drivers/staging/android/sync.c

   1 /*
   2  * drivers/base/sync.c
   3  *
   4  * Copyright (C) 2012 Google, Inc.
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  */
  16
  17 #include <linux/debugfs.h>
  18 #include <linux/export.h>
  19 #include <linux/file.h>
  20 #include <linux/fs.h>
  21 #include <linux/kernel.h>
  22 #include <linux/poll.h>
  23 #include <linux/sched.h>
  24 #include <linux/seq_file.h>
  25 #include <linux/slab.h>
  26 #include <linux/uaccess.h>
  27 #include <linux/anon_inodes.h>
  28
  29 #include "sync.h"
  30
  31 #define CREATE_TRACE_POINTS
  32 #include "trace/sync.h"
  33
  34 static void sync_fence_signal_pt(struct sync_pt *pt);
  35 static int _sync_pt_has_signaled(struct sync_pt *pt);
  36 static void sync_fence_free(struct kref *kref);
  37 static void sync_dump(void);
  38
  39 static LIST_HEAD(sync_timeline_list_head);
  40 static DEFINE_SPINLOCK(sync_timeline_list_lock);
  41
  42 static LIST_HEAD(sync_fence_list_head);
  43 static DEFINE_SPINLOCK(sync_fence_list_lock);
  44
  45 struct sync_timeline *sync_timeline_create(const struct sync_timeline_ops *ops,
  46                                            int size, const char *name)
  47 {
  48         struct sync_timeline *obj;
  49         unsigned long flags;
  50
  51         if (size < sizeof(struct sync_timeline))
  52                 return NULL;
  53
  54         obj = kzalloc(size, GFP_KERNEL);
  55         if (obj == NULL)
  56                 return NULL;
  57
  58         kref_init(&obj->kref);
  59         obj->ops = ops;
  60         strlcpy(obj->name, name, sizeof(obj->name));
  61
  62         INIT_LIST_HEAD(&obj->child_list_head);
  63         spin_lock_init(&obj->child_list_lock);
  64
  65         INIT_LIST_HEAD(&obj->active_list_head);
  66         spin_lock_init(&obj->active_list_lock);
  67
  68         spin_lock_irqsave(&sync_timeline_list_lock, flags);
  69         list_add_tail(&obj->sync_timeline_list, &sync_timeline_list_head);
  70         spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
  71
  72         return obj;
  73 }
  74 EXPORT_SYMBOL(sync_timeline_create);
  75
  76 static void sync_timeline_free(struct kref *kref)
  77 {
  78         struct sync_timeline *obj =
  79                 container_of(kref, struct sync_timeline, kref);
  80         unsigned long flags;
  81
  82         spin_lock_irqsave(&sync_timeline_list_lock, flags);
  83         list_del(&obj->sync_timeline_list);
  84         spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
  85
  86         if (obj->ops->release_obj)
  87                 obj->ops->release_obj(obj);
  88
  89         kfree(obj);
  90 }
  91
  92 void sync_timeline_destroy(struct sync_timeline *obj)
  93 {
  94         obj->destroyed = true;
  95         /*
  96          * Ensure timeline is marked as destroyed before
  97          * changing timeline's fences status.
  98          */
  99         smp_wmb();
 100
 101         /*
 102          * signal any children that their parent is going away.
