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 spin_lock_init(&file->master_lookup_lock);
181 mutex_init(&file->event_read_lock);
182
183 if (drm_core_check_feature(dev, DRIVER_GEM))
184 drm_gem_open(dev, file);
185
186 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
187 drm_syncobj_open(file);
188
189 drm_prime_init_file_private(&file->prime);
190
191 if (dev->driver->open) {
192 ret = dev->driver->open(dev, file);
193 if (ret < 0)
194 goto out_prime_destroy;
195 }
196
197 return file;
198
199 out_prime_destroy:
200 drm_prime_destroy_file_private(&file->prime);
201 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
202 drm_syncobj_release(file);
203 if (drm_core_check_feature(dev, DRIVER_GEM))
204 drm_gem_release(dev, file);
205 put_pid(file->pid);
206 kfree(file);
207
208 return ERR_PTR(ret);
209 }
210
drm_events_release(struct drm_file * file_priv)211 static void drm_events_release(struct drm_file *file_priv)
212 {
213 struct drm_device *dev = file_priv->minor->dev;
214 struct drm_pending_event *e, *et;
215 unsigned long flags;
216
217 spin_lock_irqsave(&dev->event_lock, flags);
218
219 /* Unlink pending events */
220 list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
221 pending_link) {
222 list_del(&e->pending_link);
223 e->file_priv = NULL;
224 }
225
226 /* Remove unconsumed events */
227 list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
228 list_del(&e->link);
229 kfree(e);
230 }
231
232 spin_unlock_irqrestore(&dev->event_lock, flags);
233 }
234
235 /**
236 * drm_file_free - free file context
237 * @file: context to free, or NULL
238 *
239 * This destroys and deallocates a DRM file context previously allocated via
240 * drm_file_alloc(). The caller must make sure to unlink it from any contexts
241 * before calling this.
242 *
243 * If NULL is passed, this is a no-op.
244 *
245 * RETURNS:
246 * 0 on success, or error code on failure.
247 */
drm_file_free(struct drm_file * file)248 void drm_file_free(struct drm_file *file)
249 {
250 struct drm_device *dev;
251
252 if (!file)
253 return;
254
255 dev = file->minor->dev;
256
257 DRM_DEBUG("comm=\"%s\", pid=%d, dev=0x%lx, open_count=%d\n",
258 current->comm, task_pid_nr(current),
259 (long)old_encode_dev(file->minor->kdev->devt),
260 atomic_read(&dev->open_count));
261
262 if (drm_core_check_feature(dev, DRIVER_LEGACY) &&
263 dev->driver->preclose)
264 dev->driver->preclose(dev, file);
265
266 if (drm_core_check_feature(dev, DRIVER_LEGACY))
267 drm_legacy_lock_release(dev, file->filp);
268
269 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
270 drm_legacy_reclaim_buffers(dev, file);
271
272 drm_events_release(file);
273
274 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
275 drm_fb_release(file);
276 drm_property_destroy_user_blobs(dev, file);
277 }
278
279 if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
280 drm_syncobj_release(file);
281
282 if (drm_core_check_feature(dev, DRIVER_GEM))
283 drm_gem_release(dev, file);
284
285 drm_legacy_ctxbitmap_flush(dev, file);
286
287 if (drm_is_primary_client(file))
288 drm_master_release(file);
289
290 if (dev->driver->postclose)
291 dev->driver->postclose(dev, file);
292
293 drm_prime_destroy_file_private(&file->prime);
294
295 WARN_ON(!list_empty(&file->event_list));
296
297 put_pid(file->pid);
298 kfree(file);
299 }
300
drm_close_helper(struct file * filp)301 static void drm_close_helper(struct file *filp)
302 {
303 struct drm_file *file_priv = filp->private_data;
304 struct drm_device *dev = file_priv->minor->dev;
305
306 mutex_lock(&dev->filelist_mutex);
307 list_del(&file_priv->lhead);
308 mutex_unlock(&dev->filelist_mutex);
309
310 drm_file_free(file_priv);
311 }
312
313 /*
314 * Check whether DRI will run on this CPU.
