Example #1
0
static void
depth_first_traverse_page_table_recursive(
    generic_page_table_entry_t *table, int level, 
    depth_first_traversal_callback_t callback, void *arg)
{
    int i;
    for (i = 0; i < get_page_table_size(table); i++) {
        generic_page_table_entry_t* entry = &table[i];
        if (entry->present) {
            int pfns;
            int j;
            if (level == 1) {
                pfns = (4 << 10) >> 12;   /* single 4KB page */
            } else if (level == 2 && entry->size) {
/* Simulates SNA behaviour using negative self-relocations for
 * STATE_BASE_ADDRESS command packets. If they wrap around (to values greater
 * than the total size of the GTT), the GPU will hang.
 * See https://bugs.freedesktop.org/show_bug.cgi?id=78533
 */
static int negative_reloc(int fd, unsigned flags)
{
	struct drm_i915_gem_execbuffer2 execbuf;
	struct drm_i915_gem_exec_object2 gem_exec[2];
	struct drm_i915_gem_relocation_entry gem_reloc[1000];
	uint64_t gtt_max = get_page_table_size(fd);
	uint32_t buf[1024] = {MI_BATCH_BUFFER_END};
	int i;

#define BIAS (256*1024)

	igt_require(intel_gen(intel_get_drm_devid(fd)) >= 7);

	memset(gem_exec, 0, sizeof(gem_exec));
	gem_exec[0].handle = gem_create(fd, 4096);
	gem_write(fd, gem_exec[0].handle, 0, buf, 8);

	gem_reloc[0].offset = 1024;
	gem_reloc[0].delta = 0;
	gem_reloc[0].target_handle = gem_exec[0].handle;
	gem_reloc[0].read_domains = I915_GEM_DOMAIN_COMMAND;

	gem_exec[1].handle = gem_create(fd, 4096);
	gem_write(fd, gem_exec[1].handle, 0, buf, 8);
	gem_exec[1].relocation_count = 1;
	gem_exec[1].relocs_ptr = (uintptr_t)gem_reloc;

	memset(&execbuf, 0, sizeof(execbuf));
	execbuf.buffers_ptr = (uintptr_t)gem_exec;
	execbuf.buffer_count = 2;
	execbuf.batch_len = 8;

	do_or_die(drmIoctl(fd,
			   DRM_IOCTL_I915_GEM_EXECBUFFER2,
			   &execbuf));
	gem_close(fd, gem_exec[1].handle);

	igt_info("Found offset %lld for 4k batch\n", (long long)gem_exec[0].offset);
	/*
	 * Ideally we'd like to be able to control where the kernel is going to
	 * place the buffer. We don't SKIP here because it causes the test
	 * to "randomly" flip-flop between the SKIP and PASS states.
	 */
	if (gem_exec[0].offset < BIAS) {
		igt_info("Offset is below BIAS, not testing anything\n");
		return 0;
	}

	memset(gem_reloc, 0, sizeof(gem_reloc));
	for (i = 0; i < sizeof(gem_reloc)/sizeof(gem_reloc[0]); i++) {
		gem_reloc[i].offset = 8 + 4*i;
		gem_reloc[i].delta = -BIAS*i/1024;
		gem_reloc[i].target_handle = flags & USE_LUT ? 0 : gem_exec[0].handle;
		gem_reloc[i].read_domains = I915_GEM_DOMAIN_COMMAND;
	}

	gem_exec[0].relocation_count = sizeof(gem_reloc)/sizeof(gem_reloc[0]);
	gem_exec[0].relocs_ptr = (uintptr_t)gem_reloc;

	execbuf.buffer_count = 1;
	execbuf.flags = flags & USE_LUT;
	do_or_die(drmIoctl(fd,
			   DRM_IOCTL_I915_GEM_EXECBUFFER2,
			   &execbuf));

	igt_info("Batch is now at offset %lld\n", (long long)gem_exec[0].offset);

	gem_read(fd, gem_exec[0].handle, 0, buf, sizeof(buf));
	gem_close(fd, gem_exec[0].handle);

	for (i = 0; i < sizeof(gem_reloc)/sizeof(gem_reloc[0]); i++)
		igt_assert(buf[2 + i] < gtt_max);

	return 0;
}