af7615d39a
into uipc_mbuf.c. This reduces three sets of identical tunable code to one set, and puts the initialisation with the mbuf code proper. Make NMBUFs tunable as well. Move the nmbclusters sysctl here as well. Move the initialisation of maxsockets from param.c to uipc_socket2.c, next to its corresponding sysctl. Use the new tunable macros for the kern.vm.kmem.size tunable (this should have been in a separate commit, whoops).
957 lines
20 KiB
C
957 lines
20 KiB
C
/*
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* Copyright (c) 1982, 1986, 1988, 1991, 1993
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* The Regents of the University of California. All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. All advertising materials mentioning features or use of this software
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* must display the following acknowledgement:
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* This product includes software developed by the University of
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* California, Berkeley and its contributors.
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* 4. Neither the name of the University nor the names of its contributors
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*
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* @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94
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* $Id: uipc_mbuf.c,v 1.40 1999/07/01 13:21:39 peter Exp $
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*/
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#include "opt_param.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/malloc.h>
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#include <sys/mbuf.h>
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#include <sys/kernel.h>
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#include <sys/sysctl.h>
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#include <sys/domain.h>
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#include <sys/protosw.h>
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#include <vm/vm.h>
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#include <vm/vm_kern.h>
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#include <vm/vm_extern.h>
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static void mbinit __P((void *));
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SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbinit, NULL)
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struct mbuf *mbutl;
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char *mclrefcnt;
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struct mbstat mbstat;
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struct mbuf *mmbfree;
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union mcluster *mclfree;
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int max_linkhdr;
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int max_protohdr;
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int max_hdr;
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int max_datalen;
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int nmbclusters;
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int nmbufs;
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SYSCTL_DECL(_kern_ipc);
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SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RW,
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&max_linkhdr, 0, "");
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SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RW,
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&max_protohdr, 0, "");
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SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RW, &max_hdr, 0, "");
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SYSCTL_INT(_kern_ipc, KIPC_MAX_DATALEN, max_datalen, CTLFLAG_RW,
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&max_datalen, 0, "");
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SYSCTL_STRUCT(_kern_ipc, KIPC_MBSTAT, mbstat, CTLFLAG_RW, &mbstat, mbstat, "");
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SYSCTL_INT(_kern_ipc, KIPC_NMBCLUSTERS, nmbclusters, CTLFLAG_RD,
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&nmbclusters, 0, "Maximum number of mbuf clusters avaliable");
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#ifndef NMBCLUSTERS
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#define NMBCLUSTERS (512 + MAXUSERS * 16)
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#endif
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TUNABLE_INT_DECL("kern.ipc.nmbclusters", NMBCLUSTERS, nmbclusters);
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TUNABLE_INT_DECL("kern.ipc.nmbufs", NMBCLUSTERS * 4, nmbufs); /* XXX fixup? */
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static void m_reclaim __P((void));
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/* "number of clusters of pages" */
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#define NCL_INIT 1
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#define NMB_INIT 16
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/* ARGSUSED*/
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static void
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mbinit(dummy)
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void *dummy;
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{
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int s;
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mmbfree = NULL; mclfree = NULL;
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mbstat.m_msize = MSIZE;
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mbstat.m_mclbytes = MCLBYTES;
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mbstat.m_minclsize = MINCLSIZE;
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mbstat.m_mlen = MLEN;
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mbstat.m_mhlen = MHLEN;
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s = splimp();
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if (m_mballoc(NMB_INIT, M_DONTWAIT) == 0)
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goto bad;
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#if MCLBYTES <= PAGE_SIZE
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if (m_clalloc(NCL_INIT, M_DONTWAIT) == 0)
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goto bad;
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#else
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/* It's OK to call contigmalloc in this context. */
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if (m_clalloc(16, M_WAIT) == 0)
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goto bad;
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#endif
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splx(s);
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return;
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bad:
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panic("mbinit");
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}
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/*
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* Allocate at least nmb mbufs and place on mbuf free list.
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* Must be called at splimp.
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*/
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/* ARGSUSED */
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int
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m_mballoc(nmb, how)
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register int nmb;
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int how;
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{
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register caddr_t p;
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register int i;
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int nbytes;
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/* Once we run out of map space, it will be impossible to get
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* any more (nothing is ever freed back to the map) (XXX which
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* is dumb). (however you are not dead as m_reclaim might
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* still be able to free a substantial amount of space).
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*/
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if (mb_map_full)
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return (0);
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nbytes = round_page(nmb * MSIZE);
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p = (caddr_t)kmem_malloc(mb_map, nbytes, M_NOWAIT);
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if (p == 0 && how == M_WAIT) {
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mbstat.m_wait++;
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p = (caddr_t)kmem_malloc(mb_map, nbytes, M_WAITOK);
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}
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/*
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* Either the map is now full, or `how' is M_NOWAIT and there
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* are no pages left.
