[linux-2.6-block.git] / fs / btrfs / disk-io.c

#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"

static int allocated_blocks = 0;
int cache_max = 10000;

static int check_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
{
	if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
		BUG();
	if (root->node && btrfs_header_parentid(&buf->node.header) !=
	    btrfs_header_parentid(&root->node->node.header))
		BUG();
	return 0;
}

static int free_some_buffers(struct btrfs_root *root)
{
	struct list_head *node, *next;
	struct btrfs_buffer *b;
	if (root->cache_size < cache_max)
		return 0;
	list_for_each_safe(node, next, &root->cache) {
		b = list_entry(node, struct btrfs_buffer, cache);
		if (b->count == 1) {
			BUG_ON(!list_empty(&b->dirty));
			list_del_init(&b->cache);
			btrfs_block_release(root, b);
			if (root->cache_size < cache_max)
				break;
		}
	}
	return 0;
}

struct btrfs_buffer *alloc_tree_block(struct btrfs_root *root, u64 blocknr)
{
	struct btrfs_buffer *buf;
	int ret;

	buf = malloc(sizeof(struct btrfs_buffer) + root->blocksize);
	if (!buf)
		return buf;
	allocated_blocks++;
	buf->blocknr = blocknr;
	buf->count = 2;
	INIT_LIST_HEAD(&buf->dirty);
	free_some_buffers(root);
	radix_tree_preload(GFP_KERNEL);
	ret = radix_tree_insert(&root->cache_radix, blocknr, buf);
	radix_tree_preload_end();
	list_add_tail(&buf->cache, &root->cache);
	root->cache_size++;
	if (ret) {
		free(buf);
		return NULL;
	}
	return buf;
}

struct btrfs_buffer *find_tree_block(struct btrfs_root *root, u64 blocknr)
{
	struct btrfs_buffer *buf;
	buf = radix_tree_lookup(&root->cache_radix, blocknr);
	if (buf) {
		buf->count++;
	} else {
		buf = alloc_tree_block(root, blocknr);
		if (!buf) {
			BUG();
			return NULL;
		}
	}
	return buf;
}

struct btrfs_buffer *read_tree_block(struct btrfs_root *root, u64 blocknr)
{
	loff_t offset = blocknr * root->blocksize;
	struct btrfs_buffer *buf;
	int ret;

	buf = radix_tree_lookup(&root->cache_radix, blocknr);
	if (buf) {
		buf->count++;
	} else {
		buf = alloc_tree_block(root, blocknr);
		if (!buf)
			return NULL;
		ret = pread(root->fp, &buf->node, root->blocksize, offset);
		if (ret != root->blocksize) {
			free(buf);
			return NULL;
		}
	}
	if (check_tree_block(root, buf))
		BUG();
	return buf;
}

int dirty_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
{
	if (!list_empty(&buf->dirty))
		return 0;
	list_add_tail(&buf->dirty, &root->trans);
	buf->count++;
	return 0;
}

int clean_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
{
	if (!list_empty(&buf->dirty)) {
		list_del_init(&buf->dirty);
		btrfs_block_release(root, buf);
	}
	return 0;
}

int write_tree_block(struct btrfs_root *root, struct btrfs_buffer *buf)
{
	u64 blocknr = buf->blocknr;
	loff_t offset = blocknr * root->blocksize;
	int ret;

	if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
		BUG();
	ret = pwrite(root->fp, &buf->node, root->blocksize, offset);
	if (ret != root->blocksize)
		return ret;
	return 0;
}

static int __commit_transaction(struct btrfs_root *root)
{
	struct btrfs_buffer *b;
	int ret = 0;
	int wret;
	while(!list_empty(&root->trans)) {
		b = list_entry(root->trans.next, struct btrfs_buffer, dirty);
		list_del_init(&b->dirty);
		wret = write_tree_block(root, b);
		if (wret)
			ret = wret;
		btrfs_block_release(root, b);
	}
	return ret;
}

static int commit_extent_and_tree_roots(struct btrfs_root *tree_root,
					struct btrfs_root *extent_root)
{
	int ret;
	u64 old_extent_block;

