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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
291 * String names of mbuf-related UMA(9) and malloc(9) types. Exposed to
292 * !_KERNEL so that monitoring tools can look up the zones with
295 #define MBUF_MEM_NAME "mbuf"
296 #define MBUF_CLUSTER_MEM_NAME "mbuf_cluster"
297 #define MBUF_PACKET_MEM_NAME "mbuf_packet"
298 #define MBUF_TAG_MEM_NAME "mbuf_tag"
302 * mbuf external reference count management macros.
304 * MEXT_IS_REF(m): true if (m) is not the only mbuf referencing
305 * the external buffer ext_buf.
307 * MEXT_REM_REF(m): remove reference to m_ext object.
309 * MEXT_ADD_REF(m): add reference to m_ext object already
310 * referred to by (m). XXX Note that it is VERY important that you
311 * always set the second mbuf's m_ext.ref_cnt to point to the first
312 * one's (i.e., n->m_ext.ref_cnt = m->m_ext.ref_cnt) AFTER you run
313 * MEXT_ADD_REF(m). This is because m might have a lazy initialized
314 * ref_cnt (NULL) before this is run and it will only be looked up
315 * from here. We should make MEXT_ADD_REF() always take two mbufs
316 * as arguments so that it can take care of this itself.
318 #define MEXT_IS_REF(m) (((m)->m_ext.ref_cnt != NULL) \
319 && (*((m)->m_ext.ref_cnt) > 1))
321 #define MEXT_REM_REF(m) do { \
322 KASSERT((m)->m_ext.ref_cnt != NULL, ("m_ext refcnt lazy NULL")); \
323 KASSERT(*((m)->m_ext.ref_cnt) > 0, ("m_ext refcnt < 0")); \
324 atomic_subtract_int((m)->m_ext.ref_cnt, 1); \
327 #define MEXT_ADD_REF(m) do { \
328 if ((m)->m_ext.ref_cnt == NULL) { \
329 KASSERT((m)->m_ext.ext_type == EXT_CLUSTER || \
330 (m)->m_ext.ext_type == EXT_PACKET, \
331 ("Unexpected mbuf type has lazy refcnt")); \
332 (m)->m_ext.ref_cnt = (u_int *)uma_find_refcnt( \
333 zone_clust, (m)->m_ext.ext_buf); \
334 *((m)->m_ext.ref_cnt) = 2; \
336 atomic_add_int((m)->m_ext.ref_cnt, 1); \
340 #define MBUF_CHECKSLEEP(how) do { \
341 if (how == M_WAITOK) \
342 WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, \
343 "Sleeping in \"%s\"", __func__); \
346 #define MBUF_CHECKSLEEP(how)
350 * Network buffer allocation API
352 * The rest of it is defined in kern/kern_mbuf.c
355 extern uma_zone_t zone_mbuf;
356 extern uma_zone_t zone_clust;
357 extern uma_zone_t zone_pack;
359 static __inline struct mbuf *m_get(int how, short type);
360 static __inline struct mbuf *m_gethdr(int how, short type);
361 static __inline struct mbuf *m_getcl(int how, short type, int flags);
362 static __inline struct mbuf *m_getclr(int how, short type); /* XXX */
363 static __inline struct mbuf *m_free(struct mbuf *m);
364 static __inline void m_clget(struct mbuf *m, int how);
365 static __inline void m_chtype(struct mbuf *m, short new_type);
366 void mb_free_ext(struct mbuf *);
370 m_get(int how, short type)
376 return (uma_zalloc_arg(zone_mbuf, &args, how));
379 /* XXX This should be depracated, very little use */
382 m_getclr(int how, short type)
389 m = uma_zalloc_arg(zone_mbuf, &args, how);
391 bzero(m->m_data, MLEN);
397 m_gethdr(int how, short type)
401 args.flags = M_PKTHDR;
403 return (uma_zalloc_arg(zone_mbuf, &args, how));
408 m_getcl(int how, short type, int flags)
414 return (uma_zalloc_arg(zone_pack, &args, how));
419 m_free(struct mbuf *m)
421 struct mbuf *n = m->m_next;
424 m->m_flags |= M_FREELIST;
426 if (m->m_flags & M_EXT)
429 uma_zfree(zone_mbuf, m);
435 m_clget(struct mbuf *m, int how)
438 m->m_ext.ext_buf = NULL;
439 uma_zalloc_arg(zone_clust, m, how);
444 m_chtype(struct mbuf *m, short new_type)
446 m->m_type = new_type;
450 * mbuf, cluster, and external object allocation macros
451 * (for compatibility purposes).
