ioctl.c 61.0 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 "compat.h"
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#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.h"
#include "ioctl.h"
#include "print-tree.h"
#include "volumes.h"
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#include "locking.h"
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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;

	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.
 *
 * Unlike extN we don't have any flags we don't want to inherit currently.
 */
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 (S_ISREG(inode->i_mode))
		flags &= ~BTRFS_INODE_DIRSYNC;
	else if (!S_ISDIR(inode->i_mode))
		flags &= (BTRFS_INODE_NODUMP | BTRFS_INODE_NOATIME);

	BTRFS_I(inode)->flags = flags;
	btrfs_update_iflags(inode);
}

static int btrfs_ioctl_getflags(struct file *file, void __user *arg)
{
	struct btrfs_inode *ip = BTRFS_I(file->f_path.dentry->d_inode);
	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 | \
		      FS_NOCOMP_FL | FS_COMPR_FL | \
		      FS_NOCOW_FL | FS_COW_FL))
		return -EOPNOTSUPP;

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

	if ((flags & FS_NOCOW_FL) && (flags & FS_COW_FL))
		return -EINVAL;

	return 0;
}

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static int btrfs_ioctl_setflags(struct file *file, void __user *arg)
{
	struct inode *inode = file->f_path.dentry->d_inode;
	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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	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 (!is_owner_or_cap(inode))
		return -EACCES;

	mutex_lock(&inode->i_mutex);

	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;
		}
	}

	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		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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	/*
	 * 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;
	}
	if (flags & FS_NOCOW_FL)
		ip->flags |= BTRFS_INODE_NODATACOW;
	else if (flags & FS_COW_FL)
		ip->flags &= ~BTRFS_INODE_NODATACOW;
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	trans = btrfs_join_transaction(root, 1);
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	BUG_ON(IS_ERR(trans));
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	ret = btrfs_update_inode(trans, root, inode);
	BUG_ON(ret);

	btrfs_update_iflags(inode);
	inode->i_ctime = CURRENT_TIME;
	btrfs_end_transaction(trans, root);

	mnt_drop_write(file->f_path.mnt);
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	ret = 0;
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 out_unlock:
	mutex_unlock(&inode->i_mutex);
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	return ret;
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}

static int btrfs_ioctl_getversion(struct file *file, int __user *arg)
{
	struct inode *inode = file->f_path.dentry->d_inode;

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

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

	mutex_lock(&fs_info->fs_devices->device_list_mutex);
	list_for_each_entry(device, &fs_info->fs_devices->devices, dev_list) {
		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);
		}
	}
	mutex_unlock(&fs_info->fs_devices->device_list_mutex);
	if (!num_devices)
		return -EOPNOTSUPP;

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

	range.minlen = max(range.minlen, minlen);
	ret = btrfs_trim_fs(root, &range);
	if (ret < 0)
		return ret;

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

	return 0;
}

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static noinline int create_subvol(struct btrfs_root *root,
				  struct dentry *dentry,
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				  char *name, int namelen,
				  u64 *async_transid)
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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;
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	struct btrfs_root *new_root;
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	struct dentry *parent = dget_parent(dentry);
	struct inode *dir;
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	int ret;
	int err;
	u64 objectid;
	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
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	u64 index = 0;
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	ret = btrfs_find_free_objectid(NULL, root->fs_info->tree_root,
				       0, &objectid);
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	if (ret) {
		dput(parent);
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		return ret;
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	}

	dir = parent->d_inode;

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	/*
	 * 1 - inode item
	 * 2 - refs
	 * 1 - root item
	 * 2 - dir items
	 */
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	trans = btrfs_start_transaction(root, 6);
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	if (IS_ERR(trans)) {
		dput(parent);
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		return PTR_ERR(trans);
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	}
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	leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
				      0, objectid, NULL, 0, 0, 0);
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	if (IS_ERR(leaf)) {
		ret = PTR_ERR(leaf);
		goto fail;
	}
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	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);

	write_extent_buffer(leaf, root->fs_info->fsid,
			    (unsigned long)btrfs_header_fsid(leaf),
			    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);

	inode_item = &root_item.inode;
	memset(inode_item, 0, sizeof(*inode_item));
	inode_item->generation = cpu_to_le64(1);
	inode_item->size = cpu_to_le64(3);
	inode_item->nlink = cpu_to_le32(1);
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	inode_item->nbytes = cpu_to_le64(root->leafsize);
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	inode_item->mode = cpu_to_le32(S_IFDIR | 0755);

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	root_item.flags = 0;
	root_item.byte_limit = 0;
	inode_item->flags = cpu_to_le64(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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	memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
	root_item.drop_level = 0;

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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);
	BUG_ON(IS_ERR(new_root));

	btrfs_record_root_in_trans(trans, new_root);

	ret = btrfs_create_subvol_root(trans, new_root, new_dirid,
				       BTRFS_I(dir)->block_group);
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	/*
	 * insert the directory item
	 */
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	ret = btrfs_set_inode_index(dir, &index);
	BUG_ON(ret);

	ret = btrfs_insert_dir_item(trans, root,
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				    name, namelen, dir->i_ino, &key,
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				    BTRFS_FT_DIR, index);
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	if (ret)
		goto fail;
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	btrfs_i_size_write(dir, dir->i_size + namelen * 2);
	ret = btrfs_update_inode(trans, root, dir);
	BUG_ON(ret);

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	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
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				 objectid, root->root_key.objectid,
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				 dir->i_ino, index, name, namelen);

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	BUG_ON(ret);
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	d_instantiate(dentry, btrfs_lookup_dentry(dir, dentry));
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fail:
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	dput(parent);
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	if (async_transid) {
		*async_transid = trans->transid;
		err = btrfs_commit_transaction_async(trans, root, 1);
	} else {
		err = btrfs_commit_transaction(trans, root);
	}
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	if (err && !ret)
		ret = err;
	return ret;
}

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static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
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			   char *name, int namelen, u64 *async_transid,
			   bool readonly)
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{
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	struct inode *inode;
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	struct dentry *parent;
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	struct btrfs_pending_snapshot *pending_snapshot;
	struct btrfs_trans_handle *trans;
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	int ret;
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	if (!root->ref_cows)
		return -EINVAL;

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

	btrfs_init_block_rsv(&pending_snapshot->block_rsv);
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	pending_snapshot->dentry = dentry;
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	pending_snapshot->root = root;
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	pending_snapshot->readonly = readonly;
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	trans = btrfs_start_transaction(root->fs_info->extent_root, 5);
	if (IS_ERR(trans)) {
		ret = PTR_ERR(trans);
		goto fail;
	}

	ret = btrfs_snap_reserve_metadata(trans, pending_snapshot);
	BUG_ON(ret);

