1/*
   2 * \author Rickard E. (Rik) Faith <faith@valinux.com>
   3 * \author Daryll Strauss <daryll@valinux.com>
   4 * \author Gareth Hughes <gareth@valinux.com>
   5 */
   6
   7/*
   8 * Created: Mon Jan  4 08:58:31 1999 by faith@valinux.com
   9 *
  10 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
  11 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
  12 * All Rights Reserved.
  13 *
  14 * Permission is hereby granted, free of charge, to any person obtaining a
  15 * copy of this software and associated documentation files (the "Software"),
  16 * to deal in the Software without restriction, including without limitation
  17 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  18 * and/or sell copies of the Software, and to permit persons to whom the
  19 * Software is furnished to do so, subject to the following conditions:
  20 *
  21 * The above copyright notice and this permission notice (including the next
  22 * paragraph) shall be included in all copies or substantial portions of the
  23 * Software.
  24 *
  25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  26 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  28 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  29 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  30 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  31 * OTHER DEALINGS IN THE SOFTWARE.
  32 */
  33
  34#include <linux/anon_inodes.h>
  35#include <linux/dma-fence.h>
  36#include <linux/file.h>
  37#include <linux/module.h>
  38#include <linux/pci.h>
  39#include <linux/poll.h>
  40#include <linux/slab.h>
  41
  42#include <drm/drm_client.h>
  43#include <drm/drm_drv.h>
  44#include <drm/drm_file.h>
  45#include <drm/drm_print.h>
  46
  47#include "drm_crtc_internal.h"
  48#include "drm_internal.h"
  49#include "drm_legacy.h"
  50
  51#if defined(CONFIG_MMU) && defined(CONFIG_TRANSPARENT_HUGEPAGE)
  52#include <uapi/asm/mman.h>
  53#include <drm/drm_vma_manager.h>
  54#endif
  55
  56/* from BKL pushdown */
  57DEFINE_MUTEX(drm_global_mutex);
  58
  59bool drm_dev_needs_global_mutex(struct drm_device *dev)
  60{
  61	/*
  62	 * Legacy drivers rely on all kinds of BKL locking semantics, don't
  63	 * bother. They also still need BKL locking for their ioctls, so better
  64	 * safe than sorry.
  65	 */
  66	if (drm_core_check_feature(dev, DRIVER_LEGACY))
  67		return true;
  68
  69	/*
  70	 * The deprecated ->load callback must be called after the driver is
  71	 * already registered. This means such drivers rely on the BKL to make
  72	 * sure an open can't proceed until the driver is actually fully set up.
  73	 * Similar hilarity holds for the unload callback.
  74	 */
  75	if (dev->driver->load || dev->driver->unload)
  76		return true;
  77
  78	/*
  79	 * Drivers with the lastclose callback assume that it's synchronized
  80	 * against concurrent opens, which again needs the BKL. The proper fix
  81	 * is to use the drm_client infrastructure with proper locking for each
  82	 * client.
  83	 */
  84	if (dev->driver->lastclose)
  85		return true;
  86
  87	return false;
  88}
  89
  90/**
  91 * DOC: file operations
  92 *
  93 * Drivers must define the file operations structure that forms the DRM
  94 * userspace API entry point, even though most of those operations are
  95 * implemented in the DRM core. The resulting &struct file_operations must be
  96 * stored in the &drm_driver.fops field. The mandatory functions are drm_open(),
  97 * drm_read(), drm_ioctl() and drm_compat_ioctl() if CONFIG_COMPAT is enabled
  98 * Note that drm_compat_ioctl will be NULL if CONFIG_COMPAT=n, so there's no
  99 * need to sprinkle #ifdef into the code. Drivers which implement private ioctls
 100 * that require 32/64 bit compatibility support must provide their own
 101 * &file_operations.compat_ioctl handler that processes private ioctls and calls
 102 * drm_compat_ioctl() for core ioctls.
 103 *
 104 * In addition drm_read() and drm_poll() provide support for DRM events. DRM
 105 * events are a generic and extensible means to send asynchronous events to
 106 * userspace through the file descriptor. They are used to send vblank event and
 107 * page flip completions by the KMS API. But drivers can also use it for their
 108 * own needs, e.g. to signal completion of rendering.
 109 *
 110 * For the driver-side event interface see drm_event_reserve_init() and
 111 * drm_send_event() as the main starting points.
 112 *
 113 * The memory mapping implementation will vary depending on how the driver
 114 * manages memory. Legacy drivers will use the deprecated drm_legacy_mmap()
 115 * function, modern drivers should use one of the provided memory-manager
 116 * specific implementations. For GEM-based drivers this is drm_gem_mmap(), and
 117 * for drivers which use the CMA GEM helpers it's drm_gem_cma_mmap().
