[deliverable/linux.git] / fs / hfsplus / btree.c

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

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

#include "hfsplus_fs.h"
#include "hfsplus_raw.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)
{
	struct hfs_btree *tree;
	struct hfs_btree_header_rec *head;
	struct address_space *mapping;
	struct inode *inode;
	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);
	tree->sb = sb;
	tree->cnid = id;
	inode = hfsplus_iget(sb, id);
	if (IS_ERR(inode))
		goto free_tree;
	tree->inode = inode;

	if (!HFSPLUS_I(tree->inode)->first_blocks) {
		pr_err("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);

	/* Verify the tree and set the correct compare function */
	switch (id) {
	case HFSPLUS_EXT_CNID:
		if (tree->max_key_len != HFSPLUS_EXT_KEYLEN - sizeof(u16)) {
			pr_err("invalid extent max_key_len %d\n",
				tree->max_key_len);
			goto fail_page;
		}
		if (tree->attributes & HFS_TREE_VARIDXKEYS) {
			pr_err("invalid extent btree flag\n");
			goto fail_page;
		}

		tree->keycmp = hfsplus_ext_cmp_key;
		break;
	case HFSPLUS_CAT_CNID:
		if (tree->max_key_len != HFSPLUS_CAT_KEYLEN - sizeof(u16)) {
			pr_err("invalid catalog max_key_len %d\n",
				tree->max_key_len);
			goto fail_page;
		}
		if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
			pr_err("invalid catalog btree flag\n");
			goto fail_page;
		}

		if (test_bit(HFSPLUS_SB_HFSX, &HFSPLUS_SB(sb)->flags) &&
		    (head->key_type == HFSPLUS_KEY_BINARY))
			tree->keycmp = hfsplus_cat_bin_cmp_key;
		else {
			tree->keycmp = hfsplus_cat_case_cmp_key;
			set_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags);
		}
		break;
	case HFSPLUS_ATTR_CNID:
		if (tree->max_key_len != HFSPLUS_ATTR_KEYLEN - sizeof(u16)) {
			pr_err("invalid attributes max_key_len %d\n",
				tree->max_key_len);
			goto fail_page;
		}
		tree->keycmp = hfsplus_attr_bin_cmp_key;
		break;
	default:
		pr_err("unknown B*Tree requested\n");
		goto fail_page;
	}

	if (!(tree->attributes & HFS_TREE_BIGKEYS)) {
		pr_err("invalid btree flag\n");
		goto fail_page;
	}

	size = tree->node_size;
	if (!is_power_of_2(size))
		goto fail_page;
	if (!tree->node_count)
		goto fail_page;

	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 = &hfsplus_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))
				pr_crit("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);
}

int 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 -EIO;
	/* 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);
	return 0;
}

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;

	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;
		struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
		u32 count;
		int res;

		res = hfsplus_file_extend(inode);
		if (res)
			return ERR_PTR(res);
		hip->phys_size = inode->i_size =
			(loff_t)hip->alloc_blocks <<
				HFSPLUS_SB(tree->sb)->alloc_blksz_shift;
		hip->fs_blocks =
			hip->alloc_blocks << HFSPLUS_SB(tree->sb)->fs_shift;
		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) {
			hfs_dbg(BNODE_MOD, "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;

