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=-12.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, UNPARSEABLE_RELAY,USER_AGENT_GIT autolearn=ham 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 2280DC433DF for ; Tue, 18 Aug 2020 15:55:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ED6D22080C for ; Tue, 18 Aug 2020 15:55:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="KwOZWN5m" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728160AbgHRPzk (ORCPT ); Tue, 18 Aug 2020 11:55:40 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:40658 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728193AbgHRPr2 (ORCPT ); Tue, 18 Aug 2020 11:47:28 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 07IFSPYJ006850; Tue, 18 Aug 2020 15:47:24 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=corp-2020-01-29; bh=woaSbfOB/Qmr2EOwVWJ2i+ae6OF0n03FE+3J5rEFxO8=; b=KwOZWN5m1hLeNUmJrg23h116swkfloDRdX6TZ1Cj4B9jZyZuSmzD1OsUFLDexBhzdunJ 6puD5NT7gcbmk/q9kvis4bdqV/4F9IAAngDiN+9FMdJLhKIjsZpLlYb+gepR8e6pIZah g4bvW8nUn0Grpu30ML6oB9qdAyn0fXnepWWFCxKtZ5qzRm7X1Dp6mOcEe1pcITz2ojOR 7MxzH+Wnh6ujwu2UNcDKtrgYRuvKHnANm/YEiPWCxrCz1Zi8t8piTNji4U3O0Y8cgsSr IzWDW0jERU8bIhOymlW1USNHP/BwHiI8ljQ1lWl5JKp0s0tWX1vS3cYs7y4tV2Wk4V9D 7A== Received: from userp3030.oracle.com (userp3030.oracle.com [156.151.31.80]) by userp2130.oracle.com with ESMTP id 32x74r5q62-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 18 Aug 2020 15:47:24 +0000 Received: from pps.filterd (userp3030.oracle.com [127.0.0.1]) by userp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 07IFYuP7129633; Tue, 18 Aug 2020 15:47:24 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by userp3030.oracle.com with ESMTP id 32xsmxd0b1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 18 Aug 2020 15:47:24 +0000 Received: from abhmp0001.oracle.com (abhmp0001.oracle.com [141.146.116.7]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 07IFlNaM011736; Tue, 18 Aug 2020 15:47:23 GMT Received: from revolver.jebus.ca (/23.233.25.87) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 18 Aug 2020 08:47:23 -0700 From: "Liam R. Howlett" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Liam.Howlett@Oracle.com Subject: [PATCH 2/2] mm/mmap: Add inline munmap_vma_range() for code readability Date: Tue, 18 Aug 2020 11:47:07 -0400 Message-Id: <20200818154707.2515169-2-Liam.Howlett@Oracle.com> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200818154707.2515169-1-Liam.Howlett@Oracle.com> References: <20200818154707.2515169-1-Liam.Howlett@Oracle.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9716 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 malwarescore=0 spamscore=0 bulkscore=0 mlxlogscore=999 phishscore=0 mlxscore=0 suspectscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008180112 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9716 signatures=668679 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 impostorscore=0 mlxlogscore=999 priorityscore=1501 phishscore=0 spamscore=0 mlxscore=0 adultscore=0 suspectscore=0 lowpriorityscore=0 bulkscore=0 malwarescore=0 clxscore=1015 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2008180112 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are two locations that have a block of code for munmapping a vma range. Change those two locations to use a function and add meaningful comments about what happens to the arguments, which was unclear in the previous code. Signed-off-by: Liam R. Howlett --- mm/mmap.c | 48 +++++++++++++++++++++++++++++++++--------------- 1 file changed, 33 insertions(+), 15 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 6026353035966..b59b4e5889b5c 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -577,6 +577,33 @@ static inline struct vm_area_struct *vma_next(struct mm_struct *mm, return vma->vm_next; } + +/* + * munmap_vma_range() - munmap VMAs that overlap a range. + * @mm: The mm struct + * @start: The start of the range. + * @len: The length of the range. + * @pprev: pointer to the pointer that will be set to previous vm_area_struct + * @rb_link: the rb_node + * @rb_parent: the parent rb_node + * + * Find all the vm_area_struct that overlap from @start to + * @end and munmap them. Set @pprev to the previous vm_area_struct. + * + * Returns: -ENOMEM on munmap failure or 0 on success. + */ +static inline int +munmap_vma_range(struct mm_struct *mm, unsigned long start, unsigned long len, + struct vm_area_struct **pprev, struct rb_node ***link, + struct rb_node **parent, struct list_head *uf) +{ + + while (find_vma_links(mm, start, start + len, pprev, link, parent)) + if (do_munmap(mm, start, len, uf)) + return -ENOMEM; + + return 0; +} static unsigned long count_vma_pages_range(struct mm_struct *mm, unsigned long addr, unsigned long end) { @@ -1724,13 +1751,9 @@ unsigned long mmap_region(struct file *file, unsigned long addr, return -ENOMEM; } - /* Clear old maps */ - while (find_vma_links(mm, addr, addr + len, &prev, &rb_link, - &rb_parent)) { - if (do_munmap(mm, addr, len, uf)) - return -ENOMEM; - } - + /* Clear old maps, set up prev, rb_link, rb_parent, and uf */ + if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf)) + return -ENOMEM; /* * Private writable mapping: check memory availability */ @@ -3056,14 +3079,9 @@ static int do_brk_flags(unsigned long addr, unsigned long len, unsigned long fla if (error) return error; - /* - * Clear old maps. this also does some error checking for us - */ - while (find_vma_links(mm, addr, addr + len, &prev, &rb_link, - &rb_parent)) { - if (do_munmap(mm, addr, len, uf)) - return -ENOMEM; - } + /* Clear old maps, set up prev, rb_link, rb_parent, and uf */ + if (munmap_vma_range(mm, addr, len, &prev, &rb_link, &rb_parent, uf)) + return -ENOMEM; /* Check against address space limits *after* clearing old maps... */ if (!may_expand_vm(mm, flags, len >> PAGE_SHIFT)) -- 2.28.0