 118 *
 119 * No other file operations are supported by the DRM userspace API. Overall the
 120 * following is an example &file_operations structure::
 121 *
 122 *     static const example_drm_fops = {
 123 *             .owner = THIS_MODULE,
 124 *             .open = drm_open,
 125 *             .release = drm_release,
 126 *             .unlocked_ioctl = drm_ioctl,
 127 *             .compat_ioctl = drm_compat_ioctl, // NULL if CONFIG_COMPAT=n
 128 *             .poll = drm_poll,
 129 *             .read = drm_read,
 130 *             .llseek = no_llseek,
 131 *             .mmap = drm_gem_mmap,
 132 *     };
 133 *
 134 * For plain GEM based drivers there is the DEFINE_DRM_GEM_FOPS() macro, and for
 135 * CMA based drivers there is the DEFINE_DRM_GEM_CMA_FOPS() macro to make this
 136 * simpler.
 137 *
 138 * The driver's &file_operations must be stored in &drm_driver.fops.
 139 *
 140 * For driver-private IOCTL handling see the more detailed discussion in
 141 * :ref:`IOCTL support in the userland interfaces chapter<drm_driver_ioctl>`.
 142 */
 143
 144/**
 145 * drm_file_alloc - allocate file context
 146 * @minor: minor to allocate on
 147 *
 148 * This allocates a new DRM file context. It is not linked into any context and
 149 * can be used by the caller freely. Note that the context keeps a pointer to
 150 * @minor, so it must be freed before @minor is.
 151 *
 152 * RETURNS:
 153 * Pointer to newly allocated context, ERR_PTR on failure.
 154 */
 155struct drm_file *drm_file_alloc(struct drm_minor *minor)
 156{
 157	struct drm_device *dev = minor->dev;
 158	struct drm_file *file;
 159	int ret;
 160
 161	file = kzalloc(sizeof(*file), GFP_KERNEL);
 162	if (!file)
 163		return ERR_PTR(-ENOMEM);
 164
 165	file->pid = get_pid(task_pid(current));
 166	file->minor = minor;
 167
 168	/* for compatibility root is always authenticated */
 169	file->authenticated = capable(CAP_SYS_ADMIN);
 170
 171	INIT_LIST_HEAD(&file->lhead);
 172	INIT_LIST_HEAD(&file->fbs);
 173	mutex_init(&file->fbs_lock);
 174	INIT_LIST_HEAD(&file->blobs);
 175	INIT_LIST_HEAD(&file->pending_event_list);
 176	INIT_LIST_HEAD(&file->event_list);
 177	init_waitqueue_head(&file->event_wait);
 178	file->event_space = 4096; /* set aside 4k for event buffer */
 179
 
 180	mutex_init(&file->event_read_lock);
 181
 182	if (drm_core_check_feature(dev, DRIVER_GEM))
 183		drm_gem_open(dev, file);
 184
 185	if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 186		drm_syncobj_open(file);
 187
 188	drm_prime_init_file_private(&file->prime);
 189
 190	if (dev->driver->open) {
 191		ret = dev->driver->open(dev, file);
 192		if (ret < 0)
 193			goto out_prime_destroy;
 194	}
 195
 196	return file;
 197
 198out_prime_destroy:
 199	drm_prime_destroy_file_private(&file->prime);
 200	if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 201		drm_syncobj_release(file);
 202	if (drm_core_check_feature(dev, DRIVER_GEM))
 203		drm_gem_release(dev, file);
 204	put_pid(file->pid);
 205	kfree(file);
 206
 207	return ERR_PTR(ret);
 208}
 209
 210static void drm_events_release(struct drm_file *file_priv)
 211{
 212	struct drm_device *dev = file_priv->minor->dev;
 213	struct drm_pending_event *e, *et;
 214	unsigned long flags;
 215
 216	spin_lock_irqsave(&dev->event_lock, flags);
 217
 218	/* Unlink pending events */
 219	list_for_each_entry_safe(e, et, &file_priv->pending_event_list,
 220				 pending_link) {
 221		list_del(&e->pending_link);
 222		e->file_priv = NULL;
 223	}
 224
 225	/* Remove unconsumed events */
 226	list_for_each_entry_safe(e, et, &file_priv->event_list, link) {
 227		list_del(&e->link);
 228		kfree(e);
 229	}
 230
 231	spin_unlock_irqrestore(&dev->event_lock, flags);
 232}
 233
 234/**
 235 * drm_file_free - free file context
 236 * @file: context to free, or NULL
 237 *
 238 * This destroys and deallocates a DRM file context previously allocated via
 239 * drm_file_alloc(). The caller must make sure to unlink it from any contexts
 240 * before calling this.
 241 *
 242 * If NULL is passed, this is a no-op.
 243 *
 244 * RETURNS:
 245 * 0 on success, or error code on failure.
