/*- * Copyright 2003 Eric Anholt. * All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice (including the next * paragraph) shall be included in all copies or substantial portions of the * Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /** * \file drm_pci.h * \brief PCI consistent, DMA-accessible memory allocation. * * \author Eric Anholt */ #include "drmP.h" /**********************************************************************/ /** \name PCI memory */ /*@{*/ #if defined(__FreeBSD__) static void drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error) { drm_dma_handle_t *dmah = arg; if (error != 0) return; KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count")); dmah->busaddr = segs[0].ds_addr; } #endif /** * \brief Allocate a physically contiguous DMA-accessible consistent * memory block. */ drm_dma_handle_t * drm_pci_alloc(drm_device_t *dev, size_t size, size_t align, dma_addr_t maxaddr) { drm_dma_handle_t *dmah; int ret; /* Need power-of-two alignment, so fail the allocation if it isn't. */ if ((align & (align - 1)) != 0) { DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n", (int)align); return NULL; } dmah = malloc(sizeof(drm_dma_handle_t), M_DRM, M_ZERO | M_NOWAIT); if (dmah == NULL) return NULL; #ifdef __FreeBSD__ ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */ maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */ NULL, NULL, /* filtfunc, filtfuncargs */ size, 1, size, /* maxsize, nsegs, maxsegsize */ BUS_DMA_ALLOCNOW, NULL, NULL, /* flags, lockfunc, lockfuncargs */ &dmah->tag); if (ret != 0) { free(dmah, M_DRM); return NULL; } ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr, BUS_DMA_NOWAIT, &dmah->map); if (ret != 0) { bus_dma_tag_destroy(dmah->tag); free(dmah, M_DRM); return NULL; } ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size, drm_pci_busdma_callback, dmah, 0); if (ret != 0) { bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map); bus_dma_tag_destroy(dmah->tag); free(dmah, M_DRM); return NULL; } #elif defined(__NetBSD__) ret = bus_dmamem_alloc(dev->dma_tag, size, align, PAGE_SIZE, &dmah->seg, 1, &nsegs, BUS_DMA_NOWAIT); if ((ret != 0) || (nsegs != 1)) { free(dmah, M_DRM); return NULL; } ret = bus_dmamem_map(dev->dma_tag, &dmah->seg, 1, size, &dmah->addr, BUS_DMA_NOWAIT); if (ret != 0) { bus_dmamem_free(dev->dma_tag, &dmah->seg, 1); free(dmah, M_DRM); return NULL; } dmah->dmaaddr = h->seg.ds_addr; #endif return dmah; } /** * \brief Free a DMA-accessible consistent memory block. */ void drm_pci_free(drm_device_t *dev, drm_dma_handle_t *dmah) { if (dmah == NULL) return; #if defined(__FreeBSD__) bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map); bus_dma_tag_destroy(dmah->tag); #elif defined(__NetBSD__) bus_dmamem_free(dev->dma_tag, &dmah->seg, 1); #endif free(dmah, M_DRM); } /*@}*/ 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700

/**
 * \file drm_vm.c
 * Memory mapping for DRM
 *
 * \author Rickard E. (Rik) Faith <faith@valinux.com>
 * \author Gareth Hughes <gareth@valinux.com>
 */

/*
 * Created: Mon Jan  4 08:58:31 1999 by faith@valinux.com
 *
 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
 * All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#include "drmP.h"

/**
 * \c nopage method for AGP virtual memory.
 *
 * \param vma virtual memory area.
 * \param address access address.
 * \return pointer to the page structure.
 *
 * Find the right map and if it's AGP memory find the real physical page to
 * map, get the page, increment the use count and return it.
 */
#if __OS_HAS_AGP
static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
						unsigned long address)
{
	drm_file_t *priv = vma->vm_file->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_map_t *map = NULL;
	drm_map_list_t *r_list;
	struct list_head *list;

	/*
	 * Find the right map
	 */
	if (!drm_core_has_AGP(dev))
		goto vm_nopage_error;

	if (!dev->agp || !dev->agp->cant_use_aperture)
		goto vm_nopage_error;

	list_for_each(list, &dev->maplist->head) {
		r_list = list_entry(list, drm_map_list_t, head);
		map = r_list->map;
		if (!map)
			continue;
		if (map->offset == VM_OFFSET(vma))
			break;
	}

	if (map && map->type == _DRM_AGP) {
		unsigned long offset = address - vma->vm_start;
		unsigned long baddr = VM_OFFSET(vma) + offset;
		struct drm_agp_mem *agpmem;
		struct page *page;

