The libxl driver was setting the backend field of libxl_device_disk
structure to LIBXL_DISK_BACKEND_TAP when the driver element of disk
configuration was not specified.  This needlessly forces the use of
blktap driver, which may not be loaded in dom0

https://bugzilla.redhat.com/show_bug.cgi?id=912488

Ian Campbell suggested that LIBXL_DISK_BACKEND_UNKNOWN is a better
default in this case

https://www.redhat.com/archives/libvir-list/2013-February/msg01126.html

Currently, if lzop decompression binary produces a warning, it
doesn't exit with zero status but 2 instead. Terrifying, but
true. However, warnings may be ignored using '--ignore-warn'
command line argument.  Moreover, in which case, the exit status
will be zero.

Commit 18937c3a introduced the
memory leak when client->msg.fds is copied to thecall->msg
and then never freed.

For both AttachDevice and UpdateDevice APIs, if the disk device
is 'cdrom' or 'floppy', the operations could be ejecting, updating,
and inserting. For either ejecting or updating, the shared disk
entry of the original disk src has to be removed, because it's
not useful anymore.

And since the original disk def will be changed, new disk def passed
as argument will be free'ed in qemuDomainChangeEjectableMedia, so
we need to copy the orignal disk def before
qemuDomainChangeEjectableMedia, to use it for qemuRemoveSharedDisk.

The disk def could be free'ed by qemuDomainChangeEjectableMedia,
which can thus cause crash if we reference the disk pointer. On
the other hand, we have to remove the added shared disk entry from
the table on error codepath.

The hash entry is changed from "ref" to {ref, @domains}. With this, the
caller can simply call qemuRemoveSharedDisk, without afraid of removing
the entry belongs to other domains. qemuProcessStart will obviously
benifit from it on error codepath (which calls qemuProcessStop to do
the cleanup).

Based on moving various checking into qemuAddSharedDisk, this
avoids the caller using it in wrong ways. Also this adds two
new checking for qemuCheckSharedDisk (disk device not 'lun'
and kernel doesn't support unpriv_sgio simply returns 0).

This moves the various checking into the helpers, to avoid the
callers missing the checking.

Automating a sorting check is the only way to ensure we don't
regress.  Suggested by Dan Berrange.

* src/check-symsorting.pl (check_sorting): Add a parameter,
validate that groups are in order, and that files exist.
* src/Makefile.am (check-symsorting): Adjust caller.
* src/libvirt_private.syms: Fix typo.
* src/libvirt_linux.syms: Fix file name.
* src/libvirt_vmx.syms: Likewise.
* src/libvirt_xenxs.syms: Likewise.
* src/libvirt_sasl.syms: Likewise.
* src/libvirt_libssh2.syms: Likewise.
* src/libvirt_esx.syms: Mention file name.
* src/libvirt_openvz.syms: Likewise.

Due to "feature"/"features" nasty typo, any features marked as mandatory
by one side of a migration are silently considered optional by the other
side. The following is the code that formats mandatory features in
migration cookie:

    for (i = 0 ; i < QEMU_MIGRATION_COOKIE_FLAG_LAST ; i++) {
        if (mig->flagsMandatory & (1 << i))
            virBufferAsprintf(buf, "  <feature name='%s'/>\n",
                              qemuMigrationCookieFlagTypeToString(i));
    }

Some functions were using virDomainDeviceInfo where virDevicePCIAddress
would suffice. Some were only using integers for slots and functions,
assuming the bus numbers are always 0.

Switch from virDomainDeviceInfoPtr to virDevicePCIAddressPtr:
qemuPCIAddressAsString
qemuDomainPCIAddressCheckSlot
qemuDomainPCIAddressReserveAddr
qemuDomainPCIAddressReleaseAddr

Switch from int slot to virDevicePCIAddressPtr:
qemuDomainPCIAddressReserveSlot
qemuDomainPCIAddressReleaseSlot
qemuDomainPCIAddressGetNextSlot

Deleted functions (they would take the same parameters
as ReserveAddr/ReleaseAddr do now.)
qemuDomainPCIAddressReserveFunction
qemuDomainPCIAddressReleaseFunction

Specifying ':' to suppress the error messages printed by getopt().
Then, distinguish the two types of errors.

Before:
 # virsh -c
   virsh: option requires an argument -- 'c'
   error: unsupported option '-?'. See --help.

After:
 # virsh -c
   error: option '-c' requires an argument

 # virsh -x
   error: unsupported option '-x'. See --help.

Purely mechanical (roughly, s/\n/~/; s/~~/\n/; sort by line;
s/~/\n/)

* src/libvirt_private.syms: Sort sections by header file name.

Recent renames were not reflected into the comments of
libvirt_private.syms; furthermore, since we mix private headers from
several directories into this file, knowing where the file lives
can be helpful.

* src/libvirt_private.sym: Reflect recent names.

