xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/drm_bufs.c (revision 407b0b05e5a0eded3b0ec654182831b735595cfb)
1 /*	$NetBSD: drm_bufs.c,v 1.16 2021/12/19 12:30:04 riastradh Exp $	*/
2 
3 /*
4  * Legacy: Generic DRM Buffer Management
5  *
6  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
7  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
8  * All Rights Reserved.
9  *
10  * Author: Rickard E. (Rik) Faith <faith@valinux.com>
11  * Author: Gareth Hughes <gareth@valinux.com>
12  *
13  * Permission is hereby granted, free of charge, to any person obtaining a
14  * copy of this software and associated documentation files (the "Software"),
15  * to deal in the Software without restriction, including without limitation
16  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
17  * and/or sell copies of the Software, and to permit persons to whom the
18  * Software is furnished to do so, subject to the following conditions:
19  *
20  * The above copyright notice and this permission notice (including the next
21  * paragraph) shall be included in all copies or substantial portions of the
22  * Software.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
25  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
26  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
27  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
28  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
29  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
30  * OTHER DEALINGS IN THE SOFTWARE.
31  */
32 
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: drm_bufs.c,v 1.16 2021/12/19 12:30:04 riastradh Exp $");
35 
36 #include <linux/export.h>
37 #include <linux/log2.h>
38 #include <linux/mm.h>
39 #include <linux/mman.h>
40 #include <linux/nospec.h>
41 #include <linux/slab.h>
42 #include <linux/uaccess.h>
43 #include <linux/vmalloc.h>
44 
45 #include <asm/shmparam.h>
46 
47 #include <drm/drm_agpsupport.h>
48 #include <drm/drm_device.h>
49 #include <drm/drm_drv.h>
50 #include <drm/drm_file.h>
51 #include <drm/drm_pci.h>
52 #include <drm/drm_print.h>
53 
54 #include "drm_legacy.h"
55 
56 
drm_find_matching_map(struct drm_device * dev,struct drm_local_map * map)57 static struct drm_map_list *drm_find_matching_map(struct drm_device *dev,
58 						  struct drm_local_map *map)
59 {
60 	struct drm_map_list *entry;
61 	list_for_each_entry(entry, &dev->maplist, head) {
62 		/*
63 		 * Because the kernel-userspace ABI is fixed at a 32-bit offset
64 		 * while PCI resources may live above that, we only compare the
65 		 * lower 32 bits of the map offset for maps of type
66 		 * _DRM_FRAMEBUFFER or _DRM_REGISTERS.
67 		 * It is assumed that if a driver have more than one resource
68 		 * of each type, the lower 32 bits are different.
69 		 */
70 		if (!entry->map ||
71 		    map->type != entry->map->type ||
72 		    entry->master != dev->master)
73 			continue;
74 		switch (map->type) {
75 		case _DRM_SHM:
76 			if (map->flags != _DRM_CONTAINS_LOCK)
77 				break;
78 			return entry;
79 		case _DRM_REGISTERS:
80 		case _DRM_FRAME_BUFFER:
81 			if ((entry->map->offset & 0xffffffff) ==
82 			    (map->offset & 0xffffffff))
83 				return entry;
84 		default: /* Make gcc happy */
85 			;
86 		}
87 		if (entry->map->offset == map->offset)
88 			return entry;
89 	}
90 
91 	return NULL;
92 }
93 
drm_map_handle(struct drm_device * dev,struct drm_hash_item * hash,unsigned long user_token,int hashed_handle,int shm)94 static int drm_map_handle(struct drm_device *dev, struct drm_hash_item *hash,
95 			  unsigned long user_token, int hashed_handle, int shm)
96 {
97 	int use_hashed_handle, shift;
98 	unsigned long add;
99 
100 	use_hashed_handle = (user_token &~ 0xffffffffUL) || hashed_handle;
101 	if (!use_hashed_handle) {
102 		int ret;
103 		hash->key = user_token >> PAGE_SHIFT;
104 		ret = drm_ht_insert_item(&dev->map_hash, hash);
105 		if (ret != -EINVAL)
106 			return ret;
107 	}
108 
109 	shift = 0;
110 	add = DRM_MAP_HASH_OFFSET >> PAGE_SHIFT;
111 	if (shm && (SHMLBA > PAGE_SIZE)) {
112 		int bits = ilog2(SHMLBA >> PAGE_SHIFT) + 1;
113 
114 		/* For shared memory, we have to preserve the SHMLBA
115 		 * bits of the eventual vma->vm_pgoff value during
116 		 * mmap().  Otherwise we run into cache aliasing problems
117 		 * on some platforms.  On these platforms, the pgoff of
118 		 * a mmap() request is used to pick a suitable virtual
119 		 * address for the mmap() region such that it will not
120 		 * cause cache aliasing problems.
121 		 *
122 		 * Therefore, make sure the SHMLBA relevant bits of the
123 		 * hash value we use are equal to those in the original
124 		 * kernel virtual address.
125 		 */
126 		shift = bits;
127 		add |= ((user_token >> PAGE_SHIFT) & ((1UL << bits) - 1UL));
128 	}
129 
130 	return drm_ht_just_insert_please(&dev->map_hash, hash,
131 					 user_token, 32 - PAGE_SHIFT - 3,
132 					 shift, add);
133 }
134 
135 /**
136  * Core function to create a range of memory available for mapping by a
137  * non-root process.
138  *
139  * Adjusts the memory offset to its absolute value according to the mapping
140  * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
141  * applicable and if supported by the kernel.
142  */
drm_addmap_core(struct drm_device * dev,resource_size_t offset,unsigned int size,enum drm_map_type type,enum drm_map_flags flags,struct drm_map_list ** maplist)143 static int drm_addmap_core(struct drm_device *dev, resource_size_t offset,
144 			   unsigned int size, enum drm_map_type type,
145 			   enum drm_map_flags flags,
146 			   struct drm_map_list **maplist)
147 {
148 	struct drm_local_map *map;
149 	struct drm_map_list *list;
150 	drm_dma_handle_t *dmah;
151 	unsigned long user_token;
152 	int ret;
153 
154 	map = kmalloc(sizeof(*map), GFP_KERNEL);
155 	if (!map)
156 		return -ENOMEM;
157 
158 	map->offset = offset;
159 	map->size = size;
160 	map->flags = flags;
161 	map->type = type;
162 
163 	/* Only allow shared memory to be removable since we only keep enough
164 	 * book keeping information about shared memory to allow for removal
165 	 * when processes fork.
166 	 */
167 	if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
168 		kfree(map);
169 		return -EINVAL;
170 	}
171 	DRM_DEBUG("offset = 0x%08llx, size = 0x%08lx, type = %d\n",
172 		  (unsigned long long)map->offset, map->size, map->type);
173 
174 	/* page-align _DRM_SHM maps. They are allocated here so there is no security
175 	 * hole created by that and it works around various broken drivers that use
176 	 * a non-aligned quantity to map the SAREA. --BenH
177 	 */
178 	if (map->type == _DRM_SHM)
179 		map->size = PAGE_ALIGN(map->size);
180 
181 	if ((map->offset & (~(resource_size_t)PAGE_MASK)) || (map->size & (~PAGE_MASK))) {
182 		kfree(map);
183 		return -EINVAL;
184 	}
185 	map->mtrr = -1;
186 	map->handle = NULL;
187 
188 	switch (map->type) {
189 	case _DRM_REGISTERS:
190 	case _DRM_FRAME_BUFFER:
191 #ifndef __NetBSD__		/* XXX No idea what this is for...  */
192 #if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__) && !defined(__arm__)
193 		if (map->offset + (map->size-1) < map->offset ||
194 		    map->offset < virt_to_phys(high_memory)) {
195 			kfree(map);
196 			return -EINVAL;
197 		}
198 #endif
199 #endif
200 		/* Some drivers preinitialize some maps, without the X Server
201 		 * needing to be aware of it.  Therefore, we just return success
202 		 * when the server tries to create a duplicate map.
