1 /*
2  * Copyright (c) 2016 Intel Corporation
3  *
4  * Permission to use, copy, modify, distribute, and sell this software and its
5  * documentation for any purpose is hereby granted without fee, provided that
6  * the above copyright notice appear in all copies and that both that copyright
7  * notice and this permission notice appear in supporting documentation, and
8  * that the name of the copyright holders not be used in advertising or
9  * publicity pertaining to distribution of the software without specific,
10  * written prior permission.  The copyright holders make no representations
11  * about the suitability of this software for any purpose.  It is provided "as
12  * is" without express or implied warranty.
13  *
14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20  * OF THIS SOFTWARE.
21  */
22 
23 #include <linux/export.h>
24 #include <drm/drmP.h>
25 #include <drm/drm_auth.h>
26 #include <drm/drm_framebuffer.h>
27 #include <drm/drm_atomic.h>
28 #include <drm/drm_print.h>
29 
30 #include "drm_internal.h"
31 #include "drm_crtc_internal.h"
32 
33 /**
34  * DOC: overview
35  *
36  * Frame buffers are abstract memory objects that provide a source of pixels to
37  * scanout to a CRTC. Applications explicitly request the creation of frame
38  * buffers through the DRM_IOCTL_MODE_ADDFB(2) ioctls and receive an opaque
39  * handle that can be passed to the KMS CRTC control, plane configuration and
40  * page flip functions.
41  *
42  * Frame buffers rely on the underlying memory manager for allocating backing
43  * storage. When creating a frame buffer applications pass a memory handle
44  * (or a list of memory handles for multi-planar formats) through the
45  * &struct drm_mode_fb_cmd2 argument. For drivers using GEM as their userspace
46  * buffer management interface this would be a GEM handle.  Drivers are however
47  * free to use their own backing storage object handles, e.g. vmwgfx directly
48  * exposes special TTM handles to userspace and so expects TTM handles in the
49  * create ioctl and not GEM handles.
50  *
51  * Framebuffers are tracked with &struct drm_framebuffer. They are published
52  * using drm_framebuffer_init() - after calling that function userspace can use
53  * and access the framebuffer object. The helper function
54  * drm_helper_mode_fill_fb_struct() can be used to pre-fill the required
55  * metadata fields.
56  *
57  * The lifetime of a drm framebuffer is controlled with a reference count,
58  * drivers can grab additional references with drm_framebuffer_get() and drop
59  * them again with drm_framebuffer_put(). For driver-private framebuffers for
60  * which the last reference is never dropped (e.g. for the fbdev framebuffer
61  * when the struct &struct drm_framebuffer is embedded into the fbdev helper
62  * struct) drivers can manually clean up a framebuffer at module unload time
63  * with drm_framebuffer_unregister_private(). But doing this is not
64  * recommended, and it's better to have a normal free-standing &struct
65  * drm_framebuffer.
66  */
67 
68 int drm_framebuffer_check_src_coords(uint32_t src_x, uint32_t src_y,
69 				     uint32_t src_w, uint32_t src_h,
70 				     const struct drm_framebuffer *fb)
71 {
72 	unsigned int fb_width, fb_height;
73 
74 	fb_width = fb->width << 16;
75 	fb_height = fb->height << 16;
76 
77 	/* Make sure source coordinates are inside the fb. */
78 	if (src_w > fb_width ||
79 	    src_x > fb_width - src_w ||
80 	    src_h > fb_height ||
81 	    src_y > fb_height - src_h) {
82 		DRM_DEBUG_KMS("Invalid source coordinates "
83 			      "%u.%06ux%u.%06u+%u.%06u+%u.%06u (fb %ux%u)\n",
84 			      src_w >> 16, ((src_w & 0xffff) * 15625) >> 10,
85 			      src_h >> 16, ((src_h & 0xffff) * 15625) >> 10,
86 			      src_x >> 16, ((src_x & 0xffff) * 15625) >> 10,
87 			      src_y >> 16, ((src_y & 0xffff) * 15625) >> 10,
88 			      fb->width, fb->height);
89 		return -ENOSPC;
90 	}
91 
92 	return 0;
93 }
94 
95 /**
96  * drm_mode_addfb - add an FB to the graphics configuration
97  * @dev: drm device for the ioctl
98  * @data: data pointer for the ioctl
99  * @file_priv: drm file for the ioctl call
100  *
101  * Add a new FB to the specified CRTC, given a user request. This is the
102  * original addfb ioctl which only supported RGB formats.
103  *
104  * Called by the user via ioctl.
105  *
106  * Returns:
107  * Zero on success, negative errno on failure.
