Struct vm_memory::volatile_memory::VolatileRef

pub struct VolatileRef<'a, T, B = ()> { /* private fields */ }

A memory location that supports volatile access to an instance of T.

Examples

let mut v = 5u32;
let v_ref = unsafe { VolatileRef::new(&mut v as *mut u32 as *mut u8) };

assert_eq!(v, 5);
assert_eq!(v_ref.load(), 5);
v_ref.store(500);
assert_eq!(v, 500);

Implementations

impl<'a, T> VolatileRef<'a, T, ()>

where T: ByteValued,

pub unsafe fn new(addr: *mut u8) -> Self

Creates a VolatileRef to an instance of T.

Safety

To use this safely, the caller must guarantee that the memory at addr is big enough for a T and is available for the duration of the lifetime of the new VolatileRef. The caller must also guarantee that all other users of the given chunk of memory are using volatile accesses.

impl<'a, T, B> VolatileRef<'a, T, B>

where T: ByteValued, B: BitmapSlice,

pub unsafe fn with_bitmap(addr: *mut u8, bitmap: B) -> Self

Creates a VolatileRef to an instance of T, using the provided bitmap object for dirty page tracking.

Safety

To use this safely, the caller must guarantee that the memory at addr is big enough for a T and is available for the duration of the lifetime of the new VolatileRef. The caller must also guarantee that all other users of the given chunk of memory are using volatile accesses.

pub fn as_ptr(&self) -> *mut u8

Returns a pointer to the underlying memory. Mutable accesses performed using the resulting pointer are not automatically accounted for by the dirty bitmap tracking functionality.

pub fn len(&self) -> usize

Gets the size of the referenced type T.

Examples

let v_ref = unsafe { VolatileRef::<u32>::new(0 as *mut _) };
assert_eq!(v_ref.len(), size_of::<u32>() as usize);

pub fn bitmap(&self) -> &B

Borrows the inner BitmapSlice.

pub fn store(&self, v: T)

Does a volatile write of the value v to the address of this ref.

pub fn load(&self) -> T

Does a volatile read of the value at the address of this ref.

pub fn to_slice(&self) -> VolatileSlice<'a, B>

Converts this to a VolatileSlice with the same size and address.

Trait Implementations

impl<'a, T: Clone, B: Clone> Clone for VolatileRef<'a, T, B>

fn clone(&self) -> VolatileRef<'a, T, B>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a, T: Debug, B: Debug> Debug for VolatileRef<'a, T, B>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, T: Copy, B: Copy> Copy for VolatileRef<'a, T, B>