include/drm/drm_file.h

   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 device;
  45 struct file;
  46
  47 /*
  48  * FIXME: Not sure we want to have drm_minor here in the end, but to avoid
  49  * header include loops we need it here for now.
  50  */
  51
  52 /* Note that the order of this enum is ABI (it determines
  53  * /dev/dri/renderD* numbers).
  54  */
  55 enum drm_minor_type {
  56         DRM_MINOR_PRIMARY,
  57         DRM_MINOR_CONTROL,
  58         DRM_MINOR_RENDER,
  59 };
  60
  61 /**
  62  * struct drm_minor - DRM device minor structure
  63  *
  64  * This structure represents a DRM minor number for device nodes in /dev.
  65  * Entirely opaque to drivers and should never be inspected directly by drivers.
  66  * Drivers instead should only interact with &struct drm_file and of course
  67  * &struct drm_device, which is also where driver-private data and resources can
  68  * be attached to.
  69  */
  70 struct drm_minor {
  71         /* private: */
  72         int index;                      /* Minor device number */
  73         int type;                       /* Control or render */
  74         struct device *kdev;            /* Linux device */
  75         struct drm_device *dev;
  76
  77         struct dentry *debugfs_root;
  78
  79         struct list_head debugfs_list;
  80         struct mutex debugfs_lock; /* Protects debugfs_list. */
  81 };
  82
  83 /**
  84  * struct drm_pending_event - Event queued up for userspace to read
  85  *
  86  * This represents a DRM event. Drivers can use this as a generic completion
  87  * mechanism, which supports kernel-internal &struct completion, &struct dma_fence
  88  * and also the DRM-specific &struct drm_event delivery mechanism.
  89  */
  90 struct drm_pending_event {
  91         /**
  92          * @completion:
  93          *
  94          * Optional pointer to a kernel internal completion signalled when
  95          * drm_send_event() is called, useful to internally synchronize with
  96          * nonblocking operations.
  97          */
  98         struct completion *completion;
  99
 100         /**
 101          * @completion_release:
 102          *
 103          * Optional callback currently only used by the atomic modeset helpers
 104          * to clean up the reference count for the structure @completion is
 105          * stored in.
 106          */
 107         void (*completion_release)(struct completion *completion);
 108
 109         /**
 110          * @event:
 111          *
 112          * Pointer to the actual event that should be sent to userspace to be
 113          * read using drm_read(). Can be optional, since nowadays events are
 114          * also used to signal kernel internal threads with @completion or DMA
 115          * transactions using @fence.
 116          */
 117         struct drm_event *event;
 118
 119         /**
 120          * @fence:
 121          *
 122          * Optional DMA fence to unblock other hardware transactions which
 123          * depend upon the nonblocking DRM operation this event represents.
 124          */
 125         struct dma_fence *fence;
 126
 127         /**
 128          * @file_priv:
 129          *
 130          * &struct drm_file where @event should be delivered to. Only set when
 131          * @event is set.
 132          */
 133         struct drm_file *file_priv;
 134
 135         /**
 136          * @link:
 137          *
 138          * Double-linked list to keep track of this event. Can be used by the
 139          * driver up to the point when it calls drm_send_event(), after that
 140          * this list entry is owned by the core for its own book-keeping.
 141          */
 142         struct list_head link;
 143
 144         /**
 145          * @pending_link:
 146          *
 147          * Entry on &drm_file.pending_event_list, to keep track of all pending
 148          * events for @file_priv, to allow correct unwinding of them when
 149          * userspace closes the file before the event is delivered.
 150          */
 151         struct list_head pending_link;
 152 };
 153
 154 /**
 155  * struct drm_file - DRM file private data
 156  *
 157  * This structure tracks DRM state per open file descriptor.
 158  */
 159 struct drm_file {
 160         /**
 161          * @authenticated:
 162          *
 163          * Whether the client is allowed to submit rendering, which for legacy
 164          * nodes means it must be authenticated.
 165          *
 166          * See also the :ref:`section on primary nodes and authentication
 167          * <drm_primary_node>`.
 168          */
 169         bool authenticated;
 170
 171         /**
 172          * @stereo_allowed:
 173          *
 174          * True when the client has asked us to expose stereo 3D mode flags.
 175          */
 176         bool stereo_allowed;
 177
 178         /**
 179          * @universal_planes:
 180          *
 181          * True if client understands CRTC primary planes and cursor planes
 182          * in the plane list. Automatically set when @atomic is set.
