Annotation of src/sys/kern/uipc_mbuf.c, Revision 1.105
1.105 ! yamt 1: /* $NetBSD$ */
1.42 thorpej 2:
3: /*-
1.53 thorpej 4: * Copyright (c) 1999, 2001 The NetBSD Foundation, Inc.
1.42 thorpej 5: * All rights reserved.
6: *
7: * This code is derived from software contributed to The NetBSD Foundation
8: * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9: * NASA Ames Research Center.
10: *
11: * Redistribution and use in source and binary forms, with or without
12: * modification, are permitted provided that the following conditions
13: * are met:
14: * 1. Redistributions of source code must retain the above copyright
15: * notice, this list of conditions and the following disclaimer.
16: * 2. Redistributions in binary form must reproduce the above copyright
17: * notice, this list of conditions and the following disclaimer in the
18: * documentation and/or other materials provided with the distribution.
19: * 3. All advertising materials mentioning features or use of this software
20: * must display the following acknowledgement:
21: * This product includes software developed by the NetBSD
22: * Foundation, Inc. and its contributors.
23: * 4. Neither the name of The NetBSD Foundation nor the names of its
24: * contributors may be used to endorse or promote products derived
25: * from this software without specific prior written permission.
26: *
27: * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
28: * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
29: * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
30: * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
31: * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
32: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
33: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
34: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
35: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
36: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
37: * POSSIBILITY OF SUCH DAMAGE.
38: */
1.10 cgd 39:
1.1 cgd 40: /*
1.9 mycroft 41: * Copyright (c) 1982, 1986, 1988, 1991, 1993
42: * The Regents of the University of California. All rights reserved.
1.1 cgd 43: *
44: * Redistribution and use in source and binary forms, with or without
45: * modification, are permitted provided that the following conditions
46: * are met:
47: * 1. Redistributions of source code must retain the above copyright
48: * notice, this list of conditions and the following disclaimer.
49: * 2. Redistributions in binary form must reproduce the above copyright
50: * notice, this list of conditions and the following disclaimer in the
51: * documentation and/or other materials provided with the distribution.
1.70 agc 52: * 3. Neither the name of the University nor the names of its contributors
1.1 cgd 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: *
1.26 fvdl 68: * @(#)uipc_mbuf.c 8.4 (Berkeley) 2/14/95
1.1 cgd 69: */
1.56 lukem 70:
71: #include <sys/cdefs.h>
1.105 ! yamt 72: __KERNEL_RCSID(0, "$NetBSD$");
1.69 martin 73:
74: #include "opt_mbuftrace.h"
1.105 ! yamt 75: #include "opt_ddb.h"
1.24 mrg 76:
1.6 mycroft 77: #include <sys/param.h>
78: #include <sys/systm.h>
79: #include <sys/proc.h>
80: #include <sys/malloc.h>
1.1 cgd 81: #define MBTYPES
1.6 mycroft 82: #include <sys/mbuf.h>
83: #include <sys/kernel.h>
84: #include <sys/syslog.h>
85: #include <sys/domain.h>
86: #include <sys/protosw.h>
1.28 thorpej 87: #include <sys/pool.h>
1.27 matt 88: #include <sys/socket.h>
1.55 simonb 89: #include <sys/sysctl.h>
90:
1.27 matt 91: #include <net/if.h>
1.14 christos 92:
1.65 thorpej 93: #include <uvm/uvm.h>
1.23 mrg 94:
1.42 thorpej 95:
1.28 thorpej 96: struct pool mbpool; /* mbuf pool */
97: struct pool mclpool; /* mbuf cluster pool */
98:
1.53 thorpej 99: struct pool_cache mbpool_cache;
100: struct pool_cache mclpool_cache;
101:
1.18 thorpej 102: struct mbstat mbstat;
103: int max_linkhdr;
104: int max_protohdr;
105: int max_hdr;
106: int max_datalen;
107:
1.65 thorpej 108: static int mb_ctor(void *, void *, int);
109:
1.103 thorpej 110: static void *mclpool_alloc(struct pool *, int);
111: static void mclpool_release(struct pool *, void *);
1.58 thorpej 112:
1.103 thorpej 113: static struct pool_allocator mclpool_allocator = {
1.58 thorpej 114: mclpool_alloc, mclpool_release, 0,
115: };
116:
1.79 junyoung 117: static struct mbuf *m_copym0(struct mbuf *, int, int, int, int);
1.85 yamt 118: static struct mbuf *m_split0(struct mbuf *, int, int, int);
1.86 yamt 119: static int m_copyback0(struct mbuf **, int, int, const void *, int, int);
1.85 yamt 120:
121: /* flags for m_copyback0 */
122: #define M_COPYBACK0_COPYBACK 0x0001 /* copyback from cp */
123: #define M_COPYBACK0_PRESERVE 0x0002 /* preserve original data */
124: #define M_COPYBACK0_COW 0x0004 /* do copy-on-write */
125: #define M_COPYBACK0_EXTEND 0x0008 /* extend chain */
1.28 thorpej 126:
1.103 thorpej 127: static const char mclpool_warnmsg[] =
1.42 thorpej 128: "WARNING: mclpool limit reached; increase NMBCLUSTERS";
1.63 thorpej 129:
130: MALLOC_DEFINE(M_MBUF, "mbuf", "mbuf");
1.42 thorpej 131:
1.64 matt 132: #ifdef MBUFTRACE
133: struct mownerhead mowners = LIST_HEAD_INITIALIZER(mowners);
134: struct mowner unknown_mowners[] = {
135: { "unknown", "free" },
136: { "unknown", "data" },
137: { "unknown", "header" },
138: { "unknown", "soname" },
139: { "unknown", "soopts" },
140: { "unknown", "ftable" },
141: { "unknown", "control" },
142: { "unknown", "oobdata" },
143: };
144: struct mowner revoked_mowner = { "revoked", "" };
145: #endif
146:
1.28 thorpej 147: /*
1.68 simonb 148: * Initialize the mbuf allocator.
1.28 thorpej 149: */
1.4 jtc 150: void
1.62 thorpej 151: mbinit(void)
1.1 cgd 152: {
1.65 thorpej 153:
154: KASSERT(sizeof(struct _m_ext) <= MHLEN);
1.67 simonb 155: KASSERT(sizeof(struct mbuf) == MSIZE);
1.65 thorpej 156:
1.58 thorpej 157: pool_init(&mbpool, msize, 0, 0, 0, "mbpl", NULL);
158: pool_init(&mclpool, mclbytes, 0, 0, 0, "mclpl", &mclpool_allocator);
1.53 thorpej 159:
1.59 thorpej 160: pool_set_drain_hook(&mbpool, m_reclaim, NULL);
161: pool_set_drain_hook(&mclpool, m_reclaim, NULL);
162:
1.65 thorpej 163: pool_cache_init(&mbpool_cache, &mbpool, mb_ctor, NULL, NULL);
1.53 thorpej 164: pool_cache_init(&mclpool_cache, &mclpool, NULL, NULL, NULL);
1.37 thorpej 165:
166: /*
1.39 thorpej 167: * Set the hard limit on the mclpool to the number of
168: * mbuf clusters the kernel is to support. Log the limit
169: * reached message max once a minute.
