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1/*
2 * Copyright © 2008 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 *
26 */
27
28#include <linux/types.h>
29#include <linux/slab.h>
30#include <linux/mm.h>
31#include <linux/uaccess.h>
32#include <linux/fs.h>
33#include <linux/file.h>
34#include <linux/module.h>
35#include <linux/mman.h>
36#include <linux/pagemap.h>
37#include <linux/shmem_fs.h>
38#include "drmP.h"
39
40/** @file drm_gem.c
41 *
42 * This file provides some of the base ioctls and library routines for
43 * the graphics memory manager implemented by each device driver.
44 *
45 * Because various devices have different requirements in terms of
46 * synchronization and migration strategies, implementing that is left up to
47 * the driver, and all that the general API provides should be generic --
48 * allocating objects, reading/writing data with the cpu, freeing objects.
49 * Even there, platform-dependent optimizations for reading/writing data with
50 * the CPU mean we'll likely hook those out to driver-specific calls. However,
51 * the DRI2 implementation wants to have at least allocate/mmap be generic.
52 *
53 * The goal was to have swap-backed object allocation managed through
54 * struct file. However, file descriptors as handles to a struct file have
55 * two major failings:
56 * - Process limits prevent more than 1024 or so being used at a time by
57 * default.
58 * - Inability to allocate high fds will aggravate the X Server's select()
59 * handling, and likely that of many GL client applications as well.
60 *
61 * This led to a plan of using our own integer IDs (called handles, following
62 * DRM terminology) to mimic fds, and implement the fd syscalls we need as
63 * ioctls. The objects themselves will still include the struct file so
64 * that we can transition to fds if the required kernel infrastructure shows
65 * up at a later date, and as our interface with shmfs for memory allocation.
66 */
67
68/*
69 * We make up offsets for buffer objects so we can recognize them at
70 * mmap time.
71 */
72
73/* pgoff in mmap is an unsigned long, so we need to make sure that
74 * the faked up offset will fit
75 */
76
77#if BITS_PER_LONG == 64
78#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
79#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16)
80#else
81#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
82#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
83#endif
84
85/**
86 * Initialize the GEM device fields
87 */
88
89int
90drm_gem_init(struct drm_device *dev)
91{
92 struct drm_gem_mm *mm;
93
94 spin_lock_init(&dev->object_name_lock);
95 idr_init(&dev->object_name_idr);
96
97 mm = kzalloc(sizeof(struct drm_gem_mm), GFP_KERNEL);
98 if (!mm) {
99 DRM_ERROR("out of memory\n");
100 return -ENOMEM;
101 }
102
103 dev->mm_private = mm;
104
105 if (drm_ht_create(&mm->offset_hash, 12)) {
106 kfree(mm);
107 return -ENOMEM;
108 }
109
110 if (drm_mm_init(&mm->offset_manager, DRM_FILE_PAGE_OFFSET_START,
111 DRM_FILE_PAGE_OFFSET_SIZE)) {
112 drm_ht_remove(&mm->offset_hash);
113 kfree(mm);
114 return -ENOMEM;
115 }
116
117 return 0;
118}
119
120void
121drm_gem_destroy(struct drm_device *dev)
122{
123 struct drm_gem_mm *mm = dev->mm_private;
124
125 drm_mm_takedown(&mm->offset_manager);
126 drm_ht_remove(&mm->offset_hash);
127 kfree(mm);
128 dev->mm_private = NULL;
129}
130
131/**
132 * Initialize an already allocated GEM object of the specified size with
133 * shmfs backing store.
134 */
135int drm_gem_object_init(struct drm_device *dev,
136 struct drm_gem_object *obj, size_t size)
137{
138 BUG_ON((size & (PAGE_SIZE - 1)) != 0);
139
140 obj->dev = dev;
141 obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
142 if (IS_ERR(obj->filp))
143 return -ENOMEM;
144
145 kref_init(&obj->refcount);
146 atomic_set(&obj->handle_count, 0);
147 obj->size = size;
148
149 return 0;
150}
151EXPORT_SYMBOL(drm_gem_object_init);
152
153/**
154 * Initialize an already allocated GEM object of the specified size with
155 * no GEM provided backing store. Instead the caller is responsible for
156 * backing the object and handling it.
157 */
158int drm_gem_private_object_init(struct drm_device *dev,
159 struct drm_gem_object *obj, size_t size)
160{
161 BUG_ON((size & (PAGE_SIZE - 1)) != 0);
162
163 obj->dev = dev;
164 obj->filp = NULL;
165
166 kref_init(&obj->refcount);
167 atomic_set(&obj->handle_count, 0);
168 obj->size = size;
169
170 return 0;
171}
172EXPORT_SYMBOL(drm_gem_private_object_init);
173
174/**
175 * Allocate a GEM object of the specified size with shmfs backing store
176 */
177struct drm_gem_object *
178drm_gem_object_alloc(struct drm_device *dev, size_t size)
179{
180 struct drm_gem_object *obj;
181
182 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
183 if (!obj)
184 goto free;
185
186 if (drm_gem_object_init(dev, obj, size) != 0)
187 goto free;
188
189 if (dev->driver->gem_init_object != NULL &&
190 dev->driver->gem_init_object(obj) != 0) {
191 goto fput;
192 }
193 return obj;
194fput:
195 /* Object_init mangles the global counters - readjust them. */
196 fput(obj->filp);
197free:
198 kfree(obj);
199 return NULL;
200}
201EXPORT_SYMBOL(drm_gem_object_alloc);
202
203/**
204 * Removes the mapping from handle to filp for this object.
205 */
206int
207drm_gem_handle_delete(struct drm_file *filp, u32 handle)
208{
209 struct drm_device *dev;
210 struct drm_gem_object *obj;
211
212 /* This is gross. The idr system doesn't let us try a delete and
213 * return an error code. It just spews if you fail at deleting.
