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[EXTERN kernel_stack_top]
[EXTERN run_scheduler]
[GLOBAL save_context_and_enter_scheduler]
; void save_context_and_enter_scheduler(struct saved_context *ctx);
save_context_and_enter_scheduler:
pushf
cli
pusha ; Pushes edi,esi,ebp,esp,ebx,edx,ecx,eax
mov eax, cr3
push eax
mov ax, ds ; Lower 16-bits of eax = ds.
push eax ; save the data segment descriptor
mov eax, [esp+48] ; get address of saved_context structure
mov [eax], esp ; save esp
mov dword [eax+4], resume_saved_context ; save eip
mov esp, kernel_stack_top
jmp run_scheduler
resume_saved_context:
pop eax
mov ds, ax
mov es, ax
mov fs, ax
mov gs, ax
pop eax
mov cr3, eax
popa
popf
ret
[GLOBAL resume_context]
resume_context:
mov eax, [esp+4] ; get address of saved context
mov esp, [eax] ; resume esp
mov ecx, [eax+4] ; jump to specified eip
jmp ecx
; vim: set ts=4 sw=4 tw=0 noet :
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