#include #include #include #include #include #include #include #include #define RET(type, name) type *name = (type *)(¤t_pcb->regs->rax) #define ARG1(type, name) type name = (type)(current_pcb->regs->rdi) #define ARG2(type, name) type name = (type)(current_pcb->regs->rsi) #define ARG3(type, name) type name = (type)(current_pcb->regs->rdx) #define ARG4(type, name) type name = (type)(current_pcb->regs->rcx) static int sys_exit(void) { ARG1(int, status); (void)status; // FIXME: schedule somthing else while (1) ; return 1; } static int sys_write(void) { ARG1(int, fd); ARG2(const void *, buffer); ARG3(size_t, nbytes); const char *map_buf = kmapuseraddr(current_pcb->memctx, buffer, nbytes); if (map_buf == NULL) return 0; // cannot write to stdin if (fd == 0) nbytes = 0; // write to stdout else if (fd == 1) { for (size_t i = 0; i < nbytes; i++) kputc(map_buf[i]); } // files else { // TODO: write to files nbytes = 0; } kunmapaddr(map_buf); return nbytes; } static int sys_poweroff(void) { // TODO: we should probably // kill all user processes // and then sync the fs acpi_shutdown(); return 1; } static int sys_drm(void) { ARG1(void **, res_fb); ARG2(int *, res_width); ARG3(int *, res_height); ARG4(int *, res_bpp); void *pADDR, *vADDR; int width, height, bpp; size_t len; if (gpu_dev == NULL) return 1; len = gpu_dev->width * gpu_dev->height * gpu_dev->bit_depth / 8; pADDR = mem_get_phys(kernel_mem_ctx, (void *)(uintptr_t)gpu_dev->framebuffer); if (pADDR == NULL) return 1; vADDR = mem_mapaddr(current_pcb->memctx, pADDR, (void *)0x1000000000, len, F_PRESENT | F_WRITEABLE | F_UNPRIVILEGED); if (vADDR == NULL) return 1; width = gpu_dev->width; height = gpu_dev->height; bpp = gpu_dev->bit_depth; mem_ctx_switch(current_pcb->memctx); *res_fb = vADDR; *res_width = width; *res_height = height; *res_bpp = bpp; mem_ctx_switch(kernel_mem_ctx); return 0; } static int sys_ticks(void) { RET(uint64_t, res_ticks); *res_ticks = ticks; return 0; } static int (*syscall_tbl[N_SYSCALLS])(void) = { [SYS_exit] = sys_exit, [SYS_waitpid] = NULL, [SYS_fork] = NULL, [SYS_exec] = NULL, [SYS_open] = NULL, [SYS_close] = NULL, [SYS_read] = NULL, [SYS_write] = sys_write, [SYS_getpid] = NULL, [SYS_getppid] = NULL, [SYS_gettime] = NULL, [SYS_getprio] = NULL, [SYS_setprio] = NULL, [SYS_kill] = NULL, [SYS_sleep] = NULL, [SYS_brk] = NULL, [SYS_sbrk] = NULL, [SYS_poweroff] = sys_poweroff, [SYS_drm] = sys_drm, [SYS_ticks] = sys_ticks, }; void syscall_handler(struct cpu_regs *regs) { uint64_t num; int (*handler)(void); int ret = 1; // make sure were in the kernel memory context mem_ctx_switch(kernel_mem_ctx); // update data current_pcb->regs = regs; num = current_pcb->regs->rax; current_pcb->regs->rax = 0; // syscall number // check for invalid syscall if (num >= N_SYSCALLS) { // invalid syscall // FIXME: kill user process while (1) ; } // run syscall handler handler = syscall_tbl[num]; if (handler != NULL) ret = handler(); // on failure, set rax if (ret) current_pcb->regs->rax = ret; }