git.oblomov.eu Git - linux-2.6/blob - 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         int i;
  48         int ret;
  49
  50         if (dev->driver->firstopen) {
  51                 ret = dev->driver->firstopen(dev);
  52                 if (ret != 0)
  53                         return ret;
  54         }
  55
  56         atomic_set(&dev->ioctl_count, 0);
  57         atomic_set(&dev->vma_count, 0);
  58         dev->buf_use = 0;
  59         atomic_set(&dev->buf_alloc, 0);
  60
  61         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) {
  62                 i = drm_dma_setup(dev);
  63                 if (i < 0)
  64                         return i;
  65         }
  66
  67         for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
  68                 atomic_set(&dev->counts[i], 0);
  69
  70         dev->sigdata.lock = NULL;
  71
  72         dev->queue_count = 0;
  73         dev->queue_reserved = 0;
  74         dev->queue_slots = 0;
  75         dev->queuelist = NULL;
  76         dev->context_flag = 0;
  77         dev->interrupt_flag = 0;
  78         dev->dma_flag = 0;
  79         dev->last_context = 0;
  80         dev->last_switch = 0;
  81         dev->last_checked = 0;
  82         init_waitqueue_head(&dev->context_wait);
  83         dev->if_version = 0;
  84
  85         dev->ctx_start = 0;
  86         dev->lck_start = 0;
  87
  88         dev->buf_async = NULL;
  89         init_waitqueue_head(&dev->buf_readers);
  90         init_waitqueue_head(&dev->buf_writers);
  91
  92         DRM_DEBUG("\n");
  93
  94         /*
  95          * The kernel's context could be created here, but is now created
  96          * in drm_dma_enqueue.  This is more resource-efficient for
  97          * hardware that does not do DMA, but may mean that
  98          * drm_select_queue fails between the time the interrupt is
  99          * initialized and the time the queues are initialized.
 100          */
 101
 102         return 0;
 103 }
 104
 105 /**
 106  * Open file.
 107  *
 108  * \param inode device inode
 109  * \param filp file pointer.
 110  * \return zero on success or a negative number on failure.
 111  *
 112  * Searches the DRM device with the same minor number, calls open_helper(), and
 113  * increments the device open count. If the open count was previous at zero,
 114  * i.e., it's the first that the device is open, then calls setup().
 115  */
 116 int drm_open(struct inode *inode, struct file *filp)
 117 {
 118         struct drm_device *dev = NULL;
 119         int minor_id = iminor(inode);
 120         struct drm_minor *minor;
 121         int retcode = 0;
 122
 123         minor = idr_find(&drm_minors_idr, minor_id);
 124         if (!minor)
 125                 return -ENODEV;
 126
 127         if (!(dev = minor->dev))
 128                 return -ENODEV;
 129
 130         retcode = drm_open_helper(inode, filp, dev);
 131         if (!retcode) {
 132                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
 133                 spin_lock(&dev->count_lock);
 134                 if (!dev->open_count++) {
 135                         spin_unlock(&dev->count_lock);
 136                         retcode = drm_setup(dev);
 137                         goto out;
 138                 }
 139                 spin_unlock(&dev->count_lock);
 140         }
 141
 142 out:
 143         mutex_lock(&dev->struct_mutex);
 144         if (dev->dev_mapping == NULL)
 145                 dev->dev_mapping = inode->i_mapping;
 146         else if (dev->dev_mapping != inode->i_mapping)
 147                 WARN(1, "dev->dev_mapping not inode mapping (%p expected %p)\n",
 148                      dev->dev_mapping, inode->i_mapping);
 149         mutex_unlock(&dev->struct_mutex);
 150
 151         return retcode;
 152 }
 153 EXPORT_SYMBOL(drm_open);
 154
 155 /**
 156  * File \c open operation.
 157  *
 158  * \param inode device inode.
 159  * \param filp file pointer.
 160  *
 161  * Puts the dev->fops corresponding to the device minor number into
 162  * \p filp, call the \c open method, and restore the file operations.
