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_gem.h>
46#include <drm/drm_print.h>
47
48#include "drm_crtc_internal.h"
49#include "drm_internal.h"
50#include "drm_legacy.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 * Legacy drivers rely on all kinds of BKL locking semantics, don't
59 * bother. They also still need BKL locking for their ioctls, so better
60 * safe than sorry.
61 */
62 if (drm_core_check_feature(dev, feature: DRIVER_LEGACY))
63 return true;
64
65 /*
66 * The deprecated ->load callback must be called after the driver is
67 * already registered. This means such drivers rely on the BKL to make
68 * sure an open can't proceed until the driver is actually fully set up.
69 * Similar hilarity holds for the unload callback.
70 */
71 if (dev->driver->load || dev->driver->unload)
72 return true;
73
74 /*
75 * Drivers with the lastclose callback assume that it's synchronized
76 * against concurrent opens, which again needs the BKL. The proper fix
77 * is to use the drm_client infrastructure with proper locking for each
78 * client.
79 */
80 if (dev->driver->lastclose)
81 return true;
82
83 return false;
84}
85
86/**
87 * DOC: file operations
88 *
89 * Drivers must define the file operations structure that forms the DRM
90 * userspace API entry point, even though most of those operations are
91 * implemented in the DRM core. The resulting &struct file_operations must be
92 * stored in the &drm_driver.fops field. The mandatory functions are drm_open(),
93 * drm_read(), drm_ioctl() and drm_compat_ioctl() if CONFIG_COMPAT is enabled
94 * Note that drm_compat_ioctl will be NULL if CONFIG_COMPAT=n, so there's no
95 * need to sprinkle #ifdef into the code. Drivers which implement private ioctls
96 * that require 32/64 bit compatibility support must provide their own
97 * &file_operations.compat_ioctl handler that processes private ioctls and calls
98 * drm_compat_ioctl() for core ioctls.
99 *
100 * In addition drm_read() and drm_poll() provide support for DRM events. DRM
101 * events are a generic and extensible means to send asynchronous events to
102 * userspace through the file descriptor. They are used to send vblank event and
103 * page flip completions by the KMS API. But drivers can also use it for their
104 * own needs, e.g. to signal completion of rendering.
105 *
106 * For the driver-side event interface see drm_event_reserve_init() and
107 * drm_send_event() as the main starting points.
108 *
109 * The memory mapping implementation will vary depending on how the driver
110 * manages memory. Legacy drivers will use the deprecated drm_legacy_mmap()
111 * function, modern drivers should use one of the provided memory-manager
112 * specific implementations. For GEM-based drivers this is drm_gem_mmap().
113 *
114 * No other file operations are supported by the DRM userspace API. Overall the
115 * following is an example &file_operations structure::
116 *
117 * static const example_drm_fops = {
118 * .owner = THIS_MODULE,
119 * .open = drm_open,
120 * .release = drm_release,
121 * .unlocked_ioctl = drm_ioctl,
122 * .compat_ioctl = drm_compat_ioctl, // NULL if CONFIG_COMPAT=n
123 * .poll = drm_poll,
124 * .read = drm_read,
125 * .llseek = no_llseek,
126 * .mmap = drm_gem_mmap,
127 * };
128 *
129 * For plain GEM based drivers there is the DEFINE_DRM_GEM_FOPS() macro, and for
130 * DMA based drivers there is the DEFINE_DRM_GEM_DMA_FOPS() macro to make this
131 * simpler.
132 *
133 * The driver's &file_operations must be stored in &drm_driver.fops.
134 *
135 * For driver-private IOCTL handling see the more detailed discussion in
136 * :ref:`IOCTL support in the userland interfaces chapter<drm_driver_ioctl>`.
137 */
138
139/**
140 * drm_file_alloc - allocate file context
141 * @minor: minor to allocate on
142 *
143 * This allocates a new DRM file context. It is not linked into any context and
144 * can be used by the caller freely. Note that the context keeps a pointer to
145 * @minor, so it must be freed before @minor is.
146 *
147 * RETURNS:
148 * Pointer to newly allocated context, ERR_PTR on failure.
