[deliverable/linux.git] / fs / btrfs / disk-io.c

#include <linux/module.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/crypto.h>
#include <linux/scatterlist.h>
#include <linux/swap.h>
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"

static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
{
	struct btrfs_node *node = btrfs_buffer_node(buf);
	if (buf->b_blocknr != btrfs_header_blocknr(&node->header)) {
		BUG();
	}
	if (root->node && btrfs_header_parentid(&node->header) !=
	    btrfs_header_parentid(btrfs_buffer_header(root->node))) {
		BUG();
	}
	return 0;
}

struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr)
{
	return sb_find_get_block(root->fs_info->sb, blocknr);
#if 0
	struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
	int blockbits = root->fs_info->sb->s_blocksize_bits;
	unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
	struct page *page;
	struct buffer_head *bh;
	struct buffer_head *head;
	struct buffer_head *ret = NULL;


	page = find_lock_page(mapping, index);
	if (!page)
		return NULL;

	if (!page_has_buffers(page))
		goto out_unlock;

	head = page_buffers(page);
	bh = head;
	do {
		if (buffer_mapped(bh) && bh->b_blocknr == blocknr) {
			ret = bh;
			get_bh(bh);
			goto out_unlock;
		}
		bh = bh->b_this_page;
	} while (bh != head);
out_unlock:
	unlock_page(page);
	if (ret) {
		touch_buffer(ret);
	}
	page_cache_release(page);
	return ret;
#endif
}

struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
						 u64 blocknr)
{
	return sb_getblk(root->fs_info->sb, blocknr);
#if 0
	struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
	int blockbits = root->fs_info->sb->s_blocksize_bits;
	unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
	struct page *page;
	struct buffer_head *bh;
	struct buffer_head *head;
	struct buffer_head *ret = NULL;
	u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits);

	page = grab_cache_page(mapping, index);
	if (!page)
		return NULL;

	if (!page_has_buffers(page))
		create_empty_buffers(page, root->fs_info->sb->s_blocksize, 0);
	head = page_buffers(page);
	bh = head;
	do {
		if (!buffer_mapped(bh)) {
			bh->b_bdev = root->fs_info->sb->s_bdev;
			bh->b_blocknr = first_block;
			set_buffer_mapped(bh);
		}
		if (bh->b_blocknr == blocknr) {
			ret = bh;
			get_bh(bh);
			goto out_unlock;
		}
		bh = bh->b_this_page;
		first_block++;
	} while (bh != head);
out_unlock:
	unlock_page(page);
	if (ret)
		touch_buffer(ret);
	page_cache_release(page);
	return ret;
#endif
}

static sector_t max_block(struct block_device *bdev)
{
	sector_t retval = ~((sector_t)0);
	loff_t sz = i_size_read(bdev->bd_inode);

	if (sz) {
		unsigned int size = block_size(bdev);
		unsigned int sizebits = blksize_bits(size);
		retval = (sz >> sizebits);
	}
	return retval;
}

static int btree_get_block(struct inode *inode, sector_t iblock,
			   struct buffer_head *bh, int create)
{
	if (iblock >= max_block(inode->i_sb->s_bdev)) {
		if (create)
			return -EIO;

		/*
		 * for reads, we're just trying to fill a partial page.
		 * return a hole, they will have to call get_block again
		 * before they can fill it, and they will get -EIO at that
		 * time
		 */
		return 0;
	}
	bh->b_bdev = inode->i_sb->s_bdev;
	bh->b_blocknr = iblock;
	set_buffer_mapped(bh);
	return 0;
}

int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
		    char *result)
{
	struct scatterlist sg;
	struct crypto_hash *tfm = root->fs_info->hash_tfm;
	struct hash_desc desc;
	int ret;

	desc.tfm = tfm;
	desc.flags = 0;
	sg_init_one(&sg, data, len);
	spin_lock(&root->fs_info->hash_lock);
	ret = crypto_hash_digest(&desc, &sg, 1, result);
	spin_unlock(&root->fs_info->hash_lock);
	if (ret) {
		printk("sha256 digest failed\n");
	}
	return ret;
}
static int csum_tree_block(struct btrfs_root *root, struct buffer_head *bh,
			   int verify)
{
	char result[BTRFS_CSUM_SIZE];
	int ret;
	struct btrfs_node *node;

