; $Id: bs3-cmn-RegGetCr3.asm 98103 2023-01-17 14:15:46Z vboxsync $ ;; @file ; BS3Kit - Bs3RegGetCr3 ; ; ; Copyright (C) 2007-2023 Oracle and/or its affiliates. ; ; This file is part of VirtualBox base platform packages, as ; available from https://www.virtualbox.org. ; ; This program is free software; you can redistribute it and/or ; modify it under the terms of the GNU General Public License ; as published by the Free Software Foundation, in version 3 of the ; License. ; ; This program 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 ; General Public License for more details. ; ; You should have received a copy of the GNU General Public License ; along with this program; if not, see . ; ; The contents of this file may alternatively be used under the terms ; of the Common Development and Distribution License Version 1.0 ; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included ; in the VirtualBox distribution, in which case the provisions of the ; CDDL are applicable instead of those of the GPL. ; ; You may elect to license modified versions of this file under the ; terms and conditions of either the GPL or the CDDL or both. ; ; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 ; %include "bs3kit-template-header.mac" BS3_EXTERN_CMN Bs3Panic BS3_EXTERN_CMN Bs3Syscall %if TMPL_BITS == 16 BS3_EXTERN_DATA16 g_bBs3CurrentMode %endif TMPL_BEGIN_TEXT ;; ; @cproto BS3_CMN_PROTO_STUB(RTCCUINTXREG, Bs3RegGetCr3,(void)); ; ; @returns Register value. ; @remarks Does not require 20h of parameter scratch space in 64-bit mode. ; ; @uses No GPRs (only return full register(s)). ; BS3_PROC_BEGIN_CMN Bs3RegGetCr3, BS3_PBC_HYBRID_SAFE BS3_CALL_CONV_PROLOG 0 push xBP mov xBP, xSP %if TMPL_BITS == 16 ; If V8086 mode we have to go thru a syscall. test byte [BS3_DATA16_WRT(g_bBs3CurrentMode)], BS3_MODE_CODE_V86 jnz .via_system_call cmp byte [BS3_DATA16_WRT(g_bBs3CurrentMode)], BS3_MODE_RM je .direct_access %endif ; If not in ring-0, we have to make a system call. mov ax, ss and ax, X86_SEL_RPL jnz .via_system_call .direct_access: mov sAX, cr3 TONLY16 mov edx, eax TONLY16 shr edx, 16 jmp .return .via_system_call: mov xAX, BS3_SYSCALL_GET_CRX mov dl, 3 call Bs3Syscall .return: pop xBP BS3_CALL_CONV_EPILOG 0 BS3_HYBRID_RET BS3_PROC_END_CMN Bs3RegGetCr3