diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index cfc4e01..0f44577 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1265,6 +1265,9 @@ struct ext4_sb_info {
 	/* locality groups */
 	struct ext4_locality_group __percpu *s_locality_groups;
 
+	/* the length of zero-out chunk */
+	unsigned int s_extent_zeroout_len;
+
 	/* for write statistics */
 	unsigned long s_sectors_written_start;
 	u64 s_kbytes_written;
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 91341ec..e921c02 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -3029,7 +3029,6 @@ out:
 	return err ? err : map->m_len;
 }
 
-#define EXT4_EXT_ZERO_LEN 7
 /*
  * This function is called by ext4_ext_map_blocks() if someone tries to write
  * to an uninitialized extent. It may result in splitting the uninitialized
@@ -3055,6 +3054,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 					   struct ext4_map_blocks *map,
 					   struct ext4_ext_path *path)
 {
+	struct ext4_sb_info *sbi;
 	struct ext4_extent_header *eh;
 	struct ext4_map_blocks split_map;
 	struct ext4_extent zero_ex;
@@ -3069,6 +3069,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 		"block %llu, max_blocks %u\n", inode->i_ino,
 		(unsigned long long)map->m_lblk, map->m_len);
 
+	sbi = EXT4_SB(inode->i_sb);
 	eof_block = (inode->i_size + inode->i_sb->s_blocksize - 1) >>
 		inode->i_sb->s_blocksize_bits;
 	if (eof_block < map->m_lblk + map->m_len)
@@ -3168,8 +3169,8 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 	 */
 	split_flag |= ee_block + ee_len <= eof_block ? EXT4_EXT_MAY_ZEROOUT : 0;
 
-	/* If extent has less than 2*EXT4_EXT_ZERO_LEN zerout directly */
-	if (ee_len <= 2*EXT4_EXT_ZERO_LEN &&
+	/* If extent has less than 2*s_extent_zeroout_len zerout directly */
+	if (ee_len <= 2*sbi->s_extent_zeroout_len &&
 	    (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
 		err = ext4_ext_zeroout(inode, ex);
 		if (err)
@@ -3195,7 +3196,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 	split_map.m_len = map->m_len;
 
 	if (allocated > map->m_len) {
-		if (allocated <= EXT4_EXT_ZERO_LEN &&
+		if (allocated <= sbi->s_extent_zeroout_len &&
 		    (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
 			/* case 3 */
 			zero_ex.ee_block =
@@ -3209,7 +3210,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 			split_map.m_lblk = map->m_lblk;
 			split_map.m_len = allocated;
 		} else if ((map->m_lblk - ee_block + map->m_len <
-			   EXT4_EXT_ZERO_LEN) &&
+			   sbi->s_extent_zeroout_len) &&
 			   (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
 			/* case 2 */
 			if (map->m_lblk != ee_block) {
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index eb7aa3e..ad6cf73 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -2535,6 +2535,7 @@ EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
+EXT4_RW_ATTR_SBI_UI(extent_zeroout_len, s_extent_zeroout_len);
 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
 
 static struct attribute *ext4_attrs[] = {
@@ -2550,6 +2551,7 @@ static struct attribute *ext4_attrs[] = {
 	ATTR_LIST(mb_stream_req),
 	ATTR_LIST(mb_group_prealloc),
 	ATTR_LIST(max_writeback_mb_bump),
+	ATTR_LIST(extent_zeroout_len),
 	ATTR_LIST(trigger_fs_error),
 	NULL,
 };
@@ -3626,6 +3628,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 
 	sbi->s_stripe = ext4_get_stripe_size(sbi);
 	sbi->s_max_writeback_mb_bump = 128;
+	sbi->s_extent_zeroout_len = 256;
 
 	/*
 	 * set up enough so that it can read an inode