4 * Copyright (c) 2004 Jeffrey M. Hsu. All rights reserved.
5 * Copyright (c) 2004 The DragonFly Project. All rights reserved.
7 * This code is derived from software contributed to The DragonFly Project
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
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37 * Copyright (c) 1982, 1986, 1988, 1991, 1993
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40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
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49 * may be used to endorse or promote products derived from this software
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54 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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57 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94
65 * $FreeBSD: src/sys/kern/uipc_mbuf.c,v 1.51.2.24 2003/04/15 06:59:29 silby Exp $
68 #include "opt_param.h"
69 #include "opt_mbuf_stress_test.h"
70 #include <sys/param.h>
71 #include <sys/systm.h>
73 #include <sys/malloc.h>
75 #include <sys/kernel.h>
76 #include <sys/sysctl.h>
77 #include <sys/domain.h>
78 #include <sys/objcache.h>
80 #include <sys/protosw.h>
82 #include <sys/thread.h>
84 #include <sys/globaldata.h>
86 #include <sys/spinlock2.h>
88 #include <machine/atomic.h>
89 #include <machine/limits.h>
92 #include <vm/vm_kern.h>
93 #include <vm/vm_extern.h>
96 #include <machine/cpu.h>
100 * mbuf cluster meta-data
108 * mbuf tracking for debugging purposes
112 static MALLOC_DEFINE(M_MTRACK
, "mtrack", "mtrack");
115 RB_HEAD(mbuf_rb_tree
, mbtrack
);
116 RB_PROTOTYPE2(mbuf_rb_tree
, mbtrack
, rb_node
, mbtrack_cmp
, struct mbuf
*);
119 RB_ENTRY(mbtrack
) rb_node
;
125 mbtrack_cmp(struct mbtrack
*mb1
, struct mbtrack
*mb2
)
134 RB_GENERATE2(mbuf_rb_tree
, mbtrack
, rb_node
, mbtrack_cmp
, struct mbuf
*, m
);
136 struct mbuf_rb_tree mbuf_track_root
;
137 static struct spinlock mbuf_track_spin
= SPINLOCK_INITIALIZER(mbuf_track_spin
, "mbuf_track_spin");
140 mbuftrack(struct mbuf
*m
)
144 mbt
= kmalloc(sizeof(*mbt
), M_MTRACK
, M_INTWAIT
|M_ZERO
);
145 spin_lock(&mbuf_track_spin
);
147 if (mbuf_rb_tree_RB_INSERT(&mbuf_track_root
, mbt
)) {
148 spin_unlock(&mbuf_track_spin
);
149 panic("mbuftrack: mbuf %p already being tracked", m
);
151 spin_unlock(&mbuf_track_spin
);
155 mbufuntrack(struct mbuf
*m
)
159 spin_lock(&mbuf_track_spin
);
160 mbt
= mbuf_rb_tree_RB_LOOKUP(&mbuf_track_root
, m
);
162 spin_unlock(&mbuf_track_spin
);
163 panic("mbufuntrack: mbuf %p was not tracked", m
);
165 mbuf_rb_tree_RB_REMOVE(&mbuf_track_root
, mbt
);
166 spin_unlock(&mbuf_track_spin
);
167 kfree(mbt
, M_MTRACK
);
172 mbuftrackid(struct mbuf
*m
, int trackid
)
177 spin_lock(&mbuf_track_spin
);
181 mbt
= mbuf_rb_tree_RB_LOOKUP(&mbuf_track_root
, m
);
183 spin_unlock(&mbuf_track_spin
);
184 panic("mbuftrackid: mbuf %p not tracked", m
);
186 mbt
->trackid
= trackid
;
191 spin_unlock(&mbuf_track_spin
);
195 mbuftrack_callback(struct mbtrack
*mbt
, void *arg
)
197 struct sysctl_req
*req
= arg
;
201 ksnprintf(buf
, sizeof(buf
), "mbuf %p track %d\n", mbt
->m
, mbt
->trackid
);
203 spin_unlock(&mbuf_track_spin
);
204 error
= SYSCTL_OUT(req
, buf
, strlen(buf
));
205 spin_lock(&mbuf_track_spin
);
212 mbuftrack_show(SYSCTL_HANDLER_ARGS
)
216 spin_lock(&mbuf_track_spin
);
217 error
= mbuf_rb_tree_RB_SCAN(&mbuf_track_root
, NULL
,
218 mbuftrack_callback
, req
);
219 spin_unlock(&mbuf_track_spin
);
222 SYSCTL_PROC(_kern_ipc
, OID_AUTO
, showmbufs
, CTLFLAG_RD
|CTLTYPE_STRING
,
223 0, 0, mbuftrack_show
, "A", "Show all in-use mbufs");
228 #define mbufuntrack(m)
232 static void mbinit(void *);
233 SYSINIT(mbuf
, SI_BOOT2_MACHDEP
, SI_ORDER_FIRST
, mbinit
, NULL
);
235 struct mbtypes_stat
{
236 u_long stats
[MT_NTYPES
];
239 static struct mbtypes_stat mbtypes
[SMP_MAXCPU
];
241 static struct mbstat mbstat
[SMP_MAXCPU
] __cachealign
;
250 #ifdef MBUF_STRESS_TEST
251 int m_defragrandomfailures
;
254 struct objcache
*mbuf_cache
, *mbufphdr_cache
;
255 struct objcache
*mclmeta_cache
, *mjclmeta_cache
;
256 struct objcache
*mbufcluster_cache
, *mbufphdrcluster_cache
;
257 struct objcache
*mbufjcluster_cache
, *mbufphdrjcluster_cache
;
259 struct lock mbupdate_lk
= LOCK_INITIALIZER("mbupdate", 0, LK_CANRECURSE
);
262 static int nmbjclusters
;
265 static int mjclph_cachefrac
;
266 static int mjcl_cachefrac
;
267 static int mclph_cachefrac
;
268 static int mcl_cachefrac
;
270 SYSCTL_INT(_kern_ipc
, KIPC_MAX_LINKHDR
, max_linkhdr
, CTLFLAG_RW
,
271 &max_linkhdr
, 0, "Max size of a link-level header");
272 SYSCTL_INT(_kern_ipc
, KIPC_MAX_PROTOHDR
, max_protohdr
, CTLFLAG_RW
,
273 &max_protohdr
, 0, "Max size of a protocol header");
274 SYSCTL_INT(_kern_ipc
, KIPC_MAX_HDR
, max_hdr
, CTLFLAG_RW
, &max_hdr
, 0,
275 "Max size of link+protocol headers");
276 SYSCTL_INT(_kern_ipc
, KIPC_MAX_DATALEN
, max_datalen
, CTLFLAG_RW
,
277 &max_datalen
, 0, "Max data payload size without headers");
278 SYSCTL_INT(_kern_ipc
, OID_AUTO
, mbuf_wait
, CTLFLAG_RW
,
279 &mbuf_wait
, 0, "Time in ticks to sleep after failed mbuf allocations");
280 static int do_mbstat(SYSCTL_HANDLER_ARGS
);
282 SYSCTL_PROC(_kern_ipc
, KIPC_MBSTAT
, mbstat
, CTLTYPE_STRUCT
|CTLFLAG_RD
,
283 0, 0, do_mbstat
, "S,mbstat", "mbuf usage statistics");
285 static int do_mbtypes(SYSCTL_HANDLER_ARGS
);
287 SYSCTL_PROC(_kern_ipc
, OID_AUTO
, mbtypes
, CTLTYPE_ULONG
|CTLFLAG_RD
,
288 0, 0, do_mbtypes
, "LU", "");
291 do_mbstat(SYSCTL_HANDLER_ARGS
)
293 struct mbstat mbstat_total
;
294 struct mbstat
*mbstat_totalp
;
297 bzero(&mbstat_total
, sizeof(mbstat_total
));
298 mbstat_totalp
= &mbstat_total
;
300 for (i
= 0; i
< ncpus
; i
++) {
301 mbstat_total
.m_mbufs
+= mbstat
[i
].m_mbufs
;
302 mbstat_total
.m_clusters
+= mbstat
[i
].m_clusters
;
303 mbstat_total
.m_jclusters
+= mbstat
[i
].m_jclusters
;
304 mbstat_total
.m_clfree
+= mbstat
[i
].m_clfree
;
305 mbstat_total
.m_drops
+= mbstat
[i
].m_drops
;
306 mbstat_total
.m_wait
+= mbstat
[i
].m_wait
;
307 mbstat_total
.m_drain
+= mbstat
[i
].m_drain
;
308 mbstat_total
.m_mcfail
+= mbstat
[i
].m_mcfail
;
309 mbstat_total
.m_mpfail
+= mbstat
[i
].m_mpfail
;
313 * The following fields are not cumulative fields so just
314 * get their values once.
