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                            drm_device_t * dev);
  43
  44 static int drm_setup(drm_device_t * dev)
  45 {
  46         drm_local_map_t *map;
  47         int i;
  48         int ret;
  49         int sareapage;
  50
  51         if (dev->driver->firstopen) {
  52                 ret = dev->driver->firstopen(dev);
  53                 if (ret != 0)
  54                         return ret;
  55         }
  56
  57         dev->magicfree.next = NULL;
  58
  59         /* prebuild the SAREA */
  60         sareapage = max(SAREA_MAX, PAGE_SIZE);
  61         i = drm_addmap(dev, 0, sareapage, _DRM_SHM, _DRM_CONTAINS_LOCK, &map);
  62         if (i != 0)
  63                 return i;
  64
  65         atomic_set(&dev->ioctl_count, 0);
  66         atomic_set(&dev->vma_count, 0);
  67         dev->buf_use = 0;
  68         atomic_set(&dev->buf_alloc, 0);
  69
  70         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) {
  71                 i = drm_dma_setup(dev);
  72                 if (i < 0)
  73                         return i;
  74         }
  75
  76         for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
  77                 atomic_set(&dev->counts[i], 0);
  78
  79         drm_ht_create(&dev->magiclist, DRM_MAGIC_HASH_ORDER);
  80         INIT_LIST_HEAD(&dev->magicfree);
  81
  82         INIT_LIST_HEAD(&dev->ctxlist);
  83         INIT_LIST_HEAD(&dev->vmalist);
  84
  85         dev->sigdata.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_async = NULL;
 105         init_waitqueue_head(&dev->buf_readers);
 106         init_waitqueue_head(&dev->buf_writers);
 107
 108         DRM_DEBUG("\n");
 109
 110         /*
 111          * The kernel's context could be created here, but is now created
 112          * in drm_dma_enqueue.  This is more resource-efficient for
 113          * hardware that does not do DMA, but may mean that
 114          * drm_select_queue fails between the time the interrupt is
 115          * initialized and the time the queues are initialized.
 116          */
 117
 118         return 0;
 119 }
 120
 121 /**
 122  * Open file.
 123  *
 124  * \param inode device inode
 125  * \param filp file pointer.
 126  * \return zero on success or a negative number on failure.
 127  *
 128  * Searches the DRM device with the same minor number, calls open_helper(), and
 129  * increments the device open count. If the open count was previous at zero,
 130  * i.e., it's the first that the device is open, then calls setup().
 131  */
 132 int drm_open(struct inode *inode, struct file *filp)
 133 {
 134         drm_device_t *dev = NULL;
 135         int minor = iminor(inode);
 136         int retcode = 0;
 137
 138         if (!((minor >= 0) && (minor < drm_cards_limit)))
 139                 return -ENODEV;
 140
 141         if (!drm_heads[minor])
 142                 return -ENODEV;
 143
 144         if (!(dev = drm_heads[minor]->dev))
 145                 return -ENODEV;
 146
 147         retcode = drm_open_helper(inode, filp, dev);
 148         if (!retcode) {
 149                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
 150                 spin_lock(&dev->count_lock);
 151                 if (!dev->open_count++) {
 152                         spin_unlock(&dev->count_lock);
 153                         retcode = drm_setup(dev);
 154                         goto out;
 155                 }
 156                 spin_unlock(&dev->count_lock);
 157         }
 158
 159  out:
 160         mutex_lock(&dev->struct_mutex);
 161         BUG_ON((dev->dev_mapping != NULL) &&
 162                (dev->dev_mapping != inode->i_mapping));
 163         if (dev->dev_mapping == NULL)
 164                 dev->dev_mapping = inode->i_mapping;
 165         mutex_unlock(&dev->struct_mutex);
 166
 167         return retcode;
 168 }
 169 EXPORT_SYMBOL(drm_open);
 170
 171 /**
 172  * File \c open operation.
 173  *
 174  * \param inode device inode.
 175  * \param filp file pointer.
 176  *
 177  * Puts the dev->fops corresponding to the device minor number into
 178  * \p filp, call the \c open method, and restore the file operations.