108  */
109 int drm_mode_addfb(struct drm_device *dev,
110 		   void *data, struct drm_file *file_priv)
111 {
112 	struct drm_mode_fb_cmd *or = data;
113 	struct drm_mode_fb_cmd2 r = {};
114 	int ret;
115 
116 	/* convert to new format and call new ioctl */
117 	r.fb_id = or->fb_id;
118 	r.width = or->width;
119 	r.height = or->height;
120 	r.pitches[0] = or->pitch;
121 	r.pixel_format = drm_mode_legacy_fb_format(or->bpp, or->depth);
122 	r.handles[0] = or->handle;
123 
124 	if (r.pixel_format == DRM_FORMAT_XRGB2101010 &&
125 	    dev->driver->driver_features & DRIVER_PREFER_XBGR_30BPP)
126 		r.pixel_format = DRM_FORMAT_XBGR2101010;
127 
128 	ret = drm_mode_addfb2(dev, &r, file_priv);
129 	if (ret)
130 		return ret;
131 
132 	or->fb_id = r.fb_id;
133 
134 	return 0;
135 }
136 
137 static int fb_plane_width(int width,
138 			  const struct drm_format_info *format, int plane)
139 {
140 	if (plane == 0)
141 		return width;
142 
143 	return DIV_ROUND_UP(width, format->hsub);
144 }
145 
146 static int fb_plane_height(int height,
147 			   const struct drm_format_info *format, int plane)
148 {
149 	if (plane == 0)
150 		return height;
151 
152 	return DIV_ROUND_UP(height, format->vsub);
153 }
154 
155 static int framebuffer_check(struct drm_device *dev,
156 			     const struct drm_mode_fb_cmd2 *r)
157 {
158 	const struct drm_format_info *info;
159 	int i;
160 
161 	/* check if the format is supported at all */
162 	info = __drm_format_info(r->pixel_format & ~DRM_FORMAT_BIG_ENDIAN);
163 	if (!info) {
164 		struct drm_format_name_buf format_name;
165 
166 		DRM_DEBUG_KMS("bad framebuffer format %s\n",
167 			      drm_get_format_name(r->pixel_format,
168 						  &format_name));
169 		return -EINVAL;
170 	}
171 
172 	/* now let the driver pick its own format info */
173 	info = drm_get_format_info(dev, r);
174 
175 	if (r->width == 0) {
176 		DRM_DEBUG_KMS("bad framebuffer width %u\n", r->width);
177 		return -EINVAL;
178 	}
179 
180 	if (r->height == 0) {
181 		DRM_DEBUG_KMS("bad framebuffer height %u\n", r->height);
182 		return -EINVAL;
183 	}
184 
185 	for (i = 0; i < info->num_planes; i++) {
186 		unsigned int width = fb_plane_width(r->width, info, i);
187 		unsigned int height = fb_plane_height(r->height, info, i);
188 		unsigned int cpp = info->cpp[i];
189 
190 		if (!r->handles[i]) {
191 			DRM_DEBUG_KMS("no buffer object handle for plane %d\n", i);
192 			return -EINVAL;
193 		}
194 
195 		if ((uint64_t) width * cpp > UINT_MAX)
196 			return -ERANGE;
197 
198 		if ((uint64_t) height * r->pitches[i] + r->offsets[i] > UINT_MAX)
199 			return -ERANGE;
200 
201 		if (r->pitches[i] < width * cpp) {
202 			DRM_DEBUG_KMS("bad pitch %u for plane %d\n", r->pitches[i], i);
203 			return -EINVAL;
204 		}
205 
206 		if (r->modifier[i] && !(r->flags & DRM_MODE_FB_MODIFIERS)) {
207 			DRM_DEBUG_KMS("bad fb modifier %llu for plane %d\n",
208 				      r->modifier[i], i);
209 			return -EINVAL;
210 		}
211 
212 		if (r->flags & DRM_MODE_FB_MODIFIERS &&
213 		    r->modifier[i] != r->modifier[0]) {
214 			DRM_DEBUG_KMS("bad fb modifier %llu for plane %d\n",
215 				      r->modifier[i], i);
216 			return -EINVAL;
217 		}
218 
219 		/* modifier specific checks: */
220 		switch (r->modifier[i]) {
221 		case DRM_FORMAT_MOD_SAMSUNG_64_32_TILE:
222 			/* NOTE: the pitch restriction may be lifted later if it turns
223 			 * out that no hw has this restriction:
224 			 */
225 			if (r->pixel_format != DRM_FORMAT_NV12 ||
226 					width % 128 || height % 32 ||
227 					r->pitches[i] % 128) {
228 				DRM_DEBUG_KMS("bad modifier data for plane %d\n", i);
229 				return -EINVAL;
230 			}
231 			break;
232 
233 		default:
234 			break;
235 		}
236 	}
237 
238 	for (i = info->num_planes; i < 4; i++) {
239 		if (r->modifier[i]) {
240 			DRM_DEBUG_KMS("non-zero modifier for unused plane %d\n", i);
241 			return -EINVAL;
242 		}
243 
244 		/* Pre-FB_MODIFIERS userspace didn't clear the structs properly. */
245 		if (!(r->flags & DRM_MODE_FB_MODIFIERS))
