Btrfs: variable block size support
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/mkfs.c b/fs/btrfs/mkfs.c
index dd14ed4..317d20c 100644
--- a/fs/btrfs/mkfs.c
+++ b/fs/btrfs/mkfs.c
@@ -10,19 +10,20 @@
#include "ctree.h"
#include "disk-io.h"
-int mkfs(int fd, u64 num_blocks, u16 blocksize)
+int mkfs(int fd, u64 num_blocks, u32 blocksize)
{
struct btrfs_super_block super;
- struct btrfs_leaf empty_leaf;
+ struct btrfs_leaf *empty_leaf;
struct btrfs_root_item root_item;
struct btrfs_item item;
struct btrfs_extent_item extent_item;
char *block;
int ret;
- u16 itemoff;
+ u32 itemoff;
+ u32 start_block = BTRFS_SUPER_INFO_OFFSET / blocksize;
- btrfs_set_super_blocknr(&super, 16);
- btrfs_set_super_root(&super, 17);
+ btrfs_set_super_blocknr(&super, start_block);
+ btrfs_set_super_root(&super, start_block + 1);
strcpy((char *)(&super.magic), BTRFS_MAGIC);
btrfs_set_super_blocksize(&super, blocksize);
btrfs_set_super_total_blocks(&super, num_blocks);
@@ -32,168 +33,98 @@
memset(block, 0, blocksize);
BUG_ON(sizeof(super) > blocksize);
memcpy(block, &super, sizeof(super));
- ret = pwrite(fd, block, blocksize, BTRFS_SUPER_INFO_OFFSET(blocksize));
+ ret = pwrite(fd, block, blocksize, BTRFS_SUPER_INFO_OFFSET);
BUG_ON(ret != blocksize);
/* create the tree of root objects */
- memset(&empty_leaf, 0, sizeof(empty_leaf));
- btrfs_set_header_parentid(&empty_leaf.header, BTRFS_ROOT_TREE_OBJECTID);
- btrfs_set_header_blocknr(&empty_leaf.header, 17);
- btrfs_set_header_nritems(&empty_leaf.header, 2);
+ empty_leaf = malloc(blocksize);
+ memset(empty_leaf, 0, blocksize);
+ btrfs_set_header_parentid(&empty_leaf->header,
+ BTRFS_ROOT_TREE_OBJECTID);
+ btrfs_set_header_blocknr(&empty_leaf->header, start_block + 1);
+ btrfs_set_header_nritems(&empty_leaf->header, 2);
/* create the items for the root tree */
- btrfs_set_root_blocknr(&root_item, 18);
+ btrfs_set_root_blocknr(&root_item, start_block + 2);
btrfs_set_root_refs(&root_item, 1);
- itemoff = LEAF_DATA_SIZE - sizeof(root_item);
+ itemoff = __BTRFS_LEAF_DATA_SIZE(blocksize) - sizeof(root_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_item_size(&item, sizeof(root_item));
btrfs_set_key_objectid(&item.key, BTRFS_EXTENT_TREE_OBJECTID);
btrfs_set_key_offset(&item.key, 0);
btrfs_set_key_flags(&item.key, 0);
- memcpy(empty_leaf.items, &item, sizeof(item));
- memcpy(empty_leaf.data + itemoff, &root_item, sizeof(root_item));
+ memcpy(empty_leaf->items, &item, sizeof(item));
+ memcpy(btrfs_leaf_data(empty_leaf) + itemoff,
+ &root_item, sizeof(root_item));
- btrfs_set_root_blocknr(&root_item, 19);
+ btrfs_set_root_blocknr(&root_item, start_block + 3);
itemoff = itemoff - sizeof(root_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_key_objectid(&item.key, BTRFS_FS_TREE_OBJECTID);
- memcpy(empty_leaf.items + 1, &item, sizeof(item));
- memcpy(empty_leaf.data + itemoff, &root_item, sizeof(root_item));
- ret = pwrite(fd, &empty_leaf, blocksize, 17 * blocksize);
+ memcpy(empty_leaf->items + 1, &item, sizeof(item));
+ memcpy(btrfs_leaf_data(empty_leaf) + itemoff,
+ &root_item, sizeof(root_item));