 163  */
 164 int drm_stub_open(struct inode *inode, struct file *filp)
 165 {
 166         struct drm_device *dev = NULL;
 167         struct drm_minor *minor;
 168         int minor_id = iminor(inode);
 169         int err = -ENODEV;
 170         const struct file_operations *old_fops;
 171
 172         DRM_DEBUG("\n");
 173
 174         /* BKL pushdown: note that nothing else serializes idr_find() */
 175         lock_kernel();
 176         minor = idr_find(&drm_minors_idr, minor_id);
 177         if (!minor)
 178                 goto out;
 179
 180         if (!(dev = minor->dev))
 181                 goto out;
 182
 183         old_fops = filp->f_op;
 184         filp->f_op = fops_get(&dev->driver->fops);
 185         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 186                 fops_put(filp->f_op);
 187                 filp->f_op = fops_get(old_fops);
 188         }
 189         fops_put(old_fops);
 190
 191 out:
 192         unlock_kernel();
 193         return err;
 194 }
 195
 196 /**
 197  * Check whether DRI will run on this CPU.
 198  *
 199  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 200  */
 201 static int drm_cpu_valid(void)
 202 {
 203 #if defined(__i386__)
 204         if (boot_cpu_data.x86 == 3)
 205                 return 0;       /* No cmpxchg on a 386 */
 206 #endif
 207 #if defined(__sparc__) && !defined(__sparc_v9__)
 208         return 0;               /* No cmpxchg before v9 sparc. */
 209 #endif
 210         return 1;
 211 }
 212
 213 /**
 214  * Called whenever a process opens /dev/drm.
 215  *
 216  * \param inode device inode.
 217  * \param filp file pointer.
 218  * \param dev device.
 219  * \return zero on success or a negative number on failure.
 220  *
 221  * Creates and initializes a drm_file structure for the file private data in \p
 222  * filp and add it into the double linked list in \p dev.
 223  */
 224 static int drm_open_helper(struct inode *inode, struct file *filp,
 225                            struct drm_device * dev)
 226 {
 227         int minor_id = iminor(inode);
 228         struct drm_file *priv;
 229         int ret;
 230
 231         if (filp->f_flags & O_EXCL)
 232                 return -EBUSY;  /* No exclusive opens */
 233         if (!drm_cpu_valid())
 234                 return -EINVAL;
 235
 236         DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id);
 237
 238         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 239         if (!priv)
 240                 return -ENOMEM;
 241
 242         memset(priv, 0, sizeof(*priv));
 243         filp->private_data = priv;
 244         priv->filp = filp;
 245         priv->uid = current_euid();
 246         priv->pid = task_pid_nr(current);
 247         priv->minor = idr_find(&drm_minors_idr, minor_id);
 248         priv->ioctl_count = 0;
 249         /* for compatibility root is always authenticated */
 250         priv->authenticated = capable(CAP_SYS_ADMIN);
 251         priv->lock_count = 0;
 252
 253         INIT_LIST_HEAD(&priv->lhead);
 254
 255         if (dev->driver->driver_features & DRIVER_GEM)
 256                 drm_gem_open(dev, priv);
 257
 258         if (dev->driver->open) {
 259                 ret = dev->driver->open(dev, priv);
 260                 if (ret < 0)
 261                         goto out_free;
 262         }
 263
 264
 265         /* if there is no current master make this fd it */
 266         mutex_lock(&dev->struct_mutex);
 267         if (!priv->minor->master) {
 268                 /* create a new master */
 269                 priv->minor->master = drm_master_create(priv->minor);
 270                 if (!priv->minor->master) {
 271                         ret = -ENOMEM;
 272                         goto out_free;
 273                 }
 274
 275                 priv->is_master = 1;
 276                 /* take another reference for the copy in the local file priv */
 277                 priv->master = drm_master_get(priv->minor->master);
 278
 279                 priv->authenticated = 1;
 280
 281                 mutex_unlock(&dev->struct_mutex);
 282                 if (dev->driver->master_create) {
 283                         ret = dev->driver->master_create(dev, priv->master);
 284                         if (ret) {
 285                                 mutex_lock(&dev->struct_mutex);
 286                                 /* drop both references if this fails */
 287                                 drm_master_put(&priv->minor->master);
 288                                 drm_master_put(&priv->master);
