sys/dev/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 <sys/devfs.h>
  38 #include <sys/file.h>
  39
  40 #include <drm/drmP.h>
  41 #include <linux/module.h>
  42
  43 static int drm_open_helper(struct cdev *kdev, int flags, int fmt, DRM_STRUCTPROC *p,
  44                     struct drm_device *dev, struct file *fp);
  45
  46 static int drm_setup(struct drm_device *dev)
  47 {
  48         drm_local_map_t *map;
  49         int i;
  50         int ret;
  51
  52         /* prebuild the SAREA */
  53         i = drm_addmap(dev, 0, SAREA_MAX, _DRM_SHM,
  54             _DRM_CONTAINS_LOCK, &map);
  55         if (i != 0)
  56                 return i;
  57
  58         if (dev->driver->firstopen) {
  59                 ret = dev->driver->firstopen(dev);
  60                 if (ret != 0)
  61                         return ret;
  62         }
  63
  64         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
  65             !drm_core_check_feature(dev, DRIVER_MODESET)) {
  66                 dev->buf_use = 0;
  67                 atomic_set(&dev->buf_alloc, 0);
  68
  69                 i = drm_dma_setup(dev);
  70                 if (i != 0)
  71                         return i;
  72         }
  73
  74         for (i = 0; i < ARRAY_SIZE(dev->counts); i++)
  75                 atomic_set(&dev->counts[i], 0);
  76
  77         dev->sigdata.lock = NULL;
  78
  79         dev->context_flag = 0;
  80         dev->interrupt_flag = 0;
  81         dev->dma_flag = 0;
  82         dev->last_context = 0;
  83         dev->last_switch = 0;
  84         dev->last_checked = 0;
  85         init_waitqueue_head(&dev->context_wait);
  86         dev->if_version = 0;
  87
  88         dev->ctx_start = 0;
  89         dev->lck_start = 0;
  90
  91         dev->buf_async = NULL;
  92         init_waitqueue_head(&dev->buf_readers);
  93         init_waitqueue_head(&dev->buf_writers);
  94
  95         DRM_DEBUG("\n");
  96
  97         /*
  98          * The kernel's context could be created here, but is now created
  99          * in drm_dma_enqueue.  This is more resource-efficient for
 100          * hardware that does not do DMA, but may mean that
 101          * drm_select_queue fails between the time the interrupt is
 102          * initialized and the time the queues are initialized.
 103          */
 104
 105         return 0;
 106 }
 107
 108 #define DRIVER_SOFTC(unit) \
 109         ((struct drm_device *)devclass_get_softc(drm_devclass, unit))
 110
 111 /**
 112  * Open file.
 113  *
 114  * \param inode device inode
 115  * \param filp file pointer.
 116  * \return zero on success or a negative number on failure.
 117  *
 118  * Searches the DRM device with the same minor number, calls open_helper(), and
 119  * increments the device open count. If the open count was previous at zero,
 120  * i.e., it's the first that the device is open, then calls setup().
 121  */
 122 int drm_open(struct dev_open_args *ap)
 123 {
 124         struct cdev *kdev = ap->a_head.a_dev;
 125         struct file *filp = ap->a_fp;
 126         struct drm_device *dev = NULL;
 127         int minor_id = minor(kdev);
 128         struct drm_minor *minor;
 129         int retcode = 0;
 130         int need_setup = 0;
 131 /* old dfly variables below */
 132         int flags = ap->a_oflags;
 133         int fmt = 0;
 134         struct thread *p = curthread;
 135
 136         minor = idr_find(&drm_minors_idr, minor_id);
 137         if (!minor)
 138                 return -ENODEV;
 139
 140         if (!(dev = minor->dev))
 141                 return -ENODEV;
 142
 143         if (!dev->open_count++)
 144                 need_setup = 1;
 145
 146         retcode = drm_open_helper(kdev, flags, fmt, p, dev, filp);
 147         if (retcode)
 148                 goto err_undo;
 149         atomic_inc(&dev->counts[_DRM_STAT_OPENS]);
 150         if (need_setup) {
 151                 retcode = drm_setup(dev);
 152                 if (retcode)
 153                         goto err_undo;
 154         }
 155         return 0;
 156
 157 err_undo:
 158         dev->open_count--;
 159         return retcode;
 160 }
 161 EXPORT_SYMBOL(drm_open);
 162
 163 /**
 164  * Called whenever a process opens /dev/drm.
