In the future we might need to track state of individual images. Move
the readonly and shared flags to the virStorageSource struct so that we
can keep them in a per-image basis.

Some of the further changes will propagate seclabels from a disk source
element into the backing store elements. This would change the XML
output of the backing store as the seclabels would be formatted for each
backing store element. Skip the seclabels formatting until we decide
that it's necessary.

Allow de-init of null storage sources.

Add a wrapper that determines the correct uid and gid for a certain
storage file and domain.

It will help re-using the function.

Now that we are able to select images from the backing chain via indexed
access we should also convert possible network sources to
qemu-compatible strings before passing them to qemu.

Now that we are able to select images from the backing chain via indexed
access we should also convert possible network sources to
qemu-compatible strings before passing them to qemu.

Introduce flag for the block rebase API to allow the rebase operation to
leave the chain relatively addressed. Also adds a virsh switch to enable
this behavior.

Introduce flag for the block commit API to allow the commit operation to
leave the chain relatively addressed. Also adds a virsh switch to enable
this behavior.

The qemu block info function relied on working with local storage. Break
this assumption by adding support for remote volumes. Unfortunately we
still need to take a hybrid approach as some of the operations require a
filedescriptor.

Previously you'd get:
 $ virsh domblkinfo gl vda
 error: cannot stat file '/img10': Bad file descriptor

Now you get some stats:
 $ virsh domblkinfo gl vda
 Capacity:       10485760
 Allocation:     197120
 Physical:       197120

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1110198

The gluster code had two functions for reading volume headers, remove
one and reuse the second one.

To allow reusing this function in the qemu driver we need to allow
specifying the storage format. Also separate return of the backing store
path now isn't necessary.

There was just one callsite left. Integrate the body to the only calling
function.

https://bugzilla.redhat.com/show_bug.cgi?id=1077009

For inactive domains, set both current and maximum memory
to the specified 'maximum memory' value.

This matches the behavior of QEMU driver's SetMaxMemory.

https://bugzilla.redhat.com/show_bug.cgi?id=1091132

Add startup auditing and also hotplug auditing for said devices.

For the regular dump operation we migrate the VM to a file. This won't
work when the VM has passthrough devices assigned. Rather than reporting
a cryptic error from qemu run our check whether it can be migrated.

This does not influence the memory-only dump that is allowed with
passthrough devices.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=874418

We invoked virCgroupHasController twice for checking
VIR_CGROUP_CONTROLLER_DEVICES
in lxcDomainAttachDeviceDiskLive.
Signed-off-by: NChen Hanxiao <chenhanxiao@cn.fujitsu.com>

Commits e18a80a3 and 57e5c3c2 switched from a getenv wrapper which
does not allocate a string to virFileFindResource which does not,
without freeing it.

https://bugzilla.redhat.com/show_bug.cgi?id=1116427

To allow changing the name that is recorded in the top of the current
image chain used in a block pull/rebase operation, we need to specify
the backing name to qemu. This is done via the "backing-file" attribute
to the block-stream commad.

To allow changing the name that is recorded in the overlay of the TOP
image used in a block commit operation, we need to specify the backing
name to qemu. This is done via the "backing-file" attribute to the
block-commit command.

This command allows to change the backing file name recorded in the
metadata of a qcow (or other) image. The capability also notifies that
the "block-stream" and "block-commit" commands understand the
"backing-file" attribute.

Pass the virStorageSource struct to the auditing function and check if
storage is local before auditing.

Extract common operations done when creating an audit message to a
separate generic function that can be reused and convert RNG, disk, FS
and net audit to use it.

The audit functions usually take the old definition before the new one
in the argument list. Unify RNG device to use the same order.

There's a lot of places where we skip doing actions based on the
locality of given storage type. The usual pattern is to skip it if:

virStorageSourceGetActualType(src) == VIR_STORAGE_TYPE_NETWORK

Add a simple helper to simplify the pattern to
virStorageSourceIsLocalStorage(src)

Replace the authType, chap, and cephx unions in virStoragePoolSource
with a single pointer to a virStorageAuthDefPtr.  Adjust all users of
the previous chap/cephx and secret unions with the source->auth data.

Replace the inline "auth" struct in virStorageSource with a pointer
to a virStorageAuthDefPtr and utilize between the domain_conf, qemu_conf,
and qemu_command sources for finding the auth data for a domain disk

Introduce virStorageAuthDef and friends.  Future patches will merge/utilize
their view of storage source/pool auth/secret definitions.

New API's include:
    virStorageAuthDefParse:  Parse the "<auth/>" XML data for either the
                             domain disk or storage pool returning a
                             virStorageAuthDefPtr
    virStorageAuthDefCopy:   Copy a virStorageAuthDefPtr - to be used by
                             the qemuTranslateDiskSourcePoolAuth when it
                             copies storage pool auth data into domain
                             disk auth data
    virStorageAuthDefFormat: Common output of the "<auth" in the domain
                             disk or storage pool XML
    virStorageAuthDefFree:   Free memory associated with virStorageAuthDef

Subsequent patches will utilize the new functions for the domain disk and
storage pools.

