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 <linux/poll.h> 39#include <linux/slab.h> 40#include <linux/module.h> 41 42/* from BKL pushdown: note that nothing else serializes idr_find() */ 43DEFINE_MUTEX(drm_global_mutex); 44EXPORT_SYMBOL(drm_global_mutex); 45 46static int drm_open_helper(struct inode *inode, struct file *filp, 47 struct drm_device * dev); 48 49static int drm_setup(struct drm_device * dev) 50{ 51 int i; 52 int ret; 53 54 if (dev->driver->firstopen) { 55 ret = dev->driver->firstopen(dev); 56 if (ret != 0) 57 return ret; 58 } 59 60 atomic_set(&dev->ioctl_count, 0); 61 atomic_set(&dev->vma_count, 0); 62 63 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && 64 !drm_core_check_feature(dev, DRIVER_MODESET)) { 65 dev->buf_use = 0; 66 atomic_set(&dev->buf_alloc, 0); 67 68 i = drm_dma_setup(dev); 69 if (i < 0) 70 return i; 71 } 72 73 for (i = 0; i < ARRAY_SIZE(dev->counts); i++) 74 atomic_set(&dev->counts[i], 0); 75 76 dev->sigdata.lock = NULL; 77 78 dev->queue_count = 0; 79 dev->queue_reserved = 0; 80 dev->queue_slots = 0; 81 dev->queuelist = NULL; 82 dev->context_flag = 0; 83 dev->interrupt_flag = 0; 84 dev->dma_flag = 0; 85 dev->last_context = 0; 86 dev->last_switch = 0; 87 dev->last_checked = 0; 88 init_waitqueue_head(&dev->context_wait); 89 dev->if_version = 0; 90 91 dev->ctx_start = 0; 92 dev->lck_start = 0; 93 94 dev->buf_async = NULL; 95 init_waitqueue_head(&dev->buf_readers); 96 init_waitqueue_head(&dev->buf_writers); 97 98 DRM_DEBUG("\n"); 99 100 /* 101 * The kernel's context could be created here, but is now created 102 * in drm_dma_enqueue. This is more resource-efficient for 103 * hardware that does not do DMA, but may mean that 104 * drm_select_queue fails between the time the interrupt is 105 * initialized and the time the queues are initialized. 106 */ 107 108 return 0; 109} 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 */ 122int drm_open(struct inode *inode, struct file *filp) 123{ 124 struct drm_device *dev = NULL; 125 int minor_id = iminor(inode); 126 struct drm_minor *minor; 127 int retcode = 0; 128 129 minor = idr_find(&drm_minors_idr, minor_id); 130 if (!minor) 131 return -ENODEV; 132 133 if (!(dev = minor->dev)) 134 return -ENODEV; 135 136 if (drm_device_is_unplugged(dev)) 137 return -ENODEV; 138 139 retcode = drm_open_helper(inode, filp, dev); 140 if (!retcode) { 141 atomic_inc(&dev->counts[_DRM_STAT_OPENS]); 142 if (!dev->open_count++) 143 retcode = drm_setup(dev); 144 } 145 if (!retcode) { 146 mutex_lock(&dev->struct_mutex); 147 if (minor->type == DRM_MINOR_LEGACY) { 148 if (dev->dev_mapping == NULL) 149 dev->dev_mapping = inode->i_mapping; 150 else if (dev->dev_mapping != inode->i_mapping) 151 retcode = -ENODEV; 152 } 153 mutex_unlock(&dev->struct_mutex); 154 } 155 156 return retcode; 157} 158EXPORT_SYMBOL(drm_open); 159 160/** 161 * File \c open operation. 162 * 163 * \param inode device inode. 164 * \param filp file pointer. 165 * 166 * Puts the dev->fops corresponding to the device minor number into 167 * \p filp, call the \c open method, and restore the file operations. 168 */ 169int drm_stub_open(struct inode *inode, struct file *filp) 170{ 171 struct drm_device *dev = NULL; 172 struct drm_minor *minor; 173 int minor_id = iminor(inode); 174 int err = -ENODEV; 175 const struct file_operations *old_fops; 176 177 DRM_DEBUG("\n"); 178 179 mutex_lock(&drm_global_mutex); 180 minor = idr_find(&drm_minors_idr, minor_id); 181 if (!minor) 182 goto out; 183 184 if (!