[linux.git] / fs / hfsplus / brec.c

/*
 *  linux/fs/hfsplus/brec.c
 *
 * Copyright (C) 2001
 * Brad Boyer ([email protected])
 * (C) 2003 Ardis Technologies <[email protected]>
 *
 * Handle individual btree records
 */

#include "hfsplus_fs.h"
#include "hfsplus_raw.h"

static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd);
static int hfs_brec_update_parent(struct hfs_find_data *fd);
static int hfs_btree_inc_height(struct hfs_btree *);

/* Get the length and offset of the given record in the given node */
u16 hfs_brec_lenoff(struct hfs_bnode *node, u16 rec, u16 *off)
{
	__be16 retval[2];
	u16 dataoff;

	dataoff = node->tree->node_size - (rec + 2) * 2;
	hfs_bnode_read(node, retval, dataoff, 4);
	*off = be16_to_cpu(retval[1]);
	return be16_to_cpu(retval[0]) - *off;
}

/* Get the length of the key from a keyed record */
u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
{
	u16 retval, recoff;

	if (node->type != HFS_NODE_INDEX && node->type != HFS_NODE_LEAF)
		return 0;

	if ((node->type == HFS_NODE_INDEX) &&
	   !(node->tree->attributes & HFS_TREE_VARIDXKEYS)) {
		retval = node->tree->max_key_len + 2;
	} else {
		recoff = hfs_bnode_read_u16(node,
			node->tree->node_size - (rec + 1) * 2);
		if (!recoff)
			return 0;
		if (recoff > node->tree->node_size - 2) {
			printk(KERN_ERR "hfs: recoff %d too large\n", recoff);
			return 0;
		}

		retval = hfs_bnode_read_u16(node, recoff) + 2;
		if (retval > node->tree->max_key_len + 2) {
			printk(KERN_ERR "hfs: keylen %d too large\n",
				retval);
			retval = 0;
		}
	}
	return retval;
}

int hfs_brec_insert(struct hfs_find_data *fd, void *entry, int entry_len)
{
	struct hfs_btree *tree;
	struct hfs_bnode *node, *new_node;
	int size, key_len, rec;
	int data_off, end_off;
	int idx_rec_off, data_rec_off, end_rec_off;
	__be32 cnid;

	tree = fd->tree;
	if (!fd->bnode) {
		if (!tree->root)
			hfs_btree_inc_height(tree);
		fd->bnode = hfs_bnode_find(tree, tree->leaf_head);
		if (IS_ERR(fd->bnode))
			return PTR_ERR(fd->bnode);
		fd->record = -1;
	}
	new_node = NULL;
	key_len = be16_to_cpu(fd->search_key->key_len) + 2;
again:
	/* new record idx and complete record size */
	rec = fd->record + 1;
	size = key_len + entry_len;

	node = fd->bnode;
	hfs_bnode_dump(node);
	/* get last offset */
	end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
	end_off = hfs_bnode_read_u16(node, end_rec_off);
	end_rec_off -= 2;
	dprint(DBG_BNODE_MOD, "insert_rec: %d, %d, %d, %d\n",
		rec, size, end_off, end_rec_off);
	if (size > end_rec_off - end_off) {
		if (new_node)
			panic("not enough room!\n");
		new_node = hfs_bnode_split(fd);
		if (IS_ERR(new_node))
			return PTR_ERR(new_node);
		goto again;
	}
	if (node->type == HFS_NODE_LEAF) {
		tree->leaf_count++;
		mark_inode_dirty(tree->inode);
	}
	node->num_recs++;
	/* write new last offset */
	hfs_bnode_write_u16(node,
		offsetof(struct hfs_bnode_desc, num_recs),
		node->num_recs);
	hfs_bnode_write_u16(node, end_rec_off, end_off + size);
	data_off = end_off;
	data_rec_off = end_rec_off + 2;
	idx_rec_off = tree->node_size - (rec + 1) * 2;
	if (idx_rec_off == data_rec_off)
		goto skip;
	/* move all following entries */
	do {
		data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
		hfs_bnode_write_u16(node, data_rec_off, data_off + size);
		data_rec_off += 2;
	} while (data_rec_off < idx_rec_off);

