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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 "drmP.h"
37#if defined(__ia64__)
38#include <linux/efi.h>
39#include <linux/slab.h>
40#endif
41
42static void drm_vm_open(struct vm_area_struct *vma);
43static void drm_vm_close(struct vm_area_struct *vma);
44
45static pgprot_t drm_io_prot(uint32_t map_type, struct vm_area_struct *vma)
46{
47 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
48
49#if defined(__i386__) || defined(__x86_64__)
50 if (boot_cpu_data.x86 > 3 && map_type != _DRM_AGP) {
51 pgprot_val(tmp) |= _PAGE_PCD;
52 pgprot_val(tmp) &= ~_PAGE_PWT;
53 }
54#elif defined(__powerpc__)
55 pgprot_val(tmp) |= _PAGE_NO_CACHE;
56 if (map_type == _DRM_REGISTERS)
57 pgprot_val(tmp) |= _PAGE_GUARDED;
58#elif defined(__ia64__)
59 if (efi_range_is_wc(vma->vm_start, vma->vm_end -
60 vma->vm_start))
61 tmp = pgprot_writecombine(tmp);
62 else
63 tmp = pgprot_noncached(tmp);
64#elif defined(__sparc__) || defined(__arm__)
65 tmp = pgprot_noncached(tmp);
66#endif
67 return tmp;
68}
69
70static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma)
71{
72 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
73
74#if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
75 tmp |= _PAGE_NO_CACHE;
76#endif
77 return tmp;
78}
79
80/**
81 * \c fault method for AGP virtual memory.
82 *
83 * \param vma virtual memory area.
84 * \param address access address.
85 * \return pointer to the page structure.
86 *
87 * Find the right map and if it's AGP memory find the real physical page to
88 * map, get the page, increment the use count and return it.
89 */
90#if __OS_HAS_AGP
91static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
92{
93 struct drm_file *priv = vma->vm_file->private_data;
94 struct drm_device *dev = priv->minor->dev;
95 struct drm_local_map *map = NULL;
96 struct drm_map_list *r_list;
97 struct drm_hash_item *hash;
98
99 /*
100 * Find the right map
101 */
102 if (!drm_core_has_AGP(dev))
103 goto vm_fault_error;
104
105 if (!dev->agp || !dev->agp->cant_use_aperture)
106 goto vm_fault_error;
107
108 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
109 goto vm_fault_error;
110
111 r_list = drm_hash_entry(hash, struct drm_map_list, hash);
112 map = r_list->map;
113
114 if (map && map->type == _DRM_AGP) {
115 /*
116 * Using vm_pgoff as a selector forces us to use this unusual
117 * addressing scheme.
118 */
119 resource_size_t offset = (unsigned long)vmf->virtual_address -
120 vma->vm_start;
121 resource_size_t baddr = map->offset + offset;
122 struct drm_agp_mem *agpmem;
123 struct page *page;
124
125#ifdef __alpha__
126 /*
127 * Adjust to a bus-relative address
128 */
129 baddr -= dev->hose->mem_space->start;
130#endif
131
132 /*
133 * It's AGP memory - find the real physical page to map
134 */
135 list_for_each_entry(agpmem, &dev->agp->memory, head) {
136 if (agpmem->bound <= baddr &&
137 agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
138 break;
139 }
140
141 if (&agpmem->head == &dev->agp->memory)
142 goto vm_fault_error;
143
144 /*
145 * Get the page, inc the use count, and return it
146 */
147 offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
148 page = agpmem->memory->pages[offset];
149 get_page(page);
150 vmf->page = page;
151
152 DRM_DEBUG
153 ("baddr = 0x%llx page = 0x%p, offset = 0x%llx, count=%d\n",
154 (unsigned long long)baddr,
155 agpmem->memory->pages[offset],
156 (unsigned long long)offset,
157 page_count(page));
158 return 0;
159 }
160vm_fault_error:
161 return VM_FAULT_SIGBUS; /* Disallow mremap */
162}
163#else /* __OS_HAS_AGP */
164static int drm_do_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
165{
166 return VM_FAULT_SIGBUS;
167}
168#endif /* __OS_HAS_AGP */
169
170/**
171 * \c nopage method for shared virtual memory.
172 *
173 * \param vma virtual memory area.
174 * \param address access address.
175 * \return pointer to the page structure.
176 *
177 * Get the mapping, find the real physical page to map, get the page, and
178 * return it.
179 */
180static int drm_do_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
181{
182 struct drm_local_map *map = vma->vm_private_data;
183 unsigned long offset;
184 unsigned long i;
185 struct page *page;
186
187 if (!map)
188 return VM_FAULT_SIGBUS; /* Nothing allocated */
189
190 offset = (unsigned long)vmf->virtual_address - vma->vm_start;
191 i = (unsigned long)map->handle + offset;
192 page = vmalloc_to_page((void *)i);
193 if (!page)
194 return VM_FAULT_SIGBUS;
195 get_page(page);
196 vmf->page = page;
197
198 DRM_DEBUG("shm_fault 0x%lx\n", offset);
199 return 0;
200}
201
202/**
203 * \c close method for shared virtual memory.
204 *
205 * \param vma virtual memory area.
206 *
207 * Deletes map information if we are the last
208 * person to close a mapping and it's not in the global maplist.
