drm: Introduce drm_mode_object_{get,put}()

For consistency with other reference counting APIs in the kernel, add drm_mode_object_get() and drm_mode_object_put() to reference count DRM mode objects. Compatibility aliases are added to keep existing code working. To help speed up the transition, all the instances of the old functions in the DRM core are already replaced in this commit. A semantic patch is provided that can be used to convert all drivers to the new helpers.

Thierry Reding committed 9 years ago

Commit 020a2181 parent 2135ea75 files · +95 −29Browse files

Unified · Split

5 files

drivers/gpu/drm/drm_atomic.c +7 −7
drivers/gpu/drm/drm_mode_object.c +13 −13
drivers/gpu/drm/drm_property.c +3 −3
include/drm/drm_mode_object.h +30 −6
scripts/coccinelle/api/drm-get-put.cocci +42 −0

drivers/gpu/drm/drm_atomic.c+7−7

@@ -2238,13 +2238,13 @@ retry: · 2237 unmodified lines
2238	}	2238	}
2239		2239
2240	if (!obj->properties) {	2240	if (!obj->properties) {
2241	drm_mode_object_unreference(obj);	2241	drm_mode_object_put(obj);
2242	ret = -ENOENT;	2242	ret = -ENOENT;
2243	goto out;	2243	goto out;
2244	}	2244	}
2245		2245
2246	if (get_user(count_props, count_props_ptr + copied_objs)) {	2246	if (get_user(count_props, count_props_ptr + copied_objs)) {
2247	drm_mode_object_unreference(obj);	2247	drm_mode_object_put(obj);
2248	ret = -EFAULT;	2248	ret = -EFAULT;
2249	goto out;	2249	goto out;
2250	}	2250	}
@@ -2257,14 +2257,14 @@ retry: · 6 unmodified lines
2257	struct drm_property *prop;	2257	struct drm_property *prop;
2258		2258
2259	if (get_user(prop_id, props_ptr + copied_props)) {	2259	if (get_user(prop_id, props_ptr + copied_props)) {
2260	drm_mode_object_unreference(obj);	2260	drm_mode_object_put(obj);
2261	ret = -EFAULT;	2261	ret = -EFAULT;
2262	goto out;	2262	goto out;
2263	}	2263	}
2264		2264
2265	prop = drm_mode_obj_find_prop_id(obj, prop_id);	2265	prop = drm_mode_obj_find_prop_id(obj, prop_id);
2266	if (!prop) {	2266	if (!prop) {
2267	drm_mode_object_unreference(obj);	2267	drm_mode_object_put(obj);
2268	ret = -ENOENT;	2268	ret = -ENOENT;
2269	goto out;	2269	goto out;
2270	}	2270	}
@@ -2272,14 +2272,14 @@ retry: · 1 unmodified line
2272	if (copy_from_user(&prop_value,	2272	if (copy_from_user(&prop_value,
2273	prop_values_ptr + copied_props,	2273	prop_values_ptr + copied_props,
2274	sizeof(prop_value))) {	2274	sizeof(prop_value))) {
2275	drm_mode_object_unreference(obj);	2275	drm_mode_object_put(obj);
2276	ret = -EFAULT;	2276	ret = -EFAULT;
2277	goto out;	2277	goto out;
2278	}	2278	}
2279		2279
2280	ret = atomic_set_prop(state, obj, prop, prop_value);	2280	ret = atomic_set_prop(state, obj, prop, prop_value);
2281	if (ret) {	2281	if (ret) {
2282	drm_mode_object_unreference(obj);	2282	drm_mode_object_put(obj);
2283	goto out;	2283	goto out;
2284	}	2284	}
2285		2285
@@ -2292,7 +2292,7 @@ retry: · 6 unmodified lines
2292	plane_mask \|= (1 << drm_plane_index(plane));	2292	plane_mask \|= (1 << drm_plane_index(plane));
2293	plane->old_fb = plane->fb;	2293	plane->old_fb = plane->fb;
2294	}	2294	}
2295	drm_mode_object_unreference(obj);	2295	drm_mode_object_put(obj);
2296	}	2296	}
2297		2297
2298	ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,	2298	ret = prepare_crtc_signaling(dev, state, arg, file_priv, &fence_state,

