| 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() */ |
| 43 | DEFINE_MUTEX(drm_global_mutex); |
| 44 | EXPORT_SYMBOL(drm_global_mutex); |
| 45 | |
| 46 | static int drm_open_helper(struct inode *inode, struct file *filp, |
| 47 | struct drm_device * dev); |
| 48 | |
| 49 | static 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->context_flag = 0; |
| 79 | dev->interrupt_flag = 0; |
| 80 | dev->dma_flag = 0; |
| 81 | dev->last_context = 0; |
| 82 | dev->last_switch = 0; |
| 83 | dev->last_checked = 0; |
| 84 | init_waitqueue_head(&dev->context_wait); |
| 85 | dev->if_version = 0; |
| 86 | |
| 87 | dev->ctx_start = 0; |
| 88 | dev->lck_start = 0; |
| 89 | |
| 90 | dev->buf_async = NULL; |
| 91 | init_waitqueue_head(&dev->buf_readers); |
| 92 | init_waitqueue_head(&dev->buf_writers); |
| 93 | |
| 94 | DRM_DEBUG("\n"); |
| 95 | |
| 96 | /* |
| 97 | * The kernel's context could be created here, but is now created |
| 98 | * in drm_dma_enqueue. This is more resource-efficient for |
| 99 | * hardware that does not do DMA, but may mean that |
| 100 | * drm_select_queue fails between the time the interrupt is |
| 101 | * initialized and the time the queues are initialized. |
| 102 | */ |
| 103 | |
| 104 | return 0; |
| 105 | } |
| 106 | |
| 107 | /** |
| 108 | * Open file. |
| 109 | * |
| 110 | * \param inode device inode |
| 111 | * \param filp file pointer. |
| 112 | * \return zero on success or a negative number on failure. |
| 113 | * |
| 114 | * Searches the DRM device with the same minor number, calls open_helper(), and |
| 115 | * increments the device open count. If the open count was previous at zero, |
| 116 | * i.e., it's the first that the device is open, then calls setup(). |
| 117 | */ |
| 118 | int drm_open(struct inode *inode, struct file *filp) |
| 119 | { |
| 120 | struct drm_device *dev = NULL; |
| 121 | int minor_id = iminor(inode); |
| 122 | struct drm_minor *minor; |
| 123 | int retcode = 0; |
| 124 | |
| 125 | minor = idr_find(&drm_minors_idr, minor_id); |
| 126 | if (!minor) |
| 127 | return -ENODEV; |
| 128 | |
| 129 | if (!(dev = minor->dev)) |
| 130 | return -ENODEV; |
| 131 | |
| 132 | if (drm_device_is_unplugged(dev)) |
| 133 | return -ENODEV; |
| 134 | |
| 135 | retcode = drm_open_helper(inode, filp, dev); |
| 136 | if (!retcode) { |
| 137 | atomic_inc(&dev->counts[_DRM_STAT_OPENS]); |
| 138 | if (!dev->open_count++) |
| 139 | retcode = drm_setup(dev); |
| 140 | } |
| 141 | if (!retcode) { |
| 142 | mutex_lock(&dev->struct_mutex); |
| 143 | if (dev->dev_mapping == NULL) |
| 144 | dev->dev_mapping = &inode->i_data; |
| 145 | /* ihold ensures nobody can remove inode with our i_data */ |
| 146 | ihold(container_of(dev->dev_mapping, struct inode, i_data)); |
| 147 | inode->i_mapping = dev->dev_mapping; |
| 148 | filp->f_mapping = dev->dev_mapping; |
| 149 | mutex_unlock(&dev->struct_mutex); |
| 150 | } |
| 151 | |
| 152 | return retcode; |
| 153 | } |
| 154 | EXPORT_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 | */ |
