linux-core/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         int i;
  47         int ret;
  48
  49         if (dev->driver->firstopen) {
  50                 ret = dev->driver->firstopen(dev);
  51                 if (ret != 0)
  52                         return ret;
  53         }
  54
  55         atomic_set(&dev->ioctl_count, 0);
  56         atomic_set(&dev->vma_count, 0);
  57         dev->buf_use = 0;
  58         atomic_set(&dev->buf_alloc, 0);
  59
  60         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) {
  61                 i = drm_dma_setup(dev);
  62                 if (i < 0)
  63                         return i;
  64         }
  65
  66         for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
  67                 atomic_set(&dev->counts[i], 0);
  68
  69         dev->sigdata.lock = NULL;
  70
  71         dev->queue_count = 0;
  72         dev->queue_reserved = 0;
  73         dev->queue_slots = 0;
  74         dev->queuelist = NULL;
  75         dev->context_flag = 0;
  76         dev->interrupt_flag = 0;
  77         dev->dma_flag = 0;
  78         dev->last_context = 0;
  79         dev->last_switch = 0;
  80         dev->last_checked = 0;
  81         init_waitqueue_head(&dev->context_wait);
  82         dev->if_version = 0;
  83
  84         dev->ctx_start = 0;
  85         dev->lck_start = 0;
  86
  87         dev->buf_async = NULL;
  88         init_waitqueue_head(&dev->buf_readers);
  89         init_waitqueue_head(&dev->buf_writers);
  90
  91         DRM_DEBUG("\n");
  92
  93         /*
  94          * The kernel's context could be created here, but is now created
  95          * in drm_dma_enqueue.  This is more resource-efficient for
  96          * hardware that does not do DMA, but may mean that
  97          * drm_select_queue fails between the time the interrupt is
  98          * initialized and the time the queues are initialized.
  99          */
 100
 101         return 0;
 102 }
 103
 104 /**
 105  * Open file.
 106  *
 107  * \param inode device inode
 108  * \param filp file pointer.
 109  * \return zero on success or a negative number on failure.
 110  *
 111  * Searches the DRM device with the same minor number, calls open_helper(), and
 112  * increments the device open count. If the open count was previous at zero,
 113  * i.e., it's the first that the device is open, then calls setup().
 114  */
 115 int drm_open(struct inode *inode, struct file *filp)
 116 {
 117         struct drm_device *dev = NULL;
 118         int minor_id = iminor(inode);
 119         struct drm_minor *minor;
 120         int retcode = 0;
 121
 122         minor = idr_find(&drm_minors_idr, minor_id);
 123         if (!minor)
 124                 return -ENODEV;
 125
 126         if (!(dev = minor->dev))
 127                 return -ENODEV;
 128
 129         retcode = drm_open_helper(inode, filp, dev);
 130         if (!retcode) {
 131                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
 132                 spin_lock(&dev->count_lock);
 133                 if (!dev->open_count++) {
 134                         spin_unlock(&dev->count_lock);
 135                         retcode = drm_setup(dev);
 136                         goto out;
 137                 }
 138                 spin_unlock(&dev->count_lock);
 139         }
 140
 141 out:
 142         mutex_lock(&dev->struct_mutex);
 143         BUG_ON((dev->dev_mapping != NULL) &&
 144                (dev->dev_mapping != inode->i_mapping));
 145         if (dev->dev_mapping == NULL)
 146                 dev->dev_mapping = inode->i_mapping;
 147         mutex_unlock(&dev->struct_mutex);
 148
 149         return retcode;
 150 }
 151 EXPORT_SYMBOL(drm_open);
 152
 153 /**
 154  * File \c open operation.
 155  *
 156  * \param inode device inode.
 157  * \param filp file pointer.
 158  *
 159  * Puts the dev->fops corresponding to the device minor number into
 160  * \p filp, call the \c open method, and restore the file operations.
 161  */
 162 int drm_stub_open(struct inode *inode, struct file *filp)
 163 {
 164         struct drm_device *dev = NULL;
 165         struct drm_minor *minor;
 166         int minor_id = iminor(inode);
 167         int err = -ENODEV;
 168         const struct file_operations *old_fops;
 169
 170         DRM_DEBUG("\n");
 171
 172         minor = idr_find(&drm_minors_idr, minor_id);
 173         if (!minor)
 174                 return -ENODEV;
 175
 176         if (!(dev = minor->dev))
 177                 return -ENODEV;
 178
 179         old_fops = filp->f_op;
 180         filp->f_op = fops_get(&dev->driver->fops);
 181         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 182                 fops_put(filp->f_op);
 183                 filp->f_op = fops_get(old_fops);
 184         }
 185         fops_put(old_fops);
 186
 187         return err;
 188 }
 189
 190 /**
 191  * Check whether DRI will run on this CPU.
