From: Chris Mason <chris.mason@oracle.com>
Date: Fri, 26 Jan 2007 20:51:26 +0000 (-0500)
Subject: Btrfs: Initial checkin, basic working tree code
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=be0e5c097fc206b863ce9fe6b3cfd6974b0110f4;p=openwrt%2Fstaging%2Fblogic.git

Btrfs: Initial checkin, basic working tree code

Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

be0e5c097fc206b863ce9fe6b3cfd6974b0110f4
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
new file mode 100644
index 000000000000..893fd56960a0
--- /dev/null
+++ b/fs/btrfs/ctree.c
@@ -0,0 +1,810 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "kerncompat.h"
+
+#define BLOCKSIZE 4096
+
+struct key {
+	u64 objectid;
+	u32 flags;
+	u64 offset;
+} __attribute__ ((__packed__));
+
+struct header {
+	u64 fsid[2]; /* FS specific uuid */
+	u64 blocknum;
+	u64 parentid;
+	u32 csum;
+	u32 ham;
+	u16 nritems;
+	u16 flags;
+} __attribute__ ((__packed__));
+
+#define NODEPTRS_PER_BLOCK ((BLOCKSIZE - sizeof(struct header)) / \
+			    (sizeof(struct key) + sizeof(u64)))
+
+#define LEVEL_BITS 3
+#define MAX_LEVEL (1 << LEVEL_BITS)
+#define node_level(f) ((f) & (MAX_LEVEL-1))
+#define is_leaf(f) (node_level(f) == 0)
+
+struct ctree_root {
+	struct node *node;
+};
+
+struct item {
+	struct key key;
+	u16 offset;
+	u16 size;
+} __attribute__ ((__packed__));
+
+#define LEAF_DATA_SIZE (BLOCKSIZE - sizeof(struct header))
+struct leaf {
+	struct header header;
+	union {
+		struct item items[LEAF_DATA_SIZE/sizeof(struct item)];
+		u8 data[BLOCKSIZE-sizeof(struct header)];
+	};
+} __attribute__ ((__packed__));
+
+struct node {
+	struct header header;
+	struct key keys[NODEPTRS_PER_BLOCK];
+	u64 blockptrs[NODEPTRS_PER_BLOCK];
+} __attribute__ ((__packed__));
+
+struct ctree_path {
+	struct node *nodes[MAX_LEVEL];
+	int slots[MAX_LEVEL];
+};
+
+static inline void init_path(struct ctree_path *p)
+{
+	memset(p, 0, sizeof(*p));
+}
+
+static inline unsigned int leaf_data_end(struct leaf *leaf)
+{
+	unsigned int nr = leaf->header.nritems;
+	if (nr == 0)
+		return ARRAY_SIZE(leaf->data);
+	return leaf->items[nr-1].offset;
+}
+
+static inline int leaf_free_space(struct leaf *leaf)
+{
+	int data_end = leaf_data_end(leaf);
+	int nritems = leaf->header.nritems;
+	char *items_end = (char *)(leaf->items + nritems + 1);
+	return (char *)(leaf->data + data_end) - (char *)items_end;
+}
+
+int comp_keys(struct key *k1, struct key *k2)
+{
+	if (k1->objectid > k2->objectid)
+		return 1;
+	if (k1->objectid < k2->objectid)
+		return -1;
+	if (k1->flags > k2->flags)
+		return 1;
+	if (k1->flags < k2->flags)
+		return -1;
+	if (k1->offset > k2->offset)
+		return 1;
+	if (k1->offset < k2->offset)
+		return -1;
+	return 0;
+}
+int generic_bin_search(char *p, int item_size, struct key *key,
+		       int max, int *slot)
+{
+	int low = 0;
+	int high = max;
+	int mid;
+	int ret;
+	struct key *tmp;
+
+	while(low < high) {
+		mid = (low + high) / 2;
+		tmp = (struct key *)(p + mid * item_size);
+		ret = comp_keys(tmp, key);
+
+		if (ret < 0)
+			low = mid + 1;
+		else if (ret > 0)
+			high = mid;
