Commit id '0e2d7305' modified the code to allow a negative value to be
supplied for the bandwidth argument of the various block virsh commands
and the migrate-setspeed; however, it failed to update the man page to
describe the "feature" whereby a very large value could be interpreted
by the hypervisor to mean maximum value allowed. Although initially
designed to handle a -1 value, the reality is just about any negative
value could be provided and essentially perform the same feature.

https://bugzilla.redhat.com/show_bug.cgi?id=1087104

Commit id 'c6212539' explicitly allowed a negative value to be used for
offset and length as a shorthand for the largest value after commit id
'f18c02ec' modified virStrToLong_ui() to essentially disallow a negative
value.

However, allowing a negative value for offset ONLY worked if the negative
value was -1 since the eventual lseek() does allow a -1 to mean the end
of the file.  Providing other negative values resulted in errors such as:

$ virsh vol-download --pool default qcow3-vol2 /home/vm-images/raw \
  --offset -2 --length -1000
error: cannot download from volume qcow3-vol2
error: Unable to seek /home/vm-images/qcow3-vol2 to 18446744073709551614: Invalid argument

$

Thus, it seems unreasonable to expect or allow a negative value for offset
since the only benefit is to lseek() to the end of the file and then only
take advantage of how the OS would handle such a seek. For the purposes of
upload or download of volume data, that seems to be a no-op.  Therefore,
disallow a negative value for offset.

Additionally, modify the man page for vol-upload and vol-download to provide
more details regarding the valid values for both offset and length.

Test also the TITLE and DESCRIPTION metadata types.

Coverity complains about the return value of ioctl not being checked.

Even though we carry on when this fails (just like qemu-img does),
we can log an error.

For non-local storage drivers we can't expect to use the "scrub" tool to
wipe the volume. Split the code into a separate backend function so that
we can add protocol specific code later.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1118710

The next patch will move the storage volume wiping code into the
individual backends. This patch splits out the common code to wipe a
local volume into a separate backend helper so that the next patch is
simpler.

The previous commit 09d4d261 put the interleave at the wrong point;
it didn't allow interleaving with <memory>.

* docs/schema/domaincommon.rng (numatune): Fix interleave location.
* tests/qemuxml2argvdata/qemuxml2argv-numatune-memnode.xml: Adjust test.
Signed-off-by: NEric Blake <eblake@redhat.com>

For ESX, the code that builds XML descriptions for attached storage pools was
not setting the host count to anything when it returned a host name.

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

When domain is started with numatune memory mode strict and the
nodeset does not include host NUMA node with DMA and DMA32 zones, KVM
initialization fails.  This is because cgroup restrict even kernel
allocations.  We are already doing numa_set_membind() which does the
same thing, only it does not restrict kernel allocations.

This patch leaves the userspace numa_set_membind() in place and moves
the cpuset.mems setting after the point where monitor comes up, but
before vcpu and emulator sub-groups are created.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Currently, we only bind the whole QEMU domain to memory nodes
specified in nodemask altogether.  That, however, doesn't make much
sense when one wants to control from where the memory for particular
guest nodes should be allocated.  QEMU allows us to do that by
specifying 'host-nodes' parameter for the 'memory-backend-ram' object,
so let's use that.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

When qemu switched to using OptsVisitor for -numa parameter, it did
two things in the same patch.  One of them is that the numa parameter
is now visible in "query-command-line-options", the second one is that
it enabled using disjoint cpu ranges for -numa specification.  This
will be used in later patch.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

The numa patch series in qemu adds "memory-backend-ram" object type by
which we can tell whether we can use such objects.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

That can be lately achieved with by having .param == NULL in the
virQEMUCapsCommandLineProps struct.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

There were numerous places where numatune configuration (and thus
domain config as well) was changed in different ways.  On some
places this even resulted in persistent domain definition not to be
stable (it would change with daemon's restart).

In order to uniformly change how numatune config is dealt with, all
the internals are now accessible directly only in numatune_conf.c and
outside this file accessors must be used.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Since there was already public virDomainNumatune*, I changed the
private virNumaTune to match the same, so all the uses are unified and
public API is kept:

s/vir\(Domain\)\?Numa[tT]une/virDomainNumatune/g

then shrunk long lines, and mainly functions, that were created after
that:

sed -i 's/virDomainNumatuneMemPlacementMode/virDomainNumatunePlacement/g'

And to cope with the enum name, I haad to change the constants as
well:

s/VIR_NUMA_TUNE_MEM_PLACEMENT_MODE/VIR_DOMAIN_NUMATUNE_PLACEMENT/g

Last thing I did was at least a little shortening of already long
name:

s/virDomainNumatuneDef/virDomainNumatune/g
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

There are many places with numatune-related code that should be put
into special numatune_conf and this patch creates a basis for that.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

In XML format, by definition, order of fields should not matter, so
order of parsing the elements doesn't affect the end result.  When
specifying guest NUMA cells, we depend only on the order of the 'cell'
elements.  With this patch all older domain XMLs are parsed as before,
but with the 'id' attribute they are parsed and formatted according to
that field.  This will be useful when we have tuning settings for
particular guest NUMA node.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

to ease the review of commits to follow.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Excerpt from the virCommandAddArgBuffer() description: "Correctly
transfers memory errors or contents from buf to cmd."
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

to ease the review of commits to follow.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

This patch adds support for the QEMU vhost-user feature to libvirt.
vhost-user enables the communication between a QEMU virtual machine
and other userspace process using the Virtio transport protocol.
It uses a char dev (e.g. Unix socket) for the control plane,
while the data plane based on shared memory.

