1 /* $OpenBSD: mbuf.h,v 1.263 2024/04/14 20:46:27 bluhm Exp $ */
2 /* $NetBSD: mbuf.h,v 1.19 1996/02/09 18:25:14 christos Exp $ */
3
4 /*
5 * Copyright (c) 1982, 1986, 1988, 1993
6 * The Regents of the University of California. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * @(#)mbuf.h 8.5 (Berkeley) 2/19/95
33 */
34
35 #ifndef _SYS_MBUF_H_
36 #define _SYS_MBUF_H_
37
38 #include <sys/queue.h>
39
40 /*
41 * Constants related to network buffer management.
42 * MCLBYTES must be no larger than PAGE_SIZE (the software page size) and,
43 * on machines that exchange pages of input or output buffers with mbuf
44 * clusters (MAPPED_MBUFS), MCLBYTES must also be an integral multiple
45 * of the hardware page size.
46 */
47 #define MSIZE 256 /* size of an mbuf */
48
49 /*
50 * Mbufs are of a single size, MSIZE, which includes overhead. An mbuf may
51 * add a single "mbuf cluster" of size MCLBYTES, which has no additional
52 * overhead and is used instead of the internal data area; this is done when
53 * at least MINCLSIZE of data must be stored.
54 */
55
56 #define MLEN (MSIZE - sizeof(struct m_hdr)) /* normal data len */
57 #define MHLEN (MLEN - sizeof(struct pkthdr)) /* data len w/pkthdr */
58
59 #define MAXMCLBYTES (64 * 1024) /* largest cluster from the stack */
60 #define MINCLSIZE (MHLEN + MLEN + 1) /* smallest amount to put in cluster */
61 #define M_MAXCOMPRESS (MHLEN / 2) /* max amount to copy for compression */
62
63 #define MCLSHIFT 11 /* convert bytes to m_buf clusters */
64 /* 2K cluster can hold Ether frame */
65 #define MCLBYTES (1 << MCLSHIFT) /* size of a m_buf cluster */
66 #define MCLOFSET (MCLBYTES - 1)
67
68 /* Packet tags structure */
69 struct m_tag {
70 SLIST_ENTRY(m_tag) m_tag_link; /* List of packet tags */
71 u_int16_t m_tag_id; /* Tag ID */
72 u_int16_t m_tag_len; /* Length of data */
73 };
74
75 /*
76 * Macros for type conversion
77 * mtod(m,t) - convert mbuf pointer to data pointer of correct type
78 */
79 #define mtod(m,t) ((t)((m)->m_data))
80
81 /* header at beginning of each mbuf: */
82 struct m_hdr {
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 u_int mh_len; /* amount of data in this mbuf */
87 short mh_type; /* type of data in this mbuf */
88 u_short mh_flags; /* flags; see below */
89 #ifndef __LP64__
90 u_int mh_pad; /* pad to 8-byte boundary */
91 #endif
92 };
93
94 /* pf stuff */
95 struct pf_state_key;
96 struct inpcb;
97
98 struct pkthdr_pf {
99 struct pf_state_key *statekey; /* pf stackside statekey */
100 struct inpcb *inp; /* connected pcb for outgoing packet */
101 u_int32_t qid; /* queue id */
102 u_int16_t tag; /* tag id */
103 u_int16_t delay; /* delay packet by X ms */
104 u_int8_t flags;
105 u_int8_t routed;
106 u_int8_t prio;
107 u_int8_t pad[1];
108 };
109
110 /* pkthdr_pf.flags */
111 #define PF_TAG_GENERATED 0x01
112 #define PF_TAG_SYNCOOKIE_RECREATED 0x02
113 #define PF_TAG_TRANSLATE_LOCALHOST 0x04
114 #define PF_TAG_DIVERTED 0x08
115 #define PF_TAG_DIVERTED_PACKET 0x10
116 #define PF_TAG_REROUTE 0x20
117 #define PF_TAG_REFRAGMENTED 0x40 /* refragmented ipv6 packet */
118 #define PF_TAG_PROCESSED 0x80 /* packet was checked by pf */
119
120 #ifdef _KERNEL
121 #define MPF_BITS \
122 ("\20\1GENERATED\2SYNCOOKIE_RECREATED\3TRANSLATE_LOCALHOST\4DIVERTED" \
123 "\5DIVERTED_PACKET\6REROUTE\7REFRAGMENTED\10PROCESSED")
