drm_vm.c revision fdcdec06a3027ab227b1780c353acece65c8e970
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 <drm/drmP.h> 37#include <linux/export.h> 38#if defined(__ia64__) 39#include <linux/efi.h> 40#include <linux/slab.h> 41#endif 42 43static void drm_vm_open(struct vm_area_struct *vma); 44static void drm_vm_close(struct vm_area_struct *vma); 45 46static pgprot_t drm_io_prot(struct drm_local_map *map, 47 struct vm_area_struct *vma) 48{ 49 pgprot_t tmp = vm_get_page_prot(vma->vm_flags); 50 51#if defined(__i386__) || defined(__x86_64__) 52 if (map->type == _DRM_REGISTERS && !(map->flags & _DRM_WRITE_COMBINING)) 53 tmp = pgprot_noncached(tmp); 54 else 55 tmp = pgprot_writecombine(tmp); 56#elif defined(__powerpc__) 57 pgprot_val(tmp) |= _PAGE_NO_CACHE; 58 if (map->type == _DRM_REGISTERS) 59 pgprot_val(tmp) |= _PAGE_GUARDED; 60#elif defined(__ia64__) 61 if (efi_range_is_wc(vma->vm_start, vma->vm_end - 62 vma->vm_start)) 63 tmp = pgprot_writecombine(tmp); 64 else 65 tmp = pgprot_noncached(tmp); 66#elif defined(__sparc__) || defined(__arm__) || defined(__mips__) 67 tmp = pgprot_noncached(tmp); 68#endif 69 return tmp; 70} 71 72static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma) 73{ 74 pgprot_t tmp = vm_get_page_prot(vma->vm_flags); 75 76#if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE) 77 tmp |= _PAGE_NO_CACHE; 78#endif 79 return tmp; 80} 81 82/** 83 * \c fault method for AGP virtual memory. 84 * 85 * \param vma virtual memory area. 86 * \param address access address. 87 * \return pointer to the page structure. 88 * 89 * Find the right map and if it's AGP memory find the real physical page to 90 * map, get the page, increment the use count and return it. 91 */ 92#if __OS_HAS_AGP 93static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 94{ 95 struct drm_file *priv = vma->vm_file->private_data; 96 struct drm_device *dev = priv->minor->dev; 97 struct drm_local_map *map = NULL; 98 struct drm_map_list *r_list; 99 struct drm_hash_item *hash; 100 101 /* 102 * Find the right map 103 */ 104 if (!drm_core_has_AGP(dev)) 105 goto vm_fault_error; 106 107 if (!dev->agp || !dev->agp->cant_use_aperture) 108 goto vm_fault_error; 109 110 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) 111 goto vm_fault_error; 112 113 r_list = drm_hash_entry(hash, struct drm_map_list, hash); 114 map = r_list->map; 115 116 if (map && map->type == _DRM_AGP) { 117 /* 118 * Using vm_pgoff as a selector forces us to use this unusual 119 * addressing scheme. 120 */ 121 resource_size_t offset = (unsigned long)vmf->virtual_address - 122 vma->vm_start; 123 resource_size_t baddr = map->offset + offset; 124 struct drm_agp_mem *agpmem; 125 struct page *page; 126 127#ifdef __alpha__ 128 /* 129 * Adjust to a bus-relative address 130 */ 131 baddr -= dev->hose->mem_space->start; 132#endif 133 134 /* 135 * It's AGP memory - find the real physical page to map 136 */ 137 list_for_each_entry(agpmem, &dev->agp->memory, head) { 138 if (agpmem->bound <= baddr && 139 agpmem->bound + agpmem->pages * PAGE_SIZE > baddr) 140 break; 141 } 142 143 if (&agpmem->head == &dev->agp->memory) 144 goto vm_fault_error; 145 146 /* 147 * Get the page, inc the use count, and return it 148 */ 149 offset = (baddr - agpmem->bound) >> PAGE_SHIFT; 150 page = agpmem->memory->pages[offset]; 151 get_page(page); 152 vmf->page = page; 153 154 DRM_DEBUG 155 ("baddr = 0x%llx page = 0x%p, offset = 0x%llx, count=%d\n", 156 (unsigned long long)baddr, 157 agpmem->memory->pages[offset], 158 (unsigned long long)offset, 159 page_count(page)); 160 return 0; 161 } 162vm_fault_error: 163 return VM_FAULT_SIGBUS; /* Disallow mremap */ 164} 165#else /* __OS_HAS_AGP */ 166static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 167{ 168 return VM_FAULT_SIGBUS; 169} 170#endif /* __OS_HAS_AGP */ 171 172/** 173 * \c nopage method for shared virtual memory. 