Implements functions for both HMP and QMP mode.
For HMP mode, qemu uses "M" as the units by default, so the passed "sized"
is divided by 1024.
For QMP mode, qemu uses "Bytes" as the units by default, the passed "sized"
is multiplied by 1024.
All of the monitor functions return -1 on failure, 0 on success, or -2 if
not supported.
The QEMU monitor command 'add_client' can be used to connect to
a VNC or SPICE graphics display. This allows for implementation
of the virDomainOpenGraphics API
* src/qemu/qemu_driver.c: Implement virDomainOpenGraphics
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Add binding for 'add_client' command
If the daemon is restarted so we reconnect to monitor, cdrom media
can be ejected. In that case we don't want to show it in domain xml,
or require it on migration destination.
To check for disk status use 'info block' monitor command.
This patch adds handlers for modification of guest's interface
link state. Both HMP and QMP commands are supported, but as the
link state functionality is from the beginning supported in QMP
the HMP code will probably never be used.
The mainly changes are:
1) Update qemuMonitorGetBlockStatsInfo and it's children (Text/JSON)
functions to return the value of new latency fields.
2) Add new function qemuMonitorGetBlockStatsParamsNumber, which is
to count how many parameters the underlying QEMU supports.
3) Update virDomainBlockStats in src/qemu/qemu_driver.c to be
compatible with the changes by 1).
No one uses this yet, but it will be important once
virDomainSnapshotCreateXML learns a VIR_DOMAIN_SNAPSHOT_DISK_ONLY
flag, and the xml allows passing in the new file names.
* src/qemu/qemu_monitor.h (qemuMonitorDiskSnapshot): New prototype.
* src/qemu/qemu_monitor_text.h (qemuMonitorTextDiskSnapshot):
Likewise.
* src/qemu/qemu_monitor_json.h (qemuMonitorJSONDiskSnapshot):
Likewise.
* src/qemu/qemu_monitor.c (qemuMonitorDiskSnapshot): New
function.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONDiskSnapshot):
Likewise.
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
The virDomainBlockPull* family of commands are enabled by the
following HMP/QMP commands: 'block_stream', 'block_job_cancel',
'info block-jobs' / 'query-block-jobs', and 'block_job_set_speed'.
* src/qemu/qemu_driver.c src/qemu/qemu_monitor_text.[ch]: implement disk
streaming by using the proper qemu monitor commands.
* src/qemu/qemu_monitor_json.[ch]: implement commands using the qmp monitor
When qemuMonitorCloseFileHandle is called in error path, we need to
preserve the original error since a possible further error when running
closefd monitor command is not very useful to users.
When attaching to an external QEMU process, it is neccessary
to check if the process is using KVM or not. This can be done
using a monitor command
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
API for checking if KVM is enabled
For controlled shutdown we issue a 'system_powerdown' command
to the QEMU monitor. This triggers an ACPI event which (most)
guest OS wire up to a controlled shutdown. There is no equiv
ACPI event to trigger a controlled reboot. This patch attempts
to fake a reboot.
- In qemuDomainObjPrivatePtr we have a bool fakeReboot
flag.
- The virDomainReboot method sets this flag and then
triggers a normal 'system_powerdown'.
- The QEMU process is started with '-no-shutdown'
so that the guest CPUs pause when it powers off the
guest
- When we receive the 'POWEROFF' event from QEMU JSON
monitor if fakeReboot is not set we invoke the
qemuProcessKill command and shutdown continues
normally
- If fakeReboot was set, we spawn a background thread
which issues 'system_reset' to perform a warm reboot
of the guest hardware. Then it issues 'cont' to
start the CPUs again
* src/qemu/qemu_command.c: Add -no-shutdown flag if
we have JSON support
* src/qemu/qemu_domain.h: Add 'fakeReboot' flag to
qemuDomainObjPrivate struct
* src/qemu/qemu_driver.c: Fake reboot using the
system_powerdown command if JSON support is available
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
binding for system_reset command
* src/qemu/qemu_process.c: Reset the guest & start CPUs if
fakeReboot is set
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>
The virDomainBlockPull* family of commands are enabled by the
'block_stream' and 'info block_stream' qemu monitor commands.
* src/qemu/qemu_driver.c src/qemu/qemu_monitor_text.[ch]: implement disk
streaming by using the stream and info stream text monitor commands
* src/qemu/qemu_monitor_json.[ch]: implement commands using the qmp monitor
Signed-off-by: Adam Litke <agl@us.ibm.com>
Acked-by: Daniel P. Berrange <berrange@redhat.com>
Currently the QEMU monitor I/O handler code uses errno values
to report errors. This results in a sub-optimal error messages
on certain conditions, in particular when parsing JSON strings
malformed data simply results in 'EINVAL'.
