xref: /openbmc/linux/drivers/gpu/drm/drm_bufs.c (revision 5bd8e16d)
1 /**
2  * \file drm_bufs.c
3  * Generic buffer template
4  *
5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
6  * \author Gareth Hughes <gareth@valinux.com>
7  */
8 
9 /*
10  * Created: Thu Nov 23 03:10:50 2000 by gareth@valinux.com
11  *
12  * Copyright 1999, 2000 Precision Insight, Inc., Cedar Park, Texas.
13  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14  * All Rights Reserved.
15  *
16  * Permission is hereby granted, free of charge, to any person obtaining a
17  * copy of this software and associated documentation files (the "Software"),
18  * to deal in the Software without restriction, including without limitation
19  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
20  * and/or sell copies of the Software, and to permit persons to whom the
21  * Software is furnished to do so, subject to the following conditions:
22  *
23  * The above copyright notice and this permission notice (including the next
24  * paragraph) shall be included in all copies or substantial portions of the
25  * Software.
26  *
27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
28  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
29  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
30  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
31  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
32  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
33  * OTHER DEALINGS IN THE SOFTWARE.
34  */
35 
36 #include <linux/vmalloc.h>
37 #include <linux/slab.h>
38 #include <linux/log2.h>
39 #include <linux/export.h>
40 #include <asm/shmparam.h>
41 #include <drm/drmP.h>
42 
43 static struct drm_map_list *drm_find_matching_map(struct drm_device *dev,
44 						  struct drm_local_map *map)
45 {
46 	struct drm_map_list *entry;
47 	list_for_each_entry(entry, &dev->maplist, head) {
48 		/*
49 		 * Because the kernel-userspace ABI is fixed at a 32-bit offset
50 		 * while PCI resources may live above that, we only compare the
51 		 * lower 32 bits of the map offset for maps of type
52 		 * _DRM_FRAMEBUFFER or _DRM_REGISTERS.
53 		 * It is assumed that if a driver have more than one resource
54 		 * of each type, the lower 32 bits are different.
55 		 */
56 		if (!entry->map ||
57 		    map->type != entry->map->type ||
58 		    entry->master != dev->primary->master)
59 			continue;
60 		switch (map->type) {
61 		case _DRM_SHM:
62 			if (map->flags != _DRM_CONTAINS_LOCK)
63 				break;
64 			return entry;
65 		case _DRM_REGISTERS:
66 		case _DRM_FRAME_BUFFER:
67 			if ((entry->map->offset & 0xffffffff) ==
68 			    (map->offset & 0xffffffff))
69 				return entry;
70 		default: /* Make gcc happy */
71 			;
72 		}
73 		if (entry->map->offset == map->offset)
74 			return entry;
75 	}
76 
77 	return NULL;
78 }
79 
80 static int drm_map_handle(struct drm_device *dev, struct drm_hash_item *hash,
81 			  unsigned long user_token, int hashed_handle, int shm)
82 {
83 	int use_hashed_handle, shift;
84 	unsigned long add;
85 
86 #if (BITS_PER_LONG == 64)
87 	use_hashed_handle = ((user_token & 0xFFFFFFFF00000000UL) || hashed_handle);
88 #elif (BITS_PER_LONG == 32)
89 	use_hashed_handle = hashed_handle;
90 #else
91 #error Unsupported long size. Neither 64 nor 32 bits.
92 #endif
93 
94 	if (!use_hashed_handle) {
95 		int ret;
96 		hash->key = user_token >> PAGE_SHIFT;
97 		ret = drm_ht_insert_item(&dev->map_hash, hash);
98 		if (ret != -EINVAL)
99 			return ret;
100 	}
101 
102 	shift = 0;
103 	add = DRM_MAP_HASH_OFFSET >> PAGE_SHIFT;
104 	if (shm && (SHMLBA > PAGE_SIZE)) {
105 		int bits = ilog2(SHMLBA >> PAGE_SHIFT) + 1;
106 
107 		/* For shared memory, we have to preserve the SHMLBA
108 		 * bits of the eventual vma->vm_pgoff value during
109 		 * mmap().  Otherwise we run into cache aliasing problems
110 		 * on some platforms.  On these platforms, the pgoff of
111 		 * a mmap() request is used to pick a suitable virtual
112 		 * address for the mmap() region such that it will not
113 		 * cause cache aliasing problems.
114 		 *
115 		 * Therefore, make sure the SHMLBA relevant bits of the
116 		 * hash value we use are equal to those in the original
117 		 * kernel virtual address.
118 		 */
119 		shift = bits;
120 		add |= ((user_token >> PAGE_SHIFT) & ((1UL << bits) - 1UL));
121 	}
122 
123 	return drm_ht_just_insert_please(&dev->map_hash, hash,
124 					 user_token, 32 - PAGE_SHIFT - 3,
125 					 shift, add);
126 }
127 
128 /**
129  * Core function to create a range of memory available for mapping by a
130  * non-root process.
131  *
132  * Adjusts the memory offset to its absolute value according to the mapping
133  * type.  Adds the map to the map list drm_device::maplist. Adds MTRR's where
134  * applicable and if supported by the kernel.
135  */
136 static int drm_addmap_core(struct drm_device * dev, resource_size_t offset,
137 			   unsigned int size, enum drm_map_type type,
138 			   enum drm_map_flags flags,
139 			   struct drm_map_list ** maplist)
140 {
141 	struct drm_local_map *map;
142 	struct drm_map_list *list;
143 	drm_dma_handle_t *dmah;
144 	unsigned long user_token;
145 	int ret;
146 
147 	map = kmalloc(sizeof(*map), GFP_KERNEL);
148 	if (!map)
149 		return -ENOMEM;
150 
151 	map->offset = offset;
152 	map->size = size;
153 	map->flags = flags;
154 	map->type = type;
155 
156 	/* Only allow shared memory to be removable since we only keep enough
157 	 * book keeping information about shared memory to allow for removal
158 	 * when processes fork.
159 	 */
160 	if ((map->flags & _DRM_REMOVABLE) && map->type != _DRM_SHM) {
161 		kfree(map);
162 		return -EINVAL;
163 	}
164 	DRM_DEBUG("offset = 0x%08llx, size = 0x%08lx, type = %d\n",
165 		  (unsigned long long)map->offset, map->size, map->type);
166 
167 	/* page-align _DRM_SHM maps. They are allocated here so there is no security
168 	 * hole created by that and it works around various broken drivers that use
169 	 * a non-aligned quantity to map the SAREA. --BenH
170 	 */
171 	if (map->type == _DRM_SHM)
172 		map->size = PAGE_ALIGN(map->size);
173 
174 	if ((map->offset & (~(resource_size_t)PAGE_MASK)) || (map->size & (~PAGE_MASK))) {
175 		kfree(map);
176 		return -EINVAL;
177 	}
178 	map->mtrr = -1;
179 	map->handle = NULL;
180 
181 	switch (map->type) {
182 	case _DRM_REGISTERS:
183 	case _DRM_FRAME_BUFFER:
184 #if !defined(__sparc__) && !defined(__alpha__) && !defined(__ia64__) && !defined(__powerpc64__) && !defined(__x86_64__) && !defined(__arm__)
185 		if (map->offset + (map->size-1) < map->offset ||
186 		    map->offset < virt_to_phys(high_memory)) {
187 			kfree(map);
188 			return -EINVAL;
189 		}
190 #endif
191 		/* Some drivers preinitialize some maps, without the X Server
192 		 * needing to be aware of it.  Therefore, we just return success
193 		 * when the server tries to create a duplicate map.
