Re: [PATCH V5 3/4] arm64: apei: implement arch_apei_get_mem_attributes()

[Will Deacon <will.deacon@arm.com>]

On Wed, Jul 15, 2015 at 01:31:55AM +0100, Jonathan (Zhixiong) Zhang wrote:
> From: "Jonathan (Zhixiong) Zhang" <zjzhang@codeaurora.org>
> 
> If the physical address has memory attributes defined by EFI
> memmap as EFI_MEMORY_UC, the page protection type is
> PROT_DEVICE_nGnRE. Otherwise, the page protection type is
> PAGE_KERNEL.
> 
> Signed-off-by: Jonathan (Zhixiong) Zhang <zjzhang@codeaurora.org>
> ---
>  arch/arm64/kernel/Makefile |  1 +
>  arch/arm64/kernel/apei.c   | 27 +++++++++++++++++++++++++++
>  2 files changed, 28 insertions(+)
>  create mode 100644 arch/arm64/kernel/apei.c
> 
> diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
> index 426d0763c81b..c135f1e4e3b8 100644
> --- a/arch/arm64/kernel/Makefile
> +++ b/arch/arm64/kernel/Makefile
> @@ -36,6 +36,7 @@ arm64-obj-$(CONFIG_EFI)			+= efi.o efi-stub.o efi-entry.o
>  arm64-obj-$(CONFIG_PCI)			+= pci.o
>  arm64-obj-$(CONFIG_ARMV8_DEPRECATED)	+= armv8_deprecated.o
>  arm64-obj-$(CONFIG_ACPI)		+= acpi.o
> +arm64-obj-$(CONFIG_ACPI_APEI)		+= apei.o
>  
>  obj-y					+= $(arm64-obj-y) vdso/
>  obj-m					+= $(arm64-obj-m)
> diff --git a/arch/arm64/kernel/apei.c b/arch/arm64/kernel/apei.c
> new file mode 100644
> index 000000000000..9c6b62f40ad7
> --- /dev/null
> +++ b/arch/arm64/kernel/apei.c
> @@ -0,0 +1,27 @@
> +/*
> + * Arch-specific APEI-related functions.
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License as published by
> + * the Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <acpi/apei.h>
> +
> +#include <linux/efi.h>
> +
> +#include <asm/pgtable.h>
> +
> +pgprot_t arch_apei_get_mem_attribute(phys_addr_t addr)
> +{
> +	if (efi_mem_attributes(addr) & EFI_MEMORY_UC)
> +		return PROT_DEVICE_nGnRE;
> +	else
> +		return PAGE_KERNEL;
> +}

Do we really need a new file and out-of-line call for this?

Will