prepare for preparing for atomic (v2)

Add a few more useful helpers to find mode objects.

Signed-off-by Rob Clark <[email protected]>

---
 drivers/gpu/drm/drm_crtc.c | 90 +++++++++++++++-------------------------------
 include/drm/drm_crtc.h     | 33 +++++++++++++++++
 2 files changed, 61 insertions(+), 62 deletions(-)

drivers/gpu/drm/drm_crtc.c +28 -62

index 37a3e07..02872af 100644
@@ -1711,7 +1711,6 @@ int drm_mode_getcrtc(struct drm_device *dev,
 {
 	struct drm_mode_crtc *crtc_resp = data;
 	struct drm_crtc *crtc;
-	struct drm_mode_object *obj;
 	int ret = 0;
 
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))

@@ -1719,13 +1718,11 @@ int drm_mode_getcrtc(struct drm_device *dev,
 
 	drm_modeset_lock_all(dev);
 
-	obj = drm_mode_object_find(dev, crtc_resp->crtc_id,
-				   DRM_MODE_OBJECT_CRTC);
-	if (!obj) {
+	crtc = drm_crtc_find(dev, crtc_resp->crtc_id);
+	if (!crtc) {
 		ret = -ENOENT;
 		goto out;
 	}
-	crtc = obj_to_crtc(obj);
 
 	crtc_resp->x = crtc->x;
 	crtc_resp->y = crtc->y;

@@ -1779,7 +1776,6 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 			  struct drm_file *file_priv)
 {
 	struct drm_mode_get_connector *out_resp = data;
-	struct drm_mode_object *obj;
 	struct drm_connector *connector;
 	struct drm_display_mode *mode;
 	int mode_count = 0;

@@ -1803,13 +1799,11 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 
 	mutex_lock(&dev->mode_config.mutex);
 
-	obj = drm_mode_object_find(dev, out_resp->connector_id,
-				   DRM_MODE_OBJECT_CONNECTOR);
-	if (!obj) {
+	connector = drm_connector_find(dev, out_resp->connector_id);
+	if (!connector) {
 		ret = -ENOENT;
 		goto out;
 	}
-	connector = obj_to_connector(obj);
 
 	props_count = connector->properties.count;
 

@@ -1924,7 +1918,6 @@ int drm_mode_getencoder(struct drm_device *dev, void *data,
 			struct drm_file *file_priv)
 {
 	struct drm_mode_get_encoder *enc_resp = data;
-	struct drm_mode_object *obj;
 	struct drm_encoder *encoder;
 	int ret = 0;
 

@@ -1932,13 +1925,11 @@ int drm_mode_getencoder(struct drm_device *dev, void *data,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, enc_resp->encoder_id,
-				   DRM_MODE_OBJECT_ENCODER);
-	if (!obj) {
+	encoder = drm_encoder_find(dev, enc_resp->encoder_id);
+	if (!encoder) {
 		ret = -ENOENT;
 		goto out;
 	}
-	encoder = obj_to_encoder(obj);
 
 	if (encoder->crtc)
 		enc_resp->crtc_id = encoder->crtc->base.id;

@@ -2036,7 +2027,6 @@ int drm_mode_getplane(struct drm_device *dev, void *data,
 		      struct drm_file *file_priv)
 {
 	struct drm_mode_get_plane *plane_resp = data;
-	struct drm_mode_object *obj;
 	struct drm_plane *plane;
 	uint32_t __user *format_ptr;
 	int ret = 0;

@@ -2045,13 +2035,11 @@ int drm_mode_getplane(struct drm_device *dev, void *data,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, plane_resp->plane_id,
-				   DRM_MODE_OBJECT_PLANE);
-	if (!obj) {
+	plane = drm_plane_find(dev, plane_resp->plane_id);
+	if (!plane) {
 		ret = -ENOENT;
 		goto out;
 	}
-	plane = obj_to_plane(obj);
 
 	if (plane->crtc)
 		plane_resp->crtc_id = plane->crtc->base.id;

@@ -2104,7 +2092,6 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
 		      struct drm_file *file_priv)
 {
 	struct drm_mode_set_plane *plane_req = data;
-	struct drm_mode_object *obj;
 	struct drm_plane *plane;
 	struct drm_crtc *crtc;
 	struct drm_framebuffer *fb = NULL, *old_fb = NULL;

@@ -2119,14 +2106,12 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
 	 * First, find the plane, crtc, and fb objects.  If not available,
 	 * we don't bother to call the driver.
 	 */
-	obj = drm_mode_object_find(dev, plane_req->plane_id,
-				   DRM_MODE_OBJECT_PLANE);
-	if (!obj) {
+	plane = drm_plane_find(dev, plane_req->plane_id);
+	if (!plane) {
 		DRM_DEBUG_KMS("Unknown plane ID %d\n",
 			      plane_req->plane_id);
 		return -ENOENT;
 	}
-	plane = obj_to_plane(obj);
 
 	/* No fb means shut it down */
 	if (!plane_req->fb_id) {

@@ -2143,15 +2128,13 @@ int drm_mode_setplane(struct drm_device *dev, void *data,
 		goto out;
 	}
 
-	obj = drm_mode_object_find(dev, plane_req->crtc_id,
-				   DRM_MODE_OBJECT_CRTC);
-	if (!obj) {
+	crtc = drm_crtc_find(dev, plane_req->crtc_id);
+	if (!crtc) {
 		DRM_DEBUG_KMS("Unknown crtc ID %d\n",
 			      plane_req->crtc_id);
 		ret = -ENOENT;
 		goto out;
 	}
-	crtc = obj_to_crtc(obj);
 
 	fb = drm_framebuffer_lookup(dev, plane_req->fb_id);
 	if (!fb) {

@@ -2338,7 +2321,6 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
 {
 	struct drm_mode_config *config = &dev->mode_config;
 	struct drm_mode_crtc *crtc_req = data;
-	struct drm_mode_object *obj;
 	struct drm_crtc *crtc;
 	struct drm_connector **connector_set = NULL, *connector;
 	struct drm_framebuffer *fb = NULL;

@@ -2356,14 +2338,12 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
 		return -ERANGE;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, crtc_req->crtc_id,
-				   DRM_MODE_OBJECT_CRTC);
-	if (!obj) {
+	crtc = drm_crtc_find(dev, crtc_req->crtc_id);
+	if (!crtc) {
 		DRM_DEBUG_KMS("Unknown CRTC ID %d\n", crtc_req->crtc_id);
 		ret = -ENOENT;
 		goto out;
 	}
-	crtc = obj_to_crtc(obj);
 	DRM_DEBUG_KMS("[CRTC:%d]\n", crtc->base.id);
 
 	if (crtc_req->mode_valid) {

@@ -2446,15 +2426,13 @@ int drm_mode_setcrtc(struct drm_device *dev, void *data,
 				goto out;
 			}
 
-			obj = drm_mode_object_find(dev, out_id,
-						   DRM_MODE_OBJECT_CONNECTOR);
-			if (!obj) {
+			connector = drm_connector_find(dev, out_id);
+			if (!connector) {
 				DRM_DEBUG_KMS("Connector id %d unknown\n",
 						out_id);
 				ret = -ENOENT;
 				goto out;
 			}
-			connector = obj_to_connector(obj);
 			DRM_DEBUG_KMS("[CONNECTOR:%d:%s]\n",
 					connector->base.id,
 					drm_get_connector_name(connector));

@@ -2486,7 +2464,6 @@ static int drm_mode_cursor_common(struct drm_device *dev,
 				  struct drm_mode_cursor2 *req,
 				  struct drm_file *file_priv)
 {
-	struct drm_mode_object *obj;
 	struct drm_crtc *crtc;
 	int ret = 0;
 

@@ -2496,12 +2473,11 @@ static int drm_mode_cursor_common(struct drm_device *dev,
 	if (!req->flags || (~DRM_MODE_CURSOR_FLAGS & req->flags))
 		return -EINVAL;
 
-	obj = drm_mode_object_find(dev, req->crtc_id, DRM_MODE_OBJECT_CRTC);
-	if (!obj) {
+	crtc = drm_crtc_find(dev, req->crtc_id);
+	if (!crtc) {
 		DRM_DEBUG_KMS("Unknown CRTC ID %d\n", req->crtc_id);
 		return -ENOENT;
 	}
-	crtc = obj_to_crtc(obj);
 
 	mutex_lock(&crtc->mutex);
 	if (req->flags & DRM_MODE_CURSOR_BO) {

@@ -3458,7 +3434,6 @@ EXPORT_SYMBOL(drm_object_property_get_value);
 int drm_mode_getproperty_ioctl(struct drm_device *dev,
 			       void *data, struct drm_file *file_priv)
 {
-	struct drm_mode_object *obj;
 	struct drm_mode_get_property *out_resp = data;
 	struct drm_property *property;
 	int enum_count = 0;

@@ -3477,12 +3452,11 @@ int drm_mode_getproperty_ioctl(struct drm_device *dev,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, out_resp->prop_id, DRM_MODE_OBJECT_PROPERTY);
-	if (!obj) {
+	property = drm_property_find(dev, out_resp->prop_id);
+	if (!property) {
 		ret = -ENOENT;
 		goto done;
 	}
-	property = obj_to_property(obj);
 
 	if (property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)) {
 		list_for_each_entry(prop_enum, &property->enum_blob_list, head)

