add more protocol specific m_flag bits
[dragonfly.git] / sys / sys / mbuf.h
CommitLineData
984263bc 1/*
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2 * Copyright (c) 2004 The DragonFly Project. All rights reserved.
3 *
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4 * Copyright (c) 1982, 1986, 1988, 1993
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by the University of
18 * California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 * may be used to endorse or promote products derived from this software
21 * without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95
36 * $FreeBSD: src/sys/sys/mbuf.h,v 1.44.2.17 2003/04/15 06:15:02 silby Exp $
cf12ba3c 37 * $DragonFly: src/sys/sys/mbuf.h,v 1.54 2008/10/19 08:39:55 sephe Exp $
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38 */
39
40#ifndef _SYS_MBUF_H_
41#define _SYS_MBUF_H_
42
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43#if defined(_KERNEL) || defined(_KERNEL_STRUCTURES)
44
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45#ifndef _SYS_TYPES_H_
46#include <sys/types.h>
47#endif
48#ifndef _SYS_PARAM_H_
49#include <sys/param.h>
50#endif
51#ifndef _SYS_QUEUE_H_
984263bc 52#include <sys/queue.h>
1bd40720 53#endif
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54#ifndef _NET_NETISR_H_
55#include <net/netisr.h>
56#endif
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57
58/*
59 * Mbufs are of a single size, MSIZE (machine/param.h), which
60 * includes overhead. An mbuf may add a single "mbuf cluster" of size
61 * MCLBYTES (also in machine/param.h), which has no additional overhead
62 * and is used instead of the internal data area; this is done when
63 * at least MINCLSIZE of data must be stored.
64 */
65#define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */
66#define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */
67#define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */
68#define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */
69
70/*
71 * Macros for type conversion:
72 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type.
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73 * mtocl(x) - convert pointer within cluster to cluster index #
74 * cltom(x) - convert cluster # to ptr to beginning of cluster
75 */
76#define mtod(m, t) ((t)((m)->m_data))
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77
78/*
79 * Header present at the beginning of every mbuf.
80 */
81struct m_hdr {
82 struct mbuf *mh_next; /* next buffer in chain */
83 struct mbuf *mh_nextpkt; /* next chain in queue/record */
84 caddr_t mh_data; /* location of data */
85 int mh_len; /* amount of data in this mbuf */
1514ff2e 86 int mh_flags; /* flags; see below */
984263bc 87 short mh_type; /* type of data in this mbuf */
1514ff2e 88 short mh_pad; /* padding */
6aad077d 89 struct netmsg_packet mh_netmsg; /* hardware->proto stack msg */
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90};
91
92/*
93 * Packet tag structure (see below for details).
94 */
95struct m_tag {
96 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */
97 u_int16_t m_tag_id; /* Tag ID */
98 u_int16_t m_tag_len; /* Length of data */
99 u_int32_t m_tag_cookie; /* ABI/Module ID */
100};
101
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102SLIST_HEAD(packet_tags, m_tag);
103
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104/*
105 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
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106 *
107 * Be careful: The fields have been carefully ordered to avoid hidden padding.
108 * Keep this in mind, when adding or removing fields!
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109 */
110struct pkthdr {
111 struct ifnet *rcvif; /* rcv interface */
112 int len; /* total packet length */
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113 struct packet_tags tags; /* list of packet tags */
114
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115 /* variables for ip and tcp reassembly */
116 void *header; /* pointer to packet header */
46ca7d86 117
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118 /* variables for hardware checksum */
119 int csum_flags; /* flags regarding checksum */
120 int csum_data; /* data field used by csum routines */
46ca7d86 121
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122 /* firewall flags */
123 uint32_t fw_flags; /* flags for PF */
124
02742ec6 125 /* variables for PF processing */
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126 uint16_t pf_tag; /* PF tag id */
127 uint8_t pf_routed; /* PF routing counter */
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128
129 /* variables for ALTQ processing */
130 uint8_t ecn_af; /* address family for ECN */
131 uint32_t altq_qid; /* queue id */
5950bf01 132 uint32_t altq_state_hash; /* identifies 'connections' */
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133
134 uint16_t ether_vlantag; /* ethernet 802.1p+q vlan tag */
6afb09f8 135 uint16_t hash; /* packet hash */
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136};
137
138/*
139 * Description of external storage mapped into mbuf; valid only if M_EXT is set.
