[linux-2.6-block.git] / fs / hfsplus / btree.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  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"

/*
 * Initial source code of clump size calculation is gotten
 * from http://opensource.apple.com/tarballs/diskdev_cmds/
 */
#define CLUMP_ENTRIES	15

static short clumptbl[CLUMP_ENTRIES * 3] = {
/*
 *	    Volume	Attributes	 Catalog	 Extents
 *	     Size	Clump (MB)	Clump (MB)	Clump (MB)
 */
	/*   1GB */	  4,		  4,		 4,
	/*   2GB */	  6,		  6,		 4,
	/*   4GB */	  8,		  8,		 4,
	/*   8GB */	 11,		 11,		 5,
	/*
	 * For volumes 16GB and larger, we want to make sure that a full OS
	 * install won't require fragmentation of the Catalog or Attributes
	 * B-trees.  We do this by making the clump sizes sufficiently large,
	 * and by leaving a gap after the B-trees for them to grow into.
	 *
	 * For SnowLeopard 10A298, a FullNetInstall with all packages selected
	 * results in:
	 * Catalog B-tree Header
	 *	nodeSize:          8192
	 *	totalNodes:       31616
	 *	freeNodes:         1978
	 * (used = 231.55 MB)
	 * Attributes B-tree Header
	 *	nodeSize:          8192
	 *	totalNodes:       63232
	 *	freeNodes:          958
	 * (used = 486.52 MB)
	 *
	 * We also want Time Machine backup volumes to have a sufficiently
	 * large clump size to reduce fragmentation.
	 *
	 * The series of numbers for Catalog and Attribute form a geometric
	 * series. For Catalog (16GB to 512GB), each term is 8**(1/5) times
	 * the previous term.  For Attributes (16GB to 512GB), each term is
	 * 4**(1/5) times the previous term.  For 1TB to 16TB, each term is
	 * 2**(1/5) times the previous term.
	 */
	/*  16GB */	 64,		 32,		 5,
	/*  32GB */	 84,		 49,		 6,
	/*  64GB */	111,		 74,		 7,
	/* 128GB */	147,		111,		 8,
	/* 256GB */	194,		169,		 9,
	/* 512GB */	256,		256,		11,
	/*   1TB */	294,		294,		14,
	/*   2TB */	338,		338,		16,
	/*   4TB */	388,		388,		20,
	/*   8TB */	446,		446,		25,
	/*  16TB */	512,		512,		32
};

u32 hfsplus_calc_btree_clump_size(u32 block_size, u32 node_size,
					u64 sectors, int file_id)
{
	u32 mod = max(node_size, block_size);
	u32 clump_size;
	int column;
	int i;

	/* Figure out which column of the above table to use for this file. */
	switch (file_id) {
	case HFSPLUS_ATTR_CNID:
		column = 0;
		break;
	case HFSPLUS_CAT_CNID:
		column = 1;
		break;
	default:
		column = 2;
		break;
	}

	/*
	 * The default clump size is 0.8% of the volume size. And
	 * it must also be a multiple of the node and block size.
	 */
	if (sectors < 0x200000) {
		clump_size = sectors << 2;	/*  0.8 %  */
		if (clump_size < (8 * node_size))
			clump_size = 8 * node_size;
	} else {
		/* turn exponent into table index... */
		for (i = 0, sectors = sectors >> 22;
		     sectors && (i < CLUMP_ENTRIES - 1);
		     ++i, sectors = sectors >> 1) {
			/* empty body */
		}

		clump_size = clumptbl[column + (i) * 3] * 1024 * 1024;
	}

	/*
	 * Round the clump size to a multiple of node and block size.
	 * NOTE: This rounds down.
	 */
	clump_size /= mod;
	clump_size *= mod;

