v4.19.13 snapshot.
diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c
new file mode 100644
index 0000000..9c4bac1
--- /dev/null
+++ b/fs/ext4/inline.c
@@ -0,0 +1,2029 @@
+// SPDX-License-Identifier: LGPL-2.1
+/*
+ * Copyright (c) 2012 Taobao.
+ * Written by Tao Ma <boyu.mt@taobao.com>
+ */
+
+#include <linux/iomap.h>
+#include <linux/fiemap.h>
+#include <linux/iversion.h>
+
+#include "ext4_jbd2.h"
+#include "ext4.h"
+#include "xattr.h"
+#include "truncate.h"
+
+#define EXT4_XATTR_SYSTEM_DATA	"data"
+#define EXT4_MIN_INLINE_DATA_SIZE	((sizeof(__le32) * EXT4_N_BLOCKS))
+#define EXT4_INLINE_DOTDOT_OFFSET	2
+#define EXT4_INLINE_DOTDOT_SIZE		4
+
+static int ext4_get_inline_size(struct inode *inode)
+{
+	if (EXT4_I(inode)->i_inline_off)
+		return EXT4_I(inode)->i_inline_size;
+
+	return 0;
+}
+
+static int get_max_inline_xattr_value_size(struct inode *inode,
+					   struct ext4_iloc *iloc)
+{
+	struct ext4_xattr_ibody_header *header;
+	struct ext4_xattr_entry *entry;
+	struct ext4_inode *raw_inode;
+	int free, min_offs;
+
+	min_offs = EXT4_SB(inode->i_sb)->s_inode_size -
+			EXT4_GOOD_OLD_INODE_SIZE -
+			EXT4_I(inode)->i_extra_isize -
+			sizeof(struct ext4_xattr_ibody_header);
+
+	/*
+	 * We need to subtract another sizeof(__u32) since an in-inode xattr
+	 * needs an empty 4 bytes to indicate the gap between the xattr entry
+	 * and the name/value pair.
+	 */
+	if (!ext4_test_inode_state(inode, EXT4_STATE_XATTR))
+		return EXT4_XATTR_SIZE(min_offs -
+			EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA)) -
+			EXT4_XATTR_ROUND - sizeof(__u32));
+
+	raw_inode = ext4_raw_inode(iloc);
+	header = IHDR(inode, raw_inode);
+	entry = IFIRST(header);
+
+	/* Compute min_offs. */
+	for (; !IS_LAST_ENTRY(entry); entry = EXT4_XATTR_NEXT(entry)) {
+		if (!entry->e_value_inum && entry->e_value_size) {
+			size_t offs = le16_to_cpu(entry->e_value_offs);
+			if (offs < min_offs)
+				min_offs = offs;
+		}
+	}
+	free = min_offs -
+		((void *)entry - (void *)IFIRST(header)) - sizeof(__u32);
+
+	if (EXT4_I(inode)->i_inline_off) {
+		entry = (struct ext4_xattr_entry *)
+			((void *)raw_inode + EXT4_I(inode)->i_inline_off);
+
+		free += EXT4_XATTR_SIZE(le32_to_cpu(entry->e_value_size));
+		goto out;
+	}
+
+	free -= EXT4_XATTR_LEN(strlen(EXT4_XATTR_SYSTEM_DATA));
+
+	if (free > EXT4_XATTR_ROUND)
+		free = EXT4_XATTR_SIZE(free - EXT4_XATTR_ROUND);
+	else
+		free = 0;
+
+out:
+	return free;
+}
+
+/*
+ * Get the maximum size we now can store in an inode.
+ * If we can't find the space for a xattr entry, don't use the space
+ * of the extents since we have no space to indicate the inline data.
+ */
+int ext4_get_max_inline_size(struct inode *inode)
+{
+	int error, max_inline_size;
+	struct ext4_iloc iloc;
+
+	if (EXT4_I(inode)->i_extra_isize == 0)
+		return 0;
+
+	error = ext4_get_inode_loc(inode, &iloc);
+	if (error) {
+		ext4_error_inode(inode, __func__, __LINE__, 0,
+				 "can't get inode location %lu",
+				 inode->i_ino);
+		return 0;
+	}
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	max_inline_size = get_max_inline_xattr_value_size(inode, &iloc);
+	up_read(&EXT4_I(inode)->xattr_sem);
+
+	brelse(iloc.bh);
+
+	if (!max_inline_size)
+		return 0;
+
+	return max_inline_size + EXT4_MIN_INLINE_DATA_SIZE;
+}
+
+/*
+ * this function does not take xattr_sem, which is OK because it is
+ * currently only used in a code path coming form ext4_iget, before
+ * the new inode has been unlocked
+ */
+int ext4_find_inline_data_nolock(struct inode *inode)
+{
+	struct ext4_xattr_ibody_find is = {
+		.s = { .not_found = -ENODATA, },
+	};
+	struct ext4_xattr_info i = {
+		.name_index = EXT4_XATTR_INDEX_SYSTEM,
+		.name = EXT4_XATTR_SYSTEM_DATA,
+	};
+	int error;
+
+	if (EXT4_I(inode)->i_extra_isize == 0)
+		return 0;
+
+	error = ext4_get_inode_loc(inode, &is.iloc);
+	if (error)
+		return error;
+
+	error = ext4_xattr_ibody_find(inode, &i, &is);
+	if (error)
+		goto out;
+
+	if (!is.s.not_found) {
+		if (is.s.here->e_value_inum) {
+			EXT4_ERROR_INODE(inode, "inline data xattr refers "
+					 "to an external xattr inode");
+			error = -EFSCORRUPTED;
+			goto out;
+		}
+		EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
+					(void *)ext4_raw_inode(&is.iloc));
+		EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
+				le32_to_cpu(is.s.here->e_value_size);
+		ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+	}
+out:
+	brelse(is.iloc.bh);
+	return error;
+}
+
+static int ext4_read_inline_data(struct inode *inode, void *buffer,
+				 unsigned int len,
+				 struct ext4_iloc *iloc)
+{
+	struct ext4_xattr_entry *entry;
+	struct ext4_xattr_ibody_header *header;
+	int cp_len = 0;
+	struct ext4_inode *raw_inode;
+
+	if (!len)
+		return 0;
+
+	BUG_ON(len > EXT4_I(inode)->i_inline_size);
+
+	cp_len = len < EXT4_MIN_INLINE_DATA_SIZE ?
+			len : EXT4_MIN_INLINE_DATA_SIZE;
+
+	raw_inode = ext4_raw_inode(iloc);
+	memcpy(buffer, (void *)(raw_inode->i_block), cp_len);
+
+	len -= cp_len;
+	buffer += cp_len;
+
+	if (!len)
+		goto out;
+
+	header = IHDR(inode, raw_inode);
+	entry = (struct ext4_xattr_entry *)((void *)raw_inode +
+					    EXT4_I(inode)->i_inline_off);
+	len = min_t(unsigned int, len,
+		    (unsigned int)le32_to_cpu(entry->e_value_size));
+
+	memcpy(buffer,
+	       (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs), len);
+	cp_len += len;
+
+out:
+	return cp_len;
+}
+
+/*
+ * write the buffer to the inline inode.
+ * If 'create' is set, we don't need to do the extra copy in the xattr
+ * value since it is already handled by ext4_xattr_ibody_inline_set.
+ * That saves us one memcpy.
+ */
+static void ext4_write_inline_data(struct inode *inode, struct ext4_iloc *iloc,
+				   void *buffer, loff_t pos, unsigned int len)
+{
+	struct ext4_xattr_entry *entry;
+	struct ext4_xattr_ibody_header *header;
+	struct ext4_inode *raw_inode;
+	int cp_len = 0;
+
+	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
+		return;
+
+	BUG_ON(!EXT4_I(inode)->i_inline_off);
+	BUG_ON(pos + len > EXT4_I(inode)->i_inline_size);
+
+	raw_inode = ext4_raw_inode(iloc);
+	buffer += pos;
+
+	if (pos < EXT4_MIN_INLINE_DATA_SIZE) {
+		cp_len = pos + len > EXT4_MIN_INLINE_DATA_SIZE ?