194 		 */
195 		list = drm_find_matching_map(dev, map);
196 		if (list != NULL) {
197 			if (list->map->size != map->size) {
198 				DRM_DEBUG("Matching maps of type %d with "
199 					  "mismatched sizes, (%ld vs %ld)\n",
200 					  map->type, map->size,
201 					  list->map->size);
202 				list->map->size = map->size;
203 			}
204 
205 			kfree(map);
206 			*maplist = list;
207 			return 0;
208 		}
209 
210 		if (map->type == _DRM_FRAME_BUFFER ||
211 		    (map->flags & _DRM_WRITE_COMBINING)) {
212 			map->mtrr =
213 				arch_phys_wc_add(map->offset, map->size);
214 		}
215 		if (map->type == _DRM_REGISTERS) {
216 			if (map->flags & _DRM_WRITE_COMBINING)
217 				map->handle = ioremap_wc(map->offset,
218 							 map->size);
219 			else
220 				map->handle = ioremap(map->offset, map->size);
221 			if (!map->handle) {
222 				kfree(map);
223 				return -ENOMEM;
224 			}
225 		}
226 
227 		break;
228 	case _DRM_SHM:
229 		list = drm_find_matching_map(dev, map);
230 		if (list != NULL) {
231 			if(list->map->size != map->size) {
232 				DRM_DEBUG("Matching maps of type %d with "
233 					  "mismatched sizes, (%ld vs %ld)\n",
234 					  map->type, map->size, list->map->size);
235 				list->map->size = map->size;
236 			}
237 
238 			kfree(map);
239 			*maplist = list;
240 			return 0;
241 		}
242 		map->handle = vmalloc_user(map->size);
243 		DRM_DEBUG("%lu %d %p\n",
244 			  map->size, order_base_2(map->size), map->handle);
245 		if (!map->handle) {
246 			kfree(map);
247 			return -ENOMEM;
248 		}
249 		map->offset = (unsigned long)map->handle;
250 		if (map->flags & _DRM_CONTAINS_LOCK) {
251 			/* Prevent a 2nd X Server from creating a 2nd lock */
252 			if (dev->primary->master->lock.hw_lock != NULL) {
253 				vfree(map->handle);
254 				kfree(map);
255 				return -EBUSY;
256 			}
257 			dev->sigdata.lock = dev->primary->master->lock.hw_lock = map->handle;	/* Pointer to lock */
258 		}
259 		break;
260 	case _DRM_AGP: {
261 		struct drm_agp_mem *entry;
262 		int valid = 0;
263 
264 		if (!drm_core_has_AGP(dev)) {
265 			kfree(map);
266 			return -EINVAL;
267 		}
268 #ifdef __alpha__
269 		map->offset += dev->hose->mem_space->start;
270 #endif
271 		/* In some cases (i810 driver), user space may have already
272 		 * added the AGP base itself, because dev->agp->base previously
273 		 * only got set during AGP enable.  So, only add the base
274 		 * address if the map's offset isn't already within the
275 		 * aperture.
276 		 */
277 		if (map->offset < dev->agp->base ||
278 		    map->offset > dev->agp->base +
279 		    dev->agp->agp_info.aper_size * 1024 * 1024 - 1) {
280 			map->offset += dev->agp->base;
281 		}
282 		map->mtrr = dev->agp->agp_mtrr;	/* for getmap */
283 
284 		/* This assumes the DRM is in total control of AGP space.
285 		 * It's not always the case as AGP can be in the control
286 		 * of user space (i.e. i810 driver). So this loop will get
287 		 * skipped and we double check that dev->agp->memory is
288 		 * actually set as well as being invalid before EPERM'ing
289 		 */
290 		list_for_each_entry(entry, &dev->agp->memory, head) {
291 			if ((map->offset >= entry->bound) &&
292 			    (map->offset + map->size <= entry->bound + entry->pages * PAGE_SIZE)) {
293 				valid = 1;
294 				break;
295 			}
296 		}
297 		if (!list_empty(&dev->agp->memory) && !valid) {
298 			kfree(map);
299 			return -EPERM;
300 		}
301 		DRM_DEBUG("AGP offset = 0x%08llx, size = 0x%08lx\n",
302 			  (unsigned long long)map->offset, map->size);
303 
304 		break;
305 	}
306 	case _DRM_GEM:
307 		DRM_ERROR("tried to addmap GEM object\n");
308 		break;
309 	case _DRM_SCATTER_GATHER:
310 		if (!dev->sg) {
311 			kfree(map);
312 			return -EINVAL;
313 		}
314 		map->offset += (unsigned long)dev->sg->virtual;
315 		break;
316 	case _DRM_CONSISTENT:
317 		/* dma_addr_t is 64bit on i386 with CONFIG_HIGHMEM64G,
318 		 * As we're limiting the address to 2^32-1 (or less),
319 		 * casting it down to 32 bits is no problem, but we
320 		 * need to point to a 64bit variable first. */
321 		dmah = drm_pci_alloc(dev, map->size, map->size);
322 		if (!dmah) {
323 			kfree(map);
324 			return -ENOMEM;
325 		}
326 		map->handle = dmah->vaddr;
327 		map->offset = (unsigned long)dmah->busaddr;
328 		kfree(dmah);
329 		break;
330 	default:
331 		kfree(map);
332 		return -EINVAL;
333 	}
334 
335 	list = kzalloc(sizeof(*list), GFP_KERNEL);
336 	if (!list) {
337 		if (map->type == _DRM_REGISTERS)
338 			iounmap(map->handle);
339 		kfree(map);
340 		return -EINVAL;
341 	}
342 	list->map = map;
343 
344 	mutex_lock(&dev->struct_mutex);
345 	list_add(&list->head, &dev->maplist);
346 
347 	/* Assign a 32-bit handle */
348 	/* We do it here so that dev->struct_mutex protects the increment */
349 	user_token = (map->type == _DRM_SHM) ? (unsigned long)map->handle :
350 		map->offset;
351 	ret = drm_map_handle(dev, &list->hash, user_token, 0,
352 			     (map->type == _DRM_SHM));
353 	if (ret) {
354 		if (map->type == _DRM_REGISTERS)
355 			iounmap(map->handle);
356 		kfree(map);
357 		kfree(list);
358 		mutex_unlock(&dev->struct_mutex);
359 		return ret;
360 	}
361 
362 	list->user_token = list->hash.key << PAGE_SHIFT;
363 	mutex_unlock(&dev->struct_mutex);
364 
365 	if (!(map->flags & _DRM_DRIVER))
366 		list->master = dev->primary->master;
367 	*maplist = list;
368 	return 0;
369 	}
370 
371 int drm_addmap(struct drm_device * dev, resource_size_t offset,
372 	       unsigned int size, enum drm_map_type type,
373 	       enum drm_map_flags flags, struct drm_local_map ** map_ptr)
374 {
375 	struct drm_map_list *list;
376 	int rc;
377 
378 	rc = drm_addmap_core(dev, offset, size, type, flags, &list);
379 	if (!rc)
380 		*map_ptr = list->map;
381 	return rc;
382 }
383 
384 EXPORT_SYMBOL(drm_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_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 	err = drm_addmap_core(dev, map->offset, map->size, map->type,
408 			      map->flags, &maplist);
409 
410 	if (err)
411 		return err;
412 
413 	/* avoid a warning on 64-bit, this casting isn't very nice, but the API is set so too late */
414 	map->handle = (void *)(unsigned long)maplist->user_token;
415 
416 	/*
417 	 * It appears that there are no users of this value whatsoever --
418 	 * drmAddMap just discards it.  Let's not encourage its use.
