sys/dev/drm/drm_syncobj.c

   1 /*
   2  * Copyright 2017 Red Hat
   3  * Parts ported from amdgpu (fence wait code).
   4  * Copyright 2016 Advanced Micro Devices, Inc.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the next
  14  * paragraph) shall be included in all copies or substantial portions of the
  15  * Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  23  * IN THE SOFTWARE.
  24  *
  25  * Authors:
  26  *
  27  */
  28
  29 /**
  30  * DOC: Overview
  31  *
  32  * DRM synchronisation objects (syncobj) are a persistent objects,
  33  * that contain an optional fence. The fence can be updated with a new
  34  * fence, or be NULL.
  35  *
  36  * syncobj's can be waited upon, where it will wait for the underlying
  37  * fence.
  38  *
  39  * syncobj's can be export to fd's and back, these fd's are opaque and
  40  * have no other use case, except passing the syncobj between processes.
  41  *
  42  * Their primary use-case is to implement Vulkan fences and semaphores.
  43  *
  44  * syncobj have a kref reference count, but also have an optional file.
  45  * The file is only created once the syncobj is exported.
  46  * The file takes a reference on the kref.
  47  */
  48
  49 #include <drm/drmP.h>
  50 #include <linux/file.h>
  51 #include <linux/fs.h>
  52 #include <linux/anon_inodes.h>
  53 #include <linux/sync_file.h>
  54 #include <linux/sched/signal.h>
  55
  56 #include "drm_internal.h"
  57 #include <drm/drm_syncobj.h>
  58
  59 /**
  60  * drm_syncobj_find - lookup and reference a sync object.
  61  * @file_private: drm file private pointer
  62  * @handle: sync object handle to lookup.
  63  *
  64  * Returns a reference to the syncobj pointed to by handle or NULL.
  65  */
  66 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
  67                                      u32 handle)
  68 {
  69         struct drm_syncobj *syncobj;
  70
  71         lockmgr(&file_private->syncobj_table_lock, LK_EXCLUSIVE);
  72
  73         /* Check if we currently have a reference on the object */
  74         syncobj = idr_find(&file_private->syncobj_idr, handle);
  75         if (syncobj)
  76                 drm_syncobj_get(syncobj);
  77
  78         lockmgr(&file_private->syncobj_table_lock, LK_RELEASE);
  79
  80         return syncobj;
  81 }
  82 EXPORT_SYMBOL(drm_syncobj_find);
  83
  84 static void drm_syncobj_add_callback_locked(struct drm_syncobj *syncobj,
  85                                             struct drm_syncobj_cb *cb,
  86                                             drm_syncobj_func_t func)
  87 {
  88         cb->func = func;
  89         list_add_tail(&cb->node, &syncobj->cb_list);
  90 }
  91
  92 #if 0
  93 static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
  94                                                  struct dma_fence **fence,
  95                                                  struct drm_syncobj_cb *cb,
  96                                                  drm_syncobj_func_t func)
  97 {
  98         int ret;
  99
 100         *fence = drm_syncobj_fence_get(syncobj);
 101         if (*fence)
 102                 return 1;
 103
 104         lockmgr(&syncobj->lock, LK_EXCLUSIVE);
 105         /* We've already tried once to get a fence and failed.  Now that we
 106          * have the lock, try one more time just to be sure we don't add a
 107          * callback when a fence has already been set.
