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 <drm/drmP.h> 38#include <linux/poll.h> 39#include <linux/slab.h> 40#include <linux/module.h> 41#include "drm_legacy.h" 42#include "drm_internal.h" 43 44/* from BKL pushdown */ 45DEFINE_MUTEX(drm_global_mutex); 46 47static int drm_open_helper(struct file *filp, struct drm_minor *minor); 48 49static int drm_setup(struct drm_device * dev) 50{ 51 int ret; 52 53 if (dev->driver->firstopen && 54 !drm_core_check_feature(dev, DRIVER_MODESET)) { 55 ret = dev->driver->firstopen(dev); 56 if (ret != 0) 57 return ret; 58 } 59 60 ret = drm_legacy_dma_setup(dev); 61 if (ret < 0) 62 return ret; 63 64 65 DRM_DEBUG("\n"); 66 return 0; 67} 68 69/** 70 * Open file. 71 * 72 * \param inode device inode 73 * \param filp file pointer. 74 * \return zero on success or a negative number on failure. 75 * 76 * Searches the DRM device with the same minor number, calls open_helper(), and 77 * increments the device open count. If the open count was previous at zero, 78 * i.e., it's the first that the device is open, then calls setup(). 79 */ 80int drm_open(struct inode *inode, struct file *filp) 81{ 82 struct drm_device *dev; 83 struct drm_minor *minor; 84 int retcode; 85 int need_setup = 0; 86 87 minor = drm_minor_acquire(iminor(inode)); 88 if (IS_ERR(minor)) 89 return PTR_ERR(minor); 90 91 dev = minor->dev; 92 if (!dev->open_count++) 93 need_setup = 1; 94 95 /* share address_space across all char-devs of a single device */ 96 filp->f_mapping = dev->anon_inode->i_mapping; 97 98 retcode = drm_open_helper(filp, minor); 99 if (retcode) 100 goto err_undo; 101 if (need_setup) { 102 retcode = drm_setup(dev); 103 if (retcode) 104 goto err_undo; 105 } 106 return 0; 107 108err_undo: 109 dev->open_count--; 110 drm_minor_release(minor); 111 return retcode; 112} 113EXPORT_SYMBOL(drm_open); 114 115/** 116 * Check whether DRI will run on this CPU. 117 * 118 * \return non-zero if the DRI will run on this CPU, or zero otherwise. 119 */ 120static int drm_cpu_valid(void) 121{ 122#if defined(__sparc__) && !defined(__sparc_v9__) 123 return 0; /* No cmpxchg before v9 sparc. */ 124#endif 125 return 1; 126} 127 128/** 129 * Called whenever a process opens /dev/drm. 130 * 131 * \param filp file pointer. 132 * \param minor acquired minor-object. 133 * \return zero on success or a negative number on failure. 134 * 135 * Creates and initializes a drm_file structure for the file private data in \p 136 * filp and add it into the double linked list in \p dev. 137 */ 138static int drm_open_helper(struct file *filp, struct drm_minor *minor) 139{ 140 struct drm_device *dev = minor->dev; 141 struct drm_file *priv; 142 int ret; 143 144 if (filp->f_flags & O_EXCL) 145 return -EBUSY; /* No exclusive opens */ 146 if (!drm_cpu_valid()) 147 return -EINVAL; 148 if (dev->switch_power_state != DRM_SWITCH_POWER_ON && dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF) 149 return -EINVAL; 150 151 DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor->index); 152 153 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 154 if (!priv) 155 return -ENOMEM; 156 157 filp->private_data = priv; 158 priv->filp = filp; 159 priv->uid = current_euid(); 160 priv->pid = get_pid(task_pid(current)); 161 priv->minor = minor; 162 163 /* for compatibility root is always authenticated */ 164 priv->authenticated = capable(CAP_SYS_ADMIN); 165 priv->lock_count = 0; 166 167 INIT_LIST_HEAD(&priv->lhead); 168 INIT_LIST_HEAD(&priv->fbs); 