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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 9505CECE58D for ; Thu, 3 Oct 2019 17:06:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6BCAB20673 for ; Thu, 3 Oct 2019 17:06:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570122417; bh=lxArp3kU4HFZxrzSHItw74m76dcaz61ksoyl0nVuO+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=sl5xX8p+W8qhLgRw+Egqomw3jmll4j+qpjfhgSpGJGTX3TIjQne08YMLBuFzJZch4 TtthenAXWZ8kCii+a5Ce1s673GIcKlNk1mEbEsnTWrgeCEWDpiqxPtX6//Pg3noz0K qV35ueR/HobRsbzHtq41avWv6yFEamvzhMM2q5jc= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404561AbfJCQhY (ORCPT ); Thu, 3 Oct 2019 12:37:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:46690 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2404549AbfJCQhU (ORCPT ); Thu, 3 Oct 2019 12:37:20 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D6A34215EA; Thu, 3 Oct 2019 16:37:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570120640; bh=lxArp3kU4HFZxrzSHItw74m76dcaz61ksoyl0nVuO+Y=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZZdjzL/jtDlmWacfTtqVnY75xbOLvuLvZ+7/8IUz/E+9RRUVLIkXtsGtVh1UW0r8d s8uX5ynw1SAMidi7iCkokdKq0yO76Hy1p5Zmpc7vvJb/ev7V5sTsglG+JE3RiFMH8d JeTscCmncwV+0ELLTrAPgrwhfoNeg2CnOafGKqZc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Amir Goldstein , Boaz Harrosh , Jan Kara , "Darrick J. Wong" Subject: [PATCH 5.2 298/313] mm: Handle MADV_WILLNEED through vfs_fadvise() Date: Thu, 3 Oct 2019 17:54:36 +0200 Message-Id: <20191003154602.510522173@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154533.590915454@linuxfoundation.org> References: <20191003154533.590915454@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jan Kara commit 692fe62433d4ca47605b39f7c416efd6679ba694 upstream. Currently handling of MADV_WILLNEED hint calls directly into readahead code. Handle it by calling vfs_fadvise() instead so that filesystem can use its ->fadvise() callback to acquire necessary locks or otherwise prepare for the request. Suggested-by: Amir Goldstein Reviewed-by: Boaz Harrosh CC: stable@vger.kernel.org Signed-off-by: Jan Kara Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong Signed-off-by: Greg Kroah-Hartman --- mm/madvise.c | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) --- a/mm/madvise.c +++ b/mm/madvise.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -275,6 +276,7 @@ static long madvise_willneed(struct vm_a unsigned long start, unsigned long end) { struct file *file = vma->vm_file; + loff_t offset; *prev = vma; #ifdef CONFIG_SWAP @@ -298,12 +300,20 @@ static long madvise_willneed(struct vm_a return 0; } - start = ((start - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; - if (end > vma->vm_end) - end = vma->vm_end; - end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff; - - force_page_cache_readahead(file->f_mapping, file, start, end - start); + /* + * Filesystem's fadvise may need to take various locks. We need to + * explicitly grab a reference because the vma (and hence the + * vma's reference to the file) can go away as soon as we drop + * mmap_sem. + */ + *prev = NULL; /* tell sys_madvise we drop mmap_sem */ + get_file(file); + up_read(¤t->mm->mmap_sem); + offset = (loff_t)(start - vma->vm_start) + + ((loff_t)vma->vm_pgoff << PAGE_SHIFT); + vfs_fadvise(file, offset, end - start, POSIX_FADV_WILLNEED); + fput(file); + down_read(¤t->mm->mmap_sem); return 0; }