Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965125AbcDYUL1 (ORCPT ); Mon, 25 Apr 2016 16:11:27 -0400 Received: from mail-wm0-f52.google.com ([74.125.82.52]:37281 "EHLO mail-wm0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933528AbcDYUIS (ORCPT ); Mon, 25 Apr 2016 16:08:18 -0400 From: Matt Fleming To: Ingo Molnar , Thomas Gleixner , "H . Peter Anvin" Cc: Mark Rutland , Ard Biesheuvel , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, Matt Fleming , Catalin Marinas , Leif Lindholm , Russell King , Will Deacon Subject: [PATCH 31/40] efi/runtime-wrappers: Add {__,}efi_call_virt templates Date: Mon, 25 Apr 2016 21:07:03 +0100 Message-Id: <1461614832-17633-32-git-send-email-matt@codeblueprint.co.uk> X-Mailer: git-send-email 2.7.3 In-Reply-To: <1461614832-17633-1-git-send-email-matt@codeblueprint.co.uk> References: <1461614832-17633-1-git-send-email-matt@codeblueprint.co.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3415 Lines: 101 From: Mark Rutland Currently each architecture must implement two macros, efi_call_virt and __efi_call_virt, which only differ by the presence or absence of a return type. Otherwise, the logic surrounding the call is identical. As each architecture must define the entire body of each, we can't place any generic manipulation (e.g. irq flag validation) in the middle. This patch adds template implementations of these macros. With these, arch code can implement three template macros, avoiding reptition for the void/non-void return cases: * arch_efi_call_virt_setup Sets up the environment for the call (e.g. switching page tables, allowing kernel-mode use of floating point, if required). * arch_efi_call_virt Performs the call. The last expression in the macro must be the call itself, allowing the logic to be shared by the void and non-void cases. * arch_efi_call_virt_teardown Restores the usual kernel environment once the call has returned. While the savings from repition are minimal, we additionally gain the ability to add common code around the call with the call environment set up. This can be used to detect common firmware issues (e.g. bad irq mask management). Signed-off-by: Mark Rutland Reviewed-by: Ard Biesheuvel Cc: linux-efi@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Catalin Marinas Cc: "H. Peter Anvin" Cc: Leif Lindholm Cc: Russell King Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Matt Fleming --- drivers/firmware/efi/runtime-wrappers.c | 40 +++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/drivers/firmware/efi/runtime-wrappers.c b/drivers/firmware/efi/runtime-wrappers.c index de6953039af6..0677577bdaa1 100644 --- a/drivers/firmware/efi/runtime-wrappers.c +++ b/drivers/firmware/efi/runtime-wrappers.c @@ -21,6 +21,46 @@ #include /* + * Arch code can implement the following three template macros, avoiding + * reptition for the void/non-void return cases of {__,}efi_call_virt: + * + * * arch_efi_call_virt_setup + * + * Sets up the environment for the call (e.g. switching page tables, + * allowing kernel-mode use of floating point, if required). + * + * * arch_efi_call_virt + * + * Performs the call. The last expression in the macro must be the call + * itself, allowing the logic to be shared by the void and non-void + * cases. + * + * * arch_efi_call_virt_teardown + * + * Restores the usual kernel environment once the call has returned. + */ + +#ifndef efi_call_virt +#define efi_call_virt(f, args...) \ +({ \ + efi_status_t __s; \ + arch_efi_call_virt_setup(); \ + __s = arch_efi_call_virt(f, args); \ + arch_efi_call_virt_teardown(); \ + __s; \ +}) +#endif + +#ifndef __efi_call_virt +#define __efi_call_virt(f, args...) \ +({ \ + arch_efi_call_virt_setup(); \ + arch_efi_call_virt(f, args); \ + arch_efi_call_virt_teardown(); \ +}) +#endif + +/* * According to section 7.1 of the UEFI spec, Runtime Services are not fully * reentrant, and there are particular combinations of calls that need to be * serialized. (source: UEFI Specification v2.4A) -- 2.7.3