Messages in this thread | | | Date | Wed, 08 Apr 2009 15:36:58 -0700 | From | Jeremy Fitzhardinge <> | Subject | Re: [PATCH 4/7] swiotlb: Allow arch override of address_needs_mapping |
| |
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.
>> 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
| |