124 #endif
125
126 /* record/packet header in first mbuf of chain; valid if M_PKTHDR set */
127 struct pkthdr {
128 void *ph_cookie; /* additional data */
129 SLIST_HEAD(, m_tag) ph_tags; /* list of packet tags */
130 int64_t ph_timestamp; /* packet timestamp */
131 int len; /* total packet length */
132 u_int ph_rtableid; /* routing table id */
133 u_int ph_ifidx; /* rcv interface index */
134 u_int16_t ph_tagsset; /* mtags attached */
135 u_int16_t ph_flowid; /* pseudo unique flow id */
136 u_int16_t csum_flags; /* checksum flags */
137 u_int16_t ether_vtag; /* Ethernet 802.1p+Q vlan tag */
138 u_int16_t ph_mss; /* TCP max segment size */
139 u_int8_t ph_loopcnt; /* mbuf is looping in kernel */
140 u_int8_t ph_family; /* af, used when queueing */
141 struct pkthdr_pf pf;
142 };
143
144 /* description of external storage mapped into mbuf, valid if M_EXT set */
145 struct mbuf_ext {
146 caddr_t ext_buf; /* start of buffer */
147 void *ext_arg;
148 u_int ext_free_fn; /* index of free function */
149 u_int ext_size; /* size of buffer, for ext_free_fn */
150 struct mbuf *ext_nextref;
151 struct mbuf *ext_prevref;
152 #ifdef DEBUG
153 const char *ext_ofile;
154 const char *ext_nfile;
155 int ext_oline;
156 int ext_nline;
157 #endif
158 };
159
160 struct mbuf {
161 struct m_hdr m_hdr;
162 union {
163 struct {
164 struct pkthdr MH_pkthdr; /* M_PKTHDR set */
165 union {
166 struct mbuf_ext MH_ext; /* M_EXT set */
167 char MH_databuf[MHLEN];
168 } MH_dat;
169 } MH;
170 char M_databuf[MLEN]; /* !M_PKTHDR, !M_EXT */
171 } M_dat;
172 };
173 #define m_next m_hdr.mh_next
174 #define m_len m_hdr.mh_len
175 #define m_data m_hdr.mh_data
176 #define m_type m_hdr.mh_type
177 #define m_flags m_hdr.mh_flags
178 #define m_nextpkt m_hdr.mh_nextpkt
179 #define m_pkthdr M_dat.MH.MH_pkthdr
180 #define m_ext M_dat.MH.MH_dat.MH_ext
181 #define m_pktdat M_dat.MH.MH_dat.MH_databuf
182 #define m_dat M_dat.M_databuf
183
184 /* mbuf flags */
185 #define M_EXT 0x0001 /* has associated external storage */
186 #define M_PKTHDR 0x0002 /* start of record */
187 #define M_EOR 0x0004 /* end of record */
188 #define M_EXTWR 0x0008 /* external storage is writable */
189 #define M_PROTO1 0x0010 /* protocol-specific */
190
191 /* mbuf pkthdr flags, also in m_flags */
192 #define M_VLANTAG 0x0020 /* ether_vtag is valid */
193 #define M_LOOP 0x0040 /* packet has been sent from local machine */
194 #define M_BCAST 0x0100 /* sent/received as link-level broadcast */
195 #define M_MCAST 0x0200 /* sent/received as link-level multicast */
196 #define M_CONF 0x0400 /* payload was encrypted (ESP-transport) */
197 #define M_AUTH 0x0800 /* payload was authenticated (AH or ESP auth) */
198 #define M_TUNNEL 0x1000 /* IP-in-IP added by tunnel mode IPsec */
199 #define M_ZEROIZE 0x2000 /* Zeroize data part on free */
200 #define M_COMP 0x4000 /* header was decompressed */
201 #define M_LINK0 0x8000 /* link layer specific flag */
202
203 #ifdef _KERNEL
204 #define M_BITS \
205 ("\20\1M_EXT\2M_PKTHDR\3M_EOR\4M_EXTWR\5M_PROTO1\6M_VLANTAG\7M_LOOP" \
206 "\11M_BCAST\12M_MCAST\13M_CONF\14M_AUTH\15M_TUNNEL" \
207 "\16M_ZEROIZE\17M_COMP\20M_LINK0")
208 #endif
209
210 /* flags copied when copying m_pkthdr */
211 #define M_COPYFLAGS (M_PKTHDR|M_EOR|M_PROTO1|M_BCAST|M_MCAST|M_CONF|M_COMP|\
212 M_AUTH|M_LOOP|M_TUNNEL|M_LINK0|M_VLANTAG|M_ZEROIZE)
