3 * Memory mapping for DRM
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
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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>
38 #include <linux/seq_file.h>
40 #include <linux/efi.h>
41 #include <linux/slab.h>
43 #include <linux/mem_encrypt.h>
44 #include <asm/pgtable.h>
45 #include "drm_internal.h"
46 #include "drm_legacy.h"
48 struct drm_vma_entry {
49 struct list_head head;
50 struct vm_area_struct *vma;
54 static void drm_vm_open(struct vm_area_struct *vma);
55 static void drm_vm_close(struct vm_area_struct *vma);
57 static pgprot_t drm_io_prot(struct drm_local_map *map,
58 struct vm_area_struct *vma)
60 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
62 /* We don't want graphics memory to be mapped encrypted */
63 tmp = pgprot_decrypted(tmp);
65 #if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__)
66 if (map->type == _DRM_REGISTERS && !(map->flags & _DRM_WRITE_COMBINING))
67 tmp = pgprot_noncached(tmp);
69 tmp = pgprot_writecombine(tmp);
70 #elif defined(__ia64__)
71 if (efi_range_is_wc(vma->vm_start, vma->vm_end -
73 tmp = pgprot_writecombine(tmp);
75 tmp = pgprot_noncached(tmp);
76 #elif defined(__sparc__) || defined(__arm__) || defined(__mips__)
77 tmp = pgprot_noncached(tmp);
82 static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma)
84 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
86 #if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
87 tmp = pgprot_noncached_wc(tmp);
93 * \c fault method for AGP virtual memory.
95 * \param vma virtual memory area.
96 * \param address access address.
97 * \return pointer to the page structure.
99 * Find the right map and if it's AGP memory find the real physical page to
100 * map, get the page, increment the use count and return it.
102 #if IS_ENABLED(CONFIG_AGP)
103 static vm_fault_t drm_vm_fault(struct vm_fault *vmf)
105 struct vm_area_struct *vma = vmf->vma;
106 struct drm_file *priv = vma->vm_file->private_data;
107 struct drm_device *dev = priv->minor->dev;
108 struct drm_local_map *map = NULL;
109 struct drm_map_list *r_list;
110 struct drm_hash_item *hash;
118 if (!dev->agp || !dev->agp->cant_use_aperture)
121 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
124 r_list = drm_hash_entry(hash, struct drm_map_list, hash);
127 if (map && map->type == _DRM_AGP) {
129 * Using vm_pgoff as a selector forces us to use this unusual
132 resource_size_t offset = vmf->address - vma->vm_start;
133 resource_size_t baddr = map->offset + offset;
134 struct drm_agp_mem *agpmem;
139 * Adjust to a bus-relative address
141 baddr -= dev->hose->mem_space->start;
145 * It's AGP memory - find the real physical page to map
147 list_for_each_entry(agpmem, &dev->agp->memory, head) {
148 if (agpmem->bound <= baddr &&
149 agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
153 if (&agpmem->head == &dev->agp->memory)
157 * Get the page, inc the use count, and return it
159 offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
160 page = agpmem->memory->pages[offset];
165 ("baddr = 0x%llx page = 0x%p, offset = 0x%llx, count=%d\n",
166 (unsigned long long)baddr,
167 agpmem->memory->pages[offset],
168 (unsigned long long)offset,
173 return VM_FAULT_SIGBUS; /* Disallow mremap */
176 static vm_fault_t drm_vm_fault(struct vm_fault *vmf)
178 return VM_FAULT_SIGBUS;
183 * \c nopage method for shared virtual memory.
185 * \param vma virtual memory area.
186 * \param address access address.
187 * \return pointer to the page structure.
