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  48     /* Subchannel is now disabled and no longer valid.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     qdev_init_nofail(dev);
 103
 104     /* Create bus on bridge device */
 105     bus = qbus_create(TYPE_VIRTUAL_CSS_BUS, dev, "virtual-css");
 106     cbus = VIRTUAL_CSS_BUS(bus);
 107     cbus->squash_mcss = s390_get_squash_mcss();
 108
 109     /* Enable hotplugging */
 110     qbus_set_hotplug_handler(bus, dev, &error_abort);
 111
 112     css_register_io_adapters(CSS_IO_ADAPTER_VIRTIO, true, false,
 113                              0, &error_abort);
 114
 115     return cbus;
 116  }
 117
 118 /***************** Virtual-css Bus Bridge Device ********************/
 119
 120 static Property virtual_css_bridge_properties[] = {
 121     DEFINE_PROP_BOOL("css_dev_path", VirtualCssBridge, css_dev_path,
 122                      true),
 123     DEFINE_PROP_END_OF_LIST(),
 124 };
 125
 126 static bool prop_get_true(Object *obj, Error **errp)
 127 {
 128     return true;
 129 }
 130
 131 static void virtual_css_bridge_class_init(ObjectClass *klass, void *data)
 132 {
 133     HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass);
 134     DeviceClass *dc = DEVICE_CLASS(klass);
 135
 136     hc->unplug = ccw_device_unplug;
 137     set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories);
 138     dc->props = virtual_css_bridge_properties;
 139     object_class_property_add_bool(klass, "cssid-unrestricted",
 140                                    prop_get_true, NULL, NULL);
 141     object_class_property_set_description(klass, "cssid-unrestricted",
 142             "A css device can use any cssid, regardless whether virtual"
 143             " or not (read only, always true)",
 144             NULL);
 145 }
 146
 147 static const TypeInfo virtual_css_bridge_info = {
 148     .name          = TYPE_VIRTUAL_CSS_BRIDGE,
 149     .parent        = TYPE_SYS_BUS_DEVICE,
 150     .instance_size = sizeof(VirtualCssBridge),
 151     .class_init    = virtual_css_bridge_class_init,
 152     .interfaces = (InterfaceInfo[]) {
 153         { TYPE_HOTPLUG_HANDLER },
 154         { }
 155     }
 156 };
 157
 158 static void virtual_css_register(void)
 159 {
 160     type_register_static(&virtual_css_bridge_info);
 161     type_register_static(&virtual_css_bus_info);
 162 }
 163
 164 type_init(virtual_css_register)