The functions
- iptablesAddForwardDontMasquerade(),
- iptablesRemoveForwardDontMasquerade
handle exceptions in the masquerading implemented in the POSTROUTING chain
of the "nat" table. Such exceptions should be added as chronologically
latest, logically top-most rules.
The bridge driver will call these functions beginning with the next patch:
some special destination IP addresses always refer to the local
subnetwork, even though they don't match any practical subnetwork's
netmask. Packets from virbrN targeting such IP addresses are never routed
outwards, but the current rules treat them as non-virbrN-destined packets
and masquerade them. This causes problems for some receivers on virbrN.
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
To allow creation of a virNetSocketPtr instance from a pre-opened
socketpair FD, add a virNetSocketNewConnectSockFD method.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The virDomainGetMetadata function was designed to support also retrieval
of app specific metadata from the <metadata> element. This functionality
was never implemented originally.
The function implemented common behavior that can be reused for other
hypervisor drivers that use the virDomainObj data structures. Factor out
the core into a separate helper func.
The function implemented common behavior that can be reused for other
hypervisor drivers that use the virDomainObj data structures. Factor out
the core into a separate helper func.
When using a <interface type="network"> that points to a network with
hostdev forwarding mode a hostdev alias is created for the network. This
allias is inserted into the hostdev list, but is backed with a part of
the network object that it is connected to.
When a VM is being stopped qemuProcessStop() calls
networkReleaseActualDevice() which eventually frees the memory for the
hostdev object. Afterwards when the domain definition is being freed by
virDomainDefFree() an invalid pointer is accessed by
virDomainHostdevDefFree() and may cause a crash of the daemon.
This patch removes the entry in the hostdev list before freeing the
depending memory to avoid this issue.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1000973
Some systems may not use DBus in their system. Add a method to check if
the system bus is available that doesn't print error messages so that
code can later check for this condition and use an alternative approach.
*src/util/virstoragefile.c: Add a helper function to get
the first name of missing backing files, if the name is NULL,
it means the diskchain is not broken.
*src/qemu/qemu_domain.c: qemuDiskChainCheckBroken(disk) to
check if its chain is broken
There are some interesting escaping rules to consider when dealing
with systemd slice/scope names. Thus it is helpful to have APIs
for formatting names
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This function is needed for virt-login-shell. Also modify virGirUserDirectory
to use the new function, to simplify the code.
Signed-off-by: Eric Blake <eblake@redhat.com>
The virCgroupIsValidMachine does not need to be called from
outside the cgroups file now, so make it static.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of requiring drivers to use a combination of calls
to virCgroupNewDetect and virCgroupIsValidMachine, combine
the two into virCgroupNewDetectMachine
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Instead of requiring one API call to create a cgroup and
another to add a task to it, introduce a new API
virCgroupNewMachine which does both jobs at once. This
will facilitate the later code to talk to systemd to
achieve this job which is also atomic.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Parsing 'user:group' is useful even outside the DAC security driver,
so expose the most abstract function which has no DAC security driver
bits in itself.
Since PCI bridges, PCIe bridges, PCIe switches, and PCIe root ports
all share the same namespace, they are all defined as controllers of
type='pci' in libvirt (but with a differing model attribute). Each of
these controllers has a certain connection type upstream, allows
certain connection types downstream, and each can either allow a
single downstream connection at slot 0, or connections from slot 1 -
31.
Right now, we only support the pci-root and pci-bridge devices, both
of which only allow PCI devices to connect, and both which have usable
slots 1 - 31. In preparation for adding other types of controllers
that have different capabilities, this patch 1) adds info to the
qemuDomainPCIAddressBus object to indicate the capabilities, 2) sets
those capabilities appropriately for pci-root and pci-bridge devices,
and 3) validates that the controller being connected to is the proper
type when allocating slots or validating that a user-selected slot is
appropriate for a device..
Having this infrastructure in place will make it much easier to add
support for the other PCI controller types.
While it would be possible to do all the necessary checking by just
storing the controller model in the qemyuDomainPCIAddressBus, it
greatly simplifies all the validation code to also keep a "flags",
"minSlot" and "maxSlot" for each - that way we can just check those
attributes rather than requiring a nearly identical switch statement
everywhere we need to validate compatibility.
You may notice many places where the flags are seemingly hard-coded to
QEMU_PCI_CONNECT_HOTPLUGGABLE | QEMU_PCI_CONNECT_TYPE_PCI
This is currently the correct value for all PCI devices, and in the
future will be the default, with small bits of code added to change to
the flags for the few devices which are the exceptions to this rule.
