diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 9334f55dab6f..eb37d76bf911 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -158,7 +158,6 @@ struct ext4_allocation_request {
 #define EXT4_MAP_MAPPED		(1 << BH_Mapped)
 #define EXT4_MAP_UNWRITTEN	(1 << BH_Unwritten)
 #define EXT4_MAP_BOUNDARY	(1 << BH_Boundary)
-#define EXT4_MAP_UNINIT		(1 << BH_Uninit)
 /* Sometimes (in the bigalloc case, from ext4_da_get_block_prep) the caller of
  * ext4_map_blocks wants to know whether or not the underlying cluster has
  * already been accounted for. EXT4_MAP_FROM_CLUSTER conveys to the caller that
@@ -169,7 +168,7 @@ struct ext4_allocation_request {
 #define EXT4_MAP_FROM_CLUSTER	(1 << BH_AllocFromCluster)
 #define EXT4_MAP_FLAGS		(EXT4_MAP_NEW | EXT4_MAP_MAPPED |\
 				 EXT4_MAP_UNWRITTEN | EXT4_MAP_BOUNDARY |\
-				 EXT4_MAP_UNINIT | EXT4_MAP_FROM_CLUSTER)
+				 EXT4_MAP_FROM_CLUSTER)
 
 struct ext4_map_blocks {
 	ext4_fsblk_t m_pblk;
@@ -184,7 +183,7 @@ struct ext4_map_blocks {
 #define	EXT4_IO_END_UNWRITTEN	0x0001
 
 /*
- * For converting uninitialized extents on a work queue. 'handle' is used for
+ * For converting unwritten extents on a work queue. 'handle' is used for
  * buffered writeback.
  */
 typedef struct ext4_io_end {
@@ -537,26 +536,26 @@ enum {
 /*
  * Flags used by ext4_map_blocks()
  */
-	/* Allocate any needed blocks and/or convert an unitialized
+	/* Allocate any needed blocks and/or convert an unwritten
 	   extent to be an initialized ext4 */
 #define EXT4_GET_BLOCKS_CREATE			0x0001
-	/* Request the creation of an unitialized extent */
-#define EXT4_GET_BLOCKS_UNINIT_EXT		0x0002
-#define EXT4_GET_BLOCKS_CREATE_UNINIT_EXT	(EXT4_GET_BLOCKS_UNINIT_EXT|\
+	/* Request the creation of an unwritten extent */
+#define EXT4_GET_BLOCKS_UNWRIT_EXT		0x0002
+#define EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT	(EXT4_GET_BLOCKS_UNWRIT_EXT|\
 						 EXT4_GET_BLOCKS_CREATE)
 	/* Caller is from the delayed allocation writeout path
 	 * finally doing the actual allocation of delayed blocks */
 #define EXT4_GET_BLOCKS_DELALLOC_RESERVE	0x0004
 	/* caller is from the direct IO path, request to creation of an
-	unitialized extents if not allocated, split the uninitialized
+	unwritten extents if not allocated, split the unwritten
 	extent if blocks has been preallocated already*/
 #define EXT4_GET_BLOCKS_PRE_IO			0x0008
 #define EXT4_GET_BLOCKS_CONVERT			0x0010
 #define EXT4_GET_BLOCKS_IO_CREATE_EXT		(EXT4_GET_BLOCKS_PRE_IO|\
-					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
+					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 	/* Convert extent to initialized after IO complete */
 #define EXT4_GET_BLOCKS_IO_CONVERT_EXT		(EXT4_GET_BLOCKS_CONVERT|\
-					 EXT4_GET_BLOCKS_CREATE_UNINIT_EXT)
+					 EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT)
 	/* Eventual metadata allocation (due to growing extent tree)
 	 * should not fail, so try to use reserved blocks for that.*/
 #define EXT4_GET_BLOCKS_METADATA_NOFAIL		0x0020
@@ -2783,10 +2782,9 @@ extern int ext4_mmp_csum_verify(struct super_block *sb,
  * See EXT4_MAP_... to see where this is used.
  */
 enum ext4_state_bits {
-	BH_Uninit	/* blocks are allocated but uninitialized on disk */
-	 = BH_JBDPrivateStart,
-	BH_AllocFromCluster,	/* allocated blocks were part of already
+	BH_AllocFromCluster	/* allocated blocks were part of already
 				 * allocated cluster. */
+	= BH_JBDPrivateStart
 };
 
 /*
diff --git a/fs/ext4/ext4_extents.h b/fs/ext4/ext4_extents.h
index 5074fe23f19e..a867f5ca9991 100644
--- a/fs/ext4/ext4_extents.h
+++ b/fs/ext4/ext4_extents.h
@@ -137,21 +137,21 @@ struct ext4_ext_path {
  * EXT_INIT_MAX_LEN is the maximum number of blocks we can have in an
  * initialized extent. This is 2^15 and not (2^16 - 1), since we use the
  * MSB of ee_len field in the extent datastructure to signify if this
- * particular extent is an initialized extent or an uninitialized (i.e.
+ * particular extent is an initialized extent or an unwritten (i.e.
  * preallocated).
- * EXT_UNINIT_MAX_LEN is the maximum number of blocks we can have in an
- * uninitialized extent.
+ * EXT_UNWRITTEN_MAX_LEN is the maximum number of blocks we can have in an
+ * unwritten extent.
  * If ee_len is <= 0x8000, it is an initialized extent. Otherwise, it is an
- * uninitialized one. In other words, if MSB of ee_len is set, it is an
- * uninitialized extent with only one special scenario when ee_len = 0x8000.
- * In this case we can not have an uninitialized extent of zero length and
+ * unwritten one. In other words, if MSB of ee_len is set, it is an
+ * unwritten extent with only one special scenario when ee_len = 0x8000.
+ * In this case we can not have an unwritten extent of zero length and
  * thus we make it as a special case of initialized extent with 0x8000 length.
  * This way we get better extent-to-group alignment for initialized extents.
  * Hence, the maximum number of blocks we can have in an *initialized*
- * extent is 2^15 (32768) and in an *uninitialized* extent is 2^15-1 (32767).
+ * extent is 2^15 (32768) and in an *unwritten* extent is 2^15-1 (32767).
  */
 #define EXT_INIT_MAX_LEN	(1UL << 15)
-#define EXT_UNINIT_MAX_LEN	(EXT_INIT_MAX_LEN - 1)
+#define EXT_UNWRITTEN_MAX_LEN	(EXT_INIT_MAX_LEN - 1)
 
 
 #define EXT_FIRST_EXTENT(__hdr__) \
@@ -187,14 +187,14 @@ static inline unsigned short ext_depth(struct inode *inode)
 	return le16_to_cpu(ext_inode_hdr(inode)->eh_depth);
 }
 
-static inline void ext4_ext_mark_uninitialized(struct ext4_extent *ext)
+static inline void ext4_ext_mark_unwritten(struct ext4_extent *ext)
 {
-	/* We can not have an uninitialized extent of zero length! */
+	/* We can not have an unwritten extent of zero length! */
 	BUG_ON((le16_to_cpu(ext->ee_len) & ~EXT_INIT_MAX_LEN) == 0);
 	ext->ee_len |= cpu_to_le16(EXT_INIT_MAX_LEN);
 }
 
-static inline int ext4_ext_is_uninitialized(struct ext4_extent *ext)
+static inline int ext4_ext_is_unwritten(struct ext4_extent *ext)
 {
 	/* Extent with ee_len of 0x8000 is treated as an initialized extent */
 	return (le16_to_cpu(ext->ee_len) > EXT_INIT_MAX_LEN);
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c
index 01b0c208f625..e305a31641f2 100644
--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -50,8 +50,8 @@
  */
 #define EXT4_EXT_MAY_ZEROOUT	0x1  /* safe to zeroout if split fails \
 					due to ENOSPC */
-#define EXT4_EXT_MARK_UNINIT1	0x2  /* mark first half uninitialized */
-#define EXT4_EXT_MARK_UNINIT2	0x4  /* mark second half uninitialized */
+#define EXT4_EXT_MARK_UNWRIT1	0x2  /* mark first half unwritten */
+#define EXT4_EXT_MARK_UNWRIT2	0x4  /* mark second half unwritten */
 
