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/smp_lock.h>
40
41 static int drm_open_helper(struct inode *inode, struct file *filp,
42 struct drm_device * dev);
43
drm_setup(struct drm_device * dev)44 static int drm_setup(struct drm_device * dev)
45 {
46 int i;
47 int ret;
48
49 if (dev->driver->firstopen) {
50 ret = dev->driver->firstopen(dev);
51 if (ret != 0)
52 return ret;
53 }
54
55 atomic_set(&dev->ioctl_count, 0);
56 atomic_set(&dev->vma_count, 0);
57
58 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
59 !drm_core_check_feature(dev, DRIVER_MODESET)) {
60 dev->buf_use = 0;
61 atomic_set(&dev->buf_alloc, 0);
62
63 i = drm_dma_setup(dev);
64 if (i < 0)
65 return i;
66 }
67
68 for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
69 atomic_set(&dev->counts[i], 0);
70
71 dev->sigdata.lock = NULL;
72
73 dev->queue_count = 0;
74 dev->queue_reserved = 0;
75 dev->queue_slots = 0;
76 dev->queuelist = NULL;
77 dev->context_flag = 0;
78 dev->interrupt_flag = 0;
79 dev->dma_flag = 0;
80 dev->last_context = 0;
81 dev->last_switch = 0;
82 dev->last_checked = 0;
83 init_waitqueue_head(&dev->context_wait);
84 dev->if_version = 0;
85
86 dev->ctx_start = 0;
87 dev->lck_start = 0;
88
89 dev->buf_async = NULL;
90 init_waitqueue_head(&dev->buf_readers);
91 init_waitqueue_head(&dev->buf_writers);
92
93 DRM_DEBUG("\n");
94
95 /*
96 * The kernel's context could be created here, but is now created
97 * in drm_dma_enqueue. This is more resource-efficient for
98 * hardware that does not do DMA, but may mean that
99 * drm_select_queue fails between the time the interrupt is
100 * initialized and the time the queues are initialized.
101 */
102
103 return 0;
104 }
105
106 /**
107 * Open file.
108 *
109 * \param inode device inode
110 * \param filp file pointer.
111 * \return zero on success or a negative number on failure.
112 *
113 * Searches the DRM device with the same minor number, calls open_helper(), and
114 * increments the device open count. If the open count was previous at zero,
115 * i.e., it's the first that the device is open, then calls setup().
116 */
drm_open(struct inode * inode,struct file * filp)117 int drm_open(struct inode *inode, struct file *filp)
118 {
119 struct drm_device *dev = NULL;
120 int minor_id = iminor(inode);
121 struct drm_minor *minor;
122 int retcode = 0;
123
124 minor = idr_find(&drm_minors_idr, minor_id);
125 if (!minor)
126 return -ENODEV;
127
128 if (!(dev = minor->dev))
129 return -ENODEV;
130
131 retcode = drm_open_helper(inode, filp, dev);
132 if (!retcode) {
133 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
134 spin_lock(&dev->count_lock);
135 if (!dev->open_count++) {
136 spin_unlock(&dev->count_lock);
137 retcode = drm_setup(dev);
138 goto out;
139 }
140 spin_unlock(&dev->count_lock);
141 }
142 out:
143 mutex_lock(&dev->struct_mutex);
144 if (minor->type == DRM_MINOR_LEGACY) {
145 BUG_ON((dev->dev_mapping != NULL) &&
146 (dev->dev_mapping != inode->i_mapping));
147 if (dev->dev_mapping == NULL)
148 dev->dev_mapping = inode->i_mapping;
149 }
150 mutex_unlock(&dev->struct_mutex);
151
152 return retcode;
153 }
154 EXPORT_SYMBOL(drm_open);
155
156 /**
157 * File \c open operation.
158 *
159 * \param inode device inode.
160 * \param filp file pointer.
161 *
162 * Puts the dev->fops corresponding to the device minor number into
163 * \p filp, call the \c open method, and restore the file operations.
