16 files changed, 2074 insertions, 91 deletions

diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index 31610ea73ae..a8411c22313 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -7,4 +7,4 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
 	   extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \
 	   extent_io.o volumes.o async-thread.o ioctl.o locking.o orphan.o \
 	   export.o tree-log.o acl.o free-space-cache.o zlib.o lzo.o \
-	   compression.o delayed-ref.o relocation.o
+	   compression.o delayed-ref.o relocation.o delayed-inode.o
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h
index 8842a4195f9..d0b0e43a6a8 100644
--- a/fs/btrfs/btrfs_inode.h
+++ b/fs/btrfs/btrfs_inode.h
@@ -22,6 +22,7 @@
 #include "extent_map.h"
 #include "extent_io.h"
 #include "ordered-data.h"
+#include "delayed-inode.h"
 
 /* in memory btrfs inode */
 struct btrfs_inode {
@@ -158,9 +159,13 @@ struct btrfs_inode {
 	 */
 	unsigned force_compress:4;
 
+	struct btrfs_delayed_node *delayed_node;
+
 	struct inode vfs_inode;
 };
 
+extern unsigned char btrfs_filetype_table[];
+
 static inline struct btrfs_inode *BTRFS_I(struct inode *inode)
 {
 	return container_of(inode, struct btrfs_inode, vfs_inode);
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 84d7ca1fe0b..2736b6b2ff5 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -38,11 +38,6 @@ static int balance_node_right(struct btrfs_trans_handle *trans,
 			      struct extent_buffer *src_buf);
 static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 		   struct btrfs_path *path, int level, int slot);
-static int setup_items_for_insert(struct btrfs_trans_handle *trans,
-			struct btrfs_root *root, struct btrfs_path *path,
-			struct btrfs_key *cpu_key, u32 *data_size,
-			u32 total_data, u32 total_size, int nr);
-
 
 struct btrfs_path *btrfs_alloc_path(void)
 {
@@ -3559,11 +3554,10 @@ out:
  * to save stack depth by doing the bulk of the work in a function
  * that doesn't call btrfs_search_slot
  */
-static noinline_for_stack int
-setup_items_for_insert(struct btrfs_trans_handle *trans,
-		      struct btrfs_root *root, struct btrfs_path *path,
-		      struct btrfs_key *cpu_key, u32 *data_size,
-		      u32 total_data, u32 total_size, int nr)
+int setup_items_for_insert(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root, struct btrfs_path *path,
+			   struct btrfs_key *cpu_key, u32 *data_size,
+			   u32 total_data, u32 total_size, int nr)
 {
 	struct btrfs_item *item;
 	int i;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 11a103db286..529c157000b 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -870,6 +870,7 @@ struct btrfs_block_group_cache {
 struct reloc_control;
 struct btrfs_device;
 struct btrfs_fs_devices;
+struct btrfs_delayed_root;
 struct btrfs_fs_info {
 	u8 fsid[BTRFS_FSID_SIZE];
 	u8 chunk_tree_uuid[BTRFS_UUID_SIZE];
@@ -896,7 +897,10 @@ struct btrfs_fs_info {
 	/* logical->physical extent mapping */
 	struct btrfs_mapping_tree mapping_tree;
 
-	/* block reservation for extent, checksum and root tree */
+	/*
+	 * block reservation for extent, checksum, root tree and
+	 * delayed dir index item
+	 */
 	struct btrfs_block_rsv global_block_rsv;
 	/* block reservation for delay allocation */
 	struct btrfs_block_rsv delalloc_block_rsv;
@@ -1023,6 +1027,7 @@ struct btrfs_fs_info {
 	 * for the sys_munmap function call path
 	 */
 	struct btrfs_workers fixup_workers;
+	struct btrfs_workers delayed_workers;
 	struct task_struct *transaction_kthread;
 	struct task_struct *cleaner_kthread;
