blob: 465bacd0a630455e72c3127e12a000cad80ca4db [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
Chris Wilson8815b232016-01-05 09:42:31 +0000247/*
248 * Called at device or object close to release the file's
249 * handle references on objects.
250 */
251static int
252drm_gem_object_release_handle(int id, void *ptr, void *data)
253{
254 struct drm_file *file_priv = data;
255 struct drm_gem_object *obj = ptr;
256 struct drm_device *dev = obj->dev;
257
258 if (drm_core_check_feature(dev, DRIVER_PRIME))
259 drm_gem_remove_prime_handles(obj, file_priv);
David Herrmannd9a1f0b2016-09-01 14:48:33 +0200260 drm_vma_node_revoke(&obj->vma_node, file_priv);
Chris Wilson8815b232016-01-05 09:42:31 +0000261
262 if (dev->driver->gem_close_object)
263 dev->driver->gem_close_object(obj, file_priv);
264
265 drm_gem_object_handle_unreference_unlocked(obj);
266
267 return 0;
268}
269
Eric Anholt673a3942008-07-30 12:06:12 -0700270/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100271 * drm_gem_handle_delete - deletes the given file-private handle
272 * @filp: drm file-private structure to use for the handle look up
273 * @handle: userspace handle to delete
274 *
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200275 * Removes the GEM handle from the @filp lookup table which has been added with
276 * drm_gem_handle_create(). If this is the last handle also cleans up linked
277 * resources like GEM names.
Eric Anholt673a3942008-07-30 12:06:12 -0700278 */
Dave Airlieff72145b2011-02-07 12:16:14 +1000279int
Pekka Paalanena1a2d1d2009-08-23 12:40:55 +0300280drm_gem_handle_delete(struct drm_file *filp, u32 handle)
Eric Anholt673a3942008-07-30 12:06:12 -0700281{
Eric Anholt673a3942008-07-30 12:06:12 -0700282 struct drm_gem_object *obj;
283
284 /* This is gross. The idr system doesn't let us try a delete and
285 * return an error code. It just spews if you fail at deleting.
286 * So, we have to grab a lock around finding the object and then
287 * doing the delete on it and dropping the refcount, or the user
288 * could race us to double-decrement the refcount and cause a
289 * use-after-free later. Given the frequency of our handle lookups,
290 * we may want to use ida for number allocation and a hash table
291 * for the pointers, anyway.
292 */
293 spin_lock(&filp->table_lock);
294
295 /* Check if we currently have a reference on the object */
Chris Wilsonf6cd7da2016-04-15 12:55:08 +0100296 obj = idr_replace(&filp->object_idr, NULL, handle);
297 spin_unlock(&filp->table_lock);
298 if (IS_ERR_OR_NULL(obj))
Eric Anholt673a3942008-07-30 12:06:12 -0700299 return -EINVAL;
Eric Anholt673a3942008-07-30 12:06:12 -0700300
Chris Wilsonf6cd7da2016-04-15 12:55:08 +0100301 /* Release driver's reference and decrement refcount. */
302 drm_gem_object_release_handle(handle, obj, filp);
303
304 /* And finally make the handle available for future allocations. */
305 spin_lock(&filp->table_lock);
Eric Anholt673a3942008-07-30 12:06:12 -0700306 idr_remove(&filp->object_idr, handle);
307 spin_unlock(&filp->table_lock);
308
Eric Anholt673a3942008-07-30 12:06:12 -0700309 return 0;
310}
Dave Airlieff72145b2011-02-07 12:16:14 +1000311EXPORT_SYMBOL(drm_gem_handle_delete);
Eric Anholt673a3942008-07-30 12:06:12 -0700312
313/**
Daniel Vetter43387b32013-07-16 09:12:04 +0200314 * drm_gem_dumb_destroy - dumb fb callback helper for gem based drivers
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100315 * @file: drm file-private structure to remove the dumb handle from
316 * @dev: corresponding drm_device
317 * @handle: the dumb handle to remove
Daniel Vetter43387b32013-07-16 09:12:04 +0200318 *
319 * This implements the ->dumb_destroy kms driver callback for drivers which use
320 * gem to manage their backing storage.
321 */
322int drm_gem_dumb_destroy(struct drm_file *file,
323 struct drm_device *dev,
324 uint32_t handle)
325{
326 return drm_gem_handle_delete(file, handle);
327}
328EXPORT_SYMBOL(drm_gem_dumb_destroy);
329
330/**
Daniel Vetter20228c42013-08-15 00:02:45 +0200331 * drm_gem_handle_create_tail - internal functions to create a handle
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100332 * @file_priv: drm file-private structure to register the handle for
333 * @obj: object to register
Thierry Reding8bf81802014-11-03 13:20:52 +0100334 * @handlep: pointer to return the created handle to the caller
Daniel Vetter20228c42013-08-15 00:02:45 +0200335 *
336 * This expects the dev->object_name_lock to be held already and will drop it
337 * before returning. Used to avoid races in establishing new handles when
338 * importing an object from either an flink name or a dma-buf.