149 */
150struct drm_file *drm_file_alloc(struct drm_minor *minor)
151{
152 static atomic64_t ident = ATOMIC_INIT(0);
153 struct drm_device *dev = minor->dev;
154 struct drm_file *file;
155 int ret;
156
157 file = kzalloc(size: sizeof(*file), GFP_KERNEL);
158 if (!file)
159 return ERR_PTR(error: -ENOMEM);
160
161 /* Get a unique identifier for fdinfo: */
162 file->client_id = atomic64_inc_return(v: &ident);
163 rcu_assign_pointer(file->pid, get_pid(task_tgid(current)));
164 file->minor = minor;
165
166 /* for compatibility root is always authenticated */
167 file->authenticated = capable(CAP_SYS_ADMIN);
168
169 INIT_LIST_HEAD(list: &file->lhead);
170 INIT_LIST_HEAD(list: &file->fbs);
171 mutex_init(&file->fbs_lock);
172 INIT_LIST_HEAD(list: &file->blobs);
173 INIT_LIST_HEAD(list: &file->pending_event_list);
174 INIT_LIST_HEAD(list: &file->event_list);
175 init_waitqueue_head(&file->event_wait);
176 file->event_space = 4096; /* set aside 4k for event buffer */
177
178 spin_lock_init(&file->master_lookup_lock);
179 mutex_init(&file->event_read_lock);
180
181 if (drm_core_check_feature(dev, feature: DRIVER_GEM))
182 drm_gem_open(dev, file_private: file);
183
184 if (drm_core_check_feature(dev, feature: DRIVER_SYNCOBJ))
185 drm_syncobj_open(file_private: file);
186
187 drm_prime_init_file_private(prime_fpriv: &file->prime);
188
189 if (dev->driver->open) {
190 ret = dev->driver->open(dev, file);
191 if (ret < 0)
192 goto out_prime_destroy;
193 }
194
195 return file;
196
197out_prime_destroy:
198 drm_prime_destroy_file_private(prime_fpriv: &file->prime);
199 if (drm_core_check_feature(dev, feature: DRIVER_SYNCOBJ))
200 drm_syncobj_release(file_private: file);
201 if (drm_core_check_feature(dev, feature: DRIVER_GEM))
202 drm_gem_release(dev, file_private: file);
203 put_pid(rcu_access_pointer(file->pid));
204 kfree(objp: file);
205
206 return ERR_PTR(error: ret);
207}
208
209static void drm_events_release(struct drm_file *file_priv)
210{
211 struct drm_device *dev = file_priv->minor->dev;
212 struct drm_pending_event *e, *et;
213 unsigned long flags;
214
215 spin_lock_irqsave(&dev->event_lock, flags);
216
217 /* Unlink pending events */
218 list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
219 pending_link) {
220 list_del(entry: &e->pending_link);
221 e->file_priv = NULL;
222 }
223
224 /* Remove unconsumed events */
225 list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
226 list_del(entry: &e->link);
227 kfree(objp: e);
228 }
229
230 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
231}
232
233/**
234 * drm_file_free - free file context
235 * @file: context to free, or NULL
236 *
237 * This destroys and deallocates a DRM file context previously allocated via
238 * drm_file_alloc(). The caller must make sure to unlink it from any contexts
239 * before calling this.
240 *
241 * If NULL is passed, this is a no-op.
242 */
243void drm_file_free(struct drm_file *file)
244{
245 struct drm_device *dev;
246
247 if (!file)
248 return;
249
250 dev = file->minor->dev;
251
252 drm_dbg_core(dev, "comm=\"%s\", pid=%d, dev=0x%lx, open_count=%d\n",
253 current->comm, task_pid_nr(current),
254 (long)old_encode_dev(file->minor->kdev->devt),
255 atomic_read(&dev->open_count));
256
257#ifdef CONFIG_DRM_LEGACY
258 if (drm_core_check_feature(dev, feature: DRIVER_LEGACY) &&
259 dev->driver->preclose)
260 dev->driver->preclose(dev, file);
261#endif
262
263 if (drm_core_check_feature(dev, feature: DRIVER_LEGACY))
264 drm_legacy_lock_release(dev, filp: file->filp);
265
266 if (drm_core_check_feature(dev, feature: DRIVER_HAVE_DMA))
267 drm_legacy_reclaim_buffers(dev, filp: file);
268
269 drm_events_release(file_priv: file);
270
271 if (drm_core_check_feature(dev, feature: DRIVER_MODESET)) {
272 drm_fb_release(file_priv: file);
273 drm_property_destroy_user_blobs(dev, file_priv: file);
274 }
275
276 if (drm_core_check_feature(dev, feature: DRIVER_SYNCOBJ))
277 drm_syncobj_release(file_private: file);
278
279 if (drm_core_check_feature(dev, feature: DRIVER_GEM))
280 drm_gem_release(dev, file_private: file);
281
282 drm_legacy_ctxbitmap_flush(dev, file);
283
284 if (drm_is_primary_client(file_priv: file))
285 drm_master_release(file_priv: file);
286
287 if (dev->driver->postclose)
288 dev->driver->postclose(dev, file);
289
290 drm_prime_destroy_file_private(prime_fpriv: &file->prime);
291
292 WARN_ON(!list_empty(&file->event_list));
293
294 put_pid(rcu_access_pointer(file->pid));
295 kfree(objp: file);
296}
297
298static void drm_close_helper(struct file *filp)
299{
300 struct drm_file *file_priv = filp->private_data;
301 struct drm_device *dev = file_priv->minor->dev;
302
303 mutex_lock(&dev->filelist_mutex);
304 list_del(entry: &file_priv->lhead);
305 mutex_unlock(lock: &dev->filelist_mutex);
306
307 drm_file_free(file: file_priv);
308}
309
310/*
311 * Check whether DRI will run on this CPU.
