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->maplist = drm_alloc(sizeof(*dev->maplist),
  75                                   DRM_MEM_MAPS);
  76         if(dev->maplist == NULL) return -ENOMEM;
  77         memset(dev->maplist, 0, sizeof(*dev->maplist));
  78         INIT_LIST_HEAD(&dev->maplist->head);
  79
  80         dev->ctxlist = drm_alloc(sizeof(*dev->ctxlist),
  81                                   DRM_MEM_CTXLIST);
  82         if(dev->ctxlist == NULL) return -ENOMEM;
  83         memset(dev->ctxlist, 0, sizeof(*dev->ctxlist));
  84         INIT_LIST_HEAD(&dev->ctxlist->head);
  85
  86         dev->vmalist = NULL;
  87         dev->sigdata.lock = dev->lock.hw_lock = NULL;
  88         init_waitqueue_head( &dev->lock.lock_queue );
  89         dev->queue_count = 0;
  90         dev->queue_reserved = 0;
  91         dev->queue_slots = 0;
  92         dev->queuelist = NULL;
  93         dev->irq_enabled = 0;
  94         dev->context_flag = 0;
  95         dev->interrupt_flag = 0;
  96         dev->dma_flag = 0;
  97         dev->last_context = 0;
  98         dev->last_switch = 0;
  99         dev->last_checked = 0;
 100         init_waitqueue_head( &dev->context_wait );
 101         dev->if_version = 0;
 102
 103         dev->ctx_start = 0;
 104         dev->lck_start = 0;
 105
 106         dev->buf_rp = dev->buf;
 107         dev->buf_wp = dev->buf;
 108         dev->buf_end = dev->buf + DRM_BSZ;
 109         dev->buf_async = NULL;
 110         init_waitqueue_head( &dev->buf_readers );
 111         init_waitqueue_head( &dev->buf_writers );
 112
 113         DRM_DEBUG( "\n" );
 114
 115         /*
 116          * The kernel's context could be created here, but is now created
 117          * in drm_dma_enqueue.  This is more resource-efficient for
 118          * hardware that does not do DMA, but may mean that
 119          * drm_select_queue fails between the time the interrupt is
 120          * initialized and the time the queues are initialized.
 121          */
 122         if (dev->driver->postsetup)
 123                 dev->driver->postsetup(dev);
 124
 125         return 0;
 126 }
 127
 128 /**
 129  * Open file.
 130  *
 131  * \param inode device inode
 132  * \param filp file pointer.
 133  * \return zero on success or a negative number on failure.
 134  *
 135  * Searches the DRM device with the same minor number, calls open_helper(), and
 136  * increments the device open count. If the open count was previous at zero,
 137  * i.e., it's the first that the device is open, then calls setup().
 138  */
 139 int drm_open( struct inode *inode, struct file *filp )
 140 {
 141         drm_device_t *dev = NULL;
 142         int minor = iminor(inode);
 143         int retcode = 0;
 144
 145         if (!((minor >= 0) && (minor < drm_cards_limit)))
 146                 return -ENODEV;
 147
 148         if (!drm_heads[minor])
 149                 return -ENODEV;
 150
 151         if (!(dev = drm_heads[minor]->dev))
 152                 return -ENODEV;
 153
 154         retcode = drm_open_helper( inode, filp, dev );
 155         if ( !retcode ) {
 156                 atomic_inc( &dev->counts[_DRM_STAT_OPENS] );
 157                 spin_lock( &dev->count_lock );
 158                 if ( !dev->open_count++ ) {
 159                         spin_unlock( &dev->count_lock );
 160                         return drm_setup( dev );
 161                 }
 162                 spin_unlock( &dev->count_lock );
 163         }
 164
 165         return retcode;
 166 }
 167 EXPORT_SYMBOL(drm_open);
 168
 169 /**
 170  * Release file.
 171  *
 172  * \param inode device inode
 173  * \param filp file pointer.
 174  * \return zero on success or a negative number on failure.
 175  *
 176  * If the hardware lock is held then free it, and take it again for the kernel
 177  * context since it's necessary to reclaim buffers. Unlink the file private
 178  * data from its list and free it. Decreases the open count and if it reaches
 179  * zero calls takedown().
