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 <Library/QemuFwCfgS3Lib.h>
  23 #include <Protocol/LockBox.h>
  24 #include <LockBoxLib.h>
  25
  26 /**
  27   Allocate memory below 4G memory address.
  28
  29   This function allocates memory below 4G memory address.
  30
  31   @param  MemoryType   Memory type of memory to allocate.
  32   @param  Size         Size of memory to allocate.
  33
  34   @return Allocated address for output.
  35
  36 **/
  37 STATIC
  38 VOID *
  39 AllocateMemoryBelow4G (
  40   IN EFI_MEMORY_TYPE    MemoryType,
  41   IN UINTN              Size
  42   )
  43 {
  44   UINTN                 Pages;
  45   EFI_PHYSICAL_ADDRESS  Address;
  46   EFI_STATUS            Status;
  47   VOID*                 Buffer;
  48   UINTN                 AllocRemaining;
  49
  50   Pages = EFI_SIZE_TO_PAGES (Size);
  51   Address = 0xffffffff;
  52
  53   //
  54   // Since we need to use gBS->AllocatePages to get a buffer below
  55   // 4GB, there is a good chance that space will be wasted for very
  56   // small allocation. We keep track of unused portions of the page
  57   // allocations, and use these to allocate memory for small buffers.
  58   //
  59   ASSERT (mLockBoxGlobal->Signature == LOCK_BOX_GLOBAL_SIGNATURE);
  60   if ((UINTN) mLockBoxGlobal->SubPageRemaining >= Size) {
  61     Buffer = (VOID*)(UINTN) mLockBoxGlobal->SubPageBuffer;
  62     mLockBoxGlobal->SubPageBuffer += (UINT32) Size;
  63     mLockBoxGlobal->SubPageRemaining -= (UINT32) Size;
  64     return Buffer;
  65   }
  66
  67   Status  = gBS->AllocatePages (
  68                    AllocateMaxAddress,
  69                    MemoryType,
  70                    Pages,
  71                    &Address
  72                    );
  73   if (EFI_ERROR (Status)) {
  74     return NULL;
  75   }
  76
  77   Buffer = (VOID *) (UINTN) Address;
  78   ZeroMem (Buffer, EFI_PAGES_TO_SIZE (Pages));
  79
  80   AllocRemaining = EFI_PAGES_TO_SIZE (Pages) - Size;
  81   if (AllocRemaining > (UINTN) mLockBoxGlobal->SubPageRemaining) {
  82     mLockBoxGlobal->SubPageBuffer = (UINT32) (Address + Size);
  83     mLockBoxGlobal->SubPageRemaining = (UINT32) AllocRemaining;
  84   }
  85
  86   return Buffer;
  87 }
  88
  89
  90 /**
  91   Allocates a buffer of type EfiACPIMemoryNVS.
  92
  93   Allocates the number bytes specified by AllocationSize of type
  94   EfiACPIMemoryNVS and returns a pointer to the allocated buffer.
  95   If AllocationSize is 0, then a valid buffer of 0 size is
  96   returned.  If there is not enough memory remaining to satisfy
  97   the request, then NULL is returned.
  98
  99   @param  AllocationSize        The number of bytes to allocate.
 100
 101   @return A pointer to the allocated buffer or NULL if allocation fails.
 102
 103 **/
 104 VOID *
 105 EFIAPI
 106 AllocateAcpiNvsPool (
 107   IN UINTN  AllocationSize
 108   )
 109 {
 110   return AllocateMemoryBelow4G (EfiACPIMemoryNVS, AllocationSize);
 111 }
 112
 113
 114 EFI_STATUS
 115 EFIAPI
 116 LockBoxDxeLibInitialize (
 117   IN EFI_HANDLE        ImageHandle,
 118   IN EFI_SYSTEM_TABLE  *SystemTable
 119   )
 120 {
 121   EFI_STATUS    Status;
 122   VOID          *Interface;
 123
 124   Status = LockBoxLibInitialize ();
 125   if (!EFI_ERROR (Status)) {
 126     if (QemuFwCfgS3Enabled ()) {
 127       //
 128       // When S3 enabled, the first driver run with this library linked will
 129       // have this library constructor to install LockBox protocol on the
 130       // ImageHandle. As other drivers may have gEfiLockBoxProtocolGuid
 131       // dependency, the first driver should run before them.
 132       //
 133       Status = gBS->LocateProtocol (&gEfiLockBoxProtocolGuid, NULL, &Interface);
 134       if (EFI_ERROR (Status)) {
 135         Status = gBS->InstallProtocolInterface (
 136                         &ImageHandle,
 137                         &gEfiLockBoxProtocolGuid,
 138                         EFI_NATIVE_INTERFACE,
 139                         NULL
 140                         );
 141         ASSERT_EFI_ERROR (Status);
 142       }
 143     }
 144   }
 145
 146   return Status;
 147 }