Move Rx/Tx lists management routines into central location.

16 files changed, 462 insertions, 1040 deletions

diff --git a/sys/dev/usb/if_aue.c b/sys/dev/usb/if_aue.c
index 738dfbf..515f2bc 100644
--- a/sys/dev/usb/if_aue.c
+++ b/sys/dev/usb/if_aue.c
@@ -181,8 +181,6 @@ Static int aue_attach(device_ptr_t);
 Static int aue_detach(device_ptr_t);
 
 Static void aue_reset_pegasus_II(struct aue_softc *sc);
-Static int aue_tx_list_init(struct aue_softc *);
-Static int aue_rx_list_init(struct aue_softc *);
 Static int aue_encap(struct aue_softc *, struct mbuf *, int);
 #ifdef AUE_INTR_PIPE
 Static void aue_intr(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -803,57 +801,6 @@ aue_detach(device_ptr_t dev)
 	return (0);
 }
 
-Static int
-aue_rx_list_init(struct aue_softc *sc)
-{
-	struct aue_cdata	*cd;
-	struct aue_chain	*c;
-	int			i;
-
-	cd = &sc->aue_cdata;
-	for (i = 0; i < AUE_RX_LIST_CNT; i++) {
-		c = &cd->aue_rx_chain[i];
-		c->aue_sc = sc;
-		c->aue_idx = i;
-		c->aue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->aue_dev));
-		if (c->aue_mbuf == NULL)
-			return (ENOBUFS);
-		if (c->aue_xfer == NULL) {
-			c->aue_xfer = usbd_alloc_xfer(sc->aue_udev);
-			if (c->aue_xfer == NULL)
-				return (ENOBUFS);
-		}
-	}
-
-	return (0);
-}
-
-Static int
-aue_tx_list_init(struct aue_softc *sc)
-{
-	struct aue_cdata	*cd;
-	struct aue_chain	*c;
-	int			i;
-
-	cd = &sc->aue_cdata;
-	for (i = 0; i < AUE_TX_LIST_CNT; i++) {
-		c = &cd->aue_tx_chain[i];
-		c->aue_sc = sc;
-		c->aue_idx = i;
-		c->aue_mbuf = NULL;
-		if (c->aue_xfer == NULL) {
-			c->aue_xfer = usbd_alloc_xfer(sc->aue_udev);
-			if (c->aue_xfer == NULL)
-				return (ENOBUFS);
-		}
-		c->aue_buf = malloc(AUE_BUFSZ, M_USBDEV, M_NOWAIT);
-		if (c->aue_buf == NULL)
-			return (ENOBUFS);
-	}
-
-	return (0);
-}
-
 #ifdef AUE_INTR_PIPE
 Static void
 aue_intr(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
@@ -900,24 +847,26 @@ Static void
 aue_rxstart(struct ifnet *ifp)
 {
 	struct aue_softc	*sc;
-	struct aue_chain	*c;
+	struct ue_chain	*c;
 
 	sc = ifp->if_softc;
 	AUE_LOCK(sc);
-	c = &sc->aue_cdata.aue_rx_chain[sc->aue_cdata.aue_rx_prod];
+	c = &sc->aue_cdata.ue_rx_chain[sc->aue_cdata.ue_rx_prod];
 
-	c->aue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->aue_dev));
-	if (c->aue_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->aue_dev));
 		ifp->if_ierrors++;
 		AUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->aue_xfer, sc->aue_ep[AUE_ENDPT_RX],
-	    c, mtod(c->aue_mbuf, char *), AUE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->aue_ep[AUE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, aue_rxeof);
-	usbd_transfer(c->aue_xfer);
+	usbd_transfer(c->ue_xfer);
 
 	AUE_UNLOCK(sc);
 	return;
@@ -930,8 +879,8 @@ aue_rxstart(struct ifnet *ifp)
 Static void
 aue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct aue_chain	*c = priv;
-	struct aue_softc	*sc = c->aue_sc;
+	struct ue_chain	*c = priv;
+	struct aue_softc	*sc = c->ue_sc;
         struct mbuf		*m;
         struct ifnet		*ifp;
 	int			total_len = 0;
@@ -967,7 +916,7 @@ aue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 		goto done;
 	}
 
-	m = c->aue_mbuf;
+	m = c->ue_mbuf;
 	bcopy(mtod(m, char *) + total_len - 4, (char *)&r, sizeof(r));
 
 	/* Turn off all the non-error bits in the rx status word. */
@@ -993,7 +942,7 @@ done:
 
 	/* Setup new transfer. */
 	usbd_setup_xfer(xfer, sc->aue_ep[AUE_ENDPT_RX],
-	    c, mtod(c->aue_mbuf, char *), AUE_BUFSZ, USBD_SHORT_XFER_OK,
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, aue_rxeof);
 	usbd_transfer(xfer);
 
@@ -1009,8 +958,8 @@ done:
 Static void
 aue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct aue_chain	*c = priv;
-	struct aue_softc	*sc = c->aue_sc;
+	struct ue_chain	*c = priv;
+	struct aue_softc	*sc = c->ue_sc;
 	struct ifnet		*ifp;
 	usbd_status		err;
 
@@ -1032,12 +981,12 @@ aue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	ifp->if_timer = 0;
 	ifp->if_flags &= ~IFF_OACTIVE;
-	usbd_get_xfer_status(c->aue_xfer, NULL, NULL, NULL, &err);
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &err);
 
-	if (c->aue_mbuf != NULL) {
-		c->aue_mbuf->m_pkthdr.rcvif = ifp;
-		usb_tx_done(c->aue_mbuf);
-		c->aue_mbuf = NULL;
+	if (c->ue_mbuf != NULL) {
+		c->ue_mbuf->m_pkthdr.rcvif = ifp;
+		usb_tx_done(c->ue_mbuf);
+		c->ue_mbuf = NULL;
 	}
 
 	if (err)
@@ -1088,17 +1037,17 @@ Static int
 aue_encap(struct aue_softc *sc, struct mbuf *m, int idx)
 {
 	int			total_len;
-	struct aue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 
-	c = &sc->aue_cdata.aue_tx_chain[idx];
+	c = &sc->aue_cdata.ue_tx_chain[idx];
 
 	/*
 	 * Copy the mbuf data into a contiguous buffer, leaving two
 	 * bytes at the beginning to hold the frame length.
 	 */
-	m_copydata(m, 0, m->m_pkthdr.len, c->aue_buf + 2);
-	c->aue_mbuf = m;
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf + 2);
+	c->ue_mbuf = m;
 
 	total_len = m->m_pkthdr.len + 2;
 
@@ -1108,21 +1057,21 @@ aue_encap(struct aue_softc *sc, struct mbuf *m, int idx)
 	 * transfer, however it actually seems to ignore this info
 	 * and base the frame size on the bulk transfer length.
 	 */
-	c->aue_buf[0] = (u_int8_t)m->m_pkthdr.len;
-	c->aue_buf[1] = (u_int8_t)(m->m_pkthdr.len >> 8);
+	c->ue_buf[0] = (u_int8_t)m->m_pkthdr.len;
+	c->ue_buf[1] = (u_int8_t)(m->m_pkthdr.len >> 8);
 
-	usbd_setup_xfer(c->aue_xfer, sc->aue_ep[AUE_ENDPT_TX],
-	    c, c->aue_buf, total_len, USBD_FORCE_SHORT_XFER,
+	usbd_setup_xfer(c->ue_xfer, sc->aue_ep[AUE_ENDPT_TX],
+	    c, c->ue_buf, total_len, USBD_FORCE_SHORT_XFER,
 	    10000, aue_txeof);
 
 	/* Transmit */
-	err = usbd_transfer(c->aue_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (err != USBD_IN_PROGRESS) {
 		aue_stop(sc);
 		return (EIO);
 	}
 
-	sc->aue_cdata.aue_tx_cnt++;
+	sc->aue_cdata.ue_tx_cnt++;
 
 	return (0);
 }
@@ -1181,7 +1130,7 @@ aue_init(void *xsc)
 	struct aue_softc	*sc = xsc;
 	struct ifnet		*ifp = &sc->arpcom.ac_if;
 	struct mii_data		*mii = GET_MII(sc);
-	struct aue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 	int			i;
 
@@ -1208,21 +1157,23 @@ aue_init(void *xsc)
 		AUE_CLRBIT(sc, AUE_CTL2, AUE_CTL2_RX_PROMISC);
 
 	/* Init TX ring. */
-	if (aue_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->aue_cdata,
+	    USBDEVNAME(sc->aue_dev), sc->aue_udev) == ENOBUFS) {
 		printf("aue%d: tx list init failed\n", sc->aue_unit);
 		AUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Init RX ring. */
-	if (aue_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->aue_cdata,
+	    USBDEVNAME(sc->aue_dev), sc->aue_udev) == ENOBUFS) {
 		printf("aue%d: rx list init failed\n", sc->aue_unit);
 		AUE_UNLOCK(sc);
 		return;
 	}
 
 #ifdef AUE_INTR_PIPE
-	sc->aue_cdata.aue_ibuf = malloc(AUE_INTR_PKTLEN, M_USBDEV, M_NOWAIT);
+	sc->aue_cdata.ue_ibuf = malloc(AUE_INTR_PKTLEN, M_USBDEV, M_NOWAIT);
 #endif
 
 	/* Load the multicast filter. */
@@ -1256,7 +1207,7 @@ aue_init(void *xsc)
 #ifdef AUE_INTR_PIPE
 	err = usbd_open_pipe_intr(sc->aue_iface, sc->aue_ed[AUE_ENDPT_INTR],
 	    USBD_SHORT_XFER_OK, &sc->aue_ep[AUE_ENDPT_INTR], sc,
-	    sc->aue_cdata.aue_ibuf, AUE_INTR_PKTLEN, aue_intr,
+	    sc->aue_cdata.ue_ibuf, AUE_INTR_PKTLEN, aue_intr,
 	    AUE_INTR_INTERVAL);
 	if (err) {
 		printf("aue%d: open intr pipe failed: %s\n",
@@ -1267,12 +1218,12 @@ aue_init(void *xsc)
 #endif
 
 	/* Start up the receive pipe. */
-	for (i = 0; i < AUE_RX_LIST_CNT; i++) {
-		c = &sc->aue_cdata.aue_rx_chain[i];
-		usbd_setup_xfer(c->aue_xfer, sc->aue_ep[AUE_ENDPT_RX],
-		    c, mtod(c->aue_mbuf, char *), AUE_BUFSZ,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->aue_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->aue_ep[AUE_ENDPT_RX],
+		    c, mtod(c->ue_mbuf, char *), UE_BUFSZ,
 	    	USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, aue_rxeof);
-		usbd_transfer(c->aue_xfer);
+		usbd_transfer(c->ue_xfer);
 	}
 
 	ifp->if_flags |= IFF_RUNNING;
@@ -1375,7 +1326,7 @@ Static void
 aue_watchdog(struct ifnet *ifp)
 {
 	struct aue_softc	*sc = ifp->if_softc;
-	struct aue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		stat;
 
 	AUE_LOCK(sc);
@@ -1383,9 +1334,9 @@ aue_watchdog(struct ifnet *ifp)
 	ifp->if_oerrors++;
 	printf("aue%d: watchdog timeout\n", sc->aue_unit);
 
-	c = &sc->aue_cdata.aue_tx_chain[0];
-	usbd_get_xfer_status(c->aue_xfer, NULL, NULL, NULL, &stat);
-	aue_txeof(c->aue_xfer, c, stat);
+	c = &sc->aue_cdata.ue_tx_chain[0];
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &stat);
+	aue_txeof(c->ue_xfer, c, stat);
 
 	if (ifp->if_snd.ifq_head != NULL)
 		aue_start(ifp);
@@ -1459,40 +1410,13 @@ aue_stop(struct aue_softc *sc)
 #endif
 
 	/* Free RX resources. */
-	for (i = 0; i < AUE_RX_LIST_CNT; i++) {
-		if (sc->aue_cdata.aue_rx_chain[i].aue_buf != NULL) {
-			free(sc->aue_cdata.aue_rx_chain[i].aue_buf, M_USBDEV);
-			sc->aue_cdata.aue_rx_chain[i].aue_buf = NULL;
-		}
-		if (sc->aue_cdata.aue_rx_chain[i].aue_mbuf != NULL) {
-			m_freem(sc->aue_cdata.aue_rx_chain[i].aue_mbuf);
-			sc->aue_cdata.aue_rx_chain[i].aue_mbuf = NULL;
-		}
-		if (sc->aue_cdata.aue_rx_chain[i].aue_xfer != NULL) {
-			usbd_free_xfer(sc->aue_cdata.aue_rx_chain[i].aue_xfer);
-			sc->aue_cdata.aue_rx_chain[i].aue_xfer = NULL;
-		}
-	}
-
+	usb_ether_rx_list_free(&sc->aue_cdata);
 	/* Free TX resources. */
-	for (i = 0; i < AUE_TX_LIST_CNT; i++) {
-		if (sc->aue_cdata.aue_tx_chain[i].aue_buf != NULL) {
-			free(sc->aue_cdata.aue_tx_chain[i].aue_buf, M_USBDEV);
-			sc->aue_cdata.aue_tx_chain[i].aue_buf = NULL;
-		}
-		if (sc->aue_cdata.aue_tx_chain[i].aue_mbuf != NULL) {
-			m_freem(sc->aue_cdata.aue_tx_chain[i].aue_mbuf);
-			sc->aue_cdata.aue_tx_chain[i].aue_mbuf = NULL;
-		}
-		if (sc->aue_cdata.aue_tx_chain[i].aue_xfer != NULL) {
-			usbd_free_xfer(sc->aue_cdata.aue_tx_chain[i].aue_xfer);
-			sc->aue_cdata.aue_tx_chain[i].aue_xfer = NULL;
-		}
-	}
+	usb_ether_tx_list_free(&sc->aue_cdata);
 