+			 EXT4_MIN_INLINE_DATA_SIZE - pos : len;
+		memcpy((void *)raw_inode->i_block + pos, buffer, cp_len);
+
+		len -= cp_len;
+		buffer += cp_len;
+		pos += cp_len;
+	}
+
+	if (!len)
+		return;
+
+	pos -= EXT4_MIN_INLINE_DATA_SIZE;
+	header = IHDR(inode, raw_inode);
+	entry = (struct ext4_xattr_entry *)((void *)raw_inode +
+					    EXT4_I(inode)->i_inline_off);
+
+	memcpy((void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs) + pos,
+	       buffer, len);
+}
+
+static int ext4_create_inline_data(handle_t *handle,
+				   struct inode *inode, unsigned len)
+{
+	int error;
+	void *value = NULL;
+	struct ext4_xattr_ibody_find is = {
+		.s = { .not_found = -ENODATA, },
+	};
+	struct ext4_xattr_info i = {
+		.name_index = EXT4_XATTR_INDEX_SYSTEM,
+		.name = EXT4_XATTR_SYSTEM_DATA,
+	};
+
+	error = ext4_get_inode_loc(inode, &is.iloc);
+	if (error)
+		return error;
+
+	BUFFER_TRACE(is.iloc.bh, "get_write_access");
+	error = ext4_journal_get_write_access(handle, is.iloc.bh);
+	if (error)
+		goto out;
+
+	if (len > EXT4_MIN_INLINE_DATA_SIZE) {
+		value = EXT4_ZERO_XATTR_VALUE;
+		len -= EXT4_MIN_INLINE_DATA_SIZE;
+	} else {
+		value = "";
+		len = 0;
+	}
+
+	/* Insert the the xttr entry. */
+	i.value = value;
+	i.value_len = len;
+
+	error = ext4_xattr_ibody_find(inode, &i, &is);
+	if (error)
+		goto out;
+
+	BUG_ON(!is.s.not_found);
+
+	error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
+	if (error) {
+		if (error == -ENOSPC)
+			ext4_clear_inode_state(inode,
+					       EXT4_STATE_MAY_INLINE_DATA);
+		goto out;
+	}
+
+	memset((void *)ext4_raw_inode(&is.iloc)->i_block,
+		0, EXT4_MIN_INLINE_DATA_SIZE);
+
+	EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
+				      (void *)ext4_raw_inode(&is.iloc));
+	EXT4_I(inode)->i_inline_size = len + EXT4_MIN_INLINE_DATA_SIZE;
+	ext4_clear_inode_flag(inode, EXT4_INODE_EXTENTS);
+	ext4_set_inode_flag(inode, EXT4_INODE_INLINE_DATA);
+	get_bh(is.iloc.bh);
+	error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
+
+out:
+	brelse(is.iloc.bh);
+	return error;
+}
+
+static int ext4_update_inline_data(handle_t *handle, struct inode *inode,
+				   unsigned int len)
+{
+	int error;
+	void *value = NULL;
+	struct ext4_xattr_ibody_find is = {
+		.s = { .not_found = -ENODATA, },
+	};
+	struct ext4_xattr_info i = {
+		.name_index = EXT4_XATTR_INDEX_SYSTEM,
+		.name = EXT4_XATTR_SYSTEM_DATA,
+	};
+
+	/* If the old space is ok, write the data directly. */
+	if (len <= EXT4_I(inode)->i_inline_size)
+		return 0;
+
+	error = ext4_get_inode_loc(inode, &is.iloc);
+	if (error)
+		return error;
+
+	error = ext4_xattr_ibody_find(inode, &i, &is);
+	if (error)
+		goto out;
+
+	BUG_ON(is.s.not_found);
+
+	len -= EXT4_MIN_INLINE_DATA_SIZE;
+	value = kzalloc(len, GFP_NOFS);
+	if (!value) {
+		error = -ENOMEM;
+		goto out;
+	}
+
+	error = ext4_xattr_ibody_get(inode, i.name_index, i.name,
+				     value, len);
+	if (error == -ENODATA)
+		goto out;
+
+	BUFFER_TRACE(is.iloc.bh, "get_write_access");
+	error = ext4_journal_get_write_access(handle, is.iloc.bh);
+	if (error)
+		goto out;
+
+	/* Update the xttr entry. */
+	i.value = value;
+	i.value_len = len;
+
+	error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
+	if (error)
+		goto out;
+
+	EXT4_I(inode)->i_inline_off = (u16)((void *)is.s.here -
+				      (void *)ext4_raw_inode(&is.iloc));
+	EXT4_I(inode)->i_inline_size = EXT4_MIN_INLINE_DATA_SIZE +
+				le32_to_cpu(is.s.here->e_value_size);
+	ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+	get_bh(is.iloc.bh);
+	error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
+
+out:
+	kfree(value);
+	brelse(is.iloc.bh);
+	return error;
+}
+
+static int ext4_prepare_inline_data(handle_t *handle, struct inode *inode,
+				    unsigned int len)
+{
+	int ret, size, no_expand;
+	struct ext4_inode_info *ei = EXT4_I(inode);
+
+	if (!ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA))
+		return -ENOSPC;
+
+	size = ext4_get_max_inline_size(inode);
+	if (size < len)
+		return -ENOSPC;
+
+	ext4_write_lock_xattr(inode, &no_expand);
+
+	if (ei->i_inline_off)
+		ret = ext4_update_inline_data(handle, inode, len);
+	else
+		ret = ext4_create_inline_data(handle, inode, len);
+
+	ext4_write_unlock_xattr(inode, &no_expand);
+	return ret;
+}
+
+static int ext4_destroy_inline_data_nolock(handle_t *handle,
+					   struct inode *inode)
+{
+	struct ext4_inode_info *ei = EXT4_I(inode);
+	struct ext4_xattr_ibody_find is = {
+		.s = { .not_found = 0, },
+	};
+	struct ext4_xattr_info i = {
+		.name_index = EXT4_XATTR_INDEX_SYSTEM,
+		.name = EXT4_XATTR_SYSTEM_DATA,
+		.value = NULL,
+		.value_len = 0,
+	};
+	int error;
+
+	if (!ei->i_inline_off)
+		return 0;
+
+	error = ext4_get_inode_loc(inode, &is.iloc);
+	if (error)
+		return error;
+
+	error = ext4_xattr_ibody_find(inode, &i, &is);
+	if (error)
+		goto out;
+
+	BUFFER_TRACE(is.iloc.bh, "get_write_access");
+	error = ext4_journal_get_write_access(handle, is.iloc.bh);
+	if (error)
+		goto out;
+
+	error = ext4_xattr_ibody_inline_set(handle, inode, &i, &is);
+	if (error)
+		goto out;
+
+	memset((void *)ext4_raw_inode(&is.iloc)->i_block,
+		0, EXT4_MIN_INLINE_DATA_SIZE);
+	memset(ei->i_data, 0, EXT4_MIN_INLINE_DATA_SIZE);
+
+	if (ext4_has_feature_extents(inode->i_sb)) {
+		if (S_ISDIR(inode->i_mode) ||
+		    S_ISREG(inode->i_mode) || S_ISLNK(inode->i_mode)) {
+			ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
+			ext4_ext_tree_init(handle, inode);
+		}
+	}
+	ext4_clear_inode_flag(inode, EXT4_INODE_INLINE_DATA);
+
+	get_bh(is.iloc.bh);
+	error = ext4_mark_iloc_dirty(handle, inode, &is.iloc);
+
+	EXT4_I(inode)->i_inline_off = 0;
+	EXT4_I(inode)->i_inline_size = 0;
+	ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+out:
+	brelse(is.iloc.bh);
+	if (error == -ENODATA)
+		error = 0;
+	return error;
+}
+
+static int ext4_read_inline_page(struct inode *inode, struct page *page)
+{
+	void *kaddr;
+	int ret = 0;
+	size_t len;
+	struct ext4_iloc iloc;
+
+	BUG_ON(!PageLocked(page));
+	BUG_ON(!ext4_has_inline_data(inode));
+	BUG_ON(page->index);
+
+	if (!EXT4_I(inode)->i_inline_off) {
+		ext4_warning(inode->i_sb, "inode %lu doesn't have inline data.",
+			     inode->i_ino);
+		goto out;
+	}
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		goto out;
+
+	len = min_t(size_t, ext4_get_inline_size(inode), i_size_read(inode));
+	kaddr = kmap_atomic(page);
+	ret = ext4_read_inline_data(inode, kaddr, len, &iloc);
+	flush_dcache_page(page);
+	kunmap_atomic(kaddr);
+	zero_user_segment(page, len, PAGE_SIZE);
+	SetPageUptodate(page);
+	brelse(iloc.bh);
+
+out:
+	return ret;
+}
+
+int ext4_readpage_inline(struct inode *inode, struct page *page)
+{
+	int ret = 0;
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		up_read(&EXT4_I(inode)->xattr_sem);
+		return -EAGAIN;
+	}
+
+	/*
+	 * Current inline data can only exist in the 1st page,
+	 * So for all the other pages, just set them uptodate.