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	list_add(&pending_snapshot->list,
		 &trans->transaction->pending_snapshots);
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	if (async_transid) {
		*async_transid = trans->transid;
		ret = btrfs_commit_transaction_async(trans,
				     root->fs_info->extent_root, 1);
	} else {
		ret = btrfs_commit_transaction(trans,
					       root->fs_info->extent_root);
	}
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	BUG_ON(ret);
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	ret = pending_snapshot->error;
	if (ret)
		goto fail;

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	ret = btrfs_orphan_cleanup(pending_snapshot->snap);
	if (ret)
		goto fail;
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	parent = dget_parent(dentry);
	inode = btrfs_lookup_dentry(parent->d_inode, dentry);
	dput(parent);
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	if (IS_ERR(inode)) {
		ret = PTR_ERR(inode);
		goto fail;
	}
	BUG_ON(!inode);
	d_instantiate(dentry, inode);
	ret = 0;
fail:
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	kfree(pending_snapshot);
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	return ret;
}

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/*  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)
{
	uid_t fsuid = current_fsuid();

	if (!(dir->i_mode & S_ISVTX))
		return 0;
	if (inode->i_uid == fsuid)
		return 0;
	if (dir->i_uid == fsuid)
		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);
	audit_inode_child(victim, dir);

	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;
}

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/* 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.
 */
599 600
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
S
Sage Weil 已提交
601
				   struct btrfs_root *snap_src,
L
Li Zefan 已提交
602
				   u64 *async_transid, bool readonly)
603
{
604
	struct inode *dir  = parent->dentry->d_inode;
605 606 607
	struct dentry *dentry;
	int error;

608
	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
609 610 611 612 613 614 615 616 617 618 619 620 621 622

	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;

	error = mnt_want_write(parent->mnt);
	if (error)
		goto out_dput;

623
	error = btrfs_may_create(dir, dentry);
624 625 626
	if (error)
		goto out_drop_write;

627 628 629 630 631
	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;

632
	if (snap_src) {
S
Sage Weil 已提交
633
		error = create_snapshot(snap_src, dentry,
L
Li Zefan 已提交
634
					name, namelen, async_transid, readonly);
635
	} else {
636
		error = create_subvol(BTRFS_I(dir)->root, dentry,
S
Sage Weil 已提交
637
				      name, namelen, async_transid);
638
	}
639 640 641 642
	if (!error)
		fsnotify_mkdir(dir, dentry);
out_up_read:
	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
643 644 645 646 647
out_drop_write:
	mnt_drop_write(parent->mnt);
out_dput:
	dput(dentry);
out_unlock:
648
	mutex_unlock(&dir->i_mutex);
649 650 651
	return error;
}

652
static int should_defrag_range(struct inode *inode, u64 start, u64 len,
C
Chris Mason 已提交
653 654
			       int thresh, u64 *last_len, u64 *skip,
			       u64 *defrag_end)
655 656 657 658 659 660
{
	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;
	int ret = 1;

C
Chris Mason 已提交
661 662 663 664

	if (thresh == 0)
		thresh = 256 * 1024;

665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687
	/*
	 * make sure that once we start defragging and extent, we keep on
	 * defragging it
	 */
	if (start < *defrag_end)
		return 1;

	*skip = 0;

	/*
	 * hopefully we have this extent in the tree already, try without
	 * the full extent lock
	 */
	read_lock(&em_tree->lock);
	em = lookup_extent_mapping(em_tree, start, len);
	read_unlock(&em_tree->lock);

	if (!em) {
		/* get the big lock and read metadata off disk */
		lock_extent(io_tree, start, start + len - 1, GFP_NOFS);
		em = btrfs_get_extent(inode, NULL, 0, start, len, 0);
		unlock_extent(io_tree, start, start + len - 1, GFP_NOFS);

688
		if (IS_ERR(em))
689 690 691 692 693 694 695 696 697 698
			return 0;
	}

	/* this will cover holes, and inline extents */
	if (em->block_start >= EXTENT_MAP_LAST_BYTE)
		ret = 0;

	/*
	 * we hit a real extent, if it is big don't bother defragging it again
	 */
C
Chris Mason 已提交
699
	if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722
		ret = 0;

	/*
	 * 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) {
		*last_len += len;
		*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
723 724
static int btrfs_defrag_file(struct file *file,
			     struct btrfs_ioctl_defrag_range_args *range)
C
Christoph Hellwig 已提交
725 726 727 728
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
729
	struct btrfs_ordered_extent *ordered;
C
Christoph Hellwig 已提交
730
	struct page *page;
731
	struct btrfs_super_block *disk_super;
C
Christoph Hellwig 已提交
732 733 734
	unsigned long last_index;
	unsigned long ra_pages = root->fs_info->bdi.ra_pages;
	unsigned long total_read = 0;
735
	u64 features;
C
Christoph Hellwig 已提交
736 737
	u64 page_start;
	u64 page_end;
738 739 740
	u64 last_len = 0;
	u64 skip = 0;
	u64 defrag_end = 0;
C
Christoph Hellwig 已提交
741 742
	unsigned long i;
	int ret;
743 744 745 746 747 748 749 750
	int compress_type = BTRFS_COMPRESS_ZLIB;

	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
751

752 753 754
	if (inode->i_size == 0)
		return 0;

C
Chris Mason 已提交
755 756 757 758 759 760 761 762
	if (range->start + range->len > range->start) {
		last_index = min_t(u64, inode->i_size - 1,
			 range->start + range->len - 1) >> PAGE_CACHE_SHIFT;
	} else {
		last_index = (inode->i_size - 1) >> PAGE_CACHE_SHIFT;
	}

	i = range->start >> PAGE_CACHE_SHIFT;
763 764
	while (i <= last_index) {
		if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
C
Chris Mason 已提交
765 766 767
					PAGE_CACHE_SIZE,
					range->extent_thresh,
					&last_len, &skip,
768 769 770 771 772 773 774 775 776 777
					&defrag_end)) {
			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;
		}
C
Christoph Hellwig 已提交
778 779 780 781 782 783

		if (total_read % ra_pages == 0) {
			btrfs_force_ra(inode->i_mapping, &file->f_ra, file, i,
				       min(last_index, i + ra_pages - 1));
		}
		total_read++;
784
		mutex_lock(&inode->i_mutex);
C
Chris Mason 已提交
785
		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
786
			BTRFS_I(inode)->force_compress = compress_type;
787

