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uipc_mbuf.c revision 1.203
      1  1.203      maxv /*	$NetBSD: uipc_mbuf.c,v 1.203 2018/04/27 07:41:58 maxv Exp $	*/
      2   1.42   thorpej 
      3  1.177      maxv /*
      4   1.53   thorpej  * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc.
      5   1.42   thorpej  * All rights reserved.
      6   1.42   thorpej  *
      7   1.42   thorpej  * This code is derived from software contributed to The NetBSD Foundation
      8   1.42   thorpej  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9   1.42   thorpej  * NASA Ames Research Center.
     10   1.42   thorpej  *
     11   1.42   thorpej  * Redistribution and use in source and binary forms, with or without
     12   1.42   thorpej  * modification, are permitted provided that the following conditions
     13   1.42   thorpej  * are met:
     14   1.42   thorpej  * 1. Redistributions of source code must retain the above copyright
     15   1.42   thorpej  *    notice, this list of conditions and the following disclaimer.
     16   1.42   thorpej  * 2. Redistributions in binary form must reproduce the above copyright
     17   1.42   thorpej  *    notice, this list of conditions and the following disclaimer in the
     18   1.42   thorpej  *    documentation and/or other materials provided with the distribution.
     19   1.42   thorpej  *
     20   1.42   thorpej  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     21   1.42   thorpej  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     22   1.42   thorpej  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     23   1.42   thorpej  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     24   1.42   thorpej  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     25   1.42   thorpej  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     26   1.42   thorpej  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     27   1.42   thorpej  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     28   1.42   thorpej  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     29   1.42   thorpej  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     30   1.42   thorpej  * POSSIBILITY OF SUCH DAMAGE.
     31   1.42   thorpej  */
     32   1.10       cgd 
     33    1.1       cgd /*
     34    1.9   mycroft  * Copyright (c) 1982, 1986, 1988, 1991, 1993
     35    1.9   mycroft  *	The Regents of the University of California.  All rights reserved.
     36    1.1       cgd  *
     37    1.1       cgd  * Redistribution and use in source and binary forms, with or without
     38    1.1       cgd  * modification, are permitted provided that the following conditions
     39    1.1       cgd  * are met:
     40    1.1       cgd  * 1. Redistributions of source code must retain the above copyright
     41    1.1       cgd  *    notice, this list of conditions and the following disclaimer.
     42    1.1       cgd  * 2. Redistributions in binary form must reproduce the above copyright
     43    1.1       cgd  *    notice, this list of conditions and the following disclaimer in the
     44    1.1       cgd  *    documentation and/or other materials provided with the distribution.
     45   1.70       agc  * 3. Neither the name of the University nor the names of its contributors
     46    1.1       cgd  *    may be used to endorse or promote products derived from this software
     47    1.1       cgd  *    without specific prior written permission.
     48    1.1       cgd  *
     49    1.1       cgd  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     50    1.1       cgd  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     51    1.1       cgd  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     52    1.1       cgd  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     53    1.1       cgd  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     54    1.1       cgd  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     55    1.1       cgd  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     56    1.1       cgd  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     57    1.1       cgd  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     58    1.1       cgd  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     59    1.1       cgd  * SUCH DAMAGE.
     60    1.1       cgd  *
     61   1.26      fvdl  *	@(#)uipc_mbuf.c	8.4 (Berkeley) 2/14/95
     62    1.1       cgd  */
     63   1.56     lukem 
     64   1.56     lukem #include <sys/cdefs.h>
     65  1.203      maxv __KERNEL_RCSID(0, "$NetBSD: uipc_mbuf.c,v 1.203 2018/04/27 07:41:58 maxv Exp $");
     66   1.69    martin 
     67  1.163     pooka #ifdef _KERNEL_OPT
     68   1.69    martin #include "opt_mbuftrace.h"
     69  1.133     joerg #include "opt_nmbclusters.h"
     70  1.105      yamt #include "opt_ddb.h"
     71  1.163     pooka #endif
     72   1.24       mrg 
     73    1.6   mycroft #include <sys/param.h>
     74    1.6   mycroft #include <sys/systm.h>
     75  1.125      yamt #include <sys/atomic.h>
     76  1.124      yamt #include <sys/cpu.h>
     77    1.6   mycroft #include <sys/proc.h>
     78    1.6   mycroft #include <sys/mbuf.h>
     79    1.6   mycroft #include <sys/kernel.h>
     80    1.6   mycroft #include <sys/syslog.h>
     81    1.6   mycroft #include <sys/domain.h>
     82    1.6   mycroft #include <sys/protosw.h>
     83  1.124      yamt #include <sys/percpu.h>
     84   1.28   thorpej #include <sys/pool.h>
     85   1.27      matt #include <sys/socket.h>
     86   1.55    simonb #include <sys/sysctl.h>
     87   1.55    simonb 
     88   1.27      matt #include <net/if.h>
     89   1.14  christos 
     90  1.122        ad pool_cache_t mb_cache;	/* mbuf cache */
     91  1.122        ad pool_cache_t mcl_cache;	/* mbuf cluster cache */
     92   1.53   thorpej 
     93   1.18   thorpej struct mbstat mbstat;
     94  1.199      maxv int max_linkhdr;
     95  1.199      maxv int max_protohdr;
     96  1.199      maxv int max_hdr;
     97  1.199      maxv int max_datalen;
     98   1.18   thorpej 
     99  1.203      maxv static void mb_drain(void *, int);
    100   1.65   thorpej static int mb_ctor(void *, void *, int);
    101   1.65   thorpej 
    102  1.199      maxv static void sysctl_kern_mbuf_setup(void);
    103  1.129     pooka 
    104  1.129     pooka static struct sysctllog *mbuf_sysctllog;
    105  1.129     pooka 
    106  1.195      maxv static struct mbuf *m_copy_internal(struct mbuf *, int, int, int, bool);
    107  1.195      maxv static struct mbuf *m_split_internal(struct mbuf *, int, int, bool);
    108  1.196      maxv static int m_copyback_internal(struct mbuf **, int, int, const void *,
    109  1.196      maxv     int, int);
    110   1.85      yamt 
    111  1.196      maxv /* Flags for m_copyback_internal. */
    112  1.196      maxv #define	CB_COPYBACK	0x0001	/* copyback from cp */
    113  1.196      maxv #define	CB_PRESERVE	0x0002	/* preserve original data */
    114  1.196      maxv #define	CB_COW		0x0004	/* do copy-on-write */
    115  1.196      maxv #define	CB_EXTEND	0x0008	/* extend chain */
    116   1.28   thorpej 
    117  1.103   thorpej static const char mclpool_warnmsg[] =
    118  1.133     joerg     "WARNING: mclpool limit reached; increase kern.mbuf.nmbclusters";
    119   1.63   thorpej 
    120   1.63   thorpej MALLOC_DEFINE(M_MBUF, "mbuf", "mbuf");
    121   1.42   thorpej 
    122  1.124      yamt static percpu_t *mbstat_percpu;
    123  1.124      yamt 
    124   1.64      matt #ifdef MBUFTRACE
    125   1.64      matt struct mownerhead mowners = LIST_HEAD_INITIALIZER(mowners);
    126   1.64      matt struct mowner unknown_mowners[] = {
    127  1.114    dogcow 	MOWNER_INIT("unknown", "free"),
    128  1.114    dogcow 	MOWNER_INIT("unknown", "data"),
    129  1.114    dogcow 	MOWNER_INIT("unknown", "header"),
    130  1.114    dogcow 	MOWNER_INIT("unknown", "soname"),
    131  1.114    dogcow 	MOWNER_INIT("unknown", "soopts"),
    132  1.114    dogcow 	MOWNER_INIT("unknown", "ftable"),
    133  1.114    dogcow 	MOWNER_INIT("unknown", "control"),
    134  1.114    dogcow 	MOWNER_INIT("unknown", "oobdata"),
    135   1.64      matt };
    136  1.114    dogcow struct mowner revoked_mowner = MOWNER_INIT("revoked", "");
    137   1.64      matt #endif
    138   1.64      matt 
    139  1.125      yamt #define	MEXT_ISEMBEDDED(m) ((m)->m_ext_ref == (m))
    140  1.125      yamt 
    141  1.125      yamt #define	MCLADDREFERENCE(o, n)						\
    142  1.125      yamt do {									\
    143  1.125      yamt 	KASSERT(((o)->m_flags & M_EXT) != 0);				\
    144  1.125      yamt 	KASSERT(((n)->m_flags & M_EXT) == 0);				\
    145  1.125      yamt 	KASSERT((o)->m_ext.ext_refcnt >= 1);				\
    146  1.125      yamt 	(n)->m_flags |= ((o)->m_flags & M_EXTCOPYFLAGS);		\
    147  1.125      yamt 	atomic_inc_uint(&(o)->m_ext.ext_refcnt);			\
    148  1.125      yamt 	(n)->m_ext_ref = (o)->m_ext_ref;				\
    149  1.125      yamt 	mowner_ref((n), (n)->m_flags);					\
    150  1.125      yamt 	MCLREFDEBUGN((n), __FILE__, __LINE__);				\
    151  1.125      yamt } while (/* CONSTCOND */ 0)
    152  1.125      yamt 
    153  1.133     joerg static int
    154  1.133     joerg nmbclusters_limit(void)
    155  1.133     joerg {
    156  1.136     pooka #if defined(PMAP_MAP_POOLPAGE)
    157  1.147      para 	/* direct mapping, doesn't use space in kmem_arena */
    158  1.133     joerg 	vsize_t max_size = physmem / 4;
    159  1.133     joerg #else
    160  1.145      para 	vsize_t max_size = MIN(physmem / 4, nkmempages / 4);
    161  1.133     joerg #endif
    162  1.133     joerg 
    163  1.133     joerg 	max_size = max_size * PAGE_SIZE / MCLBYTES;
    164  1.133     joerg #ifdef NMBCLUSTERS_MAX
    165  1.133     joerg 	max_size = MIN(max_size, NMBCLUSTERS_MAX);
    166  1.133     joerg #endif
    167  1.133     joerg 
    168  1.133     joerg #ifdef NMBCLUSTERS
    169  1.133     joerg 	return MIN(max_size, NMBCLUSTERS);
    170  1.133     joerg #else
    171  1.133     joerg 	return max_size;
    172  1.133     joerg #endif
    173  1.133     joerg }
    174  1.133     joerg 
    175   1.28   thorpej /*
    176   1.68    simonb  * Initialize the mbuf allocator.
    177   1.28   thorpej  */
    178    1.4       jtc void
    179   1.62   thorpej mbinit(void)
    180    1.1       cgd {
    181   1.65   thorpej 
    182  1.128      matt 	CTASSERT(sizeof(struct _m_ext) <= MHLEN);
    183  1.128      matt 	CTASSERT(sizeof(struct mbuf) == MSIZE);
    184   1.65   thorpej 
    185  1.129     pooka 	sysctl_kern_mbuf_setup();
    186  1.129     pooka 
    187  1.122        ad 	mb_cache = pool_cache_init(msize, 0, 0, 0, "mbpl",
    188  1.122        ad 	    NULL, IPL_VM, mb_ctor, NULL, NULL);
    189  1.122        ad 	KASSERT(mb_cache != NULL);
    190  1.122        ad 
    191  1.135     rmind 	mcl_cache = pool_cache_init(mclbytes, 0, 0, 0, "mclpl", NULL,
    192  1.135     rmind 	    IPL_VM, NULL, NULL, NULL);
    193  1.122        ad 	KASSERT(mcl_cache != NULL);
    194   1.59   thorpej 
    195  1.203      maxv 	pool_cache_set_drain_hook(mb_cache, mb_drain, NULL);
    196  1.203      maxv 	pool_cache_set_drain_hook(mcl_cache, mb_drain, NULL);
    197   1.37   thorpej 
    198   1.37   thorpej 	/*
    199  1.133     joerg 	 * Set an arbitrary default limit on the number of mbuf clusters.
    200  1.133     joerg 	 */
    201  1.133     joerg #ifdef NMBCLUSTERS
    202  1.133     joerg 	nmbclusters = nmbclusters_limit();
    203  1.133     joerg #else
    204  1.133     joerg 	nmbclusters = MAX(1024,
    205  1.133     joerg 	    (vsize_t)physmem * PAGE_SIZE / MCLBYTES / 16);
    206  1.133     joerg 	nmbclusters = MIN(nmbclusters, nmbclusters_limit());
    207  1.133     joerg #endif
    208  1.133     joerg 
    209  1.133     joerg 	/*
    210   1.39   thorpej 	 * Set the hard limit on the mclpool to the number of
    211   1.39   thorpej 	 * mbuf clusters the kernel is to support.  Log the limit
    212   1.39   thorpej 	 * reached message max once a minute.
    213   1.39   thorpej 	 */
    214  1.122        ad 	pool_cache_sethardlimit(mcl_cache, nmbclusters, mclpool_warnmsg, 60);
    215   1.42   thorpej 
    216  1.124      yamt 	mbstat_percpu = percpu_alloc(sizeof(struct mbstat_cpu));
    217  1.124      yamt 
    218   1.39   thorpej 	/*
    219   1.42   thorpej 	 * Set a low water mark for both mbufs and clusters.  This should
    220   1.42   thorpej 	 * help ensure that they can be allocated in a memory starvation
    221   1.42   thorpej 	 * situation.  This is important for e.g. diskless systems which
    222   1.42   thorpej 	 * must allocate mbufs in order for the pagedaemon to clean pages.
    223   1.37   thorpej 	 */
    224  1.122        ad 	pool_cache_setlowat(mb_cache, mblowat);
    225  1.122        ad 	pool_cache_setlowat(mcl_cache, mcllowat);
    226   1.64      matt 
    227   1.64      matt #ifdef MBUFTRACE
    228   1.64      matt 	{
    229   1.64      matt 		/*
    230   1.64      matt 		 * Attach the unknown mowners.
