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 <linux/uaccess.h>
25 
26 #include <drm/drm_atomic.h>
27 #include <drm/drm_atomic_uapi.h>
28 #include <drm/drm_auth.h>
29 #include <drm/drm_debugfs.h>
30 #include <drm/drm_drv.h>
31 #include <drm/drm_file.h>
32 #include <drm/drm_fourcc.h>
33 #include <drm/drm_framebuffer.h>
34 #include <drm/drm_gem.h>
35 #include <drm/drm_print.h>
36 #include <drm/drm_util.h>
37 
38 #include "drm_crtc_internal.h"
39 #include "drm_internal.h"
40 
41 /**
42  * DOC: overview
43  *
44  * Frame buffers are abstract memory objects that provide a source of pixels to
45  * scanout to a CRTC. Applications explicitly request the creation of frame
46  * buffers through the DRM_IOCTL_MODE_ADDFB(2) ioctls and receive an opaque
47  * handle that can be passed to the KMS CRTC control, plane configuration and
48  * page flip functions.
49  *
50  * Frame buffers rely on the underlying memory manager for allocating backing
51  * storage. When creating a frame buffer applications pass a memory handle
52  * (or a list of memory handles for multi-planar formats) through the
53  * &struct drm_mode_fb_cmd2 argument. For drivers using GEM as their userspace
54  * buffer management interface this would be a GEM handle.  Drivers are however
55  * free to use their own backing storage object handles, e.g. vmwgfx directly
56  * exposes special TTM handles to userspace and so expects TTM handles in the
57  * create ioctl and not GEM handles.
58  *
59  * Framebuffers are tracked with &struct drm_framebuffer. They are published
60  * using drm_framebuffer_init() - after calling that function userspace can use
61  * and access the framebuffer object. The helper function
62  * drm_helper_mode_fill_fb_struct() can be used to pre-fill the required
63  * metadata fields.
64  *
65  * The lifetime of a drm framebuffer is controlled with a reference count,
66  * drivers can grab additional references with drm_framebuffer_get() and drop
67  * them again with drm_framebuffer_put(). For driver-private framebuffers for
68  * which the last reference is never dropped (e.g. for the fbdev framebuffer
69  * when the struct &struct drm_framebuffer is embedded into the fbdev helper
70  * struct) drivers can manually clean up a framebuffer at module unload time
71  * with drm_framebuffer_unregister_private(). But doing this is not
72  * recommended, and it's better to have a normal free-standing &struct
73  * drm_framebuffer.
74  */
75 
76 int drm_framebuffer_check_src_coords(uint32_t src_x, uint32_t src_y,
77 				     uint32_t src_w, uint32_t src_h,
78 				     const struct drm_framebuffer *fb)
79 {
80 	unsigned int fb_width, fb_height;
81 
82 	fb_width = fb->width << 16;
83 	fb_height = fb->height << 16;
84 
85 	/* Make sure source coordinates are inside the fb. */
86 	if (src_w > fb_width ||
87 	    src_x > fb_width - src_w ||
88 	    src_h > fb_height ||
89 	    src_y > fb_height - src_h) {
90 		drm_dbg_kms(fb->dev, "Invalid source coordinates "
91 			    "%u.%06ux%u.%06u+%u.%06u+%u.%06u (fb %ux%u)\n",
92 			    src_w >> 16, ((src_w & 0xffff) * 15625) >> 10,
93 			    src_h >> 16, ((src_h & 0xffff) * 15625) >> 10,
94 			    src_x >> 16, ((src_x & 0xffff) * 15625) >> 10,
95 			    src_y >> 16, ((src_y & 0xffff) * 15625) >> 10,
96 			    fb->width, fb->height);
97 		return -ENOSPC;
98 	}
99 
100 	return 0;
101 }
102 
103 /**
104  * drm_mode_addfb - add an FB to the graphics configuration
105  * @dev: drm device for the ioctl
106  * @or: pointer to request structure
107  * @file_priv: drm file
108  *
109  * Add a new FB to the specified CRTC, given a user request. This is the
110  * original addfb ioctl which only supported RGB formats.
111  *
112  * Called by the user via ioctl, or by an in-kernel client.
113  *
114  * Returns:
115  * Zero on success, negative errno on failure.