 103          */
 104         sync_timeline_signal(obj);
 105
 106         kref_put(&obj->kref, sync_timeline_free);
 107 }
 108 EXPORT_SYMBOL(sync_timeline_destroy);
 109
 110 static void sync_timeline_add_pt(struct sync_timeline *obj, struct sync_pt *pt)
 111 {
 112         unsigned long flags;
 113
 114         pt->parent = obj;
 115
 116         spin_lock_irqsave(&obj->child_list_lock, flags);
 117         list_add_tail(&pt->child_list, &obj->child_list_head);
 118         spin_unlock_irqrestore(&obj->child_list_lock, flags);
 119 }
 120
 121 static void sync_timeline_remove_pt(struct sync_pt *pt)
 122 {
 123         struct sync_timeline *obj = pt->parent;
 124         unsigned long flags;
 125
 126         spin_lock_irqsave(&obj->active_list_lock, flags);
 127         if (!list_empty(&pt->active_list))
 128                 list_del_init(&pt->active_list);
 129         spin_unlock_irqrestore(&obj->active_list_lock, flags);
 130
 131         spin_lock_irqsave(&obj->child_list_lock, flags);
 132         if (!list_empty(&pt->child_list))
 133                 list_del_init(&pt->child_list);
 134
 135         spin_unlock_irqrestore(&obj->child_list_lock, flags);
 136 }
 137
 138 void sync_timeline_signal(struct sync_timeline *obj)
 139 {
 140         unsigned long flags;
 141         LIST_HEAD(signaled_pts);
 142         struct list_head *pos, *n;
 143
 144         trace_sync_timeline(obj);
 145
 146         spin_lock_irqsave(&obj->active_list_lock, flags);
 147
 148         list_for_each_safe(pos, n, &obj->active_list_head) {
 149                 struct sync_pt *pt =
 150                         container_of(pos, struct sync_pt, active_list);
 151
 152                 if (_sync_pt_has_signaled(pt)) {
 153                         list_del_init(pos);
 154                         list_add(&pt->signaled_list, &signaled_pts);
 155                         kref_get(&pt->fence->kref);
 156                 }
 157         }
 158
 159         spin_unlock_irqrestore(&obj->active_list_lock, flags);
 160
 161         list_for_each_safe(pos, n, &signaled_pts) {
 162                 struct sync_pt *pt =
 163                         container_of(pos, struct sync_pt, signaled_list);
 164
 165                 list_del_init(pos);
 166                 sync_fence_signal_pt(pt);
 167                 kref_put(&pt->fence->kref, sync_fence_free);
 168         }
 169 }
 170 EXPORT_SYMBOL(sync_timeline_signal);
 171
 172 struct sync_pt *sync_pt_create(struct sync_timeline *parent, int size)
 173 {
 174         struct sync_pt *pt;
 175
 176         if (size < sizeof(struct sync_pt))
 177                 return NULL;
 178
 179         pt = kzalloc(size, GFP_KERNEL);
 180         if (pt == NULL)
 181                 return NULL;
 182
 183         INIT_LIST_HEAD(&pt->active_list);
 184         kref_get(&parent->kref);
 185         sync_timeline_add_pt(parent, pt);
 186
 187         return pt;
 188 }
 189 EXPORT_SYMBOL(sync_pt_create);
 190
 191 void sync_pt_free(struct sync_pt *pt)
 192 {
 193         if (pt->parent->ops->free_pt)
 194                 pt->parent->ops->free_pt(pt);
 195
 196         sync_timeline_remove_pt(pt);
 197
 198         kref_put(&pt->parent->kref, sync_timeline_free);
 199
 200         kfree(pt);
 201 }
 202 EXPORT_SYMBOL(sync_pt_free);
 203
 204 /* call with pt->parent->active_list_lock held */
 205 static int _sync_pt_has_signaled(struct sync_pt *pt)
 206 {
 207         int old_status = pt->status;
 208
 209         if (!pt->status)
 210                 pt->status = pt->parent->ops->has_signaled(pt);
 211
 212         if (!pt->status && pt->parent->destroyed)
 213                 pt->status = -ENOENT;
 214
 215         if (pt->status != old_status)
 216                 pt->timestamp = ktime_get();
 217
 218         return pt->status;
 219 }
 220
 221 static struct sync_pt *sync_pt_dup(struct sync_pt *pt)
 222 {
 223         return pt->parent->ops->dup(pt);
 224 }
 225
 226 /* Adds a sync pt to the active queue.  Called when added to a fence */
 227 static void sync_pt_activate(struct sync_pt *pt)
 228 {
 229         struct sync_timeline *obj = pt->parent;
 230         unsigned long flags;
 231         int err;
 232
 233         spin_lock_irqsave(&obj->active_list_lock, flags);
 234
 235         err = _sync_pt_has_signaled(pt);
 236         if (err != 0)
 237                 goto out;
 238
 239         list_add_tail(&pt->active_list, &obj->active_list_head);
 240
 241 out:
 242         spin_unlock_irqrestore(&obj->active_list_lock, flags);
 243 }
 244
 245 static int sync_fence_release(struct inode *inode, struct file *file);
 246 static unsigned int sync_fence_poll(struct file *file, poll_table *wait);
 247 static long sync_fence_ioctl(struct file *file, unsigned int cmd,