	/*
	 * Rounding down could have rounded down to 0 if the block size was
	 * greater than the clump size.  If so, just use one block or node.
	 */
	if (clump_size == 0)
		clump_size = mod;

	return clump_size;
}

/* 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_SIZE - 1) >>
		PAGE_SHIFT;

	kunmap(page);
	put_page(page);
	return tree;

 fail_page:
	put_page(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;
}

/* Make sure @tree has enough space for the @rsvd_nodes */
int hfs_bmap_reserve(struct hfs_btree *tree, int rsvd_nodes)
{
	struct inode *inode = tree->inode;
	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
	u32 count;
	int res;

	if (rsvd_nodes <= 0)
		return 0;

	while (tree->free_nodes < rsvd_nodes) {
		res = hfsplus_file_extend(inode, hfs_bnode_need_zeroout(tree));
		if (res)
			return 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;
	}
	return 0;
}

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, res;

	res = hfs_bmap_reserve(tree, 1);
	if (res)
		return ERR_PTR(res);

	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_SHIFT);
	data = kmap(*pagep);
	off &= ~PAGE_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_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_SHIFT);
		data = kmap(*pagep);
		off &= ~PAGE_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;
		if (!i) {
			/* panic */;
			pr_crit("unable to free bnode %u. "
					"bmap not found!\n",
				node->this);
			hfs_bnode_put(node);
			return;
		}
		hfs_bnode_put(node);
		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_SHIFT];
	data = kmap(page);
	off &= ~PAGE_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
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/hfsplus/btree.c
	4	*
	5	* Copyright (C) 2001
	6	* Brad Boyer (flar@allandria.com)
	7	* (C) 2003 Ardis Technologies <roman@ardistech.com>
	8	*
	9	* Handle opening/closing btree
	10	*/
	11
	12	#include <linux/slab.h>
	13	#include <linux/pagemap.h>
e1b5c1d3	14	#include <linux/log2.h>
1da177e4 LT	15
	16	#include "hfsplus_fs.h"
	17	#include "hfsplus_raw.h"
	18
b3b5b0f0 VD	19	/*
	20	* Initial source code of clump size calculation is gotten
	21	* from http://opensource.apple.com/tarballs/diskdev_cmds/
	22	*/
	23	#define CLUMP_ENTRIES 15
	24
	25	static short clumptbl[CLUMP_ENTRIES * 3] = {
	26	/*
	27	* Volume Attributes Catalog Extents
	28	* Size Clump (MB) Clump (MB) Clump (MB)
	29	*/
	30	/* 1GB */ 4, 4, 4,
	31	/* 2GB */ 6, 6, 4,
	32	/* 4GB */ 8, 8, 4,
	33	/* 8GB */ 11, 11, 5,
	34	/*
	35	* For volumes 16GB and larger, we want to make sure that a full OS
	36	* install won't require fragmentation of the Catalog or Attributes
	37	* B-trees. We do this by making the clump sizes sufficiently large,
	38	* and by leaving a gap after the B-trees for them to grow into.
	39	*
	40	* For SnowLeopard 10A298, a FullNetInstall with all packages selected
