commit 5efc5fb8dba9be0ec63437a20e2f6a082c08430c
Author: Ryota Ozaki <ozaki-r@iij.ad.jp>
Date:   Thu Nov 9 10:39:28 2017 +0900

    Unify IFEF_*_MPSAFE into IFEF_MPSAFE
    
    There are already two flags for if_output and if_start, however, it seems such
    MPSAFE flags are eventually needed for all if_XXX operations. Having discrete
    flags for each operation is wasteful of if_extflags bits. So let's unify
    the flags into one: IFEF_MPSAFE.
    
    Fortunately IFEF_*_MPSAFE flags have never been included in any releases, so
    we can change them without breaking backward compatibility of the releases
    (though the kernel version of -current should be bumped).
    
    Note that if an interface have both MP-safe and non-MP-safe operations at a
    time, we have to set the IFEF_MPSAFE flag and let callees of non-MP-safe
    opeartions take the kernel lock.

diff --git a/sys/arch/arm/sunxi/sunxi_emac.c b/sys/arch/arm/sunxi/sunxi_emac.c
index 8f5a63af768..b076e62b559 100644
--- a/sys/arch/arm/sunxi/sunxi_emac.c
+++ b/sys/arch/arm/sunxi/sunxi_emac.c
@@ -1381,7 +1381,7 @@ sunxi_emac_attach(device_t parent, device_t self, void *aux)
 	snprintf(ifp->if_xname, IFNAMSIZ, EMAC_IFNAME, device_unit(self));
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
 #ifdef EMAC_MPSAFE
-	ifp->if_extflags = IFEF_START_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 #endif
 	ifp->if_start = sunxi_emac_start;
 	ifp->if_ioctl = sunxi_emac_ioctl;
diff --git a/sys/dev/ic/dwc_gmac.c b/sys/dev/ic/dwc_gmac.c
index 285b97c2f25..4d7836b1276 100644
--- a/sys/dev/ic/dwc_gmac.c
+++ b/sys/dev/ic/dwc_gmac.c
@@ -223,7 +223,7 @@ dwc_gmac_attach(struct dwc_gmac_softc *sc, uint32_t mii_clk)
 	ifp->if_softc = sc;
 	strlcpy(ifp->if_xname, device_xname(sc->sc_dev), IFNAMSIZ);
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
-	ifp->if_extflags = IFEF_START_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 	ifp->if_ioctl = dwc_gmac_ioctl;
 	ifp->if_start = dwc_gmac_start;
 	ifp->if_init = dwc_gmac_init;
@@ -836,7 +836,7 @@ static void
 dwc_gmac_start(struct ifnet *ifp)
 {
 	struct dwc_gmac_softc *sc = ifp->if_softc;
-	KASSERT(ifp->if_extflags & IFEF_START_MPSAFE);
+	KASSERT(if_is_mpsafe(ifp));
 
 	mutex_enter(sc->sc_lock);
 	if (!sc->sc_stopping) {
diff --git a/sys/dev/pci/if_wm.c b/sys/dev/pci/if_wm.c
index 8bd163bc73e..b5ba23c44c8 100644
--- a/sys/dev/pci/if_wm.c
+++ b/sys/dev/pci/if_wm.c
@@ -2630,7 +2630,7 @@ alloc_retry:
 	ifp->if_softc = sc;
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
 #ifdef WM_MPSAFE
-	ifp->if_extflags = IFEF_START_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 #endif
 	ifp->if_ioctl = wm_ioctl;
 	if ((sc->sc_flags & WM_F_NEWQUEUE) != 0) {
@@ -6990,7 +6990,7 @@ wm_start(struct ifnet *ifp)
 	struct wm_txqueue *txq = &sc->sc_queue[0].wmq_txq;
 
 #ifdef WM_MPSAFE
-	KASSERT(ifp->if_extflags & IFEF_START_MPSAFE);
+	KASSERT(if_is_mpsafe(ifp));
 #endif
 	/*
 	 * ifp->if_obytes and ifp->if_omcasts are added in if_transmit()@if.c.
@@ -7583,7 +7583,7 @@ wm_nq_start(struct ifnet *ifp)
 	struct wm_txqueue *txq = &sc->sc_queue[0].wmq_txq;
 
