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[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [libnetworking/] [kern/] [uipc_mbuf.c] - Blame information for rev 173

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/*
 * Copyright (c) 1982, 1986, 1988, 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94
 * $Id: uipc_mbuf.c,v 1.2 2001-09-27 12:01:51 chris Exp $
 */
 
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#define MBTYPES
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/domain.h>
#include <sys/protosw.h>
 
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_extern.h>
 
static void mbinit __P((void *))  __attribute__ ((unused));
SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbinit, NULL)
 
struct mbuf *mbutl;
char    *mclrefcnt;
struct mbstat mbstat;
struct mbuf *mmbfree;
union mcluster *mclfree;
int     max_linkhdr;
int     max_protohdr;
int     max_hdr;
int     max_datalen;
 
/* "number of clusters of pages" */
#define NCL_INIT        1
 
#define NMB_INIT        16
 
/*
 * When MGET failes, ask protocols to free space when short of memory,
 * then re-attempt to allocate an mbuf.
 */
struct mbuf *
m_retry(i, t)
        int i, t;
{
        register struct mbuf *m;
 
        m_reclaim();
#define m_retry(i, t)   (struct mbuf *)0
        MGET(m, i, t);
#undef m_retry
        if (m != NULL)
                mbstat.m_wait++;
        else
                mbstat.m_drops++;
        return (m);
}
 
/*
 * As above; retry an MGETHDR.
 */
struct mbuf *
m_retryhdr(i, t)
        int i, t;
{
        register struct mbuf *m;
 
        m_reclaim();
#define m_retryhdr(i, t) (struct mbuf *)0
        MGETHDR(m, i, t);
#undef m_retryhdr
        if (m != NULL)
                mbstat.m_wait++;
        else
                mbstat.m_drops++;
        return (m);
}
 
void
m_reclaim(void)
{
        register struct domain *dp;
        register struct protosw *pr;
        int s = splimp();
 
        for (dp = domains; dp; dp = dp->dom_next)
                for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
                        if (pr->pr_drain)
                                (*pr->pr_drain)();
        splx(s);
        mbstat.m_drain++;
}
 
/*
 * Space allocation routines.
 * These are also available as macros
 * for critical paths.
 */
struct mbuf *
m_get(nowait, type)
        int nowait, type;
{
        register struct mbuf *m;
 
        MGET(m, nowait, type);
        return (m);
}
 
struct mbuf *
m_gethdr(nowait, type)
        int nowait, type;
{
        register struct mbuf *m;
 
        MGETHDR(m, nowait, type);
        return (m);
}
 
struct mbuf *
m_getclr(nowait, type)
        int nowait, type;
{
        register struct mbuf *m;
 
        MGET(m, nowait, type);
        if (m == 0)
                return (0);
        bzero(mtod(m, caddr_t), MLEN);
        return (m);
}
 
struct mbuf *
m_free(m)
        struct mbuf *m;
{
        register struct mbuf *n;
 
        MFREE(m, n);
        return (n);
}
 
void
m_freem(m)
        register struct mbuf *m;
{
        register struct mbuf *n;
 
        if (m == NULL)
                return;
        do {
                MFREE(m, n);
                m = n;
        } while (m);
}
 
/*
 * Mbuffer utility routines.
 */
 
/*
 * Lesser-used path for M_PREPEND:
 * allocate new mbuf to prepend to chain,
 * copy junk along.
 */
struct mbuf *
m_prepend(m, len, how)
        register struct mbuf *m;
        int len, how;
{
        struct mbuf *mn;
 
        MGET(mn, how, m->m_type);
        if (mn == (struct mbuf *)NULL) {
                m_freem(m);
                return ((struct mbuf *)NULL);
        }
        if (m->m_flags & M_PKTHDR) {
                M_COPY_PKTHDR(mn, m);
                m->m_flags &= ~M_PKTHDR;
        }
        mn->m_next = m;
        m = mn;
        if (len < MHLEN)
                MH_ALIGN(m, len);
        m->m_len = len;
        return (m);
}
 
/*
 * Make a copy of an mbuf chain starting "off0" bytes from the beginning,
 * continuing for "len" bytes.  If len is M_COPYALL, copy to end of mbuf.
 * The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller.
 */
static int MCFail;
 
struct mbuf *
m_copym(m, off0, len, wait)
        register struct mbuf *m;
        int off0, wait;
        register int len;
{
        register struct mbuf *n, **np;
        register int off = off0;
        struct mbuf *top;
        int copyhdr = 0;
 
        if (off < 0 || len < 0)
                panic("m_copym");
        if (off == 0 && m->m_flags & M_PKTHDR)
                copyhdr = 1;
        while (off > 0) {
                if (m == 0)
                        panic("m_copym");
                if (off < m->m_len)
                        break;
                off -= m->m_len;
                m = m->m_next;
        }
        np = &top;
        top = 0;
        while (len > 0) {
                if (m == 0) {
                        if (len != M_COPYALL)
                                panic("m_copym");
                        break;
                }
                MGET(n, wait, m->m_type);
                *np = n;
                if (n == 0)
                        goto nospace;
                if (copyhdr) {
                        M_COPY_PKTHDR(n, m);
                        if (len == M_COPYALL)
                                n->m_pkthdr.len -= off0;
                        else
                                n->m_pkthdr.len = len;
                        copyhdr = 0;
                }
                n->m_len = min(len, m->m_len - off);
                if (m->m_flags & M_EXT) {
                        n->m_data = m->m_data + off;
                        if(!m->m_ext.ext_ref)
                                mclrefcnt[mtocl(m->m_ext.ext_buf)]++;
                        else
                                (*(m->m_ext.ext_ref))(m->m_ext.ext_buf,
                                                        m->m_ext.ext_size);
                        n->m_ext = m->m_ext;
                        n->m_flags |= M_EXT;
                } else
                        bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t),
                            (unsigned)n->m_len);
                if (len != M_COPYALL)
                        len -= n->m_len;
                off = 0;
                m = m->m_next;
                np = &n->m_next;
        }
        if (top == 0)
                MCFail++;
        return (top);
nospace:
        m_freem(top);
        MCFail++;
        return (0);
}
 
