e1000e: don't poke PHY registers to retreive link status
[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                            struct drm_device * dev);
43
44 static int drm_setup(struct drm_device * 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->sigdata.lock = NULL;
83         init_waitqueue_head(&dev->lock.lock_queue);
84         dev->queue_count = 0;
85         dev->queue_reserved = 0;
86         dev->queue_slots = 0;
87         dev->queuelist = NULL;
88         dev->irq_enabled = 0;
89         dev->context_flag = 0;
90         dev->interrupt_flag = 0;
91         dev->dma_flag = 0;
92         dev->last_context = 0;
93         dev->last_switch = 0;
94         dev->last_checked = 0;
95         init_waitqueue_head(&dev->context_wait);
96         dev->if_version = 0;
97
98         dev->ctx_start = 0;
99         dev->lck_start = 0;
100
101         dev->buf_async = NULL;
102         init_waitqueue_head(&dev->buf_readers);
103         init_waitqueue_head(&dev->buf_writers);
104
105         DRM_DEBUG("\n");
106
107         /*
108          * The kernel's context could be created here, but is now created
109          * in drm_dma_enqueue.  This is more resource-efficient for
110          * hardware that does not do DMA, but may mean that
111          * drm_select_queue fails between the time the interrupt is
112          * initialized and the time the queues are initialized.
113          */
114
115         return 0;
116 }
117
118 /**
119  * Open file.
120  *
121  * \param inode device inode
122  * \param filp file pointer.
123  * \return zero on success or a negative number on failure.
124  *
125  * Searches the DRM device with the same minor number, calls open_helper(), and
126  * increments the device open count. If the open count was previous at zero,
127  * i.e., it's the first that the device is open, then calls setup().
128  */
129 int drm_open(struct inode *inode, struct file *filp)
130 {
131         struct drm_device *dev = NULL;
132         int minor = iminor(inode);
133         int retcode = 0;
134
135         if (!((minor >= 0) && (minor < drm_cards_limit)))
136                 return -ENODEV;
137
138         if (!drm_heads[minor])
139                 return -ENODEV;
140
141         if (!(dev = drm_heads[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         int minor = iminor(inode);
172         int err = -ENODEV;
173         const struct file_operations *old_fops;
174
175         DRM_DEBUG("\n");
176
177         if (!((minor >= 0) && (minor < drm_cards_limit)))
178                 return -ENODEV;
179
180         if (!drm_heads[minor])
181                 return -ENODEV;
182
183         if (!(dev = drm_heads[minor]->dev))
184                 return -ENODEV;
185
186         old_fops = filp->f_op;
187         filp->f_op = fops_get(&dev->driver->fops);
188         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
189                 fops_put(filp->f_op);
190                 filp->f_op = fops_get(old_fops);
191         }
192         fops_put(old_fops);
193
194         return err;
195 }
196
197 /**
198  * Check whether DRI will run on this CPU.
199  *
200  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
201  */
202 static int drm_cpu_valid(void)
203 {
204 #if defined(__i386__)
205         if (boot_cpu_data.x86 == 3)
206                 return 0;       /* No cmpxchg on a 386 */
207 #endif
208 #if defined(__sparc__) && !defined(__sparc_v9__)
209         return 0;               /* No cmpxchg before v9 sparc. */
210 #endif
211         return 1;
212 }
213
214 /**
215  * Called whenever a process opens /dev/drm.
216  *
217  * \param inode device inode.
218  * \param filp file pointer.
219  * \param dev device.
220  * \return zero on success or a negative number on failure.
221  *
222  * Creates and initializes a drm_file structure for the file private data in \p
223  * filp and add it into the double linked list in \p dev.
224  */
225 static int drm_open_helper(struct inode *inode, struct file *filp,
226                            struct drm_device * dev)
227 {
228         int minor = iminor(inode);
229         struct drm_file *priv;
230         int ret;
231
232         if (filp->f_flags & O_EXCL)
233                 return -EBUSY;  /* No exclusive opens */
234         if (!drm_cpu_valid())
235                 return -EINVAL;
236
237         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
238
239         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
240         if (!priv)
241                 return -ENOMEM;
242
243         memset(priv, 0, sizeof(*priv));
244         filp->private_data = priv;
245         priv->filp = filp;
246         priv->uid = current->euid;
247         priv->pid = current->pid;
248         priv->minor = minor;
249         priv->head = drm_heads[minor];
250         priv->ioctl_count = 0;
251         /* for compatibility root is always authenticated */
252         priv->authenticated = capable(CAP_SYS_ADMIN);
253         priv->lock_count = 0;
254
255         INIT_LIST_HEAD(&priv->lhead);
256
257         if (dev->driver->open) {
258                 ret = dev->driver->open(dev, priv);
259                 if (ret < 0)
260                         goto out_free;
261         }
262
263         mutex_lock(&dev->struct_mutex);
264         if (list_empty(&dev->filelist))
265                 priv->master = 1;
266
267         list_add(&priv->lhead, &dev->filelist);
268         mutex_unlock(&dev->struct_mutex);
269
270 #ifdef __alpha__
271         /*
272          * Default the hose
273          */
274         if (!dev->hose) {
275                 struct pci_dev *pci_dev;
276                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
277                 if (pci_dev) {
278                         dev->hose = pci_dev->sysdata;
279                         pci_dev_put(pci_dev);
280                 }
281                 if (!dev->hose) {
282                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
283                         if (b)
284                                 dev->hose = b->sysdata;
285                 }
286         }
287 #endif
288
289         return 0;
290       out_free:
291         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
292         filp->private_data = NULL;
293         return ret;
294 }
295
296 /** No-op. */
297 int drm_fasync(int fd, struct file *filp, int on)
298 {
299         struct drm_file *priv = filp->private_data;
300         struct drm_device *dev = priv->head->dev;
301         int retcode;
302
303         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
304                   (long)old_encode_dev(priv->head->device));
305         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
306         if (retcode < 0)
307                 return retcode;
308         return 0;
309 }
310 EXPORT_SYMBOL(drm_fasync);
311
312 /**
313  * Release file.
