On Mon, Feb 11, 2019 at 08:53:19AM +0000, Tariq Toukan wrote: > It's great to use the struct page to store its dma mapping, but I am > worried about extensibility. > page_pool is evolving, and it would need several more per-page fields. > One of them would be pageref_bias, a planned optimization to reduce the > number of the costly atomic pageref operations (and replace existing > code in several drivers).
There's space for five words (20 or 40 bytes on 32/64 bit).