316 mbstat_total
.m_msize
= mbstat
[0].m_msize
;
317 mbstat_total
.m_mclbytes
= mbstat
[0].m_mclbytes
;
318 mbstat_total
.m_minclsize
= mbstat
[0].m_minclsize
;
319 mbstat_total
.m_mlen
= mbstat
[0].m_mlen
;
320 mbstat_total
.m_mhlen
= mbstat
[0].m_mhlen
;
322 return(sysctl_handle_opaque(oidp
, mbstat_totalp
, sizeof(mbstat_total
), req
));
326 do_mbtypes(SYSCTL_HANDLER_ARGS
)
328 u_long totals
[MT_NTYPES
];
331 for (i
= 0; i
< MT_NTYPES
; i
++)
334 for (i
= 0; i
< ncpus
; i
++) {
335 for (j
= 0; j
< MT_NTYPES
; j
++)
336 totals
[j
] += mbtypes
[i
].stats
[j
];
339 return(sysctl_handle_opaque(oidp
, totals
, sizeof(totals
), req
));
343 * The variables may be set as boot-time tunables or live. Setting these
344 * values too low can deadlock your network. Network interfaces may also
345 * adjust nmbclusters and/or nmbjclusters to account for preloading the
348 static int sysctl_nmbclusters(SYSCTL_HANDLER_ARGS
);
349 static int sysctl_nmbjclusters(SYSCTL_HANDLER_ARGS
);
350 static int sysctl_nmbufs(SYSCTL_HANDLER_ARGS
);
351 SYSCTL_PROC(_kern_ipc
, KIPC_NMBCLUSTERS
, nmbclusters
, CTLTYPE_INT
| CTLFLAG_RW
,
352 0, 0, sysctl_nmbclusters
, "I",
353 "Maximum number of mbuf clusters available");
354 SYSCTL_PROC(_kern_ipc
, OID_AUTO
, nmbjclusters
, CTLTYPE_INT
| CTLFLAG_RW
,
355 0, 0, sysctl_nmbjclusters
, "I",
356 "Maximum number of mbuf jclusters available");
357 SYSCTL_PROC(_kern_ipc
, OID_AUTO
, nmbufs
, CTLTYPE_INT
| CTLFLAG_RW
,
358 0, 0, sysctl_nmbufs
, "I",
359 "Maximum number of mbufs available");
361 SYSCTL_INT(_kern_ipc
, OID_AUTO
, mjclph_cachefrac
, CTLFLAG_RD
,
362 &mjclph_cachefrac
, 0,
363 "Fraction of cacheable mbuf jclusters w/ pkthdr");
364 SYSCTL_INT(_kern_ipc
, OID_AUTO
, mjcl_cachefrac
, CTLFLAG_RD
,
366 "Fraction of cacheable mbuf jclusters");
367 SYSCTL_INT(_kern_ipc
, OID_AUTO
, mclph_cachefrac
, CTLFLAG_RD
,
369 "Fraction of cacheable mbuf clusters w/ pkthdr");
370 SYSCTL_INT(_kern_ipc
, OID_AUTO
, mcl_cachefrac
, CTLFLAG_RD
,
371 &mcl_cachefrac
, 0, "Fraction of cacheable mbuf clusters");
373 SYSCTL_INT(_kern_ipc
, OID_AUTO
, m_defragpackets
, CTLFLAG_RD
,
374 &m_defragpackets
, 0, "Number of defragment packets");
375 SYSCTL_INT(_kern_ipc
, OID_AUTO
, m_defragbytes
, CTLFLAG_RD
,
376 &m_defragbytes
, 0, "Number of defragment bytes");
377 SYSCTL_INT(_kern_ipc
, OID_AUTO
, m_defraguseless
, CTLFLAG_RD
,
378 &m_defraguseless
, 0, "Number of useless defragment mbuf chain operations");
379 SYSCTL_INT(_kern_ipc
, OID_AUTO
, m_defragfailure
, CTLFLAG_RD
,
380 &m_defragfailure
, 0, "Number of failed defragment mbuf chain operations");
381 #ifdef MBUF_STRESS_TEST
382 SYSCTL_INT(_kern_ipc
, OID_AUTO
, m_defragrandomfailures
, CTLFLAG_RW
,
383 &m_defragrandomfailures
, 0, "");
386 static MALLOC_DEFINE(M_MBUF
, "mbuf", "mbuf");
387 static MALLOC_DEFINE(M_MBUFCL
, "mbufcl", "mbufcl");
388 static MALLOC_DEFINE(M_MCLMETA
, "mclmeta", "mclmeta");
390 static void m_reclaim (void);
391 static void m_mclref(void *arg
);
392 static void m_mclfree(void *arg
);
393 static void m_mjclfree(void *arg
);
395 static void mbupdatelimits(void);
398 * Generally scale default mbufs to maxproc.
400 * NOTE: Default NMBUFS must take into account a possible DOS attack
401 * using fd passing on unix domain sockets.
404 #define NMBCLUSTERS (512 + maxproc * 4)
406 #ifndef BASE_CACHEFRAC
407 #define BASE_CACHEFRAC 16
409 #ifndef MJCLPH_CACHEFRAC
410 #define MJCLPH_CACHEFRAC (BASE_CACHEFRAC * 2)
412 #ifndef MJCL_CACHEFRAC
413 #define MJCL_CACHEFRAC (BASE_CACHEFRAC * 2)
415 #ifndef MCLPH_CACHEFRAC
416 #define MCLPH_CACHEFRAC (BASE_CACHEFRAC * 2)
418 #ifndef MCL_CACHEFRAC
419 #define MCL_CACHEFRAC (BASE_CACHEFRAC * 2)
422 #define NMBJCLUSTERS (NMBCLUSTERS / 4)
425 #define NMBUFS (nmbclusters / 2 + maxfiles)
428 #define NMBCLUSTERS_MIN (NMBCLUSTERS / 2)
429 #define NMBJCLUSTERS_MIN (NMBJCLUSTERS / 2)
430 #define NMBUFS_MIN (NMBUFS / 2)
433 * Perform sanity checks of tunables declared above.
436 tunable_mbinit(void *dummy
)
439 * This has to be done before VM init.
441 nmbclusters
= NMBCLUSTERS
;
442 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters
);
443 mjclph_cachefrac
= MJCLPH_CACHEFRAC
;
444 TUNABLE_INT_FETCH("kern.ipc.mjclph_cachefrac", &mjclph_cachefrac
);
445 mjcl_cachefrac
= MJCL_CACHEFRAC
;
446 TUNABLE_INT_FETCH("kern.ipc.mjcl_cachefrac", &mjcl_cachefrac
);
447 mclph_cachefrac
= MCLPH_CACHEFRAC
;
448 TUNABLE_INT_FETCH("kern.ipc.mclph_cachefrac", &mclph_cachefrac
);
449 mcl_cachefrac
= MCL_CACHEFRAC
;
450 TUNABLE_INT_FETCH("kern.ipc.mcl_cachefrac", &mcl_cachefrac
);
453 * WARNING! each mcl cache feeds two mbuf caches, so the minimum
454 * cachefrac is 2. For safety, use 3.
456 if (mjclph_cachefrac
< 3)
457 mjclph_cachefrac
= 3;
458 if (mjcl_cachefrac
< 3)
460 if (mclph_cachefrac
< 3)
462 if (mcl_cachefrac
< 3)
465 nmbjclusters
= NMBJCLUSTERS
;
466 TUNABLE_INT_FETCH("kern.ipc.nmbjclusters", &nmbjclusters
);
469 TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs
);
472 if (nmbufs
< nmbclusters
* 2)
473 nmbufs
= nmbclusters
* 2;
475 SYSINIT(tunable_mbinit
, SI_BOOT1_TUNABLES
, SI_ORDER_ANY
,
476 tunable_mbinit
, NULL
);
479 mbinclimit(int *limit
, int inc
, int minlim
)
483 lockmgr(&mbupdate_lk
, LK_EXCLUSIVE
);
485 new_limit
= *limit
+ inc
;
486 if (new_limit
< minlim
)
489 if (*limit
!= new_limit
) {
494 lockmgr(&mbupdate_lk
, LK_RELEASE
);
498 mbsetlimit(int *limit
, int new_limit
, int minlim
)
500 if (new_limit
< minlim
)
503 lockmgr(&mbupdate_lk
, LK_EXCLUSIVE
);
504 mbinclimit(limit
, new_limit
- *limit
, minlim
);
505 lockmgr(&mbupdate_lk
, LK_RELEASE
);
510 sysctl_mblimit(SYSCTL_HANDLER_ARGS
, int *limit
, int minlim
)
515 error
= sysctl_handle_int(oidp
, &value
, 0, req
);
516 if (error
|| req
->newptr
== NULL
)
519 return mbsetlimit(limit
, value
, minlim
);
523 * Sysctl support to update nmbclusters, nmbjclusters, and nmbufs.
526 sysctl_nmbclusters(SYSCTL_HANDLER_ARGS
)
528 return sysctl_mblimit(oidp
, arg1
, arg2
, req
, &nmbclusters
,
533 sysctl_nmbjclusters(SYSCTL_HANDLER_ARGS
)
535 return sysctl_mblimit(oidp
, arg1
, arg2
, req
, &nmbjclusters
,
540 sysctl_nmbufs(SYSCTL_HANDLER_ARGS
)
542 return sysctl_mblimit(oidp
, arg1
, arg2
, req
, &nmbufs
, NMBUFS_MIN
);
546 mcl_inclimit(int inc
)
548 mbinclimit(&nmbclusters
, inc
, NMBCLUSTERS_MIN
);
552 mjcl_inclimit(int inc
)
554 mbinclimit(&nmbjclusters
, inc
, NMBJCLUSTERS_MIN
);
560 mbinclimit(&nmbufs
, inc
, NMBUFS_MIN
);
563 /* "number of clusters of pages" */
569 * The mbuf object cache only guarantees that m_next and m_nextpkt are
570 * NULL and that m_data points to the beginning of the data area. In
571 * particular, m_len and m_pkthdr.len are uninitialized. It is the
572 * responsibility of the caller to initialize those fields before use.
574 static __inline boolean_t
575 mbuf_ctor(void *obj
, void *private, int ocflags
)
577 struct mbuf
*m
= obj
;
581 m
->m_data
= m
->m_dat
;
588 * Initialize the mbuf and the packet header fields.
