X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=fs%2Fbtrfs%2Fsuper.c;h=43f081593c453beba92527ecf6bc6df6deeaf365;hb=b51338628f604d9b4ed3c776839a484a30e12fb7;hp=68127b8462abca96f1caab00eb1c7cd5c456f3f7;hpb=df24a2b9c9bcef3348e4b1a8f206cd484a248d36;p=deliverable%2Flinux.git

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 68127b8462ab..43f081593c45 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -11,33 +11,47 @@
 #include <linux/mpage.h>
 #include <linux/swap.h>
 #include <linux/writeback.h>
+#include <linux/statfs.h>
 #include "ctree.h"
 #include "disk-io.h"
 #include "transaction.h"
 #include "btrfs_inode.h"
+#include "ioctl.h"
+
+void btrfs_fsinfo_release(struct kobject *obj)
+{
+	struct btrfs_fs_info *fsinfo = container_of(obj,
+					    struct btrfs_fs_info, kobj);
+	kfree(fsinfo);
+}
+
+struct kobj_type btrfs_fsinfo_ktype = {
+	.release = btrfs_fsinfo_release,
+};
+
+struct btrfs_iget_args {
+	u64 ino;
+	struct btrfs_root *root;
+};
+
+decl_subsys(btrfs, &btrfs_fsinfo_ktype, NULL);
 
 #define BTRFS_SUPER_MAGIC 0x9123682E
 
 static struct inode_operations btrfs_dir_inode_operations;
+static struct inode_operations btrfs_dir_ro_inode_operations;
 static struct super_operations btrfs_super_ops;
 static struct file_operations btrfs_dir_file_operations;
 static struct inode_operations btrfs_file_inode_operations;
 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;
 	struct btrfs_inode_item *inode_item;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct btrfs_key location;
 	int ret;
 
 	path = btrfs_alloc_path();
@@ -45,16 +59,12 @@ static void btrfs_read_locked_inode(struct inode *inode)
 	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);
+	memcpy(&location, &BTRFS_I(inode)->location, sizeof(location));
+	ret = btrfs_lookup_inode(NULL, root, path, &location, 0);
 	if (ret) {
-		btrfs_release_path(root, path);
 		btrfs_free_path(path);
-		mutex_unlock(&root->fs_info->fs_mutex);
-		make_bad_inode(inode);
-		return;
+		goto make_bad;
 	}
-	check_inode(inode);
 	inode_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
 				  path->slots[0],
 				  struct btrfs_inode_item);
@@ -73,12 +83,11 @@ static void btrfs_read_locked_inode(struct inode *inode)
 	inode->i_blocks = btrfs_inode_nblocks(inode_item);
 	inode->i_generation = btrfs_inode_generation(inode_item);
 
-	btrfs_release_path(root, path);
 	btrfs_free_path(path);
 	inode_item = NULL;
 
 	mutex_unlock(&root->fs_info->fs_mutex);
-	check_inode(inode);
+
 	switch (inode->i_mode & S_IFMT) {
 #if 0
 	default:
@@ -92,15 +101,23 @@ static void btrfs_read_locked_inode(struct inode *inode)
 		inode->i_op = &btrfs_file_inode_operations;
 		break;
 	case S_IFDIR:
-		inode->i_op = &btrfs_dir_inode_operations;
 		inode->i_fop = &btrfs_dir_file_operations;
+		if (root == root->fs_info->tree_root)
+			inode->i_op = &btrfs_dir_ro_inode_operations;
+		else
+			inode->i_op = &btrfs_dir_inode_operations;
 		break;
 	case S_IFLNK:
 		// inode->i_op = &page_symlink_inode_operations;
 		break;
 	}
-	check_inode(inode);
 	return;
+
+make_bad:
+	btrfs_release_path(root, path);
+	btrfs_free_path(path);
+	mutex_unlock(&root->fs_info->fs_mutex);
+	make_bad_inode(inode);
 }
 
 static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
@@ -111,33 +128,49 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
 	struct btrfs_path *path;
 	const char *name = dentry->d_name.name;
 	int name_len = dentry->d_name.len;
-	int ret;
+	int ret = 0;
 	u64 objectid;
 	struct btrfs_dir_item *di;
 
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 	btrfs_init_path(path);
-	ret = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
+	di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
 				    name, name_len, -1);
-	if (ret < 0)
+	if (IS_ERR(di)) {
+		ret = PTR_ERR(di);
 		goto err;
-	if (ret > 0) {
+	}
+	if (!di) {
 		ret = -ENOENT;
 		goto err;
 	}
-	di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
-			    struct btrfs_dir_item);
-	objectid = btrfs_dir_objectid(di);
+	objectid = btrfs_disk_key_objectid(&di->location);
+	ret = btrfs_delete_one_dir_name(trans, root, path, di);
+	BUG_ON(ret);
+	btrfs_release_path(root, path);
 
-	ret = btrfs_del_item(trans, root, path);
+	di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
+					 objectid, name, name_len, -1);
+	if (IS_ERR(di)) {
+		ret = PTR_ERR(di);
+		goto err;
+	}
+	if (!di) {
+		ret = -ENOENT;
+		goto err;
+	}
+	ret = btrfs_delete_one_dir_name(trans, root, path, di);
 	BUG_ON(ret);
+
 	dentry->d_inode->i_ctime = dir->i_ctime;
 err:
-	btrfs_release_path(root, path);
 	btrfs_free_path(path);
-	if (ret == 0)
+	if (ret == 0) {
 		inode_dec_link_count(dentry->d_inode);
+		dir->i_size -= name_len * 2;
+		mark_inode_dirty(dir);
+	}
 	return ret;
 }
 
@@ -147,7 +180,7 @@ static int btrfs_unlink(struct inode *dir, struct dentry *dentry)
 	struct btrfs_trans_handle *trans;
 	int ret;
 
-	root = btrfs_sb(dir->i_sb);
+	root = BTRFS_I(dir)->root;
 	mutex_lock(&root->fs_info->fs_mutex);
 	trans = btrfs_start_transaction(root, 1);
 	ret = btrfs_unlink_trans(trans, root, dir, dentry);
@@ -161,12 +194,14 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 	struct inode *inode = dentry->d_inode;
 	int err;
 	int ret;
-	struct btrfs_root *root = btrfs_sb(dir->i_sb);
+	struct btrfs_root *root = BTRFS_I(dir)->root;
 	struct btrfs_path *path;
 	struct btrfs_key key;
 	struct btrfs_trans_handle *trans;
-	struct btrfs_disk_key *found_key;
+	struct btrfs_key found_key;
+	int found_type;
 	struct btrfs_leaf *leaf;
+	char *goodnames = "..";
 
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
@@ -175,46 +210,42 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
 	trans = btrfs_start_transaction(root, 1);
 	key.objectid = inode->i_ino;
 	key.offset = (u64)-1;
-	key.flags = 0;
-	btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
-	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
-	if (ret < 0) {
-		err = ret;
-		goto out;
-	}
+	key.flags = (u32)-1;
+	while(1) {
+		ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+		if (ret < 0) {
+			err = ret;
+			goto out;
+		}
+		BUG_ON(ret == 0);
+		if (path->slots[0] == 0) {
+			err = -ENOENT;
+			goto out;
+		}
+		path->slots[0]--;
+		leaf = btrfs_buffer_leaf(path->nodes[0]);
+		btrfs_disk_key_to_cpu(&found_key,
+				      &leaf->items[path->slots[0]].key);
+		found_type = btrfs_key_type(&found_key);
+		if (found_key.objectid != inode->i_ino) {
+			err = -ENOENT;
+			goto out;
+		}
+		if ((found_type != BTRFS_DIR_ITEM_KEY &&
+		     found_type != BTRFS_DIR_INDEX_KEY) ||
+	            (!btrfs_match_dir_item_name(root, path, goodnames, 2) &&
+	            !btrfs_match_dir_item_name(root, path, goodnames, 1))) {
+			err = -ENOTEMPTY;
+			goto out;
+		}
+		ret = btrfs_del_item(trans, root, path);
+		BUG_ON(ret);
 
-	BUG_ON(ret == 0);
-	BUG_ON(path->slots[0] == 0);
-	path->slots[0]--;
-	leaf = btrfs_buffer_leaf(path->nodes[0]);
-	found_key = &leaf->items[path->slots[0]].key;
-	if (btrfs_disk_key_objectid(found_key) != inode->i_ino) {
-		err = -ENOENT;
-		goto out;
-	}
-	if (btrfs_disk_key_type(found_key) != BTRFS_DIR_ITEM_KEY ||
-	    btrfs_disk_key_offset(found_key) != 2) {
-		err = -ENOTEMPTY;
-		goto out;
-	}
-	ret = btrfs_del_item(trans, root, path);
-	BUG_ON(ret);
-	btrfs_release_path(root, path);
-	key.offset = 1;
-	ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
-	if (ret < 0) {
-		err = ret;
-		goto out;
-	}
-	if (ret > 0) {
-		err = -ENOTEMPTY;
-		goto out;
-	}
-	ret = btrfs_del_item(trans, root, path);
-	if (ret) {
-		err = ret;
-		goto out;
+		if (found_type == BTRFS_DIR_ITEM_KEY && found_key.offset == 1)
+			break;
+		btrfs_release_path(root, path);
 	}
+	ret = 0;
 	btrfs_release_path(root, path);
 