140 */
141struct m_ext {
142 caddr_t ext_buf; /* start of buffer */
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143 void (*ext_free)(void *);
144 u_int ext_size; /* size of buffer, for ext_free */
145 void (*ext_ref)(void *);
7eccf245 146 void *ext_arg;
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147};
148
149/*
150 * The core of the mbuf object along with some shortcut defines for
151 * practical purposes.
152 */
153struct mbuf {
154 struct m_hdr m_hdr;
155 union {
156 struct {
157 struct pkthdr MH_pkthdr; /* M_PKTHDR set */
158 union {
159 struct m_ext MH_ext; /* M_EXT set */
160 char MH_databuf[MHLEN];
161 } MH_dat;
162 } MH;
163 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */
164 } M_dat;
165};
166#define m_next m_hdr.mh_next
167#define m_len m_hdr.mh_len
168#define m_data m_hdr.mh_data
169#define m_type m_hdr.mh_type
170#define m_flags m_hdr.mh_flags
171#define m_nextpkt m_hdr.mh_nextpkt
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172#define m_pkthdr M_dat.MH.MH_pkthdr
173#define m_ext M_dat.MH.MH_dat.MH_ext
174#define m_pktdat M_dat.MH.MH_dat.MH_databuf
175#define m_dat M_dat.M_databuf
176
177/*
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178 * Code that uses m_act should be converted to use m_nextpkt
179 * instead; m_act is historical and deprecated.
180 */
181#define m_act m_nextpkt
182
183/*
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184 * mbuf flags.
185 */
186#define M_EXT 0x0001 /* has associated external storage */
187#define M_PKTHDR 0x0002 /* start of record */
188#define M_EOR 0x0004 /* end of record */
189#define M_PROTO1 0x0008 /* protocol-specific */
190#define M_PROTO2 0x0010 /* protocol-specific */
191#define M_PROTO3 0x0020 /* protocol-specific */
192#define M_PROTO4 0x0040 /* protocol-specific */
193#define M_PROTO5 0x0080 /* protocol-specific */
194
195/*
196 * mbuf pkthdr flags (also stored in m_flags).
197 */
198#define M_BCAST 0x0100 /* send/received as link-level broadcast */
199#define M_MCAST 0x0200 /* send/received as link-level multicast */
200#define M_FRAG 0x0400 /* packet is a fragment of a larger packet */
201#define M_FIRSTFRAG 0x0800 /* packet is first fragment */
202#define M_LASTFRAG 0x1000 /* packet is last fragment */
77e294a1 203#define M_CLCACHE 0x2000 /* mbuf allocated from the cluster cache */
90775e29 204#define M_EXT_CLUSTER 0x4000 /* standard cluster else special */
77e294a1 205#define M_PHCACHE 0x8000 /* mbuf allocated from the pkt header cache */
78812139 206#define M_NOTIFICATION 0x10000 /* notification event */
83790f85 207#define M_VLANTAG 0x20000 /* ether_vlantag is valid */
cb8d752c 208#define M_MPLSLABELED 0x40000 /* packet is mpls labeled */
8697599b 209#define M_LENCHECKED 0x80000 /* packet proto lengths are checked */
6afb09f8 210#define M_HASH 0x100000/* hash field in pkthdr is valid */
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211#define M_PROTO6 0x200000/* protocol-specific */
212#define M_PROTO7 0x400000/* protocol-specific */
213#define M_PROTO8 0x800000/* protocol-specific */
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214
215/*
216 * Flags copied when copying m_pkthdr.
217 */
ee42237d 218#define M_COPYFLAGS (M_PKTHDR|M_EOR|M_PROTO1|M_PROTO2|M_PROTO3 | \
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219 M_PROTO4|M_PROTO5|M_PROTO6|M_PROTO7|M_PROTO8 | \
220 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG | \
221 M_VLANTAG|M_MPLSLABELED | \
6afb09f8 222 M_LENCHECKED|M_HASH)
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223
224/*
225 * Flags indicating hw checksum support and sw checksum requirements.
226 */
227#define CSUM_IP 0x0001 /* will csum IP */
228#define CSUM_TCP 0x0002 /* will csum TCP */
229#define CSUM_UDP 0x0004 /* will csum UDP */
230#define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */
231#define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */
232
233#define CSUM_IP_CHECKED 0x0100 /* did csum IP */
234#define CSUM_IP_VALID 0x0200 /* ... the csum is valid */
235#define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */
236#define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */
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237#define CSUM_FRAG_NOT_CHECKED 0x1000 /* did _not_ csum fragment
238 * NB: This flag is only used
239 * by IP defragmenter.
