iotests: Test qemu-img convert --salvage

This test converts a simple image to another, but blkdebug injects
block_status and read faults at some offsets.  The resulting image
should be the same as the input image, except that sectors that could
not be read have to be 0.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190507203508.18026-7-mreitz@redhat.com
Tested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
[mreitz: Dropped superfluous printf from _filter_offsets, as suggested
         by Vladimir; disable test for VDI and IMGOPTSSYNTAX]
Signed-off-by: Max Reitz <mreitz@redhat.com>

1 files changed, 170 insertions, 0 deletions

diff --git a/tests/qemu-iotests/251 b/tests/qemu-iotests/251
new file mode 100755
index 0000000000..13f85de9cd
--- /dev/null
+++ b/tests/qemu-iotests/251
@@ -0,0 +1,170 @@
+#!/usr/bin/env bash
+#
+# Test qemu-img convert --salvage
+#
+# 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/>.
+#
+
+# creator
+owner=mreitz@redhat.com
+
+seq=$(basename $0)
+echo "QA output created by $seq"
+
+status=1	# failure is the default!
+
+_cleanup()
+{
+    _cleanup_test_img
+}
+trap "_cleanup; exit \$status" 0 1 2 3 15
+
+# get standard environment, filters and checks
+. ./common.rc
+. ./common.filter
+. ./common.qemu
+
+_supported_fmt generic
+_supported_proto file
+_supported_os Linux
+
+if [ "$IMGOPTSSYNTAX" = "true" ]; then
+    # We use json:{} filenames here, so we cannot work with additional options.
+    _unsupported_fmt $IMGFMT
+else
+    # With VDI, the output is ordered differently.  Just disable it.
+    _unsupported_fmt vdi
+fi
+
+
+TEST_IMG="$TEST_IMG.orig" _make_test_img 64M
+
+$QEMU_IO -c 'write -P 42 0 64M' "$TEST_IMG.orig" | _filter_qemu_io
+
+
+sector_size=512
+
+# Offsets on which to fail block-status.  Keep in ascending order so
+# the indexing done by _filter_offsets will appear in ascending order
+# in the output as well.
+status_fail_offsets="$((16 * 1024 * 1024 + 8192))
+                     $((33 * 1024 * 1024 + 512))"
+
+# Offsets on which to fail reads.  Keep in ascending order for the
+# same reason.
+# The second element is shared with $status_fail_offsets on purpose.
+# Starting with the third element, we test what happens when a
+# continuous range of sectors is inaccessible.
+read_fail_offsets="$((32 * 1024 * 1024 - 65536))
+                   $((33 * 1024 * 1024 + 512))
+                   $(seq $((34 * 1024 * 1024)) $sector_size \
+                         $((34 * 1024 * 1024 + 4096 - $sector_size)))"
+
+
+# blkdebug must be above the format layer so it can intercept all
+# block-status events
+source_img="json:{'driver': 'blkdebug',
+                  'image': {
+                      'driver': '$IMGFMT',
+                      'file': {
+                          'driver': 'file',
+                          'filename': '$TEST_IMG.orig'
+                      }
+                  },
+                  'inject-error': ["
+
+for ofs in $status_fail_offsets
+do
+    source_img+="{ 'event': 'none',
+                   'iotype': 'block-status',
+                   'errno': 5,
+                   'sector': $((ofs / sector_size)) },"
+done
+
+for ofs in $read_fail_offsets
+do
+    source_img+="{ 'event': 'none',
+                   'iotype': 'read',
+                   'errno': 5,
+                   'sector': $((ofs / sector_size)) },"
+done
+
+# Remove the trailing comma and terminate @inject-error and json:{}
+source_img="${source_img%,} ] }"
+
+
+echo
+
+
+_filter_offsets() {
+    filters=
+
+    index=0
+    for ofs in $1
+    do
+        filters+=" -e s/$ofs/status_fail_offset_$index/"
+        index=$((index + 1))
+    done
+
+    index=0
+    for ofs in $2
+    do
+        filters+=" -e s/$ofs/read_fail_offset_$index/"
+        index=$((index + 1))
+    done
+
+    sed $filters
+}
+
+# While determining the number of allocated sectors in the input
+# image, we should see one block status warning per element of
+# $status_fail_offsets.
+#
+# Then, the image is read.  Since the block status is queried in
+# basically the same way, the same warnings as in the previous step
+# should reappear.  Interleaved with those we should see a read
+# warning per element of $read_fail_offsets.
+# Note that $read_fail_offsets and $status_fail_offsets share an
+# element (read_fail_offset_1 == status_fail_offset_1), so
+# "status_fail_offset_1" in the output is the same as
+# "read_fail_offset_1".
+$QEMU_IMG convert --salvage "$source_img" "$TEST_IMG" 2>&1 \
+    | _filter_offsets "$status_fail_offsets" "$read_fail_offsets"
+
+echo
+
+# The offsets where the block status could not be determined should
+# have been treated as containing data and thus should be correct in
+# the output image.
+# The offsets where reading failed altogether should be 0.  Make them
+# 0 in the input image, too, so we can compare both images.
+for ofs in $read_fail_offsets
+do
+    $QEMU_IO -c "write -z $ofs $sector_size" "$TEST_IMG.orig" \
+        | _filter_qemu_io \
+        | _filter_offsets '' "$read_fail_offsets"
+done
+
+echo
+
+# These should be equal now.
+$QEMU_IMG compare "$TEST_IMG.orig" "$TEST_IMG"
+
+
+# success, all done
+echo "*** done"
+rm -f $seq.full
+status=0