(dev = minor->dev)) 185 goto out; 186 187 if (drm_device_is_unplugged(dev)) 188 goto out; 189 190 old_fops = filp->f_op; 191 filp->f_op = fops_get(dev->driver->fops); 192 if (filp->f_op == NULL) { 193 filp->f_op = old_fops; 194 goto out; 195 } 196 if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) { 197 fops_put(filp->f_op); 198 filp->f_op = fops_get(old_fops); 199 } 200 fops_put(old_fops); 201 202out: 203 mutex_unlock(&drm_global_mutex); 204 return err; 205} 206 207/** 208 * Check whether DRI will run on this CPU. 209 * 210 * \return non-zero if the DRI will run on this CPU, or zero otherwise. 211 */ 212static int drm_cpu_valid(void) 213{ 214#if defined(__i386__) 215 if (boot_cpu_data.x86 == 3) 216 return 0; /* No cmpxchg on a 386 */ 217#endif 218#if defined(__sparc__) && !defined(__sparc_v9__) 219 return 0; /* No cmpxchg before v9 sparc. */ 220#endif 221 return 1; 222} 223 224/** 225 * Called whenever a process opens /dev/drm. 226 * 227 * \param inode device inode. 228 * \param filp file pointer. 229 * \param dev device. 230 * \return zero on success or a negative number on failure. 231 * 232 * Creates and initializes a drm_file structure for the file private data in \p 233 * filp and add it into the double linked list in \p dev. 234 */ 235static int drm_open_helper(struct inode *inode, struct file *filp, 236 struct drm_device * dev) 237{ 238 int minor_id = iminor(inode); 239 struct drm_file *priv; 240 int ret; 241 242 if (filp->f_flags & O_EXCL) 243 return -EBUSY; /* No exclusive opens */ 244 if (!drm_cpu_valid()) 245 return -EINVAL; 246 if (dev->switch_power_state != DRM_SWITCH_POWER_ON) 247 return -EINVAL; 248 249 DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id); 250 251 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 252 if (!priv) 253 return -ENOMEM; 254 255 filp->private_data = priv; 256 priv->filp = filp; 257 priv->uid = current_euid(); 258 priv->pid = task_pid_nr(current); 259 priv->minor = idr_find(&drm_minors_idr, minor_id); 260 priv->ioctl_count = 0; 261 /* for compatibility root is always authenticated */ 262 priv->authenticated = capable(CAP_SYS_ADMIN); 263 priv->lock_count = 0; 264 265 INIT_LIST_HEAD(&priv->lhead); 266 INIT_LIST_HEAD(&priv->fbs); 267 INIT_LIST_HEAD(&priv->event_list); 268 init_waitqueue_head(&priv->event_wait); 269 priv->event_space = 4096; /* set aside 4k for event buffer */ 270 271 if (dev->driver->driver_features & DRIVER_GEM) 272 drm_gem_open(dev, priv); 273 274 if (drm_core_check_feature(dev, DRIVER_PRIME)) 275 drm_prime_init_file_private(&priv->prime); 276 277 if (dev->driver->open) { 278 ret = dev->driver->open(dev, priv); 279 if (ret < 0) 280 goto out_free; 281 } 282 283 284 /* if there is no current master make this fd it */ 285 mutex_lock(&dev->struct_mutex); 286 if (!priv->minor->master) { 287 /* create a new master */ 288 priv->minor->master = drm_master_create(priv->minor); 289 if (!priv->minor->master) { 290 mutex_unlock(&dev->struct_mutex); 291 ret = -ENOMEM; 292 goto out_free; 293 } 294 295 priv->is_master = 1; 296 /* take another reference for the copy in the local file priv */ 297 priv->master = drm_master_get(priv->minor->master); 298 299 priv->authenticated = 1; 300 301 mutex_unlock(&dev->struct_mutex); 302 if (dev->driver->master_create) { 303 ret = dev->driver->master_create(dev, priv->master); 304 if (ret) { 305 mutex_lock(&dev->struct_mutex); 306 /* drop