240 */
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241
242#define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP)
243#define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */
244
245/*
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246 * Flags indicating PF processing status
247 */
f2c2ec09 248#define FW_MBUF_GENERATED 0x00000001
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249#define PF_MBUF_TAGGED 0x00000002 /* pf_tag field is valid */
250#define PF_MBUF_ROUTED 0x00000004 /* pf_routed field is valid */
251#define PF_MBUF_TRANSLATE_LOCALHOST \
252 0x00000008
253#define PF_MBUF_FRAGCACHE 0x00000010
4d723e5a 254#define ALTQ_MBUF_TAGGED 0x00000020 /* altq_qid is valid */
5de23090 255#define IPFORWARD_MBUF_TAGGED 0x00000040
84a3e25a 256#define DUMMYNET_MBUF_TAGGED 0x00000080
5950bf01 257#define ALTQ_MBUF_STATE_HASHED 0x00000100
012d335d 258#define FW_MBUF_REDISPATCH 0x00000200
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259#define PF_MBUF_GENERATED FW_MBUF_GENERATED
260#define IPFW_MBUF_GENERATED FW_MBUF_GENERATED
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261
262/*
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263 * mbuf types.
264 */
265#define MT_FREE 0 /* should be on free list */
266#define MT_DATA 1 /* dynamic (data) allocation */
267#define MT_HEADER 2 /* packet header */
60ed1291 268#define MT_SONAME 3 /* socket name */
5de23090 269/* 4 was MT_TAG */
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270#define MT_CONTROL 5 /* extra-data protocol message */
271#define MT_OOBDATA 6 /* expedited data */
272#define MT_NTYPES 7 /* number of mbuf types for mbtypes[] */
984263bc 273
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274struct mbuf_chain {
275 struct mbuf *mc_head;
276 struct mbuf *mc_tail;
277};
278
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279/*
280 * General mbuf allocator statistics structure.
281 */
282struct mbstat {
283 u_long m_mbufs; /* mbufs obtained from page pool */
284 u_long m_clusters; /* clusters obtained from page pool */
285 u_long m_spare; /* spare field */
286 u_long m_clfree; /* free clusters */
287 u_long m_drops; /* times failed to find space */
288 u_long m_wait; /* times waited for space */
289 u_long m_drain; /* times drained protocols for space */
290 u_long m_mcfail; /* times m_copym failed */
291 u_long m_mpfail; /* times m_pullup failed */
292 u_long m_msize; /* length of an mbuf */
293 u_long m_mclbytes; /* length of an mbuf cluster */
294 u_long m_minclsize; /* min length of data to allocate a cluster */
295 u_long m_mlen; /* length of data in an mbuf */
296 u_long m_mhlen; /* length of data in a header mbuf */
297};
298
299/*
300 * Flags specifying how an allocation should be made.
301 */
302
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303#define MB_DONTWAIT 0x4
304#define MB_TRYWAIT 0x8
305#define MB_WAIT MB_TRYWAIT
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306
307/*
308 * Mbuf to Malloc Flag Conversion.
309 */
74f1caca 310#define MBTOM(how) ((how) & MB_TRYWAIT ? M_WAITOK : M_NOWAIT)
984263bc 311
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312/*
313 * These are identifying numbers passed to the m_mballoc_wait function,
314 * allowing us to determine whether the call came from an MGETHDR or
315 * an MGET.
316 */
317#define MGETHDR_C 1
318#define MGET_C 2
319
320/*
12496bdf 321 * mbuf allocation/deallocation macros (YYY deprecated, too big):
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322 *
323 * MGET(struct mbuf *m, int how, int type)
324 * allocates an mbuf and initializes it to contain internal data.
325 *
326 * MGETHDR(struct mbuf *m, int how, int type)
327 * allocates an mbuf and initializes it to contain a packet header
328 * and internal data.
329 */
330#define MGET(m, how, type) do { \
12496bdf 331 (m) = m_get((how), (type)); \
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332} while (0)
333
334#define MGETHDR(m, how, type) do { \
12496bdf 335 (m) = m_gethdr((how), (type)); \
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336} while (0)
337
338/*
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339 * MCLGET adds such clusters to a normal mbuf. The flag M_EXT is set upon
340 * success.
