3 * Memory mapping for DRM
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Gareth Hughes <gareth@valinux.com>
10 * Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com
12 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
13 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
14 * All Rights Reserved.
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:
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
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.
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>
43 #include <linux/efi.h>
44 #include <linux/slab.h>
46 #include <linux/mem_encrypt.h>
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>
56 #include "drm_internal.h"
57 #include "drm_legacy.h"
59 struct drm_vma_entry
{
60 struct list_head head
;
61 struct vm_area_struct
*vma
;
65 static void drm_vm_open(struct vm_area_struct
*vma
);
66 static void drm_vm_close(struct vm_area_struct
*vma
);
68 static pgprot_t
drm_io_prot(struct drm_local_map
*map
,
69 struct vm_area_struct
*vma
)
71 pgprot_t tmp
= vm_get_page_prot(vma
->vm_flags
);
73 #if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__) || \
75 if (map
->type
== _DRM_REGISTERS
&& !(map
->flags
& _DRM_WRITE_COMBINING
))
76 tmp
= pgprot_noncached(tmp
);
78 tmp
= pgprot_writecombine(tmp
);
79 #elif defined(__ia64__)
80 if (efi_range_is_wc(vma
->vm_start
, vma
->vm_end
-
82 tmp
= pgprot_writecombine(tmp
);
84 tmp
= pgprot_noncached(tmp
);
85 #elif defined(__sparc__) || defined(__arm__)
86 tmp
= pgprot_noncached(tmp
);
91 static pgprot_t
drm_dma_prot(uint32_t map_type
, struct vm_area_struct
*vma
)
93 pgprot_t tmp
= vm_get_page_prot(vma
->vm_flags
);
95 #if defined(__powerpc__) && defined(CONFIG_NOT_COHERENT_CACHE)
96 tmp
= pgprot_noncached_wc(tmp
);
102 * \c fault method for AGP virtual memory.
104 * \param vma virtual memory area.
105 * \param address access address.
106 * \return pointer to the page structure.
108 * Find the right map and if it's AGP memory find the real physical page to
109 * map, get the page, increment the use count and return it.
111 #if IS_ENABLED(CONFIG_AGP)
112 static vm_fault_t
drm_vm_fault(struct vm_fault
*vmf
)
114 struct vm_area_struct
*vma
= vmf
->vma
;
115 struct drm_file
*priv
= vma
->vm_file
->private_data
;
116 struct drm_device
*dev
= priv
->minor
->dev
;
117 struct drm_local_map
*map
= NULL
;
118 struct drm_map_list
*r_list
;
119 struct drm_hash_item
*hash
;
127 if (!dev
->agp
|| !dev
->agp
->cant_use_aperture
)
130 if (drm_ht_find_item(&dev
->map_hash
, vma
->vm_pgoff
, &hash
))
133 r_list
= drm_hash_entry(hash
, struct drm_map_list
, hash
);
136 if (map
&& map
->type
== _DRM_AGP
) {
138 * Using vm_pgoff as a selector forces us to use this unusual
141 resource_size_t offset
= vmf
->address
- vma
->vm_start
;
142 resource_size_t baddr
= map
->offset
+ offset
;
143 struct drm_agp_mem
*agpmem
;
148 * Adjust to a bus-relative address
150 baddr
-= dev
->hose
->mem_space
->start
;
154 * It's AGP memory - find the real physical page to map
156 list_for_each_entry(agpmem
, &dev
->agp
->memory
, head
) {
157 if (agpmem
->bound
<= baddr
&&
158 agpmem
->bound
+ agpmem
->pages
* PAGE_SIZE
> baddr
)
162 if (&agpmem
->head
== &dev
->agp
->memory
)
166 * Get the page, inc the use count, and return it
168 offset
= (baddr
- agpmem
->bound
) >> PAGE_SHIFT
;
169 page
= agpmem
->memory
->pages
[offset
];
174 ("baddr = 0x%llx page = 0x%p, offset = 0x%llx, count=%d\n",
175 (unsigned long long)baddr
,
176 agpmem
->memory
->pages
[offset
],
177 (unsigned long long)offset
,
182 return VM_FAULT_SIGBUS
; /* Disallow mremap */
185 static vm_fault_t
drm_vm_fault(struct vm_fault
*vmf
)
187 return VM_FAULT_SIGBUS
;
192 * \c nopage method for shared virtual memory.
