iotests/244: Add test cases for keep_data_file

Add various test cases around keep_data_file to the existing data_file
test suite 244.

Signed-off-by: Hanna Czenczek <hreitz@redhat.com>
Message-ID: <20250530084448.192369-5-hreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
[kwolf: Added prealloc=full to the test]
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

tests/qemu-iotests/244

@@ -384,6 +384,77 @@ $QEMU_IMG compare --image-opts \
     "driver=raw,file.filename=$TEST_IMG.data"  \
     "file.filename=$TEST_IMG,backing.file.filename=$TEST_IMG.base"
 
+echo
+echo '=== keep_data_file tests ==='
+
+echo
+echo '--- Creating test data file ---'
+
+# Easiest way to create the raw data file without having to create and
+# access it manually
+_make_test_img -o "data_file=$TEST_IMG.data,data_file_raw=on" 1M
+# Values chosen by a fair random.org evaluation
+$QEMU_IO -c 'write -P 3 0 512k' -c 'write -P 96 512k 512k' "$TEST_IMG" |
+    _filter_qemu_io
+
+echo
+echo '--- Testing stand-alone option ---'
+
+# Cannot work, needs data file
+_make_test_img -o "keep_data_file=on" 1M
+
+# Invalid option value
+_make_test_img -o "keep_data_file=true" 1M
+
+# Should be the same as omitting
+_make_test_img -o "keep_data_file=off" 1M
+
+# No preallocation is OK when also specifying data_file_raw; otherwise, none of
+# the data file will be mapped, i.e. its contents will stay hidden, so
+# requesting its contents to be kept (but hidden) doesn't make much sense.
+#
+# Metadata preallocation is OK: It will not overwrite the data file's contents,
+# but ensure the contents are mapped and visible.
+#
+# Any data preallocation (like falloc) is not OK, as this would overwrite the
+# data file's contents despite keep_data_file requesting they should not be
+# overwritten.
+#
+# Note that all of these cases use the data file created above: This verifies
+# that when passing keep_data_file=on, the data file is always kept as-is (and
+# e.g. not deleted on error).
+for prealloc in off metadata falloc full; do
+    # Without metadata preallocation, the data_file_raw flag is required so that
+    # the data file's contents are visible.
+    for data_file_raw in off on; do
+        echo
+        echo "--- Testing prealloc=$prealloc data_file_raw=$data_file_raw ---"
+
+        # Remove previously existing qcow2 (metadata) file
+        _cleanup_test_img
+
+        opts="data_file=$TEST_IMG.data,keep_data_file=on"
+        opts+=",preallocation=$prealloc"
+        opts+=",data_file_raw=$data_file_raw"
+
+        _make_test_img -o "$opts" 1M
+        if [ -f "$TEST_IMG" ]; then
+            $QEMU_IO -c 'read -P 3 0 512k' -c 'read -P 96 512k 512k' "$TEST_IMG" |
+                _filter_qemu_io
+        fi
+    done
+done
+
+echo
+echo '--- Testing non-existent data file ---'
+
+# Maybe a matter of taste whether this should fail or create the file, but
+# failing is simpler (= will always skip create) and seems safer (users may
+# expect the file to exist, and the error will warn them when it does not).
+_make_test_img \
+    -o "data_file=$TEST_IMG.doesnotexist,keep_data_file=on,data_file_raw=on" \
+    1M
+
 # success, all done
 echo "*** done"
 rm -f $seq.full

tests/qemu-iotests/244.out

@@ -197,4 +197,65 @@ wrote 1048576/1048576 bytes at offset 0
 
 Comparing qcow2 image and raw data file:
 Images are identical.
+
+=== keep_data_file tests ===
+
+--- Creating test data file ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on
+wrote 524288/524288 bytes at offset 0
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+wrote 524288/524288 bytes at offset 524288
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+--- Testing stand-alone option ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 keep_data_file=on
+qemu-img: TEST_DIR/t.IMGFMT: Must not use 'keep_data_file=on' without 'data_file'
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 keep_data_file=true
+qemu-img: TEST_DIR/t.IMGFMT: Invalid value 'true' for 'keep_data_file': Must be 'on' or 'off'
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 keep_data_file=off
+
+--- Testing prealloc=off data_file_raw=off ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=off keep_data_file=on preallocation=off
+qemu-img: TEST_DIR/t.IMGFMT: 'keep_data_file=on' requires 'preallocation=metadata' or 'data_file_raw=on', or the file contents will not be visible
+
+--- Testing prealloc=off data_file_raw=on ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on keep_data_file=on preallocation=off
+read 524288/524288 bytes at offset 0
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 524288/524288 bytes at offset 524288
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+--- Testing prealloc=metadata data_file_raw=off ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=off keep_data_file=on preallocation=metadata
+read 524288/524288 bytes at offset 0
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 524288/524288 bytes at offset 524288
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+--- Testing prealloc=metadata data_file_raw=on ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on keep_data_file=on preallocation=metadata
+read 524288/524288 bytes at offset 0
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+read 524288/524288 bytes at offset 524288
+512 KiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
+
+--- Testing prealloc=falloc data_file_raw=off ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=off keep_data_file=on preallocation=falloc
+qemu-img: TEST_DIR/t.IMGFMT: Preallocating more than only metadata would overwrite the external data file's content and is therefore incompatible with 'keep_data_file=on'
+
+--- Testing prealloc=falloc data_file_raw=on ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on keep_data_file=on preallocation=falloc
+qemu-img: TEST_DIR/t.IMGFMT: Preallocating more than only metadata would overwrite the external data file's content and is therefore incompatible with 'keep_data_file=on'
+
+--- Testing prealloc=full data_file_raw=off ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=off keep_data_file=on preallocation=full
+qemu-img: TEST_DIR/t.IMGFMT: Preallocating more than only metadata would overwrite the external data file's content and is therefore incompatible with 'keep_data_file=on'
+
+--- Testing prealloc=full data_file_raw=on ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.data data_file_raw=on keep_data_file=on preallocation=full
+qemu-img: TEST_DIR/t.IMGFMT: Preallocating more than only metadata would overwrite the external data file's content and is therefore incompatible with 'keep_data_file=on'
+
+--- Testing non-existent data file ---
+Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=1048576 data_file=TEST_DIR/t.IMGFMT.doesnotexist data_file_raw=on keep_data_file=on
+qemu-img: TEST_DIR/t.IMGFMT: Could not open 'TEST_DIR/t.IMGFMT.doesnotexist': No such file or directory
 *** done