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