Btrfs: Go back to kmaps instead of page_address in extent_buffers
[linux-block.git] / fs / btrfs / ctree.c
index 3c5f4c2dd525d36667d9360b96bffce6004b6d8f..9427b79c5d796ff7a8cafe2b75577a5ddc609d27 100644 (file)
-#include <stdio.h>
-#include <stdlib.h>
-#include "kerncompat.h"
-#include "radix-tree.h"
+/*
+ * Copyright (C) 2007 Oracle.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/highmem.h>
 #include "ctree.h"
 #include "disk-io.h"
+#include "transaction.h"
 #include "print-tree.h"
 
-static int split_node(struct ctree_root *root, struct ctree_path *path,
-                     int level);
-static int split_leaf(struct ctree_root *root, struct ctree_path *path,
-                     int data_size);
-static int push_node_left(struct ctree_root *root, struct tree_buffer *dst,
-                         struct tree_buffer *src);
-static int balance_node_right(struct ctree_root *root,
-                             struct tree_buffer *dst_buf,
-                             struct tree_buffer *src_buf);
-static int del_ptr(struct ctree_root *root, struct ctree_path *path, int level,
-                  int slot);
-
-inline void init_path(struct ctree_path *p)
+static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_path *path, int level);
+static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_key *ins_key,
+                     struct btrfs_path *path, int data_size);
+static int push_node_left(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root, struct extent_buffer *dst,
+                         struct extent_buffer *src);
+static int balance_node_right(struct btrfs_trans_handle *trans,
+                             struct btrfs_root *root,
+                             struct extent_buffer *dst_buf,
+                             struct extent_buffer *src_buf);
+static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+                  struct btrfs_path *path, int level, int slot);
+
+inline void btrfs_init_path(struct btrfs_path *p)
 {
        memset(p, 0, sizeof(*p));
 }
 
-void release_path(struct ctree_root *root, struct ctree_path *p)
+struct btrfs_path *btrfs_alloc_path(void)
+{
+       struct btrfs_path *path;
+       path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS);
+       if (path) {
+               btrfs_init_path(path);
+               path->reada = 1;
+       }
+       return path;
+}
+
+void btrfs_free_path(struct btrfs_path *p)
+{
+       btrfs_release_path(NULL, p);
+       kmem_cache_free(btrfs_path_cachep, p);
+}
+
+void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p)
 {
        int i;
-       for (i = 0; i < MAX_LEVEL; i++) {
+       for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
                if (!p->nodes[i])
                        break;
-               tree_block_release(root, p->nodes[i]);
+               free_extent_buffer(p->nodes[i]);
        }
        memset(p, 0, sizeof(*p));
 }
 
+static int __btrfs_cow_block(struct btrfs_trans_handle *trans,
+                            struct btrfs_root *root,
+                            struct extent_buffer *buf,
+                            struct extent_buffer *parent, int parent_slot,
+                            struct extent_buffer **cow_ret,
+                            u64 search_start, u64 empty_size)
+{
+       struct extent_buffer *cow;
+       int ret = 0;
+       int different_trans = 0;
+
+       WARN_ON(root->ref_cows && trans->transid != root->last_trans);
+
+       cow = btrfs_alloc_free_block(trans, root, search_start, empty_size);
+       if (IS_ERR(cow))
+               return PTR_ERR(cow);
+
+       if (buf->len != root->sectorsize || cow->len != root->sectorsize)
+               WARN_ON(1);
+
+       copy_extent_buffer(cow, buf, 0, 0, cow->len);
+       btrfs_set_header_blocknr(cow, extent_buffer_blocknr(cow));
+       btrfs_set_header_generation(cow, trans->transid);
+       btrfs_set_header_owner(cow, root->root_key.objectid);
+
+       WARN_ON(btrfs_header_generation(buf) > trans->transid);
+       if (btrfs_header_generation(buf) != trans->transid) {
+               different_trans = 1;
+               ret = btrfs_inc_ref(trans, root, buf);
+               if (ret)
+                       return ret;
+       } else {
+               clean_tree_block(trans, root, buf);
+       }
+
+       if (buf == root->node) {
+               root->node = cow;
+               extent_buffer_get(cow);
+               if (buf != root->commit_root) {
+                       btrfs_free_extent(trans, root,
+                                         extent_buffer_blocknr(buf), 1, 1);
+               }
+               free_extent_buffer(buf);
+       } else {
+               btrfs_set_node_blockptr(parent, parent_slot,
+                                       extent_buffer_blocknr(cow));
+               btrfs_mark_buffer_dirty(parent);
+               WARN_ON(btrfs_header_generation(parent) != trans->transid);
+               btrfs_free_extent(trans, root, extent_buffer_blocknr(buf),1,1);
+       }
+       free_extent_buffer(buf);
+       btrfs_mark_buffer_dirty(cow);
+       *cow_ret = cow;
+       return 0;
+}
+
+int btrfs_cow_block(struct btrfs_trans_handle *trans,
+                   struct btrfs_root *root, struct extent_buffer *buf,
+                   struct extent_buffer *parent, int parent_slot,
+                   struct extent_buffer **cow_ret)
+{
+       u64 search_start;
+       if (trans->transaction != root->fs_info->running_transaction) {
+               printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
+                      root->fs_info->running_transaction->transid);
+               WARN_ON(1);
+       }
+       if (trans->transid != root->fs_info->generation) {
+               printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
+                      root->fs_info->generation);
+               WARN_ON(1);
+       }
+       if (btrfs_header_generation(buf) == trans->transid) {
+               *cow_ret = buf;
+               return 0;
+       }
+
+       search_start = extent_buffer_blocknr(buf) & ~((u64)65535);
+       return __btrfs_cow_block(trans, root, buf, parent,
+                                parent_slot, cow_ret, search_start, 0);
+}
+
+static int close_blocks(u64 blocknr, u64 other)
+{
+       if (blocknr < other && other - blocknr < 8)
+               return 1;
+       if (blocknr > other && blocknr - other < 8)
+               return 1;
+       return 0;
+}
+
+#if 0
+static int should_defrag_leaf(struct extent_buffer *eb)
+{
+       return 0;
+       struct btrfs_leaf *leaf = btrfs_buffer_leaf(eb);
+       struct btrfs_disk_key *key;
+       u32 nritems;
+
+       if (buffer_defrag(bh))
+               return 1;
+
+       nritems = btrfs_header_nritems(&leaf->header);
+       if (nritems == 0)
+               return 0;
+
+       key = &leaf->items[0].key;
+       if (btrfs_disk_key_type(key) == BTRFS_DIR_ITEM_KEY)
+               return 1;
+
+       key = &leaf->items[nritems-1].key;
+       if (btrfs_disk_key_type(key) == BTRFS_DIR_ITEM_KEY)
+               return 1;
+       if (nritems > 4) {
+               key = &leaf->items[nritems/2].key;
+               if (btrfs_disk_key_type(key) == BTRFS_DIR_ITEM_KEY)
+                       return 1;
+       }
+       return 0;
+}
+#endif
+
+int btrfs_realloc_node(struct btrfs_trans_handle *trans,
+                      struct btrfs_root *root, struct extent_buffer *parent,
+                      int cache_only, u64 *last_ret)
+{
+       return 0;
+#if 0
+       struct btrfs_node *parent_node;
+       struct extent_buffer *cur_eb;
+       struct extent_buffer *tmp_eb;
+       u64 blocknr;
+       u64 search_start = *last_ret;
+       u64 last_block = 0;
+       u64 other;
+       u32 parent_nritems;
+       int start_slot;
+       int end_slot;
+       int i;
+       int err = 0;
+       int parent_level;
+
+       if (trans->transaction != root->fs_info->running_transaction) {
+               printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
+                      root->fs_info->running_transaction->transid);
+               WARN_ON(1);
+       }
+       if (trans->transid != root->fs_info->generation) {
+               printk(KERN_CRIT "trans %Lu running %Lu\n", trans->transid,
+                      root->fs_info->generation);
+               WARN_ON(1);
+       }
+       if (buffer_defrag_done(parent))
+               return 0;
+
+       parent_node = btrfs_buffer_node(parent);
+       parent_nritems = btrfs_header_nritems(&parent_node->header);
+       parent_level = btrfs_header_level(&parent_node->header);
+
+       start_slot = 0;
+       end_slot = parent_nritems;
+
+       if (parent_nritems == 1)
+               return 0;
+
+       for (i = start_slot; i < end_slot; i++) {
+               int close = 1;
+               blocknr = btrfs_node_blockptr(parent_node, i);
+               if (last_block == 0)
+                       last_block = blocknr;
+               if (i > 0) {
+                       other = btrfs_node_blockptr(parent_node, i - 1);
+                       close = close_blocks(blocknr, other);
+               }
+               if (close && i < end_slot - 1) {
+                       other = btrfs_node_blockptr(parent_node, i + 1);
+                       close = close_blocks(blocknr, other);
+               }
+               if (close) {
+                       last_block = blocknr;
+                       continue;
+               }
+
+               cur_bh = btrfs_find_tree_block(root, blocknr);
+               if (!cur_bh || !buffer_uptodate(cur_bh) ||
+                   buffer_locked(cur_bh) ||
+                   (parent_level != 1 && !buffer_defrag(cur_bh)) ||
+                   (parent_level == 1 && !should_defrag_leaf(cur_bh))) {
+                       if (cache_only) {
+                               brelse(cur_bh);
+                               continue;
+                       }
+                       if (!cur_bh || !buffer_uptodate(cur_bh) ||
+                           buffer_locked(cur_bh)) {
+                               brelse(cur_bh);
+                               cur_bh = read_tree_block(root, blocknr);
+                       }
+               }
+               if (search_start == 0)
+                       search_start = last_block & ~((u64)65535);
+
+               err = __btrfs_cow_block(trans, root, cur_bh, parent, i,
+                                       &tmp_bh, search_start,
+                                       min(8, end_slot - i));
+               if (err) {
+                       brelse(cur_bh);
+                       break;
+               }
+               search_start = bh_blocknr(tmp_bh);
+               *last_ret = search_start;
+               if (parent_level == 1)
+                       clear_buffer_defrag(tmp_bh);
+               set_buffer_defrag_done(tmp_bh);
+               brelse(tmp_bh);
+       }
+       return err;
+#endif
+}
+
 /*
  * The leaf data grows from end-to-front in the node.
  * this returns the address of the start of the last item,
  * which is the stop of the leaf data stack
  */
-static inline unsigned int leaf_data_end(struct leaf *leaf)
+static inline unsigned int leaf_data_end(struct btrfs_root *root,
+                                        struct extent_buffer *leaf)
 {
-       unsigned int nr = leaf->header.nritems;
+       u32 nr = btrfs_header_nritems(leaf);
        if (nr == 0)
-               return sizeof(leaf->data);
-       return leaf->items[nr-1].offset;
-}
-
-/*
- * The space between the end of the leaf items and
- * the start of the leaf data.  IOW, how much room
- * the leaf has left for both items and data
- */
-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;
+               return BTRFS_LEAF_DATA_SIZE(root);
+       return btrfs_item_offset_nr(leaf, nr - 1);
 }
 
 /*
  * compare two keys in a memcmp fashion
  */
-int comp_keys(struct key *k1, struct key *k2)
+static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
 {
-       if (k1->objectid > k2->objectid)
+       struct btrfs_key k1;
+
+       btrfs_disk_key_to_cpu(&k1, disk);
+
+       if (k1.objectid > k2->objectid)
                return 1;
-       if (k1->objectid < k2->objectid)
+       if (k1.objectid < k2->objectid)
                return -1;
-       if (k1->flags > k2->flags)
+       if (k1.type > k2->type)
                return 1;
-       if (k1->flags < k2->flags)
+       if (k1.type < k2->type)
                return -1;
-       if (k1->offset > k2->offset)
+       if (k1.offset > k2->offset)
                return 1;
-       if (k1->offset < k2->offset)
+       if (k1.offset < k2->offset)
                return -1;
        return 0;
 }
 