50503f0f 341 * Deprecated. Use m_getcl() or m_getl() instead.
984263bc 342 */
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343#define MCLGET(m, how) do { \
344 m_mclget((m), (how)); \
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345} while (0)
346
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347/*
348 * NB: M_COPY_PKTHDR is deprecated; use either M_MOVE_PKTHDR
349 * or m_dup_pkthdr.
350 */
351/*
352 * Move mbuf pkthdr from "from" to "to".
353 * from should have M_PKTHDR set, and to must be empty.
354 * from no longer has a pkthdr after this operation.
355 */
356#define M_MOVE_PKTHDR(_to, _from) m_move_pkthdr((_to), (_from))
357
358/*
359 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place
360 * an object of the specified size at the end of the mbuf, longword aligned.
361 */
362#define M_ALIGN(m, len) do { \
363 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \
364} while (0)
365
366/*
367 * As above, for mbufs allocated with m_gethdr/MGETHDR
368 * or initialized by M_COPY_PKTHDR.
369 */
370#define MH_ALIGN(m, len) do { \
371 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \
372} while (0)
373
374/*
375 * Check if we can write to an mbuf.
376 */
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377#define M_EXT_WRITABLE(m) (m_sharecount(m) == 1)
378#define M_WRITABLE(m) (!((m)->m_flags & M_EXT) || M_EXT_WRITABLE(m))
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379
380/*
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381 * Check if the supplied mbuf has a packet header, or else panic.
382 */
383#define M_ASSERTPKTHDR(m) \
384 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \
385 ("%s: invalid mbuf or no mbuf packet header!", __func__))
386
387/*
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388 * Compute the amount of space available before the current start of data.
389 * The M_EXT_WRITABLE() is a temporary, conservative safety measure: the burden
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390 * of checking writability of the mbuf data area rests solely with the caller.
391 */
392#define M_LEADINGSPACE(m) \
393 ((m)->m_flags & M_EXT ? \
394 (M_EXT_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \
395 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
396 (m)->m_data - (m)->m_dat)
397
398/*
7b6f875f 399 * Compute the amount of space available after the end of data in an mbuf.
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400 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
401 * of checking writability of the mbuf data area rests solely with the caller.
402 */
403#define M_TRAILINGSPACE(m) \
404 ((m)->m_flags & M_EXT ? \
405 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \
406 - ((m)->m_data + (m)->m_len) : 0) : \
407 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
408
409/*
410 * Arrange to prepend space of size plen to mbuf m.
411 * If a new mbuf must be allocated, how specifies whether to wait.
74f1caca 412 * If how is MB_DONTWAIT and allocation fails, the original mbuf chain
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413 * is freed and m is set to NULL.
414 */
415#define M_PREPEND(m, plen, how) do { \
416 struct mbuf **_mmp = &(m); \
417 struct mbuf *_mm = *_mmp; \
418 int _mplen = (plen); \
419 int __mhow = (how); \
420 \
421 if (M_LEADINGSPACE(_mm) >= _mplen) { \
422 _mm->m_data -= _mplen; \
423 _mm->m_len += _mplen; \
424 } else \
425 _mm = m_prepend(_mm, _mplen, __mhow); \
426 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \
427 _mm->m_pkthdr.len += _mplen; \
428 *_mmp = _mm; \
429} while (0)
430
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431/* Length to m_copy to copy all. */
432#define M_COPYALL 1000000000
433
434/* Compatibility with 4.3 */
74f1caca 435#define m_copy(m, o, l) m_copym((m), (o), (l), MB_DONTWAIT)
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436
437#ifdef _KERNEL
438extern u_int m_clalloc_wid; /* mbuf cluster wait count */
439extern u_int m_mballoc_wid; /* mbuf wait count */
440extern int max_linkhdr; /* largest link-level header */
441extern int max_protohdr; /* largest protocol header */
442extern int max_hdr; /* largest link+protocol header */
443extern int max_datalen; /* MHLEN - max_hdr */
984263bc 444extern int mbuf_wait; /* mbuf sleep time */
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445extern int nmbclusters;
446extern int nmbufs;
984263bc 447
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448struct uio;
