network - Completely revamp the netisr / dispatch code
[dragonfly.git] / sys / kern / uipc_mbuf.c
CommitLineData
984263bc 1/*
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2 * (MPSAFE)
3 *
0c33f36d 4 * Copyright (c) 2004 Jeffrey M. Hsu. All rights reserved.
66d6c637
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5 * Copyright (c) 2004 The DragonFly Project. All rights reserved.
6 *
7 * This code is derived from software contributed to The DragonFly Project
8 * by Jeffrey M. Hsu.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
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.
21 *
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,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
66d6c637 36/*
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37 * Copyright (c) 1982, 1986, 1988, 1991, 1993
38 * The Regents of the University of California. All rights reserved.
39 *
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
42 * are met:
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
48 * 3. All advertising materials mentioning features or use of this software
49 * must display the following acknowledgement:
50 * This product includes software developed by the University of
51 * California, Berkeley and its contributors.
52 * 4. Neither the name of the University nor the names of its contributors
53 * may be used to endorse or promote products derived from this software
54 * without specific prior written permission.
55 *
56 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66 * SUCH DAMAGE.
67 *
8a3125c6 68 * @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94
984263bc 69 * $FreeBSD: src/sys/kern/uipc_mbuf.c,v 1.51.2.24 2003/04/15 06:59:29 silby Exp $
3f98f485 70 * $DragonFly: src/sys/kern/uipc_mbuf.c,v 1.70 2008/11/20 14:21:01 sephe Exp $
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71 */
72
73#include "opt_param.h"
74#include "opt_mbuf_stress_test.h"
75#include <sys/param.h>
76#include <sys/systm.h>
77#include <sys/malloc.h>
78#include <sys/mbuf.h>
79#include <sys/kernel.h>
80#include <sys/sysctl.h>
81#include <sys/domain.h>
7b6f875f 82#include <sys/objcache.h>
e9fa4b60 83#include <sys/tree.h>
984263bc 84#include <sys/protosw.h>
0c33f36d 85#include <sys/uio.h>
ef0fdad1 86#include <sys/thread.h>
a2a5ad0d 87#include <sys/globaldata.h>
5bd48c1d 88
90775e29 89#include <sys/thread2.h>
5bd48c1d 90#include <sys/spinlock2.h>
984263bc 91
1d16b2b5 92#include <machine/atomic.h>
e54488bb 93#include <machine/limits.h>
1d16b2b5 94
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95#include <vm/vm.h>
96#include <vm/vm_kern.h>
97#include <vm/vm_extern.h>
98
99#ifdef INVARIANTS
100#include <machine/cpu.h>
101#endif
102
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103/*
104 * mbuf cluster meta-data
105 */
7b6f875f 106struct mbcluster {
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107 int32_t mcl_refs;
108 void *mcl_data;
7b6f875f 109};
90775e29 110
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111/*
112 * mbuf tracking for debugging purposes
113 */
114#ifdef MBUF_DEBUG
115
116static MALLOC_DEFINE(M_MTRACK, "mtrack", "mtrack");
117
118struct mbctrack;
119RB_HEAD(mbuf_rb_tree, mbtrack);
120RB_PROTOTYPE2(mbuf_rb_tree, mbtrack, rb_node, mbtrack_cmp, struct mbuf *);
121
122struct mbtrack {
123 RB_ENTRY(mbtrack) rb_node;
124 int trackid;
125 struct mbuf *m;
126};
127
128static int
129mbtrack_cmp(struct mbtrack *mb1, struct mbtrack *mb2)
130{
131 if (mb1->m < mb2->m)
132 return(-1);
133 if (mb1->m > mb2->m)
134 return(1);
135 return(0);
136}
137
138RB_GENERATE2(mbuf_rb_tree, mbtrack, rb_node, mbtrack_cmp, struct mbuf *, m);
139
140struct mbuf_rb_tree mbuf_track_root;
5bd48c1d 141static struct spinlock mbuf_track_spin = SPINLOCK_INITIALIZER(mbuf_track_spin);
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142
143static void
144mbuftrack(struct mbuf *m)
145{
146 struct mbtrack *mbt;
147
e9fa4b60 148 mbt = kmalloc(sizeof(*mbt), M_MTRACK, M_INTWAIT|M_ZERO);
5bd48c1d 149 spin_lock(&mbuf_track_spin);
e9fa4b60 150 mbt->m = m;
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151 if (mbuf_rb_tree_RB_INSERT(&mbuf_track_root, mbt)) {
152 spin_unlock(&mbuf_track_spin);
e9fa4b60 153 panic("mbuftrack: mbuf %p already being tracked\n", m);
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154 }
155 spin_unlock(&mbuf_track_spin);
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156}
157
158static void
159mbufuntrack(struct mbuf *m)
160{
161 struct mbtrack *mbt;
162
5bd48c1d 163 spin_lock(&mbuf_track_spin);
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164 mbt = mbuf_rb_tree_RB_LOOKUP(&mbuf_track_root, m);
165 if (mbt == NULL) {
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166 spin_unlock(&mbuf_track_spin);
167 panic("mbufuntrack: mbuf %p was not tracked\n", m);
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168 } else {
169 mbuf_rb_tree_RB_REMOVE(&mbuf_track_root, mbt);
170 kfree(mbt, M_MTRACK);
171 }
5bd48c1d 172 spin_unlock(&mbuf_track_spin);
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173}
174
175void
176mbuftrackid(struct mbuf *m, int trackid)
177{
178 struct mbtrack *mbt;
179 struct mbuf *n;
180
5bd48c1d 181 spin_lock(&mbuf_track_spin);
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182 while (m) {
183 n = m->m_nextpkt;
184 while (m) {
185 mbt = mbuf_rb_tree_RB_LOOKUP(&mbuf_track_root, m);
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186 if (mbt == NULL) {
187 spin_unlock(&mbuf_track_spin);
188 panic("mbuftrackid: mbuf %p not tracked", m);
189 }
190 mbt->trackid = trackid;
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191 m = m->m_next;
192 }
193 m = n;
194 }
5bd48c1d 195 spin_unlock(&mbuf_track_spin);
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196}
197
198static int
199mbuftrack_callback(struct mbtrack *mbt, void *arg)
200{
201 struct sysctl_req *req = arg;
202 char buf[64];
203 int error;
204
205 ksnprintf(buf, sizeof(buf), "mbuf %p track %d\n", mbt->m, mbt->trackid);
206
5bd48c1d 207 spin_unlock(&mbuf_track_spin);
e9fa4b60 208 error = SYSCTL_OUT(req, buf, strlen(buf));
5bd48c1d 209 spin_lock(&mbuf_track_spin);
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210 if (error)
211 return(-error);
212 return(0);
213}
214
215static int
216mbuftrack_show(SYSCTL_HANDLER_ARGS)
217{
218 int error;
219
5bd48c1d 220 spin_lock(&mbuf_track_spin);
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221 error = mbuf_rb_tree_RB_SCAN(&mbuf_track_root, NULL,
222 mbuftrack_callback, req);
5bd48c1d 223 spin_unlock(&mbuf_track_spin);
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224 return (-error);
225}
226SYSCTL_PROC(_kern_ipc, OID_AUTO, showmbufs, CTLFLAG_RD|CTLTYPE_STRING,
227 0, 0, mbuftrack_show, "A", "Show all in-use mbufs");
228
229#else
230
231#define mbuftrack(m)
232#define mbufuntrack(m)
233
234#endif
235
7b6f875f 236static void mbinit(void *);
ba39e2e0 237SYSINIT(mbuf, SI_BOOT2_MACHDEP, SI_ORDER_FIRST, mbinit, NULL)
984263bc 238
4c1e2509 239static u_long mbtypes[SMP_MAXCPU][MT_NTYPES];
90775e29 240
4c1e2509 241static struct mbstat mbstat[SMP_MAXCPU];
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242int max_linkhdr;
243int max_protohdr;
244int max_hdr;
245int max_datalen;
246int m_defragpackets;
247int m_defragbytes;
248int m_defraguseless;
249int m_defragfailure;
250#ifdef MBUF_STRESS_TEST
251int m_defragrandomfailures;
252#endif
253
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254struct objcache *mbuf_cache, *mbufphdr_cache;
255struct objcache *mclmeta_cache;
256struct objcache *mbufcluster_cache, *mbufphdrcluster_cache;
257
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258int nmbclusters;
259int nmbufs;
984263bc 260
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261SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RW,
262 &max_linkhdr, 0, "");
263SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RW,
264 &max_protohdr, 0, "");
265SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RW, &max_hdr, 0, "");
266SYSCTL_INT(_kern_ipc, KIPC_MAX_DATALEN, max_datalen, CTLFLAG_RW,
267 &max_datalen, 0, "");
268SYSCTL_INT(_kern_ipc, OID_AUTO, mbuf_wait, CTLFLAG_RW,
269 &mbuf_wait, 0, "");
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270static int do_mbstat(SYSCTL_HANDLER_ARGS);
271
272SYSCTL_PROC(_kern_ipc, KIPC_MBSTAT, mbstat, CTLTYPE_STRUCT|CTLFLAG_RD,
273 0, 0, do_mbstat, "S,mbstat", "");
274
275static int do_mbtypes(SYSCTL_HANDLER_ARGS);
276
277SYSCTL_PROC(_kern_ipc, OID_AUTO, mbtypes, CTLTYPE_ULONG|CTLFLAG_RD,
278 0, 0, do_mbtypes, "LU", "");
279
280static int
281do_mbstat(SYSCTL_HANDLER_ARGS)
282{
283 struct mbstat mbstat_total;
284 struct mbstat *mbstat_totalp;
285 int i;
286
287 bzero(&mbstat_total, sizeof(mbstat_total));
288 mbstat_totalp = &mbstat_total;
289
290 for (i = 0; i < ncpus; i++)
291 {
292 mbstat_total.m_mbufs += mbstat[i].m_mbufs;
293 mbstat_total.m_clusters += mbstat[i].m_clusters;
294 mbstat_total.m_spare += mbstat[i].m_spare;
295 mbstat_total.m_clfree += mbstat[i].m_clfree;
296 mbstat_total.m_drops += mbstat[i].m_drops;
297 mbstat_total.m_wait += mbstat[i].m_wait;
298 mbstat_total.m_drain += mbstat[i].m_drain;
299 mbstat_total.m_mcfail += mbstat[i].m_mcfail;
300 mbstat_total.m_mpfail += mbstat[i].m_mpfail;
301
302 }
303 /*
304 * The following fields are not cumulative fields so just
305 * get their values once.