116  */
117 int drm_mode_addfb(struct drm_device *dev, struct drm_mode_fb_cmd *or,
118 		   struct drm_file *file_priv)
119 {
120 	struct drm_mode_fb_cmd2 r = {};
121 	int ret;
122 
123 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
124 		return -EOPNOTSUPP;
125 
126 	r.pixel_format = drm_driver_legacy_fb_format(dev, or->bpp, or->depth);
127 	if (r.pixel_format == DRM_FORMAT_INVALID) {
128 		drm_dbg_kms(dev, "bad {bpp:%d, depth:%d}\n", or->bpp, or->depth);
129 		return -EINVAL;
130 	}
131 
132 	/* convert to new format and call new ioctl */
133 	r.fb_id = or->fb_id;
134 	r.width = or->width;
135 	r.height = or->height;
136 	r.pitches[0] = or->pitch;
137 	r.handles[0] = or->handle;
138 
139 	ret = drm_mode_addfb2(dev, &r, file_priv);
140 	if (ret)
141 		return ret;
142 
143 	or->fb_id = r.fb_id;
144 
145 	return 0;
146 }
147 
148 int drm_mode_addfb_ioctl(struct drm_device *dev,
149 			 void *data, struct drm_file *file_priv)
150 {
151 	return drm_mode_addfb(dev, data, file_priv);
152 }
153 
154 static int fb_plane_width(int width,
155 			  const struct drm_format_info *format, int plane)
156 {
157 	if (plane == 0)
158 		return width;
159 
160 	return DIV_ROUND_UP(width, format->hsub);
161 }
162 
163 static int fb_plane_height(int height,
164 			   const struct drm_format_info *format, int plane)
165 {
166 	if (plane == 0)
167 		return height;
168 
169 	return DIV_ROUND_UP(height, format->vsub);
170 }
171 
172 static int framebuffer_check(struct drm_device *dev,
173 			     const struct drm_mode_fb_cmd2 *r)
174 {
175 	const struct drm_format_info *info;
176 	int i;
177 
178 	/* check if the format is supported at all */
179 	if (!__drm_format_info(r->pixel_format)) {
180 		drm_dbg_kms(dev, "bad framebuffer format %p4cc\n",
181 			    &r->pixel_format);
182 		return -EINVAL;
183 	}
184 
185 	if (r->width == 0) {
186 		drm_dbg_kms(dev, "bad framebuffer width %u\n", r->width);
187 		return -EINVAL;
188 	}
189 
190 	if (r->height == 0) {
191 		drm_dbg_kms(dev, "bad framebuffer height %u\n", r->height);
192 		return -EINVAL;
193 	}
194 
195 	/* now let the driver pick its own format info */
196 	info = drm_get_format_info(dev, r);
197 
198 	for (i = 0; i < info->num_planes; i++) {
199 		unsigned int width = fb_plane_width(r->width, info, i);
200 		unsigned int height = fb_plane_height(r->height, info, i);
201 		unsigned int block_size = info->char_per_block[i];
202 		u64 min_pitch = drm_format_info_min_pitch(info, i, width);
203 
204 		if (!block_size && (r->modifier[i] == DRM_FORMAT_MOD_LINEAR)) {
205 			drm_dbg_kms(dev, "Format requires non-linear modifier for plane %d\n", i);
206 			return -EINVAL;
207 		}
208 
209 		if (!r->handles[i]) {
210 			drm_dbg_kms(dev, "no buffer object handle for plane %d\n", i);
211 			return -EINVAL;
212 		}
213 
214 		if (min_pitch > UINT_MAX)
215 			return -ERANGE;
216 
217 		if ((uint64_t) height * r->pitches[i] + r->offsets[i] > UINT_MAX)
218 			return -ERANGE;
219 
220 		if (block_size && r->pitches[i] < min_pitch) {
221 			drm_dbg_kms(dev, "bad pitch %u for plane %d\n", r->pitches[i], i);
222 			return -EINVAL;
223 		}
224 
225 		if (r->modifier[i] && !(r->flags & DRM_MODE_FB_MODIFIERS)) {
226 			drm_dbg_kms(dev, "bad fb modifier %llu for plane %d\n",
227 				    r->modifier[i], i);
228 			return -EINVAL;
229 		}
230 
231 		if (r->flags & DRM_MODE_FB_MODIFIERS &&
232 		    r->modifier[i] != r->modifier[0]) {
233 			drm_dbg_kms(dev, "bad fb modifier %llu for plane %d\n",
234 				    r->modifier[i], i);
235 			return -EINVAL;
236 		}
237 
238 		/* modifier specific checks: */
239 		switch (r->modifier[i]) {
240 		case DRM_FORMAT_MOD_SAMSUNG_64_32_TILE:
241 			/* NOTE: the pitch restriction may be lifted later if it turns
242 			 * out that no hw has this restriction:
243 			 */
244 			if (r->pixel_format != DRM_FORMAT_NV12 ||
245 					width % 128 || height % 32 ||
246 					r->pitches[i] % 128) {
247 				drm_dbg_kms(dev, "bad modifier data for plane %d\n", i);
248 				return -EINVAL;
249 			}
250 			break;
251 
252 		default:
253 			break;
254 		}
255 	}
256 
257 	for (i = info->num_planes; i < 4; i++) {
258 		if (r->modifier[i]) {
259 			drm_dbg_kms(dev, "non-zero modifier for unused plane %d\n", i);
260 			return -EINVAL;
261 		}
262 
263 		/* Pre-FB_MODIFIERS userspace didn't clear the structs properly. */
264 		if (!(r->flags & DRM_MODE_FB_MODIFIERS))
265 			continue;
266 
267 		if (r->handles[i]) {
268 			drm_dbg_kms(dev, "buffer object handle for unused plane %d\n", i);
269 			return -EINVAL;
270 		}
271 
272 		if (r->pitches[i]) {
273 			drm_dbg_kms(dev, "non-zero pitch for unused plane %d\n", i);
274 			return -EINVAL;
275 		}
276 
277 		if (r->offsets[i]) {
278 			drm_dbg_kms(dev, "non-zero offset for unused plane %d\n", i);
279 			return -EINVAL;
280 		}
281 	}
282 
283 	return 0;
284 }
285 
286 struct drm_framebuffer *
287 drm_internal_framebuffer_create(struct drm_device *dev,
288 				const struct drm_mode_fb_cmd2 *r,
289 				struct drm_file *file_priv)
290 {
291 	struct drm_mode_config *config = &dev->mode_config;
292 	struct drm_framebuffer *fb;
293 	int ret;
294 
295 	if (r->flags & ~(DRM_MODE_FB_INTERLACED | DRM_MODE_FB_MODIFIERS)) {
296 		drm_dbg_kms(dev, "bad framebuffer flags 0x%08x\n", r->flags);
297 		return ERR_PTR(-EINVAL);
298 	}
299 
300 	if ((config->min_width > r->width) || (r->width > config->max_width)) {
301 		drm_dbg_kms(dev, "bad framebuffer width %d, should be >= %d && <= %d\n",
302 			    r->width, config->min_width, config->max_width);
303 		return ERR_PTR(-EINVAL);
304 	}
305 	if ((config->min_height > r->height) || (r->height > config->max_height)) {
306 		drm_dbg_kms(dev, "bad framebuffer height %d, should be >= %d && <= %d\n",
307 			    r->height, config->min_height, config->max_height);
308 		return ERR_PTR(-EINVAL);
309 	}
310 
311 	if (r->flags & DRM_MODE_FB_MODIFIERS &&
312 	    dev->mode_config.fb_modifiers_not_supported) {
313 		drm_dbg_kms(dev, "driver does not support fb modifiers\n");
314 		return ERR_PTR(-EINVAL);
315 	}
316 
317 	ret = framebuffer_check(dev, r);
318 	if (ret)
319 		return ERR_PTR(ret);
320 
321 	fb = dev->mode_config.funcs->fb_create(dev, file_priv, r);
322 	if (IS_ERR(fb)) {
323 		drm_dbg_kms(dev, "could not create framebuffer\n");
324 		return fb;
325 	}
326 
327 	return fb;
328 }
329 EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_internal_framebuffer_create);
330 
331 /**
332  * drm_mode_addfb2 - add an FB to the graphics configuration
333  * @dev: drm device for the ioctl
334  * @data: data pointer for the ioctl
335  * @file_priv: drm file for the ioctl call
336  *
337  * Add a new FB to the specified CRTC, given a user request with format. This is
338  * the 2nd version of the addfb ioctl, which supports multi-planar framebuffers
339  * and uses fourcc codes as pixel format specifiers.