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200339 *
340 * Handles must be release again through drm_gem_handle_delete(). This is done
341 * when userspace closes @file_priv for all attached handles, or through the
342 * GEM_CLOSE ioctl for individual handles.
Eric Anholt673a3942008-07-30 12:06:12 -0700343 */
344int
Daniel Vetter20228c42013-08-15 00:02:45 +0200345drm_gem_handle_create_tail(struct drm_file *file_priv,
346 struct drm_gem_object *obj,
347 u32 *handlep)
Eric Anholt673a3942008-07-30 12:06:12 -0700348{
Ben Skeggs304eda32011-06-09 00:24:59 +0000349 struct drm_device *dev = obj->dev;
Chris Wilson96493992016-01-05 09:42:30 +0000350 u32 handle;
Ben Skeggs304eda32011-06-09 00:24:59 +0000351 int ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700352
Daniel Vetter20228c42013-08-15 00:02:45 +0200353 WARN_ON(!mutex_is_locked(&dev->object_name_lock));
Chris Wilson98a88832016-01-04 10:11:00 +0000354 if (obj->handle_count++ == 0)
355 drm_gem_object_reference(obj);
Daniel Vetter20228c42013-08-15 00:02:45 +0200356
Eric Anholt673a3942008-07-30 12:06:12 -0700357 /*
Tejun Heo2e928812013-02-27 17:04:08 -0800358 * Get the user-visible handle using idr. Preload and perform
359 * allocation under our spinlock.
Eric Anholt673a3942008-07-30 12:06:12 -0700360 */
Tejun Heo2e928812013-02-27 17:04:08 -0800361 idr_preload(GFP_KERNEL);
Eric Anholt673a3942008-07-30 12:06:12 -0700362 spin_lock(&file_priv->table_lock);
Tejun Heo2e928812013-02-27 17:04:08 -0800363
364 ret = idr_alloc(&file_priv->object_idr, obj, 1, 0, GFP_NOWAIT);
Chris Wilson98a88832016-01-04 10:11:00 +0000365
Eric Anholt673a3942008-07-30 12:06:12 -0700366 spin_unlock(&file_priv->table_lock);
Tejun Heo2e928812013-02-27 17:04:08 -0800367 idr_preload_end();
Chris Wilson98a88832016-01-04 10:11:00 +0000368
Daniel Vettercd4f0132013-08-15 00:02:44 +0200369 mutex_unlock(&dev->object_name_lock);
Chris Wilson69841282016-01-04 10:10:59 +0000370 if (ret < 0)
371 goto err_unref;
372
Chris Wilson96493992016-01-05 09:42:30 +0000373 handle = ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700374
David Herrmannd9a1f0b2016-09-01 14:48:33 +0200375 ret = drm_vma_node_allow(&obj->vma_node, file_priv);
Chris Wilson69841282016-01-04 10:10:59 +0000376 if (ret)
377 goto err_remove;
Ben Skeggs304eda32011-06-09 00:24:59 +0000378
379 if (dev->driver->gem_open_object) {
380 ret = dev->driver->gem_open_object(obj, file_priv);
Chris Wilson69841282016-01-04 10:10:59 +0000381 if (ret)
382 goto err_revoke;
Ben Skeggs304eda32011-06-09 00:24:59 +0000383 }
384
Chris Wilson96493992016-01-05 09:42:30 +0000385 *handlep = handle;
Eric Anholt673a3942008-07-30 12:06:12 -0700386 return 0;
Chris Wilson69841282016-01-04 10:10:59 +0000387
388err_revoke:
David Herrmannd9a1f0b2016-09-01 14:48:33 +0200389 drm_vma_node_revoke(&obj->vma_node, file_priv);
Chris Wilson69841282016-01-04 10:10:59 +0000390err_remove:
391 spin_lock(&file_priv->table_lock);
Chris Wilson96493992016-01-05 09:42:30 +0000392 idr_remove(&file_priv->object_idr, handle);
Chris Wilson69841282016-01-04 10:10:59 +0000393 spin_unlock(&file_priv->table_lock);
394err_unref:
395 drm_gem_object_handle_unreference_unlocked(obj);
396 return ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700397}
Daniel Vetter20228c42013-08-15 00:02:45 +0200398
399/**
Thierry Reding8bf81802014-11-03 13:20:52 +0100400 * drm_gem_handle_create - create a gem handle for an object
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100401 * @file_priv: drm file-private structure to register the handle for
402 * @obj: object to register
403 * @handlep: pionter to return the created handle to the caller
404 *
Daniel Vetter20228c42013-08-15 00:02:45 +0200405 * Create a handle for this object. This adds a handle reference
406 * to the object, which includes a regular reference count. Callers
407 * will likely want to dereference the object afterwards.
