Cleanup PML4 entries, pass correct cpu ID to trampoline

arch/x86_64/src/acpi/mod.rs

@@ -66,12 +66,14 @@ pub fn init_sdt(sdt: &'static Sdt, active_table: &mut ActivePageTable) {
                         let stack_end = allocate_frame().expect("no more frames in acpi stack_end").start_address().get() + 4096;
 
                         let ap_ready = TRAMPOLINE as *mut u64;
-                        let ap_stack_start = unsafe { ap_ready.offset(1) };
+                        let ap_cpu_id = unsafe { ap_ready.offset(1) };
-                        let ap_stack_end = unsafe { ap_ready.offset(2) };
+                        let ap_stack_start = unsafe { ap_ready.offset(2) };
-                        let ap_code = unsafe { ap_ready.offset(3) };
+                        let ap_stack_end = unsafe { ap_ready.offset(3) };
+                        let ap_code = unsafe { ap_ready.offset(4) };
 
                         // Set the ap_ready to 0, volatile
                         unsafe { atomic_store(ap_ready, 0) };
+                        unsafe { atomic_store(ap_cpu_id, ap_local_apic.id as u64) };
                         unsafe { atomic_store(ap_stack_start, stack_start as u64) };
                         unsafe { atomic_store(ap_stack_end, stack_end as u64) };
                         unsafe { atomic_store(ap_code, kstart_ap as u64) };

arch/x86_64/src/lib.rs

@@ -20,20 +20,29 @@ extern crate spin;
 pub extern crate x86;
 
 // Because the memory map is so important to not be aliased, it is defined here, in one place
-/// Offset of recursive paging
+// The lower 256 PML4 entries are reserved for userspace
-pub const RECURSIVE_PAGE_OFFSET: usize = 0xffff_ff80_0000_0000;
+// Each PML4 entry references up to 512 GB of memory
-/// Offset of kernel
+// The upper 256 are reserved for the kernel
-pub const KERNEL_OFFSET: usize = 0xffff_ff00_0000_0000;
+    /// The size of a single PML4
-/// Offset to memory allocation bitmap
+    pub const PML4_SIZE: usize = 0x0000_0080_0000_0000;
-pub const BITMAP_OFFSET: usize = 0xffff_fe80_0000_0000;
+
-/// Offset to kernel heap
+    /// Offset of recursive paging
-pub const HEAP_OFFSET: usize = 0xffff_fe00_0000_0000;
+    pub const RECURSIVE_PAGE_OFFSET: usize = (-(PML4_SIZE as isize)) as usize;
-/// Size of heap
+
-pub const HEAP_SIZE: usize = 64 * 1024 * 1024; // 64 MB
+    /// Offset of kernel
-/// Offset to user heap
+    pub const KERNEL_OFFSET: usize = RECURSIVE_PAGE_OFFSET - PML4_SIZE;
-pub const USER_HEAP_OFFSET: usize = 0x0000_0080_0000_0000;
+
-/// Size of user heap
+    /// Offset to kernel heap
-pub const USER_HEAP_SIZE: usize = 64 * 1024 * 1024; // 64 MB
+    pub const KERNEL_HEAP_OFFSET: usize = KERNEL_OFFSET - PML4_SIZE;
+    /// Size of kernel heap
+    pub const KERNEL_HEAP_SIZE: usize = 64 * 1024 * 1024; // 64 MB
+
+    /// Offset to kernel percpu variables
+    pub const KERNEL_PERCPU_OFFSET: usize = KERNEL_HEAP_OFFSET - PML4_SIZE;
+
+    /// Offset to user heap
+    pub const USER_HEAP_OFFSET: usize = PML4_SIZE;
+
 
 /// Print to console
 #[macro_export]

arch/x86_64/src/memory/bitmap_allocator.rs

@@ -1,39 +0,0 @@
-use super::AreaFrameAllocator;
-
-const BITMAP_RESERVED: usize = 0;
-const BITMAP_FREE: usize = 1;
-const BITMAP_USED: usize = 2;
-
-pub struct BitmapAllocator {
-    bitmap: &'static mut [u8]
-}
-
-impl BitmapAllocator {
-    pub fn new(area_frame_allocator: AreaFrameAllocator) -> BitmapAllocator {
-        BitmapAllocator {
-            bitmap: &mut []
-        }
-    }
-}
-
-impl FrameAllocator for BitmapAllocator {
-    fn allocate_frame(&mut self) -> Option<Frame> {
-        let mut i = 0;
-        while i < self.bitmap.len() {
-            if self.bitmap[i] == BITMAP_FREE {
-                self.bitmap[i] = BITMAP_USED;
-                return Some(Frame::containing_address(PhysicalAddress::new(i * 4096)));
-            }
-        }
-        None
-    }
-
-    fn deallocate_frame(&mut self, frame: Frame) {
-        let i = frame.starting_address().get()/4096;
-        if i < self.bitmap.len() && self.bitmap[i] == BITMAP_USED {
-            self.bitmap[i] = BITMAP_FREE;
-        } else {
-            panic!("BitmapAllocator::deallocate_frame: unowned frame {:?}", frame);
-        }
-    }
-}

arch/x86_64/src/paging/mod.rs

@@ -25,7 +25,7 @@ pub const PAGE_SIZE: usize = 4096;
 /// Initialize paging
 ///
 /// Returns page table and thread control block offset
-pub unsafe fn init(stack_start: usize, stack_end: usize) -> (ActivePageTable, usize) {
+pub unsafe fn init(cpu_id: usize, stack_start: usize, stack_end: usize) -> (ActivePageTable, usize) {
     extern {
         /// The starting byte of the text (code) data segment.
         static mut __text_start: u8;

arch/x86_64/src/start.rs

@@ -26,7 +26,6 @@ static mut TBSS_TEST_ZERO: usize = 0;
 #[thread_local]
 static mut TDATA_TEST_NONZERO: usize = 0xFFFFFFFFFFFFFFFF;
 