 #define EXT4_EXT_DATA_VALID1	0x8  /* first half contains valid data */
 #define EXT4_EXT_DATA_VALID2	0x10 /* second half contains valid data */
@@ -524,7 +524,7 @@ __read_extent_tree_block(const char *function, unsigned int line,
 						     lblk - prev, ~0,
 						     EXTENT_STATUS_HOLE);
 
-			if (ext4_ext_is_uninitialized(ex))
+			if (ext4_ext_is_unwritten(ex))
 				status = EXTENT_STATUS_UNWRITTEN;
 			ext4_es_cache_extent(inode, lblk, len,
 					     ext4_ext_pblock(ex), status);
@@ -620,7 +620,7 @@ static void ext4_ext_show_path(struct inode *inode, struct ext4_ext_path *path)
 		} else if (path->p_ext) {
 			ext_debug("  %d:[%d]%d:%llu ",
 				  le32_to_cpu(path->p_ext->ee_block),
-				  ext4_ext_is_uninitialized(path->p_ext),
+				  ext4_ext_is_unwritten(path->p_ext),
 				  ext4_ext_get_actual_len(path->p_ext),
 				  ext4_ext_pblock(path->p_ext));
 		} else
@@ -646,7 +646,7 @@ static void ext4_ext_show_leaf(struct inode *inode, struct ext4_ext_path *path)
 
 	for (i = 0; i < le16_to_cpu(eh->eh_entries); i++, ex++) {
 		ext_debug("%d:[%d]%d:%llu ", le32_to_cpu(ex->ee_block),
-			  ext4_ext_is_uninitialized(ex),
+			  ext4_ext_is_unwritten(ex),
 			  ext4_ext_get_actual_len(ex), ext4_ext_pblock(ex));
 	}
 	ext_debug("\n");
@@ -677,7 +677,7 @@ static void ext4_ext_show_move(struct inode *inode, struct ext4_ext_path *path,
 		ext_debug("move %d:%llu:[%d]%d in new leaf %llu\n",
 				le32_to_cpu(ex->ee_block),
 				ext4_ext_pblock(ex),
-				ext4_ext_is_uninitialized(ex),
+				ext4_ext_is_unwritten(ex),
 				ext4_ext_get_actual_len(ex),
 				newblock);
 		ex++;
@@ -802,7 +802,7 @@ ext4_ext_binsearch(struct inode *inode,
 	ext_debug("  -> %d:%llu:[%d]%d ",
 			le32_to_cpu(path->p_ext->ee_block),
 			ext4_ext_pblock(path->p_ext),
-			ext4_ext_is_uninitialized(path->p_ext),
+			ext4_ext_is_unwritten(path->p_ext),
 			ext4_ext_get_actual_len(path->p_ext));
 
 #ifdef CHECK_BINSEARCH
@@ -1686,11 +1686,11 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
 
 	/*
 	 * Make sure that both extents are initialized. We don't merge
-	 * uninitialized extents so that we can be sure that end_io code has
+	 * unwritten extents so that we can be sure that end_io code has
 	 * the extent that was written properly split out and conversion to
 	 * initialized is trivial.
 	 */
-	if (ext4_ext_is_uninitialized(ex1) != ext4_ext_is_uninitialized(ex2))
+	if (ext4_ext_is_unwritten(ex1) != ext4_ext_is_unwritten(ex2))
 		return 0;
 
 	ext1_ee_len = ext4_ext_get_actual_len(ex1);
@@ -1707,10 +1707,10 @@ ext4_can_extents_be_merged(struct inode *inode, struct ext4_extent *ex1,
 	 */
 	if (ext1_ee_len + ext2_ee_len > EXT_INIT_MAX_LEN)
 		return 0;
-	if (ext4_ext_is_uninitialized(ex1) &&
+	if (ext4_ext_is_unwritten(ex1) &&
 	    (ext4_test_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN) ||
 	     atomic_read(&EXT4_I(inode)->i_unwritten) ||
-	     (ext1_ee_len + ext2_ee_len > EXT_UNINIT_MAX_LEN)))
+	     (ext1_ee_len + ext2_ee_len > EXT_UNWRITTEN_MAX_LEN)))
 		return 0;
 #ifdef AGGRESSIVE_TEST
 	if (ext1_ee_len >= 4)
@@ -1735,7 +1735,7 @@ static int ext4_ext_try_to_merge_right(struct inode *inode,
 {
 	struct ext4_extent_header *eh;
 	unsigned int depth, len;
-	int merge_done = 0, uninit;
+	int merge_done = 0, unwritten;
 
 	depth = ext_depth(inode);
 	BUG_ON(path[depth].p_hdr == NULL);
@@ -1745,11 +1745,11 @@ static int ext4_ext_try_to_merge_right(struct inode *inode,
 		if (!ext4_can_extents_be_merged(inode, ex, ex + 1))
 			break;
 		/* merge with next extent! */
-		uninit = ext4_ext_is_uninitialized(ex);
+		unwritten = ext4_ext_is_unwritten(ex);
 		ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
 				+ ext4_ext_get_actual_len(ex + 1));
-		if (uninit)
-			ext4_ext_mark_uninitialized(ex);
+		if (unwritten)
+			ext4_ext_mark_unwritten(ex);
 
 		if (ex + 1 < EXT_LAST_EXTENT(eh)) {
 			len = (EXT_LAST_EXTENT(eh) - ex - 1)
@@ -1903,7 +1903,7 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 	struct ext4_ext_path *npath = NULL;
 	int depth, len, err;
 	ext4_lblk_t next;
-	int mb_flags = 0, uninit;
+	int mb_flags = 0, unwritten;
 
 	if (unlikely(ext4_ext_get_actual_len(newext) == 0)) {
 		EXT4_ERROR_INODE(inode, "ext4_ext_get_actual_len(newext) == 0");
@@ -1943,21 +1943,21 @@ int ext4_ext_insert_extent(handle_t *handle, struct inode *inode,
 		if (ext4_can_extents_be_merged(inode, ex, newext)) {
 			ext_debug("append [%d]%d block to %u:[%d]%d"
 				  "(from %llu)\n",
-				  ext4_ext_is_uninitialized(newext),
+				  ext4_ext_is_unwritten(newext),
 				  ext4_ext_get_actual_len(newext),
 				  le32_to_cpu(ex->ee_block),
-				  ext4_ext_is_uninitialized(ex),
+				  ext4_ext_is_unwritten(ex),
 				  ext4_ext_get_actual_len(ex),
 				  ext4_ext_pblock(ex));
 			err = ext4_ext_get_access(handle, inode,
 						  path + depth);
 			if (err)
 				return err;
-			uninit = ext4_ext_is_uninitialized(ex);
+			unwritten = ext4_ext_is_unwritten(ex);
 			ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
 					+ ext4_ext_get_actual_len(newext));
-			if (uninit)
-				ext4_ext_mark_uninitialized(ex);
+			if (unwritten)
+				ext4_ext_mark_unwritten(ex);
 			eh = path[depth].p_hdr;
 			nearex = ex;
 			goto merge;
@@ -1969,10 +1969,10 @@ prepend:
 			ext_debug("prepend %u[%d]%d block to %u:[%d]%d"
 				  "(from %llu)\n",
 				  le32_to_cpu(newext->ee_block),
-				  ext4_ext_is_uninitialized(newext),
+				  ext4_ext_is_unwritten(newext),
 				  ext4_ext_get_actual_len(newext),
 				  le32_to_cpu(ex->ee_block),
-				  ext4_ext_is_uninitialized(ex),
+				  ext4_ext_is_unwritten(ex),
 				  ext4_ext_get_actual_len(ex),
 				  ext4_ext_pblock(ex));
 			err = ext4_ext_get_access(handle, inode,
@@ -1980,13 +1980,13 @@ prepend:
 			if (err)
 				return err;
 
