drm_fops.c revision 862302ffe422378a5213f558fc5cdf62c37050a9
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/smp_lock.h> 40 41static int drm_open_helper(struct inode *inode, struct file *filp, 42 struct drm_device * dev); 43 44static 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) && 59 !drm_core_check_feature(dev, DRIVER_MODESET)) { 60 dev->buf_use = 0; 61 atomic_set(&dev->buf_alloc, 0); 62 63 i = drm_dma_setup(dev); 64 if (i < 0) 65 return i; 66 } 67 68 for (i = 0; i < ARRAY_SIZE(dev->counts); i++) 69 atomic_set(&dev->counts[i], 0); 70 71 dev->sigdata.lock = NULL; 72 73 dev->queue_count = 0; 74 dev->queue_reserved = 0; 75 dev->queue_slots = 0; 76 dev->queuelist = NULL; 77 dev->context_flag = 0; 78 dev->interrupt_flag = 0; 79 dev->dma_flag = 0; 80 dev->last_context = 0; 81 dev->last_switch = 0; 82 dev->last_checked = 0; 83 init_waitqueue_head(&dev->context_wait); 84 dev->if_version = 0; 85 86 dev->ctx_start = 0; 87 dev->lck_start = 0; 88 89 dev->buf_async = NULL; 90 init_waitqueue_head(&dev->buf_readers); 91 init_waitqueue_head(&dev->buf_writers); 92 93 DRM_DEBUG("\n"); 94 95 /* 96 * The kernel's context could be created here, but is now created 97 * in drm_dma_enqueue. This is more resource-efficient for 98 * hardware that does not do DMA, but may mean that 99 * drm_select_queue fails between the time the interrupt is 100 * initialized and the time the queues are initialized. 101 */ 102 103 return 0; 104} 105 106/** 107 * Open file. 108 * 109 * \param inode device inode 110 * \param filp file pointer. 111 * \return zero on success or a negative number on failure. 112 * 113 * Searches the DRM device with the same minor number, calls open_helper(), and 114 * increments the device open count. If the open count was previous at zero, 115 * i.e., it's the first that the device is open, then calls setup(). 116 */ 117int drm_open(struct inode *inode, struct file *filp) 118{ 119 struct drm_device *dev = NULL; 120 int minor_id = iminor(inode); 121 struct drm_minor *minor; 122 int retcode = 0; 123 124 minor = idr_find(&drm_minors_idr, minor_id); 125 if (!minor) 126 return -ENODEV; 127 128 if (!(dev = minor->dev)) 129 return -ENODEV; 130 131 retcode = drm_open_helper(inode, filp, dev); 132 if (!retcode) { 133 atomic_inc(&dev->counts[_DRM_STAT_OPENS]); 134 spin_lock(&dev->count_lock); 135 if (!dev->open_count++) { 136 spin_unlock(&dev->count_lock); 137 retcode = drm_setup(dev); 138 goto out; 139 } 140 spin_unlock(&dev->count_lock); 141 } 142out: 143 mutex_lock(&dev->struct_mutex); 144 if (minor->type == DRM_MINOR_LEGACY) { 145 BUG_ON((dev->dev_mapping != NULL) && 146 (dev->dev_mapping != inode->i_mapping)); 147 if (dev->dev_mapping == NULL) 148 dev->dev_mapping = inode->i_mapping; 149 } 150 mutex_unlock(&dev->struct_mutex); 151 152 return retcode; 153} 154EXPORT_SYMBOL(drm_open); 155 156/** 157 * File \c open operation. 158 * 159 * \param inode device inode. 160 * \param filp file pointer. 161 * 162 * Puts the dev->fops corresponding to the device minor number into 163 * \p filp, call the \c open method, and restore the file operations. 164 */ 165int drm_stub_open(struct inode *inode, struct file *filp) 166{ 167 struct drm_device *dev = NULL; 168 struct drm_minor *minor; 169 int minor_id = iminor(inode); 170 int err = -ENODEV; 171 const struct file_operations *old_fops; 172 173 DRM_DEBUG("\n"); 174 175 /* BKL pushdown: note that nothing else serializes idr_find() */ 176 lock_kernel(); 177 minor = idr_find(&drm_minors_idr, minor_id); 178 if (!minor) 179 goto out; 180 181 if (!