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  47     /* Subchannel is now disabled and no longer valid.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