Merge branch 'drm-intel-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ickle...
[pandora-kernel.git] / drivers / gpu / drm / drm_fops.c
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 "drmP.h"
38 #include <linux/poll.h>
39 #include <linux/slab.h>
40 #include <linux/smp_lock.h>
41
42 /* from BKL pushdown: note that nothing else serializes idr_find() */
43 DEFINE_MUTEX(drm_global_mutex);
44 EXPORT_SYMBOL(drm_global_mutex);
45
46 static int drm_open_helper(struct inode *inode, struct file *filp,
47                            struct drm_device * dev);
48
49 static int drm_setup(struct drm_device * dev)
50 {
51         int i;
52         int ret;
53
54         if (dev->driver->firstopen) {
55                 ret = dev->driver->firstopen(dev);
56                 if (ret != 0)
57                         return ret;
58         }
59
60         atomic_set(&dev->ioctl_count, 0);
61         atomic_set(&dev->vma_count, 0);
62
63         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
64             !drm_core_check_feature(dev, DRIVER_MODESET)) {
65                 dev->buf_use = 0;
66                 atomic_set(&dev->buf_alloc, 0);
67
68                 i = drm_dma_setup(dev);
69                 if (i < 0)
70                         return i;
71         }
72
73         for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
74                 atomic_set(&dev->counts[i], 0);
75
76         dev->sigdata.lock = NULL;
77
78         dev->queue_count = 0;
79         dev->queue_reserved = 0;
80         dev->queue_slots = 0;
81         dev->queuelist = NULL;
82         dev->context_flag = 0;
83         dev->interrupt_flag = 0;
84         dev->dma_flag = 0;
85         dev->last_context = 0;
86         dev->last_switch = 0;
87         dev->last_checked = 0;
88         init_waitqueue_head(&dev->context_wait);
89         dev->if_version = 0;
90
91         dev->ctx_start = 0;
92         dev->lck_start = 0;
93
94         dev->buf_async = NULL;
95         init_waitqueue_head(&dev->buf_readers);
96         init_waitqueue_head(&dev->buf_writers);
97
98         DRM_DEBUG("\n");
99
100         /*
101          * The kernel's context could be created here, but is now created
102          * in drm_dma_enqueue.  This is more resource-efficient for
103          * hardware that does not do DMA, but may mean that
104          * drm_select_queue fails between the time the interrupt is
105          * initialized and the time the queues are initialized.
106          */
107
108         return 0;
109 }
110
111 /**
112  * Open file.
113  *
114  * \param inode device inode
115  * \param filp file pointer.
116  * \return zero on success or a negative number on failure.
117  *
118  * Searches the DRM device with the same minor number, calls open_helper(), and
119  * increments the device open count. If the open count was previous at zero,
120  * i.e., it's the first that the device is open, then calls setup().
121  */
122 int drm_open(struct inode *inode, struct file *filp)
123 {
124         struct drm_device *dev = NULL;
125         int minor_id = iminor(inode);
126         struct drm_minor *minor;
127         int retcode = 0;
128
129         minor = idr_find(&drm_minors_idr, minor_id);
130         if (!minor)
131                 return -ENODEV;
132
133         if (!(dev = minor->dev))
134                 return -ENODEV;
135
136         retcode = drm_open_helper(inode, filp, dev);
137         if (!retcode) {
138                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
139                 if (!dev->open_count++)
140                         retcode = drm_setup(dev);
141         }
142         if (!retcode) {
143                 mutex_lock(&dev->struct_mutex);
144                 if (minor->type == DRM_MINOR_LEGACY) {
145                         if (dev->dev_mapping == NULL)
146                                 dev->dev_mapping = inode->i_mapping;
147                         else if (dev->dev_mapping != inode->i_mapping)
148                                 retcode = -ENODEV;
149                 }
150                 mutex_unlock(&dev->struct_mutex);
151         }
152
153         return retcode;
154 }
155 EXPORT_SYMBOL(drm_open);
156
157 /**
158  * File \c open operation.
