xref: /openbmc/linux/include/drm/drm_file.h (revision 4da722ca)
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 
36 #include <uapi/drm/drm.h>
37 
38 #include <drm/drm_prime.h>
39 
40 struct dma_fence;
41 struct drm_file;
42 struct drm_device;
43 struct device;
44 
45 /*
46  * FIXME: Not sure we want to have drm_minor here in the end, but to avoid
47  * header include loops we need it here for now.
48  */
49 
50 enum drm_minor_type {
51 	DRM_MINOR_PRIMARY,
52 	DRM_MINOR_CONTROL,
53 	DRM_MINOR_RENDER,
54 };
55 
56 /**
57  * struct drm_minor - DRM device minor structure
58  *
59  * This structure represents a DRM minor number for device nodes in /dev.
60  * Entirely opaque to drivers and should never be inspected directly by drivers.
61  * Drivers instead should only interact with &struct drm_file and of course
62  * &struct drm_device, which is also where driver-private data and resources can
63  * be attached to.
64  */
65 struct drm_minor {
66 	/* private: */
67 	int index;			/* Minor device number */
68 	int type;                       /* Control or render */
69 	struct device *kdev;		/* Linux device */
70 	struct drm_device *dev;
71 
72 	struct dentry *debugfs_root;
73 
74 	struct list_head debugfs_list;
75 	struct mutex debugfs_lock; /* Protects debugfs_list. */
76 };
77 
78 /**
79  * struct drm_pending_event - Event queued up for userspace to read
80  *
81  * This represents a DRM event. Drivers can use this as a generic completion
82  * mechanism, which supports kernel-internal &struct completion, &struct dma_fence
83  * and also the DRM-specific &struct drm_event delivery mechanism.
84  */
85 struct drm_pending_event {
86 	/**
87 	 * @completion:
88 	 *
89 	 * Optional pointer to a kernel internal completion signalled when
90 	 * drm_send_event() is called, useful to internally synchronize with
91 	 * nonblocking operations.
92 	 */
93 	struct completion *completion;
94 
95 	/**
96 	 * @completion_release:
97 	 *
98 	 * Optional callback currently only used by the atomic modeset helpers
99 	 * to clean up the reference count for the structure @completion is
100 	 * stored in.
101 	 */
102 	void (*completion_release)(struct completion *completion);
103 
104 	/**
105 	 * @event:
106 	 *
107 	 * Pointer to the actual event that should be sent to userspace to be
108 	 * read using drm_read(). Can be optional, since nowadays events are
109 	 * also used to signal kernel internal threads with @completion or DMA
110 	 * transactions using @fence.
111 	 */
112 	struct drm_event *event;
113 
114 	/**
115 	 * @fence:
116 	 *
117 	 * Optional DMA fence to unblock other hardware transactions which
118 	 * depend upon the nonblocking DRM operation this event represents.
119 	 */
120 	struct dma_fence *fence;
121 
122 	/**
123 	 * @file_priv:
124 	 *
125 	 * &struct drm_file where @event should be delivered to. Only set when
126 	 * @event is set.
127 	 */
128 	struct drm_file *file_priv;
129 
130 	/**
131 	 * @link:
132 	 *
133 	 * Double-linked list to keep track of this event. Can be used by the
134 	 * driver up to the point when it calls drm_send_event(), after that
135 	 * this list entry is owned by the core for its own book-keeping.
136 	 */
137 	struct list_head link;
138 
139 	/**
140 	 * @pending_link:
141 	 *
142 	 * Entry on &drm_file.pending_event_list, to keep track of all pending
143 	 * events for @file_priv, to allow correct unwinding of them when
144 	 * userspace closes the file before the event is delivered.
145 	 */
146 	struct list_head pending_link;
147 };
148 
149 /**
150  * struct drm_file - DRM file private data
151  *
152  * This structure tracks DRM state per open file descriptor.