-int check_node(struct ctree_path *path, int level)
+static int check_node(struct btrfs_root *root, struct btrfs_path *path,
+                     int level)
 {
-       int i;
-       struct node *parent = NULL;
-       struct node *node = &path->nodes[level]->node;
+       struct extent_buffer *parent = NULL;
+       struct extent_buffer *node = path->nodes[level];
+       struct btrfs_disk_key parent_key;
+       struct btrfs_disk_key node_key;
        int parent_slot;
+       int slot;
+       struct btrfs_key cpukey;
+       u32 nritems = btrfs_header_nritems(node);
 
        if (path->nodes[level + 1])
-               parent = &path->nodes[level + 1]->node;
-       parent_slot = path->slots[level + 1];
-       if (parent && node->header.nritems > 0) {
-               struct key *parent_key;
-               parent_key = &parent->keys[parent_slot];
-               BUG_ON(memcmp(parent_key, node->keys, sizeof(struct key)));
-               BUG_ON(parent->blockptrs[parent_slot] != node->header.blocknr);
-       }
-       BUG_ON(node->header.nritems > NODEPTRS_PER_BLOCK);
-       for (i = 0; i < node->header.nritems - 2; i++) {
-               BUG_ON(comp_keys(&node->keys[i], &node->keys[i+1]) >= 0);
+               parent = path->nodes[level + 1];
+
+       slot = path->slots[level];
+       BUG_ON(nritems == 0);
+       if (parent) {
+               parent_slot = path->slots[level + 1];
+               btrfs_node_key(parent, &parent_key, parent_slot);
+               btrfs_node_key(node, &node_key, 0);
+               BUG_ON(memcmp(&parent_key, &node_key,
+                             sizeof(struct btrfs_disk_key)));
+               BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
+                      btrfs_header_blocknr(node));
+       }
+       BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root));
+       if (slot != 0) {
+               btrfs_node_key_to_cpu(node, &cpukey, slot - 1);
+               btrfs_node_key(node, &node_key, slot);
+               BUG_ON(comp_keys(&node_key, &cpukey) <= 0);
+       }
+       if (slot < nritems - 1) {
+               btrfs_node_key_to_cpu(node, &cpukey, slot + 1);
+               btrfs_node_key(node, &node_key, slot);
+               BUG_ON(comp_keys(&node_key, &cpukey) >= 0);
        }
        return 0;
 }
 
-int check_leaf(struct ctree_path *path, int level)
+static int check_leaf(struct btrfs_root *root, struct btrfs_path *path,
+                     int level)
 {
-       int i;
-       struct leaf *leaf = &path->nodes[level]->leaf;
-       struct node *parent = NULL;
+       struct extent_buffer *leaf = path->nodes[level];
+       struct extent_buffer *parent = NULL;
        int parent_slot;
+       struct btrfs_key cpukey;
+       struct btrfs_disk_key parent_key;
+       struct btrfs_disk_key leaf_key;
+       int slot = path->slots[0];
+
+       u32 nritems = btrfs_header_nritems(leaf);
 
        if (path->nodes[level + 1])
-               parent = &path->nodes[level + 1]->node;
-       parent_slot = path->slots[level + 1];
-       if (parent && leaf->header.nritems > 0) {
-               struct key *parent_key;
-               parent_key = &parent->keys[parent_slot];
-               BUG_ON(memcmp(parent_key, &leaf->items[0].key,
-                      sizeof(struct key)));
-               BUG_ON(parent->blockptrs[parent_slot] != leaf->header.blocknr);
-       }
-       for (i = 0; i < leaf->header.nritems - 2; i++) {
-               BUG_ON(comp_keys(&leaf->items[i].key,
-                                &leaf->items[i+1].key) >= 0);
-               BUG_ON(leaf->items[i].offset != leaf->items[i + 1].offset +
-                   leaf->items[i + 1].size);
+               parent = path->nodes[level + 1];
+
+       if (nritems == 0)
+               return 0;
+
+       if (parent) {
+               parent_slot = path->slots[level + 1];
+               btrfs_node_key(parent, &parent_key, parent_slot);
+               btrfs_item_key(leaf, &leaf_key, 0);
+
+               BUG_ON(memcmp(&parent_key, &leaf_key,
+                      sizeof(struct btrfs_disk_key)));
+               BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
+                      btrfs_header_blocknr(leaf));
+       }
+#if 0
+       for (i = 0; nritems > 1 && i < nritems - 2; i++) {
+               btrfs_item_key_to_cpu(leaf, &cpukey, i + 1);
+               btrfs_item_key(leaf, &leaf_key, i);
+               if (comp_keys(&leaf_key, &cpukey) >= 0) {
+                       btrfs_print_leaf(root, leaf);
+                       printk("slot %d offset bad key\n", i);
+                       BUG_ON(1);
+               }
+               if (btrfs_item_offset_nr(leaf, i) !=
+                       btrfs_item_end_nr(leaf, i + 1)) {
+                       btrfs_print_leaf(root, leaf);
+                       printk("slot %d offset bad\n", i);
+                       BUG_ON(1);
+               }
                if (i == 0) {
-                       BUG_ON(leaf->items[i].offset + leaf->items[i].size !=
-                               LEAF_DATA_SIZE);
+                       if (btrfs_item_offset_nr(leaf, i) +
+                              btrfs_item_size_nr(leaf, i) !=
+                              BTRFS_LEAF_DATA_SIZE(root)) {
+                               btrfs_print_leaf(root, leaf);
+                               printk("slot %d first offset bad\n", i);
+                               BUG_ON(1);
+                       }
+               }
+       }
+       if (nritems > 0) {
+               if (btrfs_item_size_nr(leaf, nritems - 1) > 4096) {
+                               btrfs_print_leaf(root, leaf);
+                               printk("slot %d bad size \n", nritems - 1);
+                               BUG_ON(1);
                }
        }
-       BUG_ON(leaf_free_space(leaf) < 0);
+#endif
+       if (slot != 0 && slot < nritems - 1) {
+               btrfs_item_key(leaf, &leaf_key, slot);
+               btrfs_item_key_to_cpu(leaf, &cpukey, slot - 1);
+               if (comp_keys(&leaf_key, &cpukey) <= 0) {
+                       btrfs_print_leaf(root, leaf);
+                       printk("slot %d offset bad key\n", slot);
+                       BUG_ON(1);
+               }
+               if (btrfs_item_offset_nr(leaf, slot - 1) !=
+                      btrfs_item_end_nr(leaf, slot)) {
+                       btrfs_print_leaf(root, leaf);
+                       printk("slot %d offset bad\n", slot);
+                       BUG_ON(1);
+               }
+       }
+       if (slot < nritems - 1) {
+               btrfs_item_key(leaf, &leaf_key, slot);
+               btrfs_item_key_to_cpu(leaf, &cpukey, slot + 1);
+               BUG_ON(comp_keys(&leaf_key, &cpukey) >= 0);
+               if (btrfs_item_offset_nr(leaf, slot) !=
+                       btrfs_item_end_nr(leaf, slot + 1)) {
+                       btrfs_print_leaf(root, leaf);
+                       printk("slot %d offset bad\n", slot);
+                       BUG_ON(1);
+               }
+       }
+       BUG_ON(btrfs_item_offset_nr(leaf, 0) +
+              btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root));
        return 0;
 }
 
-int check_block(struct ctree_path *path, int level)
+static int check_block(struct btrfs_root *root, struct btrfs_path *path,
+                       int level)
 {
+       struct extent_buffer *buf = path->nodes[level];
+
+       if (memcmp_extent_buffer(buf, root->fs_info->fsid,
+                                (unsigned long)btrfs_header_fsid(buf),
+                                BTRFS_FSID_SIZE)) {
+               printk("warning bad block %Lu\n", buf->start);
+               BUG();
+       }
        if (level == 0)
-               return check_leaf(path, level);
-       return check_node(path, level);
+               return check_leaf(root, path, level);
+       return check_node(root, path, level);
 }
 
 /*
- * search for key in the array p.  items p are item_size apart
- * and there are 'max' items in p
+ * search for key in the extent_buffer.  The items start at offset p,
+ * and they are item_size apart.  There are 'max' items in p.
+ *
  * the slot in the array is returned via slot, and it points to
  * the place where you would insert key if it is not found in
  * the array.
  *
  * slot may point to max if the key is bigger than all of the keys
  */
-int generic_bin_search(char *p, int item_size, struct key *key,
-                      int max, int *slot)
+static int generic_bin_search(struct extent_buffer *eb, unsigned long p,
+                             int item_size, struct btrfs_key *key,
+                             int max, int *slot)
 {
        int low = 0;
        int high = max;
        int mid;
        int ret;
-       struct key *tmp;
+       struct btrfs_disk_key *tmp = NULL;
+       struct btrfs_disk_key unaligned;
+       unsigned long offset;
+       char *map_token = NULL;
+       char *kaddr = NULL;
+       unsigned long map_start = 0;
+       unsigned long map_len = 0;
+       int err;
 
        while(low < high) {
                mid = (low + high) / 2;
-               tmp = (struct key *)(p + mid * item_size);
+               offset = p + mid * item_size;
+
+               if (!map_token || offset < map_start ||
+                   (offset + sizeof(struct btrfs_disk_key)) >
+                   map_start + map_len) {
+                       if (map_token) {
+                               unmap_extent_buffer(eb, map_token, KM_USER0);
+                               map_token = NULL;
+                       }
+                       err = map_extent_buffer(eb, offset,
+                                               sizeof(struct btrfs_disk_key),
+                                               &map_token, &kaddr,
+                                               &map_start, &map_len, KM_USER0);
+
+                       if (!err) {
+                               tmp = (struct btrfs_disk_key *)(kaddr + offset -
+                                                       map_start);
+                       } else {
+                               read_extent_buffer(eb, &unaligned,
+                                                  offset, sizeof(unaligned));
+                               tmp = &unaligned;
+                       }
+
+               } else {
+                       tmp = (struct btrfs_disk_key *)(kaddr + offset -
+                                                       map_start);
+               }
                ret = comp_keys(tmp, key);
 
                if (ret < 0)
@@ -170,10 +540,14 @@ int generic_bin_search(char *p, int item_size, struct key *key,
                        high = mid;
                else {
                        *slot = mid;
+                       if (map_token)
+                               unmap_extent_buffer(eb, map_token, KM_USER0);
                        return 0;
                }
        }
        *slot = low;
+       if (map_token)
+               unmap_extent_buffer(eb, map_token, KM_USER0);
        return 1;
 }
 
@@ -181,124 +555,147 @@ int generic_bin_search(char *p, int item_size, struct key *key,
  * simple bin_search frontend that does the right thing for
  * leaves vs nodes
  */
-int bin_search(struct node *c, struct key *key, int *slot)
+static int bin_search(struct extent_buffer *eb, struct btrfs_key *key,
+                     int level, 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);
+       if (level == 0) {
+               return generic_bin_search(eb,
+                                         offsetof(struct btrfs_leaf, items),
+                                         sizeof(struct btrfs_item),
+                                         key, btrfs_header_nritems(eb),
+                                         slot);
        } else {
-               return generic_bin_search((void *)c->keys, sizeof(struct key),
-                                         key, c->header.nritems, slot);
+               return generic_bin_search(eb,
+                                         offsetof(struct btrfs_node, ptrs),
+                                         sizeof(struct btrfs_key_ptr),
+                                         key, btrfs_header_nritems(eb),
+                                         slot);
        }
        return -1;
 }
 
-struct tree_buffer *read_node_slot(struct ctree_root *root,
-                                  struct tree_buffer *parent_buf,
-                                  int slot)
+static struct extent_buffer *read_node_slot(struct btrfs_root *root,
+                                  struct extent_buffer *parent, int slot)
 {
-       struct node *node = &parent_buf->node;
        if (slot < 0)
                return NULL;
-       if (slot >= node->header.nritems)
+       if (slot >= btrfs_header_nritems(parent))
                return NULL;
-       return read_tree_block(root, node->blockptrs[slot]);
+       return read_tree_block(root, btrfs_node_blockptr(parent, slot));
 }
 
-static int balance_level(struct ctree_root *root, struct ctree_path *path,
-                       int level)
+static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root
+                        *root, struct btrfs_path *path, int level)
 {
-       struct tree_buffer *right_buf;
-       struct tree_buffer *mid_buf;
-       struct tree_buffer *left_buf;
-       struct tree_buffer *parent_buf = NULL;
-       struct node *right = NULL;
-       struct node *mid;
-       struct node *left = NULL;
-       struct node *parent = NULL;
+       struct extent_buffer *right = NULL;
+       struct extent_buffer *mid;
+       struct extent_buffer *left = NULL;
+       struct extent_buffer *parent = NULL;
        int ret = 0;
        int wret;
        int pslot;
        int orig_slot = path->slots[level];
+       int err_on_enospc = 0;
        u64 orig_ptr;
 
        if (level == 0)
                return 0;
 
