#define BIT_ARRAY_BYTES 256
 #define BIT_RADIX_BITS_PER_ARRAY ((BIT_ARRAY_BYTES - sizeof(unsigned long)) * 8)
 
+extern struct kmem_cache *btrfs_bit_radix_cachep;
 int set_radix_bit(struct radix_tree_root *radix, unsigned long bit)
 {
        unsigned long *bits;
 
        bits = radix_tree_lookup(radix, slot);
        if (!bits) {
-               bits = kmalloc(BIT_ARRAY_BYTES, GFP_NOFS);
+               bits = kmem_cache_alloc(btrfs_bit_radix_cachep, GFP_NOFS);
                if (!bits)
                        return -ENOMEM;
                memset(bits + 1, 0, BIT_ARRAY_BYTES - sizeof(unsigned long));
                        break;
                }
        }
-
        if (empty) {
                bits = radix_tree_delete(radix, slot);
-               synchronize_rcu();
                BUG_ON(!bits);
-               kfree(bits);
+               kmem_cache_free(btrfs_bit_radix_cachep, bits);
        }
 #endif
        return 0;
 
--- /dev/null
+#ifndef __BTRFS_I__
+#define __BTRFS_I__
+
+struct btrfs_inode {
+       u32 magic;
+       struct inode vfs_inode;
+       u32 magic2;
+};
+static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
+{
+       return container_of(inode, struct btrfs_inode, vfs_inode);
+}
+
+#endif
 
 static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                   struct btrfs_path *path, int level, int slot);
 
+struct btrfs_path *btrfs_alloc_path(void)
+{
+       return kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS);
+}
+
+void btrfs_free_path(struct btrfs_path *p)
+{
+       kmem_cache_free(btrfs_path_cachep, p);
+}
+
 inline void btrfs_init_path(struct btrfs_path *p)
 {
        memset(p, 0, sizeof(*p));
        }
        cow = btrfs_alloc_free_block(trans, root);
        cow_node = btrfs_buffer_node(cow);
+       if (buf->b_size != root->blocksize || cow->b_size != root->blocksize)
+               WARN_ON(1);
        memcpy(cow_node, btrfs_buffer_node(buf), root->blocksize);
        btrfs_set_header_blocknr(&cow_node->header, cow->b_blocknr);
        btrfs_set_header_generation(&cow_node->header, trans->transid);
-       *cow_ret = cow;
-       btrfs_mark_buffer_dirty(cow);
        btrfs_inc_ref(trans, root, buf);
        if (buf == root->node) {
                root->node = cow;
                get_bh(cow);
-               if (buf != root->commit_root)
+               if (buf != root->commit_root) {
                        btrfs_free_extent(trans, root, buf->b_blocknr, 1, 1);
+               }
                btrfs_block_release(root, buf);
        } else {
                btrfs_set_node_blockptr(btrfs_buffer_node(parent), parent_slot,
                btrfs_free_extent(trans, root, buf->b_blocknr, 1, 1);
        }
        btrfs_block_release(root, buf);
+       *cow_ret = cow;
        return 0;
 }
 
                                               p->slots[level + 1],
                                               &cow_buf);
                        b = cow_buf;
+                       c = btrfs_buffer_node(b);
                }
                BUG_ON(!cow && ins_len);
-               c = btrfs_buffer_node(b);
+               if (level != btrfs_header_level(&c->header))
+                       WARN_ON(1);
+               level = btrfs_header_level(&c->header);
                p->nodes[level] = b;
                ret = check_block(root, p, level);
                if (ret)
                      data_size)
 {
        int ret = 0;
-       struct btrfs_path path;
+       struct btrfs_path *path;
        u8 *ptr;
 