| 165 | int 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 | mutex_lock(&drm_global_mutex); |
| 176 | minor = idr_find(&drm_minors_idr, minor_id); |
| 177 | if (!minor) |
| 178 | goto out; |
| 179 | |
| 180 | if (!(dev = minor->dev)) |
| 181 | goto out; |
| 182 | |
| 183 | if (drm_device_is_unplugged(dev)) |
| 184 | goto out; |
| 185 | |
| 186 | old_fops = filp->f_op; |
| 187 | filp->f_op = fops_get(dev->driver->fops); |
| 188 | if (filp->f_op == NULL) { |
| 189 | filp->f_op = old_fops; |
| 190 | goto out; |
| 191 | } |
| 192 | if (filp->f_op->open && (err = filp->f_op->open(inode, filp))) { |
| 193 | fops_put(filp->f_op); |
| 194 | filp->f_op = fops_get(old_fops); |
| 195 | } |
| 196 | fops_put(old_fops); |
| 197 | |
| 198 | out: |
| 199 | mutex_unlock(&drm_global_mutex); |
| 200 | return err; |
| 201 | } |
| 202 | |
| 203 | /** |
| 204 | * Check whether DRI will run on this CPU. |
| 205 | * |
| 206 | * \return non-zero if the DRI will run on this CPU, or zero otherwise. |
| 207 | */ |
| 208 | static int drm_cpu_valid(void) |
| 209 | { |
| 210 | #if defined(__i386__) |
| 211 | if (boot_cpu_data.x86 == 3) |
| 212 | return 0; /* No cmpxchg on a 386 */ |
| 213 | #endif |
| 214 | #if defined(__sparc__) && !defined(__sparc_v9__) |
| 215 | return 0; /* No cmpxchg before v9 sparc. */ |
| 216 | #endif |
| 217 | return 1; |
| 218 | } |
| 219 | |
| 220 | /** |
| 221 | * Called whenever a process opens /dev/drm. |
| 222 | * |
| 223 | * \param inode device inode. |
| 224 | * \param filp file pointer. |
| 225 | * \param dev device. |
| 226 | * \return zero on success or a negative number on failure. |
| 227 | * |
| 228 | * Creates and initializes a drm_file structure for the file private data in \p |
| 229 | * filp and add it into the double linked list in \p dev. |
| 230 | */ |
| 231 | static int drm_open_helper(struct inode *inode, struct file *filp, |
| 232 | struct drm_device * dev) |
| 233 | { |
| 234 | int minor_id = iminor(inode); |
| 235 | struct drm_file *priv; |
| 236 | int ret; |
| 237 | |
| 238 | if (filp->f_flags & O_EXCL) |
| 239 | return -EBUSY; /* No exclusive opens */ |
| 240 | if (!drm_cpu_valid()) |
| 241 | return -EINVAL; |
| 242 | if (dev->switch_power_state != DRM_SWITCH_POWER_ON) |
| 243 | return -EINVAL; |
| 244 | |
| 245 | DRM_DEBUG("pid = %d, minor = %d\n", task_pid_nr(current), minor_id); |
| 246 | |
| 247 | priv = kzalloc(sizeof(*priv), GFP_KERNEL); |
| 248 | if (!priv) |
| 249 | return -ENOMEM; |
| 250 | |
| 251 | filp->private_data = priv; |
| 252 | priv->filp = filp; |
| 253 | priv->uid = current_euid(); |
| 254 | priv->pid = task_pid_nr(current); |
| 255 | priv->minor = idr_find(&drm_minors_idr, minor_id); |
| 256 | priv->ioctl_count = 0; |
| 257 | /* for compatibility root is always authenticated */ |
| 258 | priv->authenticated = capable(CAP_SYS_ADMIN); |
| 259 | priv->lock_count = 0; |
| 260 | |
| 261 | INIT_LIST_HEAD(&priv->lhead); |
| 262 | INIT_LIST_HEAD(&priv->fbs); |
| 263 | INIT_LIST_HEAD(&priv->event_list); |
| 264 | init_waitqueue_head(&priv->event_wait); |