213
214 /* Checksumming flags */
215 #define M_IPV4_CSUM_OUT 0x0001 /* IPv4 checksum needed */
216 #define M_TCP_CSUM_OUT 0x0002 /* TCP checksum needed */
217 #define M_UDP_CSUM_OUT 0x0004 /* UDP checksum needed */
218 #define M_IPV4_CSUM_IN_OK 0x0008 /* IPv4 checksum verified */
219 #define M_IPV4_CSUM_IN_BAD 0x0010 /* IPv4 checksum bad */
220 #define M_TCP_CSUM_IN_OK 0x0020 /* TCP checksum verified */
221 #define M_TCP_CSUM_IN_BAD 0x0040 /* TCP checksum bad */
222 #define M_UDP_CSUM_IN_OK 0x0080 /* UDP checksum verified */
223 #define M_UDP_CSUM_IN_BAD 0x0100 /* UDP checksum bad */
224 #define M_ICMP_CSUM_OUT 0x0200 /* ICMP/ICMPv6 checksum needed */
225 #define M_ICMP_CSUM_IN_OK 0x0400 /* ICMP/ICMPv6 checksum verified */
226 #define M_ICMP_CSUM_IN_BAD 0x0800 /* ICMP/ICMPv6 checksum bad */
227 #define M_IPV6_DF_OUT 0x1000 /* don't fragment outgoing IPv6 */
228 #define M_TIMESTAMP 0x2000 /* ph_timestamp is set */
229 #define M_FLOWID 0x4000 /* ph_flowid is set */
230 #define M_TCP_TSO 0x8000 /* TCP Segmentation Offload needed */
231
232 #ifdef _KERNEL
233 #define MCS_BITS \
234 ("\20\1IPV4_CSUM_OUT\2TCP_CSUM_OUT\3UDP_CSUM_OUT\4IPV4_CSUM_IN_OK" \
235 "\5IPV4_CSUM_IN_BAD\6TCP_CSUM_IN_OK\7TCP_CSUM_IN_BAD\10UDP_CSUM_IN_OK" \
236 "\11UDP_CSUM_IN_BAD\12ICMP_CSUM_OUT\13ICMP_CSUM_IN_OK\14ICMP_CSUM_IN_BAD" \
237 "\15IPV6_NODF_OUT" "\16TIMESTAMP" "\17FLOWID" "\20TCP_TSO")
238 #endif
239
240 /* mbuf types */
241 #define MT_FREE 0 /* should be on free list */
242 #define MT_DATA 1 /* dynamic (data) allocation */
243 #define MT_HEADER 2 /* packet header */
244 #define MT_SONAME 3 /* socket name */
245 #define MT_SOOPTS 4 /* socket options */
246 #define MT_FTABLE 5 /* fragment reassembly header */
247 #define MT_CONTROL 6 /* extra-data protocol message */
248 #define MT_OOBDATA 7 /* expedited data */
249 #define MT_NTYPES 8
250
251 /* flags to m_get/MGET */
252 #include <sys/malloc.h>
253 #define M_DONTWAIT M_NOWAIT
254 #define M_WAIT M_WAITOK
255
256 /*
257 * mbuf allocation/deallocation macros:
258 *
259 * MGET(struct mbuf *m, int how, int type)
260 * allocates an mbuf and initializes it to contain internal data.
261 *
262 * MGETHDR(struct mbuf *m, int how, int type)
263 * allocates an mbuf and initializes it to contain a packet header
264 * and internal data.
265 */
266 #define MGET(m, how, type) m = m_get((how), (type))
267
268 #define MGETHDR(m, how, type) m = m_gethdr((how), (type))
269
270 /*
271 * Macros for tracking external storage associated with an mbuf.
272 */
273 #ifdef DEBUG
274 #define MCLREFDEBUGN(m, file, line) do { \
275 (m)->m_ext.ext_nfile = (file); \
276 (m)->m_ext.ext_nline = (line); \
277 } while (/* CONSTCOND */ 0)
278 #define MCLREFDEBUGO(m, file, line) do { \
279 (m)->m_ext.ext_ofile = (file); \
280 (m)->m_ext.ext_oline = (line); \
281 } while (/* CONSTCOND */ 0)
282 #else
283 #define MCLREFDEBUGN(m, file, line)
284 #define MCLREFDEBUGO(m, file, line)
285 #endif
286
287 #define MCLISREFERENCED(m) ((m)->m_ext.ext_nextref != (m))
288
289 #define MCLADDREFERENCE(o, n) m_extref((o), (n))
290
291 #define MCLINITREFERENCE(m) do { \
292 (m)->m_ext.ext_prevref = (m); \
293 (m)->m_ext.ext_nextref = (m); \
294 MCLREFDEBUGO((m), __FILE__, __LINE__); \
295 MCLREFDEBUGN((m), NULL, 0); \
296 } while (/* CONSTCOND */ 0)
297
298 /*
299 * Macros for mbuf external storage.
