From patchwork Mon Feb 8 13:55:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Trond Myklebust X-Patchwork-Id: 12075479 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=-19.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 A73D7C433E9 for ; Mon, 8 Feb 2021 13:57:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 63BD064E16 for ; Mon, 8 Feb 2021 13:57:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230386AbhBHN4o (ORCPT ); Mon, 8 Feb 2021 08:56:44 -0500 Received: from mail.kernel.org ([198.145.29.99]:36836 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231704AbhBHN4c (ORCPT ); Mon, 8 Feb 2021 08:56:32 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8622464E4F; Mon, 8 Feb 2021 13:55:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612792549; bh=KgjE87lOd8x6hjJA30x57vQAmDl5ZJxJhOVvaJ9dOB0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QVV8ut8CLaIcY/Q5lBiWdcEVIn79tXXq+x8DlsHNMYyB9yZpqDS9V4lA45c92Gbr4 xVDM/QxJum/uTPXXTyX7SacTb1MNY4oEexhRiQuE6UOSZkFtNo/qrGqDHjKQyRKFZL qqwU314/Pw/Io8ba+TpXF6cwCors0pxFU5HJI4IyITJ0mvqjoCXktocozxapassCgj 8rpTlICs679w/VMpXfNtYcje37hdiz0KBw7R39zxeab9mNnPCJiejZfJpx0+c5knxJ PDfIaF1L0Jud64XzZ4KbJGLIGiDLMdXbu5JeEEdxrUmk2PL3daCZAhoHLyqm2Rw9ia fprpNGzLlcW3g== From: trondmy@kernel.org To: Anna Schumaker Cc: linux-nfs@vger.kernel.org Subject: [PATCH 2/3] NFS: Optimise sparse writes past the end of file Date: Mon, 8 Feb 2021 08:55:46 -0500 Message-Id: <20210208135547.27153-2-trondmy@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210208135547.27153-1-trondmy@kernel.org> References: <20210208135547.27153-1-trondmy@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Trond Myklebust If we're doing a write, and the entire page lies beyond the end-of-file, then we can assume the write can be extended to cover the beginning of the page, since we know the data in that region will be all zeros. Signed-off-by: Trond Myklebust --- fs/nfs/file.c | 4 +--- fs/nfs/write.c | 20 ++++++++++++-------- 2 files changed, 13 insertions(+), 11 deletions(-) diff --git a/fs/nfs/file.c b/fs/nfs/file.c index d02a63af9c15..02795a01c7ef 100644 --- a/fs/nfs/file.c +++ b/fs/nfs/file.c @@ -626,13 +626,11 @@ ssize_t nfs_file_write(struct kiocb *iocb, struct iov_iter *from) /* * O_APPEND implies that we must revalidate the file length. */ - if (iocb->ki_flags & IOCB_APPEND) { + if (iocb->ki_flags & IOCB_APPEND || iocb->ki_pos > i_size_read(inode)) { result = nfs_revalidate_file_size(inode, file); if (result) goto out; } - if (iocb->ki_pos > i_size_read(inode)) - nfs_revalidate_mapping(inode, file->f_mapping); since = filemap_sample_wb_err(file->f_mapping); nfs_start_io_write(inode); diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 639c34fec04a..6193350356a8 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -1278,19 +1278,21 @@ bool nfs_ctx_key_to_expire(struct nfs_open_context *ctx, struct inode *inode) * the PageUptodate() flag. In this case, we will need to turn off * write optimisations that depend on the page contents being correct. */ -static bool nfs_write_pageuptodate(struct page *page, struct inode *inode) +static bool nfs_write_pageuptodate(struct page *page, struct inode *inode, + unsigned int pagelen) { struct nfs_inode *nfsi = NFS_I(inode); if (nfs_have_delegated_attributes(inode)) goto out; - if (nfsi->cache_validity & NFS_INO_REVAL_PAGECACHE) + if (nfsi->cache_validity & + (NFS_INO_REVAL_PAGECACHE | NFS_INO_INVALID_SIZE)) return false; smp_rmb(); - if (test_bit(NFS_INO_INVALIDATING, &nfsi->flags)) + if (test_bit(NFS_INO_INVALIDATING, &nfsi->flags) && pagelen != 0) return false; out: - if (nfsi->cache_validity & NFS_INO_INVALID_DATA) + if (nfsi->cache_validity & NFS_INO_INVALID_DATA && pagelen != 0) return false; return PageUptodate(page) != 0; } @@ -1310,7 +1312,8 @@ is_whole_file_wrlock(struct file_lock *fl) * If the file is opened for synchronous writes then we can just skip the rest * of the checks. */ -static int nfs_can_extend_write(struct file *file, struct page *page, struct inode *inode) +static int nfs_can_extend_write(struct file *file, struct page *page, + struct inode *inode, unsigned int pagelen) { int ret; struct file_lock_context *flctx = inode->i_flctx; @@ -1318,7 +1321,7 @@ static int nfs_can_extend_write(struct file *file, struct page *page, struct ino if (file->f_flags & O_DSYNC) return 0; - if (!nfs_write_pageuptodate(page, inode)) + if (!nfs_write_pageuptodate(page, inode, pagelen)) return 0; if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) return 1; @@ -1356,6 +1359,7 @@ int nfs_updatepage(struct file *file, struct page *page, struct nfs_open_context *ctx = nfs_file_open_context(file); struct address_space *mapping = page_file_mapping(page); struct inode *inode = mapping->host; + unsigned int pagelen = nfs_page_length(page); int status = 0; nfs_inc_stats(inode, NFSIOS_VFSUPDATEPAGE); @@ -1366,8 +1370,8 @@ int nfs_updatepage(struct file *file, struct page *page, if (!count) goto out; - if (nfs_can_extend_write(file, page, inode)) { - count = max(count + offset, nfs_page_length(page)); + if (nfs_can_extend_write(file, page, inode, pagelen)) { + count = max(count + offset, pagelen); offset = 0; }