246 			continue;
247 
248 		if (r->handles[i]) {
249 			DRM_DEBUG_KMS("buffer object handle for unused plane %d\n", i);
250 			return -EINVAL;
251 		}
252 
253 		if (r->pitches[i]) {
254 			DRM_DEBUG_KMS("non-zero pitch for unused plane %d\n", i);
255 			return -EINVAL;
256 		}
257 
258 		if (r->offsets[i]) {
259 			DRM_DEBUG_KMS("non-zero offset for unused plane %d\n", i);
260 			return -EINVAL;
261 		}
262 	}
263 
264 	return 0;
265 }
266 
267 struct drm_framebuffer *
268 drm_internal_framebuffer_create(struct drm_device *dev,
269 				const struct drm_mode_fb_cmd2 *r,
270 				struct drm_file *file_priv)
271 {
272 	struct drm_mode_config *config = &dev->mode_config;
273 	struct drm_framebuffer *fb;
274 	int ret;
275 
276 	if (r->flags & ~(DRM_MODE_FB_INTERLACED | DRM_MODE_FB_MODIFIERS)) {
277 		DRM_DEBUG_KMS("bad framebuffer flags 0x%08x\n", r->flags);
278 		return ERR_PTR(-EINVAL);
279 	}
280 
281 	if ((config->min_width > r->width) || (r->width > config->max_width)) {
282 		DRM_DEBUG_KMS("bad framebuffer width %d, should be >= %d && <= %d\n",
283 			  r->width, config->min_width, config->max_width);
284 		return ERR_PTR(-EINVAL);
285 	}
286 	if ((config->min_height > r->height) || (r->height > config->max_height)) {
287 		DRM_DEBUG_KMS("bad framebuffer height %d, should be >= %d && <= %d\n",
288 			  r->height, config->min_height, config->max_height);
289 		return ERR_PTR(-EINVAL);
290 	}
291 
292 	if (r->flags & DRM_MODE_FB_MODIFIERS &&
293 	    !dev->mode_config.allow_fb_modifiers) {
294 		DRM_DEBUG_KMS("driver does not support fb modifiers\n");
295 		return ERR_PTR(-EINVAL);
296 	}
297 
298 	ret = framebuffer_check(dev, r);
299 	if (ret)
300 		return ERR_PTR(ret);
301 
302 	fb = dev->mode_config.funcs->fb_create(dev, file_priv, r);
303 	if (IS_ERR(fb)) {
304 		DRM_DEBUG_KMS("could not create framebuffer\n");
305 		return fb;
306 	}
307 
308 	return fb;
309 }
310 
311 /**
312  * drm_mode_addfb2 - add an FB to the graphics configuration
313  * @dev: drm device for the ioctl
314  * @data: data pointer for the ioctl
315  * @file_priv: drm file for the ioctl call
316  *
317  * Add a new FB to the specified CRTC, given a user request with format. This is
318  * the 2nd version of the addfb ioctl, which supports multi-planar framebuffers
319  * and uses fourcc codes as pixel format specifiers.
320  *
321  * Called by the user via ioctl.
322  *
323  * Returns:
324  * Zero on success, negative errno on failure.
325  */
326 int drm_mode_addfb2(struct drm_device *dev,
327 		    void *data, struct drm_file *file_priv)
328 {
329 	struct drm_mode_fb_cmd2 *r = data;
330 	struct drm_framebuffer *fb;
331 
332 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
333 		return -EINVAL;
334 
335 	fb = drm_internal_framebuffer_create(dev, r, file_priv);
336 	if (IS_ERR(fb))
337 		return PTR_ERR(fb);
338 
339 	DRM_DEBUG_KMS("[FB:%d]\n", fb->base.id);
340 	r->fb_id = fb->base.id;
341 
342 	/* Transfer ownership to the filp for reaping on close */
343 	mutex_lock(&file_priv->fbs_lock);
344 	list_add(&fb->filp_head, &file_priv->fbs);
345 	mutex_unlock(&file_priv->fbs_lock);
346 
347 	return 0;
348 }
349 
350 struct drm_mode_rmfb_work {
351 	struct work_struct work;
352 	struct list_head fbs;
353 };
354 
355 static void drm_mode_rmfb_work_fn(struct work_struct *w)
356 {
357 	struct drm_mode_rmfb_work *arg = container_of(w, typeof(*arg), work);
358 
359 	while (!list_empty(&arg->fbs)) {
360 		struct drm_framebuffer *fb =
361 			list_first_entry(&arg->fbs, typeof(*fb), filp_head);
362 
363 		list_del_init(&fb->filp_head);
364 		drm_framebuffer_remove(fb);
365 	}
366 }
367 
368 /**
369  * drm_mode_rmfb - remove an FB from the configuration
370  * @dev: drm device for the ioctl
371  * @data: data pointer for the ioctl
372  * @file_priv: drm file for the ioctl call
373  *
374  * Remove the FB specified by the user.
375  *
376  * Called by the user via ioctl.
377  *
378  * Returns:
379  * Zero on success, negative errno on failure.