| 265 | priv->event_space = 4096; /* set aside 4k for event buffer */ |
| 266 | |
| 267 | if (dev->driver->driver_features & DRIVER_GEM) |
| 268 | drm_gem_open(dev, priv); |
| 269 | |
| 270 | if (drm_core_check_feature(dev, DRIVER_PRIME)) |
| 271 | drm_prime_init_file_private(&priv->prime); |
| 272 | |
| 273 | if (dev->driver->open) { |
| 274 | ret = dev->driver->open(dev, priv); |
| 275 | if (ret < 0) |
| 276 | goto out_free; |
| 277 | } |
| 278 | |
| 279 | |
| 280 | /* if there is no current master make this fd it */ |
| 281 | mutex_lock(&dev->struct_mutex); |
| 282 | if (!priv->minor->master) { |
| 283 | /* create a new master */ |
| 284 | priv->minor->master = drm_master_create(priv->minor); |
| 285 | if (!priv->minor->master) { |
| 286 | mutex_unlock(&dev->struct_mutex); |
| 287 | ret = -ENOMEM; |
| 288 | goto out_free; |
| 289 | } |
| 290 | |
| 291 | priv->is_master = 1; |
| 292 | /* take another reference for the copy in the local file priv */ |
| 293 | priv->master = drm_master_get(priv->minor->master); |
| 294 | |
| 295 | priv->authenticated = 1; |
| 296 | |
| 297 | mutex_unlock(&dev->struct_mutex); |
| 298 | if (dev->driver->master_create) { |
| 299 | ret = dev->driver->master_create(dev, priv->master); |
| 300 | if (ret) { |
| 301 | mutex_lock(&dev->struct_mutex); |
| 302 | /* drop both references if this fails */ |
| 303 | drm_master_put(&priv->minor->master); |
| 304 | drm_master_put(&priv->master); |
| 305 | mutex_unlock(&dev->struct_mutex); |
| 306 | goto out_free; |
| 307 | } |
| 308 | } |
| 309 | mutex_lock(&dev->struct_mutex); |
| 310 | if (dev->driver->master_set) { |
| 311 | ret = dev->driver->master_set(dev, priv, true); |
| 312 | if (ret) { |
| 313 | /* drop both references if this fails */ |
| 314 | drm_master_put(&priv->minor->master); |
| 315 | drm_master_put(&priv->master); |
| 316 | mutex_unlock(&dev->struct_mutex); |
| 317 | goto out_free; |
| 318 | } |
| 319 | } |
| 320 | mutex_unlock(&dev->struct_mutex); |
| 321 | } else { |
| 322 | /* get a reference to the master */ |
| 323 | priv->master = drm_master_get(priv->minor->master); |
| 324 | mutex_unlock(&dev->struct_mutex); |
| 325 | } |
| 326 | |
| 327 | mutex_lock(&dev->struct_mutex); |
| 328 | list_add(&priv->lhead, &dev->filelist); |
| 329 | mutex_unlock(&dev->struct_mutex); |
| 330 | |
| 331 | #ifdef __alpha__ |
| 332 | /* |
| 333 | * Default the hose |
| 334 | */ |
| 335 | if (!dev->hose) { |
| 336 | struct pci_dev *pci_dev; |
| 337 | pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); |
| 338 | if (pci_dev) { |
| 339 | dev->hose = pci_dev->sysdata; |
| 340 | pci_dev_put(pci_dev); |
| 341 | } |
| 342 | if (!dev->hose) { |
| 343 | struct pci_bus *b = pci_bus_b(pci_root_buses.next); |
| 344 | if (b) |
| 345 | dev->hose = b->sysdata; |
| 346 | } |
| 347 | } |
| 348 | #endif |
| 349 | |
| 350 | return 0; |
| 351 | out_free: |
| 352 | kfree(priv); |
| 353 | filp->private_data = NULL; |
| 354 | return ret; |
| 355 | } |
| 356 | |
| 357 | /** No-op. */ |