788 789 790
		ret  = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
		if (ret)
			goto err_unlock;
791
again:
792 793 794 795 796 797
		if (inode->i_size == 0 ||
		    i > ((inode->i_size - 1) >> PAGE_CACHE_SHIFT)) {
			ret = 0;
			goto err_reservations;
		}

C
Christoph Hellwig 已提交
798
		page = grab_cache_page(inode->i_mapping, i);
799 800
		if (!page) {
			ret = -ENOMEM;
801
			goto err_reservations;
802
		}
803

C
Christoph Hellwig 已提交
804 805 806 807 808 809
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
				page_cache_release(page);
810
				ret = -EIO;
811
				goto err_reservations;
C
Christoph Hellwig 已提交
812 813 814
			}
		}

815 816 817 818 819 820
		if (page->mapping != inode->i_mapping) {
			unlock_page(page);
			page_cache_release(page);
			goto again;
		}

C
Christoph Hellwig 已提交
821 822
		wait_on_page_writeback(page);

823
		if (PageDirty(page)) {
824
			btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
825 826 827
			goto loop_unlock;
		}

C
Christoph Hellwig 已提交
828 829 830
		page_start = (u64)page->index << PAGE_CACHE_SHIFT;
		page_end = page_start + PAGE_CACHE_SIZE - 1;
		lock_extent(io_tree, page_start, page_end, GFP_NOFS);
831 832 833 834 835 836 837 838 839 840 841 842

		ordered = btrfs_lookup_ordered_extent(inode, page_start);
		if (ordered) {
			unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
			unlock_page(page);
			page_cache_release(page);
			btrfs_start_ordered_extent(inode, ordered, 1);
			btrfs_put_ordered_extent(ordered);
			goto again;
		}
		set_page_extent_mapped(page);

843 844 845 846 847
		/*
		 * this makes sure page_mkwrite is called on the
		 * page if it is dirtied again later
		 */
		clear_page_dirty_for_io(page);
848 849 850
		clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start,
				  page_end, EXTENT_DIRTY | EXTENT_DELALLOC |
				  EXTENT_DO_ACCOUNTING, GFP_NOFS);
851

852
		btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
853
		ClearPageChecked(page);
C
Christoph Hellwig 已提交
854
		set_page_dirty(page);
C
Chris Mason 已提交
855
		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
856 857

loop_unlock:
C
Christoph Hellwig 已提交
858 859
		unlock_page(page);
		page_cache_release(page);
860 861
		mutex_unlock(&inode->i_mutex);

C
Christoph Hellwig 已提交
862
		balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
863
		i++;
C
Christoph Hellwig 已提交
864 865
	}

C
Chris Mason 已提交
866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883
	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);

		mutex_lock(&inode->i_mutex);
884
		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
C
Chris Mason 已提交
885 886 887
		mutex_unlock(&inode->i_mutex);
	}

888 889 890 891 892 893 894
	disk_super = &root->fs_info->super_copy;
	features = btrfs_super_incompat_flags(disk_super);
	if (range->compress_type == BTRFS_COMPRESS_LZO) {
		features |= BTRFS_FEATURE_INCOMPAT_COMPRESS_LZO;
		btrfs_set_super_incompat_flags(disk_super, features);
	}

C
Christoph Hellwig 已提交
895
	return 0;
896 897

err_reservations:
898 899
	btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
err_unlock:
900 901
	mutex_unlock(&inode->i_mutex);
	return ret;
C
Christoph Hellwig 已提交
902 903
}

904 905
static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
					void __user *arg)
C
Christoph Hellwig 已提交
906 907 908 909 910 911 912 913 914 915 916 917
{
	u64 new_size;
	u64 old_size;
	u64 devid = 1;
	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;

Y
Yan Zheng 已提交
918 919 920
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

921 922 923
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

L
Li Zefan 已提交
924 925 926
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
927 928

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
929

930
	mutex_lock(&root->fs_info->volume_mutex);
C
Christoph Hellwig 已提交
931 932 933 934 935 936 937 938
	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);
939 940
		printk(KERN_INFO "resizing devid %llu\n",
		       (unsigned long long)devid);
C
Christoph Hellwig 已提交
941
	}
Y
Yan Zheng 已提交
942
	device = btrfs_find_device(root, devid, NULL, NULL);
C
Christoph Hellwig 已提交
943
	if (!device) {
944 945
		printk(KERN_INFO "resizer unable to find device %llu\n",
		       (unsigned long long)devid);
C
Christoph Hellwig 已提交
946 947 948 949 950 951 952 953 954 955 956 957 958
		ret = -EINVAL;
		goto out_unlock;
	}
	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
959
		new_size = memparse(sizestr, NULL);
C
Christoph Hellwig 已提交
960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993
		if (new_size == 0) {
			ret = -EINVAL;
			goto out_unlock;
		}
	}

	old_size = device->total_bytes;

	if (mod < 0) {
		if (new_size > old_size) {
			ret = -EINVAL;
			goto out_unlock;
		}
		new_size = old_size - new_size;
	} else if (mod > 0) {
		new_size = old_size + new_size;
	}

	if (new_size < 256 * 1024 * 1024) {
		ret = -EINVAL;
		goto out_unlock;
	}
	if (new_size > device->bdev->bd_inode->i_size) {
		ret = -EFBIG;
		goto out_unlock;
	}

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

	printk(KERN_INFO "new size for %s is %llu\n",
		device->name, (unsigned long long)new_size);

	if (new_size > old_size) {
994
		trans = btrfs_start_transaction(root, 0);
995 996 997 998
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
			goto out_unlock;
		}
C
Christoph Hellwig 已提交
999 1000 1001 1002 1003 1004 1005
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
	} else {
		ret = btrfs_shrink_device(device, new_size);
	}

out_unlock:
1006
	mutex_unlock(&root->fs_info->volume_mutex);
C
Christoph Hellwig 已提交
1007 1008 1009 1010
	kfree(vol_args);
	return ret;
}

S
Sage Weil 已提交
1011 1012 1013 1014
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
						    char *name,
						    unsigned long fd,
						    int subvol,
L
Li Zefan 已提交
1015 1016
						    u64 *transid,
						    bool readonly)
C
Christoph Hellwig 已提交
1017
{
1018
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1019
	struct file *src_file;
C
Christoph Hellwig 已提交
1020
	int namelen;
1021
	int ret = 0;
C
Christoph Hellwig 已提交
1022

Y
Yan Zheng 已提交
1023 1024 1025
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