315 *
316 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
317 */
drm_cpu_valid(void)318 static int drm_cpu_valid(void)
319 {
320 #if defined(__sparc__) && !defined(__sparc_v9__)
321 return 0; /* No cmpxchg before v9 sparc. */
322 #endif
323 return 1;
324 }
325
326 /*
327 * Called whenever a process opens a drm node
328 *
329 * \param filp file pointer.
330 * \param minor acquired minor-object.
331 * \return zero on success or a negative number on failure.
332 *
333 * Creates and initializes a drm_file structure for the file private data in \p
334 * filp and add it into the double linked list in \p dev.
335 */
drm_open_helper(struct file * filp,struct drm_minor * minor)336 static int drm_open_helper(struct file *filp, struct drm_minor *minor)
337 {
338 struct drm_device *dev = minor->dev;
339 struct drm_file *priv;
340 int ret;
341
342 if (filp->f_flags & O_EXCL)
343 return -EBUSY; /* No exclusive opens */
344 if (!drm_cpu_valid())
345 return -EINVAL;
346 if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
347 dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
348 return -EINVAL;
349
350 DRM_DEBUG("comm=\"%s\", pid=%d, minor=%d\n", current->comm,
351 task_pid_nr(current), minor->index);
352
353 priv = drm_file_alloc(minor);
354 if (IS_ERR(priv))
355 return PTR_ERR(priv);
356
357 if (drm_is_primary_client(priv)) {
358 ret = drm_master_open(priv);
359 if (ret) {
360 drm_file_free(priv);
361 return ret;
362 }
363 }
364
365 filp->private_data = priv;
366 filp->f_mode |= FMODE_UNSIGNED_OFFSET;
367 priv->filp = filp;
368
369 mutex_lock(&dev->filelist_mutex);
370 list_add(&priv->lhead, &dev->filelist);
371 mutex_unlock(&dev->filelist_mutex);
372
373 #ifdef __alpha__
374 /*
375 * Default the hose
376 */
377 if (!dev->hose) {
378 struct pci_dev *pci_dev;
379
380 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
381 if (pci_dev) {
382 dev->hose = pci_dev->sysdata;
383 pci_dev_put(pci_dev);
384 }
385 if (!dev->hose) {
386 struct pci_bus *b = list_entry(pci_root_buses.next,
387 struct pci_bus, node);
388 if (b)
389 dev->hose = b->sysdata;
390 }
391 }
392 #endif
393
394 return 0;
395 }
396
397 /**
398 * drm_open - open method for DRM file
399 * @inode: device inode
400 * @filp: file pointer.
401 *
402 * This function must be used by drivers as their &file_operations.open method.
403 * It looks up the correct DRM device and instantiates all the per-file
404 * resources for it. It also calls the &drm_driver.open driver callback.
405 *
406 * RETURNS:
407 *
408 * 0 on success or negative errno value on falure.
409 */
drm_open(struct inode * inode,struct file * filp)410 int drm_open(struct inode *inode, struct file *filp)
411 {
412 struct drm_device *dev;
413 struct drm_minor *minor;
414 int retcode;
415 int need_setup = 0;
416
417 minor = drm_minor_acquire(iminor(inode));
418 if (IS_ERR(minor))
419 return PTR_ERR(minor);
420
421 dev = minor->dev;
422 if (drm_dev_needs_global_mutex(dev))
423 mutex_lock(&drm_global_mutex);
424
425 if (!atomic_fetch_inc(&dev->open_count))
426 need_setup = 1;
427
428 /* share address_space across all char-devs of a single device */
429 filp->f_mapping = dev->anon_inode->i_mapping;
430
431 retcode = drm_open_helper(filp, minor);
432 if (retcode)
433 goto err_undo;
434 if (need_setup) {
435 retcode = drm_legacy_setup(dev);
436 if (retcode) {
437 drm_close_helper(filp);
438 goto err_undo;
439 }
440 }
441
442 if (drm_dev_needs_global_mutex(dev))
443 mutex_unlock(&drm_global_mutex);
444
445 return 0;
446
447 err_undo:
448 atomic_dec(&dev->open_count);
449 if (drm_dev_needs_global_mutex(dev))
450 mutex_unlock(&drm_global_mutex);
451 drm_minor_release(minor);
452 return retcode;
453 }
454 EXPORT_SYMBOL(drm_open);
455
drm_lastclose(struct drm_device * dev)456 void drm_lastclose(struct drm_device * dev)
457 {
458 DRM_DEBUG("\n");
459
460 if (dev->driver->lastclose)
461 dev->driver->lastclose(dev);
462 DRM_DEBUG("driver lastclose completed\n");
463
464 if (drm_core_check_feature(dev, DRIVER_LEGACY))
465 drm_legacy_dev_reinit(dev);
466
467 drm_client_dev_restore(dev);
468 }
469
470 /**
471 * drm_release - release method for DRM file
472 * @inode: device inode
473 * @filp: file pointer.
