Commit Graph

439 Commits

Author SHA1 Message Date
Stefan Berger
c2b38277b3 802.1Qbg: use pre-associate state at beginning of inc. migr
This patch introduces the usage of the pre-associate state of the IEEE 802.1Qbg standard on incoming VM migration on the target host. It is in response to bugzilla entry 632750.

https://bugzilla.redhat.com/show_bug.cgi?id=632750

For being able to differentiate the exact reason as to why a macvtap device is being created, either due to a VM creation or an incoming VM migration, I needed to pass that reason as a parameter from wherever qemudStartVMDaemon is being called in order to determine whether to send an ASSOCIATE (VM creation) or a PRE-ASSOCIATE (incoming VM migration) towards lldpad.

I am also fixing a problem with the virsh domainxml-to-native call on the way.

Gerhard successfully tested the patch with a recent blade network 802.1Qbg-compliant switch.

The patch should not have any side-effects on the 802.1Qbh support in libvirt, but Roopa (cc'ed) may want to verify this.
2010-11-30 12:50:54 -05:00
Osier Yang
c1fb916618 implement callback function for qemu driver
* src/qemu/qemu_driver.c (add function qemuDomainIsUpdated)
2010-11-23 15:04:42 -07:00
Osier Yang
37a02efd71 define internal driver API
* src/driver.h (new typedef, new callback member for "_virDriver")
* 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/xen/xen_driver.c
* src/xenapi/xenapi_driver.c
2010-11-23 15:04:41 -07:00
Daniel P. Berrange
7f9cebc0c0 Ensure logfile isn't truncated by shutdown message.
When running non-root, the QEMU log file is usually opened with
truncation, since there is no logrotate for non-root usage.
This means that when libvirt logs the shutdown timestamp, the
log is accidentally truncated

* src/qemu/qemu_driver.c: Never truncate log file with shutdown
  message
2010-11-23 14:10:05 +00:00
Cole Robinson
388fa6257e qemu: setvcpus: Save config changes to disk
Currently changes to the persistent config aren't flushed to disk, meaning
they are lost if the domain is redefined or libvirtd is restarted.
2010-11-23 08:42:46 -05:00
Cole Robinson
39b6265476 qemu: setvcpus: Simplify altering the persistent config
Do this by adding a helper function to get the persistent domain config. This
should be useful for other functions that may eventually want to alter
the persistent domain config (attach/detach device). Also make similar changes
to the test drivers setvcpus command.

A caveat is that the function will return the running config for a transient
domain, rather than error. This simplifies callers, as long as they use
other methods to ensure the guest is persistent.
2010-11-23 08:42:46 -05:00
Cole Robinson
d75202915e qemu: setvcpus: Fix maxvcpus check
Doing 'virsh setvcpus $vm --config 10' doesn't check the value against the
domains maxvcpus value. A larger value for example will prevent the guest
from starting.

Also make a similar change to the test driver.
2010-11-23 08:42:46 -05:00
Cole Robinson
45ec297d6f Make state driver device hotplug/update actually transient
The current semantics of non-persistent hotplug/update are confusing: the
changes will persist as long as the in memory domain definition isn't
overwritten. This means hotplug changes stay around until the domain is
redefined or libvirtd is restarted.

