xref: /dragonfly/sys/dev/drm/drm_bufs.c (revision 0de61e28)
1 /*
2  * Legacy: Generic DRM Buffer Management
3  *
4  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
5  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6  * All Rights Reserved.
7  *
8  * Author: Rickard E. (Rik) Faith <faith@valinux.com>
9  * Author: Gareth Hughes <gareth@valinux.com>
10  *
11  * Permission is hereby granted, free of charge, to any person obtaining a
12  * copy of this software and associated documentation files (the "Software"),
13  * to deal in the Software without restriction, including without limitation
14  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15  * and/or sell copies of the Software, and to permit persons to whom the
16  * Software is furnished to do so, subject to the following conditions:
17  *
18  * The above copyright notice and this permission notice (including the next
19  * paragraph) shall be included in all copies or substantial portions of the
20  * Software.
21  *
22  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
25  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
26  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28  * OTHER DEALINGS IN THE SOFTWARE.
29  */
30 
31 #include <linux/vmalloc.h>
32 #include <linux/log2.h>
33 #include <linux/export.h>
34 #include <asm/shmparam.h>
35 #include <drm/drmP.h>
36 #include "drm_legacy.h"
37 
38 #include <sys/conf.h>
39 #include <sys/mman.h>
40 #include <vm/vm_map.h>
41 
42 static struct drm_map_list *drm_find_matching_map(struct drm_device *dev,
43 						  struct drm_local_map *map)
44 {
45 	struct drm_map_list *entry;
46 	list_for_each_entry(entry, &dev->maplist, head) {
47 		/*
48 		 * Because the kernel-userspace ABI is fixed at a 32-bit offset
49 		 * while PCI resources may live above that, we only compare the
50 		 * lower 32 bits of the map offset for maps of type
51 		 * _DRM_FRAMEBUFFER or _DRM_REGISTERS.
52 		 * It is assumed that if a driver have more than one resource
53 		 * of each type, the lower 32 bits are different.
54 		 */
55 		if (!entry->map ||
56 		    map->type != entry->map->type ||
57 		    entry->master != dev->master)
58 			continue;
59 		switch (map->type) {
60 		case _DRM_SHM:
61 			if (map->flags != _DRM_CONTAINS_LOCK)
62 				break;
63 			return entry;
64 		case _DRM_REGISTERS:
65 		case _DRM_FRAME_BUFFER:
66 			if ((entry->map->offset & 0xffffffff) ==
67 			    (map->offset & 0xffffffff))
68 				return entry;
69 		default: /* Make gcc happy */
70 			;
71 		}
72 		if (entry->map->offset == map->offset)
73 			return entry;
74 	}
75 
76 	return NULL;
77 }
78 
79 static int drm_map_handle(struct drm_device *dev, struct drm_hash_item *hash,
80 			  unsigned long user_token, int hashed_handle, int shm)
81 {
82 	int use_hashed_handle, shift;
83 	unsigned long add;
84 
85 #if (BITS_PER_LONG == 64)
86 	use_hashed_handle = ((user_token & 0xFFFFFFFF00000000UL) || hashed_handle);
87 #elif (BITS_PER_LONG == 32)
88 	use_hashed_handle = hashed_handle;
89 #else
90 #error Unsupported long size. Neither 64 nor 32 bits.
91 #endif
92 
93 	if (!use_hashed_handle) {
94 		int ret;
95 		hash->key = user_token >> PAGE_SHIFT;
96 		ret = drm_ht_insert_item(&dev->map_hash, hash);
97 		if (ret != -EINVAL)
98 			return ret;
99 	}
100 
101 	shift = 0;
102 	add = DRM_MAP_HASH_OFFSET >> PAGE_SHIFT;
103 	if (shm && (SHMLBA > PAGE_SIZE)) {
104 		int bits = ilog2(SHMLBA >> PAGE_SHIFT) + 1;
105 
106 		/* For shared memory, we have to preserve the SHMLBA
107 		 * bits of the eventual vma->vm_pgoff value during
108 		 * mmap().  Otherwise we run into cache aliasing problems
109 		 * on some platforms.  On these platforms, the pgoff of
110 		 * a mmap() request is used to pick a suitable virtual
111 		 * address for the mmap() region such that it will not
112 		 * cause cache aliasing problems.
113 		 *
114 		 * Therefore, make sure the SHMLBA relevant bits of the
115 		 * hash value we use are equal to those in the original
116 		 * kernel virtual address.
117 		 */
118 		shift = bits;
119 		add |= ((user_token >> PAGE_SHIFT) & ((1UL << bits) - 1UL));
120 	}
121 
122 	return drm_ht_just_insert_please(&dev->map_hash, hash,
123 					 user_token, 32 - PAGE_SHIFT - 3,
124 					 shift, add);
125 }
126 
127 /**
128  * Core function to create a range of memory available for mapping by a
129  * non-root process.
130  *
131  * Adjusts the memory offset to its absolute value according to the mapping
132  * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
133  * applicable and if supported by the kernel.
134  */
135 static int drm_addmap_core(struct drm_device * dev, resource_size_t offset,
136 			   unsigned int size, enum drm_map_type type,
137 			   enum drm_map_flags flags,
138 			   struct drm_map_list ** maplist)
139 {
140 	struct drm_local_map *map;
141 	struct drm_map_list *list;
142 	drm_dma_handle_t *dmah;
143 	unsigned long user_token;
144 	int ret;
145 
146 	map = kmalloc(sizeof(*map), M_DRM, M_WAITOK);
147 	if (!map)
148 		return -ENOMEM;
149 
150 	map->offset = offset;
151 	map->size = size;
152 	map->flags = flags;
153 	map->type = type;
154 
155 	/* Only allow shared memory to be removable since we only keep enough
156 	 * book keeping information about shared memory to allow for removal
157 	 * when processes fork.
158 	 */
159 	if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
160 		kfree(map);
161 		return -EINVAL;
162 	}
163 	DRM_DEBUG("offset = 0x%08llx, size = 0x%08lx, type = %d\n",
164 		  (unsigned long long)map->offset, map->size, map->type);
165 
166 	/* page-align _DRM_SHM maps. They are allocated here so there is no security
167 	 * hole created by that and it works around various broken drivers that use
168 	 * a non-aligned quantity to map the SAREA. --BenH
169 	 */
170 	if (map->type == _DRM_SHM)
171 		map->size = PAGE_ALIGN(map->size);
172 
173 	if ((map->offset & (~(resource_size_t)LINUX_PAGE_MASK)) || (map->size & (~LINUX_PAGE_MASK))) {
174 		kfree(map);
175 		return -EINVAL;
176 	}
177 	map->mtrr = -1;
178 	map->handle = NULL;
179 
180 	switch (map->type) {
181 	case _DRM_REGISTERS:
182 	case _DRM_FRAME_BUFFER:
183 #if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__) && !defined(__arm__)
184 		if (map->offset + (map->size-1) < map->offset ||
185 		    map->offset < virt_to_phys(high_memory)) {
186 			kfree(map);
187 			return -EINVAL;
188 		}
189 #endif
190 		/* Some drivers preinitialize some maps, without the X Server
191 		 * needing to be aware of it.  Therefore, we just return success
192 		 * when the server tries to create a duplicate map.
193 		 */
194 		list = drm_find_matching_map(dev, map);
195 		if (list != NULL) {
196 			if (list->map->size != map->size) {
197 				DRM_DEBUG("Matching maps of type %d with "
198 					  "mismatched sizes, (%ld vs %ld)\n",
199 					  map->type, map->size,
200 					  list->map->size);
201 				list->map->size = map->size;
202 			}
203 
204 			kfree(map);
205 			*maplist = list;
206 			return 0;
207 		}
208 
209 		if (map->type == _DRM_FRAME_BUFFER ||
210 		    (map->flags & _DRM_WRITE_COMBINING)) {
211 			map->mtrr =
212 				arch_phys_wc_add(map->offset, map->size);
213 		}
214 		if (map->type == _DRM_REGISTERS) {
215 			if (map->flags & _DRM_WRITE_COMBINING)
216 				map->handle = ioremap_wc(map->offset,
217 							 map->size);
218 			else
219 				map->handle = ioremap(map->offset, map->size);
220 			if (!map->handle) {
221 				kfree(map);
222 				return -ENOMEM;
223 			}
224 		}
225 
226 		break;
227 	case _DRM_SHM:
228 		list = drm_find_matching_map(dev, map);
229 		if (list != NULL) {
230 			if(list->map->size != map->size) {
231 				DRM_DEBUG("Matching maps of type %d with "
232 					  "mismatched sizes, (%ld vs %ld)\n",
233 					  map->type, map->size, list->map->size);
234 				list->map->size = map->size;
235 			}
236 
237 			kfree(map);
238 			*maplist = list;
239 			return 0;
240 		}
241 		map->handle = vmalloc_user(map->size);
242 		DRM_DEBUG("%lu %d %p\n",
243 			  map->size, order_base_2(map->size), map->handle);
244 		if (!map->handle) {
245 			kfree(map);
246 			return -ENOMEM;
247 		}
248 		map->offset = (unsigned long)map->handle;
249 		if (map->flags & _DRM_CONTAINS_LOCK) {
250 			/* Prevent a 2nd X Server from creating a 2nd lock */
251 			if (dev->master->lock.hw_lock != NULL) {
252 				vfree(map->handle);
253 				kfree(map);
254 				return -EBUSY;
255 			}
256 			dev->sigdata.lock = dev->master->lock.hw_lock = map->handle;	/* Pointer to lock */
257 		}
258 		break;
259 	case _DRM_AGP: {
260 #if 0
261 		struct drm_agp_mem *entry;
262 		int valid = 0;
263 #endif
264 
265 		if (!dev->agp) {
266 			kfree(map);
267 			return -EINVAL;
268 		}
269 #ifdef __alpha__
270 		map->offset += dev->hose->mem_space->start;
271 #endif
272 		/* In some cases (i810 driver), user space may have already
273 		 * added the AGP base itself, because dev->agp->base previously
274 		 * only got set during AGP enable.  So, only add the base
275 		 * address if the map's offset isn't already within the
276 		 * aperture.
277 		 */
278 		if (map->offset < dev->agp->base ||
279 		    map->offset > dev->agp->base +
280 		    dev->agp->agp_info.ai_aperture_size - 1) {
281 			map->offset += dev->agp->base;
282 		}
283 		map->mtrr = dev->agp->agp_mtrr;	/* for getmap */
284 
285 		/* This assumes the DRM is in total control of AGP space.
286 		 * It's not always the case as AGP can be in the control
287 		 * of user space (i.e. i810 driver). So this loop will get
288 		 * skipped and we double check that dev->agp->memory is
289 		 * actually set as well as being invalid before EPERM'ing
290 		 */
291 #if 0
292 		list_for_each_entry(entry, &dev->agp->memory, head) {
293 			if ((map->offset >= entry->bound) &&
294 			    (map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
295 				valid = 1;
296 				break;
297 			}
298 		}
299 		if (!list_empty(&dev->agp->memory) && !valid) {
300 			kfree(map);
301 			return -EPERM;
302 		}
303 #endif
304 		DRM_DEBUG("AGP offset = 0x%08llx, size = 0x%08lx\n",
305 			  (unsigned long long)map->offset, map->size);
306 
307 		break;
308 	}
309 	case _DRM_SCATTER_GATHER:
310 		if (!dev->sg) {
311 			kfree(map);
312 			return -EINVAL;
313 		}
314 		map->handle = (void *)(uintptr_t)(dev->sg->vaddr + offset);
315 		map->offset = dev->sg->vaddr + offset;
316 		break;
317 	case _DRM_CONSISTENT:
318 		/* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
319 		 * As we're limiting the address to 2^32-1 (or less),
320 		 * casting it down to 32 bits is no problem, but we
321 		 * need to point to a 64bit variable first. */
322 		dmah = drm_pci_alloc(dev, map->size, map->size);
323 		if (!dmah) {
324 			kfree(map);
325 			return -ENOMEM;
326 		}
327 		map->handle = dmah->vaddr;
328 		map->offset = (unsigned long)dmah->busaddr;
329 		kfree(dmah);
330 		break;
331 	default:
332 		kfree(map);
333 		return -EINVAL;
334 	}
335 
336 	list = kzalloc(sizeof(*list), GFP_KERNEL);
337 	if (!list) {
338 		if (map->type == _DRM_REGISTERS)
339 			iounmap(map->handle);
340 		kfree(map);
341 		return -EINVAL;
342 	}
343 	list->map = map;
344 
345 	mutex_lock(&dev->struct_mutex);
346 	list_add(&list->head, &dev->maplist);
347 
348 	/* Assign a 32-bit handle */
349 	/* We do it here so that dev->struct_mutex protects the increment */
350 	user_token = (map->type == _DRM_SHM) ? (unsigned long)map->handle :
351 		map->offset;
352 	ret = drm_map_handle(dev, &list->hash, user_token, 0,
353 			     (map->type == _DRM_SHM));
354 	if (ret) {
355 		if (map->type == _DRM_REGISTERS)
356 			iounmap(map->handle);
357 		kfree(map);
358 		kfree(list);
359 		mutex_unlock(&dev->struct_mutex);
360 		return ret;
361 	}
362 
363 	list->user_token = list->hash.key << PAGE_SHIFT;
364 	mutex_unlock(&dev->struct_mutex);
365 
366 	if (!(map->flags & _DRM_DRIVER))
367 		list->master = dev->master;
368 	*maplist = list;
369 	return 0;
370 }
371 
372 int drm_legacy_addmap(struct drm_device * dev, resource_size_t offset,
373 		      unsigned int size, enum drm_map_type type,
374 		      enum drm_map_flags flags, struct drm_local_map **map_ptr)
375 {
376 	struct drm_map_list *list;
377 	int rc;
378 
379 	rc = drm_addmap_core(dev, offset, size, type, flags, &list);
380 	if (!rc)
381 		*map_ptr = list->map;
382 	return rc;
383 }
384 EXPORT_SYMBOL(drm_legacy_addmap);
385 
386 /**
387  * Ioctl to specify a range of memory that is available for mapping by a
388  * non-root process.
389  *
390  * \param inode device inode.
391  * \param file_priv DRM file private.
392  * \param cmd command.
393  * \param arg pointer to a drm_map structure.
394  * \return zero on success or a negative value on error.
395  *
396  */
397 int drm_legacy_addmap_ioctl(struct drm_device *dev, void *data,
398 			    struct drm_file *file_priv)
399 {
400 	struct drm_map *map = data;
401 	struct drm_map_list *maplist;
402 	int err;
403 
404 	if (!(capable(CAP_SYS_ADMIN) || map->type == _DRM_AGP || map->type == _DRM_SHM))
405 		return -EPERM;
406 
407 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
408 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
409 		return -EINVAL;
410 
411 	err = drm_addmap_core(dev, map->offset, map->size, map->type,
412 			      map->flags, &maplist);
413 
414 	if (err)
415 		return err;
416 
417 	/* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
418 	map->handle = (void *)(unsigned long)maplist->user_token;
419 
420 	/*
421 	 * It appears that there are no users of this value whatsoever --
422 	 * drmAddMap just discards it.  Let's not encourage its use.
423 	 * (Keeping drm_addmap_core's returned mtrr value would be wrong --
424 	 *  it's not a real mtrr index anymore.)
425 	 */
426 	map->mtrr = -1;
427 
428 	return 0;
429 }
430 
431 /*
432  * Get a mapping information.
433  *
434  * \param inode device inode.
435  * \param file_priv DRM file private.
436  * \param cmd command.
437  * \param arg user argument, pointing to a drm_map structure.
438  *
439  * \return zero on success or a negative number on failure.
440  *
441  * Searches for the mapping with the specified offset and copies its information
442  * into userspace
443  */
444 int drm_legacy_getmap_ioctl(struct drm_device *dev, void *data,
445 			    struct drm_file *file_priv)
446 {
447 	struct drm_map *map = data;
448 	struct drm_map_list *r_list = NULL;
449 	struct list_head *list;
450 	int idx;
451 	int i;
452 
453 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
454 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
455 		return -EINVAL;
456 
457 	idx = map->offset;
458 	if (idx < 0)
459 		return -EINVAL;
460 
461 	i = 0;
462 	mutex_lock(&dev->struct_mutex);
463 	list_for_each(list, &dev->maplist) {
464 		if (i == idx) {
465 			r_list = list_entry(list, struct drm_map_list, head);
466 			break;
467 		}
468 		i++;
469 	}
470 	if (!r_list || !r_list->map) {
471 		mutex_unlock(&dev->struct_mutex);
472 		return -EINVAL;
473 	}
474 
475 	map->offset = r_list->map->offset;
476 	map->size = r_list->map->size;
477 	map->type = r_list->map->type;
478 	map->flags = r_list->map->flags;
479 	map->handle = (void *)(unsigned long) r_list->user_token;
480 	map->mtrr = r_list->map->mtrr;
481 
482 	mutex_unlock(&dev->struct_mutex);
483 
484 	return 0;
485 }
486 
487 /**
488  * Remove a map private from list and deallocate resources if the mapping
489  * isn't in use.
490  *
491  * Searches the map on drm_device::maplist, removes it from the list, see if
492  * its being used, and free any associate resource (such as MTRR's) if it's not
493  * being on use.
494  *
495  * \sa drm_legacy_addmap
496  */
497 int drm_legacy_rmmap_locked(struct drm_device *dev, struct drm_local_map *map)
498 {
499 	struct drm_map_list *r_list = NULL, *list_t;
500 	drm_dma_handle_t dmah;
501 	int found = 0;
502 	struct drm_master *master;
503 
504 	/* Find the list entry for the map and remove it */
505 	list_for_each_entry_safe(r_list, list_t, &dev->maplist, head) {
506 		if (r_list->map == map) {
507 			master = r_list->master;
508 			list_del(&r_list->head);
509 			drm_ht_remove_key(&dev->map_hash,
510 					  r_list->user_token >> PAGE_SHIFT);
511 			kfree(r_list);
512 			found = 1;
513 			break;
514 		}
515 	}
516 
517 	if (!found)
518 		return -EINVAL;
519 
520 	switch (map->type) {
521 	case _DRM_REGISTERS:
522 		iounmap(map->handle);
523 		/* FALLTHROUGH */
524 	case _DRM_FRAME_BUFFER:
525 		arch_phys_wc_del(map->mtrr);
526 		break;
527 	case _DRM_SHM:
528 		vfree(map->handle);
529 		if (master) {
530 			if (dev->sigdata.lock == master->lock.hw_lock)
531 				dev->sigdata.lock = NULL;
532 			master->lock.hw_lock = NULL;   /* SHM removed */
533 			master->lock.file_priv = NULL;
534 			wake_up_interruptible_all(&master->lock.lock_queue);
535 		}
536 		break;
537 	case _DRM_AGP:
538 	case _DRM_SCATTER_GATHER:
539 		break;
540 	case _DRM_CONSISTENT:
541 		dmah.vaddr = map->handle;
542 		dmah.busaddr = map->offset;
543 		dmah.size = map->size;
544 		__drm_legacy_pci_free(dev, &dmah);
545 		break;
546 	}
547 	kfree(map);
548 
549 	return 0;
550 }
551 EXPORT_SYMBOL(drm_legacy_rmmap_locked);
552 
553 void drm_legacy_rmmap(struct drm_device *dev, struct drm_local_map *map)
554 {
555 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
556 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
557 		return;
558 
559 	mutex_lock(&dev->struct_mutex);
560 	drm_legacy_rmmap_locked(dev, map);
561 	mutex_unlock(&dev->struct_mutex);
562 }
563 EXPORT_SYMBOL(drm_legacy_rmmap);
564 
565 void drm_legacy_master_rmmaps(struct drm_device *dev, struct drm_master *master)
566 {
567 	struct drm_map_list *r_list, *list_temp;
568 
569 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
570 		return;
571 
572 	mutex_lock(&dev->struct_mutex);
573 	list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
574 		if (r_list->master == master) {
575 			drm_legacy_rmmap_locked(dev, r_list->map);
576 			r_list = NULL;
577 		}
578 	}
579 	mutex_unlock(&dev->struct_mutex);
580 }
581 
582 /* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
583  * the last close of the device, and this is necessary for cleanup when things
584  * exit uncleanly.  Therefore, having userland manually remove mappings seems
585  * like a pointless exercise since they're going away anyway.
586  *
587  * One use case might be after addmap is allowed for normal users for SHM and
588  * gets used by drivers that the server doesn't need to care about.  This seems
589  * unlikely.
590  *
591  * \param inode device inode.
592  * \param file_priv DRM file private.
593  * \param cmd command.
594  * \param arg pointer to a struct drm_map structure.
595  * \return zero on success or a negative value on error.
596  */
597 int drm_legacy_rmmap_ioctl(struct drm_device *dev, void *data,
598 			   struct drm_file *file_priv)
599 {
600 	struct drm_map *request = data;
601 	struct drm_local_map *map = NULL;
602 	struct drm_map_list *r_list;
603 	int ret;
604 
605 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
606 	    !drm_core_check_feature(dev, DRIVER_LEGACY))
607 		return -EINVAL;
608 
609 	mutex_lock(&dev->struct_mutex);
610 	list_for_each_entry(r_list, &dev->maplist, head) {
611 		if (r_list->map &&
612 		    r_list->user_token == (unsigned long)request->handle &&
613 		    r_list->map->flags & _DRM_REMOVABLE) {
614 			map = r_list->map;
615 			break;
616 		}
617 	}
618 
619 	/* List has wrapped around to the head pointer, or its empty we didn't
620 	 * find anything.
621 	 */
622 	if (list_empty(&dev->maplist) || !map) {
623 		mutex_unlock(&dev->struct_mutex);
624 		return -EINVAL;
625 	}
626 
627 	/* Register and framebuffer maps are permanent */
628 	if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
629 		mutex_unlock(&dev->struct_mutex);
630 		return 0;
631 	}
632 
633 	ret = drm_legacy_rmmap_locked(dev, map);
634 
635 	mutex_unlock(&dev->struct_mutex);
636 
637 	return ret;
638 }
639 
640 /**
641  * Cleanup after an error on one of the addbufs() functions.
642  *
643  * \param dev DRM device.
644  * \param entry buffer entry where the error occurred.
645  *
646  * Frees any pages and buffers associated with the given entry.
647  */
648 static void drm_cleanup_buf_error(struct drm_device * dev,
649 				  struct drm_buf_entry * entry)
650 {
651 	int i;
652 
653 	if (entry->seg_count) {
654 		for (i = 0; i < entry->seg_count; i++) {
655 			if (entry->seglist[i]) {
656 				drm_pci_free(dev, entry->seglist[i]);
657 			}
658 		}
659 		kfree(entry->seglist);
660 
661 		entry->seg_count = 0;
662 	}
663 
664 	if (entry->buf_count) {
665 		for (i = 0; i < entry->buf_count; i++) {
666 			kfree(entry->buflist[i].dev_private);
667 		}
668 		kfree(entry->buflist);
669 
670 		entry->buf_count = 0;
671 	}
672 }
673 
674 #if IS_ENABLED(CONFIG_AGP)
675 /**
676  * Add AGP buffers for DMA transfers.
677  *
678  * \param dev struct drm_device to which the buffers are to be added.
679  * \param request pointer to a struct drm_buf_desc describing the request.
680  * \return zero on success or a negative number on failure.
681  *
682  * After some sanity checks creates a drm_buf structure for each buffer and
683  * reallocates the buffer list of the same size order to accommodate the new
684  * buffers.
685  */
686 int drm_legacy_addbufs_agp(struct drm_device *dev,
687 			   struct drm_buf_desc *request)
688 {
689 	struct drm_device_dma *dma = dev->dma;
690 	struct drm_buf_entry *entry;
691 	/* struct drm_agp_mem *agp_entry; */
692 	struct drm_buf *buf;
693 	unsigned long offset;
694 	unsigned long agp_offset;
695 	int count;
696 	int order;
697 	int size;
698 	int alignment;
699 	int page_order;
700 	int total;
701 	int byte_count;
702 #if 0
703 	int i, valid;
704 #else
705 	int i;
706 #endif
707 
708 	struct drm_buf **temp_buflist;
709 
710 	if (!dma)
711 		return -EINVAL;
712 
713 	count = request->count;
714 	order = order_base_2(request->size);
715 	size = 1 << order;
716 
717 	alignment = (request->flags & _DRM_PAGE_ALIGN)
718 	    ? PAGE_ALIGN(size) : size;
719 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
720 	total = PAGE_SIZE << page_order;
721 
722 	byte_count = 0;
723 	agp_offset = dev->agp->base + request->agp_start;
724 
725 	DRM_DEBUG("count:      %d\n", count);
726 	DRM_DEBUG("order:      %d\n", order);
727 	DRM_DEBUG("size:       %d\n", size);
728 	DRM_DEBUG("agp_offset: %lx\n", agp_offset);
729 	DRM_DEBUG("alignment:  %d\n", alignment);
730 	DRM_DEBUG("page_order: %d\n", page_order);
731 	DRM_DEBUG("total:      %d\n", total);
732 
733 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
734 		return -EINVAL;
735 
736 	/* Make sure buffers are located in AGP memory that we own */
737 #if 0
738 	valid = 0;
739 	list_for_each_entry(agp_entry, &dev->agp->memory, head) {
740 		if ((agp_offset >= agp_entry->bound) &&
741 		    (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
742 			valid = 1;
743 			break;
744 		}
745 	}
746 	if (!list_empty(&dev->agp->memory) && !valid) {
747 		DRM_DEBUG("zone invalid\n");
748 		return -EINVAL;
749 	}
750 #endif
751 	lockmgr(&dev->buf_lock, LK_EXCLUSIVE);
752 	if (dev->buf_use) {
753 		lockmgr(&dev->buf_lock, LK_RELEASE);
754 		return -EBUSY;
755 	}
756 	atomic_inc(&dev->buf_alloc);
757 	lockmgr(&dev->buf_lock, LK_RELEASE);
758 
759 	mutex_lock(&dev->struct_mutex);
760 	entry = &dma->bufs[order];
761 	if (entry->buf_count) {
762 		mutex_unlock(&dev->struct_mutex);
763 		atomic_dec(&dev->buf_alloc);
764 		return -ENOMEM;	/* May only call once for each order */
765 	}
766 
767 	if (count < 0 || count > 4096) {
768 		mutex_unlock(&dev->struct_mutex);
769 		atomic_dec(&dev->buf_alloc);
770 		return -EINVAL;
771 	}
772 
773 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
774 	if (!entry->buflist) {
775 		mutex_unlock(&dev->struct_mutex);
776 		atomic_dec(&dev->buf_alloc);
777 		return -ENOMEM;
778 	}
779 
780 	entry->buf_size = size;
781 	entry->page_order = page_order;
782 
783 	offset = 0;
784 
785 	while (entry->buf_count < count) {
786 		buf = &entry->buflist[entry->buf_count];
787 		buf->idx = dma->buf_count + entry->buf_count;
788 		buf->total = alignment;
789 		buf->order = order;
790 		buf->used = 0;
791 
792 		buf->offset = (dma->byte_count + offset);
793 		buf->bus_address = agp_offset + offset;
794 		buf->address = (void *)(agp_offset + offset);
795 		buf->next = NULL;
796 		buf->waiting = 0;
797 		buf->pending = 0;
798 		buf->file_priv = NULL;
799 
800 		buf->dev_priv_size = dev->driver->dev_priv_size;
801 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
802 		if (!buf->dev_private) {
803 			/* Set count correctly so we free the proper amount. */
804 			entry->buf_count = count;
805 			drm_cleanup_buf_error(dev, entry);
806 			mutex_unlock(&dev->struct_mutex);
807 			atomic_dec(&dev->buf_alloc);
808 			return -ENOMEM;
809 		}
810 
811 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
812 
813 		offset += alignment;
814 		entry->buf_count++;
815 		byte_count += PAGE_SIZE << page_order;
816 	}
817 
818 	DRM_DEBUG("byte_count: %d\n", byte_count);
819 
820 	temp_buflist = krealloc(dma->buflist,
821 				(dma->buf_count + entry->buf_count) *
822 				sizeof(*dma->buflist), M_DRM, M_WAITOK);
823 	if (!temp_buflist) {
824 		/* Free the entry because it isn't valid */
825 		drm_cleanup_buf_error(dev, entry);
826 		mutex_unlock(&dev->struct_mutex);
827 		atomic_dec(&dev->buf_alloc);
828 		return -ENOMEM;
829 	}
830 	dma->buflist = temp_buflist;
831 
832 	for (i = 0; i < entry->buf_count; i++) {
833 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
834 	}
835 
836 	dma->buf_count += entry->buf_count;
837 	dma->seg_count += entry->seg_count;
838 	dma->page_count += byte_count >> PAGE_SHIFT;
839 	dma->byte_count += byte_count;
840 
841 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
842 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
843 
844 	mutex_unlock(&dev->struct_mutex);
845 
846 	request->count = entry->buf_count;
847 	request->size = size;
848 
849 	dma->flags = _DRM_DMA_USE_AGP;
850 
851 	atomic_dec(&dev->buf_alloc);
852 	return 0;
853 }
854 EXPORT_SYMBOL(drm_legacy_addbufs_agp);
855 #endif /* CONFIG_AGP */
856 
857 int drm_legacy_addbufs_pci(struct drm_device *dev,
858 			   struct drm_buf_desc *request)
859 {
860 	struct drm_device_dma *dma = dev->dma;
861 	int count;
862 	int order;
863 	int size;
864 	int total;
865 	int page_order;
866 	struct drm_buf_entry *entry;
867 	drm_dma_handle_t *dmah;
868 	struct drm_buf *buf;
869 	int alignment;
870 	unsigned long offset;
871 	int i;
872 	int byte_count;
873 	int page_count;
874 	unsigned long *temp_pagelist;
875 	struct drm_buf **temp_buflist;
876 
877 	if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
878 		return -EINVAL;
879 
880 	if (!dma)
881 		return -EINVAL;
882 
883 	if (!capable(CAP_SYS_ADMIN))
884 		return -EPERM;
885 
886 	count = request->count;
887 	order = order_base_2(request->size);
888 	size = 1 << order;
889 
890 	DRM_DEBUG("count=%d, size=%d (%d), order=%d\n",
891 		  request->count, request->size, size, order);
892 
893 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
894 		return -EINVAL;
895 
896 	alignment = (request->flags & _DRM_PAGE_ALIGN)
897 	    ? PAGE_ALIGN(size) : size;
898 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
899 	total = PAGE_SIZE << page_order;
900 
901 	lockmgr(&dev->buf_lock, LK_EXCLUSIVE);
902 	if (dev->buf_use) {
903 		lockmgr(&dev->buf_lock, LK_RELEASE);
904 		return -EBUSY;
905 	}
906 	atomic_inc(&dev->buf_alloc);
907 	lockmgr(&dev->buf_lock, LK_RELEASE);
908 
909 	mutex_lock(&dev->struct_mutex);
910 	entry = &dma->bufs[order];
911 	if (entry->buf_count) {
912 		mutex_unlock(&dev->struct_mutex);
913 		atomic_dec(&dev->buf_alloc);
914 		return -ENOMEM;	/* May only call once for each order */
915 	}
916 
917 	if (count < 0 || count > 4096) {
918 		mutex_unlock(&dev->struct_mutex);
919 		atomic_dec(&dev->buf_alloc);
920 		return -EINVAL;
921 	}
922 
923 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
924 	if (!entry->buflist) {
925 		mutex_unlock(&dev->struct_mutex);
926 		atomic_dec(&dev->buf_alloc);
927 		return -ENOMEM;
928 	}
929 
930 	entry->seglist = kcalloc(count, sizeof(*entry->seglist), GFP_KERNEL);
931 	if (!entry->seglist) {
932 		kfree(entry->buflist);
933 		mutex_unlock(&dev->struct_mutex);
934 		atomic_dec(&dev->buf_alloc);
935 		return -ENOMEM;
936 	}
937 
938 	/* Keep the original pagelist until we know all the allocations
939 	 * have succeeded
940 	 */
941 	temp_pagelist = kmalloc_array(dma->page_count + (count << page_order),
942 				      sizeof(*dma->pagelist),
943 				      GFP_KERNEL);
944 	if (!temp_pagelist) {
945 		kfree(entry->buflist);
946 		kfree(entry->seglist);
947 		mutex_unlock(&dev->struct_mutex);
948 		atomic_dec(&dev->buf_alloc);
949 		return -ENOMEM;
950 	}
951 	memcpy(temp_pagelist,
952 	       dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
953 	DRM_DEBUG("pagelist: %d entries\n",
954 		  dma->page_count + (count << page_order));
955 
956 	entry->buf_size = size;
957 	entry->page_order = page_order;
958 	byte_count = 0;
959 	page_count = 0;
960 
961 	while (entry->buf_count < count) {
962 
963 		dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
964 
965 		if (!dmah) {
966 			/* Set count correctly so we free the proper amount. */
967 			entry->buf_count = count;
968 			entry->seg_count = count;
969 			drm_cleanup_buf_error(dev, entry);
970 			kfree(temp_pagelist);
971 			mutex_unlock(&dev->struct_mutex);
972 			atomic_dec(&dev->buf_alloc);
973 			return -ENOMEM;
974 		}
975 		entry->seglist[entry->seg_count++] = dmah;
976 		for (i = 0; i < (1 << page_order); i++) {
977 			DRM_DEBUG("page %d @ 0x%08lx\n",
978 				  dma->page_count + page_count,
979 				  (unsigned long)dmah->vaddr + PAGE_SIZE * i);
980 			temp_pagelist[dma->page_count + page_count++]
981 				= (unsigned long)dmah->vaddr + PAGE_SIZE * i;
982 		}
983 		for (offset = 0;
984 		     offset + size <= total && entry->buf_count < count;
985 		     offset += alignment, ++entry->buf_count) {
986 			buf = &entry->buflist[entry->buf_count];
987 			buf->idx = dma->buf_count + entry->buf_count;
988 			buf->total = alignment;
989 			buf->order = order;
990 			buf->used = 0;
991 			buf->offset = (dma->byte_count + byte_count + offset);
992 			buf->address = ((char *)dmah->vaddr + offset);
993 			buf->bus_address = dmah->busaddr + offset;
994 			buf->next = NULL;
995 			buf->waiting = 0;
996 			buf->pending = 0;
997 			buf->file_priv = NULL;
998 
999 			buf->dev_priv_size = dev->driver->dev_priv_size;
1000 			buf->dev_private = kzalloc(buf->dev_priv_size,
1001 						GFP_KERNEL);
1002 			if (!buf->dev_private) {
1003 				/* Set count correctly so we free the proper amount. */
1004 				entry->buf_count = count;
1005 				entry->seg_count = count;
1006 				drm_cleanup_buf_error(dev, entry);
1007 				kfree(temp_pagelist);
1008 				mutex_unlock(&dev->struct_mutex);
1009 				atomic_dec(&dev->buf_alloc);
1010 				return -ENOMEM;
1011 			}
1012 
1013 			DRM_DEBUG("buffer %d @ %p\n",
1014 				  entry->buf_count, buf->address);
1015 		}
1016 		byte_count += PAGE_SIZE << page_order;
1017 	}
1018 
1019 	temp_buflist = krealloc(dma->buflist,
1020 				(dma->buf_count + entry->buf_count) *
1021 				sizeof(*dma->buflist), M_DRM, M_WAITOK);
1022 	if (!temp_buflist) {
1023 		/* Free the entry because it isn't valid */
1024 		drm_cleanup_buf_error(dev, entry);
1025 		kfree(temp_pagelist);
1026 		mutex_unlock(&dev->struct_mutex);
1027 		atomic_dec(&dev->buf_alloc);
1028 		return -ENOMEM;
1029 	}
1030 	dma->buflist = temp_buflist;
1031 
1032 	for (i = 0; i < entry->buf_count; i++) {
1033 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1034 	}
1035 
1036 	/* No allocations failed, so now we can replace the original pagelist
1037 	 * with the new one.
1038 	 */
1039 	if (dma->page_count) {
1040 		kfree(dma->pagelist);
1041 	}
1042 	dma->pagelist = temp_pagelist;
1043 
1044 	dma->buf_count += entry->buf_count;
1045 	dma->seg_count += entry->seg_count;
1046 	dma->page_count += entry->seg_count << page_order;
1047 	dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
1048 
1049 	mutex_unlock(&dev->struct_mutex);
1050 
1051 	request->count = entry->buf_count;
1052 	request->size = size;
1053 
1054 	if (request->flags & _DRM_PCI_BUFFER_RO)
1055 		dma->flags = _DRM_DMA_USE_PCI_RO;
1056 
1057 	atomic_dec(&dev->buf_alloc);
1058 	return 0;
1059 
1060 }
1061 EXPORT_SYMBOL(drm_legacy_addbufs_pci);
1062 
1063 static int drm_legacy_addbufs_sg(struct drm_device *dev,
1064 				 struct drm_buf_desc *request)
1065 {
1066 	struct drm_device_dma *dma = dev->dma;
1067 	struct drm_buf_entry *entry;
1068 	struct drm_buf *buf;
1069 	unsigned long offset;
1070 	unsigned long agp_offset;
1071 	int count;
1072 	int order;
1073 	int size;
1074 	int alignment;
1075 	int page_order;
1076 	int total;
1077 	int byte_count;
1078 	int i;
1079 	struct drm_buf **temp_buflist;
1080 
1081 	if (!drm_core_check_feature(dev, DRIVER_SG))
1082 		return -EINVAL;
1083 
1084 	if (!dma)
1085 		return -EINVAL;
1086 
1087 	if (!capable(CAP_SYS_ADMIN))
1088 		return -EPERM;
1089 
1090 	count = request->count;
1091 	order = order_base_2(request->size);
1092 	size = 1 << order;
1093 
1094 	alignment = (request->flags & _DRM_PAGE_ALIGN)
1095 	    ? PAGE_ALIGN(size) : size;
1096 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
1097 	total = PAGE_SIZE << page_order;
1098 
1099 	byte_count = 0;
1100 	agp_offset = request->agp_start;
1101 
1102 	DRM_DEBUG("count:      %d\n", count);
1103 	DRM_DEBUG("order:      %d\n", order);
1104 	DRM_DEBUG("size:       %d\n", size);
1105 	DRM_DEBUG("agp_offset: %lu\n", agp_offset);
1106 	DRM_DEBUG("alignment:  %d\n", alignment);
1107 	DRM_DEBUG("page_order: %d\n", page_order);
1108 	DRM_DEBUG("total:      %d\n", total);
1109 
1110 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1111 		return -EINVAL;
1112 
1113 	lockmgr(&dev->buf_lock, LK_EXCLUSIVE);
1114 	if (dev->buf_use) {
1115 		lockmgr(&dev->buf_lock, LK_RELEASE);
1116 		return -EBUSY;
1117 	}
1118 	atomic_inc(&dev->buf_alloc);
1119 	lockmgr(&dev->buf_lock, LK_RELEASE);
1120 
1121 	mutex_lock(&dev->struct_mutex);
1122 	entry = &dma->bufs[order];
1123 	if (entry->buf_count) {
1124 		mutex_unlock(&dev->struct_mutex);
1125 		atomic_dec(&dev->buf_alloc);
1126 		return -ENOMEM;	/* May only call once for each order */
1127 	}
1128 
1129 	if (count < 0 || count > 4096) {
1130 		mutex_unlock(&dev->struct_mutex);
1131 		atomic_dec(&dev->buf_alloc);
1132 		return -EINVAL;
1133 	}
1134 
1135 	entry->buflist = kcalloc(count, sizeof(*entry->buflist), GFP_KERNEL);
1136 	if (!entry->buflist) {
1137 		mutex_unlock(&dev->struct_mutex);
1138 		atomic_dec(&dev->buf_alloc);
1139 		return -ENOMEM;
1140 	}
1141 
1142 	entry->buf_size = size;
1143 	entry->page_order = page_order;
1144 
1145 	offset = 0;
1146 
1147 	while (entry->buf_count < count) {
1148 		buf = &entry->buflist[entry->buf_count];
1149 		buf->idx = dma->buf_count + entry->buf_count;
1150 		buf->total = alignment;
1151 		buf->order = order;
1152 		buf->used = 0;
1153 
1154 		buf->offset = (dma->byte_count + offset);
1155 		buf->bus_address = agp_offset + offset;
1156 		buf->address = (void *)(agp_offset + offset + dev->sg->vaddr);
1157 		buf->next = NULL;
1158 		buf->waiting = 0;
1159 		buf->pending = 0;
1160 		buf->file_priv = NULL;
1161 
1162 		buf->dev_priv_size = dev->driver->dev_priv_size;
1163 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
1164 		if (!buf->dev_private) {
1165 			/* Set count correctly so we free the proper amount. */
1166 			entry->buf_count = count;
1167 			drm_cleanup_buf_error(dev, entry);
1168 			mutex_unlock(&dev->struct_mutex);
1169 			atomic_dec(&dev->buf_alloc);
1170 			return -ENOMEM;
1171 		}
1172 
1173 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
1174 
1175 		offset += alignment;
1176 		entry->buf_count++;
1177 		byte_count += PAGE_SIZE << page_order;
1178 	}
1179 
1180 	DRM_DEBUG("byte_count: %d\n", byte_count);
1181 
1182 	temp_buflist = krealloc(dma->buflist,
1183 				(dma->buf_count + entry->buf_count) *
1184 				sizeof(*dma->buflist), M_DRM, M_WAITOK);
1185 	if (!temp_buflist) {
1186 		/* Free the entry because it isn't valid */
1187 		drm_cleanup_buf_error(dev, entry);
1188 		mutex_unlock(&dev->struct_mutex);
1189 		atomic_dec(&dev->buf_alloc);
1190 		return -ENOMEM;
1191 	}
1192 	dma->buflist = temp_buflist;
1193 
1194 	for (i = 0; i < entry->buf_count; i++) {
1195 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1196 	}
1197 
1198 	dma->buf_count += entry->buf_count;
1199 	dma->seg_count += entry->seg_count;
1200 	dma->page_count += byte_count >> PAGE_SHIFT;
1201 	dma->byte_count += byte_count;
1202 
1203 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
1204 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
1205 
1206 	mutex_unlock(&dev->struct_mutex);
1207 
1208 	request->count = entry->buf_count;
1209 	request->size = size;
1210 
1211 	dma->flags = _DRM_DMA_USE_SG;
1212 
1213 	atomic_dec(&dev->buf_alloc);
1214 	return 0;
1215 }
1216 
1217 /**
1218  * Add buffers for DMA transfers (ioctl).
1219  *
1220  * \param inode device inode.
1221  * \param file_priv DRM file private.
1222  * \param cmd command.
1223  * \param arg pointer to a struct drm_buf_desc request.
1224  * \return zero on success or a negative number on failure.
1225  *
1226  * According with the memory type specified in drm_buf_desc::flags and the
1227  * build options, it dispatches the call either to addbufs_agp(),
1228  * addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
1229  * PCI memory respectively.
1230  */
1231 int drm_legacy_addbufs(struct drm_device *dev, void *data,
1232 		       struct drm_file *file_priv)
1233 {
1234 	struct drm_buf_desc *request = data;
1235 	int ret;
1236 
1237 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1238 		return -EINVAL;
1239 
1240 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1241 		return -EINVAL;
1242 
1243 #if IS_ENABLED(CONFIG_AGP)
1244 	if (request->flags & _DRM_AGP_BUFFER)
1245 		ret = drm_legacy_addbufs_agp(dev, request);
1246 	else
1247 #endif
1248 	if (request->flags & _DRM_SG_BUFFER)
1249 		ret = drm_legacy_addbufs_sg(dev, request);
1250 	else if (request->flags & _DRM_FB_BUFFER)
1251 		ret = -EINVAL;
1252 	else
1253 		ret = drm_legacy_addbufs_pci(dev, request);
1254 
1255 	return ret;
1256 }
1257 
1258 /**
1259  * Get information about the buffer mappings.
1260  *
1261  * This was originally mean for debugging purposes, or by a sophisticated
1262  * client library to determine how best to use the available buffers (e.g.,
1263  * large buffers can be used for image transfer).
1264  *
1265  * \param inode device inode.
1266  * \param file_priv DRM file private.
1267  * \param cmd command.
1268  * \param arg pointer to a drm_buf_info structure.
1269  * \return zero on success or a negative number on failure.
1270  *
1271  * Increments drm_device::buf_use while holding the drm_device::buf_lock
1272  * lock, preventing of allocating more buffers after this call. Information
1273  * about each requested buffer is then copied into user space.
1274  */
1275 int drm_legacy_infobufs(struct drm_device *dev, void *data,
1276 			struct drm_file *file_priv)
1277 {
1278 	struct drm_device_dma *dma = dev->dma;
1279 	struct drm_buf_info *request = data;
1280 	int i;
1281 	int count;
1282 
1283 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1284 		return -EINVAL;
1285 
1286 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1287 		return -EINVAL;
1288 
1289 	if (!dma)
1290 		return -EINVAL;
1291 
1292 	lockmgr(&dev->buf_lock, LK_EXCLUSIVE);
1293 	if (atomic_read(&dev->buf_alloc)) {
1294 		lockmgr(&dev->buf_lock, LK_RELEASE);
1295 		return -EBUSY;
1296 	}
1297 	++dev->buf_use;		/* Can't allocate more after this call */
1298 	lockmgr(&dev->buf_lock, LK_RELEASE);
1299 
1300 	for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1301 		if (dma->bufs[i].buf_count)
1302 			++count;
1303 	}
1304 
1305 	DRM_DEBUG("count = %d\n", count);
1306 
1307 	if (request->count >= count) {
1308 		for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1309 			if (dma->bufs[i].buf_count) {
1310 				struct drm_buf_desc __user *to =
1311 				    &request->list[count];
1312 				struct drm_buf_entry *from = &dma->bufs[i];
1313 				if (copy_to_user(&to->count,
1314 						 &from->buf_count,
1315 						 sizeof(from->buf_count)) ||
1316 				    copy_to_user(&to->size,
1317 						 &from->buf_size,
1318 						 sizeof(from->buf_size)) ||
1319 				    copy_to_user(&to->low_mark,
1320 						 &from->low_mark,
1321 						 sizeof(from->low_mark)) ||
1322 				    copy_to_user(&to->high_mark,
1323 						 &from->high_mark,
1324 						 sizeof(from->high_mark)))
1325 					return -EFAULT;
1326 
1327 				DRM_DEBUG("%d %d %d %d %d\n",
1328 					  i,
1329 					  dma->bufs[i].buf_count,
1330 					  dma->bufs[i].buf_size,
1331 					  dma->bufs[i].low_mark,
1332 					  dma->bufs[i].high_mark);
1333 				++count;
1334 			}
1335 		}
1336 	}
1337 	request->count = count;
1338 
1339 	return 0;
1340 }
1341 
1342 /**
1343  * Specifies a low and high water mark for buffer allocation
1344  *
1345  * \param inode device inode.
1346  * \param file_priv DRM file private.
1347  * \param cmd command.
1348  * \param arg a pointer to a drm_buf_desc structure.
1349  * \return zero on success or a negative number on failure.
1350  *
1351  * Verifies that the size order is bounded between the admissible orders and
1352  * updates the respective drm_device_dma::bufs entry low and high water mark.
1353  *
1354  * \note This ioctl is deprecated and mostly never used.
1355  */
1356 int drm_legacy_markbufs(struct drm_device *dev, void *data,
1357 			struct drm_file *file_priv)
1358 {
1359 	struct drm_device_dma *dma = dev->dma;
1360 	struct drm_buf_desc *request = data;
1361 	int order;
1362 	struct drm_buf_entry *entry;
1363 
1364 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1365 		return -EINVAL;
1366 
1367 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1368 		return -EINVAL;
1369 
1370 	if (!dma)
1371 		return -EINVAL;
1372 
1373 	DRM_DEBUG("%d, %d, %d\n",
1374 		  request->size, request->low_mark, request->high_mark);
1375 	order = order_base_2(request->size);
1376 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1377 		return -EINVAL;
1378 	entry = &dma->bufs[order];
1379 
1380 	if (request->low_mark < 0 || request->low_mark > entry->buf_count)
1381 		return -EINVAL;
1382 	if (request->high_mark < 0 || request->high_mark > entry->buf_count)
1383 		return -EINVAL;
1384 
1385 	entry->low_mark = request->low_mark;
1386 	entry->high_mark = request->high_mark;
1387 
1388 	return 0;
1389 }
1390 
1391 /**
1392  * Unreserve the buffers in list, previously reserved using drmDMA.
1393  *
1394  * \param inode device inode.
1395  * \param file_priv DRM file private.
1396  * \param cmd command.
1397  * \param arg pointer to a drm_buf_free structure.
1398  * \return zero on success or a negative number on failure.
1399  *
1400  * Calls free_buffer() for each used buffer.
1401  * This function is primarily used for debugging.
1402  */
1403 int drm_legacy_freebufs(struct drm_device *dev, void *data,
1404 			struct drm_file *file_priv)
1405 {
1406 	struct drm_device_dma *dma = dev->dma;
1407 	struct drm_buf_free *request = data;
1408 	int i;
1409 	int idx;
1410 	struct drm_buf *buf;
1411 
1412 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1413 		return -EINVAL;
1414 
1415 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1416 		return -EINVAL;
1417 
1418 	if (!dma)
1419 		return -EINVAL;
1420 
1421 	DRM_DEBUG("%d\n", request->count);
1422 	for (i = 0; i < request->count; i++) {
1423 		if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
1424 			return -EFAULT;
1425 		if (idx < 0 || idx >= dma->buf_count) {
1426 			DRM_ERROR("Index %d (of %d max)\n",
1427 				  idx, dma->buf_count - 1);
1428 			return -EINVAL;
1429 		}
1430 		buf = dma->buflist[idx];
1431 		if (buf->file_priv != file_priv) {
1432 			DRM_ERROR("Process %d freeing buffer not owned\n",
1433 				  DRM_CURRENTPID);
1434 			return -EINVAL;
1435 		}
1436 		drm_legacy_free_buffer(dev, buf);
1437 	}
1438 
1439 	return 0;
1440 }
1441 
1442 /**
1443  * Maps all of the DMA buffers into client-virtual space (ioctl).
1444  *
1445  * \param inode device inode.
1446  * \param file_priv DRM file private.
1447  * \param cmd command.
1448  * \param arg pointer to a drm_buf_map structure.
1449  * \return zero on success or a negative number on failure.
1450  *
1451  * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information
1452  * about each buffer into user space. For PCI buffers, it calls vm_mmap() with
1453  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
1454  * drm_mmap_dma().
1455  */
1456 int drm_legacy_mapbufs(struct drm_device *dev, void *data,
1457 		       struct drm_file *file_priv)
1458 {
1459 	struct drm_device_dma *dma = dev->dma;
1460 	int retcode = 0;
1461 	const int zero = 0;
1462 	unsigned long virtual;
1463 	vm_offset_t address;
1464 	struct vmspace *vms  = DRM_CURPROC->td_proc->p_vmspace;
1465 	struct drm_buf_map *request = data;
1466 	int i;
1467 
1468 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1469 		return -EINVAL;
1470 
1471 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1472 		return -EINVAL;
1473 
1474 	if (!dma)
1475 		return -EINVAL;
1476 
1477 	lockmgr(&dev->buf_lock, LK_EXCLUSIVE);
1478 	if (atomic_read(&dev->buf_alloc)) {
1479 		lockmgr(&dev->buf_lock, LK_RELEASE);
1480 		return -EBUSY;
1481 	}
1482 	dev->buf_use++;		/* Can't allocate more after this call */
1483 	lockmgr(&dev->buf_lock, LK_RELEASE);
1484 
1485 	if (request->count >= dma->buf_count) {
1486 		if ((dev->agp && (dma->flags & _DRM_DMA_USE_AGP))
1487 		    || (drm_core_check_feature(dev, DRIVER_SG)
1488 			&& (dma->flags & _DRM_DMA_USE_SG))) {
1489 			struct drm_local_map *map = dev->agp_buffer_map;
1490 			unsigned long token = dev->agp_buffer_token;
1491 
1492 			if (!map) {
1493 				retcode = -EINVAL;
1494 				goto done;
1495 			}
1496 			virtual = vm_mmap(&vms->vm_map, 0, map->size,
1497 					  PROT_READ | PROT_WRITE,
1498 					  VM_PROT_ALL,
1499 					  MAP_SHARED,
1500 					  SLIST_FIRST(&dev->devnode->si_hlist),
1501 					  token);
1502 		} else {
1503 			virtual = vm_mmap(&vms->vm_map, 0, dma->byte_count,
1504 					  PROT_READ | PROT_WRITE,
1505 					  VM_PROT_ALL,
1506 					  MAP_SHARED,
1507 					  SLIST_FIRST(&dev->devnode->si_hlist),
1508 					  0);
1509 		}
1510 		if (virtual > -1024UL) {
1511 			/* Real error */
1512 			retcode = (signed long)virtual;
1513 			goto done;
1514 		}
1515 		request->virtual = (void __user *)virtual;
1516 
1517 		for (i = 0; i < dma->buf_count; i++) {
1518 			if (copy_to_user(&request->list[i].idx,
1519 					 &dma->buflist[i]->idx,
1520 					 sizeof(request->list[0].idx))) {
1521 				retcode = -EFAULT;
1522 				goto done;
1523 			}
1524 			if (copy_to_user(&request->list[i].total,
1525 					 &dma->buflist[i]->total,
1526 					 sizeof(request->list[0].total))) {
1527 				retcode = -EFAULT;
1528 				goto done;
1529 			}
1530 			if (copy_to_user(&request->list[i].used,
1531 					 &zero, sizeof(zero))) {
1532 				retcode = -EFAULT;
1533 				goto done;
1534 			}
1535 			address = virtual + dma->buflist[i]->offset;	/* *** */
1536 			if (copy_to_user(&request->list[i].address,
1537 					 &address, sizeof(address))) {
1538 				retcode = -EFAULT;
1539 				goto done;
1540 			}
1541 		}
1542 	}
1543       done:
1544 	request->count = dma->buf_count;
1545 	DRM_DEBUG("%d buffers, retcode = %d\n", request->count, retcode);
1546 
1547 	return retcode;
1548 }
1549 
1550 int drm_legacy_dma_ioctl(struct drm_device *dev, void *data,
1551 		  struct drm_file *file_priv)
1552 {
1553 	if (!drm_core_check_feature(dev, DRIVER_LEGACY))
1554 		return -EINVAL;
1555 
1556 	if (dev->driver->dma_ioctl)
1557 		return dev->driver->dma_ioctl(dev, data, file_priv);
1558 	else
1559 		return -EINVAL;
1560 }
1561 
1562 struct drm_local_map *drm_legacy_getsarea(struct drm_device *dev)
1563 {
1564 	struct drm_map_list *entry;
1565 
1566 	list_for_each_entry(entry, &dev->maplist, head) {
1567 		if (entry->map && entry->map->type == _DRM_SHM &&
1568 		    (entry->map->flags & _DRM_CONTAINS_LOCK)) {
1569 			return entry->map;
1570 		}
1571 	}
1572 	return NULL;
1573 }
1574 EXPORT_SYMBOL(drm_legacy_getsarea);
1575