S
Sage Weil 已提交
1026 1027
	namelen = strlen(name);
	if (strchr(name, '/')) {
C
Christoph Hellwig 已提交
1028 1029 1030 1031
		ret = -EINVAL;
		goto out;
	}

1032
	if (subvol) {
S
Sage Weil 已提交
1033
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
L
Li Zefan 已提交
1034
				     NULL, transid, readonly);
1035
	} else {
1036
		struct inode *src_inode;
S
Sage Weil 已提交
1037
		src_file = fget(fd);
1038 1039 1040 1041 1042 1043 1044
		if (!src_file) {
			ret = -EINVAL;
			goto out;
		}

		src_inode = src_file->f_path.dentry->d_inode;
		if (src_inode->i_sb != file->f_path.dentry->d_inode->i_sb) {
C
Chris Mason 已提交
1045 1046
			printk(KERN_INFO "btrfs: Snapshot src from "
			       "another FS\n");
1047 1048 1049 1050
			ret = -EINVAL;
			fput(src_file);
			goto out;
		}
S
Sage Weil 已提交
1051 1052
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
				     BTRFS_I(src_inode)->root,
L
Li Zefan 已提交
1053
				     transid, readonly);
1054
		fput(src_file);
1055
	}
C
Christoph Hellwig 已提交
1056
out:
S
Sage Weil 已提交
1057 1058 1059 1060
	return ret;
}

static noinline int btrfs_ioctl_snap_create(struct file *file,
1061
					    void __user *arg, int subvol)
S
Sage Weil 已提交
1062
{
1063
	struct btrfs_ioctl_vol_args *vol_args;
S
Sage Weil 已提交
1064 1065
	int ret;

1066 1067 1068 1069
	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
1070

1071
	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1072 1073
					      vol_args->fd, subvol,
					      NULL, false);
1074

1075 1076 1077
	kfree(vol_args);
	return ret;
}
1078

1079 1080 1081 1082 1083 1084 1085
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
1086
	bool readonly = false;
1087

1088 1089 1090 1091
	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';
1092

L
Li Zefan 已提交
1093 1094 1095
	if (vol_args->flags &
	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
		ret = -EOPNOTSUPP;
1096
		goto out;
S
Sage Weil 已提交
1097
	}
1098 1099 1100

	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
		ptr = &transid;
L
Li Zefan 已提交
1101 1102
	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
		readonly = true;
1103 1104

	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1105 1106
					      vol_args->fd, subvol,
					      ptr, readonly);
1107 1108 1109 1110 1111 1112

	if (ret == 0 && ptr &&
	    copy_to_user(arg +
			 offsetof(struct btrfs_ioctl_vol_args_v2,
				  transid), ptr, sizeof(*ptr)))
		ret = -EFAULT;
1113
out:
C
Christoph Hellwig 已提交
1114 1115 1116 1117
	kfree(vol_args);
	return ret;
}

1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158
static noinline int btrfs_ioctl_subvol_getflags(struct file *file,
						void __user *arg)
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	int ret = 0;
	u64 flags = 0;

	if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID)
		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)
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
	u64 root_flags;
	u64 flags;
	int ret = 0;

	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

	if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID)
		return -EINVAL;

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

1159
	if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1160 1161 1162 1163 1164
		return -EINVAL;

	if (flags & ~BTRFS_SUBVOL_RDONLY)
		return -EOPNOTSUPP;

1165 1166 1167
	if (!is_owner_or_cap(inode))
		return -EACCES;

1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187
	down_write(&root->fs_info->subvol_sem);

	/* nothing to do */
	if (!!(flags & BTRFS_SUBVOL_RDONLY) == btrfs_root_readonly(root))
		goto out;

	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;
	}

1188
	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199
				&root->root_key, &root->root_item);

	btrfs_commit_transaction(trans, root);
out_reset:
	if (ret)
		btrfs_set_root_flags(&root->root_item, root_flags);
out:
	up_write(&root->fs_info->subvol_sem);
	return ret;
}

1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235
/*
 * helper to check if the subvolume references other subvolumes
 */
static noinline int may_destroy_subvol(struct btrfs_root *root)
{
	struct btrfs_path *path;
	struct btrfs_key key;
	int ret;

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

	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;
}

1236 1237 1238
static noinline int key_in_sk(struct btrfs_key *key,
			      struct btrfs_ioctl_search_key *sk)
{
1239 1240 1241 1242 1243 1244 1245 1246 1247
	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)
1248
		return 0;
1249 1250 1251 1252 1253 1254 1255

	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)
1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322
		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 found = 0;
	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);

		if (item_len > BTRFS_SEARCH_ARGS_BUFSIZE)
			item_len = 0;

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

		btrfs_item_key_to_cpu(leaf, key, i);
		if (!key_in_sk(key, sk))
			continue;

		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;
		}
1323
		found++;
1324 1325 1326 1327 1328

		if (*num_found >= sk->nr_items)
			break;
	}
advance_key:
1329 1330
	ret = 0;
	if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1331
		key->offset++;
1332 1333
	else if (key->type < (u8)-1 && key->type < sk->max_type) {
		key->offset = 0;
1334
		key->type++;
1335 1336 1337
	} else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
		key->offset = 0;
		key->type = 0;
1338
		key->objectid++;
1339 1340
	} else
		ret = 1;
1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420
overflow:
	*num_found += found;
	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) {
		ret = btrfs_search_forward(root, &key, &max_key, path, 0,
					   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);
		btrfs_release_path(root, path);
		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
1421 1422 1423
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
1424 1425 1426 1427 1428 1429 1430 1431 1432

	inode = fdentry(file)->d_inode;
	ret = search_ioctl(inode, args);
	if (ret == 0 && copy_to_user(argp, args, sizeof(*args)))
		ret = -EFAULT;
	kfree(args);
	return ret;
}

1433
/*
1434 1435 1436
 * Search INODE_REFs to identify path name of 'dirid' directory
 * in a 'tree_id' tree. and sets path name to 'name'.
 */
1437 1438 1439 1440 1441
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;
1442
	char *ptr;
1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459
	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;

1460
	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1461 1462 1463 1464 1465 1466 1467

	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);
1468 1469
		ret = -ENOENT;
		goto out;
1470 1471 1472 1473
	}

	key.objectid = dirid;
	key.type = BTRFS_INODE_REF_KEY;
1474
	key.offset = (u64)-1;
1475 1476 1477 1478 1479 1480 1481 1482

	while(1) {
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
		if (ret < 0)
			goto out;

		l = path->nodes[0];
		slot = path->slots[0];
1483 1484
		if (ret > 0 && slot > 0)
			slot--;
1485 1486 1487
		btrfs_item_key_to_cpu(l, &key, slot);

		if (ret > 0 && (key.objectid != dirid ||
1488 1489
				key.type != BTRFS_INODE_REF_KEY)) {
			ret = -ENOENT;
1490
			goto out;
1491
		}
1492 1493 1494 1495 1496

