From patchwork Mon Jul 2 11:04:09 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Rutland X-Patchwork-Id: 140738 Delivered-To: patch@linaro.org Received: by 2002:a2e:9754:0:0:0:0:0 with SMTP id f20-v6csp3857500ljj; Mon, 2 Jul 2018 04:07:44 -0700 (PDT) X-Google-Smtp-Source: AAOMgpdL1VgDg96v8aLafmgFqxdIi98Fsuvt8VQHrQrrrQ9veIuz+cZM06P9D67gNuPqlNH2OV2s X-Received: by 2002:a62:9c17:: with SMTP id f23-v6mr15130280pfe.209.1530529664026; Mon, 02 Jul 2018 04:07:44 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1530529664; cv=none; d=google.com; s=arc-20160816; b=weCU7O5hSSFgAA8xaTcZUsxFztMcpMTppZzMdJSG/bRtkd9TRGO6/JQLlm6D+XLPCS 2lVx0OCrblPLtvU+6UWVFT1EKXBWTkZqtlo2PgUhNOV3O/JxjyzoFaT+2h3FTWC4FMLi lJKQt9mR0C+qoSOAgdinoj2M1qjFlH8ruJ74k3QadIHHuBAIlYc18c4qS7e6cs0rwtFi bOQKerJgZOu+lB2otYZvw6llJHexR6PnxSz4qrFC/NHQjHrtGMFf3Hn8mHD/phwXn3p4 KC2dpVT7abhUJPRJirWogN77XnziPX+rUsb+RF0ccpyM8OsPDrlE/YU1384f8MNzo/tR 7RBw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=QR6AYj0erSu4mrb/hQXJOFPO1fLRJozeG1ZhKnAPjDE=; b=r4kz2XTfAWilnhIQ4PbLXyMLsAYhHzSo7tQLyC4G9kmEFKLCGNDPaiWmDznkS56chi 4m/Zl/3k8IB5QfTjQWJI2GIAEmcXOUxEcx6T8c/vjpA7bcYP5pzN5ZiLYU2FxE3pwmP8 H26XsSpiryXm+jnH/QUF0pVArSpgGo/rToAs07r7Yzm9JFFFnWfzawCB+gsIhF0eHzFO rlZflpsIy7xaATgEu6xLCzQqGr1pYwsQ9EbKdcgNS3CvKEjsy5w9Hc1iDBkHU60A2XJ7 lzKTjlhtq3cSDJkW074fpCvxKAf2tWj/Wog+q3T7l/5ex2+/tUFDoj70cW1vs4b8Lhbk n2Jw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id a10-v6si15858487pls.480.2018.07.02.04.07.43; Mon, 02 Jul 2018 04:07:44 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965631AbeGBLHm (ORCPT + 31 others); Mon, 2 Jul 2018 07:07:42 -0400 Received: from foss.arm.com ([217.140.101.70]:57600 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1030389AbeGBLE7 (ORCPT ); Mon, 2 Jul 2018 07:04:59 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id F21A01529; Mon, 2 Jul 2018 04:04:58 -0700 (PDT) Received: from lakrids.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E1A3A3F5BA; Mon, 2 Jul 2018 04:04:56 -0700 (PDT) From: Mark Rutland To: linux-arm-kernel@lists.infradead.org, will.deacon@arm.com Cc: linux-kernel@vger.kernel.org, catalin.marinas@arm.com, dave.martin@arm.com, hch@infradead.org, james.morse@arm.com, linux@dominikbrodowski.net, linux-fsdevel@vger.kernel.org, marc.zyngier@arm.com, mark.rutland@arm.com, viro@zeniv.linux.org.uk Subject: [PATCHv4 13/19] kernel: add ksys_personality() Date: Mon, 2 Jul 2018 12:04:09 +0100 Message-Id: <20180702110415.10465-14-mark.rutland@arm.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20180702110415.10465-1-mark.rutland@arm.com> References: <20180702110415.10465-1-mark.rutland@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Using this helper allows us to avoid the in-kernel call to the sys_personality() syscall. The ksys_ prefix denotes that this function is meant as a drop-in replacement for the syscall. In particular, it uses the same calling convention as sys_personality(). Since ksys_personality is trivial, it is implemented directly in , as we do for ksys_close() and friends. This helper is necessary to enable conversion of arm64's syscall handling to use pt_regs wrappers. Signed-off-by: Mark Rutland Reviewed-by: Dominik Brodowski Cc: Al Viro Cc: Christoph Hellwig Cc: Dave Martin --- include/linux/syscalls.h | 11 +++++++++++ 1 file changed, 11 insertions(+) -- 2.11.0 diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index a368a68cb667..abfe12d8a9c5 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -80,6 +80,7 @@ union bpf_attr; #include #include #include +#include #include #ifdef CONFIG_ARCH_HAS_SYSCALL_WRAPPER @@ -1281,4 +1282,14 @@ static inline long ksys_truncate(const char __user *pathname, loff_t length) return do_sys_truncate(pathname, length); } +static inline unsigned int ksys_personality(unsigned int personality) +{ + unsigned int old = current->personality; + + if (personality != 0xffffffff) + set_personality(personality); + + return old; +} + #endif