drivers/char/drm/drm_vm.c

   1 /**
   2  * \file drm_vm.c
   3  * Memory mapping for DRM
   4  *
   5  * \author Rickard E. (Rik) Faith <faith@valinux.com>
   6  * \author Gareth Hughes <gareth@valinux.com>
   7  */
   8
   9 /*
  10  * Created: Mon Jan  4 08:58:31 1999 by faith@valinux.com
  11  *
  12  * Copyright 1999 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 "drmP.h"
  37 #if defined(__ia64__)
  38 #include <linux/efi.h>
  39 #endif
  40
  41 static void drm_vm_open(struct vm_area_struct *vma);
  42 static void drm_vm_close(struct vm_area_struct *vma);
  43
  44 pgprot_t drm_io_prot(uint32_t map_type, struct vm_area_struct *vma)
  45 {
  46         pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
  47
  48 #if defined(__i386__) || defined(__x86_64__)
  49         if (boot_cpu_data.x86 > 3 && map_type != _DRM_AGP) {
  50                 pgprot_val(tmp) |= _PAGE_PCD;
  51                 pgprot_val(tmp) &= ~_PAGE_PWT;
  52         }
  53 #elif defined(__powerpc__)
  54         pgprot_val(tmp) |= _PAGE_NO_CACHE;
  55         if (map_type == _DRM_REGISTERS)
  56                 pgprot_val(tmp) |= _PAGE_GUARDED;
  57 #endif
  58 #if defined(__ia64__)
  59         if (efi_range_is_wc(vma->vm_start, vma->vm_end -
  60                                     vma->vm_start))
  61                 tmp = pgprot_writecombine(tmp);
  62         else
  63                 tmp = pgprot_noncached(tmp);
  64 #endif
  65         return tmp;
  66 }
  67
  68 /**
  69  * \c nopage method for AGP virtual memory.
  70  *
  71  * \param vma virtual memory area.
  72  * \param address access address.
  73  * \return pointer to the page structure.
  74  *
  75  * Find the right map and if it's AGP memory find the real physical page to
  76  * map, get the page, increment the use count and return it.
  77  */
  78 #if __OS_HAS_AGP
  79 static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
  80                                                 unsigned long address)
  81 {
  82         drm_file_t *priv = vma->vm_file->private_data;
  83         drm_device_t *dev = priv->head->dev;
  84         drm_map_t *map = NULL;
  85         drm_map_list_t *r_list;
  86         drm_hash_item_t *hash;
  87
  88         /*
  89          * Find the right map
  90          */
  91         if (!drm_core_has_AGP(dev))
  92                 goto vm_nopage_error;
  93
  94         if (!dev->agp || !dev->agp->cant_use_aperture)
  95                 goto vm_nopage_error;
  96
  97         if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
  98                 goto vm_nopage_error;
  99
 100         r_list = drm_hash_entry(hash, drm_map_list_t, hash);
 101         map = r_list->map;
 102
 103         if (map && map->type == _DRM_AGP) {
 104                 unsigned long offset = address - vma->vm_start;
 105                 unsigned long baddr = map->offset + offset;
 106                 struct drm_agp_mem *agpmem;
 107                 struct page *page;
 108
 109 #ifdef __alpha__
 110                 /*
 111                  * Adjust to a bus-relative address
 112                  */
 113                 baddr -= dev->hose->mem_space->start;
 114 #endif
 115
 116                 /*
 117                  * It's AGP memory - find the real physical page to map
 118                  */
 119                 for (agpmem = dev->agp->memory; agpmem; agpmem = agpmem->next) {
 120                         if (agpmem->bound <= baddr &&
 121                             agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
 122                                 break;
 123                 }
 124
 125                 if (!agpmem)
 126                         goto vm_nopage_error;
 127
 128                 /*
 129                  * Get the page, inc the use count, and return it
 130                  */
 131                 offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
 132                 page = virt_to_page(__va(agpmem->memory->memory[offset]));
 133                 get_page(page);
 134
 135                 DRM_DEBUG
 136                     ("baddr = 0x%lx page = 0x%p, offset = 0x%lx, count=%d\n",
 137                      baddr, __va(agpmem->memory->memory[offset]), offset,
 138                      page_count(page));
 139
 140                 return page;
 141         }
 142       vm_nopage_error:
 143         return NOPAGE_SIGBUS;   /* Disallow mremap */
 144 }
 145 #else                           /* __OS_HAS_AGP */
 146 static __inline__ struct page *drm_do_vm_nopage(struct vm_area_struct *vma,
 147                                                 unsigned long address)
 148 {
 149         return NOPAGE_SIGBUS;
 150 }
 151 #endif                          /* __OS_HAS_AGP */
 152
 153 /**
 154  * \c nopage method for shared virtual memory.