164 */
drm_stub_open(struct inode * inode,struct file * filp)165 int drm_stub_open(struct inode *inode, struct file *filp)
166 {
167 struct drm_device *dev = NULL;
168 struct drm_minor *minor;
169 int minor_id = iminor(inode);
170 int err = -ENODEV;
171 const struct file_operations *old_fops;
172
173 DRM_DEBUG("\n");
174
175 /* BKL pushdown: note that nothing else serializes idr_find() */
176 lock_kernel();
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 unlock_kernel();
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 */
drm_cpu_valid(void)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 */
drm_open_helper(struct inode * inode,struct file * filp,struct drm_device * dev)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 = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
244 if (!priv)
245 return -ENOMEM;
246
247 memset(priv, 0, sizeof(*priv));
248 filp->private_data = priv;
249 priv->filp = filp;
250 priv->uid = current_euid();
251 priv->pid = task_pid_nr(current);
252 priv->minor = idr_find(&drm_minors_idr, minor_id);
253 priv->ioctl_count = 0;
254 /* for compatibility root is always authenticated */
255 priv->authenticated = capable(CAP_SYS_ADMIN);
256 priv->lock_count = 0;
257
258 INIT_LIST_HEAD(&priv->lhead);
259 INIT_LIST_HEAD(&priv->fbs);
260
261 if (dev->driver->driver_features & DRIVER_GEM)
262 drm_gem_open(dev, priv);
263
264 if (dev->driver->open) {
265 ret = dev->driver->open(dev, priv);
266 if (ret < 0)
267 goto out_free;
268 }
269
270
271 /* if there is no current master make this fd it */
272 mutex_lock(&dev->struct_mutex);
273 if (!priv->minor->master) {
274 /* create a new master */
275 priv->minor->master = drm_master_create(priv->minor);
276 if (!priv->minor->master) {
277 ret = -ENOMEM;
278 goto out_free;
279 }
280
281 priv->is_master = 1;
282 /* take another reference for the copy in the local file priv */
283 priv->master = drm_master_get(priv->minor->master);
284
285 priv->authenticated = 1;
286
287 mutex_unlock(&dev->struct_mutex);
288 if (dev->driver->master_create) {
289 ret = dev->driver->master_create(dev, priv->master);
290 if (ret) {
291 mutex_lock(&dev->struct_mutex);
292 /* drop both references if this fails */
293 drm_master_put(&priv->minor->master);
294 drm_master_put(&priv->master);
295 mutex_unlock(&dev->struct_mutex);
296 goto out_free;
297 }
298 }
299 } else {
300 /* get a reference to the master */
301 priv->master = drm_master_get(priv->minor->master);
302 mutex_unlock(&dev->struct_mutex);
303 }
304
305 mutex_lock(&dev->struct_mutex);
306 list_add(&priv->lhead, &dev->filelist);
307 mutex_unlock(&dev->struct_mutex);
308
309 #ifdef __alpha__
310 /*
311 * Default the hose
312 */
313 if (!dev->hose) {
314 struct pci_dev *pci_dev;
315 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
316 if (pci_dev) {
317 dev->hose = pci_dev->sysdata;
318 pci_dev_put(pci_dev);
319 }
320 if (!dev->hose) {
321 struct pci_bus *b = pci_bus_b(pci_root_buses.next);
322 if (b)
323 dev->hose = b->sysdata;
324 }
325 }
326 #endif
327
328 return 0;
329 out_free:
330 drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
331 filp->private_data = NULL;
332 return ret;
333 }
334
335 /** No-op. */
drm_fasync(int fd,struct file * filp,int on)336 int drm_fasync(int fd, struct file *filp, int on)
337 {
338 struct drm_file *priv = filp->private_data;
339 struct drm_device *dev = priv->minor->dev;
340 int retcode;
341
342 DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
343 (long)old_encode_dev(priv->minor->device));
344 retcode = fasync_helper(fd, filp, on, &dev->buf_async);
345 if (retcode < 0)
346 return retcode;
347 return 0;
348 }
349 EXPORT_SYMBOL(drm_fasync);
350
351 /*
352 * Reclaim locked buffers; note that this may be a bad idea if the current
353 * context doesn't have the hw lock...
354 */
drm_reclaim_locked_buffers(struct drm_device * dev,struct file * f)355 static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f)
356 {
357 struct drm_file *file_priv = f->private_data;
358
359 if (drm_i_have_hw_lock(dev, file_priv)) {
360 dev->driver->reclaim_buffers_locked(dev, file_priv);
361 } else {
362 unsigned long _end = jiffies + 3 * DRM_HZ;
363 int locked = 0;
364
365 drm_idlelock_take(&file_priv->master->lock);
366
367 /*
368 * Wait for a while.
369 */
370 do {
371 spin_lock_bh(&file_priv->master->lock.spinlock);
372 locked = file_priv->master->lock.idle_has_lock;
373 spin_unlock_bh(&file_priv->master->lock.spinlock);
374 if (locked)
375 break;
376 schedule();
377 } while (!time_after_eq(jiffies, _end));
378
379 if (!locked) {
380 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
381 "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
382 "\tI will go on reclaiming the buffers anyway.\n");
383 }
384
385 dev->driver->reclaim_buffers_locked(dev, file_priv);
386 drm_idlelock_release(&file_priv->master->lock);
387 }
388 }
389
drm_master_release(struct drm_device * dev,struct file * filp)390 static void drm_master_release(struct drm_device *dev, struct file *filp)
391 {
392 struct drm_file *file_priv = filp->private_data;
393
394 if (dev->driver->reclaim_buffers_locked &&
395 file_priv->master->lock.hw_lock)
396 drm_reclaim_locked_buffers(dev, filp);
397
398 if (dev->driver->reclaim_buffers_idlelocked &&
399 file_priv->master->lock.hw_lock) {
400 drm_idlelock_take(&file_priv->master->lock);
401 dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
402 drm_idlelock_release(&file_priv->master->lock);
403 }
404
405
406 if (drm_i_have_hw_lock(dev, file_priv)) {
407 DRM_DEBUG("File %p released, freeing lock for context %d\n",
408 filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
409 drm_lock_free(&file_priv->master->lock,
410 _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
411 }
412
413 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
414 !dev->driver->reclaim_buffers_locked) {
415 dev->driver->reclaim_buffers(dev, file_priv);
416 }
417 }
418
419 /**
420 * Release file.
