Commit Graph

159 Commits

Author SHA1 Message Date
Michal Privoznik
696a9faa8e lxc: Don't leak @veths in virLXCProcessStart
The individual strings are freed, but the array is never freed.

 8 bytes in 1 blocks are definitely lost in loss record 28 of 1,098
    at 0x4C2CE3F: malloc (vg_replace_malloc.c:298)
    by 0x4C2F1BF: realloc (vg_replace_malloc.c:785)
    by 0x52C9C92: virReallocN (viralloc.c:245)
    by 0x52C9D88: virExpandN (viralloc.c:294)
    by 0x23414D99: virLXCProcessSetupInterfaces (lxc_process.c:552)
    by 0x23417457: virLXCProcessStart (lxc_process.c:1356)
    by 0x2341F71C: lxcDomainCreateWithFiles (lxc_driver.c:1088)
    by 0x2341F805: lxcDomainCreate (lxc_driver.c:1123)
    by 0x55917EB: virDomainCreate (libvirt-domain.c:6534)
    by 0x1367D1: remoteDispatchDomainCreate (remote_daemon_dispatch_stubs.h:4434)
    by 0x1366EA: remoteDispatchDomainCreateHelper (remote_daemon_dispatch_stubs.h:4410)
    by 0x546FDF1: virNetServerProgramDispatchCall (virnetserverprogram.c:437)

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-07-26 14:18:06 +02:00
Daniel P. Berrangé
f14c37ce4c nwfilter: convert virt drivers to use public API for nwfilter bindings
Remove the callbacks that the nwfilter driver registers with the domain
object config layer. Instead make the current helper methods call into
the public API for creating/deleting nwfilter bindings.

Reviewed-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-06-26 18:17:23 +01:00
Anya Harter
031eb8f6dc events: add NULL check in virObjectEventStateQueue
And remove NULL checking from all callers.

Signed-off-by: Anya Harter <aharter@redhat.com>
2018-06-12 07:28:18 +02:00
John Ferlan
b04629b629 conf: Clean up object referencing for Add and Remove
When adding a new object to the domain object list, there should
have been 2 virObjectRef calls made one for each list into which
the object was placed to match the 2 virObjectUnref calls that
would occur during Remove as part of virHashRemoveEntry when
virObjectFreeHashData is called when the element is removed from
the hash table as set up in virDomainObjListNew.

Some drivers (libxl, lxc, qemu, and vz) handled this inconsistency
by calling virObjectRef upon successful return from virDomainObjListAdd
in order to use virDomainObjEndAPI when done with the returned @vm.
While others (bhyve, openvz, test, and vmware) handled this via only
calling virObjectUnlock upon successful return from virDomainObjListAdd.

This patch will "unify" the approach to use virDomainObjEndAPI
for any @vm successfully returned from virDomainObjListAdd.

Because list removal is so tightly coupled with list addition,
this patch fixes the list removal algorithm to return the object
as entered - "locked and reffed".  This way, the callers can then
decide how to uniformly handle add/remove success and failure.
This removes the onus on the caller to "specially handle" the
@vm during removal processing.

The Add/Remove logic allows for some logic simplification such
as in libxl where we can Remove the @vm directly rather than
needing to set a @remove_dom boolean and removing after the
libxlDomainObjEndJob completes as the @vm is locked/reffed.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Erik Skultety <eskultet@redhat.com>
2018-05-03 19:09:03 -04:00
Martin Kletzander
aa2c1a16ba lxc/: Remove spaces after casts
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
2018-05-03 22:31:36 +02:00
Daniel P. Berrangé
23ed8eb21d nwfilter: pass vm name in when instantiating filters
The vm name is not needed for any functional requirement, but it will be
useful when debugging problems to identify which VM is associated with a
filter, since UUID is not human friendly.

Reviewed-by: Jiri Denemark <jdenemar@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-05-03 17:00:57 +01:00
Daniel P. Berrangé
a2fd657b86 lxc: allow use of lxc:///system URI as preferred format
Historically we have used a bare lxc:/// URI for connecting to LXC. This
is different from our practice with QEMU, UML, Parallels, Libxl, BHyve
and VirtualBox drivers, which all use a path of '/system' or '/session'
or both.

