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