	hfs_dbg(BNODE_MOD, "btree_free_node: %u\n", node->this);
	BUG_ON(!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 */;
			pr_crit("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 */;
			pr_crit("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)) {
		pr_crit("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/hfsplus/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/slab.h>
	12	#include <linux/pagemap.h>
e1b5c1d3	13	#include <linux/log2.h>
1da177e4 LT	14
	15	#include "hfsplus_fs.h"
	16	#include "hfsplus_raw.h"
	17
	18
	19	/* Get a reference to a BTree and do some initial checks /
	20	struct hfs_btree hfs_btree_open(struct super_block sb, u32 id)
	21	{
	22	struct hfs_btree *tree;
	23	struct hfs_btree_header_rec *head;
	24	struct address_space *mapping;
63525391	25	struct inode *inode;
1da177e4 LT	26	struct page *page;
	27	unsigned int size;
	28
f8314dc6	29	tree = kzalloc(sizeof(*tree), GFP_KERNEL);
1da177e4 LT	30	if (!tree)
1da177e4 LT	31	return NULL;
1da177e4	32
467c3d9c	33	mutex_init(&tree->tree_lock);
1da177e4	34	spin_lock_init(&tree->hash_lock);
1da177e4 LT	35	tree->sb = sb;
1da177e4 LT	36	tree->cnid = id;
63525391 DH	37	inode = hfsplus_iget(sb, id);
63525391 DH	38	if (IS_ERR(inode))
1da177e4	39	goto free_tree;
63525391	40	tree->inode = inode;
1da177e4	41
ee527162	42	if (!HFSPLUS_I(tree->inode)->first_blocks) {
d6142673	43	pr_err("invalid btree extent records (0 size)\n");
ee527162 JM	44	goto free_inode;
	45	}
	46
1da177e4	47	mapping = tree->inode->i_mapping;
090d2b18	48	page = read_mapping_page(mapping, 0, NULL);
1da177e4	49	if (IS_ERR(page))
ee527162	50	goto free_inode;
1da177e4 LT	51
1da177e4 LT	52	/* Load the header */
2753cc28 AS	53	head = (struct hfs_btree_header_rec *)(kmap(page) +
2753cc28 AS	54	sizeof(struct hfs_bnode_desc));
1da177e4 LT	55	tree->root = be32_to_cpu(head->root);
	56	tree->leaf_count = be32_to_cpu(head->leaf_count);
	57	tree->leaf_head = be32_to_cpu(head->leaf_head);
	58	tree->leaf_tail = be32_to_cpu(head->leaf_tail);
	59	tree->node_count = be32_to_cpu(head->node_count);
	60	tree->free_nodes = be32_to_cpu(head->free_nodes);
	61	tree->attributes = be32_to_cpu(head->attributes);
	62	tree->node_size = be16_to_cpu(head->node_size);
	63	tree->max_key_len = be16_to_cpu(head->max_key_len);
	64	tree->depth = be16_to_cpu(head->depth);
	65
9250f925 ES	66	/* Verify the tree and set the correct compare function */
	67	switch (id) {
	68	case HFSPLUS_EXT_CNID:
	69	if (tree->max_key_len != HFSPLUS_EXT_KEYLEN - sizeof(u16)) {
d6142673	70	pr_err("invalid extent max_key_len %d\n",
9250f925 ES	71	tree->max_key_len);
	72	goto fail_page;
	73	}
13571a69	74	if (tree->attributes & HFS_TREE_VARIDXKEYS) {
d6142673	75	pr_err("invalid extent btree flag\n");
13571a69 CH	76	goto fail_page;
	77	}
	78
2179d372	79	tree->keycmp = hfsplus_ext_cmp_key;
9250f925 ES	80	break;
	81	case HFSPLUS_CAT_CNID:
	82	if (tree->max_key_len != HFSPLUS_CAT_KEYLEN - sizeof(u16)) {