	while(1) {
		old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
		if (old_extent_block == extent_root->node->blocknr)
			break;
		btrfs_set_root_blocknr(&extent_root->root_item,
				       extent_root->node->blocknr);
		ret = btrfs_update_root(tree_root,
					&extent_root->root_key,
					&extent_root->root_item);
		BUG_ON(ret);
	}
	__commit_transaction(extent_root);
	__commit_transaction(tree_root);
	return 0;
}

int btrfs_commit_transaction(struct btrfs_root *root,
			     struct btrfs_super_block *s)
{
	int ret = 0;
	struct btrfs_buffer *snap = root->commit_root;
	struct btrfs_key snap_key;

	ret = __commit_transaction(root);
	BUG_ON(ret);

	if (root->commit_root == root->node)
		return 0;

	memcpy(&snap_key, &root->root_key, sizeof(snap_key));
	root->root_key.offset++;

	btrfs_set_root_blocknr(&root->root_item, root->node->blocknr);
	ret = btrfs_insert_root(root->tree_root, &root->root_key,
				&root->root_item);
	BUG_ON(ret);

	ret = commit_extent_and_tree_roots(root->tree_root, root->extent_root);
	BUG_ON(ret);

        write_ctree_super(root, s);
	btrfs_finish_extent_commit(root->extent_root);
	btrfs_finish_extent_commit(root->tree_root);

	root->commit_root = root->node;
	root->node->count++;
	ret = btrfs_drop_snapshot(root, snap);
	BUG_ON(ret);

	ret = btrfs_del_root(root->tree_root, &snap_key);
	BUG_ON(ret);

	return ret;
}

static int __setup_root(struct btrfs_super_block *super,
			struct btrfs_root *root, u64 objectid, int fp)
{
	INIT_LIST_HEAD(&root->trans);
	INIT_LIST_HEAD(&root->cache);
	root->cache_size = 0;
	root->fp = fp;
	root->node = NULL;
	root->commit_root = NULL;
	root->blocksize = btrfs_super_blocksize(super);
	root->ref_cows = 0;
	memset(&root->current_insert, 0, sizeof(root->current_insert));
	memset(&root->last_insert, 0, sizeof(root->last_insert));
	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, u64 objectid,
			       struct btrfs_root *root, int fp)
{
	int ret;

	__setup_root(super, root, objectid, fp);
	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(char *filename, struct btrfs_super_block *super)
{
	struct btrfs_root *root = malloc(sizeof(struct btrfs_root));
	struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
	struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
	int fp;
	int ret;

	root->extent_root = extent_root;
	root->tree_root = tree_root;

	extent_root->extent_root = extent_root;
	extent_root->tree_root = tree_root;

	tree_root->extent_root = extent_root;
	tree_root->tree_root = tree_root;

	fp = open(filename, O_CREAT | O_RDWR, 0600);
	if (fp < 0) {
		free(root);
		return NULL;
	}
	INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
	INIT_RADIX_TREE(&root->pinned_radix, GFP_KERNEL);
	INIT_RADIX_TREE(&extent_root->pinned_radix, GFP_KERNEL);
	INIT_RADIX_TREE(&extent_root->cache_radix, GFP_KERNEL);
	INIT_RADIX_TREE(&tree_root->pinned_radix, GFP_KERNEL);
	INIT_RADIX_TREE(&tree_root->cache_radix, GFP_KERNEL);

	ret = pread(fp, super, sizeof(struct btrfs_super_block),
		     BTRFS_SUPER_INFO_OFFSET);
	if (ret == 0 || btrfs_super_root(super) == 0) {
		printf("making new FS!\n");
		ret = mkfs(fp, 0, 1024);
		if (ret)
			return NULL;
		ret = pread(fp, super, sizeof(struct btrfs_super_block),
			     BTRFS_SUPER_INFO_OFFSET);
		if (ret != sizeof(struct btrfs_super_block))
			return NULL;
	}
	BUG_ON(ret < 0);

