remove obsolete code to handle classical syscalls

hermit/arch/x86/kernel/entry.asm

@@ -416,83 +416,6 @@ extern finish_task_switch
 extern syscall_handler
 extern kernel_stack
 
-; libos => no syscall interface required
-%if 0
-global isrsyscall
-align 64
-; used to realize system calls
-isrsyscall:
-    ; IF flag is already cleared
-    ; cli
-
-    ; only called from user space => get kernel-level selector
-    swapgs
-
-    ; get kernel stack
-    xchg rsp, [gs:kernel_stack]
-
-    ; push old rsp and restore [gs:kernel_stack]
-    push QWORD [gs:kernel_stack]
-    mov QWORD [gs:kernel_stack], rsp
-
-    ; save registers accross function call
-    push r8
-    push r9
-    push r10
-    push r11
-    push rdx
-    push rcx
-    push rdi
-    push rsi
-
-    ; syscall stores in rcx the return address
-    ; => using of r10 for the temporary storage of the 4th argument
-    mov rcx, r10
-
-    ; during a system call, HermitCore allows interrupts
-    sti
-
-    extern syscall_table
-    call [rax*8+syscall_table]
-    push rax ; result, which we have to return
-
-%ifdef DYNAMIC_TICKS
-    extern check_ticks
-    call check_ticks
-%endif
-
-    extern check_timers
-    call check_timers
-
-    extern check_scheduling
-    call check_scheduling
-
-    cli
-
-    ; restore return value
-    pop rax
-
-    ; restore registers
-    pop rsi
-    pop rdi
-    pop rcx
-    pop rdx
-    pop r11
-    pop r10
-    pop r9
-    pop r8
-
-    ; restore user-level stack
-    mov rsp, [rsp]
-
-    ; set user-level selector
-    swapgs
-
-    ; EFLAGS (and IF flag) will be restored by sysret
-    ; sti
-    o64 sysret
-%endif
-
 global getcontext
 align 64
 getcontext:

hermit/kernel/syscall.c

@@ -643,24 +643,3 @@ int sys_signal(signal_handler_t handler)
 {
 	return hermit_signal(handler);
 }
-
-static int default_handler(void)
-{
-#if 1
-	kprintf("Invalid system call\n");
-#else
-	uint64_t rax;
-
-	asm volatile ("mov %%rax, %0" : "=m"(rax) :: "memory");
-	kprintf("Invalid system call: %zd\n", rax);
-#endif
-	return -ENOSYS;
-}
-
-/* 
- * Currently our sytemcall table is a dummy table for
- * future developments.
- */
-size_t syscall_table[] = {
-	(size_t) default_handler
-};