From patchwork Mon Sep 21 16:31:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 309387 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=-14.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 ABC8DC43465 for ; Mon, 21 Sep 2020 16:52:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6D9DA2076E for ; Mon, 21 Sep 2020 16:52:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600707121; bh=hcg0xITRDx7PJvaz4JYlC8n1jzqkFTy22dae6DGDrbI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zZbkwYOgpiFLG3ImydHd+aRYf6qccL/spaTJwW5XrUJQq7Yg0CcyvaG7OfWFsBHTt efQ4tGeKNn3ICpRndTqBB7xOuRriYk2L/YMhdjBASqHyOIBzgsGqKnbfaYCP5udiKJ 8SgLqgLITCRhVIDF5ZFuQQIq13xIsW/TTGoOZd/E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727937AbgIUQtw (ORCPT ); Mon, 21 Sep 2020 12:49:52 -0400 Received: from mail.kernel.org ([198.145.29.99]:57996 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728530AbgIUQtu (ORCPT ); Mon, 21 Sep 2020 12:49:50 -0400 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 781022388B; Mon, 21 Sep 2020 16:49:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600706990; bh=hcg0xITRDx7PJvaz4JYlC8n1jzqkFTy22dae6DGDrbI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=OMnhaE7xy7Cy24HbqAqdBPgFd3qSOkkaqBBmkzllNKY5ro5la/UYVwKHApQmkGKh+ edfyep4Lfy4MLRUFXodFawxmREtA5CKqjtEh7o8nwmLHZQcycFrrtEC4dfL+TodkR3 NS9l71m/9P85kTCgAIdJ7TY8HugdU9PgcWTmuaUI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gabriel Krisman Bertazi , Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 5.4 24/72] f2fs: Return EOF on unaligned end of file DIO read Date: Mon, 21 Sep 2020 18:31:03 +0200 Message-Id: <20200921163123.019424071@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200921163121.870386357@linuxfoundation.org> References: <20200921163121.870386357@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Gabriel Krisman Bertazi [ Upstream commit 20d0a107fb35f37578b919f62bd474d6d358d579 ] Reading past end of file returns EOF for aligned reads but -EINVAL for unaligned reads on f2fs. While documentation is not strict about this corner case, most filesystem returns EOF on this case, like iomap filesystems. This patch consolidates the behavior for f2fs, by making it return EOF(0). it can be verified by a read loop on a file that does a partial read before EOF (A file that doesn't end at an aligned address). The following code fails on an unaligned file on f2fs, but not on btrfs, ext4, and xfs. while (done < total) { ssize_t delta = pread(fd, buf + done, total - done, off + done); if (!delta) break; ... } It is arguable whether filesystems should actually return EOF or -EINVAL, but since iomap filesystems support it, and so does the original DIO code, it seems reasonable to consolidate on that. Signed-off-by: Gabriel Krisman Bertazi Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/data.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index ec9a1f9ce2dd6..68be334afc286 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2753,6 +2753,9 @@ static int check_direct_IO(struct inode *inode, struct iov_iter *iter, unsigned long align = offset | iov_iter_alignment(iter); struct block_device *bdev = inode->i_sb->s_bdev; + if (iov_iter_rw(iter) == READ && offset >= i_size_read(inode)) + return 1; + if (align & blocksize_mask) { if (bdev) blkbits = blksize_bits(bdev_logical_block_size(bdev));