diff options
Diffstat (limited to 'utils.c')
| -rw-r--r-- | utils.c | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/utils.c b/utils.c new file mode 100644 index 00000000..31d19e81 --- /dev/null +++ b/utils.c @@ -0,0 +1,236 @@ +/* + * 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[4] = { + [0] = 0, + [1] = BTRFS_ROOT_TREE_OBJECTID, + [2] = BTRFS_EXTENT_TREE_OBJECTID, + [3] = BTRFS_FS_TREE_OBJECTID, +}; + +int make_btrfs(int fd, u64 blocks[4], 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; + int i; + int ret; + u32 itemoff; + u32 nritems = 0; + u64 hash; + u64 first_free; + u64 ref_gen; + u64 ref_root; + + 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]); + strcpy((char *)(&super.magic), BTRFS_MAGIC); + btrfs_set_super_generation(&super, 1); + btrfs_set_super_root(&super, blocks[1]); + btrfs_set_super_total_bytes(&super, num_bytes); + btrfs_set_super_bytes_used(&super, first_free + 3 * 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); + + buf = malloc(sizeof(*buf) + max(sectorsize, leafsize)); + + 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); + + /* create the tree of root objects */ + memset(buf->data, 0, leafsize); + btrfs_set_header_bytenr(buf, blocks[1]); + btrfs_set_header_nritems(buf, 2); + 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[3]); + 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)); + 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 = 0; i < 4; i++) { + if (blocks[i] < first_free) { + BUG_ON(i > 0); + continue; + } + /* 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); + + /* finally create the FS root */ + btrfs_set_header_bytenr(buf, blocks[3]); + btrfs_set_header_owner(buf, BTRFS_FS_TREE_OBJECTID); + btrfs_set_header_nritems(buf, 0); + ret = pwrite(fd, buf->data, leafsize, blocks[3]); + BUG_ON(ret != leafsize); + + 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; +} |