 179  */
 180 int drm_stub_open(struct inode *inode, struct file *filp)
 181 {
 182         drm_device_t *dev = NULL;
 183         int minor = iminor(inode);
 184         int err = -ENODEV;
 185         const struct file_operations *old_fops;
 186
 187         DRM_DEBUG("\n");
 188
 189         if (!((minor >= 0) && (minor < drm_cards_limit)))
 190                 return -ENODEV;
 191
 192         if (!drm_heads[minor])
 193                 return -ENODEV;
 194
 195         if (!(dev = drm_heads[minor]->dev))
 196                 return -ENODEV;
 197
 198         old_fops = filp->f_op;
 199         filp->f_op = fops_get(&dev->driver->fops);
 200         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 201                 fops_put(filp->f_op);
 202                 filp->f_op = fops_get(old_fops);
 203         }
 204         fops_put(old_fops);
 205
 206         return err;
 207 }
 208
 209 /**
 210  * Check whether DRI will run on this CPU.
 211  *
 212  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 213  */
 214 static int drm_cpu_valid(void)
 215 {
 216 #if defined(__i386__)
 217         if (boot_cpu_data.x86 == 3)
 218                 return 0;       /* No cmpxchg on a 386 */
 219 #endif
 220 #if defined(__sparc__) && !defined(__sparc_v9__)
 221         return 0;               /* No cmpxchg before v9 sparc. */
 222 #endif
 223         return 1;
 224 }
 225
 226 /**
 227  * Called whenever a process opens /dev/drm.
 228  *
 229  * \param inode device inode.
 230  * \param filp file pointer.
 231  * \param dev device.
 232  * \return zero on success or a negative number on failure.
 233  *
 234  * Creates and initializes a drm_file structure for the file private data in \p
 235  * filp and add it into the double linked list in \p dev.
 236  */
 237 static int drm_open_helper(struct inode *inode, struct file *filp,
 238                            drm_device_t * dev)
 239 {
 240         int minor = iminor(inode);
 241         drm_file_t *priv;
 242         int ret;
 243         int i,j;
 244
 245         if (filp->f_flags & O_EXCL)
 246                 return -EBUSY;  /* No exclusive opens */
 247         if (!drm_cpu_valid())
 248                 return -EINVAL;
 249
 250         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
 251
 252         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 253         if (!priv)
 254                 return -ENOMEM;
 255
 256         memset(priv, 0, sizeof(*priv));
 257         filp->private_data = priv;
 258         priv->uid = current->euid;
 259         priv->pid = current->pid;
 260         priv->minor = minor;
 261         priv->head = drm_heads[minor];
 262         priv->ioctl_count = 0;
 263         /* for compatibility root is always authenticated */
 264         priv->authenticated = capable(CAP_SYS_ADMIN);
 265         priv->lock_count = 0;
 266
 267         INIT_LIST_HEAD(&priv->lhead);
 268         INIT_LIST_HEAD(&priv->user_objects);
 269         INIT_LIST_HEAD(&priv->refd_objects);
 270
 271         for (i=0; i<_DRM_NO_REF_TYPES; ++i) {
 272                 ret = drm_ht_create(&priv->refd_object_hash[i], DRM_FILE_HASH_ORDER);
 273                 if (ret)
 274                         break;
 275         }
 276
 277         if (ret) {
 278                 for(j=0; j<i; ++j) {
 279                         drm_ht_remove(&priv->refd_object_hash[j]);
 280                 }
 281                 goto out_free;
 282         }
 283
 284         if (dev->driver->open) {
 285                 ret = dev->driver->open(dev, priv);
 286                 if (ret < 0)
 287                         goto out_free;
 288         }
 289
 290         mutex_lock(&dev->struct_mutex);
 291         if (list_empty(&dev->filelist))
 292                 priv->master = 1;
 293
 294         list_add(&priv->lhead, &dev->filelist);
 295         mutex_unlock(&dev->struct_mutex);
 296
 297 #ifdef __alpha__
 298         /*
 299          * Default the hose
 300          */
 301         if (!dev->hose) {
 302                 struct pci_dev *pci_dev;
 303                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 304                 if (pci_dev) {
 305                         dev->hose = pci_dev->sysdata;
 306                         pci_dev_put(pci_dev);