453 /* NB: M_COPY_PKTHDR is deprecated. Use M_MOVE_PKTHDR or m_dup_pktdr. */
454 #define M_MOVE_PKTHDR(to, from) m_move_pkthdr((to), (from))
455 #define MGET(m, how, type) ((m) = m_get((how), (type)))
456 #define MGETHDR(m, how, type) ((m) = m_gethdr((how), (type)))
457 #define MCLGET(m, how) m_clget((m), (how))
458 #define MEXTADD(m, buf, size, free, args, flags, type) \
459 m_extadd((m), (caddr_t)(buf), (size), (free), (args), (flags), (type))
462 * Evaluate TRUE if it's safe to write to the mbuf m's data region (this
463 * can be both the local data payload, or an external buffer area,
464 * depending on whether M_EXT is set).
466 #define M_WRITABLE(m) (!((m)->m_flags & M_RDONLY) && (!((m)->m_flags \
467 & M_EXT) || !MEXT_IS_REF(m)))
469 /* Check if the supplied mbuf has a packet header, or else panic. */
470 #define M_ASSERTPKTHDR(m) \
471 KASSERT(m != NULL && m->m_flags & M_PKTHDR, \
472 ("%s: no mbuf packet header!", __func__))
474 /* Ensure that the supplied mbuf is a valid, non-free mbuf. */
475 #define M_ASSERTVALID(m) \
476 KASSERT((((struct mbuf *)m)->m_flags & M_FREELIST) == 0, \
477 ("%s: attempted use of a free mbuf!", __func__))
480 * Set the m_data pointer of a newly-allocated mbuf (m_get/MGET) to place
481 * an object of the specified size at the end of the mbuf, longword aligned.
483 #define M_ALIGN(m, len) do { \
484 (m)->m_data += (MLEN - (len)) & ~(sizeof(long) - 1); \
488 * As above, for mbufs allocated with m_gethdr/MGETHDR
489 * or initialized by M_COPY_PKTHDR.
491 #define MH_ALIGN(m, len) do { \
492 (m)->m_data += (MHLEN - (len)) & ~(sizeof(long) - 1); \
496 * Compute the amount of space available
497 * before the current start of data in an mbuf.
499 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
500 * of checking writability of the mbuf data area rests solely with the caller.
502 #define M_LEADINGSPACE(m) \
503 ((m)->m_flags & M_EXT ? \
504 (M_WRITABLE(m) ? (m)->m_data - (m)->m_ext.ext_buf : 0): \
505 (m)->m_flags & M_PKTHDR ? (m)->m_data - (m)->m_pktdat : \
506 (m)->m_data - (m)->m_dat)
509 * Compute the amount of space available
510 * after the end of data in an mbuf.
512 * The M_WRITABLE() is a temporary, conservative safety measure: the burden
513 * of checking writability of the mbuf data area rests solely with the caller.
515 #define M_TRAILINGSPACE(m) \
516 ((m)->m_flags & M_EXT ? \
517 (M_WRITABLE(m) ? (m)->m_ext.ext_buf + (m)->m_ext.ext_size \
518 - ((m)->m_data + (m)->m_len) : 0) : \
519 &(m)->m_dat[MLEN] - ((m)->m_data + (m)->m_len))
522 * Arrange to prepend space of size plen to mbuf m.
523 * If a new mbuf must be allocated, how specifies whether to wait.
524 * If the allocation fails, the original mbuf chain is freed and m is
527 #define M_PREPEND(m, plen, how) do { \
528 struct mbuf **_mmp = &(m); \
529 struct mbuf *_mm = *_mmp; \
530 int _mplen = (plen); \
531 int __mhow = (how); \
533 MBUF_CHECKSLEEP(how); \
534 if (M_LEADINGSPACE(_mm) >= _mplen) { \
535 _mm->m_data -= _mplen; \
536 _mm->m_len += _mplen; \
538 _mm = m_prepend(_mm, _mplen, __mhow); \
539 if (_mm != NULL && _mm->m_flags & M_PKTHDR) \
540 _mm->m_pkthdr.len += _mplen; \
545 * Change mbuf to new type.
546 * This is a relatively expensive operation and should be avoided.
