create netif directory

[unix-history] / usr / src / sys / vax / if / if_en.c

diff --git a/usr/src/sys/vax/if/if_en.c b/usr/src/sys/vax/if/if_en.c
index a707279..6299fcb 100644 (file)
--- a/usr/src/sys/vax/if/if_en.c
+++ b/usr/src/sys/vax/if/if_en.c
@@ -1,4 +1,4 @@
-/*     if_en.c 4.32    82/02/03        */
+/*     if_en.c 4.71    82/10/24        */

 
 #include "en.h"
 
 
 #include "en.h"
 


@@ -13,21 +13,28 @@
 #include "../h/buf.h"
 #include "../h/protosw.h"
 #include "../h/socket.h"
 #include "../h/buf.h"
 #include "../h/protosw.h"
 #include "../h/socket.h"

-#include "../h/ubareg.h"
-#include "../h/ubavar.h"
-#include "../h/enreg.h"
-#include "../h/cpu.h"
-#include "../h/mtpr.h"

 #include "../h/vmmac.h"
 #include "../h/vmmac.h"

-#include "../net/in.h"
-#include "../net/in_systm.h"
+#include <errno.h>
+

 #include "../net/if.h"
 #include "../net/if.h"

-#include "../net/if_en.h"
-#include "../net/if_uba.h"
-#include "../net/ip.h"
-#include "../net/ip_var.h"
+#include "../net/netisr.h"
+#include "../net/route.h"
+#include "../netinet/in.h"
+#include "../netinet/in_systm.h"
+#include "../netinet/ip.h"
+#include "../netinet/ip_var.h"
+#include "../netpup/pup.h"
+
+#include "../vax/cpu.h"
+#include "../vax/mtpr.h"
+#include "../vaxif/if_en.h"
+#include "../vaxif/if_enreg.h"
+#include "../vaxif/if_uba.h"
+#include "../vaxuba/ubareg.h"
+#include "../vaxuba/ubavar.h"

 
 #define        ENMTU   (1024+512)
 
 #define        ENMTU   (1024+512)

+#define        ENMRU   (1024+512+16)           /* 16 is enough to receive trailer */

 
 int    enprobe(), enattach(), enrint(), enxint(), encollide();
 struct uba_device *eninfo[NEN];
 
 int    enprobe(), enattach(), enrint(), enxint(), encollide();
 struct uba_device *eninfo[NEN];


@@ -55,7 +62,7 @@ struct        en_softc {
        struct  ifuba es_ifuba;         /* UNIBUS resources */
        short   es_delay;               /* current output delay */
        short   es_mask;                /* mask for current output delay */
        struct  ifuba es_ifuba;         /* UNIBUS resources */
        short   es_delay;               /* current output delay */
        short   es_mask;                /* mask for current output delay */

-       u_char  es_lastx;               /* host last transmitted to */
+       short   es_lastx;               /* host last transmitted to */

        short   es_oactive;             /* is output active? */
        short   es_olen;                /* length of last output */
 } en_softc[NEN];
        short   es_oactive;             /* is output active? */
        short   es_olen;                /* length of last output */
 } en_softc[NEN];


@@ -70,7 +77,6 @@ enprobe(reg)
        register int br, cvec;          /* r11, r10 value-result */
        register struct endevice *addr = (struct endevice *)reg;
 
        register int br, cvec;          /* r11, r10 value-result */
        register struct endevice *addr = (struct endevice *)reg;
 

-COUNT(ENPROBE);

 #ifdef lint
        br = 0; cvec = br; br = cvec;
        enrint(0); enxint(0); encollide(0);
 #ifdef lint
        br = 0; cvec = br; br = cvec;
        enrint(0); enxint(0); encollide(0);


@@ -81,6 +87,9 @@ COUNT(ENPROBE);
        addr->en_ostat = EN_IEN|EN_GO;
        DELAY(100000);
        addr->en_ostat = 0;
        addr->en_ostat = EN_IEN|EN_GO;
        DELAY(100000);
        addr->en_ostat = 0;

