3 * Memory mapping for DRM
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
10 * Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com
12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
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:
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
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.
37 #include <linux/export.h>
39 #include <linux/efi.h>
40 #include <linux/slab.h>
43 static void drm_vm_open(struct vm_area_struct *vma);
44 static void drm_vm_close(struct vm_area_struct *vma);
46 static pgprot_t drm_io_prot(struct drm_local_map *map,
47 struct vm_area_struct *vma)
49 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
51 #if defined(__i386__) || defined(__x86_64__)
52 if (map->type == _DRM_REGISTERS && !(map->flags & _DRM_WRITE_COMBINING))
53 tmp = pgprot_noncached(tmp);
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 -
63 tmp = pgprot_writecombine(tmp);
65 tmp = pgprot_noncached(tmp);
66 #elif defined(__sparc__) || defined(__arm__) || defined(__mips__)
67 tmp = pgprot_noncached(tmp);
72 static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma)
74 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
76 #if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
77 tmp |= _PAGE_NO_CACHE;
83 * \c fault method for AGP virtual memory.
85 * \param vma virtual memory area.
86 * \param address access address.
87 * \return pointer to the page structure.
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.
93 static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
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;
107 if (!dev->agp || !dev->agp->cant_use_aperture)
110 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
113 r_list = drm_hash_entry(hash, struct drm_map_list, hash);
116 if (map && map->type == _DRM_AGP) {
118 * Using vm_pgoff as a selector forces us to use this unusual
121 resource_size_t offset = (unsigned long)vmf->virtual_address -
123 resource_size_t baddr = map->offset + offset;
124 struct drm_agp_mem *agpmem;
129 * Adjust to a bus-relative address
131 baddr -= dev->hose->mem_space->start;
135 * It's AGP memory - find the real physical page to map
137 list_for_each_entry(agpmem, &dev->agp->memory, head) {
138 if (agpmem->bound <= baddr &&
139 agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
143 if (&agpmem->head == &dev->agp->memory)
147 * Get the page, inc the use count, and return it
149 offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
150 page = agpmem->memory->pages[offset];
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,
163 return VM_FAULT_SIGBUS; /* Disallow mremap */
165 #else /* __OS_HAS_AGP */
166 static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
168 return VM_FAULT_SIGBUS;
170 #endif /* __OS_HAS_AGP */
173 * \c nopage method for shared virtual memory.
175 * \param vma virtual memory area.
176 * \param address access address.
177 * \return pointer to the page structure.
179 * Get the mapping, find the real physical page to map, get the page, and
182 static int drm_do_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
184 struct drm_local_map *map = vma->vm_private_data;
185 unsigned long offset;
190 return VM_FAULT_SIGBUS; /* Nothing allocated */
192 offset = (unsigned long)vmf->virtual_address - vma->vm_start;
193 i = (unsigned long)map->handle + offset;
194 page = vmalloc_to_page((void *)i);
196 return VM_FAULT_SIGBUS;
200 DRM_DEBUG("shm_fault 0x%lx\n", offset);
205 * \c close method for shared virtual memory.
207 * \param vma virtual memory area.
209 * Deletes map information if we are the last
210 * person to close a mapping and it's not in the global maplist.
212 static void drm_vm_shm_close(struct vm_area_struct *vma)
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;
221 DRM_DEBUG("0x%08lx,0x%08lx\n",
222 vma->vm_start, vma->vm_end - vma->vm_start);
223 atomic_dec(&dev->vma_count);
225 map = vma->vm_private_data;
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)
231 if (pt->vma == vma) {
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.
243 list_for_each_entry(r_list, &dev->maplist, head) {
244 if (r_list->map == map)
249 drm_dma_handle_t dmah;
253 case _DRM_FRAME_BUFFER:
254 arch_phys_wc_del(map->mtrr);
255 iounmap(map->handle);
261 case _DRM_SCATTER_GATHER:
263 case _DRM_CONSISTENT:
264 dmah.vaddr = map->handle;
265 dmah.busaddr = map->offset;
266 dmah.size = map->size;
267 __drm_pci_free(dev, &dmah);
273 mutex_unlock(&dev->struct_mutex);
277 * \c fault method for DMA virtual memory.
279 * \param vma virtual memory area.
280 * \param address access address.
281 * \return pointer to the page structure.
283 * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
285 static int drm_do_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
287 struct drm_file *priv = vma->vm_file->private_data;
288 struct drm_device *dev = priv->minor->dev;
289 struct drm_device_dma *dma = dev->dma;
290 unsigned long offset;
291 unsigned long page_nr;
295 return VM_FAULT_SIGBUS; /* Error */
297 return VM_FAULT_SIGBUS; /* Nothing allocated */
299 offset = (unsigned long)vmf->virtual_address - vma->vm_start; /* vm_[pg]off[set] should be 0 */
300 page_nr = offset >> PAGE_SHIFT; /* page_nr could just be vmf->pgoff */
301 page = virt_to_page((void *)dma->pagelist[page_nr]);
306 DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset, page_nr);
311 * \c fault method for scatter-gather virtual memory.
