The way QEMU is started has been changed to use '-device' and
the new style '-drive' syntax. This needs to be mirrored in
the hotplug code, requiring addition of two new APIs.
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Define APIs
qemuMonitorAddDevice() and qemuMonitorAddDrive()
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Implement the new monitor APIs
* src/util/json.c, src/util/json.h: Declare returned strings
to be const
* src/qemu/qemu_monitor.c: Wire up JSON mode for qemuMonitorGetPtyPaths
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h: Fix
const correctness. Add missing error message in the function
qemuMonitorJSONGetAllPCIAddresses. Add implementation of the
qemuMonitorGetPtyPaths function calling 'query-chardev'.
Hotunplug of devices requires that we know their PCI address. Even
hotplug of SCSI drives, required that we know the PCI address of
the SCSI controller to attach the drive to. We can find this out
by running 'info pci' and then correlating the vendor/product IDs
with the devices we booted with.
Although this approach is somewhat fragile, it is the only viable
option with QEMU < 0.12, since there is no way for libvirto set
explicit PCI addresses when creating devices in the first place.
For QEMU > 0.12, this code will not be used.
* src/qemu/qemu_driver.c: Assign all dynamic PCI addresses on
startup of QEMU VM, matching vendor/product IDs
* 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 fetching PCI device address mapping
The current SCSI hotplug support attaches a brand new SCSI controller
for every disk. This is broken because the semantics differ from those
used when starting the VM initially. In the latter case, each SCSI
controller is filled before a new one is added.
If the user specifies an high drive index (sdazz) then at initial
startup, many intermediate SCSI controllers may be added with no
drives.
This patch changes SCSI hotplug so that it exactly matches the
behaviour of initial startup. First the SCSI controller number is
determined for the drive to be hotplugged. If any controller upto
and including that controller number is not yet present, it is
attached. Then finally the drive is attached to the last controller.
NB, this breaks SCSI hotunplug, because there is no 'drive_del'
command in current QEMU. Previous SCSI hotunplug was broken in
any case because it was unplugging the entire controller, not
just the drive in question.
A future QEMU will allow proper SCSI hotunplug of a drive.
This patch is derived from work done by Wolfgang Mauerer on disk
controllers.
* src/qemu/qemu_driver.c: Fix SCSI hotplug to add a drive to
the correct controller, instead of just attaching a new
controller.
* 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 'drive_add' command
This patch allows for explicit hotplug/unplug of SCSI controllers.
Ordinarily this is not required, since QEMU/libvirt will attach
a new SCSI controller whenever one is required. Allowing explicit
hotplug of controllers though, enables the caller to specify a
static PCI address, instead of auto-assigning the next available
PCI slot. Or it will when we have static PCI addressing.
This patch is derived from Wolfgang Mauerer's disk controller
patch series.
* src/qemu/qemu_driver.c: Support hotplug & unplug of SCSI
controllers
* 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 API for attaching PCI SCSI controllers
Convert the QEMU monitor APIs over to use virDomainDeviceAddress
structs for passing addresses in/out, instead of individual bits.
This makes the number of parameters smaller & easier to deal with.
No functional change
* src/qemu/qemu_driver.c, src/qemu/qemu_monitor.c,
src/qemu/qemu_monitor.h, src/qemu/qemu_monitor_text.c,
src/qemu/qemu_monitor_text.h: Change monitor hotplug APIs to
take an explicit address ptr for all host/guest addresses
This change makes the QEMU driver get pty paths from the output of the
monitor 'info chardev' command. This output is structured, and contains
both the name of the device and the path on the same line. This is
considerably more reliable than parsing the startup log output, which
requires the parsing code to know which order QEMU will print pty
information in.
Note that we still need to parse the log output as the monitor itself
may be on a pty. This should be rare, however, and the new code will
replace all pty paths parsed by the log output method once the monitor
is available.
* src/qemu/qemu_monitor.(c|h) src/qemu_monitor_text.(c|h): Implement
qemuMonitorGetPtyPaths().
* src/qemu/qemu_driver.c: Get pty path information using
qemuMonitorGetPtyPaths().
The QEMU 0.10.0 release (and possibly other 0.10.x) has a bug where
it sometimes/often forgets to display the initial monitor greeting
line, soley printing a (qemu). This in turn confuses the text
console parsing because it has a '(qemu)' it is not expecting. The
confusion results in a negative malloc. Bad things follow.
