btrfs-progs/utils.c

/*
 * 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.
 */

#define _XOPEN_SOURCE 600
#define __USE_XOPEN2K
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <uuid/uuid.h>
#include <fcntl.h>
#include <unistd.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "crc32c.h"
#include "utils.h"
static u64 reference_root_table[6] = {
	[1] =	BTRFS_ROOT_TREE_OBJECTID,
	[2] =	BTRFS_EXTENT_TREE_OBJECTID,
	[3] =	BTRFS_CHUNK_TREE_OBJECTID,
	[4] =	BTRFS_DEV_TREE_OBJECTID,
	[5] =	BTRFS_FS_TREE_OBJECTID,
};

int make_btrfs(int fd, char *device_name,
	       u64 blocks[6], u64 num_bytes, u32 nodesize,
	       u32 leafsize, u32 sectorsize, u32 stripesize)
{
	struct btrfs_super_block super;
	struct extent_buffer *buf;
	struct btrfs_root_item root_item;
	struct btrfs_disk_key disk_key;
	struct btrfs_extent_ref *extent_ref;
	struct btrfs_extent_item *extent_item;
	struct btrfs_inode_item *inode_item;
	struct btrfs_chunk *chunk;
	struct btrfs_dev_item *dev_item;
	struct btrfs_dev_extent *dev_extent;
	u8 *ptr;
	int i;
	int ret;
	u32 itemoff;
	u32 nritems = 0;
	u64 hash;
	u64 first_free;
	u64 ref_gen;
	u64 ref_root;
	u32 array_size;
	u32 item_size;

	first_free = BTRFS_SUPER_INFO_OFFSET + sectorsize * 2 - 1;
	first_free &= ~((u64)sectorsize - 1);

	num_bytes = (num_bytes / sectorsize) * sectorsize;
	uuid_generate(super.fsid);
	btrfs_set_super_bytenr(&super, blocks[0]);
	strncpy((char *)&super.magic, BTRFS_MAGIC, sizeof(super.magic));
	btrfs_set_super_generation(&super, 1);
	btrfs_set_super_root(&super, blocks[1]);
	btrfs_set_super_chunk_root(&super, blocks[3]);
	btrfs_set_super_total_bytes(&super, num_bytes);
	btrfs_set_super_bytes_used(&super, first_free + 5 * leafsize);
	btrfs_set_super_root_dir(&super, 0);
	btrfs_set_super_sectorsize(&super, sectorsize);
	btrfs_set_super_leafsize(&super, leafsize);
	btrfs_set_super_nodesize(&super, nodesize);
	btrfs_set_super_stripesize(&super, stripesize);
	btrfs_set_super_root_level(&super, 0);
	btrfs_set_super_chunk_root_level(&super, 0);
	btrfs_set_super_sys_array_size(&super, 0);

	buf = malloc(sizeof(*buf) + max(sectorsize, leafsize));

	/* create the tree of root objects */
	memset(buf->data, 0, leafsize);
	btrfs_set_header_bytenr(buf, blocks[1]);
	btrfs_set_header_nritems(buf, 3);
	btrfs_set_header_generation(buf, 1);
	btrfs_set_header_owner(buf, BTRFS_ROOT_TREE_OBJECTID);
	write_extent_buffer(buf, super.fsid, (unsigned long)
			    btrfs_header_fsid(buf), BTRFS_FSID_SIZE);

	/* create the items for the root tree */
	memset(&root_item, 0, sizeof(root_item));
	inode_item = &root_item.inode;
	btrfs_set_stack_inode_generation(inode_item, 1);
	btrfs_set_stack_inode_size(inode_item, 3);
	btrfs_set_stack_inode_nlink(inode_item, 1);
	btrfs_set_stack_inode_nblocks(inode_item, 1);
	btrfs_set_stack_inode_mode(inode_item, S_IFDIR | 0755);
	btrfs_set_root_refs(&root_item, 1);
	btrfs_set_root_used(&root_item, leafsize);

	memset(&disk_key, 0, sizeof(disk_key));
	btrfs_set_disk_key_type(&disk_key, BTRFS_ROOT_ITEM_KEY);
	btrfs_set_disk_key_offset(&disk_key, 0);

	itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize) - sizeof(root_item);
	btrfs_set_root_bytenr(&root_item, blocks[2]);
	btrfs_set_disk_key_objectid(&disk_key, BTRFS_EXTENT_TREE_OBJECTID);
	btrfs_set_item_key(buf, &disk_key, 0);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, 0), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf, 0), sizeof(root_item));
	write_extent_buffer(buf, &root_item, btrfs_item_ptr_offset(buf, 0),
			    sizeof(root_item));

	itemoff = itemoff - sizeof(root_item);
	btrfs_set_root_bytenr(&root_item, blocks[5]);
	btrfs_set_disk_key_objectid(&disk_key, BTRFS_FS_TREE_OBJECTID);
	btrfs_set_item_key(buf, &disk_key, 1);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, 1), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf, 1), sizeof(root_item));
	write_extent_buffer(buf, &root_item, btrfs_item_ptr_offset(buf, 1),
			    sizeof(root_item));

	itemoff = itemoff - sizeof(root_item);
	btrfs_set_root_bytenr(&root_item, blocks[4]);
	btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_TREE_OBJECTID);
	btrfs_set_item_key(buf, &disk_key, 2);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, 2), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf, 2), sizeof(root_item));
	write_extent_buffer(buf, &root_item, btrfs_item_ptr_offset(buf, 2),
			    sizeof(root_item));

	ret = pwrite(fd, buf->data, leafsize, blocks[1]);
	BUG_ON(ret != leafsize);

	/* create the items for the extent tree */
	itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize) -
		  sizeof(struct btrfs_extent_item);
	btrfs_set_disk_key_objectid(&disk_key, 0);
	btrfs_set_disk_key_offset(&disk_key, first_free);
	btrfs_set_disk_key_type(&disk_key, BTRFS_EXTENT_ITEM_KEY);
	btrfs_set_item_key(buf, &disk_key, nritems);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, nritems), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf,  nritems),
			    sizeof(struct btrfs_extent_item));
	extent_item = btrfs_item_ptr(buf, nritems, struct btrfs_extent_item);
	btrfs_set_extent_refs(buf, extent_item, 1);
	nritems++;
	for (i = 1; i < 6; i++) {
		BUG_ON(blocks[i] < first_free);
		BUG_ON(blocks[i] < blocks[i - 1]);

		/* create extent item */
		itemoff = itemoff - sizeof(struct btrfs_extent_item);
		btrfs_set_disk_key_objectid(&disk_key, blocks[i]);
		btrfs_set_disk_key_offset(&disk_key, leafsize);
		btrfs_set_disk_key_type(&disk_key, BTRFS_EXTENT_ITEM_KEY);
		btrfs_set_item_key(buf, &disk_key, nritems);
		btrfs_set_item_offset(buf, btrfs_item_nr(buf, nritems),
				      itemoff);
		btrfs_set_item_size(buf, btrfs_item_nr(buf, nritems),
				    sizeof(struct btrfs_extent_item));
		extent_item = btrfs_item_ptr(buf, nritems,
					     struct btrfs_extent_item);
		btrfs_set_extent_refs(buf, extent_item, 1);
		nritems++;

		/* create extent ref */
		ref_root = reference_root_table[i];
		if (ref_root == BTRFS_FS_TREE_OBJECTID)
			ref_gen = 1;
		else
			ref_gen = 0;

