From patchwork Fri Aug 30 00:44:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Darrick J. Wong" X-Patchwork-Id: 11122767 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DFD261399 for ; Fri, 30 Aug 2019 00:44:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB67C21726 for ; Fri, 30 Aug 2019 00:44:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="MbkqC9O6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727478AbfH3AoO (ORCPT ); Thu, 29 Aug 2019 20:44:14 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:52388 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727065AbfH3AoN (ORCPT ); Thu, 29 Aug 2019 20:44:13 -0400 Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7U0hxMx138090; Fri, 30 Aug 2019 00:44:10 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=date : from : to : cc : subject : message-id : references : mime-version : content-type : content-transfer-encoding : in-reply-to; s=corp-2019-08-05; bh=MSx/UmW0PNs1mTI2NqYCyWn3va9Y/drJGyZLPVqW8+w=; b=MbkqC9O6UWHPmpFTztLf8UrKZ5h1TLai+GEqWZl+S9GnFWbr1qqrkkKhRz9Mbw4u2fAr SUdl6DHVvTqdTuxRUfJzNp6KPosDJ3n/KAYG5NH+YQPCrF4DSa7fgrCha4UmitypBI96 SqBn7y3u+kwcY1nsZFo8WXyUlK0lY7cRr2VHr145DjwXV3nY2MjsQSLgegdc2Apdpt9H dMRdNpomwLHiS6viCrACTkQ4a+CVo4Yj37rw8dZCmJ2TuRl74ThdSRpOUuJCclc3jX9L ErqIvBEW/58CJM0TD4UMTBDtYW7uID6AbtgSLy3IcAL8YsCHq8b+zIARO49wzpbfLTxf yA== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2120.oracle.com with ESMTP id 2upsac81ke-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 30 Aug 2019 00:44:10 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x7U0hQiE143030; Fri, 30 Aug 2019 00:44:09 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3030.oracle.com with ESMTP id 2uphaufdss-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 30 Aug 2019 00:44:09 +0000 Received: from abhmp0008.oracle.com (abhmp0008.oracle.com [141.146.116.14]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x7U0i8GU027065; Fri, 30 Aug 2019 00:44:08 GMT Received: from localhost (/10.145.178.11) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 29 Aug 2019 17:44:07 -0700 Date: Thu, 29 Aug 2019 17:44:07 -0700 From: "Darrick J. Wong" To: andreas.gruenbacher@gmail.com Cc: xfs , viro@zeniv.linux.org.uk, linux-fsdevel , fstests Subject: [RFC PATCH] generic: test splice() with pipes Message-ID: <20190830004407.GA5340@magnolia> References: <20190829161155.GA5360@magnolia> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190829161155.GA5360@magnolia> User-Agent: Mutt/1.9.4 (2018-02-28) X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9364 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908300004 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9364 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1906280000 definitions=main-1908300005 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org From: Darrick J. Wong Andreas Grünbacher reports that on the two filesystems that support iomap directio, it's possible for splice() to return -EAGAIN (instead of a short splice) if the pipe being written to has less space available in its pipe buffers than the length supplied by the calling process. This is a regression test to check for correct operation. XXX Andreas: Since you wrote the C reproducer, can you send me the proper copyright and author attribution statement for the C program? Signed-off-by: Darrick J. Wong --- .gitignore | 1 src/Makefile | 2 - src/splice-test.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++ tests/generic/720 | 41 ++++++++++++ tests/generic/720.out | 7 ++ tests/generic/group | 1 6 files changed, 224 insertions(+), 1 deletion(-) create mode 100644 src/splice-test.c create mode 100755 tests/generic/720 create mode 100644 tests/generic/720.out diff --git a/.gitignore b/.gitignore index c8c815f9..26d4da11 100644 --- a/.gitignore +++ b/.gitignore @@ -112,6 +112,7 @@ /src/runas /src/seek_copy_test /src/seek_sanity_test +/src/splice-test /src/stale_handle /src/stat_test /src/swapon diff --git a/src/Makefile b/src/Makefile index c4fcf370..2920dfb1 100644 --- a/src/Makefile +++ b/src/Makefile @@ -28,7 +28,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ attr-list-by-handle-cursor-test listxattr dio-interleaved t_dir_type \ dio-invalidate-cache stat_test t_encrypted_d_revalidate \ attr_replace_test swapon mkswap t_attr_corruption t_open_tmpfiles \ - fscrypt-crypt-util bulkstat_null_ocount + fscrypt-crypt-util bulkstat_null_ocount splice-test SUBDIRS = log-writes perf diff --git a/src/splice-test.c b/src/splice-test.c new file mode 100644 index 00000000..d3c12075 --- /dev/null +++ b/src/splice-test.c @@ -0,0 +1,173 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2019 ????????????????????????????? + * Author: + * + * Make sure that reading and writing to a pipe via