[net-next-2.6.git] / fs / hfs / btree.c

/*
 *  linux/fs/hfs/btree.c
 *
 * Copyright (C) 2001
 * Brad Boyer (flar@allandria.com)
 * (C) 2003 Ardis Technologies <roman@ardistech.com>
 *
 * Handle opening/closing btree
 */

#include <linux/pagemap.h>
#include <linux/slab.h>
#include <linux/log2.h>

#include "btree.h"

/* Get a reference to a B*Tree and do some initial checks */
struct hfs_btree *hfs_btree_open(struct super_block *sb, u32 id, btree_keycmp keycmp)
{
	struct hfs_btree *tree;
	struct hfs_btree_header_rec *head;
	struct address_space *mapping;
	struct page *page;
	unsigned int size;

	tree = kzalloc(sizeof(*tree), GFP_KERNEL);
	if (!tree)
		return NULL;

	mutex_init(&tree->tree_lock);
	spin_lock_init(&tree->hash_lock);
	/* Set the correct compare function */
	tree->sb = sb;
	tree->cnid = id;
	tree->keycmp = keycmp;

	tree->inode = iget_locked(sb, id);
	if (!tree->inode)
		goto free_tree;
	BUG_ON(!(tree->inode->i_state & I_NEW));
	{
	struct hfs_mdb *mdb = HFS_SB(sb)->mdb;
	HFS_I(tree->inode)->flags = 0;
	mutex_init(&HFS_I(tree->inode)->extents_lock);
	switch (id) {
	case HFS_EXT_CNID:
		hfs_inode_read_fork(tree->inode, mdb->drXTExtRec, mdb->drXTFlSize,
				    mdb->drXTFlSize, be32_to_cpu(mdb->drXTClpSiz));
		tree->inode->i_mapping->a_ops = &hfs_btree_aops;
		break;
	case HFS_CAT_CNID:
		hfs_inode_read_fork(tree->inode, mdb->drCTExtRec, mdb->drCTFlSize,
				    mdb->drCTFlSize, be32_to_cpu(mdb->drCTClpSiz));
		tree->inode->i_mapping->a_ops = &hfs_btree_aops;
		break;
	default:
		BUG();
	}
	}
	unlock_new_inode(tree->inode);

	if (!HFS_I(tree->inode)->first_blocks) {
		printk(KERN_ERR "hfs: invalid btree extent records (0 size).\n");
		goto free_inode;
	}

	mapping = tree->inode->i_mapping;
	page = read_mapping_page(mapping, 0, NULL);
	if (IS_ERR(page))
		goto free_inode;

	/* Load the header */
	head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc));
	tree->root = be32_to_cpu(head->root);
	tree->leaf_count = be32_to_cpu(head->leaf_count);
	tree->leaf_head = be32_to_cpu(head->leaf_head);
	tree->leaf_tail = be32_to_cpu(head->leaf_tail);
	tree->node_count = be32_to_cpu(head->node_count);
	tree->free_nodes = be32_to_cpu(head->free_nodes);
	tree->attributes = be32_to_cpu(head->attributes);
	tree->node_size = be16_to_cpu(head->node_size);
	tree->max_key_len = be16_to_cpu(head->max_key_len);
	tree->depth = be16_to_cpu(head->depth);

	size = tree->node_size;
	if (!is_power_of_2(size))
		goto fail_page;
	if (!tree->node_count)
		goto fail_page;
	switch (id) {
	case HFS_EXT_CNID:
		if (tree->max_key_len != HFS_MAX_EXT_KEYLEN) {
			printk(KERN_ERR "hfs: invalid extent max_key_len %d\n",
				tree->max_key_len);
			goto fail_page;
		}
		break;
	case HFS_CAT_CNID:
		if (tree->max_key_len != HFS_MAX_CAT_KEYLEN) {
			printk(KERN_ERR "hfs: invalid catalog max_key_len %d\n",
				tree->max_key_len);
			goto fail_page;
		}
		break;
	default:
		BUG();
	}

	tree->node_size_shift = ffs(size) - 1;
	tree->pages_per_bnode = (tree->node_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;

	kunmap(page);
	page_cache_release(page);
	return tree;

fail_page:
	page_cache_release(page);
free_inode:
	tree->inode->i_mapping->a_ops = &hfs_aops;
	iput(tree->inode);
free_tree:
	kfree(tree);
	return NULL;
}

