xref: /dragonfly/sys/dev/drm/drm_atomic.c (revision 59b0b316)
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 <uapi_drm/drm_mode.h>
32 #include <drm/drm_plane_helper.h>
33 
34 #include "drm_crtc_internal.h"
35 
36 /**
37  * drm_atomic_state_default_release -
38  * release memory initialized by drm_atomic_state_init
39  * @state: atomic state
40  *
41  * Free all the memory allocated by drm_atomic_state_init.
42  * This is useful for drivers that subclass the atomic state.
43  */
44 void drm_atomic_state_default_release(struct drm_atomic_state *state)
45 {
46 	kfree(state->connectors);
47 	kfree(state->connector_states);
48 	kfree(state->crtcs);
49 	kfree(state->crtc_states);
50 	kfree(state->planes);
51 	kfree(state->plane_states);
52 }
53 EXPORT_SYMBOL(drm_atomic_state_default_release);
54 
55 /**
56  * drm_atomic_state_init - init new atomic state
57  * @dev: DRM device
58  * @state: atomic state
59  *
60  * Default implementation for filling in a new atomic state.
61  * This is useful for drivers that subclass the atomic state.
62  */
63 int
64 drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
65 {
66 	/* TODO legacy paths should maybe do a better job about
67 	 * setting this appropriately?
68 	 */
69 	state->allow_modeset = true;
70 
71 	state->crtcs = kcalloc(dev->mode_config.num_crtc,
72 			       sizeof(*state->crtcs), GFP_KERNEL);
73 	if (!state->crtcs)
74 		goto fail;
75 	state->crtc_states = kcalloc(dev->mode_config.num_crtc,
76 				     sizeof(*state->crtc_states), GFP_KERNEL);
77 	if (!state->crtc_states)
78 		goto fail;
79 	state->planes = kcalloc(dev->mode_config.num_total_plane,
80 				sizeof(*state->planes), GFP_KERNEL);
81 	if (!state->planes)
82 		goto fail;
83 	state->plane_states = kcalloc(dev->mode_config.num_total_plane,
84 				      sizeof(*state->plane_states), GFP_KERNEL);
85 	if (!state->plane_states)
86 		goto fail;
87 
88 	state->dev = dev;
89 
90 	DRM_DEBUG_ATOMIC("Allocated atomic state %p\n", state);
91 
92 	return 0;
93 fail:
94 	drm_atomic_state_default_release(state);
95 	return -ENOMEM;
96 }
97 EXPORT_SYMBOL(drm_atomic_state_init);
98 
99 /**
100  * drm_atomic_state_alloc - allocate atomic state
101  * @dev: DRM device
102  *
103  * This allocates an empty atomic state to track updates.
104  */
105 struct drm_atomic_state *
106 drm_atomic_state_alloc(struct drm_device *dev)
107 {
108 	struct drm_mode_config *config = &dev->mode_config;
109 	struct drm_atomic_state *state;
110 
111 	if (!config->funcs->atomic_state_alloc) {
112 		state = kzalloc(sizeof(*state), GFP_KERNEL);
113 		if (!state)
114 			return NULL;
115 		if (drm_atomic_state_init(dev, state) < 0) {
116 			kfree(state);
117 			return NULL;
118 		}
119 		return state;
120 	}
121 
122 	return config->funcs->atomic_state_alloc(dev);
123 }
124 EXPORT_SYMBOL(drm_atomic_state_alloc);
125 
126 /**
127  * drm_atomic_state_default_clear - clear base atomic state
128  * @state: atomic state
129  *
130  * Default implementation for clearing atomic state.
131  * This is useful for drivers that subclass the atomic state.
132  */
133 void drm_atomic_state_default_clear(struct drm_atomic_state *state)
134 {
135 	struct drm_device *dev = state->dev;
136 	struct drm_mode_config *config = &dev->mode_config;
137 	int i;
138 
139 	DRM_DEBUG_ATOMIC("Clearing atomic state %p\n", state);
140 
141 	for (i = 0; i < state->num_connector; i++) {
142 		struct drm_connector *connector = state->connectors[i];
143 
144 		if (!connector)
145 			continue;
146 
147 		connector->funcs->atomic_destroy_state(connector,
148 						       state->connector_states[i]);
149 		state->connectors[i] = NULL;
150 		state->connector_states[i] = NULL;
151 		drm_connector_unreference(connector);
152 	}
153 
154 	for (i = 0; i < config->num_crtc; i++) {
155 		struct drm_crtc *crtc = state->crtcs[i];
156 
157 		if (!crtc)
158 			continue;
159 
160 		crtc->funcs->atomic_destroy_state(crtc,
161 						  state->crtc_states[i]);
162 		state->crtcs[i] = NULL;
163 		state->crtc_states[i] = NULL;
164 	}
165 
166 	for (i = 0; i < config->num_total_plane; i++) {
167 		struct drm_plane *plane = state->planes[i];
168 
169 		if (!plane)
170 			continue;
171 
172 		plane->funcs->atomic_destroy_state(plane,
173 						   state->plane_states[i]);
174 		state->planes[i] = NULL;
175 		state->plane_states[i] = NULL;
176 	}
177 }
178 EXPORT_SYMBOL(drm_atomic_state_default_clear);
179 
180 /**
181  * drm_atomic_state_clear - clear state object
182  * @state: atomic state
183  *
184  * When the w/w mutex algorithm detects a deadlock we need to back off and drop
185  * all locks. So someone else could sneak in and change the current modeset
186  * configuration. Which means that all the state assembled in @state is no
187  * longer an atomic update to the current state, but to some arbitrary earlier
188  * state. Which could break assumptions the driver's ->atomic_check likely
189  * relies on.
190  *
191  * Hence we must clear all cached state and completely start over, using this
192  * function.
193  */
194 void drm_atomic_state_clear(struct drm_atomic_state *state)
195 {
196 	struct drm_device *dev = state->dev;
197 	struct drm_mode_config *config = &dev->mode_config;
198 
199 	if (config->funcs->atomic_state_clear)
200 		config->funcs->atomic_state_clear(state);
201 	else
202 		drm_atomic_state_default_clear(state);
203 }
204 EXPORT_SYMBOL(drm_atomic_state_clear);
205 
206 /**
207  * drm_atomic_state_free - free all memory for an atomic state
208  * @state: atomic state to deallocate
209  *
210  * This frees all memory associated with an atomic state, including all the
211  * per-object state for planes, crtcs and connectors.
212  */
213 void drm_atomic_state_free(struct drm_atomic_state *state)
214 {
215 	struct drm_device *dev;
216 	struct drm_mode_config *config;
217 
218 	if (!state)
219 		return;
220 
221 	dev = state->dev;
222 	config = &dev->mode_config;
223 
224 	drm_atomic_state_clear(state);
225 
226 	DRM_DEBUG_ATOMIC("Freeing atomic state %p\n", state);
227 
228 	if (config->funcs->atomic_state_free) {
229 		config->funcs->atomic_state_free(state);
230 	} else {
231 		drm_atomic_state_default_release(state);
232 		kfree(state);
233 	}
234 }
235 EXPORT_SYMBOL(drm_atomic_state_free);
236 
237 /**
238  * drm_atomic_get_crtc_state - get crtc state
239  * @state: global atomic state object
240  * @crtc: crtc to get state object for
241  *
242  * This function returns the crtc state for the given crtc, allocating it if
243  * needed. It will also grab the relevant crtc lock to make sure that the state
244  * is consistent.
245  *
246  * Returns:
247  *
248  * Either the allocated state or the error code encoded into the pointer. When
249  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
250  * entire atomic sequence must be restarted. All other errors are fatal.
