On Thu, Jun 18, 2020 at 06:45:28AM +0530, Anshuman Khandual wrote: > vmemmap_populate_basepages() is used across platforms to allocate backing > memory for vmemmap mapping. This is used as a standard default choice or > as a fallback when intended huge pages allocation fails. This just creates > entire vmemmap mapping with base pages (PAGE_SIZE). > > On arm64 platforms, vmemmap_populate_basepages() is called instead of the > platform specific vmemmap_populate() when ARM64_SWAPPER_USES_SECTION_MAPS > is not enabled as in case for ARM64_16K_PAGES and ARM64_64K_PAGES configs. > > At present vmemmap_populate_basepages() does not support allocating from > driver defined struct vmem_altmap while trying to create vmemmap mapping > for a device memory range. It prevents ARM64_16K_PAGES and ARM64_64K_PAGES > configs on arm64 from supporting device memory with vmemap_altmap request. > > This enables vmem_altmap support in vmemmap_populate_basepages() unlocking > device memory allocation for vmemap mapping on arm64 platforms with 16K or > 64K base page configs. > > Each architecture should evaluate and decide on subscribing device memory > based base page allocation through vmemmap_populate_basepages(). Hence lets > keep it disabled on all archs in order to preserve the existing semantics. > A subsequent patch enables it on arm64. > > Cc: Catalin Marinas <catalin.mari...@arm.com> > Cc: Will Deacon <w...@kernel.org> > Cc: Mark Rutland <mark.rutl...@arm.com> > Cc: Paul Walmsley <paul.walms...@sifive.com> > Cc: Palmer Dabbelt <pal...@dabbelt.com> > Cc: Tony Luck <tony.l...@intel.com> > Cc: Fenghua Yu <fenghua...@intel.com> > Cc: Dave Hansen <dave.han...@linux.intel.com> > Cc: Andy Lutomirski <l...@kernel.org> > Cc: Peter Zijlstra <pet...@infradead.org> > Cc: Thomas Gleixner <t...@linutronix.de> > Cc: Ingo Molnar <mi...@redhat.com> > Cc: David Hildenbrand <da...@redhat.com> > Cc: Mike Rapoport <r...@linux.ibm.com> > Cc: Michal Hocko <mho...@suse.com> > Cc: "Matthew Wilcox (Oracle)" <wi...@infradead.org> > Cc: "Kirill A. Shutemov" <kirill.shute...@linux.intel.com> > Cc: Andrew Morton <a...@linux-foundation.org> > Cc: Dan Williams <dan.j.willi...@intel.com> > Cc: Pavel Tatashin <pasha.tatas...@soleen.com> > Cc: linux-arm-ker...@lists.infradead.org > Cc: linux-i...@vger.kernel.org > Cc: linux-ri...@lists.infradead.org > Cc: x...@kernel.org > Cc: linux-kernel@vger.kernel.org > Tested-by: Jia He <justin...@arm.com> > Acked-by: Will Deacon <w...@kernel.org> > Signed-off-by: Anshuman Khandual <anshuman.khand...@arm.com>
For arm64: Acked-by: Catalin Marinas <catalin.mari...@arm.com>