 	/* now the directory is empty */
@@ -236,10 +267,7 @@ static int btrfs_free_inode(struct btrfs_trans_handle *trans,
 			    struct btrfs_root *root,
 			    struct inode *inode)
 {
-	u64 objectid = inode->i_ino;
 	struct btrfs_path *path;
-	struct btrfs_inode_map_item *map;
-	struct btrfs_key stat_data_key;
 	int ret;
 
 	clear_inode(inode);
@@ -247,25 +275,11 @@ static int btrfs_free_inode(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 	btrfs_init_path(path);
-	ret = btrfs_lookup_inode_map(trans, root, path, objectid, -1);
-	if (ret) {
-		if (ret > 0)
-			ret = -ENOENT;
-		goto error;
-	}
-	map = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
-			    struct btrfs_inode_map_item);
-	btrfs_disk_key_to_cpu(&stat_data_key, &map->key);
-	ret = btrfs_del_item(trans, root->fs_info->inode_root, path);
-	BUG_ON(ret);
-	btrfs_release_path(root, path);
-
-	ret = btrfs_lookup_inode(trans, root, path, objectid, -1);
+	ret = btrfs_lookup_inode(trans, root, path,
+				 &BTRFS_I(inode)->location, -1);
 	BUG_ON(ret);
 	ret = btrfs_del_item(trans, root, path);
 	BUG_ON(ret);
-error:
-	btrfs_release_path(root, path);
 	btrfs_free_path(path);
 	return ret;
 }
@@ -290,6 +304,10 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
 	key.objectid = inode->i_ino;
 	key.offset = (u64)-1;
 	key.flags = 0;
+	/*
+	 * use BTRFS_CSUM_ITEM_KEY because it is larger than inline keys
+	 * or extent data
+	 */
 	btrfs_set_key_type(&key, BTRFS_CSUM_ITEM_KEY);
 	while(1) {
 		btrfs_init_path(path);
@@ -306,22 +324,27 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
 		if (btrfs_disk_key_objectid(found_key) != inode->i_ino)
 			break;
 		if (btrfs_disk_key_type(found_key) != BTRFS_CSUM_ITEM_KEY &&
+		    btrfs_disk_key_type(found_key) != BTRFS_INLINE_DATA_KEY &&
 		    btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY)
 			break;
 		if (btrfs_disk_key_offset(found_key) < inode->i_size)
 			break;
+		found_extent = 0;
 		if (btrfs_disk_key_type(found_key) == BTRFS_EXTENT_DATA_KEY) {
 			fi = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
 					    path->slots[0],
 					    struct btrfs_file_extent_item);
-			extent_start = btrfs_file_extent_disk_blocknr(fi);
-			extent_num_blocks =
-				btrfs_file_extent_disk_num_blocks(fi);
-			inode->i_blocks -=
-				btrfs_file_extent_num_blocks(fi) >> 9;
-			found_extent = 1;
-		} else {
-			found_extent = 0;
+			if (btrfs_file_extent_type(fi) !=
+			    BTRFS_FILE_EXTENT_INLINE) {
+				extent_start =
+					btrfs_file_extent_disk_blocknr(fi);
+				extent_num_blocks =
+					btrfs_file_extent_disk_num_blocks(fi);
+				/* FIXME blocksize != 4096 */
+				inode->i_blocks -=
+					btrfs_file_extent_num_blocks(fi) << 3;
+				found_extent = 1;
+			}
 		}
 		ret = btrfs_del_item(trans, root, path);
 		BUG_ON(ret);
@@ -342,7 +365,7 @@ error:
 static void btrfs_delete_inode(struct inode *inode)
 {
 	struct btrfs_trans_handle *trans;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	int ret;
 
 	truncate_inode_pages(&inode->i_data, 0);
@@ -365,65 +388,140 @@ no_delete:
 }
 
 static int btrfs_inode_by_name(struct inode *dir, struct dentry *dentry,
-			      ino_t *ino)
+			       struct btrfs_key *location)
 {
 	const char *name = dentry->d_name.name;
 	int namelen = dentry->d_name.len;
 	struct btrfs_dir_item *di;
 	struct btrfs_path *path;
-	struct btrfs_root *root = btrfs_sb(dir->i_sb);
+	struct btrfs_root *root = BTRFS_I(dir)->root;
 	int ret;
 
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 	btrfs_init_path(path);
-	ret = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
+	di = btrfs_lookup_dir_item(NULL, root, path, dir->i_ino, name,
 				    namelen, 0);
-	if (ret || !btrfs_match_dir_item_name(root, path, name, namelen)) {
-		*ino = 0;
+	if (!di || IS_ERR(di)) {
+		location->objectid = 0;
 		ret = 0;
 		goto out;
 	}
-	di = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]), path->slots[0],
-			    struct btrfs_dir_item);
-	*ino = btrfs_dir_objectid(di);
+	btrfs_disk_key_to_cpu(location, &di->location);
 out:
 	btrfs_release_path(root, path);
 	btrfs_free_path(path);
-	check_inode(dir);
 	return ret;
 }
 
+int fixup_tree_root_location(struct btrfs_root *root,
+			     struct btrfs_key *location,
+			     struct btrfs_root **sub_root)
+{
+	struct btrfs_path *path;
+	struct btrfs_root_item *ri;
+
+	if (btrfs_key_type(location) != BTRFS_ROOT_ITEM_KEY)
+		return 0;
+	if (location->objectid == BTRFS_ROOT_TREE_OBJECTID)
+		return 0;
+
+	path = btrfs_alloc_path();
+	BUG_ON(!path);
+	mutex_lock(&root->fs_info->fs_mutex);
+
+	*sub_root = btrfs_read_fs_root(root->fs_info, location);
+	if (IS_ERR(*sub_root))
+		return PTR_ERR(*sub_root);
+
+	ri = &(*sub_root)->root_item;
+	location->objectid = btrfs_root_dirid(ri);
+	location->flags = 0;
+	btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
+	location->offset = 0;
+
+	btrfs_free_path(path);
+	mutex_unlock(&root->fs_info->fs_mutex);
+	return 0;
+}
+
+int btrfs_init_locked_inode(struct inode *inode, void *p)
+{
+	struct btrfs_iget_args *args = p;
+	inode->i_ino = args->ino;
+	BTRFS_I(inode)->root = args->root;
+	return 0;
+}
+
+int btrfs_find_actor(struct inode *inode, void *opaque)
+{
+	struct btrfs_iget_args *args = opaque;
+	return (args->ino == inode->i_ino &&
+		args->root == BTRFS_I(inode)->root);
+}
+
+struct inode *btrfs_iget_locked(struct super_block *s, u64 objectid,
+				struct btrfs_root *root)
+{
+	struct inode *inode;
+	struct btrfs_iget_args args;
+	args.ino = objectid;
+	args.root = root;
+
+	inode = iget5_locked(s, objectid, btrfs_find_actor,
+			     btrfs_init_locked_inode,
+			     (void *)&args);
+	return inode;
+}
+
 static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
 				   struct nameidata *nd)
 {
 	struct inode * inode;
-	struct btrfs_root *root = btrfs_sb(dir->i_sb);
-	ino_t ino;
+	struct btrfs_inode *bi = BTRFS_I(dir);
+	struct btrfs_root *root = bi->root;
+	struct btrfs_root *sub_root = root;
+	struct btrfs_key location;
 	int 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);
+	ret = btrfs_inode_by_name(dir, dentry, &location);
 	mutex_unlock(&root->fs_info->fs_mutex);
 	if (ret < 0)
 		return ERR_PTR(ret);
 	inode = NULL;
-	if (ino) {
-		inode = iget(dir->i_sb, ino);
+	if (location.objectid) {
+		ret = fixup_tree_root_location(root, &location, &sub_root);
+		if (ret < 0)
+			return ERR_PTR(ret);
+		if (ret > 0)
+			return ERR_PTR(-ENOENT);
+		inode = btrfs_iget_locked(dir->i_sb, location.objectid,
+					  sub_root);
 		if (!inode)
 			return ERR_PTR(-EACCES);
-		check_inode(inode);
+		if (inode->i_state & I_NEW) {
+			if (sub_root != root) {
+printk("adding new root for inode %lu root %p (found %p)\n", inode->i_ino, sub_root, BTRFS_I(inode)->root);
+				igrab(inode);
+				sub_root->inode = inode;
+			}
+			BTRFS_I(inode)->root = sub_root;
+			memcpy(&BTRFS_I(inode)->location, &location,
+			       sizeof(location));
+			btrfs_read_locked_inode(inode);
+			unlock_new_inode(inode);
+		}
 	}
-	check_inode(dir);
 	return d_splice_alias(inode, dentry);
 }
 
 static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 {
 	struct inode *inode = filp->f_path.dentry->d_inode;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_item *item;
 	struct btrfs_dir_item *di;
 	struct btrfs_key key;
@@ -435,18 +533,24 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 	int advance;
 	unsigned char d_type = DT_UNKNOWN;
 	int over = 0;
-
+	u32 di_cur;
+	u32 di_total;
+	u32 di_len;
+	int key_type = BTRFS_DIR_INDEX_KEY;
+
+	/* FIXME, use a real flag for deciding about the key type */
+	if (root->fs_info->tree_root == root)
+		key_type = BTRFS_DIR_ITEM_KEY;
 	mutex_lock(&root->fs_info->fs_mutex);
 	key.objectid = inode->i_ino;
 	key.flags = 0;
-	btrfs_set_key_type(&key, BTRFS_DIR_ITEM_KEY);
+	btrfs_set_key_type(&key, key_type);
 	key.offset = filp->f_pos;
 	path = btrfs_alloc_path();
 	btrfs_init_path(path);
 	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-	if (ret < 0) {
+	if (ret < 0)
 		goto err;
-	}
 	advance = 0;
 	while(1) {
 		leaf = btrfs_buffer_leaf(path->nodes[0]);
@@ -469,23 +573,30 @@ static int btrfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 		item = leaf->items + slot;
 		if (btrfs_disk_key_objectid(&item->key) != key.objectid)
 			break;
-		if (btrfs_disk_key_type(&item->key) != BTRFS_DIR_ITEM_KEY)
-			continue;
+		if (btrfs_disk_key_type(&item->key) != key_type)
+			break;
 		if (btrfs_disk_key_offset(&item->key) < filp->f_pos)
 			continue;
-
+		filp->f_pos = btrfs_disk_key_offset(&item->key);
 		advance = 1;
 		di = btrfs_item_ptr(leaf, slot, struct btrfs_dir_item);
-		over = filldir(dirent, (const char *)(di + 1),
-			       btrfs_dir_name_len(di),
-			       btrfs_disk_key_offset(&item->key),
-			       btrfs_dir_objectid(di), d_type);
-		if (over) {
-			filp->f_pos = btrfs_disk_key_offset(&item->key);
-			break;
+		di_cur = 0;
+		di_total = btrfs_item_size(leaf->items + slot);
+		while(di_cur < di_total) {
+			over = filldir(dirent, (const char *)(di + 1),
+				       btrfs_dir_name_len(di),
+				       btrfs_disk_key_offset(&item->key),
+				       btrfs_disk_key_objectid(&di->location),
+				       d_type);
+			if (over)
+				goto nopos;
+			di_len = btrfs_dir_name_len(di) + sizeof(*di);
+			di_cur += di_len;
+			di = (struct btrfs_dir_item *)((char *)di + di_len);
 		}
-		filp->f_pos = btrfs_disk_key_offset(&item->key) + 1;
 	}
+	filp->f_pos++;
+nopos:
 	ret = 0;
 err:
 	btrfs_release_path(root, path);
@@ -511,26 +622,35 @@ static int btrfs_fill_super(struct super_block * sb, void * data, int silent)
 	struct inode * inode;
 	struct dentry * root_dentry;
 	struct btrfs_super_block *disk_super;
-	struct btrfs_root *root;
+	struct btrfs_root *tree_root;
+	struct btrfs_inode *bi;
 
 	sb->s_maxbytes = MAX_LFS_FILESIZE;
 	sb->s_magic = BTRFS_SUPER_MAGIC;
 	sb->s_op = &btrfs_super_ops;
 	sb->s_time_gran = 1;
 
-	root = open_ctree(sb);
+	tree_root = open_ctree(sb);
 
