Enhance the QEMU migration monitoring loop, so that it can get
a signal to change migration speed on the fly

* src/qemu/qemu_domain.h: Add signal for changing speed on the fly
* src/qemu/qemu_driver.c: Wire up virDomainMigrateSetSpeed driver
* src/qemu/qemu_migration.c: Support signal for changing speed

* src/remote/remote_protocol.x: Define wire protocol
* daemon/remote.c, src/remote/remote_driver.c: Add new
  functions for virDomainMigrateSetSpeed API
* src/remote/remote_protocol.c, src/remote/remote_protocol.h,
  daemon/remote_dispatch_args.h, daemon/remote_dispatch_prototypes.h,
  daemon/remote_dispatch_table.h: Re-generate files

It is possible to set a migration speed limit when starting
migration. This new API allows the speed limit to be changed
on the fly to adjust to changing conditions

* src/driver.h, src/libvirt.c, src/libvirt_public.syms,
  include/libvirt/libvirt.h.in: Add virDomainMigrateSetMaxSpeed
* 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/vmware/vmware_driver.c, src/xen/xen_driver.c,
  src/libxl/libxl_driver.c: Stub new API

* AUTHORS: Update, to satisfy 'make syntax-check'.

The xen RPM in Fedora isn't new enough to support libxl builds
yet. Disable it until Fedora 16

* libvirt.spec.in: Disable libxl on Fedora < 16

fallback to HMP drive_add/drive_del commands if not found in QMP

Avoids calling text monitor methods when it is know they will not
succeed and also results in nicer error messages.

Fix for bug https://bugzilla.redhat.com/show_bug.cgi?id=618970

The "prepare" hook is called very early in the VM statup process
before device labeling, so that it can allocate ressources not
managed by libvirt, such as DRBD, or for instance create missing
bridges and vlan interfaces.
* src/util/hooks.c src/util/hooks.h: add definitions for new hooks
  VIR_HOOK_QEMU_OP_PREPARE and VIR_HOOK_QEMU_OP_RELEASE
* src/qemu/qemu_process.c: use them in qemuProcessStart and
  qemuProcessStop()

Wen Congyang gained commiter access

Created a new section of previous commiters to the project
but not involved much anymore: Karel Zak, Atsushi SAKAI,
Dave Leskovec and Dan Smith

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.

qemu_monitor was already returning -1 and setting errno to EINVAL
on any attempt to send an fd without a unix socket, but this was
a silent failure in the case of qemuDomainAttachHostPciDevice.
Meanwhile, qemuDomainAttachNetDevice was doing some sanity checking
for a better error message; it's better to consolidate that to a
central point in the API.

* src/qemu/qemu_hotplug.c (qemuDomainAttachNetDevice): Move sanity
checking...
* src/qemu/qemu_monitor.c (qemuMonitorSendFileHandle): ...into
central location.
Suggested by Chris Wright.

https://bugzilla.redhat.com/show_bug.cgi?id=684655 points out
a regression introduced in commit 2215050e - non-root users
can't connect to qemu:///session because libvirtd dies when
it can't use pciaccess initialization.

* src/node_device/node_device_udev.c (udevDeviceMonitorStartup):
Don't abort udev driver (and libvirtd overall) if non-root user
can't use pciaccess.

Valgrind caught that our log wrap-around was going 1 past the end.
Regression introduced in commit b16f47ab; previously the
buffer was static and size+1 bytes, but now it is dynamic and
exactly size bytes.

* src/util/logging.c (virLogStr): Don't write past end of log.

We have reported error in the function prepareCall(), and
the error is not only OOM error. So we should not report
OOM error in the function call() when prepareCall() failed.

If virFileIsExecutable is to replace access(file,X_OK), then
errno must be usable on failure.

* src/util/util.c (virFileIsExecutable): Set errno on failure.

<imagelable> is not generated by running domain, actually we parse
it in src/conf/domain_conf.c, this patch is to fix it, otherwise any
validation (virt-xml-validate) on the domain xml dumped from shutoff
domain containing <imagelable> will fail.

* docs/schemas/domain.rng

The current description suggests that you always have to provide
a valid typeVer pointer. But if you want only the libvirt version
it's also possible to set type and typeVer to NULL to skip the
hypervisor part.

This patch enables cgroup controllers as much as possible by skipping
the creation of blkio controller when running with old kernels that
doesn't support multi-level directory for blkio controller.
Signed-off-by: NHu Tao <hutao@cn.fujitsu.com>
Signed-off-by: NEric Blake <eblake@redhat.com>

The libxenlight driver does not build against the tech preview
version of libxenlight in Xen 4.0.  Only enable building the
driver against more complete libxenlight found in Xen 4.1.

THREADS.txt states that the contents of vm should not be read or
modified while the vm lock is not held, but that the lock must not
be held while performing a monitor command.  This fixes all the
offenders that I could find.

* src/qemu/qemu_process.c (qemuProcessStartCPUs)
(qemuProcessInitPasswords, qemuProcessStart): Don't modify or
refer to vm state outside lock.
* src/qemu/qemu_driver.c (qemudDomainHotplugVcpus): Likewise.
* src/qemu/qemu_hotplug.c (qemuDomainChangeGraphicsPasswords):
Likewise.

This is detailed in:

  https://bugzilla.redhat.com/show_bug.cgi?id=688957

Since radvd is executed by daemonizing it, the attempt to exec the
radvd binary doesn't happen until after libvirtd has already received
an exit code from the intermediate forked process, so no error is
detected or logged by __virExec().

We can't require radvd as a prerequisite for the libvirt package (many
installations don't use IPv6, so they don't need it), so instead we
add in a check to verify there is an executable radvd binary prior to
trying to exec it.