/*
 * Copy an entire packet, including header (which must be present).
 * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'.
 */
struct mbuf *
m_copypacket(m, how)
        struct mbuf *m;
        int how;
{
        struct mbuf *top, *n, *o;
 
        MGET(n, how, m->m_type);
        top = n;
        if (!n)
                goto nospace;
 
        M_COPY_PKTHDR(n, m);
        n->m_len = m->m_len;
        if (m->m_flags & M_EXT) {
                n->m_data = m->m_data;
                mclrefcnt[mtocl(m->m_ext.ext_buf)]++;
                n->m_ext = m->m_ext;
                n->m_flags |= M_EXT;
        } else {
                bcopy(mtod(m, char *), mtod(n, char *), n->m_len);
        }
 
        m = m->m_next;
        while (m) {
                MGET(o, how, m->m_type);
                if (!o)
                        goto nospace;
 
                n->m_next = o;
                n = n->m_next;
 
                n->m_len = m->m_len;
                if (m->m_flags & M_EXT) {
                        n->m_data = m->m_data;
                        mclrefcnt[mtocl(m->m_ext.ext_buf)]++;
                        n->m_ext = m->m_ext;
                        n->m_flags |= M_EXT;
                } else {
                        bcopy(mtod(m, char *), mtod(n, char *), n->m_len);
                }
 
                m = m->m_next;
        }
        return top;
nospace:
        m_freem(top);
        MCFail++;
        return 0;
}
 
/*
 * Copy data from an mbuf chain starting "off" bytes from the beginning,
 * continuing for "len" bytes, into the indicated buffer.
 */
void
m_copydata(m, off, len, cp)
        register struct mbuf *m;
        register int off;
        register int len;
        caddr_t cp;
{
        register unsigned count;
 
        if (off < 0 || len < 0)
                panic("m_copydata");
        while (off > 0) {
                if (m == 0)
                        panic("m_copydata");
                if (off < m->m_len)
                        break;
                off -= m->m_len;
                m = m->m_next;
        }
        while (len > 0) {
                if (m == 0)
                        panic("m_copydata");
                count = min(m->m_len - off, len);
                bcopy(mtod(m, caddr_t) + off, cp, count);
                len -= count;
                cp += count;
                off = 0;
                m = m->m_next;
        }
}
 
/*
 * Concatenate mbuf chain n to m.
 * Both chains must be of the same type (e.g. MT_DATA).
 * Any m_pkthdr is not updated.
 */
void
m_cat(m, n)
        register struct mbuf *m, *n;
{
        while (m->m_next)
                m = m->m_next;
        while (n) {
                if (m->m_flags & M_EXT ||
                    m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) {
                        /* just join the two chains */
                        m->m_next = n;
                        return;
                }
                /* splat the data from one into the other */
                bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len,
                    (u_int)n->m_len);
                m->m_len += n->m_len;
                n = m_free(n);
        }
}
 
void
m_adj(mp, req_len)
        struct mbuf *mp;
        int req_len;
{
        register int len = req_len;
        register struct mbuf *m;
        register int count;
 
        if ((m = mp) == NULL)
                return;
        if (len >= 0) {
                /*
                 * Trim from head.
                 */
                while (m != NULL && len > 0) {
                        if (m->m_len <= len) {
                                len -= m->m_len;
                                m->m_len = 0;
                                m = m->m_next;
                        } else {
                                m->m_len -= len;
                                m->m_data += len;
                                len = 0;
                        }
                }
                m = mp;
                if (mp->m_flags & M_PKTHDR)
                        m->m_pkthdr.len -= (req_len - len);
        } else {
                /*
                 * Trim from tail.  Scan the mbuf chain,
                 * calculating its length and finding the last mbuf.
                 * If the adjustment only affects this mbuf, then just
                 * adjust and return.  Otherwise, rescan and truncate
                 * after the remaining size.
                 */
                len = -len;
                count = 0;
                for (;;) {
                        count += m->m_len;
                        if (m->m_next == (struct mbuf *)0)
                                break;
                        m = m->m_next;
                }
                if (m->m_len >= len) {
                        m->m_len -= len;
                        if (mp->m_flags & M_PKTHDR)
                                mp->m_pkthdr.len -= len;
                        return;
                }
                count -= len;
                if (count < 0)
                        count = 0;
                /*
                 * Correct length for chain is "count".
                 * Find the mbuf with last data, adjust its length,
                 * and toss data from remaining mbufs on chain.
                 */
                m = mp;
                if (m->m_flags & M_PKTHDR)
                        m->m_pkthdr.len = count;
                for (; m; m = m->m_next) {
                        if (m->m_len >= count) {
                                m->m_len = count;
                                break;
                        }
                        count -= m->m_len;
                }
                while (m->m_next)
                        (m = m->m_next) ->m_len = 0;
        }
}
 
