This migration cookie is meant for two purposes. The first is to be sent
in begin phase from source to destination to let it know we support new
implementation of VIR_MIGRATE_NON_SHARED_{DISK,INC} so destination can
start NBD server. Then, the second purpose is, destination can let us
know, on which port the NBD server is running.

As a side effect, this also fixes reporting disk migration process.
It was added to memory migration progress, which was wrong. Disk
progress has dedicated fields in virDomainJobInfo structure.

Since closeCallbacks were turned into virObjectLockable, we can no
longer call virQEMUCloseCallbacks APIs from within a registered close
callback.

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

To avoid confusion between 'virCapsPtr' and 'qemuCapsPtr'
do some renaming of various fucntions/variables. All
instances of 'qemuCapsPtr' are renamed to 'qemuCaps'. To
avoid that clashing with the 'qemuCaps' typedef though,
rename the latter to virQEMUCaps.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The functionality provided in virchrdev.c (previously virconsole.c) is
applicable to other types of character devices besides consoles, such
as channels.  This patch is just code motion, renaming things such as
"console" or "pty", instead using more general terms such as
"character device" or "device path".

This is just code motion, in preparation to rename identifiers to be
less console-specific.

Replace the following names

 * struct qemu_snap_remove  with virQEMUSnapRemovePtr
 * struct qemu_snap_reparent with virQEMUSnapReparentPtr
 * struct qemu_save_header with virQEMUSaveHeaderPtr
 * enum qemu_save_formats with virQEMUSaveFormat
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Remove the obsolete 'qemud' naming prefix and underscore
based type name. Introduce virQEMUDriverPtr as the replacement,
in common with LXC driver naming style

Currently, if user calls virDomainAbortJob we just issue
'migrate_cancel' and hope for the best. However, if user calls
the API in wrong phase when migration hasn't been started yet
(perform phase) the cancel request is just ignored. With this
patch, the request is remembered and as soon as perform phase
starts, migration is cancelled.

The new external system checkpoints will require an async job while the
snapshot is taken. This patch adds QEMU_ASYNC_JOB_SNAPSHOT to track this
job type.

Technically, we should not be re-probing any file that qemu might
be currently writing to.  As such, we should cache the backing
file chain prior to starting qemu.  This patch adds the cache,
but does not use it until the next patch.

Ultimately, we want to also store the chain in domain XML, so that
it is remembered across libvirtd restarts, and so that the only
kosher way to modify the backing chain of an offline domain will be
through libvirt API calls, but we aren't there yet.  So for now, we
merely invalidate the cache any time we do a live operation that
alters the chain (block-pull, block-commit, external disk snapshot),
as well as tear down the cache when the domain is not running.

* src/conf/domain_conf.h (_virDomainDiskDef): New field.
* src/conf/domain_conf.c (virDomainDiskDefFree): Clean new field.
* src/qemu/qemu_domain.h (qemuDomainDetermineDiskChain): New
prototype.
* src/qemu/qemu_domain.c (qemuDomainDetermineDiskChain): New
function.
* src/qemu/qemu_driver.c (qemuDomainAttachDeviceDiskLive)
(qemuDomainChangeDiskMediaLive): Pre-populate chain.
(qemuDomainSnapshotCreateSingleDiskActive): Uncache chain before
snapshot.
* src/qemu/qemu_process.c (qemuProcessHandleBlockJob): Update
chain after block pull.

Using VIR_DOMAIN_XML_MIGRATABLE flag, one can request domain's XML
configuration that is suitable for migration or save/restore. Such XML
may contain extra run-time stuff internal to libvirt and some default
configuration may be removed for better compatibility of the XML with
older libvirt releases.

This flag may serve as an easy way to get the XML that can be passed
(after desired modifications) to APIs that accept custom XMLs, such as
virDomainMigrate{,ToURI}2 or virDomainSaveFlags.

https://www.gnu.org/licenses/gpl-howto.html recommends that
the 'If not, see <url>.' phrase be a separate sentence.

* tests/securityselinuxhelper.c: Remove doubled line.
* tests/securityselinuxtest.c: Likewise.
* globally: s/;  If/.  If/

The current qemu capabilities are stored in a virBitmapPtr
object, whose type is exposed to callers. We want to store
more data besides just the flags, so we need to move to a
struct type. This object will also need to be reference
counted, since we'll be maintaining a cache of data per
binary. This change introduces a 'qemuCapsPtr' virObject
class. Most of the change is just renaming types and
variables in all the callers
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

This has several benefits:
1. Future snapshot-related code has a definite place to go (and I
_will_ be adding some)
2. Snapshot errors now use the VIR_FROM_DOMAIN_SNAPSHOT error
classification, which has been underutilized (previously only in
libvirt.c)

* src/conf/domain_conf.h, domain_conf.c: Split...
* src/conf/snapshot_conf.h, snapshot_conf.c: ...into new files.
* src/Makefile.am (DOMAIN_CONF_SOURCES): Build new files.
* po/POTFILES.in: Mark new file for translation.
* src/vbox/vbox_tmpl.c: Update caller.
* src/esx/esx_driver.c: Likewise.
* src/qemu/qemu_command.c: Likewise.
* src/qemu/qemu_domain.h: Likewise.

