[Libguestfs] [nbdkit PATCH 4/4] RFC tests: Add test to cover unusual .can_flush return
Richard W.M. Jones
rjones at redhat.com
Tue Mar 17 08:19:07 UTC 2020
On Mon, Mar 16, 2020 at 10:36:17PM -0500, Eric Blake wrote:
> We want some testsuite coverage of handling non-1 .can_flush values.
> The only in-tree plugin with this property is nbd-standalone, but it
> doesn't get frequently tested, not to mention that the next patch will
> change it to work with older nbdkit.
>
> Signed-off-by: Eric Blake <eblake at redhat.com>
> ---
>
> work in progress: currently compiles but fails during test; posting it
> now to show my thoughts before I go to bed
Yes, it all looks reasonable so far.
Rich.
> tests/Makefile.am | 21 +++++++
> tests/test-flush.sh | 85 +++++++++++++++++++++++++++
> tests/test-flush-plugin.c | 119 ++++++++++++++++++++++++++++++++++++++
> 3 files changed, 225 insertions(+)
> create mode 100755 tests/test-flush.sh
> create mode 100644 tests/test-flush-plugin.c
>
> diff --git a/tests/Makefile.am b/tests/Makefile.am
> index 65dd148d..7e0024d3 100644
> --- a/tests/Makefile.am
> +++ b/tests/Makefile.am
> @@ -116,6 +116,7 @@ EXTRA_DIST = \
> test-extentlist.sh \
> test-file-extents.sh \
> test-floppy.sh \
> + test-flush.sh \
> test-foreground.sh \
> test-fua.sh \
> test-full.sh \
> @@ -267,6 +268,7 @@ TESTS += \
> test-foreground.sh \
> test-debug-flags.sh \
> test-long-name.sh \
> + test-flush.sh \
> test-swap.sh \
> test-shutdown.sh \
> $(NULL)
> @@ -282,6 +284,25 @@ test_socket_activation_CPPFLAGS = \
> $(NULL)
> test_socket_activation_CFLAGS = $(WARNINGS_CFLAGS)
>
> +# check_LTLIBRARIES won't build a shared library (see automake manual).
> +# So we have to do this and add a dependency.
> +noinst_LTLIBRARIES += \
> + test-flush-plugin.la \
> + $(NULL)
> +test-flush.sh: test-flush-plugin.la
> +
> +test_flush_plugin_la_SOURCES = \
> + test-flush-plugin.c \
> + $(top_srcdir)/include/nbdkit-plugin.h \
> + $(NULL)
> +test_flush_plugin_la_CPPFLAGS = -I$(top_srcdir)/include
> +test_flush_plugin_la_CFLAGS = $(WARNINGS_CFLAGS)
> +# For use of the -rpath option, see:
> +# https://lists.gnu.org/archive/html/libtool/2007-07/msg00067.html
> +test_flush_plugin_la_LDFLAGS = \
> + -module -avoid-version -shared -rpath /nowhere \
> + $(NULL)
> +
> # check_LTLIBRARIES won't build a shared library (see automake manual).
> # So we have to do this and add a dependency.
> noinst_LTLIBRARIES += \
> diff --git a/tests/test-flush.sh b/tests/test-flush.sh
> new file mode 100755
> index 00000000..54801b3a
> --- /dev/null
> +++ b/tests/test-flush.sh
> @@ -0,0 +1,85 @@
> +#!/usr/bin/env bash
> +# nbdkit
> +# Copyright (C) 2019-2020 Red Hat Inc.
> +#
> +# Redistribution and use in source and binary forms, with or without
> +# modification, are permitted provided that the following conditions are
> +# met:
> +#
> +# * Redistributions of source code must retain the above copyright
> +# notice, this list of conditions and the following disclaimer.
> +#
> +# * Redistributions in binary form must reproduce the above copyright
> +# notice, this list of conditions and the following disclaimer in the
> +# documentation and/or other materials provided with the distribution.
> +#
> +# * Neither the name of Red Hat nor the names of its contributors may be
> +# used to endorse or promote products derived from this software without
> +# specific prior written permission.
> +#
> +# THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
> +# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
> +# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
> +# PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
> +# CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
> +# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
> +# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> +# USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
> +# ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
> +# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
> +# OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
> +# SUCH DAMAGE.
