8 	struct intel_ring *ring;  in mock_ring()  local
10 	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);  in mock_ring()
11 	if (!ring)  in mock_ring()
14 	kref_init(&ring->ref);  in mock_ring()
15 	ring->size = sz;  in mock_ring()
16 	ring->wrap = BITS_PER_TYPE(ring->size) - ilog2(sz);  in mock_ring()
17 	ring->effective_size = sz;  in mock_ring()
18 	ring->vaddr = (void *)(ring + 1);  in mock_ring()
19 	atomic_set(&ring->pin_count, 1);  in mock_ring()
21 	intel_ring_update_space(ring);  in mock_ring()
23 	return ring;  in mock_ring()
26 static void mock_ring_free(struct intel_ring *ring)  in mock_ring_free()  argument
28 	kfree(ring);  in mock_ring_free()
31 static int check_ring_direction(struct intel_ring *ring,  in check_ring_direction()  argument
37 	result = intel_ring_direction(ring, next, prev);  in check_ring_direction()
52 static int check_ring_step(struct intel_ring *ring, u32 x, u32 step)  in check_ring_step()  argument
54 	u32 prev = x, next = intel_ring_wrap(ring, x + step);  in check_ring_step()
57 	err |= check_ring_direction(ring, next, next,  0);  in check_ring_step()
58 	err |= check_ring_direction(ring, prev, prev,  0);  in check_ring_step()
59 	err |= check_ring_direction(ring, next, prev,  1);  in check_ring_step()
60 	err |= check_ring_direction(ring, prev, next, -1);  in check_ring_step()
65 static int check_ring_offset(struct intel_ring *ring, u32 x, u32 step)  in check_ring_offset()  argument
69 	err |= check_ring_step(ring, x, step);  in check_ring_offset()
70 	err |= check_ring_step(ring, intel_ring_wrap(ring, x + 1), step);  in check_ring_offset()
71 	err |= check_ring_step(ring, intel_ring_wrap(ring, x - 1), step);  in check_ring_offset()
78 	struct intel_ring *ring;  in igt_ring_direction()  local
82 	ring = mock_ring(2 * half);  in igt_ring_direction()
83 	if (!ring)  in igt_ring_direction()
86 	GEM_BUG_ON(ring->size != 2 * half);  in igt_ring_direction()
90 		err |= check_ring_offset(ring, 0, step);  in igt_ring_direction()
91 		err |= check_ring_offset(ring, half, step);  in igt_ring_direction()
93 	err |= check_ring_step(ring, 0, half - 64);  in igt_ring_direction()
96 	err |= check_ring_offset(ring, 0, 2 * half + 64);  in igt_ring_direction()
97 	err |= check_ring_offset(ring, 3 * half, 1);  in igt_ring_direction()
99 	mock_ring_free(ring);  in igt_ring_direction()