MdeModulePkg Variable: Introduce PcdReclaimVariableSpaceAtEndOfDxe

for trying to reclaim variable space at EndOfDxe.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16687 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/MdeModulePkg.dec

@@ -738,6 +738,12 @@
   # @Prompt Boottime reserved NV variable space size.
   gEfiMdeModulePkgTokenSpaceGuid.PcdBoottimeReservedNvVariableSpaceSize|0x00|UINT32|0x30000007
 
+  ## Reclaim variable space at EndOfDxe.<BR><BR>
+  # The value is FALSE as default for compatibility that variable driver tries to reclaim variable space at ReadyToBoot event.<BR>
+  # If the value is set to TRUE, variable driver tries to reclaim variable space at EndOfDxe event.<BR>
+  # @Prompt Reclaim variable space at EndOfDxe.
+  gEfiMdeModulePkgTokenSpaceGuid.PcdReclaimVariableSpaceAtEndOfDxe|FALSE|BOOLEAN|0x30000008
+
   ## The size of volatile buffer. This buffer is used to store VOLATILE attribute variables.
   # @Prompt Variable storage size.
   gEfiMdeModulePkgTokenSpaceGuid.PcdVariableStoreSize|0x10000|UINT32|0x30000005

MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c

@@ -3124,6 +3124,15 @@ ReclaimForOS(
   EFI_STATUS                     Status;
   UINTN                          RemainingCommonRuntimeVariableSpace;
   UINTN                          RemainingHwErrVariableSpace;
+  STATIC BOOLEAN                 Reclaimed;
+
+  //
+  // This function will be called only once at EndOfDxe or ReadyToBoot event.
+  //
+  if (Reclaimed) {
+    return;
+  }
+  Reclaimed = TRUE;
 
   Status  = EFI_SUCCESS;
 

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableDxe.c

@@ -313,6 +313,9 @@ OnEndOfDxe (
   // The initialization for variable quota.
   //
   InitializeVariableQuota ();
+  if (PcdGetBool (PcdReclaimVariableSpaceAtEndOfDxe)) {
+    ReclaimForOS ();
+  }
 }
 
 /**

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableRuntimeDxe.inf

@@ -103,7 +103,8 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdHwErrStorageSize                ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxUserNvVariableSpaceSize           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdBoottimeReservedNvVariableSpaceSize  ## CONSUMES
-  
+  gEfiMdeModulePkgTokenSpaceGuid.PcdReclaimVariableSpaceAtEndOfDxe  ## CONSUMES
+
 [FeaturePcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdVariableCollectStatistics  ## CONSUMES # statistic the information of variable.
   gEfiMdePkgTokenSpaceGuid.PcdUefiVariableDefaultLangDeprecate ## CONSUMES

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c

@@ -832,6 +832,9 @@ SmmEndOfDxeCallback (
   // The initialization for variable quota.
   //
   InitializeVariableQuota ();
+  if (PcdGetBool (PcdReclaimVariableSpaceAtEndOfDxe)) {
+    ReclaimForOS ();
+  }
   return EFI_SUCCESS;
 }
 

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.inf

@@ -105,7 +105,8 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdHwErrStorageSize                ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdMaxUserNvVariableSpaceSize           ## CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdBoottimeReservedNvVariableSpaceSize  ## CONSUMES
-  
+  gEfiMdeModulePkgTokenSpaceGuid.PcdReclaimVariableSpaceAtEndOfDxe  ## CONSUMES
+
 [FeaturePcd]
   gEfiMdeModulePkgTokenSpaceGuid.PcdVariableCollectStatistics   ## CONSUMES # statistic the information of variable.
   gEfiMdePkgTokenSpaceGuid.PcdUefiVariableDefaultLangDeprecate  ## CONSUMES