Commit Graph

15624 Commits

Author SHA1 Message Date
Eric Blake
119eb4a140 maint: update to latest gnulib, for mingw improvements
On Fedora 20, mingw-headers has switched over to winpthreads as
the provider for its <pthread.h>.  winpthreads is notorious for
providing a less-than-stellar header, and needs several workarounds
before it can be used in a project assuming POSIX semantics.  While
we still use Windows primitives rather than pthread when compiling
for mingw, this update will make it possible to switch to mingw
pthreads.

* .gnulib: Update to latest, for mingw fixes.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-23 15:21:59 -07:00
Osier Yang
88ae5dc759 storage: Fix the memory leak
The return value of virGetFCHostNameByWWN is a strdup'ed string.
Also add comments to declare that the caller should take care of
freeing it.
2014-01-23 21:39:05 +08:00
Osier Yang
7519958735 util: Fix the indention
Left in the git cache without commit before pushing. Pushed under
build breaker and trivial rule.
2014-01-23 18:16:11 +08:00
Osier Yang
2b66504ded util: Add "shareable" field for virSCSIDevice struct
Unlike the host devices of other types, SCSI host device XML supports
"shareable" tag. This patch introduces it for the virSCSIDevice struct
for a later patch use (to detect if the SCSI device is shareable when
preparing the SCSI host device in QEMU driver).
2014-01-23 17:52:33 +08:00
Osier Yang
2340f0196f storage: Fix autostart of pool with "fc_host" type adapter
The "checkPool" is a bit different for pool with "fc_host"
type source adapter, since the vHBA it's based on might be
not created yet (it's created by "startPool", which is
involked after "checkPool" in storageDriverAutostart). So it
should not fail, otherwise the "autostart" of the pool will
fail either.

The problem is easy to reproduce:
    * Enable "autostart" for the pool
    * Restart libvirtd service
    * Check the pool's state
2014-01-23 17:50:29 +08:00
Bing Bu Cao
2310e631cd Fix buffer size in linuxNodeGetCPUstats
94f8205 added a space to the string but didn't change the buffer size.

Signed-off-by: Bing Bu Cao <mars@linux.vnet.ibm.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2014-01-23 10:29:14 +01:00
Osier Yang
6b29eb848f storage: Add document for possible problem on volume detection
For pool which relies on remote resources, such as a "iscsi" type
pool, since how long it takes to export the corresponding devices
to host's sysfs is really depended, it could depend on the network
connection, it also could depend on the host's udev procedures. So
it's likely that the volumes are not able to be detected during pool
starting process, polling the sysfs doesn't work, since we don't
know how much time is best for the polling, and even worse, the
volumes could still be not detected or partly not detected even after
the polling.  So we end up with a documentation to prompt the fact,
in virsh manual.

And as a small improvement, let's explicitly say no LUNs found in
the debug log in that case.
2014-01-23 13:47:55 +08:00
Osier Yang
ae2860b4c6 util: Correct the NUMA node range checking
There are 2 issues here: First we shouldn't add "1" to the return
value of numa_max_node(), since the semanteme of the error message
was changed, it's not saying about the number of total NUMA nodes
anymore.  Second, the value of "bit" is the position of the first
bit which exceeds either numa_max_node() or NUMA_NUM_NODES, it can
be any number in the range, so saying "bigger than $bit" is quite
confused now. For example, assuming there is a NUMA machine which
has 10 NUMA nodes, and one specifies the "nodeset" as "0,5,88",
the error message will be like:

Nodeset is out of range, host cannot support NUMA node bigger than 88

It sounds like all NUMA node number less than 88 is fine, but
actually the maximum NUMA node number the machine supports is 9.

