linux/arch/x86/platform/efi
Matt Fleming 9479c7cebf efi: Refactor efi_memmap_init_early() into arch-neutral code
Every EFI architecture apart from ia64 needs to setup the EFI memory
map at efi.memmap, and the code for doing that is essentially the same
across all implementations. Therefore, it makes sense to factor this
out into the common code under drivers/firmware/efi/.

The only slight variation is the data structure out of which we pull
the initial memory map information, such as physical address, memory
descriptor size and version, etc. We can address this by passing a
generic data structure (struct efi_memory_map_data) as the argument to
efi_memmap_init_early() which contains the minimum info required for
initialising the memory map.

In the process, this patch also fixes a few undesirable implementation
differences:

 - ARM and arm64 were failing to clear the EFI_MEMMAP bit when
   unmapping the early EFI memory map. EFI_MEMMAP indicates whether
   the EFI memory map is mapped (not the regions contained within) and
   can be traversed.  It's more correct to set the bit as soon as we
   memremap() the passed in EFI memmap.

 - Rename efi_unmmap_memmap() to efi_memmap_unmap() to adhere to the
   regular naming scheme.

This patch also uses a read-write mapping for the memory map instead
of the read-only mapping currently used on ARM and arm64. x86 needs
the ability to update the memory map in-place when assigning virtual
addresses to regions (efi_map_region()) and tagging regions when
reserving boot services (efi_reserve_boot_services()).

There's no way for the generic fake_mem code to know which mapping to
use without introducing some arch-specific constant/hook, so just use
read-write since read-only is of dubious value for the EFI memory map.

Tested-by: Dave Young <dyoung@redhat.com> [kexec/kdump]
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> [arm]
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Cc: Peter Jones <pjones@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
2016-09-09 16:06:38 +01:00
..
early_printk.c treewide: replace obsolete _refok by __ref 2016-08-02 17:31:41 -04:00
efi_32.c x86/mm: Remove kernel_unmap_pages_in_pgd() and efi_cleanup_page_tables() 2016-07-15 10:26:26 +02:00
efi_64.c x86/efi: Consolidate region mapping logic 2016-09-09 16:06:37 +01:00
efi_stub_32.S x86/efi: Mark initialization code as such 2014-10-03 18:41:03 +01:00
efi_stub_64.S x86/efi: Fix 7-parameter efi_call()s 2016-05-17 08:25:06 +02:00
efi_thunk_64.S x86/efi: Avoid triple faults during EFI mixed mode calls 2015-02-13 15:42:56 +00:00
efi-bgrt.c x86/efi-bgrt: Switch all pr_err() to pr_notice() for invalid BGRT 2016-05-04 08:36:44 +02:00
efi.c efi: Refactor efi_memmap_init_early() into arch-neutral code 2016-09-09 16:06:38 +01:00
Makefile objtool: Mark non-standard object files and directories 2016-02-29 08:35:02 +01:00
quirks.c efi: Refactor efi_memmap_init_early() into arch-neutral code 2016-09-09 16:06:38 +01:00