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_setup( drm_device_t *dev )
  41 {
  42         int i;
  43         int ret;
  44
  45         if (dev->driver->presetup)
  46         {
  47                 ret=dev->driver->presetup(dev);
  48                 if (ret!=0)
  49                         return ret;
  50         }
  51
  52         atomic_set( &dev->ioctl_count, 0 );
  53         atomic_set( &dev->vma_count, 0 );
  54         dev->buf_use = 0;
  55         atomic_set( &dev->buf_alloc, 0 );
  56
  57         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
  58         {
  59                 i = drm_dma_setup( dev );
  60                 if ( i < 0 )
  61                         return i;
  62         }
  63
  64         for ( i = 0 ; i < DRM_ARRAY_SIZE(dev->counts) ; i++ )
  65                 atomic_set( &dev->counts[i], 0 );
  66
  67         for ( i = 0 ; i < DRM_HASH_SIZE ; i++ ) {
  68                 dev->magiclist[i].head = NULL;
  69                 dev->magiclist[i].tail = NULL;
  70         }
  71
  72         dev->maplist = drm_alloc(sizeof(*dev->maplist),
  73                                   DRM_MEM_MAPS);
  74         if(dev->maplist == NULL) return -ENOMEM;
  75         memset(dev->maplist, 0, sizeof(*dev->maplist));
  76         INIT_LIST_HEAD(&dev->maplist->head);
  77
  78         dev->ctxlist = drm_alloc(sizeof(*dev->ctxlist),
  79                                   DRM_MEM_CTXLIST);
  80         if(dev->ctxlist == NULL) return -ENOMEM;
  81         memset(dev->ctxlist, 0, sizeof(*dev->ctxlist));
  82         INIT_LIST_HEAD(&dev->ctxlist->head);
  83
  84         dev->vmalist = NULL;
  85         dev->sigdata.lock = dev->lock.hw_lock = NULL;
  86         init_waitqueue_head( &dev->lock.lock_queue );
  87         dev->queue_count = 0;
  88         dev->queue_reserved = 0;
  89         dev->queue_slots = 0;
  90         dev->queuelist = NULL;
  91         dev->irq_enabled = 0;
  92         dev->context_flag = 0;
  93         dev->interrupt_flag = 0;
  94         dev->dma_flag = 0;
  95         dev->last_context = 0;
  96         dev->last_switch = 0;
  97         dev->last_checked = 0;
  98         init_waitqueue_head( &dev->context_wait );
  99         dev->if_version = 0;
 100
 101         dev->ctx_start = 0;
 102         dev->lck_start = 0;
 103
 104         dev->buf_rp = dev->buf;
 105         dev->buf_wp = dev->buf;
 106         dev->buf_end = dev->buf + DRM_BSZ;
 107         dev->buf_async = NULL;
 108         init_waitqueue_head( &dev->buf_readers );
 109         init_waitqueue_head( &dev->buf_writers );
 110
 111         DRM_DEBUG( "\n" );
 112
 113         /*
 114          * The kernel's context could be created here, but is now created
 115          * in drm_dma_enqueue.  This is more resource-efficient for
 116          * hardware that does not do DMA, but may mean that
 117          * drm_select_queue fails between the time the interrupt is
 118          * initialized and the time the queues are initialized.
 119          */
 120         if (dev->driver->postsetup)
 121                 dev->driver->postsetup(dev);
 122
 123         return 0;
 124 }
 125
 126 /**
 127  * Open file.
 128  *
 129  * \param inode device inode
 130  * \param filp file pointer.
 131  * \return zero on success or a negative number on failure.
 132  *
 133  * Searches the DRM device with the same minor number, calls open_helper(), and
 134  * increments the device open count. If the open count was previous at zero,
 135  * i.e., it's the first that the device is open, then calls setup().
 136  */
 137 int drm_open( struct inode *inode, struct file *filp )
 138 {
 139         drm_device_t *dev = NULL;
 140         int minor = iminor(inode);
 141         int retcode = 0;
 142
 143         if (!((minor >= 0) && (minor < drm_cards_limit)))
 144                 return -ENODEV;
 145
 146         if (!drm_heads[minor])
 147                 return -ENODEV;
 148
 149         if (!(dev = drm_heads[minor]->dev))
 150                 return -ENODEV;
 151
 152         retcode = drm_open_helper( inode, filp, dev );
 153         if ( !retcode ) {
 154                 atomic_inc( &dev->counts[_DRM_STAT_OPENS] );
 155                 spin_lock( &dev->count_lock );
 156                 if ( !dev->open_count++ ) {
 157                         spin_unlock( &dev->count_lock );
 158                         return drm_setup( dev );
 159                 }
 160                 spin_unlock( &dev->count_lock );
 161         }
 162
 163         return retcode;
 164 }
 165 EXPORT_SYMBOL(drm_open);
 166
 167 /**
 168  * Release file.
 169  *
 170  * \param inode device inode
 171  * \param filp file pointer.
 172  * \return zero on success or a negative number on failure.