214 * So, we have to grab a lock around finding the object and then
215 * doing the delete on it and dropping the refcount, or the user
216 * could race us to double-decrement the refcount and cause a
217 * use-after-free later. Given the frequency of our handle lookups,
218 * we may want to use ida for number allocation and a hash table
219 * for the pointers, anyway.
220 */
221 spin_lock(&filp->table_lock);
222
223 /* Check if we currently have a reference on the object */
224 obj = idr_find(&filp->object_idr, handle);
225 if (obj == NULL) {
226 spin_unlock(&filp->table_lock);
227 return -EINVAL;
228 }
229 dev = obj->dev;
230
231 /* Release reference and decrement refcount. */
232 idr_remove(&filp->object_idr, handle);
233 spin_unlock(&filp->table_lock);
234
235 if (dev->driver->gem_close_object)
236 dev->driver->gem_close_object(obj, filp);
237 drm_gem_object_handle_unreference_unlocked(obj);
238
239 return 0;
240}
241EXPORT_SYMBOL(drm_gem_handle_delete);
242
243/**
244 * Create a handle for this object. This adds a handle reference
245 * to the object, which includes a regular reference count. Callers
246 * will likely want to dereference the object afterwards.
247 */
248int
249drm_gem_handle_create(struct drm_file *file_priv,
250 struct drm_gem_object *obj,
251 u32 *handlep)
252{
253 struct drm_device *dev = obj->dev;
254 int ret;
255
256 /*
257 * Get the user-visible handle using idr.
258 */
259again:
260 /* ensure there is space available to allocate a handle */
261 if (idr_pre_get(&file_priv->object_idr, GFP_KERNEL) == 0)
262 return -ENOMEM;
263
264 /* do the allocation under our spinlock */
265 spin_lock(&file_priv->table_lock);
266 ret = idr_get_new_above(&file_priv->object_idr, obj, 1, (int *)handlep);
267 spin_unlock(&file_priv->table_lock);
268 if (ret == -EAGAIN)
269 goto again;
270
271 if (ret != 0)
272 return ret;
273
274 drm_gem_object_handle_reference(obj);
275
276 if (dev->driver->gem_open_object) {
277 ret = dev->driver->gem_open_object(obj, file_priv);
278 if (ret) {
279 drm_gem_handle_delete(file_priv, *handlep);
280 return ret;
281 }
282 }
283
284 return 0;
285}
286EXPORT_SYMBOL(drm_gem_handle_create);
287
288/** Returns a reference to the object named by the handle. */
289struct drm_gem_object *
290drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp,
291 u32 handle)
292{
293 struct drm_gem_object *obj;
294
295 spin_lock(&filp->table_lock);
296
297 /* Check if we currently have a reference on the object */
298 obj = idr_find(&filp->object_idr, handle);
299 if (obj == NULL) {
300 spin_unlock(&filp->table_lock);
301 return NULL;
302 }
303
304 drm_gem_object_reference(obj);
305
306 spin_unlock(&filp->table_lock);
307
308 return obj;
309}
310EXPORT_SYMBOL(drm_gem_object_lookup);
311
312/**
313 * Releases the handle to an mm object.
314 */
315int
316drm_gem_close_ioctl(struct drm_device *dev, void *data,
317 struct drm_file *file_priv)
318{
319 struct drm_gem_close *args = data;
320 int ret;
321
322 if (!(dev->driver->driver_features & DRIVER_GEM))
323 return -ENODEV;
324
325 ret = drm_gem_handle_delete(file_priv, args->handle);
326
327 return ret;
328}
329
330/**
331 * Create a global name for an object, returning the name.
332 *
333 * Note that the name does not hold a reference; when the object
334 * is freed, the name goes away.
335 */
336int
337drm_gem_flink_ioctl(struct drm_device *dev, void *data,
338 struct drm_file *file_priv)
339{
340 struct drm_gem_flink *args = data;
341 struct drm_gem_object *obj;
342 int ret;
343
344 if (!(dev->driver->driver_features & DRIVER_GEM))
345 return -ENODEV;
346
347 obj = drm_gem_object_lookup(dev, file_priv, args->handle);
348 if (obj == NULL)
349 return -ENOENT;
350
351again:
352 if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0) {
353 ret = -ENOMEM;
354 goto err;
355 }
356
357 spin_lock(&dev->object_name_lock);
358 if (!obj->name) {
359 ret = idr_get_new_above(&dev->object_name_idr, obj, 1,
360 &obj->name);
361 args->name = (uint64_t) obj->name;
362 spin_unlock(&dev->object_name_lock);
363
364 if (ret == -EAGAIN)
365 goto again;
366
367 if (ret != 0)
368 goto err;
369
370 /* Allocate a reference for the name table. */
371 drm_gem_object_reference(obj);
372 } else {
373 args->name = (uint64_t) obj->name;
374 spin_unlock(&dev->object_name_lock);
375 ret = 0;
376 }
377
378err:
379 drm_gem_object_unreference_unlocked(obj);
380 return ret;
381}
382
383/**
384 * Open an object using the global name, returning a handle and the size.
385 *
386 * This handle (of course) holds a reference to the object, so the object
387 * will not go away until the handle is deleted.
388 */
389int
390drm_gem_open_ioctl(struct drm_device *dev, void *data,
391 struct drm_file *file_priv)
392{
393 struct drm_gem_open *args = data;
394 struct drm_gem_object *obj;
395 int ret;
396 u32 handle;
397
398 if (!(dev->driver->driver_features & DRIVER_GEM))
399 return -ENODEV;
400
401 spin_lock(&dev->object_name_lock);
402 obj = idr_find(&dev->object_name_idr, (int) args->name);
403 if (obj)
404 drm_gem_object_reference(obj);
405 spin_unlock(&dev->object_name_lock);
406 if (!obj)
407 return -ENOENT;
408
409 ret = drm_gem_handle_create(file_priv, obj, &handle);
410 drm_gem_object_unreference_unlocked(obj);
411 if (ret)
412 return ret;
413
414 args->handle = handle;
415 args->size = obj->size;
416
417 return 0;
418}
419
420/**
421 * Called at device open time, sets up the structure for handling refcounting
422 * of mm objects.