/*
 * Rearange an mbuf chain so that len bytes are contiguous
 * and in the data area of an mbuf (so that mtod and dtom
 * will work for a structure of size len).  Returns the resulting
 * mbuf chain on success, frees it and returns null on failure.
 * If there is room, it will add up to max_protohdr-len extra bytes to the
 * contiguous region in an attempt to avoid being called next time.
 */
static int MPFail;
 
struct mbuf *
m_pullup(n, len)
        register struct mbuf *n;
        int len;
{
        register struct mbuf *m;
        register int count;
        int space;
 
        /*
         * If first mbuf has no cluster, and has room for len bytes
         * without shifting current data, pullup into it,
         * otherwise allocate a new mbuf to prepend to the chain.
         */
        if ((n->m_flags & M_EXT) == 0 &&
            n->m_data + len < &n->m_dat[MLEN] && n->m_next) {
                if (n->m_len >= len)
                        return (n);
                m = n;
                n = n->m_next;
                len -= m->m_len;
        } else {
                if (len > MHLEN)
                        goto bad;
                MGET(m, M_DONTWAIT, n->m_type);
                if (m == 0)
                        goto bad;
                m->m_len = 0;
                if (n->m_flags & M_PKTHDR) {
                        M_COPY_PKTHDR(m, n);
                        n->m_flags &= ~M_PKTHDR;
                }
        }
        space = &m->m_dat[MLEN] - (m->m_data + m->m_len);
        do {
                count = min(min(max(len, max_protohdr), space), n->m_len);
                bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len,
                  (unsigned)count);
                len -= count;
                m->m_len += count;
                n->m_len -= count;
                space -= count;
                if (n->m_len)
                        n->m_data += count;
                else
                        n = m_free(n);
        } while (len > 0 && n);
        if (len > 0) {
                (void) m_free(m);
                goto bad;
        }
        m->m_next = n;
        return (m);
bad:
        m_freem(n);
        MPFail++;
        return (0);
}
 
/*
 * Partition an mbuf chain in two pieces, returning the tail --
 * all but the first len0 bytes.  In case of failure, it returns NULL and
 * attempts to restore the chain to its original state.
 */
struct mbuf *
m_split(m0, len0, wait)
        register struct mbuf *m0;
        int len0, wait;
{
        register struct mbuf *m, *n;
        unsigned len = len0, remain;
 
        for (m = m0; m && len > m->m_len; m = m->m_next)
                len -= m->m_len;
        if (m == 0)
                return (0);
        remain = m->m_len - len;
        if (m0->m_flags & M_PKTHDR) {
                MGETHDR(n, wait, m0->m_type);
                if (n == 0)
                        return (0);
                n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif;
                n->m_pkthdr.len = m0->m_pkthdr.len - len0;
                m0->m_pkthdr.len = len0;
                if (m->m_flags & M_EXT)
                        goto extpacket;
                if (remain > MHLEN) {
                        /* m can't be the lead packet */
                        MH_ALIGN(n, 0);
                        n->m_next = m_split(m, len, wait);
                        if (n->m_next == 0) {
                                (void) m_free(n);
                                return (0);
                        } else
                                return (n);
                } else
                        MH_ALIGN(n, remain);
        } else if (remain == 0) {
                n = m->m_next;
                m->m_next = 0;
                return (n);
        } else {
                MGET(n, wait, m->m_type);
                if (n == 0)
                        return (0);
                M_ALIGN(n, remain);
        }
extpacket:
        if (m->m_flags & M_EXT) {
                n->m_flags |= M_EXT;
                n->m_ext = m->m_ext;
                if(!m->m_ext.ext_ref)
                        mclrefcnt[mtocl(m->m_ext.ext_buf)]++;
                else
                        (*(m->m_ext.ext_ref))(m->m_ext.ext_buf,
                                                m->m_ext.ext_size);
                m->m_ext.ext_size = 0; /* For Accounting XXXXXX danger */
                n->m_data = m->m_data + len;
        } else {
                bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain);
        }
        n->m_len = remain;
        m->m_len = len;
        n->m_next = m->m_next;
        m->m_next = 0;
        return (n);
}
/*
 * Routine to copy from device local memory into mbufs.
 */
struct mbuf *
m_devget(buf, totlen, off0, ifp, copy)
        char *buf;
        int totlen, off0;
        struct ifnet *ifp;
        void (*copy) __P((char *from, caddr_t to, u_int len));
{
        register struct mbuf *m;
        struct mbuf *top = 0, **mp = &top;
        register int off = off0, len;
        register char *cp;
        char *epkt;
 
        cp = buf;
        epkt = cp + totlen;
        if (off) {
                cp += off + 2 * sizeof(u_short);
                totlen -= 2 * sizeof(u_short);
        }
        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (m == 0)
                return (0);
        m->m_pkthdr.rcvif = ifp;
        m->m_pkthdr.len = totlen;
        m->m_len = MHLEN;
 
        while (totlen > 0) {
                if (top) {
                        MGET(m, M_DONTWAIT, MT_DATA);
                        if (m == 0) {
                                m_freem(top);
                                return (0);
                        }
                        m->m_len = MLEN;
                }
                len = min(totlen, epkt - cp);
                if (len >= MINCLSIZE) {
                        MCLGET(m, M_DONTWAIT);
                        if (m->m_flags & M_EXT)
                                m->m_len = len = min(len, MCLBYTES);
                        else
                                len = m->m_len;
                } else {
                        /*
                         * Place initial small packet/header at end of mbuf.
                         */
                        if (len < m->m_len) {
                                if (top == 0 && len + max_linkhdr <= m->m_len)
                                        m->m_data += max_linkhdr;
                                m->m_len = len;
                        } else
                                len = m->m_len;
                }
                if (copy)
                        copy(cp, mtod(m, caddr_t), (unsigned)len);
                else
                        bcopy(cp, mtod(m, caddr_t), (unsigned)len);
                cp += len;
                *mp = m;
                mp = &m->m_next;
                totlen -= len;
                if (cp == epkt)
                        cp = buf;
        }
        return (top);
}
 
