Thanks to cgroups, providing user vs. system time of the overall
guest is easy to add to our existing API.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_CPU_STATS_USERTIME)
(VIR_DOMAIN_CPU_STATS_SYSTEMTIME): New constants.
* src/util/virtypedparam.h (virTypedParameterArrayValidate)
(virTypedParameterAssign): Enforce checking the result.
* src/qemu/qemu_driver.c (qemuDomainGetPercpuStats): Fix offender.
(qemuDomainGetTotalcpuStats): Implement new parameters.
* tools/virsh.c (cmdCPUStats): Tweak output accordingly.
Overflow can be user-induced, so it deserves more than being called
an internal error. Note that in general, 32-bit platforms have
far more places to trigger this error (anywhere the public API
used 'unsigned long' but the other side of the connection is a
64-bit server); but some are possible on 64-bit platforms (where
the public API computes the product of two numbers).
* include/libvirt/virterror.h (VIR_ERR_OVERFLOW): New error.
* src/util/virterror.c (virErrorMsg): Translate it.
* src/libvirt.c (virDomainSetVcpusFlags, virDomainGetVcpuPinInfo)
(virDomainGetVcpus, virDomainGetCPUStats): Use it.
* daemon/remote.c (HYPER_TO_TYPE): Likewise.
* src/qemu/qemu_driver.c (qemuDomainBlockResize): Likewise.
Qemu supports sizing by bytes; we shouldn't force the user to
round up if they really wanted an unaligned total size.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_BLOCK_RESIZE_BYTES):
New flag.
* src/libvirt.c (virDomainBlockResize): Document it.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONBlockResize): Take
size in bytes.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextBlockResize):
Likewise. Pass bytes, not megabytes, to monitor.
* src/qemu/qemu_driver.c (qemuDomainBlockResize): Implement new
flag.
No thanks to 64-bit windows, with 64-bit pid_t, we have to avoid
constructs like 'int pid'. Our API in libvirt-qemu cannot be
changed without breaking ABI; but then again, libvirt-qemu can
only be used on systems that support UNIX sockets, which rules
out Windows (even if qemu could be compiled there) - so for all
points on the call chain that interact with this API decision,
we require a different variable name to make it clear that we
audited the use for safety.
Adding a syntax-check rule only solves half the battle; anywhere
that uses printf on a pid_t still needs to be converted, but that
will be a separate patch.
* cfg.mk (sc_correct_id_types): New syntax check.
* src/libvirt-qemu.c (virDomainQemuAttach): Document why we didn't
use pid_t for pid, and validate for overflow.
* include/libvirt/libvirt-qemu.h (virDomainQemuAttach): Tweak name
for syntax check.
* src/vmware/vmware_conf.c (vmwareExtractPid): Likewise.
* src/driver.h (virDrvDomainQemuAttach): Likewise.
* tools/virsh.c (cmdQemuAttach): Likewise.
* src/remote/qemu_protocol.x (qemu_domain_attach_args): Likewise.
* src/qemu_protocol-structs (qemu_domain_attach_args): Likewise.
* src/util/cgroup.c (virCgroupPidCode, virCgroupKillInternal):
Likewise.
* src/qemu/qemu_command.c(qemuParseProcFileStrings): Likewise.
(qemuParseCommandLinePid): Use pid_t for pid.
* daemon/libvirtd.c (daemonForkIntoBackground): Likewise.
* src/conf/domain_conf.h (_virDomainObj): Likewise.
* src/probes.d (rpc_socket_new): Likewise.
* src/qemu/qemu_command.h (qemuParseCommandLinePid): Likewise.
* src/qemu/qemu_driver.c (qemudGetProcessInfo, qemuDomainAttach):
Likewise.
* src/qemu/qemu_process.c (qemuProcessAttach): Likewise.
* src/qemu/qemu_process.h (qemuProcessAttach): Likewise.
* src/uml/uml_driver.c (umlGetProcessInfo): Likewise.
* src/util/virnetdev.h (virNetDevSetNamespace): Likewise.
* src/util/virnetdev.c (virNetDevSetNamespace): Likewise.
* tests/testutils.c (virtTestCaptureProgramOutput): Likewise.
* src/conf/storage_conf.h (_virStoragePerms): Use mode_t, uid_t,
and gid_t rather than int.
* src/security/security_dac.c (virSecurityDACSetOwnership): Likewise.
* src/conf/storage_conf.c (virStorageDefParsePerms): Avoid
compiler warning.
This patch adds a set of flags to be used with the virDomainOpenConsole
API call to specify if the user wishes to interrupt an existing console
session or just to try open a new one.
VIR_DOMAIN_CONSOLE_SAFE - specifies that the console connection should
be opened only if the hypervisor supports
mutually exclusive access to console devices
VIR_DOMAIN_CONSOLE_FORCE - specifies that the caller wishes to interrupt
existing session and force a creation of a
new one.
This patch adds VIR_MIGRATE_UNSAFE flag for migration APIs and new
VIR_ERR_MIGRATION_UNSAFE error code. The error code should be returned
whenever migrating a domain is considered unsafe (e.g., it's configured
in a way that does not ensure data integrity once it is migrated).
VIR_MIGRATE_UNSAFE flag may be used to force migration even though it
would normally be considered unsafe and forbidden.
Unlike .cvsignore under CVS, git allows for ignoring nested
names. We weren't very consistent where new tests were
being ignored (some in .gitignore, some in tests/.gitignore),
and I found it easier to just consolidate everything.
* .gitignore: Subsume entries from subdirectories.
* daemon/.gitignore: Delete.
* docs/.gitignore: Likewise.
* docs/devhelp/.gitignore: Likewise.
* docs/html/.gitignore: Likewise.
* examples/dominfo/.gitignore: Likewise.
* examples/domsuspend/.gitignore: Likewise.
* examples/hellolibvirt/.gitignore: Likewise.
* examples/openauth/.gitignore: Likewise.
* examples/domain-events/events-c/.gitignore: Likewise.
* include/libvirt/.gitignore: Likewise.
* src/.gitignore: Likewise.
* src/esx/.gitignore: Likewise.
* tests/.gitignore: Likewise.
* tools/.gitignore: Likewise.
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.)
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.
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.
The bottom of the public header is reserved for deprecated APIs;
it's nicer to arrange things in logical groups.
* include/libvirt/libvirt.h.in (virConnectSetKeepAlive)
(virDomainGetCPUStats): Float earlier in the file.
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: Eric 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: Eric Blake <eblake@redhat.com>
And hook it up for policykit auth. This allows virt-manager to detect
that the user clicked the policykit 'cancel' button and not throw
an 'authentication failed' error message at the user.
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.
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
Although this is a public API break, it only affects users that
were compiling against *_LAST values, and can be trivially
worked around without impacting compilation against older
headers, by the user defining VIR_ENUM_SENTINELS before using
libvirt.h. It is not an ABI break, since enum values do not
appear as .so entry points. Meanwhile, it prevents users from
using non-stable enum values without explicitly acknowledging
the risk of doing so.
See this list discussion:
https://www.redhat.com/archives/libvir-list/2012-January/msg00804.html
* include/libvirt/libvirt.h.in: Hide all sentinels behind
LIBVIRT_ENUM_SENTINELS, and add missing sentinels.
* src/internal.h (VIR_DEPRECATED): Allow inclusion after
libvirt.h.
(LIBVIRT_ENUM_SENTINELS): Expose sentinels internally.
* daemon/libvirtd.h: Use the sentinels.
* src/remote/remote_protocol.x (includes): Don't expose sentinels.
* python/generator.py (enum): Likewise.
* tests/cputest.c (cpuTestCompResStr): Silence compiler warning.