 	int thread_pool_size;
@@ -1080,6 +1085,8 @@ struct btrfs_fs_info {
 
 	/* filesystem state */
 	u64 fs_state;
+
+	struct btrfs_delayed_root *delayed_root;
 };
 
 /*
@@ -1173,6 +1180,11 @@ struct btrfs_root {
 	struct rb_root inode_tree;
 
 	/*
+	 * radix tree that keeps track of delayed nodes of every inode,
+	 * protected by inode_lock
+	 */
+	struct radix_tree_root delayed_nodes_tree;
+	/*
 	 * right now this just gets used so that a root has its own devid
 	 * for stat.  It may be used for more later
 	 */
@@ -2110,6 +2122,13 @@ static inline bool btrfs_mixed_space_info(struct btrfs_space_info *space_info)
 }
 
 /* extent-tree.c */
+static inline u64 btrfs_calc_trans_metadata_size(struct btrfs_root *root,
+						 int num_items)
+{
+	return (root->leafsize + root->nodesize * (BTRFS_MAX_LEVEL - 1)) *
+		3 * num_items;
+}
+
 void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
 			   struct btrfs_root *root, unsigned long count);
@@ -2305,6 +2324,8 @@ 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_set_path_blocking(struct btrfs_path *p);
+void btrfs_clear_path_blocking(struct btrfs_path *p,
+			       struct extent_buffer *held);
 void btrfs_unlock_up_safe(struct btrfs_path *p, int level);
 
 int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
@@ -2316,6 +2337,10 @@ static inline int btrfs_del_item(struct btrfs_trans_handle *trans,
 	return btrfs_del_items(trans, root, path, path->slots[0], 1);
 }
 
+int setup_items_for_insert(struct btrfs_trans_handle *trans,
+			   struct btrfs_root *root, struct btrfs_path *path,
+			   struct btrfs_key *cpu_key, u32 *data_size,
+			   u32 total_data, u32 total_size, int nr);
 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
 		      *root, struct btrfs_key *key, void *data, u32 data_size);
 int btrfs_insert_some_items(struct btrfs_trans_handle *trans,
@@ -2379,7 +2404,7 @@ void btrfs_check_and_init_root_item(struct btrfs_root_item *item);
 /* dir-item.c */
 int btrfs_insert_dir_item(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *root, const char *name,
-			  int name_len, u64 dir,
+			  int name_len, struct inode *dir,
 			  struct btrfs_key *location, u8 type, u64 index);
 struct btrfs_dir_item *btrfs_lookup_dir_item(struct btrfs_trans_handle *trans,
 					     struct btrfs_root *root,
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
new file mode 100644
index 00000000000..95485318f00
--- /dev/null
+++ b/fs/btrfs/delayed-inode.c
@@ -0,0 +1,1694 @@
+/*
+ * Copyright (C) 2011 Fujitsu.  All rights reserved.
+ * Written by Miao Xie <miaox@cn.fujitsu.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#include <linux/slab.h>
+#include "delayed-inode.h"
+#include "disk-io.h"
+#include "transaction.h"
+
+#define BTRFS_DELAYED_WRITEBACK		400
+#define BTRFS_DELAYED_BACKGROUND	100
+
+static struct kmem_cache *delayed_node_cache;
+
+int __init btrfs_delayed_inode_init(void)
+{
+	delayed_node_cache = kmem_cache_create("delayed_node",
+					sizeof(struct btrfs_delayed_node),
+					0,
+					SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+					NULL);
+	if (!delayed_node_cache)
+		return -ENOMEM;
+	return 0;
+}
+
+void btrfs_delayed_inode_exit(void)
+{
+	if (delayed_node_cache)
+		kmem_cache_destroy(delayed_node_cache);
+}
+
+static inline void btrfs_init_delayed_node(
+				struct btrfs_delayed_node *delayed_node,
+				struct btrfs_root *root, u64 inode_id)
+{
+	delayed_node->root = root;
+	delayed_node->inode_id = inode_id;
+	atomic_set(&delayed_node->refs, 0);
+	delayed_node->count = 0;
+	delayed_node->in_list = 0;