419 	 * (Keeping drm_addmap_core's returned mtrr value would be wrong --
420 	 *  it's not a real mtrr index anymore.)
421 	 */
422 	map->mtrr = -1;
423 
424 	return 0;
425 }
426 
427 /**
428  * Remove a map private from list and deallocate resources if the mapping
429  * isn't in use.
430  *
431  * Searches the map on drm_device::maplist, removes it from the list, see if
432  * its being used, and free any associate resource (such as MTRR's) if it's not
433  * being on use.
434  *
435  * \sa drm_addmap
436  */
437 int drm_rmmap_locked(struct drm_device *dev, struct drm_local_map *map)
438 {
439 	struct drm_map_list *r_list = NULL, *list_t;
440 	drm_dma_handle_t dmah;
441 	int found = 0;
442 	struct drm_master *master;
443 
444 	/* Find the list entry for the map and remove it */
445 	list_for_each_entry_safe(r_list, list_t, &dev->maplist, head) {
446 		if (r_list->map == map) {
447 			master = r_list->master;
448 			list_del(&r_list->head);
449 			drm_ht_remove_key(&dev->map_hash,
450 					  r_list->user_token >> PAGE_SHIFT);
451 			kfree(r_list);
452 			found = 1;
453 			break;
454 		}
455 	}
456 
457 	if (!found)
458 		return -EINVAL;
459 
460 	switch (map->type) {
461 	case _DRM_REGISTERS:
462 		iounmap(map->handle);
463 		/* FALLTHROUGH */
464 	case _DRM_FRAME_BUFFER:
465 		arch_phys_wc_del(map->mtrr);
466 		break;
467 	case _DRM_SHM:
468 		vfree(map->handle);
469 		if (master) {
470 			if (dev->sigdata.lock == master->lock.hw_lock)
471 				dev->sigdata.lock = NULL;
472 			master->lock.hw_lock = NULL;   /* SHM removed */
473 			master->lock.file_priv = NULL;
474 			wake_up_interruptible_all(&master->lock.lock_queue);
475 		}
476 		break;
477 	case _DRM_AGP:
478 	case _DRM_SCATTER_GATHER:
479 		break;
480 	case _DRM_CONSISTENT:
481 		dmah.vaddr = map->handle;
482 		dmah.busaddr = map->offset;
483 		dmah.size = map->size;
484 		__drm_pci_free(dev, &dmah);
485 		break;
486 	case _DRM_GEM:
487 		DRM_ERROR("tried to rmmap GEM object\n");
488 		break;
489 	}
490 	kfree(map);
491 
492 	return 0;
493 }
494 EXPORT_SYMBOL(drm_rmmap_locked);
495 
496 int drm_rmmap(struct drm_device *dev, struct drm_local_map *map)
497 {
498 	int ret;
499 
500 	mutex_lock(&dev->struct_mutex);
501 	ret = drm_rmmap_locked(dev, map);
502 	mutex_unlock(&dev->struct_mutex);
503 
504 	return ret;
505 }
506 EXPORT_SYMBOL(drm_rmmap);
507 
508 /* The rmmap ioctl appears to be unnecessary.  All mappings are torn down on
509  * the last close of the device, and this is necessary for cleanup when things
510  * exit uncleanly.  Therefore, having userland manually remove mappings seems
511  * like a pointless exercise since they're going away anyway.
512  *
513  * One use case might be after addmap is allowed for normal users for SHM and
514  * gets used by drivers that the server doesn't need to care about.  This seems
515  * unlikely.
516  *
517  * \param inode device inode.
518  * \param file_priv DRM file private.
519  * \param cmd command.
520  * \param arg pointer to a struct drm_map structure.
521  * \return zero on success or a negative value on error.
522  */
523 int drm_rmmap_ioctl(struct drm_device *dev, void *data,
524 		    struct drm_file *file_priv)
525 {
526 	struct drm_map *request = data;
527 	struct drm_local_map *map = NULL;
528 	struct drm_map_list *r_list;
529 	int ret;
530 
531 	mutex_lock(&dev->struct_mutex);
532 	list_for_each_entry(r_list, &dev->maplist, head) {
533 		if (r_list->map &&
534 		    r_list->user_token == (unsigned long)request->handle &&
535 		    r_list->map->flags & _DRM_REMOVABLE) {
536 			map = r_list->map;
537 			break;
538 		}
539 	}
540 
541 	/* List has wrapped around to the head pointer, or its empty we didn't
542 	 * find anything.
543 	 */
544 	if (list_empty(&dev->maplist) || !map) {
545 		mutex_unlock(&dev->struct_mutex);
546 		return -EINVAL;
547 	}
548 
549 	/* Register and framebuffer maps are permanent */
550 	if ((map->type == _DRM_REGISTERS) || (map->type == _DRM_FRAME_BUFFER)) {
551 		mutex_unlock(&dev->struct_mutex);
552 		return 0;
553 	}
554 
555 	ret = drm_rmmap_locked(dev, map);
556 
557 	mutex_unlock(&dev->struct_mutex);
558 
559 	return ret;
560 }
561 
562 /**
563  * Cleanup after an error on one of the addbufs() functions.
564  *
565  * \param dev DRM device.
566  * \param entry buffer entry where the error occurred.
567  *
568  * Frees any pages and buffers associated with the given entry.
