Bring CARP into the tree. CARP = Common Address Redundancy Protocol, which
[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 $
0d16ba1d 37 * $DragonFly: src/sys/sys/mbuf.h,v 1.41 2007/08/16 20:03:54 dillon 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 */
86 short mh_type; /* type of data in this mbuf */
87 short mh_flags; /* flags; see below */
6aad077d 88 struct netmsg_packet mh_netmsg; /* hardware->proto stack msg */
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89};
90
91/*
92 * Packet tag structure (see below for details).
93 */
94struct m_tag {
95 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */
96 u_int16_t m_tag_id; /* Tag ID */
97 u_int16_t m_tag_len; /* Length of data */
98 u_int32_t m_tag_cookie; /* ABI/Module ID */
99};
100
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101SLIST_HEAD(packet_tags, m_tag);
102
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103/*
104 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
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105 *
106 * Be careful: The fields have been carefully ordered to avoid hidden padding.
107 * Keep this in mind, when adding or removing fields!
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108 */
109struct pkthdr {
110 struct ifnet *rcvif; /* rcv interface */
111 int len; /* total packet length */
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112 struct packet_tags tags; /* list of packet tags */
113
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114 /* variables for ip and tcp reassembly */
115 void *header; /* pointer to packet header */
46ca7d86 116
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117 /* variables for hardware checksum */
118 int csum_flags; /* flags regarding checksum */
119 int csum_data; /* data field used by csum routines */
46ca7d86 120
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121 /* firewall flags */
122 uint32_t fw_flags; /* flags for PF */
123
02742ec6 124 /* variables for PF processing */
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125 uint16_t pf_tag; /* PF tag id */
126 uint8_t pf_routed; /* PF routing counter */
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127
128 /* variables for ALTQ processing */
129 uint8_t ecn_af; /* address family for ECN */
130 uint32_t altq_qid; /* queue id */
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131};
132
133/*
134 * Description of external storage mapped into mbuf; valid only if M_EXT is set.
135 */
136struct m_ext {
137 caddr_t ext_buf; /* start of buffer */
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138 void (*ext_free)(void *);
139 u_int ext_size; /* size of buffer, for ext_free */
140 void (*ext_ref)(void *);
7eccf245 141 void *ext_arg;
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142};
143
144/*
145 * The core of the mbuf object along with some shortcut defines for
146 * practical purposes.
147 */
148struct mbuf {
149 struct m_hdr m_hdr;
150 union {
151 struct {
152 struct pkthdr MH_pkthdr; /* M_PKTHDR set */
153 union {
154 struct m_ext MH_ext; /* M_EXT set */
155 char MH_databuf[MHLEN];
156 } MH_dat;
157 } MH;
158 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */
159 } M_dat;
160};
161#define m_next m_hdr.mh_next
162#define m_len m_hdr.mh_len
163#define m_data m_hdr.mh_data
164#define m_type m_hdr.mh_type
165#define m_flags m_hdr.mh_flags
166#define m_nextpkt m_hdr.mh_nextpkt
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167#define m_pkthdr M_dat.MH.MH_pkthdr
168#define m_ext M_dat.MH.MH_dat.MH_ext
169#define m_pktdat M_dat.MH.MH_dat.MH_databuf
170#define m_dat M_dat.M_databuf
171
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172/*
173 * Code that uses m_act should be converted to use m_nextpkt
174 * instead; m_act is historical and deprecated.
175 */
176#define m_act m_nextpkt
177
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178/*
179 * mbuf flags.
180 */
181#define M_EXT 0x0001 /* has associated external storage */
182#define M_PKTHDR 0x0002 /* start of record */
183#define M_EOR 0x0004 /* end of record */
184#define M_PROTO1 0x0008 /* protocol-specific */
185#define M_PROTO2 0x0010 /* protocol-specific */
186#define M_PROTO3 0x0020 /* protocol-specific */
187#define M_PROTO4 0x0040 /* protocol-specific */
188#define M_PROTO5 0x0080 /* protocol-specific */
189
190/*
191 * mbuf pkthdr flags (also stored in m_flags).
192 */
193#define M_BCAST 0x0100 /* send/received as link-level broadcast */
194#define M_MCAST 0x0200 /* send/received as link-level multicast */
195#define M_FRAG 0x0400 /* packet is a fragment of a larger packet */
196#define M_FIRSTFRAG 0x0800 /* packet is first fragment */
197#define M_LASTFRAG 0x1000 /* packet is last fragment */
77e294a1 198#define M_CLCACHE 0x2000 /* mbuf allocated from the cluster cache */
90775e29 199#define M_EXT_CLUSTER 0x4000 /* standard cluster else special */
77e294a1 200#define M_PHCACHE 0x8000 /* mbuf allocated from the pkt header cache */
78812139 201#define M_NOTIFICATION 0x10000 /* notification event */
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202
203/*
204 * Flags copied when copying m_pkthdr.