340  *
341  * Called by the user via ioctl.
342  *
343  * Returns:
344  * Zero on success, negative errno on failure.
345  */
346 int drm_mode_addfb2(struct drm_device *dev,
347 		    void *data, struct drm_file *file_priv)
348 {
349 	struct drm_mode_fb_cmd2 *r = data;
350 	struct drm_framebuffer *fb;
351 
352 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
353 		return -EOPNOTSUPP;
354 
355 	fb = drm_internal_framebuffer_create(dev, r, file_priv);
356 	if (IS_ERR(fb))
357 		return PTR_ERR(fb);
358 
359 	drm_dbg_kms(dev, "[FB:%d]\n", fb->base.id);
360 	r->fb_id = fb->base.id;
361 
362 	/* Transfer ownership to the filp for reaping on close */
363 	mutex_lock(&file_priv->fbs_lock);
364 	list_add(&fb->filp_head, &file_priv->fbs);
365 	mutex_unlock(&file_priv->fbs_lock);
366 
367 	return 0;
368 }
369 
370 int drm_mode_addfb2_ioctl(struct drm_device *dev,
371 			  void *data, struct drm_file *file_priv)
372 {
373 #ifdef __BIG_ENDIAN
374 	if (!dev->mode_config.quirk_addfb_prefer_host_byte_order) {
375 		/*
376 		 * Drivers must set the
377 		 * quirk_addfb_prefer_host_byte_order quirk to make
378 		 * the drm_mode_addfb() compat code work correctly on
379 		 * bigendian machines.
380 		 *
381 		 * If they don't they interpret pixel_format values
382 		 * incorrectly for bug compatibility, which in turn
383 		 * implies the ADDFB2 ioctl does not work correctly
384 		 * then.  So block it to make userspace fallback to
385 		 * ADDFB.
386 		 */
387 		drm_dbg_kms(dev, "addfb2 broken on bigendian");
388 		return -EOPNOTSUPP;
389 	}
390 #endif
391 	return drm_mode_addfb2(dev, data, file_priv);
392 }
393 
394 struct drm_mode_rmfb_work {
395 	struct work_struct work;
396 	struct list_head fbs;
397 };
398 
399 static void drm_mode_rmfb_work_fn(struct work_struct *w)
400 {
401 	struct drm_mode_rmfb_work *arg = container_of(w, typeof(*arg), work);
402 
403 	while (!list_empty(&arg->fbs)) {
404 		struct drm_framebuffer *fb =
405 			list_first_entry(&arg->fbs, typeof(*fb), filp_head);
406 
407 		drm_dbg_kms(fb->dev,
408 			    "Removing [FB:%d] from all active usage due to RMFB ioctl\n",
409 			    fb->base.id);
410 		list_del_init(&fb->filp_head);
411 		drm_framebuffer_remove(fb);
412 	}
413 }
414 
415 /**
416  * drm_mode_rmfb - remove an FB from the configuration
417  * @dev: drm device
418  * @fb_id: id of framebuffer to remove
419  * @file_priv: drm file
420  *
421  * Remove the specified FB.
422  *
423  * Called by the user via ioctl, or by an in-kernel client.
424  *
425  * Returns:
426  * Zero on success, negative errno on failure.
427  */
428 int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,
429 		  struct drm_file *file_priv)
430 {
431 	struct drm_framebuffer *fb = NULL;
432 	struct drm_framebuffer *fbl = NULL;
433 	int found = 0;
434 
435 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
436 		return -EOPNOTSUPP;
437 
438 	fb = drm_framebuffer_lookup(dev, file_priv, fb_id);
439 	if (!fb)
440 		return -ENOENT;
441 
442 	mutex_lock(&file_priv->fbs_lock);
443 	list_for_each_entry(fbl, &file_priv->fbs, filp_head)
444 		if (fb == fbl)
445 			found = 1;
446 	if (!found) {
447 		mutex_unlock(&file_priv->fbs_lock);
448 		goto fail_unref;
449 	}
450 
451 	list_del_init(&fb->filp_head);
452 	mutex_unlock(&file_priv->fbs_lock);
453 
454 	/* drop the reference we picked up in framebuffer lookup */
455 	drm_framebuffer_put(fb);
456 
457 	/*
458 	 * we now own the reference that was stored in the fbs list
459 	 *
460 	 * drm_framebuffer_remove may fail with -EINTR on pending signals,
461 	 * so run this in a separate stack as there's no way to correctly
462 	 * handle this after the fb is already removed from the lookup table.