170: */
1.42 thorpej 171: pool_sethardlimit(&mclpool, nmbclusters, mclpool_warnmsg, 60);
172:
1.39 thorpej 173: /*
1.42 thorpej 174: * Set a low water mark for both mbufs and clusters. This should
175: * help ensure that they can be allocated in a memory starvation
176: * situation. This is important for e.g. diskless systems which
177: * must allocate mbufs in order for the pagedaemon to clean pages.
1.37 thorpej 178: */
1.42 thorpej 179: pool_setlowat(&mbpool, mblowat);
180: pool_setlowat(&mclpool, mcllowat);
1.64 matt 181:
182: #ifdef MBUFTRACE
183: {
184: /*
185: * Attach the unknown mowners.
186: */
187: int i;
188: MOWNER_ATTACH(&revoked_mowner);
189: for (i = sizeof(unknown_mowners)/sizeof(unknown_mowners[0]);
190: i-- > 0; )
191: MOWNER_ATTACH(&unknown_mowners[i]);
192: }
193: #endif
1.42 thorpej 194: }
195:
1.75 atatat 196: /*
197: * sysctl helper routine for the kern.mbuf subtree. nmbclusters may
198: * or may not be writable, and mblowat and mcllowat need range
199: * checking and pool tweaking after being reset.
200: */
201: static int
202: sysctl_kern_mbuf(SYSCTLFN_ARGS)
1.42 thorpej 203: {
204: int error, newval;
1.75 atatat 205: struct sysctlnode node;
1.42 thorpej 206:
1.75 atatat 207: node = *rnode;
208: node.sysctl_data = &newval;
209: switch (rnode->sysctl_num) {
1.42 thorpej 210: case MBUF_NMBCLUSTERS:
1.76 atatat 211: if (mb_map != NULL) {
1.80 atatat 212: node.sysctl_flags &= ~CTLFLAG_READWRITE;
213: node.sysctl_flags |= CTLFLAG_READONLY;
1.75 atatat 214: }
215: /* FALLTHROUGH */
1.42 thorpej 216: case MBUF_MBLOWAT:
217: case MBUF_MCLLOWAT:
1.75 atatat 218: newval = *(int*)rnode->sysctl_data;
219: break;
220: default:
221: return (EOPNOTSUPP);
222: }
223:
224: error = sysctl_lookup(SYSCTLFN_CALL(&node));
225: if (error || newp == NULL)
1.42 thorpej 226: return (error);
1.75 atatat 227: if (newval < 0)
228: return (EINVAL);
229:
230: switch (node.sysctl_num) {
231: case MBUF_NMBCLUSTERS:
232: if (newval < nmbclusters)
233: return (EINVAL);
234: nmbclusters = newval;
235: pool_sethardlimit(&mclpool, nmbclusters, mclpool_warnmsg, 60);
236: break;
237: case MBUF_MBLOWAT:
238: mblowat = newval;
1.76 atatat 239: pool_setlowat(&mbpool, mblowat);
1.75 atatat 240: break;
241: case MBUF_MCLLOWAT:
1.76 atatat 242: mcllowat = newval;
243: pool_setlowat(&mclpool, mcllowat);
1.75 atatat 244: break;
245: }
246:
247: return (0);
248: }
249:
1.64 matt 250: #ifdef MBUFTRACE
1.75 atatat 251: static int
252: sysctl_kern_mbuf_mowners(SYSCTLFN_ARGS)
253: {
254: struct mowner *mo;
255: size_t len = 0;
256: int error = 0;
257:
258: if (namelen != 0)
259: return (EINVAL);
260: if (newp != NULL)
261: return (EPERM);
262:
263: LIST_FOREACH(mo, &mowners, mo_link) {
264: if (oldp != NULL) {
265: if (*oldlenp - len < sizeof(*mo)) {
266: error = ENOMEM;
267: break;
268: }
269: error = copyout(mo, (caddr_t) oldp + len,
1.64 matt 270: sizeof(*mo));
1.75 atatat 271: if (error)
272: break;
1.64 matt 273: }
1.75 atatat 274: len += sizeof(*mo);
275: }
276:
277: if (error == 0)
1.64 matt 278: *oldlenp = len;
1.75 atatat 279:
280: return (error);
281: }
282: #endif /* MBUFTRACE */
283:
284: SYSCTL_SETUP(sysctl_kern_mbuf_setup, "sysctl kern.mbuf subtree setup")
285: {
286:
1.80 atatat 287: sysctl_createv(clog, 0, NULL, NULL,
288: CTLFLAG_PERMANENT,
1.75 atatat 289: CTLTYPE_NODE, "kern", NULL,
290: NULL, 0, NULL, 0,
291: CTL_KERN, CTL_EOL);
1.80 atatat 292: sysctl_createv(clog, 0, NULL, NULL,
293: CTLFLAG_PERMANENT,
1.82 atatat 294: CTLTYPE_NODE, "mbuf",
295: SYSCTL_DESCR("mbuf control variables"),
1.75 atatat 296: NULL, 0, NULL, 0,
297: CTL_KERN, KERN_MBUF, CTL_EOL);
298:
1.80 atatat 299: sysctl_createv(clog, 0, NULL, NULL,
300: CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
1.82 atatat 301: CTLTYPE_INT, "msize",
302: SYSCTL_DESCR("mbuf base size"),
1.75 atatat 303: NULL, msize, NULL, 0,
304: CTL_KERN, KERN_MBUF, MBUF_MSIZE, CTL_EOL);
1.80 atatat 305: sysctl_createv(clog, 0, NULL, NULL,
306: CTLFLAG_PERMANENT|CTLFLAG_IMMEDIATE,
1.82 atatat 307: CTLTYPE_INT, "mclbytes",
308: SYSCTL_DESCR("mbuf cluster size"),
1.75 atatat 309: NULL, mclbytes, NULL, 0,
310: CTL_KERN, KERN_MBUF, MBUF_MCLBYTES, CTL_EOL);
1.80 atatat 311: sysctl_createv(clog, 0, NULL, NULL,
312: CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1.82 atatat 313: CTLTYPE_INT, "nmbclusters",
314: SYSCTL_DESCR("Limit on the number of mbuf clusters"),
1.75 atatat 315: sysctl_kern_mbuf, 0, &nmbclusters, 0,
316: CTL_KERN, KERN_MBUF, MBUF_NMBCLUSTERS, CTL_EOL);
1.80 atatat 317: sysctl_createv(clog, 0, NULL, NULL,
318: CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1.82 atatat 319: CTLTYPE_INT, "mblowat",
320: SYSCTL_DESCR("mbuf low water mark"),
1.75 atatat 321: sysctl_kern_mbuf, 0, &mblowat, 0,
322: CTL_KERN, KERN_MBUF, MBUF_MBLOWAT, CTL_EOL);
1.80 atatat 323: sysctl_createv(clog, 0, NULL, NULL,
