qom: enforce readonly nature of link's check callback

link's check callback is supposed to verify/permit setting it,
however currently nothing restricts it from misusing it
and modifying target object from within.
Make sure that readonly semantics are checked by compiler
to prevent callback's misuse.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170714021509.23681-2-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/hw/core/qdev-properties.c b/hw/core/qdev-properties.c
index f11d57831bcf7bb8931a82e56436f27f6599711e..113ce7df46b17a6a3bd2b1d4381728ff1d2ecbfe 100644 (file)
--- a/hw/core/qdev-properties.c
+++ b/hw/core/qdev-properties.c
@@ -25,7 +25,8 @@ void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
     }
 }
 
-void qdev_prop_allow_set_link_before_realize(Object *obj, const char *name,
+void qdev_prop_allow_set_link_before_realize(const Object *obj,
+                                             const char *name,
                                              Object *val, Error **errp)
 {
     DeviceState *dev = DEVICE(obj);

diff --git a/hw/display/xlnx_dp.c b/hw/display/xlnx_dp.c
index a77d7db22f098f1847f2abf7e30f6e19a5521f53..561f828e7ad47f3abeacd889a34c57e4b16e4144 100644 (file)
--- a/hw/display/xlnx_dp.c
+++ b/hw/display/xlnx_dp.c
@@ -515,7 +515,7 @@ static void xlnx_dp_aux_set_command(XlnxDPState *s, uint32_t value)
     s->core_registers[DP_INTERRUPT_SIGNAL_STATE] |= 0x04;
 }
 
-static void xlnx_dp_set_dpdma(Object *obj, const char *name, Object *val,
+static void xlnx_dp_set_dpdma(const Object *obj, const char *name, Object *val,
                               Error **errp)
 {
     XlnxDPState *s = XLNX_DP(obj);

diff --git a/hw/ipmi/ipmi.c b/hw/ipmi/ipmi.c
index afafe1400f0e38529f9419abcc8599fccaeb0df7..b27babd5047c71afba02485102c7bc5667ff3b3c 100644 (file)
--- a/hw/ipmi/ipmi.c
+++ b/hw/ipmi/ipmi.c
@@ -90,7 +90,7 @@ static TypeInfo ipmi_interface_type_info = {
     .class_init = ipmi_interface_class_init,
 };
 
-static void isa_ipmi_bmc_check(Object *obj, const char *name,
+static void isa_ipmi_bmc_check(const Object *obj, const char *name,
                                Object *val, Error **errp)
 {
     IPMIBmc *bmc = IPMI_BMC(val);

diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
index b72258e28fc5da0ec3725842ab0d1a093bdc6f10..5e2349547304250a4244392cb84791acc2198db3 100644 (file)
--- a/hw/mem/pc-dimm.c
+++ b/hw/mem/pc-dimm.c
@@ -367,7 +367,7 @@ static void pc_dimm_get_size(Object *obj, Visitor *v, const char *name,
     visit_type_uint64(v, name, &value, errp);
 }
 
-static void pc_dimm_check_memdev_is_busy(Object *obj, const char *name,
+static void pc_dimm_check_memdev_is_busy(const Object *obj, const char *name,
                                       Object *val, Error **errp)
 {
     Error *local_err = NULL;

diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 7f678d01970300bdf121690ff3c1b78c87f0c554..731f3c1d4ffacbba2532cd0347bda4ddb4fda24c 100644 (file)
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -1009,7 +1009,7 @@ static const TypeInfo ivshmem_common_info = {
     .class_init    = ivshmem_common_class_init,
 };
 
