xref: /linux/include/drm/drm_file.h (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5)
1 /*
2  * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
3  * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
4  * Copyright (c) 2009-2010, Code Aurora Forum.
5  * All rights reserved.
6  *
7  * Author: Rickard E. (Rik) Faith <faith@valinux.com>
8  * Author: Gareth Hughes <gareth@valinux.com>
9  *
10  * Permission is hereby granted, free of charge, to any person obtaining a
11  * copy of this software and associated documentation files (the "Software"),
12  * to deal in the Software without restriction, including without limitation
13  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
14  * and/or sell copies of the Software, and to permit persons to whom the
15  * Software is furnished to do so, subject to the following conditions:
16  *
17  * The above copyright notice and this permission notice (including the next
18  * paragraph) shall be included in all copies or substantial portions of the
19  * Software.
20  *
21  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
22  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
23  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
24  * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
25  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
26  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
27  * OTHER DEALINGS IN THE SOFTWARE.
28  */
29 
30 #ifndef _DRM_FILE_H_
31 #define _DRM_FILE_H_
32 
33 #include <linux/types.h>
34 #include <linux/completion.h>
35 #include <linux/idr.h>
36 
37 #include <uapi/drm/drm.h>
38 
39 #include <drm/drm_prime.h>
40 
41 struct dma_fence;
42 struct drm_file;
43 struct drm_device;
44 struct drm_printer;
45 struct device;
46 struct file;
47 
48 extern struct xarray drm_minors_xa;
49 
50 /*
51  * FIXME: Not sure we want to have drm_minor here in the end, but to avoid
52  * header include loops we need it here for now.
53  */
54 
55 /* Note that the values of this enum are ABI (it determines
56  * /dev/dri/renderD* numbers).
57  *
58  * Setting DRM_MINOR_ACCEL to 32 gives enough space for more drm minors to
59  * be implemented before we hit any future
60  */
61 enum drm_minor_type {
62 	DRM_MINOR_PRIMARY = 0,
63 	DRM_MINOR_CONTROL = 1,
64 	DRM_MINOR_RENDER = 2,
65 	DRM_MINOR_ACCEL = 32,
66 };
67 
68 /**
69  * struct drm_minor - DRM device minor structure
70  *
71  * This structure represents a DRM minor number for device nodes in /dev.
72  * Entirely opaque to drivers and should never be inspected directly by drivers.
73  * Drivers instead should only interact with &struct drm_file and of course
74  * &struct drm_device, which is also where driver-private data and resources can
75  * be attached to.
76  */
77 struct drm_minor {
78 	/* private: */
79 	int index;			/* Minor device number */
80 	int type;                       /* Control or render or accel */
81 	struct device *kdev;		/* Linux device */
82 	struct drm_device *dev;
83 
84 	struct dentry *debugfs_symlink;
85 	struct dentry *debugfs_root;
86 };
87 
88 /**
89  * struct drm_pending_event - Event queued up for userspace to read
90  *
91  * This represents a DRM event. Drivers can use this as a generic completion
92  * mechanism, which supports kernel-internal &struct completion, &struct dma_fence
93  * and also the DRM-specific &struct drm_event delivery mechanism.
94  */
95 struct drm_pending_event {
96 	/**
97 	 * @completion:
98 	 *
99 	 * Optional pointer to a kernel internal completion signalled when
100 	 * drm_send_event() is called, useful to internally synchronize with
101 	 * nonblocking operations.
102 	 */
103 	struct completion *completion;
104 
105 	/**
106 	 * @completion_release:
107 	 *
108 	 * Optional callback currently only used by the atomic modeset helpers
109 	 * to clean up the reference count for the structure @completion is
110 	 * stored in.
111 	 */
112 	void (*completion_release)(struct completion *completion);
113 
114 	/**
115 	 * @event:
116 	 *
117 	 * Pointer to the actual event that should be sent to userspace to be
118 	 * read using drm_read(). Can be optional, since nowadays events are
119 	 * also used to signal kernel internal threads with @completion or DMA
120 	 * transactions using @fence.
121 	 */
122 	struct drm_event *event;
123 
124 	/**
125 	 * @fence:
126 	 *
127 	 * Optional DMA fence to unblock other hardware transactions which
128 	 * depend upon the nonblocking DRM operation this event represents.
