A QEMU guest can have upto VIR_DOMAIN_BOOT_LAST boot entries
defined. When building the QEMU arg, each entry takes a
single byte. This means the array must be declared to be
VIR_DOMAIN_BOOT_LAST+1 bytes in length to allow for the
trailing null

* src/qemu/qemu_conf.c: Fix off-by-1 boot arg array size

Previously QEMU enabled KQEMU by default and had -no-kqemu.
0.11.x switched to requiring -enable-kqemu. 0.12.x dropped
kqemu entirely. This patch adds support for -enable-kqemu
so 0.11.x works. It replaces a huge set of if() with a
switch() to make the code a bit more readable.

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Support
  -enable-kqemu

We already filled the PCI address structure when we checked whether it's
free or not, so let's just use the structure here instead of filling it
again.

  The balloon device is automatically added to qemu guests if supported,
but it may be useful to desactivate it. The simplest to not change the
existing behaviour is to allow
  <memballoon type="none"/>
as an extra option to desactivate it (it is automatically added if the
memballoon construct is missing for the domain).
The following simple patch just adds the extra option and does not
change the default behaviour but avoid creating a balloon device if
type="none" is used.

* docs/schemas/domain.rng: add the extra type attribute value
* src/conf/domain_conf.c src/conf/domain_conf.h: add the extra enum
  value
* src/qemu/qemu_conf.c: if enum is NONE, don't activate the device,
  i.e. don't pass the args to qemu/kvm

Fix the error checking to use the return value from brAddTap() instead
of checking the current errno value which might have been changed by
clean up calls inside of brAddTap().
Signed-off-by: NDoug Goldstein <cardoe@gentoo.org>

Added a more detailed error message when adding a tap devices fails and
the kernel is missing tun support.
Signed-off-by: NDoug Goldstein <cardoe@gentoo.org>

the followup on the boot=on problem, basically it's not needed to
specify it when booting out of IDE devices when using KVM
* src/qemu/qemu_conf.c: do not use boot=on for IDE devices
* tests/qemuxml2argvdata/qemuxml2argv*.args: this changes the output
  for 5 of the tests

Patch version revamped by Eric Blake <eblake@redhat.com> of Jiri
Denemark <jdenemar@redhat.com> original patch

When attaching a PCI device which doesn't explicitly set its PCI
address, libvirt allocates the address automatically. The problem is
that when checking which PCI address is unused, we only check for those
with slot number higher than the highest slot number ever used.

Thus attaching/detaching such device several times in a row (31 is the
theoretical limit, less then 30 tries are enough in practise) makes any
further device attachment fail. Furthermore, attaching a device with
predefined PCI address to 0:0:31 immediately forbids attachment of any
PCI device without explicit address.

This patch changes the logic so that we always check all PCI addresses
before we say there is no PCI address available.

Modifications from v1: revert back to remembering the last slot
reserved, but allow wraparound to not be limited by the end.
In this way, slots are still assigned in the same order as
before the patch, rather than filling in the gaps closest to
0 and risking making windows guests mad.

* src/qemu/qemu_conf.c: fix pci reservation code to do a round-robbin
  check of all available PCI splot availability before failing.

  Basically the 'boot=on' boot selection device is something present in
KVM but not in upstream QEmu, as a result if we boot a QEmu domain
without KVM acceleration we must disable boot=on ... even if the front
end kvm binary expose that capability in the help page.

* src/qemu/qemu_conf.c: in qemudBuildCommandLine if -no-kvm
  is passed, then deactivate QEMUD_CMD_FLAG_DRIVE_BOOT

ADD_ARG_LIT should only be used for literal arguments,
since it duplicates the memory.  Since virBufferContentAndReset
is already allocating memory, we should only use ADD_ARG.
Signed-off-by: NChris Lalancette <clalance@redhat.com>

Enable specifying a virtio console device with:

<console type='pty'>
  <target type='virtio'/>
</console>

All <console> devices now export a <target> type attribute. QEMU defaults
to 'serial', UML defaults to 'uml, xen can be either 'serial' or 'xen'
depending on fullvirt. Understandably there is lots of test fallout.

This will be used to differentiate between a serial vs. virtio console for
QEMU.
Signed-off-by: NCole Robinson <crobinso@redhat.com>

targetType only tracks the actual <target> format we are parsing. Currently
we only fill abide this value for channel devices.
Signed-off-by: NCole Robinson <crobinso@redhat.com>

There is actually a difference between the character device type (serial,
parallel, channel, ...) and the target type (virtio, guestfwd). Currently
they are awkwardly conflated.

