storage: return -1 when fs pool can't be mounted

Don't reuse the return value of virStorageBackendFileSystemIsMounted.
If it's 0, we'd return it even if the mount command failed.

Also, don't report another error if it's -1, since one has already
been reported.

Introduced by 258e06c.

https://bugzilla.redhat.com/show_bug.cgi?id=981251
(cherry picked from commit 13fde7ceab556804dc6cfb3e56938fb948ffe83d)
qemu: fix return value of qemuDomainBlockPivot on errors

If qemuMonitorBlockJob returned 0, qemuDomainBlockPivot
might return 0 even if an error occured.

https://bugzilla.redhat.com/show_bug.cgi?id=977678
(cherry picked from commit c34107dfd3a25232255e6d6f559b1306ef99bb3b)
libxl: fix build with Xen4.3

Xen 4.3 fixes a mistake in the libxl event handler signature where the
event owned by the application was defined as const.  Detect this and
define the libvirt libxl event handler signature appropriately.
(cherry picked from commit 43b0ff5b1eb7fbcdc348b2a53088a7db939d5e48)
Cope with missing swap cgroup controls

It is possible to build a kernel without swap cgroup controls
present. This causes a fatal error when querying memory
parameters. Treat missing swap controls as meaning "unlimited".
The fatal error remains if the user tries to actually change
the limit.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit f493d83fbd3257453e63f2f32ee90a216fd531c1)
Add docs about cgroups layout and usage

Describe the new cgroups layout, how to customize placement
of guests and what virsh commands are used to access the
parameters.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 486a86eb184c008c5957fb68c63f163289f3344b)
Escaping leading '.' in cgroup names

Escaping a leading '.' with '_' in the cgroup names

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 0ced83dcfbb19af1201202e1af0a7073c338aabd)
Fix starting domains when kernel has no cgroups support

Found that I was unable to start existing domains after updating
to a kernel with no cgroups support

  # zgrep CGROUP /proc/config.gz
  # CONFIG_CGROUPS is not set
  # virsh start test
  error: Failed to start domain test
  error: Unable to initialize /machine cgroup: Cannot allocate memory

virCgroupPartitionNeedsEscaping() correctly returns errno (ENOENT) when
attempting to open /proc/cgroups on such a system, but it was being
dropped in virCgroupSetPartitionSuffix().

Change virCgroupSetPartitionSuffix() to propagate errors returned by
its callees.  Also check for ENOENT in qemuInitCgroup() when determining
if cgroups support is available.
(cherry picked from commit bbe97ae968eba60b71e0066d49f9fc909966d9d6)
Fix failure to detect missing cgroup partitions

Change bbe97ae968eba60b71e0066d49f9fc909966d9d6 caused the
QEMU driver to ignore ENOENT errors from cgroups, in order
to cope with missing /proc/cgroups. This is not good though
because many other things can cause ENOENT and should not
be ignored. The callers expect to see ENXIO when cgroups
are not present, so adjust the code to report that errno
when /proc/cgroups is missing

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit c2cf5f1c2abc81d607abe34bf5dc4c615a9b8b4d)
Re-add selinux/selinux.h to lxc_container.c

Re-add the selinux header to lxc_container.c since other
functions now use it, beyond the patch that was just
reverted.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 63ea1e5432b27861c116988336b688bbfae03048)
Don't mount selinux fs in LXC if selinux is disabled

Before trying to mount the selinux filesystem in a container
use is_selinux_enabled() to check if the machine actually
has selinux support (eg not booted with selinux=0)

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 95c6cc344bec8405636d2a59fc0c34e0581001ab)
udev: fix crash in libudev logging

Call virLogVMessage instead of virLogMessage, since libudev
called us with a va_list object, not a list of arguments.

Honor message priority and strip the trailing newline.

https://bugzilla.redhat.com/show_bug.cgi?id=969152
(cherry picked from commit f753dd62f951cc62e164421d0c6491f39e4c68ad)
qemu: Implement new QMP command for cpu hotplug

This patch implements support for the "cpu-add" QMP command that plugs
CPUs into a live guest. The "cpu-add" command was introduced in QEMU
1.5. For the hotplug to work machine type "pc-i440fx-1.5" is required.

(cherry picked from commit c12b2be5169298708cf727ed9ccd42e9d89a9737)
LXC: Create /dev/tty within a container

Many applications use /dev/tty to read from stdin.
e.g. zypper on openSUSE.