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*/
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if (p == NULL)
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return (0);
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nmb = nbytes / MSIZE;
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for (i = 0; i < nmb; i++) {
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((struct mbuf *)p)->m_next = mmbfree;
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mmbfree = (struct mbuf *)p;
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p += MSIZE;
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}
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mbstat.m_mbufs += nmb;
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return (1);
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}
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#if MCLBYTES > PAGE_SIZE
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static int i_want_my_mcl;
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static void
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kproc_mclalloc(void)
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{
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int status;
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while (1) {
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tsleep(&i_want_my_mcl, PVM, "mclalloc", 0);
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for (; i_want_my_mcl; i_want_my_mcl--) {
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if (m_clalloc(1, M_WAIT) == 0)
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printf("m_clalloc failed even in process context!\n");
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}
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}
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}
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static struct proc *mclallocproc;
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static struct kproc_desc mclalloc_kp = {
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"mclalloc",
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kproc_mclalloc,
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&mclallocproc
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};
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SYSINIT(mclallocproc, SI_SUB_KTHREAD_UPDATE, SI_ORDER_ANY, kproc_start,
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&mclalloc_kp);
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#endif
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/*
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* Allocate some number of mbuf clusters
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* and place on cluster free list.
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* Must be called at splimp.
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*/
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/* ARGSUSED */
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int
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m_clalloc(ncl, how)
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register int ncl;
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int how;
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{
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register caddr_t p;
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register int i;
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int npg;
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/*
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* Once we run out of map space, it will be impossible
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* to get any more (nothing is ever freed back to the
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* map).
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*/
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if (mb_map_full) {
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mbstat.m_drops++;
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return (0);
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}
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#if MCLBYTES > PAGE_SIZE
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if (how != M_WAIT) {
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i_want_my_mcl += ncl;
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wakeup(&i_want_my_mcl);
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mbstat.m_wait++;
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p = 0;
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} else {
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p = contigmalloc1(MCLBYTES * ncl, M_DEVBUF, M_WAITOK, 0ul,
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~0ul, PAGE_SIZE, 0, mb_map);
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}
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#else
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npg = ncl;
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p = (caddr_t)kmem_malloc(mb_map, ctob(npg),
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how != M_WAIT ? M_NOWAIT : M_WAITOK);
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ncl = ncl * PAGE_SIZE / MCLBYTES;
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#endif
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/*
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* Either the map is now full, or `how' is M_NOWAIT and there
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* are no pages left.
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*/
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if (p == NULL) {
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mbstat.m_drops++;
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return (0);
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}
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for (i = 0; i < ncl; i++) {
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((union mcluster *)p)->mcl_next = mclfree;
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mclfree = (union mcluster *)p;
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p += MCLBYTES;
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mbstat.m_clfree++;
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}
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mbstat.m_clusters += ncl;
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return (1);
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}
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/*
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* When MGET fails, ask protocols to free space when short of memory,
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* then re-attempt to allocate an mbuf.
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*/
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struct mbuf *
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m_retry(i, t)
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int i, t;
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{
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register struct mbuf *m;
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/*
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* Must only do the reclaim if not in an interrupt context.
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*/
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if (i == M_WAIT)
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m_reclaim();
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#define m_retry(i, t) (struct mbuf *)0
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MGET(m, i, t);
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#undef m_retry
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if (m != NULL) {
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mbstat.m_wait++;
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} else {
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if (i == M_DONTWAIT)
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mbstat.m_drops++;
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else
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panic("Out of mbuf clusters");
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}
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return (m);
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}
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/*
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* As above; retry an MGETHDR.
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*/
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struct mbuf *
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m_retryhdr(i, t)
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int i, t;
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{
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register struct mbuf *m;
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/*
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* Must only do the reclaim if not in an interrupt context.
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*/
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if (i == M_WAIT)
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m_reclaim();
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#define m_retryhdr(i, t) (struct mbuf *)0
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MGETHDR(m, i, t);
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#undef m_retryhdr
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if (m != NULL) {
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mbstat.m_wait++;
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} else {
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if (i == M_DONTWAIT)
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mbstat.m_drops++;
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else
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panic("Out of mbuf clusters");
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}
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return (m);
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}
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static void
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m_reclaim()
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{
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register struct domain *dp;
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register struct protosw *pr;
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int s = splimp();
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for (dp = domains; dp; dp = dp->dom_next)
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for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++)
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if (pr->pr_drain)
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(*pr->pr_drain)();
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splx(s);
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mbstat.m_drain++;
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}
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/*
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* Space allocation routines.
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* These are also available as macros
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* for critical paths.