#ifdef __alpha__
		/*
		 * Adjust to a bus-relative address
		 */
		baddr -= dev->hose->mem_space->start;
#endif

		/*
		 * It's AGP memory - find the real physical page to map
		 */
		for (agpmem = dev->agp->memory; agpmem; agpmem = agpmem->next) {
			if (agpmem->bound <= baddr &&
			    agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
				break;
		}

		if (!agpmem)
			goto vm_nopage_error;

		/*
		 * Get the page, inc the use count, and return it
		 */
		offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
		page = virt_to_page(__va(agpmem->memory->memory[offset]));
		get_page(page);

#if 0
		/* page_count() not defined everywhere */
		DRM_DEBUG
		    ("baddr = 0x%lx page = 0x%p, offset = 0x%lx, count=%d\n",
		     baddr, __va(agpmem->memory->memory[offset]), offset,
		     page_count(page));
#endif

		return page;
	}
      vm_nopage_error:
	return NOPAGE_SIGBUS;	/* Disallow mremap */
}
#else				/* __OS_HAS_AGP */
static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
						unsigned long address)
{
	return NOPAGE_SIGBUS;
}
#endif				/* __OS_HAS_AGP */

/**
 * \c nopage method for shared virtual memory.
 *
 * \param vma virtual memory area.
 * \param address access address.
 * \return pointer to the page structure.
 *
 * Get the the mapping, find the real physical page to map, get the page, and
 * return it.
 */
static __inline__ struct page *drm_do_vm_shm_nopage(struct vm_area_struct *vma,
						    unsigned long address)
{
	drm_map_t *map = (drm_map_t *) vma->vm_private_data;
	unsigned long offset;
	unsigned long i;
	struct page *page;

	if (address > vma->vm_end)
		return NOPAGE_SIGBUS;	/* Disallow mremap */
	if (!map)
		return NOPAGE_OOM;	/* Nothing allocated */

	offset = address - vma->vm_start;
	i = (unsigned long)map->handle + offset;
	page = vmalloc_to_page((void *)i);
	if (!page)
		return NOPAGE_OOM;
	get_page(page);

	DRM_DEBUG("shm_nopage 0x%lx\n", address);
	return page;
}

/**
 * \c close method for shared virtual memory.
 *
 * \param vma virtual memory area.
 *
 * Deletes map information if we are the last
 * person to close a mapping and it's not in the global maplist.
 */
void drm_vm_shm_close(struct vm_area_struct *vma)
{
	drm_file_t *priv = vma->vm_file->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_vma_entry_t *pt, *prev, *next;
	drm_map_t *map;
	drm_map_list_t *r_list;
	struct list_head *list;
	int found_maps = 0;

	DRM_DEBUG("0x%08lx,0x%08lx\n",
		  vma->vm_start, vma->vm_end - vma->vm_start);
	atomic_dec(&dev->vma_count);

	map = vma->vm_private_data;

	down(&dev->struct_sem);
	for (pt = dev->vmalist, prev = NULL; pt; pt = next) {
		next = pt->next;
		if (pt->vma->vm_private_data == map)
			found_maps++;
		if (pt->vma == vma) {
			if (prev) {
				prev->next = pt->next;
			} else {
				dev->vmalist = pt->next;
			}
			drm_free(pt, sizeof(*pt), DRM_MEM_VMAS);
		} else {
			prev = pt;
		}
	}
	/* We were the only map that was found */
	if (found_maps == 1 && map->flags & _DRM_REMOVABLE) {
		/* Check to see if we are in the maplist, if we are not, then
		 * we delete this mappings information.
		 */
		found_maps = 0;
		list = &dev->maplist->head;
		list_for_each(list, &dev->maplist->head) {
			r_list = list_entry(list, drm_map_list_t, head);
			if (r_list->map == map)
				found_maps++;
		}

		if (!found_maps) {
			switch (map->type) {
			case _DRM_REGISTERS:
			case _DRM_FRAME_BUFFER:
				if (drm_core_has_MTRR(dev) && map->mtrr >= 0) {
					int retcode;
					retcode = mtrr_del(map->mtrr,
							   map->offset,
							   map->size);
					DRM_DEBUG("mtrr_del = %d\n", retcode);
				}
				drm_ioremapfree(map->handle, map->size, dev);
				break;
			case _DRM_SHM:
				vfree(map->handle);
				break;
			case _DRM_AGP:
			case _DRM_SCATTER_GATHER:
				break;
			case _DRM_CONSISTENT:
				drm_pci_free(dev, map->size, map->handle,
					     map->offset);
				break;
			}
			drm_free(map, sizeof(*map), DRM_MEM_MAPS);
		}
	}
	up(&dev->struct_sem);
}

