From: Anshuman Khandual <anshuman.khandual@arm.com> mainline inclusion from mainline-v5.3-rc1 commit 0f472d04f59ff89d15b2a1c4eafde7317ddd67a2 category: feature bugzilla: NA CVE: NA Drop the support for powerpc platform. --------------------------- Finish up what commit c2febafc6773 ("mm: convert generic code to 5-level paging") started while levelling up P4D huge mapping support at par with PUD and PMD. A new arch call back arch_ioremap_p4d_supported() is added which just maintains status quo (P4D huge map not supported) on x86, arm64 and powerpc. When HAVE_ARCH_HUGE_VMAP is enabled its just a simple check from the arch about the support, hence runtime effects are minimal. Link: http://lkml.kernel.org/r/1561699231-20991-1-git-send-email-anshuman.khandual... Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Rui Xiang <rui.xiang@huawei.com> Reviewed-by: Ding Tianhong <dingtianhong@huawei.com> Reviewed-by: Zefan Li <lizefan@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> --- arch/arm64/mm/mmu.c | 5 +++++ arch/x86/mm/ioremap.c | 5 +++++ include/linux/io.h | 1 + lib/ioremap.c | 2 ++ 4 files changed, 13 insertions(+) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 99a86326a301..437ee4ab41a1 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -921,6 +921,11 @@ void *__init fixmap_remap_fdt(phys_addr_t dt_phys) return dt_virt; } +int __init arch_ioremap_p4d_supported(void) +{ + return 0; +} + int __init arch_ioremap_pud_supported(void) { /* diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c index adc77904fc3e..6ce8a2b593e0 100644 --- a/arch/x86/mm/ioremap.c +++ b/arch/x86/mm/ioremap.c @@ -431,6 +431,11 @@ void iounmap(volatile void __iomem *addr) } EXPORT_SYMBOL(iounmap); +int __init arch_ioremap_p4d_supported(void) +{ + return 0; +} + int __init arch_ioremap_pud_supported(void) { #ifdef CONFIG_X86_64 diff --git a/include/linux/io.h b/include/linux/io.h index da39ff89df65..6cbd11b951ec 100644 --- a/include/linux/io.h +++ b/include/linux/io.h @@ -45,6 +45,7 @@ static inline int ioremap_page_range(unsigned long addr, unsigned long end, #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP void __init ioremap_huge_init(void); +int arch_ioremap_p4d_supported(void); int arch_ioremap_pud_supported(void); int arch_ioremap_pmd_supported(void); #else diff --git a/lib/ioremap.c b/lib/ioremap.c index 063213685563..c3dc213b6980 100644 --- a/lib/ioremap.c +++ b/lib/ioremap.c @@ -30,6 +30,8 @@ early_param("nohugeiomap", set_nohugeiomap); void __init ioremap_huge_init(void) { if (!ioremap_huge_disabled) { + if (arch_ioremap_p4d_supported()) + ioremap_p4d_capable = 1; if (arch_ioremap_pud_supported()) ioremap_pud_capable = 1; if (arch_ioremap_pmd_supported()) -- 2.25.1