When libvirt's virDomainDestroy API is shutting down the qemu process,
it first sends SIGTERM, then waits for 1.6 seconds and, if it sees the
process still there, sends a SIGKILL.

There have been reports that this behavior can lead to data loss
because the guest running in qemu doesn't have time to flush its disk
cache buffers before it's unceremoniously whacked.

This patch maintains that default behavior, but provides a new flag
VIR_DOMAIN_DESTROY_GRACEFUL to alter the behavior. If this flag is set
in the call to virDomainDestroyFlags, SIGKILL will never be sent to
the qemu process; instead, if the timeout is reached and the qemu
process still exists, virDomainDestroy will return an error.

Once this patch is in, the recommended method for applications to call
virDomainDestroyFlags will be with VIR_DOMAIN_DESTROY_GRACEFUL
included. If that fails, then the application can decide if and when
to call virDomainDestroyFlags again without
VIR_DOMAIN_DESTROY_GRACEFUL (to force the issue with SIGKILL).

(Note that this does not address the issue of existing applications
that have not yet been modified to use VIR_DOMAIN_DESTROY_GRACEFUL.
That is a separate patch.)

compat{a->i}bility
erron{->e}ous
nec{c->}essary.
Either "the" or "a".
Signed-off-by: NPhilipp Hahn <hahn@univention.de>

Qemu is adding the ability to do a partial rebase.  That is, given:

base <- intermediate <- current

virDomainBlockPull will produce:

current

but qemu now has the ability to leave base in the chain, to produce:

base <- current

Note that current qemu can only do a forward merge, and only with
the current image as the destination, which is fully described by
this API without flags.  But in the future, it may be possible to
enhance this API for additional scenarios by using flags:

Merging the current image back into a previous image (that is,
undoing a live snapshot), could be done by passing base as the
destination and flags with a bit requesting a backward merge.

Merging any other part of the image chain, whether forwards (the
backing image contents are pulled into the newer file) or backwards
(the deltas recorded in the newer file are merged back into the
backing file), could also be done by passing a new flag that says
that base should be treated as an XML snippet rather than an
absolute path name, where the XML could then supply the additional
instructions of which part of the image chain is being merged into
any other part.

* include/libvirt/libvirt.h.in (virDomainBlockRebase): New
declaration.
* src/libvirt.c (virDomainBlockRebase): Implement it.
* src/libvirt_public.syms (LIBVIRT_0.9.10): Export it.
* src/driver.h (virDrvDomainBlockRebase): New driver callback.
* src/rpc/gendispatch.pl (long_legacy): Add exemption.
* docs/apibuild.py (long_legacy_functions): Likewise.

This patch adds API to modify domain metadata for running and stopped
domains. The api supports changing description, title as well as the
newly added <metadata> element. The API has support for storing data in
the metadata element using xml namespaces.

* include/libvirt/libvirt.h.in
* src/libvirt_public.syms
        - add function headers
        - add enum to select metadata to operate on
        - export functions
* src/libvirt.c
        - add public api implementation
* src/driver.h
        - add driver support
* src/remote/remote_driver.c
* src/remote/remote_protocol.x
        - wire up the remote protocol
* include/libvirt/virterror.h
* src/util/virterror.c
        - add a new error message note that metadata for domain are
        missing

We already provide ways to detect when a domain has been paused as a
result of I/O error, but there was no way of getting the exact error or
even the device that experienced it.  This new API may be used for both.

which contained some useless lines, copied code, NULL
dereference.

Our existing virDomainBlockResize takes an unsigned long long
argument; if that command is later taught a DELTA and SHRINK flag,
we cannot change its type without breaking API (but at least such
a change would be ABI compatible).  Meanwhile, the only time a
negative size makes sense is if both DELTA and SHRINK are used
together, but if we keep the argument unsigned, applications can
pass the positive delta amount by which they would like to shrink
the system, and have the flags imply the negative value.  So,
since this API has not yet been released, and in the interest of
consistency with existing API, we swap virStorageVolResize to
always pass an unsigned value.

* include/libvirt/libvirt.h.in (virStorageVolResize): Use unsigned
argument.
* src/libvirt.c (virStorageVolResize): Likewise.
* src/driver.h (virDrvStorageVolUpload): Adjust clients.
* src/remote/remote_protocol.x (remote_storage_vol_resize_args):
Likewise.
* src/remote_protocol-structs: Regenerate.
Suggested by Daniel P. Berrange.

Unlike other users of virTypedParameter with RPC, this interface
can return zero-filled entries because the interface assumes
2 dimensional array. We compress these entries out from the
server when generating the over-the-wire contents, then reconstitute
them in the client.
Signed-off-by: NEric Blake <eblake@redhat.com>

* src/libvirt.c (virDomainPMSuspendForDuration): Clarify usage.

add new API virDomainGetCPUStats() for getting cpu accounting information
per real cpus which is used by a domain.  The API is designed to allow
future extensions for additional statistics.

based on ideas by Lai Jiangshan and Eric Blake.

