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add mkfs.c

master
Chris Mason 2007-02-20 16:41:09 -05:00 committed by David Woodhouse
parent c12e4863d2
commit 828ba34028
1 changed files with 69 additions and 0 deletions
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mkfs.c 100644
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@ -0,0 +1,69 @@
#define _XOPEN_SOURCE 500
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include "kerncompat.h"
#include "radix-tree.h"
#include "ctree.h"
#include "disk-io.h"
int mkfs(int fd)
{
struct ctree_root_info info[2];
struct leaf empty_leaf;
struct item item;
struct extent_item extent_item;
int ret;
memset(info, 0, sizeof(info));
info[0].blocknr = 16;
info[0].objectid = 1;
info[0].tree_root = 17;
info[0].alloc_extent.blocknr = 0;
info[0].alloc_extent.num_blocks = 20;
/* 0-17 are used (inclusive) */
info[0].alloc_extent.num_used = 18;
info[1].blocknr = 16;
info[1].objectid = 2;
info[1].tree_root = 64;
info[1].alloc_extent.blocknr = 64;
info[1].alloc_extent.num_blocks = 8;
info[1].alloc_extent.num_used = 1;
ret = pwrite(fd, info, sizeof(info),
CTREE_SUPER_INFO_OFFSET(CTREE_BLOCKSIZE));
if (ret != sizeof(info))
return -1;
memset(&empty_leaf, 0, sizeof(empty_leaf));
empty_leaf.header.parentid = 1;
empty_leaf.header.blocknr = 17;
ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 17 * CTREE_BLOCKSIZE);
if (ret != sizeof(empty_leaf))
return -1;
empty_leaf.header.parentid = 2;
empty_leaf.header.blocknr = 64;
empty_leaf.header.nritems = 2;
item.key.objectid = 0;
item.key.offset = 64;
item.key.flags = 0;
item.offset = LEAF_DATA_SIZE - sizeof(struct extent_item);
item.size = sizeof(struct extent_item);
extent_item.refs = 1;
extent_item.owner = 1;
memcpy(empty_leaf.items, &item, sizeof(item));
memcpy(empty_leaf.data + item.offset, &extent_item, item.size);
item.key.objectid = 64;
item.key.offset = 64;
item.offset = LEAF_DATA_SIZE - sizeof(struct extent_item) * 2;
extent_item.owner = 2;
memcpy(empty_leaf.items + 1, &item, sizeof(item));
memcpy(empty_leaf.data + item.offset, &extent_item, item.size);
ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 64 * CTREE_BLOCKSIZE);
if (ret != sizeof(empty_leaf))
return -1;
return 0;
}