OvmfPkg/Library/LockBoxLib/LockBoxDxe.c

   1 /** @file
   2
   3   Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
   4
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php.
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include <Uefi.h>
  16
  17 #include <Library/MemoryAllocationLib.h>
  18 #include <Library/UefiBootServicesTableLib.h>
  19 #include <Library/BaseMemoryLib.h>
  20 #include <Library/DebugLib.h>
  21 #include <Library/QemuFwCfgLib.h>
  22 #include <Protocol/LockBox.h>
  23 #include <LockBoxLib.h>
  24
  25 /**
  26   Allocate memory below 4G memory address.
  27
  28   This function allocates memory below 4G memory address.
  29
  30   @param  MemoryType   Memory type of memory to allocate.
  31   @param  Size         Size of memory to allocate.
  32
  33   @return Allocated address for output.
  34
  35 **/
  36 STATIC
  37 VOID *
  38 AllocateMemoryBelow4G (
  39   IN EFI_MEMORY_TYPE    MemoryType,
  40   IN UINTN              Size
  41   )
  42 {
  43   UINTN                 Pages;
  44   EFI_PHYSICAL_ADDRESS  Address;
  45   EFI_STATUS            Status;
  46   VOID*                 Buffer;
  47   UINTN                 AllocRemaining;
  48
  49   Pages = EFI_SIZE_TO_PAGES (Size);
  50   Address = 0xffffffff;
  51
  52   //
  53   // Since we need to use gBS->AllocatePages to get a buffer below
  54   // 4GB, there is a good chance that space will be wasted for very
  55   // small allocation. We keep track of unused portions of the page
  56   // allocations, and use these to allocate memory for small buffers.
  57   //
  58   ASSERT (mLockBoxGlobal->Signature == LOCK_BOX_GLOBAL_SIGNATURE);
  59   if ((UINTN) mLockBoxGlobal->SubPageRemaining >= Size) {
  60     Buffer = (VOID*)(UINTN) mLockBoxGlobal->SubPageBuffer;
  61     mLockBoxGlobal->SubPageBuffer += (UINT32) Size;
  62     mLockBoxGlobal->SubPageRemaining -= (UINT32) Size;
  63     return Buffer;
  64   }
  65
  66   Status  = gBS->AllocatePages (
  67                    AllocateMaxAddress,
  68                    MemoryType,
  69                    Pages,
  70                    &Address
  71                    );
  72   if (EFI_ERROR (Status)) {
  73     return NULL;
  74   }
  75
  76   Buffer = (VOID *) (UINTN) Address;
  77   ZeroMem (Buffer, EFI_PAGES_TO_SIZE (Pages));
  78
  79   AllocRemaining = EFI_PAGES_TO_SIZE (Pages) - Size;
  80   if (AllocRemaining > (UINTN) mLockBoxGlobal->SubPageRemaining) {
  81     mLockBoxGlobal->SubPageBuffer = (UINT32) (Address + Size);
  82     mLockBoxGlobal->SubPageRemaining = (UINT32) AllocRemaining;
  83   }
  84
  85   return Buffer;
  86 }
  87
  88
  89 /**
  90   Allocates a buffer of type EfiACPIMemoryNVS.
  91
  92   Allocates the number bytes specified by AllocationSize of type
  93   EfiACPIMemoryNVS and returns a pointer to the allocated buffer.
  94   If AllocationSize is 0, then a valid buffer of 0 size is
  95   returned.  If there is not enough memory remaining to satisfy
  96   the request, then NULL is returned.
  97
  98   @param  AllocationSize        The number of bytes to allocate.
  99
 100   @return A pointer to the allocated buffer or NULL if allocation fails.
 101
 102 **/
 103 VOID *
 104 EFIAPI
 105 AllocateAcpiNvsPool (
 106   IN UINTN  AllocationSize
 107   )
 108 {
 109   return AllocateMemoryBelow4G (EfiACPIMemoryNVS, AllocationSize);
 110 }
 111
 112
 113 EFI_STATUS
 114 EFIAPI
 115 LockBoxDxeLibInitialize (
 116   IN EFI_HANDLE        ImageHandle,
 117   IN EFI_SYSTEM_TABLE  *SystemTable
 118   )
 119 {
 120   EFI_STATUS    Status;
 121   VOID          *Interface;
 122
 123   Status = LockBoxLibInitialize ();
 124   if (!EFI_ERROR (Status)) {
 125     if (QemuFwCfgS3Enabled ()) {
 126       //
 127       // When S3 enabled, the first driver run with this library linked will
 128       // have this library constructor to install LockBox protocol on the
 129       // ImageHandle. As other drivers may have gEfiLockBoxProtocolGuid
 130       // dependency, the first driver should run before them.
 131       //
 132       Status = gBS->LocateProtocol (&gEfiLockBoxProtocolGuid, NULL, &Interface);
 133       if (EFI_ERROR (Status)) {
 134         Status = gBS->InstallProtocolInterface (
 135                         &ImageHandle,
 136                         &gEfiLockBoxProtocolGuid,
 137                         EFI_NATIVE_INTERFACE,
 138                         NULL
 139                         );
 140         ASSERT_EFI_ERROR (Status);
 141       }
 142     }
 143   }
 144
 145   return Status;
 146 }