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 #if defined(CONFIG_MMU) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
52 #include <uapi/asm/mman.h>
53 #include <drm/drm_vma_manager.h>
54 #endif
55
56 /* from BKL pushdown */
57 DEFINE_MUTEX(drm_global_mutex);
58
drm_dev_needs_global_mutex(struct drm_device * dev)59 bool drm_dev_needs_global_mutex(struct drm_device *dev)
60 {
61 /*
62 * Legacy drivers rely on all kinds of BKL locking semantics, don't
63 * bother. They also still need BKL locking for their ioctls, so better
64 * safe than sorry.
65 */
66 if (drm_core_check_feature(dev, DRIVER_LEGACY))
67 return true;
68
69 /*
70 * The deprecated ->load callback must be called after the driver is
71 * already registered. This means such drivers rely on the BKL to make
72 * sure an open can't proceed until the driver is actually fully set up.
73 * Similar hilarity holds for the unload callback.
74 */
75 if (dev->driver->load || dev->driver->unload)
76 return true;
77
78 /*
79 * Drivers with the lastclose callback assume that it's synchronized
80 * against concurrent opens, which again needs the BKL. The proper fix
81 * is to use the drm_client infrastructure with proper locking for each
82 * client.
83 */
84 if (dev->driver->lastclose)
85 return true;
86
87 return false;
88 }
89
90 /**
91 * DOC: file operations
92 *
93 * Drivers must define the file operations structure that forms the DRM
94 * userspace API entry point, even though most of those operations are
95 * implemented in the DRM core. The resulting &struct file_operations must be
96 * stored in the &drm_driver.fops field. The mandatory functions are drm_open(),
97 * drm_read(), drm_ioctl() and drm_compat_ioctl() if CONFIG_COMPAT is enabled
98 * Note that drm_compat_ioctl will be NULL if CONFIG_COMPAT=n, so there's no
99 * need to sprinkle #ifdef into the code. Drivers which implement private ioctls
100 * that require 32/64 bit compatibility support must provide their own
101 * &file_operations.compat_ioctl handler that processes private ioctls and calls
102 * drm_compat_ioctl() for core ioctls.
103 *
104 * In addition drm_read() and drm_poll() provide support for DRM events. DRM
105 * events are a generic and extensible means to send asynchronous events to
106 * userspace through the file descriptor. They are used to send vblank event and
107 * page flip completions by the KMS API. But drivers can also use it for their
108 * own needs, e.g. to signal completion of rendering.
109 *
110 * For the driver-side event interface see drm_event_reserve_init() and
111 * drm_send_event() as the main starting points.
112 *
113 * The memory mapping implementation will vary depending on how the driver
114 * manages memory. Legacy drivers will use the deprecated drm_legacy_mmap()
115 * function, modern drivers should use one of the provided memory-manager
116 * specific implementations. For GEM-based drivers this is drm_gem_mmap(), and
117 * for drivers which use the CMA GEM helpers it's drm_gem_cma_mmap().
118 *
119 * No other file operations are supported by the DRM userspace API. Overall the
120 * following is an example &file_operations structure::
121 *
122 * static const example_drm_fops = {
123 * .owner = THIS_MODULE,
124 * .open = drm_open,
125 * .release = drm_release,
126 * .unlocked_ioctl = drm_ioctl,
127 * .compat_ioctl = drm_compat_ioctl, // NULL if CONFIG_COMPAT=n
128 * .poll = drm_poll,
129 * .read = drm_read,
130 * .llseek = no_llseek,
131 * .mmap = drm_gem_mmap,
132 * };
133 *
134 * For plain GEM based drivers there is the DEFINE_DRM_GEM_FOPS() macro, and for
135 * CMA based drivers there is the DEFINE_DRM_GEM_CMA_FOPS() macro to make this
136 * simpler.
137 *
138 * The driver's &file_operations must be stored in &drm_driver.fops.
