git.oblomov.eu Git - linux-2.6/blob - 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 = (map->type == _DRM_CONSISTENT) ?
 152                 virt_to_page((void *)i) : vmalloc_to_page((void *)i);
 153         if (!page)
 154                 return NOPAGE_OOM;
 155         get_page(page);
 156
 157         DRM_DEBUG("shm_nopage 0x%lx\n", address);
 158         return page;
 159 }
 160
 161
 162 /**
 163  * \c close method for shared virtual memory.
 164  *
 165  * \param vma virtual memory area.
 166  *
 167  * Deletes map information if we are the last
 168  * person to close a mapping and it's not in the global maplist.
 169  */
 170 static void drm_vm_shm_close(struct vm_area_struct *vma)
 171 {
 172         drm_file_t      *priv   = vma->vm_file->private_data;
 173         drm_device_t    *dev    = priv->head->dev;
 174         drm_vma_entry_t *pt, *prev, *next;
 175         drm_map_t *map;
 176         drm_map_list_t *r_list;
 177         struct list_head *list;
 178         int found_maps = 0;
 179
 180         DRM_DEBUG("0x%08lx,0x%08lx\n",
 181                   vma->vm_start, vma->vm_end - vma->vm_start);
 182         atomic_dec(&dev->vma_count);
 183
 184         map = vma->vm_private_data;
 185
 186         down(&dev->struct_sem);
 187         for (pt = dev->vmalist, prev = NULL; pt; pt = next) {
 188                 next = pt->next;
 189                 if (pt->vma->vm_private_data == map) found_maps++;
 190                 if (pt->vma == vma) {
 191                         if (prev) {
 192                                 prev->next = pt->next;
 193                         } else {
 194                                 dev->vmalist = pt->next;
 195                         }
 196                         drm_free(pt, sizeof(*pt), DRM_MEM_VMAS);
 197                 } else {
 198                         prev = pt;
 199                 }
 200         }
 201         /* We were the only map that was found */
 202         if(found_maps == 1 &&
 203            map->flags & _DRM_REMOVABLE) {
 204                 /* Check to see if we are in the maplist, if we are not, then
 205                  * we delete this mappings information.
 206                  */
 207                 found_maps = 0;
 208                 list = &dev->maplist->head;
 209                 list_for_each(list, &dev->maplist->head) {
 210                         r_list = list_entry(list, drm_map_list_t, head);
 211                         if (r_list->map == map) found_maps++;
 212                 }
 213
 214                 if(!found_maps) {
 215                         drm_dma_handle_t dmah;
 216
 217                         switch (map->type) {
 218                         case _DRM_REGISTERS:
 219                         case _DRM_FRAME_BUFFER:
 220                                 if (drm_core_has_MTRR(dev) && map->mtrr >= 0) {
 221                                         int retcode;
 222                                         retcode = mtrr_del(map->mtrr,
 223                                                            map->offset,
 224                                                            map->size);
 225                                         DRM_DEBUG("mtrr_del = %d\n", retcode);
 226                                 }
 227                                 drm_ioremapfree(map->handle, map->size, dev);
 228                                 break;
 229                         case _DRM_SHM:
 230                                 vfree(map->handle);
 231                                 break;
 232                         case _DRM_AGP:
 233                         case _DRM_SCATTER_GATHER:
 234                                 break;
 235                         case _DRM_CONSISTENT:
 236                                 dmah.vaddr = map->handle;
 237                                 dmah.busaddr = map->offset;
 238                                 dmah.size = map->size;
 239                                 __drm_pci_free(dev, &dmah);
 240                                 break;
 241                         }
 242                         drm_free(map, sizeof(*map), DRM_MEM_MAPS);
 243                 }
 244         }
 245         up(&dev->struct_sem);
 246 }
 247
 248 /**
 249  * \c nopage method for DMA virtual memory.
 250  *
 251  * \param vma virtual memory area.
