blob: ad955d7c99fd6417250c7df634030260c9f4f25c [file] [log] [blame]
Eric Anholt673a3942008-07-30 12:06:12 -07001/*
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>
Hugh Dickins5949eac2011-06-27 16:18:18 -070037#include <linux/shmem_fs.h>
Dave Airlie32488772011-11-25 15:21:02 +000038#include <linux/dma-buf.h>
David Howells760285e2012-10-02 18:01:07 +010039#include <drm/drmP.h>
David Herrmann0de23972013-07-24 21:07:52 +020040#include <drm/drm_vma_manager.h>
Daniel Vetterd9fc9412014-09-23 15:46:53 +020041#include <drm/drm_gem.h>
Daniel Vetter67d0ec42014-09-10 12:43:53 +020042#include "drm_internal.h"
Eric Anholt673a3942008-07-30 12:06:12 -070043
44/** @file drm_gem.c
45 *
46 * This file provides some of the base ioctls and library routines for
47 * the graphics memory manager implemented by each device driver.
48 *
49 * Because various devices have different requirements in terms of
50 * synchronization and migration strategies, implementing that is left up to
51 * the driver, and all that the general API provides should be generic --
52 * allocating objects, reading/writing data with the cpu, freeing objects.
53 * Even there, platform-dependent optimizations for reading/writing data with
54 * the CPU mean we'll likely hook those out to driver-specific calls. However,
55 * the DRI2 implementation wants to have at least allocate/mmap be generic.
56 *
57 * The goal was to have swap-backed object allocation managed through
58 * struct file. However, file descriptors as handles to a struct file have
59 * two major failings:
60 * - Process limits prevent more than 1024 or so being used at a time by
61 * default.
62 * - Inability to allocate high fds will aggravate the X Server's select()
63 * handling, and likely that of many GL client applications as well.
64 *
65 * This led to a plan of using our own integer IDs (called handles, following
66 * DRM terminology) to mimic fds, and implement the fd syscalls we need as
67 * ioctls. The objects themselves will still include the struct file so
68 * that we can transition to fds if the required kernel infrastructure shows
69 * up at a later date, and as our interface with shmfs for memory allocation.
70 */
71
Jesse Barnesa2c0a972008-11-05 10:31:53 -080072/*
73 * We make up offsets for buffer objects so we can recognize them at
74 * mmap time.
75 */
Jordan Crouse05269a32010-05-27 13:40:27 -060076
77/* pgoff in mmap is an unsigned long, so we need to make sure that
78 * the faked up offset will fit
79 */
80
81#if BITS_PER_LONG == 64
Jesse Barnesa2c0a972008-11-05 10:31:53 -080082#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFFUL >> PAGE_SHIFT) + 1)
83#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFFUL >> PAGE_SHIFT) * 16)
Jordan Crouse05269a32010-05-27 13:40:27 -060084#else
85#define DRM_FILE_PAGE_OFFSET_START ((0xFFFFFFFUL >> PAGE_SHIFT) + 1)
86#define DRM_FILE_PAGE_OFFSET_SIZE ((0xFFFFFFFUL >> PAGE_SHIFT) * 16)
87#endif
Jesse Barnesa2c0a972008-11-05 10:31:53 -080088
Eric Anholt673a3942008-07-30 12:06:12 -070089/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +010090 * drm_gem_init - Initialize the GEM device fields
91 * @dev: drm_devic structure to initialize
Eric Anholt673a3942008-07-30 12:06:12 -070092 */
Eric Anholt673a3942008-07-30 12:06:12 -070093int
94drm_gem_init(struct drm_device *dev)
95{
Daniel Vetterb04a5902013-12-11 14:24:46 +010096 struct drm_vma_offset_manager *vma_offset_manager;
Jesse Barnesa2c0a972008-11-05 10:31:53 -080097
Daniel Vettercd4f0132013-08-15 00:02:44 +020098 mutex_init(&dev->object_name_lock);
Eric Anholt673a3942008-07-30 12:06:12 -070099 idr_init(&dev->object_name_idr);
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800100
Daniel Vetterb04a5902013-12-11 14:24:46 +0100101 vma_offset_manager = kzalloc(sizeof(*vma_offset_manager), GFP_KERNEL);
102 if (!vma_offset_manager) {
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800103 DRM_ERROR("out of memory\n");
104 return -ENOMEM;
105 }
106
Daniel Vetterb04a5902013-12-11 14:24:46 +0100107 dev->vma_offset_manager = vma_offset_manager;
108 drm_vma_offset_manager_init(vma_offset_manager,
David Herrmann0de23972013-07-24 21:07:52 +0200109 DRM_FILE_PAGE_OFFSET_START,
110 DRM_FILE_PAGE_OFFSET_SIZE);
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800111
Eric Anholt673a3942008-07-30 12:06:12 -0700112 return 0;
113}
114
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800115void
116drm_gem_destroy(struct drm_device *dev)
117{
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800118
Daniel Vetterb04a5902013-12-11 14:24:46 +0100119 drm_vma_offset_manager_destroy(dev->vma_offset_manager);
120 kfree(dev->vma_offset_manager);
121 dev->vma_offset_manager = NULL;
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800122}
123
Eric Anholt673a3942008-07-30 12:06:12 -0700124/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100125 * drm_gem_object_init - initialize an allocated shmem-backed GEM object
126 * @dev: drm_device the object should be initialized for
127 * @obj: drm_gem_object to initialize
128 * @size: object size
129 *
Alan Cox62cb70112011-06-07 14:17:51 +0100130 * Initialize an already allocated GEM object of the specified size with
Daniel Vetter1d397042010-04-09 19:05:04 +0000131 * shmfs backing store.