474 *
475 * This function must be used by drivers as their &file_operations.release
476 * method. It frees any resources associated with the open file, and calls the
477 * &drm_driver.postclose driver callback. If this is the last open file for the
478 * DRM device also proceeds to call the &drm_driver.lastclose driver callback.
479 *
480 * RETURNS:
481 *
482 * Always succeeds and returns 0.
483 */
drm_release(struct inode * inode,struct file * filp)484 int drm_release(struct inode *inode, struct file *filp)
485 {
486 struct drm_file *file_priv = filp->private_data;
487 struct drm_minor *minor = file_priv->minor;
488 struct drm_device *dev = minor->dev;
489
490 if (drm_dev_needs_global_mutex(dev))
491 mutex_lock(&drm_global_mutex);
492
493 DRM_DEBUG("open_count = %d\n", atomic_read(&dev->open_count));
494
495 drm_close_helper(filp);
496
497 if (atomic_dec_and_test(&dev->open_count))
498 drm_lastclose(dev);
499
500 if (drm_dev_needs_global_mutex(dev))
501 mutex_unlock(&drm_global_mutex);
502
503 drm_minor_release(minor);
504
505 return 0;
506 }
507 EXPORT_SYMBOL(drm_release);
508
509 /**
510 * drm_release_noglobal - release method for DRM file
511 * @inode: device inode
512 * @filp: file pointer.
513 *
514 * This function may be used by drivers as their &file_operations.release
515 * method. It frees any resources associated with the open file prior to taking
516 * the drm_global_mutex, which then calls the &drm_driver.postclose driver
517 * callback. If this is the last open file for the DRM device also proceeds to
518 * call the &drm_driver.lastclose driver callback.
519 *
520 * RETURNS:
521 *
522 * Always succeeds and returns 0.
523 */
drm_release_noglobal(struct inode * inode,struct file * filp)524 int drm_release_noglobal(struct inode *inode, struct file *filp)
525 {
526 struct drm_file *file_priv = filp->private_data;
527 struct drm_minor *minor = file_priv->minor;
528 struct drm_device *dev = minor->dev;
529
530 drm_close_helper(filp);
531
532 if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) {
533 drm_lastclose(dev);
534 mutex_unlock(&drm_global_mutex);
535 }
536
537 drm_minor_release(minor);
538
539 return 0;
540 }
541 EXPORT_SYMBOL(drm_release_noglobal);
542
543 /**
544 * drm_read - read method for DRM file
545 * @filp: file pointer
546 * @buffer: userspace destination pointer for the read
547 * @count: count in bytes to read
548 * @offset: offset to read
549 *
550 * This function must be used by drivers as their &file_operations.read
551 * method iff they use DRM events for asynchronous signalling to userspace.
552 * Since events are used by the KMS API for vblank and page flip completion this
553 * means all modern display drivers must use it.
554 *
555 * @offset is ignored, DRM events are read like a pipe. Therefore drivers also
556 * must set the &file_operation.llseek to no_llseek(). Polling support is
557 * provided by drm_poll().
558 *
559 * This function will only ever read a full event. Therefore userspace must
560 * supply a big enough buffer to fit any event to ensure forward progress. Since
561 * the maximum event space is currently 4K it's recommended to just use that for
562 * safety.
563 *
564 * RETURNS:
565 *
566 * Number of bytes read (always aligned to full events, and can be 0) or a
567 * negative error code on failure.