Finally, there are a few places with "FIXME" comments. Note that these
aren't indicating places that are broken according to the currently
supported devices, they are places that will need fixing when support
for new PCI controller models is added.
To assure that there was no regression in the auto-allocation of PCI
addresses or auto-creation of integrated pci-root, ide, and usb
controllers, a new test case (pci-bridge-many-disks) has been added to
both the qemuxml2argv and qemuxml2xml tests. This new test defines a
domain with several dozen virtio disks but no pci-root or
pci-bridges. The .args file of the new test case was created using
libvirt sources from before this patch, and the test still passes
after this patch has been applied.
The virCgroupNewDomainDriver and virCgroupNewDriver methods
are obsolete now that we can auto-detect existing cgroup
placement. Delete them to reduce code bloat.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add virCgroupIsValidMachine API to check whether an auto
detected cgroup is valid for a machine. This lets us
check if a VM has just been placed into some generic
shared cgroup, or worse, the root cgroup
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add a virCgroupNewDetect API which is used to initialize a
cgroup object with the placement of an arbitrary process.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add virErrorSetErrnoFromLastError and virLastErrorIsSystemErrno
to simplify code which wants to handle system errors in a more
graceful fashion.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
To register virtual machines and containers with systemd-machined,
and thus have cgroups auto-created, we need to talk over DBus.
This is somewhat tedious code, so introduce a dedicated function
to isolate the DBus call in one place.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Doing DBus method calls using libdbus.so is tedious in the
extreme. systemd developers came up with a nice high level
API for DBus method calls (sd_bus_call_method). While
systemd doesn't use libdbus.so, their API design can easily
be ported to libdbus.so.
This patch thus introduces methods virDBusCallMethod &
virDBusMessageRead, which are based on the code used for
sd_bus_call_method and sd_bus_message_read. This code in
systemd is under the LGPLv2+, so we're license compatible.
This code is probably pretty unintelligible unless you are
familiar with the DBus type system. So I added some API
docs trying to explain how to use them, as well as test
cases to validate that I didn't screw up the adaptation
from the original systemd code.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
These helpers use the remembered host capabilities to retrieve the cpu
map rather than query the host again. The intended usage for this
helpers is to fix automatic NUMA placement with strict memory alloc. The
code doing the prepare needs to pin the emulator process only to cpus
belonging to a subset of NUMA nodes of the host.
Merge the virCommandPreserveFD / virCommandTransferFD methods
into a single virCommandPasFD method, and use a new
VIR_COMMAND_PASS_FD_CLOSE_PARENT to indicate their difference
in behaviour
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
There are two levels on which a device may be hotplugged: config
and live. The config level requires just an insert or remove from
internal domain definition structure, which is exactly what this
patch does. There is currently no implementation for a chardev
update action, as there's not much to be updated. But more
importantly, the only thing that can be updated is path or socket
address by which chardevs are distinguished. So the update action
is currently not supported.
This new function updates or adds a feature to a existing cpu model
definition. This function will be helpful to allow tuning of
"host-model" features in later patches.
For now, only these three helpers are needed:
virDomainChrFind - to find a duplicate chardev within VM def
virDomainChrInsert - wrapper for inserting a new chardev into VM def
virDomainChrRemove - wrapper for removing chardev from VM def
There is, however, one internal helper as well:
virDomainChrGetDomainPtrs which sets given pointers to one of
vmdef->{parallels,serials,consoles,channels} based on passed
chardev type.
Since neither getpwuid_r() nor initgroups() are safe to call in
between fork and exec (they obtain a mutex, but if some other
thread in the parent also held the mutex at the time of the fork,
the child will deadlock), we have to split out the functionality
that is unsafe. At least glibc's initgroups() uses getgrouplist
under the hood, so the ideal split is to expose getgrouplist for
use before a fork. Gnulib already gives us a nice wrapper via
mgetgroups; we wrap it once more to look up by uid instead of name.
* bootstrap.conf (gnulib_modules): Add mgetgroups.
* src/util/virutil.h (virGetGroupList): New declaration.
* src/util/virutil.c (virGetGroupList): New function.
* src/libvirt_private.syms (virutil.h): Export it.
Signed-off-by: Eric Blake <eblake@redhat.com>
Actually, I'm turning this function into a macro as filename,
function name and line number needs to be passed. The new
function virAsprintfInternal is introduced with the extended set
of arguments.
While iterating with virDomainObjListForEach it is safe to remove
current element. But while iterating, 'doms' lock is already taken, so
can't use standard virDomainObjListRemove. So introduce
virDomainObjListRemoveLocked for this purpose.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
Ensure that all APIs which list node device objects filter
them against the access control system.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
iptablesContext holds only 4 pairs of iptables
(table, chain) and there's no need to pass
it around.