251  */
252 struct drm_crtc_state *
253 drm_atomic_get_crtc_state(struct drm_atomic_state *state,
254 			  struct drm_crtc *crtc)
255 {
256 	int ret, index = drm_crtc_index(crtc);
257 	struct drm_crtc_state *crtc_state;
258 
259 	WARN_ON(!state->acquire_ctx);
260 
261 	crtc_state = drm_atomic_get_existing_crtc_state(state, crtc);
262 	if (crtc_state)
263 		return crtc_state;
264 
265 	ret = drm_modeset_lock(&crtc->mutex, state->acquire_ctx);
266 	if (ret)
267 		return ERR_PTR(ret);
268 
269 	crtc_state = crtc->funcs->atomic_duplicate_state(crtc);
270 	if (!crtc_state)
271 		return ERR_PTR(-ENOMEM);
272 
273 	state->crtc_states[index] = crtc_state;
274 	state->crtcs[index] = crtc;
275 	crtc_state->state = state;
276 
277 	DRM_DEBUG_ATOMIC("Added [CRTC:%d:%s] %p state to %p\n",
278 			 crtc->base.id, crtc->name, crtc_state, state);
279 
280 	return crtc_state;
281 }
282 EXPORT_SYMBOL(drm_atomic_get_crtc_state);
283 
284 /**
285  * drm_atomic_set_mode_for_crtc - set mode for CRTC
286  * @state: the CRTC whose incoming state to update
287  * @mode: kernel-internal mode to use for the CRTC, or NULL to disable
288  *
289  * Set a mode (originating from the kernel) on the desired CRTC state. Does
290  * not change any other state properties, including enable, active, or
291  * mode_changed.
292  *
293  * RETURNS:
294  * Zero on success, error code on failure. Cannot return -EDEADLK.
295  */
296 int drm_atomic_set_mode_for_crtc(struct drm_crtc_state *state,
297 				 struct drm_display_mode *mode)
298 {
299 	struct drm_mode_modeinfo umode;
300 
301 	/* Early return for no change. */
302 	if (mode && memcmp(&state->mode, mode, sizeof(*mode)) == 0)
303 		return 0;
304 
305 	drm_property_unreference_blob(state->mode_blob);
306 	state->mode_blob = NULL;
307 
308 	if (mode) {
309 		drm_mode_convert_to_umode(&umode, mode);
310 		state->mode_blob =
311 			drm_property_create_blob(state->crtc->dev,
312 		                                 sizeof(umode),
313 		                                 &umode);
314 		if (IS_ERR(state->mode_blob))
315 			return PTR_ERR(state->mode_blob);
316 
317 		drm_mode_copy(&state->mode, mode);
318 		state->enable = true;
319 		DRM_DEBUG_ATOMIC("Set [MODE:%s] for CRTC state %p\n",
320 				 mode->name, state);
321 	} else {
322 		memset(&state->mode, 0, sizeof(state->mode));
323 		state->enable = false;
324 		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
325 				 state);
326 	}
327 
328 	return 0;
329 }
330 EXPORT_SYMBOL(drm_atomic_set_mode_for_crtc);
331 
332 /**
333  * drm_atomic_set_mode_prop_for_crtc - set mode for CRTC
334  * @state: the CRTC whose incoming state to update
335  * @blob: pointer to blob property to use for mode
336  *
337  * Set a mode (originating from a blob property) on the desired CRTC state.
338  * This function will take a reference on the blob property for the CRTC state,
339  * and release the reference held on the state's existing mode property, if any
340  * was set.
341  *
342  * RETURNS:
343  * Zero on success, error code on failure. Cannot return -EDEADLK.
344  */
345 int drm_atomic_set_mode_prop_for_crtc(struct drm_crtc_state *state,
346                                       struct drm_property_blob *blob)
347 {
348 	if (blob == state->mode_blob)
349 		return 0;
350 
351 	drm_property_unreference_blob(state->mode_blob);
352 	state->mode_blob = NULL;
353 
354 	memset(&state->mode, 0, sizeof(state->mode));
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 		state->enable = false;
369 		DRM_DEBUG_ATOMIC("Set [NOMODE] for CRTC state %p\n",
370 				 state);
371 	}
372 
373 	return 0;
374 }
375 EXPORT_SYMBOL(drm_atomic_set_mode_prop_for_crtc);
376 
377 /**
378  * drm_atomic_replace_property_blob - replace a blob property
379  * @blob: a pointer to the member blob to be replaced
380  * @new_blob: the new blob to replace with
381  * @replaced: whether the blob has been replaced
382  *
383  * RETURNS:
384  * Zero on success, error code on failure
385  */
386 static void
387 drm_atomic_replace_property_blob(struct drm_property_blob **blob,
388 				 struct drm_property_blob *new_blob,
389 				 bool *replaced)
390 {
391 	struct drm_property_blob *old_blob = *blob;
392 
393 	if (old_blob == new_blob)
394 		return;
395 
396 	if (old_blob)
397 		drm_property_unreference_blob(old_blob);
398 	if (new_blob)
399 		drm_property_reference_blob(new_blob);
400 	*blob = new_blob;
401 	*replaced = true;
402 
403 	return;
404 }
405 
406 static int
407 drm_atomic_replace_property_blob_from_id(struct drm_crtc *crtc,
408 					 struct drm_property_blob **blob,
409 					 uint64_t blob_id,
410 					 ssize_t expected_size,
411 					 bool *replaced)
412 {
413 	struct drm_device *dev = crtc->dev;
414 	struct drm_property_blob *new_blob = NULL;
415 
416 	if (blob_id != 0) {
417 		new_blob = drm_property_lookup_blob(dev, blob_id);
418 		if (new_blob == NULL)
419 			return -EINVAL;
420 		if (expected_size > 0 && expected_size != new_blob->length)
421 			return -EINVAL;
422 	}
423 
424 	drm_atomic_replace_property_blob(blob, new_blob, replaced);
425 
426 	return 0;
427 }
428 
429 /**
430  * drm_atomic_crtc_set_property - set property on CRTC
431  * @crtc: the drm CRTC to set a property on
432  * @state: the state object to update with the new property value
433  * @property: the property to set
434  * @val: the new property value
435  *
436  * Use this instead of calling crtc->atomic_set_property directly.
437  * This function handles generic/core properties and calls out to
438  * driver's ->atomic_set_property() for driver properties.  To ensure
439  * consistent behavior you must call this function rather than the
440  * driver hook directly.
441  *
442  * RETURNS:
443  * Zero on success, error code on failure
444  */
445 int drm_atomic_crtc_set_property(struct drm_crtc *crtc,
446 		struct drm_crtc_state *state, struct drm_property *property,
447 		uint64_t val)
448 {
449 	struct drm_device *dev = crtc->dev;
450 	struct drm_mode_config *config = &dev->mode_config;
451 	bool replaced = false;
452 	int ret;
453 
454 	if (property == config->prop_active)
455 		state->active = val;
456 	else if (property == config->prop_mode_id) {
457 		struct drm_property_blob *mode =
458 			drm_property_lookup_blob(dev, val);
459 		ret = drm_atomic_set_mode_prop_for_crtc(state, mode);
460 		drm_property_unreference_blob(mode);
461 		return ret;
462 	} else if (property == config->degamma_lut_property) {
463 		ret = drm_atomic_replace_property_blob_from_id(crtc,
464 					&state->degamma_lut,
465 					val,
466 					-1,
467 					&replaced);
468 		state->color_mgmt_changed |= replaced;
469 		return ret;
470 	} else if (property == config->ctm_property) {
471 		ret = drm_atomic_replace_property_blob_from_id(crtc,
472 					&state->ctm,
473 					val,
474 					sizeof(struct drm_color_ctm),
475 					&replaced);
476 		state->color_mgmt_changed |= replaced;
477 		return ret;
478 	} else if (property == config->gamma_lut_property) {
479 		ret = drm_atomic_replace_property_blob_from_id(crtc,
480 					&state->gamma_lut,
481 					val,
482 					-1,
483 					&replaced);
484 		state->color_mgmt_changed |= replaced;
485 		return ret;
486 	} else if (crtc->funcs->atomic_set_property)
487 		return crtc->funcs->atomic_set_property(crtc, state, property, val);
488 	else
489 		return -EINVAL;
490 
491 	return 0;
492 }
493 EXPORT_SYMBOL(drm_atomic_crtc_set_property);
494 
495 /**
496  * drm_atomic_crtc_get_property - get property value from CRTC state
497  * @crtc: the drm CRTC to set a property on
498  * @state: the state object to get the property value from
499  * @property: the property to set
500  * @val: return location for the property value
501  *
502  * This function handles generic/core properties and calls out to
503  * driver's ->atomic_get_property() for driver properties.  To ensure
504  * consistent behavior you must call this function rather than the
505  * driver hook directly.