+	 */
+	if (!page->index)
+		ret = ext4_read_inline_page(inode, page);
+	else if (!PageUptodate(page)) {
+		zero_user_segment(page, 0, PAGE_SIZE);
+		SetPageUptodate(page);
+	}
+
+	up_read(&EXT4_I(inode)->xattr_sem);
+
+	unlock_page(page);
+	return ret >= 0 ? 0 : ret;
+}
+
+static int ext4_convert_inline_data_to_extent(struct address_space *mapping,
+					      struct inode *inode,
+					      unsigned flags)
+{
+	int ret, needed_blocks, no_expand;
+	handle_t *handle = NULL;
+	int retries = 0, sem_held = 0;
+	struct page *page = NULL;
+	unsigned from, to;
+	struct ext4_iloc iloc;
+
+	if (!ext4_has_inline_data(inode)) {
+		/*
+		 * clear the flag so that no new write
+		 * will trap here again.
+		 */
+		ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+		return 0;
+	}
+
+	needed_blocks = ext4_writepage_trans_blocks(inode);
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		return ret;
+
+retry:
+	handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		handle = NULL;
+		goto out;
+	}
+
+	/* We cannot recurse into the filesystem as the transaction is already
+	 * started */
+	flags |= AOP_FLAG_NOFS;
+
+	page = grab_cache_page_write_begin(mapping, 0, flags);
+	if (!page) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ext4_write_lock_xattr(inode, &no_expand);
+	sem_held = 1;
+	/* If some one has already done this for us, just exit. */
+	if (!ext4_has_inline_data(inode)) {
+		ret = 0;
+		goto out;
+	}
+
+	from = 0;
+	to = ext4_get_inline_size(inode);
+	if (!PageUptodate(page)) {
+		ret = ext4_read_inline_page(inode, page);
+		if (ret < 0)
+			goto out;
+	}
+
+	ret = ext4_destroy_inline_data_nolock(handle, inode);
+	if (ret)
+		goto out;
+
+	if (ext4_should_dioread_nolock(inode)) {
+		ret = __block_write_begin(page, from, to,
+					  ext4_get_block_unwritten);
+	} else
+		ret = __block_write_begin(page, from, to, ext4_get_block);
+
+	if (!ret && ext4_should_journal_data(inode)) {
+		ret = ext4_walk_page_buffers(handle, page_buffers(page),
+					     from, to, NULL,
+					     do_journal_get_write_access);
+	}
+
+	if (ret) {
+		unlock_page(page);
+		put_page(page);
+		page = NULL;
+		ext4_orphan_add(handle, inode);
+		ext4_write_unlock_xattr(inode, &no_expand);
+		sem_held = 0;
+		ext4_journal_stop(handle);
+		handle = NULL;
+		ext4_truncate_failed_write(inode);
+		/*
+		 * If truncate failed early the inode might
+		 * still be on the orphan list; we need to
+		 * make sure the inode is removed from the
+		 * orphan list in that case.
+		 */
+		if (inode->i_nlink)
+			ext4_orphan_del(NULL, inode);
+	}
+
+	if (ret == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
+		goto retry;
+
+	if (page)
+		block_commit_write(page, from, to);
+out:
+	if (page) {
+		unlock_page(page);
+		put_page(page);
+	}
+	if (sem_held)
+		ext4_write_unlock_xattr(inode, &no_expand);
+	if (handle)
+		ext4_journal_stop(handle);
+	brelse(iloc.bh);
+	return ret;
+}
+
+/*
+ * Try to write data in the inode.
+ * If the inode has inline data, check whether the new write can be
+ * in the inode also. If not, create the page the handle, move the data
+ * to the page make it update and let the later codes create extent for it.
+ */
+int ext4_try_to_write_inline_data(struct address_space *mapping,
+				  struct inode *inode,
+				  loff_t pos, unsigned len,
+				  unsigned flags,
+				  struct page **pagep)
+{
+	int ret;
+	handle_t *handle;
+	struct page *page;
+	struct ext4_iloc iloc;
+
+	if (pos + len > ext4_get_max_inline_size(inode))
+		goto convert;
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		return ret;
+
+	/*
+	 * The possible write could happen in the inode,
+	 * so try to reserve the space in inode first.
+	 */
+	handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		handle = NULL;
+		goto out;
+	}
+
+	ret = ext4_prepare_inline_data(handle, inode, pos + len);
+	if (ret && ret != -ENOSPC)
+		goto out;
+
+	/* We don't have space in inline inode, so convert it to extent. */
+	if (ret == -ENOSPC) {
+		ext4_journal_stop(handle);
+		brelse(iloc.bh);
+		goto convert;
+	}
+
+	ret = ext4_journal_get_write_access(handle, iloc.bh);
+	if (ret)
+		goto out;
+
+	flags |= AOP_FLAG_NOFS;
+
+	page = grab_cache_page_write_begin(mapping, 0, flags);
+	if (!page) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	*pagep = page;
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		ret = 0;
+		unlock_page(page);
+		put_page(page);
+		goto out_up_read;
+	}
+
+	if (!PageUptodate(page)) {
+		ret = ext4_read_inline_page(inode, page);
+		if (ret < 0)
+			goto out_up_read;
+	}
+
+	ret = 1;
+	handle = NULL;
+out_up_read:
+	up_read(&EXT4_I(inode)->xattr_sem);
+out:
+	if (handle && (ret != 1))
+		ext4_journal_stop(handle);
+	brelse(iloc.bh);
+	return ret;
+convert:
+	return ext4_convert_inline_data_to_extent(mapping,
+						  inode, flags);
+}
+
+int ext4_write_inline_data_end(struct inode *inode, loff_t pos, unsigned len,
+			       unsigned copied, struct page *page)
+{
+	int ret, no_expand;
+	void *kaddr;
+	struct ext4_iloc iloc;
+
+	if (unlikely(copied < len)) {
+		if (!PageUptodate(page)) {
+			copied = 0;
+			goto out;
+		}
+	}
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret) {
+		ext4_std_error(inode->i_sb, ret);
+		copied = 0;
+		goto out;
+	}
+
+	ext4_write_lock_xattr(inode, &no_expand);
+	BUG_ON(!ext4_has_inline_data(inode));
+
+	kaddr = kmap_atomic(page);
+	ext4_write_inline_data(inode, &iloc, kaddr, pos, len);
+	kunmap_atomic(kaddr);
+	SetPageUptodate(page);
+	/* clear page dirty so that writepages wouldn't work for us. */
+	ClearPageDirty(page);
+
+	ext4_write_unlock_xattr(inode, &no_expand);
+	brelse(iloc.bh);
+	mark_inode_dirty(inode);
+out:
+	return copied;
+}
+
+struct buffer_head *
+ext4_journalled_write_inline_data(struct inode *inode,
+				  unsigned len,
+				  struct page *page)
+{
+	int ret, no_expand;
+	void *kaddr;
+	struct ext4_iloc iloc;
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret) {
+		ext4_std_error(inode->i_sb, ret);
+		return NULL;
+	}
+
+	ext4_write_lock_xattr(inode, &no_expand);
+	kaddr = kmap_atomic(page);
+	ext4_write_inline_data(inode, &iloc, kaddr, 0, len);
+	kunmap_atomic(kaddr);
+	ext4_write_unlock_xattr(inode, &no_expand);
+
+	return iloc.bh;
+}
+
+/*
+ * Try to make the page cache and handle ready for the inline data case.
+ * We can call this function in 2 cases:
+ * 1. The inode is created and the first write exceeds inline size. We can
+ *    clear the inode state safely.
+ * 2. The inode has inline data, then we need to read the data, make it
+ *    update and dirty so that ext4_da_writepages can handle it. We don't
+ *    need to start the journal since the file's metatdata isn't changed now.