591 mbufphdr_ctor(void *obj
, void *private, int ocflags
)
593 struct mbuf
*m
= obj
;
597 m
->m_data
= m
->m_pktdat
;
598 m
->m_flags
= M_PKTHDR
| M_PHCACHE
;
600 m
->m_pkthdr
.rcvif
= NULL
; /* eliminate XXX JH */
601 SLIST_INIT(&m
->m_pkthdr
.tags
);
602 m
->m_pkthdr
.csum_flags
= 0; /* eliminate XXX JH */
603 m
->m_pkthdr
.fw_flags
= 0; /* eliminate XXX JH */
609 * A mbcluster object consists of 2K (MCLBYTES) cluster and a refcount.
612 mclmeta_ctor(void *obj
, void *private, int ocflags
)
614 struct mbcluster
*cl
= obj
;
617 if (ocflags
& M_NOWAIT
)
618 buf
= kmalloc(MCLBYTES
, M_MBUFCL
, M_NOWAIT
| M_ZERO
);
620 buf
= kmalloc(MCLBYTES
, M_MBUFCL
, M_INTWAIT
| M_ZERO
);
629 mjclmeta_ctor(void *obj
, void *private, int ocflags
)
631 struct mbcluster
*cl
= obj
;
634 if (ocflags
& M_NOWAIT
)
635 buf
= kmalloc(MJUMPAGESIZE
, M_MBUFCL
, M_NOWAIT
| M_ZERO
);
637 buf
= kmalloc(MJUMPAGESIZE
, M_MBUFCL
, M_INTWAIT
| M_ZERO
);
646 mclmeta_dtor(void *obj
, void *private)
648 struct mbcluster
*mcl
= obj
;
650 KKASSERT(mcl
->mcl_refs
== 0);
651 kfree(mcl
->mcl_data
, M_MBUFCL
);
655 linkjcluster(struct mbuf
*m
, struct mbcluster
*cl
, uint size
)
658 * Add the cluster to the mbuf. The caller will detect that the
659 * mbuf now has an attached cluster.
661 m
->m_ext
.ext_arg
= cl
;
662 m
->m_ext
.ext_buf
= cl
->mcl_data
;
663 m
->m_ext
.ext_ref
= m_mclref
;
664 if (size
!= MCLBYTES
)
665 m
->m_ext
.ext_free
= m_mjclfree
;
667 m
->m_ext
.ext_free
= m_mclfree
;
668 m
->m_ext
.ext_size
= size
;
669 atomic_add_int(&cl
->mcl_refs
, 1);
671 m
->m_data
= m
->m_ext
.ext_buf
;
672 m
->m_flags
|= M_EXT
| M_EXT_CLUSTER
;
676 linkcluster(struct mbuf
*m
, struct mbcluster
*cl
)
678 linkjcluster(m
, cl
, MCLBYTES
);
682 mbufphdrcluster_ctor(void *obj
, void *private, int ocflags
)
684 struct mbuf
*m
= obj
;
685 struct mbcluster
*cl
;
687 mbufphdr_ctor(obj
, private, ocflags
);
688 cl
= objcache_get(mclmeta_cache
, ocflags
);
690 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
693 m
->m_flags
|= M_CLCACHE
;
699 mbufphdrjcluster_ctor(void *obj
, void *private, int ocflags
)
701 struct mbuf
*m
= obj
;
702 struct mbcluster
*cl
;
704 mbufphdr_ctor(obj
, private, ocflags
);
705 cl
= objcache_get(mjclmeta_cache
, ocflags
);
707 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
710 m
->m_flags
|= M_CLCACHE
;
711 linkjcluster(m
, cl
, MJUMPAGESIZE
);
716 mbufcluster_ctor(void *obj
, void *private, int ocflags
)
718 struct mbuf
*m
= obj
;
719 struct mbcluster
*cl
;
721 mbuf_ctor(obj
, private, ocflags
);
722 cl
= objcache_get(mclmeta_cache
, ocflags
);
724 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
727 m
->m_flags
|= M_CLCACHE
;
733 mbufjcluster_ctor(void *obj
, void *private, int ocflags
)
735 struct mbuf
*m
= obj
;
736 struct mbcluster
*cl
;
738 mbuf_ctor(obj
, private, ocflags
);
739 cl
= objcache_get(mjclmeta_cache
, ocflags
);
741 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
744 m
->m_flags
|= M_CLCACHE
;
745 linkjcluster(m
, cl
, MJUMPAGESIZE
);
750 * Used for both the cluster and cluster PHDR caches.
752 * The mbuf may have lost its cluster due to sharing, deal
753 * with the situation by checking M_EXT.
756 mbufcluster_dtor(void *obj
, void *private)
758 struct mbuf
*m
= obj
;
759 struct mbcluster
*mcl
;
761 if (m
->m_flags
& M_EXT
) {
762 KKASSERT((m
->m_flags
& M_EXT_CLUSTER
) != 0);
763 mcl
= m
->m_ext
.ext_arg
;
764 KKASSERT(mcl
->mcl_refs
== 1);
766 if (m
->m_flags
& M_EXT
&& m
->m_ext
.ext_size
!= MCLBYTES
)
767 objcache_put(mjclmeta_cache
, mcl
);
769 objcache_put(mclmeta_cache
, mcl
);
773 struct objcache_malloc_args mbuf_malloc_args
= { MSIZE
, M_MBUF
};
774 struct objcache_malloc_args mclmeta_malloc_args
=
775 { sizeof(struct mbcluster
), M_MCLMETA
};
781 int mb_limit
, cl_limit
, ncl_limit
, jcl_limit
;
786 * Initialize statistics
788 for (i
= 0; i
< ncpus
; i
++) {
789 mbstat
[i
].m_msize
= MSIZE
;
790 mbstat
[i
].m_mclbytes
= MCLBYTES
;
791 mbstat
[i
].m_mjumpagesize
= MJUMPAGESIZE
;
792 mbstat
[i
].m_minclsize
= MINCLSIZE
;
793 mbstat
[i
].m_mlen
= MLEN
;
794 mbstat
[i
].m_mhlen
= MHLEN
;
798 * Create object caches and save cluster limits, which will
799 * be used to adjust backing kmalloc pools' limit later.
802 mb_limit
= cl_limit
= 0;
805 mbuf_cache
= objcache_create("mbuf",
806 limit
, nmbufs
/ BASE_CACHEFRAC
,
807 mbuf_ctor
, NULL
, NULL
,
808 objcache_malloc_alloc
, objcache_malloc_free
, &mbuf_malloc_args
);
812 mbufphdr_cache
= objcache_create("mbuf pkthdr",
813 limit
, nmbufs
/ BASE_CACHEFRAC
,
814 mbufphdr_ctor
, NULL
, NULL
,
815 objcache_malloc_alloc
, objcache_malloc_free
, &mbuf_malloc_args
);
818 ncl_limit
= nmbclusters
;
819 mclmeta_cache
= objcache_create("mbuf cluster",
820 ncl_limit
, nmbclusters
/ BASE_CACHEFRAC
,
821 mclmeta_ctor
, mclmeta_dtor
, NULL
,
822 objcache_malloc_alloc
, objcache_malloc_free
, &mclmeta_malloc_args
);
823 cl_limit
+= ncl_limit
;
825 jcl_limit
= nmbjclusters
;
826 mjclmeta_cache
= objcache_create("mbuf jcluster",
827 jcl_limit
, nmbjclusters
/ BASE_CACHEFRAC
,
828 mjclmeta_ctor
, mclmeta_dtor
, NULL
,
829 objcache_malloc_alloc
, objcache_malloc_free
, &mclmeta_malloc_args
);
830 cl_limit
+= jcl_limit
;
833 mbufcluster_cache
= objcache_create("mbuf+cl",
834 limit
, nmbclusters
/ mcl_cachefrac
,
835 mbufcluster_ctor
, mbufcluster_dtor
, NULL
,
836 objcache_malloc_alloc
, objcache_malloc_free
, &mbuf_malloc_args
);
840 mbufphdrcluster_cache
= objcache_create("mbuf pkthdr+cl",
841 limit
, nmbclusters
/ mclph_cachefrac
,
842 mbufphdrcluster_ctor
, mbufcluster_dtor
, NULL
,
843 objcache_malloc_alloc
, objcache_malloc_free
, &mbuf_malloc_args
);
846 limit
= nmbjclusters
;
847 mbufjcluster_cache
= objcache_create("mbuf+jcl",
848 limit
, nmbjclusters
/ mjcl_cachefrac
,
849 mbufjcluster_ctor
, mbufcluster_dtor
, NULL
,
850 objcache_malloc_alloc
, objcache_malloc_free
, &mbuf_malloc_args
);
853 limit
= nmbjclusters
;
854 mbufphdrjcluster_cache
= objcache_create("mbuf pkthdr+jcl",
855 limit
, nmbjclusters
/ mjclph_cachefrac
,
856 mbufphdrjcluster_ctor
, mbufcluster_dtor
, NULL
,
857 objcache_malloc_alloc
, objcache_malloc_free
, &mbuf_malloc_args
);
861 * Adjust backing kmalloc pools' limit
863 * NOTE: We raise the limit by another 1/8 to take the effect
864 * of loosememuse into account.