 155  *
 156  * \param vma virtual memory area.
 157  * \param address access address.
 158  * \return pointer to the page structure.
 159  *
 160  * Get the the mapping, find the real physical page to map, get the page, and
 161  * return it.
 162  */
 163 static __inline__ struct page *drm_do_vm_shm_nopage(struct vm_area_struct *vma,
 164                                                     unsigned long address)
 165 {
 166         drm_map_t *map = (drm_map_t *) vma->vm_private_data;
 167         unsigned long offset;
 168         unsigned long i;
 169         struct page *page;
 170
 171         if (address > vma->vm_end)
 172                 return NOPAGE_SIGBUS;   /* Disallow mremap */
 173         if (!map)
 174                 return NOPAGE_SIGBUS;   /* Nothing allocated */
 175
 176         offset = address - vma->vm_start;
 177         i = (unsigned long)map->handle + offset;
 178         page = (map->type == _DRM_CONSISTENT) ?
 179                 virt_to_page((void *)i) : vmalloc_to_page((void *)i);
 180         if (!page)
 181                 return NOPAGE_SIGBUS;
 182         get_page(page);
 183
 184         DRM_DEBUG("shm_nopage 0x%lx\n", address);
 185         return page;
 186 }
 187
 188 /**
 189  * \c close method for shared virtual memory.
 190  *
 191  * \param vma virtual memory area.
 192  *
 193  * Deletes map information if we are the last
 194  * person to close a mapping and it's not in the global maplist.
 195  */
 196 static void drm_vm_shm_close(struct vm_area_struct *vma)
 197 {
 198         drm_file_t *priv = vma->vm_file->private_data;
 199         drm_device_t *dev = priv->head->dev;
 200         drm_vma_entry_t *pt, *prev, *next;
 201         drm_map_t *map;
 202         drm_map_list_t *r_list;
 203         struct list_head *list;
 204         int found_maps = 0;
 205
 206         DRM_DEBUG("0x%08lx,0x%08lx\n",
 207                   vma->vm_start, vma->vm_end - vma->vm_start);
 208         atomic_dec(&dev->vma_count);
 209
 210         map = vma->vm_private_data;
 211
 212         mutex_lock(&dev->struct_mutex);
 213         for (pt = dev->vmalist, prev = NULL; pt; pt = next) {
 214                 next = pt->next;
 215                 if (pt->vma->vm_private_data == map)
 216                         found_maps++;
 217                 if (pt->vma == vma) {
 218                         if (prev) {
 219                                 prev->next = pt->next;
 220                         } else {
 221                                 dev->vmalist = pt->next;
 222                         }
 223                         drm_free(pt, sizeof(*pt), DRM_MEM_VMAS);
 224                 } else {
 225                         prev = pt;
 226                 }
 227         }
 228         /* We were the only map that was found */
 229         if (found_maps == 1 && map->flags & _DRM_REMOVABLE) {
 230                 /* Check to see if we are in the maplist, if we are not, then
 231                  * we delete this mappings information.