203 		 */
204 		list = drm_find_matching_map(dev, map);
205 		if (list != NULL) {
206 			if (list->map->size != map->size) {
207 				DRM_DEBUG("Matching maps of type %d with "
208 					  "mismatched sizes, (%ld vs %ld)\n",
209 					  map->type, map->size,
210 					  list->map->size);
211 				list->map->size = map->size;
212 			}
213 
214 			kfree(map);
215 			*maplist = list;
216 			return 0;
217 		}
218 
219 		if (map->type == _DRM_FRAME_BUFFER ||
220 		    (map->flags & _DRM_WRITE_COMBINING)) {
221 			map->mtrr =
222 				arch_phys_wc_add(map->offset, map->size);
223 		}
224 		if (map->type == _DRM_REGISTERS) {
225 #ifdef __NetBSD__
226 			drm_legacy_ioremap(map, dev);
227 #else
228 			if (map->flags & _DRM_WRITE_COMBINING)
229 				map->handle = ioremap_wc(map->offset,
230 							 map->size);
231 			else
232 				map->handle = ioremap(map->offset, map->size);
233 #endif
234 			if (!map->handle) {
235 				kfree(map);
236 				return -ENOMEM;
237 			}
238 		}
239 
240 		break;
241 	case _DRM_SHM:
242 		list = drm_find_matching_map(dev, map);
243 		if (list != NULL) {
244 			if (list->map->size != map->size) {
245 				DRM_DEBUG("Matching maps of type %d with "
246 					  "mismatched sizes, (%ld vs %ld)\n",
247 					  map->type, map->size, list->map->size);
248 				list->map->size = map->size;
249 			}
250 
251 			kfree(map);
252 			*maplist = list;
253 			return 0;
254 		}
255 		map->handle = vmalloc_user(map->size);
256 		DRM_DEBUG("%lu %d %p\n",
257 			  map->size, order_base_2(map->size), map->handle);
258 		if (!map->handle) {
259 			kfree(map);
260 			return -ENOMEM;
261 		}
262 		map->offset = (unsigned long)map->handle;
263 		if (map->flags & _DRM_CONTAINS_LOCK) {
264 			/* Prevent a 2nd X Server from creating a 2nd lock */
265 			spin_lock(&dev->master->lock.spinlock);
266 			if (dev->master->lock.hw_lock != NULL) {
267 				spin_unlock(&dev->master->lock.spinlock);
268 				vfree(map->handle);
269 				kfree(map);
270 				return -EBUSY;
271 			}
272 			spin_unlock(&dev->master->lock.spinlock);
273 			dev->sigdata.lock = dev->master->lock.hw_lock = map->handle;	/* Pointer to lock */
274 		}
275 		break;
276 	case _DRM_AGP: {
277 		struct drm_agp_mem *entry;
278 		int valid = 0;
279 
280 		if (!dev->agp) {
281 			kfree(map);
282 			return -EINVAL;
283 		}
284 #ifdef __alpha__
285 		map->offset += dev->hose->mem_space->start;
286 #endif
287 		/* In some cases (i810 driver), user space may have already
288 		 * added the AGP base itself, because dev->agp->base previously
289 		 * only got set during AGP enable.  So, only add the base
290 		 * address if the map's offset isn't already within the
291 		 * aperture.
292 		 */
293 #ifdef __NetBSD__
294 		if (map->offset < dev->agp->base ||
295 		    map->offset > dev->agp->base +
296 		    dev->agp->agp_info.aki_info.ai_aperture_size - 1) {
297 			map->offset += dev->agp->base;
298 		}
299 #else
300 		if (map->offset < dev->agp->base ||
301 		    map->offset > dev->agp->base +
302 		    dev->agp->agp_info.aper_size * 1024 * 1024 - 1) {
303 			map->offset += dev->agp->base;
304 		}
305 #endif
306 		map->mtrr = dev->agp->agp_mtrr;	/* for getmap */
307 
308 		/* This assumes the DRM is in total control of AGP space.
309 		 * It's not always the case as AGP can be in the control
310 		 * of user space (i.e. i810 driver). So this loop will get
311 		 * skipped and we double check that dev->agp->memory is
312 		 * actually set as well as being invalid before EPERM'ing
313 		 */
314 		list_for_each_entry(entry, &dev->agp->memory, head) {
315 			if ((map->offset >= entry->bound) &&
316 			    (map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
317 				valid = 1;
318 				break;
319 			}
320 		}
321 		if (!list_empty(&dev->agp->memory) && !valid) {
322 			kfree(map);
323 			return -EPERM;
324 		}
325 		DRM_DEBUG("AGP offset = 0x%08llx, size = 0x%08lx\n",
326 			  (unsigned long long)map->offset, map->size);
327 
328 		break;
329 	}
330 	case _DRM_SCATTER_GATHER:
331 		if (!dev->sg) {
332 			kfree(map);
333 			return -EINVAL;
334 		}
335 		map->offset += (unsigned long)dev->sg->virtual;
336 		break;
337 	case _DRM_CONSISTENT:
338 		/* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
339 		 * As we're limiting the address to 2^32-1 (or less),
340 		 * casting it down to 32 bits is no problem, but we
341 		 * need to point to a 64bit variable first. */
342 		dmah = drm_pci_alloc(dev, map->size, map->size);
343 		if (!dmah) {
344 			kfree(map);
345 			return -ENOMEM;
346 		}
347 		map->handle = dmah->vaddr;
348 		map->offset = (unsigned long)dmah->busaddr;
349 #ifdef __NetBSD__
350 		map->lm_data.dmah = dmah;
351 #else
352 		kfree(dmah);
353 #endif
354 		break;
355 	default:
356 		kfree(map);
357 		return -EINVAL;
358 	}
359 
360 	list = kzalloc(sizeof(*list), GFP_KERNEL);
361 	if (!list) {
362 		if (map->type == _DRM_REGISTERS)
363 #ifdef __NetBSD__
364 			drm_legacy_ioremapfree(map, dev);
365 #else
366 			iounmap(map->handle);
367 #endif
368 		kfree(map);
369 		return -EINVAL;
370 	}
371 	list->map = map;
372 
373 	mutex_lock(&dev->struct_mutex);
374 	list_add(&list->head, &dev->maplist);
375 
376 	/* Assign a 32-bit handle */
377 	/* We do it here so that dev->struct_mutex protects the increment */
378 	user_token = (map->type == _DRM_SHM) ? (unsigned long)map->handle :
379 		map->offset;
380 	ret = drm_map_handle(dev, &list->hash, user_token, 0,
381 			     (map->type == _DRM_SHM));
382 	if (ret) {
383 		if (map->type == _DRM_REGISTERS)
384 #ifdef __NetBSD__		/* XXX What about other map types...?  */
385 			drm_legacy_ioremapfree(map, dev);
386 #else
387 			iounmap(map->handle);
388 #endif
389 		kfree(map);
390 		kfree(list);
391 		mutex_unlock(&dev->struct_mutex);
392 		return ret;
393 	}
394 
395 	list->user_token = list->hash.key << PAGE_SHIFT;
396 	mutex_unlock(&dev->struct_mutex);
397 
398 	if (!(map->flags & _DRM_DRIVER))
399 		list->master = dev->master;
400 	*maplist = list;
401 	return 0;
402 }
403 
drm_legacy_addmap(struct drm_device * dev,resource_size_t offset,unsigned int size,enum drm_map_type type,enum drm_map_flags flags,struct drm_local_map ** map_ptr)404 int drm_legacy_addmap(struct drm_device *dev, resource_size_t offset,
405 		      unsigned int size, enum drm_map_type type,
406 		      enum drm_map_flags flags, struct drm_local_map **map_ptr)
407 {
408 	struct drm_map_list *list;
409 	int rc;
410 
411 	rc = drm_addmap_core(dev, offset, size, type, flags, &list);
412 	if (!rc)
413 		*map_ptr = list->map;
414 	return rc;
415 }
416 EXPORT_SYMBOL(drm_legacy_addmap);
417 
drm_legacy_findmap(struct drm_device * dev,unsigned int token)418 struct drm_local_map *drm_legacy_findmap(struct drm_device *dev,
419 					 unsigned int token)
420 {
421 	struct drm_map_list *_entry;
422 	list_for_each_entry(_entry, &dev->maplist, head)
423 		if (_entry->user_token == token)
424 			return _entry->map;
425 	return NULL;
426 }
427 EXPORT_SYMBOL(drm_legacy_findmap);
428 
429 /**
430  * Ioctl to specify a range of memory that is available for mapping by a
431  * non-root process.
