Struct page_table_entry::UnmappedFrames

pub struct UnmappedFrames(_);

A range of frames that have been unmapped from a PageTableEntry that previously mapped that frame exclusively (i.e., “owned it”).

These UnmappedFrames can be converted into UnmappedAllocatedFrames and then safely deallocated within the frame_allocator.

See the PageTableEntry::set_unmapped() function.

Methods from Deref<Target = FrameRange>

pub fn start_address(&self) -> PhysicalAddress

Returns the [PhysicalAddress] of the starting [Frame] in this FrameRange.

pub fn size_in_frames(&self) -> usize

Returns the number of [Frame]s covered by this iterator.

Use this instead of Iterator::count() method. This is instant, because it doesn’t need to iterate over each entry, unlike normal iterators.

pub fn size_in_bytes(&self) -> usize

Returns the size of this range in number of bytes.

pub fn contains_address(&self, addr: PhysicalAddress) -> bool

Returns true if this FrameRange contains the given [PhysicalAddress].

pub fn offset_of_address(&self, addr: PhysicalAddress) -> Option<usize>

Returns the offset of the given [PhysicalAddress] within this FrameRange, i.e., addr - self.start_address().

If the given addr is not covered by this range of [Frame]s, this returns None.

Examples

If the range covers addresses 0x2000 to 0x4000, then offset_of_address(0x3500) would return Some(0x1500).

pub fn address_at_offset(&self, offset: usize) -> Option<PhysicalAddress>

Returns the [PhysicalAddress] at the given offset into this FrameRangewithin this FrameRange, i.e., addr - self.start_address().

If the given offset is not within this range of [Frame]s, this returns None.

Examples

If the range covers addresses 0x2000 to 0x4000, then address_at_offset(0x1500) would return Some(0x3500).

pub fn to_extended(&self, to_include: Frame) -> FrameRange

Returns a new separate FrameRange that is extended to include the given [Frame].

pub fn overlap(&self, other: &FrameRange) -> Option<FrameRange>

Returns an inclusive FrameRange representing the [Frame]s that overlap across this FrameRange and the given other FrameRange.

If there is no overlap between the two ranges, None is returned.

Methods from Deref<Target = RangeInclusive<Frame>>

pub fn start(&self) -> &Idx

Returns the lower bound of the range (inclusive).

When using an inclusive range for iteration, the values of start() and end() are unspecified after the iteration ended. To determine whether the inclusive range is empty, use the is_empty() method instead of comparing start() > end().

Note: the value returned by this method is unspecified after the range has been iterated to exhaustion.

Examples

assert_eq!((3..=5).start(), &3);

pub fn end(&self) -> &Idx

Returns the upper bound of the range (inclusive).

When using an inclusive range for iteration, the values of start() and end() are unspecified after the iteration ended. To determine whether the inclusive range is empty, use the is_empty() method instead of comparing start() > end().

Note: the value returned by this method is unspecified after the range has been iterated to exhaustion.

Examples

assert_eq!((3..=5).end(), &5);

pub fn contains<U>(&self, item: &U) -> boolwhere
    Idx: PartialOrd<U>,
    U: PartialOrd<Idx> + ?Sized,

Returns true if item is contained in the range.

Examples

assert!(!(3..=5).contains(&2));
assert!( (3..=5).contains(&3));
assert!( (3..=5).contains(&4));
assert!( (3..=5).contains(&5));
assert!(!(3..=5).contains(&6));

assert!( (3..=3).contains(&3));
assert!(!(3..=2).contains(&3));

assert!( (0.0..=1.0).contains(&1.0));
assert!(!(0.0..=1.0).contains(&f32::NAN));
assert!(!(0.0..=f32::NAN).contains(&0.0));
assert!(!(f32::NAN..=1.0).contains(&1.0));

This method always returns false after iteration has finished:

let mut r = 3..=5;
assert!(r.contains(&3) && r.contains(&5));
for _ in r.by_ref() {}
// Precise field values are unspecified here
assert!(!r.contains(&3) && !r.contains(&5));

pub fn is_empty(&self) -> bool

Returns true if the range contains no items.

Examples

assert!(!(3..=5).is_empty());
assert!(!(3..=3).is_empty());
assert!( (3..=2).is_empty());

The range is empty if either side is incomparable:

assert!(!(3.0..=5.0).is_empty());
assert!( (3.0..=f32::NAN).is_empty());
assert!( (f32::NAN..=5.0).is_empty());

This method returns true after iteration has finished:

let mut r = 3..=5;
for _ in r.by_ref() {}
// Precise field values are unspecified here
assert!(r.is_empty());

Trait Implementations

impl Deref for UnmappedFrames

type Target = FrameRange

The resulting type after dereferencing.

fn deref(&self) -> &FrameRange

Dereferences the value.