drm_fops.c revision f41ced8f108cc80f16509b907cd7ac93944459bc
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 = drm_alloc(sizeof(*priv), DRM_MEM_FILES); 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); 260 261 if (dev->driver->driver_features & DRIVER_GEM) 262 drm_gem_open(dev, priv); 263 264 if (dev->driver->open) { 265 ret = dev->driver->open(dev, priv); 266 if (ret < 0) 267 goto out_free; 268 } 269 270 271 /* if there is no current master make this fd it */ 272 mutex_lock(&dev->struct_mutex); 273 if (!priv->minor->master) { 274 /* create a new master */ 275 priv->minor->master = drm_master_create(priv->minor); 276 if (!priv->minor->master) { 277 ret = -ENOMEM; 278 goto out_free; 279 } 280 281 priv->is_master = 1; 282 /* take another reference for the copy in the local file priv */ 283 priv->master = drm_master_get(priv->minor->master); 284 285 priv->authenticated = 1; 286 287 mutex_unlock(&dev->struct_mutex); 288 if (dev->driver->master_create) { 289 ret = dev->driver->master_create(dev, priv->master); 290 if (ret) { 291 mutex_lock(&dev->struct_mutex); 292 /* drop both references if this fails */ 293 drm_master_put(&priv->minor->master); 294 drm_master_put(&priv->master); 295 mutex_unlock(&dev->struct_mutex); 296 goto out_free; 297 } 298 } 299 } else { 300 /* get a reference to the master */ 301 priv->master = drm_master_get(priv->minor->master); 302 mutex_unlock(&dev->struct_mutex); 303 } 304 305 mutex_lock(&dev->struct_mutex); 306 list_add(&priv->lhead, &dev->filelist); 307 mutex_unlock(&dev->struct_mutex); 308 309#ifdef __alpha__ 310 /* 311 * Default the hose 312 */ 313 if (!dev->hose) { 314 struct pci_dev *pci_dev; 315 pci_dev = pci_get_class(PCI_CLASS_DISPLAY_VGA << 8, NULL); 316 if (pci_dev) { 317 dev->hose = pci_dev->sysdata; 318 pci_dev_put(pci_dev); 319 } 320 if (!dev->hose) { 321 struct pci_bus *b = pci_bus_b(pci_root_buses.next); 322 if (b) 323 dev->hose = b->sysdata; 324 } 325 } 326#endif 327 328 return 0; 329 out_free: 330 drm_free(priv, sizeof(*priv), DRM_MEM_FILES); 331 filp->private_data = NULL; 332 return ret; 333} 334 335/** No-op. */ 336int drm_fasync(int fd, struct file *filp, int on) 337{ 338 struct drm_file *priv = filp->private_data; 339 struct drm_device *dev = priv->minor->dev; 340 int retcode; 341 342 DRM_DEBUG("fd = %d, device = 0x%lx\n", fd, 343 (long)old_encode_dev(priv->minor->device)); 344 retcode = fasync_helper(fd, filp, on, &dev->buf_async); 345 if (retcode < 0) 346 return retcode; 347 return 0; 348} 349EXPORT_SYMBOL(drm_fasync); 350 351/* 352 * Reclaim locked buffers; note that this may be a bad idea if the current 353 * context doesn't have the hw lock... 354 */ 355static void drm_reclaim_locked_buffers(struct drm_device *dev, struct file *f) 356{ 357 struct drm_file *file_priv = f->private_data; 358 359 if (drm_i_have_hw_lock(dev, file_priv)) { 360 dev->driver->reclaim_buffers_locked(dev, file_priv); 361 } else { 362 unsigned long _end = jiffies + 3 * DRM_HZ; 363 int locked = 0; 364 365 drm_idlelock_take(&file_priv->master->lock); 366 367 /* 368 * Wait for a while. 369 */ 370 do { 371 spin_lock_bh(&file_priv->master->lock.spinlock); 372 locked = file_priv->master->lock.idle_has_lock; 373 spin_unlock_bh(&file_priv->master->lock.spinlock); 374 if (locked) 375 break; 376 schedule(); 377 } while (!time_after_eq(jiffies, _end)); 378 379 if (!locked) { 380 DRM_ERROR("reclaim_buffers_locked() deadlock. Please rework this\n" 381 "\tdriver to use reclaim_buffers_idlelocked() instead.\n" 382 "\tI will go on reclaiming the buffers anyway.