Line data Source code
1 : /*
2 : * \author Rickard E. (Rik) Faith <faith@valinux.com>
3 : * \author Daryll Strauss <daryll@valinux.com>
4 : * \author Gareth Hughes <gareth@valinux.com>
5 : */
6 :
7 : /*
8 : * Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com
9 : *
10 : * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
11 : * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
12 : * All Rights Reserved.
13 : *
14 : * Permission is hereby granted, free of charge, to any person obtaining a
15 : * copy of this software and associated documentation files (the "Software"),
16 : * to deal in the Software without restriction, including without limitation
17 : * the rights to use, copy, modify, merge, publish, distribute, sublicense,
18 : * and/or sell copies of the Software, and to permit persons to whom the
19 : * Software is furnished to do so, subject to the following conditions:
20 : *
21 : * The above copyright notice and this permission notice (including the next
22 : * paragraph) shall be included in all copies or substantial portions of the
23 : * Software.
24 : *
25 : * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
26 : * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
27 : * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
28 : * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
29 : * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
30 : * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
31 : * OTHER DEALINGS IN THE SOFTWARE.
32 : */
33 :
34 : #include <linux/anon_inodes.h>
35 : #include <linux/dma-fence.h>
36 : #include <linux/file.h>
37 : #include <linux/module.h>
38 : #include <linux/pci.h>
39 : #include <linux/poll.h>
40 : #include <linux/slab.h>
41 :
42 : #include <drm/drm_client.h>
43 : #include <drm/drm_drv.h>
44 : #include <drm/drm_file.h>
45 : #include <drm/drm_print.h>
46 :
47 : #include "drm_crtc_internal.h"
48 : #include "drm_internal.h"
49 : #include "drm_legacy.h"
50 :
51 : /* from BKL pushdown */
52 : DEFINE_MUTEX(drm_global_mutex);
53 :
54 2 : bool drm_dev_needs_global_mutex(struct drm_device *dev)
55 : {
56 : /*
57 : * Legacy drivers rely on all kinds of BKL locking semantics, don't
58 : * bother. They also still need BKL locking for their ioctls, so better
59 : * safe than sorry.
60 : */
61 2 : if (drm_core_check_feature(dev, DRIVER_LEGACY))
62 : return true;
63 :
64 : /*
65 : * The deprecated ->load callback must be called after the driver is
66 : * already registered. This means such drivers rely on the BKL to make
67 : * sure an open can't proceed until the driver is actually fully set up.
68 : * Similar hilarity holds for the unload callback.
69 : */
70 2 : if (dev->driver->load || dev->driver->unload)
71 : return true;
72 :
73 : /*
74 : * Drivers with the lastclose callback assume that it's synchronized
75 : * against concurrent opens, which again needs the BKL. The proper fix
76 : * is to use the drm_client infrastructure with proper locking for each
77 : * client.
78 : */
79 2 : if (dev->driver->lastclose)
80 : return true;
81 :
82 2 : return false;
83 : }
84 :
85 : /**
86 : * DOC: file operations
87 : *
88 : * Drivers must define the file operations structure that forms the DRM
89 : * userspace API entry point, even though most of those operations are
90 : * implemented in the DRM core. The resulting &struct file_operations must be
91 : * stored in the &drm_driver.fops field. The mandatory functions are drm_open(),
92 : * drm_read(), drm_ioctl() and drm_compat_ioctl() if CONFIG_COMPAT is enabled
93 : * Note that drm_compat_ioctl will be NULL if CONFIG_COMPAT=n, so there's no
94 : * need to sprinkle #ifdef into the code. Drivers which implement private ioctls
95 : * that require 32/64 bit compatibility support must provide their own
96 : * &file_operations.compat_ioctl handler that processes private ioctls and calls
97 : * drm_compat_ioctl() for core ioctls.
98 : *
99 : * In addition drm_read() and drm_poll() provide support for DRM events. DRM
100 : * events are a generic and extensible means to send asynchronous events to
101 : * userspace through the file descriptor. They are used to send vblank event and
102 : * page flip completions by the KMS API. But drivers can also use it for their
103 : * own needs, e.g. to signal completion of rendering.
104 : *
105 : * For the driver-side event interface see drm_event_reserve_init() and
106 : * drm_send_event() as the main starting points.
