diff --git a/lib/drmtest.c b/lib/drmtest.c
index d526f38b..376e4ac5 100644
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -169,3 +169,22 @@ void gem_read(int fd, uint32_t handle, uint32_t offset, void *buf, uint32_t leng
 	assert(ret == 0);
 }
 
+void gem_set_domain(int fd, uint32_t handle,
+		    uint32_t read_domains, uint32_t write_domain)
+{
+	struct drm_i915_gem_set_domain set_domain;
+	int ret;
+
+	set_domain.handle = handle;
+	set_domain.read_domains = read_domains;
+	set_domain.write_domain = write_domain;
+
+	ret = drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
+	assert(ret == 0);
+}
+
+void gem_sync(int fd, uint32_t handle)
+{
+	gem_set_domain(fd, handle, I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
+}
+
diff --git a/lib/drmtest.h b/lib/drmtest.h
index 299570fd..794e08bc 100644
--- a/lib/drmtest.h
+++ b/lib/drmtest.h
@@ -41,3 +41,6 @@ void gem_set_tiling(int fd, uint32_t handle, int tiling, int stride);
 void gem_close(int fd, uint32_t handle);
 void gem_write(int fd, uint32_t handle, uint32_t offset,  const void *buf, uint32_t size);
 void gem_read(int fd, uint32_t handle, uint32_t offset, void *buf, uint32_t size);
+void gem_set_domain(int fd, uint32_t handle,
+		    uint32_t read_domains, uint32_t write_domain);
+void gem_sync(int fd, uint32_t handle);
diff --git a/tests/gem_exec_blt.c b/tests/gem_exec_blt.c
index 415b8826..91f7d215 100644
--- a/tests/gem_exec_blt.c
+++ b/tests/gem_exec_blt.c
@@ -137,17 +137,6 @@ static int gem_linear_blt(uint32_t *batch,
 	return (b+2 - batch) * sizeof(uint32_t);
 }
 
-static void gem_sync(int fd, uint32_t handle)
-{
-	struct drm_i915_gem_set_domain set_domain;
-
-	set_domain.handle = handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_GTT;
-	set_domain.write_domain = I915_GEM_DOMAIN_GTT;
-
-	drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
-}
-
 static int gem_exec(int fd, struct drm_i915_gem_execbuffer2 *execbuf, int loops)
 {
 	int ret = 0;
diff --git a/tests/gem_exec_faulting_reloc.c b/tests/gem_exec_faulting_reloc.c
index d584e646..013ee79a 100644
--- a/tests/gem_exec_faulting_reloc.c
+++ b/tests/gem_exec_faulting_reloc.c
@@ -162,17 +162,6 @@ static int gem_linear_blt(uint32_t *batch,
 	return (b+2 - batch) * sizeof(uint32_t);
 }
 
-static void gem_sync(int fd, uint32_t handle)
-{
-	struct drm_i915_gem_set_domain set_domain;
-
-	set_domain.handle = handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_GTT;
-	set_domain.write_domain = I915_GEM_DOMAIN_GTT;
-
-	drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
-}
-
 static void gem_exec(int fd, struct drm_i915_gem_execbuffer2 *execbuf)
 {
 	int ret;
diff --git a/tests/gem_exec_nop.c b/tests/gem_exec_nop.c
index b6c361e4..d13756b2 100644
--- a/tests/gem_exec_nop.c
+++ b/tests/gem_exec_nop.c
@@ -55,17 +55,6 @@ static uint32_t gem_create(int fd, int size)
 	return create.handle;
 }
 
-static void gem_sync(int fd, uint32_t handle)
-{
-	struct drm_i915_gem_set_domain set_domain;
-
-	set_domain.handle = handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_GTT;
-	set_domain.write_domain = I915_GEM_DOMAIN_GTT;
-
-	drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
-}
-
 static double elapsed(const struct timeval *start,
 		      const struct timeval *end,
 		      int loop)
diff --git a/tests/gem_fence_thrash.c b/tests/gem_fence_thrash.c
index 7b679369..2065ac65 100644
--- a/tests/gem_fence_thrash.c
+++ b/tests/gem_fence_thrash.c
@@ -58,7 +58,6 @@ bo_create (int fd)
 {
 	struct drm_i915_gem_create create;
 	struct drm_i915_gem_set_tiling tiling;
-	struct drm_i915_gem_set_domain domain;
 	struct drm_i915_gem_mmap_gtt mmap_arg;
 	void *ptr;
 	int handle;
@@ -88,12 +87,7 @@ bo_create (int fd)
 	assert (ptr != MAP_FAILED);
 
