[mirror_ubuntu-hirsute-kernel.git] / fs / hfs / brec.c

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

#include "btree.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 *tree);

/* 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)) {
		if (node->tree->attributes & HFS_TREE_BIGKEYS)
			retval = node->tree->max_key_len + 2;
		else
			retval = node->tree->max_key_len + 1;
	} else {
		recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
		if (!recoff)
			return 0;
		if (node->tree->attributes & HFS_TREE_BIGKEYS) {
			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;
			}
		} else {
			retval = (hfs_bnode_read_u8(node, recoff) | 1) + 1;
			if (retval > node->tree->max_key_len + 1) {
				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 = (fd->search_key->key_len | 1) + 1;
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 = fd->search_key->key_len + 1;
		else {
			fd->search_key->key_len = tree->max_key_len;
			key_len = tree->max_key_len + 1;
		}
		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;
	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;

	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);
		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 (new_node->next) {
		struct hfs_bnode *next_node = hfs_bnode_find(tree, new_node->next);
		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_u8(node, 14) | 1) + 1;
	else
		fd->keylength = newkeylen = tree->max_key_len + 1;
	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) {

			printk(KERN_DEBUG "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);
	if (!(tree->attributes & HFS_TREE_VARIDXKEYS))
		hfs_bnode_write_u8(parent, fd->keyoffset, newkeylen - 1);
	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_u8(node, 14) + 1;
		else
			key_size = tree->max_key_len + 1;
		hfs_bnode_copy(new_node, 14, node, 14, key_size);

		if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
			key_size = tree->max_key_len + 1;
			hfs_bnode_write_u8(new_node, 14, tree->max_key_len);
		}
		key_size = (key_size + 1) & -2;
		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/hfs/brec.c
	3	*
	4	* Copyright (C) 2001
	5	* Brad Boyer (flar@allandria.com)
	6	* (C) 2003 Ardis Technologies <roman@ardistech.com>
	7	*
	8	* Handle individual btree records
	9	*/
	10
	11	#include "btree.h"
	12
	13	static struct hfs_bnode hfs_bnode_split(struct hfs_find_data fd);
	14	static int hfs_brec_update_parent(struct hfs_find_data *fd);
	15	static int hfs_btree_inc_height(struct hfs_btree *tree);
	16
	17	/* Get the length and offset of the given record in the given node */
	18	u16 hfs_brec_lenoff(struct hfs_bnode node, u16 rec, u16 off)
	19	{
	20	__be16 retval[2];
	21	u16 dataoff;
	22
	23	dataoff = node->tree->node_size - (rec + 2) * 2;
	24	hfs_bnode_read(node, retval, dataoff, 4);
	25	*off = be16_to_cpu(retval[1]);
	26	return be16_to_cpu(retval[0]) - *off;
	27	}
	28
	29	/* Get the length of the key from a keyed record */
	30	u16 hfs_brec_keylen(struct hfs_bnode *node, u16 rec)
	31	{
	32	u16 retval, recoff;
	33
	34	if (node->type != HFS_NODE_INDEX && node->type != HFS_NODE_LEAF)
	35	return 0;
	36
	37	if ((node->type == HFS_NODE_INDEX) &&
	38	!(node->tree->attributes & HFS_TREE_VARIDXKEYS)) {
	39	if (node->tree->attributes & HFS_TREE_BIGKEYS)
	40	retval = node->tree->max_key_len + 2;
	41	else
	42	retval = node->tree->max_key_len + 1;