+		else {
+			*slot = mid;
+			return 0;
+		}
+	}
+	*slot = low;
+	return 1;
+}
+
+int bin_search(struct node *c, struct key *key, int *slot)
+{
+	if (is_leaf(c->header.flags)) {
+		struct leaf *l = (struct leaf *)c;
+		return generic_bin_search((void *)l->items, sizeof(struct item),
+					  key, c->header.nritems, slot);
+	} else {
+		return generic_bin_search((void *)c->keys, sizeof(struct key),
+					  key, c->header.nritems, slot);
+	}
+	return -1;
+}
+
+void *read_block(u64 blocknum)
+{
+	return (void *)blocknum;
+}
+
+int search_slot(struct ctree_root *root, struct key *key, struct ctree_path *p)
+{
+	struct node *c = root->node;
+	int slot;
+	int ret;
+	int level;
+	while (c) {
+		level = node_level(c->header.flags);
+		p->nodes[level] = c;
+		ret = bin_search(c, key, &slot);
+		if (!is_leaf(c->header.flags)) {
+			if (ret && slot > 0)
+				slot -= 1;
+			p->slots[level] = slot;
+			c = read_block(c->blockptrs[slot]);
+			continue;
+		} else {
+			p->slots[level] = slot;
+			return ret;
+		}
+	}
+	return -1;
+}
+
+static void fixup_low_keys(struct ctree_path *path, struct key *key,
+			     int level)
+{
+	int i;
+	/* adjust the pointers going up the tree */
+	for (i = level; i < MAX_LEVEL; i++) {
+		struct node *t = path->nodes[i];
+		int tslot = path->slots[i];
+		if (!t)
+			break;
+		memcpy(t->keys + tslot, key, sizeof(*key));
+		if (tslot != 0)
+			break;
+	}
+}
+
+int __insert_ptr(struct ctree_root *root,
+		struct ctree_path *path, struct key *key,
+		u64 blocknr, int slot, int level)
+{
+	struct node *c;
+	struct node *lower;
+	struct key *lower_key;
+	int nritems;
+	/* need a new root */
+	if (!path->nodes[level]) {
+		c = malloc(sizeof(struct node));
+		memset(c, 0, sizeof(c));
+		c->header.nritems = 2;
+		c->header.flags = node_level(level);
+		lower = path->nodes[level-1];
+		if (is_leaf(lower->header.flags))
+			lower_key = &((struct leaf *)lower)->items[0].key;
+		else
+			lower_key = lower->keys;
+		memcpy(c->keys, lower_key, sizeof(struct key));
+		memcpy(c->keys + 1, key, sizeof(struct key));
+		c->blockptrs[0] = (u64)lower;
+		c->blockptrs[1] = blocknr;
+		root->node = c;
+		path->nodes[level] = c;
+		path->slots[level] = 0;
+		if (c->keys[1].objectid == 0)
+			BUG();
+		return 0;
+	}
+	lower = path->nodes[level];
+	nritems = lower->header.nritems;
+	if (slot > nritems)
+		BUG();
+	if (nritems == NODEPTRS_PER_BLOCK)
+		BUG();
+	if (slot != nritems) {
+		memmove(lower->keys + slot + 1, lower->keys + slot,
+			(nritems - slot) * sizeof(struct key));
+		memmove(lower->blockptrs + slot + 1, lower->blockptrs + slot,
+			(nritems - slot) * sizeof(u64));
+	}
+	memcpy(lower->keys + slot, key, sizeof(struct key));
+	lower->blockptrs[slot] = blocknr;
+	lower->header.nritems++;
+	if (lower->keys[1].objectid == 0)
+			BUG();
+	return 0;
+}
+
+int push_node_left(struct ctree_root *root, struct ctree_path *path, int level)
+{
+	int slot;
+	struct node *left;
+	struct node *right;
+	int push_items = 0;
+	int left_nritems;
+	int right_nritems;
+
+	if (level == MAX_LEVEL - 1 || path->nodes[level + 1] == 0)