314  *
315  * \param inode device inode
316  * \param file_priv DRM file private.
317  * \return zero on success or a negative number on failure.
318  *
319  * If the hardware lock is held then free it, and take it again for the kernel
320  * context since it's necessary to reclaim buffers. Unlink the file private
321  * data from its list and free it. Decreases the open count and if it reaches
322  * zero calls drm_lastclose().
323  */
324 int drm_release(struct inode *inode, struct file *filp)
325 {
326         struct drm_file *file_priv = filp->private_data;
327         struct drm_device *dev = file_priv->head->dev;
328         int retcode = 0;
329
330         lock_kernel();
331
332         DRM_DEBUG("open_count = %d\n", dev->open_count);
333
334         if (dev->driver->preclose)
335                 dev->driver->preclose(dev, file_priv);
336
337         /* ========================================================
338          * Begin inline drm_release
339          */
340
341         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
342                   current->pid, (long)old_encode_dev(file_priv->head->device),
343                   dev->open_count);
344
345         if (dev->driver->reclaim_buffers_locked && dev->lock.hw_lock) {
346                 if (drm_i_have_hw_lock(dev, file_priv)) {
347                         dev->driver->reclaim_buffers_locked(dev, file_priv);
348                 } else {
349                         unsigned long _end=jiffies + 3*DRM_HZ;
350                         int locked = 0;
351
352                         drm_idlelock_take(&dev->lock);
353
354                         /*
355                          * Wait for a while.
356                          */
357
358                         do{
359                                 spin_lock(&dev->lock.spinlock);
360                                 locked = dev->lock.idle_has_lock;
361                                 spin_unlock(&dev->lock.spinlock);
362                                 if (locked)
363                                         break;
364                                 schedule();
365                         } while (!time_after_eq(jiffies, _end));
366
367                         if (!locked) {
368                                 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
369                                           "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
370                                           "\tI will go on reclaiming the buffers anyway.\n");
371                         }
372
373                         dev->driver->reclaim_buffers_locked(dev, file_priv);
374                         drm_idlelock_release(&dev->lock);
375                 }
376         }
377
378         if (dev->driver->reclaim_buffers_idlelocked && dev->lock.hw_lock) {
379
380                 drm_idlelock_take(&dev->lock);
381                 dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
382                 drm_idlelock_release(&dev->lock);
383
384         }
385
386         if (drm_i_have_hw_lock(dev, file_priv)) {
387                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
388                           filp, _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
389
390                 drm_lock_free(&dev->lock,
391                               _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
392         }
393
394
395         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
396             !dev->driver->reclaim_buffers_locked) {
397                 dev->driver->reclaim_buffers(dev, file_priv);
398         }
399
400         drm_fasync(-1, filp, 0);
401
402         mutex_lock(&dev->ctxlist_mutex);
403         if (!list_empty(&dev->ctxlist)) {
404                 struct drm_ctx_list *pos, *n;
405
406                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
407                         if (pos->tag == file_priv &&
408                             pos->handle != DRM_KERNEL_CONTEXT) {
409                                 if (dev->driver->context_dtor)
410                                         dev->driver->context_dtor(dev,
411                                                                   pos->handle);
412
413                                 drm_ctxbitmap_free(dev, pos->handle);
414
415                                 list_del(&pos->head);
416                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
417                                 --dev->ctx_count;
418                         }
419                 }
420         }
421         mutex_unlock(&dev->ctxlist_mutex);
422
423         mutex_lock(&dev->struct_mutex);
424         if (file_priv->remove_auth_on_close == 1) {
425                 struct drm_file *temp;
426
427                 list_for_each_entry(temp, &dev->filelist, lhead)
428                         temp->authenticated = 0;
429         }
430         list_del(&file_priv->lhead);
431         mutex_unlock(&dev->struct_mutex);
432
433         if (dev->driver->postclose)
434                 dev->driver->postclose(dev, file_priv);
435         drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES);
436
437         /* ========================================================
438          * End inline drm_release
439          */
440
441         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
442         spin_lock(&dev->count_lock);
443         if (!--dev->open_count) {
444                 if (atomic_read(&dev->ioctl_count) || dev->blocked) {
445                         DRM_ERROR("Device busy: %d %d\n",
446                                   atomic_read(&dev->ioctl_count), dev->blocked);
447                         spin_unlock(&dev->count_lock);
448                         unlock_kernel();
449                         return -EBUSY;
450                 }
451                 spin_unlock(&dev->count_lock);
452                 unlock_kernel();
453                 return drm_lastclose(dev);
454         }
455         spin_unlock(&dev->count_lock);
456
457         unlock_kernel();
458
459         return retcode;
460 }
461 EXPORT_SYMBOL(drm_release);
462
463 /** No-op. */
464 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
465 {
466         return 0;
467 }
468 EXPORT_SYMBOL(drm_poll);