132 */
133int drm_gem_object_init(struct drm_device *dev,
134 struct drm_gem_object *obj, size_t size)
135{
David Herrmann89c82332013-07-11 11:56:32 +0200136 struct file *filp;
Daniel Vetter1d397042010-04-09 19:05:04 +0000137
Daniel Vetter6ab11a22014-01-20 08:21:54 +0100138 drm_gem_private_object_init(dev, obj, size);
139
David Herrmann89c82332013-07-11 11:56:32 +0200140 filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
141 if (IS_ERR(filp))
142 return PTR_ERR(filp);
Daniel Vetter1d397042010-04-09 19:05:04 +0000143
David Herrmann89c82332013-07-11 11:56:32 +0200144 obj->filp = filp;
Daniel Vetter1d397042010-04-09 19:05:04 +0000145
Daniel Vetter1d397042010-04-09 19:05:04 +0000146 return 0;
147}
148EXPORT_SYMBOL(drm_gem_object_init);
149
150/**
Laurent Pinchart2a5706a2014-08-28 14:34:36 +0200151 * drm_gem_private_object_init - initialize an allocated private GEM object
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100152 * @dev: drm_device the object should be initialized for
153 * @obj: drm_gem_object to initialize
154 * @size: object size
155 *
Alan Cox62cb70112011-06-07 14:17:51 +0100156 * Initialize an already allocated GEM object of the specified size with
157 * no GEM provided backing store. Instead the caller is responsible for
158 * backing the object and handling it.
159 */
David Herrmann89c82332013-07-11 11:56:32 +0200160void drm_gem_private_object_init(struct drm_device *dev,
161 struct drm_gem_object *obj, size_t size)
Alan Cox62cb70112011-06-07 14:17:51 +0100162{
163 BUG_ON((size & (PAGE_SIZE - 1)) != 0);
164
165 obj->dev = dev;
166 obj->filp = NULL;
167
168 kref_init(&obj->refcount);
Daniel Vettera8e11d12013-08-15 00:02:37 +0200169 obj->handle_count = 0;
Alan Cox62cb70112011-06-07 14:17:51 +0100170 obj->size = size;
David Herrmann88d7ebe2013-08-25 18:28:57 +0200171 drm_vma_node_reset(&obj->vma_node);
Alan Cox62cb70112011-06-07 14:17:51 +0100172}
173EXPORT_SYMBOL(drm_gem_private_object_init);
174
Dave Airlie0ff926c2012-05-20 17:31:16 +0100175static void
176drm_gem_remove_prime_handles(struct drm_gem_object *obj, struct drm_file *filp)
177{
Daniel Vetter319c9332013-08-15 00:02:46 +0200178 /*
179 * Note: obj->dma_buf can't disappear as long as we still hold a
180 * handle reference in obj->handle_count.
181 */
Daniel Vetterd0b2c532013-08-15 00:02:49 +0200182 mutex_lock(&filp->prime.lock);
Daniel Vetter319c9332013-08-15 00:02:46 +0200183 if (obj->dma_buf) {
Daniel Vetterd0b2c532013-08-15 00:02:49 +0200184 drm_prime_remove_buf_handle_locked(&filp->prime,
185 obj->dma_buf);
Dave Airlie0ff926c2012-05-20 17:31:16 +0100186 }
Daniel Vetterd0b2c532013-08-15 00:02:49 +0200187 mutex_unlock(&filp->prime.lock);
Dave Airlie0ff926c2012-05-20 17:31:16 +0100188}
189
Daniel Vetter36da5902013-08-15 00:02:34 +0200190/**
Thierry Redingc6a84322014-10-02 14:45:55 +0200191 * drm_gem_object_handle_free - release resources bound to userspace handles
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100192 * @obj: GEM object to clean up.
193 *
Daniel Vetter36da5902013-08-15 00:02:34 +0200194 * Called after the last handle to the object has been closed
195 *
196 * Removes any name for the object. Note that this must be
197 * called before drm_gem_object_free or we'll be touching
198 * freed memory
199 */
200static void drm_gem_object_handle_free(struct drm_gem_object *obj)
201{
202 struct drm_device *dev = obj->dev;
203
204 /* Remove any name for this object */
Daniel Vetter36da5902013-08-15 00:02:34 +0200205 if (obj->name) {
206 idr_remove(&dev->object_name_idr, obj->name);
207 obj->name = 0;
Daniel Vettera8e11d12013-08-15 00:02:37 +0200208 }
Daniel Vetter36da5902013-08-15 00:02:34 +0200209}
210
Daniel Vetter319c9332013-08-15 00:02:46 +0200211static void drm_gem_object_exported_dma_buf_free(struct drm_gem_object *obj)
212{
213 /* Unbreak the reference cycle if we have an exported dma_buf. */
214 if (obj->dma_buf) {
215 dma_buf_put(obj->dma_buf);
216 obj->dma_buf = NULL;
217 }
218}
219
Daniel Vetterbecee2a2013-08-15 00:02:39 +0200220static void
Daniel Vetter36da5902013-08-15 00:02:34 +0200221drm_gem_object_handle_unreference_unlocked(struct drm_gem_object *obj)
222{
Chris Wilson98a88832016-01-04 10:11:00 +0000223 struct drm_device *dev = obj->dev;
224 bool final = false;
225
Daniel Vettera8e11d12013-08-15 00:02:37 +0200226 if (WARN_ON(obj->handle_count == 0))
Daniel Vetter36da5902013-08-15 00:02:34 +0200227 return;
228
229 /*
230 * Must bump handle count first as this may be the last
231 * ref, in which case the object would disappear before we
232 * checked for a name
233 */
234
Chris Wilson98a88832016-01-04 10:11:00 +0000235 mutex_lock(&dev->object_name_lock);
Daniel Vetter319c9332013-08-15 00:02:46 +0200236 if (--obj->handle_count == 0) {
Daniel Vetter36da5902013-08-15 00:02:34 +0200237 drm_gem_object_handle_free(obj);
Daniel Vetter319c9332013-08-15 00:02:46 +0200238 drm_gem_object_exported_dma_buf_free(obj);
Chris Wilson98a88832016-01-04 10:11:00 +0000239 final = true;
Daniel Vetter319c9332013-08-15 00:02:46 +0200240 }
Chris Wilson98a88832016-01-04 10:11:00 +0000241 mutex_unlock(&dev->object_name_lock);
Daniel Vettera8e11d12013-08-15 00:02:37 +0200242
Chris Wilson98a88832016-01-04 10:11:00 +0000243 if (final)
244 drm_gem_object_unreference_unlocked(obj);
Daniel Vetter36da5902013-08-15 00:02:34 +0200245}
246
Eric Anholt673a3942008-07-30 12:06:12 -0700247/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100248 * drm_gem_handle_delete - deletes the given file-private handle
249 * @filp: drm file-private structure to use for the handle look up
250 * @handle: userspace handle to delete
251 *
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200252 * Removes the GEM handle from the @filp lookup table which has been added with
253 * drm_gem_handle_create(). If this is the last handle also cleans up linked
254 * resources like GEM names.