 165  *
 166  * \param inode device inode.
 167  * \param filp file pointer.
 168  * \param dev device.
 169  * \return zero on success or a negative number on failure.
 170  *
 171  * Creates and initializes a drm_file structure for the file private data in \p
 172  * filp and add it into the double linked list in \p dev.
 173  */
 174 static int drm_open_helper(struct cdev *kdev, int flags, int fmt, DRM_STRUCTPROC *p,
 175                     struct drm_device *dev, struct file *filp)
 176 {
 177         int minor_id = 0;
 178         struct drm_file *priv;
 179         int ret;
 180
 181         if (flags & O_EXCL)
 182                 return EBUSY; /* No exclusive opens */
 183         dev->flags = flags;
 184
 185         DRM_DEBUG("pid = %d, device = %s\n", DRM_CURRENTPID, devtoname(kdev));
 186
 187         priv = kmalloc(sizeof(*priv), M_DRM, M_WAITOK | M_NULLOK | M_ZERO);
 188         if (!priv)
 189                 return -ENOMEM;
 190
 191         filp->private_data = priv;
 192         priv->filp = filp;
 193         priv->uid               = p->td_proc->p_ucred->cr_svuid;
 194         priv->pid               = p->td_proc->p_pid;
 195         priv->minor = idr_find(&drm_minors_idr, minor_id);
 196         priv->ioctl_count = 0;
 197         /* for compatibility root is always authenticated */
 198         priv->authenticated     = DRM_SUSER(p);
 199         priv->lock_count = 0;
 200
 201         INIT_LIST_HEAD(&priv->lhead);
 202         INIT_LIST_HEAD(&priv->fbs);
 203         lockinit(&priv->fbs_lock, "dfbsl", 0, LK_CANRECURSE);
 204         INIT_LIST_HEAD(&priv->event_list);
 205         init_waitqueue_head(&priv->event_wait);
 206         priv->event_space = 4096; /* set aside 4k for event buffer */
 207
 208         if (dev->driver->driver_features & DRIVER_GEM)
 209                 drm_gem_open(dev, priv);
 210
 211         if (dev->driver->open) {
 212                 ret = dev->driver->open(dev, priv);
 213                 if (ret != 0)
 214                         goto out_free;
 215         }
 216
 217         /* if there is no current master make this fd it */
 218         mutex_lock(&dev->struct_mutex);
 219         if (!priv->minor->master) {
 220                 /* create a new master */
 221                 priv->minor->master = drm_master_create(priv->minor);
 222                 if (!priv->minor->master) {
 223                         mutex_unlock(&dev->struct_mutex);
 224                         ret = -ENOMEM;
 225                         goto out_free;
 226                 }
 227
 228                 priv->is_master = 1;
 229                 /* take another reference for the copy in the local file priv */
 230                 priv->master = drm_master_get(priv->minor->master);
 231
 232                 priv->authenticated = 1;
 233
 234                 mutex_unlock(&dev->struct_mutex);
 235                 if (dev->driver->master_create) {
 236                         ret = dev->driver->master_create(dev, priv->master);
 237                         if (ret) {
 238                                 mutex_lock(&dev->struct_mutex);
 239                                 /* drop both references if this fails */
 240                                 drm_master_put(&priv->minor->master);
 241                                 drm_master_put(&priv->master);
 242                                 mutex_unlock(&dev->struct_mutex);
 243                                 goto out_free;
 244                         }
 245                 }
 246                 mutex_lock(&dev->struct_mutex);
 247                 if (dev->driver->master_set) {
 248                         ret = dev->driver->master_set(dev, priv, true);
 249                         if (ret) {
 250                                 /* drop both references if this fails */
 251                                 drm_master_put(&priv->minor->master);
 252                                 drm_master_put(&priv->master);
 253                                 mutex_unlock(&dev->struct_mutex);
 254                                 goto out_free;
 255                         }
 256                 }
 257                 mutex_unlock(&dev->struct_mutex);
 258         } else {
 259                 /* get a reference to the master */
 260                 priv->master = drm_master_get(priv->minor->master);
 261                 mutex_unlock(&dev->struct_mutex);
 262         }
 263
 264         mutex_lock(&dev->struct_mutex);
 265         list_add(&priv->lhead, &dev->filelist);
 266         mutex_unlock(&dev->struct_mutex);
 267
 268         return 0;
 269       out_free:
 270         kfree(priv, M_DRM);
 271         filp->private_data = NULL;
 272         return ret;
 273 }
 274
 275 /**
 276  * Release file.