Future work in the hostdev pass through can then make use of common data
structures and code.

Use the probing functionality added in the last patch to turn on
a capability bit when active commit is present, and gate active
commit on that capability.

For my own reference: the difference between BLOCKJOB_SYNC and
BLOCKJOB_ASYNC is whether qemu generated an event at the
conclusion of blockpull; basically, RHEL 6.2 was the only release
of qemu that has the sync semantics and lacks the event.  RHEL
6.3 added blockcopy, but also picked up on the upstream style
of qemu generating events.  As no one is likely to backport
active commit to RHEL 6.2, it's safe for blockcommit to always
require async blockjob support.

Modifying qemucapabilitiestest is painful; the .replies files would
be so much easier if they had comments correlating which command
generated the given reply.  Maybe I'll fix that up later...

* src/qemu/qemu_capabilities.h (QEMU_CAPS_ACTIVE_COMMIT): New
capability.
* src/qemu/qemu_driver.c (qemuDomainBlockCommit): Use the new bit
* src/qemu/qemu_capabilities.c (virQEMUCaps): Name the new bit.
(virQEMUCapsProbeQMPCommands): Set it.
* tests/qemucapabilitiesdata/caps_1.3.1-1.replies: Update.
* tests/qemucapabilitiesdata/caps_1.4.2-1.replies: Likewise.
* tests/qemucapabilitiesdata/caps_1.5.3-1.replies: Likewise.
* tests/qemucapabilitiesdata/caps_1.6.0-1.replies: Likewise.
* tests/qemucapabilitiesdata/caps_1.6.50-1.replies: Likewise.
Signed-off-by: NEric Blake <eblake@redhat.com>

We are about to turn on support for active block commit.  Although
qemu 2.0 was the first version to mostly support it, that version
mis-handles 0-length files, and doesn't have anything available for
easy probing.  But qemu 2.1 fixed bugs, and made life simpler by
letting the 'top' argument be optional.  Unless someone begs for
active commit with qemu 2.0, for now we are just going to enable
it only by probing for qemu 2.1 behavior (anyone backporting active
commit can also backport the optional argument behavior).  This
requires qemu.git commit 7676e2c597000eff3a7233b40cca768b358f9bc9.

Although all our actual uses of block-commit supply arguments for
both base and top, we can omit both arguments and use a bogus
device string to trigger an interesting behavior in qemu.  All QMP
commands first do argument validation, failing with GenericError
if a mandatory argument is missing.  Once that passes, the code
in the specific command gets to do further checking, and the qemu
developers made sure that if device is the only supplied argument,
then the block-commit code will look up the device first, with a
failure of DeviceNotFound, before attempting any further argument
validation (most other validations fail with GenericError).  Thus,
the category of error class can reliably be used to decipher
whether the top argument was optional, which in turn implies a
working active commit.  Since we expect our bogus device string to
trigger an error either way, the code is written to return a
distinct return value without spamming the logs.

* src/qemu/qemu_monitor.h (qemuMonitorSupportsActiveCommit): New
prototype.
* src/qemu/qemu_monitor.c (qemuMonitorSupportsActiveCommit):
Implement it.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONBlockCommit):
Allow NULL for top and base, for probing purposes.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONBlockCommit):
Likewise, implementing the probe.
* tests/qemumonitorjsontest.c (mymain): Enable...
(testQemuMonitorJSONqemuMonitorSupportsActiveCommit): ...a new test.
Signed-off-by: NEric Blake <eblake@redhat.com>

So far only information on disks and host devices are exposed in the
capabilities XML. Well, at least something. Even a new test is
introduced. The qemu capabilities are stolen from already existing
qemucapabilities test. There's one tricky point though. Functions that
checks host's KVM and VFIO capabilities, are impossible to mock
currently. So in the test, we are setting the capabilities by hand.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

Sometimes it may be useful to get a default machine for given qemu
binary. Fortunately, the default machine is stored always on the first
position in the supported machines array.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This internal API is meant to answer the question 'Is this machine
type supported by given qemu?'.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

The API may come handy if somebody has an architecture and wants to
look through available qemus if the architecture is supported or not.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

The API should expose the information contained in virDomainCapsPtr.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

This new module holds and formats capabilities for emulator. If you
are about to create a new domain, you may want to know what is the
host or hypervisor capable of. To make sure we don't regress on the
XML, the formatting is not something left for each driver to
implement, rather there's general format function.

The domain capabilities is a lockable object (even though the locking
is not necessary yet) which uses reference counter.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

In the lastest rework (9e7ecabf) a cleanup label was left over which
results in compilation error.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>