drivers/char/drm/drm_fops.c

   1 /**
   2  * \file drm_fops.h
   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
  40 static int drm_open_helper(struct inode *inode, struct file *filp, drm_device_t *dev);
  41
  42 static int drm_setup( drm_device_t *dev )
  43 {
  44         int i;
  45         int ret;
  46
  47         if (dev->driver->presetup)
  48         {
  49                 ret=dev->driver->presetup(dev);
  50                 if (ret!=0)
  51                         return ret;
  52         }
  53
  54         atomic_set( &dev->ioctl_count, 0 );
  55         atomic_set( &dev->vma_count, 0 );
  56         dev->buf_use = 0;
  57         atomic_set( &dev->buf_alloc, 0 );
  58
  59         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
  60         {
  61                 i = drm_dma_setup( dev );
  62                 if ( i < 0 )
  63                         return i;
  64         }
  65
  66         for ( i = 0 ; i < DRM_ARRAY_SIZE(dev->counts) ; i++ )
  67                 atomic_set( &dev->counts[i], 0 );
  68
  69         for ( i = 0 ; i < DRM_HASH_SIZE ; i++ ) {
  70                 dev->magiclist[i].head = NULL;
  71                 dev->magiclist[i].tail = NULL;
  72         }
  73
  74         dev->ctxlist = drm_alloc(sizeof(*dev->ctxlist),
  75                                   DRM_MEM_CTXLIST);
  76         if(dev->ctxlist == NULL) return -ENOMEM;
  77         memset(dev->ctxlist, 0, sizeof(*dev->ctxlist));
  78         INIT_LIST_HEAD(&dev->ctxlist->head);
  79
  80         dev->vmalist = NULL;
  81         dev->sigdata.lock = dev->lock.hw_lock = NULL;
  82         init_waitqueue_head( &dev->lock.lock_queue );
  83         dev->queue_count = 0;
  84         dev->queue_reserved = 0;
  85         dev->queue_slots = 0;
  86         dev->queuelist = NULL;
  87         dev->irq_enabled = 0;
  88         dev->context_flag = 0;
  89         dev->interrupt_flag = 0;
  90         dev->dma_flag = 0;
  91         dev->last_context = 0;
  92         dev->last_switch = 0;
  93         dev->last_checked = 0;
  94         init_waitqueue_head( &dev->context_wait );
  95         dev->if_version = 0;
  96
  97         dev->ctx_start = 0;
  98         dev->lck_start = 0;
  99
 100         dev->buf_rp = dev->buf;
 101         dev->buf_wp = dev->buf;
 102         dev->buf_end = dev->buf + DRM_BSZ;
 103         dev->buf_async = NULL;
 104         init_waitqueue_head( &dev->buf_readers );
 105         init_waitqueue_head( &dev->buf_writers );
 106
 107         DRM_DEBUG( "\n" );
 108
 109         /*
 110          * The kernel's context could be created here, but is now created
 111          * in drm_dma_enqueue.  This is more resource-efficient for
 112          * hardware that does not do DMA, but may mean that
 113          * drm_select_queue fails between the time the interrupt is
 114          * initialized and the time the queues are initialized.
 115          */
 116         if (dev->driver->postsetup)
 117                 dev->driver->postsetup(dev);
 118
 119         return 0;
 120 }
 121
 122 /**
 123  * Open file.
 124  *
 125  * \param inode device inode
 126  * \param filp file pointer.
 127  * \return zero on success or a negative number on failure.
 128  *
 129  * Searches the DRM device with the same minor number, calls open_helper(), and
 130  * increments the device open count. If the open count was previous at zero,
 131  * i.e., it's the first that the device is open, then calls setup().
 132  */
 133 int drm_open( struct inode *inode, struct file *filp )
 134 {
 135         drm_device_t *dev = NULL;
 136         int minor = iminor(inode);
 137         int retcode = 0;
 138
 139         if (!((minor >= 0) && (minor < drm_cards_limit)))
 140                 return -ENODEV;
 141
 142         if (!drm_heads[minor])
 143                 return -ENODEV;
 144
 145         if (!(dev = drm_heads[minor]->dev))
 146                 return -ENODEV;
 147
 148         retcode = drm_open_helper( inode, filp, dev );
 149         if ( !retcode ) {
 150                 atomic_inc( &dev->counts[_DRM_STAT_OPENS] );
 151                 spin_lock( &dev->count_lock );
 152                 if ( !dev->open_count++ ) {
 153                         spin_unlock( &dev->count_lock );
 154                         return drm_setup( dev );
 155                 }
 156                 spin_unlock( &dev->count_lock );
 157         }
 158
 159         return retcode;
 160 }
 161 EXPORT_SYMBOL(drm_open);
 162
 163 /**
 164  * Release file.
 165  *
 166  * \param inode device inode
 167  * \param filp file pointer.
 168  * \return zero on success or a negative number on failure.
