ioctl.c 61.2 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;
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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.
 *
 * 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 | \
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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)
{
	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 (!inode_owner_or_capable(inode))
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		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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	if (flags & FS_NOCOW_FL)
		ip->flags |= BTRFS_INODE_NODATACOW;
	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_join_transaction(root);
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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;
}

590 591 592 593 594 595 596 597 598 599 600 601 602 603 604
/* 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.
 */
605 606
static noinline int btrfs_mksubvol(struct path *parent,
				   char *name, int namelen,
S
Sage Weil 已提交
607
				   struct btrfs_root *snap_src,
L
Li Zefan 已提交
608
				   u64 *async_transid, bool readonly)
609
{
610
	struct inode *dir  = parent->dentry->d_inode;
611 612 613
	struct dentry *dentry;
	int error;

614
	mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
615 616 617 618 619 620 621 622 623 624 625 626 627 628

	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;

629
	error = btrfs_may_create(dir, dentry);
630 631 632
	if (error)
		goto out_drop_write;

633 634 635 636 637
	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;

638
	if (snap_src) {
S
Sage Weil 已提交
639
		error = create_snapshot(snap_src, dentry,
L
Li Zefan 已提交
640
					name, namelen, async_transid, readonly);
641
	} else {
642
		error = create_subvol(BTRFS_I(dir)->root, dentry,
S
Sage Weil 已提交
643
				      name, namelen, async_transid);
644
	}
645 646 647 648
	if (!error)
		fsnotify_mkdir(dir, dentry);
out_up_read:
	up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
649 650 651 652 653
out_drop_write:
	mnt_drop_write(parent->mnt);
out_dput:
	dput(dentry);
out_unlock:
654
	mutex_unlock(&dir->i_mutex);
655 656 657
	return error;
}

658
static int should_defrag_range(struct inode *inode, u64 start, u64 len,
C
Chris Mason 已提交
659 660
			       int thresh, u64 *last_len, u64 *skip,
			       u64 *defrag_end)
661 662 663 664 665 666
{
	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
667 668 669 670

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

671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693
	/*
	 * 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);

694
		if (IS_ERR(em))
695 696 697 698 699 700 701 702 703 704
			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
705
	if ((*last_len == 0 || *last_len >= thresh) && em->len >= thresh)
706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728
		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
729 730
static int btrfs_defrag_file(struct file *file,
			     struct btrfs_ioctl_defrag_range_args *range)
C
Christoph Hellwig 已提交
731 732 733 734
{
	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;
735
	struct btrfs_ordered_extent *ordered;
C
Christoph Hellwig 已提交
736
	struct page *page;
737
	struct btrfs_super_block *disk_super;
C
Christoph Hellwig 已提交
738 739 740
	unsigned long last_index;
	unsigned long ra_pages = root->fs_info->bdi.ra_pages;
	unsigned long total_read = 0;
741
	u64 features;
C
Christoph Hellwig 已提交
742 743
	u64 page_start;
	u64 page_end;
744 745 746
	u64 last_len = 0;
	u64 skip = 0;
	u64 defrag_end = 0;
C
Christoph Hellwig 已提交
747 748
	unsigned long i;
	int ret;
749 750 751 752 753 754 755 756
	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
757

758 759 760
	if (inode->i_size == 0)
		return 0;

C
Chris Mason 已提交
761 762 763 764 765 766 767 768
	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;
769 770
	while (i <= last_index) {
		if (!should_defrag_range(inode, (u64)i << PAGE_CACHE_SHIFT,
C
Chris Mason 已提交
771 772 773
					PAGE_CACHE_SIZE,
					range->extent_thresh,
					&last_len, &skip,
774 775 776 777 778 779 780 781 782 783
					&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
784 785 786 787 788 789

		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++;
790
		mutex_lock(&inode->i_mutex);
C
Chris Mason 已提交
791
		if (range->flags & BTRFS_DEFRAG_RANGE_COMPRESS)
792
			BTRFS_I(inode)->force_compress = compress_type;
793

794 795 796
		ret  = btrfs_delalloc_reserve_space(inode, PAGE_CACHE_SIZE);
		if (ret)
			goto err_unlock;
797
again:
798 799 800 801 802 803
		if (inode->i_size == 0 ||
		    i > ((inode->i_size - 1) >> PAGE_CACHE_SHIFT)) {
			ret = 0;
			goto err_reservations;
		}

