Compile fix

.travis.yml

@@ -25,16 +25,3 @@ notifications:
 script:
 - RUST_TARGET_PATH=`pwd` xargo build --target x86_64-bootloader --release
 - objcopy -O binary -S target/x86_64-bootloader/release/bootloader bootimage.bin
-
-deploy:
-  provider: script
-  skip_cleanup: true
-  on:
-    repo: rust-osdev/bootloader
-    tags: true
-  script:
-    - |
-      if [[ "$TRAVIS_TAG" == v* ]]; then
-        echo "Deploy for $TRAVIS_TAG"
-        echo "UNIMPLEMENTED!"
-      fi

Cargo.toml

@@ -1,14 +1,16 @@
+cargo-features = ["publish-lockfile"]
+
 [package]
 name = "bootloader"
-version = "0.2.0-alpha-004"
+version = "0.2.0"
 authors = ["Philipp Oppermann <[email protected]>"]
 license = "MIT/Apache-2.0"
 description = "An experimental pure-Rust x86 bootloader."
+publish-lockfile = true
 
 [dependencies]
 xmas-elf = "0.6.2"
-# x86_64 = "0.2.0-alpha"
-x86_64 = { git = "https://github.com/nebulet/x86_64" }
+x86_64 = "0.2.7"
 usize_conversions = "0.2.0"
 # os_bootinfo = "0.2.0"
 os_bootinfo = { git = "https://github.com/nebulet/os_bootinfo" }

src/boot.s

@@ -12,7 +12,8 @@ _start:
     mov fs, ax
     mov gs, ax
 
-    # TODO explain
+    # clear the direction flag (e.g. go forward in memory when using
+    # instructions like lodsb)
     cld
 
 
@@ -29,6 +30,7 @@ enable_a20:
     out 0x92, al
 
 enter_protected_mode:
+    # clear interrupts
     cli
     push ds
     push es
@@ -118,6 +120,9 @@ println:
 print:
     cld
 print_loop:
+    # note: if direction flag is set (via std)
+    # this will DECREMENT the ptr, effectively
+    # reading/printing in reverse.
     lodsb al, BYTE PTR [esi]
     test al, al
     jz print_done

src/lib.rs

@@ -0,0 +1,27 @@
+#![no_std]
+
+extern crate os_bootinfo;
+
+pub mod bootinfo {
+    pub use os_bootinfo::*;
+}
+
+/// Defines the entry point function.
+///
+/// The function must have the signature `fn(&'static BootInfo) -> !`.
+///
+/// This macro just creates a function named `_start`, which the linker will use as the entry
+/// point. The advantage of using this macro instead of providing an own `_start` function is
+/// that the macro ensures that the function and argument types are correct.
+#[macro_export]
+macro_rules! entry_point {
+    ($path:path) => {
+        #[export_name = "_start"]
+        pub extern "C" fn __impl_start(boot_info: &'static $crate::bootinfo::BootInfo) -> ! {
+            // validate the signature of the program entry point
+            let f: fn(&'static $crate::bootinfo::BootInfo) -> ! = $path;
+
+            f(boot_info)
+        }
+    };
+}

src/main.rs

@@ -1,13 +1,10 @@
 #![feature(lang_items)]
 #![feature(global_asm)]
-#![feature(iterator_step_by)]
 #![feature(try_from)]
 #![feature(step_trait)]
 #![feature(asm)]
 #![feature(nll)]
-#![feature(pointer_methods)]
 #![feature(const_fn)]
-#![feature(nll)]
 #![feature(panic_implementation)]
 #![no_std]
 #![no_main]
@@ -174,9 +171,7 @@ pub extern "C" fn load_elf(
     let kernel_end_page: Page<Size2MiB> =
         Page::containing_address(kernel_start.virt() + kernel_size - 1u64);
     for page in Page::range_inclusive(kernel_start_page, kernel_end_page) {
-        rec_page_table
-            .unmap(page)
-            .expect("dealloc error").1.flush();
+        rec_page_table.unmap(page).expect("dealloc error").1.flush();
     }
 
