Bochs/bochs/cpu/ret_far.cc
Stanislav Shwartsman 7b6c2587a9 Now devices could be compiled separatelly from CPU
Averything that required cpu.h include now has it explicitly and there are a lot of files not dependant by CPU at all which will compile a lot faster now ...
2006-03-06 22:03:16 +00:00

301 lines
10 KiB
C++
Executable File

////////////////////////////////////////////////////////////////////////
// $Id: ret_far.cc,v 1.5 2006-03-06 22:03:02 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
#if BX_SUPPORT_X86_64==0
// Make life easier merging cpu64 & cpu code.
#define RIP EIP
#define RSP ESP
#endif
void BX_CPP_AttrRegparmN(2)
BX_CPU_C::return_protected(bxInstruction_c *i, Bit16u pop_bytes)
{
Bit16u raw_cs_selector, raw_ss_selector;
bx_selector_t cs_selector, ss_selector;
bx_descriptor_t cs_descriptor, ss_descriptor;
Bit32u stack_param_offset;
bx_address return_RIP, return_RSP, temp_RSP;
Bit32u dword1, dword2;
/* + 6+N*2: SS | +12+N*4: SS | +24+N*8 SS */
/* + 4+N*2: SP | + 8+N*4: ESP | +16+N*8 RSP */
/* parm N | + parm N | + parm N */
/* parm 3 | + parm 3 | + parm 3 */
/* parm 2 | + parm 2 | + parm 2 */
/* + 4: parm 1 | + 8: parm 1 | +16: parm 1 */
/* + 2: CS | + 4: CS | + 8: CS */
/* + 0: IP | + 0: EIP | + 0: RIP */
#if BX_SUPPORT_X86_64
if (StackAddrSize64()) temp_RSP = RSP;
else
#endif
{
if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b) temp_RSP = ESP;
else temp_RSP = SP;
}
#if BX_SUPPORT_X86_64
if ( i->os64L() ) {
/* operand size=64: 2nd qword on stack must be within stack limits,
* else #SS(0); */
if (!can_pop(16))
{
BX_ERROR(("return_protected: 2rd qword not in stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 8,
2, CPL==3, BX_READ, &raw_cs_selector);
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 0,
8, CPL==3, BX_READ, &return_RIP);
stack_param_offset = 16;
}
else
#endif
if ( i->os32L() ) {
/* operand size=32: 2nd dword on stack must be within stack limits,
* else #SS(0); */
if (!can_pop(8))
{
BX_ERROR(("return_protected: 2rd dword not in stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
Bit32u return_EIP = 0;
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 4,
2, CPL==3, BX_READ, &raw_cs_selector);
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 0,
4, CPL==3, BX_READ, &return_EIP);
return_RIP = return_EIP;
stack_param_offset = 8;
}
else {
/* operand size=16: second word on stack must be within stack limits,
* else #SS(0); */
if ( !can_pop(4) )
{
BX_ERROR(("return_protected: 2nd word not in stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
Bit16u return_IP = 0;
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 2,
2, CPL==3, BX_READ, &raw_cs_selector);
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 0,
2, CPL==3, BX_READ, &return_IP);
return_RIP = return_IP;
stack_param_offset = 4;
}
// selector must be non-null else #GP(0)
if ( (raw_cs_selector & 0xfffc) == 0 ) {
BX_INFO(("return_protected: CS selector null"));
exception(BX_GP_EXCEPTION, 0, 0);
}
parse_selector(raw_cs_selector, &cs_selector);
// selector index must be within its descriptor table limits,
// else #GP(selector)
fetch_raw_descriptor(&cs_selector, &dword1, &dword2, BX_GP_EXCEPTION);
// descriptor AR byte must indicate code segment, else #GP(selector)
parse_descriptor(dword1, dword2, &cs_descriptor);
// return selector RPL must be >= CPL, else #GP(return selector)
if (cs_selector.rpl < CPL) {
BX_ERROR(("return_protected: CS.rpl < CPL"));
exception(BX_GP_EXCEPTION, raw_cs_selector & 0xfffc, 0);
}
// check code-segment descriptor
check_cs(&cs_descriptor, raw_cs_selector, 0, cs_selector.rpl);
// if return selector RPL == CPL then
// RETURN TO SAME PRIVILEGE LEVEL
if (cs_selector.rpl == CPL)
{
BX_DEBUG(("return_protected: return to SAME PRIVILEGE LEVEL"));
// top word on stack must be within stack limits, else #SS(0)
if (! can_pop(stack_param_offset + pop_bytes)) {
BX_ERROR(("return_protected: top word not in stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
branch_far64(&cs_selector, &cs_descriptor, return_RIP, CPL);
#if BX_SUPPORT_X86_64
