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 /**
  83   Allocates a buffer of type EfiACPIMemoryNVS.
  84
  85   Allocates the number bytes specified by AllocationSize of type
  86   EfiACPIMemoryNVS and returns a pointer to the allocated buffer.
  87   If AllocationSize is 0, then a valid buffer of 0 size is
  88   returned.  If there is not enough memory remaining to satisfy
  89   the request, then NULL is returned.
  90
  91   @param  AllocationSize        The number of bytes to allocate.
  92
  93   @return A pointer to the allocated buffer or NULL if allocation fails.
  94
  95 **/
  96 VOID *
  97 EFIAPI
  98 AllocateAcpiNvsPool (
  99   IN UINTN  AllocationSize
 100   )
 101 {
 102   return AllocateMemoryBelow4G (EfiACPIMemoryNVS, AllocationSize);
 103 }
 104
 105
 106 EFI_STATUS
 107 EFIAPI
 108 LockBoxDxeLibInitialize (
 109   IN EFI_HANDLE        ImageHandle,
 110   IN EFI_SYSTEM_TABLE  *SystemTable
 111   )
 112 {
 113   EFI_STATUS    Status;
 114   VOID          *Interface;
 115
 116   Status = LockBoxLibInitialize ();
 117   if (!EFI_ERROR (Status)) {
 118     if (PcdGetBool (PcdAcpiS3Enable)) {
 119       //
 120       // When S3 enabled, the first driver run with this library linked will
 121       // have this library constructor to install LockBox protocol on the
 122       // ImageHandle. As other drivers may have gEfiLockBoxProtocolGuid
 123       // dependency, the first driver should run before them.
 124       //
 125       Status = gBS->LocateProtocol (&gEfiLockBoxProtocolGuid, NULL, &Interface);
 126       if (EFI_ERROR (Status)) {
 127         Status = gBS->InstallProtocolInterface (
 128                         &ImageHandle,
 129                         &gEfiLockBoxProtocolGuid,
 130                         EFI_NATIVE_INTERFACE,
 131                         NULL
 132                         );
 133         ASSERT_EFI_ERROR (Status);
 134       }
 135     }
 136   }
 137
 138   return Status;
 139 }