This is a first step towards separating bridge_driver.c
in platform-specific parts.
Any device which belongs to an "IOMMU group" (used by vfio) will
have links to all devices of its group listed in
/sys/bus/pci/$device/iommu_group/devices;
/sys/bus/pci/$device/iommu_group is actually a link to
/sys/kernel/iommu_groups/$n, where $n is the group number (there
will be a corresponding device node at /dev/vfio/$n once the
devices are bound to the vfio-pci driver)
The following functions are added:
virPCIDeviceGetIOMMUGroupList
Gets a virPCIDeviceList with one virPCIDeviceList for each device
in the same IOMMU group as the provided virPCIDevice (a copy of the
original device object is included in the list.
virPCIDeviceAddressIOMMUGroupIterate
Calls the function @actor once for each device in the group that
contains the given virPCIDeviceAddress.
virPCIDeviceAddressGetIOMMUGroupAddresses
Fills in a virPCIDeviceAddressPtr * with an array of
virPCIDeviceAddress, one for each device in the iommu group of the
provided virPCIDeviceAddress (including a copy of the original).
virPCIDeviceAddressGetIOMMUGroupNum
Returns the group number as an int (a valid group number will always
be 0 or greater). If there is no iommu_group link in the device's
directory (usually indicating that vfio isn't loaded), -2 will be
returned. On any real error, -1 will be returned.
I realized after the fact that it's probably better in the long run to
give this function a name that matches the name of the link used in
sysfs to hold the group (iommu_group).
I'm changing it now because I'm about to add several more functions
that deal with iommu groups.
All APIs that take typed parameters are only using params address in
their entry point debug messages. With the new VIR_TYPED_PARAMS_DEBUG
macro, all functions can easily log all individual typed parameters
passed to them.
* virPCIDeviceFindByIDs - find a device on a list w/o creating an object
This makes searching for an existing device on a list lighter weight.
* virPCIDeviceCopy - make a copy of an existing virPCIDevice object.
* virPCIDeviceGetDriverPathAndName - construct new strings containing
1) the name of the driver bound to this device.
2) the full path to the sysfs config for that driver.
(This code was lifted from virPCIDeviceUnbindFromStub, and replaced
there with a call to this new function).
Add a new 'access_drivers' config parameter to the libvirtd.conf
configuration file. This allows admins to setup the default
access control drivers to use for API authorization. The same
driver is to be used by all internal drivers & APIs
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This patch introduces the virAccessManagerPtr class as the
interface between virtualization drivers and the access
control drivers. The viraccessperm.h file defines the
various permissions that will be used for each type of object
libvirt manages
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Add <features> and <compat> elements to volume target XML.
<compat> is a string which for qcow2 represents the QEMU version
it should be compatible with. Valid values are 0.10 and 1.1.
1.1 is implicit if the <features> element is present, otherwise
qemu-img default is used. 0.10 can be specified to explicitly
create older images after the qemu-img default changes.
<features> contains optional features, so far
<lazy_refcounts/> is available, which enables caching of reference
counters, improving performance for snapshots.
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
We can't use GNULIB's fprintf-posix due to licensing
incompatibilities. We do already have a portable
formatting via virAsprintf() which we got from GNULIB
though. We can use to create a virFilePrintf() function.
But really gnulib could just provide a 'fprintf'
module, that depended on just its 'asprintf' module.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
-vnc :5900,share=allow-exclusive
allows clients to ask for exclusive access which is
implemented by dropping other connections Connecting
multiple clients in parallel requires all clients asking
for a shared session (vncviewer: -shared switch)
-vnc :5900,share=force-shared
disables exclusive client access. Useful for shared
desktop sessions, where you don't want someone forgetting
specify -shared disconnect everybody else.
-vnc :5900,share=ignore
completely ignores the shared flag and allows everybody
connect unconditionally
Introduce use of a virDomainDefPtr in the domain lookup
APIs to simplify introduction of ACL security checks.
The virDomainPtr cannot be safely used, since the app
may have supplied mis-matching name/uuid/id fields. eg
the name points to domain X, while the uuid points to
domain Y. Resolving the virDomainPtr to a virDomainDefPtr
ensures a consistent name/uuid/id set.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
QEMU introduced "discard" option for drive since commit a9384aff53,
<...>
@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and
controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap})
requests are ignored or passed to the filesystem. Some machine types
may not support discard requests.
</...>
This patch exposes the support in libvirt.
