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