ioctl.c 108.1 KB
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/*
 * Copyright (C) 2007 Oracle.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include <linux/kernel.h>
#include <linux/bio.h>
#include <linux/buffer_head.h>
#include <linux/file.h>
#include <linux/fs.h>
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#include <linux/fsnotify.h>
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#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/string.h>
#include <linux/backing-dev.h>
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#include <linux/mount.h>
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#include <linux/mpage.h>
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#include <linux/namei.h>
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#include <linux/swap.h>
#include <linux/writeback.h>
#include <linux/statfs.h>
#include <linux/compat.h>
#include <linux/bit_spinlock.h>
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#include <linux/security.h>
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#include <linux/xattr.h>
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#include <linux/vmalloc.h>
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#include <linux/slab.h>
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#include <linux/blkdev.h>
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#include <linux/uuid.h>
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#include <linux/btrfs.h>
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#include <linux/uaccess.h>
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#include "compat.h"
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#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.h"
#include "print-tree.h"
#include "volumes.h"
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#include "locking.h"
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#include "inode-map.h"
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#include "backref.h"
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#include "rcu-string.h"
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#include "send.h"
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#include "dev-replace.h"
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static int btrfs_clone(struct inode *src, struct inode *inode,
		       u64 off, u64 olen, u64 olen_aligned, u64 destoff);

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/* Mask out flags that are inappropriate for the given type of inode. */
static inline __u32 btrfs_mask_flags(umode_t mode, __u32 flags)
{
	if (S_ISDIR(mode))
		return flags;
	else if (S_ISREG(mode))
		return flags & ~FS_DIRSYNC_FL;
	else
		return flags & (FS_NODUMP_FL | FS_NOATIME_FL);
}

/*
 * Export inode flags to the format expected by the FS_IOC_GETFLAGS ioctl.
 */
static unsigned int btrfs_flags_to_ioctl(unsigned int flags)
{
	unsigned int iflags = 0;

	if (flags & BTRFS_INODE_SYNC)
		iflags |= FS_SYNC_FL;
	if (flags & BTRFS_INODE_IMMUTABLE)
		iflags |= FS_IMMUTABLE_FL;
	if (flags & BTRFS_INODE_APPEND)
		iflags |= FS_APPEND_FL;
	if (flags & BTRFS_INODE_NODUMP)
		iflags |= FS_NODUMP_FL;
	if (flags & BTRFS_INODE_NOATIME)
		iflags |= FS_NOATIME_FL;
	if (flags & BTRFS_INODE_DIRSYNC)
		iflags |= FS_DIRSYNC_FL;
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	if (flags & BTRFS_INODE_NODATACOW)
		iflags |= FS_NOCOW_FL;

	if ((flags & BTRFS_INODE_COMPRESS) && !(flags & BTRFS_INODE_NOCOMPRESS))
		iflags |= FS_COMPR_FL;
	else if (flags & BTRFS_INODE_NOCOMPRESS)
		iflags |= FS_NOCOMP_FL;
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	return iflags;
}

/*
 * Update inode->i_flags based on the btrfs internal flags.
 */
void btrfs_update_iflags(struct inode *inode)
{
	struct btrfs_inode *ip = BTRFS_I(inode);

	inode->i_flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC);

	if (ip->flags & BTRFS_INODE_SYNC)
		inode->i_flags |= S_SYNC;
	if (ip->flags & BTRFS_INODE_IMMUTABLE)
		inode->i_flags |= S_IMMUTABLE;
	if (ip->flags & BTRFS_INODE_APPEND)
		inode->i_flags |= S_APPEND;
	if (ip->flags & BTRFS_INODE_NOATIME)
		inode->i_flags |= S_NOATIME;
	if (ip->flags & BTRFS_INODE_DIRSYNC)
		inode->i_flags |= S_DIRSYNC;
}

/*
 * Inherit flags from the parent inode.
 *
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 * Currently only the compression flags and the cow flags are inherited.
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 */
void btrfs_inherit_iflags(struct inode *inode, struct inode *dir)
{
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	unsigned int flags;

	if (!dir)
		return;

	flags = BTRFS_I(dir)->flags;
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	if (flags & BTRFS_INODE_NOCOMPRESS) {
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_COMPRESS;
		BTRFS_I(inode)->flags |= BTRFS_INODE_NOCOMPRESS;
	} else if (flags & BTRFS_INODE_COMPRESS) {
		BTRFS_I(inode)->flags &= ~BTRFS_INODE_NOCOMPRESS;
		BTRFS_I(inode)->flags |= BTRFS_INODE_COMPRESS;
	}

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	if (flags & BTRFS_INODE_NODATACOW) {
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		BTRFS_I(inode)->flags |= BTRFS_INODE_NODATACOW;
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		if (S_ISREG(inode->i_mode))
			BTRFS_I(inode)->flags |= BTRFS_INODE_NODATASUM;
	}
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	btrfs_update_iflags(inode);
}

static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
{
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	struct btrfs_inode *ip = BTRFS_I(file_inode(file));
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	unsigned int flags = btrfs_flags_to_ioctl(ip->flags);

	if (copy_to_user(arg, &flags, sizeof(flags)))
		return -EFAULT;
	return 0;
}

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static int check_flags(unsigned int flags)
{
	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
		      FS_NOATIME_FL | FS_NODUMP_FL | \
		      FS_SYNC_FL | FS_DIRSYNC_FL | \
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		      FS_NOCOMP_FL | FS_COMPR_FL |
		      FS_NOCOW_FL))
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		return -EOPNOTSUPP;

	if ((flags & FS_NOCOMP_FL) && (flags & FS_COMPR_FL))
		return -EINVAL;

	return 0;
}

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static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
{
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	struct inode *inode = file_inode(file);
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	struct btrfs_inode *ip = BTRFS_I(inode);
	struct btrfs_root *root = ip->root;
	struct btrfs_trans_handle *trans;
	unsigned int flags, oldflags;
	int ret;
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	u64 ip_oldflags;
	unsigned int i_oldflags;
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	umode_t mode;
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	if (btrfs_root_readonly(root))
		return -EROFS;

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	if (copy_from_user(&flags, arg, sizeof(flags)))
		return -EFAULT;

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	ret = check_flags(flags);
	if (ret)
		return ret;
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	if (!inode_owner_or_capable(inode))
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		return -EACCES;

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	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

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	mutex_lock(&inode->i_mutex);

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	ip_oldflags = ip->flags;
	i_oldflags = inode->i_flags;
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	mode = inode->i_mode;
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	flags = btrfs_mask_flags(inode->i_mode, flags);
	oldflags = btrfs_flags_to_ioctl(ip->flags);
	if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) {
		if (!capable(CAP_LINUX_IMMUTABLE)) {
			ret = -EPERM;
			goto out_unlock;
		}
	}

	if (flags & FS_SYNC_FL)
		ip->flags |= BTRFS_INODE_SYNC;
	else
		ip->flags &= ~BTRFS_INODE_SYNC;
	if (flags & FS_IMMUTABLE_FL)
		ip->flags |= BTRFS_INODE_IMMUTABLE;
	else
		ip->flags &= ~BTRFS_INODE_IMMUTABLE;
	if (flags & FS_APPEND_FL)
		ip->flags |= BTRFS_INODE_APPEND;
	else
		ip->flags &= ~BTRFS_INODE_APPEND;
	if (flags & FS_NODUMP_FL)
		ip->flags |= BTRFS_INODE_NODUMP;
	else
		ip->flags &= ~BTRFS_INODE_NODUMP;
	if (flags & FS_NOATIME_FL)
		ip->flags |= BTRFS_INODE_NOATIME;
	else
		ip->flags &= ~BTRFS_INODE_NOATIME;
	if (flags & FS_DIRSYNC_FL)
		ip->flags |= BTRFS_INODE_DIRSYNC;
	else
		ip->flags &= ~BTRFS_INODE_DIRSYNC;
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	if (flags & FS_NOCOW_FL) {
		if (S_ISREG(mode)) {
			/*
			 * It's safe to turn csums off here, no extents exist.
			 * Otherwise we want the flag to reflect the real COW
			 * status of the file and will not set it.
			 */
			if (inode->i_size == 0)
				ip->flags |= BTRFS_INODE_NODATACOW
					   | BTRFS_INODE_NODATASUM;
		} else {
			ip->flags |= BTRFS_INODE_NODATACOW;
		}
	} else {
		/*
		 * Revert back under same assuptions as above
		 */
		if (S_ISREG(mode)) {
			if (inode->i_size == 0)
				ip->flags &= ~(BTRFS_INODE_NODATACOW
				             | BTRFS_INODE_NODATASUM);
		} else {
			ip->flags &= ~BTRFS_INODE_NODATACOW;
		}
	}
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	/*
	 * The COMPRESS flag can only be changed by users, while the NOCOMPRESS
	 * flag may be changed automatically if compression code won't make
	 * things smaller.
	 */
	if (flags & FS_NOCOMP_FL) {
		ip->flags &= ~BTRFS_INODE_COMPRESS;
		ip->flags |= BTRFS_INODE_NOCOMPRESS;
	} else if (flags & FS_COMPR_FL) {
		ip->flags |= BTRFS_INODE_COMPRESS;
		ip->flags &= ~BTRFS_INODE_NOCOMPRESS;
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	} else {
		ip->flags &= ~(BTRFS_INODE_COMPRESS | BTRFS_INODE_NOCOMPRESS);
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	}
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	trans = btrfs_start_transaction(root, 1);
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	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_drop;
	}
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	btrfs_update_iflags(inode);
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	inode_inc_iversion(inode);
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	inode->i_ctime = CURRENT_TIME;
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	ret = btrfs_update_inode(trans, root, inode);

	btrfs_end_transaction(trans, root);
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 out_drop:
	if (ret) {
		ip->flags = ip_oldflags;
		inode->i_flags = i_oldflags;
	}
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 out_unlock:
	mutex_unlock(&inode->i_mutex);
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	mnt_drop_write_file(file);
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	return ret;
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}

static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
{
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	struct inode *inode = file_inode(file);
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	return put_user(inode->i_generation, arg);
}
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static noinline int btrfs_ioctl_fitrim(struct file *file, void __user *arg)
{
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	struct btrfs_fs_info *fs_info = btrfs_sb(fdentry(file)->d_sb);
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	struct btrfs_device *device;
	struct request_queue *q;
	struct fstrim_range range;
	u64 minlen = ULLONG_MAX;
	u64 num_devices = 0;
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	u64 total_bytes = btrfs_super_total_bytes(fs_info->super_copy);
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	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

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	rcu_read_lock();
	list_for_each_entry_rcu(device, &fs_info->fs_devices->devices,
				dev_list) {
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		if (!device->bdev)
			continue;
		q = bdev_get_queue(device->bdev);
		if (blk_queue_discard(q)) {
			num_devices++;
			minlen = min((u64)q->limits.discard_granularity,
				     minlen);
		}
	}
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	rcu_read_unlock();
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	if (!num_devices)
		return -EOPNOTSUPP;
	if (copy_from_user(&range, arg, sizeof(range)))
		return -EFAULT;
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	if (range.start > total_bytes ||
	    range.len < fs_info->sb->s_blocksize)
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		return -EINVAL;
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358
	range.len = min(range.len, total_bytes - range.start);
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	range.minlen = max(range.minlen, minlen);
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	ret = btrfs_trim_fs(fs_info->tree_root, &range);
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	if (ret < 0)
		return ret;

	if (copy_to_user(arg, &range, sizeof(range)))
		return -EFAULT;

	return 0;
}

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int btrfs_is_empty_uuid(u8 *uuid)
{
	static char empty_uuid[BTRFS_UUID_SIZE] = {0};

	return !memcmp(uuid, empty_uuid, BTRFS_UUID_SIZE);
}

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static noinline int create_subvol(struct inode *dir,
378
				  struct dentry *dentry,
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				  char *name, int namelen,
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				  u64 *async_transid,
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				  struct btrfs_qgroup_inherit *inherit)
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{
	struct btrfs_trans_handle *trans;
	struct btrfs_key key;
	struct btrfs_root_item root_item;
	struct btrfs_inode_item *inode_item;
	struct extent_buffer *leaf;
388
	struct btrfs_root *root = BTRFS_I(dir)->root;
389
	struct btrfs_root *new_root;
390
	struct btrfs_block_rsv block_rsv;
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	struct timespec cur_time = CURRENT_TIME;
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	int ret;
	int err;
	u64 objectid;
	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
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	u64 index = 0;
397
	u64 qgroup_reserved;
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	uuid_le new_uuid;
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400
	ret = btrfs_find_free_objectid(root->fs_info->tree_root, &objectid);
401
	if (ret)
402
		return ret;
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404
	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
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	/*
406 407
	 * The same as the snapshot creation, please see the comment
	 * of create_snapshot().
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	 */
409
	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
410
					       8, &qgroup_reserved, false);
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	if (ret)
		return ret;

	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
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422
	ret = btrfs_qgroup_inherit(trans, root->fs_info, 0, objectid, inherit);
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	if (ret)
		goto fail;

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	leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
427
				      0, objectid, NULL, 0, 0, 0);
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	if (IS_ERR(leaf)) {
		ret = PTR_ERR(leaf);
		goto fail;
	}
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433
	memset_extent_buffer(leaf, 0, 0, sizeof(struct btrfs_header));
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	btrfs_set_header_bytenr(leaf, leaf->start);
	btrfs_set_header_generation(leaf, trans->transid);
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	btrfs_set_header_backref_rev(leaf, BTRFS_MIXED_BACKREF_REV);
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	btrfs_set_header_owner(leaf, objectid);

439
	write_extent_buffer(leaf, root->fs_info->fsid, btrfs_header_fsid(leaf),
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			    BTRFS_FSID_SIZE);
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	write_extent_buffer(leaf, root->fs_info->chunk_tree_uuid,
			    (unsigned long)btrfs_header_chunk_tree_uuid(leaf),
			    BTRFS_UUID_SIZE);
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	btrfs_mark_buffer_dirty(leaf);

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	memset(&root_item, 0, sizeof(root_item));

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	inode_item = &root_item.inode;
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	btrfs_set_stack_inode_generation(inode_item, 1);
	btrfs_set_stack_inode_size(inode_item, 3);
	btrfs_set_stack_inode_nlink(inode_item, 1);
	btrfs_set_stack_inode_nbytes(inode_item, root->leafsize);
	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
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	btrfs_set_root_flags(&root_item, 0);
	btrfs_set_root_limit(&root_item, 0);
	btrfs_set_stack_inode_flags(inode_item, BTRFS_INODE_ROOT_ITEM_INIT);
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	btrfs_set_root_bytenr(&root_item, leaf->start);
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	btrfs_set_root_generation(&root_item, trans->transid);
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	btrfs_set_root_level(&root_item, 0);
	btrfs_set_root_refs(&root_item, 1);
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	btrfs_set_root_used(&root_item, leaf->len);
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	btrfs_set_root_last_snapshot(&root_item, 0);
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	btrfs_set_root_generation_v2(&root_item,
			btrfs_root_generation(&root_item));
	uuid_le_gen(&new_uuid);
	memcpy(root_item.uuid, new_uuid.b, BTRFS_UUID_SIZE);
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	btrfs_set_stack_timespec_sec(&root_item.otime, cur_time.tv_sec);
	btrfs_set_stack_timespec_nsec(&root_item.otime, cur_time.tv_nsec);
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	root_item.ctime = root_item.otime;
	btrfs_set_root_ctransid(&root_item, trans->transid);
	btrfs_set_root_otransid(&root_item, trans->transid);
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	btrfs_tree_unlock(leaf);
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	free_extent_buffer(leaf);
	leaf = NULL;

	btrfs_set_root_dirid(&root_item, new_dirid);

	key.objectid = objectid;
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	key.offset = 0;
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	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
				&root_item);
	if (ret)
		goto fail;

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	key.offset = (u64)-1;
	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
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	if (IS_ERR(new_root)) {
		btrfs_abort_transaction(trans, root, PTR_ERR(new_root));
		ret = PTR_ERR(new_root);
		goto fail;
	}
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	btrfs_record_root_in_trans(trans, new_root);

500
	ret = btrfs_create_subvol_root(trans, new_root, new_dirid);
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	if (ret) {
		/* We potentially lose an unused inode item here */
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		btrfs_abort_transaction(trans, root, ret);
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		goto fail;
	}

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	/*
	 * insert the directory item
	 */
510
	ret = btrfs_set_inode_index(dir, &index);
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	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
		goto fail;
	}
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	ret = btrfs_insert_dir_item(trans, root,
517
				    name, namelen, dir, &key,
518
				    BTRFS_FT_DIR, index);
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	if (ret) {
		btrfs_abort_transaction(trans, root, ret);
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		goto fail;
522
	}
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	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
	ret = btrfs_update_inode(trans, root, dir);
	BUG_ON(ret);

528
	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
529
				 objectid, root->root_key.objectid,
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				 btrfs_ino(dir), index, name, namelen);
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	BUG_ON(ret);
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	ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
				  root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
				  objectid);
	if (ret)
		btrfs_abort_transaction(trans, root, ret);

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fail:
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	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
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	if (async_transid) {
		*async_transid = trans->transid;
		err = btrfs_commit_transaction_async(trans, root, 1);
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		if (err)
			err = btrfs_commit_transaction(trans, root);
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547 548 549
	} else {
		err = btrfs_commit_transaction(trans, root);
	}
C
Christoph Hellwig 已提交
550 551
	if (err && !ret)
		ret = err;
552 553 554

	if (!ret)
		d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
555 556
out:
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
C
Christoph Hellwig 已提交
557 558 559
	return ret;
}

560 561 562 563
static int create_snapshot(struct btrfs_root *root, struct inode *dir,
			   struct dentry *dentry, char *name, int namelen,
			   u64 *async_transid, bool readonly,
			   struct btrfs_qgroup_inherit *inherit)
C
Christoph Hellwig 已提交
564
{
565
	struct inode *inode;
C
Christoph Hellwig 已提交
566 567
	struct btrfs_pending_snapshot *pending_snapshot;
	struct btrfs_trans_handle *trans;
568
	int ret;
C
Christoph Hellwig 已提交
569 570 571 572

	if (!root->ref_cows)
		return -EINVAL;

573 574 575 576 577 578
	ret = btrfs_start_delalloc_inodes(root, 0);
	if (ret)
		return ret;

	btrfs_wait_ordered_extents(root, 0);

579
	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
580 581 582
	if (!pending_snapshot)
		return -ENOMEM;

583 584
	btrfs_init_block_rsv(&pending_snapshot->block_rsv,
			     BTRFS_BLOCK_RSV_TEMP);
585 586 587 588 589 590
	/*
	 * 1 - parent dir inode
	 * 2 - dir entries
	 * 1 - root item
	 * 2 - root ref/backref
	 * 1 - root of snapshot
591
	 * 1 - UUID item
592 593
	 */
	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
594
					&pending_snapshot->block_rsv, 8,
595 596
					&pending_snapshot->qgroup_reserved,
					false);
597 598 599
	if (ret)
		goto out;

600
	pending_snapshot->dentry = dentry;
C
Christoph Hellwig 已提交
601
	pending_snapshot->root = root;
L
Li Zefan 已提交
602
	pending_snapshot->readonly = readonly;
603
	pending_snapshot->dir = dir;
604
	pending_snapshot->inherit = inherit;
605

606
	trans = btrfs_start_transaction(root, 0);
607 608 609 610 611
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto fail;
	}