107 : *
108 : * The memory mapping implementation will vary depending on how the driver
109 : * manages memory. Legacy drivers will use the deprecated drm_legacy_mmap()
110 : * function, modern drivers should use one of the provided memory-manager
111 : * specific implementations. For GEM-based drivers this is drm_gem_mmap().
112 : *
113 : * No other file operations are supported by the DRM userspace API. Overall the
114 : * following is an example &file_operations structure::
115 : *
116 : * static const example_drm_fops = {
117 : * .owner = THIS_MODULE,
118 : * .open = drm_open,
119 : * .release = drm_release,
120 : * .unlocked_ioctl = drm_ioctl,
121 : * .compat_ioctl = drm_compat_ioctl, // NULL if CONFIG_COMPAT=n
122 : * .poll = drm_poll,
123 : * .read = drm_read,
124 : * .llseek = no_llseek,
125 : * .mmap = drm_gem_mmap,
126 : * };
127 : *
128 : * For plain GEM based drivers there is the DEFINE_DRM_GEM_FOPS() macro, and for
129 : * DMA based drivers there is the DEFINE_DRM_GEM_DMA_FOPS() macro to make this
130 : * simpler.
131 : *
132 : * The driver's &file_operations must be stored in &drm_driver.fops.
133 : *
134 : * For driver-private IOCTL handling see the more detailed discussion in
135 : * :ref:`IOCTL support in the userland interfaces chapter<drm_driver_ioctl>`.
136 : */
137 :
138 : /**
139 : * drm_file_alloc - allocate file context
140 : * @minor: minor to allocate on
141 : *
142 : * This allocates a new DRM file context. It is not linked into any context and
143 : * can be used by the caller freely. Note that the context keeps a pointer to
144 : * @minor, so it must be freed before @minor is.
145 : *
146 : * RETURNS:
147 : * Pointer to newly allocated context, ERR_PTR on failure.
148 : */
149 0 : struct drm_file *drm_file_alloc(struct drm_minor *minor)
150 : {
151 0 : struct drm_device *dev = minor->dev;
152 : struct drm_file *file;
153 : int ret;
154 :
155 0 : file = kzalloc(sizeof(*file), GFP_KERNEL);
156 0 : if (!file)
157 : return ERR_PTR(-ENOMEM);
158 :
159 0 : file->pid = get_pid(task_tgid(current));
160 0 : file->minor = minor;
161 :
162 : /* for compatibility root is always authenticated */
163 0 : file->authenticated = capable(CAP_SYS_ADMIN);
164 :
165 0 : INIT_LIST_HEAD(&file->lhead);
166 0 : INIT_LIST_HEAD(&file->fbs);
167 0 : mutex_init(&file->fbs_lock);
168 0 : INIT_LIST_HEAD(&file->blobs);
169 0 : INIT_LIST_HEAD(&file->pending_event_list);
170 0 : INIT_LIST_HEAD(&file->event_list);
171 0 : init_waitqueue_head(&file->event_wait);
172 0 : file->event_space = 4096; /* set aside 4k for event buffer */
173 :
174 0 : spin_lock_init(&file->master_lookup_lock);
175 0 : mutex_init(&file->event_read_lock);
176 :
177 0 : if (drm_core_check_feature(dev, DRIVER_GEM))
178 0 : drm_gem_open(dev, file);
179 :
180 0 : if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
181 0 : drm_syncobj_open(file);
182 :
183 0 : drm_prime_init_file_private(&file->prime);
184 :
185 0 : if (dev->driver->open) {
186 0 : ret = dev->driver->open(dev, file);
187 0 : if (ret < 0)
188 : goto out_prime_destroy;
189 : }
190 :
191 : return file;
192 :
193 : out_prime_destroy:
194 0 : drm_prime_destroy_file_private(&file->prime);
195 0 : if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
196 0 : drm_syncobj_release(file);
197 0 : if (drm_core_check_feature(dev, DRIVER_GEM))
198 0 : drm_gem_release(dev, file);
199 0 : put_pid(file->pid);
200 0 : kfree(file);
201 :
202 0 : return ERR_PTR(ret);
203 : }
204 :
205 0 : static void drm_events_release(struct drm_file *file_priv)
206 : {
207 0 : struct drm_device *dev = file_priv->minor->dev;
208 : struct drm_pending_event *e, *et;
209 : unsigned long flags;
210 :
211 0 : spin_lock_irqsave(&dev->event_lock, flags);
212 :
213 : /* Unlink pending events */
214 0 : list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
215 : pending_link) {
216 0 : list_del(&e->pending_link);
217 0 : e->file_priv = NULL;
218 : }
219 :
220 : /* Remove unconsumed events */
221 0 : list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
222 0 : list_del(&e->link);
223 0 : kfree(e);
224 : }
225 :
226 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
227 0 : }
228 :
229 : /**
230 : * drm_file_free - free file context
231 : * @file: context to free, or NULL
232 : *
233 : * This destroys and deallocates a DRM file context previously allocated via
234 : * drm_file_alloc(). The caller must make sure to unlink it from any contexts
235 : * before calling this.