QEMU supported "discard" for "-drive" since v1.5.0-rc0:
% git tag --contains a9384aff53
contains
v1.5.0-rc0
v1.5.0-rc1
So this only detects the capability bit using virQEMUCapsProbeQMPCommandLine.
In an upcoming patch, I need the way to safely transfer a nested
virJSON object out of its parent container for independent use,
even after the parent is freed.
* src/util/virjson.h (virJSONValueObjectRemoveKey): New function.
(_virJSONObject, _virJSONArray): Use correct type.
* src/util/virjson.c (virJSONValueObjectRemoveKey): Implement it.
* src/libvirt_private.syms (virjson.h): Export it.
* tests/jsontest.c (mymain): Test it.
Signed-off-by: Eric Blake <eblake@redhat.com>
network: static route support for <network>
This patch adds the <route> subelement of <network> to define a static
route. the address and prefix (or netmask) attribute identify the
destination network, and the gateway attribute specifies the next hop
address (which must be directly reachable from the containing
<network>) which is to receive the packets destined for
"address/(prefix|netmask)".
These attributes are translated into an "ip route add" command that is
executed when the network is started. The command used is of the
following form:
ip route add <address>/<prefix> via <gateway> \
dev <virbr-bridge> proto static metric <metric>
Tests are done to validate that the input data are correct. For
example, for a static route ip definition, the address must be a
network address and not a host address. Additional checks are added
to ensure that the specified gateway is directly reachable via this
network (i.e. that the gateway IP address is in the same subnet as one
of the IP's defined for the network).
prefix='0' is supported for both family='ipv4' address='0.0.0.0'
netmask='0.0.0.0' or prefix='0', and for family='ipv6' address='::',
prefix=0', although care should be taken to not override a desired
system default route.
Anytime an attempt is made to define a static route which *exactly*
duplicates an existing static route (for example, address=::,
prefix=0, metric=1), the following error message will be sent to
syslog:
RTNETLINK answers: File exists
This can be overridden by decreasing the metric value for the route
that should be preferred, or increasing the metric for the route that
shouldn't be preferred (and is thus in place only in anticipation that
the preferred route may be removed in the future). Caution should be
used when manipulating route metrics, especially for a default route.
Note: The use of the command-line interface should be replaced by
direct use of libnl so that error conditions can be handled better. But,
that is being left as an exercise for another day.
Signed-off-by: Gene Czarcinski <gene@czarc.net>
Signed-off-by: Laine Stump <laine@laine.org>
Add a virFileNBDDeviceAssociate method, which given a filename
will setup a NBD device, using qemu-nbd as the server.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Currently the fdstream function hardcodes the location
of the iohelper to LIBEXECDIR "/libvirt_iohelper". This
is not convenient when trying to write test cases which
use this code. Add a virFDStreamSetIOHelper method to
allow the test cases to point to the location of the
un-installed iohelper binary.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
These all existed before virfile.c was created, and for some reason
weren't moved.
This is mostly straightfoward, although the syntax rule prohibiting
write() had to be changed to have an exception for virfile.c instead
of virutil.c.
This movement pointed out that there is a function called
virBuildPath(), and another almost identical function called
virFileBuildPath(). They really should be a single function, which
I'll take care of as soon as I figure out what the arglist should look
like.
Since PIDs can be reused, polkit prefers to be given
a (PID,start time) pair. If given a PID on its own,
it will attempt to lookup the start time in /proc/pid/stat,
though this is subject to races.
It is safer if the client app resolves the PID start
time itself, because as long as the app has the client
socket open, the client PID won't be reused.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
There are various methods named "virXXXXSecurityContext",
which are specific to SELinux. Rename them all to
"virXXXXSELinuxContext". They will still raise errors at
runtime if SELinux is not compiled in
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
The code adaptation is not done right now, but in subsequent patches.
Hence I am not implementing syntax-check rule as it would break
compilation. Developers are strongly advised to use these new macros.
They are similar to VIR_ALLOC() logic: VIR_STRDUP(dst, src) returns zero
on success, -1 otherwise. In case you don't want to report OOM error,
use the _QUIET variant of a macro.
The source code base needs to be adapted as well. Some files
include virutil.h just for the string related functions (here,
the include is substituted to match the new file), some include
virutil.h without any need (here, the include is removed), and
some require both.
This will be used on a tap file descriptor returned by the bridge helper
to populate the <target> element, because the helper does not provide
the interface name.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This patch adds two sets of functions:
1) lower level virProcessSet*() functions that will immediately set
the RLIMIT_MEMLOCK. RLIMIT_NPROC, or RLIMIT_NOFILE of either the
current process (using setrlimit()) or any other process (using
prlimit()). "current process" is indicated by passing a 0 for pid.
