xref: /qemu/tests/qemu-iotests/302 (revision b2a3cbb8) 
1#!/usr/bin/env python3
2# group: quick
3#
4# Tests converting qcow2 compressed to NBD
5#
6# Copyright (c) 2020 Nir Soffer <nirsof@gmail.com>
7#
8# This program is free software; you can redistribute it and/or modify
9# it under the terms of the GNU General Public License as published by
10# the Free Software Foundation; either version 2 of the License, or
11# (at your option) any later version.
12#
13# This program is distributed in the hope that it will be useful,
14# but WITHOUT ANY WARRANTY; without even the implied warranty of
15# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16# GNU General Public License for more details.
17#
18# You should have received a copy of the GNU General Public License
19# along with this program.  If not, see <http://www.gnu.org/licenses/>.
20#
21# owner=nirsof@gmail.com
22
23import io
24import tarfile
25
26import iotests
27
28from iotests import (
29    file_path,
30    qemu_img,
31    qemu_img_check,
32    qemu_img_create,
33    qemu_img_log,
34    qemu_img_measure,
35    qemu_io,
36    qemu_nbd_popen,
37    img_info_log,
38)
39
40iotests.script_initialize(supported_fmts=["qcow2"])
41
42# Create source disk. Using qcow2 to enable strict comparing later, and
43# avoid issues with random filesystem on CI environment.
44src_disk = file_path("disk.qcow2")
45qemu_img_create("-f", iotests.imgfmt, src_disk, "1g")
46qemu_io("-f", iotests.imgfmt, "-c", "write 1m 64k", src_disk)
47
48# The use case is writing qcow2 image directly into an ova file, which
49# is a tar file with specific layout. This is tricky since we don't know the
50# size of the image before compressing, so we have to do:
51# 1. Add an ovf file.
52# 2. Find the offset of the next member data.
53# 3. Make room for image data, allocating for the worst case.
54# 4. Write compressed image data into the tar.
55# 5. Add a tar entry with the actual image size.
56# 6. Shrink the tar to the actual size, aligned to 512 bytes.
57
58tar_file = file_path("test.ova")
59
60with tarfile.open(tar_file, "w") as tar:
61
62    # 1. Add an ovf file.
63
64    ovf_data = b"<xml/>"
65    ovf = tarfile.TarInfo("vm.ovf")
66    ovf.size = len(ovf_data)
67    tar.addfile(ovf, io.BytesIO(ovf_data))
68
69    # 2. Find the offset of the next member data.
70
71    offset = tar.fileobj.tell() + 512
72
73    # 3. Make room for image data, allocating for the worst case.
74
75    measure = qemu_img_measure("-O", "qcow2", src_disk)
76    tar.fileobj.truncate(offset + measure["required"])
77
78    # 4. Write compressed image data into the tar.
79
80    nbd_sock = file_path("nbd-sock", base_dir=iotests.sock_dir)
81    nbd_uri = "nbd+unix:///exp?socket=" + nbd_sock
82
83    # Use raw format to allow creating qcow2 directly into tar file.
84    with qemu_nbd_popen(
85            "--socket", nbd_sock,
86            "--export-name", "exp",
87            "--format", "raw",
88            "--offset", str(offset),
89            tar_file):
90
91        iotests.log("=== Target image info ===")
92        # Not img_info_log as it enforces imgfmt, but now we print info on raw
93        qemu_img_log("info", nbd_uri)
94
95        qemu_img(
96            "convert",
97            "-f", iotests.imgfmt,
98            "-O", "qcow2",
99            "-c",
100            src_disk,
101            nbd_uri)
102
103        iotests.log("=== Converted image info ===")
104        img_info_log(nbd_uri)
105
106        iotests.log("=== Converted image check ===")
107        qemu_img_log("check", nbd_uri)
108
109        iotests.log("=== Comparing to source disk ===")
110        qemu_img_log("compare", src_disk, nbd_uri)
111
112        actual_size = qemu_img_check(nbd_uri)["image-end-offset"]
113
114    # 5. Add a tar entry with the actual image size.
115
116    disk = tarfile.TarInfo("disk")
117    disk.size = actual_size
118    tar.addfile(disk)
119
120    # 6. Shrink the tar to the actual size, aligned to 512 bytes.
121
122    tar_size = offset + (disk.size + 511) & ~511
123    tar.fileobj.seek(tar_size)
124    tar.fileobj.truncate(tar_size)
125
126with tarfile.open(tar_file) as tar:
127    members = [{"name": m.name, "size": m.size, "offset": m.offset_data}
128               for m in tar]
129    iotests.log("=== OVA file contents ===")
130    iotests.log(members)
131