324: CTLFLAG_PERMANENT|CTLFLAG_READWRITE,
1.82 atatat 325: CTLTYPE_INT, "mcllowat",
326: SYSCTL_DESCR("mbuf cluster low water mark"),
1.75 atatat 327: sysctl_kern_mbuf, 0, &mcllowat, 0,
328: CTL_KERN, KERN_MBUF, MBUF_MCLLOWAT, CTL_EOL);
1.80 atatat 329: sysctl_createv(clog, 0, NULL, NULL,
330: CTLFLAG_PERMANENT,
1.82 atatat 331: CTLTYPE_STRUCT, "stats",
332: SYSCTL_DESCR("mbuf allocation statistics"),
1.75 atatat 333: NULL, 0, &mbstat, sizeof(mbstat),
334: CTL_KERN, KERN_MBUF, MBUF_STATS, CTL_EOL);
335: #ifdef MBUFTRACE
1.80 atatat 336: sysctl_createv(clog, 0, NULL, NULL,
337: CTLFLAG_PERMANENT,
1.82 atatat 338: CTLTYPE_STRUCT, "mowners",
339: SYSCTL_DESCR("Information about mbuf owners"),
1.75 atatat 340: sysctl_kern_mbuf_mowners, 0, NULL, 0,
341: CTL_KERN, KERN_MBUF, MBUF_MOWNERS, CTL_EOL);
342: #endif /* MBUFTRACE */
1.28 thorpej 343: }
344:
1.103 thorpej 345: static void *
1.62 thorpej 346: mclpool_alloc(struct pool *pp, int flags)
1.28 thorpej 347: {
1.32 thorpej 348: boolean_t waitok = (flags & PR_WAITOK) ? TRUE : FALSE;
1.28 thorpej 349:
1.93 yamt 350: return ((void *)uvm_km_alloc_poolpage(mb_map, waitok));
1.1 cgd 351: }
352:
1.103 thorpej 353: static void
1.62 thorpej 354: mclpool_release(struct pool *pp, void *v)
1.1 cgd 355: {
356:
1.93 yamt 357: uvm_km_free_poolpage(mb_map, (vaddr_t)v);
1.65 thorpej 358: }
359:
360: /*ARGSUSED*/
361: static int
362: mb_ctor(void *arg, void *object, int flags)
363: {
364: struct mbuf *m = object;
365:
366: #ifdef POOL_VTOPHYS
367: m->m_paddr = POOL_VTOPHYS(m);
368: #else
369: m->m_paddr = M_PADDR_INVALID;
370: #endif
371: return (0);
1.1 cgd 372: }
373:
1.14 christos 374: void
1.59 thorpej 375: m_reclaim(void *arg, int flags)
1.1 cgd 376: {
1.27 matt 377: struct domain *dp;
1.81 matt 378: const struct protosw *pr;
1.27 matt 379: struct ifnet *ifp;
1.52 thorpej 380: int s = splvm();
1.1 cgd 381:
1.91 matt 382: DOMAIN_FOREACH(dp) {
1.33 thorpej 383: for (pr = dp->dom_protosw;
384: pr < dp->dom_protoswNPROTOSW; pr++)
385: if (pr->pr_drain)
386: (*pr->pr_drain)();
1.91 matt 387: }
1.92 matt 388: IFNET_FOREACH(ifp) {
1.27 matt 389: if (ifp->if_drain)
390: (*ifp->if_drain)(ifp);
1.92 matt 391: }
1.1 cgd 392: splx(s);
393: mbstat.m_drain++;
394: }
395:
396: /*
397: * Space allocation routines.
398: * These are also available as macros
399: * for critical paths.
400: */
401: struct mbuf *
1.62 thorpej 402: m_get(int nowait, int type)
1.1 cgd 403: {
1.27 matt 404: struct mbuf *m;
1.1 cgd 405:
1.5 cgd 406: MGET(m, nowait, type);
1.1 cgd 407: return (m);
408: }
409:
410: struct mbuf *
1.62 thorpej 411: m_gethdr(int nowait, int type)
1.1 cgd 412: {
1.27 matt 413: struct mbuf *m;
1.1 cgd 414:
1.5 cgd 415: MGETHDR(m, nowait, type);
1.1 cgd 416: return (m);
417: }
418:
419: struct mbuf *
1.62 thorpej 420: m_getclr(int nowait, int type)
1.1 cgd 421: {
1.27 matt 422: struct mbuf *m;
1.1 cgd 423:
1.5 cgd 424: MGET(m, nowait, type);
1.1 cgd 425: if (m == 0)
1.71 simonb 426: return (NULL);
1.30 perry 427: memset(mtod(m, caddr_t), 0, MLEN);
1.1 cgd 428: return (m);
429: }
430:
1.64 matt 431: void
432: m_clget(struct mbuf *m, int nowait)
433: {
1.71 simonb 434:
1.64 matt 435: MCLGET(m, nowait);
436: }
437:
1.1 cgd 438: struct mbuf *
1.62 thorpej 439: m_free(struct mbuf *m)
1.1 cgd 440: {
1.27 matt 441: struct mbuf *n;
1.1 cgd 442:
443: MFREE(m, n);
444: return (n);
445: }
446:
1.9 mycroft 447: void
1.62 thorpej 448: m_freem(struct mbuf *m)
1.1 cgd 449: {
1.27 matt 450: struct mbuf *n;
1.1 cgd 451:
452: if (m == NULL)
453: return;
454: do {
455: MFREE(m, n);
1.18 thorpej 456: m = n;
457: } while (m);
1.1 cgd 458: }
459:
1.64 matt 460: #ifdef MBUFTRACE
1.83 jonathan 461: /*
462: * Walk a chain of mbufs, claiming ownership of each mbuf in the chain.
463: */
1.64 matt 464: void
1.83 jonathan 465: m_claimm(struct mbuf *m, struct mowner *mo)
1.64 matt 466: {
1.71 simonb 467:
1.64 matt 468: for (; m != NULL; m = m->m_next)
469: MCLAIM(m, mo);
470: }
471: #endif
472:
1.1 cgd 473: /*
474: * Mbuffer utility routines.
475: */
476:
477: /*
478: * Lesser-used path for M_PREPEND:
479: * allocate new mbuf to prepend to chain,
480: * copy junk along.
481: */
482: struct mbuf *
1.62 thorpej 483: m_prepend(struct mbuf *m, int len, int how)
1.1 cgd 484: {
485: struct mbuf *mn;
486:
1.9 mycroft 487: MGET(mn, how, m->m_type);
1.1 cgd 488: if (mn == (struct mbuf *)NULL) {
489: m_freem(m);
490: return ((struct mbuf *)NULL);
491: }
492: if (m->m_flags & M_PKTHDR) {
1.101 yamt 493: M_MOVE_PKTHDR(mn, m);
1.64 matt 494: } else {
495: MCLAIM(mn, m->m_owner);
1.1 cgd 496: }
497: mn->m_next = m;
498: m = mn;
499: if (len < MHLEN)
500: MH_ALIGN(m, len);
501: m->m_len = len;
502: return (m);
503: }
504:
505: /*
506: * Make a copy of an mbuf chain starting "off0" bytes from the beginning,
507: * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf.