@@ -3610,7 +3584,6 @@ static void drm_property_destroy_blob(struct drm_device *dev,
 int drm_mode_getblob_ioctl(struct drm_device *dev,
 			   void *data, struct drm_file *file_priv)
 {
-	struct drm_mode_object *obj;
 	struct drm_mode_get_blob *out_resp = data;
 	struct drm_property_blob *blob;
 	int ret = 0;

@@ -3620,12 +3593,11 @@ int drm_mode_getblob_ioctl(struct drm_device *dev,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, out_resp->blob_id, DRM_MODE_OBJECT_BLOB);
-	if (!obj) {
+	blob = drm_property_blob_find(dev, out_resp->blob_id);
+	if (!blob) {
 		ret = -ENOENT;
 		goto done;
 	}
-	blob = obj_to_blob(obj);
 
 	if (out_resp->length == blob->length) {
 		blob_ptr = (void __user *)(unsigned long)out_resp->data;

@@ -4007,7 +3979,6 @@ int drm_mode_gamma_set_ioctl(struct drm_device *dev,
 			     void *data, struct drm_file *file_priv)
 {
 	struct drm_mode_crtc_lut *crtc_lut = data;
-	struct drm_mode_object *obj;
 	struct drm_crtc *crtc;
 	void *r_base, *g_base, *b_base;
 	int size;

@@ -4017,12 +3988,11 @@ int drm_mode_gamma_set_ioctl(struct drm_device *dev,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, crtc_lut->crtc_id, DRM_MODE_OBJECT_CRTC);
-	if (!obj) {
+	crtc = drm_crtc_find(dev, crtc_lut->crtc_id);
+	if (!crtc) {
 		ret = -ENOENT;
 		goto out;
 	}
-	crtc = obj_to_crtc(obj);
 
 	if (crtc->funcs->gamma_set == NULL) {
 		ret = -ENOSYS;

@@ -4081,7 +4051,6 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 			     void *data, struct drm_file *file_priv)
 {
 	struct drm_mode_crtc_lut *crtc_lut = data;
-	struct drm_mode_object *obj;
 	struct drm_crtc *crtc;
 	void *r_base, *g_base, *b_base;
 	int size;

@@ -4091,12 +4060,11 @@ int drm_mode_gamma_get_ioctl(struct drm_device *dev,
 		return -EINVAL;
 
 	drm_modeset_lock_all(dev);
-	obj = drm_mode_object_find(dev, crtc_lut->crtc_id, DRM_MODE_OBJECT_CRTC);
-	if (!obj) {
+	crtc = drm_crtc_find(dev, crtc_lut->crtc_id);
+	if (!crtc) {
 		ret = -ENOENT;
 		goto out;
 	}
-	crtc = obj_to_crtc(obj);
 
 	/* memcpy into gamma store */
 	if (crtc_lut->gamma_size != crtc->gamma_size) {

@@ -4149,7 +4117,6 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 			     void *data, struct drm_file *file_priv)
 {
 	struct drm_mode_crtc_page_flip *page_flip = data;
-	struct drm_mode_object *obj;
 	struct drm_crtc *crtc;
 	struct drm_framebuffer *fb = NULL, *old_fb = NULL;
 	struct drm_pending_vblank_event *e = NULL;

@@ -4163,10 +4130,9 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 	if ((page_flip->flags & DRM_MODE_PAGE_FLIP_ASYNC) && !dev->mode_config.async_page_flip)
 		return -EINVAL;
 
-	obj = drm_mode_object_find(dev, page_flip->crtc_id, DRM_MODE_OBJECT_CRTC);
-	if (!obj)
+	crtc = drm_crtc_find(dev, page_flip->crtc_id);
+	if (!crtc)
 		return -ENOENT;
-	crtc = obj_to_crtc(obj);
 
 	mutex_lock(&crtc->mutex);
 	if (crtc->primary->fb == NULL) {

include/drm/drm_crtc.h +33 -0

index 5c1c31c..cdd5687 100644
@@ -1063,6 +1063,15 @@ extern int drm_format_vert_chroma_subsampling(uint32_t format);
 extern const char *drm_get_format_name(uint32_t format);
 
 /* Helpers */
+
+static inline struct drm_plane *drm_plane_find(struct drm_device *dev,
+		uint32_t id)
+{
+	struct drm_mode_object *mo;
+	mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_PLANE);
+	return mo ? obj_to_plane(mo) : NULL;
+}
+
 static inline struct drm_crtc *drm_crtc_find(struct drm_device *dev,
 	uint32_t id)
 {

@@ -1079,6 +1088,30 @@ static inline struct drm_encoder *drm_encoder_find(struct drm_device *dev,
 	return mo ? obj_to_encoder(mo) : NULL;
 }
 
+static inline struct drm_connector *drm_connector_find(struct drm_device *dev,
+		uint32_t id)
+{
+	struct drm_mode_object *mo;
+	mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_CONNECTOR);
+	return mo ? obj_to_connector(mo) : NULL;
+}
+
+static inline struct drm_property *drm_property_find(struct drm_device *dev,
+		uint32_t id)
+{
+	struct drm_mode_object *mo;
+	mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_PROPERTY);
+	return mo ? obj_to_property(mo) : NULL;
+}
+
+static inline struct drm_property_blob *
+drm_property_blob_find(struct drm_device *dev, uint32_t id)
+{
+	struct drm_mode_object *mo;
+	mo = drm_mode_object_find(dev, id, DRM_MODE_OBJECT_BLOB);
+	return mo ? obj_to_blob(mo) : NULL;
+}
+
 /* Plane list iterator for legacy (overlay only) planes. */
 #define drm_for_each_legacy_plane(plane, planelist) \
 	list_for_each_entry(plane, planelist, head) \

Signature · 1 line

1.9.3

If we continue to use bitmask for type, we will quickly run out of room to add new types. Split this up so existing part of bitmask range continues to function as before, but reserve a chunk of the remaining space for an integer type-id. Wrap this all up in some type-check helpers to keep the backwards-compat uglyness contained.

Signed-off-by Rob Clark <[email protected]>

---
 drivers/gpu/drm/drm_crtc.c  | 26 +++++++++++++++++---------
 include/drm/drm_crtc.h      | 17 +++++++++++++++++
 include/uapi/drm/drm_mode.h | 13 +++++++++++++
 3 files changed, 47 insertions(+), 9 deletions(-)

drivers/gpu/drm/drm_crtc.c +17 -9

index 02872af..0dbd6e0 100644
@@ -3113,6 +3113,9 @@ struct drm_property *drm_property_create(struct drm_device *dev, int flags,
 	}
 
 	list_add_tail(&property->head, &dev->mode_config.property_list);
+
+	WARN_ON(!drm_property_type_valid(property));
+
 	return property;
 fail:
 	kfree(property->values);

@@ -3270,14 +3273,16 @@ int drm_property_add_enum(struct drm_property *property, int index,
 {
 	struct drm_property_enum *prop_enum;
 
-	if (!(property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)))
+	if (!(drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
+			drm_property_type_is(property, DRM_MODE_PROP_BITMASK)))
 		return -EINVAL;
 
 	/*
 	 * Bitmask enum properties have the additional constraint of values
 	 * from 0 to 63
 	 */
-	if ((property->flags & DRM_MODE_PROP_BITMASK) && (value > 63))
+	if (drm_property_type_is(property, DRM_MODE_PROP_BITMASK) &&
+			(value > 63))
 		return -EINVAL;
 
 	if (!list_empty(&property->enum_blob_list)) {

@@ -3458,10 +3463,11 @@ int drm_mode_getproperty_ioctl(struct drm_device *dev,
 		goto done;
 	}
 
-	if (property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)) {
+	if (drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
+			drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
 		list_for_each_entry(prop_enum, &property->enum_blob_list, head)
 			enum_count++;
-	} else if (property->flags & DRM_MODE_PROP_BLOB) {
+	} else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
 		list_for_each_entry(prop_blob, &property->enum_blob_list, head)
 			blob_count++;
 	}

@@ -3483,7 +3489,8 @@ int drm_mode_getproperty_ioctl(struct drm_device *dev,
 	}
 	out_resp->count_values = value_count;
 
-	if (property->flags & (DRM_MODE_PROP_ENUM | DRM_MODE_PROP_BITMASK)) {
+	if (drm_property_type_is(property, DRM_MODE_PROP_ENUM) ||
+			drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
 		if ((out_resp->count_enum_blobs >= enum_count) && enum_count) {
 			copied = 0;
 			enum_ptr = (struct drm_mode_property_enum __user *)(unsigned long)out_resp->enum_blob_ptr;

@@ -3505,7 +3512,7 @@ int drm_mode_getproperty_ioctl(struct drm_device *dev,
 		out_resp->count_enum_blobs = enum_count;
 	}
 
-	if (property->flags & DRM_MODE_PROP_BLOB) {
+	if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
 		if ((out_resp->count_enum_blobs >= blob_count) && blob_count) {
 			copied = 0;
 			blob_id_ptr = (uint32_t __user *)(unsigned long)out_resp->enum_blob_ptr;