/**
 * \c nopage method for DMA virtual memory.
 *
 * \param vma virtual memory area.
 * \param address access address.
 * \return pointer to the page structure.
 *
 * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
 */
static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
						    unsigned long address)
{
	drm_file_t *priv = vma->vm_file->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_device_dma_t *dma = dev->dma;
	unsigned long offset;
	unsigned long page_nr;
	struct page *page;

	if (!dma)
		return NOPAGE_SIGBUS;	/* Error */
	if (address > vma->vm_end)
		return NOPAGE_SIGBUS;	/* Disallow mremap */
	if (!dma->pagelist)
		return NOPAGE_OOM;	/* Nothing allocated */

	offset = address - vma->vm_start;	/* vm_[pg]off[set] should be 0 */
	page_nr = offset >> PAGE_SHIFT;
	page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK))));

	get_page(page);

	DRM_DEBUG("dma_nopage 0x%lx (page %lu)\n", address, page_nr);
	return page;
}

/**
 * \c nopage method for scatter-gather virtual memory.
 *
 * \param vma virtual memory area.
 * \param address access address.
 * \return pointer to the page structure.
 *
 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
 */
static __inline__ struct page *drm_do_vm_sg_nopage(struct vm_area_struct *vma,
						   unsigned long address)
{
	drm_map_t *map = (drm_map_t *) vma->vm_private_data;
	drm_file_t *priv = vma->vm_file->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_sg_mem_t *entry = dev->sg;
	unsigned long offset;
	unsigned long map_offset;
	unsigned long page_offset;
	struct page *page;

	if (!entry)
		return NOPAGE_SIGBUS;	/* Error */
	if (address > vma->vm_end)
		return NOPAGE_SIGBUS;	/* Disallow mremap */
	if (!entry->pagelist)
		return NOPAGE_OOM;	/* Nothing allocated */

	offset = address - vma->vm_start;
	map_offset = map->offset - dev->sg->handle;
	page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
	page = entry->pagelist[page_offset];
	get_page(page);

	return page;
}

#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,0)

static struct page *drm_vm_nopage(struct vm_area_struct *vma,
				  unsigned long address, int *type)
{
	if (type)
		*type = VM_FAULT_MINOR;
	return drm_do_vm_nopage(vma, address);
}

static struct page *drm_vm_shm_nopage(struct vm_area_struct *vma,
				      unsigned long address, int *type)
{
	if (type)
		*type = VM_FAULT_MINOR;
	return drm_do_vm_shm_nopage(vma, address);
}

static struct page *drm_vm_dma_nopage(struct vm_area_struct *vma,
				      unsigned long address, int *type)
{
	if (type)
		*type = VM_FAULT_MINOR;
	return drm_do_vm_dma_nopage(vma, address);
}

static struct page *drm_vm_sg_nopage(struct vm_area_struct *vma,
				     unsigned long address, int *type)
{
	if (type)
		*type = VM_FAULT_MINOR;
	return drm_do_vm_sg_nopage(vma, address);
}

#else				/* LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,0) */

static struct page *drm_vm_nopage(struct vm_area_struct *vma,
				  unsigned long address, int unused)
{
	return drm_do_vm_nopage(vma, address);
}

static struct page *drm_vm_shm_nopage(struct vm_area_struct *vma,
				      unsigned long address, int unused)
{
	return drm_do_vm_shm_nopage(vma, address);
}

static struct page *drm_vm_dma_nopage(struct vm_area_struct *vma,
				      unsigned long address, int unused)
{
	return drm_do_vm_dma_nopage(vma, address);
}

static struct page *drm_vm_sg_nopage(struct vm_area_struct *vma,
				     unsigned long address, int unused)
{
	return drm_do_vm_sg_nopage(vma, address);
}