+ */
+static int ext4_da_convert_inline_data_to_extent(struct address_space *mapping,
+						 struct inode *inode,
+						 unsigned flags,
+						 void **fsdata)
+{
+	int ret = 0, inline_size;
+	struct page *page;
+
+	page = grab_cache_page_write_begin(mapping, 0, flags);
+	if (!page)
+		return -ENOMEM;
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+		goto out;
+	}
+
+	inline_size = ext4_get_inline_size(inode);
+
+	if (!PageUptodate(page)) {
+		ret = ext4_read_inline_page(inode, page);
+		if (ret < 0)
+			goto out;
+	}
+
+	ret = __block_write_begin(page, 0, inline_size,
+				  ext4_da_get_block_prep);
+	if (ret) {
+		up_read(&EXT4_I(inode)->xattr_sem);
+		unlock_page(page);
+		put_page(page);
+		ext4_truncate_failed_write(inode);
+		return ret;
+	}
+
+	SetPageDirty(page);
+	SetPageUptodate(page);
+	ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+	*fsdata = (void *)CONVERT_INLINE_DATA;
+
+out:
+	up_read(&EXT4_I(inode)->xattr_sem);
+	if (page) {
+		unlock_page(page);
+		put_page(page);
+	}
+	return ret;
+}
+
+/*
+ * Prepare the write for the inline data.
+ * If the the data can be written into the inode, we just read
+ * the page and make it uptodate, and start the journal.
+ * Otherwise read the page, makes it dirty so that it can be
+ * handle in writepages(the i_disksize update is left to the
+ * normal ext4_da_write_end).
+ */
+int ext4_da_write_inline_data_begin(struct address_space *mapping,
+				    struct inode *inode,
+				    loff_t pos, unsigned len,
+				    unsigned flags,
+				    struct page **pagep,
+				    void **fsdata)
+{
+	int ret, inline_size;
+	handle_t *handle;
+	struct page *page;
+	struct ext4_iloc iloc;
+	int retries = 0;
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		return ret;
+
+retry_journal:
+	handle = ext4_journal_start(inode, EXT4_HT_INODE, 1);
+	if (IS_ERR(handle)) {
+		ret = PTR_ERR(handle);
+		goto out;
+	}
+
+	inline_size = ext4_get_max_inline_size(inode);
+
+	ret = -ENOSPC;
+	if (inline_size >= pos + len) {
+		ret = ext4_prepare_inline_data(handle, inode, pos + len);
+		if (ret && ret != -ENOSPC)
+			goto out_journal;
+	}
+
+	/*
+	 * We cannot recurse into the filesystem as the transaction
+	 * is already started.
+	 */
+	flags |= AOP_FLAG_NOFS;
+
+	if (ret == -ENOSPC) {
+		ext4_journal_stop(handle);
+		ret = ext4_da_convert_inline_data_to_extent(mapping,
+							    inode,
+							    flags,
+							    fsdata);
+		if (ret == -ENOSPC &&
+		    ext4_should_retry_alloc(inode->i_sb, &retries))
+			goto retry_journal;
+		goto out;
+	}
+
+	page = grab_cache_page_write_begin(mapping, 0, flags);
+	if (!page) {
+		ret = -ENOMEM;
+		goto out_journal;
+	}
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		ret = 0;
+		goto out_release_page;
+	}
+
+	if (!PageUptodate(page)) {
+		ret = ext4_read_inline_page(inode, page);
+		if (ret < 0)
+			goto out_release_page;
+	}
+	ret = ext4_journal_get_write_access(handle, iloc.bh);
+	if (ret)
+		goto out_release_page;
+
+	up_read(&EXT4_I(inode)->xattr_sem);
+	*pagep = page;
+	brelse(iloc.bh);
+	return 1;
+out_release_page:
+	up_read(&EXT4_I(inode)->xattr_sem);
+	unlock_page(page);
+	put_page(page);
+out_journal:
+	ext4_journal_stop(handle);
+out:
+	brelse(iloc.bh);
+	return ret;
+}
+
+int ext4_da_write_inline_data_end(struct inode *inode, loff_t pos,
+				  unsigned len, unsigned copied,
+				  struct page *page)
+{
+	int ret;
+
+	ret = ext4_write_inline_data_end(inode, pos, len, copied, page);
+	if (ret < 0) {
+		unlock_page(page);
+		put_page(page);
+		return ret;
+	}
+	copied = ret;
+
+	/*
+	 * No need to use i_size_read() here, the i_size
+	 * cannot change under us because we hold i_mutex.
+	 *
+	 * But it's important to update i_size while still holding page lock:
+	 * page writeout could otherwise come in and zero beyond i_size.
+	 */
+	if (pos+copied > inode->i_size)
+		i_size_write(inode, pos+copied);
+	unlock_page(page);
+	put_page(page);
+
+	/*
+	 * Don't mark the inode dirty under page lock. First, it unnecessarily
+	 * makes the holding time of page lock longer. Second, it forces lock
+	 * ordering of page lock and transaction start for journaling
+	 * filesystems.
+	 */
+	mark_inode_dirty(inode);
+
+	return copied;
+}
+
+#ifdef INLINE_DIR_DEBUG
+void ext4_show_inline_dir(struct inode *dir, struct buffer_head *bh,
+			  void *inline_start, int inline_size)
+{
+	int offset;
+	unsigned short de_len;
+	struct ext4_dir_entry_2 *de = inline_start;
+	void *dlimit = inline_start + inline_size;
+
+	trace_printk("inode %lu\n", dir->i_ino);
+	offset = 0;
+	while ((void *)de < dlimit) {
+		de_len = ext4_rec_len_from_disk(de->rec_len, inline_size);
+		trace_printk("de: off %u rlen %u name %.*s nlen %u ino %u\n",
+			     offset, de_len, de->name_len, de->name,
+			     de->name_len, le32_to_cpu(de->inode));
+		if (ext4_check_dir_entry(dir, NULL, de, bh,
+					 inline_start, inline_size, offset))
+			BUG();
+
+		offset += de_len;
+		de = (struct ext4_dir_entry_2 *) ((char *) de + de_len);
+	}
+}
+#else
+#define ext4_show_inline_dir(dir, bh, inline_start, inline_size)
+#endif
+
+/*
+ * Add a new entry into a inline dir.
+ * It will return -ENOSPC if no space is available, and -EIO
+ * and -EEXIST if directory entry already exists.
+ */
+static int ext4_add_dirent_to_inline(handle_t *handle,
+				     struct ext4_filename *fname,
+				     struct inode *dir,
+				     struct inode *inode,
+				     struct ext4_iloc *iloc,
+				     void *inline_start, int inline_size)
+{
+	int		err;
+	struct ext4_dir_entry_2 *de;
+
+	err = ext4_find_dest_de(dir, inode, iloc->bh, inline_start,
+				inline_size, fname, &de);
+	if (err)
+		return err;
+
+	BUFFER_TRACE(iloc->bh, "get_write_access");
+	err = ext4_journal_get_write_access(handle, iloc->bh);
+	if (err)
+		return err;
+	ext4_insert_dentry(inode, de, inline_size, fname);
+
+	ext4_show_inline_dir(dir, iloc->bh, inline_start, inline_size);
+
+	/*
+	 * XXX shouldn't update any times until successful
+	 * completion of syscall, but too many callers depend
+	 * on this.
+	 *
+	 * XXX similarly, too many callers depend on
+	 * ext4_new_inode() setting the times, but error
+	 * recovery deletes the inode, so the worst that can
+	 * happen is that the times are slightly out of date
+	 * and/or different from the directory change time.