 246 */
 247void drm_file_free(struct drm_file *file)
 248{
 249	struct drm_device *dev;
 250
 251	if (!file)
 252		return;
 253
 254	dev = file->minor->dev;
 255
 256	DRM_DEBUG("comm=\"%s\", pid=%d, dev=0x%lx, open_count=%d\n",
 257		  current->comm, task_pid_nr(current),
 258		  (long)old_encode_dev(file->minor->kdev->devt),
 259		  atomic_read(&dev->open_count));
 260
 
 261	if (drm_core_check_feature(dev, DRIVER_LEGACY) &&
 262	    dev->driver->preclose)
 263		dev->driver->preclose(dev, file);
 
 264
 265	if (drm_core_check_feature(dev, DRIVER_LEGACY))
 266		drm_legacy_lock_release(dev, file->filp);
 267
 268	if (drm_core_check_feature(dev, DRIVER_HAVE_DMA))
 269		drm_legacy_reclaim_buffers(dev, file);
 270
 271	drm_events_release(file);
 272
 273	if (drm_core_check_feature(dev, DRIVER_MODESET)) {
 274		drm_fb_release(file);
 275		drm_property_destroy_user_blobs(dev, file);
 276	}
 277
 278	if (drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 279		drm_syncobj_release(file);
 280
 281	if (drm_core_check_feature(dev, DRIVER_GEM))
 282		drm_gem_release(dev, file);
 283
 284	drm_legacy_ctxbitmap_flush(dev, file);
 285
 286	if (drm_is_primary_client(file))
 287		drm_master_release(file);
 288
 289	if (dev->driver->postclose)
 290		dev->driver->postclose(dev, file);
 291
 292	drm_prime_destroy_file_private(&file->prime);
 293
 294	WARN_ON(!list_empty(&file->event_list));
 295
 296	put_pid(file->pid);
 297	kfree(file);
 298}
 299
 300static void drm_close_helper(struct file *filp)
 301{
 302	struct drm_file *file_priv = filp->private_data;
 303	struct drm_device *dev = file_priv->minor->dev;
 304
 305	mutex_lock(&dev->filelist_mutex);
 306	list_del(&file_priv->lhead);
 307	mutex_unlock(&dev->filelist_mutex);
 308
 309	drm_file_free(file_priv);
 310}
 311
 312/*
 313 * Check whether DRI will run on this CPU.
 314 *
 315 * \return non-zero if the DRI will run on this CPU, or zero otherwise.
 316 */
 317static int drm_cpu_valid(void)
 318{
 319#if defined(__sparc__) && !defined(__sparc_v9__)
 320	return 0;		/* No cmpxchg before v9 sparc. */
 321#endif
 322	return 1;
 323}
 324
 325/*
 326 * Called whenever a process opens a drm node
 327 *
 328 * \param filp file pointer.
 329 * \param minor acquired minor-object.
 330 * \return zero on success or a negative number on failure.
 331 *
 332 * Creates and initializes a drm_file structure for the file private data in \p
 333 * filp and add it into the double linked list in \p dev.
 334 */
 335static int drm_open_helper(struct file *filp, struct drm_minor *minor)
 336{
 337	struct drm_device *dev = minor->dev;
 338	struct drm_file *priv;
 339	int ret;
 340
 341	if (filp->f_flags & O_EXCL)
 342		return -EBUSY;	/* No exclusive opens */
 343	if (!drm_cpu_valid())
 344		return -EINVAL;
 345	if (dev->switch_power_state != DRM_SWITCH_POWER_ON &&
 346	    dev->switch_power_state != DRM_SWITCH_POWER_DYNAMIC_OFF)
 347		return -EINVAL;
 348
 349	DRM_DEBUG("comm=\"%s\", pid=%d, minor=%d\n", current->comm,
 350		  task_pid_nr(current), minor->index);
 351
 352	priv = drm_file_alloc(minor);
 353	if (IS_ERR(priv))
 354		return PTR_ERR(priv);
 355
 356	if (drm_is_primary_client(priv)) {
 357		ret = drm_master_open(priv);
 358		if (ret) {
 359			drm_file_free(priv);
 360			return ret;
 361		}
 362	}
 363
 364	filp->private_data = priv;
 365	filp->f_mode |= FMODE_UNSIGNED_OFFSET;
 366	priv->filp = filp;
 367
 368	mutex_lock(&dev->filelist_mutex);
 369	list_add(&priv->lhead, &dev->filelist);
 370	mutex_unlock(&dev->filelist_mutex);
 371
 
 372#ifdef __alpha__
 373	/*
 374	 * Default the hose
 375	 */
 376	if (!dev->hose) {
 377		struct pci_dev *pci_dev;
 378
 379		pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL);
 380		if (pci_dev) {
 381			dev->hose = pci_dev->sysdata;
 382			pci_dev_put(pci_dev);
 383		}
 384		if (!dev->hose) {
 385			struct pci_bus *b = list_entry(pci_root_buses.next,
 386				struct pci_bus, node);
 387			if (b)
 388				dev->hose = b->sysdata;
 389		}
 390	}
 391#endif
 
 392
 393	return 0;
 394}
 395
 396/**
 397 * drm_open - open method for DRM file
 398 * @inode: device inode
 399 * @filp: file pointer.
