Bochs/bochs/cpu/access.cc

320 lines
10 KiB
C++

/////////////////////////////////////////////////////////////////////////
// $Id: access.cc,v 1.118 2008-08-14 22:26:14 sshwarts Exp $
/////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2001 MandrakeSoft S.A.
//
// MandrakeSoft S.A.
// 43, rue d'Aboukir
// 75002 Paris - France
// http://www.linux-mandrake.com/
// http://www.mandrakesoft.com/
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
//
/////////////////////////////////////////////////////////////////////////
#define NEED_CPU_REG_SHORTCUTS 1
#include "bochs.h"
#include "cpu.h"
#define LOG_THIS BX_CPU_THIS_PTR
bx_bool BX_CPP_AttrRegparmN(3)
BX_CPU_C::write_virtual_checks(bx_segment_reg_t *seg, Bit32u offset, unsigned length)
{
Bit32u upper_limit;
#if BX_SUPPORT_X86_64
if (BX_CPU_THIS_PTR cpu_mode == BX_MODE_LONG_64) {
// Mark cache as being OK type for succeeding reads/writes
seg->cache.valid |= SegAccessROK | SegAccessWOK | SegAccessROK4G | SegAccessWOK4G;
return 1;
}
#endif
if (seg->cache.valid==0) {
BX_DEBUG(("write_virtual_checks(): segment descriptor not valid"));
return 0;
}
if (seg->cache.p == 0) { /* not present */
BX_ERROR(("write_virtual_checks(): segment not present"));
return 0;
}
switch (seg->cache.type) {
case 0: case 1: // read only
case 4: case 5: // read only, expand down
case 8: case 9: // execute only
case 10: case 11: // execute/read
case 12: case 13: // execute only, conforming
case 14: case 15: // execute/read-only, conforming
BX_ERROR(("write_virtual_checks(): no write access to seg"));
return 0;
case 2: case 3: /* read/write */
if (offset > (seg->cache.u.segment.limit_scaled - length + 1)
|| (length-1 > seg->cache.u.segment.limit_scaled))
{
BX_ERROR(("write_virtual_checks(): write beyond limit, r/w"));
return 0;
}
if (seg->cache.u.segment.limit_scaled >= 15) {
// Mark cache as being OK type for succeeding read/writes. The limit
// checks still needs to be done though, but is more simple. We
// could probably also optimize that out with a flag for the case
// when limit is the maximum 32bit value. Limit should accomodate
// at least a dword, since we subtract from it in the simple
// limit check in other functions, and we don't want the value to roll.
// Only normal segments (not expand down) are handled this way.
seg->cache.valid |= SegAccessROK | SegAccessWOK;
if (seg->cache.u.segment.limit_scaled == 0xffffffff)
seg->cache.valid |= SegAccessROK4G | SegAccessWOK4G;
}
break;
case 6: case 7: /* read/write, expand down */
if (seg->cache.u.segment.d_b)
upper_limit = 0xffffffff;
else
upper_limit = 0x0000ffff;
if ((offset <= seg->cache.u.segment.limit_scaled) ||
(offset > upper_limit) || ((upper_limit - offset) < (length - 1)))
{
BX_ERROR(("write_virtual_checks(): write beyond limit, r/w ED"));
return 0;
}
break;
default:
BX_PANIC(("write_virtual_checks(): unknown descriptor type=%d", seg->cache.type));
}
return 1;
}
bx_bool BX_CPP_AttrRegparmN(3)
BX_CPU_C::read_virtual_checks(bx_segment_reg_t *seg, Bit32u offset, unsigned length)
{
Bit32u upper_limit;
#if BX_SUPPORT_X86_64
if (BX_CPU_THIS_PTR cpu_mode == BX_MODE_LONG_64) {
// Mark cache as being OK type for succeeding reads/writes
seg->cache.valid |= SegAccessROK | SegAccessWOK | SegAccessROK4G | SegAccessWOK4G;
return 1;
}
#endif
if (seg->cache.valid==0) {
BX_DEBUG(("read_virtual_checks(): segment descriptor not valid"));
return 0;
}
if (seg->cache.p == 0) { /* not present */
BX_ERROR(("read_virtual_checks(): segment not present"));
return 0;
}
switch (seg->cache.type) {
case 0: case 1: /* read only */
case 2: case 3: /* read/write */
case 10: case 11: /* execute/read */
case 14: case 15: /* execute/read-only, conforming */
if (offset > (seg->cache.u.segment.limit_scaled - length + 1)
|| (length-1 > seg->cache.u.segment.limit_scaled))
{
BX_ERROR(("read_virtual_checks(): read beyond limit"));
return 0;
}
if (seg->cache.u.segment.limit_scaled >= 15) {
// Mark cache as being OK type for succeeding reads. See notes for
// write checks; similar code.