189 * Get the mapping, find the real physical page to map, get the page, and
192 static vm_fault_t drm_vm_shm_fault(struct vm_fault *vmf)
194 struct vm_area_struct *vma = vmf->vma;
195 struct drm_local_map *map = vma->vm_private_data;
196 unsigned long offset;
201 return VM_FAULT_SIGBUS; /* Nothing allocated */
203 offset = vmf->address - vma->vm_start;
204 i = (unsigned long)map->handle + offset;
205 page = vmalloc_to_page((void *)i);
207 return VM_FAULT_SIGBUS;
211 DRM_DEBUG("shm_fault 0x%lx\n", offset);
216 * \c close method for shared virtual memory.
218 * \param vma virtual memory area.
220 * Deletes map information if we are the last
221 * person to close a mapping and it's not in the global maplist.
223 static void drm_vm_shm_close(struct vm_area_struct *vma)
225 struct drm_file *priv = vma->vm_file->private_data;
226 struct drm_device *dev = priv->minor->dev;
227 struct drm_vma_entry *pt, *temp;
228 struct drm_local_map *map;
229 struct drm_map_list *r_list;
232 DRM_DEBUG("0x%08lx,0x%08lx\n",
233 vma->vm_start, vma->vm_end - vma->vm_start);
235 map = vma->vm_private_data;
237 mutex_lock(&dev->struct_mutex);
238 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
239 if (pt->vma->vm_private_data == map)
241 if (pt->vma == vma) {
247 /* We were the only map that was found */
248 if (found_maps == 1 && map->flags & _DRM_REMOVABLE) {
249 /* Check to see if we are in the maplist, if we are not, then
250 * we delete this mappings information.
253 list_for_each_entry(r_list, &dev->maplist, head) {
254 if (r_list->map == map)
259 drm_dma_handle_t dmah;
263 case _DRM_FRAME_BUFFER:
264 arch_phys_wc_del(map->mtrr);
265 iounmap(map->handle);
271 case _DRM_SCATTER_GATHER:
273 case _DRM_CONSISTENT:
274 dmah.vaddr = map->handle;
275 dmah.busaddr = map->offset;
276 dmah.size = map->size;
277 __drm_legacy_pci_free(dev, &dmah);
283 mutex_unlock(&dev->struct_mutex);
287 * \c fault method for DMA virtual memory.
289 * \param address access address.
290 * \return pointer to the page structure.
292 * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
294 static vm_fault_t drm_vm_dma_fault(struct vm_fault *vmf)
296 struct vm_area_struct *vma = vmf->vma;
297 struct drm_file *priv = vma->vm_file->private_data;
298 struct drm_device *dev = priv->minor->dev;
299 struct drm_device_dma *dma = dev->dma;
300 unsigned long offset;
301 unsigned long page_nr;
305 return VM_FAULT_SIGBUS; /* Error */
307 return VM_FAULT_SIGBUS; /* Nothing allocated */
309 offset = vmf->address - vma->vm_start;
310 /* vm_[pg]off[set] should be 0 */
311 page_nr = offset >> PAGE_SHIFT; /* page_nr could just be vmf->pgoff */
312 page = virt_to_page((void *)dma->pagelist[page_nr]);
317 DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset, page_nr);
322 * \c fault method for scatter-gather virtual memory.
324 * \param address access address.
325 * \return pointer to the page structure.