423 */
424void
425drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
426{
427 idr_init(&file_private->object_idr);
428 spin_lock_init(&file_private->table_lock);
429}
430
431/**
432 * Called at device close to release the file's
433 * handle references on objects.
434 */
435static int
436drm_gem_object_release_handle(int id, void *ptr, void *data)
437{
438 struct drm_file *file_priv = data;
439 struct drm_gem_object *obj = ptr;
440 struct drm_device *dev = obj->dev;
441
442 if (dev->driver->gem_close_object)
443 dev->driver->gem_close_object(obj, file_priv);
444
445 drm_gem_object_handle_unreference_unlocked(obj);
446
447 return 0;
448}
449
450/**
451 * Called at close time when the filp is going away.
452 *
453 * Releases any remaining references on objects by this filp.
454 */
455void
456drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
457{
458 idr_for_each(&file_private->object_idr,
459 &drm_gem_object_release_handle, file_private);
460
461 idr_remove_all(&file_private->object_idr);
462 idr_destroy(&file_private->object_idr);
463}
464
465void
466drm_gem_object_release(struct drm_gem_object *obj)
467{
468 if (obj->filp)
469 fput(obj->filp);
470}
471EXPORT_SYMBOL(drm_gem_object_release);
472
473/**
474 * Called after the last reference to the object has been lost.
475 * Must be called holding struct_ mutex
476 *
477 * Frees the object
478 */
479void
480drm_gem_object_free(struct kref *kref)
481{
482 struct drm_gem_object *obj = (struct drm_gem_object *) kref;
483 struct drm_device *dev = obj->dev;
484
485 BUG_ON(!mutex_is_locked(&dev->struct_mutex));
486
487 if (dev->driver->gem_free_object != NULL)
488 dev->driver->gem_free_object(obj);
489}
490EXPORT_SYMBOL(drm_gem_object_free);
491
492static void drm_gem_object_ref_bug(struct kref *list_kref)
493{
494 BUG();
495}
496
497/**
498 * Called after the last handle to the object has been closed
499 *
500 * Removes any name for the object. Note that this must be
501 * called before drm_gem_object_free or we'll be touching
502 * freed memory
503 */
504void drm_gem_object_handle_free(struct drm_gem_object *obj)
505{
506 struct drm_device *dev = obj->dev;
507
508 /* Remove any name for this object */
509 spin_lock(&dev->object_name_lock);
510 if (obj->name) {
511 idr_remove(&dev->object_name_idr, obj->name);
512 obj->name = 0;
513 spin_unlock(&dev->object_name_lock);
514 /*
515 * The object name held a reference to this object, drop
516 * that now.
517 *
518 * This cannot be the last reference, since the handle holds one too.
519 */
520 kref_put(&obj->refcount, drm_gem_object_ref_bug);
521 } else
522 spin_unlock(&dev->object_name_lock);
523
524}
525EXPORT_SYMBOL(drm_gem_object_handle_free);
526
527void drm_gem_vm_open(struct vm_area_struct *vma)
528{
529 struct drm_gem_object *obj = vma->vm_private_data;
530
531 drm_gem_object_reference(obj);
532
533 mutex_lock(&obj->dev->struct_mutex);
534 drm_vm_open_locked(vma);
535 mutex_unlock(&obj->dev->struct_mutex);
536}
537EXPORT_SYMBOL(drm_gem_vm_open);
538
539void drm_gem_vm_close(struct vm_area_struct *vma)
540{
541 struct drm_gem_object *obj = vma->vm_private_data;
542 struct drm_device *dev = obj->dev;
543
544 mutex_lock(&dev->struct_mutex);
545 drm_vm_close_locked(vma);
546 drm_gem_object_unreference(obj);
547 mutex_unlock(&dev->struct_mutex);
548}
549EXPORT_SYMBOL(drm_gem_vm_close);
550
551
552/**
553 * drm_gem_mmap - memory map routine for GEM objects
554 * @filp: DRM file pointer
555 * @vma: VMA for the area to be mapped
556 *
557 * If a driver supports GEM object mapping, mmap calls on the DRM file
558 * descriptor will end up here.
559 *
560 * If we find the object based on the offset passed in (vma->vm_pgoff will
561 * contain the fake offset we created when the GTT map ioctl was called on
562 * the object), we set up the driver fault handler so that any accesses
563 * to the object can be trapped, to perform migration, GTT binding, surface
564 * register allocation, or performance monitoring.
565 */
566int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
567{
568 struct drm_file *priv = filp->private_data;
569 struct drm_device *dev = priv->minor->dev;
570 struct drm_gem_mm *mm = dev->mm_private;
571 struct drm_local_map *map = NULL;
572 struct drm_gem_object *obj;
573 struct drm_hash_item *hash;
574 int ret = 0;
575
576 mutex_lock(&dev->struct_mutex);
577
578 if (drm_ht_find_item(&mm->offset_hash, vma->vm_pgoff, &hash)) {
579 mutex_unlock(&dev->struct_mutex);
580 return drm_mmap(filp, vma);
581 }
582
583 map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
584 if (!map ||
585 ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) {
586 ret = -EPERM;
587 goto out_unlock;
588 }
589
590 /* Check for valid size. */
591 if (map->size < vma->vm_end - vma->vm_start) {
592 ret = -EINVAL;
593 goto out_unlock;
594 }
595
596 obj = map->handle;
597 if (!obj->dev->driver->gem_vm_ops) {
598 ret = -EINVAL;
599 goto out_unlock;
600 }
601
602 vma->vm_flags |= VM_RESERVED | VM_IO | VM_PFNMAP | VM_DONTEXPAND;
603 vma->vm_ops = obj->dev->driver->gem_vm_ops;
604 vma->vm_private_data = map->handle;
605 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
606
607 /* Take a ref for this mapping of the object, so that the fault
608 * handler can dereference the mmap offset's pointer to the object.