 252  * \param address access address.
 253  * \return pointer to the page structure.
 254  *
 255  * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
 256  */
 257 static __inline__ struct page *drm_do_vm_dma_nopage(struct vm_area_struct *vma,
 258                                                      unsigned long address)
 259 {
 260         drm_file_t       *priv   = vma->vm_file->private_data;
 261         drm_device_t     *dev    = priv->head->dev;
 262         drm_device_dma_t *dma    = dev->dma;
 263         unsigned long    offset;
 264         unsigned long    page_nr;
 265         struct page      *page;
 266
 267         if (!dma)                  return NOPAGE_SIGBUS; /* Error */
 268         if (address > vma->vm_end) return NOPAGE_SIGBUS; /* Disallow mremap */
 269         if (!dma->pagelist)        return NOPAGE_OOM ; /* Nothing allocated */
 270
 271         offset   = address - vma->vm_start; /* vm_[pg]off[set] should be 0 */
 272         page_nr  = offset >> PAGE_SHIFT;
 273         page = virt_to_page((dma->pagelist[page_nr] +
 274                              (offset & (~PAGE_MASK))));
 275
 276         get_page(page);
 277
 278         DRM_DEBUG("dma_nopage 0x%lx (page %lu)\n", address, page_nr);
 279         return page;
 280 }
 281
 282 /**
 283  * \c nopage method for scatter-gather virtual memory.
 284  *
 285  * \param vma virtual memory area.
 286  * \param address access address.
 287  * \return pointer to the page structure.
 288  *
 289  * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
 290  */
 291 static __inline__ struct page *drm_do_vm_sg_nopage(struct vm_area_struct *vma,
 292                                                     unsigned long address)
 293 {
 294         drm_map_t        *map    = (drm_map_t *)vma->vm_private_data;
 295         drm_file_t *priv = vma->vm_file->private_data;
 296         drm_device_t *dev = priv->head->dev;
 297         drm_sg_mem_t *entry = dev->sg;
 298         unsigned long offset;
 299         unsigned long map_offset;
 300         unsigned long page_offset;
 301         struct page *page;
 302
 303         if (!entry)                return NOPAGE_SIGBUS; /* Error */
 304         if (address > vma->vm_end) return NOPAGE_SIGBUS; /* Disallow mremap */
 305         if (!entry->pagelist)      return NOPAGE_OOM ;  /* Nothing allocated */
 306
 307
 308         offset = address - vma->vm_start;
 309         map_offset = map->offset - (unsigned long)dev->sg->virtual;
 310         page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
 311         page = entry->pagelist[page_offset];
 312         get_page(page);
 313
 314         return page;
 315 }
 316
 317
 318 static struct page *drm_vm_nopage(struct vm_area_struct *vma,
 319                                    unsigned long address,
 320                                    int *type) {
 321         if (type) *type = VM_FAULT_MINOR;
 322         return drm_do_vm_nopage(vma, address);
 323 }
 324
 325 static struct page *drm_vm_shm_nopage(struct vm_area_struct *vma,
 326                                        unsigned long address,
 327                                        int *type) {
 328         if (type) *type = VM_FAULT_MINOR;
 329         return drm_do_vm_shm_nopage(vma, address);
 330 }
 331
 332 static struct page *drm_vm_dma_nopage(struct vm_area_struct *vma,
 333                                        unsigned long address,
 334                                        int *type) {
 335         if (type) *type = VM_FAULT_MINOR;
 336         return drm_do_vm_dma_nopage(vma, address);
 337 }
 338
 339 static struct page *drm_vm_sg_nopage(struct vm_area_struct *vma,
 340                                       unsigned long address,
 341                                       int *type) {
 342         if (type) *type = VM_FAULT_MINOR;
 343         return drm_do_vm_sg_nopage(vma, address);
 344 }
 345
 346 /** AGP virtual memory operations */
 347 static struct vm_operations_struct   drm_vm_ops = {
 348         .nopage = drm_vm_nopage,
 349         .open   = drm_vm_open,
 350         .close  = drm_vm_close,
 351 };
 352
 353 /** Shared virtual memory operations */
 354 static struct vm_operations_struct   drm_vm_shm_ops = {
 355         .nopage = drm_vm_shm_nopage,
 356         .open   = drm_vm_open,
 357         .close  = drm_vm_shm_close,
 358 };
 359
 360 /** DMA virtual memory operations */
 361 static struct vm_operations_struct   drm_vm_dma_ops = {
 362         .nopage = drm_vm_dma_nopage,
 363         .open   = drm_vm_open,
 364         .close  = drm_vm_close,
 365 };
 366
 367 /** Scatter-gather virtual memory operations */
 368 static struct vm_operations_struct   drm_vm_sg_ops = {
 369         .nopage = drm_vm_sg_nopage,
 370         .open   = drm_vm_open,
 371         .close  = drm_vm_close,
 372 };
 373
 374
 375 /**
 376  * \c open method for shared virtual memory.