-       btrfs_init_path(&path);
-       ret = btrfs_insert_empty_item(trans, root, &path, cpu_key, data_size);
+       path = btrfs_alloc_path();
+       BUG_ON(!path);
+       btrfs_init_path(path);
+       ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
        if (!ret) {
-               ptr = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
-                                    path.slots[0], u8);
-               btrfs_memcpy(root, path.nodes[0]->b_data,
+               ptr = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+                                    path->slots[0], u8);
+               btrfs_memcpy(root, path->nodes[0]->b_data,
                             ptr, data, data_size);
-               btrfs_mark_buffer_dirty(path.nodes[0]);
+               btrfs_mark_buffer_dirty(path->nodes[0]);
        }
-       btrfs_release_path(root, &path);
+       btrfs_release_path(root, path);
+       btrfs_free_path(path);
        return ret;
 }
 
 
 
 struct btrfs_trans_handle;
 struct btrfs_transaction;
+extern struct kmem_cache *btrfs_path_cachep;
 
 #define BTRFS_MAGIC "_BtRfS_M"
 
                      *root, struct btrfs_key *key, struct btrfs_path *p, int
                      ins_len, int cow);
 void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
+struct btrfs_path *btrfs_alloc_path(void);
+void btrfs_free_path(struct btrfs_path *p);
 void btrfs_init_path(struct btrfs_path *p);
 int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                   struct btrfs_path *path);
 
 #include "disk-io.h"
 #include "transaction.h"
 
-#define PATTERN 0xDEADBEEFUL
-static inline void check_pattern(struct buffer_head *buf)
-{
-       if (buf->b_private != (void *)PATTERN)
-               WARN_ON(1);
-}
-
-static inline void set_pattern(struct buffer_head *buf)
-{
-       buf->b_private = (void *)PATTERN;
-}
-
 static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
 {
        struct btrfs_node *node = btrfs_buffer_node(buf);
 
 struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr)
 {
+       return sb_find_get_block(root->fs_info->sb, blocknr);
+#if 0
        struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
        int blockbits = root->fs_info->sb->s_blocksize_bits;
        unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
        struct buffer_head *head;
        struct buffer_head *ret = NULL;
 
+
        page = find_lock_page(mapping, index);
        if (!page)
                return NULL;
        unlock_page(page);
        if (ret) {
                touch_buffer(ret);
-               check_pattern(ret);
        }
        page_cache_release(page);
        return ret;
+#endif
 }
 
 struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
                                                 u64 blocknr)
 {
+       return sb_getblk(root->fs_info->sb, blocknr);
+#if 0
        struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
        int blockbits = root->fs_info->sb->s_blocksize_bits;
        unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
                        bh->b_bdev = root->fs_info->sb->s_bdev;
                        bh->b_blocknr = first_block;
                        set_buffer_mapped(bh);
-                       set_pattern(bh);
                }
                if (bh->b_blocknr == blocknr) {
                        ret = bh;
                touch_buffer(ret);
        page_cache_release(page);
        return ret;
+#endif
 }
 
 static sector_t max_block(struct block_device *bdev)
 
 struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
 {
+       return sb_bread(root->fs_info->sb, blocknr);
+#if 0
        struct buffer_head *bh = NULL;
 
        bh = btrfs_find_create_tree_block(root, blocknr);
                if (!buffer_uptodate(bh))
                        goto fail;
                csum_tree_block(root, bh, 1);
-               set_pattern(bh);
        } else {
                unlock_buffer(bh);
        }
        brelse(bh);
        return NULL;
 
+#endif
 }
 
 int dirty_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
        return 0;
 }
 
-static int __setup_root(struct btrfs_super_block *super,
+static int __setup_root(int blocksize,
                        struct btrfs_root *root,
                        struct btrfs_fs_info *fs_info,
                        u64 objectid)
 {
        root->node = NULL;
        root->commit_root = NULL;
-       root->blocksize = btrfs_super_blocksize(super);
+       root->blocksize = blocksize;
        root->ref_cows = 0;
        root->fs_info = fs_info;
        memset(&root->root_key, 0, sizeof(root->root_key));
        return 0;
 }
 
-static int find_and_setup_root(struct btrfs_super_block *super,
+static int find_and_setup_root(int blocksize,
                               struct btrfs_root *tree_root,
                               struct btrfs_fs_info *fs_info,
                               u64 objectid,
 {
        int ret;
 