This changes the code to use the standard libvirt error reporting
APIs. The virError is stored against the qemuMonitorPtr struct,
and when a monitor API is run, any existing stored error is copied
into that thread's error local
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_text.c: Use
virError APIs for all monitor I/O handling code
Currently whenever there is any failure with parsing the monitor,
this is treated in the same was as end-of-file (ie QEMU quit).
The domain is terminated, if not already dead.
With this change, failures in parsing the monitor stream do not
result in the death of QEMU. The guest continues running unchanged,
but all further use of the monitor will be disabled.
The VMM_FAILURE event will be emitted, and the mgmt application
can decide when to kill/restart the guest to re-gain control
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Run a
different callback for monitor EOF vs error conditions.
* src/qemu/qemu_process.c: Emit VMM_FAILURE event when monitor
fails
Use the graphics information from the QEMU migration cookie to
issue a 'client_migrate_info' monitor command to QEMU. This causes
the SPICE client to automatically reconnect to the target host
when migration completes
* src/qemu/qemu_migration.c: Set data for SPICE client relocation
before starting migration on src
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
new qemuMonitorGraphicsRelocate() command
Add the compiler attribute to ensure we don't introduce any more
ref bugs like were just patched in commit 9741f34, then explicitly
mark the remaining places in code that are safe.
* src/qemu/qemu_monitor.h (qemuMonitorUnref): Mark
ATTRIBUTE_RETURN_CHECK.
* src/conf/domain_conf.h (virDomainObjUnref): Likewise.
* src/conf/domain_conf.c (virDomainObjParseXML)
(virDomainLoadStatus): Fix offenders.
* src/openvz/openvz_conf.c (openvzLoadDomains): Likewise.
* src/vmware/vmware_conf.c (vmwareLoadDomains): Likewise.
* src/qemu/qemu_domain.c (qemuDomainObjBeginJob)
(qemuDomainObjBeginJobWithDriver)
(qemuDomainObjExitRemoteWithDriver): Likewise.
* src/qemu/qemu_monitor.c (QEMU_MONITOR_CALLBACK): Likewise.
Suggested by Daniel P. Berrange.
With only a single caller to these two monitor commands, I
didn't need to wrap a new WithFds version, but just change
the command itself.
* src/qemu/qemu_monitor.h (qemuMonitorAddNetdev)
(qemuMonitorAddHostNetwork): Add parameters.
* src/qemu/qemu_monitor.c (qemuMonitorAddNetdev)
(qemuMonitorAddHostNetwork): Add support for fd passing.
* src/qemu/qemu_hotplug.c (qemuDomainAttachNetDevice): Use it to
simplify code.
This is also a bug fix - on the error path, qemu_hotplug would
leave the configfd file leaked into qemu. At least the next
attempt to hotplug a PCI device would reuse the same fdname,
and when the qemu getfd monitor command gets a new fd by the
same name as an earlier one, it closes the earlier one, so there
is no risk of qemu running out of fds.
* src/qemu/qemu_monitor.h (qemuMonitorAddDeviceWithFd): New
prototype.
* src/qemu/qemu_monitor.c (qemuMonitorAddDevice): Move guts...
(qemuMonitorAddDeviceWithFd): ...to new function, and add support
for fd passing.
* src/qemu/qemu_hotplug.c (qemuDomainAttachHostPciDevice): Use it
to simplify code.
Suggested by Daniel P. Berrange.
JSON monitor command implementation can now just directly call text
monitor implementation and it will be automatically encapsulated into
QMP's human-monitor-command.
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.
Currently libvirt doesn't confirm whether the guest has responded to the
disk removal request. In some cases this can leave the guest with
continued access to the device while the mgmt layer believes that it has
been removed. With a recent qemu monitor command[1] we can
deterministically revoke a guests access to the disk (on the QEMU side)
to ensure no futher access is permitted.
This patch adds support for the drive_del() command and introduces it
in the disk removal paths. If the guest is running in a QEMU without this
command we currently explicitly check for unknown command/CommandNotFound
and log the issue.
If QEMU supports the command we issue the drive_del command after we attempt
to remove the device. The guest may respond and remove the block device
before we get to attempt to call drive_del. In that case, we explicitly check
for 'Device not found' from the monitor indicating that the target drive
was auto-deleted upon guest responds to the device removal notification.