236 : *
237 : * If NULL is passed, this is a no-op.
238 : */
239 0 : void drm_file_free(struct drm_file *file)
240 : {
241 : struct drm_device *dev;
242 :
243 0 : if (!file)
244 : return;
245 :
246 0 : dev = file->minor->dev;
247 :
248 0 : drm_dbg_core(dev, "comm=\"%s\", pid=%d, dev=0x%lx, open_count=%d\n",
249 : current->comm, task_pid_nr(current),
250 : (long)old_encode_dev(file->minor->kdev->devt),
251 : atomic_read(&dev->open_count));
252 :
253 : #ifdef CONFIG_DRM_LEGACY
254 : if (drm_core_check_feature(dev, DRIVER_LEGACY) &&
255 : dev->driver->preclose)
256 : dev->driver->preclose(dev, file);
257 : #endif
258 :
259 0 : if (drm_core_check_feature(dev, DRIVER_LEGACY))
260 : drm_legacy_lock_release(dev, file->filp);
261 :
262 0 : if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
263 : drm_legacy_reclaim_buffers(dev, file);
264 :
265 0 : drm_events_release(file);
266 :
267 0 : if (drm_core_check_feature(dev, DRIVER_MODESET)) {
268 0 : drm_fb_release(file);
269 0 : drm_property_destroy_user_blobs(dev, file);
270 : }
271 :
272 0 : if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
273 0 : drm_syncobj_release(file);
274 :
275 0 : if (drm_core_check_feature(dev, DRIVER_GEM))
276 0 : drm_gem_release(dev, file);
277 :
278 0 : drm_legacy_ctxbitmap_flush(dev, file);
279 :
280 0 : if (drm_is_primary_client(file))
281 0 : drm_master_release(file);
282 :
283 0 : if (dev->driver->postclose)
284 0 : dev->driver->postclose(dev, file);
285 :
286 0 : drm_prime_destroy_file_private(&file->prime);
287 :
288 0 : WARN_ON(!list_empty(&file->event_list));
289 :
290 0 : put_pid(file->pid);
291 0 : kfree(file);
292 : }
293 :
294 0 : static void drm_close_helper(struct file *filp)
295 : {
296 0 : struct drm_file *file_priv = filp->private_data;
297 0 : struct drm_device *dev = file_priv->minor->dev;
298 :
299 0 : mutex_lock(&dev->filelist_mutex);
300 0 : list_del(&file_priv->lhead);
301 0 : mutex_unlock(&dev->filelist_mutex);
302 :
303 0 : drm_file_free(file_priv);
304 0 : }
305 :
306 : /*
307 : * Check whether DRI will run on this CPU.
308 : *
309 : * \return non-zero if the DRI will run on this CPU, or zero otherwise.
310 : */
311 : static int drm_cpu_valid(void)
312 : {
313 : #if defined(__sparc__) && !defined(__sparc_v9__)
314 : return 0; /* No cmpxchg before v9 sparc. */
315 : #endif
316 : return 1;
317 : }
318 :
319 : /*
320 : * Called whenever a process opens a drm node
321 : *
322 : * \param filp file pointer.
323 : * \param minor acquired minor-object.
324 : * \return zero on success or a negative number on failure.
325 : *
326 : * Creates and initializes a drm_file structure for the file private data in \p
327 : * filp and add it into the double linked list in \p dev.