* src/libvirt_public.syms: add API for LIBVIRT_0.9.10
* src/libvirt.c: define virDomainGetCPUStats()
* include/libvirt/libvirt.h.in: add virDomainGetCPUStats() header
* src/driver.h: add driver API
* python/generator.py: add python API (as not implemented)
Signed-off-by: NEric Blake <eblake@redhat.com>

This API allows a domain to be put into one of S# ACPI states.
Currently, S3 and S4 are supported. These states are shared
with virNodeSuspendForDuration.
However, for now we don't support any duration other than zero.
The same apply for flags.

Add a new function to allow changing of capacity of storage volumes.
Plan out several flags, even if not all of them will be implemented
up front.

Expose the new command via 'virsh vol-resize'.
Signed-off-by: NEric Blake <eblake@redhat.com>

The old virRandom() API was not generating good random numbers.
Replace it with a new API virRandomBits which instead of being
told the upper limit, gets told the number of bits of randomness
required.

* src/util/virrandom.c, src/util/virrandom.h: Add virRandomBits,
  and move virRandomInitialize
* src/util/util.h, src/util/util.c: Delete virRandom and
  virRandomInitialize
* src/libvirt.c, src/security/security_selinux.c,
  src/test/test_driver.c, src/util/iohelper.c: Update for
  changes from virRandom to virRandomBits
* src/storage/storage_backend_iscsi.c: Remove bogus call
  to virRandomInitialize & convert to virRandomBits

Currently, we support only filling a volume with zeroes on wiping.
However, it is not enough as data might still be readable by
experienced and equipped attacker. Many technical papers have been
written, therefore we should support other wiping algorithms.

With this flag, virDomainSnapshotCreate will use fs-freeze and
fs-thaw guest agent commands to quiesce guest's disks.

Add a new API virDomainShutdownFlags and define:

    VIR_DOMAIN_SHUTDOWN_DEFAULT        = 0,
    VIR_DOMAIN_SHUTDOWN_ACPI_POWER_BTN = (1 << 0),
    VIR_DOMAIN_SHUTDOWN_GUEST_AGENT    = (1 << 1),

Also define some flags for the reboot API

    VIR_DOMAIN_REBOOT_DEFAULT        = 0,
    VIR_DOMAIN_REBOOT_ACPI_POWER_BTN = (1 << 0),
    VIR_DOMAIN_REBOOT_GUEST_AGENT    = (1 << 1),

Although these two APIs currently have the same flags, using
separate enums allows them to expand separately in the future.

Add stub impls of the new API for all existing drivers

Commit 5d784bd6 was a nice attempt to
clarify the semantics by requiring domain name from dxml to either match
original name or dname. However, setting dxml domain name to dname
doesn't really work since destination host needs to know the original
domain name to be able to use it in migration cookies. This patch
requires domain name in dxml to match the original domain name. The
change should be safe and backward compatible since migration would fail
just a bit later in the process.

The above option helps to differentiate between implicit and explicit
interface pools.

When disk snapshots were first implemented, libvirt blindly refused
to allow an external snapshot destination that already exists, since
qemu will blindly overwrite the contents of that file during the
snapshot_blkdev monitor command, and we don't like a default of
data loss by default.  But VDSM has a scenario where NFS permissions
are intentionally set so that the destination file can only be
created by the management machine, and not the machine where the
guest is running, so that libvirt will necessarily see the destination
file already existing; adding a flag will allow VDSM to force the file
reuse without libvirt complaining of possible data loss.

https://bugzilla.redhat.com/show_bug.cgi?id=767104

* include/libvirt/libvirt.h.in (virDomainSnapshotCreateFlags): Add
VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.  Add
note about partial failure.
* tools/virsh.c (cmdSnapshotCreate, cmdSnapshotCreateAs): Add new
flag.
* tools/virsh.pod (snapshot-create, snapshot-create-as): Document
it.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDiskPrepare)
(qemuDomainSnapshotCreateXML): Implement the new flag.

We had loads of different styles in describing the @flags parameter
for various APIs, as well as several APIs that didn't list which
enums provided the bit values valid for the flags.