306 */
307 mbstat_total.m_msize = mbstat[0].m_msize;
308 mbstat_total.m_mclbytes = mbstat[0].m_mclbytes;
309 mbstat_total.m_minclsize = mbstat[0].m_minclsize;
310 mbstat_total.m_mlen = mbstat[0].m_mlen;
311 mbstat_total.m_mhlen = mbstat[0].m_mhlen;
312
313 return(sysctl_handle_opaque(oidp, mbstat_totalp, sizeof(mbstat_total), req));
314}
315
316static int
317do_mbtypes(SYSCTL_HANDLER_ARGS)
318{
319 u_long totals[MT_NTYPES];
320 int i, j;
321
322 for (i = 0; i < MT_NTYPES; i++)
323 totals[i] = 0;
324
325 for (i = 0; i < ncpus; i++)
326 {
327 for (j = 0; j < MT_NTYPES; j++)
328 totals[j] += mbtypes[i][j];
329 }
330
331 return(sysctl_handle_opaque(oidp, totals, sizeof(totals), req));
332}
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333
334/*
335 * These are read-only because we do not currently have any code
336 * to adjust the objcache limits after the fact. The variables
337 * may only be set as boot-time tunables.
338 */
339SYSCTL_INT(_kern_ipc, KIPC_NMBCLUSTERS, nmbclusters, CTLFLAG_RD,
984263bc 340 &nmbclusters, 0, "Maximum number of mbuf clusters available");
18c48b9c 341SYSCTL_INT(_kern_ipc, OID_AUTO, nmbufs, CTLFLAG_RD, &nmbufs, 0,
984263bc 342 "Maximum number of mbufs available");
7b6f875f 343
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344SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragpackets, CTLFLAG_RD,
345 &m_defragpackets, 0, "");
346SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragbytes, CTLFLAG_RD,
347 &m_defragbytes, 0, "");
348SYSCTL_INT(_kern_ipc, OID_AUTO, m_defraguseless, CTLFLAG_RD,
349 &m_defraguseless, 0, "");
350SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragfailure, CTLFLAG_RD,
351 &m_defragfailure, 0, "");
352#ifdef MBUF_STRESS_TEST
353SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragrandomfailures, CTLFLAG_RW,
354 &m_defragrandomfailures, 0, "");
355#endif
356
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357static MALLOC_DEFINE(M_MBUF, "mbuf", "mbuf");
358static MALLOC_DEFINE(M_MBUFCL, "mbufcl", "mbufcl");
7b6f875f 359static MALLOC_DEFINE(M_MCLMETA, "mclmeta", "mclmeta");
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360
361static void m_reclaim (void);
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362static void m_mclref(void *arg);
363static void m_mclfree(void *arg);
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364
365#ifndef NMBCLUSTERS
366#define NMBCLUSTERS (512 + maxusers * 16)
367#endif
368#ifndef NMBUFS
7b6f875f 369#define NMBUFS (nmbclusters * 2)
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370#endif
371
372/*
373 * Perform sanity checks of tunables declared above.
374 */
375static void
376tunable_mbinit(void *dummy)
377{
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378 /*
379 * This has to be done before VM init.
380 */
381 nmbclusters = NMBCLUSTERS;
382 TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters);
383 nmbufs = NMBUFS;
384 TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs);
385 /* Sanity checks */
386 if (nmbufs < nmbclusters * 2)
387 nmbufs = nmbclusters * 2;
984263bc 388}
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389SYSINIT(tunable_mbinit, SI_BOOT1_TUNABLES, SI_ORDER_ANY,
390 tunable_mbinit, NULL);
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391
392/* "number of clusters of pages" */
393#define NCL_INIT 1
394
395#define NMB_INIT 16
396
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397/*
398 * The mbuf object cache only guarantees that m_next and m_nextpkt are
399 * NULL and that m_data points to the beginning of the data area. In
400 * particular, m_len and m_pkthdr.len are uninitialized. It is the
401 * responsibility of the caller to initialize those fields before use.
402 */
403
404static boolean_t __inline
405mbuf_ctor(void *obj, void *private, int ocflags)
984263bc 406{
7b6f875f 407 struct mbuf *m = obj;
984263bc 408
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409 m->m_next = NULL;
410 m->m_nextpkt = NULL;
411 m->m_data = m->m_dat;
412 m->m_flags = 0;
413
414 return (TRUE);
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415}
416
417/*
7b6f875f 418 * Initialize the mbuf and the packet header fields.
984263bc 419 */
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420static boolean_t
421mbufphdr_ctor(void *obj, void *private, int ocflags)
984263bc 422{
7b6f875f 423 struct mbuf *m = obj;
984263bc 424
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425 m->m_next = NULL;
426 m->m_nextpkt = NULL;
427 m->m_data = m->m_pktdat;
77e294a1 428 m->m_flags = M_PKTHDR | M_PHCACHE;
984263bc 429
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430 m->m_pkthdr.rcvif = NULL; /* eliminate XXX JH */
431 SLIST_INIT(&m->m_pkthdr.tags);
432 m->m_pkthdr.csum_flags = 0; /* eliminate XXX JH */
433 m->m_pkthdr.fw_flags = 0; /* eliminate XXX JH */
434
435 return (TRUE);
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436}
437
438/*
7b6f875f 439 * A mbcluster object consists of 2K (MCLBYTES) cluster and a refcount.
984263bc 440 */
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441static boolean_t
442mclmeta_ctor(void *obj, void *private, int ocflags)
984263bc 443{
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444 struct mbcluster *cl = obj;
445 void *buf;
446
447 if (ocflags & M_NOWAIT)
efda3bd0 448 buf = kmalloc(MCLBYTES, M_MBUFCL, M_NOWAIT | M_ZERO);
7b6f875f 449 else
efda3bd0 450 buf = kmalloc(MCLBYTES, M_MBUFCL, M_INTWAIT | M_ZERO);
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451 if (buf == NULL)
452 return (FALSE);
77e294a1 453 cl->mcl_refs = 0;
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454 cl->mcl_data = buf;
455 return (TRUE);
456}
984263bc 457
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458static void
459mclmeta_dtor(void *obj, void *private)
460{
461 struct mbcluster *mcl = obj;
462
463 KKASSERT(mcl->mcl_refs == 0);
efda3bd0 464 kfree(mcl->mcl_data, M_MBUFCL);
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465}
466
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467static void
468linkcluster(struct mbuf *m, struct mbcluster *cl)
469{
984263bc 470 /*
7b6f875f
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471 * Add the cluster to the mbuf. The caller will detect that the
472 * mbuf now has an attached cluster.
984263bc 473 */
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474 m->m_ext.ext_arg = cl;
475 m->m_ext.ext_buf = cl->mcl_data;
476 m->m_ext.ext_ref = m_mclref;
477 m->m_ext.ext_free = m_mclfree;
478 m->m_ext.ext_size = MCLBYTES;
df8d1020 479 atomic_add_int(&cl->mcl_refs, 1);
984263bc 480
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481 m->m_data = m->m_ext.ext_buf;
482 m->m_flags |= M_EXT | M_EXT_CLUSTER;
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MD
483}
484
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485static boolean_t
486mbufphdrcluster_ctor(void *obj, void *private, int ocflags)
487{
488 struct mbuf *m = obj;
489 struct mbcluster *cl;
490
491 mbufphdr_ctor(obj, private, ocflags);
492 cl = objcache_get(mclmeta_cache, ocflags);
a5955b15
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493 if (cl == NULL) {
494 ++mbstat[mycpu->gd_cpuid].m_drops;
7b6f875f 495 return (FALSE);
a5955b15 496 }
77e294a1 497 m->m_flags |= M_CLCACHE;
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JH
498 linkcluster(m, cl);
499 return (TRUE);
500}
984263bc 501
7b6f875f
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502static boolean_t
503mbufcluster_ctor(void *obj, void *private, int ocflags)
984263bc 504{
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505 struct mbuf *m = obj;
506 struct mbcluster *cl;
507
508 mbuf_ctor(obj, private, ocflags);
509 cl = objcache_get(mclmeta_cache, ocflags);
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510 if (cl == NULL) {
511 ++mbstat[mycpu->gd_cpuid].m_drops;
7b6f875f 512 return (FALSE);
a5955b15 513 }
77e294a1 514 m->m_flags |= M_CLCACHE;
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JH
515 linkcluster(m, cl);
516 return (TRUE);
517}
984263bc 518
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MD
519/*
520 * Used for both the cluster and cluster PHDR caches.
521 *
522 * The mbuf may have lost its cluster due to sharing, deal
523 * with the situation by checking M_EXT.
524 */
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JH
525static void
526mbufcluster_dtor(void *obj, void *private)
984263bc 527{
7b6f875f 528 struct mbuf *m = obj;
77e294a1 529 struct mbcluster *mcl;
984263bc 530
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MD
531 if (m->m_flags & M_EXT) {
532 KKASSERT((m->m_flags & M_EXT_CLUSTER) != 0);
533 mcl = m->m_ext.ext_arg;
534 KKASSERT(mcl->mcl_refs == 1);
535 mcl->mcl_refs = 0;
536 objcache_put(mclmeta_cache, mcl);
537 }
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MD
538}
539
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540struct objcache_malloc_args mbuf_malloc_args = { MSIZE, M_MBUF };
541struct objcache_malloc_args mclmeta_malloc_args =
542 { sizeof(struct mbcluster), M_MCLMETA };
543
544/* ARGSUSED*/
90775e29 545static void
7b6f875f 546mbinit(void *dummy)
984263bc 547{
6f21e2f4 548 int mb_limit, cl_limit;
0aa16b5d 549 int limit;
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550 int i;
551
0aa16b5d
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552 /*
553 * Initialize statistics
554 */
555 for (i = 0; i < ncpus; i++) {
4c1e2509
JT
556 atomic_set_long_nonlocked(&mbstat[i].m_msize, MSIZE);
557 atomic_set_long_nonlocked(&mbstat[i].m_mclbytes, MCLBYTES);
558 atomic_set_long_nonlocked(&mbstat[i].m_minclsize, MINCLSIZE);
559 atomic_set_long_nonlocked(&mbstat[i].m_mlen, MLEN);
560 atomic_set_long_nonlocked(&mbstat[i].m_mhlen, MHLEN);
561 }
984263bc 562
0aa16b5d
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563 /*
564 * Create objtect caches and save cluster limits, which will
565 * be used to adjust backing kmalloc pools' limit later.