		hash = btrfs_hash_extent_ref(ref_root, ref_gen, 0, 0);
		itemoff = itemoff - sizeof(struct btrfs_extent_ref);
		btrfs_set_disk_key_objectid(&disk_key, blocks[i]);
		btrfs_set_disk_key_offset(&disk_key, hash);
		btrfs_set_disk_key_type(&disk_key, BTRFS_EXTENT_REF_KEY);
		btrfs_set_item_key(buf, &disk_key, nritems);
		btrfs_set_item_offset(buf, btrfs_item_nr(buf, nritems),
				      itemoff);
		btrfs_set_item_size(buf, btrfs_item_nr(buf, nritems),
				    sizeof(struct btrfs_extent_ref));
		extent_ref = btrfs_item_ptr(buf, nritems,
					     struct btrfs_extent_ref);
		btrfs_set_ref_root(buf, extent_ref, ref_root);
		btrfs_set_ref_generation(buf, extent_ref, ref_gen);
		btrfs_set_ref_objectid(buf, extent_ref, 0);
		btrfs_set_ref_offset(buf, extent_ref, 0);
		nritems++;
	}
	btrfs_set_header_bytenr(buf, blocks[2]);
	btrfs_set_header_owner(buf, BTRFS_EXTENT_TREE_OBJECTID);
	btrfs_set_header_nritems(buf, nritems);
	ret = pwrite(fd, buf->data, leafsize, blocks[2]);
	BUG_ON(ret != leafsize);

	/* create the chunk tree */
	nritems = 0;
	item_size = btrfs_chunk_item_size(1);
	itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize) - item_size;

	/* first we have chunk 0 */
	btrfs_set_disk_key_objectid(&disk_key, 0);
	btrfs_set_disk_key_offset(&disk_key, BTRFS_MKFS_SYSTEM_GROUP_SIZE);
	btrfs_set_disk_key_type(&disk_key, BTRFS_CHUNK_ITEM_KEY);
	btrfs_set_item_key(buf, &disk_key, nritems);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, nritems), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf,  nritems), item_size);

	chunk = btrfs_item_ptr(buf, nritems, struct btrfs_chunk);
	btrfs_set_chunk_owner(buf, chunk, BTRFS_EXTENT_TREE_OBJECTID);
	btrfs_set_chunk_stripe_len(buf, chunk, 64 * 1024);
	btrfs_set_chunk_type(buf, chunk, BTRFS_BLOCK_GROUP_SYSTEM);
	btrfs_set_chunk_io_align(buf, chunk, sectorsize);
	btrfs_set_chunk_io_width(buf, chunk, sectorsize);
	btrfs_set_chunk_sector_size(buf, chunk, sectorsize);
	btrfs_set_chunk_num_stripes(buf, chunk, 1);
	btrfs_set_stripe_devid_nr(buf, chunk, 0, 1);
	btrfs_set_stripe_offset_nr(buf, chunk, 0, 0);

	/* copy the key for the chunk to the system array */
	ptr = super.sys_chunk_array;
	array_size = sizeof(disk_key);

	memcpy(ptr, &disk_key, sizeof(disk_key));
	ptr += sizeof(disk_key);

	/* copy the chunk to the system array */
	read_extent_buffer(buf, ptr, (unsigned long)chunk, item_size);
	array_size += item_size;
	ptr += item_size;

	/* then device 1 (there is no device 0) */
	nritems++;
	item_size = sizeof(*dev_item) + strlen(device_name);
	itemoff = itemoff - item_size;
	btrfs_set_disk_key_objectid(&disk_key, BTRFS_DEV_ITEMS_OBJECTID);
	btrfs_set_disk_key_offset(&disk_key, 1);
	btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_ITEM_KEY);
	btrfs_set_item_key(buf, &disk_key, nritems);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, nritems), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf, nritems), item_size);

	dev_item = btrfs_item_ptr(buf, nritems, struct btrfs_dev_item);
	btrfs_set_device_id(buf, dev_item, 1);
	btrfs_set_device_total_bytes(buf, dev_item, num_bytes);
	btrfs_set_device_bytes_used(buf, dev_item,
				    BTRFS_MKFS_SYSTEM_GROUP_SIZE);
	btrfs_set_device_io_align(buf, dev_item, sectorsize);
	btrfs_set_device_io_width(buf, dev_item, sectorsize);
	btrfs_set_device_sector_size(buf, dev_item, sectorsize);
	btrfs_set_device_rdev(buf, dev_item, 0);
	btrfs_set_device_type(buf, dev_item, 0);
	btrfs_set_device_partition(buf, dev_item, 0);
	btrfs_set_device_name_len(buf, dev_item, strlen(device_name));
	nritems++;

	memset_extent_buffer(buf, 0, (unsigned long)btrfs_device_uuid(dev_item),
			     BTRFS_DEV_UUID_SIZE);
	write_extent_buffer(buf, device_name,
			    (unsigned long)btrfs_device_name(dev_item),
			    strlen(device_name));

