The S390 virtual css support already has a mechanism to create a
virtual subchannel and provide it to the guest. However, to
pass-through subchannels to a guest, we need to introduce a new
mechanism to create the subchannel according to the real device
information. Thus we reconstruct css_create_virtual_sch to a new
css_create_sch function to handle all these cases and do allocation
and initialization of the subchannel according to the device type
and machine configuration.
Reviewed-by: NPierre Morel <pmorel@linux.vnet.ibm.com>
Signed-off-by: NDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Message-Id: <20170517004813.58227-6-bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

The I/O adapters should exist as soon as the bus/infrastructure
exists, and not only when the guest is actually trying to do something
with them. While the lazy allocation was not wrong, allocating at init
time is cleaner, both for the architecture and the code. Let's adjust
this by having each device type (currently for PCI and virtio-ccw)
register the adapters for each ISC (as now we don't know which ISC the
guest will use) as soon as it initializes.

Use a two-dimensional array io_adapters[type][isc] to store adapters
in ChannelSubSys, so that we can conveniently get the adapter id by
the helper function css_get_adapter_id(type, isc).
Signed-off-by: NFei Li <sherrylf@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

We need to implement the get_dev_path method for the css bus, or
else we might end up with two different devices having the same
qdev_path.

This was noticed when adding two scsi_hd controllers: The SCSIBus
code will produce a non-unique dev_path for vmstate usage if the
parent bus does not provide the get_dev_path method.

We simply use the device's bus id, as this is unique and we won't
have any deeper hierarchy from a channel subsystem perspective
anyway.

Note that we need to disable this for older machine versions,
as this changes the migration format.
Reported-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Reviewed-by: NHalil Pasic <pasic@linux.vnet.ibm.com>
Reviewed-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Tested-by: NMarc Hartmayer <mhartmay@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

The previous patch moved virtual css bridge and bus out from
virtio-ccw, but kept the direct reference of virtio-ccw specific
unplug function inside css-bridge.c.

To make the virtual css bus and bridge useful for non-virtio devices,
this introduces a common unplug function pointer "unplug" to call
specific virtio-ccw unplug parts. Thus, the tight coupling to
virtio-ccw can be removed.

This unplug pointer is a member of CCWDeviceClass, which is introduced
as an abstract device layer called "ccw-device". This layer is between
DeviceState and specific devices which are plugged in virtual css bus,
like virtio-ccw device. The specific unplug handlers should be assigned
to "unplug" during initialization.
Signed-off-by: NJing Liu <liujbjl@linux.vnet.ibm.com>
Reviewed-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Reviewed-by: NYi Min Zhao <zyimin@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>

Currently, common base layers virtual css bridge and bus are
defined in hw/s390x/virtio-ccw.c(h). In order to support
multiple types of devices in the virtual channel subsystem,
especially non virtio-ccw, refactoring work needs to be done.

This work is just a pure code move without any functional change
except dropping an empty function virtual_css_bridge_init() and
virtio_ccw_busdev_unplug() changing. virtio_ccw_busdev_unplug()
is specific to virtio-ccw but gets referenced from the common
virtual css bridge code. To keep the functional changes to a
minimum we export this function from virtio-ccw.c and continue
to reference it inside virtual_css_bridge_class_init()
(now living in hw/s390x/css-bridge.c). A follow-up patch will
clean this up.
Signed-off-by: NJing Liu <liujbjl@linux.vnet.ibm.com>
Reviewed-by: NSascha Silbe <silbe@linux.vnet.ibm.com>
Reviewed-by: NDong Jia Shi <bjsdjshi@linux.vnet.ibm.com>
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>