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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 C7749C2B9F7 for ; Wed, 26 May 2021 05:02:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A193B610CB for ; Wed, 26 May 2021 05:02:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231174AbhEZFDc (ORCPT ); Wed, 26 May 2021 01:03:32 -0400 Received: from mga09.intel.com ([134.134.136.24]:29575 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229685AbhEZFDc (ORCPT ); Wed, 26 May 2021 01:03:32 -0400 IronPort-SDR: UAFVu22d7VQTeTvh4TAUGMfUz4+pEIAG+56VJD/HBdAKvebqQqzzEmrnZiuAmwxtuYV5KwFiYb CbwQi7k/zAFA== X-IronPort-AV: E=McAfee;i="6200,9189,9995"; a="202395910" X-IronPort-AV: E=Sophos;i="5.82,330,1613462400"; d="scan'208";a="202395910" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 May 2021 22:01:59 -0700 IronPort-SDR: zQkz1Y67YopzocW+inNWA3lREcKog8YlC7QCgQlRPgw8zTcoWfhNGL5ORVnUkuzQgO7nLoXXt1 qTfB7hcztefw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,330,1613462400"; d="scan'208";a="479700258" Received: from shbuild999.sh.intel.com ([10.239.147.94]) by fmsmga002.fm.intel.com with ESMTP; 25 May 2021 22:01:50 -0700 From: Feng Tang To: linux-mm@kvack.org, Andrew Morton , Michal Hocko , David Rientjes , Dave Hansen , Ben Widawsky Cc: linux-kernel@vger.kernel.org, Andrea Arcangeli , Mel Gorman , Mike Kravetz , Randy Dunlap , Vlastimil Babka , Andi Kleen , Dan Williams , ying.huang@intel.com, Feng Tang Subject: [PATCH v1 2/4] mm/mempolicy: unify the preprocessing for mbind and set_mempolicy Date: Wed, 26 May 2021 13:01:40 +0800 Message-Id: <1622005302-23027-3-git-send-email-feng.tang@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1622005302-23027-1-git-send-email-feng.tang@intel.com> References: <1622005302-23027-1-git-send-email-feng.tang@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently the kernel_mbind() and kernel_set_mempolicy() do almost the same operation for parameter sanity check and preprocessing. Add a helper function to unify the code to reduce the redundancy, and make it easier for changing the pre-processing code in future. [thanks to David Rientjes for suggesting using helper function instead of macro] Signed-off-by: Feng Tang --- mm/mempolicy.c | 43 ++++++++++++++++++++++++------------------- 1 file changed, 24 insertions(+), 19 deletions(-) diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 1964cca..2830bb8 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -1460,6 +1460,20 @@ static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; } +static inline int mpol_pre_process(int *mode, const unsigned long __user *nmask, unsigned long maxnode, nodemask_t *nodes, unsigned short *flags) +{ + int ret; + + *flags = *mode & MPOL_MODE_FLAGS; + *mode &= ~MPOL_MODE_FLAGS; + if ((unsigned int)(*mode) >= MPOL_MAX) + return -EINVAL; + if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES)) + return -EINVAL; + ret = get_nodes(nodes, nmask, maxnode); + return ret; +} + static long kernel_mbind(unsigned long start, unsigned long len, unsigned long mode, const unsigned long __user *nmask, unsigned long maxnode, unsigned int flags) @@ -1467,19 +1481,14 @@ static long kernel_mbind(unsigned long start, unsigned long len, nodemask_t nodes; int err; unsigned short mode_flags; + int lmode = mode; - start = untagged_addr(start); - mode_flags = mode & MPOL_MODE_FLAGS; - mode &= ~MPOL_MODE_FLAGS; - if (mode >= MPOL_MAX) - return -EINVAL; - if ((mode_flags & MPOL_F_STATIC_NODES) && - (mode_flags & MPOL_F_RELATIVE_NODES)) - return -EINVAL; - err = get_nodes(&nodes, nmask, maxnode); + err = mpol_pre_process(&lmode, nmask, maxnode, &nodes, &mode_flags); if (err) return err; - return do_mbind(start, len, mode, mode_flags, &nodes, flags); + + start = untagged_addr(start); + return do_mbind(start, len, lmode, mode_flags, &nodes, flags); } SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, @@ -1495,18 +1504,14 @@ static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask, { int err; nodemask_t nodes; - unsigned short flags; + unsigned short mode_flags; + int lmode = mode; - flags = mode & MPOL_MODE_FLAGS; - mode &= ~MPOL_MODE_FLAGS; - if ((unsigned int)mode >= MPOL_MAX) - return -EINVAL; - if ((flags & MPOL_F_STATIC_NODES) && (flags & MPOL_F_RELATIVE_NODES)) - return -EINVAL; - err = get_nodes(&nodes, nmask, maxnode); + err = mpol_pre_process(&lmode, nmask, maxnode, &nodes, &mode_flags); if (err) return err; - return do_set_mempolicy(mode, flags, &nodes); + + return do_set_mempolicy(lmode, mode_flags, &nodes); } SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, -- 2.7.4