508: * The wait parameter is a choice of M_WAIT/M_DONTWAIT from caller.
509: */
510: int MCFail;
511:
512: struct mbuf *
1.62 thorpej 513: m_copym(struct mbuf *m, int off0, int len, int wait)
1.1 cgd 514: {
1.71 simonb 515:
1.44 itojun 516: return m_copym0(m, off0, len, wait, 0); /* shallow copy on M_EXT */
517: }
518:
519: struct mbuf *
1.62 thorpej 520: m_dup(struct mbuf *m, int off0, int len, int wait)
1.44 itojun 521: {
1.71 simonb 522:
1.44 itojun 523: return m_copym0(m, off0, len, wait, 1); /* deep copy */
524: }
525:
526: static struct mbuf *
1.62 thorpej 527: m_copym0(struct mbuf *m, int off0, int len, int wait, int deep)
1.44 itojun 528: {
1.27 matt 529: struct mbuf *n, **np;
530: int off = off0;
1.1 cgd 531: struct mbuf *top;
532: int copyhdr = 0;
533:
534: if (off < 0 || len < 0)
1.43 thorpej 535: panic("m_copym: off %d, len %d", off, len);
1.1 cgd 536: if (off == 0 && m->m_flags & M_PKTHDR)
537: copyhdr = 1;
538: while (off > 0) {
539: if (m == 0)
1.90 matt 540: panic("m_copym: m == 0, off %d", off);
1.1 cgd 541: if (off < m->m_len)
542: break;
543: off -= m->m_len;
544: m = m->m_next;
545: }
546: np = ⊤
547: top = 0;
548: while (len > 0) {
549: if (m == 0) {
550: if (len != M_COPYALL)
1.90 matt 551: panic("m_copym: m == 0, len %d [!COPYALL]",
552: len);
1.1 cgd 553: break;
554: }
555: MGET(n, wait, m->m_type);
556: *np = n;
557: if (n == 0)
558: goto nospace;
1.64 matt 559: MCLAIM(n, m->m_owner);
1.1 cgd 560: if (copyhdr) {
561: M_COPY_PKTHDR(n, m);
562: if (len == M_COPYALL)
563: n->m_pkthdr.len -= off0;
564: else
565: n->m_pkthdr.len = len;
566: copyhdr = 0;
567: }
1.9 mycroft 568: n->m_len = min(len, m->m_len - off);
1.1 cgd 569: if (m->m_flags & M_EXT) {
1.44 itojun 570: if (!deep) {
571: n->m_data = m->m_data + off;
572: n->m_ext = m->m_ext;
573: MCLADDREFERENCE(m, n);
574: } else {
1.48 itojun 575: /*
1.50 itojun 576: * we are unsure about the way m was allocated.
577: * copy into multiple MCLBYTES cluster mbufs.
1.48 itojun 578: */
1.44 itojun 579: MCLGET(n, wait);
1.50 itojun 580: n->m_len = 0;
581: n->m_len = M_TRAILINGSPACE(n);
582: n->m_len = min(n->m_len, len);
583: n->m_len = min(n->m_len, m->m_len - off);
584: memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + off,
1.44 itojun 585: (unsigned)n->m_len);
586: }
1.1 cgd 587: } else
1.30 perry 588: memcpy(mtod(n, caddr_t), mtod(m, caddr_t)+off,
1.1 cgd 589: (unsigned)n->m_len);
590: if (len != M_COPYALL)
591: len -= n->m_len;
1.50 itojun 592: off += n->m_len;
593: #ifdef DIAGNOSTIC
594: if (off > m->m_len)
595: panic("m_copym0 overrun");
596: #endif
597: if (off == m->m_len) {
598: m = m->m_next;
599: off = 0;
600: }
1.1 cgd 601: np = &n->m_next;
602: }
603: if (top == 0)
604: MCFail++;
605: return (top);
606: nospace:
607: m_freem(top);
608: MCFail++;
1.71 simonb 609: return (NULL);
1.1 cgd 610: }
611:
612: /*
1.18 thorpej 613: * Copy an entire packet, including header (which must be present).
614: * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'.
615: */
616: struct mbuf *
1.62 thorpej 617: m_copypacket(struct mbuf *m, int how)
1.18 thorpej 618: {
619: struct mbuf *top, *n, *o;
620:
621: MGET(n, how, m->m_type);
622: top = n;
623: if (!n)
624: goto nospace;
625:
1.64 matt 626: MCLAIM(n, m->m_owner);
1.18 thorpej 627: M_COPY_PKTHDR(n, m);
628: n->m_len = m->m_len;
629: if (m->m_flags & M_EXT) {
630: n->m_data = m->m_data;
631: n->m_ext = m->m_ext;
632: MCLADDREFERENCE(m, n);
633: } else {
1.30 perry 634: memcpy(mtod(n, char *), mtod(m, char *), n->m_len);
1.18 thorpej 635: }
636:
637: m = m->m_next;
638: while (m) {
639: MGET(o, how, m->m_type);
640: if (!o)
641: goto nospace;
642:
1.64 matt 643: MCLAIM(o, m->m_owner);
1.18 thorpej 644: n->m_next = o;
645: n = n->m_next;
646:
647: n->m_len = m->m_len;
648: if (m->m_flags & M_EXT) {
649: n->m_data = m->m_data;
650: n->m_ext = m->m_ext;
651: MCLADDREFERENCE(m, n);
652: } else {
1.30 perry 653: memcpy(mtod(n, char *), mtod(m, char *), n->m_len);
1.18 thorpej 654: }
655:
656: m = m->m_next;
657: }
658: return top;
659: nospace:
660: m_freem(top);
661: MCFail++;
1.71 simonb 662: return NULL;
1.18 thorpej 663: }
664:
665: /*
1.1 cgd 666: * Copy data from an mbuf chain starting "off" bytes from the beginning,
667: * continuing for "len" bytes, into the indicated buffer.
668: */
1.14 christos 669: void
1.100 martin 670: m_copydata(struct mbuf *m, int off, int len, void *vp)
1.1 cgd 671: {
1.94 tron 672: unsigned count;
1.95 tron 673: caddr_t cp = vp;
1.1 cgd 674:
675: if (off < 0 || len < 0)
1.90 matt 676: panic("m_copydata: off %d, len %d", off, len);
1.1 cgd 677: while (off > 0) {
1.94 tron 678: if (m == NULL)
679: panic("m_copydata: m == NULL, off %d", off);
1.1 cgd 680: if (off < m->m_len)
681: break;
682: off -= m->m_len;
683: m = m->m_next;
684: }
685: while (len > 0) {
1.94 tron 686: if (m == NULL)
687: panic("m_copydata: m == NULL, len %d", len);
1.9 mycroft 688: count = min(m->m_len - off, len);
1.30 perry 689: memcpy(cp, mtod(m, caddr_t) + off, count);
1.1 cgd 690: len -= count;
691: cp += count;
692: off = 0;
693: m = m->m_next;
694: }
695: }
696:
697: /*
698: * Concatenate mbuf chain n to m.