+#ifdef ECHACK
+       br = 0x16;
+#endif

        return (1);
 }
 
        return (1);
 }
 


@@ -93,26 +102,25 @@ enattach(ui)
        struct uba_device *ui;
 {
        register struct en_softc *es = &en_softc[ui->ui_unit];
        struct uba_device *ui;
 {
        register struct en_softc *es = &en_softc[ui->ui_unit];

-COUNT(ENATTACH);
+       register struct sockaddr_in *sin;

 
        es->es_if.if_unit = ui->ui_unit;
        es->es_if.if_name = "en";
        es->es_if.if_mtu = ENMTU;
        es->es_if.if_net = ui->ui_flags;
        es->es_if.if_host[0] =
 
        es->es_if.if_unit = ui->ui_unit;
        es->es_if.if_name = "en";
        es->es_if.if_mtu = ENMTU;
        es->es_if.if_net = ui->ui_flags;
        es->es_if.if_host[0] =

-           (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff;
-#ifdef ENKLUDGE
-       if (es->es_if.if_net == 10) {
-               es->es_if.if_host[0] <<= 16;
-               es->es_if.if_host[0] |= 0x4e;
-       }
-#endif
-       es->es_if.if_addr =
-           if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]);
+        (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff;
+       sin = (struct sockaddr_in *)&es->es_if.if_addr;
+       sin->sin_family = AF_INET;
+       sin->sin_addr = if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]);
+       sin = (struct sockaddr_in *)&es->es_if.if_broadaddr;
+       sin->sin_family = AF_INET;
+       sin->sin_addr = if_makeaddr(es->es_if.if_net, 0);
+       es->es_if.if_flags = IFF_BROADCAST;

        es->es_if.if_init = eninit;
        es->es_if.if_output = enoutput;
        es->es_if.if_ubareset = enreset;
        es->es_if.if_init = eninit;
        es->es_if.if_output = enoutput;
        es->es_if.if_ubareset = enreset;

-       es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16;
+       es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT;

        if_attach(&es->es_if);
 }
 
        if_attach(&es->es_if);
 }
 


@@ -124,7 +132,6 @@ enreset(unit, uban)
        int unit, uban;
 {
        register struct uba_device *ui;
        int unit, uban;
 {
        register struct uba_device *ui;

-COUNT(ENRESET);

 
        if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
            ui->ui_ubanum != uban)
 
        if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 ||
            ui->ui_ubanum != uban)


@@ -146,8 +153,9 @@ eninit(unit)
        int s;
 
        if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,
        int s;
 
        if (if_ubainit(&es->es_ifuba, ui->ui_ubanum,

-           sizeof (struct en_header), (int)btop(ENMTU)) == 0) { 
+           sizeof (struct en_header), (int)btoc(ENMRU)) == 0) { 

                printf("en%d: can't initialize\n", unit);
                printf("en%d: can't initialize\n", unit);

+               es->es_if.if_flags &= ~IFF_UP;

                return;
        }
        addr = (struct endevice *)ui->ui_addr;
                return;
        }
        addr = (struct endevice *)ui->ui_addr;


@@ -159,14 +167,18 @@ eninit(unit)
         */
        s = splimp();
        addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
         */
        s = splimp();
        addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;

-       addr->en_iwc = -(sizeof (struct en_header) + ENMTU) >> 1;
+       addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;

        addr->en_istat = EN_IEN|EN_GO;
        es->es_oactive = 1;
        addr->en_istat = EN_IEN|EN_GO;
        es->es_oactive = 1;

+       es->es_if.if_flags |= IFF_UP;

        enxint(unit);
        splx(s);
        enxint(unit);
        splx(s);

+       if_rtinit(&es->es_if, RTF_UP);

 }
 
 }
 

-int    enlastdel = 25;
+int    enalldelay = 0;
+int    enlastdel = 50;
+int    enlastmask = (~0) << 5;

 
 /*
  * Start or restart output on interface.
 