* tools/virsh.c (vshDomainStateReasonToString)
(vshDomainControlStateToString): Likewise.
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.
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.
The APIs are used to set/get domain's network interface's parameters.
Currently supported parameters are bandwidth settings.
* include/libvirt/libvirt.h.in: new API and parameters definition
* python/generator.py: skip the Python API generation
* src/driver.h: add new entry to the driver structure
* src/libvirt_public.syms: export symbols
A generic error code was returned, if the user aborted a migration job.
This made it hard to distinguish between a user requested abort and an
error that might have occured. This patch introduces a new error code,
which is returned in the specific case of a user abort, while leaving
all other failures with their existing code. This makes it easier to
distinguish between failure while mirgrating and an user requested
abort.
* include/libvirt/virterror.h: - add new error code
* src/util/virterror.c: - add message for the new error code
* src/qemu/qemu_migration.h: - Emit operation aborted error instead of
operation failed, on migration abort
When QEMU guest finishes its shutdown sequence, qemu stops virtual CPUs
and when started with -no-shutdown waits for us to kill it using
SGITERM. Since QEMU is flushing its internal buffers, some time may pass
before QEMU actually dies. We mistakenly used "paused" state (and
events) for this which is quite confusing since users may see a domain
going to pause while they expect it to shutdown. Since we already have
"shutdown" state with "the domain is being shut down" semantics, we
should use it for this state.
However, the state didn't have a corresponding event so I created one
and called its detail as VIR_DOMAIN_EVENT_SHUTDOWN_FINISHED (guest OS
finished its shutdown sequence) with the intent to add
VIR_DOMAIN_EVENT_SHUTDOWN_STARTED in the future if we have a
sufficiently capable guest agent that can notify us when guest OS starts
to shutdown.
This patch adds binding for virNodeGetMemoryStats method of libvirtd.
Return value is represented as a python dictionary mapping field
names to values.
The VIR_NODE_SUSPEND_TARGET constants are not flags, so they
should just be assigned straightforward incrementing values.
* include/libvirt/libvirt.h.in: Change VIR_NODE_SUSPEND_TARGET
values
* src/util/virnodesuspend.c: Fix suspend target checks
This patch add new pulic API virDomainSetBlockIoTune and
virDomainGetBlockIoTune.
Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
This adds per-device weights to <blkiotune>. Note that the
cgroups implementation only supports weights per block device,
and not per-file within the device; hence this option must be
global to the domain definition rather than tied to individual
<devices>/<disk> entries:
<domain ...>
<blkiotune>
<device>
<path>/path/to/block</path>
<weight>1000</weight>
</device>
</blkiotune>
..
This patch also adds a parameter --device-weights to virsh command
blkiotune for setting/getting blkiotune.weight_device for any
hypervisor that supports it. All <device> entries under
<blkiotune> are concatenated into a single string attribute under
virDomain{Get,Set}BlkioParameters, named "device_weight".
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
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.
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.
This patch exports KVM Host Power Management capabilities as XML so that
higher-level systems management software can make use of these features
available in the host.
The script "pm-is-supported" (from pm-utils package) is run to discover if
Suspend-to-RAM (S3) or Suspend-to-Disk (S4) is supported by the host.
If either of them are supported, then a new tag "<power_management>" is
introduced in the XML under the <host> tag.
However in case the query to check for power management features succeeded,
but the host does not support any such feature, then the XML will contain
an empty <power_management/> tag. In the event that the PM query itself
failed, the XML will not contain any "power_management" tag.
To use this, new APIs could be implemented in libvirt to exploit power
management features such as S3/S4.
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: Eric Blake <eblake@redhat.com>
All constants related to events should have a prefix of
VIR_DOMAIN_EVENT_
* include/libvirt/libvirt.h.in, src/qemu/qemu_domain.c:
Rename VIR_DOMAIN_DISK_CHANGE_MISSING_ON_START to
VIR_DOMAIN_EVENT_DISK_CHANGE_MISSING_ON_START
Document the parameter names that will be used by
virDomain{Get,Set}SchedulerParameters{,Flags}, rather than
hard-coding those names in each driver, to match what is
done with memory, blkio, and blockstats parameters.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SCHEDULER_CPU_SHARES)
(VIR_DOMAIN_SCHEDULER_VCPU_PERIOD)
(VIR_DOMAIN_SCHEDULER_VCPU_QUOTA, VIR_DOMAIN_SCHEDULER_WEIGHT)
(VIR_DOMAIN_SCHEDULER_CAP, VIR_DOMAIN_SCHEDULER_RESERVATION)
(VIR_DOMAIN_SCHEDULER_LIMIT, VIR_DOMAIN_SCHEDULER_SHARES): New
field name macros.
* src/qemu/qemu_driver.c (qemuSetSchedulerParametersFlags)
(qemuGetSchedulerParametersFlags): Use new defines.
* src/test/test_driver.c (testDomainGetSchedulerParamsFlags)
(testDomainSetSchedulerParamsFlags): Likewise.
* src/xen/xen_hypervisor.c (xenHypervisorGetSchedulerParameters)
(xenHypervisorSetSchedulerParameters): Likewise.
* src/xen/xend_internal.c (xenDaemonGetSchedulerParameters)
(xenDaemonSetSchedulerParameters): Likewise.
* src/lxc/lxc_driver.c (lxcSetSchedulerParametersFlags)
(lxcGetSchedulerParametersFlags): Likewise.
* src/esx/esx_driver.c (esxDomainGetSchedulerParametersFlags)
(esxDomainSetSchedulerParametersFlags): Likewise.
* src/libxl/libxl_driver.c (libxlDomainGetSchedulerParametersFlags)
(libxlDomainSetSchedulerParametersFlags): Likewise.
Add a new secret type to store a Ceph authentication key. The name
is simply an identifier for easy human reference.
The xml looks like this:
<secret ephemeral='no' private='no'>
<uuid>0a81f5b2-8403-7b23-c8d6-21ccc2f80d6f</uuid>
<usage type='ceph'>
<name>mycluster_admin</name>
</usage>
</secret>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Josh Durgin <josh.durgin@dreamhost.net>
Not all VNC/SPICE servers use a TCP socket for their connections.
It is possible to configure a UNIX socket server. The graphics
event must thus include a UNIX socket address type.
* include/libvirt/libvirt.h.in: Add UNIX socket address type
for graphics event
* src/qemu/qemu_monitor_json.c: Add 'unix' string to address
type enum
The virDomainOpenGraphics API allows a libvirt client to pass in
a file descriptor for an open socket pair, and get it connected
to the graphics display of the guest. This is limited to working
with local libvirt hypervisors connected over a UNIX domain
socket, since it will use UNIX FD passing
* include/libvirt/libvirt.h.in: Define virDomainOpenGraphics
* src/driver.h: Define driver for virDomainOpenGraphics
* src/libvirt_public.syms, src/libvirt.c: Entry point for
virDomainOpenGraphics
* src/libvirt_internal.h: VIR_DRV_FEATURE_FD_PASSING
If a disk source gets dropped because it is not accessible,
mgmt application might want to be informed about this. Therefore
we need to emit an event. The event presented in this patch
is however a bit superset of what written above. The reason is simple:
an intention to be easily expanded, e.g. on 'user ejected disk
in guest' events. Therefore, callback gets source string and disk alias
(which should be unique among a domain) and reason (an integer);
This adds support for a libvirt client configuration file
either /etc/libvirt/libvirt.conf for privileged clients,
or $HOME/.libvirt/libvirt.conf for unprivileged clients.