 108          */
 109         if (syncobj->fence) {
 110                 *fence = dma_fence_get(syncobj->fence);
 111                 ret = 1;
 112         } else {
 113                 *fence = NULL;
 114                 drm_syncobj_add_callback_locked(syncobj, cb, func);
 115                 ret = 0;
 116         }
 117         lockmgr(&syncobj->lock, LK_RELEASE);
 118
 119         return ret;
 120 }
 121 #endif
 122
 123 /**
 124  * drm_syncobj_add_callback - adds a callback to syncobj::cb_list
 125  * @syncobj: Sync object to which to add the callback
 126  * @cb: Callback to add
 127  * @func: Func to use when initializing the drm_syncobj_cb struct
 128  *
 129  * This adds a callback to be called next time the fence is replaced
 130  */
 131 void drm_syncobj_add_callback(struct drm_syncobj *syncobj,
 132                               struct drm_syncobj_cb *cb,
 133                               drm_syncobj_func_t func)
 134 {
 135         lockmgr(&syncobj->lock, LK_EXCLUSIVE);
 136         drm_syncobj_add_callback_locked(syncobj, cb, func);
 137         lockmgr(&syncobj->lock, LK_RELEASE);
 138 }
 139 EXPORT_SYMBOL(drm_syncobj_add_callback);
 140
 141 /**
 142  * drm_syncobj_add_callback - removes a callback to syncobj::cb_list
 143  * @syncobj: Sync object from which to remove the callback
 144  * @cb: Callback to remove
 145  */
 146 void drm_syncobj_remove_callback(struct drm_syncobj *syncobj,
 147                                  struct drm_syncobj_cb *cb)
 148 {
 149         lockmgr(&syncobj->lock, LK_EXCLUSIVE);
 150         list_del_init(&cb->node);
 151         lockmgr(&syncobj->lock, LK_RELEASE);
 152 }
 153 EXPORT_SYMBOL(drm_syncobj_remove_callback);
 154
 155 /**
 156  * drm_syncobj_replace_fence - replace fence in a sync object.
 157  * @syncobj: Sync object to replace fence in
 158  * @fence: fence to install in sync file.
 159  *
 160  * This replaces the fence on a sync object.
 161  */
 162 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
 163                                struct dma_fence *fence)
 164 {
 165         struct dma_fence *old_fence;
 166         struct drm_syncobj_cb *cur, *tmp;
 167
 168         if (fence)
 169                 dma_fence_get(fence);
 170
 171         lockmgr(&syncobj->lock, LK_EXCLUSIVE);
 172
 173         old_fence = syncobj->fence;
 174         syncobj->fence = fence;
 175
 176         if (fence != old_fence) {
 177                 list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node) {
 178                         list_del_init(&cur->node);
 179                         cur->func(syncobj, cur);
 180                 }
 181         }
 182
 183         lockmgr(&syncobj->lock, LK_RELEASE);
 184
 185         dma_fence_put(old_fence);
 186 }
 187 EXPORT_SYMBOL(drm_syncobj_replace_fence);
 188
 189 struct drm_syncobj_null_fence {
 190         struct dma_fence base;
 191         spinlock_t lock;
 192 };
 193
 194 static const char *drm_syncobj_null_fence_get_name(struct dma_fence *fence)
 195 {
 196         return "syncobjnull";
 197 }
 198
 199 static bool drm_syncobj_null_fence_enable_signaling(struct dma_fence *fence)
 200 {
 201     dma_fence_enable_sw_signaling(fence);
 202     return !dma_fence_is_signaled(fence);
 203 }
 204
 205 static const struct dma_fence_ops drm_syncobj_null_fence_ops = {
 206         .get_driver_name = drm_syncobj_null_fence_get_name,
 207         .get_timeline_name = drm_syncobj_null_fence_get_name,
 208         .enable_signaling = drm_syncobj_null_fence_enable_signaling,
 209         .wait = dma_fence_default_wait,
 210         .release = NULL,
 211 };
 212
 213 static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
 214 {
 215         struct drm_syncobj_null_fence *fence;
 216         fence = kzalloc(sizeof(*fence), GFP_KERNEL);
 217         if (fence == NULL)
 218                 return -ENOMEM;
 219
 220         lockinit(&fence->lock, "dsofl", 0, 0);
 221         dma_fence_init(&fence->base, &drm_syncobj_null_fence_ops,
 222                        &fence->lock, 0, 0);
 223         dma_fence_signal(&fence->base);
 224
 225         drm_syncobj_replace_fence(syncobj, &fence->base);
 226
 227         dma_fence_put(&fence->base);
 228
 229         return 0;
 230 }
 231
 232 int drm_syncobj_find_fence(struct drm_file *file_private,
 233                            u32 handle,
 234                            struct dma_fence **fence)
 235 {
 236         struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
 237         int ret = 0;
 238
 239         if (!syncobj)
 240                 return -ENOENT;
 241
 242         *fence = drm_syncobj_fence_get(syncobj);
 243         if (!*fence) {
 244                 ret = -EINVAL;
 245         }
 246         drm_syncobj_put(syncobj);
 247         return ret;
 248 }
 249 EXPORT_SYMBOL(drm_syncobj_find_fence);
 250
 251 /**
 252  * drm_syncobj_free - free a sync object.
