[PATCH v2 1/1] hw/s390x: modularize virtio-gpu-ccw

[Halil Pasic <pasic@linux.ibm.com>]

Since the virtio-gpu-ccw device depends on the hw-display-virtio-gpu
module, which provides the type virtio-gpu-device, packaging the
hw-display-virtio-gpu module as a separate package that may or may not
be installed along with the qemu package leads to problems. Namely if
the hw-display-virtio-gpu is absent, qemu continues to advertise
virtio-gpu-ccw, but it aborts not only when one attempts using
virtio-gpu-ccw, but also when libvirtd's capability probing tries
to instantiate the type to introspect it.

Let us thus introduce a module named hw-s390x-virtio-gpu-ccw that
is going to provide the virtio-gpu-ccw device. The hw-s390x prefix
was chosen because it is not a portable device.

With virtio-gpu-ccw built as a module, the correct way to package a
modularized qemu is to require that hw-display-virtio-gpu must be
installed whenever the module hw-s390x-virtio-gpu-ccw.

The definition S390_ADAPTER_SUPPRESSIBLE was moved to "cpu.h", per
suggestion of Thomas Huth. From interface design perspective, IMHO, not
a good thing as it belongs to the public interface of
css_register_io_adapters(). We did this because CONFIG_KVM requeires
NEED_CPU_H and Thomas, and other commenters did not like the
consequences of that.

Moving the interrupt related declarations to s390_flic.h was suggested
by Cornelia Huck.

Introducing type_register_mayfail() was suggested by Gerd Hoffmann.

Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
---
 hw/s390x/meson.build         |  7 +++++-
 hw/s390x/virtio-ccw-gpu.c    |  4 ++++
 include/hw/s390x/css.h       |  7 ------
 include/hw/s390x/s390_flic.h |  3 +++
 include/qom/object.h         | 22 +++++++++++++++++++
 qom/object.c                 | 42 ++++++++++++++++++++++++------------
 target/s390x/cpu.h           |  9 +++++---
 util/module.c                |  1 +
 8 files changed, 70 insertions(+), 25 deletions(-)

diff --git a/hw/s390x/meson.build b/hw/s390x/meson.build
index 2a7818d94b..7ac972afcf 100644
--- a/hw/s390x/meson.build
+++ b/hw/s390x/meson.build
@@ -34,7 +34,6 @@ virtio_ss.add(files('virtio-ccw.c'))
 virtio_ss.add(when: 'CONFIG_VIRTIO_BALLOON', if_true: files('virtio-ccw-balloon.c'))
 virtio_ss.add(when: 'CONFIG_VIRTIO_BLK', if_true: files('virtio-ccw-blk.c'))
 virtio_ss.add(when: 'CONFIG_VIRTIO_CRYPTO', if_true: files('virtio-ccw-crypto.c'))
-virtio_ss.add(when: 'CONFIG_VIRTIO_GPU', if_true: files('virtio-ccw-gpu.c'))
 virtio_ss.add(when: 'CONFIG_VIRTIO_INPUT', if_true: files('virtio-ccw-input.c'))
 virtio_ss.add(when: 'CONFIG_VIRTIO_NET', if_true: files('virtio-ccw-net.c'))
 virtio_ss.add(when: 'CONFIG_VIRTIO_RNG', if_true: files('virtio-ccw-rng.c'))
@@ -46,3 +45,9 @@ virtio_ss.add(when: 'CONFIG_VHOST_USER_FS', if_true: files('vhost-user-fs-ccw.c'
 s390x_ss.add_all(when: 'CONFIG_VIRTIO_CCW', if_true: virtio_ss)
 
 hw_arch += {'s390x': s390x_ss}
+
+hw_s390x_modules = {}
+virtio_gpu_ccw_ss = ss.source_set()
+virtio_gpu_ccw_ss.add(when: 'CONFIG_VIRTIO_GPU', if_true: [files('virtio-ccw-gpu.c'), pixman])
+hw_s390x_modules += {'virtio-gpu-ccw': virtio_gpu_ccw_ss}
+modules += {'hw-s390x': hw_s390x_modules}
diff --git a/hw/s390x/virtio-ccw-gpu.c b/hw/s390x/virtio-ccw-gpu.c
index c301e2586b..5ac9b6b2a6 100644
--- a/hw/s390x/virtio-ccw-gpu.c
+++ b/hw/s390x/virtio-ccw-gpu.c
@@ -62,7 +62,11 @@ static const TypeInfo virtio_ccw_gpu = {
 
 static void virtio_ccw_gpu_register(void)
 {
+#ifdef CONFIG_MODULES
+    type_register_static_mayfail(&virtio_ccw_gpu);
+#else
     type_register_static(&virtio_ccw_gpu);
+#endif
 }
 
 type_init(virtio_ccw_gpu_register)
diff --git a/include/hw/s390x/css.h b/include/hw/s390x/css.h
index 08c869ab0a..7858666307 100644
--- a/include/hw/s390x/css.h
+++ b/include/hw/s390x/css.h
@@ -12,7 +12,6 @@
 #ifndef CSS_H
 #define CSS_H
 