 #ifdef AUE_INTR_PIPE
-	free(sc->aue_cdata.aue_ibuf, M_USBDEV);
-	sc->aue_cdata.aue_ibuf = NULL;
+	free(sc->aue_cdata.ue_ibuf, M_USBDEV);
+	sc->aue_cdata.ue_ibuf = NULL;
 #endif
 
 	sc->aue_link = 0;
diff --git a/sys/dev/usb/if_auereg.h b/sys/dev/usb/if_auereg.h
index 6c445dd..b9e4dd7 100644
--- a/sys/dev/usb/if_auereg.h
+++ b/sys/dev/usb/if_auereg.h
@@ -196,29 +196,6 @@ struct aue_rxpkt {
 #define AUE_RXSTAT_DRIBBLE	0x10
 #define AUE_RXSTAT_MASK		0x1E
 
-#define AUE_TX_LIST_CNT		1
-#define AUE_RX_LIST_CNT		1
-
-struct aue_softc;
-
-struct aue_chain {
-	struct aue_softc	*aue_sc;
-	usbd_xfer_handle	aue_xfer;
-	char			*aue_buf;
-	struct mbuf		*aue_mbuf;
-	int			aue_idx;
-};
-
-struct aue_cdata {
-	struct aue_chain	aue_tx_chain[AUE_TX_LIST_CNT];
-	struct aue_chain	aue_rx_chain[AUE_RX_LIST_CNT];
-	struct aue_intrpkt	*aue_ibuf;
-	int			aue_tx_prod;
-	int			aue_tx_cons;
-	int			aue_tx_cnt;
-	int			aue_rx_prod;
-};
-
 #define AUE_INC(x, y)		(x) = (x + 1) % y
 
 struct aue_softc {
@@ -241,7 +218,7 @@ struct aue_softc {
 	int			aue_unit;
 	u_int8_t		aue_link;
 	int			aue_if_flags;
-	struct aue_cdata	aue_cdata;
+	struct ue_cdata		aue_cdata;
 	struct callout_handle	aue_stat_ch;
 #if __FreeBSD_version >= 500000
 	struct mtx		aue_mtx;
@@ -261,6 +238,5 @@ struct aue_softc {
 #endif
 
 #define AUE_TIMEOUT		1000
-#define AUE_BUFSZ		1536
 #define AUE_MIN_FRAMELEN	60
 #define AUE_INTR_INTERVAL	100 /* ms */
diff --git a/sys/dev/usb/if_axe.c b/sys/dev/usb/if_axe.c
index 141c7dc..777496f 100644
--- a/sys/dev/usb/if_axe.c
+++ b/sys/dev/usb/if_axe.c
@@ -124,8 +124,6 @@ Static int axe_match(device_ptr_t);
 Static int axe_attach(device_ptr_t);
 Static int axe_detach(device_ptr_t);
 
-Static int axe_tx_list_init(struct axe_softc *);
-Static int axe_rx_list_init(struct axe_softc *);
 Static int axe_encap(struct axe_softc *, struct mbuf *, int);
 Static void axe_rxeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
 Static void axe_txeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -561,79 +559,30 @@ axe_detach(device_ptr_t dev)
 	return(0);
 }
 
-Static int
-axe_rx_list_init(struct axe_softc *sc)
-{
-	struct axe_cdata	*cd;
-	struct axe_chain	*c;
-	int			i;
-
-	cd = &sc->axe_cdata;
-	for (i = 0; i < AXE_RX_LIST_CNT; i++) {
-		c = &cd->axe_rx_chain[i];
-		c->axe_sc = sc;
-		c->axe_idx = i;
-		c->axe_mbuf = usb_ether_newbuf(USBDEVNAME(sc->axe_dev));
-		if (c->axe_mbuf == NULL)
-			return(ENOBUFS);
-		if (c->axe_xfer == NULL) {
-			c->axe_xfer = usbd_alloc_xfer(sc->axe_udev);
-			if (c->axe_xfer == NULL)
-				return(ENOBUFS);
-		}
-	}
-
-	return(0);
-}
-
-Static int
-axe_tx_list_init(struct axe_softc *sc)
-{
-	struct axe_cdata	*cd;
-	struct axe_chain	*c;
-	int			i;
-
-	cd = &sc->axe_cdata;
-	for (i = 0; i < AXE_TX_LIST_CNT; i++) {
-		c = &cd->axe_tx_chain[i];
-		c->axe_sc = sc;
-		c->axe_idx = i;
-		c->axe_mbuf = NULL;
-		if (c->axe_xfer == NULL) {
-			c->axe_xfer = usbd_alloc_xfer(sc->axe_udev);
-			if (c->axe_xfer == NULL)
-				return(ENOBUFS);
-		}
-		c->axe_buf = malloc(AXE_BUFSZ, M_USBDEV, M_NOWAIT);
-		if (c->axe_buf == NULL)
-			return(ENOBUFS);
-	}
-
-	return(0);
-}
-
 Static void
 axe_rxstart(struct ifnet *ifp)
 {
 	struct axe_softc	*sc;
-	struct axe_chain	*c;
+	struct ue_chain	*c;
 
 	sc = ifp->if_softc;
 	AXE_LOCK(sc);
-	c = &sc->axe_cdata.axe_rx_chain[sc->axe_cdata.axe_rx_prod];
+	c = &sc->axe_cdata.ue_rx_chain[sc->axe_cdata.ue_rx_prod];
 
-	c->axe_mbuf = usb_ether_newbuf(USBDEVNAME(sc->axe_dev));
-	if (c->axe_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->axe_dev));
 		ifp->if_ierrors++;
 		AXE_UNLOCK(sc);
 		return;
 	}
 
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->axe_xfer, sc->axe_ep[AXE_ENDPT_RX],
-	    c, mtod(c->axe_mbuf, char *), AXE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->axe_ep[AXE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, axe_rxeof);
-	usbd_transfer(c->axe_xfer);
+	usbd_transfer(c->ue_xfer);
 	AXE_UNLOCK(sc);
 
 	return;
@@ -647,13 +596,13 @@ Static void
 axe_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
 	struct axe_softc	*sc;
-	struct axe_chain	*c;
+	struct ue_chain	*c;
         struct mbuf		*m;
         struct ifnet		*ifp;
 	int			total_len = 0;
 
 	c = priv;
-	sc = c->axe_sc;
+	sc = c->ue_sc;
 	AXE_LOCK(sc);
 	ifp = &sc->arpcom.ac_if;
 
@@ -677,7 +626,7 @@ axe_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	usbd_get_xfer_status(xfer, NULL, NULL, &total_len, NULL);
 
-	m = c->axe_mbuf;
+	m = c->ue_mbuf;
 
 	if (total_len < sizeof(struct ether_header)) {
 		ifp->if_ierrors++;
@@ -695,10 +644,10 @@ axe_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 	return;
 done:
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->axe_xfer, sc->axe_ep[AXE_ENDPT_RX],
-	    c, mtod(c->axe_mbuf, char *), AXE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->axe_ep[AXE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, axe_rxeof);
-	usbd_transfer(c->axe_xfer);
+	usbd_transfer(c->ue_xfer);
 	AXE_UNLOCK(sc);
 
 	return;
@@ -713,12 +662,12 @@ Static void
 axe_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
 	struct axe_softc	*sc;
-	struct axe_chain	*c;
+	struct ue_chain	*c;
 	struct ifnet		*ifp;
 	usbd_status		err;
 
 	c = priv;
-	sc = c->axe_sc;
+	sc = c->ue_sc;
 	AXE_LOCK(sc);
 	ifp = &sc->arpcom.ac_if;
 
@@ -737,12 +686,12 @@ axe_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	ifp->if_timer = 0;
 	ifp->if_flags &= ~IFF_OACTIVE;
-	usbd_get_xfer_status(c->axe_xfer, NULL, NULL, NULL, &err);
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &err);
 
-	if (c->axe_mbuf != NULL) {
-		c->axe_mbuf->m_pkthdr.rcvif = ifp;
-		usb_tx_done(c->axe_mbuf);
-		c->axe_mbuf = NULL;
+	if (c->ue_mbuf != NULL) {
+		c->ue_mbuf->m_pkthdr.rcvif = ifp;
+		usb_tx_done(c->ue_mbuf);
+		c->ue_mbuf = NULL;
 	}
 
 	if (err)
@@ -794,30 +743,30 @@ axe_tick(void *xsc)
 Static int
 axe_encap(struct axe_softc *sc, struct mbuf *m, int idx)
 {
-	struct axe_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 
-	c = &sc->axe_cdata.axe_tx_chain[idx];
+	c = &sc->axe_cdata.ue_tx_chain[idx];
 
 	/*
 	 * Copy the mbuf data into a contiguous buffer, leaving two
 	 * bytes at the beginning to hold the frame length.
 	 */
-	m_copydata(m, 0, m->m_pkthdr.len, c->axe_buf);
-	c->axe_mbuf = m;
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf);
+	c->ue_mbuf = m;
 
-	usbd_setup_xfer(c->axe_xfer, sc->axe_ep[AXE_ENDPT_TX],
-	    c, c->axe_buf, m->m_pkthdr.len, USBD_FORCE_SHORT_XFER,
+	usbd_setup_xfer(c->ue_xfer, sc->axe_ep[AXE_ENDPT_TX],
+	    c, c->ue_buf, m->m_pkthdr.len, USBD_FORCE_SHORT_XFER,
 	    10000, axe_txeof);
 
 	/* Transmit */
-	err = usbd_transfer(c->axe_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (err != USBD_IN_PROGRESS) {
 		axe_stop(sc);
 		return(EIO);
 	}
 
-	sc->axe_cdata.axe_tx_cnt++;
+	sc->axe_cdata.ue_tx_cnt++;
 
 	return(0);
 }
@@ -876,7 +825,7 @@ axe_init(void *xsc)
 {
 	struct axe_softc	*sc = xsc;
 	struct ifnet		*ifp = &sc->arpcom.ac_if;
-	struct axe_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 	int			i;
 	int			rxmode;
@@ -900,14 +849,16 @@ axe_init(void *xsc)
 	/* Enable RX logic. */
 
 	/* Init TX ring. */
-	if (axe_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->axe_cdata,
+	    USBDEVNAME(sc->axe_dev), sc->axe_udev) == ENOBUFS) {
 		printf("axe%d: tx list init failed\n", sc->axe_unit);
 		AXE_UNLOCK(sc);
 		return;
 	}
 
 	/* Init RX ring. */
-	if (axe_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->axe_cdata,
+	    USBDEVNAME(sc->axe_dev), sc->axe_udev) == ENOBUFS) {
 		printf("axe%d: rx list init failed\n", sc->axe_unit);
 		AXE_UNLOCK(sc);
 		return;
@@ -953,12 +904,12 @@ axe_init(void *xsc)
 	}
 
 	/* Start up the receive pipe. */
-	for (i = 0; i < AXE_RX_LIST_CNT; i++) {
-		c = &sc->axe_cdata.axe_rx_chain[i];
-		usbd_setup_xfer(c->axe_xfer, sc->axe_ep[AXE_ENDPT_RX],
-		    c, mtod(c->axe_mbuf, char *), AXE_BUFSZ,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->axe_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->axe_ep[AXE_ENDPT_RX],
+		    c, mtod(c->ue_mbuf, char *), UE_BUFSZ,
 		    USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, axe_rxeof);
-		usbd_transfer(c->axe_xfer);
+		usbd_transfer(c->ue_xfer);
 	}
 
 	ifp->if_flags |= IFF_RUNNING;
@@ -1039,7 +990,7 @@ Static void
 axe_watchdog(struct ifnet *ifp)
 {
 	struct axe_softc	*sc;
-	struct axe_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		stat;
 
 	sc = ifp->if_softc;
@@ -1048,9 +999,9 @@ axe_watchdog(struct ifnet *ifp)
 	ifp->if_oerrors++;
 	printf("axe%d: watchdog timeout\n", sc->axe_unit);
 
-	c = &sc->axe_cdata.axe_tx_chain[0];
-	usbd_get_xfer_status(c->axe_xfer, NULL, NULL, NULL, &stat);
-	axe_txeof(c->axe_xfer, c, stat);
+	c = &sc->axe_cdata.ue_tx_chain[0];
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &stat);
+	axe_txeof(c->ue_xfer, c, stat);
 
 	AXE_UNLOCK(sc);
 
@@ -1124,36 +1075,9 @@ axe_stop(struct axe_softc *sc)
 	axe_reset(sc);
 
 	/* Free RX resources. */
-	for (i = 0; i < AXE_RX_LIST_CNT; i++) {
-		if (sc->axe_cdata.axe_rx_chain[i].axe_buf != NULL) {
-			free(sc->axe_cdata.axe_rx_chain[i].axe_buf, M_USBDEV);
-			sc->axe_cdata.axe_rx_chain[i].axe_buf = NULL;
-		}
-		if (sc->axe_cdata.axe_rx_chain[i].axe_mbuf != NULL) {
-			m_freem(sc->axe_cdata.axe_rx_chain[i].axe_mbuf);
-			sc->axe_cdata.axe_rx_chain[i].axe_mbuf = NULL;
-		}
-		if (sc->axe_cdata.axe_rx_chain[i].axe_xfer != NULL) {
-			usbd_free_xfer(sc->axe_cdata.axe_rx_chain[i].axe_xfer);
-			sc->axe_cdata.axe_rx_chain[i].axe_xfer = NULL;
-		}
-	}
-
+	usb_ether_rx_list_free(&sc->axe_cdata);
 	/* Free TX resources. */
-	for (i = 0; i < AXE_TX_LIST_CNT; i++) {
-		if (sc->axe_cdata.axe_tx_chain[i].axe_buf != NULL) {
-			free(sc->axe_cdata.axe_tx_chain[i].axe_buf, M_USBDEV);
-			sc->axe_cdata.axe_tx_chain[i].axe_buf = NULL;
-		}
-		if (sc->axe_cdata.axe_tx_chain[i].axe_mbuf != NULL) {
-			m_freem(sc->axe_cdata.axe_tx_chain[i].axe_mbuf);
-			sc->axe_cdata.axe_tx_chain[i].axe_mbuf = NULL;
-		}
-		if (sc->axe_cdata.axe_tx_chain[i].axe_xfer != NULL) {
-			usbd_free_xfer(sc->axe_cdata.axe_tx_chain[i].axe_xfer);
-			sc->axe_cdata.axe_tx_chain[i].axe_xfer = NULL;
-		}
-	}
+	usb_ether_tx_list_free(&sc->axe_cdata);
 
