xref: /openbmc/linux/drivers/gpu/drm/drm_atomic.c (revision cc8bbe1a)
1 /*
2  * Copyright (C) 2014 Red Hat
3  * Copyright (C) 2014 Intel Corp.
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice shall be included in
13  * all copies or substantial portions of the Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21  * OTHER DEALINGS IN THE SOFTWARE.
22  *
23  * Authors:
24  * Rob Clark <robdclark@gmail.com>
25  * Daniel Vetter <daniel.vetter@ffwll.ch>
26  */
27 
28 
29 #include <drm/drmP.h>
30 #include <drm/drm_atomic.h>
31 #include <drm/drm_plane_helper.h>
32 
33 /**
34  * drm_atomic_state_default_release -
35  * release memory initialized by drm_atomic_state_init
36  * @state: atomic state
37  *
38  * Free all the memory allocated by drm_atomic_state_init.
39  * This is useful for drivers that subclass the atomic state.
40  */
41 void drm_atomic_state_default_release(struct drm_atomic_state *state)
42 {
43 	kfree(state->connectors);
44 	kfree(state->connector_states);
45 	kfree(state->crtcs);
46 	kfree(state->crtc_states);
47 	kfree(state->planes);
48 	kfree(state->plane_states);
49 }
50 EXPORT_SYMBOL(drm_atomic_state_default_release);
51 
52 /**
53  * drm_atomic_state_init - init new atomic state
54  * @dev: DRM device
55  * @state: atomic state
56  *
57  * Default implementation for filling in a new atomic state.
58  * This is useful for drivers that subclass the atomic state.
59  */
60 int
61 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
62 {
63 	/* TODO legacy paths should maybe do a better job about
64 	 * setting this appropriately?
65 	 */
66 	state->allow_modeset = true;
67 
68 	state->crtcs = kcalloc(dev->mode_config.num_crtc,
69 			       sizeof(*state->crtcs), GFP_KERNEL);
70 	if (!state->crtcs)
71 		goto fail;
72 	state->crtc_states = kcalloc(dev->mode_config.num_crtc,
73 				     sizeof(*state->crtc_states), GFP_KERNEL);
74 	if (!state->crtc_states)
75 		goto fail;
76 	state->planes = kcalloc(dev->mode_config.num_total_plane,
77 				sizeof(*state->planes), GFP_KERNEL);
78 	if (!state->planes)
79 		goto fail;
80 	state->plane_states = kcalloc(dev->mode_config.num_total_plane,
81 				      sizeof(*state->plane_states), GFP_KERNEL);
82 	if (!state->plane_states)
83 		goto fail;
84 
85 	state->dev = dev;
86 
87 	DRM_DEBUG_ATOMIC("Allocated atomic state %p\n", state);
88 
89 	return 0;
90 fail:
91 	drm_atomic_state_default_release(state);
92 	return -ENOMEM;
93 }
94 EXPORT_SYMBOL(drm_atomic_state_init);
95 
96 /**
97  * drm_atomic_state_alloc - allocate atomic state
98  * @dev: DRM device
99  *
100  * This allocates an empty atomic state to track updates.
101  */
102 struct drm_atomic_state *
103 drm_atomic_state_alloc(struct drm_device *dev)
104 {
105 	struct drm_mode_config *config = &dev->mode_config;
106 	struct drm_atomic_state *state;
107 
108 	if (!config->funcs->atomic_state_alloc) {
109 		state = kzalloc(sizeof(*state), GFP_KERNEL);
110 		if (!state)
111 			return NULL;
112 		if (drm_atomic_state_init(dev, state) < 0) {
113 			kfree(state);
114 			return NULL;
115 		}
116 		return state;
117 	}
118 
119 	return config->funcs->atomic_state_alloc(dev);
120 }
121 EXPORT_SYMBOL(drm_atomic_state_alloc);
122 
123 /**
124  * drm_atomic_state_default_clear - clear base atomic state
125  * @state: atomic state
126  *
127  * Default implementation for clearing atomic state.
128  * This is useful for drivers that subclass the atomic state.
129  */
130 void drm_atomic_state_default_clear(struct drm_atomic_state *state)
131 {
132 	struct drm_device *dev = state->dev;
133 	struct drm_mode_config *config = &dev->mode_config;
134 	int i;
135 
136 	DRM_DEBUG_ATOMIC("Clearing atomic state %p\n", state);
137 
138 	for (i = 0; i < state->num_connector; i++) {
139 		struct drm_connector *connector = state->connectors[i];
140 
141 		if (!connector)
142 			continue;
143 
144 		/*
145 		 * FIXME: Async commits can race with connector unplugging and
146 		 * there's currently nothing that prevents cleanup up state for
147 		 * deleted connectors. As long as the callback doesn't look at
148 		 * the connector we'll be fine though, so make sure that's the
149 		 * case by setting all connector pointers to NULL.
150 		 */
151 		state->connector_states[i]->connector = NULL;
152 		connector->funcs->atomic_destroy_state(NULL,
153 						       state->connector_states[i]);
154 		state->connectors[i] = NULL;
155 		state->connector_states[i] = NULL;
156 	}
157 
158 	for (i = 0; i < config->num_crtc; i++) {
159 		struct drm_crtc *crtc = state->crtcs[i];
160 
161 		if (!crtc)
162 			continue;
163 
164 		crtc->funcs->atomic_destroy_state(crtc,
165 						  state->crtc_states[i]);
166 		state->crtcs[i] = NULL;
167 		state->crtc_states[i] = NULL;
168 	}
169 
170 	for (i = 0; i < config->num_total_plane; i++) {
171 		struct drm_plane *plane = state->planes[i];
172 
173 		if (!plane)
174 			continue;
175 
176 		plane->funcs->atomic_destroy_state(plane,
177 						   state->plane_states[i]);
178 		state->planes[i] = NULL;
179 		state->plane_states[i] = NULL;
180 	}
181 }
182 EXPORT_SYMBOL(drm_atomic_state_default_clear);
183 
184 /**
185  * drm_atomic_state_clear - clear state object
186  * @state: atomic state
187  *
188  * When the w/w mutex algorithm detects a deadlock we need to back off and drop
189  * all locks. So someone else could sneak in and change the current modeset
190  * configuration. Which means that all the state assembled in @state is no
191  * longer an atomic update to the current state, but to some arbitrary earlier
192  * state. Which could break assumptions the driver's ->atomic_check likely
193  * relies on.
194  *
195  * Hence we must clear all cached state and completely start over, using this
196  * function.
197  */
198 void drm_atomic_state_clear(struct drm_atomic_state *state)
199 {
200 	struct drm_device *dev = state->dev;
201 	struct drm_mode_config *config = &dev->mode_config;
202 
203 	if (config->funcs->atomic_state_clear)
204 		config->funcs->atomic_state_clear(state);
205 	else
206 		drm_atomic_state_default_clear(state);
207 }
208 EXPORT_SYMBOL(drm_atomic_state_clear);
209 
210 /**
211  * drm_atomic_state_free - free all memory for an atomic state
212  * @state: atomic state to deallocate
213  *
214  * This frees all memory associated with an atomic state, including all the
215  * per-object state for planes, crtcs and connectors.
