From: "Jonathan (Zhixiong) Zhang" <[email protected]> ... to allow arch specific implementation of getting page protection type associated with a physical address.
On x86, we currently have no way to lookup the EFI memory map attributes for a region in a consistent way because the memmap is discarded after efi_free_boot_services(). So if you call efi_mem_attributes() during boot and at runtime, you could theoretically see different attributes. Since we are yet to see any x86 platforms that require anything other than PAGE_KERNEL (some arm64 platforms require the equivalent of PAGE_KERNEL_NOCACHE), return that until we know differently. Signed-off-by: Jonathan (Zhixiong) Zhang <[email protected]> --- arch/x86/include/asm/acpi.h | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/arch/x86/include/asm/acpi.h b/arch/x86/include/asm/acpi.h index 3a45668f6dc3..ffe22c6b17bd 100644 --- a/arch/x86/include/asm/acpi.h +++ b/arch/x86/include/asm/acpi.h @@ -32,6 +32,10 @@ #include <asm/mpspec.h> #include <asm/realmode.h> +#ifdef CONFIG_ACPI_APEI +#include <asm/pgtable_types.h> +#endif + #ifdef CONFIG_ACPI extern int acpi_lapic; extern int acpi_ioapic; @@ -147,4 +151,24 @@ extern int x86_acpi_numa_init(void); #define acpi_unlazy_tlb(x) leave_mm(x) +#ifdef CONFIG_ACPI_APEI +static inline pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr) +{ + /* + * We currently have no way to lookup the EFI memory map + * attributes for a region in a consistent way because the + * memmap is discarded after efi_free_boot_services(). So if + * you call efi_mem_attributes() during boot and at runtime, + * you could theoretically see different attributes. + * + * Since we are yet to see any x86 platforms that require + * anything other than PAGE_KERNEL (some arm64 platforms + * require the equivalent of PAGE_KERNEL_NOCACHE), return that + * until we know differently. + */ + + return PAGE_KERNEL; +} +#endif + #endif /* _ASM_X86_ACPI_H */ -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