	__setup_root(super, tree_root, BTRFS_ROOT_TREE_OBJECTID, fp);
	tree_root->node = read_tree_block(tree_root, btrfs_super_root(super));
	BUG_ON(!tree_root->node);

	ret = find_and_setup_root(super, tree_root, BTRFS_EXTENT_TREE_OBJECTID,
				  extent_root, fp);
	BUG_ON(ret);

	ret = find_and_setup_root(super, tree_root, BTRFS_FS_TREE_OBJECTID,
				  root, fp);
	BUG_ON(ret);

	root->commit_root = root->node;
	root->node->count++;
	root->ref_cows = 1;
	return root;
}

int write_ctree_super(struct btrfs_root *root, struct btrfs_super_block *s)
{
	int ret;
	btrfs_set_super_root(s, root->tree_root->node->blocknr);
	ret = pwrite(root->fp, s, sizeof(*s),
		     BTRFS_SUPER_INFO_OFFSET);
	if (ret != sizeof(*s)) {
		fprintf(stderr, "failed to write new super block err %d\n", ret);
		return ret;
	}
	return 0;
}

static int drop_cache(struct btrfs_root *root)
{
	while(!list_empty(&root->cache)) {
		struct btrfs_buffer *b = list_entry(root->cache.next,
						   struct btrfs_buffer, cache);
		list_del_init(&b->cache);
		btrfs_block_release(root, b);
	}
	return 0;
}
int close_ctree(struct btrfs_root *root, struct btrfs_super_block *s)
{
	int ret;
	btrfs_commit_transaction(root, s);
	ret = commit_extent_and_tree_roots(root->tree_root, root->extent_root);
	BUG_ON(ret);
	write_ctree_super(root, s);
	drop_cache(root->extent_root);
	drop_cache(root->tree_root);
	drop_cache(root);
	BUG_ON(!list_empty(&root->trans));
	BUG_ON(!list_empty(&root->extent_root->trans));
	BUG_ON(!list_empty(&root->tree_root->trans));

	close(root->fp);
	if (root->node)
		btrfs_block_release(root, root->node);
	if (root->extent_root->node)
		btrfs_block_release(root->extent_root, root->extent_root->node);
	if (root->tree_root->node)
		btrfs_block_release(root->tree_root, root->tree_root->node);
	btrfs_block_release(root, root->commit_root);
	free(root);
	printf("on close %d blocks are allocated\n", allocated_blocks);
	return 0;
}