-       mid_buf = path->nodes[level];
-       mid = &mid_buf->node;
-       orig_ptr = mid->blockptrs[orig_slot];
+       mid = path->nodes[level];
+       orig_ptr = btrfs_node_blockptr(mid, orig_slot);
 
-       if (level < MAX_LEVEL - 1)
-               parent_buf = path->nodes[level + 1];
+       if (level < BTRFS_MAX_LEVEL - 1)
+               parent = path->nodes[level + 1];
        pslot = path->slots[level + 1];
 
-       if (!parent_buf) {
-               struct tree_buffer *child;
-               u64 blocknr = mid_buf->blocknr;
+       /*
+        * deal with the case where there is only one pointer in the root
+        * by promoting the node below to a root
+        */
+       if (!parent) {
+               struct extent_buffer *child;
+               u64 blocknr = extent_buffer_blocknr(mid);
 
-               if (mid->header.nritems != 1)
+               if (btrfs_header_nritems(mid) != 1)
                        return 0;
 
                /* promote the child to a root */
-               child = read_node_slot(root, mid_buf, 0);
+               child = read_node_slot(root, mid, 0);
                BUG_ON(!child);
                root->node = child;
                path->nodes[level] = NULL;
+               clean_tree_block(trans, root, mid);
+               wait_on_tree_block_writeback(root, mid);
                /* once for the path */
-               tree_block_release(root, mid_buf);
+               free_extent_buffer(mid);
                /* once for the root ptr */
-               tree_block_release(root, mid_buf);
-               clean_tree_block(root, mid_buf);
-               return free_extent(root, blocknr, 1);
+               free_extent_buffer(mid);
+               return btrfs_free_extent(trans, root, blocknr, 1, 1);
        }
-       parent = &parent_buf->node;
-
-       if (mid->header.nritems > NODEPTRS_PER_BLOCK / 4)
+       if (btrfs_header_nritems(mid) >
+           BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
                return 0;
 
-       left_buf = read_node_slot(root, parent_buf, pslot - 1);
-       right_buf = read_node_slot(root, parent_buf, pslot + 1);
+       if (btrfs_header_nritems(mid) < 2)
+               err_on_enospc = 1;
+
+       left = read_node_slot(root, parent, pslot - 1);
+       if (left) {
+               wret = btrfs_cow_block(trans, root, left,
+                                      parent, pslot - 1, &left);
+               if (wret) {
+                       ret = wret;
+                       goto enospc;
+               }
+       }
+       right = read_node_slot(root, parent, pslot + 1);
+       if (right) {
+               wret = btrfs_cow_block(trans, root, right,
+                                      parent, pslot + 1, &right);
+               if (wret) {
+                       ret = wret;
+                       goto enospc;
+               }
+       }
 
        /* first, try to make some room in the middle buffer */
-       if (left_buf) {
-               left = &left_buf->node;
-               orig_slot += left->header.nritems;
-               wret = push_node_left(root, left_buf, mid_buf);
+       if (left) {
+               orig_slot += btrfs_header_nritems(left);
+               wret = push_node_left(trans, root, left, mid);
                if (wret < 0)
                        ret = wret;
+               if (btrfs_header_nritems(mid) < 2)
+                       err_on_enospc = 1;
        }
 
        /*
         * then try to empty the right most buffer into the middle
         */
-       if (right_buf) {
-               right = &right_buf->node;
-               wret = push_node_left(root, mid_buf, right_buf);
-               if (wret < 0)
+       if (right) {
+               wret = push_node_left(trans, root, mid, right);
+               if (wret < 0 && wret != -ENOSPC)
                        ret = wret;
-               if (right->header.nritems == 0) {
-                       u64 blocknr = right_buf->blocknr;
-                       tree_block_release(root, right_buf);
-                       clean_tree_block(root, right_buf);
-                       right_buf = NULL;
+               if (btrfs_header_nritems(right) == 0) {
+                       u64 blocknr = extent_buffer_blocknr(right);
+                       clean_tree_block(trans, root, right);
+                       wait_on_tree_block_writeback(root, right);
+                       free_extent_buffer(right);
                        right = NULL;
-                       wret = del_ptr(root, path, level + 1, pslot + 1);
+                       wret = del_ptr(trans, root, path, level + 1, pslot +
+                                      1);
                        if (wret)
                                ret = wret;
-                       wret = free_extent(root, blocknr, 1);
+                       wret = btrfs_free_extent(trans, root, blocknr, 1, 1);
                        if (wret)
                                ret = wret;
                } else {
-                       memcpy(parent->keys + pslot + 1, right->keys,
-                               sizeof(struct key));
-                       wret = dirty_tree_block(root, parent_buf);
-                       if (wret)
-                               ret = wret;
+                       struct btrfs_disk_key right_key;
+                       btrfs_node_key(right, &right_key, 0);
+                       btrfs_set_node_key(parent, &right_key, pslot + 1);
+                       btrfs_mark_buffer_dirty(parent);
                }
        }
-       if (mid->header.nritems == 1) {
+       if (btrfs_header_nritems(mid) == 1) {
                /*
                 * we're not allowed to leave a node with one item in the
                 * tree during a delete.  A deletion from lower in the tree
@@ -308,59 +705,242 @@ static int balance_level(struct ctree_root *root, struct ctree_path *path,
                 * otherwise we would have pulled some pointers from the
                 * right
                 */
-               BUG_ON(!left_buf);
-               wret = balance_node_right(root, mid_buf, left_buf);
-               if (wret < 0)
+               BUG_ON(!left);
+               wret = balance_node_right(trans, root, mid, left);
+               if (wret < 0) {
                        ret = wret;
+                       goto enospc;
+               }
                BUG_ON(wret == 1);
        }
-       if (mid->header.nritems == 0) {
+       if (btrfs_header_nritems(mid) == 0) {
                /* we've managed to empty the middle node, drop it */
-               u64 blocknr = mid_buf->blocknr;
-               tree_block_release(root, mid_buf);
-               clean_tree_block(root, mid_buf);
-               mid_buf = NULL;
+               u64 blocknr = extent_buffer_blocknr(mid);
+               clean_tree_block(trans, root, mid);
+               wait_on_tree_block_writeback(root, mid);
+               free_extent_buffer(mid);
                mid = NULL;
-               wret = del_ptr(root, path, level + 1, pslot);
+               wret = del_ptr(trans, root, path, level + 1, pslot);
                if (wret)
                        ret = wret;
-               wret = free_extent(root, blocknr, 1);
+               wret = btrfs_free_extent(trans, root, blocknr, 1, 1);
                if (wret)
                        ret = wret;
        } else {
                /* update the parent key to reflect our changes */
-               memcpy(parent->keys + pslot, mid->keys, sizeof(struct key));
-               wret = dirty_tree_block(root, parent_buf);
-               if (wret)
-                       ret = wret;
+               struct btrfs_disk_key mid_key;
+               btrfs_node_key(mid, &mid_key, 0);
+               btrfs_set_node_key(parent, &mid_key, pslot);
+               btrfs_mark_buffer_dirty(parent);
        }
 
        /* update the path */
-       if (left_buf) {
-               if (left->header.nritems > orig_slot) {
-                       left_buf->count++; // released below
-                       path->nodes[level] = left_buf;
+       if (left) {
+               if (btrfs_header_nritems(left) > orig_slot) {
+                       extent_buffer_get(left);
+                       path->nodes[level] = left;
                        path->slots[level + 1] -= 1;
                        path->slots[level] = orig_slot;
-                       if (mid_buf)
-                               tree_block_release(root, mid_buf);
+                       if (mid)
+                               free_extent_buffer(mid);
                } else {
-                       orig_slot -= left->header.nritems;
+                       orig_slot -= btrfs_header_nritems(left);
                        path->slots[level] = orig_slot;
                }
        }
        /* double check we haven't messed things up */
-       check_block(path, level);
-       if (orig_ptr != path->nodes[level]->node.blockptrs[path->slots[level]])
+       check_block(root, path, level);
+       if (orig_ptr !=
+           btrfs_node_blockptr(path->nodes[level], path->slots[level]))
                BUG();
-
-       if (right_buf)
-               tree_block_release(root, right_buf);
-       if (left_buf)
-               tree_block_release(root, left_buf);
+enospc:
+       if (right)
+               free_extent_buffer(right);
+       if (left)
+               free_extent_buffer(left);
        return ret;
 }
 
+/* returns zero if the push worked, non-zero otherwise */
+static int push_nodes_for_insert(struct btrfs_trans_handle *trans,
+                               struct btrfs_root *root,
+                               struct btrfs_path *path, int level)
+{
+       struct extent_buffer *right = NULL;
+       struct extent_buffer *mid;
+       struct extent_buffer *left = NULL;
+       struct extent_buffer *parent = NULL;
+       int ret = 0;
+       int wret;
+       int pslot;
+       int orig_slot = path->slots[level];
+       u64 orig_ptr;
+
+       if (level == 0)
+               return 1;
+
+       mid = path->nodes[level];
+       orig_ptr = btrfs_node_blockptr(mid, orig_slot);
+
+       if (level < BTRFS_MAX_LEVEL - 1)
+               parent = path->nodes[level + 1];
+       pslot = path->slots[level + 1];
+
+       if (!parent)
+               return 1;
+
+       left = read_node_slot(root, parent, pslot - 1);
+
+       /* first, try to make some room in the middle buffer */
+       if (left) {
+               u32 left_nr;
+               left_nr = btrfs_header_nritems(left);
+               if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
+                       wret = 1;
+               } else {
+                       ret = btrfs_cow_block(trans, root, left, parent,
+                                             pslot - 1, &left);
+                       if (ret)
+                               wret = 1;
+                       else {
+                               wret = push_node_left(trans, root,
+                                                     left, mid);
+                       }
+               }
+               if (wret < 0)
+                       ret = wret;
+               if (wret == 0) {
+                       struct btrfs_disk_key disk_key;
+                       orig_slot += left_nr;
+                       btrfs_node_key(mid, &disk_key, 0);
+                       btrfs_set_node_key(parent, &disk_key, pslot);
+                       btrfs_mark_buffer_dirty(parent);
+                       if (btrfs_header_nritems(left) > orig_slot) {
+                               path->nodes[level] = left;
+                               path->slots[level + 1] -= 1;
+                               path->slots[level] = orig_slot;
+                               free_extent_buffer(mid);
+                       } else {
+                               orig_slot -=
+                                       btrfs_header_nritems(left);
+                               path->slots[level] = orig_slot;
+                               free_extent_buffer(left);
+                       }
+                       check_node(root, path, level);
+                       return 0;
+               }
+               free_extent_buffer(left);
+       }
+       right= read_node_slot(root, parent, pslot + 1);
+
+       /*
+        * then try to empty the right most buffer into the middle
+        */
+       if (right) {
+               u32 right_nr;
+               right_nr = btrfs_header_nritems(right);
+               if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
+                       wret = 1;
+               } else {
+                       ret = btrfs_cow_block(trans, root, right,
+                                             parent, pslot + 1,
+                                             &right);
+                       if (ret)
+                               wret = 1;
+                       else {
+                               wret = balance_node_right(trans, root,
+                                                         right, mid);
+                       }
+               }
+               if (wret < 0)
+                       ret = wret;
+               if (wret == 0) {
+                       struct btrfs_disk_key disk_key;
+
+                       btrfs_node_key(right, &disk_key, 0);
+                       btrfs_set_node_key(parent, &disk_key, pslot + 1);
+                       btrfs_mark_buffer_dirty(parent);
+
+                       if (btrfs_header_nritems(mid) <= orig_slot) {
+                               path->nodes[level] = right;
+                               path->slots[level + 1] += 1;
+                               path->slots[level] = orig_slot -
+                                       btrfs_header_nritems(mid);
+                               free_extent_buffer(mid);
+                       } else {
+                               free_extent_buffer(right);
+                       }
+                       check_node(root, path, level);
+                       return 0;
+               }
+               free_extent_buffer(right);
+       }
+       check_node(root, path, level);
+       return 1;
+}
+
+/*
+ * readahead one full node of leaves
+ */
+static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
+                            int level, int slot)
+{
+       struct extent_buffer *node;
+       int i;
+       u32 nritems;
+       u64 blocknr;
+       u64 search;
+       u64 cluster_start;
+       int ret;
+       int nread = 0;
+       int direction = path->reada;
+       struct radix_tree_root found;
+       unsigned long gang[8];
+       struct extent_buffer *eb;
+
+       if (level == 0)
+               return;
+
+       if (!path->nodes[level])
+               return;
+
+       node = path->nodes[level];
+       search = btrfs_node_blockptr(node, slot);
+       eb = btrfs_find_tree_block(root, search);
+       if (eb) {
+               free_extent_buffer(eb);
+               return;
+       }
+
+       init_bit_radix(&found);
+       nritems = btrfs_header_nritems(node);
+       for (i = slot; i < nritems; i++) {
+               blocknr = btrfs_node_blockptr(node, i);
+               set_radix_bit(&found, blocknr);
+       }
+       if (direction > 0) {
+               cluster_start = search - 4;
+               if (cluster_start > search)
+                       cluster_start = 0;
+       } else
+               cluster_start = search + 4;
+       while(1) {
+               ret = find_first_radix_bit(&found, gang, 0, ARRAY_SIZE(gang));
+               if (!ret)
+                       break;
+               for (i = 0; i < ret; i++) {
+                       blocknr = gang[i];
+                       clear_radix_bit(&found, blocknr);
+                       if (path->reada == 1 && nread > 16)
+                               continue;
+                       if (close_blocks(cluster_start, blocknr)) {
+                               readahead_tree_block(root, blocknr);
+                               nread++;
+                               cluster_start = blocknr;
+                       }
+               }
+       }
+}
 /*
  * look for key in the tree.  path is filled in with nodes along the way
  * if key is found, we return zero and you can find the item in the leaf
@@ -374,66 +954,90 @@ static int balance_level(struct ctree_root *root, struct ctree_path *path,
  * tree.  if ins_len < 0, nodes will be merged as we walk down the tree (if
  * possible)
  */
-int search_slot(struct ctree_root *root, struct key *key,
-               struct ctree_path *p, int ins_len)
+int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_key *key, struct btrfs_path *p, int
+                     ins_len, int cow)
 {
-       struct tree_buffer *b;
-       struct node *c;
+       struct extent_buffer *b;
+       u64 blocknr;
        int slot;
        int ret;
        int level;
+       int should_reada = p->reada;
+       u8 lowest_level = 0;
 
