block: Really pause block jobs on drain

We already requested that block jobs be paused in .bdrv_drained_begin,
but no guarantee was made that the job was actually inactive at the
point where bdrv_drained_begin() returned.

This introduces a new callback BdrvChildRole.bdrv_drained_poll() and
uses it to make bdrv_drain_poll() consider block jobs using the node to
be drained.

For the test case to work as expected, we have to switch from
block_job_sleep_ns() to qemu_co_sleep_ns() so that the test job is even
considered active and must be waited for when draining the node.

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

1 files changed, 9 insertions, 0 deletions

diff --git a/block.c b/block.c
index afe30caac3..8cf9cd8855 100644
--- a/block.c
+++ b/block.c
@@ -821,6 +821,12 @@ static void bdrv_child_cb_drained_begin(BdrvChild *child)
     bdrv_drained_begin(bs);
 }
 
+static bool bdrv_child_cb_drained_poll(BdrvChild *child)
+{
+    BlockDriverState *bs = child->opaque;
+    return bdrv_drain_poll(bs, NULL);
+}
+
 static void bdrv_child_cb_drained_end(BdrvChild *child)
 {
     BlockDriverState *bs = child->opaque;
@@ -905,6 +911,7 @@ const BdrvChildRole child_file = {
     .get_parent_desc = bdrv_child_get_parent_desc,
     .inherit_options = bdrv_inherited_options,
     .drained_begin   = bdrv_child_cb_drained_begin,
+    .drained_poll    = bdrv_child_cb_drained_poll,
     .drained_end     = bdrv_child_cb_drained_end,
     .attach          = bdrv_child_cb_attach,
     .detach          = bdrv_child_cb_detach,
@@ -929,6 +936,7 @@ const BdrvChildRole child_format = {
     .get_parent_desc = bdrv_child_get_parent_desc,
     .inherit_options = bdrv_inherited_fmt_options,
     .drained_begin   = bdrv_child_cb_drained_begin,
+    .drained_poll    = bdrv_child_cb_drained_poll,
     .drained_end     = bdrv_child_cb_drained_end,
     .attach          = bdrv_child_cb_attach,
     .detach          = bdrv_child_cb_detach,
@@ -1048,6 +1056,7 @@ const BdrvChildRole child_backing = {
     .detach          = bdrv_backing_detach,
     .inherit_options = bdrv_backing_options,
     .drained_begin   = bdrv_child_cb_drained_begin,
+    .drained_poll    = bdrv_child_cb_drained_poll,
     .drained_end     = bdrv_child_cb_drained_end,
     .inactivate      = bdrv_child_cb_inactivate,
     .update_filename = bdrv_backing_update_filename,