By making LXC allow '/system', we have fully standardized on the use of
either '/system' or '/session' for all the stateful drivers that run
inside libvirtd.

Support for lxc:/// is of course maintained for back-compat.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-04-12 16:52:01 +01:00
John Ferlan
3f204e4de4 util: Alter virCloseCallback typedef to return void
Since virCloseCallbacksRun was ignoring the value anyway, let's
just change it to be a void function.

Signed-off-by: John Ferlan <jferlan@redhat.com>
Reviewed-by: Marc Hartmayer <mhartmay@linux.vnet.ibm.com>
2018-04-09 18:26:03 -04:00
John Ferlan
849b6a7b6a lxc: Use virDomainObjEndAPI after FindByName
For consistency, rather than open coding the Unref and Unlock,
just use the virDomainObjEndAPI API.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2018-04-02 09:38:19 -04:00
Daniel P. Berrangé
5b13570ab8 conf: introduce callback registration for domain net device allocation
Currently virt drivers will call directly into the network driver impl
to allocate domain interface devices where type=network. This introduces
a callback system to allow us to decouple the virt drivers from the
network driver.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
2018-02-09 11:05:10 +00:00
Michal Privoznik
cea3715b2e QoS: Set classes and filters in proper direction
Similarly to previous patch, for some types of interface domain
and host are on the same side of RX/TX barrier. In that case, we
need to set up the QoS differently. Well, swapped.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
2017-10-05 09:16:05 +02:00
Martin Kletzander
eaf2c9f891 Move machineName generation from virsystemd into domain_conf
It is more related to a domain as we might use it even when there is
no systemd and it does not use any dbus/systemd functions.  In order
not to use code from conf/ in util/ pass machineName in cgroups code
as a parameter.  That also fixes a leak of machineName in the lxc
driver and cleans up and de-duplicates some code.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2017-07-25 17:02:27 +02:00
Martin Kletzander
aa0dfb91d5 lxc: Make lxcProcessStop callable even without PID being available
This way the function can work as a central point of clean-up code and
we don't have to duplicate code.  And it works similarly to the qemu
driver.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2017-07-25 17:02:27 +02:00
Pavel Hrdina
e13e8808f9 security: don't relabel chardev source if virtlogd is used as stdio handler
In the case that virtlogd is used as stdio handler we pass to QEMU
only FD to a PIPE connected to virtlogd instead of the file itself.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1430988

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
2017-06-16 16:00:10 +02:00
John Ferlan
77a12987a4 Introduce virDomainChrSourceDefNew for virDomainChrDefPtr
Change the virDomainChrDef to use a pointer to 'source' and allocate
that pointer during virDomainChrDefNew.

This has tremendous "fallout" in the rest of the code which mainly
has to change source.$field to source->$field.

Signed-off-by: John Ferlan <jferlan@redhat.com>
2016-10-21 14:03:36 -04:00
Michal Privoznik
b7d2d4af2b src: Treat PID as signed
This initially started as a fix of some debug printing in
virCgroupDetect. However it turned out that other places suffer
from the similar problem. While dealing with pids, esp. in cases
where we cannot use pid_t for ABI stability reasons, we often
chose an unsigned integer type. This makes no sense as pid_t is
signed.
Also, new syntax-check rule is introduced so we won't repeat this
mistake.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-10-13 17:58:56 +08:00
Jiri Denemark
97a87333a0 Add helper for removing transient definition
The code for replacing domain's transient definition with the persistent
one is repeated in several places and we'll need to add one more. Let's
make a nice helper for it.

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
2016-09-08 22:25:22 +02:00
Erik Skultety
28e191a96c fs: Fix '<' comparison of value produced by logical not '!'
Commit da665fbd introduced the following condition to virLXCProcessEnsureRootFS
and openvzReadFSConf:

if (!(<some_var> = virDomainFSDefNew()) < 0)

which broke the build on fedora with GCC 5.3.1: "logical not is only applied to
the left hand side of comparison".