463 	 */
464 	if (drm_framebuffer_read_refcount(fb) > 1) {
465 		struct drm_mode_rmfb_work arg;
466 
467 		INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);
468 		INIT_LIST_HEAD(&arg.fbs);
469 		list_add_tail(&fb->filp_head, &arg.fbs);
470 
471 		schedule_work(&arg.work);
472 		flush_work(&arg.work);
473 		destroy_work_on_stack(&arg.work);
474 	} else
475 		drm_framebuffer_put(fb);
476 
477 	return 0;
478 
479 fail_unref:
480 	drm_framebuffer_put(fb);
481 	return -ENOENT;
482 }
483 
484 int drm_mode_rmfb_ioctl(struct drm_device *dev,
485 			void *data, struct drm_file *file_priv)
486 {
487 	uint32_t *fb_id = data;
488 
489 	return drm_mode_rmfb(dev, *fb_id, file_priv);
490 }
491 
492 /**
493  * drm_mode_getfb - get FB info
494  * @dev: drm device for the ioctl
495  * @data: data pointer for the ioctl
496  * @file_priv: drm file for the ioctl call
497  *
498  * Lookup the FB given its ID and return info about it.
499  *
500  * Called by the user via ioctl.
501  *
502  * Returns:
503  * Zero on success, negative errno on failure.
504  */
505 int drm_mode_getfb(struct drm_device *dev,
506 		   void *data, struct drm_file *file_priv)
507 {
508 	struct drm_mode_fb_cmd *r = data;
509 	struct drm_framebuffer *fb;
510 	int ret;
511 
512 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
513 		return -EOPNOTSUPP;
514 
515 	fb = drm_framebuffer_lookup(dev, file_priv, r->fb_id);
516 	if (!fb)
517 		return -ENOENT;
518 
519 	/* Multi-planar framebuffers need getfb2. */
520 	if (fb->format->num_planes > 1) {
521 		ret = -EINVAL;
522 		goto out;
523 	}
524 
525 	if (!fb->funcs->create_handle) {
526 		ret = -ENODEV;
527 		goto out;
528 	}
529 
530 	r->height = fb->height;
531 	r->width = fb->width;
532 	r->depth = fb->format->depth;
533 	r->bpp = drm_format_info_bpp(fb->format, 0);
534 	r->pitch = fb->pitches[0];
535 
536 	/* GET_FB() is an unprivileged ioctl so we must not return a
537 	 * buffer-handle to non-master processes! For
538 	 * backwards-compatibility reasons, we cannot make GET_FB() privileged,
539 	 * so just return an invalid handle for non-masters.
540 	 */
541 	if (!drm_is_current_master(file_priv) && !capable(CAP_SYS_ADMIN)) {
542 		r->handle = 0;
543 		ret = 0;
544 		goto out;
545 	}
546 
547 	ret = fb->funcs->create_handle(fb, file_priv, &r->handle);
548 
549 out:
550 	drm_framebuffer_put(fb);
551 	return ret;
552 }
553 
554 /**
555  * drm_mode_getfb2_ioctl - get extended FB info
556  * @dev: drm device for the ioctl
557  * @data: data pointer for the ioctl
558  * @file_priv: drm file for the ioctl call
559  *
560  * Lookup the FB given its ID and return info about it.
561  *
562  * Called by the user via ioctl.
563  *
564  * Returns:
565  * Zero on success, negative errno on failure.
566  */
567 int drm_mode_getfb2_ioctl(struct drm_device *dev,
568 			  void *data, struct drm_file *file_priv)
569 {
570 	struct drm_mode_fb_cmd2 *r = data;
571 	struct drm_framebuffer *fb;
572 	unsigned int i;
573 	int ret;
574 
575 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
576 		return -EINVAL;
577 
578 	fb = drm_framebuffer_lookup(dev, file_priv, r->fb_id);
579 	if (!fb)
580 		return -ENOENT;
581 
582 	/* For multi-plane framebuffers, we require the driver to place the
583 	 * GEM objects directly in the drm_framebuffer. For single-plane
584 	 * framebuffers, we can fall back to create_handle.
585 	 */
586 	if (!fb->obj[0] &&
587 	    (fb->format->num_planes > 1 || !fb->funcs->create_handle)) {
588 		ret = -ENODEV;
589 		goto out;
590 	}
591 
592 	r->height = fb->height;
593 	r->width = fb->width;
594 	r->pixel_format = fb->format->format;
595 
596 	r->flags = 0;
597 	if (!dev->mode_config.fb_modifiers_not_supported)
598 		r->flags |= DRM_MODE_FB_MODIFIERS;
599 
600 	for (i = 0; i < ARRAY_SIZE(r->handles); i++) {
601 		r->handles[i] = 0;
602 		r->pitches[i] = 0;
603 		r->offsets[i] = 0;
604 		r->modifier[i] = 0;
605 	}
606 
607 	for (i = 0; i < fb->format->num_planes; i++) {
608 		r->pitches[i] = fb->pitches[i];
609 		r->offsets[i] = fb->offsets[i];
610 		if (!dev->mode_config.fb_modifiers_not_supported)
611 			r->modifier[i] = fb->modifier;
612 	}
613 
614 	/* GET_FB2() is an unprivileged ioctl so we must not return a
615 	 * buffer-handle to non master/root processes! To match GET_FB()
616 	 * just return invalid handles (0) for non masters/root
617 	 * rather than making GET_FB2() privileged.
618 	 */
619 	if (!drm_is_current_master(file_priv) && !capable(CAP_SYS_ADMIN)) {
620 		ret = 0;
621 		goto out;
622 	}
623 
624 	for (i = 0; i < fb->format->num_planes; i++) {
625 		int j;
626 
627 		/* If we reuse the same object for multiple planes, also
628 		 * return the same handle.