Call virDomainObjSetDefTransient at VM startup, so that we properly discard
hotplug changes when the VM is shutdown.
2010-11-23 08:42:45 -05:00
Eric Blake
0d5f54bb21 maint: use gnulib configmake rather than open-coding things
* bootstrap.conf (gnulib_modules): Add configmake.
* daemon/Makefile.am (libvirtd_CFLAGS): Drop defines provided by
gnulib.
* src/Makefile.am (INCLUDES): Likewise.
* tests/Makefile.am (INCLUDES): Likewise.
* tools/Makefile.am (virsh_CFLAGS): Likewise.
* daemon/libvirtd.c (qemudInitPaths, usage, main): Update
clients.
* src/cpu/cpu_map.c (CPUMAPFILE): Likewise.
* src/driver.c (DEFAULT_DRIVER_DIR): Likewise.
* src/internal.h (_): Likewise.
* src/libvirt.c (virInitialize): Likewise.
* src/lxc/lxc_conf.h (LXC_CONFIG_DIR, LXC_STATE_DIR, LXC_LOG_DIR):
Likewise.
* src/lxc/lxc_conf.c (lxcCapsInit, lxcLoadDriverConfig):
Likewise.
* src/network/bridge_driver.c (NETWORK_PID_DIR)
(NETWORK_STATE_DIR, DNSMASQ_STATE_DIR, networkStartup): Likewise.
* src/nwfilter/nwfilter_driver.c (nwfilterDriverStartup):
Likewise.
* src/qemu/qemu_conf.c (qemudLoadDriverConfig): Likewise.
* src/qemu/qemu_driver.c (qemudStartup): Likewise.
* src/remote/remote_driver.h (LIBVIRTD_PRIV_UNIX_SOCKET)
(LIBVIRTD_PRIV_UNIX_SOCKET_RO, LIBVIRTD_CONFIGURATION_FILE)
(LIBVIRT_PKI_DIR): Likewise.
* src/secret/secret_driver.c (secretDriverStartup): Likewise.
* src/security/security_apparmor.c (VIRT_AA_HELPER): Likewise.
* src/security/virt-aa-helper.c (main): Likewise.
* src/storage/storage_backend_disk.c (PARTHELPER): Likewise.
* src/storage/storage_driver.c (storageDriverStartup): Likewise.
* src/uml/uml_driver.c (TEMPDIR, umlStartup): Likewise.
* src/util/hooks.c (LIBVIRT_HOOK_DIR): Likewise.
* tools/virsh.c (main): Likewise.
* docs/hooks.html.in: Likewise.
2010-11-17 08:58:58 -07:00
Stefan Berger
7b7cb1ecc9 deprecate fclose() and introduce VIR_{FORCE_}FCLOSE()
Similarly to deprecating close(), I am now deprecating fclose() and
introduce VIR_FORCE_FCLOSE() and VIR_FCLOSE(). Also, fdopen() is replaced with
VIR_FDOPEN().

Most of the files are opened in read-only mode, so usage of
VIR_FORCE_CLOSE() seemed appropriate. Others that are opened in write
mode already had the fclose()<  0 check and I converted those to
VIR_FCLOSE()<  0.

I did not find occurrences of possible double-closed files on the way.
2010-11-16 21:13:29 -05:00
Osier Yang
93bc093ac2 qemu: record timestamp in qemu domain log
Currently only support domain start and shutdown, for domain start,
record timestamp before the qemu command line, and for domain shutdown,
just say it's shutting down with timestamp.

* src/qemu/qemu_driver.c (qemudStartVMDaemon, qemudShutdownVMDaemon
  introduced two macros - START_POSTFIX, SHUTDOWN_POSTFIX)
2010-11-16 09:18:32 -07:00
Daniel P. Berrange
bdb28f4426 Support virDomainOpenConsole with QEMU
This provides an implementation of the virDomainOpenConsole
API with the QEMU driver. For the streams code, this reuses
most of the code previously added for the tunnelled migration
streams since it is generic.

* src/qemu/qemu_driver.c: Support virDomainOpenConsole
2010-11-11 16:03:03 +00:00
Daniel P. Berrange
7c08fcc439 Add a generic internal API for handling any FD based stream
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
2010-11-11 16:02:57 +00:00
Daniel P. Berrange
88a9b382c6 Introduce a virDomainOpenConsole API
To enable virsh console (or equivalent) to be used remotely
it is necessary to provide remote access to the /dev/pts/XXX
pseudo-TTY associated with the console/serial/parallel device
in the guest. The virStream API provide a bi-directional I/O
stream capability that can be used for this purpose. This
patch thus introduces a virDomainOpenConsole API that uses
the stream APIs.