C
Christoph Hellwig 已提交
804
		page = grab_cache_page(inode->i_mapping, i);
805 806
		if (!page) {
			ret = -ENOMEM;
807
			goto err_reservations;
808
		}
809

C
Christoph Hellwig 已提交
810 811 812 813 814 815
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
				page_cache_release(page);
816
				ret = -EIO;
817
				goto err_reservations;
C
Christoph Hellwig 已提交
818 819 820
			}
		}

821 822 823 824 825 826
		if (page->mapping != inode->i_mapping) {
			unlock_page(page);
			page_cache_release(page);
			goto again;
		}

C
Christoph Hellwig 已提交
827 828
		wait_on_page_writeback(page);

829
		if (PageDirty(page)) {
830
			btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
831 832 833
			goto loop_unlock;
		}

C
Christoph Hellwig 已提交
834 835 836
		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);
837 838 839 840 841 842 843 844 845 846 847 848

		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);

849 850 851 852 853
		/*
		 * this makes sure page_mkwrite is called on the
		 * page if it is dirtied again later
		 */
		clear_page_dirty_for_io(page);
854 855 856
		clear_extent_bits(&BTRFS_I(inode)->io_tree, page_start,
				  page_end, EXTENT_DIRTY | EXTENT_DELALLOC |
				  EXTENT_DO_ACCOUNTING, GFP_NOFS);
857

858
		btrfs_set_extent_delalloc(inode, page_start, page_end, NULL);
859
		ClearPageChecked(page);
C
Christoph Hellwig 已提交
860
		set_page_dirty(page);
C
Chris Mason 已提交
861
		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
862 863

loop_unlock:
C
Christoph Hellwig 已提交
864 865
		unlock_page(page);
		page_cache_release(page);
866 867
		mutex_unlock(&inode->i_mutex);

C
Christoph Hellwig 已提交
868
		balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
869
		i++;
C
Christoph Hellwig 已提交
870 871
	}

C
Chris Mason 已提交
872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889
	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);
890
		BTRFS_I(inode)->force_compress = BTRFS_COMPRESS_NONE;
C
Chris Mason 已提交
891 892 893
		mutex_unlock(&inode->i_mutex);
	}

894 895 896 897 898 899 900
	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
901
	return 0;
902 903

err_reservations:
904 905
	btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
err_unlock:
906 907
	mutex_unlock(&inode->i_mutex);
	return ret;
C
Christoph Hellwig 已提交
908 909
}

910 911
static noinline int btrfs_ioctl_resize(struct btrfs_root *root,
					void __user *arg)
C
Christoph Hellwig 已提交
912 913 914 915 916 917 918 919 920 921 922 923
{
	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
924 925 926
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

927 928 929
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

L
Li Zefan 已提交
930 931 932
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
933 934

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
935

936
	mutex_lock(&root->fs_info->volume_mutex);
C
Christoph Hellwig 已提交
937 938 939 940 941 942 943 944
	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);
945 946
		printk(KERN_INFO "resizing devid %llu\n",
		       (unsigned long long)devid);
C
Christoph Hellwig 已提交
947
	}
Y
Yan Zheng 已提交
948
	device = btrfs_find_device(root, devid, NULL, NULL);
C
Christoph Hellwig 已提交
949
	if (!device) {
950 951
		printk(KERN_INFO "resizer unable to find device %llu\n",
		       (unsigned long long)devid);
C
Christoph Hellwig 已提交
952 953 954 955 956 957 958 959 960 961 962 963 964
		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
965
		new_size = memparse(sizestr, NULL);
C
Christoph Hellwig 已提交
966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999
		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) {
1000
		trans = btrfs_start_transaction(root, 0);
1001 1002 1003 1004
		if (IS_ERR(trans)) {
			ret = PTR_ERR(trans);
			goto out_unlock;
		}
C
Christoph Hellwig 已提交
1005 1006 1007 1008 1009 1010 1011
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
	} else {
		ret = btrfs_shrink_device(device, new_size);
	}

out_unlock:
1012
	mutex_unlock(&root->fs_info->volume_mutex);
C
Christoph Hellwig 已提交
1013 1014 1015 1016
	kfree(vol_args);
	return ret;
}

S
Sage Weil 已提交
1017 1018 1019 1020
static noinline int btrfs_ioctl_snap_create_transid(struct file *file,
						    char *name,
						    unsigned long fd,
						    int subvol,
L
Li Zefan 已提交
1021 1022
						    u64 *transid,
						    bool readonly)
C
Christoph Hellwig 已提交
1023
{
1024
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1025
	struct file *src_file;
C
Christoph Hellwig 已提交
1026
	int namelen;
1027
	int ret = 0;
C
Christoph Hellwig 已提交
1028