Eric Anholt673a3942008-07-30 12:06:12 -0700255 */
Dave Airlieff72145b2011-02-07 12:16:14 +1000256int
Pekka Paalanena1a2d1d2009-08-23 12:40:55 +0300257drm_gem_handle_delete(struct drm_file *filp, u32 handle)
Eric Anholt673a3942008-07-30 12:06:12 -0700258{
259 struct drm_device *dev;
260 struct drm_gem_object *obj;
261
262 /* This is gross. The idr system doesn't let us try a delete and
263 * return an error code. It just spews if you fail at deleting.
264 * So, we have to grab a lock around finding the object and then
265 * doing the delete on it and dropping the refcount, or the user
266 * could race us to double-decrement the refcount and cause a
267 * use-after-free later. Given the frequency of our handle lookups,
268 * we may want to use ida for number allocation and a hash table
269 * for the pointers, anyway.
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 -EINVAL;
278 }
279 dev = obj->dev;
280
281 /* Release reference and decrement refcount. */
282 idr_remove(&filp->object_idr, handle);
283 spin_unlock(&filp->table_lock);
284
Thierry Reding9c784852013-08-28 12:04:14 +0200285 if (drm_core_check_feature(dev, DRIVER_PRIME))
286 drm_gem_remove_prime_handles(obj, filp);
David Herrmannca481c92013-08-25 18:28:58 +0200287 drm_vma_node_revoke(&obj->vma_node, filp->filp);
Dave Airlie32488772011-11-25 15:21:02 +0000288
Ben Skeggs304eda32011-06-09 00:24:59 +0000289 if (dev->driver->gem_close_object)
290 dev->driver->gem_close_object(obj, filp);
Luca Barbieribc9025b2010-02-09 05:49:12 +0000291 drm_gem_object_handle_unreference_unlocked(obj);
Eric Anholt673a3942008-07-30 12:06:12 -0700292
293 return 0;
294}
Dave Airlieff72145b2011-02-07 12:16:14 +1000295EXPORT_SYMBOL(drm_gem_handle_delete);
Eric Anholt673a3942008-07-30 12:06:12 -0700296
297/**
Daniel Vetter43387b32013-07-16 09:12:04 +0200298 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100299 * @file: drm file-private structure to remove the dumb handle from
300 * @dev: corresponding drm_device
301 * @handle: the dumb handle to remove
Daniel Vetter43387b32013-07-16 09:12:04 +0200302 *
303 * This implements the ->dumb_destroy kms driver callback for drivers which use
304 * gem to manage their backing storage.
305 */
306int drm_gem_dumb_destroy(struct drm_file *file,
307 struct drm_device *dev,
308 uint32_t handle)
309{
310 return drm_gem_handle_delete(file, handle);
311}
312EXPORT_SYMBOL(drm_gem_dumb_destroy);
313
314/**
Daniel Vetter20228c42013-08-15 00:02:45 +0200315 * drm_gem_handle_create_tail - internal functions to create a handle
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100316 * @file_priv: drm file-private structure to register the handle for
317 * @obj: object to register
Thierry Reding8bf81802014-11-03 13:20:52 +0100318 * @handlep: pointer to return the created handle to the caller
Daniel Vetter20228c42013-08-15 00:02:45 +0200319 *
320 * This expects the dev->object_name_lock to be held already and will drop it
321 * before returning. Used to avoid races in establishing new handles when
322 * importing an object from either an flink name or a dma-buf.
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200323 *
324 * Handles must be release again through drm_gem_handle_delete(). This is done
325 * when userspace closes @file_priv for all attached handles, or through the
326 * GEM_CLOSE ioctl for individual handles.
