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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#include <linux/vga_switcheroo.h>
42
43#include <drm/drm_client_event.h>
44#include <drm/drm_drv.h>
45#include <drm/drm_file.h>
46#include <drm/drm_gem.h>
47#include <drm/drm_print.h>
48
49#include "drm_crtc_internal.h"
50#include "drm_internal.h"
51
52/* from BKL pushdown */
53DEFINE_MUTEX(drm_global_mutex);
54
55bool drm_dev_needs_global_mutex(struct drm_device *dev)
56{
57 /*
58 * The deprecated ->load callback must be called after the driver is
59 * already registered. This means such drivers rely on the BKL to make
60 * sure an open can't proceed until the driver is actually fully set up.
61 * Similar hilarity holds for the unload callback.
62 */
63 if (dev->driver->load || dev->driver->unload)
64 return true;
65
66 return false;
67}
68
69/**
70 * DOC: file operations
71 *
72 * Drivers must define the file operations structure that forms the DRM
73 * userspace API entry point, even though most of those operations are
74 * implemented in the DRM core. The resulting &struct file_operations must be
75 * stored in the &drm_driver.fops field. The mandatory functions are drm_open(),
76 * drm_read(), drm_ioctl() and drm_compat_ioctl() if CONFIG_COMPAT is enabled
77 * Note that drm_compat_ioctl will be NULL if CONFIG_COMPAT=n, so there's no
78 * need to sprinkle #ifdef into the code. Drivers which implement private ioctls
79 * that require 32/64 bit compatibility support must provide their own
80 * &file_operations.compat_ioctl handler that processes private ioctls and calls
81 * drm_compat_ioctl() for core ioctls.
82 *
83 * In addition drm_read() and drm_poll() provide support for DRM events. DRM
84 * events are a generic and extensible means to send asynchronous events to
85 * userspace through the file descriptor. They are used to send vblank event and
86 * page flip completions by the KMS API. But drivers can also use it for their
87 * own needs, e.g. to signal completion of rendering.
88 *
89 * For the driver-side event interface see drm_event_reserve_init() and
90 * drm_send_event() as the main starting points.
91 *
92 * The memory mapping implementation will vary depending on how the driver
93 * manages memory. For GEM-based drivers this is drm_gem_mmap().
94 *
95 * No other file operations are supported by the DRM userspace API. Overall the
96 * following is an example &file_operations structure::
97 *
98 * static const example_drm_fops = {
99 * .owner = THIS_MODULE,
100 * .open = drm_open,
101 * .release = drm_release,
102 * .unlocked_ioctl = drm_ioctl,
103 * .compat_ioctl = drm_compat_ioctl, // NULL if CONFIG_COMPAT=n
104 * .poll = drm_poll,
105 * .read = drm_read,
106 * .mmap = drm_gem_mmap,
107 * };
108 *
109 * For plain GEM based drivers there is the DEFINE_DRM_GEM_FOPS() macro, and for
110 * DMA based drivers there is the DEFINE_DRM_GEM_DMA_FOPS() macro to make this
111 * simpler.
112 *
113 * The driver's &file_operations must be stored in &drm_driver.fops.
114 *
115 * For driver-private IOCTL handling see the more detailed discussion in
116 * :ref:`IOCTL support in the userland interfaces chapter<drm_driver_ioctl>`.
117 */
118
119/**
120 * drm_file_alloc - allocate file context
121 * @minor: minor to allocate on
122 *
123 * This allocates a new DRM file context. It is not linked into any context and
124 * can be used by the caller freely. Note that the context keeps a pointer to
125 * @minor, so it must be freed before @minor is.
126 *
127 * RETURNS:
128 * Pointer to newly allocated context, ERR_PTR on failure.
129 */
130struct drm_file *drm_file_alloc(struct drm_minor *minor)
131{
132 static atomic64_t ident = ATOMIC64_INIT(0);
133 struct drm_device *dev = minor->dev;
134 struct drm_file *file;
135 int ret;
136
137 file = kzalloc(sizeof(*file), GFP_KERNEL);
138 if (!file)
139 return ERR_PTR(-ENOMEM);
140
141 /* Get a unique identifier for fdinfo: */
142 file->client_id = atomic64_inc_return(&ident);
143 rcu_assign_pointer(file->pid, get_pid(task_tgid(current)));
144 file->minor = minor;
145
146 /* for compatibility root is always authenticated */
147 file->authenticated = capable(CAP_SYS_ADMIN);
148
149 INIT_LIST_HEAD(&file->lhead);
150 INIT_LIST_HEAD(&file->fbs);
151 mutex_init(&file->fbs_lock);
152 INIT_LIST_HEAD(&file->blobs);
153 INIT_LIST_HEAD(&file->pending_event_list);
154 INIT_LIST_HEAD(&file->event_list);
155 init_waitqueue_head(&file->event_wait);
156 file->event_space = 4096; /* set aside 4k for event buffer */
157
158 spin_lock_init(&file->master_lookup_lock);
159 mutex_init(&file->event_read_lock);
160 mutex_init(&file->client_name_lock);
161
162 if (drm_core_check_feature(dev, DRIVER_GEM))
163 drm_gem_open(dev, file);
164
165 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
166 drm_syncobj_open(file);
167
168 drm_prime_init_file_private(&file->prime);
169
170 if (dev->driver->open) {
171 ret = dev->driver->open(dev, file);
172 if (ret < 0)
173 goto out_prime_destroy;
174 }
175
176 return file;
177
178out_prime_destroy:
179 drm_prime_destroy_file_private(&file->prime);
180 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
181 drm_syncobj_release(file);
182 if (drm_core_check_feature(dev, DRIVER_GEM))
183 drm_gem_release(dev, file);
184 put_pid(rcu_access_pointer(file->pid));
185 kfree(file);
186
187 return ERR_PTR(ret);
188}
189
190static void drm_events_release(struct drm_file *file_priv)
191{
192 struct drm_device *dev = file_priv->minor->dev;
193 struct drm_pending_event *e, *et;
194 unsigned long flags;
195
196 spin_lock_irqsave(&dev->event_lock, flags);
197
198 /* Unlink pending events */
199 list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
200 pending_link) {
201 list_del(&e->pending_link);
202 e->file_priv = NULL;
203 }
204
205 /* Remove unconsumed events */
206 list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
207 list_del(&e->link);
208 kfree(e);
209 }
210
211 spin_unlock_irqrestore(&dev->event_lock, flags);
212}
213
214/**
215 * drm_file_free - free file context
216 * @file: context to free, or NULL
217 *
218 * This destroys and deallocates a DRM file context previously allocated via
219 * drm_file_alloc(). The caller must make sure to unlink it from any contexts
220 * before calling this.
