	int slot;
2311	int ret;
2312	u64 len = olen;
2313	u64 bs = root->fs_info->sb->s_blocksize;
2314	u64 hint_byte;
2315
2316	/*
2317	 * TODO:
2318	 * - split compressed inline extents.  annoying: we need to
2319	 *   decompress into destination's address_space (the file offset
2320	 *   may change, so source mapping won't do), then recompress (or
2321	 *   otherwise reinsert) a subrange.
2322	 * - allow ranges within the same file to be cloned (provided
2323	 *   they don't overlap)?
2324	 */
2325
2326	/* the destination must be opened for writing */
2327	if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
2328		return -EINVAL;
2329
2330	if (btrfs_root_readonly(root))
2331		return -EROFS;
2332
2333	ret = mnt_want_write_file(file);
2334	if (ret)
2335		return ret;
2336
2337	src_file = fget(srcfd);
2338	if (!src_file) {
2339		ret = -EBADF;
2340		goto out_drop_write;
2341	}
2342
2343	src = src_file->f_dentry->d_inode;
2344
2345	ret = -EINVAL;
2346	if (src == inode)
2347		goto out_fput;
2348
2349	/* the src must be open for reading */
2350	if (!(src_file->f_mode & FMODE_READ))
2351		goto out_fput;
2352
2353	/* don't make the dst file partly checksummed */
2354	if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
2355	    (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
2356		goto out_fput;
2357
2358	ret = -EISDIR;
2359	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
2360		goto out_fput;
2361
2362	ret = -EXDEV;
2363	if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
2364		goto out_fput;
2365
2366	ret = -ENOMEM;
2367	buf = vmalloc(btrfs_level_size(root, 0));
2368	if (!buf)
2369		goto out_fput;
2370
2371	path = btrfs_alloc_path();
2372	if (!path) {
2373		vfree(buf);
2374		goto out_fput;
2375	}
2376	path->reada = 2;
2377
2378	if (inode < src) {
2379		mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
2380		mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
2381	} else {
2382		mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
2383		mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2384	}
2385
2386	/* determine range to clone */
2387	ret = -EINVAL;
2388	if (off + len > src->i_size || off + len < off)
2389		goto out_unlock;
2390	if (len == 0)
2391		olen = len = src->i_size - off;
2392	/* if we extend to eof, continue to block boundary */
2393	if (off + len == src->i_size)
2394		len = ALIGN(src->i_size, bs) - off;
2395
2396	/* verify the end result is block aligned */
2397	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
2398	    !IS_ALIGNED(destoff, bs))
2399		goto out_unlock;
2400
2401	if (destoff > inode->i_size) {
2402		ret = btrfs_cont_expand(inode, inode->i_size, destoff);
2403		if (ret)
2404			goto out_unlock;
2405	}
2406
2407	/* truncate page cache pages from target inode range */
2408	truncate_inode_pages_range(&inode->i_data, destoff,
2409				   PAGE_CACHE_ALIGN(destoff + len) - 1);
2410
2411	/* do any pending delalloc/csum calc on src, one way or
2412	   another, and lock file content */
2413	while (1) {
2414		struct btrfs_ordered_extent *ordered;
2415		lock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2416		ordered = btrfs_lookup_first_ordered_extent(src, off+len);
2417		if (!ordered &&
2418		    !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
2419				   EXTENT_DELALLOC, 0, NULL))
2420			break;
2421		unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2422		if (ordered)
2423			btrfs_put_ordered_extent(ordered);
2424		btrfs_wait_ordered_range(src, off, len);
2425	}
2426
2427	/* clone data */
2428	key.objectid = btrfs_ino(src);
2429	key.type = BTRFS_EXTENT_DATA_KEY;
2430	key.offset = 0;
2431
2432	while (1) {
2433		/*
2434		 * note the key will change type as we walk through the
2435		 * tree.
2436		 */
2437		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
2438		if (ret < 0)
2439			goto out;
2440
2441		nritems = btrfs_header_nritems(path->nodes[0]);
2442		if (path->slots[0] >= nritems) {
2443			ret = btrfs_next_leaf(root, path);
2444			if (ret < 0)
2445				goto out;
2446			if (ret > 0)
2447				break;
2448			nritems = btrfs_header_nritems(path->nodes[0]);
2449		}
2450		leaf = path->nodes[0];
2451		slot = path->slots[0];