Start to pull them apart by renaming targetType -> deviceType. This is
an entirely mechanical change.
Signed-off-by: NCole Robinson <crobinso@redhat.com>

QEMU has had two different syntax for disk cache options

 Old: on|off
 New: writeback|writethrough|none

QEMU recently added another 'unsafe' option which broke the
libvirt check. We can avoid this & future breakage, if we
do a negative check for the old syntax, instead of a positive
check for the new syntax

* src/qemu/qemu_conf.c: Invert cache option check

Add a new element to the <os> block:

  <bootmenu enable="yes|no"/>

Which maps to -boot,menu=on|off on the QEMU command line.

I decided to use an explicit 'enable' attribute rather than just make the
bootmenu element boolean. This allows us to treat lack of a bootmenu element
as 'use hypervisor default'.

Throw an explicit error if multiple graphics devices are specified, or
an unsupported type is specified (rdp).

Now that we have the ability to specify arbitrary qemu
command-line parameters in the XML, use it to handle unknown
command-line parameters when doing a native-to-xml conversion.

Changes since v1:
 - Rename num_extra to num_args
 - Fix up a memory leak on an error path

Changes since v2:
 - Add a VIR_WARN when adding the argument via qemu:arg

Changes since v3:
 - None
Signed-off-by: NChris Lalancette <clalance@redhat.com>

Implement the qemu hooks for XML namespace data.  This
allows us to specify a qemu XML namespace, and then
specify:

<qemu:commandline>
 <qemu:arg value='arg'/>
 <qemu:env name='name' value='value'/>
</qemu:commandline>

In the domain XML.

Changes since v1:
 - Change the <qemu:arg>arg</qemu:arg> XML to <qemu:arg value='arg'/> XML
 - Fix up some memory leaks in qemuDomainDefNamespaceParse
 - Rename num_extra and extra to num_args and args, respectively
 - Fixed up some error messages
 - Make sure to escape user-provided data in qemuDomainDefNamespaceFormatXML

Changes since v2:
 - Add checking to ensure environment variable names are valid
 - Invert the logic in qemuDomainDefNamespaceFormatXML to return early

Changes since v3:
 - Change strspn() to c_isalpha() check of first letter of environment variable
Signed-off-by: NChris Lalancette <clalance@redhat.com>

A Linux software bridge will assume the MAC address of the enslaved
interface with the numerically lowest MAC addr. When the bridge
changes MAC address there is a period of network blackout, so a
change should be avoided. The kernel gives TAP devices a completely
random MAC address. Occassionally the random TAP device MAC is lower
than that of the physical interface (eth0, eth1etc) that is enslaved,
causing the bridge to change its MAC.

This change sets an explicit MAC address for all TAP devices created
using the configured MAC from the XML, but with the high byte set
to 0xFE. This should ensure TAP device MACs are higher than any
physical interface MAC.

* src/qemu/qemu_conf.c, src/uml/uml_conf.c: Pass in a MAC addr
  for the TAP device with high byte set to 0xFE
* src/util/bridge.c, src/util/bridge.h: Set a MAC when creating
  the TAP device to override random MAC

The PCI slot 1 must be reserved at all times, since PIIX3 is
always present, even if no IDE device is in use for guest disks

* src/qemu/qemu_conf.c: Always reserve slot 1 for PIIX3

To try and ensure that people upgrading from old QEMU get guests
with the same PCI device ordering, change the way we assign addrs
to match QEMU's default order. This should make Windows less
annoyed.

* src/qemu/qemu_conf.c: Follow QEMU's default PCI ordering
  logic when assigning addresses
* tests/*.args: Update for changed PCI addresses

To allow compatibility with older QEMU PCI device slot assignment
it is necessary to explicitly track the balloon device in the
XML. This introduces a new device

   <memballoon model='virtio|xen'/>

It can also have a PCI address, auto-assigned if necessary.

The memballoon will be automatically added to all Xen and QEMU
guests by default.

* docs/schemas/domain.rng: Add <memballoon> element
* src/conf/domain_conf.c, src/conf/domain_conf.h: parsing
  and formatting for memballoon device. Always add a memory
  balloon device to Xen/QEMU if none exists in XML
* src/libvirt_private.syms: Export memballoon model APIs
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Honour the
  PCI device address in memory balloon device
* tests/*: Update to test new functionality

The first VGA and IDE devices need to have fixed PCI address
reservations. Currently this is handled inline with the other
non-primary VGA/IDE devices. The fixed virtio balloon device
at slot 3, ensures auto-assignment skips the slots 1/2. The
virtio address will shortly become configurable though. This
means the reservation of fixed slots needs to be done upfront
to ensure that they don't get re-used for other devices.

