[fix] area_binding should create the binding

As we cannot find out in advance the binding an area uses, it is not
possible to use a correctly allocated pointer to aml_area_binding.

Fixes a segfault we observed outside of current unit-tests.

src/aml.h

@@ -104,7 +104,7 @@ struct aml_area_ops {
 	void (*release)(struct aml_area_data *, void *);
 	void *(*mmap)(struct aml_area_data *, void *ptr, size_t);
 	int (*available)(struct aml_area_data *);
-	int (*binding)(struct aml_area_data *, struct aml_binding *);
+	int (*binding)(struct aml_area_data *, struct aml_binding **);
 };
 
 struct aml_area {
@@ -182,7 +182,7 @@ struct aml_area_linux_mbind_ops {
 int aml_area_linux_mbind_setdata(struct aml_area_linux_mbind_data *, int,
 				 unsigned long *);
 int aml_area_linux_mbind_generic_binding(struct aml_area_linux_mbind_data *,
-					 struct aml_binding *);
+					 struct aml_binding **);
 int aml_area_linux_mbind_regular_pre_bind(struct aml_area_linux_mbind_data *);
 int aml_area_linux_mbind_regular_post_bind(struct aml_area_linux_mbind_data *,
 					   void *, size_t);
@@ -275,7 +275,7 @@ void *aml_area_acquire(struct aml_area *, size_t);
 void aml_area_release(struct aml_area *, void *);
 void *aml_area_mmap(struct aml_area *, void *, size_t);
 int aml_area_available(struct aml_area *);
-int aml_area_binding(struct aml_area *, struct aml_binding *);
+int aml_area_binding(struct aml_area *, struct aml_binding **);
 
 /*******************************************************************************
  * DMA Engines:

src/area.c

@@ -55,7 +55,7 @@ int aml_area_available(struct aml_area *area)
 	return area->ops->available(area->data);
 }
 
-int aml_area_binding(struct aml_area *area, struct aml_binding *binding)
+int aml_area_binding(struct aml_area *area, struct aml_binding **binding)
 {
 	assert(area != NULL);
 	return area->ops->binding(area->data, binding);

src/area_linux.c

@@ -28,7 +28,7 @@ int aml_area_linux_available(struct aml_area_data *a)
 	return 1;
 }
 
-int aml_area_linux_binding(struct aml_area_data *a, struct aml_binding *b)
+int aml_area_linux_binding(struct aml_area_data *a, struct aml_binding **b)
 {
 	assert(a != NULL);
 	struct aml_area_linux *area = (struct aml_area_linux *)a;

src/area_linux_mbind.c

@@ -10,7 +10,7 @@
 
 /* common to both methods */
 int aml_area_linux_mbind_generic_binding(struct aml_area_linux_mbind_data *data,
-					 struct aml_binding *b)
+					 struct aml_binding **b)
 {
 	assert(data != NULL);
 	/* not exactly proper, we should inspect the nodemask to find the real
@@ -20,12 +20,12 @@ int aml_area_linux_mbind_generic_binding(struct aml_area_linux_mbind_data *data,
 	{
 		for(int i = 0; i < AML_MAX_NUMA_NODES; i++)
 			if(AML_NODEMASK_ISSET(data->nodemask, i))
-				return aml_binding_init(b, AML_BINDING_TYPE_SINGLE,i);
+				return aml_binding_create(b, AML_BINDING_TYPE_SINGLE,i);
 	}
 	else if(data->policy == MPOL_INTERLEAVE)
 	{
-		return aml_binding_init(b, AML_BINDING_TYPE_INTERLEAVE,
-					data->nodemask);
+		return aml_binding_create(b, AML_BINDING_TYPE_INTERLEAVE,
+					  data->nodemask);
 	}
 	return 0;
 }

src/area_posix.c

@@ -26,11 +26,11 @@ int aml_area_posix_available(struct aml_area_data *data)
 /* same thing here, it makes no sense to ask for this area to provide its
  * binding scheme, as no-one should migrate to this area.
  */
-int aml_area_posix_binding(struct aml_area_data *data, struct aml_binding *b)
+int aml_area_posix_binding(struct aml_area_data *data, struct aml_binding **b)
 {
 	assert(data != NULL);
 	/* numa node 0 should always be available */
-	return aml_binding_init(b, AML_BINDING_TYPE_SINGLE, 0);
+	return aml_binding_create(b, AML_BINDING_TYPE_SINGLE, 0);
 }
 
 /*******************************************************************************