-#include "cpu.h"
 #include "hw/s390x/adapter.h"
 #include "hw/s390x/s390_flic.h"
 #include "hw/s390x/ioinst.h"
@@ -233,12 +232,6 @@ uint32_t css_get_adapter_id(CssIoAdapterType type, uint8_t isc);
 void css_register_io_adapters(CssIoAdapterType type, bool swap, bool maskable,
                               uint8_t flags, Error **errp);
 
-#ifndef CONFIG_KVM
-#define S390_ADAPTER_SUPPRESSIBLE 0x01
-#else
-#define S390_ADAPTER_SUPPRESSIBLE KVM_S390_ADAPTER_SUPPRESSIBLE
-#endif
-
 #ifndef CONFIG_USER_ONLY
 SubchDev *css_find_subch(uint8_t m, uint8_t cssid, uint8_t ssid,
                          uint16_t schid);
diff --git a/include/hw/s390x/s390_flic.h b/include/hw/s390x/s390_flic.h
index e91b15d2d6..3907a13d07 100644
--- a/include/hw/s390x/s390_flic.h
+++ b/include/hw/s390x/s390_flic.h
@@ -134,6 +134,9 @@ void s390_flic_init(void);
 S390FLICState *s390_get_flic(void);
 QEMUS390FLICState *s390_get_qemu_flic(S390FLICState *fs);
 S390FLICStateClass *s390_get_flic_class(S390FLICState *fs);
+void s390_crw_mchk(void);
+void s390_io_interrupt(uint16_t subchannel_id, uint16_t subchannel_nr,
+                       uint32_t io_int_parm, uint32_t io_int_word);
 bool ais_needed(void *opaque);
 
 #endif /* HW_S390_FLIC_H */
diff --git a/include/qom/object.h b/include/qom/object.h
index 6721cd312e..3428546d91 100644
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -826,6 +826,17 @@ const char *object_get_typename(const Object *obj);
  */
 Type type_register_static(const TypeInfo *info);
 
+/**
+ * type_register_static_mayfail:
+ * @info: The #TypeInfo of the new type.
+ *
+ * @info and all of the strings it points to should exist for the life time
+ * that the type is registered.
+ *
+ * Returns: the new #Type or NULL if missing a parent type.
+ */
+Type type_register_static_mayfail(const TypeInfo *info);
+
 /**
  * type_register:
  * @info: The #TypeInfo of the new type
@@ -837,6 +848,17 @@ Type type_register_static(const TypeInfo *info);
  */
 Type type_register(const TypeInfo *info);
 
+/**
+ * type_register_mayfail:
+ * @info: The #TypeInfo of the new type
+ *
+ * Unlike type_register_static(), this call does not require @info or its
+ * string members to continue to exist after the call returns.
+ *
+ * Returns: the new #Type or NULL if missing a parent type.
+ */
+Type type_register_mayfail(const TypeInfo *info);
+
 /**
  * type_register_static_array:
  * @infos: The array of the new type #TypeInfo structures.
diff --git a/qom/object.c b/qom/object.c
index 491823db4a..ed217cbfb0 100644
--- a/qom/object.c
+++ b/qom/object.c
@@ -135,7 +135,7 @@ static TypeImpl *type_new(const TypeInfo *info)
     return ti;
 }
 
-static TypeImpl *type_register_internal(const TypeInfo *info)
+static TypeImpl *type_register_internal(const TypeInfo *info, bool mayfail)
 {
     TypeImpl *ti;
     ti = type_new(info);
@@ -147,7 +147,13 @@ static TypeImpl *type_register_internal(const TypeInfo *info)
 TypeImpl *type_register(const TypeInfo *info)
 {
     assert(info->parent);
-    return type_register_internal(info);
+    return type_register_internal(info, false);
+}
+
+TypeImpl *type_register_mayfail(const TypeInfo *info)
+{
+    assert(info->parent);
+    return type_register_internal(info, true);
 }
 
 TypeImpl *type_register_static(const TypeInfo *info)
@@ -155,6 +161,11 @@ TypeImpl *type_register_static(const TypeInfo *info)
     return type_register(info);
 }
 
+TypeImpl *type_register_static_mayfail(const TypeInfo *info)
+{
+    return type_register_mayfail(info);
+}
+
 void type_register_static_array(const TypeInfo *infos, int nr_infos)
 {
     int i;
@@ -173,13 +184,16 @@ static TypeImpl *type_get_by_name(const char *name)
     return type_table_lookup(name);
 }
 