| 358 | int drm_fasync(int fd, struct file *filp, int on) |
| 359 | { |
| 360 | struct drm_file *priv = filp->private_data; |
| 361 | struct drm_device *dev = priv->minor->dev; |
| 362 | |
| 363 | DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, |
| 364 | (long)old_encode_dev(priv->minor->device)); |
| 365 | return fasync_helper(fd, filp, on, &dev->buf_async); |
| 366 | } |
| 367 | EXPORT_SYMBOL(drm_fasync); |
| 368 | |
| 369 | static void drm_master_release(struct drm_device *dev, struct file *filp) |
| 370 | { |
| 371 | struct drm_file *file_priv = filp->private_data; |
| 372 | |
| 373 | if (drm_i_have_hw_lock(dev, file_priv)) { |
| 374 | DRM_DEBUG("File %p released, freeing lock for context %d\n", |
| 375 | filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); |
| 376 | drm_lock_free(&file_priv->master->lock, |
| 377 | _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); |
| 378 | } |
| 379 | } |
| 380 | |
| 381 | static void drm_events_release(struct drm_file *file_priv) |
| 382 | { |
| 383 | struct drm_device *dev = file_priv->minor->dev; |
| 384 | struct drm_pending_event *e, *et; |
| 385 | struct drm_pending_vblank_event *v, *vt; |
| 386 | unsigned long flags; |
| 387 | |
| 388 | spin_lock_irqsave(&dev->event_lock, flags); |
| 389 | |
| 390 | /* Remove pending flips */ |
| 391 | list_for_each_entry_safe(v, vt, &dev->vblank_event_list, base.link) |
| 392 | if (v->base.file_priv == file_priv) { |
| 393 | list_del(&v->base.link); |
| 394 | drm_vblank_put(dev, v->pipe); |
| 395 | v->base.destroy(&v->base); |
| 396 | } |
| 397 | |
| 398 | /* Remove unconsumed events */ |
| 399 | list_for_each_entry_safe(e, et, &file_priv->event_list, link) |
| 400 | e->destroy(e); |
| 401 | |
| 402 | spin_unlock_irqrestore(&dev->event_lock, flags); |
| 403 | } |
| 404 | |
| 405 | /** |
| 406 | * Release file. |
| 407 | * |
| 408 | * \param inode device inode |
| 409 | * \param file_priv DRM file private. |
| 410 | * \return zero on success or a negative number on failure. |
| 411 | * |
| 412 | * If the hardware lock is held then free it, and take it again for the kernel |
| 413 | * context since it's necessary to reclaim buffers. Unlink the file private |
| 414 | * data from its list and free it. Decreases the open count and if it reaches |
| 415 | * zero calls drm_lastclose(). |
| 416 | */ |
| 417 | int drm_release(struct inode *inode, struct file *filp) |
| 418 | { |
| 419 | struct drm_file *file_priv = filp->private_data; |
| 420 | struct drm_device *dev = file_priv->minor->dev; |
| 421 | int retcode = 0; |
| 422 | |
| 423 | mutex_lock(&drm_global_mutex); |
| 424 | |
| 425 | DRM_DEBUG("open_count = %d\n", dev->open_count); |
| 426 | |
| 427 | if (dev->driver->preclose) |
| 428 | dev->driver->preclose(dev, file_priv); |
| 429 | |
| 430 | /* ======================================================== |
| 431 | * Begin inline drm_release |
| 432 | */ |
| 433 | |
| 434 | DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", |
| 435 | task_pid_nr(current), |
| 436 | (long)old_encode_dev(file_priv->minor->device), |