449
984263bc 450void m_adj(struct mbuf *, int);
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451int m_apply(struct mbuf *, int, int,
452 int (*)(void *, void *, u_int), void *);
984263bc 453void m_cat(struct mbuf *, struct mbuf *);
df80f2ea 454u_int m_countm(struct mbuf *m, struct mbuf **lastm, u_int *mbcnt);
984263bc 455void m_copyback(struct mbuf *, int, int, caddr_t);
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456void m_copydata(const struct mbuf *, int, int, caddr_t);
457struct mbuf *m_copym(const struct mbuf *, int, int, int);
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458struct mbuf *m_copypacket(struct mbuf *, int);
459struct mbuf *m_defrag(struct mbuf *, int);
c8f5127a 460struct mbuf *m_defrag_nofree(struct mbuf *, int);
984263bc 461struct mbuf *m_devget(char *, int, int, struct ifnet *,
50503f0f 462 void (*copy)(volatile const void *, volatile void *, size_t));
984263bc 463struct mbuf *m_dup(struct mbuf *, int);
f15db79e 464int m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
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465struct mbuf *m_free(struct mbuf *);
466void m_freem(struct mbuf *);
467struct mbuf *m_get(int, int);
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468struct mbuf *m_getc(int len, int how, int type);
469struct mbuf *m_getcl(int how, short type, int flags);
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470struct mbuf *m_getclr(int, int);
471struct mbuf *m_gethdr(int, int);
472struct mbuf *m_getm(struct mbuf *, int, int, int);
920c9f10 473struct mbuf *m_getptr(struct mbuf *, int, int *);
50503f0f 474struct mbuf *m_last(struct mbuf *m);
df80f2ea 475u_int m_lengthm(struct mbuf *m, struct mbuf **lastm);
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476void m_move_pkthdr(struct mbuf *, struct mbuf *);
477struct mbuf *m_prepend(struct mbuf *, int, int);
478void m_print(const struct mbuf *m);
479struct mbuf *m_pulldown(struct mbuf *, int, int, int *);
480struct mbuf *m_pullup(struct mbuf *, int);
984263bc 481struct mbuf *m_split(struct mbuf *, int, int);
e12241e1 482struct mbuf *m_uiomove(struct uio *);
b6650ec0 483void m_mclget(struct mbuf *m, int how);
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484int m_sharecount(struct mbuf *m);
485void m_chtype(struct mbuf *m, int type);
cf12ba3c 486int m_devpad(struct mbuf *m, int padto);
90775e29 487
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488#ifdef MBUF_DEBUG
489void mbuftrackid(struct mbuf *, int);
490#else
491#define mbuftrackid(m, id) /* empty */
492#endif
493
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494/*
495 * Allocate the right type of mbuf for the desired total length.
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496 * The mbuf returned does not necessarily cover the entire requested length.
497 * This function follows mbuf chaining policy of allowing MINCLSIZE
498 * amount of chained mbufs.
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499 */
500static __inline struct mbuf *
501m_getl(int len, int how, int type, int flags, int *psize)
502{
503 struct mbuf *m;
504 int size;
505
506 if (len >= MINCLSIZE) {
507 m = m_getcl(how, type, flags);
508 size = MCLBYTES;
509 } else if (flags & M_PKTHDR) {
510 m = m_gethdr(how, type);
511 size = MHLEN;
512 } else {
513 m = m_get(how, type);
514 size = MLEN;
515 }
516 if (psize != NULL)
517 *psize = size;
518 return (m);
519}
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520
521/*
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522 * Get a single mbuf that covers the requested number of bytes.
523 * This function does not create mbuf chains. It explicitly marks
524 * places in the code that abuse mbufs for contiguous data buffers.
525 */
526static __inline struct mbuf *
527m_getb(int len, int how, int type, int flags)
528{
529 struct mbuf *m;
530 int mbufsize = (flags & M_PKTHDR) ? MHLEN : MLEN;
531
532 if (len > mbufsize)
533 m = m_getcl(how, type, flags);
534 else if (flags & M_PKTHDR)
535 m = m_gethdr(how, type);
536 else
537 m = m_get(how, type);
538 return (m);
539}
540
541/*
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542 * Packets may have annotations attached by affixing a list
543 * of "packet tags" to the pkthdr structure. Packet tags are
544 * dynamically allocated semi-opaque data structures that have
545 * a fixed header (struct m_tag) that specifies the size of the
546 * memory block and a <cookie,type> pair that identifies it.