169 mutex_init(&priv->fbs_lock); 170 INIT_LIST_HEAD(&priv->event_list); 171 init_waitqueue_head(&priv->event_wait); 172 priv->event_space = 4096; /* set aside 4k for event buffer */ 173 174 if (drm_core_check_feature(dev, DRIVER_GEM)) 175 drm_gem_open(dev, priv); 176 177 if (drm_core_check_feature(dev, DRIVER_PRIME)) 178 drm_prime_init_file_private(&priv->prime); 179 180 if (dev->driver->open) { 181 ret = dev->driver->open(dev, priv); 182 if (ret < 0) 183 goto out_prime_destroy; 184 } 185 186 /* if there is no current master make this fd it, but do not create 187 * any master object for render clients */ 188 mutex_lock(&dev->master_mutex); 189 if (drm_is_primary_client(priv) && !priv->minor->master) { 190 /* create a new master */ 191 priv->minor->master = drm_master_create(priv->minor); 192 if (!priv->minor->master) { 193 ret = -ENOMEM; 194 goto out_close; 195 } 196 197 priv->is_master = 1; 198 /* take another reference for the copy in the local file priv */ 199 priv->master = drm_master_get(priv->minor->master); 200 priv->authenticated = 1; 201 202 if (dev->driver->master_create) { 203 ret = dev->driver->master_create(dev, priv->master); 204 if (ret) { 205 /* drop both references if this fails */ 206 drm_master_put(&priv->minor->master); 207 drm_master_put(&priv->master); 208 goto out_close; 209 } 210 } 211 if (dev->driver->master_set) { 212 ret = dev->driver->master_set(dev, priv, true); 213 if (ret) { 214 /* drop both references if this fails */ 215 drm_master_put(&priv->minor->master); 216 drm_master_put(&priv->master); 217 goto out_close; 218 } 219 } 220 } else if (drm_is_primary_client(priv)) { 221 /* get a reference to the master */ 222 priv->master = drm_master_get(priv->minor->master); 223 } 224 mutex_unlock(&dev->master_mutex); 225 226 mutex_lock(&dev->struct_mutex); 227 list_add(&priv->lhead, &dev->filelist); 228 mutex_unlock(&dev->struct_mutex); 229 230#ifdef __alpha__ 231 /* 232 * Default the hose 233 */ 234 if (!dev->hose) { 235 struct pci_dev *pci_dev; 236 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); 237 if (pci_dev) { 238 dev->hose = pci_dev->sysdata; 239 pci_dev_put(pci_dev); 240 } 241 if (!dev->hose) { 242 struct pci_bus *b = list_entry(pci_root_buses.next, 243 struct pci_bus, node); 244 if (b) 245 dev->hose = b->sysdata; 246 } 247 } 248#endif 249 250 return 0; 251 252out_close: 253 mutex_unlock(&dev->master_mutex); 254 if (dev->driver->postclose) 255 dev->driver->postclose(dev, priv); 256out_prime_destroy: 257 if (drm_core_check_feature(dev, DRIVER_PRIME)) 258 drm_prime_destroy_file_private(&priv->prime); 259 if (drm_core_check_feature(dev, DRIVER_GEM)) 260 drm_gem_release(dev, priv); 261 put_pid(priv->pid); 262 kfree(priv); 263 filp->private_data = NULL; 264 return ret; 265} 266 267static void drm_master_release(struct drm_device *dev, struct file *filp) 268{ 269 struct drm_file *file_priv = filp->private_data; 270 271 if (drm_legacy_i_have_hw_lock(dev, file_priv)) { 272 DRM_DEBUG("File %p released, freeing lock for context %d\n", 273 filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 274 drm_legacy_lock_free(&file_priv->master->lock, 275 _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 276 } 277} 278 279static void drm_events_release(struct drm_file *file_priv) 280{ 281 struct drm_device *dev = file_priv->minor->dev; 282 struct drm_pending_event *e, *et; 283 struct drm_pending_vblank_event *v, *vt; 284 unsigned long flags; 285 286 