Y
Yan Zheng 已提交
1029 1030 1031
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

S
Sage Weil 已提交
1032 1033
	namelen = strlen(name);
	if (strchr(name, '/')) {
C
Christoph Hellwig 已提交
1034 1035 1036 1037
		ret = -EINVAL;
		goto out;
	}

1038
	if (subvol) {
S
Sage Weil 已提交
1039
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
L
Li Zefan 已提交
1040
				     NULL, transid, readonly);
1041
	} else {
1042
		struct inode *src_inode;
S
Sage Weil 已提交
1043
		src_file = fget(fd);
1044 1045 1046 1047 1048 1049 1050
		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
1051 1052
			printk(KERN_INFO "btrfs: Snapshot src from "
			       "another FS\n");
1053 1054 1055 1056
			ret = -EINVAL;
			fput(src_file);
			goto out;
		}
S
Sage Weil 已提交
1057 1058
		ret = btrfs_mksubvol(&file->f_path, name, namelen,
				     BTRFS_I(src_inode)->root,
L
Li Zefan 已提交
1059
				     transid, readonly);
1060
		fput(src_file);
1061
	}
C
Christoph Hellwig 已提交
1062
out:
S
Sage Weil 已提交
1063 1064 1065 1066
	return ret;
}

static noinline int btrfs_ioctl_snap_create(struct file *file,
1067
					    void __user *arg, int subvol)
S
Sage Weil 已提交
1068
{
1069
	struct btrfs_ioctl_vol_args *vol_args;
S
Sage Weil 已提交
1070 1071
	int ret;

1072 1073 1074 1075
	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
1076

1077
	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1078 1079
					      vol_args->fd, subvol,
					      NULL, false);
1080

1081 1082 1083
	kfree(vol_args);
	return ret;
}
1084

1085 1086 1087 1088 1089 1090 1091
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
1092
	bool readonly = false;
1093

1094 1095 1096 1097
	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';
1098

L
Li Zefan 已提交
1099 1100 1101
	if (vol_args->flags &
	    ~(BTRFS_SUBVOL_CREATE_ASYNC | BTRFS_SUBVOL_RDONLY)) {
		ret = -EOPNOTSUPP;
1102
		goto out;
S
Sage Weil 已提交
1103
	}
1104 1105 1106

	if (vol_args->flags & BTRFS_SUBVOL_CREATE_ASYNC)
		ptr = &transid;
L
Li Zefan 已提交
1107 1108
	if (vol_args->flags & BTRFS_SUBVOL_RDONLY)
		readonly = true;
1109 1110

	ret = btrfs_ioctl_snap_create_transid(file, vol_args->name,
L
Li Zefan 已提交
1111 1112
					      vol_args->fd, subvol,
					      ptr, readonly);
1113 1114 1115 1116 1117 1118

	if (ret == 0 && ptr &&
	    copy_to_user(arg +
			 offsetof(struct btrfs_ioctl_vol_args_v2,
				  transid), ptr, sizeof(*ptr)))
		ret = -EFAULT;
1119
out:
C
Christoph Hellwig 已提交
1120 1121 1122 1123
	kfree(vol_args);
	return ret;
}

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 1159 1160 1161 1162 1163 1164
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;

1165
	if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
1166 1167 1168 1169 1170
		return -EINVAL;

	if (flags & ~BTRFS_SUBVOL_RDONLY)
		return -EOPNOTSUPP;

1171
	if (!inode_owner_or_capable(inode))
1172 1173
		return -EACCES;

1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193
	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;
	}

1194
	ret = btrfs_update_root(trans, root->fs_info->tree_root,
1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
				&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;
}

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 1236 1237 1238 1239 1240 1241
/*
 * 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;
}

1242 1243 1244
static noinline int key_in_sk(struct btrfs_key *key,
			      struct btrfs_ioctl_search_key *sk)
{
1245 1246 1247 1248 1249 1250 1251 1252 1253
	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)
1254
		return 0;
1255 1256 1257 1258 1259 1260 1261