 #ifdef WM_MPSAFE
-	KASSERT(ifp->if_extflags & IFEF_START_MPSAFE);
+	KASSERT(if_is_mpsafe(ifp));
 #endif
 	/*
 	 * ifp->if_obytes and ifp->if_omcasts are added in if_transmit()@if.c.
diff --git a/sys/dev/pci/ixgbe/ixgbe.c b/sys/dev/pci/ixgbe/ixgbe.c
index ef7e7868051..da8bb418e4b 100644
--- a/sys/dev/pci/ixgbe/ixgbe.c
+++ b/sys/dev/pci/ixgbe/ixgbe.c
@@ -1210,7 +1210,7 @@ ixgbe_setup_interface(device_t dev, struct adapter *adapter)
 	ifp->if_softc = adapter;
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
 #ifdef IXGBE_MPSAFE
-	ifp->if_extflags = IFEF_START_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 #endif
 	ifp->if_ioctl = ixgbe_ioctl;
 #if __FreeBSD_version >= 1100045
diff --git a/sys/dev/pci/ixgbe/ixv.c b/sys/dev/pci/ixgbe/ixv.c
index ef128a0d2a0..070561107e4 100644
--- a/sys/dev/pci/ixgbe/ixv.c
+++ b/sys/dev/pci/ixgbe/ixv.c
@@ -1391,7 +1391,7 @@ ixv_setup_interface(device_t dev, struct adapter *adapter)
 	ifp->if_softc = adapter;
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
 #ifdef IXGBE_MPSAFE
-	ifp->if_extflags = IFEF_START_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 #endif
 	ifp->if_ioctl = ixv_ioctl;
 	if (adapter->feat_en & IXGBE_FEATURE_LEGACY_TX) {
diff --git a/sys/net/if.h b/sys/net/if.h
index b341e0d13cf..c09303b76f2 100644
--- a/sys/net/if.h
+++ b/sys/net/if.h
@@ -387,16 +387,17 @@ typedef struct ifnet {
 #define	IFF_LINK2	0x4000		/* per link layer defined bit */
 #define	IFF_MULTICAST	0x8000		/* supports multicast */
 
-#define	IFEF_OUTPUT_MPSAFE		__BIT(0)	/* if_output() can run parallel */
-#define	IFEF_START_MPSAFE		__BIT(1)	/* if_start() can run parallel */
-#define	IFEF_NO_LINK_STATE_CHANGE	__BIT(2)	/* doesn't use link state interrupts */
+#define	IFEF_MPSAFE			__BIT(0)	/* handlers can run in parallel */
+#define	IFEF_NO_LINK_STATE_CHANGE	__BIT(1)	/* doesn't use link state interrupts */
 
 #ifdef _KERNEL
+#include <net/if_types.h>
+
 static inline bool
-if_output_is_mpsafe(struct ifnet *ifp)
+if_is_mpsafe(struct ifnet *ifp)
 {
 
-	return ((ifp->if_extflags & IFEF_OUTPUT_MPSAFE) != 0);
+	return ((ifp->if_extflags & IFEF_MPSAFE) != 0);
 }
 
 static inline int
@@ -404,7 +405,7 @@ if_output_lock(struct ifnet *cifp, struct ifnet *ifp, struct mbuf *m,
     const struct sockaddr *dst, const struct rtentry *rt)
 {
 
-	if (if_output_is_mpsafe(cifp)) {
+	if (if_is_mpsafe(cifp)) {
 		return (*cifp->if_output)(ifp, m, dst, rt);
 	} else {
 		int ret;
@@ -416,18 +417,11 @@ if_output_lock(struct ifnet *cifp, struct ifnet *ifp, struct mbuf *m,
 	}
 }
 
-static inline bool
-if_start_is_mpsafe(struct ifnet *ifp)
-{
-
-	return ((ifp->if_extflags & IFEF_START_MPSAFE) != 0);
-}
-
 static inline void
 if_start_lock(struct ifnet *ifp)
 {
 