* src/libvirt.c, src/libvirt_public.syms,
  include/libvirt/libvirt.h.in, src/driver.h: Define the
  new virDomainOpenConsole API
* 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/xen/xen_driver.c, src/xenapi/xenapi_driver.c: Stub
  API entry point
2010-11-11 16:02:41 +00:00
Cole Robinson
96d52fcf43 qemu: Add flag to force a CDROM eject
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
2010-11-10 12:31:20 -05:00
Stefan Berger
60ae1c34ad bye to close(), welcome to VIR_(FORCE_)CLOSE()
Using automated replacement with sed and editing I have now replaced all
occurrences of close() with VIR_(FORCE_)CLOSE() except for one, of
course. Some replacements were straight forward, others I needed to pay
attention. I hope I payed attention in all the right places... Please
have a look. This should have at least solved one more double-close
error.
2010-11-09 15:48:48 -05:00
Daniel P. Berrange
7a696678e5 Define XML syntax for password expiry
This extends the XML syntax for <graphics> to allow a password
expiry time to be set

eg

  <graphics type='vnc' port='5900' autoport='yes' keymap='en-us' passwd='12345' passwdValidTo='2010-04-09T15:51:00'/>

The timestamp is in UTC.

* src/conf/domain_conf.h: Pull passwd out into separate struct
  virDomainGraphicsAuthDef to allow sharing between VNC & SPICE
* src/conf/domain_conf.c: Add parsing/formatting of new passwdValidTo
  argument
* src/opennebula/one_conf.c, src/qemu/qemu_conf.c, src/qemu/qemu_driver.c,
  src/xen/xend_internal.c, src/xen/xm_internal.c: Update for changed
  struct containing VNC password
2010-11-09 11:47:13 +00:00
Daniel P. Berrange
b5c9920955 Add SPICE support for QEMU driver configuration file
In common with VNC, the QEMU driver configuration file is used
specify the host level TLS certificate location and a default
password / listen address

* src/qemu/qemu.conf: Add spice_listen, spice_tls,
  spice_tls_x509_cert_dir & spice_password config params
* src/qemu/qemu_conf.c, src/qemu/qemu_conf.h: Parsing of
  spice config parameters and updating -spice arg generation
  to use them
* tests/qemuxml2argvdata/qemuxml2argv-graphics-spice-rhel6.args,
  tests/qemuxml2argvtest.c: Expand test case to cover driver
  level configuration
2010-11-09 11:47:05 +00:00
Daniel P. Berrange
ed0d9f6c0c Support automatic port number allocation for SPICE
* src/qemu/qemu_driver.c: Allocate the TCP ports for SPICE
  before starting guest
2010-11-09 11:46:56 +00:00
Daniel Veillard
1e4c45999e Read the host sysinfo for the QEmu driver
Read and store the data when initializing the driver.
2010-11-08 15:14:50 +01:00
Matthias Bolte
b5f8691ee2 qemu: Remove redundant slash in save directory path 2010-11-05 20:06:46 +01:00
Daniel P. Berrange
a51ccaf828 Revert commit 06f81c63eb
Commit 06f81c63eb attempted to make
QEMU driver ignore the failure to relabel 'stdin_path' if it was
on NFS. The actual result was that it ignores *all* failures to
label any aspect of the VM, unless stdin_path is non-NULL and
is not on NFS.

* src/qemu/qemu_driver.c: Treat all relabel failures as terminal
2010-11-02 14:37:26 +00:00
Diego Elio Pettenò
5919afe3c6 qemu: add the USB devices to the cgroup whitelist
Make sure that the QEmu process within the cgroup can access the device
file for the USB device that has to be connected to the virtual domain.
2010-11-01 10:19:51 -06:00
KAMEZAWA Hiroyuki
f69ce3feb0 qemu: check compression program availability of virsh save and dump 2010-10-29 10:22:08 -06:00
KAMEZAWA Hiroyuki
95a17abda7 add compression support for "virsh dump"
Add dump_image_format[] to qemu.conf and support compressed dump
at virsh dump. coredump compression is important for saving disk space
in an environment where multiple guests run.

In general, "disk space for dump" is specially allocated and will be
a dead space in the system. It's used only at emergency. So, it's better
to have both of save_image_format and dump_image_format. "save" is done
in scheduled manner with enough calculated disk space for it.

This code reuses some of save_image_format[] and supports the same format.

