MdeMoudlePkg/CapsulePei: Optimize GetScatterGatherHeadEntries

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1853

Rename the MACRO from MAX_SG_LIST_HEADS to DEFAULT_SG_LIST_HEADS.
GetScatterGatherHeadEntries: use allocated buffer instead of fixed
array to handle the condition which the SG list is larger then the
array size.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Michael Turner <Michael.Turner@microsoft.com>
Cc: Bret Barkelew <Bret.Barkelew@microsoft.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Zhichao gao <zhichao.gao@intel.com>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>

1 files changed, 37 insertions, 14 deletions

diff --git a/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c b/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c
index ce6d95a..3ac95b7 100644
--- a/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c
+++ b/MdeModulePkg/Universal/CapsulePei/UefiCapsule.c
@@ -10,6 +10,8 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 

 #include "Capsule.h"

 

+#define DEFAULT_SG_LIST_HEADS       (20)

+

 #ifdef MDE_CPU_IA32

 //

 // Global Descriptor Table (GDT)

@@ -841,8 +843,6 @@ AreCapsulesStaged (
   return FALSE;

 }

 

-#define MAX_SG_LIST_HEADS (20)

-

 /**

   Check all the variables for SG list heads and get the count and addresses.

 

@@ -861,17 +861,19 @@ GetScatterGatherHeadEntries (
   OUT EFI_PHYSICAL_ADDRESS **HeadList

   )

 {

-  EFI_STATUS                       Status;

-  UINTN                            Size;

-  UINTN                            Index;

-  UINTN                            TempIndex;

-  UINTN                            ValidIndex;

-  BOOLEAN                          Flag;

-  CHAR16                           CapsuleVarName[30];

-  CHAR16                           *TempVarName;

-  EFI_PHYSICAL_ADDRESS             CapsuleDataPtr64;

-  EFI_PEI_READ_ONLY_VARIABLE2_PPI  *PPIVariableServices;

-  EFI_PHYSICAL_ADDRESS             TempList[MAX_SG_LIST_HEADS];

+  EFI_STATUS                        Status;

+  UINTN                             Size;

+  UINTN                             Index;

+  UINTN                             TempIndex;

+  UINTN                             ValidIndex;

+  BOOLEAN                           Flag;

+  CHAR16                            CapsuleVarName[30];

+  CHAR16                            *TempVarName;

+  EFI_PHYSICAL_ADDRESS              CapsuleDataPtr64;

+  EFI_PEI_READ_ONLY_VARIABLE2_PPI   *PPIVariableServices;

+  EFI_PHYSICAL_ADDRESS              *TempList;

+  EFI_PHYSICAL_ADDRESS              *EnlargedTempList;

+  UINTN                             TempListLength;

 

   Index             = 0;

   TempVarName       = NULL;

@@ -902,11 +904,21 @@ GetScatterGatherHeadEntries (
   }

 

   //

+  // Allocate memory for sg list head

+  //

+  TempListLength = DEFAULT_SG_LIST_HEADS * sizeof (EFI_PHYSICAL_ADDRESS);

+  TempList = AllocateZeroPool (TempListLength);

+  if (TempList == NULL) {

+    DEBUG((DEBUG_ERROR, "Failed to allocate memory\n"));

+    return EFI_OUT_OF_RESOURCES;

+  }

+

+  //

   // setup var name buffer for update capsules

   //

   StrCpyS (CapsuleVarName, sizeof (CapsuleVarName) / sizeof (CHAR16), EFI_CAPSULE_VARIABLE_NAME);

   TempVarName = CapsuleVarName + StrLen (CapsuleVarName);

-  while (ValidIndex < MAX_SG_LIST_HEADS) {

+  while (TRUE) {

     if (Index != 0) {

       UnicodeValueToStringS (

         TempVarName,

@@ -949,6 +961,17 @@ GetScatterGatherHeadEntries (
     }

 

     //

+    // The TempList is full, enlarge it

+    //

+    if ((ValidIndex + 1) >= TempListLength) {

+      EnlargedTempList = AllocateZeroPool (TempListLength * 2);

+      CopyMem (EnlargedTempList, TempList, TempListLength);

+      FreePool (TempList);

+      TempList = EnlargedTempList;

+      TempListLength *= 2;

+    }

+

+    //

     // add it to the cached list

     //

     TempList[ValidIndex++] = CapsuleDataPtr64;