866 cl_limit
+= cl_limit
/ 8;
867 kmalloc_raise_limit(mclmeta_malloc_args
.mtype
,
868 mclmeta_malloc_args
.objsize
* (size_t)cl_limit
);
869 kmalloc_raise_limit(M_MBUFCL
,
870 (MCLBYTES
* (size_t)ncl_limit
) +
871 (MJUMPAGESIZE
* (size_t)jcl_limit
));
873 mb_limit
+= mb_limit
/ 8;
874 kmalloc_raise_limit(mbuf_malloc_args
.mtype
,
875 mbuf_malloc_args
.objsize
* (size_t)mb_limit
);
879 * Adjust mbuf limits after changes have been made
881 * Caller must hold mbupdate_lk
886 int mb_limit
, cl_limit
, ncl_limit
, jcl_limit
;
889 KASSERT(lockstatus(&mbupdate_lk
, curthread
) != 0,
890 ("mbupdate_lk is not held"));
893 * Figure out adjustments to object caches after nmbufs, nmbclusters,
894 * or nmbjclusters has been modified.
896 mb_limit
= cl_limit
= 0;
899 objcache_set_cluster_limit(mbuf_cache
, limit
);
903 objcache_set_cluster_limit(mbufphdr_cache
, limit
);
906 ncl_limit
= nmbclusters
;
907 objcache_set_cluster_limit(mclmeta_cache
, ncl_limit
);
908 cl_limit
+= ncl_limit
;
910 jcl_limit
= nmbjclusters
;
911 objcache_set_cluster_limit(mjclmeta_cache
, jcl_limit
);
912 cl_limit
+= jcl_limit
;
915 objcache_set_cluster_limit(mbufcluster_cache
, limit
);
919 objcache_set_cluster_limit(mbufphdrcluster_cache
, limit
);
922 limit
= nmbjclusters
;
923 objcache_set_cluster_limit(mbufjcluster_cache
, limit
);
926 limit
= nmbjclusters
;
927 objcache_set_cluster_limit(mbufphdrjcluster_cache
, limit
);
931 * Adjust backing kmalloc pools' limit
933 * NOTE: We raise the limit by another 1/8 to take the effect
934 * of loosememuse into account.
936 cl_limit
+= cl_limit
/ 8;
937 kmalloc_raise_limit(mclmeta_malloc_args
.mtype
,
938 mclmeta_malloc_args
.objsize
* (size_t)cl_limit
);
939 kmalloc_raise_limit(M_MBUFCL
,
940 (MCLBYTES
* (size_t)ncl_limit
) +
941 (MJUMPAGESIZE
* (size_t)jcl_limit
));
942 mb_limit
+= mb_limit
/ 8;
943 kmalloc_raise_limit(mbuf_malloc_args
.mtype
,
944 mbuf_malloc_args
.objsize
* (size_t)mb_limit
);
948 * Return the number of references to this mbuf's data. 0 is returned
949 * if the mbuf is not M_EXT, a reference count is returned if it is
950 * M_EXT | M_EXT_CLUSTER, and 99 is returned if it is a special M_EXT.
953 m_sharecount(struct mbuf
*m
)
955 switch (m
->m_flags
& (M_EXT
| M_EXT_CLUSTER
)) {
960 case M_EXT
| M_EXT_CLUSTER
:
961 return (((struct mbcluster
*)m
->m_ext
.ext_arg
)->mcl_refs
);
964 return (0); /* to shut up compiler */
968 * change mbuf to new type
971 m_chtype(struct mbuf
*m
, int type
)
973 struct globaldata
*gd
= mycpu
;
975 ++mbtypes
[gd
->gd_cpuid
].stats
[type
];
976 --mbtypes
[gd
->gd_cpuid
].stats
[m
->m_type
];
986 kprintf("Debug: m_reclaim() called\n");
988 SLIST_FOREACH(dp
, &domains
, dom_next
) {
989 for (pr
= dp
->dom_protosw
; pr
< dp
->dom_protoswNPROTOSW
; pr
++) {
994 ++mbstat
[mycpu
->gd_cpuid
].m_drain
;
998 updatestats(struct mbuf
*m
, int type
)
1000 struct globaldata
*gd
= mycpu
;
1005 KASSERT(m
->m_next
== NULL
, ("mbuf %p: bad m_next in get", m
));
1006 KASSERT(m
->m_nextpkt
== NULL
, ("mbuf %p: bad m_nextpkt in get", m
));
1009 ++mbtypes
[gd
->gd_cpuid
].stats
[type
];
1010 ++mbstat
[gd
->gd_cpuid
].m_mbufs
;
1018 m_get(int how
, int type
)
1022 int ocf
= MB_OCFLAG(how
);
1026 m
= objcache_get(mbuf_cache
, ocf
);
1029 if ((ocf
& M_WAITOK
) && ntries
++ == 0) {
1030 struct objcache
*reclaimlist
[] = {
1033 mbufphdrcluster_cache
,
1035 mbufphdrjcluster_cache
1037 const int nreclaims
= NELEM(reclaimlist
);
1039 if (!objcache_reclaimlist(reclaimlist
, nreclaims
, ocf
))
1043 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
1047 KASSERT(m
->m_data
== m
->m_dat
, ("mbuf %p: bad m_data in get", m
));
1051 updatestats(m
, type
);
1056 m_gethdr(int how
, int type
)
1059 int ocf
= MB_OCFLAG(how
);
1064 m
= objcache_get(mbufphdr_cache
, ocf
);
1067 if ((ocf
& M_WAITOK
) && ntries
++ == 0) {
1068 struct objcache
*reclaimlist
[] = {
1070 mbufcluster_cache
, mbufphdrcluster_cache
,
1071 mbufjcluster_cache
, mbufphdrjcluster_cache
1073 const int nreclaims
= NELEM(reclaimlist
);
1075 if (!objcache_reclaimlist(reclaimlist
, nreclaims
, ocf
))
1079 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
1083 KASSERT(m
->m_data
== m
->m_pktdat
, ("mbuf %p: bad m_data in get", m
));
1086 m
->m_pkthdr
.len
= 0;
1088 updatestats(m
, type
);
1093 * Get a mbuf (not a mbuf cluster!) and zero it.
1097 m_getclr(int how
, int type
)
1101 m
= m_get(how
, type
);
1103 bzero(m
->m_data
, MLEN
);
1107 static struct mbuf
*
1108 m_getcl_cache(int how
, short type
, int flags
, struct objcache
*mbclc
,
1109 struct objcache
*mbphclc
, u_long
*cl_stats
)
1111 struct mbuf
*m
= NULL
;
1112 int ocflags
= MB_OCFLAG(how
);
1117 if (flags
& M_PKTHDR
)
1118 m
= objcache_get(mbphclc
, ocflags
);
1120 m
= objcache_get(mbclc
, ocflags
);
1123 if ((ocflags
& M_WAITOK
) && ntries
++ == 0) {
1124 struct objcache
*reclaimlist
[1];
1126 if (flags
& M_PKTHDR
)
1127 reclaimlist
[0] = mbclc
;
1129 reclaimlist
[0] = mbphclc
;
1130 if (!objcache_reclaimlist(reclaimlist
, 1, ocflags
))
1134 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
1139 KASSERT(m
->m_data
== m
->m_ext
.ext_buf
,
1140 ("mbuf %p: bad m_data in get", m
));
1144 m
->m_pkthdr
.len
= 0; /* just do it unconditonally */
1148 ++mbtypes
[mycpu
->gd_cpuid
].stats
[type
];
1154 m_getjcl(int how
, short type
, int flags
, size_t size
)
1156 struct objcache
*mbclc
, *mbphclc
;
1161 mbclc
= mbufcluster_cache
;
1162 mbphclc
= mbufphdrcluster_cache
;
1163 cl_stats
= &mbstat
[mycpu
->gd_cpuid
].m_clusters
;
1167 mbclc
= mbufjcluster_cache
;
1168 mbphclc
= mbufphdrjcluster_cache
;
1169 cl_stats
= &mbstat
[mycpu
->gd_cpuid
].m_jclusters
;
1172 return m_getcl_cache(how
, type
, flags
, mbclc
, mbphclc
, cl_stats
);
1176 * Returns an mbuf with an attached cluster.
1177 * Because many network drivers use this kind of buffers a lot, it is
1178 * convenient to keep a small pool of free buffers of this kind.
1179 * Even a small size such as 10 gives about 10% improvement in the
1180 * forwarding rate in a bridge or router.
1183 m_getcl(int how
, short type
, int flags
)
1185 return m_getcl_cache(how
, type
, flags
,
1186 mbufcluster_cache
, mbufphdrcluster_cache
,
1187 &mbstat
[mycpu
->gd_cpuid
].m_clusters
);
1191 * Allocate chain of requested length.
1194 m_getc(int len
, int how
, int type
)
1196 struct mbuf
*n
, *nfirst
= NULL
, **ntail
= &nfirst
;
1200 n
= m_getl(len
, how
, type
, 0, &nsize
);
1216 * Allocate len-worth of mbufs and/or mbuf clusters (whatever fits best)
1217 * and return a pointer to the head of the allocated chain. If m0 is
1218 * non-null, then we assume that it is a single mbuf or an mbuf chain to
1219 * which we want len bytes worth of mbufs and/or clusters attached, and so
1220 * if we succeed in allocating it, we will just return a pointer to m0.
1222 * If we happen to fail at any point during the allocation, we will free
1223 * up everything we have already allocated and return NULL.
1225 * Deprecated. Use m_getc() and m_cat() instead.
1228 m_getm(struct mbuf
*m0
, int len
, int type
, int how
)
1230 struct mbuf
*nfirst
;
1232 nfirst
= m_getc(len
, how
, type
);
1235 m_last(m0
)->m_next
= nfirst
;
1243 * Adds a cluster to a normal mbuf, M_EXT is set on success.
1244 * Deprecated. Use m_getcl() instead.