569  */
570 static void drm_cleanup_buf_error(struct drm_device * dev,
571 				  struct drm_buf_entry * entry)
572 {
573 	int i;
574 
575 	if (entry->seg_count) {
576 		for (i = 0; i < entry->seg_count; i++) {
577 			if (entry->seglist[i]) {
578 				drm_pci_free(dev, entry->seglist[i]);
579 			}
580 		}
581 		kfree(entry->seglist);
582 
583 		entry->seg_count = 0;
584 	}
585 
586 	if (entry->buf_count) {
587 		for (i = 0; i < entry->buf_count; i++) {
588 			kfree(entry->buflist[i].dev_private);
589 		}
590 		kfree(entry->buflist);
591 
592 		entry->buf_count = 0;
593 	}
594 }
595 
596 #if __OS_HAS_AGP
597 /**
598  * Add AGP buffers for DMA transfers.
599  *
600  * \param dev struct drm_device to which the buffers are to be added.
601  * \param request pointer to a struct drm_buf_desc describing the request.
602  * \return zero on success or a negative number on failure.
603  *
604  * After some sanity checks creates a drm_buf structure for each buffer and
605  * reallocates the buffer list of the same size order to accommodate the new
606  * buffers.
607  */
608 int drm_addbufs_agp(struct drm_device * dev, struct drm_buf_desc * request)
609 {
610 	struct drm_device_dma *dma = dev->dma;
611 	struct drm_buf_entry *entry;
612 	struct drm_agp_mem *agp_entry;
613 	struct drm_buf *buf;
614 	unsigned long offset;
615 	unsigned long agp_offset;
616 	int count;
617 	int order;
618 	int size;
619 	int alignment;
620 	int page_order;
621 	int total;
622 	int byte_count;
623 	int i, valid;
624 	struct drm_buf **temp_buflist;
625 
626 	if (!dma)
627 		return -EINVAL;
628 
629 	count = request->count;
630 	order = order_base_2(request->size);
631 	size = 1 << order;
632 
633 	alignment = (request->flags & _DRM_PAGE_ALIGN)
634 	    ? PAGE_ALIGN(size) : size;
635 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
636 	total = PAGE_SIZE << page_order;
637 
638 	byte_count = 0;
639 	agp_offset = dev->agp->base + request->agp_start;
640 
641 	DRM_DEBUG("count:      %d\n", count);
642 	DRM_DEBUG("order:      %d\n", order);
643 	DRM_DEBUG("size:       %d\n", size);
644 	DRM_DEBUG("agp_offset: %lx\n", agp_offset);
645 	DRM_DEBUG("alignment:  %d\n", alignment);
646 	DRM_DEBUG("page_order: %d\n", page_order);
647 	DRM_DEBUG("total:      %d\n", total);
648 
649 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
650 		return -EINVAL;
651 
652 	/* Make sure buffers are located in AGP memory that we own */
653 	valid = 0;
654 	list_for_each_entry(agp_entry, &dev->agp->memory, head) {
655 		if ((agp_offset >= agp_entry->bound) &&
656 		    (agp_offset + total * count <= agp_entry->bound + agp_entry->pages * PAGE_SIZE)) {
657 			valid = 1;
658 			break;
659 		}
660 	}
661 	if (!list_empty(&dev->agp->memory) && !valid) {
662 		DRM_DEBUG("zone invalid\n");
663 		return -EINVAL;
664 	}
665 	spin_lock(&dev->count_lock);
666 	if (dev->buf_use) {
667 		spin_unlock(&dev->count_lock);
668 		return -EBUSY;
669 	}
670 	atomic_inc(&dev->buf_alloc);
671 	spin_unlock(&dev->count_lock);
672 
673 	mutex_lock(&dev->struct_mutex);
674 	entry = &dma->bufs[order];
675 	if (entry->buf_count) {
676 		mutex_unlock(&dev->struct_mutex);
677 		atomic_dec(&dev->buf_alloc);
678 		return -ENOMEM;	/* May only call once for each order */
679 	}
680 
681 	if (count < 0 || count > 4096) {
682 		mutex_unlock(&dev->struct_mutex);
683 		atomic_dec(&dev->buf_alloc);
684 		return -EINVAL;
685 	}
686 
687 	entry->buflist = kzalloc(count * sizeof(*entry->buflist), GFP_KERNEL);
688 	if (!entry->buflist) {
689 		mutex_unlock(&dev->struct_mutex);
690 		atomic_dec(&dev->buf_alloc);
691 		return -ENOMEM;
692 	}
693 
694 	entry->buf_size = size;
695 	entry->page_order = page_order;
696 
697 	offset = 0;
698 
699 	while (entry->buf_count < count) {
700 		buf = &entry->buflist[entry->buf_count];
701 		buf->idx = dma->buf_count + entry->buf_count;
702 		buf->total = alignment;
703 		buf->order = order;
704 		buf->used = 0;
705 
706 		buf->offset = (dma->byte_count + offset);
707 		buf->bus_address = agp_offset + offset;
708 		buf->address = (void *)(agp_offset + offset);
709 		buf->next = NULL;
710 		buf->waiting = 0;
711 		buf->pending = 0;
712 		buf->file_priv = NULL;
713 
714 		buf->dev_priv_size = dev->driver->dev_priv_size;
715 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
716 		if (!buf->dev_private) {
717 			/* Set count correctly so we free the proper amount. */
718 			entry->buf_count = count;
719 			drm_cleanup_buf_error(dev, entry);
720 			mutex_unlock(&dev->struct_mutex);
721 			atomic_dec(&dev->buf_alloc);
722 			return -ENOMEM;
723 		}
724 
725 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
726 
727 		offset += alignment;
728 		entry->buf_count++;
729 		byte_count += PAGE_SIZE << page_order;
730 	}
731 
732 	DRM_DEBUG("byte_count: %d\n", byte_count);
733 
734 	temp_buflist = krealloc(dma->buflist,
735 				(dma->buf_count + entry->buf_count) *
736 				sizeof(*dma->buflist), GFP_KERNEL);
737 	if (!temp_buflist) {
738 		/* Free the entry because it isn't valid */
739 		drm_cleanup_buf_error(dev, entry);
740 		mutex_unlock(&dev->struct_mutex);
741 		atomic_dec(&dev->buf_alloc);
742 		return -ENOMEM;
743 	}
744 	dma->buflist = temp_buflist;
745 
746 	for (i = 0; i < entry->buf_count; i++) {
747 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
748 	}
749 
750 	dma->buf_count += entry->buf_count;
751 	dma->seg_count += entry->seg_count;
752 	dma->page_count += byte_count >> PAGE_SHIFT;
753 	dma->byte_count += byte_count;
754 
755 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
756 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
757 
758 	mutex_unlock(&dev->struct_mutex);
759 
760 	request->count = entry->buf_count;
761 	request->size = size;
762 