 277  *
 278  * \param inode device inode
 279  * \param file_priv DRM file private.
 280  * \return zero on success or a negative number on failure.
 281  *
 282  * If the hardware lock is held then free it, and take it again for the kernel
 283  * context since it's necessary to reclaim buffers. Unlink the file private
 284  * data from its list and free it. Decreases the open count and if it reaches
 285  * zero calls drm_lastclose().
 286  */
 287
 288 #if 0 /* old drm_release equivalent from DragonFly */
 289 void drm_cdevpriv_dtor(void *cd)
 290 {
 291         struct drm_file *file_priv = cd;
 292         struct drm_device *dev = file_priv->dev;
 293         int retcode = 0;
 294
 295         DRM_DEBUG("open_count = %d\n", dev->open_count);
 296
 297         DRM_LOCK(dev);
 298
 299         if (dev->driver->preclose != NULL)
 300                 dev->driver->preclose(dev, file_priv);
 301
 302         /* ========================================================
 303          * Begin inline drm_release
 304          */
 305
 306         DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n",
 307             DRM_CURRENTPID, (long)dev->dev, dev->open_count);
 308
 309         if (dev->driver->driver_features & DRIVER_GEM)
 310                 drm_gem_release(dev, file_priv);
 311
 312         if (dev->primary->master->lock.hw_lock
 313             && _DRM_LOCK_IS_HELD(dev->primary->master->lock.hw_lock->lock)
 314             && dev->primary->master->lock.file_priv == file_priv) {
 315                 DRM_DEBUG("Process %d dead, freeing lock for context %d\n",
 316                           DRM_CURRENTPID,
 317                           _DRM_LOCKING_CONTEXT(dev->primary->master->lock.hw_lock->lock));
 318                 if (dev->driver->reclaim_buffers_locked != NULL)
 319                         dev->driver->reclaim_buffers_locked(dev, file_priv);
 320
 321                 drm_lock_free(&dev->primary->master->lock,
 322                     _DRM_LOCKING_CONTEXT(dev->primary->master->lock.hw_lock->lock));
 323
 324                                 /* FIXME: may require heavy-handed reset of
 325                                    hardware at this point, possibly
 326                                    processed via a callback to the X
 327                                    server. */
 328         } else if (dev->driver->reclaim_buffers_locked != NULL &&
 329             dev->primary->master->lock.hw_lock != NULL) {
 330                 /* The lock is required to reclaim buffers */
 331                 for (;;) {
 332                         if (!dev->primary->master->lock.hw_lock) {
 333                                 /* Device has been unregistered */
 334                                 retcode = EINTR;
 335                                 break;
 336                         }
 337                         if (drm_lock_take(&dev->primary->master->lock, DRM_KERNEL_CONTEXT)) {
 338                                 dev->primary->master->lock.file_priv = file_priv;
 339                                 dev->primary->master->lock.lock_time = jiffies;
 340                                 atomic_inc(&dev->counts[_DRM_STAT_LOCKS]);
 341                                 break;  /* Got lock */
 342                         }
 343                         /* Contention */
 344                         retcode = DRM_LOCK_SLEEP(dev, &dev->primary->master->lock.lock_queue,
 345                             PCATCH, "drmlk2", 0);
 346                         if (retcode)
 347                                 break;
 348                 }
 349                 if (retcode == 0) {
 350                         dev->driver->reclaim_buffers_locked(dev, file_priv);
 351                         drm_lock_free(&dev->primary->master->lock, DRM_KERNEL_CONTEXT);
 352                 }
 353         }
 354
 355         if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) &&
