Currently VolOpen notifies the user of a potentially non-fatal failure by
returning -2 and logging a VIR_WARN or VIR_INFO. Unfortunately most
callers treat -2 as fatal but don't actually report any message with
the error APIs.
Rename the VOL_OPEN_ERROR flag to VOL_OPEN_NOERROR. If NOERROR is specified,
we preserve the current behavior of returning -2 (there's only one caller
that wants this).
However in the default case, only return -1, and actually use the error
APIs. Fix up a couple callers as a result.
Coverity complains about a possible leak of seclabel if
!sec_managers[i]->drv->domainGenSecurityLabel is true
and the seclabel might be overwritten by the next iteration
of the loop.
This leak should never happen, because every security driver
has domainGenSecurityLabel defined.
A future patch will merge virStorageFileMetadata and virStorageSource,
but I found it easier to do if both structs use the same information
for tracking whether a source file needs encryption keys.
* src/util/virstoragefile.h (_virStorageFileMetadata): Prepare
full encryption struct instead of just a bool.
* src/storage/storage_backend_fs.c (virStorageBackendProbeTarget):
Use transfer semantics.
* src/storage/storage_backend_gluster.c
(virStorageBackendGlusterRefreshVol): Likewise.
* src/util/virstoragefile.c (virStorageFileGetMetadataInternal):
Populate struct.
(virStorageFileFreeMetadata): Adjust clients.
* tests/virstoragetest.c (testStorageChain): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Now that each virStorageSource can track allocation information,
and given that we already have the information without extra
syscalls, it's easier to just always populate the information
directly into the struct than it is to sometimes pass the address
of the struct members down the call chain.
* src/storage/storage_backend.h (virStorageBackendUpdateVolInfo)
(virStorageBackendUpdateVolTargetInfo)
(virStorageBackendUpdateVolTargetInfoFD): Update signature.
* src/storage/storage_backend.c (virStorageBackendUpdateVolInfo)
(virStorageBackendUpdateVolTargetInfo)
(virStorageBackendUpdateVolTargetInfoFD): Always populate struct
members instead.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskMakeDataVol): Update client.
* src/storage/storage_backend_fs.c (virStorageBackendProbeTarget)
(virStorageBackendFileSystemRefresh)
(virStorageBackendFileSystemVolRefresh): Likewise.
* src/storage/storage_backend_gluster.c
(virStorageBackendGlusterRefreshVol): Likewise.
* src/storage/storage_backend_logical.c
(virStorageBackendLogicalMakeVol): Likewise.
* src/storage/storage_backend_mpath.c
(virStorageBackendMpathNewVol): Likewise.
* src/storage/storage_backend_scsi.c
(virStorageBackendSCSINewLun): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
One of the features of qcow2 is that a wrapper file can have
more capacity than its backing file from the guest's perspective;
what's more, sparse files make tracking allocation of both
the active and backing file worthwhile. As such, it makes
more sense to show allocation numbers for each file in a chain,
and not just the top-level file. This sets up the fields for
the tracking, although it does not modify XML to display any
new information.
* src/util/virstoragefile.h (_virStorageSource): Add fields.
* src/conf/storage_conf.h (_virStorageVolDef): Drop redundant
fields.
* src/storage/storage_backend.c (virStorageBackendCreateBlockFrom)
(createRawFile, virStorageBackendCreateQemuImgCmd)
(virStorageBackendCreateQcowCreate): Update clients.
* src/storage/storage_driver.c (storageVolDelete)
(storageVolCreateXML, storageVolCreateXMLFrom, storageVolResize)
(storageVolWipeInternal, storageVolGetInfo): Likewise.
* src/storage/storage_backend_fs.c (virStorageBackendProbeTarget)
(virStorageBackendFileSystemRefresh)
(virStorageBackendFileSystemVolResize)
(virStorageBackendFileSystemVolRefresh): Likewise.
* src/storage/storage_backend_logical.c
(virStorageBackendLogicalMakeVol)
(virStorageBackendLogicalCreateVol): Likewise.
* src/storage/storage_backend_scsi.c
(virStorageBackendSCSINewLun): Likewise.