 253  * @kref: kref to free.
 254  *
 255  * Only to be called from kref_put in drm_syncobj_put.
 256  */
 257 void drm_syncobj_free(struct kref *kref)
 258 {
 259         struct drm_syncobj *syncobj = container_of(kref,
 260                                                    struct drm_syncobj,
 261                                                    refcount);
 262         drm_syncobj_replace_fence(syncobj, NULL);
 263         kfree(syncobj);
 264 }
 265 EXPORT_SYMBOL(drm_syncobj_free);
 266
 267 /**
 268  * drm_syncobj_create - create a new syncobj
 269  * @out_syncobj: returned syncobj
 270  * @flags: DRM_SYNCOBJ_* flags
 271  * @fence: if non-NULL, the syncobj will represent this fence
 272  */
 273 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 274                        struct dma_fence *fence)
 275 {
 276         int ret;
 277         struct drm_syncobj *syncobj;
 278
 279         syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);
 280         if (!syncobj)
 281                 return -ENOMEM;
 282
 283         kref_init(&syncobj->refcount);
 284         INIT_LIST_HEAD(&syncobj->cb_list);
 285         lockinit(&syncobj->lock, "dsol", 0, 0);
 286
 287         if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
 288                 ret = drm_syncobj_assign_null_handle(syncobj);
 289                 if (ret < 0) {
 290                         drm_syncobj_put(syncobj);
 291                         return ret;
 292                 }
 293         }
 294
 295         if (fence)
 296                 drm_syncobj_replace_fence(syncobj, fence);
 297
 298         *out_syncobj = syncobj;
 299         return 0;
 300 }
 301 EXPORT_SYMBOL(drm_syncobj_create);
 302
 303 /**
 304  * drm_syncobj_get_handle - get a handle from a syncobj
 305  */
 306 int drm_syncobj_get_handle(struct drm_file *file_private,
 307                            struct drm_syncobj *syncobj, u32 *handle)
 308 {
 309         int ret;
 310
 311         /* take a reference to put in the idr */
 312         drm_syncobj_get(syncobj);
 313
 314         idr_preload(GFP_KERNEL);
 315         lockmgr(&file_private->syncobj_table_lock, LK_EXCLUSIVE);
 316         ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
 317         lockmgr(&file_private->syncobj_table_lock, LK_RELEASE);
 318
 319         idr_preload_end();
 320
 321         if (ret < 0) {
 322                 drm_syncobj_put(syncobj);
 323                 return ret;
 324         }
 325
 326         *handle = ret;
 327         return 0;
 328 }
 329 EXPORT_SYMBOL(drm_syncobj_get_handle);
 330
 331 static int drm_syncobj_create_as_handle(struct drm_file *file_private,
 332                                         u32 *handle, uint32_t flags)
 333 {
 334         int ret;
 335         struct drm_syncobj *syncobj;
 336
 337         ret = drm_syncobj_create(&syncobj, flags, NULL);
 338         if (ret)
 339                 return ret;
 340
 341         ret = drm_syncobj_get_handle(file_private, syncobj, handle);
 342         drm_syncobj_put(syncobj);
 343         return ret;
 344 }
 345
 346 static int drm_syncobj_destroy(struct drm_file *file_private,
 347                                u32 handle)
 348 {
 349         struct drm_syncobj *syncobj;
 350
 351         lockmgr(&file_private->syncobj_table_lock, LK_EXCLUSIVE);
 352         syncobj = idr_remove(&file_private->syncobj_idr, handle);
 353         lockmgr(&file_private->syncobj_table_lock, LK_RELEASE);
 354
 355         if (!syncobj)
 356                 return -EINVAL;
 357
 358         drm_syncobj_put(syncobj);
 359         return 0;
 360 }
 361
 362 #if 0
 363 static int drm_syncobj_file_release(struct inode *inode, struct file *file)
 364 {
 365         struct drm_syncobj *syncobj = file->private_data;
 366
 367         drm_syncobj_put(syncobj);
 368         return 0;
 369 }
 370
 371 static const struct file_operations drm_syncobj_file_fops = {
 372         .release = drm_syncobj_file_release,
 373 };
 374 #endif
 375
 376 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
 377 {
 378         struct file *file;
 379         int fd;
 380
 381         fd = get_unused_fd_flags(O_CLOEXEC);
 382         if (fd < 0)
 383                 return fd;
 384
 385 #if 0
 386         file = anon_inode_getfile("syncobj_file",
 387                                   &drm_syncobj_file_fops,