313 * \param vma virtual memory area.
314 * \param address access address.
315 * \return pointer to the page structure.
317 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
319 static int drm_do_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
321 struct drm_local_map *map = vma->vm_private_data;
322 struct drm_file *priv = vma->vm_file->private_data;
323 struct drm_device *dev = priv->minor->dev;
324 struct drm_sg_mem *entry = dev->sg;
325 unsigned long offset;
326 unsigned long map_offset;
327 unsigned long page_offset;
331 return VM_FAULT_SIGBUS; /* Error */
332 if (!entry->pagelist)
333 return VM_FAULT_SIGBUS; /* Nothing allocated */
335 offset = (unsigned long)vmf->virtual_address - vma->vm_start;
336 map_offset = map->offset - (unsigned long)dev->sg->virtual;
337 page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
338 page = entry->pagelist[page_offset];
345 static int drm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
347 return drm_do_vm_fault(vma, vmf);
350 static int drm_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
352 return drm_do_vm_shm_fault(vma, vmf);
355 static int drm_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
357 return drm_do_vm_dma_fault(vma, vmf);
360 static int drm_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
362 return drm_do_vm_sg_fault(vma, vmf);
365 /** AGP virtual memory operations */
366 static const struct vm_operations_struct drm_vm_ops = {
367 .fault = drm_vm_fault,
369 .close = drm_vm_close,
372 /** Shared virtual memory operations */
373 static const struct vm_operations_struct drm_vm_shm_ops = {
374 .fault = drm_vm_shm_fault,
376 .close = drm_vm_shm_close,
379 /** DMA virtual memory operations */
380 static const struct vm_operations_struct drm_vm_dma_ops = {
381 .fault = drm_vm_dma_fault,
383 .close = drm_vm_close,
386 /** Scatter-gather virtual memory operations */
387 static const struct vm_operations_struct drm_vm_sg_ops = {
388 .fault = drm_vm_sg_fault,
390 .close = drm_vm_close,
394 * \c open method for shared virtual memory.
396 * \param vma virtual memory area.
398 * Create a new drm_vma_entry structure as the \p vma private data entry and
399 * add it to drm_device::vmalist.
401 void drm_vm_open_locked(struct drm_device *dev,
402 struct vm_area_struct *vma)
404 struct drm_vma_entry *vma_entry;
406 DRM_DEBUG("0x%08lx,0x%08lx\n",
407 vma->vm_start, vma->vm_end - vma->vm_start);
408 atomic_inc(&dev->vma_count);
410 vma_entry = kmalloc(sizeof(*vma_entry), GFP_KERNEL);
412 vma_entry->vma = vma;
413 vma_entry->pid = current->pid;
414 list_add(&vma_entry->head, &dev->vmalist);
417 EXPORT_SYMBOL_GPL(drm_vm_open_locked);
419 static void drm_vm_open(struct vm_area_struct *vma)
421 struct drm_file *priv = vma->vm_file->private_data;
422 struct drm_device *dev = priv->minor->dev;
424 mutex_lock(&dev->struct_mutex);
425 drm_vm_open_locked(dev, vma);
426 mutex_unlock(&dev->struct_mutex);
429 void drm_vm_close_locked(struct drm_device *dev,
430 struct vm_area_struct *vma)
432 struct drm_vma_entry *pt, *temp;
434 DRM_DEBUG("0x%08lx,0x%08lx\n",
435 vma->vm_start, vma->vm_end - vma->vm_start);
436 atomic_dec(&dev->vma_count);
438 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
439 if (pt->vma == vma) {
448 * \c close method for all virtual memory types.
450 * \param vma virtual memory area.
452 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
455 static void drm_vm_close(struct vm_area_struct *vma)
457 struct drm_file *priv = vma->vm_file->private_data;
458 struct drm_device *dev = priv->minor->dev;
460 mutex_lock(&dev->struct_mutex);
461 drm_vm_close_locked(dev, vma);
462 mutex_unlock(&dev->struct_mutex);
468 * \param file_priv DRM file private.
469 * \param vma virtual memory area.
470 * \return zero on success or a negative number on failure.
472 * Sets the virtual memory area operations structure to vm_dma_ops, the file
473 * pointer, and calls vm_open().
