diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 84e7f1d00a83946a69ca345477c8908ce3131c0f..e227eea23f052c063547b5e4cd6a8b7a5ba59801 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -476,7 +476,6 @@ struct move_extent {
 	__u64 len;		/* block length to be moved */
 	__u64 moved_len;	/* moved block length */
 };
-#define MAX_DEFRAG_SIZE         ((1UL<<31) - 1)
 
 #define EXT4_EPOCH_BITS 2
 #define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1)
diff --git a/fs/ext4/ext4_extents.h b/fs/ext4/ext4_extents.h
index 9538633879d77935373ab340bbff7f875869c991..61652f1d15e67cdc945b9de935550d189ce33b56 100644
--- a/fs/ext4/ext4_extents.h
+++ b/fs/ext4/ext4_extents.h
@@ -137,6 +137,7 @@ typedef int (*ext_prepare_callback)(struct inode *, struct ext4_ext_path *,
 #define EXT_BREAK      1
 #define EXT_REPEAT     2
 
+/* Maximum logical block in a file; ext4_extent's ee_block is __le32 */
 #define EXT_MAX_BLOCK	0xffffffff
 
 /*
diff --git a/fs/ext4/move_extent.c b/fs/ext4/move_extent.c
index 1f027b1ec430b7a905752fcb7f5310dbb42f68eb..c07a2915e40b63d0bf5e0ffa4ad08146e2749e36 100644
--- a/fs/ext4/move_extent.c
+++ b/fs/ext4/move_extent.c
@@ -1040,12 +1040,12 @@ mext_check_arguments(struct inode *orig_inode,
 		return -EINVAL;
 	}
 
-	if ((orig_start > MAX_DEFRAG_SIZE) ||
-	    (donor_start > MAX_DEFRAG_SIZE) ||
-	    (*len > MAX_DEFRAG_SIZE) ||
-	    (orig_start + *len > MAX_DEFRAG_SIZE))  {
-		ext4_debug("ext4 move extent: Can't handle over [%lu] blocks "
-			"[ino:orig %lu, donor %lu]\n", MAX_DEFRAG_SIZE,
+	if ((orig_start > EXT_MAX_BLOCK) ||
+	    (donor_start > EXT_MAX_BLOCK) ||
+	    (*len > EXT_MAX_BLOCK) ||
+	    (orig_start + *len > EXT_MAX_BLOCK))  {
+		ext4_debug("ext4 move extent: Can't handle over [%u] blocks "
+			"[ino:orig %lu, donor %lu]\n", EXT_MAX_BLOCK,
 			orig_inode->i_ino, donor_inode->i_ino);
 		return -EINVAL;
 	}