566 */
567
6f21e2f4 568 mb_limit = cl_limit = 0;
0aa16b5d
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569
570 limit = nmbufs;
571 mbuf_cache = objcache_create("mbuf", &limit, 0,
5b7da64a 572 mbuf_ctor, NULL, NULL,
7b6f875f 573 objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args);
6f21e2f4 574 mb_limit += limit;
0aa16b5d
SZ
575
576 limit = nmbufs;
577 mbufphdr_cache = objcache_create("mbuf pkt hdr", &limit, 64,
5b7da64a 578 mbufphdr_ctor, NULL, NULL,
7b6f875f 579 objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args);
6f21e2f4 580 mb_limit += limit;
0aa16b5d
SZ
581
582 cl_limit = nmbclusters;
583 mclmeta_cache = objcache_create("cluster mbuf", &cl_limit, 0,
7b6f875f
JH
584 mclmeta_ctor, mclmeta_dtor, NULL,
585 objcache_malloc_alloc, objcache_malloc_free, &mclmeta_malloc_args);
0aa16b5d
SZ
586
587 limit = nmbclusters;
588 mbufcluster_cache = objcache_create("mbuf + cluster", &limit, 0,
7b6f875f
JH
589 mbufcluster_ctor, mbufcluster_dtor, NULL,
590 objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args);
6f21e2f4 591 mb_limit += limit;
0aa16b5d
SZ
592
593 limit = nmbclusters;
7b6f875f 594 mbufphdrcluster_cache = objcache_create("mbuf pkt hdr + cluster",
0aa16b5d 595 &limit, 64, mbufphdrcluster_ctor, mbufcluster_dtor, NULL,
7b6f875f 596 objcache_malloc_alloc, objcache_malloc_free, &mbuf_malloc_args);
6f21e2f4 597 mb_limit += limit;
0aa16b5d
SZ
598
599 /*
600 * Adjust backing kmalloc pools' limit
3f98f485
SZ
601 *
602 * NOTE: We raise the limit by another 1/8 to take the effect
603 * of loosememuse into account.
0aa16b5d 604 */
3f98f485 605 cl_limit += cl_limit / 8;
0aa16b5d
SZ
606 kmalloc_raise_limit(mclmeta_malloc_args.mtype,
607 mclmeta_malloc_args.objsize * cl_limit);
608 kmalloc_raise_limit(M_MBUFCL, MCLBYTES * cl_limit);
609
3f98f485 610 mb_limit += mb_limit / 8;
0aa16b5d
SZ
611 kmalloc_raise_limit(mbuf_malloc_args.mtype,
612 mbuf_malloc_args.objsize * mb_limit);
90775e29 613}
984263bc 614
90775e29
MD
615/*
616 * Return the number of references to this mbuf's data. 0 is returned
617 * if the mbuf is not M_EXT, a reference count is returned if it is
7b6f875f 618 * M_EXT | M_EXT_CLUSTER, and 99 is returned if it is a special M_EXT.
90775e29
MD
619 */
620int
621m_sharecount(struct mbuf *m)
622{
7b6f875f
JH
623 switch (m->m_flags & (M_EXT | M_EXT_CLUSTER)) {
624 case 0:
625 return (0);
626 case M_EXT:
627 return (99);
628 case M_EXT | M_EXT_CLUSTER:
629 return (((struct mbcluster *)m->m_ext.ext_arg)->mcl_refs);
630 }
631 /* NOTREACHED */
632 return (0); /* to shut up compiler */
90775e29
MD
633}
634
635/*
636 * change mbuf to new type
637 */
638void
639m_chtype(struct mbuf *m, int type)
640{
4c1e2509
JT
641 struct globaldata *gd = mycpu;
642
643 atomic_add_long_nonlocked(&mbtypes[gd->gd_cpuid][type], 1);
644 atomic_subtract_long_nonlocked(&mbtypes[gd->gd_cpuid][m->m_type], 1);
645 atomic_set_short_nonlocked(&m->m_type, type);
984263bc
MD
646}
647
984263bc 648static void
8a3125c6 649m_reclaim(void)
984263bc 650{
1fd87d54
RG
651 struct domain *dp;
652 struct protosw *pr;
984263bc 653
5bd48c1d
MD
654 kprintf("Debug: m_reclaim() called\n");
655
9c70fe43 656 SLIST_FOREACH(dp, &domains, dom_next) {
8a3125c6 657 for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) {
984263bc
MD
658 if (pr->pr_drain)
659 (*pr->pr_drain)();
8a3125c6
MD
660 }
661 }
4c1e2509 662 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_drain, 1);
984263bc
MD
663}
664
7b6f875f
JH
665static void __inline
666updatestats(struct mbuf *m, int type)
667{
4c1e2509 668 struct globaldata *gd = mycpu;
7b6f875f
JH
669 m->m_type = type;
670
e9fa4b60 671 mbuftrack(m);
4c1e2509
JT
672
673 atomic_add_long_nonlocked(&mbtypes[gd->gd_cpuid][type], 1);
674 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mbufs, 1);
675
7b6f875f
JH
676}
677
984263bc 678/*
7b6f875f 679 * Allocate an mbuf.
984263bc
MD
680 */
681struct mbuf *
8a3125c6 682m_get(int how, int type)
984263bc 683{
12496bdf 684 struct mbuf *m;
7b6f875f
JH
685 int ntries = 0;
686 int ocf = MBTOM(how);
12496bdf 687
7b6f875f
JH
688retryonce:
689
690 m = objcache_get(mbuf_cache, ocf);
691
692 if (m == NULL) {
693 if ((how & MB_TRYWAIT) && ntries++ == 0) {
694 struct objcache *reclaimlist[] = {
695 mbufphdr_cache,
5bd48c1d
MD
696 mbufcluster_cache,
697 mbufphdrcluster_cache
7b6f875f
JH
698 };
699 const int nreclaims = __arysize(reclaimlist);
700
701 if (!objcache_reclaimlist(reclaimlist, nreclaims, ocf))
702 m_reclaim();
703 goto retryonce;
c6339e39 704 }
a5955b15 705 ++mbstat[mycpu->gd_cpuid].m_drops;
7b6f875f 706 return (NULL);
12496bdf 707 }
c6339e39 708
7b6f875f 709 updatestats(m, type);
984263bc
MD
710 return (m);
711}
712
713struct mbuf *
8a3125c6 714m_gethdr(int how, int type)
984263bc 715{
12496bdf 716 struct mbuf *m;
7b6f875f
JH
717 int ocf = MBTOM(how);
718 int ntries = 0;
12496bdf 719
7b6f875f
JH
720retryonce:
721
722 m = objcache_get(mbufphdr_cache, ocf);
723
724 if (m == NULL) {
725 if ((how & MB_TRYWAIT) && ntries++ == 0) {
726 struct objcache *reclaimlist[] = {
727 mbuf_cache,
728 mbufcluster_cache, mbufphdrcluster_cache
729 };
730 const int nreclaims = __arysize(reclaimlist);
731
732 if (!objcache_reclaimlist(reclaimlist, nreclaims, ocf))
733 m_reclaim();
734 goto retryonce;
c6339e39 735 }
a5955b15 736 ++mbstat[mycpu->gd_cpuid].m_drops;
7b6f875f 737 return (NULL);
12496bdf 738 }
c6339e39 739
7b6f875f 740 updatestats(m, type);
984263bc
MD
741 return (m);
742}
743
7b6f875f
JH
744/*
745 * Get a mbuf (not a mbuf cluster!) and zero it.
746 * Deprecated.
747 */
984263bc 748struct mbuf *
8a3125c6 749m_getclr(int how, int type)
984263bc 750{
1fd87d54 751 struct mbuf *m;
984263bc 752
7b6f875f
JH
753 m = m_get(how, type);
754 if (m != NULL)
755 bzero(m->m_data, MLEN);
984263bc
MD
756 return (m);
757}
758
759/*
7b6f875f 760 * Returns an mbuf with an attached cluster.
984263bc
MD
761 * Because many network drivers use this kind of buffers a lot, it is
762 * convenient to keep a small pool of free buffers of this kind.
763 * Even a small size such as 10 gives about 10% improvement in the
764 * forwarding rate in a bridge or router.
984263bc 765 */
984263bc
MD
766struct mbuf *
767m_getcl(int how, short type, int flags)
768{
7b6f875f
JH
769 struct mbuf *m;
770 int ocflags = MBTOM(how);
771 int ntries = 0;
984263bc 772
7b6f875f
JH
773retryonce:
774
775 if (flags & M_PKTHDR)
776 m = objcache_get(mbufphdrcluster_cache, ocflags);
777 else
778 m = objcache_get(mbufcluster_cache, ocflags);
779
780 if (m == NULL) {
781 if ((how & MB_TRYWAIT) && ntries++ == 0) {
782 struct objcache *reclaimlist[1];
783
784 if (flags & M_PKTHDR)
785 reclaimlist[0] = mbufcluster_cache;
786 else
787 reclaimlist[0] = mbufphdrcluster_cache;
788 if (!objcache_reclaimlist(reclaimlist, 1, ocflags))
789 m_reclaim();
790 goto retryonce;
984263bc 791 }
a5955b15 792 ++mbstat[mycpu->gd_cpuid].m_drops;
7b6f875f 793 return (NULL);
984263bc 794 }
7b6f875f
JH
795
796 m->m_type = type;
797
e9fa4b60 798 mbuftrack(m);
4c1e2509
JT
799
800 atomic_add_long_nonlocked(&mbtypes[mycpu->gd_cpuid][type], 1);
801 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, 1);
7b6f875f 802 return (m);
984263bc
MD
803}
804
805/*
50503f0f
JH
806 * Allocate chain of requested length.