194 * \param vma virtual memory area.
195 * \param address access address.
196 * \return pointer to the page structure.
198 * Get the mapping, find the real physical page to map, get the page, and
201 static vm_fault_t
drm_vm_shm_fault(struct vm_fault
*vmf
)
203 struct vm_area_struct
*vma
= vmf
->vma
;
204 struct drm_local_map
*map
= vma
->vm_private_data
;
205 unsigned long offset
;
210 return VM_FAULT_SIGBUS
; /* Nothing allocated */
212 offset
= vmf
->address
- vma
->vm_start
;
213 i
= (unsigned long)map
->handle
+ offset
;
214 page
= vmalloc_to_page((void *)i
);
216 return VM_FAULT_SIGBUS
;
220 DRM_DEBUG("shm_fault 0x%lx\n", offset
);
225 * \c close method for shared virtual memory.
227 * \param vma virtual memory area.
229 * Deletes map information if we are the last
230 * person to close a mapping and it's not in the global maplist.
232 static void drm_vm_shm_close(struct vm_area_struct
*vma
)
234 struct drm_file
*priv
= vma
->vm_file
->private_data
;
235 struct drm_device
*dev
= priv
->minor
->dev
;
236 struct drm_vma_entry
*pt
, *temp
;
237 struct drm_local_map
*map
;
238 struct drm_map_list
*r_list
;
241 DRM_DEBUG("0x%08lx,0x%08lx\n",
242 vma
->vm_start
, vma
->vm_end
- vma
->vm_start
);
244 map
= vma
->vm_private_data
;
246 mutex_lock(&dev
->struct_mutex
);
247 list_for_each_entry_safe(pt
, temp
, &dev
->vmalist
, head
) {
248 if (pt
->vma
->vm_private_data
== map
)
250 if (pt
->vma
== vma
) {
256 /* We were the only map that was found */
257 if (found_maps
== 1 && map
->flags
& _DRM_REMOVABLE
) {
258 /* Check to see if we are in the maplist, if we are not, then
259 * we delete this mappings information.
262 list_for_each_entry(r_list
, &dev
->maplist
, head
) {
263 if (r_list
->map
== map
)
270 case _DRM_FRAME_BUFFER
:
271 arch_phys_wc_del(map
->mtrr
);
272 iounmap(map
->handle
);
278 case _DRM_SCATTER_GATHER
:
280 case _DRM_CONSISTENT
:
281 dma_free_coherent(&dev
->pdev
->dev
,
290 mutex_unlock(&dev
->struct_mutex
);
294 * \c fault method for DMA virtual memory.
296 * \param address access address.
297 * \return pointer to the page structure.
299 * Determine the page number from the page offset and get it from drm_device_dma::pagelist.
301 static vm_fault_t
drm_vm_dma_fault(struct vm_fault
*vmf
)
303 struct vm_area_struct
*vma
= vmf
->vma
;
304 struct drm_file
*priv
= vma
->vm_file
->private_data
;
305 struct drm_device
*dev
= priv
->minor
->dev
;
306 struct drm_device_dma
*dma
= dev
->dma
;
307 unsigned long offset
;
308 unsigned long page_nr
;
312 return VM_FAULT_SIGBUS
; /* Error */
314 return VM_FAULT_SIGBUS
; /* Nothing allocated */
316 offset
= vmf
->address
- vma
->vm_start
;
317 /* vm_[pg]off[set] should be 0 */
318 page_nr
= offset
>> PAGE_SHIFT
; /* page_nr could just be vmf->pgoff */
319 page
= virt_to_page((void *)dma
->pagelist
[page_nr
]);
324 DRM_DEBUG("dma_fault 0x%lx (page %lu)\n", offset
, page_nr
);
329 * \c fault method for scatter-gather virtual memory.