 232                  */
 233                 found_maps = 0;
 234                 list = &dev->maplist->head;
 235                 list_for_each(list, &dev->maplist->head) {
 236                         r_list = list_entry(list, drm_map_list_t, head);
 237                         if (r_list->map == map)
 238                                 found_maps++;
 239                 }
 240
 241                 if (!found_maps) {
 242                         drm_dma_handle_t dmah;
 243
 244                         switch (map->type) {
 245                         case _DRM_REGISTERS:
 246                         case _DRM_FRAME_BUFFER:
 247                                 if (drm_core_has_MTRR(dev) && map->mtrr >= 0) {
 248                                         int retcode;
 249                                         retcode = mtrr_del(map->mtrr,
 250                                                            map->offset,
 251                                                            map->size);
 252                                         DRM_DEBUG("mtrr_del = %d\n", retcode);
 253                                 }
 254                                 iounmap(map->handle);
 255                                 break;
 256                         case _DRM_SHM:
 257                                 vfree(map->handle);
 258                                 break;
 259                         case _DRM_AGP:
 260                         case _DRM_SCATTER_GATHER:
 261                                 break;
 262                         case _DRM_CONSISTENT:
 263                                 dmah.vaddr = map->handle;
 264                                 dmah.busaddr = map->offset;
 265                                 dmah.size = map->size;
 266                                 __drm_pci_free(dev, &dmah);
 267                                 break;
 268                         }
 269                         drm_free(map, sizeof(*map), DRM_MEM_MAPS);
 270                 }
 271         }
 272         mutex_unlock(&dev->struct_mutex);
 273 }
 274
 275 /**
 276  * \c nopage method for DMA virtual memory.
 277  *
 278  * \param vma virtual memory area.
 279  * \param address access address.
 280  * \return pointer to the page structure.
 281  *
 282  * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
 283  */
 284 static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
 285                                                     unsigned long address)
 286 {
 287         drm_file_t *priv = vma->vm_file->private_data;
 288         drm_device_t *dev = priv->head->dev;
 289         drm_device_dma_t *dma = dev->dma;
 290         unsigned long offset;
 291         unsigned long page_nr;
 292         struct page *page;
 293
 294         if (!dma)
 295                 return NOPAGE_SIGBUS;   /* Error */
 296         if (address > vma->vm_end)
 297                 return NOPAGE_SIGBUS;   /* Disallow mremap */
 298         if (!dma->pagelist)
 299                 return NOPAGE_SIGBUS;   /* Nothing allocated */
 300
 301         offset = address - vma->vm_start;       /* vm_[pg]off[set] should be 0 */
 302         page_nr = offset >> PAGE_SHIFT;
 303         page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK))));
 304
 305         get_page(page);
 306
 307         DRM_DEBUG("dma_nopage 0x%lx (page %lu)\n", address, page_nr);
 308         return page;
 309 }
 310
 311 /**
 312  * \c nopage method for scatter-gather virtual memory.
 313  *
 314  * \param vma virtual memory area.
 315  * \param address access address.
 316  * \return pointer to the page structure.
 317  *
 318  * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
 319  */
 320 static __inline__ struct page *drm_do_vm_sg_nopage(struct vm_area_struct *vma,
 321                                                    unsigned long address)
 322 {
 323         drm_map_t *map = (drm_map_t *) vma->vm_private_data;
 324         drm_file_t *priv = vma->vm_file->private_data;
 325         drm_device_t *dev = priv->head->dev;
 326         drm_sg_mem_t *entry = dev->sg;
 327         unsigned long offset;
 328         unsigned long map_offset;
 329         unsigned long page_offset;
 330         struct page *page;
 331
 332         if (!entry)
 333                 return NOPAGE_SIGBUS;   /* Error */
 334         if (address > vma->vm_end)
 335                 return NOPAGE_SIGBUS;   /* Disallow mremap */
 336         if (!entry->pagelist)
 337                 return NOPAGE_SIGBUS;   /* Nothing allocated */
 338
 339         offset = address - vma->vm_start;