We pass over the address/port start/end values many times so we put
them in structs.
Signed-off-by: NNatanael Copa <ncopa@alpinelinux.org>
Signed-off-by: NLaine Stump <laine@laine.org>

Let users set the port range to be used for forward mode NAT:

...
  <forward mode='nat'>
    <nat>
      <port start='1024' end='65535'/>
    </nat>
  </forward>
...
Signed-off-by: NNatanael Copa <ncopa@alpinelinux.org>
Signed-off-by: NLaine Stump <laine@laine.org>

Support setting which public ip to use for NAT via attribute
address in subelement <nat> in <forward>:

...
  <forward mode='nat'>
      <address start='1.2.3.4' end='1.2.3.10'/>
  </forward>
...

This will construct an iptables line using:

  '-j SNAT --to-source <start>-<end>'

instead of:

  '-j MASQUERADE'
Signed-off-by: NNatanael Copa <ncopa@alpinelinux.org>
Signed-off-by: NLaine Stump <laine@laine.org>

We need to drop the server lock before calling virObjectUnlock(client)
since in case we had the last reference to the client, its dispose
callback would be called and that could possibly try to lock the server
and cause a deadlock. This is exactly what happens when there is only
one QEMU domain running and it is marked to be autodestroyed when the
connection dies. This results in qemuProcessAutoDestroy ->
qemuProcessStop -> virNetServerRemoveShutdownInhibition call sequence,
where the last function locks the server.

The function does not report any errors so there should be no need too
reset an existing error first. Moreover, virTypedParamsFree is mostly
called in cleanup phase where it has the potential to reset any useful
reported earlier.

It doesn't make sense to print the unit (B) only with Ki, Mi, ...
prefixes. Even those poor bytes under 1 KiB are still bytes :-)

Gcc lets you do:

int ATTRIBUTE_NONNULL(1) foo(void *param);
int foo(void *param) ATTRIBUTE_NONNULL(1);
int ATTRIBUTE_NONNULL(1) foo(void *param) { ... }

but chokes on:

int foo(void *param) ATTRIBUTE_NONNULL(1) { ... }

However, since commit eefb881d, we have intentionally been disabling
ATTRIBUTE_NONNULL because of lame gcc handling of the attribute (that
is, gcc doesn't do decent warning reporting, then compiles code that
mysteriously fails if you break the contract of the attribute, which
is surprisingly easy to do), leaving it on only for Coverity (which
does a much better job of improved static analysis when the attribute
is present).

But completely eliding the macro makes it too easy to write code that
uses the fourth syntax option, if you aren't using Coverity.  So this
patch forces us to avoid syntax errors, even when not using the
attribute under gcc.  It also documents WHY we disable the warning
under gcc, rather than forcing you to find the commit log.

* src/internal.h (ATTRIBUTE_NONNULL): Expand to empty attribute,
rather than nothing, when on gcc.

so we don't try to change uid/git to 0 when probing capabilities.

The conversion to qemuCaps dropped the ability with qemu{,-kvm} 1.2 and
newer to set the lost tick policy for the PIT. While the
-no-kvm-pit-reinjection option is depreacated, it is still supported at
least through 1.4, it is better to not lose the functionality.

udevIfaceListAllInterface() used the udev_device after it had its ref
count decremented which results in a use after free issue.

/src/lxc/lxc_protocol.[ch] is autogenerated so add it to .gitignore

Coverity found the DACGenLabel was checking for mgr == NULL after a
possible dereference; however, in order to get into the function the
virSecurityManagerGenLabel would have already dereferenced sec_managers[i]
so the check was unnecessary. Same check is made in SELinuxGenSecurityLabel.

Coverity found that commit '41b5e845' had a possible NULL dereference on
arg->data processing

Changes from commit '3178df9a' removed the need for the sa_assert(infd).

Between revision 65fb9d49 and before this patch, an upgrade of libvirt while
VMs are running and instantiating iptables filtering rules due to nwfilter
rules, may leave stray iptables rules behind when shutting VMs down.
Left-over iptables rules may look like this:

Chain FP-vnet0 (1 references)
target     prot opt source               destination         
DROP       tcp  --  0.0.0.0/0            0.0.0.0/0            tcp spt:122
ACCEPT     all  --  0.0.0.0/0            0.0.0.0/0           

[...]

Chain libvirt-out (1 references)
target     prot opt source               destination         
FO-vnet0   all  --  0.0.0.0/0            0.0.0.0/0           [goto]  PHYSDEV match --physdev-out vnet0



The reason is that the recent nwfilter code only removed filtering rules in
the libvirt-out chain that contain the --physdev-is-bridged parameter.
Older rules didn't match and were not removed.

Note that the user-defined chain FO-vnet0 could not be removed due to the
reference from the rule in libvirt-out.

Often the work around may be done through

service iptables restart
kill -SIGHUP $(pidof libvirtd)

This patch now also removes older libvirt versions' iptables rules.
Signed-off-by: NStefan Berger <stefanb@linux.vnet.ibm.com>

Testing our backing chain handling will make it much easier to
ensure that we avoid issues in the future.  If only I had written
this test before I first caused several regressions...