129 	 */
130 	struct dma_fence *fence;
131 
132 	/**
133 	 * @file_priv:
134 	 *
135 	 * &struct drm_file where @event should be delivered to. Only set when
136 	 * @event is set.
137 	 */
138 	struct drm_file *file_priv;
139 
140 	/**
141 	 * @link:
142 	 *
143 	 * Double-linked list to keep track of this event. Can be used by the
144 	 * driver up to the point when it calls drm_send_event(), after that
145 	 * this list entry is owned by the core for its own book-keeping.
146 	 */
147 	struct list_head link;
148 
149 	/**
150 	 * @pending_link:
151 	 *
152 	 * Entry on &drm_file.pending_event_list, to keep track of all pending
153 	 * events for @file_priv, to allow correct unwinding of them when
154 	 * userspace closes the file before the event is delivered.
155 	 */
156 	struct list_head pending_link;
157 };
158 
159 /**
160  * struct drm_file - DRM file private data
161  *
162  * This structure tracks DRM state per open file descriptor.
163  */
164 struct drm_file {
165 	/**
166 	 * @authenticated:
167 	 *
168 	 * Whether the client is allowed to submit rendering, which for legacy
169 	 * nodes means it must be authenticated.
170 	 *
171 	 * See also the :ref:`section on primary nodes and authentication
172 	 * <drm_primary_node>`.
173 	 */
174 	bool authenticated;
175 
176 	/**
177 	 * @stereo_allowed:
178 	 *
179 	 * True when the client has asked us to expose stereo 3D mode flags.
180 	 */
181 	bool stereo_allowed;
182 
183 	/**
184 	 * @universal_planes:
185 	 *
186 	 * True if client understands CRTC primary planes and cursor planes
187 	 * in the plane list. Automatically set when @atomic is set.
188 	 */
189 	bool universal_planes;
190 
191 	/** @atomic: True if client understands atomic properties. */
192 	bool atomic;
193 
194 	/**
195 	 * @aspect_ratio_allowed:
196 	 *
197 	 * True, if client can handle picture aspect ratios, and has requested
198 	 * to pass this information along with the mode.
199 	 */
200 	bool aspect_ratio_allowed;
201 
202 	/**
203 	 * @writeback_connectors:
204 	 *
205 	 * True if client understands writeback connectors
206 	 */
207 	bool writeback_connectors;
208 
209 	/**
210 	 * @was_master:
211 	 *
212 	 * This client has or had, master capability. Protected by struct
213 	 * &drm_device.master_mutex.
214 	 *
215 	 * This is used to ensure that CAP_SYS_ADMIN is not enforced, if the
216 	 * client is or was master in the past.
217 	 */
218 	bool was_master;
219 
220 	/**
221 	 * @is_master:
222 	 *
223 	 * This client is the creator of @master. Protected by struct
224 	 * &drm_device.master_mutex.
225 	 *
226 	 * See also the :ref:`section on primary nodes and authentication
227 	 * <drm_primary_node>`.
228 	 */
229 	bool is_master;
230 
231 	/**
232 	 * @supports_virtualized_cursor_plane:
233 	 *
234 	 * This client is capable of handling the cursor plane with the
235 	 * restrictions imposed on it by the virtualized drivers.
236 	 *
237 	 * This implies that the cursor plane has to behave like a cursor
238 	 * i.e. track cursor movement. It also requires setting of the
239 	 * hotspot properties by the client on the cursor plane.
240 	 */
241 	bool supports_virtualized_cursor_plane;
242 
243 	/**
244 	 * @master:
245 	 *
246 	 * Master this node is currently associated with. Protected by struct
247 	 * &drm_device.master_mutex, and serialized by @master_lookup_lock.
248 	 *
249 	 * Only relevant if drm_is_primary_client() returns true. Note that
250 	 * this only matches &drm_device.master if the master is the currently
251 	 * active one.
252 	 *
253 	 * To update @master, both &drm_device.master_mutex and
254 	 * @master_lookup_lock need to be held, therefore holding either of
255 	 * them is safe and enough for the read side.
256 	 *
257 	 * When dereferencing this pointer, either hold struct
258 	 * &drm_device.master_mutex for the duration of the pointer's use, or
259 	 * use drm_file_get_master() if struct &drm_device.master_mutex is not
260 	 * currently held and there is no other need to hold it. This prevents
261 	 * @master from being freed during use.