 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
         sc->axe_link = 0;
diff --git a/sys/dev/usb/if_axereg.h b/sys/dev/usb/if_axereg.h
index 5892c67..d825d79 100644
--- a/sys/dev/usb/if_axereg.h
+++ b/sys/dev/usb/if_axereg.h
@@ -93,14 +93,10 @@
 #define AXE_NOPHY				0xE0
 
 #define AXE_TIMEOUT		1000
-#define AXE_BUFSZ		1536
 #define AXE_MIN_FRAMELEN	60
 #define AXE_RX_FRAMES		1
 #define AXE_TX_FRAMES		1
 
-#define AXE_RX_LIST_CNT		1
-#define AXE_TX_LIST_CNT		1
-
 #define AXE_CTL_READ		0x01
 #define AXE_CTL_WRITE		0x02
 
@@ -121,25 +117,6 @@ struct axe_type {
 	u_int16_t		axe_did;
 };
 
-struct axe_softc;
-
-struct axe_chain {
-	struct axe_softc	*axe_sc;
-	usbd_xfer_handle	axe_xfer;
-	char			*axe_buf;
-	struct mbuf		*axe_mbuf;
-	int			axe_idx;
-};
-
-struct axe_cdata {
-	struct axe_chain	axe_tx_chain[AXE_TX_LIST_CNT];
-	struct axe_chain	axe_rx_chain[AXE_RX_LIST_CNT];
-	int			axe_tx_prod;
-	int			axe_tx_cons;
-	int			axe_tx_cnt;
-	int			axe_rx_prod;
-};
-
 #define AXE_INC(x, y)		(x) = (x + 1) % y
 
 struct axe_softc {
@@ -159,7 +136,7 @@ struct axe_softc {
 	usbd_pipe_handle	axe_ep[AXE_ENDPT_MAX];
 	int			axe_unit;
 	int			axe_if_flags;
-	struct axe_cdata	axe_cdata;
+	struct ue_cdata		axe_cdata;
 	struct callout_handle	axe_stat_ch;
 #if __FreeBSD_version >= 500000
 	struct mtx		axe_mtx;
diff --git a/sys/dev/usb/if_cdce.c b/sys/dev/usb/if_cdce.c
index 45b2216..ff2961f 100644
--- a/sys/dev/usb/if_cdce.c
+++ b/sys/dev/usb/if_cdce.c
@@ -81,8 +81,6 @@ USB_DECLARE_DRIVER_INIT(cdce,
 DRIVER_MODULE(cdce, uhub, cdce_driver, cdce_devclass, usbd_driver_load, 0);
 MODULE_VERSION(cdce, 0);
 
-Static int	 cdce_tx_list_init(struct cdce_softc *);
-Static int	 cdce_rx_list_init(struct cdce_softc *);
 Static int	 cdce_encap(struct cdce_softc *, struct mbuf *, int);
 Static void	 cdce_rxeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
 Static void	 cdce_txeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -373,32 +371,32 @@ cdce_start(struct ifnet *ifp)
 Static int
 cdce_encap(struct cdce_softc *sc, struct mbuf *m, int idx)
 {
-	struct cdce_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		 err;
 	int			 extra = 0;
 
-	c = &sc->cdce_cdata.cdce_tx_chain[idx];
+	c = &sc->cdce_cdata.ue_tx_chain[idx];
 
-	m_copydata(m, 0, m->m_pkthdr.len, c->cdce_buf);
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf);
 	if (sc->cdce_flags & CDCE_ZAURUS) {
 		/* Zaurus wants a 32-bit CRC appended to every frame */
 		u_int32_t crc;
 
-		crc = htole32(crc32(c->cdce_buf, m->m_pkthdr.len));
-		bcopy(&crc, c->cdce_buf + m->m_pkthdr.len, 4);
+		crc = htole32(crc32(c->ue_buf, m->m_pkthdr.len));
+		bcopy(&crc, c->ue_buf + m->m_pkthdr.len, 4);
 		extra = 4;
 	}
-	c->cdce_mbuf = m;
+	c->ue_mbuf = m;
 
-	usbd_setup_xfer(c->cdce_xfer, sc->cdce_bulkout_pipe, c, c->cdce_buf,
+	usbd_setup_xfer(c->ue_xfer, sc->cdce_bulkout_pipe, c, c->ue_buf,
 	    m->m_pkthdr.len + extra, 0, 10000, cdce_txeof);
-	err = usbd_transfer(c->cdce_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (err != USBD_IN_PROGRESS) {
 		cdce_stop(sc);
 		return (EIO);
 	}
 
-	sc->cdce_cdata.cdce_tx_cnt++;
+	sc->cdce_cdata.ue_tx_cnt++;
 
 	return (0);
 }
@@ -441,27 +439,8 @@ cdce_stop(struct cdce_softc *sc)
 		sc->cdce_bulkout_pipe = NULL;
 	}
 
-	for (i = 0; i < CDCE_RX_LIST_CNT; i++) {
-		if (sc->cdce_cdata.cdce_rx_chain[i].cdce_mbuf != NULL) {
-			m_freem(sc->cdce_cdata.cdce_rx_chain[i].cdce_mbuf);
-			sc->cdce_cdata.cdce_rx_chain[i].cdce_mbuf = NULL;
-		}
-		if (sc->cdce_cdata.cdce_rx_chain[i].cdce_xfer != NULL) {
-			usbd_free_xfer(sc->cdce_cdata.cdce_rx_chain[i].cdce_xfer);
-			sc->cdce_cdata.cdce_rx_chain[i].cdce_xfer = NULL;
-		}
-	}
-
-	for (i = 0; i < CDCE_TX_LIST_CNT; i++) {
-		if (sc->cdce_cdata.cdce_tx_chain[i].cdce_mbuf != NULL) {
-			m_freem(sc->cdce_cdata.cdce_tx_chain[i].cdce_mbuf);
-			sc->cdce_cdata.cdce_tx_chain[i].cdce_mbuf = NULL;
-		}
-		if (sc->cdce_cdata.cdce_tx_chain[i].cdce_xfer != NULL) {
-			usbd_free_xfer(sc->cdce_cdata.cdce_tx_chain[i].cdce_xfer);
-			sc->cdce_cdata.cdce_tx_chain[i].cdce_xfer = NULL;
-		}
-	}
+	usb_ether_rx_list_free(&sc->cdce_cdata);
+	usb_ether_tx_list_free(&sc->cdce_cdata);
 
 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
 	CDCE_UNLOCK(sc);
@@ -521,7 +500,7 @@ cdce_init(void *xsc)
 {
 	struct cdce_softc	*sc = xsc;
 	struct ifnet		*ifp = GET_IFP(sc);
-	struct cdce_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		 err;
 	int			 i;
 
@@ -531,13 +510,15 @@ cdce_init(void *xsc)
 	CDCE_LOCK(sc);
 	cdce_reset(sc);
 
-	if (cdce_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->cdce_cdata,
+	    USBDEVNAME(sc->cdce_dev), sc->cdce_udev) == ENOBUFS) {
 		printf("%s: tx list init failed\n", USBDEVNAME(sc->cdce_dev));
 		CDCE_UNLOCK(sc);
 		return;
 	}
 
-	if (cdce_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->cdce_cdata,
+	    USBDEVNAME(sc->cdce_dev), sc->cdce_udev) == ENOBUFS) {
 		printf("%s: rx list init failed\n", USBDEVNAME(sc->cdce_dev));
 		CDCE_UNLOCK(sc);
 		return;
@@ -563,12 +544,12 @@ cdce_init(void *xsc)
 		return;
 	}
 
-	for (i = 0; i < CDCE_RX_LIST_CNT; i++) {
-		c = &sc->cdce_cdata.cdce_rx_chain[i];
-		usbd_setup_xfer(c->cdce_xfer, sc->cdce_bulkin_pipe, c,
-		    mtod(c->cdce_mbuf, char *), CDCE_BUFSZ, USBD_SHORT_XFER_OK,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->cdce_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->cdce_bulkin_pipe, c,
+		    mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 		    USBD_NO_TIMEOUT, cdce_rxeof);
-		usbd_transfer(c->cdce_xfer);
+		usbd_transfer(c->ue_xfer);
 	}
 
 	ifp->if_flags |= IFF_RUNNING;
@@ -579,65 +560,11 @@ cdce_init(void *xsc)
 	return;
 }
 
-Static int
-cdce_rx_list_init(struct cdce_softc *sc)
-{
-	struct cdce_cdata	*cd;
-	struct cdce_chain	*c;
-	int			 i;
-
-	cd = &sc->cdce_cdata;
-	for (i = 0; i < CDCE_RX_LIST_CNT; i++) {
-		c = &cd->cdce_rx_chain[i];
-		c->cdce_sc = sc;
-		c->cdce_idx = i;
-		c->cdce_mbuf = usb_ether_newbuf(USBDEVNAME(sc->cdce_dev));
-		if (c->cdce_mbuf == NULL)
-			return (ENOBUFS);
-		if (c->cdce_xfer == NULL) {
-			c->cdce_xfer = usbd_alloc_xfer(sc->cdce_udev);
-			if (c->cdce_xfer == NULL)
-				return (ENOBUFS);
-			c->cdce_buf = usbd_alloc_buffer(c->cdce_xfer, CDCE_BUFSZ);
-			if (c->cdce_buf == NULL)
-				return (ENOBUFS);
-		}
-	}
-
-	return (0);
-}
-
-Static int
-cdce_tx_list_init(struct cdce_softc *sc)
-{
-	struct cdce_cdata	*cd;
-	struct cdce_chain	*c;
-	int			 i;
-
-	cd = &sc->cdce_cdata;
-	for (i = 0; i < CDCE_TX_LIST_CNT; i++) {
-		c = &cd->cdce_tx_chain[i];
-		c->cdce_sc = sc;
-		c->cdce_idx = i;
-		c->cdce_mbuf = NULL;
-		if (c->cdce_xfer == NULL) {
-			c->cdce_xfer = usbd_alloc_xfer(sc->cdce_udev);
-			if (c->cdce_xfer == NULL)
-				return (ENOBUFS);
-			c->cdce_buf = usbd_alloc_buffer(c->cdce_xfer, CDCE_BUFSZ);
-			if (c->cdce_buf == NULL)
-				return (ENOBUFS);
-		}
-	}
-
-	return (0);
-}
-
 Static void
 cdce_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct cdce_chain	*c = priv;
-	struct cdce_softc	*sc = c->cdce_sc;
+	struct ue_chain	*c = priv;
+	struct cdce_softc	*sc = c->ue_sc;
 	struct ifnet		*ifp;
 	struct mbuf		*m;
 	int			 total_len = 0;
@@ -672,7 +599,7 @@ cdce_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 	if (sc->cdce_flags & CDCE_ZAURUS)
 		total_len -= 4;	/* Strip off CRC added by Zaurus */
 
-	m = c->cdce_mbuf;
+	m = c->ue_mbuf;
 
 	if (total_len < sizeof(struct ether_header)) {
 		ifp->if_ierrors++;
@@ -691,11 +618,11 @@ cdce_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 done:
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->cdce_xfer, sc->cdce_bulkin_pipe, c,
-	    mtod(c->cdce_mbuf, char *),
-	    CDCE_BUFSZ, USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT,
+	usbd_setup_xfer(c->ue_xfer, sc->cdce_bulkin_pipe, c,
+	    mtod(c->ue_mbuf, char *),
+	    UE_BUFSZ, USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT,
 	    cdce_rxeof);
-	usbd_transfer(c->cdce_xfer);
+	usbd_transfer(c->ue_xfer);
 	CDCE_UNLOCK(sc);
 
 	return;
@@ -704,8 +631,8 @@ done:
 Static void
 cdce_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct cdce_chain	*c = priv;
-	struct cdce_softc	*sc = c->cdce_sc;
+	struct ue_chain	*c = priv;
+	struct cdce_softc	*sc = c->ue_sc;
 	struct ifnet		*ifp;
 	usbd_status		 err;
 
@@ -733,12 +660,12 @@ cdce_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 	}
 
 	ifp->if_flags &= ~IFF_OACTIVE;
-	usbd_get_xfer_status(c->cdce_xfer, NULL, NULL, NULL, &err);
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &err);
 
-	if (c->cdce_mbuf != NULL) {
-		c->cdce_mbuf->m_pkthdr.rcvif = ifp;
-		usb_tx_done(c->cdce_mbuf);
-		c->cdce_mbuf = NULL;
+	if (c->ue_mbuf != NULL) {
+		c->ue_mbuf->m_pkthdr.rcvif = ifp;
+		usb_tx_done(c->ue_mbuf);
+		c->ue_mbuf = NULL;
 	}
 
 	if (err)
@@ -755,7 +682,7 @@ Static void
 cdce_rxstart(struct ifnet *ifp)
 {
 	struct cdce_softc   *sc;
-	struct cdce_chain   *c;
+	struct ue_chain   *c;
 
 	sc = ifp->if_softc;
 	CDCE_LOCK(sc);
@@ -765,19 +692,21 @@ cdce_rxstart(struct ifnet *ifp)
 		return;
 	}
 
-	c = &sc->cdce_cdata.cdce_rx_chain[sc->cdce_cdata.cdce_rx_prod];
+	c = &sc->cdce_cdata.ue_rx_chain[sc->cdce_cdata.ue_rx_prod];
 
-	c->cdce_mbuf = usb_ether_newbuf(USBDEVNAME(sc->cdce_dev));
-	if (c->cdce_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->cdce_dev));
 		ifp->if_ierrors++;
 		CDCE_UNLOCK(sc);
 		return;
 	}
 
-	usbd_setup_xfer(c->cdce_xfer, sc->cdce_bulkin_pipe, c,
-	    mtod(c->cdce_mbuf, char *), CDCE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->cdce_bulkin_pipe, c,
+	    mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, cdce_rxeof);
-	usbd_transfer(c->cdce_xfer);
+	usbd_transfer(c->ue_xfer);
 
 	CDCE_UNLOCK(sc);
 	return;
diff --git a/sys/dev/usb/if_cdcereg.h b/sys/dev/usb/if_cdcereg.h
index a0ef317e..48efdbe 100644
--- a/sys/dev/usb/if_cdcereg.h
+++ b/sys/dev/usb/if_cdcereg.h
@@ -35,10 +35,6 @@
 #ifndef _USB_IF_CDCEREG_H_
 #define _USB_IF_CDCEREG_H_
 