void btrfs_block_release(struct btrfs_root *root, struct btrfs_buffer *buf)
{
	buf->count--;
	if (buf->count < 0)
		BUG();
	if (buf->count == 0) {
		BUG_ON(!list_empty(&buf->cache));
		BUG_ON(!list_empty(&buf->dirty));
		if (!radix_tree_lookup(&root->cache_radix, buf->blocknr))
			BUG();
		radix_tree_delete(&root->cache_radix, buf->blocknr);
		memset(buf, 0, sizeof(*buf));
		free(buf);
		BUG_ON(allocated_blocks == 0);
		allocated_blocks--;
		BUG_ON(root->cache_size == 0);
		root->cache_size--;
	}
}
Commit	Line	Data
eb60ceac CM	1	#define _XOPEN_SOURCE 500
	2	#include <stdio.h>
	3	#include <stdlib.h>
	4	#include <sys/types.h>
	5	#include <sys/stat.h>
	6	#include <fcntl.h>
	7	#include <unistd.h>
	8	#include "kerncompat.h"
	9	#include "radix-tree.h"
	10	#include "ctree.h"
	11	#include "disk-io.h"
	12
	13	static int allocated_blocks = 0;
ed2ff2cb	14	int cache_max = 10000;
eb60ceac	15
234b63a0	16	static int check_tree_block(struct btrfs_root root, struct btrfs_buffer buf)
eb60ceac	17	{
7518a238	18	if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
9a8dd150	19	BUG();
7518a238 CM	20	if (root->node && btrfs_header_parentid(&buf->node.header) !=
7518a238 CM	21	btrfs_header_parentid(&root->node->node.header))
9a8dd150 CM	22	BUG();
9a8dd150 CM	23	return 0;
eb60ceac CM	24	}
eb60ceac CM	25
234b63a0	26	static int free_some_buffers(struct btrfs_root *root)
ed2ff2cb CM	27	{
ed2ff2cb CM	28	struct list_head node, next;
234b63a0	29	struct btrfs_buffer *b;
ed2ff2cb CM	30	if (root->cache_size < cache_max)
	31	return 0;
	32	list_for_each_safe(node, next, &root->cache) {
234b63a0	33	b = list_entry(node, struct btrfs_buffer, cache);
ed2ff2cb CM	34	if (b->count == 1) {
	35	BUG_ON(!list_empty(&b->dirty));
	36	list_del_init(&b->cache);
234b63a0	37	btrfs_block_release(root, b);
ed2ff2cb	38	if (root->cache_size < cache_max)
77ce6846	39	break;
ed2ff2cb CM	40	}
	41	}
	42	return 0;
	43	}
	44
234b63a0	45	struct btrfs_buffer alloc_tree_block(struct btrfs_root root, u64 blocknr)
eb60ceac	46	{
234b63a0	47	struct btrfs_buffer *buf;
eb60ceac	48	int ret;
123abc88 CM	49
123abc88 CM	50	buf = malloc(sizeof(struct btrfs_buffer) + root->blocksize);
eb60ceac CM	51	if (!buf)
	52	return buf;
	53	allocated_blocks++;
	54	buf->blocknr = blocknr;
ed2ff2cb CM	55	buf->count = 2;
	56	INIT_LIST_HEAD(&buf->dirty);
	57	free_some_buffers(root);
eb60ceac CM	58	radix_tree_preload(GFP_KERNEL);
	59	ret = radix_tree_insert(&root->cache_radix, blocknr, buf);
	60	radix_tree_preload_end();
ed2ff2cb CM	61	list_add_tail(&buf->cache, &root->cache);
ed2ff2cb CM	62	root->cache_size++;
eb60ceac CM	63	if (ret) {
	64	free(buf);
	65	return NULL;
	66	}
	67	return buf;
	68	}
	69
234b63a0	70	struct btrfs_buffer find_tree_block(struct btrfs_root root, u64 blocknr)
eb60ceac	71	{
234b63a0	72	struct btrfs_buffer *buf;
9a8dd150 CM	73	buf = radix_tree_lookup(&root->cache_radix, blocknr);
	74	if (buf) {
	75	buf->count++;
	76	} else {
	77	buf = alloc_tree_block(root, blocknr);
	78	if (!buf) {
	79	BUG();
	80	return NULL;
	81	}
eb60ceac	82	}
eb60ceac CM	83	return buf;
	84	}
	85
234b63a0	86	struct btrfs_buffer read_tree_block(struct btrfs_root root, u64 blocknr)
eb60ceac	87	{
123abc88	88	loff_t offset = blocknr * root->blocksize;
234b63a0	89	struct btrfs_buffer *buf;
eb60ceac CM	90	int ret;
	91
	92	buf = radix_tree_lookup(&root->cache_radix, blocknr);
	93	if (buf) {
	94	buf->count++;
9a8dd150 CM	95	} else {