506  *
507  * RETURNS:
508  * Zero on success, error code on failure
509  */
510 static int
511 drm_atomic_crtc_get_property(struct drm_crtc *crtc,
512 		const struct drm_crtc_state *state,
513 		struct drm_property *property, uint64_t *val)
514 {
515 	struct drm_device *dev = crtc->dev;
516 	struct drm_mode_config *config = &dev->mode_config;
517 
518 	if (property == config->prop_active)
519 		*val = state->active;
520 	else if (property == config->prop_mode_id)
521 		*val = (state->mode_blob) ? state->mode_blob->base.id : 0;
522 	else if (property == config->degamma_lut_property)
523 		*val = (state->degamma_lut) ? state->degamma_lut->base.id : 0;
524 	else if (property == config->ctm_property)
525 		*val = (state->ctm) ? state->ctm->base.id : 0;
526 	else if (property == config->gamma_lut_property)
527 		*val = (state->gamma_lut) ? state->gamma_lut->base.id : 0;
528 	else if (crtc->funcs->atomic_get_property)
529 		return crtc->funcs->atomic_get_property(crtc, state, property, val);
530 	else
531 		return -EINVAL;
532 
533 	return 0;
534 }
535 
536 /**
537  * drm_atomic_crtc_check - check crtc state
538  * @crtc: crtc to check
539  * @state: crtc state to check
540  *
541  * Provides core sanity checks for crtc state.
542  *
543  * RETURNS:
544  * Zero on success, error code on failure
545  */
546 static int drm_atomic_crtc_check(struct drm_crtc *crtc,
547 		struct drm_crtc_state *state)
548 {
549 	/* NOTE: we explicitly don't enforce constraints such as primary
550 	 * layer covering entire screen, since that is something we want
551 	 * to allow (on hw that supports it).  For hw that does not, it
552 	 * should be checked in driver's crtc->atomic_check() vfunc.
553 	 *
554 	 * TODO: Add generic modeset state checks once we support those.
555 	 */
556 
557 	if (state->active && !state->enable) {
558 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] active without enabled\n",
559 				 crtc->base.id, crtc->name);
560 		return -EINVAL;
561 	}
562 
563 	/* The state->enable vs. state->mode_blob checks can be WARN_ON,
564 	 * as this is a kernel-internal detail that userspace should never
565 	 * be able to trigger. */
566 	if (drm_core_check_feature(crtc->dev, DRIVER_ATOMIC) &&
567 	    WARN_ON(state->enable && !state->mode_blob)) {
568 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] enabled without mode blob\n",
569 				 crtc->base.id, crtc->name);
570 		return -EINVAL;
571 	}
572 
573 	if (drm_core_check_feature(crtc->dev, DRIVER_ATOMIC) &&
574 	    WARN_ON(!state->enable && state->mode_blob)) {
575 		DRM_DEBUG_ATOMIC("[CRTC:%d:%s] disabled with mode blob\n",
576 				 crtc->base.id, crtc->name);
577 		return -EINVAL;
578 	}
579 
580 	/*
581 	 * Reject event generation for when a CRTC is off and stays off.
582 	 * It wouldn't be hard to implement this, but userspace has a track
583 	 * record of happily burning through 100% cpu (or worse, crash) when the
584 	 * display pipe is suspended. To avoid all that fun just reject updates
585 	 * that ask for events since likely that indicates a bug in the
586 	 * compositor's drawing loop. This is consistent with the vblank IOCTL
587 	 * and legacy page_flip IOCTL which also reject service on a disabled
588 	 * pipe.
589 	 */
590 	if (state->event && !state->active && !crtc->state->active) {
591 		DRM_DEBUG_ATOMIC("[CRTC:%d] requesting event but off\n",
592 				 crtc->base.id);
593 		return -EINVAL;
594 	}
595 
596 	return 0;
597 }
598 
599 /**
600  * drm_atomic_get_plane_state - get plane state
601  * @state: global atomic state object
602  * @plane: plane to get state object for
603  *
604  * This function returns the plane state for the given plane, allocating it if
605  * needed. It will also grab the relevant plane lock to make sure that the state
606  * is consistent.
607  *
608  * Returns:
609  *
610  * Either the allocated state or the error code encoded into the pointer. When
611  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
612  * entire atomic sequence must be restarted. All other errors are fatal.
613  */
614 struct drm_plane_state *
615 drm_atomic_get_plane_state(struct drm_atomic_state *state,
616 			  struct drm_plane *plane)
617 {
618 	int ret, index = drm_plane_index(plane);
619 	struct drm_plane_state *plane_state;
620 
621 	WARN_ON(!state->acquire_ctx);
622 
623 	plane_state = drm_atomic_get_existing_plane_state(state, plane);
624 	if (plane_state)
625 		return plane_state;
626 
627 	ret = drm_modeset_lock(&plane->mutex, state->acquire_ctx);
628 	if (ret)
629 		return ERR_PTR(ret);
630 
631 	plane_state = plane->funcs->atomic_duplicate_state(plane);
632 	if (!plane_state)
633 		return ERR_PTR(-ENOMEM);
634 
635 	state->plane_states[index] = plane_state;
636 	state->planes[index] = plane;
637 	plane_state->state = state;
638 
639 	DRM_DEBUG_ATOMIC("Added [PLANE:%d:%s] %p state to %p\n",
640 			 plane->base.id, plane->name, plane_state, state);
641 
642 	if (plane_state->crtc) {
643 		struct drm_crtc_state *crtc_state;
644 
645 		crtc_state = drm_atomic_get_crtc_state(state,
646 						       plane_state->crtc);
647 		if (IS_ERR(crtc_state))
648 			return ERR_CAST(crtc_state);
649 	}
650 
651 	return plane_state;
652 }
653 EXPORT_SYMBOL(drm_atomic_get_plane_state);
654 
655 /**
656  * drm_atomic_plane_set_property - set property on plane
657  * @plane: the drm plane to set a property on
658  * @state: the state object to update with the new property value
659  * @property: the property to set
660  * @val: the new property value
661  *
662  * Use this instead of calling plane->atomic_set_property directly.
663  * This function handles generic/core properties and calls out to
664  * driver's ->atomic_set_property() for driver properties.  To ensure
665  * consistent behavior you must call this function rather than the
666  * driver hook directly.
667  *
668  * RETURNS:
669  * Zero on success, error code on failure
670  */
671 int drm_atomic_plane_set_property(struct drm_plane *plane,
672 		struct drm_plane_state *state, struct drm_property *property,
673 		uint64_t val)
674 {
675 	struct drm_device *dev = plane->dev;
676 	struct drm_mode_config *config = &dev->mode_config;
677 
678 	if (property == config->prop_fb_id) {
679 		struct drm_framebuffer *fb = drm_framebuffer_lookup(dev, val);
680 		drm_atomic_set_fb_for_plane(state, fb);
681 		if (fb)
682 			drm_framebuffer_unreference(fb);
683 	} else if (property == config->prop_crtc_id) {
684 		struct drm_crtc *crtc = drm_crtc_find(dev, val);
685 		return drm_atomic_set_crtc_for_plane(state, crtc);
686 	} else if (property == config->prop_crtc_x) {
687 		state->crtc_x = U642I64(val);
688 	} else if (property == config->prop_crtc_y) {
689 		state->crtc_y = U642I64(val);
690 	} else if (property == config->prop_crtc_w) {
691 		state->crtc_w = val;
692 	} else if (property == config->prop_crtc_h) {
693 		state->crtc_h = val;
694 	} else if (property == config->prop_src_x) {
695 		state->src_x = val;
696 	} else if (property == config->prop_src_y) {
697 		state->src_y = val;
698 	} else if (property == config->prop_src_w) {
699 		state->src_w = val;
700 	} else if (property == config->prop_src_h) {
701 		state->src_h = val;
702 	} else if (property == config->rotation_property) {
703 		state->rotation = val;
704 	} else if (plane->funcs->atomic_set_property) {
705 		return plane->funcs->atomic_set_property(plane, state,
706 				property, val);
707 	} else {
708 		return -EINVAL;
709 	}
710 
711 	return 0;
712 }
713 EXPORT_SYMBOL(drm_atomic_plane_set_property);
714 
715 /**
716  * drm_atomic_plane_get_property - get property value from plane state
717  * @plane: the drm plane to set a property on
718  * @state: the state object to get the property value from
719  * @property: the property to set
720  * @val: return location for the property value
721  *
722  * This function handles generic/core properties and calls out to
723  * driver's ->atomic_get_property() for driver properties.  To ensure
724  * consistent behavior you must call this function rather than the
725  * driver hook directly.