2452
2453		btrfs_item_key_to_cpu(leaf, &key, slot);
2454		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
2455		    key.objectid != btrfs_ino(src))
2456			break;
2457
2458		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
2459			struct btrfs_file_extent_item *extent;
2460			int type;
2461			u32 size;
2462			struct btrfs_key new_key;
2463			u64 disko = 0, diskl = 0;
2464			u64 datao = 0, datal = 0;
2465			u8 comp;
2466			u64 endoff;
2467
2468			size = btrfs_item_size_nr(leaf, slot);
2469			read_extent_buffer(leaf, buf,
2470					   btrfs_item_ptr_offset(leaf, slot),
2471					   size);
2472
2473			extent = btrfs_item_ptr(leaf, slot,
2474						struct btrfs_file_extent_item);
2475			comp = btrfs_file_extent_compression(leaf, extent);
2476			type = btrfs_file_extent_type(leaf, extent);
2477			if (type == BTRFS_FILE_EXTENT_REG ||
2478			    type == BTRFS_FILE_EXTENT_PREALLOC) {
2479				disko = btrfs_file_extent_disk_bytenr(leaf,
2480								      extent);
2481				diskl = btrfs_file_extent_disk_num_bytes(leaf,
2482								 extent);
2483				datao = btrfs_file_extent_offset(leaf, extent);
2484				datal = btrfs_file_extent_num_bytes(leaf,
2485								    extent);
2486			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
2487				/* take upper bound, may be compressed */
2488				datal = btrfs_file_extent_ram_bytes(leaf,
2489								    extent);
2490			}
2491			btrfs_release_path(path);
2492
2493			if (key.offset + datal <= off ||
2494			    key.offset >= off+len)
2495				goto next;
2496
2497			memcpy(&new_key, &key, sizeof(new_key));
2498			new_key.objectid = btrfs_ino(inode);
2499			if (off <= key.offset)
2500				new_key.offset = key.offset + destoff - off;
2501			else
2502				new_key.offset = destoff;
2503
2504			/*
2505			 * 1 - adjusting old extent (we may have to split it)
2506			 * 1 - add new extent
2507			 * 1 - inode update
2508			 */
2509			trans = btrfs_start_transaction(root, 3);
2510			if (IS_ERR(trans)) {
2511				ret = PTR_ERR(trans);
2512				goto out;
2513			}
2514
2515			if (type == BTRFS_FILE_EXTENT_REG ||
2516			    type == BTRFS_FILE_EXTENT_PREALLOC) {
2517				/*
2518				 *    a  | --- range to clone ---|  b
2519				 * | ------------- extent ------------- |
2520				 */
2521
2522				/* substract range b */
2523				if (key.offset + datal > off + len)
2524					datal = off + len - key.offset;
2525
2526				/* substract range a */
2527				if (off > key.offset) {
2528					datao += off - key.offset;
2529					datal -= off - key.offset;
2530				}
2531
2532				ret = btrfs_drop_extents(trans, inode,
2533							 new_key.offset,
2534							 new_key.offset + datal,
2535							 &hint_byte, 1);
2536				if (ret) {
2537					btrfs_abort_transaction(trans, root,
2538								ret);
2539					btrfs_end_transaction(trans, root);
2540					goto out;
2541				}
2542
2543				ret = btrfs_insert_empty_item(trans, root, path,
2544							      &new_key, size);
2545				if (ret) {
2546					btrfs_abort_transaction(trans, root,
2547								ret);
2548					btrfs_end_transaction(trans, root);
2549					goto out;
2550				}
2551
2552				leaf = path->nodes[0];
2553				slot = path->slots[0];
2554				write_extent_buffer(leaf, buf,
2555					    btrfs_item_ptr_offset(leaf, slot),
2556					    size);
2557
2558				extent = btrfs_item_ptr(leaf, slot,
2559						struct btrfs_file_extent_item);
2560
2561				/* disko == 0 means it's a hole */
2562				if (!disko)
2563					datao = 0;
2564
2565				btrfs_set_file_extent_offset(leaf, extent,
2566							     datao);
2567				btrfs_set_file_extent_num_bytes(leaf, extent,
2568								datal);
2569				if (disko) {
2570					inode_add_bytes(inode, datal);
2571					ret = btrfs_inc_extent_ref(trans, root,
2572							disko, diskl, 0,
2573							root->root_key.objectid,
2574							btrfs_ino(inode),
2575							new_key.offset - datao,
2576							0);
2577					if (ret) {
2578						btrfs_abort_transaction(trans,
2579									root,
2580									ret);
2581						btrfs_end_transaction(trans,
2582								      root);
2583						goto out;
2584
2585					}
2586				}
2587			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
2588				u64 skip = 0;
2589				u64 trim = 0;
2590				if (off > key.offset) {
