hw/s390x/css-bridge.c

   1 /*
   2  * css bridge implementation
   3  *
   4  * Copyright 2012,2016 IBM Corp.
   5  * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
   6  *            Pierre Morel <pmorel@linux.vnet.ibm.com>
   7  *
   8  * This work is licensed under the terms of the GNU GPL, version 2 or (at
   9  * your option) any later version. See the COPYING file in the top-level
  10  * directory.
  11  */
  12
  13 #include "qemu/osdep.h"
  14 #include "qapi/error.h"
  15 #include "hw/hotplug.h"
  16 #include "hw/qdev-properties.h"
  17 #include "hw/sysbus.h"
  18 #include "qemu/bitops.h"
  19 #include "qemu/module.h"
  20 #include "hw/s390x/css.h"
  21 #include "ccw-device.h"
  22 #include "hw/s390x/css-bridge.h"
  23 #include "cpu.h"
  24
  25 /*
  26  * Invoke device-specific unplug handler, disable the subchannel
  27  * (including sending a channel report to the guest) and remove the
  28  * device from the virtual css bus.
  29  */
  30 static void ccw_device_unplug(HotplugHandler *hotplug_dev,
  31                               DeviceState *dev, Error **errp)
  32 {
  33     CcwDevice *ccw_dev = CCW_DEVICE(dev);
  34     CCWDeviceClass *k = CCW_DEVICE_GET_CLASS(ccw_dev);
  35     SubchDev *sch = ccw_dev->sch;
  36     Error *err = NULL;
  37
  38     if (k->unplug) {
  39         k->unplug(hotplug_dev, dev, &err);
  40         if (err) {
  41             error_propagate(errp, err);
  42             return;
  43         }
  44     }
  45
  46     /*
  47      * We should arrive here only for device_del, since we don't support
  48      * direct hot(un)plug of channels.
  49      */
  50     assert(sch != NULL);
  51     /* Subchannel is now disabled and no longer valid. */
  52     sch->curr_status.pmcw.flags &= ~(PMCW_FLAGS_MASK_ENA |
  53                                      PMCW_FLAGS_MASK_DNV);
  54
  55     css_generate_sch_crws(sch->cssid, sch->ssid, sch->schid, 1, 0);
  56
  57     qdev_unrealize(dev);
  58 }
  59
  60 static void virtual_css_bus_reset(BusState *qbus)
  61 {
  62     /* This should actually be modelled via the generic css */
  63     css_reset();
  64 }
  65
  66 static char *virtual_css_bus_get_dev_path(DeviceState *dev)
  67 {
  68     CcwDevice *ccw_dev = CCW_DEVICE(dev);
  69     SubchDev *sch = ccw_dev->sch;
  70     VirtualCssBridge *bridge =
  71         VIRTUAL_CSS_BRIDGE(qdev_get_parent_bus(dev)->parent);
  72
  73     /*
  74      * We can't provide a dev path for backward compatibility on
  75      * older machines, as it is visible in the migration stream.
  76      */
  77     return bridge->css_dev_path ?
  78         g_strdup_printf("/%02x.%1x.%04x", sch->cssid, sch->ssid, sch->devno) :
  79         NULL;
  80 }
  81
  82 static void virtual_css_bus_class_init(ObjectClass *klass, void *data)
  83 {
  84     BusClass *k = BUS_CLASS(klass);
  85
  86     k->reset = virtual_css_bus_reset;
  87     k->get_dev_path = virtual_css_bus_get_dev_path;
  88 }
  89
  90 static const TypeInfo virtual_css_bus_info = {
  91     .name = TYPE_VIRTUAL_CSS_BUS,
  92     .parent = TYPE_BUS,
  93     .instance_size = sizeof(VirtualCssBus),
  94     .class_init = virtual_css_bus_class_init,
  95 };
  96
  97 VirtualCssBus *virtual_css_bus_init(void)
  98 {
  99     VirtualCssBus *cbus;
 100     BusState *bus;
 101     DeviceState *dev;
 102
 103     /* Create bridge device */
 104     dev = qdev_new(TYPE_VIRTUAL_CSS_BRIDGE);
 105     object_property_add_child(qdev_get_machine(), TYPE_VIRTUAL_CSS_BRIDGE,
 106                               OBJECT(dev));
 107     sysbus_realize_and_unref(SYS_BUS_DEVICE(dev), &error_fatal);
 108
 109     /* Create bus on bridge device */
 110     bus = qbus_create(TYPE_VIRTUAL_CSS_BUS, dev, "virtual-css");
 111     cbus = VIRTUAL_CSS_BUS(bus);
 112
 113     /* Enable hotplugging */
 114     qbus_set_hotplug_handler(bus, OBJECT(dev));
 115
 116     css_register_io_adapters(CSS_IO_ADAPTER_VIRTIO, true, false,
 117                              0, &error_abort);
 118
 119     return cbus;
 120  }
 121
 122 /***************** Virtual-css Bus Bridge Device ********************/
 123
 124 static Property virtual_css_bridge_properties[] = {
 125     DEFINE_PROP_BOOL("css_dev_path", VirtualCssBridge, css_dev_path,
 126                      true),
 127     DEFINE_PROP_END_OF_LIST(),
 128 };
 129
 130 static bool prop_get_true(Object *obj, Error **errp)
 131 {
 132     return true;
 133 }
 134
 135 static void virtual_css_bridge_class_init(ObjectClass *klass, void *data)
 136 {
 137     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 138     DeviceClass *dc = DEVICE_CLASS(klass);
 139
 140     hc->unplug = ccw_device_unplug;
 141     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 142     device_class_set_props(dc, virtual_css_bridge_properties);
 143     object_class_property_add_bool(klass, "cssid-unrestricted",
 144                                    prop_get_true, NULL);
 145     object_class_property_set_description(klass, "cssid-unrestricted",
 146             "A css device can use any cssid, regardless whether virtual"
 147             " or not (read only, always true)");
 148 }
 149
 150 static const TypeInfo virtual_css_bridge_info = {
 151     .name          = TYPE_VIRTUAL_CSS_BRIDGE,
 152     .parent        = TYPE_SYS_BUS_DEVICE,
 153     .instance_size = sizeof(VirtualCssBridge),
 154     .class_init    = virtual_css_bridge_class_init,
 155     .interfaces = (InterfaceInfo[]) {
 156         { TYPE_HOTPLUG_HANDLER },
 157         { }
 158     }
 159 };
 160
 161 static void virtual_css_register(void)
 162 {
 163     type_register_static(&virtual_css_bridge_info);
 164     type_register_static(&virtual_css_bus_info);
 165 }
 166
 167 type_init(virtual_css_register)