216  */
217 void drm_atomic_state_free(struct drm_atomic_state *state)
218 {
219 	struct drm_device *dev;
220 	struct drm_mode_config *config;
221 
222 	if (!state)
223 		return;
224 
225 	dev = state->dev;
226 	config = &dev->mode_config;
227 
228 	drm_atomic_state_clear(state);
229 
230 	DRM_DEBUG_ATOMIC("Freeing atomic state %p\n", state);
231 
232 	if (config->funcs->atomic_state_free) {
233 		config->funcs->atomic_state_free(state);
234 	} else {
235 		drm_atomic_state_default_release(state);
236 		kfree(state);
237 	}
238 }
239 EXPORT_SYMBOL(drm_atomic_state_free);
240 
241 /**
242  * drm_atomic_get_crtc_state - get crtc state
243  * @state: global atomic state object
244  * @crtc: crtc to get state object for
245  *
246  * This function returns the crtc state for the given crtc, allocating it if
247  * needed. It will also grab the relevant crtc lock to make sure that the state
248  * is consistent.
249  *
250  * Returns:
251  *
252  * Either the allocated state or the error code encoded into the pointer. When
253  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
254  * entire atomic sequence must be restarted. All other errors are fatal.
255  */
256 struct drm_crtc_state *
257 drm_atomic_get_crtc_state(struct drm_atomic_state *state,
258 			  struct drm_crtc *crtc)
259 {
260 	int ret, index = drm_crtc_index(crtc);
261 	struct drm_crtc_state *crtc_state;
262 
263 	crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
264 	if (crtc_state)
265 		return crtc_state;
266 
267 	ret = drm_modeset_lock(&crtc->mutex, state->acquire_ctx);
268 	if (ret)
269 		return ERR_PTR(ret);
270 
271 	crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
272 	if (!crtc_state)
273 		return ERR_PTR(-ENOMEM);
274 
275 	state->crtc_states[index] = crtc_state;
276 	state->crtcs[index] = crtc;
277 	crtc_state->state = state;
278 
279 	DRM_DEBUG_ATOMIC("Added [CRTC:%d:%s] %p state to %p\n",
280 			 crtc->base.id, crtc->name, crtc_state, state);
281 
282 	return crtc_state;
283 }
284 EXPORT_SYMBOL(drm_atomic_get_crtc_state);
285 
286 /**
287  * drm_atomic_set_mode_for_crtc - set mode for CRTC
288  * @state: the CRTC whose incoming state to update
289  * @mode: kernel-internal mode to use for the CRTC, or NULL to disable
290  *
291  * Set a mode (originating from the kernel) on the desired CRTC state. Does
292  * not change any other state properties, including enable, active, or
293  * mode_changed.
294  *
295  * RETURNS:
296  * Zero on success, error code on failure. Cannot return -EDEADLK.
297  */
298 int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
299 				 struct drm_display_mode *mode)
300 {
301 	struct drm_mode_modeinfo umode;
302 
303 	/* Early return for no change. */
304 	if (mode && memcmp(&state->mode, mode, sizeof(*mode)) == 0)
305 		return 0;
306 
307 	drm_property_unreference_blob(state->mode_blob);
308 	state->mode_blob = NULL;
309 
310 	if (mode) {
311 		drm_mode_convert_to_umode(&umode, mode);
312 		state->mode_blob =
313 			drm_property_create_blob(state->crtc->dev,
314 		                                 sizeof(umode),
315 		                                 &umode);
316 		if (IS_ERR(state->mode_blob))
317 			return PTR_ERR(state->mode_blob);
318 
319 		drm_mode_copy(&state->mode, mode);
320 		state->enable = true;
321 		DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
322 				 mode->name, state);
323 	} else {
324 		memset(&state->mode, 0, sizeof(state->mode));
325 		state->enable = false;
326 		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
327 				 state);
328 	}
329 
330 	return 0;
331 }
332 EXPORT_SYMBOL(drm_atomic_set_mode_for_crtc);
333 
334 /**
335  * drm_atomic_set_mode_prop_for_crtc - set mode for CRTC
336  * @state: the CRTC whose incoming state to update
337  * @blob: pointer to blob property to use for mode
338  *
339  * Set a mode (originating from a blob property) on the desired CRTC state.
340  * This function will take a reference on the blob property for the CRTC state,
341  * and release the reference held on the state's existing mode property, if any
342  * was set.
343  *
344  * RETURNS:
345  * Zero on success, error code on failure. Cannot return -EDEADLK.
346  */
347 int drm_atomic_set_mode_prop_for_crtc(struct drm_crtc_state *state,
348                                       struct drm_property_blob *blob)
349 {
350 	if (blob == state->mode_blob)
351 		return 0;
352 
353 	drm_property_unreference_blob(state->mode_blob);
354 	state->mode_blob = NULL;
355 
356 	if (blob) {
357 		if (blob->length != sizeof(struct drm_mode_modeinfo) ||
358 		    drm_mode_convert_umode(&state->mode,
359 		                           (const struct drm_mode_modeinfo *)
360 		                            blob->data))
361 			return -EINVAL;
362 
363 		state->mode_blob = drm_property_reference_blob(blob);
364 		state->enable = true;
365 		DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
366 				 state->mode.name, state);
367 	} else {
368 		memset(&state->mode, 0, sizeof(state->mode));
369 		state->enable = false;
370 		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
371 				 state);
372 	}
373 
374 	return 0;
375 }
376 EXPORT_SYMBOL(drm_atomic_set_mode_prop_for_crtc);
377 
378 /**
379  * drm_atomic_crtc_set_property - set property on CRTC
380  * @crtc: the drm CRTC to set a property on
381  * @state: the state object to update with the new property value
382  * @property: the property to set
383  * @val: the new property value
384  *
385  * Use this instead of calling crtc->atomic_set_property directly.
386  * This function handles generic/core properties and calls out to
387  * driver's ->atomic_set_property() for driver properties.  To ensure
388  * consistent behavior you must call this function rather than the
389  * driver hook directly.
390  *
391  * RETURNS:
392  * Zero on success, error code on failure
393  */
394 int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
395 		struct drm_crtc_state *state, struct drm_property *property,
396 		uint64_t val)
397 {
398 	struct drm_device *dev = crtc->dev;
399 	struct drm_mode_config *config = &dev->mode_config;
400 	int ret;
401 
402 	if (property == config->prop_active)
403 		state->active = val;
404 	else if (property == config->prop_mode_id) {
405 		struct drm_property_blob *mode =
406 			drm_property_lookup_blob(dev, val);
407 		ret = drm_atomic_set_mode_prop_for_crtc(state, mode);
408 		drm_property_unreference_blob(mode);
409 		return ret;
410 	}
411 	else if (crtc->funcs->atomic_set_property)
412 		return crtc->funcs->atomic_set_property(crtc, state, property, val);
413 	else
414 		return -EINVAL;
415 
416 	return 0;
417 }
418 EXPORT_SYMBOL(drm_atomic_crtc_set_property);
419 
420 /**
421  * drm_atomic_crtc_get_property - get property value from CRTC state
422  * @crtc: the drm CRTC to set a property on
423  * @state: the state object to get the property value from
424  * @property: the property to set
425  * @val: return location for the property value
426  *
427  * This function handles generic/core properties and calls out to
428  * driver's ->atomic_get_property() for driver properties.  To ensure
429  * consistent behavior you must call this function rather than the
430  * driver hook directly.
431  *
432  * RETURNS:
433  * Zero on success, error code on failure
434  */
435 static int
436 drm_atomic_crtc_get_property(struct drm_crtc *crtc,
437 		const struct drm_crtc_state *state,
438 		struct drm_property *property, uint64_t *val)
439 {
440 	struct drm_device *dev = crtc->dev;
441 	struct drm_mode_config *config = &dev->mode_config;
442 
443 	if (property == config->prop_active)
444 		*val = state->active;
445 	else if (property == config->prop_mode_id)
446 		*val = (state->mode_blob) ? state->mode_blob->base.id : 0;
447 	else if (crtc->funcs->atomic_get_property)
448 		return crtc->funcs->atomic_get_property(crtc, state, property, val);
449 	else
450 		return -EINVAL;
451 
452 	return 0;
453 }
454 
455 /**
456  * drm_atomic_crtc_check - check crtc state
457  * @crtc: crtc to check
458  * @state: crtc state to check
459  *
460  * Provides core sanity checks for crtc state.
