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