+	delayed_node->inode_dirty = 0;
+	delayed_node->ins_root = RB_ROOT;
+	delayed_node->del_root = RB_ROOT;
+	mutex_init(&delayed_node->mutex);
+	delayed_node->index_cnt = 0;
+	INIT_LIST_HEAD(&delayed_node->n_list);
+	INIT_LIST_HEAD(&delayed_node->p_list);
+	delayed_node->bytes_reserved = 0;
+}
+
+static inline int btrfs_is_continuous_delayed_item(
+					struct btrfs_delayed_item *item1,
+					struct btrfs_delayed_item *item2)
+{
+	if (item1->key.type == BTRFS_DIR_INDEX_KEY &&
+	    item1->key.objectid == item2->key.objectid &&
+	    item1->key.type == item2->key.type &&
+	    item1->key.offset + 1 == item2->key.offset)
+		return 1;
+	return 0;
+}
+
+static inline struct btrfs_delayed_root *btrfs_get_delayed_root(
+							struct btrfs_root *root)
+{
+	return root->fs_info->delayed_root;
+}
+
+static struct btrfs_delayed_node *btrfs_get_or_create_delayed_node(
+							struct inode *inode)
+{
+	struct btrfs_delayed_node *node;
+	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
+	struct btrfs_root *root = btrfs_inode->root;
+	int ret;
+
+again:
+	node = ACCESS_ONCE(btrfs_inode->delayed_node);
+	if (node) {
+		atomic_inc(&node->refs);	/* can be accessed */
+		return node;
+	}
+
+	spin_lock(&root->inode_lock);
+	node = radix_tree_lookup(&root->delayed_nodes_tree, inode->i_ino);
+	if (node) {
+		if (btrfs_inode->delayed_node) {
+			spin_unlock(&root->inode_lock);
+			goto again;
+		}
+		btrfs_inode->delayed_node = node;
+		atomic_inc(&node->refs);	/* can be accessed */
+		atomic_inc(&node->refs);	/* cached in the inode */
+		spin_unlock(&root->inode_lock);
+		return node;
+	}
+	spin_unlock(&root->inode_lock);
+
+	node = kmem_cache_alloc(delayed_node_cache, GFP_NOFS);
+	if (!node)
+		return ERR_PTR(-ENOMEM);
+	btrfs_init_delayed_node(node, root, inode->i_ino);
+
+	atomic_inc(&node->refs);	/* cached in the btrfs inode */
+	atomic_inc(&node->refs);	/* can be accessed */
+
+	ret = radix_tree_preload(GFP_NOFS & ~__GFP_HIGHMEM);
+	if (ret) {
+		kmem_cache_free(delayed_node_cache, node);
+		return ERR_PTR(ret);
+	}
+
+	spin_lock(&root->inode_lock);
+	ret = radix_tree_insert(&root->delayed_nodes_tree, inode->i_ino, node);
+	if (ret == -EEXIST) {
+		kmem_cache_free(delayed_node_cache, node);
+		spin_unlock(&root->inode_lock);
+		radix_tree_preload_end();
+		goto again;
+	}
+	btrfs_inode->delayed_node = node;
+	spin_unlock(&root->inode_lock);
+	radix_tree_preload_end();
+
+	return node;
+}
+
+/*
+ * Call it when holding delayed_node->mutex
+ *
+ * If mod = 1, add this node into the prepared list.
+ */
+static void btrfs_queue_delayed_node(struct btrfs_delayed_root *root,
+				     struct btrfs_delayed_node *node,
+				     int mod)
+{
+	spin_lock(&root->lock);
+	if (node->in_list) {
+		if (!list_empty(&node->p_list))
+			list_move_tail(&node->p_list, &root->prepare_list);
+		else if (mod)
+			list_add_tail(&node->p_list, &root->prepare_list);
+	} else {
+		list_add_tail(&node->n_list, &root->node_list);
+		list_add_tail(&node->p_list, &root->prepare_list);
+		atomic_inc(&node->refs);	/* inserted into list */
+		root->nodes++;
+		node->in_list = 1;
+	}
+	spin_unlock(&root->lock);
+}
+
+/* Call it when holding delayed_node->mutex */
+static void btrfs_dequeue_delayed_node(struct btrfs_delayed_root *root,
+				       struct btrfs_delayed_node *node)
+{
+	spin_lock(&root->lock);
+	if (node->in_list) {
+		root->nodes--;
+		atomic_dec(&node->refs);	/* not in the list */
+		list_del_init(&node->n_list);
+		if (!list_empty(&node->p_list))
+			list_del_init(&node->p_list);
+		node->in_list = 0;
+	}