 /*
  * Start or restart output on interface.


@@ -185,7 +197,6 @@ enstart(dev)
        register struct endevice *addr;
        struct mbuf *m;
        int dest;
        register struct endevice *addr;
        struct mbuf *m;
        int dest;

-COUNT(ENSTART);

 
        if (es->es_oactive)
                goto restart;
 
        if (es->es_oactive)
                goto restart;


@@ -205,21 +216,25 @@ COUNT(ENSTART);
 
        /*
         * Ethernet cannot take back-to-back packets (no
 
        /*
         * Ethernet cannot take back-to-back packets (no

-        * buffering in interface.  To avoid overrunning
-        * receiver, enforce a small delay (about 1ms) in interface
-        * on successive packets sent to same host.
+        * buffering in interface.  To help avoid overrunning
+        * receivers, enforce a small delay (about 1ms) in interface:
+        *      * between all packets when enalldelay
+        *      * whenever last packet was broadcast
+        *      * whenever this packet is to same host as last packet

         */
         */

-       if (es->es_lastx && es->es_lastx == dest)
+       if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) {

                es->es_delay = enlastdel;
                es->es_delay = enlastdel;

-       else
-               es->es_lastx = dest;
+               es->es_mask = enlastmask;
+       }
+       es->es_lastx = dest;

 
 restart:
        /*
         * Have request mapped to UNIBUS for transmission.
         * Purge any stale data from this BDP, and start the otput.
         */
 
 restart:
        /*
         * Have request mapped to UNIBUS for transmission.
         * Purge any stale data from this BDP, and start the otput.
         */

-       UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);
+       if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
+               UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp);

        addr = (struct endevice *)ui->ui_addr;
        addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
        addr->en_odelay = es->es_delay;
        addr = (struct endevice *)ui->ui_addr;
        addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info;
        addr->en_odelay = es->es_delay;


@@ -237,26 +252,25 @@ enxint(unit)
 {
        register struct uba_device *ui = eninfo[unit];
        register struct en_softc *es = &en_softc[unit];
 {
        register struct uba_device *ui = eninfo[unit];
        register struct en_softc *es = &en_softc[unit];

-       register struct endevice *addr;
-COUNT(ENXINT);
+       register struct endevice *addr = (struct endevice *)ui->ui_addr;

 
        if (es->es_oactive == 0)
                return;
 
        if (es->es_oactive == 0)
                return;

-       addr = (struct endevice *)ui->ui_addr;
+       if (es->es_mask && (addr->en_ostat&EN_OERROR)) {
+               es->es_if.if_oerrors++;
+               endocoll(unit);
+               return;
+       }

        es->es_if.if_opackets++;
        es->es_oactive = 0;
        es->es_delay = 0;
        es->es_mask = ~0;
        es->es_if.if_opackets++;
        es->es_oactive = 0;
        es->es_delay = 0;
        es->es_mask = ~0;

-       if (addr->en_ostat&EN_OERROR) {
-               es->es_if.if_oerrors++;
-               printf("en%d: output error\n", unit);
-       }

        if (es->es_ifuba.ifu_xtofree) {
                m_freem(es->es_ifuba.ifu_xtofree);
                es->es_ifuba.ifu_xtofree = 0;
        }
        if (es->es_if.if_snd.ifq_head == 0) {
        if (es->es_ifuba.ifu_xtofree) {
                m_freem(es->es_ifuba.ifu_xtofree);
                es->es_ifuba.ifu_xtofree = 0;
        }
        if (es->es_if.if_snd.ifq_head == 0) {

-               es->es_lastx = 0;
+               es->es_lastx = 256;             /* putatively illegal */

                return;
        }
        enstart(unit);
                return;
        }
        enstart(unit);


@@ -265,17 +279,24 @@ COUNT(ENXINT);
 /*
  * Collision on ethernet interface.  Do exponential
  * backoff, and retransmit.  If have backed off all
 /*
  * Collision on ethernet interface.  Do exponential
  * backoff, and retransmit.  If have backed off all

- * the way printing warning diagnostic, and drop packet.
+ * the way print warning diagnostic, and drop packet.