328 : */
329 0 : int drm_open_helper(struct file *filp, struct drm_minor *minor)
330 : {
331 0 : struct drm_device *dev = minor->dev;
332 : struct drm_file *priv;
333 : int ret;
334 :
335 0 : if (filp->f_flags & O_EXCL)
336 : return -EBUSY; /* No exclusive opens */
337 : if (!drm_cpu_valid())
338 : return -EINVAL;
339 0 : if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
340 : dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
341 : return -EINVAL;
342 :
343 0 : drm_dbg_core(dev, "comm=\"%s\", pid=%d, minor=%d\n",
344 : current->comm, task_pid_nr(current), minor->index);
345 :
346 0 : priv = drm_file_alloc(minor);
347 0 : if (IS_ERR(priv))
348 0 : return PTR_ERR(priv);
349 :
350 0 : if (drm_is_primary_client(priv)) {
351 0 : ret = drm_master_open(priv);
352 0 : if (ret) {
353 0 : drm_file_free(priv);
354 0 : return ret;
355 : }
356 : }
357 :
358 0 : filp->private_data = priv;
359 0 : filp->f_mode |= FMODE_UNSIGNED_OFFSET;
360 0 : priv->filp = filp;
361 :
362 0 : mutex_lock(&dev->filelist_mutex);
363 0 : list_add(&priv->lhead, &dev->filelist);
364 0 : mutex_unlock(&dev->filelist_mutex);
365 :
366 : #ifdef CONFIG_DRM_LEGACY
367 : #ifdef __alpha__
368 : /*
369 : * Default the hose
370 : */
371 : if (!dev->hose) {
372 : struct pci_dev *pci_dev;
373 :
374 : pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
375 : if (pci_dev) {
376 : dev->hose = pci_dev->sysdata;
377 : pci_dev_put(pci_dev);
378 : }
379 : if (!dev->hose) {
380 : struct pci_bus *b = list_entry(pci_root_buses.next,
381 : struct pci_bus, node);
382 : if (b)
383 : dev->hose = b->sysdata;
384 : }
385 : }
386 : #endif
387 : #endif
388 :
389 0 : return 0;
390 : }
391 :
392 : /**
393 : * drm_open - open method for DRM file
394 : * @inode: device inode
395 : * @filp: file pointer.
396 : *
397 : * This function must be used by drivers as their &file_operations.open method.
398 : * It looks up the correct DRM device and instantiates all the per-file
399 : * resources for it. It also calls the &drm_driver.open driver callback.
400 : *
401 : * RETURNS:
402 : *
403 : * 0 on success or negative errno value on failure.
404 : */
405 0 : int drm_open(struct inode *inode, struct file *filp)
406 : {
407 : struct drm_device *dev;
408 : struct drm_minor *minor;
409 : int retcode;
410 0 : int need_setup = 0;
411 :
412 0 : minor = drm_minor_acquire(iminor(inode));
413 0 : if (IS_ERR(minor))
414 0 : return PTR_ERR(minor);
415 :
416 0 : dev = minor->dev;
417 0 : if (drm_dev_needs_global_mutex(dev))
418 0 : mutex_lock(&drm_global_mutex);
419 :
420 0 : if (!atomic_fetch_inc(&dev->open_count))
421 : need_setup = 1;
422 :
423 : /* share address_space across all char-devs of a single device */
424 0 : filp->f_mapping = dev->anon_inode->i_mapping;
425 :
426 0 : retcode = drm_open_helper(filp, minor);
427 0 : if (retcode)
428 : goto err_undo;
429 : if (need_setup) {
430 : retcode = drm_legacy_setup(dev);
431 : if (retcode) {
432 : drm_close_helper(filp);
433 : goto err_undo;
434 : }
435 : }
436 :
437 0 : if (drm_dev_needs_global_mutex(dev))
438 0 : mutex_unlock(&drm_global_mutex);
439 :
440 : return 0;
441 :
442 : err_undo:
443 0 : atomic_dec(&dev->open_count);
444 0 : if (drm_dev_needs_global_mutex(dev))
445 0 : mutex_unlock(&drm_global_mutex);
446 0 : drm_minor_release(minor);
447 0 : return retcode;
448 : }
449 : EXPORT_SYMBOL(drm_open);
450 :
451 0 : void drm_lastclose(struct drm_device * dev)
452 : {
453 0 : drm_dbg_core(dev, "\n");
454 :
455 0 : if (dev->driver->lastclose)
456 0 : dev->driver->lastclose(dev);
457 0 : drm_dbg_core(dev, "driver lastclose completed\n");
458 :
459 0 : if (drm_core_check_feature(dev, DRIVER_LEGACY))
460 : drm_legacy_dev_reinit(dev);
461 :
462 0 : drm_client_dev_restore(dev);
463 0 : }
464 :
465 : /**
466 : * drm_release - release method for DRM file
467 : * @inode: device inode
468 : * @filp: file pointer.