2591					skip = off - key.offset;
2592					new_key.offset += skip;
2593				}
2594
2595				if (key.offset + datal > off+len)
2596					trim = key.offset + datal - (off+len);
2597
2598				if (comp && (skip || trim)) {
2599					ret = -EINVAL;
2600					btrfs_end_transaction(trans, root);
2601					goto out;
2602				}
2603				size -= skip + trim;
2604				datal -= skip + trim;
2605
2606				ret = btrfs_drop_extents(trans, inode,
2607							 new_key.offset,
2608							 new_key.offset + datal,
2609							 &hint_byte, 1);
2610				if (ret) {
2611					btrfs_abort_transaction(trans, root,
2612								ret);
2613					btrfs_end_transaction(trans, root);
2614					goto out;
2615				}
2616
2617				ret = btrfs_insert_empty_item(trans, root, path,
2618							      &new_key, size);
2619				if (ret) {
2620					btrfs_abort_transaction(trans, root,
2621								ret);
2622					btrfs_end_transaction(trans, root);
2623					goto out;
2624				}
2625
2626				if (skip) {
2627					u32 start =
2628					  btrfs_file_extent_calc_inline_size(0);
2629					memmove(buf+start, buf+start+skip,
2630						datal);
2631				}
2632
2633				leaf = path->nodes[0];
2634				slot = path->slots[0];
2635				write_extent_buffer(leaf, buf,
2636					    btrfs_item_ptr_offset(leaf, slot),
2637					    size);
2638				inode_add_bytes(inode, datal);
2639			}
2640
2641			btrfs_mark_buffer_dirty(leaf);
2642			btrfs_release_path(path);
2643
2644			inode_inc_iversion(inode);
2645			inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2646
2647			/*
2648			 * we round up to the block size at eof when
2649			 * determining which extents to clone above,
2650			 * but shouldn't round up the file size
2651			 */
2652			endoff = new_key.offset + datal;
2653			if (endoff > destoff+olen)
2654				endoff = destoff+olen;
2655			if (endoff > inode->i_size)
2656				btrfs_i_size_write(inode, endoff);
2657
2658			ret = btrfs_update_inode(trans, root, inode);
2659			if (ret) {
2660				btrfs_abort_transaction(trans, root, ret);
2661				btrfs_end_transaction(trans, root);
2662				goto out;
2663			}
2664			ret = btrfs_end_transaction(trans, root);
2665		}
2666next:
2667		btrfs_release_path(path);
2668		key.offset++;
2669	}
2670	ret = 0;
2671out:
2672	btrfs_release_path(path);
2673	unlock_extent(&BTRFS_I(src)->io_tree, off, off+len);
2674out_unlock:
2675	mutex_unlock(&src->i_mutex);
2676	mutex_unlock(&inode->i_mutex);
2677	vfree(buf);
2678	btrfs_free_path(path);
2679out_fput:
2680	fput(src_file);
2681out_drop_write:
2682	mnt_drop_write_file(file);
2683	return ret;
2684}
2685
2686static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2687{
2688	struct btrfs_ioctl_clone_range_args args;
2689
2690	if (copy_from_user(&args, argp, sizeof(args)))
2691		return -EFAULT;
2692	return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
2693				 args.src_length, args.dest_offset);
2694}
2695
2696/*
2697 * there are many ways the trans_start and trans_end ioctls can lead
2698 * to deadlocks.  They should only be used by applications that
2699 * basically own the machine, and have a very in depth understanding
2700 * of all the possible deadlocks and enospc problems.
2701 */
2702static long btrfs_ioctl_trans_start(struct file *file)
2703{
2704	struct inode *inode = fdentry(file)->d_inode;
2705	struct btrfs_root *root = BTRFS_I(inode)->root;
2706	struct btrfs_trans_handle *trans;
2707	int ret;
2708
2709	ret = -EPERM;
2710	if (!capable(CAP_SYS_ADMIN))
2711		goto out;
2712
2713	ret = -EINPROGRESS;
2714	if (file->private_data)
2715		goto out;
2716
2717	ret = -EROFS;
2718	if (btrfs_root_readonly(root))
2719		goto out;
2720
2721	ret = mnt_want_write_file(file);
2722	if (ret)
2723		goto out;
2724
2725	atomic_inc(&root->fs_info->open_ioctl_trans);
2726
2727	ret = -ENOMEM;
2728	trans = btrfs_start_ioctl_transaction(root);
2729	if (IS_ERR(trans))
2730		goto out_drop;
2731
2732	file->private_data = trans;
2733	return 0;
2734
2735out_drop:
2736	atomic_dec(&root->fs_info->open_ioctl_trans);
2737	mnt_drop_write_file(file);
2738out:
2739	return ret;
2740}
2741
2742static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
2743{
2744	struct inode *inode = fdentry(file)->d_inode;
 