Signed-off-by: Erik Skultety <eskultet@redhat.com>
2016-07-19 09:38:40 +02:00
Olga Krishtal
da665fbd48 filesystem: adds possibility to use storage pool as fs source
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
2016-07-18 23:39:56 +03:00
Laine Stump
187920273c lxc: support setting host-side IP addresses/routes
(This patch had been pushed earlier in
commit cd5c9f21de, but was reverted in
commit 1549f16832 because it had been
accidentally pushed during the freeze for release 2.0.0)
2016-07-01 21:13:31 -04:00
Ján Tomko
1549f16832 Revert "lxc: support setting host-side IP addresses/routes"
This reverts commit cd5c9f21de.

This feature was accidentally pushed in the feature freeze.
2016-06-27 12:54:55 +02:00
Laine Stump
cd5c9f21de lxc: support setting host-side IP addresses/routes 2016-06-26 19:33:10 -04:00
Ján Tomko
8c40ede4a4 Do not check for domain liveness in virDomainObjSetDefTransient
Remove the live attribute and mark the definition as transient
whether the domain is runing or not.

There were only two callers left calling with live=false:
* testDomainStartState, where the domain already is active
  because we assigned vm->def->id just a few lines above the call
* virDomainObjGetPersistentDef, which now only calls
  virDomainObjSetDefTransient for an active domain
2016-06-06 08:34:22 +02:00
Ján Tomko
9b111048ad Clean up redundant usage of virDomainObjSetDefTransient
Commit 45ec297d from November 2010:
    Make state driver device hotplug/update actually transient
added virDomainObjSetDefTransient calls to the domain startup
function in several drivers.

In November 2011, commit 8866eed:
    Set aliases for LXC/UML console devices
added a call earlier in the startup function, without removing the
existing ones.

Also, in the UML driver it seems the function never did anything
useful - vm->def->id is set asynchronnously in umlNotifyEvent.
At the time of calling virDomainObjSetDefTransient with live=false,
vm->def->id was likely still -1, making the call a no-op.
2016-06-06 08:34:22 +02:00
Laine Stump
002b7704ff lxc: support <interface type='ethernet'>
This is identical to type='bridge', but without the "connect to a
bridge" part, so it can be handled by using the same functions (and
often even the same cases in switch statements), after renaming
virLXCProcessSetupInterfaceBridged() to virLXCProcessInterfaceTap()
and enhancing it to skip bridge-related items when brname == NULL.

To be truly useful, we need to support setting the ip address on the
host side veth as well as guest side veth (already supported for
type='bridge'), as well as setting the peer address for both.

The <script> element (supported by type='ethernet' in qemu) isn't
supported in this patch. An error is logged at domain start time if it
is encountered. This may be changed in a later patch.
2016-05-24 15:21:05 -04:00
Jovanka Gulicoska
b29e08dbe3 More usage of virGetLastErrorMessage
Convert to virGetLastErrorMessage() in the rest of the code
2016-05-19 15:17:03 -04:00
Laine Stump
75db9997a0 util: set vlan tag for macvtap passthrough mode on SRIOV VFs
SRIOV VFs used in macvtap passthrough mode can take advantage of the
SRIOV card's transparent vlan tagging. All the code was there to set
the vlan tag, and it has been used for SRIOV VFs used for hostdev
interfaces for several years, but for some reason, the vlan tag for
macvtap passthrough devices was stubbed out with a -1.

This patch moves a bit of common validation down to a lower level
(virNetDevReplaceNetConfig()) so it is shared by hostdev and macvtap
modes, and updates the macvtap caller to actually send the vlan config
instead of -1.
2016-05-10 14:04:19 -04:00
Cole Robinson
27f2b74782 lxc: explicitly error on interface type=ethernet
It isn't implemented and does not work:

error: internal error: guest failed to start: /usr/lib/libvirt/libvirt_lxc: option '--veth' requires an argument
syntax: /usr/lib/libvirt/libvirt_lxc [OPTIONS] ...

We previously threw an explicit error, but this changed in
22cff52a2b , which I suspect was
untested for LXC
2016-04-18 17:49:45 -04:00
Michal Privoznik
f3c47aafa4 virLXCProcessMonitorInitNotify: Initialize @inode
This is an error message I've just seen. Fix it by initializing
@inode.