Changelog:
 - modified libvirtd_qemu.aug
 - modified test_libvirtd_qemu.aug
 - fixed error handling of qemudSaveCompressionTypeFromString()
2010-10-29 10:04:34 -06:00
Lai Jiangshan
41b2cee2a8 qemu_driver: add virCgroupMounted
When we mount any cgroup without "-o devices", we will fail to start vms:

error: Failed to start domain vm1
error: Unable to deny all devices for vm1: No such file or directory

When we mount any cgroup without "-o cpu", we will fail to get schedinfo:
Scheduler      : posix
error: unable to get cpu shares tunable: No such file or directory

We should only use the cgroup controllers which are mounted on host.
So I add virCgroupMounted() for qemuCgroupControllerActive()

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
2010-10-29 09:46:25 -06:00
Eric Blake
054d43f570 qemu: check for vm after starting a job
https://bugzilla.redhat.com/show_bug.cgi?id=638285 - when migrating
a guest, it was very easy to provoke a race where an application
could query block information on a VM that had just been migrated
away.  Any time qemu code obtains a job lock, it must also check
that the VM was not taken down in the time where it was waiting
for the lock.

* src/qemu/qemu_driver.c (qemudDomainSetMemory)
(qemudDomainGetInfo, qemuDomainGetBlockInfo): Check that vm still
exists after obtaining job lock, before starting monitor action.
2010-10-28 08:56:03 -06:00
Daniel P. Berrange
8dc136b5fc Add disk/net resource auditing to QEMU driver
Add auditing of all initial disk/net assignments to QEMU guests
at startup. Add auditing for all hotplug & unplug events and
disk media changes.

* src/qemu/qemu_driver.c: Add disk/net resource auditing
2010-10-27 17:03:22 +01:00
Daniel P. Berrange
160b5479f2 Add auditing of security label in QEMU driver
Add auditing of the allocated security label in the QEMU driver
VM startup code

* src/qemu/qemu_driver.c: Audit security label
2010-10-27 17:03:22 +01:00
Daniel P. Berrange
62622f841a Add auditing of start/stop events to the QEMU driver
Add audit hooks to report all start and stop events on QEMU
guest domains.

* src/qemu/qemu_driver.c: Audit start/stop events
2010-10-27 17:03:21 +01:00
Daniel P. Berrange
43e7e8f614 Remove all auditing hooks from libvirtd dispatch code
Revert most of commit a8b5f9bd27.
The audit hooks will be re-added directly in the QEMU driver code
in a future commit

* daemon/remote.c: Remove all audit logging hooks
* src/qemu/qemu_driver.c: Remove all audit logging hooks
2010-10-27 17:03:21 +01:00
Matthias Bolte
a1109a7c7c qemu: Exit on first error in qemuDomainGetMemoryParameters
There is no point in trying to fill params beyond the first error,
because when qemuDomainGetMemoryParameters returns -1 then the caller
cannot detect which values in params are valid.
2010-10-20 19:33:11 +02:00
Matthias Bolte
916f95b7aa Rename VIR_DOMAIN_SWAP_HARD_LIMIT to VIR_DOMAIN_MEMORY_SWAP_HARD_LIMIT
To get them under the common VIR_DOMAIN_MEMORY_* prefix.
2010-10-20 19:33:11 +02:00
Miloslav Trmač
a8b5f9bd27 Audit VM start/stop/suspend/resume
Most operations are audited at the libvirtd level; auditing in
src/libvirt.c would result in two audit entries per operation (one in
the client, one in libvirtd).

The only exception is a domain stopping of its own will (e.g. because
the user clicks on "shutdown" inside the interface).  There can often be
no client connected at the time the domain stops, so libvirtd does not
have any virConnectPtr object on which to attach an event watch.  This
patch therefore adds auditing directly inside the qemu driver (other
drivers are not supported).
2010-10-19 17:31:31 +01:00
Eric Blake
28a3605906 vcpu: complete vcpu support in qemu driver
* src/qemu/qemu_driver.c (qemudDomainSetVcpusFlags)
(qemudDomainGetVcpusFlags): Support all feasible flag
combinations.
2010-10-19 10:06:38 -06:00
Eric Blake
4617eedfae vcpu: support maxvcpu in domain_conf
Although this patch adds a distinction between maximum vcpus and
current vcpus in the XML, the values should be identical for all
drivers at this point.  Only in subsequent per-driver patches will
a distinction be made.