@@ -3659,17 +3666,18 @@ static bool drm_property_change_is_valid(struct drm_property *property,
 {
 	if (property->flags & DRM_MODE_PROP_IMMUTABLE)
 		return false;
-	if (property->flags & DRM_MODE_PROP_RANGE) {
+
+	if (drm_property_type_is(property, DRM_MODE_PROP_RANGE)) {
 		if (value < property->values[0] || value > property->values[1])
 			return false;
 		return true;
-	} else if (property->flags & DRM_MODE_PROP_BITMASK) {
+	} else if (drm_property_type_is(property, DRM_MODE_PROP_BITMASK)) {
 		int i;
 		uint64_t valid_mask = 0;
 		for (i = 0; i < property->num_values; i++)
 			valid_mask |= (1ULL << property->values[i]);
 		return !(value & ~valid_mask);
-	} else if (property->flags & DRM_MODE_PROP_BLOB) {
+	} else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
 		/* Only the driver knows */
 		return true;
 	} else {

include/drm/drm_crtc.h +17 -0

index cdd5687..0ff9558 100644
@@ -931,6 +931,23 @@ extern void drm_mode_config_cleanup(struct drm_device *dev);
 
 extern int drm_mode_connector_update_edid_property(struct drm_connector *connector,
 						struct edid *edid);
+
+static inline bool drm_property_type_is(struct drm_property *property,
+		uint32_t type)
+{
+	/* instanceof for props.. handles extended type vs original types: */
+	if (property->flags & DRM_MODE_PROP_EXTENDED_TYPE)
+		return (property->flags & DRM_MODE_PROP_EXTENDED_TYPE) == type;
+	return property->flags & type;
+}
+
+static inline bool drm_property_type_valid(struct drm_property *property)
+{
+	if (property->flags & DRM_MODE_PROP_EXTENDED_TYPE)
+		return !(property->flags & DRM_MODE_PROP_LEGACY_TYPE);
+	return !!(property->flags & DRM_MODE_PROP_LEGACY_TYPE);
+}
+
 extern int drm_object_property_set_value(struct drm_mode_object *obj,
 					 struct drm_property *property,
 					 uint64_t val);

include/uapi/drm/drm_mode.h +13 -0

index f104c26..a7f546e 100644
@@ -251,6 +251,19 @@ struct drm_mode_get_connector {
 #define DRM_MODE_PROP_BLOB	(1<<4)
 #define DRM_MODE_PROP_BITMASK	(1<<5) /* bitmask of enumerated types */
 
+/* non-extended types: legacy bitmask, one bit per type: */
+#define DRM_MODE_PROP_LEGACY_TYPE  ( \
+		DRM_MODE_PROP_RANGE | \
+		DRM_MODE_PROP_ENUM | \
+		DRM_MODE_PROP_BLOB | \
+		DRM_MODE_PROP_BITMASK)
+
+/* extended-types: rather than continue to consume a bit per type,
+ * grab a chunk of the bits to use as integer type id.
+ */
+#define DRM_MODE_PROP_EXTENDED_TYPE	0x0000ffc0
+#define DRM_MODE_PROP_TYPE(n)		((n) << 6)
+
 struct drm_mode_property_enum {
 	__u64 value;
 	char name[DRM_PROP_NAME_LEN];

Signature · 1 line

1.9.3

An object property is an id (idr) for a drm mode object. This will allow a property to be used set/get a framebuffer, CRTC, etc.

Signed-off-by Rob Clark <[email protected]>

---
 drivers/gpu/drm/drm_crtc.c  | 61 +++++++++++++++++++++++++++++++++++++++------
 include/drm/drm_crtc.h      |  5 ++++
 include/uapi/drm/drm_mode.h |  1 +
 3 files changed, 60 insertions(+), 7 deletions(-)

drivers/gpu/drm/drm_crtc.c +54 -7

index 0dbd6e0..8fdd5b3 100644
@@ -389,6 +389,21 @@ void drm_mode_object_put(struct drm_device *dev,
 	mutex_unlock(&dev->mode_config.idr_mutex);
 }
 
+static struct drm_mode_object *_object_find(struct drm_device *dev,
+		uint32_t id, uint32_t type)
+{
+	struct drm_mode_object *obj = NULL;
+
+	mutex_lock(&dev->mode_config.idr_mutex);
+	obj = idr_find(&dev->mode_config.crtc_idr, id);
+	if (!obj || (type != DRM_MODE_OBJECT_ANY && obj->type != type) ||
+	    (obj->id != id))
+		obj = NULL;
+	mutex_unlock(&dev->mode_config.idr_mutex);
+
+	return obj;
+}
+
 /**
  * drm_mode_object_find - look up a drm object with static lifetime
  * @dev: drm device

@@ -396,7 +411,9 @@ void drm_mode_object_put(struct drm_device *dev,
  * @type: type of the mode object
  *
  * Note that framebuffers cannot be looked up with this functions - since those
- * are reference counted, they need special treatment.
+ * are reference counted, they need special treatment.  Even with
+ * DRM_MODE_OBJECT_ANY (although that will simply return NULL
+ * rather than WARN_ON()).
  */
 struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
 		uint32_t id, uint32_t type)

@@ -406,13 +423,10 @@ struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
 	/* Framebuffers are reference counted and need their own lookup
 	 * function.*/
 	WARN_ON(type == DRM_MODE_OBJECT_FB);
-
-	mutex_lock(&dev->mode_config.idr_mutex);
-	obj = idr_find(&dev->mode_config.crtc_idr, id);
-	if (!obj || (obj->type != type) || (obj->id != id))
+	obj = _object_find(dev, id, type);
+	/* don't leak out unref'd fb's */
+	if (obj && (obj->type == DRM_MODE_OBJECT_FB))
 		obj = NULL;
-	mutex_unlock(&dev->mode_config.idr_mutex);
-
 	return obj;
 }
 EXPORT_SYMBOL(drm_mode_object_find);

@@ -3093,6 +3107,8 @@ struct drm_property *drm_property_create(struct drm_device *dev, int flags,
 	if (!property)
 		return NULL;
 
+	property->dev = dev;
+
 	if (num_values) {
 		property->values = kzalloc(sizeof(uint64_t)*num_values, GFP_KERNEL);
 		if (!property->values)

@@ -3253,6 +3269,23 @@ struct drm_property *drm_property_create_range(struct drm_device *dev, int flags
 }
 EXPORT_SYMBOL(drm_property_create_range);
 
+struct drm_property *drm_property_create_object(struct drm_device *dev,
+					 int flags, const char *name, uint32_t type)
+{
+	struct drm_property *property;
+
+	flags |= DRM_MODE_PROP_OBJECT;
+
+	property = drm_property_create(dev, flags, name, 1);
+	if (!property)
+		return NULL;
+
+	property->values[0] = type;
+
+	return property;
+}
+EXPORT_SYMBOL(drm_property_create_object);
+
 /**
  * drm_property_add_enum - add a possible value to an enumeration property
  * @property: enumeration property to change

@@ -3680,6 +3713,20 @@ static bool drm_property_change_is_valid(struct drm_property *property,
 	} else if (drm_property_type_is(property, DRM_MODE_PROP_BLOB)) {
 		/* Only the driver knows */
 		return true;
+	} else if (drm_property_type_is(property, DRM_MODE_PROP_OBJECT)) {
+		struct drm_mode_object *obj;
+		/* a zero value for an object property translates to null: */
+		if (value == 0)
+			return true;
+		/*
+		 * NOTE: use _object_find() directly to bypass restriction on
+		 * looking up refcnt'd objects (ie. fb's).  For a refcnt'd
+		 * object this could race against object finalization, so it
+		 * simply tells us that the object *was* valid.  Which is good
+		 * enough.
+		 */
+		obj = _object_find(property->dev, value, property->values[0]);
+		return obj != NULL;
 	} else {
 		int i;
 		for (i = 0; i < property->num_values; i++)

include/drm/drm_crtc.h +5 -0

index 0ff9558..c63df87 100644
@@ -50,6 +50,7 @@ struct drm_clip_rect;
 #define DRM_MODE_OBJECT_BLOB 0xbbbbbbbb
 #define DRM_MODE_OBJECT_PLANE 0xeeeeeeee
 #define DRM_MODE_OBJECT_BRIDGE 0xbdbdbdbd
+#define DRM_MODE_OBJECT_ANY 0
 
 struct drm_mode_object {
 	uint32_t id;

@@ -190,6 +191,7 @@ struct drm_property {
 	char name[DRM_PROP_NAME_LEN];
 	uint32_t num_values;
 	uint64_t *values;
+	struct drm_device *dev;
 
 	struct list_head enum_blob_list;
 };

@@ -981,6 +983,8 @@ struct drm_property *drm_property_create_bitmask(struct drm_device *dev,
 struct drm_property *drm_property_create_range(struct drm_device *dev, int flags,
 					 const char *name,
 					 uint64_t min, uint64_t max);
+struct drm_property *drm_property_create_object(struct drm_device *dev,
+					 int flags, const char *name, uint32_t type);
 extern void drm_property_destroy(struct drm_device *dev, struct drm_property *property);
 extern int drm_property_add_enum(struct drm_property *property, int index,
 				 uint64_t value, const char *name);

@@ -997,6 +1001,7 @@ extern int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 					 int gamma_size);
 extern struct drm_mode_object *drm_mode_object_find(struct drm_device *dev,
 		uint32_t id, uint32_t type);
+
 /* IOCTLs */
 extern int drm_mode_getresources(struct drm_device *dev,
 				 void *data, struct drm_file *file_priv);

include/uapi/drm/drm_mode.h +1 -0

index a7f546e..5b530c7 100644
@@ -263,6 +263,7 @@ struct drm_mode_get_connector {
  */
 #define DRM_MODE_PROP_EXTENDED_TYPE	0x0000ffc0
 #define DRM_MODE_PROP_TYPE(n)		((n) << 6)
+#define DRM_MODE_PROP_OBJECT		DRM_MODE_PROP_TYPE(1)
 
 struct drm_mode_property_enum {
 	__u64 value;

Signature · 1 line

1.9.3

For atomic, it will be quite necessary to not need to care so much about locking order. And 'state' gives us a convenient place to stash a ww_ctx for any sort of update that needs to grab multiple crtc locks.