612
	spin_lock(&root->fs_info->trans_lock);
C
Christoph Hellwig 已提交
613 614
	list_add(&pending_snapshot->list,
		 &trans->transaction->pending_snapshots);
615
	spin_unlock(&root->fs_info->trans_lock);
S
Sage Weil 已提交
616 617 618 619
	if (async_transid) {
		*async_transid = trans->transid;
		ret = btrfs_commit_transaction_async(trans,
				     root->fs_info->extent_root, 1);
620 621
		if (ret)
			ret = btrfs_commit_transaction(trans, root);
S
Sage Weil 已提交
622 623 624 625
	} else {
		ret = btrfs_commit_transaction(trans,
					       root->fs_info->extent_root);
	}
626
	if (ret)
627
		goto fail;
628 629 630 631 632

	ret = pending_snapshot->error;
	if (ret)
		goto fail;

633 634 635
	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
	if (ret)
		goto fail;
C
Christoph Hellwig 已提交
636

637
	inode = btrfs_lookup_dentry(dentry->d_parent->d_inode, dentry);
638 639 640 641 642 643 644 645
	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto fail;
	}
	BUG_ON(!inode);
	d_instantiate(dentry, inode);
	ret = 0;
fail:
646 647 648 649
	btrfs_subvolume_release_metadata(BTRFS_I(dir)->root,
					 &pending_snapshot->block_rsv,
					 pending_snapshot->qgroup_reserved);
out:
650
	kfree(pending_snapshot);
C
Christoph Hellwig 已提交
651 652 653
	return ret;
}

654 655 656 657 658 659
/*  copy of check_sticky in fs/namei.c()
* It's inline, so penalty for filesystems that don't use sticky bit is
* minimal.
*/
static inline int btrfs_check_sticky(struct inode *dir, struct inode *inode)
{
660
	kuid_t fsuid = current_fsuid();
661 662 663

	if (!(dir->i_mode & S_ISVTX))
		return 0;
664
	if (uid_eq(inode->i_uid, fsuid))
665
		return 0;
666
	if (uid_eq(dir->i_uid, fsuid))
667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698
		return 0;
	return !capable(CAP_FOWNER);
}

/*  copy of may_delete in fs/namei.c()
 *	Check whether we can remove a link victim from directory dir, check
 *  whether the type of victim is right.
 *  1. We can't do it if dir is read-only (done in permission())
 *  2. We should have write and exec permissions on dir
 *  3. We can't remove anything from append-only dir
 *  4. We can't do anything with immutable dir (done in permission())
 *  5. If the sticky bit on dir is set we should either
 *	a. be owner of dir, or
 *	b. be owner of victim, or
 *	c. have CAP_FOWNER capability
 *  6. If the victim is append-only or immutable we can't do antyhing with
 *     links pointing to it.
 *  7. If we were asked to remove a directory and victim isn't one - ENOTDIR.
 *  8. If we were asked to remove a non-directory and victim isn't one - EISDIR.
 *  9. We can't remove a root or mountpoint.
 * 10. We don't allow removal of NFS sillyrenamed files; it's handled by
 *     nfs_async_unlink().
 */

static int btrfs_may_delete(struct inode *dir,struct dentry *victim,int isdir)
{
	int error;

	if (!victim->d_inode)
		return -ENOENT;

	BUG_ON(victim->d_parent->d_inode != dir);
699
	audit_inode_child(dir, victim, AUDIT_TYPE_CHILD_DELETE);
700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723

	error = inode_permission(dir, MAY_WRITE | MAY_EXEC);
	if (error)
		return error;
	if (IS_APPEND(dir))
		return -EPERM;
	if (btrfs_check_sticky(dir, victim->d_inode)||
		IS_APPEND(victim->d_inode)||
	    IS_IMMUTABLE(victim->d_inode) || IS_SWAPFILE(victim->d_inode))
		return -EPERM;
	if (isdir) {
		if (!S_ISDIR(victim->d_inode->i_mode))
			return -ENOTDIR;
		if (IS_ROOT(victim))
			return -EBUSY;
	} else if (S_ISDIR(victim->d_inode->i_mode))
		return -EISDIR;
	if (IS_DEADDIR(dir))
		return -ENOENT;
	if (victim->d_flags & DCACHE_NFSFS_RENAMED)
		return -EBUSY;
	return 0;
}

724 725 726 727 728 729 730 731 732 733 734 735 736 737 738
/* copy of may_create in fs/namei.c() */
static inline int btrfs_may_create(struct inode *dir, struct dentry *child)
{
	if (child->d_inode)
		return -EEXIST;
	if (IS_DEADDIR(dir))
		return -ENOENT;
	return inode_permission(dir, MAY_WRITE | MAY_EXEC);
}

/*
 * Create a new subvolume below @parent.  This is largely modeled after
 * sys_mkdirat and vfs_mkdir, but we only do a single component lookup
 * inside this filesystem so it's quite a bit simpler.
 */
739 740
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
S
Sage Weil 已提交
741
				   struct btrfs_root *snap_src,
A
Arne Jansen 已提交
742
				   u64 *async_transid, bool readonly,
743
				   struct btrfs_qgroup_inherit *inherit)
744
{
745
	struct inode *dir  = parent->dentry->d_inode;
746 747 748
	struct dentry *dentry;
	int error;

749 750 751
	error = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
	if (error == -EINTR)
		return error;
752 753 754 755 756 757 758 759 760 761

	dentry = lookup_one_len(name, parent->dentry, namelen);
	error = PTR_ERR(dentry);
	if (IS_ERR(dentry))
		goto out_unlock;

	error = -EEXIST;
	if (dentry->d_inode)
		goto out_dput;

762
	error = btrfs_may_create(dir, dentry);
763
	if (error)
764
		goto out_dput;
765

C
Chris Mason 已提交
766 767 768 769 770 771 772 773 774 775
	/*
	 * even if this name doesn't exist, we may get hash collisions.
	 * check for them now when we can safely fail
	 */
	error = btrfs_check_dir_item_collision(BTRFS_I(dir)->root,
					       dir->i_ino, name,
					       namelen);
	if (error)
		goto out_dput;

776 777 778 779 780
	down_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);

	if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
		goto out_up_read;

781
	if (snap_src) {
782
		error = create_snapshot(snap_src, dir, dentry, name, namelen,
A
Arne Jansen 已提交
783
					async_transid, readonly, inherit);
784
	} else {
785 786
		error = create_subvol(dir, dentry, name, namelen,
				      async_transid, inherit);
787
	}
788 789 790 791
	if (!error)
		fsnotify_mkdir(dir, dentry);
out_up_read:
	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
792 793 794
out_dput:
	dput(dentry);
out_unlock:
795
	mutex_unlock(&dir->i_mutex);
796 797 798
	return error;
}

C
Chris Mason 已提交
799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849
/*
 * When we're defragging a range, we don't want to kick it off again
 * if it is really just waiting for delalloc to send it down.
 * If we find a nice big extent or delalloc range for the bytes in the
 * file you want to defrag, we return 0 to let you know to skip this
 * part of the file
 */
static int check_defrag_in_cache(struct inode *inode, u64 offset, int thresh)
{
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
	struct extent_map *em = NULL;
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
	u64 end;

	read_lock(&em_tree->lock);
	em = lookup_extent_mapping(em_tree, offset, PAGE_CACHE_SIZE);
	read_unlock(&em_tree->lock);

	if (em) {
		end = extent_map_end(em);
		free_extent_map(em);
		if (end - offset > thresh)
			return 0;
	}
	/* if we already have a nice delalloc here, just stop */
	thresh /= 2;
	end = count_range_bits(io_tree, &offset, offset + thresh,
			       thresh, EXTENT_DELALLOC, 1);
	if (end >= thresh)
		return 0;
	return 1;
}

/*
 * helper function to walk through a file and find extents
 * newer than a specific transid, and smaller than thresh.
 *
 * This is used by the defragging code to find new and small
 * extents
 */
static int find_new_extents(struct btrfs_root *root,
			    struct inode *inode, u64 newer_than,
			    u64 *off, int thresh)
{
	struct btrfs_path *path;
	struct btrfs_key min_key;
	struct btrfs_key max_key;
	struct extent_buffer *leaf;
	struct btrfs_file_extent_item *extent;
	int type;
	int ret;
850
	u64 ino = btrfs_ino(inode);
C
Chris Mason 已提交
851 852 853 854 855

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

856
	min_key.objectid = ino;
C
Chris Mason 已提交
857 858 859
	min_key.type = BTRFS_EXTENT_DATA_KEY;
	min_key.offset = *off;

860
	max_key.objectid = ino;
C
Chris Mason 已提交
861 862 863 864 865 866 867
	max_key.type = (u8)-1;
	max_key.offset = (u64)-1;

	path->keep_locks = 1;

	while(1) {
		ret = btrfs_search_forward(root, &min_key, &max_key,
868
					   path, newer_than);
C
Chris Mason 已提交
869 870
		if (ret != 0)
			goto none;
871
		if (min_key.objectid != ino)
C
Chris Mason 已提交
872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899
			goto none;
		if (min_key.type != BTRFS_EXTENT_DATA_KEY)
			goto none;

		leaf = path->nodes[0];
		extent = btrfs_item_ptr(leaf, path->slots[0],
					struct btrfs_file_extent_item);

		type = btrfs_file_extent_type(leaf, extent);
		if (type == BTRFS_FILE_EXTENT_REG &&
		    btrfs_file_extent_num_bytes(leaf, extent) < thresh &&
		    check_defrag_in_cache(inode, min_key.offset, thresh)) {
			*off = min_key.offset;
			btrfs_free_path(path);
			return 0;
		}

		if (min_key.offset == (u64)-1)
			goto none;

		min_key.offset++;
		btrfs_release_path(path);
	}
none:
	btrfs_free_path(path);
	return -ENOENT;
}

L
Li Zefan 已提交
900
static struct extent_map *defrag_lookup_extent(struct inode *inode, u64 start)
901 902
{
	struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
L
Li Zefan 已提交
903 904 905
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
	struct extent_map *em;
	u64 len = PAGE_CACHE_SIZE;
906

L
Li Zefan 已提交
907 908 909 910
	/*
	 * hopefully we have this extent in the tree already, try without
	 * the full extent lock
	 */
911
	read_lock(&em_tree->lock);
L
Li Zefan 已提交
912
	em = lookup_extent_mapping(em_tree, start, len);
913 914
	read_unlock(&em_tree->lock);

L
Li Zefan 已提交
915 916 917 918 919 920 921 922 923 924 925 926
	if (!em) {
		/* get the big lock and read metadata off disk */
		lock_extent(io_tree, start, start + len - 1);
		em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
		unlock_extent(io_tree, start, start + len - 1);

		if (IS_ERR(em))
			return NULL;
	}

	return em;
}
927

L
Li Zefan 已提交
928 929 930 931 932 933 934 935 936 937 938 939 940 941
static bool defrag_check_next_extent(struct inode *inode, struct extent_map *em)
{
	struct extent_map *next;
	bool ret = true;

	/* this is the last extent */
	if (em->start + em->len >= i_size_read(inode))
		return false;

	next = defrag_lookup_extent(inode, em->start + em->len);
	if (!next || next->block_start >= EXTENT_MAP_LAST_BYTE)
		ret = false;

	free_extent_map(next);
942 943 944
	return ret;
}

L
Li Zefan 已提交
945
static int should_defrag_range(struct inode *inode, u64 start, int thresh,
946 947
			       u64 *last_len, u64 *skip, u64 *defrag_end,
			       int compress)
948
{
L
Li Zefan 已提交
949
	struct extent_map *em;
950
	int ret = 1;
L
Li Zefan 已提交
951
	bool next_mergeable = true;
952 953

	/*
954
	 * make sure that once we start defragging an extent, we keep on
955 956 957 958 959 960 961
	 * defragging it
	 */
	if (start < *defrag_end)
		return 1;

	*skip = 0;

L
Li Zefan 已提交
962 963 964
	em = defrag_lookup_extent(inode, start);
	if (!em)
		return 0;
965 966

	/* this will cover holes, and inline extents */
967
	if (em->block_start >= EXTENT_MAP_LAST_BYTE) {
968
		ret = 0;
969 970 971
		goto out;
	}

L
Li Zefan 已提交
972
	next_mergeable = defrag_check_next_extent(inode, em);
973 974

	/*
L
Li Zefan 已提交
975 976
	 * we hit a real extent, if it is big or the next extent is not a
	 * real extent, don't bother defragging it
977
	 */
978
	if (!compress && (*last_len == 0 || *last_len >= thresh) &&
L
Li Zefan 已提交
979
	    (em->len >= thresh || !next_mergeable))
980
		ret = 0;
981
out:
982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001
	/*
	 * last_len ends up being a counter of how many bytes we've defragged.
	 * every time we choose not to defrag an extent, we reset *last_len
	 * so that the next tiny extent will force a defrag.
	 *
	 * The end result of this is that tiny extents before a single big
	 * extent will force at least part of that big extent to be defragged.
	 */
	if (ret) {
		*defrag_end = extent_map_end(em);
	} else {
		*last_len = 0;
		*skip = extent_map_end(em);
		*defrag_end = 0;
	}

	free_extent_map(em);
	return ret;
}

C
Chris Mason 已提交
1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017
/*
 * it doesn't do much good to defrag one or two pages
 * at a time.  This pulls in a nice chunk of pages
 * to COW and defrag.
 *
 * It also makes sure the delalloc code has enough
 * dirty data to avoid making new small extents as part
 * of the defrag
 *
 * It's a good idea to start RA on this range
 * before calling this.
 */
static int cluster_pages_for_defrag(struct inode *inode,
				    struct page **pages,
				    unsigned long start_index,
				    int num_pages)
C
Christoph Hellwig 已提交
1018
{
C
Chris Mason 已提交
1019 1020 1021 1022
	unsigned long file_end;
	u64 isize = i_size_read(inode);
	u64 page_start;
	u64 page_end;
1023
	u64 page_cnt;
C
Chris Mason 已提交
1024 1025 1026
	int ret;
	int i;
	int i_done;
1027
	struct btrfs_ordered_extent *ordered;
C
Chris Mason 已提交
1028
	struct extent_state *cached_state = NULL;
1029
	struct extent_io_tree *tree;
1030
	gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
C
Chris Mason 已提交
1031 1032

	file_end = (isize - 1) >> PAGE_CACHE_SHIFT;
1033 1034 1035 1036
	if (!isize || start_index > file_end)
		return 0;

	page_cnt = min_t(u64, (u64)num_pages, (u64)file_end - start_index + 1);
C
Chris Mason 已提交
1037 1038

	ret = btrfs_delalloc_reserve_space(inode,
1039
					   page_cnt << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1040 1041 1042
	if (ret)
		return ret;
	i_done = 0;
1043
	tree = &BTRFS_I(inode)->io_tree;
C
Chris Mason 已提交
1044 1045

	/* step one, lock all the pages */
1046
	for (i = 0; i < page_cnt; i++) {
C
Chris Mason 已提交
1047
		struct page *page;
1048
again:
1049
		page = find_or_create_page(inode->i_mapping,
1050
					   start_index + i, mask);
C
Chris Mason 已提交
1051 1052 1053
		if (!page)
			break;

1054 1055 1056
		page_start = page_offset(page);
		page_end = page_start + PAGE_CACHE_SIZE - 1;
		while (1) {
1057
			lock_extent(tree, page_start, page_end);
1058 1059
			ordered = btrfs_lookup_ordered_extent(inode,
							      page_start);
1060
			unlock_extent(tree, page_start, page_end);
1061 1062 1063 1064 1065 1066 1067
			if (!ordered)
				break;

			unlock_page(page);
			btrfs_start_ordered_extent(inode, ordered, 1);
			btrfs_put_ordered_extent(ordered);
			lock_page(page);
1068 1069 1070 1071 1072 1073 1074 1075 1076
			/*
			 * we unlocked the page above, so we need check if
			 * it was released or not.
			 */
			if (page->mapping != inode->i_mapping) {
				unlock_page(page);
				page_cache_release(page);
				goto again;
			}
1077 1078
		}

C
Chris Mason 已提交
1079 1080 1081 1082 1083 1084 1085 1086 1087 1088
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
				page_cache_release(page);
				ret = -EIO;
				break;
			}
		}
1089 1090 1091 1092 1093 1094 1095

		if (page->mapping != inode->i_mapping) {
			unlock_page(page);
			page_cache_release(page);
			goto again;
		}

C
Chris Mason 已提交
1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115
		pages[i] = page;
		i_done++;
	}
	if (!i_done || ret)
		goto out;

	if (!(inode->i_sb->s_flags & MS_ACTIVE))
		goto out;

	/*
	 * so now we have a nice long stream of locked
	 * and up to date pages, lets wait on them
	 */
	for (i = 0; i < i_done; i++)
		wait_on_page_writeback(pages[i]);

	page_start = page_offset(pages[0]);
	page_end = page_offset(pages[i_done - 1]) + PAGE_CACHE_SIZE;

	lock_extent_bits(&BTRFS_I(inode)->io_tree,
1116
			 page_start, page_end - 1, 0, &cached_state);
C
Chris Mason 已提交
1117 1118
	clear_extent_bit(&BTRFS_I(inode)->io_tree, page_start,
			  page_end - 1, EXTENT_DIRTY | EXTENT_DELALLOC |
1119 1120
			  EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1121

1122
	if (i_done != page_cnt) {
1123 1124 1125
		spin_lock(&BTRFS_I(inode)->lock);
		BTRFS_I(inode)->outstanding_extents++;
		spin_unlock(&BTRFS_I(inode)->lock);
C
Chris Mason 已提交
1126
		btrfs_delalloc_release_space(inode,
1127
				     (page_cnt - i_done) << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1128 1129 1130
	}


1131 1132
	set_extent_defrag(&BTRFS_I(inode)->io_tree, page_start, page_end - 1,
			  &cached_state, GFP_NOFS);
C
Chris Mason 已提交
1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151

	unlock_extent_cached(&BTRFS_I(inode)->io_tree,
			     page_start, page_end - 1, &cached_state,
			     GFP_NOFS);

	for (i = 0; i < i_done; i++) {
		clear_page_dirty_for_io(pages[i]);
		ClearPageChecked(pages[i]);
		set_page_extent_mapped(pages[i]);
		set_page_dirty(pages[i]);
		unlock_page(pages[i]);
		page_cache_release(pages[i]);
	}
	return i_done;
out:
	for (i = 0; i < i_done; i++) {
		unlock_page(pages[i]);
		page_cache_release(pages[i]);
	}
1152
	btrfs_delalloc_release_space(inode, page_cnt << PAGE_CACHE_SHIFT);
C
Chris Mason 已提交
1153 1154 1155 1156 1157 1158 1159 1160 1161 1162
	return ret;

}

int btrfs_defrag_file(struct inode *inode, struct file *file,
		      struct btrfs_ioctl_defrag_range_args *range,
		      u64 newer_than, unsigned long max_to_defrag)
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct file_ra_state *ra = NULL;
C
Christoph Hellwig 已提交
1163
	unsigned long last_index;
1164
	u64 isize = i_size_read(inode);
1165 1166 1167
	u64 last_len = 0;
	u64 skip = 0;
	u64 defrag_end = 0;
C
Chris Mason 已提交
1168
	u64 newer_off = range->start;
C
Christoph Hellwig 已提交
1169
	unsigned long i;
1170
	unsigned long ra_index = 0;
C
Christoph Hellwig 已提交
1171
	int ret;
C
Chris Mason 已提交
1172
	int defrag_count = 0;
1173
	int compress_type = BTRFS_COMPRESS_ZLIB;
C
Chris Mason 已提交
1174
	int extent_thresh = range->extent_thresh;
1175 1176
	int max_cluster = (256 * 1024) >> PAGE_CACHE_SHIFT;
	int cluster = max_cluster;
C
Chris Mason 已提交
1177 1178 1179
	u64 new_align = ~((u64)128 * 1024 - 1);
	struct page **pages = NULL;

