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
  58         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && !drm_core_check_feature(dev, DRIVER_MODESET)) {
  59                 dev->buf_use = 0;
  60                 atomic_set(&dev->buf_alloc, 0);
  61
  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         BUG_ON((dev->dev_mapping != NULL) &&
 145                (dev->dev_mapping != inode->i_mapping));
 146         if (dev->dev_mapping == NULL)
 147                 dev->dev_mapping = inode->i_mapping;
 148         mutex_unlock(&dev->struct_mutex);
 149
 150         return retcode;
 151 }
 152 EXPORT_SYMBOL(drm_open);
 153
 154 /**
 155  * File \c open operation.
 156  *
 157  * \param inode device inode.
 158  * \param filp file pointer.
 159  *
 160  * Puts the dev->fops corresponding to the device minor number into
 161  * \p filp, call the \c open method, and restore the file operations.
 162  */
 163 int drm_stub_open(struct inode *inode, struct file *filp)
 164 {
 165         struct drm_device *dev = NULL;
 166         struct drm_minor *minor;
 167         int minor_id = iminor(inode);
 168         int err = -ENODEV;
 169         const struct file_operations *old_fops;
 170
 171         DRM_DEBUG("\n");
 172
 173         minor = idr_find(&drm_minors_idr, minor_id);
 174         if (!minor)
 175                 return -ENODEV;
 176
 177         if (!(dev = minor->dev))
 178                 return -ENODEV;
 179
 180         old_fops = filp->f_op;
 181         filp->f_op = fops_get(&dev->driver->fops);
 182         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 183                 fops_put(filp->f_op);
 184                 filp->f_op = fops_get(old_fops);
 185         }
 186         fops_put(old_fops);
 187
 188         return err;
 189 }
 190
 191 /**
 192  * Check whether DRI will run on this CPU.
 193  *
 194  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 195  */
 196 static int drm_cpu_valid(void)
 197 {
 198 #if defined(__i386__)
 199         if (boot_cpu_data.x86 == 3)
 200                 return 0;       /* No cmpxchg on a 386 */
 201 #endif
 202 #if defined(__sparc__) && !defined(__sparc_v9__)
 203         return 0;               /* No cmpxchg before v9 sparc. */
 204 #endif
 205         return 1;
 206 }
 207
 208 /**
 209  * Called whenever a process opens /dev/drm.
 210  *
 211  * \param inode device inode.
 212  * \param filp file pointer.
 213  * \param dev device.
 214  * \return zero on success or a negative number on failure.
 215  *
 216  * Creates and initializes a drm_file structure for the file private data in \p
 217  * filp and add it into the double linked list in \p dev.
 218  */
 219 static int drm_open_helper(struct inode *inode, struct file *filp,
 220                            struct drm_device * dev)
 221 {
 222         int minor_id = iminor(inode);
 223         struct drm_file *priv;
 224         int ret;
 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->fbs);
 250
 251         if (dev->driver->driver_features & DRIVER_GEM)
 252                 drm_gem_open(dev, priv);
 253
 254         if (dev->driver->open) {
 255                 ret = dev->driver->open(dev, priv);
 256                 if (ret < 0)
 257                         goto out_free;
 258         }
 259
 260
 261         /* if there is no current master make this fd it */
 262         mutex_lock(&dev->struct_mutex);
 263         if (!priv->minor->master) {
 264                 /* create a new master */
 265                 priv->minor->master = drm_master_create(priv->minor);
 266                 if (!priv->minor->master) {
 267                         ret = -ENOMEM;
 268                         goto out_free;
 269                 }
 270
 271                 priv->is_master = 1;
 272                 /* take another reference for the copy in the local file priv */
 273                 priv->master = drm_master_get(priv->minor->master);
 274
 275                 priv->authenticated = 1;
 276
 277                 mutex_unlock(&dev->struct_mutex);
 278                 if (dev->driver->master_create) {
 279                         ret = dev->driver->master_create(dev, priv->master);
 280                         if (ret) {
