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         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->context_flag = 0;
  89         dev->interrupt_flag = 0;
  90         dev->dma_flag = 0;
  91         dev->last_context = 0;
  92         dev->last_switch = 0;
  93         dev->last_checked = 0;
  94         init_waitqueue_head(&dev->context_wait);
  95         dev->if_version = 0;
  96
  97         dev->ctx_start = 0;
  98         dev->lck_start = 0;
  99
 100         dev->buf_async = NULL;
 101         init_waitqueue_head(&dev->buf_readers);
 102         init_waitqueue_head(&dev->buf_writers);
 103
 104         DRM_DEBUG("\n");
 105
 106         /*
 107          * The kernel's context could be created here, but is now created
 108          * in drm_dma_enqueue.  This is more resource-efficient for
 109          * hardware that does not do DMA, but may mean that
 110          * drm_select_queue fails between the time the interrupt is
 111          * initialized and the time the queues are initialized.
 112          */
 113
 114         return 0;
 115 }
 116
 117 /**
 118  * Open file.
 119  *
 120  * \param inode device inode
 121  * \param filp file pointer.
 122  * \return zero on success or a negative number on failure.
 123  *
 124  * Searches the DRM device with the same minor number, calls open_helper(), and
 125  * increments the device open count. If the open count was previous at zero,
 126  * i.e., it's the first that the device is open, then calls setup().
 127  */
 128 int drm_open(struct inode *inode, struct file *filp)
 129 {
 130         struct drm_device *dev = NULL;
 131         int minor_id = iminor(inode);
 132         struct drm_minor *minor;
 133         int retcode = 0;
 134
 135         minor = idr_find(&drm_minors_idr, minor_id);
 136         if (!minor)
 137                 return -ENODEV;
 138
 139         if (!(dev = minor->dev))
 140                 return -ENODEV;
 141
 142         retcode = drm_open_helper(inode, filp, dev);
 143         if (!retcode) {
 144                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
 145                 spin_lock(&dev->count_lock);
 146                 if (!dev->open_count++) {
 147                         spin_unlock(&dev->count_lock);
 148                         retcode = drm_setup(dev);
 149                         goto out;
 150                 }
 151                 spin_unlock(&dev->count_lock);
 152         }
 153
 154 out:
 155         return retcode;
 156 }
 157 EXPORT_SYMBOL(drm_open);
 158
 159 /**
 160  * File \c open operation.
 161  *
 162  * \param inode device inode.
 163  * \param filp file pointer.
 164  *
 165  * Puts the dev->fops corresponding to the device minor number into
 166  * \p filp, call the \c open method, and restore the file operations.
 167  */
 168 int drm_stub_open(struct inode *inode, struct file *filp)
 169 {
 170         struct drm_device *dev = NULL;
 171         struct drm_minor *minor;
 172         int minor_id = iminor(inode);
 173         int err = -ENODEV;
 174         const struct file_operations *old_fops;
 175
 176         DRM_DEBUG("\n");
 177
 178         minor = idr_find(&drm_minors_idr, minor_id);
 179         if (!minor)
 180                 return -ENODEV;
 181
 182         if (!(dev = minor->dev))
 183                 return -ENODEV;
 184
 185         old_fops = filp->f_op;
 186         filp->f_op = fops_get(&dev->driver->fops);
 187         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 188                 fops_put(filp->f_op);
 189                 filp->f_op = fops_get(old_fops);
 190         }
 191         fops_put(old_fops);
 192
 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         int i, j;
 231
 232         if (filp->f_flags & O_EXCL)
 233                 return -EBUSY;  /* No exclusive opens */
 234         if (!drm_cpu_valid())
 235                 return -EINVAL;
 236
 237         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor_id);
 238
 239         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 240         if (!priv)
 241                 return -ENOMEM;
 242
 243         memset(priv, 0, sizeof(*priv));
 244         filp->private_data = priv;
 245         priv->filp = filp;
 246         priv->uid = current_euid();
 247         priv->pid = current->pid;
 248         priv->minor = idr_find(&drm_minors_idr, minor_id);
 249         priv->ioctl_count = 0;