1.72 itojun 699: * n might be copied into m (when n->m_len is small), therefore data portion of
700: * n could be copied into an mbuf of different mbuf type.
1.1 cgd 701: * Any m_pkthdr is not updated.
702: */
1.14 christos 703: void
1.62 thorpej 704: m_cat(struct mbuf *m, struct mbuf *n)
1.1 cgd 705: {
1.73 yamt 706:
1.1 cgd 707: while (m->m_next)
708: m = m->m_next;
709: while (n) {
1.77 itojun 710: if (M_READONLY(m) || n->m_len > M_TRAILINGSPACE(m)) {
1.1 cgd 711: /* just join the two chains */
712: m->m_next = n;
713: return;
714: }
715: /* splat the data from one into the other */
1.30 perry 716: memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t),
1.1 cgd 717: (u_int)n->m_len);
718: m->m_len += n->m_len;
719: n = m_free(n);
720: }
721: }
722:
1.11 mycroft 723: void
1.62 thorpej 724: m_adj(struct mbuf *mp, int req_len)
1.1 cgd 725: {
1.27 matt 726: int len = req_len;
727: struct mbuf *m;
728: int count;
1.1 cgd 729:
730: if ((m = mp) == NULL)
731: return;
732: if (len >= 0) {
733: /*
734: * Trim from head.
735: */
736: while (m != NULL && len > 0) {
737: if (m->m_len <= len) {
738: len -= m->m_len;
739: m->m_len = 0;
740: m = m->m_next;
741: } else {
742: m->m_len -= len;
743: m->m_data += len;
744: len = 0;
745: }
746: }
747: m = mp;
748: if (mp->m_flags & M_PKTHDR)
749: m->m_pkthdr.len -= (req_len - len);
750: } else {
751: /*
752: * Trim from tail. Scan the mbuf chain,
753: * calculating its length and finding the last mbuf.
754: * If the adjustment only affects this mbuf, then just
755: * adjust and return. Otherwise, rescan and truncate
756: * after the remaining size.
757: */
758: len = -len;
759: count = 0;
760: for (;;) {
761: count += m->m_len;
762: if (m->m_next == (struct mbuf *)0)
763: break;
764: m = m->m_next;
765: }
766: if (m->m_len >= len) {
767: m->m_len -= len;
1.8 deraadt 768: if (mp->m_flags & M_PKTHDR)
769: mp->m_pkthdr.len -= len;
1.1 cgd 770: return;
771: }
772: count -= len;
773: if (count < 0)
774: count = 0;
775: /*
776: * Correct length for chain is "count".
777: * Find the mbuf with last data, adjust its length,
778: * and toss data from remaining mbufs on chain.
779: */
780: m = mp;
781: if (m->m_flags & M_PKTHDR)
782: m->m_pkthdr.len = count;
783: for (; m; m = m->m_next) {
784: if (m->m_len >= count) {
785: m->m_len = count;
786: break;
787: }
788: count -= m->m_len;
789: }
1.18 thorpej 790: while (m->m_next)
791: (m = m->m_next) ->m_len = 0;
1.1 cgd 792: }
793: }
794:
795: /*
1.102 skrll 796: * Rearrange an mbuf chain so that len bytes are contiguous
1.1 cgd 797: * and in the data area of an mbuf (so that mtod and dtom
798: * will work for a structure of size len). Returns the resulting
799: * mbuf chain on success, frees it and returns null on failure.
800: * If there is room, it will add up to max_protohdr-len extra bytes to the
801: * contiguous region in an attempt to avoid being called next time.
802: */
803: int MPFail;
804:
805: struct mbuf *
1.62 thorpej 806: m_pullup(struct mbuf *n, int len)
1.1 cgd 807: {
1.27 matt 808: struct mbuf *m;
809: int count;
1.1 cgd 810: int space;
811:
812: /*
813: * If first mbuf has no cluster, and has room for len bytes
814: * without shifting current data, pullup into it,
815: * otherwise allocate a new mbuf to prepend to the chain.
816: */
817: if ((n->m_flags & M_EXT) == 0 &&
818: n->m_data + len < &n->m_dat[MLEN] && n->m_next) {
819: if (n->m_len >= len)
820: return (n);
821: m = n;
822: n = n->m_next;
823: len -= m->m_len;
824: } else {
825: if (len > MHLEN)
826: goto bad;
827: MGET(m, M_DONTWAIT, n->m_type);
828: if (m == 0)
829: goto bad;
1.64 matt 830: MCLAIM(m, n->m_owner);
1.1 cgd 831: m->m_len = 0;
832: if (n->m_flags & M_PKTHDR) {
1.101 yamt 833: M_MOVE_PKTHDR(m, n);
1.1 cgd 834: }
835: }
836: space = &m->m_dat[MLEN] - (m->m_data + m->m_len);
837: do {
838: count = min(min(max(len, max_protohdr), space), n->m_len);
1.30 perry 839: memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t),
1.1 cgd 840: (unsigned)count);
841: len -= count;
842: m->m_len += count;
843: n->m_len -= count;
844: space -= count;
845: if (n->m_len)
846: n->m_data += count;
847: else
848: n = m_free(n);
849: } while (len > 0 && n);
850: if (len > 0) {
851: (void) m_free(m);
852: goto bad;
853: }
854: m->m_next = n;
855: return (m);
856: bad:
857: m_freem(n);
858: MPFail++;
1.71 simonb 859: return (NULL);
1.60 thorpej 860: }
861:
862: /*
863: * Like m_pullup(), except a new mbuf is always allocated, and we allow
864: * the amount of empty space before the data in the new mbuf to be specified
865: * (in the event that the caller expects to prepend later).
866: */
867: int MSFail;
868:
869: struct mbuf *
870: m_copyup(struct mbuf *n, int len, int dstoff)
871: {
872: struct mbuf *m;
873: int count, space;
874:
875: if (len > (MHLEN - dstoff))
876: goto bad;
877: MGET(m, M_DONTWAIT, n->m_type);
878: if (m == NULL)
879: goto bad;
1.64 matt 880: MCLAIM(m, n->m_owner);
1.60 thorpej 881: m->m_len = 0;
882: if (n->m_flags & M_PKTHDR) {
1.101 yamt 883: M_MOVE_PKTHDR(m, n);
1.60 thorpej 884: }
885: m->m_data += dstoff;
886: space = &m->m_dat[MLEN] - (m->m_data + m->m_len);
887: do {
888: count = min(min(max(len, max_protohdr), space), n->m_len);
889: memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t),
890: (unsigned)count);
891: len -= count;
892: m->m_len += count;
893: n->m_len -= count;
894: space -= count;
895: if (n->m_len)
896: n->m_data += count;
897: else
898: n = m_free(n);
899: } while (len > 0 && n);
900: if (len > 0) {
901: (void) m_free(m);
902: goto bad;
903: }
904: m->m_next = n;
905: return (m);
906: bad:
907: m_freem(n);
908: MSFail++;
909: return (NULL);
1.9 mycroft 910: }
911:
912: /*
913: * Partition an mbuf chain in two pieces, returning the tail --
914: * all but the first len0 bytes. In case of failure, it returns NULL and
915: * attempts to restore the chain to its original state.