    231   1.64      matt 		 */
    232   1.64      matt 		int i;
    233   1.64      matt 		MOWNER_ATTACH(&revoked_mowner);
    234   1.64      matt 		for (i = sizeof(unknown_mowners)/sizeof(unknown_mowners[0]);
    235   1.64      matt 		     i-- > 0; )
    236   1.64      matt 			MOWNER_ATTACH(&unknown_mowners[i]);
    237   1.64      matt 	}
    238   1.64      matt #endif
    239   1.42   thorpej }
    240   1.42   thorpej 
    241  1.203      maxv static void
    242  1.203      maxv mb_drain(void *arg, int flags)
    243  1.203      maxv {
    244  1.203      maxv 	struct domain *dp;
    245  1.203      maxv 	const struct protosw *pr;
    246  1.203      maxv 	struct ifnet *ifp;
    247  1.203      maxv 	int s;
    248  1.203      maxv 
    249  1.203      maxv 	KERNEL_LOCK(1, NULL);
    250  1.203      maxv 	s = splvm();
    251  1.203      maxv 	DOMAIN_FOREACH(dp) {
    252  1.203      maxv 		for (pr = dp->dom_protosw;
    253  1.203      maxv 		     pr < dp->dom_protoswNPROTOSW; pr++)
    254  1.203      maxv 			if (pr->pr_drain)
    255  1.203      maxv 				(*pr->pr_drain)();
    256  1.203      maxv 	}
    257  1.203      maxv 	/* XXX we cannot use psref in H/W interrupt */
    258  1.203      maxv 	if (!cpu_intr_p()) {
    259  1.203      maxv 		int bound = curlwp_bind();
    260  1.203      maxv 		IFNET_READER_FOREACH(ifp) {
    261  1.203      maxv 			struct psref psref;
    262  1.203      maxv 
    263  1.203      maxv 			if_acquire(ifp, &psref);
    264  1.203      maxv 
    265  1.203      maxv 			if (ifp->if_drain)
    266  1.203      maxv 				(*ifp->if_drain)(ifp);
    267  1.203      maxv 
    268  1.203      maxv 			if_release(ifp, &psref);
    269  1.203      maxv 		}
    270  1.203      maxv 		curlwp_bindx(bound);
    271  1.203      maxv 	}
    272  1.203      maxv 	splx(s);
    273  1.203      maxv 	mbstat.m_drain++;
    274  1.203      maxv 	KERNEL_UNLOCK_ONE(NULL);
    275  1.203      maxv }
    276  1.203      maxv 
    277   1.75    atatat /*
    278  1.133     joerg  * sysctl helper routine for the kern.mbuf subtree.
    279  1.133     joerg  * nmbclusters, mblowat and mcllowat need range
    280   1.75    atatat  * checking and pool tweaking after being reset.
    281   1.75    atatat  */
    282   1.75    atatat static int
    283   1.75    atatat sysctl_kern_mbuf(SYSCTLFN_ARGS)
    284   1.42   thorpej {
    285   1.42   thorpej 	int error, newval;
    286   1.75    atatat 	struct sysctlnode node;
    287   1.42   thorpej 
    288   1.75    atatat 	node = *rnode;
    289   1.75    atatat 	node.sysctl_data = &newval;
    290   1.75    atatat 	switch (rnode->sysctl_num) {
    291   1.42   thorpej 	case MBUF_NMBCLUSTERS:
    292   1.42   thorpej 	case MBUF_MBLOWAT:
    293   1.42   thorpej 	case MBUF_MCLLOWAT:
    294   1.75    atatat 		newval = *(int*)rnode->sysctl_data;
    295   1.75    atatat 		break;
    296   1.75    atatat 	default:
    297  1.199      maxv 		return EOPNOTSUPP;
    298   1.75    atatat 	}
    299   1.75    atatat 
    300   1.75    atatat 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
    301   1.75    atatat 	if (error || newp == NULL)
    302  1.199      maxv 		return error;
    303   1.75    atatat 	if (newval < 0)
    304  1.199      maxv 		return EINVAL;
    305   1.75    atatat 
    306   1.75    atatat 	switch (node.sysctl_num) {
    307   1.75    atatat 	case MBUF_NMBCLUSTERS:
    308   1.75    atatat 		if (newval < nmbclusters)
    309  1.199      maxv 			return EINVAL;
    310  1.133     joerg 		if (newval > nmbclusters_limit())
    311  1.199      maxv 			return EINVAL;
    312   1.75    atatat 		nmbclusters = newval;
    313  1.122        ad 		pool_cache_sethardlimit(mcl_cache, nmbclusters,
    314  1.122        ad 		    mclpool_warnmsg, 60);
    315   1.75    atatat 		break;
    316   1.75    atatat 	case MBUF_MBLOWAT:
    317   1.75    atatat 		mblowat = newval;
    318  1.122        ad 		pool_cache_setlowat(mb_cache, mblowat);
    319   1.75    atatat 		break;
    320   1.75    atatat 	case MBUF_MCLLOWAT:
    321   1.76    atatat 		mcllowat = newval;
    322  1.122        ad 		pool_cache_setlowat(mcl_cache, mcllowat);
    323   1.75    atatat 		break;
    324   1.75    atatat 	}
    325   1.75    atatat 
    326  1.199      maxv 	return 0;
    327   1.75    atatat }
    328   1.75    atatat 
    329   1.64      matt #ifdef MBUFTRACE
    330  1.124      yamt static void
    331  1.124      yamt mowner_conver_to_user_cb(void *v1, void *v2, struct cpu_info *ci)
    332  1.124      yamt {
    333  1.124      yamt 	struct mowner_counter *mc = v1;
    334  1.124      yamt 	struct mowner_user *mo_user = v2;
    335  1.124      yamt 	int i;
    336  1.124      yamt 
    337  1.124      yamt 	for (i = 0; i < MOWNER_COUNTER_NCOUNTERS; i++) {
    338  1.124      yamt 		mo_user->mo_counter[i] += mc->mc_counter[i];
    339  1.124      yamt 	}
    340  1.124      yamt }
    341  1.124      yamt 
    342  1.124      yamt static void
    343  1.124      yamt mowner_convert_to_user(struct mowner *mo, struct mowner_user *mo_user)
    344  1.124      yamt {
    345  1.124      yamt 
    346  1.124      yamt 	memset(mo_user, 0, sizeof(*mo_user));
    347  1.128      matt 	CTASSERT(sizeof(mo_user->mo_name) == sizeof(mo->mo_name));
    348  1.128      matt 	CTASSERT(sizeof(mo_user->mo_descr) == sizeof(mo->mo_descr));
    349  1.124      yamt 	memcpy(mo_user->mo_name, mo->mo_name, sizeof(mo->mo_name));
    350  1.124      yamt 	memcpy(mo_user->mo_descr, mo->mo_descr, sizeof(mo->mo_descr));
    351  1.124      yamt 	percpu_foreach(mo->mo_counters, mowner_conver_to_user_cb, mo_user);
    352  1.124      yamt }
    353  1.124      yamt 
    354   1.75    atatat static int
    355   1.75    atatat sysctl_kern_mbuf_mowners(SYSCTLFN_ARGS)
    356   1.75    atatat {
    357   1.75    atatat 	struct mowner *mo;
    358   1.75    atatat 	size_t len = 0;
    359   1.75    atatat 	int error = 0;
    360   1.75    atatat 
    361   1.75    atatat 	if (namelen != 0)
    362  1.199      maxv 		return EINVAL;
    363   1.75    atatat 	if (newp != NULL)
    364  1.199      maxv 		return EPERM;
    365   1.75    atatat 
    366   1.75    atatat 	LIST_FOREACH(mo, &mowners, mo_link) {
    367  1.124      yamt 		struct mowner_user mo_user;
    368  1.124      yamt 
    369  1.124      yamt 		mowner_convert_to_user(mo, &mo_user);
    370  1.124      yamt 
    371   1.75    atatat 		if (oldp != NULL) {
    372  1.124      yamt 			if (*oldlenp - len < sizeof(mo_user)) {
    373   1.75    atatat 				error = ENOMEM;
    374   1.75    atatat 				break;
    375   1.75    atatat 			}
    376  1.124      yamt 			error = copyout(&mo_user, (char *)oldp + len,
    377  1.124      yamt 			    sizeof(mo_user));
    378   1.75    atatat 			if (error)
    379   1.75    atatat 				break;
    380   1.64      matt 		}
    381  1.124      yamt 		len += sizeof(mo_user);
    382   1.75    atatat 	}
    383   1.75    atatat 
    384   1.75    atatat 	if (error == 0)
    385   1.64      matt 		*oldlenp = len;
    386   1.75    atatat 
    387  1.199      maxv 	return error;
    388   1.75    atatat }
    389   1.75    atatat #endif /* MBUFTRACE */
    390   1.75    atatat 
    391  1.124      yamt static void
    392  1.124      yamt mbstat_conver_to_user_cb(void *v1, void *v2, struct cpu_info *ci)
    393  1.124      yamt {
    394  1.124      yamt 	struct mbstat_cpu *mbsc = v1;
    395  1.124      yamt 	struct mbstat *mbs = v2;
    396  1.124      yamt 	int i;
    397  1.124      yamt 
    398  1.124      yamt 	for (i = 0; i < __arraycount(mbs->m_mtypes); i++) {
    399  1.124      yamt 		mbs->m_mtypes[i] += mbsc->m_mtypes[i];
    400  1.124      yamt 	}
    401  1.124      yamt }
    402  1.124      yamt 
    403  1.124      yamt static void
    404  1.124      yamt mbstat_convert_to_user(struct mbstat *mbs)
    405  1.124      yamt {
    406  1.124      yamt 
    407  1.124      yamt 	memset(mbs, 0, sizeof(*mbs));
    408  1.124      yamt 	mbs->m_drain = mbstat.m_drain;
    409  1.124      yamt 	percpu_foreach(mbstat_percpu, mbstat_conver_to_user_cb, mbs);
    410  1.124      yamt }
    411  1.124      yamt 
    412  1.124      yamt static int
    413  1.124      yamt sysctl_kern_mbuf_stats(SYSCTLFN_ARGS)
    414  1.124      yamt {
    415  1.124      yamt 	struct sysctlnode node;
    416  1.124      yamt 	struct mbstat mbs;
    417  1.124      yamt 
    418  1.124      yamt 	mbstat_convert_to_user(&mbs);
    419  1.124      yamt 	node = *rnode;
    420  1.124      yamt 	node.sysctl_data = &mbs;
    421  1.124      yamt 	node.sysctl_size = sizeof(mbs);
    422  1.124      yamt 	return sysctl_lookup(SYSCTLFN_CALL(&node));
    423  1.124      yamt }
    424  1.124      yamt 
    425  1.129     pooka static void
    426  1.131    cegger sysctl_kern_mbuf_setup(void)
    427   1.75    atatat {
    428   1.75    atatat 
    429  1.129     pooka 	KASSERT(mbuf_sysctllog == NULL);
    430  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    431   1.80    atatat 		       CTLFLAG_PERMANENT,
    432   1.82    atatat 		       CTLTYPE_NODE, "mbuf",
    433   1.82    atatat 		       SYSCTL_DESCR("mbuf control variables"),
    434   1.75    atatat 		       NULL, 0, NULL, 0,
    435   1.75    atatat 		       CTL_KERN, KERN_MBUF, CTL_EOL);
    436   1.75    atatat 
    437  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    438   1.80    atatat 		       CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
    439   1.82    atatat 		       CTLTYPE_INT, "msize",
    440   1.82    atatat 		       SYSCTL_DESCR("mbuf base size"),
    441   1.75    atatat 		       NULL, msize, NULL, 0,
    442   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_MSIZE, CTL_EOL);
    443  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    444   1.80    atatat 		       CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
    445   1.82    atatat 		       CTLTYPE_INT, "mclbytes",
    446   1.82    atatat 		       SYSCTL_DESCR("mbuf cluster size"),
    447   1.75    atatat 		       NULL, mclbytes, NULL, 0,
    448   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_MCLBYTES, CTL_EOL);
    449  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    450   1.80    atatat 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    451   1.82    atatat 		       CTLTYPE_INT, "nmbclusters",
    452   1.82    atatat 		       SYSCTL_DESCR("Limit on the number of mbuf clusters"),
    453   1.75    atatat 		       sysctl_kern_mbuf, 0, &nmbclusters, 0,
    454   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_NMBCLUSTERS, CTL_EOL);
    455  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    456   1.80    atatat 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    457   1.82    atatat 		       CTLTYPE_INT, "mblowat",
    458   1.82    atatat 		       SYSCTL_DESCR("mbuf low water mark"),
    459   1.75    atatat 		       sysctl_kern_mbuf, 0, &mblowat, 0,
    460   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_MBLOWAT, CTL_EOL);
    461  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    462   1.80    atatat 		       CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
    463   1.82    atatat 		       CTLTYPE_INT, "mcllowat",
    464   1.82    atatat 		       SYSCTL_DESCR("mbuf cluster low water mark"),
    465   1.75    atatat 		       sysctl_kern_mbuf, 0, &mcllowat, 0,
    466   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_MCLLOWAT, CTL_EOL);
    467  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    468   1.80    atatat 		       CTLFLAG_PERMANENT,
    469   1.82    atatat 		       CTLTYPE_STRUCT, "stats",
    470   1.82    atatat 		       SYSCTL_DESCR("mbuf allocation statistics"),
    471  1.124      yamt 		       sysctl_kern_mbuf_stats, 0, NULL, 0,
    472   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_STATS, CTL_EOL);
    473   1.75    atatat #ifdef MBUFTRACE