	43	} else {
	44	recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
	45	if (!recoff)
	46	return 0;
cf059462	47	if (node->tree->attributes & HFS_TREE_BIGKEYS) {
1da177e4	48	retval = hfs_bnode_read_u16(node, recoff) + 2;
cf059462 ES	49	if (retval > node->tree->max_key_len + 2) {
	50	printk(KERN_ERR "hfs: keylen %d too large\n",
	51	retval);
55581d01	52	retval = 0;
cf059462 ES	53	}
cf059462 ES	54	} else {
1da177e4	55	retval = (hfs_bnode_read_u8(node, recoff) \| 1) + 1;
cf059462 ES	56	if (retval > node->tree->max_key_len + 1) {
	57	printk(KERN_ERR "hfs: keylen %d too large\n",
	58	retval);
55581d01	59	retval = 0;
cf059462 ES	60	}
cf059462 ES	61	}
1da177e4 LT	62	}
	63	return retval;
	64	}
	65
	66	int hfs_brec_insert(struct hfs_find_data fd, void entry, int entry_len)
	67	{
	68	struct hfs_btree *tree;
	69	struct hfs_bnode node, new_node;
	70	int size, key_len, rec;
	71	int data_off, end_off;
	72	int idx_rec_off, data_rec_off, end_rec_off;
	73	__be32 cnid;
	74
	75	tree = fd->tree;
	76	if (!fd->bnode) {
	77	if (!tree->root)
	78	hfs_btree_inc_height(tree);
	79	fd->bnode = hfs_bnode_find(tree, tree->leaf_head);
	80	if (IS_ERR(fd->bnode))
	81	return PTR_ERR(fd->bnode);
	82	fd->record = -1;
	83	}
	84	new_node = NULL;
	85	key_len = (fd->search_key->key_len \| 1) + 1;
	86	again:
	87	/* new record idx and complete record size */
	88	rec = fd->record + 1;
	89	size = key_len + entry_len;
	90
	91	node = fd->bnode;
	92	hfs_bnode_dump(node);
	93	/* get last offset */
	94	end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
	95	end_off = hfs_bnode_read_u16(node, end_rec_off);
	96	end_rec_off -= 2;
	97	dprint(DBG_BNODE_MOD, "insert_rec: %d, %d, %d, %d\n", rec, size, end_off, end_rec_off);
	98	if (size > end_rec_off - end_off) {
	99	if (new_node)
	100	panic("not enough room!\n");
	101	new_node = hfs_bnode_split(fd);
	102	if (IS_ERR(new_node))
	103	return PTR_ERR(new_node);
	104	goto again;
	105	}
	106	if (node->type == HFS_NODE_LEAF) {
	107	tree->leaf_count++;
	108	mark_inode_dirty(tree->inode);
	109	}
	110	node->num_recs++;
	111	/* write new last offset */
	112	hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
	113	hfs_bnode_write_u16(node, end_rec_off, end_off + size);
	114	data_off = end_off;
	115	data_rec_off = end_rec_off + 2;
	116	idx_rec_off = tree->node_size - (rec + 1) * 2;
	117	if (idx_rec_off == data_rec_off)
	118	goto skip;
	119	/* move all following entries */
	120	do {
	121	data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
	122	hfs_bnode_write_u16(node, data_rec_off, data_off + size);
	123	data_rec_off += 2;
	124	} while (data_rec_off < idx_rec_off);
	125
126	/* move data away */
127	hfs_bnode_move(node, data_off + size, data_off,
128	end_off - data_off);
129
130	skip:
131	hfs_bnode_write(node, fd->search_key, data_off, key_len);
132	hfs_bnode_write(node, entry, data_off + key_len, entry_len);
133	hfs_bnode_dump(node);
134
135	if (new_node) {
136	/* update parent key if we inserted a key
137	* at the start of the first node
138	*/
139	if (!rec && new_node != node)
140	hfs_brec_update_parent(fd);
141
142	hfs_bnode_put(fd->bnode);
143	if (!new_node->parent) {
144	hfs_btree_inc_height(tree);
145	new_node->parent = tree->root;
146	}
147	fd->bnode = hfs_bnode_find(tree, new_node->parent);
148
149	/* create index data entry */
150	cnid = cpu_to_be32(new_node->this);
151	entry = &cnid;
