[Qemu-devel] [PATCH v3 1/2] pvpanic: initialization cleanup

[Michael S. Tsirkin]

Avoid use of static variables: PC systems
initialize pvpanic device through pvpanic_init,
so we can simply create the fw_cfg file at that point.
This also makes it possible to skip device
creation completely if fw_cfg is not there, e.g. for xen -
so the ports it reserves are not discoverable by guests.

Also, make pvpanic_init void since callers ignore return
status anyway.

Cc: Stefano Stabellini <address@hidden>
Cc: Laszlo Ersek <address@hidden>
Cc: Paul Durrant <address@hidden>
Signed-off-by: Michael S. Tsirkin <address@hidden>
---
Chanes from v2:
    skip device creation completely if !fw_cfg
    make pvpanic_init void
Changes from v1:
    don't assert if !fw_cfg


 hw/misc/pvpanic.c    | 30 ++++++++++++++++--------------
 include/hw/i386/pc.h |  2 +-
 2 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/hw/misc/pvpanic.c b/hw/misc/pvpanic.c
index 060099b..83ed226 100644
--- a/hw/misc/pvpanic.c
+++ b/hw/misc/pvpanic.c
@@ -97,26 +97,28 @@ static void pvpanic_isa_realizefn(DeviceState *dev, Error 
**errp)
 {
     ISADevice *d = ISA_DEVICE(dev);
     PVPanicState *s = ISA_PVPANIC_DEVICE(dev);
-    static bool port_configured;
-    FWCfgState *fw_cfg;
 
     isa_register_ioport(d, &s->io, s->ioport);
+}
 
-    if (!port_configured) {
-        fw_cfg = fw_cfg_find();
-        if (fw_cfg) {
-            fw_cfg_add_file(fw_cfg, "etc/pvpanic-port",
-                            g_memdup(&s->ioport, sizeof(s->ioport)),
-                            sizeof(s->ioport));
-            port_configured = true;
-        }
-    }
+static void pvpanic_fw_cfg(ISADevice *dev, FWCfgState *fw_cfg)
+{
+    PVPanicState *s = ISA_PVPANIC_DEVICE(dev);
+
+    fw_cfg_add_file(fw_cfg, "etc/pvpanic-port",
+                    g_memdup(&s->ioport, sizeof(s->ioport)),
+                    sizeof(s->ioport));
 }
 
-int pvpanic_init(ISABus *bus)
+void pvpanic_init(ISABus *bus)
 {
-    isa_create_simple(bus, TYPE_ISA_PVPANIC_DEVICE);
-    return 0;
+    ISADevice *dev;
+    FWCfgState *fw_cfg = fw_cfg_find();
+    if (!fw_cfg) {
+        return;
+    }
+    dev = isa_create_simple (bus, TYPE_ISA_PVPANIC_DEVICE);
+    pvpanic_fw_cfg(dev, fw_cfg);
 }
 
 static Property pvpanic_isa_properties[] = {
diff --git a/include/hw/i386/pc.h b/include/hw/i386/pc.h
index ba9ba1a..458eded 100644
--- a/include/hw/i386/pc.h
+++ b/include/hw/i386/pc.h
@@ -196,7 +196,7 @@ static inline bool isa_ne2000_init(ISABus *bus, int base, 
int irq, NICInfo *nd)
 void pc_system_firmware_init(MemoryRegion *rom_memory);
 
 /* pvpanic.c */
-int pvpanic_init(ISABus *bus);
+void pvpanic_init(ISABus *bus);
 
 /* e820 types */
 #define E820_RAM        1
-- 
MST