380  */
381 int drm_mode_rmfb(struct drm_device *dev,
382 		   void *data, struct drm_file *file_priv)
383 {
384 	struct drm_framebuffer *fb = NULL;
385 	struct drm_framebuffer *fbl = NULL;
386 	uint32_t *id = data;
387 	int found = 0;
388 
389 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
390 		return -EINVAL;
391 
392 	fb = drm_framebuffer_lookup(dev, file_priv, *id);
393 	if (!fb)
394 		return -ENOENT;
395 
396 	mutex_lock(&file_priv->fbs_lock);
397 	list_for_each_entry(fbl, &file_priv->fbs, filp_head)
398 		if (fb == fbl)
399 			found = 1;
400 	if (!found) {
401 		mutex_unlock(&file_priv->fbs_lock);
402 		goto fail_unref;
403 	}
404 
405 	list_del_init(&fb->filp_head);
406 	mutex_unlock(&file_priv->fbs_lock);
407 
408 	/* drop the reference we picked up in framebuffer lookup */
409 	drm_framebuffer_put(fb);
410 
411 	/*
412 	 * we now own the reference that was stored in the fbs list
413 	 *
414 	 * drm_framebuffer_remove may fail with -EINTR on pending signals,
415 	 * so run this in a separate stack as there's no way to correctly
416 	 * handle this after the fb is already removed from the lookup table.
417 	 */
418 	if (drm_framebuffer_read_refcount(fb) > 1) {
419 		struct drm_mode_rmfb_work arg;
420 
421 		INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);
422 		INIT_LIST_HEAD(&arg.fbs);
423 		list_add_tail(&fb->filp_head, &arg.fbs);
424 
425 		schedule_work(&arg.work);
426 		flush_work(&arg.work);
427 		destroy_work_on_stack(&arg.work);
428 	} else
429 		drm_framebuffer_put(fb);
430 
431 	return 0;
432 
433 fail_unref:
434 	drm_framebuffer_put(fb);
435 	return -ENOENT;
436 }
437 
438 /**
439  * drm_mode_getfb - get FB info
440  * @dev: drm device for the ioctl
441  * @data: data pointer for the ioctl
442  * @file_priv: drm file for the ioctl call
443  *
444  * Lookup the FB given its ID and return info about it.
445  *
446  * Called by the user via ioctl.
447  *
448  * Returns:
449  * Zero on success, negative errno on failure.
450  */
451 int drm_mode_getfb(struct drm_device *dev,
452 		   void *data, struct drm_file *file_priv)
453 {
454 	struct drm_mode_fb_cmd *r = data;
455 	struct drm_framebuffer *fb;
456 	int ret;
457 
458 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
459 		return -EINVAL;
460 
461 	fb = drm_framebuffer_lookup(dev, file_priv, r->fb_id);
462 	if (!fb)
463 		return -ENOENT;
464 
465 	/* Multi-planar framebuffers need getfb2. */
466 	if (fb->format->num_planes > 1) {
467 		ret = -EINVAL;
468 		goto out;
469 	}
470 
471 	if (!fb->funcs->create_handle) {
472 		ret = -ENODEV;
473 		goto out;
474 	}
475 
476 	r->height = fb->height;
477 	r->width = fb->width;
478 	r->depth = fb->format->depth;
479 	r->bpp = fb->format->cpp[0] * 8;
480 	r->pitch = fb->pitches[0];
481 
482 	/* GET_FB() is an unprivileged ioctl so we must not return a
483 	 * buffer-handle to non-master processes! For
484 	 * backwards-compatibility reasons, we cannot make GET_FB() privileged,
485 	 * so just return an invalid handle for non-masters.
486 	 */
487 	if (!drm_is_current_master(file_priv) && !capable(CAP_SYS_ADMIN)) {
488 		r->handle = 0;
489 		ret = 0;
490 		goto out;
491 	}
492 
493 	ret = fb->funcs->create_handle(fb, file_priv, &r->handle);
494 
495 out:
496 	drm_framebuffer_put(fb);
497 
498 	return ret;
499 }
500 
501 /**
502  * drm_mode_dirtyfb_ioctl - flush frontbuffer rendering on an FB
503  * @dev: drm device for the ioctl
504  * @data: data pointer for the ioctl
505  * @file_priv: drm file for the ioctl call
506  *
507  * Lookup the FB and flush out the damaged area supplied by userspace as a clip
508  * rectangle list. Generic userspace which does frontbuffer rendering must call
509  * this ioctl to flush out the changes on manual-update display outputs, e.g.
510  * usb display-link, mipi manual update panels or edp panel self refresh modes.
511  *
512  * Modesetting drivers which always update the frontbuffer do not need to
513  * implement the corresponding &drm_framebuffer_funcs.dirty callback.
514  *
515  * Called by the user via ioctl.
516  *
517  * Returns:
518  * Zero on success, negative errno on failure.