It allows one parameter
uri_aliases = [
"hail=qemu+ssh://root@hail.cloud.example.com/system",
"sleet=qemu+ssh://root@sleet.cloud.example.com/system",
]
Any call to virConnectOpen with a non-NULL URI will first
attempt to match against the uri_aliases list. An application
can disable this by using VIR_CONNECT_NO_ALIASES
* docs/uri.html.in: Document URI aliases
* include/libvirt/libvirt.h.in: Add VIR_CONNECT_NO_ALIASES
* libvirt.spec.in, mingw32-libvirt.spec.in: Add /etc/libvirt/libvirt.conf
* src/Makefile.am: Install default config file
* src/libvirt.c: Add support for URI aliases
* src/remote/remote_driver.c: Don't try to handle URIs
with no scheme and which clearly are not paths
* src/util/conf.c: Don't raise error on virConfFree(NULL)
* src/xen/xen_driver.c: Don't raise error on URIs
with no scheme
The previous API addition allowed traversal up the hierarchy;
this one makes it easier to traverse down the hierarchy.
In the python bindings, virDomainSnapshotNumChildren can be
generated, but virDomainSnapshotListChildrenNames had to copy
from the hand-written example of virDomainSnapshotListNames.
* include/libvirt/libvirt.h.in (virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames): New prototypes.
(VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS): New flag alias.
* src/libvirt.c (virDomainSnapshotNumChildren)
(virDomainSnapshotListChildrenNames): New functions.
* src/libvirt_public.syms: Export them.
* src/driver.h (virDrvDomainSnapshotNumChildren)
(virDrvDomainSnapshotListChildrenNames): New callbacks.
* python/generator.py (skip_impl, nameFixup): Update lists.
* python/libvirt-override-api.xml: Likewise.
* python/libvirt-override.c
(libvirt_virDomainSnapshotListChildrenNames): New wrapper function.
Although reverting to a snapshot is a form of data loss, this is
normally expected. However, there are two cases where additional
surprises (failure to run the reverted state, or a break in
connectivity to the domain) can come into play. Requiring extra
acknowledgment in these cases will make it less likely that
someone can get into an unrecoverable state due to a default revert.
Also create a new error code, so users can distinguish when forcing
would make a difference, rather than having to blindly request force.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_REVERT_FORCE):
New flag.
* src/libvirt.c (virDomainRevertToSnapshot): Document it.
* include/libvirt/virterror.h (VIR_ERR_SNAPSHOT_REVERT_RISKY): New
error value.
* src/util/virterror.c (virErrorMsg): Implement it.
* tools/virsh.c (cmdDomainSnapshotRevert): Add --force to virsh.
* tools/virsh.pod (snapshot-revert): Document it.
Although a client can already obtain a snapshot's parent by
dumping and parsing the xml, then doing a snapshot lookup by
name, it is more efficient to get the parent in one step, which
in turn will make operations that must traverse a snapshot
hierarchy easier to perform.
* include/libvirt/libvirt.h.in (virDomainSnapshotGetParent):
Declare.
* src/libvirt.c (virDomainSnapshotGetParent): New function.
* src/libvirt_public.syms: Export it.
* src/driver.h (virDrvDomainSnapshotGetParent): New callback.
Qemu sends STOP event as part of the shutdown process. Detect such STOP
event and consider shutdown to be reason of emitting such event. That's
the best we can do until qemu provides us the reason directly in STOP
event. This allows us to report shutdown reason for paused state so that
apps can detect domains that failed to finish the shutdown process
(e.g., because qemu is buggy and doesn't exit on SIGTERM or it is
blocked in flushing disk buffers).
These functions access internals of the opaque object, and do
not need any rpc counterpart. It could be argued that we should
have provided these when snapshot objects were first introduced,
since all the other vir*Ptr objects have at least a GetName accessor.
* include/libvirt/libvirt.h.in (virDomainSnapshotGetName)
(virDomainSnapshotGetDomain, virDomainSnapshotGetConnect): Declare.
* src/libvirt.c (virDomainSnapshotGetName)
(virDomainSnapshotGetDomain, virDomainSnapshotGetConnect): New
functions.
* src/libvirt_public.syms: Export them.
Prior to this patch, <domainsnapshot>/<disks> was ignored. This
changes it to be an error unless an explicit disk snapshot is
requested (a future patch may relax things if it turns out to
be useful to have a <disks> specification alongside a system
checkpoint).
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML): Disk
snapshots not supported yet.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML): Likewise.
In order to distinguish disk snapshots from system checkpoints, a
new state value that is only valid for snapshots is helpful.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_LAST): New placeholder.
* src/conf/domain_conf.h (virDomainSnapshotState): New enum mapping.
(VIR_DOMAIN_DISK_SNAPSHOT): New internal enum value.
* src/conf/domain_conf.c (virDomainState): Use placeholder.
(virDomainSnapshotState): Extend mapping by one for use in snapshot.
(virDomainSnapshotDefParseString, virDomainSnapshotDefFormat):
Handle new state.
(virDomainObjSetState, virDomainStateReasonToString)
(virDomainStateReasonFromString): Avoid compiler warnings.
* tools/virsh.c (vshDomainState, vshDomainStateReasonToString):
Likewise.
* src/libvirt_private.syms (domain_conf.h): Export new functions.
* docs/schemas/domainsnapshot.rng: Tighten state definition.
* docs/formatsnapshot.html.in: Document it.
* tests/domainsnapshotxml2xmlout/disk_snapshot.xml: New test.
Since a snapshot is fully recoverable, it is useful to have a
snapshot as a means of hibernating a guest, then reverting to
the snapshot to wake the guest up. This mode of usage is
similar to 'virsh save/virsh restore', except that virsh
save uses an external file while virsh snapshot keeps the
vm state internal to a qcow2 file. However, it only works on
persistent domains.
In the usage pattern of snapshot/revert for hibernating a guest,
there is no need to keep the guest running between the two points
in time, especially since that would generate runtime state that
would just be discarded. Add a flag to make it possible to
stop the domain after the snapshot has completed.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_CREATE_HALT):
New flag.
* src/libvirt.c (virDomainSnapshotCreateXML): Document it.
* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateXML)
(qemuDomainSnapshotCreateActive): Implement it.
Reverting to a state prior to an external snapshot risks
corrupting any other branches in the snapshot hierarchy that
were using the snapshot as a read-only backing file. So
disk snapshot code will default to preventing reverting to
a snapshot that has any children, meaning that deleting just
the children of a snapshot becomes a useful operation in
preparing that snapshot for being a future reversion target.
The code for the new flag is simple - it's one less deletion,
plus a tweak to keep the current snapshot correct.
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotDelete): Document it, and
enforce mutual exclusion.
* src/qemu/qemu_driver.c (qemuDomainSnapshotDelete): Implement
it.
Just as leaving managed save metadata behind can cause problems
when creating a new domain that happens to collide with the name
of the just-deleted domain, the same is true of leaving any
snapshot metadata behind. For safety sake, extend the semantic
change of commit b26a9fa9 to also cover snapshot metadata as a
reason to reject undefining an inactive domain. A future patch
will make sure that shutdown of a transient domain automatically
deletes snapshot metadata (whether by destroy, shutdown, or
guest-initiated action). Management apps of transient domains
should take care to capture xml of snapshots, if it is necessary
to recreate the snapshot metadata on a later transient domain
with the same name and uuid.
This also documents a new flag that hypervisors can choose to
support as a shortcut for taking care of the metadata as part of
the undefine process; however, nontrivial driver support for these
flags will be deferred to future patches.
Note that ESX and VBox can never be transient; therefore, they
do not have to worry about automatic cleanup after shutdown
(the persistent domain still remains); likewise they never
store snapshot metadata, so the undefine flag is trivial.
The nontrivial work remaining is thus in the qemu driver.
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_UNDEFINE_SNAPSHOTS_METADATA): New flag.