+		return 1;
+	slot = path->slots[level + 1];
+	if (slot == 0)
+		return 1;
+
+	left = read_block(path->nodes[level + 1]->blockptrs[slot - 1]);
+	right = path->nodes[level];
+	left_nritems = left->header.nritems;
+	right_nritems = right->header.nritems;
+	push_items = NODEPTRS_PER_BLOCK - (left_nritems + 1);
+	if (push_items <= 0)
+		return 1;
+
+	if (right_nritems < push_items)
+		push_items = right_nritems;
+	memcpy(left->keys + left_nritems, right->keys,
+		push_items * sizeof(struct key));
+	memcpy(left->blockptrs + left_nritems, right->blockptrs,
+		push_items * sizeof(u64));
+	memmove(right->keys, right->keys + push_items,
+		(right_nritems - push_items) * sizeof(struct key));
+	memmove(right->blockptrs, right->blockptrs + push_items,
+		(right_nritems - push_items) * sizeof(u64));
+	right->header.nritems -= push_items;
+	left->header.nritems += push_items;
+
+	/* adjust the pointers going up the tree */
+	fixup_low_keys(path, right->keys, level + 1);
+
+	/* then fixup the leaf pointer in the path */
+	if (path->slots[level] < push_items) {
+		path->slots[level] += left_nritems;
+		path->nodes[level] = (struct node*)left;
+		path->slots[level + 1] -= 1;
+	} else {
+		path->slots[level] -= push_items;
+	}
+	return 0;
+}
+
+int push_node_right(struct ctree_root *root, struct ctree_path *path, int level)
+{
+	int slot;
+	struct node *dst;
+	struct node *src;
+	int push_items = 0;
+	int dst_nritems;
+	int src_nritems;
+
+	if (level == MAX_LEVEL - 1 || path->nodes[level + 1] == 0)
+		return 1;
+	slot = path->slots[level + 1];
+	if (slot == NODEPTRS_PER_BLOCK - 1)
+		return 1;
+
+	if (slot >= path->nodes[level + 1]->header.nritems -1)
+		return 1;
+
+	dst = read_block(path->nodes[level + 1]->blockptrs[slot + 1]);
+	src = path->nodes[level];
+	dst_nritems = dst->header.nritems;
+	src_nritems = src->header.nritems;
+	push_items = NODEPTRS_PER_BLOCK - (dst_nritems + 1);
+	if (push_items <= 0)
+		return 1;
+
+	if (src_nritems < push_items)
+		push_items = src_nritems;
+	memmove(dst->keys + push_items, dst->keys,
+		dst_nritems * sizeof(struct key));
+	memcpy(dst->keys, src->keys + src_nritems - push_items,
+		push_items * sizeof(struct key));
+
+	memmove(dst->blockptrs + push_items, dst->blockptrs,
+		dst_nritems * sizeof(u64));
+	memcpy(dst->blockptrs, src->blockptrs + src_nritems - push_items,
+		push_items * sizeof(u64));
+
+	src->header.nritems -= push_items;
+	dst->header.nritems += push_items;
+
+	/* adjust the pointers going up the tree */
+	memcpy(path->nodes[level + 1]->keys + path->slots[level + 1] + 1,
+		dst->keys, sizeof(struct key));
+	/* then fixup the leaf pointer in the path */
+	if (path->slots[level] >= src->header.nritems) {
+		path->slots[level] -= src->header.nritems;
+		path->nodes[level] = (struct node*)dst;
+		path->slots[level + 1] += 1;
+	}
+	return 0;
+}
+
+int insert_ptr(struct ctree_root *root,
+		struct ctree_path *path, struct key *key,
+		u64 blocknr, int level)
+{
+	struct node *c = path->nodes[level];
+	struct node *b;
+	struct node *bal[MAX_LEVEL];
+	int bal_level = level;
+	int mid;
