libbtrfsutil: fix test assumptions about top-level subvolume
[platform/upstream/btrfs-progs.git] / ctree.c
diff --git a/ctree.c b/ctree.c
index 0c85b0b..e26a1c2 100644 (file)
--- a/ctree.c
+++ b/ctree.c
-#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 "ctree.h"
 #include "disk-io.h"
+#include "transaction.h"
 #include "print-tree.h"
+#include "repair.h"
+#include "internal.h"
+#include "sizes.h"
+#include "messages.h"
 
 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_path *path, int data_size);
-static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root
-                         *root, struct btrfs_buffer *dst, struct btrfs_buffer
-                         *src);
-static int balance_node_right(struct btrfs_trans_handle *trans, struct
-                             btrfs_root *root, struct btrfs_buffer *dst_buf,
-                             struct btrfs_buffer *src_buf);
-static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                  struct btrfs_path *path, int level, int slot);
+                     *root, struct btrfs_key *ins_key,
+                     struct btrfs_path *path, int data_size, int extend);
+static int push_node_left(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root, struct extent_buffer *dst,
+                         struct extent_buffer *src, int empty);
+static int balance_node_right(struct btrfs_trans_handle *trans,
+                             struct btrfs_root *root,
+                             struct extent_buffer *dst_buf,
+                             struct extent_buffer *src_buf);
 
 inline void btrfs_init_path(struct btrfs_path *p)
 {
        memset(p, 0, sizeof(*p));
 }
 
-void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p)
+struct btrfs_path *btrfs_alloc_path(void)
+{
+       struct btrfs_path *path;
+       path = kzalloc(sizeof(struct btrfs_path), GFP_NOFS);
+       return path;
+}
+
+void btrfs_free_path(struct btrfs_path *p)
+{
+       if (!p)
+               return;
+       btrfs_release_path(p);
+       kfree(p);
+}
+
+void btrfs_release_path(struct btrfs_path *p)
 {
        int i;
        for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
                if (!p->nodes[i])
-                       break;
-               btrfs_block_release(root, p->nodes[i]);
+                       continue;
+               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 btrfs_buffer *buf, struct btrfs_buffer
-                          *parent, int parent_slot, struct btrfs_buffer
-                          **cow_ret)
+void add_root_to_dirty_list(struct btrfs_root *root)
 {
-       struct btrfs_buffer *cow;
+       if (root->track_dirty && list_empty(&root->dirty_list)) {
+               list_add(&root->dirty_list,
+                        &root->fs_info->dirty_cowonly_roots);
+       }
+}
 
-       if (!list_empty(&buf->dirty)) {
-               *cow_ret = buf;
-               return 0;
+int btrfs_copy_root(struct btrfs_trans_handle *trans,
+                     struct btrfs_root *root,
+                     struct extent_buffer *buf,
+                     struct extent_buffer **cow_ret, u64 new_root_objectid)
+{
+       struct extent_buffer *cow;
+       int ret = 0;
+       int level;
+       struct btrfs_root *new_root;
+       struct btrfs_disk_key disk_key;
+
+       new_root = kmalloc(sizeof(*new_root), GFP_NOFS);
+       if (!new_root)
+               return -ENOMEM;
+
+       memcpy(new_root, root, sizeof(*new_root));
+       new_root->root_key.objectid = new_root_objectid;
+
+       WARN_ON(root->ref_cows && trans->transid !=
+               root->fs_info->running_transaction->transid);
+       WARN_ON(root->ref_cows && trans->transid != root->last_trans);
+
+       level = btrfs_header_level(buf);
+       if (level == 0)
+               btrfs_item_key(buf, &disk_key, 0);
+       else
+               btrfs_node_key(buf, &disk_key, 0);
+       cow = btrfs_alloc_free_block(trans, new_root, buf->len,
+                                    new_root_objectid, &disk_key,
+                                    level, buf->start, 0);
+       if (IS_ERR(cow)) {
+               kfree(new_root);
+               return PTR_ERR(cow);
        }
-       cow = btrfs_alloc_free_block(trans, root);
-       memcpy(&cow->node, &buf->node, root->blocksize);
-       btrfs_set_header_blocknr(&cow->node.header, cow->blocknr);
-       btrfs_set_header_owner(&cow->node.header, root->root_key.objectid);
+
+       copy_extent_buffer(cow, buf, 0, 0, cow->len);
+       btrfs_set_header_bytenr(cow, cow->start);
+       btrfs_set_header_generation(cow, trans->transid);
+       btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
+       btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN |
+                                    BTRFS_HEADER_FLAG_RELOC);
+       if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID)
+               btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC);
+       else
+               btrfs_set_header_owner(cow, new_root_objectid);
+
+       write_extent_buffer(cow, root->fs_info->fsid,
+                           btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+       WARN_ON(btrfs_header_generation(buf) > trans->transid);
+       ret = btrfs_inc_ref(trans, new_root, cow, 0);
+       kfree(new_root);
+
+       if (ret)
+               return ret;
+
+       btrfs_mark_buffer_dirty(cow);
        *cow_ret = cow;
-       btrfs_inc_ref(trans, root, buf);
-       if (buf == root->node) {
-               root->node = cow;
-               cow->count++;
-               if (buf != root->commit_root)
-                       btrfs_free_extent(trans, root, buf->blocknr, 1, 1);
-               btrfs_block_release(root, buf);
-       } else {
-               btrfs_set_node_blockptr(&parent->node, parent_slot,
-                                       cow->blocknr);
-               BUG_ON(list_empty(&parent->dirty));
-               btrfs_free_extent(trans, root, buf->blocknr, 1, 1);
-       }
-       btrfs_block_release(root, buf);
        return 0;
 }
 
 /*
- * 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
+ * check if the tree block can be shared by multiple trees
  */
-static inline unsigned int leaf_data_end(struct btrfs_root *root,
-                                        struct btrfs_leaf *leaf)
+static int btrfs_block_can_be_shared(struct btrfs_root *root,
+                                    struct extent_buffer *buf)
 {
-       u32 nr = btrfs_header_nritems(&leaf->header);
-       if (nr == 0)
-               return BTRFS_LEAF_DATA_SIZE(root);
-       return btrfs_item_offset(leaf->items + nr - 1);
+       /*
+        * Tree blocks not in reference counted trees and tree roots
+        * are never shared. If a block was allocated after the last
+        * snapshot and the block was not allocated by tree relocation,
+        * we know the block is not shared.
+        */
+       if (root->ref_cows &&
+           buf != root->node && buf != root->commit_root &&
+           (btrfs_header_generation(buf) <=
+            btrfs_root_last_snapshot(&root->root_item) ||
+            btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)))
+               return 1;
+#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
+        if (root->ref_cows &&
+            btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
+                return 1;
+#endif
+       return 0;
 }
 
-/*
- * 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 btrfs_leaf *leaf)
+static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans,
+                                      struct btrfs_root *root,
+                                      struct extent_buffer *buf,
+                                      struct extent_buffer *cow)
+{
+       u64 refs;
+       u64 owner;
+       u64 flags;
+       u64 new_flags = 0;
+       int ret;
+
+       /*
+        * Backrefs update rules:
+        *
+        * Always use full backrefs for extent pointers in tree block
+        * allocated by tree relocation.
+        *
+        * If a shared tree block is no longer referenced by its owner
+        * tree (btrfs_header_owner(buf) == root->root_key.objectid),
+        * use full backrefs for extent pointers in tree block.
+        *
+        * If a tree block is been relocating
+        * (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID),
+        * use full backrefs for extent pointers in tree block.
+        * The reason for this is some operations (such as drop tree)
+        * are only allowed for blocks use full backrefs.
+        */
+
+       if (btrfs_block_can_be_shared(root, buf)) {
+               ret = btrfs_lookup_extent_info(trans, root, buf->start,
+                                              btrfs_header_level(buf), 1,
+                                              &refs, &flags);
+               BUG_ON(ret);
+               BUG_ON(refs == 0);
+       } else {
+               refs = 1;
+               if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID ||
+                   btrfs_header_backref_rev(buf) < BTRFS_MIXED_BACKREF_REV)
+                       flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
+               else
+                       flags = 0;
+       }
+
+       owner = btrfs_header_owner(buf);
+       BUG_ON(!(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) &&
+              owner == BTRFS_TREE_RELOC_OBJECTID);
+
+       if (refs > 1) {
+               if ((owner == root->root_key.objectid ||
+                    root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) &&
+                   !(flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) {
+                       ret = btrfs_inc_ref(trans, root, buf, 1);
+                       BUG_ON(ret);
+
+                       if (root->root_key.objectid ==
+                           BTRFS_TREE_RELOC_OBJECTID) {
+                               ret = btrfs_dec_ref(trans, root, buf, 0);
+                               BUG_ON(ret);
+                               ret = btrfs_inc_ref(trans, root, cow, 1);
+                               BUG_ON(ret);
+                       }
+                       new_flags |= BTRFS_BLOCK_FLAG_FULL_BACKREF;
+               } else {
+
+                       if (root->root_key.objectid ==
+                           BTRFS_TREE_RELOC_OBJECTID)
+                               ret = btrfs_inc_ref(trans, root, cow, 1);
+                       else
+                               ret = btrfs_inc_ref(trans, root, cow, 0);
+                       BUG_ON(ret);
+               }
+               if (new_flags != 0) {
+                       ret = btrfs_set_block_flags(trans, root, buf->start,
+                                                   btrfs_header_level(buf),
+                                                   new_flags);
+                       BUG_ON(ret);
+               }
+       } else {
+               if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) {
+                       if (root->root_key.objectid ==
+                           BTRFS_TREE_RELOC_OBJECTID)
+                               ret = btrfs_inc_ref(trans, root, cow, 1);
+                       else
+                               ret = btrfs_inc_ref(trans, root, cow, 0);
+                       BUG_ON(ret);
+                       ret = btrfs_dec_ref(trans, root, buf, 1);
+                       BUG_ON(ret);
+               }
+               clean_tree_block(trans, root, buf);
+       }
+       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, u64 empty_size)
 {
-       int data_end = leaf_data_end(root, leaf);
-       int nritems = btrfs_header_nritems(&leaf->header);
-       char *items_end = (char *)(leaf->items + nritems + 1);
-       return (char *)(btrfs_leaf_data(leaf) + data_end) - (char *)items_end;
+       struct extent_buffer *cow;
+       struct btrfs_disk_key disk_key;
+       int level;
+
+       WARN_ON(root->ref_cows && trans->transid !=
+               root->fs_info->running_transaction->transid);
+       WARN_ON(root->ref_cows && trans->transid != root->last_trans);
+
+       level = btrfs_header_level(buf);
+
+       if (level == 0)
+               btrfs_item_key(buf, &disk_key, 0);
+       else
+               btrfs_node_key(buf, &disk_key, 0);
+
+       cow = btrfs_alloc_free_block(trans, root, buf->len,
+                                    root->root_key.objectid, &disk_key,
+                                    level, search_start, empty_size);
+       if (IS_ERR(cow))
+               return PTR_ERR(cow);
+
+       copy_extent_buffer(cow, buf, 0, 0, cow->len);
+       btrfs_set_header_bytenr(cow, cow->start);
+       btrfs_set_header_generation(cow, trans->transid);
+       btrfs_set_header_backref_rev(cow, BTRFS_MIXED_BACKREF_REV);
+       btrfs_clear_header_flag(cow, BTRFS_HEADER_FLAG_WRITTEN |
+                                    BTRFS_HEADER_FLAG_RELOC);
+       if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
+               btrfs_set_header_flag(cow, BTRFS_HEADER_FLAG_RELOC);
+       else
+               btrfs_set_header_owner(cow, root->root_key.objectid);
+
+       write_extent_buffer(cow, root->fs_info->fsid,
+                           btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+       WARN_ON(!(buf->flags & EXTENT_BAD_TRANSID) &&
+               btrfs_header_generation(buf) > trans->transid);
+
+       update_ref_for_cow(trans, root, buf, cow);
+
+       if (buf == root->node) {
+               root->node = cow;
+               extent_buffer_get(cow);
+
+               btrfs_free_extent(trans, root, buf->start, buf->len,
+                                 0, root->root_key.objectid, level, 0);
+               free_extent_buffer(buf);
+               add_root_to_dirty_list(root);
+       } else {
+               btrfs_set_node_blockptr(parent, parent_slot,
+                                       cow->start);
+               WARN_ON(trans->transid == 0);
+               btrfs_set_node_ptr_generation(parent, parent_slot,
+                                             trans->transid);
+               btrfs_mark_buffer_dirty(parent);
+               WARN_ON(btrfs_header_generation(parent) != trans->transid);
+
+               btrfs_free_extent(trans, root, buf->start, buf->len,
+                                 0, root->root_key.objectid, level, 1);
+       }
+       if (!list_empty(&buf->recow)) {
+               list_del_init(&buf->recow);
+               free_extent_buffer(buf);
+       }
+       free_extent_buffer(buf);
+       btrfs_mark_buffer_dirty(cow);
+       *cow_ret = cow;
+       return 0;
 }
 
-/*
- * compare two keys in a memcmp fashion
- */
-static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
+static inline int should_cow_block(struct btrfs_trans_handle *trans,
+                                  struct btrfs_root *root,
+                                  struct extent_buffer *buf)
 {
-       struct btrfs_key k1;
+       if (btrfs_header_generation(buf) == trans->transid &&
+           !btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN) &&
+           !(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID &&
+             btrfs_header_flag(buf, BTRFS_HEADER_FLAG_RELOC)))
+               return 0;
+       return 1;
+}
 
-       btrfs_disk_key_to_cpu(&k1, disk);
+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;
+       int ret;
+       /*
+       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 %llu running %llu\n",
+                       (unsigned long long)trans->transid,
+                       (unsigned long long)root->fs_info->generation);
+               WARN_ON(1);
+       }
+       if (!should_cow_block(trans, root, buf)) {
+               *cow_ret = buf;
+               return 0;
+       }
+
+       search_start = buf->start & ~((u64)SZ_1G - 1);
+       ret = __btrfs_cow_block(trans, root, buf, parent,
+                                parent_slot, cow_ret, search_start, 0);
+       return ret;
+}
 
-       if (k1.objectid > k2->objectid)
+int btrfs_comp_cpu_keys(struct btrfs_key *k1, struct btrfs_key *k2)
+{
+       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;
 }
 