     // Map kernel segments.
@@ -252,9 +247,7 @@ fn enable_write_protect_bit() {
 #[no_mangle]
 pub extern "C" fn panic(info: &PanicInfo) -> ! {
     use core::fmt::Write;
-
-    let _ = write!(printer::Printer, "{}", info);
-
+    write!(printer::Printer, "{}", info).unwrap();
     loop {}
 }
 

src/page_table.rs

@@ -1,7 +1,7 @@
 use fixedvec::FixedVec;
 use frame_allocator::FrameAllocator;
 use os_bootinfo::MemoryRegionType;
-use x86_64::structures::paging::{MapToError, RecursivePageTable, UnmapError};
+use x86_64::structures::paging::{self, MapToError, RecursivePageTable, UnmapError};
 use x86_64::structures::paging::{Mapper, MapperFlush, Page, PageSize, PageTableFlags, PhysFrame, Size4KiB};
 use x86_64::{align_up, PhysAddr, VirtAddr};
 use xmas_elf::program::{self, ProgramHeader64};
@@ -158,5 +158,13 @@ where
     S: PageSize,
     RecursivePageTable<'a>: Mapper<S>,
 {
-    page_table.map_to(page, phys_frame, flags, frame_allocator)
+    struct PageTableAllocator<'a, 'b: 'a>(&'a mut FrameAllocator<'b>);
+
+    impl<'a, 'b> paging::FrameAllocator<Size4KiB> for PageTableAllocator<'a, 'b> {
+        fn alloc(&mut self) -> Option<PhysFrame<Size4KiB>> {
+            self.0.allocate_frame(MemoryRegionType::PageTable)
+        }
+    }
+
+    page_table.map_to(page, phys_frame, flags, &mut PageTableAllocator(frame_allocator))
 }

src/second_stage.s

@@ -10,6 +10,18 @@ second_stage:
     lea si, second_stage_start_str
     call println
 
+set_target_operating_mode:
+    # Some BIOSs assume the processor will only operate in Legacy Mode. We change the Target
+    # Operating Mode to "Long Mode Target Only", so the firmware expects each CPU to enter Long Mode
+    # once and then stay in it. This allows the firmware to enable mode-specifc optimizations.
+    # We save the flags, because CF is set if the callback is not supported (in which case, this is
+    # a NOP)
+    pushf
+    mov ax, 0xec00
+    mov bl, 0x2
+    int 0x15
+    popf
+
 load_kernel_from_disk:
     # start of memory buffer
     lea eax, _kernel_buffer
@@ -50,7 +62,11 @@ load_next_kernel_block_from_disk:
     push ecx
     push esi
     mov ecx, 512 / 4
+    # move with zero extension
+    # because we are moving a word ptr
+    # to esi, a 32-bit register.
     movzx esi, word ptr [dap_buffer_addr]
+    # move from esi to edi ecx times.
     rep movsd [edi], [esi]
     pop esi
     pop ecx
@@ -71,13 +87,7 @@ check_cpu:
     call check_cpuid
     call check_long_mode
 
-disable_irqs:
-    mov al, 0xFF     # Out 0xFF to 0xA1 and 0x21 to disable all IRQs.
-    out 0xA1, al
-    out 0x21, al
-
-    nop
-    nop
+    cli                   # disable interrupts
 
     lidt zero_idt         # Load a zero length IDT so that any NMI causes a triple fault.
 
@@ -250,7 +260,7 @@ gdt_64_pointer:
 
 long_mode:
     # call load_elf with kernel start address, size, and memory map as arguments
-    movabs rdi, 0x400000
+    movabs rdi, 0x400000 # move absolute 64-bit to register
     mov rsi, _kib_kernel_size
     lea rdx, _memory_map
     movzx rcx, word ptr mmap_ent