726  *
727  * RETURNS:
728  * Zero on success, error code on failure
729  */
730 static int
731 drm_atomic_plane_get_property(struct drm_plane *plane,
732 		const struct drm_plane_state *state,
733 		struct drm_property *property, uint64_t *val)
734 {
735 	struct drm_device *dev = plane->dev;
736 	struct drm_mode_config *config = &dev->mode_config;
737 
738 	if (property == config->prop_fb_id) {
739 		*val = (state->fb) ? state->fb->base.id : 0;
740 	} else if (property == config->prop_crtc_id) {
741 		*val = (state->crtc) ? state->crtc->base.id : 0;
742 	} else if (property == config->prop_crtc_x) {
743 		*val = I642U64(state->crtc_x);
744 	} else if (property == config->prop_crtc_y) {
745 		*val = I642U64(state->crtc_y);
746 	} else if (property == config->prop_crtc_w) {
747 		*val = state->crtc_w;
748 	} else if (property == config->prop_crtc_h) {
749 		*val = state->crtc_h;
750 	} else if (property == config->prop_src_x) {
751 		*val = state->src_x;
752 	} else if (property == config->prop_src_y) {
753 		*val = state->src_y;
754 	} else if (property == config->prop_src_w) {
755 		*val = state->src_w;
756 	} else if (property == config->prop_src_h) {
757 		*val = state->src_h;
758 	} else if (property == config->rotation_property) {
759 		*val = state->rotation;
760 	} else if (plane->funcs->atomic_get_property) {
761 		return plane->funcs->atomic_get_property(plane, state, property, val);
762 	} else {
763 		return -EINVAL;
764 	}
765 
766 	return 0;
767 }
768 
769 static bool
770 plane_switching_crtc(struct drm_atomic_state *state,
771 		     struct drm_plane *plane,
772 		     struct drm_plane_state *plane_state)
773 {
774 	if (!plane->state->crtc || !plane_state->crtc)
775 		return false;
776 
777 	if (plane->state->crtc == plane_state->crtc)
778 		return false;
779 
780 	/* This could be refined, but currently there's no helper or driver code
781 	 * to implement direct switching of active planes nor userspace to take
782 	 * advantage of more direct plane switching without the intermediate
783 	 * full OFF state.
784 	 */
785 	return true;
786 }
787 
788 /**
789  * drm_atomic_plane_check - check plane state
790  * @plane: plane to check
791  * @state: plane state to check
792  *
793  * Provides core sanity checks for plane state.
794  *
795  * RETURNS:
796  * Zero on success, error code on failure
797  */
798 static int drm_atomic_plane_check(struct drm_plane *plane,
799 		struct drm_plane_state *state)
800 {
801 	unsigned int fb_width, fb_height;
802 	int ret;
803 
804 	/* either *both* CRTC and FB must be set, or neither */
805 	if (WARN_ON(state->crtc && !state->fb)) {
806 		DRM_DEBUG_ATOMIC("CRTC set but no FB\n");
807 		return -EINVAL;
808 	} else if (WARN_ON(state->fb && !state->crtc)) {
809 		DRM_DEBUG_ATOMIC("FB set but no CRTC\n");
810 		return -EINVAL;
811 	}
812 
813 	/* if disabled, we don't care about the rest of the state: */
814 	if (!state->crtc)
815 		return 0;
816 
817 	/* Check whether this plane is usable on this CRTC */
818 	if (!(plane->possible_crtcs & drm_crtc_mask(state->crtc))) {
819 		DRM_DEBUG_ATOMIC("Invalid crtc for plane\n");
820 		return -EINVAL;
821 	}
822 
823 	/* Check whether this plane supports the fb pixel format. */
824 	ret = drm_plane_check_pixel_format(plane, state->fb->pixel_format);
825 	if (ret) {
826 		DRM_DEBUG_ATOMIC("Invalid pixel format %s\n",
827 				 drm_get_format_name(state->fb->pixel_format));
828 		return ret;
829 	}
830 
831 	/* Give drivers some help against integer overflows */
832 	if (state->crtc_w > INT_MAX ||
833 	    state->crtc_x > INT_MAX - (int32_t) state->crtc_w ||
834 	    state->crtc_h > INT_MAX ||
835 	    state->crtc_y > INT_MAX - (int32_t) state->crtc_h) {
836 		DRM_DEBUG_ATOMIC("Invalid CRTC coordinates %ux%u+%d+%d\n",
837 				 state->crtc_w, state->crtc_h,
838 				 state->crtc_x, state->crtc_y);
839 		return -ERANGE;
840 	}
841 
842 	fb_width = state->fb->width << 16;
843 	fb_height = state->fb->height << 16;
844 
845 	/* Make sure source coordinates are inside the fb. */
846 	if (state->src_w > fb_width ||
847 	    state->src_x > fb_width - state->src_w ||
848 	    state->src_h > fb_height ||
849 	    state->src_y > fb_height - state->src_h) {
850 		DRM_DEBUG_ATOMIC("Invalid source coordinates "
851 				 "%u.%06ux%u.%06u+%u.%06u+%u.%06u\n",
852 				 state->src_w >> 16, ((state->src_w & 0xffff) * 15625) >> 10,
853 				 state->src_h >> 16, ((state->src_h & 0xffff) * 15625) >> 10,
854 				 state->src_x >> 16, ((state->src_x & 0xffff) * 15625) >> 10,
855 				 state->src_y >> 16, ((state->src_y & 0xffff) * 15625) >> 10);
856 		return -ENOSPC;
857 	}
858 
859 	if (plane_switching_crtc(state->state, plane, state)) {
860 		DRM_DEBUG_ATOMIC("[PLANE:%d:%s] switching CRTC directly\n",
861 				 plane->base.id, plane->name);
862 		return -EINVAL;
863 	}
864 
865 	return 0;
866 }
867 
868 /**
869  * drm_atomic_get_connector_state - get connector state
870  * @state: global atomic state object
871  * @connector: connector to get state object for
872  *
873  * This function returns the connector state for the given connector,
874  * allocating it if needed. It will also grab the relevant connector lock to
875  * make sure that the state is consistent.
876  *
877  * Returns:
878  *
879  * Either the allocated state or the error code encoded into the pointer. When
880  * the error is EDEADLK then the w/w mutex code has detected a deadlock and the
881  * entire atomic sequence must be restarted. All other errors are fatal.
882  */
883 struct drm_connector_state *
884 drm_atomic_get_connector_state(struct drm_atomic_state *state,
885 			  struct drm_connector *connector)
886 {
887 	int ret, index;
888 	struct drm_mode_config *config = &connector->dev->mode_config;
889 	struct drm_connector_state *connector_state;
890 
891 	WARN_ON(!state->acquire_ctx);
892 
893 	ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx);
894 	if (ret)
895 		return ERR_PTR(ret);
896 
897 	index = drm_connector_index(connector);
898 
899 	if (index >= state->num_connector) {
900 		struct drm_connector **c;
901 		struct drm_connector_state **cs;
902 		int alloc = max(index + 1, config->num_connector);
903 
904 		c = krealloc(state->connectors, alloc * sizeof(*state->connectors), M_DRM, M_WAITOK);
905 		if (!c)
906 			return ERR_PTR(-ENOMEM);
907 
908 		state->connectors = c;
909 		memset(&state->connectors[state->num_connector], 0,
910 		       sizeof(*state->connectors) * (alloc - state->num_connector));
911 
912 		cs = krealloc(state->connector_states, alloc * sizeof(*state->connector_states), M_DRM, M_WAITOK);
913 		if (!cs)
914 			return ERR_PTR(-ENOMEM);
915 
916 		state->connector_states = cs;
917 		memset(&state->connector_states[state->num_connector], 0,
918 		       sizeof(*state->connector_states) * (alloc - state->num_connector));
919 		state->num_connector = alloc;
920 	}
921 
922 	if (state->connector_states[index])
923 		return state->connector_states[index];
924 
925 	connector_state = connector->funcs->atomic_duplicate_state(connector);
926 	if (!connector_state)
927 		return ERR_PTR(-ENOMEM);
928 
929 	drm_connector_reference(connector);
930 	state->connector_states[index] = connector_state;
931 	state->connectors[index] = connector;
932 	connector_state->state = state;
933 
934 	DRM_DEBUG_ATOMIC("Added [CONNECTOR:%d] %p state to %p\n",
935 			 connector->base.id, connector_state, state);
936 
937 	if (connector_state->crtc) {
938 		struct drm_crtc_state *crtc_state;
939 
940 		crtc_state = drm_atomic_get_crtc_state(state,
941 						       connector_state->crtc);
942 		if (IS_ERR(crtc_state))
943 			return ERR_CAST(crtc_state);
944 	}
945 
946 	return connector_state;
947 }
948 EXPORT_SYMBOL(drm_atomic_get_connector_state);
949 
950 /**
951  * drm_atomic_connector_set_property - set property on connector.