+       lowest_level = p->lowest_level;
+       WARN_ON(lowest_level && ins_len);
+       WARN_ON(p->nodes[0] != NULL);
+       WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
 again:
        b = root->node;
-       b->count++;
+       extent_buffer_get(b);
        while (b) {
-               c = &b->node;
-               level = node_level(c->header.flags);
+               level = btrfs_header_level(b);
+               if (cow) {
+                       int wret;
+                       wret = btrfs_cow_block(trans, root, b,
+                                              p->nodes[level + 1],
+                                              p->slots[level + 1],
+                                              &b);
+                       if (wret) {
+                               free_extent_buffer(b);
+                               return wret;
+                       }
+               }
+               BUG_ON(!cow && ins_len);
+               if (level != btrfs_header_level(b))
+                       WARN_ON(1);
+               level = btrfs_header_level(b);
                p->nodes[level] = b;
-               ret = check_block(p, level);
+               ret = check_block(root, p, level);
                if (ret)
                        return -1;
-               ret = bin_search(c, key, &slot);
-               if (!is_leaf(c->header.flags)) {
+               ret = bin_search(b, key, level, &slot);
+               if (level != 0) {
                        if (ret && slot > 0)
                                slot -= 1;
                        p->slots[level] = slot;
-                       if (ins_len > 0 &&
-                           c->header.nritems == NODEPTRS_PER_BLOCK) {
-                               int sret = split_node(root, p, level);
+                       if (ins_len > 0 && btrfs_header_nritems(b) >=
+                           BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
+                               int sret = split_node(trans, root, p, level);
                                BUG_ON(sret > 0);
                                if (sret)
                                        return sret;
                                b = p->nodes[level];
-                               c = &b->node;
                                slot = p->slots[level];
                        } else if (ins_len < 0) {
-                               int sret = balance_level(root, p, level);
+                               int sret = balance_level(trans, root, p,
+                                                        level);
                                if (sret)
                                        return sret;
                                b = p->nodes[level];
                                if (!b)
                                        goto again;
-                               c = &b->node;
                                slot = p->slots[level];
-                               BUG_ON(c->header.nritems == 1);
+                               BUG_ON(btrfs_header_nritems(b) == 1);
                        }
-                       b = read_tree_block(root, c->blockptrs[slot]);
+                       /* this is only true while dropping a snapshot */
+                       if (level == lowest_level)
+                               break;
+                       blocknr = btrfs_node_blockptr(b, slot);
+                       if (should_reada)
+                               reada_for_search(root, p, level, slot);
+                       b = read_tree_block(root, btrfs_node_blockptr(b, slot));
                } else {
-                       struct leaf *l = (struct leaf *)c;
                        p->slots[level] = slot;
-                       if (ins_len > 0 && leaf_free_space(l) <
-                           sizeof(struct item) + ins_len) {
-                               int sret = split_leaf(root, p, ins_len);
+                       if (ins_len > 0 && btrfs_leaf_free_space(root, b) <
+                           sizeof(struct btrfs_item) + ins_len) {
+                               int sret = split_leaf(trans, root, key,
+                                                     p, ins_len);
                                BUG_ON(sret > 0);
                                if (sret)
                                        return sret;
                        }
-                       BUG_ON(root->node->count == 1);
                        return ret;
                }
        }
-       BUG_ON(root->node->count == 1);
        return 1;
 }
 
@@ -447,23 +1051,21 @@ again:
  * If this fails to write a tree block, it returns -1, but continues
  * fixing up the blocks in ram so the tree is consistent.
  */
-static int fixup_low_keys(struct ctree_root *root,
-                          struct ctree_path *path, struct key *key,
-                          int level)
+static int fixup_low_keys(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root, struct btrfs_path *path,
+                         struct btrfs_disk_key *key, int level)
 {
        int i;
        int ret = 0;
-       int wret;
-       for (i = level; i < MAX_LEVEL; i++) {
-               struct node *t;
+       struct extent_buffer *t;
+
+       for (i = level; i < BTRFS_MAX_LEVEL; i++) {
                int tslot = path->slots[i];
                if (!path->nodes[i])
                        break;
-               t = &path->nodes[i]->node;
-               memcpy(t->keys + tslot, key, sizeof(*key));
-               wret = dirty_tree_block(root, path->nodes[i]);
-               if (wret)
-                       ret = wret;
+               t = path->nodes[i];
+               btrfs_set_node_key(t, key, tslot);
+               btrfs_mark_buffer_dirty(path->nodes[i]);
                if (tslot != 0)
                        break;
        }
@@ -477,20 +1079,19 @@ static int fixup_low_keys(struct ctree_root *root,
  * returns 0 if some ptrs were pushed left, < 0 if there was some horrible
  * error, and > 0 if there was no room in the left hand block.
  */
-static int push_node_left(struct ctree_root *root, struct tree_buffer *dst_buf,
-                         struct tree_buffer *src_buf)
+static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root
+                         *root, struct extent_buffer *dst,
+                         struct extent_buffer *src)
 {
-       struct node *src = &src_buf->node;
-       struct node *dst = &dst_buf->node;
        int push_items = 0;
        int src_nritems;
        int dst_nritems;
        int ret = 0;
-       int wret;
 
-       src_nritems = src->header.nritems;
-       dst_nritems = dst->header.nritems;
-       push_items = NODEPTRS_PER_BLOCK - dst_nritems;
+       src_nritems = btrfs_header_nritems(src);
+       dst_nritems = btrfs_header_nritems(dst);
+       push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems;
+
        if (push_items <= 0) {
                return 1;
        }
@@ -498,26 +1099,21 @@ static int push_node_left(struct ctree_root *root, struct tree_buffer *dst_buf,
        if (src_nritems < push_items)
                push_items = src_nritems;
 
-       memcpy(dst->keys + dst_nritems, src->keys,
-               push_items * sizeof(struct key));
-       memcpy(dst->blockptrs + dst_nritems, src->blockptrs,
-               push_items * sizeof(u64));
+       copy_extent_buffer(dst, src,
+                          btrfs_node_key_ptr_offset(dst_nritems),
+                          btrfs_node_key_ptr_offset(0),
+                          push_items * sizeof(struct btrfs_key_ptr));
+
        if (push_items < src_nritems) {
-               memmove(src->keys, src->keys + push_items,
-                       (src_nritems - push_items) * sizeof(struct key));
-               memmove(src->blockptrs, src->blockptrs + push_items,
-                       (src_nritems - push_items) * sizeof(u64));
+               memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0),
+                                     btrfs_node_key_ptr_offset(push_items),
+                                     (src_nritems - push_items) *
+                                     sizeof(struct btrfs_key_ptr));
        }
-       src->header.nritems -= push_items;
-       dst->header.nritems += push_items;
-
-       wret = dirty_tree_block(root, src_buf);
-       if (wret < 0)
-               ret = wret;
-
-       wret = dirty_tree_block(root, dst_buf);
-       if (wret < 0)
-               ret = wret;
+       btrfs_set_header_nritems(src, src_nritems - push_items);
+       btrfs_set_header_nritems(dst, dst_nritems + push_items);
+       btrfs_mark_buffer_dirty(src);
+       btrfs_mark_buffer_dirty(dst);
        return ret;
 }
 
@@ -530,52 +1126,46 @@ static int push_node_left(struct ctree_root *root, struct tree_buffer *dst_buf,
  *
  * this will  only push up to 1/2 the contents of the left node over
  */
-static int balance_node_right(struct ctree_root *root,
-                             struct tree_buffer *dst_buf,
-                             struct tree_buffer *src_buf)
+static int balance_node_right(struct btrfs_trans_handle *trans,
+                             struct btrfs_root *root,
+                             struct extent_buffer *dst,
+                             struct extent_buffer *src)
 {
-       struct node *src = &src_buf->node;
-       struct node *dst = &dst_buf->node;
        int push_items = 0;
        int max_push;
        int src_nritems;
        int dst_nritems;
        int ret = 0;
-       int wret;
 
-       src_nritems = src->header.nritems;
-       dst_nritems = dst->header.nritems;
-       push_items = NODEPTRS_PER_BLOCK - dst_nritems;
-       if (push_items <= 0) {
+       src_nritems = btrfs_header_nritems(src);
+       dst_nritems = btrfs_header_nritems(dst);
+       push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems;
+       if (push_items <= 0)
                return 1;
-       }
 
        max_push = src_nritems / 2 + 1;
        /* don't try to empty the node */
-       if (max_push > src_nritems)
+       if (max_push >= src_nritems)
                return 1;
+
        if (max_push < push_items)
                push_items = max_push;
 
-       memmove(dst->keys + push_items, dst->keys,
-               dst_nritems * sizeof(struct key));
-       memmove(dst->blockptrs + push_items, dst->blockptrs,
-               dst_nritems * sizeof(u64));
-       memcpy(dst->keys, src->keys + src_nritems - push_items,
-               push_items * sizeof(struct key));
-       memcpy(dst->blockptrs, src->blockptrs + src_nritems - push_items,
-               push_items * sizeof(u64));
+       memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items),
+                                     btrfs_node_key_ptr_offset(0),
+                                     (dst_nritems) *
+                                     sizeof(struct btrfs_key_ptr));
 
-       src->header.nritems -= push_items;
-       dst->header.nritems += push_items;
+       copy_extent_buffer(dst, src,
+                          btrfs_node_key_ptr_offset(0),
+                          btrfs_node_key_ptr_offset(src_nritems - push_items),
+                          push_items * sizeof(struct btrfs_key_ptr));
 
-       wret = dirty_tree_block(root, src_buf);
-       if (wret < 0)
-               ret = wret;
+       btrfs_set_header_nritems(src, src_nritems - push_items);
+       btrfs_set_header_nritems(dst, dst_nritems + push_items);
 
-       wret = dirty_tree_block(root, dst_buf);
-       if (wret < 0)
-               ret = wret;
+       btrfs_mark_buffer_dirty(src);
+       btrfs_mark_buffer_dirty(dst);
        return ret;
 }
 
@@ -586,37 +1176,46 @@ static int balance_node_right(struct ctree_root *root,
  *
  * returns zero on success or < 0 on failure.
  */
-static int insert_new_root(struct ctree_root *root,
-                          struct ctree_path *path, int level)
+static int insert_new_root(struct btrfs_trans_handle *trans,
+                          struct btrfs_root *root,
+                          struct btrfs_path *path, int level)
 {
-       struct tree_buffer *t;
-       struct node *lower;
-       struct node *c;
-       struct key *lower_key;
+       struct extent_buffer *lower;
+       struct extent_buffer *c;
+       struct btrfs_disk_key lower_key;
 