(dev = minor->dev)) 182 goto out; 183 184 old_fops = filp->f_op; 185 filp->f_op = fops_get(&dev->driver->fops); 186 if (filp->f_op == NULL) { 187 filp->f_op = old_fops; 188 goto out; 189 } 190 if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) { 191 fops_put(filp->f_op); 192 filp->f_op = fops_get(old_fops); 193 } 194 fops_put(old_fops); 195 196out: 197 unlock_kernel(); 198 return err; 199} 200 201/** 202 * Check whether DRI will run on this CPU. 203 * 204 * \return non-zero if the DRI will run on this CPU, or zero otherwise. 205 */ 206static int drm_cpu_valid(void) 207{ 208#if defined(__i386__) 209 if (boot_cpu_data.x86 == 3) 210 return 0; /* No cmpxchg on a 386 */ 211#endif 212#if defined(__sparc__) && !defined(__sparc_v9__) 213 return 0; /* No cmpxchg before v9 sparc. */ 214#endif 215 return 1; 216} 217 218/** 219 * Called whenever a process opens /dev/drm. 220 * 221 * \param inode device inode. 222 * \param filp file pointer. 223 * \param dev device. 224 * \return zero on success or a negative number on failure. 225 * 226 * Creates and initializes a drm_file structure for the file private data in \p 227 * filp and add it into the double linked list in \p dev. 228 */ 229static int drm_open_helper(struct inode *inode, struct file *filp, 230 struct drm_device * dev) 231{ 232 int minor_id = iminor(inode); 233 struct drm_file *priv; 234 int ret; 235 236 if (filp->f_flags & O_EXCL) 237 return -EBUSY; /* No exclusive opens */ 238 if (!drm_cpu_valid()) 239 return -EINVAL; 240 241 DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id); 242 243 priv = kmalloc(sizeof(*priv), GFP_KERNEL); 244 if (!priv) 245 return -ENOMEM; 246 247 memset(priv, 0, sizeof(*priv)); 248 filp->private_data = priv; 249 priv->filp = filp; 250 priv->uid = current_euid(); 251 priv->pid = task_pid_nr(current); 252 priv->minor = idr_find(&drm_minors_idr, minor_id); 253 priv->ioctl_count = 0; 254 /* for compatibility root is always authenticated */ 255 priv->authenticated = capable(CAP_SYS_ADMIN); 256 priv->lock_count = 0; 257 258 INIT_LIST_HEAD(&priv->lhead); 259 INIT_LIST_HEAD(&priv->fbs); 260 INIT_LIST_HEAD(&priv->event_list); 261 init_waitqueue_head(&priv->event_wait); 262 priv->event_space = 4096; /* set aside 4k for event buffer */ 263 264 if (dev->driver->driver_features & DRIVER_GEM) 265 drm_gem_open(dev, priv); 266 267 if (dev->driver->open) { 268 ret = dev->driver->open(dev, priv); 269 if (ret < 0) 270 goto out_free; 271 } 272 273 274 /* if there is no current master make this fd it */ 275 mutex_lock(&dev->struct_mutex); 276 if (!priv->minor->master) { 277 /* create a new master */ 278 priv->minor->master = drm_master_create(priv->minor); 279 if (!priv->minor->master) { 280 mutex_unlock(&dev->struct_mutex); 281 ret = -ENOMEM; 282 goto out_free; 283 } 284 285 priv->is_master = 1; 286 /* take another reference for the copy in the local file priv */ 287 priv->master = drm_master_get(priv->minor->master); 288 289 priv->authenticated = 1; 290 291 mutex_unlock(&dev->struct_mutex); 292 if (dev->driver->master_create) { 293 ret = dev->driver->master_create(dev, priv->master); 294 if (ret) { 295 mutex_lock(&dev->struct_mutex); 296 /* drop both references if this fails */ 297 drm_master_put(&priv->minor->master); 298 drm_master_put(&priv->master); 299 mutex_unlock(&dev->struct_mutex); 300 goto out_free; 301 } 302 } 303 mutex_lock(&dev->struct_mutex); 304 if (dev->driver->master_set) { 305 ret = dev->driver->master_set(dev, priv, true); 306 if (ret) { 307 /* drop both references if this fails */ 308 drm_master_put(&priv->minor->master); 309 drm_master_put(&priv->master); 310 mutex_unlock(&dev->struct_mutex); 311 goto out_free; 312 } 313 } 314 mutex_unlock(&dev->struct_mutex); 315 } else { 316 /* get a reference to the master */ 317 priv->master = drm_master_get(priv->minor->master); 318 mutex_unlock(&dev->struct_mutex); 319 } 320 321 mutex_lock(&dev->struct_mutex); 322 list_add(&priv->lhead, &dev->filelist); 323 mutex_unlock(&dev->struct_mutex); 324 325#ifdef __alpha__ 326 /* 327 * Default the hose 328 */ 329 if (!dev->hose) { 330 struct pci_dev *pci_dev; 331 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); 332 if (pci_dev) { 333 dev->hose = pci_dev->sysdata; 334 pci_dev_put(pci_dev); 335 } 336 if (!dev->hose) { 337 struct pci_bus *b = pci_bus_b(pci_root_buses.next); 338 if (b) 339 dev->hose = b->sysdata; 340 } 341 } 342#endif 343 344 return 0; 345 out_free: 346 kfree(priv); 347 filp->private_data = NULL; 348 return ret; 349} 350 351/** No-op. */ 352int drm_fasync(int fd, struct file *filp, int on) 353{ 354 struct drm_file *priv = filp->private_data; 355 struct drm_device *dev = priv->minor->dev; 356 357 DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, 358 (long)old_encode_dev(priv->minor->device)); 359 return fasync_helper(fd, filp, on, &dev->buf_async); 360} 361EXPORT_SYMBOL(drm_fasync); 362 363/* 364 * Reclaim locked buffers; note that this may be a bad idea if the current 365 * context doesn't have the hw lock... 366 */ 367static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f) 368{ 369 struct drm_file *file_priv = f->private_data; 370 371 if (drm_i_have_hw_lock(dev, file_priv)) { 372 dev->driver->reclaim_buffers_locked(dev, file_priv); 373 } else { 374 unsigned long _end = jiffies + 3 * DRM_HZ; 375 int locked = 0; 376 377 drm_idlelock_take(&file_priv->master->lock); 378 379 /* 380 * Wait for a while. 381 */ 382 do { 383 spin_lock_bh(&file_priv->master->lock.spinlock); 384 locked = file_priv->master->lock.idle_has_lock; 385 spin_unlock_bh(&file_priv->master->lock.spinlock); 386 if (locked) 387 break; 388 schedule(); 389 } while (!time_after_eq(jiffies, _end)); 390 391 if (!locked) { 392 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n" 393 "\tdriver to use reclaim_buffers_idlelocked() instead.\n" 394 "\tI will go on reclaiming the buffers anyway.\n"); 395 } 396 397 dev->driver->reclaim_buffers_locked(dev, file_priv); 398 drm_idlelock_release(&file_priv->master->lock); 399 } 400} 401 402static void drm_master_release(struct drm_device *dev, struct file *filp) 403{ 404 struct drm_file *file_priv = filp->private_data; 405 406 if (dev->driver->reclaim_buffers_locked && 407 file_priv->master->lock.hw_lock) 408 drm_reclaim_locked_buffers(dev, filp); 409 410 if (dev->driver->reclaim_buffers_idlelocked && 411 file_priv->master->lock.hw_lock) { 412 drm_idlelock_take(&file_priv->master->lock); 413 dev->driver->reclaim_buffers_idlelocked(dev, file_priv); 