2745	struct btrfs_root *root = BTRFS_I(inode)->root;
2746	struct btrfs_root *new_root;
2747	struct btrfs_dir_item *di;
2748	struct btrfs_trans_handle *trans;
2749	struct btrfs_path *path;
2750	struct btrfs_key location;
2751	struct btrfs_disk_key disk_key;
2752	struct btrfs_super_block *disk_super;
2753	u64 features;
2754	u64 objectid = 0;
2755	u64 dir_id;
 
2756
2757	if (!capable(CAP_SYS_ADMIN))
2758		return -EPERM;
2759
2760	if (copy_from_user(&objectid, argp, sizeof(objectid)))
2761		return -EFAULT;
 
 
 
 
 
 
2762
2763	if (!objectid)
2764		objectid = root->root_key.objectid;
2765
2766	location.objectid = objectid;
2767	location.type = BTRFS_ROOT_ITEM_KEY;
2768	location.offset = (u64)-1;
2769
2770	new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
2771	if (IS_ERR(new_root))
2772		return PTR_ERR(new_root);
2773
2774	if (btrfs_root_refs(&new_root->root_item) == 0)
2775		return -ENOENT;
2776
2777	path = btrfs_alloc_path();
2778	if (!path)
2779		return -ENOMEM;
2780	path->leave_spinning = 1;
 
2781
2782	trans = btrfs_start_transaction(root, 1);
2783	if (IS_ERR(trans)) {
2784		btrfs_free_path(path);
2785		return PTR_ERR(trans);
2786	}
2787
2788	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
2789	di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
2790				   dir_id, "default", 7, 1);
2791	if (IS_ERR_OR_NULL(di)) {
2792		btrfs_free_path(path);
2793		btrfs_end_transaction(trans, root);
2794		printk(KERN_ERR "Umm, you don't have the default dir item, "
2795		       "this isn't going to work\n");
2796		return -ENOENT;
 
2797	}
2798
2799	btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
2800	btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
2801	btrfs_mark_buffer_dirty(path->nodes[0]);
 
 
 
 
 
 
2802	btrfs_free_path(path);
2803
2804	disk_super = root->fs_info->super_copy;
2805	features = btrfs_super_incompat_flags(disk_super);
2806	if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
2807		features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
2808		btrfs_set_super_incompat_flags(disk_super, features);
2809	}
2810	btrfs_end_transaction(trans, root);
2811
2812	return 0;
2813}
2814
2815static void get_block_group_info(struct list_head *groups_list,
2816				 struct btrfs_ioctl_space_info *space)
2817{
2818	struct btrfs_block_group_cache *block_group;
2819
2820	space->total_bytes = 0;
2821	space->used_bytes = 0;
2822	space->flags = 0;
2823	list_for_each_entry(block_group, groups_list, list) {
2824		space->flags = block_group->flags;
2825		space->total_bytes += block_group->key.offset;
2826		space->used_bytes +=
2827			btrfs_block_group_used(&block_group->item);
2828	}
2829}
2830
2831long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
 
2832{
2833	struct btrfs_ioctl_space_args space_args;
2834	struct btrfs_ioctl_space_info space;
2835	struct btrfs_ioctl_space_info *dest;
2836	struct btrfs_ioctl_space_info *dest_orig;
2837	struct btrfs_ioctl_space_info __user *user_dest;
2838	struct btrfs_space_info *info;
2839	u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
2840		       BTRFS_BLOCK_GROUP_SYSTEM,
2841		       BTRFS_BLOCK_GROUP_METADATA,
2842		       BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
 
 
2843	int num_types = 4;
2844	int alloc_size;
2845	int ret = 0;
2846	u64 slot_count = 0;
2847	int i, c;
2848
2849	if (copy_from_user(&space_args,
2850			   (struct btrfs_ioctl_space_args __user *)arg,
2851			   sizeof(space_args)))
2852		return -EFAULT;
2853
2854	for (i = 0; i < num_types; i++) {
2855		struct btrfs_space_info *tmp;
2856
2857		info = NULL;
2858		rcu_read_lock();
2859		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2860					list) {
2861			if (tmp->flags == types[i]) {
2862				info = tmp;
2863				break;
2864			}
2865		}
2866		rcu_read_unlock();
2867
2868		if (!info)
2869			continue;
2870
2871		down_read(&info->groups_sem);
2872		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2873			if (!list_empty(&info->block_groups[c]))
2874				slot_count++;
2875		}
2876		up_read(&info->groups_sem);
2877	}
2878
 
 
 
 
 
2879	/* space_slots == 0 means they are asking for a count */
2880	if (space_args.space_slots == 0) {
2881		space_args.total_spaces = slot_count;
2882		goto out;
2883	}
2884
2885	slot_count = min_t(u64, space_args.space_slots, slot_count);
2886
2887	alloc_size = sizeof(*dest) * slot_count;
2888
2889	/* we generally have at most 6 or so space infos, one for each raid
2890	 * level.  So, a whole page should be more than enough for everyone
2891	 */
2892	if (alloc_size > PAGE_CACHE_SIZE)
2893		return -ENOMEM;
2894
2895	space_args.total_spaces = 0;
2896	dest = kmalloc(alloc_size, GFP_NOFS);
2897	if (!dest)
2898		return -ENOMEM;
2899	dest_orig = dest;
2900
2901	/* now we have a buffer to copy into */
2902	for (i = 0; i < num_types; i++) {
2903		struct btrfs_space_info *tmp;
2904
2905		if (!slot_count)
2906			break;
2907
2908		info = NULL;
2909		rcu_read_lock();
2910		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
2911					list) {
2912			if (tmp->flags == types[i]) {
2913				info = tmp;
2914				break;
2915			}
2916		}
2917		rcu_read_unlock();
2918
2919		if (!info)
2920			continue;
2921		down_read(&info->groups_sem);
2922		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
2923			if (!list_empty(&info->block_groups[c])) {
2924				get_block_group_info(&info->block_groups[c],
2925						     &space);
2926				memcpy(dest, &space, sizeof(space));
2927				dest++;
2928				space_args.total_spaces++;
2929				slot_count--;
2930			}
2931			if (!slot_count)
2932				break;
2933		}
2934		up_read(&info->groups_sem);
2935	}
2936
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2937	user_dest = (struct btrfs_ioctl_space_info __user *)
2938		(arg + sizeof(struct btrfs_ioctl_space_args));
2939
2940	if (copy_to_user(user_dest, dest_orig, alloc_size))
2941		ret = -EFAULT;
2942
2943	kfree(dest_orig);
2944out:
2945	if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
2946		ret = -EFAULT;
2947
2948	return ret;
2949}
2950
2951/*
2952 * there are many ways the trans_start and trans_end ioctls can lead
2953 * to deadlocks.  They should only be used by applications that
2954 * basically own the machine, and have a very in depth understanding
2955 * of all the possible deadlocks and enospc problems.
2956 */
2957long btrfs_ioctl_trans_end(struct file *file)
2958{
2959	struct inode *inode = fdentry(file)->d_inode;
2960	struct btrfs_root *root = BTRFS_I(inode)->root;
2961	struct btrfs_trans_handle *trans;
 