 250         /* for compatibility root is always authenticated */
 251         priv->authenticated = capable(CAP_SYS_ADMIN);
 252         priv->lock_count = 0;
 253
 254         INIT_LIST_HEAD(&priv->lhead);
 255         INIT_LIST_HEAD(&priv->refd_objects);
 256
 257         for (i = 0; i < _DRM_NO_REF_TYPES; ++i) {
 258                 ret = drm_ht_create(&priv->refd_object_hash[i],
 259                                     DRM_FILE_HASH_ORDER);
 260                 if (ret)
 261                         break;
 262         }
 263
 264         if (ret) {
 265                 for (j = 0; j < i; ++j)
 266                         drm_ht_remove(&priv->refd_object_hash[j]);
 267                 goto out_free;
 268         }
 269
 270         if (dev->driver->driver_features & DRIVER_GEM)
 271                 drm_gem_open(dev, priv);
 272
 273         if (dev->driver->open) {
 274                 ret = dev->driver->open(dev, priv);
 275                 if (ret < 0)
 276                         goto out_free;
 277         }
 278
 279         mutex_lock(&dev->struct_mutex);
 280         if (list_empty(&dev->filelist))
 281                 priv->master = 1;
 282
 283         list_add(&priv->lhead, &dev->filelist);
 284         mutex_unlock(&dev->struct_mutex);
 285
 286 #ifdef __alpha__
 287         /*
 288          * Default the hose
 289          */
 290         if (!dev->hose) {
 291                 struct pci_dev *pci_dev;
 292                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 293                 if (pci_dev) {
 294                         dev->hose = pci_dev->sysdata;
 295                         pci_dev_put(pci_dev);
 296                 }
 297                 if (!dev->hose) {
 298                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 299                         if (b)
 300                                 dev->hose = b->sysdata;
 301                 }
 302         }
 303 #endif
 304
 305         return 0;
 306       out_free:
 307         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 308         filp->private_data = NULL;
 309         return ret;
 310 }
 311
 312 /** No-op. */
 313 int drm_fasync(int fd, struct file *filp, int on)
 314 {
 315         struct drm_file *priv = filp->private_data;
 316         struct drm_device *dev = priv->minor->dev;
 317         int retcode;
 318
 319         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
 320                   (long)old_encode_dev(priv->minor->device));
 321         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 322         if (retcode < 0)
 323                 return retcode;
 324         return 0;
 325 }
 326 EXPORT_SYMBOL(drm_fasync);
 327
 328 /**
 329  * Release file.
 330  *
 331  * \param inode device inode
 332  * \param file_priv DRM file private.
 333  * \return zero on success or a negative number on failure.
 334  *
 335  * If the hardware lock is held then free it, and take it again for the kernel
 336  * context since it's necessary to reclaim buffers. Unlink the file private
 337  * data from its list and free it. Decreases the open count and if it reaches
 338  * zero calls drm_lastclose().
 339  */
 340 int drm_release(struct inode *inode, struct file *filp)
 341 {
 342         struct drm_file *file_priv = filp->private_data;
 343         struct drm_device *dev = file_priv->minor->dev;
 344         int retcode = 0;
 345
 346         lock_kernel();
 347
 348         DRM_DEBUG("open_count = %d\n", dev->open_count);
 349
 350         if (dev->driver->preclose)
 351                 dev->driver->preclose(dev, file_priv);
 352
 353         /* ========================================================
 354          * Begin inline drm_release
 355          */
 356
 357         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 358                   current->pid, (long)old_encode_dev(file_priv->minor->device),
 359                   dev->open_count);
 360
 361         if (dev->driver->reclaim_buffers_locked && dev->lock.hw_lock) {
 362                 if (drm_i_have_hw_lock(dev, file_priv)) {
 363                         dev->driver->reclaim_buffers_locked(dev, file_priv);
 364                 } else {
 365                         unsigned long _end=jiffies + 3*DRM_HZ;
 366                         int locked = 0;
 367
 368                         drm_idlelock_take(&dev->lock);
 369
 370                         /*
 371                          * Wait for a while.