331 * \param address access address.
332 * \return pointer to the page structure.
334 * Determine the map offset from the page offset and get it from drm_sg_mem::pagelist.
336 static vm_fault_t
drm_vm_sg_fault(struct vm_fault
*vmf
)
338 struct vm_area_struct
*vma
= vmf
->vma
;
339 struct drm_local_map
*map
= vma
->vm_private_data
;
340 struct drm_file
*priv
= vma
->vm_file
->private_data
;
341 struct drm_device
*dev
= priv
->minor
->dev
;
342 struct drm_sg_mem
*entry
= dev
->sg
;
343 unsigned long offset
;
344 unsigned long map_offset
;
345 unsigned long page_offset
;
349 return VM_FAULT_SIGBUS
; /* Error */
350 if (!entry
->pagelist
)
351 return VM_FAULT_SIGBUS
; /* Nothing allocated */
353 offset
= vmf
->address
- vma
->vm_start
;
354 map_offset
= map
->offset
- (unsigned long)dev
->sg
->virtual;
355 page_offset
= (offset
>> PAGE_SHIFT
) + (map_offset
>> PAGE_SHIFT
);
356 page
= entry
->pagelist
[page_offset
];
363 /** AGP virtual memory operations */
364 static const struct vm_operations_struct drm_vm_ops
= {
365 .fault
= drm_vm_fault
,
367 .close
= drm_vm_close
,
370 /** Shared virtual memory operations */
371 static const struct vm_operations_struct drm_vm_shm_ops
= {
372 .fault
= drm_vm_shm_fault
,
374 .close
= drm_vm_shm_close
,
377 /** DMA virtual memory operations */
378 static const struct vm_operations_struct drm_vm_dma_ops
= {
379 .fault
= drm_vm_dma_fault
,
381 .close
= drm_vm_close
,
384 /** Scatter-gather virtual memory operations */
385 static const struct vm_operations_struct drm_vm_sg_ops
= {
386 .fault
= drm_vm_sg_fault
,
388 .close
= drm_vm_close
,
391 static void drm_vm_open_locked(struct drm_device
*dev
,
392 struct vm_area_struct
*vma
)
394 struct drm_vma_entry
*vma_entry
;
396 DRM_DEBUG("0x%08lx,0x%08lx\n",
397 vma
->vm_start
, vma
->vm_end
- vma
->vm_start
);
399 vma_entry
= kmalloc(sizeof(*vma_entry
), GFP_KERNEL
);
401 vma_entry
->vma
= vma
;
402 vma_entry
->pid
= current
->pid
;
403 list_add(&vma_entry
->head
, &dev
->vmalist
);
407 static void drm_vm_open(struct vm_area_struct
*vma
)
409 struct drm_file
*priv
= vma
->vm_file
->private_data
;
410 struct drm_device
*dev
= priv
->minor
->dev
;
412 mutex_lock(&dev
->struct_mutex
);
413 drm_vm_open_locked(dev
, vma
);
414 mutex_unlock(&dev
->struct_mutex
);
417 static void drm_vm_close_locked(struct drm_device
*dev
,
418 struct vm_area_struct
*vma
)
420 struct drm_vma_entry
*pt
, *temp
;
422 DRM_DEBUG("0x%08lx,0x%08lx\n",
423 vma
->vm_start
, vma
->vm_end
- vma
->vm_start
);
425 list_for_each_entry_safe(pt
, temp
, &dev
->vmalist
, head
) {
426 if (pt
->vma
== vma
) {
435 * \c close method for all virtual memory types.
437 * \param vma virtual memory area.
