drivers/gpu/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         spin_lock(&file_private->syncobj_table_lock);
  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         spin_unlock(&file_private->syncobj_table_lock);
  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 static int drm_syncobj_fence_get_or_add_callback(struct drm_syncobj *syncobj,
  93                                                  struct dma_fence **fence,
  94                                                  struct drm_syncobj_cb *cb,
  95                                                  drm_syncobj_func_t func)
  96 {
  97         int ret;
  98
  99         *fence = drm_syncobj_fence_get(syncobj);
 100         if (*fence)
 101                 return 1;
 102
 103         spin_lock(&syncobj->lock);
 104         /* We've already tried once to get a fence and failed.  Now that we
 105          * have the lock, try one more time just to be sure we don't add a
 106          * callback when a fence has already been set.
 107          */
 108         if (syncobj->fence) {
 109                 *fence = dma_fence_get(syncobj->fence);
 110                 ret = 1;
 111         } else {
 112                 *fence = NULL;
 113                 drm_syncobj_add_callback_locked(syncobj, cb, func);
 114                 ret = 0;
 115         }
 116         spin_unlock(&syncobj->lock);
 117
 118         return ret;
 119 }
 120
 121 /**
 122  * drm_syncobj_add_callback - adds a callback to syncobj::cb_list
 123  * @syncobj: Sync object to which to add the callback
 124  * @cb: Callback to add
 125  * @func: Func to use when initializing the drm_syncobj_cb struct
 126  *
 127  * This adds a callback to be called next time the fence is replaced
 128  */
 129 void drm_syncobj_add_callback(struct drm_syncobj *syncobj,
 130                               struct drm_syncobj_cb *cb,
 131                               drm_syncobj_func_t func)
 132 {
 133         spin_lock(&syncobj->lock);
 134         drm_syncobj_add_callback_locked(syncobj, cb, func);
 135         spin_unlock(&syncobj->lock);
 136 }
 137 EXPORT_SYMBOL(drm_syncobj_add_callback);
 138
 139 /**
 140  * drm_syncobj_add_callback - removes a callback to syncobj::cb_list
 141  * @syncobj: Sync object from which to remove the callback
 142  * @cb: Callback to remove
 143  */
 144 void drm_syncobj_remove_callback(struct drm_syncobj *syncobj,
 145                                  struct drm_syncobj_cb *cb)
 146 {
 147         spin_lock(&syncobj->lock);
 148         list_del_init(&cb->node);
 149         spin_unlock(&syncobj->lock);
 150 }
 151 EXPORT_SYMBOL(drm_syncobj_remove_callback);
 152
 153 /**
 154  * drm_syncobj_replace_fence - replace fence in a sync object.
 155  * @syncobj: Sync object to replace fence in
 156  * @fence: fence to install in sync file.
 157  *
 158  * This replaces the fence on a sync object.
 159  */
 160 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
 161                                struct dma_fence *fence)
 162 {
 163         struct dma_fence *old_fence;
 164         struct drm_syncobj_cb *cur, *tmp;
 165
 166         if (fence)
 167                 dma_fence_get(fence);
 168
 169         spin_lock(&syncobj->lock);
 170
 171         old_fence = syncobj->fence;
 172         syncobj->fence = fence;
 173
 174         if (fence != old_fence) {
 175                 list_for_each_entry_safe(cur, tmp, &syncobj->cb_list, node) {
 176                         list_del_init(&cur->node);
 177                         cur->func(syncobj, cur);
 178                 }
 179         }
 180
 181         spin_unlock(&syncobj->lock);
 182
 183         dma_fence_put(old_fence);
 184 }
 185 EXPORT_SYMBOL(drm_syncobj_replace_fence);
 186
 187 struct drm_syncobj_null_fence {
 188         struct dma_fence base;
 189         spinlock_t lock;
 190 };
 191
 192 static const char *drm_syncobj_null_fence_get_name(struct dma_fence *fence)
 193 {
 194         return "syncobjnull";
 195 }
 196
 197 static bool drm_syncobj_null_fence_enable_signaling(struct dma_fence *fence)
 198 {
 199     dma_fence_enable_sw_signaling(fence);
 200     return !dma_fence_is_signaled(fence);
 201 }
 202
 203 static const struct dma_fence_ops drm_syncobj_null_fence_ops = {
 204         .get_driver_name = drm_syncobj_null_fence_get_name,