609 * This reference is cleaned up by the corresponding vm_close
610 * (which should happen whether the vma was created by this call, or
611 * by a vm_open due to mremap or partial unmap or whatever).
612 */
613 drm_gem_object_reference(obj);
614
615 vma->vm_file = filp; /* Needed for drm_vm_open() */
616 drm_vm_open_locked(vma);
617
618out_unlock:
619 mutex_unlock(&dev->struct_mutex);
620
621 return ret;
622}
623EXPORT_SYMBOL(drm_gem_mmap);
1/*
2 * Copyright © 2008 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 *
26 */
27
28#include <linux/types.h>
29#include <linux/slab.h>
30#include <linux/mm.h>
31#include <linux/uaccess.h>
32#include <linux/fs.h>
33#include <linux/file.h>
34#include <linux/module.h>
35#include <linux/mman.h>
36#include <linux/pagemap.h>
37#include <linux/shmem_fs.h>
38#include <linux/dma-buf.h>
39#include <drm/drmP.h>
40#include <drm/drm_vma_manager.h>
41
42/** @file drm_gem.c
43 *
44 * This file provides some of the base ioctls and library routines for
45 * the graphics memory manager implemented by each device driver.
46 *
47 * Because various devices have different requirements in terms of
48 * synchronization and migration strategies, implementing that is left up to
49 * the driver, and all that the general API provides should be generic --
50 * allocating objects, reading/writing data with the cpu, freeing objects.
51 * Even there, platform-dependent optimizations for reading/writing data with
52 * the CPU mean we'll likely hook those out to driver-specific calls. However,
53 * the DRI2 implementation wants to have at least allocate/mmap be generic.
54 *
55 * The goal was to have swap-backed object allocation managed through
56 * struct file. However, file descriptors as handles to a struct file have
57 * two major failings:
58 * - Process limits prevent more than 1024 or so being used at a time by
59 * default.
60 * - Inability to allocate high fds will aggravate the X Server's select()
61 * handling, and likely that of many GL client applications as well.
62 *
63 * This led to a plan of using our own integer IDs (called handles, following
64 * DRM terminology) to mimic fds, and implement the fd syscalls we need as
65 * ioctls. The objects themselves will still include the struct file so
66 * that we can transition to fds if the required kernel infrastructure shows
67 * up at a later date, and as our interface with shmfs for memory allocation.
68 */
69
70/*
71 * We make up offsets for buffer objects so we can recognize them at
72 * mmap time.
73 */
74
75/* pgoff in mmap is an unsigned long, so we need to make sure that
76 * the faked up offset will fit
77 */
78
79#if BITS_PER_LONG == 64
80#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
81#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16)
82#else
83#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
84#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
85#endif
86
87/**
88 * drm_gem_init - Initialize the GEM device fields
89 * @dev: drm_devic structure to initialize
90 */
91int
92drm_gem_init(struct drm_device *dev)
93{
94 struct drm_vma_offset_manager *vma_offset_manager;
95
96 mutex_init(&dev->object_name_lock);
97 idr_init(&dev->object_name_idr);
98
99 vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL);
100 if (!vma_offset_manager) {
101 DRM_ERROR("out of memory\n");
102 return -ENOMEM;
103 }
104
105 dev->vma_offset_manager = vma_offset_manager;
106 drm_vma_offset_manager_init(vma_offset_manager,
107 DRM_FILE_PAGE_OFFSET_START,
108 DRM_FILE_PAGE_OFFSET_SIZE);
109
110 return 0;
111}
112
113void
114drm_gem_destroy(struct drm_device *dev)
115{
116
117 drm_vma_offset_manager_destroy(dev->vma_offset_manager);
118 kfree(dev->vma_offset_manager);
119 dev->vma_offset_manager = NULL;
120}
121
122/**
123 * drm_gem_object_init - initialize an allocated shmem-backed GEM object
124 * @dev: drm_device the object should be initialized for
125 * @obj: drm_gem_object to initialize
126 * @size: object size
127 *
128 * Initialize an already allocated GEM object of the specified size with
129 * shmfs backing store.
130 */
131int drm_gem_object_init(struct drm_device *dev,
132 struct drm_gem_object *obj, size_t size)
133{
134 struct file *filp;
135
136 drm_gem_private_object_init(dev, obj, size);
137
138 filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
139 if (IS_ERR(filp))
140 return PTR_ERR(filp);
141
142 obj->filp = filp;
143
144 return 0;
145}
146EXPORT_SYMBOL(drm_gem_object_init);
147
148/**
149 * drm_gem_object_init - initialize an allocated private GEM object
150 * @dev: drm_device the object should be initialized for
151 * @obj: drm_gem_object to initialize
152 * @size: object size
153 *
154 * Initialize an already allocated GEM object of the specified size with
155 * no GEM provided backing store. Instead the caller is responsible for
156 * backing the object and handling it.
157 */
158void drm_gem_private_object_init(struct drm_device *dev,
159 struct drm_gem_object *obj, size_t size)
160{
161 BUG_ON((size & (PAGE_SIZE - 1)) != 0);
162
163 obj->dev = dev;
164 obj->filp = NULL;
165
166 kref_init(&obj->refcount);
167 obj->handle_count = 0;
168 obj->size = size;
169 drm_vma_node_reset(&obj->vma_node);
170}
171EXPORT_SYMBOL(drm_gem_private_object_init);
172
173static void
174drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp)
175{
176 /*
177 * Note: obj->dma_buf can't disappear as long as we still hold a
178 * handle reference in obj->handle_count.