1180 1181 1182 1183 1184
	if (isize == 0)
		return 0;

	if (range->start >= isize)
		return -EINVAL;
1185 1186 1187 1188 1189 1190 1191

	if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
		if (range->compress_type > BTRFS_COMPRESS_TYPES)
			return -EINVAL;
		if (range->compress_type)
			compress_type = range->compress_type;
	}
C
Christoph Hellwig 已提交
1192

1193 1194
	if (extent_thresh == 0)
		extent_thresh = 256 * 1024;
1195

C
Chris Mason 已提交
1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208
	/*
	 * if we were not given a file, allocate a readahead
	 * context
	 */
	if (!file) {
		ra = kzalloc(sizeof(*ra), GFP_NOFS);
		if (!ra)
			return -ENOMEM;
		file_ra_state_init(ra, inode->i_mapping);
	} else {
		ra = &file->f_ra;
	}

1209
	pages = kmalloc(sizeof(struct page *) * max_cluster,
C
Chris Mason 已提交
1210 1211 1212 1213 1214 1215 1216
			GFP_NOFS);
	if (!pages) {
		ret = -ENOMEM;
		goto out_ra;
	}

	/* find the last page to defrag */
C
Chris Mason 已提交
1217
	if (range->start + range->len > range->start) {
1218
		last_index = min_t(u64, isize - 1,
C
Chris Mason 已提交
1219 1220
			 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
	} else {
1221
		last_index = (isize - 1) >> PAGE_CACHE_SHIFT;
C
Chris Mason 已提交
1222 1223
	}

C
Chris Mason 已提交
1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239
	if (newer_than) {
		ret = find_new_extents(root, inode, newer_than,
				       &newer_off, 64 * 1024);
		if (!ret) {
			range->start = newer_off;
			/*
			 * we always align our defrag to help keep
			 * the extents in the file evenly spaced
			 */
			i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
		} else
			goto out_ra;
	} else {
		i = range->start >> PAGE_CACHE_SHIFT;
	}
	if (!max_to_defrag)
L
Liu Bo 已提交
1240
		max_to_defrag = last_index + 1;
C
Chris Mason 已提交
1241

L
Li Zefan 已提交
1242 1243 1244 1245 1246 1247 1248
	/*
	 * make writeback starts from i, so the defrag range can be
	 * written sequentially.
	 */
	if (i < inode->i_mapping->writeback_index)
		inode->i_mapping->writeback_index = i;

1249 1250 1251
	while (i <= last_index && defrag_count < max_to_defrag &&
	       (i < (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >>
		PAGE_CACHE_SHIFT)) {
C
Chris Mason 已提交
1252 1253 1254 1255 1256 1257 1258
		/*
		 * make sure we stop running if someone unmounts
		 * the FS
		 */
		if (!(inode->i_sb->s_flags & MS_ACTIVE))
			break;

1259 1260 1261 1262 1263 1264
		if (btrfs_defrag_cancelled(root->fs_info)) {
			printk(KERN_DEBUG "btrfs: defrag_file cancelled\n");
			ret = -EAGAIN;
			break;
		}

1265
		if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
L
Li Zefan 已提交
1266
					 extent_thresh, &last_len, &skip,
1267 1268
					 &defrag_end, range->flags &
					 BTRFS_DEFRAG_RANGE_COMPRESS)) {
1269 1270 1271 1272 1273 1274 1275 1276 1277
			unsigned long next;
			/*
			 * the should_defrag function tells us how much to skip
			 * bump our counter by the suggested amount
			 */
			next = (skip + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
			i = max(i + 1, next);
			continue;
		}
1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292

		if (!newer_than) {
			cluster = (PAGE_CACHE_ALIGN(defrag_end) >>
				   PAGE_CACHE_SHIFT) - i;
			cluster = min(cluster, max_cluster);
		} else {
			cluster = max_cluster;
		}

		if (i + cluster > ra_index) {
			ra_index = max(i, ra_index);
			btrfs_force_ra(inode->i_mapping, ra, file, ra_index,
				       cluster);
			ra_index += max_cluster;
		}
1293

1294
		mutex_lock(&inode->i_mutex);
1295 1296
		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
			BTRFS_I(inode)->force_compress = compress_type;
1297
		ret = cluster_pages_for_defrag(inode, pages, i, cluster);
1298 1299
		if (ret < 0) {
			mutex_unlock(&inode->i_mutex);
C
Chris Mason 已提交
1300
			goto out_ra;
1301
		}
C
Chris Mason 已提交
1302 1303

		defrag_count += ret;
1304
		balance_dirty_pages_ratelimited(inode->i_mapping);
1305
		mutex_unlock(&inode->i_mutex);
C
Chris Mason 已提交
1306 1307 1308 1309 1310

		if (newer_than) {
			if (newer_off == (u64)-1)
				break;

1311 1312 1313
			if (ret > 0)
				i += ret;

C
Chris Mason 已提交
1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324
			newer_off = max(newer_off + 1,
					(u64)i << PAGE_CACHE_SHIFT);

			ret = find_new_extents(root, inode,
					       newer_than, &newer_off,
					       64 * 1024);
			if (!ret) {
				range->start = newer_off;
				i = (newer_off & new_align) >> PAGE_CACHE_SHIFT;
			} else {
				break;
C
Christoph Hellwig 已提交
1325
			}
C
Chris Mason 已提交
1326
		} else {
1327
			if (ret > 0) {
L
Li Zefan 已提交
1328
				i += ret;
1329 1330
				last_len += ret << PAGE_CACHE_SHIFT;
			} else {
L
Li Zefan 已提交
1331
				i++;
1332 1333
				last_len = 0;
			}
C
Christoph Hellwig 已提交
1334 1335 1336
		}
	}

C
Chris Mason 已提交
1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354
	if ((range->flags & BTRFS_DEFRAG_RANGE_START_IO))
		filemap_flush(inode->i_mapping);

	if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
		/* the filemap_flush will queue IO into the worker threads, but
		 * we have to make sure the IO is actually started and that
		 * ordered extents get created before we return
		 */
		atomic_inc(&root->fs_info->async_submit_draining);
		while (atomic_read(&root->fs_info->nr_async_submits) ||
		      atomic_read(&root->fs_info->async_delalloc_pages)) {
			wait_event(root->fs_info->async_submit_wait,
			   (atomic_read(&root->fs_info->nr_async_submits) == 0 &&
			    atomic_read(&root->fs_info->async_delalloc_pages) == 0));
		}
		atomic_dec(&root->fs_info->async_submit_draining);
	}

1355
	if (range->compress_type == BTRFS_COMPRESS_LZO) {
1356
		btrfs_set_fs_incompat(root->fs_info, COMPRESS_LZO);
1357 1358
	}

1359
	ret = defrag_count;
1360

C
Chris Mason 已提交
1361
out_ra:
1362 1363 1364 1365 1366
	if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS) {
		mutex_lock(&inode->i_mutex);
		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
		mutex_unlock(&inode->i_mutex);
	}
C
Chris Mason 已提交
1367 1368 1369
	if (!file)
		kfree(ra);
	kfree(pages);
1370
	return ret;
C
Christoph Hellwig 已提交
1371 1372
}

1373
static noinline int btrfs_ioctl_resize(struct file *file,
1374
					void __user *arg)
C
Christoph Hellwig 已提交
1375 1376 1377 1378
{
	u64 new_size;
	u64 old_size;
	u64 devid = 1;
A
Al Viro 已提交
1379
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
1380 1381 1382 1383 1384 1385 1386 1387
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;
	struct btrfs_device *device = NULL;
	char *sizestr;
	char *devstr = NULL;
	int ret = 0;
	int mod = 0;

1388 1389 1390
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

1391 1392 1393 1394
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

1395 1396 1397
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
		pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
1398
		mnt_drop_write_file(file);
1399
		return -EINVAL;
1400 1401
	}

1402
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
1403
	vol_args = memdup_user(arg, sizeof(*vol_args));
1404 1405 1406 1407
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
1408 1409

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1410 1411 1412 1413 1414 1415 1416 1417 1418

	sizestr = vol_args->name;
	devstr = strchr(sizestr, ':');
	if (devstr) {
		char *end;
		sizestr = devstr + 1;
		*devstr = '\0';
		devstr = vol_args->name;
		devid = simple_strtoull(devstr, &end, 10);
1419 1420 1421 1422
		if (!devid) {
			ret = -EINVAL;
			goto out_free;
		}
1423
		printk(KERN_INFO "btrfs: resizing devid %llu\n", devid);
C
Christoph Hellwig 已提交
1424
	}
M
Miao Xie 已提交
1425

1426
	device = btrfs_find_device(root->fs_info, devid, NULL, NULL);
C
Christoph Hellwig 已提交
1427
	if (!device) {
1428
		printk(KERN_INFO "btrfs: resizer unable to find device %llu\n",
1429
		       devid);
1430
		ret = -ENODEV;
1431
		goto out_free;
C
Christoph Hellwig 已提交
1432
	}
M
Miao Xie 已提交
1433 1434

	if (!device->writeable) {
L
Liu Bo 已提交
1435
		printk(KERN_INFO "btrfs: resizer unable to apply on "
M
Miao Xie 已提交
1436
		       "readonly device %llu\n",
1437
		       devid);
1438
		ret = -EPERM;
L
Liu Bo 已提交
1439 1440 1441
		goto out_free;
	}

C
Christoph Hellwig 已提交
1442 1443 1444 1445 1446 1447 1448 1449 1450 1451
	if (!strcmp(sizestr, "max"))
		new_size = device->bdev->bd_inode->i_size;
	else {
		if (sizestr[0] == '-') {
			mod = -1;
			sizestr++;
		} else if (sizestr[0] == '+') {
			mod = 1;
			sizestr++;
		}
A
Akinobu Mita 已提交
1452
		new_size = memparse(sizestr, NULL);
C
Christoph Hellwig 已提交
1453 1454
		if (new_size == 0) {
			ret = -EINVAL;
1455
			goto out_free;
C
Christoph Hellwig 已提交
1456 1457 1458
		}
	}

1459
	if (device->is_tgtdev_for_dev_replace) {
1460
		ret = -EPERM;
1461 1462 1463
		goto out_free;
	}

C
Christoph Hellwig 已提交
1464 1465 1466 1467 1468
	old_size = device->total_bytes;

	if (mod < 0) {
		if (new_size > old_size) {
			ret = -EINVAL;
1469
			goto out_free;
C
Christoph Hellwig 已提交
1470 1471 1472 1473 1474 1475 1476 1477
		}
		new_size = old_size - new_size;
	} else if (mod > 0) {
		new_size = old_size + new_size;
	}

	if (new_size < 256 * 1024 * 1024) {
		ret = -EINVAL;
1478
		goto out_free;
C
Christoph Hellwig 已提交
1479 1480 1481
	}
	if (new_size > device->bdev->bd_inode->i_size) {
		ret = -EFBIG;
1482
		goto out_free;
C
Christoph Hellwig 已提交
1483 1484 1485 1486 1487
	}

	do_div(new_size, root->sectorsize);
	new_size *= root->sectorsize;

1488
	printk_in_rcu(KERN_INFO "btrfs: new size for %s is %llu\n",
1489
		      rcu_str_deref(device->name), new_size);
C
Christoph Hellwig 已提交
1490 1491

	if (new_size > old_size) {
1492
		trans = btrfs_start_transaction(root, 0);
1493 1494
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
1495
			goto out_free;
1496
		}
C
Christoph Hellwig 已提交
1497 1498
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
1499
	} else if (new_size < old_size) {
C
Christoph Hellwig 已提交
1500
		ret = btrfs_shrink_device(device, new_size);
1501
	} /* equal, nothing need to do */
C
Christoph Hellwig 已提交
1502

1503
out_free:
C
Christoph Hellwig 已提交
1504
	kfree(vol_args);
1505 1506
out:
	mutex_unlock(&root->fs_info->volume_mutex);
1507
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
1508
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1509 1510 1511
	return ret;
}

S
Sage Weil 已提交
1512
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
A
Arne Jansen 已提交
1513 1514
				char *name, unsigned long fd, int subvol,
				u64 *transid, bool readonly,
1515
				struct btrfs_qgroup_inherit *inherit)
C
Christoph Hellwig 已提交
1516 1517
{
	int namelen;
1518
	int ret = 0;
C
Christoph Hellwig 已提交
1519

1520 1521 1522 1523
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;

S
Sage Weil 已提交
1524 1525
	namelen = strlen(name);
	if (strchr(name, '/')) {
C
Christoph Hellwig 已提交
1526
		ret = -EINVAL;
1527
		goto out_drop_write;
C
Christoph Hellwig 已提交
1528 1529
	}

1530 1531 1532
	if (name[0] == '.' &&
	   (namelen == 1 || (name[1] == '.' && namelen == 2))) {
		ret = -EEXIST;
1533
		goto out_drop_write;
1534 1535
	}

1536
	if (subvol) {
S
Sage Weil 已提交
1537
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
A
Arne Jansen 已提交
1538
				     NULL, transid, readonly, inherit);
1539
	} else {
1540
		struct fd src = fdget(fd);
1541
		struct inode *src_inode;
1542
		if (!src.file) {
1543
			ret = -EINVAL;
1544
			goto out_drop_write;
1545 1546
		}

A
Al Viro 已提交
1547 1548
		src_inode = file_inode(src.file);
		if (src_inode->i_sb != file_inode(file)->i_sb) {
C
Chris Mason 已提交
1549 1550
			printk(KERN_INFO "btrfs: Snapshot src from "
			       "another FS\n");
1551
			ret = -EINVAL;
1552 1553 1554 1555
		} else {
			ret = btrfs_mksubvol(&file->f_path, name, namelen,
					     BTRFS_I(src_inode)->root,
					     transid, readonly, inherit);
1556
		}
1557
		fdput(src);
1558
	}
1559 1560
out_drop_write:
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
1561
out:
S
Sage Weil 已提交
1562 1563 1564 1565
	return ret;
}

static noinline int btrfs_ioctl_snap_create(struct file *file,
1566
					    void __user *arg, int subvol)
S
Sage Weil 已提交
1567
{
1568
	struct btrfs_ioctl_vol_args *vol_args;
S
Sage Weil 已提交
1569 1570
	int ret;

1571 1572 1573 1574
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
S
Sage Weil 已提交
1575

1576
	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1577
					      vol_args->fd, subvol,
A
Arne Jansen 已提交
1578
					      NULL, false, NULL);
1579

1580 1581 1582
	kfree(vol_args);
	return ret;
}
1583

1584 1585 1586 1587 1588 1589 1590
static noinline int btrfs_ioctl_snap_create_v2(struct file *file,
					       void __user *arg, int subvol)
{
	struct btrfs_ioctl_vol_args_v2 *vol_args;
	int ret;
	u64 transid = 0;
	u64 *ptr = NULL;
L
Li Zefan 已提交
1591
	bool readonly = false;
A
Arne Jansen 已提交
1592
	struct btrfs_qgroup_inherit *inherit = NULL;
1593

1594 1595 1596 1597
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
	vol_args->name[BTRFS_SUBVOL_NAME_MAX] = '\0';
1598

L
Li Zefan 已提交
1599
	if (vol_args->flags &
A
Arne Jansen 已提交
1600 1601
	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY |
	      BTRFS_SUBVOL_QGROUP_INHERIT)) {
L
Li Zefan 已提交
1602
		ret = -EOPNOTSUPP;
1603
		goto out;
S
Sage Weil 已提交
1604
	}
1605 1606 1607

	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
		ptr = &transid;
L
Li Zefan 已提交
1608 1609
	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
		readonly = true;
A
Arne Jansen 已提交
1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620
	if (vol_args->flags & BTRFS_SUBVOL_QGROUP_INHERIT) {
		if (vol_args->size > PAGE_CACHE_SIZE) {
			ret = -EINVAL;
			goto out;
		}
		inherit = memdup_user(vol_args->qgroup_inherit, vol_args->size);
		if (IS_ERR(inherit)) {
			ret = PTR_ERR(inherit);
			goto out;
		}
	}
1621 1622

	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
A
Arne Jansen 已提交
1623
					      vol_args->fd, subvol, ptr,
1624
					      readonly, inherit);
1625 1626 1627 1628 1629 1630

	if (ret == 0 && ptr &&
	    copy_to_user(arg +
			 offsetof(struct btrfs_ioctl_vol_args_v2,
				  transid), ptr, sizeof(*ptr)))
		ret = -EFAULT;
1631
out:
C
Christoph Hellwig 已提交
1632
	kfree(vol_args);
A
Arne Jansen 已提交
1633
	kfree(inherit);
C
Christoph Hellwig 已提交
1634 1635 1636
	return ret;
}

1637 1638 1639
static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
						void __user *arg)
{
A
Al Viro 已提交
1640
	struct inode *inode = file_inode(file);
1641 1642 1643 1644
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret = 0;
	u64 flags = 0;

L
Li Zefan 已提交
1645
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID)
1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661
		return -EINVAL;

	down_read(&root->fs_info->subvol_sem);
	if (btrfs_root_readonly(root))
		flags |= BTRFS_SUBVOL_RDONLY;
	up_read(&root->fs_info->subvol_sem);

	if (copy_to_user(arg, &flags, sizeof(flags)))
		ret = -EFAULT;

	return ret;
}

static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
					      void __user *arg)
{
A
Al Viro 已提交
1662
	struct inode *inode = file_inode(file);
1663 1664 1665 1666 1667 1668
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
	u64 root_flags;
	u64 flags;
	int ret = 0;

1669 1670 1671
	ret = mnt_want_write_file(file);
	if (ret)
		goto out;
1672

1673 1674 1675 1676
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1677

1678 1679 1680 1681
	if (copy_from_user(&flags, arg, sizeof(flags))) {
		ret = -EFAULT;
		goto out_drop_write;
	}
1682

1683 1684 1685 1686
	if (flags & BTRFS_SUBVOL_CREATE_ASYNC) {
		ret = -EINVAL;
		goto out_drop_write;
	}
1687

1688 1689 1690 1691
	if (flags & ~BTRFS_SUBVOL_RDONLY) {
		ret = -EOPNOTSUPP;
		goto out_drop_write;
	}
1692

1693 1694 1695 1696
	if (!inode_owner_or_capable(inode)) {
		ret = -EACCES;
		goto out_drop_write;
	}
1697

1698 1699 1700 1701
	down_write(&root->fs_info->subvol_sem);

	/* nothing to do */
	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
1702
		goto out_drop_sem;
1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717

	root_flags = btrfs_root_flags(&root->root_item);
	if (flags & BTRFS_SUBVOL_RDONLY)
		btrfs_set_root_flags(&root->root_item,
				     root_flags | BTRFS_ROOT_SUBVOL_RDONLY);
	else
		btrfs_set_root_flags(&root->root_item,
				     root_flags & ~BTRFS_ROOT_SUBVOL_RDONLY);

	trans = btrfs_start_transaction(root, 1);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_reset;
	}

1718
	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1719 1720 1721 1722 1723 1724
				&root->root_key, &root->root_item);

	btrfs_commit_transaction(trans, root);
out_reset:
	if (ret)
		btrfs_set_root_flags(&root->root_item, root_flags);
1725
out_drop_sem:
1726
	up_write(&root->fs_info->subvol_sem);
1727 1728 1729
out_drop_write:
	mnt_drop_write_file(file);
out:
1730 1731 1732
	return ret;
}

