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[FAST486]

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Implement the extended opcode group 0x0F, 0x00 (SLDT, STR, LLDT, LTR, VERR, VERW).


svn path=/branches/ntvdm/; revision=61264
This commit is contained in:
Aleksandar Andrejevic 2013-12-13 03:32:41 +00:00
parent de64fe5965
commit 5303c91efa
5 changed files with 315 additions and 3 deletions
Download patch file Download diff file Expand all files Collapse all files

282
lib/fast486/opgroups.c
View file

@ -1700,6 +1700,288 @@ FAST486_OPCODE_HANDLER(Fast486OpcodeGroupFF)
return TRUE;
}
FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F00)
{
UCHAR TableReg[6];
FAST486_MOD_REG_RM ModRegRm;
BOOLEAN AddressSize = State->SegmentRegs[FAST486_REG_CS].Size;
FAST486_SEG_REGS Segment = FAST486_REG_DS;
NO_LOCK_PREFIX();
TOGGLE_ADSIZE(AddressSize);
if (!Fast486ParseModRegRm(State, AddressSize, &ModRegRm))
{
/* Exception occurred */
return FALSE;
}
/* Check for the segment override */
if (State->PrefixFlags & FAST486_PREFIX_SEG)
{
/* Use the override segment instead */
Segment = State->SegmentOverride;
}
/* Check which operation this is */
switch (ModRegRm.Register)
{
/* SLDT */
case 0:
{
if (!ModRegRm.Memory)
{
/* The second operand must be a memory location */
Fast486Exception(State, FAST486_EXCEPTION_UD);
return FALSE;
}
/* Fill the 6-byte table register */
RtlCopyMemory(TableReg, &State->Ldtr.Size, sizeof(USHORT));
RtlCopyMemory(&TableReg[sizeof(USHORT)], &State->Ldtr.Address, sizeof(ULONG));
/* Store the LDTR */
return Fast486WriteMemory(State,
Segment,
ModRegRm.MemoryAddress,
TableReg,
sizeof(TableReg));
}
/* STR */
case 1:
{
/* Not recognized in real mode or virtual 8086 mode */
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
|| State->Flags.Vm)
{
Fast486Exception(State, FAST486_EXCEPTION_UD);
}
return Fast486WriteModrmWordOperands(State,
&ModRegRm,
FALSE,
State->TaskReg.Selector);
}
/* LLDT */
case 2:
{
/* This is a privileged instruction */
if (Fast486GetCurrentPrivLevel(State) != 0)
{
Fast486Exception(State, FAST486_EXCEPTION_GP);
return FALSE;
}
if (!ModRegRm.Memory)
{
/* The second operand must be a memory location */
Fast486Exception(State, FAST486_EXCEPTION_UD);
return FALSE;
}
/* Read the new LDTR */
if (!Fast486ReadMemory(State,
Segment,
ModRegRm.MemoryAddress,
FALSE,
TableReg,
sizeof(TableReg)))
{
/* Exception occurred */
return FALSE;
}
/* Load the new LDT */
State->Ldtr.Size = *((PUSHORT)TableReg);
State->Ldtr.Address = *((PULONG)&TableReg[sizeof(USHORT)]);
return TRUE;
}
/* LTR */
case 3:
{
USHORT Selector;
FAST486_TSS_DESCRIPTOR GdtEntry;
/* Not recognized in real mode or virtual 8086 mode */
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
|| State->Flags.Vm)
{
Fast486Exception(State, FAST486_EXCEPTION_UD);
}
/* This is a privileged instruction */
if (Fast486GetCurrentPrivLevel(State) != 0)
{
Fast486Exception(State, FAST486_EXCEPTION_GP);
return FALSE;
}
if (!Fast486ReadModrmWordOperands(State,
&ModRegRm,
NULL,
&Selector))
{
/* Exception occurred */
return FALSE;
}
/* Make sure the GDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Gdtr.Size + 1))
{
Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP, Selector);