    474  1.129     pooka 	sysctl_createv(&mbuf_sysctllog, 0, NULL, NULL,
    475   1.80    atatat 		       CTLFLAG_PERMANENT,
    476   1.82    atatat 		       CTLTYPE_STRUCT, "mowners",
    477   1.82    atatat 		       SYSCTL_DESCR("Information about mbuf owners"),
    478   1.75    atatat 		       sysctl_kern_mbuf_mowners, 0, NULL, 0,
    479   1.75    atatat 		       CTL_KERN, KERN_MBUF, MBUF_MOWNERS, CTL_EOL);
    480  1.199      maxv #endif
    481   1.28   thorpej }
    482   1.28   thorpej 
    483   1.65   thorpej static int
    484  1.116      yamt mb_ctor(void *arg, void *object, int flags)
    485   1.65   thorpej {
    486   1.65   thorpej 	struct mbuf *m = object;
    487   1.65   thorpej 
    488   1.65   thorpej #ifdef POOL_VTOPHYS
    489   1.65   thorpej 	m->m_paddr = POOL_VTOPHYS(m);
    490   1.65   thorpej #else
    491   1.65   thorpej 	m->m_paddr = M_PADDR_INVALID;
    492   1.65   thorpej #endif
    493  1.199      maxv 	return 0;
    494    1.1       cgd }
    495    1.1       cgd 
    496  1.182      maxv void
    497  1.182      maxv m_pkthdr_remove(struct mbuf *m)
    498  1.182      maxv {
    499  1.182      maxv 	KASSERT(m->m_flags & M_PKTHDR);
    500  1.182      maxv 
    501  1.190      maxv 	if (M_READONLY(m)) {
    502  1.190      maxv 		/* Nothing we can do. */
    503  1.190      maxv 		return;
    504  1.190      maxv 	}
    505  1.190      maxv 
    506  1.182      maxv 	m_tag_delete_chain(m, NULL);
    507  1.182      maxv 	m->m_flags &= ~M_PKTHDR;
    508  1.182      maxv 	memset(&m->m_pkthdr, 0, sizeof(m->m_pkthdr));
    509  1.182      maxv }
    510  1.182      maxv 
    511  1.150  christos /*
    512  1.150  christos  * Add mbuf to the end of a chain
    513  1.150  christos  */
    514  1.150  christos struct mbuf *
    515  1.179      maxv m_add(struct mbuf *c, struct mbuf *m)
    516  1.179      maxv {
    517  1.150  christos 	struct mbuf *n;
    518  1.150  christos 
    519  1.150  christos 	if (c == NULL)
    520  1.150  christos 		return m;
    521  1.150  christos 
    522  1.150  christos 	for (n = c; n->m_next != NULL; n = n->m_next)
    523  1.150  christos 		continue;
    524  1.150  christos 	n->m_next = m;
    525  1.150  christos 	return c;
    526  1.150  christos }
    527  1.150  christos 
    528    1.1       cgd struct mbuf *
    529   1.62   thorpej m_get(int nowait, int type)
    530    1.1       cgd {
    531   1.27      matt 	struct mbuf *m;
    532    1.1       cgd 
    533  1.142    dyoung 	KASSERT(type != MT_FREE);
    534  1.142    dyoung 
    535  1.124      yamt 	m = pool_cache_get(mb_cache,
    536  1.173  christos 	    nowait == M_WAIT ? PR_WAITOK|PR_LIMITFAIL : PR_NOWAIT);
    537  1.124      yamt 	if (m == NULL)
    538  1.124      yamt 		return NULL;
    539  1.124      yamt 
    540  1.124      yamt 	mbstat_type_add(type, 1);
    541  1.164  knakahar 
    542  1.184      maxv 	mowner_init(m, type);
    543  1.184      maxv 	m->m_ext_ref = m; /* default */
    544  1.184      maxv 	m->m_type = type;
    545  1.184      maxv 	m->m_len = 0;
    546  1.184      maxv 	m->m_next = NULL;
    547  1.184      maxv 	m->m_nextpkt = NULL; /* default */
    548  1.184      maxv 	m->m_data = m->m_dat;
    549  1.184      maxv 	m->m_flags = 0; /* default */
    550  1.124      yamt 
    551  1.124      yamt 	return m;
    552    1.1       cgd }
    553    1.1       cgd 
    554    1.1       cgd struct mbuf *
    555   1.62   thorpej m_gethdr(int nowait, int type)
    556    1.1       cgd {
    557   1.27      matt 	struct mbuf *m;
    558    1.1       cgd 
    559  1.124      yamt 	m = m_get(nowait, type);
    560  1.124      yamt 	if (m == NULL)
    561  1.124      yamt 		return NULL;
    562  1.124      yamt 
    563  1.184      maxv 	m->m_data = m->m_pktdat;
    564  1.184      maxv 	m->m_flags = M_PKTHDR;
    565  1.184      maxv 
    566  1.184      maxv 	m_reset_rcvif(m);
    567  1.184      maxv 	m->m_pkthdr.len = 0;
    568  1.184      maxv 	m->m_pkthdr.csum_flags = 0;
    569  1.184      maxv 	m->m_pkthdr.csum_data = 0;
    570  1.184      maxv 	SLIST_INIT(&m->m_pkthdr.tags);
    571  1.184      maxv 
    572  1.184      maxv 	m->m_pkthdr.pattr_class = NULL;
    573  1.184      maxv 	m->m_pkthdr.pattr_af = AF_UNSPEC;
    574  1.184      maxv 	m->m_pkthdr.pattr_hdr = NULL;
    575  1.124      yamt 
    576  1.124      yamt 	return m;
    577    1.1       cgd }
    578    1.1       cgd 
    579   1.64      matt void
    580   1.64      matt m_clget(struct mbuf *m, int nowait)
    581   1.64      matt {
    582   1.71    simonb 
    583  1.197      maxv 	_MCLGET(m, mcl_cache, MCLBYTES, nowait);
    584   1.64      matt }
    585   1.64      matt 
    586   1.64      matt #ifdef MBUFTRACE
    587   1.83  jonathan /*
    588   1.83  jonathan  * Walk a chain of mbufs, claiming ownership of each mbuf in the chain.
    589   1.83  jonathan  */
    590   1.64      matt void
    591   1.83  jonathan m_claimm(struct mbuf *m, struct mowner *mo)
    592   1.64      matt {
    593   1.71    simonb 
    594   1.64      matt 	for (; m != NULL; m = m->m_next)
    595   1.64      matt 		MCLAIM(m, mo);
    596   1.64      matt }
    597   1.64      matt #endif
    598   1.64      matt 
    599    1.1       cgd /*
    600  1.194      maxv  * Utility function for M_PREPEND. Do *NOT* use it directly.
    601    1.1       cgd  */
    602    1.1       cgd struct mbuf *
    603   1.62   thorpej m_prepend(struct mbuf *m, int len, int how)
    604    1.1       cgd {
    605    1.1       cgd 	struct mbuf *mn;
    606    1.1       cgd 
    607  1.180      maxv 	if (__predict_false(len > MHLEN)) {
    608  1.180      maxv 		panic("%s: len > MHLEN", __func__);
    609  1.180      maxv 	}
    610  1.180      maxv 
    611  1.156  christos 	KASSERT(len != M_COPYALL);
    612  1.153  christos 	mn = m_get(how, m->m_type);
    613  1.143    plunky 	if (mn == NULL) {
    614    1.1       cgd 		m_freem(m);
    615  1.179      maxv 		return NULL;
    616    1.1       cgd 	}
    617  1.178      maxv 
    618    1.1       cgd 	if (m->m_flags & M_PKTHDR) {
    619  1.101      yamt 		M_MOVE_PKTHDR(mn, m);
    620   1.64      matt 	} else {
    621   1.64      matt 		MCLAIM(mn, m->m_owner);
    622    1.1       cgd 	}
    623    1.1       cgd 	mn->m_next = m;
    624    1.1       cgd 	m = mn;
    625  1.178      maxv 
    626  1.178      maxv 	if (m->m_flags & M_PKTHDR) {
    627  1.178      maxv 		if (len < MHLEN)
    628  1.178      maxv 			MH_ALIGN(m, len);
    629  1.178      maxv 	} else {
    630  1.178      maxv 		if (len < MLEN)
    631  1.178      maxv 			M_ALIGN(m, len);
    632  1.178      maxv 	}
    633  1.178      maxv 
    634    1.1       cgd 	m->m_len = len;
    635  1.179      maxv 	return m;
    636    1.1       cgd }
    637    1.1       cgd 
    638    1.1       cgd struct mbuf *
    639  1.195      maxv m_copym(struct mbuf *m, int off, int len, int wait)
    640    1.1       cgd {
    641  1.195      maxv 	/* Shallow copy on M_EXT. */
    642  1.195      maxv 	return m_copy_internal(m, off, len, wait, false);
    643   1.44    itojun }
    644   1.44    itojun 
    645   1.44    itojun struct mbuf *
    646  1.195      maxv m_dup(struct mbuf *m, int off, int len, int wait)
    647   1.44    itojun {
    648  1.195      maxv 	/* Deep copy. */
    649  1.195      maxv 	return m_copy_internal(m, off, len, wait, true);
    650   1.44    itojun }
    651   1.44    itojun 
    652  1.154  christos static inline int
    653  1.179      maxv m_copylen(int len, int copylen)
    654  1.179      maxv {
    655  1.179      maxv 	return (len == M_COPYALL) ? copylen : min(len, copylen);
    656  1.154  christos }
    657  1.154  christos 
    658   1.44    itojun static struct mbuf *
    659  1.195      maxv m_copy_internal(struct mbuf *m, int off0, int len, int wait, bool deep)
    660   1.44    itojun {
    661   1.27      matt 	struct mbuf *n, **np;
    662   1.27      matt 	int off = off0;
    663    1.1       cgd 	struct mbuf *top;
    664    1.1       cgd 	int copyhdr = 0;
    665    1.1       cgd 
    666  1.154  christos 	if (off < 0 || (len != M_COPYALL && len < 0))
    667  1.196      maxv 		panic("%s: off %d, len %d", __func__, off, len);
    668    1.1       cgd 	if (off == 0 && m->m_flags & M_PKTHDR)
    669    1.1       cgd 		copyhdr = 1;
    670    1.1       cgd 	while (off > 0) {
    671  1.179      maxv 		if (m == NULL)
    672  1.199      maxv 			panic("%s: m == NULL, off %d", __func__, off);
    673    1.1       cgd 		if (off < m->m_len)
    674    1.1       cgd 			break;
    675    1.1       cgd 		off -= m->m_len;
    676    1.1       cgd 		m = m->m_next;
    677    1.1       cgd 	}
    678  1.179      maxv 
    679    1.1       cgd 	np = &top;
    680  1.179      maxv 	top = NULL;
    681  1.155     skrll 	while (len == M_COPYALL || len > 0) {
    682  1.179      maxv 		if (m == NULL) {
    683    1.1       cgd 			if (len != M_COPYALL)
    684  1.196      maxv 				panic("%s: m == NULL, len %d [!COPYALL]",
    685  1.196      maxv 				    __func__, len);
    686    1.1       cgd 			break;
    687    1.1       cgd 		}
    688  1.179      maxv 
    689  1.153  christos 		n = m_get(wait, m->m_type);
    690    1.1       cgd 		*np = n;
    691  1.179      maxv 		if (n == NULL)
    692    1.1       cgd 			goto nospace;
    693   1.64      matt 		MCLAIM(n, m->m_owner);
    694  1.179      maxv 
    695    1.1       cgd 		if (copyhdr) {
    696    1.1       cgd 			M_COPY_PKTHDR(n, m);
    697    1.1       cgd 			if (len == M_COPYALL)
    698    1.1       cgd 				n->m_pkthdr.len -= off0;
    699    1.1       cgd 			else
    700    1.1       cgd 				n->m_pkthdr.len = len;
    701    1.1       cgd 			copyhdr = 0;
    702    1.1       cgd 		}
    703  1.154  christos 		n->m_len = m_copylen(len, m->m_len - off);
    704  1.179      maxv 
    705    1.1       cgd 		if (m->m_flags & M_EXT) {
    706   1.44    itojun 			if (!deep) {
    707   1.44    itojun 				n->m_data = m->m_data + off;
    708   1.44    itojun 				MCLADDREFERENCE(m, n);
    709   1.44    itojun 			} else {
    710   1.48    itojun 				/*
    711  1.181      maxv 				 * We don't care if MCLGET fails. n->m_len is
    712  1.181      maxv 				 * recomputed and handles that.
    713   1.48    itojun 				 */
    714   1.44    itojun 				MCLGET(n, wait);
    715  1.161   mlelstv 				n->m_len = 0;
    716   1.50    itojun 				n->m_len = M_TRAILINGSPACE(n);
    717  1.154  christos 				n->m_len = m_copylen(len, n->m_len);
    718   1.50    itojun 				n->m_len = min(n->m_len, m->m_len - off);
    719  1.119  christos 				memcpy(mtod(n, void *), mtod(m, char *) + off,
    720   1.44    itojun 				    (unsigned)n->m_len);
    721   1.44    itojun 			}
    722  1.179      maxv 		} else {
    723  1.119  christos 			memcpy(mtod(n, void *), mtod(m, char *) + off,
    724    1.1       cgd 			    (unsigned)n->m_len);
    725  1.179      maxv 		}
    726  1.179      maxv 
    727    1.1       cgd 		if (len != M_COPYALL)
    728    1.1       cgd 			len -= n->m_len;
    729   1.50    itojun 		off += n->m_len;
    730  1.199      maxv 
    731  1.199      maxv 		KASSERT(off <= m->m_len);
    732  1.199      maxv 
    733   1.50    itojun 		if (off == m->m_len) {
    734   1.50    itojun 			m = m->m_next;
    735   1.50    itojun 			off = 0;
    736   1.50    itojun 		}
    737    1.1       cgd 		np = &n->m_next;
    738    1.1       cgd 	}
    739  1.179      maxv 
    740  1.179      maxv 	return top;
    741  1.179      maxv 
    742    1.1       cgd nospace:
    743    1.1       cgd 	m_freem(top);
    744  1.179      maxv 	return NULL;
    745    1.1       cgd }
    746    1.1       cgd 
    747    1.1       cgd /*
    748   1.18   thorpej  * Copy an entire packet, including header (which must be present).
    749  1.181      maxv  * An optimization of the common case 'm_copym(m, 0, M_COPYALL, how)'.
