Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/shaggy...
[linux-2.6] / drivers / char / 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 "drm_sarea.h"
39 #include <linux/poll.h>
40
41 static int drm_open_helper(struct inode *inode, struct file *filp,
42                            drm_device_t * dev);
43
44 static int drm_setup(drm_device_t * dev)
45 {
46         drm_local_map_t *map;
47         int i;
48         int ret;
49         u32 sareapage;
50
51         if (dev->driver->firstopen) {
52                 ret = dev->driver->firstopen(dev);
53                 if (ret != 0)
54                         return ret;
55         }
56
57         dev->magicfree.next = NULL;
58
59         /* prebuild the SAREA */
60         sareapage = max_t(unsigned, SAREA_MAX, PAGE_SIZE);
61         i = drm_addmap(dev, 0, sareapage, _DRM_SHM, _DRM_CONTAINS_LOCK, &map);
62         if (i != 0)
63                 return i;
64
65         atomic_set(&dev->ioctl_count, 0);
66         atomic_set(&dev->vma_count, 0);
67         dev->buf_use = 0;
68         atomic_set(&dev->buf_alloc, 0);
69
70         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) {
71                 i = drm_dma_setup(dev);
72                 if (i < 0)
73                         return i;
74         }
75
76         for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
77                 atomic_set(&dev->counts[i], 0);
78
79         drm_ht_create(&dev->magiclist, DRM_MAGIC_HASH_ORDER);
80         INIT_LIST_HEAD(&dev->magicfree);
81
82         dev->ctxlist = drm_alloc(sizeof(*dev->ctxlist), DRM_MEM_CTXLIST);
83         if (dev->ctxlist == NULL)
84                 return -ENOMEM;
85         memset(dev->ctxlist, 0, sizeof(*dev->ctxlist));
86         INIT_LIST_HEAD(&dev->ctxlist->head);
87
88         dev->vmalist = NULL;
89         dev->sigdata.lock = NULL;
90         init_waitqueue_head(&dev->lock.lock_queue);
91         dev->queue_count = 0;
92         dev->queue_reserved = 0;
93         dev->queue_slots = 0;
94         dev->queuelist = NULL;
95         dev->irq_enabled = 0;
96         dev->context_flag = 0;
97         dev->interrupt_flag = 0;
98         dev->dma_flag = 0;
99         dev->last_context = 0;
100         dev->last_switch = 0;
101         dev->last_checked = 0;
102         init_waitqueue_head(&dev->context_wait);
103         dev->if_version = 0;
104
105         dev->ctx_start = 0;
106         dev->lck_start = 0;
107
108         dev->buf_async = NULL;
109         init_waitqueue_head(&dev->buf_readers);
110         init_waitqueue_head(&dev->buf_writers);
111
112         DRM_DEBUG("\n");
113
114         /*
115          * The kernel's context could be created here, but is now created
116          * in drm_dma_enqueue.  This is more resource-efficient for
117          * hardware that does not do DMA, but may mean that
118          * drm_select_queue fails between the time the interrupt is
119          * initialized and the time the queues are initialized.
120          */
121
122         return 0;
123 }
124
125 /**
126  * Open file.
127  *
128  * \param inode device inode
129  * \param filp file pointer.
130  * \return zero on success or a negative number on failure.
131  *
132  * Searches the DRM device with the same minor number, calls open_helper(), and
133  * increments the device open count. If the open count was previous at zero,
134  * i.e., it's the first that the device is open, then calls setup().
135  */
136 int drm_open(struct inode *inode, struct file *filp)
137 {
138         drm_device_t *dev = NULL;
139         int minor = iminor(inode);
140         int retcode = 0;
141
142         if (!((minor >= 0) && (minor < drm_cards_limit)))
143                 return -ENODEV;
144
145         if (!drm_heads[minor])
146                 return -ENODEV;
147
148         if (!(dev = drm_heads[minor]->dev))
149                 return -ENODEV;
150
151         retcode = drm_open_helper(inode, filp, dev);
152         if (!retcode) {
153                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
154                 spin_lock(&dev->count_lock);
155                 if (!dev->open_count++) {
156                         spin_unlock(&dev->count_lock);
157                         return drm_setup(dev);
158                 }
159                 spin_unlock(&dev->count_lock);
160         }
161
162         return retcode;
163 }
164 EXPORT_SYMBOL(drm_open);
165
166 /**
167  * File \c open operation.
168  *
169  * \param inode device inode.
170  * \param filp file pointer.
171  *
172  * Puts the dev->fops corresponding to the device minor number into
173  * \p filp, call the \c open method, and restore the file operations.