300 *
301 * MEXTADD adds pre-allocated external storage to
302 * a normal mbuf; the flag M_EXT is set.
303 *
304 * MCLGET allocates and adds an mbuf cluster to a normal mbuf;
305 * the flag M_EXT is set upon success.
306 */
307 #define MEXTADD(m, buf, size, mflags, freefn, arg) do { \
308 (m)->m_data = (m)->m_ext.ext_buf = (caddr_t)(buf); \
309 (m)->m_flags |= M_EXT | (mflags & M_EXTWR); \
310 (m)->m_ext.ext_size = (size); \
311 (m)->m_ext.ext_free_fn = (freefn); \
312 (m)->m_ext.ext_arg = (arg); \
313 MCLINITREFERENCE(m); \
314 } while (/* CONSTCOND */ 0)
315
316 #define MCLGET(m, how) (void) m_clget((m), (how), MCLBYTES)
317 #define MCLGETL(m, how, l) m_clget((m), (how), (l))
318
319 u_int mextfree_register(void (*)(caddr_t, u_int, void *));
320 #define MEXTFREE_POOL 0
321
322 /*
323 * Move just m_pkthdr from from to to,
324 * remove M_PKTHDR and clean flags/tags for from.
325 */
326 #define M_MOVE_HDR(to, from) do { \
327 (to)->m_pkthdr = (from)->m_pkthdr; \
328 (from)->m_flags &= ~M_PKTHDR; \
329 SLIST_INIT(&(from)->m_pkthdr.ph_tags); \
330 (from)->m_pkthdr.pf.statekey = NULL; \
331 } while (/* CONSTCOND */ 0)
332
333 /*
334 * MOVE mbuf pkthdr from from to to.
335 * from must have M_PKTHDR set, and to must be empty.
336 */
337 #define M_MOVE_PKTHDR(to, from) do { \
338 (to)->m_flags = ((to)->m_flags & (M_EXT | M_EXTWR)); \
339 (to)->m_flags |= (from)->m_flags & M_COPYFLAGS; \
340 M_MOVE_HDR((to), (from)); \
341 if (((to)->m_flags & M_EXT) == 0) \
342 (to)->m_data = (to)->m_pktdat; \
343 } while (/* CONSTCOND */ 0)
344
345 /*
346 * Determine if an mbuf's data area is read-only. This is true for
347 * non-cluster external storage and for clusters that are being
348 * referenced by more than one mbuf.
349 */
350 #define M_READONLY(m) \
351 (((m)->m_flags & M_EXT) != 0 && \
352 (((m)->m_flags & M_EXTWR) == 0 || MCLISREFERENCED(m)))
353
354 /*
355 * Arrange to prepend space of size plen to mbuf m.
356 * If a new mbuf must be allocated, how specifies whether to wait.
357 * If how is M_DONTWAIT and allocation fails, the original mbuf chain
358 * is freed and m is set to NULL.
359 */
360 #define M_PREPEND(m, plen, how) \
361 (m) = m_prepend((m), (plen), (how))
362
363 /* length to m_copy to copy all */
364 #define M_COPYALL 1000000000
365
366 #define MBSTAT_TYPES MT_NTYPES
367 #define MBSTAT_DROPS (MBSTAT_TYPES + 0)
368 #define MBSTAT_WAIT (MBSTAT_TYPES + 1)
369 #define MBSTAT_DRAIN (MBSTAT_TYPES + 2)
370 #define MBSTAT_COUNT (MBSTAT_TYPES + 3)
371
372 /*
373 * Mbuf statistics.
374 * For statistics related to mbuf and cluster allocations, see also the
375 * pool headers (mbpool and mclpool).