139 *
140 * For driver-private IOCTL handling see the more detailed discussion in
141 * :ref:`IOCTL support in the userland interfaces chapter<drm_driver_ioctl>`.
142 */
143
144 /**
145 * drm_file_alloc - allocate file context
146 * @minor: minor to allocate on
147 *
148 * This allocates a new DRM file context. It is not linked into any context and
149 * can be used by the caller freely. Note that the context keeps a pointer to
150 * @minor, so it must be freed before @minor is.
151 *
152 * RETURNS:
153 * Pointer to newly allocated context, ERR_PTR on failure.
154 */
drm_file_alloc(struct drm_minor * minor)155 struct drm_file *drm_file_alloc(struct drm_minor *minor)
156 {
157 struct drm_device *dev = minor->dev;
158 struct drm_file *file;
159 int ret;
160
161 file = kzalloc(sizeof(*file), GFP_KERNEL);
162 if (!file)
163 return ERR_PTR(-ENOMEM);
164
165 file->pid = get_pid(task_pid(current));
166 file->minor = minor;
167
168 /* for compatibility root is always authenticated */
169 file->authenticated = capable(CAP_SYS_ADMIN);
170
171 INIT_LIST_HEAD(&file->lhead);
172 INIT_LIST_HEAD(&file->fbs);
173 mutex_init(&file->fbs_lock);
174 INIT_LIST_HEAD(&file->blobs);
175 INIT_LIST_HEAD(&file->pending_event_list);
176 INIT_LIST_HEAD(&file->event_list);
177 init_waitqueue_head(&file->event_wait);
178 file->event_space = 4096; /* set aside 4k for event buffer */
179
180 mutex_init(&file->event_read_lock);
181
182 if (drm_core_check_feature(dev, DRIVER_GEM))
183 drm_gem_open(dev, file);
184
185 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
186 drm_syncobj_open(file);
187
188 drm_prime_init_file_private(&file->prime);
189
190 if (dev->driver->open) {
191 ret = dev->driver->open(dev, file);
192 if (ret < 0)
193 goto out_prime_destroy;
194 }
195
196 return file;
197
198 out_prime_destroy:
199 drm_prime_destroy_file_private(&file->prime);
200 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
201 drm_syncobj_release(file);
202 if (drm_core_check_feature(dev, DRIVER_GEM))
203 drm_gem_release(dev, file);
204 put_pid(file->pid);
205 kfree(file);
206
207 return ERR_PTR(ret);
208 }
209
drm_events_release(struct drm_file * file_priv)210 static void drm_events_release(struct drm_file *file_priv)
211 {
212 struct drm_device *dev = file_priv->minor->dev;
213 struct drm_pending_event *e, *et;
214 unsigned long flags;
215
216 spin_lock_irqsave(&dev->event_lock, flags);
217
218 /* Unlink pending events */
219 list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
220 pending_link) {
221 list_del(&e->pending_link);
222 e->file_priv = NULL;
223 }
224
225 /* Remove unconsumed events */
226 list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
227 list_del(&e->link);
228 kfree(e);
229 }
230
231 spin_unlock_irqrestore(&dev->event_lock, flags);
232 }
233
234 /**
235 * drm_file_free - free file context
236 * @file: context to free, or NULL
237 *
238 * This destroys and deallocates a DRM file context previously allocated via
239 * drm_file_alloc(). The caller must make sure to unlink it from any contexts
240 * before calling this.
241 *
242 * If NULL is passed, this is a no-op.
243 *
244 * RETURNS:
245 * 0 on success, or error code on failure.