-			uninit = ext4_ext_is_uninitialized(ex);
+			unwritten = ext4_ext_is_unwritten(ex);
 			ex->ee_block = newext->ee_block;
 			ext4_ext_store_pblock(ex, ext4_ext_pblock(newext));
 			ex->ee_len = cpu_to_le16(ext4_ext_get_actual_len(ex)
 					+ ext4_ext_get_actual_len(newext));
-			if (uninit)
-				ext4_ext_mark_uninitialized(ex);
+			if (unwritten)
+				ext4_ext_mark_unwritten(ex);
 			eh = path[depth].p_hdr;
 			nearex = ex;
 			goto merge;
@@ -2046,7 +2046,7 @@ has_space:
 		ext_debug("first extent in the leaf: %u:%llu:[%d]%d\n",
 				le32_to_cpu(newext->ee_block),
 				ext4_ext_pblock(newext),
-				ext4_ext_is_uninitialized(newext),
+				ext4_ext_is_unwritten(newext),
 				ext4_ext_get_actual_len(newext));
 		nearex = EXT_FIRST_EXTENT(eh);
 	} else {
@@ -2057,7 +2057,7 @@ has_space:
 					"nearest %p\n",
 					le32_to_cpu(newext->ee_block),
 					ext4_ext_pblock(newext),
-					ext4_ext_is_uninitialized(newext),
+					ext4_ext_is_unwritten(newext),
 					ext4_ext_get_actual_len(newext),
 					nearex);
 			nearex++;
@@ -2068,7 +2068,7 @@ has_space:
 					"nearest %p\n",
 					le32_to_cpu(newext->ee_block),
 					ext4_ext_pblock(newext),
-					ext4_ext_is_uninitialized(newext),
+					ext4_ext_is_unwritten(newext),
 					ext4_ext_get_actual_len(newext),
 					nearex);
 		}
@@ -2078,7 +2078,7 @@ has_space:
 					"move %d extents from 0x%p to 0x%p\n",
 					le32_to_cpu(newext->ee_block),
 					ext4_ext_pblock(newext),
-					ext4_ext_is_uninitialized(newext),
+					ext4_ext_is_unwritten(newext),
 					ext4_ext_get_actual_len(newext),
 					len, nearex, nearex + 1);
 			memmove(nearex + 1, nearex,
@@ -2200,7 +2200,7 @@ static int ext4_fill_fiemap_extents(struct inode *inode,
 			es.es_lblk = le32_to_cpu(ex->ee_block);
 			es.es_len = ext4_ext_get_actual_len(ex);
 			es.es_pblk = ext4_ext_pblock(ex);
-			if (ext4_ext_is_uninitialized(ex))
+			if (ext4_ext_is_unwritten(ex))
 				flags |= FIEMAP_EXTENT_UNWRITTEN;
 		}
 
@@ -2576,7 +2576,7 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 	unsigned num;
 	ext4_lblk_t ex_ee_block;
 	unsigned short ex_ee_len;
-	unsigned uninitialized = 0;
+	unsigned unwritten = 0;
 	struct ext4_extent *ex;
 	ext4_fsblk_t pblk;
 
@@ -2623,13 +2623,13 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 	while (ex >= EXT_FIRST_EXTENT(eh) &&
 			ex_ee_block + ex_ee_len > start) {
 
-		if (ext4_ext_is_uninitialized(ex))
-			uninitialized = 1;
+		if (ext4_ext_is_unwritten(ex))
+			unwritten = 1;
 		else
-			uninitialized = 0;
+			unwritten = 0;
 
 		ext_debug("remove ext %u:[%d]%d\n", ex_ee_block,
-			 uninitialized, ex_ee_len);
+			  unwritten, ex_ee_len);
 		path[depth].p_ext = ex;
 
 		a = ex_ee_block > start ? ex_ee_block : start;
@@ -2701,11 +2701,11 @@ ext4_ext_rm_leaf(handle_t *handle, struct inode *inode,
 
 		ex->ee_len = cpu_to_le16(num);
 		/*
-		 * Do not mark uninitialized if all the blocks in the
+		 * Do not mark unwritten if all the blocks in the
 		 * extent have been removed.
 		 */
-		if (uninitialized && num)
-			ext4_ext_mark_uninitialized(ex);
+		if (unwritten && num)
+			ext4_ext_mark_unwritten(ex);
 		/*
 		 * If the extent was completely released,
 		 * we need to remove it from the leaf
@@ -2854,9 +2854,9 @@ again:
 		    end < ee_block + ext4_ext_get_actual_len(ex) - 1) {
 			int split_flag = 0;
 
-			if (ext4_ext_is_uninitialized(ex))
-				split_flag = EXT4_EXT_MARK_UNINIT1 |
-					     EXT4_EXT_MARK_UNINIT2;
+			if (ext4_ext_is_unwritten(ex))
+				split_flag = EXT4_EXT_MARK_UNWRIT1 |
+					     EXT4_EXT_MARK_UNWRIT2;
 
 			/*
 			 * Split the extent in two so that 'end' is the last
@@ -3113,7 +3113,7 @@ static int ext4_ext_zeroout(struct inode *inode, struct ext4_extent *ex)
  * @path: the path to the extent
  * @split: the logical block where the extent is splitted.
  * @split_flags: indicates if the extent could be zeroout if split fails, and
- *		 the states(init or uninit) of new extents.
+ *		 the states(init or unwritten) of new extents.
  * @flags: flags used to insert new extent to extent tree.
  *
  *
@@ -3155,10 +3155,10 @@ static int ext4_split_extent_at(handle_t *handle,
 	newblock = split - ee_block + ext4_ext_pblock(ex);
 
 	BUG_ON(split < ee_block || split >= (ee_block + ee_len));
-	BUG_ON(!ext4_ext_is_uninitialized(ex) &&
+	BUG_ON(!ext4_ext_is_unwritten(ex) &&
 	       split_flag & (EXT4_EXT_MAY_ZEROOUT |
-			     EXT4_EXT_MARK_UNINIT1 |
-			     EXT4_EXT_MARK_UNINIT2));
+			     EXT4_EXT_MARK_UNWRIT1 |
+			     EXT4_EXT_MARK_UNWRIT2));
 
 	err = ext4_ext_get_access(handle, inode, path + depth);
 	if (err)
@@ -3170,8 +3170,8 @@ static int ext4_split_extent_at(handle_t *handle,
 		 * then we just change the state of the extent, and splitting
 		 * is not needed.
 		 */
-		if (split_flag & EXT4_EXT_MARK_UNINIT2)
-			ext4_ext_mark_uninitialized(ex);
+		if (split_flag & EXT4_EXT_MARK_UNWRIT2)
+			ext4_ext_mark_unwritten(ex);
 		else
 			ext4_ext_mark_initialized(ex);
 
@@ -3185,8 +3185,8 @@ static int ext4_split_extent_at(handle_t *handle,
 	/* case a */
 	memcpy(&orig_ex, ex, sizeof(orig_ex));
 	ex->ee_len = cpu_to_le16(split - ee_block);
-	if (split_flag & EXT4_EXT_MARK_UNINIT1)
-		ext4_ext_mark_uninitialized(ex);
+	if (split_flag & EXT4_EXT_MARK_UNWRIT1)
+		ext4_ext_mark_unwritten(ex);
 
