[igt-dev] [PATCH i-g-t] i915/gem_exec_reloc: Verify relocations with pinned scanout framebuffers

[Chris Wilson]

In light of the VT-d workarounds, we may introduce padding around the
scanout vma. This should not affect relocations referencing the scanout
on !full-ppgtt where we leak the GGTT address of scanout to users.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld at intel.com>
Reviewed-by: Matthew Auld <matthew.auld at intel.com>
---
 tests/i915/gem_exec_reloc.c | 102 ++++++++++++++++++++++++++++++++++++
 1 file changed, 102 insertions(+)

diff --git a/tests/i915/gem_exec_reloc.c b/tests/i915/gem_exec_reloc.c
index cc9b8cd6d..23057f76e 100644
--- a/tests/i915/gem_exec_reloc.c
+++ b/tests/i915/gem_exec_reloc.c
@@ -26,7 +26,9 @@
 
 #include "i915/gem.h"
 #include "igt.h"
+#include "igt_device.h"
 #include "igt_dummyload.h"
+#include "igt_kms.h"
 #include "sw_sync.h"
 
 IGT_TEST_DESCRIPTION("Basic sanity check of execbuf-ioctl relocations.");
@@ -1286,6 +1288,83 @@ static void concurrent(int i915, int num_common)
 	igt_assert_eq(result, 0);
 }
 
+static uint32_t
+pin_scanout(igt_display_t *dpy, igt_output_t *output, struct igt_fb *fb)
+{
+	drmModeModeInfoPtr mode = igt_output_get_mode(output);
+	igt_plane_t *primary;
+
+	igt_create_pattern_fb(dpy->drm_fd, mode->hdisplay, mode->vdisplay,
+			      DRM_FORMAT_XRGB8888,
+			      LOCAL_I915_FORMAT_MOD_X_TILED, fb);
+
+	primary = igt_output_get_plane_type(output, DRM_PLANE_TYPE_PRIMARY);
+	igt_plane_set_fb(primary, fb);
+
+	igt_display_commit2(dpy, COMMIT_LEGACY);
+
+	return fb->gem_handle;
+}
+
+static void scanout(int i915,
+		    igt_display_t *dpy,
+		    const struct intel_execution_engine2 *e)
+{
+	struct drm_i915_gem_relocation_entry reloc;
+	struct drm_i915_gem_exec_object2 obj[2] = {
+		[1] = { .handle = batch_create(i915) },
+	};
+	struct drm_i915_gem_execbuffer2 execbuf = {
+		.buffers_ptr = to_user_pointer(obj),
+		.buffer_count = 2,
+		.flags = e->flags,
+	};
+	igt_output_t *output;
+	struct igt_fb fb;
+	uint64_t *map;
+
+	igt_display_reset(dpy);
+
+	output = igt_get_single_output_for_pipe(dpy, PIPE_A);
+	igt_require(output);
+	igt_output_set_pipe(output, PIPE_A);
+
+	/*
+	 * Find where the scanout is in our GTT; on !full-ppgtt this will be
+	 * the actual GGTT address of the scanout.
+	 */
+	obj[0].handle = pin_scanout(dpy, output, &fb);
+	gem_execbuf(i915, &execbuf);
+	igt_info("Scanout GTT address: %#llx\n", obj[0].offset);
+
+	/* Relocations should match the scanout address */
+	reloc.target_handle = obj[0].handle;
+	reloc.delta = 0;
+	reloc.presumed_offset = -1;
+	reloc.offset = 4000;
+	obj[1].relocation_count = 1;
+	obj[1].relocs_ptr = to_user_pointer(&reloc);
+	gem_execbuf(i915, &execbuf);
+	igt_info("Reloc address: %#llx\n", reloc.presumed_offset);
+	igt_assert_eq_u64(reloc.presumed_offset, obj[0].offset);
+
+	/* The address written into the batch should match the relocation */
+	gem_sync(i915, obj[1].handle);
+	map = gem_mmap__device_coherent(i915, obj[1].handle,
+					0, 4096, PROT_WRITE);
+	igt_assert_eq_u64(map[500], obj[0].offset);
+	munmap(map, 4096);
+
+	/* And finally softpinning with the scanout address should work */
+	obj[0].flags |= EXEC_OBJECT_PINNED;
+	obj[1].relocation_count = 0;
+	gem_execbuf(i915, &execbuf);
+	igt_assert_eq_u64(obj[0].offset, reloc.presumed_offset);
+
+	gem_close(i915, obj[1].handle);
+	igt_remove_fb(dpy->drm_fd, &fb);
+}
+
 #define I915_GEM_GPU_DOMAINS \
 	(I915_GEM_DOMAIN_RENDER | \
 	 I915_GEM_DOMAIN_SAMPLER | \
@@ -1511,6 +1590,29 @@ igt_main
 	igt_subtest("invalid-domains")
 		invalid_domains(fd);
 
+	igt_subtest_group {
+		igt_display_t display = {
+			.drm_fd = fd,
+			.n_pipes = IGT_MAX_PIPES
+		};
+
+		igt_fixture {
+			igt_device_set_master(fd);
+			kmstest_set_vt_graphics_mode();
+			igt_display_require(&display, fd);
+		}
+
+		igt_subtest_with_dynamic("basic-scanout") {
+			__for_each_physical_engine(fd, e) {
+				igt_dynamic_f("%s", e->name)
+					scanout(fd, &display, e);
+			}
+		}
+
+		igt_fixture
+			igt_display_fini(&display);
+	}
+
 	igt_fixture
 		close(fd);
 }
-- 
2.30.0