568 */
drm_read(struct file * filp,char __user * buffer,size_t count,loff_t * offset)569 ssize_t drm_read(struct file *filp, char __user *buffer,
570 size_t count, loff_t *offset)
571 {
572 struct drm_file *file_priv = filp->private_data;
573 struct drm_device *dev = file_priv->minor->dev;
574 ssize_t ret;
575
576 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
577 if (ret)
578 return ret;
579
580 for (;;) {
581 struct drm_pending_event *e = NULL;
582
583 spin_lock_irq(&dev->event_lock);
584 if (!list_empty(&file_priv->event_list)) {
585 e = list_first_entry(&file_priv->event_list,
586 struct drm_pending_event, link);
587 file_priv->event_space += e->event->length;
588 list_del(&e->link);
589 }
590 spin_unlock_irq(&dev->event_lock);
591
592 if (e == NULL) {
593 if (ret)
594 break;
595
596 if (filp->f_flags & O_NONBLOCK) {
597 ret = -EAGAIN;
598 break;
599 }
600
601 mutex_unlock(&file_priv->event_read_lock);
602 ret = wait_event_interruptible(file_priv->event_wait,
603 !list_empty(&file_priv->event_list));
604 if (ret >= 0)
605 ret = mutex_lock_interruptible(&file_priv->event_read_lock);
606 if (ret)
607 return ret;
608 } else {
609 unsigned length = e->event->length;
610
611 if (length > count - ret) {
612 put_back_event:
613 spin_lock_irq(&dev->event_lock);
614 file_priv->event_space -= length;
615 list_add(&e->link, &file_priv->event_list);
616 spin_unlock_irq(&dev->event_lock);
617 wake_up_interruptible_poll(&file_priv->event_wait,
618 EPOLLIN | EPOLLRDNORM);
619 break;
620 }
621
622 if (copy_to_user(buffer + ret, e->event, length)) {
623 if (ret == 0)
624 ret = -EFAULT;
625 goto put_back_event;
626 }
627
628 ret += length;
629 kfree(e);
630 }
631 }
632 mutex_unlock(&file_priv->event_read_lock);
633
634 return ret;
635 }
636 EXPORT_SYMBOL(drm_read);
637
638 /**
639 * drm_poll - poll method for DRM file
640 * @filp: file pointer
641 * @wait: poll waiter table
642 *
643 * This function must be used by drivers as their &file_operations.read method
644 * iff they use DRM events for asynchronous signalling to userspace. Since
645 * events are used by the KMS API for vblank and page flip completion this means
646 * all modern display drivers must use it.
647 *
648 * See also drm_read().
649 *
650 * RETURNS:
651 *
652 * Mask of POLL flags indicating the current status of the file.
653 */
drm_poll(struct file * filp,struct poll_table_struct * wait)654 __poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
655 {
656 struct drm_file *file_priv = filp->private_data;
657 __poll_t mask = 0;
658
659 poll_wait(filp, &file_priv->event_wait, wait);
660
661 if (!list_empty(&file_priv->event_list))
662 mask |= EPOLLIN | EPOLLRDNORM;
663
664 return mask;
665 }
666 EXPORT_SYMBOL(drm_poll);
667
668 /**
669 * drm_event_reserve_init_locked - init a DRM event and reserve space for it
670 * @dev: DRM device
671 * @file_priv: DRM file private data
672 * @p: tracking structure for the pending event
673 * @e: actual event data to deliver to userspace
674 *
675 * This function prepares the passed in event for eventual delivery. If the event
676 * doesn't get delivered (because the IOCTL fails later on, before queuing up
677 * anything) then the even must be cancelled and freed using
678 * drm_event_cancel_free(). Successfully initialized events should be sent out
679 * using drm_send_event() or drm_send_event_locked() to signal completion of the
680 * asynchronous event to userspace.
681 *
682 * If callers embedded @p into a larger structure it must be allocated with
683 * kmalloc and @p must be the first member element.
684 *
685 * This is the locked version of drm_event_reserve_init() for callers which
686 * already hold &drm_device.event_lock.
687 *
688 * RETURNS:
689 *
690 * 0 on success or a negative error code on failure.