376 */
377 struct mbstat {
378 u_long m_drops; /* times failed to find space */
379 u_long m_wait; /* times waited for space */
380 u_long m_drain; /* times drained protocols for space */
381 u_long m_mtypes[MBSTAT_COUNT];
382 /* type specific mbuf allocations */
383 };
384
385 #include <sys/mutex.h>
386
387 struct mbuf_list {
388 struct mbuf *ml_head;
389 struct mbuf *ml_tail;
390 u_int ml_len;
391 };
392
393 struct mbuf_queue {
394 struct mutex mq_mtx;
395 struct mbuf_list mq_list;
396 u_int mq_maxlen;
397 u_int mq_drops;
398 };
399
400 #ifdef _KERNEL
401 struct pool;
402
403 extern long nmbclust; /* limit on the # of clusters */
404 extern int max_linkhdr; /* largest link-level header */
405 extern int max_protohdr; /* largest protocol header */
406 extern int max_hdr; /* largest link+protocol header */
407
408 void mbinit(void);
409 void mbcpuinit(void);
410 int nmbclust_update(long);
411 struct mbuf *m_copym(struct mbuf *, int, int, int);
412 struct mbuf *m_free(struct mbuf *);
413 struct mbuf *m_get(int, int);
414 struct mbuf *m_getclr(int, int);
415 struct mbuf *m_gethdr(int, int);
416 struct mbuf *m_inithdr(struct mbuf *);
417 void m_removehdr(struct mbuf *);
418 void m_resethdr(struct mbuf *);
419 void m_calchdrlen(struct mbuf *);
420 int m_defrag(struct mbuf *, int);
421 struct mbuf *m_prepend(struct mbuf *, int, int);
422 struct mbuf *m_pulldown(struct mbuf *, int, int, int *);
423 struct mbuf *m_pullup(struct mbuf *, int);
424 struct mbuf *m_split(struct mbuf *, int, int);
425 struct mbuf *m_makespace(struct mbuf *, int, int, int *);
426 struct mbuf *m_getptr(struct mbuf *, int, int *);
427 int m_leadingspace(struct mbuf *);
428 int m_trailingspace(struct mbuf *);
429 void m_align(struct mbuf *, int);
430 struct mbuf *m_clget(struct mbuf *, int, u_int);
431 void m_extref(struct mbuf *, struct mbuf *);
432 void m_pool_init(struct pool *, u_int, u_int, const char *);
433 u_int m_pool_used(void);
434 void m_extfree_pool(caddr_t, u_int, void *);
435 void m_adj(struct mbuf *, int);
436 int m_copyback(struct mbuf *, int, int, const void *, int);
437 struct mbuf *m_freem(struct mbuf *);
438 void m_purge(struct mbuf *);
439 void m_copydata(struct mbuf *, int, int, void *);
440 void m_cat(struct mbuf *, struct mbuf *);
441 struct mbuf *m_devget(char *, int, int);
442 int m_apply(struct mbuf *, int, int,
443 int (*)(caddr_t, caddr_t, unsigned int), caddr_t);
444 struct mbuf *m_dup_pkt(struct mbuf *, unsigned int, int);
445 int m_dup_pkthdr(struct mbuf *, struct mbuf *, int);
446
447 void m_microtime(const struct mbuf *, struct timeval *);
448
449 static inline struct mbuf *
m_freemp(struct mbuf ** mp)450 m_freemp(struct mbuf **mp)
451 {
452 struct mbuf *m = *mp;
453
454 *mp = NULL;
455 return m_freem(m);
456 }
457
458 /* Packet tag routines */
459 struct m_tag *m_tag_get(int, int, int);
460 void m_tag_prepend(struct mbuf *, struct m_tag *);
461 void m_tag_delete(struct mbuf *, struct m_tag *);
462 void m_tag_delete_chain(struct mbuf *);
463 struct m_tag *m_tag_find(struct mbuf *, int, struct m_tag *);
464 struct m_tag *m_tag_copy(struct m_tag *, int);
465 int m_tag_copy_chain(struct mbuf *, struct mbuf *, int);
466 void m_tag_init(struct mbuf *);
467 struct m_tag *m_tag_first(struct mbuf *);
468 struct m_tag *m_tag_next(struct mbuf *, struct m_tag *);
469
470 /* Packet tag types */