-#define CDCE_RX_LIST_CNT	1
-#define CDCE_TX_LIST_CNT	1
-#define CDCE_BUFSZ		1542
-
 struct cdce_type {
 	struct usb_devno	 cdce_dev;
 	u_int16_t		 cdce_flags;
@@ -46,25 +42,6 @@ struct cdce_type {
 #define CDCE_NO_UNION	2
 };
 
-struct cdce_softc;
-
-struct cdce_chain {
-	struct cdce_softc	*cdce_sc;
-	usbd_xfer_handle	 cdce_xfer;
-	char			*cdce_buf;
-	struct mbuf		*cdce_mbuf;
-	int			 cdce_idx;
-};
-
-struct cdce_cdata {
-	struct cdce_chain	 cdce_tx_chain[CDCE_TX_LIST_CNT];
-	struct cdce_chain	 cdce_rx_chain[CDCE_TX_LIST_CNT];
-	int			 cdce_tx_prod;
-	int			 cdce_tx_cons;
-	int			 cdce_tx_cnt;
-	int			 cdce_rx_prod;
-};
-
 struct cdce_softc {
 	struct arpcom		 arpcom;
 #define GET_IFP(sc) (&(sc)->arpcom.ac_if)
@@ -79,7 +56,7 @@ struct cdce_softc {
 	device_t		 cdce_dev;
 	int			 cdce_unit;
 
-	struct cdce_cdata	 cdce_cdata;
+	struct ue_cdata		 cdce_cdata;
 	struct timeval		 cdce_rx_notice;
 	int			 cdce_rxeof_errors;
 
diff --git a/sys/dev/usb/if_cue.c b/sys/dev/usb/if_cue.c
index 70e5b75..29723fc 100644
--- a/sys/dev/usb/if_cue.c
+++ b/sys/dev/usb/if_cue.c
@@ -96,8 +96,6 @@ Static int cue_match(device_ptr_t);
 Static int cue_attach(device_ptr_t);
 Static int cue_detach(device_ptr_t);
 
-Static int cue_tx_list_init(struct cue_softc *);
-Static int cue_rx_list_init(struct cue_softc *);
 Static int cue_encap(struct cue_softc *, struct mbuf *, int);
 Static void cue_rxeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
 Static void cue_txeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -568,79 +566,30 @@ cue_detach(device_ptr_t dev)
 	return(0);
 }
 
-Static int
-cue_rx_list_init(struct cue_softc *sc)
-{
-	struct cue_cdata	*cd;
-	struct cue_chain	*c;
-	int			i;
-
-	cd = &sc->cue_cdata;
-	for (i = 0; i < CUE_RX_LIST_CNT; i++) {
-		c = &cd->cue_rx_chain[i];
-		c->cue_sc = sc;
-		c->cue_idx = i;
-		c->cue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->cue_dev));
-		if (c->cue_mbuf == NULL)
-			return(ENOBUFS);
-		if (c->cue_xfer == NULL) {
-			c->cue_xfer = usbd_alloc_xfer(sc->cue_udev);
-			if (c->cue_xfer == NULL)
-				return(ENOBUFS);
-		}
-	}
-
-	return(0);
-}
-
-Static int
-cue_tx_list_init(struct cue_softc *sc)
-{
-	struct cue_cdata	*cd;
-	struct cue_chain	*c;
-	int			i;
-
-	cd = &sc->cue_cdata;
-	for (i = 0; i < CUE_TX_LIST_CNT; i++) {
-		c = &cd->cue_tx_chain[i];
-		c->cue_sc = sc;
-		c->cue_idx = i;
-		c->cue_mbuf = NULL;
-		if (c->cue_xfer == NULL) {
-			c->cue_xfer = usbd_alloc_xfer(sc->cue_udev);
-			if (c->cue_xfer == NULL)
-				return(ENOBUFS);
-		}
-		c->cue_buf = malloc(CUE_BUFSZ, M_USBDEV, M_NOWAIT);
-		if (c->cue_buf == NULL)
-			return(ENOBUFS);
-	}
-
-	return(0);
-}
-
 Static void
 cue_rxstart(struct ifnet *ifp)
 {
 	struct cue_softc	*sc;
-	struct cue_chain	*c;
+	struct ue_chain	*c;
 
 	sc = ifp->if_softc;
 	CUE_LOCK(sc);
-	c = &sc->cue_cdata.cue_rx_chain[sc->cue_cdata.cue_rx_prod];
+	c = &sc->cue_cdata.ue_rx_chain[sc->cue_cdata.ue_rx_prod];
 
-	c->cue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->cue_dev));
-	if (c->cue_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->cue_dev));
 		ifp->if_ierrors++;
 		CUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->cue_xfer, sc->cue_ep[CUE_ENDPT_RX],
-	    c, mtod(c->cue_mbuf, char *), CUE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->cue_ep[CUE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, cue_rxeof);
-	usbd_transfer(c->cue_xfer);
+	usbd_transfer(c->ue_xfer);
 	CUE_UNLOCK(sc);
 
 	return;
@@ -654,14 +603,14 @@ Static void
 cue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
 	struct cue_softc	*sc;
-	struct cue_chain	*c;
+	struct ue_chain	*c;
         struct mbuf		*m;
         struct ifnet		*ifp;
 	int			total_len = 0;
 	u_int16_t		len;
 
 	c = priv;
-	sc = c->cue_sc;
+	sc = c->ue_sc;
 	CUE_LOCK(sc);
 	ifp = &sc->arpcom.ac_if;
 
@@ -685,7 +634,7 @@ cue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	usbd_get_xfer_status(xfer, NULL, NULL, &total_len, NULL);
 
-	m = c->cue_mbuf;
+	m = c->ue_mbuf;
 	len = *mtod(m, u_int16_t *);
 
 	/* No errors; receive the packet. */
@@ -708,10 +657,10 @@ cue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 	return;
 done:
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->cue_xfer, sc->cue_ep[CUE_ENDPT_RX],
-	    c, mtod(c->cue_mbuf, char *), CUE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->cue_ep[CUE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, cue_rxeof);
-	usbd_transfer(c->cue_xfer);
+	usbd_transfer(c->ue_xfer);
 	CUE_UNLOCK(sc);
 
 	return;
@@ -726,12 +675,12 @@ Static void
 cue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
 	struct cue_softc	*sc;
-	struct cue_chain	*c;
+	struct ue_chain	*c;
 	struct ifnet		*ifp;
 	usbd_status		err;
 
 	c = priv;
-	sc = c->cue_sc;
+	sc = c->ue_sc;
 	CUE_LOCK(sc);
 	ifp = &sc->arpcom.ac_if;
 
@@ -750,12 +699,12 @@ cue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	ifp->if_timer = 0;
 	ifp->if_flags &= ~IFF_OACTIVE;
-	usbd_get_xfer_status(c->cue_xfer, NULL, NULL, NULL, &err);
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &err);
 
-	if (c->cue_mbuf != NULL) {
-		c->cue_mbuf->m_pkthdr.rcvif = ifp;
-		usb_tx_done(c->cue_mbuf);
-		c->cue_mbuf = NULL;
+	if (c->ue_mbuf != NULL) {
+		c->ue_mbuf->m_pkthdr.rcvif = ifp;
+		usb_tx_done(c->ue_mbuf);
+		c->ue_mbuf = NULL;
 	}
 
 	if (err)
@@ -801,35 +750,35 @@ Static int
 cue_encap(struct cue_softc *sc, struct mbuf *m, int idx)
 {
 	int			total_len;
-	struct cue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 
-	c = &sc->cue_cdata.cue_tx_chain[idx];
+	c = &sc->cue_cdata.ue_tx_chain[idx];
 
 	/*
 	 * Copy the mbuf data into a contiguous buffer, leaving two
 	 * bytes at the beginning to hold the frame length.
 	 */
-	m_copydata(m, 0, m->m_pkthdr.len, c->cue_buf + 2);
-	c->cue_mbuf = m;
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf + 2);
+	c->ue_mbuf = m;
 
 	total_len = m->m_pkthdr.len + 2;
 
 	/* The first two bytes are the frame length */
-	c->cue_buf[0] = (u_int8_t)m->m_pkthdr.len;
-	c->cue_buf[1] = (u_int8_t)(m->m_pkthdr.len >> 8);
+	c->ue_buf[0] = (u_int8_t)m->m_pkthdr.len;
+	c->ue_buf[1] = (u_int8_t)(m->m_pkthdr.len >> 8);
 
-	usbd_setup_xfer(c->cue_xfer, sc->cue_ep[CUE_ENDPT_TX],
-	    c, c->cue_buf, total_len, 0, 10000, cue_txeof);
+	usbd_setup_xfer(c->ue_xfer, sc->cue_ep[CUE_ENDPT_TX],
+	    c, c->ue_buf, total_len, 0, 10000, cue_txeof);
 
 	/* Transmit */
-	err = usbd_transfer(c->cue_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (err != USBD_IN_PROGRESS) {
 		cue_stop(sc);
 		return(EIO);
 	}
 
-	sc->cue_cdata.cue_tx_cnt++;
+	sc->cue_cdata.ue_tx_cnt++;
 
 	return(0);
 }
@@ -883,7 +832,7 @@ cue_init(void *xsc)
 {
 	struct cue_softc	*sc = xsc;
 	struct ifnet		*ifp = &sc->arpcom.ac_if;
-	struct cue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 	int			i;
 
@@ -914,14 +863,16 @@ cue_init(void *xsc)
 	}
 
 	/* Init TX ring. */
-	if (cue_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->cue_cdata,
+	    USBDEVNAME(sc->cue_dev), sc->cue_udev) == ENOBUFS) {
 		printf("cue%d: tx list init failed\n", sc->cue_unit);
 		CUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Init RX ring. */
-	if (cue_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->cue_cdata,
+	    USBDEVNAME(sc->cue_dev), sc->cue_udev) == ENOBUFS) {
 		printf("cue%d: rx list init failed\n", sc->cue_unit);
 		CUE_UNLOCK(sc);
 		return;
@@ -963,12 +914,12 @@ cue_init(void *xsc)
 	}
 
 	/* Start up the receive pipe. */
-	for (i = 0; i < CUE_RX_LIST_CNT; i++) {
-		c = &sc->cue_cdata.cue_rx_chain[i];
-		usbd_setup_xfer(c->cue_xfer, sc->cue_ep[CUE_ENDPT_RX],
-		    c, mtod(c->cue_mbuf, char *), CUE_BUFSZ,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->cue_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->cue_ep[CUE_ENDPT_RX],
+		    c, mtod(c->ue_mbuf, char *), UE_BUFSZ,
 		    USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, cue_rxeof);
-		usbd_transfer(c->cue_xfer);
+		usbd_transfer(c->ue_xfer);
 	}
 
 	ifp->if_flags |= IFF_RUNNING;
@@ -1030,7 +981,7 @@ Static void
 cue_watchdog(struct ifnet *ifp)
 {
 	struct cue_softc	*sc;
-	struct cue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		stat;
 
 	sc = ifp->if_softc;
@@ -1039,9 +990,9 @@ cue_watchdog(struct ifnet *ifp)
 	ifp->if_oerrors++;
 	printf("cue%d: watchdog timeout\n", sc->cue_unit);
 
-	c = &sc->cue_cdata.cue_tx_chain[0];
-	usbd_get_xfer_status(c->cue_xfer, NULL, NULL, NULL, &stat);
-	cue_txeof(c->cue_xfer, c, stat);
+	c = &sc->cue_cdata.ue_tx_chain[0];
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &stat);
+	cue_txeof(c->ue_xfer, c, stat);
 
 	if (ifp->if_snd.ifq_head != NULL)
 		cue_start(ifp);
@@ -1114,36 +1065,9 @@ cue_stop(struct cue_softc *sc)
 	}
 
 	/* Free RX resources. */
-	for (i = 0; i < CUE_RX_LIST_CNT; i++) {
-		if (sc->cue_cdata.cue_rx_chain[i].cue_buf != NULL) {
-			free(sc->cue_cdata.cue_rx_chain[i].cue_buf, M_USBDEV);
-			sc->cue_cdata.cue_rx_chain[i].cue_buf = NULL;
-		}
-		if (sc->cue_cdata.cue_rx_chain[i].cue_mbuf != NULL) {
-			m_freem(sc->cue_cdata.cue_rx_chain[i].cue_mbuf);
-			sc->cue_cdata.cue_rx_chain[i].cue_mbuf = NULL;
-		}
-		if (sc->cue_cdata.cue_rx_chain[i].cue_xfer != NULL) {
-			usbd_free_xfer(sc->cue_cdata.cue_rx_chain[i].cue_xfer);
-			sc->cue_cdata.cue_rx_chain[i].cue_xfer = NULL;
-		}
-	}
-
+	usb_ether_rx_list_free(&sc->cue_cdata);
 	/* Free TX resources. */
-	for (i = 0; i < CUE_TX_LIST_CNT; i++) {
-		if (sc->cue_cdata.cue_tx_chain[i].cue_buf != NULL) {
-			free(sc->cue_cdata.cue_tx_chain[i].cue_buf, M_USBDEV);
-			sc->cue_cdata.cue_tx_chain[i].cue_buf = NULL;
-		}
-		if (sc->cue_cdata.cue_tx_chain[i].cue_mbuf != NULL) {
-			m_freem(sc->cue_cdata.cue_tx_chain[i].cue_mbuf);
-			sc->cue_cdata.cue_tx_chain[i].cue_mbuf = NULL;
-		}
-		if (sc->cue_cdata.cue_tx_chain[i].cue_xfer != NULL) {
-			usbd_free_xfer(sc->cue_cdata.cue_tx_chain[i].cue_xfer);
-			sc->cue_cdata.cue_tx_chain[i].cue_xfer = NULL;
-		}
-	}
+	usb_ether_tx_list_free(&sc->cue_cdata);
 