| 437 | dev->open_count); |
| 438 | |
| 439 | /* Release any auth tokens that might point to this file_priv, |
| 440 | (do that under the drm_global_mutex) */ |
| 441 | if (file_priv->magic) |
| 442 | (void) drm_remove_magic(file_priv->master, file_priv->magic); |
| 443 | |
| 444 | /* if the master has gone away we can't do anything with the lock */ |
| 445 | if (file_priv->minor->master) |
| 446 | drm_master_release(dev, filp); |
| 447 | |
| 448 | if (drm_core_check_feature(dev, DRIVER_HAVE_DMA)) |
| 449 | drm_core_reclaim_buffers(dev, file_priv); |
| 450 | |
| 451 | drm_events_release(file_priv); |
| 452 | |
| 453 | if (dev->driver->driver_features & DRIVER_MODESET) |
| 454 | drm_fb_release(file_priv); |
| 455 | |
| 456 | if (dev->driver->driver_features & DRIVER_GEM) |
| 457 | drm_gem_release(dev, file_priv); |
| 458 | |
| 459 | mutex_lock(&dev->ctxlist_mutex); |
| 460 | if (!list_empty(&dev->ctxlist)) { |
| 461 | struct drm_ctx_list *pos, *n; |
| 462 | |
| 463 | list_for_each_entry_safe(pos, n, &dev->ctxlist, head) { |
| 464 | if (pos->tag == file_priv && |
| 465 | pos->handle != DRM_KERNEL_CONTEXT) { |
| 466 | if (dev->driver->context_dtor) |
| 467 | dev->driver->context_dtor(dev, |
| 468 | pos->handle); |
| 469 | |
| 470 | drm_ctxbitmap_free(dev, pos->handle); |
| 471 | |
| 472 | list_del(&pos->head); |
| 473 | kfree(pos); |
| 474 | --dev->ctx_count; |
| 475 | } |
| 476 | } |
| 477 | } |
| 478 | mutex_unlock(&dev->ctxlist_mutex); |
| 479 | |
| 480 | mutex_lock(&dev->struct_mutex); |
| 481 | |
| 482 | if (file_priv->is_master) { |
| 483 | struct drm_master *master = file_priv->master; |
| 484 | struct drm_file *temp; |
| 485 | list_for_each_entry(temp, &dev->filelist, lhead) { |
| 486 | if ((temp->master == file_priv->master) && |
| 487 | (temp != file_priv)) |
| 488 | temp->authenticated = 0; |
| 489 | } |
| 490 | |
| 491 | /** |
| 492 | * Since the master is disappearing, so is the |
| 493 | * possibility to lock. |
| 494 | */ |
| 495 | |
| 496 | if (master->lock.hw_lock) { |
| 497 | if (dev->sigdata.lock == master->lock.hw_lock) |
| 498 | dev->sigdata.lock = NULL; |
| 499 | master->lock.hw_lock = NULL; |
| 500 | master->lock.file_priv = NULL; |
| 501 | wake_up_interruptible_all(&master->lock.lock_queue); |
| 502 | } |
| 503 | |
| 504 | if (file_priv->minor->master == file_priv->master) { |
| 505 | /* drop the reference held my the minor */ |
| 506 | if (dev->driver->master_drop) |
| 507 | dev->driver->master_drop(dev, file_priv, true); |
| 508 | drm_master_put(&file_priv->minor->master); |
| 509 | } |
| 510 | } |
| 511 | |
| 512 | BUG_ON(dev->dev_mapping == NULL); |
| 513 | iput(container_of(dev->dev_mapping, struct inode, i_data)); |
| 514 | |
| 515 | /* drop the reference held my the file priv */ |
| 516 | drm_master_put(&file_priv->master); |
| 517 | file_priv->is_master = 0; |
| 518 | list_del(&file_priv->lhead); |
| 519 | mutex_unlock(&dev->struct_mutex); |
| 520 | |
| 521 | if (dev->driver->postclose) |
| 522 | dev->driver->postclose(dev, file_priv); |