	return 0;
	ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
			      bh->b_size - BTRFS_CSUM_SIZE, result);
	if (ret)
		return ret;
	if (verify) {
		if (memcmp(bh->b_data, result, BTRFS_CSUM_SIZE)) {
			printk("checksum verify failed on %lu\n",
			       bh->b_blocknr);
			return 1;
		}
	} else {
		node = btrfs_buffer_node(bh);
		memcpy(node->header.csum, result, BTRFS_CSUM_SIZE);
	}
	return 0;
}

static int btree_writepage(struct page *page, struct writeback_control *wbc)
{
#if 0
	struct buffer_head *bh;
	struct btrfs_root *root = btrfs_sb(page->mapping->host->i_sb);
	struct buffer_head *head;
	if (!page_has_buffers(page)) {
		create_empty_buffers(page, root->fs_info->sb->s_blocksize,
					(1 << BH_Dirty)|(1 << BH_Uptodate));
	}
	head = page_buffers(page);
	bh = head;
	do {
		if (buffer_dirty(bh))
			csum_tree_block(root, bh, 0);
		bh = bh->b_this_page;
	} while (bh != head);
#endif
	return block_write_full_page(page, btree_get_block, wbc);
}

static int btree_readpage(struct file * file, struct page * page)
{
	return block_read_full_page(page, btree_get_block);
}

static struct address_space_operations btree_aops = {
	.readpage	= btree_readpage,
	.writepage	= btree_writepage,
	.sync_page	= block_sync_page,
};

struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
{
	return sb_bread(root->fs_info->sb, blocknr);
#if 0
	struct buffer_head *bh = NULL;

	bh = btrfs_find_create_tree_block(root, blocknr);
	if (!bh)
		return bh;
	lock_buffer(bh);
	if (!buffer_uptodate(bh)) {
		get_bh(bh);
		bh->b_end_io = end_buffer_read_sync;
		submit_bh(READ, bh);
		wait_on_buffer(bh);
		if (!buffer_uptodate(bh))
			goto fail;
		csum_tree_block(root, bh, 1);
	} else {
		unlock_buffer(bh);
	}
	if (check_tree_block(root, bh))
		BUG();
	return bh;
fail:
	brelse(bh);
	return NULL;

#endif
}

int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
		     struct buffer_head *buf)
{
	WARN_ON(atomic_read(&buf->b_count) == 0);
	mark_buffer_dirty(buf);
	return 0;
}

int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
		     struct buffer_head *buf)
{
	WARN_ON(atomic_read(&buf->b_count) == 0);
	clear_buffer_dirty(buf);
	return 0;
}

static int __setup_root(int blocksize,
			struct btrfs_root *root,
			struct btrfs_fs_info *fs_info,
			u64 objectid)
{
	root->node = NULL;
	root->commit_root = NULL;
	root->blocksize = blocksize;
	root->ref_cows = 0;
	root->fs_info = fs_info;
	memset(&root->root_key, 0, sizeof(root->root_key));
	memset(&root->root_item, 0, sizeof(root->root_item));
	return 0;
}

static int find_and_setup_root(int blocksize,
			       struct btrfs_root *tree_root,
			       struct btrfs_fs_info *fs_info,
			       u64 objectid,
			       struct btrfs_root *root)
{
	int ret;

	__setup_root(blocksize, root, fs_info, objectid);
	ret = btrfs_find_last_root(tree_root, objectid,
				   &root->root_item, &root->root_key);
	BUG_ON(ret);

	root->node = read_tree_block(root,
				     btrfs_root_blocknr(&root->root_item));
	BUG_ON(!root->node);
	return 0;
}

struct btrfs_root *open_ctree(struct super_block *sb)
{
	struct btrfs_root *root = kmalloc(sizeof(struct btrfs_root),
					  GFP_NOFS);
	struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
						 GFP_NOFS);
	struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
					       GFP_NOFS);
	struct btrfs_root *inode_root = kmalloc(sizeof(struct btrfs_root),
						GFP_NOFS);
	struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
						GFP_NOFS);
	int ret;
	struct btrfs_super_block *disk_super;