  */
 encollide(unit)
        int unit;
 {
  */
 encollide(unit)
        int unit;
 {

-       register struct en_softc *es = &en_softc[unit];
-COUNT(ENCOLLIDE);
+       struct en_softc *es = &en_softc[unit];

 
        es->es_if.if_collisions++;
        if (es->es_oactive == 0)
                return;
 
        es->es_if.if_collisions++;
        if (es->es_oactive == 0)
                return;

+       endocoll(unit);
+}
+
+endocoll(unit)
+       int unit;
+{
+       register struct en_softc *es = &en_softc[unit];
+

        /*
         * Es_mask is a 16 bit number with n low zero bits, with
         * n the number of backoffs.  When es_mask is 0 we have
        /*
         * Es_mask is a 16 bit number with n low zero bits, with
         * n the number of backoffs.  When es_mask is 0 we have


@@ -295,7 +316,9 @@ COUNT(ENCOLLIDE);
        enstart(unit);
 }
 
        enstart(unit);
 }
 

-int    enprintierrors;
+struct sockaddr_pup pupsrc = { AF_PUP };
+struct sockaddr_pup pupdst = { AF_PUP };
+struct sockproto pupproto = { PF_PUP };

 /*
  * Ethernet interface receiver interrupt.
  * If input error just drop packet.
 /*
  * Ethernet interface receiver interrupt.
  * If input error just drop packet.


@@ -312,85 +335,102 @@ enrint(unit)
        struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
        register struct en_header *en;
        struct mbuf *m;
        struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr;
        register struct en_header *en;
        struct mbuf *m;

-       int len;
+       int len; short resid;

        register struct ifqueue *inq;
        int off;
        register struct ifqueue *inq;
        int off;

-COUNT(ENRINT);

 
        es->es_if.if_ipackets++;
 
        /*
         * Purge BDP; drop if input error indicated.
         */
 
        es->es_if.if_ipackets++;
 
        /*
         * Purge BDP; drop if input error indicated.
         */

-       UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);
+       if (es->es_ifuba.ifu_flags & UBA_NEEDBDP)
+               UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp);

        if (addr->en_istat&EN_IERROR) {
                es->es_if.if_ierrors++;
        if (addr->en_istat&EN_IERROR) {
                es->es_if.if_ierrors++;

-               if (enprintierrors)
-               printf("en%d: input error\n", unit);

                goto setup;
        }
 
        /*
                goto setup;
        }
 
        /*

+        * Calculate input data length.

         * Get pointer to ethernet header (in input buffer).
         * Deal with trailer protocol: if type is PUP trailer
         * get true type from first 16-bit word past data.
         * Remember that type was trailer by setting off.
         */
         * Get pointer to ethernet header (in input buffer).
         * Deal with trailer protocol: if type is PUP trailer
         * get true type from first 16-bit word past data.
         * Remember that type was trailer by setting off.
         */

+       resid = addr->en_iwc;
+       if (resid)
+               resid |= 0176000;
+       len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1;
+       len -= sizeof (struct en_header);
+       if (len > ENMRU)
+               goto setup;                     /* sanity */

        en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
 #define        endataaddr(en, off, type)       ((type)(((caddr_t)((en)+1)+(off))))
        if (en->en_type >= ENPUP_TRAIL &&
            en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) {
                off = (en->en_type - ENPUP_TRAIL) * 512;
        en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr);
 #define        endataaddr(en, off, type)       ((type)(((caddr_t)((en)+1)+(off))))
        if (en->en_type >= ENPUP_TRAIL &&
            en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) {
                off = (en->en_type - ENPUP_TRAIL) * 512;

-               if (off >= ENMTU)
+               if (off > ENMTU)

                        goto setup;             /* sanity */
                en->en_type = *endataaddr(en, off, u_short *);
                        goto setup;             /* sanity */
                en->en_type = *endataaddr(en, off, u_short *);

