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=-16.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 64F77C433B4 for ; Thu, 20 May 2021 16:59:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3D743613AD for ; Thu, 20 May 2021 16:59:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233897AbhETRAx (ORCPT ); Thu, 20 May 2021 13:00:53 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42681 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236007AbhETQ7J (ORCPT ); Thu, 20 May 2021 12:59:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1621529867; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=jiNHK+9IHPz+vdvTdOz9JPHJQDdbd56mScIln4jzHqs=; b=XQ5XRqWF57x/nWcIlyAWIgsSXTLbB3CtBLjeeWSfTihJjODUgRQJhCHNe1QUwO5VNrN4Zq JamgzAsk8xOkOdEOFDqRFJ7MQVZQLFHbp+hsj0weGhghPnCwzyuB0J2I4NjBpsRnKc2Zsj IYYejOz8oLBY2hQAnT97DVbrap9dEWU= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-295-iZ75VRpPNyC9jTNmSdn7NQ-1; Thu, 20 May 2021 12:57:44 -0400 X-MC-Unique: iZ75VRpPNyC9jTNmSdn7NQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B5ECF5B364 for ; Thu, 20 May 2021 16:57:43 +0000 (UTC) Received: from max.com (unknown [10.40.195.97]) by smtp.corp.redhat.com (Postfix) with ESMTP id EE20B1007625; Thu, 20 May 2021 16:57:42 +0000 (UTC) From: Andreas Gruenbacher To: fstests@vger.kernel.org Cc: Andreas Gruenbacher Subject: [PATCH v5] generic/637: Test page faults during read and write Date: Thu, 20 May 2021 18:57:41 +0200 Message-Id: <20210520165741.1607453-1-agruenba@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: fstests@vger.kernel.org Some filesystems have problems when the buffer passed to read or write is memory-mapped to the file being read from or written to and the buffer is faulted in during the read or write. (That's probably not a recommended use case, but it should work nevertheless.) Signed-off-by: Andreas Gruenbacher --- src/Makefile | 3 +- src/mmap-rw-fault.c | 169 ++++++++++++++++++++++++++++++++++++++++++ tests/generic/637 | 40 ++++++++++ tests/generic/637.out | 2 + tests/generic/group | 1 + 5 files changed, 214 insertions(+), 1 deletion(-) create mode 100644 src/mmap-rw-fault.c create mode 100755 tests/generic/637 create mode 100644 tests/generic/637.out diff --git a/src/Makefile b/src/Makefile index cc0b9579..13cdf19b 100644 --- a/src/Makefile +++ b/src/Makefile @@ -17,7 +17,8 @@ TARGETS = dirstress fill fill2 getpagesize holes lstat64 \ t_mmap_cow_race t_mmap_fallocate fsync-err t_mmap_write_ro \ t_ext4_dax_journal_corruption t_ext4_dax_inline_corruption \ t_ofd_locks t_mmap_collision mmap-write-concurrent \ - t_get_file_time t_create_short_dirs t_create_long_dirs t_enospc + t_get_file_time t_create_short_dirs t_create_long_dirs t_enospc \ + mmap-rw-fault LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ preallo_rw_pattern_writer ftrunc trunc fs_perms testx looptest \ diff --git a/src/mmap-rw-fault.c b/src/mmap-rw-fault.c new file mode 100644 index 00000000..31778769 --- /dev/null +++ b/src/mmap-rw-fault.c @@ -0,0 +1,169 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Trigger mmap page faults in the same file during pread and pwrite. + * Copyright (C) 2021 Red Hat, Inc. All Rights Reserved. + * Written by Andreas Gruenbacher + */ + +#ifndef _GNU_SOURCE +#define _GNU_SOURCE /* to get definition of O_DIRECT flag. */ +#endif + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +char *filename; +unsigned int page_size; +void *page; +char *addr; +int fd; +ssize_t ret; + +/* + * Leave a hole at the beginning of the test file and initialize a block of + * @page_size bytes at offset @page_size to @c. Then, reopen the file and + * mmap the first two pages. + */ +void init(char c, int flags) +{ + fd = open(filename, O_CREAT | O_TRUNC | O_WRONLY | O_DIRECT, 0666); + if (fd == -1) + goto fail; + memset(page, c, page_size); + ret = pwrite(fd, page, page_size, page_size); + if (ret != page_size) + goto fail; + if (close(fd)) + goto fail; + + fd = open(filename, flags); + if (fd == -1) + goto fail; + addr = mmap(NULL, 2 * page_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0); + if (addr == MAP_FAILED) + err(1, NULL); + return; + +fail: + err(1, "%s", filename); +} + +void done(void) +{ + if (fsync(fd)) + goto fail; + if (close(fd)) + goto fail; + return; + +fail: + err(1, "%s", filename); +} + +static ssize_t do_read(int fd, void *buf, size_t count, off_t offset) +{ + ssize_t count2 = 0, ret; + + do { + ret = pread(fd, buf, count, offset); + if (ret == -1) { + if (errno == EINTR) + continue; + break; + } + if (ret == 0) + break; + count2 += ret; + buf += ret; + count -= ret; + } while (count); + return count2; +} + +static ssize_t do_write(int fd, const void *buf, size_t count, off_t offset) +{ + ssize_t count2 = 0, ret; + + do { + ret = pwrite(fd, buf, count, offset); + if (ret == -1) { + if (errno == EINTR) + continue; + break; + } + if (ret == 0) + break; + count2 += ret; + buf += ret; + count -= ret; + } while (count); + return count2; +} + +int main(int argc, char *argv[]) +{ + if (argc != 2) + errx(1, "no test filename argument given"); + filename = argv[1]; + + page_size = ret = sysconf(_SC_PAGE_SIZE); + if (ret == -1) + err(1, NULL); + + ret = posix_memalign(&page, page_size, page_size); + if (ret) { + errno = ENOMEM; + err(1, NULL); + } + + /* + * Make sure page faults during pread are handled correctly. + */ + init('a', O_RDWR); + ret = do_read(fd, addr, page_size, page_size); + if (ret != page_size) + err(1, "pread %s: %ld != %u", filename, ret, page_size); + if (memcmp(addr, page, page_size)) + errx(1, "pread is broken"); + done(); + + init('b', O_RDWR | O_DIRECT); + ret = do_read(fd, addr, page_size, page_size); + if (ret != page_size) + err(1, "pread %s (O_DIRECT): %ld != %u", filename, ret, page_size); + if (memcmp(addr, page, page_size)) + errx(1, "pread (D_DIRECT) is broken"); + done(); + + /* + * Make sure page faults during pwrite are handled correctly. + */ + init('c', O_RDWR); + ret = do_write(fd, addr + page_size, page_size, 0); + if (ret != page_size) + err(1, "pwrite %s: %ld != %u", filename, ret, page_size); + if (memcmp(addr, page, page_size)) + errx(1, "pwrite is broken"); + done(); + + init('d', O_RDWR | O_DIRECT); + ret = do_write(fd, addr + page_size, page_size, 0); + if (ret != page_size) + err(1, "pwrite %s (O_DIRECT): %ld != %u", filename, ret, page_size); + if (memcmp(addr, page, page_size)) + errx(1, "pwrite (O_DIRECT) is broken"); + done(); + + if (unlink(filename)) + err(1, "unlink %s", filename); + + return 0; +} diff --git a/tests/generic/637 b/tests/generic/637 new file mode 100755 index 00000000..cbb3d119 --- /dev/null +++ b/tests/generic/637 @@ -0,0 +1,40 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2021 Red Hat, Inc. All Rights Reserved. +# +# FS QA Test 637 +# +# Trigger mmap page faults in the same file during pread and pwrite +# +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 $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here + +# Modify as appropriate. +_supported_fs generic +_require_test +_require_test_program mmap-rw-fault + +$here/src/mmap-rw-fault $TEST_DIR/mmap-rw-fault.tmp 2>&1 + +# success, all done +echo "Silence is golden" +status=0 +exit diff --git a/tests/generic/637.out b/tests/generic/637.out new file mode 100644 index 00000000..55a3d825 --- /dev/null +++ b/tests/generic/637.out @@ -0,0 +1,2 @@ +QA output created by 637 +Silence is golden diff --git a/tests/generic/group b/tests/generic/group index 105763c4..01996b48 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -639,3 +639,4 @@ 634 auto quick atime bigtime 635 auto quick atime bigtime shutdown 636 auto quick swap +637 auto -- 2.26.3