153  */
154 struct drm_file {
155 	/**
156 	 * @authenticated:
157 	 *
158 	 * Whether the client is allowed to submit rendering, which for legacy
159 	 * nodes means it must be authenticated.
160 	 *
161 	 * See also the :ref:`section on primary nodes and authentication
162 	 * <drm_primary_node>`.
163 	 */
164 	unsigned authenticated :1;
165 
166 	/**
167 	 * @stereo_allowed:
168 	 *
169 	 * True when the client has asked us to expose stereo 3D mode flags.
170 	 */
171 	unsigned stereo_allowed :1;
172 
173 	/**
174 	 * @universal_planes:
175 	 *
176 	 * True if client understands CRTC primary planes and cursor planes
177 	 * in the plane list. Automatically set when @atomic is set.
178 	 */
179 	unsigned universal_planes:1;
180 
181 	/** @atomic: True if client understands atomic properties. */
182 	unsigned atomic:1;
183 
184 	/**
185 	 * @is_master:
186 	 *
187 	 * This client is the creator of @master. Protected by struct
188 	 * &drm_device.master_mutex.
189 	 *
190 	 * See also the :ref:`section on primary nodes and authentication
191 	 * <drm_primary_node>`.
192 	 */
193 	unsigned is_master:1;
194 
195 	/**
196 	 * @master:
197 	 *
198 	 * Master this node is currently associated with. Only relevant if
199 	 * drm_is_primary_client() returns true. Note that this only
200 	 * matches &drm_device.master if the master is the currently active one.
201 	 *
202 	 * See also @authentication and @is_master and the :ref:`section on
203 	 * primary nodes and authentication <drm_primary_node>`.
204 	 */
205 	struct drm_master *master;
206 
207 	/** @pid: Process that opened this file. */
208 	struct pid *pid;
209 
210 	/** @magic: Authentication magic, see @authenticated. */
211 	drm_magic_t magic;
212 
213 	/**
214 	 * @lhead:
215 	 *
216 	 * List of all open files of a DRM device, linked into
217 	 * &drm_device.filelist. Protected by &drm_device.filelist_mutex.
218 	 */
219 	struct list_head lhead;
220 
221 	/** @minor: &struct drm_minor for this file. */
222 	struct drm_minor *minor;
223 
224 	/**
225 	 * @object_idr:
226 	 *
227 	 * Mapping of mm object handles to object pointers. Used by the GEM
228 	 * subsystem. Protected by @table_lock.
229 	 */
230 	struct idr object_idr;
231 
232 	/** @table_lock: Protects @object_idr. */
233 	spinlock_t table_lock;
234 
235 	/** @syncobj_idr: Mapping of sync object handles to object pointers. */
236 	struct idr syncobj_idr;
237 	/** @syncobj_table_lock: Protects @syncobj_idr. */
238 	spinlock_t syncobj_table_lock;
239 
240 	/** @filp: Pointer to the core file structure. */
241 	struct file *filp;
242 
243 	/**
244 	 * @driver_priv:
245 	 *
246 	 * Optional pointer for driver private data. Can be allocated in
247 	 * &drm_driver.open and should be freed in &drm_driver.postclose.
248 	 */
249 	void *driver_priv;
250 
251 	/**
252 	 * @fbs:
253 	 *
254 	 * List of &struct drm_framebuffer associated with this file, using the
255 	 * &drm_framebuffer.filp_head entry.
256 	 *
257 	 * Protected by @fbs_lock. Note that the @fbs list holds a reference on
258 	 * the framebuffer object to prevent it from untimely disappearing.
259 	 */
260 	struct list_head fbs;
261 
262 	/** @fbs_lock: Protects @fbs. */
263 	struct mutex fbs_lock;
264 
265 	/**
266 	 * @blobs:
267 	 *
268 	 * User-created blob properties; this retains a reference on the
269 	 * property.
