1 /**
2 * \file drm_fops.c
3 * File operations for DRM
4 *
5 * \author Rickard E. (Rik) Faith <faith@valinux.com>
6 * \author Daryll Strauss <daryll@valinux.com>
7 * \author Gareth Hughes <gareth@valinux.com>
8 */
9
10 /*
11 * Created: Mon Jan 4 08:58:31 1999 by faith@valinux.com
12 *
13 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
14 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
15 * All Rights Reserved.
16 *
17 * Permission is hereby granted, free of charge, to any person obtaining a
18 * copy of this software and associated documentation files (the "Software"),
19 * to deal in the Software without restriction, including without limitation
20 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
21 * and/or sell copies of the Software, and to permit persons to whom the
22 * Software is furnished to do so, subject to the following conditions:
23 *
24 * The above copyright notice and this permission notice (including the next
25 * paragraph) shall be included in all copies or substantial portions of the
26 * Software.
27 *
28 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
29 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
30 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
31 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
32 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
33 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
34 * OTHER DEALINGS IN THE SOFTWARE.
35 */
36
37 #include <drm/drmP.h>
38 #include <linux/poll.h>
39 #include <linux/slab.h>
40 #include <linux/module.h>
41 #include "drm_legacy.h"
42 #include "drm_internal.h"
43
44 /* from BKL pushdown */
45 DEFINE_MUTEX(drm_global_mutex);
46
47 static int drm_open_helper(struct file *filp, struct drm_minor *minor);
48
drm_setup(struct drm_device * dev)49 static int drm_setup(struct drm_device * dev)
50 {
51 int ret;
52
53 if (dev->driver->firstopen &&
54 !drm_core_check_feature(dev, DRIVER_MODESET)) {
55 ret = dev->driver->firstopen(dev);
56 if (ret != 0)
57 return ret;
58 }
59
60 ret = drm_legacy_dma_setup(dev);
61 if (ret < 0)
62 return ret;
63
64
65 DRM_DEBUG("\n");
66 return 0;
67 }
68
69 /**
70 * Open file.
71 *
72 * \param inode device inode
73 * \param filp file pointer.
74 * \return zero on success or a negative number on failure.
75 *
76 * Searches the DRM device with the same minor number, calls open_helper(), and
77 * increments the device open count. If the open count was previous at zero,
78 * i.e., it's the first that the device is open, then calls setup().
79 */
drm_open(struct inode * inode,struct file * filp)80 int drm_open(struct inode *inode, struct file *filp)
81 {
82 struct drm_device *dev;
83 struct drm_minor *minor;
84 int retcode;
85 int need_setup = 0;
86
87 minor = drm_minor_acquire(iminor(inode));
88 if (IS_ERR(minor))
89 return PTR_ERR(minor);
90
91 dev = minor->dev;
92 if (!dev->open_count++)
93 need_setup = 1;
94
95 /* share address_space across all char-devs of a single device */
96 filp->f_mapping = dev->anon_inode->i_mapping;
97
98 retcode = drm_open_helper(filp, minor);
99 if (retcode)
100 goto err_undo;
101 if (need_setup) {
102 retcode = drm_setup(dev);
103 if (retcode)
104 goto err_undo;
105 }
106 return 0;
107
108 err_undo:
109 dev->open_count--;
110 drm_minor_release(minor);
111 return retcode;
112 }
113 EXPORT_SYMBOL(drm_open);
114
115 /**
116 * Check whether DRI will run on this CPU.
117 *
118 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
119 */
drm_cpu_valid(void)120 static int drm_cpu_valid(void)
121 {
122 #if defined(__sparc__) && !defined(__sparc_v9__)
123 return 0; /* No cmpxchg before v9 sparc. */
124 #endif
125 return 1;
126 }
127
128 /**
129 * drm_new_set_master - Allocate a new master object and become master for the
130 * associated master realm.
131 *
132 * @dev: The associated device.
133 * @fpriv: File private identifying the client.
134 *
135 * This function must be called with dev::struct_mutex held.
136 * Returns negative error code on failure. Zero on success.