This patch fixes the issues by removing the addition with "1" and
simplifies the error message as "NUMA node $bit is out of range".
Also simplifies the comparision in the while loop by getting the
smaller one of numa_max_node() and NUMA_NUM_NODES up front.
2014-01-23 13:19:56 +08:00
Eric Blake
7f2d27d1e3 api: require write permission for guest agent interaction
I noticed that we allow virDomainGetVcpusFlags even for read-only
connections, but that with a flag, it can require guest agent
interaction.  It is feasible that a malicious guest could
intentionally abuse the replies it sends over the guest agent
connection to possibly trigger a bug in libvirt's JSON parser,
or withhold an answer so as to prevent the use of the agent
in a later command such as a shutdown request.  Although we
don't know of any such exploits now (and therefore don't mind
posting this patch publicly without trying to get a CVE assigned),
it is better to err on the side of caution and explicitly require
full access to any domain where the API requires guest interaction
to operate correctly.

I audited all commands that are marked as conditionally using a
guest agent.  Note that at least virDomainFSTrim is documented
as needing a guest agent, but that such use is unconditional
depending on the hypervisor (so the existing domain:fs_trim ACL
should be sufficient there, rather than also requirng domain:write).
But when designing future APIs, such as the plans for obtaining
a domain's IP addresses, we should copy the approach of this patch
in making interaction with the guest be specified via a flag, and
use that flag to also require stricter access checks.

* src/libvirt.c (virDomainGetVcpusFlags): Forbid guest interaction
on read-only connection.
(virDomainShutdownFlags, virDomainReboot): Improve docs on agent
interaction.
* src/remote/remote_protocol.x
(REMOTE_PROC_DOMAIN_SNAPSHOT_CREATE_XML)
(REMOTE_PROC_DOMAIN_SET_VCPUS_FLAGS)
(REMOTE_PROC_DOMAIN_GET_VCPUS_FLAGS, REMOTE_PROC_DOMAIN_REBOOT)
(REMOTE_PROC_DOMAIN_SHUTDOWN_FLAGS): Require domain:write for any
conditional use of a guest agent.
* src/xen/xen_driver.c: Fix clients.
* src/libxl/libxl_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/lxc/lxc_driver.c: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-22 16:52:41 -07:00
Jean-Baptiste Rouault
bb85da2cb1 vbox: add support for v4.2.20+ and v4.3.4+
Bugs have been found in the VirtualBox API C bindings. These bugs have
been fixed in versions 4.2.20 and 4.3.4. However, the changes in the
C bindings are incompatible with the vbox_CAPI_v4_2.h and vbox_CAPI_v4_3.h
files which are bundled in libvirt source code.
This is why the following patch adds vbox_CAPI_v4_2_20.h and
vbox_CAPI_v4_3_4.h.

The actual underlying problem here is that until now,
libvirt assumed that VirtualBox API can only change between minor
versions (4.2 -> 4.3), but we have a case here where it changed
(or got fixed) between patch versions (4.2.18 -> 4.2.20).

This patch makes the VBOX_API_VERSION represent the full API
version number (i.e 4002 => 4002000) so there are specific version
numbers for Vbox 4.2.20 (4002020) and 4.3.4 (4003004)
2014-01-22 23:12:52 +01:00
Peter Krempa
7f0fd42741 qemu: Avoid crash in qemuDiskGetActualType
Libvirtd would crash if a domain contained an empty cdrom drive of
type='volume' as the disk def->srcpool member would be dereferenced. Fix
it by checking if the source pool is present before dereferencing it.

Also alter tests to catch this issue in the future.

Reported by: Kevin Shanahan
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1056328
2014-01-22 11:33:31 +01:00
Osier Yang
deb924dda8 Doc: Add "note" for node-memory-tune
To let the user know the command onlys work for KSM under Linux.
2014-01-22 18:01:08 +08:00
Osier Yang
39a0e32867 Doc: Improve the document for nodesuspend
Explicitly lists the possible values for "--target" option;
Gets rid of the confused strings like "Suspend-to-RAM";
Emphasises the node *has to* be suspended in the time duration
specified by "--duration". And rewords the entire document a
bit according to the API's implementation and document.
2014-01-22 17:59:12 +08:00
Michael Chapman
881a2cff0d virtlockd: make re-exec more robust
- Use $XDG_RUNTIME_DIR for re-exec state file when running unprivileged.