 192  *
 193  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 194  */
 195 static int drm_cpu_valid(void)
 196 {
 197 #if defined(__i386__)
 198         if (boot_cpu_data.x86 == 3)
 199                 return 0;       /* No cmpxchg on a 386 */
 200 #endif
 201 #if defined(__sparc__) && !defined(__sparc_v9__)
 202         return 0;               /* No cmpxchg before v9 sparc. */
 203 #endif
 204         return 1;
 205 }
 206
 207 /**
 208  * Called whenever a process opens /dev/drm.
 209  *
 210  * \param inode device inode.
 211  * \param filp file pointer.
 212  * \param dev device.
 213  * \return zero on success or a negative number on failure.
 214  *
 215  * Creates and initializes a drm_file structure for the file private data in \p
 216  * filp and add it into the double linked list in \p dev.
 217  */
 218 static int drm_open_helper(struct inode *inode, struct file *filp,
 219                            struct drm_device * dev)
 220 {
 221         int minor_id = iminor(inode);
 222         struct drm_file *priv;
 223         int ret;
 224         int i, j;
 225
 226         if (filp->f_flags & O_EXCL)
 227                 return -EBUSY;  /* No exclusive opens */
 228         if (!drm_cpu_valid())
 229                 return -EINVAL;
 230
 231         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor_id);
 232
 233         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 234         if (!priv)
 235                 return -ENOMEM;
 236
 237         memset(priv, 0, sizeof(*priv));
 238         filp->private_data = priv;
 239         priv->filp = filp;
 240         priv->uid = current->euid;
 241         priv->pid = current->pid;
 242         priv->minor = idr_find(&drm_minors_idr, minor_id);
 243         priv->ioctl_count = 0;
 244         /* for compatibility root is always authenticated */
 245         priv->authenticated = capable(CAP_SYS_ADMIN);
 246         priv->lock_count = 0;
 247
 248         INIT_LIST_HEAD(&priv->lhead);
 249         INIT_LIST_HEAD(&priv->refd_objects);
 250         INIT_LIST_HEAD(&priv->fbs);
 251
 252         for (i = 0; i < _DRM_NO_REF_TYPES; ++i) {
 253                 ret = drm_ht_create(&priv->refd_object_hash[i],
 254                                     DRM_FILE_HASH_ORDER);
 255                 if (ret)
 256                         break;
 257         }
 258
 259         if (ret) {
 260                 for (j = 0; j < i; ++j)
 261                         drm_ht_remove(&priv->refd_object_hash[j]);
 262                 goto out_free;
 263         }
 264
 265         if (dev->driver->open) {
 266                 ret = dev->driver->open(dev, priv);
 267                 if (ret < 0)
 268                         goto out_free;
 269         }
 270
 271
 272         /* if there is no current master make this fd it */
 273         mutex_lock(&dev->struct_mutex);
 274         if (!priv->minor->master) {
 275                 priv->minor->master = drm_get_master(priv->minor);
 276                 if (!priv->minor->master) {
 277                         ret = -ENOMEM;
 278                         goto out_free;
 279                 }
 280
 281                 priv->is_master = 1;
 282                 priv->master = priv->minor->master;
 283
 284                 priv->authenticated = 1;
 285                 mutex_unlock(&dev->struct_mutex);
 286                 if (dev->driver->master_create) {
 287                         ret = dev->driver->master_create(dev, priv->master);
 288                         if (ret) {
 289                                 drm_put_master(priv->minor->master);
 290                                 priv->minor->master = priv->master = NULL;
 291                                 mutex_unlock(&dev->struct_mutex);
 292                                 goto out_free;
 293                         }
 294                 }
 295         } else {
 296                 priv->master = priv->minor->master;
 297                 mutex_unlock(&dev->struct_mutex);
 298         }
 299
 300         mutex_lock(&dev->struct_mutex);
 301         list_add(&priv->lhead, &dev->filelist);
 302         mutex_unlock(&dev->struct_mutex);
 303
 304 #ifdef __alpha__
 305         /*
 306          * Default the hose
 307          */
 308         if (!dev->hose) {
 309                 struct pci_dev *pci_dev;