  CC       lxc/libvirt_driver_lxc_impl_la-lxc_process.lo
lxc/lxc_process.c: In function 'virLXCProcessMonitorInitNotify':
lxc/lxc_process.c:767:23: error: 'inode' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     virDomainAuditInit(vm, initpid, inode);
                       ^

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2016-03-04 15:23:16 +01:00
Martin Kletzander
c3bd0019c0 systemd: Modernize machine naming
So, systemd-machined has this philosophy that machine names are like
hostnames and hence should follow the same rules.  But we always allowed
international characters in domain names.  Thus we need to modify the
machine name we are passing to systemd.

In order to change some machine names that we will be passing to systemd,
we also need to call TerminateMachine at the end of a lifetime of a
domain.  Even for domains that were started with older libvirt.  That
can be achieved thanks to virSystemdGetMachineNameByPID().  And because
we can change machine names, we can get rid of the inconsistent and
pointless escaping of domain names when creating machine names.

So this patch modifies the naming in the following way.  It creates the
name as <drivername>-<id>-<name> where invalid hostname characters are
stripped out of the name and if the resulting name is longer, it
truncates it to 64 characters.  That way we can start domains we
couldn't start before.  Well, at least on systemd.

To make it work all together, the machineName (which is needed only with
systemd) is saved in domain's private data.  That way the generation is
moved to the driver and we don't need to pass various unnecessary
arguments to cgroup functions.

The only thing this complicates a bit is the scope generation when
validating a cgroup where we must check both old and new naming, so a
slight modification was needed there.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1282846

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2016-02-05 16:11:50 +01:00
Daniel P. Berrange
1036ddadb2 conf: add caps to virDomainObjFormat/SaveStatus
The virDomainObjFormat and virDomainSaveStatus methods
both call into virDomainDefFormat, so should be providing
a non-NULL virCapsPtr instance.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-02-05 10:57:08 +00:00
Joao Martins
d239a5427f conf: add caps to virDomainDefFormat*
And use the newly added caps->host.netprefix (if it exists) for
interface names that match the autogenerated target names.

Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
2016-02-04 12:38:26 +00:00
Michal Privoznik
08da97bfb9 virNetDevMacVLanCreateWithVPortProfile: Rework to support multiple FDs
For the multiqueue on macvtaps we are going to need to open
the device multiple times. Currently, this is not supported.
Rework the function, so that upper layers can be reworked too.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-12-11 08:44:43 +01:00
Michal Privoznik
56e2171c6f virNetDevMacVLanCreateWithVPortProfile: Turn vnet_hdr into flag
So yet again one of integer arguments that we use as a boolean.
Since the argument count of the function is unbearably long
enough, lets turn those booleans into flags.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-12-11 08:42:49 +01:00
Jonathan Toppins
5c668a78d8 qemu: add udp interface support
Adds a new interface type using UDP sockets, this seems only applicable
to QEMU but have edited tree-wide to support the new interface type.

The interface type required the addition of a "localaddr" (local
address), this then maps into the following xml and qemu call.

<interface type='udp'>
  <mac address='52:54:00:5c:67:56'/>
  <source address='127.0.0.1' port='11112'>
    <local address='127.0.0.1' port='22222'/>
  </source>
  <model type='virtio'/>
  <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/>
</interface>

QEMU call:
	-net socket,udp=127.0.0.1:11112,localaddr=127.0.0.1:22222

Notice the xml "local" entry becomes the "localaddr" for the qemu call.

reference:
http://lists.gnu.org/archive/html/qemu-devel/2011-11/msg00629.html

Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2015-09-02 10:17:50 +02:00
ik.nitk
c27553b6e2 lxc: Inherit namespace feature
This patch adds feature for lxc containers to inherit namespaces.
This is very similar to what lxc-tools or docker provides.  Look
for "man lxc-start" and you will find that you can pass command
args as [ --share-[net|ipc|uts] name|pid ]. Or check out docker
networking option in which you can give --net=container:NAME_or_ID
as an option for sharing +namespace.

>From this patch you can add extra libvirt option to share
namespace in following way.

 <lxc:namespace>
   <lxc:sharenet type='netns' value='red'/>
   <lxc:shareipc type='pid' value='12345'/>
   <lxc:shareuts type='name' value='container1'/>
 </lxc:namespace>

The netns option is specific to sharenet. It can be used to
inherit from existing network namespace.