 356             !dev->driver->reclaim_buffers_locked)
 357                 drm_reclaim_buffers(dev, file_priv);
 358
 359         funsetown(&dev->buf_sigio);
 360
 361         if (dev->driver->postclose != NULL)
 362                 dev->driver->postclose(dev, file_priv);
 363         list_del(&file_priv->lhead);
 364
 365
 366         /* ========================================================
 367          * End inline drm_release
 368          */
 369
 370         atomic_inc(&dev->counts[_DRM_STAT_CLOSES]);
 371         device_unbusy(dev->dev);
 372         if (--dev->open_count == 0) {
 373                 retcode = drm_lastclose(dev);
 374         }
 375
 376         DRM_UNLOCK(dev);
 377 }
 378 #endif
 379
 380 static void drm_unload(struct drm_device *dev)
 381 {
 382         int i;
 383
 384         DRM_DEBUG("\n");
 385
 386         drm_sysctl_cleanup(dev);
 387         if (dev->devnode != NULL)
 388                 destroy_dev(dev->devnode);
 389
 390         drm_ctxbitmap_cleanup(dev);
 391
 392         if (dev->driver->driver_features & DRIVER_GEM)
 393                 drm_gem_destroy(dev);
 394
 395         if (dev->agp && dev->agp->agp_mtrr) {
 396                 int __unused retcode;
 397
 398                 retcode = drm_mtrr_del(0, dev->agp->agp_info.ai_aperture_base,
 399                     dev->agp->agp_info.ai_aperture_size, DRM_MTRR_WC);
 400                 DRM_DEBUG("mtrr_del = %d", retcode);
 401         }
 402
 403         drm_vblank_cleanup(dev);
 404
 405         DRM_LOCK(dev);
 406         drm_lastclose(dev);
 407         DRM_UNLOCK(dev);
 408
 409         /* Clean up PCI resources allocated by drm_bufs.c.  We're not really
 410          * worried about resource consumption while the DRM is inactive (between
 411          * lastclose and firstopen or unload) because these aren't actually
 412          * taking up KVA, just keeping the PCI resource allocated.
 413          */
 414         for (i = 0; i < DRM_MAX_PCI_RESOURCE; i++) {
 415                 if (dev->pcir[i] == NULL)
 416                         continue;
 417                 bus_release_resource(dev->dev, SYS_RES_MEMORY,
 418                     dev->pcirid[i], dev->pcir[i]);
 419                 dev->pcir[i] = NULL;
 420         }
 421
 422         if (dev->agp) {
 423                 drm_free(dev->agp, M_DRM);
 424                 dev->agp = NULL;
 425         }
 426
 427         if (dev->driver->unload != NULL) {
 428                 DRM_LOCK(dev);
 429                 dev->driver->unload(dev);
 430                 DRM_UNLOCK(dev);
 431         }
 432
 433         drm_mem_uninit();
 434
 435         if (pci_disable_busmaster(dev->dev))
 436                 DRM_ERROR("Request to disable bus-master failed.\n");
 437
 438         lockuninit(&dev->vbl_lock);
 439         lockuninit(&dev->dev_lock);
 440         lockuninit(&dev->event_lock);
 441         lockuninit(&dev->struct_mutex);
 442 }
 443
 444 int drm_release(device_t kdev)
 445 {
 446         struct drm_device *dev;
 447
 448         dev = device_get_softc(kdev);
 449         drm_unload(dev);
 450         if (dev->irqr) {
 451                 bus_release_resource(dev->dev, SYS_RES_IRQ, dev->irqrid,
 452                     dev->irqr);
 453                 if (dev->msi_enabled) {
 454                         pci_release_msi(dev->dev);
 455                         DRM_INFO("MSI released\n");
 456                 }
 457         }
 458         return (0);
 459 }
 460
 461 static bool
 462 drm_dequeue_event(struct drm_device *dev, struct drm_file *file_priv,
 463     struct uio *uio, struct drm_pending_event **out)
 464 {
 465         struct drm_pending_event *e;
 466
 467         if (list_empty(&file_priv->event_list))
 468                 return (false);
 469         e = list_first_entry(&file_priv->event_list,
 470             struct drm_pending_event, link);
 471         if (e->event->length > uio->uio_resid)