174  */
175 int drm_stub_open(struct inode *inode, struct file *filp)
176 {
177         drm_device_t *dev = NULL;
178         int minor = iminor(inode);
179         int err = -ENODEV;
180         const struct file_operations *old_fops;
181
182         DRM_DEBUG("\n");
183
184         if (!((minor >= 0) && (minor < drm_cards_limit)))
185                 return -ENODEV;
186
187         if (!drm_heads[minor])
188                 return -ENODEV;
189
190         if (!(dev = drm_heads[minor]->dev))
191                 return -ENODEV;
192
193         old_fops = filp->f_op;
194         filp->f_op = fops_get(&dev->driver->fops);
195         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
196                 fops_put(filp->f_op);
197                 filp->f_op = fops_get(old_fops);
198         }
199         fops_put(old_fops);
200
201         return err;
202 }
203
204 /**
205  * Check whether DRI will run on this CPU.
206  *
207  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
208  */
209 static int drm_cpu_valid(void)
210 {
211 #if defined(__i386__)
212         if (boot_cpu_data.x86 == 3)
213                 return 0;       /* No cmpxchg on a 386 */
214 #endif
215 #if defined(__sparc__) && !defined(__sparc_v9__)
216         return 0;               /* No cmpxchg before v9 sparc. */
217 #endif
218         return 1;
219 }
220
221 /**
222  * Called whenever a process opens /dev/drm.
223  *
224  * \param inode device inode.
225  * \param filp file pointer.
226  * \param dev device.
227  * \return zero on success or a negative number on failure.
228  *
229  * Creates and initializes a drm_file structure for the file private data in \p
230  * filp and add it into the double linked list in \p dev.
231  */
232 static int drm_open_helper(struct inode *inode, struct file *filp,
233                            drm_device_t * dev)
234 {
235         int minor = iminor(inode);
236         drm_file_t *priv;
237         int ret;
238
239         if (filp->f_flags & O_EXCL)
240                 return -EBUSY;  /* No exclusive opens */
241         if (!drm_cpu_valid())
242                 return -EINVAL;
243
244         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
245
246         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
247         if (!priv)
248                 return -ENOMEM;
249
250         memset(priv, 0, sizeof(*priv));
251         filp->private_data = priv;
252         priv->uid = current->euid;
253         priv->pid = current->pid;
254         priv->minor = minor;
255         priv->head = drm_heads[minor];
256         priv->ioctl_count = 0;
257         /* for compatibility root is always authenticated */
258         priv->authenticated = capable(CAP_SYS_ADMIN);
259         priv->lock_count = 0;
260
261         if (dev->driver->open) {
262                 ret = dev->driver->open(dev, priv);
263                 if (ret < 0)
264                         goto out_free;
265         }
266
267         mutex_lock(&dev->struct_mutex);
268         if (!dev->file_last) {
269                 priv->next = NULL;
270                 priv->prev = NULL;
271                 dev->file_first = priv;
272                 dev->file_last = priv;
273                 /* first opener automatically becomes master */
274                 priv->master = 1;
275         } else {
276                 priv->next = NULL;
277                 priv->prev = dev->file_last;
278                 dev->file_last->next = priv;
279                 dev->file_last = priv;
280         }
281         mutex_unlock(&dev->struct_mutex);
282
283 #ifdef __alpha__
284         /*
285          * Default the hose
286          */
287         if (!dev->hose) {
288                 struct pci_dev *pci_dev;
289                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
290                 if (pci_dev) {
291                         dev->hose = pci_dev->sysdata;
292                         pci_dev_put(pci_dev);
293                 }
294                 if (!dev->hose) {
295                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
296                         if (b)
297                                 dev->hose = b->sysdata;
298                 }
299         }
300 #endif
301
302         return 0;
303       out_free:
304         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
305         filp->private_data = NULL;
306         return ret;
307 }
308
309 /** No-op. */
310 int drm_fasync(int fd, struct file *filp, int on)
311 {
312         drm_file_t *priv = filp->private_data;
313         drm_device_t *dev = priv->head->dev;
314         int retcode;
315
316         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
317                   (long)old_encode_dev(priv->head->device));
318         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
319         if (retcode < 0)
320                 return retcode;
321         return 0;
322 }
323 EXPORT_SYMBOL(drm_fasync);
324
325 /**
326  * Release file.
327  *
328  * \param inode device inode
329  * \param filp file pointer.
330  * \return zero on success or a negative number on failure.
331  *
332  * If the hardware lock is held then free it, and take it again for the kernel
333  * context since it's necessary to reclaim buffers. Unlink the file private
334  * data from its list and free it. Decreases the open count and if it reaches
335  * zero calls drm_lastclose().