262 	 *
263 	 * See also @authentication and @is_master and the :ref:`section on
264 	 * primary nodes and authentication <drm_primary_node>`.
265 	 */
266 	struct drm_master *master;
267 
268 	/** @master_lookup_lock: Serializes @master. */
269 	spinlock_t master_lookup_lock;
270 
271 	/**
272 	 * @pid: Process that is using this file.
273 	 *
274 	 * Must only be dereferenced under a rcu_read_lock or equivalent.
275 	 *
276 	 * Updates are guarded with dev->filelist_mutex and reference must be
277 	 * dropped after a RCU grace period to accommodate lockless readers.
278 	 */
279 	struct pid __rcu *pid;
280 
281 	/** @client_id: A unique id for fdinfo */
282 	u64 client_id;
283 
284 	/** @magic: Authentication magic, see @authenticated. */
285 	drm_magic_t magic;
286 
287 	/**
288 	 * @lhead:
289 	 *
290 	 * List of all open files of a DRM device, linked into
291 	 * &drm_device.filelist. Protected by &drm_device.filelist_mutex.
292 	 */
293 	struct list_head lhead;
294 
295 	/** @minor: &struct drm_minor for this file. */
296 	struct drm_minor *minor;
297 
298 	/**
299 	 * @object_idr:
300 	 *
301 	 * Mapping of mm object handles to object pointers. Used by the GEM
302 	 * subsystem. Protected by @table_lock.
303 	 */
304 	struct idr object_idr;
305 
306 	/** @table_lock: Protects @object_idr. */
307 	spinlock_t table_lock;
308 
309 	/** @syncobj_idr: Mapping of sync object handles to object pointers. */
310 	struct idr syncobj_idr;
311 	/** @syncobj_table_lock: Protects @syncobj_idr. */
312 	spinlock_t syncobj_table_lock;
313 
314 	/** @filp: Pointer to the core file structure. */
315 	struct file *filp;
316 
317 	/**
318 	 * @driver_priv:
319 	 *
320 	 * Optional pointer for driver private data. Can be allocated in
321 	 * &drm_driver.open and should be freed in &drm_driver.postclose.
322 	 */
323 	void *driver_priv;
324 
325 	/**
326 	 * @fbs:
327 	 *
328 	 * List of &struct drm_framebuffer associated with this file, using the
329 	 * &drm_framebuffer.filp_head entry.
330 	 *
331 	 * Protected by @fbs_lock. Note that the @fbs list holds a reference on
332 	 * the framebuffer object to prevent it from untimely disappearing.
333 	 */
334 	struct list_head fbs;
335 
336 	/** @fbs_lock: Protects @fbs. */
337 	struct mutex fbs_lock;
338 
339 	/**
340 	 * @blobs:
341 	 *
342 	 * User-created blob properties; this retains a reference on the
343 	 * property.
344 	 *
345 	 * Protected by @drm_mode_config.blob_lock;
346 	 */
347 	struct list_head blobs;
348 
349 	/** @event_wait: Waitqueue for new events added to @event_list. */
350 	wait_queue_head_t event_wait;
351 
352 	/**
353 	 * @pending_event_list:
354 	 *
355 	 * List of pending &struct drm_pending_event, used to clean up pending
356 	 * events in case this file gets closed before the event is signalled.
357 	 * Uses the &drm_pending_event.pending_link entry.
358 	 *
359 	 * Protect by &drm_device.event_lock.
360 	 */
361 	struct list_head pending_event_list;
362 
363 	/**
364 	 * @event_list:
365 	 *
366 	 * List of &struct drm_pending_event, ready for delivery to userspace
367 	 * through drm_read(). Uses the &drm_pending_event.link entry.
368 	 *
369 	 * Protect by &drm_device.event_lock.
370 	 */
371 	struct list_head event_list;
372 
373 	/**
374 	 * @event_space:
375 	 *
376 	 * Available event space to prevent userspace from
377 	 * exhausting kernel memory. Currently limited to the fairly arbitrary
378 	 * value of 4KB.
379 	 */
380 	int event_space;
381 
382 	/** @event_read_lock: Serializes drm_read(). */
383 	struct mutex event_read_lock;
384 
385 	/**
386 	 * @prime:
387 	 *
388 	 * Per-file buffer caches used by the PRIME buffer sharing code.