 205         .get_timeline_name = drm_syncobj_null_fence_get_name,
 206         .enable_signaling = drm_syncobj_null_fence_enable_signaling,
 207         .wait = dma_fence_default_wait,
 208         .release = NULL,
 209 };
 210
 211 static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
 212 {
 213         struct drm_syncobj_null_fence *fence;
 214         fence = kzalloc(sizeof(*fence), GFP_KERNEL);
 215         if (fence == NULL)
 216                 return -ENOMEM;
 217
 218         spin_lock_init(&fence->lock);
 219         dma_fence_init(&fence->base, &drm_syncobj_null_fence_ops,
 220                        &fence->lock, 0, 0);
 221         dma_fence_signal(&fence->base);
 222
 223         drm_syncobj_replace_fence(syncobj, &fence->base);
 224
 225         dma_fence_put(&fence->base);
 226
 227         return 0;
 228 }
 229
 230 int drm_syncobj_find_fence(struct drm_file *file_private,
 231                            u32 handle,
 232                            struct dma_fence **fence)
 233 {
 234         struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
 235         int ret = 0;
 236
 237         if (!syncobj)
 238                 return -ENOENT;
 239
 240         *fence = drm_syncobj_fence_get(syncobj);
 241         if (!*fence) {
 242                 ret = -EINVAL;
 243         }
 244         drm_syncobj_put(syncobj);
 245         return ret;
 246 }
 247 EXPORT_SYMBOL(drm_syncobj_find_fence);
 248
 249 /**
 250  * drm_syncobj_free - free a sync object.
 251  * @kref: kref to free.
 252  *
 253  * Only to be called from kref_put in drm_syncobj_put.
 254  */
 255 void drm_syncobj_free(struct kref *kref)
 256 {
 257         struct drm_syncobj *syncobj = container_of(kref,
 258                                                    struct drm_syncobj,
 259                                                    refcount);
 260         drm_syncobj_replace_fence(syncobj, NULL);
 261         kfree(syncobj);
 262 }
 263 EXPORT_SYMBOL(drm_syncobj_free);
 264
 265 /**
 266  * drm_syncobj_create - create a new syncobj
 267  * @out_syncobj: returned syncobj
 268  * @flags: DRM_SYNCOBJ_* flags
 269  * @fence: if non-NULL, the syncobj will represent this fence
 270  */
 271 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 272                        struct dma_fence *fence)
 273 {
 274         int ret;
 275         struct drm_syncobj *syncobj;
 276
 277         syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);
 278         if (!syncobj)
 279                 return -ENOMEM;
 280
 281         kref_init(&syncobj->refcount);
 282         INIT_LIST_HEAD(&syncobj->cb_list);
 283         spin_lock_init(&syncobj->lock);
 284
 285         if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
 286                 ret = drm_syncobj_assign_null_handle(syncobj);
 287                 if (ret < 0) {
 288                         drm_syncobj_put(syncobj);
 289                         return ret;
 290                 }
 291         }
 292
 293         if (fence)
 294                 drm_syncobj_replace_fence(syncobj, fence);
 295
 296         *out_syncobj = syncobj;
 297         return 0;
 298 }
 299 EXPORT_SYMBOL(drm_syncobj_create);
 300
 301 /**
 302  * drm_syncobj_get_handle - get a handle from a syncobj
 303  */
 304 int drm_syncobj_get_handle(struct drm_file *file_private,
 305                            struct drm_syncobj *syncobj, u32 *handle)
 306 {
 307         int ret;
 308
 309         /* take a reference to put in the idr */
 310         drm_syncobj_get(syncobj);
 311
 312         idr_preload(GFP_KERNEL);
 313         spin_lock(&file_private->syncobj_table_lock);
 314         ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
 315         spin_unlock(&file_private->syncobj_table_lock);
 316
 317         idr_preload_end();
 318
 319         if (ret < 0) {
 320                 drm_syncobj_put(syncobj);
 321                 return ret;
 322         }
 323
 324         *handle = ret;
 325         return 0;
 326 }
 327 EXPORT_SYMBOL(drm_syncobj_get_handle);
 328
 329 static int drm_syncobj_create_as_handle(struct drm_file *file_private,
 330                                         u32 *handle, uint32_t flags)
 331 {
 332         int ret;
 333         struct drm_syncobj *syncobj;
 334