* src/storage/storage_backend_mpath.c
(virStorageBackendMpathNewVol): Likewise.
* src/storage/storage_backend_rbd.c
(volStorageBackendRBDRefreshVolInfo)
(virStorageBackendRBDCreateImage): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskMakeDataVol)
(virStorageBackendDiskCreateVol): Likewise.
* src/storage/storage_backend_sheepdog.c
(virStorageBackendSheepdogBuildVol)
(virStorageBackendSheepdogParseVdiList): Likewise.
* src/storage/storage_backend_gluster.c
(virStorageBackendGlusterRefreshVol): Likewise.
* src/conf/storage_conf.c (virStorageVolDefFormat)
(virStorageVolDefParseXML): Likewise.
* src/test/test_driver.c (testOpenVolumesForPool)
(testStorageVolCreateXML, testStorageVolCreateXMLFrom)
(testStorageVolDelete, testStorageVolGetInfo): Likewise.
* src/esx/esx_storage_backend_iscsi.c (esxStorageVolGetXMLDesc):
Likewise.
* src/esx/esx_storage_backend_vmfs.c (esxStorageVolGetXMLDesc)
(esxStorageVolCreateXML): Likewise.
* src/parallels/parallels_driver.c (parallelsAddHddByVolume):
Likewise.
* src/parallels/parallels_storage.c (parallelsDiskDescParseNode)
(parallelsStorageVolDefineXML, parallelsStorageVolCreateXMLFrom)
(parallelsStorageVolDefRemove, parallelsStorageVolGetInfo):
Likewise.
* src/vbox/vbox_tmpl.c (vboxStorageVolCreateXML)
(vboxStorageVolGetXMLDesc): Likewise.
* tests/storagebackendsheepdogtest.c (test_vdi_list_parser):
Likewise.
* src/phyp/phyp_driver.c (phypStorageVolCreateXML): Likewise.
A fairly smooth transition. And now that domain disks and
storage volumes share a common struct, it opens the doors for
a future patch to expose more details in the XML for both
objects.
* src/conf/storage_conf.h (_virStorageVolTarget): Delete.
(_virStorageVolDef): Use common type.
* src/conf/storage_conf.c (virStorageVolDefFree)
(virStorageVolTargetDefFormat): Update clients.
* src/storage/storage_backend.h: Likewise.
* src/storage/storage_backend.c
(virStorageBackendDetectBlockVolFormatFD)
(virStorageBackendUpdateVolTargetInfo)
(virStorageBackendUpdateVolTargetInfoFD): Likewise.
* src/storage/storage_backend_fs.c (virStorageBackendProbeTarget):
Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Another step towards unification of structures. While we might
not expose everything in XML via domain disk as we do for
storage volume pointer, both places want to deal with (at least
part of) the backing chain; therefore, moving towards a single
struct usable from both contexts will make the backing chain
code more reusable.
* src/conf/storage_conf.h (_virStoragePerms)
(virStorageTimestamps): Move...
* src/util/virstoragefile.h: ...here.
(_virStorageSource): Add more fields.
* src/util/virstoragefile.c (virStorageSourceClear): Clean
additional fields.
Signed-off-by: Eric Blake <eblake@redhat.com>
Some preparatory work before consolidating storage volume
structs with the rest of virstoragefile. Making these
changes allows a volume target to be much closer to (a
subset of) the virStorageSource struct.
Making perms be a pointer allows it to be optional if we
have a storage pool that doesn't expose permissions in a
way we can access. It also allows future patches to
optionally expose permissions details learned about a disk
image via domain <disk> listings, rather than just
limiting it to storage volume listings.
Disk partition types was only used by internal code to
control what type of partition to create when carving up
an MS-DOS partition table storage pool (and is not used
for GPT partition tables or other storage pools). It was
not exposed in volume XML, and as it is more closely
related to extent information of the overall block device
than it is to the <target> information describing the host
file. Besides, if we ever decide to expose it in XML down
the road, we can move it back as needed.
* src/conf/storage_conf.h (_virStorageVolTarget): Change perms to
pointer, enhance comments. Move partition type...
(_virStorageVolSource): ...here.