> +
> +source ./functions.sh
> +set -x
> +
> +requires nbdsh --version
> +
> +plugin=.libs/test-flush-plugin.so
> +requires test -f $plugin
> +
> +# Test what happens when a plugin fails .can_flush
> +nbdsh -c '
> +try:
> + h.connect_command (["nbdkit", "-s", "-v", "'$plugin'", "level=-1"])
> +except nbd.Error as ex:
> + exit (0)
> +# If we got here, things are broken
> +exit (1)
> +'
> +
> +# A read-only connection never triggers .can_flush
> +nbdsh -c '
> +h.connect_command (["nbdkit", "-s", "-r", "-v", "'$plugin'", "level=-1"])
> +assert h.is_read_only () == 1
> +assert h.can_flush () == 0
> +assert h.can_fua () == 0
> +'
> +
> +# Disable flush and FUA
> +nbdsh -c '
> +h.connect_command (["nbdkit", "-s", "-v", "'$plugin'", "0"])
> +assert h.is_read_only () == 0
> +assert h.can_flush () == 0
> +assert h.can_fua () == 0
> +'
> +
> +# Normal flush, emulated FUA
> +nbdsh -c '
> +h.connect_command (["nbdkit", "-s", "-v", "'$plugin'", "1"])
> +assert h.is_read_only () == 0
> +assert h.can_flush () == 1
> +assert h.can_fua () == 1
> +# try direct flush; check that output has "handling flush"
> +# try write with FUA; check that output has "handling flush"
> +'
> +
> +# Unusual return value for .can_flush, native FUA
> +nbdsh -c '
> +h.connect_command (["nbdkit", "-s", "-v", "'$plugin'", "2"])
> +assert h.is_read_only () == 0
> +assert h.can_flush () == 1
> +assert h.can_fua () == 1
> +# try direct flush; check that output has "handling flush"
> +# try write with FUA; check that output has "handling native FUA"
> +'
> diff --git a/tests/test-flush-plugin.c b/tests/test-flush-plugin.c
> new file mode 100644
> index 00000000..5553c607
> --- /dev/null
> +++ b/tests/test-flush-plugin.c
> @@ -0,0 +1,119 @@
> +/* nbdkit
> + * Copyright (C) 2013-2020 Red Hat Inc.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions are
> + * met:
> + *
> + * * Redistributions of source code must retain the above copyright
> + * notice, this list of conditions and the following disclaimer.
> + *
> + * * Redistributions in binary form must reproduce the above copyright
> + * notice, this list of conditions and the following disclaimer in the
> + * documentation and/or other materials provided with the distribution.
> + *
> + * * Neither the name of Red Hat nor the names of its contributors may be
> + * used to endorse or promote products derived from this software without
> + * specific prior written permission.
> + *
> + * THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND
> + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
> + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
> + * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR
> + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
> + * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
> + * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
> + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
> + * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
> + * SUCH DAMAGE.
> + */
> +
> +#include <config.h>
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +
> +#define NBDKIT_API_VERSION 2
> +
> +#include <nbdkit-plugin.h>
> +
> +/* level abuses our knowledge of internal nbdkit values:
> + * -1: force error during connect
> + * 0: no flush, no FUA
> + * 1: flush works, FUA is emulated
> + * 2: flush works, FUA is native
> + */
> +static int level;
> +
> +static int
> +flush_config (const char *key, const char *value)
> +{
> + if (strcmp (key, "level") == 0)
> + return nbdkit_parse_int (key, value, &level);
> + nbdkit_error ("unknown parameter '%s'", key);
> + return -1;
> +}
> +
> +/* Implements both .can_flush and .can_fua */
> +static int
> +flush_level (void *handle)
> +{
> + return level;
> +}
> +
> +static void *
> +flush_open (int readonly)
> +{
> + return NBDKIT_HANDLE_NOT_NEEDED;
> +}
> +
> +static int64_t
> +flush_get_size (void *handle)
> +{
> + return 1024*1024;
> +}
> +
> +#define THREAD_MODEL NBDKIT_THREAD_MODEL_PARALLEL
> +
> +static int
> +flush_pread (void *handle, void *buf, uint32_t count, uint64_t offset,
> + uint32_t flags)
> +{
> + memset (buf, 0, count);
> + return 0;
> +}
> +
> +static int
> +flush_pwrite (void *handle, const void *buf, uint32_t count, uint64_t offset,
> + uint32_t flags)
> +{
> + if (flags & NBDKIT_FLAG_FUA)
> + nbdkit_debug ("handling native FUA");
> + return 0;
> +}
> +
> +static int
> +flush_flush (void *handle, uint32_t flags)
> +{
> + nbdkit_debug ("handling flush");
> + return 0;
> +}
> +
> +static struct nbdkit_plugin plugin = {
> + .name = "flush",
> + .version = PACKAGE_VERSION,
> + .config = flush_config,
> + .magic_config_key = "level",
> + .open = flush_open,
> + .get_size = flush_get_size,
> + .pread = flush_pread,
> + .pwrite = flush_pwrite,
> + .can_flush = flush_level,
> + .can_fua = flush_level,
> + .flush = flush_flush,
> +};
> +
> +NBDKIT_REGISTER_PLUGIN(plugin)
> --
> 2.25.1
>
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