547 * The cookie is a 32-bit unique unsigned value used to identify
548 * a module or ABI. By convention this value is chose as the
549 * date+time that the module is created, expressed as the number of
550 * seconds since the epoch (e.g. using date -u +'%s'). The type value
551 * is an ABI/module-specific value that identifies a particular annotation
552 * and is private to the module. For compatibility with systems
553 * like openbsd that define packet tags w/o an ABI/module cookie,
554 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and
555 * m_tag_find compatibility shim functions and several tag types are
556 * defined below. Users that do not require compatibility should use
557 * a private cookie value so that packet tag-related definitions
558 * can be maintained privately.
559 *
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560 * Note that the packet tag returned by m_tag_alloc has the default
561 * memory alignment implemented by kmalloc. To reference private data
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562 * one can use a construct like:
563 *
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564 * struct m_tag *mtag = m_tag_alloc(...);
565 * struct foo *p = m_tag_data(mtag);
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566 *
567 * if the alignment of struct m_tag is sufficient for referencing members
568 * of struct foo. Otherwise it is necessary to embed struct m_tag within
569 * the private data structure to insure proper alignment; e.g.
570 *
571 * struct foo {
572 * struct m_tag tag;
573 * ...
574 * };
4c7020ad 575 * struct foo *p = (struct foo *)m_tag_alloc(...);
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576 * struct m_tag *mtag = &p->tag;
577 */
578
579#define PACKET_TAG_NONE 0 /* Nadda */
580
581/* Packet tag for use with PACKET_ABI_COMPAT */
582#define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */
821819dc 583/* struct tdb_indent */
984263bc 584#define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */
821819dc 585/* struct tdb_indent */
984263bc 586#define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */
821819dc 587/* struct tdb_indent, never added */
984263bc 588#define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */
821819dc 589/* struct tdb_indent, never added */
ba3a125b 590#define PACKET_TAG_IPSEC_PENDING_TDB 5 /* Reminder to do IPsec */
821819dc 591/* struct tdb_indent, never added */
ba3a125b 592#define PACKET_TAG_ENCAP 6 /* Encap. processing */
821819dc 593/* struct ifnet *, the GIF interface */
ba3a125b 594#define PACKET_TAG_IPSEC_HISTORY 7 /* IPSEC history */
821819dc 595/* struct ipsec_history */
ba3a125b 596#define PACKET_TAG_IPV6_INPUT 8 /* IPV6 input processing */
821819dc 597/* struct ip6aux */
e5ecc832 598#define PACKET_TAG_IPFW_DIVERT 9 /* divert info */
68edaf54 599/* struct divert_info */
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600#define PACKET_TAG_DUMMYNET 15 /* dummynet info */
601/* struct dn_pkt */
984263bc 602#define PACKET_TAG_IPFORWARD 18 /* ipforward info */
5de23090 603/* struct sockaddr_in */
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604#define PACKET_TAG_IPSRCRT 27 /* IP srcrt opts */
605/* struct ip_srcrt_opt */
5de23090 606#define PACKET_TAG_CARP 28 /* CARP info */
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607
608/* Packet tag routines */
609struct m_tag *m_tag_alloc(u_int32_t, int, int, int);
610void m_tag_free(struct m_tag *);
611void m_tag_prepend(struct mbuf *, struct m_tag *);
612void m_tag_unlink(struct mbuf *, struct m_tag *);
613void m_tag_delete(struct mbuf *, struct m_tag *);
7b6f875f 614void m_tag_delete_chain(struct mbuf *);
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615struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *);
616struct m_tag *m_tag_copy(struct m_tag *, int);
f15db79e 617int m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
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618void m_tag_init(struct mbuf *);
619struct m_tag *m_tag_first(struct mbuf *);
620struct m_tag *m_tag_next(struct mbuf *, struct m_tag *);
621
622/* these are for openbsd compatibility */
623#define MTAG_ABI_COMPAT 0 /* compatibility ABI */
624
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625static __inline void *
626m_tag_data(struct m_tag *tag)
627{
628 return ((void *)(tag + 1));
629}
630
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631static __inline struct m_tag *
632m_tag_get(int type, int length, int wait)
633{
634 return m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait);
635}
636
637static __inline struct m_tag *
638m_tag_find(struct mbuf *m, int type, struct m_tag *start)
639{
640 return m_tag_locate(m, MTAG_ABI_COMPAT, type, start);
641}
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643#endif /* _KERNEL */
644
645#endif /* _KERNEL || _KERNEL_STRUCTURES */
646#endif /* !_SYS_MBUF_H_ */