task switch progress

This commit is contained in:
rami 2024-07-06 18:00:06 -04:00
parent 1b7474095b
commit 5f025d18bf
5 changed files with 58 additions and 17 deletions

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@ -2,4 +2,4 @@ ata0-slave: type=cdrom, path=./build/Hazel.iso, status=inserted
magic_break: enabled=1
boot: cdrom
display_library: x
display_library: sdl2

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@ -5,7 +5,6 @@
#include <kernel/elf.h>
typedef struct {
uint32_t eip;
uint32_t esp;
uint32_t cr3;
uint32_t *next;

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@ -118,22 +118,22 @@ flush_tss:
extern ctx
global task_switch
task_switch:
; Save current task's registers
push ebx
push esi
push edi
push ebp
mov esi, [ctx+28]
; Return if only one process is running
mov eax, [esi+12]
cmp eax, 0
je ret
; Check if using same virtual memory
cmp [esi+8], [eax+8]
je .ret
mov ecx, [eax+8]
mov cr3, ecx
.ret:
mov edi, [ctx+28] ; EDI = current task
mov esi, [esp+20] ; ESI = next task
; Save current ESP
mov dword [edi], esp
; Set current task to next task
mov dword [ctx+28], esi
; Change to new ESP
mov esp, [esi]
mov ecx, [esi+4]
pop ebp
pop edi
pop esi

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@ -18,6 +18,7 @@ extern uint32_t isr_stub_table[32];
extern void pit_isr(void);
extern void jmp_user_mode(uint32_t esp, uint32_t eip);
extern void flush_tss(uint32_t segment_selector);
extern void task_switch(task_t *task);
extern gdt_t gdt[6];
extern uint32_t boot_page_dir[1024];
extern uint32_t boot_page_tab[1024];
@ -35,7 +36,7 @@ void sleep(int delay) {
cpu_relax;
}
void idt_init() {
void idt_init(void) {
for (int i = 0; i < 32; i++) {
idt_encode_entry(idt, i, isr_stub_table[i], GDT_SEGMENT_SELECTOR(GDT_KERNEL_CODE, RING0), TRAP_GATE_32 | INT_RING0 | INT_PRESENT);
}
@ -47,6 +48,13 @@ void idt_init() {
asm volatile ("lidt %0" :: "m"(idtr));
}
void test(void) {
for (int i = 0; i < 1000; i++) {
LOG("O");
}
task_switch((task_t *)ctx.current_task->next);
}
void kernel(multiboot_info_t *info) {
if (!CHECK_FLAG(info->flags, 3)) goto halt; // Modules
if (!CHECK_FLAG(info->flags, 6)) goto halt; // Memory map
@ -61,14 +69,12 @@ void kernel(multiboot_info_t *info) {
LOG("%d bytes of RAM detected\nCreated a %d byte large physical memory map at 0x%08X\n", ctx.mmap_size*BLOCK_SIZE*8, ctx.mmap_size, (uint32_t)ctx.mmap);
idt_init();
/*
/*
pic_remap(PIC_1_START, PIC_2_START);
asm volatile ("sti" ::);
ctx.ticks = 0;
pit_init();
*/
// Setup TSS
uint32_t base = (uint32_t)&tss;
uint32_t limit = base + sizeof(tss_t);
@ -87,6 +93,30 @@ void kernel(multiboot_info_t *info) {
tss.ss = tss.ds = tss.es = tss.fs = tss.gs = GDT_SEGMENT_SELECTOR(GDT_USER_DATA, RING3);
flush_tss(GDT_SEGMENT_SELECTOR(5, RING3));
task_t task1 = {0};
task_t task2 = {0};
task1.cr3 = (uint32_t)boot_page_dir - KERNEL_VMA;
task1.next = (uint32_t *)&task2;
ctx.current_task = &task1;
uint32_t *stack = mmap_find_first_free_block();
asm volatile ("mov %%esp, %0" : "=r" (task1.esp));
stack[1023] = (uint32_t)test;
stack[1022] = 0;
stack[1021] = 0;
stack[1020] = 0;
stack[1019] = 0;
task2.esp = (uint32_t)stack + (0x1000 - 20);
task2.cr3 = (uint32_t)boot_page_dir - KERNEL_VMA;
task2.next = (uint32_t *)&task1;
//task_switch(&task2);
for (int i = 0; i < 1000; i++) {
LOG("_");
}
task_switch((task_t *)ctx.current_task->next);
task_switch((task_t *)ctx.current_task->next);
/*
multi_mod_t *init = (multi_mod_t *)(info->moduleaddress + KERNEL_VMA);
elf_t *elf = (elf_t *)(init->mod_start+KERNEL_VMA);
task_t task = {0};
@ -97,6 +127,7 @@ void kernel(multiboot_info_t *info) {
LOG("Switching to ring 3... EIP: 0x%08X ESP: 0x%08X\n", task.eip, task.esp);
jmp_user_mode(task.esp, task.eip);
*/
halt:
for (;;) {}

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@ -12,9 +12,20 @@ void pit_init(void) {
outb(PIT_CHAN0_DATA, (uint8_t)((DIVISOR & 0xff00) >> 8));
}
extern void task_switch(task_t *task);
void pit_handler(void) {
ctx.ticks++;
if (ctx.current_task->next) {
LOG("TASK SWITCH\n");
//task_t *old = ctx.current_task;
//task_t *new = (task_t *)ctx.current_task->next;
//new->next = (uint32_t *)old;
//old->next = (uint32_t *)new;
task_switch((task_t *)ctx.current_task->next);
}
outb(PIT_CHAN0_DATA, (uint8_t)(DIVISOR & 0xff));
outb(PIT_CHAN0_DATA, (uint8_t)((DIVISOR & 0xff00) >> 8));
pic_send_eoi(0);