-----BEGIN PGP SIGNATURE-----

Version: GnuPG v1
 
 iQIcBAABAgAGBQJW+dDJAAoJEL2+eyfA3jBXk6oP/R/zX4foUVFMTvDbxHwWc41t
 gXGk1BpIjFnteab/tzUBDIdgs/DPxzM6bClhe45gNInVBgnOyeVmpUwRGGNYQKbn
 FdkrAcC6Vy6BJv+xRTMMS+h4i6ebJ6HqqQPwkz0VulxsAknDPQsBebe0tM8uO7k9
 G+ccMYOyUUiGTIRC3pBkRCu8APEialPSv3MpUTMtp71R3US+pEwmo1AgyOFq/lDu
 B/8LUBoR48XCEGfOA6ZixzoMwF1lTWpezx5/KF+fQ26sgnNzjpwYWnJk+LG7Gtvj
 8PHYsHDoXSISlIgxzLpS0AA6s54+mutgIeNJG5FBXGrSSNlAB1+cKZsnZw42YjfI
 BVIHQkmcGT+h9UEDdekiOfQorypSYRm51ueTGO/lUbxNifvJ5LQA97F0G/filoCj
 ovGIfOwgpWaEBPCb//U1TRGhhTg+dNyCeC4GoxDEFyWmLPYp8p7Xtz+vsZOIdH4O
 Wl9i6BzzeNEgJyutKqn2qpNLl6Pfd548MOJJqAUkGxDGrCJMkmn2lJSpSSji6cdm
 y4Az/tPY0/xpxwjSRakaIMOlhDoGXmrQG+I6JG1TZLSH7x1+Ajhr2ryx4CBONceV
 1quibAqoG1GwxCyYn7dv4aeJrDlg3XzEWQW6nJhuE91d9ZH+jF5u2+i+IZcQCDBe
 Cd6d0SZlcOnq3M5LiOrA
 =1ekF
 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/cody/tags/block-pull-request' into staging

# gpg: Signature made Tue 29 Mar 2016 01:48:09 BST using RSA key ID C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"

* remotes/cody/tags/block-pull-request:
  qemu-iotests: add no-op streaming test
  qemu-iotests: fix test_stream_partial()
  block: never cancel a streaming job without running stream_complete()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

block/stream.c

@@ -90,21 +90,21 @@ static void coroutine_fn stream_run(void *opaque)
     StreamCompleteData *data;
     BlockDriverState *bs = s->common.bs;
     BlockDriverState *base = s->base;
-    int64_t sector_num, end;
+    int64_t sector_num = 0;
+    int64_t end = -1;
     int error = 0;
     int ret = 0;
     int n = 0;
     void *buf;
 
     if (!bs->backing) {
-        block_job_completed(&s->common, 0);
+        goto out;
-        return;
     }
 
     s->common.len = bdrv_getlength(bs);
     if (s->common.len < 0) {
-        block_job_completed(&s->common, s->common.len);
+        ret = s->common.len;
-        return;
+        goto out;
     }
 
     end = s->common.len >> BDRV_SECTOR_BITS;
@@ -191,6 +191,7 @@ wait:
 
     qemu_vfree(buf);
 
+out:
     /* Modify backing chain and close BDSes in main loop */
     data = g_malloc(sizeof(*data));
     data->ret = ret;

tests/qemu-iotests/030

@@ -35,6 +35,7 @@ class TestSingleDrive(iotests.QMPTestCase):
         qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % backing_img, mid_img)
         qemu_img('create', '-f', iotests.imgfmt, '-o', 'backing_file=%s' % mid_img, test_img)
         qemu_io('-f', 'raw', '-c', 'write -P 0x1 0 512', backing_img)
+        qemu_io('-f', iotests.imgfmt, '-c', 'write -P 0x1 524288 512', mid_img)
         self.vm = iotests.VM().add_drive("blkdebug::" + test_img)
         self.vm.launch()
 
@@ -90,10 +91,28 @@ class TestSingleDrive(iotests.QMPTestCase):
                          qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img),
                          'image file map does not match backing file after streaming')
 
+    def test_stream_no_op(self):
+        self.assert_no_active_block_jobs()
+
+        # The image map is empty before the operation
+        empty_map = qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img)
+
+        # This is a no-op: no data should ever be copied from the base image
+        result = self.vm.qmp('block-stream', device='drive0', base=mid_img)
+        self.assert_qmp(result, 'return', {})
+
+        self.wait_until_completed()
+
+        self.assert_no_active_block_jobs()
+        self.vm.shutdown()
+
+        self.assertEqual(qemu_io('-f', iotests.imgfmt, '-c', 'map', test_img),
+                         empty_map, 'image file map changed after a no-op')
+
     def test_stream_partial(self):
         self.assert_no_active_block_jobs()
 
-        result = self.vm.qmp('block-stream', device='drive0', base=mid_img)
+        result = self.vm.qmp('block-stream', device='drive0', base=backing_img)
         self.assert_qmp(result, 'return', {})
 
         self.wait_until_completed()

tests/qemu-iotests/030.out

@@ -1,5 +1,5 @@
-.............
+..............
 ----------------------------------------------------------------------
-Ran 13 tests
+Ran 14 tests
 
 OK