-       __setup_root(super, root, fs_info, objectid);
+       __setup_root(blocksize, root, fs_info, objectid);
        ret = btrfs_find_last_root(tree_root, objectid,
                                   &root->root_item, &root->root_key);
        BUG_ON(ret);
        return 0;
 }
 
-struct btrfs_root *open_ctree(struct super_block *sb,
-                             struct buffer_head *sb_buffer,
-                             struct btrfs_super_block *disk_super)
+struct btrfs_root *open_ctree(struct super_block *sb)
 {
        struct btrfs_root *root = kmalloc(sizeof(struct btrfs_root),
                                          GFP_NOFS);
        struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
                                                GFP_NOFS);
        int ret;
+       struct btrfs_super_block *disk_super;
 
-       if (!btrfs_super_root(disk_super)) {
-               return NULL;
-       }
        init_bit_radix(&fs_info->pinned_radix);
        init_bit_radix(&fs_info->pending_del_radix);
-       sb_set_blocksize(sb, sb_buffer->b_size);
+       sb_set_blocksize(sb, 4096);
        fs_info->running_transaction = NULL;
        fs_info->fs_root = root;
        fs_info->tree_root = tree_root;
        fs_info->inode_root = inode_root;
        fs_info->last_inode_alloc = 0;
        fs_info->last_inode_alloc_dirid = 0;
-       fs_info->disk_super = disk_super;
        fs_info->sb = sb;
+       fs_info->btree_inode = NULL;
+#if 0
        fs_info->btree_inode = new_inode(sb);
        fs_info->btree_inode->i_ino = 1;
+       fs_info->btree_inode->i_nlink = 1;
        fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
        fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
        insert_inode_hash(fs_info->btree_inode);
-
        mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
+#endif
        fs_info->hash_tfm = crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC);
        spin_lock_init(&fs_info->hash_lock);
-
        if (!fs_info->hash_tfm || IS_ERR(fs_info->hash_tfm)) {
                printk("failed to allocate sha256 hash\n");
                return NULL;
        }
-
        mutex_init(&fs_info->trans_mutex);
        mutex_init(&fs_info->fs_mutex);
        memset(&fs_info->current_insert, 0, sizeof(fs_info->current_insert));
        memset(&fs_info->last_insert, 0, sizeof(fs_info->last_insert));
 
-       __setup_root(disk_super, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID);
-
-       fs_info->sb_buffer = read_tree_block(tree_root, sb_buffer->b_blocknr);
+       __setup_root(sb->s_blocksize, tree_root,
+                    fs_info, BTRFS_ROOT_TREE_OBJECTID);
+       fs_info->sb_buffer = read_tree_block(tree_root,
+                                            BTRFS_SUPER_INFO_OFFSET /
+                                            sb->s_blocksize);
 
        if (!fs_info->sb_buffer) {
 printk("failed2\n");
                return NULL;
        }
-       brelse(sb_buffer);
-       sb_buffer = NULL;
        disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
+       if (!btrfs_super_root(disk_super)) {
+               return NULL;
+       }
        fs_info->disk_super = disk_super;
-
        tree_root->node = read_tree_block(tree_root,
                                          btrfs_super_root(disk_super));
        BUG_ON(!tree_root->node);
 
-       ret = find_and_setup_root(disk_super, tree_root, fs_info,
+       mutex_lock(&fs_info->fs_mutex);
+       ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
                                  BTRFS_EXTENT_TREE_OBJECTID, extent_root);
        BUG_ON(ret);
 
-       ret = find_and_setup_root(disk_super, tree_root, fs_info,
+       ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
                                  BTRFS_INODE_MAP_OBJECTID, inode_root);
        BUG_ON(ret);
 