 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
 	CUE_UNLOCK(sc);
diff --git a/sys/dev/usb/if_cuereg.h b/sys/dev/usb/if_cuereg.h
index b364ec3..a3a861d 100644
--- a/sys/dev/usb/if_cuereg.h
+++ b/sys/dev/usb/if_cuereg.h
@@ -116,14 +116,10 @@
 #define CUE_MCAST_TABLE_LEN			64
 
 #define CUE_TIMEOUT		1000
-#define CUE_BUFSZ		1536
 #define CUE_MIN_FRAMELEN	60
 #define CUE_RX_FRAMES		1
 #define CUE_TX_FRAMES		1
 
-#define CUE_RX_LIST_CNT		1
-#define CUE_TX_LIST_CNT		1
-
 #define CUE_CTL_READ		0x01
 #define CUE_CTL_WRITE		0x02
 
@@ -143,25 +139,6 @@ struct cue_type {
 	u_int16_t		cue_did;
 };
 
-struct cue_softc;
-
-struct cue_chain {
-	struct cue_softc	*cue_sc;
-	usbd_xfer_handle	cue_xfer;
-	char			*cue_buf;
-	struct mbuf		*cue_mbuf;
-	int			cue_idx;
-};
-
-struct cue_cdata {
-	struct cue_chain	cue_tx_chain[CUE_TX_LIST_CNT];
-	struct cue_chain	cue_rx_chain[CUE_RX_LIST_CNT];
-	int			cue_tx_prod;
-	int			cue_tx_cons;
-	int			cue_tx_cnt;
-	int			cue_rx_prod;
-};
-
 #define CUE_INC(x, y)		(x) = (x + 1) % y
 
 struct cue_softc {
@@ -175,7 +152,7 @@ struct cue_softc {
 	u_int8_t		cue_mctab[CUE_MCAST_TABLE_LEN];
 	int			cue_if_flags;
 	u_int16_t		cue_rxfilt;
-	struct cue_cdata	cue_cdata;
+	struct ue_cdata		cue_cdata;
 	struct callout_handle	cue_stat_ch;
 #if __FreeBSD_version >= 500000
 	struct mtx		cue_mtx;
diff --git a/sys/dev/usb/if_kue.c b/sys/dev/usb/if_kue.c
index 3bc8f4e..307f03a 100644
--- a/sys/dev/usb/if_kue.c
+++ b/sys/dev/usb/if_kue.c
@@ -130,8 +130,6 @@ Static int kue_match(device_ptr_t);
 Static int kue_attach(device_ptr_t);
 Static int kue_detach(device_ptr_t);
 Static void kue_shutdown(device_ptr_t);
-Static int kue_tx_list_init(struct kue_softc *);
-Static int kue_rx_list_init(struct kue_softc *);
 Static int kue_encap(struct kue_softc *, struct mbuf *, int);
 Static void kue_rxeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
 Static void kue_txeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -546,78 +544,29 @@ kue_detach(device_ptr_t dev)
 	return(0);
 }
 
-Static int
-kue_rx_list_init(struct kue_softc *sc)
-{
-	struct kue_cdata	*cd;
-	struct kue_chain	*c;
-	int			i;
-
-	cd = &sc->kue_cdata;
-	for (i = 0; i < KUE_RX_LIST_CNT; i++) {
-		c = &cd->kue_rx_chain[i];
-		c->kue_sc = sc;
-		c->kue_idx = i;
-		c->kue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->kue_dev));
-		if (c->kue_mbuf == NULL)
-			return(ENOBUFS);
-		if (c->kue_xfer == NULL) {
-			c->kue_xfer = usbd_alloc_xfer(sc->kue_udev);
-			if (c->kue_xfer == NULL)
-				return(ENOBUFS);
-		}
-	}
-
-	return(0);
-}
-
-Static int
-kue_tx_list_init(struct kue_softc *sc)
-{
-	struct kue_cdata	*cd;
-	struct kue_chain	*c;
-	int			i;
-
-	cd = &sc->kue_cdata;
-	for (i = 0; i < KUE_TX_LIST_CNT; i++) {
-		c = &cd->kue_tx_chain[i];
-		c->kue_sc = sc;
-		c->kue_idx = i;
-		c->kue_mbuf = NULL;
-		if (c->kue_xfer == NULL) {
-			c->kue_xfer = usbd_alloc_xfer(sc->kue_udev);
-			if (c->kue_xfer == NULL)
-				return(ENOBUFS);
-		}
-		c->kue_buf = malloc(KUE_BUFSZ, M_USBDEV, M_NOWAIT);
-		if (c->kue_buf == NULL)
-			return(ENOBUFS);
-	}
-
-	return(0);
-}
-
 Static void
 kue_rxstart(struct ifnet *ifp)
 {
 	struct kue_softc	*sc;
-	struct kue_chain	*c;
+	struct ue_chain	*c;
 
 	sc = ifp->if_softc;
 	KUE_LOCK(sc);
-	c = &sc->kue_cdata.kue_rx_chain[sc->kue_cdata.kue_rx_prod];
+	c = &sc->kue_cdata.ue_rx_chain[sc->kue_cdata.ue_rx_prod];
 
-	c->kue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->kue_dev));
-	if (c->kue_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->kue_dev));
 		ifp->if_ierrors++;
 		return;
 	}
 
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->kue_xfer, sc->kue_ep[KUE_ENDPT_RX],
-	    c, mtod(c->kue_mbuf, char *), KUE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->kue_ep[KUE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, kue_rxeof);
-	usbd_transfer(c->kue_xfer);
+	usbd_transfer(c->ue_xfer);
 
 	KUE_UNLOCK(sc);
 
@@ -632,14 +581,14 @@ Static void kue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv,
 		      usbd_status status)
 {
 	struct kue_softc	*sc;
-	struct kue_chain	*c;
+	struct ue_chain	*c;
         struct mbuf		*m;
         struct ifnet		*ifp;
 	int			total_len = 0;
 	u_int16_t		len;
 
 	c = priv;
-	sc = c->kue_sc;
+	sc = c->ue_sc;
 	KUE_LOCK(sc);
 	ifp = &sc->arpcom.ac_if;
 
@@ -662,7 +611,7 @@ Static void kue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv,
 	}
 
 	usbd_get_xfer_status(xfer, NULL, NULL, &total_len, NULL);
-	m = c->kue_mbuf;
+	m = c->ue_mbuf;
 	if (total_len <= 1)
 		goto done;
 
@@ -689,10 +638,10 @@ Static void kue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv,
 done:
 
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->kue_xfer, sc->kue_ep[KUE_ENDPT_RX],
-	    c, mtod(c->kue_mbuf, char *), KUE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->kue_ep[KUE_ENDPT_RX],
+	    c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 	    USBD_NO_TIMEOUT, kue_rxeof);
-	usbd_transfer(c->kue_xfer);
+	usbd_transfer(c->ue_xfer);
 	KUE_UNLOCK(sc);
 
 	return;
@@ -707,12 +656,12 @@ Static void
 kue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
 	struct kue_softc	*sc;
-	struct kue_chain	*c;
+	struct ue_chain	*c;
 	struct ifnet		*ifp;
 	usbd_status		err;
 
 	c = priv;
-	sc = c->kue_sc;
+	sc = c->ue_sc;
 	KUE_LOCK(sc);
 
 	ifp = &sc->arpcom.ac_if;
@@ -732,12 +681,12 @@ kue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 		return;
 	}
 
-	usbd_get_xfer_status(c->kue_xfer, NULL, NULL, NULL, &err);
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &err);
 
-	if (c->kue_mbuf != NULL) {
-		c->kue_mbuf->m_pkthdr.rcvif = ifp;
-		usb_tx_done(c->kue_mbuf);
-		c->kue_mbuf = NULL;
+	if (c->ue_mbuf != NULL) {
+		c->ue_mbuf->m_pkthdr.rcvif = ifp;
+		usb_tx_done(c->ue_mbuf);
+		c->ue_mbuf = NULL;
 	}
 
 	if (err)
@@ -754,36 +703,36 @@ Static int
 kue_encap(struct kue_softc *sc, struct mbuf *m, int idx)
 {
 	int			total_len;
-	struct kue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 
-	c = &sc->kue_cdata.kue_tx_chain[idx];
+	c = &sc->kue_cdata.ue_tx_chain[idx];
 
 	/*
 	 * Copy the mbuf data into a contiguous buffer, leaving two
 	 * bytes at the beginning to hold the frame length.
 	 */
-	m_copydata(m, 0, m->m_pkthdr.len, c->kue_buf + 2);
-	c->kue_mbuf = m;
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf + 2);
+	c->ue_mbuf = m;
 
 	total_len = m->m_pkthdr.len + 2;
 	total_len += 64 - (total_len % 64);
 
 	/* Frame length is specified in the first 2 bytes of the buffer. */
-	c->kue_buf[0] = (u_int8_t)m->m_pkthdr.len;
-	c->kue_buf[1] = (u_int8_t)(m->m_pkthdr.len >> 8);
+	c->ue_buf[0] = (u_int8_t)m->m_pkthdr.len;
+	c->ue_buf[1] = (u_int8_t)(m->m_pkthdr.len >> 8);
 
-	usbd_setup_xfer(c->kue_xfer, sc->kue_ep[KUE_ENDPT_TX],
-	    c, c->kue_buf, total_len, 0, 10000, kue_txeof);
+	usbd_setup_xfer(c->ue_xfer, sc->kue_ep[KUE_ENDPT_TX],
+	    c, c->ue_buf, total_len, 0, 10000, kue_txeof);
 
 	/* Transmit */
-	err = usbd_transfer(c->kue_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (err != USBD_IN_PROGRESS) {
 		kue_stop(sc);
 		return(EIO);
 	}
 
-	sc->kue_cdata.kue_tx_cnt++;
+	sc->kue_cdata.ue_tx_cnt++;
 
 	return(0);
 }
@@ -837,7 +786,7 @@ kue_init(void *xsc)
 {
 	struct kue_softc	*sc = xsc;
 	struct ifnet		*ifp = &sc->arpcom.ac_if;
-	struct kue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 	int			i;
 
@@ -871,14 +820,16 @@ kue_init(void *xsc)
 	kue_setword(sc, KUE_CMD_SET_URB_SIZE, 64);
 
 	/* Init TX ring. */
-	if (kue_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->kue_cdata,
+	    USBDEVNAME(sc->kue_dev), sc->kue_udev) == ENOBUFS) {
 		printf("kue%d: tx list init failed\n", sc->kue_unit);
 		KUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Init RX ring. */
-	if (kue_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->kue_cdata,
+	    USBDEVNAME(sc->kue_dev), sc->kue_udev) == ENOBUFS) {
 		printf("kue%d: rx list init failed\n", sc->kue_unit);
 		KUE_UNLOCK(sc);
 		return;
@@ -907,12 +858,12 @@ kue_init(void *xsc)
 	}
 
 	/* Start up the receive pipe. */
-	for (i = 0; i < KUE_RX_LIST_CNT; i++) {
-		c = &sc->kue_cdata.kue_rx_chain[i];
-		usbd_setup_xfer(c->kue_xfer, sc->kue_ep[KUE_ENDPT_RX],
-		    c, mtod(c->kue_mbuf, char *), KUE_BUFSZ,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->kue_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->kue_ep[KUE_ENDPT_RX],
+		    c, mtod(c->ue_mbuf, char *), UE_BUFSZ,
 	    	USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, kue_rxeof);
-		usbd_transfer(c->kue_xfer);
+		usbd_transfer(c->ue_xfer);
 	}
 
 	ifp->if_flags |= IFF_RUNNING;
@@ -974,7 +925,7 @@ Static void
 kue_watchdog(struct ifnet *ifp)
 {
 	struct kue_softc	*sc;
-	struct kue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		stat;
 
 	sc = ifp->if_softc;
@@ -982,9 +933,9 @@ kue_watchdog(struct ifnet *ifp)
 	ifp->if_oerrors++;
 	printf("kue%d: watchdog timeout\n", sc->kue_unit);
 
-	c = &sc->kue_cdata.kue_tx_chain[0];
-	usbd_get_xfer_status(c->kue_xfer, NULL, NULL, NULL, &stat);
-	kue_txeof(c->kue_xfer, c, stat);
+	c = &sc->kue_cdata.ue_tx_chain[0];
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &stat);
+	kue_txeof(c->ue_xfer, c, stat);
 
 	if (ifp->if_snd.ifq_head != NULL)
 		kue_start(ifp);
@@ -1052,36 +1003,9 @@ kue_stop(struct kue_softc *sc)
 	}
 
 	/* Free RX resources. */
-	for (i = 0; i < KUE_RX_LIST_CNT; i++) {
-		if (sc->kue_cdata.kue_rx_chain[i].kue_buf != NULL) {
-			free(sc->kue_cdata.kue_rx_chain[i].kue_buf, M_USBDEV);
-			sc->kue_cdata.kue_rx_chain[i].kue_buf = NULL;
-		}
-		if (sc->kue_cdata.kue_rx_chain[i].kue_mbuf != NULL) {
-			m_freem(sc->kue_cdata.kue_rx_chain[i].kue_mbuf);
-			sc->kue_cdata.kue_rx_chain[i].kue_mbuf = NULL;
-		}
-		if (sc->kue_cdata.kue_rx_chain[i].kue_xfer != NULL) {
-			usbd_free_xfer(sc->kue_cdata.kue_rx_chain[i].kue_xfer);
-			sc->kue_cdata.kue_rx_chain[i].kue_xfer = NULL;
-		}
-	}
-
+	usb_ether_rx_list_free(&sc->kue_cdata);
 	/* Free TX resources. */
-	for (i = 0; i < KUE_TX_LIST_CNT; i++) {
-		if (sc->kue_cdata.kue_tx_chain[i].kue_buf != NULL) {
-			free(sc->kue_cdata.kue_tx_chain[i].kue_buf, M_USBDEV);
-			sc->kue_cdata.kue_tx_chain[i].kue_buf = NULL;
-		}
-		if (sc->kue_cdata.kue_tx_chain[i].kue_mbuf != NULL) {
-			m_freem(sc->kue_cdata.kue_tx_chain[i].kue_mbuf);
-			sc->kue_cdata.kue_tx_chain[i].kue_mbuf = NULL;
-		}
-		if (sc->kue_cdata.kue_tx_chain[i].kue_xfer != NULL) {
-			usbd_free_xfer(sc->kue_cdata.kue_tx_chain[i].kue_xfer);
-			sc->kue_cdata.kue_tx_chain[i].kue_xfer = NULL;
-		}
-	}
+	usb_ether_tx_list_free(&sc->kue_cdata);
 