408 */
Thierry Reding8bf81802014-11-03 13:20:52 +0100409int drm_gem_handle_create(struct drm_file *file_priv,
410 struct drm_gem_object *obj,
411 u32 *handlep)
Daniel Vetter20228c42013-08-15 00:02:45 +0200412{
413 mutex_lock(&obj->dev->object_name_lock);
414
415 return drm_gem_handle_create_tail(file_priv, obj, handlep);
416}
Eric Anholt673a3942008-07-30 12:06:12 -0700417EXPORT_SYMBOL(drm_gem_handle_create);
418
Rob Clark75ef8b32011-08-10 08:09:07 -0500419
420/**
421 * drm_gem_free_mmap_offset - release a fake mmap offset for an object
422 * @obj: obj in question
423 *
424 * This routine frees fake offsets allocated by drm_gem_create_mmap_offset().
Daniel Vetterf74418a2016-03-30 11:40:52 +0200425 *
426 * Note that drm_gem_object_release() already calls this function, so drivers
427 * don't have to take care of releasing the mmap offset themselves when freeing
428 * the GEM object.
Rob Clark75ef8b32011-08-10 08:09:07 -0500429 */
430void
431drm_gem_free_mmap_offset(struct drm_gem_object *obj)
432{
433 struct drm_device *dev = obj->dev;
Rob Clark75ef8b32011-08-10 08:09:07 -0500434
Daniel Vetterb04a5902013-12-11 14:24:46 +0100435 drm_vma_offset_remove(dev->vma_offset_manager, &obj->vma_node);
Rob Clark75ef8b32011-08-10 08:09:07 -0500436}
437EXPORT_SYMBOL(drm_gem_free_mmap_offset);
438
439/**
Rob Clark367bbd42013-08-07 13:41:23 -0400440 * drm_gem_create_mmap_offset_size - create a fake mmap offset for an object
441 * @obj: obj in question
442 * @size: the virtual size
443 *
444 * GEM memory mapping works by handing back to userspace a fake mmap offset
445 * it can use in a subsequent mmap(2) call. The DRM core code then looks
446 * up the object based on the offset and sets up the various memory mapping
447 * structures.
448 *
449 * This routine allocates and attaches a fake offset for @obj, in cases where
450 * the virtual size differs from the physical size (ie. obj->size). Otherwise
451 * just use drm_gem_create_mmap_offset().
Daniel Vetterf74418a2016-03-30 11:40:52 +0200452 *
453 * This function is idempotent and handles an already allocated mmap offset
454 * transparently. Drivers do not need to check for this case.
Rob Clark367bbd42013-08-07 13:41:23 -0400455 */
456int
457drm_gem_create_mmap_offset_size(struct drm_gem_object *obj, size_t size)
458{
459 struct drm_device *dev = obj->dev;
Rob Clark367bbd42013-08-07 13:41:23 -0400460
Daniel Vetterb04a5902013-12-11 14:24:46 +0100461 return drm_vma_offset_add(dev->vma_offset_manager, &obj->vma_node,
Rob Clark367bbd42013-08-07 13:41:23 -0400462 size / PAGE_SIZE);
463}
464EXPORT_SYMBOL(drm_gem_create_mmap_offset_size);
465
466/**
Rob Clark75ef8b32011-08-10 08:09:07 -0500467 * drm_gem_create_mmap_offset - create a fake mmap offset for an object
468 * @obj: obj in question
469 *
470 * GEM memory mapping works by handing back to userspace a fake mmap offset
471 * it can use in a subsequent mmap(2) call. The DRM core code then looks
472 * up the object based on the offset and sets up the various memory mapping
473 * structures.
474 *
475 * This routine allocates and attaches a fake offset for @obj.
Daniel Vetterf74418a2016-03-30 11:40:52 +0200476 *
477 * Drivers can call drm_gem_free_mmap_offset() before freeing @obj to release
478 * the fake offset again.
Rob Clark75ef8b32011-08-10 08:09:07 -0500479 */
Rob Clark367bbd42013-08-07 13:41:23 -0400480int drm_gem_create_mmap_offset(struct drm_gem_object *obj)
Rob Clark75ef8b32011-08-10 08:09:07 -0500481{
Rob Clark367bbd42013-08-07 13:41:23 -0400482 return drm_gem_create_mmap_offset_size(obj, obj->size);
Rob Clark75ef8b32011-08-10 08:09:07 -0500483}
484EXPORT_SYMBOL(drm_gem_create_mmap_offset);
485
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400486/**
487 * drm_gem_get_pages - helper to allocate backing pages for a GEM object
488 * from shmem
489 * @obj: obj in question
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200490 *
491 * This reads the page-array of the shmem-backing storage of the given gem
492 * object. An array of pages is returned. If a page is not allocated or
493 * swapped-out, this will allocate/swap-in the required pages. Note that the
494 * whole object is covered by the page-array and pinned in memory.