629 		 */
630 		for (j = 0; j < i; j++) {
631 			if (fb->obj[i] == fb->obj[j]) {
632 				r->handles[i] = r->handles[j];
633 				break;
634 			}
635 		}
636 
637 		if (r->handles[i])
638 			continue;
639 
640 		if (fb->obj[i]) {
641 			ret = drm_gem_handle_create(file_priv, fb->obj[i],
642 						    &r->handles[i]);
643 		} else {
644 			WARN_ON(i > 0);
645 			ret = fb->funcs->create_handle(fb, file_priv,
646 						       &r->handles[i]);
647 		}
648 
649 		if (ret != 0)
650 			goto out;
651 	}
652 
653 out:
654 	if (ret != 0) {
655 		/* Delete any previously-created handles on failure. */
656 		for (i = 0; i < ARRAY_SIZE(r->handles); i++) {
657 			int j;
658 
659 			if (r->handles[i])
660 				drm_gem_handle_delete(file_priv, r->handles[i]);
661 
662 			/* Zero out any handles identical to the one we just
663 			 * deleted.
664 			 */
665 			for (j = i + 1; j < ARRAY_SIZE(r->handles); j++) {
666 				if (r->handles[j] == r->handles[i])
667 					r->handles[j] = 0;
668 			}
669 		}
670 	}
671 
672 	drm_framebuffer_put(fb);
673 	return ret;
674 }
675 
676 /**
677  * drm_mode_dirtyfb_ioctl - flush frontbuffer rendering on an FB
678  * @dev: drm device for the ioctl
679  * @data: data pointer for the ioctl
680  * @file_priv: drm file for the ioctl call
681  *
682  * Lookup the FB and flush out the damaged area supplied by userspace as a clip
683  * rectangle list. Generic userspace which does frontbuffer rendering must call
684  * this ioctl to flush out the changes on manual-update display outputs, e.g.
685  * usb display-link, mipi manual update panels or edp panel self refresh modes.
686  *
687  * Modesetting drivers which always update the frontbuffer do not need to
688  * implement the corresponding &drm_framebuffer_funcs.dirty callback.
689  *
690  * Called by the user via ioctl.
691  *
692  * Returns:
693  * Zero on success, negative errno on failure.
694  */
695 int drm_mode_dirtyfb_ioctl(struct drm_device *dev,
696 			   void *data, struct drm_file *file_priv)
697 {
698 	struct drm_clip_rect __user *clips_ptr;
699 	struct drm_clip_rect *clips = NULL;
700 	struct drm_mode_fb_dirty_cmd *r = data;
701 	struct drm_framebuffer *fb;
702 	unsigned flags;
703 	int num_clips;
704 	int ret;
705 
706 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
707 		return -EOPNOTSUPP;
708 
709 	fb = drm_framebuffer_lookup(dev, file_priv, r->fb_id);
710 	if (!fb)
711 		return -ENOENT;
712 
713 	num_clips = r->num_clips;
714 	clips_ptr = (struct drm_clip_rect __user *)(unsigned long)r->clips_ptr;
715 
716 	if (!num_clips != !clips_ptr) {
717 		ret = -EINVAL;
718 		goto out_err1;
719 	}
720 
721 	flags = DRM_MODE_FB_DIRTY_FLAGS & r->flags;
722 
723 	/* If userspace annotates copy, clips must come in pairs */
724 	if (flags & DRM_MODE_FB_DIRTY_ANNOTATE_COPY && (num_clips % 2)) {
725 		ret = -EINVAL;
726 		goto out_err1;
727 	}
728 
729 	if (num_clips && clips_ptr) {
730 		if (num_clips < 0 || num_clips > DRM_MODE_FB_DIRTY_MAX_CLIPS) {
731 			ret = -EINVAL;
732 			goto out_err1;
733 		}
734 		clips = kcalloc(num_clips, sizeof(*clips), GFP_KERNEL);
735 		if (!clips) {
736 			ret = -ENOMEM;
737 			goto out_err1;
738 		}
739 
740 		ret = copy_from_user(clips, clips_ptr,
741 				     num_clips * sizeof(*clips));
742 		if (ret) {
743 			ret = -EFAULT;
744 			goto out_err2;
745 		}
746 	}
747 
748 	if (fb->funcs->dirty) {
749 		ret = fb->funcs->dirty(fb, file_priv, flags, r->color,
750 				       clips, num_clips);
751 	} else {
752 		ret = -ENOSYS;
753 	}
754 
755 out_err2:
756 	kfree(clips);
757 out_err1:
758 	drm_framebuffer_put(fb);
759 
760 	return ret;
761 }
762 
763 /**
764  * drm_fb_release - remove and free the FBs on this file
765  * @priv: drm file for the ioctl
766  *
767  * Destroy all the FBs associated with @filp.
768  *
769  * Called by the user via ioctl.
770  *
771  * Returns:
772  * Zero on success, negative errno on failure.
773  */
774 void drm_fb_release(struct drm_file *priv)
775 {
776 	struct drm_framebuffer *fb, *tfb;
777 	struct drm_mode_rmfb_work arg;
778 
779 	INIT_LIST_HEAD(&arg.fbs);
780 
781 	/*
782 	 * When the file gets released that means no one else can access the fb
783 	 * list any more, so no need to grab fpriv->fbs_lock. And we need to
784 	 * avoid upsetting lockdep since the universal cursor code adds a
785 	 * framebuffer while holding mutex locks.
786 	 *
787 	 * Note that a real deadlock between fpriv->fbs_lock and the modeset
788 	 * locks is impossible here since no one else but this function can get
789 	 * at it any more.