2962
2963	trans = file->private_data;
2964	if (!trans)
2965		return -EINVAL;
2966	file->private_data = NULL;
2967
2968	btrfs_end_transaction(trans, root);
2969
2970	atomic_dec(&root->fs_info->open_ioctl_trans);
2971
2972	mnt_drop_write_file(file);
2973	return 0;
2974}
2975
2976static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
2977{
2978	struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
2979	struct btrfs_trans_handle *trans;
2980	u64 transid;
2981	int ret;
2982
2983	trans = btrfs_start_transaction(root, 0);
2984	if (IS_ERR(trans))
2985		return PTR_ERR(trans);
2986	transid = trans->transid;
2987	ret = btrfs_commit_transaction_async(trans, root, 0);
2988	if (ret) {
2989		btrfs_end_transaction(trans, root);
2990		return ret;
2991	}
2992
2993	if (argp)
2994		if (copy_to_user(argp, &transid, sizeof(transid)))
2995			return -EFAULT;
2996	return 0;
2997}
2998
2999static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
 
3000{
3001	struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
3002	u64 transid;
3003
3004	if (argp) {
3005		if (copy_from_user(&transid, argp, sizeof(transid)))
3006			return -EFAULT;
3007	} else {
3008		transid = 0;  /* current trans */
3009	}
3010	return btrfs_wait_for_commit(root, transid);
3011}
3012
3013static long btrfs_ioctl_scrub(struct btrfs_root *root, void __user *arg)
3014{
 
 
3015	int ret;
3016	struct btrfs_ioctl_scrub_args *sa;
3017
3018	if (!capable(CAP_SYS_ADMIN))
3019		return -EPERM;
3020
 
 
 
 
 
3021	sa = memdup_user(arg, sizeof(*sa));
3022	if (IS_ERR(sa))
3023		return PTR_ERR(sa);
3024
3025	ret = btrfs_scrub_dev(root, sa->devid, sa->start, sa->end,
3026			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY);
 
 
 
 
 
 
 
3027
 
 
 
 
 
 
 
 
 
 
 
 
3028	if (copy_to_user(arg, sa, sizeof(*sa)))
3029		ret = -EFAULT;
3030
 
 
 
3031	kfree(sa);
3032	return ret;
3033}
3034
3035static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
3036{
3037	if (!capable(CAP_SYS_ADMIN))
3038		return -EPERM;
3039
3040	return btrfs_scrub_cancel(root);
3041}
3042
3043static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
3044				       void __user *arg)
3045{
3046	struct btrfs_ioctl_scrub_args *sa;
3047	int ret;
3048
3049	if (!capable(CAP_SYS_ADMIN))
3050		return -EPERM;
3051
3052	sa = memdup_user(arg, sizeof(*sa));
3053	if (IS_ERR(sa))
3054		return PTR_ERR(sa);
3055
3056	ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);
3057
3058	if (copy_to_user(arg, sa, sizeof(*sa)))
3059		ret = -EFAULT;
3060
3061	kfree(sa);
3062	return ret;
3063}
3064
3065static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3066				      void __user *arg, int reset_after_read)
3067{
3068	struct btrfs_ioctl_get_dev_stats *sa;
3069	int ret;
3070
3071	if (reset_after_read && !capable(CAP_SYS_ADMIN))
3072		return -EPERM;
3073
3074	sa = memdup_user(arg, sizeof(*sa));
3075	if (IS_ERR(sa))
3076		return PTR_ERR(sa);
3077
3078	ret = btrfs_get_dev_stats(root, sa, reset_after_read);
 
 
 
 
 