d6142673	83	pr_err("invalid catalog max_key_len %d\n",
9250f925 ES	84	tree->max_key_len);
	85	goto fail_page;
	86	}
13571a69	87	if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
d6142673	88	pr_err("invalid catalog btree flag\n");
13571a69 CH	89	goto fail_page;
13571a69 CH	90	}
9250f925	91
84adede3	92	if (test_bit(HFSPLUS_SB_HFSX, &HFSPLUS_SB(sb)->flags) &&
2179d372 DE	93	(head->key_type == HFSPLUS_KEY_BINARY))
2179d372 DE	94	tree->keycmp = hfsplus_cat_bin_cmp_key;
d45bce8f	95	else {
2179d372	96	tree->keycmp = hfsplus_cat_case_cmp_key;
84adede3	97	set_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags);
d45bce8f	98	}
9250f925	99	break;
324ef39a VD	100	case HFSPLUS_ATTR_CNID:
324ef39a VD	101	if (tree->max_key_len != HFSPLUS_ATTR_KEYLEN - sizeof(u16)) {
d6142673	102	pr_err("invalid attributes max_key_len %d\n",
324ef39a VD	103	tree->max_key_len);
	104	goto fail_page;
	105	}
	106	tree->keycmp = hfsplus_attr_bin_cmp_key;
	107	break;
9250f925	108	default:
d6142673	109	pr_err("unknown B*Tree requested\n");
2179d372 DE	110	goto fail_page;
	111	}
	112
13571a69	113	if (!(tree->attributes & HFS_TREE_BIGKEYS)) {
d6142673	114	pr_err("invalid btree flag\n");
13571a69 CH	115	goto fail_page;
	116	}
	117
1da177e4	118	size = tree->node_size;
e1b5c1d3	119	if (!is_power_of_2(size))
1da177e4 LT	120	goto fail_page;
	121	if (!tree->node_count)
	122	goto fail_page;
9250f925	123
1da177e4 LT	124	tree->node_size_shift = ffs(size) - 1;
1da177e4 LT	125
2753cc28 AS	126	tree->pages_per_bnode =
	127	(tree->node_size + PAGE_CACHE_SIZE - 1) >>
	128	PAGE_CACHE_SHIFT;
1da177e4 LT	129
	130	kunmap(page);
	131	page_cache_release(page);
	132	return tree;
	133
	134	fail_page:
1da177e4	135	page_cache_release(page);
ee527162	136	free_inode:
9250f925	137	tree->inode->i_mapping->a_ops = &hfsplus_aops;
1da177e4	138	iput(tree->inode);
ee527162	139	free_tree:
1da177e4 LT	140	kfree(tree);
	141	return NULL;
	142	}
	143
	144	/* Release resources used by a btree */
	145	void hfs_btree_close(struct hfs_btree *tree)
	146	{
	147	struct hfs_bnode *node;
	148	int i;
	149
	150	if (!tree)
	151	return;
	152
	153	for (i = 0; i < NODE_HASH_SIZE; i++) {
	154	while ((node = tree->node_hash[i])) {
	155	tree->node_hash[i] = node->next_hash;
	156	if (atomic_read(&node->refcnt))
d6142673	157	pr_crit("node %d:%d "
2753cc28 AS	158	"still has %d user(s)!\n",
	159	node->tree->cnid, node->this,
	160	atomic_read(&node->refcnt));
1da177e4 LT	161	hfs_bnode_free(node);
	162	tree->node_hash_cnt--;
	163	}
	164	}
	165	iput(tree->inode);
	166	kfree(tree);
	167	}
	168
81cc7fad	169	int hfs_btree_write(struct hfs_btree *tree)
1da177e4 LT	170	{
	171	struct hfs_btree_header_rec *head;
	172	struct hfs_bnode *node;
	173	struct page *page;
	174
	175	node = hfs_bnode_find(tree, 0);
	176	if (IS_ERR(node))
	177	/* panic? */
81cc7fad	178	return -EIO;
1da177e4 LT	179	/* Load the header */
1da177e4 LT	180	page = node->page[0];
