On Wed, 2026-08-05 at 10:50 +0200, Andreas Hindborg wrote: > "Philipp Stanner" <[email protected]> writes: > > > One often cannot allocate in the kernel with the desired flags, most > > notably in atomic context. Pre-allocating the memory is the preferred > > solution in such situations. > > > > Add support for xa_reserve() in the Rust abstractions of xarray. Create > > a Reservation object similar to a lock-guard, that can be dropped once > > the reservation is no longer needed or once the index was stored to. > > > > Signed-off-by: Philipp Stanner <[email protected]> > > --- > > Please regard this more as an RFC. > > > > I need pre-allocating in XArray for DmaFence. How exactly we achieve > > this is open for discussion. > > Do you need to actually reserve a key, or do you just need atomic > allocation?
I would just have needed a position to store to, but the fence sequence number would be the only reasonable index, so you'd also reserve a key. Anyways, please forget about this for now, we abstained from using the XArray in the current revision (v8) of this patch series. Thx P.