 335         ret = drm_syncobj_create(&syncobj, flags, NULL);
 336         if (ret)
 337                 return ret;
 338
 339         ret = drm_syncobj_get_handle(file_private, syncobj, handle);
 340         drm_syncobj_put(syncobj);
 341         return ret;
 342 }
 343
 344 static int drm_syncobj_destroy(struct drm_file *file_private,
 345                                u32 handle)
 346 {
 347         struct drm_syncobj *syncobj;
 348
 349         spin_lock(&file_private->syncobj_table_lock);
 350         syncobj = idr_remove(&file_private->syncobj_idr, handle);
 351         spin_unlock(&file_private->syncobj_table_lock);
 352
 353         if (!syncobj)
 354                 return -EINVAL;
 355
 356         drm_syncobj_put(syncobj);
 357         return 0;
 358 }
 359
 360 static int drm_syncobj_file_release(struct inode *inode, struct file *file)
 361 {
 362         struct drm_syncobj *syncobj = file->private_data;
 363
 364         drm_syncobj_put(syncobj);
 365         return 0;
 366 }
 367
 368 static const struct file_operations drm_syncobj_file_fops = {
 369         .release = drm_syncobj_file_release,
 370 };
 371
 372 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
 373 {
 374         struct file *file;
 375         int fd;
 376
 377         fd = get_unused_fd_flags(O_CLOEXEC);
 378         if (fd < 0)
 379                 return fd;
 380
 381         file = anon_inode_getfile("syncobj_file",
 382                                   &drm_syncobj_file_fops,
 383                                   syncobj, 0);
 384         if (IS_ERR(file)) {
 385                 put_unused_fd(fd);
 386                 return PTR_ERR(file);
 387         }
 388
 389         drm_syncobj_get(syncobj);
 390         fd_install(fd, file);
 391
 392         *p_fd = fd;
 393         return 0;
 394 }
 395 EXPORT_SYMBOL(drm_syncobj_get_fd);
 396
 397 static int drm_syncobj_handle_to_fd(struct drm_file *file_private,
 398                                     u32 handle, int *p_fd)
 399 {
 400         struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
 401         int ret;
 402
 403         if (!syncobj)
 404                 return -EINVAL;
 405
 406         ret = drm_syncobj_get_fd(syncobj, p_fd);
 407         drm_syncobj_put(syncobj);
 408         return ret;
 409 }
 410
 411 static int drm_syncobj_fd_to_handle(struct drm_file *file_private,
 412                                     int fd, u32 *handle)
 413 {
 414         struct drm_syncobj *syncobj;
 415         struct file *file;
 416         int ret;
 417
 418         file = fget(fd);
 419         if (!file)
 420                 return -EINVAL;
 421
 422         if (file->f_op != &drm_syncobj_file_fops) {
 423                 fput(file);
 424                 return -EINVAL;
 425         }
 426
 427         /* take a reference to put in the idr */
 428         syncobj = file->private_data;
 429         drm_syncobj_get(syncobj);
 430
 431         idr_preload(GFP_KERNEL);
 432         spin_lock(&file_private->syncobj_table_lock);
 433         ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
 434         spin_unlock(&file_private->syncobj_table_lock);
 435         idr_preload_end();
 436
 437         if (ret > 0) {
 438                 *handle = ret;
 439                 ret = 0;
 440         } else
 441                 drm_syncobj_put(syncobj);
 442
 443         fput(file);
 444         return ret;
 445 }
 446
 447 static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
 448                                               int fd, int handle)
 449 {
 450         struct dma_fence *fence = sync_file_get_fence(fd);
 451         struct drm_syncobj *syncobj;
 452
 453         if (!fence)
 454                 return -EINVAL;
 455
 456         syncobj = drm_syncobj_find(file_private, handle);
 457         if (!syncobj) {
 458                 dma_fence_put(fence);
 459                 return -ENOENT;
 460         }
 461
 462         drm_syncobj_replace_fence(syncobj, fence);
 463         dma_fence_put(fence);
 464         drm_syncobj_put(syncobj);
 465         return 0;
 466 }
 467
 468 static int drm_syncobj_export_sync_file(struct drm_file *file_private,
 469                                         int handle, int *p_fd)
 470 {
 471         int ret;
 472         struct dma_fence *fence;
