OvmfPkg/Library/LockBoxLib/LockBoxDxe.c

   1 /** @file
   2
   3   Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
   4
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include <Uefi.h>
  10
  11 #include <Library/MemoryAllocationLib.h>
  12 #include <Library/UefiBootServicesTableLib.h>
  13 #include <Library/BaseMemoryLib.h>
  14 #include <Library/DebugLib.h>
  15 #include <Protocol/LockBox.h>
  16 #include <LockBoxLib.h>
  17
  18 /**
  19   Allocate memory below 4G memory address.
  20
  21   This function allocates memory below 4G memory address.
  22
  23   @param  MemoryType   Memory type of memory to allocate.
  24   @param  Size         Size of memory to allocate.
  25
  26   @return Allocated address for output.
  27
  28 **/
  29 STATIC
  30 VOID *
  31 AllocateMemoryBelow4G (
  32   IN EFI_MEMORY_TYPE  MemoryType,
  33   IN UINTN            Size
  34   )
  35 {
  36   UINTN                 Pages;
  37   EFI_PHYSICAL_ADDRESS  Address;
  38   EFI_STATUS            Status;
  39   VOID                  *Buffer;
  40   UINTN                 AllocRemaining;
  41
  42   Pages   = EFI_SIZE_TO_PAGES (Size);
  43   Address = 0xffffffff;
  44
  45   //
  46   // Since we need to use gBS->AllocatePages to get a buffer below
  47   // 4GB, there is a good chance that space will be wasted for very
  48   // small allocation. We keep track of unused portions of the page
  49   // allocations, and use these to allocate memory for small buffers.
  50   //
  51   ASSERT (mLockBoxGlobal->Signature == LOCK_BOX_GLOBAL_SIGNATURE);
  52   if ((UINTN)mLockBoxGlobal->SubPageRemaining >= Size) {
  53     Buffer                            = (VOID *)(UINTN)mLockBoxGlobal->SubPageBuffer;
  54     mLockBoxGlobal->SubPageBuffer    += (UINT32)Size;
  55     mLockBoxGlobal->SubPageRemaining -= (UINT32)Size;
  56     return Buffer;
  57   }
  58
  59   Status = gBS->AllocatePages (
  60                   AllocateMaxAddress,
  61                   MemoryType,
  62                   Pages,
  63                   &Address
  64                   );
  65   if (EFI_ERROR (Status)) {
  66     return NULL;
  67   }
  68
  69   Buffer = (VOID *)(UINTN)Address;
  70   ZeroMem (Buffer, EFI_PAGES_TO_SIZE (Pages));
  71
  72   AllocRemaining = EFI_PAGES_TO_SIZE (Pages) - Size;
  73   if (AllocRemaining > (UINTN)mLockBoxGlobal->SubPageRemaining) {
  74     mLockBoxGlobal->SubPageBuffer    = (UINT32)(Address + Size);
  75     mLockBoxGlobal->SubPageRemaining = (UINT32)AllocRemaining;
  76   }
  77
  78   return Buffer;
  79 }
  80
  81 /**
  82   Allocates a buffer of type EfiACPIMemoryNVS.
  83
  84   Allocates the number bytes specified by AllocationSize of type
  85   EfiACPIMemoryNVS and returns a pointer to the allocated buffer.
  86   If AllocationSize is 0, then a valid buffer of 0 size is
  87   returned.  If there is not enough memory remaining to satisfy
  88   the request, then NULL is returned.
  89
  90   @param  AllocationSize        The number of bytes to allocate.
  91
  92   @return A pointer to the allocated buffer or NULL if allocation fails.
  93
  94 **/
  95 VOID *
  96 EFIAPI
  97 AllocateAcpiNvsPool (
  98   IN UINTN  AllocationSize
  99   )
 100 {
 101   return AllocateMemoryBelow4G (EfiACPIMemoryNVS, AllocationSize);
 102 }
 103
 104 EFI_STATUS
 105 EFIAPI
 106 LockBoxDxeLibInitialize (
 107   IN EFI_HANDLE        ImageHandle,
 108   IN EFI_SYSTEM_TABLE  *SystemTable
 109   )
 110 {
 111   EFI_STATUS  Status;
 112   VOID        *Interface;
 113
 114   Status = LockBoxLibInitialize ();
 115   if (!EFI_ERROR (Status)) {
 116     if (PcdGetBool (PcdAcpiS3Enable)) {
 117       //
 118       // When S3 enabled, the first driver run with this library linked will
 119       // have this library constructor to install LockBox protocol on the
 120       // ImageHandle. As other drivers may have gEfiLockBoxProtocolGuid
 121       // dependency, the first driver should run before them.
 122       //
 123       Status = gBS->LocateProtocol (&gEfiLockBoxProtocolGuid, NULL, &Interface);
 124       if (EFI_ERROR (Status)) {
 125         Status = gBS->InstallProtocolInterface (
 126                         &ImageHandle,
 127                         &gEfiLockBoxProtocolGuid,
 128                         EFI_NATIVE_INTERFACE,
 129                         NULL
 130                         );
 131         ASSERT_EFI_ERROR (Status);
 132       }
 133     }
 134   }
 135
 136   return Status;
 137 }