495 *
496 * Use drm_gem_put_pages() to release the array and unpin all pages.
497 *
498 * This uses the GFP-mask set on the shmem-mapping (see mapping_set_gfp_mask()).
499 * If you require other GFP-masks, you have to do those allocations yourself.
500 *
501 * Note that you are not allowed to change gfp-zones during runtime. That is,
502 * shmem_read_mapping_page_gfp() must be called with the same gfp_zone(gfp) as
503 * set during initialization. If you have special zone constraints, set them
504 * after drm_gem_init_object() via mapping_set_gfp_mask(). shmem-core takes care
505 * to keep pages in the required zone during swap-in.
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400506 */
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200507struct page **drm_gem_get_pages(struct drm_gem_object *obj)
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400508{
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400509 struct address_space *mapping;
510 struct page *p, **pages;
511 int i, npages;
512
513 /* This is the shared memory object that backs the GEM resource */
Al Viro93c76a32015-12-04 23:45:44 -0500514 mapping = obj->filp->f_mapping;
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400515
516 /* We already BUG_ON() for non-page-aligned sizes in
517 * drm_gem_object_init(), so we should never hit this unless
518 * driver author is doing something really wrong:
519 */
520 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
521
522 npages = obj->size >> PAGE_SHIFT;
523
524 pages = drm_malloc_ab(npages, sizeof(struct page *));
525 if (pages == NULL)
526 return ERR_PTR(-ENOMEM);
527
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400528 for (i = 0; i < npages; i++) {
David Herrmann0cdbe8a2014-05-25 12:59:47 +0200529 p = shmem_read_mapping_page(mapping, i);
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400530 if (IS_ERR(p))
531 goto fail;
532 pages[i] = p;
533
David Herrmann21230002014-05-25 14:34:08 +0200534 /* Make sure shmem keeps __GFP_DMA32 allocated pages in the
535 * correct region during swapin. Note that this requires
536 * __GFP_DMA32 to be set in mapping_gfp_mask(inode->i_mapping)
537 * so shmem can relocate pages during swapin if required.
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400538 */
Michal Hockoc62d2552015-11-06 16:28:49 -0800539 BUG_ON(mapping_gfp_constraint(mapping, __GFP_DMA32) &&
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400540 (page_to_pfn(p) >= 0x00100000UL));
541 }
542
543 return pages;
544
545fail:
546 while (i--)
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300547 put_page(pages[i]);
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400548
549 drm_free_large(pages);
550 return ERR_CAST(p);
551}
552EXPORT_SYMBOL(drm_gem_get_pages);
553
554/**
555 * drm_gem_put_pages - helper to free backing pages for a GEM object
556 * @obj: obj in question
557 * @pages: pages to free
558 * @dirty: if true, pages will be marked as dirty
559 * @accessed: if true, the pages will be marked as accessed
560 */
561void drm_gem_put_pages(struct drm_gem_object *obj, struct page **pages,
562 bool dirty, bool accessed)
563{
564 int i, npages;
565
566 /* We already BUG_ON() for non-page-aligned sizes in
567 * drm_gem_object_init(), so we should never hit this unless
568 * driver author is doing something really wrong:
569 */
570 WARN_ON((obj->size & (PAGE_SIZE - 1)) != 0);
571
572 npages = obj->size >> PAGE_SHIFT;
573
574 for (i = 0; i < npages; i++) {
575 if (dirty)
576 set_page_dirty(pages[i]);
577
578 if (accessed)
579 mark_page_accessed(pages[i]);
580
581 /* Undo the reference we took when populating the table */
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300582 put_page(pages[i]);
Rob Clarkbcc5c9d2013-08-07 13:41:24 -0400583 }
584
585 drm_free_large(pages);
586}
587EXPORT_SYMBOL(drm_gem_put_pages);
588
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200589/**
590 * drm_gem_object_lookup - look up a GEM object from it's handle
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200591 * @filp: DRM file private date
592 * @handle: userspace handle
593 *
594 * Returns:
595 *
596 * A reference to the object named by the handle if such exists on @filp, NULL
597 * otherwise.
598 */
Eric Anholt673a3942008-07-30 12:06:12 -0700599struct drm_gem_object *
Chris Wilsona8ad0bd2016-05-09 11:04:54 +0100600drm_gem_object_lookup(struct drm_file *filp, u32 handle)
Eric Anholt673a3942008-07-30 12:06:12 -0700601{
602 struct drm_gem_object *obj;
603
604 spin_lock(&filp->table_lock);
605
606 /* Check if we currently have a reference on the object */
607 obj = idr_find(&filp->object_idr, handle);
Chris Wilsona8ad0bd2016-05-09 11:04:54 +0100608 if (obj)
609 drm_gem_object_reference(obj);
Eric Anholt673a3942008-07-30 12:06:12 -0700610
611 spin_unlock(&filp->table_lock);
612
613 return obj;
614}
615EXPORT_SYMBOL(drm_gem_object_lookup);
616
617/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100618 * drm_gem_close_ioctl - implementation of the GEM_CLOSE ioctl
619 * @dev: drm_device
620 * @data: ioctl data
621 * @file_priv: drm file-private structure
622 *
Eric Anholt673a3942008-07-30 12:06:12 -0700623 * Releases the handle to an mm object.