952  * @connector: the drm connector to set a property on
953  * @state: the state object to update with the new property value
954  * @property: the property to set
955  * @val: the new property value
956  *
957  * Use this instead of calling connector->atomic_set_property directly.
958  * This function handles generic/core properties and calls out to
959  * driver's ->atomic_set_property() for driver properties.  To ensure
960  * consistent behavior you must call this function rather than the
961  * driver hook directly.
962  *
963  * RETURNS:
964  * Zero on success, error code on failure
965  */
966 int drm_atomic_connector_set_property(struct drm_connector *connector,
967 		struct drm_connector_state *state, struct drm_property *property,
968 		uint64_t val)
969 {
970 	struct drm_device *dev = connector->dev;
971 	struct drm_mode_config *config = &dev->mode_config;
972 
973 	if (property == config->prop_crtc_id) {
974 		struct drm_crtc *crtc = drm_crtc_find(dev, val);
975 		return drm_atomic_set_crtc_for_connector(state, crtc);
976 	} else if (property == config->dpms_property) {
977 		/* setting DPMS property requires special handling, which
978 		 * is done in legacy setprop path for us.  Disallow (for
979 		 * now?) atomic writes to DPMS property:
980 		 */
981 		return -EINVAL;
982 	} else if (connector->funcs->atomic_set_property) {
983 		return connector->funcs->atomic_set_property(connector,
984 				state, property, val);
985 	} else {
986 		return -EINVAL;
987 	}
988 }
989 EXPORT_SYMBOL(drm_atomic_connector_set_property);
990 
991 /**
992  * drm_atomic_connector_get_property - get property value from connector state
993  * @connector: the drm connector to set a property on
994  * @state: the state object to get the property value from
995  * @property: the property to set
996  * @val: return location for the property value
997  *
998  * This function handles generic/core properties and calls out to
999  * driver's ->atomic_get_property() for driver properties.  To ensure
1000  * consistent behavior you must call this function rather than the
1001  * driver hook directly.
1002  *
1003  * RETURNS:
1004  * Zero on success, error code on failure
1005  */
1006 static int
1007 drm_atomic_connector_get_property(struct drm_connector *connector,
1008 		const struct drm_connector_state *state,
1009 		struct drm_property *property, uint64_t *val)
1010 {
1011 	struct drm_device *dev = connector->dev;
1012 	struct drm_mode_config *config = &dev->mode_config;
1013 
1014 	if (property == config->prop_crtc_id) {
1015 		*val = (state->crtc) ? state->crtc->base.id : 0;
1016 	} else if (property == config->dpms_property) {
1017 		*val = connector->dpms;
1018 	} else if (connector->funcs->atomic_get_property) {
1019 		return connector->funcs->atomic_get_property(connector,
1020 				state, property, val);
1021 	} else {
1022 		return -EINVAL;
1023 	}
1024 
1025 	return 0;
1026 }
1027 
1028 int drm_atomic_get_property(struct drm_mode_object *obj,
1029 		struct drm_property *property, uint64_t *val)
1030 {
1031 	struct drm_device *dev = property->dev;
1032 	int ret;
1033 
1034 	switch (obj->type) {
1035 	case DRM_MODE_OBJECT_CONNECTOR: {
1036 		struct drm_connector *connector = obj_to_connector(obj);
1037 		WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
1038 		ret = drm_atomic_connector_get_property(connector,
1039 				connector->state, property, val);
1040 		break;
1041 	}
1042 	case DRM_MODE_OBJECT_CRTC: {
1043 		struct drm_crtc *crtc = obj_to_crtc(obj);
1044 		WARN_ON(!drm_modeset_is_locked(&crtc->mutex));
1045 		ret = drm_atomic_crtc_get_property(crtc,
1046 				crtc->state, property, val);
1047 		break;
1048 	}
1049 	case DRM_MODE_OBJECT_PLANE: {
1050 		struct drm_plane *plane = obj_to_plane(obj);
1051 		WARN_ON(!drm_modeset_is_locked(&plane->mutex));
1052 		ret = drm_atomic_plane_get_property(plane,
1053 				plane->state, property, val);
1054 		break;
1055 	}
1056 	default:
1057 		ret = -EINVAL;
1058 		break;
1059 	}
1060 
1061 	return ret;
1062 }
1063 
1064 /**
1065  * drm_atomic_set_crtc_for_plane - set crtc for plane
1066  * @plane_state: the plane whose incoming state to update
1067  * @crtc: crtc to use for the plane
1068  *
1069  * Changing the assigned crtc for a plane requires us to grab the lock and state
1070  * for the new crtc, as needed. This function takes care of all these details
1071  * besides updating the pointer in the state object itself.
1072  *
1073  * Returns:
1074  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1075  * then the w/w mutex code has detected a deadlock and the entire atomic
1076  * sequence must be restarted. All other errors are fatal.
1077  */
1078 int
1079 drm_atomic_set_crtc_for_plane(struct drm_plane_state *plane_state,
1080 			      struct drm_crtc *crtc)
1081 {
1082 	struct drm_plane *plane = plane_state->plane;
1083 	struct drm_crtc_state *crtc_state;
1084 
1085 	if (plane_state->crtc) {
1086 		crtc_state = drm_atomic_get_crtc_state(plane_state->state,
1087 						       plane_state->crtc);
1088 		if (WARN_ON(IS_ERR(crtc_state)))
1089 			return PTR_ERR(crtc_state);
1090 
1091 		crtc_state->plane_mask &= ~(1 << drm_plane_index(plane));
1092 	}
1093 
1094 	plane_state->crtc = crtc;
1095 
1096 	if (crtc) {
1097 		crtc_state = drm_atomic_get_crtc_state(plane_state->state,
1098 						       crtc);
1099 		if (IS_ERR(crtc_state))
1100 			return PTR_ERR(crtc_state);
1101 		crtc_state->plane_mask |= (1 << drm_plane_index(plane));
1102 	}
1103 
1104 	if (crtc)
1105 		DRM_DEBUG_ATOMIC("Link plane state %p to [CRTC:%d:%s]\n",
1106 				 plane_state, crtc->base.id, crtc->name);
1107 	else
1108 		DRM_DEBUG_ATOMIC("Link plane state %p to [NOCRTC]\n",
1109 				 plane_state);
1110 
1111 	return 0;
1112 }
1113 EXPORT_SYMBOL(drm_atomic_set_crtc_for_plane);
1114 
1115 /**
1116  * drm_atomic_set_fb_for_plane - set framebuffer for plane
1117  * @plane_state: atomic state object for the plane
1118  * @fb: fb to use for the plane
1119  *
1120  * Changing the assigned framebuffer for a plane requires us to grab a reference
1121  * to the new fb and drop the reference to the old fb, if there is one. This
1122  * function takes care of all these details besides updating the pointer in the
1123  * state object itself.
