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29 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95
36 /* XXX: These includes suck. Sorry! */
37 #include <sys/queue.h>
39 #include <sys/systm.h>
47 * Mbufs are of a single size, MSIZE (sys/param.h), which
48 * includes overhead. An mbuf may add a single "mbuf cluster" of size
49 * MCLBYTES (also in sys/param.h), which has no additional overhead
50 * and is used instead of the internal data area; this is done when
51 * at least MINCLSIZE of data must be stored. Additionally, it is possible
52 * to allocate a separate buffer externally and attach it to the mbuf in
53 * a way similar to that of mbuf clusters.
55 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */
56 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */
57 #define MINCLSIZE (MHLEN + 1) /* smallest amount to put in cluster */
58 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */
62 * Macros for type conversion:
63 * mtod(m, t) -- Convert mbuf pointer to data pointer of correct type.
64 * dtom(x) -- Convert data pointer within mbuf to mbuf pointer (XXX).
66 #define mtod(m, t) ((t)((m)->m_data))
67 #define dtom(x) ((struct mbuf *)((intptr_t)(x) & ~(MSIZE-1)))
70 * Argument structure passed to UMA routines during mbuf and packet
74 int flags; /* Flags for mbuf being allocated */
75 short type; /* Type of mbuf being allocated */
80 * Header present at the beginning of every mbuf.
83 struct mbuf *mh_next; /* next buffer in chain */
84 struct mbuf *mh_nextpkt; /* next chain in queue/record */
85 caddr_t mh_data; /* location of data */
86 int mh_len; /* amount of data in this mbuf */
87 int mh_flags; /* flags; see below */
88 short mh_type; /* type of data in this mbuf */
92 * Packet tag structure (see below for details).
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 void (*m_tag_free)(struct m_tag *);
103 * Record/packet header in first mbuf of chain; valid only if M_PKTHDR is set.
106 struct ifnet *rcvif; /* rcv interface */
107 int len; /* total packet length */
108 /* variables for ip and tcp reassembly */
109 void *header; /* pointer to packet header */
110 /* variables for hardware checksum */
111 int csum_flags; /* flags regarding checksum */
112 int csum_data; /* data field used by csum routines */
113 SLIST_HEAD(packet_tags, m_tag) tags; /* list of packet tags */
117 * Description of external storage mapped into mbuf; valid only if M_EXT is set.
120 caddr_t ext_buf; /* start of buffer */
121 void (*ext_free) /* free routine if not the usual */
123 void *ext_args; /* optional argument pointer */
124 u_int ext_size; /* size of buffer, for ext_free */
125 volatile u_int *ref_cnt; /* pointer to ref count info */
126 int ext_type; /* type of external storage */
130 * The core of the mbuf object along with some shortcut defines for
131 * practical purposes.
137 struct pkthdr MH_pkthdr; /* M_PKTHDR set */
139 struct m_ext MH_ext; /* M_EXT set */
140 char MH_databuf[MHLEN];
143 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */
146 #define m_next m_hdr.mh_next
147 #define m_len m_hdr.mh_len
148 #define m_data m_hdr.mh_data
149 #define m_type m_hdr.mh_type
150 #define m_flags m_hdr.mh_flags
151 #define m_nextpkt m_hdr.mh_nextpkt
152 #define m_act m_nextpkt
153 #define m_pkthdr M_dat.MH.MH_pkthdr
154 #define m_ext M_dat.MH.MH_dat.MH_ext
155 #define m_pktdat M_dat.MH.MH_dat.MH_databuf
156 #define m_dat M_dat.M_databuf
161 #define M_EXT 0x0001 /* has associated external storage */
162 #define M_PKTHDR 0x0002 /* start of record */
163 #define M_EOR 0x0004 /* end of record */
164 #define M_RDONLY 0x0008 /* associated data is marked read-only */
165 #define M_PROTO1 0x0010 /* protocol-specific */
166 #define M_PROTO2 0x0020 /* protocol-specific */
167 #define M_PROTO3 0x0040 /* protocol-specific */
168 #define M_PROTO4 0x0080 /* protocol-specific */
169 #define M_PROTO5 0x0100 /* protocol-specific */
170 #define M_SKIP_FIREWALL 0x4000 /* skip firewall processing */
171 #define M_FREELIST 0x8000 /* mbuf is on the free list */
174 * mbuf pkthdr flags (also stored in m_flags).