+	spin_unlock(&root->lock);
+}
+
+struct btrfs_delayed_node *btrfs_first_delayed_node(
+			struct btrfs_delayed_root *delayed_root)
+{
+	struct list_head *p;
+	struct btrfs_delayed_node *node = NULL;
+
+	spin_lock(&delayed_root->lock);
+	if (list_empty(&delayed_root->node_list))
+		goto out;
+
+	p = delayed_root->node_list.next;
+	node = list_entry(p, struct btrfs_delayed_node, n_list);
+	atomic_inc(&node->refs);
+out:
+	spin_unlock(&delayed_root->lock);
+
+	return node;
+}
+
+struct btrfs_delayed_node *btrfs_next_delayed_node(
+						struct btrfs_delayed_node *node)
+{
+	struct btrfs_delayed_root *delayed_root;
+	struct list_head *p;
+	struct btrfs_delayed_node *next = NULL;
+
+	delayed_root = node->root->fs_info->delayed_root;
+	spin_lock(&delayed_root->lock);
+	if (!node->in_list) {	/* not in the list */
+		if (list_empty(&delayed_root->node_list))
+			goto out;
+		p = delayed_root->node_list.next;
+	} else if (list_is_last(&node->n_list, &delayed_root->node_list))
+		goto out;
+	else
+		p = node->n_list.next;
+
+	next = list_entry(p, struct btrfs_delayed_node, n_list);
+	atomic_inc(&next->refs);
+out:
+	spin_unlock(&delayed_root->lock);
+
+	return next;
+}
+
+static void __btrfs_release_delayed_node(
+				struct btrfs_delayed_node *delayed_node,
+				int mod)
+{
+	struct btrfs_delayed_root *delayed_root;
+
+	if (!delayed_node)
+		return;
+
+	delayed_root = delayed_node->root->fs_info->delayed_root;
+
+	mutex_lock(&delayed_node->mutex);
+	if (delayed_node->count)
+		btrfs_queue_delayed_node(delayed_root, delayed_node, mod);
+	else
+		btrfs_dequeue_delayed_node(delayed_root, delayed_node);
+	mutex_unlock(&delayed_node->mutex);
+
+	if (atomic_dec_and_test(&delayed_node->refs)) {
+		struct btrfs_root *root = delayed_node->root;
+		spin_lock(&root->inode_lock);
+		if (atomic_read(&delayed_node->refs) == 0) {
+			radix_tree_delete(&root->delayed_nodes_tree,
+					  delayed_node->inode_id);
+			kmem_cache_free(delayed_node_cache, delayed_node);
+		}
+		spin_unlock(&root->inode_lock);
+	}
+}
+
+static inline void btrfs_release_delayed_node(struct btrfs_delayed_node *node)
+{
+	__btrfs_release_delayed_node(node, 0);
+}
+
+struct btrfs_delayed_node *btrfs_first_prepared_delayed_node(
+					struct btrfs_delayed_root *delayed_root)
+{
+	struct list_head *p;
+	struct btrfs_delayed_node *node = NULL;
+
+	spin_lock(&delayed_root->lock);
+	if (list_empty(&delayed_root->prepare_list))
+		goto out;
+
+	p = delayed_root->prepare_list.next;
+	list_del_init(p);
+	node = list_entry(p, struct btrfs_delayed_node, p_list);
+	atomic_inc(&node->refs);
+out:
+	spin_unlock(&delayed_root->lock);
+
+	return node;
+}
+
+static inline void btrfs_release_prepared_delayed_node(
+					struct btrfs_delayed_node *node)
+{
+	__btrfs_release_delayed_node(node, 1);
+}
+
+struct btrfs_delayed_item *btrfs_alloc_delayed_item(u32 data_len)
+{
+	struct btrfs_delayed_item *item;
+	item = kmalloc(sizeof(*item) + data_len, GFP_NOFS);
+	if (item) {
+		item->data_len = data_len;
+		item->ins_or_del = 0;
+		item->bytes_reserved = 0;
+		item->block_rsv = NULL;
+		item->delayed_node = NULL;
+		atomic_set(&item->refs, 1);
+	}
+	return item;
+}
+
+/*
+ * __btrfs_lookup_delayed_item - look up the delayed item by key
+ * @delayed_node: pointer to the delayed node
+ * @key:	  the key to look up
+ * @prev:	  used to store the prev item if the right item isn't found
+ * @next:	  used to store the next item if the right item isn't found
+ *
+ * Note: if we don't find the right item, we will return the prev item and
+ * the next item.