Previously, qemu did not respond to monitor commands during migration if
the limit was too high. This prevented us from raising the limit
earlier. The qemu issue seems to be fixed (according to my testing) and
we may remove the 32Mb/s limit.

Switch virDomainObjPtr to use the virObject APIs for reference
counting. The main change is that virObjectUnref does not return
the reference count, merely a bool indicating whether the object
still has any refs left. Checking the return value is also not
mandatory.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Per the FSF address could be changed from time to time, and GNU
recommends the following now: (http://www.gnu.org/licenses/gpl-howto.html)

  You should have received a copy of the GNU General Public License
  along with Foobar.  If not, see <http://www.gnu.org/licenses/>.

This patch removes the explicit FSF address, and uses above instead
(of course, with inserting 'Lesser' before 'General').

Except a bunch of files for security driver, all others are changed
automatically, the copyright for securify files are not complete,
that's why to do it manually:

  src/security/security_selinux.h
  src/security/security_driver.h
  src/security/security_selinux.c
  src/security/security_apparmor.h
  src/security/security_apparmor.c
  src/security/security_driver.c

This patch updates qemu driver to allow the client to choose the
vmcore's format: memory only or including device state.

When we added the default USB controller into domain XML, we efficiently
broke migration to older versions of libvirt that didn't support USB
controllers at all (0.9.4 and earlier) even for domains that don't use
anything that the older libvirt can't provide. We still want to present
the default USB controller in any XML seen by a user/app but we can
safely remove it from the domain XML used during migration. If we are
migrating to a new enough libvirt, it will add the controller XML back,
while older libvirt won't be confused with it although it will still
tell qemu to create the controller.

Similar approach can be used in the future whenever we find out we
always enabled some kind of device without properly advertising it in
domain XML.

Always use appropriate qemuDomain{,Def}Format wrapper since it may do
some additional magic based on the flags.

In case an API fails with "cannot acquire state change lock", searching
for the API that possibly forgot to end its job is not always easy.
Let's keep track of the job owner and print it out for easier
identification.

As reported by Daniel Berrangé, we have a huge performance regression
for virDomainGetInfo() due to the change which makes virDomainEndJob()
save the XML status file every time it is called. Previous to that
change, 2000 calls to virDomainGetInfo() took ~2.5 seconds. After that
change, 2000 calls to virDomainGetInfo() take 2 *minutes* 45 secs.

We made the change to be able to recover from libvirtd restart in the
middle of a job. However, only destroy and async jobs are taken care of.
Thus it makes more sense to only save domain state XML when these jobs
are started/stopped.

Destination daemon should not rely on the client or source daemon
(depending on the type of migration) to call Finish when migration
fails, because the client may crash before it can do so. The domain
prepared for incoming migration is set to be destroyed (and migration
job cleaned up) when connection with the client closes but this is not
enough. If the associated qemu process crashes after Prepare step and
the domain is cleaned up before the connection gets closed, autodestroy
is not called for the domain and migration jobs remains set. In case the
domain is defined on destination host (i.e., it is not completely
removed once destroyed) we keep the job set for ever. To fix this, we
register a cleanup callback which is responsible to clean migration-in
job when a domain dies anywhere between Prepare and Finish steps. Note
that we can't blindly clean any job when spotting EOF on monitor since
normally an API is running at that time.

Add support for registering cleanup callbacks to be run when a domain
transitions to shutoff state.

This reverts commit 61f2b6ba and most of
commit d8916dc8, which effectively
brings back commit ef1065cf written by
Jim Fehlig:

The qemu migration speed default is 32MiB/s as defined in migration.c

/* Migration speed throttling */
static int64_t max_throttle = (32 << 20);

There's no need to throttle migration when targeting a file, so set
migration speed to unlimited prior to migration, and restore to libvirt
default value after migration.

Default units is MB for migrate_set_speed monitor command, so
(INT64_MAX / (1024 * 1024)) is used for unlimited migration speed.

This was reverted because migration to file could not be canceled and
even monitored since qemu was not processing any monitor commands until
the migration finished. This is now different as we make sure the
file descriptor we pass to qemu is able to properly report EAGAIN.
Recent qemu changes might have helped as well.

I tested managedsave with this patch in and indeed, it is 10x faster
while I can still monitor its progress.

When host-model and host-passthrouh CPU modes were introduced, qemu
driver was properly modify to update guest CPU definition during
migration so that we use the right CPU at the destination. However,
similar treatment is needed for (managed)save and snapshots since they
need to save the exact CPU so that a domain can be properly restored.
To avoid repetition of such situation, all places that need live XML
share the code which generates it.

As a side effect, this patch fixes error reporting from
qemuDomainSnapshotWriteMetadata().

This patch fixes console corruption, that happens if two concurrent
sessions are opened for a single console on a domain. Result of this
corruption was that each of the console streams recieved just a part
of the data written to the pipe so every console rendered unusable.

