RDMA/uverbs: Use a linear list to describe the compiled-in uapi

The 'tree' data structure is very hard to build at compile time, and this
makes it very limited. The new radix tree based compiler can handle a more
complex input language that does not require the compiler to perfectly
group everything into a neat tree structure.

Instead use a simple list to describe to input, where the list elements
can be of various different 'opcodes' instructing the radix compiler what
to do. Start out with opcodes chaining to other definition lists and
chaining to the existing 'tree' definition.

Replace the very top level of the 'object tree' with this list type and
get rid of struct uverbs_object_tree_def and DECLARE_UVERBS_OBJECT_TREE.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>

4 files changed, 38 insertions, 37 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index 86313e1e9210..1af7bf34c04c 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -2600,7 +2600,7 @@ struct ib_device {
 	const struct cpumask *(*get_vector_affinity)(struct ib_device *ibdev,
 						     int comp_vector);
 
-	const struct uverbs_object_tree_def *const *driver_specs;
+	const struct uapi_definition   *driver_def;
 	enum rdma_driver_id		driver_id;
 };
 
diff --git a/include/rdma/uverbs_ioctl.h b/include/rdma/uverbs_ioctl.h
index 84d3d15f1f38..9fa0cca45783 100644
--- a/include/rdma/uverbs_ioctl.h
+++ b/include/rdma/uverbs_ioctl.h
@@ -296,11 +296,43 @@ struct uverbs_object_def {
 	const struct uverbs_method_def * const (*methods)[];
 };
 
-struct uverbs_object_tree_def {
-	size_t					 num_objects;
-	const struct uverbs_object_def * const (*objects)[];
+enum uapi_definition_kind {
+	UAPI_DEF_END = 0,
+	UAPI_DEF_CHAIN_OBJ_TREE,
+	UAPI_DEF_CHAIN,
 };
 
+struct uapi_definition {
+	u8 kind;
+	union {
+		struct {
+			u16 object_id;
+		} object_start;
+	};
+
+	union {
+		const struct uapi_definition *chain;
+		const struct uverbs_object_def *chain_obj_tree;
+	};
+};
+
+/* Include another struct uapi_definition in this one */
+#define UAPI_DEF_CHAIN(_def_var)                                               \
+	{                                                                      \
+		.kind = UAPI_DEF_CHAIN, .chain = _def_var,                     \
+	}
+
+/* Temporary until the tree base description is replaced */
+#define UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, _object_ptr)                     \
+	{                                                                      \
+		.kind = UAPI_DEF_CHAIN_OBJ_TREE,                               \
+		.object_start = { .object_id = _object_enum },                 \
+		.chain_obj_tree = _object_ptr,                                 \
+	}
+#define UAPI_DEF_CHAIN_OBJ_TREE_NAMED(_object_enum, ...)                       \
+	UAPI_DEF_CHAIN_OBJ_TREE(_object_enum, &UVERBS_OBJECT(_object_enum)),   \
+		##__VA_ARGS__
+
 /*
  * =======================================
  *	Attribute Specifications
@@ -438,21 +470,6 @@ struct uverbs_object_tree_def {
 			    UVERBS_ATTR_MIN_SIZE(0),			       \
 			    UA_OPTIONAL)
 
-/*
- * =======================================
- *	Declaration helpers
- * =======================================
- */
-
-#define DECLARE_UVERBS_OBJECT_TREE(_name, ...)                                 \
-	static const struct uverbs_object_def *const _name##_ptr[] = {         \
-		__VA_ARGS__,                                                   \
-	};                                                                     \
-	static const struct uverbs_object_tree_def _name = {                   \
-		.num_objects = ARRAY_SIZE(_name##_ptr),                        \
-		.objects = &_name##_ptr,                                       \
-	}
-
 /* =================================================
  *              Parsing infrastructure
  * =================================================
diff --git a/include/rdma/uverbs_named_ioctl.h b/include/rdma/uverbs_named_ioctl.h
index b3b21733cc55..b586e7c41d4a 100644
--- a/include/rdma/uverbs_named_ioctl.h
+++ b/include/rdma/uverbs_named_ioctl.h
@@ -102,18 +102,11 @@
 #define ADD_UVERBS_METHODS(_name, _object_id, ...)                             \
 	static const struct uverbs_method_def *const UVERBS_OBJECT_METHODS(    \
 		_object_id)[] = { __VA_ARGS__ };                               \
-	static const struct uverbs_object_def _name##_struct = {               \
+	static const struct uverbs_object_def _name = {                        \
 		.id = _object_id,                                              \
 		.num_methods = ARRAY_SIZE(UVERBS_OBJECT_METHODS(_object_id)),  \
 		.methods = &UVERBS_OBJECT_METHODS(_object_id)                  \
-	};                                                                     \
-	static const struct uverbs_object_def *const _name##_ptrs[] = {        \
-		&_name##_struct,                                               \
-	};                                                                     \
-	static const struct uverbs_object_tree_def _name = {                   \
-		.num_objects = 1,                                              \
-		.objects = &_name##_ptrs,                                      \
-	}
+	};
 
 /* Used by drivers to declare a complete parsing tree for a single method that
  * differs only in having additional driver specific attributes.
diff --git a/include/rdma/uverbs_std_types.h b/include/rdma/uverbs_std_types.h
index 3db2802fbc68..e3154f8d3cda 100644
--- a/include/rdma/uverbs_std_types.h
+++ b/include/rdma/uverbs_std_types.h
@@ -37,15 +37,6 @@
 #include <rdma/uverbs_ioctl.h>
 #include <rdma/ib_user_ioctl_verbs.h>
 
-#if IS_ENABLED(CONFIG_INFINIBAND_USER_ACCESS)
-const struct uverbs_object_tree_def *uverbs_default_get_objects(void);
-#else
-static inline const struct uverbs_object_tree_def *uverbs_default_get_objects(void)
-{
-	return NULL;
-}
-#endif
-
 /* Returns _id, or causes a compile error if _id is not a u32.
  *
  * The uobj APIs should only be used with the write based uAPI to access