Co-authored: Daniel P. Berrange <berrange@redhat.com>
2015-08-26 11:28:30 +01:00
Peter Krempa
dbb0baa5a7 lxc: Don't accidentaly reset autostart flag in virLXCProcessCleanup
virDomainDeleteConfig is meant to delete the persistent config and thus
it resets vm->autostart. Copy parts of qemuProcessRemoveDomainStatus to
a new helper to avoid using the incorrect function.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1230071
2015-07-28 18:55:39 +02:00
Peter Krempa
88f6c007c3 cgroup: Drop resource partition from virSystemdMakeScopeName
The scope name, even according to our docs is
"machine-$DRIVER\x2d$VMNAME.scope" virSystemdMakeScopeName would use the
resource partition name instead of "machine-" if it was specified thus
creating invalid scope paths.

This makes libvirt drop cgroups for a VM that uses custom resource
partition upon reconnecting since the detected scope name would not
match the expected name generated by virSystemdMakeScopeName.

The error is exposed by the following log entry:

debug : virCgroupValidateMachineGroup:302 : Name 'machine-qemu\x2dtestvm.scope' for controller 'cpu' does not match 'testvm', 'testvm.libvirt-qemu' or 'machine-test-qemu\x2dtestvm.scope'

for a "/machine/test" resource and "testvm" vm.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1238570
2015-07-22 07:12:56 +02:00
Michal Privoznik
302146b16d lxc: Don't pass a local variable address randomly
So, recently I was testing the LXC driver. You know, startup some
domains. But to my surprise, I was not able to start a single one:

  virsh # start --console test
  error: Reconnected to the hypervisor
  error: Failed to start domain test
  error: internal error: guest failed to start: unexpected exit status 125

So I've start digging. It turns out, that in virExec(), when I printed
out the @cmd, I got strange values: *(cmd->outfdptr) was certainly not
valid FD number: it has random value of several millions. This
obviously made prepareStdFd(childout, STDOUT_FILENO) fail (line 611).
But outfdptr is set in virCommandSetOutputFD(). The only place within
LXC driver where the function is called is in
virLXCProcessBuildControllerCmd(). If you take a closer look at the
function it looks like this:

static virCommandPtr
virLXCProcessBuildControllerCmd(virLXCDriverPtr driver,
                                ..
                                int logfd,
                                const char *pidfile)
{
    ...
    virCommandSetOutputFD(cmd, &logfd);
    virCommandSetErrorFD(cmd, &logfd);
    ...
}

Yes, you guessed it. @logfd is passed into the function by value.
However, in the function we try to get its address (an address of a
local variable) which is no longer valid once function is finished and
stack is cleaned. Therefore when cmd->outfdptr is evaluated at any
point after this function, we may get a random number, depending on
what's currently on the stack. Of course, this may work sometimes too
- it depends on the compiler how it arranges the code, when the stack
is wiped out.

In order to fix this, lets pass a pointer to @logfd instead of
figuring out (wrong) its value in a function.

The bug was introduced in e1de5521.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2015-07-01 17:49:35 +02:00
Laine Stump
451547a422 util: clean up #includes of virnetdevopenvswitch.h
virnetdevopenvswitch.h declares a few functions that can be called to
add ports to and remove them from OVS bridges, and retrieve the
migration data for a port. It does not contain any data definitions
that are used by domain_conf.h. But for some reason, domain_conf.h
virnetdevopenvswitch.h should be directly #including it. This adds a
few lines to the project, but saves all the files that don't need it
from the extra computing, and makes the dependencies more clear cut.
2015-03-18 14:43:47 -04:00
Luyao Huang
8e6492f298 lxc: Fix container cleanup for LXCProcessStart
Jumping to the cleanup label prior to starting the container failed to
properly clean everything up that is handled by the virLXCProcessCleanup
which is called if virLXCProcessStop is called on failure after the
container properly starts. Most importantly is prior to this patch none
of the stop/release hooks, host device reattachment, and network cleanup
(that is reverse of virLXCProcessSetupInterfaces).