 340         map_offset = map->offset - (unsigned long)dev->sg->virtual;
 341         page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
 342         page = entry->pagelist[page_offset];
 343         get_page(page);
 344
 345         return page;
 346 }
 347
 348 static struct page *drm_vm_nopage(struct vm_area_struct *vma,
 349                                   unsigned long address, int *type)
 350 {
 351         if (type)
 352                 *type = VM_FAULT_MINOR;
 353         return drm_do_vm_nopage(vma, address);
 354 }
 355
 356 static struct page *drm_vm_shm_nopage(struct vm_area_struct *vma,
 357                                       unsigned long address, int *type)
 358 {
 359         if (type)
 360                 *type = VM_FAULT_MINOR;
 361         return drm_do_vm_shm_nopage(vma, address);
 362 }
 363
 364 static struct page *drm_vm_dma_nopage(struct vm_area_struct *vma,
 365                                       unsigned long address, int *type)
 366 {
 367         if (type)
 368                 *type = VM_FAULT_MINOR;
 369         return drm_do_vm_dma_nopage(vma, address);
 370 }
 371
 372 static struct page *drm_vm_sg_nopage(struct vm_area_struct *vma,
 373                                      unsigned long address, int *type)
 374 {
 375         if (type)
 376                 *type = VM_FAULT_MINOR;
 377         return drm_do_vm_sg_nopage(vma, address);
 378 }
 379
 380 /** AGP virtual memory operations */
 381 static struct vm_operations_struct drm_vm_ops = {
 382         .nopage = drm_vm_nopage,
 383         .open = drm_vm_open,
 384         .close = drm_vm_close,
 385 };
 386
 387 /** Shared virtual memory operations */
 388 static struct vm_operations_struct drm_vm_shm_ops = {
 389         .nopage = drm_vm_shm_nopage,
 390         .open = drm_vm_open,
 391         .close = drm_vm_shm_close,
 392 };
 393
 394 /** DMA virtual memory operations */
 395 static struct vm_operations_struct drm_vm_dma_ops = {
 396         .nopage = drm_vm_dma_nopage,
 397         .open = drm_vm_open,
 398         .close = drm_vm_close,
 399 };
 400
 401 /** Scatter-gather virtual memory operations */
 402 static struct vm_operations_struct drm_vm_sg_ops = {
 403         .nopage = drm_vm_sg_nopage,
 404         .open = drm_vm_open,
 405         .close = drm_vm_close,
 406 };
 407
 408 /**
 409  * \c open method for shared virtual memory.
 410  *
 411  * \param vma virtual memory area.
 412  *
 413  * Create a new drm_vma_entry structure as the \p vma private data entry and
 414  * add it to drm_device::vmalist.
 415  */
 416 static void drm_vm_open(struct vm_area_struct *vma)
 417 {
 418         drm_file_t *priv = vma->vm_file->private_data;
 419         drm_device_t *dev = priv->head->dev;
 420         drm_vma_entry_t *vma_entry;
 421
 422         DRM_DEBUG("0x%08lx,0x%08lx\n",
 423                   vma->vm_start, vma->vm_end - vma->vm_start);
 424         atomic_inc(&dev->vma_count);
 425
 426         vma_entry = drm_alloc(sizeof(*vma_entry), DRM_MEM_VMAS);
 427         if (vma_entry) {
 428                 mutex_lock(&dev->struct_mutex);
 429                 vma_entry->vma = vma;
 430                 vma_entry->next = dev->vmalist;
 431                 vma_entry->pid = current->pid;
 432                 dev->vmalist = vma_entry;
 433                 mutex_unlock(&dev->struct_mutex);
 434         }
 435 }
 436
 437 /**
 438  * \c close method for all virtual memory types.
 439  *
 440  * \param vma virtual memory area.
 441  *
 442  * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
 443  * free it.
 444  */
 445 static void drm_vm_close(struct vm_area_struct *vma)
 446 {
 447         drm_file_t *priv = vma->vm_file->private_data;
 448         drm_device_t *dev = priv->head->dev;
 449         drm_vma_entry_t *pt, *prev;
 450
 451         DRM_DEBUG("0x%08lx,0x%08lx\n",
 452                   vma->vm_start, vma->vm_end - vma->vm_start);
 453         atomic_dec(&dev->vma_count);
 454
 455         mutex_lock(&dev->struct_mutex);
 456         for (pt = dev->vmalist, prev = NULL; pt; prev = pt, pt = pt->next) {
 457                 if (pt->vma == vma) {
 458                         if (prev) {
 459                                 prev->next = pt->next;
 460                         } else {
 461                                 dev->vmalist = pt->next;
 462                         }
 463                         drm_free(pt, sizeof(*pt), DRM_MEM_VMAS);
 464                         break;
 465                 }
 466         }
 467         mutex_unlock(&dev->struct_mutex);
 468 }
 469
 470 /**
 471  * mmap DMA memory.