Eric Anholt673a3942008-07-30 12:06:12 -0700327 */
328int
Daniel Vetter20228c42013-08-15 00:02:45 +0200329drm_gem_handle_create_tail(struct drm_file *file_priv,
330 struct drm_gem_object *obj,
331 u32 *handlep)
Eric Anholt673a3942008-07-30 12:06:12 -0700332{
Ben Skeggs304eda32011-06-09 00:24:59 +0000333 struct drm_device *dev = obj->dev;
334 int ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700335
Daniel Vetter20228c42013-08-15 00:02:45 +0200336 WARN_ON(!mutex_is_locked(&dev->object_name_lock));
Chris Wilson98a88832016-01-04 10:11:00 +0000337 if (obj->handle_count++ == 0)
338 drm_gem_object_reference(obj);
Daniel Vetter20228c42013-08-15 00:02:45 +0200339
Eric Anholt673a3942008-07-30 12:06:12 -0700340 /*
Tejun Heo2e928812013-02-27 17:04:08 -0800341 * Get the user-visible handle using idr. Preload and perform
342 * allocation under our spinlock.
Eric Anholt673a3942008-07-30 12:06:12 -0700343 */
Tejun Heo2e928812013-02-27 17:04:08 -0800344 idr_preload(GFP_KERNEL);
Eric Anholt673a3942008-07-30 12:06:12 -0700345 spin_lock(&file_priv->table_lock);
Tejun Heo2e928812013-02-27 17:04:08 -0800346
347 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
Chris Wilson98a88832016-01-04 10:11:00 +0000348
Eric Anholt673a3942008-07-30 12:06:12 -0700349 spin_unlock(&file_priv->table_lock);
Tejun Heo2e928812013-02-27 17:04:08 -0800350 idr_preload_end();
Chris Wilson98a88832016-01-04 10:11:00 +0000351
Daniel Vettercd4f0132013-08-15 00:02:44 +0200352 mutex_unlock(&dev->object_name_lock);
Chris Wilson69841282016-01-04 10:10:59 +0000353 if (ret < 0)
354 goto err_unref;
355
Tejun Heo2e928812013-02-27 17:04:08 -0800356 *handlep = ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700357
David Herrmannca481c92013-08-25 18:28:58 +0200358 ret = drm_vma_node_allow(&obj->vma_node, file_priv->filp);
Chris Wilson69841282016-01-04 10:10:59 +0000359 if (ret)
360 goto err_remove;
Ben Skeggs304eda32011-06-09 00:24:59 +0000361
362 if (dev->driver->gem_open_object) {
363 ret = dev->driver->gem_open_object(obj, file_priv);
Chris Wilson69841282016-01-04 10:10:59 +0000364 if (ret)
365 goto err_revoke;
Ben Skeggs304eda32011-06-09 00:24:59 +0000366 }
367
Eric Anholt673a3942008-07-30 12:06:12 -0700368 return 0;
Chris Wilson69841282016-01-04 10:10:59 +0000369
370err_revoke:
371 drm_vma_node_revoke(&obj->vma_node, file_priv->filp);
372err_remove:
373 spin_lock(&file_priv->table_lock);
374 idr_remove(&file_priv->object_idr, *handlep);
375 spin_unlock(&file_priv->table_lock);
376err_unref:
377 drm_gem_object_handle_unreference_unlocked(obj);
378 return ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700379}
Daniel Vetter20228c42013-08-15 00:02:45 +0200380
381/**
Thierry Reding8bf81802014-11-03 13:20:52 +0100382 * drm_gem_handle_create - create a gem handle for an object
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100383 * @file_priv: drm file-private structure to register the handle for
384 * @obj: object to register
385 * @handlep: pionter to return the created handle to the caller
386 *
Daniel Vetter20228c42013-08-15 00:02:45 +0200387 * Create a handle for this object. This adds a handle reference
388 * to the object, which includes a regular reference count. Callers
389 * will likely want to dereference the object afterwards.
390 */
Thierry Reding8bf81802014-11-03 13:20:52 +0100391int drm_gem_handle_create(struct drm_file *file_priv,
392 struct drm_gem_object *obj,
393 u32 *handlep)
Daniel Vetter20228c42013-08-15 00:02:45 +0200394{
395 mutex_lock(&obj->dev->object_name_lock);
396
397 return drm_gem_handle_create_tail(file_priv, obj, handlep);
398}
Eric Anholt673a3942008-07-30 12:06:12 -0700399EXPORT_SYMBOL(drm_gem_handle_create);
400
Rob Clark75ef8b32011-08-10 08:09:07 -0500401
402/**
403 * drm_gem_free_mmap_offset - release a fake mmap offset for an object
404 * @obj: obj in question
405 *
406 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset().
407 */
408void
409drm_gem_free_mmap_offset(struct drm_gem_object *obj)
410{
411 struct drm_device *dev = obj->dev;
Rob Clark75ef8b32011-08-10 08:09:07 -0500412
Daniel Vetterb04a5902013-12-11 14:24:46 +0100413 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node);
Rob Clark75ef8b32011-08-10 08:09:07 -0500414}
415EXPORT_SYMBOL(drm_gem_free_mmap_offset);
416
417/**
Rob Clark367bbd42013-08-07 13:41:23 -0400418 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object
419 * @obj: obj in question
420 * @size: the virtual size
421 *
422 * GEM memory mapping works by handing back to userspace a fake mmap offset
423 * it can use in a subsequent mmap(2) call. The DRM core code then looks
424 * up the object based on the offset and sets up the various memory mapping
425 * structures.
426 *
427 * This routine allocates and attaches a fake offset for @obj, in cases where
428 * the virtual size differs from the physical size (ie. obj->size). Otherwise
429 * just use drm_gem_create_mmap_offset().
