ioctl.c 31.7 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/smp_lock.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 "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;
}

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;

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

	if (flags & ~(FS_IMMUTABLE_FL | FS_APPEND_FL | \
		      FS_NOATIME_FL | FS_NODUMP_FL | \
		      FS_SYNC_FL | FS_DIRSYNC_FL))
		return -EOPNOTSUPP;
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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;


	trans = btrfs_join_transaction(root, 1);
	BUG_ON(!trans);

	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);
 out_unlock:
	mutex_unlock(&inode->i_mutex);
	return 0;
}

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 create_subvol(struct btrfs_root *root,
				  struct dentry *dentry,
				  char *name, int namelen)
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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;
	struct btrfs_root *new_root = root;
	struct inode *dir;
	int ret;
	int err;
	u64 objectid;
	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
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	u64 index = 0;
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	unsigned long nr = 1;

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	ret = btrfs_check_metadata_free_space(root);
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	if (ret)
		goto fail_commit;

	trans = btrfs_start_transaction(root, 1);
	BUG_ON(!trans);

	ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
				       0, &objectid);
	if (ret)
		goto fail;

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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);

	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);
	btrfs_set_root_used(&root_item, 0);
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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;

	/*
	 * insert the directory item
	 */
	key.offset = (u64)-1;
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	dir = dentry->d_parent->d_inode;
	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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	/* add the backref first */
	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
				 objectid, BTRFS_ROOT_BACKREF_KEY,
				 root->root_key.objectid,
				 dir->i_ino, index, name, namelen);

	BUG_ON(ret);

	/* now add the forward ref */
	ret = btrfs_add_root_ref(trans, root->fs_info->tree_root,
				 root->root_key.objectid, BTRFS_ROOT_REF_KEY,
				 objectid,
				 dir->i_ino, index, name, namelen);

	BUG_ON(ret);

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	ret = btrfs_commit_transaction(trans, root);
	if (ret)
		goto fail_commit;

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	new_root = btrfs_read_fs_root_no_name(root->fs_info, &key);
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	BUG_ON(!new_root);

	trans = btrfs_start_transaction(new_root, 1);
	BUG_ON(!trans);

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	ret = btrfs_create_subvol_root(trans, new_root, dentry, new_dirid,
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				       BTRFS_I(dir)->block_group);
	if (ret)
		goto fail;

fail:
	nr = trans->blocks_used;
	err = btrfs_commit_transaction(trans, new_root);
	if (err && !ret)
		ret = err;
fail_commit:
	btrfs_btree_balance_dirty(root, nr);
	return ret;
}

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static int create_snapshot(struct btrfs_root *root, struct dentry *dentry,
			   char *name, int namelen)
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{
	struct btrfs_pending_snapshot *pending_snapshot;
	struct btrfs_trans_handle *trans;
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	int ret = 0;
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	int err;
	unsigned long nr = 0;

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

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	ret = btrfs_check_metadata_free_space(root);
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	if (ret)
		goto fail_unlock;

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	pending_snapshot = kzalloc(sizeof(*pending_snapshot), GFP_NOFS);
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	if (!pending_snapshot) {
		ret = -ENOMEM;
		goto fail_unlock;
	}
	pending_snapshot->name = kmalloc(namelen + 1, GFP_NOFS);
	if (!pending_snapshot->name) {
		ret = -ENOMEM;
		kfree(pending_snapshot);
		goto fail_unlock;
	}
	memcpy(pending_snapshot->name, name, namelen);
	pending_snapshot->name[namelen] = '\0';
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	pending_snapshot->dentry = dentry;
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	trans = btrfs_start_transaction(root, 1);
	BUG_ON(!trans);
	pending_snapshot->root = root;
	list_add(&pending_snapshot->list,
		 &trans->transaction->pending_snapshots);
	err = btrfs_commit_transaction(trans, root);

fail_unlock:
	btrfs_btree_balance_dirty(root, nr);
	return ret;
}

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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.
 */
static noinline int btrfs_mksubvol(struct path *parent, char *name,
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				   int mode, int namelen,
				   struct btrfs_root *snap_src)
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{
	struct dentry *dentry;
	int error;

	mutex_lock_nested(&parent->dentry->d_inode->i_mutex, I_MUTEX_PARENT);