152	entry_len = sizeof(cnid);
153
154	/* get index key */
155	hfs_bnode_read_key(new_node, fd->search_key, 14);
156	__hfs_brec_find(fd->bnode, fd);
157
158	hfs_bnode_put(new_node);
159	new_node = NULL;
160
161	if (tree->attributes & HFS_TREE_VARIDXKEYS)
162	key_len = fd->search_key->key_len + 1;
163	else {
164	fd->search_key->key_len = tree->max_key_len;
165	key_len = tree->max_key_len + 1;
166	}
167	goto again;
168	}
169
170	if (!rec)
171	hfs_brec_update_parent(fd);
172
173	return 0;
174	}
175
176	int hfs_brec_remove(struct hfs_find_data *fd)
177	{
178	struct hfs_btree *tree;
179	struct hfs_bnode node, parent;
180	int end_off, rec_off, data_off, size;
181
182	tree = fd->tree;
183	node = fd->bnode;
184	again:
185	rec_off = tree->node_size - (fd->record + 2) * 2;
186	end_off = tree->node_size - (node->num_recs + 1) * 2;
187
188	if (node->type == HFS_NODE_LEAF) {
189	tree->leaf_count--;
190	mark_inode_dirty(tree->inode);
191	}
192	hfs_bnode_dump(node);
193	dprint(DBG_BNODE_MOD, "remove_rec: %d, %d\n", fd->record, fd->keylength + fd->entrylength);
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	}
207	hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
208
209	if (rec_off == end_off)
210	goto skip;
211	size = fd->keylength + fd->entrylength;
212
213	do {
214	data_off = hfs_bnode_read_u16(node, rec_off);
215	hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
216	rec_off -= 2;
217	} while (rec_off >= end_off);
218
219	/* fill hole */
220	hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
221	data_off - fd->keyoffset - size);
222	skip:
223	hfs_bnode_dump(node);
224	if (!fd->record)
225	hfs_brec_update_parent(fd);
226	return 0;
227	}
228
229	static struct hfs_bnode hfs_bnode_split(struct hfs_find_data fd)
230	{
231	struct hfs_btree *tree;
232	struct hfs_bnode node, new_node;
233	struct hfs_bnode_desc node_desc;
234	int num_recs, new_rec_off, new_off, old_rec_off;
235	int data_start, data_end, size;
236
237	tree = fd->tree;
238	node = fd->bnode;
239	new_node = hfs_bmap_alloc(tree);
240	if (IS_ERR(new_node))
241	return new_node;
242	hfs_bnode_get(node);
243	dprint(DBG_BNODE_MOD, "split_nodes: %d - %d - %d\n",
244	node->this, new_node->this, node->next);
245	new_node->next = node->next;
246	new_node->prev = node->this;
247	new_node->parent = node->parent;
248	new_node->type = node->type;
249	new_node->height = node->height;
250
251	size = tree->node_size / 2 - node->num_recs * 2 - 14;
252	old_rec_off = tree->node_size - 4;
253	num_recs = 1;
254	for (;;) {
255	data_start = hfs_bnode_read_u16(node, old_rec_off);
256	if (data_start > size)
257	break;
258	old_rec_off -= 2;
259	if (++num_recs < node->num_recs)
260	continue;
261	/* panic? */
262	hfs_bnode_put(node);
263	hfs_bnode_put(new_node);
264	return ERR_PTR(-ENOSPC);
265	}
266
267	if (fd->record + 1 < num_recs) {
268	/* new record is in the lower half,
269	* so leave some more space there
270	*/
271	old_rec_off += 2;
272	num_recs--;
273	data_start = hfs_bnode_read_u16(node, old_rec_off);
274	} else {
275	hfs_bnode_put(node);
276	hfs_bnode_get(new_node);
277	fd->bnode = new_node;
278	fd->record -= num_recs;
279	fd->keyoffset -= data_start - 14;
280	fd->entryoffset -= data_start - 14;
281	}
282	new_node->num_recs = node->num_recs - num_recs;
283	node->num_recs = num_recs;
284
285	new_rec_off = tree->node_size - 2;
286	new_off = 14;
