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