691 */
drm_event_reserve_init_locked(struct drm_device * dev,struct drm_file * file_priv,struct drm_pending_event * p,struct drm_event * e)692 int drm_event_reserve_init_locked(struct drm_device *dev,
693 struct drm_file *file_priv,
694 struct drm_pending_event *p,
695 struct drm_event *e)
696 {
697 if (file_priv->event_space < e->length)
698 return -ENOMEM;
699
700 file_priv->event_space -= e->length;
701
702 p->event = e;
703 list_add(&p->pending_link, &file_priv->pending_event_list);
704 p->file_priv = file_priv;
705
706 return 0;
707 }
708 EXPORT_SYMBOL(drm_event_reserve_init_locked);
709
710 /**
711 * drm_event_reserve_init - init a DRM event and reserve space for it
712 * @dev: DRM device
713 * @file_priv: DRM file private data
714 * @p: tracking structure for the pending event
715 * @e: actual event data to deliver to userspace
716 *
717 * This function prepares the passed in event for eventual delivery. If the event
718 * doesn't get delivered (because the IOCTL fails later on, before queuing up
719 * anything) then the even must be cancelled and freed using
720 * drm_event_cancel_free(). Successfully initialized events should be sent out
721 * using drm_send_event() or drm_send_event_locked() to signal completion of the
722 * asynchronous event to userspace.
723 *
724 * If callers embedded @p into a larger structure it must be allocated with
725 * kmalloc and @p must be the first member element.
726 *
727 * Callers which already hold &drm_device.event_lock should use
728 * drm_event_reserve_init_locked() instead.
729 *
730 * RETURNS:
731 *
732 * 0 on success or a negative error code on failure.
733 */
drm_event_reserve_init(struct drm_device * dev,struct drm_file * file_priv,struct drm_pending_event * p,struct drm_event * e)734 int drm_event_reserve_init(struct drm_device *dev,
735 struct drm_file *file_priv,
736 struct drm_pending_event *p,
737 struct drm_event *e)
738 {
739 unsigned long flags;
740 int ret;
741
742 spin_lock_irqsave(&dev->event_lock, flags);
743 ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
744 spin_unlock_irqrestore(&dev->event_lock, flags);
745
746 return ret;
747 }
748 EXPORT_SYMBOL(drm_event_reserve_init);
749
750 /**
751 * drm_event_cancel_free - free a DRM event and release its space
752 * @dev: DRM device
753 * @p: tracking structure for the pending event
754 *
755 * This function frees the event @p initialized with drm_event_reserve_init()
756 * and releases any allocated space. It is used to cancel an event when the
757 * nonblocking operation could not be submitted and needed to be aborted.
758 */
drm_event_cancel_free(struct drm_device * dev,struct drm_pending_event * p)759 void drm_event_cancel_free(struct drm_device *dev,
760 struct drm_pending_event *p)
761 {
762 unsigned long flags;
763
764 spin_lock_irqsave(&dev->event_lock, flags);
765 if (p->file_priv) {
766 p->file_priv->event_space += p->event->length;
767 list_del(&p->pending_link);
768 }
769 spin_unlock_irqrestore(&dev->event_lock, flags);
770
771 if (p->fence)
772 dma_fence_put(p->fence);
773
774 kfree(p);
775 }
776 EXPORT_SYMBOL(drm_event_cancel_free);
777
778 /**
779 * drm_send_event_locked - send DRM event to file descriptor
780 * @dev: DRM device
781 * @e: DRM event to deliver
782 *
783 * This function sends the event @e, initialized with drm_event_reserve_init(),
784 * to its associated userspace DRM file. Callers must already hold
785 * &drm_device.event_lock, see drm_send_event() for the unlocked version.
786 *
787 * Note that the core will take care of unlinking and disarming events when the
788 * corresponding DRM file is closed. Drivers need not worry about whether the
789 * DRM file for this event still exists and can call this function upon
790 * completion of the asynchronous work unconditionally.