- argv[0] may not contain a full path to the binary, however it should
  contain something that can be looked up in the PATH. Use execvp() to
  do path lookup on re-exec.

- As per list discussion [1], ignore --daemon on re-exec.

[1] https://www.redhat.com/archives/libvir-list/2013-December/msg00514.html

Signed-off-by: Michael Chapman <mike@very.puzzling.org>
2014-01-22 10:44:41 +01:00
Claudio Bley
2a27d6a4f2 docs: refer to the correct event ID for DomainEventIOErrorReasonCallback
s/_ID_IO_ERROR/_ID_IO_ERROR_REASON/
2014-01-22 10:37:14 +01:00
Osier Yang
b5bac8d059 virsh: Fix the string breaking style 2014-01-22 13:56:47 +08:00
Bing Bu Cao
94f8205359 linuxNodeGetCPUStats: Correctly handle cpu prefix
To retrieve node cpu statistics on Linux system, the
linuxNodeGetCPUstats function simply uses STRPREFIX() to match the cpuid
with the one read from /proc/stat. However, as the file is read line by
line it may happen, that some CPUs share the same prefix. So if user
requested stats for the first CPU, which is offline, then there's no
cpu1 in the stats file so the one that we match is cpu10. Which is
obviously wrong. Fortunately, the IDs are terminated by a space, so we
can utilize that.

Signed-off-by: Bing Bu Cao <mars@linux.vnet.ibm.com>
2014-01-21 17:24:03 +01:00
Daniel P. Berrange
9d6f26e57c Honour prefix in wireshark install dir
Trying to run

  $ ./configure --prefix=$HOME/usr/libvirt-git
  $ make install

results in libvirt trying to install in /usr/lib/wireshark/plugins/....
with predictable amounts of fail. The configure script should not be
hardcoding /usr/lib by default but rather honour $libdir

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-01-21 16:19:27 +00:00
Peter Krempa
3d1e9e4779 qemu: snapshot: Forbid snapshots when backing is a scsi passthrough disk
https://bugzilla.redhat.com/show_bug.cgi?id=1034993

SCSI passthrough disks (<disk .. device="lun">) can't be used as backing
for snapshots. Currently with upstream qemu the vm crashes on such
attempt.

This patch adds a early check to catch an attempt to do such a snapshot
and rejects it right away. qemu will fix the issue but this will let us
control the error message.
2014-01-21 17:05:21 +01:00
Laine Stump
00e9d6071b build: add $(prefix) to SYSTEMD_UNIT_DIR
I noticed this problem when adding systemd support to netcf, because I
setup the configure.ac to automatically prefer using systemd over
initscripts when possible - although I had copied the
install-data-local target from the example of libvirt's
"libvirt-guests" service more or less verbatim, "make distcheck" would
fail because it was trying to install the service file directly into
/lib/systemd/system rather than into
/home/user/some/unimportant/name/lib/systemd/system.

This is caused by the install/uninstall rules for the systemd unit
files relying on $(DESTDIR) pointing the installed files to the right
place, but in reality $(DESTDIR) is empty during this part of make
distcheck - it instead sets $(prefix) with the toplevel directory used
for its test build/install/uninstall cycle.

(This problem hasn't been seen when running "make distcheck" in
libvirt because libvirt will never build/install systemd support
unless explicitly told to do so on the configure commandline, and
"make distcheck" doesn't put the "--with-initscript=..." option on the
configure commandline.)

I verified that the same problem does exist in libvirt by modifying
libvirt's configure.ac to set:

  init_systemd=yes
  with_init_script=systemd+redhat

This forces a build/install of the systemd unit files during
distcheck, which yields an error like this:

/usr/bin/install -c -m 644 virtlockd.service \
  /lib/systemd/system/
libtool: install: warning: relinking `libvirt-qemu.la'
/usr/bin/install: cannot remove '/lib/systemd/system/virtlockd.service': Permission denied
make[4]: *** [install-systemd] Error 1

After adding $(prefix) to all the definitions of SYSTEMD_UNIT_DIR,
make distcheck now completes successfully with the modified
configure.ac, and the above lines change to something like this:

/usr/bin/install -c -m 644 virtlockd.service \
  /home/laine/devel/libvirt/libvirt-1.2.1/_inst/lib/systemd/system/
2014-01-21 13:19:46 +02:00
Peter Krempa
55bbb011b9 qemu: snapshot: Avoid libvirtd crash when qemu crashes while snapshotting
We shouldn't access the domain definition while we are in the monitor
section as the domain is unlocked. Additionally after we exit from the
monitor we need to check if the VM is still alive. Not doing so resulted
in a crash if qemu exits while attempting to do an external VM snapshot.
2014-01-21 11:42:01 +01:00
Francesco Romani
08d07e5fd8 spice: expose the QEMU disable file transfer option
spice-server offers an API to disable file transfer messages
on the agent channel between the client and the guest.
This is supported in qemu through the disable-agent-file-xfer option.

This patch exposes this option to libvirt.
Adds a new element 'filetransfer', with one property,
'enable', which accepts a boolean.
Default is enabled, for backward compatibility.

Depends on the capability exported in the first patch of the series.

Signed-off-by: Francesco Romani <fromani@redhat.com>
2014-01-21 11:35:41 +01:00
Francesco Romani
19bbc81276 spice: detect if qemu can disable file transfer
spice-server offers an API to disable file transfer messages
on the agent channel between the client and the guest.
This is supported in qemu through the disable-agent-file-xfer option.

This patch detects if QEMU supports this option, and add
a capability if does.

Signed-off-by: Francesco Romani <fromani@redhat.com>
2014-01-21 11:35:40 +01:00
Martin Kletzander
5ce90b3f2d lxc: Fix coverity
Commit 399394ab74 removed some coverity
comments which skipped the dead code, so add them back.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-01-21 09:04:44 +01:00
Gao feng
399394ab74 lxc: allow to setup throttle blkio cgroup through virsh
With this patch,user can set throttle blkio cgroup for
lxc domain through virsh tool.

Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2014-01-21 09:33:00 +08:00
Wout Mertens
4fbfac851e Add test for transient disk support in VMX files
--001a11c3e84c4130bc04f03cda95
Content-Type: text/plain; charset=ISO-8859-1

From: Wout Mertens <Wout.Mertens@gmail.com>

Adds test for transient disk translation in vmx files
2014-01-20 09:47:43 -07:00
Roman Bogorodskiy
881c6c0047 Use AC_PATH_PROG to search for dmidecode
This is useful in certain circumstances, for example when
libvirtd is being executed by FreeBSD rc script, it cannot find
dmidecode installed from FreeBSD ports because it doesn't have
/usr/local (default prefix for ports) in PATH.
2014-01-20 09:34:53 -07:00
Yuto KAWAMURA(kawamuray)
bad1cbe1b8 Add sample output of Wireshark dissector
Add directory tools/wireshark/samples/ and
libvirt-sample.pdml which is sample output of dissector.
2014-01-20 17:10:00 +01:00
Yuto KAWAMURA(kawamuray)
4f32c5f793 Introduce Libvirt Wireshark dissector
Introduce Wireshark dissector plugin which adds support to Wireshark
for dissecting libvirt RPC protocol.
Added following files to build Wireshark dissector from libvirt source
tree.
* tools/wireshark/*: Source tree of Wireshark dissector plugin.