	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;

	if (!IS_POSIXACL(parent->dentry->d_inode))
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		mode &= ~current_umask();
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	error = mnt_want_write(parent->mnt);
	if (error)
		goto out_dput;

	error = btrfs_may_create(parent->dentry->d_inode, dentry);
	if (error)
		goto out_drop_write;

	/*
	 * Actually perform the low-level subvolume creation after all
	 * this VFS fuzz.
	 *
	 * Eventually we want to pass in an inode under which we create this
	 * subvolume, but for now all are under the filesystem root.
	 *
	 * Also we should pass on the mode eventually to allow creating new
	 * subvolume with specific mode bits.
	 */
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	if (snap_src) {
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		struct dentry *dir = dentry->d_parent;
		struct dentry *test = dir->d_parent;
		struct btrfs_path *path = btrfs_alloc_path();
		int ret;
		u64 test_oid;
		u64 parent_oid = BTRFS_I(dir->d_inode)->root->root_key.objectid;

		test_oid = snap_src->root_key.objectid;

		ret = btrfs_find_root_ref(snap_src->fs_info->tree_root,
					  path, parent_oid, test_oid);
		if (ret == 0)
			goto create;
		btrfs_release_path(snap_src->fs_info->tree_root, path);

		/* we need to make sure we aren't creating a directory loop
		 * by taking a snapshot of something that has our current
		 * subvol in its directory tree.  So, this loops through
		 * the dentries and checks the forward refs for each subvolume
		 * to see if is references the subvolume where we are
		 * placing this new snapshot.
		 */
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		while (1) {
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			if (!test ||
			    dir == snap_src->fs_info->sb->s_root ||
			    test == snap_src->fs_info->sb->s_root ||
			    test->d_inode->i_sb != snap_src->fs_info->sb) {
				break;
			}
			if (S_ISLNK(test->d_inode->i_mode)) {
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				printk(KERN_INFO "Btrfs symlink in snapshot "
				       "path, failed\n");
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				error = -EMLINK;
				btrfs_free_path(path);
				goto out_drop_write;
			}
			test_oid =
				BTRFS_I(test->d_inode)->root->root_key.objectid;
			ret = btrfs_find_root_ref(snap_src->fs_info->tree_root,
				  path, test_oid, parent_oid);
			if (ret == 0) {
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				printk(KERN_INFO "Btrfs snapshot creation "
				       "failed, looping\n");
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				error = -EMLINK;
				btrfs_free_path(path);
				goto out_drop_write;
			}
			btrfs_release_path(snap_src->fs_info->tree_root, path);
			test = test->d_parent;
		}
create:
		btrfs_free_path(path);
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		error = create_snapshot(snap_src, dentry, name, namelen);
	} else {
		error = create_subvol(BTRFS_I(parent->dentry->d_inode)->root,
				      dentry, name, namelen);
	}
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	if (error)
		goto out_drop_write;

	fsnotify_mkdir(parent->dentry->d_inode, dentry);
out_drop_write:
	mnt_drop_write(parent->mnt);
out_dput:
	dput(dentry);
out_unlock:
	mutex_unlock(&parent->dentry->d_inode->i_mutex);
	return error;
}


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static int btrfs_defrag_file(struct file *file)
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{
	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;
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	struct btrfs_ordered_extent *ordered;
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	struct page *page;
	unsigned long last_index;
	unsigned long ra_pages = root->fs_info->bdi.ra_pages;
	unsigned long total_read = 0;
	u64 page_start;
	u64 page_end;
	unsigned long i;
	int ret;

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	ret = btrfs_check_data_free_space(root, inode, inode->i_size);
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	if (ret)
		return -ENOSPC;

	mutex_lock(&inode->i_mutex);
	last_index = inode->i_size >> PAGE_CACHE_SHIFT;
	for (i = 0; i <= last_index; i++) {
		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++;
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again:
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		page = grab_cache_page(inode->i_mapping, i);
		if (!page)
			goto out_unlock;
		if (!PageUptodate(page)) {
			btrfs_readpage(NULL, page);
			lock_page(page);
			if (!PageUptodate(page)) {
				unlock_page(page);
				page_cache_release(page);
				goto out_unlock;
			}
		}

		wait_on_page_writeback(page);

