On Thu, Jan 21, 2016 at 06:39:36PM +1100, Alexey Kardashevskiy wrote: > Upcoming multi-tce support (H_PUT_TCE_INDIRECT/H_STUFF_TCE hypercalls) > will validate TCE (not to have unexpected bits) and IO address > (to be within the DMA window boundaries). > > This introduces helpers to validate TCE and IO address. The helpers are > exported as they compile into vmlinux (to work in realmode) and will be > used later by KVM kernel module in virtual mode.
Comments below... > +/* Note on the use of page_address() in real mode, > + * > + * It is safe to use page_address() in real mode on ppc64 because > + * page_address() is always defined as lowmem_page_address() > + * which returns __va(PFN_PHYS(page_to_pfn(page))) which is arithmetial "arithmetic" not "arithmetial" > + * operation and does not access page struct. > + * > + * Theoretically page_address() could be defined different > + * but either WANT_PAGE_VIRTUAL or HASHED_PAGE_VIRTUAL > + * should be enabled. "would have to be enabled" not "should be enabled" Apart from those nits, the patch looks fine. Paul. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