176 #define M_BCAST 0x0200 /* send/received as link-level broadcast */
177 #define M_MCAST 0x0400 /* send/received as link-level multicast */
178 #define M_FRAG 0x0800 /* packet is a fragment of a larger packet */
179 #define M_FIRSTFRAG 0x1000 /* packet is first fragment */
180 #define M_LASTFRAG 0x2000 /* packet is last fragment */
181 #define M_VLANTAG 0x10000 /* packet has VLAN tag attached */
184 * External buffer types: identify ext_buf type.
186 #define EXT_CLUSTER 1 /* mbuf cluster */
187 #define EXT_SFBUF 2 /* sendfile(2)'s sf_bufs */
188 #define EXT_PACKET 3 /* came out of Packet zone */
189 #define EXT_NET_DRV 100 /* custom ext_buf provided by net driver(s) */
190 #define EXT_MOD_TYPE 200 /* custom module's ext_buf type */
191 #define EXT_DISPOSABLE 300 /* can throw this buffer away w/page flipping */
192 #define EXT_EXTREF 400 /* has externally maintained ref_cnt ptr */
195 * Flags copied when copying m_pkthdr.
197 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_RDONLY|M_PROTO1|M_PROTO1|M_PROTO2|\
198 M_PROTO3|M_PROTO4|M_PROTO5|M_SKIP_FIREWALL|\
199 M_BCAST|M_MCAST|M_FRAG|M_FIRSTFRAG|M_LASTFRAG|\
203 * Flags indicating hw checksum support and sw checksum requirements.
205 #define CSUM_IP 0x0001 /* will csum IP */
206 #define CSUM_TCP 0x0002 /* will csum TCP */
207 #define CSUM_UDP 0x0004 /* will csum UDP */
208 #define CSUM_IP_FRAGS 0x0008 /* will csum IP fragments */
209 #define CSUM_FRAGMENT 0x0010 /* will do IP fragmentation */
211 #define CSUM_IP_CHECKED 0x0100 /* did csum IP */
212 #define CSUM_IP_VALID 0x0200 /* ... the csum is valid */
213 #define CSUM_DATA_VALID 0x0400 /* csum_data field is valid */
214 #define CSUM_PSEUDO_HDR 0x0800 /* csum_data has pseudo hdr */
216 #define CSUM_DELAY_DATA (CSUM_TCP | CSUM_UDP)
217 #define CSUM_DELAY_IP (CSUM_IP) /* XXX add ipv6 here too? */
222 #define MT_NOTMBUF 0 /* USED INTERNALLY ONLY! Object is not mbuf */
223 #define MT_DATA 1 /* dynamic (data) allocation */
224 #define MT_HEADER 2 /* packet header */
226 #define MT_SOCKET 3 /* socket structure */
227 #define MT_PCB 4 /* protocol control block */
228 #define MT_RTABLE 5 /* routing tables */
229 #define MT_HTABLE 6 /* IMP host tables */
230 #define MT_ATABLE 7 /* address resolution tables */
232 #define MT_SONAME 8 /* socket name */
234 #define MT_SOOPTS 10 /* socket options */
236 #define MT_FTABLE 11 /* fragment reassembly header */
238 #define MT_RIGHTS 12 /* access rights */
239 #define MT_IFADDR 13 /* interface address */
241 #define MT_CONTROL 14 /* extra-data protocol message */
242 #define MT_OOBDATA 15 /* expedited data */
243 #define MT_NTYPES 16 /* number of mbuf types for mbtypes[] */
246 * General mbuf allocator statistics structure.