221 *
222 * If NULL is passed, this is a no-op.
223 */
224void drm_file_free(struct drm_file *file)
225{
226 struct drm_device *dev;
227
228 if (!file)
229 return;
230
231 dev = file->minor->dev;
232
233 drm_dbg_core(dev, "comm=\"%s\", pid=%d, dev=0x%lx, open_count=%d\n",
234 current->comm, task_pid_nr(current),
235 (long)old_encode_dev(file->minor->kdev->devt),
236 atomic_read(&dev->open_count));
237
238 drm_events_release(file);
239
240 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
241 drm_fb_release(file);
242 drm_property_destroy_user_blobs(dev, file);
243 }
244
245 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
246 drm_syncobj_release(file);
247
248 if (drm_core_check_feature(dev, DRIVER_GEM))
249 drm_gem_release(dev, file);
250
251 if (drm_is_primary_client(file))
252 drm_master_release(file);
253
254 if (dev->driver->postclose)
255 dev->driver->postclose(dev, file);
256
257 drm_prime_destroy_file_private(&file->prime);
258
259 WARN_ON(!list_empty(&file->event_list));
260
261 put_pid(rcu_access_pointer(file->pid));
262
263 mutex_destroy(&file->client_name_lock);
264 kfree(file->client_name);
265
266 kfree(file);
267}
268
269static void drm_close_helper(struct file *filp)
270{
271 struct drm_file *file_priv = filp->private_data;
272 struct drm_device *dev = file_priv->minor->dev;
273
274 mutex_lock(&dev->filelist_mutex);
275 list_del(&file_priv->lhead);
276 mutex_unlock(&dev->filelist_mutex);
277
278 drm_file_free(file_priv);
279}
280
281/*
282 * Check whether DRI will run on this CPU.
283 *
284 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
285 */
286static int drm_cpu_valid(void)
287{
288#if defined(__sparc__) && !defined(__sparc_v9__)
289 return 0; /* No cmpxchg before v9 sparc. */
290#endif
291 return 1;
292}
293
294/*
295 * Called whenever a process opens a drm node
296 *
297 * \param filp file pointer.
298 * \param minor acquired minor-object.
299 * \return zero on success or a negative number on failure.
300 *
301 * Creates and initializes a drm_file structure for the file private data in \p
302 * filp and add it into the double linked list in \p dev.
303 */
304int drm_open_helper(struct file *filp, struct drm_minor *minor)
305{
306 struct drm_device *dev = minor->dev;
307 struct drm_file *priv;
308 int ret;
309
310 if (filp->f_flags & O_EXCL)
311 return -EBUSY; /* No exclusive opens */
312 if (!drm_cpu_valid())
313 return -EINVAL;
314 if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
315 dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
316 return -EINVAL;
317 if (WARN_ON_ONCE(!(filp->f_op->fop_flags & FOP_UNSIGNED_OFFSET)))
318 return -EINVAL;
319
320 drm_dbg_core(dev, "comm=\"%s\", pid=%d, minor=%d\n",
321 current->comm, task_pid_nr(current), minor->index);
322
323 priv = drm_file_alloc(minor);
324 if (IS_ERR(priv))
325 return PTR_ERR(priv);
326
327 if (drm_is_primary_client(priv)) {
328 ret = drm_master_open(priv);
329 if (ret) {
330 drm_file_free(priv);
331 return ret;
332 }
333 }
334
335 filp->private_data = priv;
336 priv->filp = filp;
337
338 mutex_lock(&dev->filelist_mutex);
339 list_add(&priv->lhead, &dev->filelist);
340 mutex_unlock(&dev->filelist_mutex);
341
342 return 0;
343}
344
345/**
346 * drm_open - open method for DRM file
347 * @inode: device inode
348 * @filp: file pointer.
349 *
350 * This function must be used by drivers as their &file_operations.open method.
351 * It looks up the correct DRM device and instantiates all the per-file
352 * resources for it. It also calls the &drm_driver.open driver callback.
353 *
354 * RETURNS:
355 * 0 on success or negative errno value on failure.
356 */
357int drm_open(struct inode *inode, struct file *filp)
358{
359 struct drm_device *dev;
360 struct drm_minor *minor;
361 int retcode;
362
363 minor = drm_minor_acquire(&drm_minors_xa, iminor(inode));
364 if (IS_ERR(minor))
365 return PTR_ERR(minor);
366
367 dev = minor->dev;
368 if (drm_dev_needs_global_mutex(dev))
369 mutex_lock(&drm_global_mutex);
370
371 atomic_fetch_inc(&dev->open_count);
372
373 /* share address_space across all char-devs of a single device */
374 filp->f_mapping = dev->anon_inode->i_mapping;
375
376 retcode = drm_open_helper(filp, minor);
377 if (retcode)
378 goto err_undo;
379
380 if (drm_dev_needs_global_mutex(dev))
381 mutex_unlock(&drm_global_mutex);
382
383 return 0;
384
385err_undo:
386 atomic_dec(&dev->open_count);
387 if (drm_dev_needs_global_mutex(dev))
388 mutex_unlock(&drm_global_mutex);
389 drm_minor_release(minor);
390 return retcode;
391}
392EXPORT_SYMBOL(drm_open);
393
394static void drm_lastclose(struct drm_device *dev)
395{
396 drm_client_dev_restore(dev);
397
398 if (dev_is_pci(dev->dev))
399 vga_switcheroo_process_delayed_switch();
400}
401
402/**
403 * drm_release - release method for DRM file
404 * @inode: device inode
405 * @filp: file pointer.