246 */
drm_file_free(struct drm_file * file)247 void drm_file_free(struct drm_file *file)
248 {
249 struct drm_device *dev;
250
251 if (!file)
252 return;
253
254 dev = file->minor->dev;
255
256 DRM_DEBUG("comm=\"%s\", pid=%d, dev=0x%lx, open_count=%d\n",
257 current->comm, task_pid_nr(current),
258 (long)old_encode_dev(file->minor->kdev->devt),
259 atomic_read(&dev->open_count));
260
261 if (drm_core_check_feature(dev, DRIVER_LEGACY) &&
262 dev->driver->preclose)
263 dev->driver->preclose(dev, file);
264
265 if (drm_core_check_feature(dev, DRIVER_LEGACY))
266 drm_legacy_lock_release(dev, file->filp);
267
268 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
269 drm_legacy_reclaim_buffers(dev, file);
270
271 drm_events_release(file);
272
273 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
274 drm_fb_release(file);
275 drm_property_destroy_user_blobs(dev, file);
276 }
277
278 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
279 drm_syncobj_release(file);
280
281 if (drm_core_check_feature(dev, DRIVER_GEM))
282 drm_gem_release(dev, file);
283
284 drm_legacy_ctxbitmap_flush(dev, file);
285
286 if (drm_is_primary_client(file))
287 drm_master_release(file);
288
289 if (dev->driver->postclose)
290 dev->driver->postclose(dev, file);
291
292 drm_prime_destroy_file_private(&file->prime);
293
294 WARN_ON(!list_empty(&file->event_list));
295
296 put_pid(file->pid);
297 kfree(file);
298 }
299
drm_close_helper(struct file * filp)300 static void drm_close_helper(struct file *filp)
301 {
302 struct drm_file *file_priv = filp->private_data;
303 struct drm_device *dev = file_priv->minor->dev;
304
305 mutex_lock(&dev->filelist_mutex);
306 list_del(&file_priv->lhead);
307 mutex_unlock(&dev->filelist_mutex);
308
309 drm_file_free(file_priv);
310 }
311
312 /*
313 * Check whether DRI will run on this CPU.
314 *
315 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
316 */
drm_cpu_valid(void)317 static int drm_cpu_valid(void)
318 {
319 #if defined(__sparc__) && !defined(__sparc_v9__)
320 return 0; /* No cmpxchg before v9 sparc. */
321 #endif
322 return 1;
323 }
324
325 /*
326 * Called whenever a process opens a drm node
327 *
328 * \param filp file pointer.
329 * \param minor acquired minor-object.
330 * \return zero on success or a negative number on failure.
331 *
332 * Creates and initializes a drm_file structure for the file private data in \p
333 * filp and add it into the double linked list in \p dev.
334 */
drm_open_helper(struct file * filp,struct drm_minor * minor)335 static int drm_open_helper(struct file *filp, struct drm_minor *minor)
336 {
337 struct drm_device *dev = minor->dev;
338 struct drm_file *priv;
339 int ret;
340
341 if (filp->f_flags & O_EXCL)
342 return -EBUSY; /* No exclusive opens */
343 if (!drm_cpu_valid())
344 return -EINVAL;
345 if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
346 dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
347 return -EINVAL;
348
349 DRM_DEBUG("comm=\"%s\", pid=%d, minor=%d\n", current->comm,
350 task_pid_nr(current), minor->index);
351
352 priv = drm_file_alloc(minor);
353 if (IS_ERR(priv))
354 return PTR_ERR(priv);
355
356 if (drm_is_primary_client(priv)) {
357 ret = drm_master_open(priv);
358 if (ret) {
359 drm_file_free(priv);
360 return ret;
361 }
362 }
363
364 filp->private_data = priv;
365 filp->f_mode |= FMODE_UNSIGNED_OFFSET;
366 priv->filp = filp;
367
368 mutex_lock(&dev->filelist_mutex);
369 list_add(&priv->lhead, &dev->filelist);
370 mutex_unlock(&dev->filelist_mutex);
371
372 #ifdef __alpha__
373 /*
374 * Default the hose
375 */
376 if (!dev->hose) {
377 struct pci_dev *pci_dev;
378
379 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
380 if (pci_dev) {
381 dev->hose = pci_dev->sysdata;
382 pci_dev_put(pci_dev);
383 }
384 if (!dev->hose) {
385 struct pci_bus *b = list_entry(pci_root_buses.next,
386 struct pci_bus, node);
387 if (b)
388 dev->hose = b->sysdata;
389 }
390 }
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 falure.
