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