pub unsafe fn discard(ptr: NonNull<u8>, len: usize) -> boolExpand description
Return the physical pages backing len bytes at ptr to the OS
while keeping the range mapped and addressable.
The range must be page-aligned and a whole number of pages. Contents are discarded: a later read sees zeroes, which is why only spans with no live slots are ever passed here.
ยงSafety
ptr/len must lie inside a live mapping from map_aligned, and
no live data may remain in the range.