406 *
407 * This function must be used by drivers as their &file_operations.release
408 * method. It frees any resources associated with the open file. If this
409 * is the last open file for the DRM device, it also restores the active
410 * in-kernel DRM client.
411 *
412 * RETURNS:
413 * Always succeeds and returns 0.
414 */
415int drm_release(struct inode *inode, struct file *filp)
416{
417 struct drm_file *file_priv = filp->private_data;
418 struct drm_minor *minor = file_priv->minor;
419 struct drm_device *dev = minor->dev;
420
421 if (drm_dev_needs_global_mutex(dev))
422 mutex_lock(&drm_global_mutex);
423
424 drm_dbg_core(dev, "open_count = %d\n", atomic_read(&dev->open_count));
425
426 drm_close_helper(filp);
427
428 if (atomic_dec_and_test(&dev->open_count))
429 drm_lastclose(dev);
430
431 if (drm_dev_needs_global_mutex(dev))
432 mutex_unlock(&drm_global_mutex);
433
434 drm_minor_release(minor);
435
436 return 0;
437}
438EXPORT_SYMBOL(drm_release);
439
440void drm_file_update_pid(struct drm_file *filp)
441{
442 struct drm_device *dev;
443 struct pid *pid, *old;
444
445 /*
446 * Master nodes need to keep the original ownership in order for
447 * drm_master_check_perm to keep working correctly. (See comment in
448 * drm_auth.c.)
449 */
450 if (filp->was_master)
451 return;
452
453 pid = task_tgid(current);
454
455 /*
456 * Quick unlocked check since the model is a single handover followed by
457 * exclusive repeated use.
458 */
459 if (pid == rcu_access_pointer(filp->pid))
460 return;
461
462 dev = filp->minor->dev;
463 mutex_lock(&dev->filelist_mutex);
464 get_pid(pid);
465 old = rcu_replace_pointer(filp->pid, pid, 1);
466 mutex_unlock(&dev->filelist_mutex);
467
468 synchronize_rcu();
469 put_pid(old);
470}
471
472/**
473 * drm_release_noglobal - release method for DRM file
474 * @inode: device inode
475 * @filp: file pointer.
476 *
477 * This function may be used by drivers as their &file_operations.release
478 * method. It frees any resources associated with the open file prior to taking
479 * the drm_global_mutex. If this is the last open file for the DRM device, it
480 * then restores the active in-kernel DRM client.
481 *
482 * RETURNS:
483 * Always succeeds and returns 0.
484 */
485int drm_release_noglobal(struct inode *inode, struct file *filp)
486{
487 struct drm_file *file_priv = filp->private_data;
488 struct drm_minor *minor = file_priv->minor;
489 struct drm_device *dev = minor->dev;
490
491 drm_close_helper(filp);
492
493 if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) {
494 drm_lastclose(dev);
495 mutex_unlock(&drm_global_mutex);
496 }
497
498 drm_minor_release(minor);
499
500 return 0;
501}
502EXPORT_SYMBOL(drm_release_noglobal);
503
504/**
505 * drm_read - read method for DRM file
506 * @filp: file pointer
507 * @buffer: userspace destination pointer for the read
508 * @count: count in bytes to read
509 * @offset: offset to read
510 *
511 * This function must be used by drivers as their &file_operations.read
512 * method if they use DRM events for asynchronous signalling to userspace.
513 * Since events are used by the KMS API for vblank and page flip completion this
514 * means all modern display drivers must use it.
515 *
516 * @offset is ignored, DRM events are read like a pipe. Polling support is
517 * provided by drm_poll().
518 *
519 * This function will only ever read a full event. Therefore userspace must
520 * supply a big enough buffer to fit any event to ensure forward progress. Since
521 * the maximum event space is currently 4K it's recommended to just use that for
522 * safety.
523 *
524 * RETURNS:
525 * Number of bytes read (always aligned to full events, and can be 0) or a
526 * negative error code on failure.
527 */
528ssize_t drm_read(struct file *filp, char __user *buffer,
529 size_t count, loff_t *offset)
530{
531 struct drm_file *file_priv = filp->private_data;
532 struct drm_device *dev = file_priv->minor->dev;
533 ssize_t ret;
534
535 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
536 if (ret)
537 return ret;
538
539 for (;;) {
540 struct drm_pending_event *e = NULL;
541
542 spin_lock_irq(&dev->event_lock);
543 if (!list_empty(&file_priv->event_list)) {
544 e = list_first_entry(&file_priv->event_list,
545 struct drm_pending_event, link);
546 file_priv->event_space += e->event->length;
547 list_del(&e->link);
548 }
549 spin_unlock_irq(&dev->event_lock);
550
551 if (e == NULL) {
552 if (ret)
553 break;
554
555 if (filp->f_flags & O_NONBLOCK) {
556 ret = -EAGAIN;
557 break;
558 }
559
560 mutex_unlock(&file_priv->event_read_lock);
561 ret = wait_event_interruptible(file_priv->event_wait,
562 !list_empty(&file_priv->event_list));
563 if (ret >= 0)
564 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
565 if (ret)
566 return ret;
567 } else {
568 unsigned length = e->event->length;
569
570 if (length > count - ret) {
571put_back_event:
572 spin_lock_irq(&dev->event_lock);
573 file_priv->event_space -= length;
574 list_add(&e->link, &file_priv->event_list);
575 spin_unlock_irq(&dev->event_lock);
576 wake_up_interruptible_poll(&file_priv->event_wait,
577 EPOLLIN | EPOLLRDNORM);
578 break;
579 }
580
581 if (copy_to_user(buffer + ret, e->event, length)) {
582 if (ret == 0)
583 ret = -EFAULT;
584 goto put_back_event;
585 }
586
587 ret += length;
588 kfree(e);
589 }
590 }
591 mutex_unlock(&file_priv->event_read_lock);
592
593 return ret;
594}
595EXPORT_SYMBOL(drm_read);
596
597/**
598 * drm_poll - poll method for DRM file
599 * @filp: file pointer
600 * @wait: poll waiter table
601 *
602 * This function must be used by drivers as their &file_operations.read method
603 * if they use DRM events for asynchronous signalling to userspace. Since
604 * events are used by the KMS API for vblank and page flip completion this means
605 * all modern display drivers must use it.
