From: qwang12 <qwang12@6f19259b-4bc3-4df7-8a09-765794883524>
Date: Tue, 10 Oct 2006 02:21:51 +0000 (+0000)
Subject: This patch is to make sure at least VARIABLE_RECLAIM_THRESHOLD (1024) bytes of spaces... 
X-Git-Tag: edk2-stable201903~24177
X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=c65c1e1e1428a1a7c41a3b89a84383aa15624c7a

This patch is to make sure at least VARIABLE_RECLAIM_THRESHOLD (1024) bytes of spaces must be available in NV variable region. This conservative approach is make sure OS loader will have space to save important data.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@1697 6f19259b-4bc3-4df7-8a09-765794883524
---

diff --git a/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index a9505d903c..d575417fe9 100644
--- a/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -1388,6 +1388,23 @@ Returns:
 
     mVariableModuleGlobal->NonVolatileLastVariableOffset = (UINTN) NextVariable - (UINTN) CurrPtr;
 
+    //
+    // Check if the free area is blow a threshold
+    //
+    if ((((VARIABLE_STORE_HEADER *)((UINTN) CurrPtr))->Size - mVariableModuleGlobal->NonVolatileLastVariableOffset) < VARIABLE_RECLAIM_THRESHOLD) {
+      Status = Reclaim (
+                mVariableModuleGlobal->VariableBase[Physical].NonVolatileVariableBase,
+                &mVariableModuleGlobal->NonVolatileLastVariableOffset,
+                FALSE
+                );
+    }
+
+    if (EFI_ERROR (Status)) {
+      gBS->FreePool (mVariableModuleGlobal);
+      gBS->FreePool (VolatileVariableStore);
+      return Status;
+    }
+
     //
     // Check if the free area is really free.
     //
diff --git a/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.h b/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.h
index 55423a25b9..014df50c3d 100644
--- a/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.h
+++ b/EdkModulePkg/Universal/Variable/RuntimeDxe/Variable.h
@@ -35,6 +35,7 @@ Abstract:
 #define ALIGNMENT  1
 #endif
 
+#define VARIABLE_RECLAIM_THRESHOLD (1024)
 
 #define VARIABLE_STORE_SIZE (64 * 1024)
 #define SCRATCH_SIZE        (4 * 1024)