-	if (!root) {
+	if (!tree_root) {
 		printk("btrfs: open_ctree failed\n");
 		return -EIO;
 	}
-	sb->s_fs_info = root;
-	disk_super = root->fs_info->disk_super;
+	sb->s_fs_info = tree_root;
+	disk_super = tree_root->fs_info->disk_super;
 	printk("read in super total blocks %Lu root %Lu\n",
 	       btrfs_super_total_blocks(disk_super),
 	       btrfs_super_root_dir(disk_super));
 
-	inode = iget_locked(sb, btrfs_super_root_dir(disk_super));
+	inode = btrfs_iget_locked(sb, btrfs_super_root_dir(disk_super),
+				  tree_root);
+	bi = BTRFS_I(inode);
+	bi->location.objectid = inode->i_ino;
+	bi->location.offset = 0;
+	bi->location.flags = 0;
+	bi->root = tree_root;
+	btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
+
 	if (!inode)
 		return -ENOMEM;
 	if (inode->i_state & I_NEW) {
@@ -564,7 +684,6 @@ static void fill_inode_item(struct btrfs_inode_item *item,
 	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,
@@ -578,8 +697,8 @@ static int btrfs_update_inode(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 	btrfs_init_path(path);
-
-	ret = btrfs_lookup_inode(trans, root, path, inode->i_ino, 1);
+	ret = btrfs_lookup_inode(trans, root, path,
+				 &BTRFS_I(inode)->location, 1);
 	if (ret) {
 		if (ret > 0)
 			ret = -ENOENT;
@@ -592,70 +711,72 @@ static int btrfs_update_inode(struct btrfs_trans_handle *trans,
 
 	fill_inode_item(inode_item, inode);
 	btrfs_mark_buffer_dirty(path->nodes[0]);
+	ret = 0;
 failed:
 	btrfs_release_path(root, path);
 	btrfs_free_path(path);
-	check_inode(inode);
-	return 0;
+	return ret;
 }
 
 static int btrfs_write_inode(struct inode *inode, int wait)
 {
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct btrfs_trans_handle *trans;
+	int ret = 0;
+
+	if (wait) {
+		mutex_lock(&root->fs_info->fs_mutex);
+		trans = btrfs_start_transaction(root, 1);
+		ret = btrfs_commit_transaction(trans, root);
+		mutex_unlock(&root->fs_info->fs_mutex);
+	}
+	return ret;
+}
+
+static void btrfs_dirty_inode(struct inode *inode)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_trans_handle *trans;
-	int ret;
 
 	mutex_lock(&root->fs_info->fs_mutex);
 	trans = btrfs_start_transaction(root, 1);
-	ret = btrfs_update_inode(trans, root, inode);
-	if (wait)
-		btrfs_commit_transaction(trans, root);
-	else
-		btrfs_end_transaction(trans, root);
+	btrfs_update_inode(trans, root, inode);
+	btrfs_end_transaction(trans, root);
 	mutex_unlock(&root->fs_info->fs_mutex);
-	check_inode(inode);
-	return ret;
 }
 
 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
-				     struct inode *dir, int mode)
+				     struct btrfs_root *root,
+				     u64 objectid, int mode)
 {
 	struct inode *inode;
 	struct btrfs_inode_item inode_item;
-	struct btrfs_root *root = btrfs_sb(dir->i_sb);
-	struct btrfs_key key;
+	struct btrfs_key *location;
 	int ret;
-	u64 objectid;
 
-	inode = new_inode(dir->i_sb);
+	inode = new_inode(root->fs_info->sb);
 	if (!inode)
 		return ERR_PTR(-ENOMEM);
 
-	check_inode(inode);
-	ret = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
-	BUG_ON(ret);
+	BTRFS_I(inode)->root = root;
 
 	inode->i_uid = current->fsuid;
 	inode->i_gid = current->fsgid;
 	inode->i_mode = mode;
 	inode->i_ino = objectid;
 	inode->i_blocks = 0;
-	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME_SEC;
+	inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
 	fill_inode_item(&inode_item, inode);
-
-	key.objectid = objectid;
-	key.flags = 0;
-	key.offset = 0;
-	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
-	ret = btrfs_insert_inode_map(trans, root, objectid, &key);
-	BUG_ON(ret);
+	location = &BTRFS_I(inode)->location;
+	location->objectid = objectid;
+	location->flags = 0;
+	location->offset = 0;
+	btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
 
 	ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
 	BUG_ON(ret);
 
 	insert_inode_hash(inode);
-	check_inode(inode);
-	check_inode(dir);
 	return inode;
 }
 
@@ -663,17 +784,22 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans,
 			    struct dentry *dentry, struct inode *inode)
 {
 	int ret;
-	ret = btrfs_insert_dir_item(trans, btrfs_sb(inode->i_sb),
+	struct btrfs_key key;
+	struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
+	key.objectid = inode->i_ino;
+	key.flags = 0;
+	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+	key.offset = 0;
+
+	ret = btrfs_insert_dir_item(trans, root,
 				    dentry->d_name.name, dentry->d_name.len,
 				    dentry->d_parent->d_inode->i_ino,
-				    inode->i_ino, 0);
+				    &key, 0);
 	if (ret == 0) {
-		dentry->d_parent->d_inode->i_size += dentry->d_name.len;
-		ret = btrfs_update_inode(trans, btrfs_sb(inode->i_sb),
+		dentry->d_parent->d_inode->i_size += dentry->d_name.len * 2;
+		ret = btrfs_update_inode(trans, root,
 					 dentry->d_parent->d_inode);
 	}
-	check_inode(inode);
-	check_inode(dentry->d_parent->d_inode);
 	return ret;
 }
 
@@ -687,7 +813,6 @@ static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
 	}
 	if (err > 0)
 		err = -EEXIST;
-	check_inode(inode);
 	return err;
 }
 
@@ -695,14 +820,22 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
 			int mode, struct nameidata *nd)
 {
 	struct btrfs_trans_handle *trans;
-	struct btrfs_root *root = btrfs_sb(dir->i_sb);
+	struct btrfs_root *root = BTRFS_I(dir)->root;
 	struct inode *inode;
 	int err;
 	int drop_inode = 0;
+	u64 objectid;
 
 	mutex_lock(&root->fs_info->fs_mutex);
 	trans = btrfs_start_transaction(root, 1);
-	inode = btrfs_new_inode(trans, dir, mode);
+
+	err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
+	if (err) {
+		err = -ENOSPC;
+		goto out_unlock;
+	}
+
+	inode = btrfs_new_inode(trans, root, objectid, mode);
 	err = PTR_ERR(inode);
 	if (IS_ERR(inode))
 		goto out_unlock;
@@ -719,8 +852,6 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
 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);
@@ -730,24 +861,30 @@ out_unlock:
 }
 
 static int btrfs_make_empty_dir(struct btrfs_trans_handle *trans,
-				struct inode *inode, struct inode *dir)
+				struct btrfs_root *root,
+				u64 objectid, u64 dirid)
 {
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
 	int ret;
 	char buf[2];
+	struct btrfs_key key;
+
 	buf[0] = '.';
 	buf[1] = '.';
 
-	ret = btrfs_insert_dir_item(trans, root, buf, 1, inode->i_ino,
-				    inode->i_ino, 1);
+	key.objectid = objectid;
+	key.offset = 0;
+	key.flags = 0;
+	btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
+
+	ret = btrfs_insert_dir_item(trans, root, buf, 1, objectid,
+				    &key, 1);
 	if (ret)
 		goto error;
-	ret = btrfs_insert_dir_item(trans, root, buf, 2, inode->i_ino,
-				    dir->i_ino, 1);
+	key.objectid = dirid;
+	ret = btrfs_insert_dir_item(trans, root, buf, 2, objectid,
+				    &key, 1);
 	if (ret)
 		goto error;
-	inode->i_size = 3;
-	ret = btrfs_update_inode(trans, root, inode);
 error:
 	return ret;
 }
@@ -756,9 +893,10 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 {
 	struct inode *inode;
 	struct btrfs_trans_handle *trans;
-	struct btrfs_root *root = btrfs_sb(dir->i_sb);
+	struct btrfs_root *root = BTRFS_I(dir)->root;
 	int err = 0;
 	int drop_on_err = 0;
+	u64 objectid;
 
 	mutex_lock(&root->fs_info->fs_mutex);
 	trans = btrfs_start_transaction(root, 1);
@@ -766,7 +904,14 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 		err = PTR_ERR(trans);
 		goto out_unlock;
 	}
-	inode = btrfs_new_inode(trans, dir, S_IFDIR | mode);
+
+	err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
+	if (err) {
+		err = -ENOSPC;
+		goto out_unlock;
+	}
+
+	inode = btrfs_new_inode(trans, root, objectid, S_IFDIR | mode);
 	if (IS_ERR(inode)) {
 		err = PTR_ERR(inode);
 		goto out_fail;
@@ -775,7 +920,12 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
 	inode->i_op = &btrfs_dir_inode_operations;
 	inode->i_fop = &btrfs_dir_file_operations;
 
-	err = btrfs_make_empty_dir(trans, inode, dir);
+	err = btrfs_make_empty_dir(trans, root, inode->i_ino, dir->i_ino);
+	if (err)
+		goto out_fail;
+
+	inode->i_size = 6;
+	err = btrfs_update_inode(trans, root, inode);
 	if (err)
 		goto out_fail;
 	err = btrfs_add_link(trans, dentry, inode);
@@ -793,6 +943,26 @@ out_unlock:
 	return err;
 }
 
+static int btrfs_sync_file(struct file *file,
+			   struct dentry *dentry, int datasync)
+{
+	struct inode *inode = dentry->d_inode;
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	int ret;
+	struct btrfs_trans_handle *trans;
+
+	mutex_lock(&root->fs_info->fs_mutex);
+	trans = btrfs_start_transaction(root, 1);
+	if (!trans) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	ret = btrfs_commit_transaction(trans, root);
+	mutex_unlock(&root->fs_info->fs_mutex);
+out:
+	return ret > 0 ? EIO : ret;
+}
+
 static int btrfs_sync_fs(struct super_block *sb, int wait)
 {
 	struct btrfs_trans_handle *trans;
@@ -816,73 +986,6 @@ printk("btrfs sync_fs\n");
 	return 0;
 }
 