Because we will want to eventually make locking even more fine grained (giving locks to planes, connectors, etc), split out drm_modeset_lock and drm_modeset_acquire_ctx to track acquired locks.

Atomic will use this to keep track of which locks have been acquired in a transaction.

v1: original
v2: remove a few things not needed until atomic, for now
v3: update for v3 of connection_mutex patch..

Signed-off-by Rob Clark <[email protected]>

---
 drivers/gpu/drm/Makefile              |   2 +-
 drivers/gpu/drm/drm_crtc.c            |  85 +++++++++++-----
 drivers/gpu/drm/drm_crtc_helper.c     |   3 +-
 drivers/gpu/drm/drm_fb_helper.c       |   4 +
 drivers/gpu/drm/drm_modeset_lock.c    | 179 ++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/drm_plane_helper.c    |   2 +-
 drivers/gpu/drm/i915/intel_crt.c      |   5 +-
 drivers/gpu/drm/i915/intel_display.c  |  58 +++++++----
 drivers/gpu/drm/i915/intel_dp.c       |  14 +--
 drivers/gpu/drm/i915/intel_drv.h      |   6 +-
 drivers/gpu/drm/i915/intel_opregion.c |   4 +-
 drivers/gpu/drm/i915/intel_overlay.c  |   4 +-
 drivers/gpu/drm/i915/intel_panel.c    |   8 +-
 drivers/gpu/drm/i915/intel_sprite.c   |   2 +-
 drivers/gpu/drm/i915/intel_tv.c       |   5 +-
 drivers/gpu/drm/omapdrm/omap_crtc.c   |  10 +-
 drivers/gpu/drm/vmwgfx/vmwgfx_kms.c   |   8 +-
 include/drm/drmP.h                    |   5 -
 include/drm/drm_crtc.h                |  15 +--
 include/drm/drm_modeset_lock.h        | 103 +++++++++++++++++++
 20 files changed, 434 insertions(+), 88 deletions(-)
 create mode 100644 drivers/gpu/drm/drm_modeset_lock.c
 create mode 100644 include/drm/drm_modeset_lock.h

drivers/gpu/drm/Makefile +1 -1

index 48e38ba..bf4c12d 100644
@@ -14,7 +14,7 @@ drm-y       :=	drm_auth.o drm_buffer.o drm_bufs.o drm_cache.o \
 		drm_info.o drm_debugfs.o drm_encoder_slave.o \
 		drm_trace_points.o drm_global.o drm_prime.o \
 		drm_rect.o drm_vma_manager.o drm_flip_work.o \
-		drm_plane_helper.o
+		drm_plane_helper.o drm_modeset_lock.o
 
 drm-$(CONFIG_COMPAT) += drm_ioc32.o
 drm-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_gem_cma_helper.o

drivers/gpu/drm/drm_crtc.c +63 -22

index bbb329f..186bed4 100644
@@ -37,6 +37,7 @@
 #include <drm/drm_crtc.h>
 #include <drm/drm_edid.h>
 #include <drm/drm_fourcc.h>
+#include <drm/drm_modeset_lock.h>
 
 #include "drm_crtc_internal.h"
 

@@ -50,14 +51,42 @@
  */
 void drm_modeset_lock_all(struct drm_device *dev)
 {
-	struct drm_crtc *crtc;
+	struct drm_mode_config *config = &dev->mode_config;
+	struct drm_modeset_acquire_ctx *ctx;
+	int ret;
 
-	mutex_lock(&dev->mode_config.mutex);
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (WARN_ON(!ctx))
+		return;
 
-	mutex_lock(&dev->mode_config.connection_mutex);
+	mutex_lock(&config->mutex);
 
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
-		mutex_lock_nest_lock(&crtc->mutex, &dev->mode_config.mutex);
+	drm_modeset_acquire_init(ctx, 0);
+
+retry:
+	ret = drm_modeset_lock(&config->connection_mutex, ctx);
+	if (ret)
+		goto fail;
+	ret = drm_modeset_lock_all_crtcs(dev, ctx);
+	if (ret)
+		goto fail;
+
+	WARN_ON(config->acquire_ctx);
+
+	/* now we hold the locks, so now that it is safe, stash the
+	 * ctx for drm_modeset_unlock_all():
+	 */
+	config->acquire_ctx = ctx;
+
+	drm_warn_on_modeset_not_all_locked(dev);
+
+	return;
+
+fail:
+	if (ret == -EDEADLK) {
+		drm_modeset_backoff(ctx);
+		goto retry;
+	}
 }
 EXPORT_SYMBOL(drm_modeset_lock_all);
 

@@ -69,12 +98,17 @@ EXPORT_SYMBOL(drm_modeset_lock_all);
  */
 void drm_modeset_unlock_all(struct drm_device *dev)
 {
-	struct drm_crtc *crtc;
+	struct drm_mode_config *config = &dev->mode_config;
+	struct drm_modeset_acquire_ctx *ctx = config->acquire_ctx;
 
-	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
-		mutex_unlock(&crtc->mutex);
+	if (WARN_ON(!ctx))
+		return;
+
+	config->acquire_ctx = NULL;
+	drm_modeset_drop_locks(ctx);
+	drm_modeset_acquire_fini(ctx);
 
-	mutex_unlock(&dev->mode_config.connection_mutex);
+	kfree(ctx);
 
 	mutex_unlock(&dev->mode_config.mutex);
 }

@@ -95,9 +129,9 @@ void drm_warn_on_modeset_not_all_locked(struct drm_device *dev)
 		return;
 
 	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head)
-		WARN_ON(!mutex_is_locked(&crtc->mutex));
+		WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
 
-	WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
+	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
 }
 EXPORT_SYMBOL(drm_warn_on_modeset_not_all_locked);

@@ -690,6 +724,8 @@ void drm_framebuffer_remove(struct drm_framebuffer *fb)
 }
 EXPORT_SYMBOL(drm_framebuffer_remove);
 
+DEFINE_WW_CLASS(crtc_ww_class);
+
 /**
  * drm_crtc_init_with_planes - Initialise a new CRTC object with
  *    specified primary and cursor planes.

@@ -709,6 +745,7 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
 			      void *cursor,
 			      const struct drm_crtc_funcs *funcs)
 {
+	struct drm_mode_config *config = &dev->mode_config;
 	int ret;
 
 	crtc->dev = dev;

@@ -716,8 +753,9 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
 	crtc->invert_dimensions = false;
 
 	drm_modeset_lock_all(dev);
-	mutex_init(&crtc->mutex);
-	mutex_lock_nest_lock(&crtc->mutex, &dev->mode_config.mutex);
+	drm_modeset_lock_init(&crtc->mutex);
+	/* dropped by _unlock_all(): */
+	drm_modeset_lock(&crtc->mutex, config->acquire_ctx);
 
 	ret = drm_mode_object_get(dev, &crtc->base, DRM_MODE_OBJECT_CRTC);
 	if (ret)

@@ -725,8 +763,8 @@ int drm_crtc_init_with_planes(struct drm_device *dev, struct drm_crtc *crtc,
 
 	crtc->base.properties = &crtc->properties;
 
-	list_add_tail(&crtc->head, &dev->mode_config.crtc_list);
-	dev->mode_config.num_crtc++;
+	list_add_tail(&crtc->head, &config->crtc_list);
+	config->num_crtc++;
 
 	crtc->primary = primary;
 	if (primary)

@@ -754,6 +792,8 @@ void drm_crtc_cleanup(struct drm_crtc *crtc)
 	kfree(crtc->gamma_store);
 	crtc->gamma_store = NULL;
 
+	drm_modeset_lock_fini(&crtc->mutex);
+
 	drm_mode_object_put(dev, &crtc->base);
 	list_del(&crtc->head);
 	dev->mode_config.num_crtc--;

@@ -1817,7 +1857,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 	DRM_DEBUG_KMS("[CONNECTOR:%d:?]\n", out_resp->connector_id);
 
 	mutex_lock(&dev->mode_config.mutex);
-	mutex_lock(&dev->mode_config.connection_mutex);
+	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 
 	connector = drm_connector_find(dev, out_resp->connector_id);
 	if (!connector) {

@@ -1916,7 +1956,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 	out_resp->count_encoders = encoders_count;
 
 out:
-	mutex_unlock(&dev->mode_config.connection_mutex);
+	drm_modeset_unlock(&dev->mode_config.connection_mutex);
 	mutex_unlock(&dev->mode_config.mutex);
 
 	return ret;