1247 m_mclget(struct mbuf
*m
, int how
)
1249 struct mbcluster
*mcl
;
1251 KKASSERT((m
->m_flags
& M_EXT
) == 0);
1252 mcl
= objcache_get(mclmeta_cache
, MB_OCFLAG(how
));
1254 linkcluster(m
, mcl
);
1255 ++mbstat
[mycpu
->gd_cpuid
].m_clusters
;
1257 ++mbstat
[mycpu
->gd_cpuid
].m_drops
;
1262 * Updates to mbcluster must be MPSAFE. Only an entity which already has
1263 * a reference to the cluster can ref it, so we are in no danger of
1264 * racing an add with a subtract. But the operation must still be atomic
1265 * since multiple entities may have a reference on the cluster.
1267 * m_mclfree() is almost the same but it must contend with two entities
1268 * freeing the cluster at the same time.
1273 struct mbcluster
*mcl
= arg
;
1275 atomic_add_int(&mcl
->mcl_refs
, 1);
1279 * When dereferencing a cluster we have to deal with a N->0 race, where
1280 * N entities free their references simultaniously. To do this we use
1281 * atomic_fetchadd_int().
1284 m_mclfree(void *arg
)
1286 struct mbcluster
*mcl
= arg
;
1288 if (atomic_fetchadd_int(&mcl
->mcl_refs
, -1) == 1) {
1289 --mbstat
[mycpu
->gd_cpuid
].m_clusters
;
1290 objcache_put(mclmeta_cache
, mcl
);
1295 m_mjclfree(void *arg
)
1297 struct mbcluster
*mcl
= arg
;
1299 if (atomic_fetchadd_int(&mcl
->mcl_refs
, -1) == 1) {
1300 --mbstat
[mycpu
->gd_cpuid
].m_jclusters
;
1301 objcache_put(mjclmeta_cache
, mcl
);
1306 * Free a single mbuf and any associated external storage. The successor,
1307 * if any, is returned.
1309 * We do need to check non-first mbuf for m_aux, since some of existing
1310 * code does not call M_PREPEND properly.
1311 * (example: call to bpf_mtap from drivers)
1317 _m_free(struct mbuf
*m
, const char *func
)
1322 m_free(struct mbuf
*m
)
1327 struct globaldata
*gd
= mycpu
;
1329 KASSERT(m
->m_type
!= MT_FREE
, ("freeing free mbuf %p", m
));
1330 KASSERT(M_TRAILINGSPACE(m
) >= 0, ("overflowed mbuf %p", m
));
1331 --mbtypes
[gd
->gd_cpuid
].stats
[m
->m_type
];
1336 * Make sure the mbuf is in constructed state before returning it
1342 m
->m_hdr
.mh_lastfunc
= func
;
1345 KKASSERT(m
->m_nextpkt
== NULL
);
1347 if (m
->m_nextpkt
!= NULL
) {
1348 static int afewtimes
= 10;
1350 if (afewtimes
-- > 0) {
1351 kprintf("mfree: m->m_nextpkt != NULL\n");
1352 print_backtrace(-1);
1354 m
->m_nextpkt
= NULL
;
1357 if (m
->m_flags
& M_PKTHDR
) {
1358 m_tag_delete_chain(m
); /* eliminate XXX JH */
1361 m
->m_flags
&= (M_EXT
| M_EXT_CLUSTER
| M_CLCACHE
| M_PHCACHE
);
1364 * Clean the M_PKTHDR state so we can return the mbuf to its original
1365 * cache. This is based on the PHCACHE flag which tells us whether
1366 * the mbuf was originally allocated out of a packet-header cache
1367 * or a non-packet-header cache.
1369 if (m
->m_flags
& M_PHCACHE
) {
1370 m
->m_flags
|= M_PKTHDR
;
1371 m
->m_pkthdr
.rcvif
= NULL
; /* eliminate XXX JH */
1372 m
->m_pkthdr
.csum_flags
= 0; /* eliminate XXX JH */
1373 m
->m_pkthdr
.fw_flags
= 0; /* eliminate XXX JH */
1374 SLIST_INIT(&m
->m_pkthdr
.tags
);
1378 * Handle remaining flags combinations. M_CLCACHE tells us whether
1379 * the mbuf was originally allocated from a cluster cache or not,
1380 * and is totally separate from whether the mbuf is currently
1381 * associated with a cluster.
1383 switch(m
->m_flags
& (M_CLCACHE
| M_EXT
| M_EXT_CLUSTER
)) {
1384 case M_CLCACHE
| M_EXT
| M_EXT_CLUSTER
:
1386 * mbuf+cluster cache case. The mbuf was allocated from the
1387 * combined mbuf_cluster cache and can be returned to the
1388 * cache if the cluster hasn't been shared.
1390 if (m_sharecount(m
) == 1) {
1392 * The cluster has not been shared, we can just
1393 * reset the data pointer and return the mbuf
1394 * to the cluster cache. Note that the reference
1395 * count is left intact (it is still associated with
1398 m
->m_data
= m
->m_ext
.ext_buf
;
1399 if (m
->m_flags
& M_EXT
&& m
->m_ext
.ext_size
!= MCLBYTES
) {
1400 if (m
->m_flags
& M_PHCACHE
)
1401 objcache_put(mbufphdrjcluster_cache
, m
);
1403 objcache_put(mbufjcluster_cache
, m
);
1404 --mbstat
[mycpu
->gd_cpuid
].m_jclusters
;
1406 if (m
->m_flags
& M_PHCACHE
)
1407 objcache_put(mbufphdrcluster_cache
, m
);
1409 objcache_put(mbufcluster_cache
, m
);
1410 --mbstat
[mycpu
->gd_cpuid
].m_clusters
;
1414 * Hell. Someone else has a ref on this cluster,
1415 * we have to disconnect it which means we can't
1416 * put it back into the mbufcluster_cache, we
1417 * have to destroy the mbuf.
1419 * Other mbuf references to the cluster will typically
1420 * be M_EXT | M_EXT_CLUSTER but without M_CLCACHE.
1422 * XXX we could try to connect another cluster to
1425 m
->m_ext
.ext_free(m
->m_ext
.ext_arg
);
1426 m
->m_flags
&= ~(M_EXT
| M_EXT_CLUSTER
);
1427 if (m
->m_ext
.ext_size
== MCLBYTES
) {
1428 if (m
->m_flags
& M_PHCACHE
)
1429 objcache_dtor(mbufphdrcluster_cache
, m
);
1431 objcache_dtor(mbufcluster_cache
, m
);
1433 if (m
->m_flags
& M_PHCACHE
)
1434 objcache_dtor(mbufphdrjcluster_cache
, m
);
1436 objcache_dtor(mbufjcluster_cache
, m
);
1440 case M_EXT
| M_EXT_CLUSTER
:
1443 * Normal cluster association case, disconnect the cluster from
1444 * the mbuf. The cluster may or may not be custom.
1446 m
->m_ext
.ext_free(m
->m_ext
.ext_arg
);
1447 m
->m_flags
&= ~(M_EXT
| M_EXT_CLUSTER
);
1451 * return the mbuf to the mbuf cache.
1453 if (m
->m_flags
& M_PHCACHE
) {
1454 m
->m_data
= m
->m_pktdat
;
1455 objcache_put(mbufphdr_cache
, m
);
1457 m
->m_data
= m
->m_dat
;
1458 objcache_put(mbuf_cache
, m
);
1460 --mbstat
[mycpu
->gd_cpuid
].m_mbufs
;
1464 panic("bad mbuf flags %p %08x", m
, m
->m_flags
);
1473 _m_freem(struct mbuf
*m
, const char *func
)
1476 m
= _m_free(m
, func
);
1482 m_freem(struct mbuf
*m
)
1491 m_extadd(struct mbuf
*m
, caddr_t buf
, u_int size
, void (*reff
)(void *),
1492 void (*freef
)(void *), void *arg
)
1494 m
->m_ext
.ext_arg
= arg
;
1495 m
->m_ext
.ext_buf
= buf
;
1496 m
->m_ext
.ext_ref
= reff
;
1497 m
->m_ext
.ext_free
= freef
;
1498 m
->m_ext
.ext_size
= size
;
1501 m
->m_flags
|= M_EXT
;
1505 * mbuf utility routines
1509 * Lesser-used path for M_PREPEND: allocate new mbuf to prepend to chain and
1513 m_prepend(struct mbuf
*m
, int len
, int how
)
1517 if (m
->m_flags
& M_PKTHDR
)
1518 mn
= m_gethdr(how
, m
->m_type
);
1520 mn
= m_get(how
, m
->m_type
);
1525 if (m
->m_flags
& M_PKTHDR
)
1526 M_MOVE_PKTHDR(mn
, m
);
1536 * Make a copy of an mbuf chain starting "off0" bytes from the beginning,
1537 * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf.
1538 * The wait parameter is a choice of M_WAITOK/M_NOWAIT from caller.
1539 * Note that the copy is read-only, because clusters are not copied,
1540 * only their reference counts are incremented.
1543 m_copym(const struct mbuf
*m
, int off0
, int len
, int wait
)
1545 struct mbuf
*n
, **np
;
1550 KASSERT(off
>= 0, ("m_copym, negative off %d", off
));
1551 KASSERT(len
>= 0, ("m_copym, negative len %d", len
));
1552 if (off
== 0 && (m
->m_flags
& M_PKTHDR
))
1555 KASSERT(m
!= NULL
, ("m_copym, offset > size of mbuf chain"));
1565 KASSERT(len
== M_COPYALL
,
1566 ("m_copym, length > size of mbuf chain"));
1570 * Because we are sharing any cluster attachment below,
1571 * be sure to get an mbuf that does not have a cluster
1572 * associated with it.
