rosapps/applications/sysutils/utils/pice/module/dblflt.c

   1 /*++
   2
   3 Copyright (c) 1998-2001 Klaus P. Gerlicher
   4
   5 Module Name:
   6
   7     dblflt.c
   8
   9 Abstract:
  10
  11     handle double faults on x86
  12
  13 Environment:
  14
  15     LINUX 2.2.X
  16     Kernel mode only
  17
  18 Author:
  19
  20     Klaus P. Gerlicher
  21
  22 Revision History:
  23
  24     13-Nov-1999:        created
  25     15-Nov-2000:    general cleanup of source files
  26
  27 Copyright notice:
  28
  29   This file may be distributed under the terms of the GNU Public License.
  30
  31 --*/
  32
  33 ////////////////////////////////////////////////////
  34 // INCLUDES
  35 ////
  36 #include "remods.h"
  37 #include "precomp.h"
  38
  39 ////////////////////////////////////////////////////
  40 // GLOBALS
  41 ////
  42 ULONG OldDblFltHandler = 0;
  43
  44 ////////////////////////////////////////////////////
  45 // FUNCTIONS
  46 ////
  47
  48 //*************************************************************************
  49 // HandleDoubleFault()
  50 //
  51 //*************************************************************************
  52 void HandleDoubleFault(FRAME* ptr)
  53 {
  54     DPRINT((0,"HandleDoubleFault(): ptr = %x\n",ptr));
  55 }
  56
  57
  58 //*************************************************************************
  59 // NewDblFltHandler()
  60 //
  61 //*************************************************************************
  62 __asm__ (" \
  63 NewDblFltHandler:\n\t \
  64                 pushfl\n\t \
  65         cli;\n\t \
  66         cld;\n\t \
  67         pushal;\n\t \
  68             pushl %ds;\n\t \
  69 \n\t \
  70             // setup default data selectors\n\t \
  71             movw %ss,%ax\n\t \
  72             movw %ax,%ds\n\t \
  73 \n\t \
  74         // get frame ptr\n\t \
  75         lea 40(%esp),%eax\n\t \
  76         pushl %eax\n\t \
  77         call _HandleDoubleFault\n\t \
  78         addl $4,%esp\n\t \
  79 \n\t \
  80             popl %ds\n\t \
  81         popal\n\t \
  82                 popfl\n\t \
  83                 // remove error code from stack and replace with reason code\n\t \
  84         movl $" STR(REASON_DOUBLE_FAULT) ",(%esp)\n\t \
  85                 // call debugger loop\n\t \
  86                 jmp NewInt31Handler\n\t");
  87
  88
  89 //*************************************************************************
  90 // InstallDblFltHook()
  91 //
  92 //*************************************************************************
  93 void InstallDblFltHook(void)
  94 {
  95         ULONG LocalDblFltHandler;
  96
  97         ENTER_FUNC();
  98
  99         MaskIrqs();
 100         if(!OldDblFltHandler)
 101         {
 102                 __asm__("mov $NewDblFltHandler,%0"
 103                         :"=r" (LocalDblFltHandler)
 104                         :
 105                         :"eax");
 106                 OldDblFltHandler=SetGlobalInt(0x08,(ULONG)LocalDblFltHandler);
 107         }
 108         UnmaskIrqs();
 109
 110     LEAVE_FUNC();
 111 }
 112
 113 //*************************************************************************
 114 // DeInstallDblFltHook()
 115 //
 116 //*************************************************************************
 117 void DeInstallDblFltHook(void)
 118 {
 119         ENTER_FUNC();
 120
 121         MaskIrqs();
 122         if(OldDblFltHandler)
 123         {
 124         RemoveAllSWBreakpoints(TRUE);
 125                 SetGlobalInt(0x08,(ULONG)OldDblFltHandler);
 126         OldDblFltHandler=0;
 127         }
 128         UnmaskIrqs();
 129
 130     LEAVE_FUNC();
 131 }
 132
 133 // EOF