-static void ivshmem_check_memdev_is_busy(Object *obj, const char *name,
+static void ivshmem_check_memdev_is_busy(const Object *obj, const char *name,
                                          Object *val, Error **errp)
 {
     if (host_memory_backend_is_mapped(MEMORY_BACKEND(val))) {

diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
index 0353eb6d5dcfee544ae399b4612e53d360de7df4..25908930164ba64c4472743d2f0f0ab6586ecf4c 100644 (file)
--- a/hw/virtio/virtio-crypto.c
+++ b/hw/virtio/virtio-crypto.c
@@ -889,7 +889,7 @@ static void virtio_crypto_class_init(ObjectClass *klass, void *data)
 }
 
 static void
-virtio_crypto_check_cryptodev_is_used(Object *obj, const char *name,
+virtio_crypto_check_cryptodev_is_used(const Object *obj, const char *name,
                                       Object *val, Error **errp)
 {
     if (cryptodev_backend_is_used(CRYPTODEV_BACKEND(val))) {

diff --git a/include/hw/qdev-properties.h b/include/hw/qdev-properties.h
index 0604c337e06a4d3d57c82c2b1195d872fe5d042b..9edded29d29f4fa1f2f0d437b0af4fe581a25064 100644 (file)
--- a/include/hw/qdev-properties.h
+++ b/include/hw/qdev-properties.h
@@ -272,7 +272,8 @@ void qdev_prop_set_after_realize(DeviceState *dev, const char *name,
  * This function should be used as the check() argument to
  * object_property_add_link().
  */
-void qdev_prop_allow_set_link_before_realize(Object *obj, const char *name,
+void qdev_prop_allow_set_link_before_realize(const Object *obj,
+                                             const char *name,
                                              Object *val, Error **errp);
 
 #endif

diff --git a/include/qom/object.h b/include/qom/object.h
index abaeb8cf4ec20181b201756216a644a58b43087c..1b828994fa3a89a2f58a891aac8e20c779f0ab57 100644 (file)
--- a/include/qom/object.h
+++ b/include/qom/object.h
@@ -764,7 +764,7 @@ ObjectClass *object_get_class(Object *obj);
  *
  * Returns: The QOM typename of @obj.
  */
-const char *object_get_typename(Object *obj);
+const char *object_get_typename(const Object *obj);
 
 /**
  * type_register_static:
@@ -1319,7 +1319,7 @@ typedef enum {
  * callback function.  It allows the link property to be set and never returns
  * an error.
  */
-void object_property_allow_set_link(Object *, const char *,
+void object_property_allow_set_link(const Object *, const char *,
                                     Object *, Error **);
 
 /**
@@ -1352,7 +1352,7 @@ void object_property_allow_set_link(Object *, const char *,
  */
 void object_property_add_link(Object *obj, const char *name,
                               const char *type, Object **child,
-                              void (*check)(Object *obj, const char *name,
+                              void (*check)(const Object *obj, const char *name,
                                             Object *val, Error **errp),
                               ObjectPropertyLinkFlags flags,
                               Error **errp);

diff --git a/qom/object.c b/qom/object.c
index 5f6fdfa6e62343fead731d0935cc6291f1ca1e4e..dfdbd50f042c2f8a5311c0ca844f49abaa76738e 100644 (file)
--- a/qom/object.c
+++ b/qom/object.c
@@ -740,7 +740,7 @@ out:
     return ret;
 }
 
-const char *object_get_typename(Object *obj)
+const char *object_get_typename(const Object *obj)
 {
     return obj->class->type->name;
 }
@@ -1428,7 +1428,7 @@ out:
     g_free(type);
 }
 
-void object_property_allow_set_link(Object *obj, const char *name,
+void object_property_allow_set_link(const Object *obj, const char *name,
                                     Object *val, Error **errp)
 {
     /* Allow the link to be set, always */
@@ -1436,7 +1436,7 @@ void object_property_allow_set_link(Object *obj, const char *name,
 
 typedef struct {
     Object **child;
-    void (*check)(Object *, const char *, Object *, Error **);
+    void (*check)(const Object *, const char *, Object *, Error **);
     ObjectPropertyLinkFlags flags;
 } LinkProperty;
 
@@ -1552,7 +1552,7 @@ static void object_release_link_property(Object *obj, const char *name,
 
 void object_property_add_link(Object *obj, const char *name,
                               const char *type, Object **child,
-                              void (*check)(Object *, const char *,
+                              void (*check)(const Object *, const char *,
                                             Object *, Error **),
                               ObjectPropertyLinkFlags flags,
                               Error **errp)