In general, virDomainGetInfo should prefer the current vcpus.

* src/conf/domain_conf.h (_virDomainDef): Adjust vcpus to unsigned
short, to match virDomainGetInfo limit.  Add maxvcpus member.
* src/conf/domain_conf.c (virDomainDefParseXML)
(virDomainDefFormat): parse and print out vcpu details.
* src/xen/xend_internal.c (xenDaemonParseSxpr)
(xenDaemonFormatSxpr): Manage both vcpu numbers, and require them
to be equal for now.
* src/xen/xm_internal.c (xenXMDomainConfigParse)
(xenXMDomainConfigFormat): Likewise.
* src/phyp/phyp_driver.c (phypDomainDumpXML): Likewise.
* src/openvz/openvz_conf.c (openvzLoadDomains): Likewise.
* src/openvz/openvz_driver.c (openvzDomainDefineXML)
(openvzDomainCreateXML, openvzDomainSetVcpusInternal): Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainDumpXML, vboxDomainDefineXML):
Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainDumpXML): Likewise.
* src/xenapi/xenapi_utils.c (createVMRecordFromXml): Likewise.
* src/esx/esx_vmx.c (esxVMX_ParseConfig, esxVMX_FormatConfig):
Likewise.
* src/qemu/qemu_conf.c (qemuBuildSmpArgStr)
(qemuParseCommandLineSmp, qemuParseCommandLine): Likewise.
* src/qemu/qemu_driver.c (qemudDomainHotplugVcpus): Likewise.
* src/opennebula/one_conf.c (xmlOneTemplate): Likewise.
2010-10-19 10:05:51 -06:00
Eric Blake
50c51f13e2 vcpu: make old API trivially wrap to new API
Note - this wrapping is completely mechanical; the old API will
function identically, since the new API validates that the exact
same flags are provided by the old API.  On a per-driver basis,
it may make sense to have the old API pass a different set of flags,
but that should be done in the per-driver patch that implements
the full range of flag support in the new API.

* src/esx/esx_driver.c (esxDomainSetVcpus, escDomainGetMaxVpcus):
Move guts...
(esxDomainSetVcpusFlags, esxDomainGetVcpusFlags): ...to new
functions.
(esxDriver): Trivially support the new API.
* src/openvz/openvz_driver.c (openvzDomainSetVcpus)
(openvzDomainSetVcpusFlags, openvzDomainGetMaxVcpus)
(openvzDomainGetVcpusFlags, openvzDriver): Likewise.
* src/phyp/phyp_driver.c (phypDomainSetCPU)
(phypDomainSetVcpusFlags, phypGetLparCPUMAX)
(phypDomainGetVcpusFlags, phypDriver): Likewise.
* src/qemu/qemu_driver.c (qemudDomainSetVcpus)
(qemudDomainSetVcpusFlags, qemudDomainGetMaxVcpus)
(qemudDomainGetVcpusFlags, qemuDriver): Likewise.
* src/test/test_driver.c (testSetVcpus, testDomainSetVcpusFlags)
(testDomainGetMaxVcpus, testDomainGetVcpusFlags, testDriver):
Likewise.
* src/vbox/vbox_tmpl.c (vboxDomainSetVcpus)
(vboxDomainSetVcpusFlags, virDomainGetMaxVcpus)
(virDomainGetVcpusFlags, virDriver): Likewise.
* src/xen/xen_driver.c (xenUnifiedDomainSetVcpus)
(xenUnifiedDomainSetVcpusFlags, xenUnifiedDomainGetMaxVcpus)
(xenUnifiedDomainGetVcpusFlags, xenUnifiedDriver): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDomainSetVcpus)
(xenapiDomainSetVcpusFlags, xenapiDomainGetMaxVcpus)
(xenapiDomainGetVcpusFlags, xenapiDriver): Likewise.
(xenapiError): New helper macro.
2010-10-19 10:03:33 -06:00
Eric Blake
dd255d6405 vcpu: define internal driver API
* src/driver.h (virDrvDomainSetVcpusFlags)
(virDrvDomainGetVcpusFlags): New typedefs.
(_virDriver): New callback members.
* src/esx/esx_driver.c (esxDriver): Add stub for driver.
* src/lxc/lxc_driver.c (lxcDriver): Likewise.
* src/opennebula/one_driver.c (oneDriver): Likewise.
* src/openvz/openvz_driver.c (openvzDriver): Likewise.
* src/phyp/phyp_driver.c (phypDriver): Likewise.
* src/qemu/qemu_driver.c (qemuDriver): Likewise.
* src/remote/remote_driver.c (remote_driver): Likewise.
* src/test/test_driver.c (testDriver): Likewise.
* src/uml/uml_driver.c (umlDriver): Likewise.
* src/vbox/vbox_tmpl.c (Driver): Likewise.
* src/xen/xen_driver.c (xenUnifiedDriver): Likewise.
* src/xenapi/xenapi_driver.c (xenapiDriver): Likewise.
2010-10-19 10:00:47 -06:00
Dan Kenigsberg
b2c9a87940 root_squash: virFileOperation may fail with EPERM too
Over root-squashing nfs, when virFileOperation() is called as uid==0,
it may fail with EACCES, but also with EPERM, due to
virFileOperationNoFork()'s failed attemp to chown a writable file.

