backend/drm: track pending atomic state in wlr_drm_connector_state

This centralizes logic common for both the atomic and libliftoff
backends. Additionally, a struct will make it easier to implement
multi-connector commits (since it can be stored in an array).

backend/drm/atomic.c

@@ -101,7 +101,7 @@ static void atomic_add(struct atomic *atom, uint32_t id, uint32_t prop, uint64_t
 	}
 }
 
-bool create_mode_blob(struct wlr_drm_connector *conn,
+static bool create_mode_blob(struct wlr_drm_connector *conn,
 		const struct wlr_drm_connector_state *state, uint32_t *blob_id) {
 	if (!state->active) {
 		*blob_id = 0;
@@ -117,7 +117,7 @@ bool create_mode_blob(struct wlr_drm_connector *conn,
 	return true;
 }
 
-bool create_gamma_lut_blob(struct wlr_drm_backend *drm,
+static bool create_gamma_lut_blob(struct wlr_drm_backend *drm,
 		size_t size, const uint16_t *lut, uint32_t *blob_id) {
 	if (size == 0) {
 		*blob_id = 0;
@@ -233,51 +233,12 @@ static void rollback_blob(struct wlr_drm_backend *drm,
 	destroy_blob(drm, next);
 }
 
-static void plane_disable(struct atomic *atom, struct wlr_drm_plane *plane) {
-	uint32_t id = plane->id;
-	const union wlr_drm_plane_props *props = &plane->props;
-	atomic_add(atom, id, props->fb_id, 0);
-	atomic_add(atom, id, props->crtc_id, 0);
-}
-
-static void set_plane_props(struct atomic *atom, struct wlr_drm_backend *drm,
-		struct wlr_drm_plane *plane, struct wlr_drm_fb *fb, uint32_t crtc_id,
-		int32_t x, int32_t y) {
-	uint32_t id = plane->id;
-	const union wlr_drm_plane_props *props = &plane->props;
-
-	if (fb == NULL) {
-		wlr_log(WLR_ERROR, "Failed to acquire FB for plane %"PRIu32, plane->id);
-		atom->failed = true;
-		return;
-	}
-
-	uint32_t width = fb->wlr_buf->width;
-	uint32_t height = fb->wlr_buf->height;
-
-	// The src_* properties are in 16.16 fixed point
-	atomic_add(atom, id, props->src_x, 0);
-	atomic_add(atom, id, props->src_y, 0);
-	atomic_add(atom, id, props->src_w, (uint64_t)width << 16);
-	atomic_add(atom, id, props->src_h, (uint64_t)height << 16);
-	atomic_add(atom, id, props->crtc_w, width);
-	atomic_add(atom, id, props->crtc_h, height);
-	atomic_add(atom, id, props->fb_id, fb->id);
-	atomic_add(atom, id, props->crtc_id, crtc_id);
-	atomic_add(atom, id, props->crtc_x, (uint64_t)x);
-	atomic_add(atom, id, props->crtc_y, (uint64_t)y);
-}
-
-static bool atomic_crtc_commit(struct wlr_drm_connector *conn,
-		const struct wlr_drm_connector_state *state,
-		struct wlr_drm_page_flip *page_flip, uint32_t flags, bool test_only) {
+bool drm_atomic_connector_prepare(struct wlr_drm_connector_state *state, bool modeset) {
+	struct wlr_drm_connector *conn = state->connector;
 	struct wlr_drm_backend *drm = conn->backend;
 	struct wlr_output *output = &conn->output;
 	struct wlr_drm_crtc *crtc = conn->crtc;
 
-	bool modeset = state->modeset;
-	bool active = state->active;
-
 	uint32_t mode_id = crtc->mode_id;
 	if (modeset) {
 		if (!create_mode_blob(conn, state, &mode_id)) {
@@ -321,6 +282,87 @@ static bool atomic_crtc_commit(struct wlr_drm_connector *conn,
 		vrr_enabled = state->base->adaptive_sync_enabled;
 	}
 