807 */
808struct mbuf *
809m_getc(int len, int how, int type)
810{
811 struct mbuf *n, *nfirst = NULL, **ntail = &nfirst;
812 int nsize;
813
814 while (len > 0) {
815 n = m_getl(len, how, type, 0, &nsize);
816 if (n == NULL)
817 goto failed;
818 n->m_len = 0;
819 *ntail = n;
820 ntail = &n->m_next;
821 len -= nsize;
822 }
823 return (nfirst);
824
825failed:
826 m_freem(nfirst);
827 return (NULL);
828}
829
830/*
831 * Allocate len-worth of mbufs and/or mbuf clusters (whatever fits best)
832 * and return a pointer to the head of the allocated chain. If m0 is
984263bc
MD
833 * non-null, then we assume that it is a single mbuf or an mbuf chain to
834 * which we want len bytes worth of mbufs and/or clusters attached, and so
50503f0f 835 * if we succeed in allocating it, we will just return a pointer to m0.
984263bc
MD
836 *
837 * If we happen to fail at any point during the allocation, we will free
838 * up everything we have already allocated and return NULL.
839 *
50503f0f 840 * Deprecated. Use m_getc() and m_cat() instead.
984263bc
MD
841 */
842struct mbuf *
dc14b0a9 843m_getm(struct mbuf *m0, int len, int type, int how)
984263bc 844{
50503f0f 845 struct mbuf *nfirst;
984263bc 846
50503f0f 847 nfirst = m_getc(len, how, type);
984263bc 848
50503f0f
JH
849 if (m0 != NULL) {
850 m_last(m0)->m_next = nfirst;
851 return (m0);
984263bc
MD
852 }
853
50503f0f 854 return (nfirst);
984263bc
MD
855}
856
857/*
7b6f875f
JH
858 * Adds a cluster to a normal mbuf, M_EXT is set on success.
859 * Deprecated. Use m_getcl() instead.
b6650ec0 860 */
90775e29
MD
861void
862m_mclget(struct mbuf *m, int how)
b6650ec0 863{
7b6f875f 864 struct mbcluster *mcl;
b6650ec0 865
77e294a1 866 KKASSERT((m->m_flags & M_EXT) == 0);
7b6f875f 867 mcl = objcache_get(mclmeta_cache, MBTOM(how));
c3ef87ca
MD
868 if (mcl != NULL) {
869 linkcluster(m, mcl);
5bd48c1d
MD
870 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters,
871 1);
a5955b15
MD
872 } else {
873 ++mbstat[mycpu->gd_cpuid].m_drops;
c3ef87ca 874 }
b6650ec0
MD
875}
876
df8d1020
MD
877/*
878 * Updates to mbcluster must be MPSAFE. Only an entity which already has
879 * a reference to the cluster can ref it, so we are in no danger of
880 * racing an add with a subtract. But the operation must still be atomic
881 * since multiple entities may have a reference on the cluster.
882 *
883 * m_mclfree() is almost the same but it must contend with two entities
5bd48c1d 884 * freeing the cluster at the same time.
df8d1020 885 */
90775e29 886static void
7b6f875f 887m_mclref(void *arg)
b6650ec0 888{
7b6f875f 889 struct mbcluster *mcl = arg;
90775e29 890
7b6f875f 891 atomic_add_int(&mcl->mcl_refs, 1);
b6650ec0
MD
892}
893
1d16b2b5
MD
894/*
895 * When dereferencing a cluster we have to deal with a N->0 race, where
896 * N entities free their references simultaniously. To do this we use
dee87a60 897 * atomic_fetchadd_int().
1d16b2b5 898 */
90775e29 899static void
7b6f875f 900m_mclfree(void *arg)
b6650ec0 901{
7b6f875f 902 struct mbcluster *mcl = arg;
90775e29 903
dee87a60 904 if (atomic_fetchadd_int(&mcl->mcl_refs, -1) == 1)
77e294a1 905 objcache_put(mclmeta_cache, mcl);
b6650ec0
MD
906}
907
908/*
b6650ec0
MD
909 * Free a single mbuf and any associated external storage. The successor,
910 * if any, is returned.
984263bc 911 *
b6650ec0 912 * We do need to check non-first mbuf for m_aux, since some of existing
984263bc
MD
913 * code does not call M_PREPEND properly.
914 * (example: call to bpf_mtap from drivers)
915 */
984263bc 916struct mbuf *
b6650ec0 917m_free(struct mbuf *m)
984263bc 918{
b6650ec0 919 struct mbuf *n;
4c1e2509 920 struct globaldata *gd = mycpu;
b6650ec0 921
361af367 922 KASSERT(m->m_type != MT_FREE, ("freeing free mbuf %p", m));
4c1e2509 923 atomic_subtract_long_nonlocked(&mbtypes[gd->gd_cpuid][m->m_type], 1);
90775e29 924
7b6f875f 925 n = m->m_next;
90775e29
MD
926
927 /*
7b6f875f
JH
928 * Make sure the mbuf is in constructed state before returning it
929 * to the objcache.
90775e29 930 */
90775e29 931 m->m_next = NULL;
e9fa4b60 932 mbufuntrack(m);
7b6f875f
JH
933#ifdef notyet
934 KKASSERT(m->m_nextpkt == NULL);
935#else
936 if (m->m_nextpkt != NULL) {
7b6f875f
JH
937 static int afewtimes = 10;
938
939 if (afewtimes-- > 0) {
6ea70f76 940 kprintf("mfree: m->m_nextpkt != NULL\n");
7ce2998e 941 print_backtrace(-1);
90775e29 942 }
7b6f875f
JH
943 m->m_nextpkt = NULL;
944 }
945#endif
946 if (m->m_flags & M_PKTHDR) {
7b6f875f 947 m_tag_delete_chain(m); /* eliminate XXX JH */
77e294a1
MD
948 }
949
950 m->m_flags &= (M_EXT | M_EXT_CLUSTER | M_CLCACHE | M_PHCACHE);
951
952 /*
953 * Clean the M_PKTHDR state so we can return the mbuf to its original
954 * cache. This is based on the PHCACHE flag which tells us whether
955 * the mbuf was originally allocated out of a packet-header cache
956 * or a non-packet-header cache.
957 */
958 if (m->m_flags & M_PHCACHE) {
959 m->m_flags |= M_PKTHDR;
960 m->m_pkthdr.rcvif = NULL; /* eliminate XXX JH */
7b6f875f
JH
961 m->m_pkthdr.csum_flags = 0; /* eliminate XXX JH */
962 m->m_pkthdr.fw_flags = 0; /* eliminate XXX JH */
6b1d6bed 963 SLIST_INIT(&m->m_pkthdr.tags);
90775e29 964 }
7b6f875f 965
77e294a1
MD
966 /*
967 * Handle remaining flags combinations. M_CLCACHE tells us whether
968 * the mbuf was originally allocated from a cluster cache or not,
969 * and is totally separate from whether the mbuf is currently
970 * associated with a cluster.
971 */
77e294a1
MD
972 switch(m->m_flags & (M_CLCACHE | M_EXT | M_EXT_CLUSTER)) {
973 case M_CLCACHE | M_EXT | M_EXT_CLUSTER:
974 /*
975 * mbuf+cluster cache case. The mbuf was allocated from the
976 * combined mbuf_cluster cache and can be returned to the
977 * cache if the cluster hasn't been shared.
978 */
979 if (m_sharecount(m) == 1) {
980 /*
981 * The cluster has not been shared, we can just
982 * reset the data pointer and return the mbuf
983 * to the cluster cache. Note that the reference
984 * count is left intact (it is still associated with
985 * an mbuf).
986 */
987 m->m_data = m->m_ext.ext_buf;
988 if (m->m_flags & M_PHCACHE)
989 objcache_put(mbufphdrcluster_cache, m);
990 else
991 objcache_put(mbufcluster_cache, m);
4c1e2509 992 atomic_subtract_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, 1);
77e294a1
MD
993 } else {
994 /*
995 * Hell. Someone else has a ref on this cluster,
996 * we have to disconnect it which means we can't
997 * put it back into the mbufcluster_cache, we
998 * have to destroy the mbuf.
999 *
cb086467
MD
1000 * Other mbuf references to the cluster will typically
1001 * be M_EXT | M_EXT_CLUSTER but without M_CLCACHE.
1002 *
77e294a1
MD
1003 * XXX we could try to connect another cluster to
1004 * it.
1005 */
7b6f875f
JH
1006 m->m_ext.ext_free(m->m_ext.ext_arg);
1007 m->m_flags &= ~(M_EXT | M_EXT_CLUSTER);
77e294a1
MD
1008 if (m->m_flags & M_PHCACHE)
1009 objcache_dtor(mbufphdrcluster_cache, m);
1010 else
1011 objcache_dtor(mbufcluster_cache, m);
7b6f875f 1012 }
77e294a1
MD
1013 break;
1014 case M_EXT | M_EXT_CLUSTER:
1015 /*
1016 * Normal cluster associated with an mbuf that was allocated
1017 * from the normal mbuf pool rather then the cluster pool.
1018 * The cluster has to be independantly disassociated from the
1019 * mbuf.
1020 */
cb086467 1021 if (m_sharecount(m) == 1)
4c1e2509 1022 atomic_subtract_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_clusters, 1);
77e294a1
MD
1023 /* fall through */
1024 case M_EXT:
1025 /*
1026 * Normal cluster association case, disconnect the cluster from
1027 * the mbuf. The cluster may or may not be custom.
1028 */
1029 m->m_ext.ext_free(m->m_ext.ext_arg);
1030 m->m_flags &= ~(M_EXT | M_EXT_CLUSTER);
1031 /* fall through */
1032 case 0:
1033 /*
1034 * return the mbuf to the mbuf cache.