+ ret = pwrite(fd, empty_leaf, blocksize, (start_block + 1) * blocksize);
/* create the items for the extent tree */
- btrfs_set_header_parentid(&empty_leaf.header,
+ btrfs_set_header_parentid(&empty_leaf->header,
BTRFS_EXTENT_TREE_OBJECTID);
- btrfs_set_header_blocknr(&empty_leaf.header, 18);
- btrfs_set_header_nritems(&empty_leaf.header, 4);
+ btrfs_set_header_blocknr(&empty_leaf->header, start_block + 2);
+ btrfs_set_header_nritems(&empty_leaf->header, 4);
/* item1, reserve blocks 0-16 */
btrfs_set_key_objectid(&item.key, 0);
- btrfs_set_key_offset(&item.key, 17);
+ btrfs_set_key_offset(&item.key, start_block + 1);
btrfs_set_key_flags(&item.key, 0);
- itemoff = LEAF_DATA_SIZE - sizeof(struct btrfs_extent_item);
+ itemoff = __BTRFS_LEAF_DATA_SIZE(blocksize) -
+ sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_item_size(&item, sizeof(struct btrfs_extent_item));
btrfs_set_extent_refs(&extent_item, 1);
btrfs_set_extent_owner(&extent_item, 0);
- memcpy(empty_leaf.items, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
+ memcpy(empty_leaf->items, &item, sizeof(item));
+ memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
+ &extent_item, btrfs_item_size(&item));
/* item2, give block 17 to the root */
- btrfs_set_key_objectid(&item.key, 17);
+ btrfs_set_key_objectid(&item.key, start_block + 1);
btrfs_set_key_offset(&item.key, 1);
itemoff = itemoff - sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_extent_owner(&extent_item, BTRFS_ROOT_TREE_OBJECTID);
- memcpy(empty_leaf.items + 1, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
+ memcpy(empty_leaf->items + 1, &item, sizeof(item));
+ memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
+ &extent_item, btrfs_item_size(&item));
/* item3, give block 18 to the extent root */
- btrfs_set_key_objectid(&item.key, 18);
+ btrfs_set_key_objectid(&item.key, start_block + 2);
btrfs_set_key_offset(&item.key, 1);
itemoff = itemoff - sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_extent_owner(&extent_item, BTRFS_EXTENT_TREE_OBJECTID);
- memcpy(empty_leaf.items + 2, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
+ memcpy(empty_leaf->items + 2, &item, sizeof(item));
+ memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
+ &extent_item, btrfs_item_size(&item));
/* item4, give block 19 to the FS root */
- btrfs_set_key_objectid(&item.key, 19);
+ btrfs_set_key_objectid(&item.key, start_block + 3);
btrfs_set_key_offset(&item.key, 1);
itemoff = itemoff - sizeof(struct btrfs_extent_item);
btrfs_set_item_offset(&item, itemoff);
btrfs_set_extent_owner(&extent_item, BTRFS_FS_TREE_OBJECTID);
- memcpy(empty_leaf.items + 3, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
- ret = pwrite(fd, &empty_leaf, blocksize, 18 * blocksize);
- if (ret != sizeof(empty_leaf))
+ memcpy(empty_leaf->items + 3, &item, sizeof(item));
+ memcpy(btrfs_leaf_data(empty_leaf) + btrfs_item_offset(&item),
+ &extent_item, btrfs_item_size(&item));
+ ret = pwrite(fd, empty_leaf, blocksize, (start_block + 2) * blocksize);
+ if (ret != blocksize)
return -1;
