mirror: add buf-size argument to drive-mirror

This makes sense when the next commit starts using the extra buffer space
to perform many I/O operations asynchronously.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

2 files changed, 33 insertions, 2 deletions

diff --git a/tests/qemu-iotests/041 b/tests/qemu-iotests/041
index a1299b348e..b040820c51 100755
--- a/tests/qemu-iotests/041
+++ b/tests/qemu-iotests/041
@@ -207,6 +207,37 @@ class TestSingleDrive(ImageMirroringTestCase):
         self.assertTrue(self.compare_images(test_img, target_img),
                         'target image does not match source after mirroring')
 
+    def test_small_buffer(self):
+        self.assert_no_active_mirrors()
+
+        # A small buffer is rounded up automatically
+        result = self.vm.qmp('drive-mirror', device='drive0', sync='full',
+                             buf_size=4096, target=target_img)
+        self.assert_qmp(result, 'return', {})
+
+        self.complete_and_wait()
+        result = self.vm.qmp('query-block')
+        self.assert_qmp(result, 'return[0]/inserted/file', target_img)
+        self.vm.shutdown()
+        self.assertTrue(self.compare_images(test_img, target_img),
+                        'target image does not match source after mirroring')
+
+    def test_small_buffer2(self):
+        self.assert_no_active_mirrors()
+
+        qemu_img('create', '-f', iotests.imgfmt, '-o', 'cluster_size=%d,size=%d'
+                        % (TestSingleDrive.image_len, TestSingleDrive.image_len), target_img)
+        result = self.vm.qmp('drive-mirror', device='drive0', sync='full',
+                             buf_size=65536, mode='existing', target=target_img)
+        self.assert_qmp(result, 'return', {})
+
+        self.complete_and_wait()
+        result = self.vm.qmp('query-block')
+        self.assert_qmp(result, 'return[0]/inserted/file', target_img)
+        self.vm.shutdown()
+        self.assertTrue(self.compare_images(test_img, target_img),
+                        'target image does not match source after mirroring')
+
     def test_large_cluster(self):
         self.assert_no_active_mirrors()
 
diff --git a/tests/qemu-iotests/041.out b/tests/qemu-iotests/041.out
index 3a89159833..84bfd63fba 100644
--- a/tests/qemu-iotests/041.out
+++ b/tests/qemu-iotests/041.out
@@ -1,5 +1,5 @@
-....................
+......................
 ----------------------------------------------------------------------
-Ran 20 tests
+Ran 22 tests
 
 OK