1124  */
1125 void
1126 drm_atomic_set_fb_for_plane(struct drm_plane_state *plane_state,
1127 			    struct drm_framebuffer *fb)
1128 {
1129 	if (plane_state->fb)
1130 		drm_framebuffer_unreference(plane_state->fb);
1131 	if (fb)
1132 		drm_framebuffer_reference(fb);
1133 	plane_state->fb = fb;
1134 
1135 	if (fb)
1136 		DRM_DEBUG_ATOMIC("Set [FB:%d] for plane state %p\n",
1137 				 fb->base.id, plane_state);
1138 	else
1139 		DRM_DEBUG_ATOMIC("Set [NOFB] for plane state %p\n",
1140 				 plane_state);
1141 }
1142 EXPORT_SYMBOL(drm_atomic_set_fb_for_plane);
1143 
1144 /**
1145  * drm_atomic_set_crtc_for_connector - set crtc for connector
1146  * @conn_state: atomic state object for the connector
1147  * @crtc: crtc to use for the connector
1148  *
1149  * Changing the assigned crtc for a connector requires us to grab the lock and
1150  * state for the new crtc, as needed. This function takes care of all these
1151  * details besides updating the pointer in the state object itself.
1152  *
1153  * Returns:
1154  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1155  * then the w/w mutex code has detected a deadlock and the entire atomic
1156  * sequence must be restarted. All other errors are fatal.
1157  */
1158 int
1159 drm_atomic_set_crtc_for_connector(struct drm_connector_state *conn_state,
1160 				  struct drm_crtc *crtc)
1161 {
1162 	struct drm_crtc_state *crtc_state;
1163 
1164 	if (conn_state->crtc == crtc)
1165 		return 0;
1166 
1167 	if (conn_state->crtc) {
1168 		crtc_state = drm_atomic_get_existing_crtc_state(conn_state->state,
1169 								conn_state->crtc);
1170 
1171 		crtc_state->connector_mask &=
1172 			~(1 << drm_connector_index(conn_state->connector));
1173 
1174 		drm_connector_unreference(conn_state->connector);
1175 		conn_state->crtc = NULL;
1176 	}
1177 
1178 	if (crtc) {
1179 		crtc_state = drm_atomic_get_crtc_state(conn_state->state, crtc);
1180 		if (IS_ERR(crtc_state))
1181 			return PTR_ERR(crtc_state);
1182 
1183 		crtc_state->connector_mask |=
1184 			1 << drm_connector_index(conn_state->connector);
1185 
1186 		drm_connector_reference(conn_state->connector);
1187 		conn_state->crtc = crtc;
1188 
1189 		DRM_DEBUG_ATOMIC("Link connector state %p to [CRTC:%d:%s]\n",
1190 				 conn_state, crtc->base.id, crtc->name);
1191 	} else {
1192 		DRM_DEBUG_ATOMIC("Link connector state %p to [NOCRTC]\n",
1193 				 conn_state);
1194 	}
1195 
1196 	return 0;
1197 }
1198 EXPORT_SYMBOL(drm_atomic_set_crtc_for_connector);
1199 
1200 /**
1201  * drm_atomic_add_affected_connectors - add connectors for crtc
1202  * @state: atomic state
1203  * @crtc: DRM crtc
1204  *
1205  * This function walks the current configuration and adds all connectors
1206  * currently using @crtc to the atomic configuration @state. Note that this
1207  * function must acquire the connection mutex. This can potentially cause
1208  * unneeded seralization if the update is just for the planes on one crtc. Hence
1209  * drivers and helpers should only call this when really needed (e.g. when a
1210  * full modeset needs to happen due to some change).
1211  *
1212  * Returns:
1213  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1214  * then the w/w mutex code has detected a deadlock and the entire atomic
1215  * sequence must be restarted. All other errors are fatal.
1216  */
1217 int
1218 drm_atomic_add_affected_connectors(struct drm_atomic_state *state,
1219 				   struct drm_crtc *crtc)
1220 {
1221 	struct drm_mode_config *config = &state->dev->mode_config;
1222 	struct drm_connector *connector;
1223 	struct drm_connector_state *conn_state;
1224 	int ret;
1225 
1226 	ret = drm_modeset_lock(&config->connection_mutex, state->acquire_ctx);
1227 	if (ret)
1228 		return ret;
1229 
1230 	DRM_DEBUG_ATOMIC("Adding all current connectors for [CRTC:%d:%s] to %p\n",
1231 			 crtc->base.id, crtc->name, state);
1232 
1233 	/*
1234 	 * Changed connectors are already in @state, so only need to look at the
1235 	 * current configuration.
1236 	 */
1237 	drm_for_each_connector(connector, state->dev) {
1238 		if (connector->state->crtc != crtc)
1239 			continue;
1240 
1241 		conn_state = drm_atomic_get_connector_state(state, connector);
1242 		if (IS_ERR(conn_state))
1243 			return PTR_ERR(conn_state);
1244 	}
1245 
1246 	return 0;
1247 }
1248 EXPORT_SYMBOL(drm_atomic_add_affected_connectors);
1249 
1250 /**
1251  * drm_atomic_add_affected_planes - add planes for crtc
1252  * @state: atomic state
1253  * @crtc: DRM crtc
1254  *
1255  * This function walks the current configuration and adds all planes
1256  * currently used by @crtc to the atomic configuration @state. This is useful
1257  * when an atomic commit also needs to check all currently enabled plane on
1258  * @crtc, e.g. when changing the mode. It's also useful when re-enabling a CRTC
1259  * to avoid special code to force-enable all planes.
1260  *
1261  * Since acquiring a plane state will always also acquire the w/w mutex of the
1262  * current CRTC for that plane (if there is any) adding all the plane states for
1263  * a CRTC will not reduce parallism of atomic updates.
1264  *
1265  * Returns:
1266  * 0 on success or can fail with -EDEADLK or -ENOMEM. When the error is EDEADLK
1267  * then the w/w mutex code has detected a deadlock and the entire atomic
1268  * sequence must be restarted. All other errors are fatal.
1269  */
1270 int
1271 drm_atomic_add_affected_planes(struct drm_atomic_state *state,
1272 			       struct drm_crtc *crtc)
1273 {
1274 	struct drm_plane *plane;
1275 
1276 	WARN_ON(!drm_atomic_get_existing_crtc_state(state, crtc));
1277 
1278 	drm_for_each_plane_mask(plane, state->dev, crtc->state->plane_mask) {
1279 		struct drm_plane_state *plane_state =
1280 			drm_atomic_get_plane_state(state, plane);
1281 
1282 		if (IS_ERR(plane_state))
1283 			return PTR_ERR(plane_state);
1284 	}
1285 	return 0;
1286 }
1287 EXPORT_SYMBOL(drm_atomic_add_affected_planes);
1288 
1289 /**
1290  * drm_atomic_legacy_backoff - locking backoff for legacy ioctls
1291  * @state: atomic state
1292  *
1293  * This function should be used by legacy entry points which don't understand
1294  * -EDEADLK semantics. For simplicity this one will grab all modeset locks after
1295  * the slowpath completed.
1296  */
1297 void drm_atomic_legacy_backoff(struct drm_atomic_state *state)
1298 {
1299 	struct drm_device *dev = state->dev;
1300 	unsigned crtc_mask = 0;
1301 	struct drm_crtc *crtc;
1302 	int ret;
1303 	bool global = false;
1304 
1305 	drm_for_each_crtc(crtc, dev) {
1306 		if (crtc->acquire_ctx != state->acquire_ctx)
1307 			continue;
1308 
1309 		crtc_mask |= drm_crtc_mask(crtc);
1310 		crtc->acquire_ctx = NULL;
1311 	}
1312 
1313 	if (WARN_ON(dev->mode_config.acquire_ctx == state->acquire_ctx)) {
1314 		global = true;
1315 
1316 		dev->mode_config.acquire_ctx = NULL;
1317 	}
1318 
1319 retry:
1320 	drm_modeset_backoff(state->acquire_ctx);
1321 
1322 	ret = drm_modeset_lock_all_ctx(dev, state->acquire_ctx);
1323 	if (ret)
1324 		goto retry;
1325 
1326 	drm_for_each_crtc(crtc, dev)
1327 		if (drm_crtc_mask(crtc) & crtc_mask)
1328 			crtc->acquire_ctx = state->acquire_ctx;
1329 
1330 	if (global)
1331 		dev->mode_config.acquire_ctx = state->acquire_ctx;
1332 }
1333 EXPORT_SYMBOL(drm_atomic_legacy_backoff);
1334 
1335 /**
1336  * drm_atomic_check_only - check whether a given config would work
1337  * @state: atomic configuration to check
1338  *
1339  * Note that this function can return -EDEADLK if the driver needed to acquire
1340  * more locks but encountered a deadlock. The caller must then do the usual w/w
1341  * backoff dance and restart. All other errors are fatal.