	init_bit_radix(&fs_info->pinned_radix);
	init_bit_radix(&fs_info->pending_del_radix);
	sb_set_blocksize(sb, 4096);
	fs_info->running_transaction = NULL;
	fs_info->fs_root = root;
	fs_info->tree_root = tree_root;
	fs_info->extent_root = extent_root;
	fs_info->inode_root = inode_root;
	fs_info->last_inode_alloc = 0;
	fs_info->last_inode_alloc_dirid = 0;
	fs_info->sb = sb;
	fs_info->btree_inode = NULL;
#if 0
	fs_info->btree_inode = new_inode(sb);
	fs_info->btree_inode->i_ino = 1;
	fs_info->btree_inode->i_nlink = 1;
	fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
	insert_inode_hash(fs_info->btree_inode);
	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
#endif
	fs_info->hash_tfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC);
	spin_lock_init(&fs_info->hash_lock);
	if (!fs_info->hash_tfm || IS_ERR(fs_info->hash_tfm)) {
		printk("failed to allocate sha256 hash\n");
		return NULL;
	}
	mutex_init(&fs_info->trans_mutex);
	mutex_init(&fs_info->fs_mutex);
	memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
	memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));

	__setup_root(sb->s_blocksize, tree_root,
		     fs_info, BTRFS_ROOT_TREE_OBJECTID);
	fs_info->sb_buffer = read_tree_block(tree_root,
					     BTRFS_SUPER_INFO_OFFSET /
					     sb->s_blocksize);

	if (!fs_info->sb_buffer) {
printk("failed2\n");
		return NULL;
	}
	disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
	if (!btrfs_super_root(disk_super)) {
		return NULL;
	}
	fs_info->disk_super = disk_super;
	tree_root->node = read_tree_block(tree_root,
					  btrfs_super_root(disk_super));
	BUG_ON(!tree_root->node);

	mutex_lock(&fs_info->fs_mutex);
	ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
				  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
	BUG_ON(ret);

	ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
				  BTRFS_INODE_MAP_OBJECTID, inode_root);
	BUG_ON(ret);

	ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
				  BTRFS_FS_TREE_OBJECTID, root);
	mutex_unlock(&fs_info->fs_mutex);
	BUG_ON(ret);
	root->commit_root = root->node;
	get_bh(root->node);
	root->ref_cows = 1;
	root->fs_info->generation = root->root_key.offset + 1;
	return root;
}

int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
		      *root)
{
	struct buffer_head *bh = root->fs_info->sb_buffer;

	btrfs_set_super_root(root->fs_info->disk_super,
			     root->fs_info->tree_root->node->b_blocknr);
	lock_buffer(bh);
	WARN_ON(atomic_read(&bh->b_count) < 1);
	clear_buffer_dirty(bh);
	csum_tree_block(root, bh, 0);
	bh->b_end_io = end_buffer_write_sync;
	get_bh(bh);
	submit_bh(WRITE, bh);
	wait_on_buffer(bh);
	if (!buffer_uptodate(bh)) {
		WARN_ON(1);
		return -EIO;
	}
	return 0;
}

int close_ctree(struct btrfs_root *root)
{
	int ret;
	struct btrfs_trans_handle *trans;

	mutex_lock(&root->fs_info->fs_mutex);
	trans = btrfs_start_transaction(root, 1);
	btrfs_commit_transaction(trans, root);
	/* run commit again to  drop the original snapshot */
	trans = btrfs_start_transaction(root, 1);
	btrfs_commit_transaction(trans, root);
	ret = btrfs_write_and_wait_transaction(NULL, root);
	BUG_ON(ret);
	write_ctree_super(NULL, root);
	mutex_unlock(&root->fs_info->fs_mutex);