-       ret = find_and_setup_root(disk_super, tree_root, fs_info,
+       ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
                                  BTRFS_FS_TREE_OBJECTID, root);
+       mutex_unlock(&fs_info->fs_mutex);
        BUG_ON(ret);
        root->commit_root = root->node;
        get_bh(root->node);
                      *root)
 {
        struct buffer_head *bh = root->fs_info->sb_buffer;
+
        btrfs_set_super_root(root->fs_info->disk_super,
                             root->fs_info->tree_root->node->b_blocknr);
        lock_buffer(bh);
+       WARN_ON(atomic_read(&bh->b_count) < 1);
        clear_buffer_dirty(bh);
        csum_tree_block(root, bh, 0);
        bh->b_end_io = end_buffer_write_sync;
        int ret;
        struct btrfs_trans_handle *trans;
 
+       mutex_lock(&root->fs_info->fs_mutex);
        trans = btrfs_start_transaction(root, 1);
        btrfs_commit_transaction(trans, root);
        /* run commit again to  drop the original snapshot */
        ret = btrfs_write_and_wait_transaction(NULL, root);
        BUG_ON(ret);
        write_ctree_super(NULL, root);
+       mutex_unlock(&root->fs_info->fs_mutex);
 
        if (root->node)
                btrfs_block_release(root, root->node);
        btrfs_block_release(root, root->commit_root);
        btrfs_block_release(root, root->fs_info->sb_buffer);
        crypto_free_hash(root->fs_info->hash_tfm);
-       truncate_inode_pages(root->fs_info->btree_inode->i_mapping, 0);
-       iput(root->fs_info->btree_inode);
+       // truncate_inode_pages(root->fs_info->btree_inode->i_mapping, 0);
+       // iput(root->fs_info->btree_inode);
        kfree(root->fs_info->extent_root);
        kfree(root->fs_info->inode_root);
        kfree(root->fs_info->tree_root);
 
 void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf)
 {
-       check_pattern(buf);
-       brelse(buf);
+       // brelse(buf);
 }
 
 
                     struct btrfs_root *root, struct buffer_head *buf);
 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                             struct btrfs_root *root);
-struct btrfs_root *open_ctree(struct super_block *sb,
-                             struct buffer_head *sb_buffer,
-                             struct btrfs_super_block *disk_super);
+struct btrfs_root *open_ctree(struct super_block *sb);
 int close_ctree(struct btrfs_root *root);
 void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf);
 int write_ctree_super(struct btrfs_trans_handle *trans,
 
 
        if (!pending) {
                bh = btrfs_find_tree_block(root, blocknr);
-               if (bh && buffer_uptodate(bh)) {
-                       header = btrfs_buffer_header(bh);
-                       if (btrfs_header_generation(header) ==
-                           root->fs_info->running_transaction->transid) {
-                               btrfs_block_release(root, bh);
-                               return 0;
+               if (bh) {
+                       if (buffer_uptodate(bh)) {
+                               u64 transid =
+                                   root->fs_info->running_transaction->transid;
+                               header = btrfs_buffer_header(bh);
+                               if (btrfs_header_generation(header) ==
+                                   transid) {
+                                       btrfs_block_release(root, bh);
+                                       return 0;
+                               }
                        }
                        btrfs_block_release(root, bh);
                }
         */
        while(*level >= 0) {
                cur = path->nodes[*level];
+               if (btrfs_header_level(btrfs_buffer_header(cur)) != *level)
+                       WARN_ON(1);
                if (path->slots[*level] >=
                    btrfs_header_nritems(btrfs_buffer_header(cur)))
                        break;
 
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
+#include "btrfs_inode.h"
 
 #define BTRFS_SUPER_MAGIC 0x9123682E
 
 static struct address_space_operations btrfs_aops;
 static struct file_operations btrfs_file_operations;
 
+static int check_inode(struct inode *inode)
+{
+       struct btrfs_inode *ei = BTRFS_I(inode);
+       WARN_ON(ei->magic != 0xDEADBEEF);
+       WARN_ON(ei->magic2 != 0xDEADBEAF);
+       return 0;
+}
+
 static void btrfs_read_locked_inode(struct inode *inode)
 {
        struct btrfs_path path;
        btrfs_init_path(&path);
        mutex_lock(&root->fs_info->fs_mutex);
 
