drivers/char/drm/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         u32 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_t(unsigned, 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->ctxlist = drm_alloc(sizeof(*dev->ctxlist), DRM_MEM_CTXLIST);
  83         if (dev->ctxlist == NULL)
  84                 return -ENOMEM;
  85         memset(dev->ctxlist, 0, sizeof(*dev->ctxlist));
  86         INIT_LIST_HEAD(&dev->ctxlist->head);
  87
  88         dev->vmalist = NULL;
  89         dev->sigdata.lock = NULL;
  90         init_waitqueue_head(&dev->lock.lock_queue);
  91         dev->queue_count = 0;
  92         dev->queue_reserved = 0;
  93         dev->queue_slots = 0;
  94         dev->queuelist = NULL;
  95         dev->irq_enabled = 0;
  96         dev->context_flag = 0;
  97         dev->interrupt_flag = 0;
  98         dev->dma_flag = 0;
  99         dev->last_context = 0;
 100         dev->last_switch = 0;
 101         dev->last_checked = 0;
 102         init_waitqueue_head(&dev->context_wait);
 103         dev->if_version = 0;
 104
 105         dev->ctx_start = 0;
 106         dev->lck_start = 0;
 107
 108         dev->buf_async = NULL;
 109         init_waitqueue_head(&dev->buf_readers);
 110         init_waitqueue_head(&dev->buf_writers);
 111
 112         DRM_DEBUG("\n");
 113
 114         /*
 115          * The kernel's context could be created here, but is now created
 116          * in drm_dma_enqueue.  This is more resource-efficient for
 117          * hardware that does not do DMA, but may mean that
 118          * drm_select_queue fails between the time the interrupt is
 119          * initialized and the time the queues are initialized.
 120          */
 121
 122         return 0;
 123 }
 124
 125 /**
 126  * Open file.
 127  *
 128  * \param inode device inode
 129  * \param filp file pointer.
 130  * \return zero on success or a negative number on failure.
 131  *
 132  * Searches the DRM device with the same minor number, calls open_helper(), and
 133  * increments the device open count. If the open count was previous at zero,
 134  * i.e., it's the first that the device is open, then calls setup().
 135  */
 136 int drm_open(struct inode *inode, struct file *filp)
 137 {
 138         drm_device_t *dev = NULL;
 139         int minor = iminor(inode);
 140         int retcode = 0;
 141
 142         if (!((minor >= 0) && (minor < drm_cards_limit)))
 143                 return -ENODEV;
 144
 145         if (!drm_heads[minor])
 146                 return -ENODEV;
 147
 148         if (!(dev = drm_heads[minor]->dev))
 149                 return -ENODEV;
 150
 151         retcode = drm_open_helper(inode, filp, dev);
 152         if (!retcode) {
 153                 atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
 154                 spin_lock(&dev->count_lock);
 155                 if (!dev->open_count++) {
 156                         spin_unlock(&dev->count_lock);
 157                         return drm_setup(dev);
 158                 }
 159                 spin_unlock(&dev->count_lock);
 160         }
 161
 162         return retcode;
 163 }
 164 EXPORT_SYMBOL(drm_open);
 165
 166 /**
 167  * File \c open operation.
 168  *
 169  * \param inode device inode.
 170  * \param filp file pointer.
 171  *
 172  * Puts the dev->fops corresponding to the device minor number into
 173  * \p filp, call the \c open method, and restore the file operations.
 174  */
 175 int drm_stub_open(struct inode *inode, struct file *filp)
 176 {
 177         drm_device_t *dev = NULL;
 178         int minor = iminor(inode);
 179         int err = -ENODEV;
 180         const struct file_operations *old_fops;
 181
 182         DRM_DEBUG("\n");
 183
 184         if (!((minor >= 0) && (minor < drm_cards_limit)))
 185                 return -ENODEV;
 186
 187         if (!drm_heads[minor])
 188                 return -ENODEV;
 189
 190         if (!(dev = drm_heads[minor]->dev))
 191                 return -ENODEV;
 192
 193         old_fops = filp->f_op;
 194         filp->f_op = fops_get(&dev->driver->fops);
 195         if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) {
 196                 fops_put(filp->f_op);
 197                 filp->f_op = fops_get(old_fops);
 198         }
 199         fops_put(old_fops);
 200
 201         return err;
 202 }
 203
 204 /**
 205  * Check whether DRI will run on this CPU.
 206  *
 207  * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 208  */
 209 static int drm_cpu_valid(void)
 210 {
 211 #if defined(__i386__)
 212         if (boot_cpu_data.x86 == 3)
 213                 return 0;       /* No cmpxchg on a 386 */
 214 #endif
 215 #if defined(__sparc__) && !defined(__sparc_v9__)
 216         return 0;               /* No cmpxchg before v9 sparc. */
 217 #endif
 218         return 1;
 219 }
 220
 221 /**
 222  * Called whenever a process opens /dev/drm.