209 */
210static void drm_vm_shm_close(struct vm_area_struct *vma)
211{
212 struct drm_file *priv = vma->vm_file->private_data;
213 struct drm_device *dev = priv->minor->dev;
214 struct drm_vma_entry *pt, *temp;
215 struct drm_local_map *map;
216 struct drm_map_list *r_list;
217 int found_maps = 0;
218
219 DRM_DEBUG("0x%08lx,0x%08lx\n",
220 vma->vm_start, vma->vm_end - vma->vm_start);
221 atomic_dec(&dev->vma_count);
222
223 map = vma->vm_private_data;
224
225 mutex_lock(&dev->struct_mutex);
226 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
227 if (pt->vma->vm_private_data == map)
228 found_maps++;
229 if (pt->vma == vma) {
230 list_del(&pt->head);
231 kfree(pt);
232 }
233 }
234
235 /* We were the only map that was found */
236 if (found_maps == 1 && map->flags & _DRM_REMOVABLE) {
237 /* Check to see if we are in the maplist, if we are not, then
238 * we delete this mappings information.
239 */
240 found_maps = 0;
241 list_for_each_entry(r_list, &dev->maplist, head) {
242 if (r_list->map == map)
243 found_maps++;
244 }
245
246 if (!found_maps) {
247 drm_dma_handle_t dmah;
248
249 switch (map->type) {
250 case _DRM_REGISTERS:
251 case _DRM_FRAME_BUFFER:
252 if (drm_core_has_MTRR(dev) && map->mtrr >= 0) {
253 int retcode;
254 retcode = mtrr_del(map->mtrr,
255 map->offset,
256 map->size);
257 DRM_DEBUG("mtrr_del = %d\n", retcode);
258 }
259 iounmap(map->handle);
260 break;
261 case _DRM_SHM:
262 vfree(map->handle);
263 break;
264 case _DRM_AGP:
265 case _DRM_SCATTER_GATHER:
266 break;
267 case _DRM_CONSISTENT:
268 dmah.vaddr = map->handle;
269 dmah.busaddr = map->offset;
270 dmah.size = map->size;
271 __drm_pci_free(dev, &dmah);
272 break;
273 case _DRM_GEM:
274 DRM_ERROR("tried to rmmap GEM object\n");
275 break;
276 }
277 kfree(map);
278 }
279 }
280 mutex_unlock(&dev->struct_mutex);
281}
282
283/**
284 * \c fault method for DMA virtual memory.
285 *
286 * \param vma virtual memory area.
287 * \param address access address.
288 * \return pointer to the page structure.
289 *
290 * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
291 */
292static int drm_do_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
293{
294 struct drm_file *priv = vma->vm_file->private_data;
295 struct drm_device *dev = priv->minor->dev;
296 struct drm_device_dma *dma = dev->dma;
297 unsigned long offset;
298 unsigned long page_nr;
299 struct page *page;
300
301 if (!dma)
302 return VM_FAULT_SIGBUS; /* Error */
303 if (!dma->pagelist)
304 return VM_FAULT_SIGBUS; /* Nothing allocated */
305
306 offset = (unsigned long)vmf->virtual_address - vma->vm_start; /* vm_[pg]off[set] should be 0 */
307 page_nr = offset >> PAGE_SHIFT; /* page_nr could just be vmf->pgoff */
308 page = virt_to_page((dma->pagelist[page_nr] + (offset & (~PAGE_MASK))));
309
310 get_page(page);
311 vmf->page = page;
312
313 DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset, page_nr);
314 return 0;
315}
316
317/**
318 * \c fault method for scatter-gather virtual memory.
319 *
320 * \param vma virtual memory area.
321 * \param address access address.
322 * \return pointer to the page structure.
323 *
324 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
325 */
326static int drm_do_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
327{
328 struct drm_local_map *map = vma->vm_private_data;
329 struct drm_file *priv = vma->vm_file->private_data;
330 struct drm_device *dev = priv->minor->dev;
331 struct drm_sg_mem *entry = dev->sg;
332 unsigned long offset;
333 unsigned long map_offset;
334 unsigned long page_offset;
335 struct page *page;
336
337 if (!entry)
338 return VM_FAULT_SIGBUS; /* Error */
339 if (!entry->pagelist)
340 return VM_FAULT_SIGBUS; /* Nothing allocated */
341
342 offset = (unsigned long)vmf->virtual_address - vma->vm_start;
343 map_offset = map->offset - (unsigned long)dev->sg->virtual;
344 page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
345 page = entry->pagelist[page_offset];
346 get_page(page);
347 vmf->page = page;
348
349 return 0;
350}
351
352static int drm_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
353{
354 return drm_do_vm_fault(vma, vmf);
355}
356
357static int drm_vm_shm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
358{
359 return drm_do_vm_shm_fault(vma, vmf);
360}
361
362static int drm_vm_dma_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
363{
364 return drm_do_vm_dma_fault(vma, vmf);
365}
366
367static int drm_vm_sg_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
368{
369 return drm_do_vm_sg_fault(vma, vmf);
370}
371
372/** AGP virtual memory operations */
373static const struct vm_operations_struct drm_vm_ops = {
374 .fault = drm_vm_fault,
375 .open = drm_vm_open,
376 .close = drm_vm_close,
377};
378
379/** Shared virtual memory operations */
380static const struct vm_operations_struct drm_vm_shm_ops = {
381 .fault = drm_vm_shm_fault,
382 .open = drm_vm_open,
383 .close = drm_vm_shm_close,
384};
385
386/** DMA virtual memory operations */
387static const struct vm_operations_struct drm_vm_dma_ops = {
388 .fault = drm_vm_dma_fault,
389 .open = drm_vm_open,
390 .close = drm_vm_close,
391};
392
393/** Scatter-gather virtual memory operations */
394static const struct vm_operations_struct drm_vm_sg_ops = {
395 .fault = drm_vm_sg_fault,
396 .open = drm_vm_open,
397 .close = drm_vm_close,
398};
399
400/**
401 * \c open method for shared virtual memory.