	/* move data away */
	hfs_bnode_move(node, data_off + size, data_off,
		       end_off - data_off);

skip:
	hfs_bnode_write(node, fd->search_key, data_off, key_len);
	hfs_bnode_write(node, entry, data_off + key_len, entry_len);
	hfs_bnode_dump(node);

	if (new_node) {
		/* update parent key if we inserted a key
		 * at the start of the first node
		 */
		if (!rec && new_node != node)
			hfs_brec_update_parent(fd);

		hfs_bnode_put(fd->bnode);
		if (!new_node->parent) {
			hfs_btree_inc_height(tree);
			new_node->parent = tree->root;
		}
		fd->bnode = hfs_bnode_find(tree, new_node->parent);

		/* create index data entry */
		cnid = cpu_to_be32(new_node->this);
		entry = &cnid;
		entry_len = sizeof(cnid);

		/* get index key */
		hfs_bnode_read_key(new_node, fd->search_key, 14);
		__hfs_brec_find(fd->bnode, fd);

		hfs_bnode_put(new_node);
		new_node = NULL;

		if (tree->attributes & HFS_TREE_VARIDXKEYS)
			key_len = be16_to_cpu(fd->search_key->key_len) + 2;
		else {
			fd->search_key->key_len =
				cpu_to_be16(tree->max_key_len);
			key_len = tree->max_key_len + 2;
		}
		goto again;
	}

	if (!rec)
		hfs_brec_update_parent(fd);

	return 0;
}

int hfs_brec_remove(struct hfs_find_data *fd)
{
	struct hfs_btree *tree;
	struct hfs_bnode *node, *parent;
	int end_off, rec_off, data_off, size;

	tree = fd->tree;
	node = fd->bnode;
again:
	rec_off = tree->node_size - (fd->record + 2) * 2;
	end_off = tree->node_size - (node->num_recs + 1) * 2;

	if (node->type == HFS_NODE_LEAF) {
		tree->leaf_count--;
		mark_inode_dirty(tree->inode);
	}
	hfs_bnode_dump(node);
	dprint(DBG_BNODE_MOD, "remove_rec: %d, %d\n",
		fd->record, fd->keylength + fd->entrylength);
	if (!--node->num_recs) {
		hfs_bnode_unlink(node);
		if (!node->parent)
			return 0;
		parent = hfs_bnode_find(tree, node->parent);
		if (IS_ERR(parent))
			return PTR_ERR(parent);
		hfs_bnode_put(node);
		node = fd->bnode = parent;

		__hfs_brec_find(node, fd);
		goto again;
	}
	hfs_bnode_write_u16(node,
		offsetof(struct hfs_bnode_desc, num_recs),
		node->num_recs);

	if (rec_off == end_off)
		goto skip;
	size = fd->keylength + fd->entrylength;

	do {
		data_off = hfs_bnode_read_u16(node, rec_off);
		hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
		rec_off -= 2;
	} while (rec_off >= end_off);

	/* fill hole */
	hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
		       data_off - fd->keyoffset - size);
skip:
	hfs_bnode_dump(node);
	if (!fd->record)
		hfs_brec_update_parent(fd);
	return 0;
}

static struct hfs_bnode *hfs_bnode_split(struct hfs_find_data *fd)
{
	struct hfs_btree *tree;
	struct hfs_bnode *node, *new_node, *next_node;
	struct hfs_bnode_desc node_desc;
	int num_recs, new_rec_off, new_off, old_rec_off;
	int data_start, data_end, size;

	tree = fd->tree;
	node = fd->bnode;
	new_node = hfs_bmap_alloc(tree);
	if (IS_ERR(new_node))
		return new_node;
	hfs_bnode_get(node);
	dprint(DBG_BNODE_MOD, "split_nodes: %d - %d - %d\n",
		node->this, new_node->this, node->next);
	new_node->next = node->next;
	new_node->prev = node->this;
	new_node->parent = node->parent;
	new_node->type = node->type;
	new_node->height = node->height;

	if (node->next)
		next_node = hfs_bnode_find(tree, node->next);
	else
		next_node = NULL;

	if (IS_ERR(next_node)) {
		hfs_bnode_put(node);
		hfs_bnode_put(new_node);
		return next_node;
	}

	size = tree->node_size / 2 - node->num_recs * 2 - 14;
	old_rec_off = tree->node_size - 4;
	num_recs = 1;
	for (;;) {
		data_start = hfs_bnode_read_u16(node, old_rec_off);
		if (data_start > size)
			break;
		old_rec_off -= 2;
		if (++num_recs < node->num_recs)
			continue;
		/* panic? */
		hfs_bnode_put(node);
		hfs_bnode_put(new_node);
		if (next_node)
			hfs_bnode_put(next_node);
		return ERR_PTR(-ENOSPC);
	}