Let's create this device node to unbreak those applications.
As /dev/tty is a synonym for the current controlling terminal
it cannot harm the host or any other containers.

Signed-off-by: Richard Weinberger <richard@nod.at>
(cherry picked from commit 9a0ac6d9c21b914f887d2a1e0051b5beffa81bd7)

Conflicts:
	src/lxc/lxc_controller.c
Ensure non-root can read /proc/meminfo file in LXC containers

By default files in a FUSE mount can only be accessed by the
user which created them, even if the file permissions would
otherwise allow it. To allow other users to access the FUSE
mount the 'allow_other' mount option must be used. This bug
prevented non-root users in an LXC container from reading
the /proc/meminfo file.

https://bugzilla.redhat.com/show_bug.cgi?id=967977

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
(cherry picked from commit 922ebe4ead4a30a6a94731d31b980d0eae113894)
Fix blkdeviotune for shutoff domain

Function qemuDomainSetBlockIoTune() was checking QEMU capabilities
even when !(flags & VIR_DOMAIN_AFFECT_LIVE) and the domain was
shutoff, resulting in the following problem:

 virsh # domstate asdf; blkdeviotune asdf vda --write-bytes-sec 100
 shut off

 error: Unable to change block I/O throttle
 error: unsupported configuration: block I/O throttling not supported with this QEMU binary

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=965016
(cherry picked from commit 5af3ce827767707097affc5e001eab8cbabc28a7)
qemu: snapshot: Don't kill access to disk if snapshot creation fails

If snapshot creation failed for example due to invalid use of the
"REUSE_EXTERNAL" flag, libvirt killed access to the original image file
instead of the new image file. On machines with selinux this kills the
whole VM as the selinux context is enforced immediately.

* qemu_driver.c:qemuDomainSnapshotUndoSingleDiskActive():
    - Kill access to the new image file instead of the old one.

Partially resolves: https://bugzilla.redhat.com/show_bug.cgi?id=906639

(cherry picked from commit 177046753fa427609f217c319dba6fa465a4add4)
Check for existence of interface prior to setting terminate flag

https://bugzilla.redhat.com/show_bug.cgi?id=903480

During domain destruction it's possible that the learnIPAddressThread has
already removed the interface prior to the teardown filter path being run.
The teardown code would only be telling the thread to terminate.

(cherry picked from commit 64919d978e4cc910a4475f77c0f04b866051935d)
usb: don't spoil decimal addresses

For USB devices, dev->name gets formated as %.3o:%.3o even though the
numbers are decimal.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=967712
(cherry picked from commit dc0c7915697a902d6edc5820f5930653b7684c3c)
storage: Provide better error message if metadata pre-alloc is unsupported

Instead of a unknown flag error report that metadata pre-allocation is
not supported with the requested volume creation method.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=969982
(cherry picked from commit 77e7f69c3b88ae0a7364fa88334a483a247d7200)
qemu: Report the offset from host UTC for RTC_CHANGE event

https://bugzilla.redhat.com/show_bug.cgi?id=964177

Though both libvirt and QEMU's document say RTC_CHANGE returns
the offset from the host UTC, qemu actually returns the offset
from the specified date instead when specific date is provided
(-rtc base=$date).

It's not safe for qemu to fix it in code, it worked like that
for 3 years, changing it now may break other QEMU use cases.
What qemu tries to do is to fix the document:

http://lists.gnu.org/archive/html/qemu-devel/2013-05/msg04782.html

And in libvirt side, instead of replying on the value from qemu,
this converts the offset returned from qemu to the offset from
host UTC, by:

  /*
   * a: the offset from qemu RTC_CHANGE event
   * b: The specified date (-rtc base=$date)
   * c: the host date when libvirt gets the RTC_CHANGE event
   * offset: What libvirt will report
   */

  offset = a + (b - c);

The specified date (-rtc base=$date) is recorded in clock's def as
an internal only member (may be useful to exposed outside?).

Internal only XML tag "basetime" is introduced to not lose the
guest's basetime after libvirt restarting/reloading:

<clock offset='variable' adjustment='304' basis='utc' basetime='1370423588'/>

(cherry picked from commit e31b5cf393857a6ca78d148c19393e28dfb39de1)