* src/libvirt.c (virDomainUndefine, virDomainUndefineFlags):
Document new limitations and flag.
* src/esx/esx_driver.c (esxDomainUndefineFlags): Trivial
implementation.
* src/vbox/vbox_tmpl.c (vboxDomainUndefineFlags): Likewise.
* src/qemu/qemu_driver.c (qemuDomainUndefineFlags): Enforce
the limitations.
The first two flags are essential for being able to replicate
snapshot hierarchies across multiple hosts, which will come in
handy for supervised migrations. It also allows a management app
to take a snapshot of a transient domain, save the metadata, stop
the domain, recreate a new transient domain by the same name,
redefine the snapshot, then revert to it.
This is not quite as convenient as leaving the metadata behind
after a domain is no longer around, but doing that has a few
problems: 1. the libvirt API can only delete snapshot metadata
if there is a valid domain handle to use to get to that snapshot
object - if stale data is left behind without a domain, there is
no way to request that the data be cleaned up. 2. creating a new
domain with the same name but different uuid than the older
domain where a snapshot existed cannot use the older snapshot
data; this risks confusing libvirt, and forbidding the stale
data is similar to the recent patch to forbid stale managed save.
The first two flags might be useful on hypervisors with no metadata,
but only for modifying the notion of the current snapshot;
however, I don't know how to do that for ESX or VBox.
The third flag is a convenience option, to combine a creation with
a delete metadata into one step. It is trivial for hypervisors
with no metadata.
The qemu changes will be involved enough to warrant a separate patch.
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE)
(VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT)
(VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA): New flags.
* src/libvirt.c (virDomainSnapshotCreateXML): Document them, and
enforce mutual exclusion.
* src/esx/esx_driver.c (esxDomainSnapshotCreateXML): Trivial
implementation.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotCreateXML): Likewise.
* docs/formatsnapshot.html.in: Document re-creation.
To make it easier to know when undefine will fail because of existing
snapshot metadata, we need to know how many snapshots have metadata.
Also, it is handy to filter the list of snapshots to just those that
have no parents; document that flag now, but implement it in later patches.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SNAPSHOT_LIST_ROOTS)
(VIR_DOMAIN_SNAPSHOT_LIST_METADATA): New flags.
* src/libvirt.c (virDomainSnapshotNum)
(virDomainSnapshotListNames): Document them.
* src/esx/esx_driver.c (esxDomainSnapshotNum)
(esxDomainSnapshotListNames): Implement trivial flag.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotNum)
(vboxDomainSnapshotListNames): Likewise.
* src/qemu/qemu_driver.c (qemuDomainSnapshotNum)
(qemuDomainSnapshotListNames): Likewise.
A future patch will make it impossible to remove a domain if it
would leave behind any libvirt-tracked metadata about snapshots,
since stale metadata interferes with a new domain by the same name.
But requiring snaphot contents to be deleted before removing a
domain is harsh; with qemu, qemu-img can still make use of the
contents after the libvirt domain is gone. Therefore, we need
an option to get rid of libvirt tracking information, but not
the actual contents. For hypervisors that do not track any
metadata in libvirt, the implementation is trivial; all remaining
hypervisors (really, just qemu) will be dealt with separately.
* include/libvirt/libvirt.h.in
(VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY): New flag.
* src/libvirt.c (virDomainSnapshotDelete): Document it.
* src/esx/esx_driver.c (esxDomainSnapshotDelete): Trivially
supported when there is no libvirt metadata.
* src/vbox/vbox_tmpl.c (vboxDomainSnapshotDelete): Likewise.
While it is nice that snapshots and saved images remember whether
the domain was running or paused, sometimes the restoration phase
wants to guarantee a particular state (paused to allow hot-plugging,
or running without needing to call resume). This introduces new
flags to allow the control, and a later patch will implement the
flags for qemu.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_SAVE_RUNNING)
(VIR_DOMAIN_SAVE_PAUSED, VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING)
(VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED): New flags.
* src/libvirt.c (virDomainSaveFlags, virDomainRestoreFlags)
(virDomainManagedSave, virDomainSaveImageDefineXML)
(virDomainRevertToSnapshot): Document their use, and enforce
mutual exclusion.
There are two classes of management apps that track events - one
that only cares about on/off (and only needs to track EVENT_STARTED
and EVENT_STOPPED), and one that cares about paused/running (also
tracks EVENT_SUSPENDED/EVENT_RESUMED). To keep both classes happy,
any transition that can go from inactive to paused must emit two
back-to-back events - one for started and one for suspended (since
later resuming of the domain will only send RESUMED, but the first
class isn't tracking that).
This also fixes a bug where virDomainCreateWithFlags with the
VIR_DOMAIN_START_PAUSED flag failed to start paused when restoring
from a managed save image.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_EVENT_SUSPENDED_RESTORED)
(VIR_DOMAIN_EVENT_SUSPENDED_FROM_SNAPSHOT)
(VIR_DOMAIN_EVENT_RESUMED_FROM_SNAPSHOT): New sub-events.
* src/qemu/qemu_driver.c (qemuDomainRevertToSnapshot): Use them.
(qemuDomainSaveImageStartVM): Likewise, and add parameter.
(qemudDomainCreate, qemuDomainObjStart): Send suspended event when
starting paused.
(qemuDomainObjRestore): Add parameter.
(qemuDomainObjStart, qemuDomainRestoreFlags): Update callers.
* examples/domain-events/events-c/event-test.c
(eventDetailToString): Map new detail strings.
This patch adds the ability to make the filesystem for a filesystem
pool during a pool build.
The patch adds two new flags, no overwrite and overwrite, to control
when mkfs gets executed. By default, the patch preserves the
current behavior, i.e., if no flags are specified, pool build on a
filesystem pool only makes the directory on which the filesystem
will be mounted.
If the no overwrite flag is specified, the target device is checked
to determine if a filesystem of the type specified in the pool is
present. If a filesystem of that type is already present, mkfs is
not executed and the build call returns an error. Otherwise, mkfs
is executed and any data present on the device is overwritten.
If the overwrite flag is specified, mkfs is always executed, and any
existing data on the target device is overwritten unconditionally.
There have been several instances of people having problems with
a broken managed save file, and not aware that they could use
'virsh managedsave-remove dom' to fix things. Making it possible
to do this as part of starting a domain makes the same functionality
easier to find, and one less API call.
* include/libvirt/libvirt.h.in (VIR_DOMAIN_START_FORCE_BOOT): New
flag.
* src/libvirt.c (virDomainCreateWithFlags): Document it.
* src/qemu/qemu_driver.c (qemuDomainObjStart): Alter signature.
(qemuAutostartDomain, qemuDomainStartWithFlags): Update callers.
* tools/virsh.c (cmdStart): Expose it in virsh.
* tools/virsh.pod (start): Document it.
The QEMU 'sendkey' command expects keys to be encoded in the same
way as the RFB extended keycode set. Specifically it wants extended
keys to have the high bit of the first byte set, while the Linux
XT KBD driver codeset uses the low bit of the second byte. To deal
with this we introduce a new keymap 'RFB' and use that in the QEMU
driver
* include/libvirt/libvirt.h.in: Add VIR_KEYCODE_SET_RFB
* src/qemu/qemu_driver.c: Use RFB keycode set instead of XT KBD
* src/util/virkeycode-mapgen.py: Auto-generate the RFB keycode
set from the XT KBD set
* src/util/virkeycode.c: Add RFB keycode entry to table. Add a
verify check on cardinality of the codeOffset table
I went with the shorter license notice used by src/libvirt.c,
rather than spelling out the full LGPLv2+ clause into each of
these files.
* configure.ac: Declare copyright.
* all Makefile.am: Likewise.