159  *
160  * \param inode device inode.
161  * \param filp file pointer.
162  *
163  * Puts the dev->fops corresponding to the device minor number into
164  * \p filp, call the \c open method, and restore the file operations.
165  */
166 int drm_stub_open(struct inode *inode, struct file *filp)
167 {
168         struct drm_device *dev = NULL;
169         struct drm_minor *minor;
170         int minor_id = iminor(inode);
171         int err = -ENODEV;
172         const struct file_operations *old_fops;
173
174         DRM_DEBUG("\n");
175
176         mutex_lock(&drm_global_mutex);
177         minor = idr_find(&drm_minors_idr, minor_id);
178         if (!minor)
179                 goto out;
180
181         if (!(dev = minor->dev))
182                 goto out;
183
184         old_fops = filp->f_op;
185         filp->f_op = fops_get(&dev->driver->fops);
186         if (filp->f_op == NULL) {
187                 filp->f_op = old_fops;
188                 goto out;
189         }
190         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
191                 fops_put(filp->f_op);
192                 filp->f_op = fops_get(old_fops);
193         }
194         fops_put(old_fops);
195
196 out:
197         mutex_unlock(&drm_global_mutex);
198         return err;
199 }
200
201 /**
202  * Check whether DRI will run on this CPU.
203  *
204  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
205  */
206 static int drm_cpu_valid(void)
207 {
208 #if defined(__i386__)
209         if (boot_cpu_data.x86 == 3)
210                 return 0;       /* No cmpxchg on a 386 */
211 #endif
212 #if defined(__sparc__) && !defined(__sparc_v9__)
213         return 0;               /* No cmpxchg before v9 sparc. */
214 #endif
215         return 1;
216 }
217
218 /**
219  * Called whenever a process opens /dev/drm.
220  *
221  * \param inode device inode.
222  * \param filp file pointer.
223  * \param dev device.
224  * \return zero on success or a negative number on failure.
225  *
226  * Creates and initializes a drm_file structure for the file private data in \p
227  * filp and add it into the double linked list in \p dev.
228  */
229 static int drm_open_helper(struct inode *inode, struct file *filp,
230                            struct drm_device * dev)
231 {
232         int minor_id = iminor(inode);
233         struct drm_file *priv;
234         int ret;
235
236         if (filp->f_flags & O_EXCL)
237                 return -EBUSY;  /* No exclusive opens */
238         if (!drm_cpu_valid())
239                 return -EINVAL;
240
241         DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id);
242
243         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
244         if (!priv)
245                 return -ENOMEM;
246
247         filp->private_data = priv;
248         priv->filp = filp;
249         priv->uid = current_euid();
250         priv->pid = task_pid_nr(current);
251         priv->minor = idr_find(&drm_minors_idr, minor_id);
252         priv->ioctl_count = 0;
253         /* for compatibility root is always authenticated */
254         priv->authenticated = capable(CAP_SYS_ADMIN);
255         priv->lock_count = 0;
256
257         INIT_LIST_HEAD(&priv->lhead);
258         INIT_LIST_HEAD(&priv->fbs);
259         INIT_LIST_HEAD(&priv->event_list);
260         init_waitqueue_head(&priv->event_wait);
261         priv->event_space = 4096; /* set aside 4k for event buffer */
262
263         if (dev->driver->driver_features & DRIVER_GEM)
264                 drm_gem_open(dev, priv);
265
266         if (dev->driver->open) {
267                 ret = dev->driver->open(dev, priv);
268                 if (ret < 0)
269                         goto out_free;
270         }
271
272
273         /* if there is no current master make this fd it */
274         mutex_lock(&dev->struct_mutex);
275         if (!priv->minor->master) {
276                 /* create a new master */
277                 priv->minor->master = drm_master_create(priv->minor);
278                 if (!priv->minor->master) {