-static int btrfs_get_block_inline(struct inode *inode, sector_t iblock,
-			   struct buffer_head *result, int create)
-{
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
-	struct btrfs_path *path;
-	struct btrfs_key key;
-	struct btrfs_leaf *leaf;
-	int num_bytes = result->b_size;
-	int item_size;
-	int ret;
-	u64 pos;
-	char *ptr;
-	int copy_size;
-	int err = 0;
-	char *safe_ptr;
-	char *data_ptr;
-
-	path = btrfs_alloc_path();
-	BUG_ON(!path);
-
-	WARN_ON(create);
-	if (create) {
-		return 0;
-	}
-	pos = iblock << inode->i_blkbits;
-	key.objectid = inode->i_ino;
-	key.flags = 0;
-	btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
-	ptr = kmap(result->b_page);
-	safe_ptr = ptr;
-	ptr += (pos & (PAGE_CACHE_SIZE -1));
-again:
-	key.offset = pos;
-	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
-	if (ret) {
-		if (ret < 0)
-			err = ret;
-		else
-			err = 0;
-		goto out;
-	}
-	leaf = btrfs_buffer_leaf(path->nodes[0]);
-	item_size = btrfs_item_size(leaf->items + path->slots[0]);
-	copy_size = min(num_bytes, item_size);
-	data_ptr = btrfs_item_ptr(leaf, path->slots[0], char);
-	WARN_ON(safe_ptr + PAGE_CACHE_SIZE < ptr + copy_size);
-	memcpy(ptr, data_ptr, copy_size);
-	pos += copy_size;
-	num_bytes -= copy_size;
-	WARN_ON(num_bytes < 0);
-	ptr += copy_size;
-	btrfs_release_path(root, path);
-	if (num_bytes != 0) {
-		if (pos >= i_size_read(inode))
-			memset(ptr, 0, num_bytes);
-		else
-			goto again;
-	}
-	set_buffer_uptodate(result);
-	map_bh(result, inode->i_sb, 0);
-	err = 0;
-out:
-	btrfs_free_path(path);
-	kunmap(result->b_page);
-	return err;
-}
-
 static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
 			   struct buffer_head *result, int create)
 {
@@ -892,9 +995,9 @@ static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
 	u64 extent_start = 0;
 	u64 extent_end = 0;
 	u64 objectid = inode->i_ino;
+	u32 found_type;
 	struct btrfs_path *path;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
-	struct btrfs_trans_handle *trans = NULL;
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	struct btrfs_file_extent_item *item;
 	struct btrfs_leaf *leaf;
 	struct btrfs_disk_key *found_key;
@@ -902,11 +1005,11 @@ static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
 	path = btrfs_alloc_path();
 	BUG_ON(!path);
 	btrfs_init_path(path);
-	if (create)
-		trans = btrfs_start_transaction(root, 1);
-
+	if (create) {
+		WARN_ON(1);
+	}
 
-	ret = btrfs_lookup_file_extent(trans, root, path,
+	ret = btrfs_lookup_file_extent(NULL, root, path,
 				       inode->i_ino,
 				       iblock << inode->i_blkbits, 0);
 	if (ret < 0) {
@@ -917,7 +1020,7 @@ static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
 	if (ret != 0) {
 		if (path->slots[0] == 0) {
 			btrfs_release_path(root, path);
-			goto allocate;
+			goto out;
 		}
 		path->slots[0]--;
 	}
@@ -928,54 +1031,51 @@ static int btrfs_get_block_lock(struct inode *inode, sector_t iblock,
 	blocknr = btrfs_file_extent_disk_blocknr(item);
 	blocknr += btrfs_file_extent_offset(item);
 
-	/* exact match found, use it */
-	if (ret == 0) {
-		err = 0;
-		map_bh(result, inode->i_sb, blocknr);
-		goto out;
-	}
-
 	/* are we inside the extent that was found? */
 	found_key = &leaf->items[path->slots[0]].key;
+	found_type = btrfs_disk_key_type(found_key);
 	if (btrfs_disk_key_objectid(found_key) != objectid ||
-	    btrfs_disk_key_type(found_key) != BTRFS_EXTENT_DATA_KEY) {
+	    found_type != BTRFS_EXTENT_DATA_KEY) {
 		extent_end = 0;
 		extent_start = 0;
 		btrfs_release_path(root, path);
-		goto allocate;
-	}
-
-	extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
-	extent_start = extent_start >> inode->i_blkbits;
-	extent_start += btrfs_file_extent_offset(item);
-	extent_end = extent_start + btrfs_file_extent_num_blocks(item);
-	if (iblock >= extent_start && iblock < extent_end) {
-		err = 0;
-		map_bh(result, inode->i_sb, blocknr + iblock - extent_start);
 		goto out;
 	}
-allocate:
-	/* ok, create a new extent */
-	if (!create) {
-		err = 0;
-		goto out;
-	}
-	ret = btrfs_alloc_file_extent(trans, root, objectid,
-				      iblock << inode->i_blkbits,
-				      1, extent_end, &blocknr);
-	if (ret) {
-		err = ret;
-		goto out;
+	found_type = btrfs_file_extent_type(item);
+	extent_start = btrfs_disk_key_offset(&leaf->items[path->slots[0]].key);
+	if (found_type == BTRFS_FILE_EXTENT_REG) {
+		extent_start = extent_start >> inode->i_blkbits;
+		extent_end = extent_start + btrfs_file_extent_num_blocks(item);
+		if (iblock >= extent_start && iblock < extent_end) {
+			err = 0;
+			btrfs_map_bh_to_logical(root, result, blocknr +
+						iblock - extent_start);
+			goto out;
+		}
+	} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
+		char *ptr;
+		char *map;
+		u32 size;
+		size = btrfs_file_extent_inline_len(leaf->items +
+						    path->slots[0]);
+		extent_end = (extent_start + size) >> inode->i_blkbits;
+		extent_start >>= inode->i_blkbits;
+		if (iblock < extent_start || iblock > extent_end) {
+			goto out;
+		}
+		ptr = btrfs_file_extent_inline_start(item);
+		map = kmap(result->b_page);
+		memcpy(map, ptr, size);
+		memset(map + size, 0, PAGE_CACHE_SIZE - size);
+		flush_dcache_page(result->b_page);
+		kunmap(result->b_page);
+		set_buffer_uptodate(result);
+		SetPageChecked(result->b_page);
+		btrfs_map_bh_to_logical(root, result, 0);
 	}
-	inode->i_blocks += inode->i_sb->s_blocksize >> 9;
-	set_buffer_new(result);
-	map_bh(result, inode->i_sb, blocknr);
-
 out:
 	btrfs_release_path(root, path);
 	btrfs_free_path(path);
-	if (trans)
-		btrfs_end_transaction(trans, root);
 	return err;
 }
 
@@ -983,10 +1083,9 @@ static int btrfs_get_block(struct inode *inode, sector_t iblock,
 			   struct buffer_head *result, int create)
 {
 	int err;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	mutex_lock(&root->fs_info->fs_mutex);
-	// err = btrfs_get_block_lock(inode, iblock, result, create);
-	err = btrfs_get_block_inline(inode, iblock, result, create);
+	err = btrfs_get_block_lock(inode, iblock, result, create);
 	mutex_unlock(&root->fs_info->fs_mutex);
 	return err;
 }
@@ -994,15 +1093,8 @@ static int btrfs_get_block(struct inode *inode, sector_t iblock,
 static int btrfs_prepare_write(struct file *file, struct page *page,
 			       unsigned from, unsigned to)
 {
-	WARN_ON(1);
 	return nobh_prepare_write(page, from, to, btrfs_get_block);
 }
-static int btrfs_commit_write(struct file *file, struct page *page,
-			       unsigned from, unsigned to)
-{
-	WARN_ON(1);
-	return nobh_commit_write(file, page, from, to);
-}
 
 static void btrfs_write_super(struct super_block *sb)
 {
@@ -1014,20 +1106,232 @@ static int btrfs_readpage(struct file *file, struct page *page)
 	return mpage_readpage(page, btrfs_get_block);
 }
 
-static int btrfs_readpages(struct file *file, struct address_space *mapping,
-			   struct list_head *pages, unsigned nr_pages)
+/*
+ * While block_write_full_page is writing back the dirty buffers under
+ * the page lock, whoever dirtied the buffers may decide to clean them
+ * again at any time.  We handle that by only looking at the buffer
+ * state inside lock_buffer().
+ *
+ * If block_write_full_page() is called for regular writeback
+ * (wbc->sync_mode == WB_SYNC_NONE) then it will redirty a page which has a
+ * locked buffer.   This only can happen if someone has written the buffer
+ * directly, with submit_bh().  At the address_space level PageWriteback
+ * prevents this contention from occurring.
+ */
+static int __btrfs_write_full_page(struct inode *inode, struct page *page,
+				   struct writeback_control *wbc)
 {
-	return mpage_readpages(mapping, pages, nr_pages, btrfs_get_block);
+	int err;
+	sector_t block;
+	sector_t last_block;
+	struct buffer_head *bh, *head;
+	const unsigned blocksize = 1 << inode->i_blkbits;
+	int nr_underway = 0;
+
+	BUG_ON(!PageLocked(page));
+
+	last_block = (i_size_read(inode) - 1) >> inode->i_blkbits;
+
+	if (!page_has_buffers(page)) {
+		create_empty_buffers(page, blocksize,
+					(1 << BH_Dirty)|(1 << BH_Uptodate));
+	}
+
+	/*
+	 * Be very careful.  We have no exclusion from __set_page_dirty_buffers
+	 * here, and the (potentially unmapped) buffers may become dirty at
+	 * any time.  If a buffer becomes dirty here after we've inspected it
+	 * then we just miss that fact, and the page stays dirty.
+	 *
+	 * Buffers outside i_size may be dirtied by __set_page_dirty_buffers;
+	 * handle that here by just cleaning them.
+	 */
+
+	block = (sector_t)page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits);
+	head = page_buffers(page);
+	bh = head;
+
+	/*
+	 * Get all the dirty buffers mapped to disk addresses and
+	 * handle any aliases from the underlying blockdev's mapping.
+	 */
+	do {
+		if (block > last_block) {
+			/*
+			 * mapped buffers outside i_size will occur, because
+			 * this page can be outside i_size when there is a
+			 * truncate in progress.
+			 */
+			/*
+			 * The buffer was zeroed by block_write_full_page()
+			 */
+			clear_buffer_dirty(bh);
+			set_buffer_uptodate(bh);
+		} else if (!buffer_mapped(bh) && buffer_dirty(bh)) {
+			WARN_ON(bh->b_size != blocksize);
+			err = btrfs_get_block(inode, block, bh, 0);
+			if (err)
+				goto recover;
+			if (buffer_new(bh)) {
+				/* blockdev mappings never come here */
+				clear_buffer_new(bh);
+				unmap_underlying_metadata(bh->b_bdev,
+							bh->b_blocknr);
+			}
+		}
+		bh = bh->b_this_page;
+		block++;
+	} while (bh != head);
+
+	do {
+		if (!buffer_mapped(bh))
+			continue;
+		/*
+		 * If it's a fully non-blocking write attempt and we cannot
+		 * lock the buffer then redirty the page.  Note that this can
+		 * potentially cause a busy-wait loop from pdflush and kswapd
+		 * activity, but those code paths have their own higher-level
+		 * throttling.
+		 */
+		if (wbc->sync_mode != WB_SYNC_NONE || !wbc->nonblocking) {
+			lock_buffer(bh);
+		} else if (test_set_buffer_locked(bh)) {
+			redirty_page_for_writepage(wbc, page);
+			continue;
+		}
+		if (test_clear_buffer_dirty(bh) && bh->b_blocknr != 0) {
+			mark_buffer_async_write(bh);
+		} else {
+			unlock_buffer(bh);
+		}
+	} while ((bh = bh->b_this_page) != head);
+
+	/*
+	 * The page and its buffers are protected by PageWriteback(), so we can
+	 * drop the bh refcounts early.
+	 */
+	BUG_ON(PageWriteback(page));
+	set_page_writeback(page);
+
+	do {
+		struct buffer_head *next = bh->b_this_page;
+		if (buffer_async_write(bh)) {
+			submit_bh(WRITE, bh);
+			nr_underway++;
+		}
+		bh = next;
+	} while (bh != head);
+	unlock_page(page);
+
+	err = 0;
+done:
+	if (nr_underway == 0) {
+		/*
+		 * The page was marked dirty, but the buffers were
+		 * clean.  Someone wrote them back by hand with
+		 * ll_rw_block/submit_bh.  A rare case.
+		 */
+		int uptodate = 1;
+		do {
+			if (!buffer_uptodate(bh)) {
+				uptodate = 0;
+				break;
+			}
+			bh = bh->b_this_page;
+		} while (bh != head);
+		if (uptodate)
+			SetPageUptodate(page);
+		end_page_writeback(page);
+		/*
+		 * The page and buffer_heads can be released at any time from
+		 * here on.
+		 */
+		wbc->pages_skipped++;	/* We didn't write this page */
+	}
+	return err;
+
+recover:
+	/*
+	 * ENOSPC, or some other error.  We may already have added some
+	 * blocks to the file, so we need to write these out to avoid
+	 * exposing stale data.
+	 * The page is currently locked and not marked for writeback
+	 */
+	bh = head;
+	/* Recovery: lock and submit the mapped buffers */
+	do {
+		if (buffer_mapped(bh) && buffer_dirty(bh)) {
+			lock_buffer(bh);
+			mark_buffer_async_write(bh);
+		} else {
+			/*
+			 * The buffer may have been set dirty during
+			 * attachment to a dirty page.
+			 */
+			clear_buffer_dirty(bh);
+		}
+	} while ((bh = bh->b_this_page) != head);
+	SetPageError(page);
+	BUG_ON(PageWriteback(page));
+	set_page_writeback(page);
+	do {
+		struct buffer_head *next = bh->b_this_page;
+		if (buffer_async_write(bh)) {
+			clear_buffer_dirty(bh);
+			submit_bh(WRITE, bh);
+			nr_underway++;
+		}
+		bh = next;
+	} while (bh != head);
+	unlock_page(page);
+	goto done;
 }
 