\n"); 383 } 384 385 dev->driver->reclaim_buffers_locked(dev, file_priv); 386 drm_idlelock_release(&file_priv->master->lock); 387 } 388} 389 390static void drm_master_release(struct drm_device *dev, struct file *filp) 391{ 392 struct drm_file *file_priv = filp->private_data; 393 394 if (dev->driver->reclaim_buffers_locked && 395 file_priv->master->lock.hw_lock) 396 drm_reclaim_locked_buffers(dev, filp); 397 398 if (dev->driver->reclaim_buffers_idlelocked && 399 file_priv->master->lock.hw_lock) { 400 drm_idlelock_take(&file_priv->master->lock); 401 dev->driver->reclaim_buffers_idlelocked(dev, file_priv); 402 drm_idlelock_release(&file_priv->master->lock); 403 } 404 405 406 if (drm_i_have_hw_lock(dev, file_priv)) { 407 DRM_DEBUG("File %p released, freeing lock for context %d\n", 408 filp, _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 409 drm_lock_free(&file_priv->master->lock, 410 _DRM_LOCKING_CONTEXT(file_priv->master->lock.hw_lock->lock)); 411 } 412 413 if (drm_core_check_feature(dev, DRIVER_HAVE_DMA) && 414 !dev->driver->reclaim_buffers_locked) { 415 dev->driver->reclaim_buffers(dev, file_priv); 416 } 417} 418 419/** 420 * Release file. 421 * 422 * \param inode device inode 423 * \param file_priv DRM file private. 424 * \return zero on success or a negative number on failure. 425 * 426 * If the hardware lock is held then free it, and take it again for the kernel 427 * context since it's necessary to reclaim buffers. Unlink the file private 428 * data from its list and free it. Decreases the open count and if it reaches 429 * zero calls drm_lastclose(). 430 */ 431int drm_release(struct inode *inode, struct file *filp) 432{ 433 struct drm_file *file_priv = filp->private_data; 434 struct drm_device *dev = file_priv->minor->dev; 435 int retcode = 0; 436 437 lock_kernel(); 438 439 DRM_DEBUG("open_count = %d\n", dev->open_count); 440 441 if (dev->driver->preclose) 442 dev->driver->preclose(dev, file_priv); 443 444 /* ======================================================== 445 * Begin inline drm_release 446 */ 447 448 DRM_DEBUG("pid = %d, device = 0x%lx, open_count = %d\n", 449 task_pid_nr(current), 450 (long)old_encode_dev(file_priv->minor->device), 451 dev->open_count); 452 453 /* if the master has gone away we can't do anything with the lock */ 454 if (file_priv->minor->master) 455 drm_master_release(dev, filp); 456 457 if (dev->driver->driver_features & DRIVER_GEM) 458 drm_gem_release(dev, file_priv); 459 460 mutex_lock(&dev->ctxlist_mutex); 461 if (!list_empty(&dev->ctxlist)) { 462 struct drm_ctx_list *pos, *n; 463 464 list_for_each_entry_safe(pos, n, &dev->ctxlist, head) { 465 if (pos->tag == file_priv && 466 pos->handle != DRM_KERNEL_CONTEXT) { 467 if (dev->driver->context_dtor) 468 dev->driver->context_dtor(dev, 469 pos->handle); 470 471 drm_ctxbitmap_free(dev, pos->handle); 472 473 list_del(&pos->head); 474 drm_free(pos, sizeof(*pos), DRM_MEM_CTXLIST); 475 --dev->ctx_count; 476 } 477 } 478 } 479 mutex_unlock(&dev->ctxlist_mutex); 480 481 mutex_lock(&dev->struct_mutex); 482 483 if (file_priv->is_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 if (file_priv->minor->master == file_priv->master) { 492 /* drop the reference held my the minor */ 493 drm_master_put(&file_priv->minor->master); 494 } 495 } 496 497 /* drop the reference held my the file priv */ 498 drm_master_put(&file_priv->master); 499 file_priv->is_master = 0; 500 list_del(&file_priv->lhead); 501 mutex_unlock(&dev->struct_mutex); 502 503 if (dev->driver->postclose) 504 dev->driver->postclose(dev, file_priv); 505 drm_free(file_priv, sizeof(*file_priv), DRM_MEM_FILES); 506 507 /* ======================================================== 508 * End inline drm_release 509 */ 510 511 atomic_inc(&dev->counts[_DRM_STAT_CLOSES]); 512 spin_lock(&dev->count_lock); 513 if (!--dev->open_count) { 514 if (atomic_read(&dev->ioctl_count)) { 515 DRM_ERROR("Device busy: %d\n", 516 atomic_read(&dev->ioctl_count)); 517 spin_unlock(&dev->count_lock); 518 unlock_kernel(); 519 return -EBUSY; 520 } 521 spin_unlock(&dev->count_lock); 522 unlock_kernel(); 523 return drm_lastclose(dev); 524 } 525 spin_unlock(&dev->count_lock); 526 527 unlock_kernel(); 528 529 return retcode; 530} 531EXPORT_SYMBOL(drm_release); 532 533/** No-op. */ 534unsigned int drm_poll(struct file *filp, struct poll_table_struct *wait) 535{ 536 return 0; 537} 538EXPORT_SYMBOL(drm_poll); 539