storage_file_probe: Treat qcow2 images with protocol drivers in backing store field as raw

qemu allows and in some cases uses protocol driver names ('file',
'host_device', 'nbd', ...) in the 'backing file format' field of a qcow
to denote a image where the dummy 'raw' driver was not used on top.

Adapt our backing store parser for such cases. The examples added in
previous patch show the difference in behaviour.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This commit is contained in:
Peter Krempa 2023-11-23 22:37:46 +01:00
parent 6fe9e35610
commit 156ddb43b1
4 changed files with 30 additions and 3 deletions

View File

@ -474,9 +474,15 @@ qcow2GetExtensions(const char *buf,
memcpy(tmp, buf + offset, len);
tmp[len] = '\0';
/* qemu and qemu-img allow using the protocol driver name inside
* of the format field in cases when the dummy 'raw' driver should
* not be created. Thus libvirt needs to consider anything that
* doesn't look like a format driver name to be a protocol driver
* directly and thus the image is in fact still considered raw
*/
*backingFormat = virStorageFileFormatTypeFromString(tmp);
if (*backingFormat <= VIR_STORAGE_FILE_NONE)
return -1;
*backingFormat = VIR_STORAGE_FILE_RAW;
break;
}

View File

@ -484,7 +484,7 @@ mymain(void)
VIR_STORAGE_FILE_QCOW2, EXP_PASS);
TEST_CHAIN("qcow2-protocol-backing-nbd",
abs_srcdir "/virstoragetestdata/images/qcow2-protocol-backing-nbd.qcow2",
VIR_STORAGE_FILE_QCOW2, EXP_FAIL);
VIR_STORAGE_FILE_QCOW2, EXP_PASS);
/* Qcow2 file with missing backing file but specified type */
TEST_CHAIN("qcow2-qcow2_missing",

View File

@ -1,6 +1,6 @@
path:ABS_SRCDIR/virstoragetestdata/images/qcow2-protocol-backing-file.qcow2
backingStoreRaw: raw
backingStoreRawFormat: <null>(-1)
backingStoreRawFormat: raw(1)
capacity: 1024
encryption: 0
relPath:<null>

View File

@ -0,0 +1,21 @@
path:ABS_SRCDIR/virstoragetestdata/images/qcow2-protocol-backing-nbd.qcow2
backingStoreRaw: nbd+tcp://example.org:6000/blah
backingStoreRawFormat: raw(1)
capacity: 10485760
encryption: 0
relPath:<null>
type:file
format:qcow2
protocol:none
hostname:<null>
path:blah
backingStoreRaw: <null>
backingStoreRawFormat: none(0)
capacity: 0
encryption: 0
relPath:<null>
type:network
format:raw
protocol:nbd
hostname:example.org