This is more or less reverting the previous changeset:

  commit 83acdeaf
  Author: Daniel P. Berrange <berrange@redhat.com>
  Date:   Wed Feb 3 16:11:29 2010 +0000

  Fix restore of QEMU guests with PCI device reservation

The difference is that this time, instead of unconditionally
reserving the address, we only reserve the address if it was
initially type=none. Addresses of type=pci were handled
earlier in process by qemuDomainPCIAddressSetCreate(). This
ensures restore step doesn't have problems

* src/qemu/qemu_conf.c: Reserve first VGA + IDE address
  upfront

The VIR_ERR_NO_SUPPORT refers to an API which is not implemented.
There is a separate VIR_ERR_CONFIG_UNSUPPORTED for XML config
options that are not available with the current hypervisor.

* src/qemu/qemu_conf.c, src/qemu/qemu_driver.c: Remove
  many VIR_ERR_NO_SUPPORT replace with VIR_ERR_CONFIG_UNSUPPORTED

Disk format probing is now disabled by default. A new config
option in /etc/qemu/qemu.conf will re-enable it for existing
deployments where this causes trouble

In case qemu supports -nodefconfig, libvirt adds uses it when launching
new guests. Since this option may affect CPU models supported by qemu,
we need to use it when probing for available models.

Log some info if we can't find a config file. Make parse failures
fatal, and actually raise an error message.

We previously assumed that if the -device option existed in qemu, that
-nodefconfig would also exist. It turns out that isn't the case, as
demonstrated by qemu-kvm-0.12.3 in Fedora 13.

*/src/qemu/qemu_conf.[hc] - add a new QEMUD_CMD_FLAG, set it via the
                            help output, and check it before adding
                            -nodefconfig to the qemu commandline.

The domain XML parsing code autogenerates disk address and
controller elements when they are not explicitly specified.
The code assumes a narrow SCSI bus (7 units per bus). ESX
uses a wide SCSI bus (16 units per bus).

This is a step towards controller support for the ESX driver.

We already use the '-nodefaults' command line arg with QEMU to stop
it adding any default devices to guests. Unfortunately, QEMU will
load global config files from /etc/qemu that may also add default
devices. These aren't blocked by '-nodefaults', so we need to also
add the '-nodefconfig' arg to prevent that.

Unfortunately these global config files are also used to define
custom CPU models. So in blocking global hardware device addition
we also block definitions of new CPU models. Libvirt doesn't know
about these custom CPU models though, so it would never make use
of them anyway. Thus blocking them via -nodefconfig isn't a show
stopping problem. We would need to expand libvirt's own CPU model
XML database to support these instead.

* src/qemu/qemu_conf.c: Add '-nodefconfig' if available
* tests/qemuxml2argvdata/: Add '-nodefconfig' to all data files which
  have '-nodefaults' present

Following Daniel Berrange's multiple helpful suggestions for improving
this patch and introducing another driver interface, I now wrote the
below patch where the nwfilter driver registers the functions to
instantiate and teardown the nwfilters with a function in
conf/domain_nwfilter.c called virDomainConfNWFilterRegister. Previous
helper functions that were called from qemu_driver.c and qemu_conf.c
were move into conf/domain_nwfilter.h with slight renaming done for
consistency. Those functions now call the function expored by
domain_nwfilter.c, which in turn call the functions of the new driver
interface, if available.

To ensure that the device addressing scheme is stable across
hotplug/unplug, all virtio serial channels needs to have an
associated port number in their address. This is then specified
to QEMU using the nr=NNN parameter

* src/conf/domain_conf.c, src/conf/domain_conf.h: Parsing
  for port number in vioserial address types.
* src/qemu/qemu_conf.c: Set 'nr=NNN' parameter with virtio
  serial port number
* tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.args,
  tests/qemuxml2argvdata/qemuxml2argv-channel-virtio.xml: Expand
  data set to ensure coverage of port addressing

This patch that adds support for configuring 802.1Qbg and 802.1Qbh
switches. The 802.1Qbh part has been successfully tested with real
hardware. The 802.1Qbg part has only been tested with a (dummy)
server that 'behaves' similarly to how we expect lldpad to 'behave'.