@@ -2500,7 +2540,7 @@ static int drm_mode_cursor_common(struct drm_device *dev,
 		return -ENOENT;
 	}
 
-	mutex_lock(&crtc->mutex);
+	drm_modeset_lock(&crtc->mutex, NULL);
 	if (req->flags & DRM_MODE_CURSOR_BO) {
 		if (!crtc->funcs->cursor_set && !crtc->funcs->cursor_set2) {
 			ret = -ENXIO;

@@ -2524,7 +2564,7 @@ static int drm_mode_cursor_common(struct drm_device *dev,
 		}
 	}
 out:
-	mutex_unlock(&crtc->mutex);
+	drm_modeset_unlock(&crtc->mutex);
 
 	return ret;
 

@@ -4217,7 +4257,7 @@ int drm_mode_page_flip_ioctl(struct drm_device *dev,
 	if (!crtc)
 		return -ENOENT;
 
-	mutex_lock(&crtc->mutex);
+	drm_modeset_lock(&crtc->mutex, NULL);
 	if (crtc->primary->fb == NULL) {
 		/* The framebuffer is currently unbound, presumably
 		 * due to a hotplug event, that userspace has not

@@ -4301,7 +4341,7 @@ out:
 		drm_framebuffer_unreference(fb);
 	if (old_fb)
 		drm_framebuffer_unreference(old_fb);
-	mutex_unlock(&crtc->mutex);
+	drm_modeset_unlock(&crtc->mutex);
 
 	return ret;
 }

@@ -4666,7 +4706,7 @@ EXPORT_SYMBOL(drm_format_vert_chroma_subsampling);
 void drm_mode_config_init(struct drm_device *dev)
 {
 	mutex_init(&dev->mode_config.mutex);
-	mutex_init(&dev->mode_config.connection_mutex);
+	drm_modeset_lock_init(&dev->mode_config.connection_mutex);
 	mutex_init(&dev->mode_config.idr_mutex);
 	mutex_init(&dev->mode_config.fb_lock);
 	INIT_LIST_HEAD(&dev->mode_config.fb_list);

@@ -4766,5 +4806,6 @@ void drm_mode_config_cleanup(struct drm_device *dev)
 	}
 
 	idr_destroy(&dev->mode_config.crtc_idr);
+	drm_modeset_lock_fini(&dev->mode_config.connection_mutex);
 }
 EXPORT_SYMBOL(drm_mode_config_cleanup);

drivers/gpu/drm/drm_crtc_helper.c +1 -2

index 5b93caf..4eaded8 100644
@@ -89,8 +89,7 @@ bool drm_helper_encoder_in_use(struct drm_encoder *encoder)
 	struct drm_device *dev = encoder->dev;
 
 	WARN_ON(!mutex_is_locked(&dev->mode_config.mutex));
-	WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
-
+	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 		if (connector->encoder == encoder)
 			return true;

drivers/gpu/drm/drm_fb_helper.c +4 -0

index e95ed58..b891f4c 100644
@@ -331,6 +331,10 @@ static bool drm_fb_helper_force_kernel_mode(void)
 		if (dev->switch_power_state == DRM_SWITCH_POWER_OFF)
 			continue;
 
+		/* NOTE: we use lockless flag below to avoid grabbing other
+		 * modeset locks.  So just trylock the underlying mutex
+		 * directly:
+		 */
 		if (!mutex_trylock(&dev->mode_config.mutex)) {
 			error = true;
 			continue;

drivers/gpu/drm/drm_modeset_lock.c new file +179 -0

new file mode 100644
index 0000000..edd8508
@@ -0,0 +1,179 @@
+/*
+ * Copyright (C) 2014 Red Hat
+ * Author: Rob Clark <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <drm/drmP.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_modeset_lock.h>
+
+
+void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx,
+		uint32_t flags)
+{
+	ww_acquire_init(&ctx->ww_ctx, &crtc_ww_class);
+	INIT_LIST_HEAD(&ctx->locked);
+}
+EXPORT_SYMBOL(drm_modeset_acquire_init);
+
+void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx)
+{
+	ww_acquire_fini(&ctx->ww_ctx);
+}
+EXPORT_SYMBOL(drm_modeset_acquire_fini);
+
+void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx)
+{
+	WARN_ON(ctx->contended);
+	while (!list_empty(&ctx->locked)) {
+		struct drm_modeset_lock *lock;
+
+		lock = list_first_entry(&ctx->locked,
+				struct drm_modeset_lock, head);
+
+		drm_modeset_unlock(lock);
+	}
+}
+EXPORT_SYMBOL(drm_modeset_drop_locks);
+
+static inline int modeset_lock(struct drm_modeset_lock *lock,
+		struct drm_modeset_acquire_ctx *ctx,
+		bool interruptible, bool slow)
+{
+	int ret;
+
+	WARN_ON(ctx->contended);
+
+	if (interruptible && slow) {
+		ret = ww_mutex_lock_slow_interruptible(&lock->mutex, &ctx->ww_ctx);
+	} else if (interruptible) {
+		ret = ww_mutex_lock_interruptible(&lock->mutex, &ctx->ww_ctx);
+	} else if (slow) {
+		ww_mutex_lock_slow(&lock->mutex, &ctx->ww_ctx);
+		ret = 0;
+	} else {
+		ret = ww_mutex_lock(&lock->mutex, &ctx->ww_ctx);
+	}
+	if (!ret) {
+		WARN_ON(!list_empty(&lock->head));
+		list_add(&lock->head, &ctx->locked);
+	} else if (ret == -EALREADY) {
+		/* we already hold the lock.. this is fine.  For atomic
+		 * we will need to be able to drm_modeset_lock() things
+		 * without having to keep track of what is already locked
+		 * or not.
+		 */
+		ret = 0;
+	} else if (ret == -EDEADLK) {
+		ctx->contended = lock;
+	}
+
+	return ret;
+}
+
+static int modeset_backoff(struct drm_modeset_acquire_ctx *ctx,
+		bool interruptible)
+{
+	struct drm_modeset_lock *contended = ctx->contended;
+
+	ctx->contended = NULL;
+
+	if (WARN_ON(!contended))
+		return 0;
+
+	drm_modeset_drop_locks(ctx);
+
+	return modeset_lock(contended, ctx, interruptible, true);
+}
+
+void drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx)
+{
+	modeset_backoff(ctx, false);
+}
+EXPORT_SYMBOL(drm_modeset_backoff);
+
+int drm_modeset_backoff_interruptable(struct drm_modeset_acquire_ctx *ctx)
+{
+	return modeset_backoff(ctx, true);
+}
+EXPORT_SYMBOL(drm_modeset_backoff_interruptable);
+
+/**
+ * drm_modeset_lock - take modeset lock
+ * @lock: lock to take
+ * @ctx: acquire ctx
+ *
+ * If ctx is not NULL, then then it's acquire context is used
+ * and the lock does not need to be explicitly unlocked, it
+ * will be automatically unlocked when the atomic update is
+ * complete
+ */
+int drm_modeset_lock(struct drm_modeset_lock *lock,
+		struct drm_modeset_acquire_ctx *ctx)
+{
+	if (ctx)
+		return modeset_lock(lock, ctx, false, false);
+
+	ww_mutex_lock(&lock->mutex, NULL);
+	return 0;
+}
+EXPORT_SYMBOL(drm_modeset_lock);
+
+int drm_modeset_lock_interruptible(struct drm_modeset_lock *lock,
+		struct drm_modeset_acquire_ctx *ctx)
+{
+	if (ctx)
+		return modeset_lock(lock, ctx, true, false);
+
+	return ww_mutex_lock_interruptible(&lock->mutex, NULL);
+}
+EXPORT_SYMBOL(drm_modeset_lock_interruptible);
+
+/**
+ * drm_modeset_unlock - drop modeset lock
+ * @lock: lock to release
+ */
+void drm_modeset_unlock(struct drm_modeset_lock *lock)
+{
+	list_del_init(&lock->head);
+	ww_mutex_unlock(&lock->mutex);
+}
+EXPORT_SYMBOL(drm_modeset_unlock);
+
+/**
+ * drm_modeset_lock_all_crtcs - helper to drm_modeset_lock() all CRTCs
+ */
+int drm_modeset_lock_all_crtcs(struct drm_device *dev,
+		struct drm_modeset_acquire_ctx *ctx)
+{
+	struct drm_mode_config *config = &dev->mode_config;
+	struct drm_crtc *crtc;
+	int ret = 0;
+
+	list_for_each_entry(crtc, &config->crtc_list, head) {
+		ret = drm_modeset_lock(&crtc->mutex, ctx);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_modeset_lock_all_crtcs);

drivers/gpu/drm/drm_plane_helper.c +1 -1

index 458d9bf..6301ec6 100644
@@ -59,7 +59,7 @@ static int get_connectors_for_crtc(struct drm_crtc *crtc,
 	 * need to grab the connection_mutex here to be able to make these
 	 * checks.
 	 */
-	WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
+	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
 	list_for_each_entry(connector, &dev->mode_config.connector_list, head)
 		if (connector->encoder && connector->encoder->crtc == crtc) {

drivers/gpu/drm/i915/intel_crt.c +3 -2

index 22d8347..33328fc 100644
@@ -630,6 +630,7 @@ intel_crt_detect(struct drm_connector *connector, bool force)
 	enum intel_display_power_domain power_domain;
 	enum drm_connector_status status;
 	struct intel_load_detect_pipe tmp;
+	struct drm_modeset_acquire_ctx ctx;
 
 	intel_runtime_pm_get(dev_priv);
 