519  */
520 int drm_mode_dirtyfb_ioctl(struct drm_device *dev,
521 			   void *data, struct drm_file *file_priv)
522 {
523 	struct drm_clip_rect __user *clips_ptr;
524 	struct drm_clip_rect *clips = NULL;
525 	struct drm_mode_fb_dirty_cmd *r = data;
526 	struct drm_framebuffer *fb;
527 	unsigned flags;
528 	int num_clips;
529 	int ret;
530 
531 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
532 		return -EINVAL;
533 
534 	fb = drm_framebuffer_lookup(dev, file_priv, r->fb_id);
535 	if (!fb)
536 		return -ENOENT;
537 
538 	num_clips = r->num_clips;
539 	clips_ptr = (struct drm_clip_rect __user *)(unsigned long)r->clips_ptr;
540 
541 	if (!num_clips != !clips_ptr) {
542 		ret = -EINVAL;
543 		goto out_err1;
544 	}
545 
546 	flags = DRM_MODE_FB_DIRTY_FLAGS & r->flags;
547 
548 	/* If userspace annotates copy, clips must come in pairs */
549 	if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY && (num_clips % 2)) {
550 		ret = -EINVAL;
551 		goto out_err1;
552 	}
553 
554 	if (num_clips && clips_ptr) {
555 		if (num_clips < 0 || num_clips > DRM_MODE_FB_DIRTY_MAX_CLIPS) {
556 			ret = -EINVAL;
557 			goto out_err1;
558 		}
559 		clips = kcalloc(num_clips, sizeof(*clips), GFP_KERNEL);
560 		if (!clips) {
561 			ret = -ENOMEM;
562 			goto out_err1;
563 		}
564 
565 		ret = copy_from_user(clips, clips_ptr,
566 				     num_clips * sizeof(*clips));
567 		if (ret) {
568 			ret = -EFAULT;
569 			goto out_err2;
570 		}
571 	}
572 
573 	if (fb->funcs->dirty) {
574 		ret = fb->funcs->dirty(fb, file_priv, flags, r->color,
575 				       clips, num_clips);
576 	} else {
577 		ret = -ENOSYS;
578 	}
579 
580 out_err2:
581 	kfree(clips);
582 out_err1:
583 	drm_framebuffer_put(fb);
584 
585 	return ret;
586 }
587 
588 /**
589  * drm_fb_release - remove and free the FBs on this file
590  * @priv: drm file for the ioctl
591  *
592  * Destroy all the FBs associated with @filp.
593  *
594  * Called by the user via ioctl.
595  *
596  * Returns:
597  * Zero on success, negative errno on failure.
598  */
599 void drm_fb_release(struct drm_file *priv)
600 {
601 	struct drm_framebuffer *fb, *tfb;
602 	struct drm_mode_rmfb_work arg;
603 
604 	INIT_LIST_HEAD(&arg.fbs);
605 
606 	/*
607 	 * When the file gets released that means no one else can access the fb
608 	 * list any more, so no need to grab fpriv->fbs_lock. And we need to
609 	 * avoid upsetting lockdep since the universal cursor code adds a
610 	 * framebuffer while holding mutex locks.
611 	 *
612 	 * Note that a real deadlock between fpriv->fbs_lock and the modeset
613 	 * locks is impossible here since no one else but this function can get
614 	 * at it any more.
615 	 */
616 	list_for_each_entry_safe(fb, tfb, &priv->fbs, filp_head) {
617 		if (drm_framebuffer_read_refcount(fb) > 1) {
618 			list_move_tail(&fb->filp_head, &arg.fbs);
619 		} else {
620 			list_del_init(&fb->filp_head);
621 
622 			/* This drops the fpriv->fbs reference. */
623 			drm_framebuffer_put(fb);
624 		}
625 	}
626 
627 	if (!list_empty(&arg.fbs)) {
628 		INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);
629 
630 		schedule_work(&arg.work);
631 		flush_work(&arg.work);
632 		destroy_work_on_stack(&arg.work);
633 	}
634 }
635 
636 void drm_framebuffer_free(struct kref *kref)
637 {
638 	struct drm_framebuffer *fb =
639 			container_of(kref, struct drm_framebuffer, base.refcount);
640 	struct drm_device *dev = fb->dev;
641 
642 	/*
643 	 * The lookup idr holds a weak reference, which has not necessarily been
644 	 * removed at this point. Check for that.
645 	 */
646 	drm_mode_object_unregister(dev, &fb->base);
647 
648 	fb->funcs->destroy(fb);
649 }
650 
651 /**
652  * drm_framebuffer_init - initialize a framebuffer
653  * @dev: DRM device
654  * @fb: framebuffer to be initialized
655  * @funcs: ... with these functions
656  *
657  * Allocates an ID for the framebuffer's parent mode object, sets its mode
658  * functions & device file and adds it to the master fd list.
