Add <features> and <compat> elements to volume target XML.

<compat> is a string which for qcow2 represents the QEMU version
it should be compatible with. Valid values are 0.10 and 1.1.
1.1 is implicit if the <features> element is present, otherwise
qemu-img default is used. 0.10 can be specified to explicitly
create older images after the qemu-img default changes.

<features> contains optional features, so far
<lazy_refcounts/> is available, which enables caching of reference
counters, improving performance for snapshots.

Detect qcow2 images with version 3 in the image header as
VIR_STORAGE_FILE_QCOW2.

These images have a feature bitfield, with just one feature supported
so far: lazy_refcounts.

The header length changed too, moving the location of the backing
format name.

XML:
<features>
  <hyperv>
    <vapic state='on'/>
    <spinlocks state='on' retries='4096'/>
  </hyperv>
</features>

results in the following QEMU command line:
qemu -cpu <cpu_model>,hv_vapic,hv_spinlocks=0x1000

https://bugzilla.redhat.com/show_bug.cgi?id=784836

Add new CPU features for HyperV:
vapic for virtual APIC support
spinlocks for setting spinlock support

<features>
  <hyperv>
    <vapic state='on'/>
    <spinlocks state='on' retries='4096'/>
  </hyperv>
</features>

https://bugzilla.redhat.com/show_bug.cgi?id=784836

Implementation uses SIOCIFCREATE2 and SIOCIFDESTROY ioctls.
Also, drop static virNetDevSetupControl() as we have
public one avialable now.

As the RNG schema for disk auth secret implies, it requires either
"uuid" or "usage":

  <define name='diskAuthSecret'>
    <element name='secret'>
      <attribute name='type'>
        <choice>
          <value>ceph</value>
          <value>iscsi</value>
        </choice>
      </attribute>
      <choice>
        <attribute name='uuid'>
          <ref name="UUID"/>
        </attribute>
        <attribute name='usage'>
          <ref name='genericName'/>
        </attribute>
      </choice>
    </element>
  </define>

Commit 752596b5 broke the build with -Werror

qemu/qemu_hotplug.c: In function 'qemuDomainChangeGraphics':
qemu/qemu_hotplug.c:1980:39: error: declaration of 'listen' shadows a
  global declaration [-Werror=shadow]

Fix with s/listen/newlisten/

This fixes the problem reported in:

   https://bugzilla.redhat.com/show_bug.cgi?id=972690

When checking for a collision of a new libvirt network's subnet with
any existing routes, we read all of /proc/net/route into memory, then
parse all the entries. The function that we use to read this file
requires a "maximum length" parameter, which had previously been set
to 64*1024. As each line in /proc/net/route is 128 bytes, this would
allow for a maximum of 512 entries in the routing table.

This patch increases that number to 128 * 100000, which allows for
100,000 routing table entries. This means that it's possible that 12MB
would be allocated, but that would only happen if there really were
100,000 route table entries on the system, it's only held for a very
short time.

Since there is no method of specifying and unlimited max (and that
would create a potential denial of service anyway) hopefully this
limit is large enough to accomodate everyone.

Signed-off-by: NMarek Marczykowski-Górecki <marmarek@invisiblethingslab.com>

Currently, we have a bug when updating a graphics device. A graphics device can
have a listen address set. This address is either defined by user (in which case
it's type is VIR_DOMAIN_GRAPHICS_LISTEN_TYPE_ADDRESS) or it can be inherited
from a network (in which case it's type is
VIR_DOMAIN_GRAPHICS_LISTEN_TYPE_NETWORK). However, in both cases we have a
listen address to process (e.g. during migration, as I've tried to fix in
7f15ebc7).
Later, when a user tries to update the graphics device (e.g. set a password),
we check if listen addresses match the original as qemu doesn't know how to
change listen address yet. Hence, users are required to not change the listen
address. The implementation then just dumps listen addresses and compare them.
Previously, while dumping the listen addresses, NULL was returned for NETWORK.
After my patch, this is no longer true, and we get a listen address for olddev
even if it is a type of NETWORK. So we have a real string on one side, the NULL
from user's XML on the other side and hence we think user wants to change the
listen address and we refuse it.

Therefore, we must take the type of listen address into account as well.

Do not leave uninitialized variables, not all parameters are set in
libxlMake*.
Signed-off-by: NMarek Marczykowski-Górecki <marmarek@invisiblethingslab.com>

libxl uses some xenstore entries for hints in memory management
(especially when starting new domain). This includes dom0 memory limit
and Xen free memory margin, based on current system state. Entries are
created at first function usage, so force such call at daemon startup,
which most likely will be before any domain startup.
Also prevent automatic memory management if dom0_mem= option passed to
xen hypervisor - it is known to be incompatible with autoballoon.
Signed-off-by: NMarek Marczykowski-Górecki <marmarek@invisiblethingslab.com>

As a consequence of the cgroup layout changes from commit 'cfed9ad4', the
lxcDomainGetSchedulerParameters[Flags]()' and lxcGetSchedulerType() APIs
failed to return data for a non running domain.  This can be seen through
a 'virsh schedinfo <domain>' command which returns:

Scheduler      : Unknown
error: Requested operation is not valid: cgroup CPU controller is not mounted

Prior to that change a non running domain would return:

Scheduler      : posix
cpu_shares     : 0
vcpu_period    : 0
vcpu_quota     : 0
emulator_period: 0
emulator_quota : 0

This patch will restore the capability to return configuration only data
for a non running domain regardless of whether cgroups are available.