+ */
+static struct btrfs_delayed_item *__btrfs_lookup_delayed_item(
+				struct rb_root *root,
+				struct btrfs_key *key,
+				struct btrfs_delayed_item **prev,
+				struct btrfs_delayed_item **next)
+{
+	struct rb_node *node, *prev_node = NULL;
+	struct btrfs_delayed_item *delayed_item = NULL;
+	int ret = 0;
+
+	node = root->rb_node;
+
+	while (node) {
+		delayed_item = rb_entry(node, struct btrfs_delayed_item,
+					rb_node);
+		prev_node = node;
+		ret = btrfs_comp_cpu_keys(&delayed_item->key, key);
+		if (ret < 0)
+			node = node->rb_right;
+		else if (ret > 0)
+			node = node->rb_left;
+		else
+			return delayed_item;
+	}
+
+	if (prev) {
+		if (!prev_node)
+			*prev = NULL;
+		else if (ret < 0)
+			*prev = delayed_item;
+		else if ((node = rb_prev(prev_node)) != NULL) {
+			*prev = rb_entry(node, struct btrfs_delayed_item,
+					 rb_node);
+		} else
+			*prev = NULL;
+	}
+
+	if (next) {
+		if (!prev_node)
+			*next = NULL;
+		else if (ret > 0)
+			*next = delayed_item;
+		else if ((node = rb_next(prev_node)) != NULL) {
+			*next = rb_entry(node, struct btrfs_delayed_item,
+					 rb_node);
+		} else
+			*next = NULL;
+	}
+	return NULL;
+}
+
+struct btrfs_delayed_item *__btrfs_lookup_delayed_insertion_item(
+					struct btrfs_delayed_node *delayed_node,
+					struct btrfs_key *key)
+{
+	struct btrfs_delayed_item *item;
+
+	item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
+					   NULL, NULL);
+	return item;
+}
+
+struct btrfs_delayed_item *__btrfs_lookup_delayed_deletion_item(
+					struct btrfs_delayed_node *delayed_node,
+					struct btrfs_key *key)
+{
+	struct btrfs_delayed_item *item;
+
+	item = __btrfs_lookup_delayed_item(&delayed_node->del_root, key,
+					   NULL, NULL);
+	return item;
+}
+
+struct btrfs_delayed_item *__btrfs_search_delayed_insertion_item(
+					struct btrfs_delayed_node *delayed_node,
+					struct btrfs_key *key)
+{
+	struct btrfs_delayed_item *item, *next;
+
+	item = __btrfs_lookup_delayed_item(&delayed_node->ins_root, key,
+					   NULL, &next);
+	if (!item)
+		item = next;
+
+	return item;
+}
+
+struct btrfs_delayed_item *__btrfs_search_delayed_deletion_item(
+					struct btrfs_delayed_node *delayed_node,
+					struct btrfs_key *key)
+{
+	struct btrfs_delayed_item *item, *next;
+
+	item = __btrfs_lookup_delayed_item(&delayed_node->del_root, key,
+					   NULL, &next);
+	if (!item)
+		item = next;
+
+	return item;
+}
+
+static int __btrfs_add_delayed_item(struct btrfs_delayed_node *delayed_node,
+				    struct btrfs_delayed_item *ins,
+				    int action)
+{
+	struct rb_node **p, *node;
+	struct rb_node *parent_node = NULL;
+	struct rb_root *root;
+	struct btrfs_delayed_item *item;
+	int cmp;
+
+	if (action == BTRFS_DELAYED_INSERTION_ITEM)
+		root = &delayed_node->ins_root;
+	else if (action == BTRFS_DELAYED_DELETION_ITEM)
+		root = &delayed_node->del_root;
+	else
+		BUG();
+	p = &root->rb_node;
+	node = &ins->rb_node;
+
+	while (*p) {
+		parent_node = *p;
+		item = rb_entry(parent_node, struct btrfs_delayed_item,
+				 rb_node);
+
+		cmp = btrfs_comp_cpu_keys(&item->key, &ins->key);
+		if (cmp < 0)
+			p = &(*p)->rb_right;
+		else if (cmp > 0)
+			p = &(*p)->rb_left;
+		else
+			return -EEXIST;
+	}
+
+	rb_link_node(node, parent_node, p);
+	rb_insert_color(node, root);