408 */
drm_open(struct inode * inode,struct file * filp)409 int 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(iminor(inode));
417 if (IS_ERR(minor))
418 return PTR_ERR(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(&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(&drm_global_mutex);
443
444 return 0;
445
446 err_undo:
447 atomic_dec(&dev->open_count);
448 if (drm_dev_needs_global_mutex(dev))
449 mutex_unlock(&drm_global_mutex);
450 drm_minor_release(minor);
451 return retcode;
452 }
453 EXPORT_SYMBOL(drm_open);
454
drm_lastclose(struct drm_device * dev)455 void drm_lastclose(struct drm_device * dev)
456 {
457 DRM_DEBUG("\n");
458
459 if (dev->driver->lastclose)
460 dev->driver->lastclose(dev);
461 DRM_DEBUG("driver lastclose completed\n");
462
463 if (drm_core_check_feature(dev, 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 */
drm_release(struct inode * inode,struct file * filp)483 int 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_DEBUG("open_count = %d\n", atomic_read(&dev->open_count));
493
494 drm_close_helper(filp);
495
496 if (atomic_dec_and_test(&dev->open_count))
497 drm_lastclose(dev);
498
499 if (drm_dev_needs_global_mutex(dev))
500 mutex_unlock(&drm_global_mutex);
501
502 drm_minor_release(minor);
503
504 return 0;
505 }
506 EXPORT_SYMBOL(drm_release);
507
508 /**
509 * drm_release_noglobal - release method for DRM file
510 * @inode: device inode
511 * @filp: file pointer.
512 *
513 * This function may be used by drivers as their &file_operations.release
514 * method. It frees any resources associated with the open file prior to taking
515 * the drm_global_mutex, which then calls the &drm_driver.postclose driver
516 * callback. If this is the last open file for the DRM device also proceeds to
517 * call the &drm_driver.lastclose driver callback.
518 *
519 * RETURNS:
520 *
521 * Always succeeds and returns 0.
522 */
drm_release_noglobal(struct inode * inode,struct file * filp)523 int drm_release_noglobal(struct inode *inode, struct file *filp)
524 {
525 struct drm_file *file_priv = filp->private_data;
526 struct drm_minor *minor = file_priv->minor;
527 struct drm_device *dev = minor->dev;
528
529 drm_close_helper(filp);
530
531 if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) {
532 drm_lastclose(dev);
533 mutex_unlock(&drm_global_mutex);
534 }
535
536 drm_minor_release(minor);
537
538 return 0;
539 }
540 EXPORT_SYMBOL(drm_release_noglobal);
541
542 /**
543 * drm_read - read method for DRM file
544 * @filp: file pointer
545 * @buffer: userspace destination pointer for the read
546 * @count: count in bytes to read
547 * @offset: offset to read
548 *
549 * This function must be used by drivers as their &file_operations.read
550 * method iff they use DRM events for asynchronous signalling to userspace.
551 * Since events are used by the KMS API for vblank and page flip completion this
552 * means all modern display drivers must use it.
553 *
554 * @offset is ignored, DRM events are read like a pipe. Therefore drivers also
555 * must set the &file_operation.llseek to no_llseek(). Polling support is
556 * provided by drm_poll().
557 *
558 * This function will only ever read a full event. Therefore userspace must
559 * supply a big enough buffer to fit any event to ensure forward progress. Since
560 * the maximum event space is currently 4K it's recommended to just use that for
561 * safety.
562 *
563 * RETURNS:
564 *
565 * Number of bytes read (always aligned to full events, and can be 0) or a
566 * negative error code on failure.