469 : *
470 : * This function must be used by drivers as their &file_operations.release
471 : * method. It frees any resources associated with the open file, and calls the
472 : * &drm_driver.postclose driver callback. If this is the last open file for the
473 : * DRM device also proceeds to call the &drm_driver.lastclose driver callback.
474 : *
475 : * RETURNS:
476 : *
477 : * Always succeeds and returns 0.
478 : */
479 0 : int drm_release(struct inode *inode, struct file *filp)
480 : {
481 0 : struct drm_file *file_priv = filp->private_data;
482 0 : struct drm_minor *minor = file_priv->minor;
483 0 : struct drm_device *dev = minor->dev;
484 :
485 0 : if (drm_dev_needs_global_mutex(dev))
486 0 : mutex_lock(&drm_global_mutex);
487 :
488 0 : drm_dbg_core(dev, "open_count = %d\n", atomic_read(&dev->open_count));
489 :
490 0 : drm_close_helper(filp);
491 :
492 0 : if (atomic_dec_and_test(&dev->open_count))
493 0 : drm_lastclose(dev);
494 :
495 0 : if (drm_dev_needs_global_mutex(dev))
496 0 : mutex_unlock(&drm_global_mutex);
497 :
498 0 : drm_minor_release(minor);
499 :
500 0 : return 0;
501 : }
502 : EXPORT_SYMBOL(drm_release);
503 :
504 : /**
505 : * drm_release_noglobal - release method for DRM file
506 : * @inode: device inode
507 : * @filp: file pointer.
508 : *
509 : * This function may be used by drivers as their &file_operations.release
510 : * method. It frees any resources associated with the open file prior to taking
511 : * the drm_global_mutex, which then calls the &drm_driver.postclose driver
512 : * callback. If this is the last open file for the DRM device also proceeds to
513 : * call the &drm_driver.lastclose driver callback.
514 : *
515 : * RETURNS:
516 : *
517 : * Always succeeds and returns 0.
518 : */
519 0 : int drm_release_noglobal(struct inode *inode, struct file *filp)
520 : {
521 0 : struct drm_file *file_priv = filp->private_data;
522 0 : struct drm_minor *minor = file_priv->minor;
523 0 : struct drm_device *dev = minor->dev;
524 :
525 0 : drm_close_helper(filp);
526 :
527 0 : if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) {
528 0 : drm_lastclose(dev);
529 0 : mutex_unlock(&drm_global_mutex);
530 : }
531 :
532 0 : drm_minor_release(minor);
533 :
534 0 : return 0;
535 : }
536 : EXPORT_SYMBOL(drm_release_noglobal);
537 :
538 : /**
539 : * drm_read - read method for DRM file
540 : * @filp: file pointer
541 : * @buffer: userspace destination pointer for the read
542 : * @count: count in bytes to read
543 : * @offset: offset to read
544 : *
545 : * This function must be used by drivers as their &file_operations.read
546 : * method if they use DRM events for asynchronous signalling to userspace.
547 : * Since events are used by the KMS API for vblank and page flip completion this
548 : * means all modern display drivers must use it.
549 : *
550 : * @offset is ignored, DRM events are read like a pipe. Polling support is
551 : * provided by drm_poll().
552 : *
553 : * This function will only ever read a full event. Therefore userspace must
554 : * supply a big enough buffer to fit any event to ensure forward progress. Since
555 : * the maximum event space is currently 4K it's recommended to just use that for
556 : * safety.
557 : *
558 : * RETURNS:
559 : *
560 : * Number of bytes read (always aligned to full events, and can be 0) or a
561 : * negative error code on failure.