 473         struct sync_file *sync_file;
 474         int fd = get_unused_fd_flags(O_CLOEXEC);
 475
 476         if (fd < 0)
 477                 return fd;
 478
 479         ret = drm_syncobj_find_fence(file_private, handle, &fence);
 480         if (ret)
 481                 goto err_put_fd;
 482
 483         sync_file = sync_file_create(fence);
 484
 485         dma_fence_put(fence);
 486
 487         if (!sync_file) {
 488                 ret = -EINVAL;
 489                 goto err_put_fd;
 490         }
 491
 492         fd_install(fd, sync_file->file);
 493
 494         *p_fd = fd;
 495         return 0;
 496 err_put_fd:
 497         put_unused_fd(fd);
 498         return ret;
 499 }
 500 /**
 501  * drm_syncobj_open - initalizes syncobj file-private structures at devnode open time
 502  * @file_private: drm file-private structure to set up
 503  *
 504  * Called at device open time, sets up the structure for handling refcounting
 505  * of sync objects.
 506  */
 507 void
 508 drm_syncobj_open(struct drm_file *file_private)
 509 {
 510         idr_init(&file_private->syncobj_idr);
 511         spin_lock_init(&file_private->syncobj_table_lock);
 512 }
 513
 514 static int
 515 drm_syncobj_release_handle(int id, void *ptr, void *data)
 516 {
 517         struct drm_syncobj *syncobj = ptr;
 518
 519         drm_syncobj_put(syncobj);
 520         return 0;
 521 }
 522
 523 /**
 524  * drm_syncobj_release - release file-private sync object resources
 525  * @file_private: drm file-private structure to clean up
 526  *
 527  * Called at close time when the filp is going away.
 528  *
 529  * Releases any remaining references on objects by this filp.
 530  */
 531 void
 532 drm_syncobj_release(struct drm_file *file_private)
 533 {
 534         idr_for_each(&file_private->syncobj_idr,
 535                      &drm_syncobj_release_handle, file_private);
 536         idr_destroy(&file_private->syncobj_idr);
 537 }
 538
 539 int
 540 drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
 541                          struct drm_file *file_private)
 542 {
 543         struct drm_syncobj_create *args = data;
 544
 545         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 546                 return -ENODEV;
 547
 548         /* no valid flags yet */
 549         if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
 550                 return -EINVAL;
 551
 552         return drm_syncobj_create_as_handle(file_private,
 553                                             &args->handle, args->flags);
 554 }
 555
 556 int
 557 drm_syncobj_destroy_ioctl(struct drm_device *dev, void *data,
 558                           struct drm_file *file_private)
 559 {
 560         struct drm_syncobj_destroy *args = data;
 561
 562         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 563                 return -ENODEV;
 564
 565         /* make sure padding is empty */
 566         if (args->pad)
 567                 return -EINVAL;
 568         return drm_syncobj_destroy(file_private, args->handle);
 569 }
 570
 571 int
 572 drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
 573                                    struct drm_file *file_private)
 574 {
 575         struct drm_syncobj_handle *args = data;
 576
 577         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 578                 return -ENODEV;
 579
 580         if (args->pad)
 581                 return -EINVAL;
 582
 583         if (args->flags != 0 &&
 584             args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
 585                 return -EINVAL;
 586
 587         if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
 588                 return drm_syncobj_export_sync_file(file_private, args->handle,
 589                                                     &args->fd);
 590
 591         return drm_syncobj_handle_to_fd(file_private, args->handle,
 592                                         &args->fd);
 593 }
 594
 595 int
 596 drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data,
 597                                    struct drm_file *file_private)
 598 {
 599         struct drm_syncobj_handle *args = data;
 600
 601         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 602                 return -ENODEV;