 400 *
 401 * This function must be used by drivers as their &file_operations.open method.
 402 * It looks up the correct DRM device and instantiates all the per-file
 403 * resources for it. It also calls the &drm_driver.open driver callback.
 404 *
 405 * RETURNS:
 406 *
 407 * 0 on success or negative errno value on falure.
 408 */
 409int drm_open(struct inode *inode, struct file *filp)
 410{
 411	struct drm_device *dev;
 412	struct drm_minor *minor;
 413	int retcode;
 414	int need_setup = 0;
 415
 416	minor = drm_minor_acquire(iminor(inode));
 417	if (IS_ERR(minor))
 418		return PTR_ERR(minor);
 419
 420	dev = minor->dev;
 421	if (drm_dev_needs_global_mutex(dev))
 422		mutex_lock(&drm_global_mutex);
 423
 424	if (!atomic_fetch_inc(&dev->open_count))
 425		need_setup = 1;
 426
 427	/* share address_space across all char-devs of a single device */
 428	filp->f_mapping = dev->anon_inode->i_mapping;
 429
 430	retcode = drm_open_helper(filp, minor);
 431	if (retcode)
 432		goto err_undo;
 433	if (need_setup) {
 434		retcode = drm_legacy_setup(dev);
 435		if (retcode) {
 436			drm_close_helper(filp);
 437			goto err_undo;
 438		}
 439	}
 440
 441	if (drm_dev_needs_global_mutex(dev))
 442		mutex_unlock(&drm_global_mutex);
 443
 444	return 0;
 445
 446err_undo:
 447	atomic_dec(&dev->open_count);
 448	if (drm_dev_needs_global_mutex(dev))
 449		mutex_unlock(&drm_global_mutex);
 450	drm_minor_release(minor);
 451	return retcode;
 452}
 453EXPORT_SYMBOL(drm_open);
 454
 455void drm_lastclose(struct drm_device * dev)
 456{
 457	DRM_DEBUG("\n");
 458
 459	if (dev->driver->lastclose)
 460		dev->driver->lastclose(dev);
 461	DRM_DEBUG("driver lastclose completed\n");
 462
 463	if (drm_core_check_feature(dev, DRIVER_LEGACY))
 464		drm_legacy_dev_reinit(dev);
 465
 466	drm_client_dev_restore(dev);
 467}
 468
 469/**
 470 * drm_release - release method for DRM file
 471 * @inode: device inode
 472 * @filp: file pointer.
 473 *
 474 * This function must be used by drivers as their &file_operations.release
 475 * method. It frees any resources associated with the open file, and calls the
 476 * &drm_driver.postclose driver callback. If this is the last open file for the
 477 * DRM device also proceeds to call the &drm_driver.lastclose driver callback.
 478 *
 479 * RETURNS:
 480 *
 481 * Always succeeds and returns 0.
 482 */
 483int drm_release(struct inode *inode, struct file *filp)
 484{
 485	struct drm_file *file_priv = filp->private_data;
 486	struct drm_minor *minor = file_priv->minor;
 487	struct drm_device *dev = minor->dev;
 488
 489	if (drm_dev_needs_global_mutex(dev))
 490		mutex_lock(&drm_global_mutex);
 491
 492	DRM_DEBUG("open_count = %d\n", atomic_read(&dev->open_count));
 493
 494	drm_close_helper(filp);
 495
 496	if (atomic_dec_and_test(&dev->open_count))
 497		drm_lastclose(dev);
 498
 499	if (drm_dev_needs_global_mutex(dev))
 500		mutex_unlock(&drm_global_mutex);
 501
 502	drm_minor_release(minor);
 503
 504	return 0;
 505}
 506EXPORT_SYMBOL(drm_release);
 507
 508/**
 509 * drm_release_noglobal - release method for DRM file
 510 * @inode: device inode
 511 * @filp: file pointer.
 512 *
 513 * This function may be used by drivers as their &file_operations.release
 514 * method. It frees any resources associated with the open file prior to taking
 515 * the drm_global_mutex, which then calls the &drm_driver.postclose driver
 516 * callback. If this is the last open file for the DRM device also proceeds to
 517 * call the &drm_driver.lastclose driver callback.
 518 *
 519 * RETURNS:
 520 *
 521 * Always succeeds and returns 0.
