xref: /openbmc/linux/drivers/gpu/drm/drm_vm.c (revision 1c71222e)
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 
drm_io_prot(struct drm_local_map * map,struct vm_area_struct * vma)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__) || defined(__loongarch__)
73 	if (map->type == _DRM_REGISTERS && !(map->flags & _DRM_WRITE_COMBINING))
74 		tmp = pgprot_noncached(tmp);
75 	else
76 		tmp = pgprot_writecombine(tmp);
77 #elif defined(__ia64__)
78 	if (efi_range_is_wc(vma->vm_start, vma->vm_end -
79 				    vma->vm_start))
80 		tmp = pgprot_writecombine(tmp);
81 	else
82 		tmp = pgprot_noncached(tmp);
83 #elif defined(__sparc__) || defined(__arm__)
84 	tmp = pgprot_noncached(tmp);
85 #endif
86 	return tmp;
87 }
88 
drm_dma_prot(uint32_t map_type,struct vm_area_struct * vma)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)
drm_vm_fault(struct vm_fault * vmf)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
drm_vm_fault(struct vm_fault * vmf)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  */
drm_vm_shm_fault(struct vm_fault * vmf)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  */
drm_vm_shm_close(struct vm_area_struct * vma)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  */
drm_vm_dma_fault(struct vm_fault * vmf)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  */
drm_vm_sg_fault(struct vm_fault * vmf)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 
drm_vm_open_locked(struct drm_device * dev,struct vm_area_struct * vma)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 
drm_vm_open(struct vm_area_struct * vma)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 
drm_vm_close_locked(struct drm_device * dev,struct vm_area_struct * vma)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  */
drm_vm_close(struct vm_area_struct * vma)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  */
drm_mmap_dma(struct file * filp,struct vm_area_struct * vma)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 		vm_flags_clear(vma, 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 	vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
496 
497 	drm_vm_open_locked(dev, vma);
498 	return 0;
499 }
500 
drm_core_get_reg_ofs(struct drm_device * dev)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  */
drm_mmap_locked(struct file * filp,struct vm_area_struct * vma)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 		vm_flags_clear(vma, 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 	vm_flags_set(vma, VM_DONTEXPAND | VM_DONTDUMP);
632 
633 	drm_vm_open_locked(dev, vma);
634 	return 0;
635 }
636 
drm_legacy_mmap(struct file * filp,struct vm_area_struct * vma)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)
drm_legacy_vma_flush(struct drm_device * dev)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
666