Relatively straight-forward.  And since qemu was already using
VIR_DOMAIN_SNAPSHOT_FILTERS_ALL, with 6 different APIs all calling
into this common code, I've instantly added all 5 flags to 6 APIs.

* src/conf/snapshot_conf.h (VIR_DOMAIN_SNAPSHOT_FILTERS_ALL):
Enable new filters.
* src/conf/snapshot_conf.c (virDomainSnapshotObjListGetNames):
Prep the new flags.
(virDomainSnapshotObjListCopyNames): Actually do the filtering.

As we enable more modes of snapshot creation, it becomes more important
to be able to quickly filter based on snapshot properties.  This patch
introduces new filter flags; subsequent patches will introduce virsh
back-compat filtering, as well as actual libvirt filtering.

* include/libvirt/libvirt.h.in (virDomainSnapshotListFlags): Add
five new flags in two new groups.
* src/libvirt.c (virDomainSnapshotNum, virDomainSnapshotListNames)
(virDomainListAllSnapshots, virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames)
(virDomainSnapshotListAllChildren): Document them.
* src/conf/snapshot_conf.h (VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS)
(VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION): Add new convenience filter
collection macros.
* tools/virsh-snapshot.c (cmdSnapshotList): Add 5 new flags.
* tools/virsh.pod (snapshot-list): Document them.

This resolves:

  https://bugzilla.redhat.com/show_bug.cgi?id=873134

The reported problem is that an attempt to restore a saved domain that
was configured with <currentMemory> and <memory> set to some (same for
both) number that's not a multiple of 4096KiB results in an error like
this:

  error: Failed to start domain libvirt_test_api
  error: XML error: current memory '4001792k' exceeds maximum '4000768k'

(in this case, currentMemory was set to 4000000KiB).

The reason for this failure is:

1) a saved image contains the "live xml" of the domain at the time of
the save.

2) the live xml of a running domain gets its currentMemory
(a.k.a. cur_balloon) directly from the qemu monitor rather than from
the configuration of the domain.

3) the value reported by qemu is (sometimes) not exactly what was
originally given to qemu when the domain was started, but is rounded
up to [some indeterminate granularity] - in some versions of qemu that
granularity is apparently 1MiB, and in others it is 4MiB.

4) When the XML is parsed to setup the state of the restored domain,
the XML parser for <currentMemory> compares it to <memory> (which is
the maximum allowed memory size for the domain) and if <currentMemory>
is greater than the next 1024KiB boundary above <memory>, it spits out
an error and fails.

For example (from the BZ) if you start qemu on RHEL6 with both
<currentMemory> and <memory> of 4000000 (this number is in KiB),
libvirt's dominfo or dumpxml will report "4001792" back (rounded up to
next 4MiB) for 10-20 seconds after the start, then revert to reporting
"4000000". On Fedora 16 (which uses qemu-1.0), it will instead report
"4000768" (rounded up to next 1MiB). On Fedora 17 (qemu-1.2), it seems
to always report "4000000". ("4000000" is of course okay, and
"4000768" is also okay since that's the next 1024KiB boundary above
"4000000" and the parser was already allowing for that. But "4001792
is *not* okay and produces the error message.)

This patch solves the problem by changing the allowed "fudge factor"
when parsing from 1024KiB to 4096KiB to match the maximum up-rounding
that could be done in qemu.

(I had earlier thought to fix this by up-rounding <memory> in the
dumpxml that's put into the saved image, but that wouldn't have fixed
the case where the save image was produced by an "unfixed"
libvirtd.)

Prior to this patch, 'virsh nodecpumap' on older kernels reported:
error: Unable to get cpu map
error: out of memory

* src/nodeinfo.c (linuxParseCPUmax): Don't overwrite error.
(nodeGetCPUBitmap): Provide backup implementation.

On RHEL 5, I was getting a segfault trying to start libvirtd,
because we were failing virNodeParseSocket but not checking
for errors, and then calling CPU_SET(-1, &sock_map) as a result.
But if you don't have a topology/physical_package_id file,
then you can just assume that the cpu belongs to socket 0.