606 *
607 * See also drm_read().
608 *
609 * RETURNS:
610 * Mask of POLL flags indicating the current status of the file.
611 */
612__poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
613{
614 struct drm_file *file_priv = filp->private_data;
615 __poll_t mask = 0;
616
617 poll_wait(filp, &file_priv->event_wait, wait);
618
619 if (!list_empty(&file_priv->event_list))
620 mask |= EPOLLIN | EPOLLRDNORM;
621
622 return mask;
623}
624EXPORT_SYMBOL(drm_poll);
625
626/**
627 * drm_event_reserve_init_locked - init a DRM event and reserve space for it
628 * @dev: DRM device
629 * @file_priv: DRM file private data
630 * @p: tracking structure for the pending event
631 * @e: actual event data to deliver to userspace
632 *
633 * This function prepares the passed in event for eventual delivery. If the event
634 * doesn't get delivered (because the IOCTL fails later on, before queuing up
635 * anything) then the even must be cancelled and freed using
636 * drm_event_cancel_free(). Successfully initialized events should be sent out
637 * using drm_send_event() or drm_send_event_locked() to signal completion of the
638 * asynchronous event to userspace.
639 *
640 * If callers embedded @p into a larger structure it must be allocated with
641 * kmalloc and @p must be the first member element.
642 *
643 * This is the locked version of drm_event_reserve_init() for callers which
644 * already hold &drm_device.event_lock.
645 *
646 * RETURNS:
647 * 0 on success or a negative error code on failure.
648 */
649int drm_event_reserve_init_locked(struct drm_device *dev,
650 struct drm_file *file_priv,
651 struct drm_pending_event *p,
652 struct drm_event *e)
653{
654 if (file_priv->event_space < e->length)
655 return -ENOMEM;
656
657 file_priv->event_space -= e->length;
658
659 p->event = e;
660 list_add(&p->pending_link, &file_priv->pending_event_list);
661 p->file_priv = file_priv;
662
663 return 0;
664}
665EXPORT_SYMBOL(drm_event_reserve_init_locked);
666
667/**
668 * drm_event_reserve_init - init a DRM event and reserve space for it
669 * @dev: DRM device
670 * @file_priv: DRM file private data
671 * @p: tracking structure for the pending event
672 * @e: actual event data to deliver to userspace
673 *
674 * This function prepares the passed in event for eventual delivery. If the event
675 * doesn't get delivered (because the IOCTL fails later on, before queuing up
676 * anything) then the even must be cancelled and freed using
677 * drm_event_cancel_free(). Successfully initialized events should be sent out
678 * using drm_send_event() or drm_send_event_locked() to signal completion of the
679 * asynchronous event to userspace.
680 *
681 * If callers embedded @p into a larger structure it must be allocated with
682 * kmalloc and @p must be the first member element.
683 *
684 * Callers which already hold &drm_device.event_lock should use
685 * drm_event_reserve_init_locked() instead.
686 *
687 * RETURNS:
688 * 0 on success or a negative error code on failure.
689 */
690int drm_event_reserve_init(struct drm_device *dev,
691 struct drm_file *file_priv,
692 struct drm_pending_event *p,
693 struct drm_event *e)
694{
695 unsigned long flags;
696 int ret;
697
698 spin_lock_irqsave(&dev->event_lock, flags);
699 ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
700 spin_unlock_irqrestore(&dev->event_lock, flags);
701
702 return ret;
703}
704EXPORT_SYMBOL(drm_event_reserve_init);
705
706/**
707 * drm_event_cancel_free - free a DRM event and release its space
708 * @dev: DRM device
709 * @p: tracking structure for the pending event
710 *
711 * This function frees the event @p initialized with drm_event_reserve_init()
712 * and releases any allocated space. It is used to cancel an event when the
713 * nonblocking operation could not be submitted and needed to be aborted.