402 *
403 * \param vma virtual memory area.
404 *
405 * Create a new drm_vma_entry structure as the \p vma private data entry and
406 * add it to drm_device::vmalist.
407 */
408void drm_vm_open_locked(struct vm_area_struct *vma)
409{
410 struct drm_file *priv = vma->vm_file->private_data;
411 struct drm_device *dev = priv->minor->dev;
412 struct drm_vma_entry *vma_entry;
413
414 DRM_DEBUG("0x%08lx,0x%08lx\n",
415 vma->vm_start, vma->vm_end - vma->vm_start);
416 atomic_inc(&dev->vma_count);
417
418 vma_entry = kmalloc(sizeof(*vma_entry), GFP_KERNEL);
419 if (vma_entry) {
420 vma_entry->vma = vma;
421 vma_entry->pid = current->pid;
422 list_add(&vma_entry->head, &dev->vmalist);
423 }
424}
425
426static void drm_vm_open(struct vm_area_struct *vma)
427{
428 struct drm_file *priv = vma->vm_file->private_data;
429 struct drm_device *dev = priv->minor->dev;
430
431 mutex_lock(&dev->struct_mutex);
432 drm_vm_open_locked(vma);
433 mutex_unlock(&dev->struct_mutex);
434}
435
436void drm_vm_close_locked(struct vm_area_struct *vma)
437{
438 struct drm_file *priv = vma->vm_file->private_data;
439 struct drm_device *dev = priv->minor->dev;
440 struct drm_vma_entry *pt, *temp;
441
442 DRM_DEBUG("0x%08lx,0x%08lx\n",
443 vma->vm_start, vma->vm_end - vma->vm_start);
444 atomic_dec(&dev->vma_count);
445
446 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
447 if (pt->vma == vma) {
448 list_del(&pt->head);
449 kfree(pt);
450 break;
451 }
452 }
453}
454
455/**
456 * \c close method for all virtual memory types.
457 *
458 * \param vma virtual memory area.
459 *
460 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
461 * free it.
462 */
463static void drm_vm_close(struct vm_area_struct *vma)
464{
465 struct drm_file *priv = vma->vm_file->private_data;
466 struct drm_device *dev = priv->minor->dev;
467
468 mutex_lock(&dev->struct_mutex);
469 drm_vm_close_locked(vma);
470 mutex_unlock(&dev->struct_mutex);
471}
472
473/**
474 * mmap DMA memory.
475 *
476 * \param file_priv DRM file private.
477 * \param vma virtual memory area.
478 * \return zero on success or a negative number on failure.
479 *
480 * Sets the virtual memory area operations structure to vm_dma_ops, the file
481 * pointer, and calls vm_open().
482 */
483static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
484{
485 struct drm_file *priv = filp->private_data;
486 struct drm_device *dev;
487 struct drm_device_dma *dma;
488 unsigned long length = vma->vm_end - vma->vm_start;
489
490 dev = priv->minor->dev;
491 dma = dev->dma;
492 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
493 vma->vm_start, vma->vm_end, vma->vm_pgoff);
494
495 /* Length must match exact page count */
496 if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
497 return -EINVAL;
498 }
499
500 if (!capable(CAP_SYS_ADMIN) &&
501 (dma->flags & _DRM_DMA_USE_PCI_RO)) {
502 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
503#if defined(__i386__) || defined(__x86_64__)
504 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
505#else
506 /* Ye gads this is ugly. With more thought
507 we could move this up higher and use
508 `protection_map' instead. */
509 vma->vm_page_prot =
510 __pgprot(pte_val
511 (pte_wrprotect
512 (__pte(pgprot_val(vma->vm_page_prot)))));
513#endif
514 }
515
516 vma->vm_ops = &drm_vm_dma_ops;
517
518 vma->vm_flags |= VM_RESERVED; /* Don't swap */
519 vma->vm_flags |= VM_DONTEXPAND;
520
521 vma->vm_file = filp; /* Needed for drm_vm_open() */
522 drm_vm_open_locked(vma);
523 return 0;
524}
525
526static resource_size_t drm_core_get_reg_ofs(struct drm_device *dev)
527{
528#ifdef __alpha__
529 return dev->hose->dense_mem_base;
530#else
531 return 0;
532#endif
533}
534
535/**
536 * mmap DMA memory.
537 *
538 * \param file_priv DRM file private.
539 * \param vma virtual memory area.