312 *
313 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
314 */
315static int drm_cpu_valid(void)
316{
317#if defined(__sparc__) && !defined(__sparc_v9__)
318 return 0; /* No cmpxchg before v9 sparc. */
319#endif
320 return 1;
321}
322
323/*
324 * Called whenever a process opens a drm node
325 *
326 * \param filp file pointer.
327 * \param minor acquired minor-object.
328 * \return zero on success or a negative number on failure.
329 *
330 * Creates and initializes a drm_file structure for the file private data in \p
331 * filp and add it into the double linked list in \p dev.
332 */
333int drm_open_helper(struct file *filp, struct drm_minor *minor)
334{
335 struct drm_device *dev = minor->dev;
336 struct drm_file *priv;
337 int ret;
338
339 if (filp->f_flags & O_EXCL)
340 return -EBUSY; /* No exclusive opens */
341 if (!drm_cpu_valid())
342 return -EINVAL;
343 if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
344 dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
345 return -EINVAL;
346
347 drm_dbg_core(dev, "comm=\"%s\", pid=%d, minor=%d\n",
348 current->comm, task_pid_nr(current), minor->index);
349
350 priv = drm_file_alloc(minor);
351 if (IS_ERR(ptr: priv))
352 return PTR_ERR(ptr: priv);
353
354 if (drm_is_primary_client(file_priv: priv)) {
355 ret = drm_master_open(file_priv: priv);
356 if (ret) {
357 drm_file_free(file: priv);
358 return ret;
359 }
360 }
361
362 filp->private_data = priv;
363 filp->f_mode |= FMODE_UNSIGNED_OFFSET;
364 priv->filp = filp;
365
366 mutex_lock(&dev->filelist_mutex);
367 list_add(new: &priv->lhead, head: &dev->filelist);
368 mutex_unlock(lock: &dev->filelist_mutex);
369
370#ifdef CONFIG_DRM_LEGACY
371#ifdef __alpha__
372 /*
373 * Default the hose
374 */
375 if (!dev->hose) {
376 struct pci_dev *pci_dev;
377
378 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
379 if (pci_dev) {
380 dev->hose = pci_dev->sysdata;
381 pci_dev_put(pci_dev);
382 }
383 if (!dev->hose) {
384 struct pci_bus *b = list_entry(pci_root_buses.next,
385 struct pci_bus, node);
386 if (b)
387 dev->hose = b->sysdata;
388 }
389 }
390#endif
391#endif
392
393 return 0;
394}
395
396/**
397 * drm_open - open method for DRM file
398 * @inode: device inode
399 * @filp: file pointer.
400 *
401 * This function must be used by drivers as their &file_operations.open method.
402 * It looks up the correct DRM device and instantiates all the per-file
403 * resources for it. It also calls the &drm_driver.open driver callback.
404 *
405 * RETURNS:
406 *
407 * 0 on success or negative errno value on failure.