+/*
+ * The generic ->writepage function for buffer-backed address_spaces
+ */
 static int btrfs_writepage(struct page *page, struct writeback_control *wbc)
 {
-	return nobh_writepage(page, btrfs_get_block, wbc);
+	struct inode * const inode = page->mapping->host;
+	loff_t i_size = i_size_read(inode);
+	const pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
+	unsigned offset;
+	void *kaddr;
+
+	/* Is the page fully inside i_size? */
+	if (page->index < end_index)
+		return __btrfs_write_full_page(inode, page, wbc);
+
+	/* Is the page fully outside i_size? (truncate in progress) */
+	offset = i_size & (PAGE_CACHE_SIZE-1);
+	if (page->index >= end_index+1 || !offset) {
+		/*
+		 * The page may have dirty, unmapped buffers.  For example,
+		 * they may have been added in ext3_writepage().  Make them
+		 * freeable here, so the page does not leak.
+		 */
+		block_invalidatepage(page, 0);
+		unlock_page(page);
+		return 0; /* don't care */
+	}
+
+	/*
+	 * The page straddles i_size.  It must be zeroed out on each and every
+	 * writepage invokation because it may be mmapped.  "A file is mapped
+	 * in multiples of the page size.  For a file that is not a multiple of
+	 * the  page size, the remaining memory is zeroed when mapped, and
+	 * writes to that region are not written out to the file."
+	 */
+	kaddr = kmap_atomic(page, KM_USER0);
+	memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
+	flush_dcache_page(page);
+	kunmap_atomic(kaddr, KM_USER0);
+	return __btrfs_write_full_page(inode, page, wbc);
 }
 
 static void btrfs_truncate(struct inode *inode)
 {
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
+	struct btrfs_root *root = BTRFS_I(inode)->root;
 	int ret;
 	struct btrfs_trans_handle *trans;
 
@@ -1049,6 +1353,29 @@ static void btrfs_truncate(struct inode *inode)
 	mark_inode_dirty(inode);
 }
 
+/*
+ * Make sure any changes to nobh_commit_write() are reflected in
+ * nobh_truncate_page(), since it doesn't call commit_write().
+ */
+static int btrfs_commit_write(struct file *file, struct page *page,
+			      unsigned from, unsigned to)
+{
+	struct inode *inode = page->mapping->host;
+	struct buffer_head *bh;
+	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+
+	SetPageUptodate(page);
+	bh = page_buffers(page);
+	if (buffer_mapped(bh) && bh->b_blocknr != 0) {
+		set_page_dirty(page);
+	}
+	if (pos > inode->i_size) {
+		i_size_write(inode, pos);
+		mark_inode_dirty(inode);
+	}
+	return 0;
+}
+
 static int btrfs_copy_from_user(loff_t pos, int num_pages, int write_bytes,
 				struct page **prepared_pages,
 				const char __user * buf)
@@ -1104,6 +1431,8 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
 	int ret;
 	int this_write;
 	struct inode *inode = file->f_path.dentry->d_inode;
+	struct buffer_head *bh;
+	struct btrfs_file_extent_item *ei;
 
 	for (i = 0; i < num_pages; i++) {
 		offset = pos & (PAGE_CACHE_SIZE -1);
@@ -1112,16 +1441,47 @@ static int dirty_and_release_pages(struct btrfs_trans_handle *trans,
 
 		mutex_lock(&root->fs_info->fs_mutex);
 		trans = btrfs_start_transaction(root, 1);
-		btrfs_csum_file_block(trans, root, inode->i_ino,
+
+		bh = page_buffers(pages[i]);
+		if (buffer_mapped(bh) && bh->b_blocknr == 0) {
+			struct btrfs_key key;
+			struct btrfs_path *path;
+			char *ptr;
+			u32 datasize;
+
+			path = btrfs_alloc_path();
+			BUG_ON(!path);
+			key.objectid = inode->i_ino;
+			key.offset = pages[i]->index << PAGE_CACHE_SHIFT;
+			key.flags = 0;
+			btrfs_set_key_type(&key, BTRFS_EXTENT_DATA_KEY);
+			BUG_ON(write_bytes >= PAGE_CACHE_SIZE);
+			datasize = offset +
+				btrfs_file_extent_calc_inline_size(write_bytes);
+			ret = btrfs_insert_empty_item(trans, root, path, &key,
+						      datasize);
+			BUG_ON(ret);
+			ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+			       path->slots[0], struct btrfs_file_extent_item);
+			btrfs_set_file_extent_generation(ei, trans->transid);
+			btrfs_set_file_extent_type(ei,
+						   BTRFS_FILE_EXTENT_INLINE);
+			ptr = btrfs_file_extent_inline_start(ei);
+			memcpy(ptr, bh->b_data, offset + write_bytes);
+			mark_buffer_dirty(path->nodes[0]);
+			btrfs_free_path(path);
+		} else {
+			btrfs_csum_file_block(trans, root, inode->i_ino,
 				      pages[i]->index << PAGE_CACHE_SHIFT,
 				      kmap(pages[i]), PAGE_CACHE_SIZE);
-		kunmap(pages[i]);
+			kunmap(pages[i]);
+		}
 		SetPageChecked(pages[i]);
 		ret = btrfs_end_transaction(trans, root);
 		BUG_ON(ret);
 		mutex_unlock(&root->fs_info->fs_mutex);
 
-		ret = nobh_commit_write(file, pages[i], offset,
+		ret = btrfs_commit_write(file, pages[i], offset,
 					 offset + this_write);
 		pos += this_write;
 		if (ret) {
@@ -1135,21 +1495,214 @@ failed:
 	return err;
 }
 