+	state->mode_id = mode_id;
+	state->gamma_lut = gamma_lut;
+	state->fb_damage_clips = fb_damage_clips;
+	state->vrr_enabled = vrr_enabled;
+	return true;
+}
+
+void drm_atomic_connector_apply_commit(struct wlr_drm_connector_state *state) {
+	struct wlr_drm_connector *conn = state->connector;
+	struct wlr_drm_crtc *crtc = conn->crtc;
+	struct wlr_drm_backend *drm = conn->backend;
+
+	if (!crtc->own_mode_id) {
+		crtc->mode_id = 0; // don't try to delete previous master's blobs
+	}
+	crtc->own_mode_id = true;
+	commit_blob(drm, &crtc->mode_id, state->mode_id);
+	commit_blob(drm, &crtc->gamma_lut, state->gamma_lut);
+
+	destroy_blob(drm, state->fb_damage_clips);
+}
+
+void drm_atomic_connector_rollback_commit(struct wlr_drm_connector_state *state) {
+	struct wlr_drm_connector *conn = state->connector;
+	struct wlr_drm_crtc *crtc = conn->crtc;
+	struct wlr_drm_backend *drm = conn->backend;
+
+	rollback_blob(drm, &crtc->mode_id, state->mode_id);
+	rollback_blob(drm, &crtc->gamma_lut, state->gamma_lut);
+
+	destroy_blob(drm, state->fb_damage_clips);
+}
+
+static void plane_disable(struct atomic *atom, struct wlr_drm_plane *plane) {
+	uint32_t id = plane->id;
+	const union wlr_drm_plane_props *props = &plane->props;
+	atomic_add(atom, id, props->fb_id, 0);
+	atomic_add(atom, id, props->crtc_id, 0);
+}
+
+static void set_plane_props(struct atomic *atom, struct wlr_drm_backend *drm,
+		struct wlr_drm_plane *plane, struct wlr_drm_fb *fb, uint32_t crtc_id,
+		int32_t x, int32_t y) {
+	uint32_t id = plane->id;
+	const union wlr_drm_plane_props *props = &plane->props;
+
+	if (fb == NULL) {
+		wlr_log(WLR_ERROR, "Failed to acquire FB for plane %"PRIu32, plane->id);
+		atom->failed = true;
+		return;
+	}
+
+	uint32_t width = fb->wlr_buf->width;
+	uint32_t height = fb->wlr_buf->height;
+
+	// The src_* properties are in 16.16 fixed point
+	atomic_add(atom, id, props->src_x, 0);
+	atomic_add(atom, id, props->src_y, 0);
+	atomic_add(atom, id, props->src_w, (uint64_t)width << 16);
+	atomic_add(atom, id, props->src_h, (uint64_t)height << 16);
+	atomic_add(atom, id, props->crtc_w, width);
+	atomic_add(atom, id, props->crtc_h, height);
+	atomic_add(atom, id, props->fb_id, fb->id);
+	atomic_add(atom, id, props->crtc_id, crtc_id);
+	atomic_add(atom, id, props->crtc_x, (uint64_t)x);
+	atomic_add(atom, id, props->crtc_y, (uint64_t)y);
+}
+
+static bool atomic_crtc_commit(struct wlr_drm_connector *conn,
+		struct wlr_drm_connector_state *state,
+		struct wlr_drm_page_flip *page_flip, uint32_t flags, bool test_only) {
+	struct wlr_drm_backend *drm = conn->backend;
+	struct wlr_drm_crtc *crtc = conn->crtc;
+
+	bool modeset = state->modeset;
+	bool active = state->active;
+
+	if (!drm_atomic_connector_prepare(state, modeset)) {
+		return false;
+	}
+
 	if (test_only) {
 		flags |= DRM_MODE_ATOMIC_TEST_ONLY;
 	}
@@ -345,20 +387,20 @@ static bool atomic_crtc_commit(struct wlr_drm_connector *conn,
 	if (modeset && active && conn->props.max_bpc != 0 && conn->max_bpc_bounds[1] != 0) {
 		atomic_add(&atom, conn->id, conn->props.max_bpc, pick_max_bpc(conn, state->primary_fb));
 	}
-	atomic_add(&atom, crtc->id, crtc->props.mode_id, mode_id);
+	atomic_add(&atom, crtc->id, crtc->props.mode_id, state->mode_id);
 	atomic_add(&atom, crtc->id, crtc->props.active, active);
 	if (active) {
 		if (crtc->props.gamma_lut != 0) {
-			atomic_add(&atom, crtc->id, crtc->props.gamma_lut, gamma_lut);
+			atomic_add(&atom, crtc->id, crtc->props.gamma_lut, state->gamma_lut);
 		}
 		if (crtc->props.vrr_enabled != 0) {
-			atomic_add(&atom, crtc->id, crtc->props.vrr_enabled, vrr_enabled);
+			atomic_add(&atom, crtc->id, crtc->props.vrr_enabled, state->vrr_enabled);
 		}
 		set_plane_props(&atom, drm, crtc->primary, state->primary_fb, crtc->id,
 			0, 0);
 		if (crtc->primary->props.fb_damage_clips != 0) {
 			atomic_add(&atom, crtc->primary->id,
-				crtc->primary->props.fb_damage_clips, fb_damage_clips);
+				crtc->primary->props.fb_damage_clips, state->fb_damage_clips);
 		}
 		if (crtc->cursor) {
 			if (drm_connector_is_cursor_visible(conn)) {
@@ -379,17 +421,10 @@ static bool atomic_crtc_commit(struct wlr_drm_connector *conn,
 	atomic_finish(&atom);
 