 	/*
 	 * path may lead to new leaf, not to original leaf any more
@@ -3200,8 +3200,8 @@ static int ext4_split_extent_at(handle_t *handle,
 	ex2->ee_block = cpu_to_le32(split);
 	ex2->ee_len   = cpu_to_le16(ee_len - (split - ee_block));
 	ext4_ext_store_pblock(ex2, newblock);
-	if (split_flag & EXT4_EXT_MARK_UNINIT2)
-		ext4_ext_mark_uninitialized(ex2);
+	if (split_flag & EXT4_EXT_MARK_UNWRIT2)
+		ext4_ext_mark_unwritten(ex2);
 
 	err = ext4_ext_insert_extent(handle, inode, path, &newex, flags);
 	if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) {
@@ -3278,7 +3278,7 @@ static int ext4_split_extent(handle_t *handle,
 	struct ext4_extent *ex;
 	unsigned int ee_len, depth;
 	int err = 0;
-	int uninitialized;
+	int unwritten;
 	int split_flag1, flags1;
 	int allocated = map->m_len;
 
@@ -3286,14 +3286,14 @@ static int ext4_split_extent(handle_t *handle,
 	ex = path[depth].p_ext;
 	ee_block = le32_to_cpu(ex->ee_block);
 	ee_len = ext4_ext_get_actual_len(ex);
-	uninitialized = ext4_ext_is_uninitialized(ex);
+	unwritten = ext4_ext_is_unwritten(ex);
 
 	if (map->m_lblk + map->m_len < ee_block + ee_len) {
 		split_flag1 = split_flag & EXT4_EXT_MAY_ZEROOUT;
 		flags1 = flags | EXT4_GET_BLOCKS_PRE_IO;
-		if (uninitialized)
-			split_flag1 |= EXT4_EXT_MARK_UNINIT1 |
-				       EXT4_EXT_MARK_UNINIT2;
+		if (unwritten)
+			split_flag1 |= EXT4_EXT_MARK_UNWRIT1 |
+				       EXT4_EXT_MARK_UNWRIT2;
 		if (split_flag & EXT4_EXT_DATA_VALID2)
 			split_flag1 |= EXT4_EXT_DATA_VALID1;
 		err = ext4_split_extent_at(handle, inode, path,
@@ -3318,15 +3318,15 @@ static int ext4_split_extent(handle_t *handle,
 				 (unsigned long) map->m_lblk);
 		return -EIO;
 	}
-	uninitialized = ext4_ext_is_uninitialized(ex);
+	unwritten = ext4_ext_is_unwritten(ex);
 	split_flag1 = 0;
 
 	if (map->m_lblk >= ee_block) {
 		split_flag1 = split_flag & EXT4_EXT_DATA_VALID2;
-		if (uninitialized) {
-			split_flag1 |= EXT4_EXT_MARK_UNINIT1;
+		if (unwritten) {
+			split_flag1 |= EXT4_EXT_MARK_UNWRIT1;
 			split_flag1 |= split_flag & (EXT4_EXT_MAY_ZEROOUT |
-						     EXT4_EXT_MARK_UNINIT2);
+						     EXT4_EXT_MARK_UNWRIT2);
 		}
 		err = ext4_split_extent_at(handle, inode, path,
 				map->m_lblk, split_flag1, flags);
@@ -3341,16 +3341,16 @@ out:
 
 /*
  * 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
+ * to an unwritten extent. It may result in splitting the unwritten
  * extent into multiple extents (up to three - one initialized and two
- * uninitialized).
+ * unwritten).
  * There are three possibilities:
  *   a> There is no split required: Entire extent should be initialized
  *   b> Splits in two extents: Write is happening at either end of the extent
  *   c> Splits in three extents: Somone is writing in middle of the extent
  *
  * Pre-conditions:
- *  - The extent pointed to by 'path' is uninitialized.
+ *  - The extent pointed to by 'path' is unwritten.
  *  - The extent pointed to by 'path' contains a superset
  *    of the logical span [map->m_lblk, map->m_lblk + map->m_len).
  *
@@ -3396,12 +3396,12 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 	trace_ext4_ext_convert_to_initialized_enter(inode, map, ex);
 
 	/* Pre-conditions */
-	BUG_ON(!ext4_ext_is_uninitialized(ex));
+	BUG_ON(!ext4_ext_is_unwritten(ex));
 	BUG_ON(!in_range(map->m_lblk, ee_block, ee_len));
 
 	/*
 	 * Attempt to transfer newly initialized blocks from the currently
-	 * uninitialized extent to its neighbor. This is much cheaper
+	 * unwritten extent to its neighbor. This is much cheaper
 	 * than an insertion followed by a merge as those involve costly
 	 * memmove() calls. Transferring to the left is the common case in
 	 * steady state for workloads doing fallocate(FALLOC_FL_KEEP_SIZE)
@@ -3437,7 +3437,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 		 * - C4: abut_ex can receive the additional blocks without
 		 *   overflowing the (initialized) length limit.
 		 */
-		if ((!ext4_ext_is_uninitialized(abut_ex)) &&		/*C1*/
+		if ((!ext4_ext_is_unwritten(abut_ex)) &&		/*C1*/
 			((prev_lblk + prev_len) == ee_block) &&		/*C2*/
 			((prev_pblk + prev_len) == ee_pblk) &&		/*C3*/
 			(prev_len < (EXT_INIT_MAX_LEN - map_len))) {	/*C4*/
@@ -3452,7 +3452,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 			ex->ee_block = cpu_to_le32(ee_block + map_len);
 			ext4_ext_store_pblock(ex, ee_pblk + map_len);
 			ex->ee_len = cpu_to_le16(ee_len - map_len);
-			ext4_ext_mark_uninitialized(ex); /* Restore the flag */
+			ext4_ext_mark_unwritten(ex); /* Restore the flag */
 
 			/* Extend abut_ex by 'map_len' blocks */
 			abut_ex->ee_len = cpu_to_le16(prev_len + map_len);
@@ -3483,7 +3483,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 		 * - C4: abut_ex can receive the additional blocks without
 		 *   overflowing the (initialized) length limit.
 		 */
-		if ((!ext4_ext_is_uninitialized(abut_ex)) &&		/*C1*/
+		if ((!ext4_ext_is_unwritten(abut_ex)) &&		/*C1*/
 		    ((map->m_lblk + map_len) == next_lblk) &&		/*C2*/
 		    ((ee_pblk + ee_len) == next_pblk) &&		/*C3*/
 		    (next_len < (EXT_INIT_MAX_LEN - map_len))) {	/*C4*/
@@ -3498,7 +3498,7 @@ static int ext4_ext_convert_to_initialized(handle_t *handle,
 			abut_ex->ee_block = cpu_to_le32(next_lblk - map_len);
 			ext4_ext_store_pblock(abut_ex, next_pblk - map_len);
 			ex->ee_len = cpu_to_le16(ee_len - map_len);
-			ext4_ext_mark_uninitialized(ex); /* Restore the flag */
+			ext4_ext_mark_unwritten(ex); /* Restore the flag */
 