The following changes were made during the development of this patch:

 - Merging Scott's v13-pre1 patch
 - Fixing endptr related bug while using virStrToLong_ui() pointed out
   by Jim Meyering
 - Addressing Jim Meyering's comments to v11
 - requiring mac address to the vpDisassociateProfileId() function to
   pass it further to the 802.1Qbg disassociate part (802.1Qbh untouched)
 - determining pid of lldpad daemon by reading it from /var/run/libvirt.pid
   (hardcode as is hardcode alson in lldpad sources)
 - merging netlink send code for kernel target and user space target
   (lldpad) using one function nlComm() to send the messages
 - adding a select() after the sending and before the reading of the
   netlink response in case lldpad doesn't respond and so we don't hang
 - when reading the port status, in case of 802.1Qbg, no status may be
   received while things are 'in progress' and only at the end a status
   will be there.
 - when reading the port status, use the given instanceId and vf to pick
   the right IFLA_VF_PORT among those nested under IFLA_VF_PORTS.
 - never sending nor parsing IFLA_PORT_SELF type of messages in the
   802.1Qbg case
 - iterating over the elements in a IFLA_VF_PORTS to pick the right
   IFLA_VF_PORT by either IFLA_PORT_PROFILE and given profileId
   (802.1Qbh) or IFLA_PORT_INSTANCE_UUID and given instanceId (802.1Qbg)
   and reading the current status in IFLA_PORT_RESPONSE.
 - recycling a previous patch that adds functionality to interface.c to
   - get the vlan identifier on an interface
   - get the flags of an interface and some convenience function to
     check whether an interface is 'up' or not (not currently used here)
 - adding function to determine the root physical interface of an
   interface. For example if a macvtap is linked to eth0.100, it will
   find eth0. Also adding a function that finds the vlan on the 'way to
   the root physical interface'
 - conveying the root physical interface name and index in case of 802.1Qbg
 - conveying mac address of macvlan device and vlan identifier in
   IFLA_VFINFO_LIST[ IFLA_VF_INFO[ IFLA_VF_MAC(mac), IFLA_VF_VLAN(vlan) ] ]
   to (future) lldpad via netlink
  - To enable build with --without-macvtap rename the
    [dis|]associatePortProfileId functions, prepend 'vp' before their
    name and make them non-static functions.
  - Renaming variable multicast to nltarget_kernel and inverting
    the logic
  - Addressing Jim Meyering's comments; this also touches existing
    code for example for correcting indentation of break statements or
    simplification of switch statements.
  - Renamed occurrencvirVirtualPortProfileDef to virVirtualPortProfileParamses
  - 802.1Qbg part prepared for sending a RTM_SETLINK and getting
    processing status back plus a subsequent RTM_GETLINK to
    get IFLA_PORT_RESPONSE.
    Note: This interface for 802.1Qbg may still change
  - [David Allan] move getPhysfn inside IFLA_VF_PORT_MAX to avoid
compiler
    warning when latest if_link.h isn't available
  - move from Stefan's 802.1Qb{g|h} XML v8 to v9
  - move hostuuid and vf index calcs to inside doPortProfileOp8021Qbh
  - remove debug fprintfs
  - use virGetHostUUID (thanks Stefan!)
  - fix compile issue when latest if_link.h isn't available
  - change poll timeout to 10s, at 1/8 intervals
     - if polling times out, log msg and return -ETIMEDOUT
  - Add Stefan's code for getPortProfileStatus
  - Poll for up to 2 secs for port-profile status, at 1/8 sec intervals:
     - if status indicates error, abort openMacvtapTap
     - if status indicates success, exit polling
     - if status is "in-progress" after 2 secs of polling, exit
       polling loop silently, without error

My patch finishes out the 802.1Qbh parts, which Stefan had mostly complete.
I've tested using the recent kernel updates for VF_PORT netlink msgs and
enic for Cisco's 10G Ethernet NIC.  I tested many VMs, each with several
direct interfaces, each configured with a port-profile per the XML.  VM-to-VM,
and VM-to-external work as expected.  VM-to-VM on same host (using same NIC)
works same as VM-to-VM where VMs are on diff hosts.  I'm able to change
settings on the port-profile while the VM is running to change the virtual
port behaviour.  For example, adjusting a QoS setting like rate limit.  All
VMs with interfaces using that port-profile immediatly see the effect of the
change to the port-profile.

I don't have a SR-IOV device to test so source dev is a non-SR-IOV device,
but most of the code paths include support for specifing the source dev and
VF index.  We'll need to complete this by discovering the PF given the VF
linkdev.  Once we have the PF, we'll also have the VF index.  All this info-
mation is available from sysfs.