205 */
206#define M_COPYFLAGS (M_PKTHDR|M_EOR|M_PROTO1|M_PROTO1|M_PROTO2|M_PROTO3 | \
207 M_PROTO4|M_PROTO5|M_BCAST|M_MCAST|M_FRAG | \
208 M_FIRSTFRAG|M_LASTFRAG)
209
210/*
211 * Flags indicating hw checksum support and sw checksum requirements.
212 */
213#define CSUM_IP 0x0001 /* will csum IP */
214#define CSUM_TCP 0x0002 /* will csum TCP */
215#define CSUM_UDP 0x0004 /* will csum UDP */
216#define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */
217#define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */
218
219#define CSUM_IP_CHECKED 0x0100 /* did csum IP */
220#define CSUM_IP_VALID 0x0200 /* ... the csum is valid */
221#define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */
222#define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */
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223#define CSUM_FRAG_NOT_CHECKED 0x1000 /* did _not_ csum fragment
224 * NB: This flag is only used
225 * by IP defragmenter.
226 */
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227
228#define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP)
229#define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */
230
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231/*
232 * Flags indicating PF processing status
233 */
234#define PF_MBUF_GENERATED 0x00000001
235#define PF_MBUF_TAGGED 0x00000002 /* pf_tag field is valid */
236#define PF_MBUF_ROUTED 0x00000004 /* pf_routed field is valid */
237#define PF_MBUF_TRANSLATE_LOCALHOST \
238 0x00000008
239#define PF_MBUF_FRAGCACHE 0x00000010
4d723e5a 240#define ALTQ_MBUF_TAGGED 0x00000020 /* altq_qid is valid */
9bce005e 241#define IPFW_MBUF_SKIP_FIREWALL 0x00000040
02742ec6 242
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243/*
244 * mbuf types.
245 */
246#define MT_FREE 0 /* should be on free list */
247#define MT_DATA 1 /* dynamic (data) allocation */
248#define MT_HEADER 2 /* packet header */
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249#define MT_SONAME 3 /* socket name */
250#define MT_TAG 4 /* volatile metadata associated to pkts */
251#define MT_CONTROL 5 /* extra-data protocol message */
252#define MT_OOBDATA 6 /* expedited data */
253#define MT_NTYPES 7 /* number of mbuf types for mbtypes[] */
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254
255/*
256 * General mbuf allocator statistics structure.
257 */
258struct mbstat {
259 u_long m_mbufs; /* mbufs obtained from page pool */
260 u_long m_clusters; /* clusters obtained from page pool */
261 u_long m_spare; /* spare field */
262 u_long m_clfree; /* free clusters */
263 u_long m_drops; /* times failed to find space */
264 u_long m_wait; /* times waited for space */
265 u_long m_drain; /* times drained protocols for space */
266 u_long m_mcfail; /* times m_copym failed */
267 u_long m_mpfail; /* times m_pullup failed */
268 u_long m_msize; /* length of an mbuf */
269 u_long m_mclbytes; /* length of an mbuf cluster */
270 u_long m_minclsize; /* min length of data to allocate a cluster */
271 u_long m_mlen; /* length of data in an mbuf */
272 u_long m_mhlen; /* length of data in a header mbuf */
273};
274
275/*
276 * Flags specifying how an allocation should be made.
277 */
278
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279#define MB_DONTWAIT 0x4
280#define MB_TRYWAIT 0x8
281#define MB_WAIT MB_TRYWAIT
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282
283/*
284 * Mbuf to Malloc Flag Conversion.
285 */
74f1caca 286#define MBTOM(how) ((how) & MB_TRYWAIT ? M_WAITOK : M_NOWAIT)
984263bc 287
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288/*
289 * These are identifying numbers passed to the m_mballoc_wait function,
290 * allowing us to determine whether the call came from an MGETHDR or
291 * an MGET.
292 */
293#define MGETHDR_C 1
294#define MGET_C 2
295
984263bc 296/*
12496bdf 297 * mbuf allocation/deallocation macros (YYY deprecated, too big):
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298 *
299 * MGET(struct mbuf *m, int how, int type)
300 * allocates an mbuf and initializes it to contain internal data.
301 *
302 * MGETHDR(struct mbuf *m, int how, int type)
303 * allocates an mbuf and initializes it to contain a packet header
304 * and internal data.