471 #define PACKET_TAG_IPSEC_IN_DONE 0x0001 /* IPsec applied, in */
472 #define PACKET_TAG_IPSEC_OUT_DONE 0x0002 /* IPsec applied, out */
473 #define PACKET_TAG_IPSEC_FLOWINFO 0x0004 /* IPsec flowinfo */
474 #define PACKET_TAG_IP_OFFNXT 0x0010 /* IPv4 offset and next proto */
475 #define PACKET_TAG_IP6_OFFNXT 0x0020 /* IPv6 offset and next proto */
476 #define PACKET_TAG_WIREGUARD 0x0040 /* WireGuard data */
477 #define PACKET_TAG_GRE 0x0080 /* GRE processing done */
478 #define PACKET_TAG_DLT 0x0100 /* data link layer type */
479 #define PACKET_TAG_PF_DIVERT 0x0200 /* pf(4) diverted packet */
480 #define PACKET_TAG_PF_REASSEMBLED 0x0800 /* pf reassembled ipv6 packet */
481 #define PACKET_TAG_SRCROUTE 0x1000 /* IPv4 source routing options */
482 #define PACKET_TAG_TUNNEL 0x2000 /* Tunnel endpoint address */
483 #define PACKET_TAG_CARP_BAL_IP 0x4000 /* carp(4) ip balanced marker */
484
485 #define MTAG_BITS \
486 ("\20\1IPSEC_IN_DONE\2IPSEC_OUT_DONE\3IPSEC_FLOWINFO" \
487 "\4IPSEC_OUT_CRYPTO_NEEDED\5IPSEC_PENDING_TDB\6BRIDGE\7WG\10GRE\11DLT" \
488 "\12PF_DIVERT\14PF_REASSEMBLED\15SRCROUTE\16TUNNEL\17CARP_BAL_IP")
489
490 /*
491 * Maximum tag payload length (that is excluding the m_tag structure).
492 * Please make sure to update this value when increasing the payload
493 * length for an existing packet tag type or when adding a new one that
494 * has payload larger than the value below.
495 */
496 #define PACKET_TAG_MAXSIZE 80
497
498 /* Detect mbufs looping in the kernel when spliced too often. */
499 #define M_MAXLOOP 128
500
501 /*
502 * mbuf lists
503 */
504
505 #define MBUF_LIST_INITIALIZER() { NULL, NULL, 0 }
506
507 void ml_init(struct mbuf_list *);
508 void ml_enqueue(struct mbuf_list *, struct mbuf *);
509 struct mbuf * ml_dequeue(struct mbuf_list *);
510 void ml_enlist(struct mbuf_list *, struct mbuf_list *);
511 struct mbuf * ml_dechain(struct mbuf_list *);
512 unsigned int ml_purge(struct mbuf_list *);
513 unsigned int ml_hdatalen(struct mbuf_list *);
514
515 #define ml_len(_ml) ((_ml)->ml_len)
516 #define ml_empty(_ml) ((_ml)->ml_len == 0)
517
518 #define MBUF_LIST_FIRST(_ml) ((_ml)->ml_head)
519 #define MBUF_LIST_NEXT(_m) ((_m)->m_nextpkt)
520
521 #define MBUF_LIST_FOREACH(_ml, _m) \
522 for ((_m) = MBUF_LIST_FIRST(_ml); \
523 (_m) != NULL; \
524 (_m) = MBUF_LIST_NEXT(_m))
525
526 /*
527 * mbuf queues
528 */
529
530 #include <sys/atomic.h>
531
532 #define MBUF_QUEUE_INITIALIZER(_maxlen, _ipl) \
533 { MUTEX_INITIALIZER(_ipl), MBUF_LIST_INITIALIZER(), (_maxlen), 0 }
534
535 void mq_init(struct mbuf_queue *, u_int, int);
536 int mq_push(struct mbuf_queue *, struct mbuf *);
537 int mq_enqueue(struct mbuf_queue *, struct mbuf *);
538 struct mbuf * mq_dequeue(struct mbuf_queue *);
539 int mq_enlist(struct mbuf_queue *, struct mbuf_list *);
540 void mq_delist(struct mbuf_queue *, struct mbuf_list *);
541 struct mbuf * mq_dechain(struct mbuf_queue *);
542 unsigned int mq_purge(struct mbuf_queue *);
543 unsigned int mq_hdatalen(struct mbuf_queue *);
544 void mq_set_maxlen(struct mbuf_queue *, u_int);
545
546 #define mq_len(_mq) READ_ONCE((_mq)->mq_list.ml_len)
547 #define mq_empty(_mq) (mq_len(_mq) == 0)
548 #define mq_full(_mq) (mq_len((_mq)) >= READ_ONCE((_mq)->mq_maxlen))
549 #define mq_drops(_mq) READ_ONCE((_mq)->mq_drops)
550
551 #endif /* _KERNEL */
552 #endif /* _SYS_MBUF_H_ */
553