	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)
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 1323 1324 1325 1326 1327 1328
		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;
		}
1329
		found++;
1330 1331 1332 1333 1334

		if (*num_found >= sk->nr_items)
			break;
	}
advance_key:
1335 1336
	ret = 0;
	if (key->offset < (u64)-1 && key->offset < sk->max_offset)
1337
		key->offset++;
1338 1339
	else if (key->type < (u8)-1 && key->type < sk->max_type) {
		key->offset = 0;
1340
		key->type++;
1341 1342 1343
	} else if (key->objectid < (u64)-1 && key->objectid < sk->max_objectid) {
		key->offset = 0;
		key->type = 0;
1344
		key->objectid++;
1345 1346
	} else
		ret = 1;
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 1421 1422 1423 1424 1425 1426
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
1427 1428 1429
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
1430 1431 1432 1433 1434 1435 1436 1437 1438

	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;
}

1439
/*
1440 1441 1442
 * Search INODE_REFs to identify path name of 'dirid' directory
 * in a 'tree_id' tree. and sets path name to 'name'.
 */
1443 1444 1445 1446 1447
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;
1448
	char *ptr;
1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465
	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;

1466
	ptr = &name[BTRFS_INO_LOOKUP_PATH_MAX];
1467 1468 1469 1470 1471 1472 1473

	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);
1474 1475
		ret = -ENOENT;
		goto out;
1476 1477 1478 1479
	}

	key.objectid = dirid;
	key.type = BTRFS_INODE_REF_KEY;
1480
	key.offset = (u64)-1;
1481 1482 1483 1484 1485 1486 1487 1488

	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];
1489 1490
		if (ret > 0 && slot > 0)
			slot--;
1491 1492 1493
		btrfs_item_key_to_cpu(l, &key, slot);

		if (ret > 0 && (key.objectid != dirid ||
1494 1495
				key.type != BTRFS_INODE_REF_KEY)) {
			ret = -ENOENT;
1496
			goto out;
1497
		}
1498 1499 1500 1501 1502

		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;
1503
		if (ptr < name)
1504 1505 1506 1507 1508 1509 1510 1511 1512 1513
			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;
1514
		key.offset = (u64)-1;
1515 1516 1517
		dirid = key.objectid;

	}
1518
	if (ptr < name)
1519
		goto out;
1520
	memcpy(name, ptr, total_len);
1521 1522 1523 1524
	name[total_len]='\0';
	ret = 0;
out:
	btrfs_free_path(path);
1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537
	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
1538 1539 1540
	args = memdup_user(argp, sizeof(*args));
	if (IS_ERR(args))
		return PTR_ERR(args);
1541

1542 1543
	inode = fdentry(file)->d_inode;

1544 1545 1546
	if (args->treeid == 0)
		args->treeid = BTRFS_I(inode)->root->root_key.objectid;

1547 1548 1549 1550 1551 1552 1553 1554
	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);
1555 1556 1557
	return ret;
}

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 1596 1597 1598 1599 1600 1601
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;
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 1636 1637 1638 1639 1640 1641
	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;
	}

1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657
	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;

1658 1659 1660
	trans = btrfs_start_transaction(root, 0);
	if (IS_ERR(trans)) {
		err = PTR_ERR(trans);
1661
		goto out_up_write;
1662 1663 1664
	}
	trans->block_rsv = &root->fs_info->global_block_rsv;

1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677
	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);

1678 1679 1680 1681 1682 1683
	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);
	}
1684

S
Sage Weil 已提交
1685
	ret = btrfs_end_transaction(trans, root);
1686 1687 1688 1689 1690 1691 1692
	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) {
1693
		shrink_dcache_sb(root->fs_info->sb);
1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706
		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
1707
static int btrfs_ioctl_defrag(struct file *file, void __user *argp)
C
Christoph Hellwig 已提交
1708 1709 1710
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
C
Chris Mason 已提交
1711
	struct btrfs_ioctl_defrag_range_args *range;
Y
Yan Zheng 已提交
1712 1713
	int ret;

L
Li Zefan 已提交
1714 1715 1716
	if (btrfs_root_readonly(root))
		return -EROFS;

Y
Yan Zheng 已提交
1717 1718 1719
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		return ret;
C
Christoph Hellwig 已提交
1720 1721 1722

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
1723 1724 1725 1726
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
1727 1728 1729 1730
		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
1731 1732
		break;
	case S_IFREG:
1733 1734 1735 1736
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Chris Mason 已提交
1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748