408 */
409int drm_open(struct inode *inode, struct file *filp)
410{
411 struct drm_device *dev;
412 struct drm_minor *minor;
413 int retcode;
414 int need_setup = 0;
415
416 minor = drm_minor_acquire(minor_id: iminor(inode));
417 if (IS_ERR(ptr: minor))
418 return PTR_ERR(ptr: minor);
419
420 dev = minor->dev;
421 if (drm_dev_needs_global_mutex(dev))
422 mutex_lock(&drm_global_mutex);
423
424 if (!atomic_fetch_inc(v: &dev->open_count))
425 need_setup = 1;
426
427 /* share address_space across all char-devs of a single device */
428 filp->f_mapping = dev->anon_inode->i_mapping;
429
430 retcode = drm_open_helper(filp, minor);
431 if (retcode)
432 goto err_undo;
433 if (need_setup) {
434 retcode = drm_legacy_setup(dev);
435 if (retcode) {
436 drm_close_helper(filp);
437 goto err_undo;
438 }
439 }
440
441 if (drm_dev_needs_global_mutex(dev))
442 mutex_unlock(lock: &drm_global_mutex);
443
444 return 0;
445
446err_undo:
447 atomic_dec(v: &dev->open_count);
448 if (drm_dev_needs_global_mutex(dev))
449 mutex_unlock(lock: &drm_global_mutex);
450 drm_minor_release(minor);
451 return retcode;
452}
453EXPORT_SYMBOL(drm_open);
454
455void drm_lastclose(struct drm_device * dev)
456{
457 drm_dbg_core(dev, "\n");
458
459 if (dev->driver->lastclose)
460 dev->driver->lastclose(dev);
461 drm_dbg_core(dev, "driver lastclose completed\n");
462
463 if (drm_core_check_feature(dev, feature: DRIVER_LEGACY))
464 drm_legacy_dev_reinit(dev);
465
466 drm_client_dev_restore(dev);
467}
468
469/**
470 * drm_release - release method for DRM file
471 * @inode: device inode
472 * @filp: file pointer.
473 *
474 * This function must be used by drivers as their &file_operations.release
475 * method. It frees any resources associated with the open file, and calls the
476 * &drm_driver.postclose driver callback. If this is the last open file for the
477 * DRM device also proceeds to call the &drm_driver.lastclose driver callback.
478 *
479 * RETURNS:
480 *
481 * Always succeeds and returns 0.
482 */
483int drm_release(struct inode *inode, struct file *filp)
484{
485 struct drm_file *file_priv = filp->private_data;
486 struct drm_minor *minor = file_priv->minor;
487 struct drm_device *dev = minor->dev;
488
489 if (drm_dev_needs_global_mutex(dev))
490 mutex_lock(&drm_global_mutex);
491
492 drm_dbg_core(dev, "open_count = %d\n", atomic_read(&dev->open_count));
493
494 drm_close_helper(filp);
495
496 if (atomic_dec_and_test(v: &dev->open_count))
497 drm_lastclose(dev);
498
499 if (drm_dev_needs_global_mutex(dev))
500 mutex_unlock(lock: &drm_global_mutex);
501
502 drm_minor_release(minor);
503
504 return 0;
505}
506EXPORT_SYMBOL(drm_release);
507
508void drm_file_update_pid(struct drm_file *filp)
509{
510 struct drm_device *dev;
511 struct pid *pid, *old;
512
513 /*
514 * Master nodes need to keep the original ownership in order for
515 * drm_master_check_perm to keep working correctly. (See comment in
516 * drm_auth.c.)
517 */
518 if (filp->was_master)
519 return;
520
521 pid = task_tgid(current);
522
523 /*
524 * Quick unlocked check since the model is a single handover followed by
525 * exclusive repeated use.
526 */
527 if (pid == rcu_access_pointer(filp->pid))
528 return;
529
530 dev = filp->minor->dev;
531 mutex_lock(&dev->filelist_mutex);
532 old = rcu_replace_pointer(filp->pid, pid, 1);
533 mutex_unlock(lock: &dev->filelist_mutex);
534
535 if (pid != old) {
536 get_pid(pid);
537 synchronize_rcu();
538 put_pid(pid: old);
539 }
540}
541
542/**
543 * drm_release_noglobal - release method for DRM file
544 * @inode: device inode
545 * @filp: file pointer.
546 *
547 * This function may be used by drivers as their &file_operations.release
548 * method. It frees any resources associated with the open file prior to taking
549 * the drm_global_mutex, which then calls the &drm_driver.postclose driver
550 * callback. If this is the last open file for the DRM device also proceeds to
551 * call the &drm_driver.lastclose driver callback.
552 *
553 * RETURNS:
554 *
555 * Always succeeds and returns 0.
556 */
557int drm_release_noglobal(struct inode *inode, struct file *filp)
558{
559 struct drm_file *file_priv = filp->private_data;
560 struct drm_minor *minor = file_priv->minor;
561 struct drm_device *dev = minor->dev;
562
563 drm_close_helper(filp);
564
565 if (atomic_dec_and_mutex_lock(cnt: &dev->open_count, lock: &drm_global_mutex)) {
566 drm_lastclose(dev);
567 mutex_unlock(lock: &drm_global_mutex);
568 }
569
570 drm_minor_release(minor);
571
572 return 0;
573}
574EXPORT_SYMBOL(drm_release_noglobal);
575
576/**
577 * drm_read - read method for DRM file
578 * @filp: file pointer
579 * @buffer: userspace destination pointer for the read
580 * @count: count in bytes to read
581 * @offset: offset to read
582 *
583 * This function must be used by drivers as their &file_operations.read
584 * method if they use DRM events for asynchronous signalling to userspace.