* src/conf/storage_conf.c (virStorageVolDefFree)
(virStorageVolDefParseXML, virStorageVolTargetDefFormat): Update
clients.
* src/storage/storage_backend_fs.c (createFileDir): Likewise.
* src/storage/storage_backend.c (virStorageBackendCreateBlockFrom)
(virStorageBackendCreateRaw, virStorageBackendCreateExecCommand)
(virStorageBackendUpdateVolTargetInfoFD): Likewise.
* src/storage/storage_backend_logical.c
(virStorageBackendLogicalCreateVol): Likewise.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskMakeDataVol)
(virStorageBackendDiskPartTypeToCreate): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Now that we have a dedicated type for representing a disk source,
we might as well parse and format directly into that type instead
of piecemeal into pointers to members of the type.
* src/conf/domain_conf.h (virDomainDiskSourceDefFormatInternal)
(virDomainDiskSourceDefParse): Rename...
(virDomainDiskSourceFormat, virDomainDiskSourceParse): ...and
compress signatures.
* src/conf/domain_conf.c (virDomainDiskSourceParse)
(virDomainDiskSourceFormat): Rewrite to use common struct.
(virDomainDiskSourceDefFormat): Delete.
(virDomainDiskDefParseXML, virDomainDiskDefFormat): Update
callers.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefParseXML)
(virDomainSnapshotDiskDefFormat): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
The phyp code claims that it wants a non-zero value, but actually
enforces a capacity of zero. It has been this way since commit
ebc46fe in June 2010. Bummer that it has my name as the committer
- I guess I should have been much more stubborn about not blindly
taking someone else's 1600-line patch.
* src/phyp/phyp_driver.c (phypStorageVolCreateXML): Use correct
logic.
Signed-off-by: Eric Blake <eblake@redhat.com>
On all the places where qemuAgentComand() was called, we did a check
for errors in the reply. Unfortunately, some of the places called
qemuAgentCheckError() without checking for non-null reply which might
have resulted in a crash.
So this patch makes the error-checking part of qemuAgentCommand()
itself, which:
a) makes it look better,
b) makes the check mandatory and, most importantly,
c) checks for the errors if and only if it is appropriate.
This actually fixes a potential crashers when qemuAgentComand()
returned 0, but reply was NULL. Having said that, it *should* fix the
following bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1058149
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Noticed during my work on storage struct cleanups.
* src/storage/storage_backend_disk.c
(virStorageBackendDiskPartBoundaries): Fix spelling errors.
Signed-off-by: Eric Blake <eblake@redhat.com>
Now that we have a common struct, it's time to start using it!
Since external snapshots make a longer backing chain, it is
only natural to use the same struct for the file created by
the snapshot as what we use for <domain> disks.
* src/conf/snapshot_conf.h (_virDomainSnapshotDiskDef): Use common
struct instead of open-coded duplicate fields.
* src/conf/snapshot_conf.c (virDomainSnapshotDiskDefClear)
(virDomainSnapshotDiskDefParseXML, virDomainSnapshotAlignDisks)
(virDomainSnapshotDiskDefFormat)
(virDomainSnapshotDiskGetActualType): Adjust clients.
* src/qemu/qemu_conf.c (qemuTranslateSnapshotDiskSourcePool):
Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDiskGetSourceString)
(qemuDomainSnapshotCreateInactiveExternal)
(qemuDomainSnapshotPrepareDiskExternalOverlayActive)
(qemuDomainSnapshotPrepareDiskExternal)
(qemuDomainSnapshotPrepare)
(qemuDomainSnapshotCreateSingleDiskActive): Likewise.
* src/storage/storage_driver.c
(virStorageFileInitFromSnapshotDef): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Move some functions out of domain_conf for use in the next
patch where snapshot starts to directly use structs in
virstoragefile.
* src/conf/domain_conf.c (virDomainDiskDefFree)
(virDomainDiskSourcePoolDefParse): Adjust callers.
(virDomainDiskSourceDefClear, virDomainDiskSourcePoolDefFree)
(virDomainDiskAuthClear): Move...
* src/util/virstoragefile.c (virStorageSourceClear)
(virStorageSourcePoolDefFree, virStorageSourceAuthClear): ...and
rename.