 183          */
 184         bool universal_planes;
 185
 186         /** @atomic: True if client understands atomic properties. */
 187         bool atomic;
 188
 189         /**
 190          * @aspect_ratio_allowed:
 191          *
 192          * True, if client can handle picture aspect ratios, and has requested
 193          * to pass this information along with the mode.
 194          */
 195         bool aspect_ratio_allowed;
 196
 197         /**
 198          * @writeback_connectors:
 199          *
 200          * True if client understands writeback connectors
 201          */
 202         bool writeback_connectors;
 203
 204         /**
 205          * @was_master:
 206          *
 207          * This client has or had, master capability. Protected by struct
 208          * &drm_device.master_mutex.
 209          *
 210          * This is used to ensure that CAP_SYS_ADMIN is not enforced, if the
 211          * client is or was master in the past.
 212          */
 213         bool was_master;
 214
 215         /**
 216          * @is_master:
 217          *
 218          * This client is the creator of @master. Protected by struct
 219          * &drm_device.master_mutex.
 220          *
 221          * See also the :ref:`section on primary nodes and authentication
 222          * <drm_primary_node>`.
 223          */
 224         bool is_master;
 225
 226         /**
 227          * @master:
 228          *
 229          * Master this node is currently associated with. Protected by struct
 230          * &drm_device.master_mutex, and serialized by @master_lookup_lock.
 231          *
 232          * Only relevant if drm_is_primary_client() returns true. Note that
 233          * this only matches &drm_device.master if the master is the currently
 234          * active one.
 235          *
 236          * To update @master, both &drm_device.master_mutex and
 237          * @master_lookup_lock need to be held, therefore holding either of
 238          * them is safe and enough for the read side.
 239          *
 240          * When dereferencing this pointer, either hold struct
 241          * &drm_device.master_mutex for the duration of the pointer's use, or
 242          * use drm_file_get_master() if struct &drm_device.master_mutex is not
 243          * currently held and there is no other need to hold it. This prevents
 244          * @master from being freed during use.
 245          *
 246          * See also @authentication and @is_master and the :ref:`section on
 247          * primary nodes and authentication <drm_primary_node>`.
 248          */
 249         struct drm_master *master;
 250
 251         /** @master_lock: Serializes @master. */
 252         spinlock_t master_lookup_lock;
 253
 254         /** @pid: Process that opened this file. */
 255         struct pid *pid;
 256
 257         /** @magic: Authentication magic, see @authenticated. */
 258         drm_magic_t magic;
 259
 260         /**
 261          * @lhead:
 262          *
 263          * List of all open files of a DRM device, linked into
 264          * &drm_device.filelist. Protected by &drm_device.filelist_mutex.
 265          */
 266         struct list_head lhead;
 267
 268         /** @minor: &struct drm_minor for this file. */
 269         struct drm_minor *minor;
 270
 271         /**
 272          * @object_idr:
 273          *
 274          * Mapping of mm object handles to object pointers. Used by the GEM
 275          * subsystem. Protected by @table_lock.
 276          */
 277         struct idr object_idr;
 278
 279         /** @table_lock: Protects @object_idr. */
 280         spinlock_t table_lock;
 281
 282         /** @syncobj_idr: Mapping of sync object handles to object pointers. */
 283         struct idr syncobj_idr;
 284         /** @syncobj_table_lock: Protects @syncobj_idr. */
 285         spinlock_t syncobj_table_lock;
 286
 287         /** @filp: Pointer to the core file structure. */
 288         struct file *filp;
 289
 290         /**
 291          * @driver_priv:
 292          *
 293          * Optional pointer for driver private data. Can be allocated in
 294          * &drm_driver.open and should be freed in &drm_driver.postclose.
 295          */
 296         void *driver_priv;
 297
 298         /**
 299          * @fbs:
 300          *
 301          * List of &struct drm_framebuffer associated with this file, using the
 302          * &drm_framebuffer.filp_head entry.
 303          *
 304          * Protected by @fbs_lock. Note that the @fbs list holds a reference on
 305          * the framebuffer object to prevent it from untimely disappearing.
 306          */
 307         struct list_head fbs;
 308
 309         /** @fbs_lock: Protects @fbs. */
 310         struct mutex fbs_lock;
 311
 312         /**
 313          * @blobs:
 314          *
 315          * User-created blob properties; this retains a reference on the
 316          * property.