 603
 604         if (args->pad)
 605                 return -EINVAL;
 606
 607         if (args->flags != 0 &&
 608             args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
 609                 return -EINVAL;
 610
 611         if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
 612                 return drm_syncobj_import_sync_file_fence(file_private,
 613                                                           args->fd,
 614                                                           args->handle);
 615
 616         return drm_syncobj_fd_to_handle(file_private, args->fd,
 617                                         &args->handle);
 618 }
 619
 620 struct syncobj_wait_entry {
 621         struct task_struct *task;
 622         struct dma_fence *fence;
 623         struct dma_fence_cb fence_cb;
 624         struct drm_syncobj_cb syncobj_cb;
 625 };
 626
 627 static void syncobj_wait_fence_func(struct dma_fence *fence,
 628                                     struct dma_fence_cb *cb)
 629 {
 630         struct syncobj_wait_entry *wait =
 631                 container_of(cb, struct syncobj_wait_entry, fence_cb);
 632
 633         wake_up_process(wait->task);
 634 }
 635
 636 static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
 637                                       struct drm_syncobj_cb *cb)
 638 {
 639         struct syncobj_wait_entry *wait =
 640                 container_of(cb, struct syncobj_wait_entry, syncobj_cb);
 641
 642         /* This happens inside the syncobj lock */
 643         wait->fence = dma_fence_get(syncobj->fence);
 644         wake_up_process(wait->task);
 645 }
 646
 647 static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
 648                                                   uint32_t count,
 649                                                   uint32_t flags,
 650                                                   signed long timeout,
 651                                                   uint32_t *idx)
 652 {
 653         struct syncobj_wait_entry *entries;
 654         struct dma_fence *fence;
 655         signed long ret;
 656         uint32_t signaled_count, i;
 657
 658         entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
 659         if (!entries)
 660                 return -ENOMEM;
 661
 662         /* Walk the list of sync objects and initialize entries.  We do
 663          * this up-front so that we can properly return -EINVAL if there is
 664          * a syncobj with a missing fence and then never have the chance of
 665          * returning -EINVAL again.
 666          */
 667         signaled_count = 0;
 668         for (i = 0; i < count; ++i) {
 669                 entries[i].task = current;
 670                 entries[i].fence = drm_syncobj_fence_get(syncobjs[i]);
 671                 if (!entries[i].fence) {
 672                         if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
 673                                 continue;
 674                         } else {
 675                                 ret = -EINVAL;
 676                                 goto cleanup_entries;
 677                         }
 678                 }
 679
 680                 if (dma_fence_is_signaled(entries[i].fence)) {
 681                         if (signaled_count == 0 && idx)
 682                                 *idx = i;
 683                         signaled_count++;
 684                 }
 685         }
 686
 687         /* Initialize ret to the max of timeout and 1.  That way, the
 688          * default return value indicates a successful wait and not a
 689          * timeout.
 690          */
 691         ret = max_t(signed long, timeout, 1);
 692
 693         if (signaled_count == count ||
 694             (signaled_count > 0 &&
 695              !(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL)))
 696                 goto cleanup_entries;
 697
 698         /* There's a very annoying laxness in the dma_fence API here, in
 699          * that backends are not required to automatically report when a
 700          * fence is signaled prior to fence->ops->enable_signaling() being
 701          * called.  So here if we fail to match signaled_count, we need to
 702          * fallthough and try a 0 timeout wait!