 281                                 mutex_lock(&dev->struct_mutex);
 282                                 /* drop both references if this fails */
 283                                 drm_master_put(&priv->minor->master);
 284                                 drm_master_put(&priv->master);
 285                                 mutex_unlock(&dev->struct_mutex);
 286                                 goto out_free;
 287                         }
 288                 }
 289         } else {
 290                 /* get a reference to the master */
 291                 priv->master = drm_master_get(priv->minor->master);
 292                 mutex_unlock(&dev->struct_mutex);
 293         }
 294
 295         mutex_lock(&dev->struct_mutex);
 296         list_add(&priv->lhead, &dev->filelist);
 297         mutex_unlock(&dev->struct_mutex);
 298
 299 #ifdef __alpha__
 300         /*
 301          * Default the hose
 302          */
 303         if (!dev->hose) {
 304                 struct pci_dev *pci_dev;
 305                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 306                 if (pci_dev) {
 307                         dev->hose = pci_dev->sysdata;
 308                         pci_dev_put(pci_dev);
 309                 }
 310                 if (!dev->hose) {
 311                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 312                         if (b)
 313                                 dev->hose = b->sysdata;
 314                 }
 315         }
 316 #endif
 317
 318         return 0;
 319       out_free:
 320         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 321         filp->private_data = NULL;
 322         return ret;
 323 }
 324
 325 /** No-op. */
 326 int drm_fasync(int fd, struct file *filp, int on)
 327 {
 328         struct drm_file *priv = filp->private_data;
 329         struct drm_device *dev = priv->minor->dev;
 330         int retcode;
 331
 332         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
 333                   (long)old_encode_dev(priv->minor->device));
 334         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 335         if (retcode < 0)
 336                 return retcode;
 337         return 0;
 338 }
 339 EXPORT_SYMBOL(drm_fasync);
 340
 341 /**
 342  * Release file.
 343  *
 344  * \param inode device inode
 345  * \param file_priv DRM file private.
 346  * \return zero on success or a negative number on failure.
 347  *
 348  * If the hardware lock is held then free it, and take it again for the kernel
 349  * context since it's necessary to reclaim buffers. Unlink the file private
 350  * data from its list and free it. Decreases the open count and if it reaches
 351  * zero calls drm_lastclose().
 352  */
 353 int drm_release(struct inode *inode, struct file *filp)
 354 {
 355         struct drm_file *file_priv = filp->private_data;
 356         struct drm_device *dev = file_priv->minor->dev;
 357         int retcode = 0;
 358
 359         lock_kernel();
 360
 361         DRM_DEBUG("open_count = %d\n", dev->open_count);
 362
 363         if (dev->driver->preclose)
 364                 dev->driver->preclose(dev, file_priv);
 365
 366         /* ========================================================
 367          * Begin inline drm_release
 368          */
 369
 370         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 371                   current->pid, (long)old_encode_dev(file_priv->minor->device),
 372                   dev->open_count);
 373
 374         /* if the master has gone away we can't do anything with the lock */
 375         if (file_priv->minor->master) {
 376                 if (dev->driver->reclaim_buffers_locked && file_priv->master->lock.hw_lock) {
 377                         if (drm_i_have_hw_lock(dev, file_priv)) {
 378                                 dev->driver->reclaim_buffers_locked(dev, file_priv);
 379                         } else {
 380                                 unsigned long _end=jiffies + 3*DRM_HZ;
 381                                 int locked = 0;
 382
 383                                 drm_idlelock_take(&file_priv->master->lock);
 384
 385                                 /*
 386                                  * Wait for a while.