splice. + */ +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include + +#define SECTOR_SIZE 512 +#define BUFFER_SIZE (150 * SECTOR_SIZE) + +void read_from_pipe(int fd, const char *filename, size_t size) +{ + char buffer[SECTOR_SIZE]; + size_t sz; + ssize_t ret; + + while (size) { + sz = size; + if (sz > sizeof buffer) + sz = sizeof buffer; + ret = read(fd, buffer, sz); + if (ret < 0) + err(1, "read: %s", filename); + if (ret == 0) { + fprintf(stderr, "read: %s: unexpected EOF\n", filename); + exit(1); + } + size -= sz; + } +} + +void do_splice1(int fd, const char *filename, size_t size) +{ + bool retried = false; + int pipefd[2]; + + if (pipe(pipefd) == -1) + err(1, "pipe"); + while (size) { + ssize_t spliced; + + spliced = splice(fd, NULL, pipefd[1], NULL, size, SPLICE_F_MOVE); + if (spliced == -1) { + if (errno == EAGAIN && !retried) { + retried = true; + fprintf(stderr, "retrying splice\n"); + sleep(1); + continue; + } + err(1, "splice"); + } + read_from_pipe(pipefd[0], filename, spliced); + size -= spliced; + } + close(pipefd[0]); + close(pipefd[1]); +} + +void do_splice2(int fd, const char *filename, size_t size) +{ + bool retried = false; + int pipefd[2]; + int pid; + + if (pipe(pipefd) == -1) + err(1, "pipe"); + + pid = fork(); + if (pid == 0) { + close(pipefd[1]); + read_from_pipe(pipefd[0], filename, size); + exit(0); + } else { + close(pipefd[0]); + while (size) { + ssize_t spliced; + + spliced = splice(fd, NULL, pipefd[1], NULL, size, SPLICE_F_MOVE); + if (spliced == -1) { + if (errno == EAGAIN && !retried) { + retried = true; + fprintf(stderr, "retrying splice\n"); + sleep(1); + continue; + } + err(1, "splice"); + } + size -= spliced; + } + close(pipefd[1]); + waitpid(pid, NULL, 0); + } +} + +void usage(const char *argv0) +{ + fprintf(stderr, "USAGE: %s [-rd] {filename}\n", basename(argv0)); + exit(2); +} + +int main(int argc, char *argv[]) +{ + void (*do_splice)(int fd, const char *filename, size_t size); + const char *filename; + char *buffer; + int opt, open_flags, fd; + ssize_t ret; + + do_splice = do_splice1; + open_flags = O_CREAT | O_TRUNC | O_RDWR | O_DIRECT; + + while ((opt = getopt(argc, argv, "rd")) != -1) { + switch(opt) { + case 'r': + do_splice = do_splice2; + break; + case 'd': + open_flags &= ~O_DIRECT; + break; + default: /* '?' */ + usage(argv[0]); + } + } + + if (optind >= argc) + usage(argv[0]); + filename = argv[optind]; + + printf("%s reader %s O_DIRECT\n", + do_splice == do_splice1 ? "sequential" : "concurrent", + (open_flags & O_DIRECT) ? "with" : "without"); + + buffer = aligned_alloc(SECTOR_SIZE, BUFFER_SIZE); + if (buffer == NULL) + err(1, "aligned_alloc"); + + fd = open(filename, open_flags, 0666); + if (fd == -1) + err(1, "open: %s", filename); + + memset(buffer, 'x', BUFFER_SIZE); + ret = write(fd, buffer, BUFFER_SIZE); + if (ret < 0) + err(1, "write: %s", filename); + if (ret != BUFFER_SIZE) { + fprintf(stderr, "%s: short write\n", filename); + exit(1); + } + + ret = lseek(fd, 0, SEEK_SET); + if (ret != 0) + err(1, "lseek: %s", filename); + + do_splice(fd, filename, BUFFER_SIZE); + + if (unlink(filename) == -1) + err(1, "unlink: %s", filename); + + return 0; +} diff --git a/tests/generic/720 b/tests/generic/720 new file mode 100755 index 00000000..b7f09c40 --- /dev/null +++ b/tests/generic/720 @@ -0,0 +1,41 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0-or-later +# Copyright (c) 2019, Oracle and/or its affiliates. All Rights Reserved. +# +# FS QA Test No. 720 +# +# Test using splice() to read from pipes. + +seq=`basename $0` +seqres=$RESULT_DIR/$seq +echo "QA output created by $seq" + +here=`pwd` +tmp=/tmp/$$ +status=1 # failure is the default! +trap "_cleanup; exit \$status" 0 1 2 3 15 + +_cleanup() +{ + cd / + rm -f $TEST_DIR/a +} + +# get standard environment, filters and checks +. ./common/rc + +# real QA test starts here +_supported_os Linux +_supported_fs generic +_require_test + +rm -f $seqres.full + +src/splice-test -r $TEST_DIR/a +src/splice-test -rd $TEST_DIR/a +src/splice-test $TEST_DIR/a +src/splice-test -d $TEST_DIR/a + +# success, all done +status=0 +exit diff --git a/tests/generic/720.out b/tests/generic/720.out new file mode 100644 index 00000000..b0fc9935 --- /dev/null +++ b/tests/generic/720.out @@ -0,0 +1,7 @@ +QA output created by 720 +concurrent reader with O_DIRECT +concurrent reader with O_DIRECT +concurrent reader without O_DIRECT +concurrent reader without O_DIRECT +sequential reader with O_DIRECT +sequential reader without O_DIRECT diff --git a/tests/generic/group b/tests/generic/group index cd418106..f75d4e60 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -569,3 +569,4 @@ 564 auto quick copy_range 565 auto quick copy_range 719 auto quick quota metadata +720 auto quick rw pipe splice