    750   1.18   thorpej  */
    751   1.18   thorpej struct mbuf *
    752   1.62   thorpej m_copypacket(struct mbuf *m, int how)
    753   1.18   thorpej {
    754   1.18   thorpej 	struct mbuf *top, *n, *o;
    755   1.18   thorpej 
    756  1.198      maxv 	if (__predict_false((m->m_flags & M_PKTHDR) == 0)) {
    757  1.198      maxv 		panic("%s: no header (m = %p)", __func__, m);
    758  1.198      maxv 	}
    759  1.198      maxv 
    760  1.153  christos 	n = m_get(how, m->m_type);
    761   1.18   thorpej 	top = n;
    762   1.18   thorpej 	if (!n)
    763   1.18   thorpej 		goto nospace;
    764   1.18   thorpej 
    765   1.64      matt 	MCLAIM(n, m->m_owner);
    766   1.18   thorpej 	M_COPY_PKTHDR(n, m);
    767   1.18   thorpej 	n->m_len = m->m_len;
    768   1.18   thorpej 	if (m->m_flags & M_EXT) {
    769   1.18   thorpej 		n->m_data = m->m_data;
    770   1.18   thorpej 		MCLADDREFERENCE(m, n);
    771   1.18   thorpej 	} else {
    772   1.30     perry 		memcpy(mtod(n, char *), mtod(m, char *), n->m_len);
    773   1.18   thorpej 	}
    774   1.18   thorpej 
    775   1.18   thorpej 	m = m->m_next;
    776   1.18   thorpej 	while (m) {
    777  1.153  christos 		o = m_get(how, m->m_type);
    778   1.18   thorpej 		if (!o)
    779   1.18   thorpej 			goto nospace;
    780   1.18   thorpej 
    781   1.64      matt 		MCLAIM(o, m->m_owner);
    782   1.18   thorpej 		n->m_next = o;
    783   1.18   thorpej 		n = n->m_next;
    784   1.18   thorpej 
    785   1.18   thorpej 		n->m_len = m->m_len;
    786   1.18   thorpej 		if (m->m_flags & M_EXT) {
    787   1.18   thorpej 			n->m_data = m->m_data;
    788   1.18   thorpej 			MCLADDREFERENCE(m, n);
    789   1.18   thorpej 		} else {
    790   1.30     perry 			memcpy(mtod(n, char *), mtod(m, char *), n->m_len);
    791   1.18   thorpej 		}
    792   1.18   thorpej 
    793   1.18   thorpej 		m = m->m_next;
    794   1.18   thorpej 	}
    795   1.18   thorpej 	return top;
    796  1.181      maxv 
    797   1.18   thorpej nospace:
    798   1.18   thorpej 	m_freem(top);
    799   1.71    simonb 	return NULL;
    800   1.18   thorpej }
    801   1.18   thorpej 
    802   1.14  christos void
    803  1.200      maxv m_copydata(struct mbuf *m, int off, int len, void *cp)
    804    1.1       cgd {
    805  1.200      maxv 	unsigned int count;
    806  1.179      maxv 	struct mbuf *m0 = m;
    807  1.179      maxv 	int len0 = len;
    808  1.179      maxv 	int off0 = off;
    809  1.200      maxv 	void *cp0 = cp;
    810    1.1       cgd 
    811  1.156  christos 	KASSERT(len != M_COPYALL);
    812    1.1       cgd 	if (off < 0 || len < 0)
    813   1.90      matt 		panic("m_copydata: off %d, len %d", off, len);
    814    1.1       cgd 	while (off > 0) {
    815   1.94      tron 		if (m == NULL)
    816  1.151      matt 			panic("m_copydata(%p,%d,%d,%p): m=NULL, off=%d (%d)",
    817  1.200      maxv 			    m0, len0, off0, cp0, off, off0 - off);
    818    1.1       cgd 		if (off < m->m_len)
    819    1.1       cgd 			break;
    820    1.1       cgd 		off -= m->m_len;
    821    1.1       cgd 		m = m->m_next;
    822    1.1       cgd 	}
    823    1.1       cgd 	while (len > 0) {
    824   1.94      tron 		if (m == NULL)
    825  1.151      matt 			panic("m_copydata(%p,%d,%d,%p): "
    826  1.151      matt 			    "m=NULL, off=%d (%d), len=%d (%d)",
    827  1.200      maxv 			    m0, len0, off0, cp0,
    828  1.151      matt 			    off, off0 - off, len, len0 - len);
    829    1.9   mycroft 		count = min(m->m_len - off, len);
    830  1.119  christos 		memcpy(cp, mtod(m, char *) + off, count);
    831    1.1       cgd 		len -= count;
    832  1.119  christos 		cp = (char *)cp + count;
    833    1.1       cgd 		off = 0;
    834    1.1       cgd 		m = m->m_next;
    835    1.1       cgd 	}
    836    1.1       cgd }
    837    1.1       cgd 
    838    1.1       cgd /*
    839    1.1       cgd  * Concatenate mbuf chain n to m.
    840   1.72    itojun  * n might be copied into m (when n->m_len is small), therefore data portion of
    841   1.72    itojun  * n could be copied into an mbuf of different mbuf type.
    842    1.1       cgd  * Any m_pkthdr is not updated.
    843    1.1       cgd  */
    844   1.14  christos void
    845   1.62   thorpej m_cat(struct mbuf *m, struct mbuf *n)
    846    1.1       cgd {
    847   1.73      yamt 
    848    1.1       cgd 	while (m->m_next)
    849    1.1       cgd 		m = m->m_next;
    850    1.1       cgd 	while (n) {
    851   1.77    itojun 		if (M_READONLY(m) || n->m_len > M_TRAILINGSPACE(m)) {
    852    1.1       cgd 			/* just join the two chains */
    853    1.1       cgd 			m->m_next = n;
    854    1.1       cgd 			return;
    855    1.1       cgd 		}
    856    1.1       cgd 		/* splat the data from one into the other */
    857  1.119  christos 		memcpy(mtod(m, char *) + m->m_len, mtod(n, void *),
    858    1.1       cgd 		    (u_int)n->m_len);
    859    1.1       cgd 		m->m_len += n->m_len;
    860    1.1       cgd 		n = m_free(n);
    861    1.1       cgd 	}
    862    1.1       cgd }
    863    1.1       cgd 
    864   1.11   mycroft void
    865   1.62   thorpej m_adj(struct mbuf *mp, int req_len)
    866    1.1       cgd {
    867   1.27      matt 	int len = req_len;
    868   1.27      matt 	struct mbuf *m;
    869   1.27      matt 	int count;
    870    1.1       cgd 
    871    1.1       cgd 	if ((m = mp) == NULL)
    872    1.1       cgd 		return;
    873    1.1       cgd 	if (len >= 0) {
    874    1.1       cgd 		/*
    875    1.1       cgd 		 * Trim from head.
    876    1.1       cgd 		 */
    877    1.1       cgd 		while (m != NULL && len > 0) {
    878    1.1       cgd 			if (m->m_len <= len) {
    879    1.1       cgd 				len -= m->m_len;
    880    1.1       cgd 				m->m_len = 0;
    881    1.1       cgd 				m = m->m_next;
    882    1.1       cgd 			} else {
    883    1.1       cgd 				m->m_len -= len;
    884    1.1       cgd 				m->m_data += len;
    885    1.1       cgd 				len = 0;
    886    1.1       cgd 			}
    887    1.1       cgd 		}
    888    1.1       cgd 		if (mp->m_flags & M_PKTHDR)
    889  1.181      maxv 			mp->m_pkthdr.len -= (req_len - len);
    890    1.1       cgd 	} else {
    891    1.1       cgd 		/*
    892    1.1       cgd 		 * Trim from tail.  Scan the mbuf chain,
    893    1.1       cgd 		 * calculating its length and finding the last mbuf.
    894    1.1       cgd 		 * If the adjustment only affects this mbuf, then just
    895    1.1       cgd 		 * adjust and return.  Otherwise, rescan and truncate
    896    1.1       cgd 		 * after the remaining size.
    897    1.1       cgd 		 */
    898    1.1       cgd 		len = -len;
    899    1.1       cgd 		count = 0;
    900    1.1       cgd 		for (;;) {
    901    1.1       cgd 			count += m->m_len;
    902  1.181      maxv 			if (m->m_next == NULL)
    903    1.1       cgd 				break;
    904    1.1       cgd 			m = m->m_next;
    905    1.1       cgd 		}
    906    1.1       cgd 		if (m->m_len >= len) {
    907    1.1       cgd 			m->m_len -= len;
    908    1.8   deraadt 			if (mp->m_flags & M_PKTHDR)
    909    1.8   deraadt 				mp->m_pkthdr.len -= len;
    910    1.1       cgd 			return;
    911    1.1       cgd 		}
    912  1.181      maxv 
    913    1.1       cgd 		count -= len;
    914    1.1       cgd 		if (count < 0)
    915    1.1       cgd 			count = 0;
    916  1.181      maxv 
    917    1.1       cgd 		/*
    918    1.1       cgd 		 * Correct length for chain is "count".
    919    1.1       cgd 		 * Find the mbuf with last data, adjust its length,
    920    1.1       cgd 		 * and toss data from remaining mbufs on chain.
    921    1.1       cgd 		 */
    922    1.1       cgd 		m = mp;
    923    1.1       cgd 		if (m->m_flags & M_PKTHDR)
    924    1.1       cgd 			m->m_pkthdr.len = count;
    925    1.1       cgd 		for (; m; m = m->m_next) {
    926    1.1       cgd 			if (m->m_len >= count) {
    927    1.1       cgd 				m->m_len = count;
    928    1.1       cgd 				break;
    929    1.1       cgd 			}
    930    1.1       cgd 			count -= m->m_len;
    931    1.1       cgd 		}
    932  1.181      maxv 		if (m) {
    933  1.110  christos 			while (m->m_next)
    934  1.110  christos 				(m = m->m_next)->m_len = 0;
    935  1.181      maxv 		}
    936    1.1       cgd 	}
    937    1.1       cgd }
    938    1.1       cgd 
    939    1.1       cgd /*
    940  1.148     rmind  * m_ensure_contig: rearrange an mbuf chain that given length of bytes
    941  1.148     rmind  * would be contiguous and in the data area of an mbuf (therefore, mtod()
    942  1.148     rmind  * would work for a structure of given length).
    943  1.148     rmind  *
    944  1.148     rmind  * => On success, returns true and the resulting mbuf chain; false otherwise.
    945  1.148     rmind  * => The mbuf chain may change, but is always preserved valid.
    946    1.1       cgd  */
    947  1.148     rmind bool
    948  1.148     rmind m_ensure_contig(struct mbuf **m0, int len)
    949    1.1       cgd {
    950  1.148     rmind 	struct mbuf *n = *m0, *m;
    951  1.148     rmind 	size_t count, space;
    952    1.1       cgd 
    953  1.156  christos 	KASSERT(len != M_COPYALL);
    954    1.1       cgd 	/*
    955    1.1       cgd 	 * If first mbuf has no cluster, and has room for len bytes
    956    1.1       cgd 	 * without shifting current data, pullup into it,
    957    1.1       cgd 	 * otherwise allocate a new mbuf to prepend to the chain.
    958    1.1       cgd 	 */
    959    1.1       cgd 	if ((n->m_flags & M_EXT) == 0 &&
    960    1.1       cgd 	    n->m_data + len < &n->m_dat[MLEN] && n->m_next) {
    961  1.148     rmind 		if (n->m_len >= len) {
    962  1.148     rmind 			return true;
    963  1.148     rmind 		}
    964    1.1       cgd 		m = n;
    965    1.1       cgd 		n = n->m_next;
    966    1.1       cgd 		len -= m->m_len;
    967    1.1       cgd 	} else {
    968  1.148     rmind 		if (len > MHLEN) {
    969  1.148     rmind 			return false;
    970  1.148     rmind 		}
    971  1.153  christos 		m = m_get(M_DONTWAIT, n->m_type);
    972  1.148     rmind 		if (m == NULL) {
    973  1.148     rmind 			return false;
    974  1.148     rmind 		}
    975   1.64      matt 		MCLAIM(m, n->m_owner);
    976    1.1       cgd 		if (n->m_flags & M_PKTHDR) {
    977  1.101      yamt 			M_MOVE_PKTHDR(m, n);
    978    1.1       cgd 		}
    979    1.1       cgd 	}
    980    1.1       cgd 	space = &m->m_dat[MLEN] - (m->m_data + m->m_len);
    981    1.1       cgd 	do {
    982  1.148     rmind 		count = MIN(MIN(MAX(len, max_protohdr), space), n->m_len);
    983  1.119  christos 		memcpy(mtod(m, char *) + m->m_len, mtod(n, void *),
    984    1.1       cgd 		  (unsigned)count);
    985    1.1       cgd 		len -= count;
    986    1.1       cgd 		m->m_len += count;
    987    1.1       cgd 		n->m_len -= count;
    988    1.1       cgd 		space -= count;
    989    1.1       cgd 		if (n->m_len)
    990    1.1       cgd 			n->m_data += count;
    991    1.1       cgd 		else
    992    1.1       cgd 			n = m_free(n);
    993    1.1       cgd 	} while (len > 0 && n);
    994  1.148     rmind 
    995  1.148     rmind 	m->m_next = n;
    996  1.148     rmind 	*m0 = m;
    997  1.148     rmind 
    998  1.148     rmind 	return len <= 0;
    999  1.148     rmind }
   1000  1.148     rmind 
   1001  1.148     rmind /*
   1002  1.148     rmind  * m_pullup: same as m_ensure_contig(), but destroys mbuf chain on error.
