remove dependencies to rust feature "naked functions"

src/arch/mod.rs

@@ -60,8 +60,6 @@ pub use crate::arch::x86_64::kernel::processor;
 #[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::kernel::scheduler;
 #[cfg(target_arch = "x86_64")]
-pub use crate::arch::x86_64::kernel::switch::{switch_to_fpu_owner, switch_to_task};
-#[cfg(target_arch = "x86_64")]
 pub use crate::arch::x86_64::kernel::systemtime::get_boot_time;
 #[cfg(not(test))]
 #[cfg(target_arch = "x86_64")]
@@ -72,3 +70,14 @@ pub use crate::arch::x86_64::kernel::{
 pub use crate::arch::x86_64::kernel::{
 	get_processor_count, message_output_init, output_message_buf, output_message_byte,
 };
+
+#[cfg(test)]
+pub fn switch_to_task(_old_stack: *mut usize, _new_stack: usize) {}
+#[cfg(test)]
+pub fn switch_to_fpu_owner(_old_stack: *mut usize, _new_stack: usize) {}
+
+#[cfg(not(test))]
+extern "C" {
+	pub fn switch_to_task(old_stack: *mut usize, new_stack: usize);
+	pub fn switch_to_fpu_owner(old_stack: *mut usize, new_stack: usize);
+}

src/arch/x86_64/kernel/apic.rs

@@ -518,6 +518,10 @@ pub fn init_next_processor_variables(core_id: CoreId) {
 	}
 }
 
+extern "C" {
+	fn _start();
+}
+
 /// Boot all Application Processors
 /// This algorithm is derived from Intel MultiProcessor Specification 1.4, B.4, but testing has shown
 /// that a second STARTUP IPI and setting the BIOS Reset Vector are no longer necessary.
@@ -559,10 +563,9 @@ pub fn boot_application_processors() {
 		// Set entry point
 		debug!(
 			"Set entry point for application processor to 0x{:x}",
-			arch::x86_64::kernel::start::_start as u64
+			_start as u64
 		);
-		*((SMP_BOOT_CODE_ADDRESS + SMP_BOOT_CODE_OFFSET_ENTRY).as_mut_ptr()) =
-			arch::x86_64::kernel::start::_start as u64;
+		*((SMP_BOOT_CODE_ADDRESS + SMP_BOOT_CODE_OFFSET_ENTRY).as_mut_ptr()) = _start as u64;
 		*((SMP_BOOT_CODE_ADDRESS + SMP_BOOT_CODE_OFFSET_BOOTINFO).as_mut_ptr()) = BOOT_INFO as u64;
 	}
 

src/arch/x86_64/kernel/gdt.rs

@@ -131,6 +131,7 @@ pub fn add_current_core() {
 }
 
 #[inline(never)]
+#[no_mangle]
 pub fn set_current_kernel_stack() {
 	core_scheduler().set_current_kernel_stack();
 }

src/arch/x86_64/kernel/mod.rs

@@ -25,9 +25,6 @@ pub mod scheduler;
 pub mod serial;
 #[cfg(not(test))]
 mod smp_boot_code;
-#[cfg(not(test))]
-mod start;
-pub mod switch;
 pub mod systemtime;
 #[cfg(feature = "vga")]
 mod vga;
@@ -49,7 +46,12 @@ use core::convert::TryInto;
 #[cfg(feature = "newlib")]
 use core::slice;
 use core::{intrinsics, ptr};
-use x86::controlregs::{cr0, cr4};
+use x86::controlregs::{cr0, cr0_write, cr4, Cr0};
+
+#[cfg(not(test))]
+global_asm!(include_str!("start.s"));
+#[cfg(not(test))]
+global_asm!(include_str!("switch.s"));
 
 const SERIAL_PORT_BAUDRATE: u32 = 115_200;
 
@@ -403,3 +405,21 @@ pub fn print_statistics() {
 		}
 	}
 }
+
+#[cfg(not(test))]
+#[inline(never)]
+#[no_mangle]
+unsafe fn pre_init(boot_info: &'static mut BootInfo) -> ! {
+	// Enable caching
+	let mut cr0 = cr0();
+	cr0.remove(Cr0::CR0_CACHE_DISABLE | Cr0::CR0_NOT_WRITE_THROUGH);
+	cr0_write(cr0);
+
+	BOOT_INFO = boot_info as *mut BootInfo;
+
+	if boot_info.cpu_online == 0 {
+		crate::boot_processor_main()
+	} else {
+		crate::application_processor_main()
+	}
+}

src/arch/x86_64/kernel/scheduler.rs

@@ -327,14 +327,17 @@ impl Clone for TaskTLS {
 }
 
 #[cfg(test)]
-extern "C" fn task_entry(func: extern "C" fn(usize), arg: usize) {}
+extern "C" fn task_start(func: extern "C" fn(usize), arg: usize, user_stack: u64) {}
 
 #[cfg(not(test))]
+extern "C" {
+	fn task_start(func: extern "C" fn(usize), arg: usize, user_stack: u64);
+}
+
 #[inline(never)]
-#[naked]
+#[no_mangle]
 extern "C" fn task_entry(func: extern "C" fn(usize), arg: usize) -> ! {
 	// Call the actual entry point of the task.
-	switch_to_user!();
 	func(arg);
 	switch_to_kernel!();
 
@@ -366,7 +369,7 @@ impl TaskFrame for Task {
 			if let Some(tls) = &self.tls {
 				(*state).fs = tls.get_fs().as_u64();
 			}
-			(*state).rip = task_entry as u64;
+			(*state).rip = task_start as u64;
 			(*state).rdi = func as u64;
 			(*state).rsi = arg as u64;
 
@@ -377,6 +380,9 @@ impl TaskFrame for Task {
 			self.last_stack_pointer = stack;
 			self.user_stack_pointer =
 				self.stacks.get_user_stack() + self.stacks.get_user_stack_size() - 0x10u64;
+
+			// rdx is required to intialize the stack
+			(*state).rdx = self.user_stack_pointer.as_u64() - mem::size_of::<u64>() as u64;
 		}
 	}
 }

src/arch/x86_64/kernel/start.s

@@ -0,0 +1,32 @@
+// Copyright (c) 2020 Stefan Lankes, RWTH Aachen University
+//
+// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
+// http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
+// http://opensource.org/licenses/MIT>, at your option. This file may not be
+// copied, modified, or distributed except according to those terms.
+
+.section .text
+.global _start
+.global task_start
+.extern pre_init
+.extern task_entry
+
+.align 16
+_start:
+	// initialize stack pointer
+	mov $0x7ff0,%rax
+	add 0x38(%rdi),%rax
+	mov %rax, %rsp
+	mov %rsp, %rbp
+
+	call pre_init
+
+l1:
+	jmp l1
+
+.align 16
+task_start:
+	mov %rdx, %rsp
+	sti
+	jmp task_entry
+	jmp l1