		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);
1749
				goto out;
C
Chris Mason 已提交
1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
			}
			/* 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;
		}
1760
		ret = btrfs_defrag_file(file, range);
C
Chris Mason 已提交
1761
		kfree(range);
C
Christoph Hellwig 已提交
1762
		break;
1763 1764
	default:
		ret = -EINVAL;
C
Christoph Hellwig 已提交
1765
	}
1766
out:
1767
	mnt_drop_write(file->f_path.mnt);
1768
	return ret;
C
Christoph Hellwig 已提交
1769 1770
}

1771
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
1772 1773 1774 1775
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

1776 1777 1778
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

L
Li Zefan 已提交
1779 1780 1781
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
1782

1783
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1784 1785 1786 1787 1788 1789
	ret = btrfs_init_new_device(root, vol_args->name);

	kfree(vol_args);
	return ret;
}

1790
static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
1791 1792 1793 1794
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

1795 1796 1797
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

Y
Yan Zheng 已提交
1798 1799 1800
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

L
Li Zefan 已提交
1801 1802 1803
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
1804

1805
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
1806 1807 1808 1809 1810 1811
	ret = btrfs_rm_device(root, vol_args->name);

	kfree(vol_args);
	return ret;
}

1812 1813
static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
				       u64 off, u64 olen, u64 destoff)
C
Christoph Hellwig 已提交
1814 1815 1816 1817 1818 1819 1820 1821
{
	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
1822 1823
	char *buf;
	struct btrfs_key key;
C
Christoph Hellwig 已提交
1824 1825
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
1826
	int ret;
1827 1828 1829
	u64 len = olen;
	u64 bs = root->fs_info->sb->s_blocksize;
	u64 hint_byte;
1830

1831 1832 1833 1834 1835 1836 1837 1838 1839 1840
	/*
	 * 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)?
	 */

1841
	/* the destination must be opened for writing */
1842
	if (!(file->f_mode & FMODE_WRITE) || (file->f_flags & O_APPEND))
1843 1844
		return -EINVAL;

L
Li Zefan 已提交
1845 1846 1847
	if (btrfs_root_readonly(root))
		return -EROFS;

Y
Yan Zheng 已提交
1848 1849 1850 1851
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		return ret;

1852
	src_file = fget(srcfd);
1853 1854 1855 1856
	if (!src_file) {
		ret = -EBADF;
		goto out_drop_write;
	}
1857

C
Christoph Hellwig 已提交
1858 1859
	src = src_file->f_dentry->d_inode;

1860 1861 1862 1863
	ret = -EINVAL;
	if (src == inode)
		goto out_fput;

1864 1865 1866 1867
	/* the src must be open for reading */
	if (!(src_file->f_mode & FMODE_READ))
		goto out_fput;

Y
Yan Zheng 已提交
1868 1869 1870 1871
	ret = -EISDIR;
	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
		goto out_fput;

C
Christoph Hellwig 已提交
1872
	ret = -EXDEV;
Y
Yan Zheng 已提交
1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883
	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
1884
		goto out_fput;
Y
Yan Zheng 已提交
1885 1886
	}
	path->reada = 2;
C
Christoph Hellwig 已提交
1887 1888

	if (inode < src) {
1889 1890
		mutex_lock_nested(&inode->i_mutex, I_MUTEX_PARENT);
		mutex_lock_nested(&src->i_mutex, I_MUTEX_CHILD);
C
Christoph Hellwig 已提交
1891
	} else {
1892 1893
		mutex_lock_nested(&src->i_mutex, I_MUTEX_PARENT);
		mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
C
Christoph Hellwig 已提交
1894 1895
	}

1896 1897
	/* determine range to clone */
	ret = -EINVAL;
1898
	if (off + len > src->i_size || off + len < off)
C
Christoph Hellwig 已提交
1899
		goto out_unlock;
1900 1901 1902 1903
	if (len == 0)
		olen = len = src->i_size - off;
	/* if we extend to eof, continue to block boundary */
	if (off + len == src->i_size)
1904
		len = ALIGN(src->i_size, bs) - off;
1905 1906

	/* verify the end result is block aligned */
1907 1908
	if (!IS_ALIGNED(off, bs) || !IS_ALIGNED(off + len, bs) ||
	    !IS_ALIGNED(destoff, bs))
1909 1910
		goto out_unlock;

C
Christoph Hellwig 已提交
1911 1912 1913
	/* do any pending delalloc/csum calc on src, one way or
	   another, and lock file content */
	while (1) {
Z
Zheng Yan 已提交
1914
		struct btrfs_ordered_extent *ordered;
1915
		lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
1916 1917 1918 1919
		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
1920
			break;
1921
		unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
Y
Yan Zheng 已提交
1922 1923
		if (ordered)
			btrfs_put_ordered_extent(ordered);
1924
		btrfs_wait_ordered_range(src, off, len);
C
Christoph Hellwig 已提交
1925 1926
	}