 173  *
 174  * If the hardware lock is held then free it, and take it again for the kernel
 175  * context since it's necessary to reclaim buffers. Unlink the file private
 176  * data from its list and free it. Decreases the open count and if it reaches
 177  * zero calls takedown().
 178  */
 179 int drm_release( struct inode *inode, struct file *filp )
 180 {
 181         drm_file_t *priv = filp->private_data;
 182         drm_device_t *dev;
 183         int retcode = 0;
 184
 185         lock_kernel();
 186         dev = priv->head->dev;
 187
 188         DRM_DEBUG( "open_count = %d\n", dev->open_count );
 189
 190         if (dev->driver->prerelease)
 191                 dev->driver->prerelease(dev, filp);
 192
 193         /* ========================================================
 194          * Begin inline drm_release
 195          */
 196
 197         DRM_DEBUG( "pid = %d, device = 0x%lx, open_count = %d\n",
 198                    current->pid, (long)old_encode_dev(priv->head->device), dev->open_count );
 199
 200         if ( priv->lock_count && dev->lock.hw_lock &&
 201              _DRM_LOCK_IS_HELD(dev->lock.hw_lock->lock) &&
 202              dev->lock.filp == filp ) {
 203                 DRM_DEBUG( "File %p released, freeing lock for context %d\n",
 204                         filp,
 205                         _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
 206
 207                 if (dev->driver->release)
 208                         dev->driver->release(dev, filp);
 209
 210                 drm_lock_free( dev, &dev->lock.hw_lock->lock,
 211                                 _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock) );
 212
 213                                 /* FIXME: may require heavy-handed reset of
 214                                    hardware at this point, possibly
 215                                    processed via a callback to the X
 216                                    server. */
 217         }
 218         else if ( dev->driver->release && priv->lock_count && dev->lock.hw_lock ) {
 219                 /* The lock is required to reclaim buffers */
 220                 DECLARE_WAITQUEUE( entry, current );
 221
 222                 add_wait_queue( &dev->lock.lock_queue, &entry );
 223                 for (;;) {
 224                         __set_current_state(TASK_INTERRUPTIBLE);
 225                         if ( !dev->lock.hw_lock ) {
 226                                 /* Device has been unregistered */
 227                                 retcode = -EINTR;
 228                                 break;
 229                         }
 230                         if ( drm_lock_take( &dev->lock.hw_lock->lock,
 231                                              DRM_KERNEL_CONTEXT ) ) {
 232                                 dev->lock.filp      = filp;
 233                                 dev->lock.lock_time = jiffies;
 234                                 atomic_inc( &dev->counts[_DRM_STAT_LOCKS] );
 235                                 break;  /* Got lock */
 236                         }
 237                                 /* Contention */
 238                         schedule();
 239                         if ( signal_pending( current ) ) {
 240                                 retcode = -ERESTARTSYS;
 241                                 break;
 242                         }
 243                 }
 244                 __set_current_state(TASK_RUNNING);
 245                 remove_wait_queue( &dev->lock.lock_queue, &entry );
 246                 if( !retcode ) {
 247                         if (dev->driver->release)
 248                                 dev->driver->release(dev, filp);
 249                         drm_lock_free( dev, &dev->lock.hw_lock->lock,
 250                                         DRM_KERNEL_CONTEXT );
 251                 }
 252         }
 253
 254         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
 255         {
 256                 dev->driver->reclaim_buffers(dev, filp);
 257         }
 258
 259         drm_fasync( -1, filp, 0 );
 260
 261         down( &dev->ctxlist_sem );
 262         if ( !list_empty( &dev->ctxlist->head ) ) {
 263                 drm_ctx_list_t *pos, *n;
 264
 265                 list_for_each_entry_safe( pos, n, &dev->ctxlist->head, head ) {
 266                         if ( pos->tag == priv &&
 267                              pos->handle != DRM_KERNEL_CONTEXT ) {
 268                                 if (dev->driver->context_dtor)
 269                                         dev->driver->context_dtor(dev, pos->handle);
 270
 271                                 drm_ctxbitmap_free( dev, pos->handle );
 272
 273                                 list_del( &pos->head );
 274                                 drm_free( pos, sizeof(*pos), DRM_MEM_CTXLIST );
 275                                 --dev->ctx_count;
 276                         }
 277                 }
 278         }
 279         up( &dev->ctxlist_sem );
 280
 281         down( &dev->struct_sem );
 282         if ( priv->remove_auth_on_close == 1 ) {
 283                 drm_file_t *temp = dev->file_first;
 284                 while ( temp ) {
 285                         temp->authenticated = 0;
 286                         temp = temp->next;
 287                 }
 288         }
 289         if ( priv->prev ) {
 290                 priv->prev->next = priv->next;
 291         } else {
 292                 dev->file_first  = priv->next;
 293         }
 294         if ( priv->next ) {
 295                 priv->next->prev = priv->prev;
 296         } else {
 297                 dev->file_last   = priv->prev;
 298         }
 299         up( &dev->struct_sem );
 300
 301         if (dev->driver->free_filp_priv)
 302                 dev->driver->free_filp_priv(dev, priv);
 303
 304         drm_free( priv, sizeof(*priv), DRM_MEM_FILES );
 305
 306         /* ========================================================
 307          * End inline drm_release
 308          */
 309
 310         atomic_inc( &dev->counts[_DRM_STAT_CLOSES] );
 311         spin_lock( &dev->count_lock );
 312         if ( !--dev->open_count ) {
 313                 if ( atomic_read( &dev->ioctl_count ) || dev->blocked ) {
 314                         DRM_ERROR( "Device busy: %d %d\n",
 315                                    atomic_read( &dev->ioctl_count ),
 316                                    dev->blocked );
 317                         spin_unlock( &dev->count_lock );
 318                         unlock_kernel();
 319                         return -EBUSY;
 320                 }
 321                 spin_unlock( &dev->count_lock );
 322                 unlock_kernel();
 323                 return drm_takedown( dev );
 324         }
 325         spin_unlock( &dev->count_lock );
 326
 327         unlock_kernel();
 328
 329         return retcode;
 330 }
 331 EXPORT_SYMBOL(drm_release);
 332
 333 /**
 334  * Called whenever a process opens /dev/drm.