 472  *
 473  * \param filp file pointer.
 474  * \param vma virtual memory area.
 475  * \return zero on success or a negative number on failure.
 476  *
 477  * Sets the virtual memory area operations structure to vm_dma_ops, the file
 478  * pointer, and calls vm_open().
 479  */
 480 static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
 481 {
 482         drm_file_t *priv = filp->private_data;
 483         drm_device_t *dev;
 484         drm_device_dma_t *dma;
 485         unsigned long length = vma->vm_end - vma->vm_start;
 486
 487         lock_kernel();
 488         dev = priv->head->dev;
 489         dma = dev->dma;
 490         DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
 491                   vma->vm_start, vma->vm_end, vma->vm_pgoff);
 492
 493         /* Length must match exact page count */
 494         if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
 495                 unlock_kernel();
 496                 return -EINVAL;
 497         }
 498         unlock_kernel();
 499
 500         if (!capable(CAP_SYS_ADMIN) &&
 501             (dma->flags & _DRM_DMA_USE_PCI_RO)) {
 502                 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
 503 #if defined(__i386__) || defined(__x86_64__)
 504                 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
 505 #else
 506                 /* Ye gads this is ugly.  With more thought
 507                    we could move this up higher and use
 508                    `protection_map' instead.  */
 509                 vma->vm_page_prot =
 510                     __pgprot(pte_val
 511                              (pte_wrprotect
 512                               (__pte(pgprot_val(vma->vm_page_prot)))));
 513 #endif
 514         }
 515
 516         vma->vm_ops = &drm_vm_dma_ops;
 517
 518         vma->vm_flags |= VM_RESERVED;   /* Don't swap */
 519
 520         vma->vm_file = filp;    /* Needed for drm_vm_open() */
 521         drm_vm_open(vma);
 522         return 0;
 523 }
 524
 525 unsigned long drm_core_get_map_ofs(drm_map_t * map)
 526 {
 527         return map->offset;
 528 }
 529
 530 EXPORT_SYMBOL(drm_core_get_map_ofs);
 531
 532 unsigned long drm_core_get_reg_ofs(struct drm_device *dev)
 533 {
 534 #ifdef __alpha__
 535         return dev->hose->dense_mem_base - dev->hose->mem_space->start;
 536 #else
 537         return 0;
 538 #endif
 539 }
 540
 541 EXPORT_SYMBOL(drm_core_get_reg_ofs);
 542
 543 /**
 544  * mmap DMA memory.
 545  *
 546  * \param filp file pointer.
 547  * \param vma virtual memory area.
 548  * \return zero on success or a negative number on failure.
 549  *
 550  * If the virtual memory area has no offset associated with it then it's a DMA
 551  * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
 552  * checks that the restricted flag is not set, sets the virtual memory operations
 553  * according to the mapping type and remaps the pages. Finally sets the file
 554  * pointer and calls vm_open().
 555  */
 556 int drm_mmap(struct file *filp, struct vm_area_struct *vma)
 557 {
 558         drm_file_t *priv = filp->private_data;
 559         drm_device_t *dev = priv->head->dev;
 560         drm_map_t *map = NULL;
 561         unsigned long offset = 0;
 562         drm_hash_item_t *hash;
 563
 564         DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
 565                   vma->vm_start, vma->vm_end, vma->vm_pgoff);
 566
 567         if (!priv->authenticated)
 568                 return -EACCES;
 569
 570         /* We check for "dma". On Apple's UniNorth, it's valid to have
 571          * the AGP mapped at physical address 0
 572          * --BenH.