Added followings to configure.ac or Makefile.am.
configure.ac
* --with-wireshark-dissector: Enable support for building Wireshark
  dissector.
* --with-ws-plugindir: Specify wireshark plugin directory that dissector
  will installed.
* Added tools/wireshark/{Makefile,src/Makefile} to  AC_CONFIG_FILES.
Makefile.am
* Added tools/wireshark/ to SUBDIR.
2014-01-20 17:09:41 +01:00
Thorsten Behrens
a1cbe4b5a9 Make syntax check notice assignments w/o surrounding spaces. 2014-01-20 14:35:26 +01:00
Thorsten Behrens
721949059b maint: align whitespaces with project conventions. 2014-01-20 14:35:08 +01:00
Jiri Denemark
b70c093ffa virpcitest: Test virPCIDeviceDetach failure
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 14:21:41 +01:00
Jiri Denemark
b803b29c1a virpcimock: Add PCI driver which always fails
Such driver can be used to make sure PCI APIs fail properly.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 14:21:33 +01:00
Jiri Denemark
bbeadb820c virpcitest: More tests for device detach and reattach
Especially for devices that are not bound to any driver.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 14:14:19 +01:00
Jiri Denemark
508b566ec2 virpcimock: Mock /sys/bus/pci/drivers_probe
This file is used by PCI detach and reattach APIs to probe for a driver
that handles a specific device.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 13:58:04 +01:00
Jiri Denemark
124affae84 pci: Publish some internal code for virpcitest
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 13:58:04 +01:00
Jiri Denemark
44bfe3574a virpcitest: Show PCI device tested by each test
For example:

 ...
 5) testVirPCIDeviceIsAssignable(0005:90:01.0)      ... OK
 6) testVirPCIDeviceIsAssignable(0001:01:00.0)      ... OK

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 13:58:04 +01:00
Jincheng Miao
df8022721e qemu: Don't detach devices if passthrough doesn't work
https://bugzilla.redhat.com/show_bug.cgi?id=1046919

If none (KVM, VFIO) of the supported PCI passthrough methods is known to
work on a host, it's better to fail right away with a nice error message
rather than letting attachment fail with a more cryptic message such as

    Failed to bind PCI device '0000:07:05.0' to vfio-pci: No such device

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 13:58:04 +01:00
Jiri Denemark
d8ab981bdd pci: Fix failure paths in detach
https://bugzilla.redhat.com/show_bug.cgi?id=1046919

Since commit v0.9.0-47-g4e8969e (released in 0.9.1) some failures during
device detach were reported to callers of virPCIDeviceBindToStub as
success. For example, even though a device seemed to be detached

    virsh # nodedev-detach pci_0000_07_05_0 --driver vfio
    Device pci_0000_07_05_0 detached

one could find similar message in libvirt logs:

    Failed to bind PCI device '0000:07:05.0' to vfio-pci: No such device

This patch fixes these paths and also avoids overwriting real errors
with errors encountered during a cleanup phase.
2014-01-20 13:58:04 +01:00
Jiri Denemark
c982e5e84f pci: Make reattach work for unbound devices
https://bugzilla.redhat.com/show_bug.cgi?id=1046919

When a PCI device is not bound to any driver, reattach should just
trigger driver probe rather than failing with

    Invalid device 0000:00:19.0 driver file
    /sys/bus/pci/devices/0000:00:19.0/driver is not a symlink

While virPCIDeviceGetDriverPathAndName was documented to return success
and NULL driver and path when a device is not attached to any driver but
didn't do so. Thus callers could not distinguish unbound devices from
failures.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2014-01-20 13:58:04 +01:00
Gao feng
0728d4721b qemu: allow to setup throttle blkio cgroup through virsh
With this patch, user can setup throttle blkio cgroup
through virsh for qemu domain.

Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2014-01-20 10:52:49 +08:00
Gao feng
8bbf1133ce virsh: add setting throttle blkio cgroup option to blkiotune
With this patch, user can setup the throttle blkio cgorup
for domain through the virsh cmd, such as:

virsh blkiotune domain1 --device-read-bytes-sec /dev/sda1,1000000,/dev/sda2,2000000
--device-write-bytes-sec /dev/sda1,1000000 --device-read-iops-sec /dev/sda1,10000
--device-write-iops-sec /dev/sda1,10000,/dev/sda2,0

This patch also add manpage for these new options.

Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2014-01-20 10:52:47 +08:00
Gao feng
3b431929a2 blkio: Setting throttle blkio cgroup for domain
This patch introduces virCgroupSetBlkioDeviceReadIops,
virCgroupSetBlkioDeviceWriteIops,
virCgroupSetBlkioDeviceReadBps and
virCgroupSetBlkioDeviceWriteBps,

we can use these interfaces to set up throttle
blkio cgroup for domain.