540 * \return zero on success or a negative number on failure.
541 *
542 * If the virtual memory area has no offset associated with it then it's a DMA
543 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
544 * checks that the restricted flag is not set, sets the virtual memory operations
545 * according to the mapping type and remaps the pages. Finally sets the file
546 * pointer and calls vm_open().
547 */
548int drm_mmap_locked(struct file *filp, struct vm_area_struct *vma)
549{
550 struct drm_file *priv = filp->private_data;
551 struct drm_device *dev = priv->minor->dev;
552 struct drm_local_map *map = NULL;
553 resource_size_t offset = 0;
554 struct drm_hash_item *hash;
555
556 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
557 vma->vm_start, vma->vm_end, vma->vm_pgoff);
558
559 if (!priv->authenticated)
560 return -EACCES;
561
562 /* We check for "dma". On Apple's UniNorth, it's valid to have
563 * the AGP mapped at physical address 0
564 * --BenH.
565 */
566 if (!vma->vm_pgoff
567#if __OS_HAS_AGP
568 && (!dev->agp
569 || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
570#endif
571 )
572 return drm_mmap_dma(filp, vma);
573
574 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) {
575 DRM_ERROR("Could not find map\n");
576 return -EINVAL;
577 }
578
579 map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
580 if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
581 return -EPERM;
582
583 /* Check for valid size. */
584 if (map->size < vma->vm_end - vma->vm_start)
585 return -EINVAL;
586
587 if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
588 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
589#if defined(__i386__) || defined(__x86_64__)
590 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
591#else
592 /* Ye gads this is ugly. With more thought
593 we could move this up higher and use
594 `protection_map' instead. */
595 vma->vm_page_prot =
596 __pgprot(pte_val
597 (pte_wrprotect
598 (__pte(pgprot_val(vma->vm_page_prot)))));
599#endif
600 }
601
602 switch (map->type) {
603#if !defined(__arm__)
604 case _DRM_AGP:
605 if (drm_core_has_AGP(dev) && dev->agp->cant_use_aperture) {
606 /*
607 * On some platforms we can't talk to bus dma address from the CPU, so for
608 * memory of type DRM_AGP, we'll deal with sorting out the real physical
609 * pages and mappings in fault()
610 */
611#if defined(__powerpc__)
612 pgprot_val(vma->vm_page_prot) |= _PAGE_NO_CACHE;
613#endif
614 vma->vm_ops = &drm_vm_ops;
615 break;
616 }
617 /* fall through to _DRM_FRAME_BUFFER... */
618#endif
619 case _DRM_FRAME_BUFFER:
620 case _DRM_REGISTERS:
621 offset = drm_core_get_reg_ofs(dev);
622 vma->vm_flags |= VM_IO; /* not in core dump */
623 vma->vm_page_prot = drm_io_prot(map->type, vma);
624#if !defined(__arm__)
625 if (io_remap_pfn_range(vma, vma->vm_start,
626 (map->offset + offset) >> PAGE_SHIFT,
627 vma->vm_end - vma->vm_start,
628 vma->vm_page_prot))
629 return -EAGAIN;
630#else
631 if (remap_pfn_range(vma, vma->vm_start,
632 (map->offset + offset) >> PAGE_SHIFT,
633 vma->vm_end - vma->vm_start,
634 vma->vm_page_prot))
635 return -EAGAIN;
636#endif
637
638 DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx,"
639 " offset = 0x%llx\n",
640 map->type,
641 vma->vm_start, vma->vm_end, (unsigned long long)(map->offset + offset));
642
643 vma->vm_ops = &drm_vm_ops;
644 break;
645 case _DRM_CONSISTENT:
646 /* Consistent memory is really like shared memory. But
647 * it's allocated in a different way, so avoid fault */
648 if (remap_pfn_range(vma, vma->vm_start,
649 page_to_pfn(virt_to_page(map->handle)),
650 vma->vm_end - vma->vm_start, vma->vm_page_prot))
651 return -EAGAIN;
652 vma->vm_page_prot = drm_dma_prot(map->type, vma);
653 /* fall through to _DRM_SHM */
654 case _DRM_SHM:
655 vma->vm_ops = &drm_vm_shm_ops;
656 vma->vm_private_data = (void *)map;
657 /* Don't let this area swap. Change when
658 DRM_KERNEL advisory is supported. */
659 vma->vm_flags |= VM_RESERVED;
660 break;
661 case _DRM_SCATTER_GATHER:
662 vma->vm_ops = &drm_vm_sg_ops;
663 vma->vm_private_data = (void *)map;
664 vma->vm_flags |= VM_RESERVED;
665 vma->vm_page_prot = drm_dma_prot(map->type, vma);
666 break;
667 default:
668 return -EINVAL; /* This should never happen. */
669 }
670 vma->vm_flags |= VM_RESERVED; /* Don't swap */
671 vma->vm_flags |= VM_DONTEXPAND;
672
673 vma->vm_file = filp; /* Needed for drm_vm_open() */
674 drm_vm_open_locked(vma);
675 return 0;
676}
677
