reactos/ntoskrnl/mm/i386/memsafe.s

   1 .globl _MmSafeCopyFromUser
   2 .globl _MmSafeCopyFromUserUnsafeStart
   3 .globl _MmSafeCopyFromUserRestart
   4 .globl _MmSafeCopyToUser
   5 .globl _MmSafeCopyToUserUnsafeStart
   6 .globl _MmSafeCopyToUserRestart
   7
   8         /*
   9          * NTSTATUS MmSafeCopyFromUser(PVOID Dest, PVOID Src,
  10          *                             ULONG NumberOfBytes)
  11          */
  12 _MmSafeCopyFromUser:
  13         pushl   %ebp
  14         movl    %esp,%ebp
  15
  16         pushl   %esi
  17         pushl   %edi
  18         pushl   %ecx
  19
  20         movl    8(%ebp),%edi
  21         movl    12(%ebp),%esi
  22         movl    16(%ebp),%ecx
  23
  24         /*
  25          * Default return code
  26          */
  27         movl    $0,%eax
  28
  29 _MmSafeCopyFromUserUnsafeStart:
  30         /*
  31          * This is really a synthetic instruction since if we incur a
  32          * pagefault then eax will be set to an appropiate STATUS code
  33          */
  34         rep movsb
  35
  36 _MmSafeCopyFromUserRestart:
  37
  38         popl    %ecx
  39         popl    %edi
  40         popl    %esi
  41
  42         popl    %ebp
  43         ret
  44
  45 /*****************************************************************************/
  46
  47         /*
  48          * NTSTATUS MmSafeCopyToUser(PVOID Dest, PVOID Src,
  49          *                      ULONG NumberOfBytes)
  50          */
  51 _MmSafeCopyToUser:
  52         pushl   %ebp
  53         movl    %esp,%ebp
  54
  55         pushl   %esi
  56         pushl   %edi
  57         pushl   %ecx
  58
  59         movl    8(%ebp),%edi
  60         movl    12(%ebp),%esi
  61         movl    16(%ebp),%ecx
  62
  63         /*
  64          * Default return code
  65          */
  66         movl    $0,%eax
  67
  68 _MmSafeCopyToUserUnsafeStart:
  69         /*
  70          * This is really a synthetic instruction since if we incur a
  71          * pagefault then eax will be set to an appropiate STATUS code
  72          */
  73         rep movsb
  74
  75 _MmSafeCopyToUserRestart:
  76
  77         popl    %ecx
  78         popl    %edi
  79         popl    %esi
  80
  81         popl    %ebp
  82         ret
  83