Make MIGRATION_OUT use the new helper methods.
This also introduces new protection to migration v3 process: the
migration job is held from Begin to Confirm to avoid changes to a domain
during migration (esp. between Begin and Perform phases). This change is
automatically applied to p2p and tunneled migrations. For normal
migration, this requires support from a client. In other words, if an
old (pre 0.9.4) client starts normal migration of a domain, the domain
will not be protected against changes between Begin and Perform steps.
When an operation started by virDomainBlockPull completes (either with
success or with failure), raise an event to indicate the final status.
This API allow users to avoid polling on virDomainGetBlockJobInfo if
they would prefer to use an event mechanism.
* daemon/remote.c: Dispatch events to client
* include/libvirt/libvirt.h.in: Define event ID and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Extend API to handle the new event
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
for block_stream completion and emit a libvirt block pull event
* src/remote/remote_driver.c: Receive and dispatch events to application
* src/remote/remote_protocol.x: Wire protocol definition for the event
* src/remote_protocol-structs: structure definitions for protocol verification
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c: Watch for BLOCK_STREAM_COMPLETED event
from QEMU monitor
Set up the types for the block pull functions and insert them into the
virDriver structure definition. Symbols are exported in this patch to
prevent
documentation compile failures.
* include/libvirt/libvirt.h.in: new API
* src/driver.h: add the new entry to the driver structure
* python/generator.py: fix compiler errors, the actual python bindings
* are
implemented later
* src/libvirt_public.syms: export symbols
* docs/apibuild.py: Extend 'unsigned long' parameter exception to this
* API
Modifying the xml on either save or restore only gets you so
far - you have to remember to 'virsh dumpxml dom' just prior
to the 'virsh save' in order to have an xml file worth modifying
that won't be rejected due to abi breaks. To make this more
powerful, we need a way to grab the xml embedded within a state
file, and from there, it's not much harder to also support
modifying a state file in-place.
Also, virDomainGetXMLDesc didn't document its flags.
* include/libvirt/libvirt.h.in (virDomainSaveImageGetXMLDesc)
(virDomainSaveImageDefineXML): New prototypes.
* src/libvirt.c (virDomainSaveImageGetXMLDesc)
(virDomainSaveImageDefineXML): New API.
* src/libvirt_public.syms: Export them.
* src/driver.h (virDrvDomainSaveImageGetXMLDesc)
(virDrvDomainSaveImgeDefineXML): New driver callbacks.
VIR_ERR_INVALID_ARG implies that an argument cannot possibly
be correct, given the current state of the API.
VIR_ERR_CONFIG_UNSUPPORTED implies that a configuration is
wrong, but arguments aren't configuration.
VIR_ERR_NO_SUPPORT implies that a function is completely
unimplemented.
But in the case of a function that is partially implemented,
yet the full power of the API is not available for that
driver, none of the above messages make sense. Hence a new
error message, implying that the argument is known to comply
with the current state of the API, and that while the driver
supports aspects of the function, it does not support that
particular use of the argument.
A good use case for this is a driver that supports
virDomainSaveFlags, but not the dxml argument of that API.
It might be feasible to also use this new error for all functions
that check flags, and which accept fewer flags than what is possible
in the public API. But doing so would get complicated, since
neither libvirt.c nor the remote driver may do flag filtering,
and every other driver would have to do a two-part check, first
using virCheckFlags on all public flags (which gives
VIR_ERR_INVALID_ARG for an impossible flag), followed by a
particular mask check for VIR_ERR_ARGUMENT_UNSUPPORTED (for a
possible public flag but unsupported by this driver).
* include/libvirt/virterror.h (VIR_ERR_ARGUMENT_UNSUPPORTED): New
error.
* src/util/virterror.c (virErrorMsg): Give it a message.
Suggested by Daniel P. Berrange.
This introduces new API virDomainDestroyFlags to allow
domain destroying with flags, as the existing API virDomainDestroy
misses flags.
The set of flags is defined in virDomainDestroyFlagsValues enum,
which is currently commented, because it is empty.
Calling this API with no flags set (@flags == 0) is equivalent calling
virDomainDestroy.
In order to choose whether to use O_DIRECT when saving a domain image
to a file, we need a new flag. But virDomainSave was implemented
before our policy of all new APIs having a flag argument. Likewise
for virDomainRestore when restoring from a file.
The new flag name is chosen as CACHE_BYPASS so as not to preclude
a future solution that uses posix_fadvise once the Linux kernel has
a smarter implementation of that interface.
* include/libvirt/libvirt.h.in (virDomainCreateFlags)
(virDomainCoreDumpFlags): Add a flag.
(virDomainSaveFlags, virDomainRestoreFlags): New prototypes.
* src/libvirt.c (virDomainSaveFlags, virDomainRestoreFlags): New API.
* src/libvirt_public.syms: Export them.
* src/driver.h (virDrvDomainSaveFlags, virDrvDomainRestoreFlags):
New driver callbacks.
Add virtkey lib for usage-improvment and keycode translating.
Add 4 internal API for the aim
const char *virKeycodeSetTypeToString(int codeset);
int virKeycodeSetTypeFromString(const char *name);
int virKeycodeValueFromString(virKeycodeSet codeset, const char *keyname);
int virKeycodeValueTranslate(virKeycodeSet from_codeset,
virKeycodeSet to_offset,
int key_value);
* include/libvirt/libvirt.h.in: extend virKeycodeSet enum
* src/Makefile.am: add new virtkeycode module and rule to generate
virkeymaps.h
* src/util/virkeycode.c src/util/virkeycode.h: new module
* src/util/virkeycode-mapgen.py: python generator for virkeymaps.h
out of keymaps.csv
* src/libvirt_private.syms: extend private symbols for new module
* .gitignore: add generated virkeymaps.h
This introduces a new API virDomainUndefineFlags to control the
domain undefine process, as the existing API virDomainUndefine
doesn't support flags.
Currently only flag VIR_DOMAIN_UNDEFINE_MANAGED_SAVE is supported.
If the domain has a managed save image, including
VIR_DOMAIN_UNDEFINE_MANAGED_SAVE in @flags will also remove that
file, and omitting the flag will cause undefine process to fail.
This patch also changes the behavior of virDomainUndefine, if the
domain has a managed save image, the undefine will be refused.
This patch extends virDomainSetVcpusFlags API to support
VIR_DOMAIN_AFFECT_CURRENT flag.
Now because most APIs accept VIR_DOMAIN_AFFECT_CURRENT flags,
virDomainSetVcpusFlags API should also do.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Introduce a new API in libvirt-qemu.so
virDomainPtr virDomainQemuAttach(virConnectPtr domain,
unsigned long long pid,
unsigned int flags);
This allows libvirtd to attach to an existing, externally
launched QEMU process. This is useful for QEMU developers who
prefer to launch QEMU themselves for debugging/devel reasons,
but still want the benefit of libvirt based tools like
virt-top, virt-viewer, etc
* include/libvirt/libvirt-qemu.h: Define virDomainQemuAttach
* src/driver.h, src/libvirt-qemu.c, src/libvirt_qemu.syms:
Driver glue for virDomainQemuAttach
Most APIs use 'unsigned int flags'; but a few stragglers were using
a signed value. In particular, the vir*GetXMLDesc APIs were
split-brain, with inconsistent choice of types. Although it is
an API break to use 'int' instead of 'unsigned int', it is ABI
compatible (pre-compiled apps will have no difference in behavior),
and generally apps can be recompiled without any issue (only rare
apps that compiled with extremely high warning levels, or which
pass libvirt API around as typed function pointers, would have to
make any code changes to deal with the change).
The migrate APIs use 'unsigned long flags', which can't be changed,
due to ABI constraints.
