razzle/kernel/syscall/syscall.c
2025-02-28 21:25:17 -05:00

150 lines
3 KiB
C

#include "./syscall.h"
#include "../drivers/ps2/ps2.h"
#include "../io/io.h"
#include "../pci/pci.h"
#include "../scheduler/scheduler.h"
#ifdef ARCH_I386
#include "../../arch/i386/syscall.h"
#endif
enum syscall_type_d {
SYSCALL_yield,
SYSCALL_getc,
SYSCALL_exit,
SYSCALL_lspci,
SYSCALL_lsproc,
SYSCALL_powerctl
};
void powerctl(uint32_t power_mode) {
// TODO: Add reboot mode when ACPI is done
INVOKE_SYSCALL(SYSCALL_powerctl);
}
void yield() { INVOKE_SYSCALL(SYSCALL_yield); }
char getc() {
INVOKE_SYSCALL(SYSCALL_getc);
char result;
__asm__ volatile("movb %%al, %0" : "=r"(result));
return result;
}
uint32_t lspci(struct pci_device *devlist, uint32_t len) {
int result = 0;
__asm__ volatile("movl %0, %%ebx" : : "r"((uint32_t)devlist) : "%ebx");
__asm__ volatile("movl %0, %%ecx" : : "r"(len) : "%ecx");
INVOKE_SYSCALL(SYSCALL_lspci);
__asm__ volatile("movl %%eax, %k0" : "=r"(result));
return result;
}
uint32_t lsproc(struct task_struct *proclist, uint32_t len) {
int result = 0;
__asm__ volatile("movl %0, %%ebx" : : "r"((uint32_t)proclist) : "%ebx");
__asm__ volatile("movl %0, %%ecx" : : "r"(len) : "%ecx");
INVOKE_SYSCALL(SYSCALL_lsproc);
__asm__ volatile("movl %%eax, %k0" : "=r"(result));
return result;
}
void __syscall_powerctl() {
// TODO: Implement properly
printf_nolock("Attempting shutdown using hypervisor-specific methods.");
printf_nolock("ACPI is not yet supported.");
outw(0x604, 0x2000);
outw(0x4004, 0x3400);
outw(0x600, 0x34);
outw(0xB004, 0x2000);
}
void __syscall_yield(struct regs *r) {
// for now, just reschedule
// TODO: reset PIT timer so
// next process doesn't get an
// unreasonably small quantum
schedule(r);
}
void syscall(struct regs *r) {
int syscall_no = r->eax;
switch (syscall_no) {
case SYSCALL_powerctl: {
__syscall_powerctl();
break;
};
case SYSCALL_yield: {
__syscall_yield(r);
break;
};
case SYSCALL_getc: {
process_table[current_pid].state = TASKSTATE_blocked;
for (uint32_t i = 0; i < MAX_PROCESSES; i++) {
if (!ps2_waiters[i].alloc) {
ps2_waiters[i].alloc = 1;
ps2_waiters[i].pid = current_pid;
break;
}
}
__syscall_yield(r);
break;
};
case SYSCALL_lspci: {
uint32_t len = r->ecx;
len = len < pci_devices_count ? len : pci_devices_count;
struct pci_device *devlist = (struct pci_device *)r->ebx;
for (uint32_t i = 0; i < len; ++i) {
devlist[i] = pci_devices_list[i];
}
r->eax = len;
break;
};
case SYSCALL_lsproc: {
uint32_t len = r->ecx;
struct task_struct *proclist = (struct task_struct *)r->ebx;
uint32_t i = 0, j = 0;
for (; i < len; ++i, ++j) {
for (; j < MAX_PROCESSES && process_table[j].state == TASKSTATE_unused;
++j) {
}
if (j == MAX_PROCESSES)
break;
proclist[i] = process_table[j];
}
r->eax = i;
break;
};
case SYSCALL_exit: {
process_table[current_pid].state = TASKSTATE_unused;
__syscall_yield(r);
break;
};
}
}