		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);
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		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);

593 594 595 596 597 598
		/*
		 * this makes sure page_mkwrite is called on the
		 * page if it is dirtied again later
		 */
		clear_page_dirty_for_io(page);

599
		btrfs_set_extent_delalloc(inode, page_start, page_end);
C
Christoph Hellwig 已提交
600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626

		unlock_extent(io_tree, page_start, page_end, GFP_NOFS);
		set_page_dirty(page);
		unlock_page(page);
		page_cache_release(page);
		balance_dirty_pages_ratelimited_nr(inode->i_mapping, 1);
	}

out_unlock:
	mutex_unlock(&inode->i_mutex);
	return 0;
}

static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
{
	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 namelen;
	int mod = 0;

Y
Yan Zheng 已提交
627 628 629
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

630 631 632
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

L
Li Zefan 已提交
633 634 635
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
636 637

	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
638 639
	namelen = strlen(vol_args->name);

640
	mutex_lock(&root->fs_info->volume_mutex);
C
Christoph Hellwig 已提交
641 642 643 644 645 646 647 648
	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);
649 650
		printk(KERN_INFO "resizing devid %llu\n",
		       (unsigned long long)devid);
C
Christoph Hellwig 已提交
651
	}
Y
Yan Zheng 已提交
652
	device = btrfs_find_device(root, devid, NULL, NULL);
C
Christoph Hellwig 已提交
653
	if (!device) {
654 655
		printk(KERN_INFO "resizer unable to find device %llu\n",
		       (unsigned long long)devid);
C
Christoph Hellwig 已提交
656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711
		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++;
		}
		new_size = btrfs_parse_size(sizestr);
		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) {
		trans = btrfs_start_transaction(root, 1);
		ret = btrfs_grow_device(trans, device, new_size);
		btrfs_commit_transaction(trans, root);
	} else {
		ret = btrfs_shrink_device(device, new_size);
	}

out_unlock:
712
	mutex_unlock(&root->fs_info->volume_mutex);
C
Christoph Hellwig 已提交
713 714 715 716
	kfree(vol_args);
	return ret;
}

717
static noinline int btrfs_ioctl_snap_create(struct file *file,
718
					    void __user *arg, int subvol)
C
Christoph Hellwig 已提交
719
{
720
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
C
Christoph Hellwig 已提交
721 722 723
	struct btrfs_ioctl_vol_args *vol_args;
	struct btrfs_dir_item *di;
	struct btrfs_path *path;
724
	struct file *src_file;
C
Christoph Hellwig 已提交
725 726
	u64 root_dirid;
	int namelen;
727
	int ret = 0;
C
Christoph Hellwig 已提交
728

Y
Yan Zheng 已提交
729 730 731
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

L
Li Zefan 已提交
732 733 734
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
735

736
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764
	namelen = strlen(vol_args->name);
	if (strchr(vol_args->name, '/')) {
		ret = -EINVAL;
		goto out;
	}

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

	root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
	di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
			    path, root_dirid,
			    vol_args->name, namelen, 0);
	btrfs_free_path(path);

	if (di && !IS_ERR(di)) {
		ret = -EEXIST;
		goto out;
	}

	if (IS_ERR(di)) {
		ret = PTR_ERR(di);
		goto out;
	}

765
	if (subvol) {
766 767
		ret = btrfs_mksubvol(&file->f_path, vol_args->name,
				     file->f_path.dentry->d_inode->i_mode,
768
				     namelen, NULL);
769
	} else {
770 771 772 773 774 775 776 777 778
		struct inode *src_inode;
		src_file = fget(vol_args->fd);
		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
779 780
			printk(KERN_INFO "btrfs: Snapshot src from "
			       "another FS\n");
781 782 783 784 785 786 787 788
			ret = -EINVAL;
			fput(src_file);
			goto out;
		}
		ret = btrfs_mksubvol(&file->f_path, vol_args->name,
			     file->f_path.dentry->d_inode->i_mode,
			     namelen, BTRFS_I(src_inode)->root);
		fput(src_file);
789 790
	}

