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, see struct &drm_syncobj) provide a
  33  * container for a synchronization primitive which can be used by userspace
  34  * to explicitly synchronize GPU commands, can be shared between userspace
  35  * processes, and can be shared between different DRM drivers.
  36  * Their primary use-case is to implement Vulkan fences and semaphores.
  37  * The syncobj userspace API provides ioctls for several operations:
  38  *
  39  *  - Creation and destruction of syncobjs
  40  *  - Import and export of syncobjs to/from a syncobj file descriptor
  41  *  - Import and export a syncobj's underlying fence to/from a sync file
  42  *  - Reset a syncobj (set its fence to NULL)
  43  *  - Signal a syncobj (set a trivially signaled fence)
  44  *  - Wait for a syncobj's fence to appear and be signaled
  45  *
  46  * The syncobj userspace API also provides operations to manipulate a syncobj
  47  * in terms of a timeline of struct &dma_fence_chain rather than a single
  48  * struct &dma_fence, through the following operations:
  49  *
  50  *   - Signal a given point on the timeline
  51  *   - Wait for a given point to appear and/or be signaled
  52  *   - Import and export from/to a given point of a timeline
  53  *
  54  * At it's core, a syncobj is simply a wrapper around a pointer to a struct
  55  * &dma_fence which may be NULL.
  56  * When a syncobj is first created, its pointer is either NULL or a pointer
  57  * to an already signaled fence depending on whether the
  58  * &DRM_SYNCOBJ_CREATE_SIGNALED flag is passed to
  59  * &DRM_IOCTL_SYNCOBJ_CREATE.
  60  *
  61  * If the syncobj is considered as a binary (its state is either signaled or
  62  * unsignaled) primitive, when GPU work is enqueued in a DRM driver to signal
  63  * the syncobj, the syncobj's fence is replaced with a fence which will be
  64  * signaled by the completion of that work.
  65  * If the syncobj is considered as a timeline primitive, when GPU work is
  66  * enqueued in a DRM driver to signal the a given point of the syncobj, a new
  67  * struct &dma_fence_chain pointing to the DRM driver's fence and also
  68  * pointing to the previous fence that was in the syncobj. The new struct
  69  * &dma_fence_chain fence replace the syncobj's fence and will be signaled by
  70  * completion of the DRM driver's work and also any work associated with the
  71  * fence previously in the syncobj.
  72  *
  73  * When GPU work which waits on a syncobj is enqueued in a DRM driver, at the
  74  * time the work is enqueued, it waits on the syncobj's fence before
  75  * submitting the work to hardware. That fence is either :
  76  *
  77  *    - The syncobj's current fence if the syncobj is considered as a binary
  78  *      primitive.
  79  *    - The struct &dma_fence associated with a given point if the syncobj is
  80  *      considered as a timeline primitive.
  81  *
  82  * If the syncobj's fence is NULL or not present in the syncobj's timeline,
  83  * the enqueue operation is expected to fail.
  84  *
  85  * With binary syncobj, all manipulation of the syncobjs's fence happens in
  86  * terms of the current fence at the time the ioctl is called by userspace
  87  * regardless of whether that operation is an immediate host-side operation
  88  * (signal or reset) or or an operation which is enqueued in some driver
  89  * queue. &DRM_IOCTL_SYNCOBJ_RESET and &DRM_IOCTL_SYNCOBJ_SIGNAL can be used
  90  * to manipulate a syncobj from the host by resetting its pointer to NULL or
  91  * setting its pointer to a fence which is already signaled.
  92  *
  93  * With a timeline syncobj, all manipulation of the synobj's fence happens in
  94  * terms of a u64 value referring to point in the timeline. See
  95  * dma_fence_chain_find_seqno() to see how a given point is found in the
  96  * timeline.
  97  *
  98  * Note that applications should be careful to always use timeline set of
  99  * ioctl() when dealing with syncobj considered as timeline. Using a binary
 100  * set of ioctl() with a syncobj considered as timeline could result incorrect
 101  * synchronization. The use of binary syncobj is supported through the
 102  * timeline set of ioctl() by using a point value of 0, this will reproduce
 103  * the behavior of the binary set of ioctl() (for example replace the
 104  * syncobj's fence when signaling).
 105  *
 106  *
 107  * Host-side wait on syncobjs
 108  * --------------------------
 109  *
 110  * &DRM_IOCTL_SYNCOBJ_WAIT takes an array of syncobj handles and does a
 111  * host-side wait on all of the syncobj fences simultaneously.
 112  * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL is set, the wait ioctl will wait on
 113  * all of the syncobj fences to be signaled before it returns.
 114  * Otherwise, it returns once at least one syncobj fence has been signaled
 115  * and the index of a signaled fence is written back to the client.
 116  *
 117  * Unlike the enqueued GPU work dependencies which fail if they see a NULL
 118  * fence in a syncobj, if &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is set,
 119  * the host-side wait will first wait for the syncobj to receive a non-NULL
 120  * fence and then wait on that fence.
 121  * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT is not set and any one of the
 122  * syncobjs in the array has a NULL fence, -EINVAL will be returned.
 123  * Assuming the syncobj starts off with a NULL fence, this allows a client
 124  * to do a host wait in one thread (or process) which waits on GPU work
 125  * submitted in another thread (or process) without having to manually
 126  * synchronize between the two.
 127  * This requirement is inherited from the Vulkan fence API.
 128  *
 129  * If &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE is set, the ioctl will also set
 130  * a fence deadline hint on the backing fences before waiting, to provide the
 131  * fence signaler with an appropriate sense of urgency.  The deadline is
 132  * specified as an absolute &CLOCK_MONOTONIC value in units of ns.
 133  *
 134  * Similarly, &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT takes an array of syncobj
 135  * handles as well as an array of u64 points and does a host-side wait on all
 136  * of syncobj fences at the given points simultaneously.
 137  *
 138  * &DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT also adds the ability to wait for a given
 139  * fence to materialize on the timeline without waiting for the fence to be
 140  * signaled by using the &DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE flag. This
 141  * requirement is inherited from the wait-before-signal behavior required by
 142  * the Vulkan timeline semaphore API.
 143  *
 144  * Alternatively, &DRM_IOCTL_SYNCOBJ_EVENTFD can be used to wait without
 145  * blocking: an eventfd will be signaled when the syncobj is. This is useful to
 146  * integrate the wait in an event loop.
 147  *
 148  *
 149  * Import/export of syncobjs
 150  * -------------------------
 151  *
 152  * &DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE and &DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD
 153  * provide two mechanisms for import/export of syncobjs.
 154  *
 155  * The first lets the client import or export an entire syncobj to a file
 156  * descriptor.
 157  * These fd's are opaque and have no other use case, except passing the
 158  * syncobj between processes.
 159  * All exported file descriptors and any syncobj handles created as a
 160  * result of importing those file descriptors own a reference to the
 161  * same underlying struct &drm_syncobj and the syncobj can be used
 162  * persistently across all the processes with which it is shared.
 163  * The syncobj is freed only once the last reference is dropped.
 164  * Unlike dma-buf, importing a syncobj creates a new handle (with its own
 165  * reference) for every import instead of de-duplicating.
 166  * The primary use-case of this persistent import/export is for shared
 167  * Vulkan fences and semaphores.
 168  *
 169  * The second import/export mechanism, which is indicated by
 170  * &DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE or
 171  * &DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE lets the client
 172  * import/export the syncobj's current fence from/to a &sync_file.
 173  * When a syncobj is exported to a sync file, that sync file wraps the
 174  * sycnobj's fence at the time of export and any later signal or reset
 175  * operations on the syncobj will not affect the exported sync file.
 176  * When a sync file is imported into a syncobj, the syncobj's fence is set
 177  * to the fence wrapped by that sync file.
