Re: [PATCH 12/12] mm: Remove devmap related functions and page table bits

Chunyan Zhang
2024-09-11T07:48:01Z

Hi Alistair,

On Tue, 10 Sept 2024 at 12:21, Alistair Popple <apopple@nvidia.com> wrote:
>
> Now that DAX and all other reference counts to ZONE_DEVICE pages are
> managed normally there is no need for the special devmap PTE/PMD/PUD
> page table bits. So drop all references to these, freeing up a
> software defined page table bit on architectures supporting it.
>
> Signed-off-by: Alistair Popple <apopple@nvidia.com>
> Acked-by: Will Deacon <will@kernel.org> # arm64
> ---
> Documentation/mm/arch_pgtable_helpers.rst | 6 +--
> arch/arm64/Kconfig | 1 +-
> arch/arm64/include/asm/pgtable-prot.h | 1 +-
> arch/arm64/include/asm/pgtable.h | 24 +--------
> arch/powerpc/Kconfig | 1 +-
> arch/powerpc/include/asm/book3s/64/hash-4k.h | 6 +--
> arch/powerpc/include/asm/book3s/64/hash-64k.h | 7 +--
> arch/powerpc/include/asm/book3s/64/pgtable.h | 52 +------------------
> arch/powerpc/include/asm/book3s/64/radix.h | 14 +-----
> arch/x86/Kconfig | 1 +-
> arch/x86/include/asm/pgtable.h | 50 +-----------------
> arch/x86/include/asm/pgtable_types.h | 5 +--

RISC-V's references also need to be cleanup, it simply can be done by
reverting the commit

216e04bf1e4d (riscv: mm: Add support for ZONE_DEVICE)

Thanks,
Chunyan

> include/linux/mm.h | 7 +--
> include/linux/pfn_t.h | 20 +-------
> include/linux/pgtable.h | 19 +------
> mm/Kconfig | 4 +-
> mm/debug_vm_pgtable.c | 59 +--------------------
> mm/hmm.c | 3 +-
> 18 files changed, 11 insertions(+), 269 deletions(-)
>