1927
	/* clone data */
C
Christoph Hellwig 已提交
1928
	key.objectid = src->i_ino;
Y
Yan Zheng 已提交
1929 1930
	key.type = BTRFS_EXTENT_DATA_KEY;
	key.offset = 0;
C
Christoph Hellwig 已提交
1931 1932 1933 1934 1935 1936

	while (1) {
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
1937
		ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
C
Christoph Hellwig 已提交
1938 1939 1940
		if (ret < 0)
			goto out;

Y
Yan Zheng 已提交
1941 1942
		nritems = btrfs_header_nritems(path->nodes[0]);
		if (path->slots[0] >= nritems) {
C
Christoph Hellwig 已提交
1943 1944 1945 1946 1947
			ret = btrfs_next_leaf(root, path);
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
1948
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
1949 1950 1951 1952
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
1953
		btrfs_item_key_to_cpu(leaf, &key, slot);
1954
		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
C
Christoph Hellwig 已提交
1955 1956 1957
		    key.objectid != src->i_ino)
			break;

1958 1959 1960
		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
1961 1962
			u32 size;
			struct btrfs_key new_key;
1963 1964 1965
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
1966
			u64 endoff;
Z
Zheng Yan 已提交
1967 1968 1969 1970 1971

			size = btrfs_item_size_nr(leaf, slot);
			read_extent_buffer(leaf, buf,
					   btrfs_item_ptr_offset(leaf, slot),
					   size);
1972 1973 1974 1975 1976

			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);
1977 1978
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
1979 1980 1981 1982
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
1983
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
1984 1985
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
1986 1987 1988 1989 1990
			} 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
1991 1992
			btrfs_release_path(root, path);

1993
			if (key.offset + datal <= off ||
1994 1995 1996
			    key.offset >= off+len)
				goto next;

Z
Zheng Yan 已提交
1997 1998
			memcpy(&new_key, &key, sizeof(new_key));
			new_key.objectid = inode->i_ino;
1999 2000 2001 2002
			if (off <= key.offset)
				new_key.offset = key.offset + destoff - off;
			else
				new_key.offset = destoff;
Z
Zheng Yan 已提交
2003

2004 2005 2006 2007 2008 2009
			trans = btrfs_start_transaction(root, 1);
			if (IS_ERR(trans)) {
				ret = PTR_ERR(trans);
				goto out;
			}

2010 2011
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
				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);

2026 2027
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
2028
				BUG_ON(ret);
2029 2030 2031 2032

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
2033 2034
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
2035

2036
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
2037
						struct btrfs_file_extent_item);
2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048

				/* 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
2049
					ret = btrfs_inc_extent_ref(trans, root,
2050 2051 2052 2053
							disko, diskl, 0,
							root->root_key.objectid,
							inode->i_ino,
							new_key.offset - datao);
Z
Zheng Yan 已提交
2054
					BUG_ON(ret);
C
Christoph Hellwig 已提交
2055
				}
2056 2057 2058 2059 2060 2061 2062
			} 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
2063

2064 2065
				if (key.offset + datal > off+len)
					trim = key.offset + datal - (off+len);
C
Chris Mason 已提交
2066

2067 2068
				if (comp && (skip || trim)) {
					ret = -EINVAL;
2069
					btrfs_end_transaction(trans, root);
2070 2071 2072 2073
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
2074 2075 2076 2077 2078 2079 2080

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

2081 2082
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
2083
				BUG_ON(ret);
2084 2085

				if (skip) {
C
Chris Mason 已提交
2086 2087
					u32 start =
					  btrfs_file_extent_calc_inline_size(0);
2088 2089 2090 2091 2092 2093 2094 2095 2096 2097
					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
2098
			}
2099 2100

			btrfs_mark_buffer_dirty(leaf);
2101
			btrfs_release_path(root, path);
2102

2103
			inode->i_mtime = inode->i_ctime = CURRENT_TIME;
2104 2105 2106 2107 2108 2109 2110

			/*
			 * 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;
2111 2112
			if (endoff > destoff+olen)
				endoff = destoff+olen;
2113 2114 2115
			if (endoff > inode->i_size)
				btrfs_i_size_write(inode, endoff);