+	int bal_start = -1;
+
+	memset(bal, 0, ARRAY_SIZE(bal));
+	while(c && c->header.nritems == NODEPTRS_PER_BLOCK) {
+		if (push_node_left(root, path,
+		   node_level(c->header.flags)) == 0)
+			break;
+		if (push_node_right(root, path,
+		   node_level(c->header.flags)) == 0)
+			break;
+		bal_start = bal_level;
+		if (bal_level == MAX_LEVEL - 1)
+			BUG();
+		b = malloc(sizeof(struct node));
+		b->header.flags = c->header.flags;
+		mid = (c->header.nritems + 1) / 2;
+		memcpy(b->keys, c->keys + mid,
+			(c->header.nritems - mid) * sizeof(struct key));
+		memcpy(b->blockptrs, c->blockptrs + mid,
+			(c->header.nritems - mid) * sizeof(u64));
+		b->header.nritems = c->header.nritems - mid;
+		c->header.nritems = mid;
+		bal[bal_level] = b;
+		if (bal_level == MAX_LEVEL - 1)
+			break;
+		bal_level += 1;
+		c = path->nodes[bal_level];
+	}
+	while(bal_start > 0) {
+		b = bal[bal_start];
+		c = path->nodes[bal_start];
+		__insert_ptr(root, path, b->keys, (u64)b,
+				path->slots[bal_start + 1] + 1, bal_start + 1);
+		if (path->slots[bal_start] >= c->header.nritems) {
+			path->slots[bal_start] -= c->header.nritems;
+			path->nodes[bal_start] = b;
+			path->slots[bal_start + 1] += 1;
+		}
+		bal_start--;
+		if (!bal[bal_start])
+			break;
+	}
+	return __insert_ptr(root, path, key, blocknr, path->slots[level] + 1,
+			    level);
+}
+
+int leaf_space_used(struct leaf *l, int start, int nr)
+{
+	int data_len;
+	int end = start + nr - 1;
+
+	if (!nr)
+		return 0;
+	data_len = l->items[start].offset + l->items[start].size;
+	data_len = data_len - l->items[end].offset;
+	data_len += sizeof(struct item) * nr;
+	return data_len;
+}
+
+int push_leaf_left(struct ctree_root *root, struct ctree_path *path,
+		   int data_size)
+{
+	struct leaf *right = (struct leaf *)path->nodes[0];
+	struct leaf *left;
+	int slot;
+	int i;
+	int free_space;
+	int push_space = 0;
+	int push_items = 0;
+	struct item *item;
+	int old_left_nritems;
+
+	slot = path->slots[1];
+	if (slot == 0) {
+		return 1;
+	}
+	if (!path->nodes[1]) {
+		return 1;
+	}
+	left = read_block(path->nodes[1]->blockptrs[slot - 1]);
+	free_space = leaf_free_space(left);
+	if (free_space < data_size + sizeof(struct item)) {
+		return 1;
+	}
+	for (i = 0; i < right->header.nritems; i++) {
+		item = right->items + i;
+		if (path->slots[0] == i)
+			push_space += data_size + sizeof(*item);
+		if (item->size + sizeof(*item) + push_space > free_space)
+			break;
+		push_items++;
+		push_space += item->size + sizeof(*item);
+	}
+	if (push_items == 0) {
+		return 1;
+	}
+	/* push data from right to left */
+	memcpy(left->items + left->header.nritems,
+		right->items, push_items * sizeof(struct item));
+	push_space = LEAF_DATA_SIZE - right->items[push_items -1].offset;
+	memcpy(left->data + leaf_data_end(left) - push_space,
+		right->data + right->items[push_items - 1].offset,
+		push_space);
+	old_left_nritems = left->header.nritems;
+	for(i = old_left_nritems; i < old_left_nritems + push_items; i++) {
+		left->items[i].offset -= LEAF_DATA_SIZE -
+			left->items[old_left_nritems -1].offset;