439 * Search the \p vma private data entry in drm_device::vmalist, unlink it, and
442 static void drm_vm_close(struct vm_area_struct
*vma
)
444 struct drm_file
*priv
= vma
->vm_file
->private_data
;
445 struct drm_device
*dev
= priv
->minor
->dev
;
447 mutex_lock(&dev
->struct_mutex
);
448 drm_vm_close_locked(dev
, vma
);
449 mutex_unlock(&dev
->struct_mutex
);
455 * \param file_priv DRM file private.
456 * \param vma virtual memory area.
457 * \return zero on success or a negative number on failure.
459 * Sets the virtual memory area operations structure to vm_dma_ops, the file
460 * pointer, and calls vm_open().
462 static int drm_mmap_dma(struct file
*filp
, struct vm_area_struct
*vma
)
464 struct drm_file
*priv
= filp
->private_data
;
465 struct drm_device
*dev
;
466 struct drm_device_dma
*dma
;
467 unsigned long length
= vma
->vm_end
- vma
->vm_start
;
469 dev
= priv
->minor
->dev
;
471 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
472 vma
->vm_start
, vma
->vm_end
, vma
->vm_pgoff
);
474 /* Length must match exact page count */
475 if (!dma
|| (length
>> PAGE_SHIFT
) != dma
->page_count
) {
479 if (!capable(CAP_SYS_ADMIN
) &&
480 (dma
->flags
& _DRM_DMA_USE_PCI_RO
)) {
481 vma
->vm_flags
&= ~(VM_WRITE
| VM_MAYWRITE
);
482 #if defined(__i386__) || defined(__x86_64__)
483 pgprot_val(vma
->vm_page_prot
) &= ~_PAGE_RW
;
485 /* Ye gads this is ugly. With more thought
486 we could move this up higher and use
487 `protection_map' instead. */
491 (__pte(pgprot_val(vma
->vm_page_prot
)))));
495 vma
->vm_ops
= &drm_vm_dma_ops
;
497 vma
->vm_flags
|= VM_DONTEXPAND
| VM_DONTDUMP
;
499 drm_vm_open_locked(dev
, vma
);
503 static resource_size_t
drm_core_get_reg_ofs(struct drm_device
*dev
)
506 return dev
->hose
->dense_mem_base
;
515 * \param file_priv DRM file private.
516 * \param vma virtual memory area.
517 * \return zero on success or a negative number on failure.
519 * If the virtual memory area has no offset associated with it then it's a DMA
520 * area, so calls mmap_dma(). Otherwise searches the map in drm_device::maplist,
521 * checks that the restricted flag is not set, sets the virtual memory operations
522 * according to the mapping type and remaps the pages. Finally sets the file
523 * pointer and calls vm_open().
525 static int drm_mmap_locked(struct file
*filp
, struct vm_area_struct
*vma
)
527 struct drm_file
*priv
= filp
->private_data
;
528 struct drm_device
*dev
= priv
->minor
->dev
;
529 struct drm_local_map
*map
= NULL
;
530 resource_size_t offset
= 0;
531 struct drm_hash_item
*hash
;
533 DRM_DEBUG("start = 0x%lx, end = 0x%lx, page offset = 0x%lx\n",
534 vma
->vm_start
, vma
->vm_end
, vma
->vm_pgoff
);
536 if (!priv
->authenticated
)
539 /* We check for "dma". On Apple's UniNorth, it's valid to have
540 * the AGP mapped at physical address 0
544 #if IS_ENABLED(CONFIG_AGP)
546 || dev
->agp
->agp_info
.device
->vendor
!= PCI_VENDOR_ID_APPLE
)
549 return drm_mmap_dma(filp
, vma
);
551 if (drm_ht_find_item(&dev
->map_hash
, vma
->vm_pgoff