 522 */
 523int drm_release_noglobal(struct inode *inode, struct file *filp)
 524{
 525	struct drm_file *file_priv = filp->private_data;
 526	struct drm_minor *minor = file_priv->minor;
 527	struct drm_device *dev = minor->dev;
 528
 529	drm_close_helper(filp);
 530
 531	if (atomic_dec_and_mutex_lock(&dev->open_count, &drm_global_mutex)) {
 532		drm_lastclose(dev);
 533		mutex_unlock(&drm_global_mutex);
 534	}
 535
 536	drm_minor_release(minor);
 537
 538	return 0;
 539}
 540EXPORT_SYMBOL(drm_release_noglobal);
 541
 542/**
 543 * drm_read - read method for DRM file
 544 * @filp: file pointer
 545 * @buffer: userspace destination pointer for the read
 546 * @count: count in bytes to read
 547 * @offset: offset to read
 548 *
 549 * This function must be used by drivers as their &file_operations.read
 550 * method iff they use DRM events for asynchronous signalling to userspace.
 551 * Since events are used by the KMS API for vblank and page flip completion this
 552 * means all modern display drivers must use it.
 553 *
 554 * @offset is ignored, DRM events are read like a pipe. Therefore drivers also
 555 * must set the &file_operation.llseek to no_llseek(). Polling support is
 556 * provided by drm_poll().
 557 *
 558 * This function will only ever read a full event. Therefore userspace must
 559 * supply a big enough buffer to fit any event to ensure forward progress. Since
 560 * the maximum event space is currently 4K it's recommended to just use that for
 561 * safety.
 562 *
 563 * RETURNS:
 564 *
 565 * Number of bytes read (always aligned to full events, and can be 0) or a
 566 * negative error code on failure.
 567 */
 568ssize_t drm_read(struct file *filp, char __user *buffer,
 569		 size_t count, loff_t *offset)
 570{
 571	struct drm_file *file_priv = filp->private_data;
 572	struct drm_device *dev = file_priv->minor->dev;
 573	ssize_t ret;
 574
 575	ret = mutex_lock_interruptible(&file_priv->event_read_lock);
 576	if (ret)
 577		return ret;
 578
 579	for (;;) {
 580		struct drm_pending_event *e = NULL;
 581
 582		spin_lock_irq(&dev->event_lock);
 583		if (!list_empty(&file_priv->event_list)) {
 584			e = list_first_entry(&file_priv->event_list,
 585					struct drm_pending_event, link);
 586			file_priv->event_space += e->event->length;
 587			list_del(&e->link);
 588		}
 589		spin_unlock_irq(&dev->event_lock);
 590
 591		if (e == NULL) {
 592			if (ret)
 593				break;
 594
 595			if (filp->f_flags & O_NONBLOCK) {
 596				ret = -EAGAIN;
 597				break;
 598			}
 599
 600			mutex_unlock(&file_priv->event_read_lock);
 601			ret = wait_event_interruptible(file_priv->event_wait,
 602						       !list_empty(&file_priv->event_list));
 603			if (ret >= 0)
 604				ret = mutex_lock_interruptible(&file_priv->event_read_lock);
 605			if (ret)
 606				return ret;
 607		} else {
 608			unsigned length = e->event->length;
 609
 610			if (length > count - ret) {
 611put_back_event:
 612				spin_lock_irq(&dev->event_lock);
 613				file_priv->event_space -= length;
 614				list_add(&e->link, &file_priv->event_list);
 615				spin_unlock_irq(&dev->event_lock);
 616				wake_up_interruptible_poll(&file_priv->event_wait,
 617					EPOLLIN | EPOLLRDNORM);
 618				break;
 619			}
 620
 621			if (copy_to_user(buffer + ret, e->event, length)) {
 622				if (ret == 0)
 623					ret = -EFAULT;
 624				goto put_back_event;
 625			}
 626
 627			ret += length;
 628			kfree(e);
 629		}
 630	}
 631	mutex_unlock(&file_priv->event_read_lock);
 632
 633	return ret;
 634}
 635EXPORT_SYMBOL(drm_read);
 636
 637/**
 638 * drm_poll - poll method for DRM file
 639 * @filp: file pointer
 640 * @wait: poll waiter table
 641 *
 642 * This function must be used by drivers as their &file_operations.read method
 643 * iff they use DRM events for asynchronous signalling to userspace.  Since
 644 * events are used by the KMS API for vblank and page flip completion this means
 645 * all modern display drivers must use it.
 646 *
 647 * See also drm_read().
 648 *
 649 * RETURNS:
 650 *
 651 * Mask of POLL flags indicating the current status of the file.