@@ -673,12 +674,12 @@ intel_crt_detect(struct drm_connector *connector, bool force)
 	}
 
 	/* for pre-945g platforms use load detect */
-	if (intel_get_load_detect_pipe(connector, NULL, &tmp)) {
+	if (intel_get_load_detect_pipe(connector, NULL, &tmp, &ctx)) {
 		if (intel_crt_detect_ddc(connector))
 			status = connector_status_connected;
 		else
 			status = intel_crt_load_detect(crt);
-		intel_release_load_detect_pipe(connector, &tmp);
+		intel_release_load_detect_pipe(connector, &tmp, &ctx);
 	} else
 		status = connector_status_unknown;
 

drivers/gpu/drm/i915/intel_display.c +38 -20

index 8cf4bde..f5a49f8 100644
@@ -2363,7 +2363,7 @@ void intel_display_handle_reset(struct drm_device *dev)
 	list_for_each_entry(crtc, &dev->mode_config.crtc_list, head) {
 		struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 
-		mutex_lock(&crtc->mutex);
+		drm_modeset_lock(&crtc->mutex, NULL);
 		/*
 		 * FIXME: Once we have proper support for primary planes (and
 		 * disabling them without disabling the entire crtc) allow again

@@ -2374,7 +2374,7 @@ void intel_display_handle_reset(struct drm_device *dev)
 							       crtc->primary->fb,
 							       crtc->x,
 							       crtc->y);
-		mutex_unlock(&crtc->mutex);
+		drm_modeset_unlock(&crtc->mutex);
 	}
 }
 

@@ -7972,7 +7972,8 @@ mode_fits_in_fbdev(struct drm_device *dev,
 
 bool intel_get_load_detect_pipe(struct drm_connector *connector,
 				struct drm_display_mode *mode,
-				struct intel_load_detect_pipe *old)
+				struct intel_load_detect_pipe *old,
+				struct drm_modeset_acquire_ctx *ctx)
 {
 	struct intel_crtc *intel_crtc;
 	struct intel_encoder *intel_encoder =

@@ -7982,13 +7983,19 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
 	struct drm_crtc *crtc = NULL;
 	struct drm_device *dev = encoder->dev;
 	struct drm_framebuffer *fb;
-	int i = -1;
+	struct drm_mode_config *config = &dev->mode_config;
+	int ret, i = -1;
 
 	DRM_DEBUG_KMS("[CONNECTOR:%d:%s], [ENCODER:%d:%s]\n",
 		      connector->base.id, drm_get_connector_name(connector),
 		      encoder->base.id, drm_get_encoder_name(encoder));
 
-	mutex_lock(&dev->mode_config.connection_mutex);
+	drm_modeset_acquire_init(ctx, 0);
+
+retry:
+	ret = drm_modeset_lock(&config->connection_mutex, ctx);
+	if (ret)
+		goto fail_unlock;
 
 	/*
 	 * Algorithm gets a little messy:

@@ -8004,7 +8011,9 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
 	if (encoder->crtc) {
 		crtc = encoder->crtc;
 
-		mutex_lock(&crtc->mutex);
+		ret = drm_modeset_lock(&crtc->mutex, ctx);
+		if (ret)
+			goto fail_unlock;
 
 		old->dpms_mode = connector->dpms;
 		old->load_detect_temp = false;

@@ -8017,7 +8026,7 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
 	}
 
 	/* Find an unused one (if possible) */
-	list_for_each_entry(possible_crtc, &dev->mode_config.crtc_list, head) {
+	list_for_each_entry(possible_crtc, &config->crtc_list, head) {
 		i++;
 		if (!(encoder->possible_crtcs & (1 << i)))
 			continue;

@@ -8032,10 +8041,12 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
 	 */
 	if (!crtc) {
 		DRM_DEBUG_KMS("no pipe available for load-detect\n");
-		goto fail_unlock_connector;
+		goto fail_unlock;
 	}
 
-	mutex_lock(&crtc->mutex);
+	ret = drm_modeset_lock(&crtc->mutex, ctx);
+	if (ret)
+		goto fail_unlock;
 	intel_encoder->new_crtc = to_intel_crtc(crtc);
 	to_intel_connector(connector)->new_encoder = intel_encoder;
 

@@ -8085,15 +8096,21 @@ bool intel_get_load_detect_pipe(struct drm_connector *connector,
 		intel_crtc->new_config = &intel_crtc->config;
 	else
 		intel_crtc->new_config = NULL;
-	mutex_unlock(&crtc->mutex);
-fail_unlock_connector:
-	mutex_unlock(&dev->mode_config.connection_mutex);
+fail_unlock:
+	if (ret == -EDEADLK) {
+		drm_modeset_backoff(ctx);
+		goto retry;
+	}
+
+	drm_modeset_drop_locks(ctx);
+	drm_modeset_acquire_fini(ctx);
 
 	return false;
 }
 
 void intel_release_load_detect_pipe(struct drm_connector *connector,
-				    struct intel_load_detect_pipe *old)
+				    struct intel_load_detect_pipe *old,
+				    struct drm_modeset_acquire_ctx *ctx)
 {
 	struct intel_encoder *intel_encoder =
 		intel_attached_encoder(connector);

@@ -8117,8 +8134,7 @@ void intel_release_load_detect_pipe(struct drm_connector *connector,
 			drm_framebuffer_unreference(old->release_fb);
 		}
 
-		mutex_unlock(&crtc->mutex);
-		mutex_unlock(&connector->dev->mode_config.connection_mutex);
+		goto unlock;
 		return;
 	}
 

@@ -8126,8 +8142,9 @@ void intel_release_load_detect_pipe(struct drm_connector *connector,
 	if (old->dpms_mode != DRM_MODE_DPMS_ON)
 		connector->funcs->dpms(connector, old->dpms_mode);
 
-	mutex_unlock(&crtc->mutex);
-	mutex_unlock(&connector->dev->mode_config.connection_mutex);
+unlock:
+	drm_modeset_drop_locks(ctx);
+	drm_modeset_acquire_fini(ctx);
 }
 
 static int i9xx_pll_refclk(struct drm_device *dev,

@@ -10586,7 +10603,7 @@ enum pipe intel_get_pipe_from_connector(struct intel_connector *connector)
 	struct drm_encoder *encoder = connector->base.encoder;
 	struct drm_device *dev = connector->base.dev;
 
-	WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
+	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
 	if (!encoder)
 		return INVALID_PIPE;

@@ -11386,6 +11403,7 @@ static void intel_enable_pipe_a(struct drm_device *dev)
 	struct intel_connector *connector;
 	struct drm_connector *crt = NULL;
 	struct intel_load_detect_pipe load_detect_temp;
+	struct drm_modeset_acquire_ctx ctx;
 
 	/* We can't just switch on the pipe A, we need to set things up with a
 	 * proper mode and output configuration. As a gross hack, enable pipe A

@@ -11402,8 +11420,8 @@ static void intel_enable_pipe_a(struct drm_device *dev)
 	if (!crt)
 		return;
 
-	if (intel_get_load_detect_pipe(crt, NULL, &load_detect_temp))
-		intel_release_load_detect_pipe(crt, &load_detect_temp);
+	if (intel_get_load_detect_pipe(crt, NULL, &load_detect_temp, &ctx))
+		intel_release_load_detect_pipe(crt, &load_detect_temp, &ctx);
 
 
 }

drivers/gpu/drm/i915/intel_dp.c +7 -7

index 89fd1dd..9926dc1 100644
@@ -1131,7 +1131,7 @@ static void edp_panel_vdd_off_sync(struct intel_dp *intel_dp)
 	u32 pp;
 	u32 pp_stat_reg, pp_ctrl_reg;
 
-	WARN_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
+	WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
 	if (!intel_dp->want_panel_vdd && edp_have_panel_vdd(intel_dp)) {
 		struct intel_digital_port *intel_dig_port =

@@ -1168,9 +1168,9 @@ static void edp_panel_vdd_work(struct work_struct *__work)
 						 struct intel_dp, panel_vdd_work);
 	struct drm_device *dev = intel_dp_to_dev(intel_dp);
 
-	mutex_lock(&dev->mode_config.connection_mutex);
+	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 	edp_panel_vdd_off_sync(intel_dp);
-	mutex_unlock(&dev->mode_config.connection_mutex);
+	drm_modeset_unlock(&dev->mode_config.connection_mutex);
 }
 
 static void edp_panel_vdd_off(struct intel_dp *intel_dp, bool sync)

@@ -3384,9 +3384,9 @@ void intel_dp_encoder_destroy(struct drm_encoder *encoder)
 	drm_encoder_cleanup(encoder);
 	if (is_edp(intel_dp)) {
 		cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
-		mutex_lock(&dev->mode_config.connection_mutex);
+		drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 		edp_panel_vdd_off_sync(intel_dp);
-		mutex_unlock(&dev->mode_config.connection_mutex);
+		drm_modeset_unlock(&dev->mode_config.connection_mutex);
 	}
 	kfree(intel_dig_port);
 }