	96	buf = alloc_tree_block(root, blocknr);
	97	if (!buf)
	98	return NULL;
123abc88 CM	99	ret = pread(root->fp, &buf->node, root->blocksize, offset);
123abc88 CM	100	if (ret != root->blocksize) {
9a8dd150 CM	101	free(buf);
	102	return NULL;
	103	}
eb60ceac	104	}
9a8dd150	105	if (check_tree_block(root, buf))
cfaa7295	106	BUG();
eb60ceac CM	107	return buf;
	108	}
	109
234b63a0	110	int dirty_tree_block(struct btrfs_root root, struct btrfs_buffer buf)
ed2ff2cb CM	111	{
	112	if (!list_empty(&buf->dirty))
	113	return 0;
	114	list_add_tail(&buf->dirty, &root->trans);
	115	buf->count++;
	116	return 0;
	117	}
	118
234b63a0	119	int clean_tree_block(struct btrfs_root root, struct btrfs_buffer buf)
ed2ff2cb CM	120	{
	121	if (!list_empty(&buf->dirty)) {
	122	list_del_init(&buf->dirty);
234b63a0	123	btrfs_block_release(root, buf);
ed2ff2cb CM	124	}
	125	return 0;
	126	}
	127
234b63a0	128	int write_tree_block(struct btrfs_root root, struct btrfs_buffer buf)
eb60ceac CM	129	{
eb60ceac CM	130	u64 blocknr = buf->blocknr;
123abc88	131	loff_t offset = blocknr * root->blocksize;
eb60ceac CM	132	int ret;
eb60ceac CM	133
7518a238	134	if (buf->blocknr != btrfs_header_blocknr(&buf->node.header))
eb60ceac	135	BUG();
123abc88 CM	136	ret = pwrite(root->fp, &buf->node, root->blocksize, offset);
123abc88 CM	137	if (ret != root->blocksize)
eb60ceac	138	return ret;
eb60ceac CM	139	return 0;
	140	}
	141
234b63a0	142	static int __commit_transaction(struct btrfs_root *root)
ed2ff2cb	143	{
234b63a0	144	struct btrfs_buffer *b;
ed2ff2cb CM	145	int ret = 0;
	146	int wret;
	147	while(!list_empty(&root->trans)) {
234b63a0	148	b = list_entry(root->trans.next, struct btrfs_buffer, dirty);
ed2ff2cb CM	149	list_del_init(&b->dirty);
	150	wret = write_tree_block(root, b);
	151	if (wret)
	152	ret = wret;
234b63a0	153	btrfs_block_release(root, b);
ed2ff2cb CM	154	}
	155	return ret;
	156	}
	157
3768f368 CM	158	static int commit_extent_and_tree_roots(struct btrfs_root *tree_root,
	159	struct btrfs_root *extent_root)
	160	{
	161	int ret;
	162	u64 old_extent_block;
	163
	164	while(1) {
	165	old_extent_block = btrfs_root_blocknr(&extent_root->root_item);
	166	if (old_extent_block == extent_root->node->blocknr)
	167	break;
	168	btrfs_set_root_blocknr(&extent_root->root_item,
	169	extent_root->node->blocknr);
	170	ret = btrfs_update_root(tree_root,
	171	&extent_root->root_key,
	172	&extent_root->root_item);
	173	BUG_ON(ret);
	174	}
	175	__commit_transaction(extent_root);
	176	__commit_transaction(tree_root);
	177	return 0;
	178	}
	179
234b63a0 CM	180	int btrfs_commit_transaction(struct btrfs_root *root,
234b63a0 CM	181	struct btrfs_super_block *s)
ed2ff2cb	182	{
a28ec197	183	int ret = 0;
3768f368 CM	184	struct btrfs_buffer *snap = root->commit_root;
3768f368 CM	185	struct btrfs_key snap_key;
a28ec197	186
ed2ff2cb	187	ret = __commit_transaction(root);
ed2ff2cb	188	BUG_ON(ret);
3768f368 CM	189
	190	if (root->commit_root == root->node)
	191	return 0;
	192
	193	memcpy(&snap_key, &root->root_key, sizeof(snap_key));
	194	root->root_key.offset++;
	195
	196	btrfs_set_root_blocknr(&root->root_item, root->node->blocknr);
	197	ret = btrfs_insert_root(root->tree_root, &root->root_key,
	198	&root->root_item);
	199	BUG_ON(ret);
	200
	201	ret = commit_extent_and_tree_roots(root->tree_root, root->extent_root);
	202	BUG_ON(ret);
	203
a28ec197	204	write_ctree_super(root, s);