 652 */
 653__poll_t drm_poll(struct file *filp, struct poll_table_struct *wait)
 654{
 655	struct drm_file *file_priv = filp->private_data;
 656	__poll_t mask = 0;
 657
 658	poll_wait(filp, &file_priv->event_wait, wait);
 659
 660	if (!list_empty(&file_priv->event_list))
 661		mask |= EPOLLIN | EPOLLRDNORM;
 662
 663	return mask;
 664}
 665EXPORT_SYMBOL(drm_poll);
 666
 667/**
 668 * drm_event_reserve_init_locked - init a DRM event and reserve space for it
 669 * @dev: DRM device
 670 * @file_priv: DRM file private data
 671 * @p: tracking structure for the pending event
 672 * @e: actual event data to deliver to userspace
 673 *
 674 * This function prepares the passed in event for eventual delivery. If the event
 675 * doesn't get delivered (because the IOCTL fails later on, before queuing up
 676 * anything) then the even must be cancelled and freed using
 677 * drm_event_cancel_free(). Successfully initialized events should be sent out
 678 * using drm_send_event() or drm_send_event_locked() to signal completion of the
 679 * asynchronous event to userspace.
 680 *
 681 * If callers embedded @p into a larger structure it must be allocated with
 682 * kmalloc and @p must be the first member element.
 683 *
 684 * This is the locked version of drm_event_reserve_init() for callers which
 685 * already hold &drm_device.event_lock.
 686 *
 687 * RETURNS:
 688 *
 689 * 0 on success or a negative error code on failure.
 690 */
 691int drm_event_reserve_init_locked(struct drm_device *dev,
 692				  struct drm_file *file_priv,
 693				  struct drm_pending_event *p,
 694				  struct drm_event *e)
 695{
 696	if (file_priv->event_space < e->length)
 697		return -ENOMEM;
 698
 699	file_priv->event_space -= e->length;
 700
 701	p->event = e;
 702	list_add(&p->pending_link, &file_priv->pending_event_list);
 703	p->file_priv = file_priv;
 704
 705	return 0;
 706}
 707EXPORT_SYMBOL(drm_event_reserve_init_locked);
 708
 709/**
 710 * drm_event_reserve_init - init a DRM event and reserve space for it
 711 * @dev: DRM device
 712 * @file_priv: DRM file private data
 713 * @p: tracking structure for the pending event
 714 * @e: actual event data to deliver to userspace
 715 *
 716 * This function prepares the passed in event for eventual delivery. If the event
 717 * doesn't get delivered (because the IOCTL fails later on, before queuing up
 718 * anything) then the even must be cancelled and freed using
 719 * drm_event_cancel_free(). Successfully initialized events should be sent out
 720 * using drm_send_event() or drm_send_event_locked() to signal completion of the
 721 * asynchronous event to userspace.
 722 *
 723 * If callers embedded @p into a larger structure it must be allocated with
 724 * kmalloc and @p must be the first member element.
 725 *
 726 * Callers which already hold &drm_device.event_lock should use
 727 * drm_event_reserve_init_locked() instead.
 728 *
 729 * RETURNS:
 730 *
 731 * 0 on success or a negative error code on failure.
 732 */
 733int drm_event_reserve_init(struct drm_device *dev,
 734			   struct drm_file *file_priv,
 735			   struct drm_pending_event *p,
 736			   struct drm_event *e)
 737{
 738	unsigned long flags;
 739	int ret;
 740
 741	spin_lock_irqsave(&dev->event_lock, flags);
 742	ret = drm_event_reserve_init_locked(dev, file_priv, p, e);
 743	spin_unlock_irqrestore(&dev->event_lock, flags);
 744
 745	return ret;
 746}
 747EXPORT_SYMBOL(drm_event_reserve_init);
 748
 749/**
 750 * drm_event_cancel_free - free a DRM event and release its space
 751 * @dev: DRM device
 752 * @p: tracking structure for the pending event
 753 *
 754 * This function frees the event @p initialized with drm_event_reserve_init()
 755 * and releases any allocated space. It is used to cancel an event when the
 756 * nonblocking operation could not be submitted and needed to be aborted.
 757 */
 758void drm_event_cancel_free(struct drm_device *dev,
 759			   struct drm_pending_event *p)
 760{
 761	unsigned long flags;
 762
 763	spin_lock_irqsave(&dev->event_lock, flags);
 764	if (p->file_priv) {
 765		p->file_priv->event_space += p->event->length;
 766		list_del(&p->pending_link);
 767	}
 768	spin_unlock_irqrestore(&dev->event_lock, flags);
 769
 770	if (p->fence)
 771		dma_fence_put(p->fence);
 772
 773	kfree(p);
 774}
 775EXPORT_SYMBOL(drm_event_cancel_free);
 776
 777/**
 778 * drm_send_event_locked - send DRM event to file descriptor
 779 * @dev: DRM device
 780 * @e: DRM event to deliver
 781 *
 782 * This function sends the event @e, initialized with drm_event_reserve_init(),
 783 * to its associated userspace DRM file. Callers must already hold
 784 * &drm_device.event_lock, see drm_send_event() for the unlocked version.