3079
3080	if (copy_to_user(arg, sa, sizeof(*sa)))
3081		ret = -EFAULT;
3082
3083	kfree(sa);
3084	return ret;
3085}
3086
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3087static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
3088{
3089	int ret = 0;
3090	int i;
3091	u64 rel_ptr;
3092	int size;
3093	struct btrfs_ioctl_ino_path_args *ipa = NULL;
3094	struct inode_fs_paths *ipath = NULL;
3095	struct btrfs_path *path;
3096
3097	if (!capable(CAP_SYS_ADMIN))
3098		return -EPERM;
3099
3100	path = btrfs_alloc_path();
3101	if (!path) {
3102		ret = -ENOMEM;
3103		goto out;
3104	}
3105
3106	ipa = memdup_user(arg, sizeof(*ipa));
3107	if (IS_ERR(ipa)) {
3108		ret = PTR_ERR(ipa);
3109		ipa = NULL;
3110		goto out;
3111	}
3112
3113	size = min_t(u32, ipa->size, 4096);
3114	ipath = init_ipath(size, root, path);
3115	if (IS_ERR(ipath)) {
3116		ret = PTR_ERR(ipath);
3117		ipath = NULL;
3118		goto out;
3119	}
3120
3121	ret = paths_from_inode(ipa->inum, ipath);
3122	if (ret < 0)
3123		goto out;
3124
3125	for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3126		rel_ptr = ipath->fspath->val[i] -
3127			  (u64)(unsigned long)ipath->fspath->val;
3128		ipath->fspath->val[i] = rel_ptr;
3129	}
3130
3131	ret = copy_to_user((void *)(unsigned long)ipa->fspath,
3132			   (void *)(unsigned long)ipath->fspath, size);
 
 
3133	if (ret) {
3134		ret = -EFAULT;
3135		goto out;
3136	}
3137
3138out:
3139	btrfs_free_path(path);
3140	free_ipath(ipath);
3141	kfree(ipa);
3142
3143	return ret;
3144}
3145
3146static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
3147{
3148	struct btrfs_data_container *inodes = ctx;
3149	const size_t c = 3 * sizeof(u64);
3150
3151	if (inodes->bytes_left >= c) {
3152		inodes->bytes_left -= c;
3153		inodes->val[inodes->elem_cnt] = inum;
3154		inodes->val[inodes->elem_cnt + 1] = offset;
3155		inodes->val[inodes->elem_cnt + 2] = root;
3156		inodes->elem_cnt += 3;
3157	} else {
3158		inodes->bytes_missing += c - inodes->bytes_left;
3159		inodes->bytes_left = 0;
3160		inodes->elem_missed += 3;
3161	}
3162
3163	return 0;
3164}
3165
3166static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
3167					void __user *arg)
3168{
3169	int ret = 0;
3170	int size;
3171	u64 extent_item_pos;
3172	struct btrfs_ioctl_logical_ino_args *loi;
3173	struct btrfs_data_container *inodes = NULL;
3174	struct btrfs_path *path = NULL;
3175	struct btrfs_key key;
3176
3177	if (!capable(CAP_SYS_ADMIN))
3178		return -EPERM;
3179
3180	loi = memdup_user(arg, sizeof(*loi));
3181	if (IS_ERR(loi)) {
3182		ret = PTR_ERR(loi);
3183		loi = NULL;
3184		goto out;
3185	}
3186
3187	path = btrfs_alloc_path();
3188	if (!path) {
3189		ret = -ENOMEM;
3190		goto out;
 
 
 
 
 
 
 
 
 
 
 
 
3191	}
3192
3193	size = min_t(u32, loi->size, 4096);
3194	inodes = init_data_container(size);
3195	if (IS_ERR(inodes)) {
3196		ret = PTR_ERR(inodes);
3197		inodes = NULL;
 
 
 
 
 
3198		goto out;
3199	}
3200
3201	ret = extent_from_logical(root->fs_info, loi->logical, path, &key);
3202	btrfs_release_path(path);
3203
3204	if (ret & BTRFS_EXTENT_FLAG_TREE_BLOCK)
3205		ret = -ENOENT;
3206	if (ret < 0)
3207		goto out;
3208
3209	extent_item_pos = loi->logical - key.objectid;
3210	ret = iterate_extent_inodes(root->fs_info, key.objectid,
3211					extent_item_pos, 0, build_ino_list,
3212					inodes);
3213
3214	if (ret < 0)
3215		goto out;
3216
3217	ret = copy_to_user((void *)(unsigned long)loi->inodes,
3218			   (void *)(unsigned long)inodes, size);
3219	if (ret)
3220		ret = -EFAULT;
3221
3222out:
3223	btrfs_free_path(path);
3224	kfree(inodes);
3225	kfree(loi);
3226
3227	return ret;
3228}
3229
3230void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3231			       struct btrfs_ioctl_balance_args *bargs)
3232{
3233	struct btrfs_balance_control *bctl = fs_info->balance_ctl;
3234
3235	bargs->flags = bctl->flags;
3236
3237	if (atomic_read(&fs_info->balance_running))
3238		bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
3239	if (atomic_read(&fs_info->balance_pause_req))
3240		bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3241	if (atomic_read(&fs_info->balance_cancel_req))
3242		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3243
3244	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
3245	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
3246	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3247
3248	if (lock) {
3249		spin_lock(&fs_info->balance_lock);
3250		memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
3251		spin_unlock(&fs_info->balance_lock);
3252	} else {
3253		memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3254	}
 
