3690 Commits

Author SHA1 Message Date
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
b0ef5c5367 Support SPICE channel security options
This extends the SPICE XML to allow channel security options

    <graphics type='spice' port='-1' tlsPort='-1' autoport='yes'>
      <channel name='main' mode='secure'/>
      <channel name='record' mode='insecure'/>
    </graphics>

Any non-specified channel uses the default, which allows both
secure & insecure usage

* src/conf/domain_conf.c, src/conf/domain_conf.h,
  src/libvirt_private.syms: Add XML syntax for specifying per
  channel security options for spice.
* src/qemu/qemu_conf.c: Configure channel security with spice
2010-11-09 11:47:26 +00:00
Daniel P. Berrange
6794a44b85 Support multiple QXL video cards
QEMU crashes & burns if you try multiple Cirrus video cards, but
QXL copes fine. Adapt QEMU config code to allow multiple QXL
video cards

* src/qemu/qemu_conf.c: Support multiple QXL video cards
2010-11-09 11:47:21 +00:00
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 P. Berrange
9b57fa65bd Implement QEMU/KVM support for SPICE graphics
This supports the -spice argument posted for review against
the latest upstream QEMU/KVM. This supports the bare minimum
config with port, TLS port & listen address. The x509 bits are
added in a later patch.

* src/qemu_conf.c, src/qemu_conf.h: Add SPICE flag. Check for
  -spice availability. Format -spice arg for command line
* qemuhelptest.c: Add SPICE flag
* qemuxml2argvdata/qemuxml2argv-graphics-spice.args: Add <graphics>
  for spice
* qemuxml2argvdata/qemuxml2argv-graphics-spice.xml: Add -spice arg
* qemuxml2argvtest.c: Add SPICE flag
2010-11-09 11:46:50 +00:00
Daniel P. Berrange
635f9ca1f3 Implement QEMU/KVM QXL video card support in QEMU driver
This supports the '-vga qxl' parameter in upstream QEMU/KVM
which has SPICE support added. This isn't particularly useful
until you get the next patch for -spice support. Also note that
while the libvirt XML supports multiple video devices, this
patch only supports a single one. A later patch can add support
for 2nd, 3rd, etc PCI devices for QXL

* src/qemu/qemu_conf.h: Flag for QXL support
* src/qemu/qemu_conf.c: Probe for '-vga qxl' support and implement it
* tests/qemuxml2argvtest.c, tests/qemuxml2xmltest.c,
  tests/qemuxml2argvdata/qemuxml2argv-graphics-spice.args,
  tests/qemuxml2argvdata/qemuxml2argv-graphics-spice.xml: Test
  case for generating spice args with RHEL6 kvm
2010-11-09 11:46:45 +00:00
Daniel P. Berrange
c909091b74 Add a <graphics> type for SPICE protocol
This adds an element

 <graphics type='spice' port='5903' tlsPort='5904' autoport='yes' listen='127.0.0.1'/>

This is the bare minimum that should be exposed in the guest
config for SPICE. Other parameters are better handled as per
host level configuration tunables

* docs/schemas/domain.rng: Define the SPICE <graphics> schema
* src/domain_conf.h, src/domain_conf.c: Add parsing and formatting
  for SPICE graphics config
* src/qemu_conf.c: Complain about unsupported graphics types
2010-11-09 11:46:27 +00:00
Daniel P. Berrange
3cf5b6f720 Add a QXL graphics card type to domain XML schema
* src/qemu_conf.c: Add dummy entry in enumeration
* docs/schemas/domain.rng: Add 'qxl' as a type for the <video> tag
* src/domain_conf.c, src/domain_conf.h: Add QXL to video type
  enumerations
2010-11-09 11:46:19 +00:00
Jiri Denemark
0011e91770 qemu: Fix non-literal format string 2010-11-09 11:08:45 +01:00
Daniel Veillard
54c0237ccb Add sysinfo/smbios support to the QEmu driver
The patch is based on the possiblity in the QEmu command line to
add -smbios options allowing to override the default values picked
by QEmu. We need to detect this first from QEmu help output.
If the domain is defined with smbios to be inherited from host
then we pass the values coming from the Host own SMBIOS, but
if the domain is defined with smbios to come from sysinfo, we
use the ones coming from the domain definition.

* src/qemu/qemu_conf.h: add the QEMUD_CMD_FLAG_SMBIOS_TYPE enum
  value
* src/qemu/qemu_conf.c: scan the help output for the smbios support,
  and if available add support based on the domain definitions,
  and host data
* tests/qemuhelptest.c: add the new enum in the outputs
2010-11-08 15:14:50 +01:00
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
a1de6ba0f1 Misc error handling fixes in text mode monitor commands
A couple of places in the text monitor were overwriting the
'ret' variable with a >= 0 value before success was actually
determined. So later error paths would not correctly return
the -1 value. The drive_add code was not checking for errors
like missing command