763 	dma->flags = _DRM_DMA_USE_AGP;
764 
765 	atomic_dec(&dev->buf_alloc);
766 	return 0;
767 }
768 EXPORT_SYMBOL(drm_addbufs_agp);
769 #endif				/* __OS_HAS_AGP */
770 
771 int drm_addbufs_pci(struct drm_device * dev, struct drm_buf_desc * request)
772 {
773 	struct drm_device_dma *dma = dev->dma;
774 	int count;
775 	int order;
776 	int size;
777 	int total;
778 	int page_order;
779 	struct drm_buf_entry *entry;
780 	drm_dma_handle_t *dmah;
781 	struct drm_buf *buf;
782 	int alignment;
783 	unsigned long offset;
784 	int i;
785 	int byte_count;
786 	int page_count;
787 	unsigned long *temp_pagelist;
788 	struct drm_buf **temp_buflist;
789 
790 	if (!drm_core_check_feature(dev, DRIVER_PCI_DMA))
791 		return -EINVAL;
792 
793 	if (!dma)
794 		return -EINVAL;
795 
796 	if (!capable(CAP_SYS_ADMIN))
797 		return -EPERM;
798 
799 	count = request->count;
800 	order = order_base_2(request->size);
801 	size = 1 << order;
802 
803 	DRM_DEBUG("count=%d, size=%d (%d), order=%d\n",
804 		  request->count, request->size, size, order);
805 
806 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
807 		return -EINVAL;
808 
809 	alignment = (request->flags & _DRM_PAGE_ALIGN)
810 	    ? PAGE_ALIGN(size) : size;
811 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
812 	total = PAGE_SIZE << page_order;
813 
814 	spin_lock(&dev->count_lock);
815 	if (dev->buf_use) {
816 		spin_unlock(&dev->count_lock);
817 		return -EBUSY;
818 	}
819 	atomic_inc(&dev->buf_alloc);
820 	spin_unlock(&dev->count_lock);
821 
822 	mutex_lock(&dev->struct_mutex);
823 	entry = &dma->bufs[order];
824 	if (entry->buf_count) {
825 		mutex_unlock(&dev->struct_mutex);
826 		atomic_dec(&dev->buf_alloc);
827 		return -ENOMEM;	/* May only call once for each order */
828 	}
829 
830 	if (count < 0 || count > 4096) {
831 		mutex_unlock(&dev->struct_mutex);
832 		atomic_dec(&dev->buf_alloc);
833 		return -EINVAL;
834 	}
835 
836 	entry->buflist = kzalloc(count * sizeof(*entry->buflist), GFP_KERNEL);
837 	if (!entry->buflist) {
838 		mutex_unlock(&dev->struct_mutex);
839 		atomic_dec(&dev->buf_alloc);
840 		return -ENOMEM;
841 	}
842 
843 	entry->seglist = kzalloc(count * sizeof(*entry->seglist), GFP_KERNEL);
844 	if (!entry->seglist) {
845 		kfree(entry->buflist);
846 		mutex_unlock(&dev->struct_mutex);
847 		atomic_dec(&dev->buf_alloc);
848 		return -ENOMEM;
849 	}
850 
851 	/* Keep the original pagelist until we know all the allocations
852 	 * have succeeded
853 	 */
854 	temp_pagelist = kmalloc((dma->page_count + (count << page_order)) *
855 			       sizeof(*dma->pagelist), GFP_KERNEL);
856 	if (!temp_pagelist) {
857 		kfree(entry->buflist);
858 		kfree(entry->seglist);
859 		mutex_unlock(&dev->struct_mutex);
860 		atomic_dec(&dev->buf_alloc);
861 		return -ENOMEM;
862 	}
863 	memcpy(temp_pagelist,
864 	       dma->pagelist, dma->page_count * sizeof(*dma->pagelist));
865 	DRM_DEBUG("pagelist: %d entries\n",
866 		  dma->page_count + (count << page_order));
867 
868 	entry->buf_size = size;
869 	entry->page_order = page_order;
870 	byte_count = 0;
871 	page_count = 0;
872 
873 	while (entry->buf_count < count) {
874 
875 		dmah = drm_pci_alloc(dev, PAGE_SIZE << page_order, 0x1000);
876 
877 		if (!dmah) {
878 			/* Set count correctly so we free the proper amount. */
879 			entry->buf_count = count;
880 			entry->seg_count = count;
881 			drm_cleanup_buf_error(dev, entry);
882 			kfree(temp_pagelist);
883 			mutex_unlock(&dev->struct_mutex);
884 			atomic_dec(&dev->buf_alloc);
885 			return -ENOMEM;
886 		}
887 		entry->seglist[entry->seg_count++] = dmah;
888 		for (i = 0; i < (1 << page_order); i++) {
889 			DRM_DEBUG("page %d @ 0x%08lx\n",
890 				  dma->page_count + page_count,
891 				  (unsigned long)dmah->vaddr + PAGE_SIZE * i);
892 			temp_pagelist[dma->page_count + page_count++]
893 				= (unsigned long)dmah->vaddr + PAGE_SIZE * i;
894 		}
895 		for (offset = 0;
896 		     offset + size <= total && entry->buf_count < count;
897 		     offset += alignment, ++entry->buf_count) {
898 			buf = &entry->buflist[entry->buf_count];
899 			buf->idx = dma->buf_count + entry->buf_count;
900 			buf->total = alignment;
901 			buf->order = order;
902 			buf->used = 0;
903 			buf->offset = (dma->byte_count + byte_count + offset);
904 			buf->address = (void *)(dmah->vaddr + offset);
905 			buf->bus_address = dmah->busaddr + offset;
906 			buf->next = NULL;
907 			buf->waiting = 0;
908 			buf->pending = 0;
909 			buf->file_priv = NULL;
910 
911 			buf->dev_priv_size = dev->driver->dev_priv_size;
912 			buf->dev_private = kzalloc(buf->dev_priv_size,
913 						GFP_KERNEL);
914 			if (!buf->dev_private) {
915 				/* Set count correctly so we free the proper amount. */
916 				entry->buf_count = count;
917 				entry->seg_count = count;
918 				drm_cleanup_buf_error(dev, entry);
919 				kfree(temp_pagelist);
920 				mutex_unlock(&dev->struct_mutex);
921 				atomic_dec(&dev->buf_alloc);
922 				return -ENOMEM;
923 			}
924 
925 			DRM_DEBUG("buffer %d @ %p\n",
926 				  entry->buf_count, buf->address);
927 		}
928 		byte_count += PAGE_SIZE << page_order;
929 	}
930 
931 	temp_buflist = krealloc(dma->buflist,
932 				(dma->buf_count + entry->buf_count) *
933 				sizeof(*dma->buflist), GFP_KERNEL);
934 	if (!temp_buflist) {
935 		/* Free the entry because it isn't valid */
936 		drm_cleanup_buf_error(dev, entry);
937 		kfree(temp_pagelist);
938 		mutex_unlock(&dev->struct_mutex);
939 		atomic_dec(&dev->buf_alloc);
940 		return -ENOMEM;
941 	}
942 	dma->buflist = temp_buflist;
943 
944 	for (i = 0; i < entry->buf_count; i++) {
945 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
946 	}
947 
948 	/* No allocations failed, so now we can replace the original pagelist
949 	 * with the new one.