585 * Since events are used by the KMS API for vblank and page flip completion this
586 * means all modern display drivers must use it.
587 *
588 * @offset is ignored, DRM events are read like a pipe. Polling support is
589 * provided by drm_poll().
590 *
591 * This function will only ever read a full event. Therefore userspace must
592 * supply a big enough buffer to fit any event to ensure forward progress. Since
593 * the maximum event space is currently 4K it's recommended to just use that for
594 * safety.
595 *
596 * RETURNS:
597 *
598 * Number of bytes read (always aligned to full events, and can be 0) or a
599 * negative error code on failure.
600 */
601ssize_t drm_read(struct file *filp, char __user *buffer,
602 size_t count, loff_t *offset)
603{
604 struct drm_file *file_priv = filp->private_data;
605 struct drm_device *dev = file_priv->minor->dev;
606 ssize_t ret;
607
608 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
609 if (ret)
610 return ret;
611
612 for (;;) {
613 struct drm_pending_event *e = NULL;
614
615 spin_lock_irq(lock: &dev->event_lock);
616 if (!list_empty(head: &file_priv->event_list)) {
617 e = list_first_entry(&file_priv->event_list,
618 struct drm_pending_event, link);
619 file_priv->event_space += e->event->length;
620 list_del(entry: &e->link);
621 }
622 spin_unlock_irq(lock: &dev->event_lock);
623
624 if (e == NULL) {
625 if (ret)
626 break;
627
628 if (filp->f_flags & O_NONBLOCK) {
629 ret = -EAGAIN;
630 break;
631 }
632
633 mutex_unlock(lock: &file_priv->event_read_lock);
634 ret = wait_event_interruptible(file_priv->event_wait,
635 !list_empty(&file_priv->event_list));
636 if (ret >= 0)
637 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
638 if (ret)
639 return ret;
640 } else {
641 unsigned length = e->event->length;
642
643 if (length > count - ret) {
644put_back_event:
645 spin_lock_irq(lock: &dev->event_lock);
646 file_priv->event_space -= length;
647 list_add(new: &e->link, head: &file_priv->event_list);
648 spin_unlock_irq(lock: &dev->event_lock);
649 wake_up_interruptible_poll(&file_priv->event_wait,
650 EPOLLIN | EPOLLRDNORM);
651 break;
652 }
653
654 if (copy_to_user(to: buffer + ret, from: e->event, n: length)) {
655 if (ret == 0)
656 ret = -EFAULT;
657 goto put_back_event;
658 }
659
660 ret += length;
661 kfree(objp: e);
662 }
663 }
664 mutex_unlock(lock: &file_priv->event_read_lock);
665
666 return ret;
667}
668EXPORT_SYMBOL(drm_read);
669
670/**
671 * drm_poll - poll method for DRM file
672 * @filp: file pointer
673 * @wait: poll waiter table
674 *
675 * This function must be used by drivers as their &file_operations.read method
676 * if they use DRM events for asynchronous signalling to userspace. Since
677 * events are used by the KMS API for vblank and page flip completion this means
678 * all modern display drivers must use it.
679 *
680 * See also drm_read().
681 *
682 * RETURNS:
683 *
684 * Mask of POLL flags indicating the current status of the file.
685 */
686__poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
687{
688 struct drm_file *file_priv = filp->private_data;
689 __poll_t mask = 0;
690
691 poll_wait(filp, wait_address: &file_priv->event_wait, p: wait);
692
693 if (!list_empty(head: &file_priv->event_list))
694 mask |= EPOLLIN | EPOLLRDNORM;
695
696 return mask;
697}
698EXPORT_SYMBOL(drm_poll);
699
700/**
701 * drm_event_reserve_init_locked - init a DRM event and reserve space for it
702 * @dev: DRM device
703 * @file_priv: DRM file private data
704 * @p: tracking structure for the pending event
705 * @e: actual event data to deliver to userspace
706 *
707 * This function prepares the passed in event for eventual delivery. If the event
708 * doesn't get delivered (because the IOCTL fails later on, before queuing up
709 * anything) then the even must be cancelled and freed using
710 * drm_event_cancel_free(). Successfully initialized events should be sent out
711 * using drm_send_event() or drm_send_event_locked() to signal completion of the
712 * asynchronous event to userspace.