432  *
433  * \param inode device inode.
434  * \param file_priv DRM file private.
435  * \param cmd command.
436  * \param arg pointer to a drm_map structure.
437  * \return zero on success or a negative value on error.
438  *
439  */
drm_legacy_addmap_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)440 int drm_legacy_addmap_ioctl(struct drm_device *dev, void *data,
441 			    struct drm_file *file_priv)
442 {
443 	struct drm_map *map = data;
444 	struct drm_map_list *maplist;
445 	int err;
446 
447 	if (!(capable(CAP_SYS_ADMIN) || map->type == _DRM_AGP || map->type == _DRM_SHM))
448 		return -EPERM;
449 
450 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
451 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
452 		return -EOPNOTSUPP;
453 
454 	err = drm_addmap_core(dev, map->offset, map->size, map->type,
455 			      map->flags, &maplist);
456 
457 	if (err)
458 		return err;
459 
460 	/* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
461 	map->handle = (void *)(unsigned long)maplist->user_token;
462 
463 	/*
464 	 * It appears that there are no users of this value whatsoever --
465 	 * drmAddMap just discards it.  Let's not encourage its use.
466 	 * (Keeping drm_addmap_core's returned mtrr value would be wrong --
467 	 *  it's not a real mtrr index anymore.)
468 	 */
469 	map->mtrr = -1;
470 
471 	return 0;
472 }
473 
474 /*
475  * Get a mapping information.
476  *
477  * \param inode device inode.
478  * \param file_priv DRM file private.
479  * \param cmd command.
480  * \param arg user argument, pointing to a drm_map structure.
481  *
482  * \return zero on success or a negative number on failure.
483  *
484  * Searches for the mapping with the specified offset and copies its information
485  * into userspace
486  */
drm_legacy_getmap_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)487 int drm_legacy_getmap_ioctl(struct drm_device *dev, void *data,
488 			    struct drm_file *file_priv)
489 {
490 	struct drm_map *map = data;
491 	struct drm_map_list *r_list = NULL;
492 	struct list_head *list;
493 	int idx;
494 	int i;
495 
496 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
497 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
498 		return -EOPNOTSUPP;
499 
500 	idx = map->offset;
501 	if (idx < 0)
502 		return -EINVAL;
503 
504 	i = 0;
505 	mutex_lock(&dev->struct_mutex);
506 	list_for_each(list, &dev->maplist) {
507 		if (i == idx) {
508 			r_list = list_entry(list, struct drm_map_list, head);
509 			break;
510 		}
511 		i++;
512 	}
513 	if (!r_list || !r_list->map) {
514 		mutex_unlock(&dev->struct_mutex);
515 		return -EINVAL;
516 	}
517 
518 	map->offset = r_list->map->offset;
519 	map->size = r_list->map->size;
520 	map->type = r_list->map->type;
521 	map->flags = r_list->map->flags;
522 	map->handle = (void *)(unsigned long) r_list->user_token;
523 	map->mtrr = arch_phys_wc_index(r_list->map->mtrr);
524 
525 	mutex_unlock(&dev->struct_mutex);
526 
527 	return 0;
528 }
529 
530 /**
531  * Remove a map private from list and deallocate resources if the mapping
532  * isn't in use.
533  *
534  * Searches the map on drm_device::maplist, removes it from the list, see if
535  * it's being used, and free any associated resource (such as MTRR's) if it's not
536  * being on use.
537  *
538  * \sa drm_legacy_addmap
539  */
drm_legacy_rmmap_locked(struct drm_device * dev,struct drm_local_map * map)540 int drm_legacy_rmmap_locked(struct drm_device *dev, struct drm_local_map *map)
541 {
542 	struct drm_map_list *r_list = NULL, *list_t;
543 #ifndef __NetBSD__
544 	drm_dma_handle_t dmah;
545 #endif
546 	int found = 0;
547 	struct drm_master *master;
548 
549 	/* Find the list entry for the map and remove it */
550 	list_for_each_entry_safe(r_list, list_t, &dev->maplist, head) {
551 		if (r_list->map == map) {
552 			master = r_list->master;
553 			list_del(&r_list->head);
554 			drm_ht_remove_key(&dev->map_hash,
555 					  r_list->user_token >> PAGE_SHIFT);
556 			kfree(r_list);
557 			found = 1;
558 			break;
559 		}
560 	}
561 
562 	if (!found)
563 		return -EINVAL;
564 
565 	switch (map->type) {
566 	case _DRM_REGISTERS:
567 #ifdef __NetBSD__
568 		drm_legacy_ioremapfree(map, dev);
569 #else
570 		iounmap(map->handle);
571 #endif
572 		/* FALLTHROUGH */
573 	case _DRM_FRAME_BUFFER:
574 		arch_phys_wc_del(map->mtrr);
575 		break;
576 	case _DRM_SHM:
577 		if (master && (map->flags & _DRM_CONTAINS_LOCK)) {
578 			spin_lock(&master->lock.spinlock);
579 			/*
580 			 * If we successfully removed this mapping,
581 			 * then the mapping must have been there in the
582 			 * first place, and we must have had a
583 			 * heavyweight lock, so we assert here instead
584 			 * of just checking and failing.
585 			 *
586 			 * XXX What about the _DRM_CONTAINS_LOCK flag?
587 			 * Where is that supposed to be set?  Is it
588 			 * equivalent to having a master set?
589 			 *
590 			 * XXX There is copypasta of this in
591 			 * drm_lock.c, drm_legacy_lock_master_cleanup.