 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
 	KUE_UNLOCK(sc);
diff --git a/sys/dev/usb/if_kuereg.h b/sys/dev/usb/if_kuereg.h
index 102ccd3..298526d 100644
--- a/sys/dev/usb/if_kuereg.h
+++ b/sys/dev/usb/if_kuereg.h
@@ -110,12 +110,8 @@ struct kue_ether_desc {
 #define KUE_RXFILT_MULTICAST		0x0010
 
 #define KUE_TIMEOUT		1000
-#define KUE_BUFSZ		1536
 #define KUE_MIN_FRAMELEN	60
 
-#define KUE_RX_LIST_CNT		1
-#define KUE_TX_LIST_CNT		1
-
 #define KUE_CTL_READ		0x01
 #define KUE_CTL_WRITE		0x02
 
@@ -136,25 +132,6 @@ struct kue_type {
 	u_int16_t		kue_did;
 };
 
-struct kue_softc;
-
-struct kue_chain {
-	struct kue_softc	*kue_sc;
-	usbd_xfer_handle	kue_xfer;
-	char			*kue_buf;
-	struct mbuf		*kue_mbuf;
-	int			kue_idx;
-};
-
-struct kue_cdata {
-	struct kue_chain	kue_tx_chain[KUE_TX_LIST_CNT];
-	struct kue_chain	kue_rx_chain[KUE_RX_LIST_CNT];
-	int			kue_tx_prod;
-	int			kue_tx_cons;
-	int			kue_tx_cnt;
-	int			kue_rx_prod;
-};
-
 #define KUE_INC(x, y)		(x) = (x + 1) % y
 
 struct kue_softc {
@@ -169,7 +146,7 @@ struct kue_softc {
 	int			kue_if_flags;
 	u_int16_t		kue_rxfilt;
 	u_int8_t		*kue_mcfilters;
-	struct kue_cdata	kue_cdata;
+	struct ue_cdata		kue_cdata;
 #if __FreeBSD_version >= 500000
 	struct mtx		kue_mtx;
 #endif
diff --git a/sys/dev/usb/if_rue.c b/sys/dev/usb/if_rue.c
index a5adaf6..d1bbd7c 100644
--- a/sys/dev/usb/if_rue.c
+++ b/sys/dev/usb/if_rue.c
@@ -132,8 +132,6 @@ Static int rue_match(device_ptr_t);
 Static int rue_attach(device_ptr_t);
 Static int rue_detach(device_ptr_t);
 
-Static int rue_tx_list_init(struct rue_softc *);
-Static int rue_rx_list_init(struct rue_softc *);
 Static int rue_encap(struct rue_softc *, struct mbuf *, int);
 #ifdef RUE_INTR_PIPE
 Static void rue_intr(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -738,57 +736,6 @@ rue_detach(device_ptr_t dev)
 	return (0);
 }
 
-Static int
-rue_rx_list_init(struct rue_softc *sc)
-{
-	struct rue_cdata	*cd;
-	struct rue_chain	*c;
-	int			i;
-
-	cd = &sc->rue_cdata;
-	for (i = 0; i < RUE_RX_LIST_CNT; i++) {
-		c = &cd->rue_rx_chain[i];
-		c->rue_sc = sc;
-		c->rue_idx = i;
-		c->rue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->rue_dev));
-		if (c->rue_mbuf == NULL)
-			return (ENOBUFS);
-		if (c->rue_xfer == NULL) {
-			c->rue_xfer = usbd_alloc_xfer(sc->rue_udev);
-			if (c->rue_xfer == NULL)
-				return (ENOBUFS);
-		}
-	}
-
-	return (0);
-}
-
-Static int
-rue_tx_list_init(struct rue_softc *sc)
-{
-	struct rue_cdata	*cd;
-	struct rue_chain	*c;
-	int			i;
-
-	cd = &sc->rue_cdata;
-	for (i = 0; i < RUE_TX_LIST_CNT; i++) {
-		c = &cd->rue_tx_chain[i];
-		c->rue_sc = sc;
-		c->rue_idx = i;
-		c->rue_mbuf = NULL;
-		if (c->rue_xfer == NULL) {
-			c->rue_xfer = usbd_alloc_xfer(sc->rue_udev);
-			if (c->rue_xfer == NULL)
-				return (ENOBUFS);
-		}
-		c->rue_buf = malloc(RUE_BUFSZ, M_USBDEV, M_NOWAIT);
-		if (c->rue_buf == NULL)
-			return (ENOBUFS);
-	}
-
-	return (0);
-}
-
 #ifdef RUE_INTR_PIPE
 Static void
 rue_intr(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
@@ -832,24 +779,26 @@ Static void
 rue_rxstart(struct ifnet *ifp)
 {
 	struct rue_softc	*sc;
-	struct rue_chain	*c;
+	struct ue_chain	*c;
 
 	sc = ifp->if_softc;
 	RUE_LOCK(sc);
-	c = &sc->rue_cdata.rue_rx_chain[sc->rue_cdata.rue_rx_prod];
+	c = &sc->rue_cdata.ue_rx_chain[sc->rue_cdata.ue_rx_prod];
 
-	c->rue_mbuf = usb_ether_newbuf(USBDEVNAME(sc->rue_dev));
-	if (c->rue_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->rue_dev));
 		ifp->if_ierrors++;
 		RUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Setup new transfer. */
-	usbd_setup_xfer(c->rue_xfer, sc->rue_ep[RUE_ENDPT_RX],
-		c, mtod(c->rue_mbuf, char *), RUE_BUFSZ, USBD_SHORT_XFER_OK,
+	usbd_setup_xfer(c->ue_xfer, sc->rue_ep[RUE_ENDPT_RX],
+		c, mtod(c->ue_mbuf, char *), UE_BUFSZ, USBD_SHORT_XFER_OK,
 		USBD_NO_TIMEOUT, rue_rxeof);
-	usbd_transfer(c->rue_xfer);
+	usbd_transfer(c->ue_xfer);
 
 	RUE_UNLOCK(sc);
 }
@@ -862,8 +811,8 @@ rue_rxstart(struct ifnet *ifp)
 Static void
 rue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct rue_chain	*c = priv;
-	struct rue_softc	*sc = c->rue_sc;
+	struct ue_chain	*c = priv;
+	struct rue_softc	*sc = c->ue_sc;
 	struct mbuf		*m;
 	struct ifnet		*ifp;
 	int			total_len = 0;
@@ -899,7 +848,7 @@ rue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 		goto done;
 	}
 
-	m = c->rue_mbuf;
+	m = c->ue_mbuf;
 	bcopy(mtod(m, char *) + total_len - 4, (char *)&r, sizeof (r));
 
 	/* Check recieve packet was valid or not */
@@ -924,7 +873,7 @@ rue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
     done:
 	/* Setup new transfer. */
 	usbd_setup_xfer(xfer, sc->rue_ep[RUE_ENDPT_RX],
-			c, mtod(c->rue_mbuf, char *), RUE_BUFSZ,
+			c, mtod(c->ue_mbuf, char *), UE_BUFSZ,
 			USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, rue_rxeof);
 	usbd_transfer(xfer);
 	RUE_UNLOCK(sc);
@@ -938,8 +887,8 @@ rue_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 Static void
 rue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct rue_chain	*c = priv;
-	struct rue_softc	*sc = c->rue_sc;
+	struct ue_chain	*c = priv;
+	struct rue_softc	*sc = c->ue_sc;
 	struct ifnet		*ifp;
 	usbd_status		err;
 
@@ -962,12 +911,12 @@ rue_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	ifp->if_timer = 0;
 	ifp->if_flags &= ~IFF_OACTIVE;
-	usbd_get_xfer_status(c->rue_xfer, NULL, NULL, NULL, &err);
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &err);
 
-	if (c->rue_mbuf != NULL) {
-		c->rue_mbuf->m_pkthdr.rcvif = ifp;
-		usb_tx_done(c->rue_mbuf);
-		c->rue_mbuf = NULL;
+	if (c->ue_mbuf != NULL) {
+		c->ue_mbuf->m_pkthdr.rcvif = ifp;
+		usb_tx_done(c->ue_mbuf);
+		c->ue_mbuf = NULL;
 	}
 
 	if (err)
@@ -1014,16 +963,16 @@ Static int
 rue_encap(struct rue_softc *sc, struct mbuf *m, int idx)
 {
 	int			total_len;
-	struct rue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 
-	c = &sc->rue_cdata.rue_tx_chain[idx];
+	c = &sc->rue_cdata.ue_tx_chain[idx];
 
 	/*
 	 * Copy the mbuf data into a contiguous buffer
 	 */
-	m_copydata(m, 0, m->m_pkthdr.len, c->rue_buf);
-	c->rue_mbuf = m;
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf);
+	c->ue_mbuf = m;
 
 	total_len = m->m_pkthdr.len;
 
@@ -1035,18 +984,18 @@ rue_encap(struct rue_softc *sc, struct mbuf *m, int idx)
 	if (total_len < RUE_MIN_FRAMELEN)
 		total_len = RUE_MIN_FRAMELEN;
 
-	usbd_setup_xfer(c->rue_xfer, sc->rue_ep[RUE_ENDPT_TX],
-			c, c->rue_buf, total_len, USBD_FORCE_SHORT_XFER,
+	usbd_setup_xfer(c->ue_xfer, sc->rue_ep[RUE_ENDPT_TX],
+			c, c->ue_buf, total_len, USBD_FORCE_SHORT_XFER,
 			10000, rue_txeof);
 
 	/* Transmit */
-	err = usbd_transfer(c->rue_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (err != USBD_IN_PROGRESS) {
 		rue_stop(sc);
 		return (EIO);
 	}
 
-	sc->rue_cdata.rue_tx_cnt++;
+	sc->rue_cdata.ue_tx_cnt++;
 
 	return (0);
 }
@@ -1104,7 +1053,7 @@ rue_init(void *xsc)
 	struct rue_softc	*sc = xsc;
 	struct ifnet		*ifp = &sc->arpcom.ac_if;
 	struct mii_data		*mii = GET_MII(sc);
-	struct rue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		err;
 	int			i;
 	int			rxcfg;
@@ -1125,21 +1074,23 @@ rue_init(void *xsc)
 	rue_write_mem(sc, RUE_IDR0, sc->arpcom.ac_enaddr, ETHER_ADDR_LEN);
 
 	/* Init TX ring. */
-	if (rue_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->rue_cdata,
+	    USBDEVNAME(sc->rue_dev), sc->rue_udev) == ENOBUFS) {
 		printf("rue%d: tx list init failed\n", sc->rue_unit);
 		RUE_UNLOCK(sc);
 		return;
 	}
 
 	/* Init RX ring. */
-	if (rue_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->rue_cdata,
+	    USBDEVNAME(sc->rue_dev), sc->rue_udev) == ENOBUFS) {
 		printf("rue%d: rx list init failed\n", sc->rue_unit);
 		RUE_UNLOCK(sc);
 		return;
 	}
 
 #ifdef RUE_INTR_PIPE
-	sc->rue_cdata.rue_ibuf = malloc(RUE_INTR_PKTLEN, M_USBDEV, M_NOWAIT);
+	sc->rue_cdata.ue_ibuf = malloc(RUE_INTR_PKTLEN, M_USBDEV, M_NOWAIT);
 #endif
 
 	/*
@@ -1193,7 +1144,7 @@ rue_init(void *xsc)
 	err = usbd_open_pipe_intr(sc->rue_iface, sc->rue_ed[RUE_ENDPT_INTR],
 				  USBD_SHORT_XFER_OK,
 				  &sc->rue_ep[RUE_ENDPT_INTR], sc,
-				  sc->rue_cdata.rue_ibuf, RUE_INTR_PKTLEN,
+				  sc->rue_cdata.ue_ibuf, RUE_INTR_PKTLEN,
 				  rue_intr, RUE_INTR_INTERVAL);
 	if (err) {
 		printf("rue%d: open intr pipe failed: %s\n",
@@ -1204,12 +1155,12 @@ rue_init(void *xsc)
 #endif
 
 	/* Start up the receive pipe. */
-	for (i = 0; i < RUE_RX_LIST_CNT; i++) {
-		c = &sc->rue_cdata.rue_rx_chain[i];
-		usbd_setup_xfer(c->rue_xfer, sc->rue_ep[RUE_ENDPT_RX],
-				c, mtod(c->rue_mbuf, char *), RUE_BUFSZ,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->rue_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->rue_ep[RUE_ENDPT_RX],
+				c, mtod(c->ue_mbuf, char *), UE_BUFSZ,
 				USBD_SHORT_XFER_OK, USBD_NO_TIMEOUT, rue_rxeof);
-		usbd_transfer(c->rue_xfer);
+		usbd_transfer(c->ue_xfer);
 	}
 
 	ifp->if_flags |= IFF_RUNNING;
@@ -1314,7 +1265,7 @@ Static void
 rue_watchdog(struct ifnet *ifp)
 {
 	struct rue_softc	*sc = ifp->if_softc;
-	struct rue_chain	*c;
+	struct ue_chain	*c;
 	usbd_status		stat;
 
 	RUE_LOCK(sc);
@@ -1322,9 +1273,9 @@ rue_watchdog(struct ifnet *ifp)
 	ifp->if_oerrors++;
 	printf("rue%d: watchdog timeout\n", sc->rue_unit);
 
-	c = &sc->rue_cdata.rue_tx_chain[0];
-	usbd_get_xfer_status(c->rue_xfer, NULL, NULL, NULL, &stat);
-	rue_txeof(c->rue_xfer, c, stat);
+	c = &sc->rue_cdata.ue_tx_chain[0];
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &stat);
+	rue_txeof(c->ue_xfer, c, stat);
 
 	if (ifp->if_snd.ifq_head != NULL)
 		rue_start(ifp);
@@ -1400,40 +1351,13 @@ rue_stop(struct rue_softc *sc)
 #endif
 