		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;
1497
		if (ptr < name)
1498 1499 1500 1501 1502 1503 1504 1505 1506 1507
			goto out;

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

		if (key.offset == BTRFS_FIRST_FREE_OBJECTID)
			break;

		btrfs_release_path(root, path);
		key.objectid = key.offset;
1508
		key.offset = (u64)-1;
1509 1510 1511
		dirid = key.objectid;

	}
1512
	if (ptr < name)
1513
		goto out;
1514
	memcpy(name, ptr, total_len);
1515 1516 1517 1518
	name[total_len]='\0';
	ret = 0;
out:
	btrfs_free_path(path);
1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531
	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
1532 1533 1534
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
1535

1536 1537
	inode = fdentry(file)->d_inode;

1538 1539 1540
	if (args->treeid == 0)
		args->treeid = BTRFS_I(inode)->root->root_key.objectid;

1541 1542 1543 1544 1545 1546 1547 1548
	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);
1549 1550 1551
	return ret;
}

1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595
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;
	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;
	}

	err = mnt_want_write(file->f_path.mnt);
	if (err)
		goto out;

	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
	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;
1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635
	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;

		/* check if subvolume may be deleted by a non-root user */
		err = btrfs_may_delete(dir, dentry, 1);
		if (err)
			goto out_dput;
	}

1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651
	if (inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
		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;

1652 1653 1654
	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		err = PTR_ERR(trans);
1655
		goto out_up_write;
1656 1657 1658
	}
	trans->block_rsv = &root->fs_info->global_block_rsv;

1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671
	ret = btrfs_unlink_subvol(trans, root, dir,
				dest->root_key.objectid,
				dentry->d_name.name,
				dentry->d_name.len);
	BUG_ON(ret);

	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);

1672 1673 1674 1675 1676 1677
	if (!xchg(&dest->orphan_item_inserted, 1)) {
		ret = btrfs_insert_orphan_item(trans,
					root->fs_info->tree_root,
					dest->root_key.objectid);
		BUG_ON(ret);
	}
1678

S
Sage Weil 已提交
1679
	ret = btrfs_end_transaction(trans, root);
1680 1681 1682 1683 1684 1685 1686
	BUG_ON(ret);
	inode->i_flags |= S_DEAD;
out_up_write:
	up_write(&root->fs_info->subvol_sem);
out_unlock:
	mutex_unlock(&inode->i_mutex);
	if (!err) {
1687
		shrink_dcache_sb(root->fs_info->sb);
1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700
		btrfs_invalidate_inodes(dest);
		d_delete(dentry);
	}
out_dput:
	dput(dentry);
out_unlock_dir:
	mutex_unlock(&dir->i_mutex);
	mnt_drop_write(file->f_path.mnt);
out:
	kfree(vol_args);
	return err;
}

C
Chris Mason 已提交
1701
static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
C
Christoph Hellwig 已提交
1702 1703 1704
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
C
Chris Mason 已提交
1705
	struct btrfs_ioctl_defrag_range_args *range;
Y
Yan Zheng 已提交
1706 1707
	int ret;

L
Li Zefan 已提交
1708 1709 1710
	if (btrfs_root_readonly(root))
		return -EROFS;

Y
Yan Zheng 已提交
1711 1712 1713
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		return ret;
C
Christoph Hellwig 已提交
1714 1715 1716

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
1717 1718 1719 1720
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
1721 1722 1723 1724
		ret = btrfs_defrag_root(root, 0);
		if (ret)
			goto out;
		ret = btrfs_defrag_root(root->fs_info->extent_root, 0);
C
Christoph Hellwig 已提交
1725 1726
		break;
	case S_IFREG:
1727 1728 1729 1730
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Chris Mason 已提交
1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742

		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);
1743
				goto out;
C
Chris Mason 已提交
1744 1745 1746 1747 1748 1749 1750 1751 1752 1753
			}
			/* 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;
		}
1754
		ret = btrfs_defrag_file(file, range);
C
Chris Mason 已提交
1755
		kfree(range);
C
Christoph Hellwig 已提交
1756
		break;
1757 1758
	default:
		ret = -EINVAL;
C
Christoph Hellwig 已提交
1759
	}
1760
out:
1761
	mnt_drop_write(file->f_path.mnt);
1762
	return ret;
C
Christoph Hellwig 已提交
1763 1764
}

1765
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
1766 1767 1768 1769
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

1770 1771 1772
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

L
Li Zefan 已提交
1773 1774 1775
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
1776

1777
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1778 1779 1780 1781 1782 1783
	ret = btrfs_init_new_device(root, vol_args->name);

	kfree(vol_args);
	return ret;
}

1784
static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
1785 1786 1787 1788
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

1789 1790 1791
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

Y
Yan Zheng 已提交
1792 1793 1794
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

L
Li Zefan 已提交
1795 1796 1797
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
1798

1799
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1800 1801 1802 1803 1804 1805
	ret = btrfs_rm_device(root, vol_args->name);

	kfree(vol_args);
	return ret;
}

1806 1807
static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
				       u64 off, u64 olen, u64 destoff)
C
Christoph Hellwig 已提交
1808 1809 1810 1811 1812 1813 1814 1815
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct file *src_file;
	struct inode *src;
	struct btrfs_trans_handle *trans;
	struct btrfs_path *path;
	struct extent_buffer *leaf;
Y
Yan Zheng 已提交
1816 1817
	char *buf;
	struct btrfs_key key;
C
Christoph Hellwig 已提交
1818 1819
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
1820
	int ret;
1821 1822 1823
	u64 len = olen;
	u64 bs = root->fs_info->sb->s_blocksize;
	u64 hint_byte;
1824

1825 1826 1827 1828 1829 1830 1831 1832 1833 1834
	/*
	 * 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)?
	 */

1835
	/* the destination must be opened for writing */
1836
	if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
1837 1838
		return -EINVAL;

L
Li Zefan 已提交
1839 1840 1841
	if (btrfs_root_readonly(root))
		return -EROFS;

Y
Yan Zheng 已提交
1842 1843 1844 1845
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		return ret;

1846
	src_file = fget(srcfd);
1847 1848 1849 1850
	if (!src_file) {
		ret = -EBADF;
		goto out_drop_write;
	}
1851

C
Christoph Hellwig 已提交
1852 1853
	src = src_file->f_dentry->d_inode;