+	 */
+	dir->i_mtime = dir->i_ctime = current_time(dir);
+	ext4_update_dx_flag(dir);
+	inode_inc_iversion(dir);
+	return 1;
+}
+
+static void *ext4_get_inline_xattr_pos(struct inode *inode,
+				       struct ext4_iloc *iloc)
+{
+	struct ext4_xattr_entry *entry;
+	struct ext4_xattr_ibody_header *header;
+
+	BUG_ON(!EXT4_I(inode)->i_inline_off);
+
+	header = IHDR(inode, ext4_raw_inode(iloc));
+	entry = (struct ext4_xattr_entry *)((void *)ext4_raw_inode(iloc) +
+					    EXT4_I(inode)->i_inline_off);
+
+	return (void *)IFIRST(header) + le16_to_cpu(entry->e_value_offs);
+}
+
+/* Set the final de to cover the whole block. */
+static void ext4_update_final_de(void *de_buf, int old_size, int new_size)
+{
+	struct ext4_dir_entry_2 *de, *prev_de;
+	void *limit;
+	int de_len;
+
+	de = (struct ext4_dir_entry_2 *)de_buf;
+	if (old_size) {
+		limit = de_buf + old_size;
+		do {
+			prev_de = de;
+			de_len = ext4_rec_len_from_disk(de->rec_len, old_size);
+			de_buf += de_len;
+			de = (struct ext4_dir_entry_2 *)de_buf;
+		} while (de_buf < limit);
+
+		prev_de->rec_len = ext4_rec_len_to_disk(de_len + new_size -
+							old_size, new_size);
+	} else {
+		/* this is just created, so create an empty entry. */
+		de->inode = 0;
+		de->rec_len = ext4_rec_len_to_disk(new_size, new_size);
+	}
+}
+
+static int ext4_update_inline_dir(handle_t *handle, struct inode *dir,
+				  struct ext4_iloc *iloc)
+{
+	int ret;
+	int old_size = EXT4_I(dir)->i_inline_size - EXT4_MIN_INLINE_DATA_SIZE;
+	int new_size = get_max_inline_xattr_value_size(dir, iloc);
+
+	if (new_size - old_size <= EXT4_DIR_REC_LEN(1))
+		return -ENOSPC;
+
+	ret = ext4_update_inline_data(handle, dir,
+				      new_size + EXT4_MIN_INLINE_DATA_SIZE);
+	if (ret)
+		return ret;
+
+	ext4_update_final_de(ext4_get_inline_xattr_pos(dir, iloc), old_size,
+			     EXT4_I(dir)->i_inline_size -
+						EXT4_MIN_INLINE_DATA_SIZE);
+	dir->i_size = EXT4_I(dir)->i_disksize = EXT4_I(dir)->i_inline_size;
+	return 0;
+}
+
+static void ext4_restore_inline_data(handle_t *handle, struct inode *inode,
+				     struct ext4_iloc *iloc,
+				     void *buf, int inline_size)
+{
+	ext4_create_inline_data(handle, inode, inline_size);
+	ext4_write_inline_data(inode, iloc, buf, 0, inline_size);
+	ext4_set_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+}
+
+static int ext4_finish_convert_inline_dir(handle_t *handle,
+					  struct inode *inode,
+					  struct buffer_head *dir_block,
+					  void *buf,
+					  int inline_size)
+{
+	int err, csum_size = 0, header_size = 0;
+	struct ext4_dir_entry_2 *de;
+	struct ext4_dir_entry_tail *t;
+	void *target = dir_block->b_data;
+
+	/*
+	 * First create "." and ".." and then copy the dir information
+	 * back to the block.
+	 */
+	de = (struct ext4_dir_entry_2 *)target;
+	de = ext4_init_dot_dotdot(inode, de,
+		inode->i_sb->s_blocksize, csum_size,
+		le32_to_cpu(((struct ext4_dir_entry_2 *)buf)->inode), 1);
+	header_size = (void *)de - target;
+
+	memcpy((void *)de, buf + EXT4_INLINE_DOTDOT_SIZE,
+		inline_size - EXT4_INLINE_DOTDOT_SIZE);
+
+	if (ext4_has_metadata_csum(inode->i_sb))
+		csum_size = sizeof(struct ext4_dir_entry_tail);
+
+	inode->i_size = inode->i_sb->s_blocksize;
+	i_size_write(inode, inode->i_sb->s_blocksize);
+	EXT4_I(inode)->i_disksize = inode->i_sb->s_blocksize;
+	ext4_update_final_de(dir_block->b_data,
+			inline_size - EXT4_INLINE_DOTDOT_SIZE + header_size,
+			inode->i_sb->s_blocksize - csum_size);
+
+	if (csum_size) {
+		t = EXT4_DIRENT_TAIL(dir_block->b_data,
+				     inode->i_sb->s_blocksize);
+		initialize_dirent_tail(t, inode->i_sb->s_blocksize);
+	}
+	set_buffer_uptodate(dir_block);
+	err = ext4_handle_dirty_dirent_node(handle, inode, dir_block);
+	if (err)
+		return err;
+	set_buffer_verified(dir_block);
+	return ext4_mark_inode_dirty(handle, inode);
+}
+
+static int ext4_convert_inline_data_nolock(handle_t *handle,
+					   struct inode *inode,
+					   struct ext4_iloc *iloc)
+{
+	int error;
+	void *buf = NULL;
+	struct buffer_head *data_bh = NULL;
+	struct ext4_map_blocks map;
+	int inline_size;
+
+	inline_size = ext4_get_inline_size(inode);
+	buf = kmalloc(inline_size, GFP_NOFS);
+	if (!buf) {
+		error = -ENOMEM;
+		goto out;
+	}
+
+	error = ext4_read_inline_data(inode, buf, inline_size, iloc);
+	if (error < 0)
+		goto out;
+
+	/*
+	 * Make sure the inline directory entries pass checks before we try to
+	 * convert them, so that we avoid touching stuff that needs fsck.
+	 */
+	if (S_ISDIR(inode->i_mode)) {
+		error = ext4_check_all_de(inode, iloc->bh,
+					buf + EXT4_INLINE_DOTDOT_SIZE,
+					inline_size - EXT4_INLINE_DOTDOT_SIZE);
+		if (error)
+			goto out;
+	}
+
+	error = ext4_destroy_inline_data_nolock(handle, inode);
+	if (error)
+		goto out;
+
+	map.m_lblk = 0;
+	map.m_len = 1;
+	map.m_flags = 0;
+	error = ext4_map_blocks(handle, inode, &map, EXT4_GET_BLOCKS_CREATE);
+	if (error < 0)
+		goto out_restore;
+	if (!(map.m_flags & EXT4_MAP_MAPPED)) {
+		error = -EIO;
+		goto out_restore;
+	}
+
+	data_bh = sb_getblk(inode->i_sb, map.m_pblk);
+	if (!data_bh) {
+		error = -ENOMEM;
+		goto out_restore;
+	}
+
+	lock_buffer(data_bh);
+	error = ext4_journal_get_create_access(handle, data_bh);
+	if (error) {
+		unlock_buffer(data_bh);
+		error = -EIO;
+		goto out_restore;
+	}
+	memset(data_bh->b_data, 0, inode->i_sb->s_blocksize);
+
+	if (!S_ISDIR(inode->i_mode)) {
+		memcpy(data_bh->b_data, buf, inline_size);
+		set_buffer_uptodate(data_bh);
+		error = ext4_handle_dirty_metadata(handle,
+						   inode, data_bh);
+	} else {
+		error = ext4_finish_convert_inline_dir(handle, inode, data_bh,
+						       buf, inline_size);
+	}
+
+	unlock_buffer(data_bh);
+out_restore:
+	if (error)
+		ext4_restore_inline_data(handle, inode, iloc, buf, inline_size);
+
+out:
+	brelse(data_bh);
+	kfree(buf);
+	return error;
+}
+
+/*
+ * Try to add the new entry to the inline data.
+ * If succeeds, return 0. If not, extended the inline dir and copied data to
+ * the new created block.
+ */
+int ext4_try_add_inline_entry(handle_t *handle, struct ext4_filename *fname,
+			      struct inode *dir, struct inode *inode)
+{
+	int ret, inline_size, no_expand;
+	void *inline_start;
+	struct ext4_iloc iloc;
+
+	ret = ext4_get_inode_loc(dir, &iloc);
+	if (ret)
+		return ret;
+
+	ext4_write_lock_xattr(dir, &no_expand);
+	if (!ext4_has_inline_data(dir))
+		goto out;
+
+	inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
+						 EXT4_INLINE_DOTDOT_SIZE;
+	inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
+
+	ret = ext4_add_dirent_to_inline(handle, fname, dir, inode, &iloc,
+					inline_start, inline_size);
+	if (ret != -ENOSPC)
+		goto out;
+
+	/* check whether it can be inserted to inline xattr space. */
+	inline_size = EXT4_I(dir)->i_inline_size -
+			EXT4_MIN_INLINE_DATA_SIZE;
+	if (!inline_size) {
+		/* Try to use the xattr space.*/
+		ret = ext4_update_inline_dir(handle, dir, &iloc);
+		if (ret && ret != -ENOSPC)
+			goto out;
+
+		inline_size = EXT4_I(dir)->i_inline_size -
+				EXT4_MIN_INLINE_DATA_SIZE;
+	}
+
+	if (inline_size) {
+		inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
+
+		ret = ext4_add_dirent_to_inline(handle, fname, dir,
+						inode, &iloc, inline_start,
+						inline_size);
+
+		if (ret != -ENOSPC)
+			goto out;
+	}
+
+	/*
+	 * The inline space is filled up, so create a new block for it.