	if (root->node)
		btrfs_block_release(root, root->node);
	if (root->fs_info->extent_root->node)
		btrfs_block_release(root->fs_info->extent_root,
				    root->fs_info->extent_root->node);
	if (root->fs_info->inode_root->node)
		btrfs_block_release(root->fs_info->inode_root,
				    root->fs_info->inode_root->node);
	if (root->fs_info->tree_root->node)
		btrfs_block_release(root->fs_info->tree_root,
				    root->fs_info->tree_root->node);
	btrfs_block_release(root, root->commit_root);
	btrfs_block_release(root, root->fs_info->sb_buffer);
	crypto_free_hash(root->fs_info->hash_tfm);
	// truncate_inode_pages(root->fs_info->btree_inode->i_mapping, 0);
	// iput(root->fs_info->btree_inode);
	kfree(root->fs_info->extent_root);
	kfree(root->fs_info->inode_root);
	kfree(root->fs_info->tree_root);
	kfree(root->fs_info);
	kfree(root);
	return 0;
}

void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf)
{
	// brelse(buf);
}
Commit	Line	Data
e20d96d6 CM	1	#include <linux/module.h>
e20d96d6 CM	2	#include <linux/fs.h>
d98237b3	3	#include <linux/blkdev.h>
87cbda5c CM	4	#include <linux/crypto.h>
87cbda5c CM	5	#include <linux/scatterlist.h>
22b0ebda	6	#include <linux/swap.h>
eb60ceac CM	7	#include "ctree.h"
eb60ceac CM	8	#include "disk-io.h"
e089f05c	9	#include "transaction.h"
eb60ceac	10
e20d96d6	11	static int check_tree_block(struct btrfs_root root, struct buffer_head buf)
eb60ceac	12	{
e20d96d6	13	struct btrfs_node *node = btrfs_buffer_node(buf);
d98237b3	14	if (buf->b_blocknr != btrfs_header_blocknr(&node->header)) {
9a8dd150	15	BUG();
d98237b3	16	}
e20d96d6	17	if (root->node && btrfs_header_parentid(&node->header) !=
df2ce34c	18	btrfs_header_parentid(btrfs_buffer_header(root->node))) {
7f5c1516	19	BUG();
df2ce34c	20	}
9a8dd150	21	return 0;
eb60ceac CM	22	}
eb60ceac CM	23
d98237b3 CM	24	struct buffer_head btrfs_find_tree_block(struct btrfs_root root, u64 blocknr)
d98237b3 CM	25	{
2c90e5d6 CM	26	return sb_find_get_block(root->fs_info->sb, blocknr);
2c90e5d6 CM	27	#if 0
d98237b3 CM	28	struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
	29	int blockbits = root->fs_info->sb->s_blocksize_bits;
	30	unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
	31	struct page *page;
	32	struct buffer_head *bh;
	33	struct buffer_head *head;
	34	struct buffer_head *ret = NULL;
	35
2c90e5d6	36
d98237b3 CM	37	page = find_lock_page(mapping, index);
	38	if (!page)
	39	return NULL;
	40
	41	if (!page_has_buffers(page))
	42	goto out_unlock;
	43
	44	head = page_buffers(page);
	45	bh = head;
	46	do {
	47	if (buffer_mapped(bh) && bh->b_blocknr == blocknr) {
	48	ret = bh;
	49	get_bh(bh);
	50	goto out_unlock;
	51	}
	52	bh = bh->b_this_page;
	53	} while (bh != head);
	54	out_unlock:
	55	unlock_page(page);
d6025579	56	if (ret) {
22b0ebda	57	touch_buffer(ret);
d6025579	58	}
d98237b3 CM	59	page_cache_release(page);
d98237b3 CM	60	return ret;
2c90e5d6	61	#endif
d98237b3 CM	62	}
	63
	64	struct buffer_head btrfs_find_create_tree_block(struct btrfs_root root,
	65	u64 blocknr)
	66	{
2c90e5d6 CM	67	return sb_getblk(root->fs_info->sb, blocknr);
2c90e5d6 CM	68	#if 0
d98237b3 CM	69	struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
	70	int blockbits = root->fs_info->sb->s_blocksize_bits;
