iotests: vmdk: Enable zeroed_grained=on by default

In order to avoid bitrot in the zero cluster code in VMDK, enable
zeroed_grain=on by default for the tests.

059 now unsets the default options because zeroed_grain=on works only
with some subformats and the test case tests many different subformats,
including those for which it doesn't work.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20200430133007.170335-7-kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

tests/qemu-iotests/059

@@ -41,9 +41,9 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt vmdk
 _supported_proto file
 _supported_os Linux
-_unsupported_imgopts "subformat=monolithicFlat" \
-                     "subformat=twoGbMaxExtentFlat" \
-                     "subformat=twoGbMaxExtentSparse"
+
+# We test all kinds of VMDK options here, so ignore user-specified options
+IMGOPTS=""
 
 capacity_offset=16
 granularity_offset=20

tests/qemu-iotests/check

@@ -546,6 +546,9 @@ fi
 if [ "$IMGFMT" == "luks" ] && ! (echo "$IMGOPTS" | grep "iter-time=" > /dev/null); then
     IMGOPTS=$(_optstr_add "$IMGOPTS" "iter-time=10")
 fi
+if [ "$IMGFMT" == "vmdk" ] && ! (echo "$IMGOPTS" | grep "zeroed_grain=" > /dev/null); then
+    IMGOPTS=$(_optstr_add "$IMGOPTS" "zeroed_grain=on")
+fi
 
 if [ -z "$SAMPLE_IMG_DIR" ]; then
         SAMPLE_IMG_DIR="$source_iotests/sample_images"