 388                                   syncobj, 0);
 389         if (IS_ERR(file)) {
 390                 put_unused_fd(fd);
 391                 return PTR_ERR(file);
 392         }
 393 #else
 394         return -EINVAL;
 395 #endif
 396
 397         drm_syncobj_get(syncobj);
 398         fd_install(fd, file);
 399
 400         *p_fd = fd;
 401         return 0;
 402 }
 403 EXPORT_SYMBOL(drm_syncobj_get_fd);
 404
 405 static int drm_syncobj_handle_to_fd(struct drm_file *file_private,
 406                                     u32 handle, int *p_fd)
 407 {
 408         struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
 409         int ret;
 410
 411         if (!syncobj)
 412                 return -EINVAL;
 413
 414         ret = drm_syncobj_get_fd(syncobj, p_fd);
 415         drm_syncobj_put(syncobj);
 416         return ret;
 417 }
 418
 419 #if 0
 420 static struct drm_syncobj *drm_syncobj_fdget(int fd)
 421 {
 422         struct file *file = fget(fd);
 423
 424         if (!file)
 425                 return NULL;
 426         if (file->f_op != &drm_syncobj_file_fops)
 427                 goto err;
 428
 429         return file->private_data;
 430 err:
 431         fput(file);
 432         return NULL;
 433 };
 434 #endif
 435
 436 static int drm_syncobj_fd_to_handle(struct drm_file *file_private,
 437                                     int fd, u32 *handle)
 438 {
 439 #if 0
 440         struct drm_syncobj *syncobj;
 441         struct file *file;
 442         int ret;
 443
 444         file = fget(fd);
 445         if (!file)
 446                 return -EINVAL;
 447
 448         if (file->f_op != &drm_syncobj_file_fops) {
 449                 fput(file);
 450                 return -EINVAL;
 451         }
 452
 453         /* take a reference to put in the idr */
 454         syncobj = file->private_data;
 455         drm_syncobj_get(syncobj);
 456
 457         idr_preload(GFP_KERNEL);
 458         spin_lock(&file_private->syncobj_table_lock);
 459         ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
 460         spin_unlock(&file_private->syncobj_table_lock);
 461         idr_preload_end();
 462
 463         if (ret > 0) {
 464                 *handle = ret;
 465                 ret = 0;
 466         } else
 467                 drm_syncobj_put(syncobj);
 468
 469         fput(file);
 470         return ret;
 471 #endif
 472         return -EINVAL;
 473 }
 474
 475 static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
 476                                               int fd, int handle)
 477 {
 478         struct dma_fence *fence = sync_file_get_fence(fd);
 479         struct drm_syncobj *syncobj;
 480
 481         if (!fence)
 482                 return -EINVAL;
 483
 484         syncobj = drm_syncobj_find(file_private, handle);
 485         if (!syncobj) {
 486                 dma_fence_put(fence);
 487                 return -ENOENT;
 488         }
 489
 490         drm_syncobj_replace_fence(syncobj, fence);
 491         dma_fence_put(fence);
 492         drm_syncobj_put(syncobj);
 493         return 0;
 494 }
 495
 496 static int drm_syncobj_export_sync_file(struct drm_file *file_private,
 497                                         int handle, int *p_fd)
 498 {
 499         int ret;
 500         struct dma_fence *fence;
 501         struct sync_file *sync_file;
 502         int fd = get_unused_fd_flags(O_CLOEXEC);
 503
 504         if (fd < 0)
 505                 return fd;
 506
 507         ret = drm_syncobj_find_fence(file_private, handle, &fence);
 508         if (ret)
 509                 goto err_put_fd;
 510
 511         sync_file = sync_file_create(fence);
 512
 513         dma_fence_put(fence);
 514
 515         if (!sync_file) {
 516                 ret = -EINVAL;
 517                 goto err_put_fd;
 518         }
 519
 520         fd_install(fd, sync_file->file);
 521
 522         *p_fd = fd;
 523         return 0;
 524 err_put_fd:
 525         put_unused_fd(fd);
 526         return ret;
 527 }
 528 /**
 529  * drm_syncobj_open - initalizes syncobj file-private structures at devnode open time
 530  * @file_private: drm file-private structure to set up
 531  *
 532  * Called at device open time, sets up the structure for handling refcounting
 533  * of sync objects.