461  *
462  * RETURNS:
463  * Zero on success, error code on failure
464  */
465 static int drm_atomic_crtc_check(struct drm_crtc *crtc,
466 		struct drm_crtc_state *state)
467 {
468 	/* NOTE: we explicitly don't enforce constraints such as primary
469 	 * layer covering entire screen, since that is something we want
470 	 * to allow (on hw that supports it).  For hw that does not, it
471 	 * should be checked in driver's crtc->atomic_check() vfunc.
472 	 *
473 	 * TODO: Add generic modeset state checks once we support those.
474 	 */
475 
476 	if (state->active && !state->enable) {
477 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] active without enabled\n",
478 				 crtc->base.id, crtc->name);
479 		return -EINVAL;
480 	}
481 
482 	/* The state->enable vs. state->mode_blob checks can be WARN_ON,
483 	 * as this is a kernel-internal detail that userspace should never
484 	 * be able to trigger. */
485 	if (drm_core_check_feature(crtc->dev, DRIVER_ATOMIC) &&
486 	    WARN_ON(state->enable && !state->mode_blob)) {
487 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enabled without mode blob\n",
488 				 crtc->base.id, crtc->name);
489 		return -EINVAL;
490 	}
491 
492 	if (drm_core_check_feature(crtc->dev, DRIVER_ATOMIC) &&
493 	    WARN_ON(!state->enable && state->mode_blob)) {
494 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] disabled with mode blob\n",
495 				 crtc->base.id, crtc->name);
496 		return -EINVAL;
497 	}
498 
499 	/*
500 	 * Reject event generation for when a CRTC is off and stays off.
501 	 * It wouldn't be hard to implement this, but userspace has a track
502 	 * record of happily burning through 100% cpu (or worse, crash) when the
503 	 * display pipe is suspended. To avoid all that fun just reject updates
504 	 * that ask for events since likely that indicates a bug in the
505 	 * compositor's drawing loop. This is consistent with the vblank IOCTL
506 	 * and legacy page_flip IOCTL which also reject service on a disabled
507 	 * pipe.
508 	 */
509 	if (state->event && !state->active && !crtc->state->active) {
510 		DRM_DEBUG_ATOMIC("[CRTC:%d] requesting event but off\n",
511 				 crtc->base.id);
512 		return -EINVAL;
513 	}
514 
515 	return 0;
516 }
517 
518 /**
519  * drm_atomic_get_plane_state - get plane state
520  * @state: global atomic state object
521  * @plane: plane to get state object for
522  *
523  * This function returns the plane state for the given plane, allocating it if
524  * needed. It will also grab the relevant plane lock to make sure that the state
525  * is consistent.
526  *
527  * Returns:
528  *
529  * Either the allocated state or the error code encoded into the pointer. When
530  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
531  * entire atomic sequence must be restarted. All other errors are fatal.
532  */
533 struct drm_plane_state *
534 drm_atomic_get_plane_state(struct drm_atomic_state *state,
535 			  struct drm_plane *plane)
536 {
537 	int ret, index = drm_plane_index(plane);
538 	struct drm_plane_state *plane_state;
539 
540 	plane_state = drm_atomic_get_existing_plane_state(state, plane);
541 	if (plane_state)
542 		return plane_state;
543 
544 	ret = drm_modeset_lock(&plane->mutex, state->acquire_ctx);
545 	if (ret)
546 		return ERR_PTR(ret);
547 
548 	plane_state = plane->funcs->atomic_duplicate_state(plane);
549 	if (!plane_state)
550 		return ERR_PTR(-ENOMEM);
551 
552 	state->plane_states[index] = plane_state;
553 	state->planes[index] = plane;
554 	plane_state->state = state;
555 
556 	DRM_DEBUG_ATOMIC("Added [PLANE:%d:%s] %p state to %p\n",
557 			 plane->base.id, plane->name, plane_state, state);
558 
559 	if (plane_state->crtc) {
560 		struct drm_crtc_state *crtc_state;
561 
562 		crtc_state = drm_atomic_get_crtc_state(state,
563 						       plane_state->crtc);
564 		if (IS_ERR(crtc_state))
565 			return ERR_CAST(crtc_state);
566 	}
567 
568 	return plane_state;
569 }
570 EXPORT_SYMBOL(drm_atomic_get_plane_state);
571 
572 /**
573  * drm_atomic_plane_set_property - set property on plane
574  * @plane: the drm plane to set a property on
575  * @state: the state object to update with the new property value
576  * @property: the property to set
577  * @val: the new property value
578  *
579  * Use this instead of calling plane->atomic_set_property directly.
580  * This function handles generic/core properties and calls out to
581  * driver's ->atomic_set_property() for driver properties.  To ensure
582  * consistent behavior you must call this function rather than the
583  * driver hook directly.
584  *
585  * RETURNS:
586  * Zero on success, error code on failure
587  */
588 int drm_atomic_plane_set_property(struct drm_plane *plane,
589 		struct drm_plane_state *state, struct drm_property *property,
590 		uint64_t val)
591 {
592 	struct drm_device *dev = plane->dev;
593 	struct drm_mode_config *config = &dev->mode_config;
594 
595 	if (property == config->prop_fb_id) {
596 		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, val);
597 		drm_atomic_set_fb_for_plane(state, fb);
598 		if (fb)
599 			drm_framebuffer_unreference(fb);
600 	} else if (property == config->prop_crtc_id) {
601 		struct drm_crtc *crtc = drm_crtc_find(dev, val);
602 		return drm_atomic_set_crtc_for_plane(state, crtc);
603 	} else if (property == config->prop_crtc_x) {
604 		state->crtc_x = U642I64(val);
605 	} else if (property == config->prop_crtc_y) {
606 		state->crtc_y = U642I64(val);
607 	} else if (property == config->prop_crtc_w) {
608 		state->crtc_w = val;
609 	} else if (property == config->prop_crtc_h) {
610 		state->crtc_h = val;
611 	} else if (property == config->prop_src_x) {
612 		state->src_x = val;
613 	} else if (property == config->prop_src_y) {
614 		state->src_y = val;
615 	} else if (property == config->prop_src_w) {
616 		state->src_w = val;
617 	} else if (property == config->prop_src_h) {
618 		state->src_h = val;
619 	} else if (property == config->rotation_property) {
620 		state->rotation = val;
621 	} else if (plane->funcs->atomic_set_property) {
622 		return plane->funcs->atomic_set_property(plane, state,
623 				property, val);
624 	} else {
625 		return -EINVAL;
626 	}
627 
628 	return 0;
629 }
630 EXPORT_SYMBOL(drm_atomic_plane_set_property);
631 
632 /**
633  * drm_atomic_plane_get_property - get property value from plane state
634  * @plane: the drm plane to set a property on
635  * @state: the state object to get the property value from
636  * @property: the property to set
637  * @val: return location for the property value
638  *
639  * This function handles generic/core properties and calls out to
640  * driver's ->atomic_get_property() for driver properties.  To ensure
641  * consistent behavior you must call this function rather than the
642  * driver hook directly.