2753cc28 AS	181	head = (struct hfs_btree_header_rec *)(kmap(page) +
2753cc28 AS	182	sizeof(struct hfs_bnode_desc));
1da177e4 LT	183
	184	head->root = cpu_to_be32(tree->root);
	185	head->leaf_count = cpu_to_be32(tree->leaf_count);
	186	head->leaf_head = cpu_to_be32(tree->leaf_head);
	187	head->leaf_tail = cpu_to_be32(tree->leaf_tail);
	188	head->node_count = cpu_to_be32(tree->node_count);
	189	head->free_nodes = cpu_to_be32(tree->free_nodes);
	190	head->attributes = cpu_to_be32(tree->attributes);
	191	head->depth = cpu_to_be16(tree->depth);
	192
	193	kunmap(page);
	194	set_page_dirty(page);
	195	hfs_bnode_put(node);
81cc7fad	196	return 0;
1da177e4 LT	197	}
	198
	199	static struct hfs_bnode hfs_bmap_new_bmap(struct hfs_bnode prev, u32 idx)
	200	{
	201	struct hfs_btree *tree = prev->tree;
	202	struct hfs_bnode *node;
	203	struct hfs_bnode_desc desc;
	204	__be32 cnid;
	205
	206	node = hfs_bnode_create(tree, idx);
	207	if (IS_ERR(node))
	208	return node;
	209
	210	tree->free_nodes--;
	211	prev->next = idx;
	212	cnid = cpu_to_be32(idx);
	213	hfs_bnode_write(prev, &cnid, offsetof(struct hfs_bnode_desc, next), 4);
	214
	215	node->type = HFS_NODE_MAP;
	216	node->num_recs = 1;
	217	hfs_bnode_clear(node, 0, tree->node_size);
	218	desc.next = 0;
	219	desc.prev = 0;
	220	desc.type = HFS_NODE_MAP;
	221	desc.height = 0;
	222	desc.num_recs = cpu_to_be16(1);
	223	desc.reserved = 0;
	224	hfs_bnode_write(node, &desc, 0, sizeof(desc));
	225	hfs_bnode_write_u16(node, 14, 0x8000);
	226	hfs_bnode_write_u16(node, tree->node_size - 2, 14);
	227	hfs_bnode_write_u16(node, tree->node_size - 4, tree->node_size - 6);
	228
	229	return node;
	230	}
	231
	232	struct hfs_bnode hfs_bmap_alloc(struct hfs_btree tree)
	233	{
	234	struct hfs_bnode node, next_node;
	235	struct page **pagep;
	236	u32 nidx, idx;
487798df AM	237	unsigned off;
	238	u16 off16;
	239	u16 len;
1da177e4 LT	240	u8 *data, byte, m;
	241	int i;
	242
	243	while (!tree->free_nodes) {
	244	struct inode *inode = tree->inode;
6af502de	245	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
1da177e4 LT	246	u32 count;
	247	int res;
	248
	249	res = hfsplus_file_extend(inode);
	250	if (res)
	251	return ERR_PTR(res);
6af502de CH	252	hip->phys_size = inode->i_size =
6af502de CH	253	(loff_t)hip->alloc_blocks <<
dd73a01a	254	HFSPLUS_SB(tree->sb)->alloc_blksz_shift;
6af502de CH	255	hip->fs_blocks =
6af502de CH	256	hip->alloc_blocks << HFSPLUS_SB(tree->sb)->fs_shift;
1da177e4 LT	257	inode_set_bytes(inode, inode->i_size);
	258	count = inode->i_size >> tree->node_size_shift;
	259	tree->free_nodes = count - tree->node_count;
	260	tree->node_count = count;
	261	}
	262
	263	nidx = 0;
	264	node = hfs_bnode_find(tree, nidx);
	265	if (IS_ERR(node))
	266	return node;
487798df AM	267	len = hfs_brec_lenoff(node, 2, &off16);
487798df AM	268	off = off16;
1da177e4 LT	269
	270	off += node->page_offset;
	271	pagep = node->page + (off >> PAGE_CACHE_SHIFT);