The end result is one of two formats:
@flags: bitwise-OR of vir...Flags
@flags: extra flags; not used yet, so callers should always pass 0

* src/libvirt.c: Use common sentences for flags.  Also,
(virDomainGetBlockIoTune): Mention virTypedParameterFlags.
(virConnectOpenAuth): Mention virConnectFlags.
(virDomainMigrate, virDomainMigrate2, virDomainMigrateToURI)
(virDomainMigrateToURI2): Mention virDomainMigrateFlags.
(virDomainMemoryPeek): Mention virDomainMemoryFlags.
(virStoragePoolBuild): Mention virStoragePoolBuildFlags.
(virStoragePoolDelete): Mention virStoragePoolDeleteFlags.
(virStreamNew): Mention virStreamFlags.
(virDomainOpenGraphics): Mention virDomainOpenGraphicsFlags.

I previously mentioned [1] a PolicyKit issue where libvirt would
proceed with authentication even though polkit-auth failed:

testusr xen134:~> virsh list --all
Attempting to obtain authorization for org.libvirt.unix.manage.
polkit-grant-helper: given auth type (8 -> yes) is bogus
Failed to obtain authorization for org.libvirt.unix.manage.
 Id Name                 State
----------------------------------
  0 Domain-0             running
  - sles11sp1-pv         shut off

AFAICT, libvirt attempts to obtain a privilege it already has,
causing polkit-auth to fail with above message.  Instead of calling
obtain and then checking auth, IMO the workflow should be for the
server to check auth first, and if that fails ask the client to
obtain it and check again.  This workflow also allows for checking
only successful exit of polkit-auth in virConnectAuthGainPolkit().

[1] https://www.redhat.com/archives/libvir-list/2011-December/msg00837.html

https://bugzilla.redhat.com/show_bug.cgi?id=770954

Most severe here is a latent (but currently untriggered) memory leak
if any hypervisor ever adds a string interface property; the
remainder are mainly cosmetic.

* include/libvirt/libvirt.h.in (VIR_DOMAIN_BANDWIDTH_*): Move
macros closer to interface that uses them, and document type.
* src/libvirt.c (virDomainSetInterfaceParameters)
(virDomainGetInterfaceParameters): Formatting tweaks.
* daemon/remote.c (remoteDispatchDomainGetInterfaceParameters):
Avoid memory leak.
* src/libvirt_public.syms (LIBVIRT_0.9.9): Sort lines.
* src/libvirt_private.syms (domain_conf.h): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSetInterfaceParameters): Fix
comments, break long lines.

* src/libvirt.c: implement the main entry points

Set up the types for the numa functions and insert them into the
virDriver structure definition.

It's referring to virSuspendDomain instead of
virDomainSuspend.

* src/libvirt.c: Free user directory path

This patch add new pulic API virDomainSetBlockIoTune and
virDomainGetBlockIoTune.
Signed-off-by: NLei Li <lilei@linux.vnet.ibm.com>
Signed-off-by: NZhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

Drivers were inconsistent when presented both --live and --config
at once.  For example, within qemu, getting memory parameters
favored live, getting blkio tuning favored config, and getting
scheduler parameters errored out.  Also, some, but not all,
attempts to mix flags on query were filtered at the virsh level.
We shouldn't have to duplicate efforts in every client app, nor
in every driver.  So, it is simpler to just enforce that the two
flags cannot both be used at once on query operations, which has
precedent in libvirt.c, and which matches the documentation of
virDomainModificationImpact.

* src/libvirt.c (virDomainGetMemoryParameters)
(virDomainGetBlkioParameters)
(virDomainGetSchedulerParametersFlags, virDomainGetVcpuPinInfo):
Borrow sanity checking from virDomainGetVcpusFlags.

The new API is named as "virDomainBlockResize", intending to add
support for qemu monitor command "block_resize" (both HMP and QMP).

Similar with APIs like "virDomainSetMemoryFlags", the units for
argument "size" is kilobytes.

Add the core functions that implement the functionality of the API.
Suspend is done by using an asynchronous mechanism so that we can return
the status to the caller before the host gets suspended. This asynchronous
operation is achieved by suspending the host in a separate thread of
execution. However, returning the status to the caller is only best-effort,
but not guaranteed.

To resume the host, an RTC alarm is set up (based on how long we want to
suspend) before suspending the host. When this alarm fires, the host
gets woken up.

Suspend-to-RAM operation on a host running Linux can take upto more than 20
seconds, depending on the load of the system. (Freezing of tasks, an operation
preceding any suspend operation, is given up after a 20 second timeout).
And Suspend-to-Disk can take even more time, considering the time required
for compaction, creating the memory image and writing it to disk etc.
So, we do not allow the user to specify a suspend duration of less than 60
seconds, to be on the safer side, since we don't want to prematurely declare
failure when we only had to wait for some more time.

Implement the public definitions for the new API
virNodeSuspendForDuration() which will be subsequently used to
do a timed suspend on the host.

This API can be used to check if the socket associated with
virConnectPtr is still open or it was closed (probably because keepalive
protocol timed out). If there the connection is local (i.e., no socket
is associated with the connection, it is trivially always alive.

virConnectSetKeepAlive public API can be used by a client connecting to
remote server to start using keepalive protocol. The API is handled
directly by remote driver and not transmitted over the wire to the
server.