790 	 */
791 	list_for_each_entry_safe(fb, tfb, &priv->fbs, filp_head) {
792 		if (drm_framebuffer_read_refcount(fb) > 1) {
793 			list_move_tail(&fb->filp_head, &arg.fbs);
794 		} else {
795 			list_del_init(&fb->filp_head);
796 
797 			/* This drops the fpriv->fbs reference. */
798 			drm_framebuffer_put(fb);
799 		}
800 	}
801 
802 	if (!list_empty(&arg.fbs)) {
803 		INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);
804 
805 		schedule_work(&arg.work);
806 		flush_work(&arg.work);
807 		destroy_work_on_stack(&arg.work);
808 	}
809 }
810 
811 void drm_framebuffer_free(struct kref *kref)
812 {
813 	struct drm_framebuffer *fb =
814 			container_of(kref, struct drm_framebuffer, base.refcount);
815 	struct drm_device *dev = fb->dev;
816 
817 	/*
818 	 * The lookup idr holds a weak reference, which has not necessarily been
819 	 * removed at this point. Check for that.
820 	 */
821 	drm_mode_object_unregister(dev, &fb->base);
822 
823 	fb->funcs->destroy(fb);
824 }
825 
826 /**
827  * drm_framebuffer_init - initialize a framebuffer
828  * @dev: DRM device
829  * @fb: framebuffer to be initialized
830  * @funcs: ... with these functions
831  *
832  * Allocates an ID for the framebuffer's parent mode object, sets its mode
833  * functions & device file and adds it to the master fd list.
834  *
835  * IMPORTANT:
836  * This functions publishes the fb and makes it available for concurrent access
837  * by other users. Which means by this point the fb _must_ be fully set up -
838  * since all the fb attributes are invariant over its lifetime, no further
839  * locking but only correct reference counting is required.
840  *
841  * Returns:
842  * Zero on success, error code on failure.
843  */
844 int drm_framebuffer_init(struct drm_device *dev, struct drm_framebuffer *fb,
845 			 const struct drm_framebuffer_funcs *funcs)
846 {
847 	int ret;
848 
849 	if (WARN_ON_ONCE(fb->dev != dev || !fb->format))
850 		return -EINVAL;
851 
852 	INIT_LIST_HEAD(&fb->filp_head);
853 
854 	fb->funcs = funcs;
855 	strcpy(fb->comm, current->comm);
856 
857 	ret = __drm_mode_object_add(dev, &fb->base, DRM_MODE_OBJECT_FB,
858 				    false, drm_framebuffer_free);
859 	if (ret)
860 		goto out;
861 
862 	mutex_lock(&dev->mode_config.fb_lock);
863 	dev->mode_config.num_fb++;
864 	list_add(&fb->head, &dev->mode_config.fb_list);
865 	mutex_unlock(&dev->mode_config.fb_lock);
866 
867 	drm_mode_object_register(dev, &fb->base);
868 out:
869 	return ret;
870 }
871 EXPORT_SYMBOL(drm_framebuffer_init);
872 
873 /**
874  * drm_framebuffer_lookup - look up a drm framebuffer and grab a reference
875  * @dev: drm device
876  * @file_priv: drm file to check for lease against.
877  * @id: id of the fb object
878  *
879  * If successful, this grabs an additional reference to the framebuffer -
880  * callers need to make sure to eventually unreference the returned framebuffer
881  * again, using drm_framebuffer_put().
882  */
883 struct drm_framebuffer *drm_framebuffer_lookup(struct drm_device *dev,
884 					       struct drm_file *file_priv,
885 					       uint32_t id)
886 {
887 	struct drm_mode_object *obj;
888 	struct drm_framebuffer *fb = NULL;
889 
890 	obj = __drm_mode_object_find(dev, file_priv, id, DRM_MODE_OBJECT_FB);
891 	if (obj)
892 		fb = obj_to_fb(obj);
893 	return fb;
894 }
895 EXPORT_SYMBOL(drm_framebuffer_lookup);
896 
897 /**
898  * drm_framebuffer_unregister_private - unregister a private fb from the lookup idr
899  * @fb: fb to unregister
900  *
901  * Drivers need to call this when cleaning up driver-private framebuffers, e.g.
902  * those used for fbdev. Note that the caller must hold a reference of its own,
903  * i.e. the object may not be destroyed through this call (since it'll lead to a
904  * locking inversion).
905  *
906  * NOTE: This function is deprecated. For driver-private framebuffers it is not
907  * recommended to embed a framebuffer struct info fbdev struct, instead, a
908  * framebuffer pointer is preferred and drm_framebuffer_put() should be called
909  * when the framebuffer is to be cleaned up.
910  */
911 void drm_framebuffer_unregister_private(struct drm_framebuffer *fb)
912 {
913 	struct drm_device *dev;
914 
915 	if (!fb)
916 		return;
917 
918 	dev = fb->dev;
919 
920 	/* Mark fb as reaped and drop idr ref. */
921 	drm_mode_object_unregister(dev, &fb->base);
922 }
923 EXPORT_SYMBOL(drm_framebuffer_unregister_private);
924 
925 /**
926  * drm_framebuffer_cleanup - remove a framebuffer object
927  * @fb: framebuffer to remove
928  *
929  * Cleanup framebuffer. This function is intended to be used from the drivers
930  * &drm_framebuffer_funcs.destroy callback. It can also be used to clean up
931  * driver private framebuffers embedded into a larger structure.
932  *
933  * Note that this function does not remove the fb from active usage - if it is
934  * still used anywhere, hilarity can ensue since userspace could call getfb on
935  * the id and get back -EINVAL. Obviously no concern at driver unload time.
936  *
937  * Also, the framebuffer will not be removed from the lookup idr - for
938  * user-created framebuffers this will happen in the rmfb ioctl. For
939  * driver-private objects (e.g. for fbdev) drivers need to explicitly call
940  * drm_framebuffer_unregister_private.