 	/* Free RX resources. */
-	for (i = 0; i < RUE_RX_LIST_CNT; i++) {
-		if (sc->rue_cdata.rue_rx_chain[i].rue_buf != NULL) {
-			free(sc->rue_cdata.rue_rx_chain[i].rue_buf, M_USBDEV);
-			sc->rue_cdata.rue_rx_chain[i].rue_buf = NULL;
-		}
-		if (sc->rue_cdata.rue_rx_chain[i].rue_mbuf != NULL) {
-			m_freem(sc->rue_cdata.rue_rx_chain[i].rue_mbuf);
-			sc->rue_cdata.rue_rx_chain[i].rue_mbuf = NULL;
-		}
-		if (sc->rue_cdata.rue_rx_chain[i].rue_xfer != NULL) {
-			usbd_free_xfer(sc->rue_cdata.rue_rx_chain[i].rue_xfer);
-			sc->rue_cdata.rue_rx_chain[i].rue_xfer = NULL;
-		}
-	}
-
+	usb_ether_rx_list_free(&sc->rue_cdata);
 	/* Free TX resources. */
-	for (i = 0; i < RUE_TX_LIST_CNT; i++) {
-		if (sc->rue_cdata.rue_tx_chain[i].rue_buf != NULL) {
-			free(sc->rue_cdata.rue_tx_chain[i].rue_buf, M_USBDEV);
-			sc->rue_cdata.rue_tx_chain[i].rue_buf = NULL;
-		}
-		if (sc->rue_cdata.rue_tx_chain[i].rue_mbuf != NULL) {
-			m_freem(sc->rue_cdata.rue_tx_chain[i].rue_mbuf);
-			sc->rue_cdata.rue_tx_chain[i].rue_mbuf = NULL;
-		}
-		if (sc->rue_cdata.rue_tx_chain[i].rue_xfer != NULL) {
-			usbd_free_xfer(sc->rue_cdata.rue_tx_chain[i].rue_xfer);
-			sc->rue_cdata.rue_tx_chain[i].rue_xfer = NULL;
-		}
-	}
+	usb_ether_tx_list_free(&sc->rue_cdata);
 
 #ifdef RUE_INTR_PIPE
-	free(sc->rue_cdata.rue_ibuf, M_USBDEV);
-	sc->rue_cdata.rue_ibuf = NULL;
+	free(sc->rue_cdata.ue_ibuf, M_USBDEV);
+	sc->rue_cdata.ue_ibuf = NULL;
 #endif
 
 	sc->rue_link = 0;
diff --git a/sys/dev/usb/if_ruereg.h b/sys/dev/usb/if_ruereg.h
index df87687..206cc7e 100644
--- a/sys/dev/usb/if_ruereg.h
+++ b/sys/dev/usb/if_ruereg.h
@@ -43,7 +43,6 @@
 
 #define RUE_TIMEOUT		1000
 #define	ETHER_ALIGN		2
-#define RUE_BUFSZ		1536
 #define RUE_MIN_FRAMELEN	60
 #define	RUE_INTR_INTERVAL	100	/* ms */
 
@@ -187,29 +186,6 @@ struct rue_type {
 	u_int16_t		rue_did;
 };
 
-#define RUE_TX_LIST_CNT		1
-#define RUE_RX_LIST_CNT		1
-
-struct rue_softc;
-
-struct rue_chain {
-	struct rue_softc	*rue_sc;
-	usbd_xfer_handle	rue_xfer;
-	char			*rue_buf;
-	struct mbuf		*rue_mbuf;
-	int			rue_idx;
-};
-
-struct rue_cdata {
-	struct rue_chain	rue_tx_chain[RUE_TX_LIST_CNT];
-	struct rue_chain	rue_rx_chain[RUE_RX_LIST_CNT];
-	struct rue_intrpkt	*rue_ibuf;
-	int			rue_tx_prod;
-	int			rue_tx_cons;
-	int			rue_tx_cnt;
-	int			rue_rx_prod;
-};
-
 struct rue_softc {
 	struct arpcom		arpcom;
 	device_t		rue_dev;
@@ -222,7 +198,7 @@ struct rue_softc {
 	int			rue_unit;
 	u_int8_t		rue_link;
 	int			rue_if_flags;
-	struct rue_cdata	rue_cdata;
+	struct ue_cdata		rue_cdata;
 	struct callout_handle	rue_stat_ch;
 #if __FreeBSD_version >= 500000
 	struct mtx		rue_mtx;
diff --git a/sys/dev/usb/if_udav.c b/sys/dev/usb/if_udav.c
index 93180a1..32f8164 100644
--- a/sys/dev/usb/if_udav.c
+++ b/sys/dev/usb/if_udav.c
@@ -159,8 +159,6 @@ Static void udav_shutdown(device_ptr_t);
 #endif
 
 Static int udav_openpipes(struct udav_softc *);
-Static int udav_rx_list_init(struct udav_softc *);
-Static int udav_tx_list_init(struct udav_softc *);
 Static void udav_start(struct ifnet *);
 Static int udav_send(struct udav_softc *, struct mbuf *, int);
 Static void udav_txeof(usbd_xfer_handle, usbd_private_handle, usbd_status);
@@ -856,7 +854,8 @@ udav_init(void *xsc)
 		UDAV_CLRBIT(sc, UDAV_RCR, UDAV_RCR_ALL|UDAV_RCR_PRMSC);
 
 	/* Initialize transmit ring */
-	if (udav_tx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_tx_list_init(sc, &sc->sc_cdata,
+	    USBDEVNAME(sc->sc_dev), sc->sc_udev) == ENOBUFS) {
 		printf("%s: tx list init failed\n", USBDEVNAME(sc->sc_dev));
 #if defined(__NetBSD__)
 		splx(s);
@@ -869,7 +868,8 @@ udav_init(void *xsc)
 	}
 
 	/* Initialize receive ring */
-	if (udav_rx_list_init(sc) == ENOBUFS) {
+	if (usb_ether_rx_list_init(sc, &sc->sc_cdata,
+	    USBDEVNAME(sc->sc_dev), sc->sc_udev) == ENOBUFS) {
 		printf("%s: rx list init failed\n", USBDEVNAME(sc->sc_dev));
 #if defined(__NetBSD__)
 		splx(s);
@@ -1060,7 +1060,7 @@ udav_setmulti(struct udav_softc *sc)
 Static int
 udav_openpipes(struct udav_softc *sc)
 {
-	struct udav_chain *c;
+	struct ue_chain *c;
 	usbd_status err;
 	int i;
 	int error = 0;
@@ -1095,7 +1095,7 @@ udav_openpipes(struct udav_softc *sc)
 	/* Open Interrupt pipe */
 	err = usbd_open_pipe_intr(sc->sc_ctl_iface, sc->sc_intrin_no,
 				  USBD_EXCLUSIVE_USE, &sc->sc_pipe_intr, sc,
-				  &sc->sc_cdata.udav_ibuf, UDAV_INTR_PKGLEN,
+				  &sc->sc_cdata.ue_ibuf, UDAV_INTR_PKGLEN,
 				  udav_intr, UDAV_INTR_INTERVAL);
 	if (err) {
 		printf("%s: open intr pipe failed: %s\n",
@@ -1107,13 +1107,13 @@ udav_openpipes(struct udav_softc *sc)
 
 
 	/* Start up the receive pipe. */
-	for (i = 0; i < UDAV_RX_LIST_CNT; i++) {
-		c = &sc->sc_cdata.udav_rx_chain[i];
-		usbd_setup_xfer(c->udav_xfer, sc->sc_pipe_rx,
-				c, c->udav_buf, UDAV_BUFSZ,
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &sc->sc_cdata.ue_rx_chain[i];
+		usbd_setup_xfer(c->ue_xfer, sc->sc_pipe_rx,
+				c, c->ue_buf, UE_BUFSZ,
 				USBD_SHORT_XFER_OK | USBD_NO_COPY,
 				USBD_NO_TIMEOUT, udav_rxeof);
-		(void)usbd_transfer(c->udav_xfer);
+		(void)usbd_transfer(c->ue_xfer);
 		DPRINTF(("%s: %s: start read\n", USBDEVNAME(sc->sc_dev),
 			 __func__));
 	}
@@ -1125,68 +1125,6 @@ udav_openpipes(struct udav_softc *sc)
 	return (error);
 }
 
-Static int
-udav_rx_list_init(struct udav_softc *sc)
-{
-	struct udav_cdata *cd;
-	struct udav_chain *c;
-	int i;
-
-	DPRINTF(("%s: %s: enter\n", USBDEVNAME(sc->sc_dev), __func__));
-
-	cd = &sc->sc_cdata;
-	for (i = 0; i < UDAV_RX_LIST_CNT; i++) {
-		c = &cd->udav_rx_chain[i];
-		c->udav_sc = sc;
-		c->udav_idx = i;
-		c->udav_mbuf = usb_ether_newbuf(USBDEVNAME(sc->sc_dev));
-		if (c->udav_mbuf == NULL)
-			return (ENOBUFS);
-		if (c->udav_xfer == NULL) {
-			c->udav_xfer = usbd_alloc_xfer(sc->sc_udev);
-			if (c->udav_xfer == NULL)
-				return (ENOBUFS);
-			c->udav_buf = usbd_alloc_buffer(c->udav_xfer, UDAV_BUFSZ);
-			if (c->udav_buf == NULL) {
-				usbd_free_xfer(c->udav_xfer);
-				return (ENOBUFS);
-			}
-		}
-	}
-
-	return (0);
-}
-
-Static int
-udav_tx_list_init(struct udav_softc *sc)
-{
-	struct udav_cdata *cd;
-	struct udav_chain *c;
-	int i;
-
-	DPRINTF(("%s: %s: enter\n", USBDEVNAME(sc->sc_dev), __func__));
-
-	cd = &sc->sc_cdata;
-	for (i = 0; i < UDAV_TX_LIST_CNT; i++) {
-		c = &cd->udav_tx_chain[i];
-		c->udav_sc = sc;
-		c->udav_idx = i;
-		c->udav_mbuf = NULL;
-		if (c->udav_xfer == NULL) {
-			c->udav_xfer = usbd_alloc_xfer(sc->sc_udev);
-			if (c->udav_xfer == NULL)
-				return (ENOBUFS);
-			c->udav_buf = usbd_alloc_buffer(c->udav_xfer, UDAV_BUFSZ);
-			if (c->udav_buf == NULL) {
-				usbd_free_xfer(c->udav_xfer);
-				return (ENOBUFS);
-			}
-		}
-	}
-
-	return (0);
-}
-
 Static void
 udav_start(struct ifnet *ifp)
 {
@@ -1238,36 +1176,36 @@ Static int
 udav_send(struct udav_softc *sc, struct mbuf *m, int idx)
 {
 	int total_len;
-	struct udav_chain *c;
+	struct ue_chain *c;
 	usbd_status err;
 
 	DPRINTF(("%s: %s: enter\n", USBDEVNAME(sc->sc_dev),__func__));
 
-	c = &sc->sc_cdata.udav_tx_chain[idx];
+	c = &sc->sc_cdata.ue_tx_chain[idx];
 
 	/* Copy the mbuf data into a contiguous buffer */
 	/*  first 2 bytes are packet length */
-	m_copydata(m, 0, m->m_pkthdr.len, c->udav_buf + 2);
-	c->udav_mbuf = m;
+	m_copydata(m, 0, m->m_pkthdr.len, c->ue_buf + 2);
+	c->ue_mbuf = m;
 	total_len = m->m_pkthdr.len;
 	if (total_len < UDAV_MIN_FRAME_LEN) {
-		memset(c->udav_buf + 2 + total_len, 0,
+		memset(c->ue_buf + 2 + total_len, 0,
 		    UDAV_MIN_FRAME_LEN - total_len);
 		total_len = UDAV_MIN_FRAME_LEN;
 	}
 
 	/* Frame length is specified in the first 2bytes of the buffer */
-	c->udav_buf[0] = (u_int8_t)total_len;
-	c->udav_buf[1] = (u_int8_t)(total_len >> 8);
+	c->ue_buf[0] = (u_int8_t)total_len;
+	c->ue_buf[1] = (u_int8_t)(total_len >> 8);
 	total_len += 2;
 
-	usbd_setup_xfer(c->udav_xfer, sc->sc_pipe_tx, c, c->udav_buf, total_len,
+	usbd_setup_xfer(c->ue_xfer, sc->sc_pipe_tx, c, c->ue_buf, total_len,
 			USBD_FORCE_SHORT_XFER | USBD_NO_COPY,
 			UDAV_TX_TIMEOUT, udav_txeof);
 
 	/* Transmit */
 	sc->sc_refcnt++;
-	err = usbd_transfer(c->udav_xfer);
+	err = usbd_transfer(c->ue_xfer);
 	if (--sc->sc_refcnt < 0)
 		usb_detach_wakeup(USBDEV(sc->sc_dev));
 	if (err != USBD_IN_PROGRESS) {
@@ -1281,7 +1219,7 @@ udav_send(struct udav_softc *sc, struct mbuf *m, int idx)
 	DPRINTF(("%s: %s: send %d bytes\n", USBDEVNAME(sc->sc_dev),
 		 __func__, total_len));
 
-	sc->sc_cdata.udav_tx_cnt++;
+	sc->sc_cdata.ue_tx_cnt++;
 
 	return (0);
 }
@@ -1289,8 +1227,8 @@ udav_send(struct udav_softc *sc, struct mbuf *m, int idx)
 Static void
 udav_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct udav_chain *c = priv;
-	struct udav_softc *sc = c->udav_sc;
+	struct ue_chain *c = priv;
+	struct udav_softc *sc = c->ue_sc;
 	struct ifnet *ifp = GET_IFP(sc);
 #if defined(__NetBSD__)
 	int s;
@@ -1338,8 +1276,8 @@ udav_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 
 	ifp->if_opackets++;
 
-	m_freem(c->udav_mbuf);
-	c->udav_mbuf = NULL;
+	m_freem(c->ue_mbuf);
+	c->ue_mbuf = NULL;
 