 372                          */
 373
 374                         do{
 375                                 spin_lock_bh(&dev->lock.spinlock);
 376                                 locked = dev->lock.idle_has_lock;
 377                                 spin_unlock_bh(&dev->lock.spinlock);
 378                                 if (locked)
 379                                         break;
 380                                 schedule();
 381                         } while (!time_after_eq(jiffies, _end));
 382
 383                         if (!locked) {
 384                                 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
 385                                           "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
 386                                           "\tI will go on reclaiming the buffers anyway.\n");
 387                         }
 388
 389                         dev->driver->reclaim_buffers_locked(dev, file_priv);
 390                         drm_idlelock_release(&dev->lock);
 391                 }
 392         }
 393
 394         if (dev->driver->reclaim_buffers_idlelocked && dev->lock.hw_lock) {
 395
 396                 drm_idlelock_take(&dev->lock);
 397                 dev->driver->reclaim_buffers_idlelocked(dev, file_priv);
 398                 drm_idlelock_release(&dev->lock);
 399
 400         }
 401
 402         if (drm_i_have_hw_lock(dev, file_priv)) {
 403                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
 404                           filp, _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 405
 406                 drm_lock_free(&dev->lock,
 407                               _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 408         }
 409
 410
 411         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 412             !dev->driver->reclaim_buffers_locked) {
 413                 dev->driver->reclaim_buffers(dev, file_priv);
 414         }
 415
 416         if (dev->driver->driver_features & DRIVER_GEM)
 417                 drm_gem_release(dev, file_priv);
 418
 419         drm_fasync(-1, filp, 0);
 420
 421         mutex_lock(&dev->ctxlist_mutex);
 422
 423         if (!list_empty(&dev->ctxlist)) {
 424                 struct drm_ctx_list *pos, *n;
 425
 426                 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) {
 427                         if (pos->tag == file_priv &&
 428                             pos->handle != DRM_KERNEL_CONTEXT) {
 429                                 if (dev->driver->context_dtor)
 430                                         dev->driver->context_dtor(dev,
 431                                                                   pos->handle);
 432
 433                                 drm_ctxbitmap_free(dev, pos->handle);
 434
 435                                 list_del(&pos->head);
 436                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
 437                                 --dev->ctx_count;
 438                         }
 439                 }
 440         }
 441         mutex_unlock(&dev->ctxlist_mutex);
 442
 443         mutex_lock(&dev->struct_mutex);
 444         if (file_priv->remove_auth_on_close == 1) {
 445                 struct drm_file *temp;
 446
 447                 list_for_each_entry(temp, &dev->filelist, lhead)
 448                         temp->authenticated = 0;
 449         }
 450         list_del(&file_priv->lhead);
 451         mutex_unlock(&dev->struct_mutex);
 452
 453         if (dev->driver->postclose)
 454                 dev->driver->postclose(dev, file_priv);
 455         drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES);
 456
 457         /* ========================================================
 458          * End inline drm_release
 459          */
 460
 461         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 462         spin_lock(&dev->count_lock);
 463         if (!--dev->open_count) {
 464                 if (atomic_read(&dev->ioctl_count) || dev->blocked) {
 465                         DRM_ERROR("Device busy: %d %d\n",
 466                                   atomic_read(&dev->ioctl_count), dev->blocked);
 467                         spin_unlock(&dev->count_lock);
 468                         unlock_kernel();
 469                         return -EBUSY;
 470                 }
 471                 spin_unlock(&dev->count_lock);
 472                 unlock_kernel();
 473                 return drm_lastclose(dev);
 474         }
 475         spin_unlock(&dev->count_lock);
 476
 477         unlock_kernel();
 478
 479         return retcode;
 480 }
 481 EXPORT_SYMBOL(drm_release);
 482
 483 /** No-op. */
 484 /* This is to deal with older X servers that believe 0 means data is
 485  * available which is not the correct return for a poll function.
 486  * This cannot be fixed until the Xserver is fixed. Xserver will need
 487  * to set a newer interface version to avoid breaking older Xservers.
 488  * Without fixing the Xserver you get: "WaitForSomething(): select: errno=22"
 489  * http://freedesktop.org/bugzilla/show_bug.cgi?id=1505 if you try
 490  * to return the correct response.
 491  */
 492 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 493 {
 494         /* return (POLLIN | POLLOUT | POLLRDNORM | POLLWRNORM); */
 495         return 0;
 496 }
 497 EXPORT_SYMBOL(drm_poll);