Make query_memory_map unsafe

Author: phil-opp

bios/stage-2/src/main.rs

@@ -97,7 +97,7 @@ fn start(disk_number: u16, partition_table_start: *const u8) -> ! {
     let kernel_len = load_file("kernel-x86_64", KERNEL_DST, &mut fs, &mut disk, disk_buffer);
     writeln!(screen::Writer, "kernel loaded at {KERNEL_DST:#p}").unwrap();
 
-    let memory_map = memory_map::query_memory_map().unwrap();
+    let memory_map = unsafe { memory_map::query_memory_map() }.unwrap();
     writeln!(screen::Writer, "{memory_map:x?}").unwrap();
 
     // TODO: load these from the kernel's config instead of hardcoding

bios/stage-2/src/memory_map.rs

@@ -14,7 +14,7 @@ static MEMORY_MAP: RacyCell<[E820MemoryRegion; 100]> = RacyCell::new(
 );
 
 /// use the INT 0x15, eax= 0xE820 BIOS function to get a memory map
-pub fn query_memory_map() -> Result<&'static mut [E820MemoryRegion], ()> {
+pub unsafe fn query_memory_map() -> Result<&'static mut [E820MemoryRegion], ()> {
     const SMAP: u32 = 0x534D4150;
 
     let memory_map = unsafe { MEMORY_MAP.get_mut() };