From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64323C4BA06 for ; Tue, 25 Feb 2020 23:26:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4031D24683 for ; Tue, 25 Feb 2020 23:26:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730072AbgBYX0Q (ORCPT ); Tue, 25 Feb 2020 18:26:16 -0500 Received: from Galois.linutronix.de ([193.142.43.55]:55700 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730008AbgBYX0N (ORCPT ); Tue, 25 Feb 2020 18:26:13 -0500 Received: from p5de0bf0b.dip0.t-ipconnect.de ([93.224.191.11] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtpsa (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1j6jaG-0004es-RT; Wed, 26 Feb 2020 00:25:49 +0100 Received: from nanos.tec.linutronix.de (localhost [IPv6:::1]) by nanos.tec.linutronix.de (Postfix) with ESMTP id B83F110408E; Wed, 26 Feb 2020 00:25:37 +0100 (CET) Message-Id: <20200225222648.772492410@linutronix.de> User-Agent: quilt/0.65 Date: Tue, 25 Feb 2020 23:16:12 +0100 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Steven Rostedt , Brian Gerst , Juergen Gross , Paolo Bonzini , Arnd Bergmann Subject: [patch 06/24] x86/idtentry: Provide macros to define/declare IDT entry points References: <20200225221606.511535280@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Provide DECLARE/DEFINE_IDTENTRY() macros. DEFINE_IDTENTRY() provides a wrapper which acts as the function definition. The exception handler body is just appended to it with curly brackets. The entry point is marked notrace/noprobe so that irq tracing and the enter_from_user_mode() can be moved into the C-entry point. As all C-entries use the same macro (or a later variant) the necessary entry handling can be implemented at one central place. DECLARE_IDTENTRY() provides the function prototypes: - The C entry point cfunc - The ASM entry point asm_cfunc - The XEN/PV entry point xen_asm_cfunc They all follow the same naming convention. When included from ASM code DECLARE_IDTENTRY() is a macro which emits the low level entry point in assembly by instantiating idtentry. IDTENTRY is the simplest variant which just has a pt_regs argument. It's going to be used for all exceptions which have no error code. Signed-off-by: Thomas Gleixner --- arch/x86/entry/entry_32.S | 6 +++ arch/x86/entry/entry_64.S | 6 +++ arch/x86/include/asm/idtentry.h | 79 ++++++++++++++++++++++++++++++++++++++++ arch/x86/include/asm/traps.h | 2 - 4 files changed, 92 insertions(+), 1 deletion(-) --- a/arch/x86/entry/entry_32.S +++ b/arch/x86/entry/entry_32.S @@ -769,6 +769,12 @@ SYM_CODE_END(\asmsym) .endm /* + * Include the defines which emit the idt entries which are shared + * shared between 32 and 64 bit. + */ +#include + +/* * %eax: prev task * %edx: next task */ --- a/arch/x86/entry/entry_64.S +++ b/arch/x86/entry/entry_64.S @@ -688,6 +688,12 @@ SYM_CODE_END(\asmsym) .endm /* + * Include the defines which emit the idt entries which are shared + * shared between 32 and 64 bit. + */ +#include + +/* * Interrupt entry helper function. * * Entry runs with interrupts off. Stack layout at entry: --- /dev/null +++ b/arch/x86/include/asm/idtentry.h @@ -0,0 +1,79 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_X86_IDTENTRY_H +#define _ASM_X86_IDTENTRY_H + +/* Interrupts/Exceptions */ +#include + +#ifndef __ASSEMBLY__ + +/** + * idtentry_enter - Handle state tracking on idtentry + * @regs: Pointer to pt_regs of interrupted context + * + * Place holder for now. + */ +static __always_inline void idtentry_enter(struct pt_regs *regs) +{ +} + +/** + * idtentry_exit - Prepare returning to low level ASM code + * + * Place holder for now. + */ +static __always_inline void idtentry_exit(struct pt_regs *regs) +{ +} + +/** + * DECLARE_IDTENTRY - Declare functions for simple IDT entry points + * No error code pushed by hardware + * @vector: Vector number (ignored for C) + * @func: Function name of the entry point + * + * Declares three functions: + * - The ASM entry point: asm_##func + * - The XEN PV trap entry point: xen_##func (maybe unused) + * - The C handler called from the ASM entry point + */ +#define DECLARE_IDTENTRY(vector, func) \ + asmlinkage void asm_##func(void); \ + asmlinkage void xen_asm_##func(void); \ + __visible void func(struct pt_regs *regs) + +/** + * DEFINE_IDTENTRY - Emit code for simple IDT entry points + * @func: Function name of the entry point + * + * @func is called from ASM entry code with interrupts disabled. + * + * The macro is written so it acts as function definition. Append the + * body with a pair of curly brackets. + * + * idtentry_enter() contains common code which has to be invoked before + * arbitrary code in the body. idtentry_exit() contains common code + * which has to run before returning to the low level assembly code. + */ +#define DEFINE_IDTENTRY(func) \ +static __always_inline void __##func(struct pt_regs *regs); \ + \ +__visible notrace void func(struct pt_regs *regs) \ +{ \ + idtentry_enter(regs); \ + __##func (regs); \ + idtentry_exit(regs); \ +} \ +NOKPROBE_SYMBOL(func); \ + \ +static __always_inline void __##func(struct pt_regs *regs) + +#else /* !__ASSEMBLY__ */ + +/* Defines for ASM code to construct the IDT entries */ +#define DECLARE_IDTENTRY(vector, func) \ + idtentry vector asm_##func func has_error_code=0 + +#endif /* __ASSEMBLY__ */ + +#endif --- a/arch/x86/include/asm/traps.h +++ b/arch/x86/include/asm/traps.h @@ -6,8 +6,8 @@ #include #include +#include #include /* TRAP_TRACE, ... */ -#include #define dotraplinkage __visible