As a consequence of the cgroup layout changes from commit '632f78ca', the
qemuDomainGetSchedulerParameters[Flags]()' and qemuGetSchedulerType() APIs
failed to return data for a non running domain.  This can be seen through
a 'virsh schedinfo <domain>' command which returns:

Scheduler      : Unknown
error: Requested operation is not valid: cgroup CPU controller is not mounted

Prior to that change a non running domain would return:

Scheduler      : posix
cpu_shares     : 0
vcpu_period    : 0
vcpu_quota     : 0
emulator_period: 0
emulator_quota : 0

This patch will restore the capability to return configuration only data
for a non running domain regardless of whether cgroups are available.

Just to reduce the indentation levels. Remove the unneeded
NULL check for disk->file, as virBufferEscapeString doesn't
print anything with NULL arguments.

Split out option string generation to make adding new options easier
and simplify the code.

We don't care whether the trim was succesful or not anywhere
except the tests.

Switch it to void and set the buffer error on wrong usage.

This flag is meant for errors happening on the source of the migration
and isn't used on the destination. To allow better migration
compatibility, don't propagate it to the destination.

Paolo Bonzini pointed out that it's actually possible to migrate a qemu
instance that was paused due to I/O error and it will be able to work on
the destination if the storage is accessible.

This patch introduces flag VIR_MIGRATE_ABORT_ON_ERROR that cancels the
migration in case an I/O error happens while it's being performed and
allows migration without this flag. This flag can be possibly used for
other error reasons that may be introduced in the future.

Currently, we wait for SPICE to migrate in the very same loop where we
wait for qemu to migrate. This has a disadvantage of slowing seamless
migration down. One one hand, we should not kill the domain until all
SPICE data has been migrated.  On the other hand, there is no need to
wait in the very same loop and hence slowing down 'cont' on the
destination. For instance, if users are watching a movie, they can
experience the movie to be stopped for a couple of seconds, as
processors are not running nor on src nor on dst as libvirt waits for
SPICE to migrate. We should move the waiting phase to migration CONFIRM
phase.

F20/rawhide has support for this.

From: Peter Robinson <pbrobinson@gmail.com>

Document for nodedev-list is also updated.

The xml outputed by HAL backend for scsi generic device:

<device>
  <name>pci_8086_2922_scsi_host_scsi_device_lun0_scsi_generic</name>
  <path>/sys/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/scsi_generic/sg0</path>
  <parent>pci_8086_2922_scsi_host_scsi_device_lun0</parent>
  <capability type='scsi_generic'>
    <char>/dev/sg0</char>
  </capability>
</device>

Since scsi generic device doesn't have DEVTYPE property set, the
only way to know if it's a  scsi generic device or not is to read
the "SUBSYSTEM" property.

The XML of the scsi generic device will be like:

<device>
  <name>scsi_generic_sg0</name>
  <path>/sys/devices/pci0000:00/0000:00:1f.2/ata1/host0/target0:0:0/0:0:0:0/scsi_generic/sg0</path>
  <parent>scsi_0_0_0_0</parent>
  <capability type='scsi_generic'>
    <char>/dev/sg0</char>
  </capability>
</device>

When qemu >= 1.20, it is safe to use -device for primary video
device as described in 4c993d8a.
So, we are missing the cap flag in QMP capabilities detection, this
flag can be initialized safely in virQEMUCapsInitQMPBasic.

Checking if the "devtype" is NULL along with each "if" statements
is bad. It wastes the performance, and also not good for reading.
And also when the "devtype" is NULL, the logic is also not clear.

This reorgnizes the logic of with "if...else" and a bunch of "else if".

Other changes:
   * Change the function style.
   * Remove the useless debug statement.
   * Get rid of the goto
   * New helper udevDeviceHasProperty to simplify the logic for checking
     if a property is existing for the device.
   * Add comment to clarify "PCI devices don't set the DEVTYPE property"
   * s/sysfs path/sysfs name/, as udev_device_get_sysname returns the
     name instead of the full path. E.g. "sg0"
   * Refactor the comment for setting VIR_NODE_DEV_CAP_NET cap type
     a bit.

The name format is constructed by libvirt, it's not that clear to
get what the device's sysfs path should be. This exposes the device's
sysfs path by a new tag <path>.

Since the sysfspath is filled during enumerating the devices by
either udev or HAL. It's an output-only tag.

In the first if case, virGetUserEnt() isn't necessary so don't bother
calling it before determining we need it.

Implementation uses SIOCIFCREATE2 and SIOCIFDESTROY ioctls.

This method is useful not only in virnetdev.c.

Call virLogVMessage instead of virLogMessage, since libudev
called us with a va_list object, not a list of arguments.

Honor message priority and strip the trailing newline.

https://bugzilla.redhat.com/show_bug.cgi?id=969152

...fixes a trivial copy&paste error.
Signed-off-by: NRichard Weinberger <richard@nod.at>

The parsed path in the URI may be NULL resulting into:

  $ virsh -c qemu+ssh:// list
  Segmentation fault (core dumped)

Introduced by 22d81ceb