Struct x86_64::structures::paging::RecursivePageTable

pub struct RecursivePageTable<'a> { /* fields omitted */ }

A recursive page table is a last level page table with an entry mapped to the table itself.

This recursive mapping allows accessing all page tables in the hierarchy:

• To access the level 4 page table, we “loop“ (i.e. follow the recursively mapped entry) four times.
• To access a level 3 page table, we “loop” three times and then use the level 4 index.
• To access a level 2 page table, we “loop” two times, then use the level 4 index, then the level 3 index.
• To access a level 1 page table, we “loop” once, then use the level 4 index, then the level 3 index, then the level 2 index.

This struct implements the Mapper trait.

Methods

impl<'a> RecursivePageTable<'a>

pub fn new(table: &'a mut PageTable) -> Result<Self, NotRecursivelyMapped>

Creates a new RecursivePageTable from the passed level 4 PageTable.

The page table must be recursively mapped, that means:

• The page table must have one recursive entry, i.e. an entry that points to the table itself.
  • The reference must use that “loop”, i.e. be of the form 0o_xxx_xxx_xxx_xxx_0000 where xxx is the recursive entry.
• The page table must be active, i.e. the CR3 register must contain its physical address.

Otherwise Err(NotRecursivelyMapped) is returned.

pub unsafe fn new_unchecked(     table: &'a mut PageTable,     recursive_index: u9 ) -> Self

Creates a new RecursivePageTable without performing any checks.

The recursive_index parameter must be the index of the recursively mapped entry.

Trait Implementations

impl<'a> Mapper<Size1GiB> for RecursivePageTable<'a>

fn map_to<A>(     &mut self,     page: Page<Size1GiB>,     frame: PhysFrame<Size1GiB>,     flags: PageTableFlags,     allocator: &mut A ) -> Result<MapperFlush<Size1GiB>, MapToError> where     A: FrameAllocator<Size4KiB>,

Creates a new mapping in the page table.

fn unmap(     &mut self,     page: Page<Size1GiB> ) -> Result<(PhysFrame<Size1GiB>, MapperFlush<Size1GiB>), UnmapError>

Removes a mapping from the page table and returns the frame that used to be mapped.

fn update_flags(     &mut self,     page: Page<Size1GiB>,     flags: PageTableFlags ) -> Result<MapperFlush<Size1GiB>, FlagUpdateError>

Updates the flags of an existing mapping.

fn translate_page(&self, page: Page<Size1GiB>) -> Option<PhysFrame<Size1GiB>>

Return the frame that the specified page is mapped to.

fn identity_map<A>(     &mut self,     frame: PhysFrame<S>,     flags: PageTableFlags,     allocator: &mut A ) -> Result<MapperFlush<S>, MapToError> where     A: FrameAllocator<Size4KiB>,     S: PageSize,     Self: Mapper<S>,

Maps the given frame to the virtual page with the same address.

impl<'a> Mapper<Size2MiB> for RecursivePageTable<'a>

fn map_to<A>(     &mut self,     page: Page<Size2MiB>,     frame: PhysFrame<Size2MiB>,     flags: PageTableFlags,     allocator: &mut A ) -> Result<MapperFlush<Size2MiB>, MapToError> where     A: FrameAllocator<Size4KiB>,

Creates a new mapping in the page table.

fn unmap(     &mut self,     page: Page<Size2MiB> ) -> Result<(PhysFrame<Size2MiB>, MapperFlush<Size2MiB>), UnmapError>

Removes a mapping from the page table and returns the frame that used to be mapped.

fn update_flags(     &mut self,     page: Page<Size2MiB>,     flags: PageTableFlags ) -> Result<MapperFlush<Size2MiB>, FlagUpdateError>

Updates the flags of an existing mapping.

fn translate_page(&self, page: Page<Size2MiB>) -> Option<PhysFrame<Size2MiB>>

Return the frame that the specified page is mapped to.

fn identity_map<A>(     &mut self,     frame: PhysFrame<S>,     flags: PageTableFlags,     allocator: &mut A ) -> Result<MapperFlush<S>, MapToError> where     A: FrameAllocator<Size4KiB>,     S: PageSize,     Self: Mapper<S>,

Maps the given frame to the virtual page with the same address.

impl<'a> Mapper<Size4KiB> for RecursivePageTable<'a>

fn map_to<A>(     &mut self,     page: Page<Size4KiB>,     frame: PhysFrame<Size4KiB>,     flags: PageTableFlags,     allocator: &mut A ) -> Result<MapperFlush<Size4KiB>, MapToError> where     A: FrameAllocator<Size4KiB>,

Creates a new mapping in the page table.

fn unmap(     &mut self,     page: Page<Size4KiB> ) -> Result<(PhysFrame<Size4KiB>, MapperFlush<Size4KiB>), UnmapError>

Removes a mapping from the page table and returns the frame that used to be mapped.

fn update_flags(     &mut self,     page: Page<Size4KiB>,     flags: PageTableFlags ) -> Result<MapperFlush<Size4KiB>, FlagUpdateError>

Updates the flags of an existing mapping.

fn translate_page(&self, page: Page<Size4KiB>) -> Option<PhysFrame<Size4KiB>>

Return the frame that the specified page is mapped to.

fn identity_map<A>(     &mut self,     frame: PhysFrame<S>,     flags: PageTableFlags,     allocator: &mut A ) -> Result<MapperFlush<S>, MapToError> where     A: FrameAllocator<Size4KiB>,     S: PageSize,     Self: Mapper<S>,

Maps the given frame to the virtual page with the same address.