-static TypeImpl *type_get_parent(TypeImpl *type)
+static TypeImpl *type_get_parent(TypeImpl *type, bool mayfail)
 {
     if (!type->parent_type && type->parent) {
         type->parent_type = type_get_by_name(type->parent);
         if (!type->parent_type) {
             fprintf(stderr, "Type '%s' is missing its parent '%s'\n",
                     type->name, type->parent);
+            if (mayfail) {
+                return NULL;
+            }
             abort();
         }
     }
@@ -199,7 +213,7 @@ static size_t type_class_get_size(TypeImpl *ti)
     }
 
     if (type_has_parent(ti)) {
-        return type_class_get_size(type_get_parent(ti));
+        return type_class_get_size(type_get_parent(ti, false));
     }
 
     return sizeof(ObjectClass);
@@ -212,7 +226,7 @@ static size_t type_object_get_size(TypeImpl *ti)
     }
 
     if (type_has_parent(ti)) {
-        return type_object_get_size(type_get_parent(ti));
+        return type_object_get_size(type_get_parent(ti, false));
     }
 
     return 0;
@@ -236,7 +250,7 @@ static bool type_is_ancestor(TypeImpl *type, TypeImpl *target_type)
             return true;
         }
 
-        type = type_get_parent(type);
+        type = type_get_parent(type, false);
     }
 
     return false;
@@ -307,7 +321,7 @@ static void type_initialize(TypeImpl *ti)
     }
     ti->class = g_malloc0(ti->class_size);
 
-    parent = type_get_parent(ti);
+    parent = type_get_parent(ti, false);
     if (parent) {
         type_initialize(parent);
         GSList *e;
@@ -357,7 +371,7 @@ static void type_initialize(TypeImpl *ti)
         if (parent->class_base_init) {
             parent->class_base_init(ti->class, ti->class_data);
         }
-        parent = type_get_parent(parent);
+        parent = type_get_parent(parent, false);
     }
 
     if (ti->class_init) {
@@ -368,7 +382,7 @@ static void type_initialize(TypeImpl *ti)
 static void object_init_with_type(Object *obj, TypeImpl *ti)
 {
     if (type_has_parent(ti)) {
-        object_init_with_type(obj, type_get_parent(ti));
+        object_init_with_type(obj, type_get_parent(ti, false));
     }
 
     if (ti->instance_init) {
@@ -383,7 +397,7 @@ static void object_post_init_with_type(Object *obj, TypeImpl *ti)
     }
 
     if (type_has_parent(ti)) {
-        object_post_init_with_type(obj, type_get_parent(ti));
+        object_post_init_with_type(obj, type_get_parent(ti, false));
     }
 }
 
@@ -674,7 +688,7 @@ static void object_deinit(Object *obj, TypeImpl *type)
     }
 
     if (type_has_parent(type)) {
-        object_deinit(obj, type_get_parent(type));
+        object_deinit(obj, type_get_parent(type, false));
     }
 }
 
@@ -1040,7 +1054,7 @@ ObjectClass *module_object_class_by_name(const char *typename)
 
 ObjectClass *object_class_get_parent(ObjectClass *class)
 {
-    TypeImpl *type = type_get_parent(class->type);
+    TypeImpl *type = type_get_parent(class->type, false);
 
     if (!type) {
         return NULL;
@@ -2791,8 +2805,8 @@ static void register_types(void)
         .abstract = true,
     };
 
-    type_interface = type_register_internal(&interface_info);
-    type_register_internal(&object_info);
+    type_interface = type_register_internal(&interface_info, false);
+    type_register_internal(&object_info, false);
 }
 
 type_init(register_types)
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 60d434d5ed..b434b905c0 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -40,6 +40,12 @@
 
 #define S390_MAX_CPUS 248
 
+#ifndef CONFIG_KVM
+#define S390_ADAPTER_SUPPRESSIBLE 0x01
+#else
+#define S390_ADAPTER_SUPPRESSIBLE KVM_S390_ADAPTER_SUPPRESSIBLE
+#endif
+
 typedef struct PSW {
     uint64_t mask;
     uint64_t addr;
@@ -806,9 +812,6 @@ int cpu_s390x_signal_handler(int host_signum, void *pinfo, void *puc);
 
 
 /* interrupt.c */
-void s390_crw_mchk(void);
-void s390_io_interrupt(uint16_t subchannel_id, uint16_t subchannel_nr,
-                       uint32_t io_int_parm, uint32_t io_int_word);
 #define RA_IGNORED                  0
 void s390_program_interrupt(CPUS390XState *env, uint32_t code, uintptr_t ra);
 /* service interrupts are floating therefore we must not pass an cpustate */
diff --git a/util/module.c b/util/module.c
index c65060c167..cbe89fede6 100644
--- a/util/module.c
+++ b/util/module.c
@@ -304,6 +304,7 @@ static struct {
     { "virtio-gpu-pci-base",   "hw-", "display-virtio-gpu-pci" },
     { "virtio-gpu-pci",        "hw-", "display-virtio-gpu-pci" },
     { "vhost-user-gpu-pci",    "hw-", "display-virtio-gpu-pci" },
+    { "virtio-gpu-ccw",        "hw-", "s390x-virtio-gpu-ccw"   },
     { "virtio-vga-base",       "hw-", "display-virtio-vga"    },
     { "virtio-vga",            "hw-", "display-virtio-vga"    },
     { "vhost-user-vga",        "hw-", "display-virtio-vga"    },

base-commit: 1af5629673bb5c1592d993f9fb6119a62845f576
-- 
2.25.1