+	ins->delayed_node = delayed_node;
+	ins->ins_or_del = action;
+
+	if (ins->key.type == BTRFS_DIR_INDEX_KEY &&
+	    action == BTRFS_DELAYED_INSERTION_ITEM &&
+	    ins->key.offset >= delayed_node->index_cnt)
+			delayed_node->index_cnt = ins->key.offset + 1;
+
+	delayed_node->count++;
+	atomic_inc(&delayed_node->root->fs_info->delayed_root->items);
+	return 0;
+}
+
+static int __btrfs_add_delayed_insertion_item(struct btrfs_delayed_node *node,
+					      struct btrfs_delayed_item *item)
+{
+	return __btrfs_add_delayed_item(node, item,
+					BTRFS_DELAYED_INSERTION_ITEM);
+}
+
+static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node,
+					     struct btrfs_delayed_item *item)
+{
+	return __btrfs_add_delayed_item(node, item,
+					BTRFS_DELAYED_DELETION_ITEM);
+}
+
+static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item)
+{
+	struct rb_root *root;
+	struct btrfs_delayed_root *delayed_root;
+
+	delayed_root = delayed_item->delayed_node->root->fs_info->delayed_root;
+
+	BUG_ON(!delayed_root);
+	BUG_ON(delayed_item->ins_or_del != BTRFS_DELAYED_DELETION_ITEM &&
+	       delayed_item->ins_or_del != BTRFS_DELAYED_INSERTION_ITEM);
+
+	if (delayed_item->ins_or_del == BTRFS_DELAYED_INSERTION_ITEM)
+		root = &delayed_item->delayed_node->ins_root;
+	else
+		root = &delayed_item->delayed_node->del_root;
+
+	rb_erase(&delayed_item->rb_node, root);
+	delayed_item->delayed_node->count--;
+	atomic_dec(&delayed_root->items);
+	if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND &&
+	    waitqueue_active(&delayed_root->wait))
+		wake_up(&delayed_root->wait);
+}
+
+static void btrfs_release_delayed_item(struct btrfs_delayed_item *item)
+{
+	if (item) {
+		__btrfs_remove_delayed_item(item);
+		if (atomic_dec_and_test(&item->refs))
+			kfree(item);
+	}
+}
+
+struct btrfs_delayed_item *__btrfs_first_delayed_insertion_item(
+					struct btrfs_delayed_node *delayed_node)
+{
+	struct rb_node *p;
+	struct btrfs_delayed_item *item = NULL;
+
+	p = rb_first(&delayed_node->ins_root);
+	if (p)
+		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
+
+	return item;
+}
+
+struct btrfs_delayed_item *__btrfs_first_delayed_deletion_item(
+					struct btrfs_delayed_node *delayed_node)
+{
+	struct rb_node *p;
+	struct btrfs_delayed_item *item = NULL;
+
+	p = rb_first(&delayed_node->del_root);
+	if (p)
+		item = rb_entry(p, struct btrfs_delayed_item, rb_node);
+
+	return item;
+}
+
+struct btrfs_delayed_item *__btrfs_next_delayed_item(
+						struct btrfs_delayed_item *item)
+{
+	struct rb_node *p;
+	struct btrfs_delayed_item *next = NULL;
+
+	p = rb_next(&item->rb_node);
+	if (p)
+		next = rb_entry(p, struct btrfs_delayed_item, rb_node);
+
+	return next;
+}
+
+static inline struct btrfs_delayed_node *btrfs_get_delayed_node(
+							struct inode *inode)
+{
+	struct btrfs_inode *btrfs_inode = BTRFS_I(inode);
+	struct btrfs_delayed_node *delayed_node;
+
+	delayed_node = btrfs_inode->delayed_node;
+	if (delayed_node)
+		atomic_inc(&delayed_node->refs);
+
+	return delayed_node;
+}
+
+static inline struct btrfs_root *btrfs_get_fs_root(struct btrfs_root *root,
+						   u64 root_id)
+{
+	struct btrfs_key root_key;
+
+	if (root->objectid == root_id)
+		return root;
+
+	root_key.objectid = root_id;