249 u_long m_mbufs; /* XXX */
250 u_long m_mclusts; /* XXX */
252 u_long m_drain; /* times drained protocols for space */
253 u_long m_mcfail; /* XXX: times m_copym failed */
254 u_long m_mpfail; /* XXX: times m_pullup failed */
255 u_long m_msize; /* length of an mbuf */
256 u_long m_mclbytes; /* length of an mbuf cluster */
257 u_long m_minclsize; /* min length of data to allocate a cluster */
258 u_long m_mlen; /* length of data in an mbuf */
259 u_long m_mhlen; /* length of data in a header mbuf */
261 /* Number of mbtypes (gives # elems in mbtypes[] array: */
264 /* XXX: Sendfile stats should eventually move to their own struct */
265 u_long sf_iocnt; /* times sendfile had to do disk I/O */
266 u_long sf_allocfail; /* times sfbuf allocation failed */
267 u_long sf_allocwait; /* times sfbuf allocation had to wait */
271 * Flags specifying how an allocation should be made.
273 * The flag to use is as follows:
274 * - M_DONTWAIT or M_NOWAIT from an interrupt handler to not block allocation.
275 * - M_WAIT or M_WAITOK or M_TRYWAIT from wherever it is safe to block.
277 * M_DONTWAIT/M_NOWAIT means that we will not block the thread explicitly
278 * and if we cannot allocate immediately we may return NULL,
279 * whereas M_WAIT/M_WAITOK/M_TRYWAIT means that if we cannot allocate
280 * resources we will block until they are available, and thus never
283 * XXX Eventually just phase this out to use M_WAITOK/M_NOWAIT.
285 #define MBTOM(how) (how)
286 #define M_DONTWAIT M_NOWAIT
287 #define M_TRYWAIT M_WAITOK
288 #define M_WAIT M_WAITOK
292 * mbuf external reference count management macros.
294 * MEXT_IS_REF(m): true if (m) is not the only mbuf referencing
295 * the external buffer ext_buf.
297 * MEXT_REM_REF(m): remove reference to m_ext object.
299 * MEXT_ADD_REF(m): add reference to m_ext object already
300 * referred to by (m). XXX Note that it is VERY important that you
301 * always set the second mbuf's m_ext.ref_cnt to point to the first
302 * one's (i.e., n->m_ext.ref_cnt = m->m_ext.ref_cnt) AFTER you run
303 * MEXT_ADD_REF(m). This is because m might have a lazy initialized
304 * ref_cnt (NULL) before this is run and it will only be looked up
305 * from here. We should make MEXT_ADD_REF() always take two mbufs
306 * as arguments so that it can take care of this itself.
308 #define MEXT_IS_REF(m) (((m)->m_ext.ref_cnt != NULL) \
309 && (*((m)->m_ext.ref_cnt) > 1))
311 #define MEXT_REM_REF(m) do { \
312 KASSERT((m)->m_ext.ref_cnt != NULL, ("m_ext refcnt lazy NULL")); \
313 KASSERT(*((m)->m_ext.ref_cnt) > 0, ("m_ext refcnt < 0")); \
314 atomic_subtract_int((m)->m_ext.ref_cnt, 1); \
317 #define MEXT_ADD_REF(m) do { \
318 if ((m)->m_ext.ref_cnt == NULL) { \
319 KASSERT((m)->m_ext.ext_type == EXT_CLUSTER || \
320 (m)->m_ext.ext_type == EXT_PACKET, \
321 ("Unexpected mbuf type has lazy refcnt")); \
322 (m)->m_ext.ref_cnt = (u_int *)uma_find_refcnt( \
323 zone_clust, (m)->m_ext.ext_buf); \
324 *((m)->m_ext.ref_cnt) = 2; \
326 atomic_add_int((m)->m_ext.ref_cnt, 1); \
330 #define MBUF_CHECKSLEEP(how) do { \
331 if (how == M_WAITOK) \
332 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \
333 "Sleeping in \"%s\"", __func__); \
336 #define MBUF_CHECKSLEEP(how)
340 * Network buffer allocation API
342 * The rest of it is defined in kern/kern_mbuf.c
345 extern uma_zone_t zone_mbuf;
346 extern uma_zone_t zone_clust;
347 extern uma_zone_t zone_pack;
349 static __inline struct mbuf *m_get(int how, short type);
350 static __inline struct mbuf *m_gethdr(int how, short type);
351 static __inline struct mbuf *m_getcl(int how, short type, int flags);
352 static __inline struct mbuf *m_getclr(int how, short type); /* XXX */
353 static __inline struct mbuf *m_free(struct mbuf *m);
354 static __inline void m_clget(struct mbuf *m, int how);
355 static __inline void m_chtype(struct mbuf *m, short new_type);
356 void mb_free_ext(struct mbuf *);
360 m_get(int how, short type)