	71	unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
	72	struct page *page;
	73	struct buffer_head *bh;
	74	struct buffer_head *head;
	75	struct buffer_head *ret = NULL;
	76	u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits);
22b0ebda	77
d98237b3 CM	78	page = grab_cache_page(mapping, index);
	79	if (!page)
	80	return NULL;
	81
d98237b3 CM	82	if (!page_has_buffers(page))
	83	create_empty_buffers(page, root->fs_info->sb->s_blocksize, 0);
	84	head = page_buffers(page);
	85	bh = head;
	86	do {
	87	if (!buffer_mapped(bh)) {
	88	bh->b_bdev = root->fs_info->sb->s_bdev;
	89	bh->b_blocknr = first_block;
	90	set_buffer_mapped(bh);
	91	}
	92	if (bh->b_blocknr == blocknr) {
	93	ret = bh;
	94	get_bh(bh);
	95	goto out_unlock;
	96	}
	97	bh = bh->b_this_page;
	98	first_block++;
	99	} while (bh != head);
	100	out_unlock:
	101	unlock_page(page);
22b0ebda CM	102	if (ret)
22b0ebda CM	103	touch_buffer(ret);
d98237b3 CM	104	page_cache_release(page);
d98237b3 CM	105	return ret;
2c90e5d6	106	#endif
d98237b3 CM	107	}
	108
	109	static sector_t max_block(struct block_device *bdev)
	110	{
	111	sector_t retval = ~((sector_t)0);
	112	loff_t sz = i_size_read(bdev->bd_inode);
	113
	114	if (sz) {
	115	unsigned int size = block_size(bdev);
	116	unsigned int sizebits = blksize_bits(size);
	117	retval = (sz >> sizebits);
	118	}
	119	return retval;
	120	}
	121
	122	static int btree_get_block(struct inode *inode, sector_t iblock,
	123	struct buffer_head *bh, int create)
	124	{
	125	if (iblock >= max_block(inode->i_sb->s_bdev)) {
	126	if (create)
	127	return -EIO;
	128
	129	/*
	130	* for reads, we're just trying to fill a partial page.
	131	* return a hole, they will have to call get_block again
	132	* before they can fill it, and they will get -EIO at that
	133	* time
	134	*/
	135	return 0;
	136	}
	137	bh->b_bdev = inode->i_sb->s_bdev;
	138	bh->b_blocknr = iblock;
	139	set_buffer_mapped(bh);
	140	return 0;
	141	}
	142
f254e52c CM	143	int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
f254e52c CM	144	char *result)
87cbda5c	145	{
87cbda5c CM	146	struct scatterlist sg;
	147	struct crypto_hash *tfm = root->fs_info->hash_tfm;
	148	struct hash_desc desc;
	149	int ret;
87cbda5c CM	150
	151	desc.tfm = tfm;
	152	desc.flags = 0;
f254e52c	153	sg_init_one(&sg, data, len);
87cbda5c	154	spin_lock(&root->fs_info->hash_lock);
22b0ebda	155	ret = crypto_hash_digest(&desc, &sg, 1, result);
87cbda5c CM	156	spin_unlock(&root->fs_info->hash_lock);
	157	if (ret) {
	158	printk("sha256 digest failed\n");
	159	}
f254e52c CM	160	return ret;
	161	}
	162	static int csum_tree_block(struct btrfs_root root, struct buffer_head bh,
	163	int verify)
	164	{
	165	char result[BTRFS_CSUM_SIZE];
	166	int ret;
	167	struct btrfs_node *node;
	168
22b0ebda	169	return 0;
f254e52c CM	170	ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
	171	bh->b_size - BTRFS_CSUM_SIZE, result);
	172	if (ret)
	173	return ret;
87cbda5c	174	if (verify) {
f254e52c CM	175	if (memcmp(bh->b_data, result, BTRFS_CSUM_SIZE)) {
	176	printk("checksum verify failed on %lu\n",
	177	bh->b_blocknr);
	178	return 1;
	179	}
	180	} else {
	181	node = btrfs_buffer_node(bh);
22b0ebda	182	memcpy(node->header.csum, result, BTRFS_CSUM_SIZE);
f254e52c	183	}
87cbda5c CM	184	return 0;
	185	}