 377  *
 378  * \param vma virtual memory area.
 379  *
 380  * Create a new drm_vma_entry structure as the \p vma private data entry and
 381  * add it to drm_device::vmalist.
 382  */
 383 static void drm_vm_open(struct vm_area_struct *vma)
 384 {
 385         drm_file_t      *priv   = vma->vm_file->private_data;
 386         drm_device_t    *dev    = priv->head->dev;
 387         drm_vma_entry_t *vma_entry;
 388
 389         DRM_DEBUG("0x%08lx,0x%08lx\n",
 390                   vma->vm_start, vma->vm_end - vma->vm_start);
 391         atomic_inc(&dev->vma_count);
 392
 393         vma_entry = drm_alloc(sizeof(*vma_entry), DRM_MEM_VMAS);
 394         if (vma_entry) {
 395                 down(&dev->struct_sem);
 396                 vma_entry->vma  = vma;
 397                 vma_entry->next = dev->vmalist;
 398                 vma_entry->pid  = current->pid;
 399                 dev->vmalist    = vma_entry;
 400                 up(&dev->struct_sem);
 401         }
 402 }
 403
 404 /**
 405  * \c close method for all virtual memory types.
 406  *
 407  * \param vma virtual memory area.
 408  *
 409  * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
 410  * free it.
 411  */
 412 static void drm_vm_close(struct vm_area_struct *vma)
 413 {
 414         drm_file_t      *priv   = vma->vm_file->private_data;
 415         drm_device_t    *dev    = priv->head->dev;
 416         drm_vma_entry_t *pt, *prev;
 417
 418         DRM_DEBUG("0x%08lx,0x%08lx\n",
 419                   vma->vm_start, vma->vm_end - vma->vm_start);
 420         atomic_dec(&dev->vma_count);
 421
 422         down(&dev->struct_sem);
 423         for (pt = dev->vmalist, prev = NULL; pt; prev = pt, pt = pt->next) {
 424                 if (pt->vma == vma) {
 425                         if (prev) {
 426                                 prev->next = pt->next;
 427                         } else {
 428                                 dev->vmalist = pt->next;
 429                         }
 430                         drm_free(pt, sizeof(*pt), DRM_MEM_VMAS);
 431                         break;
 432                 }
 433         }
 434         up(&dev->struct_sem);
 435 }
 436
 437 /**
 438  * mmap DMA memory.
 439  *
 440  * \param filp file pointer.
 441  * \param vma virtual memory area.
 442  * \return zero on success or a negative number on failure.
 443  *
 444  * Sets the virtual memory area operations structure to vm_dma_ops, the file
 445  * pointer, and calls vm_open().
