[net-next-2.6.git] / fs / hfsplus / brec.c

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

		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) {

			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);
	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 (flar@allandria.com)
	6	* (C) 2003 Ardis Technologies <roman@ardistech.com>
	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 {
	42	recoff = hfs_bnode_read_u16(node, node->tree->node_size - (rec + 1) * 2);
	43	if (!recoff)
	44	return 0;
13571a69 CH	45
	46	retval = hfs_bnode_read_u16(node, recoff) + 2;
	47	if (retval > node->tree->max_key_len + 2) {
	48	printk(KERN_ERR "hfs: keylen %d too large\n",
	49	retval);
	50	retval = 0;
9250f925	51	}
1da177e4 LT	52	}
	53	return retval;
	54	}
	55
	56	int hfs_brec_insert(struct hfs_find_data fd, void entry, int entry_len)
	57	{
	58	struct hfs_btree *tree;
	59	struct hfs_bnode node, new_node;
	60	int size, key_len, rec;
	61	int data_off, end_off;
	62	int idx_rec_off, data_rec_off, end_rec_off;
	63	__be32 cnid;
	64
	65	tree = fd->tree;
	66	if (!fd->bnode) {
	67	if (!tree->root)
	68	hfs_btree_inc_height(tree);
	69	fd->bnode = hfs_bnode_find(tree, tree->leaf_head);
	70	if (IS_ERR(fd->bnode))
	71	return PTR_ERR(fd->bnode);
	72	fd->record = -1;
	73	}
	74	new_node = NULL;
	75	key_len = be16_to_cpu(fd->search_key->key_len) + 2;
	76	again:
	77	/* new record idx and complete record size */
	78	rec = fd->record + 1;
	79	size = key_len + entry_len;
	80
	81	node = fd->bnode;
	82	hfs_bnode_dump(node);
	83	/* get last offset */
	84	end_rec_off = tree->node_size - (node->num_recs + 1) * 2;
	85	end_off = hfs_bnode_read_u16(node, end_rec_off);
	86	end_rec_off -= 2;
	87	dprint(DBG_BNODE_MOD, "insert_rec: %d, %d, %d, %d\n", rec, size, end_off, end_rec_off);
	88	if (size > end_rec_off - end_off) {
	89	if (new_node)
	90	panic("not enough room!\n");
	91	new_node = hfs_bnode_split(fd);
	92	if (IS_ERR(new_node))
	93	return PTR_ERR(new_node);
	94	goto again;
	95	}
	96	if (node->type == HFS_NODE_LEAF) {
	97	tree->leaf_count++;
	98	mark_inode_dirty(tree->inode);
	99	}
	100	node->num_recs++;
	101	/* write new last offset */
	102	hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
	103	hfs_bnode_write_u16(node, end_rec_off, end_off + size);
	104	data_off = end_off;
	105	data_rec_off = end_rec_off + 2;
	106	idx_rec_off = tree->node_size - (rec + 1) * 2;
	107	if (idx_rec_off == data_rec_off)
	108	goto skip;
	109	/* move all following entries */
	110	do {
	111	data_off = hfs_bnode_read_u16(node, data_rec_off + 2);
	112	hfs_bnode_write_u16(node, data_rec_off, data_off + size);
	113	data_rec_off += 2;
	114	} while (data_rec_off < idx_rec_off);
	115
116	/* move data away */
117	hfs_bnode_move(node, data_off + size, data_off,
118	end_off - data_off);
119
120	skip:
121	hfs_bnode_write(node, fd->search_key, data_off, key_len);
122	hfs_bnode_write(node, entry, data_off + key_len, entry_len);
123	hfs_bnode_dump(node);
124
125	if (new_node) {
126	/* update parent key if we inserted a key
127	* at the start of the first node
128	*/
129	if (!rec && new_node != node)
130	hfs_brec_update_parent(fd);
131
132	hfs_bnode_put(fd->bnode);
133	if (!new_node->parent) {
134	hfs_btree_inc_height(tree);
135	new_node->parent = tree->root;
136	}
137	fd->bnode = hfs_bnode_find(tree, new_node->parent);
138
139	/* create index data entry */
140	cnid = cpu_to_be32(new_node->this);
141	entry = &cnid;
142	entry_len = sizeof(cnid);
143
144	/* get index key */
145	hfs_bnode_read_key(new_node, fd->search_key, 14);
146	__hfs_brec_find(fd->bnode, fd);
147
148	hfs_bnode_put(new_node);
149	new_node = NULL;
150
151	if (tree->attributes & HFS_TREE_VARIDXKEYS)
152	key_len = be16_to_cpu(fd->search_key->key_len) + 2;
153	else {
154	fd->search_key->key_len = cpu_to_be16(tree->max_key_len);
155	key_len = tree->max_key_len + 2;
156	}
157	goto again;
158	}
159
160	if (!rec)
161	hfs_brec_update_parent(fd);
162
163	return 0;
164	}
165
166	int hfs_brec_remove(struct hfs_find_data *fd)