174 * 175 * \param vma virtual memory area. 176 * \param address access address. 177 * \return pointer to the page structure. 178 * 179 * Get the mapping, find the real physical page to map, get the page, and 180 * return it. 181 */ 182static int drm_do_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 183{ 184 struct drm_local_map *map = vma->vm_private_data; 185 unsigned long offset; 186 unsigned long i; 187 struct page *page; 188 189 if (!map) 190 return VM_FAULT_SIGBUS; /* Nothing allocated */ 191 192 offset = (unsigned long)vmf->virtual_address - vma->vm_start; 193 i = (unsigned long)map->handle + offset; 194 page = vmalloc_to_page((void *)i); 195 if (!page) 196 return VM_FAULT_SIGBUS; 197 get_page(page); 198 vmf->page = page; 199 200 DRM_DEBUG("shm_fault 0x%lx\n", offset); 201 return 0; 202} 203 204/** 205 * \c close method for shared virtual memory. 206 * 207 * \param vma virtual memory area. 208 * 209 * Deletes map information if we are the last 210 * person to close a mapping and it's not in the global maplist. 211 */ 212static void drm_vm_shm_close(struct vm_area_struct *vma) 213{ 214 struct drm_file *priv = vma->vm_file->private_data; 215 struct drm_device *dev = priv->minor->dev; 216 struct drm_vma_entry *pt, *temp; 217 struct drm_local_map *map; 218 struct drm_map_list *r_list; 219 int found_maps = 0; 220 221 DRM_DEBUG("0x%08lx,0x%08lx\n", 222 vma->vm_start, vma->vm_end - vma->vm_start); 223 atomic_dec(&dev->vma_count); 224 225 map = vma->vm_private_data; 226 227 mutex_lock(&dev->struct_mutex); 228 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) { 229 if (pt->vma->vm_private_data == map) 230 found_maps++; 231 if (pt->vma == vma) { 232 list_del(&pt->head); 233 kfree(pt); 234 } 235 } 236 237 /* We were the only map that was found */ 238 if (found_maps == 1 && map->flags & _DRM_REMOVABLE) { 239 /* Check to see if we are in the maplist, if we are not, then 240 * we delete this mappings information. 241 */ 242 found_maps = 0; 243 list_for_each_entry(r_list, &dev->maplist, head) { 244 if (r_list->map == map) 245 found_maps++; 246 } 247 248 if (!found_maps) { 249 drm_dma_handle_t dmah; 250 251 switch (map->type) { 252 case _DRM_REGISTERS: 253 case _DRM_FRAME_BUFFER: 254 if (drm_core_has_MTRR(dev)) 255 arch_phys_wc_del(map->mtrr); 256 iounmap(map->handle); 257 break; 258 case _DRM_SHM: 259 vfree(map->handle); 260 break; 261 case _DRM_AGP: 262 case _DRM_SCATTER_GATHER: 263 break; 264 case _DRM_CONSISTENT: 265 dmah.vaddr = map->handle; 266 dmah.busaddr = map->offset; 267 dmah.size = map->size; 268 __drm_pci_free(dev, &dmah); 269 break; 270 case _DRM_GEM: 271 DRM_ERROR("tried to rmmap GEM object\n"); 272 break; 273 } 274 kfree(map); 275 } 276 } 277 mutex_unlock(&dev->struct_mutex); 278} 279 280/** 281 * \c fault method for DMA virtual memory. 282 * 283 * \param vma virtual memory area. 284 * \param address access address. 285 * \return pointer to the page structure. 286 * 287 * Determine the page number from the page offset and get it from drm_device_dma::pagelist. 