2116 2117 2118 2119 2120
			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
2121
next:
Z
Zheng Yan 已提交
2122
		btrfs_release_path(root, path);
C
Christoph Hellwig 已提交
2123 2124 2125 2126
		key.offset++;
	}
	ret = 0;
out:
Y
Yan Zheng 已提交
2127
	btrfs_release_path(root, path);
2128
	unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
C
Christoph Hellwig 已提交
2129 2130 2131
out_unlock:
	mutex_unlock(&src->i_mutex);
	mutex_unlock(&inode->i_mutex);
Y
Yan Zheng 已提交
2132 2133
	vfree(buf);
	btrfs_free_path(path);
C
Christoph Hellwig 已提交
2134 2135
out_fput:
	fput(src_file);
2136 2137
out_drop_write:
	mnt_drop_write(file->f_path.mnt);
C
Christoph Hellwig 已提交
2138 2139 2140
	return ret;
}

2141
static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
2142 2143 2144
{
	struct btrfs_ioctl_clone_range_args args;

2145
	if (copy_from_user(&args, argp, sizeof(args)))
2146 2147 2148 2149 2150
		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
2151 2152 2153 2154 2155 2156
/*
 * 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.
 */
2157
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
2158 2159 2160 2161
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
2162
	int ret;
C
Christoph Hellwig 已提交
2163

2164
	ret = -EPERM;
2165
	if (!capable(CAP_SYS_ADMIN))
2166
		goto out;
2167

2168 2169
	ret = -EINPROGRESS;
	if (file->private_data)
C
Christoph Hellwig 已提交
2170
		goto out;
2171

L
Li Zefan 已提交
2172 2173 2174 2175
	ret = -EROFS;
	if (btrfs_root_readonly(root))
		goto out;

Y
Yan Zheng 已提交
2176 2177 2178 2179
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		goto out;

2180 2181 2182 2183
	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans++;
	mutex_unlock(&root->fs_info->trans_mutex);

2184
	ret = -ENOMEM;
2185
	trans = btrfs_start_ioctl_transaction(root);
2186
	if (IS_ERR(trans))
2187 2188 2189 2190 2191 2192 2193 2194 2195 2196
		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
2197 2198 2199 2200
out:
	return ret;
}

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 2236 2237 2238 2239 2240 2241
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);
2242
	if (IS_ERR(trans)) {
2243
		btrfs_free_path(path);
2244
		return PTR_ERR(trans);
2245 2246 2247 2248 2249
	}

	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);
2250
	if (IS_ERR_OR_NULL(di)) {
2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273
		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;
}

2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289
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
2290 2291 2292 2293 2294
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;
2295
	struct btrfs_ioctl_space_info *dest_orig;
2296
	struct btrfs_ioctl_space_info __user *user_dest;
J
Josef Bacik 已提交
2297
	struct btrfs_space_info *info;
2298 2299 2300 2301 2302
	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;
2303
	int alloc_size;
J
Josef Bacik 已提交
2304
	int ret = 0;
2305
	u64 slot_count = 0;
2306
	int i, c;
J
Josef Bacik 已提交
2307 2308 2309 2310 2311 2312

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

2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336
	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);
	}
2337 2338 2339 2340 2341 2342

	/* space_slots == 0 means they are asking for a count */
	if (space_args.space_slots == 0) {
		space_args.total_spaces = slot_count;
		goto out;
	}
2343

2344
	slot_count = min_t(u64, space_args.space_slots, slot_count);
2345

2346
	alloc_size = sizeof(*dest) * slot_count;
2347

2348 2349 2350 2351 2352 2353
	/* 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
2354
	space_args.total_spaces = 0;
2355 2356 2357 2358
	dest = kmalloc(alloc_size, GFP_NOFS);
	if (!dest)
		return -ENOMEM;
	dest_orig = dest;
J
Josef Bacik 已提交
2359

2360
	/* now we have a buffer to copy into */
2361 2362 2363
	for (i = 0; i < num_types; i++) {
		struct btrfs_space_info *tmp;

2364 2365 2366
		if (!slot_count)
			break;

2367 2368 2369 2370 2371 2372 2373 2374 2375 2376
		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();
2377

2378 2379 2380 2381 2382 2383 2384 2385 2386 2387
		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++;
2388
				slot_count--;
2389
			}
2390 2391
			if (!slot_count)
				break;
2392 2393
		}
		up_read(&info->groups_sem);
J
Josef Bacik 已提交
2394 2395
	}