3768f368 CM	205	btrfs_finish_extent_commit(root->extent_root);
	206	btrfs_finish_extent_commit(root->tree_root);
	207
	208	root->commit_root = root->node;
	209	root->node->count++;
	210	ret = btrfs_drop_snapshot(root, snap);
	211	BUG_ON(ret);
	212
	213	ret = btrfs_del_root(root->tree_root, &snap_key);
	214	BUG_ON(ret);
	215
ed2ff2cb CM	216	return ret;
	217	}
	218
123abc88 CM	219	static int __setup_root(struct btrfs_super_block *super,
123abc88 CM	220	struct btrfs_root *root, u64 objectid, int fp)
d97e63b6	221	{
ed2ff2cb CM	222	INIT_LIST_HEAD(&root->trans);
ed2ff2cb CM	223	INIT_LIST_HEAD(&root->cache);
a28ec197	224	root->cache_size = 0;
d97e63b6	225	root->fp = fp;
cfaa7295	226	root->node = NULL;
a28ec197	227	root->commit_root = NULL;
123abc88 CM	228	root->blocksize = btrfs_super_blocksize(super);
123abc88 CM	229	root->ref_cows = 0;
a28ec197	230	memset(&root->current_insert, 0, sizeof(root->current_insert));
0579da42	231	memset(&root->last_insert, 0, sizeof(root->last_insert));
3768f368 CM	232	memset(&root->root_key, 0, sizeof(root->root_key));
	233	memset(&root->root_item, 0, sizeof(root->root_item));
	234	return 0;
	235	}
	236
123abc88 CM	237	static int find_and_setup_root(struct btrfs_super_block *super,
	238	struct btrfs_root *tree_root, u64 objectid,
	239	struct btrfs_root *root, int fp)
3768f368 CM	240	{
	241	int ret;
	242
123abc88	243	__setup_root(super, root, objectid, fp);
3768f368 CM	244	ret = btrfs_find_last_root(tree_root, objectid,
	245	&root->root_item, &root->root_key);
	246	BUG_ON(ret);
	247
	248	root->node = read_tree_block(root,
	249	btrfs_root_blocknr(&root->root_item));
3768f368	250	BUG_ON(!root->node);
d97e63b6 CM	251	return 0;
	252	}
	253
234b63a0	254	struct btrfs_root open_ctree(char filename, struct btrfs_super_block *super)
eb60ceac	255	{
234b63a0 CM	256	struct btrfs_root *root = malloc(sizeof(struct btrfs_root));
234b63a0 CM	257	struct btrfs_root *extent_root = malloc(sizeof(struct btrfs_root));
3768f368	258	struct btrfs_root *tree_root = malloc(sizeof(struct btrfs_root));
eb60ceac	259	int fp;
eb60ceac CM	260	int ret;
eb60ceac CM	261
3768f368 CM	262	root->extent_root = extent_root;
	263	root->tree_root = tree_root;
	264
	265	extent_root->extent_root = extent_root;
	266	extent_root->tree_root = tree_root;
	267
	268	tree_root->extent_root = extent_root;
	269	tree_root->tree_root = tree_root;
	270
c673024a	271	fp = open(filename, O_CREAT \| O_RDWR, 0600);
eb60ceac CM	272	if (fp < 0) {
	273	free(root);
	274	return NULL;
	275	}
9a8dd150	276	INIT_RADIX_TREE(&root->cache_radix, GFP_KERNEL);
a28ec197 CM	277	INIT_RADIX_TREE(&root->pinned_radix, GFP_KERNEL);
a28ec197 CM	278	INIT_RADIX_TREE(&extent_root->pinned_radix, GFP_KERNEL);
9a8dd150	279	INIT_RADIX_TREE(&extent_root->cache_radix, GFP_KERNEL);
3768f368 CM	280	INIT_RADIX_TREE(&tree_root->pinned_radix, GFP_KERNEL);
	281	INIT_RADIX_TREE(&tree_root->cache_radix, GFP_KERNEL);
	282
234b63a0	283	ret = pread(fp, super, sizeof(struct btrfs_super_block),
123abc88	284	BTRFS_SUPER_INFO_OFFSET);
3768f368	285	if (ret == 0 \|\| btrfs_super_root(super) == 0) {
5c680ed6	286	printf("making new FS!\n");
123abc88	287	ret = mkfs(fp, 0, 1024);
d97e63b6 CM	288	if (ret)
d97e63b6 CM	289	return NULL;
234b63a0	290	ret = pread(fp, super, sizeof(struct btrfs_super_block),
123abc88	291	BTRFS_SUPER_INFO_OFFSET);
234b63a0	292	if (ret != sizeof(struct btrfs_super_block))
d97e63b6 CM	293	return NULL;
	294	}
