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