/*
 * Copy data from a buffer back into the indicated mbuf chain,
 * starting "off" bytes from the beginning, extending the mbuf
 * chain if necessary.
 */
void
m_copyback(m0, off, len, cp)
        struct  mbuf *m0;
        register int off;
        register int len;
        caddr_t cp;
{
        register int mlen;
        register struct mbuf *m = m0, *n;
        int totlen = 0;
 
        if (m0 == 0)
                return;
        while (off > (mlen = m->m_len)) {
                off -= mlen;
                totlen += mlen;
                if (m->m_next == 0) {
                        n = m_getclr(M_DONTWAIT, m->m_type);
                        if (n == 0)
                                goto out;
                        n->m_len = min(MLEN, len + off);
                        m->m_next = n;
                }
                m = m->m_next;
        }
        while (len > 0) {
                mlen = min (m->m_len - off, len);
                bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen);
                cp += mlen;
                len -= mlen;
                mlen += off;
                off = 0;
                totlen += mlen;
                if (len == 0)
                        break;
                if (m->m_next == 0) {
                        n = m_get(M_DONTWAIT, m->m_type);
                        if (n == 0)
                                break;
                        n->m_len = min(MLEN, len);
                        m->m_next = n;
                }
                m = m->m_next;
        }
out:    if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen))
                m->m_pkthdr.len = totlen;
}

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[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [libnetworking/] [kern/] [uipc_mbuf.c] - Blame information for rev 173