916: */
917: struct mbuf *
1.62 thorpej 918: m_split(struct mbuf *m0, int len0, int wait)
1.9 mycroft 919: {
1.85 yamt 920:
1.87 yamt 921: return m_split0(m0, len0, wait, 1);
1.85 yamt 922: }
923:
924: static struct mbuf *
925: m_split0(struct mbuf *m0, int len0, int wait, int copyhdr)
926: {
1.27 matt 927: struct mbuf *m, *n;
1.22 thorpej 928: unsigned len = len0, remain, len_save;
1.9 mycroft 929:
930: for (m = m0; m && len > m->m_len; m = m->m_next)
931: len -= m->m_len;
932: if (m == 0)
1.71 simonb 933: return (NULL);
1.9 mycroft 934: remain = m->m_len - len;
1.85 yamt 935: if (copyhdr && (m0->m_flags & M_PKTHDR)) {
1.9 mycroft 936: MGETHDR(n, wait, m0->m_type);
937: if (n == 0)
1.71 simonb 938: return (NULL);
1.64 matt 939: MCLAIM(m, m0->m_owner);
1.9 mycroft 940: n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif;
941: n->m_pkthdr.len = m0->m_pkthdr.len - len0;
1.22 thorpej 942: len_save = m0->m_pkthdr.len;
1.9 mycroft 943: m0->m_pkthdr.len = len0;
944: if (m->m_flags & M_EXT)
945: goto extpacket;
946: if (remain > MHLEN) {
947: /* m can't be the lead packet */
948: MH_ALIGN(n, 0);
949: n->m_next = m_split(m, len, wait);
950: if (n->m_next == 0) {
951: (void) m_free(n);
1.22 thorpej 952: m0->m_pkthdr.len = len_save;
1.71 simonb 953: return (NULL);
1.9 mycroft 954: } else
955: return (n);
956: } else
957: MH_ALIGN(n, remain);
958: } else if (remain == 0) {
959: n = m->m_next;
960: m->m_next = 0;
961: return (n);
962: } else {
963: MGET(n, wait, m->m_type);
964: if (n == 0)
1.71 simonb 965: return (NULL);
1.64 matt 966: MCLAIM(n, m->m_owner);
1.9 mycroft 967: M_ALIGN(n, remain);
968: }
969: extpacket:
970: if (m->m_flags & M_EXT) {
971: n->m_ext = m->m_ext;
1.18 thorpej 972: MCLADDREFERENCE(m, n);
1.9 mycroft 973: n->m_data = m->m_data + len;
974: } else {
1.30 perry 975: memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + len, remain);
1.9 mycroft 976: }
977: n->m_len = remain;
978: m->m_len = len;
979: n->m_next = m->m_next;
980: m->m_next = 0;
981: return (n);
982: }
983: /*
984: * Routine to copy from device local memory into mbufs.
985: */
986: struct mbuf *
1.62 thorpej 987: m_devget(char *buf, int totlen, int off0, struct ifnet *ifp,
988: void (*copy)(const void *from, void *to, size_t len))
1.9 mycroft 989: {
1.27 matt 990: struct mbuf *m;
1.9 mycroft 991: struct mbuf *top = 0, **mp = ⊤
1.27 matt 992: int off = off0, len;
993: char *cp;
1.9 mycroft 994: char *epkt;
995:
996: cp = buf;
997: epkt = cp + totlen;
998: if (off) {
1.13 cgd 999: /*
1000: * If 'off' is non-zero, packet is trailer-encapsulated,
1001: * so we have to skip the type and length fields.
1002: */
1.104 perry 1003: cp += off + 2 * sizeof(uint16_t);
1004: totlen -= 2 * sizeof(uint16_t);
1.9 mycroft 1005: }
1006: MGETHDR(m, M_DONTWAIT, MT_DATA);
1007: if (m == 0)
1.71 simonb 1008: return (NULL);
1.9 mycroft 1009: m->m_pkthdr.rcvif = ifp;
1010: m->m_pkthdr.len = totlen;
1011: m->m_len = MHLEN;
1012:
1013: while (totlen > 0) {
1014: if (top) {
1015: MGET(m, M_DONTWAIT, MT_DATA);
1016: if (m == 0) {
1017: m_freem(top);
1.71 simonb 1018: return (NULL);
1.9 mycroft 1019: }
1020: m->m_len = MLEN;
1021: }
1022: len = min(totlen, epkt - cp);
1023: if (len >= MINCLSIZE) {
1024: MCLGET(m, M_DONTWAIT);
1.19 mycroft 1025: if ((m->m_flags & M_EXT) == 0) {
1.20 mycroft 1026: m_free(m);
1.19 mycroft 1027: m_freem(top);
1.71 simonb 1028: return (NULL);
1.19 mycroft 1029: }
1030: m->m_len = len = min(len, MCLBYTES);
1.9 mycroft 1031: } else {
1032: /*
1033: * Place initial small packet/header at end of mbuf.
1034: */
1035: if (len < m->m_len) {
1036: if (top == 0 && len + max_linkhdr <= m->m_len)
1037: m->m_data += max_linkhdr;
1038: m->m_len = len;
1039: } else
1040: len = m->m_len;
1041: }
1042: if (copy)
1.14 christos 1043: copy(cp, mtod(m, caddr_t), (size_t)len);
1.9 mycroft 1044: else
1.30 perry 1045: memcpy(mtod(m, caddr_t), cp, (size_t)len);
1.9 mycroft 1046: cp += len;
1047: *mp = m;
1048: mp = &m->m_next;
1049: totlen -= len;
1050: if (cp == epkt)
1051: cp = buf;
1052: }
1053: return (top);
1.18 thorpej 1054: }
1055:
1056: /*
1057: * Copy data from a buffer back into the indicated mbuf chain,
1058: * starting "off" bytes from the beginning, extending the mbuf
1059: * chain if necessary.
