[src/trunk]: src/sys/dev/pci Take TX/RX locks when sc_stopping = true in if_stop

[ozaki-r <ozaki-r%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/57e923216cd6
branches:  trunk
changeset: 805218:57e923216cd6
user:      ozaki-r <ozaki-r%NetBSD.org@localhost>
date:      Wed Dec 24 02:48:24 2014 +0000

description:
Take TX/RX locks when sc_stopping = true in if_stop

Taking the locks is needed to ensure ongoing TX/RX operations finish.
Otherwise, if_stop may run during TX/RX operations.

diffstat:

 sys/dev/pci/if_vioif.c |  9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diffs (31 lines):

diff -r 5fab1bb6d7ec -r 57e923216cd6 sys/dev/pci/if_vioif.c
--- a/sys/dev/pci/if_vioif.c    Wed Dec 24 00:36:09 2014 +0000
+++ b/sys/dev/pci/if_vioif.c    Wed Dec 24 02:48:24 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_vioif.c,v 1.12 2014/12/19 06:54:40 ozaki-r Exp $    */
+/*     $NetBSD: if_vioif.c,v 1.13 2014/12/24 02:48:24 ozaki-r Exp $    */
 
 /*
  * Copyright (c) 2010 Minoura Makoto.
@@ -26,7 +26,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_vioif.c,v 1.12 2014/12/19 06:54:40 ozaki-r Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_vioif.c,v 1.13 2014/12/24 02:48:24 ozaki-r Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -707,7 +707,12 @@
        struct vioif_softc *sc = ifp->if_softc;
        struct virtio_softc *vsc = sc->sc_virtio;
 
+       /* Take the locks to ensure that ongoing TX/RX finish */
+       VIOIF_TX_LOCK(sc);
+       VIOIF_RX_LOCK(sc);
        sc->sc_stopping = true;
+       VIOIF_RX_UNLOCK(sc);
+       VIOIF_TX_UNLOCK(sc);
 
        /* only way to stop I/O and DMA is resetting... */
        virtio_reset(vsc);