-	if (if_start_is_mpsafe(ifp)) {
+	if (if_is_mpsafe(ifp)) {
 		(*ifp->if_start)(ifp);
 	} else {
 		KERNEL_LOCK(1, NULL);
diff --git a/sys/net/if_bridge.c b/sys/net/if_bridge.c
index ca6fa9ffe15..28c63ae501a 100644
--- a/sys/net/if_bridge.c
+++ b/sys/net/if_bridge.c
@@ -424,7 +424,7 @@ bridge_clone_create(struct if_clone *ifc, int unit)
 
 	if_initname(ifp, ifc->ifc_name, unit);
 	ifp->if_softc = sc;
-	ifp->if_extflags = IFEF_OUTPUT_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 	ifp->if_mtu = ETHERMTU;
 	ifp->if_ioctl = bridge_ioctl;
 	ifp->if_output = bridge_output;
@@ -1440,7 +1440,7 @@ bridge_output(struct ifnet *ifp, struct mbuf *m, const struct sockaddr *sa,
 	/*
 	 * bridge_output() is called from ether_output(), furthermore
 	 * ifp argument doesn't point to bridge(4). So, don't assert
-	 * IFEF_OUTPUT_MPSAFE here.
+	 * IFEF_MPSAFE here.
 	 */
 
 	if (m->m_len < ETHER_HDR_LEN) {
diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index f0fcae746ba..b99ce9c7d32 100644
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -204,13 +204,6 @@ ether_output(struct ifnet * const ifp0, struct mbuf * const m0,
 	struct at_ifaddr *aa;
 #endif /* NETATALK */
 
-	/*
-	 * some paths such as carp_output() call ethr_output() with "ifp"
-	 * argument as other than ether ifnet.
-	 */
-	KASSERT(ifp->if_output != ether_output
-	    || ifp->if_extflags & IFEF_OUTPUT_MPSAFE);
-
 #ifdef MBUFTRACE
 	m_claimm(m, ifp->if_mowner);
 #endif
@@ -951,7 +944,6 @@ ether_ifattach(struct ifnet *ifp, const uint8_t *lla)
 {
 	struct ethercom *ec = (struct ethercom *)ifp;
 
-	ifp->if_extflags |= IFEF_OUTPUT_MPSAFE;
 	ifp->if_type = IFT_ETHER;
 	ifp->if_hdrlen = ETHER_HDR_LEN;
 	ifp->if_dlt = DLT_EN10MB;
diff --git a/sys/net/if_gif.c b/sys/net/if_gif.c
index 13f74d59fac..03cd54395f5 100644
--- a/sys/net/if_gif.c
+++ b/sys/net/if_gif.c
@@ -275,7 +275,7 @@ gifattach0(struct gif_softc *sc)
 	sc->gif_if.if_flags  = IFF_POINTOPOINT | IFF_MULTICAST;
 	sc->gif_if.if_extflags  = IFEF_NO_LINK_STATE_CHANGE;
 #ifdef GIF_MPSAFE
-	sc->gif_if.if_extflags  |= IFEF_OUTPUT_MPSAFE;
+	sc->gif_if.if_extflags  |= IFEF_MPSAFE;
 #endif
 	sc->gif_if.if_ioctl  = gif_ioctl;
 	sc->gif_if.if_output = gif_output;
diff --git a/sys/net/if_l2tp.c b/sys/net/if_l2tp.c
index 19ccc692b0f..096d4bb443d 100644
--- a/sys/net/if_l2tp.c
+++ b/sys/net/if_l2tp.c
@@ -265,8 +265,7 @@ l2tpattach0(struct l2tp_softc *sc)
 	sc->l2tp_ec.ec_if.if_addrlen = 0;
 	sc->l2tp_ec.ec_if.if_mtu    = L2TP_MTU;
 	sc->l2tp_ec.ec_if.if_flags  = IFF_POINTOPOINT|IFF_MULTICAST|IFF_SIMPLEX;
-	sc->l2tp_ec.ec_if.if_extflags  = IFEF_OUTPUT_MPSAFE |
-	    IFEF_START_MPSAFE | IFEF_NO_LINK_STATE_CHANGE;
+	sc->l2tp_ec.ec_if.if_extflags  = IFEF_MPSAFE | IFEF_NO_LINK_STATE_CHANGE;
 	sc->l2tp_ec.ec_if.if_ioctl  = l2tp_ioctl;
 	sc->l2tp_ec.ec_if.if_output = l2tp_output;
 	sc->l2tp_ec.ec_if.if_type   = IFT_L2TP;
diff --git a/sys/net/if_loop.c b/sys/net/if_loop.c
index e1d2cb2d75b..91e2ded5ee3 100644
--- a/sys/net/if_loop.c
+++ b/sys/net/if_loop.c
@@ -183,7 +183,7 @@ loop_clone_create(struct if_clone *ifc, int unit)
 
