[RFC PATCH] test-bdrv-drain: keep graph manipulations out of coroutines

[Paolo Bonzini <pbonzini@redhat.com>]

Changes to the BlockDriverState graph will have to take the
corresponding lock for writing, and therefore cannot be done
inside a coroutine.  Move them outside the test body.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 tests/unit/test-bdrv-drain.c | 63 ++++++++++++++++++++++++++----------
 1 file changed, 46 insertions(+), 17 deletions(-)

diff --git a/tests/unit/test-bdrv-drain.c b/tests/unit/test-bdrv-drain.c
index 6ae44116fe79..d85083dd4f9e 100644
--- a/tests/unit/test-bdrv-drain.c
+++ b/tests/unit/test-bdrv-drain.c
@@ -199,25 +199,40 @@ static void do_drain_end_unlocked(enum drain_type drain_type, BlockDriverState *
     }
 }
 
+static BlockBackend *blk;
+static BlockDriverState *bs, *backing;
+
+static void test_drv_cb_init(void)
+{
+    blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
+    bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
+                              &error_abort);
+    blk_insert_bs(blk, bs, &error_abort);
+
+    backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
+    bdrv_set_backing_hd(bs, backing, &error_abort);
+}
+
+static void test_drv_cb_fini(void)
+{
+    bdrv_unref(backing);
+    bdrv_unref(bs);
+    blk_unref(blk);
+    backing = NULL;
+    bs = NULL;
+    blk = NULL;
+}
+
 static void test_drv_cb_common(enum drain_type drain_type, bool recursive)
 {
-    BlockBackend *blk;
-    BlockDriverState *bs, *backing;
     BDRVTestState *s, *backing_s;
     BlockAIOCB *acb;
     int aio_ret;
 
     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, NULL, 0);
 
-    blk = blk_new(qemu_get_aio_context(), BLK_PERM_ALL, BLK_PERM_ALL);
-    bs = bdrv_new_open_driver(&bdrv_test, "test-node", BDRV_O_RDWR,
-                              &error_abort);
     s = bs->opaque;
-    blk_insert_bs(blk, bs, &error_abort);
-
-    backing = bdrv_new_open_driver(&bdrv_test, "backing", 0, &error_abort);
     backing_s = backing->opaque;
-    bdrv_set_backing_hd(bs, backing, &error_abort);
 
     /* Simple bdrv_drain_all_begin/end pair, check that CBs are called */
     g_assert_cmpint(s->drain_count, ==, 0);
@@ -252,30 +267,44 @@ static void test_drv_cb_common(enum drain_type drain_type, bool recursive)
 
     g_assert_cmpint(s->drain_count, ==, 0);
     g_assert_cmpint(backing_s->drain_count, ==, 0);
-
-    bdrv_unref(backing);
-    bdrv_unref(bs);
-    blk_unref(blk);
 }
 
-static void test_drv_cb_drain_all(void)
+static void test_drv_cb_do_drain_all(void)
 {
     test_drv_cb_common(BDRV_DRAIN_ALL, true);
 }
 
-static void test_drv_cb_drain(void)
+static void test_drv_cb_do_drain(void)
 {
     test_drv_cb_common(BDRV_DRAIN, false);
 }
 
+static void test_drv_cb_drain_all(void)
+{
+    test_drv_cb_init();
+    test_drv_cb_do_drain_all();
+    test_drv_cb_fini();
+}
+
+static void test_drv_cb_drain(void)
+{
+    test_drv_cb_init();
+    test_drv_cb_do_drain();
+    test_drv_cb_fini();
+}
+
 static void test_drv_cb_co_drain_all(void)
 {
-    call_in_coroutine(test_drv_cb_drain_all);
+    test_drv_cb_init();
+    call_in_coroutine(test_drv_cb_do_drain_all);
+    test_drv_cb_fini();
 }
 
 static void test_drv_cb_co_drain(void)
 {
-    call_in_coroutine(test_drv_cb_drain);
+    test_drv_cb_init();
+    call_in_coroutine(test_drv_cb_do_drain);
+    test_drv_cb_fini();
 }
 
 static void test_quiesce_common(enum drain_type drain_type, bool recursive)
-- 
2.38.1