@@ -3965,9 +3965,9 @@ intel_dp_init_connector(struct intel_digital_port *intel_dig_port,
 		drm_dp_aux_unregister_i2c_bus(&intel_dp->aux);
 		if (is_edp(intel_dp)) {
 			cancel_delayed_work_sync(&intel_dp->panel_vdd_work);
-			mutex_lock(&dev->mode_config.connection_mutex);
+			drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 			edp_panel_vdd_off_sync(intel_dp);
-			mutex_unlock(&dev->mode_config.connection_mutex);
+			drm_modeset_unlock(&dev->mode_config.connection_mutex);
 		}
 		drm_sysfs_connector_remove(connector);
 		drm_connector_cleanup(connector);

drivers/gpu/drm/i915/intel_drv.h +4 -2

index d8b540b..824f8ae 100644
@@ -721,9 +721,11 @@ void vlv_wait_port_ready(struct drm_i915_private *dev_priv,
 			 struct intel_digital_port *dport);
 bool intel_get_load_detect_pipe(struct drm_connector *connector,
 				struct drm_display_mode *mode,
-				struct intel_load_detect_pipe *old);
+				struct intel_load_detect_pipe *old,
+				struct drm_modeset_acquire_ctx *ctx);
 void intel_release_load_detect_pipe(struct drm_connector *connector,
-				    struct intel_load_detect_pipe *old);
+				    struct intel_load_detect_pipe *old,
+				    struct drm_modeset_acquire_ctx *ctx);
 int intel_pin_and_fence_fb_obj(struct drm_device *dev,
 			       struct drm_i915_gem_object *obj,
 			       struct intel_ring_buffer *pipelined);

drivers/gpu/drm/i915/intel_opregion.c +2 -2

index b812e9d..2e2c71f 100644
@@ -410,7 +410,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 	if (bclp > 255)
 		return ASLC_BACKLIGHT_FAILED;
 
-	mutex_lock(&dev->mode_config.connection_mutex);
+	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 
 	/*
 	 * Update backlight on all connectors that support backlight (usually

@@ -421,7 +421,7 @@ static u32 asle_set_backlight(struct drm_device *dev, u32 bclp)
 		intel_panel_set_backlight(intel_connector, bclp, 255);
 	iowrite32(DIV_ROUND_UP(bclp * 100, 255) | ASLE_CBLV_VALID, &asle->cblv);
 
-	mutex_unlock(&dev->mode_config.connection_mutex);
+	drm_modeset_unlock(&dev->mode_config.connection_mutex);
 
 
 	return 0;

drivers/gpu/drm/i915/intel_overlay.c +2 -2

index 88249c4..961164d 100644
@@ -688,7 +688,7 @@ static int intel_overlay_do_put_image(struct intel_overlay *overlay,
 	u32 swidth, swidthsw, sheight, ostride;
 
 	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
-	BUG_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
+	BUG_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 	BUG_ON(!overlay);
 
 	ret = intel_overlay_release_old_vid(overlay);

@@ -793,7 +793,7 @@ int intel_overlay_switch_off(struct intel_overlay *overlay)
 	int ret;
 
 	BUG_ON(!mutex_is_locked(&dev->struct_mutex));
-	BUG_ON(!mutex_is_locked(&dev->mode_config.connection_mutex));
+	BUG_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
 
 	ret = intel_overlay_recover_from_interrupt(overlay);
 	if (ret != 0)

drivers/gpu/drm/i915/intel_panel.c +4 -4

index f3df527..f45d874 100644
@@ -823,12 +823,12 @@ static int intel_backlight_device_update_status(struct backlight_device *bd)
 	struct intel_connector *connector = bl_get_data(bd);
 	struct drm_device *dev = connector->base.dev;
 
-	mutex_lock(&dev->mode_config.connection_mutex);
+	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 	DRM_DEBUG_KMS("updating intel_backlight, brightness=%d/%d\n",
 		      bd->props.brightness, bd->props.max_brightness);
 	intel_panel_set_backlight(connector, bd->props.brightness,
 				  bd->props.max_brightness);
-	mutex_unlock(&dev->mode_config.connection_mutex);
+	drm_modeset_unlock(&dev->mode_config.connection_mutex);
 	return 0;
 }
 

@@ -840,9 +840,9 @@ static int intel_backlight_device_get_brightness(struct backlight_device *bd)
 	int ret;
 
 	intel_runtime_pm_get(dev_priv);
-	mutex_lock(&dev->mode_config.connection_mutex);
+	drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
 	ret = intel_panel_get_backlight(connector);
-	mutex_unlock(&dev->mode_config.connection_mutex);
+	drm_modeset_unlock(&dev->mode_config.connection_mutex);
 	intel_runtime_pm_put(dev_priv);
 
 	return ret;

drivers/gpu/drm/i915/intel_sprite.c +1 -1

index 213cd58..c235546 100644
@@ -55,7 +55,7 @@ static bool intel_pipe_update_start(struct intel_crtc *crtc, uint32_t *start_vbl
 	int scanline, min, max, vblank_start;
 	DEFINE_WAIT(wait);
 
-	WARN_ON(!mutex_is_locked(&crtc->base.mutex));
+	WARN_ON(!drm_modeset_is_locked(&crtc->base.mutex));
 
 	vblank_start = mode->crtc_vblank_start;
 	if (mode->flags & DRM_MODE_FLAG_INTERLACE)

drivers/gpu/drm/i915/intel_tv.c +3 -2

index e0193e8..97d9fc9 100644
@@ -1321,10 +1321,11 @@ intel_tv_detect(struct drm_connector *connector, bool force)
 
 	if (force) {
 		struct intel_load_detect_pipe tmp;
+		struct drm_modeset_acquire_ctx ctx;
 
-		if (intel_get_load_detect_pipe(connector, &mode, &tmp)) {
+		if (intel_get_load_detect_pipe(connector, &mode, &tmp, &ctx)) {
 			type = intel_tv_detect_type(intel_tv, connector);
-			intel_release_load_detect_pipe(connector, &tmp);
+			intel_release_load_detect_pipe(connector, &tmp, &ctx);
 		} else
 			return connector_status_unknown;
 	} else

drivers/gpu/drm/omapdrm/omap_crtc.c +5 -5

index e3c47a8..2d28dc3 100644
@@ -319,13 +319,13 @@ static void page_flip_worker(struct work_struct *work)
 	struct drm_display_mode *mode = &crtc->mode;
 	struct drm_gem_object *bo;
 
-	mutex_lock(&crtc->mutex);
+	drm_modeset_lock(&crtc->mutex, NULL);
 	omap_plane_mode_set(omap_crtc->plane, crtc, crtc->primary->fb,
 			0, 0, mode->hdisplay, mode->vdisplay,
 			crtc->x << 16, crtc->y << 16,
 			mode->hdisplay << 16, mode->vdisplay << 16,
 			vblank_cb, crtc);
-	mutex_unlock(&crtc->mutex);
+	drm_modeset_unlock(&crtc->mutex);
 
 	bo = omap_framebuffer_bo(crtc->primary->fb, 0);
 	drm_gem_object_unreference_unlocked(bo);

@@ -465,7 +465,7 @@ static void apply_worker(struct work_struct *work)
 	 * the callbacks and list modification all serialized
 	 * with respect to modesetting ioctls from userspace.
 	 */
-	mutex_lock(&crtc->mutex);
+	drm_modeset_lock(&crtc->mutex, NULL);
 	dispc_runtime_get();
 
 	/*

@@ -510,7 +510,7 @@ static void apply_worker(struct work_struct *work)
 
 out:
 	dispc_runtime_put();
-	mutex_unlock(&crtc->mutex);
+	drm_modeset_unlock(&crtc->mutex);
 }
 
 int omap_crtc_apply(struct drm_crtc *crtc,

@@ -518,7 +518,7 @@ int omap_crtc_apply(struct drm_crtc *crtc,
 {
 	struct omap_crtc *omap_crtc = to_omap_crtc(crtc);
 
-	WARN_ON(!mutex_is_locked(&crtc->mutex));
+	WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
 
 	/* no need to queue it again if it is already queued: */
 	if (apply->queued)

drivers/gpu/drm/vmwgfx/vmwgfx_kms.c +4 -4

index e7199b4..8f3edc4 100644
@@ -187,7 +187,7 @@ int vmw_du_crtc_cursor_set(struct drm_crtc *crtc, struct drm_file *file_priv,
 	 * can do this since the caller in the drm core doesn't check anything
 	 * which is protected by any looks.
 	 */
-	mutex_unlock(&crtc->mutex);
+	drm_modeset_unlock(&crtc->mutex);
 	drm_modeset_lock_all(dev_priv->dev);
 