 703          */
 704
 705         if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
 706                 for (i = 0; i < count; ++i) {
 707                         drm_syncobj_fence_get_or_add_callback(syncobjs[i],
 708                                                               &entries[i].fence,
 709                                                               &entries[i].syncobj_cb,
 710                                                               syncobj_wait_syncobj_func);
 711                 }
 712         }
 713
 714         do {
 715                 set_current_state(TASK_INTERRUPTIBLE);
 716
 717                 signaled_count = 0;
 718                 for (i = 0; i < count; ++i) {
 719                         fence = entries[i].fence;
 720                         if (!fence)
 721                                 continue;
 722
 723                         if (dma_fence_is_signaled(fence) ||
 724                             (!entries[i].fence_cb.func &&
 725                              dma_fence_add_callback(fence,
 726                                                     &entries[i].fence_cb,
 727                                                     syncobj_wait_fence_func))) {
 728                                 /* The fence has been signaled */
 729                                 if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) {
 730                                         signaled_count++;
 731                                 } else {
 732                                         if (idx)
 733                                                 *idx = i;
 734                                         goto done_waiting;
 735                                 }
 736                         }
 737                 }
 738
 739                 if (signaled_count == count)
 740                         goto done_waiting;
 741
 742                 if (timeout == 0) {
 743                         /* If we are doing a 0 timeout wait and we got
 744                          * here, then we just timed out.
 745                          */
 746                         ret = 0;
 747                         goto done_waiting;
 748                 }
 749
 750                 ret = schedule_timeout(ret);
 751
 752                 if (ret > 0 && signal_pending(current))
 753                         ret = -ERESTARTSYS;
 754         } while (ret > 0);
 755
 756 done_waiting:
 757         __set_current_state(TASK_RUNNING);
 758
 759 cleanup_entries:
 760         for (i = 0; i < count; ++i) {
 761                 if (entries[i].syncobj_cb.func)
 762                         drm_syncobj_remove_callback(syncobjs[i],
 763                                                     &entries[i].syncobj_cb);
 764                 if (entries[i].fence_cb.func)
 765                         dma_fence_remove_callback(entries[i].fence,
 766                                                   &entries[i].fence_cb);
 767                 dma_fence_put(entries[i].fence);
 768         }
 769         kfree(entries);
 770
 771         return ret;
 772 }
 773
 774 /**
 775  * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute value
 776  *
 777  * @timeout_nsec: timeout nsec component in ns, 0 for poll
 778  *
 779  * Calculate the timeout in jiffies from an absolute time in sec/nsec.
 780  */
 781 static signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec)
 782 {
 783         ktime_t abs_timeout, now;
 784         u64 timeout_ns, timeout_jiffies64;
 785
 786         /* make 0 timeout means poll - absolute 0 doesn't seem valid */
 787         if (timeout_nsec == 0)
 788                 return 0;
 789
 790         abs_timeout = ns_to_ktime(timeout_nsec);
 791         now = ktime_get();
 792
 793         if (!ktime_after(abs_timeout, now))
 794                 return 0;
 795
 796         timeout_ns = ktime_to_ns(ktime_sub(abs_timeout, now));
 797
 798         timeout_jiffies64 = nsecs_to_jiffies64(timeout_ns);
 799         /*  clamp timeout to avoid infinite timeout */
 800         if (timeout_jiffies64 >= MAX_SCHEDULE_TIMEOUT - 1)
 801                 return MAX_SCHEDULE_TIMEOUT - 1;
 802
 803         return timeout_jiffies64 + 1;
 804 }
 805
 806 static int drm_syncobj_array_wait(struct drm_device *dev,
 807                                   struct drm_file *file_private,
 808                                   struct drm_syncobj_wait *wait,
 809                                   struct drm_syncobj **syncobjs)
 810 {
 811         signed long timeout = drm_timeout_abs_to_jiffies(wait->timeout_nsec);
 812         signed long ret = 0;
 813         uint32_t first = ~0;
 814
 815         ret = drm_syncobj_array_wait_timeout(syncobjs,
 816                                              wait->count_handles,
 817                                              wait->flags,