 248                              unsigned long arg);
 249
 250
 251 static const struct file_operations sync_fence_fops = {
 252         .release = sync_fence_release,
 253         .poll = sync_fence_poll,
 254         .unlocked_ioctl = sync_fence_ioctl,
 255         .compat_ioctl = sync_fence_ioctl,
 256 };
 257
 258 static struct sync_fence *sync_fence_alloc(const char *name)
 259 {
 260         struct sync_fence *fence;
 261         unsigned long flags;
 262
 263         fence = kzalloc(sizeof(struct sync_fence), GFP_KERNEL);
 264         if (fence == NULL)
 265                 return NULL;
 266
 267         fence->file = anon_inode_getfile("sync_fence", &sync_fence_fops,
 268                                          fence, 0);
 269         if (IS_ERR(fence->file))
 270                 goto err;
 271
 272         kref_init(&fence->kref);
 273         strlcpy(fence->name, name, sizeof(fence->name));
 274
 275         INIT_LIST_HEAD(&fence->pt_list_head);
 276         INIT_LIST_HEAD(&fence->waiter_list_head);
 277         spin_lock_init(&fence->waiter_list_lock);
 278
 279         init_waitqueue_head(&fence->wq);
 280
 281         spin_lock_irqsave(&sync_fence_list_lock, flags);
 282         list_add_tail(&fence->sync_fence_list, &sync_fence_list_head);
 283         spin_unlock_irqrestore(&sync_fence_list_lock, flags);
 284
 285         return fence;
 286
 287 err:
 288         kfree(fence);
 289         return NULL;
 290 }
 291
 292 /* TODO: implement a create which takes more that one sync_pt */
 293 struct sync_fence *sync_fence_create(const char *name, struct sync_pt *pt)
 294 {
 295         struct sync_fence *fence;
 296
 297         if (pt->fence)
 298                 return NULL;
 299
 300         fence = sync_fence_alloc(name);
 301         if (fence == NULL)
 302                 return NULL;
 303
 304         pt->fence = fence;
 305         list_add(&pt->pt_list, &fence->pt_list_head);
 306         sync_pt_activate(pt);
 307
 308         /*
 309          * signal the fence in case pt was activated before
 310          * sync_pt_activate(pt) was called
 311          */
 312         sync_fence_signal_pt(pt);
 313
 314         return fence;
 315 }
 316 EXPORT_SYMBOL(sync_fence_create);
 317
 318 static int sync_fence_copy_pts(struct sync_fence *dst, struct sync_fence *src)
 319 {
 320         struct list_head *pos;
 321
 322         list_for_each(pos, &src->pt_list_head) {
 323                 struct sync_pt *orig_pt =
 324                         container_of(pos, struct sync_pt, pt_list);
 325                 struct sync_pt *new_pt = sync_pt_dup(orig_pt);
 326
 327                 if (new_pt == NULL)
 328                         return -ENOMEM;
 329
 330                 new_pt->fence = dst;
 331                 list_add(&new_pt->pt_list, &dst->pt_list_head);
 332         }
 333
 334         return 0;
 335 }
 336
 337 static int sync_fence_merge_pts(struct sync_fence *dst, struct sync_fence *src)
 338 {
 339         struct list_head *src_pos, *dst_pos, *n;
 340
 341         list_for_each(src_pos, &src->pt_list_head) {
 342                 struct sync_pt *src_pt =
 343                         container_of(src_pos, struct sync_pt, pt_list);
 344                 bool collapsed = false;
 345
 346                 list_for_each_safe(dst_pos, n, &dst->pt_list_head) {
 347                         struct sync_pt *dst_pt =
 348                                 container_of(dst_pos, struct sync_pt, pt_list);
 349                         /* collapse two sync_pts on the same timeline
 350                          * to a single sync_pt that will signal at
 351                          * the later of the two
 352                          */
 353                         if (dst_pt->parent == src_pt->parent) {
 354                                 if (dst_pt->parent->ops->compare(dst_pt, src_pt)
 355                                                  == -1) {
 356                                         struct sync_pt *new_pt =
 357                                                 sync_pt_dup(src_pt);
 358                                         if (new_pt == NULL)
 359                                                 return -ENOMEM;
 360
 361                                         new_pt->fence = dst;
 362                                         list_replace(&dst_pt->pt_list,
 363                                                      &new_pt->pt_list);
 364                                         sync_pt_free(dst_pt);
 365                                 }
 366                                 collapsed = true;
 367                                 break;
 368                         }
 369                 }
 370
