]> bbs.cooldavid.org Git - net-next-2.6.git/blame - drivers/gpu/drm/drm_gem.c
Merge branch 'pdc-regression' into release
[net-next-2.6.git] / drivers / gpu / drm / drm_gem.c
CommitLineData
673a394b
EA
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 "drmP.h"
38
39/** @file drm_gem.c
40 *
41 * This file provides some of the base ioctls and library routines for
42 * the graphics memory manager implemented by each device driver.
43 *
44 * Because various devices have different requirements in terms of
45 * synchronization and migration strategies, implementing that is left up to
46 * the driver, and all that the general API provides should be generic --
47 * allocating objects, reading/writing data with the cpu, freeing objects.
48 * Even there, platform-dependent optimizations for reading/writing data with
49 * the CPU mean we'll likely hook those out to driver-specific calls. However,
50 * the DRI2 implementation wants to have at least allocate/mmap be generic.
51 *
52 * The goal was to have swap-backed object allocation managed through
53 * struct file. However, file descriptors as handles to a struct file have
54 * two major failings:
55 * - Process limits prevent more than 1024 or so being used at a time by
56 * default.
57 * - Inability to allocate high fds will aggravate the X Server's select()
58 * handling, and likely that of many GL client applications as well.
59 *
60 * This led to a plan of using our own integer IDs (called handles, following
61 * DRM terminology) to mimic fds, and implement the fd syscalls we need as
62 * ioctls. The objects themselves will still include the struct file so
63 * that we can transition to fds if the required kernel infrastructure shows
64 * up at a later date, and as our interface with shmfs for memory allocation.
65 */
66
a2c0a97b
JB
67/*
68 * We make up offsets for buffer objects so we can recognize them at
69 * mmap time.
70 */
05269a3a
JC
71
72/* pgoff in mmap is an unsigned long, so we need to make sure that
73 * the faked up offset will fit
74 */
75
76#if BITS_PER_LONG == 64
a2c0a97b
JB
77#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
78#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16)
05269a3a
JC
79#else
80#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
81#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
82#endif
a2c0a97b 83
673a394b
EA
84/**
85 * Initialize the GEM device fields
86 */
87
88int
89drm_gem_init(struct drm_device *dev)
90{
a2c0a97b
JB
91 struct drm_gem_mm *mm;
92
673a394b
EA
93 spin_lock_init(&dev->object_name_lock);
94 idr_init(&dev->object_name_idr);
95 atomic_set(&dev->object_count, 0);
96 atomic_set(&dev->object_memory, 0);
97 atomic_set(&dev->pin_count, 0);
98 atomic_set(&dev->pin_memory, 0);
99 atomic_set(&dev->gtt_count, 0);
100 atomic_set(&dev->gtt_memory, 0);
a2c0a97b 101
9a298b2a 102 mm = kzalloc(sizeof(struct drm_gem_mm), GFP_KERNEL);
a2c0a97b
JB
103 if (!mm) {
104 DRM_ERROR("out of memory\n");
105 return -ENOMEM;
106 }
107
108 dev->mm_private = mm;
109
110 if (drm_ht_create(&mm->offset_hash, 19)) {
9a298b2a 111 kfree(mm);
a2c0a97b
JB
112 return -ENOMEM;
113 }
114
115 if (drm_mm_init(&mm->offset_manager, DRM_FILE_PAGE_OFFSET_START,
116 DRM_FILE_PAGE_OFFSET_SIZE)) {
a2c0a97b 117 drm_ht_remove(&mm->offset_hash);
9a298b2a 118 kfree(mm);
a2c0a97b
JB
119 return -ENOMEM;
120 }
121
673a394b
EA
122 return 0;
123}
124
a2c0a97b
JB
125void
126drm_gem_destroy(struct drm_device *dev)
127{
128 struct drm_gem_mm *mm = dev->mm_private;
129
130 drm_mm_takedown(&mm->offset_manager);
131 drm_ht_remove(&mm->offset_hash);
9a298b2a 132 kfree(mm);
a2c0a97b
JB
133 dev->mm_private = NULL;
134}
135
1d397043
DV
136/**
137 * Initialize an already allocate GEM object of the specified size with
138 * shmfs backing store.