/* Release resources used by a btree */
void hfs_btree_close(struct hfs_btree *tree)
{
	struct hfs_bnode *node;
	int i;

	if (!tree)
		return;

	for (i = 0; i < NODE_HASH_SIZE; i++) {
		while ((node = tree->node_hash[i])) {
			tree->node_hash[i] = node->next_hash;
			if (atomic_read(&node->refcnt))
				printk(KERN_ERR "hfs: node %d:%d still has %d user(s)!\n",
					node->tree->cnid, node->this, atomic_read(&node->refcnt));
			hfs_bnode_free(node);
			tree->node_hash_cnt--;
		}
	}
	iput(tree->inode);
	kfree(tree);
}

void hfs_btree_write(struct hfs_btree *tree)
{
	struct hfs_btree_header_rec *head;
	struct hfs_bnode *node;
	struct page *page;

	node = hfs_bnode_find(tree, 0);
	if (IS_ERR(node))
		/* panic? */
		return;
	/* Load the header */
	page = node->page[0];
	head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc));

	head->root = cpu_to_be32(tree->root);
	head->leaf_count = cpu_to_be32(tree->leaf_count);
	head->leaf_head = cpu_to_be32(tree->leaf_head);
	head->leaf_tail = cpu_to_be32(tree->leaf_tail);
	head->node_count = cpu_to_be32(tree->node_count);
	head->free_nodes = cpu_to_be32(tree->free_nodes);
	head->attributes = cpu_to_be32(tree->attributes);
	head->depth = cpu_to_be16(tree->depth);

	kunmap(page);
	set_page_dirty(page);
	hfs_bnode_put(node);
}

static struct hfs_bnode *hfs_bmap_new_bmap(struct hfs_bnode *prev, u32 idx)
{
	struct hfs_btree *tree = prev->tree;
	struct hfs_bnode *node;
	struct hfs_bnode_desc desc;
	__be32 cnid;

	node = hfs_bnode_create(tree, idx);
	if (IS_ERR(node))
		return node;

	if (!tree->free_nodes)
		panic("FIXME!!!");
	tree->free_nodes--;
	prev->next = idx;
	cnid = cpu_to_be32(idx);
	hfs_bnode_write(prev, &cnid, offsetof(struct hfs_bnode_desc, next), 4);

	node->type = HFS_NODE_MAP;
	node->num_recs = 1;
	hfs_bnode_clear(node, 0, tree->node_size);
	desc.next = 0;
	desc.prev = 0;
	desc.type = HFS_NODE_MAP;
	desc.height = 0;
	desc.num_recs = cpu_to_be16(1);
	desc.reserved = 0;
	hfs_bnode_write(node, &desc, 0, sizeof(desc));
	hfs_bnode_write_u16(node, 14, 0x8000);
	hfs_bnode_write_u16(node, tree->node_size - 2, 14);
	hfs_bnode_write_u16(node, tree->node_size - 4, tree->node_size - 6);

	return node;
}

struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *tree)
{
	struct hfs_bnode *node, *next_node;
	struct page **pagep;
	u32 nidx, idx;
	unsigned off;
	u16 off16;
	u16 len;
	u8 *data, byte, m;
	int i;

	while (!tree->free_nodes) {
		struct inode *inode = tree->inode;
		u32 count;
		int res;

		res = hfs_extend_file(inode);
		if (res)
			return ERR_PTR(res);
		HFS_I(inode)->phys_size = inode->i_size =
				(loff_t)HFS_I(inode)->alloc_blocks *
				HFS_SB(tree->sb)->alloc_blksz;
		HFS_I(inode)->fs_blocks = inode->i_size >>
					  tree->sb->s_blocksize_bits;
		inode_set_bytes(inode, inode->i_size);
		count = inode->i_size >> tree->node_size_shift;
		tree->free_nodes = count - tree->node_count;
		tree->node_count = count;
	}

	nidx = 0;
	node = hfs_bnode_find(tree, nidx);
	if (IS_ERR(node))
		return node;
	len = hfs_brec_lenoff(node, 2, &off16);
	off = off16;

	off += node->page_offset;
	pagep = node->page + (off >> PAGE_CACHE_SHIFT);
	data = kmap(*pagep);
	off &= ~PAGE_CACHE_MASK;
	idx = 0;

