[RFC V2 0/2] arm64: Enable vmemmap mapping from device memory

[Anshuman Khandual <anshuman.khandual@arm.com>]

This series enables vmemmap backing memory allocation from device memory
ranges on arm64. But before that, it enables vmemmap_populate_basepages()
to accommodate struct vmem_altmap based requests.

This applies alongside arm64 memory hot remove (v10) on next-20191018.

https://lkml.org/lkml/2019/10/11/232

Changes in RFC V2:

- Changed the commit message on 1/2 patch per Will
- Changed the commit message on 2/2 patch as well
- Rebased on arm64 memory hot remove series (v10)

RFC V1: (https://lkml.org/lkml/2019/6/28/32)

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-ia64@vger.kernel.org
Cc: linux-riscv@lists.infradead.org
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org

Anshuman Khandual (2):
  mm/sparsemem: Enable vmem_altmap support in vmemmap_populate_basepages()
  arm64/mm: Enable vmem_altmap support for vmemmap mappings

 arch/arm64/mm/mmu.c      | 58 +++++++++++++++++++++++++++-------------
 arch/ia64/mm/discontig.c |  2 +-
 arch/riscv/mm/init.c     |  2 +-
 arch/x86/mm/init_64.c    |  6 ++---
 include/linux/mm.h       |  5 ++--
 mm/sparse-vmemmap.c      | 16 +++++++----
 6 files changed, 59 insertions(+), 30 deletions(-)

-- 
2.20.1