139 */
140int drm_gem_object_init(struct drm_device *dev,
141 struct drm_gem_object *obj, size_t size)
142{
143 BUG_ON((size & (PAGE_SIZE - 1)) != 0);
144
145 obj->dev = dev;
146 obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
147 if (IS_ERR(obj->filp))
148 return -ENOMEM;
149
150 kref_init(&obj->refcount);
29d08b3e 151 atomic_set(&obj->handle_count, 0);
1d397043
DV
152 obj->size = size;
153
154 atomic_inc(&dev->object_count);
155 atomic_add(obj->size, &dev->object_memory);
156
157 return 0;
158}
159EXPORT_SYMBOL(drm_gem_object_init);
160
673a394b
EA
161/**
162 * Allocate a GEM object of the specified size with shmfs backing store
163 */
164struct drm_gem_object *
165drm_gem_object_alloc(struct drm_device *dev, size_t size)
166{
167 struct drm_gem_object *obj;
168
b798b1fe 169 obj = kzalloc(sizeof(*obj), GFP_KERNEL);
845792d9
JS
170 if (!obj)
171 goto free;
673a394b 172
1d397043 173 if (drm_gem_object_init(dev, obj, size) != 0)
845792d9 174 goto free;
673a394b 175
673a394b
EA
176 if (dev->driver->gem_init_object != NULL &&
177 dev->driver->gem_init_object(obj) != 0) {
845792d9 178 goto fput;
673a394b 179 }
673a394b 180 return obj;
845792d9 181fput:
1d397043
DV
182 /* Object_init mangles the global counters - readjust them. */
183 atomic_dec(&dev->object_count);
184 atomic_sub(obj->size, &dev->object_memory);
845792d9
JS
185 fput(obj->filp);
186free:
187 kfree(obj);
188 return NULL;
673a394b
EA
189}
190EXPORT_SYMBOL(drm_gem_object_alloc);
191
192/**
193 * Removes the mapping from handle to filp for this object.
194 */
195static int
a1a2d1d3 196drm_gem_handle_delete(struct drm_file *filp, u32 handle)
673a394b
EA
197{
198 struct drm_device *dev;
199 struct drm_gem_object *obj;
200
201 /* This is gross. The idr system doesn't let us try a delete and
202 * return an error code. It just spews if you fail at deleting.
203 * So, we have to grab a lock around finding the object and then
204 * doing the delete on it and dropping the refcount, or the user
205 * could race us to double-decrement the refcount and cause a
206 * use-after-free later. Given the frequency of our handle lookups,
207 * we may want to use ida for number allocation and a hash table
208 * for the pointers, anyway.
209 */
210 spin_lock(&filp->table_lock);
211
212 /* Check if we currently have a reference on the object */
213 obj = idr_find(&filp->object_idr, handle);
214 if (obj == NULL) {
215 spin_unlock(&filp->table_lock);
216 return -EINVAL;
217 }
218 dev = obj->dev;
219
220 /* Release reference and decrement refcount. */
221 idr_remove(&filp->object_idr, handle);
222 spin_unlock(&filp->table_lock);
223
bc9025bd 224 drm_gem_object_handle_unreference_unlocked(obj);
673a394b
EA
225
226 return 0;
227}
228
229/**
230 * Create a handle for this object. This adds a handle reference
231 * to the object, which includes a regular reference count. Callers
232 * will likely want to dereference the object afterwards.
233 */
234int
235drm_gem_handle_create(struct drm_file *file_priv,
236 struct drm_gem_object *obj,
a1a2d1d3 237 u32 *handlep)
673a394b
EA
238{
239 int ret;
240
241 /*
242 * Get the user-visible handle using idr.