 169  *
 170  * If the hardware lock is held then free it, and take it again for the kernel
 171  * context since it's necessary to reclaim buffers. Unlink the file private
 172  * data from its list and free it. Decreases the open count and if it reaches
 173  * zero calls takedown().
 174  */
 175 int drm_release( struct inode *inode, struct file *filp )
 176 {
 177         drm_file_t *priv = filp->private_data;
 178         drm_device_t *dev;
 179         int retcode = 0;
 180
 181         lock_kernel();
 182         dev = priv->head->dev;
 183
 184         DRM_DEBUG( "open_count = %d\n", dev->open_count );
 185
 186         if (dev->driver->prerelease)
 187                 dev->driver->prerelease(dev, filp);
 188
 189         /* ========================================================
 190          * Begin inline drm_release
 191          */
 192
 193         DRM_DEBUG( "pid = %d, device = 0x%lx, open_count = %d\n",
 194                    current->pid, (long)old_encode_dev(priv->head->device), dev->open_count );
 195
 196         if ( priv->lock_count && dev->lock.hw_lock &&
 197              _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) &&
 198              dev->lock.filp == filp ) {
 199                 DRM_DEBUG( "File %p released, freeing lock for context %d\n",
 200                         filp,
 201                         _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
 202
 203                 if (dev->driver->release)
 204                         dev->driver->release(dev, filp);
 205
 206                 drm_lock_free( dev, &dev->lock.hw_lock->lock,
 207                                 _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
 208
 209                                 /* FIXME: may require heavy-handed reset of
 210                                    hardware at this point, possibly
 211                                    processed via a callback to the X
 212                                    server. */
 213         }
 214         else if ( dev->driver->release && priv->lock_count && dev->lock.hw_lock ) {
 215                 /* The lock is required to reclaim buffers */
 216                 DECLARE_WAITQUEUE( entry, current );
 217
 218                 add_wait_queue( &dev->lock.lock_queue, &entry );
 219                 for (;;) {
 220                         __set_current_state(TASK_INTERRUPTIBLE);
 221                         if ( !dev->lock.hw_lock ) {
 222                                 /* Device has been unregistered */
 223                                 retcode = -EINTR;
 224                                 break;
 225                         }
 226                         if ( drm_lock_take( &dev->lock.hw_lock->lock,
 227                                              DRM_KERNEL_CONTEXT ) ) {
 228                                 dev->lock.filp      = filp;
 229                                 dev->lock.lock_time = jiffies;
 230                                 atomic_inc( &dev->counts[_DRM_STAT_LOCKS] );
 231                                 break;  /* Got lock */
 232                         }
 233                                 /* Contention */
 234                         schedule();
 235                         if ( signal_pending( current ) ) {
 236                                 retcode = -ERESTARTSYS;
 237                                 break;
 238                         }
 239                 }
 240                 __set_current_state(TASK_RUNNING);
 241                 remove_wait_queue( &dev->lock.lock_queue, &entry );
 242                 if( !retcode ) {
 243                         if (dev->driver->release)
 244                                 dev->driver->release(dev, filp);
 245                         drm_lock_free( dev, &dev->lock.hw_lock->lock,
 246                                         DRM_KERNEL_CONTEXT );
 247                 }
 248         }
 249
 250         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && !dev->driver->release)
 251         {
 252                 dev->driver->reclaim_buffers(dev, filp);
 253         }
 254
 255         drm_fasync( -1, filp, 0 );
 256
 257         down( &dev->ctxlist_sem );
 258         if ( dev->ctxlist && (!list_empty(&dev->ctxlist->head))) {
 259                 drm_ctx_list_t *pos, *n;
 260
 261                 list_for_each_entry_safe( pos, n, &dev->ctxlist->head, head ) {
 262                         if ( pos->tag == priv &&
 263                              pos->handle != DRM_KERNEL_CONTEXT ) {
 264                                 if (dev->driver->context_dtor)
 265                                         dev->driver->context_dtor(dev, pos->handle);
 266
 267                                 drm_ctxbitmap_free( dev, pos->handle );
 268
 269                                 list_del( &pos->head );
 270                                 drm_free( pos, sizeof(*pos), DRM_MEM_CTXLIST );
 271                                 --dev->ctx_count;
 272                         }
 273                 }
 274         }
 275         up( &dev->ctxlist_sem );
 276
 277         down( &dev->struct_sem );
 278         if ( priv->remove_auth_on_close == 1 ) {
 279                 drm_file_t *temp = dev->file_first;
 280                 while ( temp ) {
 281                         temp->authenticated = 0;
 282                         temp = temp->next;
 283                 }
 284         }
 285         if ( priv->prev ) {
 286                 priv->prev->next = priv->next;
 287         } else {
 288                 dev->file_first  = priv->next;
 289         }
 290         if ( priv->next ) {
 291                 priv->next->prev = priv->prev;
 292         } else {
 293                 dev->file_last   = priv->prev;
 294         }
 295         up( &dev->struct_sem );
 296
 297         if (dev->driver->free_filp_priv)
 298                 dev->driver->free_filp_priv(dev, priv);
 299
 300         drm_free( priv, sizeof(*priv), DRM_MEM_FILES );
 301
 302         /* ========================================================
 303          * End inline drm_release
 304          */
 305
 306         atomic_inc( &dev->counts[_DRM_STAT_CLOSES] );
 307         spin_lock( &dev->count_lock );
 308         if ( !--dev->open_count ) {
 309                 if ( atomic_read( &dev->ioctl_count ) || dev->blocked ) {
 310                         DRM_ERROR( "Device busy: %d %d\n",
 311                                    atomic_read( &dev->ioctl_count ),
 312                                    dev->blocked );
 313                         spin_unlock( &dev->count_lock );
 314                         unlock_kernel();
 315                         return -EBUSY;
 316                 }
 317                 spin_unlock( &dev->count_lock );
 318                 unlock_kernel();
 319                 return drm_takedown( dev );
 320         }
 321         spin_unlock( &dev->count_lock );
 322
 323         unlock_kernel();
 324
 325         return retcode;
 326 }
 327 EXPORT_SYMBOL(drm_release);
 328
 329 /**
 330  * Called whenever a process opens /dev/drm.