* src/nodeinfo.c (virNodeGetCpuValue): Change bool into
default_value.
(virNodeParseSocket): Allow for default value when file is missing,
different from fatal error on reading file.
(virNodeParseNode): Update call sites to fail on error.

For disk snapshots, the user could request an external snapshot
but not supply a filename; later on, we would check this condition
and generate a suitable name if possible, or gracefully error out
when not possible (such as when the original file was a block
device).  But unless we come up with a suitable way to generate
external memory file names, we have no later code point that was
checking for NULL, so we should forbid this up front.

* src/conf/snapshot_conf.c (virDomainSnapshotDefParseString):
Avoid NULL deref, since we don't generate names yet.

Signed-off-by: Nliguang <lig.fnst@cn.fujitsu.com>

It may take some time for sanlock to add a lockspace. And if user
restart libvirtd service meanwhile, the fresh daemon can fail adding
the same lockspace with EINPROGRESS. Recent sanlock has
sanlock_inq_lockspace() function which should block until lockspace
changes state. If we are building against older sanlock we should
retry a few times before claiming an error. This issue can be easily
reproduced:

for i in {1..1000} ; do echo $i; service libvirtd restart; sleep 2; done
20
Stopping libvirtd daemon:                                  [FAILED]
Starting libvirtd daemon:                                  [  OK  ]
21
Stopping libvirtd daemon:                                  [  OK  ]
Starting libvirtd daemon:                                  [  OK  ]
22
Stopping libvirtd daemon:                                  [  OK  ]
Starting libvirtd daemon:                                  [  OK  ]

 error : virLockManagerSanlockSetupLockspace:334 : Unable to add
 lockspace /var/lib/libvirt/sanlock/__LIBVIRT__DISKS__: Operation now in
 progress

The drivers for QEMU and LXC use virNodeGetInfo only to determine
the number of host CPUs. On Linux hosts nodeGetCPUCount has less
overhead.

Since /sys/devices/system/cpu/present is not available on
older kernels like on RHEL 5.x nodeGetCPUCount will
fail there. The fallback implemented is to scan for
/sys/devices/system/cpu/cpuNN entries.
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

This simplifies the top-level code, at the cost of using a little more
stack space.  The primary benefit is being able to send more fields
without knowing in advance how many of them, and of which types, these
fields will be, and without having to individually add buffer variables.

The code imposes an upper limit on the total number of iovs/buffers
used, and fields that wouldn't fit are silently dropped.  This is not
significant in this patch, but will affect the following one.
Signed-off-by: NMiloslav Trmač <mitr@redhat.com>

... and update all users.  No change in functionality, the parameter
will be used in the next patch.
Signed-off-by: NMiloslav Trmač <mitr@redhat.com>

... and update all users.  No change in functionality, the parameter
will be used later.

The metadata representation is as minimal as possible, but requires
the caller to allocate an array on stack explicitly.

The alternative of using varargs in the virLogMessage() callers:
* Would not allow the caller to optionally omit some metadata elements,
  except by having two calls to virLogMessage.
* Would not be as type-safe (e.g. using int vs. size_t), and the compiler
  wouldn't be able to do type checking
* Depending on parameter order:
  a) virLogMessage(..., message format, message params...,
                   metadata..., NULL)
     can not be portably implemented (parse_printf_format() is a glibc
     function)
  b) virLogMessage(..., metadata..., NULL,
                   message format, message params...)
     would prevent usage of ATTRIBUTE_FMT_PRINTF and the associated
     compiler checking.
Signed-off-by: NMiloslav Trmač <mitr@redhat.com>

Allow bootindex to be specified for redirected USB devices and host USB
devices.

Bug: https://bugzilla.redhat.com/show_bug.cgi?id=805414

The "restart" function for locks allocates a new array according to
and pre-sets its length, then reads the owner pids from a JSON
document in a loop. Rather than adding each owner at a different
index, though, it repeatedly overwrites the last element of the array
with all the owners.

The lack of initialization of 'opts' caused a SEGV in the
cleanup: path if the root->src directory did not exist

If domain uses only TLS port we don't want to add
'port=0' explicitly to command line.