This patch also adds the new throttle blkio cgroup
elements to the test xml.

Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2014-01-20 10:52:44 +08:00
Gao feng
fb2fbc6d7b domain: introduce xml elements for throttle blkio cgroup
This patch introduces new xml elements under <blkiotune>,
we use these new elements to setup the throttle blkio
cgroup for domain. The new blkiotune node looks like this:

<blkiotune>
  <device>
    <path>/path/to/block</path>
    <weight>1000</weight>
    <read_iops_sec>10000</read_iops_sec>
    <write_iops_sec>10000</write_iops_sec>
    <read_bytes_sec>1000000</read_bytes_sec>
    <write_bytes_sec>1000000</write_bytes_sec>
  </device>
</blkiotune>

Signed-off-by: Guan Qiang <hzguanqiang@corp.netease.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2014-01-20 10:52:42 +08:00
Christophe Fergeau
8eaa25f2d6 doc: Add missing space in <clock> documentation 2014-01-17 18:18:55 +01:00
Michal Privoznik
d1fdecb624 virSecuritySELinuxSetFileconHelper: Don't fail on read-only NFS
https://bugzilla.redhat.com/show_bug.cgi?id=996543

When starting up a domain, the SELinux labeling is done depending on
current configuration. If the labeling fails we check for possible
causes, as not all labeling failures are fatal. For example, if the
labeled file is on NFS which lacks SELinux support, the file can still
be readable to qemu process. These cases are distinguished by the errno
code: NFS without SELinux support returns EOPNOTSUPP. However, we were
missing one scenario. In case there's a read-only disk on a read-only
NFS (and possibly any FS) and the labeling is just optional (not
explicitly requested in the XML) there's no need to make the labeling
error fatal. In other words, read-only file on read-only NFS can fail to
be labeled, but be readable at the same time.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-01-17 13:35:01 +01:00
Eric Blake
42358e3a0a maint: replace remaining virLib*Error with better names
Finish the cleanup of libvirt.c; all uses of virLib*Error have
now been converted to more canonical conventions.

* src/libvirt.c: Use virReportError in remaining errors.
(virLibConnError, virLibDomainError): Delete unused macros.
* cfg.mk (msg_gen_function): Drop unused names.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-16 12:30:59 -07:00
Eric Blake
323c2cc46c maint: simplify driver registration at startup
We had a lot of repetition of errors that would occur if we
ever register too many drivers; this is unlikely to occur
unless we start adding a lot of new hypervisor modules, but
if it does occur, it's better to have uniform handling of the
situation, so that a one-line change is all that would be
needed if we decide that an internal error is not the best.

* src/libvirt.c (virDriverCheckTabMaxReturn): New define.
(virRegister*Driver): Use it for less code duplication.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-16 12:29:25 -07:00
Eric Blake
27553573f2 maint: clean up error reporting in migration
The choice of error message and category was not consistent
in the migration code; furthermore, the use of virLibConnError
is no longer necessary now that we have a generic virReportError.

* src/qemu/qemu_migration.c (virDomainMigrate*): Prefer
virReportError over virLibConnError.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-16 12:28:17 -07:00
Eric Blake
c8ed177af4 maint: don't lose error on canceled migration
While auditing the error reporting, I noticed that migration
had some issues.  Some of the static helper functions tried
to call virDispatchError(), even though their caller will also
report the error.  Also, if a migration is cancelled early
because a uri was not set, we did not guarantee that the finish
stage would not overwrite the first error message.

* src/qemu/qemu_migration.c (doPeer2PeerMigrate2)
(doPeer2PeerMigrate3): Preserve first error when cancelling.
* src/libvirt.c (virDomainMigrateVersion3Full): Likewise.
(virDomainMigrateVersion1, virDomainMigrateVersion2)
(virDomainMigrateDirect): Avoid redundant error dispatch.
(virDomainMigrateFinish2, virDomainMigrateFinish3)
(virDomainMigrateFinish3Params): Don't report error on cleanup
path.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-16 12:26:54 -07:00