167	{
168	struct hfs_btree *tree;
169	struct hfs_bnode node, parent;
170	int end_off, rec_off, data_off, size;
171
172	tree = fd->tree;
173	node = fd->bnode;
174	again:
175	rec_off = tree->node_size - (fd->record + 2) * 2;
176	end_off = tree->node_size - (node->num_recs + 1) * 2;
177
178	if (node->type == HFS_NODE_LEAF) {
179	tree->leaf_count--;
180	mark_inode_dirty(tree->inode);
181	}
182	hfs_bnode_dump(node);
183	dprint(DBG_BNODE_MOD, "remove_rec: %d, %d\n", fd->record, fd->keylength + fd->entrylength);
184	if (!--node->num_recs) {
185	hfs_bnode_unlink(node);
186	if (!node->parent)
187	return 0;
188	parent = hfs_bnode_find(tree, node->parent);
189	if (IS_ERR(parent))
190	return PTR_ERR(parent);
191	hfs_bnode_put(node);
192	node = fd->bnode = parent;
193
194	__hfs_brec_find(node, fd);
195	goto again;
196	}
197	hfs_bnode_write_u16(node, offsetof(struct hfs_bnode_desc, num_recs), node->num_recs);
198
199	if (rec_off == end_off)
200	goto skip;
201	size = fd->keylength + fd->entrylength;
202
203	do {
204	data_off = hfs_bnode_read_u16(node, rec_off);
205	hfs_bnode_write_u16(node, rec_off + 2, data_off - size);
206	rec_off -= 2;
207	} while (rec_off >= end_off);
208
209	/* fill hole */
210	hfs_bnode_move(node, fd->keyoffset, fd->keyoffset + size,
211	data_off - fd->keyoffset - size);
212	skip:
213	hfs_bnode_dump(node);
214	if (!fd->record)
215	hfs_brec_update_parent(fd);
216	return 0;
217	}
218
219	static struct hfs_bnode hfs_bnode_split(struct hfs_find_data fd)
220	{
221	struct hfs_btree *tree;
b6b41424	222	struct hfs_bnode node, new_node, *next_node;
1da177e4 LT	223	struct hfs_bnode_desc node_desc;
	224	int num_recs, new_rec_off, new_off, old_rec_off;
	225	int data_start, data_end, size;
	226
	227	tree = fd->tree;
	228	node = fd->bnode;
	229	new_node = hfs_bmap_alloc(tree);
	230	if (IS_ERR(new_node))
	231	return new_node;
	232	hfs_bnode_get(node);
	233	dprint(DBG_BNODE_MOD, "split_nodes: %d - %d - %d\n",
	234	node->this, new_node->this, node->next);
	235	new_node->next = node->next;
	236	new_node->prev = node->this;
	237	new_node->parent = node->parent;
	238	new_node->type = node->type;
	239	new_node->height = node->height;
	240
b6b41424 AV	241	if (node->next)
	242	next_node = hfs_bnode_find(tree, node->next);
	243	else
	244	next_node = NULL;
	245
	246	if (IS_ERR(next_node)) {
	247	hfs_bnode_put(node);
	248	hfs_bnode_put(new_node);
	249	return next_node;
	250	}
	251
1da177e4 LT	252	size = tree->node_size / 2 - node->num_recs * 2 - 14;
	253	old_rec_off = tree->node_size - 4;
	254	num_recs = 1;
	255	for (;;) {
	256	data_start = hfs_bnode_read_u16(node, old_rec_off);
	257	if (data_start > size)
	258	break;
	259	old_rec_off -= 2;
	260	if (++num_recs < node->num_recs)
	261	continue;
	262	/* panic? */
	263	hfs_bnode_put(node);
	264	hfs_bnode_put(new_node);
b6b41424 AV	265	if (next_node)
b6b41424 AV	266	hfs_bnode_put(next_node);
1da177e4 LT	267	return ERR_PTR(-ENOSPC);
	268	}
	269
	270	if (fd->record + 1 < num_recs) {
	271	/* new record is in the lower half,
	272	* so leave some more space there
	273	*/
	274	old_rec_off += 2;
	275	num_recs--;
	276	data_start = hfs_bnode_read_u16(node, old_rec_off);
	277	} else {
	278	hfs_bnode_put(node);
	279	hfs_bnode_get(new_node);
	280	fd->bnode = new_node;
	281	fd->record -= num_recs;
	282	fd->keyoffset -= data_start - 14;
	283	fd->entryoffset -= data_start - 14;
	284	}
	285	new_node->num_recs = node->num_recs - num_recs;
	286	node->num_recs = num_recs;
	287
	288	new_rec_off = tree->node_size - 2;
	289	new_off = 14;
	290	size = data_start - new_off;
	291	num_recs = new_node->num_recs;
	292	data_end = data_start;
	293	while (num_recs) {
	294	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
	295	old_rec_off -= 2;
	296	new_rec_off -= 2;
	297	data_end = hfs_bnode_read_u16(node, old_rec_off);
	298	new_off = data_end - size;
	299	num_recs--;
	300	}
	301	hfs_bnode_write_u16(new_node, new_rec_off, new_off);
	302	hfs_bnode_copy(new_node, 14, node, data_start, data_end - data_start);