 317          *
 318          * Protected by @drm_mode_config.blob_lock;
 319          */
 320         struct list_head blobs;
 321
 322         /** @event_wait: Waitqueue for new events added to @event_list. */
 323         wait_queue_head_t event_wait;
 324
 325         /**
 326          * @pending_event_list:
 327          *
 328          * List of pending &struct drm_pending_event, used to clean up pending
 329          * events in case this file gets closed before the event is signalled.
 330          * Uses the &drm_pending_event.pending_link entry.
 331          *
 332          * Protect by &drm_device.event_lock.
 333          */
 334         struct list_head pending_event_list;
 335
 336         /**
 337          * @event_list:
 338          *
 339          * List of &struct drm_pending_event, ready for delivery to userspace
 340          * through drm_read(). Uses the &drm_pending_event.link entry.
 341          *
 342          * Protect by &drm_device.event_lock.
 343          */
 344         struct list_head event_list;
 345
 346         /**
 347          * @event_space:
 348          *
 349          * Available event space to prevent userspace from
 350          * exhausting kernel memory. Currently limited to the fairly arbitrary
 351          * value of 4KB.
 352          */
 353         int event_space;
 354
 355         /** @event_read_lock: Serializes drm_read(). */
 356         struct mutex event_read_lock;
 357
 358         /**
 359          * @prime:
 360          *
 361          * Per-file buffer caches used by the PRIME buffer sharing code.
 362          */
 363         struct drm_prime_file_private prime;
 364
 365         /* private: */
 366 #if IS_ENABLED(CONFIG_DRM_LEGACY)
 367         unsigned long lock_count; /* DRI1 legacy lock count */
 368 #endif
 369 };
 370
 371 /**
 372  * drm_is_primary_client - is this an open file of the primary node
 373  * @file_priv: DRM file
 374  *
 375  * Returns true if this is an open file of the primary node, i.e.
 376  * &drm_file.minor of @file_priv is a primary minor.
 377  *
 378  * See also the :ref:`section on primary nodes and authentication
 379  * <drm_primary_node>`.
 380  */
 381 static inline bool drm_is_primary_client(const struct drm_file *file_priv)
 382 {
 383         return file_priv->minor->type == DRM_MINOR_PRIMARY;
 384 }
 385
 386 /**
 387  * drm_is_render_client - is this an open file of the render node
 388  * @file_priv: DRM file
 389  *
 390  * Returns true if this is an open file of the render node, i.e.
 391  * &drm_file.minor of @file_priv is a render minor.
 392  *
 393  * See also the :ref:`section on render nodes <drm_render_node>`.
 394  */
 395 static inline bool drm_is_render_client(const struct drm_file *file_priv)
 396 {
 397         return file_priv->minor->type == DRM_MINOR_RENDER;
 398 }
 399
 400 int drm_open(struct inode *inode, struct file *filp);
 401 ssize_t drm_read(struct file *filp, char __user *buffer,
 402                  size_t count, loff_t *offset);
 403 int drm_release(struct inode *inode, struct file *filp);
 404 int drm_release_noglobal(struct inode *inode, struct file *filp);
 405 __poll_t drm_poll(struct file *filp, struct poll_table_struct *wait);
 406 int drm_event_reserve_init_locked(struct drm_device *dev,
 407                                   struct drm_file *file_priv,
 408                                   struct drm_pending_event *p,
 409                                   struct drm_event *e);
 410 int drm_event_reserve_init(struct drm_device *dev,
 411                            struct drm_file *file_priv,
 412                            struct drm_pending_event *p,
 413                            struct drm_event *e);
 414 void drm_event_cancel_free(struct drm_device *dev,
 415                            struct drm_pending_event *p);
 416 void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e);
 417 void drm_send_event(struct drm_device *dev, struct drm_pending_event *e);
 418 void drm_send_event_timestamp_locked(struct drm_device *dev,
 419                                      struct drm_pending_event *e,
 420                                      ktime_t timestamp);
 421
 422 struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags);
 423
 424 #ifdef CONFIG_MMU
 425 struct drm_vma_offset_manager;
 426 unsigned long drm_get_unmapped_area(struct file *file,
 427                                     unsigned long uaddr, unsigned long len,
 428                                     unsigned long pgoff, unsigned long flags,
 429                                     struct drm_vma_offset_manager *mgr);
 430 #endif /* CONFIG_MMU */
 431
 432
 433 #endif /* _DRM_FILE_H_ */