This patch adds a helper to determine if snapshots are external and uses
the helper to fix detection of those in snapshot deletion code.

Snapshots are external if they have an external memory image or if the
disk locations are external. As mixed snapshots are forbidden for now
we need to check just one disk to know.

Lately there were a few reports of the output of the virsh nodeinfo
command being inaccurate. This patch tries to avoid that by checking if
the topology actually makes sense. If it doesn't we then report a
synthetic topology that indicates to the user that the host capabilities
should be checked for the actual topology.

This API was never synchronous and probably doesn't even need to be.

Currently, if user calls virDomainAbortJob we just issue
'migrate_cancel' and hope for the best. However, if user calls
the API in wrong phase when migration hasn't been started yet
(perform phase) the cancel request is just ignored. With this
patch, the request is remembered and as soon as perform phase
starts, migration is cancelled.

For S390, the default console target type cannot be of type 'serial'.
It is necessary to at least interpret the 'arch' attribute
value of the os/type element to produce the correct default type.

Therefore we need to extend the signature of defaultConsoleTargetType
to account for architecture. As a consequence all the drivers
supporting this capability function must be updated.

Despite the amount of changed files, the only change in behavior is
that for S390 the default console target type will be 'virtio'.

N.B.: A more future-proof approach could be to to use hypervisor
specific capabilities to determine the best possible console type.
For instance one could add an opaque private data pointer to the
virCaps structure (in case of QEMU to hold capsCache) which could
then be passed to the defaultConsoleTargetType callback to determine
the console target type.
Seems to be however a bit overengineered for the use case...
Signed-off-by: NViktor Mihajlovski <mihajlov@linux.vnet.ibm.com>

When the libvirt daemon is restarted it tries to reconnect to running
qemu domains. Since commit d38897a5 the
re-connection code runs in separate threads. In the original
implementation the maximum of domain ID's (that is used as an
initializer for numbering guests created next) while libvirt was
reconnecting to the guest.

With the threaded implementation this opens a possibility for race
conditions with the thread that is autostarting guests. When there's a
guest running with id 1 and the daemon is restarted. The autostart code
is reached first and spawns the first guest that should be autostarted
as id 1. This results into the following unwanted situation:

 # virsh list
   Id    Name                           State
  ----------------------------------------------------
   1     guest1                         running
   1     guest2                         running

This patch extracts the detection code before the re-connection threads
are started so that the maximum id of the guests being reconnected to is
known.

The only semantic change created by this is if the guest with greatest ID
quits before we are able to reconnect it's ID is used anyway as the
greatest one as without this patch the greatest ID of a process we could
successfuly reconnect to would be used.

82507838 refactored the code to keep both the raw and canonicalized form
of the backingStore, which breaks badly when the storage pool contains a
storage volume, which is missing its backing store file:
 # ./daemon/libvirtd -l
 2012-11-07 12:43:33.279+0000: 22175: info : libvirt version: 1.0.0
 2012-11-07 12:43:33.279+0000: 22175: error : absolutePathFromBaseFile:542 : Can't canonicalize path '/var/lib/libvirt/images/base.qcow2': No such file or directory
 2012-11-07 12:43:33.280+0000: 22175: error : storageDriverAutostart:115 : Failed to autostart storage pool 'default': Can't canonicalize path '/var/lib/libvirt/images/base.qcow2': No such file or directory

This is because virStorageFileGetMetadataFromBuf() aborts with -1 if the
filename of the backingStore can not be canonicalized:
 #0  absolutePathFromBaseFile () at util/storage_file.c:541
 #1  virStorageFileGetMetadataFromBuf () at util/storage_file.c:728
 #2  virStorageFileGetMetadataFromFD () at util/storage_file.c:932
 #3  virStorageBackendProbeTarget () at storage/storage_backend_fs.c:94
 #4  virStorageBackendFileSystemRefresh () at storage/storage_backend_fs.c:849
 #5  storagePoolStart () at storage/storage_driver.c:700
 #6  virStoragePoolCreate () at libvirt.c:12471
 ...