1. http://thread.gmane.org/gmane.comp.emulators.qemu/84745
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Currently libvirt doesn't confirm whether the guest has responded to the
disk removal request. In some cases this can leave the guest with
continued access to the device while the mgmt layer believes that it has
been removed. With a recent qemu monitor command[1] we can
deterministically revoke a guests access to the disk (on the QEMU side)
to ensure no futher access is permitted.
This patch adds support for the drive_unplug() command and introduces it
in the disk removal paths. There is some discussion to be had about how
to handle the case where the guest is running in a QEMU without this
command (and the fact that we currently don't have a way of detecting
what monitor commands are available).
Changes since v2:
- use VIR_ERROR to report when unplug command not found
Changes since v1:
- return > 0 when command isn't present, < 0 on command failure
- detect when drive_unplug command isn't present and log error
instead of failing entire command
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
QEMU allows forcing a CDROM eject even if the guest has locked the device.
Expose this via a new UpdateDevice flag, VIR_DOMAIN_DEVICE_MODIFY_FORCE.
This has been requested for RHEV:
https://bugzilla.redhat.com/show_bug.cgi?id=626305
v2: Change flag name, bool cleanups
Older dash mistakenly truncates regular files when using <> redirection;
this kills our use of double dd to reduce storage overhead when
saving qemu images. But qemu insists on running a command through
/bin/sh, so we work around it by having qemu run $sh -c 'real command'
when we have a replacement $sh in mind.
* configure.ac (VIR_WRAPPER_SHELL): Define to a replacement shell,
if /bin/sh is broken on <> redirection.
* src/qemu/qemu_monitor.h (VIR_WRAPPER_SHELL_PREFIX)
(VIR_WRAPPER_SHELL_SUFFIX): New macros.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextMigrateToFile): Use
them.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONMigrateToFile):
Likewise.
Implement the qemu driver's virDomainQemuMonitorCommand
and hook it into the API entry point.
Changes since v1:
- Rename the (external) qemuMonitorCommand to qemuDomainMonitorCommand
- Add virCheckFlags to qemuDomainMonitorCommand
Changes since v2:
- Drop ATTRIBUTE_UNUSED from the flags
Changes since v3:
- Add a flag to priv so we only print out monitor command warning once. Note
that this has not been plumbed into qemuDomainObjPrivateXMLFormat or
qemuDomainObjPrivateXMLParse, which means that if you run a monitor command,
restart libvirtd, and then run another monitor command, you may get an
an erroneous VIR_INFO. It's a pretty minor matter, and I didn't think it
warranted the additional code.
- Add BeginJob/EndJob calls around EnterMonitor/ExitMonitor
Signed-off-by: Chris Lalancette <clalance@redhat.com>
The patches for shared storage migration were not correctly written
for json mode. Thus the 'blk' and 'inc' parameters were never being
set. In addition they didn't set the QEMU_MONITOR_MIGRATE_BACKGROUND
so migration was synchronous. Due to multiple bugs in QEMU's JSON
impl this wasn't noticed because it treated the sync migration requst
as asynchronous anyway. Finally 'background' parameter was converted
to take arbitrary flags but not renamed, and not all uses were changed
to unsigned int.
* src/qemu/qemu_driver.c: Set QEMU_MONITOR_MIGRATE_BACKGROUND in
doNativeMigrate
* src/qemu/qemu_monitor_json.c: Process QEMU_MONITOR_MIGRATE_NON_SHARED_DISK
and QEMU_MONITOR_MIGRATE_NON_SHARED_INC flags
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.h, src/qemu/qemu_monitor_text.c,
src/qemu/qemu_monitor_text.h: change 'int background' to
'unsigned int flags' in migration APIs. Add logging of flags
parameter
The current code pattern requires that callers of qemuMonitorClose
check for the return value == 0, and if so, set priv->mon = NULL
and release the reference held on the associated virDomainObjPtr
The change d84bb6d6a3 violated that
requirement, meaning that priv->mon never gets set to NULL, and
a reference count is leaked on virDomainObjPtr.
This design was a bad one, so remove the need to check the return
valueof qemuMonitorClose(). Instead allow registration of a
callback that's invoked just when the last reference on qemuMonitorPtr
is released.