 178  * Because sync files are immutable, resetting or signaling the syncobj
 179  * will not affect any sync files whose fences have been imported into the
 180  * syncobj.
 181  *
 182  *
 183  * Import/export of timeline points in timeline syncobjs
 184  * -----------------------------------------------------
 185  *
 186  * &DRM_IOCTL_SYNCOBJ_TRANSFER provides a mechanism to transfer a struct
 187  * &dma_fence_chain of a syncobj at a given u64 point to another u64 point
 188  * into another syncobj.
 189  *
 190  * Note that if you want to transfer a struct &dma_fence_chain from a given
 191  * point on a timeline syncobj from/into a binary syncobj, you can use the
 192  * point 0 to mean take/replace the fence in the syncobj.
 193  */
 194
 195 #include <linux/anon_inodes.h>
 196 #include <linux/dma-fence-unwrap.h>
 197 #include <linux/eventfd.h>
 198 #include <linux/file.h>
 199 #include <linux/fs.h>
 200 #include <linux/sched/signal.h>
 201 #include <linux/sync_file.h>
 202 #include <linux/uaccess.h>
 203
 204 #include <drm/drm.h>
 205 #include <drm/drm_drv.h>
 206 #include <drm/drm_file.h>
 207 #include <drm/drm_gem.h>
 208 #include <drm/drm_print.h>
 209 #include <drm/drm_syncobj.h>
 210 #include <drm/drm_utils.h>
 211
 212 #include "drm_internal.h"
 213
 214 struct syncobj_wait_entry {
 215         struct list_head node;
 216         struct task_struct *task;
 217         struct dma_fence *fence;
 218         struct dma_fence_cb fence_cb;
 219         u64    point;
 220 };
 221
 222 static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
 223                                       struct syncobj_wait_entry *wait);
 224
 225 struct syncobj_eventfd_entry {
 226         struct list_head node;
 227         struct dma_fence *fence;
 228         struct dma_fence_cb fence_cb;
 229         struct drm_syncobj *syncobj;
 230         struct eventfd_ctx *ev_fd_ctx;
 231         u64 point;
 232         u32 flags;
 233 };
 234
 235 static void
 236 syncobj_eventfd_entry_func(struct drm_syncobj *syncobj,
 237                            struct syncobj_eventfd_entry *entry);
 238
 239 /**
 240  * drm_syncobj_find - lookup and reference a sync object.
 241  * @file_private: drm file private pointer
 242  * @handle: sync object handle to lookup.
 243  *
 244  * Returns a reference to the syncobj pointed to by handle or NULL. The
 245  * reference must be released by calling drm_syncobj_put().
 246  */
 247 struct drm_syncobj *drm_syncobj_find(struct drm_file *file_private,
 248                                      u32 handle)
 249 {
 250         struct drm_syncobj *syncobj;
 251
 252         spin_lock(&file_private->syncobj_table_lock);
 253
 254         /* Check if we currently have a reference on the object */
 255         syncobj = idr_find(&file_private->syncobj_idr, handle);
 256         if (syncobj)
 257                 drm_syncobj_get(syncobj);
 258
 259         spin_unlock(&file_private->syncobj_table_lock);
 260
 261         return syncobj;
 262 }
 263 EXPORT_SYMBOL(drm_syncobj_find);
 264
 265 static void drm_syncobj_fence_add_wait(struct drm_syncobj *syncobj,
 266                                        struct syncobj_wait_entry *wait)
 267 {
 268         struct dma_fence *fence;
 269
 270         if (wait->fence)
 271                 return;
 272
 273         spin_lock(&syncobj->lock);
 274         /* We've already tried once to get a fence and failed.  Now that we
 275          * have the lock, try one more time just to be sure we don't add a
 276          * callback when a fence has already been set.
 277          */
 278         fence = dma_fence_get(rcu_dereference_protected(syncobj->fence, 1));
 279         if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
 280                 dma_fence_put(fence);
 281                 list_add_tail(&wait->node, &syncobj->cb_list);
 282         } else if (!fence) {
 283                 wait->fence = dma_fence_get_stub();
 284         } else {
 285                 wait->fence = fence;
 286         }
 287         spin_unlock(&syncobj->lock);
 288 }
 289
 290 static void drm_syncobj_remove_wait(struct drm_syncobj *syncobj,
 291                                     struct syncobj_wait_entry *wait)
 292 {
 293         if (!wait->node.next)
 294                 return;
 295
 296         spin_lock(&syncobj->lock);
 297         list_del_init(&wait->node);
 298         spin_unlock(&syncobj->lock);
 299 }
 300
 301 static void
 302 syncobj_eventfd_entry_free(struct syncobj_eventfd_entry *entry)
 303 {
 304         eventfd_ctx_put(entry->ev_fd_ctx);
 305         dma_fence_put(entry->fence);
 306         /* This happens either inside the syncobj lock, or after the node has
 307          * already been removed from the list.
 308          */
 309         list_del(&entry->node);
 310         kfree(entry);
 311 }
 312
 313 static void
 314 drm_syncobj_add_eventfd(struct drm_syncobj *syncobj,
 315                         struct syncobj_eventfd_entry *entry)
 316 {
 317         spin_lock(&syncobj->lock);
 318         list_add_tail(&entry->node, &syncobj->ev_fd_list);
 319         syncobj_eventfd_entry_func(syncobj, entry);
 320         spin_unlock(&syncobj->lock);
 321 }
 322
 323 /**
 324  * drm_syncobj_add_point - add new timeline point to the syncobj
 325  * @syncobj: sync object to add timeline point do
 326  * @chain: chain node to use to add the point
 327  * @fence: fence to encapsulate in the chain node
 328  * @point: sequence number to use for the point
 329  *
 330  * Add the chain node as new timeline point to the syncobj.
 331  */
 332 void drm_syncobj_add_point(struct drm_syncobj *syncobj,
 333                            struct dma_fence_chain *chain,
 334                            struct dma_fence *fence,
 335                            uint64_t point)
 336 {
 337         struct syncobj_wait_entry *wait_cur, *wait_tmp;
 338         struct syncobj_eventfd_entry *ev_fd_cur, *ev_fd_tmp;
 339         struct dma_fence *prev;
 340
 341         dma_fence_get(fence);
 342
 343         spin_lock(&syncobj->lock);
 344
 345         prev = drm_syncobj_fence_get(syncobj);
 346         /* You are adding an unorder point to timeline, which could cause payload returned from query_ioctl is 0! */
 347         if (prev && prev->seqno >= point)
 348                 DRM_DEBUG("You are adding an unorder point to timeline!\n");
 349         dma_fence_chain_init(chain, prev, fence, point);
 350         rcu_assign_pointer(syncobj->fence, &chain->base);
 351
 352         list_for_each_entry_safe(wait_cur, wait_tmp, &syncobj->cb_list, node)
 353                 syncobj_wait_syncobj_func(syncobj, wait_cur);
 354         list_for_each_entry_safe(ev_fd_cur, ev_fd_tmp, &syncobj->ev_fd_list, node)
 355                 syncobj_eventfd_entry_func(syncobj, ev_fd_cur);
 356         spin_unlock(&syncobj->lock);
 357
 358         /* Walk the chain once to trigger garbage collection */
 359         dma_fence_chain_for_each(fence, prev);
 360         dma_fence_put(prev);
 361 }
 362 EXPORT_SYMBOL(drm_syncobj_add_point);
 363
 364 /**
 365  * drm_syncobj_replace_fence - replace fence in a sync object.
 366  * @syncobj: Sync object to replace fence in
 367  * @fence: fence to install in sync file.
 368  *
 369  * This replaces the fence on a sync object.