1733 1734 1735 1736 1737 1738
/*
 * helper to check if the subvolume references other subvolumes
 */
static noinline int may_destroy_subvol(struct btrfs_root *root)
{
	struct btrfs_path *path;
1739
	struct btrfs_dir_item *di;
1740
	struct btrfs_key key;
1741
	u64 dir_id;
1742 1743 1744 1745 1746 1747
	int ret;

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760
	/* Make sure this root isn't set as the default subvol */
	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
	di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 0);
	if (di && !IS_ERR(di)) {
		btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
		if (key.objectid == root->root_key.objectid) {
			ret = -ENOTEMPTY;
			goto out;
		}
		btrfs_release_path(path);
	}

1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783
	key.objectid = root->root_key.objectid;
	key.type = BTRFS_ROOT_REF_KEY;
	key.offset = (u64)-1;

	ret = btrfs_search_slot(NULL, root->fs_info->tree_root,
				&key, path, 0, 0);
	if (ret < 0)
		goto out;
	BUG_ON(ret == 0);

	ret = 0;
	if (path->slots[0] > 0) {
		path->slots[0]--;
		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
		if (key.objectid == root->root_key.objectid &&
		    key.type == BTRFS_ROOT_REF_KEY)
			ret = -ENOTEMPTY;
	}
out:
	btrfs_free_path(path);
	return ret;
}

1784 1785 1786
static noinline int key_in_sk(struct btrfs_key *key,
			      struct btrfs_ioctl_search_key *sk)
{
1787 1788 1789 1790 1791 1792 1793 1794 1795
	struct btrfs_key test;
	int ret;

	test.objectid = sk->min_objectid;
	test.type = sk->min_type;
	test.offset = sk->min_offset;

	ret = btrfs_comp_cpu_keys(key, &test);
	if (ret < 0)
1796
		return 0;
1797 1798 1799 1800 1801 1802 1803

	test.objectid = sk->max_objectid;
	test.type = sk->max_type;
	test.offset = sk->max_offset;

	ret = btrfs_comp_cpu_keys(key, &test);
	if (ret > 0)
1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839
		return 0;
	return 1;
}

static noinline int copy_to_sk(struct btrfs_root *root,
			       struct btrfs_path *path,
			       struct btrfs_key *key,
			       struct btrfs_ioctl_search_key *sk,
			       char *buf,
			       unsigned long *sk_offset,
			       int *num_found)
{
	u64 found_transid;
	struct extent_buffer *leaf;
	struct btrfs_ioctl_search_header sh;
	unsigned long item_off;
	unsigned long item_len;
	int nritems;
	int i;
	int slot;
	int ret = 0;

	leaf = path->nodes[0];
	slot = path->slots[0];
	nritems = btrfs_header_nritems(leaf);

	if (btrfs_header_generation(leaf) > sk->max_transid) {
		i = nritems;
		goto advance_key;
	}
	found_transid = btrfs_header_generation(leaf);

	for (i = slot; i < nritems; i++) {
		item_off = btrfs_item_ptr_offset(leaf, i);
		item_len = btrfs_item_size_nr(leaf, i);

1840 1841 1842 1843 1844
		btrfs_item_key_to_cpu(leaf, key, i);
		if (!key_in_sk(key, sk))
			continue;

		if (sizeof(sh) + item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869
			item_len = 0;

		if (sizeof(sh) + item_len + *sk_offset >
		    BTRFS_SEARCH_ARGS_BUFSIZE) {
			ret = 1;
			goto overflow;
		}

		sh.objectid = key->objectid;
		sh.offset = key->offset;
		sh.type = key->type;
		sh.len = item_len;
		sh.transid = found_transid;

		/* copy search result header */
		memcpy(buf + *sk_offset, &sh, sizeof(sh));
		*sk_offset += sizeof(sh);

		if (item_len) {
			char *p = buf + *sk_offset;
			/* copy the item */
			read_extent_buffer(leaf, p,
					   item_off, item_len);
			*sk_offset += item_len;
		}
1870
		(*num_found)++;
1871 1872 1873 1874 1875

		if (*num_found >= sk->nr_items)
			break;
	}
advance_key:
1876 1877
	ret = 0;
	if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1878
		key->offset++;
1879 1880
	else if (key->type < (u8)-1 && key->type < sk->max_type) {
		key->offset = 0;
1881
		key->type++;
1882 1883 1884
	} else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
		key->offset = 0;
		key->type = 0;
1885
		key->objectid++;
1886 1887
	} else
		ret = 1;
1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935
overflow:
	return ret;
}

static noinline int search_ioctl(struct inode *inode,
				 struct btrfs_ioctl_search_args *args)
{
	struct btrfs_root *root;
	struct btrfs_key key;
	struct btrfs_key max_key;
	struct btrfs_path *path;
	struct btrfs_ioctl_search_key *sk = &args->key;
	struct btrfs_fs_info *info = BTRFS_I(inode)->root->fs_info;
	int ret;
	int num_found = 0;
	unsigned long sk_offset = 0;

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

	if (sk->tree_id == 0) {
		/* search the root of the inode that was passed */
		root = BTRFS_I(inode)->root;
	} else {
		key.objectid = sk->tree_id;
		key.type = BTRFS_ROOT_ITEM_KEY;
		key.offset = (u64)-1;
		root = btrfs_read_fs_root_no_name(info, &key);
		if (IS_ERR(root)) {
			printk(KERN_ERR "could not find root %llu\n",
			       sk->tree_id);
			btrfs_free_path(path);
			return -ENOENT;
		}
	}

	key.objectid = sk->min_objectid;
	key.type = sk->min_type;
	key.offset = sk->min_offset;

	max_key.objectid = sk->max_objectid;
	max_key.type = sk->max_type;
	max_key.offset = sk->max_offset;

	path->keep_locks = 1;

	while(1) {
1936
		ret = btrfs_search_forward(root, &key, &max_key, path,
1937 1938 1939 1940 1941 1942 1943 1944
					   sk->min_transid);
		if (ret != 0) {
			if (ret > 0)
				ret = 0;
			goto err;
		}
		ret = copy_to_sk(root, path, &key, sk, args->buf,
				 &sk_offset, &num_found);
1945
		btrfs_release_path(path);
1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966
		if (ret || num_found >= sk->nr_items)
			break;

	}
	ret = 0;
err:
	sk->nr_items = num_found;
	btrfs_free_path(path);
	return ret;
}

static noinline int btrfs_ioctl_tree_search(struct file *file,
					   void __user *argp)
{
	 struct btrfs_ioctl_search_args *args;
	 struct inode *inode;
	 int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

J
Julia Lawall 已提交
1967 1968 1969
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
1970

A
Al Viro 已提交
1971
	inode = file_inode(file);
1972 1973 1974 1975 1976 1977 1978
	ret = search_ioctl(inode, args);
	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
		ret = -EFAULT;
	kfree(args);
	return ret;
}

1979
/*
1980 1981 1982
 * Search INODE_REFs to identify path name of 'dirid' directory
 * in a 'tree_id' tree. and sets path name to 'name'.
 */
1983 1984 1985 1986 1987
static noinline int btrfs_search_path_in_tree(struct btrfs_fs_info *info,
				u64 tree_id, u64 dirid, char *name)
{
	struct btrfs_root *root;
	struct btrfs_key key;
1988
	char *ptr;
1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
	int ret = -1;
	int slot;
	int len;
	int total_len = 0;
	struct btrfs_inode_ref *iref;
	struct extent_buffer *l;
	struct btrfs_path *path;

	if (dirid == BTRFS_FIRST_FREE_OBJECTID) {
		name[0]='\0';
		return 0;
	}

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;

2006
	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
2007 2008 2009 2010 2011 2012 2013

	key.objectid = tree_id;
	key.type = BTRFS_ROOT_ITEM_KEY;
	key.offset = (u64)-1;
	root = btrfs_read_fs_root_no_name(info, &key);
	if (IS_ERR(root)) {
		printk(KERN_ERR "could not find root %llu\n", tree_id);
2014 2015
		ret = -ENOENT;
		goto out;
2016 2017 2018 2019
	}

	key.objectid = dirid;
	key.type = BTRFS_INODE_REF_KEY;
2020
	key.offset = (u64)-1;
2021 2022 2023 2024 2025

	while(1) {
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
		if (ret < 0)
			goto out;
2026 2027 2028 2029 2030 2031 2032 2033 2034 2035
		else if (ret > 0) {
			ret = btrfs_previous_item(root, path, dirid,
						  BTRFS_INODE_REF_KEY);
			if (ret < 0)
				goto out;
			else if (ret > 0) {
				ret = -ENOENT;
				goto out;
			}
		}
2036 2037 2038 2039 2040 2041 2042 2043 2044

		l = path->nodes[0];
		slot = path->slots[0];
		btrfs_item_key_to_cpu(l, &key, slot);

		iref = btrfs_item_ptr(l, slot, struct btrfs_inode_ref);
		len = btrfs_inode_ref_name_len(l, iref);
		ptr -= len + 1;
		total_len += len + 1;
2045 2046
		if (ptr < name) {
			ret = -ENAMETOOLONG;
2047
			goto out;
2048
		}
2049 2050 2051 2052 2053 2054 2055

		*(ptr + len) = '/';
		read_extent_buffer(l, ptr,(unsigned long)(iref + 1), len);

		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
			break;

2056
		btrfs_release_path(path);
2057
		key.objectid = key.offset;
2058
		key.offset = (u64)-1;
2059 2060
		dirid = key.objectid;
	}
2061
	memmove(name, ptr, total_len);
2062 2063 2064 2065
	name[total_len]='\0';
	ret = 0;
out:
	btrfs_free_path(path);
2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078
	return ret;
}

static noinline int btrfs_ioctl_ino_lookup(struct file *file,
					   void __user *argp)
{
	 struct btrfs_ioctl_ino_lookup_args *args;
	 struct inode *inode;
	 int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

J
Julia Lawall 已提交
2079 2080 2081
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
2082

A
Al Viro 已提交
2083
	inode = file_inode(file);
2084

2085 2086 2087
	if (args->treeid == 0)
		args->treeid = BTRFS_I(inode)->root->root_key.objectid;

2088 2089 2090 2091 2092 2093 2094 2095
	ret = btrfs_search_path_in_tree(BTRFS_I(inode)->root->fs_info,
					args->treeid, args->objectid,
					args->name);

	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
		ret = -EFAULT;

	kfree(args);
2096 2097 2098
	return ret;
}

2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109
static noinline int btrfs_ioctl_snap_destroy(struct file *file,
					     void __user *arg)
{
	struct dentry *parent = fdentry(file);
	struct dentry *dentry;
	struct inode *dir = parent->d_inode;
	struct inode *inode;
	struct btrfs_root *root = BTRFS_I(dir)->root;
	struct btrfs_root *dest = NULL;
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_trans_handle *trans;
2110 2111
	struct btrfs_block_rsv block_rsv;
	u64 qgroup_reserved;
2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127
	int namelen;
	int ret;
	int err = 0;

	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
	namelen = strlen(vol_args->name);
	if (strchr(vol_args->name, '/') ||
	    strncmp(vol_args->name, "..", namelen) == 0) {
		err = -EINVAL;
		goto out;
	}

2128
	err = mnt_want_write_file(file);
2129 2130 2131
	if (err)
		goto out;

2132 2133 2134
	err = mutex_lock_killable_nested(&dir->i_mutex, I_MUTEX_PARENT);
	if (err == -EINTR)
		goto out;
2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146
	dentry = lookup_one_len(vol_args->name, parent, namelen);
	if (IS_ERR(dentry)) {
		err = PTR_ERR(dentry);
		goto out_unlock_dir;
	}

	if (!dentry->d_inode) {
		err = -ENOENT;
		goto out_dput;
	}

	inode = dentry->d_inode;
2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181
	dest = BTRFS_I(inode)->root;
	if (!capable(CAP_SYS_ADMIN)){
		/*
		 * Regular user.  Only allow this with a special mount
		 * option, when the user has write+exec access to the
		 * subvol root, and when rmdir(2) would have been
		 * allowed.
		 *
		 * Note that this is _not_ check that the subvol is
		 * empty or doesn't contain data that we wouldn't
		 * otherwise be able to delete.
		 *
		 * Users who want to delete empty subvols should try
		 * rmdir(2).
		 */
		err = -EPERM;
		if (!btrfs_test_opt(root, USER_SUBVOL_RM_ALLOWED))
			goto out_dput;

		/*
		 * Do not allow deletion if the parent dir is the same
		 * as the dir to be deleted.  That means the ioctl
		 * must be called on the dentry referencing the root
		 * of the subvol, not a random directory contained
		 * within it.
		 */
		err = -EINVAL;
		if (root == dest)
			goto out_dput;

		err = inode_permission(inode, MAY_WRITE | MAY_EXEC);
		if (err)
			goto out_dput;
	}

2182 2183 2184 2185 2186
	/* check if subvolume may be deleted by a user */
	err = btrfs_may_delete(dir, dentry, 1);
	if (err)
		goto out_dput;

L
Li Zefan 已提交
2187
	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202
		err = -EINVAL;
		goto out_dput;
	}

	mutex_lock(&inode->i_mutex);
	err = d_invalidate(dentry);
	if (err)
		goto out_unlock;

	down_write(&root->fs_info->subvol_sem);

	err = may_destroy_subvol(dest);
	if (err)
		goto out_up_write;

2203 2204 2205 2206 2207 2208
	btrfs_init_block_rsv(&block_rsv, BTRFS_BLOCK_RSV_TEMP);
	/*
	 * One for dir inode, two for dir entries, two for root
	 * ref/backref.
	 */
	err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
2209
					       5, &qgroup_reserved, true);
2210 2211 2212
	if (err)
		goto out_up_write;

2213 2214 2215
	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		err = PTR_ERR(trans);
2216
		goto out_release;
2217
	}
2218 2219
	trans->block_rsv = &block_rsv;
	trans->bytes_reserved = block_rsv.size;
2220

2221 2222 2223 2224
	ret = btrfs_unlink_subvol(trans, root, dir,
				dest->root_key.objectid,
				dentry->d_name.name,
				dentry->d_name.len);
2225 2226 2227 2228 2229
	if (ret) {
		err = ret;
		btrfs_abort_transaction(trans, root, ret);
		goto out_end_trans;
	}
2230 2231 2232 2233 2234 2235 2236 2237

	btrfs_record_root_in_trans(trans, dest);

	memset(&dest->root_item.drop_progress, 0,
		sizeof(dest->root_item.drop_progress));
	dest->root_item.drop_level = 0;
	btrfs_set_root_refs(&dest->root_item, 0);

2238 2239 2240 2241
	if (!xchg(&dest->orphan_item_inserted, 1)) {
		ret = btrfs_insert_orphan_item(trans,
					root->fs_info->tree_root,
					dest->root_key.objectid);
2242 2243 2244 2245 2246
		if (ret) {
			btrfs_abort_transaction(trans, root, ret);
			err = ret;
			goto out_end_trans;
		}
2247
	}
2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268

	ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
				  dest->root_item.uuid, BTRFS_UUID_KEY_SUBVOL,
				  dest->root_key.objectid);
	if (ret && ret != -ENOENT) {
		btrfs_abort_transaction(trans, root, ret);
		err = ret;
		goto out_end_trans;
	}
	if (!btrfs_is_empty_uuid(dest->root_item.received_uuid)) {
		ret = btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
					  dest->root_item.received_uuid,
					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
					  dest->root_key.objectid);
		if (ret && ret != -ENOENT) {
			btrfs_abort_transaction(trans, root, ret);
			err = ret;
			goto out_end_trans;
		}
	}

2269
out_end_trans:
2270 2271
	trans->block_rsv = NULL;
	trans->bytes_reserved = 0;
S
Sage Weil 已提交
2272
	ret = btrfs_end_transaction(trans, root);
2273 2274
	if (ret && !err)
		err = ret;
2275
	inode->i_flags |= S_DEAD;
2276 2277
out_release:
	btrfs_subvolume_release_metadata(root, &block_rsv, qgroup_reserved);
2278 2279 2280 2281 2282
out_up_write:
	up_write(&root->fs_info->subvol_sem);
out_unlock:
	mutex_unlock(&inode->i_mutex);
	if (!err) {
2283
		shrink_dcache_sb(root->fs_info->sb);
2284 2285
		btrfs_invalidate_inodes(dest);
		d_delete(dentry);
2286 2287 2288 2289 2290 2291

		/* the last ref */
		if (dest->cache_inode) {
			iput(dest->cache_inode);
			dest->cache_inode = NULL;
		}
2292 2293 2294 2295 2296
	}
out_dput:
	dput(dentry);
out_unlock_dir:
	mutex_unlock(&dir->i_mutex);
A
Al Viro 已提交
2297
	mnt_drop_write_file(file);
2298 2299 2300 2301 2302
out:
	kfree(vol_args);
	return err;
}

C
Chris Mason 已提交
2303
static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
C
Christoph Hellwig 已提交
2304
{
A
Al Viro 已提交
2305
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
2306
	struct btrfs_root *root = BTRFS_I(inode)->root;
C
Chris Mason 已提交
2307
	struct btrfs_ioctl_defrag_range_args *range;
Y
Yan Zheng 已提交
2308 2309
	int ret;

2310 2311 2312
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
L
Li Zefan 已提交
2313

2314 2315 2316
	if (btrfs_root_readonly(root)) {
		ret = -EROFS;
		goto out;
2317
	}
C
Christoph Hellwig 已提交
2318 2319 2320

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
2321 2322 2323 2324
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
2325
		ret = btrfs_defrag_root(root);
2326 2327
		if (ret)
			goto out;
2328
		ret = btrfs_defrag_root(root->fs_info->extent_root);
C
Christoph Hellwig 已提交
2329 2330
		break;
	case S_IFREG:
2331 2332 2333 2334
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Chris Mason 已提交
2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346

		range = kzalloc(sizeof(*range), GFP_KERNEL);
		if (!range) {
			ret = -ENOMEM;
			goto out;
		}

		if (argp) {
			if (copy_from_user(range, argp,
					   sizeof(*range))) {
				ret = -EFAULT;
				kfree(range);
2347
				goto out;
C
Chris Mason 已提交
2348 2349 2350 2351 2352 2353 2354 2355 2356 2357
			}
			/* compression requires us to start the IO */
			if ((range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)) {
				range->flags |= BTRFS_DEFRAG_RANGE_START_IO;
				range->extent_thresh = (u32)-1;
			}
		} else {
			/* the rest are all set to zero by kzalloc */
			range->len = (u64)-1;
		}
A
Al Viro 已提交
2358
		ret = btrfs_defrag_file(file_inode(file), file,
C
Chris Mason 已提交
2359 2360 2361
					range, 0, 0);
		if (ret > 0)
			ret = 0;
C
Chris Mason 已提交
2362
		kfree(range);
C
Christoph Hellwig 已提交
2363
		break;
2364 2365
	default:
		ret = -EINVAL;
C
Christoph Hellwig 已提交
2366
	}
2367
out:
2368
	mnt_drop_write_file(file);
2369
	return ret;
C
Christoph Hellwig 已提交
2370 2371
}

2372
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
2373 2374 2375 2376
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2377 2378 2379
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2380 2381 2382
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
		pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
2383
		return -EINVAL;
2384 2385
	}