643  *
644  * RETURNS:
645  * Zero on success, error code on failure
646  */
647 static int
648 drm_atomic_plane_get_property(struct drm_plane *plane,
649 		const struct drm_plane_state *state,
650 		struct drm_property *property, uint64_t *val)
651 {
652 	struct drm_device *dev = plane->dev;
653 	struct drm_mode_config *config = &dev->mode_config;
654 
655 	if (property == config->prop_fb_id) {
656 		*val = (state->fb) ? state->fb->base.id : 0;
657 	} else if (property == config->prop_crtc_id) {
658 		*val = (state->crtc) ? state->crtc->base.id : 0;
659 	} else if (property == config->prop_crtc_x) {
660 		*val = I642U64(state->crtc_x);
661 	} else if (property == config->prop_crtc_y) {
662 		*val = I642U64(state->crtc_y);
663 	} else if (property == config->prop_crtc_w) {
664 		*val = state->crtc_w;
665 	} else if (property == config->prop_crtc_h) {
666 		*val = state->crtc_h;
667 	} else if (property == config->prop_src_x) {
668 		*val = state->src_x;
669 	} else if (property == config->prop_src_y) {
670 		*val = state->src_y;
671 	} else if (property == config->prop_src_w) {
672 		*val = state->src_w;
673 	} else if (property == config->prop_src_h) {
674 		*val = state->src_h;
675 	} else if (property == config->rotation_property) {
676 		*val = state->rotation;
677 	} else if (plane->funcs->atomic_get_property) {
678 		return plane->funcs->atomic_get_property(plane, state, property, val);
679 	} else {
680 		return -EINVAL;
681 	}
682 
683 	return 0;
684 }
685 
686 static bool
687 plane_switching_crtc(struct drm_atomic_state *state,
688 		     struct drm_plane *plane,
689 		     struct drm_plane_state *plane_state)
690 {
691 	if (!plane->state->crtc || !plane_state->crtc)
692 		return false;
693 
694 	if (plane->state->crtc == plane_state->crtc)
695 		return false;
696 
697 	/* This could be refined, but currently there's no helper or driver code
698 	 * to implement direct switching of active planes nor userspace to take
699 	 * advantage of more direct plane switching without the intermediate
700 	 * full OFF state.
701 	 */
702 	return true;
703 }
704 
705 /**
706  * drm_atomic_plane_check - check plane state
707  * @plane: plane to check
708  * @state: plane state to check
709  *
710  * Provides core sanity checks for plane state.
711  *
712  * RETURNS:
713  * Zero on success, error code on failure
714  */
715 static int drm_atomic_plane_check(struct drm_plane *plane,
716 		struct drm_plane_state *state)
717 {
718 	unsigned int fb_width, fb_height;
719 	int ret;
720 
721 	/* either *both* CRTC and FB must be set, or neither */
722 	if (WARN_ON(state->crtc && !state->fb)) {
723 		DRM_DEBUG_ATOMIC("CRTC set but no FB\n");
724 		return -EINVAL;
725 	} else if (WARN_ON(state->fb && !state->crtc)) {
726 		DRM_DEBUG_ATOMIC("FB set but no CRTC\n");
727 		return -EINVAL;
728 	}
729 
730 	/* if disabled, we don't care about the rest of the state: */
731 	if (!state->crtc)
732 		return 0;
733 
734 	/* Check whether this plane is usable on this CRTC */
735 	if (!(plane->possible_crtcs & drm_crtc_mask(state->crtc))) {
736 		DRM_DEBUG_ATOMIC("Invalid crtc for plane\n");
737 		return -EINVAL;
738 	}
739 
740 	/* Check whether this plane supports the fb pixel format. */
741 	ret = drm_plane_check_pixel_format(plane, state->fb->pixel_format);
742 	if (ret) {
743 		DRM_DEBUG_ATOMIC("Invalid pixel format %s\n",
744 				 drm_get_format_name(state->fb->pixel_format));
745 		return ret;
746 	}
747 
748 	/* Give drivers some help against integer overflows */
749 	if (state->crtc_w > INT_MAX ||
750 	    state->crtc_x > INT_MAX - (int32_t) state->crtc_w ||
751 	    state->crtc_h > INT_MAX ||
752 	    state->crtc_y > INT_MAX - (int32_t) state->crtc_h) {
753 		DRM_DEBUG_ATOMIC("Invalid CRTC coordinates %ux%u+%d+%d\n",
754 				 state->crtc_w, state->crtc_h,
755 				 state->crtc_x, state->crtc_y);
756 		return -ERANGE;
757 	}
758 
759 	fb_width = state->fb->width << 16;
760 	fb_height = state->fb->height << 16;
761 
762 	/* Make sure source coordinates are inside the fb. */
763 	if (state->src_w > fb_width ||
764 	    state->src_x > fb_width - state->src_w ||
765 	    state->src_h > fb_height ||
766 	    state->src_y > fb_height - state->src_h) {
767 		DRM_DEBUG_ATOMIC("Invalid source coordinates "
768 				 "%u.%06ux%u.%06u+%u.%06u+%u.%06u\n",
769 				 state->src_w >> 16, ((state->src_w & 0xffff) * 15625) >> 10,
770 				 state->src_h >> 16, ((state->src_h & 0xffff) * 15625) >> 10,
771 				 state->src_x >> 16, ((state->src_x & 0xffff) * 15625) >> 10,
772 				 state->src_y >> 16, ((state->src_y & 0xffff) * 15625) >> 10);
773 		return -ENOSPC;
774 	}
775 
776 	if (plane_switching_crtc(state->state, plane, state)) {
777 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] switching CRTC directly\n",
778 				 plane->base.id, plane->name);
779 		return -EINVAL;
780 	}
781 
782 	return 0;
783 }
784 
785 /**
786  * drm_atomic_get_connector_state - get connector state
787  * @state: global atomic state object
788  * @connector: connector to get state object for
789  *
790  * This function returns the connector state for the given connector,
791  * allocating it if needed. It will also grab the relevant connector lock to
792  * make sure that the state is consistent.
793  *
794  * Returns:
795  *
796  * Either the allocated state or the error code encoded into the pointer. When
797  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
798  * entire atomic sequence must be restarted. All other errors are fatal.
799  */
800 struct drm_connector_state *
801 drm_atomic_get_connector_state(struct drm_atomic_state *state,
802 			  struct drm_connector *connector)
803 {
804 	int ret, index;
805 	struct drm_mode_config *config = &connector->dev->mode_config;
806 	struct drm_connector_state *connector_state;
807 
808 	ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx);
809 	if (ret)
810 		return ERR_PTR(ret);
811 
812 	index = drm_connector_index(connector);
813 
814 	if (index >= state->num_connector) {
815 		struct drm_connector **c;
816 		struct drm_connector_state **cs;
817 		int alloc = max(index + 1, config->num_connector);
818 
819 		c = krealloc(state->connectors, alloc * sizeof(*state->connectors), GFP_KERNEL);
820 		if (!c)
821 			return ERR_PTR(-ENOMEM);
822 
823 		state->connectors = c;
824 		memset(&state->connectors[state->num_connector], 0,
825 		       sizeof(*state->connectors) * (alloc - state->num_connector));
826 
827 		cs = krealloc(state->connector_states, alloc * sizeof(*state->connector_states), GFP_KERNEL);
828 		if (!cs)
829 			return ERR_PTR(-ENOMEM);
830 
831 		state->connector_states = cs;
832 		memset(&state->connector_states[state->num_connector], 0,
833 		       sizeof(*state->connector_states) * (alloc - state->num_connector));
834 		state->num_connector = alloc;
835 	}
836 
837 	if (state->connector_states[index])
838 		return state->connector_states[index];
839 
840 	connector_state = connector->funcs->atomic_duplicate_state(connector);
841 	if (!connector_state)
842 		return ERR_PTR(-ENOMEM);
843 
844 	state->connector_states[index] = connector_state;
845 	state->connectors[index] = connector;
846 	connector_state->state = state;
847 
848 	DRM_DEBUG_ATOMIC("Added [CONNECTOR:%d] %p state to %p\n",
849 			 connector->base.id, connector_state, state);
850 
851 	if (connector_state->crtc) {
852 		struct drm_crtc_state *crtc_state;
853 
854 		crtc_state = drm_atomic_get_crtc_state(state,
855 						       connector_state->crtc);
856 		if (IS_ERR(crtc_state))
857 			return ERR_CAST(crtc_state);
858 	}
859 
860 	return connector_state;
861 }
862 EXPORT_SYMBOL(drm_atomic_get_connector_state);
863 
864 /**
865  * drm_atomic_connector_set_property - set property on connector.