327 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
329 static vm_fault_t drm_vm_sg_fault(struct vm_fault *vmf)
331 struct vm_area_struct *vma = vmf->vma;
332 struct drm_local_map *map = vma->vm_private_data;
333 struct drm_file *priv = vma->vm_file->private_data;
334 struct drm_device *dev = priv->minor->dev;
335 struct drm_sg_mem *entry = dev->sg;
336 unsigned long offset;
337 unsigned long map_offset;
338 unsigned long page_offset;
342 return VM_FAULT_SIGBUS; /* Error */
343 if (!entry->pagelist)
344 return VM_FAULT_SIGBUS; /* Nothing allocated */
346 offset = vmf->address - vma->vm_start;
347 map_offset = map->offset - (unsigned long)dev->sg->virtual;
348 page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
349 page = entry->pagelist[page_offset];
356 /** AGP virtual memory operations */
357 static const struct vm_operations_struct drm_vm_ops = {
358 .fault = drm_vm_fault,
360 .close = drm_vm_close,
363 /** Shared virtual memory operations */
364 static const struct vm_operations_struct drm_vm_shm_ops = {
365 .fault = drm_vm_shm_fault,
367 .close = drm_vm_shm_close,
370 /** DMA virtual memory operations */
371 static const struct vm_operations_struct drm_vm_dma_ops = {
372 .fault = drm_vm_dma_fault,
374 .close = drm_vm_close,
377 /** Scatter-gather virtual memory operations */
378 static const struct vm_operations_struct drm_vm_sg_ops = {
379 .fault = drm_vm_sg_fault,
381 .close = drm_vm_close,
384 static void drm_vm_open_locked(struct drm_device *dev,
385 struct vm_area_struct *vma)
387 struct drm_vma_entry *vma_entry;
389 DRM_DEBUG("0x%08lx,0x%08lx\n",
390 vma->vm_start, vma->vm_end - vma->vm_start);
392 vma_entry = kmalloc(sizeof(*vma_entry), GFP_KERNEL);
394 vma_entry->vma = vma;
395 vma_entry->pid = current->pid;
396 list_add(&vma_entry->head, &dev->vmalist);
400 static void drm_vm_open(struct vm_area_struct *vma)
402 struct drm_file *priv = vma->vm_file->private_data;
403 struct drm_device *dev = priv->minor->dev;
405 mutex_lock(&dev->struct_mutex);
406 drm_vm_open_locked(dev, vma);
407 mutex_unlock(&dev->struct_mutex);
410 static void drm_vm_close_locked(struct drm_device *dev,
411 struct vm_area_struct *vma)
413 struct drm_vma_entry *pt, *temp;
415 DRM_DEBUG("0x%08lx,0x%08lx\n",
416 vma->vm_start, vma->vm_end - vma->vm_start);
418 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
419 if (pt->vma == vma) {
428 * \c close method for all virtual memory types.
430 * \param vma virtual memory area.
432 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
435 static void drm_vm_close(struct vm_area_struct *vma)
437 struct drm_file *priv = vma->vm_file->private_data;
438 struct drm_device *dev = priv->minor->dev;
440 mutex_lock(&dev->struct_mutex);
441 drm_vm_close_locked(dev, vma);
442 mutex_unlock(&dev->struct_mutex);
448 * \param file_priv DRM file private.
449 * \param vma virtual memory area.
450 * \return zero on success or a negative number on failure.
452 * Sets the virtual memory area operations structure to vm_dma_ops, the file
453 * pointer, and calls vm_open().
455 static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
457 struct drm_file *priv = filp->private_data;
458 struct drm_device *dev;
459 struct drm_device_dma *dma;
460 unsigned long length = vma->vm_end - vma->vm_start;
462 dev = priv->minor->dev;
464 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
465 vma->vm_start, vma->vm_end, vma->vm_pgoff);
467 /* Length must match exact page count */
468 if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
472 if (!capable(CAP_SYS_ADMIN) &&
473 (dma->flags & _DRM_DMA_USE_PCI_RO)) {
474 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
475 #if defined(__i386__) || defined(__x86_64__)
476 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
478 /* Ye gads this is ugly. With more thought
479 we could move this up higher and use
480 `protection_map' instead. */
484 (__pte(pgprot_val(vma->vm_page_prot)))));
488 vma->vm_ops = &drm_vm_dma_ops;
490 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
492 drm_vm_open_locked(dev, vma);
496 static resource_size_t drm_core_get_reg_ofs(struct drm_device *dev)
499 return dev->hose->dense_mem_base;
508 * \param file_priv DRM file private.
509 * \param vma virtual memory area.
510 * \return zero on success or a negative number on failure.
512 * If the virtual memory area has no offset associated with it then it's a DMA
513 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
514 * checks that the restricted flag is not set, sets the virtual memory operations
515 * according to the mapping type and remaps the pages. Finally sets the file
516 * pointer and calls vm_open().
