If veth device allocation has a fatal error, the veths
array may contain NULL device names. Avoid calling the
virNetDevVethDelete function on such names.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

During container cleanup there is a race where the kernel may
have destroyed the veth device before we try to set it offline.
This causes log error messages. Given that we're about to
delete the device entirely, setting it offline is pointless.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The problem is described by [0] but its effect on libvirt is that
starting a container with a full distro running systemd after having
stopped it simply fails.

The container cleanup now calls the machined Terminate function to make
sure that everything is in order for the next run.

 [0]: https://bugs.freedesktop.org/show_bug.cgi?id=68370

If upgrading from a libvirt that is older than 1.0.5, we can
not assume that vm->def->resource is non-NULL. This bogus
assumption caused libvirtd to crash
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Make the virCgroupNewMachine method try to use systemd-machined
first. If that fails, then fallback to using the traditional
cgroup setup code path.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

By setting the default partition in libvirt_lxc it is not
visible when querying the live XML. Move setting of the
default partition into libvirtd virLXCProcessStart
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

When detecting cgroups we must honour any controllers
whitelist the driver may have.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Instead of requiring drivers to use a combination of calls
to virCgroupNewDetect and virCgroupIsValidMachine, combine
the two into virCgroupNewDetectMachine
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Commit 'c8695053' resulted in the following:

Coverity error seen in the output:
    ERROR: REVERSE_INULL
    FUNCTION: lxcProcessAutoDestroy

Due to the 'dom' being checked before 'dom->persistent' since 'dom'
is already dereferenced prior to that.

Currently the LXC driver creates the VM's cgroup prior to
forking, and then libvirt_lxc moves the child process
into the cgroup. This won't work with systemd whose APIs
do the creation of cgroups + attachment of processes atomically.

Fortunately we simply move the entire cgroups setup into
the libvirt_lxc child process. We make it take place before
fork'ing into the background, so by the time virCommandRun
returns in the LXC driver, the cgroup is guaranteed to be
present.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Use the new virCgroupNewDetect function to determine cgroup
placement of existing running VMs. This will allow the legacy
cgroups creation APIs to be removed entirely
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Instead of returning errno values, change the virCgroupKill*
APIs to fully report errors.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

With the majority of fields in the virLXCDriverPtr struct
now immutable or self-locking, there is no need for practically
any methods to be using the LXC driver lock. Only a handful
of helper APIs now need it.

The 'driver->caps' pointer can be changed on the fly. Accessing
it currently requires the global driver lock. Isolate this
access in a single helper, so a future patch can relax the
locking constraints.

Currently the virLXCDriverPtr struct contains an wide variety
of data with varying access needs. Move all the static config
data into a dedicated virLXCDriverConfigPtr object. The only
locking requirement is to hold the driver lock, while obtaining
an instance of virLXCDriverConfigPtr. Once a reference is held
on the config object, it can be used completely lockless since
it is immutable.

NB, not all APIs correctly hold the driver lock while getting
a reference to the config object in this patch. This is safe
for now since the config is never updated on the fly. Later
patches will address this fully.

Merge the virCommandPreserveFD / virCommandTransferFD methods
into a single virCommandPasFD method, and use a new
VIR_COMMAND_PASS_FD_CLOSE_PARENT to indicate their difference
in behaviour
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Wire up the new virDomainCreate{XML}WithFiles methods in the
LXC driver, so that FDs get passed down to the init process.

The lxc_container code needs to do a little dance in order
to renumber the file descriptors it receives into linear
order, starting from STDERR_FILENO + 1.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Similarly to VIR_STRDUP, we want the OOM error to be reported in
VIR_ALLOC and friends.

Found with 'git grep "= 1"'.

The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.

Historically QEMU/LXC guests have been placed in a cgroup layout
that is

   $LOCATION-OF-LIBVIRTD/libvirt/{qemu,lxc}/$VMNAME

This is bad for a number of reasons

 - The cgroup hierarchy gets very deep which seriously
   impacts kernel performance due to cgroups scalability
   limitations.

 - It is hard to setup cgroup policies which apply across
   services and virtual machines, since all VMs are underneath
   the libvirtd service.

To address this the default cgroup location is changed to
be

    /system/$VMNAME.{lxc,qemu}.libvirt

This puts virtual machines at the same level in the hierarchy
as system services, allowing consistent policy to be setup
across all of them.