659  *
660  * IMPORTANT:
661  * This functions publishes the fb and makes it available for concurrent access
662  * by other users. Which means by this point the fb _must_ be fully set up -
663  * since all the fb attributes are invariant over its lifetime, no further
664  * locking but only correct reference counting is required.
665  *
666  * Returns:
667  * Zero on success, error code on failure.
668  */
669 int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
670 			 const struct drm_framebuffer_funcs *funcs)
671 {
672 	int ret;
673 
674 	if (WARN_ON_ONCE(fb->dev != dev || !fb->format))
675 		return -EINVAL;
676 
677 	INIT_LIST_HEAD(&fb->filp_head);
678 
679 	fb->funcs = funcs;
680 	strcpy(fb->comm, current->comm);
681 
682 	ret = __drm_mode_object_add(dev, &fb->base, DRM_MODE_OBJECT_FB,
683 				    false, drm_framebuffer_free);
684 	if (ret)
685 		goto out;
686 
687 	mutex_lock(&dev->mode_config.fb_lock);
688 	dev->mode_config.num_fb++;
689 	list_add(&fb->head, &dev->mode_config.fb_list);
690 	mutex_unlock(&dev->mode_config.fb_lock);
691 
692 	drm_mode_object_register(dev, &fb->base);
693 out:
694 	return ret;
695 }
696 EXPORT_SYMBOL(drm_framebuffer_init);
697 
698 /**
699  * drm_framebuffer_lookup - look up a drm framebuffer and grab a reference
700  * @dev: drm device
701  * @file_priv: drm file to check for lease against.
702  * @id: id of the fb object
703  *
704  * If successful, this grabs an additional reference to the framebuffer -
705  * callers need to make sure to eventually unreference the returned framebuffer
706  * again, using drm_framebuffer_put().
707  */
708 struct drm_framebuffer *drm_framebuffer_lookup(struct drm_device *dev,
709 					       struct drm_file *file_priv,
710 					       uint32_t id)
711 {
712 	struct drm_mode_object *obj;
713 	struct drm_framebuffer *fb = NULL;
714 
715 	obj = __drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_FB);
716 	if (obj)
717 		fb = obj_to_fb(obj);
718 	return fb;
719 }
720 EXPORT_SYMBOL(drm_framebuffer_lookup);
721 
722 /**
723  * drm_framebuffer_unregister_private - unregister a private fb from the lookup idr
724  * @fb: fb to unregister
725  *
726  * Drivers need to call this when cleaning up driver-private framebuffers, e.g.
727  * those used for fbdev. Note that the caller must hold a reference of it's own,
728  * i.e. the object may not be destroyed through this call (since it'll lead to a
729  * locking inversion).
730  *
731  * NOTE: This function is deprecated. For driver-private framebuffers it is not
732  * recommended to embed a framebuffer struct info fbdev struct, instead, a
733  * framebuffer pointer is preferred and drm_framebuffer_put() should be called
734  * when the framebuffer is to be cleaned up.
735  */
736 void drm_framebuffer_unregister_private(struct drm_framebuffer *fb)
737 {
738 	struct drm_device *dev;
739 
740 	if (!fb)
741 		return;
742 
743 	dev = fb->dev;
744 
745 	/* Mark fb as reaped and drop idr ref. */
746 	drm_mode_object_unregister(dev, &fb->base);
747 }
748 EXPORT_SYMBOL(drm_framebuffer_unregister_private);
749 
750 /**
751  * drm_framebuffer_cleanup - remove a framebuffer object
752  * @fb: framebuffer to remove
753  *
754  * Cleanup framebuffer. This function is intended to be used from the drivers
755  * &drm_framebuffer_funcs.destroy callback. It can also be used to clean up
756  * driver private framebuffers embedded into a larger structure.
757  *
758  * Note that this function does not remove the fb from active usage - if it is
759  * still used anywhere, hilarity can ensue since userspace could call getfb on
760  * the id and get back -EINVAL. Obviously no concern at driver unload time.
761  *
762  * Also, the framebuffer will not be removed from the lookup idr - for
763  * user-created framebuffers this will happen in in the rmfb ioctl. For
764  * driver-private objects (e.g. for fbdev) drivers need to explicitly call
765  * drm_framebuffer_unregister_private.