2386
	mutex_lock(&root->fs_info->volume_mutex);
L
Li Zefan 已提交
2387
	vol_args = memdup_user(arg, sizeof(*vol_args));
2388 2389 2390 2391
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
C
Christoph Hellwig 已提交
2392

2393
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2394 2395 2396
	ret = btrfs_init_new_device(root, vol_args->name);

	kfree(vol_args);
2397 2398
out:
	mutex_unlock(&root->fs_info->volume_mutex);
2399
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
C
Christoph Hellwig 已提交
2400 2401 2402
	return ret;
}

2403
static long btrfs_ioctl_rm_dev(struct file *file, void __user *arg)
C
Christoph Hellwig 已提交
2404
{
A
Al Viro 已提交
2405
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
C
Christoph Hellwig 已提交
2406 2407 2408
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

2409 2410 2411
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2412 2413 2414
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
Y
Yan Zheng 已提交
2415

L
Li Zefan 已提交
2416
	vol_args = memdup_user(arg, sizeof(*vol_args));
2417 2418 2419 2420
	if (IS_ERR(vol_args)) {
		ret = PTR_ERR(vol_args);
		goto out;
	}
C
Christoph Hellwig 已提交
2421

2422
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
2423

2424 2425 2426 2427 2428 2429 2430 2431
	if (atomic_xchg(&root->fs_info->mutually_exclusive_operation_running,
			1)) {
		ret = BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS;
		goto out;
	}

	mutex_lock(&root->fs_info->volume_mutex);
	ret = btrfs_rm_device(root, vol_args->name);
2432
	mutex_unlock(&root->fs_info->volume_mutex);
2433
	atomic_set(&root->fs_info->mutually_exclusive_operation_running, 0);
2434 2435 2436

out:
	kfree(vol_args);
2437
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
2438 2439 2440
	return ret;
}

J
Jan Schmidt 已提交
2441 2442
static long btrfs_ioctl_fs_info(struct btrfs_root *root, void __user *arg)
{
2443
	struct btrfs_ioctl_fs_info_args *fi_args;
J
Jan Schmidt 已提交
2444 2445 2446
	struct btrfs_device *device;
	struct btrfs_device *next;
	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
2447
	int ret = 0;
J
Jan Schmidt 已提交
2448 2449 2450 2451

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

2452 2453 2454 2455 2456 2457
	fi_args = kzalloc(sizeof(*fi_args), GFP_KERNEL);
	if (!fi_args)
		return -ENOMEM;

	fi_args->num_devices = fs_devices->num_devices;
	memcpy(&fi_args->fsid, root->fs_info->fsid, sizeof(fi_args->fsid));
J
Jan Schmidt 已提交
2458 2459 2460

	mutex_lock(&fs_devices->device_list_mutex);
	list_for_each_entry_safe(device, next, &fs_devices->devices, dev_list) {
2461 2462
		if (device->devid > fi_args->max_id)
			fi_args->max_id = device->devid;
J
Jan Schmidt 已提交
2463 2464 2465
	}
	mutex_unlock(&fs_devices->device_list_mutex);

2466 2467
	if (copy_to_user(arg, fi_args, sizeof(*fi_args)))
		ret = -EFAULT;
J
Jan Schmidt 已提交
2468

2469 2470
	kfree(fi_args);
	return ret;
J
Jan Schmidt 已提交
2471 2472 2473 2474 2475 2476 2477 2478 2479 2480 2481 2482 2483 2484 2485 2486 2487
}

static long btrfs_ioctl_dev_info(struct btrfs_root *root, void __user *arg)
{
	struct btrfs_ioctl_dev_info_args *di_args;
	struct btrfs_device *dev;
	struct btrfs_fs_devices *fs_devices = root->fs_info->fs_devices;
	int ret = 0;
	char *s_uuid = NULL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	di_args = memdup_user(arg, sizeof(*di_args));
	if (IS_ERR(di_args))
		return PTR_ERR(di_args);

2488
	if (!btrfs_is_empty_uuid(di_args->uuid))
J
Jan Schmidt 已提交
2489 2490 2491
		s_uuid = di_args->uuid;

	mutex_lock(&fs_devices->device_list_mutex);
2492
	dev = btrfs_find_device(root->fs_info, di_args->devid, s_uuid, NULL);
J
Jan Schmidt 已提交
2493 2494 2495 2496 2497 2498 2499 2500 2501 2502

	if (!dev) {
		ret = -ENODEV;
		goto out;
	}

	di_args->devid = dev->devid;
	di_args->bytes_used = dev->bytes_used;
	di_args->total_bytes = dev->total_bytes;
	memcpy(di_args->uuid, dev->uuid, sizeof(di_args->uuid));
2503
	if (dev->name) {
2504 2505 2506 2507 2508 2509
		struct rcu_string *name;

		rcu_read_lock();
		name = rcu_dereference(dev->name);
		strncpy(di_args->path, name->str, sizeof(di_args->path));
		rcu_read_unlock();
2510 2511
		di_args->path[sizeof(di_args->path) - 1] = 0;
	} else {
2512
		di_args->path[0] = '\0';
2513
	}
J
Jan Schmidt 已提交
2514 2515

out:
2516
	mutex_unlock(&fs_devices->device_list_mutex);
J
Jan Schmidt 已提交
2517 2518 2519 2520 2521 2522 2523
	if (ret == 0 && copy_to_user(arg, di_args, sizeof(*di_args)))
		ret = -EFAULT;

	kfree(di_args);
	return ret;
}

M
Mark Fasheh 已提交
2524 2525 2526 2527 2528 2529 2530 2531 2532 2533 2534 2535 2536 2537 2538 2539 2540 2541 2542 2543 2544 2545 2546 2547 2548 2549 2550 2551
static struct page *extent_same_get_page(struct inode *inode, u64 off)
{
	struct page *page;
	pgoff_t index;
	struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;

	index = off >> PAGE_CACHE_SHIFT;

	page = grab_cache_page(inode->i_mapping, index);
	if (!page)
		return NULL;

	if (!PageUptodate(page)) {
		if (extent_read_full_page_nolock(tree, page, btrfs_get_extent,
						 0))
			return NULL;
		lock_page(page);
		if (!PageUptodate(page)) {
			unlock_page(page);
			page_cache_release(page);
			return NULL;
		}
	}
	unlock_page(page);

	return page;
}

2552 2553 2554 2555 2556 2557 2558 2559 2560 2561 2562 2563 2564 2565 2566 2567 2568 2569 2570 2571
static inline void lock_extent_range(struct inode *inode, u64 off, u64 len)
{
	/* do any pending delalloc/csum calc on src, one way or
	   another, and lock file content */
	while (1) {
		struct btrfs_ordered_extent *ordered;
		lock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
		ordered = btrfs_lookup_first_ordered_extent(inode,
							    off + len - 1);
		if (!ordered &&
		    !test_range_bit(&BTRFS_I(inode)->io_tree, off,
				    off + len - 1, EXTENT_DELALLOC, 0, NULL))
			break;
		unlock_extent(&BTRFS_I(inode)->io_tree, off, off + len - 1);
		if (ordered)
			btrfs_put_ordered_extent(ordered);
		btrfs_wait_ordered_range(inode, off, len);
	}
}

M
Mark Fasheh 已提交
2572 2573 2574 2575 2576 2577 2578 2579 2580 2581 2582 2583 2584 2585 2586 2587 2588 2589 2590 2591 2592 2593 2594 2595 2596 2597 2598 2599 2600 2601 2602 2603 2604 2605 2606 2607 2608 2609 2610 2611 2612 2613 2614 2615 2616 2617 2618 2619 2620 2621 2622 2623 2624 2625 2626 2627 2628 2629 2630 2631 2632 2633 2634 2635 2636 2637 2638 2639 2640 2641 2642 2643 2644 2645 2646 2647 2648 2649 2650 2651 2652 2653 2654 2655 2656 2657 2658 2659 2660 2661 2662 2663 2664 2665 2666 2667 2668 2669 2670 2671 2672 2673 2674 2675 2676 2677 2678 2679 2680 2681 2682 2683 2684 2685 2686 2687 2688 2689 2690 2691 2692 2693 2694 2695 2696 2697 2698 2699 2700 2701 2702 2703 2704 2705 2706 2707 2708 2709 2710 2711 2712 2713 2714 2715 2716 2717 2718 2719 2720 2721 2722 2723 2724 2725 2726 2727 2728 2729 2730 2731 2732 2733 2734 2735 2736 2737 2738 2739 2740 2741 2742 2743 2744 2745 2746 2747 2748 2749 2750 2751 2752 2753 2754 2755 2756 2757 2758 2759 2760 2761 2762 2763 2764 2765 2766 2767 2768 2769 2770 2771 2772 2773 2774 2775 2776 2777 2778 2779 2780 2781 2782 2783 2784 2785 2786 2787 2788 2789 2790 2791 2792 2793 2794 2795 2796 2797 2798 2799 2800 2801 2802 2803 2804 2805 2806 2807 2808 2809 2810 2811 2812 2813 2814 2815 2816
static void btrfs_double_unlock(struct inode *inode1, u64 loff1,
				struct inode *inode2, u64 loff2, u64 len)
{
	unlock_extent(&BTRFS_I(inode1)->io_tree, loff1, loff1 + len - 1);
	unlock_extent(&BTRFS_I(inode2)->io_tree, loff2, loff2 + len - 1);

	mutex_unlock(&inode1->i_mutex);
	mutex_unlock(&inode2->i_mutex);
}

static void btrfs_double_lock(struct inode *inode1, u64 loff1,
			      struct inode *inode2, u64 loff2, u64 len)
{
	if (inode1 < inode2) {
		swap(inode1, inode2);
		swap(loff1, loff2);
	}

	mutex_lock_nested(&inode1->i_mutex, I_MUTEX_PARENT);
	lock_extent_range(inode1, loff1, len);
	if (inode1 != inode2) {
		mutex_lock_nested(&inode2->i_mutex, I_MUTEX_CHILD);
		lock_extent_range(inode2, loff2, len);
	}
}

static int btrfs_cmp_data(struct inode *src, u64 loff, struct inode *dst,
			  u64 dst_loff, u64 len)
{
	int ret = 0;
	struct page *src_page, *dst_page;
	unsigned int cmp_len = PAGE_CACHE_SIZE;
	void *addr, *dst_addr;

	while (len) {
		if (len < PAGE_CACHE_SIZE)
			cmp_len = len;

		src_page = extent_same_get_page(src, loff);
		if (!src_page)
			return -EINVAL;
		dst_page = extent_same_get_page(dst, dst_loff);
		if (!dst_page) {
			page_cache_release(src_page);
			return -EINVAL;
		}
		addr = kmap_atomic(src_page);
		dst_addr = kmap_atomic(dst_page);

		flush_dcache_page(src_page);
		flush_dcache_page(dst_page);

		if (memcmp(addr, dst_addr, cmp_len))
			ret = BTRFS_SAME_DATA_DIFFERS;

		kunmap_atomic(addr);
		kunmap_atomic(dst_addr);
		page_cache_release(src_page);
		page_cache_release(dst_page);

		if (ret)
			break;

		loff += cmp_len;
		dst_loff += cmp_len;
		len -= cmp_len;
	}

	return ret;
}

static int extent_same_check_offsets(struct inode *inode, u64 off, u64 len)
{
	u64 bs = BTRFS_I(inode)->root->fs_info->sb->s_blocksize;

	if (off + len > inode->i_size || off + len < off)
		return -EINVAL;
	/* Check that we are block aligned - btrfs_clone() requires this */
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs))
		return -EINVAL;

	return 0;
}

static int btrfs_extent_same(struct inode *src, u64 loff, u64 len,
			     struct inode *dst, u64 dst_loff)
{
	int ret;

	/*
	 * btrfs_clone() can't handle extents in the same file
	 * yet. Once that works, we can drop this check and replace it
	 * with a check for the same inode, but overlapping extents.
	 */
	if (src == dst)
		return -EINVAL;

	btrfs_double_lock(src, loff, dst, dst_loff, len);

	ret = extent_same_check_offsets(src, loff, len);
	if (ret)
		goto out_unlock;

	ret = extent_same_check_offsets(dst, dst_loff, len);
	if (ret)
		goto out_unlock;

	/* don't make the dst file partly checksummed */
	if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
	    (BTRFS_I(dst)->flags & BTRFS_INODE_NODATASUM)) {
		ret = -EINVAL;
		goto out_unlock;
	}

	ret = btrfs_cmp_data(src, loff, dst, dst_loff, len);
	if (ret == 0)
		ret = btrfs_clone(src, dst, loff, len, len, dst_loff);

out_unlock:
	btrfs_double_unlock(src, loff, dst, dst_loff, len);

	return ret;
}

#define BTRFS_MAX_DEDUPE_LEN	(16 * 1024 * 1024)

static long btrfs_ioctl_file_extent_same(struct file *file,
					 void __user *argp)
{
	struct btrfs_ioctl_same_args *args = argp;
	struct btrfs_ioctl_same_args same;
	struct btrfs_ioctl_same_extent_info info;
	struct inode *src = file->f_dentry->d_inode;
	struct file *dst_file = NULL;
	struct inode *dst;
	u64 off;
	u64 len;
	int i;
	int ret;
	u64 bs = BTRFS_I(src)->root->fs_info->sb->s_blocksize;
	bool is_admin = capable(CAP_SYS_ADMIN);

	if (!(file->f_mode & FMODE_READ))
		return -EINVAL;

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	if (copy_from_user(&same,
			   (struct btrfs_ioctl_same_args __user *)argp,
			   sizeof(same))) {
		ret = -EFAULT;
		goto out;
	}

	off = same.logical_offset;
	len = same.length;

	/*
	 * Limit the total length we will dedupe for each operation.
	 * This is intended to bound the total time spent in this
	 * ioctl to something sane.
	 */
	if (len > BTRFS_MAX_DEDUPE_LEN)
		len = BTRFS_MAX_DEDUPE_LEN;

	if (WARN_ON_ONCE(bs < PAGE_CACHE_SIZE)) {
		/*
		 * Btrfs does not support blocksize < page_size. As a
		 * result, btrfs_cmp_data() won't correctly handle
		 * this situation without an update.
		 */
		ret = -EINVAL;
		goto out;
	}

	ret = -EISDIR;
	if (S_ISDIR(src->i_mode))
		goto out;

	ret = -EACCES;
	if (!S_ISREG(src->i_mode))
		goto out;

	ret = 0;
	for (i = 0; i < same.dest_count; i++) {
		if (copy_from_user(&info, &args->info[i], sizeof(info))) {
			ret = -EFAULT;
			goto out;
		}

		info.bytes_deduped = 0;

		dst_file = fget(info.fd);
		if (!dst_file) {
			info.status = -EBADF;
			goto next;
		}

		if (!(is_admin || (dst_file->f_mode & FMODE_WRITE))) {
			info.status = -EINVAL;
			goto next;
		}

		info.status = -EXDEV;
		if (file->f_path.mnt != dst_file->f_path.mnt)
			goto next;

		dst = dst_file->f_dentry->d_inode;
		if (src->i_sb != dst->i_sb)
			goto next;

		if (S_ISDIR(dst->i_mode)) {
			info.status = -EISDIR;
			goto next;
		}

		if (!S_ISREG(dst->i_mode)) {
			info.status = -EACCES;
			goto next;
		}

		info.status = btrfs_extent_same(src, off, len, dst,
						info.logical_offset);
		if (info.status == 0)
			info.bytes_deduped += len;

next:
		if (dst_file)
			fput(dst_file);

		if (__put_user_unaligned(info.status, &args->info[i].status) ||
		    __put_user_unaligned(info.bytes_deduped,
					 &args->info[i].bytes_deduped)) {
			ret = -EFAULT;
			goto out;
		}                                                               
	}

out:
	mnt_drop_write_file(file);
	return ret;
}

2817 2818 2819 2820 2821 2822 2823 2824 2825 2826 2827 2828 2829
/**
 * btrfs_clone() - clone a range from inode file to another
 *
 * @src: Inode to clone from
 * @inode: Inode to clone to
 * @off: Offset within source to start clone from
 * @olen: Original length, passed by user, of range to clone
 * @olen_aligned: Block-aligned value of olen, extent_same uses
 *               identical values here
 * @destoff: Offset within @inode to start clone
 */
static int btrfs_clone(struct inode *src, struct inode *inode,
		       u64 off, u64 olen, u64 olen_aligned, u64 destoff)
C
Christoph Hellwig 已提交
2830 2831
{
	struct btrfs_root *root = BTRFS_I(inode)->root;
2832
	struct btrfs_path *path = NULL;
C
Christoph Hellwig 已提交
2833
	struct extent_buffer *leaf;
2834 2835
	struct btrfs_trans_handle *trans;
	char *buf = NULL;
Y
Yan Zheng 已提交
2836
	struct btrfs_key key;
C
Christoph Hellwig 已提交
2837 2838
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
2839
	int ret;
2840
	u64 len = olen_aligned;
Y
Yan Zheng 已提交
2841 2842 2843 2844

	ret = -ENOMEM;
	buf = vmalloc(btrfs_level_size(root, 0));
	if (!buf)
2845
		return ret;
Y
Yan Zheng 已提交
2846 2847 2848 2849

	path = btrfs_alloc_path();
	if (!path) {
		vfree(buf);
2850
		return ret;
2851 2852
	}

2853
	path->reada = 2;
2854
	/* clone data */
L
Li Zefan 已提交
2855
	key.objectid = btrfs_ino(src);
Y
Yan Zheng 已提交
2856 2857
	key.type = BTRFS_EXTENT_DATA_KEY;
	key.offset = 0;
C
Christoph Hellwig 已提交
2858 2859 2860 2861 2862 2863

	while (1) {
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
2864 2865
		ret = btrfs_search_slot(NULL, BTRFS_I(src)->root, &key, path,
				0, 0);
C
Christoph Hellwig 已提交
2866 2867 2868
		if (ret < 0)
			goto out;

Y
Yan Zheng 已提交
2869 2870
		nritems = btrfs_header_nritems(path->nodes[0]);
		if (path->slots[0] >= nritems) {
2871
			ret = btrfs_next_leaf(BTRFS_I(src)->root, path);
C
Christoph Hellwig 已提交
2872 2873 2874 2875
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
2876
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
2877 2878 2879 2880
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
2881
		btrfs_item_key_to_cpu(leaf, &key, slot);
2882
		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
L
Li Zefan 已提交
2883
		    key.objectid != btrfs_ino(src))
C
Christoph Hellwig 已提交
2884 2885
			break;

2886 2887 2888
		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
2889 2890
			u32 size;
			struct btrfs_key new_key;
2891 2892 2893
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
2894
			u64 endoff;
Z
Zheng Yan 已提交
2895 2896 2897 2898 2899

			size = btrfs_item_size_nr(leaf, slot);
			read_extent_buffer(leaf, buf,
					   btrfs_item_ptr_offset(leaf, slot),
					   size);
2900 2901 2902 2903 2904

			extent = btrfs_item_ptr(leaf, slot,
						struct btrfs_file_extent_item);
			comp = btrfs_file_extent_compression(leaf, extent);
			type = btrfs_file_extent_type(leaf, extent);
2905 2906
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
2907 2908 2909 2910
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
2911
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
2912 2913
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
2914 2915 2916 2917 2918
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				/* take upper bound, may be compressed */
				datal = btrfs_file_extent_ram_bytes(leaf,
								    extent);
			}
2919
			btrfs_release_path(path);
Z
Zheng Yan 已提交
2920

2921
			if (key.offset + datal <= off ||
L
Liu Bo 已提交
2922
			    key.offset >= off + len - 1)
2923 2924
				goto next;