-static AP_COUNT: AtomicUsize = ATOMIC_USIZE_INIT;
 pub static AP_READY: AtomicBool = ATOMIC_BOOL_INIT;
 static BSP_READY: AtomicBool = ATOMIC_BOOL_INIT;
 static HEAP_TABLE: AtomicUsize = ATOMIC_USIZE_INIT;
@@ -73,7 +72,7 @@ pub unsafe extern fn kstart() -> ! {
         let stack_end = 0x0009F000;
 
         // Initialize paging
-        let (mut active_table, tcb_offset) = paging::init(stack_start, stack_end);
+        let (mut active_table, tcb_offset) = paging::init(0, stack_start, stack_end);
 
         // Set up GDT
         gdt::init(tcb_offset, stack_end);
@@ -92,7 +91,6 @@ pub unsafe extern fn kstart() -> ! {
         }
 
         // Reset AP variables
-        AP_COUNT.store(0, Ordering::SeqCst);
         AP_READY.store(false, Ordering::SeqCst);
         BSP_READY.store(false, Ordering::SeqCst);
         HEAP_TABLE.store(0, Ordering::SeqCst);
@@ -100,14 +98,14 @@ pub unsafe extern fn kstart() -> ! {
         // Map heap
         {
             // Map heap pages
-            let heap_start_page = Page::containing_address(VirtualAddress::new(::HEAP_OFFSET));
+            let heap_start_page = Page::containing_address(VirtualAddress::new(::KERNEL_HEAP_OFFSET));
-            let heap_end_page = Page::containing_address(VirtualAddress::new(::HEAP_OFFSET + ::HEAP_SIZE-1));
+            let heap_end_page = Page::containing_address(VirtualAddress::new(::KERNEL_HEAP_OFFSET + ::KERNEL_HEAP_SIZE-1));
             for page in Page::range_inclusive(heap_start_page, heap_end_page) {
                 active_table.map(page, entry::WRITABLE | entry::NO_EXECUTE);
             }
 
             // Init the allocator
-            allocator::init(::HEAP_OFFSET, ::HEAP_SIZE);
+            allocator::init(::KERNEL_HEAP_OFFSET, ::KERNEL_HEAP_SIZE);
 
             // Send heap page table to APs
             let index = heap_start_page.p4_index();
@@ -136,13 +134,13 @@ pub unsafe extern fn kstart() -> ! {
 }
 
 /// Entry to rust for an AP
-pub unsafe extern fn kstart_ap(stack_start: usize, stack_end: usize) -> ! {
+pub unsafe extern fn kstart_ap(cpu_id: usize, stack_start: usize, stack_end: usize) -> ! {
     {
         assert_eq!(BSS_TEST_ZERO, 0);
         assert_eq!(DATA_TEST_NONZERO, 0xFFFFFFFFFFFFFFFF);
 
         // Initialize paging
-        let (mut active_table, tcb_offset) = paging::init(stack_start, stack_end);
+        let (mut active_table, tcb_offset) = paging::init(cpu_id, stack_start, stack_end);
 
         // Set up GDT for AP
         gdt::init_ap(tcb_offset, stack_end);
@@ -162,13 +160,12 @@ pub unsafe extern fn kstart_ap(stack_start: usize, stack_end: usize) -> ! {
 
         // Copy heap PML4
         {
-            let page = Page::containing_address(VirtualAddress::new(::HEAP_OFFSET));
-
             while HEAP_TABLE.load(Ordering::SeqCst) == 0 {
                 interrupt::pause();
             }
             let frame = Frame::containing_address(PhysicalAddress::new(HEAP_TABLE.load(Ordering::SeqCst)));
 
+            let page = Page::containing_address(VirtualAddress::new(::KERNEL_HEAP_OFFSET));
             let p4 = active_table.p4_mut();
             let entry = &mut p4[page.p4_index()];
             assert!(entry.is_unused());
@@ -181,13 +178,11 @@ pub unsafe extern fn kstart_ap(stack_start: usize, stack_end: usize) -> ! {
         AP_READY.store(true, Ordering::SeqCst);
     }
 
-    let ap_number = AP_COUNT.fetch_add(1, Ordering::SeqCst);
-
     while ! BSP_READY.load(Ordering::SeqCst) {
         interrupt::pause();
     }
 
-    kmain_ap(ap_number);
+    kmain_ap(cpu_id);
 }
 
 pub unsafe fn usermode(ip: usize, sp: usize) -> ! {

bootloader/x86_64/startup-x86_64.asm

@@ -1,5 +1,6 @@
 trampoline:
     .ready: dq 0
+    .cpu_id: dq 0
     .stack_start: dq 0
     .stack_end: dq 0
     .code: dq 0
@@ -131,11 +132,11 @@ long_mode_ap:
     mov gs, rax
     mov ss, rax
 
+    mov rdi, [trampoline.cpu_id]
+    mov rsi, [trampoline.stack_start]
+    mov rdx, [trampoline.stack_end]
 
-    mov rdi, [trampoline.stack_start]
+    lea rsp, [rdx - 256]
-    mov rsi, [trampoline.stack_end]
-
-    lea rsp, [rsi - 16]
 
     mov qword [trampoline.ready], 1
     mov rax, [trampoline.code]