diff --git a/fs/btrfs/extent_map.c b/fs/btrfs/extent_map.c
index 955ce300e5a1..dd51a21b6a76 100644
--- a/fs/btrfs/extent_map.c
+++ b/fs/btrfs/extent_map.c
@@ -759,14 +759,14 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 					split->block_len = em->block_len;
 				else
 					split->block_len = split->len;
-				split->orig_block_len = max(split->block_len,
-						em->orig_block_len);
+				split->disk_num_bytes = max(split->block_len,
+							    em->disk_num_bytes);
 				split->ram_bytes = em->ram_bytes;
 			} else {
 				split->orig_start = split->start;
 				split->block_len = 0;
 				split->block_start = em->block_start;
-				split->orig_block_len = 0;
+				split->disk_num_bytes = 0;
 				split->ram_bytes = split->len;
 			}
 
@@ -791,8 +791,8 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 			split->generation = gen;
 
 			if (em->block_start < EXTENT_MAP_LAST_BYTE) {
-				split->orig_block_len = max(em->block_len,
-						    em->orig_block_len);
+				split->disk_num_bytes = max(em->block_len,
+							    em->disk_num_bytes);
 
 				split->ram_bytes = em->ram_bytes;
 				if (compressed) {
@@ -809,7 +809,7 @@ void btrfs_drop_extent_map_range(struct btrfs_inode *inode, u64 start, u64 end,
 				split->ram_bytes = split->len;
 				split->orig_start = split->start;
 				split->block_len = 0;
-				split->orig_block_len = 0;
+				split->disk_num_bytes = 0;
 			}
 
 			if (extent_map_in_tree(em)) {
@@ -968,7 +968,7 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	split_pre->orig_start = split_pre->start;
 	split_pre->block_start = new_logical;
 	split_pre->block_len = split_pre->len;
-	split_pre->orig_block_len = split_pre->block_len;
+	split_pre->disk_num_bytes = split_pre->block_len;
 	split_pre->ram_bytes = split_pre->len;
 	split_pre->flags = flags;
 	split_pre->generation = em->generation;
@@ -986,7 +986,7 @@ int split_extent_map(struct btrfs_inode *inode, u64 start, u64 len, u64 pre,
 	split_mid->orig_start = split_mid->start;
 	split_mid->block_start = em->block_start + pre;
 	split_mid->block_len = split_mid->len;
-	split_mid->orig_block_len = split_mid->block_len;
+	split_mid->disk_num_bytes = split_mid->block_len;
 	split_mid->ram_bytes = split_mid->len;
 	split_mid->flags = flags;
 	split_mid->generation = em->generation;
diff --git a/fs/btrfs/extent_map.h b/fs/btrfs/extent_map.h
index 0b938e12cc78..242a0c2e7a5e 100644
--- a/fs/btrfs/extent_map.h
+++ b/fs/btrfs/extent_map.h
@@ -71,7 +71,7 @@ struct extent_map {
 	 * The full on-disk extent length, matching
 	 * btrfs_file_extent_item::disk_num_bytes.
 	 */
-	u64 orig_block_len;
+	u64 disk_num_bytes;
 
 	/*
 	 * The decompressed size of the whole on-disk extent, matching
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 844439f19949..b552646a0ce6 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -1280,7 +1280,7 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 		em->len = btrfs_file_extent_end(path) - extent_start;
 		em->orig_start = extent_start -
 			btrfs_file_extent_offset(leaf, fi);
-		em->orig_block_len = btrfs_file_extent_disk_num_bytes(leaf, fi);
+		em->disk_num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
 		bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
 		if (bytenr == 0) {
 			em->block_start = EXTENT_MAP_HOLE;
@@ -1289,7 +1289,7 @@ void btrfs_extent_item_to_extent_map(struct btrfs_inode *inode,
 		if (compress_type != BTRFS_COMPRESS_NONE) {
 			extent_map_set_compression(em, compress_type);
 			em->block_start = bytenr;
-			em->block_len = em->orig_block_len;
+			em->block_len = em->disk_num_bytes;
 		} else {
 			bytenr += btrfs_file_extent_offset(leaf, fi);
 			em->block_start = bytenr;
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index 0c23053951be..cdcd7e0785c1 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -2162,7 +2162,7 @@ static int fill_holes(struct btrfs_trans_handle *trans,
 