both references if this fails */ 307 drm_master_put(&priv->minor->master); 308 drm_master_put(&priv->master); 309 mutex_unlock(&dev->struct_mutex); 310 goto out_free; 311 } 312 } 313 mutex_lock(&dev->struct_mutex); 314 if (dev->driver->master_set) { 315 ret = dev->driver->master_set(dev, priv, true); 316 if (ret) { 317 /* drop both references if this fails */ 318 drm_master_put(&priv->minor->master); 319 drm_master_put(&priv->master); 320 mutex_unlock(&dev->struct_mutex); 321 goto out_free; 322 } 323 } 324 mutex_unlock(&dev->struct_mutex); 325 } else { 326 /* get a reference to the master */ 327 priv->master = drm_master_get(priv->minor->master); 328 mutex_unlock(&dev->struct_mutex); 329 } 330 331 mutex_lock(&dev->struct_mutex); 332 list_add(&priv->lhead, &dev->filelist); 333 mutex_unlock(&dev->struct_mutex); 334 335#ifdef __alpha__ 336 /* 337 * Default the hose 338 */ 339 if (!dev->hose) { 340 struct pci_dev *pci_dev; 341 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); 342 if (pci_dev) { 343 dev->hose = pci_dev->sysdata; 344 pci_dev_put(pci_dev); 345 } 346 if (!dev->hose) { 347 struct pci_bus *b = pci_bus_b(pci_root_buses.next); 348 if (b) 349 dev->hose = b->sysdata; 350 } 351 } 352#endif 353 354 return 0; 355 out_free: 356 kfree(priv); 357 filp->private_data = NULL; 358 return ret; 359} 360 361/** No-op. */ 362int drm_fasync(int fd, struct file *filp, int on) 363{ 364 struct drm_file *priv = filp->private_data; 365 struct drm_device *dev = priv->minor->dev; 366 367 DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, 368 (long)old_encode_dev(priv->minor->device)); 369 return fasync_helper(fd, filp, on, &dev->buf_async); 370} 371EXPORT_SYMBOL(drm_fasync); 372 373/* 374 * Reclaim locked buffers; note that this may be a bad idea if the current 375 * context doesn't have the hw lock... 376 */ 377static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f) 378{ 379 struct drm_file *file_priv = f->private_data; 380 381 if (drm_i_have_hw_lock(dev, file_priv)) { 382 dev->driver->reclaim_buffers_locked(dev, file_priv); 383 } else { 384 unsigned long _end = jiffies + 3 * DRM_HZ; 385 int locked = 0; 386 387 drm_idlelock_take(&file_priv->master->lock); 388 389 /* 390 * Wait for a while. 391 */ 392 do { 393 spin_lock_bh(&file_priv->master->lock.spinlock); 394 locked = file_priv->master->lock.idle_has_lock; 395 spin_unlock_bh(&file_priv->master->lock.spinlock); 396 if (locked) 397 break; 398 schedule(); 399 } while (!time_after_eq(jiffies, _end)); 400 401 if (!locked) { 402 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n" 403 "\tdriver to use reclaim_buffers_idlelocked() instead.\n" 404 "\tI will go on reclaiming the buffers anyway.\n"); 405 } 406 407 dev->driver->reclaim_buffers_locked(dev, file_priv); 408 drm_idlelock_release(&file_priv->master->lock); 409 } 410} 411 412static void drm_master_release(struct drm_device *dev, struct file *filp) 413{ 414 struct drm_file *file_priv = filp->private_data; 415 416 if (dev->driver->reclaim_buffers_locked && 417 file_priv->master->lock.hw_lock) 418 drm_reclaim_locked_buffers(dev, filp); 419 420 if (dev->driver->reclaim_buffers_idlelocked && 421 file_priv->master->lock.hw_lock) { 422 drm_idlelock_take(&file_priv->master->lock); 423 dev->driver->reclaim_buffers_idlelocked(dev, file_priv); 424 drm_idlelock_release(&file_priv->master->lock); 425 } 426 427 428 if (drm_i_have_hw_lock(dev, file_priv)) { 429 DRM_DEBUG("File %p