#endif

/** AGP virtual memory operations */
static struct vm_operations_struct drm_vm_ops = {
	.nopage = drm_vm_nopage,
	.open = drm_vm_open,
	.close = drm_vm_close,
};

/** Shared virtual memory operations */
static struct vm_operations_struct drm_vm_shm_ops = {
	.nopage = drm_vm_shm_nopage,
	.open = drm_vm_open,
	.close = drm_vm_shm_close,
};

/** DMA virtual memory operations */
static struct vm_operations_struct drm_vm_dma_ops = {
	.nopage = drm_vm_dma_nopage,
	.open = drm_vm_open,
	.close = drm_vm_close,
};

/** Scatter-gather virtual memory operations */
static struct vm_operations_struct drm_vm_sg_ops = {
	.nopage = drm_vm_sg_nopage,
	.open = drm_vm_open,
	.close = drm_vm_close,
};

/**
 * \c open method for shared virtual memory.
 *
 * \param vma virtual memory area.
 *
 * Create a new drm_vma_entry structure as the \p vma private data entry and
 * add it to drm_device::vmalist.
 */
void drm_vm_open(struct vm_area_struct *vma)
{
	drm_file_t *priv = vma->vm_file->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_vma_entry_t *vma_entry;

	DRM_DEBUG("0x%08lx,0x%08lx\n",
		  vma->vm_start, vma->vm_end - vma->vm_start);
	atomic_inc(&dev->vma_count);

	vma_entry = drm_alloc(sizeof(*vma_entry), DRM_MEM_VMAS);
	if (vma_entry) {
		down(&dev->struct_sem);
		vma_entry->vma = vma;
		vma_entry->next = dev->vmalist;
		vma_entry->pid = current->pid;
		dev->vmalist = vma_entry;
		up(&dev->struct_sem);
	}
}

/**
 * \c close method for all virtual memory types.
 *
 * \param vma virtual memory area.
 *
 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
 * free it.
 */
void drm_vm_close(struct vm_area_struct *vma)
{
	drm_file_t *priv = vma->vm_file->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_vma_entry_t *pt, *prev;

	DRM_DEBUG("0x%08lx,0x%08lx\n",
		  vma->vm_start, vma->vm_end - vma->vm_start);
	atomic_dec(&dev->vma_count);

	down(&dev->struct_sem);
	for (pt = dev->vmalist, prev = NULL; pt; prev = pt, pt = pt->next) {
		if (pt->vma == vma) {
			if (prev) {
				prev->next = pt->next;
			} else {
				dev->vmalist = pt->next;
			}
			drm_free(pt, sizeof(*pt), DRM_MEM_VMAS);
			break;
		}
	}
	up(&dev->struct_sem);
}

/**
 * mmap DMA memory.
 *
 * \param filp file pointer.
 * \param vma virtual memory area.
 * \return zero on success or a negative number on failure.
 *
 * Sets the virtual memory area operations structure to vm_dma_ops, the file
 * pointer, and calls vm_open().
 */
int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev;
	drm_device_dma_t *dma;
	unsigned long length = vma->vm_end - vma->vm_start;

	lock_kernel();
	dev = priv->head->dev;
	dma = dev->dma;
	DRM_DEBUG("start = 0x%lx, end = 0x%lx, offset = 0x%lx\n",
		  vma->vm_start, vma->vm_end, VM_OFFSET(vma));

	/* Length must match exact page count */
	if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
		unlock_kernel();
		return -EINVAL;
	}
	unlock_kernel();

	vma->vm_ops = &drm_vm_dma_ops;

#if LINUX_VERSION_CODE <= 0x02040e	/* KERNEL_VERSION(2,4,14) */
	vma->vm_flags |= VM_LOCKED | VM_SHM;	/* Don't swap */
#else
	vma->vm_flags |= VM_RESERVED;	/* Don't swap */
#endif

	vma->vm_file = filp;	/* Needed for drm_vm_open() */
	drm_vm_open(vma);
	return 0;
}

unsigned long drm_core_get_map_ofs(drm_map_t * map)
{
	return map->offset;
}
EXPORT_SYMBOL(drm_core_get_map_ofs);

unsigned long drm_core_get_reg_ofs(struct drm_device *dev)
{
#ifdef __alpha__
	return dev->hose->dense_mem_base - dev->hose->mem_space->start;
#else
	return 0;
#endif
}
EXPORT_SYMBOL(drm_core_get_reg_ofs);