678int drm_mmap(struct file *filp, struct vm_area_struct *vma)
679{
680 struct drm_file *priv = filp->private_data;
681 struct drm_device *dev = priv->minor->dev;
682 int ret;
683
684 mutex_lock(&dev->struct_mutex);
685 ret = drm_mmap_locked(filp, vma);
686 mutex_unlock(&dev->struct_mutex);
687
688 return ret;
689}
690EXPORT_SYMBOL(drm_mmap);
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#include <drm/drm_device.h>
49#include <drm/drm_drv.h>
50#include <drm/drm_file.h>
51#include <drm/drm_framebuffer.h>
52#include <drm/drm_print.h>
53
54#include "drm_internal.h"
55#include "drm_legacy.h"
56
57struct drm_vma_entry {
58 struct list_head head;
59 struct vm_area_struct *vma;
60 pid_t pid;
61};
62
63static void drm_vm_open(struct vm_area_struct *vma);
64static void drm_vm_close(struct vm_area_struct *vma);
65
66static pgprot_t drm_io_prot(struct drm_local_map *map,
67 struct vm_area_struct *vma)
68{
69 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
70
71#if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__) || \
72 defined(__mips__) || defined(__loongarch__)
73 if (map->type == _DRM_REGISTERS && !(map->flags & _DRM_WRITE_COMBINING))
74 tmp = pgprot_noncached(tmp);
75 else
76 tmp = pgprot_writecombine(tmp);
77#elif defined(__ia64__)
78 if (efi_range_is_wc(vma->vm_start, vma->vm_end -
79 vma->vm_start))
80 tmp = pgprot_writecombine(tmp);
81 else
82 tmp = pgprot_noncached(tmp);
83#elif defined(__sparc__) || defined(__arm__)
84 tmp = pgprot_noncached(tmp);
85#endif
86 return tmp;
87}
88
89static pgprot_t drm_dma_prot(uint32_t map_type, struct vm_area_struct *vma)
90{
91 pgprot_t tmp = vm_get_page_prot(vma->vm_flags);
92
93#if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
94 tmp = pgprot_noncached_wc(tmp);
95#endif
96 return tmp;
97}
98
99/*
100 * \c fault method for AGP virtual memory.
101 *
102 * \param vma virtual memory area.
103 * \param address access address.
104 * \return pointer to the page structure.
105 *
106 * Find the right map and if it's AGP memory find the real physical page to
107 * map, get the page, increment the use count and return it.
108 */
109#if IS_ENABLED(CONFIG_AGP)
110static vm_fault_t drm_vm_fault(struct vm_fault *vmf)
111{
112 struct vm_area_struct *vma = vmf->vma;
113 struct drm_file *priv = vma->vm_file->private_data;
114 struct drm_device *dev = priv->minor->dev;
115 struct drm_local_map *map = NULL;
116 struct drm_map_list *r_list;
117 struct drm_hash_item *hash;
118
119 /*
120 * Find the right map
121 */
122 if (!dev->agp)
123 goto vm_fault_error;
124
125 if (!dev->agp || !dev->agp->cant_use_aperture)
126 goto vm_fault_error;
127
128 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash))
129 goto vm_fault_error;
130
131 r_list = drm_hash_entry(hash, struct drm_map_list, hash);
132 map = r_list->map;
133
134 if (map && map->type == _DRM_AGP) {
135 /*
136 * Using vm_pgoff as a selector forces us to use this unusual
137 * addressing scheme.
138 */
139 resource_size_t offset = vmf->address - vma->vm_start;
140 resource_size_t baddr = map->offset + offset;
141 struct drm_agp_mem *agpmem;
142 struct page *page;
143
144#ifdef __alpha__
145 /*
146 * Adjust to a bus-relative address
147 */
148 baddr -= dev->hose->mem_space->start;
149#endif
150
151 /*
152 * It's AGP memory - find the real physical page to map
153 */
154 list_for_each_entry(agpmem, &dev->agp->memory, head) {
155 if (agpmem->bound <= baddr &&
156 agpmem->bound + agpmem->pages * PAGE_SIZE > baddr)
157 break;
158 }
159
160 if (&agpmem->head == &dev->agp->memory)
161 goto vm_fault_error;
162
163 /*
164 * Get the page, inc the use count, and return it
165 */
166 offset = (baddr - agpmem->bound) >> PAGE_SHIFT;
167 page = agpmem->memory->pages[offset];
168 get_page(page);
169 vmf->page = page;
170
171 DRM_DEBUG
172 ("baddr = 0x%llx page = 0x%p, offset = 0x%llx, count=%d\n",
173 (unsigned long long)baddr,
174 agpmem->memory->pages[offset],
175 (unsigned long long)offset,
176 page_count(page));
177 return 0;
178 }
179vm_fault_error:
180 return VM_FAULT_SIGBUS; /* Disallow mremap */
181}
182#else
183static vm_fault_t drm_vm_fault(struct vm_fault *vmf)
184{
185 return VM_FAULT_SIGBUS;
186}
187#endif
188
189/*
190 * \c nopage method for shared virtual memory.
191 *
192 * \param vma virtual memory area.
193 * \param address access address.
194 * \return pointer to the page structure.
195 *
196 * Get the mapping, find the real physical page to map, get the page, and
197 * return it.