 534  */
 535 void
 536 drm_syncobj_open(struct drm_file *file_private)
 537 {
 538         idr_init(&file_private->syncobj_idr);
 539         lockinit(&file_private->syncobj_table_lock, "dsotl", 0, 0);
 540 }
 541
 542 static int
 543 drm_syncobj_release_handle(int id, void *ptr, void *data)
 544 {
 545         struct drm_syncobj *syncobj = ptr;
 546
 547         drm_syncobj_put(syncobj);
 548         return 0;
 549 }
 550
 551 /**
 552  * drm_syncobj_release - release file-private sync object resources
 553  * @file_private: drm file-private structure to clean up
 554  *
 555  * Called at close time when the filp is going away.
 556  *
 557  * Releases any remaining references on objects by this filp.
 558  */
 559 void
 560 drm_syncobj_release(struct drm_file *file_private)
 561 {
 562         idr_for_each(&file_private->syncobj_idr,
 563                      &drm_syncobj_release_handle, file_private);
 564         idr_destroy(&file_private->syncobj_idr);
 565 }
 566
 567 int
 568 drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
 569                          struct drm_file *file_private)
 570 {
 571         struct drm_syncobj_create *args = data;
 572
 573         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 574                 return -ENODEV;
 575
 576         /* no valid flags yet */
 577         if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
 578                 return -EINVAL;
 579
 580         return drm_syncobj_create_as_handle(file_private,
 581                                             &args->handle, args->flags);
 582 }
 583
 584 int
 585 drm_syncobj_destroy_ioctl(struct drm_device *dev, void *data,
 586                           struct drm_file *file_private)
 587 {
 588         struct drm_syncobj_destroy *args = data;
 589
 590         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 591                 return -ENODEV;
 592
 593         /* make sure padding is empty */
 594         if (args->pad)
 595                 return -EINVAL;
 596         return drm_syncobj_destroy(file_private, args->handle);
 597 }
 598
 599 int
 600 drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
 601                                    struct drm_file *file_private)
 602 {
 603         struct drm_syncobj_handle *args = data;
 604
 605         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 606                 return -ENODEV;
 607
 608         if (args->pad)
 609                 return -EINVAL;
 610
 611         if (args->flags != 0 &&
 612             args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
 613                 return -EINVAL;
 614
 615         if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
 616                 return drm_syncobj_export_sync_file(file_private, args->handle,
 617                                                     &args->fd);
 618
 619         return drm_syncobj_handle_to_fd(file_private, args->handle,
 620                                         &args->fd);
 621 }
 622
 623 int
 624 drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data,
 625                                    struct drm_file *file_private)
 626 {
 627         struct drm_syncobj_handle *args = data;
 628
 629         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 630                 return -ENODEV;
 631
 632         if (args->pad)
 633                 return -EINVAL;
 634
 635         if (args->flags != 0 &&
 636             args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
 637                 return -EINVAL;
 638
 639         if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
 640                 return drm_syncobj_import_sync_file_fence(file_private,
 641                                                           args->fd,
 642                                                           args->handle);
 643
 644         return drm_syncobj_fd_to_handle(file_private, args->fd,
 645                                         &args->handle);
 646 }
 647
 648 #if 0
 649 struct syncobj_wait_entry {
 650         struct task_struct *task;
 651         struct dma_fence *fence;
 652         struct dma_fence_cb fence_cb;
 653         struct drm_syncobj_cb syncobj_cb;
 654 };
 655
 656 static void syncobj_wait_fence_func(struct dma_fence *fence,
 657                                     struct dma_fence_cb *cb)
 658 {
 659         struct syncobj_wait_entry *wait =
 660                 container_of(cb, struct syncobj_wait_entry, fence_cb);
 661
 662         wake_up_process(wait->task);
 663 }
 664
 665 static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
 666                                       struct drm_syncobj_cb *cb)
 667 {
 668         struct syncobj_wait_entry *wait =
 669                 container_of(cb, struct syncobj_wait_entry, syncobj_cb);
 670
