Struct PageBuffer 

pub struct PageBuffer<const PAGES: usize> { /* private fields */ }

PAGES pages of PAGE_BYTES bytes, word aligned and contiguous.

Pair it with a crate::PagePool of the same capacity: the pool decides which pages belong to which allocation, the buffer owns the bytes. The all-zero image means a static buffer stays in .bss rather than the executable.

A byte view borrows the buffer, so it cannot outlive it, but it describes its run only until the pool compacts or the run is freed and reused: re-resolve through crate::Residency::try_run each use unless the entry is pinned.

Implementations

impl<const PAGES: usize> PageBuffer<PAGES>

pub const fn new() -> Self

A zero-filled buffer.

pub const fn page_count(&self) -> usize

Number of pages.

pub fn bytes(&self, run: PageRun, len: usize) -> Option<&[u8]>

The first len bytes of run, or None when the run is outside the buffer or shorter than len.

pub fn bytes_mut(&mut self, run: PageRun, len: usize) -> Option<&mut [u8]>

Mutable form of PageBuffer::bytes.

pub fn write(&mut self, run: PageRun, offset: usize, data: &[u8]) -> bool

Copy data to offset bytes into run. false when it does not fit.

pub fn move_pages(&mut self, from: PageRun, to_page: u32) -> bool

Move from to start at to_page (a memmove: the ranges may overlap). The owner calls this for each crate::PagePool::compact_step. false when either range is outside the buffer.

pub fn page_address(&mut self, page: u32) -> Option<*mut u8>

Address of the first byte of page, for a transport that lands sectors in place. None past the end.

Trait Implementations

impl<const PAGES: usize> Default for PageBuffer<PAGES>

fn default() -> Self

Returns the “default value” for a type.