 	/* A lot of the code assumes this */

@@ -252,7 +252,7 @@ int vmw_du_crtc_cursor_set(struct drm_crtc *crtc, struct drm_file *file_priv,
 	ret = 0;
 out:
 	drm_modeset_unlock_all(dev_priv->dev);
-	mutex_lock(&crtc->mutex);
+	drm_modeset_lock(&crtc->mutex, NULL);
 
 	return ret;
 }

@@ -273,7 +273,7 @@ int vmw_du_crtc_cursor_move(struct drm_crtc *crtc, int x, int y)
 	 * can do this since the caller in the drm core doesn't check anything
 	 * which is protected by any looks.
 	 */
-	mutex_unlock(&crtc->mutex);
+	drm_modeset_unlock(&crtc->mutex);
 	drm_modeset_lock_all(dev_priv->dev);
 
 	vmw_cursor_update_position(dev_priv, shown,

@@ -281,7 +281,7 @@ int vmw_du_crtc_cursor_move(struct drm_crtc *crtc, int x, int y)
 				   du->cursor_y + du->hotspot_y);
 
 	drm_modeset_unlock_all(dev_priv->dev);
-	mutex_lock(&crtc->mutex);
+	drm_modeset_lock(&crtc->mutex, NULL);
 
 	return 0;
 }

include/drm/drmP.h +0 -5

index 12f10bc..a9b8a5d 100644
@@ -1184,11 +1184,6 @@ static inline int drm_device_is_unplugged(struct drm_device *dev)
 	return ret;
 }
 
-static inline bool drm_modeset_is_locked(struct drm_device *dev)
-{
-	return mutex_is_locked(&dev->mode_config.mutex);
-}
-
 static inline bool drm_is_render_client(const struct drm_file *file_priv)
 {
 	return file_priv->minor->type == DRM_MINOR_RENDER;

include/drm/drm_crtc.h +9 -6

index 56dffc6..3a3f7da 100644
@@ -33,6 +33,7 @@
 #include <linux/hdmi.h>
 #include <drm/drm_mode.h>
 #include <drm/drm_fourcc.h>
+#include <drm/drm_modeset_lock.h>
 
 struct drm_device;
 struct drm_mode_set;

@@ -205,6 +206,10 @@ struct drm_property {
 	struct list_head enum_blob_list;
 };
 
+void drm_modeset_lock_all(struct drm_device *dev);
+void drm_modeset_unlock_all(struct drm_device *dev);
+void drm_warn_on_modeset_not_all_locked(struct drm_device *dev);
+
 struct drm_crtc;
 struct drm_connector;
 struct drm_encoder;

@@ -280,6 +285,7 @@ struct drm_crtc_funcs {
  * drm_crtc - central CRTC control structure
  * @dev: parent DRM device
  * @head: list management
+ * @mutex: per-CRTC locking
  * @base: base KMS object for ID tracking etc.
  * @primary: primary plane for this CRTC
  * @cursor: cursor plane for this CRTC

@@ -314,7 +320,7 @@ struct drm_crtc {
 	 * state, ...) and a write lock for everything which can be update
 	 * without a full modeset (fb, cursor data, ...)
 	 */
-	struct mutex mutex;
+	struct drm_modeset_lock mutex;
 
 	struct drm_mode_object base;
 

@@ -738,7 +744,8 @@ struct drm_mode_group {
  */
 struct drm_mode_config {
 	struct mutex mutex; /* protects configuration (mode lists etc.) */
-	struct mutex connection_mutex; /* protects connector->encoder and encoder->crtc links */
+	struct drm_modeset_lock connection_mutex; /* protects connector->encoder and encoder->crtc links */
+	struct drm_modeset_acquire_ctx *acquire_ctx; /* for legacy _lock_all() / _unlock_all() */
 	struct mutex idr_mutex; /* for IDR management */
 	struct idr crtc_idr; /* use this idr for all IDs, fb, crtc, connector, modes - just makes life easier */
 	/* this is limited to one for now */

@@ -839,10 +846,6 @@ struct drm_prop_enum_list {
 	char *name;
 };
 
-extern void drm_modeset_lock_all(struct drm_device *dev);
-extern void drm_modeset_unlock_all(struct drm_device *dev);
-extern void drm_warn_on_modeset_not_all_locked(struct drm_device *dev);
-
 extern int drm_crtc_init_with_planes(struct drm_device *dev,
 				     struct drm_crtc *crtc,
 				     struct drm_plane *primary,

include/drm/drm_modeset_lock.h new file +103 -0

new file mode 100644
index 0000000..cfb1dc1
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2014 Red Hat
+ * Author: Rob Clark <[email protected]>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef DRM_MODESET_LOCK_H_
+#define DRM_MODESET_LOCK_H_
+
+#include <linux/ww_mutex.h>
+
+struct drm_modeset_lock;
+
+struct drm_modeset_acquire_ctx {
+
+	struct ww_acquire_ctx ww_ctx;
+
+	/* contended lock: if a lock is contended you should only call
+	 * drm_modeset_backoff() which drops locks and slow-locks the
+	 * contended lock.
+	 */
+	struct drm_modeset_lock *contended;
+
+	/* list of 'struct drm_modeset_lock': */
+	struct list_head locked;
+};
+
+/**
+ * drm_modeset_lock - used for locking modeset resources.
+ * @mutex: resource locking
+ * @atomic_pending: is this resource part of a still-pending
+ *    atomic update
+ * @head: used to hold it's place on state->locked list when
+ *    part of an atomic update
+ *
+ * Used for locking CRTCs and other modeset resources.
+ */
+struct drm_modeset_lock {
+	/**
+	 * modeset lock
+	 */
+	struct ww_mutex mutex;
+
+	/**
+	 * Resources that are locked as part of an atomic update are added
+	 * to a list (so we know what to unlock at the end).
+	 */
+	struct list_head head;
+};
+
+extern struct ww_class crtc_ww_class;
+
+void drm_modeset_acquire_init(struct drm_modeset_acquire_ctx *ctx,
+		uint32_t flags);
+void drm_modeset_acquire_fini(struct drm_modeset_acquire_ctx *ctx);
+void drm_modeset_drop_locks(struct drm_modeset_acquire_ctx *ctx);
+void drm_modeset_backoff(struct drm_modeset_acquire_ctx *ctx);
+int drm_modeset_backoff_interruptable(struct drm_modeset_acquire_ctx *ctx);
+
+static inline void drm_modeset_lock_init(struct drm_modeset_lock *lock)
+{
+	ww_mutex_init(&lock->mutex, &crtc_ww_class);
+	INIT_LIST_HEAD(&lock->head);
+}
+
+static inline void drm_modeset_lock_fini(struct drm_modeset_lock *lock)
+{
+	WARN_ON(!list_empty(&lock->head));
+}
+
+static inline bool drm_modeset_is_locked(struct drm_modeset_lock *lock)
+{
+	return ww_mutex_is_locked(&lock->mutex);
+}
+
+int drm_modeset_lock(struct drm_modeset_lock *lock,
+		struct drm_modeset_acquire_ctx *ctx);
+int drm_modeset_lock_interruptible(struct drm_modeset_lock *lock,
+		struct drm_modeset_acquire_ctx *ctx);
+void drm_modeset_unlock(struct drm_modeset_lock *lock);
+
+struct drm_device;
+int drm_modeset_lock_all_crtcs(struct drm_device *dev,
+		struct drm_modeset_acquire_ctx *ctx);
+
+#endif /* DRM_MODESET_LOCK_H_ */

Signature · 1 line

1.9.3

Quoted 15 lines · Rob Clark

For atomic, it will be quite necessary to not need to care so much about locking order. And 'state' gives us a convenient place to stash a ww_ctx for any sort of update that needs to grab multiple crtc locks.

Because we will want to eventually make locking even more fine grained (giving locks to planes, connectors, etc), split out drm_modeset_lock and drm_modeset_acquire_ctx to track acquired locks.

Atomic will use this to keep track of which locks have been acquired in a transaction.

v1: original
v2: remove a few things not needed until atomic, for now
v3: update for v3 of connection_mutex patch..

Quoted 1 line

Signed-off-by Rob Clark <[email protected]>

Still meh about the lock_all_crtcs helper, imo that one should die. But one todo you've missed from my fixup patch is to add kerneldoc for all the locking helpers (maybe that convinces you to inline lock_all_crtcs ;-) and pull it into the drm docbook template. Otherwise nothing stuck out any more.

Quoted 16 lines · Daniel Vetter

Quoted 15 lines · Rob Clark

For atomic, it will be quite necessary to not need to care so much about locking order. And 'state' gives us a convenient place to stash a ww_ctx for any sort of update that needs to grab multiple crtc locks.

Because we will want to eventually make locking even more fine grained (giving locks to planes, connectors, etc), split out drm_modeset_lock and drm_modeset_acquire_ctx to track acquired locks.

Atomic will use this to keep track of which locks have been acquired in a transaction.

v1: original
v2: remove a few things not needed until atomic, for now
v3: update for v3 of connection_mutex patch..

Quoted 7 lines

Quoted 1 line

Signed-off-by Rob Clark <[email protected]>

Still meh about the lock_all_crtcs helper, imo that one should die. But one todo you've missed from my fixup patch is to add kerneldoc for all the locking helpers (maybe that convinces you to inline lock_all_crtcs ;-) and pull it into the drm docbook template. Otherwise nothing stuck out any more.

I'm happy to apply this one if we get some kerneldoc into it.

I've applied the previous patches to drm-next, there was one conflict in i915, but I think I fixed it up okay, f7ef3fa77fa85b3a8a15b464efd56d0314a3231c was what it was conflicting with.