	41	* results in:
	42	* Catalog B-tree Header
	43	* nodeSize: 8192
	44	* totalNodes: 31616
	45	* freeNodes: 1978
	46	* (used = 231.55 MB)
	47	* Attributes B-tree Header
	48	* nodeSize: 8192
	49	* totalNodes: 63232
	50	* freeNodes: 958
	51	* (used = 486.52 MB)
	52	*
	53	* We also want Time Machine backup volumes to have a sufficiently
	54	* large clump size to reduce fragmentation.
	55	*
	56	* The series of numbers for Catalog and Attribute form a geometric
	57	* series. For Catalog (16GB to 512GB), each term is 8**(1/5) times
	58	* the previous term. For Attributes (16GB to 512GB), each term is
	59	* 4**(1/5) times the previous term. For 1TB to 16TB, each term is
	60	* 2**(1/5) times the previous term.
	61	*/
	62	/* 16GB */ 64, 32, 5,
	63	/* 32GB */ 84, 49, 6,
	64	/* 64GB */ 111, 74, 7,
	65	/* 128GB */ 147, 111, 8,
	66	/* 256GB */ 194, 169, 9,
	67	/* 512GB */ 256, 256, 11,
	68	/* 1TB */ 294, 294, 14,
	69	/* 2TB */ 338, 338, 16,
	70	/* 4TB */ 388, 388, 20,
	71	/* 8TB */ 446, 446, 25,
	72	/* 16TB */ 512, 512, 32
	73	};
	74
	75	u32 hfsplus_calc_btree_clump_size(u32 block_size, u32 node_size,
	76	u64 sectors, int file_id)
	77	{
	78	u32 mod = max(node_size, block_size);
	79	u32 clump_size;
	80	int column;
	81	int i;
	82
83	/* Figure out which column of the above table to use for this file. */
84	switch (file_id) {
85	case HFSPLUS_ATTR_CNID:
86	column = 0;
87	break;
88	case HFSPLUS_CAT_CNID:
89	column = 1;
90	break;
91	default:
92	column = 2;
93	break;
94	}
95
96	/*
97	* The default clump size is 0.8% of the volume size. And
98	* it must also be a multiple of the node and block size.
99	*/
100	if (sectors < 0x200000) {
101	clump_size = sectors << 2; /* 0.8 % */
102	if (clump_size < (8 * node_size))
103	clump_size = 8 * node_size;
104	} else {
105	/* turn exponent into table index... */
106	for (i = 0, sectors = sectors >> 22;
107	sectors && (i < CLUMP_ENTRIES - 1);
108	++i, sectors = sectors >> 1) {
109	/* empty body */
110	}
111
112	clump_size = clumptbl[column + (i) * 3] * 1024 * 1024;
113	}
114
115	/*
116	* Round the clump size to a multiple of node and block size.
117	* NOTE: This rounds down.
118	*/
119	clump_size /= mod;
120	clump_size *= mod;
121
122	/*
123	* Rounding down could have rounded down to 0 if the block size was
124	* greater than the clump size. If so, just use one block or node.
125	*/
126	if (clump_size == 0)
127	clump_size = mod;
128
129	return clump_size;
130	}
1da177e4 LT	131
	132	/* Get a reference to a BTree and do some initial checks /
	133	struct hfs_btree hfs_btree_open(struct super_block sb, u32 id)
	134	{
	135	struct hfs_btree *tree;
	136	struct hfs_btree_header_rec *head;
	137	struct address_space *mapping;
63525391	138	struct inode *inode;
1da177e4 LT	139	struct page *page;
	140	unsigned int size;
	141
f8314dc6	142	tree = kzalloc(sizeof(*tree), GFP_KERNEL);
1da177e4 LT	143	if (!tree)