+	}
+	left->header.nritems += push_items;
+
+	/* fixup right node */
+	push_space = right->items[push_items-1].offset - leaf_data_end(right);
+	memmove(right->data + LEAF_DATA_SIZE - push_space, right->data +
+		leaf_data_end(right), push_space);
+	memmove(right->items, right->items + push_items,
+		(right->header.nritems - push_items) * sizeof(struct item));
+	right->header.nritems -= push_items;
+	push_space = LEAF_DATA_SIZE;
+	for (i = 0; i < right->header.nritems; i++) {
+		right->items[i].offset = push_space - right->items[i].size;
+		push_space = right->items[i].offset;
+	}
+	fixup_low_keys(path, &right->items[0].key, 1);
+
+	/* then fixup the leaf pointer in the path */
+	if (path->slots[0] < push_items) {
+		path->slots[0] += old_left_nritems;
+		path->nodes[0] = (struct node*)left;
+		path->slots[1] -= 1;
+	} else {
+		path->slots[0] -= push_items;
+	}
+	return 0;
+}
+
+int split_leaf(struct ctree_root *root, struct ctree_path *path, int data_size)
+{
+	struct leaf *l = (struct leaf *)path->nodes[0];
+	int nritems = l->header.nritems;
+	int mid = (nritems + 1)/ 2;
+	int slot = path->slots[0];
+	struct leaf *right;
+	int space_needed = data_size + sizeof(struct item);
+	int data_copy_size;
+	int rt_data_off;
+	int i;
+	int ret;
+
+	if (push_leaf_left(root, path, data_size) == 0) {
+		return 0;
+	}
+	right = malloc(sizeof(struct leaf));
+	memset(right, 0, sizeof(*right));
+	if (mid <= slot) {
+		if (leaf_space_used(l, mid, nritems - mid) + space_needed >
+			LEAF_DATA_SIZE)
+			BUG();
+	} else {
+		if (leaf_space_used(l, 0, mid + 1) + space_needed >
+			LEAF_DATA_SIZE)
+			BUG();
+	}
+	right->header.nritems = nritems - mid;
+	data_copy_size = l->items[mid].offset + l->items[mid].size -
+			 leaf_data_end(l);
+	memcpy(right->items, l->items + mid,
+	       (nritems - mid) * sizeof(struct item));
+	memcpy(right->data + LEAF_DATA_SIZE - data_copy_size,
+	       l->data + leaf_data_end(l), data_copy_size);
+	rt_data_off = LEAF_DATA_SIZE -
+		     (l->items[mid].offset + l->items[mid].size);
+	for (i = 0; i < right->header.nritems; i++) {
+		right->items[i].offset += rt_data_off;
+	}
+	l->header.nritems = mid;
+	ret = insert_ptr(root, path, &right->items[0].key,
+			  (u64)right, 1);
+	if (mid <= slot) {
+		path->nodes[0] = (struct node *)right;
+		path->slots[0] -= mid;
+		path->slots[1] += 1;
+	}
+	return ret;
+}
+
+int insert_item(struct ctree_root *root, struct key *key,
+			  void *data, int data_size)
+{
+	int ret;
+	int slot;
+	struct leaf *leaf;
+	unsigned int nritems;
+	unsigned int data_end;
+	struct ctree_path path;
+
+	init_path(&path);
+	ret = search_slot(root, key, &path);
+	if (ret == 0)
+		return -EEXIST;
+
+	leaf = (struct leaf *)path.nodes[0];
+	if (leaf_free_space(leaf) <  sizeof(struct item) + data_size)
+		split_leaf(root, &path, data_size);
+	leaf = (struct leaf *)path.nodes[0];
+	nritems = leaf->header.nritems;
+	data_end = leaf_data_end(leaf);
+	if (leaf_free_space(leaf) <  sizeof(struct item) + data_size)
+		BUG();
+
+	slot = path.slots[0];
+	if (slot == 0)
+		fixup_low_keys(&path, key, 1);