791 */
drm_send_event_locked(struct drm_device * dev,struct drm_pending_event * e)792 void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
793 {
794 assert_spin_locked(&dev->event_lock);
795
796 if (e->completion) {
797 complete_all(e->completion);
798 e->completion_release(e->completion);
799 e->completion = NULL;
800 }
801
802 if (e->fence) {
803 dma_fence_signal(e->fence);
804 dma_fence_put(e->fence);
805 }
806
807 if (!e->file_priv) {
808 kfree(e);
809 return;
810 }
811
812 list_del(&e->pending_link);
813 list_add_tail(&e->link,
814 &e->file_priv->event_list);
815 wake_up_interruptible_poll(&e->file_priv->event_wait,
816 EPOLLIN | EPOLLRDNORM);
817 }
818 EXPORT_SYMBOL(drm_send_event_locked);
819
820 /**
821 * drm_send_event - send DRM event to file descriptor
822 * @dev: DRM device
823 * @e: DRM event to deliver
824 *
825 * This function sends the event @e, initialized with drm_event_reserve_init(),
826 * to its associated userspace DRM file. This function acquires
827 * &drm_device.event_lock, see drm_send_event_locked() for callers which already
828 * hold this lock.
829 *
830 * Note that the core will take care of unlinking and disarming events when the
831 * corresponding DRM file is closed. Drivers need not worry about whether the
832 * DRM file for this event still exists and can call this function upon
833 * completion of the asynchronous work unconditionally.
834 */
drm_send_event(struct drm_device * dev,struct drm_pending_event * e)835 void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
836 {
837 unsigned long irqflags;
838
839 spin_lock_irqsave(&dev->event_lock, irqflags);
840 drm_send_event_locked(dev, e);
841 spin_unlock_irqrestore(&dev->event_lock, irqflags);
842 }
843 EXPORT_SYMBOL(drm_send_event);
844
845 /**
846 * mock_drm_getfile - Create a new struct file for the drm device
847 * @minor: drm minor to wrap (e.g. #drm_device.primary)
848 * @flags: file creation mode (O_RDWR etc)
849 *
850 * This create a new struct file that wraps a DRM file context around a
851 * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without
852 * invoking userspace. The struct file may be operated on using its f_op
853 * (the drm_device.driver.fops) to mimick userspace operations, or be supplied
854 * to userspace facing functions as an internal/anonymous client.
855 *
856 * RETURNS:
857 * Pointer to newly created struct file, ERR_PTR on failure.
858 */
mock_drm_getfile(struct drm_minor * minor,unsigned int flags)859 struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
860 {
861 struct drm_device *dev = minor->dev;
862 struct drm_file *priv;
863 struct file *file;
864
865 priv = drm_file_alloc(minor);
866 if (IS_ERR(priv))
867 return ERR_CAST(priv);
868
869 file = anon_inode_getfile("drm", dev->driver->fops, priv, flags);
870 if (IS_ERR(file)) {
871 drm_file_free(priv);
872 return file;
873 }
874
875 /* Everyone shares a single global address space */
876 file->f_mapping = dev->anon_inode->i_mapping;
877
878 drm_dev_get(dev);
879 priv->filp = file;
880
881 return file;
882 }
883 EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
884
885 #ifdef CONFIG_MMU
886 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
887 /*
888 * drm_addr_inflate() attempts to construct an aligned area by inflating
889 * the area size and skipping the unaligned start of the area.
890 * adapted from shmem_get_unmapped_area()
891 */
drm_addr_inflate(unsigned long addr,unsigned long len,unsigned long pgoff,unsigned long flags,unsigned long huge_size)892 static unsigned long drm_addr_inflate(unsigned long addr,
893 unsigned long len,
894 unsigned long pgoff,
895 unsigned long flags,
896 unsigned long huge_size)
897 {
898 unsigned long offset, inflated_len;
899 unsigned long inflated_addr;
900 unsigned long inflated_offset;
901
902 offset = (pgoff << PAGE_SHIFT) & (huge_size - 1);
903 if (offset && offset + len < 2 * huge_size)
904 return addr;
905 if ((addr & (huge_size - 1)) == offset)
906 return addr;
907
908 inflated_len = len + huge_size - PAGE_SIZE;
909 if (inflated_len > TASK_SIZE)
910 return addr;
911 if (inflated_len < len)
912 return addr;
913
914 inflated_addr = current->mm->get_unmapped_area(NULL, 0, inflated_len,
915 0, flags);
916 if (IS_ERR_VALUE(inflated_addr))
917 return addr;
918 if (inflated_addr & ~PAGE_MASK)
919 return addr;
920
921 inflated_offset = inflated_addr & (huge_size - 1);
922 inflated_addr += offset - inflated_offset;
923 if (inflated_offset > offset)
924 inflated_addr += huge_size;
925
926 if (inflated_addr > TASK_SIZE - len)
927 return addr;
928
929 return inflated_addr;
930 }
931
932 /**
933 * drm_get_unmapped_area() - Get an unused user-space virtual memory area
934 * suitable for huge page table entries.