	295	BUG_ON(ret < 0);
3768f368	296
123abc88	297	__setup_root(super, tree_root, BTRFS_ROOT_TREE_OBJECTID, fp);
3768f368 CM	298	tree_root->node = read_tree_block(tree_root, btrfs_super_root(super));
	299	BUG_ON(!tree_root->node);
	300
123abc88	301	ret = find_and_setup_root(super, tree_root, BTRFS_EXTENT_TREE_OBJECTID,
3768f368 CM	302	extent_root, fp);
	303	BUG_ON(ret);
	304
123abc88	305	ret = find_and_setup_root(super, tree_root, BTRFS_FS_TREE_OBJECTID,
3768f368 CM	306	root, fp);
	307	BUG_ON(ret);
	308
a28ec197 CM	309	root->commit_root = root->node;
a28ec197 CM	310	root->node->count++;
3768f368	311	root->ref_cows = 1;
eb60ceac CM	312	return root;
	313	}
	314
234b63a0	315	int write_ctree_super(struct btrfs_root root, struct btrfs_super_block s)
eb60ceac CM	316	{
eb60ceac CM	317	int ret;
3768f368	318	btrfs_set_super_root(s, root->tree_root->node->blocknr);
234b63a0	319	ret = pwrite(root->fp, s, sizeof(*s),
123abc88	320	BTRFS_SUPER_INFO_OFFSET);
cfaa7295 CM	321	if (ret != sizeof(*s)) {
cfaa7295 CM	322	fprintf(stderr, "failed to write new super block err %d\n", ret);
eb60ceac	323	return ret;
cfaa7295 CM	324	}
	325	return 0;
	326	}
	327
234b63a0	328	static int drop_cache(struct btrfs_root *root)
ed2ff2cb CM	329	{
ed2ff2cb CM	330	while(!list_empty(&root->cache)) {
234b63a0 CM	331	struct btrfs_buffer *b = list_entry(root->cache.next,
234b63a0 CM	332	struct btrfs_buffer, cache);
ed2ff2cb	333	list_del_init(&b->cache);
234b63a0	334	btrfs_block_release(root, b);
ed2ff2cb CM	335	}
	336	return 0;
	337	}
234b63a0	338	int close_ctree(struct btrfs_root root, struct btrfs_super_block s)
cfaa7295	339	{
3768f368	340	int ret;
234b63a0	341	btrfs_commit_transaction(root, s);
3768f368 CM	342	ret = commit_extent_and_tree_roots(root->tree_root, root->extent_root);
3768f368 CM	343	BUG_ON(ret);
a28ec197	344	write_ctree_super(root, s);
ed2ff2cb	345	drop_cache(root->extent_root);
3768f368	346	drop_cache(root->tree_root);
ed2ff2cb CM	347	drop_cache(root);
	348	BUG_ON(!list_empty(&root->trans));
	349	BUG_ON(!list_empty(&root->extent_root->trans));
3768f368	350	BUG_ON(!list_empty(&root->tree_root->trans));
ed2ff2cb	351
cfaa7295 CM	352	close(root->fp);
cfaa7295 CM	353	if (root->node)
234b63a0	354	btrfs_block_release(root, root->node);
cfaa7295	355	if (root->extent_root->node)
234b63a0	356	btrfs_block_release(root->extent_root, root->extent_root->node);
3768f368 CM	357	if (root->tree_root->node)
3768f368 CM	358	btrfs_block_release(root->tree_root, root->tree_root->node);
234b63a0	359	btrfs_block_release(root, root->commit_root);
cfaa7295 CM	360	free(root);
cfaa7295 CM	361	printf("on close %d blocks are allocated\n", allocated_blocks);
eb60ceac CM	362	return 0;
	363	}
	364
234b63a0	365	void btrfs_block_release(struct btrfs_root root, struct btrfs_buffer buf)
eb60ceac CM	366	{
eb60ceac CM	367	buf->count--;
cfaa7295 CM	368	if (buf->count < 0)
cfaa7295 CM	369	BUG();
eb60ceac	370	if (buf->count == 0) {
02217ed2 CM	371	BUG_ON(!list_empty(&buf->cache));
02217ed2 CM	372	BUG_ON(!list_empty(&buf->dirty));
eb60ceac CM	373	if (!radix_tree_lookup(&root->cache_radix, buf->blocknr))
	374	BUG();
	375	radix_tree_delete(&root->cache_radix, buf->blocknr);
	376	memset(buf, 0, sizeof(*buf));
	377	free(buf);
	378	BUG_ON(allocated_blocks == 0);
	379	allocated_blocks--;
ed2ff2cb CM	380	BUG_ON(root->cache_size == 0);
ed2ff2cb CM	381	root->cache_size--;
eb60ceac CM	382	}
	383	}
	384