 446  */
 447 static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
 448 {
 449         drm_file_t       *priv   = filp->private_data;
 450         drm_device_t     *dev;
 451         drm_device_dma_t *dma;
 452         unsigned long    length  = vma->vm_end - vma->vm_start;
 453
 454         lock_kernel();
 455         dev      = priv->head->dev;
 456         dma      = dev->dma;
 457         DRM_DEBUG("start = 0x%lx, end = 0x%lx, offset = 0x%lx\n",
 458                   vma->vm_start, vma->vm_end, VM_OFFSET(vma));
 459
 460                                 /* Length must match exact page count */
 461         if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
 462                 unlock_kernel();
 463                 return -EINVAL;
 464         }
 465         unlock_kernel();
 466
 467         vma->vm_ops   = &drm_vm_dma_ops;
 468
 469         vma->vm_flags |= VM_RESERVED; /* Don't swap */
 470
 471         vma->vm_file  =  filp;  /* Needed for drm_vm_open() */
 472         drm_vm_open(vma);
 473         return 0;
 474 }
 475
 476 unsigned long drm_core_get_map_ofs(drm_map_t *map)
 477 {
 478         return map->offset;
 479 }
 480 EXPORT_SYMBOL(drm_core_get_map_ofs);
 481
 482 unsigned long drm_core_get_reg_ofs(struct drm_device *dev)
 483 {
 484 #ifdef __alpha__
 485         return dev->hose->dense_mem_base - dev->hose->mem_space->start;
 486 #else
 487         return 0;
 488 #endif
 489 }
 490 EXPORT_SYMBOL(drm_core_get_reg_ofs);
 491
 492 /**
 493  * mmap DMA memory.
 494  *
 495  * \param filp file pointer.
 496  * \param vma virtual memory area.
 497  * \return zero on success or a negative number on failure.
 498  *
 499  * If the virtual memory area has no offset associated with it then it's a DMA
 500  * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
 501  * checks that the restricted flag is not set, sets the virtual memory operations
 502  * according to the mapping type and remaps the pages. Finally sets the file
 503  * pointer and calls vm_open().
 504  */
 505 int drm_mmap(struct file *filp, struct vm_area_struct *vma)
 506 {
 507         drm_file_t      *priv   = filp->private_data;
 508         drm_device_t    *dev    = priv->head->dev;
 509         drm_map_t       *map    = NULL;
 510         drm_map_list_t  *r_list;
 511         unsigned long   offset  = 0;
 512         struct list_head *list;
 513
 514         DRM_DEBUG("start = 0x%lx, end = 0x%lx, offset = 0x%lx\n",
 515                   vma->vm_start, vma->vm_end, VM_OFFSET(vma));
 516
 517         if ( !priv->authenticated ) return -EACCES;
 518
 519         /* We check for "dma". On Apple's UniNorth, it's valid to have
 520          * the AGP mapped at physical address 0
 521          * --BenH.