1035 */
1036 if (m->m_flags & M_PHCACHE) {
7b6f875f
JH
1037 m->m_data = m->m_pktdat;
1038 objcache_put(mbufphdr_cache, m);
90775e29 1039 } else {
7b6f875f
JH
1040 m->m_data = m->m_dat;
1041 objcache_put(mbuf_cache, m);
90775e29 1042 }
4c1e2509 1043 atomic_subtract_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mbufs, 1);
77e294a1
MD
1044 break;
1045 default:
1046 if (!panicstr)
1047 panic("bad mbuf flags %p %08x\n", m, m->m_flags);
1048 break;
b6650ec0 1049 }
984263bc
MD
1050 return (n);
1051}
1052
1053void
b6650ec0 1054m_freem(struct mbuf *m)
984263bc 1055{
90775e29
MD
1056 while (m)
1057 m = m_free(m);
984263bc
MD
1058}
1059
1060/*
df80f2ea 1061 * mbuf utility routines
984263bc
MD
1062 */
1063
1064/*
7b6f875f 1065 * Lesser-used path for M_PREPEND: allocate new mbuf to prepend to chain and
984263bc
MD
1066 * copy junk along.
1067 */
1068struct mbuf *
8a3125c6 1069m_prepend(struct mbuf *m, int len, int how)
984263bc
MD
1070{
1071 struct mbuf *mn;
1072
c3ef87ca
MD
1073 if (m->m_flags & M_PKTHDR)
1074 mn = m_gethdr(how, m->m_type);
1075 else
1076 mn = m_get(how, m->m_type);
7b6f875f 1077 if (mn == NULL) {
984263bc 1078 m_freem(m);
7b6f875f 1079 return (NULL);
984263bc
MD
1080 }
1081 if (m->m_flags & M_PKTHDR)
1082 M_MOVE_PKTHDR(mn, m);
1083 mn->m_next = m;
1084 m = mn;
1085 if (len < MHLEN)
1086 MH_ALIGN(m, len);
1087 m->m_len = len;
1088 return (m);
1089}
1090
1091/*
1092 * Make a copy of an mbuf chain starting "off0" bytes from the beginning,
1093 * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf.
74f1caca 1094 * The wait parameter is a choice of MB_WAIT/MB_DONTWAIT from caller.
984263bc
MD
1095 * Note that the copy is read-only, because clusters are not copied,
1096 * only their reference counts are incremented.
1097 */
984263bc 1098struct mbuf *
8a3125c6 1099m_copym(const struct mbuf *m, int off0, int len, int wait)
984263bc 1100{
1fd87d54
RG
1101 struct mbuf *n, **np;
1102 int off = off0;
984263bc
MD
1103 struct mbuf *top;
1104 int copyhdr = 0;
1105
1106 KASSERT(off >= 0, ("m_copym, negative off %d", off));
1107 KASSERT(len >= 0, ("m_copym, negative len %d", len));
5bd48c1d 1108 if (off == 0 && (m->m_flags & M_PKTHDR))
984263bc
MD
1109 copyhdr = 1;
1110 while (off > 0) {
1111 KASSERT(m != NULL, ("m_copym, offset > size of mbuf chain"));
1112 if (off < m->m_len)
1113 break;
1114 off -= m->m_len;
1115 m = m->m_next;
1116 }
1117 np = &top;
5bd48c1d 1118 top = NULL;
984263bc 1119 while (len > 0) {
7b6f875f 1120 if (m == NULL) {
984263bc
MD
1121 KASSERT(len == M_COPYALL,
1122 ("m_copym, length > size of mbuf chain"));
1123 break;
1124 }
c3ef87ca
MD
1125 /*
1126 * Because we are sharing any cluster attachment below,
1127 * be sure to get an mbuf that does not have a cluster
1128 * associated with it.
1129 */
1130 if (copyhdr)
1131 n = m_gethdr(wait, m->m_type);
1132 else
1133 n = m_get(wait, m->m_type);
984263bc 1134 *np = n;
7b6f875f 1135 if (n == NULL)
984263bc
MD
1136 goto nospace;
1137 if (copyhdr) {
1138 if (!m_dup_pkthdr(n, m, wait))
1139 goto nospace;
1140 if (len == M_COPYALL)
1141 n->m_pkthdr.len -= off0;
1142 else
1143 n->m_pkthdr.len = len;
1144 copyhdr = 0;
1145 }
1146 n->m_len = min(len, m->m_len - off);
1147 if (m->m_flags & M_EXT) {
c3ef87ca 1148 KKASSERT((n->m_flags & M_EXT) == 0);
984263bc 1149 n->m_data = m->m_data + off;
7b6f875f 1150 m->m_ext.ext_ref(m->m_ext.ext_arg);
984263bc 1151 n->m_ext = m->m_ext;
b542cd49 1152 n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER);
7eccf245 1153 } else {
984263bc
MD
1154 bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t),
1155 (unsigned)n->m_len);
7eccf245 1156 }
984263bc
MD
1157 if (len != M_COPYALL)
1158 len -= n->m_len;
1159 off = 0;
1160 m = m->m_next;
1161 np = &n->m_next;
1162 }
7b6f875f 1163 if (top == NULL)
4c1e2509 1164 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1);
984263bc
MD
1165 return (top);
1166nospace:
1167 m_freem(top);
4c1e2509 1168 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1);
7b6f875f 1169 return (NULL);
984263bc
MD
1170}
1171
1172/*
1173 * Copy an entire packet, including header (which must be present).
1174 * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'.
1175 * Note that the copy is read-only, because clusters are not copied,
1176 * only their reference counts are incremented.
1177 * Preserve alignment of the first mbuf so if the creator has left
1178 * some room at the beginning (e.g. for inserting protocol headers)
1179 * the copies also have the room available.
1180 */
1181struct mbuf *
8a3125c6 1182m_copypacket(struct mbuf *m, int how)
984263bc
MD
1183{
1184 struct mbuf *top, *n, *o;
1185
7f3602fe 1186 n = m_gethdr(how, m->m_type);
984263bc
MD
1187 top = n;
1188 if (!n)
1189 goto nospace;
1190
1191 if (!m_dup_pkthdr(n, m, how))
1192 goto nospace;
1193 n->m_len = m->m_len;
1194 if (m->m_flags & M_EXT) {
c3ef87ca 1195 KKASSERT((n->m_flags & M_EXT) == 0);
984263bc 1196 n->m_data = m->m_data;
7b6f875f 1197 m->m_ext.ext_ref(m->m_ext.ext_arg);
984263bc 1198 n->m_ext = m->m_ext;
b542cd49 1199 n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER);
984263bc
MD
1200 } else {
1201 n->m_data = n->m_pktdat + (m->m_data - m->m_pktdat );
1202 bcopy(mtod(m, char *), mtod(n, char *), n->m_len);
1203 }
1204
1205 m = m->m_next;
1206 while (m) {
7b6f875f 1207 o = m_get(how, m->m_type);
984263bc
MD
1208 if (!o)
1209 goto nospace;
1210
1211 n->m_next = o;
1212 n = n->m_next;
1213
1214 n->m_len = m->m_len;
1215 if (m->m_flags & M_EXT) {
c3ef87ca 1216 KKASSERT((n->m_flags & M_EXT) == 0);
984263bc 1217 n->m_data = m->m_data;
7b6f875f 1218 m->m_ext.ext_ref(m->m_ext.ext_arg);
984263bc 1219 n->m_ext = m->m_ext;
b542cd49 1220 n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER);
984263bc
MD
1221 } else {
1222 bcopy(mtod(m, char *), mtod(n, char *), n->m_len);
1223 }
1224
1225 m = m->m_next;
1226 }
1227 return top;
1228nospace:
1229 m_freem(top);
4c1e2509 1230 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1);
7b6f875f 1231 return (NULL);
984263bc
MD
1232}
1233
1234/*
1235 * Copy data from an mbuf chain starting "off" bytes from the beginning,
1236 * continuing for "len" bytes, into the indicated buffer.
1237 */
1238void
8a3125c6 1239m_copydata(const struct mbuf *m, int off, int len, caddr_t cp)
984263bc 1240{
1fd87d54 1241 unsigned count;
984263bc
MD
1242
1243 KASSERT(off >= 0, ("m_copydata, negative off %d", off));
1244 KASSERT(len >= 0, ("m_copydata, negative len %d", len));
1245 while (off > 0) {
1246 KASSERT(m != NULL, ("m_copydata, offset > size of mbuf chain"));
1247 if (off < m->m_len)
1248 break;
1249 off -= m->m_len;
1250 m = m->m_next;
1251 }
1252 while (len > 0) {
1253 KASSERT(m != NULL, ("m_copydata, length > size of mbuf chain"));
1254 count = min(m->m_len - off, len);
1255 bcopy(mtod(m, caddr_t) + off, cp, count);
1256 len -= count;
1257 cp += count;
1258 off = 0;
1259 m = m->m_next;
1260 }
1261}
1262
1263/*
1264 * Copy a packet header mbuf chain into a completely new chain, including
1265 * copying any mbuf clusters. Use this instead of m_copypacket() when
1266 * you need a writable copy of an mbuf chain.