287	size = data_start - new_off;
288	num_recs = new_node->num_recs;
289	data_end = data_start;
290	while (num_recs) {
291	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
292	old_rec_off -= 2;
293	new_rec_off -= 2;
294	data_end = hfs_bnode_read_u16(node, old_rec_off);
295	new_off = data_end - size;
296	num_recs--;
297	}
298	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
299	hfs_bnode_copy(new_node, 14, node, data_start, data_end - data_start);
300
301	/* update new bnode header */
302	node_desc.next = cpu_to_be32(new_node->next);
303	node_desc.prev = cpu_to_be32(new_node->prev);
304	node_desc.type = new_node->type;
305	node_desc.height = new_node->height;
306	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
307	node_desc.reserved = 0;
308	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
309
310	/* update previous bnode header */
311	node->next = new_node->this;
312	hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
313	node_desc.next = cpu_to_be32(node->next);
314	node_desc.num_recs = cpu_to_be16(node->num_recs);
315	hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));
316
317	/* update next bnode header */
318	if (new_node->next) {
319	struct hfs_bnode *next_node = hfs_bnode_find(tree, new_node->next);
320	next_node->prev = new_node->this;
321	hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
322	node_desc.prev = cpu_to_be32(next_node->prev);
323	hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
324	hfs_bnode_put(next_node);
325	} else if (node->this == tree->leaf_tail) {
326	/* if there is no next node, this might be the new tail */
327	tree->leaf_tail = new_node->this;
328	mark_inode_dirty(tree->inode);
329	}
330
331	hfs_bnode_dump(node);
332	hfs_bnode_dump(new_node);
333	hfs_bnode_put(node);
334
335	return new_node;
336	}
337
338	static int hfs_brec_update_parent(struct hfs_find_data *fd)
339	{
340	struct hfs_btree *tree;
341	struct hfs_bnode node, new_node, *parent;
342	int newkeylen, diff;
343	int rec, rec_off, end_rec_off;
344	int start_off, end_off;
345
346	tree = fd->tree;
347	node = fd->bnode;
348	new_node = NULL;
349	if (!node->parent)
350	return 0;
351
352	again:
353	parent = hfs_bnode_find(tree, node->parent);
354	if (IS_ERR(parent))
355	return PTR_ERR(parent);
356	__hfs_brec_find(parent, fd);
357	hfs_bnode_dump(parent);
358	rec = fd->record;
359
360	/* size difference between old and new key */
361	if (tree->attributes & HFS_TREE_VARIDXKEYS)
362	newkeylen = (hfs_bnode_read_u8(node, 14) \| 1) + 1;
363	else
364	fd->keylength = newkeylen = tree->max_key_len + 1;
365	dprint(DBG_BNODE_MOD, "update_rec: %d, %d, %d\n", rec, fd->keylength, newkeylen);
366
367	rec_off = tree->node_size - (rec + 2) * 2;
368	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
369	diff = newkeylen - fd->keylength;
370	if (!diff)
371	goto skip;
372	if (diff > 0) {
373	end_off = hfs_bnode_read_u16(parent, end_rec_off);
374	if (end_rec_off - end_off < diff) {
375
7cf3cc30	376	printk(KERN_DEBUG "hfs: splitting index node...\n");
1da177e4 LT	377	fd->bnode = parent;
	378	new_node = hfs_bnode_split(fd);
	379	if (IS_ERR(new_node))
	380	return PTR_ERR(new_node);
	381	parent = fd->bnode;
	382	rec = fd->record;
	383	rec_off = tree->node_size - (rec + 2) * 2;
	384	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
	385	}
	386	}
	387
	388	end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