	if (fd->record + 1 < num_recs) {
		/* new record is in the lower half,
		 * so leave some more space there
		 */
		old_rec_off += 2;
		num_recs--;
		data_start = hfs_bnode_read_u16(node, old_rec_off);
	} else {
		hfs_bnode_put(node);
		hfs_bnode_get(new_node);
		fd->bnode = new_node;
		fd->record -= num_recs;
		fd->keyoffset -= data_start - 14;
		fd->entryoffset -= data_start - 14;
	}
	new_node->num_recs = node->num_recs - num_recs;
	node->num_recs = num_recs;

	new_rec_off = tree->node_size - 2;
	new_off = 14;
	size = data_start - new_off;
	num_recs = new_node->num_recs;
	data_end = data_start;
	while (num_recs) {
		hfs_bnode_write_u16(new_node, new_rec_off, new_off);
		old_rec_off -= 2;
		new_rec_off -= 2;
		data_end = hfs_bnode_read_u16(node, old_rec_off);
		new_off = data_end - size;
		num_recs--;
	}
	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
	hfs_bnode_copy(new_node, 14, node, data_start, data_end - data_start);

	/* update new bnode header */
	node_desc.next = cpu_to_be32(new_node->next);
	node_desc.prev = cpu_to_be32(new_node->prev);
	node_desc.type = new_node->type;
	node_desc.height = new_node->height;
	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
	node_desc.reserved = 0;
	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));

	/* update previous bnode header */
	node->next = new_node->this;
	hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
	node_desc.next = cpu_to_be32(node->next);
	node_desc.num_recs = cpu_to_be16(node->num_recs);
	hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));

	/* update next bnode header */
	if (next_node) {
		next_node->prev = new_node->this;
		hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
		node_desc.prev = cpu_to_be32(next_node->prev);
		hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
		hfs_bnode_put(next_node);
	} else if (node->this == tree->leaf_tail) {
		/* if there is no next node, this might be the new tail */
		tree->leaf_tail = new_node->this;
		mark_inode_dirty(tree->inode);
	}

	hfs_bnode_dump(node);
	hfs_bnode_dump(new_node);
	hfs_bnode_put(node);

	return new_node;
}

static int hfs_brec_update_parent(struct hfs_find_data *fd)
{
	struct hfs_btree *tree;
	struct hfs_bnode *node, *new_node, *parent;
	int newkeylen, diff;
	int rec, rec_off, end_rec_off;
	int start_off, end_off;

	tree = fd->tree;
	node = fd->bnode;
	new_node = NULL;
	if (!node->parent)
		return 0;

again:
	parent = hfs_bnode_find(tree, node->parent);
	if (IS_ERR(parent))
		return PTR_ERR(parent);
	__hfs_brec_find(parent, fd);
	hfs_bnode_dump(parent);
	rec = fd->record;

	/* size difference between old and new key */
	if (tree->attributes & HFS_TREE_VARIDXKEYS)
		newkeylen = hfs_bnode_read_u16(node, 14) + 2;
	else
		fd->keylength = newkeylen = tree->max_key_len + 2;
	dprint(DBG_BNODE_MOD, "update_rec: %d, %d, %d\n",
		rec, fd->keylength, newkeylen);

	rec_off = tree->node_size - (rec + 2) * 2;
	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
	diff = newkeylen - fd->keylength;
	if (!diff)
		goto skip;
	if (diff > 0) {
		end_off = hfs_bnode_read_u16(parent, end_rec_off);
		if (end_rec_off - end_off < diff) {

			dprint(DBG_BNODE_MOD, "hfs: splitting index node.\n");
			fd->bnode = parent;
			new_node = hfs_bnode_split(fd);
			if (IS_ERR(new_node))
				return PTR_ERR(new_node);
			parent = fd->bnode;
			rec = fd->record;
			rec_off = tree->node_size - (rec + 2) * 2;
			end_rec_off = tree->node_size -
				(parent->num_recs + 1) * 2;
		}
	}

	end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
	hfs_bnode_write_u16(parent, rec_off, start_off + diff);
	start_off -= 4;	/* move previous cnid too */

	while (rec_off > end_rec_off) {
		rec_off -= 2;
		end_off = hfs_bnode_read_u16(parent, rec_off);
		hfs_bnode_write_u16(parent, rec_off, end_off + diff);
	}
	hfs_bnode_move(parent, start_off + diff, start_off,
		       end_off - start_off);
skip:
	hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
	hfs_bnode_dump(parent);

	hfs_bnode_put(node);
	node = parent;

	if (new_node) {
		__be32 cnid;

		fd->bnode = hfs_bnode_find(tree, new_node->parent);
		/* create index key and entry */
		hfs_bnode_read_key(new_node, fd->search_key, 14);
		cnid = cpu_to_be32(new_node->this);