This patch intentionally touches only the public API, to prove the
claim that most existing code (including driver callbacks and virsh)
still compiles just fine in spite of the type change.
* include/libvirt/libvirt.h.in (virConnectOpenAuth)
(virDomainCoreDump, virDomainGetXMLDesc, virNetworkGetXMLDesc)
(virNWFilterGetXMLDesc): Use unsigned int for flags.
(virDomainHasCurrentSnapshot): Use consistent spelling.
* src/libvirt.c (virConnectOpenAuth, virDomainCoreDump)
(virDomainGetXMLDesc, virNetworkGetXMLDesc)
(virNWFilterGetXMLDesc, do_open): Update accordingly.
We already have a public virDomainPinVcpu, which implies that
Pin and Vcpu are treated as separate words. Unreleased commit
e261987c introduced virDomainGetVcpupinInfo as the first public
API that used Vcpupin, although we had prior internal uses of
that spelling. For consistency, change the spelling to be two
words everywhere, regardless of whether pin comes first or last.
* daemon/remote.c: Treat vcpu and pin as separate words.
* include/libvirt/libvirt.h.in: Likewise.
* src/conf/domain_conf.c: Likewise.
* src/conf/domain_conf.h: Likewise.
* src/driver.h: Likewise.
* src/libvirt.c: Likewise.
* src/libvirt_private.syms: Likewise.
* src/libvirt_public.syms: Likewise.
* src/libxl/libxl_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/xen/xend_internal.c: Likewise.
* tools/virsh.c: Likewise.
* src/remote/remote_protocol.x: Likewise.
* src/remote_protocol-structs: Likewise.
Suggested by Matthias Bolte.
This patch introduces a new libvirt API (virDomainGetVcpupinInfo),
as a counterpart to virDomainPinVcpuFlags.
We can use virDomainGetVcpus API to retrieve CPU affinity information,
but can't use this API against inactive domains (at least in case of KVM),
as it lacks a flags parameter.
The usual thing is to add a new virDomainGetVcpusFlags, but that API name
is already occupied by the counterpart to virDomainGetMaxVcpus, which
has a completely different signature.
The virDomainGetVcpupinInfo is the new API to retrieve CPU affinity
information of active and inactive domains. While the usual convention
is to list an array before its length, this API violates that rule
in order to be more like virDomainGetVcpus (where maxinfo was doing
double-duty as the length of two different arrays).
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
If an application is using libvirt + KVM as a piece of its
internal infrastructure to perform a specific task, it can
be desirable to guarentee the VM dies when the virConnectPtr
disconnects from libvirtd. This ensures the app can't leak
any VMs it was using. Adding VIR_DOMAIN_START_AUTOKILL as
a flag when starting guests enables this to be done.
* include/libvirt/libvirt.h.in: All VIR_DOMAIN_START_AUTOKILL
* src/qemu/qemu_driver.c: Support automatic killing of guests
upon connection close
* tools/virsh.c: Add --autokill flag to 'start' and 'create'
commands
Since we virEventRegisterDefaultImpl is now a public API, callers need
a way to invoke the default registered Handle and Timeout functions. We
already have general functions for these internally, so promote
them to the public API.
v2:
Actually add APIs to libvirt.h
Even though rpc uses 'unsigned int' for the _len parameter that
passes the length of item<length>, the public libvirt APIs all
use 'int' and filter out lengths < 0, except for virDomainSendKey.
* include/libvirt/libvirt.h.in (virDomainSendKey): All other APIs
use int for array length.
* src/libvirt.c (virDomainSendKey): Adjust.
* src/driver.h (virDrvDomainSendKey): Likewise.
* daemon/remote_generator.pl: Likewise.
When an operation started by virDomainBlockPullAll completes (either with
success or with failure), raise an event to indicate the final status. This
allows an API user to avoid polling on virDomainBlockPullInfo if they would
prefer to use the event mechanism.
* daemon/remote.c: Dispatch events to client
* include/libvirt/libvirt.h.in: Define event ID and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Extend API to handle the new event
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
for block_stream completion and emit a libvirt block pull event
* src/remote/remote_driver.c: Receive and dispatch events to application
* src/remote/remote_protocol.x: Wire protocol definition for the event
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c: Watch for BLOCK_STREAM_COMPLETED event
from QEMU monitor
Signed-off-by: Adam Litke <agl@us.ibm.com>
Set up the types for the block pull functions and insert them into the
virDriver structure definition. Symbols are exported in this patch to prevent
documentation compile failures.
* include/libvirt/libvirt.h.in: new API
* src/driver.h: add the new entry to the driver structure
* python/generator.py: fix compiler errors, the actual python bindings are
implemented later
* src/libvirt_public.syms: export symbols
Signed-off-by: Adam Litke <agl@us.ibm.com>
Add public virDomainSendKey() and enum libvirt_keycode_set
for the @codeset.
Python version of virDomainSendKey() has not been implemented yet,
it will be done soon.
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Qemu once supported following memory stats which will returned by
"query_balloon":
stat_put(dict, "actual", actual);
stat_put(dict, "mem_swapped_in", dev->stats[VIRTIO_BALLOON_S_SWAP_IN]);
stat_put(dict, "mem_swapped_out", dev->stats[VIRTIO_BALLOON_S_SWAP_OUT]);
stat_put(dict, "major_page_faults", dev->stats[VIRTIO_BALLOON_S_MAJFLT]);
stat_put(dict, "minor_page_faults", dev->stats[VIRTIO_BALLOON_S_MINFLT]);
stat_put(dict, "free_mem", dev->stats[VIRTIO_BALLOON_S_MEMFREE]);
stat_put(dict, "total_mem", dev->stats[VIRTIO_BALLOON_S_MEMTOT]);
But it later disabled all the stats except "actual" by commit
07b0403dfc2b2ac179ae5b48105096cc2d03375a.
libvirt doesn't parse "actual", so user will always see a empty result
with "virsh dommemstat $domain". Even qemu haven't disabled the stats,
we should support parsing "actual".
This patch deprecates following enums:
VIR_DOMAIN_MEM_CURRENT
VIR_DOMAIN_MEM_LIVE
VIR_DOMAIN_MEM_CONFIG
VIR_DOMAIN_VCPU_LIVE
VIR_DOMAIN_VCPU_CONFIG
VIR_DOMAIN_DEVICE_MODIFY_CURRENT
VIR_DOMAIN_DEVICE_MODIFY_LIVE
VIR_DOMAIN_DEVICE_MODIFY_CONFIG
And modify internal codes to use virDomainModificationImpact.
This commit is safe precisely because there has been no release
for any of the enum values being deleted (they were added post-0.9.1).
After the 0.9.2 release, we can then take advantage of
virDomainModificationImpact in more places.
* include/libvirt/libvirt.h.in (virDomainModificationImpact): New
enum.
(virDomainSchedParameterFlags, virMemoryParamFlags): Delete, since
these were never released, and the new enum works fine here.
* src/libvirt.c (virDomainGetMemoryParameters)
(virDomainSetMemoryParameters)
(virDomainGetSchedulerParametersFlags)
(virDomainSetSchedulerParametersFlags): Update documentation.
* src/qemu/qemu_driver.c (qemuDomainSetMemoryParameters)
(qemuDomainGetMemoryParameters, qemuSetSchedulerParametersFlags)
(qemuSetSchedulerParameters, qemuGetSchedulerParametersFlags)
(qemuGetSchedulerParameters): Adjust clients.
* tools/virsh.c (cmdSchedinfo, cmdMemtune): Likewise.
Based on ideas by Daniel Veillard and Hu Tao.
Define the basic framework lock manager plugins. The
basic plugin API for 3rd parties to implemented is
defined in
src/locking/lock_driver.h
This allows dlopen()able modules for alternative locking
schemes, however, we do not install the header. This
requires lock plugins to be in-tree allowing changing of
the lock manager plugin API in future.