 472                 return (false);
 473
 474         file_priv->event_space += e->event->length;
 475         list_del(&e->link);
 476         *out = e;
 477         return (true);
 478 }
 479
 480 int
 481 drm_read(struct dev_read_args *ap)
 482 {
 483         struct file *filp = ap->a_fp;
 484         struct drm_file *file_priv = filp->private_data;
 485         struct cdev *kdev = ap->a_head.a_dev;
 486         struct uio *uio = ap->a_uio;
 487         int ioflag = ap->a_ioflag;
 488         struct drm_device *dev;
 489         struct drm_pending_event *e;
 490         int error;
 491
 492         dev = drm_get_device_from_kdev(kdev);
 493         lockmgr(&dev->event_lock, LK_EXCLUSIVE);
 494         while (list_empty(&file_priv->event_list)) {
 495                 if ((ioflag & O_NONBLOCK) != 0) {
 496                         error = EAGAIN;
 497                         goto out;
 498                 }
 499                 error = lksleep(&file_priv->event_space, &dev->event_lock,
 500                    PCATCH, "drmrea", 0);
 501                if (error != 0)
 502                        goto out;
 503         }
 504         while (drm_dequeue_event(dev, file_priv, uio, &e)) {
 505                 lockmgr(&dev->event_lock, LK_RELEASE);
 506                 error = uiomove((caddr_t)e->event, e->event->length, uio);
 507                 e->destroy(e);
 508                 if (error != 0)
 509                         return (error);
 510                 lockmgr(&dev->event_lock, LK_EXCLUSIVE);
 511         }
 512 out:
 513         lockmgr(&dev->event_lock, LK_RELEASE);
 514         return (error);
 515 }
 516
 517 void
 518 drm_event_wakeup(struct drm_pending_event *e)
 519 {
 520         struct drm_file *file_priv = e->file_priv;
 521         struct drm_device *dev = file_priv->minor->dev;
 522
 523         KKASSERT(lockstatus(&dev->event_lock, curthread) != 0);
 524
 525         wakeup(&file_priv->event_space);
 526         KNOTE(&file_priv->dkq.ki_note, 0);
 527 }
 528
 529 static int
 530 drmfilt(struct knote *kn, long hint)
 531 {
 532         struct drm_file *file_priv = (struct drm_file *)kn->kn_hook;
 533         struct drm_device *dev = file_priv->minor->dev;
 534         int ready = 0;
 535
 536         lockmgr(&dev->event_lock, LK_EXCLUSIVE);
 537         if (!list_empty(&file_priv->event_list))
 538                 ready = 1;
 539         lockmgr(&dev->event_lock, LK_RELEASE);
 540
 541         return (ready);
 542 }
 543
 544 static void
 545 drmfilt_detach(struct knote *kn)
 546 {
 547         struct drm_file *file_priv = (struct drm_file *)kn->kn_hook;
 548         struct drm_device *dev = file_priv->minor->dev;
 549         struct klist *klist;
 550
 551         lockmgr(&dev->event_lock, LK_EXCLUSIVE);
 552         klist = &file_priv->dkq.ki_note;
 553         knote_remove(klist, kn);
 554         lockmgr(&dev->event_lock, LK_RELEASE);
 555 }
 556
 557 static struct filterops drmfiltops =
 558         { FILTEROP_ISFD, NULL, drmfilt_detach, drmfilt };
 559
 560 int
 561 drm_kqfilter(struct dev_kqfilter_args *ap)
 562 {
 563         struct file *filp = ap->a_fp;
 564         struct drm_file *file_priv = filp->private_data;
 565         struct drm_device *dev = file_priv->minor->dev;
 566         struct knote *kn = ap->a_kn;
 567         struct klist *klist;
 568
 569         ap->a_result = 0;
 570
 571         switch (kn->kn_filter) {
 572         case EVFILT_READ:
 573                 kn->kn_fop = &drmfiltops;
 574                 kn->kn_hook = (caddr_t)file_priv;
 575                 break;
 576         default:
 577                 ap->a_result = EOPNOTSUPP;
 578                 return (0);
 579         }
 580
 581         lockmgr(&dev->event_lock, LK_EXCLUSIVE);
 582         klist = &file_priv->dkq.ki_note;
 583         knote_insert(klist, kn);
 584         lockmgr(&dev->event_lock, LK_RELEASE);
 585
 586         return (0);
 587 }