seg->cache.valid |= SegAccessROK;
if (seg->cache.u.segment.limit_scaled == 0xffffffff)
seg->cache.valid |= SegAccessROK4G;
}
break;
case 4: case 5: /* read only, expand down */
case 6: case 7: /* read/write, expand down */
if (seg->cache.u.segment.d_b)
upper_limit = 0xffffffff;
else
upper_limit = 0x0000ffff;
if ((offset <= seg->cache.u.segment.limit_scaled) ||
(offset > upper_limit) || ((upper_limit - offset) < (length - 1)))
{
BX_ERROR(("read_virtual_checks(): read beyond limit ED"));
return 0;
}
break;
case 8: case 9: /* execute only */
case 12: case 13: /* execute only, conforming */
/* can't read or write an execute-only segment */
BX_ERROR(("read_virtual_checks(): execute only"));
return 0;
default:
BX_PANIC(("read_virtual_checks(): unknown descriptor type=%d", seg->cache.type));
}
return 1;
}
bx_bool BX_CPP_AttrRegparmN(3)
BX_CPU_C::execute_virtual_checks(bx_segment_reg_t *seg, Bit32u offset, unsigned length)
{
Bit32u upper_limit;
#if BX_SUPPORT_X86_64
if (BX_CPU_THIS_PTR cpu_mode == BX_MODE_LONG_64) {
// Mark cache as being OK type for succeeding reads/writes
seg->cache.valid |= SegAccessROK | SegAccessWOK | SegAccessROK4G | SegAccessWOK4G;
return 1;
}
#endif
if (seg->cache.valid==0) {
BX_DEBUG(("execute_virtual_checks(): segment descriptor not valid"));
return 0;
}
if (seg->cache.p == 0) { /* not present */
BX_ERROR(("execute_virtual_checks(): segment not present"));
return 0;
}
switch (seg->cache.type) {
case 0: case 1: /* read only */
case 2: case 3: /* read/write */
case 10: case 11: /* execute/read */
case 14: case 15: /* execute/read-only, conforming */
if (offset > (seg->cache.u.segment.limit_scaled - length + 1)
|| (length-1 > seg->cache.u.segment.limit_scaled))
{
BX_ERROR(("execute_virtual_checks(): read beyond limit"));
return 0;
}
if (seg->cache.u.segment.limit_scaled >= 15) {
// Mark cache as being OK type for succeeding reads. See notes for
// write checks; similar code.
seg->cache.valid |= SegAccessROK;
if (seg->cache.u.segment.limit_scaled == 0xffffffff)
seg->cache.valid |= SegAccessROK4G;
}
break;
case 8: case 9: /* execute only */
case 12: case 13: /* execute only, conforming */
if (offset > (seg->cache.u.segment.limit_scaled - length + 1)
|| (length-1 > seg->cache.u.segment.limit_scaled))
{
BX_ERROR(("execute_virtual_checks(): read beyond limit execute only"));
return 0;
}
break;
case 4: case 5: /* read only, expand down */
case 6: case 7: /* read/write, expand down */
if (seg->cache.u.segment.d_b)
upper_limit = 0xffffffff;
else
upper_limit = 0x0000ffff;
if ((offset <= seg->cache.u.segment.limit_scaled) ||
(offset > upper_limit) || ((upper_limit - offset) < (length - 1)))
{
BX_ERROR(("execute_virtual_checks(): read beyond limit ED"));
return 0;
}
break;
default:
BX_PANIC(("execute_virtual_checks(): unknown descriptor type=%d", seg->cache.type));
}
return 1;
}
const char *BX_CPU_C::strseg(bx_segment_reg_t *seg)
{
if (seg == &BX_CPU_THIS_PTR sregs[BX_SEG_REG_ES]) return("ES");
else if (seg == &BX_CPU_THIS_PTR sregs[BX_SEG_REG_CS]) return("CS");
else if (seg == &BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS]) return("SS");
else if (seg == &BX_CPU_THIS_PTR sregs[BX_SEG_REG_DS]) return("DS");
else if (seg == &BX_CPU_THIS_PTR sregs[BX_SEG_REG_FS]) return("FS");
else if (seg == &BX_CPU_THIS_PTR sregs[BX_SEG_REG_GS]) return("GS");
else {
BX_PANIC(("undefined segment passed to strseg()!"));
return("??");
}
}
int BX_CPU_C::int_number(unsigned s)
{
if (s == BX_SEG_REG_SS)
return BX_SS_EXCEPTION;
else
return BX_GP_EXCEPTION;
}
#if BX_SupportGuest2HostTLB
Bit8u* BX_CPP_AttrRegparmN(2)
BX_CPU_C::v2h_read_byte(bx_address laddr, bx_bool user)
{
unsigned tlbIndex = BX_TLB_INDEX_OF(laddr, 0);
bx_address lpf = LPFOf(laddr);
bx_TLB_entry *tlbEntry = &BX_CPU_THIS_PTR TLB.entry[tlbIndex];
if (tlbEntry->lpf == lpf) {
// See if the TLB entry privilege level allows us read access
// from this CPL.
if (! (tlbEntry->accessBits & user)) { // Read this pl OK.
bx_hostpageaddr_t hostPageAddr = tlbEntry->hostPageAddr;
Bit32u pageOffset = PAGE_OFFSET(laddr);
Bit8u *hostAddr = (Bit8u*) (hostPageAddr | pageOffset);
return hostAddr;
}
}
return 0;
}
Bit8u* BX_CPP_AttrRegparmN(2)
BX_CPU_C::v2h_write_byte(bx_address laddr, bx_bool user)
{
unsigned tlbIndex = BX_TLB_INDEX_OF(laddr, 0);
bx_address lpf = LPFOf(laddr);
bx_TLB_entry *tlbEntry = &BX_CPU_THIS_PTR TLB.entry[tlbIndex];
if (tlbEntry->lpf == lpf)
{
// See if the TLB entry privilege level allows us write access
// from this CPL.
if (! (tlbEntry->accessBits & (0x2 | user))) {
bx_hostpageaddr_t hostPageAddr = tlbEntry->hostPageAddr;
Bit32u pageOffset = PAGE_OFFSET(laddr);
Bit8u *hostAddr = (Bit8u*) (hostPageAddr | pageOffset);
#if BX_SUPPORT_ICACHE
pageWriteStampTable.decWriteStamp(tlbEntry->ppf);
#endif
return hostAddr;
}
}
return 0;
}
#endif // BX_SupportGuest2HostTLB