https://bugzilla.redhat.com/show_bug.cgi?id=1349696

When creating a vHBA, the process is to feed XML to nodeDeviceCreateXML
that lists the <parent> scsi_hostX to use to create the vHBA. However,
between reboots, it's possible that the <parent> changes its scsi_hostX
to scsi_hostY and saved XML to perform the creation will either fail or
create a vHBA using the wrong parent.

So add the ability to provide "wwnn" and "wwpn" or "fabric_wwn" to
the <parent> instead of a name of the scsi_hostN that is the parent.
The allowed XML will thus be:

  <parent>scsi_host3</parent>  (current)

or

  <parent wwnn='$WWNN' wwpn='$WWPN'/>

or

  <parent fabric_wwn='$WWNN'/>

Using the wwnn/wwpn or fabric_wwn ensures the same 'scsi_hostN' is
selected between hardware reconfigs or host reboots. The fabric_wwn
Using the wwnn/wwpn pair will provide the most specific search option,
while fabric_wwn will at least ensure usage of the same SAN, but maybe
not the same scsi_hostN.

This patch will add the new fields to the nodedev.rng for input purposes
only since the input XML is essentially thrown away, no need to Format
the values since they'd already be printed as part of the scsi_host
data block.

New API virNodeDeviceGetParentHostByWWNs will take the parent "wwnn" and
"wwpn" in order to search the list of devices for matching capability
data fields wwnn and wwpn.

New API virNodeDeviceGetParentHostByFabricWWN will take the parent "fabric_wwn"
in order to search the list of devices for matching capability data field
fabric_wwn.

If a <parent> is not supplied in the XML used to create a non-persistent
vHBA, then instead of failing, let's try to find a "vports" capable node
device and use that.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

https://bugzilla.redhat.com/show_bug.cgi?id=1357416

Rather than return a 0 or -1 and the *result string, return just the result
string to the caller.  Alter all the callers to handle the different return.

As a side effect or result of this, it's much clearer that we cannot just
assign the returned string into the scsi_host wwnn, wwpn, and fabric_wwn
fields - rather we should fetch a temporary string, then as long as our
fetch was good, VIR_FREE what may have been there, and STEAL what we just got.
This fixes a memory leak in the virNodeDeviceCreateXML code path through
find_new_device and nodeDeviceLookupSCSIHostByWWN which will continually
call nodeDeviceSysfsGetSCSIHostCaps until the expected wwnn/wwpn is found
in the device object capabilities.
Signed-off-by: NJohn Ferlan <jferlan@redhat.com>

This way we get reference counting and we can get rid of locking
function.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

Test 12 from objecteventtest (createXML add event) segaults on FreeBSD
with bus error.

At some point it calls testNodeDeviceDestroy() from the test driver. And
it fails when it tries to unlock the device in the "out:" label of this
function.

Unlocking fails because the previous step was a call to
virNodeDeviceObjRemove from conf/node_device_conf.c. This function
removes the given device from the device list and cleans up the object,
including destroying of its mutex. However, it does not nullify the pointer
that was given to it.

As a result, we end up in testNodeDeviceDestroy() here:

 out:
    if (obj)
        virNodeDeviceObjUnlock(obj);

And instead of skipping this, we try to do Unlock and fail because of
malformed mutex.

Change virNodeDeviceObjRemove to use double pointer and set pointer to
NULL.

This event is emitted when a nodedev XML definition is updated,
like when cdrom media is changed in a cdrom block device.

Also includes node device update event implementation for udev
backend, virsh nodedev-event support, and event-test support

Filter out some subsystems we are not interested in.

Instead of the custom out and out_unlock.

Remove ret variables and labels from functions where there is no cleanup
to be done.

There is no cleanup to be done.

Remove unnecessary ret variable and return early if we have no media
to save on indentation.

Use virTrimSpaces instead of a custom implementation.

Also use the more common "Unable to initialize mutex" string
and virReportSystemError instead of virStrerror.

They are no longer used.

Open code the call to udev_device_get_sysattr_value
in the one place where it's needed.

Callers only check for an error or a specific integer value.

The callers only care for an error, and a missing attribute
is simply NULL.

Most of the code paths free it right after converting it to
an integer.

We only care about the failure, not a missing property.

There is no need to differentiate between PROPERTY_FOUND
and PROPERTY_MISSING - we can just look if the string is non-NULL.

Error out on parsing errors and use a local const char pointer
instead of chained ifs to check whether we found a match.

Since the switch to VIR_STRDUP this function returns 1 on success,
but the caller treats any non-zero value as failure.

Use udevHasDeviceProperty instead of udevGetStringProperty.
We do not need to copy the string since we do not need it.

Also add braces around the if body, since the change made
syntax check complain.

Two out of three callers free it right after converting it to a number.

Also change the comment at the beginning of the function, because
the comment inside the function told me to.

Open code the error message.

Remove the debug message, open code the error in the two udevGetUint
callers and use a more specific error in SCSI and PCI processing.

The wrapper adds an error message or a debug log.

Since we already log the properties we get from udev as strings,
there is no much use for the debug logs.

Open code the error message and delete the function.

Use virStrToLong_ui instead of udevStrToLong_ui, reformat the code
and report a more specific error message.

Instead of separating it into STRPEFIX and str + strlen.

A variable without use is pointless.

Remove it, since we have no use for it.

If we have not allocated driver yet, there is nothing to cleanup.

Remove the ret variable and return early if there is no driver.

This will simplify cleanup.

Move pci_system_init and pci_system_cleanup into separate functions,
to make the conditional compilation easier to read.