567 */
drm_read(struct file * filp,char __user * buffer,size_t count,loff_t * offset)568 ssize_t drm_read(struct file *filp, char __user *buffer,
569 size_t count, loff_t *offset)
570 {
571 struct drm_file *file_priv = filp->private_data;
572 struct drm_device *dev = file_priv->minor->dev;
573 ssize_t ret;
574
575 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
576 if (ret)
577 return ret;
578
579 for (;;) {
580 struct drm_pending_event *e = NULL;
581
582 spin_lock_irq(&dev->event_lock);
583 if (!list_empty(&file_priv->event_list)) {
584 e = list_first_entry(&file_priv->event_list,
585 struct drm_pending_event, link);
586 file_priv->event_space += e->event->length;
587 list_del(&e->link);
588 }
589 spin_unlock_irq(&dev->event_lock);
590
591 if (e == NULL) {
592 if (ret)
593 break;
594
595 if (filp->f_flags & O_NONBLOCK) {
596 ret = -EAGAIN;
597 break;
598 }
599
600 mutex_unlock(&file_priv->event_read_lock);
601 ret = wait_event_interruptible(file_priv->event_wait,
602 !list_empty(&file_priv->event_list));
603 if (ret >= 0)
604 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
605 if (ret)
606 return ret;
607 } else {
608 unsigned length = e->event->length;
609
610 if (length > count - ret) {
611 put_back_event:
612 spin_lock_irq(&dev->event_lock);
613 file_priv->event_space -= length;
614 list_add(&e->link, &file_priv->event_list);
615 spin_unlock_irq(&dev->event_lock);
616 wake_up_interruptible_poll(&file_priv->event_wait,
617 EPOLLIN | EPOLLRDNORM);
618 break;
619 }
620
621 if (copy_to_user(buffer + ret, e->event, length)) {
622 if (ret == 0)
623 ret = -EFAULT;
624 goto put_back_event;
625 }
626
627 ret += length;
628 kfree(e);
629 }
630 }
631 mutex_unlock(&file_priv->event_read_lock);
632
633 return ret;
634 }
635 EXPORT_SYMBOL(drm_read);
636
637 /**
638 * drm_poll - poll method for DRM file
639 * @filp: file pointer
640 * @wait: poll waiter table
641 *
642 * This function must be used by drivers as their &file_operations.read method
643 * iff they use DRM events for asynchronous signalling to userspace. Since
644 * events are used by the KMS API for vblank and page flip completion this means
645 * all modern display drivers must use it.
646 *
647 * See also drm_read().
648 *
649 * RETURNS:
650 *
651 * Mask of POLL flags indicating the current status of the file.
652 */
drm_poll(struct file * filp,struct poll_table_struct * wait)653 __poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
654 {
655 struct drm_file *file_priv = filp->private_data;
656 __poll_t mask = 0;
657
658 poll_wait(filp, &file_priv->event_wait, wait);
659
660 if (!list_empty(&file_priv->event_list))
661 mask |= EPOLLIN | EPOLLRDNORM;
662
663 return mask;
664 }
665 EXPORT_SYMBOL(drm_poll);
666
667 /**
668 * drm_event_reserve_init_locked - 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 * This is the locked version of drm_event_reserve_init() for callers which
685 * already hold &drm_device.event_lock.
686 *
687 * RETURNS:
688 *
689 * 0 on success or a negative error code on failure.
690 */
drm_event_reserve_init_locked(struct drm_device * dev,struct drm_file * file_priv,struct drm_pending_event * p,struct drm_event * e)691 int drm_event_reserve_init_locked(struct drm_device *dev,
692 struct drm_file *file_priv,
693 struct drm_pending_event *p,
694 struct drm_event *e)
695 {
696 if (file_priv->event_space < e->length)
697 return -ENOMEM;
698
699 file_priv->event_space -= e->length;
700
701 p->event = e;
702 list_add(&p->pending_link, &file_priv->pending_event_list);
703 p->file_priv = file_priv;
704
705 return 0;
706 }
707 EXPORT_SYMBOL(drm_event_reserve_init_locked);
708
709 /**
710 * drm_event_reserve_init - init a DRM event and reserve space for it
711 * @dev: DRM device
712 * @file_priv: DRM file private data
713 * @p: tracking structure for the pending event
714 * @e: actual event data to deliver to userspace
715 *
716 * This function prepares the passed in event for eventual delivery. If the event
717 * doesn't get delivered (because the IOCTL fails later on, before queuing up
718 * anything) then the even must be cancelled and freed using
719 * drm_event_cancel_free(). Successfully initialized events should be sent out
720 * using drm_send_event() or drm_send_event_locked() to signal completion of the
721 * asynchronous event to userspace.
