9778b7b790
git-svn-id: http://svn.lfbs.rwth-aachen.de/svn/scc/trunk/MetalSVM@2 315a16e6-25f9-4109-90ae-ca3045a26c18
107 lines
2.4 KiB
NASM
107 lines
2.4 KiB
NASM
;
|
|
; Copyright 2010 Stefan Lankes, Chair for Operating Systems,
|
|
; RWTH Aachen University
|
|
;
|
|
; Licensed under the Apache License, Version 2.0 (the "License");
|
|
; you may not use this file except in compliance with the License.
|
|
; You may obtain a copy of the License at
|
|
;
|
|
; http://www.apache.org/licenses/LICENSE-2.0
|
|
;
|
|
; Unless required by applicable law or agreed to in writing, software
|
|
; distributed under the License is distributed on an "AS IS" BASIS,
|
|
; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
; See the License for the specific language governing permissions and
|
|
; limitations under the License.
|
|
;
|
|
; This file is part of metalsvm.
|
|
|
|
[BITS 32]
|
|
SECTION .code
|
|
extern get_new_task
|
|
extern current_task
|
|
;extern task_table
|
|
|
|
; C prototyp:
|
|
;
|
|
; typedef struct {
|
|
; unsigned char* top;
|
|
; unsigned int ip;
|
|
; tid_t id;
|
|
; unsigned char status;
|
|
; unsigned char idle;
|
|
; } task_t;
|
|
|
|
; After an interrupt, the original return address has to push on the stack
|
|
; because we want to comeback...
|
|
global schedule_entry
|
|
schedule_entry:
|
|
cli
|
|
sub esp, 4 ; add some space for the retunr address,
|
|
; which is stored in current_task->ip
|
|
|
|
pushfd
|
|
pusha
|
|
push ds
|
|
push es
|
|
push fs
|
|
push gs
|
|
mov ax, 0x10
|
|
mov ds, ax
|
|
mov es, ax
|
|
mov fs, ax
|
|
mov gs, ax
|
|
|
|
;mov eax, DWORD [current_id]
|
|
;shl eax, 0x4 ; 16 = sizeof(task_t)
|
|
;mov edx, DWORD [eax+task_table+4]
|
|
;mov [esp+13*4], edx
|
|
;mov DWORD [eax+task_table+4], 0
|
|
mov eax, DWORD [current_task]
|
|
mov edx, [eax+4]
|
|
mov DWORD [esp+13*4], edx
|
|
mov DWORD [eax+4], 0x00
|
|
|
|
jmp L1
|
|
|
|
; Scheduler, which switchs to the new tasks
|
|
global schedule
|
|
schedule:
|
|
cli
|
|
pushfd
|
|
pusha
|
|
push ds
|
|
push es
|
|
push fs
|
|
push gs
|
|
mov ax, 0x10
|
|
mov ds, ax
|
|
mov es, ax
|
|
mov fs, ax
|
|
mov gs, ax
|
|
|
|
; store current esp
|
|
;mov eax, DWORD [current_id]
|
|
;shl eax, 0x4 ; 16 = sizeof(task_t)
|
|
L1:
|
|
;mov [eax+task_table], esp
|
|
mov eax, DWORD [current_task]
|
|
mov [eax], esp
|
|
|
|
call get_new_task
|
|
|
|
; set current task and restore esp
|
|
;mov DWORD [current_id], eax
|
|
;shl eax, 0x4 ; 16 = sizeof(task_t)
|
|
;mov esp, [eax+task_table]
|
|
mov DWORD [current_task], eax
|
|
mov esp, [eax]
|
|
|
|
pop gs
|
|
pop fs
|
|
pop es
|
|
pop ds
|
|
popa
|
|
popfd
|
|
sti
|
|
ret
|