1060: */
1061: void
1.86 yamt 1062: m_copyback(struct mbuf *m0, int off, int len, const void *cp)
1.18 thorpej 1063: {
1.85 yamt 1064: #if defined(DEBUG)
1065: struct mbuf *origm = m0;
1066: int error;
1067: #endif /* defined(DEBUG) */
1068:
1069: if (m0 == NULL)
1070: return;
1071:
1072: #if defined(DEBUG)
1073: error =
1074: #endif /* defined(DEBUG) */
1075: m_copyback0(&m0, off, len, cp,
1076: M_COPYBACK0_COPYBACK|M_COPYBACK0_EXTEND, M_DONTWAIT);
1077:
1078: #if defined(DEBUG)
1079: if (error != 0 || (m0 != NULL && origm != m0))
1080: panic("m_copyback");
1081: #endif /* defined(DEBUG) */
1082: }
1083:
1084: struct mbuf *
1.86 yamt 1085: m_copyback_cow(struct mbuf *m0, int off, int len, const void *cp, int how)
1.85 yamt 1086: {
1087: int error;
1088:
1089: /* don't support chain expansion */
1090: KDASSERT(off + len <= m_length(m0));
1091:
1092: error = m_copyback0(&m0, off, len, cp,
1093: M_COPYBACK0_COPYBACK|M_COPYBACK0_COW, how);
1094: if (error) {
1095: /*
1096: * no way to recover from partial success.
1097: * just free the chain.
1098: */
1099: m_freem(m0);
1100: return NULL;
1101: }
1102: return m0;
1103: }
1104:
1105: /*
1106: * m_makewritable: ensure the specified range writable.
1107: */
1108: int
1109: m_makewritable(struct mbuf **mp, int off, int len, int how)
1110: {
1111: int error;
1112: #if defined(DEBUG)
1113: struct mbuf *n;
1114: int origlen, reslen;
1115:
1116: origlen = m_length(*mp);
1117: #endif /* defined(DEBUG) */
1118:
1119: #if 0 /* M_COPYALL is large enough */
1120: if (len == M_COPYALL)
1121: len = m_length(*mp) - off; /* XXX */
1122: #endif
1123:
1124: error = m_copyback0(mp, off, len, NULL,
1125: M_COPYBACK0_PRESERVE|M_COPYBACK0_COW, how);
1126:
1127: #if defined(DEBUG)
1128: reslen = 0;
1129: for (n = *mp; n; n = n->m_next)
1130: reslen += n->m_len;
1131: if (origlen != reslen)
1132: panic("m_makewritable: length changed");
1133: if (((*mp)->m_flags & M_PKTHDR) != 0 && reslen != (*mp)->m_pkthdr.len)
1134: panic("m_makewritable: inconsist");
1135: #endif /* defined(DEBUG) */
1136:
1137: return error;
1138: }
1139:
1140: int
1.86 yamt 1141: m_copyback0(struct mbuf **mp0, int off, int len, const void *vp, int flags,
1142: int how)
1.85 yamt 1143: {
1.27 matt 1144: int mlen;
1.85 yamt 1145: struct mbuf *m, *n;
1146: struct mbuf **mp;
1.18 thorpej 1147: int totlen = 0;
1.86 yamt 1148: const char *cp = vp;
1.18 thorpej 1149:
1.85 yamt 1150: KASSERT(mp0 != NULL);
1151: KASSERT(*mp0 != NULL);
1152: KASSERT((flags & M_COPYBACK0_PRESERVE) == 0 || cp == NULL);
1153: KASSERT((flags & M_COPYBACK0_COPYBACK) == 0 || cp != NULL);
1154:
1155: mp = mp0;
1156: m = *mp;
1.18 thorpej 1157: while (off > (mlen = m->m_len)) {
1158: off -= mlen;
1159: totlen += mlen;
1160: if (m->m_next == 0) {
1.85 yamt 1161: if ((flags & M_COPYBACK0_EXTEND) == 0)
1162: goto out;
1163: n = m_getclr(how, m->m_type);
1.18 thorpej 1164: if (n == 0)
1165: goto out;
1166: n->m_len = min(MLEN, len + off);
1167: m->m_next = n;
1168: }
1.85 yamt 1169: mp = &m->m_next;
1.18 thorpej 1170: m = m->m_next;
1171: }
1172: while (len > 0) {
1.85 yamt 1173: mlen = m->m_len - off;
1174: if (mlen != 0 && M_READONLY(m)) {
1175: char *datap;
1176: int eatlen;
1177:
1178: /*
1179: * this mbuf is read-only.
1180: * allocate a new writable mbuf and try again.
1181: */
1182:
1183: #if defined(DIAGNOSTIC)
1184: if ((flags & M_COPYBACK0_COW) == 0)
1185: panic("m_copyback0: read-only");
1186: #endif /* defined(DIAGNOSTIC) */
1187:
1188: /*
1189: * if we're going to write into the middle of
1190: * a mbuf, split it first.
1191: */
1192: if (off > 0 && len < mlen) {
1193: n = m_split0(m, off, how, 0);
1194: if (n == NULL)
1195: goto enobufs;
1196: m->m_next = n;
1197: mp = &m->m_next;
1198: m = n;
1199: off = 0;
1200: continue;
1201: }
1202:
1203: /*
1204: * XXX TODO coalesce into the trailingspace of
1205: * the previous mbuf when possible.
1206: */
1207:
1208: /*
1209: * allocate a new mbuf. copy packet header if needed.
1210: */
1211: MGET(n, how, m->m_type);
1212: if (n == NULL)
1213: goto enobufs;
1214: MCLAIM(n, m->m_owner);
1215: if (off == 0 && (m->m_flags & M_PKTHDR) != 0) {
1.101 yamt 1216: M_MOVE_PKTHDR(n, m);
1.85 yamt 1217: n->m_len = MHLEN;
1218: } else {
1219: if (len >= MINCLSIZE)
1220: MCLGET(n, M_DONTWAIT);
1221: n->m_len =
1222: (n->m_flags & M_EXT) ? MCLBYTES : MLEN;
1223: }
1224: if (n->m_len > len)
1225: n->m_len = len;
1226:
1227: /*
1228: * free the region which has been overwritten.
1229: * copying data from old mbufs if requested.