 310                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 311                 if (pci_dev) {
 312                         dev->hose = pci_dev->sysdata;
 313                         pci_dev_put(pci_dev);
 314                 }
 315                 if (!dev->hose) {
 316                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 317                         if (b)
 318                                 dev->hose = b->sysdata;
 319                 }
 320         }
 321 #endif
 322
 323         return 0;
 324       out_free:
 325         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 326         filp->private_data = NULL;
 327         return ret;
 328 }
 329
 330 /** No-op. */
 331 int drm_fasync(int fd, struct file *filp, int on)
 332 {
 333         struct drm_file *priv = filp->private_data;
 334         struct drm_device *dev = priv->minor->dev;
 335         int retcode;
 336
 337         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
 338                   (long)old_encode_dev(priv->minor->device));
 339         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 340         if (retcode < 0)
 341                 return retcode;
 342         return 0;
 343 }
 344 EXPORT_SYMBOL(drm_fasync);
 345
 346 static void drm_object_release(struct file *filp)
 347 {
 348         struct drm_file *priv = filp->private_data;
 349         struct list_head *head;
 350         struct drm_ref_object *ref_object;
 351         int i;
 352
 353         /*
 354          * Free leftover ref objects created by me. Note that we cannot use
 355          * list_for_each() here, as the struct_mutex may be temporarily
 356          * released by the remove_() functions, and thus the lists may be
 357          * altered.
 358          * Also, a drm_remove_ref_object() will not remove it
 359          * from the list unless its refcount is 1.
 360          */
 361
 362         head = &priv->refd_objects;
 363         while (head->next != head) {
 364                 ref_object = list_entry(head->next, struct drm_ref_object, list);
 365                 drm_remove_ref_object(priv, ref_object);
 366                 head = &priv->refd_objects;
 367         }
 368
 369         for (i = 0; i < _DRM_NO_REF_TYPES; ++i)
 370                 drm_ht_remove(&priv->refd_object_hash[i]);
 371 }
 372
 373 /**
 374  * Release file.
 375  *
 376  * \param inode device inode
 377  * \param file_priv DRM file private.
 378  * \return zero on success or a negative number on failure.
 379  *
 380  * If the hardware lock is held then free it, and take it again for the kernel
 381  * context since it's necessary to reclaim buffers. Unlink the file private
 382  * data from its list and free it. Decreases the open count and if it reaches
 383  * zero calls drm_lastclose().
 384  */
 385 int drm_release(struct inode *inode, struct file *filp)
 386 {
 387         struct drm_file *file_priv = filp->private_data;
 388         struct drm_device *dev = file_priv->minor->dev;
 389         int retcode = 0;
 390
 391         lock_kernel();
 392
 393         DRM_DEBUG("open_count = %d\n", dev->open_count);
 394
 395         if (dev->driver->preclose)
 396                 dev->driver->preclose(dev, file_priv);
 397
 398         /* ========================================================
 399          * Begin inline drm_release
 400          */
 401
 402         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 403                   current->pid, (long)old_encode_dev(file_priv->minor->device),
 404                   dev->open_count);
 405
 406         /* if the master has gone away we can't do anything with the lock */
 407         if (file_priv->minor->master) {
 408                 if (dev->driver->reclaim_buffers_locked && file_priv->master->lock.hw_lock) {
 409                         if (drm_i_have_hw_lock(dev, file_priv)) {
 410                                 dev->driver->reclaim_buffers_locked(dev, file_priv);
 411                         } else {
 412                                 unsigned long _end=jiffies + 3*DRM_HZ;
 413                                 int locked = 0;
 414
 415                                 drm_idlelock_take(&file_priv->master->lock);
 416
 417                                 /*
 418                                  * Wait for a while.