drivers/gpu/drm/drm_mode_object.c+13−13

@@ -133,7 +133,7 @@ struct drm_mode_object __drm_mode_object_find(struct drm_device dev, · 132 unmodified lines
133	*	133	*
134	* This function is used to look up a modeset object. It will acquire a	134	* This function is used to look up a modeset object. It will acquire a
135	* reference for reference counted objects. This reference must be dropped again	135	* reference for reference counted objects. This reference must be dropped again
136	* by callind drm_mode_object_unreference().	136	* by callind drm_mode_object_put().
137	*/	137	*/
138	struct drm_mode_object drm_mode_object_find(struct drm_device dev,	138	struct drm_mode_object drm_mode_object_find(struct drm_device dev,
139	uint32_t id, uint32_t type)	139	uint32_t id, uint32_t type)
@@ -146,38 +146,38 @@ struct drm_mode_object drm_mode_object_find(struct drm_device dev, · 6 unmodified lines
146	EXPORT_SYMBOL(drm_mode_object_find);	146	EXPORT_SYMBOL(drm_mode_object_find);
147		147
148	/**	148	/**
149	* drm_mode_object_unreference - decr the object refcnt	149	* drm_mode_object_put - release a mode object reference
150	* @obj: mode_object	150	* @obj: DRM mode object
151	*	151	*
152	* This function decrements the object's refcount if it is a refcounted modeset	152	* This function decrements the object's refcount if it is a refcounted modeset
153	* object. It is a no-op on any other object. This is used to drop references	153	* object. It is a no-op on any other object. This is used to drop references
154	* acquired with drm_mode_object_reference().	154	* acquired with drm_mode_object_get().
155	*/	155	*/
156	void drm_mode_object_unreference(struct drm_mode_object *obj)	156	void drm_mode_object_put(struct drm_mode_object *obj)
157	{	157	{
158	if (obj->free_cb) {	158	if (obj->free_cb) {
159	DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, atomic_read(&obj->refcount.refcount));	159	DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, atomic_read(&obj->refcount.refcount));
160	kref_put(&obj->refcount, obj->free_cb);	160	kref_put(&obj->refcount, obj->free_cb);
161	}	161	}
162	}	162	}
163	EXPORT_SYMBOL(drm_mode_object_unreference);	163	EXPORT_SYMBOL(drm_mode_object_put);
164		164
165	/**	165	/**
166	* drm_mode_object_reference - incr the object refcnt	166	* drm_mode_object_get - acquire a mode object reference
167	* @obj: mode_object	167	* @obj: DRM mode object
168	*	168	*
169	* This function increments the object's refcount if it is a refcounted modeset	169	* This function increments the object's refcount if it is a refcounted modeset
170	* object. It is a no-op on any other object. References should be dropped again	170	* object. It is a no-op on any other object. References should be dropped again
171	* by calling drm_mode_object_unreference().	171	* by calling drm_mode_object_put().
172	*/	172	*/
173	void drm_mode_object_reference(struct drm_mode_object *obj)	173	void drm_mode_object_get(struct drm_mode_object *obj)
174	{	174	{
175	if (obj->free_cb) {	175	if (obj->free_cb) {
176	DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, atomic_read(&obj->refcount.refcount));	176	DRM_DEBUG("OBJ ID: %d (%d)\n", obj->id, atomic_read(&obj->refcount.refcount));
177	kref_get(&obj->refcount);	177	kref_get(&obj->refcount);
178	}	178	}
179	}	179	}
180	EXPORT_SYMBOL(drm_mode_object_reference);	180	EXPORT_SYMBOL(drm_mode_object_get);
181		181
182	/**	182	/**
183	* drm_object_attach_property - attach a property to a modeset object	183	* drm_object_attach_property - attach a property to a modeset object
@@ -363,7 +363,7 @@ int drm_mode_obj_get_properties_ioctl(struct drm_device dev, void data, · 179 unmodified lines
363	&arg->count_props);	363	&arg->count_props);
364		364
365	out_unref:	365	out_unref:
366	drm_mode_object_unreference(obj);	366	drm_mode_object_put(obj);
367	out:	367	out:
368	drm_modeset_unlock_all(dev);	368	drm_modeset_unlock_all(dev);
369	return ret;	369	return ret;
@@ -428,7 +428,7 @@ int drm_mode_obj_set_property_ioctl(struct drm_device dev, void data, · 58 unmodified lines
428	drm_property_change_valid_put(property, ref);	428	drm_property_change_valid_put(property, ref);
429		429
430	out_unref:	430	out_unref:
431	drm_mode_object_unreference(arg_obj);	431	drm_mode_object_put(arg_obj);
432	out:	432	out:
433	drm_modeset_unlock_all(dev);	433	drm_modeset_unlock_all(dev);
434	return ret;	434	return ret;