+       check_inode(inode);
        ret = btrfs_lookup_inode(NULL, root, &path, inode->i_ino, 0);
        if (ret) {
                btrfs_release_path(root, &path);
                make_bad_inode(inode);
                return;
        }
+       check_inode(inode);
        inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]),
                                  path.slots[0],
                                  struct btrfs_inode_item);
        inode->i_generation = btrfs_inode_generation(inode_item);
        btrfs_release_path(root, &path);
        mutex_unlock(&root->fs_info->fs_mutex);
+       check_inode(inode);
        switch (inode->i_mode & S_IFMT) {
 #if 0
        default:
                // inode->i_op = &page_symlink_inode_operations;
                break;
        }
+       check_inode(inode);
        return;
 }
 
                                    namelen, 0);
        if (ret || !btrfs_match_dir_item_name(root, &path, name, namelen)) {
                *ino = 0;
+               ret = 0;
                goto out;
        }
        di = btrfs_item_ptr(btrfs_buffer_leaf(path.nodes[0]), path.slots[0],
        *ino = btrfs_dir_objectid(di);
 out:
        btrfs_release_path(root, &path);
+       check_inode(dir);
        return ret;
 }
 
 
        if (dentry->d_name.len > BTRFS_NAME_LEN)
                return ERR_PTR(-ENAMETOOLONG);
-
        mutex_lock(&root->fs_info->fs_mutex);
        ret = btrfs_inode_by_name(dir, dentry, &ino);
        mutex_unlock(&root->fs_info->fs_mutex);
                inode = iget(dir->i_sb, ino);
                if (!inode)
                        return ERR_PTR(-EACCES);
+               check_inode(inode);
        }
+       check_inode(dir);
        return d_splice_alias(inode, dentry);
 }
 
        struct inode * inode;
        struct dentry * root_dentry;
        struct btrfs_super_block *disk_super;
-       struct buffer_head *bh;
        struct btrfs_root *root;
 
        sb->s_maxbytes = MAX_LFS_FILESIZE;
-       sb->s_blocksize = PAGE_CACHE_SIZE;
-       sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
        sb->s_magic = BTRFS_SUPER_MAGIC;
        sb->s_op = &btrfs_super_ops;
        sb->s_time_gran = 1;
 
-       bh = sb_bread(sb, BTRFS_SUPER_INFO_OFFSET / sb->s_blocksize);
-       if (!bh) {
-               printk("btrfs: unable to read on disk super\n");
-               return -EIO;
-       }
-       disk_super = (struct btrfs_super_block *)bh->b_data;
-       root = open_ctree(sb, bh, disk_super);
+       root = open_ctree(sb);
 
        if (!root) {
                printk("btrfs: open_ctree failed\n");
        btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
        btrfs_set_inode_nblocks(item, inode->i_blocks);
        btrfs_set_inode_generation(item, inode->i_generation);
+       check_inode(inode);
 }
 
 static int btrfs_update_inode(struct btrfs_trans_handle *trans,
        btrfs_mark_buffer_dirty(path.nodes[0]);
 failed:
        btrfs_release_path(root, &path);
+       check_inode(inode);
        return 0;
 }
 
        else
                btrfs_end_transaction(trans, root);
        mutex_unlock(&root->fs_info->fs_mutex);
+       check_inode(inode);
        return ret;
 }
 
        if (!inode)
                return ERR_PTR(-ENOMEM);
 
+       check_inode(inode);
        ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
        BUG_ON(ret);
 