1da177e4 LT	144	return NULL;
1da177e4	145
467c3d9c	146	mutex_init(&tree->tree_lock);
1da177e4	147	spin_lock_init(&tree->hash_lock);
1da177e4 LT	148	tree->sb = sb;
1da177e4 LT	149	tree->cnid = id;
63525391 DH	150	inode = hfsplus_iget(sb, id);
63525391 DH	151	if (IS_ERR(inode))
1da177e4	152	goto free_tree;
63525391	153	tree->inode = inode;
1da177e4	154
ee527162	155	if (!HFSPLUS_I(tree->inode)->first_blocks) {
d6142673	156	pr_err("invalid btree extent records (0 size)\n");
ee527162 JM	157	goto free_inode;
	158	}
	159
1da177e4	160	mapping = tree->inode->i_mapping;
090d2b18	161	page = read_mapping_page(mapping, 0, NULL);
1da177e4	162	if (IS_ERR(page))
ee527162	163	goto free_inode;
1da177e4 LT	164
1da177e4 LT	165	/* Load the header */
2753cc28 AS	166	head = (struct hfs_btree_header_rec *)(kmap(page) +
2753cc28 AS	167	sizeof(struct hfs_bnode_desc));
1da177e4 LT	168	tree->root = be32_to_cpu(head->root);
	169	tree->leaf_count = be32_to_cpu(head->leaf_count);
	170	tree->leaf_head = be32_to_cpu(head->leaf_head);
	171	tree->leaf_tail = be32_to_cpu(head->leaf_tail);
	172	tree->node_count = be32_to_cpu(head->node_count);
	173	tree->free_nodes = be32_to_cpu(head->free_nodes);
	174	tree->attributes = be32_to_cpu(head->attributes);
	175	tree->node_size = be16_to_cpu(head->node_size);
	176	tree->max_key_len = be16_to_cpu(head->max_key_len);
	177	tree->depth = be16_to_cpu(head->depth);
	178
9250f925 ES	179	/* Verify the tree and set the correct compare function */
	180	switch (id) {
	181	case HFSPLUS_EXT_CNID:
	182	if (tree->max_key_len != HFSPLUS_EXT_KEYLEN - sizeof(u16)) {
d6142673	183	pr_err("invalid extent max_key_len %d\n",
9250f925 ES	184	tree->max_key_len);
	185	goto fail_page;
	186	}
13571a69	187	if (tree->attributes & HFS_TREE_VARIDXKEYS) {
d6142673	188	pr_err("invalid extent btree flag\n");
13571a69 CH	189	goto fail_page;
	190	}
	191
2179d372	192	tree->keycmp = hfsplus_ext_cmp_key;
9250f925 ES	193	break;
	194	case HFSPLUS_CAT_CNID:
	195	if (tree->max_key_len != HFSPLUS_CAT_KEYLEN - sizeof(u16)) {
d6142673	196	pr_err("invalid catalog max_key_len %d\n",
9250f925 ES	197	tree->max_key_len);
	198	goto fail_page;
	199	}
13571a69	200	if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
d6142673	201	pr_err("invalid catalog btree flag\n");
13571a69 CH	202	goto fail_page;
13571a69 CH	203	}
9250f925	204
84adede3	205	if (test_bit(HFSPLUS_SB_HFSX, &HFSPLUS_SB(sb)->flags) &&
2179d372 DE	206	(head->key_type == HFSPLUS_KEY_BINARY))
2179d372 DE	207	tree->keycmp = hfsplus_cat_bin_cmp_key;
d45bce8f	208	else {
2179d372	209	tree->keycmp = hfsplus_cat_case_cmp_key;
84adede3	210	set_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags);
d45bce8f	211	}
9250f925	212	break;
324ef39a VD	213	case HFSPLUS_ATTR_CNID:
324ef39a VD	214	if (tree->max_key_len != HFSPLUS_ATTR_KEYLEN - sizeof(u16)) {
d6142673	215	pr_err("invalid attributes max_key_len %d\n",