+	if (slot != nritems) {
+		int i;
+		unsigned int old_data = leaf->items[slot].offset +
+					leaf->items[slot].size;
+
+		/*
+		 * item0..itemN ... dataN.offset..dataN.size .. data0.size
+		 */
+		/* first correct the data pointers */
+		for (i = slot; i < nritems; i++)
+			leaf->items[i].offset -= data_size;
+
+		/* shift the items */
+		memmove(leaf->items + slot + 1, leaf->items + slot,
+		        (nritems - slot) * sizeof(struct item));
+
+		/* shift the data */
+		memmove(leaf->data + data_end - data_size, leaf->data +
+		        data_end, old_data - data_end);
+		data_end = old_data;
+	}
+	memcpy(&leaf->items[slot].key, key, sizeof(struct key));
+	leaf->items[slot].offset = data_end - data_size;
+	leaf->items[slot].size = data_size;
+	memcpy(leaf->data + data_end - data_size, data, data_size);
+	leaf->header.nritems += 1;
+	if (leaf_free_space(leaf) < 0)
+		BUG();
+	return 0;
+}
+
+int del_ptr(struct ctree_root *root, struct ctree_path *path, int level)
+{
+	int slot;
+	struct node *node;
+	int nritems;
+
+	while(1) {
+		node = path->nodes[level];
+		if (!node)
+			break;
+		slot = path->slots[level];
+		nritems = node->header.nritems;
+
+		if (slot != nritems -1) {
+			memmove(node->keys + slot, node->keys + slot + 1,
+				sizeof(struct key) * (nritems - slot - 1));
+			memmove(node->blockptrs + slot,
+				node->blockptrs + slot + 1,
+				sizeof(u64) * (nritems - slot - 1));
+		}
+		node->header.nritems--;
+		if (node->header.nritems != 0) {
+			int tslot;
+			if (slot == 0)
+				fixup_low_keys(path, node->keys, level + 1);
+			tslot = path->slots[level+1];
+			push_node_left(root, path, level);
+			if (node->header.nritems) {
+				push_node_right(root, path, level);
+			}
+			path->slots[level+1] = tslot;
+			if (node->header.nritems)
+				break;
+		}
+		if (node == root->node) {
+			printf("root is now null!\n");
+			root->node = NULL;
+			break;
+		}
+		level++;
+		if (!path->nodes[level])
+			BUG();
+		free(node);
+	}
+	return 0;
+}
+
+int del_item(struct ctree_root *root, struct key *key)
+{
+	int ret;
+	int slot;
+	struct leaf *leaf;
+	struct ctree_path path;
+	int doff;
+	int dsize;
+
+	init_path(&path);
+	ret = search_slot(root, key, &path);
+	if (ret != 0)
+		return -1;
+
+	leaf = (struct leaf *)path.nodes[0];
+	slot = path.slots[0];
+	doff = leaf->items[slot].offset;
+	dsize = leaf->items[slot].size;
+
+	if (slot != leaf->header.nritems - 1) {
+		int i;
+		int data_end = leaf_data_end(leaf);
+		memmove(leaf->data + data_end + dsize,
+			leaf->data + data_end,
+			doff - data_end);
+		for (i = slot + 1; i < leaf->header.nritems; i++)
+			leaf->items[i].offset += dsize;
+		memmove(leaf->items + slot, leaf->items + slot + 1,
+			sizeof(struct item) *
+			(leaf->header.nritems - slot - 1));
+	}
+	leaf->header.nritems -= 1;
+	if (leaf->header.nritems == 0) {
+		free(leaf);
+		del_ptr(root, &path, 1);
+	} else {
+		if (slot == 0)
+			fixup_low_keys(&path, &leaf->items[0].key, 1);
+		if (leaf_space_used(leaf, 0, leaf->header.nritems) <
+		    LEAF_DATA_SIZE / 4) {
+			/* push_leaf_left fixes the path.
