static int __init dma_resv_lockdep()

in dma-resv.c [692:730]

• 33 lines of code
• 3 McCabe index (conditional complexity)

static int __init dma_resv_lockdep(void)
{
	struct mm_struct *mm = mm_alloc();
	struct ww_acquire_ctx ctx;
	struct dma_resv obj;
	struct address_space mapping;
	int ret;

	if (!mm)
		return -ENOMEM;

	dma_resv_init(&obj);
	address_space_init_once(&mapping);

	mmap_read_lock(mm);
	ww_acquire_init(&ctx, &reservation_ww_class);
	ret = dma_resv_lock(&obj, &ctx);
	if (ret == -EDEADLK)
		dma_resv_lock_slow(&obj, &ctx);
	fs_reclaim_acquire(GFP_KERNEL);
	/* for unmap_mapping_range on trylocked buffer objects in shrinkers */
	i_mmap_lock_write(&mapping);
	i_mmap_unlock_write(&mapping);
#ifdef CONFIG_MMU_NOTIFIER
	lock_map_acquire(&__mmu_notifier_invalidate_range_start_map);
	__dma_fence_might_wait();
	lock_map_release(&__mmu_notifier_invalidate_range_start_map);
#else
	__dma_fence_might_wait();
#endif
	fs_reclaim_release(GFP_KERNEL);
	ww_mutex_unlock(&obj.lock);
	ww_acquire_fini(&ctx);
	mmap_read_unlock(mm);

	mmput(mm);

	return 0;
}