+	 * As the extent tree will be created, we have to save the inline
+	 * dir first.
+	 */
+	ret = ext4_convert_inline_data_nolock(handle, dir, &iloc);
+
+out:
+	ext4_write_unlock_xattr(dir, &no_expand);
+	ext4_mark_inode_dirty(handle, dir);
+	brelse(iloc.bh);
+	return ret;
+}
+
+/*
+ * This function fills a red-black tree with information from an
+ * inlined dir.  It returns the number directory entries loaded
+ * into the tree.  If there is an error it is returned in err.
+ */
+int htree_inlinedir_to_tree(struct file *dir_file,
+			    struct inode *dir, ext4_lblk_t block,
+			    struct dx_hash_info *hinfo,
+			    __u32 start_hash, __u32 start_minor_hash,
+			    int *has_inline_data)
+{
+	int err = 0, count = 0;
+	unsigned int parent_ino;
+	int pos;
+	struct ext4_dir_entry_2 *de;
+	struct inode *inode = file_inode(dir_file);
+	int ret, inline_size = 0;
+	struct ext4_iloc iloc;
+	void *dir_buf = NULL;
+	struct ext4_dir_entry_2 fake;
+	struct fscrypt_str tmp_str;
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		return ret;
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		up_read(&EXT4_I(inode)->xattr_sem);
+		*has_inline_data = 0;
+		goto out;
+	}
+
+	inline_size = ext4_get_inline_size(inode);
+	dir_buf = kmalloc(inline_size, GFP_NOFS);
+	if (!dir_buf) {
+		ret = -ENOMEM;
+		up_read(&EXT4_I(inode)->xattr_sem);
+		goto out;
+	}
+
+	ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
+	up_read(&EXT4_I(inode)->xattr_sem);
+	if (ret < 0)
+		goto out;
+
+	pos = 0;
+	parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
+	while (pos < inline_size) {
+		/*
+		 * As inlined dir doesn't store any information about '.' and
+		 * only the inode number of '..' is stored, we have to handle
+		 * them differently.
+		 */
+		if (pos == 0) {
+			fake.inode = cpu_to_le32(inode->i_ino);
+			fake.name_len = 1;
+			strcpy(fake.name, ".");
+			fake.rec_len = ext4_rec_len_to_disk(
+						EXT4_DIR_REC_LEN(fake.name_len),
+						inline_size);
+			ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
+			de = &fake;
+			pos = EXT4_INLINE_DOTDOT_OFFSET;
+		} else if (pos == EXT4_INLINE_DOTDOT_OFFSET) {
+			fake.inode = cpu_to_le32(parent_ino);
+			fake.name_len = 2;
+			strcpy(fake.name, "..");
+			fake.rec_len = ext4_rec_len_to_disk(
+						EXT4_DIR_REC_LEN(fake.name_len),
+						inline_size);
+			ext4_set_de_type(inode->i_sb, &fake, S_IFDIR);
+			de = &fake;
+			pos = EXT4_INLINE_DOTDOT_SIZE;
+		} else {
+			de = (struct ext4_dir_entry_2 *)(dir_buf + pos);
+			pos += ext4_rec_len_from_disk(de->rec_len, inline_size);
+			if (ext4_check_dir_entry(inode, dir_file, de,
+					 iloc.bh, dir_buf,
+					 inline_size, pos)) {
+				ret = count;
+				goto out;
+			}
+		}
+
+		ext4fs_dirhash(de->name, de->name_len, hinfo);
+		if ((hinfo->hash < start_hash) ||
+		    ((hinfo->hash == start_hash) &&
+		     (hinfo->minor_hash < start_minor_hash)))
+			continue;
+		if (de->inode == 0)
+			continue;
+		tmp_str.name = de->name;
+		tmp_str.len = de->name_len;
+		err = ext4_htree_store_dirent(dir_file, hinfo->hash,
+					      hinfo->minor_hash, de, &tmp_str);
+		if (err) {
+			count = err;
+			goto out;
+		}
+		count++;
+	}
+	ret = count;
+out:
+	kfree(dir_buf);
+	brelse(iloc.bh);
+	return ret;
+}
+
+/*
+ * So this function is called when the volume is mkfsed with
+ * dir_index disabled. In order to keep f_pos persistent
+ * after we convert from an inlined dir to a blocked based,
+ * we just pretend that we are a normal dir and return the
+ * offset as if '.' and '..' really take place.
+ *
+ */
+int ext4_read_inline_dir(struct file *file,
+			 struct dir_context *ctx,
+			 int *has_inline_data)
+{
+	unsigned int offset, parent_ino;
+	int i;
+	struct ext4_dir_entry_2 *de;
+	struct super_block *sb;
+	struct inode *inode = file_inode(file);
+	int ret, inline_size = 0;
+	struct ext4_iloc iloc;
+	void *dir_buf = NULL;
+	int dotdot_offset, dotdot_size, extra_offset, extra_size;
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		return ret;
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		up_read(&EXT4_I(inode)->xattr_sem);
+		*has_inline_data = 0;
+		goto out;
+	}
+
+	inline_size = ext4_get_inline_size(inode);
+	dir_buf = kmalloc(inline_size, GFP_NOFS);
+	if (!dir_buf) {
+		ret = -ENOMEM;
+		up_read(&EXT4_I(inode)->xattr_sem);
+		goto out;
+	}
+
+	ret = ext4_read_inline_data(inode, dir_buf, inline_size, &iloc);
+	up_read(&EXT4_I(inode)->xattr_sem);
+	if (ret < 0)
+		goto out;
+
+	ret = 0;
+	sb = inode->i_sb;
+	parent_ino = le32_to_cpu(((struct ext4_dir_entry_2 *)dir_buf)->inode);
+	offset = ctx->pos;
+
+	/*
+	 * dotdot_offset and dotdot_size is the real offset and
+	 * size for ".." and "." if the dir is block based while
+	 * the real size for them are only EXT4_INLINE_DOTDOT_SIZE.
+	 * So we will use extra_offset and extra_size to indicate them
+	 * during the inline dir iteration.
+	 */
+	dotdot_offset = EXT4_DIR_REC_LEN(1);
+	dotdot_size = dotdot_offset + EXT4_DIR_REC_LEN(2);
+	extra_offset = dotdot_size - EXT4_INLINE_DOTDOT_SIZE;
+	extra_size = extra_offset + inline_size;
+
+	/*
+	 * If the version has changed since the last call to
+	 * readdir(2), then we might be pointing to an invalid
+	 * dirent right now.  Scan from the start of the inline
+	 * dir to make sure.
+	 */
+	if (!inode_eq_iversion(inode, file->f_version)) {
+		for (i = 0; i < extra_size && i < offset;) {
+			/*
+			 * "." is with offset 0 and
+			 * ".." is dotdot_offset.
+			 */
+			if (!i) {
+				i = dotdot_offset;
+				continue;
+			} else if (i == dotdot_offset) {
+				i = dotdot_size;
+				continue;
+			}
+			/* for other entry, the real offset in
+			 * the buf has to be tuned accordingly.
+			 */
+			de = (struct ext4_dir_entry_2 *)
+				(dir_buf + i - extra_offset);
+			/* It's too expensive to do a full
+			 * dirent test each time round this
+			 * loop, but we do have to test at
+			 * least that it is non-zero.  A
+			 * failure will be detected in the
+			 * dirent test below. */
+			if (ext4_rec_len_from_disk(de->rec_len, extra_size)
+				< EXT4_DIR_REC_LEN(1))
+				break;
+			i += ext4_rec_len_from_disk(de->rec_len,
+						    extra_size);
+		}
+		offset = i;
+		ctx->pos = offset;
+		file->f_version = inode_query_iversion(inode);
+	}
+
+	while (ctx->pos < extra_size) {
+		if (ctx->pos == 0) {
+			if (!dir_emit(ctx, ".", 1, inode->i_ino, DT_DIR))
+				goto out;
+			ctx->pos = dotdot_offset;
+			continue;
+		}
+
+		if (ctx->pos == dotdot_offset) {
+			if (!dir_emit(ctx, "..", 2, parent_ino, DT_DIR))
+				goto out;
+			ctx->pos = dotdot_size;
+			continue;
+		}
+
+		de = (struct ext4_dir_entry_2 *)
+			(dir_buf + ctx->pos - extra_offset);
+		if (ext4_check_dir_entry(inode, file, de, iloc.bh, dir_buf,
+					 extra_size, ctx->pos))
+			goto out;
+		if (le32_to_cpu(de->inode)) {
+			if (!dir_emit(ctx, de->name, de->name_len,
+				      le32_to_cpu(de->inode),
+				      get_dtype(sb, de->file_type)))
+				goto out;
+		}
+		ctx->pos += ext4_rec_len_from_disk(de->rec_len, extra_size);
+	}
+out:
+	kfree(dir_buf);
+	brelse(iloc.bh);
+	return ret;
+}
+
+struct buffer_head *ext4_get_first_inline_block(struct inode *inode,
+					struct ext4_dir_entry_2 **parent_de,
+					int *retval)
+{
+	struct ext4_iloc iloc;
+
+	*retval = ext4_get_inode_loc(inode, &iloc);
+	if (*retval)
+		return NULL;
+
+	*parent_de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
+
+	return iloc.bh;
+}
+
+/*
+ * Try to create the inline data for the new dir.