Line No.	Rev	Author	Line
1	30	unneback	`/*`
2			`* Copyright (c) 1982, 1986, 1988, 1991, 1993`
3			`* The Regents of the University of California. All rights reserved.`
4			`*`
5			`* Redistribution and use in source and binary forms, with or without`
6			`* modification, are permitted provided that the following conditions`
7			`* are met:`
8			`* 1. Redistributions of source code must retain the above copyright`
9			`* notice, this list of conditions and the following disclaimer.`
10			`* 2. Redistributions in binary form must reproduce the above copyright`
11			`* notice, this list of conditions and the following disclaimer in the`
12			`* documentation and/or other materials provided with the distribution.`
13			`* 3. All advertising materials mentioning features or use of this software`
14			`* must display the following acknowledgement:`
15			`* This product includes software developed by the University of`
16			`* California, Berkeley and its contributors.`
17			`* 4. Neither the name of the University nor the names of its contributors`
18			`* may be used to endorse or promote products derived from this software`
19			`* without specific prior written permission.`
20			`*`
21			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22			`* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE`
23			`* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE`
24			`* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE`
25			`* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL`
26			`* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS`
27			`* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)`
28			`* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT`
29			`* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY`
30			`* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF`
31			`* SUCH DAMAGE.`
32			`*`
33			`* @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94`
34			`* $Id: uipc_mbuf.c,v 1.2 2001-09-27 12:01:51 chris Exp $`
35			`*/`
36
37			`#include <sys/param.h>`
38			`#include <sys/systm.h>`
39			`#include <sys/proc.h>`
40			`#include <sys/malloc.h>`
41			`#define MBTYPES`
42			`#include <sys/mbuf.h>`
43			`#include <sys/kernel.h>`
44			`#include <sys/syslog.h>`
45			`#include <sys/domain.h>`
46			`#include <sys/protosw.h>`
47
48			`#include <vm/vm.h>`
49			`#include <vm/vm_param.h>`
50			`#include <vm/vm_kern.h>`
51			`#include <vm/vm_extern.h>`
52
53			`static void mbinit __P((void *)) __attribute__ ((unused));`
54			`SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbinit, NULL)`
55
56			`struct mbuf *mbutl;`
57			`char *mclrefcnt;`
58			`struct mbstat mbstat;`
59			`struct mbuf *mmbfree;`
60			`union mcluster *mclfree;`
61			`int max_linkhdr;`
62			`int max_protohdr;`
63			`int max_hdr;`
64			`int max_datalen;`
65
66			`/* "number of clusters of pages" */`
67			`#define NCL_INIT 1`
68
69			`#define NMB_INIT 16`
70
71			`/*`
72			`* When MGET failes, ask protocols to free space when short of memory,`
73			`* then re-attempt to allocate an mbuf.`
74			`*/`
75			`struct mbuf *`
76			`m_retry(i, t)`
77			`int i, t;`
78			`{`
79			`register struct mbuf *m;`
80
81			`m_reclaim();`
82			`#define m_retry(i, t) (struct mbuf *)0`
83			`MGET(m, i, t);`
84			`#undef m_retry`
85			`if (m != NULL)`
86			`mbstat.m_wait++;`
87			`else`
88			`mbstat.m_drops++;`
89			`return (m);`
90			`}`
91
92			`/*`
93			`* As above; retry an MGETHDR.`
94			`*/`
95			`struct mbuf *`
96			`m_retryhdr(i, t)`
97			`int i, t;`
98			`{`
99			`register struct mbuf *m;`
100
101			`m_reclaim();`
102			`#define m_retryhdr(i, t) (struct mbuf *)0`
103			`MGETHDR(m, i, t);`
104			`#undef m_retryhdr`
105			`if (m != NULL)`
106			`mbstat.m_wait++;`
107			`else`
108			`mbstat.m_drops++;`
109			`return (m);`
110			`}`
111
112			`void`
113			`m_reclaim(void)`
114			`{`
115			`register struct domain *dp;`
116			`register struct protosw *pr;`
117			`int s = splimp();`
118
119			`for (dp = domains; dp; dp = dp->dom_next)`
120			`for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)`
121			`if (pr->pr_drain)`
122			`(*pr->pr_drain)();`
123			`splx(s);`
124			`mbstat.m_drain++;`
125			`}`
126
127			`/*`
128			`* Space allocation routines.`
129			`* These are also available as macros`
130			`* for critical paths.`
131			`*/`
132			`struct mbuf *`
133			`m_get(nowait, type)`
134			`int nowait, type;`
135			`{`
136			`register struct mbuf *m;`
137
138			`MGET(m, nowait, type);`
139			`return (m);`
140			`}`
141
142			`struct mbuf *`
143			`m_gethdr(nowait, type)`
144			`int nowait, type;`
145			`{`
146			`register struct mbuf *m;`
147
148			`MGETHDR(m, nowait, type);`
149			`return (m);`
150			`}`
151
152			`struct mbuf *`
153			`m_getclr(nowait, type)`
154			`int nowait, type;`
155			`{`
156			`register struct mbuf *m;`
157
158			`MGET(m, nowait, type);`
159			`if (m == 0)`
160			`return (0);`
161			`bzero(mtod(m, caddr_t), MLEN);`
162			`return (m);`
163			`}`
164
165			`struct mbuf *`
166			`m_free(m)`
167			`struct mbuf *m;`
168			`{`
169			`register struct mbuf *n;`