        BUG_ON(path->nodes[level]);
        BUG_ON(path->nodes[level-1] != root->node);
 
-       t = alloc_free_block(root);
-       c = &t->node;
-       memset(c, 0, sizeof(c));
-       c->header.nritems = 1;
-       c->header.flags = node_level(level);
-       c->header.blocknr = t->blocknr;
-       c->header.parentid = root->node->node.header.parentid;
-       lower = &path->nodes[level-1]->node;
-       if (is_leaf(lower->header.flags))
-               lower_key = &((struct leaf *)lower)->items[0].key;
+       c = btrfs_alloc_free_block(trans, root,
+                                  extent_buffer_blocknr(root->node), 0);
+       if (IS_ERR(c))
+               return PTR_ERR(c);
+       memset_extent_buffer(c, 0, 0, root->nodesize);
+       btrfs_set_header_nritems(c, 1);
+       btrfs_set_header_level(c, level);
+       btrfs_set_header_blocknr(c, extent_buffer_blocknr(c));
+       btrfs_set_header_generation(c, trans->transid);
+       btrfs_set_header_owner(c, root->root_key.objectid);
+       lower = path->nodes[level-1];
+
+       write_extent_buffer(c, root->fs_info->fsid,
+                           (unsigned long)btrfs_header_fsid(c),
+                           BTRFS_FSID_SIZE);
+       if (level == 1)
+               btrfs_item_key(lower, &lower_key, 0);
        else
-               lower_key = lower->keys;
-       memcpy(c->keys, lower_key, sizeof(struct key));
-       c->blockptrs[0] = path->nodes[level-1]->blocknr;
+               btrfs_node_key(lower, &lower_key, 0);
+       btrfs_set_node_key(c, &lower_key, 0);
+       btrfs_set_node_blockptr(c, 0, extent_buffer_blocknr(lower));
+
+       btrfs_mark_buffer_dirty(c);
+
        /* the super has an extra ref to root->node */
-       tree_block_release(root, root->node);
-       root->node = t;
-       t->count++;
-       dirty_tree_block(root, t);
-       path->nodes[level] = t;
+       free_extent_buffer(root->node);
+       root->node = c;
+       extent_buffer_get(c);
+       path->nodes[level] = c;
        path->slots[level] = 0;
        return 0;
 }
@@ -630,32 +1229,31 @@ static int insert_new_root(struct ctree_root *root,
  *
  * returns zero on success and < 0 on any error
  */
-static int insert_ptr(struct ctree_root *root,
-               struct ctree_path *path, struct key *key,
-               u64 blocknr, int slot, int level)
+static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_path *path, struct btrfs_disk_key
+                     *key, u64 blocknr, int slot, int level)
 {
-       struct node *lower;
+       struct extent_buffer *lower;
        int nritems;
 
        BUG_ON(!path->nodes[level]);
-       lower = &path->nodes[level]->node;
-       nritems = lower->header.nritems;
+       lower = path->nodes[level];
+       nritems = btrfs_header_nritems(lower);
        if (slot > nritems)
                BUG();
-       if (nritems == NODEPTRS_PER_BLOCK)
+       if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root))
                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();
-       dirty_tree_block(root, path->nodes[level]);
+               memmove_extent_buffer(lower,
+                             btrfs_node_key_ptr_offset(slot + 1),
+                             btrfs_node_key_ptr_offset(slot),
+                             (nritems - slot) * sizeof(struct btrfs_key_ptr));
+       }
+       btrfs_set_node_key(lower, key, slot);
+       btrfs_set_node_blockptr(lower, slot, blocknr);
+       btrfs_set_header_nritems(lower, nritems + 1);
+       btrfs_mark_buffer_dirty(lower);
+       check_node(root, path, level);
        return 0;
 }
 
@@ -668,57 +1266,76 @@ static int insert_ptr(struct ctree_root *root,
  *
  * returns 0 on success and < 0 on failure
  */
-static int split_node(struct ctree_root *root, struct ctree_path *path,
-                     int level)
+static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_path *path, int level)
 {
-       struct tree_buffer *t;
-       struct node *c;
-       struct tree_buffer *split_buffer;
-       struct node *split;
+       struct extent_buffer *c;
+       struct extent_buffer *split;
+       struct btrfs_disk_key disk_key;
        int mid;
        int ret;
        int wret;
+       u32 c_nritems;
 
-       t = path->nodes[level];
-       c = &t->node;
-       if (t == root->node) {
+       c = path->nodes[level];
+       if (c == root->node) {
                /* trying to split the root, lets make a new one */
-               ret = insert_new_root(root, path, level + 1);
+               ret = insert_new_root(trans, root, path, level + 1);
                if (ret)
                        return ret;
+       } else {
+               ret = push_nodes_for_insert(trans, root, path, level);
+               c = path->nodes[level];
+               if (!ret && btrfs_header_nritems(c) <
+                   BTRFS_NODEPTRS_PER_BLOCK(root) - 1)
+                       return 0;
+               if (ret < 0)
+                       return ret;
        }
-       split_buffer = alloc_free_block(root);
-       split = &split_buffer->node;
-       split->header.flags = c->header.flags;
-       split->header.blocknr = split_buffer->blocknr;
-       split->header.parentid = root->node->node.header.parentid;
-       mid = (c->header.nritems + 1) / 2;
-       memcpy(split->keys, c->keys + mid,
-               (c->header.nritems - mid) * sizeof(struct key));
-       memcpy(split->blockptrs, c->blockptrs + mid,
-               (c->header.nritems - mid) * sizeof(u64));
-       split->header.nritems = c->header.nritems - mid;
-       c->header.nritems = mid;
+
+       c_nritems = btrfs_header_nritems(c);
+       split = btrfs_alloc_free_block(trans, root,
+                                      extent_buffer_blocknr(c), 0);
+       if (IS_ERR(split))
+               return PTR_ERR(split);
+
+       btrfs_set_header_flags(split, btrfs_header_flags(c));
+       btrfs_set_header_level(split, btrfs_header_level(c));
+       btrfs_set_header_blocknr(split, extent_buffer_blocknr(split));
+       btrfs_set_header_generation(split, trans->transid);
+       btrfs_set_header_owner(split, root->root_key.objectid);
+       write_extent_buffer(split, root->fs_info->fsid,
+                           (unsigned long)btrfs_header_fsid(split),
+                           BTRFS_FSID_SIZE);
+
+       mid = (c_nritems + 1) / 2;
+
+       copy_extent_buffer(split, c,
+                          btrfs_node_key_ptr_offset(0),
+                          btrfs_node_key_ptr_offset(mid),
+                          (c_nritems - mid) * sizeof(struct btrfs_key_ptr));
+       btrfs_set_header_nritems(split, c_nritems - mid);
+       btrfs_set_header_nritems(c, mid);
        ret = 0;
 
-       wret = dirty_tree_block(root, t);
-       if (wret)
-               ret = wret;
-       wret = dirty_tree_block(root, split_buffer);
-       if (wret)
-               ret = wret;
-       wret = insert_ptr(root, path, split->keys, split_buffer->blocknr,
-                         path->slots[level + 1] + 1, level + 1);
+       btrfs_mark_buffer_dirty(c);
+       btrfs_mark_buffer_dirty(split);
+
+       btrfs_node_key(split, &disk_key, 0);
+       wret = insert_ptr(trans, root, path, &disk_key,
+                         extent_buffer_blocknr(split),
+                         path->slots[level + 1] + 1,
+                         level + 1);
        if (wret)
                ret = wret;
 
        if (path->slots[level] >= mid) {
                path->slots[level] -= mid;
-               tree_block_release(root, t);
-               path->nodes[level] = split_buffer;
+               free_extent_buffer(c);
+               path->nodes[level] = split;
                path->slots[level + 1] += 1;
        } else {
-               tree_block_release(root, split_buffer);
+               free_extent_buffer(split);
        }
        return ret;
 }
@@ -728,19 +1345,39 @@ static int split_node(struct ctree_root *root, struct ctree_path *path,
  * and nr indicate which items in the leaf to check.  This totals up the
  * space used both by the item structs and the item data
  */
-static int leaf_space_used(struct leaf *l, int start, int nr)
+static int leaf_space_used(struct extent_buffer *l, int start, int nr)
 {
        int data_len;
-       int end = start + nr - 1;
+       int nritems = btrfs_header_nritems(l);
+       int end = min(nritems, 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;
+       data_len = btrfs_item_end_nr(l, start);
+       data_len = data_len - btrfs_item_offset_nr(l, end);
+       data_len += sizeof(struct btrfs_item) * nr;
+       WARN_ON(data_len < 0);
        return data_len;
 }
 
+/*
+ * The space between the end of the leaf items and
+ * the start of the leaf data.  IOW, how much room
+ * the leaf has left for both items and data
+ */
+int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf)
+{
+       int nritems = btrfs_header_nritems(leaf);
+       int ret;
+       ret = BTRFS_LEAF_DATA_SIZE(root) - leaf_space_used(leaf, 0, nritems);
+       if (ret < 0) {
+               printk("leaf free space ret %d, leaf data size %lu, used %d nritems %d\n",
+                      ret, BTRFS_LEAF_DATA_SIZE(root),
+                      leaf_space_used(leaf, 0, nritems), nritems);
+       }
+       return ret;
+}
+
 /*
  * push some data in the path leaf to the right, trying to free up at
  * least data_size bytes.  returns zero if the push worked, nonzero otherwise
@@ -748,192 +1385,281 @@ static int leaf_space_used(struct leaf *l, int start, int nr)
  * returns 1 if the push failed because the other node didn't have enough
  * room, 0 if everything worked out and < 0 if there were major errors.
  */
-static int push_leaf_right(struct ctree_root *root, struct ctree_path *path,
-                          int data_size)
+static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
+                          *root, struct btrfs_path *path, int data_size)
 {
-       struct tree_buffer *left_buf = path->nodes[0];
-       struct leaf *left = &left_buf->leaf;
-       struct leaf *right;
-       struct tree_buffer *right_buf;
-       struct tree_buffer *upper;
+       struct extent_buffer *left = path->nodes[0];
+       struct extent_buffer *right;
+       struct extent_buffer *upper;
+       struct btrfs_disk_key disk_key;
        int slot;
        int i;
        int free_space;
        int push_space = 0;
        int push_items = 0;
-       struct item *item;
+       struct btrfs_item *item;
+       u32 left_nritems;
+       u32 right_nritems;
+       u32 data_end;
+       int ret;
 