 			/* Extend abut_ex by 'map_len' blocks */
 			abut_ex->ee_len = cpu_to_le16(next_len + map_len);
@@ -3603,26 +3603,26 @@ out:
 /*
  * This function is called by ext4_ext_map_blocks() from
  * ext4_get_blocks_dio_write() when DIO to write
- * to an uninitialized extent.
+ * to an unwritten extent.
  *
- * Writing to an uninitialized extent may result in splitting the uninitialized
- * extent into multiple initialized/uninitialized extents (up to three)
+ * Writing to an unwritten extent may result in splitting the unwritten
+ * extent into multiple initialized/unwritten extents (up to three)
  * There are three possibilities:
- *   a> There is no split required: Entire extent should be uninitialized
+ *   a> There is no split required: Entire extent should be unwritten
  *   b> Splits in two extents: Write is happening at either end of the extent
  *   c> Splits in three extents: Somone is writing in middle of the extent
  *
  * This works the same way in the case of initialized -> unwritten conversion.
  *
  * One of more index blocks maybe needed if the extent tree grow after
- * the uninitialized extent split. To prevent ENOSPC occur at the IO
- * complete, we need to split the uninitialized extent before DIO submit
- * the IO. The uninitialized extent called at this time will be split
- * into three uninitialized extent(at most). After IO complete, the part
+ * the unwritten extent split. To prevent ENOSPC occur at the IO
+ * complete, we need to split the unwritten extent before DIO submit
+ * the IO. The unwritten extent called at this time will be split
+ * into three unwritten extent(at most). After IO complete, the part
  * being filled will be convert to initialized by the end_io callback function
  * via ext4_convert_unwritten_extents().
  *
- * Returns the size of uninitialized extent to be written on success.
+ * Returns the size of unwritten extent to be written on success.
  */
 static int ext4_split_convert_extents(handle_t *handle,
 					struct inode *inode,
@@ -3660,7 +3660,7 @@ static int ext4_split_convert_extents(handle_t *handle,
 	} else if (flags & EXT4_GET_BLOCKS_CONVERT) {
 		split_flag |= ee_block + ee_len <= eof_block ?
 			      EXT4_EXT_MAY_ZEROOUT : 0;
-		split_flag |= (EXT4_EXT_MARK_UNINIT2 | EXT4_EXT_DATA_VALID2);
+		split_flag |= (EXT4_EXT_MARK_UNWRIT2 | EXT4_EXT_DATA_VALID2);
 	}
 	flags |= EXT4_GET_BLOCKS_PRE_IO;
 	return ext4_split_extent(handle, inode, path, map, split_flag, flags);
@@ -3710,8 +3710,8 @@ static int ext4_convert_initialized_extents(handle_t *handle,
 	err = ext4_ext_get_access(handle, inode, path + depth);
 	if (err)
 		goto out;
-	/* first mark the extent as uninitialized */
-	ext4_ext_mark_uninitialized(ex);
+	/* first mark the extent as unwritten */
+	ext4_ext_mark_unwritten(ex);
 
 	/* note: ext4_ext_correct_indexes() isn't needed here because
 	 * borders are not changed
@@ -3971,10 +3971,10 @@ ext4_ext_convert_initialized_extent(handle_t *handle, struct inode *inode,
 
 	/*
 	 * Make sure that the extent is no bigger than we support with
-	 * uninitialized extent
+	 * unwritten extent
 	 */
-	if (map->m_len > EXT_UNINIT_MAX_LEN)
-		map->m_len = EXT_UNINIT_MAX_LEN / 2;
+	if (map->m_len > EXT_UNWRITTEN_MAX_LEN)
+		map->m_len = EXT_UNWRITTEN_MAX_LEN / 2;
 
 	ret = ext4_convert_initialized_extents(handle, inode, map,
 						path);
@@ -3993,7 +3993,7 @@ ext4_ext_convert_initialized_extent(handle_t *handle, struct inode *inode,
 }
 
 static int
-ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
+ext4_ext_handle_unwritten_extents(handle_t *handle, struct inode *inode,
 			struct ext4_map_blocks *map,
 			struct ext4_ext_path *path, int flags,
 			unsigned int allocated, ext4_fsblk_t newblock)
@@ -4002,19 +4002,19 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
 	int err = 0;
 	ext4_io_end_t *io = ext4_inode_aio(inode);
 
-	ext_debug("ext4_ext_handle_uninitialized_extents: inode %lu, logical "
+	ext_debug("ext4_ext_handle_unwritten_extents: inode %lu, logical "
 		  "block %llu, max_blocks %u, flags %x, allocated %u\n",
 		  inode->i_ino, (unsigned long long)map->m_lblk, map->m_len,
 		  flags, allocated);
 	ext4_ext_show_leaf(inode, path);
 
 	/*
-	 * When writing into uninitialized space, we should not fail to
+	 * When writing into unwritten space, we should not fail to
 	 * allocate metadata blocks for the new extent block if needed.
 	 */
 	flags |= EXT4_GET_BLOCKS_METADATA_NOFAIL;
 
-	trace_ext4_ext_handle_uninitialized_extents(inode, map, flags,
+	trace_ext4_ext_handle_unwritten_extents(inode, map, flags,
 						    allocated, newblock);
 
 	/* get_block() before submit the IO, split the extent */
@@ -4033,8 +4033,6 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
 		else
 			ext4_set_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN);
 		map->m_flags |= EXT4_MAP_UNWRITTEN;
-		if (ext4_should_dioread_nolock(inode))
-			map->m_flags |= EXT4_MAP_UNINIT;
 		goto out;
 	}
 	/* IO end_io complete, convert the filled extent to written */
@@ -4059,7 +4057,7 @@ ext4_ext_handle_uninitialized_extents(handle_t *handle, struct inode *inode,
 	 * repeat fallocate creation request
 	 * we already have an unwritten extent
 	 */
-	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT) {
+	if (flags & EXT4_GET_BLOCKS_UNWRIT_EXT) {
 		map->m_flags |= EXT4_MAP_UNWRITTEN;
 		goto map_out;
 	}
@@ -4310,7 +4308,7 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 
 
 		/*
-		 * Uninitialized extents are treated as holes, except that
+		 * unwritten extents are treated as holes, except that
 		 * we split out initialized portions during a write.
 		 */
 		ee_len = ext4_ext_get_actual_len(ex);
@@ -4329,16 +4327,16 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 			 * If the extent is initialized check whether the
 			 * caller wants to convert it to unwritten.
 			 */
-			if ((!ext4_ext_is_uninitialized(ex)) &&
+			if ((!ext4_ext_is_unwritten(ex)) &&
 			    (flags & EXT4_GET_BLOCKS_CONVERT_UNWRITTEN)) {
 				allocated = ext4_ext_convert_initialized_extent(
 						handle, inode, map, path, flags,
 						allocated, newblock);
 				goto out2;
-			} else if (!ext4_ext_is_uninitialized(ex))
+			} else if (!ext4_ext_is_unwritten(ex))
 				goto out;
 
-			ret = ext4_ext_handle_uninitialized_extents(
+			ret = ext4_ext_handle_unwritten_extents(
 				handle, inode, map, path, flags,
 				allocated, newblock);
 			if (ret < 0)
@@ -4410,15 +4408,15 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 	/*
 	 * See if request is beyond maximum number of blocks we can have in
 	 * a single extent. For an initialized extent this limit is
-	 * EXT_INIT_MAX_LEN and for an uninitialized extent this limit is
-	 * EXT_UNINIT_MAX_LEN.
+	 * EXT_INIT_MAX_LEN and for an unwritten extent this limit is
+	 * EXT_UNWRITTEN_MAX_LEN.
 	 */
 	if (map->m_len > EXT_INIT_MAX_LEN &&
-	    !(flags & EXT4_GET_BLOCKS_UNINIT_EXT))
+	    !(flags & EXT4_GET_BLOCKS_UNWRIT_EXT))
 		map->m_len = EXT_INIT_MAX_LEN;
-	else if (map->m_len > EXT_UNINIT_MAX_LEN &&
-		 (flags & EXT4_GET_BLOCKS_UNINIT_EXT))
-		map->m_len = EXT_UNINIT_MAX_LEN;
+	else if (map->m_len > EXT_UNWRITTEN_MAX_LEN &&
+		 (flags & EXT4_GET_BLOCKS_UNWRIT_EXT))
+		map->m_len = EXT_UNWRITTEN_MAX_LEN;
 
