On Wed, Apr 27, 2022 at 08:14:09PM +0800, Kefeng Wang wrote: > Let's arm64 use GENERIC_IOREMAP to cleanup code, and > support ioremap_prot()/HAVE_IOREMAP_PROT, which could > enable generic_access_phys(). > > Kefeng Wang (4): > mm: ioremap: Setup phys_addr of struct vm_struct > mm: ioremap: Add arch_ioremap/iounmap_check() > arm64: mm: Convert to GENERIC_IOREMAP > arm64: Add HAVE_IOREMAP_PROT support > > .../features/vm/ioremap_prot/arch-support.txt | 2 +- > arch/arm64/Kconfig | 2 + > arch/arm64/include/asm/io.h | 14 +-- > arch/arm64/include/asm/pgtable.h | 10 +++ > arch/arm64/kernel/acpi.c | 2 +- > arch/arm64/mm/hugetlbpage.c | 10 --- > arch/arm64/mm/ioremap.c | 86 +++---------------- > include/asm-generic/io.h | 3 + > mm/ioremap.c | 21 ++++- > 9 files changed, 56 insertions(+), 94 deletions(-) That's not a massively compelling diffstat for a cleanup, in all honesty. I looked at generic_access_phys() to try to figure out why we would want that on arm64, but it seems like it's related to mmap() of devices in userspace. Bearing in mind that CONFIG_STRICT_DEVMEM=y by default, please can you justify why this is something worth doing? Will