	for (;;) {
		while (len) {
			byte = data[off];
			if (byte != 0xff) {
				for (m = 0x80, i = 0; i < 8; m >>= 1, i++) {
					if (!(byte & m)) {
						idx += i;
						data[off] |= m;
						set_page_dirty(*pagep);
						kunmap(*pagep);
						tree->free_nodes--;
						mark_inode_dirty(tree->inode);
						hfs_bnode_put(node);
						return hfs_bnode_create(tree, idx);
					}
				}
			}
			if (++off >= PAGE_CACHE_SIZE) {
				kunmap(*pagep);
				data = kmap(*++pagep);
				off = 0;
			}
			idx += 8;
			len--;
		}
		kunmap(*pagep);
		nidx = node->next;
		if (!nidx) {
			printk(KERN_DEBUG "hfs: create new bmap node...\n");
			next_node = hfs_bmap_new_bmap(node, idx);
		} else
			next_node = hfs_bnode_find(tree, nidx);
		hfs_bnode_put(node);
		if (IS_ERR(next_node))
			return next_node;
		node = next_node;

		len = hfs_brec_lenoff(node, 0, &off16);
		off = off16;
		off += node->page_offset;
		pagep = node->page + (off >> PAGE_CACHE_SHIFT);
		data = kmap(*pagep);
		off &= ~PAGE_CACHE_MASK;
	}
}

void hfs_bmap_free(struct hfs_bnode *node)
{
	struct hfs_btree *tree;
	struct page *page;
	u16 off, len;
	u32 nidx;
	u8 *data, byte, m;

	dprint(DBG_BNODE_MOD, "btree_free_node: %u\n", node->this);
	tree = node->tree;
	nidx = node->this;
	node = hfs_bnode_find(tree, 0);
	if (IS_ERR(node))
		return;
	len = hfs_brec_lenoff(node, 2, &off);
	while (nidx >= len * 8) {
		u32 i;