+			 * make sure the path still points to our leaf
+			 * for possible call to del_ptr below
+			 */
+			slot = path.slots[1];
+			push_leaf_left(root, &path, 1);
+			path.slots[1] = slot;
+			if (leaf->header.nritems == 0) {
+				free(leaf);
+				del_ptr(root, &path, 1);
+			}
+		}
+	}
+	return 0;
+}
+
+void print_leaf(struct leaf *l)
+{
+	int i;
+	int nr = l->header.nritems;
+	struct item *item;
+	printf("leaf %p total ptrs %d free space %d\n", l, nr,
+	       leaf_free_space(l));
+	fflush(stdout);
+	for (i = 0 ; i < nr ; i++) {
+		item = l->items + i;
+		printf("\titem %d key (%lu %u %lu) itemoff %d itemsize %d\n",
+			i,
+			item->key.objectid, item->key.flags, item->key.offset,
+			item->offset, item->size);
+		fflush(stdout);
+		printf("\t\titem data %.*s\n", item->size, l->data+item->offset);
+		fflush(stdout);
+	}
+}
+void print_tree(struct node *c)
+{
+	int i;
+	int nr;
+
+	if (!c)
+		return;
+	nr = c->header.nritems;
+	if (is_leaf(c->header.flags)) {
+		print_leaf((struct leaf *)c);
+		return;
+	}
+	printf("node %p level %d total ptrs %d free spc %lu\n", c,
+	        node_level(c->header.flags), c->header.nritems,
+		NODEPTRS_PER_BLOCK - c->header.nritems);
+	fflush(stdout);
+	for (i = 0; i < nr; i++) {
+		printf("\tkey %d (%lu %u %lu) block %lx\n",
+		       i,
+		       c->keys[i].objectid, c->keys[i].flags, c->keys[i].offset,
+		       c->blockptrs[i]);
+		fflush(stdout);
+	}
+	for (i = 0; i < nr; i++) {
+		struct node *next = read_block(c->blockptrs[i]);
+		if (is_leaf(next->header.flags) &&
+		    node_level(c->header.flags) != 1)
+			BUG();
+		if (node_level(next->header.flags) !=
+			node_level(c->header.flags) - 1)
+			BUG();
+		print_tree(next);
+	}
+
+}
+
+/* for testing only */
+int next_key(int i, int max_key) {
+	return rand() % max_key;
+	// return i;
+}
+
+int main() {
+	struct leaf *first_node = malloc(sizeof(struct leaf));
+	struct ctree_root root;
+	struct key ins;
+	char *buf;
+	int i;
+	int num;
+	int ret;
+	int run_size = 10000000;
+	int max_key = 100000000;
+	int tree_size = 0;
+	struct ctree_path path;
+
+
+	srand(55);
+	root.node = (struct node *)first_node;
+	memset(first_node, 0, sizeof(*first_node));
+	for (i = 0; i < run_size; i++) {
+		buf = malloc(64);
+		num = next_key(i, max_key);
+		// num = i;
+		sprintf(buf, "string-%d", num);
+		// printf("insert %d\n", num);
+		ins.objectid = num;
+		ins.offset = 0;
+		ins.flags = 0;
+		ret = insert_item(&root, &ins, buf, strlen(buf));
+		if (!ret)
+			tree_size++;
+	}
+	srand(55);
+	for (i = 0; i < run_size; i++) {
+		num = next_key(i, max_key);
+		ins.objectid = num;
+		ins.offset = 0;
+		ins.flags = 0;
+		init_path(&path);
+		ret = search_slot(&root, &ins, &path);
+		if (ret) {
+			print_tree(root.node);
+			printf("unable to find %d\n", num);
+			exit(1);
+		}
+	}
+	printf("node %p level %d total ptrs %d free spc %lu\n", root.node,
+	        node_level(root.node->header.flags), root.node->header.nritems,
+		NODEPTRS_PER_BLOCK - root.node->header.nritems);
+	// print_tree(root.node);
+	printf("all searches good\n");
+	i = 0;
+	srand(55);
+	for (i = 0; i < run_size; i++) {
+		num = next_key(i, max_key);
+		ins.objectid = num;
+		del_item(&root, &ins);
+	}
+	print_tree(root.node);
+	return 0;
+}