	186
d98237b3	187	static int btree_writepage(struct page page, struct writeback_control wbc)
ed2ff2cb	188	{
22b0ebda	189	#if 0
87cbda5c CM	190	struct buffer_head *bh;
	191	struct btrfs_root *root = btrfs_sb(page->mapping->host->i_sb);
	192	struct buffer_head *head;
87cbda5c CM	193	if (!page_has_buffers(page)) {
	194	create_empty_buffers(page, root->fs_info->sb->s_blocksize,
	195	(1 << BH_Dirty)\|(1 << BH_Uptodate));
	196	}
	197	head = page_buffers(page);
	198	bh = head;
	199	do {
	200	if (buffer_dirty(bh))
	201	csum_tree_block(root, bh, 0);
	202	bh = bh->b_this_page;
	203	} while (bh != head);
22b0ebda	204	#endif
d98237b3	205	return block_write_full_page(page, btree_get_block, wbc);
ed2ff2cb CM	206	}
ed2ff2cb CM	207
d98237b3	208	static int btree_readpage(struct file * file, struct page * page)
eb60ceac	209	{
d98237b3	210	return block_read_full_page(page, btree_get_block);
eb60ceac CM	211	}
eb60ceac CM	212
d98237b3 CM	213	static struct address_space_operations btree_aops = {
	214	.readpage = btree_readpage,
	215	.writepage = btree_writepage,
	216	.sync_page = block_sync_page,
	217	};
	218
e20d96d6	219	struct buffer_head read_tree_block(struct btrfs_root root, u64 blocknr)
eb60ceac	220	{
2c90e5d6 CM	221	return sb_bread(root->fs_info->sb, blocknr);
2c90e5d6 CM	222	#if 0
d98237b3	223	struct buffer_head *bh = NULL;
eb60ceac	224
d98237b3 CM	225	bh = btrfs_find_create_tree_block(root, blocknr);
	226	if (!bh)
	227	return bh;
	228	lock_buffer(bh);
	229	if (!buffer_uptodate(bh)) {
	230	get_bh(bh);
	231	bh->b_end_io = end_buffer_read_sync;
	232	submit_bh(READ, bh);
	233	wait_on_buffer(bh);
	234	if (!buffer_uptodate(bh))
	235	goto fail;
87cbda5c	236	csum_tree_block(root, bh, 1);
d98237b3 CM	237	} else {
	238	unlock_buffer(bh);
	239	}
	240	if (check_tree_block(root, bh))
cfaa7295	241	BUG();
d98237b3 CM	242	return bh;
	243	fail:
	244	brelse(bh);
	245	return NULL;
	246
2c90e5d6	247	#endif
eb60ceac CM	248	}
eb60ceac CM	249
e089f05c	250	int dirty_tree_block(struct btrfs_trans_handle trans, struct btrfs_root root,
e20d96d6	251	struct buffer_head *buf)
ed2ff2cb	252	{
d6025579	253	WARN_ON(atomic_read(&buf->b_count) == 0);
e20d96d6	254	mark_buffer_dirty(buf);
ed2ff2cb CM	255	return 0;
	256	}
	257
e089f05c	258	int clean_tree_block(struct btrfs_trans_handle trans, struct btrfs_root root,
e20d96d6	259	struct buffer_head *buf)
ed2ff2cb	260	{
d6025579	261	WARN_ON(atomic_read(&buf->b_count) == 0);
e20d96d6	262	clear_buffer_dirty(buf);
ed2ff2cb CM	263	return 0;
	264	}
	265
2c90e5d6	266	static int __setup_root(int blocksize,
9f5fae2f CM	267	struct btrfs_root *root,
9f5fae2f CM	268	struct btrfs_fs_info *fs_info,
e20d96d6	269	u64 objectid)
d97e63b6	270	{
cfaa7295	271	root->node = NULL;
a28ec197	272	root->commit_root = NULL;
2c90e5d6	273	root->blocksize = blocksize;
123abc88	274	root->ref_cows = 0;
9f5fae2f	275	root->fs_info = fs_info;
3768f368 CM	276	memset(&root->root_key, 0, sizeof(root->root_key));
	277	memset(&root->root_item, 0, sizeof(root->root_item));
	278	return 0;
	279	}
	280
2c90e5d6	281	static int find_and_setup_root(int blocksize,
9f5fae2f CM	282	struct btrfs_root *tree_root,
	283	struct btrfs_fs_info *fs_info,
	284	u64 objectid,
e20d96d6	285	struct btrfs_root *root)
3768f368 CM	286	{