This patch adds missing curly brackets to an if
statement in openvzListDefinedDomains()

* po/POTFILES.in: Add src/util/hash.c for 'make syntax-check'.

When SASL is active, it was possible that we read and decoded
more data off the wire than we initially wanted. The loop
processing this data terminated after only one message to
avoid delaying the calling thread, but this could delay
event delivery. As long as there is decoded SASL data in
memory, we must process it, before returning to the poll()
event loop.

This is a counterpart to the same kind of issue solved in

  commit 68d2c348

in a different area of the code

* src/remote/remote_driver.c: Process all pending SASL data

virExec would only resolved the binary to $PATH if no env
variables were being set. Since there is no execvep() API
in POSIX, we use virFindFileInPath to manually resolve
the binary and then use execv() instead of execvp().

Add a new xen driver based on libxenlight [1], which is the primary
toolstack starting with Xen 4.1.0.  The driver is stateful and runs
privileged only.

Like the existing xen-unified driver, the libxenlight driver is
accessed with xen:// URI.  Driver selection is based on the status
of xend.  If xend is running, the libxenlight driver will not load
and xen:// connections are handled by xen-unified.  If xend is not
running *and* the libxenlight driver is available, xen://
connections are deferred to the libxenlight driver.

V6:
 - Address several code style issues noted by Daniel Veillard
 - Make drive work with xen:/// URI
 - Hold domain object reference while domain is injected in
   libvirt event loop.  Race found and fixed by Markus Groß.

V5:
 - Ensure events are unregistered when domain private data
   is destroyed.  Discovered and fixed by Markus Groß.

V4:
 - Handle restart of libvirtd, reconnecting to previously
   started domains
 - Rebased to current master
 - Tested against Xen 4.1 RC7-pre (c/s 22961:c5d121fd35c0)

V3:
  - Reserve vnc port within driver when autoport=yes

V2:
  - Update to Xen 4.1 RC6-pre (c/s 22940:5a4710640f81)
  - Rebased to current master
  - Plug memory leaks found by Stefano Stabellini and valgrind
  - Handle SHUTDOWN_crash domain death event

[1] http://lists.xensource.com/archives/html/xen-devel/2009-11/msg00436.html

Calling most hash APIs is not safe from inside of an iterator callback.
Exceptions are APIs that do not modify the hash table and removing
current hash entry from virHashFroEach callback.

This patch make all APIs which are not safe fail instead of just relying
on the callback being nice not calling any unsafe APIs.

Steps to reproduce this bug:
# cat test.sh
  #! /bin/bash -x
  virsh start domain
  sleep 5
  virsh qemu-monitor-command domain 'cpu_set 2 online' --hmp
# while true; do ./test.sh ; done

Then libvirtd will crash.

The reason is that:
we add a reference of obj when we open the monitor. We will reduce this
reference when we free the monitor.

If the reference of monitor is 0, we will free monitor automatically and
the reference of obj is reduced.

But in the function qemuDomainObjExitMonitorWithDriver(), we reduce this
reference again when the reference of monitor is 0.

It will cause the obj be freed in the function qemuDomainObjEndJob().

Then we start the domain again, and libvirtd will crash in the function
virDomainObjListSearchName(), because we pass a null pointer(obj->def->name)
to strcmp().
Signed-off-by: NWen Congyang <wency@cn.fujitsu.com>

This bug was reported by Shi Jin(jinzishuai@gmail.com):
=============
# virsh attach-disk RHEL6RC /var/lib/libvirt/images/test3.img vdb \
        --driver file --subdriver qcow2
Disk attached successfully

# virsh save RHEL6RC /var/lib/libvirt/images/memory.save
Domain RHEL6RC saved to /var/lib/libvirt/images/memory.save

# virsh restore /var/lib/libvirt/images/memory.save
error: Failed to restore domain from /var/lib/libvirt/images/memory.save
error: internal error unsupported driver name 'file'
       for disk '/var/lib/libvirt/images/test3.img'
=============

We check the driver name when we start or restore VM, but we do
not check it while attaching a disk. This adds the same check on disk
driverName used in qemuBuildCommandLine to qemudDomainAttachDevice.
Signed-off-by: NWen Congyang <wency@cn.fujitsu.com>

* docs/logging.html.in: document the fact that starting from
  0.9.0 the server logs goes to libvirtd.log instead of syslog
  by default, describe the debug buffer, restructure the page
  and add a couple more examples

As pointed out, locking the buffer from the signal handler
cannot been guaranteed to be safe, so to avoid any hazard
we prefer the trade off of dumping logs possibly messed up
by concurrent logging activity rather than risk a daemon
crash.

* src/util/logging.c: change virLogEmergencyDumpAll() to not
  take any lock on the log buffer but reset buffer content variables
  to an empty set before starting the actual dump.

Steps to reproduce this bug:
# virsh qemu-monitor-command domain 'cpu_set 2 online' --hmp
The domain has 2 cpus, and we try to set the third cpu online.
The qemu crashes, and this command will hang.

The reason is that the refs is not 1 when we unwatch the monitor.
We lock the monitor, but we do not unlock it. So virCondWait()
will be blocked.
Signed-off-by: NWen Congyang <wency@cn.fujitsu.com>

Make virDomainObjParseNode() static since it is called only
in one file.

* Correct the documentation for cgroup: the swap_hard_limit indicates
  mem+swap_hard_limit.
* Change cgroup private apis to: virCgroupGet/SetMemSwapHardLimit
Signed-off-by: NNikunj A. Dadhania <nikunj@linux.vnet.ibm.com>

I'm proposing we make use of $PCIDIR/reset in qemu-kvm to reset
devices on VM reset.  We need to add it to libvirt's list of
files that get ownership for device assignment.
Signed-off-by: NAlex Williamson <alex.williamson@redhat.com>