305 */
306#define MGET(m, how, type) do { \
12496bdf 307 (m) = m_get((how), (type)); \
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308} while (0)
309
310#define MGETHDR(m, how, type) do { \
12496bdf 311 (m) = m_gethdr((how), (type)); \
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312} while (0)
313
314/*
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315 * MCLGET adds such clusters to a normal mbuf. The flag M_EXT is set upon
316 * success.
50503f0f 317 * Deprecated. Use m_getcl() or m_getl() instead.
984263bc 318 */
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319#define MCLGET(m, how) do { \
320 m_mclget((m), (how)); \
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321} while (0)
322
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323/*
324 * NB: M_COPY_PKTHDR is deprecated; use either M_MOVE_PKTHDR
325 * or m_dup_pkthdr.
326 */
327/*
328 * Move mbuf pkthdr from "from" to "to".
329 * from should have M_PKTHDR set, and to must be empty.
330 * from no longer has a pkthdr after this operation.
331 */
332#define M_MOVE_PKTHDR(_to, _from) m_move_pkthdr((_to), (_from))
333
334/*
335 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place
336 * an object of the specified size at the end of the mbuf, longword aligned.
337 */
338#define M_ALIGN(m, len) do { \
339 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \
340} while (0)
341
342/*
343 * As above, for mbufs allocated with m_gethdr/MGETHDR
344 * or initialized by M_COPY_PKTHDR.
345 */
346#define MH_ALIGN(m, len) do { \
347 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \
348} while (0)
349
350/*
351 * Check if we can write to an mbuf.
352 */
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353#define M_EXT_WRITABLE(m) (m_sharecount(m) == 1)
354#define M_WRITABLE(m) (!((m)->m_flags & M_EXT) || M_EXT_WRITABLE(m))
984263bc 355
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356/*
357 * Check if the supplied mbuf has a packet header, or else panic.
358 */
359#define M_ASSERTPKTHDR(m) \
360 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \
361 ("%s: invalid mbuf or no mbuf packet header!", __func__))
362
984263bc 363/*
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364 * Compute the amount of space available before the current start of data.
365 * The M_EXT_WRITABLE() is a temporary, conservative safety measure: the burden
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366 * of checking writability of the mbuf data area rests solely with the caller.
367 */
368#define M_LEADINGSPACE(m) \
369 ((m)->m_flags & M_EXT ? \
370 (M_EXT_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \
371 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
372 (m)->m_data - (m)->m_dat)
373
374/*
7b6f875f 375 * Compute the amount of space available after the end of data in an mbuf.
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376 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
377 * of checking writability of the mbuf data area rests solely with the caller.
378 */
379#define M_TRAILINGSPACE(m) \
380 ((m)->m_flags & M_EXT ? \
381 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \
382 - ((m)->m_data + (m)->m_len) : 0) : \
383 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
384
385/*
386 * Arrange to prepend space of size plen to mbuf m.
387 * If a new mbuf must be allocated, how specifies whether to wait.
74f1caca 388 * If how is MB_DONTWAIT and allocation fails, the original mbuf chain
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389 * is freed and m is set to NULL.
390 */
391#define M_PREPEND(m, plen, how) do { \
392 struct mbuf **_mmp = &(m); \
393 struct mbuf *_mm = *_mmp; \
394 int _mplen = (plen); \
395 int __mhow = (how); \
396 \
397 if (M_LEADINGSPACE(_mm) >= _mplen) { \
398 _mm->m_data -= _mplen; \
399 _mm->m_len += _mplen; \
400 } else \
401 _mm = m_prepend(_mm, _mplen, __mhow); \
402 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \
403 _mm->m_pkthdr.len += _mplen; \
404 *_mmp = _mm; \
405} while (0)
406
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407/* Length to m_copy to copy all. */
408#define M_COPYALL 1000000000
409
410/* Compatibility with 4.3 */
74f1caca 411#define m_copy(m, o, l) m_copym((m), (o), (l), MB_DONTWAIT)
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412
413#ifdef _KERNEL
414extern u_int m_clalloc_wid; /* mbuf cluster wait count */
415extern u_int m_mballoc_wid; /* mbuf wait count */
416extern int max_linkhdr; /* largest link-level header */
417extern int max_protohdr; /* largest protocol header */
418extern int max_hdr; /* largest link+protocol header */
419extern int max_datalen; /* MHLEN - max_hdr */
984263bc 420extern int mbuf_wait; /* mbuf sleep time */
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421extern int nmbclusters;
422extern int nmbufs;
984263bc 423
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424struct uio;
425