 419                                  */
 420
 421                                 do{
 422                                         spin_lock_bh(&file_priv->master->lock.spinlock);
 423                                         locked = file_priv->master->lock.idle_has_lock;
 424                                         spin_unlock_bh(&file_priv->master->lock.spinlock);
 425                                         if (locked)
 426                                                 break;
 427                                         schedule();
 428                                 } while (!time_after_eq(jiffies, _end));
 429
 430                                 if (!locked) {
 431                                         DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
 432                                                   "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
 433                                                   "\tI will go on reclaiming the buffers anyway.\n");
 434                                 }
 435
 436                                 dev->driver->reclaim_buffers_locked(dev, file_priv);
 437                                 drm_idlelock_release(&file_priv->master->lock);
 438                         }
 439                 }
 440
 441                 if (dev->driver->reclaim_buffers_idlelocked && file_priv->master->lock.hw_lock) {
 442
 443                         drm_idlelock_take(&file_priv->master->lock);
 444                         dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
 445                         drm_idlelock_release(&file_priv->master->lock);
 446
 447                 }
 448
 449
 450                 if (drm_i_have_hw_lock(dev, file_priv)) {
 451                         DRM_DEBUG("File %p released, freeing lock for context %d\n",
 452                                   filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
 453
 454                         drm_lock_free(&file_priv->master->lock,
 455                                       _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
 456                 }
 457
 458
 459                 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 460                     !dev->driver->reclaim_buffers_locked) {
 461                         dev->driver->reclaim_buffers(dev, file_priv);
 462                 }
 463         }
 464
 465         drm_fasync(-1, filp, 0);
 466
 467         mutex_lock(&dev->ctxlist_mutex);
 468
 469         if (!list_empty(&dev->ctxlist)) {
 470                 struct drm_ctx_list *pos, *n;
 471
 472                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
 473                         if (pos->tag == file_priv &&
 474                             pos->handle != DRM_KERNEL_CONTEXT) {
 475                                 if (dev->driver->context_dtor)
 476                                         dev->driver->context_dtor(dev,
 477                                                                   pos->handle);
 478
 479                                 drm_ctxbitmap_free(dev, pos->handle);
 480
 481                                 list_del(&pos->head);
 482                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
 483                                 --dev->ctx_count;
 484                         }
 485                 }
 486         }
 487         mutex_unlock(&dev->ctxlist_mutex);
 488
 489         if (drm_core_check_feature(dev, DRIVER_MODESET))
 490                 drm_fb_release(filp);
 491
 492         if (file_priv->is_master) {
 493                 struct drm_file *temp;
 494                 list_for_each_entry(temp, &dev->filelist, lhead) {
 495                         if ((temp->master == file_priv->master) &&
 496                             (temp != file_priv))
 497                                 temp->authenticated = 0;
 498                 }
 499
 500                 if (file_priv->minor->master == file_priv->master)
 501                         file_priv->minor->master = NULL;
 502                 drm_put_master(file_priv->master);
 503         }
 504
 505         file_priv->master = NULL;
 506         file_priv->is_master = 0;
 507
 508         mutex_lock(&dev->struct_mutex);
 509         drm_object_release(filp);
 510
 511         list_del(&file_priv->lhead);
 512
 513         mutex_unlock(&dev->struct_mutex);
 514
 515         if (dev->driver->postclose)
 516                 dev->driver->postclose(dev, file_priv);
 517         drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES);
 518
 519         /* ========================================================
 520          * End inline drm_release
 521          */
 522
 523         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 524         spin_lock(&dev->count_lock);
 525         if (!--dev->open_count) {
 526                 if (atomic_read(&dev->ioctl_count)) {
 527                         DRM_ERROR("Device busy: %d\n",
 528                                   atomic_read(&dev->ioctl_count));
 529                         spin_unlock(&dev->count_lock);
 530                         unlock_kernel();
 531                         return -EBUSY;
 532                 }
 533                 spin_unlock(&dev->count_lock);
 534                 unlock_kernel();
 535                 return drm_lastclose(dev);
 536         }
 537         spin_unlock(&dev->count_lock);
 538
 539         unlock_kernel();
 540
 541         return retcode;
 542 }
 543 EXPORT_SYMBOL(drm_release);
 544
 545 /** No-op. */
 546 /* This is to deal with older X servers that believe 0 means data is
 547  * available which is not the correct return for a poll function.
 548  * This cannot be fixed until the Xserver is fixed. Xserver will need
 549  * to set a newer interface version to avoid breaking older Xservers.
 550  * Without fixing the Xserver you get: "WaitForSomething(): select: errno=22"
 551  * http://freedesktop.org/bugzilla/show_bug.cgi?id=1505 if you try
 552  * to return the correct response.
 553  */
 554 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 555 {
 556         /* return (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM); */
 557         return 0;
 558 }
 559 EXPORT_SYMBOL(drm_poll);