866  * @connector: the drm connector to set a property on
867  * @state: the state object to update with the new property value
868  * @property: the property to set
869  * @val: the new property value
870  *
871  * Use this instead of calling connector->atomic_set_property directly.
872  * This function handles generic/core properties and calls out to
873  * driver's ->atomic_set_property() for driver properties.  To ensure
874  * consistent behavior you must call this function rather than the
875  * driver hook directly.
876  *
877  * RETURNS:
878  * Zero on success, error code on failure
879  */
880 int drm_atomic_connector_set_property(struct drm_connector *connector,
881 		struct drm_connector_state *state, struct drm_property *property,
882 		uint64_t val)
883 {
884 	struct drm_device *dev = connector->dev;
885 	struct drm_mode_config *config = &dev->mode_config;
886 
887 	if (property == config->prop_crtc_id) {
888 		struct drm_crtc *crtc = drm_crtc_find(dev, val);
889 		return drm_atomic_set_crtc_for_connector(state, crtc);
890 	} else if (property == config->dpms_property) {
891 		/* setting DPMS property requires special handling, which
892 		 * is done in legacy setprop path for us.  Disallow (for
893 		 * now?) atomic writes to DPMS property:
894 		 */
895 		return -EINVAL;
896 	} else if (connector->funcs->atomic_set_property) {
897 		return connector->funcs->atomic_set_property(connector,
898 				state, property, val);
899 	} else {
900 		return -EINVAL;
901 	}
902 }
903 EXPORT_SYMBOL(drm_atomic_connector_set_property);
904 
905 /**
906  * drm_atomic_connector_get_property - get property value from connector state
907  * @connector: the drm connector to set a property on
908  * @state: the state object to get the property value from
909  * @property: the property to set
910  * @val: return location for the property value
911  *
912  * This function handles generic/core properties and calls out to
913  * driver's ->atomic_get_property() for driver properties.  To ensure
914  * consistent behavior you must call this function rather than the
915  * driver hook directly.
916  *
917  * RETURNS:
918  * Zero on success, error code on failure
919  */
920 static int
921 drm_atomic_connector_get_property(struct drm_connector *connector,
922 		const struct drm_connector_state *state,
923 		struct drm_property *property, uint64_t *val)
924 {
925 	struct drm_device *dev = connector->dev;
926 	struct drm_mode_config *config = &dev->mode_config;
927 
928 	if (property == config->prop_crtc_id) {
929 		*val = (state->crtc) ? state->crtc->base.id : 0;
930 	} else if (property == config->dpms_property) {
931 		*val = connector->dpms;
932 	} else if (connector->funcs->atomic_get_property) {
933 		return connector->funcs->atomic_get_property(connector,
934 				state, property, val);
935 	} else {
936 		return -EINVAL;
937 	}
938 
939 	return 0;
940 }
941 
942 int drm_atomic_get_property(struct drm_mode_object *obj,
943 		struct drm_property *property, uint64_t *val)
944 {
945 	struct drm_device *dev = property->dev;
946 	int ret;
947 
948 	switch (obj->type) {
949 	case DRM_MODE_OBJECT_CONNECTOR: {
950 		struct drm_connector *connector = obj_to_connector(obj);
951 		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
952 		ret = drm_atomic_connector_get_property(connector,
953 				connector->state, property, val);
954 		break;
955 	}
956 	case DRM_MODE_OBJECT_CRTC: {
957 		struct drm_crtc *crtc = obj_to_crtc(obj);
958 		WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
959 		ret = drm_atomic_crtc_get_property(crtc,
960 				crtc->state, property, val);
961 		break;
962 	}
963 	case DRM_MODE_OBJECT_PLANE: {
964 		struct drm_plane *plane = obj_to_plane(obj);
965 		WARN_ON(!drm_modeset_is_locked(&plane->mutex));
966 		ret = drm_atomic_plane_get_property(plane,
967 				plane->state, property, val);
968 		break;
969 	}
970 	default:
971 		ret = -EINVAL;
972 		break;
973 	}
974 
975 	return ret;
976 }
977 
978 /**
979  * drm_atomic_set_crtc_for_plane - set crtc for plane
980  * @plane_state: the plane whose incoming state to update
981  * @crtc: crtc to use for the plane
982  *
983  * Changing the assigned crtc for a plane requires us to grab the lock and state
984  * for the new crtc, as needed. This function takes care of all these details
985  * besides updating the pointer in the state object itself.
986  *
987  * Returns:
988  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
989  * then the w/w mutex code has detected a deadlock and the entire atomic
990  * sequence must be restarted. All other errors are fatal.
991  */
992 int
993 drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
994 			      struct drm_crtc *crtc)
995 {
996 	struct drm_plane *plane = plane_state->plane;
997 	struct drm_crtc_state *crtc_state;
998 
999 	if (plane_state->crtc) {
1000 		crtc_state = drm_atomic_get_crtc_state(plane_state->state,
1001 						       plane_state->crtc);
1002 		if (WARN_ON(IS_ERR(crtc_state)))
1003 			return PTR_ERR(crtc_state);
1004 
1005 		crtc_state->plane_mask &= ~(1 << drm_plane_index(plane));
1006 	}
1007 
1008 	plane_state->crtc = crtc;
1009 
1010 	if (crtc) {
1011 		crtc_state = drm_atomic_get_crtc_state(plane_state->state,
1012 						       crtc);
1013 		if (IS_ERR(crtc_state))
1014 			return PTR_ERR(crtc_state);
1015 		crtc_state->plane_mask |= (1 << drm_plane_index(plane));
1016 	}
1017 
1018 	if (crtc)
1019 		DRM_DEBUG_ATOMIC("Link plane state %p to [CRTC:%d:%s]\n",
1020 				 plane_state, crtc->base.id, crtc->name);
1021 	else
1022 		DRM_DEBUG_ATOMIC("Link plane state %p to [NOCRTC]\n",
1023 				 plane_state);
1024 
1025 	return 0;
1026 }
1027 EXPORT_SYMBOL(drm_atomic_set_crtc_for_plane);
1028 
1029 /**
1030  * drm_atomic_set_fb_for_plane - set framebuffer for plane
1031  * @plane_state: atomic state object for the plane
1032  * @fb: fb to use for the plane
1033  *
1034  * Changing the assigned framebuffer for a plane requires us to grab a reference
1035  * to the new fb and drop the reference to the old fb, if there is one. This
1036  * function takes care of all these details besides updating the pointer in the
1037  * state object itself.