released, freeing lock for context %d\n", 430 filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 431 drm_lock_free(&file_priv->master->lock, 432 _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 433 } 434 435 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && 436 !dev->driver->reclaim_buffers_locked) { 437 dev->driver->reclaim_buffers(dev, file_priv); 438 } 439} 440 441static void drm_events_release(struct drm_file *file_priv) 442{ 443 struct drm_device *dev = file_priv->minor->dev; 444 struct drm_pending_event *e, *et; 445 struct drm_pending_vblank_event *v, *vt; 446 unsigned long flags; 447 448 spin_lock_irqsave(&dev->event_lock, flags); 449 450 /* Remove pending flips */ 451 list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link) 452 if (v->base.file_priv == file_priv) { 453 list_del(&v->base.link); 454 drm_vblank_put(dev, v->pipe); 455 v->base.destroy(&v->base); 456 } 457 458 /* Remove unconsumed events */ 459 list_for_each_entry_safe(e, et, &file_priv->event_list, link) 460 e->destroy(e); 461 462 spin_unlock_irqrestore(&dev->event_lock, flags); 463} 464 465/** 466 * Release file. 467 * 468 * \param inode device inode 469 * \param file_priv DRM file private. 470 * \return zero on success or a negative number on failure. 471 * 472 * If the hardware lock is held then free it, and take it again for the kernel 473 * context since it's necessary to reclaim buffers. Unlink the file private 474 * data from its list and free it. Decreases the open count and if it reaches 475 * zero calls drm_lastclose(). 476 */ 477int drm_release(struct inode *inode, struct file *filp) 478{ 479 struct drm_file *file_priv = filp->private_data; 480 struct drm_device *dev = file_priv->minor->dev; 481 int retcode = 0; 482 483 mutex_lock(&drm_global_mutex); 484 485 DRM_DEBUG("open_count = %d\n", dev->open_count); 486 487 if (dev->driver->preclose) 488 dev->driver->preclose(dev, file_priv); 489 490 /* ======================================================== 491 * Begin inline drm_release 492 */ 493 494 DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", 495 task_pid_nr(current), 496 (long)old_encode_dev(file_priv->minor->device), 497 dev->open_count); 498 499 /* Release any auth tokens that might point to this file_priv, 500 (do that under the drm_global_mutex) */ 501 if (file_priv->magic) 502 (void) drm_remove_magic(file_priv->master, file_priv->magic); 503 504 /* if the master has gone away we can't do anything with the lock */ 505 if (file_priv->minor->master) 506 drm_master_release(dev, filp); 507 508 drm_events_release(file_priv); 509 510 if (dev->driver->driver_features & DRIVER_MODESET) 511 drm_fb_release(file_priv); 512 513 if (dev->driver->driver_features & DRIVER_GEM) 514 drm_gem_release(dev, file_priv); 515 516 mutex_lock(&dev->ctxlist_mutex); 517 if (!list_empty(&dev->ctxlist)) { 518 struct drm_ctx_list *pos, *n; 519 520 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) { 521 if (pos->tag == file_priv && 522 pos->handle != DRM_KERNEL_CONTEXT) { 523 if (dev->driver->context_dtor) 524 dev->driver->context_dtor(dev, 525 pos->handle); 526 527 drm_ctxbitmap_free(dev, pos->handle); 528 529 list_del(&pos->head); 530 kfree(pos); 531 --dev->ctx_count; 532 } 533 } 534 } 535 mutex_unlock(&dev->ctxlist_mutex); 536 537 mutex_lock(&dev->struct_mutex); 538 539 if (file_priv->is_master) { 540 struct drm_master *master = file_priv->master; 541 struct drm_file *temp; 542 