430 */
431int
432drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size)
433{
434 struct drm_device *dev = obj->dev;
Rob Clark367bbd42013-08-07 13:41:23 -0400435
Daniel Vetterb04a5902013-12-11 14:24:46 +0100436 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node,
Rob Clark367bbd42013-08-07 13:41:23 -0400437 size / PAGE_SIZE);
438}
439EXPORT_SYMBOL(drm_gem_create_mmap_offset_size);
440
441/**
Rob Clark75ef8b32011-08-10 08:09:07 -0500442 * drm_gem_create_mmap_offset - create a fake mmap offset for an object
443 * @obj: obj in question
444 *
445 * GEM memory mapping works by handing back to userspace a fake mmap offset
446 * it can use in a subsequent mmap(2) call. The DRM core code then looks
447 * up the object based on the offset and sets up the various memory mapping
448 * structures.
449 *
450 * This routine allocates and attaches a fake offset for @obj.
451 */
Rob Clark367bbd42013-08-07 13:41:23 -0400452int drm_gem_create_mmap_offset(struct drm_gem_object *obj)
Rob Clark75ef8b32011-08-10 08:09:07 -0500453{
Rob Clark367bbd42013-08-07 13:41:23 -0400454 return drm_gem_create_mmap_offset_size(obj, obj->size);
Rob Clark75ef8b32011-08-10 08:09:07 -0500455}
456EXPORT_SYMBOL(drm_gem_create_mmap_offset);
457
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400458/**
459 * drm_gem_get_pages - helper to allocate backing pages for a GEM object
460 * from shmem
461 * @obj: obj in question
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200462 *
463 * This reads the page-array of the shmem-backing storage of the given gem
464 * object. An array of pages is returned. If a page is not allocated or
465 * swapped-out, this will allocate/swap-in the required pages. Note that the
466 * whole object is covered by the page-array and pinned in memory.
467 *
468 * Use drm_gem_put_pages() to release the array and unpin all pages.
469 *
470 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()).
471 * If you require other GFP-masks, you have to do those allocations yourself.
472 *
473 * Note that you are not allowed to change gfp-zones during runtime. That is,
474 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as
475 * set during initialization. If you have special zone constraints, set them
476 * after drm_gem_init_object() via mapping_set_gfp_mask(). shmem-core takes care
477 * to keep pages in the required zone during swap-in.
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400478 */
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200479struct page **drm_gem_get_pages(struct drm_gem_object *obj)
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400480{
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400481 struct address_space *mapping;
482 struct page *p, **pages;
483 int i, npages;
484
485 /* This is the shared memory object that backs the GEM resource */
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200486 mapping = file_inode(obj->filp)->i_mapping;
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400487
488 /* We already BUG_ON() for non-page-aligned sizes in
489 * drm_gem_object_init(), so we should never hit this unless
490 * driver author is doing something really wrong:
491 */
492 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
493
494 npages = obj->size >> PAGE_SHIFT;
495
496 pages = drm_malloc_ab(npages, sizeof(struct page *));
497 if (pages == NULL)
498 return ERR_PTR(-ENOMEM);
499
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400500 for (i = 0; i < npages; i++) {
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200501 p = shmem_read_mapping_page(mapping, i);
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400502 if (IS_ERR(p))
503 goto fail;
504 pages[i] = p;
505
David Herrmann21230002014-05-25 14:34:08 +0200506 /* Make sure shmem keeps __GFP_DMA32 allocated pages in the
507 * correct region during swapin. Note that this requires
508 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping)
509 * so shmem can relocate pages during swapin if required.
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400510 */
Michal Hockoc62d2552015-11-06 16:28:49 -0800511 BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) &&
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400512 (page_to_pfn(p) >= 0x00100000UL));
513 }
514
515 return pages;
516
517fail:
518 while (i--)
519 page_cache_release(pages[i]);
520
521 drm_free_large(pages);
522 return ERR_CAST(p);
523}
524EXPORT_SYMBOL(drm_gem_get_pages);
525
526/**
527 * drm_gem_put_pages - helper to free backing pages for a GEM object
528 * @obj: obj in question
529 * @pages: pages to free
530 * @dirty: if true, pages will be marked as dirty
531 * @accessed: if true, the pages will be marked as accessed
532 */
533void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
534 bool dirty, bool accessed)
535{
536 int i, npages;
537
538 /* We already BUG_ON() for non-page-aligned sizes in
539 * drm_gem_object_init(), so we should never hit this unless
540 * driver author is doing something really wrong:
541 */
542 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
543
544 npages = obj->size >> PAGE_SHIFT;
545
546 for (i = 0; i < npages; i++) {
547 if (dirty)
548 set_page_dirty(pages[i]);
549
550 if (accessed)
551 mark_page_accessed(pages[i]);
552
553 /* Undo the reference we took when populating the table */
554 page_cache_release(pages[i]);
555 }
556
557 drm_free_large(pages);
558}
559EXPORT_SYMBOL(drm_gem_put_pages);
560
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200561/**
562 * drm_gem_object_lookup - look up a GEM object from it's handle
563 * @dev: DRM device
564 * @filp: DRM file private date
565 * @handle: userspace handle
566 *
567 * Returns:
568 *
569 * A reference to the object named by the handle if such exists on @filp, NULL
570 * otherwise.
571 */
Eric Anholt673a3942008-07-30 12:06:12 -0700572struct drm_gem_object *
573drm_gem_object_lookup(struct drm_device *dev, struct drm_file *filp,
Pekka Paalanena1a2d1d2009-08-23 12:40:55 +0300574 u32 handle)
Eric Anholt673a3942008-07-30 12:06:12 -0700575{
576 struct drm_gem_object *obj;
577
578 spin_lock(&filp->table_lock);
579
580 /* Check if we currently have a reference on the object */
581 obj = idr_find(&filp->object_idr, handle);
582 if (obj == NULL) {
583 spin_unlock(&filp->table_lock);
584 return NULL;
585 }
586
587 drm_gem_object_reference(obj);
588
589 spin_unlock(&filp->table_lock);
590
591 return obj;
592}
593EXPORT_SYMBOL(drm_gem_object_lookup);
594
595/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100596 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
597 * @dev: drm_device
598 * @data: ioctl data
599 * @file_priv: drm file-private structure
600 *
Eric Anholt673a3942008-07-30 12:06:12 -0700601 * Releases the handle to an mm object.