 671         /* This happens inside the syncobj lock */
 672         wait->fence = dma_fence_get(syncobj->fence);
 673         wake_up_process(wait->task);
 674 }
 675
 676 static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
 677                                                   uint32_t count,
 678                                                   uint32_t flags,
 679                                                   signed long timeout,
 680                                                   uint32_t *idx)
 681 {
 682         struct syncobj_wait_entry *entries;
 683         struct dma_fence *fence;
 684         signed long ret;
 685         uint32_t signaled_count, i;
 686
 687         entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
 688         if (!entries)
 689                 return -ENOMEM;
 690
 691         /* Walk the list of sync objects and initialize entries.  We do
 692          * this up-front so that we can properly return -EINVAL if there is
 693          * a syncobj with a missing fence and then never have the chance of
 694          * returning -EINVAL again.
 695          */
 696         signaled_count = 0;
 697         for (i = 0; i < count; ++i) {
 698                 entries[i].task = current;
 699                 entries[i].fence = drm_syncobj_fence_get(syncobjs[i]);
 700                 if (!entries[i].fence) {
 701                         if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
 702                                 continue;
 703                         } else {
 704                                 ret = -EINVAL;
 705                                 goto cleanup_entries;
 706                         }
 707                 }
 708
 709                 if (dma_fence_is_signaled(entries[i].fence)) {
 710                         if (signaled_count == 0 && idx)
 711                                 *idx = i;
 712                         signaled_count++;
 713                 }
 714         }
 715
 716         /* Initialize ret to the max of timeout and 1.  That way, the
 717          * default return value indicates a successful wait and not a
 718          * timeout.
 719          */
 720         ret = max_t(signed long, timeout, 1);
 721
 722         if (signaled_count == count ||
 723             (signaled_count > 0 &&
 724              !(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL)))
 725                 goto cleanup_entries;
 726
 727         /* There's a very annoying laxness in the dma_fence API here, in
 728          * that backends are not required to automatically report when a
 729          * fence is signaled prior to fence->ops->enable_signaling() being
 730          * called.  So here if we fail to match signaled_count, we need to
 731          * fallthough and try a 0 timeout wait!
 732          */
 733
 734         if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
 735                 for (i = 0; i < count; ++i) {
 736                         drm_syncobj_fence_get_or_add_callback(syncobjs[i],
 737                                                               &entries[i].fence,
 738                                                               &entries[i].syncobj_cb,
 739                                                               syncobj_wait_syncobj_func);
 740                 }
 741         }
 742
 743         do {
 744                 set_current_state(TASK_INTERRUPTIBLE);
 745
 746                 signaled_count = 0;
 747                 for (i = 0; i < count; ++i) {
 748                         fence = entries[i].fence;
 749                         if (!fence)
 750                                 continue;
 751
 752                         if (dma_fence_is_signaled(fence) ||
 753                             (!entries[i].fence_cb.func &&
 754                              dma_fence_add_callback(fence,
 755                                                     &entries[i].fence_cb,
 756                                                     syncobj_wait_fence_func))) {
 757                                 /* The fence has been signaled */
 758                                 if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) {
 759                                         signaled_count++;
 760                                 } else {
 761                                         if (idx)
 762                                                 *idx = i;
 763                                         goto done_waiting;
 764                                 }
 765                         }
 766                 }
 767
 768                 if (signaled_count == count)
 769                         goto done_waiting;
 770
 771                 if (timeout == 0) {
 772                         /* If we are doing a 0 timeout wait and we got
 773                          * here, then we just timed out.