279                         mutex_unlock(&dev->struct_mutex);
280                         ret = -ENOMEM;
281                         goto out_free;
282                 }
283
284                 priv->is_master = 1;
285                 /* take another reference for the copy in the local file priv */
286                 priv->master = drm_master_get(priv->minor->master);
287
288                 priv->authenticated = 1;
289
290                 mutex_unlock(&dev->struct_mutex);
291                 if (dev->driver->master_create) {
292                         ret = dev->driver->master_create(dev, priv->master);
293                         if (ret) {
294                                 mutex_lock(&dev->struct_mutex);
295                                 /* drop both references if this fails */
296                                 drm_master_put(&priv->minor->master);
297                                 drm_master_put(&priv->master);
298                                 mutex_unlock(&dev->struct_mutex);
299                                 goto out_free;
300                         }
301                 }
302                 mutex_lock(&dev->struct_mutex);
303                 if (dev->driver->master_set) {
304                         ret = dev->driver->master_set(dev, priv, true);
305                         if (ret) {
306                                 /* drop both references if this fails */
307                                 drm_master_put(&priv->minor->master);
308                                 drm_master_put(&priv->master);
309                                 mutex_unlock(&dev->struct_mutex);
310                                 goto out_free;
311                         }
312                 }
313                 mutex_unlock(&dev->struct_mutex);
314         } else {
315                 /* get a reference to the master */
316                 priv->master = drm_master_get(priv->minor->master);
317                 mutex_unlock(&dev->struct_mutex);
318         }
319
320         mutex_lock(&dev->struct_mutex);
321         list_add(&priv->lhead, &dev->filelist);
322         mutex_unlock(&dev->struct_mutex);
323
324 #ifdef __alpha__
325         /*
326          * Default the hose
327          */
328         if (!dev->hose) {
329                 struct pci_dev *pci_dev;
330                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
331                 if (pci_dev) {
332                         dev->hose = pci_dev->sysdata;
333                         pci_dev_put(pci_dev);
334                 }
335                 if (!dev->hose) {
336                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
337                         if (b)
338                                 dev->hose = b->sysdata;
339                 }
340         }
341 #endif
342
343         return 0;
344       out_free:
345         kfree(priv);
346         filp->private_data = NULL;
347         return ret;
348 }
349
350 /** No-op. */
351 int drm_fasync(int fd, struct file *filp, int on)
352 {
353         struct drm_file *priv = filp->private_data;
354         struct drm_device *dev = priv->minor->dev;
355
356         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
357                   (long)old_encode_dev(priv->minor->device));
358         return fasync_helper(fd, filp, on, &dev->buf_async);
359 }
360 EXPORT_SYMBOL(drm_fasync);
361
362 /*
363  * Reclaim locked buffers; note that this may be a bad idea if the current
364  * context doesn't have the hw lock...
365  */
366 static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f)
367 {
368         struct drm_file *file_priv = f->private_data;
369
370         if (drm_i_have_hw_lock(dev, file_priv)) {
371                 dev->driver->reclaim_buffers_locked(dev, file_priv);
372         } else {
373                 unsigned long _end = jiffies + 3 * DRM_HZ;
374                 int locked = 0;
375
376                 drm_idlelock_take(&file_priv->master->lock);
377
378                 /*
379                  * Wait for a while.
