From 2a79eb1a616a07b0e8c41430f03af254fefe219d Mon Sep 17 00:00:00 2001 From: Cornelia Huck Date: Mon, 11 Jul 2016 12:55:44 +0200 Subject: [PATCH] s390x/css: provide a dev_path for css devices We need to implement the get_dev_path method for the css bus, or else we might end up with two different devices having the same qdev_path. This was noticed when adding two scsi_hd controllers: The SCSIBus code will produce a non-unique dev_path for vmstate usage if the parent bus does not provide the get_dev_path method. We simply use the device's bus id, as this is unique and we won't have any deeper hierarchy from a channel subsystem perspective anyway. Note that we need to disable this for older machine versions, as this changes the migration format. Reported-by: Marc Hartmayer Reviewed-by: Halil Pasic Reviewed-by: Sascha Silbe Tested-by: Marc Hartmayer Signed-off-by: Cornelia Huck --- hw/s390x/css-bridge.c | 26 +++++++++++++++++++++++++- hw/s390x/s390-virtio-ccw.c | 4 ++++ include/hw/s390x/css-bridge.h | 7 +++++++ 3 files changed, 36 insertions(+), 1 deletion(-) diff --git a/hw/s390x/css-bridge.c b/hw/s390x/css-bridge.c index e4c24e21f3..9a7f7ee60c 100644 --- a/hw/s390x/css-bridge.c +++ b/hw/s390x/css-bridge.c @@ -59,11 +59,28 @@ static void virtual_css_bus_reset(BusState *qbus) css_reset(); } +static char *virtual_css_bus_get_dev_path(DeviceState *dev) +{ + CcwDevice *ccw_dev = CCW_DEVICE(dev); + SubchDev *sch = ccw_dev->sch; + VirtualCssBridge *bridge = + VIRTUAL_CSS_BRIDGE(qdev_get_parent_bus(dev)->parent); + + /* + * We can't provide a dev path for backward compatibility on + * older machines, as it is visible in the migration stream. + */ + return bridge->css_dev_path ? + g_strdup_printf("/%02x.%1x.%04x", sch->cssid, sch->ssid, sch->devno) : + NULL; +} + static void virtual_css_bus_class_init(ObjectClass *klass, void *data) { BusClass *k = BUS_CLASS(klass); k->reset = virtual_css_bus_reset; + k->get_dev_path = virtual_css_bus_get_dev_path; } static const TypeInfo virtual_css_bus_info = { @@ -95,6 +112,12 @@ VirtualCssBus *virtual_css_bus_init(void) /***************** Virtual-css Bus Bridge Device ********************/ +static Property virtual_css_bridge_properties[] = { + DEFINE_PROP_BOOL("css_dev_path", VirtualCssBridge, css_dev_path, + true), + DEFINE_PROP_END_OF_LIST(), +}; + static void virtual_css_bridge_class_init(ObjectClass *klass, void *data) { HotplugHandlerClass *hc = HOTPLUG_HANDLER_CLASS(klass); @@ -102,12 +125,13 @@ static void virtual_css_bridge_class_init(ObjectClass *klass, void *data) hc->unplug = ccw_device_unplug; set_bit(DEVICE_CATEGORY_BRIDGE, dc->categories); + dc->props = virtual_css_bridge_properties; } static const TypeInfo virtual_css_bridge_info = { .name = TYPE_VIRTUAL_CSS_BRIDGE, .parent = TYPE_SYS_BUS_DEVICE, - .instance_size = sizeof(SysBusDevice), + .instance_size = sizeof(VirtualCssBridge), .class_init = virtual_css_bridge_class_init, .interfaces = (InterfaceInfo[]) { { TYPE_HOTPLUG_HANDLER }, diff --git a/hw/s390x/s390-virtio-ccw.c b/hw/s390x/s390-virtio-ccw.c index caf0a682a7..91d9cefbb5 100644 --- a/hw/s390x/s390-virtio-ccw.c +++ b/hw/s390x/s390-virtio-ccw.c @@ -322,6 +322,10 @@ static const TypeInfo ccw_machine_info = { .driver = TYPE_S390_IPL,\ .property = "iplbext_migration",\ .value = "off",\ + }, {\ + .driver = TYPE_VIRTUAL_CSS_BRIDGE,\ + .property = "css_dev_path",\ + .value = "off",\ }, #define CCW_COMPAT_2_5 \ diff --git a/include/hw/s390x/css-bridge.h b/include/hw/s390x/css-bridge.h index ad73c1faf6..5a0203be5f 100644 --- a/include/hw/s390x/css-bridge.h +++ b/include/hw/s390x/css-bridge.h @@ -16,7 +16,14 @@ #include "hw/qdev-core.h" /* virtual css bridge */ +typedef struct VirtualCssBridge { + SysBusDevice sysbus_dev; + bool css_dev_path; +} VirtualCssBridge; + #define TYPE_VIRTUAL_CSS_BRIDGE "virtual-css-bridge" +#define VIRTUAL_CSS_BRIDGE(obj) \ + OBJECT_CHECK(VirtualCssBridge, (obj), TYPE_VIRTUAL_CSS_BRIDGE) /* virtual css bus type */ typedef struct VirtualCssBus {