Trait MappingBackend

Source

pub trait MappingBackend: Clone {
    type Addr: MemoryAddr;
    type Flags: Copy;
    type PageTable;

    // Required methods
    fn map(
        &self,
        start: Self::Addr,
        size: usize,
        flags: Self::Flags,
        page_table: &mut Self::PageTable,
    ) -> bool;
    fn unmap(
        &self,
        start: Self::Addr,
        size: usize,
        page_table: &mut Self::PageTable,
    ) -> bool;
    fn protect(
        &self,
        start: Self::Addr,
        size: usize,
        new_flags: Self::Flags,
        page_table: &mut Self::PageTable,
    ) -> bool;
    fn split(&mut self, align_diff: usize) -> Option<Self>;

    // Provided methods
    fn shrink_left(&mut self, _shrink_size: usize) { ... }
    fn shrink_right(&mut self, _shrink_size: usize) { ... }
}

Expand description

Underlying operations to do when manipulating mappings within the specific MemoryArea.

The backend can be different for different memory areas. e.g., for linear mappings, the target physical address is known when it is added to the page table. For lazy mappings, an empty mapping needs to be added to the page table to trigger a page fault.