, &hash
)) {
552 DRM_ERROR("Could not find map\n");
556 map
= drm_hash_entry(hash
, struct drm_map_list
, hash
)->map
;
557 if (!map
|| ((map
->flags
& _DRM_RESTRICTED
) && !capable(CAP_SYS_ADMIN
)))
560 /* Check for valid size. */
561 if (map
->size
< vma
->vm_end
- vma
->vm_start
)
564 if (!capable(CAP_SYS_ADMIN
) && (map
->flags
& _DRM_READ_ONLY
)) {
565 vma
->vm_flags
&= ~(VM_WRITE
| VM_MAYWRITE
);
566 #if defined(__i386__) || defined(__x86_64__)
567 pgprot_val(vma
->vm_page_prot
) &= ~_PAGE_RW
;
569 /* Ye gads this is ugly. With more thought
570 we could move this up higher and use
571 `protection_map' instead. */
575 (__pte(pgprot_val(vma
->vm_page_prot
)))));
580 #if !defined(__arm__)
582 if (dev
->agp
&& dev
->agp
->cant_use_aperture
) {
584 * On some platforms we can't talk to bus dma address from the CPU, so for
585 * memory of type DRM_AGP, we'll deal with sorting out the real physical
586 * pages and mappings in fault()
588 #if defined(__powerpc__)
589 vma
->vm_page_prot
= pgprot_noncached(vma
->vm_page_prot
);
591 vma
->vm_ops
= &drm_vm_ops
;
594 fallthrough
; /* to _DRM_FRAME_BUFFER... */
596 case _DRM_FRAME_BUFFER
:
598 offset
= drm_core_get_reg_ofs(dev
);
599 vma
->vm_page_prot
= drm_io_prot(map
, vma
);
600 if (io_remap_pfn_range(vma
, vma
->vm_start
,
601 (map
->offset
+ offset
) >> PAGE_SHIFT
,
602 vma
->vm_end
- vma
->vm_start
,
605 DRM_DEBUG(" Type = %d; start = 0x%lx, end = 0x%lx,"
606 " offset = 0x%llx\n",
608 vma
->vm_start
, vma
->vm_end
, (unsigned long long)(map
->offset
+ offset
));
610 vma
->vm_ops
= &drm_vm_ops
;
612 case _DRM_CONSISTENT
:
613 /* Consistent memory is really like shared memory. But
614 * it's allocated in a different way, so avoid fault */
615 if (remap_pfn_range(vma
, vma
->vm_start
,
616 page_to_pfn(virt_to_page(map
->handle
)),
617 vma
->vm_end
- vma
->vm_start
, vma
->vm_page_prot
))
619 vma
->vm_page_prot
= drm_dma_prot(map
->type
, vma
);
620 fallthrough
; /* to _DRM_SHM */
622 vma
->vm_ops
= &drm_vm_shm_ops
;
623 vma
->vm_private_data
= (void *)map
;
625 case _DRM_SCATTER_GATHER
:
626 vma
->vm_ops
= &drm_vm_sg_ops
;
627 vma
->vm_private_data
= (void *)map
;
628 vma
->vm_page_prot
= drm_dma_prot(map
->type
, vma
);
631 return -EINVAL
; /* This should never happen. */
633 vma
->vm_flags
|= VM_DONTEXPAND
| VM_DONTDUMP
;
635 drm_vm_open_locked(dev
, vma
);
639 int drm_legacy_mmap(struct file
*filp
, struct vm_area_struct
*vma
)
641 struct drm_file
*priv
= filp
->private_data
;
642 struct drm_device
*dev
= priv
->minor
->dev
;
645 if (drm_dev_is_unplugged(dev
))
648 mutex_lock(&dev
->struct_mutex
);
649 ret
= drm_mmap_locked(filp
, vma
);
650 mutex_unlock(&dev
->struct_mutex
);
654 EXPORT_SYMBOL(drm_legacy_mmap
);
656 #if IS_ENABLED(CONFIG_DRM_LEGACY)
657 void drm_legacy_vma_flush(struct drm_device
*dev
)
659 struct drm_vma_entry
*vma
, *vma_temp
;
661 /* Clear vma list (only needed for legacy drivers) */
662 list_for_each_entry_safe(vma
, vma_temp
, &dev
->vmalist
, head
) {
663 list_del(&vma
->head
);