1267 */
1268struct mbuf *
8a3125c6 1269m_dup(struct mbuf *m, int how)
984263bc
MD
1270{
1271 struct mbuf **p, *top = NULL;
1272 int remain, moff, nsize;
1273
1274 /* Sanity check */
1275 if (m == NULL)
50503f0f 1276 return (NULL);
5e2195bf 1277 KASSERT((m->m_flags & M_PKTHDR) != 0, ("%s: !PKTHDR", __func__));
984263bc
MD
1278
1279 /* While there's more data, get a new mbuf, tack it on, and fill it */
1280 remain = m->m_pkthdr.len;
1281 moff = 0;
1282 p = &top;
1283 while (remain > 0 || top == NULL) { /* allow m->m_pkthdr.len == 0 */
1284 struct mbuf *n;
1285
1286 /* Get the next new mbuf */
50503f0f
JH
1287 n = m_getl(remain, how, m->m_type, top == NULL ? M_PKTHDR : 0,
1288 &nsize);
984263bc
MD
1289 if (n == NULL)
1290 goto nospace;
50503f0f 1291 if (top == NULL)
984263bc 1292 if (!m_dup_pkthdr(n, m, how))
50503f0f 1293 goto nospace0;
984263bc
MD
1294
1295 /* Link it into the new chain */
1296 *p = n;
1297 p = &n->m_next;
1298
1299 /* Copy data from original mbuf(s) into new mbuf */
50503f0f 1300 n->m_len = 0;
984263bc
MD
1301 while (n->m_len < nsize && m != NULL) {
1302 int chunk = min(nsize - n->m_len, m->m_len - moff);
1303
1304 bcopy(m->m_data + moff, n->m_data + n->m_len, chunk);
1305 moff += chunk;
1306 n->m_len += chunk;
1307 remain -= chunk;
1308 if (moff == m->m_len) {
1309 m = m->m_next;
1310 moff = 0;
1311 }
1312 }
1313
1314 /* Check correct total mbuf length */
1315 KASSERT((remain > 0 && m != NULL) || (remain == 0 && m == NULL),
50503f0f 1316 ("%s: bogus m_pkthdr.len", __func__));
984263bc
MD
1317 }
1318 return (top);
1319
1320nospace:
1321 m_freem(top);
50503f0f 1322nospace0:
4c1e2509 1323 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1);
50503f0f 1324 return (NULL);
984263bc
MD
1325}
1326
3bf6fec3
MD
1327/*
1328 * Copy the non-packet mbuf data chain into a new set of mbufs, including
1329 * copying any mbuf clusters. This is typically used to realign a data
1330 * chain by nfs_realign().
1331 *
1332 * The original chain is left intact. how should be MB_WAIT or MB_DONTWAIT
1333 * and NULL can be returned if MB_DONTWAIT is passed.
1334 *
1335 * Be careful to use cluster mbufs, a large mbuf chain converted to non
1336 * cluster mbufs can exhaust our supply of mbufs.
1337 */
1338struct mbuf *
1339m_dup_data(struct mbuf *m, int how)
1340{
1341 struct mbuf **p, *n, *top = NULL;
1342 int mlen, moff, chunk, gsize, nsize;
1343
1344 /*
1345 * Degenerate case
1346 */
1347 if (m == NULL)
1348 return (NULL);
1349
1350 /*
1351 * Optimize the mbuf allocation but do not get too carried away.
1352 */
1353 if (m->m_next || m->m_len > MLEN)
1354 gsize = MCLBYTES;
1355 else
1356 gsize = MLEN;
1357
1358 /* Chain control */
1359 p = &top;
1360 n = NULL;
1361 nsize = 0;
1362
1363 /*
1364 * Scan the mbuf chain until nothing is left, the new mbuf chain
1365 * will be allocated on the fly as needed.
1366 */
1367 while (m) {
1368 mlen = m->m_len;
1369 moff = 0;
1370
1371 while (mlen) {
1372 KKASSERT(m->m_type == MT_DATA);
1373 if (n == NULL) {
1374 n = m_getl(gsize, how, MT_DATA, 0, &nsize);
1375 n->m_len = 0;
1376 if (n == NULL)
1377 goto nospace;
1378 *p = n;
1379 p = &n->m_next;
1380 }
1381 chunk = imin(mlen, nsize);
1382 bcopy(m->m_data + moff, n->m_data + n->m_len, chunk);
1383 mlen -= chunk;
1384 moff += chunk;
1385 n->m_len += chunk;
1386 nsize -= chunk;
1387 if (nsize == 0)
1388 n = NULL;
1389 }
1390 m = m->m_next;
1391 }
1392 *p = NULL;
1393 return(top);
1394nospace:
1395 *p = NULL;
1396 m_freem(top);
1397 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1);
1398 return (NULL);
1399}
1400
984263bc
MD
1401/*
1402 * Concatenate mbuf chain n to m.
1403 * Both chains must be of the same type (e.g. MT_DATA).
1404 * Any m_pkthdr is not updated.
1405 */
1406void
8a3125c6 1407m_cat(struct mbuf *m, struct mbuf *n)
984263bc 1408{
50503f0f 1409 m = m_last(m);
984263bc
MD
1410 while (n) {
1411 if (m->m_flags & M_EXT ||
1412 m->m_data + m->m_len + n->m_len >= &m->m_dat[MLEN]) {
1413 /* just join the two chains */
1414 m->m_next = n;
1415 return;
1416 }
1417 /* splat the data from one into the other */
1418 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len,
1419 (u_int)n->m_len);
1420 m->m_len += n->m_len;
1421 n = m_free(n);
1422 }
1423}
1424
1425void
8a3125c6 1426m_adj(struct mbuf *mp, int req_len)
984263bc 1427{
1fd87d54
RG
1428 int len = req_len;
1429 struct mbuf *m;
1430 int count;
984263bc
MD
1431
1432 if ((m = mp) == NULL)
1433 return;
1434 if (len >= 0) {
1435 /*
1436 * Trim from head.
1437 */
1438 while (m != NULL && len > 0) {
1439 if (m->m_len <= len) {
1440 len -= m->m_len;
1441 m->m_len = 0;
1442 m = m->m_next;
1443 } else {
1444 m->m_len -= len;
1445 m->m_data += len;
1446 len = 0;
1447 }
1448 }
1449 m = mp;
1450 if (mp->m_flags & M_PKTHDR)
1451 m->m_pkthdr.len -= (req_len - len);
1452 } else {
1453 /*
1454 * Trim from tail. Scan the mbuf chain,
1455 * calculating its length and finding the last mbuf.
1456 * If the adjustment only affects this mbuf, then just
1457 * adjust and return. Otherwise, rescan and truncate
1458 * after the remaining size.
1459 */
1460 len = -len;
1461 count = 0;
1462 for (;;) {
1463 count += m->m_len;
60233e58 1464 if (m->m_next == NULL)
984263bc
MD
1465 break;
1466 m = m->m_next;
1467 }
1468 if (m->m_len >= len) {
1469 m->m_len -= len;
1470 if (mp->m_flags & M_PKTHDR)
1471 mp->m_pkthdr.len -= len;
1472 return;
1473 }
1474 count -= len;
1475 if (count < 0)
1476 count = 0;
1477 /*
1478 * Correct length for chain is "count".
1479 * Find the mbuf with last data, adjust its length,
1480 * and toss data from remaining mbufs on chain.
1481 */
1482 m = mp;
1483 if (m->m_flags & M_PKTHDR)
1484 m->m_pkthdr.len = count;
1485 for (; m; m = m->m_next) {
1486 if (m->m_len >= count) {
1487 m->m_len = count;
1488 break;
1489 }
1490 count -= m->m_len;
1491 }
1492 while (m->m_next)
1493 (m = m->m_next) ->m_len = 0;
1494 }
1495}
1496
a3768f58
RP
1497/*
1498 * Set the m_data pointer of a newly-allocated mbuf
1499 * to place an object of the specified size at the
1500 * end of the mbuf, longword aligned.
1501 */
1502void
1503m_align(struct mbuf *m, int len)
1504{
1505 int adjust;
1506
1507 if (m->m_flags & M_EXT)
1508 adjust = m->m_ext.ext_size - len;
1509 else if (m->m_flags & M_PKTHDR)
1510 adjust = MHLEN - len;
1511 else
1512 adjust = MLEN - len;
1513 m->m_data += adjust &~ (sizeof(long)-1);
1514}
1515
984263bc 1516/*
7b6f875f 1517 * Rearrange an mbuf chain so that len bytes are contiguous
9e4465af
MD
1518 * and in the data area of an mbuf (so that mtod will work for a structure
1519 * of size len). Returns the resulting mbuf chain on success, frees it and
1520 * returns null on failure. If there is room, it will add up to
1521 * max_protohdr-len extra bytes to the contiguous region in an attempt to
1522 * avoid being called next time.
984263bc 1523 */
984263bc 1524struct mbuf *
8a3125c6 1525m_pullup(struct mbuf *n, int len)
984263bc 1526{
1fd87d54
RG
1527 struct mbuf *m;
1528 int count;
984263bc
MD
1529 int space;
1530
1531 /*
1532 * If first mbuf has no cluster, and has room for len bytes
1533 * without shifting current data, pullup into it,
1534 * otherwise allocate a new mbuf to prepend to the chain.
1535 */
7b6f875f
JH
1536 if (!(n->m_flags & M_EXT) &&
1537 n->m_data + len < &n->m_dat[MLEN] &&
1538 n->m_next) {
984263bc
MD
1539 if (n->m_len >= len)
1540 return (n);
1541 m = n;
1542 n = n->m_next;
1543 len -= m->m_len;
1544 } else {
1545 if (len > MHLEN)
1546 goto bad;
c3ef87ca
MD
1547 if (n->m_flags & M_PKTHDR)
1548 m = m_gethdr(MB_DONTWAIT, n->m_type);
1549 else
1550 m = m_get(MB_DONTWAIT, n->m_type);
7b6f875f 1551 if (m == NULL)
984263bc
MD
1552 goto bad;
1553 m->m_len = 0;
1554 if (n->m_flags & M_PKTHDR)
1555 M_MOVE_PKTHDR(m, n);
1556 }
1557 space = &m->m_dat[MLEN] - (m->m_data + m->m_len);
1558 do {
1559 count = min(min(max(len, max_protohdr), space), n->m_len);
1560 bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len,
1561 (unsigned)count);
1562 len -= count;
1563 m->m_len += count;
1564 n->m_len -= count;
1565 space -= count;
1566 if (n->m_len)
1567 n->m_data += count;
1568 else
1569 n = m_free(n);
1570 } while (len > 0 && n);
1571 if (len > 0) {
7b6f875f 1572 m_free(m);
984263bc
MD
1573 goto bad;
1574 }
1575 m->m_next = n;
1576 return (m);
1577bad:
1578 m_freem(n);
4c1e2509 1579 atomic_add_long_nonlocked(&mbstat[mycpu->gd_cpuid].m_mcfail, 1);
7b6f875f 1580 return (NULL);
984263bc
MD
1581}
1582
1583/*
1584 * Partition an mbuf chain in two pieces, returning the tail --
1585 * all but the first len0 bytes. In case of failure, it returns NULL and
1586 * attempts to restore the chain to its original state.