336  */
337 int drm_release(struct inode *inode, struct file *filp)
338 {
339         drm_file_t *priv = filp->private_data;
340         drm_device_t *dev;
341         int retcode = 0;
342
343         lock_kernel();
344         dev = priv->head->dev;
345
346         DRM_DEBUG("open_count = %d\n", dev->open_count);
347
348         if (dev->driver->preclose)
349                 dev->driver->preclose(dev, filp);
350
351         /* ========================================================
352          * Begin inline drm_release
353          */
354
355         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
356                   current->pid, (long)old_encode_dev(priv->head->device),
357                   dev->open_count);
358
359         if (dev->driver->reclaim_buffers_locked && dev->lock.hw_lock) {
360                 if (drm_i_have_hw_lock(filp)) {
361                         dev->driver->reclaim_buffers_locked(dev, filp);
362                 } else {
363                         unsigned long _end=jiffies + 3*DRM_HZ;
364                         int locked = 0;
365
366                         drm_idlelock_take(&dev->lock);
367
368                         /*
369                          * Wait for a while.
370                          */
371
372                         do{
373                                 spin_lock(&dev->lock.spinlock);
374                                 locked = dev->lock.idle_has_lock;
375                                 spin_unlock(&dev->lock.spinlock);
376                                 if (locked)
377                                         break;
378                                 schedule();
379                         } while (!time_after_eq(jiffies, _end));
380
381                         if (!locked) {
382                                 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
383                                           "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
384                                           "\tI will go on reclaiming the buffers anyway.\n");
385                         }
386
387                         dev->driver->reclaim_buffers_locked(dev, filp);
388                         drm_idlelock_release(&dev->lock);
389                 }
390         }
391
392         if (dev->driver->reclaim_buffers_idlelocked && dev->lock.hw_lock) {
393
394                 drm_idlelock_take(&dev->lock);
395                 dev->driver->reclaim_buffers_idlelocked(dev, filp);
396                 drm_idlelock_release(&dev->lock);
397
398         }
399
400         if (drm_i_have_hw_lock(filp)) {
401                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
402                           filp, _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
403
404                 drm_lock_free(&dev->lock,
405                               _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
406         }
407
408
409         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
410             !dev->driver->reclaim_buffers_locked) {
411                 dev->driver->reclaim_buffers(dev, filp);
412         }
413
414         drm_fasync(-1, filp, 0);
415
416         mutex_lock(&dev->ctxlist_mutex);
417         if (dev->ctxlist && (!list_empty(&dev->ctxlist->head))) {
418                 drm_ctx_list_t *pos, *n;
419
420                 list_for_each_entry_safe(pos, n, &dev->ctxlist->head, head) {
421                         if (pos->tag == priv &&
422                             pos->handle != DRM_KERNEL_CONTEXT) {
423                                 if (dev->driver->context_dtor)
424                                         dev->driver->context_dtor(dev,
425                                                                   pos->handle);
426
427                                 drm_ctxbitmap_free(dev, pos->handle);
428
429                                 list_del(&pos->head);
430                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
431                                 --dev->ctx_count;
432                         }
433                 }
434         }
435         mutex_unlock(&dev->ctxlist_mutex);
436
437         mutex_lock(&dev->struct_mutex);
438         if (priv->remove_auth_on_close == 1) {
439                 drm_file_t *temp = dev->file_first;
440                 while (temp) {
441                         temp->authenticated = 0;
442                         temp = temp->next;
443                 }
444         }
445         if (priv->prev) {
446                 priv->prev->next = priv->next;
447         } else {
448                 dev->file_first = priv->next;
449         }
450         if (priv->next) {
451                 priv->next->prev = priv->prev;
452         } else {
453                 dev->file_last = priv->prev;
454         }
455         mutex_unlock(&dev->struct_mutex);
456
457         if (dev->driver->postclose)
458                 dev->driver->postclose(dev, priv);
459         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
460
461         /* ========================================================
462          * End inline drm_release
463          */
464
465         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
466         spin_lock(&dev->count_lock);
467         if (!--dev->open_count) {
468                 if (atomic_read(&dev->ioctl_count) || dev->blocked) {
469                         DRM_ERROR("Device busy: %d %d\n",
470                                   atomic_read(&dev->ioctl_count), dev->blocked);
471                         spin_unlock(&dev->count_lock);
472                         unlock_kernel();
473                         return -EBUSY;
474                 }
475                 spin_unlock(&dev->count_lock);
476                 unlock_kernel();
477                 return drm_lastclose(dev);
478         }
479         spin_unlock(&dev->count_lock);
480
481         unlock_kernel();
482
483         return retcode;
484 }
485 EXPORT_SYMBOL(drm_release);
486
487 /** No-op. */
488 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
489 {
490         return 0;
491 }
492 EXPORT_SYMBOL(drm_poll);