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 <Library/QemuFwCfgLib.h>
  16 #include <Library/QemuFwCfgS3Lib.h>
  17 #include <Protocol/LockBox.h>
  18 #include <LockBoxLib.h>
  19
  20 /**
  21   Allocate memory below 4G memory address.
  22
  23   This function allocates memory below 4G memory address.
  24
  25   @param  MemoryType   Memory type of memory to allocate.
  26   @param  Size         Size of memory to allocate.
  27
  28   @return Allocated address for output.
  29
  30 **/
  31 STATIC
  32 VOID *
  33 AllocateMemoryBelow4G (
  34   IN EFI_MEMORY_TYPE    MemoryType,
  35   IN UINTN              Size
  36   )
  37 {
  38   UINTN                 Pages;
  39   EFI_PHYSICAL_ADDRESS  Address;
  40   EFI_STATUS            Status;
  41   VOID*                 Buffer;
  42   UINTN                 AllocRemaining;
  43
  44   Pages = EFI_SIZE_TO_PAGES (Size);
  45   Address = 0xffffffff;
  46
  47   //
  48   // Since we need to use gBS->AllocatePages to get a buffer below
  49   // 4GB, there is a good chance that space will be wasted for very
  50   // small allocation. We keep track of unused portions of the page
  51   // allocations, and use these to allocate memory for small buffers.
  52   //
  53   ASSERT (mLockBoxGlobal->Signature == LOCK_BOX_GLOBAL_SIGNATURE);
  54   if ((UINTN) mLockBoxGlobal->SubPageRemaining >= Size) {
  55     Buffer = (VOID*)(UINTN) mLockBoxGlobal->SubPageBuffer;
  56     mLockBoxGlobal->SubPageBuffer += (UINT32) Size;
  57     mLockBoxGlobal->SubPageRemaining -= (UINT32) Size;
  58     return Buffer;
  59   }
  60
  61   Status  = gBS->AllocatePages (
  62                    AllocateMaxAddress,
  63                    MemoryType,
  64                    Pages,
  65                    &Address
  66                    );
  67   if (EFI_ERROR (Status)) {
  68     return NULL;
  69   }
  70
  71   Buffer = (VOID *) (UINTN) Address;
  72   ZeroMem (Buffer, EFI_PAGES_TO_SIZE (Pages));
  73
  74   AllocRemaining = EFI_PAGES_TO_SIZE (Pages) - Size;
  75   if (AllocRemaining > (UINTN) mLockBoxGlobal->SubPageRemaining) {
  76     mLockBoxGlobal->SubPageBuffer = (UINT32) (Address + Size);
  77     mLockBoxGlobal->SubPageRemaining = (UINT32) AllocRemaining;
  78   }
  79
  80   return Buffer;
  81 }
  82
  83
  84 /**
  85   Allocates a buffer of type EfiACPIMemoryNVS.
  86
  87   Allocates the number bytes specified by AllocationSize of type
  88   EfiACPIMemoryNVS and returns a pointer to the allocated buffer.
  89   If AllocationSize is 0, then a valid buffer of 0 size is
  90   returned.  If there is not enough memory remaining to satisfy
  91   the request, then NULL is returned.
  92
  93   @param  AllocationSize        The number of bytes to allocate.
  94
  95   @return A pointer to the allocated buffer or NULL if allocation fails.
  96
  97 **/
  98 VOID *
  99 EFIAPI
 100 AllocateAcpiNvsPool (
 101   IN UINTN  AllocationSize
 102   )
 103 {
 104   return AllocateMemoryBelow4G (EfiACPIMemoryNVS, AllocationSize);
 105 }
 106
 107
 108 EFI_STATUS
 109 EFIAPI
 110 LockBoxDxeLibInitialize (
 111   IN EFI_HANDLE        ImageHandle,
 112   IN EFI_SYSTEM_TABLE  *SystemTable
 113   )
 114 {
 115   EFI_STATUS    Status;
 116   VOID          *Interface;
 117
 118   Status = LockBoxLibInitialize ();
 119   if (!EFI_ERROR (Status)) {
 120     if (QemuFwCfgS3Enabled ()) {
 121       //
 122       // When S3 enabled, the first driver run with this library linked will
 123       // have this library constructor to install LockBox protocol on the
 124       // ImageHandle. As other drivers may have gEfiLockBoxProtocolGuid
 125       // dependency, the first driver should run before them.
 126       //
 127       Status = gBS->LocateProtocol (&gEfiLockBoxProtocolGuid, NULL, &Interface);
 128       if (EFI_ERROR (Status)) {
 129         Status = gBS->InstallProtocolInterface (
 130                         &ImageHandle,
 131                         &gEfiLockBoxProtocolGuid,
 132                         EFI_NATIVE_INTERFACE,
 133                         NULL
 134                         );
 135         ASSERT_EFI_ERROR (Status);
 136       }
 137     }
 138   }
 139
 140   return Status;
 141 }