cpu/io_pro.cc

   1 /////////////////////////////////////////////////////////////////////////
   2 // $Id: io_pro.cc,v 1.39 2008/09/14 20:58:20 sshwarts Exp $
   3 /////////////////////////////////////////////////////////////////////////
   4 //
   5 //  Copyright (C) 2001  MandrakeSoft S.A.
   6 //
   7 //    MandrakeSoft S.A.
   8 //    43, rue d'Aboukir
   9 //    75002 Paris - France
  10 //    http://www.linux-mandrake.com/
  11 //    http://www.mandrakesoft.com/
  12 //
  13 //  This library is free software; you can redistribute it and/or
  14 //  modify it under the terms of the GNU Lesser General Public
  15 //  License as published by the Free Software Foundation; either
  16 //  version 2 of the License, or (at your option) any later version.
  17 //
  18 //  This library is distributed in the hope that it will be useful,
  19 //  but WITHOUT ANY WARRANTY; without even the implied warranty of
  20 //  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  21 //  Lesser General Public License for more details.
  22 //
  23 //  You should have received a copy of the GNU Lesser General Public
  24 //  License along with this library; if not, write to the Free Software
  25 //  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  26 //
  27 /////////////////////////////////////////////////////////////////////////
  28
  29 #define NEED_CPU_REG_SHORTCUTS 1
  30 #include "bochs.h"
  31 #include "cpu.h"
  32 #define LOG_THIS BX_CPU_THIS_PTR
  33
  34 #include "iodev/iodev.h"
  35
  36   Bit16u BX_CPP_AttrRegparmN(1)
  37 BX_CPU_C::inp16(Bit16u port)
  38 {
  39   if (! BX_CPU_THIS_PTR allow_io(port, 2)) {
  40     BX_DEBUG(("inp16(): I/O access not allowed !"));
  41     exception(BX_GP_EXCEPTION, 0, 0);
  42   }
  43
  44   Bit16u ret16 = BX_INP(port, 2);
  45   return ret16;
  46 }
  47
  48   void BX_CPP_AttrRegparmN(2)
  49 BX_CPU_C::outp16(Bit16u port, Bit16u value)
  50 {
  51   if (! BX_CPU_THIS_PTR allow_io(port, 2)) {
  52     BX_DEBUG(("outp16(): I/O access not allowed !"));
  53     exception(BX_GP_EXCEPTION, 0, 0);
  54   }
  55
  56   BX_OUTP(port, value, 2);
  57 }
  58
  59   Bit32u BX_CPP_AttrRegparmN(1)
  60 BX_CPU_C::inp32(Bit16u port)
  61 {
  62   if (! BX_CPU_THIS_PTR allow_io(port, 4)) {
  63     BX_DEBUG(("inp32(): I/O access not allowed !"));
  64     exception(BX_GP_EXCEPTION, 0, 0);
  65   }
  66
  67   Bit32u ret32 = BX_INP(port, 4);
  68   return ret32;
  69 }
  70
  71   void BX_CPP_AttrRegparmN(2)
  72 BX_CPU_C::outp32(Bit16u port, Bit32u value)
  73 {
  74   if (! BX_CPU_THIS_PTR allow_io(port, 4)) {
  75     BX_DEBUG(("outp32(): I/O access not allowed !"));
  76     exception(BX_GP_EXCEPTION, 0, 0);
  77   }
  78
  79   BX_OUTP(port, value, 4);
  80 }
  81
  82   Bit8u BX_CPP_AttrRegparmN(1)
  83 BX_CPU_C::inp8(Bit16u port)
  84 {
  85   if (! BX_CPU_THIS_PTR allow_io(port, 1)) {
  86     BX_DEBUG(("inp8(): I/O access not allowed !"));
  87     exception(BX_GP_EXCEPTION, 0, 0);
  88   }
  89
  90   Bit8u ret8 = BX_INP(port, 1);
  91   return ret8;
  92 }
  93
  94   void BX_CPP_AttrRegparmN(2)
  95 BX_CPU_C::outp8(Bit16u port, Bit8u value)
  96 {
  97   if (! BX_CPU_THIS_PTR allow_io(port, 1)) {
  98     BX_DEBUG(("outp8(): I/O access not allowed !"));
  99     exception(BX_GP_EXCEPTION, 0, 0);
 100   }
 101
 102   BX_OUTP(port, value, 1);
 103 }
 104
 105 bx_bool BX_CPU_C::allow_io(Bit16u port, unsigned len)
 106 {
 107   /* If CPL <= IOPL, then all IO portesses are accessible.
 108    * Otherwise, must check the IO permission map on >286.
 109    * On the 286, there is no IO permissions map */
 110
 111   if (BX_CPU_THIS_PTR cr0.get_PE() && (BX_CPU_THIS_PTR get_VM() || (CPL>BX_CPU_THIS_PTR get_IOPL())))
 112   {
 113     if (BX_CPU_THIS_PTR tr.cache.valid==0 ||
 114        (BX_CPU_THIS_PTR tr.cache.type != BX_SYS_SEGMENT_AVAIL_386_TSS &&
 115         BX_CPU_THIS_PTR tr.cache.type != BX_SYS_SEGMENT_BUSY_386_TSS))
 116     {
 117       BX_ERROR(("allow_io(): TR doesn't point to a valid 32bit TSS, TR.TYPE=%u", BX_CPU_THIS_PTR tr.cache.type));
 118       return(0);
 119     }
 120
 121     if (BX_CPU_THIS_PTR tr.cache.u.system.limit_scaled < 103) {
 122       BX_ERROR(("allow_io(): TR.limit < 103"));
 123       return(0);
 124     }
 125
 126     Bit16u io_base = system_read_word(BX_CPU_THIS_PTR tr.cache.u.system.base + 102);
 127
 128     if ((io_base + port/8) >= BX_CPU_THIS_PTR tr.cache.u.system.limit_scaled) {
 129       BX_DEBUG(("allow_io(): IO port %x (len %d) outside TSS IO permission map (base=%x, limit=%x) #GP(0)",
 130         port, len, io_base, BX_CPU_THIS_PTR tr.cache.u.system.limit_scaled));
 131       return(0);
 132     }
 133
 134     Bit16u permission16 = system_read_word(BX_CPU_THIS_PTR tr.cache.u.system.base + io_base + port/8);
 135
 136     unsigned bit_index = port & 0x7;
 137     unsigned mask = (1 << len) - 1;
 138     if ((permission16 >> bit_index) & mask)
 139       return(0);
 140   }
 141
 142 #if BX_X86_DEBUGGER
 143   iobreakpoint_match(port, len);
 144 #endif
 145
 146   return(1);
 147 }