        BUG_ON(ret);
 
        insert_inode_hash(inode);
+       check_inode(inode);
+       check_inode(dir);
        return inode;
 }
 
                ret = btrfs_update_inode(trans, btrfs_sb(inode->i_sb),
                                         dentry->d_parent->d_inode);
        }
-
+       check_inode(inode);
+       check_inode(dentry->d_parent->d_inode);
        return ret;
 }
 
                d_instantiate(dentry, inode);
                return 0;
        }
+       if (err > 0)
+               err = -EEXIST;
+       check_inode(inode);
        return err;
 }
 
 out_unlock:
        btrfs_end_transaction(trans, root);
        mutex_unlock(&root->fs_info->fs_mutex);
+       check_inode(inode);
+       check_inode(dir);
+
        if (drop_inode) {
                inode_dec_link_count(inode);
                iput(inode);
 
        sb->s_dirt = 0;
        if (!wait) {
-               filemap_flush(root->fs_info->btree_inode->i_mapping);
+               // filemap_flush(root->fs_info->btree_inode->i_mapping);
+               filemap_flush(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
                return 0;
        }
-       filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
-
+       filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
        mutex_lock(&root->fs_info->fs_mutex);
        trans = btrfs_start_transaction(root, 1);
        ret = btrfs_commit_transaction(trans, root);
        return retval;
 }
 
+static struct kmem_cache *btrfs_inode_cachep;
+struct kmem_cache *btrfs_trans_handle_cachep;
+struct kmem_cache *btrfs_transaction_cachep;
+struct kmem_cache *btrfs_bit_radix_cachep;
+struct kmem_cache *btrfs_path_cachep;
+
+/*
+ * Called inside transaction, so use GFP_NOFS
+ */
+static struct inode *btrfs_alloc_inode(struct super_block *sb)
+{
+       struct btrfs_inode *ei;
+
+       ei = kmem_cache_alloc(btrfs_inode_cachep, GFP_NOFS);
+       if (!ei)
+               return NULL;
+       ei->magic = 0xDEADBEEF;
+       ei->magic2 = 0xDEADBEAF;
+       return &ei->vfs_inode;
+}
+
+static void btrfs_destroy_inode(struct inode *inode)
+{
+       struct btrfs_inode *ei = BTRFS_I(inode);
+       WARN_ON(ei->magic != 0xDEADBEEF);
+       WARN_ON(ei->magic2 != 0xDEADBEAF);
+       WARN_ON(!list_empty(&inode->i_dentry));
+       WARN_ON(inode->i_ino == 1);
+       WARN_ON(inode->i_data.nrpages);
+
+       ei->magic = 0;
+       ei->magic2 = 0;
+       kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
+}
+
+static void init_once(void * foo, struct kmem_cache * cachep,
+                     unsigned long flags)
+{
+       struct btrfs_inode *ei = (struct btrfs_inode *) foo;
+
+       if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+           SLAB_CTOR_CONSTRUCTOR) {
+               inode_init_once(&ei->vfs_inode);
+       }
+}
+
+static int init_inodecache(void)
+{
+       btrfs_inode_cachep = kmem_cache_create("btrfs_inode_cache",
+                                            sizeof(struct btrfs_inode),
+                                            0, (SLAB_RECLAIM_ACCOUNT|
+                                               SLAB_MEM_SPREAD),
+                                            init_once, NULL);
+       btrfs_trans_handle_cachep = kmem_cache_create("btrfs_trans_handle_cache",
+                                            sizeof(struct btrfs_trans_handle),
+                                            0, (SLAB_RECLAIM_ACCOUNT|
+                                               SLAB_MEM_SPREAD),
+                                            NULL, NULL);
+       btrfs_transaction_cachep = kmem_cache_create("btrfs_transaction_cache",
+                                            sizeof(struct btrfs_transaction),
+                                            0, (SLAB_RECLAIM_ACCOUNT|
+                                               SLAB_MEM_SPREAD),
+                                            NULL, NULL);
+       btrfs_path_cachep = kmem_cache_create("btrfs_path_cache",
+                                            sizeof(struct btrfs_transaction),
+                                            0, (SLAB_RECLAIM_ACCOUNT|
+                                               SLAB_MEM_SPREAD),
+                                            NULL, NULL);
+       btrfs_bit_radix_cachep = kmem_cache_create("btrfs_radix",
+                                            256,
+                                            0, (SLAB_RECLAIM_ACCOUNT|
+                                               SLAB_MEM_SPREAD |
+                                               SLAB_DESTROY_BY_RCU),
+                                            NULL, NULL);
+       if (btrfs_inode_cachep == NULL || btrfs_trans_handle_cachep == NULL ||
+           btrfs_transaction_cachep == NULL || btrfs_bit_radix_cachep == NULL)
+               return -ENOMEM;
+       return 0;
+}
+
+static void destroy_inodecache(void)
+{
+       kmem_cache_destroy(btrfs_inode_cachep);
+       kmem_cache_destroy(btrfs_trans_handle_cachep);
+       kmem_cache_destroy(btrfs_transaction_cachep);
+       kmem_cache_destroy(btrfs_bit_radix_cachep);
+       kmem_cache_destroy(btrfs_path_cachep);
+}
+
 static int btrfs_get_sb(struct file_system_type *fs_type,
        int flags, const char *dev_name, void *data, struct vfsmount *mnt)
 {
        .write_super    = btrfs_write_super,
        .sync_fs        = btrfs_sync_fs,
        .write_inode    = btrfs_write_inode,
+       .alloc_inode    = btrfs_alloc_inode,
+       .destroy_inode  = btrfs_destroy_inode,
 };
 