if (StackAddrSize64())
RSP += stack_param_offset + pop_bytes;
else
#endif
{
if (BX_CPU_THIS_PTR sregs[BX_SEG_REG_SS].cache.u.segment.d_b)
ESP += stack_param_offset + pop_bytes;
else
SP += stack_param_offset + pop_bytes;
}
return;
}
/* RETURN TO OUTER PRIVILEGE LEVEL */
else {
/* + 6+N*2: SS | +12+N*4: SS | +24+N*8 SS */
/* + 4+N*2: SP | + 8+N*4: ESP | +16+N*8 RSP */
/* parm N | + parm N | + parm N */
/* parm 3 | + parm 3 | + parm 3 */
/* parm 2 | + parm 2 | + parm 2 */
/* + 4: parm 1 | + 8: parm 1 | +16: parm 1 */
/* + 2: CS | + 4: CS | + 8: CS */
/* + 0: IP | + 0: EIP | + 0: RIP */
#if BX_SUPPORT_X86_64
if (i->os64L()) {
/* top 32+immediate bytes on stack must be within stack limits, else #SS(0) */
if ( !can_pop(32 + pop_bytes) ) {
BX_ERROR(("return_protected: 32 bytes not within stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 24 + pop_bytes,
2, 0, BX_READ, &raw_ss_selector);
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 16 + pop_bytes,
8, 0, BX_READ, &return_RSP);
}
else
#endif
if (i->os32L()) {
/* top 16+immediate bytes on stack must be within stack limits, else #SS(0) */
if ( !can_pop(16 + pop_bytes) ) {
BX_ERROR(("return_protected: 16 bytes not within stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
Bit32u return_ESP = 0;
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 12 + pop_bytes,
2, 0, BX_READ, &raw_ss_selector);
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 8 + pop_bytes,
4, 0, BX_READ, &return_ESP);
return_RSP = return_ESP;
}
else {
/* top 8+immediate bytes on stack must be within stack limits, else #SS(0) */
if ( !can_pop(8 + pop_bytes) ) {
BX_ERROR(("return_protected: 8 bytes not within stack limits"));
exception(BX_SS_EXCEPTION, 0, 0);
}
Bit16u return_SP = 0;
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 6 + pop_bytes,
2, 0, BX_READ, &raw_ss_selector);
access_linear(BX_CPU_THIS_PTR get_segment_base(BX_SEG_REG_SS) + temp_RSP + 4 + pop_bytes,
2, 0, BX_READ, &return_SP);
return_RSP = return_SP;
}
/* selector index must be within its descriptor table limits,
* else #GP(selector) */
parse_selector(raw_ss_selector, &ss_selector);
if ((raw_ss_selector & 0xfffc) == 0) {
if (IsLongMode()) {
if (! IS_LONG64_SEGMENT(cs_descriptor) || (cs_selector.rpl == 3)) {
BX_ERROR(("return_protected: SS selector null"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
else // not in long or compatibility mode
{
BX_ERROR(("return_protected: SS selector null"));
exception(BX_GP_EXCEPTION, 0, 0);
}
}
fetch_raw_descriptor(&ss_selector, &dword1, &dword2, BX_GP_EXCEPTION);
parse_descriptor(dword1, dword2, &ss_descriptor);
/* selector RPL must = RPL of the return CS selector,
* else #GP(selector) */
if (ss_selector.rpl != cs_selector.rpl) {
BX_ERROR(("return_protected: ss.rpl != cs.rpl"));
exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0);
}
/* descriptor AR byte must indicate a writable data segment,
* else #GP(selector) */
if (ss_descriptor.valid==0 || ss_descriptor.segment==0 ||
ss_descriptor.u.segment.executable ||
ss_descriptor.u.segment.r_w==0)
{
BX_PANIC(("return_protected: SS.AR byte not writable data"));
exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0);
}
/* descriptor dpl must = RPL of the return CS selector,
* else #GP(selector) */
if (ss_descriptor.dpl != cs_selector.rpl) {
BX_ERROR(("return_protected: SS.dpl != cs.rpl"));
exception(BX_GP_EXCEPTION, raw_ss_selector & 0xfffc, 0);
}
/* segment must be present else #SS(selector) */
if (! IS_PRESENT(ss_descriptor)) {
BX_ERROR(("return_protected: ss.present == 0"));
exception(BX_SS_EXCEPTION, raw_ss_selector & 0xfffc, 0);
}
branch_far64(&cs_selector, &cs_descriptor, return_RIP, cs_selector.rpl);
/* load SS:SP from stack */
/* load SS-cache with return SS descriptor */
load_ss(&ss_selector, &ss_descriptor, cs_selector.rpl);
#if BX_SUPPORT_X86_64
if (StackAddrSize64()) RSP = return_RSP + pop_bytes;
else
#endif
if (ss_descriptor.u.segment.d_b)
ESP = (Bit32u) return_RSP + pop_bytes;
else
SP = (Bit16u) return_RSP + pop_bytes;
/* check ES, DS, FS, GS for validity */
validate_seg_regs();
}
}