 
 
 
 
3255}
3256
3257static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3258{
3259	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
3260	struct btrfs_fs_info *fs_info = root->fs_info;
3261	struct btrfs_ioctl_balance_args *bargs;
3262	struct btrfs_balance_control *bctl;
 
3263	int ret;
3264
3265	if (!capable(CAP_SYS_ADMIN))
3266		return -EPERM;
3267
3268	if (fs_info->sb->s_flags & MS_RDONLY)
3269		return -EROFS;
 
 
 
 
 
 
 
 
3270
3271	ret = mnt_want_write(file->f_path.mnt);
3272	if (ret)
3273		return ret;
3274
3275	mutex_lock(&fs_info->volume_mutex);
3276	mutex_lock(&fs_info->balance_mutex);
3277
3278	if (arg) {
3279		bargs = memdup_user(arg, sizeof(*bargs));
3280		if (IS_ERR(bargs)) {
3281			ret = PTR_ERR(bargs);
3282			goto out;
3283		}
3284
3285		if (bargs->flags & BTRFS_BALANCE_RESUME) {
3286			if (!fs_info->balance_ctl) {
3287				ret = -ENOTCONN;
3288				goto out_bargs;
3289			}
3290
3291			bctl = fs_info->balance_ctl;
3292			spin_lock(&fs_info->balance_lock);
3293			bctl->flags |= BTRFS_BALANCE_RESUME;
3294			spin_unlock(&fs_info->balance_lock);
3295
3296			goto do_balance;
3297		}
3298	} else {
3299		bargs = NULL;
3300	}
3301
3302	if (fs_info->balance_ctl) {
3303		ret = -EINPROGRESS;
3304		goto out_bargs;
3305	}
3306
3307	bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
3308	if (!bctl) {
3309		ret = -ENOMEM;
3310		goto out_bargs;
3311	}
3312
3313	bctl->fs_info = fs_info;
3314	if (arg) {
3315		memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
3316		memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
3317		memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));
3318
3319		bctl->flags = bargs->flags;
3320	} else {
3321		/* balance everything - no filters */
3322		bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3323	}
3324
 
3325do_balance:
3326	ret = btrfs_balance(bctl, bargs);
3327	/*
3328	 * bctl is freed in __cancel_balance or in free_fs_info if
3329	 * restriper was paused all the way until unmount
 
 
3330	 */
3331	if (arg) {
 
 
 
 
 
3332		if (copy_to_user(arg, bargs, sizeof(*bargs)))
3333			ret = -EFAULT;
3334	}
3335
3336out_bargs:
 
 
 
 
 
 
3337	kfree(bargs);
3338out:
3339	mutex_unlock(&fs_info->balance_mutex);
3340	mutex_unlock(&fs_info->volume_mutex);
3341	mnt_drop_write(file->f_path.mnt);
3342	return ret;
3343}
3344
3345static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
3346{
3347	if (!capable(CAP_SYS_ADMIN))
3348		return -EPERM;
3349
3350	switch (cmd) {
3351	case BTRFS_BALANCE_CTL_PAUSE:
3352		return btrfs_pause_balance(root->fs_info);
3353	case BTRFS_BALANCE_CTL_CANCEL:
3354		return btrfs_cancel_balance(root->fs_info);
3355	}
3356
3357	return -EINVAL;
3358}
3359
3360static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
3361					 void __user *arg)
3362{
3363	struct btrfs_fs_info *fs_info = root->fs_info;
3364	struct btrfs_ioctl_balance_args *bargs;
3365	int ret = 0;
3366
3367	if (!capable(CAP_SYS_ADMIN))
3368		return -EPERM;
3369
3370	mutex_lock(&fs_info->balance_mutex);
3371	if (!fs_info->balance_ctl) {
3372		ret = -ENOTCONN;
3373		goto out;
3374	}
3375
3376	bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
3377	if (!bargs) {
3378		ret = -ENOMEM;
3379		goto out;
3380	}
3381
3382	update_ioctl_balance_args(fs_info, 1, bargs);
3383
3384	if (copy_to_user(arg, bargs, sizeof(*bargs)))
3385		ret = -EFAULT;
3386
3387	kfree(bargs);
3388out:
3389	mutex_unlock(&fs_info->balance_mutex);
3390	return ret;
3391}
3392
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3393long btrfs_ioctl(struct file *file, unsigned int
3394		cmd, unsigned long arg)
3395{
3396	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
 
 
3397	void __user *argp = (void __user *)arg;
3398
3399	switch (cmd) {
3400	case FS_IOC_GETFLAGS:
3401		return btrfs_ioctl_getflags(file, argp);
3402	case FS_IOC_SETFLAGS:
3403		return btrfs_ioctl_setflags(file, argp);
3404	case FS_IOC_GETVERSION:
3405		return btrfs_ioctl_getversion(file, argp);
 