1038  */
1039 void
1040 drm_atomic_set_fb_for_plane(struct drm_plane_state *plane_state,
1041 			    struct drm_framebuffer *fb)
1042 {
1043 	if (plane_state->fb)
1044 		drm_framebuffer_unreference(plane_state->fb);
1045 	if (fb)
1046 		drm_framebuffer_reference(fb);
1047 	plane_state->fb = fb;
1048 
1049 	if (fb)
1050 		DRM_DEBUG_ATOMIC("Set [FB:%d] for plane state %p\n",
1051 				 fb->base.id, plane_state);
1052 	else
1053 		DRM_DEBUG_ATOMIC("Set [NOFB] for plane state %p\n",
1054 				 plane_state);
1055 }
1056 EXPORT_SYMBOL(drm_atomic_set_fb_for_plane);
1057 
1058 /**
1059  * drm_atomic_set_crtc_for_connector - set crtc for connector
1060  * @conn_state: atomic state object for the connector
1061  * @crtc: crtc to use for the connector
1062  *
1063  * Changing the assigned crtc for a connector requires us to grab the lock and
1064  * state for the new crtc, as needed. This function takes care of all these
1065  * details besides updating the pointer in the state object itself.
1066  *
1067  * Returns:
1068  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1069  * then the w/w mutex code has detected a deadlock and the entire atomic
1070  * sequence must be restarted. All other errors are fatal.
1071  */
1072 int
1073 drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
1074 				  struct drm_crtc *crtc)
1075 {
1076 	struct drm_crtc_state *crtc_state;
1077 
1078 	if (conn_state->crtc && conn_state->crtc != crtc) {
1079 		crtc_state = drm_atomic_get_existing_crtc_state(conn_state->state,
1080 								conn_state->crtc);
1081 
1082 		crtc_state->connector_mask &=
1083 			~(1 << drm_connector_index(conn_state->connector));
1084 	}
1085 
1086 	if (crtc) {
1087 		crtc_state = drm_atomic_get_crtc_state(conn_state->state, crtc);
1088 		if (IS_ERR(crtc_state))
1089 			return PTR_ERR(crtc_state);
1090 
1091 		crtc_state->connector_mask |=
1092 			1 << drm_connector_index(conn_state->connector);
1093 	}
1094 
1095 	conn_state->crtc = crtc;
1096 
1097 	if (crtc)
1098 		DRM_DEBUG_ATOMIC("Link connector state %p to [CRTC:%d:%s]\n",
1099 				 conn_state, crtc->base.id, crtc->name);
1100 	else
1101 		DRM_DEBUG_ATOMIC("Link connector state %p to [NOCRTC]\n",
1102 				 conn_state);
1103 
1104 	return 0;
1105 }
1106 EXPORT_SYMBOL(drm_atomic_set_crtc_for_connector);
1107 
1108 /**
1109  * drm_atomic_add_affected_connectors - add connectors for crtc
1110  * @state: atomic state
1111  * @crtc: DRM crtc
1112  *
1113  * This function walks the current configuration and adds all connectors
1114  * currently using @crtc to the atomic configuration @state. Note that this
1115  * function must acquire the connection mutex. This can potentially cause
1116  * unneeded seralization if the update is just for the planes on one crtc. Hence
1117  * drivers and helpers should only call this when really needed (e.g. when a
1118  * full modeset needs to happen due to some change).
1119  *
1120  * Returns:
1121  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1122  * then the w/w mutex code has detected a deadlock and the entire atomic
1123  * sequence must be restarted. All other errors are fatal.
1124  */
1125 int
1126 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
1127 				   struct drm_crtc *crtc)
1128 {
1129 	struct drm_mode_config *config = &state->dev->mode_config;
1130 	struct drm_connector *connector;
1131 	struct drm_connector_state *conn_state;
1132 	int ret;
1133 
1134 	ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx);
1135 	if (ret)
1136 		return ret;
1137 
1138 	DRM_DEBUG_ATOMIC("Adding all current connectors for [CRTC:%d:%s] to %p\n",
1139 			 crtc->base.id, crtc->name, state);
1140 
1141 	/*
1142 	 * Changed connectors are already in @state, so only need to look at the
1143 	 * current configuration.
1144 	 */
1145 	drm_for_each_connector(connector, state->dev) {
1146 		if (connector->state->crtc != crtc)
1147 			continue;
1148 
1149 		conn_state = drm_atomic_get_connector_state(state, connector);
1150 		if (IS_ERR(conn_state))
1151 			return PTR_ERR(conn_state);
1152 	}
1153 
1154 	return 0;
1155 }
1156 EXPORT_SYMBOL(drm_atomic_add_affected_connectors);
1157 
1158 /**
1159  * drm_atomic_add_affected_planes - add planes for crtc
1160  * @state: atomic state
1161  * @crtc: DRM crtc
1162  *
1163  * This function walks the current configuration and adds all planes
1164  * currently used by @crtc to the atomic configuration @state. This is useful
1165  * when an atomic commit also needs to check all currently enabled plane on
1166  * @crtc, e.g. when changing the mode. It's also useful when re-enabling a CRTC
1167  * to avoid special code to force-enable all planes.
1168  *
1169  * Since acquiring a plane state will always also acquire the w/w mutex of the
1170  * current CRTC for that plane (if there is any) adding all the plane states for
1171  * a CRTC will not reduce parallism of atomic updates.
1172  *
1173  * Returns:
1174  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1175  * then the w/w mutex code has detected a deadlock and the entire atomic
1176  * sequence must be restarted. All other errors are fatal.
1177  */
1178 int
1179 drm_atomic_add_affected_planes(struct drm_atomic_state *state,
1180 			       struct drm_crtc *crtc)
1181 {
1182 	struct drm_plane *plane;
1183 
1184 	WARN_ON(!drm_atomic_get_existing_crtc_state(state, crtc));
1185 
1186 	drm_for_each_plane_mask(plane, state->dev, crtc->state->plane_mask) {
1187 		struct drm_plane_state *plane_state =
1188 			drm_atomic_get_plane_state(state, plane);
1189 
1190 		if (IS_ERR(plane_state))
1191 			return PTR_ERR(plane_state);
1192 	}
1193 	return 0;
1194 }
1195 EXPORT_SYMBOL(drm_atomic_add_affected_planes);
1196 
1197 /**
1198  * drm_atomic_legacy_backoff - locking backoff for legacy ioctls
1199  * @state: atomic state
1200  *
1201  * This function should be used by legacy entry points which don't understand
1202  * -EDEADLK semantics. For simplicity this one will grab all modeset locks after
1203  * the slowpath completed.
1204  */
1205 void drm_atomic_legacy_backoff(struct drm_atomic_state *state)
1206 {
1207 	int ret;
1208 
1209 retry:
1210 	drm_modeset_backoff(state->acquire_ctx);
1211 
1212 	ret = drm_modeset_lock_all_ctx(state->dev, state->acquire_ctx);
1213 	if (ret)
1214 		goto retry;
1215 }
1216 EXPORT_SYMBOL(drm_atomic_legacy_backoff);
1217 
1218 /**
1219  * drm_atomic_check_only - check whether a given config would work
1220  * @state: atomic configuration to check
1221  *
1222  * Note that this function can return -EDEADLK if the driver needed to acquire
1223  * more locks but encountered a deadlock. The caller must then do the usual w/w
1224  * backoff dance and restart. All other errors are fatal.
1225  *
1226  * Returns:
1227  * 0 on success, negative error code on failure.
