[Intel-gfx] [RFC PATCH 02/11] drm/i915: add a helper to free the members of i915_params

[Jani Nikula]

Abstract the one user in anticipation of more. Set the dangling pointers
to NULL while at it.

Signed-off-by: Jani Nikula <jani.nikula at intel.com>
---
 drivers/gpu/drm/i915/i915_gpu_error.c |  9 +--------
 drivers/gpu/drm/i915/i915_params.c    | 16 ++++++++++++++++
 drivers/gpu/drm/i915/i915_params.h    |  1 +
 3 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c
index 8c04479c1586..2bd7991ec9af 100644
--- a/drivers/gpu/drm/i915/i915_gpu_error.c
+++ b/drivers/gpu/drm/i915/i915_gpu_error.c
@@ -963,17 +963,10 @@ static void i915_error_object_free(struct drm_i915_error_object *obj)
 	kfree(obj);
 }
 
-static __always_inline void free_param(const char *type, void *x)
-{
-	if (!__builtin_strcmp(type, "char *"))
-		kfree(*(void **)x);
-}
 
 static void cleanup_params(struct i915_gpu_state *error)
 {
-#define FREE(T, x, ...) free_param(#T, &error->params.x);
-	I915_PARAMS_FOR_EACH(FREE);
-#undef FREE
+	i915_params_free(&error->params);
 }
 
 static void cleanup_uc_state(struct i915_gpu_state *error)
diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
index ae3ece4ec7ab..81c73bfc7991 100644
--- a/drivers/gpu/drm/i915/i915_params.c
+++ b/drivers/gpu/drm/i915/i915_params.c
@@ -217,3 +217,19 @@ void i915_params_copy(struct i915_params *dest, const struct i915_params *src)
 	I915_PARAMS_FOR_EACH(DUP);
 #undef DUP
 }
+
+static __always_inline void free_param(const char *type, void *x)
+{
+	if (!__builtin_strcmp(type, "char *")) {
+		kfree(*(void **)x);
+		*(void **)x = NULL;
+	}
+}
+
+/* free the allocated members, *not* the passed in params itself */
+void i915_params_free(struct i915_params *params)
+{
+#define FREE(T, x, ...) free_param(#T, &params->x);
+	I915_PARAMS_FOR_EACH(FREE);
+#undef FREE
+}
diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h
index fd1cf9415e60..93f665eced16 100644
--- a/drivers/gpu/drm/i915/i915_params.h
+++ b/drivers/gpu/drm/i915/i915_params.h
@@ -79,6 +79,7 @@ extern struct i915_params i915_modparams __read_mostly;
 
 void i915_params_dump(const struct i915_params *params, struct drm_printer *p);
 void i915_params_copy(struct i915_params *dest, const struct i915_params *src);
+void i915_params_free(struct i915_params *params);
 
 #endif
 
-- 
2.11.0