2396 2397 2398 2399 2400 2401 2402 2403 2404
	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
2405 2406 2407 2408 2409
		ret = -EFAULT;

	return ret;
}

C
Christoph Hellwig 已提交
2410 2411 2412 2413 2414 2415 2416 2417 2418 2419 2420 2421 2422
/*
 * 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;
2423 2424
	if (!trans)
		return -EINVAL;
C
Christoph Hellwig 已提交
2425
	file->private_data = NULL;
2426

2427 2428
	btrfs_end_transaction(trans, root);

2429 2430 2431 2432
	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans--;
	mutex_unlock(&root->fs_info->trans_mutex);

2433
	mnt_drop_write(file->f_path.mnt);
2434
	return 0;
C
Christoph Hellwig 已提交
2435 2436
}

2437 2438 2439 2440 2441
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
2442
	int ret;
2443 2444

	trans = btrfs_start_transaction(root, 0);
2445 2446
	if (IS_ERR(trans))
		return PTR_ERR(trans);
2447
	transid = trans->transid;
T
Tsutomu Itoh 已提交
2448
	ret = btrfs_commit_transaction_async(trans, root, 0);
2449 2450
	if (ret) {
		btrfs_end_transaction(trans, root);
T
Tsutomu Itoh 已提交
2451
		return ret;
2452
	}
2453 2454 2455 2456 2457 2458 2459 2460 2461 2462 2463 2464 2465 2466 2467 2468 2469 2470 2471 2472 2473

	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
2474 2475 2476 2477
long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
2478
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
2479 2480

	switch (cmd) {
2481 2482 2483 2484 2485 2486
	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);
2487 2488
	case FITRIM:
		return btrfs_ioctl_fitrim(file, argp);
C
Christoph Hellwig 已提交
2489
	case BTRFS_IOC_SNAP_CREATE:
2490
		return btrfs_ioctl_snap_create(file, argp, 0);
2491
	case BTRFS_IOC_SNAP_CREATE_V2:
2492
		return btrfs_ioctl_snap_create_v2(file, argp, 0);
2493
	case BTRFS_IOC_SUBVOL_CREATE:
2494
		return btrfs_ioctl_snap_create(file, argp, 1);
2495 2496
	case BTRFS_IOC_SNAP_DESTROY:
		return btrfs_ioctl_snap_destroy(file, argp);
2497 2498 2499 2500
	case BTRFS_IOC_SUBVOL_GETFLAGS:
		return btrfs_ioctl_subvol_getflags(file, argp);
	case BTRFS_IOC_SUBVOL_SETFLAGS:
		return btrfs_ioctl_subvol_setflags(file, argp);
2501 2502
	case BTRFS_IOC_DEFAULT_SUBVOL:
		return btrfs_ioctl_default_subvol(file, argp);
C
Christoph Hellwig 已提交
2503
	case BTRFS_IOC_DEFRAG:
C
Chris Mason 已提交
2504 2505 2506
		return btrfs_ioctl_defrag(file, NULL);
	case BTRFS_IOC_DEFRAG_RANGE:
		return btrfs_ioctl_defrag(file, argp);
C
Christoph Hellwig 已提交
2507
	case BTRFS_IOC_RESIZE:
2508
		return btrfs_ioctl_resize(root, argp);
C
Christoph Hellwig 已提交
2509
	case BTRFS_IOC_ADD_DEV:
2510
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
2511
	case BTRFS_IOC_RM_DEV:
2512
		return btrfs_ioctl_rm_dev(root, argp);
C
Christoph Hellwig 已提交
2513 2514 2515
	case BTRFS_IOC_BALANCE:
		return btrfs_balance(root->fs_info->dev_root);
	case BTRFS_IOC_CLONE:
2516 2517
		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
	case BTRFS_IOC_CLONE_RANGE:
2518
		return btrfs_ioctl_clone_range(file, argp);
C
Christoph Hellwig 已提交
2519 2520 2521 2522
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
2523 2524 2525 2526
	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
2527 2528
	case BTRFS_IOC_SPACE_INFO:
		return btrfs_ioctl_space_info(root, argp);
C
Christoph Hellwig 已提交
2529 2530 2531
	case BTRFS_IOC_SYNC:
		btrfs_sync_fs(file->f_dentry->d_sb, 1);
		return 0;
2532 2533 2534 2535
	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
2536 2537 2538 2539
	}

	return -ENOTTY;
}