-static int prepare_pages(struct btrfs_trans_handle *trans,
-			 struct btrfs_root *root,
+static int drop_extents(struct btrfs_trans_handle *trans,
+			  struct btrfs_root *root,
+			  struct inode *inode,
+			  u64 start, u64 end)
+{
+	int ret;
+	struct btrfs_key key;
+	struct btrfs_leaf *leaf;
+	int slot;
+	struct btrfs_file_extent_item *extent;
+	u64 extent_end = 0;
+	int keep;
+	struct btrfs_file_extent_item old;
+	struct btrfs_path *path;
+	u64 search_start = start;
+	int bookend;
+	int found_type;
+	int found_extent;
+	int found_inline;
+
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+	while(1) {
+		btrfs_release_path(root, path);
+		ret = btrfs_lookup_file_extent(trans, root, path, inode->i_ino,
+					       search_start, -1);
+		if (ret < 0)
+			goto out;
+		if (ret > 0) {
+			if (path->slots[0] == 0) {
+				ret = 0;
+				goto out;
+			}
+			path->slots[0]--;
+		}
+		keep = 0;
+		bookend = 0;
+		found_extent = 0;
+		found_inline = 0;
+		extent = NULL;
+		leaf = btrfs_buffer_leaf(path->nodes[0]);
+		slot = path->slots[0];
+		btrfs_disk_key_to_cpu(&key, &leaf->items[slot].key);
+		if (key.offset >= end || key.objectid != inode->i_ino) {
+			ret = 0;
+			goto out;
+		}
+		if (btrfs_key_type(&key) != BTRFS_EXTENT_DATA_KEY) {
+			ret = 0;
+			goto out;
+		}
+		extent = btrfs_item_ptr(leaf, slot,
+					struct btrfs_file_extent_item);
+		found_type = btrfs_file_extent_type(extent);
+		if (found_type == BTRFS_FILE_EXTENT_REG) {
+			extent_end = key.offset +
+				(btrfs_file_extent_num_blocks(extent) <<
+				 inode->i_blkbits);
+			found_extent = 1;
+		} else if (found_type == BTRFS_FILE_EXTENT_INLINE) {
+			found_inline = 1;
+			extent_end = key.offset +
+			     btrfs_file_extent_inline_len(leaf->items + slot);
+		}
+
+		if (!found_extent && !found_inline) {
+			ret = 0;
+			goto out;
+		}
+
+		if (search_start >= extent_end) {
+			ret = 0;
+			goto out;
+		}
+
+		search_start = extent_end;
+
+		if (end < extent_end && end >= key.offset) {
+			if (found_extent) {
+				memcpy(&old, extent, sizeof(old));
+				ret = btrfs_inc_extent_ref(trans, root,
+				      btrfs_file_extent_disk_blocknr(&old),
+				      btrfs_file_extent_disk_num_blocks(&old));
+				BUG_ON(ret);
+			}
+			WARN_ON(found_inline);
+			bookend = 1;
+		}
+
+		if (start > key.offset) {
+			u64 new_num;
+			u64 old_num;
+			/* truncate existing extent */
+			keep = 1;
+			WARN_ON(start & (root->blocksize - 1));
+			if (found_extent) {
+				new_num = (start - key.offset) >>
+					inode->i_blkbits;
+				old_num = btrfs_file_extent_num_blocks(extent);
+				inode->i_blocks -= (old_num - new_num) << 3;
+				btrfs_set_file_extent_num_blocks(extent,
+								 new_num);
+				mark_buffer_dirty(path->nodes[0]);
+			} else {
+				WARN_ON(1);
+				/*
+				ret = btrfs_truncate_item(trans, root, path,
+							  start - key.offset);
+				BUG_ON(ret);
+				*/
+			}
+		}
+		if (!keep) {
+			u64 disk_blocknr = 0;
+			u64 disk_num_blocks = 0;
+			u64 extent_num_blocks = 0;
+			if (found_extent) {
+				disk_blocknr =
+				      btrfs_file_extent_disk_blocknr(extent);
+				disk_num_blocks =
+				      btrfs_file_extent_disk_num_blocks(extent);
+				extent_num_blocks =
+				      btrfs_file_extent_num_blocks(extent);
+			}
+			ret = btrfs_del_item(trans, root, path);
+			BUG_ON(ret);
+			btrfs_release_path(root, path);
+			if (found_extent) {
+				inode->i_blocks -=
+				btrfs_file_extent_num_blocks(extent) << 3;
+				ret = btrfs_free_extent(trans, root,
+							disk_blocknr,
+							disk_num_blocks, 0);
+			}
+
+			BUG_ON(ret);
+			if (!bookend && search_start >= end) {
+				ret = 0;
+				goto out;
+			}
+			if (!bookend)
+				continue;
+		}
+		if (bookend && found_extent) {
+			/* create bookend */
+			struct btrfs_key ins;
+			ins.objectid = inode->i_ino;
+			ins.offset = end;
+			ins.flags = 0;
+			btrfs_set_key_type(&ins, BTRFS_EXTENT_DATA_KEY);
+
+			btrfs_release_path(root, path);
+			ret = btrfs_insert_empty_item(trans, root, path, &ins,
+						      sizeof(*extent));
+			BUG_ON(ret);
+			extent = btrfs_item_ptr(
+				    btrfs_buffer_leaf(path->nodes[0]),
+				    path->slots[0],
+				    struct btrfs_file_extent_item);
+			btrfs_set_file_extent_disk_blocknr(extent,
+				    btrfs_file_extent_disk_blocknr(&old));
+			btrfs_set_file_extent_disk_num_blocks(extent,
+				    btrfs_file_extent_disk_num_blocks(&old));
+
+			btrfs_set_file_extent_offset(extent,
+				    btrfs_file_extent_offset(&old) +
+				    ((end - key.offset) >> inode->i_blkbits));
+			WARN_ON(btrfs_file_extent_num_blocks(&old) <
+				(end - key.offset) >> inode->i_blkbits);
+			btrfs_set_file_extent_num_blocks(extent,
+				    btrfs_file_extent_num_blocks(&old) -
+				    ((end - key.offset) >> inode->i_blkbits));
+
+			btrfs_set_file_extent_type(extent,
+						   BTRFS_FILE_EXTENT_REG);
+			btrfs_set_file_extent_generation(extent,
+				    btrfs_file_extent_generation(&old));
+			btrfs_mark_buffer_dirty(path->nodes[0]);
+			inode->i_blocks +=
+				btrfs_file_extent_num_blocks(extent) << 3;
+			ret = 0;
+			goto out;
+		}
+	}
+out:
+	btrfs_free_path(path);
+	return ret;
+}
+
+static int prepare_pages(struct btrfs_root *root,
 			 struct file *file,
 			 struct page **pages,
 			 size_t num_pages,
 			 loff_t pos,
-			 size_t write_bytes)
+			 unsigned long first_index,
+			 unsigned long last_index,
+			 size_t write_bytes,
+			 u64 alloc_extent_start)
 {
 	int i;
 	unsigned long index = pos >> PAGE_CACHE_SHIFT;
 	struct inode *inode = file->f_path.dentry->d_inode;
 	int offset;
 	int err = 0;
-	int ret;
 	int this_write;
+	struct buffer_head *bh;
+	struct buffer_head *head;
 	loff_t isize = i_size_read(inode);
 
 	memset(pages, 0, num_pages * sizeof(struct page *));
@@ -1162,14 +1715,21 @@ static int prepare_pages(struct btrfs_trans_handle *trans,
 		}
 		offset = pos & (PAGE_CACHE_SIZE -1);
 		this_write = min(PAGE_CACHE_SIZE - offset, write_bytes);
-		ret = nobh_prepare_write(pages[i], offset,
-					 offset + this_write,
-					 btrfs_get_block);
+		create_empty_buffers(pages[i], root->fs_info->sb->s_blocksize,
+				     (1 << BH_Uptodate));
+		head = page_buffers(pages[i]);
+		bh = head;
+		do {
+			err = btrfs_map_bh_to_logical(root, bh,
+						      alloc_extent_start);
+			BUG_ON(err);
+			if (err)
+				goto failed_truncate;
+			bh = bh->b_this_page;
+			if (alloc_extent_start)
+				alloc_extent_start++;
+		} while (bh != head);
 		pos += this_write;
-		if (ret) {
-			err = ret;
-			goto failed_truncate;
-		}
 		WARN_ON(this_write > write_bytes);
 		write_bytes -= this_write;
 	}
@@ -1194,13 +1754,20 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
 	int err = 0;
 	int ret = 0;
 	struct inode *inode = file->f_path.dentry->d_inode;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
-	struct page *pages[1];
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct page *pages[8];
+	struct page *pinned[2] = { NULL, NULL };
+	unsigned long first_index;
+	unsigned long last_index;
+	u64 start_pos;
+	u64 num_blocks;
+	u64 alloc_extent_start;
+	struct btrfs_trans_handle *trans;
+	struct btrfs_key ins;
 
 	if (file->f_flags & O_DIRECT)
 		return -EINVAL;
 	pos = *ppos;
-
 	vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
 	current->backing_dev_info = inode->i_mapping->backing_dev_info;
 	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
@@ -1212,187 +1779,96 @@ static ssize_t btrfs_file_write(struct file *file, const char __user *buf,
 	if (err)
 		goto out;
 	file_update_time(file);
-	mutex_lock(&inode->i_mutex);
-	while(count > 0) {
-		size_t offset = pos & (PAGE_CACHE_SIZE - 1);
-		size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
-		size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
-					PAGE_CACHE_SHIFT;
-		ret = prepare_pages(NULL, root, file, pages, num_pages,
-				    pos, write_bytes);
-		BUG_ON(ret);
-		ret = btrfs_copy_from_user(pos, num_pages,
-					   write_bytes, pages, buf);
-		BUG_ON(ret);
 
-		ret = dirty_and_release_pages(NULL, root, file, pages,
-					      num_pages, pos, write_bytes);
-		BUG_ON(ret);
-		btrfs_drop_pages(pages, num_pages);
+	start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1);
+	num_blocks = (count + pos - start_pos + root->blocksize - 1) >>
+			inode->i_blkbits;
 
-		buf += write_bytes;
-		count -= write_bytes;
-		pos += write_bytes;
-		num_written += write_bytes;
-
-		balance_dirty_pages_ratelimited(inode->i_mapping);
-		cond_resched();
+	mutex_lock(&inode->i_mutex);
+	first_index = pos >> PAGE_CACHE_SHIFT;
+	last_index = (pos + count) >> PAGE_CACHE_SHIFT;
+
+	if ((first_index << PAGE_CACHE_SHIFT) < inode->i_size &&
+	    (pos & (PAGE_CACHE_SIZE - 1))) {
+		pinned[0] = grab_cache_page(inode->i_mapping, first_index);
+		if (!PageUptodate(pinned[0])) {
+			ret = mpage_readpage(pinned[0], btrfs_get_block);
+			BUG_ON(ret);
+		} else {
+			unlock_page(pinned[0]);
+		}
+	}
+	if (first_index != last_index &&
+	    (last_index << PAGE_CACHE_SHIFT) < inode->i_size &&
+	    (count & (PAGE_CACHE_SIZE - 1))) {
+		pinned[1] = grab_cache_page(inode->i_mapping, last_index);
+		if (!PageUptodate(pinned[1])) {
+			ret = mpage_readpage(pinned[1], btrfs_get_block);
+			BUG_ON(ret);
+		} else {
+			unlock_page(pinned[1]);
+		}
 	}
-	mutex_unlock(&inode->i_mutex);
-out:
-	*ppos = pos;
-	current->backing_dev_info = NULL;
-	return num_written ? num_written : err;
-}
-
-static ssize_t inline_one_page(struct btrfs_root *root, struct inode *inode,
-			   struct page *page, loff_t pos,
-			   size_t offset, size_t write_bytes)
-{
-	struct btrfs_path *path;
-	struct btrfs_trans_handle *trans;
-	struct btrfs_key key;
-	struct btrfs_leaf *leaf;
-	struct btrfs_key found_key;
-	int ret;
-	size_t copy_size = 0;
-	char *dst = NULL;
-	int err = 0;
-	size_t num_written = 0;
 