179 */
180 mutex_lock(&filp->prime.lock);
181 if (obj->dma_buf) {
182 drm_prime_remove_buf_handle_locked(&filp->prime,
183 obj->dma_buf);
184 }
185 mutex_unlock(&filp->prime.lock);
186}
187
188/**
189 * drm_gem_object_free - release resources bound to userspace handles
190 * @obj: GEM object to clean up.
191 *
192 * Called after the last handle to the object has been closed
193 *
194 * Removes any name for the object. Note that this must be
195 * called before drm_gem_object_free or we'll be touching
196 * freed memory
197 */
198static void drm_gem_object_handle_free(struct drm_gem_object *obj)
199{
200 struct drm_device *dev = obj->dev;
201
202 /* Remove any name for this object */
203 if (obj->name) {
204 idr_remove(&dev->object_name_idr, obj->name);
205 obj->name = 0;
206 }
207}
208
209static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj)
210{
211 /* Unbreak the reference cycle if we have an exported dma_buf. */
212 if (obj->dma_buf) {
213 dma_buf_put(obj->dma_buf);
214 obj->dma_buf = NULL;
215 }
216}
217
218static void
219drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj)
220{
221 if (WARN_ON(obj->handle_count == 0))
222 return;
223
224 /*
225 * Must bump handle count first as this may be the last
226 * ref, in which case the object would disappear before we
227 * checked for a name
228 */
229
230 mutex_lock(&obj->dev->object_name_lock);
231 if (--obj->handle_count == 0) {
232 drm_gem_object_handle_free(obj);
233 drm_gem_object_exported_dma_buf_free(obj);
234 }
235 mutex_unlock(&obj->dev->object_name_lock);
236
237 drm_gem_object_unreference_unlocked(obj);
238}
239
240/**
241 * drm_gem_handle_delete - deletes the given file-private handle
242 * @filp: drm file-private structure to use for the handle look up
243 * @handle: userspace handle to delete
244 *
245 * Removes the GEM handle from the @filp lookup table and if this is the last
246 * handle also cleans up linked resources like GEM names.
247 */
248int
249drm_gem_handle_delete(struct drm_file *filp, u32 handle)
250{
251 struct drm_device *dev;
252 struct drm_gem_object *obj;
253
254 /* This is gross. The idr system doesn't let us try a delete and
255 * return an error code. It just spews if you fail at deleting.
256 * So, we have to grab a lock around finding the object and then
257 * doing the delete on it and dropping the refcount, or the user
258 * could race us to double-decrement the refcount and cause a
259 * use-after-free later. Given the frequency of our handle lookups,
260 * we may want to use ida for number allocation and a hash table
261 * for the pointers, anyway.
262 */
263 spin_lock(&filp->table_lock);
264
265 /* Check if we currently have a reference on the object */
266 obj = idr_find(&filp->object_idr, handle);
267 if (obj == NULL) {
268 spin_unlock(&filp->table_lock);
269 return -EINVAL;
270 }
271 dev = obj->dev;
272
273 /* Release reference and decrement refcount. */
274 idr_remove(&filp->object_idr, handle);
275 spin_unlock(&filp->table_lock);
276
277 if (drm_core_check_feature(dev, DRIVER_PRIME))
278 drm_gem_remove_prime_handles(obj, filp);
279 drm_vma_node_revoke(&obj->vma_node, filp->filp);
280
281 if (dev->driver->gem_close_object)
282 dev->driver->gem_close_object(obj, filp);
283 drm_gem_object_handle_unreference_unlocked(obj);
284
285 return 0;
286}
287EXPORT_SYMBOL(drm_gem_handle_delete);
288
289/**
290 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers
291 * @file: drm file-private structure to remove the dumb handle from
292 * @dev: corresponding drm_device
293 * @handle: the dumb handle to remove
294 *
295 * This implements the ->dumb_destroy kms driver callback for drivers which use
296 * gem to manage their backing storage.
297 */
298int drm_gem_dumb_destroy(struct drm_file *file,
299 struct drm_device *dev,
300 uint32_t handle)
301{
302 return drm_gem_handle_delete(file, handle);
303}
304EXPORT_SYMBOL(drm_gem_dumb_destroy);
305
306/**
307 * drm_gem_handle_create_tail - internal functions to create a handle
308 * @file_priv: drm file-private structure to register the handle for
309 * @obj: object to register
310 * @handlep: pionter to return the created handle to the caller
311 *
312 * This expects the dev->object_name_lock to be held already and will drop it
313 * before returning. Used to avoid races in establishing new handles when
314 * importing an object from either an flink name or a dma-buf.
315 */
316int
317drm_gem_handle_create_tail(struct drm_file *file_priv,
318 struct drm_gem_object *obj,
319 u32 *handlep)
320{
321 struct drm_device *dev = obj->dev;
322 int ret;
323
324 WARN_ON(!mutex_is_locked(&dev->object_name_lock));
325
326 /*
327 * Get the user-visible handle using idr. Preload and perform
328 * allocation under our spinlock.
329 */
330 idr_preload(GFP_KERNEL);
331 spin_lock(&file_priv->table_lock);
332
333 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
334 drm_gem_object_reference(obj);
335 obj->handle_count++;
336 spin_unlock(&file_priv->table_lock);
337 idr_preload_end();
338 mutex_unlock(&dev->object_name_lock);
339 if (ret < 0) {
340 drm_gem_object_handle_unreference_unlocked(obj);
341 return ret;
342 }
343 *handlep = ret;
344
345 ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp);
346 if (ret) {
347 drm_gem_handle_delete(file_priv, *handlep);
348 return ret;
349 }
350
351 if (dev->driver->gem_open_object) {
352 ret = dev->driver->gem_open_object(obj, file_priv);
353 if (ret) {
354 drm_gem_handle_delete(file_priv, *handlep);
355 return ret;
356 }
357 }
358
359 return 0;
360}
361
362/**
363 * gem_handle_create - create a gem handle for an object
364 * @file_priv: drm file-private structure to register the handle for
365 * @obj: object to register
366 * @handlep: pionter to return the created handle to the caller
367 *
368 * Create a handle for this object. This adds a handle reference
369 * to the object, which includes a regular reference count. Callers
370 * will likely want to dereference the object afterwards.