 #if defined(__NetBSD__)
 	if (IFQ_IS_EMPTY(&ifp->if_snd) == 0)
@@ -1358,8 +1296,8 @@ udav_txeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 Static void
 udav_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 {
-	struct udav_chain *c = priv;
-	struct udav_softc *sc = c->udav_sc;
+	struct ue_chain *c = priv;
+	struct udav_softc *sc = c->ue_sc;
 	struct ifnet *ifp = GET_IFP(sc);
 	struct mbuf *m;
 	u_int32_t total_len;
@@ -1395,8 +1333,8 @@ udav_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 	usbd_get_xfer_status(xfer, NULL, NULL, &total_len, NULL);
 
 	/* copy data to mbuf */
-	m = c->udav_mbuf;
-	memcpy(mtod(m, char *), c->udav_buf, total_len);
+	m = c->ue_mbuf;
+	memcpy(mtod(m, char *), c->ue_buf, total_len);
 
 	/* first byte in received data */
 	pktstat = mtod(m, u_int8_t *);
@@ -1434,8 +1372,10 @@ udav_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 #endif
 
 #if defined(__NetBSD__)
-	c->udav_mbuf = usb_ether_newbuf(USBDEVNAME(sc->sc_dev));
-	if (c->udav_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->sc_dev));
 		ifp->if_ierrors++;
 		goto done1;
 	}
@@ -1464,7 +1404,7 @@ udav_rxeof(usbd_xfer_handle xfer, usbd_private_handle priv, usbd_status status)
 #endif
  done:
 	/* Setup new transfer */
-	usbd_setup_xfer(xfer, sc->sc_pipe_rx, c, c->udav_buf, UDAV_BUFSZ,
+	usbd_setup_xfer(xfer, sc->sc_pipe_rx, c, c->ue_buf, UE_BUFSZ,
 			USBD_SHORT_XFER_OK | USBD_NO_COPY,
 			USBD_NO_TIMEOUT, udav_rxeof);
 	sc->sc_refcnt++;
@@ -1563,7 +1503,7 @@ Static void
 udav_watchdog(struct ifnet *ifp)
 {
 	struct udav_softc *sc = ifp->if_softc;
-	struct udav_chain *c;
+	struct ue_chain *c;
 	usbd_status stat;
 #if defined(__NetBSD__)
 	int s;
@@ -1579,9 +1519,9 @@ udav_watchdog(struct ifnet *ifp)
 #elif defined(__FreeBSD__)
         UDAV_LOCK(sc)
 #endif
-	c = &sc->sc_cdata.udav_tx_chain[0];
-	usbd_get_xfer_status(c->udav_xfer, NULL, NULL, NULL, &stat);
-	udav_txeof(c->udav_xfer, c, stat);
+	c = &sc->sc_cdata.ue_tx_chain[0];
+	usbd_get_xfer_status(c->ue_xfer, NULL, NULL, NULL, &stat);
+	udav_txeof(c->ue_xfer, c, stat);
 
 #if defined(__NetBSD__)
 	if (IFQ_IS_EMPTY(&ifp->if_snd) == 0)
@@ -1662,28 +1602,9 @@ udav_stop(struct ifnet *ifp, int disable)
 #endif
 
 	/* Free RX resources. */
-	for (i = 0; i < UDAV_RX_LIST_CNT; i++) {
-		if (sc->sc_cdata.udav_rx_chain[i].udav_mbuf != NULL) {
-			m_freem(sc->sc_cdata.udav_rx_chain[i].udav_mbuf);
-			sc->sc_cdata.udav_rx_chain[i].udav_mbuf = NULL;
-		}
-		if (sc->sc_cdata.udav_rx_chain[i].udav_xfer != NULL) {
-			usbd_free_xfer(sc->sc_cdata.udav_rx_chain[i].udav_xfer);
-			sc->sc_cdata.udav_rx_chain[i].udav_xfer = NULL;
-		}
-	}
-
+	usb_ether_rx_list_free(&sc->sc_cdata);
 	/* Free TX resources. */
-	for (i = 0; i < UDAV_TX_LIST_CNT; i++) {
-		if (sc->sc_cdata.udav_tx_chain[i].udav_mbuf != NULL) {
-			m_freem(sc->sc_cdata.udav_tx_chain[i].udav_mbuf);
-			sc->sc_cdata.udav_tx_chain[i].udav_mbuf = NULL;
-		}
-		if (sc->sc_cdata.udav_tx_chain[i].udav_xfer != NULL) {
-			usbd_free_xfer(sc->sc_cdata.udav_tx_chain[i].udav_xfer);
-			sc->sc_cdata.udav_tx_chain[i].udav_xfer = NULL;
-		}
-	}
+	usb_ether_tx_list_free(&sc->sc_cdata);
 
 	sc->sc_link = 0;
 	ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
@@ -1986,25 +1907,27 @@ Static void
 udav_rxstart(struct ifnet *ifp)
 {
 	struct udav_softc	*sc;
-	struct udav_chain	*c;
+	struct ue_chain	*c;
 
 	sc = ifp->if_softc;
 	UDAV_LOCK(sc);
-	c = &sc->sc_cdata.udav_rx_chain[sc->sc_cdata.udav_rx_prod];
+	c = &sc->sc_cdata.ue_rx_chain[sc->sc_cdata.ue_rx_prod];
 
-	c->udav_mbuf = usb_ether_newbuf(USBDEVNAME(sc->sc_dev));
-	if (c->udav_mbuf == NULL) {
+	c->ue_mbuf = usb_ether_newbuf();
+	if (c->ue_mbuf == NULL) {
+		printf("%s: no memory for rx list "
+		    "-- packet dropped!\n", USBDEVNAME(sc->sc_dev));
 		ifp->if_ierrors++;
 		UDAV_UNLOCK(sc);
 		return;
 	}
 
 	/* Setup new transfer. */
-        usbd_setup_xfer(c->udav_xfer, sc->sc_pipe_rx,
-                        c, c->udav_buf, UDAV_BUFSZ,
+        usbd_setup_xfer(c->ue_xfer, sc->sc_pipe_rx,
+                        c, c->ue_buf, UE_BUFSZ,
                         USBD_SHORT_XFER_OK | USBD_NO_COPY,
                         USBD_NO_TIMEOUT, udav_rxeof);
-	usbd_transfer(c->udav_xfer);
+	usbd_transfer(c->ue_xfer);
 
 	UDAV_UNLOCK(sc);
 	return;
diff --git a/sys/dev/usb/if_udavreg.h b/sys/dev/usb/if_udavreg.h
index 965cbdc..404c9cb 100644
--- a/sys/dev/usb/if_udavreg.h
+++ b/sys/dev/usb/if_udavreg.h
@@ -34,9 +34,6 @@
 #define	UDAV_IFACE_INDEX	0
 #define	UDAV_CONFIG_NO		1
 
-#define	UDAV_TX_LIST_CNT	1
-#define	UDAV_RX_LIST_CNT	1
-
 #define	UDAV_TX_TIMEOUT		1000
 #define	UDAV_TIMEOUT		10000
 
@@ -44,9 +41,7 @@
 
 
 /* Packet length */
-#define	UDAV_MAX_MTU		1536 /* XXX: max frame size is unknown */
 #define	UDAV_MIN_FRAME_LEN	60
-#define	UDAV_BUFSZ		UDAV_MAX_MTU
 
 /* Request */
 #define	UDAV_REQ_REG_READ	0x00 /* Read from register(s) */
@@ -163,27 +158,6 @@
 #endif
 #endif
 
-struct udav_chain {
-	struct udav_softc	*udav_sc;
-	usbd_xfer_handle	udav_xfer;
-	char			*udav_buf;
-	struct mbuf		*udav_mbuf;
-	int			udav_idx;
-};
-
-struct udav_cdata {
-	struct udav_chain	udav_tx_chain[UDAV_TX_LIST_CNT];
-	struct udav_chain	udav_rx_chain[UDAV_TX_LIST_CNT];
-#if 0
-	/* XXX: Intrrupt Endpoint is not yet supported! */
-	struct udav_intrpkg	udav_ibuf;
-#endif
-	int			udav_tx_prod;
-	int			udav_tx_cons;
-	int			udav_tx_cnt;
-	int			udav_rx_prod;
-};
-
 struct udav_softc {
 #if defined(__FreeBSD__)
 	struct arpcom		sc_ac ; /* struct ifnet must be top of softc */
@@ -221,7 +195,7 @@ struct udav_softc {
 #if NRND > 0
 	rndsource_element_t	rnd_source;
 #endif
-	struct udav_cdata	sc_cdata;
+	struct ue_cdata		sc_cdata;
 
 	int                     sc_attached;
 	int			sc_dying;
diff --git a/sys/dev/usb/usb_ethersubr.c b/sys/dev/usb/usb_ethersubr.c
index bccc7ea..90eff91 100644
--- a/sys/dev/usb/usb_ethersubr.c
+++ b/sys/dev/usb/usb_ethersubr.c
@@ -144,18 +144,101 @@ void usb_tx_done(m)
 }
 
 struct mbuf *
-usb_ether_newbuf(const char *devname)
+usb_ether_newbuf(void)
 {
 	struct mbuf *m_new;
 
 	m_new = m_getcl(M_DONTWAIT, MT_DATA, M_PKTHDR);
-	if (m_new == NULL) {
-		printf("%s: no memory for rx list "
-		    "-- packet dropped!\n", devname);
+	if (m_new == NULL)
 		return (NULL);
-	}
 	m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
 
 	m_adj(m_new, ETHER_ALIGN);
 	return (m_new);
 }
+
+int
+usb_ether_rx_list_init(void *sc, struct ue_cdata *cd,
+    usbd_device_handle ue_udev)
+{
+	struct ue_chain *c;
+	int i;
+
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		c = &cd->ue_rx_chain[i];
+		c->ue_sc = sc;
+		c->ue_idx = i;
+		c->ue_mbuf = usb_ether_newbuf();
+		if (c->ue_mbuf == NULL)
+			return (ENOBUFS);
+		if (c->ue_xfer == NULL) {
+			c->ue_xfer = usbd_alloc_xfer(ue_udev);
+			if (c->ue_xfer == NULL)
+				return (ENOBUFS);
+			c->ue_buf = usbd_alloc_buffer(c->ue_xfer, UE_BUFSZ);
+			if (c->ue_buf == NULL)
+				return (ENOBUFS);
+		}
+	}
+
+	return (0);
+}
+
+int
+usb_ether_tx_list_init(void *sc, struct ue_cdata *cd,
+    usbd_device_handle ue_udev)
+{
+	struct ue_chain *c;
+	int i;
+
+	for (i = 0; i < UE_TX_LIST_CNT; i++) {
+		c = &cd->ue_tx_chain[i];
+		c->ue_sc = sc;
+		c->ue_idx = i;
+		c->ue_mbuf = NULL;
+		if (c->ue_xfer == NULL) {
+			c->ue_xfer = usbd_alloc_xfer(ue_udev);
+			if (c->ue_xfer == NULL)
+				return (ENOBUFS);
+			c->ue_buf = usbd_alloc_buffer(c->ue_xfer, UE_BUFSZ);
+			if (c->ue_buf == NULL)
+				return (ENOBUFS);
+		}
+	}
+
+	return (0);
+}
+
+void
+usb_ether_rx_list_free(struct ue_cdata *cd)
+{
+	int i;
+
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		if (cd->ue_rx_chain[i].ue_mbuf != NULL) {
+			m_freem(cd->ue_rx_chain[i].ue_mbuf);
+			cd->ue_rx_chain[i].ue_mbuf = NULL;
+		}
+		if (cd->ue_rx_chain[i].ue_xfer != NULL) {
+			usbd_free_xfer(cd->ue_rx_chain[i].ue_xfer);
+			cd->ue_rx_chain[i].ue_xfer = NULL;
+		}
+	}
+}
+
+void
+usb_ether_tx_list_free(struct ue_cdata *cd)
+{
+	int i;
+
+	for (i = 0; i < UE_RX_LIST_CNT; i++) {
+		if (cd->ue_tx_chain[i].ue_mbuf != NULL) {
+			m_freem(cd->ue_tx_chain[i].ue_mbuf);
+			cd->ue_tx_chain[i].ue_mbuf = NULL;
+		}
+		if (cd->ue_tx_chain[i].ue_xfer != NULL) {
+			usbd_free_xfer(cd->ue_tx_chain[i].ue_xfer);
+			cd->ue_tx_chain[i].ue_xfer = NULL;
+		}
+	}
+}
diff --git a/sys/dev/usb/usb_ethersubr.h b/sys/dev/usb/usb_ethersubr.h
index e53d02e..e3176c5 100644
--- a/sys/dev/usb/usb_ethersubr.h
+++ b/sys/dev/usb/usb_ethersubr.h
@@ -35,14 +35,47 @@
 #ifndef _USB_ETHERSUBR_H_
 #define _USB_ETHERSUBR_H_
 
+#include <sys/bus.h>
+#include <sys/module.h>
+
+#include <dev/usb/usbdi.h>
+
+#define UE_TX_LIST_CNT		1
+#define UE_RX_LIST_CNT		1
+#define UE_BUFSZ		1536
+
 struct usb_qdat {
 	struct ifnet		*ifp;
 	void (*if_rxstart)	(struct ifnet *);
 };
 
+struct ue_chain {
+	void			*ue_sc;
+	usbd_xfer_handle	ue_xfer;
+	char			*ue_buf;
+	struct mbuf		*ue_mbuf;
+	int			ue_idx;
+};
+
+struct ue_cdata {
+	struct ue_chain		ue_tx_chain[UE_TX_LIST_CNT];
+	struct ue_chain		ue_rx_chain[UE_RX_LIST_CNT];
+	void			*ue_ibuf;
+	int			ue_tx_prod;
+	int			ue_tx_cons;
+	int			ue_tx_cnt;
+	int			ue_rx_prod;
+};
+
 void usb_register_netisr	(void);
 void usb_ether_input		(struct mbuf *);
 void usb_tx_done		(struct mbuf *);
-struct mbuf *usb_ether_newbuf	(const char *);
+struct mbuf *usb_ether_newbuf	(void);
+int usb_ether_rx_list_init	(void *, struct ue_cdata *,
+    usbd_device_handle);
+int usb_ether_tx_list_init	(void *, struct ue_cdata *,
+    usbd_device_handle);
+void usb_ether_rx_list_free	(struct ue_cdata *);
+void usb_ether_tx_list_free	(struct ue_cdata *);
 
 #endif