   1003  1.148     rmind  */
   1004  1.148     rmind struct mbuf *
   1005  1.148     rmind m_pullup(struct mbuf *n, int len)
   1006  1.148     rmind {
   1007  1.148     rmind 	struct mbuf *m = n;
   1008  1.148     rmind 
   1009  1.156  christos 	KASSERT(len != M_COPYALL);
   1010  1.148     rmind 	if (!m_ensure_contig(&m, len)) {
   1011  1.148     rmind 		KASSERT(m != NULL);
   1012  1.148     rmind 		m_freem(m);
   1013  1.148     rmind 		m = NULL;
   1014    1.1       cgd 	}
   1015  1.148     rmind 	return m;
   1016   1.60   thorpej }
   1017   1.60   thorpej 
   1018   1.60   thorpej /*
   1019   1.60   thorpej  * Like m_pullup(), except a new mbuf is always allocated, and we allow
   1020   1.60   thorpej  * the amount of empty space before the data in the new mbuf to be specified
   1021   1.60   thorpej  * (in the event that the caller expects to prepend later).
   1022   1.60   thorpej  */
   1023   1.60   thorpej struct mbuf *
   1024   1.60   thorpej m_copyup(struct mbuf *n, int len, int dstoff)
   1025   1.60   thorpej {
   1026   1.60   thorpej 	struct mbuf *m;
   1027   1.60   thorpej 	int count, space;
   1028   1.60   thorpej 
   1029  1.156  christos 	KASSERT(len != M_COPYALL);
   1030  1.193      maxv 	if (len > ((int)MHLEN - dstoff))
   1031   1.60   thorpej 		goto bad;
   1032  1.153  christos 	m = m_get(M_DONTWAIT, n->m_type);
   1033   1.60   thorpej 	if (m == NULL)
   1034   1.60   thorpej 		goto bad;
   1035   1.64      matt 	MCLAIM(m, n->m_owner);
   1036   1.60   thorpej 	if (n->m_flags & M_PKTHDR) {
   1037  1.101      yamt 		M_MOVE_PKTHDR(m, n);
   1038   1.60   thorpej 	}
   1039   1.60   thorpej 	m->m_data += dstoff;
   1040   1.60   thorpej 	space = &m->m_dat[MLEN] - (m->m_data + m->m_len);
   1041   1.60   thorpej 	do {
   1042   1.60   thorpej 		count = min(min(max(len, max_protohdr), space), n->m_len);
   1043  1.119  christos 		memcpy(mtod(m, char *) + m->m_len, mtod(n, void *),
   1044   1.60   thorpej 		    (unsigned)count);
   1045   1.60   thorpej 		len -= count;
   1046   1.60   thorpej 		m->m_len += count;
   1047   1.60   thorpej 		n->m_len -= count;
   1048   1.60   thorpej 		space -= count;
   1049   1.60   thorpej 		if (n->m_len)
   1050   1.60   thorpej 			n->m_data += count;
   1051   1.60   thorpej 		else
   1052   1.60   thorpej 			n = m_free(n);
   1053   1.60   thorpej 	} while (len > 0 && n);
   1054   1.60   thorpej 	if (len > 0) {
   1055   1.60   thorpej 		(void) m_free(m);
   1056   1.60   thorpej 		goto bad;
   1057   1.60   thorpej 	}
   1058   1.60   thorpej 	m->m_next = n;
   1059  1.199      maxv 	return m;
   1060   1.60   thorpej  bad:
   1061   1.60   thorpej 	m_freem(n);
   1062  1.199      maxv 	return NULL;
   1063    1.9   mycroft }
   1064    1.9   mycroft 
   1065    1.9   mycroft struct mbuf *
   1066  1.195      maxv m_split(struct mbuf *m0, int len, int wait)
   1067    1.9   mycroft {
   1068  1.195      maxv 	return m_split_internal(m0, len, wait, true);
   1069   1.85      yamt }
   1070   1.85      yamt 
   1071   1.85      yamt static struct mbuf *
   1072  1.195      maxv m_split_internal(struct mbuf *m0, int len0, int wait, bool copyhdr)
   1073   1.85      yamt {
   1074   1.27      matt 	struct mbuf *m, *n;
   1075   1.22   thorpej 	unsigned len = len0, remain, len_save;
   1076    1.9   mycroft 
   1077  1.156  christos 	KASSERT(len0 != M_COPYALL);
   1078    1.9   mycroft 	for (m = m0; m && len > m->m_len; m = m->m_next)
   1079    1.9   mycroft 		len -= m->m_len;
   1080  1.181      maxv 	if (m == NULL)
   1081  1.181      maxv 		return NULL;
   1082  1.181      maxv 
   1083    1.9   mycroft 	remain = m->m_len - len;
   1084   1.85      yamt 	if (copyhdr && (m0->m_flags & M_PKTHDR)) {
   1085  1.153  christos 		n = m_gethdr(wait, m0->m_type);
   1086  1.153  christos 		if (n == NULL)
   1087  1.153  christos 			return NULL;
   1088  1.181      maxv 
   1089  1.112     pavel 		MCLAIM(n, m0->m_owner);
   1090  1.167     ozaki 		m_copy_rcvif(n, m0);
   1091    1.9   mycroft 		n->m_pkthdr.len = m0->m_pkthdr.len - len0;
   1092   1.22   thorpej 		len_save = m0->m_pkthdr.len;
   1093    1.9   mycroft 		m0->m_pkthdr.len = len0;
   1094  1.181      maxv 
   1095    1.9   mycroft 		if (m->m_flags & M_EXT)
   1096    1.9   mycroft 			goto extpacket;
   1097  1.181      maxv 
   1098    1.9   mycroft 		if (remain > MHLEN) {
   1099    1.9   mycroft 			/* m can't be the lead packet */
   1100    1.9   mycroft 			MH_ALIGN(n, 0);
   1101  1.132    bouyer 			n->m_len = 0;
   1102    1.9   mycroft 			n->m_next = m_split(m, len, wait);
   1103  1.181      maxv 			if (n->m_next == NULL) {
   1104  1.181      maxv 				(void)m_free(n);
   1105   1.22   thorpej 				m0->m_pkthdr.len = len_save;
   1106  1.181      maxv 				return NULL;
   1107  1.181      maxv 			}
   1108  1.181      maxv 			return n;
   1109  1.181      maxv 		} else {
   1110    1.9   mycroft 			MH_ALIGN(n, remain);
   1111  1.181      maxv 		}
   1112    1.9   mycroft 	} else if (remain == 0) {
   1113    1.9   mycroft 		n = m->m_next;
   1114  1.181      maxv 		m->m_next = NULL;
   1115  1.181      maxv 		return n;
   1116    1.9   mycroft 	} else {
   1117  1.153  christos 		n = m_get(wait, m->m_type);
   1118  1.181      maxv 		if (n == NULL)
   1119  1.181      maxv 			return NULL;
   1120   1.64      matt 		MCLAIM(n, m->m_owner);
   1121    1.9   mycroft 		M_ALIGN(n, remain);
   1122    1.9   mycroft 	}
   1123  1.181      maxv 
   1124    1.9   mycroft extpacket:
   1125    1.9   mycroft 	if (m->m_flags & M_EXT) {
   1126  1.125      yamt 		n->m_data = m->m_data + len;
   1127   1.18   thorpej 		MCLADDREFERENCE(m, n);
   1128    1.9   mycroft 	} else {
   1129  1.119  christos 		memcpy(mtod(n, void *), mtod(m, char *) + len, remain);
   1130    1.9   mycroft 	}
   1131  1.181      maxv 
   1132    1.9   mycroft 	n->m_len = remain;
   1133    1.9   mycroft 	m->m_len = len;
   1134    1.9   mycroft 	n->m_next = m->m_next;
   1135  1.181      maxv 	m->m_next = NULL;
   1136  1.181      maxv 	return n;
   1137    1.9   mycroft }
   1138  1.181      maxv 
   1139    1.9   mycroft /*
   1140    1.9   mycroft  * Routine to copy from device local memory into mbufs.
   1141    1.9   mycroft  */
   1142    1.9   mycroft struct mbuf *
   1143   1.62   thorpej m_devget(char *buf, int totlen, int off0, struct ifnet *ifp,
   1144   1.62   thorpej     void (*copy)(const void *from, void *to, size_t len))
   1145    1.9   mycroft {
   1146   1.27      matt 	struct mbuf *m;
   1147  1.181      maxv 	struct mbuf *top = NULL, **mp = &top;
   1148   1.27      matt 	int off = off0, len;
   1149  1.181      maxv 	char *cp, *epkt;
   1150    1.9   mycroft 
   1151    1.9   mycroft 	cp = buf;
   1152    1.9   mycroft 	epkt = cp + totlen;
   1153    1.9   mycroft 	if (off) {
   1154   1.13       cgd 		/*
   1155   1.13       cgd 		 * If 'off' is non-zero, packet is trailer-encapsulated,
   1156   1.13       cgd 		 * so we have to skip the type and length fields.
   1157   1.13       cgd 		 */
   1158  1.104     perry 		cp += off + 2 * sizeof(uint16_t);
   1159  1.104     perry 		totlen -= 2 * sizeof(uint16_t);
   1160    1.9   mycroft 	}
   1161  1.181      maxv 
   1162  1.153  christos 	m = m_gethdr(M_DONTWAIT, MT_DATA);
   1163  1.153  christos 	if (m == NULL)
   1164  1.153  christos 		return NULL;
   1165  1.166     ozaki 	m_set_rcvif(m, ifp);
   1166    1.9   mycroft 	m->m_pkthdr.len = totlen;
   1167    1.9   mycroft 	m->m_len = MHLEN;
   1168    1.9   mycroft 
   1169    1.9   mycroft 	while (totlen > 0) {
   1170    1.9   mycroft 		if (top) {
   1171  1.153  christos 			m = m_get(M_DONTWAIT, MT_DATA);
   1172  1.181      maxv 			if (m == NULL) {
   1173    1.9   mycroft 				m_freem(top);
   1174  1.181      maxv 				return NULL;
   1175    1.9   mycroft 			}
   1176    1.9   mycroft 			m->m_len = MLEN;
   1177    1.9   mycroft 		}
   1178  1.181      maxv 
   1179    1.9   mycroft 		len = min(totlen, epkt - cp);
   1180  1.181      maxv 
   1181    1.9   mycroft 		if (len >= MINCLSIZE) {
   1182    1.9   mycroft 			MCLGET(m, M_DONTWAIT);
   1183   1.19   mycroft 			if ((m->m_flags & M_EXT) == 0) {
   1184   1.20   mycroft 				m_free(m);
   1185   1.19   mycroft 				m_freem(top);
   1186  1.181      maxv 				return NULL;
   1187   1.19   mycroft 			}
   1188   1.19   mycroft 			m->m_len = len = min(len, MCLBYTES);
   1189    1.9   mycroft 		} else {
   1190    1.9   mycroft 			/*
   1191    1.9   mycroft 			 * Place initial small packet/header at end of mbuf.
   1192    1.9   mycroft 			 */
   1193    1.9   mycroft 			if (len < m->m_len) {
   1194    1.9   mycroft 				if (top == 0 && len + max_linkhdr <= m->m_len)
   1195    1.9   mycroft 					m->m_data += max_linkhdr;
   1196    1.9   mycroft 				m->m_len = len;
   1197    1.9   mycroft 			} else
   1198    1.9   mycroft 				len = m->m_len;
   1199    1.9   mycroft 		}
   1200  1.181      maxv 
   1201    1.9   mycroft 		if (copy)
   1202  1.119  christos 			copy(cp, mtod(m, void *), (size_t)len);
   1203    1.9   mycroft 		else
   1204  1.119  christos 			memcpy(mtod(m, void *), cp, (size_t)len);
   1205  1.181      maxv 
   1206    1.9   mycroft 		cp += len;
   1207    1.9   mycroft 		*mp = m;
   1208    1.9   mycroft 		mp = &m->m_next;
   1209    1.9   mycroft 		totlen -= len;
   1210    1.9   mycroft 		if (cp == epkt)
   1211    1.9   mycroft 			cp = buf;
   1212    1.9   mycroft 	}
   1213  1.181      maxv 
   1214  1.181      maxv 	return top;
   1215   1.18   thorpej }
   1216   1.18   thorpej 
   1217   1.18   thorpej /*
   1218   1.18   thorpej  * Copy data from a buffer back into the indicated mbuf chain,
   1219   1.18   thorpej  * starting "off" bytes from the beginning, extending the mbuf
   1220   1.18   thorpej  * chain if necessary.
   1221   1.18   thorpej  */
   1222   1.18   thorpej void
   1223   1.86      yamt m_copyback(struct mbuf *m0, int off, int len, const void *cp)
   1224   1.18   thorpej {
   1225   1.85      yamt #if defined(DEBUG)
   1226   1.85      yamt 	struct mbuf *origm = m0;
   1227   1.85      yamt 	int error;
   1228  1.181      maxv #endif
   1229   1.85      yamt 
   1230   1.85      yamt 	if (m0 == NULL)
   1231   1.85      yamt 		return;
   1232   1.85      yamt 
   1233   1.85      yamt #if defined(DEBUG)
   1234   1.85      yamt 	error =
   1235  1.181      maxv #endif
   1236  1.196      maxv 	m_copyback_internal(&m0, off, len, cp, CB_COPYBACK|CB_EXTEND,
   1237  1.196      maxv 	    M_DONTWAIT);
   1238   1.85      yamt 
   1239   1.85      yamt #if defined(DEBUG)
   1240   1.85      yamt 	if (error != 0 || (m0 != NULL && origm != m0))
   1241   1.85      yamt 		panic("m_copyback");
   1242  1.181      maxv #endif
   1243   1.85      yamt }
   1244   1.85      yamt 
   1245   1.85      yamt struct mbuf *
   1246   1.86      yamt m_copyback_cow(struct mbuf *m0, int off, int len, const void *cp, int how)
   1247   1.85      yamt {
   1248   1.85      yamt 	int error;
   1249   1.85      yamt 
   1250   1.85      yamt 	/* don't support chain expansion */
   1251  1.156  christos 	KASSERT(len != M_COPYALL);
   1252   1.85      yamt 	KDASSERT(off + len <= m_length(m0));
   1253   1.85      yamt 
   1254  1.196      maxv 	error = m_copyback_internal(&m0, off, len, cp, CB_COPYBACK|CB_COW,
   1255  1.196      maxv 	    how);
   1256   1.85      yamt 	if (error) {
   1257   1.85      yamt 		/*
   1258   1.85      yamt 		 * no way to recover from partial success.