366 return (uma_zalloc_arg(zone_mbuf, &args, how));
369 /* XXX This should be depracated, very little use */
372 m_getclr(int how, short type)
379 m = uma_zalloc_arg(zone_mbuf, &args, how);
381 bzero(m->m_data, MLEN);
387 m_gethdr(int how, short type)
391 args.flags = M_PKTHDR;
393 return (uma_zalloc_arg(zone_mbuf, &args, how));
398 m_getcl(int how, short type, int flags)
404 return (uma_zalloc_arg(zone_pack, &args, how));
409 m_free(struct mbuf *m)
411 struct mbuf *n = m->m_next;
414 m->m_flags |= M_FREELIST;
416 if (m->m_flags & M_EXT)
419 uma_zfree(zone_mbuf, m);
425 m_clget(struct mbuf *m, int how)
428 m->m_ext.ext_buf = NULL;
429 uma_zalloc_arg(zone_clust, m, how);
434 m_chtype(struct mbuf *m, short new_type)
436 m->m_type = new_type;
440 * mbuf, cluster, and external object allocation macros
441 * (for compatibility purposes).
443 /* NB: M_COPY_PKTHDR is deprecated. Use M_MOVE_PKTHDR or m_dup_pktdr. */
444 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from))
445 #define MGET(m, how, type) ((m) = m_get((how), (type)))
446 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type)))
447 #define MCLGET(m, how) m_clget((m), (how))
448 #define MEXTADD(m, buf, size, free, args, flags, type) \
449 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type))
452 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this
453 * can be both the local data payload, or an external buffer area,
454 * depending on whether M_EXT is set).
456 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && (!((m)->m_flags \
457 & M_EXT) || !MEXT_IS_REF(m)))
459 /* Check if the supplied mbuf has a packet header, or else panic. */
460 #define M_ASSERTPKTHDR(m) \
461 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \
462 ("%s: no mbuf packet header!", __func__))
464 /* Ensure that the supplied mbuf is a valid, non-free mbuf. */
465 #define M_ASSERTVALID(m) \
466 KASSERT((((struct mbuf *)m)->m_flags & M_FREELIST) == 0, \
467 ("%s: attempted use of a free mbuf!", __func__))
470 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place
471 * an object of the specified size at the end of the mbuf, longword aligned.
473 #define M_ALIGN(m, len) do { \
474 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \
478 * As above, for mbufs allocated with m_gethdr/MGETHDR
479 * or initialized by M_COPY_PKTHDR.
481 #define MH_ALIGN(m, len) do { \
482 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \
486 * Compute the amount of space available
487 * before the current start of data in an mbuf.
489 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
490 * of checking writability of the mbuf data area rests solely with the caller.
492 #define M_LEADINGSPACE(m) \
493 ((m)->m_flags & M_EXT ? \
494 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \
495 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
496 (m)->m_data - (m)->m_dat)
499 * Compute the amount of space available
500 * after the end of data in an mbuf.
502 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
503 * of checking writability of the mbuf data area rests solely with the caller.
505 #define M_TRAILINGSPACE(m) \
506 ((m)->m_flags & M_EXT ? \
507 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \
508 - ((m)->m_data + (m)->m_len) : 0) : \
509 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
512 * Arrange to prepend space of size plen to mbuf m.
513 * If a new mbuf must be allocated, how specifies whether to wait.
514 * If the allocation fails, the original mbuf chain is freed and m is
517 #define M_PREPEND(m, plen, how) do { \
518 struct mbuf **_mmp = &(m); \
519 struct mbuf *_mm = *_mmp; \
520 int _mplen = (plen); \
521 int __mhow = (how); \
523 MBUF_CHECKSLEEP(how); \
524 if (M_LEADINGSPACE(_mm) >= _mplen) { \
525 _mm->m_data -= _mplen; \
526 _mm->m_len += _mplen; \
528 _mm = m_prepend(_mm, _mplen, __mhow); \
529 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \
530 _mm->m_pkthdr.len += _mplen; \
535 * Change mbuf to new type.