        slot = path->slots[1];
        if (!path->nodes[1]) {
                return 1;
        }
        upper = path->nodes[1];
-       if (slot >= upper->node.header.nritems - 1) {
+       if (slot >= btrfs_header_nritems(upper) - 1)
+               return 1;
+
+       right = read_tree_block(root, btrfs_node_blockptr(upper, slot + 1));
+       free_space = btrfs_leaf_free_space(root, right);
+       if (free_space < data_size + sizeof(struct btrfs_item)) {
+               free_extent_buffer(right);
                return 1;
        }
-       right_buf = read_tree_block(root, upper->node.blockptrs[slot + 1]);
-       right = &right_buf->leaf;
-       free_space = leaf_free_space(right);
-       if (free_space < data_size + sizeof(struct item)) {
-               tree_block_release(root, right_buf);
+
+       /* cow and double check */
+       ret = btrfs_cow_block(trans, root, right, upper,
+                             slot + 1, &right);
+       if (ret) {
+               free_extent_buffer(right);
+               return 1;
+       }
+       free_space = btrfs_leaf_free_space(root, right);
+       if (free_space < data_size + sizeof(struct btrfs_item)) {
+               free_extent_buffer(right);
                return 1;
        }
-       for (i = left->header.nritems - 1; i >= 0; i--) {
-               item = left->items + i;
+
+       left_nritems = btrfs_header_nritems(left);
+       if (left_nritems == 0) {
+               free_extent_buffer(right);
+               return 1;
+       }
+
+       for (i = left_nritems - 1; i >= 1; i--) {
+               item = btrfs_item_nr(left, i);
                if (path->slots[0] == i)
                        push_space += data_size + sizeof(*item);
-               if (item->size + sizeof(*item) + push_space > free_space)
+               if (btrfs_item_size(left, item) + sizeof(*item) + push_space >
+                   free_space)
                        break;
                push_items++;
-               push_space += item->size + sizeof(*item);
+               push_space += btrfs_item_size(left, item) + sizeof(*item);
        }
+
        if (push_items == 0) {
-               tree_block_release(root, right_buf);
+               free_extent_buffer(right);
                return 1;
        }
+
+       if (push_items == left_nritems)
+               WARN_ON(1);
+
        /* push left to right */
-       push_space = left->items[left->header.nritems - push_items].offset +
-                    left->items[left->header.nritems - push_items].size;
-       push_space -= leaf_data_end(left);
+       right_nritems = btrfs_header_nritems(right);
+       push_space = btrfs_item_end_nr(left, left_nritems - push_items);
+       push_space -= leaf_data_end(root, left);
+
        /* make room in the right data area */
-       memmove(right->data + leaf_data_end(right) - push_space,
-               right->data + leaf_data_end(right),
-               LEAF_DATA_SIZE - leaf_data_end(right));
+       data_end = leaf_data_end(root, right);
+       memmove_extent_buffer(right,
+                             btrfs_leaf_data(right) + data_end - push_space,
+                             btrfs_leaf_data(right) + data_end,
+                             BTRFS_LEAF_DATA_SIZE(root) - data_end);
+
        /* copy from the left data area */
-       memcpy(right->data + LEAF_DATA_SIZE - push_space,
-               left->data + leaf_data_end(left),
-               push_space);
-       memmove(right->items + push_items, right->items,
-               right->header.nritems * sizeof(struct item));
+       copy_extent_buffer(right, left, btrfs_leaf_data(right) +
+                    BTRFS_LEAF_DATA_SIZE(root) - push_space,
+                    btrfs_leaf_data(left) + leaf_data_end(root, left),
+                    push_space);
+
+       memmove_extent_buffer(right, btrfs_item_nr_offset(push_items),
+                             btrfs_item_nr_offset(0),
+                             right_nritems * sizeof(struct btrfs_item));
+
        /* copy the items from left to right */
-       memcpy(right->items, left->items + left->header.nritems - push_items,
-               push_items * sizeof(struct item));
+       copy_extent_buffer(right, left, btrfs_item_nr_offset(0),
+                  btrfs_item_nr_offset(left_nritems - push_items),
+                  push_items * sizeof(struct btrfs_item));
 
        /* update the item pointers */
-       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;
-       }
-       left->header.nritems -= push_items;
-
-       dirty_tree_block(root, left_buf);
-       dirty_tree_block(root, right_buf);
-       memcpy(upper->node.keys + slot + 1,
-               &right->items[0].key, sizeof(struct key));
-       dirty_tree_block(root, upper);
+       right_nritems += push_items;
+       btrfs_set_header_nritems(right, right_nritems);
+       push_space = BTRFS_LEAF_DATA_SIZE(root);
+       for (i = 0; i < right_nritems; i++) {
+               item = btrfs_item_nr(right, i);
+               btrfs_set_item_offset(right, item, push_space -
+                                     btrfs_item_size(right, item));
+               push_space = btrfs_item_offset(right, item);
+       }
+       left_nritems -= push_items;
+       btrfs_set_header_nritems(left, left_nritems);
+
+       btrfs_mark_buffer_dirty(left);
+       btrfs_mark_buffer_dirty(right);
+
+       btrfs_item_key(right, &disk_key, 0);
+       btrfs_set_node_key(upper, &disk_key, slot + 1);
+       btrfs_mark_buffer_dirty(upper);
+
        /* then fixup the leaf pointer in the path */
-       if (path->slots[0] >= left->header.nritems) {
-               path->slots[0] -= left->header.nritems;
-               tree_block_release(root, path->nodes[0]);
-               path->nodes[0] = right_buf;
+       if (path->slots[0] >= left_nritems) {
+               path->slots[0] -= left_nritems;
+               free_extent_buffer(path->nodes[0]);
+               path->nodes[0] = right;
                path->slots[1] += 1;
        } else {
-               tree_block_release(root, right_buf);
+               free_extent_buffer(right);
        }
+       if (path->nodes[1])
+               check_node(root, path, 1);
        return 0;
 }
 /*
  * push some data in the path leaf to the left, trying to free up at
  * least data_size bytes.  returns zero if the push worked, nonzero otherwise
  */
-static int push_leaf_left(struct ctree_root *root, struct ctree_path *path,
-                         int data_size)
+static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
+                         *root, struct btrfs_path *path, int data_size)
 {
-       struct tree_buffer *right_buf = path->nodes[0];
-       struct leaf *right = &right_buf->leaf;
-       struct tree_buffer *t;
-       struct leaf *left;
+       struct btrfs_disk_key disk_key;
+       struct extent_buffer *right = path->nodes[0];
+       struct extent_buffer *left;
        int slot;
        int i;
        int free_space;
        int push_space = 0;
        int push_items = 0;
-       struct item *item;
-       int old_left_nritems;
+       struct btrfs_item *item;
+       u32 old_left_nritems;
+       u32 right_nritems;
        int ret = 0;
        int wret;
 
        slot = path->slots[1];
-       if (slot == 0) {
+       if (slot == 0)
+               return 1;
+       if (!path->nodes[1])
+               return 1;
+
+       left = read_tree_block(root, btrfs_node_blockptr(path->nodes[1],
+                                                        slot - 1));
+       free_space = btrfs_leaf_free_space(root, left);
+       if (free_space < data_size + sizeof(struct btrfs_item)) {
+               free_extent_buffer(left);
                return 1;
        }
-       if (!path->nodes[1]) {
+
+       /* cow and double check */
+       ret = btrfs_cow_block(trans, root, left,
+                             path->nodes[1], slot - 1, &left);
+       if (ret) {
+               /* we hit -ENOSPC, but it isn't fatal here */
+               free_extent_buffer(left);
                return 1;
        }
-       t = read_tree_block(root, path->nodes[1]->node.blockptrs[slot - 1]);
-       left = &t->leaf;
-       free_space = leaf_free_space(left);
-       if (free_space < data_size + sizeof(struct item)) {
-               tree_block_release(root, t);
+       free_space = btrfs_leaf_free_space(root, left);
+       if (free_space < data_size + sizeof(struct btrfs_item)) {
+               free_extent_buffer(left);
+               return 1;
+       }
+
+       right_nritems = btrfs_header_nritems(right);
+       if (right_nritems == 0) {
+               free_extent_buffer(left);
                return 1;
        }
-       for (i = 0; i < right->header.nritems; i++) {
-               item = right->items + i;
+
+       for (i = 0; i < right_nritems - 1; i++) {
+               item = btrfs_item_nr(right, i);
                if (path->slots[0] == i)
                        push_space += data_size + sizeof(*item);
-               if (item->size + sizeof(*item) + push_space > free_space)
+               if (btrfs_item_size(right, item) + sizeof(*item) + push_space >
+                   free_space)
                        break;
                push_items++;
-               push_space += item->size + sizeof(*item);
+               push_space += btrfs_item_size(right, item) + sizeof(*item);
        }
        if (push_items == 0) {
-               tree_block_release(root, t);
+               free_extent_buffer(left);
                return 1;
        }
+       if (push_items == btrfs_header_nritems(right))
+               WARN_ON(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;
+       copy_extent_buffer(left, right,
+                          btrfs_item_nr_offset(btrfs_header_nritems(left)),
+                          btrfs_item_nr_offset(0),
+                          push_items * sizeof(struct btrfs_item));
+
+       push_space = BTRFS_LEAF_DATA_SIZE(root) -
+                    btrfs_item_offset_nr(right, push_items -1);
+
+       copy_extent_buffer(left, right, btrfs_leaf_data(left) +
+                    leaf_data_end(root, left) - push_space,
+                    btrfs_leaf_data(right) +
+                    btrfs_item_offset_nr(right, push_items - 1),
+                    push_space);
+       old_left_nritems = btrfs_header_nritems(left);
        BUG_ON(old_left_nritems < 0);
 
-       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;
+       for (i = old_left_nritems; i < old_left_nritems + push_items; i++) {
+               u32 ioff;
+               item = btrfs_item_nr(left, i);
+               ioff = btrfs_item_offset(left, item);
+               btrfs_set_item_offset(left, item,
+                     ioff - (BTRFS_LEAF_DATA_SIZE(root) -
+                     btrfs_item_offset_nr(left, old_left_nritems - 1)));
        }
-       left->header.nritems += push_items;
+       btrfs_set_header_nritems(left, old_left_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;
+       push_space = btrfs_item_offset_nr(right, push_items - 1) -
+                                         leaf_data_end(root, right);
+       memmove_extent_buffer(right, btrfs_leaf_data(right) +
+                             BTRFS_LEAF_DATA_SIZE(root) - push_space,
+                             btrfs_leaf_data(right) +
+                             leaf_data_end(root, right), push_space);
+
+       memmove_extent_buffer(right, btrfs_item_nr_offset(0),
+                             btrfs_item_nr_offset(push_items),
+                            (btrfs_header_nritems(right) - push_items) *
+                            sizeof(struct btrfs_item));
+
+       right_nritems = btrfs_header_nritems(right) - push_items;
+       btrfs_set_header_nritems(right, right_nritems);
+       push_space = BTRFS_LEAF_DATA_SIZE(root);
+
+       for (i = 0; i < right_nritems; i++) {
+               item = btrfs_item_nr(right, i);
+               btrfs_set_item_offset(right, item, push_space -
+                                     btrfs_item_size(right, item));
+               push_space = btrfs_item_offset(right, item);
        }
 
-       wret = dirty_tree_block(root, t);
-       if (wret)
-               ret = wret;
-       wret = dirty_tree_block(root, right_buf);
-       if (wret)
-               ret = wret;
+       btrfs_mark_buffer_dirty(left);
+       btrfs_mark_buffer_dirty(right);
 
-       wret = fixup_low_keys(root, path, &right->items[0].key, 1);
+       btrfs_item_key(right, &disk_key, 0);
+       wret = fixup_low_keys(trans, root, path, &disk_key, 1);
        if (wret)
                ret = wret;
 
        /* then fixup the leaf pointer in the path */
        if (path->slots[0] < push_items) {
                path->slots[0] += old_left_nritems;
-               tree_block_release(root, path->nodes[0]);
-               path->nodes[0] = t;
+               free_extent_buffer(path->nodes[0]);
+               path->nodes[0] = left;
                path->slots[1] -= 1;
        } else {
-               tree_block_release(root, t);
+               free_extent_buffer(left);
                path->slots[0] -= push_items;
        }
        BUG_ON(path->slots[0] < 0);
+       if (path->nodes[1])
+               check_node(root, path, 1);
        return ret;
 }
 
@@ -943,101 +1669,315 @@ static int push_leaf_left(struct ctree_root *root, struct ctree_path *path,
  *
  * returns 0 if all went well and < 0 on failure.
  */
-static int split_leaf(struct ctree_root *root, struct ctree_path *path,
-                     int data_size)
+static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_key *ins_key,
+                     struct btrfs_path *path, int data_size)
 {
-       struct tree_buffer *l_buf;
-       struct leaf *l;
-       int nritems;
+       struct extent_buffer *l;
+       u32 nritems;
        int mid;
        int slot;
-       struct leaf *right;
-       struct tree_buffer *right_buffer;
-       int space_needed = data_size + sizeof(struct item);
+       struct extent_buffer *right;
+       int space_needed = data_size + sizeof(struct btrfs_item);
        int data_copy_size;
        int rt_data_off;
        int i;
-       int ret;
+       int ret = 0;
        int wret;
+       int double_split = 0;
+       struct btrfs_disk_key disk_key;
 
-       wret = push_leaf_left(root, path, data_size);
+       /* first try to make some room by pushing left and right */
+       wret = push_leaf_left(trans, root, path, data_size);
        if (wret < 0)
                return wret;
        if (wret) {
-               wret = push_leaf_right(root, path, data_size);
+               wret = push_leaf_right(trans, root, path, data_size);
                if (wret < 0)
                        return wret;
        }
-       l_buf = path->nodes[0];
-       l = &l_buf->leaf;
+       l = path->nodes[0];
 
        /* did the pushes work? */
-       if (leaf_free_space(l) >= sizeof(struct item) + data_size)
+       if (btrfs_leaf_free_space(root, l) >=
+           sizeof(struct btrfs_item) + data_size)
                return 0;
 
        if (!path->nodes[1]) {
-               ret = insert_new_root(root, path, 1);
+               ret = insert_new_root(trans, root, path, 1);
                if (ret)
                        return ret;
        }
        slot = path->slots[0];
-       nritems = l->header.nritems;
+       nritems = btrfs_header_nritems(l);
        mid = (nritems + 1)/ 2;
 