	389	hfs_bnode_write_u16(parent, rec_off, start_off + diff);
	390	start_off -= 4; /* move previous cnid too */
	391
	392	while (rec_off > end_rec_off) {
	393	rec_off -= 2;
	394	end_off = hfs_bnode_read_u16(parent, rec_off);
	395	hfs_bnode_write_u16(parent, rec_off, end_off + diff);
	396	}
	397	hfs_bnode_move(parent, start_off + diff, start_off,
	398	end_off - start_off);
	399	skip:
	400	hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
	401	if (!(tree->attributes & HFS_TREE_VARIDXKEYS))
	402	hfs_bnode_write_u8(parent, fd->keyoffset, newkeylen - 1);
	403	hfs_bnode_dump(parent);
	404
	405	hfs_bnode_put(node);
	406	node = parent;
	407
	408	if (new_node) {
	409	__be32 cnid;
	410
	411	fd->bnode = hfs_bnode_find(tree, new_node->parent);
	412	/* create index key and entry */
	413	hfs_bnode_read_key(new_node, fd->search_key, 14);
	414	cnid = cpu_to_be32(new_node->this);
	415
	416	__hfs_brec_find(fd->bnode, fd);
	417	hfs_brec_insert(fd, &cnid, sizeof(cnid));
	418	hfs_bnode_put(fd->bnode);
	419	hfs_bnode_put(new_node);
	420
	421	if (!rec) {
	422	if (new_node == node)
	423	goto out;
	424	/* restore search_key */
	425	hfs_bnode_read_key(node, fd->search_key, 14);
	426	}
	427	}
	428
	429	if (!rec && node->parent)
	430	goto again;
	431	out:
	432	fd->bnode = node;
	433	return 0;
	434	}
	435
	436	static int hfs_btree_inc_height(struct hfs_btree *tree)
	437	{
	438	struct hfs_bnode node, new_node;
	439	struct hfs_bnode_desc node_desc;
	440	int key_size, rec;
441	__be32 cnid;
442
443	node = NULL;
444	if (tree->root) {
445	node = hfs_bnode_find(tree, tree->root);
446	if (IS_ERR(node))
447	return PTR_ERR(node);
448	}
449	new_node = hfs_bmap_alloc(tree);
450	if (IS_ERR(new_node)) {
451	hfs_bnode_put(node);
452	return PTR_ERR(new_node);
453	}
454
455	tree->root = new_node->this;
456	if (!tree->depth) {
457	tree->leaf_head = tree->leaf_tail = new_node->this;
458	new_node->type = HFS_NODE_LEAF;
459	new_node->num_recs = 0;
460	} else {
461	new_node->type = HFS_NODE_INDEX;
462	new_node->num_recs = 1;
463	}
464	new_node->parent = 0;
465	new_node->next = 0;
466	new_node->prev = 0;
467	new_node->height = ++tree->depth;
468
469	node_desc.next = cpu_to_be32(new_node->next);
470	node_desc.prev = cpu_to_be32(new_node->prev);
471	node_desc.type = new_node->type;
472	node_desc.height = new_node->height;
473	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
474	node_desc.reserved = 0;
475	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
476
477	rec = tree->node_size - 2;
478	hfs_bnode_write_u16(new_node, rec, 14);
479
480	if (node) {
481	/* insert old root idx into new root */
482	node->parent = tree->root;
483	if (node->type == HFS_NODE_LEAF \|\|
484	tree->attributes & HFS_TREE_VARIDXKEYS)
485	key_size = hfs_bnode_read_u8(node, 14) + 1;
486	else
487	key_size = tree->max_key_len + 1;
488	hfs_bnode_copy(new_node, 14, node, 14, key_size);
489
490	if (!(tree->attributes & HFS_TREE_VARIDXKEYS)) {
491	key_size = tree->max_key_len + 1;
492	hfs_bnode_write_u8(new_node, 14, tree->max_key_len);
493	}
494	key_size = (key_size + 1) & -2;
495	cnid = cpu_to_be32(node->this);
496	hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);
497
498	rec -= 2;
499	hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);
500
501	hfs_bnode_put(node);
502	}
503	hfs_bnode_put(new_node);
504	mark_inode_dirty(tree->inode);
505
506	return 0;
507	}