 	if (ok && !test_only) {
-		if (!crtc->own_mode_id) {
-			crtc->mode_id = 0; // don't try to delete previous master's blobs
-		}
-		crtc->own_mode_id = true;
-		commit_blob(drm, &crtc->mode_id, mode_id);
-		commit_blob(drm, &crtc->gamma_lut, gamma_lut);
+		drm_atomic_connector_apply_commit(state);
 	} else {
-		rollback_blob(drm, &crtc->mode_id, mode_id);
-		rollback_blob(drm, &crtc->gamma_lut, gamma_lut);
+		drm_atomic_connector_rollback_commit(state);
 	}
-	destroy_blob(drm, fb_damage_clips);
 
 	return ok;
 }

backend/drm/drm.c

@@ -489,7 +489,7 @@ static void drm_connector_rollback_commit(const struct wlr_drm_connector_state *
 }
 
 static bool drm_crtc_commit(struct wlr_drm_connector *conn,
-		const struct wlr_drm_connector_state *state,
+		struct wlr_drm_connector_state *state,
 		uint32_t flags, bool test_only) {
 	// Disallow atomic-only flags
 	assert((flags & ~DRM_MODE_PAGE_FLIP_FLAGS) == 0);

backend/drm/legacy.c

@@ -59,7 +59,7 @@ static bool legacy_crtc_test(struct wlr_drm_connector *conn,
 }
 
 static bool legacy_crtc_commit(struct wlr_drm_connector *conn,
-		const struct wlr_drm_connector_state *state,
+		struct wlr_drm_connector_state *state,
 		struct wlr_drm_page_flip *page_flip, uint32_t flags, bool test_only) {
 	if (!legacy_crtc_test(conn, state)) {
 		return false;

backend/drm/libliftoff.c

@@ -126,27 +126,6 @@ static bool add_prop(drmModeAtomicReq *req, uint32_t obj,
 	return true;
 }
 
-static void commit_blob(struct wlr_drm_backend *drm,
-		uint32_t *current, uint32_t next) {
-	if (*current == next) {
-		return;
-	}
-	if (*current != 0) {
-		drmModeDestroyPropertyBlob(drm->fd, *current);
-	}
-	*current = next;
-}
-
-static void rollback_blob(struct wlr_drm_backend *drm,
-		uint32_t *current, uint32_t next) {
-	if (*current == next) {
-		return;
-	}
-	if (next != 0) {
-		drmModeDestroyPropertyBlob(drm->fd, next);
-	}
-}
-
 static bool set_plane_props(struct wlr_drm_plane *plane,
 		struct liftoff_layer *layer, struct wlr_drm_fb *fb, int32_t x, int32_t y, uint64_t zpos) {
 	if (fb == NULL) {
@@ -301,10 +280,9 @@ static void update_layer_feedback(struct wlr_drm_backend *drm,
 }
 