 335  *
 336  * \param inode device inode.
 337  * \param filp file pointer.
 338  * \param dev device.
 339  * \return zero on success or a negative number on failure.
 340  *
 341  * Creates and initializes a drm_file structure for the file private data in \p
 342  * filp and add it into the double linked list in \p dev.
 343  */
 344 int drm_open_helper(struct inode *inode, struct file *filp, drm_device_t *dev)
 345 {
 346         int          minor = iminor(inode);
 347         drm_file_t   *priv;
 348         int ret;
 349
 350         if (filp->f_flags & O_EXCL)   return -EBUSY; /* No exclusive opens */
 351         if (!drm_cpu_valid())        return -EINVAL;
 352
 353         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
 354
 355         priv                = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 356         if(!priv) return -ENOMEM;
 357
 358         memset(priv, 0, sizeof(*priv));
 359         filp->private_data  = priv;
 360         priv->uid           = current->euid;
 361         priv->pid           = current->pid;
 362         priv->minor         = minor;
 363         priv->head          = drm_heads[minor];
 364         priv->ioctl_count   = 0;
 365         priv->authenticated = capable(CAP_SYS_ADMIN);
 366         priv->lock_count    = 0;
 367
 368         if (dev->driver->open_helper) {
 369                 ret=dev->driver->open_helper(dev, priv);
 370                 if (ret < 0)
 371                         goto out_free;
 372         }
 373
 374         down(&dev->struct_sem);
 375         if (!dev->file_last) {
 376                 priv->next      = NULL;
 377                 priv->prev      = NULL;
 378                 dev->file_first = priv;
 379                 dev->file_last  = priv;
 380         } else {
 381                 priv->next           = NULL;
 382                 priv->prev           = dev->file_last;
 383                 dev->file_last->next = priv;
 384                 dev->file_last       = priv;
 385         }
 386         up(&dev->struct_sem);
 387
 388 #ifdef __alpha__
 389         /*
 390          * Default the hose
 391          */
 392         if (!dev->hose) {
 393                 struct pci_dev *pci_dev;
 394                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 395                 if (pci_dev) {
 396                         dev->hose = pci_dev->sysdata;
 397                         pci_dev_put(pci_dev);
 398                 }
 399                 if (!dev->hose) {
 400                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 401                         if (b) dev->hose = b->sysdata;
 402                 }
 403         }
 404 #endif
 405
 406         return 0;
 407 out_free:
 408         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 409         filp->private_data=NULL;
 410         return ret;
 411 }
 412
 413 /** No-op. */
 414 int drm_flush(struct file *filp)
 415 {
 416         drm_file_t    *priv   = filp->private_data;
 417         drm_device_t  *dev    = priv->head->dev;
 418
 419         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 420                   current->pid, (long)old_encode_dev(priv->head->device), dev->open_count);
 421         return 0;
 422 }
 423 EXPORT_SYMBOL(drm_flush);
 424
 425 /** No-op. */
 426 int drm_fasync(int fd, struct file *filp, int on)
 427 {
 428         drm_file_t    *priv   = filp->private_data;
 429         drm_device_t  *dev    = priv->head->dev;
 430         int           retcode;
 431
 432         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, (long)old_encode_dev(priv->head->device));
 433         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 434         if (retcode < 0) return retcode;
 435         return 0;
 436 }
 437 EXPORT_SYMBOL(drm_fasync);
 438
 439 /** No-op. */
 440 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 441 {
 442         return 0;
 443 }
 444 EXPORT_SYMBOL(drm_poll);
 445
 446
 447 /** No-op. */
 448 ssize_t drm_read(struct file *filp, char __user *buf, size_t count, loff_t *off)
 449 {
 450         return 0;
 451 }