380                  */
381                 do {
382                         spin_lock_bh(&file_priv->master->lock.spinlock);
383                         locked = file_priv->master->lock.idle_has_lock;
384                         spin_unlock_bh(&file_priv->master->lock.spinlock);
385                         if (locked)
386                                 break;
387                         schedule();
388                 } while (!time_after_eq(jiffies, _end));
389
390                 if (!locked) {
391                         DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
392                                   "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
393                                   "\tI will go on reclaiming the buffers anyway.\n");
394                 }
395
396                 dev->driver->reclaim_buffers_locked(dev, file_priv);
397                 drm_idlelock_release(&file_priv->master->lock);
398         }
399 }
400
401 static void drm_master_release(struct drm_device *dev, struct file *filp)
402 {
403         struct drm_file *file_priv = filp->private_data;
404
405         if (dev->driver->reclaim_buffers_locked &&
406             file_priv->master->lock.hw_lock)
407                 drm_reclaim_locked_buffers(dev, filp);
408
409         if (dev->driver->reclaim_buffers_idlelocked &&
410             file_priv->master->lock.hw_lock) {
411                 drm_idlelock_take(&file_priv->master->lock);
412                 dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
413                 drm_idlelock_release(&file_priv->master->lock);
414         }
415
416
417         if (drm_i_have_hw_lock(dev, file_priv)) {
418                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
419                           filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
420                 drm_lock_free(&file_priv->master->lock,
421                               _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
422         }
423
424         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
425             !dev->driver->reclaim_buffers_locked) {
426                 dev->driver->reclaim_buffers(dev, file_priv);
427         }
428 }
429
430 static void drm_events_release(struct drm_file *file_priv)
431 {
432         struct drm_device *dev = file_priv->minor->dev;
433         struct drm_pending_event *e, *et;
434         struct drm_pending_vblank_event *v, *vt;
435         unsigned long flags;
436
437         spin_lock_irqsave(&dev->event_lock, flags);
438
439         /* Remove pending flips */
440         list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link)
441                 if (v->base.file_priv == file_priv) {
442                         list_del(&v->base.link);
443                         drm_vblank_put(dev, v->pipe);
444                         v->base.destroy(&v->base);
445                 }
446
447         /* Remove unconsumed events */
448         list_for_each_entry_safe(e, et, &file_priv->event_list, link)
449                 e->destroy(e);
450
451         spin_unlock_irqrestore(&dev->event_lock, flags);
452 }
453
454 /**
455  * Release file.
456  *
457  * \param inode device inode
458  * \param file_priv DRM file private.
459  * \return zero on success or a negative number on failure.
460  *
461  * If the hardware lock is held then free it, and take it again for the kernel
462  * context since it's necessary to reclaim buffers. Unlink the file private
463  * data from its list and free it. Decreases the open count and if it reaches
464  * zero calls drm_lastclose().
465  */
466 int drm_release(struct inode *inode, struct file *filp)
467 {
468         struct drm_file *file_priv = filp->private_data;
469         struct drm_device *dev = file_priv->minor->dev;
470         int retcode = 0;
471
472         mutex_lock(&drm_global_mutex);
473
474         DRM_DEBUG("open_count = %d\n", dev->open_count);
475
476         if (dev->driver->preclose)
477                 dev->driver->preclose(dev, file_priv);
478
479         /* ========================================================
480          * Begin inline drm_release
481          */
482
483         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
484                   task_pid_nr(current),
485                   (long)old_encode_dev(file_priv->minor->device),
486                   dev->open_count);
487
488         /* if the master has gone away we can't do anything with the lock */
489         if (file_priv->minor->master)
490                 drm_master_release(dev, filp);
491
492         drm_events_release(file_priv);
493
494         if (dev->driver->driver_features & DRIVER_GEM)
495                 drm_gem_release(dev, file_priv);
496
497         if (dev->driver->driver_features & DRIVER_MODESET)
498                 drm_fb_release(file_priv);
499
500         mutex_lock(&dev->ctxlist_mutex);
501         if (!list_empty(&dev->ctxlist)) {
502                 struct drm_ctx_list *pos, *n;
503
504                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
505                         if (pos->tag == file_priv &&
506                             pos->handle != DRM_KERNEL_CONTEXT) {
507                                 if (dev->driver->context_dtor)
508                                         dev->driver->context_dtor(dev,
509                                                                   pos->handle);
510
511                                 drm_ctxbitmap_free(dev, pos->handle);
512
513                                 list_del(&pos->head);
514                                 kfree(pos);
515                                 --dev->ctx_count;
516                         }
517                 }
518         }
519         mutex_unlock(&dev->ctxlist_mutex);
520
521         mutex_lock(&dev->struct_mutex);
522
523         if (file_priv->is_master) {
524                 struct drm_master *master = file_priv->master;
525                 struct drm_file *temp;
526                 list_for_each_entry(temp, &dev->filelist, lhead) {
527                         if ((temp->master == file_priv->master) &&
528                             (temp != file_priv))
529                                 temp->authenticated = 0;
530                 }
531
532                 /**
533                  * Since the master is disappearing, so is the
534                  * possibility to lock.