 371                 if (!collapsed) {
 372                         struct sync_pt *new_pt = sync_pt_dup(src_pt);
 373
 374                         if (new_pt == NULL)
 375                                 return -ENOMEM;
 376
 377                         new_pt->fence = dst;
 378                         list_add(&new_pt->pt_list, &dst->pt_list_head);
 379                 }
 380         }
 381
 382         return 0;
 383 }
 384
 385 static void sync_fence_detach_pts(struct sync_fence *fence)
 386 {
 387         struct list_head *pos, *n;
 388
 389         list_for_each_safe(pos, n, &fence->pt_list_head) {
 390                 struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list);
 391
 392                 sync_timeline_remove_pt(pt);
 393         }
 394 }
 395
 396 static void sync_fence_free_pts(struct sync_fence *fence)
 397 {
 398         struct list_head *pos, *n;
 399
 400         list_for_each_safe(pos, n, &fence->pt_list_head) {
 401                 struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list);
 402
 403                 sync_pt_free(pt);
 404         }
 405 }
 406
 407 struct sync_fence *sync_fence_fdget(int fd)
 408 {
 409         struct file *file = fget(fd);
 410
 411         if (file == NULL)
 412                 return NULL;
 413
 414         if (file->f_op != &sync_fence_fops)
 415                 goto err;
 416
 417         return file->private_data;
 418
 419 err:
 420         fput(file);
 421         return NULL;
 422 }
 423 EXPORT_SYMBOL(sync_fence_fdget);
 424
 425 void sync_fence_put(struct sync_fence *fence)
 426 {
 427         fput(fence->file);
 428 }
 429 EXPORT_SYMBOL(sync_fence_put);
 430
 431 void sync_fence_install(struct sync_fence *fence, int fd)
 432 {
 433         fd_install(fd, fence->file);
 434 }
 435 EXPORT_SYMBOL(sync_fence_install);
 436
 437 static int sync_fence_get_status(struct sync_fence *fence)
 438 {
 439         struct list_head *pos;
 440         int status = 1;
 441
 442         list_for_each(pos, &fence->pt_list_head) {
 443                 struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list);
 444                 int pt_status = pt->status;
 445
 446                 if (pt_status < 0) {
 447                         status = pt_status;
 448                         break;
 449                 } else if (status == 1) {
 450                         status = pt_status;
 451                 }
 452         }
 453
 454         return status;
 455 }
 456
 457 struct sync_fence *sync_fence_merge(const char *name,
 458                                     struct sync_fence *a, struct sync_fence *b)
 459 {
 460         struct sync_fence *fence;
 461         struct list_head *pos;
 462         int err;
 463
 464         fence = sync_fence_alloc(name);
 465         if (fence == NULL)
 466                 return NULL;
 467
 468         err = sync_fence_copy_pts(fence, a);
 469         if (err < 0)
 470                 goto err;
 471
 472         err = sync_fence_merge_pts(fence, b);
 473         if (err < 0)
 474                 goto err;
 475
 476         list_for_each(pos, &fence->pt_list_head) {
 477                 struct sync_pt *pt =
 478                         container_of(pos, struct sync_pt, pt_list);
 479                 sync_pt_activate(pt);
 480         }
 481
 482         /*
 483          * signal the fence in case one of it's pts were activated before
 484          * they were activated
 485          */
 486         sync_fence_signal_pt(list_first_entry(&fence->pt_list_head,
 487                                               struct sync_pt,
 488                                               pt_list));
 489
 490         return fence;
 491 err:
 492         sync_fence_free_pts(fence);
 493         kfree(fence);
 494         return NULL;
 495 }
 496 EXPORT_SYMBOL(sync_fence_merge);
 497
 498 static void sync_fence_signal_pt(struct sync_pt *pt)
 499 {
 500         LIST_HEAD(signaled_waiters);
 501         struct sync_fence *fence = pt->fence;
 502         struct list_head *pos;
 503         struct list_head *n;
 504         unsigned long flags;
 505         int status;
 506
 507         status = sync_fence_get_status(fence);
 508
 509         spin_lock_irqsave(&fence->waiter_list_lock, flags);
 510         /*
 511          * this should protect against two threads racing on the signaled
 512          * false -> true transition
 513          */
 514         if (status && !fence->status) {
 515                 list_for_each_safe(pos, n, &fence->waiter_list_head)
 516                         list_move(pos, &signaled_waiters);
 517
 518                 fence->status = status;
 519         } else {
 520                 status = 0;
 521         }
 522         spin_unlock_irqrestore(&fence->waiter_list_lock, flags);