+               resid = *(endataaddr(en, off+2, u_short *));
+               if (off + resid > len)
+                       goto setup;             /* sanity */
+               len = off + resid;

        } else
                off = 0;
        } else
                off = 0;

-
+       if (len == 0)
+               goto setup;

        /*
        /*

-        * Attempt to infer packet length from type;
-        * can't deal with packet if can't infer length.
+        * Pull packet off interface.  Off is nonzero if packet
+        * has trailing header; if_rubaget will then force this header
+        * information to be at the front, but we still have to drop
+        * the type and length which are at the front of any trailer data.

         */
         */

+       m = if_rubaget(&es->es_ifuba, len, off);
+       if (m == 0)
+               goto setup;
+       if (off) {
+               m->m_off += 2 * sizeof (u_short);
+               m->m_len -= 2 * sizeof (u_short);
+       }

        switch (en->en_type) {
 
 #ifdef INET
        case ENPUP_IPTYPE:
        switch (en->en_type) {
 
 #ifdef INET
        case ENPUP_IPTYPE:

-               len = htons((u_short)endataaddr(en, off ? off+2 : 0, struct ip *)->ip_len);
-               if (off)
-                       len += 2;
-               setipintr();
+               schednetisr(NETISR_IP);

                inq = &ipintrq;
                break;
 #endif
                inq = &ipintrq;
                break;
 #endif

-
-       default:
-               printf("en%d: unknow pkt type 0x%x\n", en->en_type);
+#ifdef PUP
+       case ENPUP_PUPTYPE: {
+               struct pup_header *pup = mtod(m, struct pup_header *);
+
+               pupproto.sp_protocol = pup->pup_type;
+               pupdst.spup_addr = pup->pup_dport;
+               pupsrc.spup_addr = pup->pup_sport;
+               raw_input(m, &pupproto, (struct sockaddr *)&pupsrc,
+                 (struct sockaddr *)&pupdst);

                goto setup;
        }
                goto setup;
        }

-       if (len == 0)
-               goto setup;
-
-       /*
-        * Pull packet off interface.  Off is nonzero if packet
-        * has trailing header; if_rubaget will then force this header
-        * information to be at the front, but we still have to drop
-        * the two-byte type which is at the front of any trailer data.
-        */
-       m = if_rubaget(&es->es_ifuba, len, off);
-       if (m == 0)
+#endif
+       default:
+               m_freem(m);

                goto setup;
                goto setup;

-       if (off) {
-               m->m_off += 2;
-               m->m_len -= 2;

        }
        }

-       IF_ENQUEUE(inq, m);
+
+       if (IF_QFULL(inq)) {
+               IF_DROP(inq);
+               m_freem(m);
+       } else
+               IF_ENQUEUE(inq, m);

 
 setup:
        /*
         * Reset for next packet.
         */
        addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;
 
 setup:
        /*
         * Reset for next packet.
         */
        addr->en_iba = es->es_ifuba.ifu_r.ifrw_info;

-       addr->en_iwc = -(sizeof (struct en_header) + ENMTU) >> 1;
+       addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1;

        addr->en_istat = EN_IEN|EN_GO;
 }
 
        addr->en_istat = EN_IEN|EN_GO;
 }
 


@@ -400,48 +440,53 @@ setup:
  * Use trailer local net encapsulation if enough data in first
  * packet leaves a multiple of 512 bytes of data in remainder.
  */
  * Use trailer local net encapsulation if enough data in first
  * packet leaves a multiple of 512 bytes of data in remainder.
  */

-enoutput(ifp, m0, pf)
+enoutput(ifp, m0, dst)

        struct ifnet *ifp;
        struct mbuf *m0;
        struct ifnet *ifp;
        struct mbuf *m0;

-       int pf;
+       struct sockaddr *dst;

 {
 {

-       int type, dest;
+       int type, dest, s, error;

        register struct mbuf *m = m0;
        register struct en_header *en;
        register struct mbuf *m = m0;
        register struct en_header *en;