C
Christoph Hellwig 已提交
791 792 793 794 795 796 797 798 799
out:
	kfree(vol_args);
	return ret;
}

static int btrfs_ioctl_defrag(struct file *file)
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
Y
Yan Zheng 已提交
800 801 802 803 804
	int ret;

	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		return ret;
C
Christoph Hellwig 已提交
805 806 807

	switch (inode->i_mode & S_IFMT) {
	case S_IFDIR:
808 809 810 811
		if (!capable(CAP_SYS_ADMIN)) {
			ret = -EPERM;
			goto out;
		}
C
Christoph Hellwig 已提交
812 813 814 815
		btrfs_defrag_root(root, 0);
		btrfs_defrag_root(root->fs_info->extent_root, 0);
		break;
	case S_IFREG:
816 817 818 819
		if (!(file->f_mode & FMODE_WRITE)) {
			ret = -EINVAL;
			goto out;
		}
C
Christoph Hellwig 已提交
820 821 822
		btrfs_defrag_file(file);
		break;
	}
823
out:
824
	mnt_drop_write(file->f_path.mnt);
825
	return ret;
C
Christoph Hellwig 已提交
826 827
}

828
static long btrfs_ioctl_add_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
829 830 831 832
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

833 834 835
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

L
Li Zefan 已提交
836 837 838
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
839

840
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
841 842 843 844 845 846
	ret = btrfs_init_new_device(root, vol_args->name);

	kfree(vol_args);
	return ret;
}

847
static long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
C
Christoph Hellwig 已提交
848 849 850 851
{
	struct btrfs_ioctl_vol_args *vol_args;
	int ret;

852 853 854
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

Y
Yan Zheng 已提交
855 856 857
	if (root->fs_info->sb->s_flags & MS_RDONLY)
		return -EROFS;

L
Li Zefan 已提交
858 859 860
	vol_args = memdup_user(arg, sizeof(*vol_args));
	if (IS_ERR(vol_args))
		return PTR_ERR(vol_args);
C
Christoph Hellwig 已提交
861

862
	vol_args->name[BTRFS_PATH_NAME_MAX] = '\0';
C
Christoph Hellwig 已提交
863 864 865 866 867 868
	ret = btrfs_rm_device(root, vol_args->name);

	kfree(vol_args);
	return ret;
}

869 870
static long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
		u64 off, u64 olen, u64 destoff)
C
Christoph Hellwig 已提交
871 872 873 874 875 876 877 878
{
	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
879 880
	char *buf;
	struct btrfs_key key;
C
Christoph Hellwig 已提交
881 882
	u32 nritems;
	int slot;
Y
Yan Zheng 已提交
883
	int ret;
884 885 886
	u64 len = olen;
	u64 bs = root->fs_info->sb->s_blocksize;
	u64 hint_byte;
887

888 889 890 891 892 893 894 895 896 897
	/*
	 * 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)?
	 */

898 899 900 901
	/* the destination must be opened for writing */
	if (!(file->f_mode & FMODE_WRITE))
		return -EINVAL;

Y
Yan Zheng 已提交
902 903 904 905
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		return ret;

906
	src_file = fget(srcfd);
907 908 909 910
	if (!src_file) {
		ret = -EBADF;
		goto out_drop_write;
	}
C
Christoph Hellwig 已提交
911 912
	src = src_file->f_dentry->d_inode;

913 914 915 916
	ret = -EINVAL;
	if (src == inode)
		goto out_fput;

Y
Yan Zheng 已提交
917 918 919 920
	ret = -EISDIR;
	if (S_ISDIR(src->i_mode) || S_ISDIR(inode->i_mode))
		goto out_fput;

C
Christoph Hellwig 已提交
921
	ret = -EXDEV;
Y
Yan Zheng 已提交
922 923 924 925 926 927 928 929 930 931 932
	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
933
		goto out_fput;
Y
Yan Zheng 已提交
934 935
	}
	path->reada = 2;
C
Christoph Hellwig 已提交
936 937 938 939 940 941 942 943 944

	if (inode < src) {
		mutex_lock(&inode->i_mutex);
		mutex_lock(&src->i_mutex);
	} else {
		mutex_lock(&src->i_mutex);
		mutex_lock(&inode->i_mutex);
	}