return FALSE;
}
/* Read the GDT */
if (!Fast486ReadLinearMemory(State,
State->Gdtr.Address
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))
{
/* Exception occurred */
return FALSE;
}
if (GET_SEGMENT_INDEX(Selector) == 0)
{
Fast486Exception(State, FAST486_EXCEPTION_GP);
return FALSE;
}
if (!GdtEntry.Present)
{
Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_NP, Selector);
return FALSE;
}
if (GdtEntry.Signature != FAST486_TSS_SIGNATURE)
{
/* This is not a TSS descriptor */
Fast486ExceptionWithErrorCode(State, FAST486_EXCEPTION_GP, Selector);
return FALSE;
}
/* Update the TR */
State->TaskReg.Selector = Selector;
State->TaskReg.Base = GdtEntry.Base | (GdtEntry.BaseMid << 16) | (GdtEntry.BaseHigh << 24);
State->TaskReg.Limit = GdtEntry.Limit | (GdtEntry.LimitHigh << 16);
if (GdtEntry.Granularity) State->TaskReg.Limit <<= 12;
State->TaskReg.Busy = TRUE;
return TRUE;
}
/* VERR/VERW */
case 4:
case 5:
{
USHORT Selector;
FAST486_GDT_ENTRY GdtEntry;
/* Not recognized in real mode or virtual 8086 mode */
if (!(State->ControlRegisters[FAST486_REG_CR0] & FAST486_CR0_PE)
|| State->Flags.Vm)
{
Fast486Exception(State, FAST486_EXCEPTION_UD);
}
/* This is a privileged instruction */
if (Fast486GetCurrentPrivLevel(State) != 0)
{
Fast486Exception(State, FAST486_EXCEPTION_GP);
return FALSE;
}
if (!Fast486ReadModrmWordOperands(State,
&ModRegRm,
NULL,
&Selector))
{
/* Exception occurred */
return FALSE;
}
if (!(Selector & SEGMENT_TABLE_INDICATOR))
{
/* Make sure the GDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Gdtr.Size + 1))
{
/* Clear ZF */
State->Flags.Zf = FALSE;
return TRUE;
}
/* Read the GDT */
if (!Fast486ReadLinearMemory(State,
State->Gdtr.Address
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))
{
/* Exception occurred */
return FALSE;
}
}
else
{
/* Make sure the LDT contains the entry */
if (GET_SEGMENT_INDEX(Selector) >= (State->Ldtr.Size + 1))
{
/* Clear ZF */
State->Flags.Zf = FALSE;
return TRUE;
}
/* Read the LDT */
if (!Fast486ReadLinearMemory(State,
State->Ldtr.Address
+ GET_SEGMENT_INDEX(Selector),
&GdtEntry,
sizeof(GdtEntry)))
{
/* Exception occurred */
return FALSE;
}
}
/* Set ZF if it is valid and accessible */
State->Flags.Zf = GdtEntry.Present // must be present
&& GdtEntry.SystemType // must be a segment
&& (((ModRegRm.Register == 4)
/* code segments are only readable if the RW bit is set */
&& (!GdtEntry.Executable || GdtEntry.ReadWrite))
|| ((ModRegRm.Register == 5)
/* code segments are never writable, data segments are writable when RW is set */
&& (!GdtEntry.Executable && GdtEntry.ReadWrite)))
/*
* for segments other than conforming code segments,
* both RPL and CPL must be less than or equal to DPL
*/
&& ((!GdtEntry.Executable || !GdtEntry.DirConf)
&& ((GET_SEGMENT_RPL(Selector) <= GdtEntry.Dpl)
&& (Fast486GetCurrentPrivLevel(State) <= GdtEntry.Dpl)))
/* for conforming code segments, DPL must be less than or equal to CPL */
&& ((GdtEntry.Executable && GdtEntry.DirConf)
&& (GdtEntry.Dpl <= Fast486GetCurrentPrivLevel(State)));
return TRUE;
}
/* Invalid */
default:
{
Fast486Exception(State, FAST486_EXCEPTION_UD);
return FALSE;
}
}
}
FAST486_OPCODE_HANDLER(Fast486OpcodeGroup0F01)
{
UCHAR TableReg[6];