1228  */
1229 int drm_atomic_check_only(struct drm_atomic_state *state)
1230 {
1231 	struct drm_device *dev = state->dev;
1232 	struct drm_mode_config *config = &dev->mode_config;
1233 	struct drm_plane *plane;
1234 	struct drm_plane_state *plane_state;
1235 	struct drm_crtc *crtc;
1236 	struct drm_crtc_state *crtc_state;
1237 	int i, ret = 0;
1238 
1239 	DRM_DEBUG_ATOMIC("checking %p\n", state);
1240 
1241 	for_each_plane_in_state(state, plane, plane_state, i) {
1242 		ret = drm_atomic_plane_check(plane, plane_state);
1243 		if (ret) {
1244 			DRM_DEBUG_ATOMIC("[PLANE:%d:%s] atomic core check failed\n",
1245 					 plane->base.id, plane->name);
1246 			return ret;
1247 		}
1248 	}
1249 
1250 	for_each_crtc_in_state(state, crtc, crtc_state, i) {
1251 		ret = drm_atomic_crtc_check(crtc, crtc_state);
1252 		if (ret) {
1253 			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] atomic core check failed\n",
1254 					 crtc->base.id, crtc->name);
1255 			return ret;
1256 		}
1257 	}
1258 
1259 	if (config->funcs->atomic_check)
1260 		ret = config->funcs->atomic_check(state->dev, state);
1261 
1262 	if (!state->allow_modeset) {
1263 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1264 			if (drm_atomic_crtc_needs_modeset(crtc_state)) {
1265 				DRM_DEBUG_ATOMIC("[CRTC:%d:%s] requires full modeset\n",
1266 						 crtc->base.id, crtc->name);
1267 				return -EINVAL;
1268 			}
1269 		}
1270 	}
1271 
1272 	return ret;
1273 }
1274 EXPORT_SYMBOL(drm_atomic_check_only);
1275 
1276 /**
1277  * drm_atomic_commit - commit configuration atomically
1278  * @state: atomic configuration to check
1279  *
1280  * Note that this function can return -EDEADLK if the driver needed to acquire
1281  * more locks but encountered a deadlock. The caller must then do the usual w/w
1282  * backoff dance and restart. All other errors are fatal.
1283  *
1284  * Also note that on successful execution ownership of @state is transferred
1285  * from the caller of this function to the function itself. The caller must not
1286  * free or in any other way access @state. If the function fails then the caller
1287  * must clean up @state itself.
1288  *
1289  * Returns:
1290  * 0 on success, negative error code on failure.
1291  */
1292 int drm_atomic_commit(struct drm_atomic_state *state)
1293 {
1294 	struct drm_mode_config *config = &state->dev->mode_config;
1295 	int ret;
1296 
1297 	ret = drm_atomic_check_only(state);
1298 	if (ret)
1299 		return ret;
1300 
1301 	DRM_DEBUG_ATOMIC("commiting %p\n", state);
1302 
1303 	return config->funcs->atomic_commit(state->dev, state, false);
1304 }
1305 EXPORT_SYMBOL(drm_atomic_commit);
1306 
1307 /**
1308  * drm_atomic_async_commit - atomic&async configuration commit
1309  * @state: atomic configuration to check
1310  *
1311  * Note that this function can return -EDEADLK if the driver needed to acquire
1312  * more locks but encountered a deadlock. The caller must then do the usual w/w
1313  * backoff dance and restart. All other errors are fatal.
1314  *
1315  * Also note that on successful execution ownership of @state is transferred
1316  * from the caller of this function to the function itself. The caller must not
1317  * free or in any other way access @state. If the function fails then the caller
1318  * must clean up @state itself.
1319  *
1320  * Returns:
1321  * 0 on success, negative error code on failure.
1322  */
1323 int drm_atomic_async_commit(struct drm_atomic_state *state)
1324 {
1325 	struct drm_mode_config *config = &state->dev->mode_config;
1326 	int ret;
1327 
1328 	ret = drm_atomic_check_only(state);
1329 	if (ret)
1330 		return ret;
1331 
1332 	DRM_DEBUG_ATOMIC("commiting %p asynchronously\n", state);
1333 
1334 	return config->funcs->atomic_commit(state->dev, state, true);
1335 }
1336 EXPORT_SYMBOL(drm_atomic_async_commit);
1337 
1338 /*
1339  * The big monstor ioctl
1340  */
1341 
1342 static struct drm_pending_vblank_event *create_vblank_event(
1343 		struct drm_device *dev, struct drm_file *file_priv, uint64_t user_data)
1344 {
1345 	struct drm_pending_vblank_event *e = NULL;
1346 	unsigned long flags;
1347 
1348 	spin_lock_irqsave(&dev->event_lock, flags);
1349 	if (file_priv->event_space < sizeof e->event) {
1350 		spin_unlock_irqrestore(&dev->event_lock, flags);
1351 		goto out;
1352 	}
1353 	file_priv->event_space -= sizeof e->event;
1354 	spin_unlock_irqrestore(&dev->event_lock, flags);
1355 
1356 	e = kzalloc(sizeof *e, GFP_KERNEL);
1357 	if (e == NULL) {
1358 		spin_lock_irqsave(&dev->event_lock, flags);
1359 		file_priv->event_space += sizeof e->event;
1360 		spin_unlock_irqrestore(&dev->event_lock, flags);
1361 		goto out;
1362 	}
1363 
1364 	e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
1365 	e->event.base.length = sizeof e->event;
1366 	e->event.user_data = user_data;
1367 	e->base.event = &e->event.base;
1368 	e->base.file_priv = file_priv;
1369 	e->base.destroy = (void (*) (struct drm_pending_event *)) kfree;
1370 
1371 out:
1372 	return e;
1373 }
1374 
1375 static void destroy_vblank_event(struct drm_device *dev,
1376 		struct drm_file *file_priv, struct drm_pending_vblank_event *e)
1377 {
1378 	unsigned long flags;
1379 
1380 	spin_lock_irqsave(&dev->event_lock, flags);
1381 	file_priv->event_space += sizeof e->event;
1382 	spin_unlock_irqrestore(&dev->event_lock, flags);
1383 	kfree(e);
1384 }
1385 
1386 static int atomic_set_prop(struct drm_atomic_state *state,
1387 		struct drm_mode_object *obj, struct drm_property *prop,
1388 		uint64_t prop_value)
1389 {
1390 	struct drm_mode_object *ref;
1391 	int ret;
1392 
1393 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
1394 		return -EINVAL;
1395 
1396 	switch (obj->type) {
1397 	case DRM_MODE_OBJECT_CONNECTOR: {
1398 		struct drm_connector *connector = obj_to_connector(obj);
1399 		struct drm_connector_state *connector_state;
1400 
1401 		connector_state = drm_atomic_get_connector_state(state, connector);
1402 		if (IS_ERR(connector_state)) {
1403 			ret = PTR_ERR(connector_state);
1404 			break;
1405 		}
1406 
1407 		ret = drm_atomic_connector_set_property(connector,
1408 				connector_state, prop, prop_value);
1409 		break;
1410 	}
1411 	case DRM_MODE_OBJECT_CRTC: {
1412 		struct drm_crtc *crtc = obj_to_crtc(obj);
1413 		struct drm_crtc_state *crtc_state;
1414 
1415 		crtc_state = drm_atomic_get_crtc_state(state, crtc);
1416 		if (IS_ERR(crtc_state)) {
1417 			ret = PTR_ERR(crtc_state);
1418 			break;
1419 		}
1420 
1421 		ret = drm_atomic_crtc_set_property(crtc,
1422 				crtc_state, prop, prop_value);
1423 		break;
1424 	}
1425 	case DRM_MODE_OBJECT_PLANE: {
1426 		struct drm_plane *plane = obj_to_plane(obj);
1427 		struct drm_plane_state *plane_state;
1428 
1429 		plane_state = drm_atomic_get_plane_state(state, plane);
1430 		if (IS_ERR(plane_state)) {
1431 			ret = PTR_ERR(plane_state);
1432 			break;
1433 		}
1434 
1435 		ret = drm_atomic_plane_set_property(plane,
1436 				plane_state, prop, prop_value);
1437 		break;
1438 	}
1439 	default:
1440 		ret = -EINVAL;
1441 		break;
1442 	}
1443 
1444 	drm_property_change_valid_put(prop, ref);
1445 	return ret;
1446 }
1447 
1448 /**
1449  * drm_atomic_clean_old_fb -- Unset old_fb pointers and set plane->fb pointers.
