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  48     /* Subchannel is now disabled and no longer valid.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