* src/qemu/qemu_monitor_text.c: Misc error handling fixes
2010-11-02 14:38:23 +00:00
Daniel P. Berrange
a51ccaf828 Revert commit 06f81c63ebc19cb0e51f9b397991f6d6ae56d090
Commit 06f81c63ebc19cb0e51f9b397991f6d6ae56d090 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 a8b5f9bd27d65c2ced064b9267ca31dee7ad9c86.
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
Diego Elio Pettenò
8efebd1761 qemu: don't use %.3d format for bus/addr of USB devices
When using 0-prefixed numbers, QEmu will interpret them as octal numbers
(as C convention says); this means that if you attach a device that has
addr > 10 (decimal) you're going to attach a different device.
2010-10-26 10:19:07 -06:00
Eric Blake
f22e670b4a qemu: work around dash 0.5.5 bug in managed save
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.
2010-10-26 09:31:42 -06:00
Jiri Denemark
69b7552154 qemu: Fix detection of drive readonly option
So far, readonly=on option is used when qemu supports -device. However,
there are qemu versions which support readonly option with -drive
although they don't have support for -device.
2010-10-26 10:31:50 +02:00
Daniel P. Berrange
497adba2d4 Expand virSocketFormat to be more flexible
The getnameinfo() function is more flexible than inet_ntop()
avoiding the need to if/else the code based on socket family.
Also make it support UNIX socket addrs and allow inclusion
of a port (service) address. Finally do proper error reporting
via normal APIs.

* src/conf/domain_conf.c, src/nwfilter/nwfilter_ebiptables_driver.c,
  src/qemu/qemu_conf.c: Fix error handling with virSocketFormat
* src/util/network.c: Rewrite virSocketFormat to use getnameinfo
  and cope with UNIX socket addrs.
2010-10-22 11:24:12 +01:00
Daniel P. Berrange
aa1e3f6706 Enable JSON and netdev features in QEMU >= 0.13
The QEMU 0.13 release is finally out and from testing in RHEL-6
we know that its JSON and netdev features are now good enough
for us to use by default.

* src/qemu/qemu_conf.c: Enable JSON + netdev for QEMU >= 0.13
2010-10-21 11:16:22 +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
John Morrissey
c08c7b0143 Add process= support for 'qemu-kvm -name'
This sets the process name to the same value as the Windows title,
but since the name is limited to 16 chars only this is kept as a
configuration option and turned off by default
* src/qemu/qemu.conf src/qemu/qemu_conf.[ch]: hceck for support in the
  QEmu help output, add the option in qemu conf file and augment
  qemudBuildCommandLine to add it if switched on
* src/qemu/libvirtd_qemu.aug src/qemu/test_libvirtd_qemu.aug: augment
  the augeas lenses accordingly
* tests/qemuhelptest.c: cope with the extra flag being detected now
2010-10-20 10:30:30 +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
d67c189e80 vcpu: improve vcpu support in qemu command line
* src/qemu/qemu_conf.c (qemuParseCommandLineSmp): Distinguish
between vcpus and maxvcpus, for new enough qemu.
* tests/qemuargv2xmltest.c (mymain): Add new test.
* tests/qemuxml2argvtest.c (mymain): Likewise.
* tests/qemuxml2xmltest.c (mymain): Likewise.
* tests/qemuxml2argvdata/qemuxml2argv-smp.args: New file.
2010-10-19 10:06:33 -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
Harsh Prateek Bora
75a6a9a8e0 new attribute accessmode to filesystem element
This introduces new attribute to filesystem element
to support customizable access mode for mount type.
Valid accessmode are: passthrough, mapped and squash.

Usage:
        <filesystem type='mount' accessmode='passthrough'>
          <source dir='/export/to/guest'/>
          <target dir='mount_tag'/>
        </filesystem>

passthrough is the default model if not specified, that's
also the current behaviour.
2010-10-14 15:08:24 +02:00
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
Daniel P. Berrange
f98a6cd6ae Enable support for nested SVM
This enables support for nested SVM using the regular CPU
model/features block. If the CPU model or features include
'svm', then the '-enable-nesting' flag will be added to the
QEMU command line. Latest out of tree patches for nested
'vmx', no longer require the '-enable-nesting' flag. They
instead just look at the cpu features. Several of the models
already include svm support, but QEMU was just masking out
the svm bit silently. So this will enable SVM on such
models

* src/qemu/qemu_conf.h: flag for -enable-nesting
* src/qemu/qemu_conf.c: Use -enable-nesting if VMX or SVM are in
  the CPUID
* src/cpu/cpu.h, src/cpu/cpu.c: API to check for a named feature
* src/cpu/cpu_x86.c: x86 impl of feature check
* src/libvirt_private.syms: Add cpuHasFeature
* src/qemuhelptest.c: Add nesting flag where required
2010-10-13 16:45:31 +01:00
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
Daniel P. Berrange
a5c646a770 Implement support for virtio plan9fs filesystem passthrough in QEMU
Make use of the existing <filesystem> element to support plan9fs
filesystem passthrough in the QEMU driver

    <filesystem type='mount'>
      <source dir='/export/to/guest'/>
      <target dir='/import/from/host'/>
    </filesystem>

NB, the target is not actually a directory, it is merely a arbitrary
string tag that is exported to the guest as a hint for where to mount
it.
2010-10-13 12:04:50 +01:00
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