722 *
723 * If callers embedded @p into a larger structure it must be allocated with
724 * kmalloc and @p must be the first member element.
725 *
726 * Callers which already hold &drm_device.event_lock should use
727 * drm_event_reserve_init_locked() instead.
728 *
729 * RETURNS:
730 *
731 * 0 on success or a negative error code on failure.
732 */
drm_event_reserve_init(struct drm_device * dev,struct drm_file * file_priv,struct drm_pending_event * p,struct drm_event * e)733 int drm_event_reserve_init(struct drm_device *dev,
734 struct drm_file *file_priv,
735 struct drm_pending_event *p,
736 struct drm_event *e)
737 {
738 unsigned long flags;
739 int ret;
740
741 spin_lock_irqsave(&dev->event_lock, flags);
742 ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
743 spin_unlock_irqrestore(&dev->event_lock, flags);
744
745 return ret;
746 }
747 EXPORT_SYMBOL(drm_event_reserve_init);
748
749 /**
750 * drm_event_cancel_free - free a DRM event and release its space
751 * @dev: DRM device
752 * @p: tracking structure for the pending event
753 *
754 * This function frees the event @p initialized with drm_event_reserve_init()
755 * and releases any allocated space. It is used to cancel an event when the
756 * nonblocking operation could not be submitted and needed to be aborted.
757 */
drm_event_cancel_free(struct drm_device * dev,struct drm_pending_event * p)758 void drm_event_cancel_free(struct drm_device *dev,
759 struct drm_pending_event *p)
760 {
761 unsigned long flags;
762
763 spin_lock_irqsave(&dev->event_lock, flags);
764 if (p->file_priv) {
765 p->file_priv->event_space += p->event->length;
766 list_del(&p->pending_link);
767 }
768 spin_unlock_irqrestore(&dev->event_lock, flags);
769
770 if (p->fence)
771 dma_fence_put(p->fence);
772
773 kfree(p);
774 }
775 EXPORT_SYMBOL(drm_event_cancel_free);
776
777 /**
778 * drm_send_event_locked - send DRM event to file descriptor
779 * @dev: DRM device
780 * @e: DRM event to deliver
781 *
782 * This function sends the event @e, initialized with drm_event_reserve_init(),
783 * to its associated userspace DRM file. Callers must already hold
784 * &drm_device.event_lock, see drm_send_event() for the unlocked version.
785 *
786 * Note that the core will take care of unlinking and disarming events when the
787 * corresponding DRM file is closed. Drivers need not worry about whether the
788 * DRM file for this event still exists and can call this function upon
789 * completion of the asynchronous work unconditionally.
790 */
drm_send_event_locked(struct drm_device * dev,struct drm_pending_event * e)791 void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
792 {
793 assert_spin_locked(&dev->event_lock);
794
795 if (e->completion) {
796 complete_all(e->completion);
797 e->completion_release(e->completion);
798 e->completion = NULL;
799 }
800
801 if (e->fence) {
802 dma_fence_signal(e->fence);
803 dma_fence_put(e->fence);
804 }
805
806 if (!e->file_priv) {
807 kfree(e);
808 return;
809 }
810
811 list_del(&e->pending_link);
812 list_add_tail(&e->link,
813 &e->file_priv->event_list);
814 wake_up_interruptible_poll(&e->file_priv->event_wait,
815 EPOLLIN | EPOLLRDNORM);
816 }
817 EXPORT_SYMBOL(drm_send_event_locked);
818
819 /**
820 * drm_send_event - send DRM event to file descriptor
821 * @dev: DRM device
822 * @e: DRM event to deliver
823 *
824 * This function sends the event @e, initialized with drm_event_reserve_init(),
825 * to its associated userspace DRM file. This function acquires
826 * &drm_device.event_lock, see drm_send_event_locked() for callers which already
827 * hold this lock.