624 */
625int
626drm_gem_close_ioctl(struct drm_device *dev, void *data,
627 struct drm_file *file_priv)
628{
629 struct drm_gem_close *args = data;
630 int ret;
631
Andrzej Hajda1bcecfa2014-09-30 16:49:56 +0200632 if (!drm_core_check_feature(dev, DRIVER_GEM))
Eric Anholt673a3942008-07-30 12:06:12 -0700633 return -ENODEV;
634
635 ret = drm_gem_handle_delete(file_priv, args->handle);
636
637 return ret;
638}
639
640/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100641 * drm_gem_flink_ioctl - implementation of the GEM_FLINK ioctl
642 * @dev: drm_device
643 * @data: ioctl data
644 * @file_priv: drm file-private structure
645 *
Eric Anholt673a3942008-07-30 12:06:12 -0700646 * Create a global name for an object, returning the name.
647 *
648 * Note that the name does not hold a reference; when the object
649 * is freed, the name goes away.
650 */
651int
652drm_gem_flink_ioctl(struct drm_device *dev, void *data,
653 struct drm_file *file_priv)
654{
655 struct drm_gem_flink *args = data;
656 struct drm_gem_object *obj;
657 int ret;
658
Andrzej Hajda1bcecfa2014-09-30 16:49:56 +0200659 if (!drm_core_check_feature(dev, DRIVER_GEM))
Eric Anholt673a3942008-07-30 12:06:12 -0700660 return -ENODEV;
661
Chris Wilsona8ad0bd2016-05-09 11:04:54 +0100662 obj = drm_gem_object_lookup(file_priv, args->handle);
Eric Anholt673a3942008-07-30 12:06:12 -0700663 if (obj == NULL)
Chris Wilsonbf79cb92010-08-04 14:19:46 +0100664 return -ENOENT;
Eric Anholt673a3942008-07-30 12:06:12 -0700665
Daniel Vettercd4f0132013-08-15 00:02:44 +0200666 mutex_lock(&dev->object_name_lock);
Daniel Vettera8e11d12013-08-15 00:02:37 +0200667 /* prevent races with concurrent gem_close. */
668 if (obj->handle_count == 0) {
669 ret = -ENOENT;
670 goto err;
671 }
672
Chris Wilson8d59bae2009-02-11 14:26:28 +0000673 if (!obj->name) {
Chris Wilson0f646422016-01-04 10:11:01 +0000674 ret = idr_alloc(&dev->object_name_idr, obj, 1, 0, GFP_KERNEL);
Tejun Heo2e928812013-02-27 17:04:08 -0800675 if (ret < 0)
Chris Wilson8d59bae2009-02-11 14:26:28 +0000676 goto err;
YoungJun Cho2e07fb22013-06-27 08:58:33 +0900677
678 obj->name = ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700679 }
Chris Wilson3e49c4f2009-02-09 11:31:41 +0000680
YoungJun Cho2e07fb22013-06-27 08:58:33 +0900681 args->name = (uint64_t) obj->name;
682 ret = 0;
683
Chris Wilson3e49c4f2009-02-09 11:31:41 +0000684err:
Daniel Vettercd4f0132013-08-15 00:02:44 +0200685 mutex_unlock(&dev->object_name_lock);
Luca Barbieribc9025b2010-02-09 05:49:12 +0000686 drm_gem_object_unreference_unlocked(obj);
Chris Wilson3e49c4f2009-02-09 11:31:41 +0000687 return ret;
Eric Anholt673a3942008-07-30 12:06:12 -0700688}
689
690/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100691 * drm_gem_open - implementation of the GEM_OPEN ioctl
692 * @dev: drm_device
693 * @data: ioctl data
694 * @file_priv: drm file-private structure
695 *
Eric Anholt673a3942008-07-30 12:06:12 -0700696 * Open an object using the global name, returning a handle and the size.
697 *
698 * This handle (of course) holds a reference to the object, so the object
699 * will not go away until the handle is deleted.