170
171			`MFREE(m, n);`
172			`return (n);`
173			`}`
174
175			`void`
176			`m_freem(m)`
177			`register struct mbuf *m;`
178			`{`
179			`register struct mbuf *n;`
180
181			`if (m == NULL)`
182			`return;`
183			`do {`
184			`MFREE(m, n);`
185			`m = n;`
186			`} while (m);`
187			`}`
188
189			`/*`
190			`* Mbuffer utility routines.`
191			`*/`
192
193			`/*`
194			`* Lesser-used path for M_PREPEND:`
195			`* allocate new mbuf to prepend to chain,`
196			`* copy junk along.`
197			`*/`
198			`struct mbuf *`
199			`m_prepend(m, len, how)`
200			`register struct mbuf *m;`
201			`int len, how;`
202			`{`
203			`struct mbuf *mn;`
204
205			`MGET(mn, how, m->m_type);`
206			`if (mn == (struct mbuf *)NULL) {`
207			`m_freem(m);`
208			`return ((struct mbuf *)NULL);`
209			`}`
210			`if (m->m_flags & M_PKTHDR) {`
211			`M_COPY_PKTHDR(mn, m);`
212			`m->m_flags &= ~M_PKTHDR;`
213			`}`
214			`mn->m_next = m;`
215			`m = mn;`
216			`if (len < MHLEN)`
217			`MH_ALIGN(m, len);`
218			`m->m_len = len;`
219			`return (m);`
220			`}`
221
222			`/*`
223			`* Make a copy of an mbuf chain starting "off0" bytes from the beginning,`
224			`* continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf.`
225			`* The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller.`
226			`*/`
227			`static int MCFail;`
228
229			`struct mbuf *`
230			`m_copym(m, off0, len, wait)`
231			`register struct mbuf *m;`
232			`int off0, wait;`
233			`register int len;`
234			`{`
235			`register struct mbuf n, *np;`
236			`register int off = off0;`
237			`struct mbuf *top;`
238			`int copyhdr = 0;`
239
240			`if (off < 0 \|\| len < 0)`
241			`panic("m_copym");`
242			`if (off == 0 && m->m_flags & M_PKTHDR)`
243			`copyhdr = 1;`
244			`while (off > 0) {`
245			`if (m == 0)`
246			`panic("m_copym");`
247			`if (off < m->m_len)`
248			`break;`
249			`off -= m->m_len;`
250			`m = m->m_next;`
251			`}`
252			`np = &top;`
253			`top = 0;`
254			`while (len > 0) {`
255			`if (m == 0) {`
256			`if (len != M_COPYALL)`
257			`panic("m_copym");`
258			`break;`
259			`}`
260			`MGET(n, wait, m->m_type);`
261			`*np = n;`
262			`if (n == 0)`
263			`goto nospace;`
264			`if (copyhdr) {`
265			`M_COPY_PKTHDR(n, m);`
266			`if (len == M_COPYALL)`
267			`n->m_pkthdr.len -= off0;`
268			`else`
269			`n->m_pkthdr.len = len;`
270			`copyhdr = 0;`
271			`}`
272			`n->m_len = min(len, m->m_len - off);`
273			`if (m->m_flags & M_EXT) {`
274			`n->m_data = m->m_data + off;`
275			`if(!m->m_ext.ext_ref)`
276			`mclrefcnt[mtocl(m->m_ext.ext_buf)]++;`
277			`else`
278			`(*(m->m_ext.ext_ref))(m->m_ext.ext_buf,`
279			`m->m_ext.ext_size);`
280			`n->m_ext = m->m_ext;`
281			`n->m_flags \|= M_EXT;`
282			`} else`
283			`bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t),`
284			`(unsigned)n->m_len);`
285			`if (len != M_COPYALL)`
286			`len -= n->m_len;`
287			`off = 0;`
288			`m = m->m_next;`
289			`np = &n->m_next;`
290			`}`
291			`if (top == 0)`
292			`MCFail++;`
293			`return (top);`
294			`nospace:`
295			`m_freem(top);`
296			`MCFail++;`
297			`return (0);`
298			`}`
299
300			`/*`
301			`* Copy an entire packet, including header (which must be present).`
302			* An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'.
303			`*/`
304			`struct mbuf *`
305			`m_copypacket(m, how)`
306			`struct mbuf *m;`
307			`int how;`
308			`{`
309			`struct mbuf top, n, *o;`
310
311			`MGET(n, how, m->m_type);`
312			`top = n;`
313			`if (!n)`
314			`goto nospace;`
315
316			`M_COPY_PKTHDR(n, m);`
317			`n->m_len = m->m_len;`
318			`if (m->m_flags & M_EXT) {`
319			`n->m_data = m->m_data;`
320			`mclrefcnt[mtocl(m->m_ext.ext_buf)]++;`
321			`n->m_ext = m->m_ext;`
322			`n->m_flags \|= M_EXT;`
323			`} else {`
324			`bcopy(mtod(m, char ), mtod(n, char ), n->m_len);`
325			`}`
326
327			`m = m->m_next;`
328			`while (m) {`
329			`MGET(o, how, m->m_type);`
330			`if (!o)`
331			`goto nospace;`
332
333			`n->m_next = o;`
334			`n = n->m_next;`
335
336			`n->m_len = m->m_len;`
337			`if (m->m_flags & M_EXT) {`
338			`n->m_data = m->m_data;`
339			`mclrefcnt[mtocl(m->m_ext.ext_buf)]++;`
340			`n->m_ext = m->m_ext;`
341			`n->m_flags \|= M_EXT;`
342			`} else {`
343			`bcopy(mtod(m, char ), mtod(n, char ), n->m_len);`
344			`}`
345
346			`m = m->m_next;`
347			`}`
348			`return top;`
349			`nospace:`
350			`m_freem(top);`
351			`MCFail++;`
352			`return 0;`
353			`}`
354
355			`/*`
356			`* Copy data from an mbuf chain starting "off" bytes from the beginning,`
357			`* continuing for "len" bytes, into the indicated buffer.`
358			`*/`
359			`void`
360			`m_copydata(m, off, len, cp)`
361			`register struct mbuf *m;`
362			`register int off;`
363			`register int len;`
364			`caddr_t cp;`
365			`{`
366			`register unsigned count;`
367
368			`if (off < 0 \|\| len < 0)`
369			`panic("m_copydata");`
370			`while (off > 0) {`
371			`if (m == 0)`
372			`panic("m_copydata");`
373			`if (off < m->m_len)`
374			`break;`
375			`off -= m->m_len;`
376			`m = m->m_next;`
377			`}`
378			`while (len > 0) {`