950 	 */
951 	if (dma->page_count) {
952 		kfree(dma->pagelist);
953 	}
954 	dma->pagelist = temp_pagelist;
955 
956 	dma->buf_count += entry->buf_count;
957 	dma->seg_count += entry->seg_count;
958 	dma->page_count += entry->seg_count << page_order;
959 	dma->byte_count += PAGE_SIZE * (entry->seg_count << page_order);
960 
961 	mutex_unlock(&dev->struct_mutex);
962 
963 	request->count = entry->buf_count;
964 	request->size = size;
965 
966 	if (request->flags & _DRM_PCI_BUFFER_RO)
967 		dma->flags = _DRM_DMA_USE_PCI_RO;
968 
969 	atomic_dec(&dev->buf_alloc);
970 	return 0;
971 
972 }
973 EXPORT_SYMBOL(drm_addbufs_pci);
974 
975 static int drm_addbufs_sg(struct drm_device * dev, struct drm_buf_desc * request)
976 {
977 	struct drm_device_dma *dma = dev->dma;
978 	struct drm_buf_entry *entry;
979 	struct drm_buf *buf;
980 	unsigned long offset;
981 	unsigned long agp_offset;
982 	int count;
983 	int order;
984 	int size;
985 	int alignment;
986 	int page_order;
987 	int total;
988 	int byte_count;
989 	int i;
990 	struct drm_buf **temp_buflist;
991 
992 	if (!drm_core_check_feature(dev, DRIVER_SG))
993 		return -EINVAL;
994 
995 	if (!dma)
996 		return -EINVAL;
997 
998 	if (!capable(CAP_SYS_ADMIN))
999 		return -EPERM;
1000 
1001 	count = request->count;
1002 	order = order_base_2(request->size);
1003 	size = 1 << order;
1004 
1005 	alignment = (request->flags & _DRM_PAGE_ALIGN)
1006 	    ? PAGE_ALIGN(size) : size;
1007 	page_order = order - PAGE_SHIFT > 0 ? order - PAGE_SHIFT : 0;
1008 	total = PAGE_SIZE << page_order;
1009 
1010 	byte_count = 0;
1011 	agp_offset = request->agp_start;
1012 
1013 	DRM_DEBUG("count:      %d\n", count);
1014 	DRM_DEBUG("order:      %d\n", order);
1015 	DRM_DEBUG("size:       %d\n", size);
1016 	DRM_DEBUG("agp_offset: %lu\n", agp_offset);
1017 	DRM_DEBUG("alignment:  %d\n", alignment);
1018 	DRM_DEBUG("page_order: %d\n", page_order);
1019 	DRM_DEBUG("total:      %d\n", total);
1020 
1021 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1022 		return -EINVAL;
1023 
1024 	spin_lock(&dev->count_lock);
1025 	if (dev->buf_use) {
1026 		spin_unlock(&dev->count_lock);
1027 		return -EBUSY;
1028 	}
1029 	atomic_inc(&dev->buf_alloc);
1030 	spin_unlock(&dev->count_lock);
1031 
1032 	mutex_lock(&dev->struct_mutex);
1033 	entry = &dma->bufs[order];
1034 	if (entry->buf_count) {
1035 		mutex_unlock(&dev->struct_mutex);
1036 		atomic_dec(&dev->buf_alloc);
1037 		return -ENOMEM;	/* May only call once for each order */
1038 	}
1039 
1040 	if (count < 0 || count > 4096) {
1041 		mutex_unlock(&dev->struct_mutex);
1042 		atomic_dec(&dev->buf_alloc);
1043 		return -EINVAL;
1044 	}
1045 
1046 	entry->buflist = kzalloc(count * sizeof(*entry->buflist),
1047 				GFP_KERNEL);
1048 	if (!entry->buflist) {
1049 		mutex_unlock(&dev->struct_mutex);
1050 		atomic_dec(&dev->buf_alloc);
1051 		return -ENOMEM;
1052 	}
1053 
1054 	entry->buf_size = size;
1055 	entry->page_order = page_order;
1056 
1057 	offset = 0;
1058 
1059 	while (entry->buf_count < count) {
1060 		buf = &entry->buflist[entry->buf_count];
1061 		buf->idx = dma->buf_count + entry->buf_count;
1062 		buf->total = alignment;
1063 		buf->order = order;
1064 		buf->used = 0;
1065 
1066 		buf->offset = (dma->byte_count + offset);
1067 		buf->bus_address = agp_offset + offset;
1068 		buf->address = (void *)(agp_offset + offset
1069 					+ (unsigned long)dev->sg->virtual);
1070 		buf->next = NULL;
1071 		buf->waiting = 0;
1072 		buf->pending = 0;
1073 		buf->file_priv = NULL;
1074 
1075 		buf->dev_priv_size = dev->driver->dev_priv_size;
1076 		buf->dev_private = kzalloc(buf->dev_priv_size, GFP_KERNEL);
1077 		if (!buf->dev_private) {
1078 			/* Set count correctly so we free the proper amount. */
1079 			entry->buf_count = count;
1080 			drm_cleanup_buf_error(dev, entry);
1081 			mutex_unlock(&dev->struct_mutex);
1082 			atomic_dec(&dev->buf_alloc);
1083 			return -ENOMEM;
1084 		}
1085 
1086 		DRM_DEBUG("buffer %d @ %p\n", entry->buf_count, buf->address);
1087 
1088 		offset += alignment;
1089 		entry->buf_count++;
1090 		byte_count += PAGE_SIZE << page_order;
1091 	}
1092 
1093 	DRM_DEBUG("byte_count: %d\n", byte_count);
1094 
1095 	temp_buflist = krealloc(dma->buflist,
1096 				(dma->buf_count + entry->buf_count) *
1097 				sizeof(*dma->buflist), GFP_KERNEL);
1098 	if (!temp_buflist) {
1099 		/* Free the entry because it isn't valid */
1100 		drm_cleanup_buf_error(dev, entry);
1101 		mutex_unlock(&dev->struct_mutex);
1102 		atomic_dec(&dev->buf_alloc);
1103 		return -ENOMEM;
1104 	}
1105 	dma->buflist = temp_buflist;
1106 
1107 	for (i = 0; i < entry->buf_count; i++) {
1108 		dma->buflist[i + dma->buf_count] = &entry->buflist[i];
1109 	}
1110 
1111 	dma->buf_count += entry->buf_count;
1112 	dma->seg_count += entry->seg_count;
1113 	dma->page_count += byte_count >> PAGE_SHIFT;
1114 	dma->byte_count += byte_count;
1115 
1116 	DRM_DEBUG("dma->buf_count : %d\n", dma->buf_count);
1117 	DRM_DEBUG("entry->buf_count : %d\n", entry->buf_count);
1118 
1119 	mutex_unlock(&dev->struct_mutex);
1120 
1121 	request->count = entry->buf_count;
1122 	request->size = size;
1123 
1124 	dma->flags = _DRM_DMA_USE_SG;
1125 
1126 	atomic_dec(&dev->buf_alloc);
1127 	return 0;
1128 }
1129 
1130 /**
1131  * Add buffers for DMA transfers (ioctl).