602 */
603int
604drm_gem_close_ioctl(struct drm_device *dev, void *data,
605 struct drm_file *file_priv)
606{
607 struct drm_gem_close *args = data;
608 int ret;
609
Andrzej Hajda1bcecfa2014-09-30 16:49:56 +0200610 if (!drm_core_check_feature(dev, DRIVER_GEM))
Eric Anholt673a3942008-07-30 12:06:12 -0700611 return -ENODEV;
612
613 ret = drm_gem_handle_delete(file_priv, args->handle);
614
615 return ret;
616}
617
618/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100619 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
620 * @dev: drm_device
621 * @data: ioctl data
622 * @file_priv: drm file-private structure
623 *
Eric Anholt673a3942008-07-30 12:06:12 -0700624 * Create a global name for an object, returning the name.
625 *
626 * Note that the name does not hold a reference; when the object
627 * is freed, the name goes away.
628 */
629int
630drm_gem_flink_ioctl(struct drm_device *dev, void *data,
631 struct drm_file *file_priv)
632{
633 struct drm_gem_flink *args = data;
634 struct drm_gem_object *obj;
635 int ret;
636
Andrzej Hajda1bcecfa2014-09-30 16:49:56 +0200637 if (!drm_core_check_feature(dev, DRIVER_GEM))
Eric Anholt673a3942008-07-30 12:06:12 -0700638 return -ENODEV;
639
640 obj = drm_gem_object_lookup(dev, file_priv, args->handle);
641 if (obj == NULL)
Chris Wilsonbf79cb92010-08-04 14:19:46 +0100642 return -ENOENT;
Eric Anholt673a3942008-07-30 12:06:12 -0700643
Daniel Vettercd4f0132013-08-15 00:02:44 +0200644 mutex_lock(&dev->object_name_lock);
Tejun Heo2e928812013-02-27 17:04:08 -0800645 idr_preload(GFP_KERNEL);
Daniel Vettera8e11d12013-08-15 00:02:37 +0200646 /* prevent races with concurrent gem_close. */
647 if (obj->handle_count == 0) {
648 ret = -ENOENT;
649 goto err;
650 }
651
Chris Wilson8d59bae2009-02-11 14:26:28 +0000652 if (!obj->name) {
Tejun Heo2e928812013-02-27 17:04:08 -0800653 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_NOWAIT);
Tejun Heo2e928812013-02-27 17:04:08 -0800654 if (ret < 0)
Chris Wilson8d59bae2009-02-11 14:26:28 +0000655 goto err;
YoungJun Cho2e07fb22013-06-27 08:58:33 +0900656
657 obj->name = ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700658 }
Chris Wilson3e49c4f2009-02-09 11:31:41 +0000659
YoungJun Cho2e07fb22013-06-27 08:58:33 +0900660 args->name = (uint64_t) obj->name;
661 ret = 0;
662
Chris Wilson3e49c4f2009-02-09 11:31:41 +0000663err:
YoungJun Cho2e07fb22013-06-27 08:58:33 +0900664 idr_preload_end();
Daniel Vettercd4f0132013-08-15 00:02:44 +0200665 mutex_unlock(&dev->object_name_lock);
Luca Barbieribc9025b2010-02-09 05:49:12 +0000666 drm_gem_object_unreference_unlocked(obj);
Chris Wilson3e49c4f2009-02-09 11:31:41 +0000667 return ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700668}
669
670/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100671 * drm_gem_open - implementation of the GEM_OPEN ioctl
672 * @dev: drm_device
673 * @data: ioctl data
674 * @file_priv: drm file-private structure
675 *
Eric Anholt673a3942008-07-30 12:06:12 -0700676 * Open an object using the global name, returning a handle and the size.
677 *
678 * This handle (of course) holds a reference to the object, so the object
679 * will not go away until the handle is deleted.
680 */
681int
682drm_gem_open_ioctl(struct drm_device *dev, void *data,
683 struct drm_file *file_priv)
684{
685 struct drm_gem_open *args = data;
686 struct drm_gem_object *obj;
687 int ret;
Pekka Paalanena1a2d1d2009-08-23 12:40:55 +0300688 u32 handle;
Eric Anholt673a3942008-07-30 12:06:12 -0700689
Andrzej Hajda1bcecfa2014-09-30 16:49:56 +0200690 if (!drm_core_check_feature(dev, DRIVER_GEM))
Eric Anholt673a3942008-07-30 12:06:12 -0700691 return -ENODEV;
692
Daniel Vettercd4f0132013-08-15 00:02:44 +0200693 mutex_lock(&dev->object_name_lock);
Eric Anholt673a3942008-07-30 12:06:12 -0700694 obj = idr_find(&dev->object_name_idr, (int) args->name);
Daniel Vetter20228c42013-08-15 00:02:45 +0200695 if (obj) {
Eric Anholt673a3942008-07-30 12:06:12 -0700696 drm_gem_object_reference(obj);
Daniel Vetter20228c42013-08-15 00:02:45 +0200697 } else {
698 mutex_unlock(&dev->object_name_lock);
Eric Anholt673a3942008-07-30 12:06:12 -0700699 return -ENOENT;
Daniel Vetter20228c42013-08-15 00:02:45 +0200700 }
Eric Anholt673a3942008-07-30 12:06:12 -0700701
Daniel Vetter20228c42013-08-15 00:02:45 +0200702 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */
703 ret = drm_gem_handle_create_tail(file_priv, obj, &handle);
Luca Barbieribc9025b2010-02-09 05:49:12 +0000704 drm_gem_object_unreference_unlocked(obj);
Eric Anholt673a3942008-07-30 12:06:12 -0700705 if (ret)
706 return ret;
707
708 args->handle = handle;
709 args->size = obj->size;
710
711 return 0;
712}
713
714/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100715 * gem_gem_open - initalizes GEM file-private structures at devnode open time
716 * @dev: drm_device which is being opened by userspace
717 * @file_private: drm file-private structure to set up
718 *
Eric Anholt673a3942008-07-30 12:06:12 -0700719 * Called at device open time, sets up the structure for handling refcounting
720 * of mm objects.
