Frankly, this function is one big mess. A lot of arguments,
complicated behaviour. It's really surprising that arguments were
in random order (input and output arguments were mixed together),
the documentation was outdated, the description of return values
was bogus.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

libvirt was able to set the host_mtu option when an MTU was explicitly
given in the interface config (with <mtu size='n'/>), set the MTU of a
libvirt network in the network config (with the same named
subelement), and would automatically set the MTU of any tap device to
the MTU of the network.

This patch ties that all together (for networks based on tap devices
and either Linux host bridges or OVS bridges) by learning the MTU of
the network (i.e. the bridge) during qemuInterfaceBridgeConnect(), and
returning that value so that it can then be passed to
qemuBuildNicDevStr(); qemuBuildNicDevStr() then sets host_mtu in the
interface's commandline options.

The result is that a higher MTU for all guests connecting to a
particular network will be plumbed top to bottom by simply changing
the MTU of the network (in libvirt's config for libvirt-managed
networks, or directly on the bridge device for simple host bridges or
OVS bridges managed outside of libvirt).

One question I have about this - it occurred to me that in the case of
migrating a guest from a host with an older libvirt to one with a
newer libvirt, the guest may have *not* had the host_mtu option on the
older machine, but *will* have it on the newer machine. I'm curious if
this could lead to incompatibilities between source and destination (I
guess it all depends on whether or not the setting of host_mtu has a
practical effect on a guest that is already running - Maxime?)

Likewise, we could run into problems when migrating from a newer
libvirt to older libvirt - The guest would have been told of the
higher MTU on the newer libvirt, then migrated to a host that didn't
understand <mtu size='blah'/>. (If this really is a problem, it would
be a problem with or without the current patch).

Open /dev/vhost-scsi, and record the resulting file descriptor, so that
the guest has access to the host device outside of the libvirt daemon.
Pass this information, along with data parsed from the XML file, to build
a device string for the qemu command line.  That device string will be
for either a vhost-scsi-ccw device in the case of an s390 machine, or
vhost-scsi-pci for any others.
Signed-off-by: NEric Farman <farman@linux.vnet.ibm.com>

Propagate the selected or default level to qemu if it's supported.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1376009Signed-off-by: NPrasanna Kumar Kalever <prasanna.kalever@redhat.com>
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

QEMU added support for ivshmem-plain and ivshmem-doorbell.  Those are
reworked varians of legacy ivshmem that are compatible from the guest
POV, but not from host's POV and have sane specification and handling.

Details about the newer device type can be found in qemu's commit
5400c02b90bb:

  http://git.qemu.org/?p=qemu.git;a=commit;h=5400c02b90bbSigned-off-by: NMartin Kletzander <mkletzan@redhat.com>

Add the secret object so the 'passwordid=' can be added if the command line
if there's a secret defined in/on the host for TCP chardev TLS objects.

Preparation for the secret involves adding the secinfo to the char source
device prior to command line processing. There are multiple possibilities
for TCP chardev source backend usage.

Add test for at least a serial chardev as an example.

It isn't used anywhere else.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

previous commit:

  commit 2c322378
  Author: John Ferlan <jferlan@redhat.com>
  Date:   Mon Jun 13 12:30:34 2016 -0400

    qemu: Add the ability to hotplug the TLS X.509 environment

added a parameter "bool listen" in some methods. This
unfortunately clashes with the listen() method, causing
compile failures on certain platforms (RHEL-6 for example)
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

If the incoming XML defined a path to a TLS X.509 certificate environment,
add the necessary 'tls-creds-x509' object to the VIR_DOMAIN_CHR_TYPE_TCP
character device.

Likewise, if the environment exists the hot unplug needs adjustment as
well.  Note that all the return ret were changed to goto cleanup since
the cfg needs to be unref'd
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

For use on the monitor we need to format certain parts of the vcpu
private definition into a JSON object. Add a helper.

Since we already have a function that will generate the drivestr from
the alias, let's use it and remove the qemuDeviceDriveHostAlias.

Move the QEMU_DRIVE_HOST_PREFIX definition into qemu_alias.h

Also alter qemuAliasFromDisk to use the QEMU_DRIVE_HOST_PREFIX instead
of "drive-%s".

Need to create the object for a hotplug disk

It's not used externally anywhere else
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Put it into separate function called qemuDomainPrepareChannel() and call
it from the new qemuProcessPrepareDomain().
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Move the module from qemu_command.c to a new module virqemu.c and
rename the API to virQEMUBuildObjectCommandline.

This API will then be shareable with qemu-img and the need to build
a security object for luks support.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

We have been always setting the capability on if qemu has
QEMU_CAPS_DEVICE.