1342  *
1343  * Returns:
1344  * 0 on success, negative error code on failure.
1345  */
1346 int drm_atomic_check_only(struct drm_atomic_state *state)
1347 {
1348 	struct drm_device *dev = state->dev;
1349 	struct drm_mode_config *config = &dev->mode_config;
1350 	struct drm_plane *plane;
1351 	struct drm_plane_state *plane_state;
1352 	struct drm_crtc *crtc;
1353 	struct drm_crtc_state *crtc_state;
1354 	int i, ret = 0;
1355 
1356 	DRM_DEBUG_ATOMIC("checking %p\n", state);
1357 
1358 	for_each_plane_in_state(state, plane, plane_state, i) {
1359 		ret = drm_atomic_plane_check(plane, plane_state);
1360 		if (ret) {
1361 			DRM_DEBUG_ATOMIC("[PLANE:%d:%s] atomic core check failed\n",
1362 					 plane->base.id, plane->name);
1363 			return ret;
1364 		}
1365 	}
1366 
1367 	for_each_crtc_in_state(state, crtc, crtc_state, i) {
1368 		ret = drm_atomic_crtc_check(crtc, crtc_state);
1369 		if (ret) {
1370 			DRM_DEBUG_ATOMIC("[CRTC:%d:%s] atomic core check failed\n",
1371 					 crtc->base.id, crtc->name);
1372 			return ret;
1373 		}
1374 	}
1375 
1376 	if (config->funcs->atomic_check)
1377 		ret = config->funcs->atomic_check(state->dev, state);
1378 
1379 	if (!state->allow_modeset) {
1380 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1381 			if (drm_atomic_crtc_needs_modeset(crtc_state)) {
1382 				DRM_DEBUG_ATOMIC("[CRTC:%d:%s] requires full modeset\n",
1383 						 crtc->base.id, crtc->name);
1384 				return -EINVAL;
1385 			}
1386 		}
1387 	}
1388 
1389 	return ret;
1390 }
1391 EXPORT_SYMBOL(drm_atomic_check_only);
1392 
1393 /**
1394  * drm_atomic_commit - commit configuration atomically
1395  * @state: atomic configuration to check
1396  *
1397  * Note that this function can return -EDEADLK if the driver needed to acquire
1398  * more locks but encountered a deadlock. The caller must then do the usual w/w
1399  * backoff dance and restart. All other errors are fatal.
1400  *
1401  * Also note that on successful execution ownership of @state is transferred
1402  * from the caller of this function to the function itself. The caller must not
1403  * free or in any other way access @state. If the function fails then the caller
1404  * must clean up @state itself.
1405  *
1406  * Returns:
1407  * 0 on success, negative error code on failure.
1408  */
1409 int drm_atomic_commit(struct drm_atomic_state *state)
1410 {
1411 	struct drm_mode_config *config = &state->dev->mode_config;
1412 	int ret;
1413 
1414 	ret = drm_atomic_check_only(state);
1415 	if (ret)
1416 		return ret;
1417 
1418 	DRM_DEBUG_ATOMIC("commiting %p\n", state);
1419 
1420 	return config->funcs->atomic_commit(state->dev, state, false);
1421 }
1422 EXPORT_SYMBOL(drm_atomic_commit);
1423 
1424 /**
1425  * drm_atomic_nonblocking_commit - atomic&nonblocking configuration commit
1426  * @state: atomic configuration to check
1427  *
1428  * Note that this function can return -EDEADLK if the driver needed to acquire
1429  * more locks but encountered a deadlock. The caller must then do the usual w/w
1430  * backoff dance and restart. All other errors are fatal.
1431  *
1432  * Also note that on successful execution ownership of @state is transferred
1433  * from the caller of this function to the function itself. The caller must not
1434  * free or in any other way access @state. If the function fails then the caller
1435  * must clean up @state itself.
1436  *
1437  * Returns:
1438  * 0 on success, negative error code on failure.
1439  */
1440 int drm_atomic_nonblocking_commit(struct drm_atomic_state *state)
1441 {
1442 	struct drm_mode_config *config = &state->dev->mode_config;
1443 	int ret;
1444 
1445 	ret = drm_atomic_check_only(state);
1446 	if (ret)
1447 		return ret;
1448 
1449 	DRM_DEBUG_ATOMIC("commiting %p nonblocking\n", state);
1450 
1451 	return config->funcs->atomic_commit(state->dev, state, true);
1452 }
1453 EXPORT_SYMBOL(drm_atomic_nonblocking_commit);
1454 
1455 /*
1456  * The big monstor ioctl
1457  */
1458 
1459 static struct drm_pending_vblank_event *create_vblank_event(
1460 		struct drm_device *dev, struct drm_file *file_priv, uint64_t user_data)
1461 {
1462 	struct drm_pending_vblank_event *e = NULL;
1463 	int ret;
1464 
1465 	e = kzalloc(sizeof *e, GFP_KERNEL);
1466 	if (!e)
1467 		return NULL;
1468 
1469 	e->event.base.type = DRM_EVENT_FLIP_COMPLETE;
1470 	e->event.base.length = sizeof(e->event);
1471 	e->event.user_data = user_data;
1472 
1473 	ret = drm_event_reserve_init(dev, file_priv, &e->base, &e->event.base);
1474 	if (ret) {
1475 		kfree(e);
1476 		return NULL;
1477 	}
1478 
1479 	return e;
1480 }
1481 
1482 static int atomic_set_prop(struct drm_atomic_state *state,
1483 		struct drm_mode_object *obj, struct drm_property *prop,
1484 		uint64_t prop_value)
1485 {
1486 	struct drm_mode_object *ref;
1487 	int ret;
1488 
1489 	if (!drm_property_change_valid_get(prop, prop_value, &ref))
1490 		return -EINVAL;
1491 
1492 	switch (obj->type) {
1493 	case DRM_MODE_OBJECT_CONNECTOR: {
1494 		struct drm_connector *connector = obj_to_connector(obj);
1495 		struct drm_connector_state *connector_state;
1496 
1497 		connector_state = drm_atomic_get_connector_state(state, connector);
1498 		if (IS_ERR(connector_state)) {
1499 			ret = PTR_ERR(connector_state);
1500 			break;
1501 		}
1502 
1503 		ret = drm_atomic_connector_set_property(connector,
1504 				connector_state, prop, prop_value);
1505 		break;
1506 	}
1507 	case DRM_MODE_OBJECT_CRTC: {
1508 		struct drm_crtc *crtc = obj_to_crtc(obj);
1509 		struct drm_crtc_state *crtc_state;
1510 
1511 		crtc_state = drm_atomic_get_crtc_state(state, crtc);
1512 		if (IS_ERR(crtc_state)) {
1513 			ret = PTR_ERR(crtc_state);
1514 			break;
1515 		}
1516 
1517 		ret = drm_atomic_crtc_set_property(crtc,
1518 				crtc_state, prop, prop_value);
1519 		break;
1520 	}
1521 	case DRM_MODE_OBJECT_PLANE: {
1522 		struct drm_plane *plane = obj_to_plane(obj);
1523 		struct drm_plane_state *plane_state;
1524 
1525 		plane_state = drm_atomic_get_plane_state(state, plane);
1526 		if (IS_ERR(plane_state)) {
1527 			ret = PTR_ERR(plane_state);
1528 			break;
1529 		}
1530 
1531 		ret = drm_atomic_plane_set_property(plane,
1532 				plane_state, prop, prop_value);
1533 		break;
1534 	}
1535 	default:
1536 		ret = -EINVAL;
1537 		break;
1538 	}
1539 
1540 	drm_property_change_valid_put(prop, ref);
1541 	return ret;
1542 }
1543 
1544 /**
1545  * drm_atomic_clean_old_fb -- Unset old_fb pointers and set plane->fb pointers.
1546  *
1547  * @dev: drm device to check.
1548  * @plane_mask: plane mask for planes that were updated.
1549  * @ret: return value, can be -EDEADLK for a retry.