Given that we can now handle the target's disk shorthand, in addition
to an absolute path to the file or block device used on the host,
the term 'disk' fits a bit better as the parameter name than 'path'.

* include/libvirt/libvirt.h.in: Update some parameter names.
* src/libvirt.c (virDomainBlockStats, virDomainBlockStatsFlags)
(virDomainBlockPeek, virDomainGetBlockInfo, virDomainBlockJobAbort)
(virDomainGetBlockJobInfo, virDomainBlockJobSetSpeed)
(virDomainBlockPull): Likewise.

Commit 89b6284f made it possible to pass either a source name or
the target device to most API demanding a disk designation, but
forgot to update the documentation.  It also failed to update
virDomainBlockStats to take both forms. This patch fixes both the
documentation and the remaining function.

Xen continues to use just device shorthand (that is, I did not
implement path lookup there, since xen does not track a domain_conf
to quickly tie a path back to the device shorthand).

* src/libvirt.c (virDomainBlockStats, virDomainBlockStatsFlags)
(virDomainGetBlockInfo, virDomainBlockPeek)
(virDomainBlockJobAbort, virDomainGetBlockJobInfo)
(virDomainBlockJobSetSpeed, virDomainBlockPull): Document
acceptable disk naming conventions.
* src/qemu/qemu_driver.c (qemuDomainBlockStats)
(qemuDomainBlockStatsFlags): Allow lookup by source name.
* src/test/test_driver.c (testDomainBlockStats): Likewise.

Signed-off-by: NEli Qiao <taget@linux.vnet.ibm.com>

When configuring a URI alias like this in 'libvirt.conf':

uri_aliases = [
  "jj#j=qemu+ssh://root@127.0.0.1/system",
  "sleet=qemu+ssh://root@sleet.cloud.example.com/system",
]
virsh -c jj#j

It will show this error message:
'no connection driver available for No connection for URI jj#j'
Actually，we expect this message below：
Malformed 'uri_aliases' config entry 'jj#j=qemu+ssh://root@127.0.0.1/system', aliases may only contain 'a-Z, 0-9, _, -'

Give this patch to fix this error.

This allows strings to be transported between client and server
in the context of name-type-value virTypedParameter functions.
For compatibility,

    o new clients will not send strings to old servers, based on
      a feature check
    o new servers will not send strings to old clients without the
      flag VIR_TYPED_PARAM_STRING_OKAY; this will be enforced at
      the RPC layer in the next patch, so that drivers need not
      worry about it in general.  The one exception is that
      virDomainGetSchedulerParameters lacks a flags argument, so
      it must not return a string; drivers that forward that
      function on to virDomainGetSchedulerParametersFlags will
      have to pay attention to the flag.
    o the flag VIR_TYPED_PARAM_STRING_OKAY is set automatically,
      based on a feature check (so far, no driver implements it),
      so clients do not have to worry about it

Future patches can then enable the feature on a per-driver basis.

This patch also ensures that drivers can blindly strdup() field
names (previously, a malicious client could stuff 80 non-NUL bytes
into field and cause a read overrun).

* src/libvirt_internal.h (VIR_DRV_FEATURE_TYPED_PARAM_STRING): New
driver feature.
* src/libvirt.c (virTypedParameterValidateSet)
(virTypedParameterSanitizeGet): New helper functions.
(virDomainSetMemoryParameters, virDomainSetBlkioParameters)
(virDomainSetSchedulerParameters)
(virDomainSetSchedulerParametersFlags)
(virDomainGetMemoryParameters, virDomainGetBlkioParameters)
(virDomainGetSchedulerParameters)
(virDomainGetSchedulerParametersFlags, virDomainBlockStatsFlags):
Use them.
* src/util/util.h (virTypedParameterArrayClear): New helper
function.
* src/util/util.c (virTypedParameterArrayClear): Implement it.
* src/libvirt_private.syms (util.h): Export it.
Based on an initial patch by Hu Tao, with feedback from
Daniel P. Berrange.
Signed-off-by: NEric Blake <eblake@redhat.com>

virDomainBlockStatsFlags was missing a check that was present in
virDomainGetMemoryParameters.  Additionally, I found that the
existing descriptions were a bit hard to read.  A later patch
will fix qemu to return fewer than max parameters if @nparams
was too small on input.

* src/libvirt.c (virDomainGetMemoryParameters)
(virDomainGetBlkioParameters, virDomainGetSchedulerParameters)
(virDomainGetSchedulerParametersFlags):
Tweak documentation wording.
(virDomainBlockStatsFlags): Likewise, and add sanity check.