 @@ -1,14 +1,14 @@
-/*	$NetBSD: if_tap.c,v 1.114 2019/10/16 06:53:34 knakahara Exp $	*/
+/*	$NetBSD: if_tap.c,v 1.115 2020/01/06 20:31:35 christos Exp $	*/
 /*
  *  Copyright (c) 2003, 2004, 2008, 2009 The NetBSD Foundation.
  *  All rights reserved.
+ *
  *  Redistribution and use in source and binary forms, with or without
  *  modification, are permitted provided that the following conditions
  *  are met:
  *  1. Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
 @@ -23,27 +23,27 @@
  *  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  *  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  *  POSSIBILITY OF SUCH DAMAGE.
  */
 /*
  * tap(4) is a virtual Ethernet interface.  It appears as a real Ethernet
  * device to the system, but can also be accessed by userland through a
  * character device interface, which allows reading and injecting frames.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_tap.c,v 1.114 2019/10/16 06:53:34 knakahara Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_tap.c,v 1.115 2020/01/06 20:31:35 christos Exp $");
 #if defined(_KERNEL_OPT)
 #include "opt_modular.h"
 #endif
 #include <sys/param.h>
 #include <sys/atomic.h>
 #include <sys/conf.h>
 #include <sys/cprng.h>
 #include <sys/device.h>
 #include <sys/file.h>
 #include <sys/filedesc.h>
 @@ -515,26 +515,27 @@ tap_start(struct ifnet *ifp)
+{
 	struct tap_softc *sc = (struct tap_softc *)ifp->if_softc;
 	struct mbuf *m0;
 	mutex_enter(&sc->sc_lock);
 	if ((sc->sc_flags & TAP_INUSE) == 0) {
 		/* Simply drop packets */
 		for (;;) {
 			IFQ_DEQUEUE(&ifp->if_snd, m0);
 			if (m0 == NULL)
 				goto done;
 			ifp->if_opackets++;
 			ifp->if_obytes += m0->m_len;
 			bpf_mtap(ifp, m0, BPF_D_OUT);
 			m_freem(m0);
+		}
 	} else if (!IFQ_IS_EMPTY(&ifp->if_snd)) {
 		ifp->if_flags |= IFF_OACTIVE;
 		cv_broadcast(&sc->sc_cv);
 		selnotify(&sc->sc_rsel, 0, 1);
 		if (sc->sc_flags & TAP_ASYNCIO) {
 			kpreempt_disable();
 			softint_schedule(sc->sc_sih);
 			kpreempt_enable();
+		}
 @@ -883,26 +884,27 @@ tap_dev_close(struct tap_softc *sc)
 	ifp = &sc->sc_ec.ec_if;
 	ifp->if_flags &= ~IFF_OACTIVE;
 	/* Purge output queue */
 	if (!(IFQ_IS_EMPTY(&ifp->if_snd))) {
 		struct mbuf *m;
 		for (;;) {
 			IFQ_DEQUEUE(&ifp->if_snd, m);
 			if (m == NULL)
 				break;
 			ifp->if_opackets++;
 			ifp->if_obytes += m->m_len;
 			bpf_mtap(ifp, m, BPF_D_OUT);
 			m_freem(m);
+		}
+	}
 	splx(s);
 	if (sc->sc_sih != NULL) {
 		softint_disestablish(sc->sc_sih);
 		sc->sc_sih = NULL;
+	}
 	sc->sc_flags &= ~(TAP_INUSE | TAP_ASYNCIO);
 	return 0;
 @@ -969,27 +971,32 @@ tap_dev_read(int unit, struct uio *uio,
+		}
+	}
 	IFQ_DEQUEUE(&ifp->if_snd, m);
 	mutex_exit(&sc->sc_lock);
 	ifp->if_flags &= ~IFF_OACTIVE;
 	if (m == NULL) {
 		error = 0;
 		goto out;
+	}
 	ifp->if_opackets++;
 	ifp->if_obytes += m->m_len; // XXX: only first in chain
 	bpf_mtap(ifp, m, BPF_D_OUT);
 	if ((error = pfil_run_hooks(ifp->if_pfil, &m, ifp, PFIL_OUT)) != 0)
 		goto out;
 	if (m == NULL)
 		goto out;
 	/*
 	 * One read is one packet.
 	 */
 	do {
 		error = uiomove(mtod(m, void *),
 		    uimin(m->m_len, uio->uio_resid), uio);
 		m = n = m_free(m);
 	} while (m != NULL && uio->uio_resid > 0 && error == 0);
 	if (m != NULL)
 		m_freem(m);
 @@ -1040,63 +1047,73 @@ tap_fops_write(file_t *fp, off_t *offp,
 	KERNEL_LOCK(1, NULL);
 	error = tap_dev_write(fp->f_devunit, uio, flags);
 	KERNEL_UNLOCK_ONE(NULL);
 	return error;
+}
 static int
 tap_dev_write(int unit, struct uio *uio, int flags)
+{
 	struct tap_softc *sc =
 	    device_lookup_private(&tap_cd, unit);
 	struct ifnet *ifp;
 	struct mbuf *m, **mp;
 	size_t len = 0;
 	int error = 0;
 	if (sc == NULL)
 		return ENXIO;
 	getnanotime(&sc->sc_mtime);
 	ifp = &sc->sc_ec.ec_if;
 	/* One write, one packet, that's the rule */
 	MGETHDR(m, M_DONTWAIT, MT_DATA);
 	if (m == NULL) {
 		ifp->if_ierrors++;
 		return ENOBUFS;
+	}
 	m->m_pkthdr.len = uio->uio_resid;
 	mp = &m;
 	while (error == 0 && uio->uio_resid > 0) {
 		if (*mp != m) {
 			MGET(*mp, M_DONTWAIT, MT_DATA);
 			if (*mp == NULL) {
 				error = ENOBUFS;
 				break;
+			}
+		}
 		(*mp)->m_len = uimin(MHLEN, uio->uio_resid);
 		len += (*mp)->m_len;
 		error = uiomove(mtod(*mp, void *), (*mp)->m_len, uio);
 		mp = &(*mp)->m_next;
+	}
 	if (error) {
 		ifp->if_ierrors++;
 		m_freem(m);
 		return error;
+	}
 	m_set_rcvif(m, ifp);
 	ifp->if_ipackets++;
 	ifp->if_ibytes += len;
 	bpf_mtap(ifp, m, BPF_D_IN);
 	if ((error = pfil_run_hooks(ifp->if_pfil, &m, ifp, PFIL_IN)) != 0)
 		return error;
 	if (m == NULL)
 		return 0;
 	if_percpuq_enqueue(ifp->if_percpuq, m);
 	return 0;
+}
 static int
 tap_cdev_ioctl(dev_t dev, u_long cmd, void *data, int flags, struct lwp *l)
+{
 	return tap_dev_ioctl(minor(dev), cmd, data, l);
+}
 static int