243 */
244again:
245 /* ensure there is space available to allocate a handle */
246 if (idr_pre_get(&file_priv->object_idr, GFP_KERNEL) == 0)
247 return -ENOMEM;
248
249 /* do the allocation under our spinlock */
250 spin_lock(&file_priv->table_lock);
a1a2d1d3 251 ret = idr_get_new_above(&file_priv->object_idr, obj, 1, (int *)handlep);
673a394b
EA
252 spin_unlock(&file_priv->table_lock);
253 if (ret == -EAGAIN)
254 goto again;
255
256 if (ret != 0)
257 return ret;
258
259 drm_gem_object_handle_reference(obj);
260 return 0;
261}
262EXPORT_SYMBOL(drm_gem_handle_create);
263
264/** Returns a reference to the object named by the handle. */
265struct drm_gem_object *
266drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp,
a1a2d1d3 267 u32 handle)
673a394b
EA
268{
269 struct drm_gem_object *obj;
270
271 spin_lock(&filp->table_lock);
272
273 /* Check if we currently have a reference on the object */
274 obj = idr_find(&filp->object_idr, handle);
275 if (obj == NULL) {
276 spin_unlock(&filp->table_lock);
277 return NULL;
278 }
279
280 drm_gem_object_reference(obj);
281
282 spin_unlock(&filp->table_lock);
283
284 return obj;
285}
286EXPORT_SYMBOL(drm_gem_object_lookup);
287
288/**
289 * Releases the handle to an mm object.
290 */
291int
292drm_gem_close_ioctl(struct drm_device *dev, void *data,
293 struct drm_file *file_priv)
294{
295 struct drm_gem_close *args = data;
296 int ret;
297
298 if (!(dev->driver->driver_features & DRIVER_GEM))
299 return -ENODEV;
300
301 ret = drm_gem_handle_delete(file_priv, args->handle);
302
303 return ret;
304}
305
306/**
307 * Create a global name for an object, returning the name.
308 *
309 * Note that the name does not hold a reference; when the object
310 * is freed, the name goes away.
311 */
312int
313drm_gem_flink_ioctl(struct drm_device *dev, void *data,
314 struct drm_file *file_priv)
315{
316 struct drm_gem_flink *args = data;
317 struct drm_gem_object *obj;
318 int ret;
319
320 if (!(dev->driver->driver_features & DRIVER_GEM))
321 return -ENODEV;
322
323 obj = drm_gem_object_lookup(dev, file_priv, args->handle);
324 if (obj == NULL)
bf79cb91 325 return -ENOENT;
673a394b
EA
326
327again:
3e49c4f4
CW
328 if (idr_pre_get(&dev->object_name_idr, GFP_KERNEL) == 0) {
329 ret = -ENOMEM;
330 goto err;
331 }
673a394b
EA
332
333 spin_lock(&dev->object_name_lock);
8d59bae5
CW
334 if (!obj->name) {
335 ret = idr_get_new_above(&dev->object_name_idr, obj, 1,
336 &obj->name);
337 args->name = (uint64_t) obj->name;
673a394b 338 spin_unlock(&dev->object_name_lock);
673a394b 339
8d59bae5
CW
340 if (ret == -EAGAIN)
341 goto again;
673a394b 342
8d59bae5
CW
343 if (ret != 0)
344 goto err;
673a394b 345
8d59bae5
CW
346 /* Allocate a reference for the name table. */
347 drm_gem_object_reference(obj);
348 } else {
349 args->name = (uint64_t) obj->name;
350 spin_unlock(&dev->object_name_lock);
351 ret = 0;
352 }
3e49c4f4
CW
353
354err:
bc9025bd 355 drm_gem_object_unreference_unlocked(obj);
3e49c4f4 356 return ret;
673a394b
EA
357}
358
359/**
360 * Open an object using the global name, returning a handle and the size.
361 *
362 * This handle (of course) holds a reference to the object, so the object
363 * will not go away until the handle is deleted.