288 */ 289static int drm_do_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 290{ 291 struct drm_file *priv = vma->vm_file->private_data; 292 struct drm_device *dev = priv->minor->dev; 293 struct drm_device_dma *dma = dev->dma; 294 unsigned long offset; 295 unsigned long page_nr; 296 struct page *page; 297 298 if (!dma) 299 return VM_FAULT_SIGBUS; /* Error */ 300 if (!dma->pagelist) 301 return VM_FAULT_SIGBUS; /* Nothing allocated */ 302 303 offset = (unsigned long)vmf->virtual_address - vma->vm_start; /* vm_[pg]off[set] should be 0 */ 304 page_nr = offset >> PAGE_SHIFT; /* page_nr could just be vmf->pgoff */ 305 page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK)))); 306 307 get_page(page); 308 vmf->page = page; 309 310 DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset, page_nr); 311 return 0; 312} 313 314/** 315 * \c fault method for scatter-gather virtual memory. 316 * 317 * \param vma virtual memory area. 318 * \param address access address. 319 * \return pointer to the page structure. 320 * 321 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist. 322 */ 323static int drm_do_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 324{ 325 struct drm_local_map *map = vma->vm_private_data; 326 struct drm_file *priv = vma->vm_file->private_data; 327 struct drm_device *dev = priv->minor->dev; 328 struct drm_sg_mem *entry = dev->sg; 329 unsigned long offset; 330 unsigned long map_offset; 331 unsigned long page_offset; 332 struct page *page; 333 334 if (!entry) 335 return VM_FAULT_SIGBUS; /* Error */ 336 if (!entry->pagelist) 337 return VM_FAULT_SIGBUS; /* Nothing allocated */ 338 339 offset = (unsigned long)vmf->virtual_address - vma->vm_start; 340 map_offset = map->offset - (unsigned long)dev->sg->virtual; 341 page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT); 342 page = entry->pagelist[page_offset]; 343 get_page(page); 344 vmf->page = page; 345 346 return 0; 347} 348 349static int drm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 350{ 351 return drm_do_vm_fault(vma, vmf); 352} 353 354static int drm_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 355{ 356 return drm_do_vm_shm_fault(vma, vmf); 357} 358 359static int drm_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 360{ 361 return drm_do_vm_dma_fault(vma, vmf); 362} 363 364static int drm_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf) 365{ 366 return drm_do_vm_sg_fault(vma, vmf); 367} 368 369/** AGP virtual memory operations */ 370static const struct vm_operations_struct drm_vm_ops = { 371 .fault = drm_vm_fault, 372 .open = drm_vm_open, 373 .close = drm_vm_close, 374}; 375 376/** Shared virtual memory operations */ 377static const struct vm_operations_struct drm_vm_shm_ops = { 378 .fault = drm_vm_shm_fault, 379 .open = drm_vm_open, 380 .close = drm_vm_shm_close, 381}; 382 383/** DMA virtual memory operations */ 384static const struct vm_operations_struct drm_vm_dma_ops = { 385 .fault = drm_vm_dma_fault, 386 .open = drm_vm_open, 387 .close = drm_vm_close, 388}; 389 390/** Scatter-gather virtual memory operations */ 391static const struct vm_operations_struct drm_vm_sg_ops = { 392 .fault = drm_vm_sg_fault, 393 .open = drm_vm_open, 394 .close = drm_vm_close, 395}; 396 397/** 398 * \c open method for shared virtual memory. 399 * 400 * \param vma virtual memory area. 401 * 402 * Create a new drm_vma_entry structure as the \p vma private data entry and 403 * add it to drm_device::vmalist. 404 */ 405void drm_vm_open_locked(struct drm_device *dev, 406 struct vm_area_struct *vma) 407{ 408 struct drm_vma_entry *vma_entry; 409 410 DRM_DEBUG("0x%08lx,0x%08lx\n", 411 vma->vm_start, vma->vm_end - vma->vm_start); 412 atomic_inc(&dev->vma_count); 413 414 vma_entry = kmalloc(sizeof(*vma_entry), GFP_KERNEL); 415 if (vma_entry) { 416 vma_entry->vma = vma; 417 vma_entry->pid = current->pid; 418 list_add(&vma_entry->head, &dev->vmalist); 419 } 420} 421EXPORT_SYMBOL_GPL(drm_vm_open_locked); 422 423static void drm_vm_open(struct vm_area_struct *vma) 424{ 425 struct drm_file *priv = vma->vm_file->private_data; 426 struct drm_device *dev = priv->minor->dev; 427 428 mutex_lock(&dev->struct_mutex); 429 drm_vm_open_locked(dev, vma); 430 mutex_unlock(&dev->struct_mutex); 431} 432 433void drm_vm_close_locked(struct drm_device *dev, 434 struct vm_area_struct *vma) 435{ 436 struct drm_vma_entry *pt, *temp; 437 438 DRM_DEBUG("0x%08lx,0x%08lx\n", 439 vma->vm_start, vma->vm_end - vma->vm_start); 440 atomic_dec(&dev->vma_count); 441 442 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) { 443 if (pt->vma == vma) { 444 list_del(&pt->head); 445 kfree(pt); 446 break; 447 } 448 } 449} 450 451/** 452 * \c close method for all virtual memory types. 453 * 454 * \param vma virtual memory area. 455 * 456 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and 457 * free it. 458 */ 459static void drm_vm_close(struct vm_area_struct *vma) 460{ 461 struct drm_file *priv = vma->vm_file->private_data; 462 struct drm_device *dev = priv->minor->dev; 463 464 mutex_lock(&dev->struct_mutex); 465 drm_vm_close_locked(dev, vma); 466 mutex_unlock(&dev->struct_mutex); 467} 468 469/** 470 * mmap DMA memory. 471 * 472 * \param file_priv DRM file private. 473 * \param vma virtual memory area. 474 * \return zero on success or a negative number on failure. 475 * 476 * Sets the virtual memory area operations structure to vm_dma_ops, the file 477 * pointer, and calls vm_open(). 478 */ 479static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma) 480{ 481 struct drm_file *priv = filp->private_data; 482 struct drm_device *dev; 483 struct drm_device_dma *dma; 484 unsigned long length = vma->vm_end - vma->vm_start; 485 486 dev = priv->minor->dev; 487 dma = dev->dma; 488 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n", 489 vma->vm_start, vma->vm_end, vma->vm_pgoff); 490 491 /* Length must match exact page count */ 492 if (!dma || (length >> PAGE_SHIFT) != dma->page_count) { 493 return -EINVAL; 494 } 495 496 if (!capable(CAP_SYS_ADMIN) && 497 (dma->flags & _DRM_DMA_USE_PCI_RO)) { 498 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE); 499#if defined(__i386__) || defined(__x86_64__) 500 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW; 501#else 502 /* Ye gads this is ugly. With more thought 503 we could move this up higher and use 504 `protection_map' instead. */ 505 vma->vm_page_prot = 506 __pgprot(pte_val 507 (pte_wrprotect 508 (__pte(pgprot_val(vma->vm_page_prot))))); 509#endif 510 } 511 512 vma->vm_ops = &drm_vm_dma_ops; 513 514 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; 515 516 drm_vm_open_locked(dev, vma); 517 return 0; 518} 519 520static resource_size_t drm_core_get_reg_ofs(struct drm_device *dev) 521{ 522#ifdef __alpha__ 523 return dev->hose->dense_mem_base; 524#else 525 return 0; 526#endif 527} 528 529/** 530 * mmap DMA memory. 531 * 532 * \param file_priv DRM file private. 533 * \param vma virtual memory area. 534 * \return zero on success or a negative number on failure. 535 * 536 * If the virtual memory area has no offset associated with it then it's a DMA 537 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist, 538 * checks that the restricted flag is not set, sets the virtual memory operations 539 * according to the mapping type and remaps the pages. Finally sets the file 540 * pointer and calls vm_open(). 