1230: */
1231: if (flags & M_COPYBACK0_PRESERVE)
1232: datap = mtod(n, char *);
1233: else
1234: datap = NULL;
1235: eatlen = n->m_len;
1236: KDASSERT(off == 0 || eatlen >= mlen);
1237: if (off > 0) {
1238: KDASSERT(len >= mlen);
1239: m->m_len = off;
1240: m->m_next = n;
1241: if (datap) {
1242: m_copydata(m, off, mlen, datap);
1243: datap += mlen;
1244: }
1245: eatlen -= mlen;
1246: mp = &m->m_next;
1247: m = m->m_next;
1248: }
1249: while (m != NULL && M_READONLY(m) &&
1250: n->m_type == m->m_type && eatlen > 0) {
1251: mlen = min(eatlen, m->m_len);
1252: if (datap) {
1253: m_copydata(m, 0, mlen, datap);
1254: datap += mlen;
1255: }
1256: m->m_data += mlen;
1257: m->m_len -= mlen;
1258: eatlen -= mlen;
1259: if (m->m_len == 0)
1260: *mp = m = m_free(m);
1261: }
1262: if (eatlen > 0)
1263: n->m_len -= eatlen;
1264: n->m_next = m;
1265: *mp = m = n;
1266: continue;
1267: }
1268: mlen = min(mlen, len);
1269: if (flags & M_COPYBACK0_COPYBACK) {
1270: memcpy(mtod(m, caddr_t) + off, cp, (unsigned)mlen);
1271: cp += mlen;
1272: }
1.18 thorpej 1273: len -= mlen;
1274: mlen += off;
1275: off = 0;
1276: totlen += mlen;
1277: if (len == 0)
1278: break;
1279: if (m->m_next == 0) {
1.85 yamt 1280: if ((flags & M_COPYBACK0_EXTEND) == 0)
1281: goto out;
1282: n = m_get(how, m->m_type);
1.18 thorpej 1283: if (n == 0)
1284: break;
1285: n->m_len = min(MLEN, len);
1286: m->m_next = n;
1287: }
1.85 yamt 1288: mp = &m->m_next;
1.18 thorpej 1289: m = m->m_next;
1290: }
1.85 yamt 1291: out: if (((m = *mp0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen))
1.18 thorpej 1292: m->m_pkthdr.len = totlen;
1.85 yamt 1293:
1294: return 0;
1295:
1296: enobufs:
1297: return ENOBUFS;
1.66 thorpej 1298: }
1299:
1.101 yamt 1300: void
1301: m_move_pkthdr(struct mbuf *to, struct mbuf *from)
1302: {
1303:
1304: KASSERT((to->m_flags & M_EXT) == 0);
1305: KASSERT((to->m_flags & M_PKTHDR) == 0 || m_tag_first(to) == NULL);
1306: KASSERT((from->m_flags & M_PKTHDR) != 0);
1307:
1308: to->m_pkthdr = from->m_pkthdr;
1309: to->m_flags = from->m_flags & M_COPYFLAGS;
1310: to->m_data = to->m_pktdat;
1311:
1312: from->m_flags &= ~M_PKTHDR;
1313: }
1314:
1.66 thorpej 1315: /*
1316: * Apply function f to the data in an mbuf chain starting "off" bytes from the
1317: * beginning, continuing for "len" bytes.
1318: */
1319: int
1320: m_apply(struct mbuf *m, int off, int len,
1321: int (*f)(void *, caddr_t, unsigned int), void *arg)
1322: {
1323: unsigned int count;
1324: int rval;
1325:
1326: KASSERT(len >= 0);
1327: KASSERT(off >= 0);
1328:
1329: while (off > 0) {
1330: KASSERT(m != NULL);
1331: if (off < m->m_len)
1332: break;
1333: off -= m->m_len;
1334: m = m->m_next;
1335: }
1336: while (len > 0) {
1337: KASSERT(m != NULL);
1338: count = min(m->m_len - off, len);
1339:
1340: rval = (*f)(arg, mtod(m, caddr_t) + off, count);
1341: if (rval)
1342: return (rval);
1343:
1344: len -= count;
1345: off = 0;
1346: m = m->m_next;
1347: }
1348:
1349: return (0);
1350: }
1351:
1352: /*
1353: * Return a pointer to mbuf/offset of location in mbuf chain.
1354: */
1355: struct mbuf *
1356: m_getptr(struct mbuf *m, int loc, int *off)
1357: {
1358:
1359: while (loc >= 0) {
1360: /* Normal end of search */
1361: if (m->m_len > loc) {
1362: *off = loc;
1363: return (m);
1364: } else {
1365: loc -= m->m_len;
1366:
1367: if (m->m_next == NULL) {
1368: if (loc == 0) {
1369: /* Point at the end of valid data */
1370: *off = m->m_len;
1371: return (m);
1372: } else
1373: return (NULL);
1374: } else
1375: m = m->m_next;
1376: }
1377: }
1378:
1379: return (NULL);
1.1 cgd 1380: }
1.105 ! yamt 1381:
! 1382: #if defined(DDB)
! 1383: void
! 1384: m_print(const struct mbuf *m, const char *modif, void (*pr)(const char *, ...))
! 1385: {
! 1386: char ch;
! 1387: boolean_t opt_c = FALSE;
! 1388: char buf[512];
! 1389:
! 1390: while ((ch = *(modif++)) != '\0') {
! 1391: switch (ch) {
! 1392: case 'c':
! 1393: opt_c = TRUE;
! 1394: break;
! 1395: }
! 1396: }
! 1397:
! 1398: nextchain:
! 1399: (*pr)("MBUF %p\n", m);
! 1400: bitmask_snprintf(m->m_flags, M_FLAGS_BITS, buf, sizeof(buf));
! 1401: (*pr)(" data=%p, len=%d, type=%d, flags=0x%s\n",
! 1402: m->m_data, m->m_len, m->m_type, buf);
! 1403: (*pr)(" owner=%p, next=%p, nextpkt=%p\n", m->m_owner, m->m_next,
! 1404: m->m_nextpkt);
! 1405: (*pr)(" leadingspace=%u, trailingspace=%u, readonly=%u\n",
! 1406: (int)M_LEADINGSPACE(m), (int)M_TRAILINGSPACE(m),
! 1407: (int)M_READONLY(m));
! 1408: if ((m->m_flags & M_PKTHDR) != 0) {
! 1409: bitmask_snprintf(m->m_pkthdr.csum_flags, M_CSUM_BITS, buf,
! 1410: sizeof(buf));
! 1411: (*pr)(" pktlen=%d, rcvif=%p, csum_flags=0x%s, csum_data=0x%"
! 1412: PRIx32 ", segsz=%u\n",
! 1413: m->m_pkthdr.len, m->m_pkthdr.rcvif,
! 1414: buf, m->m_pkthdr.csum_data, m->m_pkthdr.segsz);
! 1415: }
! 1416: if ((m->m_flags & M_EXT)) {
! 1417: (*pr)(" shared=%u, ext_buf=%p, ext_size=%zd, "
! 1418: "ext_free=%p, ext_arg=%p\n",
! 1419: (int)MCLISREFERENCED(m),
! 1420: m->m_ext.ext_buf, m->m_ext.ext_size,
! 1421: m->m_ext.ext_free, m->m_ext.ext_arg);
! 1422: }
! 1423: if ((~m->m_flags & (M_EXT|M_EXT_PAGES)) == 0) {
! 1424: int i;
! 1425:
! 1426: (*pr)(" pages:");
! 1427: for (i = 0; i < m->m_ext.ext_size; i += PAGE_SIZE) {
! 1428: (*pr)(" %p", m->m_ext.ext_pgs[i]);
! 1429: }
! 1430: (*pr)("\n");
! 1431: }
! 1432:
! 1433: if (opt_c) {
! 1434: m = m->m_next;
! 1435: if (m != NULL) {
! 1436: goto nextchain;
! 1437: }
! 1438: }
! 1439: }
! 1440: #endif /* defined(DDB) */
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