77 lines
1.3 KiB
C
77 lines
1.3 KiB
C
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#include <stdlib.h>
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#include <string.h>
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#include <drivers/irq.h>
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#include <scheduler.h>
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#define STACK_SIZE (8192)
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task_t* current_task = NULL;
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task_t* task_list = NULL;
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uint32_t next_pid = 1;
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void init_scheduler(void)
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{
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set_irq_handler(0, (irq_func_t) schedule);
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}
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void scheduler(registers_t* boot_regs)
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{
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task_t* task = malloc(sizeof(task_t));
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task->id = next_pid++;
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task->regs = boot_regs;
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task->next = task;
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task_list = task;
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current_task = task;
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}
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registers_t* schedule(registers_t* regs)
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{
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if (!current_task)
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{
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return regs;
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}
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current_task->regs = regs;
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current_task = current_task->next;
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return current_task->regs;
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}
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task_t* create_task(void (*entry)())
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{
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task_t* task = malloc(sizeof(task_t));
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uint32_t* stack = malloc(STACK_SIZE);
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uint32_t stack_top = (uint32_t)stack + 4096;
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stack_top -= sizeof(registers_t);
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registers_t* regs = (registers_t*)stack_top;
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memset(regs, 0, sizeof(registers_t));
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regs->eip = (uint32_t) entry;
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regs->cs = 0x08; /* kernel code */
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regs->ds = 0x10;
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regs->es = 0x10;
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regs->fs = 0x10;
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regs->gs = 0x10;
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regs->eflags = 0x202; /* IF = 1 */
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task->id = next_pid++;
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task->regs = regs;
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/* insert into circular list */
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task->next = task_list->next;
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task_list->next = task;
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return task;
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}
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