389 	 */
390 	struct drm_prime_file_private prime;
391 };
392 
393 /**
394  * drm_is_primary_client - is this an open file of the primary node
395  * @file_priv: DRM file
396  *
397  * Returns true if this is an open file of the primary node, i.e.
398  * &drm_file.minor of @file_priv is a primary minor.
399  *
400  * See also the :ref:`section on primary nodes and authentication
401  * <drm_primary_node>`.
402  */
drm_is_primary_client(const struct drm_file * file_priv)403 static inline bool drm_is_primary_client(const struct drm_file *file_priv)
404 {
405 	return file_priv->minor->type == DRM_MINOR_PRIMARY;
406 }
407 
408 /**
409  * drm_is_render_client - is this an open file of the render node
410  * @file_priv: DRM file
411  *
412  * Returns true if this is an open file of the render node, i.e.
413  * &drm_file.minor of @file_priv is a render minor.
414  *
415  * See also the :ref:`section on render nodes <drm_render_node>`.
416  */
drm_is_render_client(const struct drm_file * file_priv)417 static inline bool drm_is_render_client(const struct drm_file *file_priv)
418 {
419 	return file_priv->minor->type == DRM_MINOR_RENDER;
420 }
421 
422 /**
423  * drm_is_accel_client - is this an open file of the compute acceleration node
424  * @file_priv: DRM file
425  *
426  * Returns true if this is an open file of the compute acceleration node, i.e.
427  * &drm_file.minor of @file_priv is a accel minor.
428  *
429  * See also :doc:`Introduction to compute accelerators subsystem
430  * </accel/introduction>`.
431  */
drm_is_accel_client(const struct drm_file * file_priv)432 static inline bool drm_is_accel_client(const struct drm_file *file_priv)
433 {
434 	return file_priv->minor->type == DRM_MINOR_ACCEL;
435 }
436 
437 void drm_file_update_pid(struct drm_file *);
438 
439 struct drm_minor *drm_minor_acquire(struct xarray *minors_xa, unsigned int minor_id);
440 void drm_minor_release(struct drm_minor *minor);
441 
442 int drm_open(struct inode *inode, struct file *filp);
443 int drm_open_helper(struct file *filp, struct drm_minor *minor);
444 ssize_t drm_read(struct file *filp, char __user *buffer,
445 		 size_t count, loff_t *offset);
446 int drm_release(struct inode *inode, struct file *filp);
447 int drm_release_noglobal(struct inode *inode, struct file *filp);
448 __poll_t drm_poll(struct file *filp, struct poll_table_struct *wait);
449 int drm_event_reserve_init_locked(struct drm_device *dev,
450 				  struct drm_file *file_priv,
451 				  struct drm_pending_event *p,
452 				  struct drm_event *e);
453 int drm_event_reserve_init(struct drm_device *dev,
454 			   struct drm_file *file_priv,
455 			   struct drm_pending_event *p,
456 			   struct drm_event *e);
457 void drm_event_cancel_free(struct drm_device *dev,
458 			   struct drm_pending_event *p);
459 void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e);
460 void drm_send_event(struct drm_device *dev, struct drm_pending_event *e);
461 void drm_send_event_timestamp_locked(struct drm_device *dev,
462 				     struct drm_pending_event *e,
463 				     ktime_t timestamp);
464 
465 /**
466  * struct drm_memory_stats - GEM object stats associated
467  * @shared: Total size of GEM objects shared between processes
468  * @private: Total size of GEM objects
469  * @resident: Total size of GEM objects backing pages
470  * @purgeable: Total size of GEM objects that can be purged (resident and not active)
471  * @active: Total size of GEM objects active on one or more engines
472  *
473  * Used by drm_print_memory_stats()
474  */
475 struct drm_memory_stats {
476 	u64 shared;
477 	u64 private;
478 	u64 resident;
479 	u64 purgeable;
480 	u64 active;
481 };
482 
483 enum drm_gem_object_status;
484 
485 void drm_print_memory_stats(struct drm_printer *p,
486 			    const struct drm_memory_stats *stats,
487 			    enum drm_gem_object_status supported_status,
488 			    const char *region);
489 
490 void drm_show_memory_stats(struct drm_printer *p, struct drm_file *file);
491 void drm_show_fdinfo(struct seq_file *m, struct file *f);
492 
493 struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags);
494 
495 #endif /* _DRM_FILE_H_ */
496