1854 1855 1856 1857
	ret = -EINVAL;
	if (src == inode)
		goto out_fput;

1858 1859 1860 1861
	/* the src must be open for reading */
	if (!(src_file->f_mode & FMODE_READ))
		goto out_fput;

Y
Yan Zheng 已提交
1862 1863 1864 1865
	ret = -EISDIR;
	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
		goto out_fput;

C
Christoph Hellwig 已提交
1866
	ret = -EXDEV;
Y
Yan Zheng 已提交
1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877
	if (src->i_sb != inode->i_sb || BTRFS_I(src)->root != root)
		goto out_fput;

	ret = -ENOMEM;
	buf = vmalloc(btrfs_level_size(root, 0));
	if (!buf)
		goto out_fput;

	path = btrfs_alloc_path();
	if (!path) {
		vfree(buf);
C
Christoph Hellwig 已提交
1878
		goto out_fput;
Y
Yan Zheng 已提交
1879 1880
	}
	path->reada = 2;
C
Christoph Hellwig 已提交
1881 1882

	if (inode < src) {
1883 1884
		mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
		mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
C
Christoph Hellwig 已提交
1885
	} else {
1886 1887
		mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
		mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
C
Christoph Hellwig 已提交
1888 1889
	}

1890 1891
	/* determine range to clone */
	ret = -EINVAL;
1892
	if (off + len > src->i_size || off + len < off)
C
Christoph Hellwig 已提交
1893
		goto out_unlock;
1894 1895 1896 1897
	if (len == 0)
		olen = len = src->i_size - off;
	/* if we extend to eof, continue to block boundary */
	if (off + len == src->i_size)
1898
		len = ALIGN(src->i_size, bs) - off;
1899 1900

	/* verify the end result is block aligned */
1901 1902
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
	    !IS_ALIGNED(destoff, bs))
1903 1904
		goto out_unlock;

C
Christoph Hellwig 已提交
1905 1906 1907
	/* do any pending delalloc/csum calc on src, one way or
	   another, and lock file content */
	while (1) {
Z
Zheng Yan 已提交
1908
		struct btrfs_ordered_extent *ordered;
1909
		lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1910 1911 1912 1913
		ordered = btrfs_lookup_first_ordered_extent(src, off+len);
		if (!ordered &&
		    !test_range_bit(&BTRFS_I(src)->io_tree, off, off+len,
				   EXTENT_DELALLOC, 0, NULL))
C
Christoph Hellwig 已提交
1914
			break;
1915
		unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
Y
Yan Zheng 已提交
1916 1917
		if (ordered)
			btrfs_put_ordered_extent(ordered);
1918
		btrfs_wait_ordered_range(src, off, len);
C
Christoph Hellwig 已提交
1919 1920
	}

1921
	/* clone data */
C
Christoph Hellwig 已提交
1922
	key.objectid = src->i_ino;
Y
Yan Zheng 已提交
1923 1924
	key.type = BTRFS_EXTENT_DATA_KEY;
	key.offset = 0;
C
Christoph Hellwig 已提交
1925 1926 1927 1928 1929 1930

	while (1) {
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
1931
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
C
Christoph Hellwig 已提交
1932 1933 1934
		if (ret < 0)
			goto out;

Y
Yan Zheng 已提交
1935 1936
		nritems = btrfs_header_nritems(path->nodes[0]);
		if (path->slots[0] >= nritems) {
C
Christoph Hellwig 已提交
1937 1938 1939 1940 1941
			ret = btrfs_next_leaf(root, path);
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
1942
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
1943 1944 1945 1946
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
1947
		btrfs_item_key_to_cpu(leaf, &key, slot);
1948
		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
C
Christoph Hellwig 已提交
1949 1950 1951
		    key.objectid != src->i_ino)
			break;

1952 1953 1954
		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
1955 1956
			u32 size;
			struct btrfs_key new_key;
1957 1958 1959
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
1960
			u64 endoff;
Z
Zheng Yan 已提交
1961 1962 1963 1964 1965

			size = btrfs_item_size_nr(leaf, slot);
			read_extent_buffer(leaf, buf,
					   btrfs_item_ptr_offset(leaf, slot),
					   size);
1966 1967 1968 1969 1970

			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);
1971 1972
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
1973 1974 1975 1976
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
1977
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
1978 1979
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
1980 1981 1982 1983 1984
			} else if (type == BTRFS_FILE_EXTENT_INLINE) {
				/* take upper bound, may be compressed */
				datal = btrfs_file_extent_ram_bytes(leaf,
								    extent);
			}
Z
Zheng Yan 已提交
1985 1986
			btrfs_release_path(root, path);

1987
			if (key.offset + datal <= off ||
1988 1989 1990
			    key.offset >= off+len)
				goto next;

Z
Zheng Yan 已提交
1991 1992
			memcpy(&new_key, &key, sizeof(new_key));
			new_key.objectid = inode->i_ino;
1993 1994 1995 1996
			if (off <= key.offset)
				new_key.offset = key.offset + destoff - off;
			else
				new_key.offset = destoff;
Z
Zheng Yan 已提交
1997

1998 1999 2000 2001 2002 2003
			trans = btrfs_start_transaction(root, 1);
			if (IS_ERR(trans)) {
				ret = PTR_ERR(trans);
				goto out;
			}

2004 2005
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019
				if (off > key.offset) {
					datao += off - key.offset;
					datal -= off - key.offset;
				}

				if (key.offset + datal > off + len)
					datal = off + len - key.offset;

				ret = btrfs_drop_extents(trans, inode,
							 new_key.offset,
							 new_key.offset + datal,
							 &hint_byte, 1);
				BUG_ON(ret);

2020 2021
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
2022
				BUG_ON(ret);
2023 2024 2025 2026

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
2027 2028
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
2029

2030
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
2031
						struct btrfs_file_extent_item);
2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042

				/* 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
2043
					ret = btrfs_inc_extent_ref(trans, root,
2044 2045 2046 2047
							disko, diskl, 0,
							root->root_key.objectid,
							inode->i_ino,
							new_key.offset - datao);
Z
Zheng Yan 已提交
2048
					BUG_ON(ret);
C
Christoph Hellwig 已提交
2049
				}
2050 2051 2052 2053 2054 2055 2056
			} 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
2057

2058 2059
				if (key.offset + datal > off+len)
					trim = key.offset + datal - (off+len);
C
Chris Mason 已提交
2060