828 *
829 * Note that the core will take care of unlinking and disarming events when the
830 * corresponding DRM file is closed. Drivers need not worry about whether the
831 * DRM file for this event still exists and can call this function upon
832 * completion of the asynchronous work unconditionally.
833 */
drm_send_event(struct drm_device * dev,struct drm_pending_event * e)834 void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
835 {
836 unsigned long irqflags;
837
838 spin_lock_irqsave(&dev->event_lock, irqflags);
839 drm_send_event_locked(dev, e);
840 spin_unlock_irqrestore(&dev->event_lock, irqflags);
841 }
842 EXPORT_SYMBOL(drm_send_event);
843
844 /**
845 * mock_drm_getfile - Create a new struct file for the drm device
846 * @minor: drm minor to wrap (e.g. #drm_device.primary)
847 * @flags: file creation mode (O_RDWR etc)
848 *
849 * This create a new struct file that wraps a DRM file context around a
850 * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without
851 * invoking userspace. The struct file may be operated on using its f_op
852 * (the drm_device.driver.fops) to mimick userspace operations, or be supplied
853 * to userspace facing functions as an internal/anonymous client.
854 *
855 * RETURNS:
856 * Pointer to newly created struct file, ERR_PTR on failure.
857 */
mock_drm_getfile(struct drm_minor * minor,unsigned int flags)858 struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
859 {
860 struct drm_device *dev = minor->dev;
861 struct drm_file *priv;
862 struct file *file;
863
864 priv = drm_file_alloc(minor);
865 if (IS_ERR(priv))
866 return ERR_CAST(priv);
867
868 file = anon_inode_getfile("drm", dev->driver->fops, priv, flags);
869 if (IS_ERR(file)) {
870 drm_file_free(priv);
871 return file;
872 }
873
874 /* Everyone shares a single global address space */
875 file->f_mapping = dev->anon_inode->i_mapping;
876
877 drm_dev_get(dev);
878 priv->filp = file;
879
880 return file;
881 }
882 EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
883
884 #ifdef CONFIG_MMU
885 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
886 /*
887 * drm_addr_inflate() attempts to construct an aligned area by inflating
888 * the area size and skipping the unaligned start of the area.
889 * adapted from shmem_get_unmapped_area()
890 */
drm_addr_inflate(unsigned long addr,unsigned long len,unsigned long pgoff,unsigned long flags,unsigned long huge_size)891 static unsigned long drm_addr_inflate(unsigned long addr,
892 unsigned long len,
893 unsigned long pgoff,
894 unsigned long flags,
895 unsigned long huge_size)
896 {
897 unsigned long offset, inflated_len;
898 unsigned long inflated_addr;
899 unsigned long inflated_offset;
900
901 offset = (pgoff << PAGE_SHIFT) & (huge_size - 1);
902 if (offset && offset + len < 2 * huge_size)
903 return addr;
904 if ((addr & (huge_size - 1)) == offset)
905 return addr;
906
907 inflated_len = len + huge_size - PAGE_SIZE;
908 if (inflated_len > TASK_SIZE)
909 return addr;
910 if (inflated_len < len)
911 return addr;
912
913 inflated_addr = current->mm->get_unmapped_area(NULL, 0, inflated_len,
914 0, flags);
915 if (IS_ERR_VALUE(inflated_addr))
916 return addr;
917 if (inflated_addr & ~PAGE_MASK)
918 return addr;
919
920 inflated_offset = inflated_addr & (huge_size - 1);
921 inflated_addr += offset - inflated_offset;
922 if (inflated_offset > offset)
923 inflated_addr += huge_size;
924
925 if (inflated_addr > TASK_SIZE - len)
926 return addr;
927
928 return inflated_addr;
929 }
930
931 /**
932 * drm_get_unmapped_area() - Get an unused user-space virtual memory area
933 * suitable for huge page table entries.
