[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)
{
	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;
}

struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
						 u64 blocknr)
{
	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;
}

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)
{
	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;

}

int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
		     struct buffer_head *buf)
{
	mark_buffer_dirty(buf);
	return 0;
}

int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
		     struct buffer_head *buf)
{
	clear_buffer_dirty(buf);
	return 0;
}

static int __setup_root(struct btrfs_super_block *super,
			struct btrfs_root *root,
			struct btrfs_fs_info *fs_info,
			u64 objectid)
{
	root->node = NULL;
	root->commit_root = NULL;
	root->blocksize = btrfs_super_blocksize(super);
	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(struct btrfs_super_block *super,
			       struct btrfs_root *tree_root,
			       struct btrfs_fs_info *fs_info,
			       u64 objectid,
			       struct btrfs_root *root)
{
	int ret;

	__setup_root(super, 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 buffer_head *sb_buffer,
			      struct btrfs_super_block *disk_super)
{
	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;

	if (!btrfs_super_root(disk_super)) {
		return NULL;
	}
	init_bit_radix(&fs_info->pinned_radix);
	init_bit_radix(&fs_info->pending_del_radix);
	sb_set_blocksize(sb, sb_buffer->b_size);
	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->disk_super = disk_super;
	fs_info->sb = sb;
	fs_info->btree_inode = new_inode(sb);
	fs_info->btree_inode->i_ino = 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);
	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(disk_super, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);

	fs_info->sb_buffer = read_tree_block(tree_root, sb_buffer->b_blocknr);

	if (!fs_info->sb_buffer) {
printk("failed2\n");
		return NULL;
	}
	brelse(sb_buffer);
	sb_buffer = NULL;
	disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
	fs_info->disk_super = disk_super;

	tree_root->node = read_tree_block(tree_root,
					  btrfs_super_root(disk_super));
	BUG_ON(!tree_root->node);

	ret = find_and_setup_root(disk_super, tree_root, fs_info,
				  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
	BUG_ON(ret);

	ret = find_and_setup_root(disk_super, tree_root, fs_info,
				  BTRFS_INODE_MAP_OBJECTID, inode_root);
	BUG_ON(ret);

	ret = find_and_setup_root(disk_super, tree_root, fs_info,
				  BTRFS_FS_TREE_OBJECTID, root);
	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);
	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;

	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);

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