		__hfs_brec_find(fd->bnode, fd);
		hfs_brec_insert(fd, &cnid, sizeof(cnid));
		hfs_bnode_put(fd->bnode);
		hfs_bnode_put(new_node);

		if (!rec) {
			if (new_node == node)
				goto out;
			/* restore search_key */
			hfs_bnode_read_key(node, fd->search_key, 14);
		}
	}

	if (!rec && node->parent)
		goto again;
out:
	fd->bnode = node;
	return 0;
}

static int hfs_btree_inc_height(struct hfs_btree *tree)
{
	struct hfs_bnode *node, *new_node;
	struct hfs_bnode_desc node_desc;
	int key_size, rec;
	__be32 cnid;

	node = NULL;
	if (tree->root) {
		node = hfs_bnode_find(tree, tree->root);
		if (IS_ERR(node))
			return PTR_ERR(node);
	}
	new_node = hfs_bmap_alloc(tree);
	if (IS_ERR(new_node)) {
		hfs_bnode_put(node);
		return PTR_ERR(new_node);
	}

	tree->root = new_node->this;
	if (!tree->depth) {
		tree->leaf_head = tree->leaf_tail = new_node->this;
		new_node->type = HFS_NODE_LEAF;
		new_node->num_recs = 0;
	} else {
		new_node->type = HFS_NODE_INDEX;
		new_node->num_recs = 1;
	}
	new_node->parent = 0;
	new_node->next = 0;
	new_node->prev = 0;
	new_node->height = ++tree->depth;

	node_desc.next = cpu_to_be32(new_node->next);
	node_desc.prev = cpu_to_be32(new_node->prev);
	node_desc.type = new_node->type;
	node_desc.height = new_node->height;
	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
	node_desc.reserved = 0;
	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));

	rec = tree->node_size - 2;
	hfs_bnode_write_u16(new_node, rec, 14);

	if (node) {
		/* insert old root idx into new root */
		node->parent = tree->root;
		if (node->type == HFS_NODE_LEAF ||
		    tree->attributes & HFS_TREE_VARIDXKEYS)
			key_size = hfs_bnode_read_u16(node, 14) + 2;
		else
			key_size = tree->max_key_len + 2;
		hfs_bnode_copy(new_node, 14, node, 14, key_size);

		if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
			key_size = tree->max_key_len + 2;
			hfs_bnode_write_u16(new_node, 14, tree->max_key_len);
		}
		cnid = cpu_to_be32(node->this);
		hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);

		rec -= 2;
		hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);

		hfs_bnode_put(node);
	}
	hfs_bnode_put(new_node);
	mark_inode_dirty(tree->inode);