+ * If it succeeds, return 0, otherwise return the error.
+ * In case of ENOSPC, the caller should create the normal disk layout dir.
+ */
+int ext4_try_create_inline_dir(handle_t *handle, struct inode *parent,
+			       struct inode *inode)
+{
+	int ret, inline_size = EXT4_MIN_INLINE_DATA_SIZE;
+	struct ext4_iloc iloc;
+	struct ext4_dir_entry_2 *de;
+
+	ret = ext4_get_inode_loc(inode, &iloc);
+	if (ret)
+		return ret;
+
+	ret = ext4_prepare_inline_data(handle, inode, inline_size);
+	if (ret)
+		goto out;
+
+	/*
+	 * For inline dir, we only save the inode information for the ".."
+	 * and create a fake dentry to cover the left space.
+	 */
+	de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
+	de->inode = cpu_to_le32(parent->i_ino);
+	de = (struct ext4_dir_entry_2 *)((void *)de + EXT4_INLINE_DOTDOT_SIZE);
+	de->inode = 0;
+	de->rec_len = ext4_rec_len_to_disk(
+				inline_size - EXT4_INLINE_DOTDOT_SIZE,
+				inline_size);
+	set_nlink(inode, 2);
+	inode->i_size = EXT4_I(inode)->i_disksize = inline_size;
+out:
+	brelse(iloc.bh);
+	return ret;
+}
+
+struct buffer_head *ext4_find_inline_entry(struct inode *dir,
+					struct ext4_filename *fname,
+					struct ext4_dir_entry_2 **res_dir,
+					int *has_inline_data)
+{
+	int ret;
+	struct ext4_iloc iloc;
+	void *inline_start;
+	int inline_size;
+
+	if (ext4_get_inode_loc(dir, &iloc))
+		return NULL;
+
+	down_read(&EXT4_I(dir)->xattr_sem);
+	if (!ext4_has_inline_data(dir)) {
+		*has_inline_data = 0;
+		goto out;
+	}
+
+	inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
+						EXT4_INLINE_DOTDOT_SIZE;
+	inline_size = EXT4_MIN_INLINE_DATA_SIZE - EXT4_INLINE_DOTDOT_SIZE;
+	ret = ext4_search_dir(iloc.bh, inline_start, inline_size,
+			      dir, fname, 0, res_dir);
+	if (ret == 1)
+		goto out_find;
+	if (ret < 0)
+		goto out;
+
+	if (ext4_get_inline_size(dir) == EXT4_MIN_INLINE_DATA_SIZE)
+		goto out;
+
+	inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
+	inline_size = ext4_get_inline_size(dir) - EXT4_MIN_INLINE_DATA_SIZE;
+
+	ret = ext4_search_dir(iloc.bh, inline_start, inline_size,
+			      dir, fname, 0, res_dir);
+	if (ret == 1)
+		goto out_find;
+
+out:
+	brelse(iloc.bh);
+	iloc.bh = NULL;
+out_find:
+	up_read(&EXT4_I(dir)->xattr_sem);
+	return iloc.bh;
+}
+
+int ext4_delete_inline_entry(handle_t *handle,
+			     struct inode *dir,
+			     struct ext4_dir_entry_2 *de_del,
+			     struct buffer_head *bh,
+			     int *has_inline_data)
+{
+	int err, inline_size, no_expand;
+	struct ext4_iloc iloc;
+	void *inline_start;
+
+	err = ext4_get_inode_loc(dir, &iloc);
+	if (err)
+		return err;
+
+	ext4_write_lock_xattr(dir, &no_expand);
+	if (!ext4_has_inline_data(dir)) {
+		*has_inline_data = 0;
+		goto out;
+	}
+
+	if ((void *)de_del - ((void *)ext4_raw_inode(&iloc)->i_block) <
+		EXT4_MIN_INLINE_DATA_SIZE) {
+		inline_start = (void *)ext4_raw_inode(&iloc)->i_block +
+					EXT4_INLINE_DOTDOT_SIZE;
+		inline_size = EXT4_MIN_INLINE_DATA_SIZE -
+				EXT4_INLINE_DOTDOT_SIZE;
+	} else {
+		inline_start = ext4_get_inline_xattr_pos(dir, &iloc);
+		inline_size = ext4_get_inline_size(dir) -
+				EXT4_MIN_INLINE_DATA_SIZE;
+	}
+
+	BUFFER_TRACE(bh, "get_write_access");
+	err = ext4_journal_get_write_access(handle, bh);
+	if (err)
+		goto out;
+
+	err = ext4_generic_delete_entry(handle, dir, de_del, bh,
+					inline_start, inline_size, 0);
+	if (err)
+		goto out;
+
+	ext4_show_inline_dir(dir, iloc.bh, inline_start, inline_size);
+out:
+	ext4_write_unlock_xattr(dir, &no_expand);
+	if (likely(err == 0))
+		err = ext4_mark_inode_dirty(handle, dir);
+	brelse(iloc.bh);
+	if (err != -ENOENT)
+		ext4_std_error(dir->i_sb, err);
+	return err;
+}
+
+/*
+ * Get the inline dentry at offset.