 		hole_em->block_start = EXTENT_MAP_HOLE;
 		hole_em->block_len = 0;
-		hole_em->orig_block_len = 0;
+		hole_em->disk_num_bytes = 0;
 		hole_em->generation = trans->transid;
 
 		ret = btrfs_replace_extent_map_range(inode, hole_em, true);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index ced916f42bab..2e0156943c7c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4991,7 +4991,7 @@ int btrfs_cont_expand(struct btrfs_inode *inode, loff_t oldsize, loff_t size)
 
 			hole_em->block_start = EXTENT_MAP_HOLE;
 			hole_em->block_len = 0;
-			hole_em->orig_block_len = 0;
+			hole_em->disk_num_bytes = 0;
 			hole_em->ram_bytes = hole_size;
 			hole_em->generation = btrfs_get_fs_generation(fs_info);
 
@@ -7313,7 +7313,7 @@ static int lock_extent_direct(struct inode *inode, u64 lockstart, u64 lockend,
 /* The callers of this must take lock_extent() */
 static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
 				       u64 len, u64 orig_start, u64 block_start,
-				       u64 block_len, u64 orig_block_len,
+				       u64 block_len, u64 disk_num_bytes,
 				       u64 ram_bytes, int compress_type,
 				       int type)
 {
@@ -7345,7 +7345,7 @@ static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
 		ASSERT(block_len == len);
 
 		/* COW results a new extent matching our file extent size. */
-		ASSERT(orig_block_len == len);
+		ASSERT(disk_num_bytes == len);
 		ASSERT(ram_bytes == len);
 
 		/* Since it's a new extent, we should not have any offset. */
@@ -7372,7 +7372,7 @@ static struct extent_map *create_io_em(struct btrfs_inode *inode, u64 start,
 	em->len = len;
 	em->block_len = block_len;
 	em->block_start = block_start;
-	em->orig_block_len = orig_block_len;
+	em->disk_num_bytes = disk_num_bytes;
 	em->ram_bytes = ram_bytes;
 	em->generation = -1;
 	em->flags |= EXTENT_FLAG_PINNED;
@@ -9776,7 +9776,7 @@ static int __btrfs_prealloc_file_range(struct inode *inode, int mode,
 		em->len = ins.offset;
 		em->block_start = ins.objectid;
 		em->block_len = ins.offset;
-		em->orig_block_len = ins.offset;
+		em->disk_num_bytes = ins.offset;
 		em->ram_bytes = ins.offset;
 		em->flags |= EXTENT_FLAG_PREALLOC;
 		em->generation = trans->transid;
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index d9777649e170..2a13ca1eb7c5 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -2872,7 +2872,7 @@ static inline void btrfs_remove_log_ctx(struct btrfs_root *root,
 	mutex_unlock(&root->log_mutex);
 }
 
-/* 
+/*
  * Invoked in log mutex context, or be sure there is no other task which
  * can access the list.
  */
@@ -4645,7 +4645,7 @@ static int log_extent_csums(struct btrfs_trans_handle *trans,
 	/* If we're compressed we have to save the entire range of csums. */
 	if (extent_map_is_compressed(em)) {
 		csum_offset = 0;
-		csum_len = max(em->block_len, em->orig_block_len);
+		csum_len = max(em->block_len, em->disk_num_bytes);
 	} else {
 		csum_offset = mod_start - em->start;
 		csum_len = mod_len;
@@ -4694,7 +4694,7 @@ static int log_one_extent(struct btrfs_trans_handle *trans,
 	else
 		btrfs_set_stack_file_extent_type(&fi, BTRFS_FILE_EXTENT_REG);
 
-	block_len = max(em->block_len, em->orig_block_len);
+	block_len = max(em->block_len, em->disk_num_bytes);
 	compress_type = extent_map_compression(em);
 	if (compress_type != BTRFS_COMPRESS_NONE) {
 		btrfs_set_stack_file_extent_disk_bytenr(&fi, em->block_start);