371 */
372int
373drm_gem_handle_create(struct drm_file *file_priv,
374 struct drm_gem_object *obj,
375 u32 *handlep)
376{
377 mutex_lock(&obj->dev->object_name_lock);
378
379 return drm_gem_handle_create_tail(file_priv, obj, handlep);
380}
381EXPORT_SYMBOL(drm_gem_handle_create);
382
383
384/**
385 * drm_gem_free_mmap_offset - release a fake mmap offset for an object
386 * @obj: obj in question
387 *
388 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset().
389 */
390void
391drm_gem_free_mmap_offset(struct drm_gem_object *obj)
392{
393 struct drm_device *dev = obj->dev;
394
395 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node);
396}
397EXPORT_SYMBOL(drm_gem_free_mmap_offset);
398
399/**
400 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object
401 * @obj: obj in question
402 * @size: the virtual size
403 *
404 * GEM memory mapping works by handing back to userspace a fake mmap offset
405 * it can use in a subsequent mmap(2) call. The DRM core code then looks
406 * up the object based on the offset and sets up the various memory mapping
407 * structures.
408 *
409 * This routine allocates and attaches a fake offset for @obj, in cases where
410 * the virtual size differs from the physical size (ie. obj->size). Otherwise
411 * just use drm_gem_create_mmap_offset().
412 */
413int
414drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size)
415{
416 struct drm_device *dev = obj->dev;
417
418 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node,
419 size / PAGE_SIZE);
420}
421EXPORT_SYMBOL(drm_gem_create_mmap_offset_size);
422
423/**
424 * drm_gem_create_mmap_offset - create a fake mmap offset for an object
425 * @obj: obj in question
426 *
427 * GEM memory mapping works by handing back to userspace a fake mmap offset
428 * it can use in a subsequent mmap(2) call. The DRM core code then looks
429 * up the object based on the offset and sets up the various memory mapping
430 * structures.
431 *
432 * This routine allocates and attaches a fake offset for @obj.
433 */
434int drm_gem_create_mmap_offset(struct drm_gem_object *obj)
435{
436 return drm_gem_create_mmap_offset_size(obj, obj->size);
437}
438EXPORT_SYMBOL(drm_gem_create_mmap_offset);
439
440/**
441 * drm_gem_get_pages - helper to allocate backing pages for a GEM object
442 * from shmem
443 * @obj: obj in question
444 * @gfpmask: gfp mask of requested pages
445 */
446struct page **drm_gem_get_pages(struct drm_gem_object *obj, gfp_t gfpmask)
447{
448 struct inode *inode;
449 struct address_space *mapping;
450 struct page *p, **pages;
451 int i, npages;
452
453 /* This is the shared memory object that backs the GEM resource */
454 inode = file_inode(obj->filp);
455 mapping = inode->i_mapping;
456
457 /* We already BUG_ON() for non-page-aligned sizes in
458 * drm_gem_object_init(), so we should never hit this unless
459 * driver author is doing something really wrong:
460 */
461 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
462
463 npages = obj->size >> PAGE_SHIFT;
464
465 pages = drm_malloc_ab(npages, sizeof(struct page *));
466 if (pages == NULL)
467 return ERR_PTR(-ENOMEM);
468
469 gfpmask |= mapping_gfp_mask(mapping);
470
471 for (i = 0; i < npages; i++) {
472 p = shmem_read_mapping_page_gfp(mapping, i, gfpmask);
473 if (IS_ERR(p))
474 goto fail;
475 pages[i] = p;
476
477 /* There is a hypothetical issue w/ drivers that require
478 * buffer memory in the low 4GB.. if the pages are un-
479 * pinned, and swapped out, they can end up swapped back
480 * in above 4GB. If pages are already in memory, then
481 * shmem_read_mapping_page_gfp will ignore the gfpmask,
482 * even if the already in-memory page disobeys the mask.
483 *
484 * It is only a theoretical issue today, because none of
485 * the devices with this limitation can be populated with
486 * enough memory to trigger the issue. But this BUG_ON()
487 * is here as a reminder in case the problem with
488 * shmem_read_mapping_page_gfp() isn't solved by the time
489 * it does become a real issue.