714 */
715void drm_event_cancel_free(struct drm_device *dev,
716 struct drm_pending_event *p)
717{
718 unsigned long flags;
719
720 spin_lock_irqsave(&dev->event_lock, flags);
721 if (p->file_priv) {
722 p->file_priv->event_space += p->event->length;
723 list_del(&p->pending_link);
724 }
725 spin_unlock_irqrestore(&dev->event_lock, flags);
726
727 if (p->fence)
728 dma_fence_put(p->fence);
729
730 kfree(p);
731}
732EXPORT_SYMBOL(drm_event_cancel_free);
733
734static void drm_send_event_helper(struct drm_device *dev,
735 struct drm_pending_event *e, ktime_t timestamp)
736{
737 assert_spin_locked(&dev->event_lock);
738
739 if (e->completion) {
740 complete_all(e->completion);
741 e->completion_release(e->completion);
742 e->completion = NULL;
743 }
744
745 if (e->fence) {
746 if (timestamp)
747 dma_fence_signal_timestamp(e->fence, timestamp);
748 else
749 dma_fence_signal(e->fence);
750 dma_fence_put(e->fence);
751 }
752
753 if (!e->file_priv) {
754 kfree(e);
755 return;
756 }
757
758 list_del(&e->pending_link);
759 list_add_tail(&e->link,
760 &e->file_priv->event_list);
761 wake_up_interruptible_poll(&e->file_priv->event_wait,
762 EPOLLIN | EPOLLRDNORM);
763}
764
765/**
766 * drm_send_event_timestamp_locked - send DRM event to file descriptor
767 * @dev: DRM device
768 * @e: DRM event to deliver
769 * @timestamp: timestamp to set for the fence event in kernel's CLOCK_MONOTONIC
770 * time domain
771 *
772 * This function sends the event @e, initialized with drm_event_reserve_init(),
773 * to its associated userspace DRM file. Callers must already hold
774 * &drm_device.event_lock.
775 *
776 * Note that the core will take care of unlinking and disarming events when the
777 * corresponding DRM file is closed. Drivers need not worry about whether the
778 * DRM file for this event still exists and can call this function upon
779 * completion of the asynchronous work unconditionally.
780 */
781void drm_send_event_timestamp_locked(struct drm_device *dev,
782 struct drm_pending_event *e, ktime_t timestamp)
783{
784 drm_send_event_helper(dev, e, timestamp);
785}
786EXPORT_SYMBOL(drm_send_event_timestamp_locked);
787
788/**
789 * drm_send_event_locked - send DRM event to file descriptor
790 * @dev: DRM device
791 * @e: DRM event to deliver
792 *
793 * This function sends the event @e, initialized with drm_event_reserve_init(),
794 * to its associated userspace DRM file. Callers must already hold
795 * &drm_device.event_lock, see drm_send_event() for the unlocked version.
796 *
797 * Note that the core will take care of unlinking and disarming events when the
798 * corresponding DRM file is closed. Drivers need not worry about whether the
799 * DRM file for this event still exists and can call this function upon
800 * completion of the asynchronous work unconditionally.
801 */
802void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
803{
804 drm_send_event_helper(dev, e, 0);
805}
806EXPORT_SYMBOL(drm_send_event_locked);
807
808/**
809 * drm_send_event - send DRM event to file descriptor
810 * @dev: DRM device
811 * @e: DRM event to deliver
812 *
813 * This function sends the event @e, initialized with drm_event_reserve_init(),
814 * to its associated userspace DRM file. This function acquires
815 * &drm_device.event_lock, see drm_send_event_locked() for callers which already
816 * hold this lock.
817 *
818 * Note that the core will take care of unlinking and disarming events when the
819 * corresponding DRM file is closed. Drivers need not worry about whether the
820 * DRM file for this event still exists and can call this function upon
821 * completion of the asynchronous work unconditionally.
822 */
823void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
824{
825 unsigned long irqflags;
826
827 spin_lock_irqsave(&dev->event_lock, irqflags);
828 drm_send_event_helper(dev, e, 0);
829 spin_unlock_irqrestore(&dev->event_lock, irqflags);
830}
831EXPORT_SYMBOL(drm_send_event);
832
833static void print_size(struct drm_printer *p, const char *stat,
834 const char *region, u64 sz)
835{
836 const char *units[] = {"", " KiB", " MiB"};
837 unsigned u;
838
839 for (u = 0; u < ARRAY_SIZE(units) - 1; u++) {
840 if (sz == 0 || !IS_ALIGNED(sz, SZ_1K))
841 break;
842 sz = div_u64(sz, SZ_1K);
843 }
844
845 drm_printf(p, "drm-%s-%s:\t%llu%s\n", stat, region, sz, units[u]);
846}
847
848/**
849 * drm_print_memory_stats - A helper to print memory stats
850 * @p: The printer to print output to
851 * @stats: The collected memory stats
852 * @supported_status: Bitmask of optional stats which are available
853 * @region: The memory region
854 *
855 */
856void drm_print_memory_stats(struct drm_printer *p,
857 const struct drm_memory_stats *stats,
858 enum drm_gem_object_status supported_status,
859 const char *region)
860{
861 print_size(p, "total", region, stats->private + stats->shared);
862 print_size(p, "shared", region, stats->shared);
863 print_size(p, "active", region, stats->active);
864
865 if (supported_status & DRM_GEM_OBJECT_RESIDENT)
866 print_size(p, "resident", region, stats->resident);
867
868 if (supported_status & DRM_GEM_OBJECT_PURGEABLE)
869 print_size(p, "purgeable", region, stats->purgeable);
870}
871EXPORT_SYMBOL(drm_print_memory_stats);
872
873/**
874 * drm_show_memory_stats - Helper to collect and show standard fdinfo memory stats
875 * @p: the printer to print output to
876 * @file: the DRM file
877 *
878 * Helper to iterate over GEM objects with a handle allocated in the specified
879 * file.
880 */
881void drm_show_memory_stats(struct drm_printer *p, struct drm_file *file)
882{
883 struct drm_gem_object *obj;
884 struct drm_memory_stats status = {};
885 enum drm_gem_object_status supported_status = 0;
886 int id;
887
888 spin_lock(&file->table_lock);
889 idr_for_each_entry (&file->object_idr, obj, id) {
890 enum drm_gem_object_status s = 0;
891 size_t add_size = (obj->funcs && obj->funcs->rss) ?