713 *
714 * If callers embedded @p into a larger structure it must be allocated with
715 * kmalloc and @p must be the first member element.
716 *
717 * This is the locked version of drm_event_reserve_init() for callers which
718 * already hold &drm_device.event_lock.
719 *
720 * RETURNS:
721 *
722 * 0 on success or a negative error code on failure.
723 */
724int drm_event_reserve_init_locked(struct drm_device *dev,
725 struct drm_file *file_priv,
726 struct drm_pending_event *p,
727 struct drm_event *e)
728{
729 if (file_priv->event_space < e->length)
730 return -ENOMEM;
731
732 file_priv->event_space -= e->length;
733
734 p->event = e;
735 list_add(new: &p->pending_link, head: &file_priv->pending_event_list);
736 p->file_priv = file_priv;
737
738 return 0;
739}
740EXPORT_SYMBOL(drm_event_reserve_init_locked);
741
742/**
743 * drm_event_reserve_init - init a DRM event and reserve space for it
744 * @dev: DRM device
745 * @file_priv: DRM file private data
746 * @p: tracking structure for the pending event
747 * @e: actual event data to deliver to userspace
748 *
749 * This function prepares the passed in event for eventual delivery. If the event
750 * doesn't get delivered (because the IOCTL fails later on, before queuing up
751 * anything) then the even must be cancelled and freed using
752 * drm_event_cancel_free(). Successfully initialized events should be sent out
753 * using drm_send_event() or drm_send_event_locked() to signal completion of the
754 * asynchronous event to userspace.
755 *
756 * If callers embedded @p into a larger structure it must be allocated with
757 * kmalloc and @p must be the first member element.
758 *
759 * Callers which already hold &drm_device.event_lock should use
760 * drm_event_reserve_init_locked() instead.
761 *
762 * RETURNS:
763 *
764 * 0 on success or a negative error code on failure.
765 */
766int drm_event_reserve_init(struct drm_device *dev,
767 struct drm_file *file_priv,
768 struct drm_pending_event *p,
769 struct drm_event *e)
770{
771 unsigned long flags;
772 int ret;
773
774 spin_lock_irqsave(&dev->event_lock, flags);
775 ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
776 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
777
778 return ret;
779}
780EXPORT_SYMBOL(drm_event_reserve_init);
781
782/**
783 * drm_event_cancel_free - free a DRM event and release its space
784 * @dev: DRM device
785 * @p: tracking structure for the pending event
786 *
787 * This function frees the event @p initialized with drm_event_reserve_init()
788 * and releases any allocated space. It is used to cancel an event when the
789 * nonblocking operation could not be submitted and needed to be aborted.
790 */
791void drm_event_cancel_free(struct drm_device *dev,
792 struct drm_pending_event *p)
793{
794 unsigned long flags;
795
796 spin_lock_irqsave(&dev->event_lock, flags);
797 if (p->file_priv) {
798 p->file_priv->event_space += p->event->length;
799 list_del(entry: &p->pending_link);
800 }
801 spin_unlock_irqrestore(lock: &dev->event_lock, flags);
802
803 if (p->fence)
804 dma_fence_put(fence: p->fence);
805
806 kfree(objp: p);
807}
808EXPORT_SYMBOL(drm_event_cancel_free);
809
810static void drm_send_event_helper(struct drm_device *dev,
811 struct drm_pending_event *e, ktime_t timestamp)
812{
813 assert_spin_locked(&dev->event_lock);
814
815 if (e->completion) {
816 complete_all(e->completion);
817 e->completion_release(e->completion);
818 e->completion = NULL;
819 }
820
821 if (e->fence) {
822 if (timestamp)
823 dma_fence_signal_timestamp(fence: e->fence, timestamp);
824 else
825 dma_fence_signal(fence: e->fence);
826 dma_fence_put(fence: e->fence);
827 }
828
829 if (!e->file_priv) {
830 kfree(objp: e);
831 return;
832 }
833
834 list_del(entry: &e->pending_link);
835 list_add_tail(new: &e->link,
836 head: &e->file_priv->event_list);
837 wake_up_interruptible_poll(&e->file_priv->event_wait,
838 EPOLLIN | EPOLLRDNORM);
839}
840
841/**
842 * drm_send_event_timestamp_locked - send DRM event to file descriptor
843 * @dev: DRM device
844 * @e: DRM event to deliver
845 * @timestamp: timestamp to set for the fence event in kernel's CLOCK_MONOTONIC
846 * time domain
847 *
848 * This function sends the event @e, initialized with drm_event_reserve_init(),
849 * to its associated userspace DRM file. Callers must already hold
850 * &drm_device.event_lock.