 	/* Check if we can really insert (m_lblk)::(m_lblk + m_len) extent */
 	newex.ee_len = cpu_to_le16(map->m_len);
@@ -4466,21 +4464,19 @@ got_allocated_blocks:
 	/* try to insert new extent into found leaf and return */
 	ext4_ext_store_pblock(&newex, newblock + offset);
 	newex.ee_len = cpu_to_le16(ar.len);
-	/* Mark uninitialized */
-	if (flags & EXT4_GET_BLOCKS_UNINIT_EXT){
-		ext4_ext_mark_uninitialized(&newex);
+	/* Mark unwritten */
+	if (flags & EXT4_GET_BLOCKS_UNWRIT_EXT){
+		ext4_ext_mark_unwritten(&newex);
 		map->m_flags |= EXT4_MAP_UNWRITTEN;
 		/*
 		 * io_end structure was created for every IO write to an
-		 * uninitialized extent. To avoid unnecessary conversion,
+		 * unwritten extent. To avoid unnecessary conversion,
 		 * here we flag the IO that really needs the conversion.
 		 * For non asycn direct IO case, flag the inode state
 		 * that we need to perform conversion when IO is done.
 		 */
 		if ((flags & EXT4_GET_BLOCKS_PRE_IO))
 			set_unwritten = 1;
-		if (ext4_should_dioread_nolock(inode))
-			map->m_flags |= EXT4_MAP_UNINIT;
 	}
 
 	err = 0;
@@ -4607,9 +4603,9 @@ got_allocated_blocks:
 
 	/*
 	 * Cache the extent and update transaction to commit on fdatasync only
-	 * when it is _not_ an uninitialized extent.
+	 * when it is _not_ an unwritten extent.
 	 */
-	if ((flags & EXT4_GET_BLOCKS_UNINIT_EXT) == 0)
+	if ((flags & EXT4_GET_BLOCKS_UNWRIT_EXT) == 0)
 		ext4_update_inode_fsync_trans(handle, inode, 1);
 	else
 		ext4_update_inode_fsync_trans(handle, inode, 0);
@@ -4683,7 +4679,7 @@ static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset,
 	 * that it doesn't get unnecessarily split into multiple
 	 * extents.
 	 */
-	if (len <= EXT_UNINIT_MAX_LEN)
+	if (len <= EXT_UNWRITTEN_MAX_LEN)
 		flags |= EXT4_GET_BLOCKS_NO_NORMALIZE;
 
 	/*
@@ -4775,7 +4771,7 @@ static long ext4_zero_range(struct file *file, loff_t offset,
 	else
 		max_blocks -= lblk;
 
-	flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT |
+	flags = EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT |
 		EXT4_GET_BLOCKS_CONVERT_UNWRITTEN;
 	if (mode & FALLOC_FL_KEEP_SIZE)
 		flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
@@ -4918,7 +4914,7 @@ long ext4_fallocate(struct file *file, int mode, loff_t offset, loff_t len)
 	max_blocks = (EXT4_BLOCK_ALIGN(len + offset, blkbits) >> blkbits)
 		- lblk;
 
-	flags = EXT4_GET_BLOCKS_CREATE_UNINIT_EXT;
+	flags = EXT4_GET_BLOCKS_CREATE_UNWRIT_EXT;
 	if (mode & FALLOC_FL_KEEP_SIZE)
 		flags |= EXT4_GET_BLOCKS_KEEP_SIZE;
 
diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
index 0ebc21204b51..98c90f5834ee 100644
--- a/fs/ext4/extents_status.c
+++ b/fs/ext4/extents_status.c
@@ -433,7 +433,7 @@ static void ext4_es_insert_extent_ext_check(struct inode *inode,
 		ee_start = ext4_ext_pblock(ex);
 		ee_len = ext4_ext_get_actual_len(ex);
 
-		ee_status = ext4_ext_is_uninitialized(ex) ? 1 : 0;
+		ee_status = ext4_ext_is_unwritten(ex) ? 1 : 0;
 		es_status = ext4_es_is_unwritten(es) ? 1 : 0;
 
 		/*
diff --git a/fs/ext4/file.c b/fs/ext4/file.c
index 881394280d5f..86a13a514e4a 100644
--- a/fs/ext4/file.c
+++ b/fs/ext4/file.c
@@ -92,58 +92,91 @@ ext4_unaligned_aio(struct inode *inode, const struct iovec *iov,
 }
 
 static ssize_t
-ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
-		    unsigned long nr_segs, loff_t pos)
+ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
+		unsigned long nr_segs, loff_t pos)
 {
 	struct file *file = iocb->ki_filp;
-	struct inode *inode = file->f_mapping->host;
+	struct inode *inode = file_inode(iocb->ki_filp);
+	struct mutex *aio_mutex = NULL;
 	struct blk_plug plug;
-	int unaligned_aio = 0;
-	ssize_t ret;
+	int o_direct = file->f_flags & O_DIRECT;
 	int overwrite = 0;
 	size_t length = iov_length(iov, nr_segs);
-
-	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
-	    !is_sync_kiocb(iocb))
-		unaligned_aio = ext4_unaligned_aio(inode, iov, nr_segs, pos);
-
-	/* Unaligned direct AIO must be serialized; see comment above */
-	if (unaligned_aio) {
-		mutex_lock(ext4_aio_mutex(inode));
-		ext4_unwritten_wait(inode);
-	}
+	ssize_t ret;
 
 	BUG_ON(iocb->ki_pos != pos);
 
+	/*
+	 * Unaligned direct AIO must be serialized; see comment above
+	 * In the case of O_APPEND, assume that we must always serialize
+	 */
+	if (o_direct &&
+	    ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS) &&
+	    !is_sync_kiocb(iocb) &&
+	    (file->f_flags & O_APPEND ||
+	     ext4_unaligned_aio(inode, iov, nr_segs, pos))) {
+		aio_mutex = ext4_aio_mutex(inode);
+		mutex_lock(aio_mutex);
+		ext4_unwritten_wait(inode);
+	}
+
 	mutex_lock(&inode->i_mutex);
-	blk_start_plug(&plug);
+	if (file->f_flags & O_APPEND)
+		iocb->ki_pos = pos = i_size_read(inode);
 
-	iocb->private = &overwrite;
+	/*
+	 * If we have encountered a bitmap-format file, the size limit
+	 * is smaller than s_maxbytes, which is for extent-mapped files.
+	 */
+	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
+		struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
 
-	/* check whether we do a DIO overwrite or not */
-	if (ext4_should_dioread_nolock(inode) && !unaligned_aio &&
-	    !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
-		struct ext4_map_blocks map;
-		unsigned int blkbits = inode->i_blkbits;
-		int err, len;
+		if ((pos > sbi->s_bitmap_maxbytes) ||
+		    (pos == sbi->s_bitmap_maxbytes && length > 0)) {
+			mutex_unlock(&inode->i_mutex);
+			ret = -EFBIG;
+			goto errout;
+		}
 
-		map.m_lblk = pos >> blkbits;
-		map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
-			- map.m_lblk;
-		len = map.m_len;
+		if (pos + length > sbi->s_bitmap_maxbytes) {
+			nr_segs = iov_shorten((struct iovec *)iov, nr_segs,
+					      sbi->s_bitmap_maxbytes - pos);
+		}
+	}
 