   1259   1.85      yamt 		 * just free the chain.
   1260   1.85      yamt 		 */
   1261   1.85      yamt 		m_freem(m0);
   1262   1.85      yamt 		return NULL;
   1263   1.85      yamt 	}
   1264   1.85      yamt 	return m0;
   1265   1.85      yamt }
   1266   1.85      yamt 
   1267   1.85      yamt int
   1268   1.85      yamt m_makewritable(struct mbuf **mp, int off, int len, int how)
   1269   1.85      yamt {
   1270   1.85      yamt 	int error;
   1271   1.85      yamt #if defined(DEBUG)
   1272  1.156  christos 	int origlen = m_length(*mp);
   1273  1.181      maxv #endif
   1274   1.85      yamt 
   1275  1.196      maxv 	error = m_copyback_internal(mp, off, len, NULL, CB_PRESERVE|CB_COW,
   1276  1.196      maxv 	    how);
   1277  1.170  christos 	if (error)
   1278  1.170  christos 		return error;
   1279  1.170  christos 
   1280   1.85      yamt #if defined(DEBUG)
   1281  1.156  christos 	int reslen = 0;
   1282  1.156  christos 	for (struct mbuf *n = *mp; n; n = n->m_next)
   1283   1.85      yamt 		reslen += n->m_len;
   1284   1.85      yamt 	if (origlen != reslen)
   1285   1.85      yamt 		panic("m_makewritable: length changed");
   1286   1.85      yamt 	if (((*mp)->m_flags & M_PKTHDR) != 0 && reslen != (*mp)->m_pkthdr.len)
   1287   1.85      yamt 		panic("m_makewritable: inconsist");
   1288  1.181      maxv #endif
   1289   1.85      yamt 
   1290  1.170  christos 	return 0;
   1291   1.85      yamt }
   1292   1.85      yamt 
   1293  1.142    dyoung /*
   1294  1.142    dyoung  * Copy the mbuf chain to a new mbuf chain that is as short as possible.
   1295  1.142    dyoung  * Return the new mbuf chain on success, NULL on failure.  On success,
   1296  1.142    dyoung  * free the old mbuf chain.
   1297  1.142    dyoung  */
   1298  1.142    dyoung struct mbuf *
   1299  1.142    dyoung m_defrag(struct mbuf *mold, int flags)
   1300  1.142    dyoung {
   1301  1.142    dyoung 	struct mbuf *m0, *mn, *n;
   1302  1.142    dyoung 	size_t sz = mold->m_pkthdr.len;
   1303  1.142    dyoung 
   1304  1.181      maxv 	KASSERT((mold->m_flags & M_PKTHDR) != 0);
   1305  1.142    dyoung 
   1306  1.153  christos 	m0 = m_gethdr(flags, MT_DATA);
   1307  1.142    dyoung 	if (m0 == NULL)
   1308  1.142    dyoung 		return NULL;
   1309  1.142    dyoung 	M_COPY_PKTHDR(m0, mold);
   1310  1.142    dyoung 	mn = m0;
   1311  1.142    dyoung 
   1312  1.142    dyoung 	do {
   1313  1.142    dyoung 		if (sz > MHLEN) {
   1314  1.142    dyoung 			MCLGET(mn, M_DONTWAIT);
   1315  1.142    dyoung 			if ((mn->m_flags & M_EXT) == 0) {
   1316  1.142    dyoung 				m_freem(m0);
   1317  1.142    dyoung 				return NULL;
   1318  1.142    dyoung 			}
   1319  1.142    dyoung 		}
   1320  1.142    dyoung 
   1321  1.142    dyoung 		mn->m_len = MIN(sz, MCLBYTES);
   1322  1.142    dyoung 
   1323  1.142    dyoung 		m_copydata(mold, mold->m_pkthdr.len - sz, mn->m_len,
   1324  1.142    dyoung 		     mtod(mn, void *));
   1325  1.142    dyoung 
   1326  1.142    dyoung 		sz -= mn->m_len;
   1327  1.142    dyoung 
   1328  1.142    dyoung 		if (sz > 0) {
   1329  1.142    dyoung 			/* need more mbufs */
   1330  1.153  christos 			n = m_get(M_NOWAIT, MT_DATA);
   1331  1.142    dyoung 			if (n == NULL) {
   1332  1.142    dyoung 				m_freem(m0);
   1333  1.142    dyoung 				return NULL;
   1334  1.142    dyoung 			}
   1335  1.142    dyoung 
   1336  1.142    dyoung 			mn->m_next = n;
   1337  1.142    dyoung 			mn = n;
   1338  1.142    dyoung 		}
   1339  1.142    dyoung 	} while (sz > 0);
   1340  1.142    dyoung 
   1341  1.142    dyoung 	m_freem(mold);
   1342  1.142    dyoung 
   1343  1.142    dyoung 	return m0;
   1344  1.142    dyoung }
   1345  1.142    dyoung 
   1346  1.196      maxv static int
   1347  1.196      maxv m_copyback_internal(struct mbuf **mp0, int off, int len, const void *vp,
   1348  1.196      maxv     int flags, int how)
   1349   1.85      yamt {
   1350   1.27      matt 	int mlen;
   1351   1.85      yamt 	struct mbuf *m, *n;
   1352   1.85      yamt 	struct mbuf **mp;
   1353   1.18   thorpej 	int totlen = 0;
   1354   1.86      yamt 	const char *cp = vp;
   1355   1.18   thorpej 
   1356   1.85      yamt 	KASSERT(mp0 != NULL);
   1357   1.85      yamt 	KASSERT(*mp0 != NULL);
   1358  1.196      maxv 	KASSERT((flags & CB_PRESERVE) == 0 || cp == NULL);
   1359  1.196      maxv 	KASSERT((flags & CB_COPYBACK) == 0 || cp != NULL);
   1360   1.85      yamt 
   1361  1.156  christos 	if (len == M_COPYALL)
   1362  1.156  christos 		len = m_length(*mp0) - off;
   1363  1.156  christos 
   1364  1.106      yamt 	/*
   1365  1.196      maxv 	 * we don't bother to update "totlen" in the case of CB_COW,
   1366  1.196      maxv 	 * assuming that CB_EXTEND and CB_COW are exclusive.
   1367  1.106      yamt 	 */
   1368  1.106      yamt 
   1369  1.196      maxv 	KASSERT((~flags & (CB_EXTEND|CB_COW)) != 0);
   1370  1.106      yamt 
   1371   1.85      yamt 	mp = mp0;
   1372   1.85      yamt 	m = *mp;
   1373   1.18   thorpej 	while (off > (mlen = m->m_len)) {
   1374   1.18   thorpej 		off -= mlen;
   1375   1.18   thorpej 		totlen += mlen;
   1376  1.109      yamt 		if (m->m_next == NULL) {
   1377  1.109      yamt 			int tspace;
   1378  1.109      yamt extend:
   1379  1.196      maxv 			if ((flags & CB_EXTEND) == 0)
   1380   1.85      yamt 				goto out;
   1381  1.109      yamt 
   1382  1.109      yamt 			/*
   1383  1.109      yamt 			 * try to make some space at the end of "m".
   1384  1.109      yamt 			 */
   1385  1.109      yamt 
   1386  1.109      yamt 			mlen = m->m_len;
   1387  1.109      yamt 			if (off + len >= MINCLSIZE &&
   1388  1.109      yamt 			    (m->m_flags & M_EXT) == 0 && m->m_len == 0) {
   1389  1.109      yamt 				MCLGET(m, how);
   1390  1.109      yamt 			}
   1391  1.109      yamt 			tspace = M_TRAILINGSPACE(m);
   1392  1.109      yamt 			if (tspace > 0) {
   1393  1.109      yamt 				tspace = min(tspace, off + len);
   1394  1.109      yamt 				KASSERT(tspace > 0);
   1395  1.109      yamt 				memset(mtod(m, char *) + m->m_len, 0,
   1396  1.109      yamt 				    min(off, tspace));
   1397  1.109      yamt 				m->m_len += tspace;
   1398  1.109      yamt 				off += mlen;
   1399  1.109      yamt 				totlen -= mlen;
   1400  1.109      yamt 				continue;
   1401  1.109      yamt 			}
   1402  1.109      yamt 
   1403  1.109      yamt 			/*
   1404  1.109      yamt 			 * need to allocate an mbuf.
   1405  1.109      yamt 			 */
   1406  1.109      yamt 
   1407  1.109      yamt 			if (off + len >= MINCLSIZE) {
   1408  1.109      yamt 				n = m_getcl(how, m->m_type, 0);
   1409  1.109      yamt 			} else {
   1410  1.109      yamt 				n = m_get(how, m->m_type);
   1411  1.109      yamt 			}
   1412  1.109      yamt 			if (n == NULL) {
   1413   1.18   thorpej 				goto out;
   1414  1.109      yamt 			}
   1415  1.109      yamt 			n->m_len = min(M_TRAILINGSPACE(n), off + len);
   1416  1.109      yamt 			memset(mtod(n, char *), 0, min(n->m_len, off));
   1417   1.18   thorpej 			m->m_next = n;
   1418   1.18   thorpej 		}
   1419   1.85      yamt 		mp = &m->m_next;
   1420   1.18   thorpej 		m = m->m_next;
   1421   1.18   thorpej 	}
   1422   1.18   thorpej 	while (len > 0) {
   1423   1.85      yamt 		mlen = m->m_len - off;
   1424   1.85      yamt 		if (mlen != 0 && M_READONLY(m)) {
   1425  1.196      maxv 			/*
   1426  1.196      maxv 			 * This mbuf is read-only. Allocate a new writable
   1427  1.196      maxv 			 * mbuf and try again.
   1428  1.196      maxv 			 */
   1429   1.85      yamt 			char *datap;
   1430   1.85      yamt 			int eatlen;
   1431   1.85      yamt 
   1432  1.196      maxv 			KASSERT((flags & CB_COW) != 0);
   1433   1.85      yamt 
   1434   1.85      yamt 			/*
   1435   1.85      yamt 			 * if we're going to write into the middle of
   1436   1.85      yamt 			 * a mbuf, split it first.
   1437   1.85      yamt 			 */
   1438  1.137     seanb 			if (off > 0) {
   1439  1.195      maxv 				n = m_split_internal(m, off, how, false);
   1440   1.85      yamt 				if (n == NULL)
   1441   1.85      yamt 					goto enobufs;
   1442   1.85      yamt 				m->m_next = n;
   1443   1.85      yamt 				mp = &m->m_next;
   1444   1.85      yamt 				m = n;
   1445   1.85      yamt 				off = 0;
   1446   1.85      yamt 				continue;
   1447   1.85      yamt 			}
   1448   1.85      yamt 
   1449   1.85      yamt 			/*
   1450   1.85      yamt 			 * XXX TODO coalesce into the trailingspace of
   1451   1.85      yamt 			 * the previous mbuf when possible.
   1452   1.85      yamt 			 */
   1453   1.85      yamt 
   1454   1.85      yamt 			/*
   1455   1.85      yamt 			 * allocate a new mbuf.  copy packet header if needed.
   1456   1.85      yamt 			 */
   1457  1.153  christos 			n = m_get(how, m->m_type);
   1458   1.85      yamt 			if (n == NULL)
   1459   1.85      yamt 				goto enobufs;
   1460   1.85      yamt 			MCLAIM(n, m->m_owner);
   1461   1.85      yamt 			if (off == 0 && (m->m_flags & M_PKTHDR) != 0) {
   1462  1.101      yamt 				M_MOVE_PKTHDR(n, m);
   1463   1.85      yamt 				n->m_len = MHLEN;
   1464   1.85      yamt 			} else {
   1465   1.85      yamt 				if (len >= MINCLSIZE)
   1466   1.85      yamt 					MCLGET(n, M_DONTWAIT);
   1467   1.85      yamt 				n->m_len =
   1468   1.85      yamt 				    (n->m_flags & M_EXT) ? MCLBYTES : MLEN;
   1469   1.85      yamt 			}
   1470   1.85      yamt 			if (n->m_len > len)
   1471   1.85      yamt 				n->m_len = len;
   1472   1.85      yamt 
   1473   1.85      yamt 			/*
   1474   1.85      yamt 			 * free the region which has been overwritten.
   1475   1.85      yamt 			 * copying data from old mbufs if requested.