 523
 524         if (status) {
 525                 list_for_each_safe(pos, n, &signaled_waiters) {
 526                         struct sync_fence_waiter *waiter =
 527                                 container_of(pos, struct sync_fence_waiter,
 528                                              waiter_list);
 529
 530                         list_del(pos);
 531                         waiter->callback(fence, waiter);
 532                 }
 533                 wake_up(&fence->wq);
 534         }
 535 }
 536
 537 int sync_fence_wait_async(struct sync_fence *fence,
 538                           struct sync_fence_waiter *waiter)
 539 {
 540         unsigned long flags;
 541         int err = 0;
 542
 543         spin_lock_irqsave(&fence->waiter_list_lock, flags);
 544
 545         if (fence->status) {
 546                 err = fence->status;
 547                 goto out;
 548         }
 549
 550         list_add_tail(&waiter->waiter_list, &fence->waiter_list_head);
 551 out:
 552         spin_unlock_irqrestore(&fence->waiter_list_lock, flags);
 553
 554         return err;
 555 }
 556 EXPORT_SYMBOL(sync_fence_wait_async);
 557
 558 int sync_fence_cancel_async(struct sync_fence *fence,
 559                              struct sync_fence_waiter *waiter)
 560 {
 561         struct list_head *pos;
 562         struct list_head *n;
 563         unsigned long flags;
 564         int ret = -ENOENT;
 565
 566         spin_lock_irqsave(&fence->waiter_list_lock, flags);
 567         /*
 568          * Make sure waiter is still in waiter_list because it is possible for
 569          * the waiter to be removed from the list while the callback is still
 570          * pending.
 571          */
 572         list_for_each_safe(pos, n, &fence->waiter_list_head) {
 573                 struct sync_fence_waiter *list_waiter =
 574                         container_of(pos, struct sync_fence_waiter,
 575                                      waiter_list);
 576                 if (list_waiter == waiter) {
 577                         list_del(pos);
 578                         ret = 0;
 579                         break;
 580                 }
 581         }
 582         spin_unlock_irqrestore(&fence->waiter_list_lock, flags);
 583         return ret;
 584 }
 585 EXPORT_SYMBOL(sync_fence_cancel_async);
 586
 587 static bool sync_fence_check(struct sync_fence *fence)
 588 {
 589         /*
 590          * Make sure that reads to fence->status are ordered with the
 591          * wait queue event triggering
 592          */
 593         smp_rmb();
 594         return fence->status != 0;
 595 }
 596
 597 int sync_fence_wait(struct sync_fence *fence, long timeout)
 598 {
 599         int err = 0;
 600         struct sync_pt *pt;
 601
 602         trace_sync_wait(fence, 1);
 603         list_for_each_entry(pt, &fence->pt_list_head, pt_list)
 604                 trace_sync_pt(pt);
 605
 606         if (timeout > 0) {
 607                 timeout = msecs_to_jiffies(timeout);
 608                 err = wait_event_interruptible_timeout(fence->wq,
 609                                                        sync_fence_check(fence),
 610                                                        timeout);
 611         } else if (timeout < 0) {
 612                 err = wait_event_interruptible(fence->wq,
 613                                                sync_fence_check(fence));
 614         }
 615         trace_sync_wait(fence, 0);
 616
 617         if (err < 0)
 618                 return err;
 619
 620         if (fence->status < 0) {
 621                 pr_info("fence error %d on [%p]\n", fence->status, fence);
 622                 sync_dump();
 623                 return fence->status;
 624         }
 625
 626         if (fence->status == 0) {
 627                 if (timeout > 0) {
 628                         pr_info("fence timeout on [%p] after %dms\n", fence,
 629                                 jiffies_to_msecs(timeout));
 630                         sync_dump();
 631                 }
 632                 return -ETIME;
 633         }
 634
 635         return 0;
 636 }
 637 EXPORT_SYMBOL(sync_fence_wait);
 638
 639 static void sync_fence_free(struct kref *kref)
 640 {
 641         struct sync_fence *fence = container_of(kref, struct sync_fence, kref);
 642
 643         sync_fence_free_pts(fence);
 644
 645         kfree(fence);
 646 }
 647
 648 static int sync_fence_release(struct inode *inode, struct file *file)
 649 {
 650         struct sync_fence *fence = file->private_data;
 651         unsigned long flags;
 652
 653         /*
 654          * We need to remove all ways to access this fence before droping
 655          * our ref.