941  */
942 void drm_framebuffer_cleanup(struct drm_framebuffer *fb)
943 {
944 	struct drm_device *dev = fb->dev;
945 
946 	mutex_lock(&dev->mode_config.fb_lock);
947 	list_del(&fb->head);
948 	dev->mode_config.num_fb--;
949 	mutex_unlock(&dev->mode_config.fb_lock);
950 }
951 EXPORT_SYMBOL(drm_framebuffer_cleanup);
952 
953 static int atomic_remove_fb(struct drm_framebuffer *fb)
954 {
955 	struct drm_modeset_acquire_ctx ctx;
956 	struct drm_device *dev = fb->dev;
957 	struct drm_atomic_state *state;
958 	struct drm_plane *plane;
959 	struct drm_connector *conn __maybe_unused;
960 	struct drm_connector_state *conn_state;
961 	int i, ret;
962 	unsigned plane_mask;
963 	bool disable_crtcs = false;
964 
965 retry_disable:
966 	drm_modeset_acquire_init(&ctx, 0);
967 
968 	state = drm_atomic_state_alloc(dev);
969 	if (!state) {
970 		ret = -ENOMEM;
971 		goto out;
972 	}
973 	state->acquire_ctx = &ctx;
974 
975 retry:
976 	plane_mask = 0;
977 	ret = drm_modeset_lock_all_ctx(dev, &ctx);
978 	if (ret)
979 		goto unlock;
980 
981 	drm_for_each_plane(plane, dev) {
982 		struct drm_plane_state *plane_state;
983 
984 		if (plane->state->fb != fb)
985 			continue;
986 
987 		drm_dbg_kms(dev,
988 			    "Disabling [PLANE:%d:%s] because [FB:%d] is removed\n",
989 			    plane->base.id, plane->name, fb->base.id);
990 
991 		plane_state = drm_atomic_get_plane_state(state, plane);
992 		if (IS_ERR(plane_state)) {
993 			ret = PTR_ERR(plane_state);
994 			goto unlock;
995 		}
996 
997 		if (disable_crtcs && plane_state->crtc->primary == plane) {
998 			struct drm_crtc_state *crtc_state;
999 
1000 			drm_dbg_kms(dev,
1001 				    "Disabling [CRTC:%d:%s] because [FB:%d] is removed\n",
1002 				    plane_state->crtc->base.id,
1003 				    plane_state->crtc->name, fb->base.id);
1004 
1005 			crtc_state = drm_atomic_get_existing_crtc_state(state, plane_state->crtc);
1006 
1007 			ret = drm_atomic_add_affected_connectors(state, plane_state->crtc);
1008 			if (ret)
1009 				goto unlock;
1010 
1011 			crtc_state->active = false;
1012 			ret = drm_atomic_set_mode_for_crtc(crtc_state, NULL);
1013 			if (ret)
1014 				goto unlock;
1015 		}
1016 
1017 		drm_atomic_set_fb_for_plane(plane_state, NULL);
1018 		ret = drm_atomic_set_crtc_for_plane(plane_state, NULL);
1019 		if (ret)
1020 			goto unlock;
1021 
1022 		plane_mask |= drm_plane_mask(plane);
1023 	}
1024 
1025 	/* This list is only filled when disable_crtcs is set. */
1026 	for_each_new_connector_in_state(state, conn, conn_state, i) {
1027 		ret = drm_atomic_set_crtc_for_connector(conn_state, NULL);
1028 
1029 		if (ret)
1030 			goto unlock;
1031 	}
1032 
1033 	if (plane_mask)
1034 		ret = drm_atomic_commit(state);
1035 
1036 unlock:
1037 	if (ret == -EDEADLK) {
1038 		drm_atomic_state_clear(state);
1039 		drm_modeset_backoff(&ctx);
1040 		goto retry;
1041 	}
1042 
1043 	drm_atomic_state_put(state);
1044 
1045 out:
1046 	drm_modeset_drop_locks(&ctx);
1047 	drm_modeset_acquire_fini(&ctx);
1048 
1049 	if (ret == -EINVAL && !disable_crtcs) {
1050 		disable_crtcs = true;
1051 		goto retry_disable;
1052 	}
1053 
1054 	return ret;
1055 }
1056 
1057 static void legacy_remove_fb(struct drm_framebuffer *fb)
1058 {
1059 	struct drm_device *dev = fb->dev;
1060 	struct drm_crtc *crtc;
1061 	struct drm_plane *plane;
1062 
1063 	drm_modeset_lock_all(dev);
1064 	/* remove from any CRTC */
1065 	drm_for_each_crtc(crtc, dev) {
1066 		if (crtc->primary->fb == fb) {
1067 			drm_dbg_kms(dev,
1068 				    "Disabling [CRTC:%d:%s] because [FB:%d] is removed\n",
1069 				    crtc->base.id, crtc->name, fb->base.id);
1070 
1071 			/* should turn off the crtc */
1072 			if (drm_crtc_force_disable(crtc))
1073 				DRM_ERROR("failed to reset crtc %p when fb was deleted\n", crtc);
1074 		}
1075 	}
1076 
1077 	drm_for_each_plane(plane, dev) {
1078 		if (plane->fb == fb) {
1079 			drm_dbg_kms(dev,
1080 				    "Disabling [PLANE:%d:%s] because [FB:%d] is removed\n",
1081 				    plane->base.id, plane->name, fb->base.id);
1082 			drm_plane_force_disable(plane);
1083 		}
1084 	}
1085 	drm_modeset_unlock_all(dev);
1086 }
1087 
1088 /**
1089  * drm_framebuffer_remove - remove and unreference a framebuffer object
1090  * @fb: framebuffer to remove
1091  *
1092  * Scans all the CRTCs and planes in @dev's mode_config.  If they're
1093  * using @fb, removes it, setting it to NULL. Then drops the reference to the
1094  * passed-in framebuffer. Might take the modeset locks.
1095  *
1096  * Note that this function optimizes the cleanup away if the caller holds the
1097  * last reference to the framebuffer. It is also guaranteed to not take the
1098  * modeset locks in this case.