2061 2062
				if (comp && (skip || trim)) {
					ret = -EINVAL;
2063
					btrfs_end_transaction(trans, root);
2064 2065 2066 2067
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
2068 2069 2070 2071 2072 2073 2074

				ret = btrfs_drop_extents(trans, inode,
							 new_key.offset,
							 new_key.offset + datal,
							 &hint_byte, 1);
				BUG_ON(ret);

2075 2076
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
2077
				BUG_ON(ret);
2078 2079

				if (skip) {
C
Chris Mason 已提交
2080 2081
					u32 start =
					  btrfs_file_extent_calc_inline_size(0);
2082 2083 2084 2085 2086 2087 2088 2089 2090 2091
					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
2092
			}
2093 2094

			btrfs_mark_buffer_dirty(leaf);
2095
			btrfs_release_path(root, path);
2096

2097
			inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2098 2099 2100 2101 2102 2103 2104

			/*
			 * 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;
2105 2106
			if (endoff > destoff+olen)
				endoff = destoff+olen;
2107 2108 2109
			if (endoff > inode->i_size)
				btrfs_i_size_write(inode, endoff);

2110 2111 2112 2113 2114
			BTRFS_I(inode)->flags = BTRFS_I(src)->flags;
			ret = btrfs_update_inode(trans, root, inode);
			BUG_ON(ret);
			btrfs_end_transaction(trans, root);
		}
C
Chris Mason 已提交
2115
next:
Z
Zheng Yan 已提交
2116
		btrfs_release_path(root, path);
C
Christoph Hellwig 已提交
2117 2118 2119 2120
		key.offset++;
	}
	ret = 0;
out:
Y
Yan Zheng 已提交
2121
	btrfs_release_path(root, path);
2122
	unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
C
Christoph Hellwig 已提交
2123 2124 2125
out_unlock:
	mutex_unlock(&src->i_mutex);
	mutex_unlock(&inode->i_mutex);
Y
Yan Zheng 已提交
2126 2127
	vfree(buf);
	btrfs_free_path(path);
C
Christoph Hellwig 已提交
2128 2129
out_fput:
	fput(src_file);
2130 2131
out_drop_write:
	mnt_drop_write(file->f_path.mnt);
C
Christoph Hellwig 已提交
2132 2133 2134
	return ret;
}

2135
static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2136 2137 2138
{
	struct btrfs_ioctl_clone_range_args args;

2139
	if (copy_from_user(&args, argp, sizeof(args)))
2140 2141 2142 2143 2144
		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
2145 2146 2147 2148 2149 2150
/*
 * 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.
 */
2151
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
2152 2153 2154 2155
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
2156
	int ret;
C
Christoph Hellwig 已提交
2157

2158
	ret = -EPERM;
2159
	if (!capable(CAP_SYS_ADMIN))
2160
		goto out;
2161

2162 2163
	ret = -EINPROGRESS;
	if (file->private_data)
C
Christoph Hellwig 已提交
2164
		goto out;
2165

L
Li Zefan 已提交
2166 2167 2168 2169
	ret = -EROFS;
	if (btrfs_root_readonly(root))
		goto out;

Y
Yan Zheng 已提交
2170 2171 2172 2173
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		goto out;

2174 2175 2176 2177
	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans++;
	mutex_unlock(&root->fs_info->trans_mutex);

2178
	ret = -ENOMEM;
2179
	trans = btrfs_start_ioctl_transaction(root, 0);
2180
	if (IS_ERR(trans))
2181 2182 2183 2184 2185 2186 2187 2188 2189 2190
		goto out_drop;

	file->private_data = trans;
	return 0;

out_drop:
	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans--;
	mutex_unlock(&root->fs_info->trans_mutex);
	mnt_drop_write(file->f_path.mnt);
C
Christoph Hellwig 已提交
2191 2192 2193 2194
out:
	return ret;
}

2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235
static long btrfs_ioctl_default_subvol(struct file *file, void __user *argp)
{
	struct inode *inode = fdentry(file)->d_inode;
	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;
	struct btrfs_super_block *disk_super;
	u64 features;
	u64 objectid = 0;
	u64 dir_id;

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

	if (copy_from_user(&objectid, argp, sizeof(objectid)))
		return -EFAULT;

	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);
	if (IS_ERR(new_root))
		return PTR_ERR(new_root);

	if (btrfs_root_refs(&new_root->root_item) == 0)
		return -ENOENT;

	path = btrfs_alloc_path();
	if (!path)
		return -ENOMEM;
	path->leave_spinning = 1;

	trans = btrfs_start_transaction(root, 1);
2236
	if (IS_ERR(trans)) {
2237
		btrfs_free_path(path);
2238
		return PTR_ERR(trans);
2239 2240 2241 2242 2243
	}

	dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
	di = btrfs_lookup_dir_item(trans, root->fs_info->tree_root, path,
				   dir_id, "default", 7, 1);
2244
	if (IS_ERR_OR_NULL(di)) {
2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267
		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");
		return -ENOENT;
	}

	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);

	disk_super = &root->fs_info->super_copy;
	features = btrfs_super_incompat_flags(disk_super);
	if (!(features & BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL)) {
		features |= BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL;
		btrfs_set_super_incompat_flags(disk_super, features);
	}
	btrfs_end_transaction(trans, root);

	return 0;
}

2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283
static void get_block_group_info(struct list_head *groups_list,
				 struct btrfs_ioctl_space_info *space)
{
	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);
	}
}

J
Josef Bacik 已提交
2284 2285 2286 2287 2288
long btrfs_ioctl_space_info(struct btrfs_root *root, void __user *arg)
{
	struct btrfs_ioctl_space_args space_args;
	struct btrfs_ioctl_space_info space;
	struct btrfs_ioctl_space_info *dest;
2289
	struct btrfs_ioctl_space_info *dest_orig;
2290
	struct btrfs_ioctl_space_info __user *user_dest;
J
Josef Bacik 已提交
2291
	struct btrfs_space_info *info;
2292 2293 2294 2295 2296
	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;
2297
	int alloc_size;
J
Josef Bacik 已提交
2298
	int ret = 0;
2299
	u64 slot_count = 0;
2300
	int i, c;
J
Josef Bacik 已提交
2301 2302 2303 2304 2305 2306

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

2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330
	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);
	}
2331 2332 2333 2334 2335 2336

	/* space_slots == 0 means they are asking for a count */
	if (space_args.space_slots == 0) {
		space_args.total_spaces = slot_count;
		goto out;
	}
2337