562 : */
563 0 : ssize_t drm_read(struct file *filp, char __user *buffer,
564 : size_t count, loff_t *offset)
565 : {
566 0 : struct drm_file *file_priv = filp->private_data;
567 0 : struct drm_device *dev = file_priv->minor->dev;
568 : ssize_t ret;
569 :
570 0 : ret = mutex_lock_interruptible(&file_priv->event_read_lock);
571 0 : if (ret)
572 : return ret;
573 :
574 : for (;;) {
575 0 : struct drm_pending_event *e = NULL;
576 :
577 0 : spin_lock_irq(&dev->event_lock);
578 0 : if (!list_empty(&file_priv->event_list)) {
579 0 : e = list_first_entry(&file_priv->event_list,
580 : struct drm_pending_event, link);
581 0 : file_priv->event_space += e->event->length;
582 0 : list_del(&e->link);
583 : }
584 0 : spin_unlock_irq(&dev->event_lock);
585 :
586 0 : if (e == NULL) {
587 0 : if (ret)
588 : break;
589 :
590 0 : if (filp->f_flags & O_NONBLOCK) {
591 : ret = -EAGAIN;
592 : break;
593 : }
594 :
595 0 : mutex_unlock(&file_priv->event_read_lock);
596 0 : ret = wait_event_interruptible(file_priv->event_wait,
597 : !list_empty(&file_priv->event_list));
598 0 : if (ret >= 0)
599 0 : ret = mutex_lock_interruptible(&file_priv->event_read_lock);
600 0 : if (ret)
601 : return ret;
602 : } else {
603 0 : unsigned length = e->event->length;
604 :
605 0 : if (length > count - ret) {
606 : put_back_event:
607 0 : spin_lock_irq(&dev->event_lock);
608 0 : file_priv->event_space -= length;
609 0 : list_add(&e->link, &file_priv->event_list);
610 0 : spin_unlock_irq(&dev->event_lock);
611 0 : wake_up_interruptible_poll(&file_priv->event_wait,
612 : EPOLLIN | EPOLLRDNORM);
613 0 : break;
614 : }
615 :
616 0 : if (copy_to_user(buffer + ret, e->event, length)) {
617 0 : if (ret == 0)
618 0 : ret = -EFAULT;
619 : goto put_back_event;
620 : }
621 :
622 0 : ret += length;
623 0 : kfree(e);
624 : }
625 : }
626 0 : mutex_unlock(&file_priv->event_read_lock);
627 :
628 0 : return ret;
629 : }
630 : EXPORT_SYMBOL(drm_read);
631 :
632 : /**
633 : * drm_poll - poll method for DRM file
634 : * @filp: file pointer
635 : * @wait: poll waiter table
636 : *
637 : * This function must be used by drivers as their &file_operations.read method
638 : * if they use DRM events for asynchronous signalling to userspace. Since
639 : * events are used by the KMS API for vblank and page flip completion this means
640 : * all modern display drivers must use it.
641 : *
642 : * See also drm_read().
643 : *
644 : * RETURNS:
645 : *
646 : * Mask of POLL flags indicating the current status of the file.
647 : */
648 0 : __poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
649 : {
650 0 : struct drm_file *file_priv = filp->private_data;
651 0 : __poll_t mask = 0;
652 :
653 0 : poll_wait(filp, &file_priv->event_wait, wait);
654 :
655 0 : if (!list_empty(&file_priv->event_list))
656 0 : mask |= EPOLLIN | EPOLLRDNORM;
657 :
658 0 : return mask;
659 : }
660 : EXPORT_SYMBOL(drm_poll);
661 :
662 : /**
663 : * drm_event_reserve_init_locked - init a DRM event and reserve space for it
664 : * @dev: DRM device
665 : * @file_priv: DRM file private data
666 : * @p: tracking structure for the pending event
667 : * @e: actual event data to deliver to userspace
668 : *
669 : * This function prepares the passed in event for eventual delivery. If the event
670 : * doesn't get delivered (because the IOCTL fails later on, before queuing up
671 : * anything) then the even must be cancelled and freed using
672 : * drm_event_cancel_free(). Successfully initialized events should be sent out
673 : * using drm_send_event() or drm_send_event_locked() to signal completion of the
674 : * asynchronous event to userspace.
675 : *
676 : * If callers embedded @p into a larger structure it must be allocated with
677 : * kmalloc and @p must be the first member element.
678 : *
679 : * This is the locked version of drm_event_reserve_init() for callers which
680 : * already hold &drm_device.event_lock.
681 : *
682 : * RETURNS:
683 : *
684 : * 0 on success or a negative error code on failure.