1099  */
1100 void drm_framebuffer_remove(struct drm_framebuffer *fb)
1101 {
1102 	struct drm_device *dev;
1103 
1104 	if (!fb)
1105 		return;
1106 
1107 	dev = fb->dev;
1108 
1109 	WARN_ON(!list_empty(&fb->filp_head));
1110 
1111 	/*
1112 	 * drm ABI mandates that we remove any deleted framebuffers from active
1113 	 * usage. But since most sane clients only remove framebuffers they no
1114 	 * longer need, try to optimize this away.
1115 	 *
1116 	 * Since we're holding a reference ourselves, observing a refcount of 1
1117 	 * means that we're the last holder and can skip it. Also, the refcount
1118 	 * can never increase from 1 again, so we don't need any barriers or
1119 	 * locks.
1120 	 *
1121 	 * Note that userspace could try to race with use and instate a new
1122 	 * usage _after_ we've cleared all current ones. End result will be an
1123 	 * in-use fb with fb-id == 0. Userspace is allowed to shoot its own foot
1124 	 * in this manner.
1125 	 */
1126 	if (drm_framebuffer_read_refcount(fb) > 1) {
1127 		if (drm_drv_uses_atomic_modeset(dev)) {
1128 			int ret = atomic_remove_fb(fb);
1129 
1130 			WARN(ret, "atomic remove_fb failed with %i\n", ret);
1131 		} else
1132 			legacy_remove_fb(fb);
1133 	}
1134 
1135 	drm_framebuffer_put(fb);
1136 }
1137 EXPORT_SYMBOL(drm_framebuffer_remove);
1138 
1139 /**
1140  * drm_framebuffer_plane_width - width of the plane given the first plane
1141  * @width: width of the first plane
1142  * @fb: the framebuffer
1143  * @plane: plane index
1144  *
1145  * Returns:
1146  * The width of @plane, given that the width of the first plane is @width.
1147  */
1148 int drm_framebuffer_plane_width(int width,
1149 				const struct drm_framebuffer *fb, int plane)
1150 {
1151 	if (plane >= fb->format->num_planes)
1152 		return 0;
1153 
1154 	return fb_plane_width(width, fb->format, plane);
1155 }
1156 EXPORT_SYMBOL(drm_framebuffer_plane_width);
1157 
1158 /**
1159  * drm_framebuffer_plane_height - height of the plane given the first plane
1160  * @height: height of the first plane
1161  * @fb: the framebuffer
1162  * @plane: plane index
1163  *
1164  * Returns:
1165  * The height of @plane, given that the height of the first plane is @height.
1166  */
1167 int drm_framebuffer_plane_height(int height,
1168 				 const struct drm_framebuffer *fb, int plane)
1169 {
1170 	if (plane >= fb->format->num_planes)
1171 		return 0;
1172 
1173 	return fb_plane_height(height, fb->format, plane);
1174 }
1175 EXPORT_SYMBOL(drm_framebuffer_plane_height);
1176 
1177 void drm_framebuffer_print_info(struct drm_printer *p, unsigned int indent,
1178 				const struct drm_framebuffer *fb)
1179 {
1180 	unsigned int i;
1181 
1182 	drm_printf_indent(p, indent, "allocated by = %s\n", fb->comm);
1183 	drm_printf_indent(p, indent, "refcount=%u\n",
1184 			  drm_framebuffer_read_refcount(fb));
1185 	drm_printf_indent(p, indent, "format=%p4cc\n", &fb->format->format);
1186 	drm_printf_indent(p, indent, "modifier=0x%llx\n", fb->modifier);
1187 	drm_printf_indent(p, indent, "size=%ux%u\n", fb->width, fb->height);
1188 	drm_printf_indent(p, indent, "layers:\n");
1189 
1190 	for (i = 0; i < fb->format->num_planes; i++) {
1191 		drm_printf_indent(p, indent + 1, "size[%u]=%dx%d\n", i,
1192 				  drm_framebuffer_plane_width(fb->width, fb, i),
1193 				  drm_framebuffer_plane_height(fb->height, fb, i));
1194 		drm_printf_indent(p, indent + 1, "pitch[%u]=%u\n", i, fb->pitches[i]);
1195 		drm_printf_indent(p, indent + 1, "offset[%u]=%u\n", i, fb->offsets[i]);
1196 		drm_printf_indent(p, indent + 1, "obj[%u]:%s\n", i,
1197 				  fb->obj[i] ? "" : "(null)");
1198 		if (fb->obj[i])
1199 			drm_gem_print_info(p, indent + 2, fb->obj[i]);
1200 	}
1201 }
1202 
1203 #ifdef CONFIG_DEBUG_FS
1204 static int drm_framebuffer_info(struct seq_file *m, void *data)
1205 {
1206 	struct drm_info_node *node = m->private;
1207 	struct drm_device *dev = node->minor->dev;
1208 	struct drm_printer p = drm_seq_file_printer(m);
1209 	struct drm_framebuffer *fb;
1210 
1211 	mutex_lock(&dev->mode_config.fb_lock);
1212 	drm_for_each_fb(fb, dev) {
1213 		drm_printf(&p, "framebuffer[%u]:\n", fb->base.id);
1214 		drm_framebuffer_print_info(&p, 1, fb);
1215 	}
1216 	mutex_unlock(&dev->mode_config.fb_lock);
1217 
1218 	return 0;
1219 }
1220 
1221 static const struct drm_info_list drm_framebuffer_debugfs_list[] = {
1222 	{ "framebuffer", drm_framebuffer_info, 0 },
1223 };
1224 
1225 void drm_framebuffer_debugfs_init(struct drm_minor *minor)
1226 {
1227 	drm_debugfs_create_files(drm_framebuffer_debugfs_list,
1228 				 ARRAY_SIZE(drm_framebuffer_debugfs_list),
1229 				 minor->debugfs_root, minor);
1230 }
1231 #endif
1232