1575 n
= m_gethdr(wait
, m
->m_type
);
1577 n
= m_get(wait
, m
->m_type
);
1582 if (!m_dup_pkthdr(n
, m
, wait
))
1584 if (len
== M_COPYALL
)
1585 n
->m_pkthdr
.len
-= off0
;
1587 n
->m_pkthdr
.len
= len
;
1590 n
->m_len
= min(len
, m
->m_len
- off
);
1591 if (m
->m_flags
& M_EXT
) {
1592 KKASSERT((n
->m_flags
& M_EXT
) == 0);
1593 n
->m_data
= m
->m_data
+ off
;
1594 m
->m_ext
.ext_ref(m
->m_ext
.ext_arg
);
1595 n
->m_ext
= m
->m_ext
;
1596 n
->m_flags
|= m
->m_flags
& (M_EXT
| M_EXT_CLUSTER
);
1598 bcopy(mtod(m
, caddr_t
)+off
, mtod(n
, caddr_t
),
1599 (unsigned)n
->m_len
);
1601 if (len
!= M_COPYALL
)
1608 ++mbstat
[mycpu
->gd_cpuid
].m_mcfail
;
1612 ++mbstat
[mycpu
->gd_cpuid
].m_mcfail
;
1617 * Copy an entire packet, including header (which must be present).
1618 * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'.
1619 * Note that the copy is read-only, because clusters are not copied,
1620 * only their reference counts are incremented.
1621 * Preserve alignment of the first mbuf so if the creator has left
1622 * some room at the beginning (e.g. for inserting protocol headers)
1623 * the copies also have the room available.
1626 m_copypacket(struct mbuf
*m
, int how
)
1628 struct mbuf
*top
, *n
, *o
;
1630 n
= m_gethdr(how
, m
->m_type
);
1635 if (!m_dup_pkthdr(n
, m
, how
))
1637 n
->m_len
= m
->m_len
;
1638 if (m
->m_flags
& M_EXT
) {
1639 KKASSERT((n
->m_flags
& M_EXT
) == 0);
1640 n
->m_data
= m
->m_data
;
1641 m
->m_ext
.ext_ref(m
->m_ext
.ext_arg
);
1642 n
->m_ext
= m
->m_ext
;
1643 n
->m_flags
|= m
->m_flags
& (M_EXT
| M_EXT_CLUSTER
);
1645 n
->m_data
= n
->m_pktdat
+ (m
->m_data
- m
->m_pktdat
);
1646 bcopy(mtod(m
, char *), mtod(n
, char *), n
->m_len
);
1651 o
= m_get(how
, m
->m_type
);
1658 n
->m_len
= m
->m_len
;
1659 if (m
->m_flags
& M_EXT
) {
1660 KKASSERT((n
->m_flags
& M_EXT
) == 0);
1661 n
->m_data
= m
->m_data
;
1662 m
->m_ext
.ext_ref(m
->m_ext
.ext_arg
);
1663 n
->m_ext
= m
->m_ext
;
1664 n
->m_flags
|= m
->m_flags
& (M_EXT
| M_EXT_CLUSTER
);
1666 bcopy(mtod(m
, char *), mtod(n
, char *), n
->m_len
);
1674 ++mbstat
[mycpu
->gd_cpuid
].m_mcfail
;
1679 * Copy data from an mbuf chain starting "off" bytes from the beginning,
1680 * continuing for "len" bytes, into the indicated buffer.
1683 m_copydata(const struct mbuf
*m
, int off
, int len
, caddr_t cp
)
1687 KASSERT(off
>= 0, ("m_copydata, negative off %d", off
));
1688 KASSERT(len
>= 0, ("m_copydata, negative len %d", len
));
1690 KASSERT(m
!= NULL
, ("m_copydata, offset > size of mbuf chain"));
1697 KASSERT(m
!= NULL
, ("m_copydata, length > size of mbuf chain"));
1698 count
= min(m
->m_len
- off
, len
);
1699 bcopy(mtod(m
, caddr_t
) + off
, cp
, count
);
1708 * Copy a packet header mbuf chain into a completely new chain, including
1709 * copying any mbuf clusters. Use this instead of m_copypacket() when
1710 * you need a writable copy of an mbuf chain.
1713 m_dup(struct mbuf
*m
, int how
)
1715 struct mbuf
**p
, *top
= NULL
;
1716 int remain
, moff
, nsize
;
1721 KASSERT((m
->m_flags
& M_PKTHDR
) != 0, ("%s: !PKTHDR", __func__
));
1723 /* While there's more data, get a new mbuf, tack it on, and fill it */
1724 remain
= m
->m_pkthdr
.len
;
1727 while (remain
> 0 || top
== NULL
) { /* allow m->m_pkthdr.len == 0 */
1730 /* Get the next new mbuf */
1731 n
= m_getl(remain
, how
, m
->m_type
, top
== NULL
? M_PKTHDR
: 0,
1736 if (!m_dup_pkthdr(n
, m
, how
))
1739 /* Link it into the new chain */
1743 /* Copy data from original mbuf(s) into new mbuf */
1745 while (n
->m_len
< nsize
&& m
!= NULL
) {
1746 int chunk
= min(nsize
- n
->m_len
, m
->m_len
- moff
);
1748 bcopy(m
->m_data
+ moff
, n
->m_data
+ n
->m_len
, chunk
);
1752 if (moff
== m
->m_len
) {
1758 /* Check correct total mbuf length */
1759 KASSERT((remain
> 0 && m
!= NULL
) || (remain
== 0 && m
== NULL
),
1760 ("%s: bogus m_pkthdr.len", __func__
));
1767 ++mbstat
[mycpu
->gd_cpuid
].m_mcfail
;
1772 * Copy the non-packet mbuf data chain into a new set of mbufs, including
1773 * copying any mbuf clusters. This is typically used to realign a data
1774 * chain by nfs_realign().
1776 * The original chain is left intact. how should be M_WAITOK or M_NOWAIT
1777 * and NULL can be returned if M_NOWAIT is passed.
1779 * Be careful to use cluster mbufs, a large mbuf chain converted to non
1780 * cluster mbufs can exhaust our supply of mbufs.
1783 m_dup_data(struct mbuf
*m
, int how
)
1785 struct mbuf
**p
, *n
, *top
= NULL
;
1786 int mlen
, moff
, chunk
, gsize
, nsize
;
1795 * Optimize the mbuf allocation but do not get too carried away.
1797 if (m
->m_next
|| m
->m_len
> MLEN
)
1798 if (m
->m_flags
& M_EXT
&& m
->m_ext
.ext_size
== MCLBYTES
)
1801 gsize
= MJUMPAGESIZE
;
1811 * Scan the mbuf chain until nothing is left, the new mbuf chain
1812 * will be allocated on the fly as needed.
1819 KKASSERT(m
->m_type
== MT_DATA
);
1821 n
= m_getl(gsize
, how
, MT_DATA
, 0, &nsize
);
1828 chunk
= imin(mlen
, nsize
);
1829 bcopy(m
->m_data
+ moff
, n
->m_data
+ n
->m_len
, chunk
);
1844 ++mbstat
[mycpu
->gd_cpuid
].m_mcfail
;
1849 * Concatenate mbuf chain n to m.
1850 * Both chains must be of the same type (e.g. MT_DATA).
1851 * Any m_pkthdr is not updated.
1854 m_cat(struct mbuf
*m
, struct mbuf
*n
)
1858 if (m
->m_flags
& M_EXT
||
1859 m
->m_data
+ m
->m_len
+ n
->m_len
>= &m
->m_dat
[MLEN
]) {
1860 /* just join the two chains */
1864 /* splat the data from one into the other */
1865 bcopy(mtod(n
, caddr_t
), mtod(m
, caddr_t
) + m
->m_len
,
1867 m
->m_len
+= n
->m_len
;
1873 m_adj(struct mbuf
*mp
, int req_len
)
1879 if ((m
= mp
) == NULL
)
1885 while (m
!= NULL
&& len
> 0) {
1886 if (m
->m_len
<= len
) {
1897 if (mp
->m_flags
& M_PKTHDR
)
1898 m
->m_pkthdr
.len
-= (req_len
- len
);
1901 * Trim from tail. Scan the mbuf chain,
1902 * calculating its length and finding the last mbuf.
1903 * If the adjustment only affects this mbuf, then just
1904 * adjust and return. Otherwise, rescan and truncate
1905 * after the remaining size.
1911 if (m
->m_next
== NULL
)
1915 if (m
->m_len
>= len
) {
1917 if (mp
->m_flags
& M_PKTHDR
)
1918 mp
->m_pkthdr
.len
-= len
;
1925 * Correct length for chain is "count".
1926 * Find the mbuf with last data, adjust its length,
1927 * and toss data from remaining mbufs on chain.
1930 if (m
->m_flags
& M_PKTHDR
)
1931 m
->m_pkthdr
.len
= count
;
1932 for (; m
; m
= m
->m_next
) {
1933 if (m
->m_len
>= count
) {
1940 (m
= m
->m_next
) ->m_len
= 0;
1945 * Set the m_data pointer of a newly-allocated mbuf
1946 * to place an object of the specified size at the
1947 * end of the mbuf, longword aligned.
1950 m_align(struct mbuf
*m
, int len
)
1954 if (m
->m_flags
& M_EXT
)
1955 adjust
= m
->m_ext
.ext_size
- len
;
1956 else if (m
->m_flags
& M_PKTHDR
)
1957 adjust
= MHLEN
- len
;
1959 adjust
= MLEN
- len
;
1960 m
->m_data
+= rounddown2(adjust
, sizeof(long));
1964 * Create a writable copy of the mbuf chain. While doing this
1965 * we compact the chain with a goal of producing a chain with
1966 * at most two mbufs. The second mbuf in this chain is likely
1967 * to be a cluster. The primary purpose of this work is to create
1968 * a writable packet for encryption, compression, etc. The
1969 * secondary goal is to linearize the data so the data can be
1970 * passed to crypto hardware in the most efficient manner possible.