198 */
199static vm_fault_t drm_vm_shm_fault(struct vm_fault *vmf)
200{
201 struct vm_area_struct *vma = vmf->vma;
202 struct drm_local_map *map = vma->vm_private_data;
203 unsigned long offset;
204 unsigned long i;
205 struct page *page;
206
207 if (!map)
208 return VM_FAULT_SIGBUS; /* Nothing allocated */
209
210 offset = vmf->address - vma->vm_start;
211 i = (unsigned long)map->handle + offset;
212 page = vmalloc_to_page((void *)i);
213 if (!page)
214 return VM_FAULT_SIGBUS;
215 get_page(page);
216 vmf->page = page;
217
218 DRM_DEBUG("shm_fault 0x%lx\n", offset);
219 return 0;
220}
221
222/*
223 * \c close method for shared virtual memory.
224 *
225 * \param vma virtual memory area.
226 *
227 * Deletes map information if we are the last
228 * person to close a mapping and it's not in the global maplist.
229 */
230static void drm_vm_shm_close(struct vm_area_struct *vma)
231{
232 struct drm_file *priv = vma->vm_file->private_data;
233 struct drm_device *dev = priv->minor->dev;
234 struct drm_vma_entry *pt, *temp;
235 struct drm_local_map *map;
236 struct drm_map_list *r_list;
237 int found_maps = 0;
238
239 DRM_DEBUG("0x%08lx,0x%08lx\n",
240 vma->vm_start, vma->vm_end - vma->vm_start);
241
242 map = vma->vm_private_data;
243
244 mutex_lock(&dev->struct_mutex);
245 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
246 if (pt->vma->vm_private_data == map)
247 found_maps++;
248 if (pt->vma == vma) {
249 list_del(&pt->head);
250 kfree(pt);
251 }
252 }
253
254 /* We were the only map that was found */
255 if (found_maps == 1 && map->flags & _DRM_REMOVABLE) {
256 /* Check to see if we are in the maplist, if we are not, then
257 * we delete this mappings information.
258 */
259 found_maps = 0;
260 list_for_each_entry(r_list, &dev->maplist, head) {
261 if (r_list->map == map)
262 found_maps++;
263 }
264
265 if (!found_maps) {
266 switch (map->type) {
267 case _DRM_REGISTERS:
268 case _DRM_FRAME_BUFFER:
269 arch_phys_wc_del(map->mtrr);
270 iounmap(map->handle);
271 break;
272 case _DRM_SHM:
273 vfree(map->handle);
274 break;
275 case _DRM_AGP:
276 case _DRM_SCATTER_GATHER:
277 break;
278 case _DRM_CONSISTENT:
279 dma_free_coherent(dev->dev,
280 map->size,
281 map->handle,
282 map->offset);
283 break;
284 }
285 kfree(map);
286 }
287 }
288 mutex_unlock(&dev->struct_mutex);
289}
290
291/*
292 * \c fault method for DMA virtual memory.
293 *
294 * \param address access address.
295 * \return pointer to the page structure.
296 *
297 * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
298 */
299static vm_fault_t drm_vm_dma_fault(struct vm_fault *vmf)
300{
301 struct vm_area_struct *vma = vmf->vma;
302 struct drm_file *priv = vma->vm_file->private_data;
303 struct drm_device *dev = priv->minor->dev;
304 struct drm_device_dma *dma = dev->dma;
305 unsigned long offset;
306 unsigned long page_nr;
307 struct page *page;
308
309 if (!dma)
310 return VM_FAULT_SIGBUS; /* Error */
311 if (!dma->pagelist)
312 return VM_FAULT_SIGBUS; /* Nothing allocated */
313
314 offset = vmf->address - vma->vm_start;
315 /* vm_[pg]off[set] should be 0 */
316 page_nr = offset >> PAGE_SHIFT; /* page_nr could just be vmf->pgoff */
317 page = virt_to_page((void *)dma->pagelist[page_nr]);
318
319 get_page(page);
320 vmf->page = page;
321
322 DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset, page_nr);
323 return 0;
324}
325
326/*
327 * \c fault method for scatter-gather virtual memory.
328 *
329 * \param address access address.
330 * \return pointer to the page structure.