 370  */
 371 void drm_syncobj_replace_fence(struct drm_syncobj *syncobj,
 372                                struct dma_fence *fence)
 373 {
 374         struct dma_fence *old_fence;
 375         struct syncobj_wait_entry *wait_cur, *wait_tmp;
 376         struct syncobj_eventfd_entry *ev_fd_cur, *ev_fd_tmp;
 377
 378         if (fence)
 379                 dma_fence_get(fence);
 380
 381         spin_lock(&syncobj->lock);
 382
 383         old_fence = rcu_dereference_protected(syncobj->fence,
 384                                               lockdep_is_held(&syncobj->lock));
 385         rcu_assign_pointer(syncobj->fence, fence);
 386
 387         if (fence != old_fence) {
 388                 list_for_each_entry_safe(wait_cur, wait_tmp, &syncobj->cb_list, node)
 389                         syncobj_wait_syncobj_func(syncobj, wait_cur);
 390                 list_for_each_entry_safe(ev_fd_cur, ev_fd_tmp, &syncobj->ev_fd_list, node)
 391                         syncobj_eventfd_entry_func(syncobj, ev_fd_cur);
 392         }
 393
 394         spin_unlock(&syncobj->lock);
 395
 396         dma_fence_put(old_fence);
 397 }
 398 EXPORT_SYMBOL(drm_syncobj_replace_fence);
 399
 400 /**
 401  * drm_syncobj_assign_null_handle - assign a stub fence to the sync object
 402  * @syncobj: sync object to assign the fence on
 403  *
 404  * Assign a already signaled stub fence to the sync object.
 405  */
 406 static int drm_syncobj_assign_null_handle(struct drm_syncobj *syncobj)
 407 {
 408         struct dma_fence *fence = dma_fence_allocate_private_stub(ktime_get());
 409
 410         if (!fence)
 411                 return -ENOMEM;
 412
 413         drm_syncobj_replace_fence(syncobj, fence);
 414         dma_fence_put(fence);
 415         return 0;
 416 }
 417
 418 /* 5s default for wait submission */
 419 #define DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT 5000000000ULL
 420 /**
 421  * drm_syncobj_find_fence - lookup and reference the fence in a sync object
 422  * @file_private: drm file private pointer
 423  * @handle: sync object handle to lookup.
 424  * @point: timeline point
 425  * @flags: DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT or not
 426  * @fence: out parameter for the fence
 427  *
 428  * This is just a convenience function that combines drm_syncobj_find() and
 429  * drm_syncobj_fence_get().
 430  *
 431  * Returns 0 on success or a negative error value on failure. On success @fence
 432  * contains a reference to the fence, which must be released by calling
 433  * dma_fence_put().
 434  */
 435 int drm_syncobj_find_fence(struct drm_file *file_private,
 436                            u32 handle, u64 point, u64 flags,
 437                            struct dma_fence **fence)
 438 {
 439         struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
 440         struct syncobj_wait_entry wait;
 441         u64 timeout = nsecs_to_jiffies64(DRM_SYNCOBJ_WAIT_FOR_SUBMIT_TIMEOUT);
 442         int ret;
 443
 444         if (!syncobj)
 445                 return -ENOENT;
 446
 447         /* Waiting for userspace with locks help is illegal cause that can
 448          * trivial deadlock with page faults for example. Make lockdep complain
 449          * about it early on.
 450          */
 451         if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT) {
 452                 might_sleep();
 453                 lockdep_assert_none_held_once();
 454         }
 455
 456         *fence = drm_syncobj_fence_get(syncobj);
 457
 458         if (*fence) {
 459                 ret = dma_fence_chain_find_seqno(fence, point);
 460                 if (!ret) {
 461                         /* If the requested seqno is already signaled
 462                          * drm_syncobj_find_fence may return a NULL
 463                          * fence. To make sure the recipient gets
 464                          * signalled, use a new fence instead.
 465                          */
 466                         if (!*fence)
 467                                 *fence = dma_fence_get_stub();
 468
 469                         goto out;
 470                 }
 471                 dma_fence_put(*fence);
 472         } else {
 473                 ret = -EINVAL;
 474         }
 475
 476         if (!(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT))
 477                 goto out;
 478
 479         memset(&wait, 0, sizeof(wait));
 480         wait.task = current;
 481         wait.point = point;
 482         drm_syncobj_fence_add_wait(syncobj, &wait);
 483
 484         do {
 485                 set_current_state(TASK_INTERRUPTIBLE);
 486                 if (wait.fence) {
 487                         ret = 0;
 488                         break;
 489                 }
 490                 if (timeout == 0) {
 491                         ret = -ETIME;
 492                         break;
 493                 }
 494
 495                 if (signal_pending(current)) {
 496                         ret = -ERESTARTSYS;
 497                         break;
 498                 }
 499
 500                 timeout = schedule_timeout(timeout);
 501         } while (1);
 502
 503         __set_current_state(TASK_RUNNING);
 504         *fence = wait.fence;
 505
 506         if (wait.node.next)
 507                 drm_syncobj_remove_wait(syncobj, &wait);
 508
 509 out:
 510         drm_syncobj_put(syncobj);
 511
 512         return ret;
 513 }
 514 EXPORT_SYMBOL(drm_syncobj_find_fence);
 515
 516 /**
 517  * drm_syncobj_free - free a sync object.
 518  * @kref: kref to free.
 519  *
 520  * Only to be called from kref_put in drm_syncobj_put.
 521  */
 522 void drm_syncobj_free(struct kref *kref)
 523 {
 524         struct drm_syncobj *syncobj = container_of(kref,
 525                                                    struct drm_syncobj,
 526                                                    refcount);
 527         struct syncobj_eventfd_entry *ev_fd_cur, *ev_fd_tmp;
 528
 529         drm_syncobj_replace_fence(syncobj, NULL);
 530
 531         list_for_each_entry_safe(ev_fd_cur, ev_fd_tmp, &syncobj->ev_fd_list, node)
 532                 syncobj_eventfd_entry_free(ev_fd_cur);
 533
 534         kfree(syncobj);
 535 }
 536 EXPORT_SYMBOL(drm_syncobj_free);
 537
 538 /**
 539  * drm_syncobj_create - create a new syncobj
 540  * @out_syncobj: returned syncobj
 541  * @flags: DRM_SYNCOBJ_* flags
 542  * @fence: if non-NULL, the syncobj will represent this fence
 543  *
 544  * This is the first function to create a sync object. After creating, drivers
 545  * probably want to make it available to userspace, either through
 546  * drm_syncobj_get_handle() or drm_syncobj_get_fd().
 547  *
 548  * Returns 0 on success or a negative error value on failure.
 549  */
 550 int drm_syncobj_create(struct drm_syncobj **out_syncobj, uint32_t flags,
 551                        struct dma_fence *fence)
 552 {
 553         int ret;
 554         struct drm_syncobj *syncobj;
 555
 556         syncobj = kzalloc(sizeof(struct drm_syncobj), GFP_KERNEL);
 557         if (!syncobj)
 558                 return -ENOMEM;
 559
 560         kref_init(&syncobj->refcount);
 561         INIT_LIST_HEAD(&syncobj->cb_list);
 562         INIT_LIST_HEAD(&syncobj->ev_fd_list);
 563         spin_lock_init(&syncobj->lock);
 564
 565         if (flags & DRM_SYNCOBJ_CREATE_SIGNALED) {
 566                 ret = drm_syncobj_assign_null_handle(syncobj);
 567                 if (ret < 0) {
 568                         drm_syncobj_put(syncobj);
 569                         return ret;
 570                 }
 571         }
 572
 573         if (fence)
 574                 drm_syncobj_replace_fence(syncobj, fence);
 575
 576         *out_syncobj = syncobj;
 577         return 0;
 578 }
 579 EXPORT_SYMBOL(drm_syncobj_create);
 580
 581 /**
 582  * drm_syncobj_get_handle - get a handle from a syncobj
 583  * @file_private: drm file private pointer
 584  * @syncobj: Sync object to export
 585  * @handle: out parameter with the new handle
 586  *
 587  * Exports a sync object created with drm_syncobj_create() as a handle on
 588  * @file_private to userspace.