Signed-off-by: Luyao Huang <lhuang@redhat.com>
2015-02-13 13:44:52 -05:00
John Ferlan
2b8e018ad8 lxc: Modify/add some debug messages
Modify the VIR_DEBUG message in virLXCProcessCleanup to make it clearer
about the path.  Also add some more VIR_DEBUG messages in virLXCProcessStart
in order to help debug error flow.
2015-02-13 13:44:52 -05:00
Luyao Huang
72129907c1 lxc: Move console checks in LXCProcessStart
https://bugzilla.redhat.com/show_bug.cgi?id=1176503

Move the two console checks - one for zero nconsoles present and the
other for an invalid console type to earlier in the processing rather than
getting after performing some setup that has to be undone for what amounts
to an invalid configuration.

This resolves the above bug since it's not not possible to have changed
the security labels when we cause the configuration check failure.
2015-02-13 13:44:52 -05:00
Erik Skultety
c3d9d3bbc9 security: introduce virSecurityManagerCheckAllLabel function
We do have a check for valid per-domain security model, however we still
do permit an invalid security model for a domain's device (those which
are specified with <source> element).
This patch introduces a new function virSecurityManagerCheckAllLabel
which compares user specified security model against currently
registered security drivers. That being said, it also permits 'none'
being specified as a device security model.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1165485
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2015-02-13 14:37:54 +01:00
Cédric Bosdonnat
88a1b54208 Clear dynamic seclabels on LXCProcessStart failure
commit a58e1cb4 didn't fix the bug if the security_default_confined is
not set to 1. We now clean up even if there is no seclabel defined or
the default one.
2015-02-09 10:29:00 +01:00
Luyao Huang
4cef725782 lxc: fix double close handshakefds[1]
Signed-off-by: Luyao Huang <lhuang@redhat.com>
2015-02-04 15:42:43 +01:00
Daniel P. Berrange
0a8addc103 lxc: only write XML once for lxc controller
Currently when launching the LXC controller we first write out
the plain, inactive XML configuration, then launch the controller,
then replace the file with the live status XML configuration.
By good fortune this hasn't caused any problems other than some
misleading error messages during failure scenarios.

This simplifies the code so it only writes out the XML once and
always writes the live status XML. To do this we need to handshake
with the child process, to make execution pause just before exec()
so we can write the XML status with the child PID present.
2015-01-27 13:57:02 +00:00
Daniel P. Berrange
e1de552150 lxc: re-arrange startup synchronization sequence with controller
Currently the lxc controller process itself is responsible for
daemonizing itself into the background and writing out its pid
file. The lxc driver would fork the controller and then attempt
to connect to the lxc monitor. This connection would only
succeed after the controller has backgrounded itself, setup
cgroups and written its pid file, so startup was race free.

The problem is that we need to delay create of the cgroups to
much later, such that we can tell systemd the container init
pid when we create the cgroups. If we delay cgroup creation
though the current synchronization won't work.

A second problem is that the controller needs the XML config
of the guest. Currently we write out the plain virDomainDefPtr
XML before starting the controller, and then later replace it
with the full virDomainObjPtr status XML. This is kind of gross
and also means that the controller doesn't get a record of the
live XML config right away. This means it doesn't have a record
of the veth device names either and so can't give that info
to systemd when creating the cgroups.

To address this we change the startup sequencing. The goal
is that we want to get the PID as soon as possible, before
the LXC controller even starts. So we stop letting the LXC
controller daemonize itself, and instead use virCommand's
built-in capabilities. This daemonizes and writes the PID
before LXC controller is exec'd. So the driver can read
the PID as soon as virCommandRun returns. It is no longer
safe to connect to the monitor or detect the cgroups though.

Fortunately the LXC controller already has a second point
of synchronization. Immediately before its  event loop
starts running, it performs a handshake with the driver.
So we move the opening of the monitor connection and cgroup
detection after this synchronization point.
2015-01-27 13:57:02 +00:00
Daniel P. Berrange
a5979e3374 lxc: don't build pidfile string multiple times
Build the pidfile string once when starting a guest and then
use the same string thereafter. This will benefit following
patches which need the pidfile string in more situations.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-01-27 13:57:02 +00:00
Daniel P. Berrange
7b1ba9566b Remove use of nwfilterPrivateData from nwfilter driver
The nwfilter driver can rely on its global state instead
of the connect private data.
2015-01-27 12:02:03 +00:00