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This introduces a new running reason VIR_DOMAIN_RUNNING_WAKEUP,
and new suspend event type VIR_DOMAIN_EVENT_STARTED_WAKEUP.
While a wakeup event is emitted, the domain which entered into
VIR_DOMAIN_PMSUSPENDED will be transferred to "running"
with reason VIR_DOMAIN_RUNNING_WAKEUP, and a new domain lifecycle
event emitted with type VIR_DOMAIN_EVENT_STARTED_WAKEUP.
This introduces a new domain state pmsuspended to represent
the domain which has been suspended by guest power management,
e.g. (entered itno s3 state). Because a "running" state could
be confused in this case, one will see the guest is paused
actually while playing. And state "paused" is for the domain
which was paused by virDomainSuspend.
This patch introduces a new event type for the QMP event
SUSPEND:
VIR_DOMAIN_EVENT_ID_PMSUSPEND
The event doesn't take any data, but considering there might
be reason for wakeup in future, the callback definition is:
typedef void
(*virConnectDomainEventSuspendCallback)(virConnectPtr conn,
virDomainPtr dom,
int reason,
void *opaque);
"reason" is unused currently, always passes "0".
This patch introduces a new event type for the QMP event
WAKEUP:
VIR_DOMAIN_EVENT_ID_PMWAKEUP
The event doesn't take any data, but considering there might
be reason for wakeup in future, the callback definition is:
typedef void
(*virConnectDomainEventWakeupCallback)(virConnectPtr conn,
virDomainPtr dom,
int reason,
void *opaque);
"reason" is unused currently, always passes "0".
This patch introduces a new event type for the QMP event
DEVICE_TRAY_MOVED, which occurs when the tray of a removable
disk is moved (i.e opened or closed):
VIR_DOMAIN_EVENT_ID_TRAY_CHANGE
The event's data includes the device alias and the reason
for tray status' changing, which indicates why the tray
status was changed. Thus the callback definition for the event
is:
enum {
VIR_DOMAIN_EVENT_TRAY_CHANGE_OPEN = 0,
VIR_DOMAIN_EVENT_TRAY_CHANGE_CLOSE,
\#ifdef VIR_ENUM_SENTINELS
VIR_DOMAIN_EVENT_TRAY_CHANGE_LAST
\#endif
} virDomainEventTrayChangeReason;
typedef void
(*virConnectDomainEventTrayChangeCallback)(virConnectPtr conn,
virDomainPtr dom,
const char *devAlias,
int reason,
void *opaque);
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>