1132  *
1133  * \param inode device inode.
1134  * \param file_priv DRM file private.
1135  * \param cmd command.
1136  * \param arg pointer to a struct drm_buf_desc request.
1137  * \return zero on success or a negative number on failure.
1138  *
1139  * According with the memory type specified in drm_buf_desc::flags and the
1140  * build options, it dispatches the call either to addbufs_agp(),
1141  * addbufs_sg() or addbufs_pci() for AGP, scatter-gather or consistent
1142  * PCI memory respectively.
1143  */
1144 int drm_addbufs(struct drm_device *dev, void *data,
1145 		struct drm_file *file_priv)
1146 {
1147 	struct drm_buf_desc *request = data;
1148 	int ret;
1149 
1150 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1151 		return -EINVAL;
1152 
1153 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1154 		return -EINVAL;
1155 
1156 #if __OS_HAS_AGP
1157 	if (request->flags & _DRM_AGP_BUFFER)
1158 		ret = drm_addbufs_agp(dev, request);
1159 	else
1160 #endif
1161 	if (request->flags & _DRM_SG_BUFFER)
1162 		ret = drm_addbufs_sg(dev, request);
1163 	else if (request->flags & _DRM_FB_BUFFER)
1164 		ret = -EINVAL;
1165 	else
1166 		ret = drm_addbufs_pci(dev, request);
1167 
1168 	return ret;
1169 }
1170 
1171 /**
1172  * Get information about the buffer mappings.
1173  *
1174  * This was originally mean for debugging purposes, or by a sophisticated
1175  * client library to determine how best to use the available buffers (e.g.,
1176  * large buffers can be used for image transfer).
1177  *
1178  * \param inode device inode.
1179  * \param file_priv DRM file private.
1180  * \param cmd command.
1181  * \param arg pointer to a drm_buf_info structure.
1182  * \return zero on success or a negative number on failure.
1183  *
1184  * Increments drm_device::buf_use while holding the drm_device::count_lock
1185  * lock, preventing of allocating more buffers after this call. Information
1186  * about each requested buffer is then copied into user space.
1187  */
1188 int drm_infobufs(struct drm_device *dev, void *data,
1189 		 struct drm_file *file_priv)
1190 {
1191 	struct drm_device_dma *dma = dev->dma;
1192 	struct drm_buf_info *request = data;
1193 	int i;
1194 	int count;
1195 
1196 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1197 		return -EINVAL;
1198 
1199 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1200 		return -EINVAL;
1201 
1202 	if (!dma)
1203 		return -EINVAL;
1204 
1205 	spin_lock(&dev->count_lock);
1206 	if (atomic_read(&dev->buf_alloc)) {
1207 		spin_unlock(&dev->count_lock);
1208 		return -EBUSY;
1209 	}
1210 	++dev->buf_use;		/* Can't allocate more after this call */
1211 	spin_unlock(&dev->count_lock);
1212 
1213 	for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1214 		if (dma->bufs[i].buf_count)
1215 			++count;
1216 	}
1217 
1218 	DRM_DEBUG("count = %d\n", count);
1219 
1220 	if (request->count >= count) {
1221 		for (i = 0, count = 0; i < DRM_MAX_ORDER + 1; i++) {
1222 			if (dma->bufs[i].buf_count) {
1223 				struct drm_buf_desc __user *to =
1224 				    &request->list[count];
1225 				struct drm_buf_entry *from = &dma->bufs[i];
1226 				struct drm_freelist *list = &dma->bufs[i].freelist;
1227 				if (copy_to_user(&to->count,
1228 						 &from->buf_count,
1229 						 sizeof(from->buf_count)) ||
1230 				    copy_to_user(&to->size,
1231 						 &from->buf_size,
1232 						 sizeof(from->buf_size)) ||
1233 				    copy_to_user(&to->low_mark,
1234 						 &list->low_mark,
1235 						 sizeof(list->low_mark)) ||
1236 				    copy_to_user(&to->high_mark,
1237 						 &list->high_mark,
1238 						 sizeof(list->high_mark)))
1239 					return -EFAULT;
1240 
1241 				DRM_DEBUG("%d %d %d %d %d\n",
1242 					  i,
1243 					  dma->bufs[i].buf_count,
1244 					  dma->bufs[i].buf_size,
1245 					  dma->bufs[i].freelist.low_mark,
1246 					  dma->bufs[i].freelist.high_mark);
1247 				++count;
1248 			}
1249 		}
1250 	}
1251 	request->count = count;
1252 
1253 	return 0;
1254 }
1255 
1256 /**
1257  * Specifies a low and high water mark for buffer allocation
1258  *
1259  * \param inode device inode.
1260  * \param file_priv DRM file private.
1261  * \param cmd command.
1262  * \param arg a pointer to a drm_buf_desc structure.
1263  * \return zero on success or a negative number on failure.
1264  *
1265  * Verifies that the size order is bounded between the admissible orders and
1266  * updates the respective drm_device_dma::bufs entry low and high water mark.
1267  *
1268  * \note This ioctl is deprecated and mostly never used.
1269  */
1270 int drm_markbufs(struct drm_device *dev, void *data,
1271 		 struct drm_file *file_priv)
1272 {
1273 	struct drm_device_dma *dma = dev->dma;
1274 	struct drm_buf_desc *request = data;
1275 	int order;
1276 	struct drm_buf_entry *entry;
1277 
1278 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1279 		return -EINVAL;
1280 
1281 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1282 		return -EINVAL;
1283 
1284 	if (!dma)
1285 		return -EINVAL;
1286 
1287 	DRM_DEBUG("%d, %d, %d\n",
1288 		  request->size, request->low_mark, request->high_mark);
1289 	order = order_base_2(request->size);
1290 	if (order < DRM_MIN_ORDER || order > DRM_MAX_ORDER)
1291 		return -EINVAL;
1292 	entry = &dma->bufs[order];
1293 
1294 	if (request->low_mark < 0 || request->low_mark > entry->buf_count)
1295 		return -EINVAL;
1296 	if (request->high_mark < 0 || request->high_mark > entry->buf_count)
1297 		return -EINVAL;
1298 
1299 	entry->freelist.low_mark = request->low_mark;
1300 	entry->freelist.high_mark = request->high_mark;
1301 
1302 	return 0;
1303 }
1304 
1305 /**
1306  * Unreserve the buffers in list, previously reserved using drmDMA.