490 *
491 * See this thread: http://lkml.org/lkml/2011/7/11/238
492 */
493 BUG_ON((gfpmask & __GFP_DMA32) &&
494 (page_to_pfn(p) >= 0x00100000UL));
495 }
496
497 return pages;
498
499fail:
500 while (i--)
501 page_cache_release(pages[i]);
502
503 drm_free_large(pages);
504 return ERR_CAST(p);
505}
506EXPORT_SYMBOL(drm_gem_get_pages);
507
508/**
509 * drm_gem_put_pages - helper to free backing pages for a GEM object
510 * @obj: obj in question
511 * @pages: pages to free
512 * @dirty: if true, pages will be marked as dirty
513 * @accessed: if true, the pages will be marked as accessed
514 */
515void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
516 bool dirty, bool accessed)
517{
518 int i, npages;
519
520 /* We already BUG_ON() for non-page-aligned sizes in
521 * drm_gem_object_init(), so we should never hit this unless
522 * driver author is doing something really wrong:
523 */
524 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
525
526 npages = obj->size >> PAGE_SHIFT;
527
528 for (i = 0; i < npages; i++) {
529 if (dirty)
530 set_page_dirty(pages[i]);
531
532 if (accessed)
533 mark_page_accessed(pages[i]);
534
535 /* Undo the reference we took when populating the table */
536 page_cache_release(pages[i]);
537 }
538
539 drm_free_large(pages);
540}
541EXPORT_SYMBOL(drm_gem_put_pages);
542
543/** Returns a reference to the object named by the handle. */
544struct drm_gem_object *
545drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp,
546 u32 handle)
547{
548 struct drm_gem_object *obj;
549
550 spin_lock(&filp->table_lock);
551
552 /* Check if we currently have a reference on the object */
553 obj = idr_find(&filp->object_idr, handle);
554 if (obj == NULL) {
555 spin_unlock(&filp->table_lock);
556 return NULL;
557 }
558
559 drm_gem_object_reference(obj);
560
561 spin_unlock(&filp->table_lock);
562
563 return obj;
564}
565EXPORT_SYMBOL(drm_gem_object_lookup);
566
567/**
568 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
569 * @dev: drm_device
570 * @data: ioctl data
571 * @file_priv: drm file-private structure
572 *
573 * Releases the handle to an mm object.
574 */
575int
576drm_gem_close_ioctl(struct drm_device *dev, void *data,
577 struct drm_file *file_priv)
578{
579 struct drm_gem_close *args = data;
580 int ret;
581
582 if (!(dev->driver->driver_features & DRIVER_GEM))
583 return -ENODEV;
584
585 ret = drm_gem_handle_delete(file_priv, args->handle);
586
587 return ret;
588}
589
590/**
591 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
592 * @dev: drm_device
593 * @data: ioctl data
594 * @file_priv: drm file-private structure
595 *
596 * Create a global name for an object, returning the name.
597 *
598 * Note that the name does not hold a reference; when the object
599 * is freed, the name goes away.
600 */
601int
602drm_gem_flink_ioctl(struct drm_device *dev, void *data,
603 struct drm_file *file_priv)
604{
605 struct drm_gem_flink *args = data;
606 struct drm_gem_object *obj;
607 int ret;
608
609 if (!(dev->driver->driver_features & DRIVER_GEM))
610 return -ENODEV;
611
612 obj = drm_gem_object_lookup(dev, file_priv, args->handle);
613 if (obj == NULL)
614 return -ENOENT;
615
616 mutex_lock(&dev->object_name_lock);
617 idr_preload(GFP_KERNEL);
618 /* prevent races with concurrent gem_close. */
619 if (obj->handle_count == 0) {
620 ret = -ENOENT;
621 goto err;
622 }
623
624 if (!obj->name) {
625 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT);
626 if (ret < 0)
627 goto err;
628
629 obj->name = ret;
630 }
631
632 args->name = (uint64_t) obj->name;
633 ret = 0;
634
635err:
636 idr_preload_end();
637 mutex_unlock(&dev->object_name_lock);
638 drm_gem_object_unreference_unlocked(obj);
639 return ret;
640}
641
642/**
643 * drm_gem_open - implementation of the GEM_OPEN ioctl
644 * @dev: drm_device
645 * @data: ioctl data
646 * @file_priv: drm file-private structure
647 *
648 * Open an object using the global name, returning a handle and the size.
649 *
650 * This handle (of course) holds a reference to the object, so the object
651 * will not go away until the handle is deleted.
652 */
653int
654drm_gem_open_ioctl(struct drm_device *dev, void *data,
655 struct drm_file *file_priv)
656{
657 struct drm_gem_open *args = data;
658 struct drm_gem_object *obj;
659 int ret;
660 u32 handle;
661
662 if (!(dev->driver->driver_features & DRIVER_GEM))
663 return -ENODEV;
664
665 mutex_lock(&dev->object_name_lock);
666 obj = idr_find(&dev->object_name_idr, (int) args->name);
667 if (obj) {
668 drm_gem_object_reference(obj);
669 } else {
670 mutex_unlock(&dev->object_name_lock);
671 return -ENOENT;
672 }
673
674 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */
675 ret = drm_gem_handle_create_tail(file_priv, obj, &handle);
676 drm_gem_object_unreference_unlocked(obj);
677 if (ret)
678 return ret;
679
680 args->handle = handle;
681 args->size = obj->size;
682
683 return 0;
684}
685
686/**
687 * gem_gem_open - initalizes GEM file-private structures at devnode open time
688 * @dev: drm_device which is being opened by userspace
689 * @file_private: drm file-private structure to set up
690 *
691 * Called at device open time, sets up the structure for handling refcounting
692 * of mm objects.
693 */
694void
695drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
696{
697 idr_init(&file_private->object_idr);
698 spin_lock_init(&file_private->table_lock);
699}
700
701/*
702 * Called at device close to release the file's
703 * handle references on objects.
704 */
705static int
706drm_gem_object_release_handle(int id, void *ptr, void *data)
707{
708 struct drm_file *file_priv = data;
709 struct drm_gem_object *obj = ptr;
710 struct drm_device *dev = obj->dev;
711
712 if (drm_core_check_feature(dev, DRIVER_PRIME))
713 drm_gem_remove_prime_handles(obj, file_priv);
714 drm_vma_node_revoke(&obj->vma_node, file_priv->filp);
715
716 if (dev->driver->gem_close_object)
717 dev->driver->gem_close_object(obj, file_priv);
718
719 drm_gem_object_handle_unreference_unlocked(obj);
720
721 return 0;
722}
723
724/**
725 * drm_gem_release - release file-private GEM resources
726 * @dev: drm_device which is being closed by userspace
727 * @file_private: drm file-private structure to clean up
728 *
729 * Called at close time when the filp is going away.
730 *
731 * Releases any remaining references on objects by this filp.