700 */
701int
702drm_gem_open_ioctl(struct drm_device *dev, void *data,
703 struct drm_file *file_priv)
704{
705 struct drm_gem_open *args = data;
706 struct drm_gem_object *obj;
707 int ret;
Pekka Paalanena1a2d1d2009-08-23 12:40:55 +0300708 u32 handle;
Eric Anholt673a3942008-07-30 12:06:12 -0700709
Andrzej Hajda1bcecfa2014-09-30 16:49:56 +0200710 if (!drm_core_check_feature(dev, DRIVER_GEM))
Eric Anholt673a3942008-07-30 12:06:12 -0700711 return -ENODEV;
712
Daniel Vettercd4f0132013-08-15 00:02:44 +0200713 mutex_lock(&dev->object_name_lock);
Eric Anholt673a3942008-07-30 12:06:12 -0700714 obj = idr_find(&dev->object_name_idr, (int) args->name);
Daniel Vetter20228c42013-08-15 00:02:45 +0200715 if (obj) {
Eric Anholt673a3942008-07-30 12:06:12 -0700716 drm_gem_object_reference(obj);
Daniel Vetter20228c42013-08-15 00:02:45 +0200717 } else {
718 mutex_unlock(&dev->object_name_lock);
Eric Anholt673a3942008-07-30 12:06:12 -0700719 return -ENOENT;
Daniel Vetter20228c42013-08-15 00:02:45 +0200720 }
Eric Anholt673a3942008-07-30 12:06:12 -0700721
Daniel Vetter20228c42013-08-15 00:02:45 +0200722 /* drm_gem_handle_create_tail unlocks dev->object_name_lock. */
723 ret = drm_gem_handle_create_tail(file_priv, obj, &handle);
Luca Barbieribc9025b2010-02-09 05:49:12 +0000724 drm_gem_object_unreference_unlocked(obj);
Eric Anholt673a3942008-07-30 12:06:12 -0700725 if (ret)
726 return ret;
727
728 args->handle = handle;
729 args->size = obj->size;
730
731 return 0;
732}
733
734/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100735 * gem_gem_open - initalizes GEM file-private structures at devnode open time
736 * @dev: drm_device which is being opened by userspace
737 * @file_private: drm file-private structure to set up
738 *
Eric Anholt673a3942008-07-30 12:06:12 -0700739 * Called at device open time, sets up the structure for handling refcounting
740 * of mm objects.
741 */
742void
743drm_gem_open(struct drm_device *dev, struct drm_file *file_private)
744{
745 idr_init(&file_private->object_idr);
746 spin_lock_init(&file_private->table_lock);
747}
748
Eric Anholt673a3942008-07-30 12:06:12 -0700749/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100750 * drm_gem_release - release file-private GEM resources
751 * @dev: drm_device which is being closed by userspace
752 * @file_private: drm file-private structure to clean up
753 *
Eric Anholt673a3942008-07-30 12:06:12 -0700754 * Called at close time when the filp is going away.
755 *
756 * Releases any remaining references on objects by this filp.
757 */
758void
759drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
760{
Eric Anholt673a3942008-07-30 12:06:12 -0700761 idr_for_each(&file_private->object_idr,
Ben Skeggs304eda32011-06-09 00:24:59 +0000762 &drm_gem_object_release_handle, file_private);
Eric Anholt673a3942008-07-30 12:06:12 -0700763 idr_destroy(&file_private->object_idr);
Eric Anholt673a3942008-07-30 12:06:12 -0700764}
765
Daniel Vetterf74418a2016-03-30 11:40:52 +0200766/**
767 * drm_gem_object_release - release GEM buffer object resources
768 * @obj: GEM buffer object
769 *
770 * This releases any structures and resources used by @obj and is the invers of
771 * drm_gem_object_init().
772 */
Daniel Vetterfd632aa2010-04-09 19:05:05 +0000773void
774drm_gem_object_release(struct drm_gem_object *obj)
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000775{
Daniel Vetter319c9332013-08-15 00:02:46 +0200776 WARN_ON(obj->dma_buf);
777
Alan Cox62cb70112011-06-07 14:17:51 +0100778 if (obj->filp)
David Herrmann16d28312014-01-20 20:07:49 +0100779 fput(obj->filp);
David Herrmann77472342014-01-20 20:05:43 +0100780
781 drm_gem_free_mmap_offset(obj);
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000782}
Daniel Vetterfd632aa2010-04-09 19:05:05 +0000783EXPORT_SYMBOL(drm_gem_object_release);
Luca Barbieric3ae90c2010-02-09 05:49:11 +0000784
Eric Anholt673a3942008-07-30 12:06:12 -0700785/**
Daniel Vetter89d61fc2014-01-21 12:39:00 +0100786 * drm_gem_object_free - free a GEM object
787 * @kref: kref of the object to free
788 *
Eric Anholt673a3942008-07-30 12:06:12 -0700789 * Called after the last reference to the object has been lost.
Daniel Vetter2e7a5702016-06-01 23:40:36 +0200790 * Must be called holding &drm_device->struct_mutex.