331 *
332 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
333 */
334static vm_fault_t drm_vm_sg_fault(struct vm_fault *vmf)
335{
336 struct vm_area_struct *vma = vmf->vma;
337 struct drm_local_map *map = vma->vm_private_data;
338 struct drm_file *priv = vma->vm_file->private_data;
339 struct drm_device *dev = priv->minor->dev;
340 struct drm_sg_mem *entry = dev->sg;
341 unsigned long offset;
342 unsigned long map_offset;
343 unsigned long page_offset;
344 struct page *page;
345
346 if (!entry)
347 return VM_FAULT_SIGBUS; /* Error */
348 if (!entry->pagelist)
349 return VM_FAULT_SIGBUS; /* Nothing allocated */
350
351 offset = vmf->address - vma->vm_start;
352 map_offset = map->offset - (unsigned long)dev->sg->virtual;
353 page_offset = (offset >> PAGE_SHIFT) + (map_offset >> PAGE_SHIFT);
354 page = entry->pagelist[page_offset];
355 get_page(page);
356 vmf->page = page;
357
358 return 0;
359}
360
361/** AGP virtual memory operations */
362static const struct vm_operations_struct drm_vm_ops = {
363 .fault = drm_vm_fault,
364 .open = drm_vm_open,
365 .close = drm_vm_close,
366};
367
368/** Shared virtual memory operations */
369static const struct vm_operations_struct drm_vm_shm_ops = {
370 .fault = drm_vm_shm_fault,
371 .open = drm_vm_open,
372 .close = drm_vm_shm_close,
373};
374
375/** DMA virtual memory operations */
376static const struct vm_operations_struct drm_vm_dma_ops = {
377 .fault = drm_vm_dma_fault,
378 .open = drm_vm_open,
379 .close = drm_vm_close,
380};
381
382/** Scatter-gather virtual memory operations */
383static const struct vm_operations_struct drm_vm_sg_ops = {
384 .fault = drm_vm_sg_fault,
385 .open = drm_vm_open,
386 .close = drm_vm_close,
387};
388
389static void drm_vm_open_locked(struct drm_device *dev,
390 struct vm_area_struct *vma)
391{
392 struct drm_vma_entry *vma_entry;
393
394 DRM_DEBUG("0x%08lx,0x%08lx\n",
395 vma->vm_start, vma->vm_end - vma->vm_start);
396
397 vma_entry = kmalloc(sizeof(*vma_entry), GFP_KERNEL);
398 if (vma_entry) {
399 vma_entry->vma = vma;
400 vma_entry->pid = current->pid;
401 list_add(&vma_entry->head, &dev->vmalist);
402 }
403}
404
405static void drm_vm_open(struct vm_area_struct *vma)
406{
407 struct drm_file *priv = vma->vm_file->private_data;
408 struct drm_device *dev = priv->minor->dev;
409
410 mutex_lock(&dev->struct_mutex);
411 drm_vm_open_locked(dev, vma);
412 mutex_unlock(&dev->struct_mutex);
413}
414
415static void drm_vm_close_locked(struct drm_device *dev,
416 struct vm_area_struct *vma)
417{
418 struct drm_vma_entry *pt, *temp;
419
420 DRM_DEBUG("0x%08lx,0x%08lx\n",
421 vma->vm_start, vma->vm_end - vma->vm_start);
422
423 list_for_each_entry_safe(pt, temp, &dev->vmalist, head) {
424 if (pt->vma == vma) {
425 list_del(&pt->head);
426 kfree(pt);
427 break;
428 }
429 }
430}
431
432/*
433 * \c close method for all virtual memory types.
434 *
435 * \param vma virtual memory area.
436 *
437 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
438 * free it.
439 */
440static void drm_vm_close(struct vm_area_struct *vma)
441{
442 struct drm_file *priv = vma->vm_file->private_data;
443 struct drm_device *dev = priv->minor->dev;
444
445 mutex_lock(&dev->struct_mutex);
446 drm_vm_close_locked(dev, vma);
447 mutex_unlock(&dev->struct_mutex);
448}
449
450/*
451 * mmap DMA memory.
452 *
453 * \param file_priv DRM file private.
454 * \param vma virtual memory area.
455 * \return zero on success or a negative number on failure.
456 *
457 * Sets the virtual memory area operations structure to vm_dma_ops, the file
458 * pointer, and calls vm_open().
459 */
460static int drm_mmap_dma(struct file *filp, struct vm_area_struct *vma)
461{
462 struct drm_file *priv = filp->private_data;
463 struct drm_device *dev;
464 struct drm_device_dma *dma;
465 unsigned long length = vma->vm_end - vma->vm_start;
466
467 dev = priv->minor->dev;
468 dma = dev->dma;
469 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
470 vma->vm_start, vma->vm_end, vma->vm_pgoff);
471
472 /* Length must match exact page count */
473 if (!dma || (length >> PAGE_SHIFT) != dma->page_count) {
474 return -EINVAL;
475 }
476
477 if (!capable(CAP_SYS_ADMIN) &&
478 (dma->flags & _DRM_DMA_USE_PCI_RO)) {
479 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
480#if defined(__i386__) || defined(__x86_64__)
481 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
482#else
483 /* Ye gads this is ugly. With more thought
484 we could move this up higher and use
485 `protection_map' instead. */
486 vma->vm_page_prot =
487 __pgprot(pte_val
488 (pte_wrprotect
489 (__pte(pgprot_val(vma->vm_page_prot)))));
490#endif
491 }
492
493 vma->vm_ops = &drm_vm_dma_ops;
494
495 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
496
497 drm_vm_open_locked(dev, vma);
498 return 0;
499}
500
501static resource_size_t drm_core_get_reg_ofs(struct drm_device *dev)
502{
503#ifdef __alpha__
504 return dev->hose->dense_mem_base;
505#else
506 return 0;
507#endif
508}
509
510/*
511 * mmap DMA memory.
512 *
513 * \param file_priv DRM file private.
514 * \param vma virtual memory area.
515 * \return zero on success or a negative number on failure.
516 *
517 * If the virtual memory area has no offset associated with it then it's a DMA
518 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
519 * checks that the restricted flag is not set, sets the virtual memory operations
520 * according to the mapping type and remaps the pages. Finally sets the file
521 * pointer and calls vm_open().
