Function dealloc 

pub unsafe fn dealloc(location: NonNull<u8>, size: usize) -> Result<()>

Deallocate previously allocated virtual pages, releasing them to the OS.

This operation is also called “unmapping” or “releasing”.

Errors

Returns Error::InvalidInput if:

• location is not aligned to the page size, or
• size is not a multiple of page size.

Safety

For portability, location and size must exactly match the memory range reserved via alloc.

Platform specific:

• On Windows, only location must exactly match the start of the memory range reserved via alloc, and size is ignored.
• On Unix, you can unreserve a subrange, i.e. location and size must be currently reserved, but do not need to match exactly match the memory range reserved via alloc.

Undefined behavior if location + size overflows.

Examples

let ptr = unsafe {
    pagealloc::alloc(
        std::ptr::null_mut(),
        pagealloc::alloc_granularity(),
        pagealloc::Protection::ReadWrite,
    )?
};
// ...
unsafe { pagealloc::dealloc(ptr, pagealloc::alloc_granularity())? };