421 *
422 * \param inode device inode
423 * \param file_priv DRM file private.
424 * \return zero on success or a negative number on failure.
425 *
426 * If the hardware lock is held then free it, and take it again for the kernel
427 * context since it's necessary to reclaim buffers. Unlink the file private
428 * data from its list and free it. Decreases the open count and if it reaches
429 * zero calls drm_lastclose().
430 */
drm_release(struct inode * inode,struct file * filp)431 int drm_release(struct inode *inode, struct file *filp)
432 {
433 struct drm_file *file_priv = filp->private_data;
434 struct drm_device *dev = file_priv->minor->dev;
435 int retcode = 0;
436
437 lock_kernel();
438
439 DRM_DEBUG("open_count = %d\n", dev->open_count);
440
441 if (dev->driver->preclose)
442 dev->driver->preclose(dev, file_priv);
443
444 /* ========================================================
445 * Begin inline drm_release
446 */
447
448 DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
449 task_pid_nr(current),
450 (long)old_encode_dev(file_priv->minor->device),
451 dev->open_count);
452
453 /* if the master has gone away we can't do anything with the lock */
454 if (file_priv->minor->master)
455 drm_master_release(dev, filp);
456
457 if (dev->driver->driver_features & DRIVER_GEM)
458 drm_gem_release(dev, file_priv);
459
460 if (dev->driver->driver_features & DRIVER_MODESET)
461 drm_fb_release(file_priv);
462
463 mutex_lock(&dev->ctxlist_mutex);
464 if (!list_empty(&dev->ctxlist)) {
465 struct drm_ctx_list *pos, *n;
466
467 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
468 if (pos->tag == file_priv &&
469 pos->handle != DRM_KERNEL_CONTEXT) {
470 if (dev->driver->context_dtor)
471 dev->driver->context_dtor(dev,
472 pos->handle);
473
474 drm_ctxbitmap_free(dev, pos->handle);
475
476 list_del(&pos->head);
477 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
478 --dev->ctx_count;
479 }
480 }
481 }
482 mutex_unlock(&dev->ctxlist_mutex);
483
484 mutex_lock(&dev->struct_mutex);
485
486 if (file_priv->is_master) {
487 struct drm_master *master = file_priv->master;
488 struct drm_file *temp;
489 list_for_each_entry(temp, &dev->filelist, lhead) {
490 if ((temp->master == file_priv->master) &&
491 (temp != file_priv))
492 temp->authenticated = 0;
493 }
494
495 /**
496 * Since the master is disappearing, so is the
497 * possibility to lock.
498 */
499
500 if (master->lock.hw_lock) {
501 if (dev->sigdata.lock == master->lock.hw_lock)
502 dev->sigdata.lock = NULL;
503 master->lock.hw_lock = NULL;
504 master->lock.file_priv = NULL;
505 wake_up_interruptible_all(&master->lock.lock_queue);
506 }
507
508 if (file_priv->minor->master == file_priv->master) {
509 /* drop the reference held my the minor */
510 drm_master_put(&file_priv->minor->master);
511 }
512 }
513
514 /* drop the reference held my the file priv */
515 drm_master_put(&file_priv->master);
516 file_priv->is_master = 0;
517 list_del(&file_priv->lhead);
518 mutex_unlock(&dev->struct_mutex);
519
520 if (dev->driver->postclose)
521 dev->driver->postclose(dev, file_priv);
522 drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES);
523
524 /* ========================================================
525 * End inline drm_release
526 */
527
528 atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
529 spin_lock(&dev->count_lock);
530 if (!--dev->open_count) {
531 if (atomic_read(&dev->ioctl_count)) {
532 DRM_ERROR("Device busy: %d\n",
533 atomic_read(&dev->ioctl_count));
534 spin_unlock(&dev->count_lock);
535 unlock_kernel();
536 return -EBUSY;
537 }
538 spin_unlock(&dev->count_lock);
539 unlock_kernel();
540 return drm_lastclose(dev);
541 }
542 spin_unlock(&dev->count_lock);
543
544 unlock_kernel();
545
546 return retcode;
547 }
548 EXPORT_SYMBOL(drm_release);
549
550 /** No-op. */
drm_poll(struct file * filp,struct poll_table_struct * wait)551 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
552 {
553 return 0;
554 }
555 EXPORT_SYMBOL(drm_poll);
556