892 obj->funcs->rss(obj) : obj->size;
893
894 if (obj->funcs && obj->funcs->status) {
895 s = obj->funcs->status(obj);
896 supported_status = DRM_GEM_OBJECT_RESIDENT |
897 DRM_GEM_OBJECT_PURGEABLE;
898 }
899
900 if (drm_gem_object_is_shared_for_memory_stats(obj)) {
901 status.shared += obj->size;
902 } else {
903 status.private += obj->size;
904 }
905
906 if (s & DRM_GEM_OBJECT_RESIDENT) {
907 status.resident += add_size;
908 } else {
909 /* If already purged or not yet backed by pages, don't
910 * count it as purgeable:
911 */
912 s &= ~DRM_GEM_OBJECT_PURGEABLE;
913 }
914
915 if (!dma_resv_test_signaled(obj->resv, dma_resv_usage_rw(true))) {
916 status.active += add_size;
917
918 /* If still active, don't count as purgeable: */
919 s &= ~DRM_GEM_OBJECT_PURGEABLE;
920 }
921
922 if (s & DRM_GEM_OBJECT_PURGEABLE)
923 status.purgeable += add_size;
924 }
925 spin_unlock(&file->table_lock);
926
927 drm_print_memory_stats(p, &status, supported_status, "memory");
928}
929EXPORT_SYMBOL(drm_show_memory_stats);
930
931/**
932 * drm_show_fdinfo - helper for drm file fops
933 * @m: output stream
934 * @f: the device file instance
935 *
936 * Helper to implement fdinfo, for userspace to query usage stats, etc, of a
937 * process using the GPU. See also &drm_driver.show_fdinfo.
938 *
939 * For text output format description please see Documentation/gpu/drm-usage-stats.rst
940 */
941void drm_show_fdinfo(struct seq_file *m, struct file *f)
942{
943 struct drm_file *file = f->private_data;
944 struct drm_device *dev = file->minor->dev;
945 struct drm_printer p = drm_seq_file_printer(m);
946
947 drm_printf(&p, "drm-driver:\t%s\n", dev->driver->name);
948 drm_printf(&p, "drm-client-id:\t%llu\n", file->client_id);
949
950 if (dev_is_pci(dev->dev)) {
951 struct pci_dev *pdev = to_pci_dev(dev->dev);
952
953 drm_printf(&p, "drm-pdev:\t%04x:%02x:%02x.%d\n",
954 pci_domain_nr(pdev->bus), pdev->bus->number,
955 PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
956 }
957
958 mutex_lock(&file->client_name_lock);
959 if (file->client_name)
960 drm_printf(&p, "drm-client-name:\t%s\n", file->client_name);
961 mutex_unlock(&file->client_name_lock);
962
963 if (dev->driver->show_fdinfo)
964 dev->driver->show_fdinfo(&p, file);
965}
966EXPORT_SYMBOL(drm_show_fdinfo);
967
968/**
969 * mock_drm_getfile - Create a new struct file for the drm device
970 * @minor: drm minor to wrap (e.g. #drm_device.primary)
971 * @flags: file creation mode (O_RDWR etc)
972 *
973 * This create a new struct file that wraps a DRM file context around a
974 * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without
975 * invoking userspace. The struct file may be operated on using its f_op
976 * (the drm_device.driver.fops) to mimick userspace operations, or be supplied
977 * to userspace facing functions as an internal/anonymous client.
978 *
979 * RETURNS:
980 * Pointer to newly created struct file, ERR_PTR on failure.
981 */
982struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
983{
984 struct drm_device *dev = minor->dev;
985 struct drm_file *priv;
986 struct file *file;
987
988 priv = drm_file_alloc(minor);
989 if (IS_ERR(priv))
990 return ERR_CAST(priv);
991
992 file = anon_inode_getfile("drm", dev->driver->fops, priv, flags);
993 if (IS_ERR(file)) {
994 drm_file_free(priv);
995 return file;
996 }
997
998 /* Everyone shares a single global address space */
999 file->f_mapping = dev->anon_inode->i_mapping;
1000
1001 drm_dev_get(dev);
1002 priv->filp = file;
1003
1004 return file;
1005}
1006EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
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 */
52DEFINE_MUTEX(drm_global_mutex);
53
54bool 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 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 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 if (dev->driver->lastclose)
80 return true;
81
82 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 */
149struct drm_file *drm_file_alloc(struct drm_minor *minor)
150{
151 struct drm_device *dev = minor->dev;
152 struct drm_file *file;
153 int ret;
154
155 file = kzalloc(sizeof(*file), GFP_KERNEL);
156 if (!file)
157 return ERR_PTR(-ENOMEM);
158
159 file->pid = get_pid(task_pid(current));
160 file->minor = minor;
161
162 /* for compatibility root is always authenticated */
163 file->authenticated = capable(CAP_SYS_ADMIN);
164
165 INIT_LIST_HEAD(&file->lhead);
166 INIT_LIST_HEAD(&file->fbs);
167 mutex_init(&file->fbs_lock);
168 INIT_LIST_HEAD(&file->blobs);
169 INIT_LIST_HEAD(&file->pending_event_list);
170 INIT_LIST_HEAD(&file->event_list);
171 init_waitqueue_head(&file->event_wait);
172 file->event_space = 4096; /* set aside 4k for event buffer */
173
174 spin_lock_init(&file->master_lookup_lock);
175 mutex_init(&file->event_read_lock);
176
177 if (drm_core_check_feature(dev, DRIVER_GEM))
178 drm_gem_open(dev, file);
179
180 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
181 drm_syncobj_open(file);
182
183 drm_prime_init_file_private(&file->prime);
184
185 if (dev->driver->open) {
186 ret = dev->driver->open(dev, file);
187 if (ret < 0)
188 goto out_prime_destroy;
189 }
190
191 return file;
192
193out_prime_destroy:
194 drm_prime_destroy_file_private(&file->prime);
195 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
196 drm_syncobj_release(file);
197 if (drm_core_check_feature(dev, DRIVER_GEM))
198 drm_gem_release(dev, file);
199 put_pid(file->pid);
200 kfree(file);
201
202 return ERR_PTR(ret);