535                  */
536
537                 if (master->lock.hw_lock) {
538                         if (dev->sigdata.lock == master->lock.hw_lock)
539                                 dev->sigdata.lock = NULL;
540                         master->lock.hw_lock = NULL;
541                         master->lock.file_priv = NULL;
542                         wake_up_interruptible_all(&master->lock.lock_queue);
543                 }
544
545                 if (file_priv->minor->master == file_priv->master) {
546                         /* drop the reference held my the minor */
547                         if (dev->driver->master_drop)
548                                 dev->driver->master_drop(dev, file_priv, true);
549                         drm_master_put(&file_priv->minor->master);
550                 }
551         }
552
553         /* drop the reference held my the file priv */
554         drm_master_put(&file_priv->master);
555         file_priv->is_master = 0;
556         list_del(&file_priv->lhead);
557         mutex_unlock(&dev->struct_mutex);
558
559         if (dev->driver->postclose)
560                 dev->driver->postclose(dev, file_priv);
561         kfree(file_priv);
562
563         /* ========================================================
564          * End inline drm_release
565          */
566
567         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
568         if (!--dev->open_count) {
569                 if (atomic_read(&dev->ioctl_count)) {
570                         DRM_ERROR("Device busy: %d\n",
571                                   atomic_read(&dev->ioctl_count));
572                         retcode = -EBUSY;
573                 } else
574                         retcode = drm_lastclose(dev);
575         }
576         mutex_unlock(&drm_global_mutex);
577
578         return retcode;
579 }
580 EXPORT_SYMBOL(drm_release);
581
582 static bool
583 drm_dequeue_event(struct drm_file *file_priv,
584                   size_t total, size_t max, struct drm_pending_event **out)
585 {
586         struct drm_device *dev = file_priv->minor->dev;
587         struct drm_pending_event *e;
588         unsigned long flags;
589         bool ret = false;
590
591         spin_lock_irqsave(&dev->event_lock, flags);
592
593         *out = NULL;
594         if (list_empty(&file_priv->event_list))
595                 goto out;
596         e = list_first_entry(&file_priv->event_list,
597                              struct drm_pending_event, link);
598         if (e->event->length + total > max)
599                 goto out;
600
601         file_priv->event_space += e->event->length;
602         list_del(&e->link);
603         *out = e;
604         ret = true;
605
606 out:
607         spin_unlock_irqrestore(&dev->event_lock, flags);
608         return ret;
609 }
610
611 ssize_t drm_read(struct file *filp, char __user *buffer,
612                  size_t count, loff_t *offset)
613 {
614         struct drm_file *file_priv = filp->private_data;
615         struct drm_pending_event *e;
616         size_t total;
617         ssize_t ret;
618
619         ret = wait_event_interruptible(file_priv->event_wait,
620                                        !list_empty(&file_priv->event_list));
621         if (ret < 0)
622                 return ret;
623
624         total = 0;
625         while (drm_dequeue_event(file_priv, total, count, &e)) {
626                 if (copy_to_user(buffer + total,
627                                  e->event, e->event->length)) {
628                         total = -EFAULT;
629                         break;
630                 }
631
632                 total += e->event->length;
633                 e->destroy(e);
634         }
635
636         return total;
637 }
638 EXPORT_SYMBOL(drm_read);
639
640 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
641 {
642         struct drm_file *file_priv = filp->private_data;
643         unsigned int mask = 0;
644
645         poll_wait(filp, &file_priv->event_wait, wait);
646
647         if (!list_empty(&file_priv->event_list))
648                 mask |= POLLIN | POLLRDNORM;
649
650         return mask;
651 }
652 EXPORT_SYMBOL(drm_poll);