	287	int ret;
	288
2c90e5d6	289	__setup_root(blocksize, root, fs_info, objectid);
3768f368 CM	290	ret = btrfs_find_last_root(tree_root, objectid,
	291	&root->root_item, &root->root_key);
	292	BUG_ON(ret);
	293
	294	root->node = read_tree_block(root,
	295	btrfs_root_blocknr(&root->root_item));
3768f368	296	BUG_ON(!root->node);
d97e63b6 CM	297	return 0;
	298	}
	299
2c90e5d6	300	struct btrfs_root open_ctree(struct super_block sb)
2e635a27	301	{
e20d96d6 CM	302	struct btrfs_root *root = kmalloc(sizeof(struct btrfs_root),
	303	GFP_NOFS);
	304	struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
	305	GFP_NOFS);
	306	struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
	307	GFP_NOFS);
	308	struct btrfs_root *inode_root = kmalloc(sizeof(struct btrfs_root),
	309	GFP_NOFS);
	310	struct btrfs_fs_info fs_info = kmalloc(sizeof(fs_info),
	311	GFP_NOFS);
eb60ceac	312	int ret;
2c90e5d6	313	struct btrfs_super_block *disk_super;
eb60ceac	314
8ef97622 CM	315	init_bit_radix(&fs_info->pinned_radix);
8ef97622 CM	316	init_bit_radix(&fs_info->pending_del_radix);
2c90e5d6	317	sb_set_blocksize(sb, 4096);
9f5fae2f CM	318	fs_info->running_transaction = NULL;
	319	fs_info->fs_root = root;
	320	fs_info->tree_root = tree_root;
	321	fs_info->extent_root = extent_root;
	322	fs_info->inode_root = inode_root;
	323	fs_info->last_inode_alloc = 0;
	324	fs_info->last_inode_alloc_dirid = 0;
e20d96d6	325	fs_info->sb = sb;
2c90e5d6 CM	326	fs_info->btree_inode = NULL;
2c90e5d6 CM	327	#if 0
d98237b3 CM	328	fs_info->btree_inode = new_inode(sb);
d98237b3 CM	329	fs_info->btree_inode->i_ino = 1;
2c90e5d6	330	fs_info->btree_inode->i_nlink = 1;
d98237b3 CM	331	fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
d98237b3 CM	332	fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
22b0ebda	333	insert_inode_hash(fs_info->btree_inode);
d98237b3	334	mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
2c90e5d6	335	#endif
87cbda5c	336	fs_info->hash_tfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC);
30ae8467	337	spin_lock_init(&fs_info->hash_lock);
30ae8467	338	if (!fs_info->hash_tfm \|\| IS_ERR(fs_info->hash_tfm)) {
87cbda5c CM	339	printk("failed to allocate sha256 hash\n");
	340	return NULL;
	341	}
79154b1b	342	mutex_init(&fs_info->trans_mutex);
d561c025	343	mutex_init(&fs_info->fs_mutex);
9f5fae2f CM	344	memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
9f5fae2f CM	345	memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));
3768f368	346
2c90e5d6 CM	347	__setup_root(sb->s_blocksize, tree_root,
	348	fs_info, BTRFS_ROOT_TREE_OBJECTID);
	349	fs_info->sb_buffer = read_tree_block(tree_root,
	350	BTRFS_SUPER_INFO_OFFSET /
	351	sb->s_blocksize);
d98237b3	352
87cbda5c CM	353	if (!fs_info->sb_buffer) {
87cbda5c CM	354	printk("failed2\n");
d98237b3	355	return NULL;
87cbda5c	356	}
d98237b3	357	disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
2c90e5d6 CM	358	if (!btrfs_super_root(disk_super)) {
	359	return NULL;
	360	}
d98237b3	361	fs_info->disk_super = disk_super;
e20d96d6 CM	362	tree_root->node = read_tree_block(tree_root,
e20d96d6 CM	363	btrfs_super_root(disk_super));
3768f368 CM	364	BUG_ON(!tree_root->node);
3768f368 CM	365
2c90e5d6 CM	366	mutex_lock(&fs_info->fs_mutex);
