Fix memory leak in QEMU QMP capabilities initialization

The qemuCapsInitQMP method never frees the QEMU 'package'
version string.
Log warning if storage magic matches, but version does not

To help us detect when new storage file versions come into
existance log a warning if the storage file magic matches,
but the version does not

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add lots of debugging to storage file probing code

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Fix probing of QED file format

The QED file format is non-versioned, so although the magic
value matched, libvirt rejected it due to lack of a version
number to compare against. We need to distinguish this case
by allowing a value of '-2' to indicate a non-versioned file
where only the magic is required to match

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Support network boot for HVM guests in libxl

The libxl driver ignored boot devices in the domain config,
preventing PXE booting HVM domains.  This patch accounts for
user-specified boot devices when building the libxl domain
configuration.
Fix error reporting when fetching SCSI/LVM keys

The current  virStorageFileGet{LVM,SCSI}Key methods return
the key as the return value. Unfortunately it is desirable
for "NULL" to be a valid return value, as well as an error
indicator. Thus the returned key must instead be provided
as an out-parameter.

When we invoke lvs or scsi_id to extract ID for block devices,
we don't want virCommandWait logging errors messages. Thus we
must explicitly check 'status != 0', rather than letting
virCommandWait do it.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Refactor creation of lock manager plugins

Refactor virLockManagerPluginNew() so that the caller does
not need to pass in the config file path itself - just the
config directory and driver name.

Fix QEMU to actually pass in a config file when creating the
default lock manager plugin, rather than NULL.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Introduce basic infrastructure for virtlockd daemon

The virtlockd daemon will maintain locks on behalf of libvirtd.
There are two reasons for it to be separate

 - Avoid risk of other libvirtd threads accidentally
   releasing fcntl() locks by opening + closing a file
   that is locked
 - Ensure locks can be preserved across libvirtd restarts.
   virtlockd will need to be able to re-exec itself while
   maintaining locks. This is simpler to achieve if its
   sole job is maintaining locks

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Define a wire protocol for talking to the virtlockd daemon

The virtlockd daemon will be responsible for managing locks
on virtual machines. Communication will be via the standard
RPC infrastructure. This provides the XDR protocol definition

* src/locking/lock_protocol.x: Wire protocol for virtlockd
* src/Makefile.am: Include lock_protocol.[ch] in virtlockd

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Implement dispatch functions for lock protocol in virtlockd

Introduce a lock_daemon_dispatch.c file which implements the
server side dispatcher the RPC APIs previously defined in the
lock protocol.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Enable systemd socket activation with virtlockd

This enhancement virtlockd so that it can receive a pre-opened
UNIX domain socket from systemd at launch time, and adds the
systemd service/socket unit files

* daemon/libvirtd.service.in: Require virtlockd to be running
* libvirt.spec.in: Add virtlockd systemd files
* src/Makefile.am: Install systemd files
* src/locking/lock_daemon.c: Support socket activation
* src/locking/virtlockd.service.in, src/locking/virtlockd.socket.in:
  systemd unit files
* src/rpc/virnetserverservice.c, src/rpc/virnetserverservice.h:
  Add virNetServerServiceNewFD() method
* src/rpc/virnetsocket.c, src/rpc/virnetsocket.h: Add virNetSocketNewListenFD
  method

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add support for re-exec() of virtlockd upon SIGUSR1

The virtlockd daemon maintains file locks on behalf of libvirtd
and any VMs it is running. These file locks must be held for as
long as any VM is running. If virtlockd itself ever quits, then
it is expected that a node would be fenced/rebooted. Thus to
allow for software upgrads on live systemd, virtlockd needs the
ability to re-exec() itself.

Upon receipt of SIGUSR1, virtlockd will save its current live
state out to a file /var/run/virtlockd-restart-exec.json
It then re-exec()'s itself with exactly the same argv as it
originally had, and loads the state file, reconstructing any
objects as appropriate.

The state file contains information about all locks held and
all network services and clients currently active. An example
state document is

 {
    "server": {
        "min_workers": 1,
        "max_workers": 20,
        "priority_workers": 0,
        "max_clients": 20,
        "keepaliveInterval": 4294967295,
        "keepaliveCount": 0,
        "keepaliveRequired": false,
        "services": [
            {
                "auth": 0,
                "readonly": false,
                "nrequests_client_max": 1,
                "socks": [
                    {
                        "fd": 6,
                        "errfd": -1,
                        "pid": 0,
                        "isClient": false
                    }
                ]
            }
        ],
        "clients": [
            {
                "auth": 0,
                "readonly": false,
                "nrequests_max": 1,
                "sock": {
                    "fd": 9,
                    "errfd": -1,
                    "pid": 0,
                    "isClient": true
                },
                "privateData": {
                    "restricted": true,
                    "ownerPid": 1722,
                    "ownerId": 6,
                    "ownerName": "f18x86_64",
                    "ownerUUID": "97586ba9-df27-9459-c806-f016c8bbd224"
                }
            },
            {
                "auth": 0,
                "readonly": false,
                "nrequests_max": 1,
                "sock": {
                    "fd": 10,
                    "errfd": -1,
                    "pid": 0,
                    "isClient": true
                },
                "privateData": {
                    "restricted": true,
                    "ownerPid": 1784,
                    "ownerId": 7,
                    "ownerName": "f16x86_64",
                    "ownerUUID": "7b8e5e42-b875-61e9-b981-91ad8fa46979"
                }
            }
        ]
    },
    "defaultLockspace": {
        "resources": [
            {
                "name": "/var/lib/libvirt/images/f16x86_64.raw",
                "path": "/var/lib/libvirt/images/f16x86_64.raw",
                "fd": 14,
                "lockHeld": true,
                "flags": 0,
                "owners": [
                    1784
                ]
            },
            {
                "name": "/var/lib/libvirt/images/shared.img",
                "path": "/var/lib/libvirt/images/shared.img",
                "fd": 12,
                "lockHeld": true,
                "flags": 1,
                "owners": [
                    1722,
                    1784
                ]
            },
            {
                "name": "/var/lib/libvirt/images/f18x86_64.img",
                "path": "/var/lib/libvirt/images/f18x86_64.img",
                "fd": 11,
                "lockHeld": true,
                "flags": 0,
                "owners": [
                    1722
                ]
            }
        ]
    },
    "lockspaces": [

    ],
    "magic": "30199"
 }

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a virtlockd client as a lock driver impl

This adds a 'lockd' lock driver which is just a client which
talks to the lockd daemon to perform all locking. This will
be the default lock driver for any hypervisor which needs one.

* src/Makefile.am: Add lockd.so plugin
* src/locking/lock_driver_lockd.c: Lockd driver impl

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add ability to maintain disk leases indirectly

The default lockd driver behavour is to acquire leases
directly on the disk files. This introduces an alternative
mode, where leases are acquire indirectly on a file that
is based on a SHA256 hash of the disk filename.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add support for locking based on LVM volume uuid
Add support for locking based on SCSI volume ID
api: Add API to tunnel a guest channel via stream

This patch adds a new API, virDomainOpenChannel, that uses streams to
connect to a virtio channel on a guest.  This creates a secure
communication channel between a guest and a libvirt client.

This behaves the same as virDomainOpenConsole, except on channels
instead of console/serial/parallel devices.
conf: Rename virconsole.* to virchrdev.*

This is just code motion, in preparation to rename identifiers to be
less console-specific.
conf: Rename console-specific identifiers to be more generic

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".
conf: Add unix socket support to virChrdevOpen

This also changes the function signature to take a
virDomainChrSourceDefPtr instead of just a path, since it needs to
differentiate behavior based on source->type.