324ef39a VD	216	tree->max_key_len);
	217	goto fail_page;
	218	}
	219	tree->keycmp = hfsplus_attr_bin_cmp_key;
	220	break;
9250f925	221	default:
d6142673	222	pr_err("unknown B*Tree requested\n");
2179d372 DE	223	goto fail_page;
	224	}
	225
13571a69	226	if (!(tree->attributes & HFS_TREE_BIGKEYS)) {
d6142673	227	pr_err("invalid btree flag\n");
13571a69 CH	228	goto fail_page;
	229	}
	230
1da177e4	231	size = tree->node_size;
e1b5c1d3	232	if (!is_power_of_2(size))
1da177e4 LT	233	goto fail_page;
	234	if (!tree->node_count)
	235	goto fail_page;
9250f925	236
1da177e4 LT	237	tree->node_size_shift = ffs(size) - 1;
1da177e4 LT	238
2753cc28	239	tree->pages_per_bnode =
09cbfeaf KS	240	(tree->node_size + PAGE_SIZE - 1) >>
09cbfeaf KS	241	PAGE_SHIFT;
1da177e4 LT	242
1da177e4 LT	243	kunmap(page);
09cbfeaf	244	put_page(page);
1da177e4 LT	245	return tree;
	246
	247	fail_page:
09cbfeaf	248	put_page(page);
ee527162	249	free_inode:
9250f925	250	tree->inode->i_mapping->a_ops = &hfsplus_aops;
1da177e4	251	iput(tree->inode);
ee527162	252	free_tree:
1da177e4 LT	253	kfree(tree);
	254	return NULL;
	255	}
	256
	257	/* Release resources used by a btree */
	258	void hfs_btree_close(struct hfs_btree *tree)
	259	{
	260	struct hfs_bnode *node;
	261	int i;
	262
	263	if (!tree)
	264	return;
	265
	266	for (i = 0; i < NODE_HASH_SIZE; i++) {
	267	while ((node = tree->node_hash[i])) {
	268	tree->node_hash[i] = node->next_hash;
	269	if (atomic_read(&node->refcnt))
d6142673	270	pr_crit("node %d:%d "
2753cc28 AS	271	"still has %d user(s)!\n",
	272	node->tree->cnid, node->this,
	273	atomic_read(&node->refcnt));
1da177e4 LT	274	hfs_bnode_free(node);
	275	tree->node_hash_cnt--;
	276	}
	277	}
	278	iput(tree->inode);
	279	kfree(tree);
	280	}
	281
81cc7fad	282	int hfs_btree_write(struct hfs_btree *tree)
1da177e4 LT	283	{
	284	struct hfs_btree_header_rec *head;
	285	struct hfs_bnode *node;
	286	struct page *page;
	287
	288	node = hfs_bnode_find(tree, 0);
	289	if (IS_ERR(node))
	290	/* panic? */
81cc7fad	291	return -EIO;
1da177e4 LT	292	/* Load the header */
1da177e4 LT	293	page = node->page[0];
2753cc28 AS	294	head = (struct hfs_btree_header_rec *)(kmap(page) +
2753cc28 AS	295	sizeof(struct hfs_bnode_desc));
1da177e4 LT	296
	297	head->root = cpu_to_be32(tree->root);
	298	head->leaf_count = cpu_to_be32(tree->leaf_count);
	299	head->leaf_head = cpu_to_be32(tree->leaf_head);
	300	head->leaf_tail = cpu_to_be32(tree->leaf_tail);
	301	head->node_count = cpu_to_be32(tree->node_count);
	302	head->free_nodes = cpu_to_be32(tree->free_nodes);
	303	head->attributes = cpu_to_be32(tree->attributes);
	304	head->depth = cpu_to_be16(tree->depth);
	305
	306	kunmap(page);
	307	set_page_dirty(page);
	308	hfs_bnode_put(node);
81cc7fad	309	return 0;
1da177e4 LT	310	}
	311
	312	static struct hfs_bnode hfs_bmap_new_bmap(struct hfs_bnode prev, u32 idx)