| 523 | |
| 524 | if (drm_core_check_feature(dev, DRIVER_PRIME)) |
| 525 | drm_prime_destroy_file_private(&file_priv->prime); |
| 526 | |
| 527 | kfree(file_priv); |
| 528 | |
| 529 | /* ======================================================== |
| 530 | * End inline drm_release |
| 531 | */ |
| 532 | |
| 533 | atomic_inc(&dev->counts[_DRM_STAT_CLOSES]); |
| 534 | if (!--dev->open_count) { |
| 535 | if (atomic_read(&dev->ioctl_count)) { |
| 536 | DRM_ERROR("Device busy: %d\n", |
| 537 | atomic_read(&dev->ioctl_count)); |
| 538 | retcode = -EBUSY; |
| 539 | } else |
| 540 | retcode = drm_lastclose(dev); |
| 541 | if (drm_device_is_unplugged(dev)) |
| 542 | drm_put_dev(dev); |
| 543 | } |
| 544 | mutex_unlock(&drm_global_mutex); |
| 545 | |
| 546 | return retcode; |
| 547 | } |
| 548 | EXPORT_SYMBOL(drm_release); |
| 549 | |
| 550 | static bool |
| 551 | drm_dequeue_event(struct drm_file *file_priv, |
| 552 | size_t total, size_t max, struct drm_pending_event **out) |
| 553 | { |
| 554 | struct drm_device *dev = file_priv->minor->dev; |
| 555 | struct drm_pending_event *e; |
| 556 | unsigned long flags; |
| 557 | bool ret = false; |
| 558 | |
| 559 | spin_lock_irqsave(&dev->event_lock, flags); |
| 560 | |
| 561 | *out = NULL; |
| 562 | if (list_empty(&file_priv->event_list)) |
| 563 | goto out; |
| 564 | e = list_first_entry(&file_priv->event_list, |
| 565 | struct drm_pending_event, link); |
| 566 | if (e->event->length + total > max) |
| 567 | goto out; |
| 568 | |
| 569 | file_priv->event_space += e->event->length; |
| 570 | list_del(&e->link); |
| 571 | *out = e; |
| 572 | ret = true; |
| 573 | |
| 574 | out: |
| 575 | spin_unlock_irqrestore(&dev->event_lock, flags); |
| 576 | return ret; |
| 577 | } |
| 578 | |
| 579 | ssize_t drm_read(struct file *filp, char __user *buffer, |
| 580 | size_t count, loff_t *offset) |
| 581 | { |
| 582 | struct drm_file *file_priv = filp->private_data; |
| 583 | struct drm_pending_event *e; |
| 584 | size_t total; |
| 585 | ssize_t ret; |
| 586 | |
| 587 | ret = wait_event_interruptible(file_priv->event_wait, |
| 588 | !list_empty(&file_priv->event_list)); |
| 589 | if (ret < 0) |
| 590 | return ret; |
| 591 | |
| 592 | total = 0; |
| 593 | while (drm_dequeue_event(file_priv, total, count, &e)) { |
| 594 | if (copy_to_user(buffer + total, |
| 595 | e->event, e->event->length)) { |
| 596 | total = -EFAULT; |
| 597 | break; |
| 598 | } |
| 599 | |
| 600 | total += e->event->length; |
| 601 | e->destroy(e); |
| 602 | } |
| 603 | |
| 604 | return total; |
| 605 | } |
| 606 | EXPORT_SYMBOL(drm_read); |
| 607 | |
| 608 | unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) |
| 609 | { |
| 610 | struct drm_file *file_priv = filp->private_data; |
| 611 | unsigned int mask = 0; |
| 612 | |
| 613 | poll_wait(filp, &file_priv->event_wait, wait); |
| 614 | |
| 615 | if (!list_empty(&file_priv->event_list)) |
| 616 | mask |= POLLIN | POLLRDNORM; |
| 617 | |
| 618 | return mask; |
| 619 | } |
| 620 | EXPORT_SYMBOL(drm_poll); |