block: Mark bdrv_co_block_status() and callers GRAPH_RDLOCK

This adds GRAPH_RDLOCK annotations to declare that callers of
bdrv_co_block_status() need to hold a reader lock for the graph.

For some places, we know that they will hold the lock, but we don't have
the GRAPH_RDLOCK annotations yet. In this case, add assume_graph_lock()
with a FIXME comment. These places will be removed once everything is
properly annotated.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-5-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
diff --git a/qemu-img.c b/qemu-img.c
index 7c05931..cd0178b 100644
--- a/qemu-img.c
+++ b/qemu-img.c
@@ -1991,7 +1991,9 @@
             qemu_co_mutex_unlock(&s->lock);
             break;
         }
-        n = convert_iteration_sectors(s, s->sector_num);
+        WITH_GRAPH_RDLOCK_GUARD() {
+            n = convert_iteration_sectors(s, s->sector_num);
+        }
         if (n < 0) {
             qemu_co_mutex_unlock(&s->lock);
             s->ret = n;