Initial documentation

kernel/src/sync.rs

@@ -1,22 +1,31 @@
+//! Synchronization facilities module
+
 use core::ops::{Deref, DerefMut};
 use core::cell::UnsafeCell;
 
+/// Dummy lock implementation, does not do any locking.
+///
+/// Only safe to use before I implement context switching or
+/// interrupts are enabled.
 #[repr(transparent)]
 pub struct NullLock<T: ?Sized> {
     value: UnsafeCell<T>
 }
 
+/// Dummy lock guard for [NullLock].
 #[repr(transparent)]
 pub struct NullLockGuard<'a, T: ?Sized> {
     value: &'a mut T
 }
 
 impl<T> NullLock<T> {
+    /// Constructs a new instance of the lock, wrapping `value`
     #[inline(always)]
     pub const fn new(value: T) -> Self {
         Self { value: UnsafeCell::new(value) }
     }
 
+    /// Returns [NullLockGuard] for this lock
     #[inline(always)]
     pub fn lock(&self) -> NullLockGuard<T> {
         NullLockGuard { value: unsafe { &mut *self.value.get() } }