		nidx -= len * 8;
		i = node->next;
		hfs_bnode_put(node);
		if (!i) {
			/* panic */;
			printk(KERN_CRIT "hfs: unable to free bnode %u. bmap not found!\n", node->this);
			return;
		}
		node = hfs_bnode_find(tree, i);
		if (IS_ERR(node))
			return;
		if (node->type != HFS_NODE_MAP) {
			/* panic */;
			printk(KERN_CRIT "hfs: invalid bmap found! (%u,%d)\n", node->this, node->type);
			hfs_bnode_put(node);
			return;
		}
		len = hfs_brec_lenoff(node, 0, &off);
	}
	off += node->page_offset + nidx / 8;
	page = node->page[off >> PAGE_CACHE_SHIFT];
	data = kmap(page);
	off &= ~PAGE_CACHE_MASK;
	m = 1 << (~nidx & 7);
	byte = data[off];
	if (!(byte & m)) {
		printk(KERN_CRIT "hfs: trying to free free bnode %u(%d)\n", node->this, node->type);
		kunmap(page);
		hfs_bnode_put(node);
		return;
	}
	data[off] = byte & ~m;
	set_page_dirty(page);
	kunmap(page);
	hfs_bnode_put(node);
	tree->free_nodes++;
	mark_inode_dirty(tree->inode);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/hfs/btree.c
	3	*
	4	* Copyright (C) 2001
	5	* Brad Boyer (flar@allandria.com)
	6	* (C) 2003 Ardis Technologies <roman@ardistech.com>
	7	*
	8	* Handle opening/closing btree
	9	*/
	10
	11	#include <linux/pagemap.h>
5a0e3ad6	12	#include <linux/slab.h>
e1b5c1d3	13	#include <linux/log2.h>
1da177e4 LT	14
	15	#include "btree.h"
	16
	17	/* Get a reference to a BTree and do some initial checks /
	18	struct hfs_btree hfs_btree_open(struct super_block sb, u32 id, btree_keycmp keycmp)
	19	{
	20	struct hfs_btree *tree;
	21	struct hfs_btree_header_rec *head;
	22	struct address_space *mapping;
	23	struct page *page;
	24	unsigned int size;
	25
f8314dc6	26	tree = kzalloc(sizeof(*tree), GFP_KERNEL);
1da177e4 LT	27	if (!tree)
1da177e4 LT	28	return NULL;
1da177e4	29
4a941035	30	mutex_init(&tree->tree_lock);
1da177e4 LT	31	spin_lock_init(&tree->hash_lock);
	32	/* Set the correct compare function */
	33	tree->sb = sb;
	34	tree->cnid = id;
	35	tree->keycmp = keycmp;
	36
	37	tree->inode = iget_locked(sb, id);
	38	if (!tree->inode)
	39	goto free_tree;
4d4ef9ab	40	BUG_ON(!(tree->inode->i_state & I_NEW));
1da177e4 LT	41	{
	42	struct hfs_mdb *mdb = HFS_SB(sb)->mdb;
	43	HFS_I(tree->inode)->flags = 0;
39f8d472	44	mutex_init(&HFS_I(tree->inode)->extents_lock);
1da177e4 LT	45	switch (id) {
	46	case HFS_EXT_CNID:
	47	hfs_inode_read_fork(tree->inode, mdb->drXTExtRec, mdb->drXTFlSize,
	48	mdb->drXTFlSize, be32_to_cpu(mdb->drXTClpSiz));
	49	tree->inode->i_mapping->a_ops = &hfs_btree_aops;
	50	break;
	51	case HFS_CAT_CNID:
	52	hfs_inode_read_fork(tree->inode, mdb->drCTExtRec, mdb->drCTFlSize,
	53	mdb->drCTFlSize, be32_to_cpu(mdb->drCTClpSiz));
	54	tree->inode->i_mapping->a_ops = &hfs_btree_aops;
	55	break;
	56	default:
	57	BUG();
	58	}
	59	}
	60	unlock_new_inode(tree->inode);
	61
47f365eb JM	62	if (!HFS_I(tree->inode)->first_blocks) {
	63	printk(KERN_ERR "hfs: invalid btree extent records (0 size).\n");
	64	goto free_inode;
	65	}
	66
1da177e4	67	mapping = tree->inode->i_mapping;
090d2b18	68	page = read_mapping_page(mapping, 0, NULL);
1da177e4	69	if (IS_ERR(page))
46a39c1c	70	goto free_inode;
1da177e4 LT	71
	72	/* Load the header */
	73	head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc));
	74	tree->root = be32_to_cpu(head->root);
	75	tree->leaf_count = be32_to_cpu(head->leaf_count);
	76	tree->leaf_head = be32_to_cpu(head->leaf_head);
	77	tree->leaf_tail = be32_to_cpu(head->leaf_tail);
	78	tree->node_count = be32_to_cpu(head->node_count);
	79	tree->free_nodes = be32_to_cpu(head->free_nodes);
	80	tree->attributes = be32_to_cpu(head->attributes);
	81	tree->node_size = be16_to_cpu(head->node_size);
	82	tree->max_key_len = be16_to_cpu(head->max_key_len);
	83	tree->depth = be16_to_cpu(head->depth);
	84
	85	size = tree->node_size;
e1b5c1d3	86	if (!is_power_of_2(size))