548 #define MCHTYPE(m, t) m_chtype((m), (t))
550 /* Length to m_copy to copy all. */
551 #define M_COPYALL 1000000000
553 /* Compatibility with 4.3. */
554 #define m_copy(m, o, l) m_copym((m), (o), (l), M_DONTWAIT)
556 extern int max_datalen; /* MHLEN - max_hdr */
557 extern int max_hdr; /* Largest link + protocol header */
558 extern int max_linkhdr; /* Largest link-level header */
559 extern int max_protohdr; /* Largest protocol header */
560 extern struct mbstat mbstat; /* General mbuf stats/infos */
561 extern int nmbclusters; /* Maximum number of clusters */
565 void m_adj(struct mbuf *, int);
566 void m_align(struct mbuf *, int);
567 int m_apply(struct mbuf *, int, int,
568 int (*)(void *, void *, u_int), void *);
569 int m_append(struct mbuf *, int, c_caddr_t);
570 void m_cat(struct mbuf *, struct mbuf *);
571 void m_extadd(struct mbuf *, caddr_t, u_int,
572 void (*)(void *, void *), void *, int, int);
573 void m_copyback(struct mbuf *, int, int, c_caddr_t);
574 void m_copydata(const struct mbuf *, int, int, caddr_t);
575 struct mbuf *m_copym(struct mbuf *, int, int, int);
576 struct mbuf *m_copymdata(struct mbuf *, struct mbuf *,
578 struct mbuf *m_copypacket(struct mbuf *, int);
579 void m_copy_pkthdr(struct mbuf *, struct mbuf *);
580 struct mbuf *m_copyup(struct mbuf *n, int len, int dstoff);
581 struct mbuf *m_defrag(struct mbuf *, int);
582 void m_demote(struct mbuf *);
583 struct mbuf *m_devget(char *, int, int, struct ifnet *,
584 void (*)(char *, caddr_t, u_int));
585 struct mbuf *m_dup(struct mbuf *, int);
586 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int);
587 u_int m_fixhdr(struct mbuf *);
588 struct mbuf *m_fragment(struct mbuf *, int, int);
589 void m_freem(struct mbuf *);
590 struct mbuf *m_getm(struct mbuf *, int, int, short);
591 struct mbuf *m_getptr(struct mbuf *, int, int *);
592 u_int m_length(struct mbuf *, struct mbuf **);
593 void m_move_pkthdr(struct mbuf *, struct mbuf *);
594 struct mbuf *m_prepend(struct mbuf *, int, int);
595 void m_print(const struct mbuf *, int);
596 struct mbuf *m_pulldown(struct mbuf *, int, int, int *);
597 struct mbuf *m_pullup(struct mbuf *, int);
598 int m_sanity(struct mbuf *, int);
599 struct mbuf *m_split(struct mbuf *, int, int);
600 struct mbuf *m_uiotombuf(struct uio *, int, int, int);
603 * Network packets may have annotations attached by affixing a list
604 * of "packet tags" to the pkthdr structure. Packet tags are
605 * dynamically allocated semi-opaque data structures that have
606 * a fixed header (struct m_tag) that specifies the size of the
607 * memory block and a <cookie,type> pair that identifies it.
608 * The cookie is a 32-bit unique unsigned value used to identify
609 * a module or ABI. By convention this value is chose as the
610 * date+time that the module is created, expressed as the number of
611 * seconds since the epoch (e.g., using date -u +'%s'). The type value
612 * is an ABI/module-specific value that identifies a particular annotation
613 * and is private to the module. For compatibility with systems
614 * like OpenBSD that define packet tags w/o an ABI/module cookie,
615 * the value PACKET_ABI_COMPAT is used to implement m_tag_get and
616 * m_tag_find compatibility shim functions and several tag types are
617 * defined below. Users that do not require compatibility should use
618 * a private cookie value so that packet tag-related definitions
619 * can be maintained privately.
621 * Note that the packet tag returned by m_tag_alloc has the default
622 * memory alignment implemented by malloc. To reference private data
623 * one can use a construct like:
625 * struct m_tag *mtag = m_tag_alloc(...);
626 * struct foo *p = (struct foo *)(mtag+1);
628 * if the alignment of struct m_tag is sufficient for referencing members
629 * of struct foo. Otherwise it is necessary to embed struct m_tag within
630 * the private data structure to insure proper alignment; e.g.,
636 * struct foo *p = (struct foo *) m_tag_alloc(...);
637 * struct m_tag *mtag = &p->tag;
641 * Persistent tags stay with an mbuf until the mbuf is reclaimed.
642 * Otherwise tags are expected to ``vanish'' when they pass through
643 * a network interface. For most interfaces this happens normally
644 * as the tags are reclaimed when the mbuf is free'd. However in
645 * some special cases reclaiming must be done manually. An example
646 * is packets that pass through the loopback interface. Also, one
647 * must be careful to do this when ``turning around'' packets (e.g.,
650 * To mark a tag persistent bit-or this flag in when defining the
651 * tag id. The tag will then be treated as described above.