* src/conf/domain_conf.h (virDomainDiskAuthClear): Drop
declaration.
* src/qemu/qemu_conf.c (qemuTranslateDiskSourcePool): Adjust
caller.
* src/util/virstoragefile.h: Declare them.
* src/libvirt_private.syms (virstoragefile.h): Export them.
Signed-off-by: Eric Blake <eblake@redhat.com>
The only remaining reason that virt-login-shell was trying to
link against virstoragefile was because of a call to
virStorageFileFormatTypeToString when spawning a qemu-nbd
process - but setuid processes shouldn't be spawning qemu-nbd.
* src/util/virfile.c (virFileLoopDeviceAssociate)
(virFileNBDDeviceAssociate): Cripple in setuid builds.
* src/Makefile.am (libvirt_setuid_rpc_client_la_SOURCES):
Drop virstoragefile from the list.
Signed-off-by: Eric Blake <eblake@redhat.com>
The code in virstoragefile.c is getting more complex as I
consolidate backing chain handling code. But for the setuid
virt-login-shell, we don't need to crawl backing chains. It's
easier to audit things for setuid security if there are fewer
files involved, so this patch moves the one function that
virFileOpen() was actually relying on to also live in virfile.c.
* src/util/virstoragefile.c (virStorageFileIsSharedFS)
(virStorageFileIsSharedFSType): Move...
* src/util/virfile.c (virFileIsSharedFS, virFileIsSharedFSType):
...to here, and rename.
(virFileOpenAs): Update caller.
* src/security/security_selinux.c
(virSecuritySELinuxSetFileconHelper)
(virSecuritySELinuxSetSecurityAllLabel)
(virSecuritySELinuxRestoreSecurityImageLabelInt): Likewise.
* src/security/security_dac.c
(virSecurityDACRestoreSecurityImageLabelInt): Likewise.
* src/qemu/qemu_driver.c (qemuOpenFileAs): Likewise.
* src/qemu/qemu_migration.c (qemuMigrationIsSafe): Likewise.
* src/util/virstoragefile.h: Adjust declarations.
* src/util/virfile.h: Likewise.
* src/libvirt_private.syms (virfile.h, virstoragefile.h): Move
symbols as appropriate.
Signed-off-by: Eric Blake <eblake@redhat.com>
With this patch, all information related to a host resource in
a storage file backing chain now lives in util/virstoragefile.h.
The next step will be to consolidate various places that have
been tracking backing chain details to all use a common struct.
The changes to tools/Makefile.am were made necessary by the
fact that virstorageencryption includes uses of libxml, and is
now pulled in by inclusion from virstoragefile.h. No
additional libraries are linked into the final image, and in
comparison, the build of the setuid library in src/Makefile.am
already was using LIBXML_CFLAGS via AM_CFLAGS.
* src/conf/domain_conf.h (virDomainDiskSourceDef): Move...
* src/util/virstoragefile.h (virStorageSource): ...and rename.
* src/conf/domain_conf.c (virDomainDiskSourceDefClear)
(virDomainDiskAuthClear): Adjust clients.
* tools/Makefile.am (virt_login_shell_CFLAGS)
(virt_host_validate_CFLAGS): Add libxml headers.
Signed-off-by: Eric Blake <eblake@redhat.com>
This one is a relatively easy move. We don't ever convert the
enum to or from strings (it is inferred from other elements in
the xml, rather than directly represented).
* src/conf/domain_conf.h (virDomainDiskSecretType): Move...
* src/util/virstoragefile.h (virStorageSecreteType): ...and
rename.
* src/conf/domain_conf.c (virDomainDiskSecretType): Drop unused
enum conversion.
(virDomainDiskAuthClear, virDomainDiskDefParseXML)
(virDomainDiskDefFormat): Adjust clients.
* src/qemu/qemu_command.c (qemuGetSecretString): Likewise.
* src/qemu/qemu_conf.c (qemuTranslateDiskSourcePoolAuth):
Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
Another struct being moved to util. This one doesn't have as
much use yet, thankfully.
* src/conf/domain_conf.h (virDomainDiskSourcePoolMode)
(virDomainDiskSourcePoolDef): Move...