1450  *
1451  * @dev: drm device to check.
1452  * @plane_mask: plane mask for planes that were updated.
1453  * @ret: return value, can be -EDEADLK for a retry.
1454  *
1455  * Before doing an update plane->old_fb is set to plane->fb,
1456  * but before dropping the locks old_fb needs to be set to NULL
1457  * and plane->fb updated. This is a common operation for each
1458  * atomic update, so this call is split off as a helper.
1459  */
1460 void drm_atomic_clean_old_fb(struct drm_device *dev,
1461 			     unsigned plane_mask,
1462 			     int ret)
1463 {
1464 	struct drm_plane *plane;
1465 
1466 	/* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
1467 	 * locks (ie. while it is still safe to deref plane->state).  We
1468 	 * need to do this here because the driver entry points cannot
1469 	 * distinguish between legacy and atomic ioctls.
1470 	 */
1471 	drm_for_each_plane_mask(plane, dev, plane_mask) {
1472 		if (ret == 0) {
1473 			struct drm_framebuffer *new_fb = plane->state->fb;
1474 			if (new_fb)
1475 				drm_framebuffer_reference(new_fb);
1476 			plane->fb = new_fb;
1477 			plane->crtc = plane->state->crtc;
1478 
1479 			if (plane->old_fb)
1480 				drm_framebuffer_unreference(plane->old_fb);
1481 		}
1482 		plane->old_fb = NULL;
1483 	}
1484 }
1485 EXPORT_SYMBOL(drm_atomic_clean_old_fb);
1486 
1487 int drm_mode_atomic_ioctl(struct drm_device *dev,
1488 			  void *data, struct drm_file *file_priv)
1489 {
1490 	struct drm_mode_atomic *arg = data;
1491 	uint32_t __user *objs_ptr = (uint32_t __user *)(unsigned long)(arg->objs_ptr);
1492 	uint32_t __user *count_props_ptr = (uint32_t __user *)(unsigned long)(arg->count_props_ptr);
1493 	uint32_t __user *props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr);
1494 	uint64_t __user *prop_values_ptr = (uint64_t __user *)(unsigned long)(arg->prop_values_ptr);
1495 	unsigned int copied_objs, copied_props;
1496 	struct drm_atomic_state *state;
1497 	struct drm_modeset_acquire_ctx ctx;
1498 	struct drm_plane *plane;
1499 	struct drm_crtc *crtc;
1500 	struct drm_crtc_state *crtc_state;
1501 	unsigned plane_mask;
1502 	int ret = 0;
1503 	unsigned int i, j;
1504 
1505 	/* disallow for drivers not supporting atomic: */
1506 	if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
1507 		return -EINVAL;
1508 
1509 	/* disallow for userspace that has not enabled atomic cap (even
1510 	 * though this may be a bit overkill, since legacy userspace
1511 	 * wouldn't know how to call this ioctl)
1512 	 */
1513 	if (!file_priv->atomic)
1514 		return -EINVAL;
1515 
1516 	if (arg->flags & ~DRM_MODE_ATOMIC_FLAGS)
1517 		return -EINVAL;
1518 
1519 	if (arg->reserved)
1520 		return -EINVAL;
1521 
1522 	if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) &&
1523 			!dev->mode_config.async_page_flip)
1524 		return -EINVAL;
1525 
1526 	/* can't test and expect an event at the same time. */
1527 	if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) &&
1528 			(arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
1529 		return -EINVAL;
1530 
1531 	drm_modeset_acquire_init(&ctx, 0);
1532 
1533 	state = drm_atomic_state_alloc(dev);
1534 	if (!state)
1535 		return -ENOMEM;
1536 
1537 	state->acquire_ctx = &ctx;
1538 	state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
1539 
1540 retry:
1541 	plane_mask = 0;
1542 	copied_objs = 0;
1543 	copied_props = 0;
1544 
1545 	for (i = 0; i < arg->count_objs; i++) {
1546 		uint32_t obj_id, count_props;
1547 		struct drm_mode_object *obj;
1548 
1549 		if (get_user(obj_id, objs_ptr + copied_objs)) {
1550 			ret = -EFAULT;
1551 			goto out;
1552 		}
1553 
1554 		obj = drm_mode_object_find(dev, obj_id, DRM_MODE_OBJECT_ANY);
1555 		if (!obj || !obj->properties) {
1556 			ret = -ENOENT;
1557 			goto out;
1558 		}
1559 
1560 		if (get_user(count_props, count_props_ptr + copied_objs)) {
1561 			ret = -EFAULT;
1562 			goto out;
1563 		}
1564 
1565 		copied_objs++;
1566 
1567 		for (j = 0; j < count_props; j++) {
1568 			uint32_t prop_id;
1569 			uint64_t prop_value;
1570 			struct drm_property *prop;
1571 
1572 			if (get_user(prop_id, props_ptr + copied_props)) {
1573 				ret = -EFAULT;
1574 				goto out;
1575 			}
1576 
1577 			prop = drm_property_find(dev, prop_id);
1578 			if (!prop) {
1579 				ret = -ENOENT;
1580 				goto out;
1581 			}
1582 
1583 			if (copy_from_user(&prop_value,
1584 					   prop_values_ptr + copied_props,
1585 					   sizeof(prop_value))) {
1586 				ret = -EFAULT;
1587 				goto out;
1588 			}
1589 
1590 			ret = atomic_set_prop(state, obj, prop, prop_value);
1591 			if (ret)
1592 				goto out;
1593 
1594 			copied_props++;
1595 		}
1596 
1597 		if (obj->type == DRM_MODE_OBJECT_PLANE && count_props &&
1598 		    !(arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)) {
1599 			plane = obj_to_plane(obj);
1600 			plane_mask |= (1 << drm_plane_index(plane));
1601 			plane->old_fb = plane->fb;
1602 		}
1603 	}
1604 
1605 	if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1606 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1607 			struct drm_pending_vblank_event *e;
1608 
1609 			e = create_vblank_event(dev, file_priv, arg->user_data);
1610 			if (!e) {
1611 				ret = -ENOMEM;
1612 				goto out;
1613 			}
1614 
1615 			crtc_state->event = e;
1616 		}
1617 	}
1618 
1619 	if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
1620 		/*
1621 		 * Unlike commit, check_only does not clean up state.
1622 		 * Below we call drm_atomic_state_free for it.
1623 		 */
1624 		ret = drm_atomic_check_only(state);
1625 	} else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
1626 		ret = drm_atomic_async_commit(state);
1627 	} else {
1628 		ret = drm_atomic_commit(state);
1629 	}
1630 
1631 out:
1632 	drm_atomic_clean_old_fb(dev, plane_mask, ret);
1633 
1634 	if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1635 		/*
1636 		 * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
1637 		 * if they weren't, this code should be called on success
1638 		 * for TEST_ONLY too.
1639 		 */
1640 
1641 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1642 			if (!crtc_state->event)
1643 				continue;
1644 
1645 			destroy_vblank_event(dev, file_priv,
1646 					     crtc_state->event);
1647 		}
1648 	}
1649 
1650 	if (ret == -EDEADLK) {
1651 		drm_atomic_state_clear(state);
1652 		drm_modeset_backoff(&ctx);
1653 		goto retry;
1654 	}
1655 
1656 	if (ret || arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)
1657 		drm_atomic_state_free(state);
1658 
1659 	drm_modeset_drop_locks(&ctx);
1660 	drm_modeset_acquire_fini(&ctx);
1661 
1662 	return ret;
1663 }
1664