592 			 */
593 			BUG_ON(master->lock.hw_lock == NULL);
594 			if (dev->sigdata.lock == master->lock.hw_lock)
595 				dev->sigdata.lock = NULL;
596 			master->lock.hw_lock = NULL;   /* SHM removed */
597 			master->lock.file_priv = NULL;
598 #ifdef __NetBSD__
599 			DRM_SPIN_WAKEUP_ALL(&master->lock.lock_queue,
600 			    &master->lock.spinlock);
601 #else
602 			wake_up_interruptible_all(&master->lock.lock_queue);
603 #endif
604 			spin_unlock(&master->lock.spinlock);
605 		}
606 		vfree(map->handle);
607 		break;
608 	case _DRM_AGP:
609 	case _DRM_SCATTER_GATHER:
610 		break;
611 	case _DRM_CONSISTENT:
612 #ifdef __NetBSD__
613 		drm_pci_free(dev, map->lm_data.dmah);
614 #else
615 		dmah.vaddr = map->handle;
616 		dmah.busaddr = map->offset;
617 		dmah.size = map->size;
618 		__drm_legacy_pci_free(dev, &dmah);
619 #endif
620 		break;
621 	}
622 	kfree(map);
623 
624 	return 0;
625 }
626 EXPORT_SYMBOL(drm_legacy_rmmap_locked);
627 
drm_legacy_rmmap(struct drm_device * dev,struct drm_local_map * map)628 void drm_legacy_rmmap(struct drm_device *dev, struct drm_local_map *map)
629 {
630 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
631 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
632 		return;
633 
634 	mutex_lock(&dev->struct_mutex);
635 	drm_legacy_rmmap_locked(dev, map);
636 	mutex_unlock(&dev->struct_mutex);
637 }
638 EXPORT_SYMBOL(drm_legacy_rmmap);
639 
drm_legacy_master_rmmaps(struct drm_device * dev,struct drm_master * master)640 void drm_legacy_master_rmmaps(struct drm_device *dev, struct drm_master *master)
641 {
642 	struct drm_map_list *r_list, *list_temp;
643 
644 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
645 		return;
646 
647 	mutex_lock(&dev->struct_mutex);
648 	list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
649 		if (r_list->master == master) {
650 			drm_legacy_rmmap_locked(dev, r_list->map);
651 			r_list = NULL;
652 		}
653 	}
654 	mutex_unlock(&dev->struct_mutex);
655 }
656 
drm_legacy_rmmaps(struct drm_device * dev)657 void drm_legacy_rmmaps(struct drm_device *dev)
658 {
659 	struct drm_map_list *r_list, *list_temp;
660 
661 	list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head)
662 		drm_legacy_rmmap(dev, r_list->map);
663 }
664 
665 /* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
666  * the last close of the device, and this is necessary for cleanup when things
667  * exit uncleanly.  Therefore, having userland manually remove mappings seems
668  * like a pointless exercise since they're going away anyway.
669  *
670  * One use case might be after addmap is allowed for normal users for SHM and
671  * gets used by drivers that the server doesn't need to care about.  This seems
672  * unlikely.
673  *
674  * \param inode device inode.
675  * \param file_priv DRM file private.
676  * \param cmd command.
677  * \param arg pointer to a struct drm_map structure.
678  * \return zero on success or a negative value on error.
679  */
drm_legacy_rmmap_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)680 int drm_legacy_rmmap_ioctl(struct drm_device *dev, void *data,
681 			   struct drm_file *file_priv)
682 {
683 	struct drm_map *request = data;
684 	struct drm_local_map *map = NULL;
685 	struct drm_map_list *r_list;
686 	int ret;
687 
688 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
689 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
690 		return -EOPNOTSUPP;
691 
692 	mutex_lock(&dev->struct_mutex);
693 	list_for_each_entry(r_list, &dev->maplist, head) {
694 		if (r_list->map &&
695 		    r_list->user_token == (unsigned long)request->handle &&
696 		    r_list->map->flags & _DRM_REMOVABLE) {
697 			map = r_list->map;
698 			break;
699 		}
700 	}
701 
702 	/* List has wrapped around to the head pointer, or it's empty we didn't
703 	 * find anything.
704 	 */
705 	if (list_empty(&dev->maplist) || !map) {
706 		mutex_unlock(&dev->struct_mutex);
707 		return -EINVAL;
708 	}
709 
710 	/* Register and framebuffer maps are permanent */
711 	if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
712 		mutex_unlock(&dev->struct_mutex);
713 		return 0;
714 	}
715 
716 	ret = drm_legacy_rmmap_locked(dev, map);
717 
718 	mutex_unlock(&dev->struct_mutex);
719 
720 	return ret;
721 }
722 
723 /**
724  * Cleanup after an error on one of the addbufs() functions.
725  *
726  * \param dev DRM device.
727  * \param entry buffer entry where the error occurred.
728  *
729  * Frees any pages and buffers associated with the given entry.
730  */
drm_cleanup_buf_error(struct drm_device * dev,struct drm_buf_entry * entry)731 static void drm_cleanup_buf_error(struct drm_device *dev,
732 				  struct drm_buf_entry *entry)
733 {
734 	int i;
735 
736 	if (entry->seg_count) {
737 		for (i = 0; i < entry->seg_count; i++) {
738 			if (entry->seglist[i]) {
739 				drm_pci_free(dev, entry->seglist[i]);
740 			}
741 		}
742 		kfree(entry->seglist);
743 
744 		entry->seg_count = 0;
745 	}
746 
747 	if (entry->buf_count) {
748 		for (i = 0; i < entry->buf_count; i++) {
749 			kfree(entry->buflist[i].dev_private);
750 		}
751 		kfree(entry->buflist);
752 
753 		entry->buf_count = 0;
754 	}
755 }
756 
757 #if IS_ENABLED(CONFIG_AGP)
758 /**
759  * Add AGP buffers for DMA transfers.
760  *
761  * \param dev struct drm_device to which the buffers are to be added.
762  * \param request pointer to a struct drm_buf_desc describing the request.
763  * \return zero on success or a negative number on failure.
764  *
765  * After some sanity checks creates a drm_buf structure for each buffer and
766  * reallocates the buffer list of the same size order to accommodate the new
767  * buffers.
768  */
drm_legacy_addbufs_agp(struct drm_device * dev,struct drm_buf_desc * request)769 int drm_legacy_addbufs_agp(struct drm_device *dev,
770 			   struct drm_buf_desc *request)
771 {
772 	struct drm_device_dma *dma = dev->dma;
773 	struct drm_buf_entry *entry;
774 	struct drm_agp_mem *agp_entry;
775 	struct drm_buf *buf;
776 	unsigned long offset;
777 	unsigned long agp_offset;
778 	int count;
779 	int order;
780 	int size;
781 	int alignment;
782 	int page_order;
783 	int total;
784 	int byte_count;
785 	int i, valid;
786 	struct drm_buf **temp_buflist;
787 
788 	if (!dma)
789 		return -EINVAL;
790 
791 	count = request->count;
792 	order = order_base_2(request->size);
793 	size = 1 << order;
794 
795 	alignment = (request->flags & _DRM_PAGE_ALIGN)
796 	    ? PAGE_ALIGN(size) : size;
797 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
798 	total = PAGE_SIZE << page_order;
799 
800 	byte_count = 0;
801 	agp_offset = dev->agp->base + request->agp_start;
802 
803 	DRM_DEBUG("count:      %d\n", count);
804 	DRM_DEBUG("order:      %d\n", order);
805 	DRM_DEBUG("size:       %d\n", size);
806 	DRM_DEBUG("agp_offset: %lx\n", agp_offset);
807 	DRM_DEBUG("alignment:  %d\n", alignment);
808 	DRM_DEBUG("page_order: %d\n", page_order);
809 	DRM_DEBUG("total:      %d\n", total);
810 
811 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
812 		return -EINVAL;
813 
814 	/* Make sure buffers are located in AGP memory that we own */
815 	valid = 0;
816 	list_for_each_entry(agp_entry, &dev->agp->memory, head) {
817 		if ((agp_offset >= agp_entry->bound) &&
818 		    (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
819 			valid = 1;
820 			break;
821 		}
822 	}
823 	if (!list_empty(&dev->agp->memory) && !valid) {
824 		DRM_DEBUG("zone invalid\n");
825 		return -EINVAL;
826 	}
827 	spin_lock(&dev->buf_lock);
828 	if (dev->buf_use) {
829 		spin_unlock(&dev->buf_lock);
830 		return -EBUSY;
831 	}
832 	atomic_inc(&dev->buf_alloc);
833 	spin_unlock(&dev->buf_lock);
834 
835 	mutex_lock(&dev->struct_mutex);
836 	entry = &dma->bufs[order];
837 	if (entry->buf_count) {
838 		mutex_unlock(&dev->struct_mutex);
839 		atomic_dec(&dev->buf_alloc);
840 		return -ENOMEM;	/* May only call once for each order */
841 	}
842 
843 	if (count < 0 || count > 4096) {
844 		mutex_unlock(&dev->struct_mutex);
845 		atomic_dec(&dev->buf_alloc);
846 		return -EINVAL;
847 	}
848 
849 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
850 	if (!entry->buflist) {
851 		mutex_unlock(&dev->struct_mutex);