2338
	slot_count = min_t(u64, space_args.space_slots, slot_count);
2339

2340
	alloc_size = sizeof(*dest) * slot_count;
2341

2342 2343 2344 2345 2346 2347
	/* 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
2348
	space_args.total_spaces = 0;
2349 2350 2351 2352
	dest = kmalloc(alloc_size, GFP_NOFS);
	if (!dest)
		return -ENOMEM;
	dest_orig = dest;
J
Josef Bacik 已提交
2353

2354
	/* now we have a buffer to copy into */
2355 2356 2357
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

2358 2359 2360
		if (!slot_count)
			break;

2361 2362 2363 2364 2365 2366 2367 2368 2369 2370
		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();
2371

2372 2373 2374 2375 2376 2377 2378 2379 2380 2381
		if (!info)
			continue;
		down_read(&info->groups_sem);
		for (c = 0; c < BTRFS_NR_RAID_TYPES; c++) {
			if (!list_empty(&info->block_groups[c])) {
				get_block_group_info(&info->block_groups[c],
						     &space);
				memcpy(dest, &space, sizeof(space));
				dest++;
				space_args.total_spaces++;
2382
				slot_count--;
2383
			}
2384 2385
			if (!slot_count)
				break;
2386 2387
		}
		up_read(&info->groups_sem);
J
Josef Bacik 已提交
2388 2389
	}

2390 2391 2392 2393 2394 2395 2396 2397 2398
	user_dest = (struct btrfs_ioctl_space_info *)
		(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
2399 2400 2401 2402 2403
		ret = -EFAULT;

	return ret;
}

C
Christoph Hellwig 已提交
2404 2405 2406 2407 2408 2409 2410 2411 2412 2413 2414 2415 2416
/*
 * 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)
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;

	trans = file->private_data;
2417 2418
	if (!trans)
		return -EINVAL;
C
Christoph Hellwig 已提交
2419
	file->private_data = NULL;
2420

2421 2422
	btrfs_end_transaction(trans, root);

2423 2424 2425 2426
	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans--;
	mutex_unlock(&root->fs_info->trans_mutex);

2427
	mnt_drop_write(file->f_path.mnt);
2428
	return 0;
C
Christoph Hellwig 已提交
2429 2430
}

2431 2432 2433 2434 2435
static noinline long btrfs_ioctl_start_sync(struct file *file, void __user *argp)
{
	struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
	struct btrfs_trans_handle *trans;
	u64 transid;
T
Tsutomu Itoh 已提交
2436
	int ret;
2437 2438

	trans = btrfs_start_transaction(root, 0);
2439 2440
	if (IS_ERR(trans))
		return PTR_ERR(trans);
2441
	transid = trans->transid;
T
Tsutomu Itoh 已提交
2442
	ret = btrfs_commit_transaction_async(trans, root, 0);
2443 2444
	if (ret) {
		btrfs_end_transaction(trans, root);
T
Tsutomu Itoh 已提交
2445
		return ret;
2446
	}
2447 2448 2449 2450 2451 2452 2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467

	if (argp)
		if (copy_to_user(argp, &transid, sizeof(transid)))
			return -EFAULT;
	return 0;
}

static noinline long btrfs_ioctl_wait_sync(struct file *file, void __user *argp)
{
	struct btrfs_root *root = BTRFS_I(file->f_dentry->d_inode)->root;
	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);
}

C
Christoph Hellwig 已提交
2468 2469 2470 2471
long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2472
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
2473 2474

	switch (cmd) {
2475 2476 2477 2478 2479 2480
	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);
2481 2482
	case FITRIM:
		return btrfs_ioctl_fitrim(file, argp);
C
Christoph Hellwig 已提交
2483
	case BTRFS_IOC_SNAP_CREATE:
2484
		return btrfs_ioctl_snap_create(file, argp, 0);
2485
	case BTRFS_IOC_SNAP_CREATE_V2:
2486
		return btrfs_ioctl_snap_create_v2(file, argp, 0);
2487
	case BTRFS_IOC_SUBVOL_CREATE:
2488
		return btrfs_ioctl_snap_create(file, argp, 1);
2489 2490
	case BTRFS_IOC_SNAP_DESTROY:
		return btrfs_ioctl_snap_destroy(file, argp);
2491 2492 2493 2494
	case BTRFS_IOC_SUBVOL_GETFLAGS:
		return btrfs_ioctl_subvol_getflags(file, argp);
	case BTRFS_IOC_SUBVOL_SETFLAGS:
		return btrfs_ioctl_subvol_setflags(file, argp);
2495 2496
	case BTRFS_IOC_DEFAULT_SUBVOL:
		return btrfs_ioctl_default_subvol(file, argp);
C
Christoph Hellwig 已提交
2497
	case BTRFS_IOC_DEFRAG:
C
Chris Mason 已提交
2498 2499 2500
		return btrfs_ioctl_defrag(file, NULL);
	case BTRFS_IOC_DEFRAG_RANGE:
		return btrfs_ioctl_defrag(file, argp);
C
Christoph Hellwig 已提交
2501
	case BTRFS_IOC_RESIZE:
2502
		return btrfs_ioctl_resize(root, argp);
C
Christoph Hellwig 已提交
2503
	case BTRFS_IOC_ADD_DEV:
2504
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
2505
	case BTRFS_IOC_RM_DEV:
2506
		return btrfs_ioctl_rm_dev(root, argp);
C
Christoph Hellwig 已提交
2507 2508 2509
	case BTRFS_IOC_BALANCE:
		return btrfs_balance(root->fs_info->dev_root);
	case BTRFS_IOC_CLONE:
2510 2511
		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
	case BTRFS_IOC_CLONE_RANGE:
2512
		return btrfs_ioctl_clone_range(file, argp);
C
Christoph Hellwig 已提交
2513 2514 2515 2516
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
2517 2518 2519 2520
	case BTRFS_IOC_TREE_SEARCH:
		return btrfs_ioctl_tree_search(file, argp);
	case BTRFS_IOC_INO_LOOKUP:
		return btrfs_ioctl_ino_lookup(file, argp);
J
Josef Bacik 已提交
2521 2522
	case BTRFS_IOC_SPACE_INFO:
		return btrfs_ioctl_space_info(root, argp);
C
Christoph Hellwig 已提交
2523 2524 2525
	case BTRFS_IOC_SYNC:
		btrfs_sync_fs(file->f_dentry->d_sb, 1);
		return 0;
2526 2527 2528 2529
	case BTRFS_IOC_START_SYNC:
		return btrfs_ioctl_start_sync(file, argp);
	case BTRFS_IOC_WAIT_SYNC:
		return btrfs_ioctl_wait_sync(file, argp);
C
Christoph Hellwig 已提交
2530 2531 2532 2533
	}

	return -ENOTTY;
}