 static bool crtc_commit(struct wlr_drm_connector *conn,
-		const struct wlr_drm_connector_state *state,
+		struct wlr_drm_connector_state *state,
 		struct wlr_drm_page_flip *page_flip, uint32_t flags, bool test_only) {
 	struct wlr_drm_backend *drm = conn->backend;
-	struct wlr_output *output = &conn->output;
 	struct wlr_drm_crtc *crtc = conn->crtc;
 
 	bool modeset = state->modeset;
@@ -314,54 +292,9 @@ static bool crtc_commit(struct wlr_drm_connector *conn,
 		return false;
 	}
 
-	uint32_t mode_id = crtc->mode_id;
-	if (modeset) {
-		if (!create_mode_blob(conn, state, &mode_id)) {
+	if (!drm_atomic_connector_prepare(state, modeset)) {
 		return false;
 	}
-	}
-
-	uint32_t gamma_lut = crtc->gamma_lut;
-	if (state->base->committed & WLR_OUTPUT_STATE_GAMMA_LUT) {
-		// Fallback to legacy gamma interface when gamma properties are not
-		// available (can happen on older Intel GPUs that support gamma but not
-		// degamma).
-		if (crtc->props.gamma_lut == 0) {
-			if (!drm_legacy_crtc_set_gamma(drm, crtc,
-					state->base->gamma_lut_size,
-					state->base->gamma_lut)) {
-				return false;
-			}
-		} else {
-			if (!create_gamma_lut_blob(drm, state->base->gamma_lut_size,
-					state->base->gamma_lut, &gamma_lut)) {
-				return false;
-			}
-		}
-	}
-
-	struct wl_array fb_damage_clips_arr = {0};
-
-	uint32_t primary_fb_damage_clips = 0;
-	if ((state->base->committed & WLR_OUTPUT_STATE_DAMAGE) &&
-			crtc->primary->props.fb_damage_clips != 0) {
-		uint32_t *ptr = wl_array_add(&fb_damage_clips_arr, sizeof(primary_fb_damage_clips));
-		if (ptr == NULL) {
-			return false;
-		}
-		create_fb_damage_clips_blob(drm, state->primary_fb->wlr_buf->width,
-			state->primary_fb->wlr_buf->height, &state->base->damage,
-			&primary_fb_damage_clips);
-		*ptr = primary_fb_damage_clips;
-	}
-
-	bool prev_vrr_enabled =
-		output->adaptive_sync_status == WLR_OUTPUT_ADAPTIVE_SYNC_ENABLED;
-	bool vrr_enabled = prev_vrr_enabled;
-	if ((state->base->committed & WLR_OUTPUT_STATE_ADAPTIVE_SYNC_ENABLED) &&
-			drm_connector_supports_vrr(conn)) {
-		vrr_enabled = state->base->adaptive_sync_enabled;
-	}
 
 	if (test_only) {
 		flags |= DRM_MODE_ATOMIC_TEST_ONLY;
@@ -373,6 +306,7 @@ static bool crtc_commit(struct wlr_drm_connector *conn,
 		flags |= DRM_MODE_ATOMIC_NONBLOCK;
 	}
 