536 * This is a relatively expensive operation and should be avoided.
538 #define MCHTYPE(m, t) m_chtype((m), (t))
540 /* Length to m_copy to copy all. */
541 #define M_COPYALL 1000000000
543 /* Compatibility with 4.3. */
544 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT)
546 extern int max_datalen; /* MHLEN - max_hdr */
547 extern int max_hdr; /* Largest link + protocol header */
548 extern int max_linkhdr; /* Largest link-level header */
549 extern int max_protohdr; /* Largest protocol header */
550 extern struct mbstat mbstat; /* General mbuf stats/infos */
551 extern int nmbclusters; /* Maximum number of clusters */
555 void m_adj(struct mbuf *, int);
556 int m_apply(struct mbuf *, int, int,
557 int (*)(void *, void *, u_int), void *);
558 int m_append(struct mbuf *, int, c_caddr_t);
559 void m_cat(struct mbuf *, struct mbuf *);
560 void m_extadd(struct mbuf *, caddr_t, u_int,
561 void (*)(void *, void *), void *, int, int);
562 void m_copyback(struct mbuf *, int, int, c_caddr_t);
563 void m_copydata(const struct mbuf *, int, int, caddr_t);
564 struct mbuf *m_copym(struct mbuf *, int, int, int);
565 struct mbuf *m_copypacket(struct mbuf *, int);
566 void m_copy_pkthdr(struct mbuf *, struct mbuf *);
567 struct mbuf *m_defrag(struct mbuf *, int);
568 struct mbuf *m_devget(char *, int, int, struct ifnet *,
569 void (*)(char *, caddr_t, u_int));
570 struct mbuf *m_dup(struct mbuf *, int);
571 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int);
572 u_int m_fixhdr(struct mbuf *);
573 struct mbuf *m_fragment(struct mbuf *, int, int);
574 void m_freem(struct mbuf *);
575 struct mbuf *m_getm(struct mbuf *, int, int, short);
576 struct mbuf *m_getptr(struct mbuf *, int, int *);
577 u_int m_length(struct mbuf *, struct mbuf **);
578 void m_move_pkthdr(struct mbuf *, struct mbuf *);
579 struct mbuf *m_prepend(struct mbuf *, int, int);
580 void m_print(const struct mbuf *, int);
581 struct mbuf *m_pulldown(struct mbuf *, int, int, int *);
582 struct mbuf *m_pullup(struct mbuf *, int);
583 struct mbuf *m_split(struct mbuf *, int, int);
584 struct mbuf *m_uiotombuf(struct uio *, int, int);
587 * Network packets may have annotations attached by affixing a list
588 * of "packet tags" to the pkthdr structure. Packet tags are
589 * dynamically allocated semi-opaque data structures that have
590 * a fixed header (struct m_tag) that specifies the size of the
591 * memory block and a <cookie,type> pair that identifies it.
592 * The cookie is a 32-bit unique unsigned value used to identify
593 * a module or ABI. By convention this value is chose as the
594 * date+time that the module is created, expressed as the number of
595 * seconds since the epoch (e.g., using date -u +'%s'). The type value
596 * is an ABI/module-specific value that identifies a particular annotation
597 * and is private to the module. For compatibility with systems
598 * like OpenBSD that define packet tags w/o an ABI/module cookie,
599 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and
600 * m_tag_find compatibility shim functions and several tag types are
601 * defined below. Users that do not require compatibility should use
602 * a private cookie value so that packet tag-related definitions
603 * can be maintained privately.
605 * Note that the packet tag returned by m_tag_alloc has the default
606 * memory alignment implemented by malloc. To reference private data
607 * one can use a construct like:
609 * struct m_tag *mtag = m_tag_alloc(...);
610 * struct foo *p = (struct foo *)(mtag+1);
612 * if the alignment of struct m_tag is sufficient for referencing members
613 * of struct foo. Otherwise it is necessary to embed struct m_tag within
614 * the private data structure to insure proper alignment; e.g.,
620 * struct foo *p = (struct foo *) m_tag_alloc(...);
621 * struct m_tag *mtag = &p->tag;
625 * Persistent tags stay with an mbuf until the mbuf is reclaimed.