Eric Anholt673a3942008-07-30 12:06:12 -0700791 *
792 * Frees the object
793 */
794void
795drm_gem_object_free(struct kref *kref)
796{
Daniel Vetter6ff774b2015-10-15 09:36:26 +0200797 struct drm_gem_object *obj =
798 container_of(kref, struct drm_gem_object, refcount);
Eric Anholt673a3942008-07-30 12:06:12 -0700799 struct drm_device *dev = obj->dev;
800
Daniel Vetter6d3e7fd2016-05-04 14:10:44 +0200801 if (dev->driver->gem_free_object_unlocked) {
Daniel Vetter9f0ba532016-05-02 10:40:51 +0200802 dev->driver->gem_free_object_unlocked(obj);
Daniel Vetter6d3e7fd2016-05-04 14:10:44 +0200803 } else if (dev->driver->gem_free_object) {
804 WARN_ON(!mutex_is_locked(&dev->struct_mutex));
805
Eric Anholt673a3942008-07-30 12:06:12 -0700806 dev->driver->gem_free_object(obj);
Daniel Vetter6d3e7fd2016-05-04 14:10:44 +0200807 }
Eric Anholt673a3942008-07-30 12:06:12 -0700808}
809EXPORT_SYMBOL(drm_gem_object_free);
810
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200811/**
Daniel Vetter9f0ba532016-05-02 10:40:51 +0200812 * drm_gem_object_unreference_unlocked - release a GEM BO reference
813 * @obj: GEM buffer object
814 *
815 * This releases a reference to @obj. Callers must not hold the
816 * dev->struct_mutex lock when calling this function.
817 *
818 * See also __drm_gem_object_unreference().
819 */
820void
821drm_gem_object_unreference_unlocked(struct drm_gem_object *obj)
822{
823 struct drm_device *dev;
824
825 if (!obj)
826 return;
827
828 dev = obj->dev;
829 might_lock(&dev->struct_mutex);
830
831 if (dev->driver->gem_free_object_unlocked)
832 kref_put(&obj->refcount, drm_gem_object_free);
833 else if (kref_put_mutex(&obj->refcount, drm_gem_object_free,
834 &dev->struct_mutex))
835 mutex_unlock(&dev->struct_mutex);
836}
837EXPORT_SYMBOL(drm_gem_object_unreference_unlocked);
838
839/**
840 * drm_gem_object_unreference - release a GEM BO reference
841 * @obj: GEM buffer object
842 *
843 * This releases a reference to @obj. Callers must hold the dev->struct_mutex
844 * lock when calling this function, even when the driver doesn't use
845 * dev->struct_mutex for anything.
846 *
847 * For drivers not encumbered with legacy locking use
848 * drm_gem_object_unreference_unlocked() instead.
849 */
850void
851drm_gem_object_unreference(struct drm_gem_object *obj)
852{
853 if (obj) {
854 WARN_ON(!mutex_is_locked(&obj->dev->struct_mutex));
855
856 kref_put(&obj->refcount, drm_gem_object_free);
857 }
858}
859EXPORT_SYMBOL(drm_gem_object_unreference);
860
861/**
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200862 * drm_gem_vm_open - vma->ops->open implementation for GEM
863 * @vma: VM area structure
864 *
865 * This function implements the #vm_operations_struct open() callback for GEM
866 * drivers. This must be used together with drm_gem_vm_close().
867 */
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800868void drm_gem_vm_open(struct vm_area_struct *vma)
869{
870 struct drm_gem_object *obj = vma->vm_private_data;
871
872 drm_gem_object_reference(obj);
873}
874EXPORT_SYMBOL(drm_gem_vm_open);
875
Daniel Vetterdf2e0902015-10-22 19:11:29 +0200876/**
877 * drm_gem_vm_close - vma->ops->close implementation for GEM
878 * @vma: VM area structure
879 *
880 * This function implements the #vm_operations_struct close() callback for GEM
881 * drivers. This must be used together with drm_gem_vm_open().
882 */
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800883void drm_gem_vm_close(struct vm_area_struct *vma)
884{
885 struct drm_gem_object *obj = vma->vm_private_data;
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800886
Daniel Vetter131e6632015-07-09 23:32:33 +0200887 drm_gem_object_unreference_unlocked(obj);
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800888}
889EXPORT_SYMBOL(drm_gem_vm_close);
890
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200891/**
892 * drm_gem_mmap_obj - memory map a GEM object
893 * @obj: the GEM object to map
894 * @obj_size: the object size to be mapped, in bytes
895 * @vma: VMA for the area to be mapped
896 *
897 * Set up the VMA to prepare mapping of the GEM object using the gem_vm_ops
898 * provided by the driver. Depending on their requirements, drivers can either
899 * provide a fault handler in their gem_vm_ops (in which case any accesses to
900 * the object will be trapped, to perform migration, GTT binding, surface
901 * register allocation, or performance monitoring), or mmap the buffer memory
902 * synchronously after calling drm_gem_mmap_obj.
903 *
904 * This function is mainly intended to implement the DMABUF mmap operation, when
905 * the GEM object is not looked up based on its fake offset. To implement the
906 * DRM mmap operation, drivers should use the drm_gem_mmap() function.