-       int s;
+       register int off;

 
 

-       switch (pf) {
+       switch (dst->sa_family) {

 
 #ifdef INET
 
 #ifdef INET

-       case PF_INET: {
-               register struct ip *ip = mtod(m0, struct ip *);
-               int off;
-
-#ifndef ENKLUDGE
-               dest = ip->ip_dst.s_addr >> 24;
-#else
-               dest = (ip->ip_dst.s_addr >> 8) & 0xff;
-#endif
-               off = ntohs((u_short)ip->ip_len) - m->m_len;
-#ifndef ENKLUDGE
-               if (off > 0 && (off & 0x1ff) == 0 && m->m_off >= MMINOFF + 2) {
+       case AF_INET:
+               dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr;
+               if (dest & 0x00ffff00) {
+                       error = EPERM;          /* ??? */
+                       goto bad;
+               }
+               dest = (dest >> 24) & 0xff;
+               off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
+               if (off > 0 && (off & 0x1ff) == 0 &&
+                   m->m_off >= MMINOFF + 2 * sizeof (u_short)) {

                        type = ENPUP_TRAIL + (off>>9);
                        type = ENPUP_TRAIL + (off>>9);

-                       m->m_off -= 2;
-                       m->m_len += 2;
+                       m->m_off -= 2 * sizeof (u_short);
+                       m->m_len += 2 * sizeof (u_short);

                        *mtod(m, u_short *) = ENPUP_IPTYPE;
                        *mtod(m, u_short *) = ENPUP_IPTYPE;

+                       *(mtod(m, u_short *) + 1) = m->m_len;

                        goto gottrailertype;
                }
                        goto gottrailertype;
                }

-#endif

                type = ENPUP_IPTYPE;
                off = 0;
                goto gottype;
                type = ENPUP_IPTYPE;
                off = 0;
                goto gottype;

-               }
+#endif
+#ifdef PUP
+       case AF_PUP:
+               dest = ((struct sockaddr_pup *)dst)->spup_addr.pp_host;
+               type = ENPUP_PUPTYPE;
+               off = 0;
+               goto gottype;

 #endif
 
        default:
 #endif
 
        default:

-               printf("en%d: can't encapsulate pf%d\n", ifp->if_unit, pf);
-               m_freem(m0);
-               return (0);
+               printf("en%d: can't handle af%d\n", ifp->if_unit,
+                       dst->sa_family);
+               error = EAFNOSUPPORT;
+               goto bad;

        }
 
 gottrailertype:
        }
 
 gottrailertype:


@@ -465,8 +510,8 @@ gottype:
            MMINOFF + sizeof (struct en_header) > m->m_off) {
                m = m_get(M_DONTWAIT);
                if (m == 0) {
            MMINOFF + sizeof (struct en_header) > m->m_off) {
                m = m_get(M_DONTWAIT);
                if (m == 0) {

-                       m_freem(m0);
-                       return (0);
+                       error = ENOBUFS;
+                       goto bad;

                }
                m->m_next = m0;
                m->m_off = MMINOFF;
                }
                m->m_next = m0;
                m->m_off = MMINOFF;


@@ -485,9 +530,20 @@ gottype:
         * not yet active.
         */
        s = splimp();
         * not yet active.
         */
        s = splimp();

+       if (IF_QFULL(&ifp->if_snd)) {
+               IF_DROP(&ifp->if_snd);
+               error = ENOBUFS;
+               goto qfull;
+       }

        IF_ENQUEUE(&ifp->if_snd, m);
        if (en_softc[ifp->if_unit].es_oactive == 0)
                enstart(ifp->if_unit);
        splx(s);
        IF_ENQUEUE(&ifp->if_snd, m);
        if (en_softc[ifp->if_unit].es_oactive == 0)
                enstart(ifp->if_unit);
        splx(s);

-       return (1);
+       return (0);
+qfull:
+       m0 = m;
+       splx(s);
+bad:
+       m_freem(m0);
+       return (error);

 }
 }