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*/
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struct mbuf *
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m_get(how, type)
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int how, type;
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{
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register struct mbuf *m;
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MGET(m, how, type);
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return (m);
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}
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struct mbuf *
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m_gethdr(how, type)
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int how, type;
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{
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register struct mbuf *m;
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MGETHDR(m, how, type);
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return (m);
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}
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struct mbuf *
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m_getclr(how, type)
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int how, type;
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{
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register struct mbuf *m;
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MGET(m, how, type);
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if (m == 0)
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return (0);
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bzero(mtod(m, caddr_t), MLEN);
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return (m);
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}
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struct mbuf *
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m_free(m)
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struct mbuf *m;
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{
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register struct mbuf *n;
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MFREE(m, n);
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return (n);
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}
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void
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m_freem(m)
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register struct mbuf *m;
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{
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register struct mbuf *n;
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if (m == NULL)
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return;
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do {
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MFREE(m, n);
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m = n;
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} while (m);
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}
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/*
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* Mbuffer utility routines.
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*/
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/*
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* Lesser-used path for M_PREPEND:
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* allocate new mbuf to prepend to chain,
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* copy junk along.
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*/
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struct mbuf *
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m_prepend(m, len, how)
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register struct mbuf *m;
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int len, how;
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{
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struct mbuf *mn;
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MGET(mn, how, m->m_type);
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if (mn == (struct mbuf *)NULL) {
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m_freem(m);
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return ((struct mbuf *)NULL);
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}
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if (m->m_flags & M_PKTHDR) {
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M_COPY_PKTHDR(mn, m);
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m->m_flags &= ~M_PKTHDR;
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}
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mn->m_next = m;
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m = mn;
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if (len < MHLEN)
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MH_ALIGN(m, len);
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m->m_len = len;
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return (m);
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}
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|
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/*
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* Make a copy of an mbuf chain starting "off0" bytes from the beginning,
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* continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf.
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* The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller.
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*/
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#define MCFail (mbstat.m_mcfail)
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struct mbuf *
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m_copym(m, off0, len, wait)
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register struct mbuf *m;
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int off0, wait;
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register int len;
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{
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register struct mbuf *n, **np;
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register int off = off0;
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struct mbuf *top;
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int copyhdr = 0;
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|
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if (off < 0 || len < 0)
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panic("m_copym");
|
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if (off == 0 && m->m_flags & M_PKTHDR)
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copyhdr = 1;
|
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while (off > 0) {
|
|
if (m == 0)
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panic("m_copym");
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if (off < m->m_len)
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break;
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off -= m->m_len;
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m = m->m_next;
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}
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np = ⊤
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top = 0;
|
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while (len > 0) {
|
|
if (m == 0) {
|
|
if (len != M_COPYALL)
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|
panic("m_copym");
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break;
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}
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MGET(n, wait, m->m_type);
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|
*np = n;
|
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if (n == 0)
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goto nospace;
|
|
if (copyhdr) {
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M_COPY_PKTHDR(n, m);
|
|
if (len == M_COPYALL)
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n->m_pkthdr.len -= off0;
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|
else
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n->m_pkthdr.len = len;
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|
copyhdr = 0;
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}
|
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n->m_len = min(len, m->m_len - off);
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if (m->m_flags & M_EXT) {
|
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n->m_data = m->m_data + off;
|
|
if(!m->m_ext.ext_ref)
|
|
mclrefcnt[mtocl(m->m_ext.ext_buf)]++;
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|
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;
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|
} else
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bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t),
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(unsigned)n->m_len);
|
|
if (len != M_COPYALL)
|
|
len -= n->m_len;
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|
off = 0;
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m = m->m_next;
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|
np = &n->m_next;
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|
}
|
|
if (top == 0)
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|
MCFail++;
|
|
return (top);
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|
nospace:
|
|
m_freem(top);
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|
MCFail++;
|
|
return (0);
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|
}
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|
|
/*
|
|
* Copy an entire packet, including header (which must be present).
|
|
* An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'.
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|
*/
|
|
struct mbuf *
|
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m_copypacket(m, how)
|
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struct mbuf *m;
|
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int how;
|
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{
|
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struct mbuf *top, *n, *o;
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|
|
MGET(n, how, m->m_type);
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|
top = n;
|
|
if (!n)
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goto nospace;
|
|
|
|
M_COPY_PKTHDR(n, m);
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n->m_len = m->m_len;
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if (m->m_flags & M_EXT) {
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n->m_data = m->m_data;
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|
if(!m->m_ext.ext_ref)
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mclrefcnt[mtocl(m->m_ext.ext_buf)]++;
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|
else
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(*(m->m_ext.ext_ref))(m->m_ext.ext_buf,
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m->m_ext.ext_size);
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|
n->m_ext = m->m_ext;
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n->m_flags |= M_EXT;
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|
} else {
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bcopy(mtod(m, char *), mtod(n, char *), n->m_len);
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}
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|
|
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;
|
|
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, 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.
|
|
*/
|
|
#define MPFail (mbstat.m_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 = ⊤
|
|
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;
|
|
}
|