203}
204
205static void drm_events_release(struct drm_file *file_priv)
206{
207 struct drm_device *dev = file_priv->minor->dev;
208 struct drm_pending_event *e, *et;
209 unsigned long flags;
210
211 spin_lock_irqsave(&dev->event_lock, flags);
212
213 /* Unlink pending events */
214 list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
215 pending_link) {
216 list_del(&e->pending_link);
217 e->file_priv = NULL;
218 }
219
220 /* Remove unconsumed events */
221 list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
222 list_del(&e->link);
223 kfree(e);
224 }
225
226 spin_unlock_irqrestore(&dev->event_lock, flags);
227}
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 */
239void drm_file_free(struct drm_file *file)
240{
241 struct drm_device *dev;
242
243 if (!file)
244 return;
245
246 dev = file->minor->dev;
247
248 DRM_DEBUG("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 if (drm_core_check_feature(dev, DRIVER_LEGACY))
260 drm_legacy_lock_release(dev, file->filp);
261
262 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
263 drm_legacy_reclaim_buffers(dev, file);
264
265 drm_events_release(file);
266
267 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
268 drm_fb_release(file);
269 drm_property_destroy_user_blobs(dev, file);
270 }
271
272 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
273 drm_syncobj_release(file);
274
275 if (drm_core_check_feature(dev, DRIVER_GEM))
276 drm_gem_release(dev, file);
277
278 drm_legacy_ctxbitmap_flush(dev, file);
279
280 if (drm_is_primary_client(file))
281 drm_master_release(file);
282
283 if (dev->driver->postclose)
284 dev->driver->postclose(dev, file);
285
286 drm_prime_destroy_file_private(&file->prime);
287
288 WARN_ON(!list_empty(&file->event_list));
289
290 put_pid(file->pid);
291 kfree(file);
292}
293
294static void drm_close_helper(struct file *filp)
295{
296 struct drm_file *file_priv = filp->private_data;
297 struct drm_device *dev = file_priv->minor->dev;
298
299 mutex_lock(&dev->filelist_mutex);
300 list_del(&file_priv->lhead);
301 mutex_unlock(&dev->filelist_mutex);
302
303 drm_file_free(file_priv);
304}
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 */
311static 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 */
329int drm_open_helper(struct file *filp, struct drm_minor *minor)
330{
331 struct drm_device *dev = minor->dev;
332 struct drm_file *priv;
333 int ret;
334
335 if (filp->f_flags & O_EXCL)
336 return -EBUSY; /* No exclusive opens */
337 if (!drm_cpu_valid())
338 return -EINVAL;
339 if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
340 dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
341 return -EINVAL;
342
343 DRM_DEBUG("comm=\"%s\", pid=%d, minor=%d\n", current->comm,
344 task_pid_nr(current), minor->index);
345
346 priv = drm_file_alloc(minor);
347 if (IS_ERR(priv))
348 return PTR_ERR(priv);
349
350 if (drm_is_primary_client(priv)) {
351 ret = drm_master_open(priv);
352 if (ret) {
353 drm_file_free(priv);
354 return ret;
355 }
356 }
357
358 filp->private_data = priv;
359 filp->f_mode |= FMODE_UNSIGNED_OFFSET;
360 priv->filp = filp;
361
362 mutex_lock(&dev->filelist_mutex);
363 list_add(&priv->lhead, &dev->filelist);
364 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 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 */
405int drm_open(struct inode *inode, struct file *filp)
406{
407 struct drm_device *dev;
408 struct drm_minor *minor;
409 int retcode;
410 int need_setup = 0;
411
412 minor = drm_minor_acquire(iminor(inode));
413 if (IS_ERR(minor))
414 return PTR_ERR(minor);
415
416 dev = minor->dev;
417 if (drm_dev_needs_global_mutex(dev))
418 mutex_lock(&drm_global_mutex);
419
420 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 filp->f_mapping = dev->anon_inode->i_mapping;
425
426 retcode = drm_open_helper(filp, minor);
427 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 if (drm_dev_needs_global_mutex(dev))
438 mutex_unlock(&drm_global_mutex);
439
440 return 0;
441
442err_undo:
443 atomic_dec(&dev->open_count);
444 if (drm_dev_needs_global_mutex(dev))
445 mutex_unlock(&drm_global_mutex);
446 drm_minor_release(minor);
447 return retcode;
448}
449EXPORT_SYMBOL(drm_open);
450
451void drm_lastclose(struct drm_device * dev)
452{
453 DRM_DEBUG("\n");
454
455 if (dev->driver->lastclose)
456 dev->driver->lastclose(dev);
457 DRM_DEBUG("driver lastclose completed\n");
458
459 if (drm_core_check_feature(dev, DRIVER_LEGACY))
460 drm_legacy_dev_reinit(dev);
461
462 drm_client_dev_restore(dev);
463}
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 */
479int drm_release(struct inode *inode, struct file *filp)
480{
481 struct drm_file *file_priv = filp->private_data;
482 struct drm_minor *minor = file_priv->minor;
483 struct drm_device *dev = minor->dev;
484
485 if (drm_dev_needs_global_mutex(dev))
486 mutex_lock(&drm_global_mutex);
487
488 DRM_DEBUG("open_count = %d\n", atomic_read(&dev->open_count));
489
490 drm_close_helper(filp);
491
492 if (atomic_dec_and_test(&dev->open_count))
493 drm_lastclose(dev);
494
495 if (drm_dev_needs_global_mutex(dev))
496 mutex_unlock(&drm_global_mutex);
497
498 drm_minor_release(minor);
499
500 return 0;
501}
502EXPORT_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 */
519int drm_release_noglobal(struct inode *inode, struct file *filp)
520{
521 struct drm_file *file_priv = filp->private_data;
522 struct drm_minor *minor = file_priv->minor;
523 struct drm_device *dev = minor->dev;
524