137 */
drm_new_set_master(struct drm_device * dev,struct drm_file * fpriv)138 int drm_new_set_master(struct drm_device *dev, struct drm_file *fpriv)
139 {
140 struct drm_master *old_master;
141 int ret;
142
143 lockdep_assert_held_once(&dev->master_mutex);
144
145 /* create a new master */
146 fpriv->minor->master = drm_master_create(fpriv->minor);
147 if (!fpriv->minor->master)
148 return -ENOMEM;
149
150 /* take another reference for the copy in the local file priv */
151 old_master = fpriv->master;
152 fpriv->master = drm_master_get(fpriv->minor->master);
153
154 if (dev->driver->master_create) {
155 ret = dev->driver->master_create(dev, fpriv->master);
156 if (ret)
157 goto out_err;
158 }
159 if (dev->driver->master_set) {
160 ret = dev->driver->master_set(dev, fpriv, true);
161 if (ret)
162 goto out_err;
163 }
164
165 fpriv->is_master = 1;
166 fpriv->allowed_master = 1;
167 fpriv->authenticated = 1;
168 if (old_master)
169 drm_master_put(&old_master);
170
171 return 0;
172
173 out_err:
174 /* drop both references and restore old master on failure */
175 drm_master_put(&fpriv->minor->master);
176 drm_master_put(&fpriv->master);
177 fpriv->master = old_master;
178
179 return ret;
180 }
181
182 /**
183 * Called whenever a process opens /dev/drm.
184 *
185 * \param filp file pointer.
186 * \param minor acquired minor-object.
187 * \return zero on success or a negative number on failure.
188 *
189 * Creates and initializes a drm_file structure for the file private data in \p
190 * filp and add it into the double linked list in \p dev.
191 */
drm_open_helper(struct file * filp,struct drm_minor * minor)192 static int drm_open_helper(struct file *filp, struct drm_minor *minor)
193 {
194 struct drm_device *dev = minor->dev;
195 struct drm_file *priv;
196 int ret;
197
198 if (filp->f_flags & O_EXCL)
199 return -EBUSY; /* No exclusive opens */
200 if (!drm_cpu_valid())
201 return -EINVAL;
202 if (dev->switch_power_state != DRM_SWITCH_POWER_ON && dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
203 return -EINVAL;
204
205 DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor->index);
206
207 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
208 if (!priv)
209 return -ENOMEM;
210
211 filp->private_data = priv;
212 filp->f_mode |= FMODE_UNSIGNED_OFFSET;
213 priv->filp = filp;
214 priv->uid = current_euid();
215 priv->pid = get_pid(task_pid(current));
216 priv->minor = minor;
217
218 /* for compatibility root is always authenticated */
219 priv->authenticated = capable(CAP_SYS_ADMIN);
220 priv->lock_count = 0;
221
222 INIT_LIST_HEAD(&priv->lhead);
223 INIT_LIST_HEAD(&priv->fbs);
224 mutex_init(&priv->fbs_lock);
225 INIT_LIST_HEAD(&priv->blobs);
226 INIT_LIST_HEAD(&priv->event_list);
227 init_waitqueue_head(&priv->event_wait);
228 priv->event_space = 4096; /* set aside 4k for event buffer */
229
230 if (drm_core_check_feature(dev, DRIVER_GEM))
231 drm_gem_open(dev, priv);
232
233 if (drm_core_check_feature(dev, DRIVER_PRIME))
234 drm_prime_init_file_private(&priv->prime);
235
236 if (dev->driver->open) {
237 ret = dev->driver->open(dev, priv);
238 if (ret < 0)
239 goto out_prime_destroy;
240 }
241
242 /* if there is no current master make this fd it, but do not create
243 * any master object for render clients */
244 mutex_lock(&dev->master_mutex);
245 if (drm_is_primary_client(priv) && !priv->minor->master) {
246 /* create a new master */
247 ret = drm_new_set_master(dev, priv);
248 if (ret)
249 goto out_close;
250 } else if (drm_is_primary_client(priv)) {
251 /* get a reference to the master */
252 priv->master = drm_master_get(priv->minor->master);
253 }
254 mutex_unlock(&dev->master_mutex);
255
256 mutex_lock(&dev->struct_mutex);
257 list_add(&priv->lhead, &dev->filelist);
258 mutex_unlock(&dev->struct_mutex);
259
260 #ifdef __alpha__
261 /*
262 * Default the hose
263 */
264 if (!dev->hose) {
265 struct pci_dev *pci_dev;
266 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
267 if (pci_dev) {
268 dev->hose = pci_dev->sysdata;
269 pci_dev_put(pci_dev);
270 }
271 if (!dev->hose) {
272 struct pci_bus *b = list_entry(pci_root_buses.next,
273 struct pci_bus, node);
274 if (b)
275 dev->hose = b->sysdata;
276 }
277 }
278 #endif
279
280 return 0;
281
282 out_close:
283 mutex_unlock(&dev->master_mutex);
284 if (dev->driver->postclose)
285 dev->driver->postclose(dev, priv);
286 out_prime_destroy:
287 if (drm_core_check_feature(dev, DRIVER_PRIME))
288 drm_prime_destroy_file_private(&priv->prime);
289 if (drm_core_check_feature(dev, DRIVER_GEM))
290 drm_gem_release(dev, priv);
291 put_pid(priv->pid);
292 kfree(priv);
293 filp->private_data = NULL;
294 return ret;
295 }
296