1da177e4 LT	87	goto fail_page;
	88	if (!tree->node_count)
	89	goto fail_page;
55581d01 ES	90	switch (id) {
	91	case HFS_EXT_CNID:
	92	if (tree->max_key_len != HFS_MAX_EXT_KEYLEN) {
	93	printk(KERN_ERR "hfs: invalid extent max_key_len %d\n",
	94	tree->max_key_len);
	95	goto fail_page;
	96	}
	97	break;
	98	case HFS_CAT_CNID:
	99	if (tree->max_key_len != HFS_MAX_CAT_KEYLEN) {
	100	printk(KERN_ERR "hfs: invalid catalog max_key_len %d\n",
	101	tree->max_key_len);
	102	goto fail_page;
	103	}
	104	break;
	105	default:
	106	BUG();
cf059462 ES	107	}
cf059462 ES	108
1da177e4 LT	109	tree->node_size_shift = ffs(size) - 1;
	110	tree->pages_per_bnode = (tree->node_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
	111
	112	kunmap(page);
	113	page_cache_release(page);
	114	return tree;
	115
46a39c1c	116	fail_page:
1da177e4	117	page_cache_release(page);
46a39c1c	118	free_inode:
cf059462	119	tree->inode->i_mapping->a_ops = &hfs_aops;
1da177e4	120	iput(tree->inode);
46a39c1c	121	free_tree:
1da177e4 LT	122	kfree(tree);
	123	return NULL;
	124	}
	125
	126	/* Release resources used by a btree */
	127	void hfs_btree_close(struct hfs_btree *tree)
	128	{
	129	struct hfs_bnode *node;
	130	int i;
	131
	132	if (!tree)
	133	return;
	134
	135	for (i = 0; i < NODE_HASH_SIZE; i++) {
	136	while ((node = tree->node_hash[i])) {
	137	tree->node_hash[i] = node->next_hash;
	138	if (atomic_read(&node->refcnt))
7cf3cc30	139	printk(KERN_ERR "hfs: node %d:%d still has %d user(s)!\n",
1da177e4 LT	140	node->tree->cnid, node->this, atomic_read(&node->refcnt));
	141	hfs_bnode_free(node);
	142	tree->node_hash_cnt--;
	143	}
	144	}
	145	iput(tree->inode);
	146	kfree(tree);
	147	}
	148
	149	void hfs_btree_write(struct hfs_btree *tree)
	150	{
	151	struct hfs_btree_header_rec *head;
	152	struct hfs_bnode *node;
	153	struct page *page;
	154
	155	node = hfs_bnode_find(tree, 0);
	156	if (IS_ERR(node))
	157	/* panic? */
	158	return;
	159	/* Load the header */
	160	page = node->page[0];
	161	head = (struct hfs_btree_header_rec *)(kmap(page) + sizeof(struct hfs_bnode_desc));
	162
	163	head->root = cpu_to_be32(tree->root);
	164	head->leaf_count = cpu_to_be32(tree->leaf_count);
	165	head->leaf_head = cpu_to_be32(tree->leaf_head);
	166	head->leaf_tail = cpu_to_be32(tree->leaf_tail);
	167	head->node_count = cpu_to_be32(tree->node_count);
	168	head->free_nodes = cpu_to_be32(tree->free_nodes);
	169	head->attributes = cpu_to_be32(tree->attributes);
	170	head->depth = cpu_to_be16(tree->depth);
	171
	172	kunmap(page);
	173	set_page_dirty(page);
	174	hfs_bnode_put(node);
	175	}
	176
	177	static struct hfs_bnode hfs_bmap_new_bmap(struct hfs_bnode prev, u32 idx)
	178	{
	179	struct hfs_btree *tree = prev->tree;
	180	struct hfs_bnode *node;
	181	struct hfs_bnode_desc desc;
	182	__be32 cnid;
	183
	184	node = hfs_bnode_create(tree, idx);
	185	if (IS_ERR(node))
	186	return node;
	187
	188	if (!tree->free_nodes)
	189	panic("FIXME!!!");
	190	tree->free_nodes--;
	191	prev->next = idx;
	192	cnid = cpu_to_be32(idx);
	193	hfs_bnode_write(prev, &cnid, offsetof(struct hfs_bnode_desc, next), 4);
	194
	195	node->type = HFS_NODE_MAP;
	196	node->num_recs = 1;
	197	hfs_bnode_clear(node, 0, tree->node_size);
	198	desc.next = 0;
	199	desc.prev = 0;
	200	desc.type = HFS_NODE_MAP;
	201	desc.height = 0;
	202	desc.num_recs = cpu_to_be16(1);
	203	desc.reserved = 0;
204	hfs_bnode_write(node, &desc, 0, sizeof(desc));
205	hfs_bnode_write_u16(node, 14, 0x8000);
206	hfs_bnode_write_u16(node, tree->node_size - 2, 14);
207	hfs_bnode_write_u16(node, tree->node_size - 4, tree->node_size - 6);
208
209	return node;
210	}
211
212	struct hfs_bnode hfs_bmap_alloc(struct hfs_btree tree)
213	{
214	struct hfs_bnode node, next_node;
215	struct page **pagep;
216	u32 nidx, idx;
