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