-	path = btrfs_alloc_path();
-	BUG_ON(!path);
 	mutex_lock(&root->fs_info->fs_mutex);
 	trans = btrfs_start_transaction(root, 1);
-	key.objectid = inode->i_ino;
-	key.flags = 0;
-	btrfs_set_key_type(&key, BTRFS_INLINE_DATA_KEY);
-
-again:
-	key.offset = pos;
-	ret = btrfs_search_slot(trans, root, &key, path, 0, 1);
-	if (ret < 0) {
-		err = ret;
-		goto out;
+	if (!trans) {
+		err = -ENOMEM;
+		mutex_unlock(&root->fs_info->fs_mutex);
+		goto out_unlock;
 	}
-	if (ret == 0) {
-		leaf = btrfs_buffer_leaf(path->nodes[0]);
-		btrfs_disk_key_to_cpu(&found_key,
-				      &leaf->items[path->slots[0]].key);
-		copy_size = btrfs_item_size(leaf->items + path->slots[0]);
-		dst = btrfs_item_ptr(leaf, path->slots[0], char);
-		copy_size = min(write_bytes, copy_size);
-		goto copyit;
+	/* FIXME blocksize != 4096 */
+	inode->i_blocks += num_blocks << 3;
+	if (start_pos < inode->i_size) {
+		/* FIXME blocksize != pagesize */
+		ret = drop_extents(trans, root, inode,
+				   start_pos,
+				   (pos + count + root->blocksize -1) &
+				   ~((u64)root->blocksize - 1));
+		BUG_ON(ret);
+	}
+	if (inode->i_size >= PAGE_CACHE_SIZE || pos + count < inode->i_size ||
+	    pos + count - start_pos > BTRFS_MAX_INLINE_DATA_SIZE(root)) {
+		ret = btrfs_alloc_extent(trans, root, inode->i_ino,
+					 BTRFS_EXTENT_FILE, num_blocks, 1,
+					 (u64)-1, &ins);
+		BUG_ON(ret);
+		ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
+				       start_pos, ins.objectid, ins.offset);
+		BUG_ON(ret);
 	} else {
-		int slot = path->slots[0];
-		if (slot > 0) {
-			slot--;
-		}
-		// FIXME find max key
-		leaf = btrfs_buffer_leaf(path->nodes[0]);
-		btrfs_disk_key_to_cpu(&found_key,
-				      &leaf->items[slot].key);
-		if (found_key.objectid != inode->i_ino)
-			goto insert;
-		if (btrfs_key_type(&found_key) != BTRFS_INLINE_DATA_KEY)
-			goto insert;
-		copy_size = btrfs_item_size(leaf->items + slot);
-		if (found_key.offset + copy_size <= pos)
-			goto insert;
-		dst = btrfs_item_ptr(leaf, path->slots[0], char);
-		dst += pos - found_key.offset;
-		copy_size = copy_size - (pos - found_key.offset);
-		BUG_ON(copy_size < 0);
-		copy_size = min(write_bytes, copy_size);
-		WARN_ON(copy_size == 0);
-		goto copyit;
+		ins.offset = 0;
+		ins.objectid = 0;
 	}
-insert:
-	btrfs_release_path(root, path);
-	copy_size = min(write_bytes, (size_t)512);
-	ret = btrfs_insert_empty_item(trans, root, path, &key, copy_size);
 	BUG_ON(ret);
-	dst = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
-			     path->slots[0], char);
-copyit:
-	WARN_ON(copy_size == 0);
-	WARN_ON(dst + copy_size >
-		btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
-						 path->slots[0], char) +
-		btrfs_item_size(btrfs_buffer_leaf(path->nodes[0])->items +
-						  path->slots[0]));
-	btrfs_memcpy(root, path->nodes[0]->b_data, dst,
-		     page_address(page) + offset, copy_size);
-	mark_buffer_dirty(path->nodes[0]);
-	btrfs_release_path(root, path);
-	pos += copy_size;
-	offset += copy_size;
-	num_written += copy_size;
-	write_bytes -= copy_size;
-	if (write_bytes)
-		goto again;
-out:
-	btrfs_free_path(path);
+	alloc_extent_start = ins.objectid;
 	ret = btrfs_end_transaction(trans, root);
-	BUG_ON(ret);
 	mutex_unlock(&root->fs_info->fs_mutex);
-	return num_written ? num_written : err;
-}
 
-static ssize_t btrfs_file_inline_write(struct file *file,
-				       const char __user *buf,
-				       size_t count, loff_t *ppos)
-{
-	loff_t pos;
-	size_t num_written = 0;
-	int err = 0;
-	int ret = 0;
-	struct inode *inode = file->f_path.dentry->d_inode;
-	struct btrfs_root *root = btrfs_sb(inode->i_sb);
-	unsigned long page_index;
-
-	if (file->f_flags & O_DIRECT)
-		return -EINVAL;
-	pos = *ppos;
-
-	vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
-	current->backing_dev_info = inode->i_mapping->backing_dev_info;
-	err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
-	if (err)
-		goto out;
-	if (count == 0)
-		goto out;
-	err = remove_suid(file->f_path.dentry);
-	if (err)
-		goto out;
-	file_update_time(file);
-	mutex_lock(&inode->i_mutex);
 	while(count > 0) {
 		size_t offset = pos & (PAGE_CACHE_SIZE - 1);
 		size_t write_bytes = min(count, PAGE_CACHE_SIZE - offset);
-		struct page *page;
+		size_t num_pages = (write_bytes + PAGE_CACHE_SIZE - 1) >>
+					PAGE_CACHE_SHIFT;
 
-		page_index = pos >> PAGE_CACHE_SHIFT;
-		page = grab_cache_page(inode->i_mapping, page_index);
-		if (!PageUptodate(page)) {
-			ret = mpage_readpage(page, btrfs_get_block);
-			BUG_ON(ret);
-			lock_page(page);
-		}
-		ret = btrfs_copy_from_user(pos, 1,
-					   write_bytes, &page, buf);
+		memset(pages, 0, sizeof(pages));
+		ret = prepare_pages(root, file, pages, num_pages,
+				    pos, first_index, last_index,
+				    write_bytes, alloc_extent_start);
 		BUG_ON(ret);
-		write_bytes = inline_one_page(root, inode, page, pos,
-				      offset, write_bytes);
-		SetPageUptodate(page);
-		if (write_bytes > 0 && pos + write_bytes > inode->i_size) {
-			i_size_write(inode, pos + write_bytes);
-			mark_inode_dirty(inode);
-		}
-		page_cache_release(page);
-		unlock_page(page);
-		if (write_bytes < 0)
-			goto out_unlock;
+
+		/* FIXME blocks != pagesize */
+		if (alloc_extent_start)
+			alloc_extent_start += num_pages;
+		ret = btrfs_copy_from_user(pos, num_pages,
+					   write_bytes, pages, buf);
+		BUG_ON(ret);
+
+		ret = dirty_and_release_pages(NULL, root, file, pages,
+					      num_pages, pos, write_bytes);
+		BUG_ON(ret);
+		btrfs_drop_pages(pages, num_pages);
+
 		buf += write_bytes;
 		count -= write_bytes;
 		pos += write_bytes;
@@ -1404,8 +1880,13 @@ static ssize_t btrfs_file_inline_write(struct file *file,
 out_unlock:
 	mutex_unlock(&inode->i_mutex);
 out:
+	if (pinned[0])
+		page_cache_release(pinned[0]);
+	if (pinned[1])
+		page_cache_release(pinned[1]);
 	*ppos = pos;
 	current->backing_dev_info = NULL;
+	mark_inode_dirty(inode);
 	return num_written ? num_written : err;
 }
 
@@ -1414,17 +1895,19 @@ static int btrfs_read_actor(read_descriptor_t *desc, struct page *page,
 {
 	char *kaddr;
 	unsigned long left, count = desc->count;
+	struct inode *inode = page->mapping->host;
 
 	if (size > count)
 		size = count;
 
 	if (!PageChecked(page)) {
 		/* FIXME, do it per block */
-		struct btrfs_root *root = btrfs_sb(page->mapping->host->i_sb);
+		struct btrfs_root *root = BTRFS_I(inode)->root;
+
 		int ret = btrfs_csum_verify_file_block(root,
-					  page->mapping->host->i_ino,
-					  page->index << PAGE_CACHE_SHIFT,
-					  kmap(page), PAGE_CACHE_SIZE);
+				  page->mapping->host->i_ino,
+				  page->index << PAGE_CACHE_SHIFT,
+				  kmap(page), PAGE_CACHE_SIZE);
 		if (ret) {
 			printk("failed to verify ino %lu page %lu\n",
 			       page->mapping->host->i_ino,
@@ -1521,6 +2004,291 @@ static ssize_t btrfs_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
 	return retval;
 }
 