 573          */
 574         if (!vma->vm_pgoff
 575 #if __OS_HAS_AGP
 576             && (!dev->agp
 577                 || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
 578 #endif
 579             )
 580                 return drm_mmap_dma(filp, vma);
 581
 582         if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) {
 583                 DRM_ERROR("Could not find map\n");
 584                 return -EINVAL;
 585         }
 586
 587         map = drm_hash_entry(hash, drm_map_list_t, hash)->map;
 588         if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
 589                 return -EPERM;
 590
 591         /* Check for valid size. */
 592         if (map->size != vma->vm_end - vma->vm_start)
 593                 return -EINVAL;
 594
 595         if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
 596                 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
 597 #if defined(__i386__) || defined(__x86_64__)
 598                 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
 599 #else
 600                 /* Ye gads this is ugly.  With more thought
 601                    we could move this up higher and use
 602                    `protection_map' instead.  */
 603                 vma->vm_page_prot =
 604                     __pgprot(pte_val
 605                              (pte_wrprotect
 606                               (__pte(pgprot_val(vma->vm_page_prot)))));
 607 #endif
 608         }
 609
 610         switch (map->type) {
 611         case _DRM_AGP:
 612                 if (drm_core_has_AGP(dev) && dev->agp->cant_use_aperture) {
 613                         /*
 614                          * On some platforms we can't talk to bus dma address from the CPU, so for
 615                          * memory of type DRM_AGP, we'll deal with sorting out the real physical
 616                          * pages and mappings in nopage()
 617                          */
 618 #if defined(__powerpc__)
 619                         pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
 620 #endif
 621                         vma->vm_ops = &drm_vm_ops;
 622                         break;
 623                 }
 624                 /* fall through to _DRM_FRAME_BUFFER... */
 625         case _DRM_FRAME_BUFFER:
 626         case _DRM_REGISTERS:
 627                 offset = dev->driver->get_reg_ofs(dev);
 628                 vma->vm_flags |= VM_IO; /* not in core dump */
 629                 vma->vm_page_prot = drm_io_prot(map->type, vma);
 630 #ifdef __sparc__
 631                 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 632                 if (io_remap_pfn_range(vma, vma->vm_start,
 633                                        (map->offset + offset) >> PAGE_SHIFT,
 634                                        vma->vm_end - vma->vm_start,
 635                                        vma->vm_page_prot))
 636 #else
 637                 if (io_remap_pfn_range(vma, vma->vm_start,
 638                                        (map->offset + offset) >> PAGE_SHIFT,
 639                                        vma->vm_end - vma->vm_start,
 640                                        vma->vm_page_prot))
 641 #endif
 642                         return -EAGAIN;
 643                 DRM_DEBUG("   Type = %d; start = 0x%lx, end = 0x%lx,"
 644                           " offset = 0x%lx\n",
 645                           map->type,
 646                           vma->vm_start, vma->vm_end, map->offset + offset);
 647                 vma->vm_ops = &drm_vm_ops;
 648                 break;
 649         case _DRM_SHM:
 650         case _DRM_CONSISTENT:
 651                 /* Consistent memory is really like shared memory. It's only
 652                  * allocate in a different way */
 653                 vma->vm_ops = &drm_vm_shm_ops;
 654                 vma->vm_private_data = (void *)map;
 655                 /* Don't let this area swap.  Change when
 656                    DRM_KERNEL advisory is supported. */
 657                 vma->vm_flags |= VM_RESERVED;
 658                 break;
 659         case _DRM_SCATTER_GATHER:
 660                 vma->vm_ops = &drm_vm_sg_ops;
 661                 vma->vm_private_data = (void *)map;
 662                 vma->vm_flags |= VM_RESERVED;
 663                 break;
 664         default:
 665                 return -EINVAL; /* This should never happen. */
 666         }
 667         vma->vm_flags |= VM_RESERVED;   /* Don't swap */
 668
 669         vma->vm_file = filp;    /* Needed for drm_vm_open() */
 670         drm_vm_open(vma);
 671         return 0;
 672 }
 673
 674 EXPORT_SYMBOL(drm_mmap);