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426void m_adj(struct mbuf *, int);
427void m_cat(struct mbuf *, struct mbuf *);
df80f2ea 428u_int m_countm(struct mbuf *m, struct mbuf **lastm, u_int *mbcnt);
984263bc 429void m_copyback(struct mbuf *, int, int, caddr_t);
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430void m_copydata(const struct mbuf *, int, int, caddr_t);
431struct mbuf *m_copym(const struct mbuf *, int, int, int);
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432struct mbuf *m_copypacket(struct mbuf *, int);
433struct mbuf *m_defrag(struct mbuf *, int);
c8f5127a 434struct mbuf *m_defrag_nofree(struct mbuf *, int);
984263bc 435struct mbuf *m_devget(char *, int, int, struct ifnet *,
50503f0f 436 void (*copy)(volatile const void *, volatile void *, size_t));
984263bc 437struct mbuf *m_dup(struct mbuf *, int);
f15db79e 438int m_dup_pkthdr(struct mbuf *, const struct mbuf *, int);
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439struct mbuf *m_free(struct mbuf *);
440void m_freem(struct mbuf *);
441struct mbuf *m_get(int, int);
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442struct mbuf *m_getc(int len, int how, int type);
443struct mbuf *m_getcl(int how, short type, int flags);
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444struct mbuf *m_getclr(int, int);
445struct mbuf *m_gethdr(int, int);
446struct mbuf *m_getm(struct mbuf *, int, int, int);
50503f0f 447struct mbuf *m_last(struct mbuf *m);
df80f2ea 448u_int m_lengthm(struct mbuf *m, struct mbuf **lastm);
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449void m_move_pkthdr(struct mbuf *, struct mbuf *);
450struct mbuf *m_prepend(struct mbuf *, int, int);
451void m_print(const struct mbuf *m);
452struct mbuf *m_pulldown(struct mbuf *, int, int, int *);
453struct mbuf *m_pullup(struct mbuf *, int);
984263bc 454struct mbuf *m_split(struct mbuf *, int, int);
e12241e1 455struct mbuf *m_uiomove(struct uio *);
b6650ec0 456void m_mclget(struct mbuf *m, int how);
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457int m_sharecount(struct mbuf *m);
458void m_chtype(struct mbuf *m, int type);
459
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460#ifdef MBUF_DEBUG
461void mbuftrackid(struct mbuf *, int);
462#else
463#define mbuftrackid(m, id) /* empty */
464#endif
465
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466/*
467 * Allocate the right type of mbuf for the desired total length.
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468 * The mbuf returned does not necessarily cover the entire requested length.
469 * This function follows mbuf chaining policy of allowing MINCLSIZE
470 * amount of chained mbufs.
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471 */
472static __inline struct mbuf *
473m_getl(int len, int how, int type, int flags, int *psize)
474{
475 struct mbuf *m;
476 int size;
477
478 if (len >= MINCLSIZE) {
479 m = m_getcl(how, type, flags);
480 size = MCLBYTES;
481 } else if (flags & M_PKTHDR) {
482 m = m_gethdr(how, type);
483 size = MHLEN;
484 } else {
485 m = m_get(how, type);
486 size = MLEN;
487 }
488 if (psize != NULL)
489 *psize = size;
490 return (m);
491}
984263bc 492
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493/*
494 * Get a single mbuf that covers the requested number of bytes.
495 * This function does not create mbuf chains. It explicitly marks
496 * places in the code that abuse mbufs for contiguous data buffers.
497 */
498static __inline struct mbuf *
499m_getb(int len, int how, int type, int flags)
500{
501 struct mbuf *m;
502 int mbufsize = (flags & M_PKTHDR) ? MHLEN : MLEN;
503
504 if (len > mbufsize)
505 m = m_getcl(how, type, flags);
506 else if (flags & M_PKTHDR)
507 m = m_gethdr(how, type);
508 else
509 m = m_get(how, type);
510 return (m);
511}
512
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513/*
514 * Packets may have annotations attached by affixing a list
515 * of "packet tags" to the pkthdr structure. Packet tags are
516 * dynamically allocated semi-opaque data structures that have
517 * a fixed header (struct m_tag) that specifies the size of the
518 * memory block and a <cookie,type> pair that identifies it.
519 * The cookie is a 32-bit unique unsigned value used to identify
520 * a module or ABI. By convention this value is chose as the
521 * date+time that the module is created, expressed as the number of
522 * seconds since the epoch (e.g. using date -u +'%s'). The type value
523 * is an ABI/module-specific value that identifies a particular annotation
524 * and is private to the module. For compatibility with systems
525 * like openbsd that define packet tags w/o an ABI/module cookie,
526 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and
527 * m_tag_find compatibility shim functions and several tag types are
528 * defined below. Users that do not require compatibility should use
529 * a private cookie value so that packet tag-related definitions
530 * can be maintained privately.