+	root_key.type = BTRFS_ROOT_ITEM_KEY;
+	root_key.offset = (u64)-1;
+	return btrfs_read_fs_root_no_name(root->fs_info, &root_key);
+}
+
+static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
+					       struct btrfs_root *root,
+					       struct btrfs_delayed_item *item)
+{
+	struct btrfs_block_rsv *src_rsv;
+	struct btrfs_block_rsv *dst_rsv;
+	u64 num_bytes;
+	int ret;
+
+	if (!trans->bytes_reserved)
+		return 0;
+
+	src_rsv = trans->block_rsv;
+	dst_rsv = &root->fs_info->global_block_rsv;
+
+	num_bytes = btrfs_calc_trans_metadata_size(root, 1);
+	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
+	if (!ret) {
+		item->bytes_reserved = num_bytes;
+		item->block_rsv = dst_rsv;
+	}
+
+	return ret;
+}
+
+static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
+						struct btrfs_delayed_item *item)
+{
+	if (!item->bytes_reserved)
+		return;
+
+	btrfs_block_rsv_release(root, item->block_rsv,
+				item->bytes_reserved);
+}
+
+static int btrfs_delayed_inode_reserve_metadata(
+					struct btrfs_trans_handle *trans,
+					struct btrfs_root *root,
+					struct btrfs_delayed_node *node)
+{
+	struct btrfs_block_rsv *src_rsv;
+	struct btrfs_block_rsv *dst_rsv;
+	u64 num_bytes;
+	int ret;
+
+	if (!trans->bytes_reserved)
+		return 0;
+
+	src_rsv = trans->block_rsv;
+	dst_rsv = &root->fs_info->global_block_rsv;
+
+	num_bytes = btrfs_calc_trans_metadata_size(root, 1);
+	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes);
+	if (!ret)
+		node->bytes_reserved = num_bytes;
+
+	return ret;
+}
+
+static void btrfs_delayed_inode_release_metadata(struct btrfs_root *root,
+						struct btrfs_delayed_node *node)
+{
+	struct btrfs_block_rsv *rsv;
+
+	if (!node->bytes_reserved)
+		return;
+
+	rsv = &root->fs_info->global_block_rsv;
+	btrfs_block_rsv_release(root, rsv,
+				node->bytes_reserved);
+	node->bytes_reserved = 0;
+}
+
+/*
+ * This helper will insert some continuous items into the same leaf according
+ * to the free space of the leaf.
+ */
+static int btrfs_batch_insert_items(struct btrfs_trans_handle *trans,
+				struct btrfs_root *root,
+				struct btrfs_path *path,
+				struct btrfs_delayed_item *item)
+{
+	struct btrfs_delayed_item *curr, *next;
+	int free_space;
+	int total_data_size = 0, total_size = 0;
+	struct extent_buffer *leaf;
+	char *data_ptr;
+	struct btrfs_key *keys;
+	u32 *data_size;
+	struct list_head head;
+	int slot;
+	int nitems;
+	int i;
+	int ret = 0;
+
+	BUG_ON(!path->nodes[0]);
+
+	leaf = path->nodes[0];
+	free_space = btrfs_leaf_free_space(root, leaf);
+	INIT_LIST_HEAD(&head);
+
+	next = item;
+
+	/*
+	 * count the number of the continuous items that we can insert in batch
+	 */
+	while (total_size + next->data_len + sizeof(struct btrfs_item) <=
+	       free_space) {
+		total_data_size += next->data_len;
+		total_size += next->data_len + sizeof(struct btrfs_item);
+		list_add_tail(&next->tree_list, &head);
+		nitems++;
+
+		curr = next;
+		next = __btrfs_next_delayed_item(curr);
+		if (!next)
+			break;
+
+		if (!btrfs_is_continuous_delayed_item(curr, next))
+			break;
+	}
+
+	if (!nitems) {
+		ret = 0;
+		goto out;
+	}
+
+	/*
+	 * we need allocate some memory space, but it might cause the task
+	 * to sleep, so we set all locked nodes in the path to blocking locks
+	 * first.
