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