475 static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
477 struct drm_file *priv = filp->private_data;
478 struct drm_device *dev;
479 struct drm_device_dma *dma;
480 unsigned long length = vma->vm_end - vma->vm_start;
482 dev = priv->minor->dev;
484 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
485 vma->vm_start, vma->vm_end, vma->vm_pgoff);
487 /* Length must match exact page count */
488 if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
492 if (!capable(CAP_SYS_ADMIN) &&
493 (dma->flags & _DRM_DMA_USE_PCI_RO)) {
494 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
495 #if defined(__i386__) || defined(__x86_64__)
496 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
498 /* Ye gads this is ugly. With more thought
499 we could move this up higher and use
500 `protection_map' instead. */
504 (__pte(pgprot_val(vma->vm_page_prot)))));
508 vma->vm_ops = &drm_vm_dma_ops;
510 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
512 drm_vm_open_locked(dev, vma);
516 static resource_size_t drm_core_get_reg_ofs(struct drm_device *dev)
519 return dev->hose->dense_mem_base;
528 * \param file_priv DRM file private.
529 * \param vma virtual memory area.
530 * \return zero on success or a negative number on failure.
532 * If the virtual memory area has no offset associated with it then it's a DMA
533 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
534 * checks that the restricted flag is not set, sets the virtual memory operations
535 * according to the mapping type and remaps the pages. Finally sets the file
536 * pointer and calls vm_open().
538 int drm_mmap_locked(struct file *filp, struct vm_area_struct *vma)
540 struct drm_file *priv = filp->private_data;
541 struct drm_device *dev = priv->minor->dev;
542 struct drm_local_map *map = NULL;
543 resource_size_t offset = 0;
544 struct drm_hash_item *hash;
546 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
547 vma->vm_start, vma->vm_end, vma->vm_pgoff);
549 if (!priv->authenticated)
552 /* We check for "dma". On Apple's UniNorth, it's valid to have
553 * the AGP mapped at physical address 0
559 || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
562 return drm_mmap_dma(filp, vma);
564 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) {
565 DRM_ERROR("Could not find map\n");
569 map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
570 if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
573 /* Check for valid size. */
574 if (map->size < vma->vm_end - vma->vm_start)
577 if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
578 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
579 #if defined(__i386__) || defined(__x86_64__)
580 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
582 /* Ye gads this is ugly. With more thought
583 we could move this up higher and use
584 `protection_map' instead. */
588 (__pte(pgprot_val(vma->vm_page_prot)))));
593 #if !defined(__arm__)
595 if (dev->agp && dev->agp->cant_use_aperture) {
597 * On some platforms we can't talk to bus dma address from the CPU, so for
598 * memory of type DRM_AGP, we'll deal with sorting out the real physical
599 * pages and mappings in fault()
601 #if defined(__powerpc__)
602 pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
604 vma->vm_ops = &drm_vm_ops;
607 /* fall through to _DRM_FRAME_BUFFER... */
609 case _DRM_FRAME_BUFFER:
611 offset = drm_core_get_reg_ofs(dev);
612 vma->vm_page_prot = drm_io_prot(map, vma);
613 if (io_remap_pfn_range(vma, vma->vm_start,
614 (map->offset + offset) >> PAGE_SHIFT,
615 vma->vm_end - vma->vm_start,
618 DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx,"
619 " offset = 0x%llx\n",
621 vma->vm_start, vma->vm_end, (unsigned long long)(map->offset + offset));
623 vma->vm_ops = &drm_vm_ops;
625 case _DRM_CONSISTENT:
626 /* Consistent memory is really like shared memory. But
627 * it's allocated in a different way, so avoid fault */
628 if (remap_pfn_range(vma, vma->vm_start,
629 page_to_pfn(virt_to_page(map->handle)),
630 vma->vm_end - vma->vm_start, vma->vm_page_prot))
632 vma->vm_page_prot = drm_dma_prot(map->type, vma);
633 /* fall through to _DRM_SHM */
635 vma->vm_ops = &drm_vm_shm_ops;
636 vma->vm_private_data = (void *)map;
638 case _DRM_SCATTER_GATHER:
639 vma->vm_ops = &drm_vm_sg_ops;
640 vma->vm_private_data = (void *)map;
641 vma->vm_page_prot = drm_dma_prot(map->type, vma);
644 return -EINVAL; /* This should never happen. */
646 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
648 drm_vm_open_locked(dev, vma);
652 int drm_mmap(struct file *filp, struct vm_area_struct *vma)
654 struct drm_file *priv = filp->private_data;
655 struct drm_device *dev = priv->minor->dev;
658 if (drm_device_is_unplugged(dev))
661 mutex_lock(&dev->struct_mutex);
662 ret = drm_mmap_locked(filp, vma);
663 mutex_unlock(&dev->struct_mutex);
667 EXPORT_SYMBOL(drm_mmap);