virtiod: split into virtio-core and virtiod

Signed-off-by: Anhad Singh <andypython@protonmail.com>

virtio-core/src/utils.rs

@@ -0,0 +1,65 @@
+use core::cell::UnsafeCell;
+use core::marker::PhantomData;
+
+#[derive(Debug)]
+#[repr(C)]
+pub struct VolatileCell<T> {
+    value: UnsafeCell<T>,
+}
+
+impl<T: Copy> VolatileCell<T> {
+    #[inline]
+    pub fn new(value: T) -> Self {
+        Self {
+            value: UnsafeCell::new(value),
+        }
+    }
+
+    /// Returns a copy of the contained value.
+    #[inline]
+    pub fn get(&self) -> T {
+        unsafe { core::ptr::read_volatile(self.value.get()) }
+    }
+
+    /// Sets the contained value.
+    #[inline]
+    pub fn set(&mut self, value: T) {
+        unsafe { core::ptr::write_volatile(self.value.get(), value) }
+    }
+}
+
+unsafe impl<T> Sync for VolatileCell<T> {}
+
+#[repr(C)]
+pub struct IncompleteArrayField<T>(PhantomData<T>, [T; 0]);
+
+impl<T> IncompleteArrayField<T> {
+    #[inline]
+    pub const fn new() -> Self {
+        IncompleteArrayField(PhantomData, [])
+    }
+
+    #[inline]
+    pub unsafe fn as_slice(&self, len: usize) -> &[T] {
+        core::slice::from_raw_parts(self.as_ptr(), len)
+    }
+
+    #[inline]
+    pub unsafe fn as_mut_slice(&mut self, len: usize) -> &mut [T] {
+        core::slice::from_raw_parts_mut(self.as_mut_ptr(), len)
+    }
+
+    #[inline]
+    pub unsafe fn as_ptr(&self) -> *const T {
+        self as *const _ as *const T
+    }
+
+    #[inline]
+    pub unsafe fn as_mut_ptr(&mut self) -> *mut T {
+        self as *mut _ as *mut T
+    }
+}
+
+pub const fn align(val: usize, align: usize) -> usize {
+    (val + align) & !align
+}