 289                                 mutex_unlock(&dev->struct_mutex);
 290                                 goto out_free;
 291                         }
 292                 }
 293         } else {
 294                 /* get a reference to the master */
 295                 priv->master = drm_master_get(priv->minor->master);
 296                 mutex_unlock(&dev->struct_mutex);
 297         }
 298
 299         mutex_lock(&dev->struct_mutex);
 300         list_add(&priv->lhead, &dev->filelist);
 301         mutex_unlock(&dev->struct_mutex);
 302
 303 #ifdef __alpha__
 304         /*
 305          * Default the hose
 306          */
 307         if (!dev->hose) {
 308                 struct pci_dev *pci_dev;
 309                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 310                 if (pci_dev) {
 311                         dev->hose = pci_dev->sysdata;
 312                         pci_dev_put(pci_dev);
 313                 }
 314                 if (!dev->hose) {
 315                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 316                         if (b)
 317                                 dev->hose = b->sysdata;
 318                 }
 319         }
 320 #endif
 321
 322         return 0;
 323       out_free:
 324         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 325         filp->private_data = NULL;
 326         return ret;
 327 }
 328
 329 /** No-op. */
 330 int drm_fasync(int fd, struct file *filp, int on)
 331 {
 332         struct drm_file *priv = filp->private_data;
 333         struct drm_device *dev = priv->minor->dev;
 334         int retcode;
 335
 336         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
 337                   (long)old_encode_dev(priv->minor->device));
 338         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 339         if (retcode < 0)
 340                 return retcode;
 341         return 0;
 342 }
 343 EXPORT_SYMBOL(drm_fasync);
 344
 345 /*
 346  * Reclaim locked buffers; note that this may be a bad idea if the current
 347  * context doesn't have the hw lock...
 348  */
 349 static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f)
 350 {
 351         struct drm_file *file_priv = f->private_data;
 352
 353         if (drm_i_have_hw_lock(dev, file_priv)) {
 354                 dev->driver->reclaim_buffers_locked(dev, file_priv);
 355         } else {
 356                 unsigned long _end = jiffies + 3 * DRM_HZ;
 357                 int locked = 0;
 358
 359                 drm_idlelock_take(&file_priv->master->lock);
 360
 361                 /*
 362                  * Wait for a while.
 363                  */
 364                 do {
 365                         spin_lock_bh(&file_priv->master->lock.spinlock);
 366                         locked = file_priv->master->lock.idle_has_lock;
 367                         spin_unlock_bh(&file_priv->master->lock.spinlock);
 368                         if (locked)
 369                                 break;
 370                         schedule();
 371                 } while (!time_after_eq(jiffies, _end));
 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(&file_priv->master->lock);
 381         }
 382 }
 383
 384 static void drm_master_release(struct drm_device *dev, struct file *filp)
 385 {
 386         struct drm_file *file_priv = filp->private_data;
 387
 388         if (dev->driver->reclaim_buffers_locked &&
 389             file_priv->master->lock.hw_lock)
 390                 drm_reclaim_locked_buffers(dev, filp);
 391
 392         if (dev->driver->reclaim_buffers_idlelocked &&
 393             file_priv->master->lock.hw_lock) {
 394                 drm_idlelock_take(&file_priv->master->lock);
 395                 dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
 396                 drm_idlelock_release(&file_priv->master->lock);
 397         }
 398
 399
 400         if (drm_i_have_hw_lock(dev, file_priv)) {
 401                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
 402                           filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
 403                 drm_lock_free(&file_priv->master->lock,
 404                               _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
 405         }
 406
 407         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 408             !dev->driver->reclaim_buffers_locked) {
 409                 dev->driver->reclaim_buffers(dev, file_priv);
 410         }
 411 }
 412
 413 /**
 414  * Release file.