 656          *
 657          * start with its membership in the global fence list
 658          */
 659         spin_lock_irqsave(&sync_fence_list_lock, flags);
 660         list_del(&fence->sync_fence_list);
 661         spin_unlock_irqrestore(&sync_fence_list_lock, flags);
 662
 663         /*
 664          * remove its pts from their parents so that sync_timeline_signal()
 665          * can't reference the fence.
 666          */
 667         sync_fence_detach_pts(fence);
 668
 669         kref_put(&fence->kref, sync_fence_free);
 670
 671         return 0;
 672 }
 673
 674 static unsigned int sync_fence_poll(struct file *file, poll_table *wait)
 675 {
 676         struct sync_fence *fence = file->private_data;
 677
 678         poll_wait(file, &fence->wq, wait);
 679
 680         /*
 681          * Make sure that reads to fence->status are ordered with the
 682          * wait queue event triggering
 683          */
 684         smp_rmb();
 685
 686         if (fence->status == 1)
 687                 return POLLIN;
 688         else if (fence->status < 0)
 689                 return POLLERR;
 690         else
 691                 return 0;
 692 }
 693
 694 static long sync_fence_ioctl_wait(struct sync_fence *fence, unsigned long arg)
 695 {
 696         __s32 value;
 697
 698         if (copy_from_user(&value, (void __user *)arg, sizeof(value)))
 699                 return -EFAULT;
 700
 701         return sync_fence_wait(fence, value);
 702 }
 703
 704 static long sync_fence_ioctl_merge(struct sync_fence *fence, unsigned long arg)
 705 {
 706         int fd = get_unused_fd_flags(O_CLOEXEC);
 707         int err;
 708         struct sync_fence *fence2, *fence3;
 709         struct sync_merge_data data;
 710
 711         if (fd < 0)
 712                 return fd;
 713
 714         if (copy_from_user(&data, (void __user *)arg, sizeof(data))) {
 715                 err = -EFAULT;
 716                 goto err_put_fd;
 717         }
 718
 719         fence2 = sync_fence_fdget(data.fd2);
 720         if (fence2 == NULL) {
 721                 err = -ENOENT;
 722                 goto err_put_fd;
 723         }
 724
 725         data.name[sizeof(data.name) - 1] = '\0';
 726         fence3 = sync_fence_merge(data.name, fence, fence2);
 727         if (fence3 == NULL) {
 728                 err = -ENOMEM;
 729                 goto err_put_fence2;
 730         }
 731
 732         data.fence = fd;
 733         if (copy_to_user((void __user *)arg, &data, sizeof(data))) {
 734                 err = -EFAULT;
 735                 goto err_put_fence3;
 736         }
 737
 738         sync_fence_install(fence3, fd);
 739         sync_fence_put(fence2);
 740         return 0;
 741
 742 err_put_fence3:
 743         sync_fence_put(fence3);
 744
 745 err_put_fence2:
 746         sync_fence_put(fence2);
 747
 748 err_put_fd:
 749         put_unused_fd(fd);
 750         return err;
 751 }
 752
 753 static int sync_fill_pt_info(struct sync_pt *pt, void *data, int size)
 754 {
 755         struct sync_pt_info *info = data;
 756         int ret;
 757
 758         if (size < sizeof(struct sync_pt_info))
 759                 return -ENOMEM;
 760
 761         info->len = sizeof(struct sync_pt_info);
 762
 763         if (pt->parent->ops->fill_driver_data) {
 764                 ret = pt->parent->ops->fill_driver_data(pt, info->driver_data,
 765                                                         size - sizeof(*info));
 766                 if (ret < 0)
 767                         return ret;
 768
 769                 info->len += ret;
 770         }
 771
 772         strlcpy(info->obj_name, pt->parent->name, sizeof(info->obj_name));
 773         strlcpy(info->driver_name, pt->parent->ops->driver_name,
 774                 sizeof(info->driver_name));
 775         info->status = pt->status;
 776         info->timestamp_ns = ktime_to_ns(pt->timestamp);
 777
 778         return info->len;
 779 }
 780
 781 static long sync_fence_ioctl_fence_info(struct sync_fence *fence,
 782                                         unsigned long arg)
 783 {
 784         struct sync_fence_info_data *data;
 785         struct list_head *pos;
