Messages in this thread |  | | | Date | Thu, 9 Apr 2009 08:01:18 +0900 | | Subject | Re: [PATCH 4/7] swiotlb: Allow arch override of address_needs_mapping | | From | FUJITA Tomonori <> |
| |
On Wed, 08 Apr 2009 15:36:58 -0700 Jeremy Fitzhardinge <jeremy@goop.org> wrote:
> FUJITA Tomonori wrote: > >> Some architectures need non-trivial bus<->phys conversion routines, etc, > >> > > > > Only Xen needs such conversion for swiotlb. > > > > Becky's patches of last week also added __weak annotations to > swiotlb_bus_to_virt, virt_to_bus and bus_to_phys; added the hwdev > parameter to swiotlb_bus_to_phys; and added a weak > swiotlb_arch_address_needs_mapping. I assume that was needed because > powerpc needs non-trivial implementations for those functions.
Hmm, what she added are wrappers of virt_to_bus and bus_to_virt. We can remove these and directly use virt_to_bus and bus_to_virt.
About __weak address_needs_mapping function, as I said, removing it and using dma_map_ops is a proper solution.
> >> so either we can require it that all architectures wishing to use > >> swiotlb define these functions, or have weak default functions that can > >> be overridden by architectures where necessary. > >> > > > > Can you give an example? I don't think IA64, X86_64 or POWER (which > > will use swiotlb) need any __weak functions. If you say other archs > > could use swiotlb, please tell me how they need these __weak. > > > > As I said, Becky's patches added hooks in many of the places we added > them for Xen. I assume that's because powerpc needs them; I have not > seen the arch/powerpc side of those changes. > > J > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/
|  |