414 drm_idlelock_release(&file_priv->master->lock); 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 drm_lock_free(&file_priv->master->lock, 422 _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 423 } 424 425 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && 426 !dev->driver->reclaim_buffers_locked) { 427 dev->driver->reclaim_buffers(dev, file_priv); 428 } 429} 430 431static void drm_events_release(struct drm_file *file_priv) 432{ 433 struct drm_device *dev = file_priv->minor->dev; 434 struct drm_pending_event *e, *et; 435 struct drm_pending_vblank_event *v, *vt; 436 unsigned long flags; 437 438 spin_lock_irqsave(&dev->event_lock, flags); 439 440 /* Remove pending flips */ 441 list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link) 442 if (v->base.file_priv == file_priv) { 443 list_del(&v->base.link); 444 drm_vblank_put(dev, v->pipe); 445 v->base.destroy(&v->base); 446 } 447 448 /* Remove unconsumed events */ 449 list_for_each_entry_safe(e, et, &file_priv->event_list, link) 450 e->destroy(e); 451 452 spin_unlock_irqrestore(&dev->event_lock, flags); 453} 454 455/** 456 * Release file. 457 * 458 * \param inode device inode 459 * \param file_priv DRM file private. 460 * \return zero on success or a negative number on failure. 461 * 462 * If the hardware lock is held then free it, and take it again for the kernel 463 * context since it's necessary to reclaim buffers. Unlink the file private 464 * data from its list and free it. Decreases the open count and if it reaches 465 * zero calls drm_lastclose(). 466 */ 467int drm_release(struct inode *inode, struct file *filp) 468{ 469 struct drm_file *file_priv = filp->private_data; 470 struct drm_device *dev = file_priv->minor->dev; 471 int retcode = 0; 472 473 lock_kernel(); 474 475 DRM_DEBUG("open_count = %d\n", dev->open_count); 476 477 if (dev->driver->preclose) 478 dev->driver->preclose(dev, file_priv); 479 480 /* ======================================================== 481 * Begin inline drm_release 482 */ 483 484 DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", 485 task_pid_nr(current), 486 (long)old_encode_dev(file_priv->minor->device), 487 dev->open_count); 488 489 /* if the master has gone away we can't do anything with the lock */ 490 if (file_priv->minor->master) 491 drm_master_release(dev, filp); 492 493 drm_events_release(file_priv); 494 495 if (dev->driver->driver_features & DRIVER_GEM) 496 drm_gem_release(dev, file_priv); 497 498 if (dev->driver->driver_features & DRIVER_MODESET) 499 drm_fb_release(file_priv); 500 501 mutex_lock(&dev->ctxlist_mutex); 502 if (!list_empty(&dev->ctxlist)) { 503 struct drm_ctx_list *pos, *n; 504 505 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) { 506 if (pos->tag == file_priv && 507 pos->handle != DRM_KERNEL_CONTEXT) { 508 if (dev->driver->context_dtor) 509 dev->driver->context_dtor(dev, 510 pos->handle); 511 512 drm_ctxbitmap_free(dev, pos->handle); 513 514 list_del(&pos->head); 515 kfree(pos); 516 --dev->ctx_count; 517 } 518 } 519 } 520 mutex_unlock(&dev->ctxlist_mutex); 521 522 mutex_lock(&dev->struct_mutex); 523 524 if (file_priv->is_master) { 525 struct drm_master *master = file_priv->master; 526 struct drm_file *temp; 527 list_for_each_entry(temp, &dev->filelist, lhead) { 528 if ((temp->master == file_priv->master) && 