531 *
532 * Note that the packet tag returned by m_tag_allocate has the default
533 * memory alignment implemented by malloc. To reference private data
534 * one can use a construct like:
535 *
536 * struct m_tag *mtag = m_tag_allocate(...);
537 * struct foo *p = (struct foo *)(mtag+1);
538 *
539 * if the alignment of struct m_tag is sufficient for referencing members
540 * of struct foo. Otherwise it is necessary to embed struct m_tag within
541 * the private data structure to insure proper alignment; e.g.
542 *
543 * struct foo {
544 * struct m_tag tag;
545 * ...
546 * };
547 * struct foo *p = (struct foo *) m_tag_allocate(...);
548 * struct m_tag *mtag = &p->tag;
549 */
550
551#define PACKET_TAG_NONE 0 /* Nadda */
552
553/* Packet tag for use with PACKET_ABI_COMPAT */
554#define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */
821819dc 555/* struct tdb_indent */
984263bc 556#define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */
821819dc 557/* struct tdb_indent */
984263bc 558#define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */
821819dc 559/* struct tdb_indent, never added */
984263bc 560#define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */
821819dc 561/* struct tdb_indent, never added */
ba3a125b 562#define PACKET_TAG_IPSEC_PENDING_TDB 5 /* Reminder to do IPsec */
821819dc 563/* struct tdb_indent, never added */
ba3a125b 564#define PACKET_TAG_ENCAP 6 /* Encap. processing */
821819dc 565/* struct ifnet *, the GIF interface */
ba3a125b 566#define PACKET_TAG_IPSEC_HISTORY 7 /* IPSEC history */
821819dc 567/* struct ipsec_history */
ba3a125b 568#define PACKET_TAG_IPV6_INPUT 8 /* IPV6 input processing */
821819dc 569/* struct ip6aux */
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570#define PACKET_TAG_IPFW_DIVERT 9 /* divert info */
571/* uint16_t */
0d16ba1d 572#define PACKET_TAG_CARP 28 /* CARP info */
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573
574/*
575 * As a temporary and low impact solution to replace the even uglier
576 * approach used so far in some parts of the network stack (which relies
577 * on global variables), packet tag-like annotations are stored in MT_TAG
578 * mbufs (or lookalikes) prepended to the actual mbuf chain.
579 *
580 * m_type = MT_TAG
581 * m_flags = m_tag_id
582 * m_next = next buffer in chain.
583 *
584 * BE VERY CAREFUL not to pass these blocks to the mbuf handling routines.
585 */
586#define _m_tag_id m_hdr.mh_flags
587
588/* Packet tags used in the FreeBSD network stack */
589#define PACKET_TAG_DUMMYNET 15 /* dummynet info */
821819dc 590/* struct dn_pkt as fake mbuf */
984263bc 591#define PACKET_TAG_IPFORWARD 18 /* ipforward info */
821819dc 592/* struct sockaddr_in * as m_data */
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593
594/* Packet tag routines */
595struct m_tag *m_tag_alloc(u_int32_t, int, int, int);
596void m_tag_free(struct m_tag *);
597void m_tag_prepend(struct mbuf *, struct m_tag *);
598void m_tag_unlink(struct mbuf *, struct m_tag *);
599void m_tag_delete(struct mbuf *, struct m_tag *);
7b6f875f 600void m_tag_delete_chain(struct mbuf *);
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601struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *);
602struct m_tag *m_tag_copy(struct m_tag *, int);
f15db79e 603int m_tag_copy_chain(struct mbuf *, const struct mbuf *, int);
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604void m_tag_init(struct mbuf *);
605struct m_tag *m_tag_first(struct mbuf *);
606struct m_tag *m_tag_next(struct mbuf *, struct m_tag *);
607
608/* these are for openbsd compatibility */
609#define MTAG_ABI_COMPAT 0 /* compatibility ABI */
610
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611static __inline void *
612m_tag_data(struct m_tag *tag)
613{
614 return ((void *)(tag + 1));
615}
616
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617static __inline struct m_tag *
618m_tag_get(int type, int length, int wait)
619{
620 return m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait);
621}
622
623static __inline struct m_tag *
624m_tag_find(struct mbuf *m, int type, struct m_tag *start)
625{
626 return m_tag_locate(m, MTAG_ABI_COMPAT, type, start);
627}
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629#endif /* _KERNEL */
630
631#endif /* _KERNEL || _KERNEL_STRUCTURES */
632#endif /* !_SYS_MBUF_H_ */