	303
	304	/* update new bnode header */
	305	node_desc.next = cpu_to_be32(new_node->next);
	306	node_desc.prev = cpu_to_be32(new_node->prev);
	307	node_desc.type = new_node->type;
	308	node_desc.height = new_node->height;
	309	node_desc.num_recs = cpu_to_be16(new_node->num_recs);
	310	node_desc.reserved = 0;
	311	hfs_bnode_write(new_node, &node_desc, 0, sizeof(node_desc));
	312
	313	/* update previous bnode header */
	314	node->next = new_node->this;
	315	hfs_bnode_read(node, &node_desc, 0, sizeof(node_desc));
	316	node_desc.next = cpu_to_be32(node->next);
	317	node_desc.num_recs = cpu_to_be16(node->num_recs);
	318	hfs_bnode_write(node, &node_desc, 0, sizeof(node_desc));
	319
	320	/* update next bnode header */
b6b41424	321	if (next_node) {
1da177e4 LT	322	next_node->prev = new_node->this;
	323	hfs_bnode_read(next_node, &node_desc, 0, sizeof(node_desc));
	324	node_desc.prev = cpu_to_be32(next_node->prev);
	325	hfs_bnode_write(next_node, &node_desc, 0, sizeof(node_desc));
	326	hfs_bnode_put(next_node);
	327	} else if (node->this == tree->leaf_tail) {
	328	/* if there is no next node, this might be the new tail */
	329	tree->leaf_tail = new_node->this;
	330	mark_inode_dirty(tree->inode);
	331	}
	332
	333	hfs_bnode_dump(node);
	334	hfs_bnode_dump(new_node);
	335	hfs_bnode_put(node);
	336
	337	return new_node;
	338	}
	339
	340	static int hfs_brec_update_parent(struct hfs_find_data *fd)
	341	{
	342	struct hfs_btree *tree;
	343	struct hfs_bnode node, new_node, *parent;
	344	int newkeylen, diff;
	345	int rec, rec_off, end_rec_off;
	346	int start_off, end_off;
	347
	348	tree = fd->tree;
	349	node = fd->bnode;
	350	new_node = NULL;
	351	if (!node->parent)
	352	return 0;
	353
	354	again:
	355	parent = hfs_bnode_find(tree, node->parent);
	356	if (IS_ERR(parent))
	357	return PTR_ERR(parent);
	358	__hfs_brec_find(parent, fd);
	359	hfs_bnode_dump(parent);
	360	rec = fd->record;
	361
	362	/* size difference between old and new key */
	363	if (tree->attributes & HFS_TREE_VARIDXKEYS)
	364	newkeylen = hfs_bnode_read_u16(node, 14) + 2;
	365	else
	366	fd->keylength = newkeylen = tree->max_key_len + 2;
	367	dprint(DBG_BNODE_MOD, "update_rec: %d, %d, %d\n", rec, fd->keylength, newkeylen);
	368
	369	rec_off = tree->node_size - (rec + 2) * 2;
	370	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
	371	diff = newkeylen - fd->keylength;
	372	if (!diff)
	373	goto skip;
	374	if (diff > 0) {
	375	end_off = hfs_bnode_read_u16(parent, end_rec_off);
	376	if (end_rec_off - end_off < diff) {
	377
634725a9	378	printk(KERN_DEBUG "hfs: splitting index node...\n");
1da177e4 LT	379	fd->bnode = parent;
	380	new_node = hfs_bnode_split(fd);
	381	if (IS_ERR(new_node))
	382	return PTR_ERR(new_node);
	383	parent = fd->bnode;
	384	rec = fd->record;
	385	rec_off = tree->node_size - (rec + 2) * 2;
	386	end_rec_off = tree->node_size - (parent->num_recs + 1) * 2;
	387	}
	388	}
	389
	390	end_off = start_off = hfs_bnode_read_u16(parent, rec_off);
	391	hfs_bnode_write_u16(parent, rec_off, start_off + diff);
	392	start_off -= 4; /* move previous cnid too */
	393
	394	while (rec_off > end_rec_off) {
	395	rec_off -= 2;
	396	end_off = hfs_bnode_read_u16(parent, rec_off);
	397	hfs_bnode_write_u16(parent, rec_off, end_off + diff);
	398	}
	399	hfs_bnode_move(parent, start_off + diff, start_off,
	400	end_off - start_off);
	401	skip:
	402	hfs_bnode_copy(parent, fd->keyoffset, node, 14, newkeylen);
	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_u16(node, 14) + 2;
486	else
487	key_size = tree->max_key_len + 2;
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 + 2;
492	hfs_bnode_write_u16(new_node, 14, tree->max_key_len);
493	}
494	cnid = cpu_to_be32(node->this);
495	hfs_bnode_write(new_node, &cnid, 14 + key_size, 4);
496
497	rec -= 2;
498	hfs_bnode_write_u16(new_node, rec, 14 + key_size + 4);
499
500	hfs_bnode_put(node);
501	}
502	hfs_bnode_put(new_node);
503	mark_inode_dirty(tree->inode);
504
505	return 0;
506	}