 589  *
 590  * Returns 0 on success or a negative error value on failure.
 591  */
 592 int drm_syncobj_get_handle(struct drm_file *file_private,
 593                            struct drm_syncobj *syncobj, u32 *handle)
 594 {
 595         int ret;
 596
 597         /* take a reference to put in the idr */
 598         drm_syncobj_get(syncobj);
 599
 600         idr_preload(GFP_KERNEL);
 601         spin_lock(&file_private->syncobj_table_lock);
 602         ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
 603         spin_unlock(&file_private->syncobj_table_lock);
 604
 605         idr_preload_end();
 606
 607         if (ret < 0) {
 608                 drm_syncobj_put(syncobj);
 609                 return ret;
 610         }
 611
 612         *handle = ret;
 613         return 0;
 614 }
 615 EXPORT_SYMBOL(drm_syncobj_get_handle);
 616
 617 static int drm_syncobj_create_as_handle(struct drm_file *file_private,
 618                                         u32 *handle, uint32_t flags)
 619 {
 620         int ret;
 621         struct drm_syncobj *syncobj;
 622
 623         ret = drm_syncobj_create(&syncobj, flags, NULL);
 624         if (ret)
 625                 return ret;
 626
 627         ret = drm_syncobj_get_handle(file_private, syncobj, handle);
 628         drm_syncobj_put(syncobj);
 629         return ret;
 630 }
 631
 632 static int drm_syncobj_destroy(struct drm_file *file_private,
 633                                u32 handle)
 634 {
 635         struct drm_syncobj *syncobj;
 636
 637         spin_lock(&file_private->syncobj_table_lock);
 638         syncobj = idr_remove(&file_private->syncobj_idr, handle);
 639         spin_unlock(&file_private->syncobj_table_lock);
 640
 641         if (!syncobj)
 642                 return -EINVAL;
 643
 644         drm_syncobj_put(syncobj);
 645         return 0;
 646 }
 647
 648 static int drm_syncobj_file_release(struct inode *inode, struct file *file)
 649 {
 650         struct drm_syncobj *syncobj = file->private_data;
 651
 652         drm_syncobj_put(syncobj);
 653         return 0;
 654 }
 655
 656 static const struct file_operations drm_syncobj_file_fops = {
 657         .release = drm_syncobj_file_release,
 658 };
 659
 660 /**
 661  * drm_syncobj_get_fd - get a file descriptor from a syncobj
 662  * @syncobj: Sync object to export
 663  * @p_fd: out parameter with the new file descriptor
 664  *
 665  * Exports a sync object created with drm_syncobj_create() as a file descriptor.
 666  *
 667  * Returns 0 on success or a negative error value on failure.
 668  */
 669 int drm_syncobj_get_fd(struct drm_syncobj *syncobj, int *p_fd)
 670 {
 671         struct file *file;
 672         int fd;
 673
 674         fd = get_unused_fd_flags(O_CLOEXEC);
 675         if (fd < 0)
 676                 return fd;
 677
 678         file = anon_inode_getfile("syncobj_file",
 679                                   &drm_syncobj_file_fops,
 680                                   syncobj, 0);
 681         if (IS_ERR(file)) {
 682                 put_unused_fd(fd);
 683                 return PTR_ERR(file);
 684         }
 685
 686         drm_syncobj_get(syncobj);
 687         fd_install(fd, file);
 688
 689         *p_fd = fd;
 690         return 0;
 691 }
 692 EXPORT_SYMBOL(drm_syncobj_get_fd);
 693
 694 static int drm_syncobj_handle_to_fd(struct drm_file *file_private,
 695                                     u32 handle, int *p_fd)
 696 {
 697         struct drm_syncobj *syncobj = drm_syncobj_find(file_private, handle);
 698         int ret;
 699
 700         if (!syncobj)
 701                 return -EINVAL;
 702
 703         ret = drm_syncobj_get_fd(syncobj, p_fd);
 704         drm_syncobj_put(syncobj);
 705         return ret;
 706 }
 707
 708 static int drm_syncobj_fd_to_handle(struct drm_file *file_private,
 709                                     int fd, u32 *handle)
 710 {
 711         struct drm_syncobj *syncobj;
 712         struct fd f = fdget(fd);
 713         int ret;
 714
 715         if (!f.file)
 716                 return -EINVAL;
 717
 718         if (f.file->f_op != &drm_syncobj_file_fops) {
 719                 fdput(f);
 720                 return -EINVAL;
 721         }
 722
 723         /* take a reference to put in the idr */
 724         syncobj = f.file->private_data;
 725         drm_syncobj_get(syncobj);
 726
 727         idr_preload(GFP_KERNEL);
 728         spin_lock(&file_private->syncobj_table_lock);
 729         ret = idr_alloc(&file_private->syncobj_idr, syncobj, 1, 0, GFP_NOWAIT);
 730         spin_unlock(&file_private->syncobj_table_lock);
 731         idr_preload_end();
 732
 733         if (ret > 0) {
 734                 *handle = ret;
 735                 ret = 0;
 736         } else
 737                 drm_syncobj_put(syncobj);
 738
 739         fdput(f);
 740         return ret;
 741 }
 742
 743 static int drm_syncobj_import_sync_file_fence(struct drm_file *file_private,
 744                                               int fd, int handle)
 745 {
 746         struct dma_fence *fence = sync_file_get_fence(fd);
 747         struct drm_syncobj *syncobj;
 748
 749         if (!fence)
 750                 return -EINVAL;
 751
 752         syncobj = drm_syncobj_find(file_private, handle);
 753         if (!syncobj) {
 754                 dma_fence_put(fence);
 755                 return -ENOENT;
 756         }
 757
 758         drm_syncobj_replace_fence(syncobj, fence);
 759         dma_fence_put(fence);
 760         drm_syncobj_put(syncobj);
 761         return 0;
 762 }
 763
 764 static int drm_syncobj_export_sync_file(struct drm_file *file_private,
 765                                         int handle, int *p_fd)
 766 {
 767         int ret;
 768         struct dma_fence *fence;
 769         struct sync_file *sync_file;
 770         int fd = get_unused_fd_flags(O_CLOEXEC);
 771
 772         if (fd < 0)
 773                 return fd;
 774
 775         ret = drm_syncobj_find_fence(file_private, handle, 0, 0, &fence);
 776         if (ret)
 777                 goto err_put_fd;
 778
 779         sync_file = sync_file_create(fence);
 780
 781         dma_fence_put(fence);
 782
 783         if (!sync_file) {
 784                 ret = -EINVAL;
 785                 goto err_put_fd;
 786         }
 787
 788         fd_install(fd, sync_file->file);
 789
 790         *p_fd = fd;
 791         return 0;
 792 err_put_fd:
 793         put_unused_fd(fd);
 794         return ret;
 795 }
 796 /**
 797  * drm_syncobj_open - initializes syncobj file-private structures at devnode open time
 798  * @file_private: drm file-private structure to set up
 799  *
 800  * Called at device open time, sets up the structure for handling refcounting
 801  * of sync objects.
 802  */
 803 void
 804 drm_syncobj_open(struct drm_file *file_private)
 805 {
 806         idr_init_base(&file_private->syncobj_idr, 1);
 807         spin_lock_init(&file_private->syncobj_table_lock);
 808 }
 809
 810 static int
 811 drm_syncobj_release_handle(int id, void *ptr, void *data)
 812 {
 813         struct drm_syncobj *syncobj = ptr;
 814
 815         drm_syncobj_put(syncobj);
 816         return 0;
 817 }
 818
 819 /**
 820  * drm_syncobj_release - release file-private sync object resources
 821  * @file_private: drm file-private structure to clean up
 822  *
 823  * Called at close time when the filp is going away.