-static int check_node(struct btrfs_root *root, struct btrfs_path *path,
-                     int level)
+/*
+ * compare two keys in a memcmp fashion
+ */
+static int btrfs_comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
+{
+       struct btrfs_key k1;
+
+       btrfs_disk_key_to_cpu(&k1, disk);
+       return btrfs_comp_cpu_keys(&k1, k2);
+}
+
+/*
+ * 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(const struct btrfs_fs_info *fs_info,
+                                        const struct extent_buffer *leaf)
+{
+       u32 nr = btrfs_header_nritems(leaf);
+       if (nr == 0)
+               return BTRFS_LEAF_DATA_SIZE(fs_info);
+       return btrfs_item_offset_nr(leaf, nr - 1);
+}
+
+enum btrfs_tree_block_status
+btrfs_check_node(struct btrfs_root *root, struct btrfs_disk_key *parent_key,
+                struct extent_buffer *buf)
 {
        int i;
-       struct btrfs_node *parent = NULL;
-       struct btrfs_node *node = &path->nodes[level]->node;
-       int parent_slot;
-       u32 nritems = btrfs_header_nritems(&node->header);
-
-       if (path->nodes[level + 1])
-               parent = &path->nodes[level + 1]->node;
-       parent_slot = path->slots[level + 1];
-       BUG_ON(nritems == 0);
-       if (parent) {
-               struct btrfs_disk_key *parent_key;
-               parent_key = &parent->ptrs[parent_slot].key;
-               BUG_ON(memcmp(parent_key, &node->ptrs[0].key,
-                             sizeof(struct btrfs_disk_key)));
-               BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
-                      btrfs_header_blocknr(&node->header));
-       }
-       BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root));
+       struct btrfs_key cpukey;
+       struct btrfs_disk_key key;
+       u32 nritems = btrfs_header_nritems(buf);
+       enum btrfs_tree_block_status ret = BTRFS_TREE_BLOCK_INVALID_NRITEMS;
+
+       if (nritems == 0 || nritems > BTRFS_NODEPTRS_PER_BLOCK(root->fs_info))
+               goto fail;
+
+       ret = BTRFS_TREE_BLOCK_INVALID_PARENT_KEY;
+       if (parent_key && parent_key->type) {
+               btrfs_node_key(buf, &key, 0);
+               if (memcmp(parent_key, &key, sizeof(key)))
+                       goto fail;
+       }
+       ret = BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
        for (i = 0; nritems > 1 && i < nritems - 2; i++) {
-               struct btrfs_key cpukey;
-               btrfs_disk_key_to_cpu(&cpukey, &node->ptrs[i + 1].key);
-               BUG_ON(comp_keys(&node->ptrs[i].key, &cpukey) >= 0);
+               btrfs_node_key(buf, &key, i);
+               btrfs_node_key_to_cpu(buf, &cpukey, i + 1);
+               if (btrfs_comp_keys(&key, &cpukey) >= 0)
+                       goto fail;
        }
-       return 0;
+       return BTRFS_TREE_BLOCK_CLEAN;
+fail:
+       if (btrfs_header_owner(buf) == BTRFS_EXTENT_TREE_OBJECTID) {
+               if (parent_key)
+                       btrfs_disk_key_to_cpu(&cpukey, parent_key);
+               else
+                       btrfs_node_key_to_cpu(buf, &cpukey, 0);
+               btrfs_add_corrupt_extent_record(root->fs_info, &cpukey,
+                                               buf->start, buf->len,
+                                               btrfs_header_level(buf));
+       }
+       return ret;
 }
 
-static int check_leaf(struct btrfs_root *root, struct btrfs_path *path,
-                     int level)
+enum btrfs_tree_block_status
+btrfs_check_leaf(struct btrfs_root *root, struct btrfs_disk_key *parent_key,
+                struct extent_buffer *buf)
 {
        int i;
-       struct btrfs_leaf *leaf = &path->nodes[level]->leaf;
-       struct btrfs_node *parent = NULL;
-       int parent_slot;
-       u32 nritems = btrfs_header_nritems(&leaf->header);
+       struct btrfs_key cpukey;
+       struct btrfs_disk_key key;
+       u32 nritems = btrfs_header_nritems(buf);
+       enum btrfs_tree_block_status ret = BTRFS_TREE_BLOCK_INVALID_NRITEMS;
+
+       if (nritems * sizeof(struct btrfs_item) > buf->len)  {
+               fprintf(stderr, "invalid number of items %llu\n",
+                       (unsigned long long)buf->start);
+               goto fail;
+       }
 
-       if (path->nodes[level + 1])
-               parent = &path->nodes[level + 1]->node;
-       parent_slot = path->slots[level + 1];
-       BUG_ON(btrfs_leaf_free_space(root, leaf) < 0);
+       if (btrfs_header_level(buf) != 0) {
+               ret = BTRFS_TREE_BLOCK_INVALID_LEVEL;
+               fprintf(stderr, "leaf is not a leaf %llu\n",
+                      (unsigned long long)btrfs_header_bytenr(buf));
+               goto fail;
+       }
+       if (btrfs_leaf_free_space(root, buf) < 0) {
+               ret = BTRFS_TREE_BLOCK_INVALID_FREE_SPACE;
+               fprintf(stderr, "leaf free space incorrect %llu %d\n",
+                       (unsigned long long)btrfs_header_bytenr(buf),
+                       btrfs_leaf_free_space(root, buf));
+               goto fail;
+       }
 
        if (nritems == 0)
-               return 0;
-
-       if (parent) {
-               struct btrfs_disk_key *parent_key;
-               parent_key = &parent->ptrs[parent_slot].key;
-               BUG_ON(memcmp(parent_key, &leaf->items[0].key,
-                      sizeof(struct btrfs_disk_key)));
-               BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
-                      btrfs_header_blocknr(&leaf->header));
+               return BTRFS_TREE_BLOCK_CLEAN;
+
+       btrfs_item_key(buf, &key, 0);
+       if (parent_key && parent_key->type &&
+           memcmp(parent_key, &key, sizeof(key))) {
+               ret = BTRFS_TREE_BLOCK_INVALID_PARENT_KEY;
+               fprintf(stderr, "leaf parent key incorrect %llu\n",
+                      (unsigned long long)btrfs_header_bytenr(buf));
+               goto fail;
        }
-       for (i = 0; nritems > 1 && i < nritems - 2; i++) {
-               struct btrfs_key cpukey;
-               btrfs_disk_key_to_cpu(&cpukey, &leaf->items[i + 1].key);
-               BUG_ON(comp_keys(&leaf->items[i].key,
-                                &cpukey) >= 0);
-               BUG_ON(btrfs_item_offset(leaf->items + i) !=
-                       btrfs_item_end(leaf->items + i + 1));
-               if (i == 0) {
-                       BUG_ON(btrfs_item_offset(leaf->items + i) +
-                              btrfs_item_size(leaf->items + i) !=
-                              BTRFS_LEAF_DATA_SIZE(root));
+       for (i = 0; nritems > 1 && i < nritems - 1; i++) {
+               btrfs_item_key(buf, &key, i);
+               btrfs_item_key_to_cpu(buf, &cpukey, i + 1);
+               if (btrfs_comp_keys(&key, &cpukey) >= 0) {
+                       ret = BTRFS_TREE_BLOCK_BAD_KEY_ORDER;
+                       fprintf(stderr, "bad key ordering %d %d\n", i, i+1);
+                       goto fail;
+               }
+               if (btrfs_item_offset_nr(buf, i) !=
+                       btrfs_item_end_nr(buf, i + 1)) {
+                       ret = BTRFS_TREE_BLOCK_INVALID_OFFSETS;
+                       fprintf(stderr, "incorrect offsets %u %u\n",
+                               btrfs_item_offset_nr(buf, i),
+                               btrfs_item_end_nr(buf, i + 1));
+                       goto fail;
+               }
+               if (i == 0 && btrfs_item_end_nr(buf, i) !=
+                   BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+                       ret = BTRFS_TREE_BLOCK_INVALID_OFFSETS;
+                       fprintf(stderr, "bad item end %u wanted %u\n",
+                               btrfs_item_end_nr(buf, i),
+                               (unsigned)BTRFS_LEAF_DATA_SIZE(root->fs_info));
+                       goto fail;
                }
        }
-       return 0;
+
+       for (i = 0; i < nritems; i++) {
+               if (btrfs_item_end_nr(buf, i) >
+                               BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+                       btrfs_item_key(buf, &key, 0);
+                       btrfs_print_key(&key);
+                       fflush(stdout);
+                       ret = BTRFS_TREE_BLOCK_INVALID_OFFSETS;
+                       fprintf(stderr, "slot end outside of leaf %llu > %llu\n",
+                               (unsigned long long)btrfs_item_end_nr(buf, i),
+                               (unsigned long long)BTRFS_LEAF_DATA_SIZE(
+                                       root->fs_info));
+                       goto fail;
+               }
+       }
+
+       return BTRFS_TREE_BLOCK_CLEAN;
+fail:
+       if (btrfs_header_owner(buf) == BTRFS_EXTENT_TREE_OBJECTID) {
+               if (parent_key)
+                       btrfs_disk_key_to_cpu(&cpukey, parent_key);
+               else
+                       btrfs_item_key_to_cpu(buf, &cpukey, 0);
+
+               btrfs_add_corrupt_extent_record(root->fs_info, &cpukey,
+                                               buf->start, buf->len, 0);
+       }
+       return ret;
 }
 
-static int check_block(struct btrfs_root *root, struct btrfs_path *path,
-                       int level)
+static int noinline check_block(struct btrfs_root *root,
+                               struct btrfs_path *path, int level)
 {
+       struct btrfs_disk_key key;
+       struct btrfs_disk_key *key_ptr = NULL;
+       struct extent_buffer *parent;
+       enum btrfs_tree_block_status ret;
+
+       if (path->skip_check_block)
+               return 0;
+       if (path->nodes[level + 1]) {
+               parent = path->nodes[level + 1];
+               btrfs_node_key(parent, &key, path->slots[level + 1]);
+               key_ptr = &key;
+       }
        if (level == 0)
-               return check_leaf(root, path, level);
-       return check_node(root, path, level);
+               ret =  btrfs_check_leaf(root, key_ptr, path->nodes[0]);
+       else
+               ret = btrfs_check_node(root, key_ptr, path->nodes[level]);
+       if (ret == BTRFS_TREE_BLOCK_CLEAN)
+               return 0;
+       return -EIO;
 }
 
 /*
- * 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
  */
-static int generic_bin_search(char *p, int item_size, struct btrfs_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;
+       unsigned long offset;
        struct btrfs_disk_key *tmp;
 
        while(low < high) {
                mid = (low + high) / 2;
-               tmp = (struct btrfs_disk_key *)(p + mid * item_size);
-               ret = comp_keys(tmp, key);
+               offset = p + mid * item_size;
+
+               tmp = (struct btrfs_disk_key *)(eb->data + offset);
+               ret = btrfs_comp_keys(tmp, key);
 
                if (ret < 0)
                        low = mid + 1;
@@ -238,46 +623,62 @@ static int generic_bin_search(char *p, int item_size, struct btrfs_key *key,
  * simple bin_search frontend that does the right thing for
  * leaves vs nodes
  */
-static int bin_search(struct btrfs_node *c, struct btrfs_key *key, int *slot)
+static int bin_search(struct extent_buffer *eb, struct btrfs_key *key,
+                     int level, int *slot)
 {
-       if (btrfs_is_leaf(c)) {
-               struct btrfs_leaf *l = (struct btrfs_leaf *)c;
-               return generic_bin_search((void *)l->items,
+       if (level == 0)
+               return generic_bin_search(eb,
+                                         offsetof(struct btrfs_leaf, items),
                                          sizeof(struct btrfs_item),
-                                         key, btrfs_header_nritems(&c->header),
+                                         key, btrfs_header_nritems(eb),
                                          slot);
-       } else {
-               return generic_bin_search((void *)c->ptrs,
+       else
+               return generic_bin_search(eb,
+                                         offsetof(struct btrfs_node, ptrs),
                                          sizeof(struct btrfs_key_ptr),
-                                         key, btrfs_header_nritems(&c->header),
+                                         key, btrfs_header_nritems(eb),
                                          slot);
-       }
-       return -1;
 }
 
-static struct btrfs_buffer *read_node_slot(struct btrfs_root *root,
-                                  struct btrfs_buffer *parent_buf,
-                                  int slot)
+struct extent_buffer *read_node_slot(struct btrfs_fs_info *fs_info,
+                                  struct extent_buffer *parent, int slot)
 {
-       struct btrfs_node *node = &parent_buf->node;
+       struct extent_buffer *ret;
+       int level = btrfs_header_level(parent);
+
        if (slot < 0)
                return NULL;
-       if (slot >= btrfs_header_nritems(&node->header))
+       if (slot >= btrfs_header_nritems(parent))
                return NULL;
-       return read_tree_block(root, btrfs_node_blockptr(node, slot));
+
+       if (level == 0)
+               return NULL;
+
+       ret = read_tree_block(fs_info, btrfs_node_blockptr(parent, slot),
+                      btrfs_node_ptr_generation(parent, slot));
+       if (!extent_buffer_uptodate(ret))
+               return ERR_PTR(-EIO);
+
+       if (btrfs_header_level(ret) != level - 1) {
+               error(
+"child eb corrupted: parent bytenr=%llu item=%d parent level=%d child level=%d",
+                     btrfs_header_bytenr(parent), slot,
+                     btrfs_header_level(parent), btrfs_header_level(ret));
+               free_extent_buffer(ret);
+               return ERR_PTR(-EIO);
+       }
+       return ret;
 }
 
-static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root
-                        *root, struct btrfs_path *path, int level)
+static int balance_level(struct btrfs_trans_handle *trans,
+                        struct btrfs_root *root,
+                        struct btrfs_path *path, int level)
 {
-       struct btrfs_buffer *right_buf;
-       struct btrfs_buffer *mid_buf;
-       struct btrfs_buffer *left_buf;
-       struct btrfs_buffer *parent_buf = NULL;
-       struct btrfs_node *right = NULL;
-       struct btrfs_node *mid;
-       struct btrfs_node *left = NULL;
-       struct btrfs_node *parent = NULL;
+       struct extent_buffer *right = NULL;
+       struct extent_buffer *mid;
+       struct extent_buffer *left = NULL;
+       struct extent_buffer *parent = NULL;
+       struct btrfs_fs_info *fs_info = root->fs_info;
        int ret = 0;
        int wret;
        int pslot;
@@ -287,53 +688,73 @@ static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root
        if (level == 0)
                return 0;
 