/**
 * mmap DMA memory.
 *
 * \param filp file pointer.
 * \param vma virtual memory area.
 * \return zero on success or a negative number on failure.
 *
 * If the virtual memory area has no offset associated with it then it's a DMA
 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
 * checks that the restricted flag is not set, sets the virtual memory operations
 * according to the mapping type and remaps the pages. Finally sets the file
 * pointer and calls vm_open().
 */
int drm_mmap(struct file *filp, struct vm_area_struct *vma)
{
	drm_file_t *priv = filp->private_data;
	drm_device_t *dev = priv->head->dev;
	drm_map_t *map = NULL;
	drm_map_list_t *r_list;
	unsigned long offset = 0;
	struct list_head *list;

	DRM_DEBUG("start = 0x%lx, end = 0x%lx, offset = 0x%lx\n",
		  vma->vm_start, vma->vm_end, VM_OFFSET(vma));

	if (!priv->authenticated)
		return -EACCES;

	/* We check for "dma". On Apple's UniNorth, it's valid to have
	 * the AGP mapped at physical address 0
	 * --BenH.
	 */
	if (!VM_OFFSET(vma)
#if __OS_HAS_AGP
	    && (!dev->agp
		|| dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
#endif
	    )
		return drm_mmap_dma(filp, vma);

	/* A sequential search of a linked list is
	   fine here because: 1) there will only be
	   about 5-10 entries in the list and, 2) a
	   DRI client only has to do this mapping
	   once, so it doesn't have to be optimized
	   for performance, even if the list was a
	   bit longer. */
	list_for_each(list, &dev->maplist->head) {
		unsigned long off;

		r_list = list_entry(list, drm_map_list_t, head);
		map = r_list->map;
		if (!map)
			continue;
		off = dev->driver->get_map_ofs(map);
		if (off == VM_OFFSET(vma))
			break;
	}

	if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
		return -EPERM;

	/* Check for valid size. */
	if (map->size < vma->vm_end - vma->vm_start)
		return -EINVAL;

	if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
		vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
#if defined(__i386__) || defined(__x86_64__)
		pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
#else
		/* Ye gads this is ugly.  With more thought
		   we could move this up higher and use
		   `protection_map' instead.  */
		vma->vm_page_prot =
		    __pgprot(pte_val
			     (pte_wrprotect
			      (__pte(pgprot_val(vma->vm_page_prot)))));
#endif
	}

	switch (map->type) {
	case _DRM_AGP:
		if (drm_core_has_AGP(dev) && dev->agp->cant_use_aperture) {
			/*
			 * On some platforms we can't talk to bus dma address from the CPU, so for
			 * memory of type DRM_AGP, we'll deal with sorting out the real physical
			 * pages and mappings in nopage()
			 */
#if defined(__powerpc__)
			pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
#endif
			vma->vm_ops = &drm_vm_ops;
			break;
		}
		/* fall through to _DRM_FRAME_BUFFER... */
	case _DRM_FRAME_BUFFER:
	case _DRM_REGISTERS:
		if (VM_OFFSET(vma) >= __pa(high_memory)) {
#if defined(__i386__) || defined(__x86_64__)
			if (boot_cpu_data.x86 > 3 && map->type != _DRM_AGP) {
				pgprot_val(vma->vm_page_prot) |= _PAGE_PCD;
				pgprot_val(vma->vm_page_prot) &= ~_PAGE_PWT;
			}
#elif defined(__powerpc__)
			pgprot_val(vma->vm_page_prot) |=
			    _PAGE_NO_CACHE | _PAGE_GUARDED;
#endif
			vma->vm_flags |= VM_IO;	/* not in core dump */
		}
#if defined(__ia64__)
		if (map->type != _DRM_AGP)
			vma->vm_page_prot =
			    pgprot_writecombine(vma->vm_page_prot);
#endif
		offset = dev->driver->get_reg_ofs(dev);
#ifdef __sparc__
		if (io_remap_page_range(DRM_RPR_ARG(vma) vma->vm_start,
					VM_OFFSET(vma) + offset,
					vma->vm_end - vma->vm_start,
					vma->vm_page_prot, 0))
#else
		if (remap_pfn_range(vma, vma->vm_start,
				     (VM_OFFSET(vma) + offset) >> PAGE_SHIFT,
				     vma->vm_end - vma->vm_start,
				     vma->vm_page_prot))
#endif
			return -EAGAIN;