introduce a new qom device to deal with panicked event

pvpanic device is used to send guest panic event from guest to qemu.

When guest panic happens, pvpanic device driver will write a event
number to IO port 0x505(which is the IO port occupied by pvpanic device,
by default). On receiving the event, pvpanic device will pause guest
cpu(s), and send a qmp event QEVENT_GUEST_PANICKED.

Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-id: b66077a40235b3531632a05a6ff373850afc7d2e.1366945969.git.hutao@cn.fujitsu.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

default-configs/i386-softmmu.mak

@@ -44,3 +44,4 @@ CONFIG_LPC_ICH9=y
 CONFIG_PCI_Q35=y
 CONFIG_APIC=y
 CONFIG_IOAPIC=y
+CONFIG_PVPANIC=y

default-configs/x86_64-softmmu.mak

@@ -44,3 +44,4 @@ CONFIG_LPC_ICH9=y
 CONFIG_PCI_Q35=y
 CONFIG_APIC=y
 CONFIG_IOAPIC=y
+CONFIG_PVPANIC=y

hw/misc/Makefile.objs

@@ -39,3 +39,5 @@ obj-$(CONFIG_OMAP) += omap_tap.o
 obj-$(CONFIG_PXA2XX) += pxa2xx_pcmcia.o
 obj-$(CONFIG_SLAVIO) += slavio_misc.o
 obj-$(CONFIG_ZYNQ) += zynq_slcr.o
+
+obj-$(CONFIG_PVPANIC) += pvpanic.o

hw/misc/pvpanic.c

@@ -0,0 +1,123 @@
+/*
+ * QEMU simulated pvpanic device.
+ *
+ * Copyright Fujitsu, Corp. 2013
+ *
+ * Authors:
+ *     Wen Congyang <wency@cn.fujitsu.com>
+ *     Hu Tao <hutao@cn.fujitsu.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qapi/qmp/qobject.h"
+#include "qapi/qmp/qjson.h"
+#include "monitor/monitor.h"
+#include "sysemu/sysemu.h"
+#include "qemu/log.h"
+
+/* The bit of supported pv event */
+#define PVPANIC_F_PANICKED      0
+
+/* The pv event value */
+#define PVPANIC_PANICKED        (1 << PVPANIC_F_PANICKED)
+
+#define TYPE_ISA_PVPANIC_DEVICE    "pvpanic"
+#define ISA_PVPANIC_DEVICE(obj)    \
+    OBJECT_CHECK(PVPanicState, (obj), TYPE_ISA_PVPANIC_DEVICE)
+
+static void panicked_mon_event(const char *action)
+{
+    QObject *data;
+
+    data = qobject_from_jsonf("{ 'action': %s }", action);
+    monitor_protocol_event(QEVENT_GUEST_PANICKED, data);
+    qobject_decref(data);
+}
+
+static void handle_event(int event)
+{
+    static bool logged;
+
+    if (event & ~PVPANIC_PANICKED && !logged) {
+        qemu_log_mask(LOG_GUEST_ERROR, "pvpanic: unknown event %#x.\n", event);
+        logged = true;
+    }
+
+    if (event & PVPANIC_PANICKED) {
+        panicked_mon_event("pause");
+        vm_stop(RUN_STATE_GUEST_PANICKED);
+        return;
+    }
+}
+
+#include "hw/isa/isa.h"
+
+typedef struct PVPanicState {
+    ISADevice parent_obj;
+
+    MemoryRegion io;
+    uint16_t ioport;
+} PVPanicState;
+
+/* return supported events on read */
+static uint64_t pvpanic_ioport_read(void *opaque, hwaddr addr, unsigned size)
+{
+    return PVPANIC_PANICKED;
+}
+
+static void pvpanic_ioport_write(void *opaque, hwaddr addr, uint64_t val,
+                                 unsigned size)
+{
+    handle_event(val);
+}
+
+static const MemoryRegionOps pvpanic_ops = {
+    .read = pvpanic_ioport_read,
+    .write = pvpanic_ioport_write,
+    .impl = {
+        .min_access_size = 1,
+        .max_access_size = 1,
+    },
+};
+
+static int pvpanic_isa_initfn(ISADevice *dev)
+{
+    PVPanicState *s = ISA_PVPANIC_DEVICE(dev);
+
+    memory_region_init_io(&s->io, &pvpanic_ops, s, "pvpanic", 1);
+    isa_register_ioport(dev, &s->io, s->ioport);
+
+    return 0;
+}
+
+static Property pvpanic_isa_properties[] = {
+    DEFINE_PROP_UINT16("ioport", PVPanicState, ioport, 0x505),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void pvpanic_isa_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    ISADeviceClass *ic = ISA_DEVICE_CLASS(klass);
+
+    ic->init = pvpanic_isa_initfn;
+    dc->no_user = 1;
+    dc->props = pvpanic_isa_properties;
+}
+
+static TypeInfo pvpanic_isa_info = {
+    .name          = TYPE_ISA_PVPANIC_DEVICE,
+    .parent        = TYPE_ISA_DEVICE,
+    .instance_size = sizeof(PVPanicState),
+    .class_init    = pvpanic_isa_class_init,
+};
+
+static void pvpanic_register_types(void)
+{
+    type_register_static(&pvpanic_isa_info);
+}
+
+type_init(pvpanic_register_types)