-       mid_buf = path->nodes[level];
-       mid = &mid_buf->node;
+       mid = path->nodes[level];
+       WARN_ON(btrfs_header_generation(mid) != trans->transid);
+
        orig_ptr = btrfs_node_blockptr(mid, orig_slot);
 
-       if (level < BTRFS_MAX_LEVEL - 1)
-               parent_buf = path->nodes[level + 1];
-       pslot = path->slots[level + 1];
+       if (level < BTRFS_MAX_LEVEL - 1) {
+               parent = path->nodes[level + 1];
+               pslot = path->slots[level + 1];
+       }
 
        /*
         * deal with the case where there is only one pointer in the root
         * by promoting the node below to a root
         */
-       if (!parent_buf) {
-               struct btrfs_buffer *child;
-               u64 blocknr = mid_buf->blocknr;
+       if (!parent) {
+               struct extent_buffer *child;
 
-               if (btrfs_header_nritems(&mid->header) != 1)
+               if (btrfs_header_nritems(mid) != 1)
                        return 0;
 
                /* promote the child to a root */
-               child = read_node_slot(root, mid_buf, 0);
-               BUG_ON(!child);
+               child = read_node_slot(fs_info, mid, 0);
+               BUG_ON(!extent_buffer_uptodate(child));
+               ret = btrfs_cow_block(trans, root, child, mid, 0, &child);
+               BUG_ON(ret);
+
                root->node = child;
+               add_root_to_dirty_list(root);
                path->nodes[level] = NULL;
+               clean_tree_block(trans, root, mid);
                /* once for the path */
-               btrfs_block_release(root, mid_buf);
+               free_extent_buffer(mid);
+
+               ret = btrfs_free_extent(trans, root, mid->start, mid->len,
+                                       0, root->root_key.objectid,
+                                       level, 1);
                /* once for the root ptr */
-               btrfs_block_release(root, mid_buf);
-               clean_tree_block(trans, root, mid_buf);
-               return btrfs_free_extent(trans, root, blocknr, 1, 1);
+               free_extent_buffer(mid);
+               return ret;
        }
-       parent = &parent_buf->node;
-
-       if (btrfs_header_nritems(&mid->header) >
-           BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
+       if (btrfs_header_nritems(mid) >
+           BTRFS_NODEPTRS_PER_BLOCK(fs_info) / 4)
                return 0;
 
-       left_buf = read_node_slot(root, parent_buf, pslot - 1);
-       right_buf = read_node_slot(root, parent_buf, pslot + 1);
+       left = read_node_slot(fs_info, parent, pslot - 1);
+       if (extent_buffer_uptodate(left)) {
+               wret = btrfs_cow_block(trans, root, left,
+                                      parent, pslot - 1, &left);
+               if (wret) {
+                       ret = wret;
+                       goto enospc;
+               }
+       }
+       right = read_node_slot(fs_info, parent, pslot + 1);
+       if (extent_buffer_uptodate(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) {
-               btrfs_cow_block(trans, root, left_buf, parent_buf, pslot - 1,
-                               &left_buf);
-               left = &left_buf->node;
-               orig_slot += btrfs_header_nritems(&left->header);
-               wret = push_node_left(trans, root, left_buf, mid_buf);
+       if (left) {
+               orig_slot += btrfs_header_nritems(left);
+               wret = push_node_left(trans, root, left, mid, 1);
                if (wret < 0)
                        ret = wret;
        }
@@ -341,34 +762,34 @@ static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root
        /*
         * then try to empty the right most buffer into the middle
         */
-       if (right_buf) {
-               btrfs_cow_block(trans, root, right_buf, parent_buf, pslot + 1,
-                               &right_buf);
-               right = &right_buf->node;
-               wret = push_node_left(trans, root, mid_buf, right_buf);
-               if (wret < 0)
+       if (right) {
+               wret = push_node_left(trans, root, mid, right, 1);
+               if (wret < 0 && wret != -ENOSPC)
                        ret = wret;
-               if (btrfs_header_nritems(&right->header) == 0) {
-                       u64 blocknr = right_buf->blocknr;
-                       btrfs_block_release(root, right_buf);
-                       clean_tree_block(trans, root, right_buf);
-                       right_buf = NULL;
+               if (btrfs_header_nritems(right) == 0) {
+                       u64 bytenr = right->start;
+                       u32 blocksize = right->len;
+
+                       clean_tree_block(trans, root, right);
+                       free_extent_buffer(right);
                        right = NULL;
-                       wret = del_ptr(trans, root, path, level + 1, pslot +
-                                      1);
+                       wret = btrfs_del_ptr(root, path, level + 1, pslot + 1);
                        if (wret)
                                ret = wret;
-                       wret = btrfs_free_extent(trans, root, blocknr, 1, 1);
+                       wret = btrfs_free_extent(trans, root, bytenr,
+                                                blocksize, 0,
+                                                root->root_key.objectid,
+                                                level, 0);
                        if (wret)
                                ret = wret;
                } else {
-                       memcpy(&parent->ptrs[pslot + 1].key,
-                               &right->ptrs[0].key,
-                               sizeof(struct btrfs_disk_key));
-                       BUG_ON(list_empty(&parent_buf->dirty));
+                       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 (btrfs_header_nritems(&mid->header) == 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
@@ -378,174 +799,492 @@ static int balance_level(struct btrfs_trans_handle *trans, struct btrfs_root
                 * otherwise we would have pulled some pointers from the
                 * right
                 */
-               BUG_ON(!left_buf);
-               wret = balance_node_right(trans, 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;
+               }
+               if (wret == 1) {
+                       wret = push_node_left(trans, root, left, mid, 1);
+                       if (wret < 0)
+                               ret = wret;
+               }
                BUG_ON(wret == 1);
        }
-       if (btrfs_header_nritems(&mid->header) == 0) {
+       if (btrfs_header_nritems(mid) == 0) {
                /* we've managed to empty the middle node, drop it */
-               u64 blocknr = mid_buf->blocknr;
-               btrfs_block_release(root, mid_buf);
-               clean_tree_block(trans, root, mid_buf);
-               mid_buf = NULL;
+               u64 bytenr = mid->start;
+               u32 blocksize = mid->len;
+               clean_tree_block(trans, root, mid);
+               free_extent_buffer(mid);
                mid = NULL;
-               wret = del_ptr(trans, root, path, level + 1, pslot);
+               wret = btrfs_del_ptr(root, path, level + 1, pslot);
                if (wret)
                        ret = wret;
-               wret = btrfs_free_extent(trans, root, blocknr, 1, 1);
+               wret = btrfs_free_extent(trans, root, bytenr, blocksize,
+                                        0, root->root_key.objectid,
+                                        level, 0);
                if (wret)
                        ret = wret;
        } else {
                /* update the parent key to reflect our changes */
-               memcpy(&parent->ptrs[pslot].key, &mid->ptrs[0].key,
-                      sizeof(struct btrfs_disk_key));
-               BUG_ON(list_empty(&parent_buf->dirty));
+               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 (btrfs_header_nritems(&left->header) > 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)
-                               btrfs_block_release(root, mid_buf);
+                       if (mid)
+                               free_extent_buffer(mid);
                } else {
-                       orig_slot -= btrfs_header_nritems(&left->header);
+                       orig_slot -= btrfs_header_nritems(left);
                        path->slots[level] = orig_slot;
                }
        }
        /* double check we haven't messed things up */
        check_block(root, path, level);
-       if (orig_ptr != btrfs_node_blockptr(&path->nodes[level]->node,
-                                           path->slots[level]))
+       if (orig_ptr !=
+           btrfs_node_blockptr(path->nodes[level], path->slots[level]))
                BUG();
-
-       if (right_buf)
-               btrfs_block_release(root, right_buf);
-       if (left_buf)
-               btrfs_block_release(root, left_buf);
+enospc:
+       if (right)
+               free_extent_buffer(right);
+       if (left)
+               free_extent_buffer(left);
        return ret;
 }
 
-/*
- * 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
- * level of the path (level 0)
- *
- * If the key isn't found, the path points to the slot where it should
- * be inserted, and 1 is returned.  If there are other errors during the
- * search a negative error number is returned.
- *
- * if ins_len > 0, nodes and leaves will be split as we walk down the
- * tree.  if ins_len < 0, nodes will be merged as we walk down the tree (if
- * possible)
- */
-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)
+/* returns zero if the push worked, non-zero otherwise */
+static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
+                                         struct btrfs_root *root,
+                                         struct btrfs_path *path, int level)
 {
-       struct btrfs_buffer *b;
-       struct btrfs_buffer *cow_buf;
-       struct btrfs_node *c;
-       int slot;
-       int ret;
-       int level;
+       struct extent_buffer *right = NULL;
+       struct extent_buffer *mid;
+       struct extent_buffer *left = NULL;
+       struct extent_buffer *parent = NULL;
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       int ret = 0;
+       int wret;
+       int pslot;
+       int orig_slot = path->slots[level];
 