 
 
 
3406	case FITRIM:
3407		return btrfs_ioctl_fitrim(file, argp);
3408	case BTRFS_IOC_SNAP_CREATE:
3409		return btrfs_ioctl_snap_create(file, argp, 0);
3410	case BTRFS_IOC_SNAP_CREATE_V2:
3411		return btrfs_ioctl_snap_create_v2(file, argp, 0);
3412	case BTRFS_IOC_SUBVOL_CREATE:
3413		return btrfs_ioctl_snap_create(file, argp, 1);
 
 
3414	case BTRFS_IOC_SNAP_DESTROY:
3415		return btrfs_ioctl_snap_destroy(file, argp);
 
 
3416	case BTRFS_IOC_SUBVOL_GETFLAGS:
3417		return btrfs_ioctl_subvol_getflags(file, argp);
3418	case BTRFS_IOC_SUBVOL_SETFLAGS:
3419		return btrfs_ioctl_subvol_setflags(file, argp);
3420	case BTRFS_IOC_DEFAULT_SUBVOL:
3421		return btrfs_ioctl_default_subvol(file, argp);
3422	case BTRFS_IOC_DEFRAG:
3423		return btrfs_ioctl_defrag(file, NULL);
3424	case BTRFS_IOC_DEFRAG_RANGE:
3425		return btrfs_ioctl_defrag(file, argp);
3426	case BTRFS_IOC_RESIZE:
3427		return btrfs_ioctl_resize(root, argp);
3428	case BTRFS_IOC_ADD_DEV:
3429		return btrfs_ioctl_add_dev(root, argp);
3430	case BTRFS_IOC_RM_DEV:
3431		return btrfs_ioctl_rm_dev(root, argp);
 
 
3432	case BTRFS_IOC_FS_INFO:
3433		return btrfs_ioctl_fs_info(root, argp);
3434	case BTRFS_IOC_DEV_INFO:
3435		return btrfs_ioctl_dev_info(root, argp);
3436	case BTRFS_IOC_BALANCE:
3437		return btrfs_ioctl_balance(file, NULL);
3438	case BTRFS_IOC_CLONE:
3439		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
3440	case BTRFS_IOC_CLONE_RANGE:
3441		return btrfs_ioctl_clone_range(file, argp);
3442	case BTRFS_IOC_TRANS_START:
3443		return btrfs_ioctl_trans_start(file);
3444	case BTRFS_IOC_TRANS_END:
3445		return btrfs_ioctl_trans_end(file);
3446	case BTRFS_IOC_TREE_SEARCH:
3447		return btrfs_ioctl_tree_search(file, argp);
 
 
3448	case BTRFS_IOC_INO_LOOKUP:
3449		return btrfs_ioctl_ino_lookup(file, argp);
3450	case BTRFS_IOC_INO_PATHS:
3451		return btrfs_ioctl_ino_to_path(root, argp);
3452	case BTRFS_IOC_LOGICAL_INO:
3453		return btrfs_ioctl_logical_to_ino(root, argp);
 
 
3454	case BTRFS_IOC_SPACE_INFO:
3455		return btrfs_ioctl_space_info(root, argp);
3456	case BTRFS_IOC_SYNC:
3457		btrfs_sync_fs(file->f_dentry->d_sb, 1);
3458		return 0;
 
 
 
 
 
 
 
 
 
 
 
 
3459	case BTRFS_IOC_START_SYNC:
3460		return btrfs_ioctl_start_sync(file, argp);
3461	case BTRFS_IOC_WAIT_SYNC:
3462		return btrfs_ioctl_wait_sync(file, argp);
3463	case BTRFS_IOC_SCRUB:
3464		return btrfs_ioctl_scrub(root, argp);
3465	case BTRFS_IOC_SCRUB_CANCEL:
3466		return btrfs_ioctl_scrub_cancel(root, argp);
3467	case BTRFS_IOC_SCRUB_PROGRESS:
3468		return btrfs_ioctl_scrub_progress(root, argp);
3469	case BTRFS_IOC_BALANCE_V2:
3470		return btrfs_ioctl_balance(file, argp);
3471	case BTRFS_IOC_BALANCE_CTL:
3472		return btrfs_ioctl_balance_ctl(root, arg);
3473	case BTRFS_IOC_BALANCE_PROGRESS:
3474		return btrfs_ioctl_balance_progress(root, argp);
 
 
 
 
 
 
 
 
 
 
 
 
3475	case BTRFS_IOC_GET_DEV_STATS:
3476		return btrfs_ioctl_get_dev_stats(root, argp, 0);
3477	case BTRFS_IOC_GET_AND_RESET_DEV_STATS:
3478		return btrfs_ioctl_get_dev_stats(root, argp, 1);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3479	}
3480
3481	return -ENOTTY;
3482}