721 */
722void
723drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
724{
725 idr_init(&file_private->object_idr);
726 spin_lock_init(&file_private->table_lock);
727}
728
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100729/*
Eric Anholt673a3942008-07-30 12:06:12 -0700730 * Called at device close to release the file's
731 * handle references on objects.
732 */
733static int
734drm_gem_object_release_handle(int id, void *ptr, void *data)
735{
Ben Skeggs304eda32011-06-09 00:24:59 +0000736 struct drm_file *file_priv = data;
Eric Anholt673a3942008-07-30 12:06:12 -0700737 struct drm_gem_object *obj = ptr;
Ben Skeggs304eda32011-06-09 00:24:59 +0000738 struct drm_device *dev = obj->dev;
739
Thierry Reding9c784852013-08-28 12:04:14 +0200740 if (drm_core_check_feature(dev, DRIVER_PRIME))
741 drm_gem_remove_prime_handles(obj, file_priv);
David Herrmannca481c92013-08-25 18:28:58 +0200742 drm_vma_node_revoke(&obj->vma_node, file_priv->filp);
Dave Airlie32488772011-11-25 15:21:02 +0000743
Ben Skeggs304eda32011-06-09 00:24:59 +0000744 if (dev->driver->gem_close_object)
745 dev->driver->gem_close_object(obj, file_priv);
Eric Anholt673a3942008-07-30 12:06:12 -0700746
Luca Barbieribc9025b2010-02-09 05:49:12 +0000747 drm_gem_object_handle_unreference_unlocked(obj);
Eric Anholt673a3942008-07-30 12:06:12 -0700748
749 return 0;
750}
751
752/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100753 * drm_gem_release - release file-private GEM resources
754 * @dev: drm_device which is being closed by userspace
755 * @file_private: drm file-private structure to clean up
756 *
Eric Anholt673a3942008-07-30 12:06:12 -0700757 * Called at close time when the filp is going away.
758 *
759 * Releases any remaining references on objects by this filp.
760 */
761void
762drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
763{
Eric Anholt673a3942008-07-30 12:06:12 -0700764 idr_for_each(&file_private->object_idr,
Ben Skeggs304eda32011-06-09 00:24:59 +0000765 &drm_gem_object_release_handle, file_private);
Eric Anholt673a3942008-07-30 12:06:12 -0700766 idr_destroy(&file_private->object_idr);
Eric Anholt673a3942008-07-30 12:06:12 -0700767}
768
Daniel Vetterfd632aa2010-04-09 19:05:05 +0000769void
770drm_gem_object_release(struct drm_gem_object *obj)
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000771{
Daniel Vetter319c9332013-08-15 00:02:46 +0200772 WARN_ON(obj->dma_buf);
773
Alan Cox62cb70112011-06-07 14:17:51 +0100774 if (obj->filp)
David Herrmann16d28312014-01-20 20:07:49 +0100775 fput(obj->filp);
David Herrmann77472342014-01-20 20:05:43 +0100776
777 drm_gem_free_mmap_offset(obj);
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000778}
Daniel Vetterfd632aa2010-04-09 19:05:05 +0000779EXPORT_SYMBOL(drm_gem_object_release);
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000780
Eric Anholt673a3942008-07-30 12:06:12 -0700781/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100782 * drm_gem_object_free - free a GEM object
783 * @kref: kref of the object to free
784 *
Eric Anholt673a3942008-07-30 12:06:12 -0700785 * Called after the last reference to the object has been lost.
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000786 * Must be called holding struct_ mutex
Eric Anholt673a3942008-07-30 12:06:12 -0700787 *
788 * Frees the object
789 */
790void
791drm_gem_object_free(struct kref *kref)
792{
Daniel Vetter6ff774b2015-10-15 09:36:26 +0200793 struct drm_gem_object *obj =
794 container_of(kref, struct drm_gem_object, refcount);
Eric Anholt673a3942008-07-30 12:06:12 -0700795 struct drm_device *dev = obj->dev;
796
Daniel Vetter8d77a942015-07-09 23:32:35 +0200797 WARN_ON(!mutex_is_locked(&dev->struct_mutex));
Eric Anholt673a3942008-07-30 12:06:12 -0700798
799 if (dev->driver->gem_free_object != NULL)
800 dev->driver->gem_free_object(obj);
Eric Anholt673a3942008-07-30 12:06:12 -0700801}
802EXPORT_SYMBOL(drm_gem_object_free);
803
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200804/**
805 * drm_gem_vm_open - vma->ops->open implementation for GEM
806 * @vma: VM area structure
807 *
808 * This function implements the #vm_operations_struct open() callback for GEM
809 * drivers. This must be used together with drm_gem_vm_close().