2) functions for virCommand* that will setup a virCommand object to
set those limits at a later time just after it has forked a new
process, but before it execs the new program.
configure.ac has prlimit and setrlimit added to the list of functions
to check for, and the low level functions log an "unsupported" error)
on platforms that don't support those functions.
This can be set when the virPCIDevice is created and placed on a list,
then used later when traversing the list to determine which stub
driver to bind/unbind for managed devices.
The existing Detach and Attach functions' signatures haven't been
changed (they still accept a stub driver name in the arg list), but if
the arg list has NULL for stub driver and one is available in the
device's object, that will be used. (we may later deprecate and remove
the arg from those functions).
<controller type='pci' index='0' model='pci-root'/>
is auto-added to pc* machine types.
Without this controller PCI bus 0 is not available and
no PCI addresses are assigned by default.
Since older libvirt supported PCI bus 0 even without
this controller, it is removed from the XML when migrating.
Now we set the default disk driver name when parsing
the qemu command line too, hence all the test changes.
Assume format type is 'auto' when none is specified on
qemu command line.
The driver.h struct for node devices used an inconsistent
naming scheme 'DeviceMonitor' instead of the more usual
'NodeDeviceDriver'. Fix this everywhere it has leaked
out to.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Ensure that the driver struct field names match the public
API names. For an API virXXXX we must have a driver struct
field xXXXX. ie strip the leading 'vir' and lowercase any
leading uppercase letters.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Refactoring done in 19c6ad9ac7 didn't
correctly take into account the order cgroup limit modification needs to
be done in. This resulted into errors when decreasing the limits.
The operations need to take place in this order:
decrease hard limit
change swap hard limit
or
change swap hard limit
increase hard limit
This patch also fixes the check if the hard_limit is less than
swap_hard_limit to print better error messages. For this purpose I
introduced a helper function virCompareLimitUlong to compare limit
values where value of 0 is equal to unlimited. Additionally the check is
now applied also when the user does not provide all of the tunables
through the API and in that case the currently set values are used.
This patch resolves:
https://bugzilla.redhat.com/show_bug.cgi?id=950478
Create the utility function virSocketAddrGetIpPrefix() to
determine the prefix for this network. The code in this
function was adapted from virNetworkIpDefPrefix().
Update virNetworkIpDefPrefix() in src/conf/network_conf.c
to use the new utility function.
Signed-off-by: Gene Czarcinski <gene@czarc.net>
Until now tranisent networks weren't really useful as libvirtd wasn't
able to remember them across restarts. This patch adds support for
loading status files of transient networks (that already were generated)
so that the status isn't lost.
This patch chops up virNetworkObjUpdateParseFile and turns it into
virNetworkLoadState and a few friends that will help us to load status
XMLs and refactors the functions that are loading the configs to use
them.
Add a virCgroupIsolateMount method which looks at where the
current process is place in the cgroups (eg /system/demo.lxc.libvirt)
and then remounts the cgroups such that this sub-directory
becomes the root directory from the current process' POV.
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
A resource partition is an absolute cgroup path, ignoring the
current process placement. Expose a virCgroupNewPartition API
for constructing such cgroups
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Rename all the virCgroupForXXX methods to use the form
virCgroupNewXXX since they are all constructors. Also
make sure the output parameter is the last one in the
list, and annotate all pointers as non-null. Fix up
all callers, and make sure they use true/false not 0/1
for the boolean parameters
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Parse the domain XML with TPM passthrough support.
The TPM passthrough XML may look like this:
<tpm model='tpm-tis'>
<backend type='passthrough'>
<device path='/dev/tpm0'/>
</backend>
</tpm>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
Tested-by: Corey Bryant <coreyb@linux.vnet.ibm.com>
The helper function to look up disk controller model may be used by scsi
hostdev. But it should be changed to use device info.
Signed-off-by: Han Cheng <hanc.fnst@cn.fujitsu.com>
The virCgroupMounted method is badly named, since a controller can be
mounted, but disabled in the current object. Rename the method to be
virCgroupHasController. Also make it tolerant to a NULL virCgroupPtr
and out-of-range controller index, to avoid duplication of these
checks in all callers
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
This finds the parent for vHBA by iterating over all the HBA
which supports vport_ops capability on the host, and return
the first one which is online, not saturated (vports in use
is less than max_vports).
The helper iterates over sysfs, to find out the matched scsi host
name by comparing the wwnn,wwpn pair. It will be used by checkPool
and refreshPool of storage scsi backend. New helper getAdapterName
is introduced in storage_backend_scsi.c, which uses the new util
helper virGetFCHostNameByWWN to get the fc_host adapter name.