 824  *
 825  * Releases any remaining references on objects by this filp.
 826  */
 827 void
 828 drm_syncobj_release(struct drm_file *file_private)
 829 {
 830         idr_for_each(&file_private->syncobj_idr,
 831                      &drm_syncobj_release_handle, file_private);
 832         idr_destroy(&file_private->syncobj_idr);
 833 }
 834
 835 int
 836 drm_syncobj_create_ioctl(struct drm_device *dev, void *data,
 837                          struct drm_file *file_private)
 838 {
 839         struct drm_syncobj_create *args = data;
 840
 841         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 842                 return -EOPNOTSUPP;
 843
 844         /* no valid flags yet */
 845         if (args->flags & ~DRM_SYNCOBJ_CREATE_SIGNALED)
 846                 return -EINVAL;
 847
 848         return drm_syncobj_create_as_handle(file_private,
 849                                             &args->handle, args->flags);
 850 }
 851
 852 int
 853 drm_syncobj_destroy_ioctl(struct drm_device *dev, void *data,
 854                           struct drm_file *file_private)
 855 {
 856         struct drm_syncobj_destroy *args = data;
 857
 858         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 859                 return -EOPNOTSUPP;
 860
 861         /* make sure padding is empty */
 862         if (args->pad)
 863                 return -EINVAL;
 864         return drm_syncobj_destroy(file_private, args->handle);
 865 }
 866
 867 int
 868 drm_syncobj_handle_to_fd_ioctl(struct drm_device *dev, void *data,
 869                                    struct drm_file *file_private)
 870 {
 871         struct drm_syncobj_handle *args = data;
 872
 873         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 874                 return -EOPNOTSUPP;
 875
 876         if (args->pad)
 877                 return -EINVAL;
 878
 879         if (args->flags != 0 &&
 880             args->flags != DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
 881                 return -EINVAL;
 882
 883         if (args->flags & DRM_SYNCOBJ_HANDLE_TO_FD_FLAGS_EXPORT_SYNC_FILE)
 884                 return drm_syncobj_export_sync_file(file_private, args->handle,
 885                                                     &args->fd);
 886
 887         return drm_syncobj_handle_to_fd(file_private, args->handle,
 888                                         &args->fd);
 889 }
 890
 891 int
 892 drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data,
 893                                    struct drm_file *file_private)
 894 {
 895         struct drm_syncobj_handle *args = data;
 896
 897         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
 898                 return -EOPNOTSUPP;
 899
 900         if (args->pad)
 901                 return -EINVAL;
 902
 903         if (args->flags != 0 &&
 904             args->flags != DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
 905                 return -EINVAL;
 906
 907         if (args->flags & DRM_SYNCOBJ_FD_TO_HANDLE_FLAGS_IMPORT_SYNC_FILE)
 908                 return drm_syncobj_import_sync_file_fence(file_private,
 909                                                           args->fd,
 910                                                           args->handle);
 911
 912         return drm_syncobj_fd_to_handle(file_private, args->fd,
 913                                         &args->handle);
 914 }
 915
 916 static int drm_syncobj_transfer_to_timeline(struct drm_file *file_private,
 917                                             struct drm_syncobj_transfer *args)
 918 {
 919         struct drm_syncobj *timeline_syncobj = NULL;
 920         struct dma_fence *fence, *tmp;
 921         struct dma_fence_chain *chain;
 922         int ret;
 923
 924         timeline_syncobj = drm_syncobj_find(file_private, args->dst_handle);
 925         if (!timeline_syncobj) {
 926                 return -ENOENT;
 927         }
 928         ret = drm_syncobj_find_fence(file_private, args->src_handle,
 929                                      args->src_point, args->flags,
 930                                      &tmp);
 931         if (ret)
 932                 goto err_put_timeline;
 933
 934         fence = dma_fence_unwrap_merge(tmp);
 935         dma_fence_put(tmp);
 936         if (!fence) {
 937                 ret = -ENOMEM;
 938                 goto err_put_timeline;
 939         }
 940
 941         chain = dma_fence_chain_alloc();
 942         if (!chain) {
 943                 ret = -ENOMEM;
 944                 goto err_free_fence;
 945         }
 946
 947         drm_syncobj_add_point(timeline_syncobj, chain, fence, args->dst_point);
 948 err_free_fence:
 949         dma_fence_put(fence);
 950 err_put_timeline:
 951         drm_syncobj_put(timeline_syncobj);
 952
 953         return ret;
 954 }
 955
 956 static int
 957 drm_syncobj_transfer_to_binary(struct drm_file *file_private,
 958                                struct drm_syncobj_transfer *args)
 959 {
 960         struct drm_syncobj *binary_syncobj = NULL;
 961         struct dma_fence *fence;
 962         int ret;
 963
 964         binary_syncobj = drm_syncobj_find(file_private, args->dst_handle);
 965         if (!binary_syncobj)
 966                 return -ENOENT;
 967         ret = drm_syncobj_find_fence(file_private, args->src_handle,
 968                                      args->src_point, args->flags, &fence);
 969         if (ret)
 970                 goto err;
 971         drm_syncobj_replace_fence(binary_syncobj, fence);
 972         dma_fence_put(fence);
 973 err:
 974         drm_syncobj_put(binary_syncobj);
 975
 976         return ret;
 977 }
 978 int
 979 drm_syncobj_transfer_ioctl(struct drm_device *dev, void *data,
 980                            struct drm_file *file_private)
 981 {
 982         struct drm_syncobj_transfer *args = data;
 983         int ret;
 984
 985         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
 986                 return -EOPNOTSUPP;
 987
 988         if (args->pad)
 989                 return -EINVAL;
 990
 991         if (args->dst_point)
 992                 ret = drm_syncobj_transfer_to_timeline(file_private, args);
 993         else
 994                 ret = drm_syncobj_transfer_to_binary(file_private, args);
 995
 996         return ret;
 997 }
 998
 999 static void syncobj_wait_fence_func(struct dma_fence *fence,
1000                                     struct dma_fence_cb *cb)
1001 {
1002         struct syncobj_wait_entry *wait =
1003                 container_of(cb, struct syncobj_wait_entry, fence_cb);
1004
1005         wake_up_process(wait->task);
1006 }
1007
1008 static void syncobj_wait_syncobj_func(struct drm_syncobj *syncobj,
1009                                       struct syncobj_wait_entry *wait)
1010 {
1011         struct dma_fence *fence;
1012
1013         /* This happens inside the syncobj lock */
1014         fence = rcu_dereference_protected(syncobj->fence,
1015                                           lockdep_is_held(&syncobj->lock));
1016         dma_fence_get(fence);
1017         if (!fence || dma_fence_chain_find_seqno(&fence, wait->point)) {
1018                 dma_fence_put(fence);
1019                 return;
1020         } else if (!fence) {
1021                 wait->fence = dma_fence_get_stub();
1022         } else {
1023                 wait->fence = fence;
1024         }
1025
1026         wake_up_process(wait->task);
1027         list_del_init(&wait->node);
1028 }
1029
1030 static signed long drm_syncobj_array_wait_timeout(struct drm_syncobj **syncobjs,
1031                                                   void __user *user_points,
1032                                                   uint32_t count,
1033                                                   uint32_t flags,
1034                                                   signed long timeout,
1035                                                   uint32_t *idx,
1036                                                   ktime_t *deadline)
1037 {
1038         struct syncobj_wait_entry *entries;
1039         struct dma_fence *fence;
1040         uint64_t *points;
1041         uint32_t signaled_count, i;
1042
1043         if (flags & (DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
1044                      DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE))
1045                 lockdep_assert_none_held_once();
1046
1047         points = kmalloc_array(count, sizeof(*points), GFP_KERNEL);
1048         if (points == NULL)
1049                 return -ENOMEM;
1050
1051         if (!user_points) {
1052                 memset(points, 0, count * sizeof(uint64_t));
1053
1054         } else if (copy_from_user(points, user_points,
1055                                   sizeof(uint64_t) * count)) {
1056                 timeout = -EFAULT;
1057                 goto err_free_points;
1058         }
1059
1060         entries = kcalloc(count, sizeof(*entries), GFP_KERNEL);
1061         if (!entries) {
1062                 timeout = -ENOMEM;
1063                 goto err_free_points;
1064         }
1065         /* Walk the list of sync objects and initialize entries.  We do
1066          * this up-front so that we can properly return -EINVAL if there is
1067          * a syncobj with a missing fence and then never have the chance of
1068          * returning -EINVAL again.