* src/util/virstoragefile.h (virStorageSourcePoolMode)
(virStorageSourcePoolDef): ...and rename.
* src/conf/domain_conf.c (virDomainDiskSourcePoolDefFree)
(virDomainDiskSourceDefClear, virDomainDiskSourcePoolDefParse)
(virDomainDiskDefParseXML, virDomainDiskSourceDefParse)
(virDomainDiskSourceDefFormatInternal)
(virDomainDiskDefForeachPath, virDomainDiskSourceIsBlockType):
Adjust clients.
* src/qemu/qemu_conf.c (qemuTranslateDiskSourcePool): Likewise.
* src/libvirt_private.syms (domain_conf.h): Move symbols...
(virstoragefile.h): ...as appropriate.
Signed-off-by: Eric Blake <eblake@redhat.com>
Encryption keys can be associated with each source file in a
backing chain; as such, this file belongs more in util/ where
it can be used by virstoragefile.h.
* src/conf/storage_encryption_conf.h: Rename...
* src/util/virstorageencryption.h: ...to this.
* src/conf/storage_encryption_conf.c: Rename...
* src/util/virstorageencryption.c: ...to this.
* src/Makefile.am (ENCRYPTION_CONF_SOURCES, CONF_SOURCES)
(UTIL_SOURCES): Update to new file names.
* src/libvirt_private.syms: Likewise.
* src/conf/domain_conf.h: Update client.
* src/conf/storage_conf.h: Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
In order to reuse the newly-created host-side disk struct in
the virstoragefile backing chain code, I first have to move
it to util/. This starts the process, by first moving the
security label structures.
* src/conf/domain_conf.h (virDomainDefGenSecurityLabelDef)
(virDomainDiskDefGenSecurityLabelDef, virSecurityLabelDefFree)
(virSecurityDeviceLabelDefFree, virSecurityLabelDef)
(virSecurityDeviceLabelDef): Move...
* src/util/virseclabel.h: ...to new file.
(virSecurityLabelDefNew, virSecurityDeviceLabelDefNew): Rename the
GenSecurity functions.
* src/qemu/qemu_process.c (qemuProcessAttach): Adjust callers.
* src/security/security_manager.c (virSecurityManagerGenLabel):
Likewise.
* src/security/security_selinux.c
(virSecuritySELinuxSetSecurityFileLabel): Likewise.
* src/util/virseclabel.c: New file.
* src/conf/domain_conf.c: Move security code, and fix fallout.
* src/Makefile.am (UTIL_SOURCES): Build new file.
* src/libvirt_private.syms (domain_conf.h): Move symbols...
(virseclabel.h): ...to new section.
Signed-off-by: Eric Blake <eblake@redhat.com>
In 'make syntax-check', we have a rule that prevents layering
violations between the various files in src. However, we
forgot to treat conf/ and the more recently-added access/ as
lower-level directories, and were not detecting cases where
they might have used a driver file. Also, it's not nice that
qemu can use storage/ but none of the other drivers could do so.
* cfg.mk (sc_prohibit_cross_inclusion): Tighten rules for conf/
and access/, let all other drivers use storage/.
Signed-off-by: Eric Blake <eblake@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1072714
Use the "gluster" command line tool to retrieve information about remote
volumes on a gluster server to allow storage pool source lookup.
Unfortunately gluster doesn't provide a management library so that we
could use that directly, instead the RPC calls are hardcoded in the
command line tool.
Extract the NFS related stuff into a separate function and tidy up the
rest of the code so we can reuse it to add gluster backend detection.
Additionally avoid reporting of errors from "showmount" and return an
empty source list instead. This will help when adding other detection
backends.
According to our documentation the "key" value has the following
meaning: "Providing an identifier for the volume which identifies a
single volume." The currently used keys for gluster volumes consist of
the gluster volume name and file path. This can't be considered unique
as a different storage server can serve a volume with the same name.
Unfortunately I wasn't able to figure out a way to retrieve the gluster
volume UUID which would avoid the possibility of having two distinct
keys identifying a single volume.
Use the full URI as the key for the volume to avoid the more critical
ambiguity problem and document the possible change to UUID.