1307  *
1308  * \param inode device inode.
1309  * \param file_priv DRM file private.
1310  * \param cmd command.
1311  * \param arg pointer to a drm_buf_free structure.
1312  * \return zero on success or a negative number on failure.
1313  *
1314  * Calls free_buffer() for each used buffer.
1315  * This function is primarily used for debugging.
1316  */
1317 int drm_freebufs(struct drm_device *dev, void *data,
1318 		 struct drm_file *file_priv)
1319 {
1320 	struct drm_device_dma *dma = dev->dma;
1321 	struct drm_buf_free *request = data;
1322 	int i;
1323 	int idx;
1324 	struct drm_buf *buf;
1325 
1326 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1327 		return -EINVAL;
1328 
1329 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1330 		return -EINVAL;
1331 
1332 	if (!dma)
1333 		return -EINVAL;
1334 
1335 	DRM_DEBUG("%d\n", request->count);
1336 	for (i = 0; i < request->count; i++) {
1337 		if (copy_from_user(&idx, &request->list[i], sizeof(idx)))
1338 			return -EFAULT;
1339 		if (idx < 0 || idx >= dma->buf_count) {
1340 			DRM_ERROR("Index %d (of %d max)\n",
1341 				  idx, dma->buf_count - 1);
1342 			return -EINVAL;
1343 		}
1344 		buf = dma->buflist[idx];
1345 		if (buf->file_priv != file_priv) {
1346 			DRM_ERROR("Process %d freeing buffer not owned\n",
1347 				  task_pid_nr(current));
1348 			return -EINVAL;
1349 		}
1350 		drm_free_buffer(dev, buf);
1351 	}
1352 
1353 	return 0;
1354 }
1355 
1356 /**
1357  * Maps all of the DMA buffers into client-virtual space (ioctl).
1358  *
1359  * \param inode device inode.
1360  * \param file_priv DRM file private.
1361  * \param cmd command.
1362  * \param arg pointer to a drm_buf_map structure.
1363  * \return zero on success or a negative number on failure.
1364  *
1365  * Maps the AGP, SG or PCI buffer region with vm_mmap(), and copies information
1366  * about each buffer into user space. For PCI buffers, it calls vm_mmap() with
1367  * offset equal to 0, which drm_mmap() interpretes as PCI buffers and calls
1368  * drm_mmap_dma().
1369  */
1370 int drm_mapbufs(struct drm_device *dev, void *data,
1371 	        struct drm_file *file_priv)
1372 {
1373 	struct drm_device_dma *dma = dev->dma;
1374 	int retcode = 0;
1375 	const int zero = 0;
1376 	unsigned long virtual;
1377 	unsigned long address;
1378 	struct drm_buf_map *request = data;
1379 	int i;
1380 
1381 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1382 		return -EINVAL;
1383 
1384 	if (!drm_core_check_feature(dev, DRIVER_HAVE_DMA))
1385 		return -EINVAL;
1386 
1387 	if (!dma)
1388 		return -EINVAL;
1389 
1390 	spin_lock(&dev->count_lock);
1391 	if (atomic_read(&dev->buf_alloc)) {
1392 		spin_unlock(&dev->count_lock);
1393 		return -EBUSY;
1394 	}
1395 	dev->buf_use++;		/* Can't allocate more after this call */
1396 	spin_unlock(&dev->count_lock);
1397 
1398 	if (request->count >= dma->buf_count) {
1399 		if ((drm_core_has_AGP(dev) && (dma->flags & _DRM_DMA_USE_AGP))
1400 		    || (drm_core_check_feature(dev, DRIVER_SG)
1401 			&& (dma->flags & _DRM_DMA_USE_SG))) {
1402 			struct drm_local_map *map = dev->agp_buffer_map;
1403 			unsigned long token = dev->agp_buffer_token;
1404 
1405 			if (!map) {
1406 				retcode = -EINVAL;
1407 				goto done;
1408 			}
1409 			virtual = vm_mmap(file_priv->filp, 0, map->size,
1410 					  PROT_READ | PROT_WRITE,
1411 					  MAP_SHARED,
1412 					  token);
1413 		} else {
1414 			virtual = vm_mmap(file_priv->filp, 0, dma->byte_count,
1415 					  PROT_READ | PROT_WRITE,
1416 					  MAP_SHARED, 0);
1417 		}
1418 		if (virtual > -1024UL) {
1419 			/* Real error */
1420 			retcode = (signed long)virtual;
1421 			goto done;
1422 		}
1423 		request->virtual = (void __user *)virtual;
1424 
1425 		for (i = 0; i < dma->buf_count; i++) {
1426 			if (copy_to_user(&request->list[i].idx,
1427 					 &dma->buflist[i]->idx,
1428 					 sizeof(request->list[0].idx))) {
1429 				retcode = -EFAULT;
1430 				goto done;
1431 			}
1432 			if (copy_to_user(&request->list[i].total,
1433 					 &dma->buflist[i]->total,
1434 					 sizeof(request->list[0].total))) {
1435 				retcode = -EFAULT;
1436 				goto done;
1437 			}
1438 			if (copy_to_user(&request->list[i].used,
1439 					 &zero, sizeof(zero))) {
1440 				retcode = -EFAULT;
1441 				goto done;
1442 			}
1443 			address = virtual + dma->buflist[i]->offset;	/* *** */
1444 			if (copy_to_user(&request->list[i].address,
1445 					 &address, sizeof(address))) {
1446 				retcode = -EFAULT;
1447 				goto done;
1448 			}
1449 		}
1450 	}
1451       done:
1452 	request->count = dma->buf_count;
1453 	DRM_DEBUG("%d buffers, retcode = %d\n", request->count, retcode);
1454 
1455 	return retcode;
1456 }
1457 
1458 int drm_dma_ioctl(struct drm_device *dev, void *data,
1459 		  struct drm_file *file_priv)
1460 {
1461 	if (drm_core_check_feature(dev, DRIVER_MODESET))
1462 		return -EINVAL;
1463 
1464 	if (dev->driver->dma_ioctl)
1465 		return dev->driver->dma_ioctl(dev, data, file_priv);
1466 	else
1467 		return -EINVAL;
1468 }
1469 
1470 struct drm_local_map *drm_getsarea(struct drm_device *dev)
1471 {
1472 	struct drm_map_list *entry;
1473 
1474 	list_for_each_entry(entry, &dev->maplist, head) {
1475 		if (entry->map && entry->map->type == _DRM_SHM &&
1476 		    (entry->map->flags & _DRM_CONTAINS_LOCK)) {
1477 			return entry->map;
1478 		}
1479 	}
1480 	return NULL;
1481 }
1482 EXPORT_SYMBOL(drm_getsarea);
1483