This re-writes the text console handling to be more robust. The key
idea is that it should only look for a (qemu), once it has seen the
original command echo'd back. This ensures it'll skip the bogus stray
(qemu) with broken QEMUs.
* src/qemu/qemu_monitor.c: Add some (disabled) debug code
* src/qemu/qemu_monitor_text.c: Re-write way command replies
are detected
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add callbacks
for reset, shutdown, poweroff and stop events. Add convenience
methods for emiting those events
With addition of events there will be alot of callbacks.
To avoid having to add many APIs to register callbacks,
provide them all at once in a big table
* src/qemu/qemu_driver.c: Pass in a callback table to QEMU
monitor code
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h Replace
the EOF and disk secret callbacks with a callback table
Initial support for the new QEMU monitor protocol using JSON
as the data encoding format instead of plain text
* po/POTFILES.in: Add src/qemu/qemu_monitor_json.c
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Hack to turn on QMP
mode. Replace with a version number check on >= 0.12 later
* src/qemu/qemu_monitor.c: Delegate to json monitor if enabled
* src/qemu/qemu_monitor_json.c, src/qemu/qemu_monitor_json.h: Add
impl of QMP protocol
* src/Makefile.am: Add src/qemu/qemu_monitor_json.{c,h}
Now that drivers are using a private domain object state blob,
the virDomainObjFormat/Parse methods are no longer able to
directly serialize all neccessary state to/from XML. It is
thus neccessary to introduce a pair of callbacks fo serializing
private state.
The code for serializing vCPU PIDs and the monitor device
config can now move out of domain_conf.c and into the
qemu_driver.c where they belong.
* src/conf/capabilities.h: Add callbacks for serializing private
state to/from XML
* src/conf/domain_conf.c, src/conf/domain_conf.h: Remove the
monitor, monitor_chr, monitorWatch, nvcpupids and vcpupids
fields from virDomainObjPtr. Remove code that serialized
those fields
* src/libvirt_private.syms: Export virXPathBoolean
* src/qemu/qemu_driver.c: Add callbacks for serializing monitor
and vcpupid data to/from XML
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Pass monitor
char device config into qemuMonitorOpen directly.
The current QEMU disk media change does not support setting the
disk format. The new JSON monitor will support this, so add an
extra parameter to pass this info in
* src/qemu/qemu_driver.c: Pass in disk format when changing media
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c,
src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Add a 'format' arg to qemuMonitorChangeMedia()
The qemuMonitorEscape() method, and the VIR_ENUM for migration
status will be needed by the JSON monitor too, so move that code
into the shared qemu_monitor.c file instead of qemu_monitor_text.c
* src/qemu/qemu_monitor.h: Declare qemuMonitorMigrationStatus enum
and qemuMonitorEscapeArg and qemuMonitorEscapeShell methods
* src/qemu/qemu_monitor.c: Implement qemuMonitorMigrationStatus enum
and qemuMonitorEscapeArg and qemuMonitorEscapeShell methods
* src/qemu/qemu_monitor_text.c: Remove above methods/enum
If QEMU shuts down while we're in the middle of processing a
monitor command, the monitor will be freed, and upon cleaning
up we attempt to do qemuMonitorUnlock(priv->mon) when priv->mon
is NULL.
To address this we introduce proper reference counting into
the qemuMonitorPtr object, and hold an extra reference whenever
executing a command.
* src/qemu/qemu_driver.c: Hold a reference on the monitor while
executing commands, and only NULL-ify the priv->mon field when
the last reference is released
* src/qemu/qemu_monitor.h, src/qemu/qemu_monitor.c: Add reference
counting to handle safe deletion of monitor objects
The QEMU monitor open method would not take a reference on
the virDomainObjPtr until it had successfully opened the
monitor. The cleanup code upon failure to open though would
call qemuMonitorClose() which would in turn decrement the
reference count. This caused the virDoaminObjPtr to be mistakenly
freed and then the whole driver crashes
* src/qemu/qemu_monitor.c: Fix reference counting in
qemuMonitorOpen
Change the QEMU monitor file handle watch to poll for both
read & write events, as well as EOF. All I/O to/from the
QEMU monitor FD is now done in the event callback thread.