The libvirt code for loading & calling into plugins
is in
src/locking/lock_manager.{c,h}
* include/libvirt/virterror.h, src/util/virterror.c: Add
VIR_FROM_LOCKING
* src/locking/lock_driver.h: API for lock driver plugins
to implement
* src/locking/lock_manager.c, src/locking/lock_manager.h:
Internal API for managing locking
* src/Makefile.am: Add locking code
This introduces a new domain
VIR_DOMAIN_EVENT_ID_CONTROL_ERROR
Which uses the existing generic callback
typedef void (*virConnectDomainEventGenericCallback)(virConnectPtr conn,
virDomainPtr dom,
void *opaque);
This event is intended to be emitted when there is a failure in
some part of the domain virtualization system. Whether the domain
continues to run/exist after the failure is an implementation
detail specific to the hypervisor.
The idea is that with some types of failure, hypervisors may
prefer to leave the domain running in a "degraded" mode of
operation. For example, if something goes wrong with the QEMU
monitor, it is possible to leave the guest OS running quite
happily. The mgmt app will simply loose the ability todo various
tasks. The mgmt app can then choose how/when to deal with the
failure that occured.
* daemon/remote.c: Dispatch of new event
* examples/domain-events/events-c/event-test.c: Demo catch
of event
* include/libvirt/libvirt.h.in: Define event ID and callback
* src/conf/domain_event.c, src/conf/domain_event.h: Internal
event handling
* src/remote/remote_driver.c: Receipt of new event from daemon
* src/remote/remote_protocol.x: Wire protocol for new event
* src/remote_protocol-structs: add new event for checks
If we can choose live or config when setting, then we need to
be able to choose which one we are querying.
Also, make the documentation clear that set must use a non-empty
subset (some of the hypervisors fail if params is NULL).
* include/libvirt/libvirt.h.in
(virDomainGetSchedulerParametersFlags): New prototype.
* src/libvirt.c (virDomainGetSchedulerParametersFlags): Implement
it.
* src/libvirt_public.syms: Export it.
* python/generator.py (skip_impl): Don't auto-generate.
* src/driver.h (virDrvDomainGetSchedulerParametersFlags): New
callback.
Commit 824dcaff was a regression (thankfully unreleased) for any
client code that used 'struct _virSchedParameter' directly rather
than the preferred virSchedParameter typedef. Adding a #define
avoids even that API change, while rearranging the file makes it
clear what the old vs. new API is.
* include/libvirt/libvirt.h.in: Rearrange older names to the
bottom and improve documentation on preferred names.
(virDomainGetSchedulerParameters, virDomainSetSchedulerParameters)
(virDomainSetSchedulerParametersFlags)
(virDomainSetBlkioParameters, virDomainGetBlkioParameters)
(virDomainSetMemoryParameters, virDomainGetMemoryParameters):
Use newer type names.
* python/libvirt-override.c: Adjust code generation to cope.
Suggested by Daniel P. Berrange.
This is the API agreed on in:
https://www.redhat.com/archives/libvir-list/2011-May/msg00026.html
(with a slight name change to use "...begin" rather than
"...start"). This implements transactional changes to the host network
config. When a transaction is begun with ncf_change_begin(), all other
netcf APIs will continue to work as they always have, but a snapshot
of the existing config will be taken, allowing reversion (rollback,
using ncf_change_rollback()) to the exact state of config at the time
ncf_change_begin() was called. Alternately, if it's determined that
the new changes are acceptable, ncf_change_commit() can be called,
which will eliminate the snapshot and make the changes permanent.
As a failsafe measure, if neither ncf_change_commit() or
ncf_change_rollback() is called by the next time the system reboots,
the netcf-transaction initscript will be automatically called to
rollback the changes.
The new flags allow to pick current state, config or the live
parameter, with current being the existing API default (0).
This also hooks this to --config, --live, --current parameters for
the memtune virsh command
* include/libvirt/libvirt.h.in: defines the new flags
* tools/virsh.c: adds support at virsh level
* tools/virsh.pod: updates virsh documentation
There are two pieces of information which are desirable for
migration, which cannot be supplied by applications
- The explicit QEMU migration URI, while using Peer2Peer
migration
- An override for the target VM XML
This introduces two new public APIs to support these extra
parameters. There is no need for extra wire protocool changes,
since this is supported by the v3 migration enhancements
* include/libvirt/libvirt.h.in,
src/libvirt.c, src/libvirt_public.syms: Add virDomainMigrate2
and virDomainMigrateToURI2
The new type is identical to the three old types that it replaces,
and by creating a common type, this allows future patches to share
common code that manipulates typed parameters.
This change is backwards-compatible in API (recompilation works
without any edits) and ABI (an older client that has not been
recompiled uses the same layout) for code using only public
names; only code using private names (those beginning with _)
will have to adapt.
* include/libvirt/libvirt.h.in (virTypedParameterType)
(VIR_TYPED_PARAM_FIELD_LENGTH, _virTypedParameter): New enum,
macro, and type.
(virSchedParameter, virBlkioParameter, virMemoryParameter):
Rewrite in terms of a common type, while keeping all old public
names for backwards compatibility.
(struct _virSchedParameter, struct _virBlkioParameter)
(struct _virMemoryParameter): Delete - these are private names.
* python/generator.py (enum): Cope with the refactoring.
Add public API for taking screenshots of current domain console.
* include/libvirt/libvirt.h.in: add virDomainScreenshot
* src/libvirt_public.syms: Export new symbol
This patch introduces VIR_DOMAIN_MEM_CURRENT flag and
modifies virDomainSetMemoryFlags function to support it.
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
New APIs are added allowing streaming of content to/from
storage volumes.
* include/libvirt/libvirt.h.in: Add virStorageVolUpload and
virStorageVolDownload APIs
* src/driver.h, src/libvirt.c, src/libvirt_public.syms: Stub
code for new APIs
* src/storage/storage_driver.c, src/esx/esx_storage_driver.c:
Add dummy entries in driver table for new APIs
The Open Nebula driver has been unmaintained since it was first
introduced. The only commits have been for tree-wide cleanups.
It also has a major design flaw, in that it only knows about guests
that it has created itself, which makes it of very limited use.
Discussions wrt evolution of the VMWare ESX driver, concluded that
it should limit itself to single-node ESX operation and not try to
manage the multi-node architecture of VirtualCenter. Open Nebula
is a cluster like Virtual Center, not a single node system, so
the same reasoning applies.
The DeltaCloud project includes an Open Nebula driver and is a much
better fit architecturally, since it is explicitly targetting the
distributed multihost cluster scenario.
Thus this patch deletes the libvirt Open Nebula driver with the
recommendation that people use DeltaCloud for managing it instead.
* configure.ac: Remove probe for xmlrpc & --with-one arg
* daemon/Makefile.am, daemon/libvirtd.c, src/Makefile.am: Remove
ONE driver build
* src/opennebula/one_client.c, src/opennebula/one_client.h,
src/opennebula/one_conf.c, src/opennebula/one_conf.h,
src/opennebula/one_driver.c, src/opennebula/one_driver.c: Delete
files
* autobuild.sh, libvirt.spec.in, mingw32-libvirt.spec.in: Remove
build rules for Open Nebula
* docs/drivers.html.in, docs/sitemap.html.in: Remove reference
to OpenNebula
* docs/drvone.html.in: Delete file
It is possible to set a migration speed limit when starting
migration. This new API allows the speed limit to be changed
on the fly to adjust to changing conditions
* src/driver.h, src/libvirt.c, src/libvirt_public.syms,
include/libvirt/libvirt.h.in: Add virDomainMigrateSetMaxSpeed
* src/esx/esx_driver.c, src/lxc/lxc_driver.c,
src/opennebula/one_driver.c, src/openvz/openvz_driver.c,
src/phyp/phyp_driver.c, src/qemu/qemu_driver.c,
src/remote/remote_driver.c, src/test/test_driver.c,
src/uml/uml_driver.c, src/vbox/vbox_tmpl.c,
src/vmware/vmware_driver.c, src/xen/xen_driver.c,
src/libxl/libxl_driver.c: Stub new API
Add a new xen driver based on libxenlight [1], which is the primary
toolstack starting with Xen 4.1.0. The driver is stateful and runs
privileged only.