1069          */
1070         signaled_count = 0;
1071         for (i = 0; i < count; ++i) {
1072                 struct dma_fence *fence;
1073
1074                 entries[i].task = current;
1075                 entries[i].point = points[i];
1076                 fence = drm_syncobj_fence_get(syncobjs[i]);
1077                 if (!fence || dma_fence_chain_find_seqno(&fence, points[i])) {
1078                         dma_fence_put(fence);
1079                         if (flags & (DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
1080                                      DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE)) {
1081                                 continue;
1082                         } else {
1083                                 timeout = -EINVAL;
1084                                 goto cleanup_entries;
1085                         }
1086                 }
1087
1088                 if (fence)
1089                         entries[i].fence = fence;
1090                 else
1091                         entries[i].fence = dma_fence_get_stub();
1092
1093                 if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
1094                     dma_fence_is_signaled(entries[i].fence)) {
1095                         if (signaled_count == 0 && idx)
1096                                 *idx = i;
1097                         signaled_count++;
1098                 }
1099         }
1100
1101         if (signaled_count == count ||
1102             (signaled_count > 0 &&
1103              !(flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL)))
1104                 goto cleanup_entries;
1105
1106         /* There's a very annoying laxness in the dma_fence API here, in
1107          * that backends are not required to automatically report when a
1108          * fence is signaled prior to fence->ops->enable_signaling() being
1109          * called.  So here if we fail to match signaled_count, we need to
1110          * fallthough and try a 0 timeout wait!
1111          */
1112
1113         if (flags & (DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
1114                      DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE)) {
1115                 for (i = 0; i < count; ++i)
1116                         drm_syncobj_fence_add_wait(syncobjs[i], &entries[i]);
1117         }
1118
1119         if (deadline) {
1120                 for (i = 0; i < count; ++i) {
1121                         fence = entries[i].fence;
1122                         if (!fence)
1123                                 continue;
1124                         dma_fence_set_deadline(fence, *deadline);
1125                 }
1126         }
1127
1128         do {
1129                 set_current_state(TASK_INTERRUPTIBLE);
1130
1131                 signaled_count = 0;
1132                 for (i = 0; i < count; ++i) {
1133                         fence = entries[i].fence;
1134                         if (!fence)
1135                                 continue;
1136
1137                         if ((flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) ||
1138                             dma_fence_is_signaled(fence) ||
1139                             (!entries[i].fence_cb.func &&
1140                              dma_fence_add_callback(fence,
1141                                                     &entries[i].fence_cb,
1142                                                     syncobj_wait_fence_func))) {
1143                                 /* The fence has been signaled */
1144                                 if (flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) {
1145                                         signaled_count++;
1146                                 } else {
1147                                         if (idx)
1148                                                 *idx = i;
1149                                         goto done_waiting;
1150                                 }
1151                         }
1152                 }
1153
1154                 if (signaled_count == count)
1155                         goto done_waiting;
1156
1157                 if (timeout == 0) {
1158                         timeout = -ETIME;
1159                         goto done_waiting;
1160                 }
1161
1162                 if (signal_pending(current)) {
1163                         timeout = -ERESTARTSYS;
1164                         goto done_waiting;
1165                 }
1166
1167                 timeout = schedule_timeout(timeout);
1168         } while (1);
1169
1170 done_waiting:
1171         __set_current_state(TASK_RUNNING);
1172
1173 cleanup_entries:
1174         for (i = 0; i < count; ++i) {
1175                 drm_syncobj_remove_wait(syncobjs[i], &entries[i]);
1176                 if (entries[i].fence_cb.func)
1177                         dma_fence_remove_callback(entries[i].fence,
1178                                                   &entries[i].fence_cb);
1179                 dma_fence_put(entries[i].fence);
1180         }
1181         kfree(entries);
1182
1183 err_free_points:
1184         kfree(points);
1185
1186         return timeout;
1187 }
1188
1189 /**
1190  * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute value
1191  *
1192  * @timeout_nsec: timeout nsec component in ns, 0 for poll
1193  *
1194  * Calculate the timeout in jiffies from an absolute time in sec/nsec.
1195  */
1196 signed long drm_timeout_abs_to_jiffies(int64_t timeout_nsec)
1197 {
1198         ktime_t abs_timeout, now;
1199         u64 timeout_ns, timeout_jiffies64;
1200
1201         /* make 0 timeout means poll - absolute 0 doesn't seem valid */
1202         if (timeout_nsec == 0)
1203                 return 0;
1204
1205         abs_timeout = ns_to_ktime(timeout_nsec);
1206         now = ktime_get();
1207
1208         if (!ktime_after(abs_timeout, now))
1209                 return 0;
1210
1211         timeout_ns = ktime_to_ns(ktime_sub(abs_timeout, now));
1212
1213         timeout_jiffies64 = nsecs_to_jiffies64(timeout_ns);
1214         /*  clamp timeout to avoid infinite timeout */
1215         if (timeout_jiffies64 >= MAX_SCHEDULE_TIMEOUT - 1)
1216                 return MAX_SCHEDULE_TIMEOUT - 1;
1217
1218         return timeout_jiffies64 + 1;
1219 }
1220 EXPORT_SYMBOL(drm_timeout_abs_to_jiffies);
1221
1222 static int drm_syncobj_array_wait(struct drm_device *dev,
1223                                   struct drm_file *file_private,
1224                                   struct drm_syncobj_wait *wait,
1225                                   struct drm_syncobj_timeline_wait *timeline_wait,
1226                                   struct drm_syncobj **syncobjs, bool timeline,
1227                                   ktime_t *deadline)
1228 {
1229         signed long timeout = 0;
1230         uint32_t first = ~0;
1231
1232         if (!timeline) {
1233                 timeout = drm_timeout_abs_to_jiffies(wait->timeout_nsec);
1234                 timeout = drm_syncobj_array_wait_timeout(syncobjs,
1235                                                          NULL,
1236                                                          wait->count_handles,
1237                                                          wait->flags,
1238                                                          timeout, &first,
1239                                                          deadline);
1240                 if (timeout < 0)
1241                         return timeout;
1242                 wait->first_signaled = first;
