On Fri, Jan 22, 2021 at 03:58:01PM +0200, Lauri Kasanen wrote: > On Fri, 22 Jan 2021 11:17:27 +0000 > Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: > > > Sorry for not noticing this earlier, but why do you need the bounce > > buffer vs just mapping the data buffer? > > I think I've answered this once already a few iterations before. DMA > alignment restrictions, not sure what guarantees the bio buffer has. Your driver can communicate the required alignment using the blk_queue_update_dma_alignment API.