drivers/char/drm/drm_vm.c

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