This series enables vmemmap backing memory allocation from device memory ranges on arm64. But before that, it enables vmemmap_populate_basepages() and vmemmap_alloc_block_buf() to accommodate struct vmem_altmap based alocation requests. This series applies after latest (v14) arm64 memory hot remove series (https://lkml.org/lkml/2020/3/3/1746) on Linux 5.6. Pending Question: altmap_alloc_block_buf() does not have any other remaining users in the tree after this change. Should it be converted into a static function and it's declaration be dropped from the header (include/linux/mm.h). Avoided doing so because I was not sure if there are any off-tree users or not. Changes in V3: - Dropped comment from free_hotplug_page_range() per Robin - Modified comment in unmap_hotplug_range() per Robin - Enabled altmap support in vmemmap_alloc_block_buf() per Robin Changes in V2: (https://lkml.org/lkml/2020/3/4/475) - Rebased on latest hot-remove series (v14) adding P4D page table support Changes in V1: (https://lkml.org/lkml/2020/1/23/12) - Added an WARN_ON() in unmap_hotplug_range() when altmap is provided without the page table backing memory being freed Changes in RFC V2: (https://lkml.org/lkml/2019/10/21/11) - 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@xxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx> Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linux-ia64@xxxxxxxxxxxxxxx Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx Cc: x86@xxxxxxxxxx Cc: linuxppc-dev@xxxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Anshuman Khandual (3): mm/sparsemem: Enable vmem_altmap support in vmemmap_populate_basepages() mm/sparsemem: Enable vmem_altmap support in vmemmap_alloc_block_buf() arm64/mm: Enable vmem_altmap support for vmemmap mappings arch/arm64/mm/mmu.c | 59 ++++++++++++++++++++++++++------------- arch/ia64/mm/discontig.c | 2 +- arch/powerpc/mm/init_64.c | 10 +++---- arch/riscv/mm/init.c | 2 +- arch/x86/mm/init_64.c | 12 ++++---- include/linux/mm.h | 8 ++++-- mm/sparse-vmemmap.c | 38 ++++++++++++++++++++----- 7 files changed, 87 insertions(+), 44 deletions(-) -- 2.20.1
