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  50     /* Subchannel is now disabled and no longer valid.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