+	struct wl_array fb_damage_clips_arr = {0};
 	drmModeAtomicReq *req = drmModeAtomicAlloc();
 	if (req == NULL) {
 		wlr_log(WLR_ERROR, "drmModeAtomicAlloc failed");
@@ -391,22 +325,22 @@ static bool crtc_commit(struct wlr_drm_connector *conn,
 	}
 	// TODO: set "max bpc"
 	ok = ok &&
-		add_prop(req, crtc->id, crtc->props.mode_id, mode_id) &&
+		add_prop(req, crtc->id, crtc->props.mode_id, state->mode_id) &&
 		add_prop(req, crtc->id, crtc->props.active, active);
 	if (active) {
 		if (crtc->props.gamma_lut != 0) {
-			ok = ok && add_prop(req, crtc->id, crtc->props.gamma_lut, gamma_lut);
+			ok = ok && add_prop(req, crtc->id, crtc->props.gamma_lut, state->gamma_lut);
 		}
 		if (crtc->props.vrr_enabled != 0) {
-			ok = ok && add_prop(req, crtc->id, crtc->props.vrr_enabled, vrr_enabled);
+			ok = ok && add_prop(req, crtc->id, crtc->props.vrr_enabled, state->vrr_enabled);
 		}
 		ok = ok &&
 			set_plane_props(crtc->primary, crtc->primary->liftoff_layer, state->primary_fb, 0, 0, 0) &&
 			set_plane_props(crtc->primary, crtc->liftoff_composition_layer, state->primary_fb, 0, 0, 0);
 		liftoff_layer_set_property(crtc->primary->liftoff_layer,
-			"FB_DAMAGE_CLIPS", primary_fb_damage_clips);
+			"FB_DAMAGE_CLIPS", state->fb_damage_clips);
 		liftoff_layer_set_property(crtc->liftoff_composition_layer,
-			"FB_DAMAGE_CLIPS", primary_fb_damage_clips);
+			"FB_DAMAGE_CLIPS", state->fb_damage_clips);
 
 		if (state->base->committed & WLR_OUTPUT_STATE_LAYERS) {
 			for (size_t i = 0; i < state->base->layers_len; i++) {
@@ -475,15 +409,9 @@ out:
 	drmModeAtomicFree(req);
 
 	if (ok && !test_only) {
-		if (!crtc->own_mode_id) {
-			crtc->mode_id = 0; // don't try to delete previous master's blobs
-		}
-		crtc->own_mode_id = true;
-		commit_blob(drm, &crtc->mode_id, mode_id);
-		commit_blob(drm, &crtc->gamma_lut, gamma_lut);
+		drm_atomic_connector_apply_commit(state);
 	} else {
-		rollback_blob(drm, &crtc->mode_id, mode_id);
-		rollback_blob(drm, &crtc->gamma_lut, gamma_lut);
+		drm_atomic_connector_rollback_commit(state);
 	}
 
 	uint32_t *fb_damage_clips_ptr;

include/backend/drm/drm.h

@@ -131,6 +131,12 @@ struct wlr_drm_connector_state {
 	drmModeModeInfo mode;
 	struct wlr_drm_fb *primary_fb;
 	struct wlr_drm_fb *cursor_fb;
+
+	// used by atomic
+	uint32_t mode_id;
+	uint32_t gamma_lut;
+	uint32_t fb_damage_clips;
+	bool vrr_enabled;
 };
 
 /**

include/backend/drm/iface.h

@@ -20,7 +20,7 @@ struct wlr_drm_interface {
 	void (*finish)(struct wlr_drm_backend *drm);
 	// Commit all pending changes on a CRTC.
 	bool (*crtc_commit)(struct wlr_drm_connector *conn,
-		const struct wlr_drm_connector_state *state,
+		struct wlr_drm_connector_state *state,
 		struct wlr_drm_page_flip *page_flip, uint32_t flags, bool test_only);
 	// Turn off everything
 	bool (*reset)(struct wlr_drm_backend *drm);
@@ -33,12 +33,13 @@ extern const struct wlr_drm_interface liftoff_iface;
 bool drm_legacy_crtc_set_gamma(struct wlr_drm_backend *drm,
 	struct wlr_drm_crtc *crtc, size_t size, uint16_t *lut);
 
-bool create_mode_blob(struct wlr_drm_connector *conn,
-	const struct wlr_drm_connector_state *state, uint32_t *blob_id);
-bool create_gamma_lut_blob(struct wlr_drm_backend *drm,
-	size_t size, const uint16_t *lut, uint32_t *blob_id);
 bool create_fb_damage_clips_blob(struct wlr_drm_backend *drm,
 	int width, int height, const pixman_region32_t *damage, uint32_t *blob_id);
 bool drm_atomic_reset(struct wlr_drm_backend *drm);
 
+bool drm_atomic_connector_prepare(struct wlr_drm_connector_state *state,
+	bool modeset);
+void drm_atomic_connector_apply_commit(struct wlr_drm_connector_state *state);
+void drm_atomic_connector_rollback_commit(struct wlr_drm_connector_state *state);
+
 #endif