Z
Zheng Yan 已提交
2925
			memcpy(&new_key, &key, sizeof(new_key));
L
Li Zefan 已提交
2926
			new_key.objectid = btrfs_ino(inode);
2927 2928 2929 2930
			if (off <= key.offset)
				new_key.offset = key.offset + destoff - off;
			else
				new_key.offset = destoff;
Z
Zheng Yan 已提交
2931

2932 2933 2934 2935 2936 2937
			/*
			 * 1 - adjusting old extent (we may have to split it)
			 * 1 - add new extent
			 * 1 - inode update
			 */
			trans = btrfs_start_transaction(root, 3);
2938 2939 2940 2941 2942
			if (IS_ERR(trans)) {
				ret = PTR_ERR(trans);
				goto out;
			}

2943 2944
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
2945 2946 2947 2948 2949 2950 2951 2952 2953 2954
				/*
				 *    a  | --- range to clone ---|  b
				 * | ------------- extent ------------- |
				 */

				/* substract range b */
				if (key.offset + datal > off + len)
					datal = off + len - key.offset;

				/* substract range a */
2955 2956 2957 2958 2959
				if (off > key.offset) {
					datao += off - key.offset;
					datal -= off - key.offset;
				}

J
Josef Bacik 已提交
2960
				ret = btrfs_drop_extents(trans, root, inode,
2961 2962
							 new_key.offset,
							 new_key.offset + datal,
2963
							 1);
2964 2965 2966 2967 2968 2969
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
2970

2971 2972
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
2973 2974 2975 2976 2977 2978
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
2979 2980 2981 2982

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
2983 2984
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
2985

2986
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
2987
						struct btrfs_file_extent_item);
2988 2989 2990 2991 2992 2993 2994 2995 2996 2997 2998

				/* disko == 0 means it's a hole */
				if (!disko)
					datao = 0;

				btrfs_set_file_extent_offset(leaf, extent,
							     datao);
				btrfs_set_file_extent_num_bytes(leaf, extent,
								datal);
				if (disko) {
					inode_add_bytes(inode, datal);
Y
Yan Zheng 已提交
2999
					ret = btrfs_inc_extent_ref(trans, root,
3000 3001
							disko, diskl, 0,
							root->root_key.objectid,
L
Li Zefan 已提交
3002
							btrfs_ino(inode),
A
Arne Jansen 已提交
3003 3004
							new_key.offset - datao,
							0);
3005 3006 3007 3008 3009 3010 3011 3012 3013
					if (ret) {
						btrfs_abort_transaction(trans,
									root,
									ret);
						btrfs_end_transaction(trans,
								      root);
						goto out;

					}
C
Christoph Hellwig 已提交
3014
				}
3015 3016 3017 3018 3019 3020 3021
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				u64 skip = 0;
				u64 trim = 0;
				if (off > key.offset) {
					skip = off - key.offset;
					new_key.offset += skip;
				}
C
Chris Mason 已提交
3022

L
Liu Bo 已提交
3023 3024
				if (key.offset + datal > off + len)
					trim = key.offset + datal - (off + len);
C
Chris Mason 已提交
3025

3026 3027
				if (comp && (skip || trim)) {
					ret = -EINVAL;
3028
					btrfs_end_transaction(trans, root);
3029 3030 3031 3032
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
3033

J
Josef Bacik 已提交
3034
				ret = btrfs_drop_extents(trans, root, inode,
3035 3036
							 new_key.offset,
							 new_key.offset + datal,
3037
							 1);
3038 3039 3040 3041 3042 3043
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3044

3045 3046
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
3047 3048 3049 3050 3051 3052
				if (ret) {
					btrfs_abort_transaction(trans, root,
								ret);
					btrfs_end_transaction(trans, root);
					goto out;
				}
3053 3054

				if (skip) {
C
Chris Mason 已提交
3055 3056
					u32 start =
					  btrfs_file_extent_calc_inline_size(0);
3057 3058 3059 3060 3061 3062 3063 3064 3065 3066
					memmove(buf+start, buf+start+skip,
						datal);
				}

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
				inode_add_bytes(inode, datal);
C
Christoph Hellwig 已提交
3067
			}
3068 3069

			btrfs_mark_buffer_dirty(leaf);
3070
			btrfs_release_path(path);
3071

3072
			inode_inc_iversion(inode);
3073
			inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3074 3075 3076 3077 3078 3079 3080

			/*
			 * we round up to the block size at eof when
			 * determining which extents to clone above,
			 * but shouldn't round up the file size
			 */
			endoff = new_key.offset + datal;
3081 3082
			if (endoff > destoff+olen)
				endoff = destoff+olen;
3083 3084 3085
			if (endoff > inode->i_size)
				btrfs_i_size_write(inode, endoff);

3086
			ret = btrfs_update_inode(trans, root, inode);
3087 3088 3089 3090 3091 3092
			if (ret) {
				btrfs_abort_transaction(trans, root, ret);
				btrfs_end_transaction(trans, root);
				goto out;
			}
			ret = btrfs_end_transaction(trans, root);
3093
		}
C
Chris Mason 已提交
3094
next:
3095
		btrfs_release_path(path);
C
Christoph Hellwig 已提交
3096 3097 3098
		key.offset++;
	}
	ret = 0;
3099

C
Christoph Hellwig 已提交
3100
out:
3101
	btrfs_release_path(path);
3102 3103 3104 3105 3106 3107 3108 3109 3110 3111 3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 3132 3133 3134 3135 3136 3137 3138 3139 3140 3141 3142 3143 3144 3145 3146 3147 3148 3149 3150 3151 3152 3153 3154 3155 3156 3157 3158 3159 3160 3161 3162 3163 3164 3165 3166 3167 3168 3169 3170 3171 3172 3173 3174 3175 3176 3177 3178 3179 3180 3181 3182 3183 3184 3185 3186 3187 3188 3189 3190 3191 3192 3193 3194 3195 3196 3197 3198 3199 3200 3201 3202 3203 3204 3205 3206 3207 3208 3209 3210 3211 3212 3213 3214 3215 3216 3217 3218 3219
	btrfs_free_path(path);
	vfree(buf);
	return ret;
}

static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
				       u64 off, u64 olen, u64 destoff)
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct fd src_file;
	struct inode *src;
	int ret;
	u64 len = olen;
	u64 bs = root->fs_info->sb->s_blocksize;
	int same_inode = 0;

	/*
	 * TODO:
	 * - split compressed inline extents.  annoying: we need to
	 *   decompress into destination's address_space (the file offset
	 *   may change, so source mapping won't do), then recompress (or
	 *   otherwise reinsert) a subrange.
	 * - allow ranges within the same file to be cloned (provided
	 *   they don't overlap)?
	 */

	/* the destination must be opened for writing */
	if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
		return -EINVAL;

	if (btrfs_root_readonly(root))
		return -EROFS;

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	src_file = fdget(srcfd);
	if (!src_file.file) {
		ret = -EBADF;
		goto out_drop_write;
	}

	ret = -EXDEV;
	if (src_file.file->f_path.mnt != file->f_path.mnt)
		goto out_fput;

	src = file_inode(src_file.file);

	ret = -EINVAL;
	if (src == inode)
		same_inode = 1;

	/* the src must be open for reading */
	if (!(src_file.file->f_mode & FMODE_READ))
		goto out_fput;

	/* don't make the dst file partly checksummed */
	if ((BTRFS_I(src)->flags & BTRFS_INODE_NODATASUM) !=
	    (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
		goto out_fput;

	ret = -EISDIR;
	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
		goto out_fput;

	ret = -EXDEV;
	if (src->i_sb != inode->i_sb)
		goto out_fput;

	if (!same_inode) {
		if (inode < src) {
			mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
			mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
		} else {
			mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
			mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
		}
	} else {
		mutex_lock(&src->i_mutex);
	}

	/* determine range to clone */
	ret = -EINVAL;
	if (off + len > src->i_size || off + len < off)
		goto out_unlock;
	if (len == 0)
		olen = len = src->i_size - off;
	/* if we extend to eof, continue to block boundary */
	if (off + len == src->i_size)
		len = ALIGN(src->i_size, bs) - off;

	/* verify the end result is block aligned */
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
	    !IS_ALIGNED(destoff, bs))
		goto out_unlock;

	/* verify if ranges are overlapped within the same file */
	if (same_inode) {
		if (destoff + len > off && destoff < off + len)
			goto out_unlock;
	}

	if (destoff > inode->i_size) {
		ret = btrfs_cont_expand(inode, inode->i_size, destoff);
		if (ret)
			goto out_unlock;
	}

	/* truncate page cache pages from target inode range */
	truncate_inode_pages_range(&inode->i_data, destoff,
				   PAGE_CACHE_ALIGN(destoff + len) - 1);

	lock_extent_range(src, off, len);

	ret = btrfs_clone(src, inode, off, olen, len, destoff);

L
Liu Bo 已提交
3220
	unlock_extent(&BTRFS_I(src)->io_tree, off, off + len - 1);
C
Christoph Hellwig 已提交
3221 3222
out_unlock:
	mutex_unlock(&src->i_mutex);
3223 3224
	if (!same_inode)
		mutex_unlock(&inode->i_mutex);
C
Christoph Hellwig 已提交
3225
out_fput:
3226
	fdput(src_file);
3227
out_drop_write:
A
Al Viro 已提交
3228
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
3229 3230 3231
	return ret;
}

3232
static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
3233 3234 3235
{
	struct btrfs_ioctl_clone_range_args args;

3236
	if (copy_from_user(&args, argp, sizeof(args)))
3237 3238 3239 3240 3241
		return -EFAULT;
	return btrfs_ioctl_clone(file, args.src_fd, args.src_offset,
				 args.src_length, args.dest_offset);
}

C
Christoph Hellwig 已提交
3242 3243 3244 3245 3246 3247
/*
 * there are many ways the trans_start and trans_end ioctls can lead
 * to deadlocks.  They should only be used by applications that
 * basically own the machine, and have a very in depth understanding
 * of all the possible deadlocks and enospc problems.
 */
3248
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
3249
{
A
Al Viro 已提交
3250
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
3251 3252
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
3253
	int ret;
C
Christoph Hellwig 已提交
3254

3255
	ret = -EPERM;
3256
	if (!capable(CAP_SYS_ADMIN))
3257
		goto out;
3258

3259 3260
	ret = -EINPROGRESS;
	if (file->private_data)
C
Christoph Hellwig 已提交
3261
		goto out;
3262

L
Li Zefan 已提交
3263 3264 3265 3266
	ret = -EROFS;
	if (btrfs_root_readonly(root))
		goto out;

3267
	ret = mnt_want_write_file(file);
Y
Yan Zheng 已提交
3268 3269 3270
	if (ret)
		goto out;

J
Josef Bacik 已提交
3271
	atomic_inc(&root->fs_info->open_ioctl_trans);
3272

3273
	ret = -ENOMEM;
3274
	trans = btrfs_start_ioctl_transaction(root);
3275
	if (IS_ERR(trans))
3276 3277 3278 3279 3280 3281
		goto out_drop;

	file->private_data = trans;
	return 0;

out_drop:
J
Josef Bacik 已提交
3282
	atomic_dec(&root->fs_info->open_ioctl_trans);
A
Al Viro 已提交
3283
	mnt_drop_write_file(file);
C
Christoph Hellwig 已提交
3284 3285 3286 3287
out:
	return ret;
}

3288 3289
static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
{
A
Al Viro 已提交
3290
	struct inode *inode = file_inode(file);
3291 3292 3293 3294 3295 3296 3297 3298 3299
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_root *new_root;
	struct btrfs_dir_item *di;
	struct btrfs_trans_handle *trans;
	struct btrfs_path *path;
	struct btrfs_key location;
	struct btrfs_disk_key disk_key;
	u64 objectid = 0;
	u64 dir_id;
3300
	int ret;
3301 3302 3303 3304

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

3305 3306 3307 3308 3309 3310 3311 3312
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	if (copy_from_user(&objectid, argp, sizeof(objectid))) {
		ret = -EFAULT;
		goto out;
	}
3313 3314 3315 3316 3317 3318 3319 3320 3321

	if (!objectid)
		objectid = root->root_key.objectid;

	location.objectid = objectid;
	location.type = BTRFS_ROOT_ITEM_KEY;
	location.offset = (u64)-1;

	new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
3322 3323 3324 3325
	if (IS_ERR(new_root)) {
		ret = PTR_ERR(new_root);
		goto out;
	}
3326 3327

	path = btrfs_alloc_path();
3328 3329 3330 3331
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}
3332 3333 3334
	path->leave_spinning = 1;

	trans = btrfs_start_transaction(root, 1);
3335
	if (IS_ERR(trans)) {
3336
		btrfs_free_path(path);
3337 3338
		ret = PTR_ERR(trans);
		goto out;
3339 3340
	}

3341
	dir_id = btrfs_super_root_dir(root->fs_info->super_copy);
3342 3343
	di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 1);
3344
	if (IS_ERR_OR_NULL(di)) {
3345 3346 3347 3348
		btrfs_free_path(path);
		btrfs_end_transaction(trans, root);
		printk(KERN_ERR "Umm, you don't have the default dir item, "
		       "this isn't going to work\n");
3349 3350
		ret = -ENOENT;
		goto out;
3351 3352 3353 3354 3355 3356 3357
	}

	btrfs_cpu_key_to_disk(&disk_key, &new_root->root_key);
	btrfs_set_dir_item_key(path->nodes[0], di, &disk_key);
	btrfs_mark_buffer_dirty(path->nodes[0]);
	btrfs_free_path(path);

3358
	btrfs_set_fs_incompat(root->fs_info, DEFAULT_SUBVOL);
3359
	btrfs_end_transaction(trans, root);
3360 3361 3362
out:
	mnt_drop_write_file(file);
	return ret;
3363 3364
}

3365 3366
void btrfs_get_block_group_info(struct list_head *groups_list,
				struct btrfs_ioctl_space_info *space)
3367 3368 3369 3370 3371 3372 3373 3374 3375 3376 3377 3378 3379 3380
{
	struct btrfs_block_group_cache *block_group;

	space->total_bytes = 0;
	space->used_bytes = 0;
	space->flags = 0;
	list_for_each_entry(block_group, groups_list, list) {
		space->flags = block_group->flags;
		space->total_bytes += block_group->key.offset;
		space->used_bytes +=
			btrfs_block_group_used(&block_group->item);
	}
}

3381
static long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
J
Josef Bacik 已提交
3382 3383 3384 3385
{
	struct btrfs_ioctl_space_args space_args;
	struct btrfs_ioctl_space_info space;
	struct btrfs_ioctl_space_info *dest;
3386
	struct btrfs_ioctl_space_info *dest_orig;
3387
	struct btrfs_ioctl_space_info __user *user_dest;
J
Josef Bacik 已提交
3388
	struct btrfs_space_info *info;
3389 3390 3391 3392 3393
	u64 types[] = {BTRFS_BLOCK_GROUP_DATA,
		       BTRFS_BLOCK_GROUP_SYSTEM,
		       BTRFS_BLOCK_GROUP_METADATA,
		       BTRFS_BLOCK_GROUP_DATA | BTRFS_BLOCK_GROUP_METADATA};
	int num_types = 4;
3394
	int alloc_size;
J
Josef Bacik 已提交
3395
	int ret = 0;
3396
	u64 slot_count = 0;
3397
	int i, c;
J
Josef Bacik 已提交
3398 3399 3400 3401 3402 3403

	if (copy_from_user(&space_args,
			   (struct btrfs_ioctl_space_args __user *)arg,
			   sizeof(space_args)))
		return -EFAULT;

3404 3405 3406 3407 3408 3409 3410 3411 3412 3413 3414 3415 3416 3417 3418 3419 3420 3421 3422 3423 3424 3425 3426 3427
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

		info = NULL;
		rcu_read_lock();
		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
					list) {
			if (tmp->flags == types[i]) {
				info = tmp;
				break;
			}
		}
		rcu_read_unlock();

		if (!info)
			continue;

		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c]))
				slot_count++;
		}
		up_read(&info->groups_sem);
	}
3428 3429 3430 3431 3432 3433

	/* space_slots == 0 means they are asking for a count */
	if (space_args.space_slots == 0) {
		space_args.total_spaces = slot_count;
		goto out;
	}
3434

3435
	slot_count = min_t(u64, space_args.space_slots, slot_count);
3436

3437
	alloc_size = sizeof(*dest) * slot_count;
3438

3439 3440 3441 3442 3443 3444
	/* we generally have at most 6 or so space infos, one for each raid
	 * level.  So, a whole page should be more than enough for everyone
	 */
	if (alloc_size > PAGE_CACHE_SIZE)
		return -ENOMEM;

J
Josef Bacik 已提交
3445
	space_args.total_spaces = 0;
3446 3447 3448 3449
	dest = kmalloc(alloc_size, GFP_NOFS);
	if (!dest)
		return -ENOMEM;
	dest_orig = dest;
J
Josef Bacik 已提交
3450

3451
	/* now we have a buffer to copy into */
3452 3453 3454
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

3455 3456 3457
		if (!slot_count)
			break;

3458 3459 3460 3461 3462 3463 3464 3465 3466 3467
		info = NULL;
		rcu_read_lock();
		list_for_each_entry_rcu(tmp, &root->fs_info->space_info,
					list) {
			if (tmp->flags == types[i]) {
				info = tmp;
				break;
			}
		}
		rcu_read_unlock();
3468

3469 3470 3471 3472 3473
		if (!info)
			continue;
		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c])) {
3474 3475
				btrfs_get_block_group_info(
					&info->block_groups[c], &space);
3476 3477 3478
				memcpy(dest, &space, sizeof(space));
				dest++;
				space_args.total_spaces++;
3479
				slot_count--;
3480
			}
3481 3482
			if (!slot_count)
				break;
3483 3484
		}
		up_read(&info->groups_sem);
J
Josef Bacik 已提交
3485 3486
	}

D
Daniel J Blueman 已提交
3487
	user_dest = (struct btrfs_ioctl_space_info __user *)
3488 3489 3490 3491 3492 3493 3494 3495
		(arg + sizeof(struct btrfs_ioctl_space_args));

	if (copy_to_user(user_dest, dest_orig, alloc_size))
		ret = -EFAULT;

	kfree(dest_orig);
out:
	if (ret == 0 && copy_to_user(arg, &space_args, sizeof(space_args)))
J
Josef Bacik 已提交
3496 3497 3498 3499 3500
		ret = -EFAULT;

	return ret;
}

C
Christoph Hellwig 已提交
3501 3502 3503 3504 3505 3506 3507 3508
/*
 * there are many ways the trans_start and trans_end ioctls can lead
 * to deadlocks.  They should only be used by applications that
 * basically own the machine, and have a very in depth understanding
 * of all the possible deadlocks and enospc problems.
 */
long btrfs_ioctl_trans_end(struct file *file)
{
A
Al Viro 已提交
3509
	struct inode *inode = file_inode(file);
C
Christoph Hellwig 已提交
3510 3511 3512 3513
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;

	trans = file->private_data;
3514 3515
	if (!trans)
		return -EINVAL;
C
Christoph Hellwig 已提交
3516
	file->private_data = NULL;
3517

3518 3519
	btrfs_end_transaction(trans, root);

J
Josef Bacik 已提交
3520
	atomic_dec(&root->fs_info->open_ioctl_trans);
3521

A
Al Viro 已提交
3522
	mnt_drop_write_file(file);
3523
	return 0;
C
Christoph Hellwig 已提交
3524 3525
}

