1 files changed, 148 insertions, 0 deletions
diff --git a/hw/s390x/css-bridge.c b/hw/s390x/css-bridge.c
new file mode 100644
index 0000000000..9a7f7ee60c
--- /dev/null
+++ b/hw/s390x/css-bridge.c
@@ -0,0 +1,148 @@
+/*
+ * css bridge implementation
+ *
+ * Copyright 2012,2016 IBM Corp.
+ * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
+ *            Pierre Morel <pmorel@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or (at
+ * your option) any later version. See the COPYING file in the top-level
+ * directory.
+ */
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "hw/hotplug.h"
+#include "hw/sysbus.h"
+#include "qemu/bitops.h"
+#include "hw/s390x/css.h"
+#include "ccw-device.h"
+#include "hw/s390x/css-bridge.h"
+
+/*
+ * Invoke device-specific unplug handler, disable the subchannel
+ * (including sending a channel report to the guest) and remove the
+ * device from the virtual css bus.
+ */
+static void ccw_device_unplug(HotplugHandler *hotplug_dev,
+                              DeviceState *dev, Error **errp)
+{
+    CcwDevice *ccw_dev = CCW_DEVICE(dev);
+    CCWDeviceClass *k = CCW_DEVICE_GET_CLASS(ccw_dev);
+    SubchDev *sch = ccw_dev->sch;
+    Error *err = NULL;
+
+    if (k->unplug) {
+        k->unplug(hotplug_dev, dev, &err);
+        if (err) {
+            error_propagate(errp, err);
+            return;
+        }
+    }
+
+    /*
+     * We should arrive here only for device_del, since we don't support
+     * direct hot(un)plug of channels.
+     */
+    assert(sch != NULL);
+    /* Subchannel is now disabled and no longer valid. */
+    sch->curr_status.pmcw.flags &= ~(PMCW_FLAGS_MASK_ENA |
+                                     PMCW_FLAGS_MASK_DNV);
+
+    css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, 1, 0);
+
+    object_unparent(OBJECT(dev));
+}
+
+static void virtual_css_bus_reset(BusState *qbus)
+{
+    /* This should actually be modelled via the generic css */
+    css_reset();
+}
+
+static char *virtual_css_bus_get_dev_path(DeviceState *dev)
+{
+    CcwDevice *ccw_dev = CCW_DEVICE(dev);
+    SubchDev *sch = ccw_dev->sch;
+    VirtualCssBridge *bridge =
+        VIRTUAL_CSS_BRIDGE(qdev_get_parent_bus(dev)->parent);
+
+    /*
+     * We can't provide a dev path for backward compatibility on
+     * older machines, as it is visible in the migration stream.
+     */
+    return bridge->css_dev_path ?
+        g_strdup_printf("/%02x.%1x.%04x", sch->cssid, sch->ssid, sch->devno) :
+        NULL;
+}
+
+static void virtual_css_bus_class_init(ObjectClass *klass, void *data)
+{
+    BusClass *k = BUS_CLASS(klass);
+
+    k->reset = virtual_css_bus_reset;
+    k->get_dev_path = virtual_css_bus_get_dev_path;
+}
+
+static const TypeInfo virtual_css_bus_info = {
+    .name = TYPE_VIRTUAL_CSS_BUS,
+    .parent = TYPE_BUS,
+    .instance_size = sizeof(VirtualCssBus),
+    .class_init = virtual_css_bus_class_init,
+};
+
+VirtualCssBus *virtual_css_bus_init(void)
+{
+    VirtualCssBus *cbus;
+    BusState *bus;
+    DeviceState *dev;
+
+    /* Create bridge device */
+    dev = qdev_create(NULL, TYPE_VIRTUAL_CSS_BRIDGE);
+    qdev_init_nofail(dev);
+
+    /* Create bus on bridge device */
+    bus = qbus_create(TYPE_VIRTUAL_CSS_BUS, dev, "virtual-css");
+    cbus = VIRTUAL_CSS_BUS(bus);
+
+    /* Enable hotplugging */
+    qbus_set_hotplug_handler(bus, dev, &error_abort);
+
+    return cbus;
+ }
+
+/***************** Virtual-css Bus Bridge Device ********************/
+
+static Property virtual_css_bridge_properties[] = {
+    DEFINE_PROP_BOOL("css_dev_path", VirtualCssBridge, css_dev_path,
+                     true),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void virtual_css_bridge_class_init(ObjectClass *klass, void *data)
+{
+    HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+
+    hc->unplug = ccw_device_unplug;
+    set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
+    dc->props = virtual_css_bridge_properties;
+}
+
+static const TypeInfo virtual_css_bridge_info = {
+    .name          = TYPE_VIRTUAL_CSS_BRIDGE,
+    .parent        = TYPE_SYS_BUS_DEVICE,
+    .instance_size = sizeof(VirtualCssBridge),
+    .class_init    = virtual_css_bridge_class_init,
+    .interfaces = (InterfaceInfo[]) {
+        { TYPE_HOTPLUG_HANDLER },
+        { }
+    }
+};
+
+static void virtual_css_register(void)
+{
+    type_register_static(&virtual_css_bridge_info);
+    type_register_static(&virtual_css_bus_info);
+}
+
+type_init(virtual_css_register)