Treat files which miss their backing file as standalone files.
Signed-off-by: NPhilipp Hahn <hahn@univention.de>

Headers of qemuDomainSnapshotLoad and qemuDomainNetsRestart were
improperly formatted.

This patch adds support for external disk snapshots of inactive domains.
The snapshot is created by calling using qemu-img by calling:

 qemu-img create -f format_of_snapshot -o
 backing_file=/path/to/src,backing_fmt=format_of_backing_image
 /path/to/snapshot

in case the backing image format is known or probing is allowed and
otherwise:

 qemu-img create -f format_of_snapshot -o  backing_file=/path/to/src
 /path/to/snapshot

on each of the disks selected for snapshotting. This patch also modifies
the snapshot preparing function to support creating external snapshots
and to sanitize arguments. For now the user isn't able to mix external
and internal snapshots but this restriction might be lifted in the
future.

Some operations, APIs needs domain to be paused prior operation can be
performed, e.g. (managed-) save of a domain. The processors should be
restored in the end. However, if 'cont' fails for some reason, we log a
message but this is not sufficient as an event should be emitted as
well. Mgmt application can then decide what to do.

The code that was split out into the qemuDomainSaveMemory expands the
pointer containing the XML description of the domain that it gets from
higher layers. If the pointer changes the old one is invalid and the
upper layer function tries to free it causing an abort.

This patch changes the expansion of the original string to a new
allocation and copy of the contents.

After the connection to ESX 5.1 being broken since g1e7cd395, the fix
in bab7752c helped a bit, but still missed a spot, so the connection
is now successful, but some APIs (for example defineXML) don't work.
Two cases missing are added in this patch to avoid that.

qemu is sensitive to the order of arguments passed. Hence, if a
device requires a controller, the controller cmd string must
precede device cmd string. The same apply for controllers, when
for instance ccid controller requires usb controller. So
controllers create partial ordering in which they should be added
to qemu cmd line.

which just re-indent code and prepare it for next patch.

Some FDs may not implement fdatasync() functionality,
e.g.  pipes. In that case EINVAL or EROFS is returned.
We don't want to fail then nor report any error.
Reported-by: NChristophe Fergeau <cfergeau@redhat.com>

Some of the pre-snapshot check have restrictions wired in regarding
configuration options that influence taking of external checkpoints.

This patch removes restrictions that would inhibit taking of such a
snapshot.

This patch adds support to take external system checkpoints.

The functionality is layered on top of the previous disk-only snapshot
code. When the checkpoint is requested the domain memory is saved to the
memory image file using migration to file. (The user may specify to
take the memory image while the guest is live with the
VIR_DOMAIN_SNAPSHOT_CREATE_LIVE flag.)

The memory save image shares format with the image created by
virDomainSave() API.

Before now, libvirt supported only internal snapshots for active guests.
This patch renames this function to qemuDomainSnapshotCreateActiveInternal
to prepare the grounds for external active snapshots.

The new external system checkpoints will require an async job while the
snapshot is taken. This patch adds QEMU_ASYNC_JOB_SNAPSHOT to track this
job type.

The default behavior while creating external checkpoints is to pause the
guest while the memory state is captured. We want the users to sacrifice
space saving for creating the memory save image while the guest is live
to minimize downtime.

This patch adds a flag that causes the guest not to be paused before
taking the snapshot.
 *include/libvirt/libvirt.h.in:
    - add new paused reason: VIR_DOMAIN_PAUSED_SNAPSHOT
    - add new flag for taking snapshot: VIR_DOMAIN_SNAPSHOT_CREATE_LIVE
 *tools/virsh-domain-monitor.c:
    - add string representation for VIR_DOMAIN_PAUSED_SNAPSHOT
 *tools/virsh-snapshot.c:
    - add support for VIR_DOMAIN_SNAPSHOT_CREATE_LIVE
 *tools/virsh.pod:
    - add docs for --live option added to use
    VIR_DOMAIN_SNAPSHOT_CREATE_LIVE flag

The code that saves domain memory by migration to file can be reused
while doing external checkpoints of a machine. This patch extracts the
common code and places it in a separate function.

Two other places were left with the old code to look up snapshots.
Change them to use the snapshot lookup helper.