3526 3527
static noinline long btrfs_ioctl_start_sync(struct btrfs_root *root,
					    void __user *argp)
3528 3529 3530
{
	struct btrfs_trans_handle *trans;
	u64 transid;
T
Tsutomu Itoh 已提交
3531
	int ret;
3532

M
Miao Xie 已提交
3533
	trans = btrfs_attach_transaction_barrier(root);
3534 3535 3536 3537 3538 3539 3540 3541
	if (IS_ERR(trans)) {
		if (PTR_ERR(trans) != -ENOENT)
			return PTR_ERR(trans);

		/* No running transaction, don't bother */
		transid = root->fs_info->last_trans_committed;
		goto out;
	}
3542
	transid = trans->transid;
T
Tsutomu Itoh 已提交
3543
	ret = btrfs_commit_transaction_async(trans, root, 0);
3544 3545
	if (ret) {
		btrfs_end_transaction(trans, root);
T
Tsutomu Itoh 已提交
3546
		return ret;
3547
	}
3548
out:
3549 3550 3551 3552 3553 3554
	if (argp)
		if (copy_to_user(argp, &transid, sizeof(transid)))
			return -EFAULT;
	return 0;
}

3555 3556
static noinline long btrfs_ioctl_wait_sync(struct btrfs_root *root,
					   void __user *argp)
3557 3558 3559 3560 3561 3562 3563 3564 3565 3566 3567 3568
{
	u64 transid;

	if (argp) {
		if (copy_from_user(&transid, argp, sizeof(transid)))
			return -EFAULT;
	} else {
		transid = 0;  /* current trans */
	}
	return btrfs_wait_for_commit(root, transid);
}

M
Miao Xie 已提交
3569
static long btrfs_ioctl_scrub(struct file *file, void __user *arg)
J
Jan Schmidt 已提交
3570
{
A
Al Viro 已提交
3571
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
3572
	struct btrfs_ioctl_scrub_args *sa;
M
Miao Xie 已提交
3573
	int ret;
J
Jan Schmidt 已提交
3574 3575 3576 3577 3578 3579 3580 3581

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa))
		return PTR_ERR(sa);

M
Miao Xie 已提交
3582 3583 3584 3585 3586 3587
	if (!(sa->flags & BTRFS_SCRUB_READONLY)) {
		ret = mnt_want_write_file(file);
		if (ret)
			goto out;
	}

3588
	ret = btrfs_scrub_dev(root->fs_info, sa->devid, sa->start, sa->end,
3589 3590
			      &sa->progress, sa->flags & BTRFS_SCRUB_READONLY,
			      0);
J
Jan Schmidt 已提交
3591 3592 3593 3594

	if (copy_to_user(arg, sa, sizeof(*sa)))
		ret = -EFAULT;

M
Miao Xie 已提交
3595 3596 3597
	if (!(sa->flags & BTRFS_SCRUB_READONLY))
		mnt_drop_write_file(file);
out:
J
Jan Schmidt 已提交
3598 3599 3600 3601 3602 3603 3604 3605 3606
	kfree(sa);
	return ret;
}

static long btrfs_ioctl_scrub_cancel(struct btrfs_root *root, void __user *arg)
{
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

3607
	return btrfs_scrub_cancel(root->fs_info);
J
Jan Schmidt 已提交
3608 3609 3610 3611 3612 3613 3614 3615 3616 3617 3618 3619 3620 3621 3622 3623 3624 3625 3626 3627 3628 3629 3630 3631
}

static long btrfs_ioctl_scrub_progress(struct btrfs_root *root,
				       void __user *arg)
{
	struct btrfs_ioctl_scrub_args *sa;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa))
		return PTR_ERR(sa);

	ret = btrfs_scrub_progress(root, sa->devid, &sa->progress);

	if (copy_to_user(arg, sa, sizeof(*sa)))
		ret = -EFAULT;

	kfree(sa);
	return ret;
}

3632
static long btrfs_ioctl_get_dev_stats(struct btrfs_root *root,
3633
				      void __user *arg)
3634 3635 3636 3637 3638 3639 3640 3641
{
	struct btrfs_ioctl_get_dev_stats *sa;
	int ret;

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa))
		return PTR_ERR(sa);

3642 3643 3644 3645 3646 3647
	if ((sa->flags & BTRFS_DEV_STATS_RESET) && !capable(CAP_SYS_ADMIN)) {
		kfree(sa);
		return -EPERM;
	}

	ret = btrfs_get_dev_stats(root, sa);
3648 3649 3650 3651 3652 3653 3654 3655

	if (copy_to_user(arg, sa, sizeof(*sa)))
		ret = -EFAULT;

	kfree(sa);
	return ret;
}

3656 3657 3658 3659 3660 3661 3662 3663 3664 3665 3666 3667 3668 3669
static long btrfs_ioctl_dev_replace(struct btrfs_root *root, void __user *arg)
{
	struct btrfs_ioctl_dev_replace_args *p;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	p = memdup_user(arg, sizeof(*p));
	if (IS_ERR(p))
		return PTR_ERR(p);

	switch (p->cmd) {
	case BTRFS_IOCTL_DEV_REPLACE_CMD_START:
3670 3671 3672
		if (root->fs_info->sb->s_flags & MS_RDONLY)
			return -EROFS;

3673 3674 3675 3676 3677 3678 3679 3680 3681 3682 3683 3684 3685 3686 3687 3688 3689 3690 3691 3692 3693 3694 3695 3696 3697 3698 3699 3700 3701 3702 3703
		if (atomic_xchg(
			&root->fs_info->mutually_exclusive_operation_running,
			1)) {
			pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
			ret = -EINPROGRESS;
		} else {
			ret = btrfs_dev_replace_start(root, p);
			atomic_set(
			 &root->fs_info->mutually_exclusive_operation_running,
			 0);
		}
		break;
	case BTRFS_IOCTL_DEV_REPLACE_CMD_STATUS:
		btrfs_dev_replace_status(root->fs_info, p);
		ret = 0;
		break;
	case BTRFS_IOCTL_DEV_REPLACE_CMD_CANCEL:
		ret = btrfs_dev_replace_cancel(root->fs_info, p);
		break;
	default:
		ret = -EINVAL;
		break;
	}

	if (copy_to_user(arg, p, sizeof(*p)))
		ret = -EFAULT;

	kfree(p);
	return ret;
}

3704 3705 3706 3707
static long btrfs_ioctl_ino_to_path(struct btrfs_root *root, void __user *arg)
{
	int ret = 0;
	int i;
3708
	u64 rel_ptr;
3709
	int size;
3710
	struct btrfs_ioctl_ino_path_args *ipa = NULL;
3711 3712 3713
	struct inode_fs_paths *ipath = NULL;
	struct btrfs_path *path;

3714
	if (!capable(CAP_DAC_READ_SEARCH))
3715 3716 3717 3718 3719 3720 3721 3722 3723 3724 3725 3726 3727 3728 3729 3730 3731 3732 3733 3734 3735 3736 3737 3738 3739 3740 3741 3742
		return -EPERM;

	path = btrfs_alloc_path();
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}

	ipa = memdup_user(arg, sizeof(*ipa));
	if (IS_ERR(ipa)) {
		ret = PTR_ERR(ipa);
		ipa = NULL;
		goto out;
	}

	size = min_t(u32, ipa->size, 4096);
	ipath = init_ipath(size, root, path);
	if (IS_ERR(ipath)) {
		ret = PTR_ERR(ipath);
		ipath = NULL;
		goto out;
	}

	ret = paths_from_inode(ipa->inum, ipath);
	if (ret < 0)
		goto out;

	for (i = 0; i < ipath->fspath->elem_cnt; ++i) {
3743 3744
		rel_ptr = ipath->fspath->val[i] -
			  (u64)(unsigned long)ipath->fspath->val;
3745
		ipath->fspath->val[i] = rel_ptr;
3746 3747
	}

3748 3749
	ret = copy_to_user((void *)(unsigned long)ipa->fspath,
			   (void *)(unsigned long)ipath->fspath, size);
3750 3751 3752 3753 3754 3755 3756 3757 3758 3759 3760 3761 3762 3763 3764 3765 3766 3767 3768 3769 3770 3771 3772 3773 3774 3775 3776 3777 3778 3779 3780 3781 3782 3783 3784 3785 3786 3787 3788 3789 3790 3791 3792 3793 3794 3795 3796 3797 3798 3799 3800 3801 3802 3803 3804 3805 3806 3807
	if (ret) {
		ret = -EFAULT;
		goto out;
	}

out:
	btrfs_free_path(path);
	free_ipath(ipath);
	kfree(ipa);

	return ret;
}

static int build_ino_list(u64 inum, u64 offset, u64 root, void *ctx)
{
	struct btrfs_data_container *inodes = ctx;
	const size_t c = 3 * sizeof(u64);

	if (inodes->bytes_left >= c) {
		inodes->bytes_left -= c;
		inodes->val[inodes->elem_cnt] = inum;
		inodes->val[inodes->elem_cnt + 1] = offset;
		inodes->val[inodes->elem_cnt + 2] = root;
		inodes->elem_cnt += 3;
	} else {
		inodes->bytes_missing += c - inodes->bytes_left;
		inodes->bytes_left = 0;
		inodes->elem_missed += 3;
	}

	return 0;
}

static long btrfs_ioctl_logical_to_ino(struct btrfs_root *root,
					void __user *arg)
{
	int ret = 0;
	int size;
	struct btrfs_ioctl_logical_ino_args *loi;
	struct btrfs_data_container *inodes = NULL;
	struct btrfs_path *path = NULL;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	loi = memdup_user(arg, sizeof(*loi));
	if (IS_ERR(loi)) {
		ret = PTR_ERR(loi);
		loi = NULL;
		goto out;
	}

	path = btrfs_alloc_path();
	if (!path) {
		ret = -ENOMEM;
		goto out;
	}

3808
	size = min_t(u32, loi->size, 64 * 1024);
3809 3810 3811 3812 3813 3814 3815
	inodes = init_data_container(size);
	if (IS_ERR(inodes)) {
		ret = PTR_ERR(inodes);
		inodes = NULL;
		goto out;
	}

L
Liu Bo 已提交
3816 3817 3818
	ret = iterate_inodes_from_logical(loi->logical, root->fs_info, path,
					  build_ino_list, inodes);
	if (ret == -EINVAL)
3819 3820 3821 3822
		ret = -ENOENT;
	if (ret < 0)
		goto out;

3823 3824
	ret = copy_to_user((void *)(unsigned long)loi->inodes,
			   (void *)(unsigned long)inodes, size);
3825 3826 3827 3828 3829
	if (ret)
		ret = -EFAULT;

out:
	btrfs_free_path(path);
3830
	vfree(inodes);
3831 3832 3833 3834 3835
	kfree(loi);

	return ret;
}

3836
void update_ioctl_balance_args(struct btrfs_fs_info *fs_info, int lock,
3837 3838 3839 3840 3841 3842
			       struct btrfs_ioctl_balance_args *bargs)
{
	struct btrfs_balance_control *bctl = fs_info->balance_ctl;

	bargs->flags = bctl->flags;

3843 3844 3845 3846
	if (atomic_read(&fs_info->balance_running))
		bargs->state |= BTRFS_BALANCE_STATE_RUNNING;
	if (atomic_read(&fs_info->balance_pause_req))
		bargs->state |= BTRFS_BALANCE_STATE_PAUSE_REQ;
3847 3848
	if (atomic_read(&fs_info->balance_cancel_req))
		bargs->state |= BTRFS_BALANCE_STATE_CANCEL_REQ;
3849

3850 3851 3852
	memcpy(&bargs->data, &bctl->data, sizeof(bargs->data));
	memcpy(&bargs->meta, &bctl->meta, sizeof(bargs->meta));
	memcpy(&bargs->sys, &bctl->sys, sizeof(bargs->sys));
3853 3854 3855 3856 3857 3858 3859 3860

	if (lock) {
		spin_lock(&fs_info->balance_lock);
		memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
		spin_unlock(&fs_info->balance_lock);
	} else {
		memcpy(&bargs->stat, &bctl->stat, sizeof(bargs->stat));
	}
3861 3862
}

3863
static long btrfs_ioctl_balance(struct file *file, void __user *arg)
3864
{
A
Al Viro 已提交
3865
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
3866 3867 3868
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_ioctl_balance_args *bargs;
	struct btrfs_balance_control *bctl;
3869
	bool need_unlock; /* for mut. excl. ops lock */
3870 3871 3872 3873 3874
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

3875
	ret = mnt_want_write_file(file);
3876 3877 3878
	if (ret)
		return ret;

3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 3892
again:
	if (!atomic_xchg(&fs_info->mutually_exclusive_operation_running, 1)) {
		mutex_lock(&fs_info->volume_mutex);
		mutex_lock(&fs_info->balance_mutex);
		need_unlock = true;
		goto locked;
	}

	/*
	 * mut. excl. ops lock is locked.  Three possibilites:
	 *   (1) some other op is running
	 *   (2) balance is running
	 *   (3) balance is paused -- special case (think resume)
	 */
3893
	mutex_lock(&fs_info->balance_mutex);
3894 3895 3896 3897 3898 3899 3900 3901 3902 3903 3904 3905 3906 3907 3908 3909 3910 3911 3912 3913 3914 3915 3916 3917 3918 3919 3920 3921 3922 3923 3924 3925 3926 3927
	if (fs_info->balance_ctl) {
		/* this is either (2) or (3) */
		if (!atomic_read(&fs_info->balance_running)) {
			mutex_unlock(&fs_info->balance_mutex);
			if (!mutex_trylock(&fs_info->volume_mutex))
				goto again;
			mutex_lock(&fs_info->balance_mutex);

			if (fs_info->balance_ctl &&
			    !atomic_read(&fs_info->balance_running)) {
				/* this is (3) */
				need_unlock = false;
				goto locked;
			}

			mutex_unlock(&fs_info->balance_mutex);
			mutex_unlock(&fs_info->volume_mutex);
			goto again;
		} else {
			/* this is (2) */
			mutex_unlock(&fs_info->balance_mutex);
			ret = -EINPROGRESS;
			goto out;
		}
	} else {
		/* this is (1) */
		mutex_unlock(&fs_info->balance_mutex);
		pr_info("btrfs: dev add/delete/balance/replace/resize operation in progress\n");
		ret = -EINVAL;
		goto out;
	}

locked:
	BUG_ON(!atomic_read(&fs_info->mutually_exclusive_operation_running));
3928 3929 3930 3931 3932

	if (arg) {
		bargs = memdup_user(arg, sizeof(*bargs));
		if (IS_ERR(bargs)) {
			ret = PTR_ERR(bargs);
3933
			goto out_unlock;
3934
		}
3935 3936 3937 3938 3939 3940 3941 3942 3943 3944 3945 3946 3947 3948

		if (bargs->flags & BTRFS_BALANCE_RESUME) {
			if (!fs_info->balance_ctl) {
				ret = -ENOTCONN;
				goto out_bargs;
			}

			bctl = fs_info->balance_ctl;
			spin_lock(&fs_info->balance_lock);
			bctl->flags |= BTRFS_BALANCE_RESUME;
			spin_unlock(&fs_info->balance_lock);

			goto do_balance;
		}
3949 3950 3951 3952
	} else {
		bargs = NULL;
	}

3953
	if (fs_info->balance_ctl) {
3954 3955 3956 3957
		ret = -EINPROGRESS;
		goto out_bargs;
	}

3958 3959 3960 3961 3962 3963 3964 3965 3966 3967 3968 3969 3970
	bctl = kzalloc(sizeof(*bctl), GFP_NOFS);
	if (!bctl) {
		ret = -ENOMEM;
		goto out_bargs;
	}

	bctl->fs_info = fs_info;
	if (arg) {
		memcpy(&bctl->data, &bargs->data, sizeof(bctl->data));
		memcpy(&bctl->meta, &bargs->meta, sizeof(bctl->meta));
		memcpy(&bctl->sys, &bargs->sys, sizeof(bctl->sys));

		bctl->flags = bargs->flags;
3971 3972 3973
	} else {
		/* balance everything - no filters */
		bctl->flags |= BTRFS_BALANCE_TYPE_MASK;
3974 3975
	}

3976
do_balance:
3977
	/*
3978 3979 3980 3981 3982
	 * Ownership of bctl and mutually_exclusive_operation_running
	 * goes to to btrfs_balance.  bctl is freed in __cancel_balance,
	 * or, if restriper was paused all the way until unmount, in
	 * free_fs_info.  mutually_exclusive_operation_running is
	 * cleared in __cancel_balance.
3983
	 */
3984 3985 3986 3987
	need_unlock = false;

	ret = btrfs_balance(bctl, bargs);

3988 3989 3990 3991 3992 3993 3994
	if (arg) {
		if (copy_to_user(arg, bargs, sizeof(*bargs)))
			ret = -EFAULT;
	}

out_bargs:
	kfree(bargs);
3995
out_unlock:
3996 3997
	mutex_unlock(&fs_info->balance_mutex);
	mutex_unlock(&fs_info->volume_mutex);
3998 3999 4000
	if (need_unlock)
		atomic_set(&fs_info->mutually_exclusive_operation_running, 0);
out:
4001
	mnt_drop_write_file(file);
4002 4003 4004
	return ret;
}

4005 4006 4007 4008 4009 4010 4011 4012
static long btrfs_ioctl_balance_ctl(struct btrfs_root *root, int cmd)
{
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	switch (cmd) {
	case BTRFS_BALANCE_CTL_PAUSE:
		return btrfs_pause_balance(root->fs_info);
4013 4014
	case BTRFS_BALANCE_CTL_CANCEL:
		return btrfs_cancel_balance(root->fs_info);
4015 4016 4017 4018 4019
	}

	return -EINVAL;
}

4020 4021 4022 4023 4024 4025 4026 4027 4028 4029 4030 4031 4032 4033 4034 4035 4036 4037 4038 4039 4040 4041 4042 4043 4044 4045 4046 4047 4048 4049 4050 4051 4052
static long btrfs_ioctl_balance_progress(struct btrfs_root *root,
					 void __user *arg)
{
	struct btrfs_fs_info *fs_info = root->fs_info;
	struct btrfs_ioctl_balance_args *bargs;
	int ret = 0;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	mutex_lock(&fs_info->balance_mutex);
	if (!fs_info->balance_ctl) {
		ret = -ENOTCONN;
		goto out;
	}

	bargs = kzalloc(sizeof(*bargs), GFP_NOFS);
	if (!bargs) {
		ret = -ENOMEM;
		goto out;
	}

	update_ioctl_balance_args(fs_info, 1, bargs);

	if (copy_to_user(arg, bargs, sizeof(*bargs)))
		ret = -EFAULT;

	kfree(bargs);
out:
	mutex_unlock(&fs_info->balance_mutex);
	return ret;
}

4053
static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4054
{
A
Al Viro 已提交
4055
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4056 4057 4058 4059 4060 4061 4062 4063
	struct btrfs_ioctl_quota_ctl_args *sa;
	struct btrfs_trans_handle *trans = NULL;
	int ret;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4064 4065 4066
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4067 4068

	sa = memdup_user(arg, sizeof(*sa));
4069 4070 4071 4072
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4073

4074
	down_write(&root->fs_info->subvol_sem);
J
Jan Schmidt 已提交
4075 4076 4077 4078
	trans = btrfs_start_transaction(root->fs_info->tree_root, 2);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
A
Arne Jansen 已提交
4079 4080 4081 4082 4083 4084 4085 4086 4087 4088 4089 4090 4091 4092
	}

	switch (sa->cmd) {
	case BTRFS_QUOTA_CTL_ENABLE:
		ret = btrfs_quota_enable(trans, root->fs_info);
		break;
	case BTRFS_QUOTA_CTL_DISABLE:
		ret = btrfs_quota_disable(trans, root->fs_info);
		break;
	default:
		ret = -EINVAL;
		break;
	}