626 * Otherwise tags are expected to ``vanish'' when they pass through
627 * a network interface. For most interfaces this happens normally
628 * as the tags are reclaimed when the mbuf is free'd. However in
629 * some special cases reclaiming must be done manually. An example
630 * is packets that pass through the loopback interface. Also, one
631 * must be careful to do this when ``turning around'' packets (e.g.,
634 * To mark a tag persistent bit-or this flag in when defining the
635 * tag id. The tag will then be treated as described above.
637 #define MTAG_PERSISTENT 0x800
639 #define PACKET_TAG_NONE 0 /* Nadda */
641 /* Packet tags for use with PACKET_ABI_COMPAT. */
642 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */
643 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */
644 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */
645 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */
646 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */
647 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */
648 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */
649 #define PACKET_TAG_GIF 8 /* GIF processing done */
650 #define PACKET_TAG_GRE 9 /* GRE processing done */
651 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */
652 #define PACKET_TAG_ENCAP 11 /* Encap. processing */
653 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */
654 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */
655 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */
656 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */
657 #define PACKET_TAG_DIVERT 17 /* divert info */
658 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */
659 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */
660 #define PACKET_TAG_PF_ROUTED 21 /* PF routed, avoid loops */
661 #define PACKET_TAG_PF_FRAGCACHE 22 /* PF fragment cached */
662 #define PACKET_TAG_PF_QID 23 /* PF ALTQ queue id */
663 #define PACKET_TAG_PF_TAG 24 /* PF tagged */
664 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */
665 #define PACKET_TAG_PF_TRANSLATE_LOCALHOST 26 /* PF translate localhost */
666 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */
667 #define PACKET_TAG_CARP 28 /* CARP info */
669 /* Packet tag routines. */
670 struct m_tag *m_tag_alloc(u_int32_t, int, int, int);
671 void m_tag_delete(struct mbuf *, struct m_tag *);
672 void m_tag_delete_chain(struct mbuf *, struct m_tag *);
673 void m_tag_free_default(struct m_tag *);
674 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *);
675 struct m_tag *m_tag_copy(struct m_tag *, int);
676 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int);
677 void m_tag_delete_nonpersistent(struct mbuf *);
680 * Initialize the list of tags associated with an mbuf.
683 m_tag_init(struct mbuf *m)
685 SLIST_INIT(&m->m_pkthdr.tags);
689 * Set up the contents of a tag. Note that this does not
690 * fill in the free method; the caller is expected to do that.
692 * XXX probably should be called m_tag_init, but that was
696 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len)
700 t->m_tag_cookie = cookie;
704 * Reclaim resources associated with a tag.
707 m_tag_free(struct m_tag *t)
713 * Return the first tag associated with an mbuf.
715 static __inline struct m_tag *
716 m_tag_first(struct mbuf *m)
718 return (SLIST_FIRST(&m->m_pkthdr.tags));
722 * Return the next tag in the list of tags associated with an mbuf.
724 static __inline struct m_tag *
725 m_tag_next(struct mbuf *m, struct m_tag *t)
727 return (SLIST_NEXT(t, m_tag_link));
731 * Prepend a tag to the list of tags associated with an mbuf.
734 m_tag_prepend(struct mbuf *m, struct m_tag *t)
736 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
740 * Unlink a tag from the list of tags associated with an mbuf.
743 m_tag_unlink(struct mbuf *m, struct m_tag *t)
745 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
748 /* These are for OpenBSD compatibility. */
749 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */
751 static __inline struct m_tag *
752 m_tag_get(int type, int length, int wait)
754 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
757 static __inline struct m_tag *
758 m_tag_find(struct mbuf *m, int type, struct m_tag *start)
760 return (SLIST_EMPTY(&m->m_pkthdr.tags) ?
761 NULL : m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
766 #endif /* !_SYS_MBUF_H_ */