From patchwork Mon Dec 15 05:26:55 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Omar Sandoval X-Patchwork-Id: 5490431 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 80D10BEEA8 for ; Mon, 15 Dec 2014 05:27:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 75D90209EB for ; Mon, 15 Dec 2014 05:27:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8EE65209E5 for ; Mon, 15 Dec 2014 05:27:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751382AbaLOF1e (ORCPT ); Mon, 15 Dec 2014 00:27:34 -0500 Received: from mail-pd0-f171.google.com ([209.85.192.171]:44905 "EHLO mail-pd0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750876AbaLOF10 (ORCPT ); Mon, 15 Dec 2014 00:27:26 -0500 Received: by mail-pd0-f171.google.com with SMTP id y13so10996837pdi.2 for ; Sun, 14 Dec 2014 21:27:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:in-reply-to:references; bh=xrOGVlakQej9NBaA4oGcypypzH5NxtWE+w551u+1r9g=; b=dEI+OAbgsYbCPCfeBqR1M+gtDAa6AvGpW0q85B2LDeh2nHf4dTqgaXJzwGEPMlqDio NVfEBUo3bl/KzeXiCO4ecIHiLD5s4UdZJvx0Fb7UREVs7aqI7RhawcukJeGaYYh7FoBr AnPN2SWT3MiA+Qg3e+OGD8y5tPtd9sbW0Pax3uXpiVA8UTr0kBsJnGOs2dJcou8cFTYN HNnFjTsizDa8oskSX65juMMGJ/IhvMLru1Ke8rdoHDLo1PbN2745n6wMYzkMY4vF6ScR 1DYAhBMYhgMf3lu4oBF5v0RZd5Kfuh71mHzWz6XTZBhiMwyZ7kTS9gtBPSnGrWH+ADhN lvxA== X-Gm-Message-State: ALoCoQlHpQoQlo2xiJjLlYs/NnUyZggNFpkwYIq5lKgBV6ZksayALh5IKceHzLD/iF3iEKxBTcjP X-Received: by 10.68.69.80 with SMTP id c16mr47719798pbu.125.1418621245856; Sun, 14 Dec 2014 21:27:25 -0800 (PST) Received: from mew.localdomain ([72.192.100.38]) by mx.google.com with ESMTPSA id f12sm7915174pdm.90.2014.12.14.21.27.23 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Sun, 14 Dec 2014 21:27:25 -0800 (PST) From: Omar Sandoval To: Alexander Viro , Andrew Morton , Trond Myklebust , Christoph Hellwig , David Sterba , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Omar Sandoval Subject: [PATCH 1/8] nfs: follow direct I/O write locking convention Date: Sun, 14 Dec 2014 21:26:55 -0800 Message-Id: <7561c096c7de603ac39fcfcff7bd2ec80589cae1.1418618044.git.osandov@osandov.com> X-Mailer: git-send-email 2.1.3 In-Reply-To: References: In-Reply-To: References: Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The generic callers of direct_IO lock i_mutex before doing a write. NFS doesn't use the generic write code, so it doesn't follow this convention. This is now a problem because the interface introduced for swap-over-NFS calls direct_IO for a write without holding i_mutex, but other implementations of direct_IO will expect to have it locked. Signed-off-by: Omar Sandoval --- fs/nfs/direct.c | 12 +++++------- fs/nfs/file.c | 8 ++++++-- 2 files changed, 11 insertions(+), 9 deletions(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index 10bf072..9402b96 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -906,17 +906,15 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter, if (!count) goto out; - mutex_lock(&inode->i_mutex); - result = nfs_sync_mapping(mapping); if (result) - goto out_unlock; + goto out; if (mapping->nrpages) { result = invalidate_inode_pages2_range(mapping, pos >> PAGE_CACHE_SHIFT, end); if (result) - goto out_unlock; + goto out; } task_io_account_write(count); @@ -924,7 +922,7 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter, result = -ENOMEM; dreq = nfs_direct_req_alloc(); if (!dreq) - goto out_unlock; + goto out; dreq->inode = inode; dreq->bytes_left = count; @@ -960,12 +958,12 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter, } } nfs_direct_req_release(dreq); + + mutex_lock(&inode->i_mutex); return result; out_release: nfs_direct_req_release(dreq); -out_unlock: - mutex_unlock(&inode->i_mutex); out: return result; } diff --git a/fs/nfs/file.c b/fs/nfs/file.c index 2ab6f00..8b80276 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -675,8 +675,12 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from) if (result) return result; - if (file->f_flags & O_DIRECT) - return nfs_file_direct_write(iocb, from, pos); + if (file->f_flags & O_DIRECT) { + mutex_lock(&inode->i_mutex); + result = nfs_file_direct_write(iocb, from, pos); + mutex_unlock(&inode->i_mutex); + return result; + } dprintk("NFS: write(%pD2, %zu@%Ld)\n", file, count, (long long) pos);