-       right_buffer = alloc_free_block(root);
-       BUG_ON(!right_buffer);
-       BUG_ON(mid == nritems);
-       right = &right_buffer->leaf;
-       memset(right, 0, sizeof(*right));
+       right = btrfs_alloc_free_block(trans, root,
+                                             extent_buffer_blocknr(l), 0);
+       if (IS_ERR(right))
+               return PTR_ERR(right);
+
+       memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header));
+       btrfs_set_header_blocknr(right, extent_buffer_blocknr(right));
+       btrfs_set_header_generation(right, trans->transid);
+       btrfs_set_header_owner(right, root->root_key.objectid);
+       btrfs_set_header_level(right, 0);
+       write_extent_buffer(right, root->fs_info->fsid,
+                           (unsigned long)btrfs_header_fsid(right),
+                           BTRFS_FSID_SIZE);
+
        if (mid <= slot) {
-               /* FIXME, just alloc a new leaf here */
-               if (leaf_space_used(l, mid, nritems - mid) + space_needed >
-                       LEAF_DATA_SIZE)
-                       BUG();
+               if (nritems == 1 ||
+                   leaf_space_used(l, mid, nritems - mid) + space_needed >
+                       BTRFS_LEAF_DATA_SIZE(root)) {
+                       if (slot >= nritems) {
+                               btrfs_cpu_key_to_disk(&disk_key, ins_key);
+                               btrfs_set_header_nritems(right, 0);
+                               wret = insert_ptr(trans, root, path,
+                                                 &disk_key,
+                                                 extent_buffer_blocknr(right),
+                                                 path->slots[1] + 1, 1);
+                               if (wret)
+                                       ret = wret;
+                               free_extent_buffer(path->nodes[0]);
+                               path->nodes[0] = right;
+                               path->slots[0] = 0;
+                               path->slots[1] += 1;
+                               return ret;
+                       }
+                       mid = slot;
+                       double_split = 1;
+               }
        } else {
-               /* FIXME, just alloc a new leaf here */
                if (leaf_space_used(l, 0, mid + 1) + space_needed >
-                       LEAF_DATA_SIZE)
-                       BUG();
-       }
-       right->header.nritems = nritems - mid;
-       right->header.blocknr = right_buffer->blocknr;
-       right->header.flags = node_level(0);
-       right->header.parentid = root->node->node.header.parentid;
-       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;
+                       BTRFS_LEAF_DATA_SIZE(root)) {
+                       if (slot == 0) {
+                               btrfs_cpu_key_to_disk(&disk_key, ins_key);
+                               btrfs_set_header_nritems(right, 0);
+                               wret = insert_ptr(trans, root, path,
+                                                 &disk_key,
+                                                 extent_buffer_blocknr(right),
+                                                 path->slots[1], 1);
+                               if (wret)
+                                       ret = wret;
+                               free_extent_buffer(path->nodes[0]);
+                               path->nodes[0] = right;
+                               path->slots[0] = 0;
+                               if (path->slots[1] == 0) {
+                                       wret = fixup_low_keys(trans, root,
+                                                  path, &disk_key, 1);
+                                       if (wret)
+                                               ret = wret;
+                               }
+                               return ret;
+                       }
+                       mid = slot;
+                       double_split = 1;
+               }
+       }
+       nritems = nritems - mid;
+       btrfs_set_header_nritems(right, nritems);
+       data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l);
+
+       copy_extent_buffer(right, l, btrfs_item_nr_offset(0),
+                          btrfs_item_nr_offset(mid),
+                          nritems * sizeof(struct btrfs_item));
+
+       copy_extent_buffer(right, l,
+                    btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) -
+                    data_copy_size, btrfs_leaf_data(l) +
+                    leaf_data_end(root, l), data_copy_size);
+
+       rt_data_off = BTRFS_LEAF_DATA_SIZE(root) -
+                     btrfs_item_end_nr(l, mid);
+
+       for (i = 0; i < nritems; i++) {
+               struct btrfs_item *item = btrfs_item_nr(right, i);
+               u32 ioff = btrfs_item_offset(right, item);
+               btrfs_set_item_offset(right, item, ioff + rt_data_off);
+       }
+
+       btrfs_set_header_nritems(l, mid);
        ret = 0;
-       wret = insert_ptr(root, path, &right->items[0].key,
-                         right_buffer->blocknr, path->slots[1] + 1, 1);
-       if (wret)
-               ret = wret;
-       wret = dirty_tree_block(root, right_buffer);
-       if (wret)
-               ret = wret;
-       wret = dirty_tree_block(root, l_buf);
+       btrfs_item_key(right, &disk_key, 0);
+       wret = insert_ptr(trans, root, path, &disk_key,
+                         extent_buffer_blocknr(right), path->slots[1] + 1, 1);
        if (wret)
                ret = wret;
 
+       btrfs_mark_buffer_dirty(right);
+       btrfs_mark_buffer_dirty(l);
        BUG_ON(path->slots[0] != slot);
+
        if (mid <= slot) {
-               tree_block_release(root, path->nodes[0]);
-               path->nodes[0] = right_buffer;
+               free_extent_buffer(path->nodes[0]);
+               path->nodes[0] = right;
                path->slots[0] -= mid;
                path->slots[1] += 1;
        } else
-               tree_block_release(root, right_buffer);
+               free_extent_buffer(right);
+
        BUG_ON(path->slots[0] < 0);
+       check_node(root, path, 1);
+       check_leaf(root, path, 0);
+
+       if (!double_split)
+               return ret;
+
+       right = btrfs_alloc_free_block(trans, root,
+                                      extent_buffer_blocknr(l), 0);
+       if (IS_ERR(right))
+               return PTR_ERR(right);
+
+       memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header));
+       btrfs_set_header_blocknr(right, extent_buffer_blocknr(right));
+       btrfs_set_header_generation(right, trans->transid);
+       btrfs_set_header_owner(right, root->root_key.objectid);
+       btrfs_set_header_level(right, 0);
+       write_extent_buffer(right, root->fs_info->fsid,
+                           (unsigned long)btrfs_header_fsid(right),
+                           BTRFS_FSID_SIZE);
+
+       btrfs_cpu_key_to_disk(&disk_key, ins_key);
+       btrfs_set_header_nritems(right, 0);
+       wret = insert_ptr(trans, root, path,
+                         &disk_key,
+                         extent_buffer_blocknr(right),
+                         path->slots[1], 1);
+       if (wret)
+               ret = wret;
+       if (path->slots[1] == 0) {
+               wret = fixup_low_keys(trans, root, path, &disk_key, 1);
+               if (wret)
+                       ret = wret;
+       }
+       free_extent_buffer(path->nodes[0]);
+       path->nodes[0] = right;
+       path->slots[0] = 0;
+       check_node(root, path, 1);
+       check_leaf(root, path, 0);
+       return ret;
+}
+
+int btrfs_truncate_item(struct btrfs_trans_handle *trans,
+                       struct btrfs_root *root,
+                       struct btrfs_path *path,
+                       u32 new_size)
+{
+       int ret = 0;
+       int slot;
+       int slot_orig;
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
+       u32 nritems;
+       unsigned int data_end;
+       unsigned int old_data_start;
+       unsigned int old_size;
+       unsigned int size_diff;
+       int i;
+
+       slot_orig = path->slots[0];
+       leaf = path->nodes[0];
+
+       nritems = btrfs_header_nritems(leaf);
+       data_end = leaf_data_end(root, leaf);
+
+       slot = path->slots[0];
+       old_data_start = btrfs_item_offset_nr(leaf, slot);
+       old_size = btrfs_item_size_nr(leaf, slot);
+       BUG_ON(old_size <= new_size);
+       size_diff = old_size - new_size;
+
+       BUG_ON(slot < 0);
+       BUG_ON(slot >= nritems);
+
+       /*
+        * item0..itemN ... dataN.offset..dataN.size .. data0.size
+        */
+       /* first correct the data pointers */
+       for (i = slot; i < nritems; i++) {
+               u32 ioff;
+               item = btrfs_item_nr(leaf, i);
+               ioff = btrfs_item_offset(leaf, item);
+               btrfs_set_item_offset(leaf, item, ioff + size_diff);
+       }
+       /* shift the data */
+       memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                     data_end + size_diff, btrfs_leaf_data(leaf) +
+                     data_end, old_data_start + new_size - data_end);
+
+       item = btrfs_item_nr(leaf, slot);
+       btrfs_set_item_size(leaf, item, new_size);
+       btrfs_mark_buffer_dirty(leaf);
+
+       ret = 0;
+       if (btrfs_leaf_free_space(root, leaf) < 0) {
+               btrfs_print_leaf(root, leaf);
+               BUG();
+       }
+       check_leaf(root, path, 0);
+       return ret;
+}
+
+int btrfs_extend_item(struct btrfs_trans_handle *trans,
+                     struct btrfs_root *root, struct btrfs_path *path,
+                     u32 data_size)
+{
+       int ret = 0;
+       int slot;
+       int slot_orig;
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
+       u32 nritems;
+       unsigned int data_end;
+       unsigned int old_data;
+       unsigned int old_size;
+       int i;
+
+       slot_orig = path->slots[0];
+       leaf = path->nodes[0];
+
+       nritems = btrfs_header_nritems(leaf);
+       data_end = leaf_data_end(root, leaf);
+
+       if (btrfs_leaf_free_space(root, leaf) < data_size) {
+               btrfs_print_leaf(root, leaf);
+               BUG();
+       }
+       slot = path->slots[0];
+       old_data = btrfs_item_end_nr(leaf, slot);
+
+       BUG_ON(slot < 0);
+       BUG_ON(slot >= nritems);
+
+       /*
+        * item0..itemN ... dataN.offset..dataN.size .. data0.size
+        */
+       /* first correct the data pointers */
+       for (i = slot; i < nritems; i++) {
+               u32 ioff;
+               item = btrfs_item_nr(leaf, i);
+               ioff = btrfs_item_offset(leaf, item);
+               btrfs_set_item_offset(leaf, item, ioff - data_size);
+       }
+
+       /* shift the data */
+       memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                     data_end - data_size, btrfs_leaf_data(leaf) +
+                     data_end, old_data - data_end);
+
+       data_end = old_data;
+       old_size = btrfs_item_size_nr(leaf, slot);
+       item = btrfs_item_nr(leaf, slot);
+       btrfs_set_item_size(leaf, item, old_size + data_size);
+       btrfs_mark_buffer_dirty(leaf);
+
+       ret = 0;
+       if (btrfs_leaf_free_space(root, leaf) < 0) {
+               btrfs_print_leaf(root, leaf);
+               BUG();
+       }
+       check_leaf(root, path, 0);
        return ret;
 }
 
@@ -1045,84 +1985,124 @@ static int split_leaf(struct ctree_root *root, struct ctree_path *path,
  * Given a key and some data, insert an item into the tree.
  * This does all the path init required, making room in the tree if needed.
  */
-int insert_item(struct ctree_root *root, struct key *key,
-                         void *data, int data_size)
+int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
+                           struct btrfs_path *path,
+                           struct btrfs_key *cpu_key, u32 data_size)
 {
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
        int ret = 0;
-       int wret;
        int slot;
        int slot_orig;
-       struct leaf *leaf;
-       struct tree_buffer *leaf_buf;
-       unsigned int nritems;
+       u32 nritems;
        unsigned int data_end;
-       struct ctree_path path;
+       struct btrfs_disk_key disk_key;
+
+       btrfs_cpu_key_to_disk(&disk_key, cpu_key);
 
        /* create a root if there isn't one */
        if (!root->node)
                BUG();
-       init_path(&path);
-       ret = search_slot(root, key, &path, data_size);
+
+       ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1);
        if (ret == 0) {
-               release_path(root, &path);
                return -EEXIST;
        }
        if (ret < 0)
                goto out;
 
-       slot_orig = path.slots[0];
-       leaf_buf = path.nodes[0];
-       leaf = &leaf_buf->leaf;
+       slot_orig = path->slots[0];
+       leaf = path->nodes[0];
 
-       nritems = leaf->header.nritems;
-       data_end = leaf_data_end(leaf);
+       nritems = btrfs_header_nritems(leaf);
+       data_end = leaf_data_end(root, leaf);
 