 	/* XXX: mmap_gtt pulls the bo into the GTT read domain. */
-	memset(&domain, 0, sizeof(domain));
-	domain.handle = handle;
-	domain.read_domains = I915_GEM_DOMAIN_GTT;
-	domain.write_domain = I915_GEM_DOMAIN_GTT;
-	ret = ioctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &domain);
-	assert (ret == 0);
+	gem_sync(fd, handle);
 
 	return ptr;
 }
diff --git a/tests/gem_gtt_speed.c b/tests/gem_gtt_speed.c
index 8e3750d7..3f5bd0b1 100644
--- a/tests/gem_gtt_speed.c
+++ b/tests/gem_gtt_speed.c
@@ -79,17 +79,6 @@ static double elapsed(const struct timeval *start,
 	return (1e6*(end->tv_sec - start->tv_sec) + (end->tv_usec - start->tv_usec))/loop;
 }
 
-static void gem_sync(int fd, uint32_t handle)
-{
-	struct drm_i915_gem_set_domain set_domain;
-
-	set_domain.handle = handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_GTT;
-	set_domain.write_domain = I915_GEM_DOMAIN_GTT;
-
-	drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
-}
-
 int main(int argc, char **argv)
 {
 	struct timeval start, end;
diff --git a/tests/gem_mmap_gtt.c b/tests/gem_mmap_gtt.c
index f817f14b..e8135871 100644
--- a/tests/gem_mmap_gtt.c
+++ b/tests/gem_mmap_gtt.c
@@ -57,15 +57,7 @@ static uint32_t gem_create(int fd, int size)
 
 static void set_domain(int fd, uint32_t handle)
 {
-	struct drm_i915_gem_set_domain set_domain;
-	int ret;
-
-	set_domain.handle = handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_GTT;
-	set_domain.write_domain = I915_GEM_DOMAIN_GTT;
-
-	ret = drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
-	assert(ret == 0);
+	gem_set_domain(fd, handle, I915_GEM_DOMAIN_GTT, I915_GEM_DOMAIN_GTT);
 }
 
 static void *
diff --git a/tests/gem_stress.c b/tests/gem_stress.c
index 64dca6c9..f72bd13f 100644
--- a/tests/gem_stress.c
+++ b/tests/gem_stress.c
@@ -190,20 +190,8 @@ void keep_gpu_busy(void)
 
 static void set_to_cpu_domain(struct scratch_buf *buf, int writing)
 {
-	struct drm_i915_gem_set_domain set_domain;
-	int ret;
-
-	set_domain.handle = buf->bo->handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_CPU;
-	if (writing)
-		set_domain.write_domain = I915_GEM_DOMAIN_CPU;
-	else
-		set_domain.write_domain = 0;
-
-	ret = drmIoctl(drm_fd,
-		       DRM_IOCTL_I915_GEM_SET_DOMAIN,
-		       &set_domain);
-	assert(ret == 0);
+	gem_set_domain(drm_fd, buf->bo->handle, I915_GEM_DOMAIN_CPU,
+		       writing ? I915_GEM_DOMAIN_CPU : 0);
 }
 
 static unsigned int copyfunc_seq = 0;
diff --git a/tests/gem_vmap_blits.c b/tests/gem_vmap_blits.c
index a6655a45..9c0a91ff 100644
--- a/tests/gem_vmap_blits.c
+++ b/tests/gem_vmap_blits.c
@@ -96,15 +96,7 @@ static uint32_t gem_vmap(int fd, void *ptr, int size, int read_only)
 
 static void gem_vmap_sync(int fd, uint32_t handle)
 {
-	struct drm_i915_gem_set_domain set_domain;
-	int ret;
-
-	set_domain.handle = handle;
-	set_domain.read_domains = I915_GEM_DOMAIN_CPU;
-	set_domain.write_domain = I915_GEM_DOMAIN_CPU;
-
-	ret = drmIoctl(fd, DRM_IOCTL_I915_GEM_SET_DOMAIN, &set_domain);
-	assert(ret == 0);
+	gem_set_domain(fd, handle, I915_GEM_DOMAIN_CPU, I915_GEM_DOMAIN_CPU);
 }
 
 static uint64_t