766  */
767 void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
768 {
769 	struct drm_device *dev = fb->dev;
770 
771 	mutex_lock(&dev->mode_config.fb_lock);
772 	list_del(&fb->head);
773 	dev->mode_config.num_fb--;
774 	mutex_unlock(&dev->mode_config.fb_lock);
775 }
776 EXPORT_SYMBOL(drm_framebuffer_cleanup);
777 
778 static int atomic_remove_fb(struct drm_framebuffer *fb)
779 {
780 	struct drm_modeset_acquire_ctx ctx;
781 	struct drm_device *dev = fb->dev;
782 	struct drm_atomic_state *state;
783 	struct drm_plane *plane;
784 	struct drm_connector *conn;
785 	struct drm_connector_state *conn_state;
786 	int i, ret;
787 	unsigned plane_mask;
788 	bool disable_crtcs = false;
789 
790 retry_disable:
791 	drm_modeset_acquire_init(&ctx, 0);
792 
793 	state = drm_atomic_state_alloc(dev);
794 	if (!state) {
795 		ret = -ENOMEM;
796 		goto out;
797 	}
798 	state->acquire_ctx = &ctx;
799 
800 retry:
801 	plane_mask = 0;
802 	ret = drm_modeset_lock_all_ctx(dev, &ctx);
803 	if (ret)
804 		goto unlock;
805 
806 	drm_for_each_plane(plane, dev) {
807 		struct drm_plane_state *plane_state;
808 
809 		if (plane->state->fb != fb)
810 			continue;
811 
812 		plane_state = drm_atomic_get_plane_state(state, plane);
813 		if (IS_ERR(plane_state)) {
814 			ret = PTR_ERR(plane_state);
815 			goto unlock;
816 		}
817 
818 		if (disable_crtcs && plane_state->crtc->primary == plane) {
819 			struct drm_crtc_state *crtc_state;
820 
821 			crtc_state = drm_atomic_get_existing_crtc_state(state, plane_state->crtc);
822 
823 			ret = drm_atomic_add_affected_connectors(state, plane_state->crtc);
824 			if (ret)
825 				goto unlock;
826 
827 			crtc_state->active = false;
828 			ret = drm_atomic_set_mode_for_crtc(crtc_state, NULL);
829 			if (ret)
830 				goto unlock;
831 		}
832 
833 		drm_atomic_set_fb_for_plane(plane_state, NULL);
834 		ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
835 		if (ret)
836 			goto unlock;
837 
838 		plane_mask |= BIT(drm_plane_index(plane));
839 
840 		plane->old_fb = plane->fb;
841 	}
842 
843 	/* This list is only filled when disable_crtcs is set. */
844 	for_each_new_connector_in_state(state, conn, conn_state, i) {
845 		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
846 
847 		if (ret)
848 			goto unlock;
849 	}
850 
851 	if (plane_mask)
852 		ret = drm_atomic_commit(state);
853 
854 unlock:
855 	if (plane_mask)
856 		drm_atomic_clean_old_fb(dev, plane_mask, ret);
857 
858 	if (ret == -EDEADLK) {
859 		drm_atomic_state_clear(state);
860 		drm_modeset_backoff(&ctx);
861 		goto retry;
862 	}
863 
864 	drm_atomic_state_put(state);
865 
866 out:
867 	drm_modeset_drop_locks(&ctx);
868 	drm_modeset_acquire_fini(&ctx);
869 
870 	if (ret == -EINVAL && !disable_crtcs) {
871 		disable_crtcs = true;
872 		goto retry_disable;
873 	}
874 
875 	return ret;
876 }
877 
878 static void legacy_remove_fb(struct drm_framebuffer *fb)
879 {
880 	struct drm_device *dev = fb->dev;
881 	struct drm_crtc *crtc;
882 	struct drm_plane *plane;
883 
884 	drm_modeset_lock_all(dev);
885 	/* remove from any CRTC */
886 	drm_for_each_crtc(crtc, dev) {
887 		if (crtc->primary->fb == fb) {
888 			/* should turn off the crtc */
889 			if (drm_crtc_force_disable(crtc))
890 				DRM_ERROR("failed to reset crtc %p when fb was deleted\n", crtc);
891 		}
892 	}
893 
894 	drm_for_each_plane(plane, dev) {
895 		if (plane->fb == fb)
896 			drm_plane_force_disable(plane);
897 	}
898 	drm_modeset_unlock_all(dev);
899 }
900 
901 /**
902  * drm_framebuffer_remove - remove and unreference a framebuffer object
903  * @fb: framebuffer to remove
904  *
905  * Scans all the CRTCs and planes in @dev's mode_config.  If they're
906  * using @fb, removes it, setting it to NULL. Then drops the reference to the
907  * passed-in framebuffer. Might take the modeset locks.
908  *
909  * Note that this function optimizes the cleanup away if the caller holds the
910  * last reference to the framebuffer. It is also guaranteed to not take the
911  * modeset locks in this case.
912  */
913 void drm_framebuffer_remove(struct drm_framebuffer *fb)
914 {
915 	struct drm_device *dev;
916 
917 	if (!fb)
918 		return;
919 
920 	dev = fb->dev;
921 
922 	WARN_ON(!list_empty(&fb->filp_head));
923 
924 	/*
925 	 * drm ABI mandates that we remove any deleted framebuffers from active
926 	 * useage. But since most sane clients only remove framebuffers they no
927 	 * longer need, try to optimize this away.
928 	 *
929 	 * Since we're holding a reference ourselves, observing a refcount of 1
930 	 * means that we're the last holder and can skip it. Also, the refcount
931 	 * can never increase from 1 again, so we don't need any barriers or
932 	 * locks.