2c90e5d6 CM	367	ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
e20d96d6	368	BTRFS_EXTENT_TREE_OBJECTID, extent_root);
3768f368 CM	369	BUG_ON(ret);
3768f368 CM	370
2c90e5d6	371	ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
e20d96d6	372	BTRFS_INODE_MAP_OBJECTID, inode_root);
9f5fae2f CM	373	BUG_ON(ret);
9f5fae2f CM	374
2c90e5d6	375	ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
e20d96d6	376	BTRFS_FS_TREE_OBJECTID, root);
2c90e5d6	377	mutex_unlock(&fs_info->fs_mutex);
3768f368	378	BUG_ON(ret);
a28ec197	379	root->commit_root = root->node;
e20d96d6	380	get_bh(root->node);
3768f368	381	root->ref_cows = 1;
293ffd5f	382	root->fs_info->generation = root->root_key.offset + 1;
eb60ceac CM	383	return root;
	384	}
	385
e089f05c	386	int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
79154b1b	387	*root)
eb60ceac	388	{
d5719762	389	struct buffer_head *bh = root->fs_info->sb_buffer;
2c90e5d6	390
d5719762 CM	391	btrfs_set_super_root(root->fs_info->disk_super,
	392	root->fs_info->tree_root->node->b_blocknr);
	393	lock_buffer(bh);
2c90e5d6	394	WARN_ON(atomic_read(&bh->b_count) < 1);
d5719762	395	clear_buffer_dirty(bh);
87cbda5c	396	csum_tree_block(root, bh, 0);
d5719762 CM	397	bh->b_end_io = end_buffer_write_sync;
	398	get_bh(bh);
	399	submit_bh(WRITE, bh);
	400	wait_on_buffer(bh);
	401	if (!buffer_uptodate(bh)) {
	402	WARN_ON(1);
	403	return -EIO;
cfaa7295 CM	404	}
	405	return 0;
	406	}
	407
e20d96d6	408	int close_ctree(struct btrfs_root *root)
cfaa7295	409	{
3768f368	410	int ret;
e089f05c CM	411	struct btrfs_trans_handle *trans;
e089f05c CM	412
2c90e5d6	413	mutex_lock(&root->fs_info->fs_mutex);
79154b1b CM	414	trans = btrfs_start_transaction(root, 1);
	415	btrfs_commit_transaction(trans, root);
	416	/* run commit again to drop the original snapshot */
	417	trans = btrfs_start_transaction(root, 1);
	418	btrfs_commit_transaction(trans, root);
	419	ret = btrfs_write_and_wait_transaction(NULL, root);
3768f368	420	BUG_ON(ret);
79154b1b	421	write_ctree_super(NULL, root);
2c90e5d6	422	mutex_unlock(&root->fs_info->fs_mutex);
ed2ff2cb	423
cfaa7295	424	if (root->node)
234b63a0	425	btrfs_block_release(root, root->node);
9f5fae2f CM	426	if (root->fs_info->extent_root->node)
	427	btrfs_block_release(root->fs_info->extent_root,
	428	root->fs_info->extent_root->node);
	429	if (root->fs_info->inode_root->node)
	430	btrfs_block_release(root->fs_info->inode_root,
	431	root->fs_info->inode_root->node);
	432	if (root->fs_info->tree_root->node)
	433	btrfs_block_release(root->fs_info->tree_root,
	434	root->fs_info->tree_root->node);
234b63a0	435	btrfs_block_release(root, root->commit_root);
e20d96d6	436	btrfs_block_release(root, root->fs_info->sb_buffer);
87cbda5c	437	crypto_free_hash(root->fs_info->hash_tfm);
2c90e5d6 CM	438	// truncate_inode_pages(root->fs_info->btree_inode->i_mapping, 0);
2c90e5d6 CM	439	// iput(root->fs_info->btree_inode);
e20d96d6 CM	440	kfree(root->fs_info->extent_root);
	441	kfree(root->fs_info->inode_root);
	442	kfree(root->fs_info->tree_root);
	443	kfree(root->fs_info);
	444	kfree(root);
eb60ceac CM	445	return 0;
	446	}
	447
e20d96d6	448	void btrfs_block_release(struct btrfs_root root, struct buffer_head buf)
eb60ceac	449	{
2c90e5d6	450	// brelse(buf);
eb60ceac CM	451	}
eb60ceac CM	452