On Mon, May 10, 2021 at 11:03 PM Christoph Hellwig <hch@xxxxxx> wrote: > > > +static inline struct io_tlb_mem *get_io_tlb_mem(struct device *dev) > > +{ > > +#ifdef CONFIG_DMA_RESTRICTED_POOL > > + if (dev && dev->dma_io_tlb_mem) > > + return dev->dma_io_tlb_mem; > > +#endif /* CONFIG_DMA_RESTRICTED_POOL */ > > + > > + return io_tlb_default_mem; > > Given that we're also looking into a not addressing restricted pool > I'd rather always assign the active pool to dev->dma_io_tlb_mem and > do away with this helper. Where do you think is the proper place to do the assignment? First time calling swiotlb_map? or in of_dma_configure_id?