364 */
365int
366drm_gem_open_ioctl(struct drm_device *dev, void *data,
367 struct drm_file *file_priv)
368{
369 struct drm_gem_open *args = data;
370 struct drm_gem_object *obj;
371 int ret;
a1a2d1d3 372 u32 handle;
673a394b
EA
373
374 if (!(dev->driver->driver_features & DRIVER_GEM))
375 return -ENODEV;
376
377 spin_lock(&dev->object_name_lock);
378 obj = idr_find(&dev->object_name_idr, (int) args->name);
379 if (obj)
380 drm_gem_object_reference(obj);
381 spin_unlock(&dev->object_name_lock);
382 if (!obj)
383 return -ENOENT;
384
385 ret = drm_gem_handle_create(file_priv, obj, &handle);
bc9025bd 386 drm_gem_object_unreference_unlocked(obj);
673a394b
EA
387 if (ret)
388 return ret;
389
390 args->handle = handle;
391 args->size = obj->size;
392
393 return 0;
394}
395
396/**
397 * Called at device open time, sets up the structure for handling refcounting
398 * of mm objects.
399 */
400void
401drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
402{
403 idr_init(&file_private->object_idr);
404 spin_lock_init(&file_private->table_lock);
405}
406
407/**
408 * Called at device close to release the file's
409 * handle references on objects.
410 */
411static int
412drm_gem_object_release_handle(int id, void *ptr, void *data)
413{
414 struct drm_gem_object *obj = ptr;
415
bc9025bd 416 drm_gem_object_handle_unreference_unlocked(obj);
673a394b
EA
417
418 return 0;
419}
420
421/**
422 * Called at close time when the filp is going away.
423 *
424 * Releases any remaining references on objects by this filp.
425 */
426void
427drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
428{
673a394b
EA
429 idr_for_each(&file_private->object_idr,
430 &drm_gem_object_release_handle, NULL);
431
ddd3d069 432 idr_remove_all(&file_private->object_idr);
673a394b 433 idr_destroy(&file_private->object_idr);
673a394b
EA
434}
435
fd632aa3
DV
436void
437drm_gem_object_release(struct drm_gem_object *obj)
c3ae90c0
LB
438{
439 struct drm_device *dev = obj->dev;
440 fput(obj->filp);
441 atomic_dec(&dev->object_count);
442 atomic_sub(obj->size, &dev->object_memory);
c3ae90c0 443}
fd632aa3 444EXPORT_SYMBOL(drm_gem_object_release);
c3ae90c0 445
673a394b
EA
446/**
447 * Called after the last reference to the object has been lost.
c3ae90c0 448 * Must be called holding struct_ mutex
673a394b
EA
449 *
450 * Frees the object
451 */
452void
453drm_gem_object_free(struct kref *kref)
454{
455 struct drm_gem_object *obj = (struct drm_gem_object *) kref;
456 struct drm_device *dev = obj->dev;
457
458 BUG_ON(!mutex_is_locked(&dev->struct_mutex));
459
460 if (dev->driver->gem_free_object != NULL)
461 dev->driver->gem_free_object(obj);
673a394b
EA
462}
463EXPORT_SYMBOL(drm_gem_object_free);
464
c3ae90c0
LB
465static void drm_gem_object_ref_bug(struct kref *list_kref)
466{
467 BUG();
468}
469
673a394b
EA
470/**
471 * Called after the last handle to the object has been closed
472 *
473 * Removes any name for the object. Note that this must be
474 * called before drm_gem_object_free or we'll be touching
475 * freed memory
476 */
29d08b3e 477void drm_gem_object_handle_free(struct drm_gem_object *obj)
673a394b 478{
673a394b
EA
479 struct drm_device *dev = obj->dev;
480
481 /* Remove any name for this object */
482 spin_lock(&dev->object_name_lock);
483 if (obj->name) {
484 idr_remove(&dev->object_name_idr, obj->name);
8d59bae5 485 obj->name = 0;
673a394b
EA
486 spin_unlock(&dev->object_name_lock);
487 /*
488 * The object name held a reference to this object, drop
489 * that now.
c3ae90c0
LB
490 *
491 * This cannot be the last reference, since the handle holds one too.