 static struct inode_operations btrfs_dir_inode_operations = {
 
 static int __init init_btrfs_fs(void)
 {
+       int err;
        printk("btrfs loaded!\n");
+       err = init_inodecache();
+       if (err)
+               return err;
        return register_filesystem(&btrfs_fs_type);
 }
 
 static void __exit exit_btrfs_fs(void)
 {
+       destroy_inodecache();
        unregister_filesystem(&btrfs_fs_type);
        printk("btrfs unloaded\n");
 }
 
 #include "transaction.h"
 
 static int total_trans = 0;
+extern struct kmem_cache *btrfs_trans_handle_cachep;
+extern struct kmem_cache *btrfs_transaction_cachep;
+
+#define TRANS_MAGIC 0xE1E10E
 static void put_transaction(struct btrfs_transaction *transaction)
 {
+       WARN_ON(transaction->use_count == 0);
        transaction->use_count--;
+       WARN_ON(transaction->magic != TRANS_MAGIC);
        if (transaction->use_count == 0) {
                WARN_ON(total_trans == 0);
                total_trans--;
-               kfree(transaction);
+               memset(transaction, 0, sizeof(*transaction));
+               kmem_cache_free(btrfs_transaction_cachep, transaction);
        }
 }
 
        struct btrfs_transaction *cur_trans;
        cur_trans = root->fs_info->running_transaction;
        if (!cur_trans) {
-               cur_trans = kmalloc(sizeof(*cur_trans), GFP_NOFS);
+               cur_trans = kmem_cache_alloc(btrfs_transaction_cachep,
+                                            GFP_NOFS);
                total_trans++;
                BUG_ON(!cur_trans);
                root->fs_info->running_transaction = cur_trans;
                cur_trans->transid = root->root_key.offset + 1;
                init_waitqueue_head(&cur_trans->writer_wait);
                init_waitqueue_head(&cur_trans->commit_wait);
+               cur_trans->magic = TRANS_MAGIC;
                cur_trans->in_commit = 0;
                cur_trans->use_count = 1;
                cur_trans->commit_done = 0;
 struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
                                                   int num_blocks)
 {
-       struct btrfs_trans_handle *h = kmalloc(sizeof(*h), GFP_NOFS);
+       struct btrfs_trans_handle *h =
+               kmem_cache_alloc(btrfs_trans_handle_cachep, GFP_NOFS);
        int ret;
 
        mutex_lock(&root->fs_info->trans_mutex);
        h->blocks_used = 0;
        root->fs_info->running_transaction->use_count++;
        mutex_unlock(&root->fs_info->trans_mutex);
+       h->magic = h->magic2 = TRANS_MAGIC;
        return h;
 }
 