945 946 947
	/* determine range to clone */
	ret = -EINVAL;
	if (off >= src->i_size || off + len > src->i_size)
C
Christoph Hellwig 已提交
948
		goto out_unlock;
949 950 951 952 953 954 955 956 957 958 959 960
	if (len == 0)
		olen = len = src->i_size - off;
	/* if we extend to eof, continue to block boundary */
	if (off + len == src->i_size)
		len = ((src->i_size + bs-1) & ~(bs-1))
			- off;

	/* verify the end result is block aligned */
	if ((off & (bs-1)) ||
	    ((off + len) & (bs-1)))
		goto out_unlock;

C
Christoph Hellwig 已提交
961 962 963
	/* do any pending delalloc/csum calc on src, one way or
	   another, and lock file content */
	while (1) {
Z
Zheng Yan 已提交
964
		struct btrfs_ordered_extent *ordered;
965 966
		lock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
		ordered = btrfs_lookup_first_ordered_extent(inode, off+len);
Y
Yan Zheng 已提交
967
		if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered)
C
Christoph Hellwig 已提交
968
			break;
969
		unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
Y
Yan Zheng 已提交
970 971
		if (ordered)
			btrfs_put_ordered_extent(ordered);
972
		btrfs_wait_ordered_range(src, off, off+len);
C
Christoph Hellwig 已提交
973 974
	}

Y
Yan Zheng 已提交
975 976 977
	trans = btrfs_start_transaction(root, 1);
	BUG_ON(!trans);

978
	/* punch hole in destination first */
979 980
	btrfs_drop_extents(trans, root, inode, off, off + len,
			   off + len, 0, &hint_byte);
981 982

	/* clone data */
C
Christoph Hellwig 已提交
983
	key.objectid = src->i_ino;
Y
Yan Zheng 已提交
984 985
	key.type = BTRFS_EXTENT_DATA_KEY;
	key.offset = 0;
C
Christoph Hellwig 已提交
986 987 988 989 990 991 992 993 994 995

	while (1) {
		/*
		 * note the key will change type as we walk through the
		 * tree.
		 */
		ret = btrfs_search_slot(trans, root, &key, path, 0, 0);
		if (ret < 0)
			goto out;

Y
Yan Zheng 已提交
996 997
		nritems = btrfs_header_nritems(path->nodes[0]);
		if (path->slots[0] >= nritems) {
C
Christoph Hellwig 已提交
998 999 1000 1001 1002
			ret = btrfs_next_leaf(root, path);
			if (ret < 0)
				goto out;
			if (ret > 0)
				break;
Y
Yan Zheng 已提交
1003
			nritems = btrfs_header_nritems(path->nodes[0]);
C
Christoph Hellwig 已提交
1004 1005 1006 1007
		}
		leaf = path->nodes[0];
		slot = path->slots[0];

Y
Yan Zheng 已提交
1008
		btrfs_item_key_to_cpu(leaf, &key, slot);
1009
		if (btrfs_key_type(&key) > BTRFS_EXTENT_DATA_KEY ||
C
Christoph Hellwig 已提交
1010 1011 1012
		    key.objectid != src->i_ino)
			break;

1013 1014 1015
		if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
			struct btrfs_file_extent_item *extent;
			int type;
Z
Zheng Yan 已提交
1016 1017
			u32 size;
			struct btrfs_key new_key;
1018 1019 1020
			u64 disko = 0, diskl = 0;
			u64 datao = 0, datal = 0;
			u8 comp;
Z
Zheng Yan 已提交
1021 1022 1023 1024 1025

			size = btrfs_item_size_nr(leaf, slot);
			read_extent_buffer(leaf, buf,
					   btrfs_item_ptr_offset(leaf, slot),
					   size);
1026 1027 1028 1029 1030

			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);
1031 1032
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
C
Chris Mason 已提交
1033 1034 1035 1036
				disko = btrfs_file_extent_disk_bytenr(leaf,
								      extent);
				diskl = btrfs_file_extent_disk_num_bytes(leaf,
								 extent);
1037
				datao = btrfs_file_extent_offset(leaf, extent);
C
Chris Mason 已提交
1038 1039
				datal = btrfs_file_extent_num_bytes(leaf,
								    extent);
1040 1041 1042 1043 1044
			} 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
1045 1046
			btrfs_release_path(root, path);

