Quelle  i915_sw_fence_work.c   Sprache: C

// SPDX-License-Identifier: MIT

/*
 * Copyright © 2019 Intel Corporation
 */

#include "i915_sw_fence_work.h"

static void fence_complete(struct dma_fence_work *f)
{
 if (f->ops->release)
  f->ops->release(f);
 dma_fence_signal(&f->dma);
}

static void fence_work(struct work_struct *work)
{
 struct dma_fence_work *f = container_of(work, typeof(*f), work);

 f->ops->work(f);

 fence_complete(f);
 dma_fence_put(&f->dma);
}

static int
fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
{
 struct dma_fence_work *f = container_of(fence, typeof(*f), chain);

 switch (state) {
 case FENCE_COMPLETE:
  if (fence->error)
   dma_fence_set_error(&f->dma, fence->error);

  if (!f->dma.error) {
   dma_fence_get(&f->dma);
   if (test_bit(DMA_FENCE_WORK_IMM, &f->dma.flags))
    fence_work(&f->work);
   else
    queue_work(system_unbound_wq, &f->work);
  } else {
   fence_complete(f);
  }
  break;

 case FENCE_FREE:
  dma_fence_put(&f->dma);
  break;
 }

 return NOTIFY_DONE;
}

static const char *get_driver_name(struct dma_fence *fence)
{
 return "dma-fence";
}

static const char *get_timeline_name(struct dma_fence *fence)
{
 struct dma_fence_work *f = container_of(fence, typeof(*f), dma);

 return f->ops->name ?: "work";
}

static void fence_release(struct dma_fence *fence)
{
 struct dma_fence_work *f = container_of(fence, typeof(*f), dma);

 i915_sw_fence_fini(&f->chain);

 BUILD_BUG_ON(offsetof(typeof(*f), dma));
 dma_fence_free(&f->dma);
}

static const struct dma_fence_ops fence_ops = {
 .get_driver_name = get_driver_name,
 .get_timeline_name = get_timeline_name,
 .release = fence_release,
};

void dma_fence_work_init(struct dma_fence_work *f,
    const struct dma_fence_work_ops *ops)
{
 f->ops = ops;
 spin_lock_init(&f->lock);
 dma_fence_init(&f->dma, &fence_ops, &f->lock, 0, 0);
 i915_sw_fence_init(&f->chain, fence_notify);
 INIT_WORK(&f->work, fence_work);
}

int dma_fence_work_chain(struct dma_fence_work *f, struct dma_fence *signal)
{
 if (!signal)
  return 0;

 return __i915_sw_fence_await_dma_fence(&f->chain, signal, &f->cb);
}