os-k/kaleid/kernel/mm/paging.asm

51 lines
2.2 KiB
NASM

;=----------------------------------------------------------------------------=;
; OS on Kaleid ;
; ;
; Desc: Paging related functions ;
; ;
; ;
; Copyright © 2018-2020 The OS/K Team ;
; ;
; This file is part of OS/K. ;
; ;
; OS/K 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, either version 3 of the License, or ;
; (at your option) any later version. ;
; ;
; OS/K 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 OS/K. If not, see <https://www.gnu.org/licenses/>. ;
;=----------------------------------------------------------------------------=;
global MmEnableWriteProtect
global MmDisableWriteProtect
global MmLoadPML4
MmEnableWriteProtect:
push rax
mov rax, cr0
or rax, 1<<16
mov cr0, rax
pop rax
ret
MmDisableWriteProtect:
push rax
mov rax, cr0
and rax, ~(1<<16)
mov cr0, rax
pop rax
ret
MmLoadPML4:
push rax
mov rax, rdi
mov cr3, rax
pop rax
ret