 387                                  */
 388
 389                                 do{
 390                                         spin_lock_bh(&file_priv->master->lock.spinlock);
 391                                         locked = file_priv->master->lock.idle_has_lock;
 392                                         spin_unlock_bh(&file_priv->master->lock.spinlock);
 393                                         if (locked)
 394                                                 break;
 395                                         schedule();
 396                                 } while (!time_after_eq(jiffies, _end));
 397
 398                                 if (!locked) {
 399                                         DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
 400                                                   "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
 401                                                   "\tI will go on reclaiming the buffers anyway.\n");
 402                                 }
 403
 404                                 dev->driver->reclaim_buffers_locked(dev, file_priv);
 405                                 drm_idlelock_release(&file_priv->master->lock);
 406                         }
 407                 }
 408
 409                 if (dev->driver->reclaim_buffers_idlelocked && file_priv->master->lock.hw_lock) {
 410
 411                         drm_idlelock_take(&file_priv->master->lock);
 412                         dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
 413                         drm_idlelock_release(&file_priv->master->lock);
 414
 415                 }
 416
 417
 418                 if (drm_i_have_hw_lock(dev, file_priv)) {
 419                         DRM_DEBUG("File %p released, freeing lock for context %d\n",
 420                                   filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
 421
 422                         drm_lock_free(&file_priv->master->lock,
 423                                       _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock));
 424                 }
 425
 426
 427                 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 428                     !dev->driver->reclaim_buffers_locked) {
 429                         dev->driver->reclaim_buffers(dev, file_priv);
 430                 }
 431         }
 432
 433         if (dev->driver->driver_features & DRIVER_GEM)
 434                 drm_gem_release(dev, file_priv);
 435
 436         drm_fasync(-1, filp, 0);
 437
 438         mutex_lock(&dev->ctxlist_mutex);
 439
 440         if (!list_empty(&dev->ctxlist)) {
 441                 struct drm_ctx_list *pos, *n;
 442
 443                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
 444                         if (pos->tag == file_priv &&
 445                             pos->handle != DRM_KERNEL_CONTEXT) {
 446                                 if (dev->driver->context_dtor)
 447                                         dev->driver->context_dtor(dev,
 448                                                                   pos->handle);
 449
 450                                 drm_ctxbitmap_free(dev, pos->handle);
 451
 452                                 list_del(&pos->head);
 453                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
 454                                 --dev->ctx_count;
 455                         }
 456                 }
 457         }
 458         mutex_unlock(&dev->ctxlist_mutex);
 459
 460         if (drm_core_check_feature(dev, DRIVER_MODESET))
 461                 drm_fb_release(filp);
 462
 463         mutex_lock(&dev->struct_mutex);
 464
 465         if (file_priv->is_master) {
 466                 struct drm_file *temp;
 467                 list_for_each_entry(temp, &dev->filelist, lhead) {
 468                         if ((temp->master == file_priv->master) &&
 469                             (temp != file_priv))
 470                                 temp->authenticated = 0;
 471                 }
 472
 473                 if (file_priv->minor->master == file_priv->master) {
 474                         /* drop the reference held my the minor */
 475                         drm_master_put(&file_priv->minor->master);
 476                 }
 477         }
 478
 479         /* drop the reference held my the file priv */
 480         drm_master_put(&file_priv->master);
 481         file_priv->is_master = 0;
 482
 483         list_del(&file_priv->lhead);
 484         mutex_unlock(&dev->struct_mutex);
 485
 486         if (dev->driver->postclose)
 487                 dev->driver->postclose(dev, file_priv);
 488         drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES);
 489
 490         /* ========================================================
 491          * End inline drm_release
 492          */
 493
 494         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 495         spin_lock(&dev->count_lock);
 496         if (!--dev->open_count) {
 497                 if (atomic_read(&dev->ioctl_count)) {
 498                         DRM_ERROR("Device busy: %d\n",
 499                                   atomic_read(&dev->ioctl_count));
 500                         spin_unlock(&dev->count_lock);
 501                         unlock_kernel();
 502                         return -EBUSY;
 503                 }
 504                 spin_unlock(&dev->count_lock);
 505                 unlock_kernel();
 506                 return drm_lastclose(dev);
 507         }
 508         spin_unlock(&dev->count_lock);
 509
 510         unlock_kernel();
 511
 512         return retcode;
 513 }
 514 EXPORT_SYMBOL(drm_release);
 515
 516 /** No-op. */
 517 /* This is to deal with older X servers that believe 0 means data is
 518  * available which is not the correct return for a poll function.
 519  * This cannot be fixed until the Xserver is fixed. Xserver will need
 520  * to set a newer interface version to avoid breaking older Xservers.
 521  * Without fixing the Xserver you get: "WaitForSomething(): select: errno=22"
 522  * http://freedesktop.org/bugzilla/show_bug.cgi?id=1505 if you try
 523  * to return the correct response.
 524  */
 525 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 526 {
 527         /* return (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM); */
 528         return 0;
 529 }
 530 EXPORT_SYMBOL(drm_poll);