 180  */
 181 int drm_release( struct inode *inode, struct file *filp )
 182 {
 183         drm_file_t *priv = filp->private_data;
 184         drm_device_t *dev;
 185         int retcode = 0;
 186
 187         lock_kernel();
 188         dev = priv->head->dev;
 189
 190         DRM_DEBUG( "open_count = %d\n", dev->open_count );
 191
 192         if (dev->driver->prerelease)
 193                 dev->driver->prerelease(dev, filp);
 194
 195         /* ========================================================
 196          * Begin inline drm_release
 197          */
 198
 199         DRM_DEBUG( "pid = %d, device = 0x%lx, open_count = %d\n",
 200                    current->pid, (long)old_encode_dev(priv->head->device), dev->open_count );
 201
 202         if ( priv->lock_count && dev->lock.hw_lock &&
 203              _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) &&
 204              dev->lock.filp == filp ) {
 205                 DRM_DEBUG( "File %p released, freeing lock for context %d\n",
 206                         filp,
 207                         _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
 208
 209                 if (dev->driver->release)
 210                         dev->driver->release(dev, filp);
 211
 212                 drm_lock_free( dev, &dev->lock.hw_lock->lock,
 213                                 _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
 214
 215                                 /* FIXME: may require heavy-handed reset of
 216                                    hardware at this point, possibly
 217                                    processed via a callback to the X
 218                                    server. */
 219         }
 220         else if ( dev->driver->release && priv->lock_count && dev->lock.hw_lock ) {
 221                 /* The lock is required to reclaim buffers */
 222                 DECLARE_WAITQUEUE( entry, current );
 223
 224                 add_wait_queue( &dev->lock.lock_queue, &entry );
 225                 for (;;) {
 226                         __set_current_state(TASK_INTERRUPTIBLE);
 227                         if ( !dev->lock.hw_lock ) {
 228                                 /* Device has been unregistered */
 229                                 retcode = -EINTR;
 230                                 break;
 231                         }
 232                         if ( drm_lock_take( &dev->lock.hw_lock->lock,
 233                                              DRM_KERNEL_CONTEXT ) ) {
 234                                 dev->lock.filp      = filp;
 235                                 dev->lock.lock_time = jiffies;
 236                                 atomic_inc( &dev->counts[_DRM_STAT_LOCKS] );
 237                                 break;  /* Got lock */
 238                         }
 239                                 /* Contention */
 240                         schedule();
 241                         if ( signal_pending( current ) ) {
 242                                 retcode = -ERESTARTSYS;
 243                                 break;
 244                         }
 245                 }
 246                 __set_current_state(TASK_RUNNING);
 247                 remove_wait_queue( &dev->lock.lock_queue, &entry );
 248                 if( !retcode ) {
 249                         if (dev->driver->release)
 250                                 dev->driver->release(dev, filp);
 251                         drm_lock_free( dev, &dev->lock.hw_lock->lock,
 252                                         DRM_KERNEL_CONTEXT );
 253                 }
 254         }
 255
 256         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && !dev->driver->release)
 257         {
 258                 dev->driver->reclaim_buffers(dev, filp);
 259         }
 260
 261         drm_fasync( -1, filp, 0 );
 262
 263         down( &dev->ctxlist_sem );
 264         if ( dev->ctxlist && (!list_empty(&dev->ctxlist->head))) {
 265                 drm_ctx_list_t *pos, *n;
 266
 267                 list_for_each_entry_safe( pos, n, &dev->ctxlist->head, head ) {
 268                         if ( pos->tag == priv &&
 269                              pos->handle != DRM_KERNEL_CONTEXT ) {
 270                                 if (dev->driver->context_dtor)
 271                                         dev->driver->context_dtor(dev, pos->handle);
 272
 273                                 drm_ctxbitmap_free( dev, pos->handle );
 274
 275                                 list_del( &pos->head );
 276                                 drm_free( pos, sizeof(*pos), DRM_MEM_CTXLIST );
 277                                 --dev->ctx_count;
 278                         }
 279                 }
 280         }
 281         up( &dev->ctxlist_sem );
 282
 283         down( &dev->struct_sem );
 284         if ( priv->remove_auth_on_close == 1 ) {
 285                 drm_file_t *temp = dev->file_first;
 286                 while ( temp ) {
 287                         temp->authenticated = 0;
 288                         temp = temp->next;
 289                 }
 290         }
 291         if ( priv->prev ) {
 292                 priv->prev->next = priv->next;
 293         } else {
 294                 dev->file_first  = priv->next;
 295         }
 296         if ( priv->next ) {
 297                 priv->next->prev = priv->prev;
 298         } else {
 299                 dev->file_last   = priv->prev;
 300         }
 301         up( &dev->struct_sem );
 302
 303         if (dev->driver->free_filp_priv)
 304                 dev->driver->free_filp_priv(dev, priv);
 305
 306         drm_free( priv, sizeof(*priv), DRM_MEM_FILES );
 307
 308         /* ========================================================
 309          * End inline drm_release
 310          */
 311
 312         atomic_inc( &dev->counts[_DRM_STAT_CLOSES] );
 313         spin_lock( &dev->count_lock );
 314         if ( !--dev->open_count ) {
 315                 if ( atomic_read( &dev->ioctl_count ) || dev->blocked ) {
 316                         DRM_ERROR( "Device busy: %d %d\n",
 317                                    atomic_read( &dev->ioctl_count ),
 318                                    dev->blocked );
 319                         spin_unlock( &dev->count_lock );
 320                         unlock_kernel();
 321                         return -EBUSY;
 322                 }
 323                 spin_unlock( &dev->count_lock );
 324                 unlock_kernel();
 325                 return drm_takedown( dev );
 326         }
 327         spin_unlock( &dev->count_lock );
 328
 329         unlock_kernel();
 330
 331         return retcode;
 332 }
 333 EXPORT_SYMBOL(drm_release);
 334
 335 /**
 336  * Called whenever a process opens /dev/drm.