1243         } else {
1244                 timeout = drm_timeout_abs_to_jiffies(timeline_wait->timeout_nsec);
1245                 timeout = drm_syncobj_array_wait_timeout(syncobjs,
1246                                                          u64_to_user_ptr(timeline_wait->points),
1247                                                          timeline_wait->count_handles,
1248                                                          timeline_wait->flags,
1249                                                          timeout, &first,
1250                                                          deadline);
1251                 if (timeout < 0)
1252                         return timeout;
1253                 timeline_wait->first_signaled = first;
1254         }
1255         return 0;
1256 }
1257
1258 static int drm_syncobj_array_find(struct drm_file *file_private,
1259                                   void __user *user_handles,
1260                                   uint32_t count_handles,
1261                                   struct drm_syncobj ***syncobjs_out)
1262 {
1263         uint32_t i, *handles;
1264         struct drm_syncobj **syncobjs;
1265         int ret;
1266
1267         handles = kmalloc_array(count_handles, sizeof(*handles), GFP_KERNEL);
1268         if (handles == NULL)
1269                 return -ENOMEM;
1270
1271         if (copy_from_user(handles, user_handles,
1272                            sizeof(uint32_t) * count_handles)) {
1273                 ret = -EFAULT;
1274                 goto err_free_handles;
1275         }
1276
1277         syncobjs = kmalloc_array(count_handles, sizeof(*syncobjs), GFP_KERNEL);
1278         if (syncobjs == NULL) {
1279                 ret = -ENOMEM;
1280                 goto err_free_handles;
1281         }
1282
1283         for (i = 0; i < count_handles; i++) {
1284                 syncobjs[i] = drm_syncobj_find(file_private, handles[i]);
1285                 if (!syncobjs[i]) {
1286                         ret = -ENOENT;
1287                         goto err_put_syncobjs;
1288                 }
1289         }
1290
1291         kfree(handles);
1292         *syncobjs_out = syncobjs;
1293         return 0;
1294
1295 err_put_syncobjs:
1296         while (i-- > 0)
1297                 drm_syncobj_put(syncobjs[i]);
1298         kfree(syncobjs);
1299 err_free_handles:
1300         kfree(handles);
1301
1302         return ret;
1303 }
1304
1305 static void drm_syncobj_array_free(struct drm_syncobj **syncobjs,
1306                                    uint32_t count)
1307 {
1308         uint32_t i;
1309
1310         for (i = 0; i < count; i++)
1311                 drm_syncobj_put(syncobjs[i]);
1312         kfree(syncobjs);
1313 }
1314
1315 int
1316 drm_syncobj_wait_ioctl(struct drm_device *dev, void *data,
1317                        struct drm_file *file_private)
1318 {
1319         struct drm_syncobj_wait *args = data;
1320         struct drm_syncobj **syncobjs;
1321         unsigned int possible_flags;
1322         ktime_t t, *tp = NULL;
1323         int ret = 0;
1324
1325         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
1326                 return -EOPNOTSUPP;
1327
1328         possible_flags = DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
1329                          DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
1330                          DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE;
1331
1332         if (args->flags & ~possible_flags)
1333                 return -EINVAL;
1334
1335         if (args->count_handles == 0)
1336                 return 0;
1337
1338         ret = drm_syncobj_array_find(file_private,
1339                                      u64_to_user_ptr(args->handles),
1340                                      args->count_handles,
1341                                      &syncobjs);
1342         if (ret < 0)
1343                 return ret;
1344
1345         if (args->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE) {
1346                 t = ns_to_ktime(args->deadline_nsec);
1347                 tp = &t;
1348         }
1349
1350         ret = drm_syncobj_array_wait(dev, file_private,
1351                                      args, NULL, syncobjs, false, tp);
1352
1353         drm_syncobj_array_free(syncobjs, args->count_handles);
1354
1355         return ret;
1356 }
1357
1358 int
1359 drm_syncobj_timeline_wait_ioctl(struct drm_device *dev, void *data,
1360                                 struct drm_file *file_private)
1361 {
1362         struct drm_syncobj_timeline_wait *args = data;
1363         struct drm_syncobj **syncobjs;
1364         unsigned int possible_flags;
1365         ktime_t t, *tp = NULL;
1366         int ret = 0;
1367
1368         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1369                 return -EOPNOTSUPP;
1370
1371         possible_flags = DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL |
1372                          DRM_SYNCOBJ_WAIT_FLAGS_WAIT_FOR_SUBMIT |
1373                          DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE |
1374                          DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE;
1375
1376         if (args->flags & ~possible_flags)
1377                 return -EINVAL;
1378
1379         if (args->count_handles == 0)
1380                 return 0;
1381
1382         ret = drm_syncobj_array_find(file_private,
1383                                      u64_to_user_ptr(args->handles),
1384                                      args->count_handles,
1385                                      &syncobjs);
1386         if (ret < 0)
1387                 return ret;
1388
1389         if (args->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_DEADLINE) {
1390                 t = ns_to_ktime(args->deadline_nsec);
1391                 tp = &t;
1392         }
1393
1394         ret = drm_syncobj_array_wait(dev, file_private,
1395                                      NULL, args, syncobjs, true, tp);
1396
1397         drm_syncobj_array_free(syncobjs, args->count_handles);
1398
1399         return ret;
1400 }
1401
1402 static void syncobj_eventfd_entry_fence_func(struct dma_fence *fence,
1403                                              struct dma_fence_cb *cb)
1404 {
1405         struct syncobj_eventfd_entry *entry =
1406                 container_of(cb, struct syncobj_eventfd_entry, fence_cb);
1407
1408         eventfd_signal(entry->ev_fd_ctx);
1409         syncobj_eventfd_entry_free(entry);
1410 }
1411
1412 static void
1413 syncobj_eventfd_entry_func(struct drm_syncobj *syncobj,
1414                            struct syncobj_eventfd_entry *entry)
1415 {
1416         int ret;
1417         struct dma_fence *fence;
1418
1419         /* This happens inside the syncobj lock */
1420         fence = dma_fence_get(rcu_dereference_protected(syncobj->fence, 1));
1421         if (!fence)
1422                 return;
1423
1424         ret = dma_fence_chain_find_seqno(&fence, entry->point);
1425         if (ret != 0) {
1426                 /* The given seqno has not been submitted yet. */
1427                 dma_fence_put(fence);
1428                 return;
1429         } else if (!fence) {
1430                 /* If dma_fence_chain_find_seqno returns 0 but sets the fence
1431                  * to NULL, it implies that the given seqno is signaled and a
1432                  * later seqno has already been submitted. Assign a stub fence
1433                  * so that the eventfd still gets signaled below.