+	 */
+	btrfs_set_path_blocking(path);
+
+	keys = kmalloc(sizeof(struct btrfs_key) * nitems, GFP_NOFS);
+	if (!keys) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	data_size = kmalloc(sizeof(u32) * nitems, GFP_NOFS);
+	if (!data_size) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	/* get keys of all the delayed items */
+	i = 0;
+	list_for_each_entry(next, &head, tree_list) {
+		keys[i] = next->key;
+		data_size[i] = next->data_len;
+		i++;
+	}
+
+	/* reset all the locked nodes in the patch to spinning locks. */
+	btrfs_clear_path_blocking(path, NULL);
+
+	/* insert the keys of the items */
+	ret = setup_items_for_insert(trans, root, path, keys, data_size,
+				     total_data_size, total_size, nitems);
+	if (ret)
+		goto error;
+
+	/* insert the dir index items */
+	slot = path->slots[0];
+	list_for_each_entry_safe(curr, next, &head, tree_list) {
+		data_ptr = btrfs_item_ptr(leaf, slot, char);
+		write_extent_buffer(leaf, &curr->data,
+				    (unsigned long)data_ptr,
+				    curr->data_len);
+		slot++;
+
+		btrfs_delayed_item_release_metadata(root, curr);
+
+		list_del(&curr->tree_list);
+		btrfs_release_delayed_item(curr);
+	}
+
+error:
+	kfree(data_size);
+	kfree(keys);
+out:
+	return ret;
+}
+
+/*
+ * This helper can just do simple insertion that needn't extend item for new
+ * data, such as directory name index insertion, inode insertion.
+ */
+static int btrfs_insert_delayed_item(struct btrfs_trans_handle *trans,
+				     struct btrfs_root *root,
+				     struct btrfs_path *path,
+				     struct btrfs_delayed_item *delayed_item)
+{
+	struct extent_buffer *leaf;
+	struct btrfs_item *item;
+	char *ptr;
+	int ret;
+
+	ret = btrfs_insert_empty_item(trans, root, path, &delayed_item->key,
+				      delayed_item->data_len);
+	if (ret < 0 && ret != -EEXIST)
+		return ret;
+
+	leaf = path->nodes[0];
+
+	item = btrfs_item_nr(leaf, path->slots[0]);
+	ptr = btrfs_item_ptr(leaf, path->slots[0], char);
+
+	write_extent_buffer(leaf, delayed_item->data, (unsigned long)ptr,
+			    delayed_item->data_len);
+	btrfs_mark_buffer_dirty(leaf);
+
+	btrfs_delayed_item_release_metadata(root, delayed_item);
+	return 0;
+}
+
+/*
+ * we insert an item first, then if there are some continuous items, we try
+ * to insert those items into the same leaf.
+ */
+static int btrfs_insert_delayed_items(struct btrfs_trans_handle *trans,
+				      struct btrfs_path *path,
+				      struct btrfs_root *root,
+				      struct btrfs_delayed_node *node)
+{
+	struct btrfs_delayed_item *curr, *prev;
+	int ret = 0;
+
+do_again:
+	mutex_lock(&node->mutex);
+	curr = __btrfs_first_delayed_insertion_item(node);
+	if (!curr)
+		goto insert_end;
+
+	ret = btrfs_insert_delayed_item(trans, root, path, curr);
+	if (ret < 0) {
+		btrfs_release_path(root, path);
+		goto insert_end;
+	}
+
+	prev = curr;
+	curr = __btrfs_next_delayed_item(prev);
+	if (curr && btrfs_is_continuous_delayed_item(prev, curr)) {
+		/* insert the continuous items into the same leaf */
+		path->slots[0]++;
+		btrfs_batch_insert_items(trans, root, path, curr);
+	}
+	btrfs_release_delayed_item(prev);
+	btrfs_mark_buffer_dirty(path->nodes[0]);
+
+	btrfs_release_path(root, path);
+	mutex_unlock(&node->mutex);
+	goto do_again;
+
+insert_end:
+	mutex_unlock(&node->mutex);
+	return ret;
+}
+
+static int btrfs_batch_delete_items(struct btrfs_trans_handle *trans,
+				    struct btrfs_root *root,
+				    struct btrfs_path *path,
+				    struct btrfs_delayed_item *item)
+{
+	struct btrfs_delayed_item *curr, *next;
+	struct extent_buffer *leaf;
+	struct btrfs_key key;
+	struct list_head head;
+	int nitems, i, last_item;
+	int ret = 0;
+
+	BUG_ON(!path->nodes[0]);
+
+	leaf = path->nodes[0];
+
+	i = path->slots[0];
+	last_item = btrfs_header_nritems(leaf) - 1;
+	if (i > last_item)
+		return -ENOENT;	/* FIXME: Is errno suitable? */