-again:
-       b = root->node;
-       b->count++;
-       while (b) {
-               level = btrfs_header_level(&b->node.header);
-               if (cow) {
-                       int wret;
-                       wret = btrfs_cow_block(trans, root, b, p->nodes[level +
-                                              1], p->slots[level + 1],
-                                              &cow_buf);
-                       b = cow_buf;
-               }
-               BUG_ON(!cow && ins_len);
-               c = &b->node;
-               p->nodes[level] = b;
-               ret = check_block(root, p, level);
-               if (ret)
-                       return -1;
-               ret = bin_search(c, key, &slot);
-               if (!btrfs_is_leaf(c)) {
-                       if (ret && slot > 0)
-                               slot -= 1;
-                       p->slots[level] = slot;
-                       if (ins_len > 0 && btrfs_header_nritems(&c->header) ==
-                           BTRFS_NODEPTRS_PER_BLOCK(root)) {
-                               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(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(btrfs_header_nritems(&c->header) == 1);
-                       }
-                       b = read_tree_block(root, btrfs_node_blockptr(c, slot));
+       if (level == 0)
+               return 1;
+
+       mid = path->nodes[level];
+       WARN_ON(btrfs_header_generation(mid) != trans->transid);
+
+       if (level < BTRFS_MAX_LEVEL - 1) {
+               parent = path->nodes[level + 1];
+               pslot = path->slots[level + 1];
+       }
+
+       if (!parent)
+               return 1;
+
+       left = read_node_slot(fs_info, parent, pslot - 1);
+
+       /* first, try to make some room in the middle buffer */
+       if (extent_buffer_uptodate(left)) {
+               u32 left_nr;
+               left_nr = btrfs_header_nritems(left);
+               if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 1) {
+                       wret = 1;
                } else {
-                       struct btrfs_leaf *l = (struct btrfs_leaf *)c;
-                       p->slots[level] = slot;
-                       if (ins_len > 0 && btrfs_leaf_free_space(root, l) <
-                           sizeof(struct btrfs_item) + ins_len) {
-                               int sret = split_leaf(trans, root, p, ins_len);
-                               BUG_ON(sret > 0);
-                               if (sret)
-                                       return sret;
+                       ret = btrfs_cow_block(trans, root, left, parent,
+                                             pslot - 1, &left);
+                       if (ret)
+                               wret = 1;
+                       else {
+                               wret = push_node_left(trans, root,
+                                                     left, mid, 0);
                        }
-                       BUG_ON(root->node->count == 1);
-                       return ret;
                }
-       }
-       BUG_ON(root->node->count == 1);
-       return 1;
-}
-
+               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);
+                       }
+                       return 0;
+               }
+               free_extent_buffer(left);
+       }
+       right= read_node_slot(fs_info, parent, pslot + 1);
+
+       /*
+        * then try to empty the right most buffer into the middle
+        */
+       if (extent_buffer_uptodate(right)) {
+               u32 right_nr;
+               right_nr = btrfs_header_nritems(right);
+               if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - 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);
+                       }
+                       return 0;
+               }
+               free_extent_buffer(right);
+       }
+       return 1;
+}
+
+/*
+ * readahead one full node of leaves
+ */
+void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
+                            int level, int slot, u64 objectid)
+{
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       struct extent_buffer *node;
+       struct btrfs_disk_key disk_key;
+       u32 nritems;
+       u64 search;
+       u64 lowest_read;
+       u64 highest_read;
+       u64 nread = 0;
+       int direction = path->reada;
+       struct extent_buffer *eb;
+       u32 nr;
+       u32 nscan = 0;
+
+       if (level != 1)
+               return;
+
+       if (!path->nodes[level])
+               return;
+
+       node = path->nodes[level];
+       search = btrfs_node_blockptr(node, slot);
+       eb = btrfs_find_tree_block(fs_info, search, fs_info->nodesize);
+       if (eb) {
+               free_extent_buffer(eb);
+               return;
+       }
+
+       highest_read = search;
+       lowest_read = search;
+
+       nritems = btrfs_header_nritems(node);
+       nr = slot;
+       while(1) {
+               if (direction < 0) {
+                       if (nr == 0)
+                               break;
+                       nr--;
+               } else if (direction > 0) {
+                       nr++;
+                       if (nr >= nritems)
+                               break;
+               }
+               if (path->reada < 0 && objectid) {
+                       btrfs_node_key(node, &disk_key, nr);
+                       if (btrfs_disk_key_objectid(&disk_key) != objectid)
+                               break;
+               }
+               search = btrfs_node_blockptr(node, nr);
+               if ((search >= lowest_read && search <= highest_read) ||
+                   (search < lowest_read && lowest_read - search <= 32768) ||
+                   (search > highest_read && search - highest_read <= 32768)) {
+                       readahead_tree_block(fs_info, search,
+                                    btrfs_node_ptr_generation(node, nr));
+                       nread += fs_info->nodesize;
+               }
+               nscan++;
+               if (path->reada < 2 && (nread > SZ_256K || nscan > 32))
+                       break;
+               if(nread > SZ_1M || nscan > 128)
+                       break;
+
+               if (search < lowest_read)
+                       lowest_read = search;
+               if (search > highest_read)
+                       highest_read = search;
+       }
+}
+
+int btrfs_find_item(struct btrfs_root *fs_root, struct btrfs_path *found_path,
+               u64 iobjectid, u64 ioff, u8 key_type,
+               struct btrfs_key *found_key)
+{
+       int ret;
+       struct btrfs_key key;
+       struct extent_buffer *eb;
+       struct btrfs_path *path;
+
+       key.type = key_type;
+       key.objectid = iobjectid;
+       key.offset = ioff;
+
+       if (found_path == NULL) {
+               path = btrfs_alloc_path();
+               if (!path)
+                       return -ENOMEM;
+       } else
+               path = found_path;
+
+       ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
+       if ((ret < 0) || (found_key == NULL))
+               goto out;
+
+       eb = path->nodes[0];
+       if (ret && path->slots[0] >= btrfs_header_nritems(eb)) {
+               ret = btrfs_next_leaf(fs_root, path);
+               if (ret)
+                       goto out;
+               eb = path->nodes[0];
+       }
+
+       btrfs_item_key_to_cpu(eb, found_key, path->slots[0]);
+       if (found_key->type != key.type ||
+                       found_key->objectid != key.objectid) {
+               ret = 1;
+               goto out;
+       }
+
+out:
+       if (path != found_path)
+               btrfs_free_path(path);
+       return ret;
+}
+
+/*
+ * 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
+ * level of the path (level 0)
+ *
+ * If the key isn't found, the path points to the slot where it should
+ * be inserted, and 1 is returned.  If there are other errors during the
+ * search a negative error number is returned.
+ *
+ * if ins_len > 0, nodes and leaves will be split as we walk down the
+ * tree.  if ins_len < 0, nodes will be merged as we walk down the tree (if
+ * possible)
+ */
+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 extent_buffer *b;
+       int slot;
+       int ret;
+       int level;
+       int should_reada = p->reada;
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       u8 lowest_level = 0;
+
+       lowest_level = p->lowest_level;
+       WARN_ON(lowest_level && ins_len > 0);
+       WARN_ON(p->nodes[0] != NULL);
+       /*
+       WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
+       */
+again:
+       b = root->node;
+       extent_buffer_get(b);
+       while (b) {
+               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(root, p, level);
+               if (ret)
+                       return -1;
+               ret = bin_search(b, key, level, &slot);
+               if (level != 0) {
+                       if (ret && slot > 0)
+                               slot -= 1;
+                       p->slots[level] = slot;
+                       if ((p->search_for_split || ins_len > 0) &&
+                           btrfs_header_nritems(b) >=
+                           BTRFS_NODEPTRS_PER_BLOCK(fs_info) - 3) {
+                               int sret = split_node(trans, root, p, level);
+                               BUG_ON(sret > 0);
+                               if (sret)
+                                       return sret;
+                               b = p->nodes[level];
+                               slot = p->slots[level];
+                       } else if (ins_len < 0) {
+                               int sret = balance_level(trans, root, p,
+                                                        level);
+                               if (sret)
+                                       return sret;
+                               b = p->nodes[level];
+                               if (!b) {
+                                       btrfs_release_path(p);
+                                       goto again;
+                               }
+                               slot = p->slots[level];
+                               BUG_ON(btrfs_header_nritems(b) == 1);
+                       }
+                       /* this is only true while dropping a snapshot */
+                       if (level == lowest_level)
+                               break;
+
+                       if (should_reada)
+                               reada_for_search(root, p, level, slot,
+                                                key->objectid);
+
+                       b = read_node_slot(fs_info, b, slot);
+                       if (!extent_buffer_uptodate(b))
+                               return -EIO;
+               } else {
+                       p->slots[level] = slot;
+                       if (ins_len > 0 &&
+                           ins_len > btrfs_leaf_free_space(root, b)) {
+                               int sret = split_leaf(trans, root, key,
+                                                     p, ins_len, ret == 0);
+                               BUG_ON(sret > 0);
+                               if (sret)
+                                       return sret;
+                       }
+                       return ret;
+               }
+       }
+       return 1;
+}
+
 /*
  * adjust the pointers going up the tree, starting at level
  * making sure the right key of each node is points to 'key'.
  * This is used after shifting pointers to the left, so it stops
  * fixing up pointers when a given leaf/node is not in slot 0 of the
  * higher levels
- *
- * 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 btrfs_trans_handle *trans, struct btrfs_root
-                         *root, struct btrfs_path *path, struct btrfs_disk_key
-                         *key, int level)
+void btrfs_fixup_low_keys(struct btrfs_root *root, struct btrfs_path *path,
+                         struct btrfs_disk_key *key, int level)
 {
        int i;
-       int ret = 0;
+       struct extent_buffer *t;
+
        for (i = level; i < BTRFS_MAX_LEVEL; i++) {
-               struct btrfs_node *t;
                int tslot = path->slots[i];
                if (!path->nodes[i])
                        break;
-               t = &path->nodes[i]->node;
-               memcpy(&t->ptrs[tslot].key, key, sizeof(*key));
-               BUG_ON(list_empty(&path->nodes[i]->dirty));
+               t = path->nodes[i];
+               btrfs_set_node_key(t, key, tslot);
+               btrfs_mark_buffer_dirty(path->nodes[i]);
                if (tslot != 0)
                        break;
        }
-       return ret;
+}
+
+/*
+ * update item key.
+ *
+ * This function isn't completely safe. It's the caller's responsibility
+ * that the new key won't break the order
+ */
+int btrfs_set_item_key_safe(struct btrfs_root *root, struct btrfs_path *path,
+                           struct btrfs_key *new_key)
+{
+       struct btrfs_disk_key disk_key;
+       struct extent_buffer *eb;
+       int slot;
+
+       eb = path->nodes[0];
+       slot = path->slots[0];
+       if (slot > 0) {
+               btrfs_item_key(eb, &disk_key, slot - 1);
+               if (btrfs_comp_keys(&disk_key, new_key) >= 0)
+                       return -1;
+       }
+       if (slot < btrfs_header_nritems(eb) - 1) {
+               btrfs_item_key(eb, &disk_key, slot + 1);
+               if (btrfs_comp_keys(&disk_key, new_key) <= 0)
+                       return -1;
+       }
+
+       btrfs_cpu_key_to_disk(&disk_key, new_key);
+       btrfs_set_item_key(eb, &disk_key, slot);
+       btrfs_mark_buffer_dirty(eb);
+       if (slot == 0)
+               btrfs_fixup_low_keys(root, path, &disk_key, 1);
+       return 0;
+}
+
+/*
+ * update an item key without the safety checks.  This is meant to be called by
+ * fsck only.
+ */
+void btrfs_set_item_key_unsafe(struct btrfs_root *root,
+                              struct btrfs_path *path,
+                              struct btrfs_key *new_key)
+{
+       struct btrfs_disk_key disk_key;
+       struct extent_buffer *eb;
+       int slot;
+
+       eb = path->nodes[0];
+       slot = path->slots[0];
+
+       btrfs_cpu_key_to_disk(&disk_key, new_key);
+       btrfs_set_item_key(eb, &disk_key, slot);
+       btrfs_mark_buffer_dirty(eb);
+       if (slot == 0)
+               btrfs_fixup_low_keys(root, path, &disk_key, 1);
 }
 
 /*
@@ -555,38 +1294,59 @@ static int fixup_low_keys(struct btrfs_trans_handle *trans, struct btrfs_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 btrfs_trans_handle *trans, struct btrfs_root
-                         *root, struct btrfs_buffer *dst_buf, struct
-                         btrfs_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, int empty)
 {
-       struct btrfs_node *src = &src_buf->node;
-       struct btrfs_node *dst = &dst_buf->node;
        int push_items = 0;
        int src_nritems;
        int dst_nritems;
        int ret = 0;
 
-       src_nritems = btrfs_header_nritems(&src->header);
-       dst_nritems = btrfs_header_nritems(&dst->header);
-       push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems;
+       src_nritems = btrfs_header_nritems(src);
+       dst_nritems = btrfs_header_nritems(dst);
+       push_items = BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - dst_nritems;
+       WARN_ON(btrfs_header_generation(src) != trans->transid);
+       WARN_ON(btrfs_header_generation(dst) != trans->transid);
+
+       if (!empty && src_nritems <= 8)
+               return 1;
+
        if (push_items <= 0) {
                return 1;
        }
 
-       if (src_nritems < push_items)
-               push_items = src_nritems;
+       if (empty) {
+               push_items = min(src_nritems, push_items);
+               if (push_items < src_nritems) {
+                       /* leave at least 8 pointers in the node if
+                        * we aren't going to empty it
+                        */
+                       if (src_nritems - push_items < 8) {
+                               if (push_items <= 8)
+                                       return 1;
+                               push_items -= 8;
+                       }
+               }
+       } else
+               push_items = min(src_nritems - 8, push_items);
+
+       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));
 
-       memcpy(dst->ptrs + dst_nritems, src->ptrs,
-               push_items * sizeof(struct btrfs_key_ptr));
        if (push_items < src_nritems) {
-               memmove(src->ptrs, src->ptrs + push_items,
-                       (src_nritems - push_items) *
-                       sizeof(struct btrfs_key_ptr));
-       }
-       btrfs_set_header_nritems(&src->header, src_nritems - push_items);
-       btrfs_set_header_nritems(&dst->header, dst_nritems + push_items);
-       BUG_ON(list_empty(&src_buf->dirty));
-       BUG_ON(list_empty(&dst_buf->dirty));
+               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));
+       }
+       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;
 }
 
@@ -599,42 +1359,56 @@ static int push_node_left(struct btrfs_trans_handle *trans, struct btrfs_root
  *
  * this will  only push up to 1/2 the contents of the left node over
  */
-static int balance_node_right(struct btrfs_trans_handle *trans, struct
-                             btrfs_root *root, struct btrfs_buffer *dst_buf,
-                             struct btrfs_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 btrfs_node *src = &src_buf->node;
-       struct btrfs_node *dst = &dst_buf->node;
        int push_items = 0;
        int max_push;
        int src_nritems;
        int dst_nritems;
        int ret = 0;
 
-       src_nritems = btrfs_header_nritems(&src->header);
-       dst_nritems = btrfs_header_nritems(&dst->header);
-       push_items = BTRFS_NODEPTRS_PER_BLOCK(root) - dst_nritems;
+       WARN_ON(btrfs_header_generation(src) != trans->transid);
+       WARN_ON(btrfs_header_generation(dst) != trans->transid);
+
+       src_nritems = btrfs_header_nritems(src);
+       dst_nritems = btrfs_header_nritems(dst);
+       push_items = BTRFS_NODEPTRS_PER_BLOCK(root->fs_info) - dst_nritems;
        if (push_items <= 0) {
                return 1;
        }
 
+       if (src_nritems < 4) {
+               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->ptrs + push_items, dst->ptrs,
-               dst_nritems * sizeof(struct btrfs_key_ptr));
-       memcpy(dst->ptrs, src->ptrs + src_nritems - push_items,
-               push_items * sizeof(struct btrfs_key_ptr));
+       memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items),
+                                     btrfs_node_key_ptr_offset(0),
+                                     (dst_nritems) *
+                                     sizeof(struct btrfs_key_ptr));
 
-       btrfs_set_header_nritems(&src->header, src_nritems - push_items);
-       btrfs_set_header_nritems(&dst->header, dst_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));
+
+       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);
 
-       BUG_ON(list_empty(&src_buf->dirty));
-       BUG_ON(list_empty(&dst_buf->dirty));
        return ret;
 }
 
@@ -645,36 +1419,65 @@ static int balance_node_right(struct btrfs_trans_handle *trans, struct
  *
  * returns zero on success or < 0 on failure.
  */
-static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root
-                          *root, struct btrfs_path *path, int level)
+static int noinline insert_new_root(struct btrfs_trans_handle *trans,
+                          struct btrfs_root *root,
+                          struct btrfs_path *path, int level)
 {
-       struct btrfs_buffer *t;
-       struct btrfs_node *lower;
-       struct btrfs_node *c;
-       struct btrfs_disk_key *lower_key;
+       u64 lower_gen;
+       struct extent_buffer *lower;
+       struct extent_buffer *c;
+       struct extent_buffer *old;
+       struct btrfs_disk_key lower_key;
 
        BUG_ON(path->nodes[level]);
        BUG_ON(path->nodes[level-1] != root->node);
 
-       t = btrfs_alloc_free_block(trans, root);
-       c = &t->node;
-       memset(c, 0, root->blocksize);
-       btrfs_set_header_nritems(&c->header, 1);
-       btrfs_set_header_level(&c->header, level);
-       btrfs_set_header_blocknr(&c->header, t->blocknr);
-       btrfs_set_header_owner(&c->header, root->root_key.objectid);
-       lower = &path->nodes[level-1]->node;
-       if (btrfs_is_leaf(lower))
-               lower_key = &((struct btrfs_leaf *)lower)->items[0].key;
+       lower = path->nodes[level-1];
+       if (level == 1)
+               btrfs_item_key(lower, &lower_key, 0);
        else
-               lower_key = &lower->ptrs[0].key;
-       memcpy(&c->ptrs[0].key, lower_key, sizeof(struct btrfs_disk_key));
-       btrfs_set_node_blockptr(c, 0, path->nodes[level - 1]->blocknr);
+               btrfs_node_key(lower, &lower_key, 0);
+
+       c = btrfs_alloc_free_block(trans, root, root->fs_info->nodesize,
+                                  root->root_key.objectid, &lower_key, 
+                                  level, root->node->start, 0);
+
+       if (IS_ERR(c))
+               return PTR_ERR(c);
+
+       memset_extent_buffer(c, 0, 0, sizeof(struct btrfs_header));
+       btrfs_set_header_nritems(c, 1);
+       btrfs_set_header_level(c, level);
+       btrfs_set_header_bytenr(c, c->start);
+       btrfs_set_header_generation(c, trans->transid);
+       btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV);
+       btrfs_set_header_owner(c, root->root_key.objectid);
+
+       write_extent_buffer(c, root->fs_info->fsid,
+                           btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+       write_extent_buffer(c, root->fs_info->chunk_tree_uuid,
+                           btrfs_header_chunk_tree_uuid(c),
+                           BTRFS_UUID_SIZE);
+
+       btrfs_set_node_key(c, &lower_key, 0);
+       btrfs_set_node_blockptr(c, 0, lower->start);
+       lower_gen = btrfs_header_generation(lower);
+       WARN_ON(lower_gen != trans->transid);
+
+       btrfs_set_node_ptr_generation(c, 0, lower_gen);
+
+       btrfs_mark_buffer_dirty(c);
+
+       old = root->node;
+       root->node = c;
+
        /* the super has an extra ref to root->node */
-       btrfs_block_release(root, root->node);
-       root->node = t;
-       t->count++;
-       path->nodes[level] = t;
+       free_extent_buffer(old);
+
+       add_root_to_dirty_list(root);
+       extent_buffer_get(c);
+       path->nodes[level] = c;
        path->slots[level] = 0;
        return 0;
 }
@@ -690,26 +1493,31 @@ static int insert_new_root(struct btrfs_trans_handle *trans, struct btrfs_root
  */
 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)
+                     *key, u64 bytenr, int slot, int level)
 {
-       struct btrfs_node *lower;
+       struct extent_buffer *lower;
        int nritems;
 