852 		atomic_dec(&dev->buf_alloc);
853 		return -ENOMEM;
854 	}
855 
856 	entry->buf_size = size;
857 	entry->page_order = page_order;
858 
859 	offset = 0;
860 
861 	while (entry->buf_count < count) {
862 		buf = &entry->buflist[entry->buf_count];
863 		buf->idx = dma->buf_count + entry->buf_count;
864 		buf->total = alignment;
865 		buf->order = order;
866 		buf->used = 0;
867 
868 		buf->offset = (dma->byte_count + offset);
869 		buf->bus_address = agp_offset + offset;
870 		buf->address = (void *)(agp_offset + offset);
871 		buf->next = NULL;
872 		buf->waiting = 0;
873 		buf->pending = 0;
874 		buf->file_priv = NULL;
875 
876 		buf->dev_priv_size = dev->driver->dev_priv_size;
877 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
878 		if (!buf->dev_private) {
879 			/* Set count correctly so we free the proper amount. */
880 			entry->buf_count = count;
881 			drm_cleanup_buf_error(dev, entry);
882 			mutex_unlock(&dev->struct_mutex);
883 			atomic_dec(&dev->buf_alloc);
884 			return -ENOMEM;
885 		}
886 
887 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
888 
889 		offset += alignment;
890 		entry->buf_count++;
891 		byte_count += PAGE_SIZE << page_order;
892 	}
893 
894 	DRM_DEBUG("byte_count: %d\n", byte_count);
895 
896 	temp_buflist = krealloc(dma->buflist,
897 				(dma->buf_count + entry->buf_count) *
898 				sizeof(*dma->buflist), GFP_KERNEL);
899 	if (!temp_buflist) {
900 		/* Free the entry because it isn't valid */
901 		drm_cleanup_buf_error(dev, entry);
902 		mutex_unlock(&dev->struct_mutex);
903 		atomic_dec(&dev->buf_alloc);
904 		return -ENOMEM;
905 	}
906 	dma->buflist = temp_buflist;
907 
908 	for (i = 0; i < entry->buf_count; i++) {
909 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
910 	}
911 
912 	dma->buf_count += entry->buf_count;
913 	dma->seg_count += entry->seg_count;
914 	dma->page_count += byte_count >> PAGE_SHIFT;
915 	dma->byte_count += byte_count;
916 
917 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
918 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
919 
920 	mutex_unlock(&dev->struct_mutex);
921 
922 	request->count = entry->buf_count;
923 	request->size = size;
924 
925 	dma->flags = _DRM_DMA_USE_AGP;
926 
927 	atomic_dec(&dev->buf_alloc);
928 	return 0;
929 }
930 EXPORT_SYMBOL(drm_legacy_addbufs_agp);
931 #endif /* CONFIG_AGP */
932 
drm_legacy_addbufs_pci(struct drm_device * dev,struct drm_buf_desc * request)933 int drm_legacy_addbufs_pci(struct drm_device *dev,
934 			   struct drm_buf_desc *request)
935 {
936 	struct drm_device_dma *dma = dev->dma;
937 	int count;
938 	int order;
939 	int size;
940 	int total;
941 	int page_order;
942 	struct drm_buf_entry *entry;
943 	drm_dma_handle_t *dmah;
944 	struct drm_buf *buf;
945 	int alignment;
946 	unsigned long offset;
947 	int i;
948 	int byte_count;
949 	int page_count;
950 	unsigned long *temp_pagelist;
951 	struct drm_buf **temp_buflist;
952 
953 	if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
954 		return -EOPNOTSUPP;
955 
956 	if (!dma)
957 		return -EINVAL;
958 
959 	if (!capable(CAP_SYS_ADMIN))
960 		return -EPERM;
961 
962 	count = request->count;
963 	order = order_base_2(request->size);
964 	size = 1 << order;
965 
966 	DRM_DEBUG("count=%d, size=%d (%d), order=%d\n",
967 		  request->count, request->size, size, order);
968 
969 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
970 		return -EINVAL;
971 
972 	alignment = (request->flags & _DRM_PAGE_ALIGN)
973 	    ? PAGE_ALIGN(size) : size;
974 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
975 	total = PAGE_SIZE << page_order;
976 
977 	spin_lock(&dev->buf_lock);
978 	if (dev->buf_use) {
979 		spin_unlock(&dev->buf_lock);
980 		return -EBUSY;
981 	}
982 	atomic_inc(&dev->buf_alloc);
983 	spin_unlock(&dev->buf_lock);
984 
985 	mutex_lock(&dev->struct_mutex);
986 	entry = &dma->bufs[order];
987 	if (entry->buf_count) {
988 		mutex_unlock(&dev->struct_mutex);
989 		atomic_dec(&dev->buf_alloc);
990 		return -ENOMEM;	/* May only call once for each order */
991 	}
992 
993 	if (count < 0 || count > 4096) {
994 		mutex_unlock(&dev->struct_mutex);
995 		atomic_dec(&dev->buf_alloc);
996 		return -EINVAL;
997 	}
998 
999 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
1000 	if (!entry->buflist) {
1001 		mutex_unlock(&dev->struct_mutex);
1002 		atomic_dec(&dev->buf_alloc);
1003 		return -ENOMEM;
1004 	}
1005 
1006 	entry->seglist = kcalloc(count, sizeof(*entry->seglist), GFP_KERNEL);
1007 	if (!entry->seglist) {
1008 		kfree(entry->buflist);
1009 		mutex_unlock(&dev->struct_mutex);
1010 		atomic_dec(&dev->buf_alloc);
1011 		return -ENOMEM;
1012 	}
1013 
1014 	/* Keep the original pagelist until we know all the allocations
1015 	 * have succeeded
1016 	 */
1017 	temp_pagelist = kmalloc_array(dma->page_count + (count << page_order),
1018 				      sizeof(*dma->pagelist),
1019 				      GFP_KERNEL);
1020 	if (!temp_pagelist) {
1021 		kfree(entry->buflist);
1022 		kfree(entry->seglist);
1023 		mutex_unlock(&dev->struct_mutex);
1024 		atomic_dec(&dev->buf_alloc);
1025 		return -ENOMEM;
1026 	}
1027 	memcpy(temp_pagelist,
1028 	       dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
1029 	DRM_DEBUG("pagelist: %d entries\n",
1030 		  dma->page_count + (count << page_order));
1031 
1032 	entry->buf_size = size;
1033 	entry->page_order = page_order;
1034 	byte_count = 0;
1035 	page_count = 0;
1036 
1037 	while (entry->buf_count < count) {
1038 
1039 		dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
1040 
1041 		if (!dmah) {
1042 			/* Set count correctly so we free the proper amount. */
1043 			entry->buf_count = count;
1044 			entry->seg_count = count;
1045 			drm_cleanup_buf_error(dev, entry);
1046 			kfree(temp_pagelist);
1047 			mutex_unlock(&dev->struct_mutex);
1048 			atomic_dec(&dev->buf_alloc);
1049 			return -ENOMEM;
1050 		}
1051 		entry->seglist[entry->seg_count++] = dmah;
1052 		for (i = 0; i < (1 << page_order); i++) {
1053 			DRM_DEBUG("page %d @ 0x%08lx\n",
1054 				  dma->page_count + page_count,
1055 				  (unsigned long)dmah->vaddr + PAGE_SIZE * i);
1056 			temp_pagelist[dma->page_count + page_count++]
1057 				= (unsigned long)dmah->vaddr + PAGE_SIZE * i;
1058 		}
1059 		for (offset = 0;
1060 		     offset + size <= total && entry->buf_count < count;
1061 		     offset += alignment, ++entry->buf_count) {
1062 			buf = &entry->buflist[entry->buf_count];
1063 			buf->idx = dma->buf_count + entry->buf_count;
1064 			buf->total = alignment;
1065 			buf->order = order;
1066 			buf->used = 0;
1067 			buf->offset = (dma->byte_count + byte_count + offset);
1068 			buf->address = (void *)(dmah->vaddr + offset);
1069 			buf->bus_address = dmah->busaddr + offset;
1070 			buf->next = NULL;
1071 			buf->waiting = 0;
1072 			buf->pending = 0;
1073 			buf->file_priv = NULL;
1074 
1075 			buf->dev_priv_size = dev->driver->dev_priv_size;
1076 			buf->dev_private = kzalloc(buf->dev_priv_size,
1077 						GFP_KERNEL);
1078 			if (!buf->dev_private) {
1079 				/* Set count correctly so we free the proper amount. */
1080 				entry->buf_count = count;
1081 				entry->seg_count = count;
1082 				drm_cleanup_buf_error(dev, entry);
1083 				kfree(temp_pagelist);
1084 				mutex_unlock(&dev->struct_mutex);
1085 				atomic_dec(&dev->buf_alloc);
1086 				return -ENOMEM;
1087 			}
1088 
1089 			DRM_DEBUG("buffer %d @ %p\n",
1090 				  entry->buf_count, buf->address);
1091 		}
1092 		byte_count += PAGE_SIZE << page_order;
1093 	}
1094 
1095 	temp_buflist = krealloc(dma->buflist,
1096 				(dma->buf_count + entry->buf_count) *
1097 				sizeof(*dma->buflist), GFP_KERNEL);
1098 	if (!temp_buflist) {
1099 		/* Free the entry because it isn't valid */
1100 		drm_cleanup_buf_error(dev, entry);
1101 		kfree(temp_pagelist);
1102 		mutex_unlock(&dev->struct_mutex);
1103 		atomic_dec(&dev->buf_alloc);
1104 		return -ENOMEM;
1105 	}
1106 	dma->buflist = temp_buflist;
1107 
1108 	for (i = 0; i < entry->buf_count; i++) {
1109 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1110 	}
1111 
1112 	/* No allocations failed, so now we can replace the original pagelist
1113 	 * with the new one.