list_for_each_entry(temp, &dev->filelist, lhead) { 543 if ((temp->master == file_priv->master) && 544 (temp != file_priv)) 545 temp->authenticated = 0; 546 } 547 548 /** 549 * Since the master is disappearing, so is the 550 * possibility to lock. 551 */ 552 553 if (master->lock.hw_lock) { 554 if (dev->sigdata.lock == master->lock.hw_lock) 555 dev->sigdata.lock = NULL; 556 master->lock.hw_lock = NULL; 557 master->lock.file_priv = NULL; 558 wake_up_interruptible_all(&master->lock.lock_queue); 559 } 560 561 if (file_priv->minor->master == file_priv->master) { 562 /* drop the reference held my the minor */ 563 if (dev->driver->master_drop) 564 dev->driver->master_drop(dev, file_priv, true); 565 drm_master_put(&file_priv->minor->master); 566 } 567 } 568 569 /* drop the reference held my the file priv */ 570 drm_master_put(&file_priv->master); 571 file_priv->is_master = 0; 572 list_del(&file_priv->lhead); 573 mutex_unlock(&dev->struct_mutex); 574 575 if (dev->driver->postclose) 576 dev->driver->postclose(dev, file_priv); 577 578 if (drm_core_check_feature(dev, DRIVER_PRIME)) 579 drm_prime_destroy_file_private(&file_priv->prime); 580 581 kfree(file_priv); 582 583 /* ======================================================== 584 * End inline drm_release 585 */ 586 587 atomic_inc(&dev->counts[_DRM_STAT_CLOSES]); 588 if (!--dev->open_count) { 589 if (atomic_read(&dev->ioctl_count)) { 590 DRM_ERROR("Device busy: %d\n", 591 atomic_read(&dev->ioctl_count)); 592 retcode = -EBUSY; 593 } else 594 retcode = drm_lastclose(dev); 595 if (drm_device_is_unplugged(dev)) 596 drm_put_dev(dev); 597 } 598 mutex_unlock(&drm_global_mutex); 599 600 return retcode; 601} 602EXPORT_SYMBOL(drm_release); 603 604static bool 605drm_dequeue_event(struct drm_file *file_priv, 606 size_t total, size_t max, struct drm_pending_event **out) 607{ 608 struct drm_device *dev = file_priv->minor->dev; 609 struct drm_pending_event *e; 610 unsigned long flags; 611 bool ret = false; 612 613 spin_lock_irqsave(&dev->event_lock, flags); 614 615 *out = NULL; 616 if (list_empty(&file_priv->event_list)) 617 goto out; 618 e = list_first_entry(&file_priv->event_list, 619 struct drm_pending_event, link); 620 if (e->event->length + total > max) 621 goto out; 622 623 file_priv->event_space += e->event->length; 624 list_del(&e->link); 625 *out = e; 626 ret = true; 627 628out: 629 spin_unlock_irqrestore(&dev->event_lock, flags); 630 return ret; 631} 632 633ssize_t drm_read(struct file *filp, char __user *buffer, 634 size_t count, loff_t *offset) 635{ 636 struct drm_file *file_priv = filp->private_data; 637 struct drm_pending_event *e; 638 size_t total; 639 ssize_t ret; 640 641 ret = wait_event_interruptible(file_priv->event_wait, 642 !list_empty(&file_priv->event_list)); 643 if (ret < 0) 644 return ret; 645 646 total = 0; 647 while (drm_dequeue_event(file_priv, total, count, &e)) { 648 if (copy_to_user(buffer + total, 649 e->event, e->event->length)) { 650 total = -EFAULT; 651 break; 652 } 653 654 total += e->event->length; 655 e->destroy(e); 656 } 657 658 return total; 659} 660EXPORT_SYMBOL(drm_read); 661 662unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) 663{ 664 struct drm_file *file_priv = filp->private_data; 665 unsigned int mask = 0; 666 667 poll_wait(filp, &file_priv->event_wait, wait); 668 669 if (!list_empty(&file_priv->event_list)) 670 mask |= POLLIN | POLLRDNORM; 671 672 return mask; 673} 674EXPORT_SYMBOL(drm_poll); 675