1973 m_unshare(struct mbuf
*m0
, int how
)
1975 struct mbuf
*m
, *mprev
;
1976 struct mbuf
*n
, *mfirst
, *mlast
;
1980 for (m
= m0
; m
!= NULL
; m
= mprev
->m_next
) {
1982 * Regular mbufs are ignored unless there's a cluster
1983 * in front of it that we can use to coalesce. We do
1984 * the latter mainly so later clusters can be coalesced
1985 * also w/o having to handle them specially (i.e. convert
1986 * mbuf+cluster -> cluster). This optimization is heavily
1987 * influenced by the assumption that we're running over
1988 * Ethernet where MCLBYTES is large enough that the max
1989 * packet size will permit lots of coalescing into a
1990 * single cluster. This in turn permits efficient
1991 * crypto operations, especially when using hardware.
1993 if ((m
->m_flags
& M_EXT
) == 0) {
1994 if (mprev
&& (mprev
->m_flags
& M_EXT
) &&
1995 m
->m_len
<= M_TRAILINGSPACE(mprev
)) {
1996 /* XXX: this ignores mbuf types */
1997 memcpy(mtod(mprev
, caddr_t
) + mprev
->m_len
,
1998 mtod(m
, caddr_t
), m
->m_len
);
1999 mprev
->m_len
+= m
->m_len
;
2000 mprev
->m_next
= m
->m_next
; /* unlink from chain */
2001 m_free(m
); /* reclaim mbuf */
2008 * Writable mbufs are left alone (for now).
2010 if (M_WRITABLE(m
)) {
2016 * Not writable, replace with a copy or coalesce with
2017 * the previous mbuf if possible (since we have to copy
2018 * it anyway, we try to reduce the number of mbufs and
2019 * clusters so that future work is easier).
2021 KASSERT(m
->m_flags
& M_EXT
, ("m_flags 0x%x", m
->m_flags
));
2022 /* NB: we only coalesce into a cluster or larger */
2023 if (mprev
!= NULL
&& (mprev
->m_flags
& M_EXT
) &&
2024 m
->m_len
<= M_TRAILINGSPACE(mprev
)) {
2025 /* XXX: this ignores mbuf types */
2026 memcpy(mtod(mprev
, caddr_t
) + mprev
->m_len
,
2027 mtod(m
, caddr_t
), m
->m_len
);
2028 mprev
->m_len
+= m
->m_len
;
2029 mprev
->m_next
= m
->m_next
; /* unlink from chain */
2030 m_free(m
); /* reclaim mbuf */
2035 * Allocate new space to hold the copy...
2037 /* XXX why can M_PKTHDR be set past the first mbuf? */
2038 if (mprev
== NULL
&& (m
->m_flags
& M_PKTHDR
)) {
2040 * NB: if a packet header is present we must
2041 * allocate the mbuf separately from any cluster
2042 * because M_MOVE_PKTHDR will smash the data
2043 * pointer and drop the M_EXT marker.
2045 MGETHDR(n
, how
, m
->m_type
);
2050 M_MOVE_PKTHDR(n
, m
);
2052 if ((n
->m_flags
& M_EXT
) == 0) {
2058 n
= m_getcl(how
, m
->m_type
, m
->m_flags
);
2065 * ... and copy the data. We deal with jumbo mbufs
2066 * (i.e. m_len > MCLBYTES) by splitting them into
2067 * clusters. We could just malloc a buffer and make
2068 * it external but too many device drivers don't know
2069 * how to break up the non-contiguous memory when
2077 int cc
= min(len
, MCLBYTES
);
2078 memcpy(mtod(n
, caddr_t
), mtod(m
, caddr_t
) + off
, cc
);
2089 n
= m_getcl(how
, m
->m_type
, m
->m_flags
);
2096 n
->m_next
= m
->m_next
;
2098 m0
= mfirst
; /* new head of chain */
2100 mprev
->m_next
= mfirst
; /* replace old mbuf */
2101 m_free(m
); /* release old mbuf */
2108 * Rearrange an mbuf chain so that len bytes are contiguous
2109 * and in the data area of an mbuf (so that mtod will work for a structure
2110 * of size len). Returns the resulting mbuf chain on success, frees it and
2111 * returns null on failure. If there is room, it will add up to
2112 * max_protohdr-len extra bytes to the contiguous region in an attempt to
2113 * avoid being called next time.
2116 m_pullup(struct mbuf
*n
, int len
)
2123 * If first mbuf has no cluster, and has room for len bytes
2124 * without shifting current data, pullup into it,
2125 * otherwise allocate a new mbuf to prepend to the chain.
2127 if (!(n
->m_flags
& M_EXT
) &&
2128 n
->m_data
+ len
< &n
->m_dat
[MLEN
] &&
2130 if (n
->m_len
>= len
)
2138 if (n
->m_flags
& M_PKTHDR
)
2139 m
= m_gethdr(M_NOWAIT
, n
->m_type
);
2141 m
= m_get(M_NOWAIT
, n
->m_type
);
2145 if (n
->m_flags
& M_PKTHDR
)
2146 M_MOVE_PKTHDR(m
, n
);
2148 space
= &m
->m_dat
[MLEN
] - (m
->m_data
+ m
->m_len
);
2150 count
= min(min(max(len
, max_protohdr
), space
), n
->m_len
);
2151 bcopy(mtod(n
, caddr_t
), mtod(m
, caddr_t
) + m
->m_len
,
2161 } while (len
> 0 && n
);
2170 ++mbstat
[mycpu
->gd_cpuid
].m_mcfail
;
2175 * Partition an mbuf chain in two pieces, returning the tail --
2176 * all but the first len0 bytes. In case of failure, it returns NULL and
2177 * attempts to restore the chain to its original state.
2179 * Note that the resulting mbufs might be read-only, because the new
2180 * mbuf can end up sharing an mbuf cluster with the original mbuf if
2181 * the "breaking point" happens to lie within a cluster mbuf. Use the
2182 * M_WRITABLE() macro to check for this case.
2185 m_split(struct mbuf
*m0
, int len0
, int wait
)
2188 unsigned len
= len0
, remain
;
2190 for (m
= m0
; m
&& len
> m
->m_len
; m
= m
->m_next
)
2194 remain
= m
->m_len
- len
;
2195 if (m0
->m_flags
& M_PKTHDR
) {
2196 n
= m_gethdr(wait
, m0
->m_type
);
2199 n
->m_pkthdr
.rcvif
= m0
->m_pkthdr
.rcvif
;
2200 n
->m_pkthdr
.len
= m0
->m_pkthdr
.len
- len0
;
2201 m0
->m_pkthdr
.len
= len0
;
2202 if (m
->m_flags
& M_EXT
)
2204 if (remain
> MHLEN
) {
2205 /* m can't be the lead packet */
2207 n
->m_next
= m_split(m
, len
, wait
);
2208 if (n
->m_next
== NULL
) {
2216 MH_ALIGN(n
, remain
);
2217 } else if (remain
== 0) {
2222 n
= m_get(wait
, m
->m_type
);
2228 if (m
->m_flags
& M_EXT
) {
2229 KKASSERT((n
->m_flags
& M_EXT
) == 0);
2230 n
->m_data
= m
->m_data
+ len
;
2231 m
->m_ext
.ext_ref(m
->m_ext
.ext_arg
);
2232 n
->m_ext
= m
->m_ext
;
2233 n
->m_flags
|= m
->m_flags
& (M_EXT
| M_EXT_CLUSTER
);
2235 bcopy(mtod(m
, caddr_t
) + len
, mtod(n
, caddr_t
), remain
);
2239 n
->m_next
= m
->m_next
;
2245 * Routine to copy from device local memory into mbufs.
2246 * Note: "offset" is ill-defined and always called as 0, so ignore it.
2249 m_devget(char *buf
, int len
, int offset
, struct ifnet
*ifp
)
2251 struct mbuf
*m
, *mfirst
= NULL
, **mtail
;
2258 m
= m_getl(len
, M_NOWAIT
, MT_DATA
, flags
, &nsize
);
2263 m
->m_len
= min(len
, nsize
);
2265 if (flags
& M_PKTHDR
) {
2266 if (len
+ max_linkhdr
<= nsize
)
2267 m
->m_data
+= max_linkhdr
;
2268 m
->m_pkthdr
.rcvif
= ifp
;
2269 m
->m_pkthdr
.len
= len
;
2273 bcopy(buf
, m
->m_data
, (unsigned)m
->m_len
);
2284 * Routine to pad mbuf to the specified length 'padto'.