529 (temp != file_priv)) 530 temp->authenticated = 0; 531 } 532 533 /** 534 * Since the master is disappearing, so is the 535 * possibility to lock. 536 */ 537 538 if (master->lock.hw_lock) { 539 if (dev->sigdata.lock == master->lock.hw_lock) 540 dev->sigdata.lock = NULL; 541 master->lock.hw_lock = NULL; 542 master->lock.file_priv = NULL; 543 wake_up_interruptible_all(&master->lock.lock_queue); 544 } 545 546 if (file_priv->minor->master == file_priv->master) { 547 /* drop the reference held my the minor */ 548 if (dev->driver->master_drop) 549 dev->driver->master_drop(dev, file_priv, true); 550 drm_master_put(&file_priv->minor->master); 551 } 552 } 553 554 /* drop the reference held my the file priv */ 555 drm_master_put(&file_priv->master); 556 file_priv->is_master = 0; 557 list_del(&file_priv->lhead); 558 mutex_unlock(&dev->struct_mutex); 559 560 if (dev->driver->postclose) 561 dev->driver->postclose(dev, file_priv); 562 kfree(file_priv); 563 564 /* ======================================================== 565 * End inline drm_release 566 */ 567 568 atomic_inc(&dev->counts[_DRM_STAT_CLOSES]); 569 spin_lock(&dev->count_lock); 570 if (!--dev->open_count) { 571 if (atomic_read(&dev->ioctl_count)) { 572 DRM_ERROR("Device busy: %d\n", 573 atomic_read(&dev->ioctl_count)); 574 spin_unlock(&dev->count_lock); 575 unlock_kernel(); 576 return -EBUSY; 577 } 578 spin_unlock(&dev->count_lock); 579 unlock_kernel(); 580 return drm_lastclose(dev); 581 } 582 spin_unlock(&dev->count_lock); 583 584 unlock_kernel(); 585 586 return retcode; 587} 588EXPORT_SYMBOL(drm_release); 589 590static bool 591drm_dequeue_event(struct drm_file *file_priv, 592 size_t total, size_t max, struct drm_pending_event **out) 593{ 594 struct drm_device *dev = file_priv->minor->dev; 595 struct drm_pending_event *e; 596 unsigned long flags; 597 bool ret = false; 598 599 spin_lock_irqsave(&dev->event_lock, flags); 600 601 *out = NULL; 602 if (list_empty(&file_priv->event_list)) 603 goto out; 604 e = list_first_entry(&file_priv->event_list, 605 struct drm_pending_event, link); 606 if (e->event->length + total > max) 607 goto out; 608 609 file_priv->event_space += e->event->length; 610 list_del(&e->link); 611 *out = e; 612 ret = true; 613 614out: 615 spin_unlock_irqrestore(&dev->event_lock, flags); 616 return ret; 617} 618 619ssize_t drm_read(struct file *filp, char __user *buffer, 620 size_t count, loff_t *offset) 621{ 622 struct drm_file *file_priv = filp->private_data; 623 struct drm_pending_event *e; 624 size_t total; 625 ssize_t ret; 626 627 ret = wait_event_interruptible(file_priv->event_wait, 628 !list_empty(&file_priv->event_list)); 629 if (ret < 0) 630 return ret; 631 632 total = 0; 633 while (drm_dequeue_event(file_priv, total, count, &e)) { 634 if (copy_to_user(buffer + total, 635 e->event, e->event->length)) { 636 total = -EFAULT; 637 break; 638 } 639 640 total += e->event->length; 641 e->destroy(e); 642 } 643 644 return total; 645} 646EXPORT_SYMBOL(drm_read); 647 648unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) 649{ 650 struct drm_file *file_priv = filp->private_data; 651 unsigned int mask = 0; 652 653 poll_wait(filp, &file_priv->event_wait, wait); 654 655 if (!list_empty(&file_priv->event_list)) 656 mask |= POLLIN | POLLRDNORM; 657 658 return mask; 659} 660EXPORT_SYMBOL(drm_poll); 661