	313	{
	314	struct hfs_btree *tree = prev->tree;
	315	struct hfs_bnode *node;
	316	struct hfs_bnode_desc desc;
	317	__be32 cnid;
	318
	319	node = hfs_bnode_create(tree, idx);
	320	if (IS_ERR(node))
	321	return node;
	322
	323	tree->free_nodes--;
	324	prev->next = idx;
	325	cnid = cpu_to_be32(idx);
	326	hfs_bnode_write(prev, &cnid, offsetof(struct hfs_bnode_desc, next), 4);
	327
	328	node->type = HFS_NODE_MAP;
	329	node->num_recs = 1;
	330	hfs_bnode_clear(node, 0, tree->node_size);
	331	desc.next = 0;
	332	desc.prev = 0;
	333	desc.type = HFS_NODE_MAP;
	334	desc.height = 0;
	335	desc.num_recs = cpu_to_be16(1);
	336	desc.reserved = 0;
	337	hfs_bnode_write(node, &desc, 0, sizeof(desc));
	338	hfs_bnode_write_u16(node, 14, 0x8000);
	339	hfs_bnode_write_u16(node, tree->node_size - 2, 14);
	340	hfs_bnode_write_u16(node, tree->node_size - 4, tree->node_size - 6);
	341
	342	return node;
	343	}
	344
d92915c3 EF	345	/* Make sure @tree has enough space for the @rsvd_nodes */
d92915c3 EF	346	int hfs_bmap_reserve(struct hfs_btree *tree, int rsvd_nodes)
1da177e4	347	{
d92915c3 EF	348	struct inode *inode = tree->inode;
	349	struct hfsplus_inode_info *hip = HFSPLUS_I(inode);
	350	u32 count;
	351	int res;
1da177e4	352
d92915c3 EF	353	if (rsvd_nodes <= 0)
d92915c3 EF	354	return 0;
1da177e4	355
d92915c3	356	while (tree->free_nodes < rsvd_nodes) {
2cd282a1	357	res = hfsplus_file_extend(inode, hfs_bnode_need_zeroout(tree));
1da177e4	358	if (res)
d92915c3	359	return res;
6af502de CH	360	hip->phys_size = inode->i_size =
6af502de CH	361	(loff_t)hip->alloc_blocks <<
dd73a01a	362	HFSPLUS_SB(tree->sb)->alloc_blksz_shift;
6af502de CH	363	hip->fs_blocks =
6af502de CH	364	hip->alloc_blocks << HFSPLUS_SB(tree->sb)->fs_shift;
1da177e4 LT	365	inode_set_bytes(inode, inode->i_size);
1da177e4 LT	366	count = inode->i_size >> tree->node_size_shift;
d92915c3	367	tree->free_nodes += count - tree->node_count;
1da177e4 LT	368	tree->node_count = count;
1da177e4 LT	369	}
d92915c3 EF	370	return 0;
	371	}
	372
	373	struct hfs_bnode hfs_bmap_alloc(struct hfs_btree tree)
	374	{
	375	struct hfs_bnode node, next_node;
	376	struct page **pagep;
	377	u32 nidx, idx;
	378	unsigned off;
	379	u16 off16;
	380	u16 len;
	381	u8 *data, byte, m;
	382	int i, res;
	383
	384	res = hfs_bmap_reserve(tree, 1);
	385	if (res)
	386	return ERR_PTR(res);
1da177e4 LT	387
	388	nidx = 0;
	389	node = hfs_bnode_find(tree, nidx);
	390	if (IS_ERR(node))
	391	return node;
487798df AM	392	len = hfs_brec_lenoff(node, 2, &off16);
487798df AM	393	off = off16;
1da177e4 LT	394
1da177e4 LT	395	off += node->page_offset;
09cbfeaf	396	pagep = node->page + (off >> PAGE_SHIFT);
1da177e4	397	data = kmap(*pagep);
09cbfeaf	398	off &= ~PAGE_MASK;
1da177e4 LT	399	idx = 0;
	400
	401	for (;;) {
	402	while (len) {
	403	byte = data[off];
	404	if (byte != 0xff) {
	405	for (m = 0x80, i = 0; i < 8; m >>= 1, i++) {