        BUG_ON(!path->nodes[level]);
-       lower = &path->nodes[level]->node;
-       nritems = btrfs_header_nritems(&lower->header);
+       lower = path->nodes[level];
+       nritems = btrfs_header_nritems(lower);
        if (slot > nritems)
                BUG();
-       if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root))
+       if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root->fs_info))
                BUG();
-       if (slot != nritems) {
-               memmove(lower->ptrs + slot + 1, lower->ptrs + slot,
-                       (nritems - slot) * sizeof(struct btrfs_key_ptr));
-       }
-       memcpy(&lower->ptrs[slot].key, key, sizeof(struct btrfs_disk_key));
-       btrfs_set_node_blockptr(lower, slot, blocknr);
-       btrfs_set_header_nritems(&lower->header, nritems + 1);
-       BUG_ON(list_empty(&path->nodes[level]->dirty));
+       if (slot < nritems) {
+               /* shift the items */
+               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, bytenr);
+       WARN_ON(trans->transid == 0);
+       btrfs_set_node_ptr_generation(lower, slot, trans->transid);
+       btrfs_set_header_nritems(lower, nritems + 1);
+       btrfs_mark_buffer_dirty(lower);
        return 0;
 }
 
@@ -725,51 +1533,78 @@ static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root
 static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
                      *root, struct btrfs_path *path, int level)
 {
-       struct btrfs_buffer *t;
-       struct btrfs_node *c;
-       struct btrfs_buffer *split_buffer;
-       struct btrfs_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];
+       WARN_ON(btrfs_header_generation(c) != trans->transid);
+       if (c == root->node) {
                /* trying to split the root, lets make a new one */
                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->fs_info) - 3)
+                       return 0;
+               if (ret < 0)
+                       return ret;
        }
-       c_nritems = btrfs_header_nritems(&c->header);
-       split_buffer = btrfs_alloc_free_block(trans, root);
-       split = &split_buffer->node;
-       btrfs_set_header_flags(&split->header, btrfs_header_flags(&c->header));
-       btrfs_set_header_level(&split->header, btrfs_header_level(&c->header));
-       btrfs_set_header_blocknr(&split->header, split_buffer->blocknr);
-       btrfs_set_header_owner(&split->header, root->root_key.objectid);
+
+       c_nritems = btrfs_header_nritems(c);
        mid = (c_nritems + 1) / 2;
-       memcpy(split->ptrs, c->ptrs + mid,
-               (c_nritems - mid) * sizeof(struct btrfs_key_ptr));
-       btrfs_set_header_nritems(&split->header, c_nritems - mid);
-       btrfs_set_header_nritems(&c->header, mid);
+       btrfs_node_key(c, &disk_key, mid);
+
+       split = btrfs_alloc_free_block(trans, root, root->fs_info->nodesize,
+                                       root->root_key.objectid,
+                                       &disk_key, level, c->start, 0);
+       if (IS_ERR(split))
+               return PTR_ERR(split);
+
+       memset_extent_buffer(split, 0, 0, sizeof(struct btrfs_header));
+       btrfs_set_header_level(split, btrfs_header_level(c));
+       btrfs_set_header_bytenr(split, split->start);
+       btrfs_set_header_generation(split, trans->transid);
+       btrfs_set_header_backref_rev(split, BTRFS_MIXED_BACKREF_REV);
+       btrfs_set_header_owner(split, root->root_key.objectid);
+       write_extent_buffer(split, root->fs_info->fsid,
+                           btrfs_header_fsid(), BTRFS_FSID_SIZE);
+       write_extent_buffer(split, root->fs_info->chunk_tree_uuid,
+                           btrfs_header_chunk_tree_uuid(split),
+                           BTRFS_UUID_SIZE);
+
+
+       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;
 
-       BUG_ON(list_empty(&t->dirty));
-       wret = insert_ptr(trans, root, path, &split->ptrs[0].key,
-                         split_buffer->blocknr, path->slots[level + 1] + 1,
+       btrfs_mark_buffer_dirty(c);
+       btrfs_mark_buffer_dirty(split);
+
+       wret = insert_ptr(trans, root, path, &disk_key, split->start,
+                         path->slots[level + 1] + 1,
                          level + 1);
        if (wret)
                ret = wret;
 
        if (path->slots[level] >= mid) {
                path->slots[level] -= mid;
-               btrfs_block_release(root, t);
-               path->nodes[level] = split_buffer;
+               free_extent_buffer(c);
+               path->nodes[level] = split;
                path->slots[level + 1] += 1;
        } else {
-               btrfs_block_release(root, split_buffer);
+               free_extent_buffer(split);
        }
        return ret;
 }
@@ -779,20 +1614,41 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
  * 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 btrfs_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 = btrfs_item_end(l->items + start);
-       data_len = data_len - btrfs_item_offset(l->items + end);
+       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)
+{
+       u32 nodesize = (root ? BTRFS_LEAF_DATA_SIZE(root->fs_info) : leaf->len);
+       int nritems = btrfs_header_nritems(leaf);
+       int ret;
+       ret = nodesize - leaf_space_used(leaf, 0, nritems);
+       if (ret < 0) {
+               printk("leaf free space ret %d, leaf data size %u, used %d nritems %d\n",
+                      ret, nodesize, 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
  *
@@ -800,105 +1656,153 @@ static int leaf_space_used(struct btrfs_leaf *l, int start, int nr)
  * room, 0 if everything worked out and < 0 if there were major errors.
  */
 static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
-                          *root, struct btrfs_path *path, int data_size)
+                          *root, struct btrfs_path *path, int data_size,
+                          int empty)
 {
-       struct btrfs_buffer *left_buf = path->nodes[0];
-       struct btrfs_leaf *left = &left_buf->leaf;
-       struct btrfs_leaf *right;
-       struct btrfs_buffer *right_buf;
-       struct btrfs_buffer *upper;
+       struct extent_buffer *left = path->nodes[0];
+       struct extent_buffer *right;
+       struct extent_buffer *upper;
+       struct btrfs_disk_key disk_key;
+       struct btrfs_fs_info *fs_info = root->fs_info;
        int slot;
-       int i;
+       u32 i;
        int free_space;
        int push_space = 0;
        int push_items = 0;
        struct btrfs_item *item;
        u32 left_nritems;
+       u32 nr;
        u32 right_nritems;
+       u32 data_end;
+       u32 this_item_size;
+       int ret;
 
        slot = path->slots[1];
        if (!path->nodes[1]) {
                return 1;
        }
        upper = path->nodes[1];
-       if (slot >= btrfs_header_nritems(&upper->node.header) - 1) {
+       if (slot >= btrfs_header_nritems(upper) - 1)
                return 1;
+
+       right = read_node_slot(fs_info, upper, slot + 1);
+       if (!extent_buffer_uptodate(right)) {
+               if (IS_ERR(right))
+                       return PTR_ERR(right);
+               return -EIO;
        }
-       right_buf = read_tree_block(root, btrfs_node_blockptr(&upper->node,
-                                                             slot + 1));
-       right = &right_buf->leaf;
        free_space = btrfs_leaf_free_space(root, right);
-       if (free_space < data_size + sizeof(struct btrfs_item)) {
-               btrfs_block_release(root, right_buf);
+       if (free_space < data_size) {
+               free_extent_buffer(right);
                return 1;
        }
+
        /* cow and double check */
-       btrfs_cow_block(trans, root, right_buf, upper, slot + 1, &right_buf);
-       right = &right_buf->leaf;
+       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)) {
-               btrfs_block_release(root, right_buf);
+       if (free_space < data_size) {
+               free_extent_buffer(right);
+               return 1;
+       }
+
+       left_nritems = btrfs_header_nritems(left);
+       if (left_nritems == 0) {
+               free_extent_buffer(right);
                return 1;
        }
 
-       left_nritems = btrfs_header_nritems(&left->header);
-       for (i = left_nritems - 1; i >= 0; i--) {
-               item = left->items + i;
+       if (empty)
+               nr = 0;
+       else
+               nr = 1;
+
+       i = left_nritems - 1;
+       while (i >= nr) {
+               item = btrfs_item_nr(i);
+
                if (path->slots[0] == i)
                        push_space += data_size + sizeof(*item);
-               if (btrfs_item_size(item) + sizeof(*item) + push_space >
-                   free_space)
+
+               this_item_size = btrfs_item_size(left, item);
+               if (this_item_size + sizeof(*item) + push_space > free_space)
                        break;
                push_items++;
-               push_space += btrfs_item_size(item) + sizeof(*item);
+               push_space += this_item_size + sizeof(*item);
+               if (i == 0)
+                       break;
+               i--;
        }
+
        if (push_items == 0) {
-               btrfs_block_release(root, right_buf);
+               free_extent_buffer(right);
                return 1;
        }
-       right_nritems = btrfs_header_nritems(&right->header);
+
+       if (!empty && push_items == left_nritems)
+               WARN_ON(1);
+
        /* push left to right */
-       push_space = btrfs_item_end(left->items + left_nritems - push_items);
-       push_space -= leaf_data_end(root, left);
+       right_nritems = btrfs_header_nritems(right);
+
+       push_space = btrfs_item_end_nr(left, left_nritems - push_items);
+       push_space -= leaf_data_end(fs_info, left);
+
        /* make room in the right data area */
-       memmove(btrfs_leaf_data(right) + leaf_data_end(root, right) -
-               push_space, btrfs_leaf_data(right) + leaf_data_end(root, right),
-               BTRFS_LEAF_DATA_SIZE(root) - leaf_data_end(root, right));
+       data_end = leaf_data_end(fs_info, right);
+       memmove_extent_buffer(right,
+                             btrfs_leaf_data(right) + data_end - push_space,
+                             btrfs_leaf_data(right) + data_end,
+                             BTRFS_LEAF_DATA_SIZE(root->fs_info) - data_end);
+
        /* copy from the left data area */
-       memcpy(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) - push_space,
-               btrfs_leaf_data(left) + leaf_data_end(root, left), push_space);
-       memmove(right->items + push_items, right->items,
-               right_nritems * sizeof(struct btrfs_item));
+       copy_extent_buffer(right, left, btrfs_leaf_data(right) +
+                    BTRFS_LEAF_DATA_SIZE(root->fs_info) - push_space,
+                    btrfs_leaf_data(left) + leaf_data_end(fs_info, 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_nritems - push_items,
-               push_items * sizeof(struct btrfs_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_nritems += push_items;
-       btrfs_set_header_nritems(&right->header, right_nritems);
-       push_space = BTRFS_LEAF_DATA_SIZE(root);
+       btrfs_set_header_nritems(right, right_nritems);
+       push_space = BTRFS_LEAF_DATA_SIZE(root->fs_info);
        for (i = 0; i < right_nritems; i++) {
-               btrfs_set_item_offset(right->items + i, push_space -
-                                     btrfs_item_size(right->items + i));
-               push_space = btrfs_item_offset(right->items + i);
+               item = btrfs_item_nr(i);
+               push_space -= btrfs_item_size(right, item);
+               btrfs_set_item_offset(right, item, push_space);
        }
+
        left_nritems -= push_items;
-       btrfs_set_header_nritems(&left->header, left_nritems);
+       btrfs_set_header_nritems(left, left_nritems);
 
-       BUG_ON(list_empty(&left_buf->dirty));
-       BUG_ON(list_empty(&right_buf->dirty));
-       memcpy(&upper->node.ptrs[slot + 1].key,
-               &right->items[0].key, sizeof(struct btrfs_disk_key));
-       BUG_ON(list_empty(&upper->dirty));
+       if (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_nritems) {
                path->slots[0] -= left_nritems;
-               btrfs_block_release(root, path->nodes[0]);
-               path->nodes[0] = right_buf;
+               free_extent_buffer(path->nodes[0]);
+               path->nodes[0] = right;
                path->slots[1] += 1;
        } else {
-               btrfs_block_release(root, right_buf);
+               free_extent_buffer(right);
        }
        return 0;
 }
@@ -907,12 +1811,13 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
  * least data_size bytes.  returns zero if the push worked, nonzero otherwise
  */
 static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
-                         *root, struct btrfs_path *path, int data_size)
+                         *root, struct btrfs_path *path, int data_size,
+                         int empty)
 {
-       struct btrfs_buffer *right_buf = path->nodes[0];
-       struct btrfs_leaf *right = &right_buf->leaf;
-       struct btrfs_buffer *t;
-       struct btrfs_leaf *left;
+       struct btrfs_disk_key disk_key;
+       struct extent_buffer *right = path->nodes[0];
+       struct extent_buffer *left;
+       struct btrfs_fs_info *fs_info = root->fs_info;
        int slot;
        int i;
        int free_space;
@@ -920,104 +1825,145 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
        int push_items = 0;
        struct btrfs_item *item;
        u32 old_left_nritems;
+       u32 right_nritems;
+       u32 nr;
        int ret = 0;
-       int wret;
+       u32 this_item_size;
+       u32 old_left_item_size;
 
        slot = path->slots[1];
-       if (slot == 0) {
+       if (slot == 0)
                return 1;
-       }
-       if (!path->nodes[1]) {
+       if (!path->nodes[1])
+               return 1;
+
+       right_nritems = btrfs_header_nritems(right);
+       if (right_nritems == 0) {
                return 1;
        }
-       t = read_tree_block(root, btrfs_node_blockptr(&path->nodes[1]->node,
-                                                     slot - 1));
-       left = &t->leaf;
+
+       left = read_node_slot(fs_info, path->nodes[1], slot - 1);
        free_space = btrfs_leaf_free_space(root, left);
-       if (free_space < data_size + sizeof(struct btrfs_item)) {
-               btrfs_block_release(root, t);
+       if (free_space < data_size) {
+               free_extent_buffer(left);
                return 1;
        }
 
        /* cow and double check */
-       btrfs_cow_block(trans, root, t, path->nodes[1], slot - 1, &t);
-       left = &t->leaf;
+       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;
+       }
+
        free_space = btrfs_leaf_free_space(root, left);
-       if (free_space < data_size + sizeof(struct btrfs_item)) {
-               btrfs_block_release(root, t);
+       if (free_space < data_size) {
+               free_extent_buffer(left);
                return 1;
        }
 