/* finally create the FS root */
- btrfs_set_header_parentid(&empty_leaf.header, BTRFS_FS_TREE_OBJECTID);
- btrfs_set_header_blocknr(&empty_leaf.header, 19);
- btrfs_set_header_nritems(&empty_leaf.header, 0);
- ret = pwrite(fd, &empty_leaf, blocksize, 19 * blocksize);
- if (ret != sizeof(empty_leaf))
+ btrfs_set_header_parentid(&empty_leaf->header, BTRFS_FS_TREE_OBJECTID);
+ btrfs_set_header_blocknr(&empty_leaf->header, start_block + 3);
+ btrfs_set_header_nritems(&empty_leaf->header, 0);
+ ret = pwrite(fd, empty_leaf, blocksize, (start_block + 3) * blocksize);
+ if (ret != blocksize)
return -1;
return 0;
}
-
-#if 0
-int mkfs(int fd)
-{
- struct btrfs_root_info info[2];
- struct btrfs_leaf empty_leaf;
- struct btrfs_item item;
- struct btrfs_extent_item extent_item;
- int ret;
-
- /* setup the super block area */
- memset(info, 0, sizeof(info));
- btrfs_set_root_blocknr(info, 16);
- btrfs_set_root_objectid(info, 1);
- btrfs_set_root_tree_root(info, 17);
-
- btrfs_set_root_blocknr(info + 1, 16);
- btrfs_set_root_objectid(info + 1, 2);
- btrfs_set_root_tree_root(info + 1, 18);
-
- ret = pwrite(fd, info, sizeof(info),
- BTRFS_SUPER_INFO_OFFSET(BTRFS_BLOCKSIZE));
- if (ret != sizeof(info))
- return -1;
-
- /* create leaves for the tree root and extent root */
- memset(&empty_leaf, 0, sizeof(empty_leaf));
- btrfs_set_header_parentid(&empty_leaf.header, 1);
- btrfs_set_header_blocknr(&empty_leaf.header, 17);
- ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 17 * BTRFS_BLOCKSIZE);
- if (ret != sizeof(empty_leaf))
- return -1;
-
- btrfs_set_header_parentid(&empty_leaf.header, 2);
- btrfs_set_header_blocknr(&empty_leaf.header, 18);
- btrfs_set_header_nritems(&empty_leaf.header, 3);
-
- /* item1, reserve blocks 0-16 */
- btrfs_set_key_objectid(&item.key, 0);
- btrfs_set_key_offset(&item.key, 17);
- btrfs_set_key_flags(&item.key, 0);
- btrfs_set_item_offset(&item, LEAF_DATA_SIZE -
- sizeof(struct btrfs_extent_item));
- btrfs_set_item_size(&item, sizeof(struct btrfs_extent_item));
- btrfs_set_extent_refs(&extent_item, 1);
- btrfs_set_extent_owner(&extent_item, 0);
- memcpy(empty_leaf.items, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
-
- /* item2, give block 17 to the root */
- btrfs_set_key_objectid(&item.key, 17);
- btrfs_set_key_offset(&item.key, 1);
- btrfs_set_item_offset(&item, LEAF_DATA_SIZE -
- sizeof(struct btrfs_extent_item) * 2);
- btrfs_set_extent_owner(&extent_item, 1);
- memcpy(empty_leaf.items + 1, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
-
- /* item3, give block 18 for the extent root */
- btrfs_set_key_objectid(&item.key, 18);
- btrfs_set_key_offset(&item.key, 1);
- btrfs_set_item_offset(&item, LEAF_DATA_SIZE -
- sizeof(struct btrfs_extent_item) * 3);
- btrfs_set_extent_owner(&extent_item, 2);
- memcpy(empty_leaf.items + 2, &item, sizeof(item));
- memcpy(empty_leaf.data + btrfs_item_offset(&item), &extent_item,
- btrfs_item_size(&item));
- ret = pwrite(fd, &empty_leaf, sizeof(empty_leaf), 18 * BTRFS_BLOCKSIZE);
- if (ret != sizeof(empty_leaf))
- return -1;
- return 0;
-}
-#endif