653 #define MTAG_PERSISTENT 0x800
655 #define PACKET_TAG_NONE 0 /* Nadda */
657 /* Packet tags for use with PACKET_ABI_COMPAT. */
658 #define PACKET_TAG_IPSEC_IN_DONE 1 /* IPsec applied, in */
659 #define PACKET_TAG_IPSEC_OUT_DONE 2 /* IPsec applied, out */
660 #define PACKET_TAG_IPSEC_IN_CRYPTO_DONE 3 /* NIC IPsec crypto done */
661 #define PACKET_TAG_IPSEC_OUT_CRYPTO_NEEDED 4 /* NIC IPsec crypto req'ed */
662 #define PACKET_TAG_IPSEC_IN_COULD_DO_CRYPTO 5 /* NIC notifies IPsec */
663 #define PACKET_TAG_IPSEC_PENDING_TDB 6 /* Reminder to do IPsec */
664 #define PACKET_TAG_BRIDGE 7 /* Bridge processing done */
665 #define PACKET_TAG_GIF 8 /* GIF processing done */
666 #define PACKET_TAG_GRE 9 /* GRE processing done */
667 #define PACKET_TAG_IN_PACKET_CHECKSUM 10 /* NIC checksumming done */
668 #define PACKET_TAG_ENCAP 11 /* Encap. processing */
669 #define PACKET_TAG_IPSEC_SOCKET 12 /* IPSEC socket ref */
670 #define PACKET_TAG_IPSEC_HISTORY 13 /* IPSEC history */
671 #define PACKET_TAG_IPV6_INPUT 14 /* IPV6 input processing */
672 #define PACKET_TAG_DUMMYNET 15 /* dummynet info */
673 #define PACKET_TAG_DIVERT 17 /* divert info */
674 #define PACKET_TAG_IPFORWARD 18 /* ipforward info */
675 #define PACKET_TAG_MACLABEL (19 | MTAG_PERSISTENT) /* MAC label */
676 #define PACKET_TAG_PF_ROUTED 21 /* PF routed, avoid loops */
677 #define PACKET_TAG_PF_FRAGCACHE 22 /* PF fragment cached */
678 #define PACKET_TAG_PF_QID 23 /* PF ALTQ queue id */
679 #define PACKET_TAG_PF_TAG 24 /* PF tagged */
680 #define PACKET_TAG_RTSOCKFAM 25 /* rtsock sa family */
681 #define PACKET_TAG_PF_TRANSLATE_LOCALHOST 26 /* PF translate localhost */
682 #define PACKET_TAG_IPOPTIONS 27 /* Saved IP options */
683 #define PACKET_TAG_CARP 28 /* CARP info */
685 /* Packet tag routines. */
686 struct m_tag *m_tag_alloc(u_int32_t, int, int, int);
687 void m_tag_delete(struct mbuf *, struct m_tag *);
688 void m_tag_delete_chain(struct mbuf *, struct m_tag *);
689 void m_tag_free_default(struct m_tag *);
690 struct m_tag *m_tag_locate(struct mbuf *, u_int32_t, int, struct m_tag *);
691 struct m_tag *m_tag_copy(struct m_tag *, int);
692 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int);
693 void m_tag_delete_nonpersistent(struct mbuf *);
696 * Initialize the list of tags associated with an mbuf.
699 m_tag_init(struct mbuf *m)
701 SLIST_INIT(&m->m_pkthdr.tags);
705 * Set up the contents of a tag. Note that this does not
706 * fill in the free method; the caller is expected to do that.
708 * XXX probably should be called m_tag_init, but that was
712 m_tag_setup(struct m_tag *t, u_int32_t cookie, int type, int len)
716 t->m_tag_cookie = cookie;
720 * Reclaim resources associated with a tag.
723 m_tag_free(struct m_tag *t)
729 * Return the first tag associated with an mbuf.
731 static __inline struct m_tag *
732 m_tag_first(struct mbuf *m)
734 return (SLIST_FIRST(&m->m_pkthdr.tags));
738 * Return the next tag in the list of tags associated with an mbuf.
740 static __inline struct m_tag *
741 m_tag_next(struct mbuf *m, struct m_tag *t)
743 return (SLIST_NEXT(t, m_tag_link));
747 * Prepend a tag to the list of tags associated with an mbuf.
750 m_tag_prepend(struct mbuf *m, struct m_tag *t)
752 SLIST_INSERT_HEAD(&m->m_pkthdr.tags, t, m_tag_link);
756 * Unlink a tag from the list of tags associated with an mbuf.
759 m_tag_unlink(struct mbuf *m, struct m_tag *t)
761 SLIST_REMOVE(&m->m_pkthdr.tags, t, m_tag, m_tag_link);
764 /* These are for OpenBSD compatibility. */
765 #define MTAG_ABI_COMPAT 0 /* compatibility ABI */
767 static __inline struct m_tag *
768 m_tag_get(int type, int length, int wait)
770 return (m_tag_alloc(MTAG_ABI_COMPAT, type, length, wait));
773 static __inline struct m_tag *
774 m_tag_find(struct mbuf *m, int type, struct m_tag *start)
776 return (SLIST_EMPTY(&m->m_pkthdr.tags) ?
777 NULL : m_tag_locate(m, MTAG_ABI_COMPAT, type, start));
782 #endif /* !_SYS_MBUF_H_ */