 307                 }
 308                 if (!dev->hose) {
 309                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 310                         if (b)
 311                                 dev->hose = b->sysdata;
 312                 }
 313         }
 314 #endif
 315
 316         return 0;
 317       out_free:
 318         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 319         filp->private_data = NULL;
 320         return ret;
 321 }
 322
 323 /** No-op. */
 324 int drm_fasync(int fd, struct file *filp, int on)
 325 {
 326         drm_file_t *priv = filp->private_data;
 327         drm_device_t *dev = priv->head->dev;
 328         int retcode;
 329
 330         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
 331                   (long)old_encode_dev(priv->head->device));
 332         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 333         if (retcode < 0)
 334                 return retcode;
 335         return 0;
 336 }
 337 EXPORT_SYMBOL(drm_fasync);
 338
 339 static void drm_object_release(struct file *filp) {
 340
 341         drm_file_t *priv = filp->private_data;
 342         struct list_head *head;
 343         drm_user_object_t *user_object;
 344         drm_ref_object_t *ref_object;
 345         int i;
 346
 347         /*
 348          * Free leftover ref objects created by me. Note that we cannot use
 349          * list_for_each() here, as the struct_mutex may be temporarily released
 350          * by the remove_() functions, and thus the lists may be altered.
 351          * Also, a drm_remove_ref_object() will not remove it
 352          * from the list unless its refcount is 1.
 353          */
 354
 355         head = &priv->refd_objects;
 356         while (head->next != head) {
 357                 ref_object = list_entry(head->next, drm_ref_object_t, list);
 358                 drm_remove_ref_object(priv, ref_object);
 359                 head = &priv->refd_objects;
 360         }
 361
 362         /*
 363          * Free leftover user objects created by me.
 364          */
 365
 366         head = &priv->user_objects;
 367         while (head->next != head) {
 368                 user_object = list_entry(head->next, drm_user_object_t, list);
 369                 drm_remove_user_object(priv, user_object);
 370                 head = &priv->user_objects;
 371         }
 372
 373         for(i=0; i<_DRM_NO_REF_TYPES; ++i) {
 374                 drm_ht_remove(&priv->refd_object_hash[i]);
 375         }
 376 }
 377
 378 /**
 379  * Release file.
 380  *
 381  * \param inode device inode
 382  * \param filp file pointer.
 383  * \return zero on success or a negative number on failure.
 384  *
 385  * If the hardware lock is held then free it, and take it again for the kernel
 386  * context since it's necessary to reclaim buffers. Unlink the file private
 387  * data from its list and free it. Decreases the open count and if it reaches
 388  * zero calls drm_lastclose().
 389  */
 390 int drm_release(struct inode *inode, struct file *filp)
 391 {
 392         drm_file_t *priv = filp->private_data;
 393         drm_device_t *dev;
 394         int retcode = 0;
 395
 396         lock_kernel();
 397         dev = priv->head->dev;
 398
 399         DRM_DEBUG("open_count = %d\n", dev->open_count);
 400
 401         if (dev->driver->preclose)
 402                 dev->driver->preclose(dev, filp);
 403
 404         /* ========================================================
 405          * Begin inline drm_release
 406          */
 407
 408         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 409                   current->pid, (long)old_encode_dev(priv->head->device),
 410                   dev->open_count);
 411
 412         if (dev->driver->reclaim_buffers_locked && dev->lock.hw_lock) {
 413                 if (drm_i_have_hw_lock(filp)) {
 414                         dev->driver->reclaim_buffers_locked(dev, filp);
 415                 } else {
 416                         unsigned long _end=jiffies + 3*DRM_HZ;
 417                         int locked = 0;
 418
 419                         drm_idlelock_take(&dev->lock);
 420
 421                         /*
 422                          * Wait for a while.