851 *
852 * Note that the core will take care of unlinking and disarming events when the
853 * corresponding DRM file is closed. Drivers need not worry about whether the
854 * DRM file for this event still exists and can call this function upon
855 * completion of the asynchronous work unconditionally.
856 */
857void drm_send_event_timestamp_locked(struct drm_device *dev,
858 struct drm_pending_event *e, ktime_t timestamp)
859{
860 drm_send_event_helper(dev, e, timestamp);
861}
862EXPORT_SYMBOL(drm_send_event_timestamp_locked);
863
864/**
865 * drm_send_event_locked - send DRM event to file descriptor
866 * @dev: DRM device
867 * @e: DRM event to deliver
868 *
869 * This function sends the event @e, initialized with drm_event_reserve_init(),
870 * to its associated userspace DRM file. Callers must already hold
871 * &drm_device.event_lock, see drm_send_event() for the unlocked version.
872 *
873 * Note that the core will take care of unlinking and disarming events when the
874 * corresponding DRM file is closed. Drivers need not worry about whether the
875 * DRM file for this event still exists and can call this function upon
876 * completion of the asynchronous work unconditionally.
877 */
878void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
879{
880 drm_send_event_helper(dev, e, timestamp: 0);
881}
882EXPORT_SYMBOL(drm_send_event_locked);
883
884/**
885 * drm_send_event - send DRM event to file descriptor
886 * @dev: DRM device
887 * @e: DRM event to deliver
888 *
889 * This function sends the event @e, initialized with drm_event_reserve_init(),
890 * to its associated userspace DRM file. This function acquires
891 * &drm_device.event_lock, see drm_send_event_locked() for callers which already
892 * hold this lock.
893 *
894 * Note that the core will take care of unlinking and disarming events when the
895 * corresponding DRM file is closed. Drivers need not worry about whether the
896 * DRM file for this event still exists and can call this function upon
897 * completion of the asynchronous work unconditionally.
898 */
899void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
900{
901 unsigned long irqflags;
902
903 spin_lock_irqsave(&dev->event_lock, irqflags);
904 drm_send_event_helper(dev, e, timestamp: 0);
905 spin_unlock_irqrestore(lock: &dev->event_lock, flags: irqflags);
906}
907EXPORT_SYMBOL(drm_send_event);
908
909static void print_size(struct drm_printer *p, const char *stat,
910 const char *region, u64 sz)
911{
912 const char *units[] = {"", " KiB", " MiB"};
913 unsigned u;
914
915 for (u = 0; u < ARRAY_SIZE(units) - 1; u++) {
916 if (sz < SZ_1K)
917 break;
918 sz = div_u64(dividend: sz, SZ_1K);
919 }
920
921 drm_printf(p, f: "drm-%s-%s:\t%llu%s\n", stat, region, sz, units[u]);
922}
923
924/**
925 * drm_print_memory_stats - A helper to print memory stats
926 * @p: The printer to print output to
927 * @stats: The collected memory stats
928 * @supported_status: Bitmask of optional stats which are available
929 * @region: The memory region
930 *
931 */
932void drm_print_memory_stats(struct drm_printer *p,
933 const struct drm_memory_stats *stats,
934 enum drm_gem_object_status supported_status,
935 const char *region)
936{
937 print_size(p, stat: "total", region, sz: stats->private + stats->shared);
938 print_size(p, stat: "shared", region, sz: stats->shared);
939 print_size(p, stat: "active", region, sz: stats->active);
940
941 if (supported_status & DRM_GEM_OBJECT_RESIDENT)
942 print_size(p, stat: "resident", region, sz: stats->resident);
943
944 if (supported_status & DRM_GEM_OBJECT_PURGEABLE)
945 print_size(p, stat: "purgeable", region, sz: stats->purgeable);
946}
947EXPORT_SYMBOL(drm_print_memory_stats);
948
949/**
950 * drm_show_memory_stats - Helper to collect and show standard fdinfo memory stats
951 * @p: the printer to print output to
952 * @file: the DRM file
953 *
954 * Helper to iterate over GEM objects with a handle allocated in the specified
955 * file.