QEMU_CAPS_DEVICE is always set nowadays, so we can drop the
non-DEVICE code paths

Similar to the qemuDomainSecretDiskPrepare, generate the secret
for the Hostdev's prior to call qemuProcessLaunch which calls
qemuBuildCommandLine. Additionally, since the secret is not longer
added as part of building the command, the hotplug code will need
to make the call to add the secret in the hostdevPriv.

Since this then is the last requirement to pass a virConnectPtr
to qemuBuildCommandLine, we now can remove that as part of these
changes. That removal has cascading effects through various callers.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Rather than needing to pass the conn parameter to various command
line building API's, add qemuDomainSecretPrepare just prior to the
qemuProcessLaunch which calls qemuBuilCommandLine. The function
must be called after qemuProcessPrepareHost since it's expected
to eventually need the domain masterKey generated during the prepare
host call. Additionally, future patches may require device aliases
(assigned during the prepare domain call) in order to associate
the secret objects.

The qemuDomainSecretDestroy is called after the qemuProcessLaunch
finishes in order to clear and free memory used by the secrets
that were recently prepared, so they are not kept around in memory
too long.

Placing the setup here is beneficial for future patches which will
need the domain masterKey in order to generate an encrypted secret
along with an initialization vector to be saved and passed (since
the masterKey shouldn't be passed around).

Finally, since the secret is not added during command line build,
the hotplug code will need to get the secret into the private disk data.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

The values are currently limited to LLONG_MAX which causes some
problems.  QEMU conveniently changed their maximum to 1e15 (1 PB) which
is enough for some time and we need to adapt to that so that we don't
throw "Unknown error" messages.  Strictly limiting these values actually
fixes some corner case values (off-by-one checks in QEMU probably).

Since values out of the new specified range do not overflow anything,
change the type of error as well.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1317531Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Commit id '0da965c5' removed the 11th parameter, but neglected to
remove the ATTRIBUTE_NONNULL for it and adjust the 17th and 18th.

Now that there is just one format of the memory balloon command line
used the code can be merged into a single function.

Additionally with some tweaks to the control flow the code is easier to
read.

Essentially revert commit 3a6204cb which added these to allow the test
suite to pass without depending on the host system state.

Since commit 4b527c1a we already mock virSCSIDeviceGetSgName, so these
callbacks are useless.

The value is never negative thus there's no need to store it in a signed
type.

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

Also modify the qemuBuildRNGDevStr to use const virDomainDef instead
of virDomainDefPtr.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also modify the qemuBuildMemballoonDevStr to use const virDomainDef
instead of virDomainDefPtr.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also modify qemuBuildPCIHostdevDevStr, qemuBuildUSBHostdevDevStr,
and qemuBuildSCSIHostdevDevStr to use const virDomainDef instead
of virDomainDefPtr.

Make qemuBuildPCIHostdevPCIDevStr and qemuBuildUSBHostdevUSBDevStr
static to the qemu_command.c.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also move the qemuBuildRedirdevDevStr closer to the new function and
modify to use the const virDomainDef instead of virDomainDefPtr
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also since qemuBuildWatchdogDevStr was only local here, make it static as
well as modifying the const virDomainDef.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also since qemuBuildSoundDevStr was only local here, make it static as
well as modifying the const virDomainDef.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Make qemuBuildUSBInputDevStr static since only this module calls it.

Also the change to use const virDomainDef forces other changes.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Using const virDomainDef causes collateral damage in other called APIs
which need to make the similar adjustment
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

Add new function to manage adding the -fsdev options to the
command line removing that task from the mainline qemuBuildCommandLine.
Alter the code slightly to perform the !caps and fsdev failure check
up front.

Since both qemuBuildFSStr and qemuBuildFSDevStr are local, make them
static and fix their prototypes to use the const virDomainDef as well.
Make some minor formatting changes for long lines.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also since using const virDomainDef in new function, that means other
functions called needed to change their usage.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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

Also make qemuBuildHubDevStr static to the module since it's only
used here.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

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>

If use of virtlogd is enabled, then use it for backing the
character device log files too. This avoids the possibility
of a guest denial of service by writing too much data to
the log file.

Per-domain directories were introduced in order to be able to
completely separate security labels for each domain (commit
f1f68ca3).  However when the domain
name is long (let's say a ridiculous 110 characters), we cannot
connect to the monitor socket because on length of UNIX socket address
is limited.  In order to get around this, let's shorten it in similar
fashion and in order to avoid conflicts, throw in an ID there as well.
Also save that into the status XML and load the old status XMLs
properly (to clean up after older domains).  That way we can change it
in the future.

The shortening can be seen in qemuxml2argv tests, for example in the
hugepages-pages2 case.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Which is the only user. That was the only reason for including
qemu_command.h, though we need to explicitly include qemu_domain.h
afterwards.