541 */ 542int drm_mmap_locked(struct file *filp, struct vm_area_struct *vma) 543{ 544 struct drm_file *priv = filp->private_data; 545 struct drm_device *dev = priv->minor->dev; 546 struct drm_local_map *map = NULL; 547 resource_size_t offset = 0; 548 struct drm_hash_item *hash; 549 550 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n", 551 vma->vm_start, vma->vm_end, vma->vm_pgoff); 552 553 if (!priv->authenticated) 554 return -EACCES; 555 556 /* We check for "dma". On Apple's UniNorth, it's valid to have 557 * the AGP mapped at physical address 0 558 * --BenH. 559 */ 560 if (!vma->vm_pgoff 561#if __OS_HAS_AGP 562 && (!dev->agp 563 || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE) 564#endif 565 ) 566 return drm_mmap_dma(filp, vma); 567 568 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) { 569 DRM_ERROR("Could not find map\n"); 570 return -EINVAL; 571 } 572 573 map = drm_hash_entry(hash, struct drm_map_list, hash)->map; 574 if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) 575 return -EPERM; 576 577 /* Check for valid size. */ 578 if (map->size < vma->vm_end - vma->vm_start) 579 return -EINVAL; 580 581 if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) { 582 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE); 583#if defined(__i386__) || defined(__x86_64__) 584 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW; 585#else 586 /* Ye gads this is ugly. With more thought 587 we could move this up higher and use 588 `protection_map' instead. */ 589 vma->vm_page_prot = 590 __pgprot(pte_val 591 (pte_wrprotect 592 (__pte(pgprot_val(vma->vm_page_prot))))); 593#endif 594 } 595 596 switch (map->type) { 597#if !defined(__arm__) 598 case _DRM_AGP: 599 if (drm_core_has_AGP(dev) && dev->agp->cant_use_aperture) { 600 /* 601 * On some platforms we can't talk to bus dma address from the CPU, so for 602 * memory of type DRM_AGP, we'll deal with sorting out the real physical 603 * pages and mappings in fault() 604 */ 605#if defined(__powerpc__) 606 pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE; 607#endif 608 vma->vm_ops = &drm_vm_ops; 609 break; 610 } 611 /* fall through to _DRM_FRAME_BUFFER... */ 612#endif 613 case _DRM_FRAME_BUFFER: 614 case _DRM_REGISTERS: 615 offset = drm_core_get_reg_ofs(dev); 616 vma->vm_page_prot = drm_io_prot(map, vma); 617 if (io_remap_pfn_range(vma, vma->vm_start, 618 (map->offset + offset) >> PAGE_SHIFT, 619 vma->vm_end - vma->vm_start, 620 vma->vm_page_prot)) 621 return -EAGAIN; 622 DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx," 623 " offset = 0x%llx\n", 624 map->type, 625 vma->vm_start, vma->vm_end, (unsigned long long)(map->offset + offset)); 626 627 vma->vm_ops = &drm_vm_ops; 628 break; 629 case _DRM_CONSISTENT: 630 /* Consistent memory is really like shared memory. But 631 * it's allocated in a different way, so avoid fault */ 632 if (remap_pfn_range(vma, vma->vm_start, 633 page_to_pfn(virt_to_page(map->handle)), 634 vma->vm_end - vma->vm_start, vma->vm_page_prot)) 635 return -EAGAIN; 636 vma->vm_page_prot = drm_dma_prot(map->type, vma); 637 /* fall through to _DRM_SHM */ 638 case _DRM_SHM: 639 vma->vm_ops = &drm_vm_shm_ops; 640 vma->vm_private_data = (void *)map; 641 break; 642 case _DRM_SCATTER_GATHER: 643 vma->vm_ops = &drm_vm_sg_ops; 644 vma->vm_private_data = (void *)map; 645 vma->vm_page_prot = drm_dma_prot(map->type, vma); 646 break; 647 default: 648 return -EINVAL; /* This should never happen. */ 649 } 650 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; 651 652 drm_vm_open_locked(dev, vma); 653 return 0; 654} 655 656int drm_mmap(struct file *filp, struct vm_area_struct *vma) 657{ 658 struct drm_file *priv = filp->private_data; 659 struct drm_device *dev = priv->minor->dev; 660 int ret; 661 662 if (drm_device_is_unplugged(dev)) 663 return -ENODEV; 664 665 mutex_lock(&dev->struct_mutex); 666 ret = drm_mmap_locked(filp, vma); 667 mutex_unlock(&dev->struct_mutex); 668 669 return ret; 670} 671EXPORT_SYMBOL(drm_mmap); 672