 423                          */
 424
 425                         do{
 426                                 spin_lock(&dev->lock.spinlock);
 427                                 locked = dev->lock.idle_has_lock;
 428                                 spin_unlock(&dev->lock.spinlock);
 429                                 if (locked)
 430                                         break;
 431                                 schedule();
 432                         } while (!time_after_eq(jiffies, _end));
 433
 434                         if (!locked) {
 435                                 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
 436                                           "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
 437                                           "\tI will go on reclaiming the buffers anyway.\n");
 438                         }
 439
 440                         dev->driver->reclaim_buffers_locked(dev, filp);
 441                         drm_idlelock_release(&dev->lock);
 442                 }
 443         }
 444
 445         if (dev->driver->reclaim_buffers_idlelocked && dev->lock.hw_lock) {
 446
 447                 drm_idlelock_take(&dev->lock);
 448                 dev->driver->reclaim_buffers_idlelocked(dev, filp);
 449                 drm_idlelock_release(&dev->lock);
 450
 451         }
 452
 453         if (drm_i_have_hw_lock(filp)) {
 454                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
 455                           filp, _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 456
 457                 drm_lock_free(&dev->lock,
 458                               _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 459         }
 460
 461
 462         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 463             !dev->driver->reclaim_buffers_locked) {
 464                 dev->driver->reclaim_buffers(dev, filp);
 465         }
 466
 467         drm_fasync(-1, filp, 0);
 468
 469         mutex_lock(&dev->ctxlist_mutex);
 470
 471         if (!list_empty(&dev->ctxlist)) {
 472                 drm_ctx_list_t *pos, *n;
 473
 474                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
 475                         if (pos->tag == priv &&
 476                             pos->handle != DRM_KERNEL_CONTEXT) {
 477                                 if (dev->driver->context_dtor)
 478                                         dev->driver->context_dtor(dev,
 479                                                                   pos->handle);
 480
 481                                 drm_ctxbitmap_free(dev, pos->handle);
 482
 483                                 list_del(&pos->head);
 484                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
 485                                 --dev->ctx_count;
 486                         }
 487                 }
 488         }
 489         mutex_unlock(&dev->ctxlist_mutex);
 490
 491         mutex_lock(&dev->struct_mutex);
 492         drm_object_release(filp);
 493         if (priv->remove_auth_on_close == 1) {
 494                 drm_file_t *temp;
 495
 496                 list_for_each_entry(temp, &dev->filelist, lhead)
 497                         temp->authenticated = 0;
 498         }
 499         list_del(&priv->lhead);
 500         mutex_unlock(&dev->struct_mutex);
 501
 502         if (dev->driver->postclose)
 503                 dev->driver->postclose(dev, priv);
 504         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 505
 506         /* ========================================================
 507          * End inline drm_release
 508          */
 509
 510         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 511         spin_lock(&dev->count_lock);
 512         if (!--dev->open_count) {
 513                 if (atomic_read(&dev->ioctl_count) || dev->blocked) {
 514                         DRM_ERROR("Device busy: %d %d\n",
 515                                   atomic_read(&dev->ioctl_count), dev->blocked);
 516                         spin_unlock(&dev->count_lock);
 517                         unlock_kernel();
 518                         return -EBUSY;
 519                 }
 520                 spin_unlock(&dev->count_lock);
 521                 unlock_kernel();
 522                 return drm_lastclose(dev);
 523         }
 524         spin_unlock(&dev->count_lock);
 525
 526         unlock_kernel();
 527
 528         return retcode;
 529 }
 530 EXPORT_SYMBOL(drm_release);
 531
 532 /** No-op. */
 533 /* This is to deal with older X servers that believe 0 means data is
 534  * available which is not the correct return for a poll function.
 535  * This cannot be fixed until the Xserver is fixed. Xserver will need
 536  * to set a newer interface version to avoid breaking older Xservers.
 537  * Without fixing the Xserver you get: "WaitForSomething(): select: errno=22"
 538  * http://freedesktop.org/bugzilla/show_bug.cgi?id=1505 if you try
 539  * to return the correct response.
 540  */
 541 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 542 {
 543         /* return (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM); */
 544         return 0;
 545 }
 546 EXPORT_SYMBOL(drm_poll);
 547