   1476   1.85      yamt 			 */
   1477  1.196      maxv 			if (flags & CB_PRESERVE)
   1478   1.85      yamt 				datap = mtod(n, char *);
   1479   1.85      yamt 			else
   1480   1.85      yamt 				datap = NULL;
   1481   1.85      yamt 			eatlen = n->m_len;
   1482   1.85      yamt 			while (m != NULL && M_READONLY(m) &&
   1483   1.85      yamt 			    n->m_type == m->m_type && eatlen > 0) {
   1484   1.85      yamt 				mlen = min(eatlen, m->m_len);
   1485   1.85      yamt 				if (datap) {
   1486   1.85      yamt 					m_copydata(m, 0, mlen, datap);
   1487   1.85      yamt 					datap += mlen;
   1488   1.85      yamt 				}
   1489   1.85      yamt 				m->m_data += mlen;
   1490   1.85      yamt 				m->m_len -= mlen;
   1491   1.85      yamt 				eatlen -= mlen;
   1492   1.85      yamt 				if (m->m_len == 0)
   1493   1.85      yamt 					*mp = m = m_free(m);
   1494   1.85      yamt 			}
   1495   1.85      yamt 			if (eatlen > 0)
   1496   1.85      yamt 				n->m_len -= eatlen;
   1497   1.85      yamt 			n->m_next = m;
   1498   1.85      yamt 			*mp = m = n;
   1499   1.85      yamt 			continue;
   1500   1.85      yamt 		}
   1501   1.85      yamt 		mlen = min(mlen, len);
   1502  1.196      maxv 		if (flags & CB_COPYBACK) {
   1503  1.119  christos 			memcpy(mtod(m, char *) + off, cp, (unsigned)mlen);
   1504   1.85      yamt 			cp += mlen;
   1505   1.85      yamt 		}
   1506   1.18   thorpej 		len -= mlen;
   1507   1.18   thorpej 		mlen += off;
   1508   1.18   thorpej 		off = 0;
   1509   1.18   thorpej 		totlen += mlen;
   1510   1.18   thorpej 		if (len == 0)
   1511   1.18   thorpej 			break;
   1512  1.109      yamt 		if (m->m_next == NULL) {
   1513  1.109      yamt 			goto extend;
   1514   1.18   thorpej 		}
   1515   1.85      yamt 		mp = &m->m_next;
   1516   1.18   thorpej 		m = m->m_next;
   1517   1.18   thorpej 	}
   1518  1.199      maxv 
   1519  1.199      maxv out:
   1520  1.199      maxv 	if (((m = *mp0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) {
   1521  1.196      maxv 		KASSERT((flags & CB_EXTEND) != 0);
   1522   1.18   thorpej 		m->m_pkthdr.len = totlen;
   1523  1.106      yamt 	}
   1524   1.85      yamt 
   1525   1.85      yamt 	return 0;
   1526   1.85      yamt 
   1527   1.85      yamt enobufs:
   1528   1.85      yamt 	return ENOBUFS;
   1529   1.66   thorpej }
   1530   1.66   thorpej 
   1531  1.101      yamt void
   1532  1.202      maxv m_copy_pkthdr(struct mbuf *to, struct mbuf *from)
   1533  1.202      maxv {
   1534  1.202      maxv 	KASSERT((from->m_flags & M_PKTHDR) != 0);
   1535  1.202      maxv 
   1536  1.202      maxv 	to->m_pkthdr = from->m_pkthdr;
   1537  1.202      maxv 	to->m_flags = from->m_flags & M_COPYFLAGS;
   1538  1.202      maxv 	SLIST_INIT(&to->m_pkthdr.tags);
   1539  1.202      maxv 	m_tag_copy_chain(to, from);
   1540  1.202      maxv 	to->m_data = to->m_pktdat;
   1541  1.202      maxv }
   1542  1.202      maxv 
   1543  1.202      maxv void
   1544  1.101      yamt m_move_pkthdr(struct mbuf *to, struct mbuf *from)
   1545  1.101      yamt {
   1546  1.101      yamt 
   1547  1.101      yamt 	KASSERT((to->m_flags & M_EXT) == 0);
   1548  1.101      yamt 	KASSERT((to->m_flags & M_PKTHDR) == 0 || m_tag_first(to) == NULL);
   1549  1.101      yamt 	KASSERT((from->m_flags & M_PKTHDR) != 0);
   1550  1.101      yamt 
   1551  1.101      yamt 	to->m_pkthdr = from->m_pkthdr;
   1552  1.101      yamt 	to->m_flags = from->m_flags & M_COPYFLAGS;
   1553  1.101      yamt 	to->m_data = to->m_pktdat;
   1554  1.101      yamt 
   1555  1.101      yamt 	from->m_flags &= ~M_PKTHDR;
   1556  1.101      yamt }
   1557  1.101      yamt 
   1558   1.66   thorpej /*
   1559   1.66   thorpej  * Apply function f to the data in an mbuf chain starting "off" bytes from the
   1560   1.66   thorpej  * beginning, continuing for "len" bytes.
   1561   1.66   thorpej  */
   1562   1.66   thorpej int
   1563   1.66   thorpej m_apply(struct mbuf *m, int off, int len,
   1564  1.119  christos     int (*f)(void *, void *, unsigned int), void *arg)
   1565   1.66   thorpej {
   1566   1.66   thorpej 	unsigned int count;
   1567   1.66   thorpej 	int rval;
   1568   1.66   thorpej 
   1569  1.156  christos 	KASSERT(len != M_COPYALL);
   1570   1.66   thorpej 	KASSERT(len >= 0);
   1571   1.66   thorpej 	KASSERT(off >= 0);
   1572   1.66   thorpej 
   1573   1.66   thorpej 	while (off > 0) {
   1574   1.66   thorpej 		KASSERT(m != NULL);
   1575   1.66   thorpej 		if (off < m->m_len)
   1576   1.66   thorpej 			break;
   1577   1.66   thorpej 		off -= m->m_len;
   1578   1.66   thorpej 		m = m->m_next;
   1579   1.66   thorpej 	}
   1580   1.66   thorpej 	while (len > 0) {
   1581   1.66   thorpej 		KASSERT(m != NULL);
   1582   1.66   thorpej 		count = min(m->m_len - off, len);
   1583   1.66   thorpej 
   1584  1.119  christos 		rval = (*f)(arg, mtod(m, char *) + off, count);
   1585   1.66   thorpej 		if (rval)
   1586  1.181      maxv 			return rval;
   1587   1.66   thorpej 
   1588   1.66   thorpej 		len -= count;
   1589   1.66   thorpej 		off = 0;
   1590   1.66   thorpej 		m = m->m_next;
   1591   1.66   thorpej 	}
   1592   1.66   thorpej 
   1593  1.181      maxv 	return 0;
   1594   1.66   thorpej }
   1595   1.66   thorpej 
   1596   1.66   thorpej /*
   1597   1.66   thorpej  * Return a pointer to mbuf/offset of location in mbuf chain.
   1598   1.66   thorpej  */
   1599   1.66   thorpej struct mbuf *
   1600   1.66   thorpej m_getptr(struct mbuf *m, int loc, int *off)
   1601   1.66   thorpej {
   1602   1.66   thorpej 
   1603   1.66   thorpej 	while (loc >= 0) {
   1604   1.66   thorpej 		/* Normal end of search */
   1605   1.66   thorpej 		if (m->m_len > loc) {
   1606  1.177      maxv 			*off = loc;
   1607  1.181      maxv 			return m;
   1608  1.181      maxv 		}
   1609  1.181      maxv 
   1610  1.181      maxv 		loc -= m->m_len;
   1611  1.181      maxv 
   1612  1.181      maxv 		if (m->m_next == NULL) {
   1613  1.181      maxv 			if (loc == 0) {
   1614  1.181      maxv 				/* Point at the end of valid data */
   1615  1.181      maxv 				*off = m->m_len;
   1616  1.181      maxv 				return m;
   1617  1.181      maxv 			}
   1618  1.181      maxv 			return NULL;
   1619   1.66   thorpej 		} else {
   1620  1.181      maxv 			m = m->m_next;
   1621   1.66   thorpej 		}
   1622  1.177      maxv 	}
   1623   1.66   thorpej 
   1624  1.181      maxv 	return NULL;
   1625    1.1       cgd }
   1626  1.105      yamt 
   1627  1.105      yamt #if defined(DDB)
   1628  1.105      yamt void
   1629  1.105      yamt m_print(const struct mbuf *m, const char *modif, void (*pr)(const char *, ...))
   1630  1.105      yamt {
   1631  1.105      yamt 	char ch;
   1632  1.118   thorpej 	bool opt_c = false;
   1633  1.105      yamt 	char buf[512];
   1634  1.105      yamt 
   1635  1.105      yamt 	while ((ch = *(modif++)) != '\0') {
   1636  1.105      yamt 		switch (ch) {
   1637  1.105      yamt 		case 'c':
   1638  1.118   thorpej 			opt_c = true;
   1639  1.105      yamt 			break;
   1640  1.105      yamt 		}
   1641  1.105      yamt 	}
   1642  1.105      yamt 
   1643  1.105      yamt nextchain:
   1644  1.105      yamt 	(*pr)("MBUF %p\n", m);
   1645  1.130  christos 	snprintb(buf, sizeof(buf), M_FLAGS_BITS, (u_int)m->m_flags);
   1646  1.138    cegger 	(*pr)("  data=%p, len=%d, type=%d, flags=%s\n",
   1647  1.105      yamt 	    m->m_data, m->m_len, m->m_type, buf);
   1648  1.105      yamt 	(*pr)("  owner=%p, next=%p, nextpkt=%p\n", m->m_owner, m->m_next,
   1649  1.105      yamt 	    m->m_nextpkt);
   1650  1.105      yamt 	(*pr)("  leadingspace=%u, trailingspace=%u, readonly=%u\n",
   1651  1.105      yamt 	    (int)M_LEADINGSPACE(m), (int)M_TRAILINGSPACE(m),
   1652  1.105      yamt 	    (int)M_READONLY(m));
   1653  1.105      yamt 	if ((m->m_flags & M_PKTHDR) != 0) {
   1654  1.130  christos 		snprintb(buf, sizeof(buf), M_CSUM_BITS, m->m_pkthdr.csum_flags);
   1655  1.172   msaitoh 		(*pr)("  pktlen=%d, rcvif=%p, csum_flags=%s, csum_data=0x%"
   1656  1.105      yamt 		    PRIx32 ", segsz=%u\n",
   1657  1.167     ozaki 		    m->m_pkthdr.len, m_get_rcvif_NOMPSAFE(m),
   1658  1.105      yamt 		    buf, m->m_pkthdr.csum_data, m->m_pkthdr.segsz);
   1659  1.105      yamt 	}
   1660  1.105      yamt 	if ((m->m_flags & M_EXT)) {
   1661  1.125      yamt 		(*pr)("  ext_refcnt=%u, ext_buf=%p, ext_size=%zd, "
   1662  1.105      yamt 		    "ext_free=%p, ext_arg=%p\n",
   1663  1.125      yamt 		    m->m_ext.ext_refcnt,
   1664  1.105      yamt 		    m->m_ext.ext_buf, m->m_ext.ext_size,
   1665  1.105      yamt 		    m->m_ext.ext_free, m->m_ext.ext_arg);
   1666  1.105      yamt 	}
   1667  1.105      yamt 	if ((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0) {
   1668  1.108      yamt 		vaddr_t sva = (vaddr_t)m->m_ext.ext_buf;
   1669  1.108      yamt 		vaddr_t eva = sva + m->m_ext.ext_size;
   1670  1.108      yamt 		int n = (round_page(eva) - trunc_page(sva)) >> PAGE_SHIFT;
   1671  1.108      yamt 		int i;
   1672  1.105      yamt 
   1673  1.105      yamt 		(*pr)("  pages:");
   1674  1.108      yamt 		for (i = 0; i < n; i ++) {
   1675  1.108      yamt 			(*pr)(" %p", m->m_ext.ext_pgs[i]);
   1676  1.105      yamt 		}
   1677  1.105      yamt 		(*pr)("\n");
   1678  1.105      yamt 	}
   1679  1.105      yamt 
   1680  1.105      yamt 	if (opt_c) {
   1681  1.105      yamt 		m = m->m_next;
   1682  1.105      yamt 		if (m != NULL) {
   1683  1.105      yamt 			goto nextchain;
   1684  1.105      yamt 		}
   1685  1.105      yamt 	}
   1686  1.105      yamt }
   1687  1.105      yamt #endif /* defined(DDB) */
   1688  1.124      yamt 
   1689  1.124      yamt void
   1690  1.124      yamt mbstat_type_add(int type, int diff)
   1691  1.124      yamt {
   1692  1.124      yamt 	struct mbstat_cpu *mb;
   1693  1.124      yamt 	int s;
   1694  1.124      yamt 
   1695  1.124      yamt 	s = splvm();
   1696  1.126   thorpej 	mb = percpu_getref(mbstat_percpu);
   1697  1.124      yamt 	mb->m_mtypes[type] += diff;
   1698  1.126   thorpej 	percpu_putref(mbstat_percpu);
   1699  1.124      yamt 	splx(s);
   1700  1.124      yamt }
   1701  1.124      yamt 
   1702  1.124      yamt #if defined(MBUFTRACE)
   1703  1.124      yamt void
   1704  1.124      yamt mowner_attach(struct mowner *mo)
   1705  1.124      yamt {
   1706  1.124      yamt 
   1707  1.124      yamt 	KASSERT(mo->mo_counters == NULL);
   1708  1.124      yamt 	mo->mo_counters = percpu_alloc(sizeof(struct mowner_counter));
   1709  1.124      yamt 
   1710  1.124      yamt 	/* XXX lock */
   1711  1.124      yamt 	LIST_INSERT_HEAD(&mowners, mo, mo_link);
   1712  1.124      yamt }
   1713  1.124      yamt 
   1714  1.124      yamt void
   1715  1.124      yamt mowner_detach(struct mowner *mo)
   1716  1.124      yamt {
   1717  1.124      yamt 
   1718  1.124      yamt 	KASSERT(mo->mo_counters != NULL);
   1719  1.124      yamt 
   1720  1.124      yamt 	/* XXX lock */
   1721  1.124      yamt 	LIST_REMOVE(mo, mo_link);
   1722  1.124      yamt 
   1723  1.124      yamt 	percpu_free(mo->mo_counters, sizeof(struct mowner_counter));
   1724  1.124      yamt 	mo->mo_counters = NULL;
   1725  1.124      yamt }
   1726  1.124      yamt 
   1727  1.124      yamt void
   1728  1.124      yamt mowner_init(struct mbuf *m, int type)
   1729  1.124      yamt {
   1730  1.124      yamt 	struct mowner_counter *mc;
   1731  1.124      yamt 	struct mowner *mo;
   1732  1.124      yamt 	int s;
   1733  1.124      yamt 
   1734  1.124      yamt 	m->m_owner = mo = &unknown_mowners[type];
   1735  1.124      yamt 	s = splvm();
   1736  1.126   thorpej 	mc = percpu_getref(mo->mo_counters);
   1737  1.124      yamt 	mc->mc_counter[MOWNER_COUNTER_CLAIMS]++;
   1738  1.126   thorpej 	percpu_putref(mo->mo_counters);
   1739  1.124      yamt 	splx(s);
   1740  1.124      yamt }
   1741  1.124      yamt 
   1742  1.124      yamt void
   1743  1.124      yamt mowner_ref(struct mbuf *m, int flags)
   1744  1.124      yamt {
   1745  1.124      yamt 	struct mowner *mo = m->m_owner;
   1746  1.124      yamt 	struct mowner_counter *mc;
   1747  1.124      yamt 	int s;
   1748  1.124      yamt 
   1749  1.124      yamt 	s = splvm();
   1750  1.126   thorpej 	mc = percpu_getref(mo->mo_counters);
   1751  1.124      yamt 	if ((flags & M_EXT) != 0)
   1752  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_EXT_CLAIMS]++;
   1753  1.124      yamt 	if ((flags & M_CLUSTER) != 0)
   1754  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_CLUSTER_CLAIMS]++;
   1755  1.126   thorpej 	percpu_putref(mo->mo_counters);
   1756  1.124      yamt 	splx(s);
   1757  1.124      yamt }
   1758  1.124      yamt 
   1759  1.124      yamt void
   1760  1.124      yamt mowner_revoke(struct mbuf *m, bool all, int flags)
   1761  1.124      yamt {
   1762  1.124      yamt 	struct mowner *mo = m->m_owner;
   1763  1.124      yamt 	struct mowner_counter *mc;
   1764  1.124      yamt 	int s;
   1765  1.124      yamt 
   1766  1.124      yamt 	s = splvm();
   1767  1.126   thorpej 	mc = percpu_getref(mo->mo_counters);
   1768  1.124      yamt 	if ((flags & M_EXT) != 0)
   1769  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_EXT_RELEASES]++;
   1770  1.124      yamt 	if ((flags & M_CLUSTER) != 0)
   1771  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_CLUSTER_RELEASES]++;
   1772  1.124      yamt 	if (all)
   1773  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_RELEASES]++;
   1774  1.126   thorpej 	percpu_putref(mo->mo_counters);
   1775  1.124      yamt 	splx(s);
   1776  1.124      yamt 	if (all)
   1777  1.124      yamt 		m->m_owner = &revoked_mowner;
   1778  1.124      yamt }
   1779  1.124      yamt 
   1780  1.124      yamt static void
   1781  1.124      yamt mowner_claim(struct mbuf *m, struct mowner *mo)
   1782  1.124      yamt {
   1783  1.124      yamt 	struct mowner_counter *mc;
   1784  1.124      yamt 	int flags = m->m_flags;
   1785  1.124      yamt 	int s;
   1786  1.124      yamt 
   1787  1.124      yamt 	s = splvm();
   1788  1.126   thorpej 	mc = percpu_getref(mo->mo_counters);
   1789  1.124      yamt 	mc->mc_counter[MOWNER_COUNTER_CLAIMS]++;
   1790  1.124      yamt 	if ((flags & M_EXT) != 0)
   1791  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_EXT_CLAIMS]++;
   1792  1.124      yamt 	if ((flags & M_CLUSTER) != 0)
   1793  1.124      yamt 		mc->mc_counter[MOWNER_COUNTER_CLUSTER_CLAIMS]++;
   1794  1.126   thorpej 	percpu_putref(mo->mo_counters);
   1795  1.124      yamt 	splx(s);
   1796  1.124      yamt 	m->m_owner = mo;
   1797  1.124      yamt }
   1798  1.124      yamt 
   1799  1.124      yamt void
   1800  1.124      yamt m_claim(struct mbuf *m, struct mowner *mo)
   1801  1.124      yamt {
   1802  1.124      yamt 
   1803  1.124      yamt 	if (m->m_owner == mo || mo == NULL)
   1804  1.124      yamt 		return;
   1805  1.124      yamt 
   1806  1.124      yamt 	mowner_revoke(m, true, m->m_flags);
   1807  1.124      yamt 	mowner_claim(m, mo);
   1808  1.124      yamt }
   1809  1.124      yamt #endif /* defined(MBUFTRACE) */
   1810  1.169  christos 
   1811  1.188      maxv #ifdef DIAGNOSTIC
   1812  1.188      maxv /*
   1813  1.188      maxv  * Verify that the mbuf chain is not malformed. Used only for diagnostic.