Like the existing xen-unified driver, the libxenlight driver is
accessed with xen:// URI. Driver selection is based on the status
of xend. If xend is running, the libxenlight driver will not load
and xen:// connections are handled by xen-unified. If xend is not
running *and* the libxenlight driver is available, xen://
connections are deferred to the libxenlight driver.
V6:
- Address several code style issues noted by Daniel Veillard
- Make drive work with xen:/// URI
- Hold domain object reference while domain is injected in
libvirt event loop. Race found and fixed by Markus Groß.
V5:
- Ensure events are unregistered when domain private data
is destroyed. Discovered and fixed by Markus Groß.
V4:
- Handle restart of libvirtd, reconnecting to previously
started domains
- Rebased to current master
- Tested against Xen 4.1 RC7-pre (c/s 22961:c5d121fd35c0)
V3:
- Reserve vnc port within driver when autoport=yes
V2:
- Update to Xen 4.1 RC6-pre (c/s 22940:5a4710640f81)
- Rebased to current master
- Plug memory leaks found by Stefano Stabellini and valgrind
- Handle SHUTDOWN_crash domain death event
[1] http://lists.xensource.com/archives/html/xen-devel/2009-11/msg00436.html
* Correct the documentation for cgroup: the swap_hard_limit indicates
mem+swap_hard_limit.
* Change cgroup private apis to: virCgroupGet/SetMemSwapHardLimit
Signed-off-by: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
VIR_DOMAIN_MEMORY_PARAM_UNLIMITED uses INT64_MAX but stdint.h
was not and should not be included. Therefore, libvirt.h was
not self-contained.
Instead of including stdint.h specify the value directly.
This patch introduces a new libvirt API (virDomainSetMemoryFlags) and
a flag (virDomainMemoryModFlags).
Signed-off-by: Taku Izumi <izumi.taku@jp.fujitsu.com>
Not all applications have an existing event loop they need
to integrate with. Forcing them to implement the libvirt
event loop integration APIs is an undue burden. This just
exposes our simple poll() based implementation for apps
to use. So instead of calling
virEventRegister(....callbacks...)
The app would call
virEventRegisterDefaultImpl()
And then have a thread somewhere calling
static bool quit = false;
....
while (!quit)
virEventRunDefaultImpl()
* daemon/libvirtd.c, tools/console.c,
tools/virsh.c: Convert to public event loop APIs
* include/libvirt/libvirt.h.in, src/libvirt_private.syms: Add
virEventRegisterDefaultImpl and virEventRunDefaultImpl
* src/util/event.c: Implement virEventRegisterDefaultImpl
and virEventRunDefaultImpl using poll() event loop
* src/util/event_poll.c: Add full error reporting
* src/util/virterror.c, include/libvirt/virterror.h: Add
VIR_FROM_EVENTS
The new virConnectGetSysinfo() API allows one to get the system
information associated to a connection host, providing the same
data as a guest that uses <os><smbios mode='host'/></os>, and in
a format that can be pasted into the guest and edited when using
<os><smbios mode='sysinfo'/></os>.
* include/libvirt/libvirt.h.in (virConnectGetSysinfo): Declare.
* src/libvirt_public.syms: Export new symbol.
Currently users who want to use virDomainQemuMonitorCommand() API or
it's virsh equivalent has to use the same protocol as libvirt uses for
communication to qemu. Since the protocol is QMP with current qemu and
HMP much more usable for humans, one ends up typing something like the
following:
virsh qemu-monitor-command DOM \
'{"execute":"human-monitor-command","arguments":{"command-line":"info kvm"}}'
which is not a very convenient way of debugging qemu.
This patch introduces --hmp option to qemu-monitor-command, which says
that the provided command is in HMP. If libvirt uses QMP to talk with
qemu, the command will automatically be converted into QMP. So the
example above is simplified to just
virsh qemu-monitor-command --hmp DOM "info kvm"
Also the result is converted from
{"return":"kvm support: enabled\r\n"}
to just plain HMP:
kvm support: enabled
If libvirt talks to qemu in HMP, --hmp flag is obviously a noop.
Display or set unlimited values for memory parameters. Unlimited is
represented by INT64_MAX in memory cgroup.
Signed-off-by: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
Reported-by: Justin Clift <jclift@redhat.com>
Fix glitch in commit cddd2a06 (thankfully post-0.8.6, so no
released version has the glitch).
Document and try to workaround glitch in commit 46e9b0f (in 0.8.0),
which invalidated 6 virErrorNumber values dating as far back as 0.7.1.
My audit did not find any other glitches until pre-0.1.0 days. I'm
not sure how to add a syntax-check off the top of my head, but
hopefully the explicit numbering will make people think twice about
renumbering in the future.
* include/libvirt/virterror.h (virErrorDomain): Avoid inserting
new values in the middle, and add explicit numbering to help avoid
this in the future.
(virErrorNumber): Add explicit numbering, and document the snafu.
* src/remote/remote_driver.c (remoteIO): Compensate for the snafu.
The nodeinfo structure includes
nodes : the number of NUMA cell, 1 for uniform mem access
sockets : number of CPU socket per node
cores : number of core per socket
threads : number of threads per core
which does not work well for NUMA topologies where each node does not
consist of integral number of CPU sockets.
We also have VIR_NODEINFO_MAXCPUS macro in public libvirt.h which
computes maximum number of CPUs as (nodes * sockets * cores * threads).
As a result, we can't just change sockets to report total number of
sockets instead of sockets per node. This would probably be the easiest
since I doubt anyone is using the field directly. But because of the
macro, some apps might be using sockets indirectly.
This patch leaves sockets to be the number of CPU sockets per node (and
fixes qemu driver to comply with this) on machines where sockets can be
divided by nodes. If we can't divide sockets by nodes, we behave as if
there was just one NUMA node containing all sockets. Apps interested in
NUMA should consult capabilities XML, which is what they probably do
anyway.
This way, the only case in which apps that care about NUMA may break is
on machines with funky NUMA topology. And there is a chance libvirt
wasn't able to start any guests on those machines anyway (although it
depends on the topology, total number of CPUs and kernel version).
Nothing changes at all for apps that don't care about NUMA.
introduce new public API "virDomainIsUpdated"
* src/conf/domain_conf.h (new member "updated" for "virDomainObj")
* src/libvirt_public.syms
* include/libvirt/libvirt.h.in
To avoid the need for duplicating implementations of virStream
drivers, provide a generic implementation that can handle any
FD based stream. This code is copied from the existing impl
in the QEMU driver, with the locking moved into the stream
impl, and addition of a read callback
The FD stream code will refuse to operate on regular files or
block devices, since those can't report EAGAIN properly when
they would block on I/O
* include/libvirt/virterror.h, include/libvirt/virterror.h: Add
VIR_FROM_STREAM error domain
* src/qemu/qemu_driver.c: Remove code obsoleted by the new
generic streams driver.
* src/fdstream.h, src/fdstream.c, src/fdstream.c,
src/libvirt_private.syms: Generic reusable FD based streams