	return 0;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/hfsplus/brec.c
	3	*
	4	* Copyright (C) 2001
	5	* Brad Boyer ([email protected])
	6	* (C) 2003 Ardis Technologies <[email protected]>
	7	*
	8	* Handle individual btree records
	9	*/
	10
	11	#include "hfsplus_fs.h"
	12	#include "hfsplus_raw.h"
	13
	14	static struct hfs_bnode hfs_bnode_split(struct hfs_find_data fd);
	15	static int hfs_brec_update_parent(struct hfs_find_data *fd);
	16	static int hfs_btree_inc_height(struct hfs_btree *);
	17
	18	/* Get the length and offset of the given record in the given node */
	19	u16 hfs_brec_lenoff(struct hfs_bnode node, u16 rec, u16 off)
	20	{
	21	__be16 retval[2];
	22	u16 dataoff;
	23
	24	dataoff = node->tree->node_size - (rec + 2) * 2;
	25	hfs_bnode_read(node, retval, dataoff, 4);
	26	*off = be16_to_cpu(retval[1]);
	27	return be16_to_cpu(retval[0]) - *off;
	28	}
	29
	30	/* Get the length of the key from a keyed record */
	31	u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
	32	{
	33	u16 retval, recoff;
	34
	35	if (node->type != HFS_NODE_INDEX && node->type != HFS_NODE_LEAF)
	36	return 0;
	37
	38	if ((node->type == HFS_NODE_INDEX) &&
	39	!(node->tree->attributes & HFS_TREE_VARIDXKEYS)) {
	40	retval = node->tree->max_key_len + 2;
	41	} else {
2753cc28 AS	42	recoff = hfs_bnode_read_u16(node,
2753cc28 AS	43	node->tree->node_size - (rec + 1) * 2);
1da177e4 LT	44	if (!recoff)
1da177e4 LT	45	return 0;
aac4e419 NA	46	if (recoff > node->tree->node_size - 2) {
	47	printk(KERN_ERR "hfs: recoff %d too large\n", recoff);
	48	return 0;
	49	}
13571a69 CH	50
	51	retval = hfs_bnode_read_u16(node, recoff) + 2;
	52	if (retval > node->tree->max_key_len + 2) {
	53	printk(KERN_ERR "hfs: keylen %d too large\n",
	54	retval);
	55	retval = 0;
9250f925	56	}
1da177e4 LT	57	}
	58	return retval;
	59	}
	60
	61	int hfs_brec_insert(struct hfs_find_data fd, void entry, int entry_len)
	62	{
	63	struct hfs_btree *tree;
	64	struct hfs_bnode node, new_node;
	65	int size, key_len, rec;
	66	int data_off, end_off;
	67	int idx_rec_off, data_rec_off, end_rec_off;
	68	__be32 cnid;
	69
	70	tree = fd->tree;
	71	if (!fd->bnode) {
	72	if (!tree->root)
	73	hfs_btree_inc_height(tree);
	74	fd->bnode = hfs_bnode_find(tree, tree->leaf_head);
	75	if (IS_ERR(fd->bnode))
	76	return PTR_ERR(fd->bnode);
	77	fd->record = -1;
	78	}
	79	new_node = NULL;
	80	key_len = be16_to_cpu(fd->search_key->key_len) + 2;
	81	again:
	82	/* new record idx and complete record size */
	83	rec = fd->record + 1;
	84	size = key_len + entry_len;
	85
	86	node = fd->bnode;
	87	hfs_bnode_dump(node);
	88	/* get last offset */
	89	end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
	90	end_off = hfs_bnode_read_u16(node, end_rec_off);
	91	end_rec_off -= 2;
2753cc28 AS	92	dprint(DBG_BNODE_MOD, "insert_rec: %d, %d, %d, %d\n",
2753cc28 AS	93	rec, size, end_off, end_rec_off);
1da177e4 LT	94	if (size > end_rec_off - end_off) {
	95	if (new_node)
	96	panic("not enough room!\n");
	97	new_node = hfs_bnode_split(fd);
	98	if (IS_ERR(new_node))
	99	return PTR_ERR(new_node);
	100	goto again;
	101	}
	102	if (node->type == HFS_NODE_LEAF) {
	103	tree->leaf_count++;
	104	mark_inode_dirty(tree->inode);
	105	}
	106	node->num_recs++;
	107	/* write new last offset */
2753cc28 AS	108	hfs_bnode_write_u16(node,
	109	offsetof(struct hfs_bnode_desc, num_recs),
	110	node->num_recs);
1da177e4 LT	111	hfs_bnode_write_u16(node, end_rec_off, end_off + size);
	112	data_off = end_off;
	113	data_rec_off = end_rec_off + 2;
	114	idx_rec_off = tree->node_size - (rec + 1) * 2;
	115	if (idx_rec_off == data_rec_off)
	116	goto skip;
	117	/* move all following entries */
	118	do {
	119	data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
	120	hfs_bnode_write_u16(node, data_rec_off, data_off + size);
	121	data_rec_off += 2;
	122	} while (data_rec_off < idx_rec_off);
	123
	124	/* move data away */
	125	hfs_bnode_move(node, data_off + size, data_off,