907 *
David Herrmannca481c92013-08-25 18:28:58 +0200908 * drm_gem_mmap_obj() assumes the user is granted access to the buffer while
909 * drm_gem_mmap() prevents unprivileged users from mapping random objects. So
910 * callers must verify access restrictions before calling this helper.
911 *
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200912 * Return 0 or success or -EINVAL if the object size is smaller than the VMA
913 * size, or if no gem_vm_ops are provided.
914 */
915int drm_gem_mmap_obj(struct drm_gem_object *obj, unsigned long obj_size,
916 struct vm_area_struct *vma)
917{
918 struct drm_device *dev = obj->dev;
919
920 /* Check for valid size. */
921 if (obj_size < vma->vm_end - vma->vm_start)
922 return -EINVAL;
923
924 if (!dev->driver->gem_vm_ops)
925 return -EINVAL;
926
927 vma->vm_flags |= VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP;
928 vma->vm_ops = dev->driver->gem_vm_ops;
929 vma->vm_private_data = obj;
David Herrmann16d28312014-01-20 20:07:49 +0100930 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200931
932 /* Take a ref for this mapping of the object, so that the fault
933 * handler can dereference the mmap offset's pointer to the object.
934 * This reference is cleaned up by the corresponding vm_close
935 * (which should happen whether the vma was created by this call, or
936 * by a vm_open due to mremap or partial unmap or whatever).
937 */
938 drm_gem_object_reference(obj);
939
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200940 return 0;
941}
942EXPORT_SYMBOL(drm_gem_mmap_obj);
Jesse Barnesab00b3e2009-02-11 14:01:46 -0800943
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800944/**
945 * drm_gem_mmap - memory map routine for GEM objects
946 * @filp: DRM file pointer
947 * @vma: VMA for the area to be mapped
948 *
949 * If a driver supports GEM object mapping, mmap calls on the DRM file
950 * descriptor will end up here.
951 *
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200952 * Look up the GEM object based on the offset passed in (vma->vm_pgoff will
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800953 * contain the fake offset we created when the GTT map ioctl was called on
Laurent Pinchart1c5aafa2013-04-16 14:14:52 +0200954 * the object) and map it with a call to drm_gem_mmap_obj().
David Herrmannca481c92013-08-25 18:28:58 +0200955 *
956 * If the caller is not granted access to the buffer object, the mmap will fail
957 * with EACCES. Please see the vma manager for more information.
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800958 */
959int drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
960{
961 struct drm_file *priv = filp->private_data;
962 struct drm_device *dev = priv->minor->dev;
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200963 struct drm_gem_object *obj = NULL;
David Herrmann0de23972013-07-24 21:07:52 +0200964 struct drm_vma_offset_node *node;
David Herrmanna8469aa2014-01-20 20:15:38 +0100965 int ret;
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800966
Dave Airlie2c07a212012-02-20 14:18:07 +0000967 if (drm_device_is_unplugged(dev))
968 return -ENODEV;
969
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200970 drm_vma_offset_lock_lookup(dev->vma_offset_manager);
971 node = drm_vma_offset_exact_lookup_locked(dev->vma_offset_manager,
972 vma->vm_pgoff,
973 vma_pages(vma));
974 if (likely(node)) {
975 obj = container_of(node, struct drm_gem_object, vma_node);
976 /*
977 * When the object is being freed, after it hits 0-refcnt it
978 * proceeds to tear down the object. In the process it will
979 * attempt to remove the VMA offset and so acquire this
980 * mgr->vm_lock. Therefore if we find an object with a 0-refcnt
981 * that matches our range, we know it is in the process of being
982 * destroyed and will be freed as soon as we release the lock -
983 * so we have to check for the 0-refcnted object and treat it as
984 * invalid.
985 */
986 if (!kref_get_unless_zero(&obj->refcount))
987 obj = NULL;
988 }
989 drm_vma_offset_unlock_lookup(dev->vma_offset_manager);
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800990
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200991 if (!obj)
Daniel Vetter197633b2014-09-23 15:46:48 +0200992 return -EINVAL;
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200993
David Herrmannd9a1f0b2016-09-01 14:48:33 +0200994 if (!drm_vma_node_is_allowed(node, priv)) {
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200995 drm_gem_object_unreference_unlocked(obj);
David Herrmannca481c92013-08-25 18:28:58 +0200996 return -EACCES;
Jesse Barnesa2c0a972008-11-05 10:31:53 -0800997 }
998
Daniel Vetter2225cfe2015-10-15 11:33:43 +0200999 ret = drm_gem_mmap_obj(obj, drm_vma_node_size(node) << PAGE_SHIFT,
1000 vma);
Jesse Barnesa2c0a972008-11-05 10:31:53 -08001001
Daniel Vetter2225cfe2015-10-15 11:33:43 +02001002 drm_gem_object_unreference_unlocked(obj);
Jesse Barnesa2c0a972008-11-05 10:31:53 -08001003
1004 return ret;
1005}
1006EXPORT_SYMBOL(drm_gem_mmap);