-       if (leaf_free_space(leaf) <  sizeof(struct item) + data_size)
+       if (btrfs_leaf_free_space(root, leaf) <
+           sizeof(struct btrfs_item) + data_size) {
                BUG();
+       }
 
-       slot = path.slots[0];
+       slot = path->slots[0];
        BUG_ON(slot < 0);
+
        if (slot != nritems) {
                int i;
-               unsigned int old_data = leaf->items[slot].offset +
-                                       leaf->items[slot].size;
+               unsigned int old_data = btrfs_item_end_nr(leaf, slot);
 
+               if (old_data < data_end) {
+                       btrfs_print_leaf(root, leaf);
+                       printk("slot %d old_data %d data_end %d\n",
+                              slot, old_data, data_end);
+                       BUG_ON(1);
+               }
                /*
                 * 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;
+               for (i = slot; i < nritems; i++) {
+                       u32 ioff;
+                       item = btrfs_item_nr(leaf, i);
+                       ioff = btrfs_item_offset(leaf, item);
+                       btrfs_set_item_offset(leaf, item, ioff - data_size);
+               }
 
                /* shift the items */
-               memmove(leaf->items + slot + 1, leaf->items + slot,
-                       (nritems - slot) * sizeof(struct item));
+               memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1),
+                             btrfs_item_nr_offset(slot),
+                             (nritems - slot) * sizeof(struct btrfs_item));
 
                /* shift the data */
-               memmove(leaf->data + data_end - data_size, leaf->data +
-                       data_end, old_data - data_end);
+               memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                             data_end - data_size, btrfs_leaf_data(leaf) +
+                             data_end, old_data - data_end);
                data_end = old_data;
        }
-       /* copy the new data in */
-       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;
+
+       /* setup the item for the new data */
+       btrfs_set_item_key(leaf, &disk_key, slot);
+       item = btrfs_item_nr(leaf, slot);
+       btrfs_set_item_offset(leaf, item, data_end - data_size);
+       btrfs_set_item_size(leaf, item, data_size);
+       btrfs_set_header_nritems(leaf, nritems + 1);
+       btrfs_mark_buffer_dirty(leaf);
 
        ret = 0;
        if (slot == 0)
-               ret = fixup_low_keys(root, &path, key, 1);
-
-       wret = dirty_tree_block(root, leaf_buf);
-       if (wret)
-               ret = wret;
+               ret = fixup_low_keys(trans, root, path, &disk_key, 1);
 
-       if (leaf_free_space(leaf) < 0)
+       if (btrfs_leaf_free_space(root, leaf) < 0) {
+               btrfs_print_leaf(root, leaf);
                BUG();
-       check_leaf(&path, 0);
+       }
+       check_leaf(root, path, 0);
 out:
-       release_path(root, &path);
+       return ret;
+}
+
+/*
+ * Given a key and some data, insert an item into the tree.
+ * This does all the path init required, making room in the tree if needed.
+ */
+int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
+                     *root, struct btrfs_key *cpu_key, void *data, u32
+                     data_size)
+{
+       int ret = 0;
+       struct btrfs_path *path;
+       struct extent_buffer *leaf;
+       unsigned long ptr;
+
+       path = btrfs_alloc_path();
+       BUG_ON(!path);
+       ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
+       if (!ret) {
+               leaf = path->nodes[0];
+               ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+               write_extent_buffer(leaf, data, ptr, data_size);
+               btrfs_mark_buffer_dirty(leaf);
+       }
+       btrfs_free_path(path);
        return ret;
 }
 
@@ -1133,38 +2113,37 @@ out:
  * continuing all the way the root if required.  The root is converted into
  * a leaf if all the nodes are emptied.
  */
-static int del_ptr(struct ctree_root *root, struct ctree_path *path, int level,
-                  int slot)
+static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+                  struct btrfs_path *path, int level, int slot)
 {
-       struct node *node;
-       struct tree_buffer *parent = path->nodes[level];
-       int nritems;
+       struct extent_buffer *parent = path->nodes[level];
+       u32 nritems;
        int ret = 0;
        int wret;
 
-       node = &parent->node;
-       nritems = node->header.nritems;
-
+       nritems = btrfs_header_nritems(parent);
        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 && parent == root->node) {
-               BUG_ON(node_level(root->node->node.header.flags) != 1);
+               memmove_extent_buffer(parent,
+                             btrfs_node_key_ptr_offset(slot),
+                             btrfs_node_key_ptr_offset(slot + 1),
+                             sizeof(struct btrfs_key_ptr) *
+                             (nritems - slot - 1));
+       }
+       nritems--;
+       btrfs_set_header_nritems(parent, nritems);
+       if (nritems == 0 && parent == root->node) {
+               BUG_ON(btrfs_header_level(root->node) != 1);
                /* just turn the root into a leaf and break */
-               root->node->node.header.flags = node_level(0);
+               btrfs_set_header_level(root->node, 0);
        } else if (slot == 0) {
-               wret = fixup_low_keys(root, path, node->keys, level + 1);
+               struct btrfs_disk_key disk_key;
+
+               btrfs_node_key(parent, &disk_key, 0);
+               wret = fixup_low_keys(trans, root, path, &disk_key, level + 1);
                if (wret)
                        ret = wret;
        }
-       wret = dirty_tree_block(root, parent);
-       if (wret)
-               ret = wret;
+       btrfs_mark_buffer_dirty(parent);
        return ret;
 }
 
@@ -1172,91 +2151,116 @@ static int del_ptr(struct ctree_root *root, struct ctree_path *path, int level,
  * delete the item at the leaf level in path.  If that empties
  * the leaf, remove it from the tree
  */
-int del_item(struct ctree_root *root, struct ctree_path *path)
+int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+                  struct btrfs_path *path)
 {
        int slot;
-       struct leaf *leaf;
-       struct tree_buffer *leaf_buf;
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
        int doff;
        int dsize;
        int ret = 0;
        int wret;
+       u32 nritems;
 
-       leaf_buf = path->nodes[0];
-       leaf = &leaf_buf->leaf;
+       leaf = path->nodes[0];
        slot = path->slots[0];
-       doff = leaf->items[slot].offset;
-       dsize = leaf->items[slot].size;
+       doff = btrfs_item_offset_nr(leaf, slot);
+       dsize = btrfs_item_size_nr(leaf, slot);
+       nritems = btrfs_header_nritems(leaf);
 
-       if (slot != leaf->header.nritems - 1) {
+       if (slot != 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;
+               int data_end = leaf_data_end(root, leaf);
+
+               memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                             data_end + dsize,
+                             btrfs_leaf_data(leaf) + data_end,
+                             doff - data_end);
+
+               for (i = slot + 1; i < nritems; i++) {
+                       u32 ioff;
+                       item = btrfs_item_nr(leaf, i);
+                       ioff = btrfs_item_offset(leaf, item);
+                       btrfs_set_item_offset(leaf, item, ioff + dsize);
+               }
+               memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot),
+                             btrfs_item_nr_offset(slot + 1),
+                             sizeof(struct btrfs_item) *
+                             (nritems - slot - 1));
+       }
+       btrfs_set_header_nritems(leaf, nritems - 1);
+       nritems--;
+
        /* delete the leaf if we've emptied it */
-       if (leaf->header.nritems == 0) {
-               if (leaf_buf == root->node) {
-                       leaf->header.flags = node_level(0);
-                       dirty_tree_block(root, leaf_buf);
+       if (nritems == 0) {
+               if (leaf == root->node) {
+                       btrfs_set_header_level(leaf, 0);
                } else {
-                       clean_tree_block(root, leaf_buf);
-                       wret = del_ptr(root, path, 1, path->slots[1]);
+                       clean_tree_block(trans, root, leaf);
+                       wait_on_tree_block_writeback(root, leaf);
+                       wret = del_ptr(trans, root, path, 1, path->slots[1]);
                        if (wret)
                                ret = wret;
-                       wret = free_extent(root, leaf_buf->blocknr, 1);
+                       wret = btrfs_free_extent(trans, root,
+                                                extent_buffer_blocknr(leaf),
+                                                1, 1);
                        if (wret)
                                ret = wret;
                }
        } else {
-               int used = leaf_space_used(leaf, 0, leaf->header.nritems);
+               int used = leaf_space_used(leaf, 0, nritems);
                if (slot == 0) {
-                       wret = fixup_low_keys(root, path,
-                                                  &leaf->items[0].key, 1);
+                       struct btrfs_disk_key disk_key;
+
+                       btrfs_item_key(leaf, &disk_key, 0);
+                       wret = fixup_low_keys(trans, root, path,
+                                             &disk_key, 1);
                        if (wret)
                                ret = wret;
                }
-               wret = dirty_tree_block(root, leaf_buf);
-               if (wret)
-                       ret = wret;
 
                /* delete the leaf if it is mostly empty */
-               if (used < LEAF_DATA_SIZE / 3) {
+               if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) {
                        /* 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];
-                       leaf_buf->count++;
-                       wret = push_leaf_left(root, path, 1);
-                       if (wret < 0)
+                       extent_buffer_get(leaf);
+
+                       wret = push_leaf_left(trans, root, path, 1);
+                       if (wret < 0 && wret != -ENOSPC)
                                ret = wret;
-                       if (path->nodes[0] == leaf_buf &&
-                           leaf->header.nritems) {
-                               wret = push_leaf_right(root, path, 1);
-                               if (wret < 0)
+
+                       if (path->nodes[0] == leaf &&
+                           btrfs_header_nritems(leaf)) {
+                               wret = push_leaf_right(trans, root, path, 1);
+                               if (wret < 0 && wret != -ENOSPC)
                                        ret = wret;
                        }
-                       if (leaf->header.nritems == 0) {
-                               u64 blocknr = leaf_buf->blocknr;
-                               clean_tree_block(root, leaf_buf);
-                               wret = del_ptr(root, path, 1, slot);
+
+                       if (btrfs_header_nritems(leaf) == 0) {
+                               u64 blocknr = extent_buffer_blocknr(leaf);
+
+                               clean_tree_block(trans, root, leaf);
+                               wait_on_tree_block_writeback(root, leaf);
+
+                               wret = del_ptr(trans, root, path, 1, slot);
                                if (wret)
                                        ret = wret;
-                               tree_block_release(root, leaf_buf);
-                               wret = free_extent(root, blocknr, 1);
+
+                               free_extent_buffer(leaf);
+                               wret = btrfs_free_extent(trans, root, blocknr,
+                                                        1, 1);
                                if (wret)
                                        ret = wret;
                        } else {
-                               tree_block_release(root, leaf_buf);
+                               btrfs_mark_buffer_dirty(leaf);
+                               free_extent_buffer(leaf);
                        }
+               } else {
+                       btrfs_mark_buffer_dirty(leaf);
                }
        }
        return ret;
@@ -1267,26 +2271,32 @@ int del_item(struct ctree_root *root, struct ctree_path *path)
  * returns 0 if it found something or 1 if there are no greater leaves.
  * returns < 0 on io errors.
  */
-int next_leaf(struct ctree_root *root, struct ctree_path *path)
+int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
        int slot;
        int level = 1;
        u64 blocknr;
-       struct tree_buffer *c;
-       struct tree_buffer *next = NULL;
+       struct extent_buffer *c;
+       struct extent_buffer *next = NULL;
 
-       while(level < MAX_LEVEL) {
+       while(level < BTRFS_MAX_LEVEL) {
                if (!path->nodes[level])
                        return 1;
+
                slot = path->slots[level] + 1;
                c = path->nodes[level];
-               if (slot >= c->node.header.nritems) {
+               if (slot >= btrfs_header_nritems(c)) {
                        level++;
                        continue;
                }
-               blocknr = c->node.blockptrs[slot];
+
+               blocknr = btrfs_node_blockptr(c, slot);
                if (next)
-                       tree_block_release(root, next);
+                       free_extent_buffer(next);
+
+               if (path->reada)
+                       reada_for_search(root, path, level, slot);
+
                next = read_tree_block(root, blocknr);
                break;
        }
@@ -1294,13 +2304,14 @@ int next_leaf(struct ctree_root *root, struct ctree_path *path)
        while(1) {
                level--;
                c = path->nodes[level];
-               tree_block_release(root, c);
+               free_extent_buffer(c);
                path->nodes[level] = next;
                path->slots[level] = 0;
                if (!level)
                        break;
-               next = read_tree_block(root, next->node.blockptrs[0]);
+               if (path->reada)
+                       reada_for_search(root, path, level, 0);
+               next = read_tree_block(root, btrfs_node_blockptr(next, 0));
        }
        return 0;
 }
-