522 */
523static int drm_mmap_locked(struct file *filp, struct vm_area_struct *vma)
524{
525 struct drm_file *priv = filp->private_data;
526 struct drm_device *dev = priv->minor->dev;
527 struct drm_local_map *map = NULL;
528 resource_size_t offset = 0;
529 struct drm_hash_item *hash;
530
531 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
532 vma->vm_start, vma->vm_end, vma->vm_pgoff);
533
534 if (!priv->authenticated)
535 return -EACCES;
536
537 /* We check for "dma". On Apple's UniNorth, it's valid to have
538 * the AGP mapped at physical address 0
539 * --BenH.
540 */
541 if (!vma->vm_pgoff
542#if IS_ENABLED(CONFIG_AGP)
543 && (!dev->agp
544 || dev->agp->agp_info.device->vendor != PCI_VENDOR_ID_APPLE)
545#endif
546 )
547 return drm_mmap_dma(filp, vma);
548
549 if (drm_ht_find_item(&dev->map_hash, vma->vm_pgoff, &hash)) {
550 DRM_ERROR("Could not find map\n");
551 return -EINVAL;
552 }
553
554 map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
555 if (!map || ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN)))
556 return -EPERM;
557
558 /* Check for valid size. */
559 if (map->size < vma->vm_end - vma->vm_start)
560 return -EINVAL;
561
562 if (!capable(CAP_SYS_ADMIN) && (map->flags & _DRM_READ_ONLY)) {
563 vma->vm_flags &= ~(VM_WRITE | VM_MAYWRITE);
564#if defined(__i386__) || defined(__x86_64__)
565 pgprot_val(vma->vm_page_prot) &= ~_PAGE_RW;
566#else
567 /* Ye gads this is ugly. With more thought
568 we could move this up higher and use
569 `protection_map' instead. */
570 vma->vm_page_prot =
571 __pgprot(pte_val
572 (pte_wrprotect
573 (__pte(pgprot_val(vma->vm_page_prot)))));
574#endif
575 }
576
577 switch (map->type) {
578#if !defined(__arm__)
579 case _DRM_AGP:
580 if (dev->agp && dev->agp->cant_use_aperture) {
581 /*
582 * On some platforms we can't talk to bus dma address from the CPU, so for
583 * memory of type DRM_AGP, we'll deal with sorting out the real physical
584 * pages and mappings in fault()
585 */
586#if defined(__powerpc__)
587 vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
588#endif
589 vma->vm_ops = &drm_vm_ops;
590 break;
591 }
592 fallthrough; /* to _DRM_FRAME_BUFFER... */
593#endif
594 case _DRM_FRAME_BUFFER:
595 case _DRM_REGISTERS:
596 offset = drm_core_get_reg_ofs(dev);
597 vma->vm_page_prot = drm_io_prot(map, vma);
598 if (io_remap_pfn_range(vma, vma->vm_start,
599 (map->offset + offset) >> PAGE_SHIFT,
600 vma->vm_end - vma->vm_start,
601 vma->vm_page_prot))
602 return -EAGAIN;
603 DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx,"
604 " offset = 0x%llx\n",
605 map->type,
606 vma->vm_start, vma->vm_end, (unsigned long long)(map->offset + offset));
607
608 vma->vm_ops = &drm_vm_ops;
609 break;
610 case _DRM_CONSISTENT:
611 /* Consistent memory is really like shared memory. But
612 * it's allocated in a different way, so avoid fault */
613 if (remap_pfn_range(vma, vma->vm_start,
614 page_to_pfn(virt_to_page(map->handle)),
615 vma->vm_end - vma->vm_start, vma->vm_page_prot))
616 return -EAGAIN;
617 vma->vm_page_prot = drm_dma_prot(map->type, vma);
618 fallthrough; /* to _DRM_SHM */
619 case _DRM_SHM:
620 vma->vm_ops = &drm_vm_shm_ops;
621 vma->vm_private_data = (void *)map;
622 break;
623 case _DRM_SCATTER_GATHER:
624 vma->vm_ops = &drm_vm_sg_ops;
625 vma->vm_private_data = (void *)map;
626 vma->vm_page_prot = drm_dma_prot(map->type, vma);
627 break;
628 default:
629 return -EINVAL; /* This should never happen. */
630 }
631 vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
632
633 drm_vm_open_locked(dev, vma);
634 return 0;
635}
636
637int drm_legacy_mmap(struct file *filp, struct vm_area_struct *vma)
638{
639 struct drm_file *priv = filp->private_data;
640 struct drm_device *dev = priv->minor->dev;
641 int ret;
642
643 if (drm_dev_is_unplugged(dev))
644 return -ENODEV;
645
646 mutex_lock(&dev->struct_mutex);
647 ret = drm_mmap_locked(filp, vma);
648 mutex_unlock(&dev->struct_mutex);
649
650 return ret;
651}
652EXPORT_SYMBOL(drm_legacy_mmap);
653
654#if IS_ENABLED(CONFIG_DRM_LEGACY)
655void drm_legacy_vma_flush(struct drm_device *dev)
656{
657 struct drm_vma_entry *vma, *vma_temp;
658
659 /* Clear vma list (only needed for legacy drivers) */
660 list_for_each_entry_safe(vma, vma_temp, &dev->vmalist, head) {
661 list_del(&vma->head);
662 kfree(vma);
663 }
664}
665#endif