From patchwork Wed Mar 20 14:36:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josef Bacik X-Patchwork-Id: 13597916 Received: from mail-oi1-f179.google.com (mail-oi1-f179.google.com [209.85.167.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 573DB482DB for ; Wed, 20 Mar 2024 14:36:48 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.167.179 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710945410; cv=none; b=pdG1hz12QSVTqtts50LfP8TFU/Wcau5dohApaAXC5+AEdWGSnWS6Ms6RW5vmDDBBmmtzsF/fcu36B7el9cdBGQm2s5TCv0pHHbQ/dCrLOfH6E2ABr9Vc0QEaPP+ucsU+b4jp228/7jvD2AEQ2fCwOJWR83UoB/5KIZOxpvrCgKU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1710945410; c=relaxed/simple; bh=0dzmvSNXDEjI7bO13sJavVyxPJ+BMK8j7eQSjbkgiC0=; h=From:To:Subject:Date:Message-ID:MIME-Version; b=Y1588NFBsIxkYPjE+4cCKjn0mOYIVeEIGqQH7FSaVpbrrHTXfozxpg+LPA40xS4oiXRnMUeCibJF3RB1c9pPNwXNkU99wyX7k+ScvGi/mKFteV0/8Ec9FY14e2hrmE3vGF+2hLvcR2Ir2/NjMOVCE7I/W06T4a2IEYr87dVYAs4= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=toxicpanda.com; spf=none smtp.mailfrom=toxicpanda.com; dkim=pass (2048-bit key) header.d=toxicpanda-com.20230601.gappssmtp.com header.i=@toxicpanda-com.20230601.gappssmtp.com header.b=Gq7ZDr+S; arc=none smtp.client-ip=209.85.167.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=toxicpanda.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=toxicpanda.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=toxicpanda-com.20230601.gappssmtp.com header.i=@toxicpanda-com.20230601.gappssmtp.com header.b="Gq7ZDr+S" Received: by mail-oi1-f179.google.com with SMTP id 5614622812f47-3c3a4101721so317912b6e.1 for ; Wed, 20 Mar 2024 07:36:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toxicpanda-com.20230601.gappssmtp.com; s=20230601; t=1710945407; x=1711550207; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:from:to:cc:subject:date:message-id:reply-to; bh=3KWocK4KNuC3im4RVRinIZdPR5x/tqHwwO2pPUGXNV8=; b=Gq7ZDr+Sgk3Nz0zGyWPcogQzxWGeZPZo7XBeEqiHLwOArCzjsKtFA9zaNfq6Cf74fz +QhRb2NEHHYfLK1L1VpRRRccT3XdqhSBjP8pe3IobUz4SCXMYAQk/Znb2Kdm4E/tvxuN WH5Tr85WCMBw+WS/DWQXHyQTwdybsXCMD3lZnCbGwtkQgeyskUCK0BnFNLbMwYWAXC05 BQ1WaHL6er/f8e6vPZ8eHymlpab5Pj2MokbE0b44X8VX4v+80hJ6PIqIAkanM2TiYqZS P1LUTCXXZkPUZLcM1X2ppeXiu85gV8kUhKysOBOYs+sf+wipGFZhRlHjOCquGdk8RKMz Fs3w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1710945407; x=1711550207; h=content-transfer-encoding:mime-version:message-id:date:subject:to :from:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=3KWocK4KNuC3im4RVRinIZdPR5x/tqHwwO2pPUGXNV8=; b=OGUdRkvhpxxv0xQ9ombvfIcPXC+rytpjenifwnf6rve1K8px9fiVRKmbXKJYV70xsT U5ALWf70QajhKgtRbSdLzA4Qb4Wo2XpfK1iEO4hvV6IgpBF30guo1ujF2IwiwCo6rMDV Cpg7n839TiPhV5mTgz9r2Wh5d6t2DmRtcI9uLzfYJQpJWxE9nLygLKZIrqlBBf+wxiGL +VgjCMsOJ3QPo7Zs8WnxwlHw2ff6bHQCkYp/SmYJsGVAhChMtG6My7L0omfpd+vz5ypQ XhbdywPfkg/psBpjVAp6FkbwoViVwQcHNPXon7mlTbek7YDaxh23xu1AIoNzoBNsbXXP 2/pg== X-Forwarded-Encrypted: i=1; AJvYcCUvargYnL49Byd0RmlYGMx+sgNvR/v7cPhqiHZTTAND9f0aFnfTFhpGJR13jAyYRYUVuEMMqABD9HO4boaEJ/+cteAJxHvq8vMeJNI= X-Gm-Message-State: AOJu0Yw6pk+5e7CVPL7KFH6CQRRYgjrthTbzk4K6GrTUJtTXJV5RluTJ cbELNg1WnPshbvbI8yLXj5KIlqGOt/Mvigl04RYlvvjjv2tIlbqILyUC6GJhNE8= X-Google-Smtp-Source: AGHT+IFgxi7O2L2yBwP9rAFdXFOi0JAX/OnP3OsP0BbowtXmdKHTeeTAUJMZZOtQBxscFY29LXcOcQ== X-Received: by 2002:a05:6808:140f:b0:3c2:60cb:5bb4 with SMTP id w15-20020a056808140f00b003c260cb5bb4mr6866176oiv.6.1710945407333; Wed, 20 Mar 2024 07:36:47 -0700 (PDT) Received: from localhost (076-182-020-124.res.spectrum.com. [76.182.20.124]) by smtp.gmail.com with ESMTPSA id bq23-20020a05622a1c1700b00430d1c9bfebsm3805409qtb.43.2024.03.20.07.36.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Mar 2024 07:36:46 -0700 (PDT) From: Josef Bacik To: fstests@vger.kernel.org, linux-btrfs@vger.kernel.org, kernel-team@fb.com Subject: [PATCH v3] generic/808: add a regression test for fiemap into an mmap range Date: Wed, 20 Mar 2024 10:36:42 -0400 Message-ID: <076b7d22d653a046bf3710c4fa04cc155b6cf07b.1710945314.git.josef@toxicpanda.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Btrfs had a deadlock that you could trigger by mmap'ing a large file and using that as the buffer for fiemap. This test adds a c program to do this, and the fstest creates a large enough file and then runs the reproducer on the file. Without the fix btrfs deadlocks, with the fix we pass fine. Signed-off-by: Josef Bacik Reviewed-by: Filipe Manana Reviewed-by: Anand Jain --- v2->v3: - Add fiemap-fault to .gitignore - Added a _cleanup() helper - Just let the output of fiemap-fault go instead of using || _fail - Added the munmap - Moved $dst to $TEST_DIR/$seq .gitignore | 1 + src/Makefile | 2 +- src/fiemap-fault.c | 74 +++++++++++++++++++++++++++++++++++++++++++ tests/generic/808 | 48 ++++++++++++++++++++++++++++ tests/generic/808.out | 2 ++ 5 files changed, 126 insertions(+), 1 deletion(-) create mode 100644 src/fiemap-fault.c create mode 100755 tests/generic/808 create mode 100644 tests/generic/808.out diff --git a/.gitignore b/.gitignore index 3b160209..f0fb72bd 100644 --- a/.gitignore +++ b/.gitignore @@ -205,6 +205,7 @@ tags /src/vfs/mount-idmapped /src/log-writes/replay-log /src/perf/*.pyc +/src/filemap-fault # Symlinked files /tests/generic/035.out diff --git a/src/Makefile b/src/Makefile index e7442487..ab98a06f 100644 --- a/src/Makefile +++ b/src/Makefile @@ -34,7 +34,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ attr_replace_test swapon mkswap t_attr_corruption t_open_tmpfiles \ fscrypt-crypt-util bulkstat_null_ocount splice-test chprojid_fail \ detached_mounts_propagation ext4_resize t_readdir_3 splice2pipe \ - uuid_ioctl t_snapshot_deleted_subvolume + uuid_ioctl t_snapshot_deleted_subvolume fiemap-fault EXTRA_EXECS = dmerror fill2attr fill2fs fill2fs_check scaleread.sh \ btrfs_crc32c_forged_name.py popdir.pl popattr.py \ diff --git a/src/fiemap-fault.c b/src/fiemap-fault.c new file mode 100644 index 00000000..73260068 --- /dev/null +++ b/src/fiemap-fault.