                          struct btrfs_root *root)
 {
        struct btrfs_transaction *cur_trans;
+       WARN_ON(trans->magic != TRANS_MAGIC);
+       WARN_ON(trans->magic2 != TRANS_MAGIC);
        mutex_lock(&root->fs_info->trans_mutex);
        cur_trans = root->fs_info->running_transaction;
        WARN_ON(cur_trans->num_writers < 1);
        put_transaction(cur_trans);
        mutex_unlock(&root->fs_info->trans_mutex);
        memset(trans, 0, sizeof(*trans));
-       kfree(trans);
+       kmem_cache_free(btrfs_trans_handle_cachep, trans);
        return 0;
 }
 
 int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans,
                                     struct btrfs_root *root)
 {
-       filemap_write_and_wait(root->fs_info->btree_inode->i_mapping);
+       filemap_write_and_wait(root->fs_info->sb->s_bdev->bd_inode->i_mapping);
        return 0;
 }
 
 
        mutex_lock(&root->fs_info->trans_mutex);
        if (trans->transaction->in_commit) {
+printk("already in commit!, waiting\n");
                cur_trans = trans->transaction;
                trans->transaction->use_count++;
                btrfs_end_transaction(trans, root);
                mutex_unlock(&root->fs_info->trans_mutex);
                return 0;
        }
+       cur_trans = trans->transaction;
+       trans->transaction->in_commit = 1;
        while (trans->transaction->num_writers > 1) {
+               WARN_ON(cur_trans != trans->transaction);
                prepare_to_wait(&trans->transaction->writer_wait, &wait,
                                TASK_UNINTERRUPTIBLE);
                if (trans->transaction->num_writers <= 1)
                mutex_unlock(&root->fs_info->trans_mutex);
                schedule();
                mutex_lock(&root->fs_info->trans_mutex);
+               finish_wait(&trans->transaction->writer_wait, &wait);
        }
        finish_wait(&trans->transaction->writer_wait, &wait);
-
+       WARN_ON(cur_trans != trans->transaction);
        if (root->node != root->commit_root) {
                memcpy(&snap_key, &root->root_key, sizeof(snap_key));
                root->root_key.offset++;
        }
 
-
        if (btrfs_root_blocknr(&root->root_item) != root->node->b_blocknr) {
                btrfs_set_root_blocknr(&root->root_item, root->node->b_blocknr);
                ret = btrfs_insert_root(trans, root->fs_info->tree_root,
 
        ret = btrfs_commit_tree_roots(trans, root);
        BUG_ON(ret);
-
        cur_trans = root->fs_info->running_transaction;
        root->fs_info->running_transaction = NULL;
        mutex_unlock(&root->fs_info->trans_mutex);
-
        ret = btrfs_write_and_wait_transaction(trans, root);
        BUG_ON(ret);
 
        write_ctree_super(trans, root);
        btrfs_finish_extent_commit(trans, root);
        mutex_lock(&root->fs_info->trans_mutex);
+       cur_trans->commit_done = 1;
+       wake_up(&cur_trans->commit_wait);
        put_transaction(cur_trans);
        put_transaction(cur_trans);
        mutex_unlock(&root->fs_info->trans_mutex);
-       kfree(trans);
-
+       kmem_cache_free(btrfs_trans_handle_cachep, trans);
        if (root->node != root->commit_root) {
                trans = btrfs_start_transaction(root, 1);
                snap = root->commit_root;
                ret = btrfs_end_transaction(trans, root);
                BUG_ON(ret);
        }
-
        return ret;
 }
 
 
        int in_commit;
        int use_count;
        int commit_done;
+       int magic;
        wait_queue_head_t writer_wait;
        wait_queue_head_t commit_wait;
 };
 
 struct btrfs_trans_handle {
+       int magic;
        u64 transid;
        unsigned long blocks_reserved;
        unsigned long blocks_used;
        struct btrfs_transaction *transaction;
+       int magic2;
 };