Struct page_table_entry::PageTableEntry

pub struct PageTableEntry(/* private fields */);

A page table entry, which is a u64 value under the hood.

It contains a the physical address of the Frame being mapped by this entry and the access bits (encoded PteFlags) that describes how it’s mapped, e.g., readable, writable, no exec, etc.

There isn’t and shouldn’t be any way to create/instantiate a new PageTableEntry directly. You can only obtain a reference to an PageTableEntry by going through a page table’s Table struct itself.

Implementations

impl PageTableEntry

pub fn is_unused(&self) -> bool

Returns true if this entry is unused, i.e., cleared/zeroed out.

pub fn zero(&mut self)

Zeroes out this entry, setting it as “unused”.

pub fn set_unmapped(&mut self) -> UnmapResult

Removes the mapping represented by this page table entry.

If the frame(s) pointed to by this entry were mapped exlusively, i.e., owned by this entry and not mapped anywhere else by any other entries, then this function returns those frames. This is useful because those returned frames can then be safely deallocated.

pub fn flags(&self) -> PteFlagsArch

Returns this PageTableEntry’s flags.

pub fn pointed_frame(&self) -> Option<Frame>

Returns the physical Frame pointed to (mapped by) this PageTableEntry. If this page table entry is not PRESENT, this returns None.

pub fn set_entry<P: PageSize>( &mut self, frame: AllocatedFrame<'_, P>, flags: PteFlagsArch )

Sets this PageTableEntry to map the given frame with the given flags.

This is the actual mapping action that informs the MMU of a new mapping.

Note: this performs no checks about the current value of this page table entry.

pub fn set_flags(&mut self, new_flags: PteFlagsArch)

Sets the flags components of this PageTableEntry to new_flags.

This does not modify the frame part of the page table entry.

pub fn value(&self) -> u64

Trait Implementations

impl FromBytes for PageTableEntry