1434                  */
1435                 fence = dma_fence_get_stub();
1436         }
1437
1438         list_del_init(&entry->node);
1439         entry->fence = fence;
1440
1441         if (entry->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE) {
1442                 eventfd_signal(entry->ev_fd_ctx);
1443                 syncobj_eventfd_entry_free(entry);
1444         } else {
1445                 ret = dma_fence_add_callback(fence, &entry->fence_cb,
1446                                              syncobj_eventfd_entry_fence_func);
1447                 if (ret == -ENOENT) {
1448                         eventfd_signal(entry->ev_fd_ctx);
1449                         syncobj_eventfd_entry_free(entry);
1450                 }
1451         }
1452 }
1453
1454 int
1455 drm_syncobj_eventfd_ioctl(struct drm_device *dev, void *data,
1456                           struct drm_file *file_private)
1457 {
1458         struct drm_syncobj_eventfd *args = data;
1459         struct drm_syncobj *syncobj;
1460         struct eventfd_ctx *ev_fd_ctx;
1461         struct syncobj_eventfd_entry *entry;
1462
1463         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1464                 return -EOPNOTSUPP;
1465
1466         if (args->flags & ~DRM_SYNCOBJ_WAIT_FLAGS_WAIT_AVAILABLE)
1467                 return -EINVAL;
1468
1469         if (args->pad)
1470                 return -EINVAL;
1471
1472         syncobj = drm_syncobj_find(file_private, args->handle);
1473         if (!syncobj)
1474                 return -ENOENT;
1475
1476         ev_fd_ctx = eventfd_ctx_fdget(args->fd);
1477         if (IS_ERR(ev_fd_ctx))
1478                 return PTR_ERR(ev_fd_ctx);
1479
1480         entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1481         if (!entry) {
1482                 eventfd_ctx_put(ev_fd_ctx);
1483                 return -ENOMEM;
1484         }
1485         entry->syncobj = syncobj;
1486         entry->ev_fd_ctx = ev_fd_ctx;
1487         entry->point = args->point;
1488         entry->flags = args->flags;
1489
1490         drm_syncobj_add_eventfd(syncobj, entry);
1491         drm_syncobj_put(syncobj);
1492
1493         return 0;
1494 }
1495
1496 int
1497 drm_syncobj_reset_ioctl(struct drm_device *dev, void *data,
1498                         struct drm_file *file_private)
1499 {
1500         struct drm_syncobj_array *args = data;
1501         struct drm_syncobj **syncobjs;
1502         uint32_t i;
1503         int ret;
1504
1505         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
1506                 return -EOPNOTSUPP;
1507
1508         if (args->pad != 0)
1509                 return -EINVAL;
1510
1511         if (args->count_handles == 0)
1512                 return -EINVAL;
1513
1514         ret = drm_syncobj_array_find(file_private,
1515                                      u64_to_user_ptr(args->handles),
1516                                      args->count_handles,
1517                                      &syncobjs);
1518         if (ret < 0)
1519                 return ret;
1520
1521         for (i = 0; i < args->count_handles; i++)
1522                 drm_syncobj_replace_fence(syncobjs[i], NULL);
1523
1524         drm_syncobj_array_free(syncobjs, args->count_handles);
1525
1526         return 0;
1527 }
1528
1529 int
1530 drm_syncobj_signal_ioctl(struct drm_device *dev, void *data,
1531                          struct drm_file *file_private)
1532 {
1533         struct drm_syncobj_array *args = data;
1534         struct drm_syncobj **syncobjs;
1535         uint32_t i;
1536         int ret;
1537
1538         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ))
1539                 return -EOPNOTSUPP;
1540
1541         if (args->pad != 0)
1542                 return -EINVAL;
1543
1544         if (args->count_handles == 0)
1545                 return -EINVAL;
1546
1547         ret = drm_syncobj_array_find(file_private,
1548                                      u64_to_user_ptr(args->handles),
1549                                      args->count_handles,
1550                                      &syncobjs);
1551         if (ret < 0)
1552                 return ret;
1553
1554         for (i = 0; i < args->count_handles; i++) {
1555                 ret = drm_syncobj_assign_null_handle(syncobjs[i]);
1556                 if (ret < 0)
1557                         break;
1558         }
1559
1560         drm_syncobj_array_free(syncobjs, args->count_handles);
1561
1562         return ret;
1563 }
1564
1565 int
1566 drm_syncobj_timeline_signal_ioctl(struct drm_device *dev, void *data,
1567                                   struct drm_file *file_private)
1568 {
1569         struct drm_syncobj_timeline_array *args = data;
1570         struct drm_syncobj **syncobjs;
1571         struct dma_fence_chain **chains;
1572         uint64_t *points;
1573         uint32_t i, j;
1574         int ret;
1575
1576         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1577                 return -EOPNOTSUPP;
1578
1579         if (args->flags != 0)
1580                 return -EINVAL;
1581
1582         if (args->count_handles == 0)
1583                 return -EINVAL;
1584
1585         ret = drm_syncobj_array_find(file_private,
1586                                      u64_to_user_ptr(args->handles),
1587                                      args->count_handles,
1588                                      &syncobjs);
1589         if (ret < 0)
1590                 return ret;
1591
1592         points = kmalloc_array(args->count_handles, sizeof(*points),
1593                                GFP_KERNEL);
1594         if (!points) {
1595                 ret = -ENOMEM;
1596                 goto out;
1597         }
1598         if (!u64_to_user_ptr(args->points)) {
1599                 memset(points, 0, args->count_handles * sizeof(uint64_t));
1600         } else if (copy_from_user(points, u64_to_user_ptr(args->points),
1601                                   sizeof(uint64_t) * args->count_handles)) {
1602                 ret = -EFAULT;
1603                 goto err_points;
1604         }
1605
1606         chains = kmalloc_array(args->count_handles, sizeof(void *), GFP_KERNEL);
1607         if (!chains) {
1608                 ret = -ENOMEM;
1609                 goto err_points;
1610         }
1611         for (i = 0; i < args->count_handles; i++) {
1612                 chains[i] = dma_fence_chain_alloc();
1613                 if (!chains[i]) {
1614                         for (j = 0; j < i; j++)
1615                                 dma_fence_chain_free(chains[j]);
1616                         ret = -ENOMEM;
1617                         goto err_chains;
1618                 }
1619         }
1620
1621         for (i = 0; i < args->count_handles; i++) {
1622                 struct dma_fence *fence = dma_fence_get_stub();
1623
1624                 drm_syncobj_add_point(syncobjs[i], chains[i],
1625                                       fence, points[i]);
1626                 dma_fence_put(fence);
1627         }
1628 err_chains:
1629         kfree(chains);
1630 err_points:
1631         kfree(points);
1632 out:
1633         drm_syncobj_array_free(syncobjs, args->count_handles);
1634
1635         return ret;
1636 }
1637
1638 int drm_syncobj_query_ioctl(struct drm_device *dev, void *data,
1639                             struct drm_file *file_private)
1640 {
1641         struct drm_syncobj_timeline_array *args = data;
1642         struct drm_syncobj **syncobjs;
1643         uint64_t __user *points = u64_to_user_ptr(args->points);
1644         uint32_t i;
1645         int ret;
1646
1647         if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE))
1648                 return -EOPNOTSUPP;
1649
1650         if (args->flags & ~DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED)
1651                 return -EINVAL;
1652
1653         if (args->count_handles == 0)
1654                 return -EINVAL;
1655
1656         ret = drm_syncobj_array_find(file_private,
1657                                      u64_to_user_ptr(args->handles),
1658                                      args->count_handles,
1659                                      &syncobjs);
1660         if (ret < 0)
1661                 return ret;
1662
1663         for (i = 0; i < args->count_handles; i++) {
1664                 struct dma_fence_chain *chain;
1665                 struct dma_fence *fence;
1666                 uint64_t point;
1667
1668                 fence = drm_syncobj_fence_get(syncobjs[i]);
1669                 chain = to_dma_fence_chain(fence);
1670                 if (chain) {
1671                         struct dma_fence *iter, *last_signaled =
1672                                 dma_fence_get(fence);
1673
1674                         if (args->flags &
1675                             DRM_SYNCOBJ_QUERY_FLAGS_LAST_SUBMITTED) {
1676                                 point = fence->seqno;
1677                         } else {
1678                                 dma_fence_chain_for_each(iter, fence) {
1679                                         if (iter->context != fence->context) {
1680                                                 dma_fence_put(iter);
1681                                                 /* It is most likely that timeline has
1682                                                 * unorder points. */
1683                                                 break;
1684                                         }
1685                                         dma_fence_put(last_signaled);
1686                                         last_signaled = dma_fence_get(iter);
1687                                 }
1688                                 point = dma_fence_is_signaled(last_signaled) ?
1689                                         last_signaled->seqno :
1690                                         to_dma_fence_chain(last_signaled)->prev_seqno;
1691                         }
1692                         dma_fence_put(last_signaled);
1693                 } else {
1694                         point = 0;
1695                 }
1696                 dma_fence_put(fence);
1697                 ret = copy_to_user(&points[i], &point, sizeof(uint64_t));
1698                 ret = ret ? -EFAULT : 0;
1699                 if (ret)
1700                         break;
1701         }
1702         drm_syncobj_array_free(syncobjs, args->count_handles);
1703
1704         return ret;
1705 }