Trait mmtk::util::heap::layout::mmapper::Mmapper

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pub trait Mmapper: Sync {
    // Required methods
    fn eagerly_mmap_all_spaces(&self, space_map: &[Address]);
    fn mark_as_mapped(&self, start: Address, bytes: usize);
    fn quarantine_address_range(
        &self,
        start: Address,
        pages: usize,
        strategy: MmapStrategy
    ) -> Result<()>;
    fn ensure_mapped(
        &self,
        start: Address,
        pages: usize,
        strategy: MmapStrategy
    ) -> Result<()>;
    fn is_mapped_address(&self, addr: Address) -> bool;
    fn protect(&self, start: Address, pages: usize);
}

Expand description

Generic mmap and protection functionality

Required Methods§

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fn eagerly_mmap_all_spaces(&self, space_map: &[Address])

Given an address array describing the regions of virtual memory to be used by MMTk, demand zero map all of them if they are not already mapped.

Arguments:

spaceMap: An address array containing a pairs of start and end addresses for each of the regions to be mapped

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fn mark_as_mapped(&self, start: Address, bytes: usize)

Mark a number of pages as mapped, without making any request to the operating system. Used to mark pages that the VM has already mapped.

Arguments:

start: Address of the first page to be mapped
bytes: Number of bytes to ensure mapped

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fn quarantine_address_range( &self, start: Address, pages: usize, strategy: MmapStrategy ) -> Result<()>

Quarantine/reserve address range. We mmap from the OS with no reserve and with PROT_NONE, which should be little overhead. This ensures that we can reserve certain address range that we can use if needed. Quarantined memory needs to be mapped before it can be used.

Arguments:

start: Address of the first page to be quarantined
bytes: Number of bytes to quarantine from the start

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fn ensure_mapped( &self, start: Address, pages: usize, strategy: MmapStrategy ) -> Result<()>

Ensure that a range of pages is mmapped (or equivalent). If the pages are not yet mapped, demand-zero map them. Note that mapping occurs at chunk granularity, not page granularity.

Arguments: