xref: /dflybsd-src/sys/dev/drm/drm_bufs.c (revision d9bb5dfdc3905237fb704584b71c9e0a9627656c)
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->primary->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->primary->master->lock.hw_lock != NULL) {
252 				vfree(map->handle);
253 				kfree(map);
254 				return -EBUSY;
255 			}
256 			dev->sigdata.lock = dev->primary->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->primary->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_MODESET))
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_MODESET))
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_MODESET))
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 #if 0
566 void drm_legacy_master_rmmaps(struct drm_device *dev, struct drm_master *master)
567 {
568 	struct drm_map_list *r_list, *list_temp;
569 
570 	if (drm_core_check_feature(dev, DRIVER_MODESET))
571 		return;
572 
573 	mutex_lock(&dev->struct_mutex);
574 	list_for_each_entry_safe(r_list, list_temp, &dev->maplist, head) {
575 		if (r_list->master == master) {
576 			drm_legacy_rmmap_locked(dev, r_list->map);
577 			r_list = NULL;
578 		}
579 	}
580 	mutex_unlock(&dev->struct_mutex);
581 }
582 #endif
583 
584 /* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
585  * the last close of the device, and this is necessary for cleanup when things
586  * exit uncleanly.  Therefore, having userland manually remove mappings seems
587  * like a pointless exercise since they're going away anyway.
588  *
589  * One use case might be after addmap is allowed for normal users for SHM and
590  * gets used by drivers that the server doesn't need to care about.  This seems
591  * unlikely.
592  *
593  * \param inode device inode.
594  * \param file_priv DRM file private.
595  * \param cmd command.
596  * \param arg pointer to a struct drm_map structure.
597  * \return zero on success or a negative value on error.
598  */
599 int drm_legacy_rmmap_ioctl(struct drm_device *dev, void *data,
600 			   struct drm_file *file_priv)
601 {
602 	struct drm_map *request = data;
603 	struct drm_local_map *map = NULL;
604 	struct drm_map_list *r_list;
605 	int ret;
606 
607 	if (!drm_core_check_feature(dev, DRIVER_KMS_LEGACY_CONTEXT) &&
608 	    drm_core_check_feature(dev, DRIVER_MODESET))
609 		return -EINVAL;
610 
611 	mutex_lock(&dev->struct_mutex);
612 	list_for_each_entry(r_list, &dev->maplist, head) {
613 		if (r_list->map &&
614 		    r_list->user_token == (unsigned long)request->handle &&
615 		    r_list->map->flags & _DRM_REMOVABLE) {
616 			map = r_list->map;
617 			break;
618 		}
619 	}
620 
621 	/* List has wrapped around to the head pointer, or its empty we didn't
622 	 * find anything.
623 	 */
624 	if (list_empty(&dev->maplist) || !map) {
625 		mutex_unlock(&dev->struct_mutex);
626 		return -EINVAL;
627 	}
628 
629 	/* Register and framebuffer maps are permanent */
630 	if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
631 		mutex_unlock(&dev->struct_mutex);
632 		return 0;
633 	}
634 
635 	ret = drm_legacy_rmmap_locked(dev, map);
636 
637 	mutex_unlock(&dev->struct_mutex);
638 
639 	return ret;
640 }
641 
642 /**
643  * Cleanup after an error on one of the addbufs() functions.
644  *
645  * \param dev DRM device.
646  * \param entry buffer entry where the error occurred.
647  *
648  * Frees any pages and buffers associated with the given entry.
649  */
650 static void drm_cleanup_buf_error(struct drm_device * dev,
651 				  struct drm_buf_entry * entry)
652 {
653 	int i;
654 
655 	if (entry->seg_count) {
656 		for (i = 0; i < entry->seg_count; i++) {
657 			if (entry->seglist[i]) {
658 				drm_pci_free(dev, entry->seglist[i]);
659 			}
660 		}
661 		kfree(entry->seglist);
662 
663 		entry->seg_count = 0;
664 	}
665 
666 	if (entry->buf_count) {
667 		for (i = 0; i < entry->buf_count; i++) {
668 			kfree(entry->buflist[i].dev_private);
669 		}
670 		kfree(entry->buflist);
671 
672 		entry->buf_count = 0;
673 	}
674 }
675 
676 #if IS_ENABLED(CONFIG_AGP)
677 /**
678  * Add AGP buffers for DMA transfers.
679  *
680  * \param dev struct drm_device to which the buffers are to be added.
681  * \param request pointer to a struct drm_buf_desc describing the request.
682  * \return zero on success or a negative number on failure.
683  *
684  * After some sanity checks creates a drm_buf structure for each buffer and
685  * reallocates the buffer list of the same size order to accommodate the new
686  * buffers.
687  */
688 int drm_legacy_addbufs_agp(struct drm_device *dev,
689 			   struct drm_buf_desc *request)
690 {
691 	struct drm_device_dma *dma = dev->dma;
692 	struct drm_buf_entry *entry;
693 	/* struct drm_agp_mem *agp_entry; */
694 	struct drm_buf *buf;
695 	unsigned long offset;
696 	unsigned long agp_offset;
697 	int count;
698 	int order;
699 	int size;
700 	int alignment;
701 	int page_order;
702 	int total;
703 	int byte_count;
704 #if 0
705 	int i, valid;
706 #else
707 	int i;
708 #endif
709 
710 	struct drm_buf **temp_buflist;
711 
712 	if (!dma)
713 		return -EINVAL;
714 
715 	count = request->count;
716 	order = order_base_2(request->size);
717 	size = 1 << order;
718 
719 	alignment = (request->flags & _DRM_PAGE_ALIGN)
720 	    ? PAGE_ALIGN(size) : size;
721 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
722 	total = PAGE_SIZE << page_order;
723 
724 	byte_count = 0;
725 	agp_offset = dev->agp->base + request->agp_start;
726 
727 	DRM_DEBUG("count:      %d\n", count);
728 	DRM_DEBUG("order:      %d\n", order);
729 	DRM_DEBUG("size:       %d\n", size);
730 	DRM_DEBUG("agp_offset: %lx\n", agp_offset);
731 	DRM_DEBUG("alignment:  %d\n", alignment);
732 	DRM_DEBUG("page_order: %d\n", page_order);
733 	DRM_DEBUG("total:      %d\n", total);
734 
735 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
736 		return -EINVAL;
737 
738 	/* Make sure buffers are located in AGP memory that we own */
739 #if 0
740 	valid = 0;
741 	list_for_each_entry(agp_entry, &dev->agp->memory, head) {
742 		if ((agp_offset >= agp_entry->bound) &&
743 		    (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
744 			valid = 1;
745 			break;
746 		}
747 	}
748 	if (!list_empty(&dev->agp->memory) && !valid) {
749 		DRM_DEBUG("zone invalid\n");
750 		return -EINVAL;
751 	}
752 #endif
753 	spin_lock(&dev->buf_lock);
754 	if (dev->buf_use) {
755 		spin_unlock(&dev->buf_lock);
756 		return -EBUSY;
757 	}
758 	atomic_inc(&dev->buf_alloc);
759 	spin_unlock(&dev->buf_lock);
760 
761 	mutex_lock(&dev->struct_mutex);
762 	entry = &dma->bufs[order];
763 	if (entry->buf_count) {
764 		mutex_unlock(&dev->struct_mutex);
765 		atomic_dec(&dev->buf_alloc);
766 		return -ENOMEM;	/* May only call once for each order */
767 	}
768 
769 	if (count < 0 || count > 4096) {
770 		mutex_unlock(&dev->struct_mutex);
771 		atomic_dec(&dev->buf_alloc);
772 		return -EINVAL;
773 	}
774 
775 	entry->buflist = kzalloc(count * sizeof(*entry->buflist), GFP_KERNEL);
776 	if (!entry->buflist) {
777 		mutex_unlock(&dev->struct_mutex);
778 		atomic_dec(&dev->buf_alloc);
779 		return -ENOMEM;
780 	}
781 
782 	entry->buf_size = size;
783 	entry->page_order = page_order;
784 
785 	offset = 0;
786 
787 	while (entry->buf_count < count) {
788 		buf = &entry->buflist[entry->buf_count];
789 		buf->idx = dma->buf_count + entry->buf_count;
790 		buf->total = alignment;
791 		buf->order = order;
792 		buf->used = 0;
793 
794 		buf->offset = (dma->byte_count + offset);
795 		buf->bus_address = agp_offset + offset;
796 		buf->address = (void *)(agp_offset + offset);
797 		buf->next = NULL;
798 		buf->waiting = 0;
799 		buf->pending = 0;
800 		buf->file_priv = NULL;
801 
802 		buf->dev_priv_size = dev->driver->dev_priv_size;
803 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
804 		if (!buf->dev_private) {
805 			/* Set count correctly so we free the proper amount. */
806 			entry->buf_count = count;
807 			drm_cleanup_buf_error(dev, entry);
808 			mutex_unlock(&dev->struct_mutex);
809 			atomic_dec(&dev->buf_alloc);
810 			return -ENOMEM;
811 		}
812 
813 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
814 
815 		offset += alignment;
816 		entry->buf_count++;
817 		byte_count += PAGE_SIZE << page_order;
818 	}
819 
820 	DRM_DEBUG("byte_count: %d\n", byte_count);
821 
822 	temp_buflist = krealloc(dma->buflist,
823 				(dma->buf_count + entry->buf_count) *
824 				sizeof(*dma->buflist), M_DRM, M_WAITOK);
825 	if (!temp_buflist) {
826 		/* Free the entry because it isn't valid */
827 		drm_cleanup_buf_error(dev, entry);
828 		mutex_unlock(&dev->struct_mutex);
829 		atomic_dec(&dev->buf_alloc);
830 		return -ENOMEM;
831 	}
832 	dma->buflist = temp_buflist;
833 
834 	for (i = 0; i < entry->buf_count; i++) {
835 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
836 	}
837 
838 	dma->buf_count += entry->buf_count;
839 	dma->seg_count += entry->seg_count;
840 	dma->page_count += byte_count >> PAGE_SHIFT;
841 	dma->byte_count += byte_count;
842 
843 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
844 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
845 
846 	mutex_unlock(&dev->struct_mutex);
847 
848 	request->count = entry->buf_count;
849 	request->size = size;
850 
851 	dma->flags = _DRM_DMA_USE_AGP;
852 
853 	atomic_dec(&dev->buf_alloc);
854 	return 0;
855 }
856 EXPORT_SYMBOL(drm_legacy_addbufs_agp);
857 #endif /* CONFIG_AGP */
858 
859 int drm_legacy_addbufs_pci(struct drm_device *dev,
860 			   struct drm_buf_desc *request)
861 {
862 	struct drm_device_dma *dma = dev->dma;
863 	int count;
864 	int order;
865 	int size;
866 	int total;
867 	int page_order;
868 	struct drm_buf_entry *entry;
869 	drm_dma_handle_t *dmah;
870 	struct drm_buf *buf;
871 	int alignment;
872 	unsigned long offset;
873 	int i;
874 	int byte_count;
875 	int page_count;
876 	unsigned long *temp_pagelist;
877 	struct drm_buf **temp_buflist;
878 
879 	if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
880 		return -EINVAL;
881 
882 	if (!dma)
883 		return -EINVAL;
884 
885 	if (!capable(CAP_SYS_ADMIN))
886 		return -EPERM;
887 
888 	count = request->count;
889 	order = order_base_2(request->size);
890 	size = 1 << order;
891 
892 	DRM_DEBUG("count=%d, size=%d (%d), order=%d\n",
893 		  request->count, request->size, size, order);
894 
895 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
896 		return -EINVAL;
897 
898 	alignment = (request->flags & _DRM_PAGE_ALIGN)
899 	    ? PAGE_ALIGN(size) : size;
900 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
901 	total = PAGE_SIZE << page_order;
902 
903 	spin_lock(&dev->buf_lock);
904 	if (dev->buf_use) {
905 		spin_unlock(&dev->buf_lock);
906 		return -EBUSY;
907 	}
908 	atomic_inc(&dev->buf_alloc);
909 	spin_unlock(&dev->buf_lock);
910 
911 	mutex_lock(&dev->struct_mutex);
912 	entry = &dma->bufs[order];
913 	if (entry->buf_count) {
914 		mutex_unlock(&dev->struct_mutex);
915 		atomic_dec(&dev->buf_alloc);
916 		return -ENOMEM;	/* May only call once for each order */
917 	}
918 
919 	if (count < 0 || count > 4096) {
920 		mutex_unlock(&dev->struct_mutex);
921 		atomic_dec(&dev->buf_alloc);
922 		return -EINVAL;
923 	}
924 
925 	entry->buflist = kzalloc(count * sizeof(*entry->buflist), GFP_KERNEL);
926 	if (!entry->buflist) {
927 		mutex_unlock(&dev->struct_mutex);
928 		atomic_dec(&dev->buf_alloc);
929 		return -ENOMEM;
930 	}
931 
932 	entry->seglist = kzalloc(count * sizeof(*entry->seglist), GFP_KERNEL);
933 	if (!entry->seglist) {
934 		kfree(entry->buflist);
935 		mutex_unlock(&dev->struct_mutex);
936 		atomic_dec(&dev->buf_alloc);
937 		return -ENOMEM;
938 	}
939 
940 	/* Keep the original pagelist until we know all the allocations
941 	 * have succeeded
942 	 */
943 	temp_pagelist = kmalloc((dma->page_count + (count << page_order)) *
944 			       sizeof(*dma->pagelist), M_DRM, M_WAITOK );
945 	if (!temp_pagelist) {
946 		kfree(entry->buflist);
947 		kfree(entry->seglist);
948 		mutex_unlock(&dev->struct_mutex);
949 		atomic_dec(&dev->buf_alloc);
950 		return -ENOMEM;
951 	}
952 	memcpy(temp_pagelist,
953 	       dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
954 	DRM_DEBUG("pagelist: %d entries\n",
955 		  dma->page_count + (count << page_order));
956 
957 	entry->buf_size = size;
958 	entry->page_order = page_order;
959 	byte_count = 0;
960 	page_count = 0;
961 
962 	while (entry->buf_count < count) {
963 
964 		dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
965 
966 		if (!dmah) {
967 			/* Set count correctly so we free the proper amount. */
968 			entry->buf_count = count;
969 			entry->seg_count = count;
970 			drm_cleanup_buf_error(dev, entry);
971 			kfree(temp_pagelist);
972 			mutex_unlock(&dev->struct_mutex);
973 			atomic_dec(&dev->buf_alloc);
974 			return -ENOMEM;
975 		}
976 		entry->seglist[entry->seg_count++] = dmah;
977 		for (i = 0; i < (1 << page_order); i++) {
978 			DRM_DEBUG("page %d @ 0x%08lx\n",
979 				  dma->page_count + page_count,
980 				  (unsigned long)dmah->vaddr + PAGE_SIZE * i);
981 			temp_pagelist[dma->page_count + page_count++]
982 				= (unsigned long)dmah->vaddr + PAGE_SIZE * i;
983 		}
984 		for (offset = 0;
985 		     offset + size <= total && entry->buf_count < count;
986 		     offset += alignment, ++entry->buf_count) {
987 			buf = &entry->buflist[entry->buf_count];
988 			buf->idx = dma->buf_count + entry->buf_count;
989 			buf->total = alignment;
990 			buf->order = order;
991 			buf->used = 0;
992 			buf->offset = (dma->byte_count + byte_count + offset);
993 			buf->address = ((char *)dmah->vaddr + offset);
994 			buf->bus_address = dmah->busaddr + offset;
995 			buf->next = NULL;
996 			buf->waiting = 0;
997 			buf->pending = 0;
998 			buf->file_priv = NULL;
999 
1000 			buf->dev_priv_size = dev->driver->dev_priv_size;
1001 			buf->dev_private = kzalloc(buf->dev_priv_size,
1002 						GFP_KERNEL);
1003 			if (!buf->dev_private) {
1004 				/* Set count correctly so we free the proper amount. */
1005 				entry->buf_count = count;
1006 				entry->seg_count = count;
1007 				drm_cleanup_buf_error(dev, entry);
1008 				kfree(temp_pagelist);
1009 				mutex_unlock(&dev->struct_mutex);
1010 				atomic_dec(&dev->buf_alloc);
1011 				return -ENOMEM;
1012 			}
1013 
1014 			DRM_DEBUG("buffer %d @ %p\n",
1015 				  entry->buf_count, buf->address);
1016 		}
1017 		byte_count += PAGE_SIZE << page_order;
1018 	}
1019 
1020 	temp_buflist = krealloc(dma->buflist,
1021 				(dma->buf_count + entry->buf_count) *
1022 				sizeof(*dma->buflist), M_DRM, M_WAITOK);
1023 	if (!temp_buflist) {
1024 		/* Free the entry because it isn't valid */
1025 		drm_cleanup_buf_error(dev, entry);
1026 		kfree(temp_pagelist);
1027 		mutex_unlock(&dev->struct_mutex);
1028 		atomic_dec(&dev->buf_alloc);
1029 		return -ENOMEM;
1030 	}
1031 	dma->buflist = temp_buflist;
1032 
1033 	for (i = 0; i < entry->buf_count; i++) {
1034 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1035 	}
1036 
1037 	/* No allocations failed, so now we can replace the original pagelist
1038 	 * with the new one.
1039 	 */
1040 	if (dma->page_count) {
1041 		kfree(dma->pagelist);
1042 	}
1043 	dma->pagelist = temp_pagelist;
1044 
1045 	dma->buf_count += entry->buf_count;
1046 	dma->seg_count += entry->seg_count;
1047 	dma->page_count += entry->seg_count << page_order;
1048 	dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
1049 
1050 	mutex_unlock(&dev->struct_mutex);
1051 
1052 	request->count = entry->buf_count;
1053 	request->size = size;
1054 
1055 	if (request->flags & _DRM_PCI_BUFFER_RO)
1056 		dma->flags = _DRM_DMA_USE_PCI_RO;
1057 
1058 	atomic_dec(&dev->buf_alloc);
1059 	return 0;
1060 
1061 }
1062 EXPORT_SYMBOL(drm_legacy_addbufs_pci);
1063 
1064 static int drm_legacy_addbufs_sg(struct drm_device *dev,
1065 				 struct drm_buf_desc *request)
1066 {
1067 	struct drm_device_dma *dma = dev->dma;
1068 	struct drm_buf_entry *entry;
1069 	struct drm_buf *buf;
1070 	unsigned long offset;
1071 	unsigned long agp_offset;
1072 	int count;
1073 	int order;
1074 	int size;
1075 	int alignment;
1076 	int page_order;
1077 	int total;
1078 	int byte_count;
1079 	int i;
1080 	struct drm_buf **temp_buflist;
1081 
1082 	if (!drm_core_check_feature(dev, DRIVER_SG))
1083 		return -EINVAL;
1084 
1085 	if (!dma)
1086 		return -EINVAL;
1087 
1088 	if (!capable(CAP_SYS_ADMIN))
1089 		return -EPERM;
1090 
1091 	count = request->count;
1092 	order = order_base_2(request->size);
1093 	size = 1 << order;
1094 
1095 	alignment = (request->flags & _DRM_PAGE_ALIGN)
1096 	    ? PAGE_ALIGN(size) : size;
1097 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
1098 	total = PAGE_SIZE << page_order;
1099 
1100 	byte_count = 0;
1101 	agp_offset = request->agp_start;
1102 
1103 	DRM_DEBUG("count:      %d\n", count);
1104 	DRM_DEBUG("order:      %d\n", order);
1105 	DRM_DEBUG("size:       %d\n", size);
1106 	DRM_DEBUG("agp_offset: %lu\n", agp_offset);
1107 	DRM_DEBUG("alignment:  %d\n", alignment);
1108 	DRM_DEBUG("page_order: %d\n", page_order);
1109 	DRM_DEBUG("total:      %d\n", total);
1110 
1111 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1112 		return -EINVAL;
1113 
1114 	spin_lock(&dev->buf_lock);
1115 	if (dev->buf_use) {
1116 		spin_unlock(&dev->buf_lock);
1117 		return -EBUSY;
1118 	}
1119 	atomic_inc(&dev->buf_alloc);
1120 	spin_unlock(&dev->buf_lock);
1121 
1122 	mutex_lock(&dev->struct_mutex);
1123 	entry = &dma->bufs[order];
1124 	if (entry->buf_count) {
1125 		mutex_unlock(&dev->struct_mutex);
1126 		atomic_dec(&dev->buf_alloc);
1127 		return -ENOMEM;	/* May only call once for each order */
1128 	}
1129 
1130 	if (count < 0 || count > 4096) {
1131 		mutex_unlock(&dev->struct_mutex);
1132 		atomic_dec(&dev->buf_alloc);
1133 		return -EINVAL;
1134 	}
1135 
1136 	entry->buflist = kzalloc(count * sizeof(*entry->buflist),
1137 				GFP_KERNEL);
1138 	if (!entry->buflist) {
1139 		mutex_unlock(&dev->struct_mutex);
1140 		atomic_dec(&dev->buf_alloc);
1141 		return -ENOMEM;
1142 	}
1143 
1144 	entry->buf_size = size;
1145 	entry->page_order = page_order;
1146 
1147 	offset = 0;
1148 
1149 	while (entry->buf_count < count) {
1150 		buf = &entry->buflist[entry->buf_count];
1151 		buf->idx = dma->buf_count + entry->buf_count;
1152 		buf->total = alignment;
1153 		buf->order = order;
1154 		buf->used = 0;
1155 
1156 		buf->offset = (dma->byte_count + offset);
1157 		buf->bus_address = agp_offset + offset;
1158 		buf->address = (void *)(agp_offset + offset + dev->sg->vaddr);
1159 		buf->next = NULL;
1160 		buf->waiting = 0;
1161 		buf->pending = 0;
1162 		buf->file_priv = NULL;
1163 
1164 		buf->dev_priv_size = dev->driver->dev_priv_size;
1165 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
1166 		if (!buf->dev_private) {
1167 			/* Set count correctly so we free the proper amount. */
1168 			entry->buf_count = count;
1169 			drm_cleanup_buf_error(dev, entry);
1170 			mutex_unlock(&dev->struct_mutex);
1171 			atomic_dec(&dev->buf_alloc);
1172 			return -ENOMEM;
1173 		}
1174 
1175 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
1176 
1177 		offset += alignment;
1178 		entry->buf_count++;
1179 		byte_count += PAGE_SIZE << page_order;
1180 	}
1181 
1182 	DRM_DEBUG("byte_count: %d\n", byte_count);
1183 
1184 	temp_buflist = krealloc(dma->buflist,
1185 				(dma->buf_count + entry->buf_count) *
1186 				sizeof(*dma->buflist), M_DRM, M_WAITOK);
1187 	if (!temp_buflist) {
1188 		/* Free the entry because it isn't valid */
1189 		drm_cleanup_buf_error(dev, entry);
1190 		mutex_unlock(&dev->struct_mutex);
1191 		atomic_dec(&dev->buf_alloc);
1192 		return -ENOMEM;
1193 	}
1194 	dma->buflist = temp_buflist;
1195 
1196 	for (i = 0; i < entry->buf_count; i++) {
1197 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1198 	}
1199 
1200 	dma->buf_count += entry->buf_count;
1201 	dma->seg_count += entry->seg_count;
1202 	dma->page_count += byte_count >> PAGE_SHIFT;
1203 	dma->byte_count += byte_count;
1204 
1205 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
1206 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
1207 
1208 	mutex_unlock(&dev->struct_mutex);
1209 
1210 	request->count = entry->buf_count;
1211 	request->size = size;
1212 
1213 	dma->flags = _DRM_DMA_USE_SG;
1214 
1215 	atomic_dec(&dev->buf_alloc);
1216 	return 0;
1217 }
1218 
1219 /**
1220  * Add buffers for DMA transfers (ioctl).
1221  *
1222  * \param inode device inode.
1223  * \param file_priv DRM file private.
1224  * \param cmd command.
1225  * \param arg pointer to a struct drm_buf_desc request.
1226  * \return zero on success or a negative number on failure.
1227  *
1228  * According with the memory type specified in drm_buf_desc::flags and the
1229  * build options, it dispatches the call either to addbufs_agp(),
1230  * addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
1231  * PCI memory respectively.
1232  */
1233 int drm_legacy_addbufs(struct drm_device *dev, void *data,
1234 		       struct drm_file *file_priv)
1235 {
1236 	struct drm_buf_desc *request = data;
1237 	int ret;
1238 
1239 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1240 		return -EINVAL;
1241 
1242 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1243 		return -EINVAL;
1244 
1245 #if IS_ENABLED(CONFIG_AGP)
1246 	if (request->flags & _DRM_AGP_BUFFER)
1247 		ret = drm_legacy_addbufs_agp(dev, request);
1248 	else
1249 #endif
1250 	if (request->flags & _DRM_SG_BUFFER)
1251 		ret = drm_legacy_addbufs_sg(dev, request);
1252 	else if (request->flags & _DRM_FB_BUFFER)
1253 		ret = -EINVAL;
1254 	else
1255 		ret = drm_legacy_addbufs_pci(dev, request);
1256 
1257 	return ret;
1258 }
1259 
1260 /**
1261  * Get information about the buffer mappings.
1262  *
1263  * This was originally mean for debugging purposes, or by a sophisticated
1264  * client library to determine how best to use the available buffers (e.g.,
1265  * large buffers can be used for image transfer).
1266  *
1267  * \param inode device inode.
1268  * \param file_priv DRM file private.
1269  * \param cmd command.
1270  * \param arg pointer to a drm_buf_info structure.
1271  * \return zero on success or a negative number on failure.
1272  *
1273  * Increments drm_device::buf_use while holding the drm_device::buf_lock
1274  * lock, preventing of allocating more buffers after this call. Information
1275  * about each requested buffer is then copied into user space.
1276  */
1277 int drm_legacy_infobufs(struct drm_device *dev, void *data,
1278 			struct drm_file *file_priv)
1279 {
1280 	struct drm_device_dma *dma = dev->dma;
1281 	struct drm_buf_info *request = data;
1282 	int i;
1283 	int count;
1284 
1285 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1286 		return -EINVAL;
1287 
1288 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1289 		return -EINVAL;
1290 
1291 	if (!dma)
1292 		return -EINVAL;
1293 
1294 	spin_lock(&dev->buf_lock);
1295 	if (atomic_read(&dev->buf_alloc)) {
1296 		spin_unlock(&dev->buf_lock);
1297 		return -EBUSY;
1298 	}
1299 	++dev->buf_use;		/* Can't allocate more after this call */
1300 	spin_unlock(&dev->buf_lock);
1301 
1302 	for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1303 		if (dma->bufs[i].buf_count)
1304 			++count;
1305 	}
1306 
1307 	DRM_DEBUG("count = %d\n", count);
1308 
1309 	if (request->count >= count) {
1310 		for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1311 			if (dma->bufs[i].buf_count) {
1312 				struct drm_buf_desc __user *to =
1313 				    &request->list[count];
1314 				struct drm_buf_entry *from = &dma->bufs[i];
1315 				if (copy_to_user(&to->count,
1316 						 &from->buf_count,
1317 						 sizeof(from->buf_count)) ||
1318 				    copy_to_user(&to->size,
1319 						 &from->buf_size,
1320 						 sizeof(from->buf_size)) ||
1321 				    copy_to_user(&to->low_mark,
1322 						 &from->low_mark,
1323 						 sizeof(from->low_mark)) ||
1324 				    copy_to_user(&to->high_mark,
1325 						 &from->high_mark,
1326 						 sizeof(from->high_mark)))
1327 					return -EFAULT;
1328 
1329 				DRM_DEBUG("%d %d %d %d %d\n",
1330 					  i,
1331 					  dma->bufs[i].buf_count,
1332 					  dma->bufs[i].buf_size,
1333 					  dma->bufs[i].low_mark,
1334 					  dma->bufs[i].high_mark);
1335 				++count;
1336 			}
1337 		}
1338 	}
1339 	request->count = count;
1340 
1341 	return 0;
1342 }
1343 
1344 /**
1345  * Specifies a low and high water mark for buffer allocation
1346  *
1347  * \param inode device inode.
1348  * \param file_priv DRM file private.
1349  * \param cmd command.
1350  * \param arg a pointer to a drm_buf_desc structure.
1351  * \return zero on success or a negative number on failure.
1352  *
1353  * Verifies that the size order is bounded between the admissible orders and
1354  * updates the respective drm_device_dma::bufs entry low and high water mark.
1355  *
1356  * \note This ioctl is deprecated and mostly never used.
1357  */
1358 int drm_legacy_markbufs(struct drm_device *dev, void *data,
1359 			struct drm_file *file_priv)
1360 {
1361 	struct drm_device_dma *dma = dev->dma;
1362 	struct drm_buf_desc *request = data;
1363 	int order;
1364 	struct drm_buf_entry *entry;
1365 
1366 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1367 		return -EINVAL;
1368 
1369 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1370 		return -EINVAL;
1371 
1372 	if (!dma)
1373 		return -EINVAL;
1374 
1375 	DRM_DEBUG("%d, %d, %d\n",
1376 		  request->size, request->low_mark, request->high_mark);
1377 	order = order_base_2(request->size);
1378 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1379 		return -EINVAL;
1380 	entry = &dma->bufs[order];
1381 
1382 	if (request->low_mark < 0 || request->low_mark > entry->buf_count)
1383 		return -EINVAL;
1384 	if (request->high_mark < 0 || request->high_mark > entry->buf_count)
1385 		return -EINVAL;
1386 
1387 	entry->low_mark = request->low_mark;
1388 	entry->high_mark = request->high_mark;
1389 
1390 	return 0;
1391 }
1392 
1393 /**
1394  * Unreserve the buffers in list, previously reserved using drmDMA.
1395  *
1396  * \param inode device inode.
1397  * \param file_priv DRM file private.
1398  * \param cmd command.
1399  * \param arg pointer to a drm_buf_free structure.
1400  * \return zero on success or a negative number on failure.
1401  *
1402  * Calls free_buffer() for each used buffer.
1403  * This function is primarily used for debugging.
1404  */
1405 int drm_legacy_freebufs(struct drm_device *dev, void *data,
1406 			struct drm_file *file_priv)
1407 {
1408 	struct drm_device_dma *dma = dev->dma;
1409 	struct drm_buf_free *request = data;
1410 	int i;
1411 	int idx;
1412 	struct drm_buf *buf;
1413 
1414 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1415 		return -EINVAL;
1416 
1417 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1418 		return -EINVAL;
1419 
1420 	if (!dma)
1421 		return -EINVAL;
1422 
1423 	DRM_DEBUG("%d\n", request->count);
1424 	for (i = 0; i < request->count; i++) {
1425 		if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
1426 			return -EFAULT;
1427 		if (idx < 0 || idx >= dma->buf_count) {
1428 			DRM_ERROR("Index %d (of %d max)\n",
1429 				  idx, dma->buf_count - 1);
1430 			return -EINVAL;
1431 		}
1432 		buf = dma->buflist[idx];
1433 		if (buf->file_priv != file_priv) {
1434 			DRM_ERROR("Process %d freeing buffer not owned\n",
1435 				  DRM_CURRENTPID);
1436 			return -EINVAL;
1437 		}
1438 		drm_legacy_free_buffer(dev, buf);
1439 	}
1440 
1441 	return 0;
1442 }
1443 
1444 /**
1445  * Maps all of the DMA buffers into client-virtual space (ioctl).
1446  *
1447  * \param inode device inode.
1448  * \param file_priv DRM file private.
1449  * \param cmd command.
1450  * \param arg pointer to a drm_buf_map structure.
1451  * \return zero on success or a negative number on failure.
1452  *
1453  * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information
1454  * about each buffer into user space. For PCI buffers, it calls vm_mmap() with
1455  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
1456  * drm_mmap_dma().
