From bc012551321a42c14aa5cfb28ae946323d1aa381 Mon Sep 17 00:00:00 2001
From: Star Zeng <star.zeng@intel.com>
Date: Thu, 28 Aug 2014 06:02:43 +0000
Subject: [PATCH] MdeModulePkg DxeCore: Handle FFS file with
 FFS_ATTRIB_CHECKSUM set for not cache memory mapped IO FV.

The code FvCheck() will check FFS file checksum to verify if FFS file is valid when the file is
with FFS_ATTRIB_CHECKSUM set. The whole file will be read through when doing checksum check.
So we can cache FFS file to memory buffer for following checksum calculating first.
And then, the cached file buffer can be also used for FvReadFile.

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@15958 6f19259b-4bc3-4df7-8a09-765794883524
---
 MdeModulePkg/Core/Dxe/FwVol/FwVol.c | 55 +++++++++++++++++++++++------
 1 file changed, 45 insertions(+), 10 deletions(-)

diff --git a/MdeModulePkg/Core/Dxe/FwVol/FwVol.c b/MdeModulePkg/Core/Dxe/FwVol/FwVol.c
index d3447a57ac..4fa177ed7c 100644
--- a/MdeModulePkg/Core/Dxe/FwVol/FwVol.c
+++ b/MdeModulePkg/Core/Dxe/FwVol/FwVol.c
@@ -320,6 +320,12 @@ FvCheck (
   UINT8                                 *TopFvAddress;
   UINTN                                 TestLength;
   EFI_PHYSICAL_ADDRESS                  PhysicalAddress;
+  BOOLEAN                               FileCached;
+  UINTN                                 WholeFileSize;
+  EFI_FFS_FILE_HEADER                   *CacheFfsHeader;
+
+  FileCached = FALSE;
+  CacheFfsHeader = NULL;
 
   Fvb = FvDevice->Fvb;
   FwVolHeader = FvDevice->FwVolHeader;
@@ -460,6 +466,11 @@ FvCheck (
   TopFvAddress = FvDevice->EndOfCachedFv;
   while ((UINT8 *) FfsHeader < TopFvAddress) {
 
+    if (FileCached) {
+      CoreFreePool (CacheFfsHeader);
+      FileCached = FALSE;
+    }
+
     TestLength = TopFvAddress - ((UINT8 *) FfsHeader);
     if (TestLength > sizeof (EFI_FFS_FILE_HEADER)) {
       TestLength = sizeof (EFI_FFS_FILE_HEADER);
@@ -493,7 +504,25 @@ FvCheck (
       }
     }
 
-    if (!IsValidFfsFile (FvDevice->ErasePolarity, FfsHeader)) {
+    CacheFfsHeader = FfsHeader;
+    if ((CacheFfsHeader->Attributes & FFS_ATTRIB_CHECKSUM) == FFS_ATTRIB_CHECKSUM) {
+      if (FvDevice->IsMemoryMapped) {
+        //
+        // Memory mapped FV has not been cached.
+        // Here is to cache FFS file to memory buffer for following checksum calculating.
+        // And then, the cached file buffer can be also used for FvReadFile.
+        //
+        WholeFileSize = IS_FFS_FILE2 (CacheFfsHeader) ? FFS_FILE2_SIZE (CacheFfsHeader): FFS_FILE_SIZE (CacheFfsHeader);
+        CacheFfsHeader = AllocateCopyPool (WholeFileSize, CacheFfsHeader);
+        if (CacheFfsHeader == NULL) {
+          Status = EFI_OUT_OF_RESOURCES;
+          goto Done;
+        }
+        FileCached = TRUE;
+      }
+    }
+
+    if (!IsValidFfsFile (FvDevice->ErasePolarity, CacheFfsHeader)) {
       //
       // File system is corrupted
       //
@@ -501,11 +530,11 @@ FvCheck (
       goto Done;
     }
 
-    if (IS_FFS_FILE2 (FfsHeader)) {
-      ASSERT (FFS_FILE2_SIZE (FfsHeader) > 0x00FFFFFF);
+    if (IS_FFS_FILE2 (CacheFfsHeader)) {
+      ASSERT (FFS_FILE2_SIZE (CacheFfsHeader) > 0x00FFFFFF);
       if (!FvDevice->IsFfs3Fv) {
-        DEBUG ((EFI_D_ERROR, "Found a FFS3 formatted file: %g in a non-FFS3 formatted FV.\n", &FfsHeader->Name));
-        FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE2_SIZE (FfsHeader));
+        DEBUG ((EFI_D_ERROR, "Found a FFS3 formatted file: %g in a non-FFS3 formatted FV.\n", &CacheFfsHeader->Name));
+        FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE2_SIZE (CacheFfsHeader));
         //
         // Adjust pointer to the next 8-byte aligned boundry.
         //
@@ -514,7 +543,7 @@ FvCheck (
       }
     }
 
-    FileState = GetFileState (FvDevice->ErasePolarity, FfsHeader);
+    FileState = GetFileState (FvDevice->ErasePolarity, CacheFfsHeader);
 
     //
     // check for non-deleted file
@@ -529,14 +558,16 @@ FvCheck (
         goto Done;
       }
 
-      FfsFileEntry->FfsHeader = FfsHeader;
+      FfsFileEntry->FfsHeader = CacheFfsHeader;
+      FfsFileEntry->FileCached = FileCached;
+      FileCached = FALSE;
       InsertTailList (&FvDevice->FfsFileListHeader, &FfsFileEntry->Link);
     }
 
-    if (IS_FFS_FILE2 (FfsHeader)) {
-      FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE2_SIZE (FfsHeader));
+    if (IS_FFS_FILE2 (CacheFfsHeader)) {
+      FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE2_SIZE (CacheFfsHeader));
     } else {
-      FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE_SIZE (FfsHeader));
+      FfsHeader = (EFI_FFS_FILE_HEADER *) ((UINT8 *) FfsHeader + FFS_FILE_SIZE (CacheFfsHeader));
     }
 
     //
@@ -548,6 +579,10 @@ FvCheck (
 
 Done:
   if (EFI_ERROR (Status)) {
+    if (FileCached) {
+      CoreFreePool (CacheFfsHeader);
+      FileCached = FALSE;
+    }
     FreeFvDeviceResource (FvDevice);
   }
 
-- 
2.39.2