 415  *
 416  * \param inode device inode
 417  * \param file_priv DRM file private.
 418  * \return zero on success or a negative number on failure.
 419  *
 420  * If the hardware lock is held then free it, and take it again for the kernel
 421  * context since it's necessary to reclaim buffers. Unlink the file private
 422  * data from its list and free it. Decreases the open count and if it reaches
 423  * zero calls drm_lastclose().
 424  */
 425 int drm_release(struct inode *inode, struct file *filp)
 426 {
 427         struct drm_file *file_priv = filp->private_data;
 428         struct drm_device *dev = file_priv->minor->dev;
 429         int retcode = 0;
 430
 431         lock_kernel();
 432
 433         DRM_DEBUG("open_count = %d\n", dev->open_count);
 434
 435         if (dev->driver->preclose)
 436                 dev->driver->preclose(dev, file_priv);
 437
 438         /* ========================================================
 439          * Begin inline drm_release
 440          */
 441
 442         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 443                   task_pid_nr(current),
 444                   (long)old_encode_dev(file_priv->minor->device),
 445                   dev->open_count);
 446
 447         /* if the master has gone away we can't do anything with the lock */
 448         if (file_priv->minor->master)
 449                 drm_master_release(dev, filp);
 450
 451         if (dev->driver->driver_features & DRIVER_GEM)
 452                 drm_gem_release(dev, file_priv);
 453
 454         mutex_lock(&dev->ctxlist_mutex);
 455         if (!list_empty(&dev->ctxlist)) {
 456                 struct drm_ctx_list *pos, *n;
 457
 458                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
 459                         if (pos->tag == file_priv &&
 460                             pos->handle != DRM_KERNEL_CONTEXT) {
 461                                 if (dev->driver->context_dtor)
 462                                         dev->driver->context_dtor(dev,
 463                                                                   pos->handle);
 464
 465                                 drm_ctxbitmap_free(dev, pos->handle);
 466
 467                                 list_del(&pos->head);
 468                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
 469                                 --dev->ctx_count;
 470                         }
 471                 }
 472         }
 473         mutex_unlock(&dev->ctxlist_mutex);
 474
 475         mutex_lock(&dev->struct_mutex);
 476
 477         if (file_priv->is_master) {
 478                 struct drm_file *temp;
 479                 list_for_each_entry(temp, &dev->filelist, lhead) {
 480                         if ((temp->master == file_priv->master) &&
 481                             (temp != file_priv))
 482                                 temp->authenticated = 0;
 483                 }
 484
 485                 if (file_priv->minor->master == file_priv->master) {
 486                         /* drop the reference held my the minor */
 487                         drm_master_put(&file_priv->minor->master);
 488                 }
 489         }
 490
 491         /* drop the reference held my the file priv */
 492         drm_master_put(&file_priv->master);
 493         file_priv->is_master = 0;
 494         list_del(&file_priv->lhead);
 495         mutex_unlock(&dev->struct_mutex);
 496
 497         if (dev->driver->postclose)
 498                 dev->driver->postclose(dev, file_priv);
 499         drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES);
 500
 501         /* ========================================================
 502          * End inline drm_release
 503          */
 504
 505         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 506         spin_lock(&dev->count_lock);
 507         if (!--dev->open_count) {
 508                 if (atomic_read(&dev->ioctl_count)) {
 509                         DRM_ERROR("Device busy: %d\n",
 510                                   atomic_read(&dev->ioctl_count));
 511                         spin_unlock(&dev->count_lock);
 512                         unlock_kernel();
 513                         return -EBUSY;
 514                 }
 515                 spin_unlock(&dev->count_lock);
 516                 unlock_kernel();
 517                 return drm_lastclose(dev);
 518         }
 519         spin_unlock(&dev->count_lock);
 520
 521         unlock_kernel();
 522
 523         return retcode;
 524 }
 525 EXPORT_SYMBOL(drm_release);
 526
 527 /** No-op. */
 528 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 529 {
 530         return 0;
 531 }
 532 EXPORT_SYMBOL(drm_poll);