diff --git a/src/tfs/src/tdisk.c b/src/tfs/src/tdisk.c
index 7cdaf7fd099db85c988077296ade2da7440be8a1..37798d3a886b443a20703747ad9a99e26c1502b7 100644
--- a/src/tfs/src/tdisk.c
+++ b/src/tfs/src/tdisk.c
@@ -52,7 +52,7 @@ int tfsUpdateDiskInfo(SDisk *pDisk) {
   }
 
   pDisk->dmeta.size = diskSize.tsize;
-  pDisk->dmeta.free = diskSize.tsize - diskSize.avail;
+  pDisk->dmeta.free = diskSize.avail;
 
   return code;
-}
\ No newline at end of file
+}