Struct MemoryMappingArena

pub struct MemoryMappingArena {
    addr: *mut u8,
    size: usize,
}

Tracks Fixed Memory Maps within an anonymous memory-mapped fixed-sized arena in the current process.

Fields

addr: *mut u8

size: usize

Implementations

impl MemoryMappingArena

pub fn new(size: usize) -> Result<MemoryMappingArena>

Creates an mmap arena of size bytes.

Arguments

• size - Size of memory region in bytes.

pub fn add_anon_protection( &mut self, offset: usize, size: usize, prot: Protection, ) -> Result<()>

Anonymously maps size bytes at offset bytes from the start of the arena with prot protections. offset must be page aligned.

Arguments

• offset - Page aligned offset into the arena in bytes.
• size - Size of memory region in bytes.
• prot - Protection (e.g. readable/writable) of the memory region.

pub fn add_anon(&mut self, offset: usize, size: usize) -> Result<()>

Anonymously maps size bytes at offset bytes from the start of the arena. offset must be page aligned.

Arguments

• offset - Page aligned offset into the arena in bytes.
• size - Size of memory region in bytes.

pub fn add_fd( &mut self, offset: usize, size: usize, fd: &dyn AsRawDescriptor, ) -> Result<()>

Maps size bytes from the start of the given fd at offset bytes from the start of the arena. offset must be page aligned.

Arguments

• offset - Page aligned offset into the arena in bytes.
• size - Size of memory region in bytes.
• fd - File descriptor to mmap from.

pub fn add_fd_offset( &mut self, offset: usize, size: usize, fd: &dyn AsRawDescriptor, fd_offset: u64, ) -> Result<()>

Maps size bytes starting at fs_offset bytes from within the given fd at offset bytes from the start of the arena. offset must be page aligned.

Arguments

• offset - Page aligned offset into the arena in bytes.
• size - Size of memory region in bytes.
• fd - File descriptor to mmap from.
• fd_offset - Offset in bytes from the beginning of fd to start the mmap.

pub fn add_fd_offset_protection( &mut self, offset: usize, size: usize, fd: &dyn AsRawDescriptor, fd_offset: u64, prot: Protection, ) -> Result<()>

Maps size bytes starting at fs_offset bytes from within the given fd at offset bytes from the start of the arena with prot protections. offset must be page aligned.

Arguments

• offset - Page aligned offset into the arena in bytes.
• size - Size of memory region in bytes.
• fd - File descriptor to mmap from.
• fd_offset - Offset in bytes from the beginning of fd to start the mmap.
• prot - Protection (e.g. readable/writable) of the memory region.

fn try_add( &mut self, offset: usize, size: usize, prot: Protection, fd: Option<(&dyn AsRawDescriptor, u64)>, ) -> Result<()>

Helper method that calls appropriate MemoryMapping constructor and adds the resulting map into the arena.

pub fn remove(&mut self, offset: usize, size: usize) -> Result<()>

Removes size bytes at offset bytes from the start of the arena. offset must be page aligned.

Arguments

• offset - Page aligned offset into the arena in bytes.
• size - Size of memory region in bytes.

Trait Implementations

impl Drop for MemoryMappingArena

fn drop(&mut self)

Executes the destructor for this type.

impl From<MemoryMapping> for MemoryMappingArena

fn from(mmap: MemoryMapping) -> Self

Converts to this type from the input type.

impl From<MemoryMapping> for MemoryMappingArena

fn from(mmap: CrateMemoryMapping) -> Self

Converts to this type from the input type.

impl MappedRegion for MemoryMappingArena

fn as_ptr(&self) -> *mut u8

Returns a pointer to the beginning of the memory region. Should only be used for passing this region to ioctls for setting guest memory.

fn size(&self) -> usize

Returns the size of the memory region in bytes.

fn add_fd_mapping( &mut self, offset: usize, size: usize, fd: &dyn AsRawDescriptor, fd_offset: u64, prot: Protection, ) -> Result<()>

Maps size bytes starting at fd_offset bytes from within the given fd at offset bytes from the start of the region with prot protections. offset must be page aligned.

fn remove_mapping(&mut self, offset: usize, size: usize) -> Result<()>

Remove size-byte mapping starting at offset.

impl Send for MemoryMappingArena

impl Sync for MemoryMappingArena