 785 *
 786 * Note that the core will take care of unlinking and disarming events when the
 787 * corresponding DRM file is closed. Drivers need not worry about whether the
 788 * DRM file for this event still exists and can call this function upon
 789 * completion of the asynchronous work unconditionally.
 790 */
 791void drm_send_event_locked(struct drm_device *dev, struct drm_pending_event *e)
 792{
 793	assert_spin_locked(&dev->event_lock);
 794
 795	if (e->completion) {
 796		complete_all(e->completion);
 797		e->completion_release(e->completion);
 798		e->completion = NULL;
 799	}
 800
 801	if (e->fence) {
 802		dma_fence_signal(e->fence);
 
 
 
 803		dma_fence_put(e->fence);
 804	}
 805
 806	if (!e->file_priv) {
 807		kfree(e);
 808		return;
 809	}
 810
 811	list_del(&e->pending_link);
 812	list_add_tail(&e->link,
 813		      &e->file_priv->event_list);
 814	wake_up_interruptible_poll(&e->file_priv->event_wait,
 815		EPOLLIN | EPOLLRDNORM);
 816}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 817EXPORT_SYMBOL(drm_send_event_locked);
 818
 819/**
 820 * drm_send_event - send DRM event to file descriptor
 821 * @dev: DRM device
 822 * @e: DRM event to deliver
 823 *
 824 * This function sends the event @e, initialized with drm_event_reserve_init(),
 825 * to its associated userspace DRM file. This function acquires
 826 * &drm_device.event_lock, see drm_send_event_locked() for callers which already
 827 * hold this lock.
 828 *
 829 * Note that the core will take care of unlinking and disarming events when the
 830 * corresponding DRM file is closed. Drivers need not worry about whether the
 831 * DRM file for this event still exists and can call this function upon
 832 * completion of the asynchronous work unconditionally.
 833 */
 834void drm_send_event(struct drm_device *dev, struct drm_pending_event *e)
 835{
 836	unsigned long irqflags;
 837
 838	spin_lock_irqsave(&dev->event_lock, irqflags);
 839	drm_send_event_locked(dev, e);
 840	spin_unlock_irqrestore(&dev->event_lock, irqflags);
 841}
 842EXPORT_SYMBOL(drm_send_event);
 843
 844/**
 845 * mock_drm_getfile - Create a new struct file for the drm device
 846 * @minor: drm minor to wrap (e.g. #drm_device.primary)
 847 * @flags: file creation mode (O_RDWR etc)
 848 *
 849 * This create a new struct file that wraps a DRM file context around a
 850 * DRM minor. This mimicks userspace opening e.g. /dev/dri/card0, but without
 851 * invoking userspace. The struct file may be operated on using its f_op
 852 * (the drm_device.driver.fops) to mimick userspace operations, or be supplied
 853 * to userspace facing functions as an internal/anonymous client.
 854 *
 855 * RETURNS:
 856 * Pointer to newly created struct file, ERR_PTR on failure.
 857 */
 858struct file *mock_drm_getfile(struct drm_minor *minor, unsigned int flags)
 859{
 860	struct drm_device *dev = minor->dev;
 861	struct drm_file *priv;
 862	struct file *file;
 863
 864	priv = drm_file_alloc(minor);
 865	if (IS_ERR(priv))
 866		return ERR_CAST(priv);
 867
 868	file = anon_inode_getfile("drm", dev->driver->fops, priv, flags);
 869	if (IS_ERR(file)) {
 870		drm_file_free(priv);
 871		return file;
 872	}
 873
 874	/* Everyone shares a single global address space */
 875	file->f_mapping = dev->anon_inode->i_mapping;
 876
 877	drm_dev_get(dev);
 878	priv->filp = file;
 879
 880	return file;
 881}
 882EXPORT_SYMBOL_FOR_TESTS_ONLY(mock_drm_getfile);
 883
 884#ifdef CONFIG_MMU
 885#ifdef CONFIG_TRANSPARENT_HUGEPAGE
 886/*
 887 * drm_addr_inflate() attempts to construct an aligned area by inflating
 888 * the area size and skipping the unaligned start of the area.