+ */
+static inline struct ext4_dir_entry_2 *
+ext4_get_inline_entry(struct inode *inode,
+		      struct ext4_iloc *iloc,
+		      unsigned int offset,
+		      void **inline_start,
+		      int *inline_size)
+{
+	void *inline_pos;
+
+	BUG_ON(offset > ext4_get_inline_size(inode));
+
+	if (offset < EXT4_MIN_INLINE_DATA_SIZE) {
+		inline_pos = (void *)ext4_raw_inode(iloc)->i_block;
+		*inline_size = EXT4_MIN_INLINE_DATA_SIZE;
+	} else {
+		inline_pos = ext4_get_inline_xattr_pos(inode, iloc);
+		offset -= EXT4_MIN_INLINE_DATA_SIZE;
+		*inline_size = ext4_get_inline_size(inode) -
+				EXT4_MIN_INLINE_DATA_SIZE;
+	}
+
+	if (inline_start)
+		*inline_start = inline_pos;
+	return (struct ext4_dir_entry_2 *)(inline_pos + offset);
+}
+
+bool empty_inline_dir(struct inode *dir, int *has_inline_data)
+{
+	int err, inline_size;
+	struct ext4_iloc iloc;
+	size_t inline_len;
+	void *inline_pos;
+	unsigned int offset;
+	struct ext4_dir_entry_2 *de;
+	bool ret = true;
+
+	err = ext4_get_inode_loc(dir, &iloc);
+	if (err) {
+		EXT4_ERROR_INODE(dir, "error %d getting inode %lu block",
+				 err, dir->i_ino);
+		return true;
+	}
+
+	down_read(&EXT4_I(dir)->xattr_sem);
+	if (!ext4_has_inline_data(dir)) {
+		*has_inline_data = 0;
+		goto out;
+	}
+
+	de = (struct ext4_dir_entry_2 *)ext4_raw_inode(&iloc)->i_block;
+	if (!le32_to_cpu(de->inode)) {
+		ext4_warning(dir->i_sb,
+			     "bad inline directory (dir #%lu) - no `..'",
+			     dir->i_ino);
+		ret = true;
+		goto out;
+	}
+
+	inline_len = ext4_get_inline_size(dir);
+	offset = EXT4_INLINE_DOTDOT_SIZE;
+	while (offset < inline_len) {
+		de = ext4_get_inline_entry(dir, &iloc, offset,
+					   &inline_pos, &inline_size);
+		if (ext4_check_dir_entry(dir, NULL, de,
+					 iloc.bh, inline_pos,
+					 inline_size, offset)) {
+			ext4_warning(dir->i_sb,
+				     "bad inline directory (dir #%lu) - "
+				     "inode %u, rec_len %u, name_len %d"
+				     "inline size %d",
+				     dir->i_ino, le32_to_cpu(de->inode),
+				     le16_to_cpu(de->rec_len), de->name_len,
+				     inline_size);
+			ret = true;
+			goto out;
+		}
+		if (le32_to_cpu(de->inode)) {
+			ret = false;
+			goto out;
+		}
+		offset += ext4_rec_len_from_disk(de->rec_len, inline_size);
+	}
+
+out:
+	up_read(&EXT4_I(dir)->xattr_sem);
+	brelse(iloc.bh);
+	return ret;
+}
+
+int ext4_destroy_inline_data(handle_t *handle, struct inode *inode)
+{
+	int ret, no_expand;
+
+	ext4_write_lock_xattr(inode, &no_expand);
+	ret = ext4_destroy_inline_data_nolock(handle, inode);
+	ext4_write_unlock_xattr(inode, &no_expand);
+
+	return ret;
+}
+
+int ext4_inline_data_iomap(struct inode *inode, struct iomap *iomap)
+{
+	__u64 addr;
+	int error = -EAGAIN;
+	struct ext4_iloc iloc;
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode))
+		goto out;
+
+	error = ext4_get_inode_loc(inode, &iloc);
+	if (error)
+		goto out;
+
+	addr = (__u64)iloc.bh->b_blocknr << inode->i_sb->s_blocksize_bits;
+	addr += (char *)ext4_raw_inode(&iloc) - iloc.bh->b_data;
+	addr += offsetof(struct ext4_inode, i_block);
+
+	brelse(iloc.bh);
+
+	iomap->addr = addr;
+	iomap->offset = 0;
+	iomap->length = min_t(loff_t, ext4_get_inline_size(inode),
+			      i_size_read(inode));
+	iomap->type = IOMAP_INLINE;
+	iomap->flags = 0;
+
+out:
+	up_read(&EXT4_I(inode)->xattr_sem);
+	return error;
+}
+
+int ext4_inline_data_fiemap(struct inode *inode,
+			    struct fiemap_extent_info *fieinfo,
+			    int *has_inline, __u64 start, __u64 len)
+{
+	__u64 physical = 0;
+	__u64 inline_len;
+	__u32 flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED |
+		FIEMAP_EXTENT_LAST;
+	int error = 0;
+	struct ext4_iloc iloc;
+
+	down_read(&EXT4_I(inode)->xattr_sem);
+	if (!ext4_has_inline_data(inode)) {
+		*has_inline = 0;
+		goto out;
+	}
+	inline_len = min_t(size_t, ext4_get_inline_size(inode),
+			   i_size_read(inode));
+	if (start >= inline_len)
+		goto out;
+	if (start + len < inline_len)
+		inline_len = start + len;
+	inline_len -= start;
+
+	error = ext4_get_inode_loc(inode, &iloc);
+	if (error)
+		goto out;
+
+	physical = (__u64)iloc.bh->b_blocknr << inode->i_sb->s_blocksize_bits;
+	physical += (char *)ext4_raw_inode(&iloc) - iloc.bh->b_data;
+	physical += offsetof(struct ext4_inode, i_block);
+
+	if (physical)
+		error = fiemap_fill_next_extent(fieinfo, start, physical,
+						inline_len, flags);
+	brelse(iloc.bh);
+out:
+	up_read(&EXT4_I(inode)->xattr_sem);
+	return (error < 0 ? error : 0);
+}
+
+int ext4_inline_data_truncate(struct inode *inode, int *has_inline)
+{
+	handle_t *handle;
+	int inline_size, value_len, needed_blocks, no_expand, err = 0;
+	size_t i_size;
+	void *value = NULL;
+	struct ext4_xattr_ibody_find is = {
+		.s = { .not_found = -ENODATA, },
+	};
+	struct ext4_xattr_info i = {
+		.name_index = EXT4_XATTR_INDEX_SYSTEM,
+		.name = EXT4_XATTR_SYSTEM_DATA,
+	};
+
+
+	needed_blocks = ext4_writepage_trans_blocks(inode);
+	handle = ext4_journal_start(inode, EXT4_HT_INODE, needed_blocks);
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+
+	ext4_write_lock_xattr(inode, &no_expand);
+	if (!ext4_has_inline_data(inode)) {
+		*has_inline = 0;
+		ext4_journal_stop(handle);
+		return 0;
+	}
+
+	if ((err = ext4_orphan_add(handle, inode)) != 0)
+		goto out;
+
+	if ((err = ext4_get_inode_loc(inode, &is.iloc)) != 0)
+		goto out;
+
+	down_write(&EXT4_I(inode)->i_data_sem);
+	i_size = inode->i_size;
+	inline_size = ext4_get_inline_size(inode);
+	EXT4_I(inode)->i_disksize = i_size;
+
+	if (i_size < inline_size) {
+		/* Clear the content in the xattr space. */
+		if (inline_size > EXT4_MIN_INLINE_DATA_SIZE) {
+			if ((err = ext4_xattr_ibody_find(inode, &i, &is)) != 0)
+				goto out_error;
+
+			BUG_ON(is.s.not_found);
+
+			value_len = le32_to_cpu(is.s.here->e_value_size);
+			value = kmalloc(value_len, GFP_NOFS);
+			if (!value) {
+				err = -ENOMEM;
+				goto out_error;
+			}
+
+			err = ext4_xattr_ibody_get(inode, i.name_index,
+						   i.name, value, value_len);
+			if (err <= 0)
+				goto out_error;
+
+			i.value = value;
+			i.value_len = i_size > EXT4_MIN_INLINE_DATA_SIZE ?
+					i_size - EXT4_MIN_INLINE_DATA_SIZE : 0;
+			err = ext4_xattr_ibody_inline_set(handle, inode,
+							  &i, &is);
+			if (err)
+				goto out_error;
+		}
+
+		/* Clear the content within i_blocks. */
+		if (i_size < EXT4_MIN_INLINE_DATA_SIZE) {
+			void *p = (void *) ext4_raw_inode(&is.iloc)->i_block;
+			memset(p + i_size, 0,
+			       EXT4_MIN_INLINE_DATA_SIZE - i_size);
+		}
+
+		EXT4_I(inode)->i_inline_size = i_size <
+					EXT4_MIN_INLINE_DATA_SIZE ?
+					EXT4_MIN_INLINE_DATA_SIZE : i_size;
+	}
+
+out_error:
+	up_write(&EXT4_I(inode)->i_data_sem);
+out:
+	brelse(is.iloc.bh);
+	ext4_write_unlock_xattr(inode, &no_expand);
+	kfree(value);
+	if (inode->i_nlink)
+		ext4_orphan_del(handle, inode);
+
+	if (err == 0) {
+		inode->i_mtime = inode->i_ctime = current_time(inode);
+		err = ext4_mark_inode_dirty(handle, inode);
+		if (IS_SYNC(inode))
+			ext4_handle_sync(handle);
+	}
+	ext4_journal_stop(handle);
+	return err;
+}
+
+int ext4_convert_inline_data(struct inode *inode)
+{
+	int error, needed_blocks, no_expand;
+	handle_t *handle;
+	struct ext4_iloc iloc;
+
+	if (!ext4_has_inline_data(inode)) {
+		ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA);
+		return 0;
+	}
+
+	needed_blocks = ext4_writepage_trans_blocks(inode);
+
+	iloc.bh = NULL;
+	error = ext4_get_inode_loc(inode, &iloc);
+	if (error)
+		return error;
+
+	handle = ext4_journal_start(inode, EXT4_HT_WRITE_PAGE, needed_blocks);
+	if (IS_ERR(handle)) {
+		error = PTR_ERR(handle);
+		goto out_free;
+	}
+
+	ext4_write_lock_xattr(inode, &no_expand);
+	if (ext4_has_inline_data(inode))
+		error = ext4_convert_inline_data_nolock(handle, inode, &iloc);
+	ext4_write_unlock_xattr(inode, &no_expand);
+	ext4_journal_stop(handle);
+out_free:
+	brelse(iloc.bh);
+	return error;
+}