 786         __u32 size;
 787         __u32 len = 0;
 788         int ret;
 789
 790         if (copy_from_user(&size, (void __user *)arg, sizeof(size)))
 791                 return -EFAULT;
 792
 793         if (size < sizeof(struct sync_fence_info_data))
 794                 return -EINVAL;
 795
 796         if (size > 4096)
 797                 size = 4096;
 798
 799         data = kzalloc(size, GFP_KERNEL);
 800         if (data == NULL)
 801                 return -ENOMEM;
 802
 803         strlcpy(data->name, fence->name, sizeof(data->name));
 804         data->status = fence->status;
 805         len = sizeof(struct sync_fence_info_data);
 806
 807         list_for_each(pos, &fence->pt_list_head) {
 808                 struct sync_pt *pt =
 809                         container_of(pos, struct sync_pt, pt_list);
 810
 811                 ret = sync_fill_pt_info(pt, (u8 *)data + len, size - len);
 812
 813                 if (ret < 0)
 814                         goto out;
 815
 816                 len += ret;
 817         }
 818
 819         data->len = len;
 820
 821         if (copy_to_user((void __user *)arg, data, len))
 822                 ret = -EFAULT;
 823         else
 824                 ret = 0;
 825
 826 out:
 827         kfree(data);
 828
 829         return ret;
 830 }
 831
 832 static long sync_fence_ioctl(struct file *file, unsigned int cmd,
 833                              unsigned long arg)
 834 {
 835         struct sync_fence *fence = file->private_data;
 836
 837         switch (cmd) {
 838         case SYNC_IOC_WAIT:
 839                 return sync_fence_ioctl_wait(fence, arg);
 840
 841         case SYNC_IOC_MERGE:
 842                 return sync_fence_ioctl_merge(fence, arg);
 843
 844         case SYNC_IOC_FENCE_INFO:
 845                 return sync_fence_ioctl_fence_info(fence, arg);
 846
 847         default:
 848                 return -ENOTTY;
 849         }
 850 }
 851
 852 #ifdef CONFIG_DEBUG_FS
 853 static const char *sync_status_str(int status)
 854 {
 855         if (status > 0)
 856                 return "signaled";
 857         else if (status == 0)
 858                 return "active";
 859         else
 860                 return "error";
 861 }
 862
 863 static void sync_print_pt(struct seq_file *s, struct sync_pt *pt, bool fence)
 864 {
 865         int status = pt->status;
 866
 867         seq_printf(s, "  %s%spt %s",
 868                    fence ? pt->parent->name : "",
 869                    fence ? "_" : "",
 870                    sync_status_str(status));
 871         if (pt->status) {
 872                 struct timeval tv = ktime_to_timeval(pt->timestamp);
 873
 874                 seq_printf(s, "@%ld.%06ld", tv.tv_sec, tv.tv_usec);
 875         }
 876
 877         if (pt->parent->ops->timeline_value_str &&
 878             pt->parent->ops->pt_value_str) {
 879                 char value[64];
 880
 881                 pt->parent->ops->pt_value_str(pt, value, sizeof(value));
 882                 seq_printf(s, ": %s", value);
 883                 if (fence) {
 884                         pt->parent->ops->timeline_value_str(pt->parent, value,
 885                                                     sizeof(value));
 886                         seq_printf(s, " / %s", value);
 887                 }
 888         } else if (pt->parent->ops->print_pt) {
 889                 seq_puts(s, ": ");
 890                 pt->parent->ops->print_pt(s, pt);
 891         }
 892
 893         seq_puts(s, "\n");
 894 }
 895
 896 static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
 897 {
 898         struct list_head *pos;
 899         unsigned long flags;
 900
 901         seq_printf(s, "%s %s", obj->name, obj->ops->driver_name);
 902
 903         if (obj->ops->timeline_value_str) {
 904                 char value[64];
 905
 906                 obj->ops->timeline_value_str(obj, value, sizeof(value));
 907                 seq_printf(s, ": %s", value);
 908         } else if (obj->ops->print_obj) {
 909                 seq_puts(s, ": ");
 910                 obj->ops->print_obj(s, obj);
 911         }
 912
 913         seq_puts(s, "\n");
 914