spin_lock_irqsave(&dev->event_lock, flags); 287 288 /* Remove pending flips */ 289 list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link) 290 if (v->base.file_priv == file_priv) { 291 list_del(&v->base.link); 292 drm_vblank_put(dev, v->pipe); 293 v->base.destroy(&v->base); 294 } 295 296 /* Remove unconsumed events */ 297 list_for_each_entry_safe(e, et, &file_priv->event_list, link) { 298 list_del(&e->link); 299 e->destroy(e); 300 } 301 302 spin_unlock_irqrestore(&dev->event_lock, flags); 303} 304 305/** 306 * drm_legacy_dev_reinit 307 * 308 * Reinitializes a legacy/ums drm device in it's lastclose function. 309 */ 310static void drm_legacy_dev_reinit(struct drm_device *dev) 311{ 312 if (drm_core_check_feature(dev, DRIVER_MODESET)) 313 return; 314 315 dev->sigdata.lock = NULL; 316 317 dev->context_flag = 0; 318 dev->last_context = 0; 319 dev->if_version = 0; 320} 321 322/** 323 * Take down the DRM device. 324 * 325 * \param dev DRM device structure. 326 * 327 * Frees every resource in \p dev. 328 * 329 * \sa drm_device 330 */ 331int drm_lastclose(struct drm_device * dev) 332{ 333 DRM_DEBUG("\n"); 334 335 if (dev->driver->lastclose) 336 dev->driver->lastclose(dev); 337 DRM_DEBUG("driver lastclose completed\n"); 338 339 if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET)) 340 drm_irq_uninstall(dev); 341 342 mutex_lock(&dev->struct_mutex); 343 344 drm_agp_clear(dev); 345 346 drm_legacy_sg_cleanup(dev); 347 drm_legacy_vma_flush(dev); 348 drm_legacy_dma_takedown(dev); 349 350 mutex_unlock(&dev->struct_mutex); 351 352 drm_legacy_dev_reinit(dev); 353 354 DRM_DEBUG("lastclose completed\n"); 355 return 0; 356} 357 358/** 359 * Release file. 360 * 361 * \param inode device inode 362 * \param file_priv DRM file private. 363 * \return zero on success or a negative number on failure. 364 * 365 * If the hardware lock is held then free it, and take it again for the kernel 366 * context since it's necessary to reclaim buffers. Unlink the file private 367 * data from its list and free it. Decreases the open count and if it reaches 368 * zero calls drm_lastclose(). 369 */ 370int drm_release(struct inode *inode, struct file *filp) 371{ 372 struct drm_file *file_priv = filp->private_data; 373 struct drm_minor *minor = file_priv->minor; 374 struct drm_device *dev = minor->dev; 375 int retcode = 0; 376 377 mutex_lock(&drm_global_mutex); 378 379 DRM_DEBUG("open_count = %d\n", dev->open_count); 380 381 mutex_lock(&dev->struct_mutex); 382 list_del(&file_priv->lhead); 383 mutex_unlock(&dev->struct_mutex); 384 385 if (dev->driver->preclose) 386 dev->driver->preclose(dev, file_priv); 387 388 /* ======================================================== 389 * Begin inline drm_release 390 */ 391 392 DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", 393 task_pid_nr(current), 394 (long)old_encode_dev(file_priv->minor->kdev->devt), 395 dev->open_count); 396 397 /* Release any auth tokens that might point to this file_priv, 398 (do that under the drm_global_mutex) */ 399 if (file_priv->magic) 400 (void) drm_remove_magic(file_priv->master, file_priv->magic); 401 402 /* if the master has gone away we can't do anything with the lock */ 403 if (file_priv->minor->master) 404 drm_master_release(dev, filp); 405 406 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) 407 drm_legacy_reclaim_buffers(dev, file_priv); 408 409 drm_events_release(file_priv); 410 411 if (drm_core_check_feature(dev, DRIVER_MODESET)) 412 