933 	 *
934 	 * Note that userspace could try to race with use and instate a new
935 	 * usage _after_ we've cleared all current ones. End result will be an
936 	 * in-use fb with fb-id == 0. Userspace is allowed to shoot its own foot
937 	 * in this manner.
938 	 */
939 	if (drm_framebuffer_read_refcount(fb) > 1) {
940 		if (drm_drv_uses_atomic_modeset(dev)) {
941 			int ret = atomic_remove_fb(fb);
942 			WARN(ret, "atomic remove_fb failed with %i\n", ret);
943 		} else
944 			legacy_remove_fb(fb);
945 	}
946 
947 	drm_framebuffer_put(fb);
948 }
949 EXPORT_SYMBOL(drm_framebuffer_remove);
950 
951 /**
952  * drm_framebuffer_plane_width - width of the plane given the first plane
953  * @width: width of the first plane
954  * @fb: the framebuffer
955  * @plane: plane index
956  *
957  * Returns:
958  * The width of @plane, given that the width of the first plane is @width.
959  */
960 int drm_framebuffer_plane_width(int width,
961 				const struct drm_framebuffer *fb, int plane)
962 {
963 	if (plane >= fb->format->num_planes)
964 		return 0;
965 
966 	return fb_plane_width(width, fb->format, plane);
967 }
968 EXPORT_SYMBOL(drm_framebuffer_plane_width);
969 
970 /**
971  * drm_framebuffer_plane_height - height of the plane given the first plane
972  * @height: height of the first plane
973  * @fb: the framebuffer
974  * @plane: plane index
975  *
976  * Returns:
977  * The height of @plane, given that the height of the first plane is @height.
978  */
979 int drm_framebuffer_plane_height(int height,
980 				 const struct drm_framebuffer *fb, int plane)
981 {
982 	if (plane >= fb->format->num_planes)
983 		return 0;
984 
985 	return fb_plane_height(height, fb->format, plane);
986 }
987 EXPORT_SYMBOL(drm_framebuffer_plane_height);
988 
989 void drm_framebuffer_print_info(struct drm_printer *p, unsigned int indent,
990 				const struct drm_framebuffer *fb)
991 {
992 	struct drm_format_name_buf format_name;
993 	unsigned int i;
994 
995 	drm_printf_indent(p, indent, "allocated by = %s\n", fb->comm);
996 	drm_printf_indent(p, indent, "refcount=%u\n",
997 			  drm_framebuffer_read_refcount(fb));
998 	drm_printf_indent(p, indent, "format=%s\n",
999 			  drm_get_format_name(fb->format->format, &format_name));
1000 	drm_printf_indent(p, indent, "modifier=0x%llx\n", fb->modifier);
1001 	drm_printf_indent(p, indent, "size=%ux%u\n", fb->width, fb->height);
1002 	drm_printf_indent(p, indent, "layers:\n");
1003 
1004 	for (i = 0; i < fb->format->num_planes; i++) {
1005 		drm_printf_indent(p, indent + 1, "size[%u]=%dx%d\n", i,
1006 				  drm_framebuffer_plane_width(fb->width, fb, i),
1007 				  drm_framebuffer_plane_height(fb->height, fb, i));
1008 		drm_printf_indent(p, indent + 1, "pitch[%u]=%u\n", i, fb->pitches[i]);
1009 		drm_printf_indent(p, indent + 1, "offset[%u]=%u\n", i, fb->offsets[i]);
1010 		drm_printf_indent(p, indent + 1, "obj[%u]:%s\n", i,
1011 				  fb->obj[i] ? "" : "(null)");
1012 		if (fb->obj[i])
1013 			drm_gem_print_info(p, indent + 2, fb->obj[i]);
1014 	}
1015 }
1016 
1017 #ifdef CONFIG_DEBUG_FS
1018 static int drm_framebuffer_info(struct seq_file *m, void *data)
1019 {
1020 	struct drm_info_node *node = m->private;
1021 	struct drm_device *dev = node->minor->dev;
1022 	struct drm_printer p = drm_seq_file_printer(m);
1023 	struct drm_framebuffer *fb;
1024 
1025 	mutex_lock(&dev->mode_config.fb_lock);
1026 	drm_for_each_fb(fb, dev) {
1027 		drm_printf(&p, "framebuffer[%u]:\n", fb->base.id);
1028 		drm_framebuffer_print_info(&p, 1, fb);
1029 	}
1030 	mutex_unlock(&dev->mode_config.fb_lock);
1031 
1032 	return 0;
1033 }
1034 
1035 static const struct drm_info_list drm_framebuffer_debugfs_list[] = {
1036 	{ "framebuffer", drm_framebuffer_info, 0 },
1037 };
1038 
1039 int drm_framebuffer_debugfs_init(struct drm_minor *minor)
1040 {
1041 	return drm_debugfs_create_files(drm_framebuffer_debugfs_list,
1042 				ARRAY_SIZE(drm_framebuffer_debugfs_list),
1043 				minor->debugfs_root, minor);
1044 }
1045 #endif
1046