 915         spin_lock_irqsave(&obj->child_list_lock, flags);
 916         list_for_each(pos, &obj->child_list_head) {
 917                 struct sync_pt *pt =
 918                         container_of(pos, struct sync_pt, child_list);
 919                 sync_print_pt(s, pt, false);
 920         }
 921         spin_unlock_irqrestore(&obj->child_list_lock, flags);
 922 }
 923
 924 static void sync_print_fence(struct seq_file *s, struct sync_fence *fence)
 925 {
 926         struct list_head *pos;
 927         unsigned long flags;
 928
 929         seq_printf(s, "[%p] %s: %s\n", fence, fence->name,
 930                    sync_status_str(fence->status));
 931
 932         list_for_each(pos, &fence->pt_list_head) {
 933                 struct sync_pt *pt =
 934                         container_of(pos, struct sync_pt, pt_list);
 935                 sync_print_pt(s, pt, true);
 936         }
 937
 938         spin_lock_irqsave(&fence->waiter_list_lock, flags);
 939         list_for_each(pos, &fence->waiter_list_head) {
 940                 struct sync_fence_waiter *waiter =
 941                         container_of(pos, struct sync_fence_waiter,
 942                                      waiter_list);
 943
 944                 seq_printf(s, "waiter %pF\n", waiter->callback);
 945         }
 946         spin_unlock_irqrestore(&fence->waiter_list_lock, flags);
 947 }
 948
 949 static int sync_debugfs_show(struct seq_file *s, void *unused)
 950 {
 951         unsigned long flags;
 952         struct list_head *pos;
 953
 954         seq_puts(s, "objs:\n--------------\n");
 955
 956         spin_lock_irqsave(&sync_timeline_list_lock, flags);
 957         list_for_each(pos, &sync_timeline_list_head) {
 958                 struct sync_timeline *obj =
 959                         container_of(pos, struct sync_timeline,
 960                                      sync_timeline_list);
 961
 962                 sync_print_obj(s, obj);
 963                 seq_puts(s, "\n");
 964         }
 965         spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
 966
 967         seq_puts(s, "fences:\n--------------\n");
 968
 969         spin_lock_irqsave(&sync_fence_list_lock, flags);
 970         list_for_each(pos, &sync_fence_list_head) {
 971                 struct sync_fence *fence =
 972                         container_of(pos, struct sync_fence, sync_fence_list);
 973
 974                 sync_print_fence(s, fence);
 975                 seq_puts(s, "\n");
 976         }
 977         spin_unlock_irqrestore(&sync_fence_list_lock, flags);
 978         return 0;
 979 }
 980
 981 static int sync_debugfs_open(struct inode *inode, struct file *file)
 982 {
 983         return single_open(file, sync_debugfs_show, inode->i_private);
 984 }
 985
 986 static const struct file_operations sync_debugfs_fops = {
 987         .open           = sync_debugfs_open,
 988         .read           = seq_read,
 989         .llseek         = seq_lseek,
 990         .release        = single_release,
 991 };
 992
 993 static __init int sync_debugfs_init(void)
 994 {
 995         debugfs_create_file("sync", S_IRUGO, NULL, NULL, &sync_debugfs_fops);
 996         return 0;
 997 }
 998 late_initcall(sync_debugfs_init);
 999
1000 #define DUMP_CHUNK 256
1001 static char sync_dump_buf[64 * 1024];
1002 static void sync_dump(void)
1003 {
1004         struct seq_file s = {
1005                 .buf = sync_dump_buf,
1006                 .size = sizeof(sync_dump_buf) - 1,
1007         };
1008         int i;
1009
1010         sync_debugfs_show(&s, NULL);
1011
1012         for (i = 0; i < s.count; i += DUMP_CHUNK) {
1013                 if ((s.count - i) > DUMP_CHUNK) {
1014                         char c = s.buf[i + DUMP_CHUNK];
1015
1016                         s.buf[i + DUMP_CHUNK] = 0;
1017                         pr_cont("%s", s.buf + i);
1018                         s.buf[i + DUMP_CHUNK] = c;
1019                 } else {
1020                         s.buf[s.count] = 0;
1021                         pr_cont("%s", s.buf + i);
1022                 }
1023         }
1024 }
1025 #else
1026 static void sync_dump(void)
1027 {
1028 }
1029 #endif