+static int create_subvol(struct btrfs_root *root, char *name, int namelen)
+{
+	struct btrfs_trans_handle *trans;
+	struct btrfs_key key;
+	struct btrfs_root_item root_item;
+	struct btrfs_inode_item *inode_item;
+	struct buffer_head *subvol;
+	struct btrfs_leaf *leaf;
+	struct btrfs_root *new_root;
+	struct inode *inode;
+	int ret;
+	u64 objectid;
+	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
+
+	mutex_lock(&root->fs_info->fs_mutex);
+	trans = btrfs_start_transaction(root, 1);
+	BUG_ON(!trans);
+
+	subvol = btrfs_alloc_free_block(trans, root);
+	if (subvol == NULL)
+		return -ENOSPC;
+	leaf = btrfs_buffer_leaf(subvol);
+	btrfs_set_header_nritems(&leaf->header, 0);
+	btrfs_set_header_level(&leaf->header, 0);
+	btrfs_set_header_blocknr(&leaf->header, bh_blocknr(subvol));
+	btrfs_set_header_generation(&leaf->header, trans->transid);
+	btrfs_set_header_owner(&leaf->header, root->root_key.objectid);
+	memcpy(leaf->header.fsid, root->fs_info->disk_super->fsid,
+	       sizeof(leaf->header.fsid));
+	mark_buffer_dirty(subvol);
+
+	inode_item = &root_item.inode;
+	memset(inode_item, 0, sizeof(*inode_item));
+	btrfs_set_inode_generation(inode_item, 1);
+	btrfs_set_inode_size(inode_item, 3);
+	btrfs_set_inode_nlink(inode_item, 1);
+	btrfs_set_inode_nblocks(inode_item, 1);
+	btrfs_set_inode_mode(inode_item, S_IFDIR | 0755);
+
+	btrfs_set_root_blocknr(&root_item, bh_blocknr(subvol));
+	btrfs_set_root_refs(&root_item, 1);
+	brelse(subvol);
+	subvol = NULL;
+
+	ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
+				       0, &objectid);
+	BUG_ON(ret);
+
+	btrfs_set_root_dirid(&root_item, new_dirid);
+
+	key.objectid = objectid;
+	key.offset = 1;
+	key.flags = 0;
+	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
+				&root_item);
+	BUG_ON(ret);
+
+	/*
+	 * insert the directory item
+	 */
+	key.offset = (u64)-1;
+	ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
+				    name, namelen,
+				    root->fs_info->sb->s_root->d_inode->i_ino,
+				    &key, 0);
+	BUG_ON(ret);
+
+	ret = btrfs_commit_transaction(trans, root);
+	BUG_ON(ret);
+
+	new_root = btrfs_read_fs_root(root->fs_info, &key);
+	BUG_ON(!new_root);
+
+	trans = btrfs_start_transaction(new_root, 1);
+	BUG_ON(!trans);
+
+	inode = btrfs_new_inode(trans, new_root, new_dirid, S_IFDIR | 0700);
+	inode->i_op = &btrfs_dir_inode_operations;
+	inode->i_fop = &btrfs_dir_file_operations;
+
+	ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
+	BUG_ON(ret);
+
+	inode->i_nlink = 1;
+	inode->i_size = 6;
+	ret = btrfs_update_inode(trans, new_root, inode);
+	BUG_ON(ret);
+
+	ret = btrfs_commit_transaction(trans, new_root);
+	BUG_ON(ret);
+
+	iput(inode);
+
+	mutex_unlock(&root->fs_info->fs_mutex);
+	return 0;
+}
+
+static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
+{
+	struct btrfs_trans_handle *trans;
+	struct btrfs_key key;
+	struct btrfs_root_item new_root_item;
+	int ret;
+	u64 objectid;
+
+	if (!root->ref_cows)
+		return -EINVAL;
+
+	mutex_lock(&root->fs_info->fs_mutex);
+	trans = btrfs_start_transaction(root, 1);
+	BUG_ON(!trans);
+
+	ret = btrfs_update_inode(trans, root, root->inode);
+	BUG_ON(ret);
+
+	ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
+				       0, &objectid);
+	BUG_ON(ret);
+
+	memcpy(&new_root_item, &root->root_item,
+	       sizeof(new_root_item));
+
+	key.objectid = objectid;
+	key.offset = 1;
+	key.flags = 0;
+	btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+	btrfs_set_root_blocknr(&new_root_item, bh_blocknr(root->node));
+
+	ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
+				&new_root_item);
+	BUG_ON(ret);
+
+	/*
+	 * insert the directory item
+	 */
+	key.offset = (u64)-1;
+	ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
+				    name, namelen,
+				    root->fs_info->sb->s_root->d_inode->i_ino,
+				    &key, 0);
+
+	BUG_ON(ret);
+
+	ret = btrfs_inc_root_ref(trans, root);
+	BUG_ON(ret);
+
+	ret = btrfs_commit_transaction(trans, root);
+	BUG_ON(ret);
+	mutex_unlock(&root->fs_info->fs_mutex);
+	return 0;
+}
+
+static int add_disk(struct btrfs_root *root, char *name, int namelen)
+{
+	struct block_device *bdev;
+	struct btrfs_path *path;
+	struct super_block *sb = root->fs_info->sb;
+	struct btrfs_root *dev_root = root->fs_info->dev_root;
+	struct btrfs_trans_handle *trans;
+	struct btrfs_device_item *dev_item;
+	struct btrfs_key key;
+	u16 item_size;
+	u64 num_blocks;
+	u64 new_blocks;
+	u64 device_id;
+	int ret;
+
+printk("adding disk %s\n", name);
+	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
+	num_blocks = btrfs_super_total_blocks(root->fs_info->disk_super);
+	bdev = open_bdev_excl(name, O_RDWR, sb);
+	if (IS_ERR(bdev)) {
+		ret = PTR_ERR(bdev);
+printk("open bdev excl failed ret %d\n", ret);
+		goto out_nolock;
+	}
+	set_blocksize(bdev, sb->s_blocksize);
+	new_blocks = bdev->bd_inode->i_size >> sb->s_blocksize_bits;
+	key.objectid = num_blocks;
+	key.offset = new_blocks;
+	key.flags = 0;
+	btrfs_set_key_type(&key, BTRFS_DEV_ITEM_KEY);
+
+	mutex_lock(&dev_root->fs_info->fs_mutex);
+	trans = btrfs_start_transaction(dev_root, 1);
+	item_size = sizeof(*dev_item) + namelen;
+printk("insert empty on %Lu %Lu %u size %d\n", num_blocks, new_blocks, key.flags, item_size);
+	ret = btrfs_insert_empty_item(trans, dev_root, path, &key, item_size);
+	if (ret) {
+printk("insert failed %d\n", ret);
+		close_bdev_excl(bdev);
+		if (ret > 0)
+			ret = -EEXIST;
+		goto out;
+	}
+	dev_item = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
+				  path->slots[0], struct btrfs_device_item);
+	btrfs_set_device_pathlen(dev_item, namelen);
+	memcpy(dev_item + 1, name, namelen);
+
+	device_id = btrfs_super_last_device_id(root->fs_info->disk_super) + 1;
+	btrfs_set_super_last_device_id(root->fs_info->disk_super, device_id);
+	btrfs_set_device_id(dev_item, device_id);
+	mark_buffer_dirty(path->nodes[0]);
+
+	ret = btrfs_insert_dev_radix(root, bdev, device_id, num_blocks,
+				     new_blocks);
+
+	if (!ret) {
+		btrfs_set_super_total_blocks(root->fs_info->disk_super,
+					     num_blocks + new_blocks);
+		i_size_write(root->fs_info->btree_inode,
+			     (num_blocks + new_blocks) <<
+			     root->fs_info->btree_inode->i_blkbits);
+	}
+
+out:
+	ret = btrfs_commit_transaction(trans, dev_root);
+	BUG_ON(ret);
+	mutex_unlock(&root->fs_info->fs_mutex);
+out_nolock:
+	btrfs_free_path(path);
+
+	return ret;
+}
+
+static int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
+		       cmd, unsigned long arg)
+{
+	struct btrfs_root *root = BTRFS_I(inode)->root;
+	struct btrfs_ioctl_vol_args vol_args;
+	int ret = 0;
+	struct btrfs_dir_item *di;
+	int namelen;
+	struct btrfs_path *path;
+	u64 root_dirid;
+
+	switch (cmd) {
+	case BTRFS_IOC_SNAP_CREATE:
+		if (copy_from_user(&vol_args,
+				   (struct btrfs_ioctl_vol_args __user *)arg,
+				   sizeof(vol_args)))
+			return -EFAULT;
+		namelen = strlen(vol_args.name);
+		if (namelen > BTRFS_VOL_NAME_MAX)
+			return -EINVAL;
+		path = btrfs_alloc_path();
+		if (!path)
+			return -ENOMEM;
+		root_dirid = root->fs_info->sb->s_root->d_inode->i_ino,
+		mutex_lock(&root->fs_info->fs_mutex);
+		di = btrfs_lookup_dir_item(NULL, root->fs_info->tree_root,
+				    path, root_dirid,
+				    vol_args.name, namelen, 0);
+		mutex_unlock(&root->fs_info->fs_mutex);
+		btrfs_free_path(path);
+		if (di && !IS_ERR(di))
+			return -EEXIST;
+
+		if (root == root->fs_info->tree_root)
+			ret = create_subvol(root, vol_args.name, namelen);
+		else
+			ret = create_snapshot(root, vol_args.name, namelen);
+		WARN_ON(ret);
+		break;
+	case BTRFS_IOC_ADD_DISK:
+		if (copy_from_user(&vol_args,
+				   (struct btrfs_ioctl_vol_args __user *)arg,
+				   sizeof(vol_args)))
+			return -EFAULT;
+		namelen = strlen(vol_args.name);
+		if (namelen > BTRFS_VOL_NAME_MAX)
+			return -EINVAL;
+		vol_args.name[namelen] = '\0';
+		ret = add_disk(root, vol_args.name, namelen);
+		break;
+	default:
+		return -ENOTTY;
+	}
+	return ret;
+}
+
 static struct kmem_cache *btrfs_inode_cachep;
 struct kmem_cache *btrfs_trans_handle_cachep;
 struct kmem_cache *btrfs_transaction_cachep;
@@ -1537,21 +2305,14 @@ static struct inode *btrfs_alloc_inode(struct super_block *sb)
 	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_data.nrpages);
 
-	ei->magic = 0;
-	ei->magic2 = 0;
 	kmem_cache_free(btrfs_inode_cachep, BTRFS_I(inode));
 }
 
@@ -1616,6 +2377,30 @@ static int btrfs_get_sb(struct file_system_type *fs_type,
 			   btrfs_fill_super, mnt);
 }
 
+
+static int btrfs_getattr(struct vfsmount *mnt,
+			 struct dentry *dentry, struct kstat *stat)
+{
+	struct inode *inode = dentry->d_inode;
+	generic_fillattr(inode, stat);
+	stat->blksize = 256 * 1024;
+	return 0;
+}
+
+static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+	struct btrfs_root *root = btrfs_sb(dentry->d_sb);
+	struct btrfs_super_block *disk_super = root->fs_info->disk_super;
+
+	buf->f_namelen = BTRFS_NAME_LEN;
+	buf->f_blocks = btrfs_super_total_blocks(disk_super);
+	buf->f_bfree = buf->f_blocks - btrfs_super_blocks_used(disk_super);
+	buf->f_bavail = buf->f_bfree;
+	buf->f_bsize = dentry->d_sb->s_blocksize;
+	buf->f_type = BTRFS_SUPER_MAGIC;
+	return 0;
+}
+
 static struct file_system_type btrfs_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "btrfs",
@@ -1625,15 +2410,16 @@ static struct file_system_type btrfs_fs_type = {
 };
 
 static struct super_operations btrfs_super_ops = {
-	.statfs		= simple_statfs,
 	.delete_inode	= btrfs_delete_inode,
 	.put_super	= btrfs_put_super,
 	.read_inode	= btrfs_read_locked_inode,
 	.write_super	= btrfs_write_super,
 	.sync_fs	= btrfs_sync_fs,
 	.write_inode	= btrfs_write_inode,
+	.dirty_inode	= btrfs_dirty_inode,
 	.alloc_inode	= btrfs_alloc_inode,
 	.destroy_inode	= btrfs_destroy_inode,
+	.statfs		= btrfs_statfs,
 };
 
 static struct inode_operations btrfs_dir_inode_operations = {
@@ -1644,15 +2430,19 @@ static struct inode_operations btrfs_dir_inode_operations = {
 	.rmdir		= btrfs_rmdir,
 };
 
+static struct inode_operations btrfs_dir_ro_inode_operations = {
+	.lookup		= btrfs_lookup,
+};
+
 static struct file_operations btrfs_dir_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= generic_read_dir,
 	.readdir	= btrfs_readdir,
+	.ioctl		= btrfs_ioctl,
 };
 
 static struct address_space_operations btrfs_aops = {
 	.readpage	= btrfs_readpage,
-	// .readpages	= btrfs_readpages,
 	.writepage	= btrfs_writepage,
 	.sync_page	= block_sync_page,
 	.prepare_write	= btrfs_prepare_write,
@@ -1661,15 +2451,18 @@ static struct address_space_operations btrfs_aops = {
 
 static struct inode_operations btrfs_file_inode_operations = {
 	.truncate	= btrfs_truncate,
+	.getattr	= btrfs_getattr,
 };
 
 static struct file_operations btrfs_file_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= do_sync_read,
-	.aio_read       = generic_file_aio_read,
-	.write		= btrfs_file_inline_write,
+	.aio_read       = btrfs_file_aio_read,
+	.write		= btrfs_file_write,
 	.mmap		= generic_file_mmap,
 	.open		= generic_file_open,
+	.ioctl		= btrfs_ioctl,
+	.fsync		= btrfs_sync_file,
 };
 
 static int __init init_btrfs_fs(void)
@@ -1679,13 +2472,21 @@ static int __init init_btrfs_fs(void)
 	err = init_inodecache();
 	if (err)
 		return err;
+	kset_set_kset_s(&btrfs_subsys, fs_subsys);
+	err = subsystem_register(&btrfs_subsys);
+	if (err)
+		goto out;
 	return register_filesystem(&btrfs_fs_type);
+out:
+	destroy_inodecache();
+	return err;
 }
 
 static void __exit exit_btrfs_fs(void)
 {
 	destroy_inodecache();
 	unregister_filesystem(&btrfs_fs_type);
+	subsystem_unregister(&btrfs_subsys);
 	printk("btrfs unloaded\n");
 }