685 : */
686 0 : int drm_event_reserve_init_locked(struct drm_device *dev,
687 : struct drm_file *file_priv,
688 : struct drm_pending_event *p,
689 : struct drm_event *e)
690 : {
691 0 : if (file_priv->event_space < e->length)
692 : return -ENOMEM;
693 :
694 0 : file_priv->event_space -= e->length;
695 :
696 0 : p->event = e;
697 0 : list_add(&p->pending_link, &file_priv->pending_event_list);
698 0 : p->file_priv = file_priv;
699 :
700 0 : return 0;
701 : }
702 : EXPORT_SYMBOL(drm_event_reserve_init_locked);
703 :
704 : /**
705 : * drm_event_reserve_init - init a DRM event and reserve space for it
706 : * @dev: DRM device
707 : * @file_priv: DRM file private data
708 : * @p: tracking structure for the pending event
709 : * @e: actual event data to deliver to userspace
710 : *
711 : * This function prepares the passed in event for eventual delivery. If the event
712 : * doesn't get delivered (because the IOCTL fails later on, before queuing up
713 : * anything) then the even must be cancelled and freed using
714 : * drm_event_cancel_free(). Successfully initialized events should be sent out
715 : * using drm_send_event() or drm_send_event_locked() to signal completion of the
716 : * asynchronous event to userspace.
717 : *
718 : * If callers embedded @p into a larger structure it must be allocated with
719 : * kmalloc and @p must be the first member element.
720 : *
721 : * Callers which already hold &drm_device.event_lock should use
722 : * drm_event_reserve_init_locked() instead.
723 : *
724 : * RETURNS:
725 : *
726 : * 0 on success or a negative error code on failure.
727 : */
728 0 : int drm_event_reserve_init(struct drm_device *dev,
729 : struct drm_file *file_priv,
730 : struct drm_pending_event *p,
731 : struct drm_event *e)
732 : {
733 : unsigned long flags;
734 : int ret;
735 :
736 0 : spin_lock_irqsave(&dev->event_lock, flags);
737 0 : ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
738 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
739 :
740 0 : return ret;
741 : }
742 : EXPORT_SYMBOL(drm_event_reserve_init);
743 :
744 : /**
745 : * drm_event_cancel_free - free a DRM event and release its space
746 : * @dev: DRM device
747 : * @p: tracking structure for the pending event
748 : *
749 : * This function frees the event @p initialized with drm_event_reserve_init()
750 : * and releases any allocated space. It is used to cancel an event when the
751 : * nonblocking operation could not be submitted and needed to be aborted.
752 : */
753 0 : void drm_event_cancel_free(struct drm_device *dev,
754 : struct drm_pending_event *p)
755 : {
756 : unsigned long flags;
757 :
758 0 : spin_lock_irqsave(&dev->event_lock, flags);
759 0 : if (p->file_priv) {
760 0 : p->file_priv->event_space += p->event->length;
761 0 : list_del(&p->pending_link);
762 : }
763 0 : spin_unlock_irqrestore(&dev->event_lock, flags);
764 :
765 0 : if (p->fence)
766 0 : dma_fence_put(p->fence);
767 :
768 0 : kfree(p);
769 0 : }
770 : EXPORT_SYMBOL(drm_event_cancel_free);
771 :
772 0 : static void drm_send_event_helper(struct drm_device *dev,
773 : struct drm_pending_event *e, ktime_t timestamp)
774 : {
775 : assert_spin_locked(&dev->event_lock);
776 :
777 0 : if (e->completion) {
778 0 : complete_all(e->completion);
779 0 : e->completion_release(e->completion);
780 0 : e->completion = NULL;
781 : }
782 :
783 0 : if (e->fence) {
784 0 : if (timestamp)
785 0 : dma_fence_signal_timestamp(e->fence, timestamp);
786 : else
787 0 : dma_fence_signal(e->fence);
788 0 : dma_fence_put(e->fence);
789 : }
790 :
791 0 : if (!e->file_priv) {
792 0 : kfree(e);
793 : return;
794 : }
795 :
796 0 : list_del(&e->pending_link);
797 0 : list_add_tail(&e->link,
798 0 : &e->file_priv->event_list);
799 0 : wake_up_interruptible_poll(&e->file_priv->event_wait,
800 : EPOLLIN | EPOLLRDNORM);
801 : }
802 :
803 : /**
804 : * drm_send_event_timestamp_locked - send DRM event to file descriptor
805 : * @dev: DRM device
806 : * @e: DRM event to deliver
807 : * @timestamp: timestamp to set for the fence event in kernel's CLOCK_MONOTONIC
808 : * time domain
809 : *
810 : * This function sends the event @e, initialized with drm_event_reserve_init(),
811 : * to its associated userspace DRM file. Callers must already hold
812 : * &drm_device.event_lock.