 223  *
 224  * \param inode device inode.
 225  * \param filp file pointer.
 226  * \param dev device.
 227  * \return zero on success or a negative number on failure.
 228  *
 229  * Creates and initializes a drm_file structure for the file private data in \p
 230  * filp and add it into the double linked list in \p dev.
 231  */
 232 static int drm_open_helper(struct inode *inode, struct file *filp,
 233                            drm_device_t * dev)
 234 {
 235         int minor = iminor(inode);
 236         drm_file_t *priv;
 237         int ret;
 238
 239         if (filp->f_flags & O_EXCL)
 240                 return -EBUSY;  /* No exclusive opens */
 241         if (!drm_cpu_valid())
 242                 return -EINVAL;
 243
 244         DRM_DEBUG("pid = %d, minor = %d\n", current->pid, minor);
 245
 246         priv = drm_alloc(sizeof(*priv), DRM_MEM_FILES);
 247         if (!priv)
 248                 return -ENOMEM;
 249
 250         memset(priv, 0, sizeof(*priv));
 251         filp->private_data = priv;
 252         priv->uid = current->euid;
 253         priv->pid = current->pid;
 254         priv->minor = minor;
 255         priv->head = drm_heads[minor];
 256         priv->ioctl_count = 0;
 257         /* for compatibility root is always authenticated */
 258         priv->authenticated = capable(CAP_SYS_ADMIN);
 259         priv->lock_count = 0;
 260
 261         if (dev->driver->open) {
 262                 ret = dev->driver->open(dev, priv);
 263                 if (ret < 0)
 264                         goto out_free;
 265         }
 266
 267         mutex_lock(&dev->struct_mutex);
 268         if (!dev->file_last) {
 269                 priv->next = NULL;
 270                 priv->prev = NULL;
 271                 dev->file_first = priv;
 272                 dev->file_last = priv;
 273                 /* first opener automatically becomes master */
 274                 priv->master = 1;
 275         } else {
 276                 priv->next = NULL;
 277                 priv->prev = dev->file_last;
 278                 dev->file_last->next = priv;
 279                 dev->file_last = priv;
 280         }
 281         mutex_unlock(&dev->struct_mutex);
 282
 283 #ifdef __alpha__
 284         /*
 285          * Default the hose
 286          */
 287         if (!dev->hose) {
 288                 struct pci_dev *pci_dev;
 289                 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 290                 if (pci_dev) {
 291                         dev->hose = pci_dev->sysdata;
 292                         pci_dev_put(pci_dev);
 293                 }
 294                 if (!dev->hose) {
 295                         struct pci_bus *b = pci_bus_b(pci_root_buses.next);
 296                         if (b)
 297                                 dev->hose = b->sysdata;
 298                 }
 299         }
 300 #endif
 301
 302         return 0;
 303       out_free:
 304         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 305         filp->private_data = NULL;
 306         return ret;
 307 }
 308
 309 /** No-op. */
 310 int drm_fasync(int fd, struct file *filp, int on)
 311 {
 312         drm_file_t *priv = filp->private_data;
 313         drm_device_t *dev = priv->head->dev;
 314         int retcode;
 315
 316         DRM_DEBUG("fd = %d, device = 0x%lx\n", fd,
 317                   (long)old_encode_dev(priv->head->device));
 318         retcode = fasync_helper(fd, filp, on, &dev->buf_async);
 319         if (retcode < 0)
 320                 return retcode;
 321         return 0;
 322 }
 323 EXPORT_SYMBOL(drm_fasync);
 324
 325 /**
 326  * Release file.
 327  *
 328  * \param inode device inode
 329  * \param filp file pointer.
 330  * \return zero on success or a negative number on failure.
 331  *
 332  * If the hardware lock is held then free it, and take it again for the kernel
 333  * context since it's necessary to reclaim buffers. Unlink the file private
 334  * data from its list and free it. Decreases the open count and if it reaches
 335  * zero calls drm_lastclose().
 336  */
 337 int drm_release(struct inode *inode, struct file *filp)
 338 {
 339         drm_file_t *priv = filp->private_data;
 340         drm_device_t *dev;
 341         int retcode = 0;
 342
 343         lock_kernel();
 344         dev = priv->head->dev;
 345
 346         DRM_DEBUG("open_count = %d\n", dev->open_count);
 347
 348         if (dev->driver->preclose)
 349                 dev->driver->preclose(dev, filp);
 350
 351         /* ========================================================
 352          * Begin inline drm_release
 353          */
 354
 355         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 356                   current->pid, (long)old_encode_dev(priv->head->device),
 357                   dev->open_count);
 358
 359         if (dev->driver->reclaim_buffers_locked && dev->lock.hw_lock) {
 360                 if (drm_i_have_hw_lock(filp)) {
 361                         dev->driver->reclaim_buffers_locked(dev, filp);
 362                 } else {
 363                         unsigned long _end=jiffies + 3*DRM_HZ;
 364                         int locked = 0;
 365
 366                         drm_idlelock_take(&dev->lock);
 367
 368                         /*
 369                          * Wait for a while.
 370                          */
 371
 372                         do{
 373                                 spin_lock(&dev->lock.spinlock);
 374                                 locked = dev->lock.idle_has_lock;
 375                                 spin_unlock(&dev->lock.spinlock);
 376                                 if (locked)
 377                                         break;
 378                                 schedule();
 379                         } while (!time_after_eq(jiffies, _end));
 380
 381                         if (!locked) {
 382                                 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n"
 383                                           "\tdriver to use reclaim_buffers_idlelocked() instead.\n"
 384                                           "\tI will go on reclaiming the buffers anyway.\n");
 385                         }
 386
 387                         dev->driver->reclaim_buffers_locked(dev, filp);
 388                         drm_idlelock_release(&dev->lock);
 389                 }
 390         }
 391
 392         if (dev->driver->reclaim_buffers_idlelocked && dev->lock.hw_lock) {
 393
 394                 drm_idlelock_take(&dev->lock);
 395                 dev->driver->reclaim_buffers_idlelocked(dev, filp);
 396                 drm_idlelock_release(&dev->lock);
 397
 398         }
 399
 400         if (drm_i_have_hw_lock(filp)) {
 401                 DRM_DEBUG("File %p released, freeing lock for context %d\n",
 402                           filp, _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 403
 404                 drm_lock_free(&dev->lock,
 405                               _DRM_LOCKING_CONTEXT(dev->lock.hw_lock->lock));
 406         }
 407
 408
 409         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 410             !dev->driver->reclaim_buffers_locked) {
 411                 dev->driver->reclaim_buffers(dev, filp);
 412         }
 413
 414         drm_fasync(-1, filp, 0);
 415
 416         mutex_lock(&dev->ctxlist_mutex);
 417         if (dev->ctxlist && (!list_empty(&dev->ctxlist->head))) {
 418                 drm_ctx_list_t *pos, *n;
 419
 420                 list_for_each_entry_safe(pos, n, &dev->ctxlist->head, head) {
 421                         if (pos->tag == priv &&
 422                             pos->handle != DRM_KERNEL_CONTEXT) {
 423                                 if (dev->driver->context_dtor)
 424                                         dev->driver->context_dtor(dev,
 425                                                                   pos->handle);
 426
 427                                 drm_ctxbitmap_free(dev, pos->handle);
 428
 429                                 list_del(&pos->head);
 430                                 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST);
 431                                 --dev->ctx_count;
 432                         }
 433                 }
 434         }
 435         mutex_unlock(&dev->ctxlist_mutex);
 436
 437         mutex_lock(&dev->struct_mutex);
 438         if (priv->remove_auth_on_close == 1) {
 439                 drm_file_t *temp = dev->file_first;
 440                 while (temp) {
 441                         temp->authenticated = 0;
 442                         temp = temp->next;
 443                 }
 444         }
 445         if (priv->prev) {
 446                 priv->prev->next = priv->next;
 447         } else {
 448                 dev->file_first = priv->next;
 449         }
 450         if (priv->next) {
 451                 priv->next->prev = priv->prev;
 452         } else {
 453                 dev->file_last = priv->prev;
 454         }
 455         mutex_unlock(&dev->struct_mutex);
 456
 457         if (dev->driver->postclose)
 458                 dev->driver->postclose(dev, priv);
 459         drm_free(priv, sizeof(*priv), DRM_MEM_FILES);
 460
 461         /* ========================================================
 462          * End inline drm_release
 463          */
 464
 465         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 466         spin_lock(&dev->count_lock);
 467         if (!--dev->open_count) {
 468                 if (atomic_read(&dev->ioctl_count) || dev->blocked) {
 469                         DRM_ERROR("Device busy: %d %d\n",
 470                                   atomic_read(&dev->ioctl_count), dev->blocked);
 471                         spin_unlock(&dev->count_lock);
 472                         unlock_kernel();
 473                         return -EBUSY;
 474                 }
 475                 spin_unlock(&dev->count_lock);
 476                 unlock_kernel();
 477                 return drm_lastclose(dev);
 478         }
 479         spin_unlock(&dev->count_lock);
 480
 481         unlock_kernel();
 482
 483         return retcode;
 484 }
 485 EXPORT_SYMBOL(drm_release);
 486
 487 /** No-op. */
 488 unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait)
 489 {
 490         return 0;
 491 }
 492 EXPORT_SYMBOL(drm_poll);