3e5a5097 AM	217	unsigned off;
	218	u16 off16;
	219	u16 len;
1da177e4 LT	220	u8 *data, byte, m;
	221	int i;
	222
	223	while (!tree->free_nodes) {
	224	struct inode *inode = tree->inode;
	225	u32 count;
	226	int res;
	227
	228	res = hfs_extend_file(inode);
	229	if (res)
	230	return ERR_PTR(res);
	231	HFS_I(inode)->phys_size = inode->i_size =
	232	(loff_t)HFS_I(inode)->alloc_blocks *
	233	HFS_SB(tree->sb)->alloc_blksz;
	234	HFS_I(inode)->fs_blocks = inode->i_size >>
	235	tree->sb->s_blocksize_bits;
	236	inode_set_bytes(inode, inode->i_size);
	237	count = inode->i_size >> tree->node_size_shift;
	238	tree->free_nodes = count - tree->node_count;
	239	tree->node_count = count;
	240	}
	241
	242	nidx = 0;
	243	node = hfs_bnode_find(tree, nidx);
	244	if (IS_ERR(node))
	245	return node;
3e5a5097 AM	246	len = hfs_brec_lenoff(node, 2, &off16);
3e5a5097 AM	247	off = off16;
1da177e4 LT	248
	249	off += node->page_offset;
	250	pagep = node->page + (off >> PAGE_CACHE_SHIFT);
	251	data = kmap(*pagep);
	252	off &= ~PAGE_CACHE_MASK;
	253	idx = 0;
	254
	255	for (;;) {
	256	while (len) {
	257	byte = data[off];
	258	if (byte != 0xff) {
	259	for (m = 0x80, i = 0; i < 8; m >>= 1, i++) {
	260	if (!(byte & m)) {
	261	idx += i;
	262	data[off] \|= m;
	263	set_page_dirty(*pagep);
	264	kunmap(*pagep);
	265	tree->free_nodes--;
	266	mark_inode_dirty(tree->inode);
	267	hfs_bnode_put(node);
	268	return hfs_bnode_create(tree, idx);
	269	}
	270	}
	271	}
	272	if (++off >= PAGE_CACHE_SIZE) {
	273	kunmap(*pagep);
	274	data = kmap(*++pagep);
	275	off = 0;
	276	}
	277	idx += 8;
	278	len--;
	279	}
	280	kunmap(*pagep);
	281	nidx = node->next;
	282	if (!nidx) {
7cf3cc30	283	printk(KERN_DEBUG "hfs: create new bmap node...\n");
1da177e4 LT	284	next_node = hfs_bmap_new_bmap(node, idx);
	285	} else
	286	next_node = hfs_bnode_find(tree, nidx);
	287	hfs_bnode_put(node);
	288	if (IS_ERR(next_node))
	289	return next_node;
	290	node = next_node;
	291
3e5a5097 AM	292	len = hfs_brec_lenoff(node, 0, &off16);
3e5a5097 AM	293	off = off16;
1da177e4 LT	294	off += node->page_offset;
	295	pagep = node->page + (off >> PAGE_CACHE_SHIFT);
	296	data = kmap(*pagep);
	297	off &= ~PAGE_CACHE_MASK;
	298	}
	299	}
	300
	301	void hfs_bmap_free(struct hfs_bnode *node)
	302	{
	303	struct hfs_btree *tree;
	304	struct page *page;
	305	u16 off, len;
	306	u32 nidx;
	307	u8 *data, byte, m;
	308
	309	dprint(DBG_BNODE_MOD, "btree_free_node: %u\n", node->this);
	310	tree = node->tree;
	311	nidx = node->this;
	312	node = hfs_bnode_find(tree, 0);
	313	if (IS_ERR(node))
	314	return;
	315	len = hfs_brec_lenoff(node, 2, &off);
	316	while (nidx >= len * 8) {
	317	u32 i;
	318
	319	nidx -= len * 8;
	320	i = node->next;
	321	hfs_bnode_put(node);
	322	if (!i) {
	323	/* panic */;
7cf3cc30	324	printk(KERN_CRIT "hfs: unable to free bnode %u. bmap not found!\n", node->this);
1da177e4 LT	325	return;
	326	}
	327	node = hfs_bnode_find(tree, i);
	328	if (IS_ERR(node))
	329	return;
	330	if (node->type != HFS_NODE_MAP) {
	331	/* panic */;
7cf3cc30	332	printk(KERN_CRIT "hfs: invalid bmap found! (%u,%d)\n", node->this, node->type);
1da177e4 LT	333	hfs_bnode_put(node);
	334	return;
	335	}
	336	len = hfs_brec_lenoff(node, 0, &off);
	337	}
	338	off += node->page_offset + nidx / 8;
	339	page = node->page[off >> PAGE_CACHE_SHIFT];
	340	data = kmap(page);
	341	off &= ~PAGE_CACHE_MASK;
	342	m = 1 << (~nidx & 7);
	343	byte = data[off];
	344	if (!(byte & m)) {
7cf3cc30	345	printk(KERN_CRIT "hfs: trying to free free bnode %u(%d)\n", node->this, node->type);
1da177e4 LT	346	kunmap(page);
	347	hfs_bnode_put(node);
	348	return;
	349	}
	350	data[off] = byte & ~m;
	351	set_page_dirty(page);
	352	kunmap(page);
	353	hfs_bnode_put(node);
	354	tree->free_nodes++;
	355	mark_inode_dirty(tree->inode);
	356	}