Messages in this thread | | | Date | Wed, 29 Jun 2016 10:37:31 -0500 | From | Reza Arbab <> | Subject | Re: [PATCH] powerpc/mm: update arch_{add,remove}_memory() for radix |
| |
On Tue, Jun 28, 2016 at 09:21:05PM +1000, Michael Ellerman wrote: >No, you need to use mmu_linear_psize for the hotplug case. > >But you can probably factor out a common routine that both cases use, and hide >the hash vs radix check in that.
Okay, I'm trying to refactor {create,remove}_section_mapping() into hash__ and radix__ variants. This lead to a couple of questions.
Pseudocode for radix__create_section_mapping(start, end):
page_size = 1 << mmu_psize_defs[mmu_linear_psize].shift; start = _ALIGN_DOWN(start, page_size);
for (; start < end; start += page_size) { radix__map_kernel_page(start, __pa(start), PAGE_KERNEL, page_size); }
Should the above use PAGE_KERNEL, like the the hash table bolt, or (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_KERNEL_RW), like in the radix vmemmap creation?
The other question is what radix__remove_section_mapping() should do. I don't know offhand what the opposite of map_kernel_page() is. As Aneesh mentioned, radix vmemmap removal is currently stubbed as a FIXME so I couldn't use that as a reference.
-- Reza Arbab
| |