 889 * adapted from shmem_get_unmapped_area()
 890 */
 891static unsigned long drm_addr_inflate(unsigned long addr,
 892				      unsigned long len,
 893				      unsigned long pgoff,
 894				      unsigned long flags,
 895				      unsigned long huge_size)
 896{
 897	unsigned long offset, inflated_len;
 898	unsigned long inflated_addr;
 899	unsigned long inflated_offset;
 900
 901	offset = (pgoff << PAGE_SHIFT) & (huge_size - 1);
 902	if (offset && offset + len < 2 * huge_size)
 903		return addr;
 904	if ((addr & (huge_size - 1)) == offset)
 905		return addr;
 906
 907	inflated_len = len + huge_size - PAGE_SIZE;
 908	if (inflated_len > TASK_SIZE)
 909		return addr;
 910	if (inflated_len < len)
 911		return addr;
 912
 913	inflated_addr = current->mm->get_unmapped_area(NULL, 0, inflated_len,
 914						       0, flags);
 915	if (IS_ERR_VALUE(inflated_addr))
 916		return addr;
 917	if (inflated_addr & ~PAGE_MASK)
 918		return addr;
 919
 920	inflated_offset = inflated_addr & (huge_size - 1);
 921	inflated_addr += offset - inflated_offset;
 922	if (inflated_offset > offset)
 923		inflated_addr += huge_size;
 924
 925	if (inflated_addr > TASK_SIZE - len)
 926		return addr;
 927
 928	return inflated_addr;
 929}
 930
 931/**
 932 * drm_get_unmapped_area() - Get an unused user-space virtual memory area
 933 * suitable for huge page table entries.
 934 * @file: The struct file representing the address space being mmap()'d.
 935 * @uaddr: Start address suggested by user-space.
 936 * @len: Length of the area.
 937 * @pgoff: The page offset into the address space.
 938 * @flags: mmap flags
 939 * @mgr: The address space manager used by the drm driver. This argument can
 940 * probably be removed at some point when all drivers use the same
 941 * address space manager.
 942 *
 943 * This function attempts to find an unused user-space virtual memory area
 944 * that can accommodate the size we want to map, and that is properly
 945 * aligned to facilitate huge page table entries matching actual
 946 * huge pages or huge page aligned memory in buffer objects. Buffer objects
 947 * are assumed to start at huge page boundary pfns (io memory) or be
 948 * populated by huge pages aligned to the start of the buffer object
 949 * (system- or coherent memory). Adapted from shmem_get_unmapped_area.
 950 *
 951 * Return: aligned user-space address.
 952 */
 953unsigned long drm_get_unmapped_area(struct file *file,
 954				    unsigned long uaddr, unsigned long len,
 955				    unsigned long pgoff, unsigned long flags,
 956				    struct drm_vma_offset_manager *mgr)
 957{
 958	unsigned long addr;
 959	unsigned long inflated_addr;
 960	struct drm_vma_offset_node *node;
 961
 962	if (len > TASK_SIZE)
 963		return -ENOMEM;
 964
 965	/*
 966	 * @pgoff is the file page-offset the huge page boundaries of
 967	 * which typically aligns to physical address huge page boundaries.
 968	 * That's not true for DRM, however, where physical address huge
 969	 * page boundaries instead are aligned with the offset from
 970	 * buffer object start. So adjust @pgoff to be the offset from
 971	 * buffer object start.
 972	 */
 973	drm_vma_offset_lock_lookup(mgr);
 974	node = drm_vma_offset_lookup_locked(mgr, pgoff, 1);
 975	if (node)
 976		pgoff -= node->vm_node.start;
 977	drm_vma_offset_unlock_lookup(mgr);
 978
 979	addr = current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
 980	if (IS_ERR_VALUE(addr))
 981		return addr;
 982	if (addr & ~PAGE_MASK)
 983		return addr;
 984	if (addr > TASK_SIZE - len)
 985		return addr;
 986
 987	if (len < HPAGE_PMD_SIZE)
 988		return addr;
 989	if (flags & MAP_FIXED)
 990		return addr;
 991	/*
 992	 * Our priority is to support MAP_SHARED mapped hugely;
 993	 * and support MAP_PRIVATE mapped hugely too, until it is COWed.
 994	 * But if caller specified an address hint, respect that as before.
 995	 */
 996	if (uaddr)
 997		return addr;
 998
 999	inflated_addr = drm_addr_inflate(addr, len, pgoff, flags,
1000					 HPAGE_PMD_SIZE);
1001
1002	if (IS_ENABLED(CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD) &&
1003	    len >= HPAGE_PUD_SIZE)
1004		inflated_addr = drm_addr_inflate(inflated_addr, len, pgoff,
1005						 flags, HPAGE_PUD_SIZE);
1006	return inflated_addr;
1007}
1008#else /* CONFIG_TRANSPARENT_HUGEPAGE */
1009unsigned long drm_get_unmapped_area(struct file *file,
1010				    unsigned long uaddr, unsigned long len,
1011				    unsigned long pgoff, unsigned long flags,
1012				    struct drm_vma_offset_manager *mgr)
1013{
1014	return current->mm->get_unmapped_area(file, uaddr, len, pgoff, flags);
1015}
1016#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
1017EXPORT_SYMBOL_GPL(drm_get_unmapped_area);
1018#endif /* CONFIG_MMU */