810 */
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800811void drm_gem_vm_open(struct vm_area_struct *vma)
812{
813 struct drm_gem_object *obj = vma->vm_private_data;
814
815 drm_gem_object_reference(obj);
816}
817EXPORT_SYMBOL(drm_gem_vm_open);
818
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200819/**
820 * drm_gem_vm_close - vma->ops->close implementation for GEM
821 * @vma: VM area structure
822 *
823 * This function implements the #vm_operations_struct close() callback for GEM
824 * drivers. This must be used together with drm_gem_vm_open().
825 */
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800826void drm_gem_vm_close(struct vm_area_struct *vma)
827{
828 struct drm_gem_object *obj = vma->vm_private_data;
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800829
Daniel Vetter131e6632015-07-09 23:32:33 +0200830 drm_gem_object_unreference_unlocked(obj);
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800831}
832EXPORT_SYMBOL(drm_gem_vm_close);
833
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200834/**
835 * drm_gem_mmap_obj - memory map a GEM object
836 * @obj: the GEM object to map
837 * @obj_size: the object size to be mapped, in bytes
838 * @vma: VMA for the area to be mapped
839 *
840 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops
841 * provided by the driver. Depending on their requirements, drivers can either
842 * provide a fault handler in their gem_vm_ops (in which case any accesses to
843 * the object will be trapped, to perform migration, GTT binding, surface
844 * register allocation, or performance monitoring), or mmap the buffer memory
845 * synchronously after calling drm_gem_mmap_obj.
846 *
847 * This function is mainly intended to implement the DMABUF mmap operation, when
848 * the GEM object is not looked up based on its fake offset. To implement the
849 * DRM mmap operation, drivers should use the drm_gem_mmap() function.
850 *
David Herrmannca481c92013-08-25 18:28:58 +0200851 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while
852 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So
853 * callers must verify access restrictions before calling this helper.
854 *
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200855 * Return 0 or success or -EINVAL if the object size is smaller than the VMA
856 * size, or if no gem_vm_ops are provided.
857 */
858int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
859 struct vm_area_struct *vma)
860{
861 struct drm_device *dev = obj->dev;
862
863 /* Check for valid size. */
864 if (obj_size < vma->vm_end - vma->vm_start)
865 return -EINVAL;
866
867 if (!dev->driver->gem_vm_ops)
868 return -EINVAL;
869
870 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
871 vma->vm_ops = dev->driver->gem_vm_ops;
872 vma->vm_private_data = obj;
David Herrmann16d28312014-01-20 20:07:49 +0100873 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200874
875 /* Take a ref for this mapping of the object, so that the fault
876 * handler can dereference the mmap offset's pointer to the object.
877 * This reference is cleaned up by the corresponding vm_close
878 * (which should happen whether the vma was created by this call, or
879 * by a vm_open due to mremap or partial unmap or whatever).
880 */
881 drm_gem_object_reference(obj);
882
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200883 return 0;
884}
885EXPORT_SYMBOL(drm_gem_mmap_obj);
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800886
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800887/**
888 * drm_gem_mmap - memory map routine for GEM objects
889 * @filp: DRM file pointer
890 * @vma: VMA for the area to be mapped
891 *
892 * If a driver supports GEM object mapping, mmap calls on the DRM file
893 * descriptor will end up here.
894 *
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200895 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800896 * contain the fake offset we created when the GTT map ioctl was called on
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200897 * the object) and map it with a call to drm_gem_mmap_obj().
David Herrmannca481c92013-08-25 18:28:58 +0200898 *
899 * If the caller is not granted access to the buffer object, the mmap will fail
900 * with EACCES. Please see the vma manager for more information.
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800901 */
902int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
903{
904 struct drm_file *priv = filp->private_data;
905 struct drm_device *dev = priv->minor->dev;
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200906 struct drm_gem_object *obj = NULL;
David Herrmann0de23972013-07-24 21:07:52 +0200907 struct drm_vma_offset_node *node;
David Herrmanna8469aa2014-01-20 20:15:38 +0100908 int ret;
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800909
Dave Airlie2c07a212012-02-20 14:18:07 +0000910 if (drm_device_is_unplugged(dev))
911 return -ENODEV;
912
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200913 drm_vma_offset_lock_lookup(dev->vma_offset_manager);
914 node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,
915 vma->vm_pgoff,
916 vma_pages(vma));
917 if (likely(node)) {
918 obj = container_of(node, struct drm_gem_object, vma_node);
919 /*
920 * When the object is being freed, after it hits 0-refcnt it
921 * proceeds to tear down the object. In the process it will
922 * attempt to remove the VMA offset and so acquire this
923 * mgr->vm_lock. Therefore if we find an object with a 0-refcnt
924 * that matches our range, we know it is in the process of being
925 * destroyed and will be freed as soon as we release the lock -
926 * so we have to check for the 0-refcnted object and treat it as
927 * invalid.
928 */
929 if (!kref_get_unless_zero(&obj->refcount))
930 obj = NULL;
931 }
932 drm_vma_offset_unlock_lookup(dev->vma_offset_manager);
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800933
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200934 if (!obj)
Daniel Vetter197633b2014-09-23 15:46:48 +0200935 return -EINVAL;
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200936
937 if (!drm_vma_node_is_allowed(node, filp)) {
938 drm_gem_object_unreference_unlocked(obj);
David Herrmannca481c92013-08-25 18:28:58 +0200939 return -EACCES;
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800940 }
941
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200942 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT,
943 vma);
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800944
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200945 drm_gem_object_unreference_unlocked(obj);
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800946
947 return ret;
948}
949EXPORT_SYMBOL(drm_gem_mmap);