1047 1048 1049 1050
			if (key.offset + datal < off ||
			    key.offset >= off+len)
				goto next;

Z
Zheng Yan 已提交
1051 1052
			memcpy(&new_key, &key, sizeof(new_key));
			new_key.objectid = inode->i_ino;
1053
			new_key.offset = key.offset + destoff - off;
Z
Zheng Yan 已提交
1054

1055 1056
			if (type == BTRFS_FILE_EXTENT_REG ||
			    type == BTRFS_FILE_EXTENT_PREALLOC) {
1057 1058 1059 1060 1061 1062 1063 1064
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
				if (ret)
					goto out;

				leaf = path->nodes[0];
				slot = path->slots[0];
				write_extent_buffer(leaf, buf,
Z
Zheng Yan 已提交
1065 1066
					    btrfs_item_ptr_offset(leaf, slot),
					    size);
Y
Yan Zheng 已提交
1067

1068
				extent = btrfs_item_ptr(leaf, slot,
C
Christoph Hellwig 已提交
1069
						struct btrfs_file_extent_item);
1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087

				if (off > key.offset) {
					datao += off - key.offset;
					datal -= off - key.offset;
				}
				if (key.offset + datao + datal + key.offset >
				    off + len)
					datal = off + len - key.offset - datao;
				/* 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
1088
					ret = btrfs_inc_extent_ref(trans, root,
1089 1090 1091 1092
							disko, diskl, 0,
							root->root_key.objectid,
							inode->i_ino,
							new_key.offset - datao);
Z
Zheng Yan 已提交
1093
					BUG_ON(ret);
C
Christoph Hellwig 已提交
1094
				}
1095 1096 1097 1098 1099 1100 1101
			} 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
1102

1103 1104
				if (key.offset + datal > off+len)
					trim = key.offset + datal - (off+len);
C
Chris Mason 已提交
1105

1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117
				if (comp && (skip || trim)) {
					ret = -EINVAL;
					goto out;
				}
				size -= skip + trim;
				datal -= skip + trim;
				ret = btrfs_insert_empty_item(trans, root, path,
							      &new_key, size);
				if (ret)
					goto out;

				if (skip) {
C
Chris Mason 已提交
1118 1119
					u32 start =
					  btrfs_file_extent_calc_inline_size(0);
1120 1121 1122 1123 1124 1125 1126 1127 1128 1129
					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
1130
			}
1131 1132

			btrfs_mark_buffer_dirty(leaf);
Y
Yan Zheng 已提交
1133
		}
1134

C
Chris Mason 已提交
1135
next:
Z
Zheng Yan 已提交
1136
		btrfs_release_path(root, path);
C
Christoph Hellwig 已提交
1137 1138 1139 1140
		key.offset++;
	}
	ret = 0;
out:
Y
Yan Zheng 已提交
1141 1142 1143
	btrfs_release_path(root, path);
	if (ret == 0) {
		inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1144 1145
		if (destoff + olen > inode->i_size)
			btrfs_i_size_write(inode, destoff + olen);
Y
Yan Zheng 已提交
1146 1147 1148
		BTRFS_I(inode)->flags = BTRFS_I(src)->flags;
		ret = btrfs_update_inode(trans, root, inode);
	}
C
Christoph Hellwig 已提交
1149
	btrfs_end_transaction(trans, root);
1150
	unlock_extent(&BTRFS_I(src)->io_tree, off, off+len, GFP_NOFS);
Y
Yan Zheng 已提交
1151 1152
	if (ret)
		vmtruncate(inode, 0);
C
Christoph Hellwig 已提交
1153 1154 1155
out_unlock:
	mutex_unlock(&src->i_mutex);
	mutex_unlock(&inode->i_mutex);
Y
Yan Zheng 已提交
1156 1157
	vfree(buf);
	btrfs_free_path(path);
C
Christoph Hellwig 已提交
1158 1159
out_fput:
	fput(src_file);
1160 1161
out_drop_write:
	mnt_drop_write(file->f_path.mnt);
C
Christoph Hellwig 已提交
1162 1163 1164
	return ret;
}