518 static int drm_mmap_locked(struct file *filp, struct vm_area_struct *vma)
520 struct drm_file *priv = filp->private_data;
521 struct drm_device *dev = priv->minor->dev;
522 struct drm_local_map *map = NULL;
523 resource_size_t offset = 0;
524 struct drm_hash_item *hash;
526 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
527 vma->vm_start, vma->vm_end, vma->vm_pgoff);
529 if (!priv->authenticated)
532 /* We check for "dma". On Apple's UniNorth, it's valid to have
533 * the AGP mapped at physical address 0
537 #if IS_ENABLED(CONFIG_AGP)
539 || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
542 return drm_mmap_dma(filp, vma);
544 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) {
545 DRM_ERROR("Could not find map\n");
549 map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
550 if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
553 /* Check for valid size. */
554 if (map->size < vma->vm_end - vma->vm_start)
557 if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
558 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
559 #if defined(__i386__) || defined(__x86_64__)
560 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
562 /* Ye gads this is ugly. With more thought
563 we could move this up higher and use
564 `protection_map' instead. */
568 (__pte(pgprot_val(vma->vm_page_prot)))));
573 #if !defined(__arm__)
575 if (dev->agp && dev->agp->cant_use_aperture) {
577 * On some platforms we can't talk to bus dma address from the CPU, so for
578 * memory of type DRM_AGP, we'll deal with sorting out the real physical
579 * pages and mappings in fault()
581 #if defined(__powerpc__)
582 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
584 vma->vm_ops = &drm_vm_ops;
588 /* fall through - to _DRM_FRAME_BUFFER... */
589 case _DRM_FRAME_BUFFER:
591 offset = drm_core_get_reg_ofs(dev);
592 vma->vm_page_prot = drm_io_prot(map, vma);
593 if (io_remap_pfn_range(vma, vma->vm_start,
594 (map->offset + offset) >> PAGE_SHIFT,
595 vma->vm_end - vma->vm_start,
598 DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx,"
599 " offset = 0x%llx\n",
601 vma->vm_start, vma->vm_end, (unsigned long long)(map->offset + offset));
603 vma->vm_ops = &drm_vm_ops;
605 case _DRM_CONSISTENT:
606 /* Consistent memory is really like shared memory. But
607 * it's allocated in a different way, so avoid fault */
608 if (remap_pfn_range(vma, vma->vm_start,
609 page_to_pfn(virt_to_page(map->handle)),
610 vma->vm_end - vma->vm_start, vma->vm_page_prot))
612 vma->vm_page_prot = drm_dma_prot(map->type, vma);
613 /* fall through - to _DRM_SHM */
615 vma->vm_ops = &drm_vm_shm_ops;
616 vma->vm_private_data = (void *)map;
618 case _DRM_SCATTER_GATHER:
619 vma->vm_ops = &drm_vm_sg_ops;
620 vma->vm_private_data = (void *)map;
621 vma->vm_page_prot = drm_dma_prot(map->type, vma);
624 return -EINVAL; /* This should never happen. */
626 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
628 drm_vm_open_locked(dev, vma);
632 int drm_legacy_mmap(struct file *filp, struct vm_area_struct *vma)
634 struct drm_file *priv = filp->private_data;
635 struct drm_device *dev = priv->minor->dev;
638 if (drm_dev_is_unplugged(dev))
641 mutex_lock(&dev->struct_mutex);
642 ret = drm_mmap_locked(filp, vma);
643 mutex_unlock(&dev->struct_mutex);
647 EXPORT_SYMBOL(drm_legacy_mmap);
649 #if IS_ENABLED(CONFIG_DRM_LEGACY)
650 void drm_legacy_vma_flush(struct drm_device *dev)
652 struct drm_vma_entry *vma, *vma_temp;
654 /* Clear vma list (only needed for legacy drivers) */
655 list_for_each_entry_safe(vma, vma_temp, &dev->vmalist, head) {
656 list_del(&vma->head);