diff options
Diffstat (limited to 'src/kernel/task/idt.c')
| -rw-r--r-- | src/kernel/task/idt.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/src/kernel/task/idt.c b/src/kernel/task/idt.c index 80f13db..887ebf7 100644 --- a/src/kernel/task/idt.c +++ b/src/kernel/task/idt.c @@ -67,6 +67,8 @@ struct idt_ptr idt_ptr; static int_callback irq_handlers[16] = {0}; static struct thread* irq_wakeup[16] = {0}; +/* Called in idt_.asm when an exception fires (interrupt 0 to 31). + Tries to handle the exception, panics if fails. */ void idt_isrHandler(struct registers regs) { if ((regs.int_no == 14 && paging_fault(®s) != 0) || regs.int_no != 14) { if (tasking_handleException(®s) == 0) { @@ -80,6 +82,8 @@ void idt_isrHandler(struct registers regs) { } } +/* Called in idt_.asm when an IRQ fires (interrupt 32 to 47) + Possibly wakes up a thread that was waiting, possibly calls a handler. */ void idt_irqHandler(struct registers regs) { uint32_t doSwitch = (regs.err_code == 0); //IRQ0 = timer if (regs.err_code > 7) { @@ -97,14 +101,15 @@ void idt_irqHandler(struct registers regs) { if (doSwitch) tasking_switch(); } +/* Called in idt_.asm on a system call (interrupt 64). + Calls the correct syscall handler (if any). */ void idt_syscallHandler(struct registers regs) { - if (syscalls[regs.eax] != 0) { + if (regs.eax < NUMBER_OF_SYSCALLS && syscalls[regs.eax] != 0) { syscalls[regs.eax](®s); - } else { - monitor_write("Unhandled syscall...\n"); } } +/* For internal use only. Sets up an entry of the IDT with given parameters. */ static void idt_setGate(uint8_t num, uint32_t base, uint16_t sel, uint8_t flags) { idt_entries[num].base_lo = base & 0xFFFF; idt_entries[num].base_hi = (base >> 16) & 0xFFFF; @@ -114,6 +119,7 @@ static void idt_setGate(uint8_t num, uint32_t base, uint16_t sel, uint8_t flags) idt_entries[num].flags = flags | 0x60; } +/* Remaps the IRQs. Sets up the IDT. */ void idt_init() { idt_ptr.limit = (sizeof(struct idt_entry) * 256) - 1; idt_ptr.base = (uint32_t)&idt_entries; @@ -189,12 +195,14 @@ void idt_init() { monitor_write("[IDT] "); } +/* Sets up an IRQ handler for given IRQ. */ void idt_handleIrq(int number, int_callback func) { if (number < 16 && number >= 0) { irq_handlers[number] = func; } } +/* Tells the IRQ handler to wake up the current thread when specified IRQ fires. */ void idt_waitIrq(int number) { if (number < 16 && number >= 0 && proc_priv() <= PL_DRIVER) { irq_wakeup[number] = current_thread; |