-       for (i = 0; i < btrfs_header_nritems(&right->header); i++) {
-               item = right->items + i;
+       if (empty)
+               nr = right_nritems;
+       else
+               nr = right_nritems - 1;
+
+       for (i = 0; i < nr; i++) {
+               item = btrfs_item_nr(i);
+
                if (path->slots[0] == i)
                        push_space += data_size + sizeof(*item);
-               if (btrfs_item_size(item) + sizeof(*item) + push_space >
-                   free_space)
+
+               this_item_size = btrfs_item_size(right, item);
+               if (this_item_size + sizeof(*item) + push_space > free_space)
                        break;
+
                push_items++;
-               push_space += btrfs_item_size(item) + sizeof(*item);
+               push_space += this_item_size + sizeof(*item);
        }
+
        if (push_items == 0) {
-               btrfs_block_release(root, t);
+               free_extent_buffer(left);
                return 1;
        }
-       /* push data from right to left */
-       memcpy(left->items + btrfs_header_nritems(&left->header),
-               right->items, push_items * sizeof(struct btrfs_item));
-       push_space = BTRFS_LEAF_DATA_SIZE(root) -
-                    btrfs_item_offset(right->items + push_items -1);
-       memcpy(btrfs_leaf_data(left) + leaf_data_end(root, left) - push_space,
-               btrfs_leaf_data(right) +
-               btrfs_item_offset(right->items + push_items - 1),
-               push_space);
-       old_left_nritems = btrfs_header_nritems(&left->header);
-       BUG_ON(old_left_nritems < 0);
+       if (!empty && push_items == btrfs_header_nritems(right))
+               WARN_ON(1);
 
+       /* push data from right to left */
+       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->fs_info) -
+                    btrfs_item_offset_nr(right, push_items -1);
+
+       copy_extent_buffer(left, right, btrfs_leaf_data(left) +
+                    leaf_data_end(fs_info, 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);
+
+       old_left_item_size = btrfs_item_offset_nr(left, old_left_nritems - 1);
        for (i = old_left_nritems; i < old_left_nritems + push_items; i++) {
-               u32 ioff = btrfs_item_offset(left->items + i);
-               btrfs_set_item_offset(left->items + i, ioff -
-                                    (BTRFS_LEAF_DATA_SIZE(root) -
-                                     btrfs_item_offset(left->items +
-                                                       old_left_nritems - 1)));
+               u32 ioff;
+
+               item = btrfs_item_nr(i);
+               ioff = btrfs_item_offset(left, item);
+               btrfs_set_item_offset(left, item,
+                     ioff - (BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+                             old_left_item_size));
        }
-       btrfs_set_header_nritems(&left->header, old_left_nritems + push_items);
+       btrfs_set_header_nritems(left, old_left_nritems + push_items);
 
        /* fixup right node */
-       push_space = btrfs_item_offset(right->items + push_items - 1) -
-                    leaf_data_end(root, right);
-       memmove(btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) -
-               push_space, btrfs_leaf_data(right) +
-               leaf_data_end(root, right), push_space);
-       memmove(right->items, right->items + push_items,
-               (btrfs_header_nritems(&right->header) - push_items) *
-               sizeof(struct btrfs_item));
-       btrfs_set_header_nritems(&right->header,
-                                btrfs_header_nritems(&right->header) -
-                                push_items);
-       push_space = BTRFS_LEAF_DATA_SIZE(root);
-
-       for (i = 0; i < btrfs_header_nritems(&right->header); i++) {
-               btrfs_set_item_offset(right->items + i, push_space -
-                                     btrfs_item_size(right->items + i));
-               push_space = btrfs_item_offset(right->items + i);
-       }
-
-       BUG_ON(list_empty(&t->dirty));
-       BUG_ON(list_empty(&right_buf->dirty));
-
-       wret = fixup_low_keys(trans, root, path, &right->items[0].key, 1);
-       if (wret)
-               ret = wret;
+       if (push_items > right_nritems) {
+               printk("push items %d nr %u\n", push_items, right_nritems);
+               WARN_ON(1);
+       }
+
+       if (push_items < right_nritems) {
+               push_space = btrfs_item_offset_nr(right, push_items - 1) -
+                                                 leaf_data_end(fs_info, right);
+               memmove_extent_buffer(right, btrfs_leaf_data(right) +
+                                     BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+                                     push_space,
+                                     btrfs_leaf_data(right) +
+                                     leaf_data_end(fs_info, 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 -= push_items;
+       btrfs_set_header_nritems(right, right_nritems);
+       push_space = BTRFS_LEAF_DATA_SIZE(root->fs_info);
+       for (i = 0; i < right_nritems; i++) {
+               item = btrfs_item_nr(i);
+               push_space = push_space - btrfs_item_size(right, item);
+               btrfs_set_item_offset(right, item, push_space);
+       }
+
+       btrfs_mark_buffer_dirty(left);
+       if (right_nritems)
+               btrfs_mark_buffer_dirty(right);
+
+       btrfs_item_key(right, &disk_key, 0);
+       btrfs_fixup_low_keys(root, path, &disk_key, 1);
 
        /* then fixup the leaf pointer in the path */
        if (path->slots[0] < push_items) {
                path->slots[0] += old_left_nritems;
-               btrfs_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 {
-               btrfs_block_release(root, t);
+               free_extent_buffer(left);
                path->slots[0] -= push_items;
        }
        BUG_ON(path->slots[0] < 0);
@@ -1030,100 +1976,503 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
  *
  * returns 0 if all went well and < 0 on failure.
  */
-static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
-                     *root, struct btrfs_path *path, int data_size)
+static noinline int copy_for_split(struct btrfs_trans_handle *trans,
+                              struct btrfs_root *root,
+                              struct btrfs_path *path,
+                              struct extent_buffer *l,
+                              struct extent_buffer *right,
+                              int slot, int mid, int nritems)
 {
-       struct btrfs_buffer *l_buf;
-       struct btrfs_leaf *l;
-       u32 nritems;
-       int mid;
-       int slot;
-       struct btrfs_leaf *right;
-       struct btrfs_buffer *right_buffer;
-       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;
+       struct btrfs_disk_key disk_key;
+
+       nritems = nritems - mid;
+       btrfs_set_header_nritems(right, nritems);
+       data_copy_size = btrfs_item_end_nr(l, mid) -
+               leaf_data_end(root->fs_info, 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->fs_info) -
+                    data_copy_size, btrfs_leaf_data(l) +
+                    leaf_data_end(root->fs_info, l), data_copy_size);
+
+       rt_data_off = BTRFS_LEAF_DATA_SIZE(root->fs_info) -
+                     btrfs_item_end_nr(l, mid);
+
+       for (i = 0; i < nritems; i++) {
+               struct btrfs_item *item = btrfs_item_nr(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;
+       btrfs_item_key(right, &disk_key, 0);
+       wret = insert_ptr(trans, root, path, &disk_key, right->start,
+                         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) {
+               free_extent_buffer(path->nodes[0]);
+               path->nodes[0] = right;
+               path->slots[0] -= mid;
+               path->slots[1] += 1;
+       } else {
+               free_extent_buffer(right);
+       }
+
+       BUG_ON(path->slots[0] < 0);
+
+       return ret;
+}
+
+/*
+ * split the path's leaf in two, making sure there is at least data_size
+ * available for the resulting leaf level of the path.
+ *
+ * returns 0 if all went well and < 0 on failure.
+ */
+static noinline int split_leaf(struct btrfs_trans_handle *trans,
+                              struct btrfs_root *root,
+                              struct btrfs_key *ins_key,
+                              struct btrfs_path *path, int data_size,
+                              int extend)
+{
+       struct btrfs_disk_key disk_key;
+       struct extent_buffer *l;
+       u32 nritems;
+       int mid;
+       int slot;
+       struct extent_buffer *right;
+       int ret = 0;
+       int wret;
+       int split;
+       int num_doubles = 0;
+
+       l = path->nodes[0];
+       slot = path->slots[0];
+       if (extend && data_size + btrfs_item_size_nr(l, slot) +
+           sizeof(struct btrfs_item) > BTRFS_LEAF_DATA_SIZE(root->fs_info))
+               return -EOVERFLOW;
 
        /* 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(trans, root, path, data_size);
+       if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) {
+               wret = push_leaf_right(trans, root, path, data_size, 0);
                if (wret < 0)
                        return wret;
-       }
-       l_buf = path->nodes[0];
-       l = &l_buf->leaf;
+               if (wret) {
+                       wret = push_leaf_left(trans, root, path, data_size, 0);
+                       if (wret < 0)
+                               return wret;
+               }
+               l = path->nodes[0];
 
-       /* did the pushes work? */
-       if (btrfs_leaf_free_space(root, l) >=
-           sizeof(struct btrfs_item) + data_size)
-               return 0;
+               /* did the pushes work? */
+               if (btrfs_leaf_free_space(root, l) >= data_size)
+                       return 0;
+       }
 
