iotests: Test unaligned raw images with O_DIRECT

We already have 221 for accesses through the page cache, but it is
better to create a new file for O_DIRECT instead of integrating those
test cases into 221.  This way, we can make use of
_supported_cache_modes (and _default_cache_mode) so the test is
automatically skipped on filesystems that do not support O_DIRECT.

As part of the split, add _supported_cache_modes to 221.  With that, it
no longer fails when run with -c none or -c directsync.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 84 insertions, 0 deletions

diff --git a/tests/qemu-iotests/253 b/tests/qemu-iotests/253
new file mode 100755
index 0000000000..d88d5afa45
--- /dev/null
+++ b/tests/qemu-iotests/253
@@ -0,0 +1,84 @@
+#!/usr/bin/env bash
+#
+# Test qemu-img vs. unaligned images; O_DIRECT version
+# (Originates from 221)
+#
+# Copyright (C) 2019 Red Hat, Inc.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+seq="$(basename $0)"
+echo "QA output created by $seq"
+
+status=1 # failure is the default!
+
+_cleanup()
+{
+    _cleanup_test_img
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+
+_supported_fmt raw
+_supported_proto file
+_supported_os Linux
+
+_default_cache_mode none
+_supported_cache_modes none directsync
+
+echo
+echo "=== Check mapping of unaligned raw image ==="
+echo
+
+# We do not know how large a physical sector is, but it is certainly
+# going to be a factor of 1 MB
+size=$((1 * 1024 * 1024 - 1))
+
+# qemu-img create rounds size up to BDRV_SECTOR_SIZE
+_make_test_img $size
+$QEMU_IMG map --output=json --image-opts \
+    "driver=$IMGFMT,file.driver=file,file.filename=$TEST_IMG,cache.direct=on" \
+    | _filter_qemu_img_map
+
+# so we resize it and check again
+truncate --size=$size "$TEST_IMG"
+$QEMU_IMG map --output=json --image-opts \
+    "driver=$IMGFMT,file.driver=file,file.filename=$TEST_IMG,cache.direct=on" \
+    | _filter_qemu_img_map
+
+# qemu-io with O_DIRECT always writes whole physical sectors.  Again,
+# we do not know how large a physical sector is, so we just start
+# writing from a 64 kB boundary, which should always be aligned.
+offset=$((1 * 1024 * 1024 - 64 * 1024))
+$QEMU_IO -c "w $offset $((size - offset))" "$TEST_IMG" | _filter_qemu_io
+$QEMU_IMG map --output=json --image-opts \
+    "driver=$IMGFMT,file.driver=file,file.filename=$TEST_IMG,cache.direct=on" \
+    | _filter_qemu_img_map
+
+# Resize it and check again -- contrary to 221, we may not get partial
+# sectors here, so there should be only two areas (one zero, one
+# data).
+truncate --size=$size "$TEST_IMG"
+$QEMU_IMG map --output=json --image-opts \
+    "driver=$IMGFMT,file.driver=file,file.filename=$TEST_IMG,cache.direct=on" \
+    | _filter_qemu_img_map
+
+# success, all done
+echo '*** done'
+rm -f $seq.full
+status=0