qemudDomainSaveFlag() should expect this case, too.
2010-10-19 15:26:32 +02:00
Dan Kenigsberg
b7bd75c4c0 Run initgroups() in qemudOpenAsUID()
qemudOpenAsUID is intended to open a file with the credentials of a
specified uid. Current implementation fails if the file is accessible to
one of uid's groups but not owned by uid.

This patch replaces the supplementary group list that the child process
inherited from libvirtd with the default group list of uid.
2010-10-19 15:22:57 +02:00
Laine Stump
d3fec47f81 Fix warning about a non-literal format string in qemu_driver.c 2010-10-15 11:34:38 -04:00
Jiri Denemark
f93924f465 qemu: Prohibit migration of guests with host devices
Explicitly raising a nice error in the case user tries to migrate a
guest with assigned host devices is much better than waiting for a
mysterious error with no clue for the reason.
2010-10-14 09:36:54 +02:00
Stefan Berger
4435f3c477 nwfilter: resolve deadlock between VM ops and filter update
This is from a bug report and conversation on IRC where Soren reported that while a filter update is occurring on one or more VMs (due to a rule having been edited for example), a deadlock can occur when a VM referencing a filter is started.

The problem is caused by the two locking sequences of

qemu driver, qemu domain, filter             # for the VM start operation
filter, qemu_driver, qemu_domain            # for the filter update operation

that obviously don't lock in the same order. The problem is the 2nd lock sequence. Here the qemu_driver lock is being grabbed in qemu_driver:qemudVMFilterRebuild()

The following solution is based on the idea of trying to re-arrange the 2nd sequence of locks as follows:

qemu_driver, filter, qemu_driver, qemu_domain

and making the qemu driver recursively lockable so that a second lock can occur, this would then lead to the following net-locking sequence

qemu_driver, filter, qemu_domain

where the 2nd qemu_driver lock has been ( logically ) eliminated.

The 2nd part of the idea is that the sequence of locks (filter, qemu_domain) and (qemu_domain, filter) becomes interchangeable if all code paths where filter AND qemu_domain are locked have a preceding qemu_domain lock that basically blocks their concurrent execution

So, the following code paths exist towards qemu_driver:qemudVMFilterRebuild where we now want to put a qemu_driver lock in front of the filter lock.

-> nwfilterUndefine()   [ locks the filter ]
    -> virNWFilterTestUnassignDef()
        -> virNWFilterTriggerVMFilterRebuild()
            -> qemudVMFilterRebuild()

-> nwfilterDefine()
    -> virNWFilterPoolAssignDef() [ locks the filter ]
        -> virNWFilterTriggerVMFilterRebuild()
            -> qemudVMFilterRebuild()

-> nwfilterDriverReload()
    -> virNWFilterPoolLoadAllConfigs()
        ->virNWFilterPoolObjLoad()
            -> virNWFilterPoolAssignDef() [ locks the filter ]
                -> virNWFilterTriggerVMFilterRebuild()
                    -> qemudVMFilterRebuild()