	406	if (!(byte & m)) {
	407	idx += i;
	408	data[off] \|= m;
	409	set_page_dirty(*pagep);
	410	kunmap(*pagep);
	411	tree->free_nodes--;
	412	mark_inode_dirty(tree->inode);
	413	hfs_bnode_put(node);
2753cc28 AS	414	return hfs_bnode_create(tree,
2753cc28 AS	415	idx);
1da177e4 LT	416	}
	417	}
	418	}
09cbfeaf	419	if (++off >= PAGE_SIZE) {
1da177e4 LT	420	kunmap(*pagep);
	421	data = kmap(*++pagep);
	422	off = 0;
	423	}
	424	idx += 8;
	425	len--;
	426	}
	427	kunmap(*pagep);
	428	nidx = node->next;
	429	if (!nidx) {
c2b3e1f7	430	hfs_dbg(BNODE_MOD, "create new bmap node\n");
1da177e4 LT	431	next_node = hfs_bmap_new_bmap(node, idx);
	432	} else
	433	next_node = hfs_bnode_find(tree, nidx);
	434	hfs_bnode_put(node);
	435	if (IS_ERR(next_node))
	436	return next_node;
	437	node = next_node;
	438
487798df AM	439	len = hfs_brec_lenoff(node, 0, &off16);
487798df AM	440	off = off16;
1da177e4	441	off += node->page_offset;
09cbfeaf	442	pagep = node->page + (off >> PAGE_SHIFT);
1da177e4	443	data = kmap(*pagep);
09cbfeaf	444	off &= ~PAGE_MASK;
1da177e4 LT	445	}
	446	}
	447
	448	void hfs_bmap_free(struct hfs_bnode *node)
	449	{
	450	struct hfs_btree *tree;
	451	struct page *page;
	452	u16 off, len;
	453	u32 nidx;
	454	u8 *data, byte, m;
	455
c2b3e1f7	456	hfs_dbg(BNODE_MOD, "btree_free_node: %u\n", node->this);
0bf3ba53	457	BUG_ON(!node->this);
1da177e4 LT	458	tree = node->tree;
	459	nidx = node->this;
	460	node = hfs_bnode_find(tree, 0);
	461	if (IS_ERR(node))
	462	return;
	463	len = hfs_brec_lenoff(node, 2, &off);
	464	while (nidx >= len * 8) {
	465	u32 i;
	466
	467	nidx -= len * 8;
	468	i = node->next;
1da177e4 LT	469	if (!i) {
1da177e4 LT	470	/* panic */;
d6142673	471	pr_crit("unable to free bnode %u. "
2753cc28 AS	472	"bmap not found!\n",
2753cc28 AS	473	node->this);
c7d7d620	474	hfs_bnode_put(node);
1da177e4 LT	475	return;
1da177e4 LT	476	}
c7d7d620	477	hfs_bnode_put(node);
1da177e4 LT	478	node = hfs_bnode_find(tree, i);
	479	if (IS_ERR(node))
	480	return;
	481	if (node->type != HFS_NODE_MAP) {
	482	/* panic */;
d6142673	483	pr_crit("invalid bmap found! "
2753cc28 AS	484	"(%u,%d)\n",
2753cc28 AS	485	node->this, node->type);
1da177e4 LT	486	hfs_bnode_put(node);
	487	return;
	488	}
	489	len = hfs_brec_lenoff(node, 0, &off);
	490	}
	491	off += node->page_offset + nidx / 8;
09cbfeaf	492	page = node->page[off >> PAGE_SHIFT];
1da177e4	493	data = kmap(page);
09cbfeaf	494	off &= ~PAGE_MASK;
1da177e4 LT	495	m = 1 << (~nidx & 7);
	496	byte = data[off];
	497	if (!(byte & m)) {
d6142673	498	pr_crit("trying to free free bnode "
2753cc28 AS	499	"%u(%d)\n",
2753cc28 AS	500	node->this, node->type);
1da177e4 LT	501	kunmap(page);
	502	hfs_bnode_put(node);
	503	return;
	504	}
	505	data[off] = byte & ~m;
	506	set_page_dirty(page);
	507	kunmap(page);
	508	hfs_bnode_put(node);
	509	tree->free_nodes++;
	510	mark_inode_dirty(tree->inode);
	511	}