r222225: "Recognize BIO_FLUSH requests and pass them to userland."

diff --git a/sys/geom/gate/g_gate.c b/sys/geom/gate/g_gate.c
index 9b4d782..22338a5 100644
--- a/sys/geom/gate/g_gate.c
+++ b/sys/geom/gate/g_gate.c
@@ -180,6 +180,7 @@ g_gate_start(struct bio *bp)
                break;
        case BIO_DELETE:
        case BIO_WRITE:
+       case BIO_FLUSH:
[...]