 522          */
 523         if (!VM_OFFSET(vma)
 524 #if __OS_HAS_AGP
 525             && (!dev->agp || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
 526 #endif
 527             )
 528                 return drm_mmap_dma(filp, vma);
 529
 530                                 /* A sequential search of a linked list is
 531                                    fine here because: 1) there will only be
 532                                    about 5-10 entries in the list and, 2) a
 533                                    DRI client only has to do this mapping
 534                                    once, so it doesn't have to be optimized
 535                                    for performance, even if the list was a
 536                                    bit longer. */
 537         list_for_each(list, &dev->maplist->head) {
 538
 539                 r_list = list_entry(list, drm_map_list_t, head);
 540                 map = r_list->map;
 541                 if (!map) continue;
 542                 if (r_list->user_token == VM_OFFSET(vma))
 543                         break;
 544         }
 545
 546         if (!map || ((map->flags&_DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
 547                 return -EPERM;
 548
 549                                 /* Check for valid size. */
 550         if (map->size != vma->vm_end - vma->vm_start) return -EINVAL;
 551
 552         if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
 553                 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
 554 #if defined(__i386__) || defined(__x86_64__)
 555                 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
 556 #else
 557                                 /* Ye gads this is ugly.  With more thought
 558                                    we could move this up higher and use
 559                                    `protection_map' instead.  */
 560                 vma->vm_page_prot = __pgprot(pte_val(pte_wrprotect(
 561                         __pte(pgprot_val(vma->vm_page_prot)))));
 562 #endif
 563         }
 564
 565         switch (map->type) {
 566         case _DRM_AGP:
 567           if (drm_core_has_AGP(dev) && dev->agp->cant_use_aperture) {
 568                 /*
 569                  * On some platforms we can't talk to bus dma address from the CPU, so for
 570                  * memory of type DRM_AGP, we'll deal with sorting out the real physical
 571                  * pages and mappings in nopage()
 572                  */
 573 #if defined(__powerpc__)
 574                 pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
 575 #endif
 576                 vma->vm_ops = &drm_vm_ops;
 577                 break;
 578           }
 579                 /* fall through to _DRM_FRAME_BUFFER... */
 580         case _DRM_FRAME_BUFFER:
 581         case _DRM_REGISTERS:
 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;
 589                 if (map->type == _DRM_REGISTERS)
 590                         pgprot_val(vma->vm_page_prot) |= _PAGE_GUARDED;
 591 #endif
 592                 vma->vm_flags |= VM_IO; /* not in core dump */
 593 #if defined(__ia64__)
 594                 if (efi_range_is_wc(vma->vm_start, vma->vm_end -
 595                                     vma->vm_start))
 596                         vma->vm_page_prot =
 597                                 pgprot_writecombine(vma->vm_page_prot);
 598                 else
 599                         vma->vm_page_prot =
 600                                 pgprot_noncached(vma->vm_page_prot);
 601 #endif
 602                 offset = dev->driver->get_reg_ofs(dev);
 603 #ifdef __sparc__
 604                 if (io_remap_pfn_range(DRM_RPR_ARG(vma) vma->vm_start,
 605                                         (map->offset + offset) >> PAGE_SHIFT,
 606                                         vma->vm_end - vma->vm_start,
 607                                         vma->vm_page_prot))
 608 #else
 609                 if (io_remap_pfn_range(vma, vma->vm_start,
 610                                      (map->offset + offset) >> PAGE_SHIFT,
 611                                      vma->vm_end - vma->vm_start,
 612                                      vma->vm_page_prot))
 613 #endif
 614                                 return -EAGAIN;
 615                 DRM_DEBUG("   Type = %d; start = 0x%lx, end = 0x%lx,"
 616                           " offset = 0x%lx\n",
 617                           map->type,
 618                           vma->vm_start, vma->vm_end, map->offset + offset);
 619                 vma->vm_ops = &drm_vm_ops;
 620                 break;
 621         case _DRM_SHM:
 622         case _DRM_CONSISTENT:
 623                 /* Consistent memory is really like shared memory. It's only
 624                  * allocate in a different way */
 625                 vma->vm_ops = &drm_vm_shm_ops;
 626                 vma->vm_private_data = (void *)map;
 627                                 /* Don't let this area swap.  Change when
 628                                    DRM_KERNEL advisory is supported. */
 629                 vma->vm_flags |= VM_RESERVED;
 630                 break;
 631         case _DRM_SCATTER_GATHER:
 632                 vma->vm_ops = &drm_vm_sg_ops;
 633                 vma->vm_private_data = (void *)map;
 634                 vma->vm_flags |= VM_RESERVED;
 635                 break;
 636         default:
 637                 return -EINVAL; /* This should never happen. */
 638         }
 639         vma->vm_flags |= VM_RESERVED; /* Don't swap */
 640
 641         vma->vm_file  =  filp;  /* Needed for drm_vm_open() */
 642         drm_vm_open(vma);
 643         return 0;
 644 }
 645 EXPORT_SYMBOL(drm_mmap);