	126	end_off - data_off);
	127
	128	skip:
	129	hfs_bnode_write(node, fd->search_key, data_off, key_len);
	130	hfs_bnode_write(node, entry, data_off + key_len, entry_len);
	131	hfs_bnode_dump(node);
	132
	133	if (new_node) {
	134	/* update parent key if we inserted a key
	135	* at the start of the first node
	136	*/
	137	if (!rec && new_node != node)
	138	hfs_brec_update_parent(fd);
	139
	140	hfs_bnode_put(fd->bnode);
	141	if (!new_node->parent) {
	142	hfs_btree_inc_height(tree);
	143	new_node->parent = tree->root;
	144	}
	145	fd->bnode = hfs_bnode_find(tree, new_node->parent);
	146
	147	/* create index data entry */
	148	cnid = cpu_to_be32(new_node->this);
	149	entry = &cnid;
	150	entry_len = sizeof(cnid);
	151
	152	/* get index key */
	153	hfs_bnode_read_key(new_node, fd->search_key, 14);
	154	__hfs_brec_find(fd->bnode, fd);
	155
	156	hfs_bnode_put(new_node);
	157	new_node = NULL;
	158
	159	if (tree->attributes & HFS_TREE_VARIDXKEYS)
	160	key_len = be16_to_cpu(fd->search_key->key_len) + 2;
	161	else {
2753cc28 AS	162	fd->search_key->key_len =
2753cc28 AS	163	cpu_to_be16(tree->max_key_len);
1da177e4 LT	164	key_len = tree->max_key_len + 2;
	165	}
	166	goto again;
	167	}
	168
	169	if (!rec)
	170	hfs_brec_update_parent(fd);
	171
	172	return 0;
	173	}
	174
	175	int hfs_brec_remove(struct hfs_find_data *fd)
	176	{
	177	struct hfs_btree *tree;
	178	struct hfs_bnode node, parent;
	179	int end_off, rec_off, data_off, size;
	180
	181	tree = fd->tree;
	182	node = fd->bnode;
	183	again:
	184	rec_off = tree->node_size - (fd->record + 2) * 2;
	185	end_off = tree->node_size - (node->num_recs + 1) * 2;
	186
	187	if (node->type == HFS_NODE_LEAF) {
	188	tree->leaf_count--;
	189	mark_inode_dirty(tree->inode);
	190	}
	191	hfs_bnode_dump(node);
2753cc28 AS	192	dprint(DBG_BNODE_MOD, "remove_rec: %d, %d\n",
2753cc28 AS	193	fd->record, fd->keylength + fd->entrylength);
1da177e4 LT	194	if (!--node->num_recs) {
	195	hfs_bnode_unlink(node);
	196	if (!node->parent)
	197	return 0;
	198	parent = hfs_bnode_find(tree, node->parent);
	199	if (IS_ERR(parent))
	200	return PTR_ERR(parent);
	201	hfs_bnode_put(node);
	202	node = fd->bnode = parent;
	203
	204	__hfs_brec_find(node, fd);
	205	goto again;
	206	}
2753cc28 AS	207	hfs_bnode_write_u16(node,
	208	offsetof(struct hfs_bnode_desc, num_recs),
	209	node->num_recs);
1da177e4 LT	210
	211	if (rec_off == end_off)
	212	goto skip;
	213	size = fd->keylength + fd->entrylength;
	214
	215	do {
	216	data_off = hfs_bnode_read_u16(node, rec_off);
	217	hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
	218	rec_off -= 2;
	219	} while (rec_off >= end_off);
	220
	221	/* fill hole */
	222	hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
	223	data_off - fd->keyoffset - size);
	224	skip:
	225	hfs_bnode_dump(node);
	226	if (!fd->record)
	227	hfs_brec_update_parent(fd);
	228	return 0;
	229	}
	230
	231	static struct hfs_bnode hfs_bnode_split(struct hfs_find_data fd)
	232	{
	233	struct hfs_btree *tree;
b6b41424	234	struct hfs_bnode node, new_node, *next_node;
1da177e4 LT	235	struct hfs_bnode_desc node_desc;
	236	int num_recs, new_rec_off, new_off, old_rec_off;
	237	int data_start, data_end, size;
	238
	239	tree = fd->tree;
	240	node = fd->bnode;
	241	new_node = hfs_bmap_alloc(tree);
	242	if (IS_ERR(new_node))
	243	return new_node;
	244	hfs_bnode_get(node);
	245	dprint(DBG_BNODE_MOD, "split_nodes: %d - %d - %d\n",
	246	node->this, new_node->this, node->next);
	247	new_node->next = node->next;
	248	new_node->prev = node->this;
	249	new_node->parent = node->parent;
	250	new_node->type = node->type;
	251	new_node->height = node->height;
	252
b6b41424 AV	253	if (node->next)
	254	next_node = hfs_bnode_find(tree, node->next);
	255	else
	256	next_node = NULL;
	257
	258	if (IS_ERR(next_node)) {
	259	hfs_bnode_put(node);
	260	hfs_bnode_put(new_node);
	261	return next_node;
	262	}
	263