Currently there is no way to opt out of libvirt dropping POSIX
capabilities for qemu. This at least is a useful debugging tool, but
is also wanted by users (and distributors):

https://bugzilla.redhat.com/show_bug.cgi?id=559154
https://bugzilla.redhat.com/show_bug.cgi?id=573850

v2: Clarify qemu.conf comment, warn about security implications

v3: Add .aug changes

Since the macvtap device needs active tear-down and the teardown logic
is based on the interface name, it can happen that if for example 1 out
of 3 interfaces was successfully created, that during the failure path
the macvtap's target device name is used to tear down an interface that
is doesn't own (owned by another VM).

So, in this patch, the target interface name is reset so that there is
no target interface name and the interface name is always cleared after
a tear down.

This allows libvirt to open the PCI device sysfs config file prior
to dropping privileges so qemu can access the full config space.
Without this, a de-privileged qemu can only access the first 64
bytes of config space.

* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Detect support
  for pci-assign.configfd option. Use this option when formatting
  PCI device string if possible
* src/qemu/qemu_driver.c: Pre-open PCI sysfs config file and pass
  to QEMU

This patch parses the following two XML descriptions, one for
802.1Qbg and one for 802.1Qbh, and stores the data internally.
The actual triggering of the switch setup protocol has not been
implemented here but the relevant code to do that should go into
the functions associatePortProfileId() and disassociatePortProfileId().

   <interface type='direct'>
      <source dev='eth0.100' mode='vepa'/>
      <model type='virtio'/>
      <virtualport type='802.1Qbg'>
        <parameters managerid='12' typeid='0x123456' typeidversion='1'
         instanceid='fa9b7fff-b0a0-4893-8e0e-beef4ff18f8f'/>
      </virtualport>
      <filterref filter='clean-traffic'/>
    </interface>

    <interface type='direct'>
      <source dev='eth0.100' mode='vepa'/>
      <model type='virtio'/>
      <virtualport type='802.1Qbh'>
        <parameters profileid='my_profile'/>
      </virtualport>
    </interface>

I'd suggest to use this patch as a base for triggering the setup
protocol with the 802.1Qb{g|h} switch.

Several rounds of changes were made to this patch. The
following is a list of these changes.
- Renamed structure virVirtualPortProfileDef to virVirtualPortProfileParams
  as per Daniel Berrange's request
- Addressing Daniel Berrange's comments:
 - removing macvtap.h's dependency on domain_conf.h by
   moving the virVirtualPortProfileDef structure into macvtap.h
   and not passing virtDomainNetDefPtr to any functions in
   macvtap.c
- Addressed most of Chris Wright's comments:
  - indicating error in case virtualport XML node cannot be parsed
    properly
  - parsing hex and decimal numbers using virStrToLong_ui() with
    parameter '0' for base
  - tgifname (target interface name) variable wasn't necessary
    to pass to openMacvtapTap function anymore
- assigning the virtual port data structure to the virDomainNetDef
  only if it was previously parsed
- make sure that the error code returned by openMacvtapTap() is a negative n
  in case the associatePortProfileId() function failed.
- renaming vsi in the XML to virtualport
- replace all occurrences of vsi in the source as well
- removing mode and MAC address parameters from the functions that
  will communicate with the hareware diretctly or indirectly
- moving the associate and disassociate functions to the end of the
  file for subsequent patches to easier make them generally available
  for export
- passing the macvtap interface name rather than the link device since
  this otherwise gives funny side effects when using netlink messages
  where IFLA_IFNAME and IFLA_ADDRESS are specified and the link dev
  all of a sudden gets the MAC address of the macvtap interface.
- Removing rc = -1 error indications in the case of 802.1Qbg|h setup in case
  we wanted to use hook scripts for the setup and so the setup doesn't fail
  here.
- if instance ID UUID is not supplied it will automatically be generated
  - adapted schema to make instance ID UUID optional
  - added test case
- parser and XML generator have been separated into their own
  functions so they can be re-used elsewhere (passthrough case
  for example)
- Adapted XML parser and generator support the above shown type
  (802.1Qbg, 802.1Qbh).
- Adapted schema to above XML
- Adapted test XML to above XML
- Passing through the VM's UUID which seems to be necessary for
  802.1Qbh -- sorry no host UUID
- adding virtual function ID to association function, in case it's
  necessary to use (for SR-IOV)