	/* copy the device item and key into the system array */
	memcpy(ptr, &disk_key, sizeof(disk_key));
	ptr += sizeof(disk_key);
	array_size += sizeof(disk_key);

	read_extent_buffer(buf, ptr, (unsigned long)dev_item, item_size);
	array_size += item_size;
	ptr += item_size;

	btrfs_set_super_sys_array_size(&super, array_size);

	btrfs_set_header_bytenr(buf, blocks[3]);
	btrfs_set_header_owner(buf, BTRFS_CHUNK_TREE_OBJECTID);
	btrfs_set_header_nritems(buf, nritems);
	ret = pwrite(fd, buf->data, leafsize, blocks[3]);

	/* create the device tree */
	nritems = 0;
	itemoff = __BTRFS_LEAF_DATA_SIZE(leafsize) -
		sizeof(struct btrfs_dev_extent);

	btrfs_set_disk_key_objectid(&disk_key, 1);
	btrfs_set_disk_key_offset(&disk_key, 0);
	btrfs_set_disk_key_type(&disk_key, BTRFS_DEV_EXTENT_KEY);
	btrfs_set_item_key(buf, &disk_key, nritems);
	btrfs_set_item_offset(buf, btrfs_item_nr(buf, nritems), itemoff);
	btrfs_set_item_size(buf, btrfs_item_nr(buf,  nritems),
			    sizeof(struct btrfs_dev_extent));
	dev_extent = btrfs_item_ptr(buf, nritems, struct btrfs_dev_extent);
	btrfs_set_dev_extent_owner(buf, dev_extent, 0);
	btrfs_set_dev_extent_length(buf, dev_extent,
				    BTRFS_MKFS_SYSTEM_GROUP_SIZE);
	nritems++;

	btrfs_set_header_bytenr(buf, blocks[4]);
	btrfs_set_header_owner(buf, BTRFS_DEV_TREE_OBJECTID);
	btrfs_set_header_nritems(buf, nritems);
	ret = pwrite(fd, buf->data, leafsize, blocks[4]);

	/* finally create the FS root */
	btrfs_set_header_bytenr(buf, blocks[5]);
	btrfs_set_header_owner(buf, BTRFS_FS_TREE_OBJECTID);
	btrfs_set_header_nritems(buf, 0);
	ret = pwrite(fd, buf->data, leafsize, blocks[5]);
	BUG_ON(ret != leafsize);

	/* and write out the super block */
	BUG_ON(sizeof(super) > sectorsize);
	memset(buf->data, 0, sectorsize);
	memcpy(buf->data, &super, sizeof(super));
	ret = pwrite(fd, buf->data, sectorsize, blocks[0]);
	BUG_ON(ret != sectorsize);


	free(buf);
	return 0;
}

int btrfs_make_root_dir(struct btrfs_trans_handle *trans,
			struct btrfs_root *root, u64 objectid)
{
	int ret;
	struct btrfs_inode_item inode_item;

	memset(&inode_item, 0, sizeof(inode_item));
	btrfs_set_stack_inode_generation(&inode_item, trans->transid);
	btrfs_set_stack_inode_size(&inode_item, 0);
	btrfs_set_stack_inode_nlink(&inode_item, 1);
	btrfs_set_stack_inode_nblocks(&inode_item, 1);
	btrfs_set_stack_inode_mode(&inode_item, S_IFDIR | 0555);

	if (root->fs_info->tree_root == root)
		btrfs_set_super_root_dir(&root->fs_info->super_copy, objectid);

	ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
	if (ret)
		goto error;

	ret = btrfs_insert_inode_ref(trans, root, "..", 2, objectid, objectid);
	if (ret)
		goto error;

	btrfs_set_root_dirid(&root->root_item, objectid);
	ret = 0;
error:
	return ret;
}