379			`if (m == 0)`
380			`panic("m_copydata");`
381			`count = min(m->m_len - off, len);`
382			`bcopy(mtod(m, caddr_t) + off, cp, count);`
383			`len -= count;`
384			`cp += count;`
385			`off = 0;`
386			`m = m->m_next;`
387			`}`
388			`}`
389
390			`/*`
391			`* Concatenate mbuf chain n to m.`
392			`* Both chains must be of the same type (e.g. MT_DATA).`
393			`* Any m_pkthdr is not updated.`
394			`*/`
395			`void`
396			`m_cat(m, n)`
397			`register struct mbuf m, n;`
398			`{`
399			`while (m->m_next)`
400			`m = m->m_next;`
401			`while (n) {`
402			`if (m->m_flags & M_EXT \|\|`
403			`m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) {`
404			`/* just join the two chains */`
405			`m->m_next = n;`
406			`return;`
407			`}`
408			`/* splat the data from one into the other */`
409			`bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len,`
410			`(u_int)n->m_len);`
411			`m->m_len += n->m_len;`
412			`n = m_free(n);`
413			`}`
414			`}`
415
416			`void`
417			`m_adj(mp, req_len)`
418			`struct mbuf *mp;`
419			`int req_len;`
420			`{`
421			`register int len = req_len;`
422			`register struct mbuf *m;`
423			`register int count;`
424
425			`if ((m = mp) == NULL)`
426			`return;`
427			`if (len >= 0) {`
428			`/*`
429			`* Trim from head.`
430			`*/`
431			`while (m != NULL && len > 0) {`
432			`if (m->m_len <= len) {`
433			`len -= m->m_len;`
434			`m->m_len = 0;`
435			`m = m->m_next;`
436			`} else {`
437			`m->m_len -= len;`
438			`m->m_data += len;`
439			`len = 0;`
440			`}`
441			`}`
442			`m = mp;`
443			`if (mp->m_flags & M_PKTHDR)`
444			`m->m_pkthdr.len -= (req_len - len);`
445			`} else {`
446			`/*`
447			`* Trim from tail. Scan the mbuf chain,`
448			`* calculating its length and finding the last mbuf.`
449			`* If the adjustment only affects this mbuf, then just`
450			`* adjust and return. Otherwise, rescan and truncate`
451			`* after the remaining size.`
452			`*/`
453			`len = -len;`
454			`count = 0;`
455			`for (;;) {`
456			`count += m->m_len;`
457			`if (m->m_next == (struct mbuf *)0)`
458			`break;`
459			`m = m->m_next;`
460			`}`
461			`if (m->m_len >= len) {`
462			`m->m_len -= len;`
463			`if (mp->m_flags & M_PKTHDR)`
464			`mp->m_pkthdr.len -= len;`
465			`return;`
466			`}`
467			`count -= len;`
468			`if (count < 0)`
469			`count = 0;`
470			`/*`
471			`* Correct length for chain is "count".`
472			`* Find the mbuf with last data, adjust its length,`
473			`* and toss data from remaining mbufs on chain.`
474			`*/`
475			`m = mp;`
476			`if (m->m_flags & M_PKTHDR)`
477			`m->m_pkthdr.len = count;`
478			`for (; m; m = m->m_next) {`
479			`if (m->m_len >= count) {`
480			`m->m_len = count;`
481			`break;`
482			`}`
483			`count -= m->m_len;`
484			`}`
485			`while (m->m_next)`
486			`(m = m->m_next) ->m_len = 0;`
487			`}`
488			`}`
489
490			`/*`
491			`* Rearange an mbuf chain so that len bytes are contiguous`
492			`* and in the data area of an mbuf (so that mtod and dtom`
493			`* will work for a structure of size len). Returns the resulting`
494			`* mbuf chain on success, frees it and returns null on failure.`
495			`* If there is room, it will add up to max_protohdr-len extra bytes to the`
496			`* contiguous region in an attempt to avoid being called next time.`
497			`*/`
498			`static int MPFail;`
499
500			`struct mbuf *`
501			`m_pullup(n, len)`
502			`register struct mbuf *n;`
503			`int len;`
504			`{`
505			`register struct mbuf *m;`
506			`register int count;`
507			`int space;`
508
509			`/*`
510			`* If first mbuf has no cluster, and has room for len bytes`
511			`* without shifting current data, pullup into it,`
512			`* otherwise allocate a new mbuf to prepend to the chain.`
513			`*/`
514			`if ((n->m_flags & M_EXT) == 0 &&`
515			`n->m_data + len < &n->m_dat[MLEN] && n->m_next) {`
516			`if (n->m_len >= len)`
517			`return (n);`
518			`m = n;`
519			`n = n->m_next;`
520			`len -= m->m_len;`
521			`} else {`
522			`if (len > MHLEN)`
523			`goto bad;`
524			`MGET(m, M_DONTWAIT, n->m_type);`
525			`if (m == 0)`
526			`goto bad;`
527			`m->m_len = 0;`
528			`if (n->m_flags & M_PKTHDR) {`
529			`M_COPY_PKTHDR(m, n);`
530			`n->m_flags &= ~M_PKTHDR;`
531			`}`
532			`}`
533			`space = &m->m_dat[MLEN] - (m->m_data + m->m_len);`
534			`do {`
535			`count = min(min(max(len, max_protohdr), space), n->m_len);`
536			`bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len,`
537			`(unsigned)count);`
538			`len -= count;`
539			`m->m_len += count;`
540			`n->m_len -= count;`
541			`space -= count;`
542			`if (n->m_len)`
543			`n->m_data += count;`
544			`else`
545			`n = m_free(n);`
546			`} while (len > 0 && n);`
547			`if (len > 0) {`
548			`(void) m_free(m);`
549			`goto bad;`
550			`}`
551			`m->m_next = n;`
552			`return (m);`
553			`bad:`
554			`m_freem(n);`
555			`MPFail++;`
556			`return (0);`
557			`}`
558
559			`/*`
560			`* Partition an mbuf chain in two pieces, returning the tail --`
561			`* all but the first len0 bytes. In case of failure, it returns NULL and`