813 : *
814 : * Note that the core will take care of unlinking and disarming events when the
815 : * corresponding DRM file is closed. Drivers need not worry about whether the
816 : * DRM file for this event still exists and can call this function upon
817 : * completion of the asynchronous work unconditionally.
818 : */
819 0 : void drm_send_event_timestamp_locked(struct drm_device *dev,
820 : struct drm_pending_event *e, ktime_t timestamp)
821 : {
822 0 : drm_send_event_helper(dev, e, timestamp);
823 0 : }
824 : EXPORT_SYMBOL(drm_send_event_timestamp_locked);
825 :
826 : /**
827 : * drm_send_event_locked - send DRM event to file descriptor
828 : * @dev: DRM device
829 : * @e: DRM event to deliver
830 : *
831 : * This function sends the event @e, initialized with drm_event_reserve_init(),
832 : * to its associated userspace DRM file. Callers must already hold
833 : * &drm_device.event_lock, see drm_send_event() for the unlocked version.
834 : *
835 : * Note that the core will take care of unlinking and disarming events when the
836 : * corresponding DRM file is closed. Drivers need not worry about whether the
837 : * DRM file for this event still exists and can call this function upon
838 : * completion of the asynchronous work unconditionally.
839 : */
840 0 : void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
841 : {
842 0 : drm_send_event_helper(dev, e, 0);
843 0 : }
844 : EXPORT_SYMBOL(drm_send_event_locked);
845 :
846 : /**
847 : * drm_send_event - send DRM event to file descriptor
848 : * @dev: DRM device
849 : * @e: DRM event to deliver
850 : *
851 : * This function sends the event @e, initialized with drm_event_reserve_init(),
852 : * to its associated userspace DRM file. This function acquires
853 : * &drm_device.event_lock, see drm_send_event_locked() for callers which already
854 : * hold this lock.
855 : *
856 : * Note that the core will take care of unlinking and disarming events when the
857 : * corresponding DRM file is closed. Drivers need not worry about whether the
858 : * DRM file for this event still exists and can call this function upon
859 : * completion of the asynchronous work unconditionally.
860 : */
861 0 : void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
862 : {
863 : unsigned long irqflags;
864 :
865 0 : spin_lock_irqsave(&dev->event_lock, irqflags);
866 0 : drm_send_event_helper(dev, e, 0);
867 0 : spin_unlock_irqrestore(&dev->event_lock, irqflags);
868 0 : }
869 : EXPORT_SYMBOL(drm_send_event);
870 :
871 : /**
872 : * mock_drm_getfile - Create a new struct file for the drm device
873 : * @minor: drm minor to wrap (e.g. #drm_device.primary)
874 : * @flags: file creation mode (O_RDWR etc)
875 : *
876 : * This create a new struct file that wraps a DRM file context around a
877 : * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without
878 : * invoking userspace. The struct file may be operated on using its f_op
879 : * (the drm_device.driver.fops) to mimick userspace operations, or be supplied
880 : * to userspace facing functions as an internal/anonymous client.
881 : *
882 : * RETURNS:
883 : * Pointer to newly created struct file, ERR_PTR on failure.
884 : */
885 0 : struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
886 : {
887 0 : struct drm_device *dev = minor->dev;
888 : struct drm_file *priv;
889 : struct file *file;
890 :
891 0 : priv = drm_file_alloc(minor);
892 0 : if (IS_ERR(priv))
893 : return ERR_CAST(priv);
894 :
895 0 : file = anon_inode_getfile("drm", dev->driver->fops, priv, flags);
896 0 : if (IS_ERR(file)) {
897 0 : drm_file_free(priv);
898 0 : return file;
899 : }
900 :
901 : /* Everyone shares a single global address space */
902 0 : file->f_mapping = dev->anon_inode->i_mapping;
903 :
904 0 : drm_dev_get(dev);
905 0 : priv->filp = file;
906 :
907 0 : return file;
908 : }
909 : EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
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