While running virdbustest, it was found that valgrind pointed out
the following memory leaks:
==9996== 17 (8 direct, 9 indirect) bytes in 1 blocks are definitely lost in loss record 9 of 36
==9996== at 0x4A069EE: malloc (vg_replace_malloc.c:270)
==9996== by 0x4A06B62: realloc (vg_replace_malloc.c:662)
==9996== by 0x4C6B587: virReallocN (viralloc.c:245)
==9996== by 0x4C6B6AE: virExpandN (viralloc.c:294)
==9996== by 0x4C82B54: virDBusMessageDecodeArgs (virdbus.c:907)
==9996== by 0x4C83463: virDBusMessageDecode (virdbus.c:1141)
==9996== by 0x402C45: testMessageArrayRef (virdbustest.c:273)
==9996== by 0x404E71: virtTestRun (testutils.c:201)
==9996== by 0x401C2D: mymain (virdbustest.c:479)
==9996== by 0x4055ED: virtTestMain (testutils.c:789)
==9996== by 0x3E6CE1ED1C: (below main) (libc-start.c:226)
==9996==
==9996== 28 (16 direct, 12 indirect) bytes in 1 blocks are definitely lost in loss record 12 of 36
==9996== at 0x4A06BE0: realloc (vg_replace_malloc.c:662)
==9996== by 0x4C6B587: virReallocN (viralloc.c:245)
==9996== by 0x4C6B6AE: virExpandN (viralloc.c:294)
==9996== by 0x4C82B54: virDBusMessageDecodeArgs (virdbus.c:907)
==9996== by 0x4C83463: virDBusMessageDecode (virdbus.c:1141)
==9996== by 0x402C45: testMessageArrayRef (virdbustest.c:273)
==9996== by 0x404E71: virtTestRun (testutils.c:201)
==9996== by 0x401C2D: mymain (virdbustest.c:479)
==9996== by 0x4055ED: virtTestMain (testutils.c:789)
==9996== by 0x3E6CE1ED1C: (below main) (libc-start.c:226)
==9996==
Signed-off-by: Eric Blake <eblake@redhat.com>
'virsh help event' included a summary line "event - (null)"
due to a misnamed info field.
* tools/virsh-domain.c (info_event): Use correct name.
* tools/virsh-network.c (info_network_event): Likewise.
Signed-off-by: Eric Blake <eblake@redhat.com>
On failures, virBhyveProcessStart() does not cleanup network
interfaces that could be created by virBhyveProcessBuildBhyveCmd(),
which results in a leaked tap device.
To fix that, extract network cleanup code to bhyveNetCleanup()
and use it in cleanup stage of virBhyveProcessStart().
When virStorageFileGetMetadata is called with NULL path argument, the
invalid pointer boils down through the recursive worker and is caught by
virHashAddEntry which is thankfully resistant to NULL arguments. As it
doesn't make sense to pursue backing chains of NULL volumes, exit
earlier.
This was noticed in the virt-aahelper-test with a slightly modified
codebase.
The libgfapi function glfs_fini doesn't tolerate NULL pointers. Add a
check on the error paths as it's possible to crash libvirtd if the
gluster volume can't be initialized.
Using any of these chars [:*?"<>|] in a filename is forbidden on
Windows and breaks git operations on Windows as git is not able
to create those files/directories on clone or pull.
Because some of them can be used in UNIX filenames they tend to
creep into filenames; especially : in PCI/SCSI device names that
are used as filenames in test cases.
Windows doesn't allow : in filenames.
Commit 6fdece9a33 added files with a : in
their names. This broke git operations on Windows as git is not able to
create those files on clone or pull.
Replace : with - in the offending filenames and adapt the test case.
As the tested Linux specific code expects the files to exist with : in
their path use symlinks to provide the name that way.
virNodeDeviceListCaps will always return empty for a pci nodedevice,
actually it should return 'pci'.
It is because the loop variable ncaps isn't increased.
Introduced by commit be2636f.
https://bugzilla.redhat.com/show_bug.cgi?id=1081932
Signed-off-by: Jincheng Miao <jmiao@redhat.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