   1814  1.188      maxv  * Panics on error.
   1815  1.188      maxv  */
   1816  1.188      maxv void
   1817  1.188      maxv m_verify_packet(struct mbuf *m)
   1818  1.188      maxv {
   1819  1.188      maxv 	struct mbuf *n = m;
   1820  1.188      maxv 	char *low, *high, *dat;
   1821  1.188      maxv 	int totlen = 0, len;
   1822  1.188      maxv 
   1823  1.188      maxv 	if (__predict_false((m->m_flags & M_PKTHDR) == 0)) {
   1824  1.188      maxv 		panic("%s: mbuf doesn't have M_PKTHDR", __func__);
   1825  1.188      maxv 	}
   1826  1.188      maxv 
   1827  1.188      maxv 	while (n != NULL) {
   1828  1.188      maxv 		if (__predict_false(n->m_type == MT_FREE)) {
   1829  1.188      maxv 			panic("%s: mbuf already freed (n = %p)", __func__, n);
   1830  1.188      maxv 		}
   1831  1.191      maxv #if 0
   1832  1.191      maxv 		/*
   1833  1.191      maxv 		 * This ought to be a rule of the mbuf API. Unfortunately,
   1834  1.191      maxv 		 * many places don't respect that rule.
   1835  1.191      maxv 		 */
   1836  1.188      maxv 		if (__predict_false((n != m) && (n->m_flags & M_PKTHDR) != 0)) {
   1837  1.188      maxv 			panic("%s: M_PKTHDR set on secondary mbuf", __func__);
   1838  1.188      maxv 		}
   1839  1.189      maxv #endif
   1840  1.188      maxv 		if (__predict_false(n->m_nextpkt != NULL)) {
   1841  1.188      maxv 			panic("%s: m_nextpkt not null (m_nextpkt = %p)",
   1842  1.188      maxv 			    __func__, n->m_nextpkt);
   1843  1.188      maxv 		}
   1844  1.188      maxv 
   1845  1.188      maxv 		dat = n->m_data;
   1846  1.188      maxv 		len = n->m_len;
   1847  1.188      maxv 
   1848  1.188      maxv 		if (n->m_flags & M_EXT) {
   1849  1.188      maxv 			low = n->m_ext.ext_buf;
   1850  1.188      maxv 			high = low + n->m_ext.ext_size;
   1851  1.188      maxv 		} else if (n->m_flags & M_PKTHDR) {
   1852  1.188      maxv 			low = n->m_pktdat;
   1853  1.188      maxv 			high = low + MHLEN;
   1854  1.188      maxv 		} else {
   1855  1.188      maxv 			low = n->m_dat;
   1856  1.188      maxv 			high = low + MLEN;
   1857  1.188      maxv 		}
   1858  1.192      maxv 		if (__predict_false(dat + len < dat)) {
   1859  1.188      maxv 			panic("%s: incorrect length (len = %d)", __func__, len);
   1860  1.188      maxv 		}
   1861  1.188      maxv 		if (__predict_false((dat < low) || (dat + len > high))) {
   1862  1.188      maxv 			panic("%s: m_data not in packet"
   1863  1.188      maxv 			    "(dat = %p, len = %d, low = %p, high = %p)",
   1864  1.188      maxv 			    __func__, dat, len, low, high);
   1865  1.188      maxv 		}
   1866  1.188      maxv 
   1867  1.188      maxv 		totlen += len;
   1868  1.188      maxv 		n = n->m_next;
   1869  1.188      maxv 	}
   1870  1.188      maxv 
   1871  1.188      maxv 	if (__predict_false(totlen != m->m_pkthdr.len)) {
   1872  1.188      maxv 		panic("%s: inconsistent mbuf length (%d != %d)", __func__,
   1873  1.188      maxv 		    totlen, m->m_pkthdr.len);
   1874  1.188      maxv 	}
   1875  1.188      maxv }
   1876  1.188      maxv #endif
   1877  1.188      maxv 
   1878  1.169  christos /*
   1879  1.186      maxv  * Release a reference to the mbuf external storage.
   1880  1.186      maxv  *
   1881  1.186      maxv  * => free the mbuf m itself as well.
   1882  1.186      maxv  */
   1883  1.186      maxv static void
   1884  1.186      maxv m_ext_free(struct mbuf *m)
   1885  1.186      maxv {
   1886  1.186      maxv 	const bool embedded = MEXT_ISEMBEDDED(m);
   1887  1.186      maxv 	bool dofree = true;
   1888  1.186      maxv 	u_int refcnt;
   1889  1.186      maxv 
   1890  1.186      maxv 	KASSERT((m->m_flags & M_EXT) != 0);
   1891  1.186      maxv 	KASSERT(MEXT_ISEMBEDDED(m->m_ext_ref));
   1892  1.186      maxv 	KASSERT((m->m_ext_ref->m_flags & M_EXT) != 0);
   1893  1.186      maxv 	KASSERT((m->m_flags & M_EXT_CLUSTER) ==
   1894  1.186      maxv 	    (m->m_ext_ref->m_flags & M_EXT_CLUSTER));
   1895  1.186      maxv 
   1896  1.186      maxv 	if (__predict_false(m->m_type == MT_FREE)) {
   1897  1.186      maxv 		panic("mbuf %p already freed", m);
   1898  1.186      maxv 	}
   1899  1.186      maxv 
   1900  1.186      maxv 	if (__predict_true(m->m_ext.ext_refcnt == 1)) {
   1901  1.186      maxv 		refcnt = m->m_ext.ext_refcnt = 0;
   1902  1.186      maxv 	} else {
   1903  1.186      maxv 		refcnt = atomic_dec_uint_nv(&m->m_ext.ext_refcnt);
   1904  1.186      maxv 	}
   1905  1.186      maxv 
   1906  1.186      maxv 	if (refcnt > 0) {
   1907  1.186      maxv 		if (embedded) {
   1908  1.186      maxv 			/*
   1909  1.186      maxv 			 * other mbuf's m_ext_ref still points to us.
   1910  1.186      maxv 			 */
   1911  1.186      maxv 			dofree = false;
   1912  1.186      maxv 		} else {
   1913  1.186      maxv 			m->m_ext_ref = m;
   1914  1.186      maxv 		}
   1915  1.186      maxv 	} else {
   1916  1.186      maxv 		/*
   1917  1.186      maxv 		 * dropping the last reference
   1918  1.186      maxv 		 */
   1919  1.186      maxv 		if (!embedded) {
   1920  1.186      maxv 			m->m_ext.ext_refcnt++; /* XXX */
   1921  1.186      maxv 			m_ext_free(m->m_ext_ref);
   1922  1.186      maxv 			m->m_ext_ref = m;
   1923  1.186      maxv 		} else if ((m->m_flags & M_EXT_CLUSTER) != 0) {
   1924  1.186      maxv 			pool_cache_put_paddr((struct pool_cache *)
   1925  1.186      maxv 			    m->m_ext.ext_arg,
   1926  1.186      maxv 			    m->m_ext.ext_buf, m->m_ext.ext_paddr);
   1927  1.186      maxv 		} else if (m->m_ext.ext_free) {
   1928  1.186      maxv 			(*m->m_ext.ext_free)(m,
   1929  1.186      maxv 			    m->m_ext.ext_buf, m->m_ext.ext_size,
   1930  1.186      maxv 			    m->m_ext.ext_arg);
   1931  1.186      maxv 			/*
   1932  1.186      maxv 			 * 'm' is already freed by the ext_free callback.
   1933  1.186      maxv 			 */
   1934  1.186      maxv 			dofree = false;
   1935  1.186      maxv 		} else {
   1936  1.186      maxv 			free(m->m_ext.ext_buf, m->m_ext.ext_type);
   1937  1.186      maxv 		}
   1938  1.186      maxv 	}
   1939  1.186      maxv 
   1940  1.186      maxv 	if (dofree) {
   1941  1.186      maxv 		m->m_type = MT_FREE;
   1942  1.186      maxv 		m->m_data = NULL;
   1943  1.186      maxv 		pool_cache_put(mb_cache, m);
   1944  1.186      maxv 	}
   1945  1.186      maxv }
   1946  1.186      maxv 
   1947  1.186      maxv /*
   1948  1.175      maxv  * Free a single mbuf and associated external storage. Return the
   1949  1.175      maxv  * successor, if any.
   1950  1.175      maxv  */
   1951  1.169  christos struct mbuf *
   1952  1.175      maxv m_free(struct mbuf *m)
   1953  1.169  christos {
   1954  1.169  christos 	struct mbuf *n;
   1955  1.169  christos 
   1956  1.175      maxv 	mowner_revoke(m, 1, m->m_flags);
   1957  1.175      maxv 	mbstat_type_add(m->m_type, -1);
   1958  1.175      maxv 
   1959  1.175      maxv 	if (m->m_flags & M_PKTHDR)
   1960  1.175      maxv 		m_tag_delete_chain(m, NULL);
   1961  1.175      maxv 
   1962  1.175      maxv 	n = m->m_next;
   1963  1.175      maxv 
   1964  1.175      maxv 	if (m->m_flags & M_EXT) {
   1965  1.175      maxv 		m_ext_free(m);
   1966  1.175      maxv 	} else {
   1967  1.175      maxv 		if (__predict_false(m->m_type == MT_FREE)) {
   1968  1.175      maxv 			panic("mbuf %p already freed", m);
   1969  1.175      maxv 		}
   1970  1.175      maxv 		m->m_type = MT_FREE;
   1971  1.175      maxv 		m->m_data = NULL;
   1972  1.175      maxv 		pool_cache_put(mb_cache, m);
   1973  1.175      maxv 	}
   1974  1.175      maxv 
   1975  1.175      maxv 	return n;
   1976  1.169  christos }
   1977  1.169  christos 
   1978  1.169  christos void
   1979  1.175      maxv m_freem(struct mbuf *m)
   1980  1.169  christos {
   1981  1.169  christos 	if (m == NULL)
   1982  1.169  christos 		return;
   1983  1.169  christos 	do {
   1984  1.175      maxv 		m = m_free(m);
   1985  1.169  christos 	} while (m);
   1986  1.169  christos }
   1987