1587 *
1588 * Note that the resulting mbufs might be read-only, because the new
1589 * mbuf can end up sharing an mbuf cluster with the original mbuf if
1590 * the "breaking point" happens to lie within a cluster mbuf. Use the
1591 * M_WRITABLE() macro to check for this case.
1592 */
1593struct mbuf *
8a3125c6 1594m_split(struct mbuf *m0, int len0, int wait)
984263bc 1595{
1fd87d54 1596 struct mbuf *m, *n;
984263bc
MD
1597 unsigned len = len0, remain;
1598
1599 for (m = m0; m && len > m->m_len; m = m->m_next)
1600 len -= m->m_len;
7b6f875f
JH
1601 if (m == NULL)
1602 return (NULL);
984263bc
MD
1603 remain = m->m_len - len;
1604 if (m0->m_flags & M_PKTHDR) {
7b6f875f
JH
1605 n = m_gethdr(wait, m0->m_type);
1606 if (n == NULL)
1607 return (NULL);
984263bc
MD
1608 n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif;
1609 n->m_pkthdr.len = m0->m_pkthdr.len - len0;
1610 m0->m_pkthdr.len = len0;
1611 if (m->m_flags & M_EXT)
1612 goto extpacket;
1613 if (remain > MHLEN) {
1614 /* m can't be the lead packet */
1615 MH_ALIGN(n, 0);
1616 n->m_next = m_split(m, len, wait);
7b6f875f
JH
1617 if (n->m_next == NULL) {
1618 m_free(n);
1619 return (NULL);
984263bc
MD
1620 } else {
1621 n->m_len = 0;
1622 return (n);
1623 }
1624 } else
1625 MH_ALIGN(n, remain);
1626 } else if (remain == 0) {
1627 n = m->m_next;
1628 m->m_next = 0;
1629 return (n);
1630 } else {
7b6f875f
JH
1631 n = m_get(wait, m->m_type);
1632 if (n == NULL)
1633 return (NULL);
984263bc
MD
1634 M_ALIGN(n, remain);
1635 }
1636extpacket:
1637 if (m->m_flags & M_EXT) {
c3ef87ca 1638 KKASSERT((n->m_flags & M_EXT) == 0);
984263bc 1639 n->m_data = m->m_data + len;
7b6f875f 1640 m->m_ext.ext_ref(m->m_ext.ext_arg);
7eccf245 1641 n->m_ext = m->m_ext;
b542cd49 1642 n->m_flags |= m->m_flags & (M_EXT | M_EXT_CLUSTER);
984263bc
MD
1643 } else {
1644 bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain);
1645 }
1646 n->m_len = remain;
1647 m->m_len = len;
1648 n->m_next = m->m_next;
1649 m->m_next = 0;
1650 return (n);
1651}
50503f0f 1652
984263bc
MD
1653/*
1654 * Routine to copy from device local memory into mbufs.
50503f0f 1655 * Note: "offset" is ill-defined and always called as 0, so ignore it.
984263bc
MD
1656 */
1657struct mbuf *
50503f0f
JH
1658m_devget(char *buf, int len, int offset, struct ifnet *ifp,
1659 void (*copy)(volatile const void *from, volatile void *to, size_t length))
984263bc 1660{
50503f0f
JH
1661 struct mbuf *m, *mfirst = NULL, **mtail;
1662 int nsize, flags;
1663
1664 if (copy == NULL)
1665 copy = bcopy;
1666 mtail = &mfirst;
1667 flags = M_PKTHDR;
1668
1669 while (len > 0) {
1670 m = m_getl(len, MB_DONTWAIT, MT_DATA, flags, &nsize);
1671 if (m == NULL) {
1672 m_freem(mfirst);
1673 return (NULL);
984263bc 1674 }
50503f0f
JH
1675 m->m_len = min(len, nsize);
1676
1677 if (flags & M_PKTHDR) {
1678 if (len + max_linkhdr <= nsize)
1679 m->m_data += max_linkhdr;
1680 m->m_pkthdr.rcvif = ifp;
1681 m->m_pkthdr.len = len;
1682 flags = 0;
984263bc 1683 }
50503f0f
JH
1684
1685 copy(buf, m->m_data, (unsigned)m->m_len);
1686 buf += m->m_len;
1687 len -= m->m_len;
1688 *mtail = m;
1689 mtail = &m->m_next;
984263bc 1690 }
50503f0f
JH
1691
1692 return (mfirst);
984263bc
MD
1693}
1694
cf12ba3c
SZ
1695/*
1696 * Routine to pad mbuf to the specified length 'padto'.
1697 */
1698int
1699m_devpad(struct mbuf *m, int padto)
1700{
1701 struct mbuf *last = NULL;
1702 int padlen;
1703
1704 if (padto <= m->m_pkthdr.len)
1705 return 0;
1706
1707 padlen = padto - m->m_pkthdr.len;
1708
1709 /* if there's only the packet-header and we can pad there, use it. */
1710 if (m->m_pkthdr.len == m->m_len && M_TRAILINGSPACE(m) >= padlen) {
1711 last = m;
1712 } else {
1713 /*
1714 * Walk packet chain to find last mbuf. We will either
1715 * pad there, or append a new mbuf and pad it
1716 */
1717 for (last = m; last->m_next != NULL; last = last->m_next)
1718 ; /* EMPTY */
1719
1720 /* `last' now points to last in chain. */
1721 if (M_TRAILINGSPACE(last) < padlen) {
1722 struct mbuf *n;
1723
1724 /* Allocate new empty mbuf, pad it. Compact later. */
1725 MGET(n, MB_DONTWAIT, MT_DATA);
1726 if (n == NULL)
1727 return ENOBUFS;
1728 n->m_len = 0;
1729 last->m_next = n;
1730 last = n;
1731 }
1732 }
1733 KKASSERT(M_TRAILINGSPACE(last) >= padlen);
1734 KKASSERT(M_WRITABLE(last));
1735
1736 /* Now zero the pad area */
1737 bzero(mtod(last, char *) + last->m_len, padlen);
1738 last->m_len += padlen;
1739 m->m_pkthdr.len += padlen;
1740 return 0;
1741}
1742
984263bc
MD
1743/*
1744 * Copy data from a buffer back into the indicated mbuf chain,
1745 * starting "off" bytes from the beginning, extending the mbuf
1746 * chain if necessary.
1747 */
1748void
8a3125c6 1749m_copyback(struct mbuf *m0, int off, int len, caddr_t cp)
984263bc 1750{
1fd87d54
RG
1751 int mlen;
1752 struct mbuf *m = m0, *n;
984263bc
MD
1753 int totlen = 0;
1754
7b6f875f 1755 if (m0 == NULL)
984263bc
MD
1756 return;
1757 while (off > (mlen = m->m_len)) {
1758 off -= mlen;
1759 totlen += mlen;
7b6f875f 1760 if (m->m_next == NULL) {
74f1caca 1761 n = m_getclr(MB_DONTWAIT, m->m_type);
7b6f875f 1762 if (n == NULL)
984263bc
MD
1763 goto out;
1764 n->m_len = min(MLEN, len + off);
1765 m->m_next = n;
1766 }
1767 m = m->m_next;
1768 }
1769 while (len > 0) {
1770 mlen = min (m->m_len - off, len);
1771 bcopy(cp, off + mtod(m, caddr_t), (unsigned)mlen);
1772 cp += mlen;
1773 len -= mlen;
1774 mlen += off;
1775 off = 0;
1776 totlen += mlen;
1777 if (len == 0)
1778 break;
7b6f875f 1779 if (m->m_next == NULL) {
74f1caca 1780 n = m_get(MB_DONTWAIT, m->m_type);
7b6f875f 1781 if (n == NULL)
984263bc
MD
1782 break;
1783 n->m_len = min(MLEN, len);
1784 m->m_next = n;
1785 }
1786 m = m->m_next;
1787 }
1788out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen))
1789 m->m_pkthdr.len = totlen;
1790}
1791
bf2cc98c
RP
1792/*
1793 * Append the specified data to the indicated mbuf chain,
1794 * Extend the mbuf chain if the new data does not fit in
1795 * existing space.
1796 *
1797 * Return 1 if able to complete the job; otherwise 0.
1798 */
1799int
1800m_append(struct mbuf *m0, int len, c_caddr_t cp)
1801{
1802 struct mbuf *m, *n;
1803 int remainder, space;
1804
1805 for (m = m0; m->m_next != NULL; m = m->m_next)
1806 ;
1807 remainder = len;
1808 space = M_TRAILINGSPACE(m);
1809 if (space > 0) {
1810 /*
1811 * Copy into available space.
1812 */
1813 if (space > remainder)
1814 space = remainder;
1815 bcopy(cp, mtod(m, caddr_t) + m->m_len, space);
1816 m->m_len += space;
1817 cp += space, remainder -= space;
1818 }
1819 while (remainder > 0) {
1820 /*
1821 * Allocate a new mbuf; could check space
1822 * and allocate a cluster instead.
1823 */
1824 n = m_get(MB_DONTWAIT, m->m_type);
1825 if (n == NULL)
1826 break;
1827 n->m_len = min(MLEN, remainder);
1828 bcopy(cp, mtod(n, caddr_t), n->m_len);
1829 cp += n->m_len, remainder -= n->m_len;
1830 m->m_next = n;
1831 m = n;
1832 }
1833 if (m0->m_flags & M_PKTHDR)
1834 m0->m_pkthdr.len += len - remainder;
1835 return (remainder == 0);
1836}
1837
920c9f10
AH
1838/*
1839 * Apply function f to the data in an mbuf chain starting "off" bytes from
1840 * the beginning, continuing for "len" bytes.
