[tip:efi/core] efi/arm*: Use memremap() to create the persistent memmap mapping

[tip-bot for Ard Biesheuvel]

Commit-ID:  24d45d1dc275b818093fe1d0055a230ce5e8c4c7
Gitweb:     http://git.kernel.org/tip/24d45d1dc275b818093fe1d0055a230ce5e8c4c7
Author:     Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
AuthorDate: Mon, 25 Apr 2016 21:06:41 +0100
Committer:  Ingo Molnar <mingo@xxxxxxxxxx>
CommitDate: Thu, 28 Apr 2016 11:33:52 +0200

efi/arm*: Use memremap() to create the persistent memmap mapping

Instead of using ioremap_cache(), which is slightly inappropriate for
mapping firmware tables, and is not even allowed on ARM for mapping
regions that are covered by a struct page, use memremap(), which was
invented for this purpose, and will also reuse the existing kernel
direct mapping if the requested region is covered by it.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Signed-off-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: linux-efi@xxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1461614832-17633-10-git-send-email-matt@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
 drivers/firmware/efi/arm-runtime.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/firmware/efi/arm-runtime.c b/drivers/firmware/efi/arm-runtime.c
index 55a9ea0..19283de 100644
--- a/drivers/firmware/efi/arm-runtime.c
+++ b/drivers/firmware/efi/arm-runtime.c
@@ -105,8 +105,7 @@ static int __init arm_enable_runtime_services(void)
 
 	mapsize = efi.memmap.map_end - efi.memmap.map;
 
-	efi.memmap.map = (__force void *)ioremap_cache(efi.memmap.phys_map,
-						       mapsize);
+	efi.memmap.map = memremap(efi.memmap.phys_map, mapsize, MEMREMAP_WB);
 	if (!efi.memmap.map) {
 		pr_err("Failed to remap EFI memory map\n");
 		return -ENOMEM;