-> nwfilterDriverStartup()
    -> virNWFilterPoolLoadAllConfigs()
        ->virNWFilterPoolObjLoad()
            -> virNWFilterPoolAssignDef() [ locks the filter ]
                -> virNWFilterTriggerVMFilterRebuild()
                    -> qemudVMFilterRebuild()

Qemu is not the only driver using the nwfilter driver, but also the UML driver calls into it. Therefore qemuVMFilterRebuild() can be exchanged with umlVMFilterRebuild() along with the driver lock of qemu_driver that can now be a uml_driver. Further, since UML and Qemu domains can be running on the same machine, the triggering of a rebuild of the filter can touch both types of drivers and their domains.

In the patch below I am now extending each nwfilter callback driver with functions for locking and unlocking the (VM) driver (UML, QEMU) and introduce new functions for locking all registered callback drivers and unlocking them. Then I am distributing the lock-all-cbdrivers/unlock-all-cbdrivers call into the above call paths. The last shown callpath starting with nwfilterDriverStart() is problematic since it is initialize before the Qemu and UML drives are and thus a lock in the path would result in a NULL pointer attempted to be locked -- the call to virNWFilterTriggerVMFilterRebuild() is never called, so we never lock either the qemu_driver or the uml_driver in that path. Therefore, only the first 3 paths now receive calls to lock and unlock all callback drivers. Now that the locks are distributed where it matters I can remove the qemu_driver and uml_driver lock from qemudVMFilterRebuild() and umlVMFilterRebuild() and not requiring the recursive locks.

For now I want to put this out as an RFC patch. I have tested it by 'stretching' the critical section after the define/undefine functions each lock the filter so I can (easily) concurrently execute another VM operation (suspend,start). That code is in this patch and if you want you can de-activate it. It seems to work ok and operations are being blocked while the update is being done.
I still also want to verify the other assumption above that locking filter and qemu_domain always has a preceding qemu_driver lock.
2010-10-13 10:33:26 -04:00
Nikunj A. Dadhania
261ad74e52 Adding memtunables to qemuSetupCgroup
QEmu startup will pick up the memory tunables specified in the domain
configuration file
2010-10-12 19:26:09 +02:00
Nikunj A. Dadhania
013fe4b848 Implement domainGetMemoryParamters for QEmu
Driver interface for getting memory parameters, eg. hard_limit,
soft_limit and swap_hard_limit based on cgroup support
2010-10-12 19:26:09 +02:00
Nikunj A. Dadhania
71d0b4275d Implement domainSetMemoryParamters for QEmu
Driver interface for setting memory hard_limit, soft_limit and swap
hard_limit based on cgroup support
2010-10-12 19:26:09 +02:00
Nikunj A. Dadhania
d390fce413 XML parsing for memory tunables
Adding parsing code for memory tunables in the domain xml file
also change the internal define structures used for domain memory
informations
Adds a new specific test
2010-10-12 19:26:09 +02:00
Nikunj A. Dadhania
0cd7823271 Adding virDomainSetMemoryParameters and virDomainGetMemoryParameters API
Public api to set/get memory tunables supported by the hypervisors.

dv:
* some cleanups in libvirt.c
* adding extra checks in libvirt.c new entry points

v4:
* Move exporting public API to this patch
* Add unsigned int flags to the public api for future extensions

v3:
* Add domainGetMemoryParamters and NULL in all the driver interface

v2:
* Initialize domainSetMemoryParameters to NULL in all the driver
  interface structure.
2010-10-12 19:26:09 +02:00
Soren Hansen
efe4e210b8 Rename qemudShrinkDisks to virDomainDiskRemove and move to domain_conf.c
Other drivers will need this same functionality, so move it to up to
conf/domain_conf.c and give it a more general name.

Signed-off-by: Soren Hansen <soren@linux2go.dk>
2010-08-24 20:17:48 +02:00
Eric Blake
4b93002358 build: delete dead comments
* src/qemu/qemu_driver.c (qemudGetProcessInfo): Clean up.
* src/uml/uml_driver.c (umlGetProcessInfo): Likewise.
* src/xen/sexpr.c (_string2sexpr): Likewise.
2010-08-19 16:09:46 -06:00