-		err = ext4_map_blocks(NULL, inode, &map, 0);
-		/*
-		 * 'err==len' means that all of blocks has been preallocated no
-		 * matter they are initialized or not.  For excluding
-		 * uninitialized extents, we need to check m_flags.  There are
-		 * two conditions that indicate for initialized extents.
-		 * 1) If we hit extent cache, EXT4_MAP_MAPPED flag is returned;
-		 * 2) If we do a real lookup, non-flags are returned.
-		 * So we should check these two conditions.
-		 */
-		if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
-			overwrite = 1;
+	if (o_direct) {
+		blk_start_plug(&plug);
+
+		iocb->private = &overwrite;
+
+		/* check whether we do a DIO overwrite or not */
+		if (ext4_should_dioread_nolock(inode) && !aio_mutex &&
+		    !file->f_mapping->nrpages && pos + length <= i_size_read(inode)) {
+			struct ext4_map_blocks map;
+			unsigned int blkbits = inode->i_blkbits;
+			int err, len;
+
+			map.m_lblk = pos >> blkbits;
+			map.m_len = (EXT4_BLOCK_ALIGN(pos + length, blkbits) >> blkbits)
+				- map.m_lblk;
+			len = map.m_len;
+
+			err = ext4_map_blocks(NULL, inode, &map, 0);
+			/*
+			 * 'err==len' means that all of blocks has
+			 * been preallocated no matter they are
+			 * initialized or not.  For excluding
+			 * unwritten extents, we need to check
+			 * m_flags.  There are two conditions that
+			 * indicate for initialized extents.  1) If we
+			 * hit extent cache, EXT4_MAP_MAPPED flag is
+			 * returned; 2) If we do a real lookup,
+			 * non-flags are returned.  So we should check
+			 * these two conditions.
+			 */
+			if (err == len && (map.m_flags & EXT4_MAP_MAPPED))
+				overwrite = 1;
+		}
 	}
 
 	ret = __generic_file_aio_write(iocb, iov, nr_segs);
@@ -156,45 +189,12 @@ ext4_file_dio_write(struct kiocb *iocb, const struct iovec *iov,
 		if (err < 0)
 			ret = err;
 	}
-	blk_finish_plug(&plug);
-
-	if (unaligned_aio)
-		mutex_unlock(ext4_aio_mutex(inode));
-
-	return ret;
-}
-
-static ssize_t
-ext4_file_write(struct kiocb *iocb, const struct iovec *iov,
-		unsigned long nr_segs, loff_t pos)
-{
-	struct inode *inode = file_inode(iocb->ki_filp);
-	ssize_t ret;
-
-	/*
-	 * If we have encountered a bitmap-format file, the size limit
-	 * is smaller than s_maxbytes, which is for extent-mapped files.
-	 */
-
-	if (!(ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))) {
-		struct ext4_sb_info *sbi = EXT4_SB(inode->i_sb);
-		size_t length = iov_length(iov, nr_segs);
-
-		if ((pos > sbi->s_bitmap_maxbytes ||
-		    (pos == sbi->s_bitmap_maxbytes && length > 0)))
-			return -EFBIG;
-
-		if (pos + length > sbi->s_bitmap_maxbytes) {
-			nr_segs = iov_shorten((struct iovec *)iov, nr_segs,
-					      sbi->s_bitmap_maxbytes - pos);
-		}
-	}
-
-	if (unlikely(iocb->ki_filp->f_flags & O_DIRECT))
-		ret = ext4_file_dio_write(iocb, iov, nr_segs, pos);
-	else
-		ret = generic_file_aio_write(iocb, iov, nr_segs, pos);
+	if (o_direct)
+		blk_finish_plug(&plug);
 
+errout:
+	if (aio_mutex)
+		mutex_unlock(aio_mutex);
 	return ret;
 }
 
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index e5718385a037..b2cee73c1437 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -489,8 +489,8 @@ static void ext4_map_blocks_es_recheck(handle_t *handle,
  * Otherwise, call with ext4_ind_map_blocks() to handle indirect mapping
  * based files
  *
- * On success, it returns the number of blocks being mapped or allocate.
- * if create==0 and the blocks are pre-allocated and uninitialized block,
+ * On success, it returns the number of blocks being mapped or allocated.
+ * if create==0 and the blocks are pre-allocated and unwritten block,
  * the result buffer head is unmapped. If the create ==1, it will make sure
  * the buffer head is mapped.
  *
@@ -622,7 +622,7 @@ found:
 	map->m_flags &= ~EXT4_MAP_FLAGS;
 
 	/*
-	 * New blocks allocate and/or writing to uninitialized extent
+	 * New blocks allocate and/or writing to unwritten extent
 	 * will possibly result in updating i_data, so we take
 	 * the write lock of i_data_sem, and call get_blocks()
 	 * with create == 1 flag.
@@ -2032,7 +2032,7 @@ static int mpage_process_page_bufs(struct mpage_da_data *mpd,
  * Scan buffers corresponding to changed extent (we expect corresponding pages
  * to be already locked) and update buffer state according to new extent state.
  * We map delalloc buffers to their physical location, clear unwritten bits,
- * and mark buffers as uninit when we perform writes to uninitialized extents
+ * and mark buffers as uninit when we perform writes to unwritten extents
  * and do extent conversion after IO is finished. If the last page is not fully
  * mapped, we update @map to the next extent in the last page that needs
  * mapping. Otherwise we submit the page for IO.
@@ -2126,12 +2126,12 @@ static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd)
 	struct inode *inode = mpd->inode;
 	struct ext4_map_blocks *map = &mpd->map;
 	int get_blocks_flags;
-	int err;
+	int err, dioread_nolock;
 
 	trace_ext4_da_write_pages_extent(inode, map);
 	/*
 	 * Call ext4_map_blocks() to allocate any delayed allocation blocks, or
-	 * to convert an uninitialized extent to be initialized (in the case
+	 * to convert an unwritten extent to be initialized (in the case
 	 * where we have written into one or more preallocated blocks).  It is
 	 * possible that we're going to need more metadata blocks than
 	 * previously reserved. However we must not fail because we're in
@@ -2148,7 +2148,8 @@ static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd)
 	 */
 	get_blocks_flags = EXT4_GET_BLOCKS_CREATE |
 			   EXT4_GET_BLOCKS_METADATA_NOFAIL;
-	if (ext4_should_dioread_nolock(inode))
+	dioread_nolock = ext4_should_dioread_nolock(inode);
+	if (dioread_nolock)
 		get_blocks_flags |= EXT4_GET_BLOCKS_IO_CREATE_EXT;
 	if (map->m_flags & (1 << BH_Delay))
 		get_blocks_flags |= EXT4_GET_BLOCKS_DELALLOC_RESERVE;
@@ -2156,7 +2157,7 @@ static int mpage_map_one_extent(handle_t *handle, struct mpage_da_data *mpd)
 	err = ext4_map_blocks(handle, inode, map, get_blocks_flags);
 	if (err < 0)
 		return err;
-	if (map->m_flags & EXT4_MAP_UNINIT) {
+	if (dioread_nolock && (map->m_flags & EXT4_MAP_UNWRITTEN)) {
 		if (!mpd->io_submit.io_end->handle &&
 		    ext4_handle_valid(handle)) {
 			mpd->io_submit.io_end->handle = handle->h_rsv_handle;
@@ -3070,9 +3071,9 @@ static void ext4_end_io_dio(struct kiocb *iocb, loff_t offset,
  * preallocated extents, and those write extend the file, no need to
  * fall back to buffered IO.
  *
- * For holes, we fallocate those blocks, mark them as uninitialized
+ * For holes, we fallocate those blocks, mark them as unwritten
  * If those blocks were preallocated, we mark sure they are split, but
- * still keep the range to write as uninitialized.
+ * still keep the range to write as unwritten.
  *
  * The unwritten extents will be converted to written when DIO is completed.
  * For async direct IO, since the IO may still pending when return, we
@@ -3123,12 +3124,12 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb,
 	 * We could direct write to holes and fallocate.
 	 *
 	 * Allocated blocks to fill the hole are marked as
-	 * uninitialized to prevent parallel buffered read to expose
+	 * unwritten to prevent parallel buffered read to expose
 	 * the stale data before DIO complete the data IO.
 	 *
 	 * As to previously fallocated extents, ext4 get_block will
 	 * just simply mark the buffer mapped but still keep the
-	 * extents uninitialized.
+	 * extents unwritten.
 	 *
 	 * For non AIO case, we will convert those unwritten extents
 	 * to written after return back from blockdev_direct_IO.
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index 58ee7dc87669..1b809fe51da1 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -57,8 +57,8 @@ get_ext_path(struct inode *inode, ext4_lblk_t lblock,
 static void
 copy_extent_status(struct ext4_extent *src, struct ext4_extent *dest)
 {
-	if (ext4_ext_is_uninitialized(src))
-		ext4_ext_mark_uninitialized(dest);
+	if (ext4_ext_is_unwritten(src))
+		ext4_ext_mark_unwritten(dest);
 	else
 		dest->ee_len = cpu_to_le16(ext4_ext_get_actual_len(dest));
 }
@@ -593,14 +593,14 @@ mext_calc_swap_extents(struct ext4_extent *tmp_dext,
  * @inode:		inode in question
  * @from:		block offset of inode
  * @count:		block count to be checked
- * @uninit:		extents expected to be uninitialized
+ * @unwritten:		extents expected to be unwritten
  * @err:		pointer to save error value
  *
  * Return 1 if all extents in range has expected type, and zero otherwise.
  */
 static int
 mext_check_coverage(struct inode *inode, ext4_lblk_t from, ext4_lblk_t count,
-			  int uninit, int *err)
+		    int unwritten, int *err)
 {
 	struct ext4_ext_path *path = NULL;
 	struct ext4_extent *ext;
@@ -611,7 +611,7 @@ mext_check_coverage(struct inode *inode, ext4_lblk_t from, ext4_lblk_t count,
 		if (*err)
 			goto out;
 		ext = path[ext_depth(inode)].p_ext;
-		if (uninit != ext4_ext_is_uninitialized(ext))
+		if (unwritten != ext4_ext_is_unwritten(ext))
 			goto out;
 		from += ext4_ext_get_actual_len(ext);
 		ext4_ext_drop_refs(path);
@@ -894,7 +894,7 @@ out:
  * @orig_page_offset:		page index on original file
  * @data_offset_in_page:	block index where data swapping starts
  * @block_len_in_page:		the number of blocks to be swapped
- * @uninit:			orig extent is uninitialized or not
+ * @unwritten:			orig extent is unwritten or not
  * @err:			pointer to save return value
  *
  * Save the data in original inode blocks and replace original inode extents
@@ -905,7 +905,7 @@ out:
 static int
 move_extent_per_page(struct file *o_filp, struct inode *donor_inode,
 		  pgoff_t orig_page_offset, int data_offset_in_page,
-		  int block_len_in_page, int uninit, int *err)
+		  int block_len_in_page, int unwritten, int *err)
 {
 	struct inode *orig_inode = file_inode(o_filp);
 	struct page *pagep[2] = {NULL, NULL};
@@ -962,27 +962,27 @@ again:
 	if (unlikely(*err < 0))
 		goto stop_journal;
 	/*
-	 * If orig extent was uninitialized it can become initialized
+	 * If orig extent was unwritten it can become initialized
 	 * at any time after i_data_sem was dropped, in order to
 	 * serialize with delalloc we have recheck extent while we
 	 * hold page's lock, if it is still the case data copy is not
 	 * necessary, just swap data blocks between orig and donor.
 	 */
-	if (uninit) {
+	if (unwritten) {
 		ext4_double_down_write_data_sem(orig_inode, donor_inode);
 		/* If any of extents in range became initialized we have to
 		 * fallback to data copying */
-		uninit = mext_check_coverage(orig_inode, orig_blk_offset,
-					     block_len_in_page, 1, err);
+		unwritten = mext_check_coverage(orig_inode, orig_blk_offset,
+						block_len_in_page, 1, err);
 		if (*err)
 			goto drop_data_sem;
 