1165
static long btrfs_ioctl_clone_range(struct file *file, void __user *argp)
1166 1167 1168
{
	struct btrfs_ioctl_clone_range_args args;

1169
	if (copy_from_user(&args, argp, sizeof(args)))
1170 1171 1172 1173 1174
		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
1175 1176 1177 1178 1179 1180
/*
 * 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.
 */
1181
static long btrfs_ioctl_trans_start(struct file *file)
C
Christoph Hellwig 已提交
1182 1183 1184 1185 1186 1187
{
	struct inode *inode = fdentry(file)->d_inode;
	struct btrfs_root *root = BTRFS_I(inode)->root;
	struct btrfs_trans_handle *trans;
	int ret = 0;

1188 1189 1190
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

C
Christoph Hellwig 已提交
1191 1192 1193 1194
	if (file->private_data) {
		ret = -EINPROGRESS;
		goto out;
	}
1195

Y
Yan Zheng 已提交
1196 1197 1198 1199
	ret = mnt_want_write(file->f_path.mnt);
	if (ret)
		goto out;

1200 1201 1202 1203 1204
	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans++;
	mutex_unlock(&root->fs_info->trans_mutex);

	trans = btrfs_start_ioctl_transaction(root, 0);
C
Christoph Hellwig 已提交
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
	if (trans)
		file->private_data = trans;
	else
		ret = -ENOMEM;
	/*printk(KERN_INFO "btrfs_ioctl_trans_start on %p\n", file);*/
out:
	return ret;
}

/*
 * 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;
	int ret = 0;

	trans = file->private_data;
	if (!trans) {
		ret = -EINVAL;
		goto out;
	}
	btrfs_end_transaction(trans, root);
C
Christoph Hellwig 已提交
1233
	file->private_data = NULL;
1234 1235 1236 1237 1238

	mutex_lock(&root->fs_info->trans_mutex);
	root->fs_info->open_ioctl_trans--;
	mutex_unlock(&root->fs_info->trans_mutex);

1239 1240
	mnt_drop_write(file->f_path.mnt);

C
Christoph Hellwig 已提交
1241 1242 1243 1244 1245 1246 1247 1248
out:
	return ret;
}

long btrfs_ioctl(struct file *file, unsigned int
		cmd, unsigned long arg)
{
	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;
1249
	void __user *argp = (void __user *)arg;
C
Christoph Hellwig 已提交
1250 1251

	switch (cmd) {
1252 1253 1254 1255 1256 1257
	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);
C
Christoph Hellwig 已提交
1258
	case BTRFS_IOC_SNAP_CREATE:
1259
		return btrfs_ioctl_snap_create(file, argp, 0);
1260
	case BTRFS_IOC_SUBVOL_CREATE:
1261
		return btrfs_ioctl_snap_create(file, argp, 1);
C
Christoph Hellwig 已提交
1262 1263 1264
	case BTRFS_IOC_DEFRAG:
		return btrfs_ioctl_defrag(file);
	case BTRFS_IOC_RESIZE:
1265
		return btrfs_ioctl_resize(root, argp);
C
Christoph Hellwig 已提交
1266
	case BTRFS_IOC_ADD_DEV:
1267
		return btrfs_ioctl_add_dev(root, argp);
C
Christoph Hellwig 已提交
1268
	case BTRFS_IOC_RM_DEV:
1269
		return btrfs_ioctl_rm_dev(root, argp);
C
Christoph Hellwig 已提交
1270 1271 1272
	case BTRFS_IOC_BALANCE:
		return btrfs_balance(root->fs_info->dev_root);
	case BTRFS_IOC_CLONE:
1273 1274
		return btrfs_ioctl_clone(file, arg, 0, 0, 0);
	case BTRFS_IOC_CLONE_RANGE:
1275
		return btrfs_ioctl_clone_range(file, argp);
C
Christoph Hellwig 已提交
1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286
	case BTRFS_IOC_TRANS_START:
		return btrfs_ioctl_trans_start(file);
	case BTRFS_IOC_TRANS_END:
		return btrfs_ioctl_trans_end(file);
	case BTRFS_IOC_SYNC:
		btrfs_sync_fs(file->f_dentry->d_sb, 1);
		return 0;
	}

	return -ENOTTY;
}