 818                                              timeout, &first);
 819         if (ret < 0)
 820                 return ret;
 821
 822         wait->first_signaled = first;
 823         if (ret == 0)
 824                 return -ETIME;
 825         return 0;
 826 }
 827
 828 static int drm_syncobj_array_find(struct drm_file *file_private,
 829                                   void __user *user_handles,
 830                                   uint32_t count_handles,
 831                                   struct drm_syncobj ***syncobjs_out)
 832 {
 833         uint32_t i, *handles;
 834         struct drm_syncobj **syncobjs;
 835         int ret;
 836
 837         handles = kmalloc_array(count_handles, sizeof(*handles), GFP_KERNEL);
 838         if (handles == NULL)
 839                 return -ENOMEM;
 840
 841         if (copy_from_user(handles, user_handles,
 842                            sizeof(uint32_t) * count_handles)) {
 843                 ret = -EFAULT;
 844                 goto err_free_handles;
 845         }
 846
 847         syncobjs = kmalloc_array(count_handles, sizeof(*syncobjs), GFP_KERNEL);
 848         if (syncobjs == NULL) {
 849                 ret = -ENOMEM;
 850                 goto err_free_handles;
 851         }
 852
 853         for (i = 0; i < count_handles; i++) {
 854                 syncobjs[i] = drm_syncobj_find(file_private, handles[i]);
 855                 if (!syncobjs[i]) {
 856                         ret = -ENOENT;
 857                         goto err_put_syncobjs;
 858                 }
 859         }
 860
 861         kfree(handles);
 862         *syncobjs_out = syncobjs;
 863         return 0;
 864
 865 err_put_syncobjs:
 866         while (i-- > 0)
 867                 drm_syncobj_put(syncobjs[i]);
 868         kfree(syncobjs);
 869 err_free_handles:
 870         kfree(handles);
 871
 872         return ret;
 873 }
 874
 875 static void drm_syncobj_array_free(struct drm_syncobj **syncobjs,
 876                                    uint32_t count)
 877 {
 878         uint32_t i;
 879         for (i = 0; i < count; i++)
 880                 drm_syncobj_put(syncobjs[i]);
 881         kfree(syncobjs);
 882 }
 883
 884 int
 885 drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
 886                        struct drm_file *file_private)
 887 {
 888         struct drm_syncobj_wait *args = data;
 889         struct drm_syncobj **syncobjs;
 890         int ret = 0;
 891
 892         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 893                 return -ENODEV;
 894
 895         if (args->flags & ~(DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
 896                             DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
 897                 return -EINVAL;
 898
 899         if (args->count_handles == 0)
 900                 return -EINVAL;
 901
 902         ret = drm_syncobj_array_find(file_private,
 903                                      u64_to_user_ptr(args->handles),
 904                                      args->count_handles,
 905                                      &syncobjs);
 906         if (ret < 0)
 907                 return ret;
 908
 909         ret = drm_syncobj_array_wait(dev, file_private,
 910                                      args, syncobjs);
 911
 912         drm_syncobj_array_free(syncobjs, args->count_handles);
 913
 914         return ret;
 915 }
 916
 917 int
 918 drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
 919                         struct drm_file *file_private)
 920 {
 921         struct drm_syncobj_array *args = data;
 922         struct drm_syncobj **syncobjs;
 923         uint32_t i;
 924         int ret;
 925
 926         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 927                 return -ENODEV;
 928
 929         if (args->pad != 0)
 930                 return -EINVAL;
 931
 932         if (args->count_handles == 0)
 933                 return -EINVAL;
 934
 935         ret = drm_syncobj_array_find(file_private,
 936                                      u64_to_user_ptr(args->handles),
 937                                      args->count_handles,
 938                                      &syncobjs);
 939         if (ret < 0)
 940                 return ret;
 941
 942         for (i = 0; i < args->count_handles; i++)
 943                 drm_syncobj_replace_fence(syncobjs[i], NULL);
 944
 945         drm_syncobj_array_free(syncobjs, args->count_handles);
 946
 947         return 0;
 948 }
 949
 950 int
 951 drm_syncobj_signal_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                 ret = drm_syncobj_assign_null_handle(syncobjs[i]);
 977                 if (ret < 0)
 978                         break;
 979         }
 980
 981         drm_syncobj_array_free(syncobjs, args->count_handles);
 982
 983         return ret;
 984 }