270 	 *
271 	 * Protected by @drm_mode_config.blob_lock;
272 	 */
273 	struct list_head blobs;
274 
275 	/** @event_wait: Waitqueue for new events added to @event_list. */
276 	wait_queue_head_t event_wait;
277 
278 	/**
279 	 * @pending_event_list:
280 	 *
281 	 * List of pending &struct drm_pending_event, used to clean up pending
282 	 * events in case this file gets closed before the event is signalled.
283 	 * Uses the &drm_pending_event.pending_link entry.
284 	 *
285 	 * Protect by &drm_device.event_lock.
286 	 */
287 	struct list_head pending_event_list;
288 
289 	/**
290 	 * @event_list:
291 	 *
292 	 * List of &struct drm_pending_event, ready for delivery to userspace
293 	 * through drm_read(). Uses the &drm_pending_event.link entry.
294 	 *
295 	 * Protect by &drm_device.event_lock.
296 	 */
297 	struct list_head event_list;
298 
299 	/**
300 	 * @event_space:
301 	 *
302 	 * Available event space to prevent userspace from
303 	 * exhausting kernel memory. Currently limited to the fairly arbitrary
304 	 * value of 4KB.
305 	 */
306 	int event_space;
307 
308 	/** @event_read_lock: Serializes drm_read(). */
309 	struct mutex event_read_lock;
310 
311 	/**
312 	 * @prime:
313 	 *
314 	 * Per-file buffer caches used by the PRIME buffer sharing code.
315 	 */
316 	struct drm_prime_file_private prime;
317 
318 	/* private: */
319 	unsigned long lock_count; /* DRI1 legacy lock count */
320 };
321 
322 /**
323  * drm_is_primary_client - is this an open file of the primary node
324  * @file_priv: DRM file
325  *
326  * Returns true if this is an open file of the primary node, i.e.
327  * &drm_file.minor of @file_priv is a primary minor.
328  *
329  * See also the :ref:`section on primary nodes and authentication
330  * <drm_primary_node>`.
331  */
332 static inline bool drm_is_primary_client(const struct drm_file *file_priv)
333 {
334 	return file_priv->minor->type == DRM_MINOR_PRIMARY;
335 }
336 
337 /**
338  * drm_is_render_client - is this an open file of the render node
339  * @file_priv: DRM file
340  *
341  * Returns true if this is an open file of the render node, i.e.
342  * &drm_file.minor of @file_priv is a render minor.
343  *
344  * See also the :ref:`section on render nodes <drm_render_node>`.
345  */
346 static inline bool drm_is_render_client(const struct drm_file *file_priv)
347 {
348 	return file_priv->minor->type == DRM_MINOR_RENDER;
349 }
350 
351 /**
352  * drm_is_control_client - is this an open file of the control node
353  * @file_priv: DRM file
354  *
355  * Control nodes are deprecated and in the process of getting removed from the
356  * DRM userspace API. Do not ever use!
357  */
358 static inline bool drm_is_control_client(const struct drm_file *file_priv)
359 {
360 	return file_priv->minor->type == DRM_MINOR_CONTROL;
361 }
362 
363 int drm_open(struct inode *inode, struct file *filp);
364 ssize_t drm_read(struct file *filp, char __user *buffer,
365 		 size_t count, loff_t *offset);
366 int drm_release(struct inode *inode, struct file *filp);
367 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait);
368 int drm_event_reserve_init_locked(struct drm_device *dev,
369 				  struct drm_file *file_priv,
370 				  struct drm_pending_event *p,
371 				  struct drm_event *e);
372 int drm_event_reserve_init(struct drm_device *dev,
373 			   struct drm_file *file_priv,
374 			   struct drm_pending_event *p,
375 			   struct drm_event *e);
376 void drm_event_cancel_free(struct drm_device *dev,
377 			   struct drm_pending_event *p);
378 void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e);
379 void drm_send_event(struct drm_device *dev, struct drm_pending_event *e);
380 
381 #endif /* _DRM_FILE_H_ */
382