This also honours the new resource partition location from the
XML configuration, for example

  <resource>
    <partition>/virtualmachines/production</partitions>
  </resource>

will result in the VM being placed at

    /virtualmachines/production/$VMNAME.{lxc,qemu}.libvirt

NB, with the exception of the default, /system, path which
is intended to always exist, libvirt will not attempt to
auto-create the partitions in the XML. It is the responsibility
of the admin/app to configure the partitions. Later libvirt
APIs will provide a way todo this.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Instead of calling virCgroupForDomain every time we need
the virCgrouPtr instance, just do it once at Vm startup
and cache a reference to the object in virLXCDomainObjPrivatePtr
until shutdown of the VM. Removing the virCgroupPtr from
the LXC driver state also means we don't have stale mount
info, if someone mounts the cgroups filesystem after libvirtd
has been started
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virCgroupMounted method is badly named, since a controller can be
mounted, but disabled in the current object. Rename the method to be
virCgroupHasController. Also make it tolerant to a  NULL virCgroupPtr
and out-of-range controller index, to avoid duplication of these
checks in all callers
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This patch is the result of running:

for i in $(git ls-files | grep -v html | grep -v \.po$ ); do
  sed -i -e "s/virDomainXMLConf/virDomainXMLOption/g" -e "s/xmlconf/xmlopt/g" $i
done

and a few manual tweaks.

Currently the LXC container code has two codepaths, depending on
whether there is a <filesystem> element with a target path of '/'.
If we automatically add a <filesystem> device with src=/ and dst=/,
for any container which has not specified a root filesystem, then
we only need one codepath for setting up the filesystem.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Some of the LXC callbacks did not lock the virDomainObjPtr
instance. This caused transient errors like

error: Failed to start domain busy-mount
error: cannot rename file '/var/run/libvirt/lxc/busy-mount.xml.new' as '/var/run/libvirt/lxc/busy-mount.xml': No such file or directory

as 2 threads tried to update the status file concurrently
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The naming used in the RPC protocols for the LXC monitor and
lock daemon confused the script used to generate systemtap
helper functions. Rename the LXC monitor protocol symbols to
reduce confusion. Adapt the gensystemtap.pl script to cope
with the LXC monitor / lock daemon naming conversions.

This has no functional impact on RPC wire protocol, since
names are only used in the C layer
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If an LXC domain failed to start because of a bogus SELinux
label, virLXCProcessStart would call VIR_CLOSE(0) by mistake.
This is because the code which initializes the member of the
ttyFDs array to -1 got moved too far away from the place where
the array is first allocated.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The virCaps structure gathered a ton of irrelevant data over time that.
The original reason is that it was propagated to the XML parser
functions.

This patch aims to create a new data structure virDomainXMLConf that
will contain immutable data that are used by the XML parser. This will
allow two things we need:

1) Get rid of the stuff from virCaps

2) Allow us to add callbacks to check and add driver specific stuff
after domain XML is parsed.

This first attempt removes pointers to private data allocation functions
to this new structure and update all callers and function that require
them.

This fixes the build on Debian Wheezy which otherwise fails with:

  CC     libvirt_driver_lxc_impl_la-lxc_process.lo
  lxc/lxc_process.c: In function 'virLXCProcessGetNsInode':
  lxc/lxc_process.c:648:5: error: implicit declaration of function 'stat' [-Werror=implicit-function-declaration]
  lxc/lxc_process.c:648:5: error: nested extern declaration of 'stat' [-Werror=nested-externs]
  cc1: all warnings being treated as errors

To allow the efficient correlation of container audit messages
with host hosts, include the pid namespace inode in audit
messages.

Currently we rely on a VIR_ERROR message being logged by the
virRaiseError function to report LXC startup errors. This gives
the right message, but is rather ugly and can be truncated
if lots of log messages are written. Change the LXC controller
to explicitly print any virErrorPtr message to stderr. Then
change the driver to skip over anything that looks like a log
message.

The result is that this

error: Failed to start domain busy
error: internal error guest failed to start: 2013-03-04 19:46:42.846+0000: 1734: info : libvirt version: 1.0.2
2013-03-04 19:46:42.846+0000: 1734: error : virFileLoopDeviceAssociate:600 : Unable to open /root/disk.raw: No such file or directory

changes to

error: Failed to start domain busy
error: internal error guest failed to start: Unable to open /root/disk.raw: No such file or directory
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

As a step towards making virDomainObjList thread-safe turn it
into an opaque virObject, preventing any direct access to its
internals.

As part of this a new method virDomainObjListForEach is
introduced to replace all existing usage of virHashForEach

The APIs names for accessing the domain list object are
very inconsistent. Rename them all to have a standard
virDomainObjList prefix.