934 * @file: The struct file representing the address space being mmap()'d.
935 * @uaddr: Start address suggested by user-space.
936 * @len: Length of the area.
937 * @pgoff: The page offset into the address space.
938 * @flags: mmap flags
939 * @mgr: The address space manager used by the drm driver. This argument can
940 * probably be removed at some point when all drivers use the same
941 * address space manager.
942 *
943 * This function attempts to find an unused user-space virtual memory area
944 * that can accommodate the size we want to map, and that is properly
945 * aligned to facilitate huge page table entries matching actual
946 * huge pages or huge page aligned memory in buffer objects. Buffer objects
947 * are assumed to start at huge page boundary pfns (io memory) or be
948 * populated by huge pages aligned to the start of the buffer object
949 * (system- or coherent memory). Adapted from shmem_get_unmapped_area.
950 *
951 * Return: aligned user-space address.
952 */
drm_get_unmapped_area(struct file * file,unsigned long uaddr,unsigned long len,unsigned long pgoff,unsigned long flags,struct drm_vma_offset_manager * mgr)953 unsigned long drm_get_unmapped_area(struct file *file,
954 unsigned long uaddr, unsigned long len,
955 unsigned long pgoff, unsigned long flags,
956 struct drm_vma_offset_manager *mgr)
957 {
958 unsigned long addr;
959 unsigned long inflated_addr;
960 struct drm_vma_offset_node *node;
961
962 if (len > TASK_SIZE)
963 return -ENOMEM;
964
965 /*
966 * @pgoff is the file page-offset the huge page boundaries of
967 * which typically aligns to physical address huge page boundaries.
968 * That's not true for DRM, however, where physical address huge
969 * page boundaries instead are aligned with the offset from
970 * buffer object start. So adjust @pgoff to be the offset from
971 * buffer object start.
972 */
973 drm_vma_offset_lock_lookup(mgr);
974 node = drm_vma_offset_lookup_locked(mgr, pgoff, 1);
975 if (node)
976 pgoff -= node->vm_node.start;
977 drm_vma_offset_unlock_lookup(mgr);
978
979 addr = current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
980 if (IS_ERR_VALUE(addr))
981 return addr;
982 if (addr & ~PAGE_MASK)
983 return addr;
984 if (addr > TASK_SIZE - len)
985 return addr;
986
987 if (len < HPAGE_PMD_SIZE)
988 return addr;
989 if (flags & MAP_FIXED)
990 return addr;
991 /*
992 * Our priority is to support MAP_SHARED mapped hugely;
993 * and support MAP_PRIVATE mapped hugely too, until it is COWed.
994 * But if caller specified an address hint, respect that as before.
995 */
996 if (uaddr)
997 return addr;
998
999 inflated_addr = drm_addr_inflate(addr, len, pgoff, flags,
1000 HPAGE_PMD_SIZE);
1001
1002 if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) &&
1003 len >= HPAGE_PUD_SIZE)
1004 inflated_addr = drm_addr_inflate(inflated_addr, len, pgoff,
1005 flags, HPAGE_PUD_SIZE);
1006 return inflated_addr;
1007 }
1008 #else /* CONFIG_TRANSPARENT_HUGEPAGE */
drm_get_unmapped_area(struct file * file,unsigned long uaddr,unsigned long len,unsigned long pgoff,unsigned long flags,struct drm_vma_offset_manager * mgr)1009 unsigned long drm_get_unmapped_area(struct file *file,
1010 unsigned long uaddr, unsigned long len,
1011 unsigned long pgoff, unsigned long flags,
1012 struct drm_vma_offset_manager *mgr)
1013 {
1014 return current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
1015 }
1016 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1017 EXPORT_SYMBOL_GPL(drm_get_unmapped_area);
1018 #endif /* CONFIG_MMU */
1019