The XML looks like:

<interface type='vhostuser'>
    <mac address='52:54:00:3b:83:1a'/>
    <source type='unix' path='/tmp/vhost.sock' mode='server'/>
    <model type='virtio'/>
</interface>
Signed-off-by: NMichele Paolino <m.paolino@virtualopensystems.com>
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1119173 documents that
commit eaba79d2 was flawed in the implementation of the
VIR_DOMAIN_BLOCK_JOB_ABORT_ASYNC flag when it comes to completing
a blockcopy.  Basically, the qemu pivot action is async (the QMP
command returns immediately, but the user must wait for the
BLOCK_JOB_COMPLETE event to know that all I/O related to the job
has finally been flushed), but the libvirt command was documented
as synchronous by default.  As active block commit will also be
using this code, it is worth fixing now.

* src/qemu/qemu_driver.c (qemuDomainBlockJobImpl): Don't skip wait
loop after pivot.
Signed-off-by: NEric Blake <eblake@redhat.com>

Now that we've finally fixed all the violators, it's time to
enforce that any pointer to a const object is never freed (it
is aliasing some other memory, where the non-const original
should be freed instead).  Alas, the code still needs a normal
vs. Coverity version, but at least we are still guaranteeing
that the macro call evaluates its argument exactly once.

I verified that we still get the following compiler warnings,
which in turn halts the build thanks to -Werror on gcc (hmm,
gcc 4.8.3's placement of the ^ for ?: type mismatch is a bit
off, but that's not our problem):

    int oops1 = 0;
    VIR_FREE(oops1);
    const char *oops2 = NULL;
    VIR_FREE(oops2);
    struct blah { int dummy; } oops3;
    VIR_FREE(oops3);

util/virauthconfig.c:159:35: error: pointer/integer type mismatch in conditional expression [-Werror]
     VIR_FREE(oops1);
                                   ^
util/virauthconfig.c:161:5: error: passing argument 1 of 'virFree' discards 'const' qualifier from pointer target type [-Werror]
     VIR_FREE(oops2);
     ^
In file included from util/virauthconfig.c:28:0:
util/viralloc.h:79:6: note: expected 'void *' but argument is of type 'const void *'
 void virFree(void *ptrptr) ATTRIBUTE_NONNULL(1);
      ^
util/virauthconfig.c:163:35: error: type mismatch in conditional expression
     VIR_FREE(oops3);
                                   ^

* src/util/viralloc.h (VIR_FREE): No longer cast away const.
* src/xenapi/xenapi_utils.c (xenSessionFree): Work around bogus
header.
Signed-off-by: NEric Blake <eblake@redhat.com>

Add file in storagevolxml2xmlin and storagevolxml2xmlout, let
storagevolxml2xmltest and storagevolschematest cover 'nocow'.
Add test case to storagevolxml2argvtest to cover 'nocow'.
Signed-off-by: NChunyan Liu <cyliu@suse.com>

Add 'nocow' to storage volume xml so that user can have an option
to set NOCOW flag to the newly created volume. It's useful on btrfs
file system to enhance performance.

Btrfs has low performance when hosting VM images, even more when the guest
in those VM are also using btrfs as file system. One way to mitigate this
bad performance is to turn off COW attributes on VM files. Generally, there
are two ways to turn off COW on btrfs: a) by mounting fs with nodatacow,
then all newly created files will be NOCOW. b) per file. Add the NOCOW file
attribute. It could only be done to empty or new files.

This patch tries the second way, according to 'nocow' option, it could set
NOCOW flag per file:
for raw file images, handle 'nocow' in libvirt code; for non-raw file images,
pass 'nocow=on' option to qemu-img, and let qemu-img to handle that (requires
qemu-img version >= 2.1).
Signed-off-by: NChunyan Liu <cyliu@suse.com>

In many places we define a variable as a 'const char *' when in fact
we modify it just a few lines below. Or even free it. We should not do
that.

There's one exception though, in xenSessionFree() xenapi_utils.c. We
are freeing the xen_session structure which is defined in
xen/api/xen_common.h public header. The structure contains session_id
which is type of 'const char *' when in fact it should have been just
'char *'. So I'm leaving this unmodified, just noticing the fact in
comment.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

When the backing store of a volume wasn't accessible while updating the
volume definition the call would fail altogether. In cases where we
currently (incorrectly) treat remote backing stores as local one this
might lead to strange errors.

Ignore the opening errors until we figure out how to track proper volume
metadata.

Use the backing store parser to properly create the information about a
volume's backing store. Unfortunately as the storage driver isn't
prepared to allow volumes backed by networked filesystems add a
workaround that will avoid changing the XML output.

Move the processing of the backend metadata directly to the helper
instead of passing it through arguments to the function.

virStorageBackendFileSystemRefresh() used "cleanup" label just for error
exits and didn't meet libvirt's standard for braces in one case.

As we have a nested pointer for storing the backing store of a volume
there's no need to store it in a separate struct.

Assign the value we're comparing:
(val = func()) < 0
instead of assigning the comparison value:
(val = func() < 0)

Both were introduced along with the code,
the TLS tests by commit bd789dff in 0.9.4
net events by commit de87691f in 1.2.2.

Note that the event id type fix is a no-op:
vshNetworkEventIdTypeFromString can only return
-1 (failure) and the event is never used or
0 (the only possible event) and the value of 0 < 0 is still 0.

https://bugzilla.redhat.com/show_bug.cgi?id=1119592

Introduced by commit 62927dd8 v0.7.6.

Commit 20e01504 broke 'make rpm':

error: line 540: Unknown tag:     %elif 020 >= 12 || 0 >= 6

Apparently, even though shell has elif so that you can do a chain
of conditionals, the rpm spec file does not, and you have to nest
things instead.

* libvirt.spec.in: Convert %elif to proper nested %if.
Signed-off-by: NEric Blake <eblake@redhat.com>