improve mount subvolume

modules/btrfs.mod

@@ -94,7 +94,11 @@ sudo /bin/find $1 -maxdepth $2 -type d -exec sh -c '
 #      ' find-sh {} + \) \)
 
 mount_subvolume () {
+  echo sudo mount $1 -o subvol=$2 $3
+  if mountpoint $3; then
+  echo $3 already a mountpoint, aborting subvolume mount
+  else
   mkdir -p $3
-  echo msudo mount $1 -o subvol=$2 $3
   sudo mount $1 -o subvol=$2 $3
+  fi
 }