525 drm_close_helper(filp);
526
527 if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) {
528 drm_lastclose(dev);
529 mutex_unlock(&drm_global_mutex);
530 }
531
532 drm_minor_release(minor);
533
534 return 0;
535}
536EXPORT_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 */
563ssize_t drm_read(struct file *filp, char __user *buffer,
564 size_t count, loff_t *offset)
565{
566 struct drm_file *file_priv = filp->private_data;
567 struct drm_device *dev = file_priv->minor->dev;
568 ssize_t ret;
569
570 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
571 if (ret)
572 return ret;
573
574 for (;;) {
575 struct drm_pending_event *e = NULL;
576
577 spin_lock_irq(&dev->event_lock);
578 if (!list_empty(&file_priv->event_list)) {
579 e = list_first_entry(&file_priv->event_list,
580 struct drm_pending_event, link);
581 file_priv->event_space += e->event->length;
582 list_del(&e->link);
583 }
584 spin_unlock_irq(&dev->event_lock);
585
586 if (e == NULL) {
587 if (ret)
588 break;
589
590 if (filp->f_flags & O_NONBLOCK) {
591 ret = -EAGAIN;
592 break;
593 }
594
595 mutex_unlock(&file_priv->event_read_lock);
596 ret = wait_event_interruptible(file_priv->event_wait,
597 !list_empty(&file_priv->event_list));
598 if (ret >= 0)
599 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
600 if (ret)
601 return ret;
602 } else {
603 unsigned length = e->event->length;
604
605 if (length > count - ret) {
606put_back_event:
607 spin_lock_irq(&dev->event_lock);
608 file_priv->event_space -= length;
609 list_add(&e->link, &file_priv->event_list);
610 spin_unlock_irq(&dev->event_lock);
611 wake_up_interruptible_poll(&file_priv->event_wait,
612 EPOLLIN | EPOLLRDNORM);
613 break;
614 }
615
616 if (copy_to_user(buffer + ret, e->event, length)) {
617 if (ret == 0)
618 ret = -EFAULT;
619 goto put_back_event;
620 }
621
622 ret += length;
623 kfree(e);
624 }
625 }
626 mutex_unlock(&file_priv->event_read_lock);
627
628 return ret;
629}
630EXPORT_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__poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
649{
650 struct drm_file *file_priv = filp->private_data;
651 __poll_t mask = 0;
652
653 poll_wait(filp, &file_priv->event_wait, wait);
654
655 if (!list_empty(&file_priv->event_list))
656 mask |= EPOLLIN | EPOLLRDNORM;
657
658 return mask;
659}
660EXPORT_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 */
686int 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 if (file_priv->event_space < e->length)
692 return -ENOMEM;
693
694 file_priv->event_space -= e->length;
695
696 p->event = e;
697 list_add(&p->pending_link, &file_priv->pending_event_list);
698 p->file_priv = file_priv;
699
700 return 0;
701}
702EXPORT_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 */
728int 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 spin_lock_irqsave(&dev->event_lock, flags);
737 ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
738 spin_unlock_irqrestore(&dev->event_lock, flags);
739
740 return ret;
741}
742EXPORT_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 */
753void drm_event_cancel_free(struct drm_device *dev,
754 struct drm_pending_event *p)
755{
756 unsigned long flags;
757
758 spin_lock_irqsave(&dev->event_lock, flags);
759 if (p->file_priv) {
760 p->file_priv->event_space += p->event->length;
761 list_del(&p->pending_link);
762 }
763 spin_unlock_irqrestore(&dev->event_lock, flags);
764
765 if (p->fence)
766 dma_fence_put(p->fence);
767
768 kfree(p);
769}
770EXPORT_SYMBOL(drm_event_cancel_free);
771
772static 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 if (e->completion) {
778 complete_all(e->completion);
779 e->completion_release(e->completion);
780 e->completion = NULL;
781 }
782
783 if (e->fence) {
784 if (timestamp)
785 dma_fence_signal_timestamp(e->fence, timestamp);
786 else
787 dma_fence_signal(e->fence);
788 dma_fence_put(e->fence);
789 }
790
791 if (!e->file_priv) {
792 kfree(e);
793 return;
794 }
795
796 list_del(&e->pending_link);
797 list_add_tail(&e->link,
798 &e->file_priv->event_list);
799 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 */
819void drm_send_event_timestamp_locked(struct drm_device *dev,
820 struct drm_pending_event *e, ktime_t timestamp)
821{
822 drm_send_event_helper(dev, e, timestamp);
823}
824EXPORT_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 */
840void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
841{
842 drm_send_event_helper(dev, e, 0);
843}
844EXPORT_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 */
861void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
862{
863 unsigned long irqflags;
864
865 spin_lock_irqsave(&dev->event_lock, irqflags);
866 drm_send_event_helper(dev, e, 0);
867 spin_unlock_irqrestore(&dev->event_lock, irqflags);
868}
869EXPORT_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 */
885struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
886{
887 struct drm_device *dev = minor->dev;
888 struct drm_file *priv;
889 struct file *file;
890
891 priv = drm_file_alloc(minor);
892 if (IS_ERR(priv))
893 return ERR_CAST(priv);
894
895 file = anon_inode_getfile("drm", dev->driver->fops, priv, flags);
896 if (IS_ERR(file)) {
897 drm_file_free(priv);
898 return file;
899 }
900
901 /* Everyone shares a single global address space */
902 file->f_mapping = dev->anon_inode->i_mapping;
903
904 drm_dev_get(dev);
905 priv->filp = file;
906
907 return file;
908}
909EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);