[PATCH 3/3] rust: maple_tree: add MapleTreeAlloc

[Alice Ryhl]

On Thu, Aug 07, 2025 at 12:29:19PM -0400, Liam R. Howlett wrote:
> * Alice Ryhl <aliceryhl at google.com> [250726 09:23]:
> > To support allocation trees, we introduce a new type MapleTreeAlloc for
> > the case where the tree is created using MT_FLAGS_ALLOC_RANGE. To ensure
> > that you can only call mtree_alloc_range on an allocation tree, we
> > restrict thta method to the new MapleTreeAlloc type. However, all
> Typo here  ^
> 
> > methods on MapleTree remain accessible to MapleTreeAlloc as allocation
> > trees can use the other methods without issues.
> 
> I guess this is for some rust side error translation because the C side
> already returns the error?

Already returns what error?

The API here makes it so that it fails to compile when you call
alloc_range on a tree that isn't an allocation tree. That's why there is
a separate type.

Alice