 774                          */
 775                         ret = 0;
 776                         goto done_waiting;
 777                 }
 778
 779                 ret = schedule_timeout(ret);
 780
 781                 if (ret > 0 && signal_pending(current))
 782                         ret = -ERESTARTSYS;
 783         } while (ret > 0);
 784
 785 done_waiting:
 786         __set_current_state(TASK_RUNNING);
 787
 788 cleanup_entries:
 789         for (i = 0; i < count; ++i) {
 790                 if (entries[i].syncobj_cb.func)
 791                         drm_syncobj_remove_callback(syncobjs[i],
 792                                                     &entries[i].syncobj_cb);
 793                 if (entries[i].fence_cb.func)
 794                         dma_fence_remove_callback(entries[i].fence,
 795                                                   &entries[i].fence_cb);
 796                 dma_fence_put(entries[i].fence);
 797         }
 798         kfree(entries);
 799
 800         return ret;
 801 }
 802
 803 /**
 804  * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute value
 805  *
 806  * @timeout_nsec: timeout nsec component in ns, 0 for poll
 807  *
 808  * Calculate the timeout in jiffies from an absolute time in sec/nsec.
 809  */
 810 static signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec)
 811 {
 812         ktime_t abs_timeout, now;
 813         u64 timeout_ns, timeout_jiffies64;
 814
 815         /* make 0 timeout means poll - absolute 0 doesn't seem valid */
 816         if (timeout_nsec == 0)
 817                 return 0;
 818
 819         abs_timeout = ns_to_ktime(timeout_nsec);
 820         now = ktime_get();
 821
 822         if (!ktime_after(abs_timeout, now))
 823                 return 0;
 824
 825         timeout_ns = ktime_to_ns(ktime_sub(abs_timeout, now));
 826
 827         timeout_jiffies64 = nsecs_to_jiffies64(timeout_ns);
 828         /*  clamp timeout to avoid infinite timeout */
 829         if (timeout_jiffies64 >= MAX_SCHEDULE_TIMEOUT - 1)
 830                 return MAX_SCHEDULE_TIMEOUT - 1;
 831
 832         return timeout_jiffies64 + 1;
 833 }
 834
 835 static int drm_syncobj_array_wait(struct drm_device *dev,
 836                                   struct drm_file *file_private,
 837                                   struct drm_syncobj_wait *wait,
 838                                   struct drm_syncobj **syncobjs)
 839 {
 840         signed long timeout = drm_timeout_abs_to_jiffies(wait->timeout_nsec);
 841         signed long ret = 0;
 842         uint32_t first = ~0;
 843
 844         ret = drm_syncobj_array_wait_timeout(syncobjs,
 845                                              wait->count_handles,
 846                                              wait->flags,
 847                                              timeout, &first);
 848         if (ret < 0)
 849                 return ret;
 850
 851         wait->first_signaled = first;
 852         if (ret == 0)
 853                 return -ETIME;
 854         return 0;
 855 }
 856 #endif
 857
 858 static int drm_syncobj_array_find(struct drm_file *file_private,
 859                                   void __user *user_handles,
 860                                   uint32_t count_handles,
 861                                   struct drm_syncobj ***syncobjs_out)
 862 {
 863         uint32_t i, *handles;
 864         struct drm_syncobj **syncobjs;
 865         int ret;
 866
 867         handles = kmalloc_array(count_handles, sizeof(*handles), GFP_KERNEL);
 868         if (handles == NULL)
 869                 return -ENOMEM;
 870
 871         if (copy_from_user(handles, user_handles,
 872                            sizeof(uint32_t) * count_handles)) {
 873                 ret = -EFAULT;
 874                 goto err_free_handles;
 875         }
 876
 877         syncobjs = kmalloc_array(count_handles, sizeof(*syncobjs), GFP_KERNEL);
 878         if (syncobjs == NULL) {
 879                 ret = -ENOMEM;
 880                 goto err_free_handles;
 881         }
 882
 883         for (i = 0; i < count_handles; i++) {
 884                 syncobjs[i] = drm_syncobj_find(file_private, handles[i]);
 885                 if (!syncobjs[i]) {
 886                         ret = -ENOENT;