New helper function for safe console handling is used to establish the
console stream connection. This function ensures that no other libvirt
client is using the console (with the ability to disconnect consoles of
libvirt clients) and that no UUCP style lockfile is placed on the PTY
device.

* src/qemu/qemu_domain.h
        - add data structure to domain's private data dealing with
          console connections
* src/qemu/qemu_domain.c:
        - allocate/free domain's console data structure
* src/qemu/qemu_driver.c
        - use the new helper function for console handling

There is now a standard QEMU guest agent that can be installed
and given a virtio serial channel

    <channel type='unix'>
      <source mode='bind' path='/var/lib/libvirt/qemu/f16x86_64.agent'/>
      <target type='virtio' name='org.qemu.guest_agent.0'/>
    </channel>

The protocol that runs over the guest agent is JSON based and
very similar to the JSON monitor. We can't use exactly the same
code because there are some odd differences in the way messages
and errors are structured. The qemu_agent.c file is based on
a combination and simplification of qemu_monitor.c and
qemu_monitor_json.c

* src/qemu/qemu_agent.c, src/qemu/qemu_agent.h: Support for
  talking to the agent for shutdown
* src/qemu/qemu_domain.c, src/qemu/qemu_domain.h: Add thread
  helpers for talking to the agent
* src/qemu/qemu_process.c: Connect to agent whenever starting
  a guest
* src/qemu/qemu_monitor_json.c: Make variable static

In commit 6f84e110 I mistakenly set default migration speed to
33554432 Mb!  The units of migMaxBandwidth is Mb, with conversion
handled in qemuMonitor{JSON,Text}SetMigrationSpeed().

Also, remove definition of QEMU_DOMAIN_FILE_MIG_BANDWIDTH_MAX since
it is no longer used after reverting commit ef1065cf.

When destroying a domain qemuDomainDestroy kills its qemu process and
starts a new job, which means it unlocks the domain object and locks it
again after some time. Although the object is usually unlocked for a
pretty short time, chances are another thread processing an EOF event on
qemu monitor is able to lock the object first and does all the cleanup
by itself. This leads to wrong shutoff reason and lifecycle event detail
and virDomainDestroy API incorrectly reporting failure to destroy an
inactive domain.

Reported by Charlie Smurthwaite.

This patch implements on_missing feature in qemu driver.
Upon qemu startup process an accessibility of CDROMs
and floppy disks is checked. The source might get dropped
if unavailable and on_missing is set accordingly.
No event is emit thought. Look for follow up patch.

Destination libvirtd remembers the original name in the prepare phase
and clears it in the finish phase. The original name is used when
comparing domain name in migration cookie.

Currently, qemuDomainGetXMLDesc and qemudDomainGetInfo check for
outstanding synchronous job before (eventual) monitor entering.
However, there can be already async job set, e.g. migration.

Thus, when libvirtd is restarted, it will know if a domain is supposed
to be killed or reset when it shuts down.

This patch is mostly code motion - moving some functions out
of qemu_driver and into qemu_domain so they can be reused by
multiple qemu_* files (since qemu_driver.h must not grow).
It also adds a new helper function, qemuDomainRemoveInactive,
which will be used in the next patch.

* src/qemu/qemu_domain.h (qemuFindQemuImgBinary)
(qemuDomainSnapshotWriteMetadata, qemuDomainSnapshotForEachQcow2)
(qemuDomainSnapshotDiscard, qemuDomainSnapshotDiscardAll)
(qemuDomainRemoveInactive): New prototypes.
(struct qemu_snap_remove): New struct.
* src/qemu/qemu_domain.c (qemuDomainRemoveInactive)
(qemuDomainSnapshotDiscardAllMetadata): New functions.
(qemuFindQemuImgBinary, qemuDomainSnapshotWriteMetadata)
(qemuDomainSnapshotForEachQcow2, qemuDomainSnapshotDiscard)
(qemuDomainSnapshotDiscardAll): Move here...
* src/qemu/qemu_driver.c (qemuFindQemuImgBinary)
(qemuDomainSnapshotWriteMetadata, qemuDomainSnapshotForEachQcow2)
(qemuDomainSnapshotDiscard, qemuDomainSnapshotDiscardAll): ...from
here.
(qemuDomainUndefineFlags): Update caller.
* src/conf/domain_conf.c (virDomainRemoveInactive): Doc fixes.

gcc warns when building libvirt 0.9.5 on a 32-bit machine:

qemu/qemu_migration.c: In function 'qemuMigrationToFile':
qemu/qemu_migration.c:2727:38: error: large integer implicitly truncated to unsigned type [-Woverflow]

* src/qemu/qemu_domain.h (QEMU_DOMAIN_FILE_MIG_BANDWIDTH_MAX): Cap
to long when building for 32-bit platform.

The maximum bandwidth that can be consumed when migrating a domain
is better classified as an operational vs configuration parameter of
the dommain.  As such, store this parameter in qemuDomainObjPrivate
structure.