drm_master_release(struct drm_device * dev,struct file * filp)297 static void drm_master_release(struct drm_device *dev, struct file *filp)
298 {
299 struct drm_file *file_priv = filp->private_data;
300
301 if (drm_legacy_i_have_hw_lock(dev, file_priv)) {
302 DRM_DEBUG("File %p released, freeing lock for context %d\n",
303 filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
304 drm_legacy_lock_free(&file_priv->master->lock,
305 _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
306 }
307 }
308
drm_events_release(struct drm_file * file_priv)309 static void drm_events_release(struct drm_file *file_priv)
310 {
311 struct drm_device *dev = file_priv->minor->dev;
312 struct drm_pending_event *e, *et;
313 struct drm_pending_vblank_event *v, *vt;
314 unsigned long flags;
315
316 spin_lock_irqsave(&dev->event_lock, flags);
317
318 /* Remove pending flips */
319 list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link)
320 if (v->base.file_priv == file_priv) {
321 list_del(&v->base.link);
322 drm_vblank_put(dev, v->pipe);
323 v->base.destroy(&v->base);
324 }
325
326 /* Remove unconsumed events */
327 list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
328 list_del(&e->link);
329 e->destroy(e);
330 }
331
332 spin_unlock_irqrestore(&dev->event_lock, flags);
333 }
334
335 /**
336 * drm_legacy_dev_reinit
337 *
338 * Reinitializes a legacy/ums drm device in it's lastclose function.
339 */
drm_legacy_dev_reinit(struct drm_device * dev)340 static void drm_legacy_dev_reinit(struct drm_device *dev)
341 {
342 if (drm_core_check_feature(dev, DRIVER_MODESET))
343 return;
344
345 dev->sigdata.lock = NULL;
346
347 dev->context_flag = 0;
348 dev->last_context = 0;
349 dev->if_version = 0;
350 }
351
352 /**
353 * Take down the DRM device.
354 *
355 * \param dev DRM device structure.
356 *
357 * Frees every resource in \p dev.
358 *
359 * \sa drm_device
360 */
drm_lastclose(struct drm_device * dev)361 int drm_lastclose(struct drm_device * dev)
362 {
363 DRM_DEBUG("\n");
364
365 if (dev->driver->lastclose)
366 dev->driver->lastclose(dev);
367 DRM_DEBUG("driver lastclose completed\n");
368
369 if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
370 drm_irq_uninstall(dev);
371
372 mutex_lock(&dev->struct_mutex);
373
374 drm_agp_clear(dev);
375
376 drm_legacy_sg_cleanup(dev);
377 drm_legacy_vma_flush(dev);
378 drm_legacy_dma_takedown(dev);
379
380 mutex_unlock(&dev->struct_mutex);
381
382 drm_legacy_dev_reinit(dev);
383
384 DRM_DEBUG("lastclose completed\n");
385 return 0;
386 }
387
388 /**
389 * Release file.
390 *
391 * \param inode device inode
392 * \param file_priv DRM file private.
393 * \return zero on success or a negative number on failure.
394 *
395 * If the hardware lock is held then free it, and take it again for the kernel
396 * context since it's necessary to reclaim buffers. Unlink the file private
397 * data from its list and free it. Decreases the open count and if it reaches
398 * zero calls drm_lastclose().
399 */
drm_release(struct inode * inode,struct file * filp)400 int drm_release(struct inode *inode, struct file *filp)
401 {
402 struct drm_file *file_priv = filp->private_data;
403 struct drm_minor *minor = file_priv->minor;
404 struct drm_device *dev = minor->dev;
405 int retcode = 0;
406
407 mutex_lock(&drm_global_mutex);
408
409 DRM_DEBUG("open_count = %d\n", dev->open_count);
410
411 mutex_lock(&dev->struct_mutex);
412 list_del(&file_priv->lhead);
413 if (file_priv->magic)
414 idr_remove(&file_priv->master->magic_map, file_priv->magic);
415 mutex_unlock(&dev->struct_mutex);
416
417 if (dev->driver->preclose)
418 dev->driver->preclose(dev, file_priv);
419
420 /* ========================================================
421 * Begin inline drm_release
422 */
423
424 DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
425 task_pid_nr(current),
426 (long)old_encode_dev(file_priv->minor->kdev->devt),
427 dev->open_count);
428
429 /* if the master has gone away we can't do anything with the lock */
430 if (file_priv->minor->master)
431 drm_master_release(dev, filp);
432
433 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
434 drm_legacy_reclaim_buffers(dev, file_priv);
435
436 drm_events_release(file_priv);
437
438 if (drm_core_check_feature(dev, DRIVER_MODESET)) {
439 drm_fb_release(file_priv);
440 drm_property_destroy_user_blobs(dev, file_priv);
441 }
442
443 if (drm_core_check_feature(dev, DRIVER_GEM))
444 drm_gem_release(dev, file_priv);
445
446 drm_legacy_ctxbitmap_flush(dev, file_priv);
447
448 mutex_lock(&dev->master_mutex);
449
450 if (file_priv->is_master) {
451 struct drm_master *master = file_priv->master;
452
453 /**
454 * Since the master is disappearing, so is the
455 * possibility to lock.