drm_fb_release(file_priv); 413 414 if (drm_core_check_feature(dev, DRIVER_GEM)) 415 drm_gem_release(dev, file_priv); 416 417 drm_legacy_ctxbitmap_flush(dev, file_priv); 418 419 mutex_lock(&dev->master_mutex); 420 421 if (file_priv->is_master) { 422 struct drm_master *master = file_priv->master; 423 424 /** 425 * Since the master is disappearing, so is the 426 * possibility to lock. 427 */ 428 mutex_lock(&dev->struct_mutex); 429 if (master->lock.hw_lock) { 430 if (dev->sigdata.lock == master->lock.hw_lock) 431 dev->sigdata.lock = NULL; 432 master->lock.hw_lock = NULL; 433 master->lock.file_priv = NULL; 434 wake_up_interruptible_all(&master->lock.lock_queue); 435 } 436 mutex_unlock(&dev->struct_mutex); 437 438 if (file_priv->minor->master == file_priv->master) { 439 /* drop the reference held my the minor */ 440 if (dev->driver->master_drop) 441 dev->driver->master_drop(dev, file_priv, true); 442 drm_master_put(&file_priv->minor->master); 443 } 444 } 445 446 /* drop the master reference held by the file priv */ 447 if (file_priv->master) 448 drm_master_put(&file_priv->master); 449 file_priv->is_master = 0; 450 mutex_unlock(&dev->master_mutex); 451 452 if (dev->driver->postclose) 453 dev->driver->postclose(dev, file_priv); 454 455 456 if (drm_core_check_feature(dev, DRIVER_PRIME)) 457 drm_prime_destroy_file_private(&file_priv->prime); 458 459 WARN_ON(!list_empty(&file_priv->event_list)); 460 461 put_pid(file_priv->pid); 462 kfree(file_priv); 463 464 /* ======================================================== 465 * End inline drm_release 466 */ 467 468 if (!--dev->open_count) { 469 retcode = drm_lastclose(dev); 470 if (drm_device_is_unplugged(dev)) 471 drm_put_dev(dev); 472 } 473 mutex_unlock(&drm_global_mutex); 474 475 drm_minor_release(minor); 476 477 return retcode; 478} 479EXPORT_SYMBOL(drm_release); 480 481ssize_t drm_read(struct file *filp, char __user *buffer, 482 size_t count, loff_t *offset) 483{ 484 struct drm_file *file_priv = filp->private_data; 485 struct drm_device *dev = file_priv->minor->dev; 486 ssize_t ret = 0; 487 488 if (!access_ok(VERIFY_WRITE, buffer, count)) 489 return -EFAULT; 490 491 spin_lock_irq(&dev->event_lock); 492 for (;;) { 493 if (list_empty(&file_priv->event_list)) { 494 if (ret) 495 break; 496 497 if (filp->f_flags & O_NONBLOCK) { 498 ret = -EAGAIN; 499 break; 500 } 501 502 spin_unlock_irq(&dev->event_lock); 503 ret = wait_event_interruptible(file_priv->event_wait, 504 !list_empty(&file_priv->event_list)); 505 spin_lock_irq(&dev->event_lock); 506 if (ret < 0) 507 break; 508 509 ret = 0; 510 } else { 511 struct drm_pending_event *e; 512 513 e = list_first_entry(&file_priv->event_list, 514 struct drm_pending_event, link); 515 if (e->event->length + ret > count) 516 break; 517 518 if (__copy_to_user_inatomic(buffer + ret, 519 e->event, e->event->length)) { 520 if (ret == 0) 521 ret = -EFAULT; 522 break; 523 } 524 525 file_priv->event_space += e->event->length; 526 ret += e->event->length; 527 list_del(&e->link); 528 e->destroy(e); 529 } 530 } 531 spin_unlock_irq(&dev->event_lock); 532 533 return ret; 534} 535EXPORT_SYMBOL(drm_read); 536 537unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) 538{ 539 struct drm_file *file_priv = filp->private_data; 540 unsigned int mask = 0; 541 542 poll_wait(filp, &file_priv->event_wait, wait); 543 544 if (!list_empty(&file_priv->event_list)) 545 mask |= POLLIN | POLLRDNORM; 546 547 return mask; 548} 549EXPORT_SYMBOL(drm_poll); 550