When the QEMU driver needs to send a command, it puts the
data to be sent into a qemuMonitorMessagePtr object instance,
queues it for dispatch, and then goes to sleep on a condition
variable. The event thread sends all the data, and then waits
for the reply to arrive, putting the response / error data
back into the qemuMonitorMessagePtr and notifying the condition
variable.
There is a temporary hack in the disk passphrase callback to
avoid acquiring the domain lock. This avoids a deadlock in
the command processing, since the domain lock is still held
when running monitor commands. The next commit will remove
the locking when running commands & thus allow re-introduction
of locking the disk passphrase callback
* src/qemu/qemu_driver.c: Temporarily don't acquire lock in
disk passphrase callback. To be reverted in next commit
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Remove
raw I/O functions, and a generic qemuMonitorSend() for
invoking a command
* src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Remove all low level I/O, and use the new qemuMonitorSend()
API. Provide a qemuMonitorTextIOProcess() method for detecting
command/reply/prompt boundaries in the monitor data stream
In preparation of the monitor I/O process becoming fully asynchronous,
it is neccessary to ensure all access to internals of the qemuMonitorPtr
object is protected by a mutex lock.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add mutex for locking
monitor.
* src/qemu/qemu_driver.c: Add locking around all monitor commands
Change the QEMU driver to not directly invoke the text mode monitor
APIs. Instead add a generic wrapper layer, which will eventually
invoke either the text or JSON protocol code as needed. Pass an
qemuMonitorPtr object into the monitor APIs instead of virDomainObjPtr
to complete the de-coupling of the monitor impl from virDomainObj
data structures
* src/qemu/qemu_conf.h: Remove qemuDomainObjPrivate definition
* src/qemu/qemu_driver.c: Add qemuDomainObjPrivate definition.
Pass qemuMonitorPtr into all monitor APIs instead of the
virDomainObjPtr instance.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Add thin
wrappers for all qemuMonitorXXX command APIs, calling into
qemu_monitor_text.c/h
* src/qemu/qemu_monitor_text.c, src/qemu/qemu_monitor_text.h:
Rename qemuMonitor -> qemuMonitorText & update to accept
qemuMonitorPtr instead of virDomainObjPtr
Decouple the monitor code from the virDomainDefPtr structure
by moving the disk encryption lookup code back into the
qemu_driver.c file. Instead provide a function callback to
the monitor code which can be invoked to retrieve encryption
data as required.
* src/qemu/qemu_driver.c: Add findDomainDiskEncryption,
and findVolumeQcowPassphrase. Pass address of the method
findVolumeQcowPassphrase into qemuMonitorOpen()
* src/qemu/qemu_monitor.c: Associate a disk
encryption function callback with the qemuMonitorPtr
object.
* src/qemu/qemu_monitor_text.c: Remove findDomainDiskEncryption
and findVolumeQcowPassphrase.
Introduce a new qemuDomainObjPrivate object which is used to store
the private QEMU specific data associated with each virDomainObjPtr
instance. This contains a single member, an instance of the new
qemuMonitorPtr object which encapsulates the QEMU monitor state.
The internals of the latter are private to the qemu_monitor* files,
not to be shown to qemu_driver.c
* src/qemu/qemu_conf.h: Definition of qemuDomainObjPrivate.
* src/qemu/qemu_driver.c: Register a functions for creating
and freeing qemuDomainObjPrivate instances with the domain
capabilities. Remove the qemudDispatchVMEvent() watch since
I/O watches are now handled by the monitor code itself. Pass
a new qemuHandleMonitorEOF() callback into qemuMonitorOpen
to allow notification when the monitor quits.
* src/qemu/qemu_monitor.c, src/qemu/qemu_monitor.h: Introduce
the 'qemuMonitor' object. Temporarily add new APIs
qemuMonitorWrite, qemuMonitorRead, qemuMonitorWaitForInput
to allow text based monitor impl to perform I/O.
* src/qemu/qemu_monitor_text.c: Call APIs for reading/writing
to monitor instead of accessing the file handle directly.
The qemu_driver.c code should not contain any code that interacts
with the QEMU monitor at a low level. A previous commit moved all
the command invocations out. This change moves out the code which
actually opens the monitor device.
* src/qemu/qemu_driver.c: Remove qemudOpenMonitor & methods called
from it.
* src/Makefile.am: Add qemu_monitor.{c,h}
* src/qemu/qemu_monitor.h: Add qemuMonitorOpen()
* src/qemu/qemu_monitor.c: All code for opening the monitor