935 * @file: The struct file representing the address space being mmap()'d.
936 * @uaddr: Start address suggested by user-space.
937 * @len: Length of the area.
938 * @pgoff: The page offset into the address space.
939 * @flags: mmap flags
940 * @mgr: The address space manager used by the drm driver. This argument can
941 * probably be removed at some point when all drivers use the same
942 * address space manager.
943 *
944 * This function attempts to find an unused user-space virtual memory area
945 * that can accommodate the size we want to map, and that is properly
946 * aligned to facilitate huge page table entries matching actual
947 * huge pages or huge page aligned memory in buffer objects. Buffer objects
948 * are assumed to start at huge page boundary pfns (io memory) or be
949 * populated by huge pages aligned to the start of the buffer object
950 * (system- or coherent memory). Adapted from shmem_get_unmapped_area.
951 *
952 * Return: aligned user-space address.
953 */
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)954 unsigned long drm_get_unmapped_area(struct file *file,
955 unsigned long uaddr, unsigned long len,
956 unsigned long pgoff, unsigned long flags,
957 struct drm_vma_offset_manager *mgr)
958 {
959 unsigned long addr;
960 unsigned long inflated_addr;
961 struct drm_vma_offset_node *node;
962
963 if (len > TASK_SIZE)
964 return -ENOMEM;
965
966 /*
967 * @pgoff is the file page-offset the huge page boundaries of
968 * which typically aligns to physical address huge page boundaries.
969 * That's not true for DRM, however, where physical address huge
970 * page boundaries instead are aligned with the offset from
971 * buffer object start. So adjust @pgoff to be the offset from
972 * buffer object start.
973 */
974 drm_vma_offset_lock_lookup(mgr);
975 node = drm_vma_offset_lookup_locked(mgr, pgoff, 1);
976 if (node)
977 pgoff -= node->vm_node.start;
978 drm_vma_offset_unlock_lookup(mgr);
979
980 addr = current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
981 if (IS_ERR_VALUE(addr))
982 return addr;
983 if (addr & ~PAGE_MASK)
984 return addr;
985 if (addr > TASK_SIZE - len)
986 return addr;
987
988 if (len < HPAGE_PMD_SIZE)
989 return addr;
990 if (flags & MAP_FIXED)
991 return addr;
992 /*
993 * Our priority is to support MAP_SHARED mapped hugely;
994 * and support MAP_PRIVATE mapped hugely too, until it is COWed.
995 * But if caller specified an address hint, respect that as before.
996 */
997 if (uaddr)
998 return addr;
999
1000 inflated_addr = drm_addr_inflate(addr, len, pgoff, flags,
1001 HPAGE_PMD_SIZE);
1002
1003 if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) &&
1004 len >= HPAGE_PUD_SIZE)
1005 inflated_addr = drm_addr_inflate(inflated_addr, len, pgoff,
1006 flags, HPAGE_PUD_SIZE);
1007 return inflated_addr;
1008 }
1009 #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)1010 unsigned long drm_get_unmapped_area(struct file *file,
1011 unsigned long uaddr, unsigned long len,
1012 unsigned long pgoff, unsigned long flags,
1013 struct drm_vma_offset_manager *mgr)
1014 {
1015 return current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
1016 }
1017 #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1018 EXPORT_SYMBOL_GPL(drm_get_unmapped_area);
1019 #endif /* CONFIG_MMU */
1020