456 */
457 mutex_lock(&dev->struct_mutex);
458 if (master->lock.hw_lock) {
459 if (dev->sigdata.lock == master->lock.hw_lock)
460 dev->sigdata.lock = NULL;
461 master->lock.hw_lock = NULL;
462 master->lock.file_priv = NULL;
463 wake_up_interruptible_all(&master->lock.lock_queue);
464 }
465 mutex_unlock(&dev->struct_mutex);
466
467 if (file_priv->minor->master == file_priv->master) {
468 /* drop the reference held my the minor */
469 if (dev->driver->master_drop)
470 dev->driver->master_drop(dev, file_priv, true);
471 drm_master_put(&file_priv->minor->master);
472 }
473 }
474
475 /* drop the master reference held by the file priv */
476 if (file_priv->master)
477 drm_master_put(&file_priv->master);
478 file_priv->is_master = 0;
479 mutex_unlock(&dev->master_mutex);
480
481 if (dev->driver->postclose)
482 dev->driver->postclose(dev, file_priv);
483
484
485 if (drm_core_check_feature(dev, DRIVER_PRIME))
486 drm_prime_destroy_file_private(&file_priv->prime);
487
488 WARN_ON(!list_empty(&file_priv->event_list));
489
490 put_pid(file_priv->pid);
491 kfree(file_priv);
492
493 /* ========================================================
494 * End inline drm_release
495 */
496
497 if (!--dev->open_count) {
498 retcode = drm_lastclose(dev);
499 if (drm_device_is_unplugged(dev))
500 drm_put_dev(dev);
501 }
502 mutex_unlock(&drm_global_mutex);
503
504 drm_minor_release(minor);
505
506 return retcode;
507 }
508 EXPORT_SYMBOL(drm_release);
509
drm_read(struct file * filp,char __user * buffer,size_t count,loff_t * offset)510 ssize_t drm_read(struct file *filp, char __user *buffer,
511 size_t count, loff_t *offset)
512 {
513 struct drm_file *file_priv = filp->private_data;
514 struct drm_device *dev = file_priv->minor->dev;
515 ssize_t ret = 0;
516
517 if (!access_ok(VERIFY_WRITE, buffer, count))
518 return -EFAULT;
519
520 spin_lock_irq(&dev->event_lock);
521 for (;;) {
522 if (list_empty(&file_priv->event_list)) {
523 if (ret)
524 break;
525
526 if (filp->f_flags & O_NONBLOCK) {
527 ret = -EAGAIN;
528 break;
529 }
530
531 spin_unlock_irq(&dev->event_lock);
532 ret = wait_event_interruptible(file_priv->event_wait,
533 !list_empty(&file_priv->event_list));
534 spin_lock_irq(&dev->event_lock);
535 if (ret < 0)
536 break;
537
538 ret = 0;
539 } else {
540 struct drm_pending_event *e;
541
542 e = list_first_entry(&file_priv->event_list,
543 struct drm_pending_event, link);
544 if (e->event->length + ret > count)
545 break;
546
547 if (__copy_to_user_inatomic(buffer + ret,
548 e->event, e->event->length)) {
549 if (ret == 0)
550 ret = -EFAULT;
551 break;
552 }
553
554 file_priv->event_space += e->event->length;
555 ret += e->event->length;
556 list_del(&e->link);
557 e->destroy(e);
558 }
559 }
560 spin_unlock_irq(&dev->event_lock);
561
562 return ret;
563 }
564 EXPORT_SYMBOL(drm_read);
565
drm_poll(struct file * filp,struct poll_table_struct * wait)566 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
567 {
568 struct drm_file *file_priv = filp->private_data;
569 unsigned int mask = 0;
570
571 poll_wait(filp, &file_priv->event_wait, wait);
572
573 if (!list_empty(&file_priv->event_list))
574 mask |= POLLIN | POLLRDNORM;
575
576 return mask;
577 }
578 EXPORT_SYMBOL(drm_poll);
579