There has been some progress lately in enabling virtio-pci on
aarch64 guests; however, guest OS support is still spotty at best,
so most guests are going to be using virtio-mmio instead.

Currently, mach-virt guests are closely modeled after q35 guests,
and that includes always adding a dmi-to-pci-bridge that's just
impossible to get rid of. While that's acceptable (if suboptimal)
for q35, where you will always need some kind of PCI device anyway,
mach-virt guests should be allowed to avoid it.

Commit ff212622 changed the error message to be more
detailed about the failure at hand; however, while the new
error message claims that "bus must be <= index", the error
message is displayed if "idx <= addr->bus", ie. when bus
is larger than or *equal to* index.

Change the error message to report the correct constraint,
and format it in a way that mirrors the check exactly to
make it clearer to people reading the code. The new error
message reads "index must be larger than bus".

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1339900

IS_USB2_CONTROLLER() is useful in more places aside from just when
assigning PCI addresses in QEMU, and is checking for enum values that
are all defined in conf/domain_conf.h anyway, so define it there
instead.

Based on some digital archaeology performed by jtomko, it's been determined
that the persistentAddrs variable is no longer necessary...

The variable was added by:
commit 141dea6b
CommitDate: 2010-02-12 17:25:52 +0000
    Add persistence of PCI addresses to QEMU

Where it was set to 0 on domain startup if qemu did not support the
QEMUD_CMD_FLAG_DEVICE capability, to clear the addresses at shutdown,
because QEMU might make up different ones next time.

As of commit f5dd58a6
CommitDate: 2012-07-11 11:19:05 +0200
    qemu: Extended qemuDomainAssignAddresses to be callable from
    everywhere.

this was broken, when the persistentAddrs = 0 assignment was moved
inside qemuDomainAssignPCIAddresses and while it pretends to check
for !QEMU_CAPS_DEVICE, its parent qemuDomainAssignAddresses is only
called if QEMU_CAPS_DEVICE is present.

Since commit id '20a0fa8e' removed the QEMU_CAPS_DEVICE, Coverity notes
that it's no longer possible to have 'addrs' be NULL when checking for
a live domain since qemuDomainPCIAddressSetCreate would have jumped to
cleanup if addrs was NULL.

Rather than only assigning a PCI address when no address is given at
all, also do it when the config says that the address type is 'pci',
but it gives no address (virDeviceInfoPCIAddressWanted()).

There are also several places after parsing but prior to address
assignment where code previously expected that any info with address
type='pci' would have a *valid* PCI address, which isn't always the
case - now we check not only for type='pci', but also for a valid
address (virDeviceInfoPCIAddressPresent()).

The test case added in this patch was directly copied from Cole's patch titled:

    qemu: Wire up address type=pci auto_allocate

All qemu versions we support have QEMU_CAPS_DEVICE, so checking
for it is redundant. Remove the usage.

The code diff isn't clear, but all that code is just inindented
with no other change.

Test cases that hit qemuDomainAssignAddresses but don't have
infrastructure for specifying qemuCaps values see lots of
churn, since now PCI addresses are in the XML output.

Use it everywhere except for virQEMUCapsFillDomainFeatureGICCaps.

It was not indented correctly.

We do not need to propagate the exact return values
and the only possible ones are 0 and -1 anyway.

Remove the temporary variable and use the usual pattern:

if (f() < 0)
    return -1;

This function does not fail and it does not need to return anything.

We had both and the only difference was that the latter also included
information about multifunction setting.  The problem with that was that
we couldn't use functions made for only one of the structs (e.g.
parsing).  To consolidate those two structs, use the one in virpci.h,
include that in domain_conf.h and add the multifunction member in it.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

This error message was too specific, based on the incorrect assumption
that any error was cause by auto-added bridges:

  failed to create PCI bridge on bus 2: too many devices
  with fixed addresses

In practice you can't know if a bridge with an index <= the bus it's
connecting to was added automatically, or if it was a mistake in
explicit config, and the auto-add problem is going to be dealt with in
a different way in an upcoming patch. The new message is this:

  PCI Controller at index 1 (0x01) has "
  bus='0x02', but bus must be <= index

(note that index is given in both decimal and hex because it is
formatted as decimal in the XML, but bus is formatted as hex, and
displaying the hex value of index makes it easier to see the problem
when index > 9 (which will often be the case with PCIe, since most
controllers only have a single port, not 32 slots as with standard
PCI)).

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1004593

This is backed by the qemu device pxb-pcie, which will be available in
qemu 2.6.0.

As with pci-expander-bus (which uses qemu's pxb device), the busNr
attribute and <node> subelement of <target> are used to set the bus_nr
and numa_node options.

During post-parse we validate that the domain's machinetype is
q35-based (since the device shows up for 440fx-based machinetypes, but
is unusable), as well as checking that <node> specifies a node that is
actually configured on the guest.

This controller provides a single PCIe port on a new root. It is
similar to pci-expander-bus, intended to provide a bus that can be
associated with a guest-identifiable NUMA node, but is for
machinetypes with PCIe rather than PCI (e.g. q35-based machinetypes).