732 */
733void
734drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
735{
736 idr_for_each(&file_private->object_idr,
737 &drm_gem_object_release_handle, file_private);
738 idr_destroy(&file_private->object_idr);
739}
740
741void
742drm_gem_object_release(struct drm_gem_object *obj)
743{
744 WARN_ON(obj->dma_buf);
745
746 if (obj->filp)
747 fput(obj->filp);
748
749 drm_gem_free_mmap_offset(obj);
750}
751EXPORT_SYMBOL(drm_gem_object_release);
752
753/**
754 * drm_gem_object_free - free a GEM object
755 * @kref: kref of the object to free
756 *
757 * Called after the last reference to the object has been lost.
758 * Must be called holding struct_ mutex
759 *
760 * Frees the object
761 */
762void
763drm_gem_object_free(struct kref *kref)
764{
765 struct drm_gem_object *obj = (struct drm_gem_object *) kref;
766 struct drm_device *dev = obj->dev;
767
768 BUG_ON(!mutex_is_locked(&dev->struct_mutex));
769
770 if (dev->driver->gem_free_object != NULL)
771 dev->driver->gem_free_object(obj);
772}
773EXPORT_SYMBOL(drm_gem_object_free);
774
775void drm_gem_vm_open(struct vm_area_struct *vma)
776{
777 struct drm_gem_object *obj = vma->vm_private_data;
778
779 drm_gem_object_reference(obj);
780
781 mutex_lock(&obj->dev->struct_mutex);
782 drm_vm_open_locked(obj->dev, vma);
783 mutex_unlock(&obj->dev->struct_mutex);
784}
785EXPORT_SYMBOL(drm_gem_vm_open);
786
787void drm_gem_vm_close(struct vm_area_struct *vma)
788{
789 struct drm_gem_object *obj = vma->vm_private_data;
790 struct drm_device *dev = obj->dev;
791
792 mutex_lock(&dev->struct_mutex);
793 drm_vm_close_locked(obj->dev, vma);
794 drm_gem_object_unreference(obj);
795 mutex_unlock(&dev->struct_mutex);
796}
797EXPORT_SYMBOL(drm_gem_vm_close);
798
799/**
800 * drm_gem_mmap_obj - memory map a GEM object
801 * @obj: the GEM object to map
802 * @obj_size: the object size to be mapped, in bytes
803 * @vma: VMA for the area to be mapped
804 *
805 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops
806 * provided by the driver. Depending on their requirements, drivers can either
807 * provide a fault handler in their gem_vm_ops (in which case any accesses to
808 * the object will be trapped, to perform migration, GTT binding, surface
809 * register allocation, or performance monitoring), or mmap the buffer memory
810 * synchronously after calling drm_gem_mmap_obj.
811 *
812 * This function is mainly intended to implement the DMABUF mmap operation, when
813 * the GEM object is not looked up based on its fake offset. To implement the
814 * DRM mmap operation, drivers should use the drm_gem_mmap() function.
815 *
816 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while
817 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So
818 * callers must verify access restrictions before calling this helper.
819 *
820 * NOTE: This function has to be protected with dev->struct_mutex
821 *
822 * Return 0 or success or -EINVAL if the object size is smaller than the VMA
823 * size, or if no gem_vm_ops are provided.
824 */
825int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
826 struct vm_area_struct *vma)
827{
828 struct drm_device *dev = obj->dev;
829
830 lockdep_assert_held(&dev->struct_mutex);
831
832 /* Check for valid size. */
833 if (obj_size < vma->vm_end - vma->vm_start)
834 return -EINVAL;
835
836 if (!dev->driver->gem_vm_ops)
837 return -EINVAL;
838
839 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
840 vma->vm_ops = dev->driver->gem_vm_ops;
841 vma->vm_private_data = obj;
842 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
843
844 /* Take a ref for this mapping of the object, so that the fault
845 * handler can dereference the mmap offset's pointer to the object.
846 * This reference is cleaned up by the corresponding vm_close
847 * (which should happen whether the vma was created by this call, or
848 * by a vm_open due to mremap or partial unmap or whatever).
849 */
850 drm_gem_object_reference(obj);
851
852 drm_vm_open_locked(dev, vma);
853 return 0;
854}
855EXPORT_SYMBOL(drm_gem_mmap_obj);
856
857/**
858 * drm_gem_mmap - memory map routine for GEM objects
859 * @filp: DRM file pointer
860 * @vma: VMA for the area to be mapped
861 *
862 * If a driver supports GEM object mapping, mmap calls on the DRM file
863 * descriptor will end up here.
864 *
865 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will
866 * contain the fake offset we created when the GTT map ioctl was called on
867 * the object) and map it with a call to drm_gem_mmap_obj().
868 *
869 * If the caller is not granted access to the buffer object, the mmap will fail
870 * with EACCES. Please see the vma manager for more information.
871 */
872int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
873{
874 struct drm_file *priv = filp->private_data;
875 struct drm_device *dev = priv->minor->dev;
876 struct drm_gem_object *obj;
877 struct drm_vma_offset_node *node;
878 int ret;
879
880 if (drm_device_is_unplugged(dev))
881 return -ENODEV;
882
883 mutex_lock(&dev->struct_mutex);
884
885 node = drm_vma_offset_exact_lookup(dev->vma_offset_manager,
886 vma->vm_pgoff,
887 vma_pages(vma));
888 if (!node) {
889 mutex_unlock(&dev->struct_mutex);
890 return drm_mmap(filp, vma);
891 } else if (!drm_vma_node_is_allowed(node, filp)) {
892 mutex_unlock(&dev->struct_mutex);
893 return -EACCES;
894 }
895
896 obj = container_of(node, struct drm_gem_object, vma_node);
897 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT, vma);
898
899 mutex_unlock(&dev->struct_mutex);
900
901 return ret;
902}
903EXPORT_SYMBOL(drm_gem_mmap);