Merge tag 'block-5.14-2021-08-20' of git://git.kernel.dk/linux-block
[platform/kernel/linux-rpi.git] / drivers / gpu / drm / drm_vm.c
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
57 struct drm_vma_entry {
58         struct list_head head;
59         struct vm_area_struct *vma;
60         pid_t pid;
61 };
62
63 static void drm_vm_open(struct vm_area_struct *vma);
64 static void drm_vm_close(struct vm_area_struct *vma);
65
66 static 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__)
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
89 static 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)
110 static 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         }
179 vm_fault_error:
180         return VM_FAULT_SIGBUS; /* Disallow mremap */
181 }
182 #else
183 static 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  */
199 static 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  */
230 static 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  */
299 static 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  */
334 static 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 */
362 static 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 */
369 static 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 */
376 static 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 */
383 static 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
389 static 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
405 static 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
415 static 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  */
440 static 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  */
460 static 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
501 static 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  */
523 static 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
637 int 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 }
652 EXPORT_SYMBOL(drm_legacy_mmap);
653
654 #if IS_ENABLED(CONFIG_DRM_LEGACY)
655 void 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