1457  */
1458 int drm_legacy_mapbufs(struct drm_device *dev, void *data,
1459 		       struct drm_file *file_priv)
1460 {
1461 	struct drm_device_dma *dma = dev->dma;
1462 	int retcode = 0;
1463 	const int zero = 0;
1464 	unsigned long virtual;
1465 	vm_offset_t address;
1466 	struct vmspace *vms  = DRM_CURPROC->td_proc->p_vmspace;
1467 	struct drm_buf_map *request = data;
1468 	int i;
1469 
1470 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1471 		return -EINVAL;
1472 
1473 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1474 		return -EINVAL;
1475 
1476 	if (!dma)
1477 		return -EINVAL;
1478 
1479 	spin_lock(&dev->buf_lock);
1480 	if (atomic_read(&dev->buf_alloc)) {
1481 		spin_unlock(&dev->buf_lock);
1482 		return -EBUSY;
1483 	}
1484 	dev->buf_use++;		/* Can't allocate more after this call */
1485 	spin_unlock(&dev->buf_lock);
1486 
1487 	if (request->count >= dma->buf_count) {
1488 		if ((dev->agp && (dma->flags & _DRM_DMA_USE_AGP))
1489 		    || (drm_core_check_feature(dev, DRIVER_SG)
1490 			&& (dma->flags & _DRM_DMA_USE_SG))) {
1491 			struct drm_local_map *map = dev->agp_buffer_map;
1492 			unsigned long token = dev->agp_buffer_token;
1493 
1494 			if (!map) {
1495 				retcode = -EINVAL;
1496 				goto done;
1497 			}
1498 			virtual = vm_mmap(&vms->vm_map, 0, map->size,
1499 					  PROT_READ | PROT_WRITE,
1500 					  VM_PROT_ALL,
1501 					  MAP_SHARED,
1502 					  SLIST_FIRST(&dev->devnode->si_hlist),
1503 					  token);
1504 		} else {
1505 			virtual = vm_mmap(&vms->vm_map, 0, dma->byte_count,
1506 					  PROT_READ | PROT_WRITE,
1507 					  VM_PROT_ALL,
1508 					  MAP_SHARED,
1509 					  SLIST_FIRST(&dev->devnode->si_hlist),
1510 					  0);
1511 		}
1512 		if (virtual > -1024UL) {
1513 			/* Real error */
1514 			retcode = (signed long)virtual;
1515 			goto done;
1516 		}
1517 		request->virtual = (void __user *)virtual;
1518 
1519 		for (i = 0; i < dma->buf_count; i++) {
1520 			if (copy_to_user(&request->list[i].idx,
1521 					 &dma->buflist[i]->idx,
1522 					 sizeof(request->list[0].idx))) {
1523 				retcode = -EFAULT;
1524 				goto done;
1525 			}
1526 			if (copy_to_user(&request->list[i].total,
1527 					 &dma->buflist[i]->total,
1528 					 sizeof(request->list[0].total))) {
1529 				retcode = -EFAULT;
1530 				goto done;
1531 			}
1532 			if (copy_to_user(&request->list[i].used,
1533 					 &zero, sizeof(zero))) {
1534 				retcode = -EFAULT;
1535 				goto done;
1536 			}
1537 			address = virtual + dma->buflist[i]->offset;	/* *** */
1538 			if (copy_to_user(&request->list[i].address,
1539 					 &address, sizeof(address))) {
1540 				retcode = -EFAULT;
1541 				goto done;
1542 			}
1543 		}
1544 	}
1545       done:
1546 	request->count = dma->buf_count;
1547 	DRM_DEBUG("%d buffers, retcode = %d\n", request->count, retcode);
1548 
1549 	return retcode;
1550 }
1551 
1552 int drm_legacy_dma_ioctl(struct drm_device *dev, void *data,
1553 		  struct drm_file *file_priv)
1554 {
1555 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1556 		return -EINVAL;
1557 
1558 	if (dev->driver->dma_ioctl)
1559 		return dev->driver->dma_ioctl(dev, data, file_priv);
1560 	else
1561 		return -EINVAL;
1562 }
1563 
1564 struct drm_local_map *drm_legacy_getsarea(struct drm_device *dev)
1565 {
1566 	struct drm_map_list *entry;
1567 
1568 	list_for_each_entry(entry, &dev->maplist, head) {
1569 		if (entry->map && entry->map->type == _DRM_SHM &&
1570 		    (entry->map->flags & _DRM_CONTAINS_LOCK)) {
1571 			return entry->map;
1572 		}
1573 	}
1574 	return NULL;
1575 }
1576 EXPORT_SYMBOL(drm_legacy_getsarea);
1577