Finally there was a potential reference leak in qemuConnectMonitor
in the failure path.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add a destroy
callback invoked from qemuMonitorFree
* src/qemu/qemu_driver.c: Use the destroy callback to release the
reference on virDomainObjPtr when the monitor is freed. Fix other
potential reference count leak in connecting to monitor
Followup to https://bugzilla.redhat.com/show_bug.cgi?id=599091,
commit 20206a4b, to reduce disk waste in padding.
* src/qemu/qemu_monitor.h (QEMU_MONITOR_MIGRATE_TO_FILE_BS): Drop
back to 4k.
(QEMU_MONITOR_MIGRATE_TO_FILE_TRANSFER_SIZE): New macro.
* src/qemu/qemu_driver.c (qemudDomainSaveFlag): Update comment.
* src/qemu/qemu_monitor_text.c (qemuMonitorTextMigrateToFile): Use
two invocations of dd to output non-aligned large blocks.
* src/qemu/qemu_monitor_json.c (qemuMonitorJSONMigrateToFile):
Likewise.
See https://bugzilla.redhat.com/show_bug.cgi?id=599091
Saving a paused 512MB domain took 3m47s with the old block size of 512
bytes. Changing the block size to 1024*1024 decreased the time to 56
seconds. (Doubling again to 2048*1024 yielded 0 improvement; lowering
to 512k increased the save time to 1m10s, about 20%)
The virDomainGetBlockInfo API allows query physical block
extent and allocated block extent. These are normally the
same value unless storing a special format like qcow2
inside a block device. In this scenario we can query QEMU
to get the actual allocated extent.
Since last time:
- Return fatal error in text monitor
- Only invoke monitor command for block devices
- Fix error handling JSON code
* src/qemu/qemu_driver.c: Fill in block aloction extent when VM
is running
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
API to query the highest block extent via info blockstats
QEMU is gaining a new monitor command netdev_add for hotplugging
NICs using the netdev backend code. We already support this on
the command this, though it is disabled. This adds support for
hotplug too, also to remain disabled until 0.13 QEMU is released
* src/qemu/qemu_driver.c: Support netdev hotplug for NICs
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Add
support for netdev_add and netdev_remove commands
Support for live migration between hosts that do not share storage was
added to qemu-kvm release 0.12.1.
It supports two flags:
-b migration without shared storage with full disk copy
-i migration without shared storage with incremental copy (same base image
shared between source and destination).
I tested the live migration without shared storage (both flags) for native
and p2p with and without tunnelling. I also verified that the fix doesn't
affect normal migration with shared storage.
This introduces a new event type
VIR_DOMAIN_EVENT_ID_IO_ERROR_REASON
This event is the same as the previous VIR_DOMAIN_ID_IO_ERROR
event, but also includes a string describing the cause of
the event.
Thus there is a new callback definition for this event type
typedef void (*virConnectDomainEventIOErrorReasonCallback)(virConnectPtr conn,
virDomainPtr dom,
const char *srcPath,
const char *devAlias,
int action,
const char *reason,
void *opaque);
This is currently wired up to the QEMU block IO error events
* daemon/remote.c: Dispatch IO error events to client
* examples/domain-events/events-c/event-test.c: Watch for
IO error events
* include/libvirt/libvirt.h.in: Define new IO error event ID
and callback signature
* src/conf/domain_event.c, src/conf/domain_event.h,
src/libvirt_private.syms: Extend API to handle IO error events
* src/qemu/qemu_driver.c: Connect to the QEMU monitor event
for block IO errors and emit a libvirt IO error event
* src/remote/remote_driver.c: Receive and dispatch IO error
events to application
* src/remote/remote_protocol.x: Wire protocol definition for
IO error events
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c: Watch for BLOCK_IO_ERROR event
from QEMU monitor
The save process was relying on use of the shell >> append
operator to ensure the save data was placed after the libvirt
header + XML. This doesn't work for block devices though.
Replace this code with use of 'dd' and its 'seek' parameter.
This means that we need to pad the header + XML out to a
multiple of dd block size (in this case we choose 512).
The qemuMonitorMigateToCommand() monitor API is used for both
save/coredump, and migration via UNIX socket. We can't simply
switch this to use 'dd' since this causes problems with the
migration usage. Thus, create a dedicated qemuMonitorMigateToFile
which can accept an filename + offset, and remove the filename
from the current qemuMonitorMigateToCommand() API
* src/qemu/qemu_driver.c: Switch to qemuMonitorMigateToFile
for save and core dump
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h,
src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h: Create
a new qemuMonitorMigateToFile, separate from the existing
qemuMonitorMigateToCommand to allow handling file offsets