1550  *
1551  * Before doing an update plane->old_fb is set to plane->fb,
1552  * but before dropping the locks old_fb needs to be set to NULL
1553  * and plane->fb updated. This is a common operation for each
1554  * atomic update, so this call is split off as a helper.
1555  */
1556 void drm_atomic_clean_old_fb(struct drm_device *dev,
1557 			     unsigned plane_mask,
1558 			     int ret)
1559 {
1560 	struct drm_plane *plane;
1561 
1562 	/* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
1563 	 * locks (ie. while it is still safe to deref plane->state).  We
1564 	 * need to do this here because the driver entry points cannot
1565 	 * distinguish between legacy and atomic ioctls.
1566 	 */
1567 	drm_for_each_plane_mask(plane, dev, plane_mask) {
1568 		if (ret == 0) {
1569 			struct drm_framebuffer *new_fb = plane->state->fb;
1570 			if (new_fb)
1571 				drm_framebuffer_reference(new_fb);
1572 			plane->fb = new_fb;
1573 			plane->crtc = plane->state->crtc;
1574 
1575 			if (plane->old_fb)
1576 				drm_framebuffer_unreference(plane->old_fb);
1577 		}
1578 		plane->old_fb = NULL;
1579 	}
1580 }
1581 EXPORT_SYMBOL(drm_atomic_clean_old_fb);
1582 
1583 int drm_mode_atomic_ioctl(struct drm_device *dev,
1584 			  void *data, struct drm_file *file_priv)
1585 {
1586 	struct drm_mode_atomic *arg = data;
1587 	uint32_t __user *objs_ptr = (uint32_t __user *)(unsigned long)(arg->objs_ptr);
1588 	uint32_t __user *count_props_ptr = (uint32_t __user *)(unsigned long)(arg->count_props_ptr);
1589 	uint32_t __user *props_ptr = (uint32_t __user *)(unsigned long)(arg->props_ptr);
1590 	uint64_t __user *prop_values_ptr = (uint64_t __user *)(unsigned long)(arg->prop_values_ptr);
1591 	unsigned int copied_objs, copied_props;
1592 	struct drm_atomic_state *state;
1593 	struct drm_modeset_acquire_ctx ctx;
1594 	struct drm_plane *plane;
1595 	struct drm_crtc *crtc;
1596 	struct drm_crtc_state *crtc_state;
1597 	unsigned plane_mask;
1598 	int ret = 0;
1599 	unsigned int i, j;
1600 
1601 	/* disallow for drivers not supporting atomic: */
1602 	if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
1603 		return -EINVAL;
1604 
1605 	/* disallow for userspace that has not enabled atomic cap (even
1606 	 * though this may be a bit overkill, since legacy userspace
1607 	 * wouldn't know how to call this ioctl)
1608 	 */
1609 	if (!file_priv->atomic)
1610 		return -EINVAL;
1611 
1612 	if (arg->flags & ~DRM_MODE_ATOMIC_FLAGS)
1613 		return -EINVAL;
1614 
1615 	if (arg->reserved)
1616 		return -EINVAL;
1617 
1618 	if ((arg->flags & DRM_MODE_PAGE_FLIP_ASYNC) &&
1619 			!dev->mode_config.async_page_flip)
1620 		return -EINVAL;
1621 
1622 	/* can't test and expect an event at the same time. */
1623 	if ((arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) &&
1624 			(arg->flags & DRM_MODE_PAGE_FLIP_EVENT))
1625 		return -EINVAL;
1626 
1627 	drm_modeset_acquire_init(&ctx, 0);
1628 
1629 	state = drm_atomic_state_alloc(dev);
1630 	if (!state)
1631 		return -ENOMEM;
1632 
1633 	state->acquire_ctx = &ctx;
1634 	state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
1635 
1636 retry:
1637 	plane_mask = 0;
1638 	copied_objs = 0;
1639 	copied_props = 0;
1640 
1641 	for (i = 0; i < arg->count_objs; i++) {
1642 		uint32_t obj_id, count_props;
1643 		struct drm_mode_object *obj;
1644 
1645 		if (get_user(obj_id, objs_ptr + copied_objs)) {
1646 			ret = -EFAULT;
1647 			goto out;
1648 		}
1649 
1650 		obj = drm_mode_object_find(dev, obj_id, DRM_MODE_OBJECT_ANY);
1651 		if (!obj) {
1652 			ret = -ENOENT;
1653 			goto out;
1654 		}
1655 
1656 		if (!obj->properties) {
1657 			drm_mode_object_unreference(obj);
1658 			ret = -ENOENT;
1659 			goto out;
1660 		}
1661 
1662 		if (get_user(count_props, count_props_ptr + copied_objs)) {
1663 			drm_mode_object_unreference(obj);
1664 			ret = -EFAULT;
1665 			goto out;
1666 		}
1667 
1668 		copied_objs++;
1669 
1670 		for (j = 0; j < count_props; j++) {
1671 			uint32_t prop_id;
1672 			uint64_t prop_value;
1673 			struct drm_property *prop;
1674 
1675 			if (get_user(prop_id, props_ptr + copied_props)) {
1676 				drm_mode_object_unreference(obj);
1677 				ret = -EFAULT;
1678 				goto out;
1679 			}
1680 
1681 			prop = drm_property_find(dev, prop_id);
1682 			if (!prop) {
1683 				drm_mode_object_unreference(obj);
1684 				ret = -ENOENT;
1685 				goto out;
1686 			}
1687 
1688 			if (copy_from_user(&prop_value,
1689 					   prop_values_ptr + copied_props,
1690 					   sizeof(prop_value))) {
1691 				drm_mode_object_unreference(obj);
1692 				ret = -EFAULT;
1693 				goto out;
1694 			}
1695 
1696 			ret = atomic_set_prop(state, obj, prop, prop_value);
1697 			if (ret) {
1698 				drm_mode_object_unreference(obj);
1699 				goto out;
1700 			}
1701 
1702 			copied_props++;
1703 		}
1704 
1705 		if (obj->type == DRM_MODE_OBJECT_PLANE && count_props &&
1706 		    !(arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)) {
1707 			plane = obj_to_plane(obj);
1708 			plane_mask |= (1 << drm_plane_index(plane));
1709 			plane->old_fb = plane->fb;
1710 		}
1711 		drm_mode_object_unreference(obj);
1712 	}
1713 
1714 	if (arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1715 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1716 			struct drm_pending_vblank_event *e;
1717 
1718 			e = create_vblank_event(dev, file_priv, arg->user_data);
1719 			if (!e) {
1720 				ret = -ENOMEM;
1721 				goto out;
1722 			}
1723 
1724 			crtc_state->event = e;
1725 		}
1726 	}
1727 
1728 	if (arg->flags & DRM_MODE_ATOMIC_TEST_ONLY) {
1729 		/*
1730 		 * Unlike commit, check_only does not clean up state.
1731 		 * Below we call drm_atomic_state_free for it.
1732 		 */
1733 		ret = drm_atomic_check_only(state);
1734 	} else if (arg->flags & DRM_MODE_ATOMIC_NONBLOCK) {
1735 		ret = drm_atomic_nonblocking_commit(state);
1736 	} else {
1737 		ret = drm_atomic_commit(state);
1738 	}
1739 
1740 out:
1741 	drm_atomic_clean_old_fb(dev, plane_mask, ret);
1742 
1743 	if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
1744 		/*
1745 		 * TEST_ONLY and PAGE_FLIP_EVENT are mutually exclusive,
1746 		 * if they weren't, this code should be called on success
1747 		 * for TEST_ONLY too.
1748 		 */
1749 
1750 		for_each_crtc_in_state(state, crtc, crtc_state, i) {
1751 			if (!crtc_state->event)
1752 				continue;
1753 
1754 			drm_event_cancel_free(dev, &crtc_state->event->base);
1755 		}
1756 	}
1757 
1758 	if (ret == -EDEADLK) {
1759 		drm_atomic_state_clear(state);
1760 		drm_modeset_backoff(&ctx);
1761 		goto retry;
1762 	}
1763 
1764 	if (ret || arg->flags & DRM_MODE_ATOMIC_TEST_ONLY)
1765 		drm_atomic_state_free(state);
1766 
1767 	drm_modeset_drop_locks(&ctx);
1768 	drm_modeset_acquire_fini(&ctx);
1769 
1770 	return ret;
1771 }
1772