* tests/virstoragetest.c: New test.
* tests/Makefile.am (test_programs): Build it.
* .gitignore: Ignore new files.

If you have a qcow2 file /path1/to/file pointed to by symlink
/path2/symlink, and pass qemu /path2/symlink, then qemu treats
a relative backing file in the qcow2 metadata as being relative
to /path2, not /path1/to.  Yes, this means that it is possible
to create a qcow2 file where the choice of WHICH directory and
symlink you access its contents from will then determine WHICH
backing file (if any) you actually find; the results can be
rather screwy, but we have to match what qemu does.

Libvirt and qemu default to creating absolute backing file
names, so most users don't hit this.  But at least VDSM uses
symlinks and relative backing names alongside the
--reuse-external flags to libvirt snapshot operations, with the
result that libvirt was failing to follow the intended chain of
backing files, and then backing files were not granted the
necessary sVirt permissions to be opened by qemu.

See https://bugzilla.redhat.com/show_bug.cgi?id=903248 for
more gory details.  This fixes a regression introduced in
commit 82507838.

I tested this patch by creating the following chain:

ls /home/eblake/Downloads/Fedora.iso # raw file for base
cd /var/lib/libvirt/images
qemu-img create -f qcow2 \
  -obacking_file=/home/eblake/Downloads/Fedora.iso,backing_fmt=raw one
mkdir sub
cd sub
ln -s ../one onelink
qemu-img create -f qcow2 \
  -obacking_file=../sub/onelink,backing_fmt=qcow2 two
mv two ..
ln -s ../two twolink
qemu-img create -f qcow2 \
  -obacking_file=../sub/twolink,backing_fmt=qcow2 three
mv three ..
ln -s ../three threelink

then pointing my domain at /var/lib/libvirt/images/sub/threelink.
Prior to this patch, I got complaints about missing backing
files; afterwards, I was able to verify that the backing chain
(and hence DAC and SELinux relabels) of the entire chain worked.

* src/util/virstoragefile.h (_virStorageFileMetadata): Add
directory member.
* src/util/virstoragefile.c (absolutePathFromBaseFile): Drop,
replaced by...
(virFindBackingFile): ...better function.
(virStorageFileGetMetadataInternal): Add an argument.
(virStorageFileGetMetadataFromFD, virStorageFileChainLookup)
(virStorageFileGetMetadata): Update callers.

Prior to this patch, we had the callchains:
external users
  \-> virStorageFileGetMetadataFromFD
      \-> virStorageFileGetMetadataFromBuf
virStorageFileGetMetadataRecurse
  \-> virStorageFileGetMetadataFromFD
      \-> virStorageFileGetMetadataFromBuf

However, a future patch wants to add an additional parameter to
the bottom of the chain, for use by virStorageFileGetMetadataRecurse,
without affecting existing external callers.  Since there is only a
single caller of the internal function, we can repurpose it to fit
our needs, with this patch giving us:

external users
  \-> virStorageFileGetMetadataFromFD
      \-> virStorageFileGetMetadataInternal
virStorageFileGetMetadataRecurse /
  \-> virStorageFileGetMetadataInternal

* src/util/virstoragefile.c (virStorageFileGetMetadataFromFD):
Move most of the guts...
(virStorageFileGetMetadataFromBuf): ...here, and rename...
(virStorageFileGetMetadataInternal): ...to this.
(virStorageFileGetMetadataRecurse): Use internal helper.

virStorageFileGetMetadataFromFD is the only caller of
virStorageFileGetMetadataFromBuf; and it doesn't care about the
difference between a return of 0 (total success) or 1
(metadata was inconsistent, but pointer was populated as best
as possible); only about a return of -1 (could not read metadata
or out of memory).  Changing the return type, and normalizing
the variable names used, will make merging the functions easier
in the next commit.

* src/util/virstoragefile.c (virStorageFileGetMetadataFromBuf):
Change return value, and rename some variables.
(virStorageFileGetMetadataFromFD): Rename some variables.

No semantic change; done so the next patch doesn't need a forward
declaration of a static function.

* src/util/virstoragefile.c (virStorageFileProbeFormatFromBuf):
Hoist earlier.

More mingw build failures:

  CCLD     libvirt-lxc.la
/usr/lib64/gcc/i686-w64-mingw32/4.7.2/../../../../i686-w64-mingw32/bin/ld: cannot find libvirt_lxc.def: No such file or directory

  CC       virportallocatortest-virportallocatortest.o
../../tests/virportallocatortest.c: In function 'main':
../../tests/virportallocatortest.c:195:1: error: implicit declaration of function 'setenv' [-Werror=implicit-function-declaration]

* src/Makefile.am (GENERATED_SYM_FILES): Also generate
libvirt_lxc.def.
* bootstrap.conf (gnulib_modules): Import setenv.