1114 	 */
1115 	if (dma->page_count) {
1116 		kfree(dma->pagelist);
1117 	}
1118 	dma->pagelist = temp_pagelist;
1119 
1120 	dma->buf_count += entry->buf_count;
1121 	dma->seg_count += entry->seg_count;
1122 	dma->page_count += entry->seg_count << page_order;
1123 	dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
1124 
1125 	mutex_unlock(&dev->struct_mutex);
1126 
1127 	request->count = entry->buf_count;
1128 	request->size = size;
1129 
1130 	if (request->flags & _DRM_PCI_BUFFER_RO)
1131 		dma->flags = _DRM_DMA_USE_PCI_RO;
1132 
1133 	atomic_dec(&dev->buf_alloc);
1134 	return 0;
1135 
1136 }
1137 EXPORT_SYMBOL(drm_legacy_addbufs_pci);
1138 
drm_legacy_addbufs_sg(struct drm_device * dev,struct drm_buf_desc * request)1139 static int drm_legacy_addbufs_sg(struct drm_device *dev,
1140 				 struct drm_buf_desc *request)
1141 {
1142 	struct drm_device_dma *dma = dev->dma;
1143 	struct drm_buf_entry *entry;
1144 	struct drm_buf *buf;
1145 	unsigned long offset;
1146 	unsigned long agp_offset;
1147 	int count;
1148 	int order;
1149 	int size;
1150 	int alignment;
1151 	int page_order;
1152 	int total;
1153 	int byte_count;
1154 	int i;
1155 	struct drm_buf **temp_buflist;
1156 
1157 	if (!drm_core_check_feature(dev, DRIVER_SG))
1158 		return -EOPNOTSUPP;
1159 
1160 	if (!dma)
1161 		return -EINVAL;
1162 
1163 	if (!capable(CAP_SYS_ADMIN))
1164 		return -EPERM;
1165 
1166 	count = request->count;
1167 	order = order_base_2(request->size);
1168 	size = 1 << order;
1169 
1170 	alignment = (request->flags & _DRM_PAGE_ALIGN)
1171 	    ? PAGE_ALIGN(size) : size;
1172 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
1173 	total = PAGE_SIZE << page_order;
1174 
1175 	byte_count = 0;
1176 	agp_offset = request->agp_start;
1177 
1178 	DRM_DEBUG("count:      %d\n", count);
1179 	DRM_DEBUG("order:      %d\n", order);
1180 	DRM_DEBUG("size:       %d\n", size);
1181 	DRM_DEBUG("agp_offset: %lu\n", agp_offset);
1182 	DRM_DEBUG("alignment:  %d\n", alignment);
1183 	DRM_DEBUG("page_order: %d\n", page_order);
1184 	DRM_DEBUG("total:      %d\n", total);
1185 
1186 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1187 		return -EINVAL;
1188 
1189 	spin_lock(&dev->buf_lock);
1190 	if (dev->buf_use) {
1191 		spin_unlock(&dev->buf_lock);
1192 		return -EBUSY;
1193 	}
1194 	atomic_inc(&dev->buf_alloc);
1195 	spin_unlock(&dev->buf_lock);
1196 
1197 	mutex_lock(&dev->struct_mutex);
1198 	entry = &dma->bufs[order];
1199 	if (entry->buf_count) {
1200 		mutex_unlock(&dev->struct_mutex);
1201 		atomic_dec(&dev->buf_alloc);
1202 		return -ENOMEM;	/* May only call once for each order */
1203 	}
1204 
1205 	if (count < 0 || count > 4096) {
1206 		mutex_unlock(&dev->struct_mutex);
1207 		atomic_dec(&dev->buf_alloc);
1208 		return -EINVAL;
1209 	}
1210 
1211 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
1212 	if (!entry->buflist) {
1213 		mutex_unlock(&dev->struct_mutex);
1214 		atomic_dec(&dev->buf_alloc);
1215 		return -ENOMEM;
1216 	}
1217 
1218 	entry->buf_size = size;
1219 	entry->page_order = page_order;
1220 
1221 	offset = 0;
1222 
1223 	while (entry->buf_count < count) {
1224 		buf = &entry->buflist[entry->buf_count];
1225 		buf->idx = dma->buf_count + entry->buf_count;
1226 		buf->total = alignment;
1227 		buf->order = order;
1228 		buf->used = 0;
1229 
1230 		buf->offset = (dma->byte_count + offset);
1231 		buf->bus_address = agp_offset + offset;
1232 		buf->address = (void *)(agp_offset + offset
1233 					+ (unsigned long)dev->sg->virtual);
1234 		buf->next = NULL;
1235 		buf->waiting = 0;
1236 		buf->pending = 0;
1237 		buf->file_priv = NULL;
1238 
1239 		buf->dev_priv_size = dev->driver->dev_priv_size;
1240 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
1241 		if (!buf->dev_private) {
1242 			/* Set count correctly so we free the proper amount. */
1243 			entry->buf_count = count;
1244 			drm_cleanup_buf_error(dev, entry);
1245 			mutex_unlock(&dev->struct_mutex);
1246 			atomic_dec(&dev->buf_alloc);
1247 			return -ENOMEM;
1248 		}
1249 
1250 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
1251 
1252 		offset += alignment;
1253 		entry->buf_count++;
1254 		byte_count += PAGE_SIZE << page_order;
1255 	}
1256 
1257 	DRM_DEBUG("byte_count: %d\n", byte_count);
1258 
1259 	temp_buflist = krealloc(dma->buflist,
1260 				(dma->buf_count + entry->buf_count) *
1261 				sizeof(*dma->buflist), GFP_KERNEL);
1262 	if (!temp_buflist) {
1263 		/* Free the entry because it isn't valid */
1264 		drm_cleanup_buf_error(dev, entry);
1265 		mutex_unlock(&dev->struct_mutex);
1266 		atomic_dec(&dev->buf_alloc);
1267 		return -ENOMEM;
1268 	}
1269 	dma->buflist = temp_buflist;
1270 
1271 	for (i = 0; i < entry->buf_count; i++) {
1272 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1273 	}
1274 
1275 	dma->buf_count += entry->buf_count;
1276 	dma->seg_count += entry->seg_count;
1277 	dma->page_count += byte_count >> PAGE_SHIFT;
1278 	dma->byte_count += byte_count;
1279 
1280 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
1281 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
1282 
1283 	mutex_unlock(&dev->struct_mutex);
1284 
1285 	request->count = entry->buf_count;
1286 	request->size = size;
1287 
1288 	dma->flags = _DRM_DMA_USE_SG;
1289 
1290 	atomic_dec(&dev->buf_alloc);
1291 	return 0;
1292 }
1293 
1294 /**
1295  * Add buffers for DMA transfers (ioctl).
1296  *
1297  * \param inode device inode.
1298  * \param file_priv DRM file private.
1299  * \param cmd command.
1300  * \param arg pointer to a struct drm_buf_desc request.
1301  * \return zero on success or a negative number on failure.
1302  *
1303  * According with the memory type specified in drm_buf_desc::flags and the
1304  * build options, it dispatches the call either to addbufs_agp(),
1305  * addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
1306  * PCI memory respectively.
1307  */
drm_legacy_addbufs(struct drm_device * dev,void * data,struct drm_file * file_priv)1308 int drm_legacy_addbufs(struct drm_device *dev, void *data,
1309 		       struct drm_file *file_priv)
1310 {
1311 	struct drm_buf_desc *request = data;
1312 	int ret;
1313 
1314 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1315 		return -EOPNOTSUPP;
1316 
1317 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1318 		return -EOPNOTSUPP;
1319 
1320 #if IS_ENABLED(CONFIG_AGP)
1321 	if (request->flags & _DRM_AGP_BUFFER)
1322 		ret = drm_legacy_addbufs_agp(dev, request);
1323 	else
1324 #endif
1325 	if (request->flags & _DRM_SG_BUFFER)
1326 		ret = drm_legacy_addbufs_sg(dev, request);
1327 	else if (request->flags & _DRM_FB_BUFFER)
1328 		ret = -EINVAL;
1329 	else
1330 		ret = drm_legacy_addbufs_pci(dev, request);
1331 
1332 	return ret;
1333 }
1334 
1335 /**
1336  * Get information about the buffer mappings.
1337  *
1338  * This was originally mean for debugging purposes, or by a sophisticated
1339  * client library to determine how best to use the available buffers (e.g.,
1340  * large buffers can be used for image transfer).
1341  *
1342  * \param inode device inode.
1343  * \param file_priv DRM file private.
1344  * \param cmd command.
1345  * \param arg pointer to a drm_buf_info structure.
1346  * \return zero on success or a negative number on failure.
1347  *
1348  * Increments drm_device::buf_use while holding the drm_device::buf_lock
1349  * lock, preventing of allocating more buffers after this call. Information
1350  * about each requested buffer is then copied into user space.
1351  */
__drm_legacy_infobufs(struct drm_device * dev,void * data,int * p,int (* f)(void *,int,struct drm_buf_entry *))1352 int __drm_legacy_infobufs(struct drm_device *dev,
1353 			void *data, int *p,
1354 			int (*f)(void *, int, struct drm_buf_entry *))
1355 {
1356 	struct drm_device_dma *dma = dev->dma;
1357 	int i;
1358 	int count;
1359 
1360 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1361 		return -EOPNOTSUPP;
1362 
1363 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1364 		return -EOPNOTSUPP;
1365 
1366 	if (!dma)
1367 		return -EINVAL;
1368 
1369 	spin_lock(&dev->buf_lock);
1370 	if (atomic_read(&dev->buf_alloc)) {
1371 		spin_unlock(&dev->buf_lock);
1372 		return -EBUSY;
1373 	}
1374 	++dev->buf_use;		/* Can't allocate more after this call */
1375 	spin_unlock(&dev->buf_lock);
1376 
1377 	for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1378 		if (dma->bufs[i].buf_count)
1379 			++count;
1380 	}
1381 
1382 	DRM_DEBUG("count = %d\n", count);
1383 
1384 	if (*p >= count) {
1385 		for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1386 			struct drm_buf_entry *from = &dma->bufs[i];
1387 			if (from->buf_count) {
1388 				if (f(data, count, from) < 0)
1389 					return -EFAULT;
1390 				DRM_DEBUG("%d %d %d %d %d\n",
1391 					  i,
1392 					  dma->bufs[i].buf_count,
1393 					  dma->bufs[i].buf_size,
1394 					  dma->bufs[i].low_mark,
1395 					  dma->bufs[i].high_mark);
1396 				++count;
1397 			}
1398 		}
1399 	}
1400 	*p = count;
1401 
1402 	return 0;
1403 }
1404 
copy_one_buf(void * data,int count,struct drm_buf_entry * from)1405 static int copy_one_buf(void *data, int count, struct drm_buf_entry *from)
1406 {
1407 	struct drm_buf_info *request = data;
1408 	struct drm_buf_desc __user *to = &request->list[count];
1409 	struct drm_buf_desc v = {.count = from->buf_count,
1410 				 .size = from->buf_size,
1411 				 .low_mark = from->low_mark,
1412 				 .high_mark = from->high_mark};
1413 
1414 	if (copy_to_user(to, &v, offsetof(struct drm_buf_desc, flags)))
1415 		return -EFAULT;
1416 	return 0;
1417 }
1418 
drm_legacy_infobufs(struct drm_device * dev,void * data,struct drm_file * file_priv)1419 int drm_legacy_infobufs(struct drm_device *dev, void *data,
1420 			struct drm_file *file_priv)
1421 {
1422 	struct drm_buf_info *request = data;
1423 	return __drm_legacy_infobufs(dev, data, &request->count, copy_one_buf);
1424 }
1425 
1426 /**
1427  * Specifies a low and high water mark for buffer allocation
1428  *
1429  * \param inode device inode.
1430  * \param file_priv DRM file private.
1431  * \param cmd command.
1432  * \param arg a pointer to a drm_buf_desc structure.
1433  * \return zero on success or a negative number on failure.
1434  *
1435  * Verifies that the size order is bounded between the admissible orders and
1436  * updates the respective drm_device_dma::bufs entry low and high water mark.
1437  *
1438  * \note This ioctl is deprecated and mostly never used.
1439  */
drm_legacy_markbufs(struct drm_device * dev,void * data,struct drm_file * file_priv)1440 int drm_legacy_markbufs(struct drm_device *dev, void *data,
1441 			struct drm_file *file_priv)
1442 {
1443 	struct drm_device_dma *dma = dev->dma;
1444 	struct drm_buf_desc *request = data;
1445 	int order;
1446 	struct drm_buf_entry *entry;
1447 
1448 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1449 		return -EOPNOTSUPP;
1450 
1451 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1452 		return -EOPNOTSUPP;
1453 
1454 	if (!dma)
1455 		return -EINVAL;
1456 
1457 	DRM_DEBUG("%d, %d, %d\n",
1458 		  request->size, request->low_mark, request->high_mark);
1459 	order = order_base_2(request->size);
1460 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1461 		return -EINVAL;
1462 	entry = &dma->bufs[order];
1463 
1464 	if (request->low_mark < 0 || request->low_mark > entry->buf_count)
1465 		return -EINVAL;
1466 	if (request->high_mark < 0 || request->high_mark > entry->buf_count)
1467 		return -EINVAL;
1468 
1469 	entry->low_mark = request->low_mark;
1470 	entry->high_mark = request->high_mark;
1471 
1472 	return 0;
1473 }
1474 
1475 /**
1476  * Unreserve the buffers in list, previously reserved using drmDMA.
1477  *
1478  * \param inode device inode.
1479  * \param file_priv DRM file private.
1480  * \param cmd command.
1481  * \param arg pointer to a drm_buf_free structure.
1482  * \return zero on success or a negative number on failure.
1483  *
1484  * Calls free_buffer() for each used buffer.
1485  * This function is primarily used for debugging.
1486  */
drm_legacy_freebufs(struct drm_device * dev,void * data,struct drm_file * file_priv)1487 int drm_legacy_freebufs(struct drm_device *dev, void *data,
1488 			struct drm_file *file_priv)
1489 {
1490 	struct drm_device_dma *dma = dev->dma;
1491 	struct drm_buf_free *request = data;
1492 	int i;
1493 	int idx;
1494 	struct drm_buf *buf;
1495 
1496 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1497 		return -EOPNOTSUPP;
1498 
1499 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1500 		return -EOPNOTSUPP;
1501 
1502 	if (!dma)
1503 		return -EINVAL;
1504 
1505 	DRM_DEBUG("%d\n", request->count);
1506 	for (i = 0; i < request->count; i++) {
1507 		if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
1508 			return -EFAULT;
1509 		if (idx < 0 || idx >= dma->buf_count) {
1510 			DRM_ERROR("Index %d (of %d max)\n",
1511 				  idx, dma->buf_count - 1);
1512 			return -EINVAL;
1513 		}
1514 		idx = array_index_nospec(idx, dma->buf_count);
1515 		buf = dma->buflist[idx];
1516 		if (buf->file_priv != file_priv) {
1517 #ifdef __NetBSD__
1518 			DRM_ERROR("Process %d freeing buffer not owned\n",
1519 				  (int)curproc->p_pid);
1520 #else
1521 			DRM_ERROR("Process %d freeing buffer not owned\n",
1522 				  task_pid_nr(current));
1523 #endif
1524 			return -EINVAL;
1525 		}
1526 		drm_legacy_free_buffer(dev, buf);
1527 	}
1528 
1529 	return 0;
1530 }
1531 
1532 /**
1533  * Maps all of the DMA buffers into client-virtual space (ioctl).
1534  *
1535  * \param inode device inode.
1536  * \param file_priv DRM file private.
1537  * \param cmd command.
1538  * \param arg pointer to a drm_buf_map structure.
1539  * \return zero on success or a negative number on failure.
1540  *
1541  * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information
1542  * about each buffer into user space. For PCI buffers, it calls vm_mmap() with
1543  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
1544  * drm_mmap_dma().
1545  */
__drm_legacy_mapbufs(struct drm_device * dev,void * data,int * p,void __user ** v,int (* f)(void *,int,unsigned long,struct drm_buf *),struct drm_file * file_priv)1546 int __drm_legacy_mapbufs(struct drm_device *dev, void *data, int *p,
1547 			 void __user **v,
1548 			 int (*f)(void *, int, unsigned long,
1549 				 struct drm_buf *),
1550 				 struct drm_file *file_priv)
1551 {
1552 	struct drm_device_dma *dma = dev->dma;
1553 	int retcode = 0;
1554 	unsigned long virtual;
1555 	int i;
1556 
1557 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1558 		return -EOPNOTSUPP;
1559 
1560 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1561 		return -EOPNOTSUPP;
1562 
1563 	if (!dma)
1564 		return -EINVAL;
1565 
1566 	spin_lock(&dev->buf_lock);
1567 	if (atomic_read(&dev->buf_alloc)) {
1568 		spin_unlock(&dev->buf_lock);
1569 		return -EBUSY;
1570 	}
1571 	dev->buf_use++;		/* Can't allocate more after this call */
1572 	spin_unlock(&dev->buf_lock);
1573 
1574 	if (*p >= dma->buf_count) {
1575 		if ((dev->agp && (dma->flags & _DRM_DMA_USE_AGP))
1576 		    || (drm_core_check_feature(dev, DRIVER_SG)
1577 			&& (dma->flags & _DRM_DMA_USE_SG))) {
1578 			struct drm_local_map *map = dev->agp_buffer_map;
1579 			unsigned long token = dev->agp_buffer_token;
1580 
1581 			if (!map) {
1582 				retcode = -EINVAL;
1583 				goto done;
1584 			}
1585 			virtual = vm_mmap(file_priv->filp, 0, map->size,
1586 					  PROT_READ | PROT_WRITE,
1587 					  MAP_SHARED,
1588 					  token);
1589 		} else {
1590 			virtual = vm_mmap(file_priv->filp, 0, dma->byte_count,
1591 					  PROT_READ | PROT_WRITE,
1592 					  MAP_SHARED, 0);
1593 		}
1594 		if (virtual > -1024UL) {
1595 			/* Real error */
1596 			retcode = (signed long)virtual;
1597 			goto done;
1598 		}
1599 		*v = (void __user *)virtual;
1600 
1601 		for (i = 0; i < dma->buf_count; i++) {
1602 			if (f(data, i, virtual, dma->buflist[i]) < 0) {
1603 				retcode = -EFAULT;
1604 				goto done;
1605 			}
1606 		}
1607 	}
1608       done:
1609 	*p = dma->buf_count;
1610 	DRM_DEBUG("%d buffers, retcode = %d\n", *p, retcode);
1611 
1612 	return retcode;
1613 }
1614 
map_one_buf(void * data,int idx,unsigned long virtual,struct drm_buf * buf)1615 static int map_one_buf(void *data, int idx, unsigned long virtual,
1616 			struct drm_buf *buf)
1617 {
1618 	struct drm_buf_map *request = data;
1619 	unsigned long address = virtual + buf->offset;	/* *** */
1620 
1621 	if (copy_to_user(&request->list[idx].idx, &buf->idx,
1622 			 sizeof(request->list[0].idx)))
1623 		return -EFAULT;
1624 	if (copy_to_user(&request->list[idx].total, &buf->total,
1625 			 sizeof(request->list[0].total)))
1626 		return -EFAULT;
1627 	if (clear_user(&request->list[idx].used, sizeof(int)))
1628 		return -EFAULT;
1629 	if (copy_to_user(&request->list[idx].address, &address,
1630 			 sizeof(address)))
1631 		return -EFAULT;
1632 	return 0;
1633 }
1634 
drm_legacy_mapbufs(struct drm_device * dev,void * data,struct drm_file * file_priv)1635 int drm_legacy_mapbufs(struct drm_device *dev, void *data,
1636 		       struct drm_file *file_priv)
1637 {
1638 	struct drm_buf_map *request = data;
1639 	return __drm_legacy_mapbufs(dev, data, &request->count,
1640 				    &request->virtual, map_one_buf,
1641 				    file_priv);
1642 }
1643 
drm_legacy_dma_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)1644 int drm_legacy_dma_ioctl(struct drm_device *dev, void *data,
1645 		  struct drm_file *file_priv)
1646 {
1647 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1648 		return -EOPNOTSUPP;
1649 
1650 	if (dev->driver->dma_ioctl)
1651 		return dev->driver->dma_ioctl(dev, data, file_priv);
1652 	else
1653 		return -EINVAL;
1654 }
1655 
drm_legacy_getsarea(struct drm_device * dev)1656 struct drm_local_map *drm_legacy_getsarea(struct drm_device *dev)
1657 {
1658 	struct drm_map_list *entry;
1659 
1660 	list_for_each_entry(entry, &dev->maplist, head) {
1661 		if (entry->map && entry->map->type == _DRM_SHM &&
1662 		    (entry->map->flags & _DRM_CONTAINS_LOCK)) {
1663 			return entry->map;
1664 		}
1665 	}
1666 	return NULL;
1667 }
1668 EXPORT_SYMBOL(drm_legacy_getsarea);
1669