        if (!path->nodes[1]) {
                ret = insert_new_root(trans, root, path, 1);
                if (ret)
                        return ret;
        }
+again:
+       split = 1;
+       l = path->nodes[0];
        slot = path->slots[0];
-       nritems = btrfs_header_nritems(&l->header);
-       mid = (nritems + 1)/ 2;
-       right_buffer = btrfs_alloc_free_block(trans, root);
-       BUG_ON(!right_buffer);
-       BUG_ON(mid == nritems);
-       right = &right_buffer->leaf;
-       memset(&right->header, 0, sizeof(right->header));
+       nritems = btrfs_header_nritems(l);
+       mid = (nritems + 1) / 2;
+
        if (mid <= slot) {
-               /* FIXME, just alloc a new leaf here */
-               if (leaf_space_used(l, mid, nritems - mid) + space_needed >
-                       BTRFS_LEAF_DATA_SIZE(root))
-                       BUG();
+               if (nritems == 1 ||
+                   leaf_space_used(l, mid, nritems - mid) + data_size >
+                       BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+                       if (slot >= nritems) {
+                               split = 0;
+                       } else {
+                               mid = slot;
+                               if (mid != nritems &&
+                                   leaf_space_used(l, mid, nritems - mid) +
+                                   data_size >
+                                   BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+                                       split = 2;
+                               }
+                       }
+               }
        } else {
-               /* FIXME, just alloc a new leaf here */
-               if (leaf_space_used(l, 0, mid + 1) + space_needed >
-                       BTRFS_LEAF_DATA_SIZE(root))
-                       BUG();
-       }
-       btrfs_set_header_nritems(&right->header, nritems - mid);
-       btrfs_set_header_blocknr(&right->header, right_buffer->blocknr);
-       btrfs_set_header_level(&right->header, 0);
-       btrfs_set_header_owner(&right->header, root->root_key.objectid);
-       data_copy_size = btrfs_item_end(l->items + mid) -
-                        leaf_data_end(root, l);
-       memcpy(right->items, l->items + mid,
-              (nritems - mid) * sizeof(struct btrfs_item));
-       memcpy(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(l->items + mid);
-
-       for (i = 0; i < btrfs_header_nritems(&right->header); i++) {
-               u32 ioff = btrfs_item_offset(right->items + i);
-               btrfs_set_item_offset(right->items + i, ioff + rt_data_off);
-       }
-
-       btrfs_set_header_nritems(&l->header, mid);
+               if (leaf_space_used(l, 0, mid) + data_size >
+                       BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+                       if (!extend && data_size && slot == 0) {
+                               split = 0;
+                       } else if ((extend || !data_size) && slot == 0) {
+                               mid = 1;
+                       } else {
+                               mid = slot;
+                               if (mid != nritems &&
+                                   leaf_space_used(l, mid, nritems - mid) +
+                                   data_size >
+                                   BTRFS_LEAF_DATA_SIZE(root->fs_info)) {
+                                       split = 2 ;
+                               }
+                       }
+               }
+       }
+       
+       if (split == 0)
+               btrfs_cpu_key_to_disk(&disk_key, ins_key);
+       else
+               btrfs_item_key(l, &disk_key, mid);
+
+       right = btrfs_alloc_free_block(trans, root, root->fs_info->nodesize,
+                                       root->root_key.objectid,
+                                       &disk_key, 0, l->start, 0);
+       if (IS_ERR(right)) {
+               BUG_ON(1);
+               return PTR_ERR(right);
+       }
+
+       memset_extent_buffer(right, 0, 0, sizeof(struct btrfs_header));
+       btrfs_set_header_bytenr(right, right->start);
+       btrfs_set_header_generation(right, trans->transid);
+       btrfs_set_header_backref_rev(right, BTRFS_MIXED_BACKREF_REV);
+       btrfs_set_header_owner(right, root->root_key.objectid);
+       btrfs_set_header_level(right, 0);
+       write_extent_buffer(right, root->fs_info->fsid,
+                           btrfs_header_fsid(), BTRFS_FSID_SIZE);
+
+       write_extent_buffer(right, root->fs_info->chunk_tree_uuid,
+                           btrfs_header_chunk_tree_uuid(right),
+                           BTRFS_UUID_SIZE);
+
+       if (split == 0) {
+               if (mid <= slot) {
+                       btrfs_set_header_nritems(right, 0);
+                       wret = insert_ptr(trans, root, path,
+                                         &disk_key, right->start,
+                                         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;
+               } else {
+                       btrfs_set_header_nritems(right, 0);
+                       wret = insert_ptr(trans, root, path,
+                                         &disk_key,
+                                         right->start,
+                                         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) {
+                               btrfs_fixup_low_keys(root, path,
+                                                    &disk_key, 1);
+                       }
+               }
+               btrfs_mark_buffer_dirty(right);
+               return ret;
+       }
+
+       ret = copy_for_split(trans, root, path, l, right, slot, mid, nritems);
+       BUG_ON(ret);
+
+       if (split == 2) {
+               BUG_ON(num_doubles != 0);
+               num_doubles++;
+               goto again;
+       }
+
+       return ret;
+}
+
+/*
+ * This function splits a single item into two items,
+ * giving 'new_key' to the new item and splitting the
+ * old one at split_offset (from the start of the item).
+ *
+ * The path may be released by this operation.  After
+ * the split, the path is pointing to the old item.  The
+ * new item is going to be in the same node as the old one.
+ *
+ * Note, the item being split must be smaller enough to live alone on
+ * a tree block with room for one extra struct btrfs_item
+ *
+ * This allows us to split the item in place, keeping a lock on the
+ * leaf the entire time.
+ */
+int btrfs_split_item(struct btrfs_trans_handle *trans,
+                    struct btrfs_root *root,
+                    struct btrfs_path *path,
+                    struct btrfs_key *new_key,
+                    unsigned long split_offset)
+{
+       u32 item_size;
+       struct extent_buffer *leaf;
+       struct btrfs_key orig_key;
+       struct btrfs_item *item;
+       struct btrfs_item *new_item;
+       int ret = 0;
+       int slot;
+       u32 nritems;
+       u32 orig_offset;
+       struct btrfs_disk_key disk_key;
+       char *buf;
+
+       leaf = path->nodes[0];
+       btrfs_item_key_to_cpu(leaf, &orig_key, path->slots[0]);
+       if (btrfs_leaf_free_space(root, leaf) >= sizeof(struct btrfs_item))
+               goto split;
+
+       item_size = btrfs_item_size_nr(leaf, path->slots[0]);
+       btrfs_release_path(path);
+
+       path->search_for_split = 1;
+
+       ret = btrfs_search_slot(trans, root, &orig_key, path, 0, 1);
+       path->search_for_split = 0;
+
+       /* if our item isn't there or got smaller, return now */
+       if (ret != 0 || item_size != btrfs_item_size_nr(path->nodes[0],
+                                                       path->slots[0])) {
+               return -EAGAIN;
+       }
+
+       ret = split_leaf(trans, root, &orig_key, path, 0, 0);
+       BUG_ON(ret);
+
+       BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item));
+       leaf = path->nodes[0];
+
+split:
+       item = btrfs_item_nr(path->slots[0]);
+       orig_offset = btrfs_item_offset(leaf, item);
+       item_size = btrfs_item_size(leaf, item);
+
+
+       buf = kmalloc(item_size, GFP_NOFS);
+       BUG_ON(!buf);
+       read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf,
+                           path->slots[0]), item_size);
+       slot = path->slots[0] + 1;
+       leaf = path->nodes[0];
+
+       nritems = btrfs_header_nritems(leaf);
+
+       if (slot < nritems) {
+               /* shift the items */
+               memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1),
+                             btrfs_item_nr_offset(slot),
+                             (nritems - slot) * sizeof(struct btrfs_item));
+
+       }
+
+       btrfs_cpu_key_to_disk(&disk_key, new_key);
+       btrfs_set_item_key(leaf, &disk_key, slot);
+
+       new_item = btrfs_item_nr(slot);
+
+       btrfs_set_item_offset(leaf, new_item, orig_offset);
+       btrfs_set_item_size(leaf, new_item, item_size - split_offset);
+
+       btrfs_set_item_offset(leaf, item,
+                             orig_offset + item_size - split_offset);
+       btrfs_set_item_size(leaf, item, split_offset);
+
+       btrfs_set_header_nritems(leaf, nritems + 1);
+
+       /* write the data for the start of the original item */
+       write_extent_buffer(leaf, buf,
+                           btrfs_item_ptr_offset(leaf, path->slots[0]),
+                           split_offset);
+
+       /* write the data for the new item */
+       write_extent_buffer(leaf, buf + split_offset,
+                           btrfs_item_ptr_offset(leaf, slot),
+                           item_size - split_offset);
+       btrfs_mark_buffer_dirty(leaf);
+
        ret = 0;
-       wret = insert_ptr(trans, root, path, &right->items[0].key,
-                         right_buffer->blocknr, path->slots[1] + 1, 1);
-       if (wret)
-               ret = wret;
-       BUG_ON(list_empty(&right_buffer->dirty));
-       BUG_ON(list_empty(&l_buf->dirty));
-       BUG_ON(path->slots[0] != slot);
-       if (mid <= slot) {
-               btrfs_block_release(root, path->nodes[0]);
-               path->nodes[0] = right_buffer;
-               path->slots[0] -= mid;
-               path->slots[1] += 1;
-       } else
-               btrfs_block_release(root, right_buffer);
-       BUG_ON(path->slots[0] < 0);
+       if (btrfs_leaf_free_space(root, leaf) < 0) {
+               btrfs_print_leaf(root, leaf);
+               BUG();
+       }
+       kfree(buf);
+       return ret;
+}
+
+int btrfs_truncate_item(struct btrfs_root *root, struct btrfs_path *path,
+                       u32 new_size, int from_end)
+{
+       int ret = 0;
+       int slot;
+       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;
+
+       leaf = path->nodes[0];
+       slot = path->slots[0];
+
+       old_size = btrfs_item_size_nr(leaf, slot);
+       if (old_size == new_size)
+               return 0;
+
+       nritems = btrfs_header_nritems(leaf);
+       data_end = leaf_data_end(root->fs_info, leaf);
+
+       old_data_start = btrfs_item_offset_nr(leaf, slot);
+
+       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(i);
+               ioff = btrfs_item_offset(leaf, item);
+               btrfs_set_item_offset(leaf, item, ioff + size_diff);
+       }
+
+       /* shift the data */
+       if (from_end) {
+               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);
+       } else {
+               struct btrfs_disk_key disk_key;
+               u64 offset;
+
+               btrfs_item_key(leaf, &disk_key, slot);
+
+               if (btrfs_disk_key_type(&disk_key) == BTRFS_EXTENT_DATA_KEY) {
+                       unsigned long ptr;
+                       struct btrfs_file_extent_item *fi;
+
+                       fi = btrfs_item_ptr(leaf, slot,
+                                           struct btrfs_file_extent_item);
+                       fi = (struct btrfs_file_extent_item *)(
+                            (unsigned long)fi - size_diff);
+
+                       if (btrfs_file_extent_type(leaf, fi) ==
+                           BTRFS_FILE_EXTENT_INLINE) {
+                               ptr = btrfs_item_ptr_offset(leaf, slot);
+                               memmove_extent_buffer(leaf, ptr,
+                                       (unsigned long)fi,
+                                       offsetof(struct btrfs_file_extent_item,
+                                                disk_bytenr));
+                       }
+               }
+
+               memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                             data_end + size_diff, btrfs_leaf_data(leaf) +
+                             data_end, old_data_start - data_end);
+
+               offset = btrfs_disk_key_offset(&disk_key);
+               btrfs_set_disk_key_offset(&disk_key, offset + size_diff);
+               btrfs_set_item_key(leaf, &disk_key, slot);
+               if (slot == 0)
+                       btrfs_fixup_low_keys(root, path, &disk_key, 1);
+       }
+
+       item = btrfs_item_nr(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();
+       }
+       return ret;
+}
+
+int btrfs_extend_item(struct btrfs_root *root, struct btrfs_path *path,
+                     u32 data_size)
+{
+       int ret = 0;
+       int slot;
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
+       u32 nritems;
+       unsigned int data_end;
+       unsigned int old_data;
+       unsigned int old_size;
+       int i;
+
+       leaf = path->nodes[0];
+
+       nritems = btrfs_header_nritems(leaf);
+       data_end = leaf_data_end(root->fs_info, 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);
+       if (slot >= nritems) {
+               btrfs_print_leaf(root, leaf);
+               printk("slot %d too large, nritems %d\n", slot, nritems);
+               BUG_ON(1);
+       }
+
+       /*
+        * 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(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(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();
+       }
        return ret;
 }
 
@@ -1131,83 +2480,110 @@ static int split_leaf(struct btrfs_trans_handle *trans, struct btrfs_root
  * 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_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root
-                           *root, struct btrfs_path *path, struct btrfs_key
-                           *cpu_key, u32 data_size)
+int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
+                           struct btrfs_root *root,
+                           struct btrfs_path *path,
+                           struct btrfs_key *cpu_key, u32 *data_size,
+                           int nr)
 {
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
        int ret = 0;
        int slot;
-       int slot_orig;
-       struct btrfs_leaf *leaf;
-       struct btrfs_buffer *leaf_buf;
+       int i;
        u32 nritems;
+       u32 total_size = 0;
+       u32 total_data = 0;
        unsigned int data_end;
        struct btrfs_disk_key disk_key;
 
-       btrfs_cpu_key_to_disk(&disk_key, cpu_key);
+       for (i = 0; i < nr; i++) {
+               total_data += data_size[i];
+       }
 
        /* create a root if there isn't one */
        if (!root->node)
                BUG();
-       ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1);
+
+       total_size = total_data + nr * sizeof(struct btrfs_item);
+       ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
        if (ret == 0) {
                return -EEXIST;
        }
        if (ret < 0)
                goto out;
 
-       slot_orig = path->slots[0];
-       leaf_buf = path->nodes[0];
-       leaf = &leaf_buf->leaf;
+       leaf = path->nodes[0];
 
-       nritems = btrfs_header_nritems(&leaf->header);
-       data_end = leaf_data_end(root, leaf);
+       nritems = btrfs_header_nritems(leaf);
+       data_end = leaf_data_end(root->fs_info, leaf);
 
-       if (btrfs_leaf_free_space(root, leaf) <
-           sizeof(struct btrfs_item) + data_size)
+       if (btrfs_leaf_free_space(root, leaf) < total_size) {
+               btrfs_print_leaf(root, leaf);
+               printk("not enough freespace need %u have %d\n",
+                      total_size, btrfs_leaf_free_space(root, leaf));
                BUG();
+       }
 
        slot = path->slots[0];
        BUG_ON(slot < 0);
-       if (slot != nritems) {
-               int i;
-               unsigned int old_data = btrfs_item_end(leaf->items + slot);
 
+       if (slot < nritems) {
+               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++) {
-                       u32 ioff = btrfs_item_offset(leaf->items + i);
-                       btrfs_set_item_offset(leaf->items + i,
-                                             ioff - data_size);
+                       u32 ioff;
+
+                       item = btrfs_item_nr(i);
+                       ioff = btrfs_item_offset(leaf, item);
+                       btrfs_set_item_offset(leaf, item, ioff - total_data);
                }
 
                /* shift the items */
-               memmove(leaf->items + slot + 1, leaf->items + slot,
-                       (nritems - slot) * sizeof(struct btrfs_item));
+               memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
+                             btrfs_item_nr_offset(slot),
+                             (nritems - slot) * sizeof(struct btrfs_item));
 
                /* shift the data */
-               memmove(btrfs_leaf_data(leaf) + data_end - data_size,
-                       btrfs_leaf_data(leaf) +
-                       data_end, old_data - data_end);
+               memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                             data_end - total_data, btrfs_leaf_data(leaf) +
+                             data_end, old_data - data_end);
                data_end = old_data;
        }
+
        /* setup the item for the new data */
-       memcpy(&leaf->items[slot].key, &disk_key,
-               sizeof(struct btrfs_disk_key));
-       btrfs_set_item_offset(leaf->items + slot, data_end - data_size);
-       btrfs_set_item_size(leaf->items + slot, data_size);
-       btrfs_set_header_nritems(&leaf->header, nritems + 1);
+       for (i = 0; i < nr; i++) {
+               btrfs_cpu_key_to_disk(&disk_key, cpu_key + i);
+               btrfs_set_item_key(leaf, &disk_key, slot + i);
+               item = btrfs_item_nr(slot + i);
+               btrfs_set_item_offset(leaf, item, data_end - data_size[i]);
+               data_end -= data_size[i];
+               btrfs_set_item_size(leaf, item, data_size[i]);
+       }
+       btrfs_set_header_nritems(leaf, nritems + nr);
+       btrfs_mark_buffer_dirty(leaf);
 
        ret = 0;
-       if (slot == 0)
-               ret = fixup_low_keys(trans, root, path, &disk_key, 1);
+       if (slot == 0) {
+               btrfs_cpu_key_to_disk(&disk_key, cpu_key);
+               btrfs_fixup_low_keys(root, path, &disk_key, 1);
+       }
 
-       BUG_ON(list_empty(&leaf_buf->dirty));
-       if (btrfs_leaf_free_space(root, leaf) < 0)
+       if (btrfs_leaf_free_space(root, leaf) < 0) {
+               btrfs_print_leaf(root, leaf);
                BUG();
-       check_leaf(root, path, 0);
+       }
+
 out:
        return ret;
 }
@@ -1221,16 +2597,22 @@ int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
                      data_size)
 {
        int ret = 0;
-       struct btrfs_path path;
-       u8 *ptr;
+       struct btrfs_path *path;
+       struct extent_buffer *leaf;
+       unsigned long ptr;
+
+       path = btrfs_alloc_path();
+       if (!path)
+               return -ENOMEM;
 
-       btrfs_init_path(&path);
-       ret = btrfs_insert_empty_item(trans, root, &path, cpu_key, data_size);
+       ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
        if (!ret) {
-               ptr = btrfs_item_ptr(&path.nodes[0]->leaf, path.slots[0], u8);
-               memcpy(ptr, data, data_size);
+               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_release_path(root, &path);
+       btrfs_free_path(path);
        return ret;
 }
 
@@ -1241,34 +2623,62 @@ int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
  * 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 btrfs_trans_handle *trans, struct btrfs_root *root,
-                  struct btrfs_path *path, int level, int slot)
+int btrfs_del_ptr(struct btrfs_root *root, struct btrfs_path *path,
+               int level, int slot)
 {
-       struct btrfs_node *node;
-       struct btrfs_buffer *parent = path->nodes[level];
+       struct extent_buffer *parent = path->nodes[level];
        u32 nritems;
        int ret = 0;
-       int wret;
 
-       node = &parent->node;
-       nritems = btrfs_header_nritems(&node->header);
-       if (slot != nritems -1) {
-               memmove(node->ptrs + slot, node->ptrs + slot + 1,
-                       sizeof(struct btrfs_key_ptr) * (nritems - slot - 1));
+       nritems = btrfs_header_nritems(parent);
+       if (slot < nritems - 1) {
+               /* shift the items */
+               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(&node->header, nritems);
+       btrfs_set_header_nritems(parent, nritems);
        if (nritems == 0 && parent == root->node) {
-               BUG_ON(btrfs_header_level(&root->node->node.header) != 1);
+               BUG_ON(btrfs_header_level(root->node) != 1);
                /* just turn the root into a leaf and break */
-               btrfs_set_header_level(&root->node->node.header, 0);
+               btrfs_set_header_level(root->node, 0);
        } else if (slot == 0) {
-               wret = fixup_low_keys(trans, root, path, &node->ptrs[0].key,
-                                     level + 1);
-               if (wret)
-                       ret = wret;
+               struct btrfs_disk_key disk_key;
+
+               btrfs_node_key(parent, &disk_key, 0);
+               btrfs_fixup_low_keys(root, path, &disk_key, level + 1);
        }
-       BUG_ON(list_empty(&parent->dirty));
+       btrfs_mark_buffer_dirty(parent);
+       return ret;
+}
+
+/*
+ * a helper function to delete the leaf pointed to by path->slots[1] and
+ * path->nodes[1].
+ *
+ * This deletes the pointer in path->nodes[1] and frees the leaf
+ * block extent.  zero is returned if it all worked out, < 0 otherwise.
+ *
+ * The path must have already been setup for deleting the leaf, including
+ * all the proper balancing.  path->nodes[1] must be locked.
+ */
+static noinline int btrfs_del_leaf(struct btrfs_trans_handle *trans,
+                                  struct btrfs_root *root,
+                                  struct btrfs_path *path,
+                                  struct extent_buffer *leaf)
+{
+       int ret;
+
+       WARN_ON(btrfs_header_generation(leaf) != trans->transid);
+       ret = btrfs_del_ptr(root, path, 1, path->slots[1]);
+       if (ret)
+               return ret;
+
+       ret = btrfs_free_extent(trans, root, leaf->start, leaf->len,
+                               0, root->root_key.objectid, 0, 0);
        return ret;
 }
 