673a394b 492 */
c3ae90c0 493 kref_put(&obj->refcount, drm_gem_object_ref_bug);
673a394b
EA
494 } else
495 spin_unlock(&dev->object_name_lock);
496
497}
498EXPORT_SYMBOL(drm_gem_object_handle_free);
499
ab00b3e5
JB
500void drm_gem_vm_open(struct vm_area_struct *vma)
501{
502 struct drm_gem_object *obj = vma->vm_private_data;
503
504 drm_gem_object_reference(obj);
31dfbc93
CW
505
506 mutex_lock(&obj->dev->struct_mutex);
507 drm_vm_open_locked(vma);
508 mutex_unlock(&obj->dev->struct_mutex);
ab00b3e5
JB
509}
510EXPORT_SYMBOL(drm_gem_vm_open);
511
512void drm_gem_vm_close(struct vm_area_struct *vma)
513{
514 struct drm_gem_object *obj = vma->vm_private_data;
ab00b3e5 515
31dfbc93
CW
516 mutex_lock(&obj->dev->struct_mutex);
517 drm_vm_close_locked(vma);
518 drm_gem_object_unreference(obj);
519 mutex_unlock(&obj->dev->struct_mutex);
ab00b3e5
JB
520}
521EXPORT_SYMBOL(drm_gem_vm_close);
522
523
a2c0a97b
JB
524/**
525 * drm_gem_mmap - memory map routine for GEM objects
526 * @filp: DRM file pointer
527 * @vma: VMA for the area to be mapped
528 *
529 * If a driver supports GEM object mapping, mmap calls on the DRM file
530 * descriptor will end up here.
531 *
532 * If we find the object based on the offset passed in (vma->vm_pgoff will
533 * contain the fake offset we created when the GTT map ioctl was called on
534 * the object), we set up the driver fault handler so that any accesses
535 * to the object can be trapped, to perform migration, GTT binding, surface
536 * register allocation, or performance monitoring.
537 */
538int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
539{
540 struct drm_file *priv = filp->private_data;
541 struct drm_device *dev = priv->minor->dev;
542 struct drm_gem_mm *mm = dev->mm_private;
f77d390c 543 struct drm_local_map *map = NULL;
a2c0a97b
JB
544 struct drm_gem_object *obj;
545 struct drm_hash_item *hash;
a2c0a97b
JB
546 int ret = 0;
547
548 mutex_lock(&dev->struct_mutex);
549
550 if (drm_ht_find_item(&mm->offset_hash, vma->vm_pgoff, &hash)) {
551 mutex_unlock(&dev->struct_mutex);
552 return drm_mmap(filp, vma);
553 }
554
555 map = drm_hash_entry(hash, struct drm_map_list, hash)->map;
556 if (!map ||
557 ((map->flags & _DRM_RESTRICTED) && !capable(CAP_SYS_ADMIN))) {
558 ret = -EPERM;
559 goto out_unlock;
560 }
561
562 /* Check for valid size. */
563 if (map->size < vma->vm_end - vma->vm_start) {
564 ret = -EINVAL;
565 goto out_unlock;
566 }
567
568 obj = map->handle;
569 if (!obj->dev->driver->gem_vm_ops) {
570 ret = -EINVAL;
571 goto out_unlock;
572 }
573
574 vma->vm_flags |= VM_RESERVED | VM_IO | VM_PFNMAP | VM_DONTEXPAND;
575 vma->vm_ops = obj->dev->driver->gem_vm_ops;
576 vma->vm_private_data = map->handle;
79cc304f 577 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
a2c0a97b 578
ab00b3e5
JB
579 /* Take a ref for this mapping of the object, so that the fault
580 * handler can dereference the mmap offset's pointer to the object.
581 * This reference is cleaned up by the corresponding vm_close
582 * (which should happen whether the vma was created by this call, or
583 * by a vm_open due to mremap or partial unmap or whatever).
584 */
585 drm_gem_object_reference(obj);
586
a2c0a97b
JB
587 vma->vm_file = filp; /* Needed for drm_vm_open() */
588 drm_vm_open_locked(vma);
589
590out_unlock:
591 mutex_unlock(&dev->struct_mutex);
592
593 return ret;
594}
595EXPORT_SYMBOL(drm_gem_mmap);