When reading the page_pool code the first impression is that keeping
two separate counters, one being the page refcnt and the other being
fragment pp_frag_count, is counter-intuitive.
However without that fragment counter we don't know when to reliably
destroy or sync the outstanding DMA mappings. So let's add a comment
explaining this part.
Reviewed-by: Alexander Duyck <[email protected]>
Signed-off-by: Ilias Apalodimas <[email protected]>
Acked-by: Jesper Dangaard Brouer <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>