1841 */
1842int
1843m_apply(struct mbuf *m, int off, int len,
1844 int (*f)(void *, void *, u_int), void *arg)
1845{
1846 u_int count;
1847 int rval;
1848
1849 KASSERT(off >= 0, ("m_apply, negative off %d", off));
1850 KASSERT(len >= 0, ("m_apply, negative len %d", len));
1851 while (off > 0) {
1852 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain"));
1853 if (off < m->m_len)
1854 break;
1855 off -= m->m_len;
1856 m = m->m_next;
1857 }
1858 while (len > 0) {
1859 KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain"));
1860 count = min(m->m_len - off, len);
1861 rval = (*f)(arg, mtod(m, caddr_t) + off, count);
1862 if (rval)
1863 return (rval);
1864 len -= count;
1865 off = 0;
1866 m = m->m_next;
1867 }
1868 return (0);
1869}
1870
1871/*
1872 * Return a pointer to mbuf/offset of location in mbuf chain.
1873 */
1874struct mbuf *
1875m_getptr(struct mbuf *m, int loc, int *off)
1876{
1877
1878 while (loc >= 0) {
1879 /* Normal end of search. */
1880 if (m->m_len > loc) {
1881 *off = loc;
1882 return (m);
1883 } else {
1884 loc -= m->m_len;
1885 if (m->m_next == NULL) {
1886 if (loc == 0) {
1887 /* Point at the end of valid data. */
1888 *off = m->m_len;
1889 return (m);
1890 }
1891 return (NULL);
1892 }
1893 m = m->m_next;
1894 }
1895 }
1896 return (NULL);
1897}
1898
984263bc
MD
1899void
1900m_print(const struct mbuf *m)
1901{
1902 int len;
1903 const struct mbuf *m2;
1904
1905 len = m->m_pkthdr.len;
1906 m2 = m;
1907 while (len) {
6ea70f76 1908 kprintf("%p %*D\n", m2, m2->m_len, (u_char *)m2->m_data, "-");
984263bc
MD
1909 len -= m2->m_len;
1910 m2 = m2->m_next;
1911 }
1912 return;
1913}
1914
1915/*
1916 * "Move" mbuf pkthdr from "from" to "to".
1917 * "from" must have M_PKTHDR set, and "to" must be empty.
1918 */
1919void
1920m_move_pkthdr(struct mbuf *to, struct mbuf *from)
1921{
e0d05288 1922 KASSERT((to->m_flags & M_PKTHDR), ("m_move_pkthdr: not packet header"));
984263bc 1923
77e294a1 1924 to->m_flags |= from->m_flags & M_COPYFLAGS;
984263bc
MD
1925 to->m_pkthdr = from->m_pkthdr; /* especially tags */
1926 SLIST_INIT(&from->m_pkthdr.tags); /* purge tags from src */
984263bc
MD
1927}
1928
1929/*
1930 * Duplicate "from"'s mbuf pkthdr in "to".
1931 * "from" must have M_PKTHDR set, and "to" must be empty.
1932 * In particular, this does a deep copy of the packet tags.
1933 */
1934int
f15db79e 1935m_dup_pkthdr(struct mbuf *to, const struct mbuf *from, int how)
984263bc 1936{
7f3602fe
JH
1937 KASSERT((to->m_flags & M_PKTHDR), ("m_dup_pkthdr: not packet header"));
1938
4bac35fc 1939 to->m_flags = (from->m_flags & M_COPYFLAGS) |
c4da22e4 1940 (to->m_flags & ~M_COPYFLAGS);
984263bc
MD
1941 to->m_pkthdr = from->m_pkthdr;
1942 SLIST_INIT(&to->m_pkthdr.tags);
1943 return (m_tag_copy_chain(to, from, how));
1944}
1945
1946/*
1947 * Defragment a mbuf chain, returning the shortest possible
1948 * chain of mbufs and clusters. If allocation fails and
1949 * this cannot be completed, NULL will be returned, but
1950 * the passed in chain will be unchanged. Upon success,
1951 * the original chain will be freed, and the new chain
1952 * will be returned.
1953 *
1954 * If a non-packet header is passed in, the original
1955 * mbuf (chain?) will be returned unharmed.
c8f5127a
JS
1956 *
1957 * m_defrag_nofree doesn't free the passed in mbuf.
984263bc
MD
1958 */
1959struct mbuf *
1960m_defrag(struct mbuf *m0, int how)
c8f5127a
JS
1961{
1962 struct mbuf *m_new;
1963
1964 if ((m_new = m_defrag_nofree(m0, how)) == NULL)
1965 return (NULL);
1966 if (m_new != m0)
1967 m_freem(m0);
1968 return (m_new);
1969}
1970
1971struct mbuf *
1972m_defrag_nofree(struct mbuf *m0, int how)
984263bc
MD
1973{
1974 struct mbuf *m_new = NULL, *m_final = NULL;
61721e90 1975 int progress = 0, length, nsize;
984263bc
MD
1976
1977 if (!(m0->m_flags & M_PKTHDR))
1978 return (m0);
1979
1980#ifdef MBUF_STRESS_TEST
1981 if (m_defragrandomfailures) {
0ced1954 1982 int temp = karc4random() & 0xff;
984263bc
MD
1983 if (temp == 0xba)
1984 goto nospace;
1985 }
1986#endif
1987
61721e90 1988 m_final = m_getl(m0->m_pkthdr.len, how, MT_DATA, M_PKTHDR, &nsize);
984263bc
MD
1989 if (m_final == NULL)
1990 goto nospace;
61721e90 1991 m_final->m_len = 0; /* in case m0->m_pkthdr.len is zero */
984263bc 1992
3641b7ca 1993 if (m_dup_pkthdr(m_final, m0, how) == 0)
984263bc
MD
1994 goto nospace;
1995
1996 m_new = m_final;
1997
1998 while (progress < m0->m_pkthdr.len) {
1999 length = m0->m_pkthdr.len - progress;
2000 if (length > MCLBYTES)
2001 length = MCLBYTES;
2002
2003 if (m_new == NULL) {
61721e90 2004 m_new = m_getl(length, how, MT_DATA, 0, &nsize);
984263bc
MD
2005 if (m_new == NULL)
2006 goto nospace;
2007 }
2008
2009 m_copydata(m0, progress, length, mtod(m_new, caddr_t));
2010 progress += length;
2011 m_new->m_len = length;
2012 if (m_new != m_final)
2013 m_cat(m_final, m_new);
2014 m_new = NULL;
2015 }
2016 if (m0->m_next == NULL)
2017 m_defraguseless++;
984263bc 2018 m_defragpackets++;
c8f5127a
JS
2019 m_defragbytes += m_final->m_pkthdr.len;
2020 return (m_final);
984263bc
MD
2021nospace:
2022 m_defragfailure++;
2023 if (m_new)
2024 m_free(m_new);
61721e90 2025 m_freem(m_final);
984263bc
MD
2026 return (NULL);
2027}
0c33f36d
JH
2028
2029/*
2030 * Move data from uio into mbufs.
0c33f36d
JH
2031 */
2032struct mbuf *
e12241e1 2033m_uiomove(struct uio *uio)
0c33f36d 2034{
0c33f36d 2035 struct mbuf *m; /* current working mbuf */
e12241e1
JH
2036 struct mbuf *head = NULL; /* result mbuf chain */
2037 struct mbuf **mp = &head;
e54488bb
MD
2038 int flags = M_PKTHDR;
2039 int nsize;
2040 int error;
2041 int resid;
0c33f36d 2042
0c33f36d 2043 do {
e54488bb
MD
2044 if (uio->uio_resid > INT_MAX)
2045 resid = INT_MAX;
2046 else
2047 resid = (int)uio->uio_resid;
e12241e1 2048 m = m_getl(resid, MB_WAIT, MT_DATA, flags, &nsize);
61721e90
JH
2049 if (flags) {
2050 m->m_pkthdr.len = 0;
2051 /* Leave room for protocol headers. */
2052 if (resid < MHLEN)
2053 MH_ALIGN(m, resid);
2054 flags = 0;
0c33f36d 2055 }
e54488bb 2056 m->m_len = imin(nsize, resid);
61721e90 2057 error = uiomove(mtod(m, caddr_t), m->m_len, uio);
0c33f36d
JH
2058 if (error) {
2059 m_free(m);
2060 goto failed;
2061 }
0c33f36d
JH
2062 *mp = m;
2063 mp = &m->m_next;
61721e90 2064 head->m_pkthdr.len += m->m_len;
e54488bb 2065 } while (uio->uio_resid > 0);
0c33f36d
JH
2066
2067 return (head);
2068
2069failed:
61721e90 2070 m_freem(head);
0c33f36d
JH
2071 return (NULL);
2072}
df80f2ea 2073
50503f0f
JH
2074struct mbuf *
2075m_last(struct mbuf *m)
2076{
2077 while (m->m_next)
2078 m = m->m_next;
2079 return (m);
2080}
2081
df80f2ea
JH
2082/*
2083 * Return the number of bytes in an mbuf chain.
2084 * If lastm is not NULL, also return the last mbuf.
2085 */
2086u_int
2087m_lengthm(struct mbuf *m, struct mbuf **lastm)
2088{
2089 u_int len = 0;
2090 struct mbuf *prev = m;
2091
2092 while (m) {
2093 len += m->m_len;
2094 prev = m;
2095 m = m->m_next;
2096 }
2097 if (lastm != NULL)
2098 *lastm = prev;
2099 return (len);
2100}
2101
2102/*
2103 * Like m_lengthm(), except also keep track of mbuf usage.
2104 */
2105u_int
2106m_countm(struct mbuf *m, struct mbuf **lastm, u_int *pmbcnt)
2107{
2108 u_int len = 0, mbcnt = 0;
2109 struct mbuf *prev = m;
2110
2111 while (m) {
2112 len += m->m_len;
2113 mbcnt += MSIZE;
2114 if (m->m_flags & M_EXT)
2115 mbcnt += m->m_ext.ext_size;
2116 prev = m;
2117 m = m->m_next;
2118 }
2119 if (lastm != NULL)
2120 *lastm = prev;
2121 *pmbcnt = mbcnt;
2122 return (len);
2123}