@@ -1276,152 +2686,163 @@ static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
  * delete the item at the leaf level in path.  If that empties
  * the leaf, remove it from the tree
  */
-int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                  struct btrfs_path *path)
+int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+                   struct btrfs_path *path, int slot, int nr)
 {
-       int slot;
-       struct btrfs_leaf *leaf;
-       struct btrfs_buffer *leaf_buf;
-       int doff;
-       int dsize;
+       struct extent_buffer *leaf;
+       struct btrfs_item *item;
+       int last_off;
+       int dsize = 0;
        int ret = 0;
        int wret;
+       int i;
        u32 nritems;
 
-       leaf_buf = path->nodes[0];
-       leaf = &leaf_buf->leaf;
-       slot = path->slots[0];
-       doff = btrfs_item_offset(leaf->items + slot);
-       dsize = btrfs_item_size(leaf->items + slot);
-       nritems = btrfs_header_nritems(&leaf->header);
-
-       if (slot != nritems - 1) {
-               int i;
-               int data_end = leaf_data_end(root, leaf);
-               memmove(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 = btrfs_item_offset(leaf->items + i);
-                       btrfs_set_item_offset(leaf->items + i, ioff + dsize);
+       leaf = path->nodes[0];
+       last_off = btrfs_item_offset_nr(leaf, slot + nr - 1);
+
+       for (i = 0; i < nr; i++)
+               dsize += btrfs_item_size_nr(leaf, slot + i);
+
+       nritems = btrfs_header_nritems(leaf);
+
+       if (slot + nr != nritems) {
+               int data_end = leaf_data_end(root->fs_info, leaf);
+
+               memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
+                             data_end + dsize,
+                             btrfs_leaf_data(leaf) + data_end,
+                             last_off - data_end);
+
+               for (i = slot + nr; i < nritems; i++) {
+                       u32 ioff;
+
+                       item = btrfs_item_nr(i);
+                       ioff = btrfs_item_offset(leaf, item);
+                       btrfs_set_item_offset(leaf, item, ioff + dsize);
                }
-               memmove(leaf->items + slot, leaf->items + slot + 1,
-                       sizeof(struct btrfs_item) *
-                       (nritems - slot - 1));
+
+               memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot),
+                             btrfs_item_nr_offset(slot + nr),
+                             sizeof(struct btrfs_item) *
+                             (nritems - slot - nr));
        }
-       btrfs_set_header_nritems(&leaf->header, nritems - 1);
-       nritems--;
+       btrfs_set_header_nritems(leaf, nritems - nr);
+       nritems -= nr;
+
        /* delete the leaf if we've emptied it */
        if (nritems == 0) {
-               if (leaf_buf == root->node) {
-                       btrfs_set_header_level(&leaf->header, 0);
-                       BUG_ON(list_empty(&leaf_buf->dirty));
+               if (leaf == root->node) {
+                       btrfs_set_header_level(leaf, 0);
                } else {
-                       clean_tree_block(trans, root, leaf_buf);
-                       wret = del_ptr(trans, root, path, 1, path->slots[1]);
-                       if (wret)
-                               ret = wret;
-                       wret = btrfs_free_extent(trans, root,
-                                                leaf_buf->blocknr, 1, 1);
+                       clean_tree_block(trans, root, leaf);
+                       wret = btrfs_del_leaf(trans, root, path, leaf);
+                       BUG_ON(ret);
                        if (wret)
                                ret = wret;
                }
        } else {
                int used = leaf_space_used(leaf, 0, nritems);
                if (slot == 0) {
-                       wret = fixup_low_keys(trans, root, path,
-                                             &leaf->items[0].key, 1);
-                       if (wret)
-                               ret = wret;
+                       struct btrfs_disk_key disk_key;
+
+                       btrfs_item_key(leaf, &disk_key, 0);
+                       btrfs_fixup_low_keys(root, path, &disk_key, 1);
                }
-               BUG_ON(list_empty(&leaf_buf->dirty));
 
                /* delete the leaf if it is mostly empty */
-               if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) {
+               if (used < BTRFS_LEAF_DATA_SIZE(root->fs_info) / 4) {
                        /* push_leaf_left fixes the path.
                         * make sure the path still points to our leaf
                         * for possible call to del_ptr below
                         */
                        slot = path->slots[1];
-                       leaf_buf->count++;
-                       wret = push_leaf_left(trans, root, path, 1);
-                       if (wret < 0)
+                       extent_buffer_get(leaf);
+
+                       wret = push_leaf_left(trans, root, path, 1, 1);
+                       if (wret < 0 && wret != -ENOSPC)
                                ret = wret;
-                       if (path->nodes[0] == leaf_buf &&
-                           btrfs_header_nritems(&leaf->header)) {
-                               wret = push_leaf_right(trans, root, path, 1);
-                               if (wret < 0)
+
+                       if (path->nodes[0] == leaf &&
+                           btrfs_header_nritems(leaf)) {
+                               wret = push_leaf_right(trans, root, path, 1, 1);
+                               if (wret < 0 && wret != -ENOSPC)
                                        ret = wret;
                        }
-                       if (btrfs_header_nritems(&leaf->header) == 0) {
-                               u64 blocknr = leaf_buf->blocknr;
-                               clean_tree_block(trans, root, leaf_buf);
-                               wret = del_ptr(trans, root, path, 1, slot);
-                               if (wret)
-                                       ret = wret;
-                               btrfs_block_release(root, leaf_buf);
-                               wret = btrfs_free_extent(trans, root, blocknr,
-                                                        1, 1);
-                               if (wret)
-                                       ret = wret;
+
+                       if (btrfs_header_nritems(leaf) == 0) {
+                               clean_tree_block(trans, root, leaf);
+                               path->slots[1] = slot;
+                               ret = btrfs_del_leaf(trans, root, path, leaf);
+                               BUG_ON(ret);
+                               free_extent_buffer(leaf);
+
                        } else {
-                               btrfs_block_release(root, leaf_buf);
+                               btrfs_mark_buffer_dirty(leaf);
+                               free_extent_buffer(leaf);
                        }
+               } else {
+                       btrfs_mark_buffer_dirty(leaf);
                }
        }
        return ret;
 }
 
-int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root
-                     *root, struct btrfs_path *path, u32 data_size)
+/*
+ * walk up the tree as far as required to find the previous leaf.
+ * returns 0 if it found something or 1 if there are no lesser leaves.
+ * returns < 0 on io errors.
+ */
+int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
-       int ret = 0;
        int slot;
-       int slot_orig;
-       struct btrfs_leaf *leaf;
-       struct btrfs_buffer *leaf_buf;
-       u32 nritems;
-       unsigned int data_end;
-       unsigned int old_data;
-       unsigned int old_size;
-       int i;
-
-       slot_orig = path->slots[0];
-       leaf_buf = path->nodes[0];
-       leaf = &leaf_buf->leaf;
-
-       nritems = btrfs_header_nritems(&leaf->header);
-       data_end = leaf_data_end(root, leaf);
+       int level = 1;
+       struct extent_buffer *c;
+       struct extent_buffer *next = NULL;
+       struct btrfs_fs_info *fs_info = root->fs_info;
 
-       if (btrfs_leaf_free_space(root, leaf) < data_size)
-               BUG();
-       slot = path->slots[0];
-       old_data = btrfs_item_end(leaf->items + slot);
+       while(level < BTRFS_MAX_LEVEL) {
+               if (!path->nodes[level])
+                       return 1;
 
-       BUG_ON(slot < 0);
-       BUG_ON(slot >= nritems);
+               slot = path->slots[level];
+               c = path->nodes[level];
+               if (slot == 0) {
+                       level++;
+                       if (level == BTRFS_MAX_LEVEL)
+                               return 1;
+                       continue;
+               }
+               slot--;
 
-       /*
-        * item0..itemN ... dataN.offset..dataN.size .. data0.size
-        */
-       /* first correct the data pointers */
-       for (i = slot; i < nritems; i++) {
-               u32 ioff = btrfs_item_offset(leaf->items + i);
-               btrfs_set_item_offset(leaf->items + i,
-                                     ioff - data_size);
+               next = read_node_slot(fs_info, c, slot);
+               if (!extent_buffer_uptodate(next)) {
+                       if (IS_ERR(next))
+                               return PTR_ERR(next);
+                       return -EIO;
+               }
+               break;
        }
-       /* shift the data */
-       memmove(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(leaf->items + slot);
-       btrfs_set_item_size(leaf->items + slot, old_size + data_size);
-
-       ret = 0;
-       if (btrfs_leaf_free_space(root, leaf) < 0)
-               BUG();
-       check_leaf(root, path, 0);
-       return ret;
+       path->slots[level] = slot;
+       while(1) {
+               level--;
+               c = path->nodes[level];
+               free_extent_buffer(c);
+               slot = btrfs_header_nritems(next);
+               if (slot != 0)
+                       slot--;
+               path->nodes[level] = next;
+               path->slots[level] = slot;
+               if (!level)
+                       break;
+               next = read_node_slot(fs_info, next, slot);
+               if (!extent_buffer_uptodate(next)) {
+                       if (IS_ERR(next))
+                               return PTR_ERR(next);
+                       return -EIO;
+               }
+       }
+       return 0;
 }
 
 /*
@@ -1433,36 +2854,147 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 {
        int slot;
        int level = 1;
-       u64 blocknr;
-       struct btrfs_buffer *c;
-       struct btrfs_buffer *next = NULL;
+       struct extent_buffer *c;
+       struct extent_buffer *next = NULL;
+       struct btrfs_fs_info *fs_info = root->fs_info;
 
        while(level < BTRFS_MAX_LEVEL) {
                if (!path->nodes[level])
                        return 1;
+
                slot = path->slots[level] + 1;
                c = path->nodes[level];
-               if (slot >= btrfs_header_nritems(&c->node.header)) {
+               if (slot >= btrfs_header_nritems(c)) {
                        level++;
+                       if (level == BTRFS_MAX_LEVEL)
+                               return 1;
                        continue;
                }
-               blocknr = btrfs_node_blockptr(&c->node, slot);
-               if (next)
-                       btrfs_block_release(root, next);
-               next = read_tree_block(root, blocknr);
+
+               if (path->reada)
+                       reada_for_search(root, path, level, slot, 0);
+
+               next = read_node_slot(fs_info, c, slot);
+               if (!extent_buffer_uptodate(next))
+                       return -EIO;
                break;
        }
        path->slots[level] = slot;
        while(1) {
                level--;
                c = path->nodes[level];
-               btrfs_block_release(root, c);
+               free_extent_buffer(c);
                path->nodes[level] = next;
                path->slots[level] = 0;
                if (!level)
                        break;
-               next = read_tree_block(root,
-                                      btrfs_node_blockptr(&next->node, 0));
+               if (path->reada)
+                       reada_for_search(root, path, level, 0, 0);
+               next = read_node_slot(fs_info, next, 0);
+               if (!extent_buffer_uptodate(next))
+                       return -EIO;
        }
        return 0;
 }
+
+int btrfs_previous_item(struct btrfs_root *root,
+                       struct btrfs_path *path, u64 min_objectid,
+                       int type)
+{
+       struct btrfs_key found_key;
+       struct extent_buffer *leaf;
+       u32 nritems;
+       int ret;
+
+       while(1) {
+               if (path->slots[0] == 0) {
+                       ret = btrfs_prev_leaf(root, path);
+                       if (ret != 0)
+                               return ret;
+               } else {
+                       path->slots[0]--;
+               }
+               leaf = path->nodes[0];
+               nritems = btrfs_header_nritems(leaf);
+               if (nritems == 0)
+                       return 1;
+               if (path->slots[0] == nritems)
+                       path->slots[0]--;
+
+               btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+               if (found_key.objectid < min_objectid)
+                       break;
+               if (found_key.type == type)
+                       return 0;
+               if (found_key.objectid == min_objectid &&
+                   found_key.type < type)
+                       break;
+       }
+       return 1;
+}
+
+/*
+ * search in extent tree to find a previous Metadata/Data extent item with
+ * min objecitd.
+ *
+ * returns 0 if something is found, 1 if nothing was found and < 0 on error
+ */
+int btrfs_previous_extent_item(struct btrfs_root *root,
+                       struct btrfs_path *path, u64 min_objectid)
+{
+       struct btrfs_key found_key;
+       struct extent_buffer *leaf;
+       u32 nritems;
+       int ret;
+
+       while (1) {
+               if (path->slots[0] == 0) {
+                       ret = btrfs_prev_leaf(root, path);
+                       if (ret != 0)
+                               return ret;
+               } else {
+                       path->slots[0]--;
+               }
+               leaf = path->nodes[0];
+               nritems = btrfs_header_nritems(leaf);
+               if (nritems == 0)
+                       return 1;
+               if (path->slots[0] == nritems)
+                       path->slots[0]--;
+
+               btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+               if (found_key.objectid < min_objectid)
+                       break;
+               if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+                   found_key.type == BTRFS_METADATA_ITEM_KEY)
+                       return 0;
+               if (found_key.objectid == min_objectid &&
+                   found_key.type < BTRFS_EXTENT_ITEM_KEY)
+                       break;
+       }
+       return 1;
+}
+
+/*
+ * Search in extent tree to found next meta/data extent
+ * Caller needs to check for no-hole or skinny metadata features.
+ */
+int btrfs_next_extent_item(struct btrfs_root *root,
+                       struct btrfs_path *path, u64 max_objectid)
+{
+       struct btrfs_key found_key;
+       int ret;
+
+       while (1) {
+               ret = btrfs_next_item(root, path);
+               if (ret)
+                       return ret;
+               btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+                                     path->slots[0]);
+               if (found_key.objectid > max_objectid)
+                       return 1;
+               if (found_key.type == BTRFS_EXTENT_ITEM_KEY ||
+                   found_key.type == BTRFS_METADATA_ITEM_KEY)
+               return 0;
+       }
+}