956 */
957void drm_show_memory_stats(struct drm_printer *p, struct drm_file *file)
958{
959 struct drm_gem_object *obj;
960 struct drm_memory_stats status = {};
961 enum drm_gem_object_status supported_status;
962 int id;
963
964 spin_lock(lock: &file->table_lock);
965 idr_for_each_entry (&file->object_idr, obj, id) {
966 enum drm_gem_object_status s = 0;
967 size_t add_size = (obj->funcs && obj->funcs->rss) ?
968 obj->funcs->rss(obj) : obj->size;
969
970 if (obj->funcs && obj->funcs->status) {
971 s = obj->funcs->status(obj);
972 supported_status = DRM_GEM_OBJECT_RESIDENT |
973 DRM_GEM_OBJECT_PURGEABLE;
974 }
975
976 if (obj->handle_count > 1) {
977 status.shared += obj->size;
978 } else {
979 status.private += obj->size;
980 }
981
982 if (s & DRM_GEM_OBJECT_RESIDENT) {
983 status.resident += add_size;
984 } else {
985 /* If already purged or not yet backed by pages, don't
986 * count it as purgeable:
987 */
988 s &= ~DRM_GEM_OBJECT_PURGEABLE;
989 }
990
991 if (!dma_resv_test_signaled(obj: obj->resv, usage: dma_resv_usage_rw(write: true))) {
992 status.active += add_size;
993
994 /* If still active, don't count as purgeable: */
995 s &= ~DRM_GEM_OBJECT_PURGEABLE;
996 }
997
998 if (s & DRM_GEM_OBJECT_PURGEABLE)
999 status.purgeable += add_size;
1000 }
1001 spin_unlock(lock: &file->table_lock);
1002
1003 drm_print_memory_stats(p, &status, supported_status, "memory");
1004}
1005EXPORT_SYMBOL(drm_show_memory_stats);
1006
1007/**
1008 * drm_show_fdinfo - helper for drm file fops
1009 * @m: output stream
1010 * @f: the device file instance
1011 *
1012 * Helper to implement fdinfo, for userspace to query usage stats, etc, of a
1013 * process using the GPU. See also &drm_driver.show_fdinfo.
1014 *
1015 * For text output format description please see Documentation/gpu/drm-usage-stats.rst
1016 */
1017void drm_show_fdinfo(struct seq_file *m, struct file *f)
1018{
1019 struct drm_file *file = f->private_data;
1020 struct drm_device *dev = file->minor->dev;
1021 struct drm_printer p = drm_seq_file_printer(f: m);
1022
1023 drm_printf(p: &p, f: "drm-driver:\t%s\n", dev->driver->name);
1024 drm_printf(p: &p, f: "drm-client-id:\t%llu\n", file->client_id);
1025
1026 if (dev_is_pci(dev->dev)) {
1027 struct pci_dev *pdev = to_pci_dev(dev->dev);
1028
1029 drm_printf(p: &p, f: "drm-pdev:\t%04x:%02x:%02x.%d\n",
1030 pci_domain_nr(bus: pdev->bus), pdev->bus->number,
1031 PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
1032 }
1033
1034 if (dev->driver->show_fdinfo)
1035 dev->driver->show_fdinfo(&p, file);
1036}
1037EXPORT_SYMBOL(drm_show_fdinfo);
1038
1039/**
1040 * mock_drm_getfile - Create a new struct file for the drm device
1041 * @minor: drm minor to wrap (e.g. #drm_device.primary)
1042 * @flags: file creation mode (O_RDWR etc)
1043 *
1044 * This create a new struct file that wraps a DRM file context around a
1045 * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without
1046 * invoking userspace. The struct file may be operated on using its f_op
1047 * (the drm_device.driver.fops) to mimick userspace operations, or be supplied
1048 * to userspace facing functions as an internal/anonymous client.
1049 *
1050 * RETURNS:
1051 * Pointer to newly created struct file, ERR_PTR on failure.
1052 */
1053struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
1054{
1055 struct drm_device *dev = minor->dev;
1056 struct drm_file *priv;
1057 struct file *file;
1058
1059 priv = drm_file_alloc(minor);
1060 if (IS_ERR(ptr: priv))
1061 return ERR_CAST(ptr: priv);
1062
1063 file = anon_inode_getfile(name: "drm", fops: dev->driver->fops, priv, flags);
1064 if (IS_ERR(ptr: file)) {
1065 drm_file_free(file: priv);
1066 return file;
1067 }
1068
1069 /* Everyone shares a single global address space */
1070 file->f_mapping = dev->anon_inode->i_mapping;
1071
1072 drm_dev_get(dev);
1073 priv->filp = file;
1074
1075 return file;
1076}
1077EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
1078

source code of linux/drivers/gpu/drm/drm_file.c