1da177e4 LT	264	size = tree->node_size / 2 - node->num_recs * 2 - 14;
	265	old_rec_off = tree->node_size - 4;
	266	num_recs = 1;
	267	for (;;) {
	268	data_start = hfs_bnode_read_u16(node, old_rec_off);
	269	if (data_start > size)
	270	break;
	271	old_rec_off -= 2;
	272	if (++num_recs < node->num_recs)
	273	continue;
	274	/* panic? */
	275	hfs_bnode_put(node);
	276	hfs_bnode_put(new_node);
b6b41424 AV	277	if (next_node)
b6b41424 AV	278	hfs_bnode_put(next_node);
1da177e4 LT	279	return ERR_PTR(-ENOSPC);
	280	}
	281
	282	if (fd->record + 1 < num_recs) {
	283	/* new record is in the lower half,
	284	* so leave some more space there
	285	*/
	286	old_rec_off += 2;
	287	num_recs--;
	288	data_start = hfs_bnode_read_u16(node, old_rec_off);
	289	} else {
	290	hfs_bnode_put(node);
	291	hfs_bnode_get(new_node);
	292	fd->bnode = new_node;
	293	fd->record -= num_recs;
	294	fd->keyoffset -= data_start - 14;
	295	fd->entryoffset -= data_start - 14;
	296	}
	297	new_node->num_recs = node->num_recs - num_recs;
	298	node->num_recs = num_recs;
	299
	300	new_rec_off = tree->node_size - 2;
	301	new_off = 14;
	302	size = data_start - new_off;
	303	num_recs = new_node->num_recs;
	304	data_end = data_start;
	305	while (num_recs) {
	306	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
	307	old_rec_off -= 2;
	308	new_rec_off -= 2;
	309	data_end = hfs_bnode_read_u16(node, old_rec_off);
	310	new_off = data_end - size;
	311	num_recs--;
	312	}
	313	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
	314	hfs_bnode_copy(new_node, 14, node, data_start, data_end - data_start);
	315
	316	/* update new bnode header */
	317	node_desc.next = cpu_to_be32(new_node->next);
	318	node_desc.prev = cpu_to_be32(new_node->prev);
	319	node_desc.type = new_node->type;
	320	node_desc.height = new_node->height;
	321	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
	322	node_desc.reserved = 0;
	323	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
	324
	325	/* update previous bnode header */
	326	node->next = new_node->this;
	327	hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
	328	node_desc.next = cpu_to_be32(node->next);
	329	node_desc.num_recs = cpu_to_be16(node->num_recs);
	330	hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));
	331
	332	/* update next bnode header */
b6b41424	333	if (next_node) {
1da177e4 LT	334	next_node->prev = new_node->this;
	335	hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
	336	node_desc.prev = cpu_to_be32(next_node->prev);
	337	hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
	338	hfs_bnode_put(next_node);
	339	} else if (node->this == tree->leaf_tail) {
	340	/* if there is no next node, this might be the new tail */
	341	tree->leaf_tail = new_node->this;
	342	mark_inode_dirty(tree->inode);
	343	}
	344
	345	hfs_bnode_dump(node);
	346	hfs_bnode_dump(new_node);
	347	hfs_bnode_put(node);
	348
	349	return new_node;
	350	}
	351
	352	static int hfs_brec_update_parent(struct hfs_find_data *fd)
	353	{
	354	struct hfs_btree *tree;
	355	struct hfs_bnode node, new_node, *parent;
	356	int newkeylen, diff;
	357	int rec, rec_off, end_rec_off;
	358	int start_off, end_off;
	359
	360	tree = fd->tree;
	361	node = fd->bnode;
	362	new_node = NULL;
	363	if (!node->parent)
	364	return 0;
	365
	366	again:
	367	parent = hfs_bnode_find(tree, node->parent);
	368	if (IS_ERR(parent))
	369	return PTR_ERR(parent);
	370	__hfs_brec_find(parent, fd);
	371	hfs_bnode_dump(parent);
	372	rec = fd->record;
	373
	374	/* size difference between old and new key */
	375	if (tree->attributes & HFS_TREE_VARIDXKEYS)
	376	newkeylen = hfs_bnode_read_u16(node, 14) + 2;
	377	else
	378	fd->keylength = newkeylen = tree->max_key_len + 2;
2753cc28 AS	379	dprint(DBG_BNODE_MOD, "update_rec: %d, %d, %d\n",
2753cc28 AS	380	rec, fd->keylength, newkeylen);
1da177e4 LT	381
	382	rec_off = tree->node_size - (rec + 2) * 2;
	383	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