 331  *
 332  * \param inode device inode.
 333  * \param filp file pointer.
 334  * \param dev device.
 335  * \return zero on success or a negative number on failure.
 336  *
 337  * Creates and initializes a drm_file structure for the file private data in \p
 338  * filp and add it into the double linked list in \p dev.
 339  */
 340 static int drm_open_helper(struct inode *inode, struct file *filp, drm_device_t *dev)
 341 {
 342         int          minor = iminor(inode);
 343         drm_file_t   *priv;
 344         int ret;
 345
 346         if (filp->f_flags & O_EXCL)   return -EBUSY; /* No exclusive opens */
 347         if (!drm_cpu_valid())        return -EINVAL;
 348
 349         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
 350
 351         priv                = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 352         if(!priv) return -ENOMEM;
 353
 354         memset(priv, 0, sizeof(*priv));
 355         filp->private_data  = priv;
 356         priv->uid           = current->euid;
 357         priv->pid           = current->pid;
 358         priv->minor         = minor;
 359         priv->head          = drm_heads[minor];
 360         priv->ioctl_count   = 0;
 361         priv->authenticated = capable(CAP_SYS_ADMIN);
 362         priv->lock_count    = 0;
 363
 364         if (dev->driver->open_helper) {
 365                 ret=dev->driver->open_helper(dev, priv);
 366                 if (ret < 0)
 367                         goto out_free;
 368         }
 369
 370         down(&dev->struct_sem);
 371         if (!dev->file_last) {
 372                 priv->next      = NULL;
 373                 priv->prev      = NULL;
 374                 dev->file_first = priv;
 375                 dev->file_last  = priv;
 376         } else {
 377                 priv->next           = NULL;
 378                 priv->prev           = dev->file_last;
 379                 dev->file_last->next = priv;
 380                 dev->file_last       = priv;
 381         }
 382         up(&dev->struct_sem);
 383
 384 #ifdef __alpha__
 385         /*
 386          * Default the hose
 387          */
 388         if (!dev->hose) {
 389                 struct pci_dev *pci_dev;
 390                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 391                 if (pci_dev) {
 392                         dev->hose = pci_dev->sysdata;
 393                         pci_dev_put(pci_dev);
 394                 }
 395                 if (!dev->hose) {
 396                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 397                         if (b) dev->hose = b->sysdata;
 398                 }
 399         }
 400 #endif
 401
 402         return 0;
 403 out_free:
 404         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 405         filp->private_data=NULL;
 406         return ret;
 407 }
 408
 409 /** No-op. */
 410 int drm_flush(struct file *filp)
 411 {
 412         drm_file_t    *priv   = filp->private_data;
 413         drm_device_t  *dev    = priv->head->dev;
 414
 415         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 416                   current->pid, (long)old_encode_dev(priv->head->device), dev->open_count);
 417         return 0;
 418 }
 419 EXPORT_SYMBOL(drm_flush);
 420
 421 /** No-op. */
 422 int drm_fasync(int fd, struct file *filp, int on)
 423 {
 424         drm_file_t    *priv   = filp->private_data;
 425         drm_device_t  *dev    = priv->head->dev;
 426         int           retcode;
 427
 428         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, (long)old_encode_dev(priv->head->device));
 429         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 430         if (retcode < 0) return retcode;
 431         return 0;
 432 }
 433 EXPORT_SYMBOL(drm_fasync);
 434
 435 /** No-op. */
 436 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 437 {
 438         return 0;
 439 }
 440 EXPORT_SYMBOL(drm_poll);
 441