J
Jan Schmidt 已提交
4093 4094 4095
	err = btrfs_commit_transaction(trans, root->fs_info->tree_root);
	if (err && !ret)
		ret = err;
A
Arne Jansen 已提交
4096 4097
out:
	kfree(sa);
4098
	up_write(&root->fs_info->subvol_sem);
4099 4100
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4101 4102 4103
	return ret;
}

4104
static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4105
{
A
Al Viro 已提交
4106
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4107 4108 4109 4110 4111 4112 4113 4114
	struct btrfs_ioctl_qgroup_assign_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4115 4116 4117
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4118 4119

	sa = memdup_user(arg, sizeof(*sa));
4120 4121 4122 4123
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4124 4125 4126 4127 4128 4129 4130 4131 4132 4133 4134 4135 4136 4137 4138 4139 4140 4141 4142 4143 4144 4145

	trans = btrfs_join_transaction(root);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}

	/* FIXME: check if the IDs really exist */
	if (sa->assign) {
		ret = btrfs_add_qgroup_relation(trans, root->fs_info,
						sa->src, sa->dst);
	} else {
		ret = btrfs_del_qgroup_relation(trans, root->fs_info,
						sa->src, sa->dst);
	}

	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4146 4147
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4148 4149 4150
	return ret;
}

4151
static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4152
{
A
Al Viro 已提交
4153
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4154 4155 4156 4157 4158 4159 4160 4161
	struct btrfs_ioctl_qgroup_create_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4162 4163 4164
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4165 4166

	sa = memdup_user(arg, sizeof(*sa));
4167 4168 4169 4170
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4171

M
Miao Xie 已提交
4172 4173 4174 4175 4176
	if (!sa->qgroupid) {
		ret = -EINVAL;
		goto out;
	}

A
Arne Jansen 已提交
4177 4178 4179 4180 4181 4182 4183 4184 4185 4186 4187 4188 4189 4190 4191 4192 4193 4194 4195 4196
	trans = btrfs_join_transaction(root);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}

	/* FIXME: check if the IDs really exist */
	if (sa->create) {
		ret = btrfs_create_qgroup(trans, root->fs_info, sa->qgroupid,
					  NULL);
	} else {
		ret = btrfs_remove_qgroup(trans, root->fs_info, sa->qgroupid);
	}

	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4197 4198
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4199 4200 4201
	return ret;
}

4202
static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
A
Arne Jansen 已提交
4203
{
A
Al Viro 已提交
4204
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
A
Arne Jansen 已提交
4205 4206 4207 4208 4209 4210 4211 4212 4213
	struct btrfs_ioctl_qgroup_limit_args *sa;
	struct btrfs_trans_handle *trans;
	int ret;
	int err;
	u64 qgroupid;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

4214 4215 4216
	ret = mnt_want_write_file(file);
	if (ret)
		return ret;
A
Arne Jansen 已提交
4217 4218

	sa = memdup_user(arg, sizeof(*sa));
4219 4220 4221 4222
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		goto drop_write;
	}
A
Arne Jansen 已提交
4223 4224 4225 4226 4227 4228 4229 4230 4231 4232 4233 4234 4235 4236 4237 4238 4239 4240 4241 4242 4243 4244

	trans = btrfs_join_transaction(root);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out;
	}

	qgroupid = sa->qgroupid;
	if (!qgroupid) {
		/* take the current subvol as qgroup */
		qgroupid = root->root_key.objectid;
	}

	/* FIXME: check if the IDs really exist */
	ret = btrfs_limit_qgroup(trans, root->fs_info, qgroupid, &sa->lim);

	err = btrfs_end_transaction(trans, root);
	if (err && !ret)
		ret = err;

out:
	kfree(sa);
4245 4246
drop_write:
	mnt_drop_write_file(file);
A
Arne Jansen 已提交
4247 4248 4249
	return ret;
}

J
Jan Schmidt 已提交
4250 4251
static long btrfs_ioctl_quota_rescan(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4252
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4253 4254 4255 4256 4257 4258 4259 4260 4261 4262 4263 4264 4265 4266 4267 4268 4269 4270 4271 4272 4273 4274 4275 4276 4277 4278 4279 4280 4281 4282 4283 4284
	struct btrfs_ioctl_quota_rescan_args *qsa;
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	qsa = memdup_user(arg, sizeof(*qsa));
	if (IS_ERR(qsa)) {
		ret = PTR_ERR(qsa);
		goto drop_write;
	}

	if (qsa->flags) {
		ret = -EINVAL;
		goto out;
	}

	ret = btrfs_qgroup_rescan(root->fs_info);

out:
	kfree(qsa);
drop_write:
	mnt_drop_write_file(file);
	return ret;
}

static long btrfs_ioctl_quota_rescan_status(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4285
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
J
Jan Schmidt 已提交
4286 4287 4288 4289 4290 4291 4292 4293 4294 4295 4296 4297 4298 4299 4300 4301 4302 4303 4304 4305 4306 4307
	struct btrfs_ioctl_quota_rescan_args *qsa;
	int ret = 0;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	qsa = kzalloc(sizeof(*qsa), GFP_NOFS);
	if (!qsa)
		return -ENOMEM;

	if (root->fs_info->qgroup_flags & BTRFS_QGROUP_STATUS_FLAG_RESCAN) {
		qsa->flags = 1;
		qsa->progress = root->fs_info->qgroup_rescan_progress.objectid;
	}

	if (copy_to_user(arg, qsa, sizeof(*qsa)))
		ret = -EFAULT;

	kfree(qsa);
	return ret;
}

4308 4309 4310 4311 4312 4313 4314 4315 4316 4317
static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
{
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	return btrfs_qgroup_wait_for_completion(root->fs_info);
}

4318 4319 4320 4321
static long btrfs_ioctl_set_received_subvol(struct file *file,
					    void __user *arg)
{
	struct btrfs_ioctl_received_subvol_args *sa = NULL;
A
Al Viro 已提交
4322
	struct inode *inode = file_inode(file);
4323 4324 4325 4326 4327
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_root_item *root_item = &root->root_item;
	struct btrfs_trans_handle *trans;
	struct timespec ct = CURRENT_TIME;
	int ret = 0;
4328
	int received_uuid_changed;
4329 4330 4331 4332 4333 4334 4335 4336 4337 4338 4339 4340 4341 4342 4343 4344 4345 4346 4347 4348 4349 4350 4351 4352 4353 4354 4355 4356 4357

	ret = mnt_want_write_file(file);
	if (ret < 0)
		return ret;

	down_write(&root->fs_info->subvol_sem);

	if (btrfs_ino(inode) != BTRFS_FIRST_FREE_OBJECTID) {
		ret = -EINVAL;
		goto out;
	}

	if (btrfs_root_readonly(root)) {
		ret = -EROFS;
		goto out;
	}

	if (!inode_owner_or_capable(inode)) {
		ret = -EACCES;
		goto out;
	}

	sa = memdup_user(arg, sizeof(*sa));
	if (IS_ERR(sa)) {
		ret = PTR_ERR(sa);
		sa = NULL;
		goto out;
	}

4358 4359 4360 4361 4362
	/*
	 * 1 - root item
	 * 2 - uuid items (received uuid + subvol uuid)
	 */
	trans = btrfs_start_transaction(root, 3);
4363 4364 4365 4366 4367 4368 4369 4370 4371 4372
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		trans = NULL;
		goto out;
	}

	sa->rtransid = trans->transid;
	sa->rtime.sec = ct.tv_sec;
	sa->rtime.nsec = ct.tv_nsec;

4373 4374 4375 4376 4377 4378 4379 4380
	received_uuid_changed = memcmp(root_item->received_uuid, sa->uuid,
				       BTRFS_UUID_SIZE);
	if (received_uuid_changed &&
	    !btrfs_is_empty_uuid(root_item->received_uuid))
		btrfs_uuid_tree_rem(trans, root->fs_info->uuid_root,
				    root_item->received_uuid,
				    BTRFS_UUID_KEY_RECEIVED_SUBVOL,
				    root->root_key.objectid);
4381 4382 4383
	memcpy(root_item->received_uuid, sa->uuid, BTRFS_UUID_SIZE);
	btrfs_set_root_stransid(root_item, sa->stransid);
	btrfs_set_root_rtransid(root_item, sa->rtransid);
4384 4385 4386 4387
	btrfs_set_stack_timespec_sec(&root_item->stime, sa->stime.sec);
	btrfs_set_stack_timespec_nsec(&root_item->stime, sa->stime.nsec);
	btrfs_set_stack_timespec_sec(&root_item->rtime, sa->rtime.sec);
	btrfs_set_stack_timespec_nsec(&root_item->rtime, sa->rtime.nsec);
4388 4389 4390 4391 4392 4393

	ret = btrfs_update_root(trans, root->fs_info->tree_root,
				&root->root_key, &root->root_item);
	if (ret < 0) {
		btrfs_end_transaction(trans, root);
		goto out;
4394 4395 4396 4397 4398 4399 4400 4401
	}
	if (received_uuid_changed && !btrfs_is_empty_uuid(sa->uuid)) {
		ret = btrfs_uuid_tree_add(trans, root->fs_info->uuid_root,
					  sa->uuid,
					  BTRFS_UUID_KEY_RECEIVED_SUBVOL,
					  root->root_key.objectid);
		if (ret < 0 && ret != -EEXIST) {
			btrfs_abort_transaction(trans, root, ret);
4402
			goto out;
4403 4404 4405 4406 4407 4408
		}
	}
	ret = btrfs_commit_transaction(trans, root);
	if (ret < 0) {
		btrfs_abort_transaction(trans, root, ret);
		goto out;
4409 4410 4411 4412 4413 4414 4415 4416 4417 4418 4419 4420 4421
	}

	ret = copy_to_user(arg, sa, sizeof(*sa));
	if (ret)
		ret = -EFAULT;

out:
	kfree(sa);
	up_write(&root->fs_info->subvol_sem);
	mnt_drop_write_file(file);
	return ret;
}

4422 4423
static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4424
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4425
	size_t len;
4426
	int ret;
4427 4428 4429 4430 4431 4432 4433
	char label[BTRFS_LABEL_SIZE];

	spin_lock(&root->fs_info->super_lock);
	memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE);
	spin_unlock(&root->fs_info->super_lock);

	len = strnlen(label, BTRFS_LABEL_SIZE);
4434 4435 4436 4437 4438 4439 4440 4441 4442 4443 4444

	if (len == BTRFS_LABEL_SIZE) {
		pr_warn("btrfs: label is too long, return the first %zu bytes\n",
			--len);
	}

	ret = copy_to_user(arg, label, len);

	return ret ? -EFAULT : 0;
}

4445 4446
static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg)
{
A
Al Viro 已提交
4447
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4448 4449 4450 4451 4452 4453 4454 4455 4456 4457 4458 4459 4460 4461 4462 4463 4464 4465 4466 4467 4468 4469 4470 4471 4472 4473 4474
	struct btrfs_super_block *super_block = root->fs_info->super_copy;
	struct btrfs_trans_handle *trans;
	char label[BTRFS_LABEL_SIZE];
	int ret;

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	if (copy_from_user(label, arg, sizeof(label)))
		return -EFAULT;

	if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) {
		pr_err("btrfs: unable to set label with more than %d bytes\n",
		       BTRFS_LABEL_SIZE - 1);
		return -EINVAL;
	}

	ret = mnt_want_write_file(file);
	if (ret)
		return ret;

	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto out_unlock;
	}

4475
	spin_lock(&root->fs_info->super_lock);
4476
	strcpy(super_block->label, label);
4477
	spin_unlock(&root->fs_info->super_lock);
4478 4479 4480 4481 4482 4483 4484
	ret = btrfs_end_transaction(trans, root);

out_unlock:
	mnt_drop_write_file(file);
	return ret;
}

C
Christoph Hellwig 已提交
4485 4486 4487
long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
A
Al Viro 已提交
4488
	struct btrfs_root *root = BTRFS_I(file_inode(file))->root;
4489
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
4490 4491

	switch (cmd) {
4492 4493 4494 4495 4496 4497
	case FS_IOC_GETFLAGS:
		return btrfs_ioctl_getflags(file, argp);
	case FS_IOC_SETFLAGS:
		return btrfs_ioctl_setflags(file, argp);
	case FS_IOC_GETVERSION:
		return btrfs_ioctl_getversion(file, argp);
4498 4499
	case FITRIM:
		return btrfs_ioctl_fitrim(file, argp);
C
Christoph Hellwig 已提交
4500
	case BTRFS_IOC_SNAP_CREATE:
4501
		return btrfs_ioctl_snap_create(file, argp, 0);
4502
	case BTRFS_IOC_SNAP_CREATE_V2:
4503
		return btrfs_ioctl_snap_create_v2(file, argp, 0);
4504
	case BTRFS_IOC_SUBVOL_CREATE:
4505
		return btrfs_ioctl_snap_create(file, argp, 1);
A
Arne Jansen 已提交
4506 4507
	case BTRFS_IOC_SUBVOL_CREATE_V2:
		return btrfs_ioctl_snap_create_v2(file, argp, 1);
4508 4509
	case BTRFS_IOC_SNAP_DESTROY:
		return btrfs_ioctl_snap_destroy(file, argp);
4510 4511 4512 4513
	case BTRFS_IOC_SUBVOL_GETFLAGS:
		return btrfs_ioctl_subvol_getflags(file, argp);
	case BTRFS_IOC_SUBVOL_SETFLAGS:
		return btrfs_ioctl_subvol_setflags(file, argp);
4514 4515
	case BTRFS_IOC_DEFAULT_SUBVOL:
		return btrfs_ioctl_default_subvol(file, argp);
C
Christoph Hellwig 已提交
4516
	case BTRFS_IOC_DEFRAG:
C
Chris Mason 已提交
4517 4518 4519
		return btrfs_ioctl_defrag(file, NULL);
	case BTRFS_IOC_DEFRAG_RANGE:
		return btrfs_ioctl_defrag(file, argp);
C
Christoph Hellwig 已提交
4520
	case BTRFS_IOC_RESIZE:
4521
		return btrfs_ioctl_resize(file, argp);
C
Christoph Hellwig 已提交
4522
	case BTRFS_IOC_ADD_DEV:
4523
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
4524
	case BTRFS_IOC_RM_DEV:
4525
		return btrfs_ioctl_rm_dev(file, argp);
J
Jan Schmidt 已提交
4526 4527 4528 4529
	case BTRFS_IOC_FS_INFO:
		return btrfs_ioctl_fs_info(root, argp);
	case BTRFS_IOC_DEV_INFO:
		return btrfs_ioctl_dev_info(root, argp);
C
Christoph Hellwig 已提交
4530
	case BTRFS_IOC_BALANCE:
4531
		return btrfs_ioctl_balance(file, NULL);
C
Christoph Hellwig 已提交
4532
	case BTRFS_IOC_CLONE:
4533 4534
		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
	case BTRFS_IOC_CLONE_RANGE:
4535
		return btrfs_ioctl_clone_range(file, argp);
C
Christoph Hellwig 已提交
4536 4537 4538 4539
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
4540 4541 4542 4543
	case BTRFS_IOC_TREE_SEARCH:
		return btrfs_ioctl_tree_search(file, argp);
	case BTRFS_IOC_INO_LOOKUP:
		return btrfs_ioctl_ino_lookup(file, argp);
4544 4545 4546 4547
	case BTRFS_IOC_INO_PATHS:
		return btrfs_ioctl_ino_to_path(root, argp);
	case BTRFS_IOC_LOGICAL_INO:
		return btrfs_ioctl_logical_to_ino(root, argp);
J
Josef Bacik 已提交
4548 4549
	case BTRFS_IOC_SPACE_INFO:
		return btrfs_ioctl_space_info(root, argp);
C
Christoph Hellwig 已提交
4550 4551 4552
	case BTRFS_IOC_SYNC:
		btrfs_sync_fs(file->f_dentry->d_sb, 1);
		return 0;
4553
	case BTRFS_IOC_START_SYNC:
4554
		return btrfs_ioctl_start_sync(root, argp);
4555
	case BTRFS_IOC_WAIT_SYNC:
4556
		return btrfs_ioctl_wait_sync(root, argp);
J
Jan Schmidt 已提交
4557
	case BTRFS_IOC_SCRUB:
M
Miao Xie 已提交
4558
		return btrfs_ioctl_scrub(file, argp);
J
Jan Schmidt 已提交
4559 4560 4561 4562
	case BTRFS_IOC_SCRUB_CANCEL:
		return btrfs_ioctl_scrub_cancel(root, argp);
	case BTRFS_IOC_SCRUB_PROGRESS:
		return btrfs_ioctl_scrub_progress(root, argp);
4563
	case BTRFS_IOC_BALANCE_V2:
4564
		return btrfs_ioctl_balance(file, argp);
4565 4566
	case BTRFS_IOC_BALANCE_CTL:
		return btrfs_ioctl_balance_ctl(root, arg);
4567 4568
	case BTRFS_IOC_BALANCE_PROGRESS:
		return btrfs_ioctl_balance_progress(root, argp);
4569 4570
	case BTRFS_IOC_SET_RECEIVED_SUBVOL:
		return btrfs_ioctl_set_received_subvol(file, argp);
4571 4572
	case BTRFS_IOC_SEND:
		return btrfs_ioctl_send(file, argp);
4573
	case BTRFS_IOC_GET_DEV_STATS:
4574
		return btrfs_ioctl_get_dev_stats(root, argp);
A
Arne Jansen 已提交
4575
	case BTRFS_IOC_QUOTA_CTL:
4576
		return btrfs_ioctl_quota_ctl(file, argp);
A
Arne Jansen 已提交
4577
	case BTRFS_IOC_QGROUP_ASSIGN:
4578
		return btrfs_ioctl_qgroup_assign(file, argp);
A
Arne Jansen 已提交
4579
	case BTRFS_IOC_QGROUP_CREATE:
4580
		return btrfs_ioctl_qgroup_create(file, argp);
A
Arne Jansen 已提交
4581
	case BTRFS_IOC_QGROUP_LIMIT:
4582
		return btrfs_ioctl_qgroup_limit(file, argp);
J
Jan Schmidt 已提交
4583 4584 4585 4586
	case BTRFS_IOC_QUOTA_RESCAN:
		return btrfs_ioctl_quota_rescan(file, argp);
	case BTRFS_IOC_QUOTA_RESCAN_STATUS:
		return btrfs_ioctl_quota_rescan_status(file, argp);
4587 4588
	case BTRFS_IOC_QUOTA_RESCAN_WAIT:
		return btrfs_ioctl_quota_rescan_wait(file, argp);
4589 4590
	case BTRFS_IOC_DEV_REPLACE:
		return btrfs_ioctl_dev_replace(root, argp);
4591 4592
	case BTRFS_IOC_GET_FSLABEL:
		return btrfs_ioctl_get_fslabel(file, argp);
4593 4594
	case BTRFS_IOC_SET_FSLABEL:
		return btrfs_ioctl_set_fslabel(file, argp);
M
Mark Fasheh 已提交
4595 4596
	case BTRFS_IOC_FILE_EXTENT_SAME:
		return btrfs_ioctl_file_extent_same(file, argp);
C
Christoph Hellwig 已提交
4597 4598 4599 4600
	}

	return -ENOTTY;
}