 887                         goto err_put_syncobjs;
 888                 }
 889         }
 890
 891         kfree(handles);
 892         *syncobjs_out = syncobjs;
 893         return 0;
 894
 895 err_put_syncobjs:
 896         while (i-- > 0)
 897                 drm_syncobj_put(syncobjs[i]);
 898         kfree(syncobjs);
 899 err_free_handles:
 900         kfree(handles);
 901
 902         return ret;
 903 }
 904
 905 static void drm_syncobj_array_free(struct drm_syncobj **syncobjs,
 906                                    uint32_t count)
 907 {
 908         uint32_t i;
 909         for (i = 0; i < count; i++)
 910                 drm_syncobj_put(syncobjs[i]);
 911         kfree(syncobjs);
 912 }
 913
 914 int
 915 drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
 916                        struct drm_file *file_private)
 917 {
 918 #if 0
 919         struct drm_syncobj_wait *args = data;
 920         struct drm_syncobj **syncobjs;
 921         int ret = 0;
 922
 923         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 924                 return -ENODEV;
 925
 926         if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
 927                             DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
 928                 return -EINVAL;
 929
 930         if (args->count_handles == 0)
 931                 return -EINVAL;
 932
 933         ret = drm_syncobj_array_find(file_private,
 934                                      u64_to_user_ptr(args->handles),
 935                                      args->count_handles,
 936                                      &syncobjs);
 937         if (ret < 0)
 938                 return ret;
 939
 940         ret = drm_syncobj_array_wait(dev, file_private,
 941                                      args, syncobjs);
 942
 943         drm_syncobj_array_free(syncobjs, args->count_handles);
 944
 945         return ret;
 946 #endif
 947         return -EINVAL;
 948 }
 949
 950 int
 951 drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
 952                         struct drm_file *file_private)
 953 {
 954         struct drm_syncobj_array *args = data;
 955         struct drm_syncobj **syncobjs;
 956         uint32_t i;
 957         int ret;
 958
 959         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 960                 return -ENODEV;
 961
 962         if (args->pad != 0)
 963                 return -EINVAL;
 964
 965         if (args->count_handles == 0)
 966                 return -EINVAL;
 967
 968         ret = drm_syncobj_array_find(file_private,
 969                                      u64_to_user_ptr(args->handles),
 970                                      args->count_handles,
 971                                      &syncobjs);
 972         if (ret < 0)
 973                 return ret;
 974
 975         for (i = 0; i < args->count_handles; i++)
 976                 drm_syncobj_replace_fence(syncobjs[i], NULL);
 977
 978         drm_syncobj_array_free(syncobjs, args->count_handles);
 979
 980         return 0;
 981 }
 982
 983 int
 984 drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,
 985                          struct drm_file *file_private)
 986 {
 987         struct drm_syncobj_array *args = data;
 988         struct drm_syncobj **syncobjs;
 989         uint32_t i;
 990         int ret;
 991
 992         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 993                 return -ENODEV;
 994
 995         if (args->pad != 0)
 996                 return -EINVAL;
 997
 998         if (args->count_handles == 0)
 999                 return -EINVAL;
1000
1001         ret = drm_syncobj_array_find(file_private,
1002                                      u64_to_user_ptr(args->handles),
1003                                      args->count_handles,
1004                                      &syncobjs);
1005         if (ret < 0)
1006                 return ret;
1007
1008         for (i = 0; i < args->count_handles; i++) {
1009                 ret = drm_syncobj_assign_null_handle(syncobjs[i]);
1010                 if (ret < 0)
1011                         break;
1012         }
1013
1014         drm_syncobj_array_free(syncobjs, args->count_handles);
1015
1016         return ret;
1017 }