[igt-dev] [PATCH i-g-t 2/2] i915/gem_softpin: Check full placement control under full-ppgtt

[Chris Wilson]

With full-ppgtt, userspacew has complete control over their GTT. Verify
that we can place an object at the very beginning and the very end of
our GTT.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 tests/i915/gem_softpin.c | 45 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/tests/i915/gem_softpin.c b/tests/i915/gem_softpin.c
index fcaf8ef30..a530e89d3 100644
--- a/tests/i915/gem_softpin.c
+++ b/tests/i915/gem_softpin.c
@@ -97,6 +97,47 @@ static void test_invalid(int fd)
 	}
 }
 
+static uint32_t batch_create(int i915, uint64_t *sz)
+{
+	const uint32_t bbe = MI_BATCH_BUFFER_END;
+	struct drm_i915_gem_create create = {
+		.size = sizeof(bbe),
+	};
+
+	if (igt_ioctl(i915, DRM_IOCTL_I915_GEM_CREATE, &create)) {
+		igt_assert_eq(errno, 0);
+		return 0;
+	}
+
+	gem_write(i915, create.handle, 0, &bbe, sizeof(bbe));
+
+	*sz = create.size;
+	return create.handle;
+}
+
+static void test_zero(int i915)
+{
+	uint64_t sz;
+	struct drm_i915_gem_exec_object2 object = {
+		.handle = batch_create(i915, &sz),
+		.flags = EXEC_OBJECT_PINNED | EXEC_OBJECT_SUPPORTS_48B_ADDRESS,
+	};
+	struct drm_i915_gem_execbuffer2 execbuf = {
+		.buffers_ptr = to_user_pointer(&object),
+		.buffer_count = 1,
+	};
+
+	/* Under full-ppgtt, we have complete control of the GTT */
+
+	object.offset = 0;
+	gem_execbuf(i915, &execbuf);
+
+	object.offset = gem_aperture_size(i915) - sz;
+	gem_close(i915, object.handle);
+
+	gem_close(i915, object.handle);
+}
+
 static void test_softpin(int fd)
 {
 	const uint32_t size = 1024 * 1024;
@@ -559,6 +600,10 @@ igt_main
 
 	igt_subtest("invalid")
 		test_invalid(fd);
+	igt_subtest("zero") {
+		igt_require(gem_uses_full_ppgtt(fd));
+		test_zero(fd);
+	}
 	igt_subtest("softpin")
 		test_softpin(fd);
 	igt_subtest("overlap")
-- 
2.29.2