2287 m_devpad(struct mbuf
*m
, int padto
)
2289 struct mbuf
*last
= NULL
;
2292 if (padto
<= m
->m_pkthdr
.len
)
2295 padlen
= padto
- m
->m_pkthdr
.len
;
2297 /* if there's only the packet-header and we can pad there, use it. */
2298 if (m
->m_pkthdr
.len
== m
->m_len
&& M_TRAILINGSPACE(m
) >= padlen
) {
2302 * Walk packet chain to find last mbuf. We will either
2303 * pad there, or append a new mbuf and pad it
2305 for (last
= m
; last
->m_next
!= NULL
; last
= last
->m_next
)
2308 /* `last' now points to last in chain. */
2309 if (M_TRAILINGSPACE(last
) < padlen
) {
2312 /* Allocate new empty mbuf, pad it. Compact later. */
2313 MGET(n
, M_NOWAIT
, MT_DATA
);
2321 KKASSERT(M_TRAILINGSPACE(last
) >= padlen
);
2322 KKASSERT(M_WRITABLE(last
));
2324 /* Now zero the pad area */
2325 bzero(mtod(last
, char *) + last
->m_len
, padlen
);
2326 last
->m_len
+= padlen
;
2327 m
->m_pkthdr
.len
+= padlen
;
2332 * Copy data from a buffer back into the indicated mbuf chain,
2333 * starting "off" bytes from the beginning, extending the mbuf
2334 * chain if necessary.
2337 m_copyback(struct mbuf
*m0
, int off
, int len
, caddr_t cp
)
2340 struct mbuf
*m
= m0
, *n
;
2345 while (off
> (mlen
= m
->m_len
)) {
2348 if (m
->m_next
== NULL
) {
2349 n
= m_getclr(M_NOWAIT
, m
->m_type
);
2352 n
->m_len
= min(MLEN
, len
+ off
);
2358 mlen
= min (m
->m_len
- off
, len
);
2359 bcopy(cp
, off
+ mtod(m
, caddr_t
), (unsigned)mlen
);
2367 if (m
->m_next
== NULL
) {
2368 n
= m_get(M_NOWAIT
, m
->m_type
);
2371 n
->m_len
= min(MLEN
, len
);
2376 out
: if (((m
= m0
)->m_flags
& M_PKTHDR
) && (m
->m_pkthdr
.len
< totlen
))
2377 m
->m_pkthdr
.len
= totlen
;
2381 * Append the specified data to the indicated mbuf chain,
2382 * Extend the mbuf chain if the new data does not fit in
2385 * Return 1 if able to complete the job; otherwise 0.
2388 m_append(struct mbuf
*m0
, int len
, c_caddr_t cp
)
2391 int remainder
, space
;
2393 for (m
= m0
; m
->m_next
!= NULL
; m
= m
->m_next
)
2396 space
= M_TRAILINGSPACE(m
);
2399 * Copy into available space.
2401 if (space
> remainder
)
2403 bcopy(cp
, mtod(m
, caddr_t
) + m
->m_len
, space
);
2405 cp
+= space
, remainder
-= space
;
2407 while (remainder
> 0) {
2409 * Allocate a new mbuf; could check space
2410 * and allocate a cluster instead.
2412 n
= m_get(M_NOWAIT
, m
->m_type
);
2415 n
->m_len
= min(MLEN
, remainder
);
2416 bcopy(cp
, mtod(n
, caddr_t
), n
->m_len
);
2417 cp
+= n
->m_len
, remainder
-= n
->m_len
;
2421 if (m0
->m_flags
& M_PKTHDR
)
2422 m0
->m_pkthdr
.len
+= len
- remainder
;
2423 return (remainder
== 0);
2427 * Apply function f to the data in an mbuf chain starting "off" bytes from
2428 * the beginning, continuing for "len" bytes.
2431 m_apply(struct mbuf
*m
, int off
, int len
,
2432 int (*f
)(void *, void *, u_int
), void *arg
)
2437 KASSERT(off
>= 0, ("m_apply, negative off %d", off
));
2438 KASSERT(len
>= 0, ("m_apply, negative len %d", len
));
2440 KASSERT(m
!= NULL
, ("m_apply, offset > size of mbuf chain"));
2447 KASSERT(m
!= NULL
, ("m_apply, offset > size of mbuf chain"));
2448 count
= min(m
->m_len
- off
, len
);
2449 rval
= (*f
)(arg
, mtod(m
, caddr_t
) + off
, count
);
2460 * Return a pointer to mbuf/offset of location in mbuf chain.
2463 m_getptr(struct mbuf
*m
, int loc
, int *off
)
2467 /* Normal end of search. */
2468 if (m
->m_len
> loc
) {
2473 if (m
->m_next
== NULL
) {
2475 /* Point at the end of valid data. */
2488 m_print(const struct mbuf
*m
)
2491 const struct mbuf
*m2
;
2494 len
= m
->m_pkthdr
.len
;
2496 hexstr
= kmalloc(HEX_NCPYLEN(len
), M_TEMP
, M_ZERO
| M_WAITOK
);
2498 kprintf("%p %s\n", m2
, hexncpy(m2
->m_data
, m2
->m_len
, hexstr
,
2499 HEX_NCPYLEN(m2
->m_len
), "-"));
2503 kfree(hexstr
, M_TEMP
);
2508 * "Move" mbuf pkthdr from "from" to "to".
2509 * "from" must have M_PKTHDR set, and "to" must be empty.
2512 m_move_pkthdr(struct mbuf
*to
, struct mbuf
*from
)
2514 KASSERT((to
->m_flags
& M_PKTHDR
), ("m_move_pkthdr: not packet header"));
2516 to
->m_flags
|= from
->m_flags
& M_COPYFLAGS
;
2517 to
->m_pkthdr
= from
->m_pkthdr
; /* especially tags */
2518 SLIST_INIT(&from
->m_pkthdr
.tags
); /* purge tags from src */
2522 * Duplicate "from"'s mbuf pkthdr in "to".
2523 * "from" must have M_PKTHDR set, and "to" must be empty.
2524 * In particular, this does a deep copy of the packet tags.
2527 m_dup_pkthdr(struct mbuf
*to
, const struct mbuf
*from
, int how
)
2529 KASSERT((to
->m_flags
& M_PKTHDR
), ("m_dup_pkthdr: not packet header"));
2531 to
->m_flags
= (from
->m_flags
& M_COPYFLAGS
) |
2532 (to
->m_flags
& ~M_COPYFLAGS
);
2533 to
->m_pkthdr
= from
->m_pkthdr
;
2534 SLIST_INIT(&to
->m_pkthdr
.tags
);
2535 return (m_tag_copy_chain(to
, from
, how
));
2539 * Defragment a mbuf chain, returning the shortest possible
2540 * chain of mbufs and clusters. If allocation fails and
2541 * this cannot be completed, NULL will be returned, but
2542 * the passed in chain will be unchanged. Upon success,
2543 * the original chain will be freed, and the new chain
2546 * If a non-packet header is passed in, the original
2547 * mbuf (chain?) will be returned unharmed.
2549 * m_defrag_nofree doesn't free the passed in mbuf.
2552 m_defrag(struct mbuf
*m0
, int how
)
2556 if ((m_new
= m_defrag_nofree(m0
, how
)) == NULL
)
2564 m_defrag_nofree(struct mbuf
*m0
, int how
)
2566 struct mbuf
*m_new
= NULL
, *m_final
= NULL
;
2567 int progress
= 0, length
, nsize
;
2569 if (!(m0
->m_flags
& M_PKTHDR
))
2572 #ifdef MBUF_STRESS_TEST
2573 if (m_defragrandomfailures
) {
2574 int temp
= karc4random() & 0xff;
2580 m_final
= m_getl(m0
->m_pkthdr
.len
, how
, MT_DATA
, M_PKTHDR
, &nsize
);
2581 if (m_final
== NULL
)
2583 m_final
->m_len
= 0; /* in case m0->m_pkthdr.len is zero */
2585 if (m_dup_pkthdr(m_final
, m0
, how
) == 0)
2590 while (progress
< m0
->m_pkthdr
.len
) {
2591 length
= m0
->m_pkthdr
.len
- progress
;
2592 if (length
> MCLBYTES
)
2595 if (m_new
== NULL
) {
2596 m_new
= m_getl(length
, how
, MT_DATA
, 0, &nsize
);
2601 m_copydata(m0
, progress
, length
, mtod(m_new
, caddr_t
));
2603 m_new
->m_len
= length
;
2604 if (m_new
!= m_final
)
2605 m_cat(m_final
, m_new
);
2608 if (m0
->m_next
== NULL
)
2611 m_defragbytes
+= m_final
->m_pkthdr
.len
;
2622 * Move data from uio into mbufs.
2625 m_uiomove(struct uio
*uio
)
2627 struct mbuf
*m
; /* current working mbuf */
2628 struct mbuf
*head
= NULL
; /* result mbuf chain */
2629 struct mbuf
**mp
= &head
;
2630 int flags
= M_PKTHDR
;
2636 if (uio
->uio_resid
> INT_MAX
)
2639 resid
= (int)uio
->uio_resid
;
2640 m
= m_getl(resid
, M_WAITOK
, MT_DATA
, flags
, &nsize
);
2642 m
->m_pkthdr
.len
= 0;
2643 /* Leave room for protocol headers. */
2648 m
->m_len
= imin(nsize
, resid
);
2649 error
= uiomove(mtod(m
, caddr_t
), m
->m_len
, uio
);
2656 head
->m_pkthdr
.len
+= m
->m_len
;
2657 } while (uio
->uio_resid
> 0);
2667 m_last(struct mbuf
*m
)
2675 * Return the number of bytes in an mbuf chain.
2676 * If lastm is not NULL, also return the last mbuf.
2679 m_lengthm(struct mbuf
*m
, struct mbuf
**lastm
)
2682 struct mbuf
*prev
= m
;
2695 * Like m_lengthm(), except also keep track of mbuf usage.
2698 m_countm(struct mbuf
*m
, struct mbuf
**lastm
, u_int
*pmbcnt
)
2700 u_int len
= 0, mbcnt
= 0;
2701 struct mbuf
*prev
= m
;
2706 if (m
->m_flags
& M_EXT
)
2707 mbcnt
+= m
->m_ext
.ext_size
;