 	ifp->if_mtu = LOMTU;
 	ifp->if_flags = IFF_LOOPBACK | IFF_MULTICAST | IFF_RUNNING;
-	ifp->if_extflags = IFEF_OUTPUT_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 	ifp->if_ioctl = loioctl;
 	ifp->if_output = looutput;
 #ifdef ALTQ
diff --git a/sys/net/if_pppoe.c b/sys/net/if_pppoe.c
index 71180fbf8e1..7d1cb68161a 100644
--- a/sys/net/if_pppoe.c
+++ b/sys/net/if_pppoe.c
@@ -303,7 +303,7 @@ pppoe_clone_create(struct if_clone *ifc, int unit)
 	sc->sc_sppp.pp_if.if_mtu = PPPOE_MAXMTU;
 	sc->sc_sppp.pp_if.if_flags = IFF_SIMPLEX|IFF_POINTOPOINT|IFF_MULTICAST;
 #ifdef PPPOE_MPSAFE
-	sc->sc_sppp.pp_if.if_extflags = IFEF_OUTPUT_MPSAFE;
+	sc->sc_sppp.pp_if.if_extflags = IFEF_MPSAFE;
 #endif
 	sc->sc_sppp.pp_if.if_type = IFT_PPP;
 	sc->sc_sppp.pp_if.if_hdrlen = sizeof(struct ether_header) + PPPOE_HEADERLEN;
diff --git a/sys/net/if_vlan.c b/sys/net/if_vlan.c
index 9816a4d6ac1..b69bd1b4370 100644
--- a/sys/net/if_vlan.c
+++ b/sys/net/if_vlan.c
@@ -338,7 +338,7 @@ vlan_clone_create(struct if_clone *ifc, int unit)
 	if_initname(ifp, ifc->ifc_name, unit);
 	ifp->if_softc = ifv;
 	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
-	ifp->if_extflags = IFEF_START_MPSAFE | IFEF_NO_LINK_STATE_CHANGE;
+	ifp->if_extflags = IFEF_MPSAFE | IFEF_NO_LINK_STATE_CHANGE;
 	ifp->if_start = vlan_start;
 	ifp->if_transmit = vlan_transmit;
 	ifp->if_ioctl = vlan_ioctl;
diff --git a/sys/netcan/if_canloop.c b/sys/netcan/if_canloop.c
index 2fd367ff0c8..afe23647715 100644
--- a/sys/netcan/if_canloop.c
+++ b/sys/netcan/if_canloop.c
@@ -112,7 +112,7 @@ canloop_clone_create(struct if_clone *ifc, int unit)
 	if_initname(ifp, ifc->ifc_name, unit);
 
 	ifp->if_flags = IFF_LOOPBACK | IFF_RUNNING;
-	ifp->if_extflags = IFEF_OUTPUT_MPSAFE;
+	ifp->if_extflags = IFEF_MPSAFE;
 	ifp->if_ioctl = canloop_ioctl;
 	ifp->if_start = canloop_ifstart;
 	can_ifattach(ifp);
diff --git a/sys/netinet/ip_carp.c b/sys/netinet/ip_carp.c
index 21fd499ab31..feb2f94d727 100644
--- a/sys/netinet/ip_carp.c
+++ b/sys/netinet/ip_carp.c
@@ -880,7 +880,6 @@ carp_clone_create(struct if_clone *ifc, int unit)
 	/* Overwrite ethernet defaults */
 	ifp->if_type = IFT_CARP;
 	ifp->if_output = carp_output;
-	ifp->if_extflags &= ~IFEF_OUTPUT_MPSAFE;
 	if_register(ifp);
 
 	return (0);