562			`* attempts to restore the chain to its original state.`
563			`*/`
564			`struct mbuf *`
565			`m_split(m0, len0, wait)`
566			`register struct mbuf *m0;`
567			`int len0, wait;`
568			`{`
569			`register struct mbuf m, n;`
570			`unsigned len = len0, remain;`
571
572			`for (m = m0; m && len > m->m_len; m = m->m_next)`
573			`len -= m->m_len;`
574			`if (m == 0)`
575			`return (0);`
576			`remain = m->m_len - len;`
577			`if (m0->m_flags & M_PKTHDR) {`
578			`MGETHDR(n, wait, m0->m_type);`
579			`if (n == 0)`
580			`return (0);`
581			`n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif;`
582			`n->m_pkthdr.len = m0->m_pkthdr.len - len0;`
583			`m0->m_pkthdr.len = len0;`
584			`if (m->m_flags & M_EXT)`
585			`goto extpacket;`
586			`if (remain > MHLEN) {`
587			`/* m can't be the lead packet */`
588			`MH_ALIGN(n, 0);`
589			`n->m_next = m_split(m, len, wait);`
590			`if (n->m_next == 0) {`
591			`(void) m_free(n);`
592			`return (0);`
593			`} else`
594			`return (n);`
595			`} else`
596			`MH_ALIGN(n, remain);`
597			`} else if (remain == 0) {`
598			`n = m->m_next;`
599			`m->m_next = 0;`
600			`return (n);`
601			`} else {`
602			`MGET(n, wait, m->m_type);`
603			`if (n == 0)`
604			`return (0);`
605			`M_ALIGN(n, remain);`
606			`}`
607			`extpacket:`
608			`if (m->m_flags & M_EXT) {`
609			`n->m_flags \|= M_EXT;`
610			`n->m_ext = m->m_ext;`
611			`if(!m->m_ext.ext_ref)`
612			`mclrefcnt[mtocl(m->m_ext.ext_buf)]++;`
613			`else`
614			`(*(m->m_ext.ext_ref))(m->m_ext.ext_buf,`
615			`m->m_ext.ext_size);`
616			`m->m_ext.ext_size = 0; /* For Accounting XXXXXX danger */`
617			`n->m_data = m->m_data + len;`
618			`} else {`
619			`bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain);`
620			`}`
621			`n->m_len = remain;`
622			`m->m_len = len;`
623			`n->m_next = m->m_next;`
624			`m->m_next = 0;`
625			`return (n);`
626			`}`
627			`/*`
628			`* Routine to copy from device local memory into mbufs.`
629			`*/`
630			`struct mbuf *`
631			`m_devget(buf, totlen, off0, ifp, copy)`
632			`char *buf;`
633			`int totlen, off0;`
634			`struct ifnet *ifp;`
635			`void (copy) __P((char from, caddr_t to, u_int len));`
636			`{`
637			`register struct mbuf *m;`
638			`struct mbuf top = 0, *mp = &top;`
639			`register int off = off0, len;`
640			`register char *cp;`
641			`char *epkt;`
642
643			`cp = buf;`
644			`epkt = cp + totlen;`
645			`if (off) {`
646			`cp += off + 2 * sizeof(u_short);`
647			`totlen -= 2 * sizeof(u_short);`
648			`}`
649			`MGETHDR(m, M_DONTWAIT, MT_DATA);`
650			`if (m == 0)`
651			`return (0);`
652			`m->m_pkthdr.rcvif = ifp;`
653			`m->m_pkthdr.len = totlen;`
654			`m->m_len = MHLEN;`
655
656			`while (totlen > 0) {`
657			`if (top) {`
658			`MGET(m, M_DONTWAIT, MT_DATA);`
659			`if (m == 0) {`
660			`m_freem(top);`
661			`return (0);`
662			`}`
663			`m->m_len = MLEN;`
664			`}`
665			`len = min(totlen, epkt - cp);`
666			`if (len >= MINCLSIZE) {`
667			`MCLGET(m, M_DONTWAIT);`
668			`if (m->m_flags & M_EXT)`
669			`m->m_len = len = min(len, MCLBYTES);`
670			`else`
671			`len = m->m_len;`
672			`} else {`
673			`/*`
674			`* Place initial small packet/header at end of mbuf.`
675			`*/`
676			`if (len < m->m_len) {`
677			`if (top == 0 && len + max_linkhdr <= m->m_len)`
678			`m->m_data += max_linkhdr;`
679			`m->m_len = len;`
680			`} else`
681			`len = m->m_len;`
682			`}`
683			`if (copy)`
684			`copy(cp, mtod(m, caddr_t), (unsigned)len);`
685			`else`
686			`bcopy(cp, mtod(m, caddr_t), (unsigned)len);`
687			`cp += len;`
688			`*mp = m;`
689			`mp = &m->m_next;`
690			`totlen -= len;`
691			`if (cp == epkt)`
692			`cp = buf;`
693			`}`
694			`return (top);`
695			`}`
696
697			`/*`
698			`* Copy data from a buffer back into the indicated mbuf chain,`
699			`* starting "off" bytes from the beginning, extending the mbuf`
700			`* chain if necessary.`
701			`*/`
702			`void`
703			`m_copyback(m0, off, len, cp)`
704			`struct mbuf *m0;`
705			`register int off;`
706			`register int len;`
707			`caddr_t cp;`
708			`{`
709			`register int mlen;`
710			`register struct mbuf m = m0, n;`
711			`int totlen = 0;`
712
713			`if (m0 == 0)`
714			`return;`
715			`while (off > (mlen = m->m_len)) {`
716			`off -= mlen;`
717			`totlen += mlen;`
718			`if (m->m_next == 0) {`
719			`n = m_getclr(M_DONTWAIT, m->m_type);`
720			`if (n == 0)`
721			`goto out;`
722			`n->m_len = min(MLEN, len + off);`
723			`m->m_next = n;`
724			`}`
725			`m = m->m_next;`
726			`}`
727			`while (len > 0) {`
728			`mlen = min (m->m_len - off, len);`
729			`bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen);`
730			`cp += mlen;`
731			`len -= mlen;`
732			`mlen += off;`
733			`off = 0;`
734			`totlen += mlen;`
735			`if (len == 0)`
736			`break;`
737			`if (m->m_next == 0) {`
738			`n = m_get(M_DONTWAIT, m->m_type);`
739			`if (n == 0)`
740			`break;`
741			`n->m_len = min(MLEN, len);`
742			`m->m_next = n;`
743			`}`
744			`m = m->m_next;`
745			`}`
746			`out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen))`
747			`m->m_pkthdr.len = totlen;`
748			`}`