 337  *
 338  * \param inode device inode.
 339  * \param filp file pointer.
 340  * \param dev device.
 341  * \return zero on success or a negative number on failure.
 342  *
 343  * Creates and initializes a drm_file structure for the file private data in \p
 344  * filp and add it into the double linked list in \p dev.
 345  */
 346 static int drm_open_helper(struct inode *inode, struct file *filp, drm_device_t *dev)
 347 {
 348         int          minor = iminor(inode);
 349         drm_file_t   *priv;
 350         int ret;
 351
 352         if (filp->f_flags & O_EXCL)   return -EBUSY; /* No exclusive opens */
 353         if (!drm_cpu_valid())        return -EINVAL;
 354
 355         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
 356
 357         priv                = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 358         if(!priv) return -ENOMEM;
 359
 360         memset(priv, 0, sizeof(*priv));
 361         filp->private_data  = priv;
 362         priv->uid           = current->euid;
 363         priv->pid           = current->pid;
 364         priv->minor         = minor;
 365         priv->head          = drm_heads[minor];
 366         priv->ioctl_count   = 0;
 367         priv->authenticated = capable(CAP_SYS_ADMIN);
 368         priv->lock_count    = 0;
 369
 370         if (dev->driver->open_helper) {
 371                 ret=dev->driver->open_helper(dev, priv);
 372                 if (ret < 0)
 373                         goto out_free;
 374         }
 375
 376         down(&dev->struct_sem);
 377         if (!dev->file_last) {
 378                 priv->next      = NULL;
 379                 priv->prev      = NULL;
 380                 dev->file_first = priv;
 381                 dev->file_last  = priv;
 382         } else {
 383                 priv->next           = NULL;
 384                 priv->prev           = dev->file_last;
 385                 dev->file_last->next = priv;
 386                 dev->file_last       = priv;
 387         }
 388         up(&dev->struct_sem);
 389
 390 #ifdef __alpha__
 391         /*
 392          * Default the hose
 393          */
 394         if (!dev->hose) {
 395                 struct pci_dev *pci_dev;
 396                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 397                 if (pci_dev) {
 398                         dev->hose = pci_dev->sysdata;
 399                         pci_dev_put(pci_dev);
 400                 }
 401                 if (!dev->hose) {
 402                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 403                         if (b) dev->hose = b->sysdata;
 404                 }
 405         }
 406 #endif
 407
 408         return 0;
 409 out_free:
 410         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 411         filp->private_data=NULL;
 412         return ret;
 413 }
 414
 415 /** No-op. */
 416 int drm_flush(struct file *filp)
 417 {
 418         drm_file_t    *priv   = filp->private_data;
 419         drm_device_t  *dev    = priv->head->dev;
 420
 421         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 422                   current->pid, (long)old_encode_dev(priv->head->device), dev->open_count);
 423         return 0;
 424 }
 425 EXPORT_SYMBOL(drm_flush);
 426
 427 /** No-op. */
 428 int drm_fasync(int fd, struct file *filp, int on)
 429 {
 430         drm_file_t    *priv   = filp->private_data;
 431         drm_device_t  *dev    = priv->head->dev;
 432         int           retcode;
 433
 434         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, (long)old_encode_dev(priv->head->device));
 435         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 436         if (retcode < 0) return retcode;
 437         return 0;
 438 }
 439 EXPORT_SYMBOL(drm_fasync);
 440
 441 /** No-op. */
 442 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 443 {
 444         return 0;
 445 }
 446 EXPORT_SYMBOL(drm_poll);
 447