	384	diff = newkeylen - fd->keylength;
	385	if (!diff)
	386	goto skip;
	387	if (diff > 0) {
	388	end_off = hfs_bnode_read_u16(parent, end_rec_off);
	389	if (end_rec_off - end_off < diff) {
	390
6d1bbfc4	391	dprint(DBG_BNODE_MOD, "hfs: splitting index node.\n");
1da177e4 LT	392	fd->bnode = parent;
	393	new_node = hfs_bnode_split(fd);
	394	if (IS_ERR(new_node))
	395	return PTR_ERR(new_node);
	396	parent = fd->bnode;
	397	rec = fd->record;
	398	rec_off = tree->node_size - (rec + 2) * 2;
2753cc28 AS	399	end_rec_off = tree->node_size -
2753cc28 AS	400	(parent->num_recs + 1) * 2;
1da177e4 LT	401	}
	402	}
	403
	404	end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
	405	hfs_bnode_write_u16(parent, rec_off, start_off + diff);
	406	start_off -= 4; /* move previous cnid too */
	407
	408	while (rec_off > end_rec_off) {
	409	rec_off -= 2;
	410	end_off = hfs_bnode_read_u16(parent, rec_off);
	411	hfs_bnode_write_u16(parent, rec_off, end_off + diff);
	412	}
	413	hfs_bnode_move(parent, start_off + diff, start_off,
	414	end_off - start_off);
	415	skip:
	416	hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
	417	hfs_bnode_dump(parent);
	418
	419	hfs_bnode_put(node);
	420	node = parent;
	421
	422	if (new_node) {
	423	__be32 cnid;
	424
	425	fd->bnode = hfs_bnode_find(tree, new_node->parent);
	426	/* create index key and entry */
	427	hfs_bnode_read_key(new_node, fd->search_key, 14);
	428	cnid = cpu_to_be32(new_node->this);
	429
	430	__hfs_brec_find(fd->bnode, fd);
	431	hfs_brec_insert(fd, &cnid, sizeof(cnid));
	432	hfs_bnode_put(fd->bnode);
	433	hfs_bnode_put(new_node);
	434
	435	if (!rec) {
	436	if (new_node == node)
	437	goto out;
	438	/* restore search_key */
	439	hfs_bnode_read_key(node, fd->search_key, 14);
	440	}
	441	}
	442
	443	if (!rec && node->parent)
	444	goto again;
	445	out:
	446	fd->bnode = node;
	447	return 0;
	448	}
	449
	450	static int hfs_btree_inc_height(struct hfs_btree *tree)
	451	{
	452	struct hfs_bnode node, new_node;
	453	struct hfs_bnode_desc node_desc;
	454	int key_size, rec;
	455	__be32 cnid;
	456
	457	node = NULL;
	458	if (tree->root) {
	459	node = hfs_bnode_find(tree, tree->root);
	460	if (IS_ERR(node))
	461	return PTR_ERR(node);
	462	}
	463	new_node = hfs_bmap_alloc(tree);
	464	if (IS_ERR(new_node)) {
465	hfs_bnode_put(node);
466	return PTR_ERR(new_node);
467	}
468
469	tree->root = new_node->this;
470	if (!tree->depth) {
471	tree->leaf_head = tree->leaf_tail = new_node->this;
472	new_node->type = HFS_NODE_LEAF;
473	new_node->num_recs = 0;
474	} else {
475	new_node->type = HFS_NODE_INDEX;
476	new_node->num_recs = 1;
477	}
478	new_node->parent = 0;
479	new_node->next = 0;
480	new_node->prev = 0;
481	new_node->height = ++tree->depth;
482
483	node_desc.next = cpu_to_be32(new_node->next);
484	node_desc.prev = cpu_to_be32(new_node->prev);
485	node_desc.type = new_node->type;
486	node_desc.height = new_node->height;
487	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
488	node_desc.reserved = 0;
489	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
490
491	rec = tree->node_size - 2;
492	hfs_bnode_write_u16(new_node, rec, 14);
493
494	if (node) {
495	/* insert old root idx into new root */
496	node->parent = tree->root;
497	if (node->type == HFS_NODE_LEAF \|\|
498	tree->attributes & HFS_TREE_VARIDXKEYS)
499	key_size = hfs_bnode_read_u16(node, 14) + 2;
500	else
501	key_size = tree->max_key_len + 2;
502	hfs_bnode_copy(new_node, 14, node, 14, key_size);
503
504	if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
505	key_size = tree->max_key_len + 2;
506	hfs_bnode_write_u16(new_node, 14, tree->max_key_len);
507	}
508	cnid = cpu_to_be32(node->this);
509	hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);
510
511	rec -= 2;
512	hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);
513
514	hfs_bnode_put(node);
515	}
516	hfs_bnode_put(new_node);
517	mark_inode_dirty(tree->inode);
518
519	return 0;
520	}