Aside from PCIe vs. PCI, the other main difference is that a
pci-expander-bus has a companion pci-bridge that is automatically
attached along with it, but pcie-expander-bus has only a single port,
and that port will only connect to a pcie-root-port, or to a
pcie-switch-upstream-port. In order for the bus to be of any use in
the guest, it must have either a pcie-root-port or a
pcie-switch-upstream-port attached (and one or more
pcie-switch-downstream-ports attached to the
pcie-switch-upstream-port).

This is backed by the qemu device "pxb".

The pxb device always includes a pci-bridge that is at the bus number
of the pxb + 1.

busNr and <node> from the <target> subelement are used to set the
bus_nr and numa_node options for pxb.

During post-parse we validate that the domain's machinetype is
440fx-based (since the pxb device only works on 440fx-based machines),
and <node> also gets a sanity check to assure that the NUMA node
specified for the pxb (if any - it's optional) actually exists on the
guest.

This is a standard PCI root bus (not a bridge) that can be added to a
440fx-based domain. Although it uses a PCI slot, this is *not* how it
is connected into the PCI bus hierarchy, but is only used for
control. Each pci-expander-bus provides 32 slots (0-31) that can
accept hotplug of standard PCI devices.

The usefulness of pci-expander-bus relative to a pci-bridge is that
the NUMA node of the bus can be specified with the <node> subelement
of <target>. This gives guest-side visibility to the NUMA node of
attached devices (presuming that management apps only assign a device
to a bus that has a NUMA node number matching the node number of the
device on the host).

Each pci-expander-bus also has a "busNr" attribute. The expander-bus
itself will take the busNr specified, and all buses that are connected
to this bus (including the pci-bridge that is automatically added to
any expander bus of model "pxb" (see the next commit)) will use
busNr+1, busNr+2, etc, and the pci-root (or the expander-bus with next
lower busNr) will use bus numbers lower than busNr.

Since every PCI controller model has to have a default model name set,
put it in a separate function to clean up qemuDomainAssignPCIAddresses
a bit.

There are two places in qemu_domain_address.c where we have a switch
statement to convert PCI controller models
(VIR_DOMAIN_CONTROLLER_MODEL_PCI*) into the connection type flag that
is matched when looking for an upstream connection for that model of
controller (VIR_PCI_CONNECT_TYPE_*). This patch makes a utility
function in conf/domain_addr.c to do that, so that when a new PCI
controller is added, we only need to add the new model-->connect-type
in a single place.

The flags used to determine which devices could be plugged into which
controllers were quite confusing, as they tried to create classes of
connections, then put particular devices into possibly multiple
classes, while sometimes setting multiple flags for the controllers
themselves. The attempt to have a single flag indicate, e.g. that a
root-port or a switch-downstream-port could connect was not only
confusing, it was leading to a situation where it would be impossible
to specify exactly the right combinations for a new controller.

The solution is for the VIR_PCI_CONNECT_TYPE_* flags to have a 1:1
correspondence with each type of PCI controller, plus a flag for a PCI
endpoint device and another for a PCIe endpoint device (the only
exception to this is that pci-bridge and pcie-expander-bus controllers
have their upstream connection classified as
VIR_PCI_CONNECT_TYPE_PCI_DEVICE since they can be plugged into
*exactly* the same ports as any endpoint device).  Each device then
has a single flag for connect type (plus the HOTPLUG flag if that
device can e hotplugged), and each controller sets the CONNECT bits
for all controllers that can be plugged into it, as well as for either
type of endpoint device that can be plugged in (and the HOTPLUG flag
if it can accept hotplugged devices).

With this change, it is *slightly* easier to understand the matching
of connections (as long as you remember that the flag for a
device/upstream-facing connection of a controller is the same as that
device's type, while the flags for a controller's downstream
connections is the OR of all device types that can be plugged into
that controller). More importantly, it will be possible to correctly
specify what can be plugged into a pcie-switch-expander-bus, when
support for it is added.

Add new function to manage adding the controller -device options to the
command line removing that task from the mainline qemuBuildCommandLine.

Also adjust to using const virDomainDef instead of virDomainDefPtr.
This causes collateral damage in order to modify called APIs to use
the const virDomainDef instead as well.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

This does nothing more than adding the new device and capability.
The device is present since QEMU 2.6.0.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Create new modules qemu_domain_address.c and qemu_domain_address.h to
contain all the new functions and header data. Additionally move any
supporting static functions.

Make qemuDomainSupportsPCI non static.

Also, move and rename the following:

qemuSetSCSIControllerModel to qemuDomainSetSCSIControllerModel
qemuCollectPCIAddress to qemuDomainCollectPCIAddress
qemuValidateDevicePCISlotsPIIX3 to qemuDomainValidateDevicePCISlotsPIIX3
qemuAssignDevicePCISlots to qemuDomainAssignDevicePCISlots
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>