-		uninit &= mext_check_coverage(donor_inode, orig_blk_offset,
-					      block_len_in_page, 1, err);
+		unwritten &= mext_check_coverage(donor_inode, orig_blk_offset,
+						 block_len_in_page, 1, err);
 		if (*err)
 			goto drop_data_sem;
 
-		if (!uninit) {
+		if (!unwritten) {
 			ext4_double_up_write_data_sem(orig_inode, donor_inode);
 			goto data_copy;
 		}
@@ -1259,7 +1259,7 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp,
 	int blocks_per_page = PAGE_CACHE_SIZE >> orig_inode->i_blkbits;
 	int data_offset_in_page;
 	int block_len_in_page;
-	int uninit;
+	int unwritten;
 
 	if (orig_inode->i_sb != donor_inode->i_sb) {
 		ext4_debug("ext4 move extent: The argument files "
@@ -1391,8 +1391,8 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp,
 		    !last_extent)
 			continue;
 
-		/* Is original extent is uninitialized */
-		uninit = ext4_ext_is_uninitialized(ext_prev);
+		/* Is original extent is unwritten */
+		unwritten = ext4_ext_is_unwritten(ext_prev);
 
 		data_offset_in_page = seq_start % blocks_per_page;
 
@@ -1432,8 +1432,8 @@ ext4_move_extents(struct file *o_filp, struct file *d_filp,
 						o_filp, donor_inode,
 						orig_page_offset,
 						data_offset_in_page,
-						block_len_in_page, uninit,
-						&ret);
+						block_len_in_page,
+						unwritten, &ret);
 
 			/* Count how many blocks we have exchanged */
 			*moved_len += block_len_in_page;
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 6f9e6fadac04..c4895c195e00 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3337,7 +3337,7 @@ static ext4_fsblk_t ext4_calculate_resv_clusters(struct super_block *sb)
 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
 	 * This should cover the situations where we can not afford to run
 	 * out of space like for example punch hole, or converting
-	 * uninitialized extents in delalloc path. In most cases such
+	 * unwritten extents in delalloc path. In most cases such
 	 * allocation would require 1, or 2 blocks, higher numbers are
 	 * very rare.
 	 */
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index 6a1a0245474f..d4f70a7fe876 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -36,7 +36,7 @@ struct extent_status;
 
 #define show_map_flags(flags) __print_flags(flags, "|",			\
 	{ EXT4_GET_BLOCKS_CREATE,		"CREATE" },		\
-	{ EXT4_GET_BLOCKS_UNINIT_EXT,		"UNINIT" },		\
+	{ EXT4_GET_BLOCKS_UNWRIT_EXT,		"UNWRIT" },		\
 	{ EXT4_GET_BLOCKS_DELALLOC_RESERVE,	"DELALLOC" },		\
 	{ EXT4_GET_BLOCKS_PRE_IO,		"PRE_IO" },		\
 	{ EXT4_GET_BLOCKS_CONVERT,		"CONVERT" },		\
@@ -51,7 +51,6 @@ struct extent_status;
 	{ EXT4_MAP_MAPPED,	"M" },			\
 	{ EXT4_MAP_UNWRITTEN,	"U" },			\
 	{ EXT4_MAP_BOUNDARY,	"B" },			\
-	{ EXT4_MAP_UNINIT,	"u" },			\
 	{ EXT4_MAP_FROM_CLUSTER, "C" })
 
 #define show_free_flags(flags) __print_flags(flags, "|",	\
@@ -1497,7 +1496,7 @@ DEFINE_EVENT(ext4__truncate, ext4_truncate_exit,
 	TP_ARGS(inode)
 );
 
-/* 'ux' is the uninitialized extent. */
+/* 'ux' is the unwritten extent. */
 TRACE_EVENT(ext4_ext_convert_to_initialized_enter,
 	TP_PROTO(struct inode *inode, struct ext4_map_blocks *map,
 		 struct ext4_extent *ux),
@@ -1533,7 +1532,7 @@ TRACE_EVENT(ext4_ext_convert_to_initialized_enter,
 );
 
 /*
- * 'ux' is the uninitialized extent.
+ * 'ux' is the unwritten extent.
  * 'ix' is the initialized extent to which blocks are transferred.
  */
 TRACE_EVENT(ext4_ext_convert_to_initialized_fastpath,
@@ -1811,7 +1810,7 @@ DEFINE_EVENT(ext4__trim, ext4_trim_all_free,
 	TP_ARGS(sb, group, start, len)
 );
 
-TRACE_EVENT(ext4_ext_handle_uninitialized_extents,
+TRACE_EVENT(ext4_ext_handle_unwritten_extents,
 	TP_PROTO(struct inode *inode, struct ext4_map_blocks *map, int flags,
 		 unsigned int allocated, ext4_fsblk_t newblock),