drivers/gpu/drm/drm_property.c+3−3

@@ -597,7 +597,7 @@ void drm_property_unreference_blob(struct drm_property_blob *blob) · 596 unmodified lines
597	if (!blob)	597	if (!blob)
598	return;	598	return;
599		599
600	drm_mode_object_unreference(&blob->base);	600	drm_mode_object_put(&blob->base);
601	}	601	}
602	EXPORT_SYMBOL(drm_property_unreference_blob);	602	EXPORT_SYMBOL(drm_property_unreference_blob);
603		603
@@ -625,7 +625,7 @@ void drm_property_destroy_user_blobs(struct drm_device *dev, · 21 unmodified lines
625	*/	625	*/
626	struct drm_property_blob drm_property_reference_blob(struct drm_property_blob blob)	626	struct drm_property_blob drm_property_reference_blob(struct drm_property_blob blob)
627	{	627	{
628	drm_mode_object_reference(&blob->base);	628	drm_mode_object_get(&blob->base);
629	return blob;	629	return blob;
630	}	630	}
631	EXPORT_SYMBOL(drm_property_reference_blob);	631	EXPORT_SYMBOL(drm_property_reference_blob);
@@ -906,7 +906,7 @@ void drm_property_change_valid_put(struct drm_property *property, · 274 unmodified lines
906	return;	906	return;
907		907
908	if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {	908	if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
909	drm_mode_object_unreference(ref);	909	drm_mode_object_put(ref);
910	} else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB))	910	} else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB))
911	drm_property_unreference_blob(obj_to_blob(ref));	911	drm_property_unreference_blob(obj_to_blob(ref));
912	}	912	}

include/drm/drm_mode_object.h+30−6

@@ -45,10 +45,10 @@ struct drm_device; · 44 unmodified lines
45	* drm_object_attach_property() before the object is visible to userspace.	45	* drm_object_attach_property() before the object is visible to userspace.
46	*	46	*
47	* - For objects with dynamic lifetimes (as indicated by a non-NULL @free_cb) it	47	* - For objects with dynamic lifetimes (as indicated by a non-NULL @free_cb) it
48	* provides reference counting through drm_mode_object_reference() and	48	* provides reference counting through drm_mode_object_get() and
49	* drm_mode_object_unreference(). This is used by &drm_framebuffer,	49	* drm_mode_object_put(). This is used by &drm_framebuffer, &drm_connector
50	* &drm_connector and &drm_property_blob. These objects provide specialized	50	* and &drm_property_blob. These objects provide specialized reference
51	* reference counting wrappers.	51	* counting wrappers.
52	*/	52	*/
53	struct drm_mode_object {	53	struct drm_mode_object {
54	uint32_t id;	54	uint32_t id;
@@ -114,8 +114,32 @@ struct drm_object_properties { · 59 unmodified lines
114		114
115	struct drm_mode_object drm_mode_object_find(struct drm_device dev,	115	struct drm_mode_object drm_mode_object_find(struct drm_device dev,
116	uint32_t id, uint32_t type);	116	uint32_t id, uint32_t type);
117	void drm_mode_object_reference(struct drm_mode_object *obj);	117	void drm_mode_object_get(struct drm_mode_object *obj);
118	void drm_mode_object_unreference(struct drm_mode_object *obj);	118	void drm_mode_object_put(struct drm_mode_object *obj);
		119
		120	/**
		121	* drm_mode_object_reference - acquire a mode object reference
		122	* @obj: DRM mode object
		123	*
		124	* This is a compatibility alias for drm_mode_object_get() and should not be
		125	* used by new code.
		126	*/
		127	static inline void drm_mode_object_reference(struct drm_mode_object *obj)
		128	{
		129	drm_mode_object_get(obj);
		130	}
		131
		132	/**
		133	* drm_mode_object_unreference - release a mode object reference
		134	* @obj: DRM mode object
		135	*
		136	* This is a compatibility alias for drm_mode_object_put() and should not be
		137	* used by new code.
		138	*/
		139	static inline void drm_mode_object_unreference(struct drm_mode_object *obj)
		140	{
		141	drm_mode_object_put(obj);
		142	}
119		143
120	int drm_object_property_set_value(struct drm_mode_object *obj,	144	int drm_object_property_set_value(struct drm_mode_object *obj,
121	struct drm_property *property,	145	struct drm_property *property,

scripts/coccinelle/api/drm-get-put.cocci+42−0

@@ -0,0 +1,42 @@
	1	///
	2	/// Use drm__get() and drm__put() helpers instead of drm_*_reference() and
	3	/// drm_*_unreference() helpers.
	4	///
	5	// Confidence: High
	6	// Copyright: (C) 2017 NVIDIA Corporation
	7	// Options: --no-includes --include-headers
	8	//
	9
	10	virtual patch
	11	virtual report
	12
	13	@depends on patch@
	14	expression object;
	15	@@
	16
	17	(
	18	- drm_mode_object_reference(object)
	19	+ drm_mode_object_get(object)
	20	\|
	21	- drm_mode_object_unreference(object)
	22	+ drm_mode_object_put(object)
	23	)
	24
	25	@r depends on report@
	26	expression object;
	27	position p;
	28	@@
	29
	30	(
	31	drm_mode_object_unreference@p(object)
	32	\|
	33	drm_mode_object_reference@p(object)
	34	)
	35
	36	@script:python depends on report@
	37	object << r.object;
	38	p << r.p;
	39	@@
	40
	41	msg="WARNING: use get/put helpers to reference and dereference %s" % (object)
	42	coccilib.report.print_report(p[0], msg)