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2024 Meta Platforms, Inc. All Rights Reserved. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +int prep_mmap_buffer(int fd, void **addr) +{ + struct stat st; + int ret; + + ret = fstat(fd, &st); + if (ret) + err(1, "failed to stat %d", fd); + + *addr = mmap(NULL, st.st_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); + if (*addr == MAP_FAILED) + err(1, "failed to mmap %d", fd); + + return st.st_size; +} + +int main(int argc, char *argv[]) +{ + struct fiemap *fiemap; + size_t sz, last = 0; + void *buf = NULL; + int ret, fd; + + if (argc != 2) + errx(1, "no in and out file name arguments given"); + + fd = open(argv[1], O_RDWR, 0666); + if (fd == -1) + err(1, "failed to open %s", argv[1]); + + sz = prep_mmap_buffer(fd, &buf); + + fiemap = (struct fiemap *)buf; + fiemap->fm_flags = 0; + fiemap->fm_extent_count = (sz - sizeof(struct fiemap)) / + sizeof(struct fiemap_extent); + + while (last < sz) { + int i; + + fiemap->fm_start = last; + fiemap->fm_length = sz - last; + + ret = ioctl(fd, FS_IOC_FIEMAP, (unsigned long)fiemap); + if (ret < 0) + err(1, "fiemap failed %d", errno); + for (i = 0; i < fiemap->fm_mapped_extents; i++) + last = fiemap->fm_extents[i].fe_logical + + fiemap->fm_extents[i].fe_length; + } + + munmap(buf, sz); + close(fd); + return 0; +} diff --git a/tests/generic/808 b/tests/generic/808 new file mode 100755 index 00000000..36015f35 --- /dev/null +++ b/tests/generic/808 @@ -0,0 +1,48 @@ +#! /bin/bash +# SPDX-License-Identifier: GPL-2.0 +# Copyright (c) 2024 Meta Platforms, Inc. All Rights Reserved. +# +# FS QA Test 808 +# +# Test fiemap into an mmaped buffer of the same file +# +# Create a reasonably large file, then run a program which mmaps it and uses +# that as a buffer for an fiemap call. This is a regression test for btrfs +# where we used to hold a lock for the duration of the fiemap call which would +# result in a deadlock if we page faulted. +# +. ./common/preamble +_begin_fstest quick auto fiemap +[ $FSTYP == "btrfs" ] && \ + _fixed_by_kernel_commit b0ad381fa769 \ + "btrfs: fix deadlock with fiemap and extent locking" + +_cleanup() +{ + rm -f $dst + cd / + rm -r -f $tmp.* +} + +# real QA test starts here +_supported_fs generic +_require_test +_require_odirect +_require_test_program fiemap-fault +dst=$TEST_DIR/$seq/fiemap-fault + +mkdir -p $TEST_DIR/$seq + +echo "Silence is golden" + +for i in $(seq 0 2 1000) +do + $XFS_IO_PROG -d -f -c "pwrite -q $((i * 4096)) 4096" $dst +done + +$here/src/fiemap-fault $dst + +# success, all done +status=$? +exit + diff --git a/tests/generic/808.out b/tests/generic/808.out new file mode 100644 index 00000000..88253428 --- /dev/null +++ b/tests/generic/808.out @@ -0,0 +1,2 @@ +QA output created by 808 +Silence is golden