From 7a587bf1f9cac772532a41e31202fd7ef8646928 Mon Sep 17 00:00:00 2001

From: Kevin Wolf <kwolf@redhat.com>

Date: Fri, 14 Sep 2018 10:55:09 +0200

Subject: [PATCH 18/49] test-bdrv-drain: Test node deletion in subtree

 recursion

RH-Author: Kevin Wolf <kwolf@redhat.com>

Message-id: <20180914105540.18077-12-kwolf@redhat.com>

Patchwork-id: 82159

O-Subject: [RHV-7.6 qemu-kvm-rhev PATCH 11/42] test-bdrv-drain: Test node deletion in subtree recursion

Bugzilla: 1601212

RH-Acked-by: John Snow <jsnow@redhat.com>

RH-Acked-by: Max Reitz <mreitz@redhat.com>

RH-Acked-by: Fam Zheng <famz@redhat.com>

If bdrv_do_drained_begin() polls during its subtree recursion, the graph

can change and mess up the bs->children iteration. Test that this

doesn't happen.

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

(cherry picked from commit ebd31837618cdc7bda83090773dcdd87475d55b7)

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

Signed-off-by: Miroslav Rezanina <mrezanin@redhat.com>

---

 tests/test-bdrv-drain.c | 38 +++++++++++++++++++++++++++++---------

 1 file changed, 29 insertions(+), 9 deletions(-)

diff --git a/tests/test-bdrv-drain.c b/tests/test-bdrv-drain.c

index 8918a94..38706b0 100644

--- a/tests/test-bdrv-drain.c

+++ b/tests/test-bdrv-drain.c

@@ -875,7 +875,8 @@ static void coroutine_fn test_co_delete_by_drain(void *opaque)

  * If @detach_instead_of_delete is set, the BDS is not going to be

  * deleted but will only detach all of its children.

  */

-static void do_test_delete_by_drain(bool detach_instead_of_delete)

+static void do_test_delete_by_drain(bool detach_instead_of_delete,

+                                    enum drain_type drain_type)

 {

     BlockBackend *blk;

     BlockDriverState *bs, *child_bs, *null_bs;

@@ -931,9 +932,23 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete)

      * test_co_delete_by_drain() resuming.  Thus, @bs will be deleted

      * and the coroutine will exit while this drain operation is still

      * in progress. */

-    bdrv_ref(child_bs);

-    bdrv_drain(child_bs);

-    bdrv_unref(child_bs);

+    switch (drain_type) {

+    case BDRV_DRAIN:

+        bdrv_ref(child_bs);

+        bdrv_drain(child_bs);

+        bdrv_unref(child_bs);

+        break;

+    case BDRV_SUBTREE_DRAIN:

+        /* Would have to ref/unref bs here for !detach_instead_of_delete, but

+         * then the whole test becomes pointless because the graph changes

+         * don't occur during the drain any more. */

+        assert(detach_instead_of_delete);

+        bdrv_subtree_drained_begin(bs);

+        bdrv_subtree_drained_end(bs);

+        break;

+    default:

+        g_assert_not_reached();

+    }

     while (!dbdd.done) {

         aio_poll(qemu_get_aio_context(), true);

@@ -946,15 +961,19 @@ static void do_test_delete_by_drain(bool detach_instead_of_delete)

     }

 }

-

 static void test_delete_by_drain(void)

 {

-    do_test_delete_by_drain(false);

+    do_test_delete_by_drain(false, BDRV_DRAIN);

 }

 static void test_detach_by_drain(void)

 {

-    do_test_delete_by_drain(true);

+    do_test_delete_by_drain(true, BDRV_DRAIN);

+}

+

+static void test_detach_by_drain_subtree(void)

+{

+    do_test_delete_by_drain(true, BDRV_SUBTREE_DRAIN);

 }

@@ -1005,8 +1024,9 @@ int main(int argc, char **argv)

     g_test_add_func("/bdrv-drain/blockjob/drain_subtree",

                     test_blockjob_drain_subtree);

-    g_test_add_func("/bdrv-drain/deletion", test_delete_by_drain);

-    g_test_add_func("/bdrv-drain/detach", test_detach_by_drain);

+    g_test_add_func("/bdrv-drain/deletion/drain", test_delete_by_drain);

+    g_test_add_func("/bdrv-drain/detach/drain", test_detach_by_drain);

+    g_test_add_func("/bdrv-drain/detach/drain_subtree", test_detach_by_drain_subtree);

     ret = g_test_run();

     qemu_event_destroy(&done_event);

-- 

1.8.3.1