diff --git a/drawing/FileSystem.lua b/drawing/FileSystem.lua
index e16e9dd..7e95ce6 100644
--- a/drawing/FileSystem.lua
+++ b/drawing/FileSystem.lua
@@ -1,87 +1,90 @@
-local Line 			= require 'Line'
-local Util			= require 'Util'
-local Common		= require 'Common'
+local Line = require 'Line'
+local Util = require 'Util'
+local Common = require 'Common'
 local Geometry = require 'Geometry'
 
-local _FS_PATHS_ = {'/', '/boot', '/home', '/mnt/data', '/mnt/dcache', "/tmp"}
-local _MODULE_Y_ = 170
-local _SPACING_ = 20
-local _BAR_PAD_ = 100
-local _SEPARATOR_SPACING_ = 20
-
-local FS_NUM = #_FS_PATHS_
-
-local header = Common.Header(
-	Geometry.RIGHT_X,
-	_MODULE_Y_,
-	Geometry.SECTION_WIDTH,
-	'FILE SYSTEMS'
-)
-
-local conky_used_perc = {}
-
-for i, v in pairs(_FS_PATHS_) do
-	conky_used_perc[i] = '${fs_used_perc '..v..'}'
-end
-
-local smart = Common.initTextRow(
-   Geometry.RIGHT_X,
-   header.bottom_y,
-   Geometry.SECTION_WIDTH,
-   'SMART Daemon'
-)
-
-local _SEP_Y_ = header.bottom_y + _SEPARATOR_SPACING_
-
-local separator = Common.initSeparator(
-   Geometry.RIGHT_X,
-   _SEP_Y_,
-   Geometry.SECTION_WIDTH
-)
-
-local _BAR_Y_ = _SEP_Y_ + _SEPARATOR_SPACING_
-
-local fs = Common.compound_bar(
-   Geometry.RIGHT_X,
-   _BAR_Y_,
-   Geometry.SECTION_WIDTH,
-   _BAR_PAD_,
-   {'root', 'boot', 'home', 'data', 'dcache', 'tmpfs'},
-   _SPACING_,
-   12,
-   0.8
-)
-
-_SPACING_ = nil
-_BAR_PAD_ = nil
-_FS_PATHS_ = nil
-_SEPARATOR_SPACING_ = nil
-_BAR_Y_ = nil
-_SEP_Y_ = nil
-
-local update = function(cr)
-   local smart_pid = Util.execute_cmd('pidof smartd', nil, '*n')
-   Common.text_row_set(smart, cr, (smart_pid == '') and 'Error' or 'Running')
-
-   for i = 1, FS_NUM do
-      local percent = Util.conky_numeric(conky_used_perc[i])
-      Common.compound_bar_set(fs, i, percent * 0.01)
-   end
-end
-
-local draw_static = function(cr)
-   Common.drawHeader(cr, header)
-   Common.text_row_draw_static(smart, cr)
-   Line.draw(separator, cr)
-   Common.compound_bar_draw_static(fs, cr)
-end
-
-local draw_dynamic = function(cr, trigger)
-   if trigger == 0 then update(cr) end
-   Common.text_row_draw_dynamic(smart, cr)
-   Common.compound_bar_draw_dynamic(fs, cr)
-end
-
 return function()
+   local FS_PATHS = {'/', '/boot', '/home', '/mnt/data', '/mnt/dcache', "/tmp"}
+   local MODULE_Y = 170
+   local SPACING = 20
+   local BAR_PAD = 100
+   local SEPARATOR_SPACING = 20
+
+   -----------------------------------------------------------------------------
+   -- header
+
+   local header = Common.Header(
+      Geometry.RIGHT_X,
+      MODULE_Y,
+      Geometry.SECTION_WIDTH,
+      'FILE SYSTEMS'
+   )
+
+   -----------------------------------------------------------------------------
+   -- smartd
+
+   local smart = Common.initTextRow(
+      Geometry.RIGHT_X,
+      header.bottom_y,
+      Geometry.SECTION_WIDTH,
+      'SMART Daemon'
+   )
+
+   local SEP_Y = header.bottom_y + SEPARATOR_SPACING
+
+   local separator = Common.initSeparator(
+      Geometry.RIGHT_X,
+      SEP_Y,
+      Geometry.SECTION_WIDTH
+   )
+
+   -----------------------------------------------------------------------------
+   -- filesystem bar chart
+
+   local BAR_Y = SEP_Y + SEPARATOR_SPACING
+
+   local fs = Common.compound_bar(
+      Geometry.RIGHT_X,
+      BAR_Y,
+      Geometry.SECTION_WIDTH,
+      BAR_PAD,
+      {'root', 'boot', 'home', 'data', 'dcache', 'tmpfs'},
+      SPACING,
+      12,
+      0.8
+   )
+
+   local FS_NUM = #FS_PATHS
+   local CONKY_USED_PERC = {}
+   for i, v in pairs(FS_PATHS) do
+      CONKY_USED_PERC[i] = '${fs_used_perc '..v..'}'
+   end
+
+   -----------------------------------------------------------------------------
+   -- main functions
+
+   local update = function(cr)
+      local smart_pid = Util.execute_cmd('pidof smartd', nil, '*n')
+      Common.text_row_set(smart, cr, (smart_pid == '') and 'Error' or 'Running')
+
+      for i = 1, FS_NUM do
+         local percent = Util.conky_numeric(CONKY_USED_PERC[i])
+         Common.compound_bar_set(fs, i, percent * 0.01)
+      end
+   end
+
+   local draw_static = function(cr)
+      Common.drawHeader(cr, header)
+      Common.text_row_draw_static(smart, cr)
+      Line.draw(separator, cr)
+      Common.compound_bar_draw_static(fs, cr)
+   end
+
+   local draw_dynamic = function(cr, trigger)
+      if trigger == 0 then update(cr) end
+      Common.text_row_draw_dynamic(smart, cr)
+      Common.compound_bar_draw_dynamic(fs, cr)
+   end
+
    return {static = draw_static, dynamic = draw_dynamic}
 end