	272	data = kmap(*pagep);
	273	off &= ~PAGE_CACHE_MASK;
	274	idx = 0;
	275
	276	for (;;) {
	277	while (len) {
	278	byte = data[off];
	279	if (byte != 0xff) {
	280	for (m = 0x80, i = 0; i < 8; m >>= 1, i++) {
	281	if (!(byte & m)) {
	282	idx += i;
	283	data[off] \|= m;
	284	set_page_dirty(*pagep);
	285	kunmap(*pagep);
	286	tree->free_nodes--;
	287	mark_inode_dirty(tree->inode);
	288	hfs_bnode_put(node);
2753cc28 AS	289	return hfs_bnode_create(tree,
2753cc28 AS	290	idx);
1da177e4 LT	291	}
	292	}
	293	}
	294	if (++off >= PAGE_CACHE_SIZE) {
	295	kunmap(*pagep);
	296	data = kmap(*++pagep);
	297	off = 0;
	298	}
	299	idx += 8;
	300	len--;
	301	}
	302	kunmap(*pagep);
	303	nidx = node->next;
	304	if (!nidx) {
c2b3e1f7	305	hfs_dbg(BNODE_MOD, "create new bmap node\n");
1da177e4 LT	306	next_node = hfs_bmap_new_bmap(node, idx);
	307	} else
	308	next_node = hfs_bnode_find(tree, nidx);
	309	hfs_bnode_put(node);
	310	if (IS_ERR(next_node))
	311	return next_node;
	312	node = next_node;
	313
487798df AM	314	len = hfs_brec_lenoff(node, 0, &off16);
487798df AM	315	off = off16;
1da177e4 LT	316	off += node->page_offset;
	317	pagep = node->page + (off >> PAGE_CACHE_SHIFT);
	318	data = kmap(*pagep);
	319	off &= ~PAGE_CACHE_MASK;
	320	}
	321	}
	322
	323	void hfs_bmap_free(struct hfs_bnode *node)
	324	{
	325	struct hfs_btree *tree;
	326	struct page *page;
	327	u16 off, len;
	328	u32 nidx;
	329	u8 *data, byte, m;
	330
c2b3e1f7	331	hfs_dbg(BNODE_MOD, "btree_free_node: %u\n", node->this);
0bf3ba53	332	BUG_ON(!node->this);
1da177e4 LT	333	tree = node->tree;
	334	nidx = node->this;
	335	node = hfs_bnode_find(tree, 0);
	336	if (IS_ERR(node))
	337	return;
	338	len = hfs_brec_lenoff(node, 2, &off);
	339	while (nidx >= len * 8) {
	340	u32 i;
	341
	342	nidx -= len * 8;
	343	i = node->next;
	344	hfs_bnode_put(node);
	345	if (!i) {
	346	/* panic */;
d6142673	347	pr_crit("unable to free bnode %u. "
2753cc28 AS	348	"bmap not found!\n",
2753cc28 AS	349	node->this);
1da177e4 LT	350	return;
	351	}
	352	node = hfs_bnode_find(tree, i);
	353	if (IS_ERR(node))
	354	return;
	355	if (node->type != HFS_NODE_MAP) {
	356	/* panic */;
d6142673	357	pr_crit("invalid bmap found! "
2753cc28 AS	358	"(%u,%d)\n",
2753cc28 AS	359	node->this, node->type);
1da177e4 LT	360	hfs_bnode_put(node);
	361	return;
	362	}
	363	len = hfs_brec_lenoff(node, 0, &off);
	364	}
	365	off += node->page_offset + nidx / 8;
	366	page = node->page[off >> PAGE_CACHE_SHIFT];
	367	data = kmap(page);
	368	off &= ~PAGE_CACHE_MASK;
	369	m = 1 << (~nidx & 7);
	370	byte = data[off];
	371	if (!(byte & m)) {
d6142673	372	pr_crit("trying to free free bnode "
2753cc28 AS	373	"%u(%d)\n",
2753cc28 AS	374	node->this, node->type);
1da177e4 LT	375	kunmap(page);
	376	hfs_bnode_put(node);
	377	return;
	378	}
	379	data[off] = byte & ~m;
	380	set_page_dirty(page);
	381	kunmap(page);
	382	hfs_bnode_put(node);
	383	tree->free_nodes++;
	384	mark_inode_dirty(tree->inode);
	385	}